SemaDecl.cpp revision 73d7115d5bb3aa845ac04fe61f3a94491b24cba3
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "clang/AST/APValue.h" 21#include "clang/AST/ASTConsumer.h" 22#include "clang/AST/ASTContext.h" 23#include "clang/AST/CXXInheritance.h" 24#include "clang/AST/DeclCXX.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/DeclTemplate.h" 27#include "clang/AST/ExprCXX.h" 28#include "clang/AST/StmtCXX.h" 29#include "clang/Sema/DeclSpec.h" 30#include "clang/Sema/ParsedTemplate.h" 31#include "clang/Parse/ParseDiagnostic.h" 32#include "clang/Basic/PartialDiagnostic.h" 33#include "clang/Basic/SourceManager.h" 34#include "clang/Basic/TargetInfo.h" 35// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 36#include "clang/Lex/Preprocessor.h" 37#include "clang/Lex/HeaderSearch.h" 38#include "llvm/ADT/Triple.h" 39#include <algorithm> 40#include <cstring> 41#include <functional> 42using namespace clang; 43using namespace sema; 44 45Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 46 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 47} 48 49/// \brief If the identifier refers to a type name within this scope, 50/// return the declaration of that type. 51/// 52/// This routine performs ordinary name lookup of the identifier II 53/// within the given scope, with optional C++ scope specifier SS, to 54/// determine whether the name refers to a type. If so, returns an 55/// opaque pointer (actually a QualType) corresponding to that 56/// type. Otherwise, returns NULL. 57/// 58/// If name lookup results in an ambiguity, this routine will complain 59/// and then return NULL. 60ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 61 Scope *S, CXXScopeSpec *SS, 62 bool isClassName, 63 ParsedType ObjectTypePtr) { 64 // Determine where we will perform name lookup. 65 DeclContext *LookupCtx = 0; 66 if (ObjectTypePtr) { 67 QualType ObjectType = ObjectTypePtr.get(); 68 if (ObjectType->isRecordType()) 69 LookupCtx = computeDeclContext(ObjectType); 70 } else if (SS && SS->isNotEmpty()) { 71 LookupCtx = computeDeclContext(*SS, false); 72 73 if (!LookupCtx) { 74 if (isDependentScopeSpecifier(*SS)) { 75 // C++ [temp.res]p3: 76 // A qualified-id that refers to a type and in which the 77 // nested-name-specifier depends on a template-parameter (14.6.2) 78 // shall be prefixed by the keyword typename to indicate that the 79 // qualified-id denotes a type, forming an 80 // elaborated-type-specifier (7.1.5.3). 81 // 82 // We therefore do not perform any name lookup if the result would 83 // refer to a member of an unknown specialization. 84 if (!isClassName) 85 return ParsedType(); 86 87 // We know from the grammar that this name refers to a type, 88 // so build a dependent node to describe the type. 89 QualType T = 90 CheckTypenameType(ETK_None, SS->getScopeRep(), II, 91 SourceLocation(), SS->getRange(), NameLoc); 92 return ParsedType::make(T); 93 } 94 95 return ParsedType(); 96 } 97 98 if (!LookupCtx->isDependentContext() && 99 RequireCompleteDeclContext(*SS, LookupCtx)) 100 return ParsedType(); 101 } 102 103 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 104 // lookup for class-names. 105 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 106 LookupOrdinaryName; 107 LookupResult Result(*this, &II, NameLoc, Kind); 108 if (LookupCtx) { 109 // Perform "qualified" name lookup into the declaration context we 110 // computed, which is either the type of the base of a member access 111 // expression or the declaration context associated with a prior 112 // nested-name-specifier. 113 LookupQualifiedName(Result, LookupCtx); 114 115 if (ObjectTypePtr && Result.empty()) { 116 // C++ [basic.lookup.classref]p3: 117 // If the unqualified-id is ~type-name, the type-name is looked up 118 // in the context of the entire postfix-expression. If the type T of 119 // the object expression is of a class type C, the type-name is also 120 // looked up in the scope of class C. At least one of the lookups shall 121 // find a name that refers to (possibly cv-qualified) T. 122 LookupName(Result, S); 123 } 124 } else { 125 // Perform unqualified name lookup. 126 LookupName(Result, S); 127 } 128 129 NamedDecl *IIDecl = 0; 130 switch (Result.getResultKind()) { 131 case LookupResult::NotFound: 132 case LookupResult::NotFoundInCurrentInstantiation: 133 case LookupResult::FoundOverloaded: 134 case LookupResult::FoundUnresolvedValue: 135 Result.suppressDiagnostics(); 136 return ParsedType(); 137 138 case LookupResult::Ambiguous: 139 // Recover from type-hiding ambiguities by hiding the type. We'll 140 // do the lookup again when looking for an object, and we can 141 // diagnose the error then. If we don't do this, then the error 142 // about hiding the type will be immediately followed by an error 143 // that only makes sense if the identifier was treated like a type. 144 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 145 Result.suppressDiagnostics(); 146 return ParsedType(); 147 } 148 149 // Look to see if we have a type anywhere in the list of results. 150 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 151 Res != ResEnd; ++Res) { 152 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 153 if (!IIDecl || 154 (*Res)->getLocation().getRawEncoding() < 155 IIDecl->getLocation().getRawEncoding()) 156 IIDecl = *Res; 157 } 158 } 159 160 if (!IIDecl) { 161 // None of the entities we found is a type, so there is no way 162 // to even assume that the result is a type. In this case, don't 163 // complain about the ambiguity. The parser will either try to 164 // perform this lookup again (e.g., as an object name), which 165 // will produce the ambiguity, or will complain that it expected 166 // a type name. 167 Result.suppressDiagnostics(); 168 return ParsedType(); 169 } 170 171 // We found a type within the ambiguous lookup; diagnose the 172 // ambiguity and then return that type. This might be the right 173 // answer, or it might not be, but it suppresses any attempt to 174 // perform the name lookup again. 175 break; 176 177 case LookupResult::Found: 178 IIDecl = Result.getFoundDecl(); 179 break; 180 } 181 182 assert(IIDecl && "Didn't find decl"); 183 184 QualType T; 185 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 186 DiagnoseUseOfDecl(IIDecl, NameLoc); 187 188 if (T.isNull()) 189 T = Context.getTypeDeclType(TD); 190 191 if (SS) 192 T = getElaboratedType(ETK_None, *SS, T); 193 194 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 195 T = Context.getObjCInterfaceType(IDecl); 196 } else { 197 // If it's not plausibly a type, suppress diagnostics. 198 Result.suppressDiagnostics(); 199 return ParsedType(); 200 } 201 202 return ParsedType::make(T); 203} 204 205/// isTagName() - This method is called *for error recovery purposes only* 206/// to determine if the specified name is a valid tag name ("struct foo"). If 207/// so, this returns the TST for the tag corresponding to it (TST_enum, 208/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 209/// where the user forgot to specify the tag. 210DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 211 // Do a tag name lookup in this scope. 212 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 213 LookupName(R, S, false); 214 R.suppressDiagnostics(); 215 if (R.getResultKind() == LookupResult::Found) 216 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 217 switch (TD->getTagKind()) { 218 default: return DeclSpec::TST_unspecified; 219 case TTK_Struct: return DeclSpec::TST_struct; 220 case TTK_Union: return DeclSpec::TST_union; 221 case TTK_Class: return DeclSpec::TST_class; 222 case TTK_Enum: return DeclSpec::TST_enum; 223 } 224 } 225 226 return DeclSpec::TST_unspecified; 227} 228 229bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 230 SourceLocation IILoc, 231 Scope *S, 232 CXXScopeSpec *SS, 233 ParsedType &SuggestedType) { 234 // We don't have anything to suggest (yet). 235 SuggestedType = ParsedType(); 236 237 // There may have been a typo in the name of the type. Look up typo 238 // results, in case we have something that we can suggest. 239 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 240 NotForRedeclaration); 241 242 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 243 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 244 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 245 !Result->isInvalidDecl()) { 246 // We found a similarly-named type or interface; suggest that. 247 if (!SS || !SS->isSet()) 248 Diag(IILoc, diag::err_unknown_typename_suggest) 249 << &II << Lookup.getLookupName() 250 << FixItHint::CreateReplacement(SourceRange(IILoc), 251 Result->getNameAsString()); 252 else if (DeclContext *DC = computeDeclContext(*SS, false)) 253 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 254 << &II << DC << Lookup.getLookupName() << SS->getRange() 255 << FixItHint::CreateReplacement(SourceRange(IILoc), 256 Result->getNameAsString()); 257 else 258 llvm_unreachable("could not have corrected a typo here"); 259 260 Diag(Result->getLocation(), diag::note_previous_decl) 261 << Result->getDeclName(); 262 263 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 264 return true; 265 } 266 } else if (Lookup.empty()) { 267 // We corrected to a keyword. 268 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 269 Diag(IILoc, diag::err_unknown_typename_suggest) 270 << &II << Corrected; 271 return true; 272 } 273 } 274 275 if (getLangOptions().CPlusPlus) { 276 // See if II is a class template that the user forgot to pass arguments to. 277 UnqualifiedId Name; 278 Name.setIdentifier(&II, IILoc); 279 CXXScopeSpec EmptySS; 280 TemplateTy TemplateResult; 281 bool MemberOfUnknownSpecialization; 282 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 283 Name, ParsedType(), true, TemplateResult, 284 MemberOfUnknownSpecialization) == TNK_Type_template) { 285 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 286 Diag(IILoc, diag::err_template_missing_args) << TplName; 287 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 288 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 289 << TplDecl->getTemplateParameters()->getSourceRange(); 290 } 291 return true; 292 } 293 } 294 295 // FIXME: Should we move the logic that tries to recover from a missing tag 296 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 297 298 if (!SS || (!SS->isSet() && !SS->isInvalid())) 299 Diag(IILoc, diag::err_unknown_typename) << &II; 300 else if (DeclContext *DC = computeDeclContext(*SS, false)) 301 Diag(IILoc, diag::err_typename_nested_not_found) 302 << &II << DC << SS->getRange(); 303 else if (isDependentScopeSpecifier(*SS)) { 304 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 305 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 306 << SourceRange(SS->getRange().getBegin(), IILoc) 307 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 308 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 309 } else { 310 assert(SS && SS->isInvalid() && 311 "Invalid scope specifier has already been diagnosed"); 312 } 313 314 return true; 315} 316 317// Determines the context to return to after temporarily entering a 318// context. This depends in an unnecessarily complicated way on the 319// exact ordering of callbacks from the parser. 320DeclContext *Sema::getContainingDC(DeclContext *DC) { 321 322 // Functions defined inline within classes aren't parsed until we've 323 // finished parsing the top-level class, so the top-level class is 324 // the context we'll need to return to. 325 if (isa<FunctionDecl>(DC)) { 326 DC = DC->getLexicalParent(); 327 328 // A function not defined within a class will always return to its 329 // lexical context. 330 if (!isa<CXXRecordDecl>(DC)) 331 return DC; 332 333 // A C++ inline method/friend is parsed *after* the topmost class 334 // it was declared in is fully parsed ("complete"); the topmost 335 // class is the context we need to return to. 336 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 337 DC = RD; 338 339 // Return the declaration context of the topmost class the inline method is 340 // declared in. 341 return DC; 342 } 343 344 // ObjCMethodDecls are parsed (for some reason) outside the context 345 // of the class. 346 if (isa<ObjCMethodDecl>(DC)) 347 return DC->getLexicalParent()->getLexicalParent(); 348 349 return DC->getLexicalParent(); 350} 351 352void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 353 assert(getContainingDC(DC) == CurContext && 354 "The next DeclContext should be lexically contained in the current one."); 355 CurContext = DC; 356 S->setEntity(DC); 357} 358 359void Sema::PopDeclContext() { 360 assert(CurContext && "DeclContext imbalance!"); 361 362 CurContext = getContainingDC(CurContext); 363 assert(CurContext && "Popped translation unit!"); 364} 365 366/// EnterDeclaratorContext - Used when we must lookup names in the context 367/// of a declarator's nested name specifier. 368/// 369void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 370 // C++0x [basic.lookup.unqual]p13: 371 // A name used in the definition of a static data member of class 372 // X (after the qualified-id of the static member) is looked up as 373 // if the name was used in a member function of X. 374 // C++0x [basic.lookup.unqual]p14: 375 // If a variable member of a namespace is defined outside of the 376 // scope of its namespace then any name used in the definition of 377 // the variable member (after the declarator-id) is looked up as 378 // if the definition of the variable member occurred in its 379 // namespace. 380 // Both of these imply that we should push a scope whose context 381 // is the semantic context of the declaration. We can't use 382 // PushDeclContext here because that context is not necessarily 383 // lexically contained in the current context. Fortunately, 384 // the containing scope should have the appropriate information. 385 386 assert(!S->getEntity() && "scope already has entity"); 387 388#ifndef NDEBUG 389 Scope *Ancestor = S->getParent(); 390 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 391 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 392#endif 393 394 CurContext = DC; 395 S->setEntity(DC); 396} 397 398void Sema::ExitDeclaratorContext(Scope *S) { 399 assert(S->getEntity() == CurContext && "Context imbalance!"); 400 401 // Switch back to the lexical context. The safety of this is 402 // enforced by an assert in EnterDeclaratorContext. 403 Scope *Ancestor = S->getParent(); 404 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 405 CurContext = (DeclContext*) Ancestor->getEntity(); 406 407 // We don't need to do anything with the scope, which is going to 408 // disappear. 409} 410 411/// \brief Determine whether we allow overloading of the function 412/// PrevDecl with another declaration. 413/// 414/// This routine determines whether overloading is possible, not 415/// whether some new function is actually an overload. It will return 416/// true in C++ (where we can always provide overloads) or, as an 417/// extension, in C when the previous function is already an 418/// overloaded function declaration or has the "overloadable" 419/// attribute. 420static bool AllowOverloadingOfFunction(LookupResult &Previous, 421 ASTContext &Context) { 422 if (Context.getLangOptions().CPlusPlus) 423 return true; 424 425 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 426 return true; 427 428 return (Previous.getResultKind() == LookupResult::Found 429 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 430} 431 432/// Add this decl to the scope shadowed decl chains. 433void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 434 // Move up the scope chain until we find the nearest enclosing 435 // non-transparent context. The declaration will be introduced into this 436 // scope. 437 while (S->getEntity() && 438 ((DeclContext *)S->getEntity())->isTransparentContext()) 439 S = S->getParent(); 440 441 // Add scoped declarations into their context, so that they can be 442 // found later. Declarations without a context won't be inserted 443 // into any context. 444 if (AddToContext) 445 CurContext->addDecl(D); 446 447 // Out-of-line definitions shouldn't be pushed into scope in C++. 448 // Out-of-line variable and function definitions shouldn't even in C. 449 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 450 D->isOutOfLine()) 451 return; 452 453 // Template instantiations should also not be pushed into scope. 454 if (isa<FunctionDecl>(D) && 455 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 456 return; 457 458 // If this replaces anything in the current scope, 459 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 460 IEnd = IdResolver.end(); 461 for (; I != IEnd; ++I) { 462 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 463 S->RemoveDecl(*I); 464 IdResolver.RemoveDecl(*I); 465 466 // Should only need to replace one decl. 467 break; 468 } 469 } 470 471 S->AddDecl(D); 472 IdResolver.AddDecl(D); 473} 474 475bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 476 return IdResolver.isDeclInScope(D, Ctx, Context, S); 477} 478 479Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 480 DeclContext *TargetDC = DC->getPrimaryContext(); 481 do { 482 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 483 if (ScopeDC->getPrimaryContext() == TargetDC) 484 return S; 485 } while ((S = S->getParent())); 486 487 return 0; 488} 489 490static bool isOutOfScopePreviousDeclaration(NamedDecl *, 491 DeclContext*, 492 ASTContext&); 493 494/// Filters out lookup results that don't fall within the given scope 495/// as determined by isDeclInScope. 496static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 497 DeclContext *Ctx, Scope *S, 498 bool ConsiderLinkage) { 499 LookupResult::Filter F = R.makeFilter(); 500 while (F.hasNext()) { 501 NamedDecl *D = F.next(); 502 503 if (SemaRef.isDeclInScope(D, Ctx, S)) 504 continue; 505 506 if (ConsiderLinkage && 507 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 508 continue; 509 510 F.erase(); 511 } 512 513 F.done(); 514} 515 516static bool isUsingDecl(NamedDecl *D) { 517 return isa<UsingShadowDecl>(D) || 518 isa<UnresolvedUsingTypenameDecl>(D) || 519 isa<UnresolvedUsingValueDecl>(D); 520} 521 522/// Removes using shadow declarations from the lookup results. 523static void RemoveUsingDecls(LookupResult &R) { 524 LookupResult::Filter F = R.makeFilter(); 525 while (F.hasNext()) 526 if (isUsingDecl(F.next())) 527 F.erase(); 528 529 F.done(); 530} 531 532/// \brief Check for this common pattern: 533/// @code 534/// class S { 535/// S(const S&); // DO NOT IMPLEMENT 536/// void operator=(const S&); // DO NOT IMPLEMENT 537/// }; 538/// @endcode 539static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 540 // FIXME: Should check for private access too but access is set after we get 541 // the decl here. 542 if (D->isThisDeclarationADefinition()) 543 return false; 544 545 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 546 return CD->isCopyConstructor(); 547 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 548 return Method->isCopyAssignmentOperator(); 549 return false; 550} 551 552bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 553 assert(D); 554 555 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 556 return false; 557 558 // Ignore class templates. 559 if (D->getDeclContext()->isDependentContext()) 560 return false; 561 562 // We warn for unused decls internal to the translation unit. 563 if (D->getLinkage() == ExternalLinkage) 564 return false; 565 566 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 567 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 568 return false; 569 570 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 571 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 572 return false; 573 } else { 574 // 'static inline' functions are used in headers; don't warn. 575 if (FD->getStorageClass() == SC_Static && 576 FD->isInlineSpecified()) 577 return false; 578 } 579 580 if (FD->isThisDeclarationADefinition()) 581 return !Context.DeclMustBeEmitted(FD); 582 return true; 583 } 584 585 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 586 if (VD->isStaticDataMember() && 587 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 588 return false; 589 590 if ( VD->isFileVarDecl() && 591 !VD->getType().isConstant(Context)) 592 return !Context.DeclMustBeEmitted(VD); 593 } 594 595 return false; 596 } 597 598 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 599 if (!D) 600 return; 601 602 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 603 const FunctionDecl *First = FD->getFirstDeclaration(); 604 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 605 return; // First should already be in the vector. 606 } 607 608 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 609 const VarDecl *First = VD->getFirstDeclaration(); 610 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 611 return; // First should already be in the vector. 612 } 613 614 if (ShouldWarnIfUnusedFileScopedDecl(D)) 615 UnusedFileScopedDecls.push_back(D); 616 } 617 618static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 619 if (D->isInvalidDecl()) 620 return false; 621 622 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 623 return false; 624 625 // White-list anything that isn't a local variable. 626 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 627 !D->getDeclContext()->isFunctionOrMethod()) 628 return false; 629 630 // Types of valid local variables should be complete, so this should succeed. 631 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 632 633 // White-list anything with an __attribute__((unused)) type. 634 QualType Ty = VD->getType(); 635 636 // Only look at the outermost level of typedef. 637 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 638 if (TT->getDecl()->hasAttr<UnusedAttr>()) 639 return false; 640 } 641 642 // If we failed to complete the type for some reason, or if the type is 643 // dependent, don't diagnose the variable. 644 if (Ty->isIncompleteType() || Ty->isDependentType()) 645 return false; 646 647 if (const TagType *TT = Ty->getAs<TagType>()) { 648 const TagDecl *Tag = TT->getDecl(); 649 if (Tag->hasAttr<UnusedAttr>()) 650 return false; 651 652 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 653 // FIXME: Checking for the presence of a user-declared constructor 654 // isn't completely accurate; we'd prefer to check that the initializer 655 // has no side effects. 656 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 657 return false; 658 } 659 } 660 661 // TODO: __attribute__((unused)) templates? 662 } 663 664 return true; 665} 666 667void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 668 if (!ShouldDiagnoseUnusedDecl(D)) 669 return; 670 671 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 672 Diag(D->getLocation(), diag::warn_unused_exception_param) 673 << D->getDeclName(); 674 else 675 Diag(D->getLocation(), diag::warn_unused_variable) 676 << D->getDeclName(); 677} 678 679void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 680 if (S->decl_empty()) return; 681 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 682 "Scope shouldn't contain decls!"); 683 684 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 685 I != E; ++I) { 686 Decl *TmpD = (*I); 687 assert(TmpD && "This decl didn't get pushed??"); 688 689 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 690 NamedDecl *D = cast<NamedDecl>(TmpD); 691 692 if (!D->getDeclName()) continue; 693 694 // Diagnose unused variables in this scope. 695 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 696 DiagnoseUnusedDecl(D); 697 698 // Remove this name from our lexical scope. 699 IdResolver.RemoveDecl(D); 700 } 701} 702 703/// \brief Look for an Objective-C class in the translation unit. 704/// 705/// \param Id The name of the Objective-C class we're looking for. If 706/// typo-correction fixes this name, the Id will be updated 707/// to the fixed name. 708/// 709/// \param IdLoc The location of the name in the translation unit. 710/// 711/// \param TypoCorrection If true, this routine will attempt typo correction 712/// if there is no class with the given name. 713/// 714/// \returns The declaration of the named Objective-C class, or NULL if the 715/// class could not be found. 716ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 717 SourceLocation IdLoc, 718 bool TypoCorrection) { 719 // The third "scope" argument is 0 since we aren't enabling lazy built-in 720 // creation from this context. 721 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 722 723 if (!IDecl && TypoCorrection) { 724 // Perform typo correction at the given location, but only if we 725 // find an Objective-C class name. 726 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 727 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 728 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 729 Diag(IdLoc, diag::err_undef_interface_suggest) 730 << Id << IDecl->getDeclName() 731 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 732 Diag(IDecl->getLocation(), diag::note_previous_decl) 733 << IDecl->getDeclName(); 734 735 Id = IDecl->getIdentifier(); 736 } 737 } 738 739 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 740} 741 742/// getNonFieldDeclScope - Retrieves the innermost scope, starting 743/// from S, where a non-field would be declared. This routine copes 744/// with the difference between C and C++ scoping rules in structs and 745/// unions. For example, the following code is well-formed in C but 746/// ill-formed in C++: 747/// @code 748/// struct S6 { 749/// enum { BAR } e; 750/// }; 751/// 752/// void test_S6() { 753/// struct S6 a; 754/// a.e = BAR; 755/// } 756/// @endcode 757/// For the declaration of BAR, this routine will return a different 758/// scope. The scope S will be the scope of the unnamed enumeration 759/// within S6. In C++, this routine will return the scope associated 760/// with S6, because the enumeration's scope is a transparent 761/// context but structures can contain non-field names. In C, this 762/// routine will return the translation unit scope, since the 763/// enumeration's scope is a transparent context and structures cannot 764/// contain non-field names. 765Scope *Sema::getNonFieldDeclScope(Scope *S) { 766 while (((S->getFlags() & Scope::DeclScope) == 0) || 767 (S->getEntity() && 768 ((DeclContext *)S->getEntity())->isTransparentContext()) || 769 (S->isClassScope() && !getLangOptions().CPlusPlus)) 770 S = S->getParent(); 771 return S; 772} 773 774/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 775/// file scope. lazily create a decl for it. ForRedeclaration is true 776/// if we're creating this built-in in anticipation of redeclaring the 777/// built-in. 778NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 779 Scope *S, bool ForRedeclaration, 780 SourceLocation Loc) { 781 Builtin::ID BID = (Builtin::ID)bid; 782 783 ASTContext::GetBuiltinTypeError Error; 784 QualType R = Context.GetBuiltinType(BID, Error); 785 switch (Error) { 786 case ASTContext::GE_None: 787 // Okay 788 break; 789 790 case ASTContext::GE_Missing_stdio: 791 if (ForRedeclaration) 792 Diag(Loc, diag::err_implicit_decl_requires_stdio) 793 << Context.BuiltinInfo.GetName(BID); 794 return 0; 795 796 case ASTContext::GE_Missing_setjmp: 797 if (ForRedeclaration) 798 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 799 << Context.BuiltinInfo.GetName(BID); 800 return 0; 801 } 802 803 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 804 Diag(Loc, diag::ext_implicit_lib_function_decl) 805 << Context.BuiltinInfo.GetName(BID) 806 << R; 807 if (Context.BuiltinInfo.getHeaderName(BID) && 808 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 809 != Diagnostic::Ignored) 810 Diag(Loc, diag::note_please_include_header) 811 << Context.BuiltinInfo.getHeaderName(BID) 812 << Context.BuiltinInfo.GetName(BID); 813 } 814 815 FunctionDecl *New = FunctionDecl::Create(Context, 816 Context.getTranslationUnitDecl(), 817 Loc, II, R, /*TInfo=*/0, 818 SC_Extern, 819 SC_None, false, 820 /*hasPrototype=*/true); 821 New->setImplicit(); 822 823 // Create Decl objects for each parameter, adding them to the 824 // FunctionDecl. 825 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 826 llvm::SmallVector<ParmVarDecl*, 16> Params; 827 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 828 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 829 FT->getArgType(i), /*TInfo=*/0, 830 SC_None, SC_None, 0)); 831 New->setParams(Params.data(), Params.size()); 832 } 833 834 AddKnownFunctionAttributes(New); 835 836 // TUScope is the translation-unit scope to insert this function into. 837 // FIXME: This is hideous. We need to teach PushOnScopeChains to 838 // relate Scopes to DeclContexts, and probably eliminate CurContext 839 // entirely, but we're not there yet. 840 DeclContext *SavedContext = CurContext; 841 CurContext = Context.getTranslationUnitDecl(); 842 PushOnScopeChains(New, TUScope); 843 CurContext = SavedContext; 844 return New; 845} 846 847/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 848/// same name and scope as a previous declaration 'Old'. Figure out 849/// how to resolve this situation, merging decls or emitting 850/// diagnostics as appropriate. If there was an error, set New to be invalid. 851/// 852void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 853 // If the new decl is known invalid already, don't bother doing any 854 // merging checks. 855 if (New->isInvalidDecl()) return; 856 857 // Allow multiple definitions for ObjC built-in typedefs. 858 // FIXME: Verify the underlying types are equivalent! 859 if (getLangOptions().ObjC1) { 860 const IdentifierInfo *TypeID = New->getIdentifier(); 861 switch (TypeID->getLength()) { 862 default: break; 863 case 2: 864 if (!TypeID->isStr("id")) 865 break; 866 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 867 // Install the built-in type for 'id', ignoring the current definition. 868 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 869 return; 870 case 5: 871 if (!TypeID->isStr("Class")) 872 break; 873 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 874 // Install the built-in type for 'Class', ignoring the current definition. 875 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 876 return; 877 case 3: 878 if (!TypeID->isStr("SEL")) 879 break; 880 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 881 // Install the built-in type for 'SEL', ignoring the current definition. 882 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 883 return; 884 case 8: 885 if (!TypeID->isStr("Protocol")) 886 break; 887 Context.setObjCProtoType(New->getUnderlyingType()); 888 return; 889 } 890 // Fall through - the typedef name was not a builtin type. 891 } 892 893 // Verify the old decl was also a type. 894 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 895 if (!Old) { 896 Diag(New->getLocation(), diag::err_redefinition_different_kind) 897 << New->getDeclName(); 898 899 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 900 if (OldD->getLocation().isValid()) 901 Diag(OldD->getLocation(), diag::note_previous_definition); 902 903 return New->setInvalidDecl(); 904 } 905 906 // If the old declaration is invalid, just give up here. 907 if (Old->isInvalidDecl()) 908 return New->setInvalidDecl(); 909 910 // Determine the "old" type we'll use for checking and diagnostics. 911 QualType OldType; 912 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 913 OldType = OldTypedef->getUnderlyingType(); 914 else 915 OldType = Context.getTypeDeclType(Old); 916 917 // If the typedef types are not identical, reject them in all languages and 918 // with any extensions enabled. 919 920 if (OldType != New->getUnderlyingType() && 921 Context.getCanonicalType(OldType) != 922 Context.getCanonicalType(New->getUnderlyingType())) { 923 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 924 << New->getUnderlyingType() << OldType; 925 if (Old->getLocation().isValid()) 926 Diag(Old->getLocation(), diag::note_previous_definition); 927 return New->setInvalidDecl(); 928 } 929 930 // The types match. Link up the redeclaration chain if the old 931 // declaration was a typedef. 932 // FIXME: this is a potential source of wierdness if the type 933 // spellings don't match exactly. 934 if (isa<TypedefDecl>(Old)) 935 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 936 937 if (getLangOptions().Microsoft) 938 return; 939 940 if (getLangOptions().CPlusPlus) { 941 // C++ [dcl.typedef]p2: 942 // In a given non-class scope, a typedef specifier can be used to 943 // redefine the name of any type declared in that scope to refer 944 // to the type to which it already refers. 945 if (!isa<CXXRecordDecl>(CurContext)) 946 return; 947 948 // C++0x [dcl.typedef]p4: 949 // In a given class scope, a typedef specifier can be used to redefine 950 // any class-name declared in that scope that is not also a typedef-name 951 // to refer to the type to which it already refers. 952 // 953 // This wording came in via DR424, which was a correction to the 954 // wording in DR56, which accidentally banned code like: 955 // 956 // struct S { 957 // typedef struct A { } A; 958 // }; 959 // 960 // in the C++03 standard. We implement the C++0x semantics, which 961 // allow the above but disallow 962 // 963 // struct S { 964 // typedef int I; 965 // typedef int I; 966 // }; 967 // 968 // since that was the intent of DR56. 969 if (!isa<TypedefDecl >(Old)) 970 return; 971 972 Diag(New->getLocation(), diag::err_redefinition) 973 << New->getDeclName(); 974 Diag(Old->getLocation(), diag::note_previous_definition); 975 return New->setInvalidDecl(); 976 } 977 978 // If we have a redefinition of a typedef in C, emit a warning. This warning 979 // is normally mapped to an error, but can be controlled with 980 // -Wtypedef-redefinition. If either the original or the redefinition is 981 // in a system header, don't emit this for compatibility with GCC. 982 if (getDiagnostics().getSuppressSystemWarnings() && 983 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 984 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 985 return; 986 987 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 988 << New->getDeclName(); 989 Diag(Old->getLocation(), diag::note_previous_definition); 990 return; 991} 992 993/// DeclhasAttr - returns true if decl Declaration already has the target 994/// attribute. 995static bool 996DeclHasAttr(const Decl *D, const Attr *A) { 997 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 998 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 999 if ((*i)->getKind() == A->getKind()) { 1000 // FIXME: Don't hardcode this check 1001 if (OA && isa<OwnershipAttr>(*i)) 1002 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1003 return true; 1004 } 1005 1006 return false; 1007} 1008 1009/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1010static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1011 if (!Old->hasAttrs()) 1012 return; 1013 // Ensure that any moving of objects within the allocated map is done before 1014 // we process them. 1015 if (!New->hasAttrs()) 1016 New->setAttrs(AttrVec()); 1017 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1018 ++i) { 1019 // FIXME: Make this more general than just checking for Overloadable. 1020 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1021 Attr *NewAttr = (*i)->clone(C); 1022 NewAttr->setInherited(true); 1023 New->addAttr(NewAttr); 1024 } 1025 } 1026} 1027 1028namespace { 1029 1030/// Used in MergeFunctionDecl to keep track of function parameters in 1031/// C. 1032struct GNUCompatibleParamWarning { 1033 ParmVarDecl *OldParm; 1034 ParmVarDecl *NewParm; 1035 QualType PromotedType; 1036}; 1037 1038} 1039 1040/// getSpecialMember - get the special member enum for a method. 1041Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1042 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1043 if (Ctor->isCopyConstructor()) 1044 return Sema::CXXCopyConstructor; 1045 1046 return Sema::CXXConstructor; 1047 } 1048 1049 if (isa<CXXDestructorDecl>(MD)) 1050 return Sema::CXXDestructor; 1051 1052 assert(MD->isCopyAssignmentOperator() && 1053 "Must have copy assignment operator"); 1054 return Sema::CXXCopyAssignment; 1055} 1056 1057/// canRedefineFunction - checks if a function can be redefined. Currently, 1058/// only extern inline functions can be redefined, and even then only in 1059/// GNU89 mode. 1060static bool canRedefineFunction(const FunctionDecl *FD, 1061 const LangOptions& LangOpts) { 1062 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1063 FD->isInlineSpecified() && 1064 FD->getStorageClass() == SC_Extern); 1065} 1066 1067/// MergeFunctionDecl - We just parsed a function 'New' from 1068/// declarator D which has the same name and scope as a previous 1069/// declaration 'Old'. Figure out how to resolve this situation, 1070/// merging decls or emitting diagnostics as appropriate. 1071/// 1072/// In C++, New and Old must be declarations that are not 1073/// overloaded. Use IsOverload to determine whether New and Old are 1074/// overloaded, and to select the Old declaration that New should be 1075/// merged with. 1076/// 1077/// Returns true if there was an error, false otherwise. 1078bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1079 // Verify the old decl was also a function. 1080 FunctionDecl *Old = 0; 1081 if (FunctionTemplateDecl *OldFunctionTemplate 1082 = dyn_cast<FunctionTemplateDecl>(OldD)) 1083 Old = OldFunctionTemplate->getTemplatedDecl(); 1084 else 1085 Old = dyn_cast<FunctionDecl>(OldD); 1086 if (!Old) { 1087 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1088 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1089 Diag(Shadow->getTargetDecl()->getLocation(), 1090 diag::note_using_decl_target); 1091 Diag(Shadow->getUsingDecl()->getLocation(), 1092 diag::note_using_decl) << 0; 1093 return true; 1094 } 1095 1096 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1097 << New->getDeclName(); 1098 Diag(OldD->getLocation(), diag::note_previous_definition); 1099 return true; 1100 } 1101 1102 // Determine whether the previous declaration was a definition, 1103 // implicit declaration, or a declaration. 1104 diag::kind PrevDiag; 1105 if (Old->isThisDeclarationADefinition()) 1106 PrevDiag = diag::note_previous_definition; 1107 else if (Old->isImplicit()) 1108 PrevDiag = diag::note_previous_implicit_declaration; 1109 else 1110 PrevDiag = diag::note_previous_declaration; 1111 1112 QualType OldQType = Context.getCanonicalType(Old->getType()); 1113 QualType NewQType = Context.getCanonicalType(New->getType()); 1114 1115 // Don't complain about this if we're in GNU89 mode and the old function 1116 // is an extern inline function. 1117 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1118 New->getStorageClass() == SC_Static && 1119 Old->getStorageClass() != SC_Static && 1120 !canRedefineFunction(Old, getLangOptions())) { 1121 Diag(New->getLocation(), diag::err_static_non_static) 1122 << New; 1123 Diag(Old->getLocation(), PrevDiag); 1124 return true; 1125 } 1126 1127 // If a function is first declared with a calling convention, but is 1128 // later declared or defined without one, the second decl assumes the 1129 // calling convention of the first. 1130 // 1131 // For the new decl, we have to look at the NON-canonical type to tell the 1132 // difference between a function that really doesn't have a calling 1133 // convention and one that is declared cdecl. That's because in 1134 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1135 // because it is the default calling convention. 1136 // 1137 // Note also that we DO NOT return at this point, because we still have 1138 // other tests to run. 1139 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1140 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1141 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1142 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1143 if (OldTypeInfo.getCC() != CC_Default && 1144 NewTypeInfo.getCC() == CC_Default) { 1145 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1146 New->setType(NewQType); 1147 NewQType = Context.getCanonicalType(NewQType); 1148 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1149 NewTypeInfo.getCC())) { 1150 // Calling conventions really aren't compatible, so complain. 1151 Diag(New->getLocation(), diag::err_cconv_change) 1152 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1153 << (OldTypeInfo.getCC() == CC_Default) 1154 << (OldTypeInfo.getCC() == CC_Default ? "" : 1155 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1156 Diag(Old->getLocation(), diag::note_previous_declaration); 1157 return true; 1158 } 1159 1160 // FIXME: diagnose the other way around? 1161 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1162 NewQType = Context.getNoReturnType(NewQType); 1163 New->setType(NewQType); 1164 assert(NewQType.isCanonical()); 1165 } 1166 1167 // Merge regparm attribute. 1168 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1169 if (NewType->getRegParmType()) { 1170 Diag(New->getLocation(), diag::err_regparm_mismatch) 1171 << NewType->getRegParmType() 1172 << OldType->getRegParmType(); 1173 Diag(Old->getLocation(), diag::note_previous_declaration); 1174 return true; 1175 } 1176 1177 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1178 New->setType(NewQType); 1179 assert(NewQType.isCanonical()); 1180 } 1181 1182 if (getLangOptions().CPlusPlus) { 1183 // (C++98 13.1p2): 1184 // Certain function declarations cannot be overloaded: 1185 // -- Function declarations that differ only in the return type 1186 // cannot be overloaded. 1187 QualType OldReturnType 1188 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1189 QualType NewReturnType 1190 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1191 QualType ResQT; 1192 if (OldReturnType != NewReturnType) { 1193 if (NewReturnType->isObjCObjectPointerType() 1194 && OldReturnType->isObjCObjectPointerType()) 1195 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1196 if (ResQT.isNull()) { 1197 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1198 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1199 return true; 1200 } 1201 else 1202 NewQType = ResQT; 1203 } 1204 1205 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1206 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1207 if (OldMethod && NewMethod) { 1208 // Preserve triviality. 1209 NewMethod->setTrivial(OldMethod->isTrivial()); 1210 1211 bool isFriend = NewMethod->getFriendObjectKind(); 1212 1213 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1214 // -- Member function declarations with the same name and the 1215 // same parameter types cannot be overloaded if any of them 1216 // is a static member function declaration. 1217 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1218 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1219 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1220 return true; 1221 } 1222 1223 // C++ [class.mem]p1: 1224 // [...] A member shall not be declared twice in the 1225 // member-specification, except that a nested class or member 1226 // class template can be declared and then later defined. 1227 unsigned NewDiag; 1228 if (isa<CXXConstructorDecl>(OldMethod)) 1229 NewDiag = diag::err_constructor_redeclared; 1230 else if (isa<CXXDestructorDecl>(NewMethod)) 1231 NewDiag = diag::err_destructor_redeclared; 1232 else if (isa<CXXConversionDecl>(NewMethod)) 1233 NewDiag = diag::err_conv_function_redeclared; 1234 else 1235 NewDiag = diag::err_member_redeclared; 1236 1237 Diag(New->getLocation(), NewDiag); 1238 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1239 1240 // Complain if this is an explicit declaration of a special 1241 // member that was initially declared implicitly. 1242 // 1243 // As an exception, it's okay to befriend such methods in order 1244 // to permit the implicit constructor/destructor/operator calls. 1245 } else if (OldMethod->isImplicit()) { 1246 if (isFriend) { 1247 NewMethod->setImplicit(); 1248 } else { 1249 Diag(NewMethod->getLocation(), 1250 diag::err_definition_of_implicitly_declared_member) 1251 << New << getSpecialMember(OldMethod); 1252 return true; 1253 } 1254 } 1255 } 1256 1257 // (C++98 8.3.5p3): 1258 // All declarations for a function shall agree exactly in both the 1259 // return type and the parameter-type-list. 1260 // attributes should be ignored when comparing. 1261 if (Context.getNoReturnType(OldQType, false) == 1262 Context.getNoReturnType(NewQType, false)) 1263 return MergeCompatibleFunctionDecls(New, Old); 1264 1265 // Fall through for conflicting redeclarations and redefinitions. 1266 } 1267 1268 // C: Function types need to be compatible, not identical. This handles 1269 // duplicate function decls like "void f(int); void f(enum X);" properly. 1270 if (!getLangOptions().CPlusPlus && 1271 Context.typesAreCompatible(OldQType, NewQType)) { 1272 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1273 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1274 const FunctionProtoType *OldProto = 0; 1275 if (isa<FunctionNoProtoType>(NewFuncType) && 1276 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1277 // The old declaration provided a function prototype, but the 1278 // new declaration does not. Merge in the prototype. 1279 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1280 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1281 OldProto->arg_type_end()); 1282 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1283 ParamTypes.data(), ParamTypes.size(), 1284 OldProto->isVariadic(), 1285 OldProto->getTypeQuals(), 1286 false, false, 0, 0, 1287 OldProto->getExtInfo()); 1288 New->setType(NewQType); 1289 New->setHasInheritedPrototype(); 1290 1291 // Synthesize a parameter for each argument type. 1292 llvm::SmallVector<ParmVarDecl*, 16> Params; 1293 for (FunctionProtoType::arg_type_iterator 1294 ParamType = OldProto->arg_type_begin(), 1295 ParamEnd = OldProto->arg_type_end(); 1296 ParamType != ParamEnd; ++ParamType) { 1297 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1298 SourceLocation(), 0, 1299 *ParamType, /*TInfo=*/0, 1300 SC_None, SC_None, 1301 0); 1302 Param->setImplicit(); 1303 Params.push_back(Param); 1304 } 1305 1306 New->setParams(Params.data(), Params.size()); 1307 } 1308 1309 return MergeCompatibleFunctionDecls(New, Old); 1310 } 1311 1312 // GNU C permits a K&R definition to follow a prototype declaration 1313 // if the declared types of the parameters in the K&R definition 1314 // match the types in the prototype declaration, even when the 1315 // promoted types of the parameters from the K&R definition differ 1316 // from the types in the prototype. GCC then keeps the types from 1317 // the prototype. 1318 // 1319 // If a variadic prototype is followed by a non-variadic K&R definition, 1320 // the K&R definition becomes variadic. This is sort of an edge case, but 1321 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1322 // C99 6.9.1p8. 1323 if (!getLangOptions().CPlusPlus && 1324 Old->hasPrototype() && !New->hasPrototype() && 1325 New->getType()->getAs<FunctionProtoType>() && 1326 Old->getNumParams() == New->getNumParams()) { 1327 llvm::SmallVector<QualType, 16> ArgTypes; 1328 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1329 const FunctionProtoType *OldProto 1330 = Old->getType()->getAs<FunctionProtoType>(); 1331 const FunctionProtoType *NewProto 1332 = New->getType()->getAs<FunctionProtoType>(); 1333 1334 // Determine whether this is the GNU C extension. 1335 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1336 NewProto->getResultType()); 1337 bool LooseCompatible = !MergedReturn.isNull(); 1338 for (unsigned Idx = 0, End = Old->getNumParams(); 1339 LooseCompatible && Idx != End; ++Idx) { 1340 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1341 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1342 if (Context.typesAreCompatible(OldParm->getType(), 1343 NewProto->getArgType(Idx))) { 1344 ArgTypes.push_back(NewParm->getType()); 1345 } else if (Context.typesAreCompatible(OldParm->getType(), 1346 NewParm->getType(), 1347 /*CompareUnqualified=*/true)) { 1348 GNUCompatibleParamWarning Warn 1349 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1350 Warnings.push_back(Warn); 1351 ArgTypes.push_back(NewParm->getType()); 1352 } else 1353 LooseCompatible = false; 1354 } 1355 1356 if (LooseCompatible) { 1357 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1358 Diag(Warnings[Warn].NewParm->getLocation(), 1359 diag::ext_param_promoted_not_compatible_with_prototype) 1360 << Warnings[Warn].PromotedType 1361 << Warnings[Warn].OldParm->getType(); 1362 if (Warnings[Warn].OldParm->getLocation().isValid()) 1363 Diag(Warnings[Warn].OldParm->getLocation(), 1364 diag::note_previous_declaration); 1365 } 1366 1367 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1368 ArgTypes.size(), 1369 OldProto->isVariadic(), 0, 1370 false, false, 0, 0, 1371 OldProto->getExtInfo())); 1372 return MergeCompatibleFunctionDecls(New, Old); 1373 } 1374 1375 // Fall through to diagnose conflicting types. 1376 } 1377 1378 // A function that has already been declared has been redeclared or defined 1379 // with a different type- show appropriate diagnostic 1380 if (unsigned BuiltinID = Old->getBuiltinID()) { 1381 // The user has declared a builtin function with an incompatible 1382 // signature. 1383 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1384 // The function the user is redeclaring is a library-defined 1385 // function like 'malloc' or 'printf'. Warn about the 1386 // redeclaration, then pretend that we don't know about this 1387 // library built-in. 1388 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1389 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1390 << Old << Old->getType(); 1391 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1392 Old->setInvalidDecl(); 1393 return false; 1394 } 1395 1396 PrevDiag = diag::note_previous_builtin_declaration; 1397 } 1398 1399 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1400 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1401 return true; 1402} 1403 1404/// \brief Completes the merge of two function declarations that are 1405/// known to be compatible. 1406/// 1407/// This routine handles the merging of attributes and other 1408/// properties of function declarations form the old declaration to 1409/// the new declaration, once we know that New is in fact a 1410/// redeclaration of Old. 1411/// 1412/// \returns false 1413bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1414 // Merge the attributes 1415 MergeDeclAttributes(New, Old, Context); 1416 1417 // Merge the storage class. 1418 if (Old->getStorageClass() != SC_Extern && 1419 Old->getStorageClass() != SC_None) 1420 New->setStorageClass(Old->getStorageClass()); 1421 1422 // Merge "pure" flag. 1423 if (Old->isPure()) 1424 New->setPure(); 1425 1426 // Merge the "deleted" flag. 1427 if (Old->isDeleted()) 1428 New->setDeleted(); 1429 1430 if (getLangOptions().CPlusPlus) 1431 return MergeCXXFunctionDecl(New, Old); 1432 1433 return false; 1434} 1435 1436/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1437/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1438/// situation, merging decls or emitting diagnostics as appropriate. 1439/// 1440/// Tentative definition rules (C99 6.9.2p2) are checked by 1441/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1442/// definitions here, since the initializer hasn't been attached. 1443/// 1444void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1445 // If the new decl is already invalid, don't do any other checking. 1446 if (New->isInvalidDecl()) 1447 return; 1448 1449 // Verify the old decl was also a variable. 1450 VarDecl *Old = 0; 1451 if (!Previous.isSingleResult() || 1452 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1453 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1454 << New->getDeclName(); 1455 Diag(Previous.getRepresentativeDecl()->getLocation(), 1456 diag::note_previous_definition); 1457 return New->setInvalidDecl(); 1458 } 1459 1460 // C++ [class.mem]p1: 1461 // A member shall not be declared twice in the member-specification [...] 1462 // 1463 // Here, we need only consider static data members. 1464 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1465 Diag(New->getLocation(), diag::err_duplicate_member) 1466 << New->getIdentifier(); 1467 Diag(Old->getLocation(), diag::note_previous_declaration); 1468 New->setInvalidDecl(); 1469 } 1470 1471 MergeDeclAttributes(New, Old, Context); 1472 1473 // Merge the types 1474 QualType MergedT; 1475 if (getLangOptions().CPlusPlus) { 1476 if (Context.hasSameType(New->getType(), Old->getType())) 1477 MergedT = New->getType(); 1478 // C++ [basic.link]p10: 1479 // [...] the types specified by all declarations referring to a given 1480 // object or function shall be identical, except that declarations for an 1481 // array object can specify array types that differ by the presence or 1482 // absence of a major array bound (8.3.4). 1483 else if (Old->getType()->isIncompleteArrayType() && 1484 New->getType()->isArrayType()) { 1485 CanQual<ArrayType> OldArray 1486 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1487 CanQual<ArrayType> NewArray 1488 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1489 if (OldArray->getElementType() == NewArray->getElementType()) 1490 MergedT = New->getType(); 1491 } else if (Old->getType()->isArrayType() && 1492 New->getType()->isIncompleteArrayType()) { 1493 CanQual<ArrayType> OldArray 1494 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1495 CanQual<ArrayType> NewArray 1496 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1497 if (OldArray->getElementType() == NewArray->getElementType()) 1498 MergedT = Old->getType(); 1499 } else if (New->getType()->isObjCObjectPointerType() 1500 && Old->getType()->isObjCObjectPointerType()) { 1501 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1502 } 1503 } else { 1504 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1505 } 1506 if (MergedT.isNull()) { 1507 Diag(New->getLocation(), diag::err_redefinition_different_type) 1508 << New->getDeclName(); 1509 Diag(Old->getLocation(), diag::note_previous_definition); 1510 return New->setInvalidDecl(); 1511 } 1512 New->setType(MergedT); 1513 1514 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1515 if (New->getStorageClass() == SC_Static && 1516 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1517 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1518 Diag(Old->getLocation(), diag::note_previous_definition); 1519 return New->setInvalidDecl(); 1520 } 1521 // C99 6.2.2p4: 1522 // For an identifier declared with the storage-class specifier 1523 // extern in a scope in which a prior declaration of that 1524 // identifier is visible,23) if the prior declaration specifies 1525 // internal or external linkage, the linkage of the identifier at 1526 // the later declaration is the same as the linkage specified at 1527 // the prior declaration. If no prior declaration is visible, or 1528 // if the prior declaration specifies no linkage, then the 1529 // identifier has external linkage. 1530 if (New->hasExternalStorage() && Old->hasLinkage()) 1531 /* Okay */; 1532 else if (New->getStorageClass() != SC_Static && 1533 Old->getStorageClass() == SC_Static) { 1534 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1535 Diag(Old->getLocation(), diag::note_previous_definition); 1536 return New->setInvalidDecl(); 1537 } 1538 1539 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1540 1541 // FIXME: The test for external storage here seems wrong? We still 1542 // need to check for mismatches. 1543 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1544 // Don't complain about out-of-line definitions of static members. 1545 !(Old->getLexicalDeclContext()->isRecord() && 1546 !New->getLexicalDeclContext()->isRecord())) { 1547 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1548 Diag(Old->getLocation(), diag::note_previous_definition); 1549 return New->setInvalidDecl(); 1550 } 1551 1552 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1553 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1554 Diag(Old->getLocation(), diag::note_previous_definition); 1555 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1556 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1557 Diag(Old->getLocation(), diag::note_previous_definition); 1558 } 1559 1560 // C++ doesn't have tentative definitions, so go right ahead and check here. 1561 const VarDecl *Def; 1562 if (getLangOptions().CPlusPlus && 1563 New->isThisDeclarationADefinition() == VarDecl::Definition && 1564 (Def = Old->getDefinition())) { 1565 Diag(New->getLocation(), diag::err_redefinition) 1566 << New->getDeclName(); 1567 Diag(Def->getLocation(), diag::note_previous_definition); 1568 New->setInvalidDecl(); 1569 return; 1570 } 1571 // c99 6.2.2 P4. 1572 // For an identifier declared with the storage-class specifier extern in a 1573 // scope in which a prior declaration of that identifier is visible, if 1574 // the prior declaration specifies internal or external linkage, the linkage 1575 // of the identifier at the later declaration is the same as the linkage 1576 // specified at the prior declaration. 1577 // FIXME. revisit this code. 1578 if (New->hasExternalStorage() && 1579 Old->getLinkage() == InternalLinkage && 1580 New->getDeclContext() == Old->getDeclContext()) 1581 New->setStorageClass(Old->getStorageClass()); 1582 1583 // Keep a chain of previous declarations. 1584 New->setPreviousDeclaration(Old); 1585 1586 // Inherit access appropriately. 1587 New->setAccess(Old->getAccess()); 1588} 1589 1590/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1591/// no declarator (e.g. "struct foo;") is parsed. 1592Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1593 DeclSpec &DS) { 1594 // FIXME: Error on inline/virtual/explicit 1595 // FIXME: Warn on useless __thread 1596 // FIXME: Warn on useless const/volatile 1597 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1598 // FIXME: Warn on useless attributes 1599 Decl *TagD = 0; 1600 TagDecl *Tag = 0; 1601 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1602 DS.getTypeSpecType() == DeclSpec::TST_struct || 1603 DS.getTypeSpecType() == DeclSpec::TST_union || 1604 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1605 TagD = DS.getRepAsDecl(); 1606 1607 if (!TagD) // We probably had an error 1608 return 0; 1609 1610 // Note that the above type specs guarantee that the 1611 // type rep is a Decl, whereas in many of the others 1612 // it's a Type. 1613 Tag = dyn_cast<TagDecl>(TagD); 1614 } 1615 1616 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1617 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1618 // or incomplete types shall not be restrict-qualified." 1619 if (TypeQuals & DeclSpec::TQ_restrict) 1620 Diag(DS.getRestrictSpecLoc(), 1621 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1622 << DS.getSourceRange(); 1623 } 1624 1625 if (DS.isFriendSpecified()) { 1626 // If we're dealing with a class template decl, assume that the 1627 // template routines are handling it. 1628 if (TagD && isa<ClassTemplateDecl>(TagD)) 1629 return 0; 1630 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1631 } 1632 1633 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1634 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1635 1636 if (!Record->getDeclName() && Record->isDefinition() && 1637 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1638 if (getLangOptions().CPlusPlus || 1639 Record->getDeclContext()->isRecord()) 1640 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1641 1642 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1643 << DS.getSourceRange(); 1644 } 1645 1646 // Microsoft allows unnamed struct/union fields. Don't complain 1647 // about them. 1648 // FIXME: Should we support Microsoft's extensions in this area? 1649 if (Record->getDeclName() && getLangOptions().Microsoft) 1650 return Tag; 1651 } 1652 1653 if (getLangOptions().CPlusPlus && 1654 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1655 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1656 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1657 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1658 Diag(Enum->getLocation(), diag::ext_no_declarators) 1659 << DS.getSourceRange(); 1660 1661 if (!DS.isMissingDeclaratorOk() && 1662 DS.getTypeSpecType() != DeclSpec::TST_error) { 1663 // Warn about typedefs of enums without names, since this is an 1664 // extension in both Microsoft and GNU. 1665 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1666 Tag && isa<EnumDecl>(Tag)) { 1667 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1668 << DS.getSourceRange(); 1669 return Tag; 1670 } 1671 1672 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1673 << DS.getSourceRange(); 1674 } 1675 1676 return TagD; 1677} 1678 1679/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1680/// builds a statement for it and returns it so it is evaluated. 1681StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1682 StmtResult R; 1683 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1684 Expr *Exp = DS.getRepAsExpr(); 1685 QualType Ty = Exp->getType(); 1686 if (Ty->isPointerType()) { 1687 do 1688 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1689 while (Ty->isPointerType()); 1690 } 1691 if (Ty->isVariableArrayType()) { 1692 R = ActOnExprStmt(MakeFullExpr(Exp)); 1693 } 1694 } 1695 return R; 1696} 1697 1698/// We are trying to inject an anonymous member into the given scope; 1699/// check if there's an existing declaration that can't be overloaded. 1700/// 1701/// \return true if this is a forbidden redeclaration 1702static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1703 Scope *S, 1704 DeclContext *Owner, 1705 DeclarationName Name, 1706 SourceLocation NameLoc, 1707 unsigned diagnostic) { 1708 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1709 Sema::ForRedeclaration); 1710 if (!SemaRef.LookupName(R, S)) return false; 1711 1712 if (R.getAsSingle<TagDecl>()) 1713 return false; 1714 1715 // Pick a representative declaration. 1716 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1717 assert(PrevDecl && "Expected a non-null Decl"); 1718 1719 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1720 return false; 1721 1722 SemaRef.Diag(NameLoc, diagnostic) << Name; 1723 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1724 1725 return true; 1726} 1727 1728/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1729/// anonymous struct or union AnonRecord into the owning context Owner 1730/// and scope S. This routine will be invoked just after we realize 1731/// that an unnamed union or struct is actually an anonymous union or 1732/// struct, e.g., 1733/// 1734/// @code 1735/// union { 1736/// int i; 1737/// float f; 1738/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1739/// // f into the surrounding scope.x 1740/// @endcode 1741/// 1742/// This routine is recursive, injecting the names of nested anonymous 1743/// structs/unions into the owning context and scope as well. 1744static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1745 DeclContext *Owner, 1746 RecordDecl *AnonRecord, 1747 AccessSpecifier AS) { 1748 unsigned diagKind 1749 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1750 : diag::err_anonymous_struct_member_redecl; 1751 1752 bool Invalid = false; 1753 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1754 FEnd = AnonRecord->field_end(); 1755 F != FEnd; ++F) { 1756 if ((*F)->getDeclName()) { 1757 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1758 (*F)->getLocation(), diagKind)) { 1759 // C++ [class.union]p2: 1760 // The names of the members of an anonymous union shall be 1761 // distinct from the names of any other entity in the 1762 // scope in which the anonymous union is declared. 1763 Invalid = true; 1764 } else { 1765 // C++ [class.union]p2: 1766 // For the purpose of name lookup, after the anonymous union 1767 // definition, the members of the anonymous union are 1768 // considered to have been defined in the scope in which the 1769 // anonymous union is declared. 1770 Owner->makeDeclVisibleInContext(*F); 1771 S->AddDecl(*F); 1772 SemaRef.IdResolver.AddDecl(*F); 1773 1774 // That includes picking up the appropriate access specifier. 1775 if (AS != AS_none) (*F)->setAccess(AS); 1776 } 1777 } else if (const RecordType *InnerRecordType 1778 = (*F)->getType()->getAs<RecordType>()) { 1779 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1780 if (InnerRecord->isAnonymousStructOrUnion()) 1781 Invalid = Invalid || 1782 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1783 InnerRecord, AS); 1784 } 1785 } 1786 1787 return Invalid; 1788} 1789 1790/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1791/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1792/// illegal input values are mapped to SC_None. 1793static StorageClass 1794StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1795 switch (StorageClassSpec) { 1796 case DeclSpec::SCS_unspecified: return SC_None; 1797 case DeclSpec::SCS_extern: return SC_Extern; 1798 case DeclSpec::SCS_static: return SC_Static; 1799 case DeclSpec::SCS_auto: return SC_Auto; 1800 case DeclSpec::SCS_register: return SC_Register; 1801 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1802 // Illegal SCSs map to None: error reporting is up to the caller. 1803 case DeclSpec::SCS_mutable: // Fall through. 1804 case DeclSpec::SCS_typedef: return SC_None; 1805 } 1806 llvm_unreachable("unknown storage class specifier"); 1807} 1808 1809/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1810/// a StorageClass. Any error reporting is up to the caller: 1811/// illegal input values are mapped to SC_None. 1812static StorageClass 1813StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1814 switch (StorageClassSpec) { 1815 case DeclSpec::SCS_unspecified: return SC_None; 1816 case DeclSpec::SCS_extern: return SC_Extern; 1817 case DeclSpec::SCS_static: return SC_Static; 1818 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1819 // Illegal SCSs map to None: error reporting is up to the caller. 1820 case DeclSpec::SCS_auto: // Fall through. 1821 case DeclSpec::SCS_mutable: // Fall through. 1822 case DeclSpec::SCS_register: // Fall through. 1823 case DeclSpec::SCS_typedef: return SC_None; 1824 } 1825 llvm_unreachable("unknown storage class specifier"); 1826} 1827 1828/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1829/// anonymous structure or union. Anonymous unions are a C++ feature 1830/// (C++ [class.union]) and a GNU C extension; anonymous structures 1831/// are a GNU C and GNU C++ extension. 1832Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1833 AccessSpecifier AS, 1834 RecordDecl *Record) { 1835 DeclContext *Owner = Record->getDeclContext(); 1836 1837 // Diagnose whether this anonymous struct/union is an extension. 1838 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1839 Diag(Record->getLocation(), diag::ext_anonymous_union); 1840 else if (!Record->isUnion()) 1841 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1842 1843 // C and C++ require different kinds of checks for anonymous 1844 // structs/unions. 1845 bool Invalid = false; 1846 if (getLangOptions().CPlusPlus) { 1847 const char* PrevSpec = 0; 1848 unsigned DiagID; 1849 // C++ [class.union]p3: 1850 // Anonymous unions declared in a named namespace or in the 1851 // global namespace shall be declared static. 1852 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1853 (isa<TranslationUnitDecl>(Owner) || 1854 (isa<NamespaceDecl>(Owner) && 1855 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1856 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1857 Invalid = true; 1858 1859 // Recover by adding 'static'. 1860 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1861 PrevSpec, DiagID); 1862 } 1863 // C++ [class.union]p3: 1864 // A storage class is not allowed in a declaration of an 1865 // anonymous union in a class scope. 1866 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1867 isa<RecordDecl>(Owner)) { 1868 Diag(DS.getStorageClassSpecLoc(), 1869 diag::err_anonymous_union_with_storage_spec); 1870 Invalid = true; 1871 1872 // Recover by removing the storage specifier. 1873 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1874 PrevSpec, DiagID); 1875 } 1876 1877 // C++ [class.union]p2: 1878 // The member-specification of an anonymous union shall only 1879 // define non-static data members. [Note: nested types and 1880 // functions cannot be declared within an anonymous union. ] 1881 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1882 MemEnd = Record->decls_end(); 1883 Mem != MemEnd; ++Mem) { 1884 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1885 // C++ [class.union]p3: 1886 // An anonymous union shall not have private or protected 1887 // members (clause 11). 1888 assert(FD->getAccess() != AS_none); 1889 if (FD->getAccess() != AS_public) { 1890 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1891 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1892 Invalid = true; 1893 } 1894 1895 if (CheckNontrivialField(FD)) 1896 Invalid = true; 1897 } else if ((*Mem)->isImplicit()) { 1898 // Any implicit members are fine. 1899 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1900 // This is a type that showed up in an 1901 // elaborated-type-specifier inside the anonymous struct or 1902 // union, but which actually declares a type outside of the 1903 // anonymous struct or union. It's okay. 1904 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1905 if (!MemRecord->isAnonymousStructOrUnion() && 1906 MemRecord->getDeclName()) { 1907 // Visual C++ allows type definition in anonymous struct or union. 1908 if (getLangOptions().Microsoft) 1909 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 1910 << (int)Record->isUnion(); 1911 else { 1912 // This is a nested type declaration. 1913 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1914 << (int)Record->isUnion(); 1915 Invalid = true; 1916 } 1917 } 1918 } else if (isa<AccessSpecDecl>(*Mem)) { 1919 // Any access specifier is fine. 1920 } else { 1921 // We have something that isn't a non-static data 1922 // member. Complain about it. 1923 unsigned DK = diag::err_anonymous_record_bad_member; 1924 if (isa<TypeDecl>(*Mem)) 1925 DK = diag::err_anonymous_record_with_type; 1926 else if (isa<FunctionDecl>(*Mem)) 1927 DK = diag::err_anonymous_record_with_function; 1928 else if (isa<VarDecl>(*Mem)) 1929 DK = diag::err_anonymous_record_with_static; 1930 1931 // Visual C++ allows type definition in anonymous struct or union. 1932 if (getLangOptions().Microsoft && 1933 DK == diag::err_anonymous_record_with_type) 1934 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 1935 << (int)Record->isUnion(); 1936 else { 1937 Diag((*Mem)->getLocation(), DK) 1938 << (int)Record->isUnion(); 1939 Invalid = true; 1940 } 1941 } 1942 } 1943 } 1944 1945 if (!Record->isUnion() && !Owner->isRecord()) { 1946 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1947 << (int)getLangOptions().CPlusPlus; 1948 Invalid = true; 1949 } 1950 1951 // Mock up a declarator. 1952 Declarator Dc(DS, Declarator::TypeNameContext); 1953 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1954 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1955 1956 // Create a declaration for this anonymous struct/union. 1957 NamedDecl *Anon = 0; 1958 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1959 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1960 /*IdentifierInfo=*/0, 1961 Context.getTypeDeclType(Record), 1962 TInfo, 1963 /*BitWidth=*/0, /*Mutable=*/false); 1964 Anon->setAccess(AS); 1965 if (getLangOptions().CPlusPlus) 1966 FieldCollector->Add(cast<FieldDecl>(Anon)); 1967 } else { 1968 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1969 assert(SCSpec != DeclSpec::SCS_typedef && 1970 "Parser allowed 'typedef' as storage class VarDecl."); 1971 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1972 if (SCSpec == DeclSpec::SCS_mutable) { 1973 // mutable can only appear on non-static class members, so it's always 1974 // an error here 1975 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1976 Invalid = true; 1977 SC = SC_None; 1978 } 1979 SCSpec = DS.getStorageClassSpecAsWritten(); 1980 VarDecl::StorageClass SCAsWritten 1981 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1982 1983 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1984 /*IdentifierInfo=*/0, 1985 Context.getTypeDeclType(Record), 1986 TInfo, SC, SCAsWritten); 1987 } 1988 Anon->setImplicit(); 1989 1990 // Add the anonymous struct/union object to the current 1991 // context. We'll be referencing this object when we refer to one of 1992 // its members. 1993 Owner->addDecl(Anon); 1994 1995 // Inject the members of the anonymous struct/union into the owning 1996 // context and into the identifier resolver chain for name lookup 1997 // purposes. 1998 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1999 Invalid = true; 2000 2001 // Mark this as an anonymous struct/union type. Note that we do not 2002 // do this until after we have already checked and injected the 2003 // members of this anonymous struct/union type, because otherwise 2004 // the members could be injected twice: once by DeclContext when it 2005 // builds its lookup table, and once by 2006 // InjectAnonymousStructOrUnionMembers. 2007 Record->setAnonymousStructOrUnion(true); 2008 2009 if (Invalid) 2010 Anon->setInvalidDecl(); 2011 2012 return Anon; 2013} 2014 2015 2016/// GetNameForDeclarator - Determine the full declaration name for the 2017/// given Declarator. 2018DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2019 return GetNameFromUnqualifiedId(D.getName()); 2020} 2021 2022/// \brief Retrieves the declaration name from a parsed unqualified-id. 2023DeclarationNameInfo 2024Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2025 DeclarationNameInfo NameInfo; 2026 NameInfo.setLoc(Name.StartLocation); 2027 2028 switch (Name.getKind()) { 2029 2030 case UnqualifiedId::IK_Identifier: 2031 NameInfo.setName(Name.Identifier); 2032 NameInfo.setLoc(Name.StartLocation); 2033 return NameInfo; 2034 2035 case UnqualifiedId::IK_OperatorFunctionId: 2036 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2037 Name.OperatorFunctionId.Operator)); 2038 NameInfo.setLoc(Name.StartLocation); 2039 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2040 = Name.OperatorFunctionId.SymbolLocations[0]; 2041 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2042 = Name.EndLocation.getRawEncoding(); 2043 return NameInfo; 2044 2045 case UnqualifiedId::IK_LiteralOperatorId: 2046 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2047 Name.Identifier)); 2048 NameInfo.setLoc(Name.StartLocation); 2049 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2050 return NameInfo; 2051 2052 case UnqualifiedId::IK_ConversionFunctionId: { 2053 TypeSourceInfo *TInfo; 2054 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2055 if (Ty.isNull()) 2056 return DeclarationNameInfo(); 2057 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2058 Context.getCanonicalType(Ty))); 2059 NameInfo.setLoc(Name.StartLocation); 2060 NameInfo.setNamedTypeInfo(TInfo); 2061 return NameInfo; 2062 } 2063 2064 case UnqualifiedId::IK_ConstructorName: { 2065 TypeSourceInfo *TInfo; 2066 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2067 if (Ty.isNull()) 2068 return DeclarationNameInfo(); 2069 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2070 Context.getCanonicalType(Ty))); 2071 NameInfo.setLoc(Name.StartLocation); 2072 NameInfo.setNamedTypeInfo(TInfo); 2073 return NameInfo; 2074 } 2075 2076 case UnqualifiedId::IK_ConstructorTemplateId: { 2077 // In well-formed code, we can only have a constructor 2078 // template-id that refers to the current context, so go there 2079 // to find the actual type being constructed. 2080 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2081 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2082 return DeclarationNameInfo(); 2083 2084 // Determine the type of the class being constructed. 2085 QualType CurClassType = Context.getTypeDeclType(CurClass); 2086 2087 // FIXME: Check two things: that the template-id names the same type as 2088 // CurClassType, and that the template-id does not occur when the name 2089 // was qualified. 2090 2091 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2092 Context.getCanonicalType(CurClassType))); 2093 NameInfo.setLoc(Name.StartLocation); 2094 // FIXME: should we retrieve TypeSourceInfo? 2095 NameInfo.setNamedTypeInfo(0); 2096 return NameInfo; 2097 } 2098 2099 case UnqualifiedId::IK_DestructorName: { 2100 TypeSourceInfo *TInfo; 2101 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2102 if (Ty.isNull()) 2103 return DeclarationNameInfo(); 2104 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2105 Context.getCanonicalType(Ty))); 2106 NameInfo.setLoc(Name.StartLocation); 2107 NameInfo.setNamedTypeInfo(TInfo); 2108 return NameInfo; 2109 } 2110 2111 case UnqualifiedId::IK_TemplateId: { 2112 TemplateName TName = Name.TemplateId->Template.get(); 2113 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2114 return Context.getNameForTemplate(TName, TNameLoc); 2115 } 2116 2117 } // switch (Name.getKind()) 2118 2119 assert(false && "Unknown name kind"); 2120 return DeclarationNameInfo(); 2121} 2122 2123/// isNearlyMatchingFunction - Determine whether the C++ functions 2124/// Declaration and Definition are "nearly" matching. This heuristic 2125/// is used to improve diagnostics in the case where an out-of-line 2126/// function definition doesn't match any declaration within 2127/// the class or namespace. 2128static bool isNearlyMatchingFunction(ASTContext &Context, 2129 FunctionDecl *Declaration, 2130 FunctionDecl *Definition) { 2131 if (Declaration->param_size() != Definition->param_size()) 2132 return false; 2133 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2134 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2135 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2136 2137 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2138 DefParamTy.getNonReferenceType())) 2139 return false; 2140 } 2141 2142 return true; 2143} 2144 2145/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2146/// declarator needs to be rebuilt in the current instantiation. 2147/// Any bits of declarator which appear before the name are valid for 2148/// consideration here. That's specifically the type in the decl spec 2149/// and the base type in any member-pointer chunks. 2150static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2151 DeclarationName Name) { 2152 // The types we specifically need to rebuild are: 2153 // - typenames, typeofs, and decltypes 2154 // - types which will become injected class names 2155 // Of course, we also need to rebuild any type referencing such a 2156 // type. It's safest to just say "dependent", but we call out a 2157 // few cases here. 2158 2159 DeclSpec &DS = D.getMutableDeclSpec(); 2160 switch (DS.getTypeSpecType()) { 2161 case DeclSpec::TST_typename: 2162 case DeclSpec::TST_typeofType: 2163 case DeclSpec::TST_decltype: { 2164 // Grab the type from the parser. 2165 TypeSourceInfo *TSI = 0; 2166 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2167 if (T.isNull() || !T->isDependentType()) break; 2168 2169 // Make sure there's a type source info. This isn't really much 2170 // of a waste; most dependent types should have type source info 2171 // attached already. 2172 if (!TSI) 2173 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2174 2175 // Rebuild the type in the current instantiation. 2176 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2177 if (!TSI) return true; 2178 2179 // Store the new type back in the decl spec. 2180 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2181 DS.UpdateTypeRep(LocType); 2182 break; 2183 } 2184 2185 case DeclSpec::TST_typeofExpr: { 2186 Expr *E = DS.getRepAsExpr(); 2187 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2188 if (Result.isInvalid()) return true; 2189 DS.UpdateExprRep(Result.get()); 2190 break; 2191 } 2192 2193 default: 2194 // Nothing to do for these decl specs. 2195 break; 2196 } 2197 2198 // It doesn't matter what order we do this in. 2199 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2200 DeclaratorChunk &Chunk = D.getTypeObject(I); 2201 2202 // The only type information in the declarator which can come 2203 // before the declaration name is the base type of a member 2204 // pointer. 2205 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2206 continue; 2207 2208 // Rebuild the scope specifier in-place. 2209 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2210 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2211 return true; 2212 } 2213 2214 return false; 2215} 2216 2217Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2218 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2219} 2220 2221Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2222 MultiTemplateParamsArg TemplateParamLists, 2223 bool IsFunctionDefinition) { 2224 // TODO: consider using NameInfo for diagnostic. 2225 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2226 DeclarationName Name = NameInfo.getName(); 2227 2228 // All of these full declarators require an identifier. If it doesn't have 2229 // one, the ParsedFreeStandingDeclSpec action should be used. 2230 if (!Name) { 2231 if (!D.isInvalidType()) // Reject this if we think it is valid. 2232 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2233 diag::err_declarator_need_ident) 2234 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2235 return 0; 2236 } 2237 2238 // The scope passed in may not be a decl scope. Zip up the scope tree until 2239 // we find one that is. 2240 while ((S->getFlags() & Scope::DeclScope) == 0 || 2241 (S->getFlags() & Scope::TemplateParamScope) != 0) 2242 S = S->getParent(); 2243 2244 DeclContext *DC = CurContext; 2245 if (D.getCXXScopeSpec().isInvalid()) 2246 D.setInvalidType(); 2247 else if (D.getCXXScopeSpec().isSet()) { 2248 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2249 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2250 if (!DC) { 2251 // If we could not compute the declaration context, it's because the 2252 // declaration context is dependent but does not refer to a class, 2253 // class template, or class template partial specialization. Complain 2254 // and return early, to avoid the coming semantic disaster. 2255 Diag(D.getIdentifierLoc(), 2256 diag::err_template_qualified_declarator_no_match) 2257 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2258 << D.getCXXScopeSpec().getRange(); 2259 return 0; 2260 } 2261 2262 bool IsDependentContext = DC->isDependentContext(); 2263 2264 if (!IsDependentContext && 2265 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2266 return 0; 2267 2268 if (isa<CXXRecordDecl>(DC)) { 2269 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2270 Diag(D.getIdentifierLoc(), 2271 diag::err_member_def_undefined_record) 2272 << Name << DC << D.getCXXScopeSpec().getRange(); 2273 D.setInvalidType(); 2274 } else if (isa<CXXRecordDecl>(CurContext) && 2275 !D.getDeclSpec().isFriendSpecified()) { 2276 // The user provided a superfluous scope specifier inside a class 2277 // definition: 2278 // 2279 // class X { 2280 // void X::f(); 2281 // }; 2282 if (CurContext->Equals(DC)) 2283 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2284 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2285 else 2286 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2287 << Name << D.getCXXScopeSpec().getRange(); 2288 2289 // Pretend that this qualifier was not here. 2290 D.getCXXScopeSpec().clear(); 2291 } 2292 } 2293 2294 // Check whether we need to rebuild the type of the given 2295 // declaration in the current instantiation. 2296 if (EnteringContext && IsDependentContext && 2297 TemplateParamLists.size() != 0) { 2298 ContextRAII SavedContext(*this, DC); 2299 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2300 D.setInvalidType(); 2301 } 2302 } 2303 2304 // C++ [class.mem]p13: 2305 // If T is the name of a class, then each of the following shall have a 2306 // name different from T: 2307 // - every static data member of class T; 2308 // - every member function of class T 2309 // - every member of class T that is itself a type; 2310 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2311 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2312 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2313 << Name; 2314 2315 // If this is a typedef, we'll end up spewing multiple diagnostics. 2316 // Just return early; it's safer. 2317 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2318 return 0; 2319 } 2320 2321 NamedDecl *New; 2322 2323 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2324 QualType R = TInfo->getType(); 2325 2326 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2327 ForRedeclaration); 2328 2329 // See if this is a redefinition of a variable in the same scope. 2330 if (!D.getCXXScopeSpec().isSet()) { 2331 bool IsLinkageLookup = false; 2332 2333 // If the declaration we're planning to build will be a function 2334 // or object with linkage, then look for another declaration with 2335 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2336 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2337 /* Do nothing*/; 2338 else if (R->isFunctionType()) { 2339 if (CurContext->isFunctionOrMethod() || 2340 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2341 IsLinkageLookup = true; 2342 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2343 IsLinkageLookup = true; 2344 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2345 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2346 IsLinkageLookup = true; 2347 2348 if (IsLinkageLookup) 2349 Previous.clear(LookupRedeclarationWithLinkage); 2350 2351 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2352 } else { // Something like "int foo::x;" 2353 LookupQualifiedName(Previous, DC); 2354 2355 // Don't consider using declarations as previous declarations for 2356 // out-of-line members. 2357 RemoveUsingDecls(Previous); 2358 2359 // C++ 7.3.1.2p2: 2360 // Members (including explicit specializations of templates) of a named 2361 // namespace can also be defined outside that namespace by explicit 2362 // qualification of the name being defined, provided that the entity being 2363 // defined was already declared in the namespace and the definition appears 2364 // after the point of declaration in a namespace that encloses the 2365 // declarations namespace. 2366 // 2367 // Note that we only check the context at this point. We don't yet 2368 // have enough information to make sure that PrevDecl is actually 2369 // the declaration we want to match. For example, given: 2370 // 2371 // class X { 2372 // void f(); 2373 // void f(float); 2374 // }; 2375 // 2376 // void X::f(int) { } // ill-formed 2377 // 2378 // In this case, PrevDecl will point to the overload set 2379 // containing the two f's declared in X, but neither of them 2380 // matches. 2381 2382 // First check whether we named the global scope. 2383 if (isa<TranslationUnitDecl>(DC)) { 2384 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2385 << Name << D.getCXXScopeSpec().getRange(); 2386 } else { 2387 DeclContext *Cur = CurContext; 2388 while (isa<LinkageSpecDecl>(Cur)) 2389 Cur = Cur->getParent(); 2390 if (!Cur->Encloses(DC)) { 2391 // The qualifying scope doesn't enclose the original declaration. 2392 // Emit diagnostic based on current scope. 2393 SourceLocation L = D.getIdentifierLoc(); 2394 SourceRange R = D.getCXXScopeSpec().getRange(); 2395 if (isa<FunctionDecl>(Cur)) 2396 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2397 else 2398 Diag(L, diag::err_invalid_declarator_scope) 2399 << Name << cast<NamedDecl>(DC) << R; 2400 D.setInvalidType(); 2401 } 2402 } 2403 } 2404 2405 if (Previous.isSingleResult() && 2406 Previous.getFoundDecl()->isTemplateParameter()) { 2407 // Maybe we will complain about the shadowed template parameter. 2408 if (!D.isInvalidType()) 2409 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2410 Previous.getFoundDecl())) 2411 D.setInvalidType(); 2412 2413 // Just pretend that we didn't see the previous declaration. 2414 Previous.clear(); 2415 } 2416 2417 // In C++, the previous declaration we find might be a tag type 2418 // (class or enum). In this case, the new declaration will hide the 2419 // tag type. Note that this does does not apply if we're declaring a 2420 // typedef (C++ [dcl.typedef]p4). 2421 if (Previous.isSingleTagDecl() && 2422 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2423 Previous.clear(); 2424 2425 bool Redeclaration = false; 2426 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2427 if (TemplateParamLists.size()) { 2428 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2429 return 0; 2430 } 2431 2432 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2433 } else if (R->isFunctionType()) { 2434 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2435 move(TemplateParamLists), 2436 IsFunctionDefinition, Redeclaration); 2437 } else { 2438 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2439 move(TemplateParamLists), 2440 Redeclaration); 2441 } 2442 2443 if (New == 0) 2444 return 0; 2445 2446 // If this has an identifier and is not an invalid redeclaration or 2447 // function template specialization, add it to the scope stack. 2448 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2449 PushOnScopeChains(New, S); 2450 2451 return New; 2452} 2453 2454/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2455/// types into constant array types in certain situations which would otherwise 2456/// be errors (for GCC compatibility). 2457static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2458 ASTContext &Context, 2459 bool &SizeIsNegative, 2460 llvm::APSInt &Oversized) { 2461 // This method tries to turn a variable array into a constant 2462 // array even when the size isn't an ICE. This is necessary 2463 // for compatibility with code that depends on gcc's buggy 2464 // constant expression folding, like struct {char x[(int)(char*)2];} 2465 SizeIsNegative = false; 2466 Oversized = 0; 2467 2468 if (T->isDependentType()) 2469 return QualType(); 2470 2471 QualifierCollector Qs; 2472 const Type *Ty = Qs.strip(T); 2473 2474 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2475 QualType Pointee = PTy->getPointeeType(); 2476 QualType FixedType = 2477 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2478 Oversized); 2479 if (FixedType.isNull()) return FixedType; 2480 FixedType = Context.getPointerType(FixedType); 2481 return Qs.apply(FixedType); 2482 } 2483 2484 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2485 if (!VLATy) 2486 return QualType(); 2487 // FIXME: We should probably handle this case 2488 if (VLATy->getElementType()->isVariablyModifiedType()) 2489 return QualType(); 2490 2491 Expr::EvalResult EvalResult; 2492 if (!VLATy->getSizeExpr() || 2493 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2494 !EvalResult.Val.isInt()) 2495 return QualType(); 2496 2497 // Check whether the array size is negative. 2498 llvm::APSInt &Res = EvalResult.Val.getInt(); 2499 if (Res.isSigned() && Res.isNegative()) { 2500 SizeIsNegative = true; 2501 return QualType(); 2502 } 2503 2504 // Check whether the array is too large to be addressed. 2505 unsigned ActiveSizeBits 2506 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2507 Res); 2508 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2509 Oversized = Res; 2510 return QualType(); 2511 } 2512 2513 return Context.getConstantArrayType(VLATy->getElementType(), 2514 Res, ArrayType::Normal, 0); 2515} 2516 2517/// \brief Register the given locally-scoped external C declaration so 2518/// that it can be found later for redeclarations 2519void 2520Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2521 const LookupResult &Previous, 2522 Scope *S) { 2523 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2524 "Decl is not a locally-scoped decl!"); 2525 // Note that we have a locally-scoped external with this name. 2526 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2527 2528 if (!Previous.isSingleResult()) 2529 return; 2530 2531 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2532 2533 // If there was a previous declaration of this variable, it may be 2534 // in our identifier chain. Update the identifier chain with the new 2535 // declaration. 2536 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2537 // The previous declaration was found on the identifer resolver 2538 // chain, so remove it from its scope. 2539 while (S && !S->isDeclScope(PrevDecl)) 2540 S = S->getParent(); 2541 2542 if (S) 2543 S->RemoveDecl(PrevDecl); 2544 } 2545} 2546 2547/// \brief Diagnose function specifiers on a declaration of an identifier that 2548/// does not identify a function. 2549void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2550 // FIXME: We should probably indicate the identifier in question to avoid 2551 // confusion for constructs like "inline int a(), b;" 2552 if (D.getDeclSpec().isInlineSpecified()) 2553 Diag(D.getDeclSpec().getInlineSpecLoc(), 2554 diag::err_inline_non_function); 2555 2556 if (D.getDeclSpec().isVirtualSpecified()) 2557 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2558 diag::err_virtual_non_function); 2559 2560 if (D.getDeclSpec().isExplicitSpecified()) 2561 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2562 diag::err_explicit_non_function); 2563} 2564 2565NamedDecl* 2566Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2567 QualType R, TypeSourceInfo *TInfo, 2568 LookupResult &Previous, bool &Redeclaration) { 2569 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2570 if (D.getCXXScopeSpec().isSet()) { 2571 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2572 << D.getCXXScopeSpec().getRange(); 2573 D.setInvalidType(); 2574 // Pretend we didn't see the scope specifier. 2575 DC = CurContext; 2576 Previous.clear(); 2577 } 2578 2579 if (getLangOptions().CPlusPlus) { 2580 // Check that there are no default arguments (C++ only). 2581 CheckExtraCXXDefaultArguments(D); 2582 } 2583 2584 DiagnoseFunctionSpecifiers(D); 2585 2586 if (D.getDeclSpec().isThreadSpecified()) 2587 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2588 2589 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2590 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2591 << D.getName().getSourceRange(); 2592 return 0; 2593 } 2594 2595 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2596 if (!NewTD) return 0; 2597 2598 // Handle attributes prior to checking for duplicates in MergeVarDecl 2599 ProcessDeclAttributes(S, NewTD, D); 2600 2601 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2602 // then it shall have block scope. 2603 // Note that variably modified types must be fixed before merging the decl so 2604 // that redeclarations will match. 2605 QualType T = NewTD->getUnderlyingType(); 2606 if (T->isVariablyModifiedType()) { 2607 getCurFunction()->setHasBranchProtectedScope(); 2608 2609 if (S->getFnParent() == 0) { 2610 bool SizeIsNegative; 2611 llvm::APSInt Oversized; 2612 QualType FixedTy = 2613 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2614 Oversized); 2615 if (!FixedTy.isNull()) { 2616 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2617 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2618 } else { 2619 if (SizeIsNegative) 2620 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2621 else if (T->isVariableArrayType()) 2622 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2623 else if (Oversized.getBoolValue()) 2624 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2625 << Oversized.toString(10); 2626 else 2627 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2628 NewTD->setInvalidDecl(); 2629 } 2630 } 2631 } 2632 2633 // Merge the decl with the existing one if appropriate. If the decl is 2634 // in an outer scope, it isn't the same thing. 2635 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2636 if (!Previous.empty()) { 2637 Redeclaration = true; 2638 MergeTypeDefDecl(NewTD, Previous); 2639 } 2640 2641 // If this is the C FILE type, notify the AST context. 2642 if (IdentifierInfo *II = NewTD->getIdentifier()) 2643 if (!NewTD->isInvalidDecl() && 2644 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2645 if (II->isStr("FILE")) 2646 Context.setFILEDecl(NewTD); 2647 else if (II->isStr("jmp_buf")) 2648 Context.setjmp_bufDecl(NewTD); 2649 else if (II->isStr("sigjmp_buf")) 2650 Context.setsigjmp_bufDecl(NewTD); 2651 else if (II->isStr("__builtin_va_list")) 2652 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2653 } 2654 2655 return NewTD; 2656} 2657 2658/// \brief Determines whether the given declaration is an out-of-scope 2659/// previous declaration. 2660/// 2661/// This routine should be invoked when name lookup has found a 2662/// previous declaration (PrevDecl) that is not in the scope where a 2663/// new declaration by the same name is being introduced. If the new 2664/// declaration occurs in a local scope, previous declarations with 2665/// linkage may still be considered previous declarations (C99 2666/// 6.2.2p4-5, C++ [basic.link]p6). 2667/// 2668/// \param PrevDecl the previous declaration found by name 2669/// lookup 2670/// 2671/// \param DC the context in which the new declaration is being 2672/// declared. 2673/// 2674/// \returns true if PrevDecl is an out-of-scope previous declaration 2675/// for a new delcaration with the same name. 2676static bool 2677isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2678 ASTContext &Context) { 2679 if (!PrevDecl) 2680 return false; 2681 2682 if (!PrevDecl->hasLinkage()) 2683 return false; 2684 2685 if (Context.getLangOptions().CPlusPlus) { 2686 // C++ [basic.link]p6: 2687 // If there is a visible declaration of an entity with linkage 2688 // having the same name and type, ignoring entities declared 2689 // outside the innermost enclosing namespace scope, the block 2690 // scope declaration declares that same entity and receives the 2691 // linkage of the previous declaration. 2692 DeclContext *OuterContext = DC->getRedeclContext(); 2693 if (!OuterContext->isFunctionOrMethod()) 2694 // This rule only applies to block-scope declarations. 2695 return false; 2696 2697 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2698 if (PrevOuterContext->isRecord()) 2699 // We found a member function: ignore it. 2700 return false; 2701 2702 // Find the innermost enclosing namespace for the new and 2703 // previous declarations. 2704 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2705 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2706 2707 // The previous declaration is in a different namespace, so it 2708 // isn't the same function. 2709 if (!OuterContext->Equals(PrevOuterContext)) 2710 return false; 2711 } 2712 2713 return true; 2714} 2715 2716static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2717 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2718 if (!SS.isSet()) return; 2719 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2720 SS.getRange()); 2721} 2722 2723NamedDecl* 2724Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 2725 QualType R, TypeSourceInfo *TInfo, 2726 LookupResult &Previous, 2727 MultiTemplateParamsArg TemplateParamLists, 2728 bool &Redeclaration) { 2729 DeclarationName Name = GetNameForDeclarator(D).getName(); 2730 2731 // Check that there are no default arguments (C++ only). 2732 if (getLangOptions().CPlusPlus) 2733 CheckExtraCXXDefaultArguments(D); 2734 2735 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2736 assert(SCSpec != DeclSpec::SCS_typedef && 2737 "Parser allowed 'typedef' as storage class VarDecl."); 2738 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2739 if (SCSpec == DeclSpec::SCS_mutable) { 2740 // mutable can only appear on non-static class members, so it's always 2741 // an error here 2742 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2743 D.setInvalidType(); 2744 SC = SC_None; 2745 } 2746 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2747 VarDecl::StorageClass SCAsWritten 2748 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2749 2750 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2751 if (!II) { 2752 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2753 << Name.getAsString(); 2754 return 0; 2755 } 2756 2757 DiagnoseFunctionSpecifiers(D); 2758 2759 if (!DC->isRecord() && S->getFnParent() == 0) { 2760 // C99 6.9p2: The storage-class specifiers auto and register shall not 2761 // appear in the declaration specifiers in an external declaration. 2762 if (SC == SC_Auto || SC == SC_Register) { 2763 2764 // If this is a register variable with an asm label specified, then this 2765 // is a GNU extension. 2766 if (SC == SC_Register && D.getAsmLabel()) 2767 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2768 else 2769 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2770 D.setInvalidType(); 2771 } 2772 } 2773 if (DC->isRecord() && !CurContext->isRecord()) { 2774 // This is an out-of-line definition of a static data member. 2775 if (SC == SC_Static) { 2776 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2777 diag::err_static_out_of_line) 2778 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2779 } else if (SC == SC_None) 2780 SC = SC_Static; 2781 } 2782 if (SC == SC_Static) { 2783 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2784 if (RD->isLocalClass()) 2785 Diag(D.getIdentifierLoc(), 2786 diag::err_static_data_member_not_allowed_in_local_class) 2787 << Name << RD->getDeclName(); 2788 } 2789 } 2790 2791 // Match up the template parameter lists with the scope specifier, then 2792 // determine whether we have a template or a template specialization. 2793 bool isExplicitSpecialization = false; 2794 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2795 bool Invalid = false; 2796 if (TemplateParameterList *TemplateParams 2797 = MatchTemplateParametersToScopeSpecifier( 2798 D.getDeclSpec().getSourceRange().getBegin(), 2799 D.getCXXScopeSpec(), 2800 (TemplateParameterList**)TemplateParamLists.get(), 2801 TemplateParamLists.size(), 2802 /*never a friend*/ false, 2803 isExplicitSpecialization, 2804 Invalid)) { 2805 // All but one template parameter lists have been matching. 2806 --NumMatchedTemplateParamLists; 2807 2808 if (TemplateParams->size() > 0) { 2809 // There is no such thing as a variable template. 2810 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2811 << II 2812 << SourceRange(TemplateParams->getTemplateLoc(), 2813 TemplateParams->getRAngleLoc()); 2814 return 0; 2815 } else { 2816 // There is an extraneous 'template<>' for this variable. Complain 2817 // about it, but allow the declaration of the variable. 2818 Diag(TemplateParams->getTemplateLoc(), 2819 diag::err_template_variable_noparams) 2820 << II 2821 << SourceRange(TemplateParams->getTemplateLoc(), 2822 TemplateParams->getRAngleLoc()); 2823 2824 isExplicitSpecialization = true; 2825 } 2826 } 2827 2828 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2829 II, R, TInfo, SC, SCAsWritten); 2830 2831 if (D.isInvalidType() || Invalid) 2832 NewVD->setInvalidDecl(); 2833 2834 SetNestedNameSpecifier(NewVD, D); 2835 2836 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2837 NewVD->setTemplateParameterListsInfo(Context, 2838 NumMatchedTemplateParamLists, 2839 (TemplateParameterList**)TemplateParamLists.release()); 2840 } 2841 2842 if (D.getDeclSpec().isThreadSpecified()) { 2843 if (NewVD->hasLocalStorage()) 2844 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2845 else if (!Context.Target.isTLSSupported()) 2846 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2847 else 2848 NewVD->setThreadSpecified(true); 2849 } 2850 2851 // Set the lexical context. If the declarator has a C++ scope specifier, the 2852 // lexical context will be different from the semantic context. 2853 NewVD->setLexicalDeclContext(CurContext); 2854 2855 // Handle attributes prior to checking for duplicates in MergeVarDecl 2856 ProcessDeclAttributes(S, NewVD, D); 2857 2858 // Handle GNU asm-label extension (encoded as an attribute). 2859 if (Expr *E = (Expr*)D.getAsmLabel()) { 2860 // The parser guarantees this is a string. 2861 StringLiteral *SE = cast<StringLiteral>(E); 2862 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2863 Context, SE->getString())); 2864 } 2865 2866 // Diagnose shadowed variables before filtering for scope. 2867 if (!D.getCXXScopeSpec().isSet()) 2868 CheckShadow(S, NewVD, Previous); 2869 2870 // Don't consider existing declarations that are in a different 2871 // scope and are out-of-semantic-context declarations (if the new 2872 // declaration has linkage). 2873 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2874 2875 // Merge the decl with the existing one if appropriate. 2876 if (!Previous.empty()) { 2877 if (Previous.isSingleResult() && 2878 isa<FieldDecl>(Previous.getFoundDecl()) && 2879 D.getCXXScopeSpec().isSet()) { 2880 // The user tried to define a non-static data member 2881 // out-of-line (C++ [dcl.meaning]p1). 2882 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2883 << D.getCXXScopeSpec().getRange(); 2884 Previous.clear(); 2885 NewVD->setInvalidDecl(); 2886 } 2887 } else if (D.getCXXScopeSpec().isSet()) { 2888 // No previous declaration in the qualifying scope. 2889 Diag(D.getIdentifierLoc(), diag::err_no_member) 2890 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2891 << D.getCXXScopeSpec().getRange(); 2892 NewVD->setInvalidDecl(); 2893 } 2894 2895 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2896 2897 // This is an explicit specialization of a static data member. Check it. 2898 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2899 CheckMemberSpecialization(NewVD, Previous)) 2900 NewVD->setInvalidDecl(); 2901 2902 // attributes declared post-definition are currently ignored 2903 // FIXME: This should be handled in attribute merging, not 2904 // here. 2905 if (Previous.isSingleResult()) { 2906 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2907 if (Def && (Def = Def->getDefinition()) && 2908 Def != NewVD && D.hasAttributes()) { 2909 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2910 Diag(Def->getLocation(), diag::note_previous_definition); 2911 } 2912 } 2913 2914 // If this is a locally-scoped extern C variable, update the map of 2915 // such variables. 2916 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2917 !NewVD->isInvalidDecl()) 2918 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2919 2920 // If there's a #pragma GCC visibility in scope, and this isn't a class 2921 // member, set the visibility of this variable. 2922 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2923 AddPushedVisibilityAttribute(NewVD); 2924 2925 MarkUnusedFileScopedDecl(NewVD); 2926 2927 return NewVD; 2928} 2929 2930/// \brief Diagnose variable or built-in function shadowing. Implements 2931/// -Wshadow. 2932/// 2933/// This method is called whenever a VarDecl is added to a "useful" 2934/// scope. 2935/// 2936/// \param S the scope in which the shadowing name is being declared 2937/// \param R the lookup of the name 2938/// 2939void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2940 // Return if warning is ignored. 2941 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2942 return; 2943 2944 // Don't diagnose declarations at file scope. The scope might not 2945 // have a DeclContext if (e.g.) we're parsing a function prototype. 2946 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2947 if (NewDC && NewDC->isFileContext()) 2948 return; 2949 2950 // Only diagnose if we're shadowing an unambiguous field or variable. 2951 if (R.getResultKind() != LookupResult::Found) 2952 return; 2953 2954 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2955 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2956 return; 2957 2958 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2959 2960 // Only warn about certain kinds of shadowing for class members. 2961 if (NewDC && NewDC->isRecord()) { 2962 // In particular, don't warn about shadowing non-class members. 2963 if (!OldDC->isRecord()) 2964 return; 2965 2966 // TODO: should we warn about static data members shadowing 2967 // static data members from base classes? 2968 2969 // TODO: don't diagnose for inaccessible shadowed members. 2970 // This is hard to do perfectly because we might friend the 2971 // shadowing context, but that's just a false negative. 2972 } 2973 2974 // Determine what kind of declaration we're shadowing. 2975 unsigned Kind; 2976 if (isa<RecordDecl>(OldDC)) { 2977 if (isa<FieldDecl>(ShadowedDecl)) 2978 Kind = 3; // field 2979 else 2980 Kind = 2; // static data member 2981 } else if (OldDC->isFileContext()) 2982 Kind = 1; // global 2983 else 2984 Kind = 0; // local 2985 2986 DeclarationName Name = R.getLookupName(); 2987 2988 // Emit warning and note. 2989 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2990 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2991} 2992 2993/// \brief Check -Wshadow without the advantage of a previous lookup. 2994void Sema::CheckShadow(Scope *S, VarDecl *D) { 2995 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2996 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2997 LookupName(R, S); 2998 CheckShadow(S, D, R); 2999} 3000 3001/// \brief Perform semantic checking on a newly-created variable 3002/// declaration. 3003/// 3004/// This routine performs all of the type-checking required for a 3005/// variable declaration once it has been built. It is used both to 3006/// check variables after they have been parsed and their declarators 3007/// have been translated into a declaration, and to check variables 3008/// that have been instantiated from a template. 3009/// 3010/// Sets NewVD->isInvalidDecl() if an error was encountered. 3011void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3012 LookupResult &Previous, 3013 bool &Redeclaration) { 3014 // If the decl is already known invalid, don't check it. 3015 if (NewVD->isInvalidDecl()) 3016 return; 3017 3018 QualType T = NewVD->getType(); 3019 3020 if (T->isObjCObjectType()) { 3021 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3022 return NewVD->setInvalidDecl(); 3023 } 3024 3025 // Emit an error if an address space was applied to decl with local storage. 3026 // This includes arrays of objects with address space qualifiers, but not 3027 // automatic variables that point to other address spaces. 3028 // ISO/IEC TR 18037 S5.1.2 3029 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3030 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3031 return NewVD->setInvalidDecl(); 3032 } 3033 3034 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3035 && !NewVD->hasAttr<BlocksAttr>()) 3036 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3037 3038 bool isVM = T->isVariablyModifiedType(); 3039 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3040 NewVD->hasAttr<BlocksAttr>()) 3041 getCurFunction()->setHasBranchProtectedScope(); 3042 3043 if ((isVM && NewVD->hasLinkage()) || 3044 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3045 bool SizeIsNegative; 3046 llvm::APSInt Oversized; 3047 QualType FixedTy = 3048 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3049 Oversized); 3050 3051 if (FixedTy.isNull() && T->isVariableArrayType()) { 3052 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3053 // FIXME: This won't give the correct result for 3054 // int a[10][n]; 3055 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3056 3057 if (NewVD->isFileVarDecl()) 3058 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3059 << SizeRange; 3060 else if (NewVD->getStorageClass() == SC_Static) 3061 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3062 << SizeRange; 3063 else 3064 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3065 << SizeRange; 3066 return NewVD->setInvalidDecl(); 3067 } 3068 3069 if (FixedTy.isNull()) { 3070 if (NewVD->isFileVarDecl()) 3071 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3072 else 3073 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3074 return NewVD->setInvalidDecl(); 3075 } 3076 3077 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3078 NewVD->setType(FixedTy); 3079 } 3080 3081 if (Previous.empty() && NewVD->isExternC()) { 3082 // Since we did not find anything by this name and we're declaring 3083 // an extern "C" variable, look for a non-visible extern "C" 3084 // declaration with the same name. 3085 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3086 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3087 if (Pos != LocallyScopedExternalDecls.end()) 3088 Previous.addDecl(Pos->second); 3089 } 3090 3091 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3092 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3093 << T; 3094 return NewVD->setInvalidDecl(); 3095 } 3096 3097 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3098 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3099 return NewVD->setInvalidDecl(); 3100 } 3101 3102 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3103 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3104 return NewVD->setInvalidDecl(); 3105 } 3106 3107 // Function pointers and references cannot have qualified function type, only 3108 // function pointer-to-members can do that. 3109 QualType Pointee; 3110 unsigned PtrOrRef = 0; 3111 if (const PointerType *Ptr = T->getAs<PointerType>()) 3112 Pointee = Ptr->getPointeeType(); 3113 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3114 Pointee = Ref->getPointeeType(); 3115 PtrOrRef = 1; 3116 } 3117 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3118 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3119 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3120 << PtrOrRef; 3121 return NewVD->setInvalidDecl(); 3122 } 3123 3124 if (!Previous.empty()) { 3125 Redeclaration = true; 3126 MergeVarDecl(NewVD, Previous); 3127 } 3128} 3129 3130/// \brief Data used with FindOverriddenMethod 3131struct FindOverriddenMethodData { 3132 Sema *S; 3133 CXXMethodDecl *Method; 3134}; 3135 3136/// \brief Member lookup function that determines whether a given C++ 3137/// method overrides a method in a base class, to be used with 3138/// CXXRecordDecl::lookupInBases(). 3139static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3140 CXXBasePath &Path, 3141 void *UserData) { 3142 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3143 3144 FindOverriddenMethodData *Data 3145 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3146 3147 DeclarationName Name = Data->Method->getDeclName(); 3148 3149 // FIXME: Do we care about other names here too? 3150 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3151 // We really want to find the base class destructor here. 3152 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3153 CanQualType CT = Data->S->Context.getCanonicalType(T); 3154 3155 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3156 } 3157 3158 for (Path.Decls = BaseRecord->lookup(Name); 3159 Path.Decls.first != Path.Decls.second; 3160 ++Path.Decls.first) { 3161 NamedDecl *D = *Path.Decls.first; 3162 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3163 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3164 return true; 3165 } 3166 } 3167 3168 return false; 3169} 3170 3171/// AddOverriddenMethods - See if a method overrides any in the base classes, 3172/// and if so, check that it's a valid override and remember it. 3173bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3174 // Look for virtual methods in base classes that this method might override. 3175 CXXBasePaths Paths; 3176 FindOverriddenMethodData Data; 3177 Data.Method = MD; 3178 Data.S = this; 3179 bool AddedAny = false; 3180 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3181 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3182 E = Paths.found_decls_end(); I != E; ++I) { 3183 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3184 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3185 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3186 !CheckOverridingFunctionAttributes(MD, OldMD)) { 3187 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3188 AddedAny = true; 3189 } 3190 } 3191 } 3192 } 3193 3194 return AddedAny; 3195} 3196 3197static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3198 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3199 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3200 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3201 assert(!Prev.isAmbiguous() && 3202 "Cannot have an ambiguity in previous-declaration lookup"); 3203 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3204 Func != FuncEnd; ++Func) { 3205 if (isa<FunctionDecl>(*Func) && 3206 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3207 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3208 } 3209} 3210 3211NamedDecl* 3212Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3213 QualType R, TypeSourceInfo *TInfo, 3214 LookupResult &Previous, 3215 MultiTemplateParamsArg TemplateParamLists, 3216 bool IsFunctionDefinition, bool &Redeclaration) { 3217 assert(R.getTypePtr()->isFunctionType()); 3218 3219 // TODO: consider using NameInfo for diagnostic. 3220 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3221 DeclarationName Name = NameInfo.getName(); 3222 FunctionDecl::StorageClass SC = SC_None; 3223 switch (D.getDeclSpec().getStorageClassSpec()) { 3224 default: assert(0 && "Unknown storage class!"); 3225 case DeclSpec::SCS_auto: 3226 case DeclSpec::SCS_register: 3227 case DeclSpec::SCS_mutable: 3228 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3229 diag::err_typecheck_sclass_func); 3230 D.setInvalidType(); 3231 break; 3232 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3233 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3234 case DeclSpec::SCS_static: { 3235 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3236 // C99 6.7.1p5: 3237 // The declaration of an identifier for a function that has 3238 // block scope shall have no explicit storage-class specifier 3239 // other than extern 3240 // See also (C++ [dcl.stc]p4). 3241 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3242 diag::err_static_block_func); 3243 SC = SC_None; 3244 } else 3245 SC = SC_Static; 3246 break; 3247 } 3248 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3249 } 3250 3251 if (D.getDeclSpec().isThreadSpecified()) 3252 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3253 3254 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3255 bool isInline = D.getDeclSpec().isInlineSpecified(); 3256 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3257 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3258 3259 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3260 FunctionDecl::StorageClass SCAsWritten 3261 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3262 3263 // Check that the return type is not an abstract class type. 3264 // For record types, this is done by the AbstractClassUsageDiagnoser once 3265 // the class has been completely parsed. 3266 if (!DC->isRecord() && 3267 RequireNonAbstractType(D.getIdentifierLoc(), 3268 R->getAs<FunctionType>()->getResultType(), 3269 diag::err_abstract_type_in_decl, 3270 AbstractReturnType)) 3271 D.setInvalidType(); 3272 3273 // Do not allow returning a objc interface by-value. 3274 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3275 Diag(D.getIdentifierLoc(), 3276 diag::err_object_cannot_be_passed_returned_by_value) << 0 3277 << R->getAs<FunctionType>()->getResultType(); 3278 D.setInvalidType(); 3279 } 3280 3281 bool isVirtualOkay = false; 3282 FunctionDecl *NewFD; 3283 3284 if (isFriend) { 3285 // C++ [class.friend]p5 3286 // A function can be defined in a friend declaration of a 3287 // class . . . . Such a function is implicitly inline. 3288 isInline |= IsFunctionDefinition; 3289 } 3290 3291 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3292 // This is a C++ constructor declaration. 3293 assert(DC->isRecord() && 3294 "Constructors can only be declared in a member context"); 3295 3296 R = CheckConstructorDeclarator(D, R, SC); 3297 3298 // Create the new declaration 3299 NewFD = CXXConstructorDecl::Create(Context, 3300 cast<CXXRecordDecl>(DC), 3301 NameInfo, R, TInfo, 3302 isExplicit, isInline, 3303 /*isImplicitlyDeclared=*/false); 3304 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3305 // This is a C++ destructor declaration. 3306 if (DC->isRecord()) { 3307 R = CheckDestructorDeclarator(D, R, SC); 3308 3309 NewFD = CXXDestructorDecl::Create(Context, 3310 cast<CXXRecordDecl>(DC), 3311 NameInfo, R, 3312 isInline, 3313 /*isImplicitlyDeclared=*/false); 3314 NewFD->setTypeSourceInfo(TInfo); 3315 3316 isVirtualOkay = true; 3317 } else { 3318 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3319 3320 // Create a FunctionDecl to satisfy the function definition parsing 3321 // code path. 3322 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3323 Name, R, TInfo, SC, SCAsWritten, isInline, 3324 /*hasPrototype=*/true); 3325 D.setInvalidType(); 3326 } 3327 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3328 if (!DC->isRecord()) { 3329 Diag(D.getIdentifierLoc(), 3330 diag::err_conv_function_not_member); 3331 return 0; 3332 } 3333 3334 CheckConversionDeclarator(D, R, SC); 3335 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3336 NameInfo, R, TInfo, 3337 isInline, isExplicit); 3338 3339 isVirtualOkay = true; 3340 } else if (DC->isRecord()) { 3341 // If the of the function is the same as the name of the record, then this 3342 // must be an invalid constructor that has a return type. 3343 // (The parser checks for a return type and makes the declarator a 3344 // constructor if it has no return type). 3345 // must have an invalid constructor that has a return type 3346 if (Name.getAsIdentifierInfo() && 3347 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3348 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3349 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3350 << SourceRange(D.getIdentifierLoc()); 3351 return 0; 3352 } 3353 3354 bool isStatic = SC == SC_Static; 3355 3356 // [class.free]p1: 3357 // Any allocation function for a class T is a static member 3358 // (even if not explicitly declared static). 3359 if (Name.getCXXOverloadedOperator() == OO_New || 3360 Name.getCXXOverloadedOperator() == OO_Array_New) 3361 isStatic = true; 3362 3363 // [class.free]p6 Any deallocation function for a class X is a static member 3364 // (even if not explicitly declared static). 3365 if (Name.getCXXOverloadedOperator() == OO_Delete || 3366 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3367 isStatic = true; 3368 3369 // This is a C++ method declaration. 3370 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3371 NameInfo, R, TInfo, 3372 isStatic, SCAsWritten, isInline); 3373 3374 isVirtualOkay = !isStatic; 3375 } else { 3376 // Determine whether the function was written with a 3377 // prototype. This true when: 3378 // - we're in C++ (where every function has a prototype), 3379 // - there is a prototype in the declarator, or 3380 // - the type R of the function is some kind of typedef or other reference 3381 // to a type name (which eventually refers to a function type). 3382 bool HasPrototype = 3383 getLangOptions().CPlusPlus || 3384 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3385 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3386 3387 NewFD = FunctionDecl::Create(Context, DC, 3388 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3389 HasPrototype); 3390 } 3391 3392 if (D.isInvalidType()) 3393 NewFD->setInvalidDecl(); 3394 3395 SetNestedNameSpecifier(NewFD, D); 3396 3397 // Set the lexical context. If the declarator has a C++ 3398 // scope specifier, or is the object of a friend declaration, the 3399 // lexical context will be different from the semantic context. 3400 NewFD->setLexicalDeclContext(CurContext); 3401 3402 // Match up the template parameter lists with the scope specifier, then 3403 // determine whether we have a template or a template specialization. 3404 FunctionTemplateDecl *FunctionTemplate = 0; 3405 bool isExplicitSpecialization = false; 3406 bool isFunctionTemplateSpecialization = false; 3407 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3408 bool Invalid = false; 3409 if (TemplateParameterList *TemplateParams 3410 = MatchTemplateParametersToScopeSpecifier( 3411 D.getDeclSpec().getSourceRange().getBegin(), 3412 D.getCXXScopeSpec(), 3413 (TemplateParameterList**)TemplateParamLists.get(), 3414 TemplateParamLists.size(), 3415 isFriend, 3416 isExplicitSpecialization, 3417 Invalid)) { 3418 // All but one template parameter lists have been matching. 3419 --NumMatchedTemplateParamLists; 3420 3421 if (TemplateParams->size() > 0) { 3422 // This is a function template 3423 3424 // Check that we can declare a template here. 3425 if (CheckTemplateDeclScope(S, TemplateParams)) 3426 return 0; 3427 3428 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3429 NewFD->getLocation(), 3430 Name, TemplateParams, 3431 NewFD); 3432 FunctionTemplate->setLexicalDeclContext(CurContext); 3433 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3434 } else { 3435 // This is a function template specialization. 3436 isFunctionTemplateSpecialization = true; 3437 3438 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3439 if (isFriend && isFunctionTemplateSpecialization) { 3440 // We want to remove the "template<>", found here. 3441 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3442 3443 // If we remove the template<> and the name is not a 3444 // template-id, we're actually silently creating a problem: 3445 // the friend declaration will refer to an untemplated decl, 3446 // and clearly the user wants a template specialization. So 3447 // we need to insert '<>' after the name. 3448 SourceLocation InsertLoc; 3449 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3450 InsertLoc = D.getName().getSourceRange().getEnd(); 3451 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3452 } 3453 3454 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3455 << Name << RemoveRange 3456 << FixItHint::CreateRemoval(RemoveRange) 3457 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3458 } 3459 } 3460 } 3461 3462 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3463 NewFD->setTemplateParameterListsInfo(Context, 3464 NumMatchedTemplateParamLists, 3465 (TemplateParameterList**)TemplateParamLists.release()); 3466 } 3467 3468 if (Invalid) { 3469 NewFD->setInvalidDecl(); 3470 if (FunctionTemplate) 3471 FunctionTemplate->setInvalidDecl(); 3472 } 3473 3474 // C++ [dcl.fct.spec]p5: 3475 // The virtual specifier shall only be used in declarations of 3476 // nonstatic class member functions that appear within a 3477 // member-specification of a class declaration; see 10.3. 3478 // 3479 if (isVirtual && !NewFD->isInvalidDecl()) { 3480 if (!isVirtualOkay) { 3481 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3482 diag::err_virtual_non_function); 3483 } else if (!CurContext->isRecord()) { 3484 // 'virtual' was specified outside of the class. 3485 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3486 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3487 } else { 3488 // Okay: Add virtual to the method. 3489 NewFD->setVirtualAsWritten(true); 3490 } 3491 } 3492 3493 // C++ [dcl.fct.spec]p3: 3494 // The inline specifier shall not appear on a block scope function declaration. 3495 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3496 if (CurContext->isFunctionOrMethod()) { 3497 // 'inline' is not allowed on block scope function declaration. 3498 Diag(D.getDeclSpec().getInlineSpecLoc(), 3499 diag::err_inline_declaration_block_scope) << Name 3500 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3501 } 3502 } 3503 3504 // C++ [dcl.fct.spec]p6: 3505 // The explicit specifier shall be used only in the declaration of a 3506 // constructor or conversion function within its class definition; see 12.3.1 3507 // and 12.3.2. 3508 if (isExplicit && !NewFD->isInvalidDecl()) { 3509 if (!CurContext->isRecord()) { 3510 // 'explicit' was specified outside of the class. 3511 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3512 diag::err_explicit_out_of_class) 3513 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3514 } else if (!isa<CXXConstructorDecl>(NewFD) && 3515 !isa<CXXConversionDecl>(NewFD)) { 3516 // 'explicit' was specified on a function that wasn't a constructor 3517 // or conversion function. 3518 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3519 diag::err_explicit_non_ctor_or_conv_function) 3520 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3521 } 3522 } 3523 3524 // Filter out previous declarations that don't match the scope. 3525 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3526 3527 if (isFriend) { 3528 // For now, claim that the objects have no previous declaration. 3529 if (FunctionTemplate) { 3530 FunctionTemplate->setObjectOfFriendDecl(false); 3531 FunctionTemplate->setAccess(AS_public); 3532 } 3533 NewFD->setObjectOfFriendDecl(false); 3534 NewFD->setAccess(AS_public); 3535 } 3536 3537 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3538 !CurContext->isRecord()) { 3539 // C++ [class.static]p1: 3540 // A data or function member of a class may be declared static 3541 // in a class definition, in which case it is a static member of 3542 // the class. 3543 3544 // Complain about the 'static' specifier if it's on an out-of-line 3545 // member function definition. 3546 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3547 diag::err_static_out_of_line) 3548 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3549 } 3550 3551 // Handle GNU asm-label extension (encoded as an attribute). 3552 if (Expr *E = (Expr*) D.getAsmLabel()) { 3553 // The parser guarantees this is a string. 3554 StringLiteral *SE = cast<StringLiteral>(E); 3555 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3556 SE->getString())); 3557 } 3558 3559 // Copy the parameter declarations from the declarator D to the function 3560 // declaration NewFD, if they are available. First scavenge them into Params. 3561 llvm::SmallVector<ParmVarDecl*, 16> Params; 3562 if (D.getNumTypeObjects() > 0) { 3563 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3564 3565 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3566 // function that takes no arguments, not a function that takes a 3567 // single void argument. 3568 // We let through "const void" here because Sema::GetTypeForDeclarator 3569 // already checks for that case. 3570 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3571 FTI.ArgInfo[0].Param && 3572 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3573 // Empty arg list, don't push any params. 3574 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3575 3576 // In C++, the empty parameter-type-list must be spelled "void"; a 3577 // typedef of void is not permitted. 3578 if (getLangOptions().CPlusPlus && 3579 Param->getType().getUnqualifiedType() != Context.VoidTy) 3580 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3581 // FIXME: Leaks decl? 3582 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3583 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3584 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3585 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3586 Param->setDeclContext(NewFD); 3587 Params.push_back(Param); 3588 3589 if (Param->isInvalidDecl()) 3590 NewFD->setInvalidDecl(); 3591 } 3592 } 3593 3594 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3595 // When we're declaring a function with a typedef, typeof, etc as in the 3596 // following example, we'll need to synthesize (unnamed) 3597 // parameters for use in the declaration. 3598 // 3599 // @code 3600 // typedef void fn(int); 3601 // fn f; 3602 // @endcode 3603 3604 // Synthesize a parameter for each argument type. 3605 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3606 AE = FT->arg_type_end(); AI != AE; ++AI) { 3607 ParmVarDecl *Param = 3608 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3609 Params.push_back(Param); 3610 } 3611 } else { 3612 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3613 "Should not need args for typedef of non-prototype fn"); 3614 } 3615 // Finally, we know we have the right number of parameters, install them. 3616 NewFD->setParams(Params.data(), Params.size()); 3617 3618 // If the declarator is a template-id, translate the parser's template 3619 // argument list into our AST format. 3620 bool HasExplicitTemplateArgs = false; 3621 TemplateArgumentListInfo TemplateArgs; 3622 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3623 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3624 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3625 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3626 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3627 TemplateId->getTemplateArgs(), 3628 TemplateId->NumArgs); 3629 translateTemplateArguments(TemplateArgsPtr, 3630 TemplateArgs); 3631 TemplateArgsPtr.release(); 3632 3633 HasExplicitTemplateArgs = true; 3634 3635 if (FunctionTemplate) { 3636 // FIXME: Diagnose function template with explicit template 3637 // arguments. 3638 HasExplicitTemplateArgs = false; 3639 } else if (!isFunctionTemplateSpecialization && 3640 !D.getDeclSpec().isFriendSpecified()) { 3641 // We have encountered something that the user meant to be a 3642 // specialization (because it has explicitly-specified template 3643 // arguments) but that was not introduced with a "template<>" (or had 3644 // too few of them). 3645 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3646 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3647 << FixItHint::CreateInsertion( 3648 D.getDeclSpec().getSourceRange().getBegin(), 3649 "template<> "); 3650 isFunctionTemplateSpecialization = true; 3651 } else { 3652 // "friend void foo<>(int);" is an implicit specialization decl. 3653 isFunctionTemplateSpecialization = true; 3654 } 3655 } else if (isFriend && isFunctionTemplateSpecialization) { 3656 // This combination is only possible in a recovery case; the user 3657 // wrote something like: 3658 // template <> friend void foo(int); 3659 // which we're recovering from as if the user had written: 3660 // friend void foo<>(int); 3661 // Go ahead and fake up a template id. 3662 HasExplicitTemplateArgs = true; 3663 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3664 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3665 } 3666 3667 // If it's a friend (and only if it's a friend), it's possible 3668 // that either the specialized function type or the specialized 3669 // template is dependent, and therefore matching will fail. In 3670 // this case, don't check the specialization yet. 3671 if (isFunctionTemplateSpecialization && isFriend && 3672 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3673 assert(HasExplicitTemplateArgs && 3674 "friend function specialization without template args"); 3675 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3676 Previous)) 3677 NewFD->setInvalidDecl(); 3678 } else if (isFunctionTemplateSpecialization) { 3679 if (CheckFunctionTemplateSpecialization(NewFD, 3680 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3681 Previous)) 3682 NewFD->setInvalidDecl(); 3683 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3684 if (CheckMemberSpecialization(NewFD, Previous)) 3685 NewFD->setInvalidDecl(); 3686 } 3687 3688 // Perform semantic checking on the function declaration. 3689 bool OverloadableAttrRequired = false; // FIXME: HACK! 3690 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3691 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3692 3693 assert((NewFD->isInvalidDecl() || !Redeclaration || 3694 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3695 "previous declaration set still overloaded"); 3696 3697 NamedDecl *PrincipalDecl = (FunctionTemplate 3698 ? cast<NamedDecl>(FunctionTemplate) 3699 : NewFD); 3700 3701 if (isFriend && Redeclaration) { 3702 AccessSpecifier Access = AS_public; 3703 if (!NewFD->isInvalidDecl()) 3704 Access = NewFD->getPreviousDeclaration()->getAccess(); 3705 3706 NewFD->setAccess(Access); 3707 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3708 3709 PrincipalDecl->setObjectOfFriendDecl(true); 3710 } 3711 3712 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3713 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3714 PrincipalDecl->setNonMemberOperator(); 3715 3716 // If we have a function template, check the template parameter 3717 // list. This will check and merge default template arguments. 3718 if (FunctionTemplate) { 3719 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3720 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3721 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3722 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3723 : TPC_FunctionTemplate); 3724 } 3725 3726 if (NewFD->isInvalidDecl()) { 3727 // Ignore all the rest of this. 3728 } else if (!Redeclaration) { 3729 // Fake up an access specifier if it's supposed to be a class member. 3730 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 3731 NewFD->setAccess(AS_public); 3732 3733 // Qualified decls generally require a previous declaration. 3734 if (D.getCXXScopeSpec().isSet()) { 3735 // ...with the major exception of dependent friend declarations. 3736 // In theory, this condition could be whether the qualifier 3737 // is dependent; in practice, the way we nest template parameters 3738 // prevents this sort of matching from working, so we have to base it 3739 // on the general dependence of the context. 3740 if (isFriend && CurContext->isDependentContext()) { 3741 // ignore these 3742 3743 } else { 3744 // The user tried to provide an out-of-line definition for a 3745 // function that is a member of a class or namespace, but there 3746 // was no such member function declared (C++ [class.mfct]p2, 3747 // C++ [namespace.memdef]p2). For example: 3748 // 3749 // class X { 3750 // void f() const; 3751 // }; 3752 // 3753 // void X::f() { } // ill-formed 3754 // 3755 // Complain about this problem, and attempt to suggest close 3756 // matches (e.g., those that differ only in cv-qualifiers and 3757 // whether the parameter types are references). 3758 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3759 << Name << DC << D.getCXXScopeSpec().getRange(); 3760 NewFD->setInvalidDecl(); 3761 3762 DiagnoseInvalidRedeclaration(*this, NewFD); 3763 } 3764 3765 // Unqualified local friend declarations are required to resolve 3766 // to something. 3767 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 3768 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 3769 NewFD->setInvalidDecl(); 3770 DiagnoseInvalidRedeclaration(*this, NewFD); 3771 } 3772 3773 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 3774 !isFriend && !isFunctionTemplateSpecialization && 3775 !isExplicitSpecialization) { 3776 // An out-of-line member function declaration must also be a 3777 // definition (C++ [dcl.meaning]p1). 3778 // Note that this is not the case for explicit specializations of 3779 // function templates or member functions of class templates, per 3780 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3781 // for compatibility with old SWIG code which likes to generate them. 3782 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3783 << D.getCXXScopeSpec().getRange(); 3784 } 3785 3786 // Handle attributes. We need to have merged decls when handling attributes 3787 // (for example to check for conflicts, etc). 3788 // FIXME: This needs to happen before we merge declarations. Then, 3789 // let attribute merging cope with attribute conflicts. 3790 ProcessDeclAttributes(S, NewFD, D); 3791 3792 // attributes declared post-definition are currently ignored 3793 // FIXME: This should happen during attribute merging 3794 if (Redeclaration && Previous.isSingleResult()) { 3795 const FunctionDecl *Def; 3796 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3797 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3798 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3799 Diag(Def->getLocation(), diag::note_previous_definition); 3800 } 3801 } 3802 3803 AddKnownFunctionAttributes(NewFD); 3804 3805 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3806 // If a function name is overloadable in C, then every function 3807 // with that name must be marked "overloadable". 3808 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3809 << Redeclaration << NewFD; 3810 if (!Previous.empty()) 3811 Diag(Previous.getRepresentativeDecl()->getLocation(), 3812 diag::note_attribute_overloadable_prev_overload); 3813 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3814 } 3815 3816 if (NewFD->hasAttr<OverloadableAttr>() && 3817 !NewFD->getType()->getAs<FunctionProtoType>()) { 3818 Diag(NewFD->getLocation(), 3819 diag::err_attribute_overloadable_no_prototype) 3820 << NewFD; 3821 3822 // Turn this into a variadic function with no parameters. 3823 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3824 QualType R = Context.getFunctionType(FT->getResultType(), 3825 0, 0, true, 0, false, false, 0, 0, 3826 FT->getExtInfo()); 3827 NewFD->setType(R); 3828 } 3829 3830 // If there's a #pragma GCC visibility in scope, and this isn't a class 3831 // member, set the visibility of this function. 3832 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3833 AddPushedVisibilityAttribute(NewFD); 3834 3835 // If this is a locally-scoped extern C function, update the 3836 // map of such names. 3837 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3838 && !NewFD->isInvalidDecl()) 3839 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3840 3841 // Set this FunctionDecl's range up to the right paren. 3842 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3843 3844 if (FunctionTemplate && NewFD->isInvalidDecl()) 3845 FunctionTemplate->setInvalidDecl(); 3846 3847 if (FunctionTemplate) 3848 return FunctionTemplate; 3849 3850 MarkUnusedFileScopedDecl(NewFD); 3851 3852 return NewFD; 3853} 3854 3855/// \brief Perform semantic checking of a new function declaration. 3856/// 3857/// Performs semantic analysis of the new function declaration 3858/// NewFD. This routine performs all semantic checking that does not 3859/// require the actual declarator involved in the declaration, and is 3860/// used both for the declaration of functions as they are parsed 3861/// (called via ActOnDeclarator) and for the declaration of functions 3862/// that have been instantiated via C++ template instantiation (called 3863/// via InstantiateDecl). 3864/// 3865/// \param IsExplicitSpecialiation whether this new function declaration is 3866/// an explicit specialization of the previous declaration. 3867/// 3868/// This sets NewFD->isInvalidDecl() to true if there was an error. 3869void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3870 LookupResult &Previous, 3871 bool IsExplicitSpecialization, 3872 bool &Redeclaration, 3873 bool &OverloadableAttrRequired) { 3874 // If NewFD is already known erroneous, don't do any of this checking. 3875 if (NewFD->isInvalidDecl()) { 3876 // If this is a class member, mark the class invalid immediately. 3877 // This avoids some consistency errors later. 3878 if (isa<CXXMethodDecl>(NewFD)) 3879 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3880 3881 return; 3882 } 3883 3884 if (NewFD->getResultType()->isVariablyModifiedType()) { 3885 // Functions returning a variably modified type violate C99 6.7.5.2p2 3886 // because all functions have linkage. 3887 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3888 return NewFD->setInvalidDecl(); 3889 } 3890 3891 if (NewFD->isMain()) 3892 CheckMain(NewFD); 3893 3894 // Check for a previous declaration of this name. 3895 if (Previous.empty() && NewFD->isExternC()) { 3896 // Since we did not find anything by this name and we're declaring 3897 // an extern "C" function, look for a non-visible extern "C" 3898 // declaration with the same name. 3899 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3900 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3901 if (Pos != LocallyScopedExternalDecls.end()) 3902 Previous.addDecl(Pos->second); 3903 } 3904 3905 // Merge or overload the declaration with an existing declaration of 3906 // the same name, if appropriate. 3907 if (!Previous.empty()) { 3908 // Determine whether NewFD is an overload of PrevDecl or 3909 // a declaration that requires merging. If it's an overload, 3910 // there's no more work to do here; we'll just add the new 3911 // function to the scope. 3912 3913 NamedDecl *OldDecl = 0; 3914 if (!AllowOverloadingOfFunction(Previous, Context)) { 3915 Redeclaration = true; 3916 OldDecl = Previous.getFoundDecl(); 3917 } else { 3918 if (!getLangOptions().CPlusPlus) 3919 OverloadableAttrRequired = true; 3920 3921 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3922 /*NewIsUsingDecl*/ false)) { 3923 case Ovl_Match: 3924 Redeclaration = true; 3925 break; 3926 3927 case Ovl_NonFunction: 3928 Redeclaration = true; 3929 break; 3930 3931 case Ovl_Overload: 3932 Redeclaration = false; 3933 break; 3934 } 3935 } 3936 3937 if (Redeclaration) { 3938 // NewFD and OldDecl represent declarations that need to be 3939 // merged. 3940 if (MergeFunctionDecl(NewFD, OldDecl)) 3941 return NewFD->setInvalidDecl(); 3942 3943 Previous.clear(); 3944 Previous.addDecl(OldDecl); 3945 3946 if (FunctionTemplateDecl *OldTemplateDecl 3947 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3948 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3949 FunctionTemplateDecl *NewTemplateDecl 3950 = NewFD->getDescribedFunctionTemplate(); 3951 assert(NewTemplateDecl && "Template/non-template mismatch"); 3952 if (CXXMethodDecl *Method 3953 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3954 Method->setAccess(OldTemplateDecl->getAccess()); 3955 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3956 } 3957 3958 // If this is an explicit specialization of a member that is a function 3959 // template, mark it as a member specialization. 3960 if (IsExplicitSpecialization && 3961 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3962 NewTemplateDecl->setMemberSpecialization(); 3963 assert(OldTemplateDecl->isMemberSpecialization()); 3964 } 3965 } else { 3966 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3967 NewFD->setAccess(OldDecl->getAccess()); 3968 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3969 } 3970 } 3971 } 3972 3973 // Semantic checking for this function declaration (in isolation). 3974 if (getLangOptions().CPlusPlus) { 3975 // C++-specific checks. 3976 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3977 CheckConstructor(Constructor); 3978 } else if (CXXDestructorDecl *Destructor = 3979 dyn_cast<CXXDestructorDecl>(NewFD)) { 3980 CXXRecordDecl *Record = Destructor->getParent(); 3981 QualType ClassType = Context.getTypeDeclType(Record); 3982 3983 // FIXME: Shouldn't we be able to perform this check even when the class 3984 // type is dependent? Both gcc and edg can handle that. 3985 if (!ClassType->isDependentType()) { 3986 DeclarationName Name 3987 = Context.DeclarationNames.getCXXDestructorName( 3988 Context.getCanonicalType(ClassType)); 3989 if (NewFD->getDeclName() != Name) { 3990 Diag(NewFD->getLocation(), diag::err_destructor_name); 3991 return NewFD->setInvalidDecl(); 3992 } 3993 } 3994 } else if (CXXConversionDecl *Conversion 3995 = dyn_cast<CXXConversionDecl>(NewFD)) { 3996 ActOnConversionDeclarator(Conversion); 3997 } 3998 3999 // Find any virtual functions that this function overrides. 4000 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4001 if (!Method->isFunctionTemplateSpecialization() && 4002 !Method->getDescribedFunctionTemplate()) { 4003 if (AddOverriddenMethods(Method->getParent(), Method)) { 4004 // If the function was marked as "static", we have a problem. 4005 if (NewFD->getStorageClass() == SC_Static) { 4006 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4007 << NewFD->getDeclName(); 4008 for (CXXMethodDecl::method_iterator 4009 Overridden = Method->begin_overridden_methods(), 4010 OverriddenEnd = Method->end_overridden_methods(); 4011 Overridden != OverriddenEnd; 4012 ++Overridden) { 4013 Diag((*Overridden)->getLocation(), 4014 diag::note_overridden_virtual_function); 4015 } 4016 } 4017 } 4018 } 4019 } 4020 4021 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4022 if (NewFD->isOverloadedOperator() && 4023 CheckOverloadedOperatorDeclaration(NewFD)) 4024 return NewFD->setInvalidDecl(); 4025 4026 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4027 if (NewFD->getLiteralIdentifier() && 4028 CheckLiteralOperatorDeclaration(NewFD)) 4029 return NewFD->setInvalidDecl(); 4030 4031 // In C++, check default arguments now that we have merged decls. Unless 4032 // the lexical context is the class, because in this case this is done 4033 // during delayed parsing anyway. 4034 if (!CurContext->isRecord()) 4035 CheckCXXDefaultArguments(NewFD); 4036 } 4037} 4038 4039void Sema::CheckMain(FunctionDecl* FD) { 4040 // C++ [basic.start.main]p3: A program that declares main to be inline 4041 // or static is ill-formed. 4042 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4043 // shall not appear in a declaration of main. 4044 // static main is not an error under C99, but we should warn about it. 4045 bool isInline = FD->isInlineSpecified(); 4046 bool isStatic = FD->getStorageClass() == SC_Static; 4047 if (isInline || isStatic) { 4048 unsigned diagID = diag::warn_unusual_main_decl; 4049 if (isInline || getLangOptions().CPlusPlus) 4050 diagID = diag::err_unusual_main_decl; 4051 4052 int which = isStatic + (isInline << 1) - 1; 4053 Diag(FD->getLocation(), diagID) << which; 4054 } 4055 4056 QualType T = FD->getType(); 4057 assert(T->isFunctionType() && "function decl is not of function type"); 4058 const FunctionType* FT = T->getAs<FunctionType>(); 4059 4060 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4061 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 4062 TypeLoc TL = TSI->getTypeLoc(); 4063 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 4064 diag::err_main_returns_nonint); 4065 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 4066 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4067 "int"); 4068 } 4069 FD->setInvalidDecl(true); 4070 } 4071 4072 // Treat protoless main() as nullary. 4073 if (isa<FunctionNoProtoType>(FT)) return; 4074 4075 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4076 unsigned nparams = FTP->getNumArgs(); 4077 assert(FD->getNumParams() == nparams); 4078 4079 bool HasExtraParameters = (nparams > 3); 4080 4081 // Darwin passes an undocumented fourth argument of type char**. If 4082 // other platforms start sprouting these, the logic below will start 4083 // getting shifty. 4084 if (nparams == 4 && 4085 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4086 HasExtraParameters = false; 4087 4088 if (HasExtraParameters) { 4089 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4090 FD->setInvalidDecl(true); 4091 nparams = 3; 4092 } 4093 4094 // FIXME: a lot of the following diagnostics would be improved 4095 // if we had some location information about types. 4096 4097 QualType CharPP = 4098 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4099 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4100 4101 for (unsigned i = 0; i < nparams; ++i) { 4102 QualType AT = FTP->getArgType(i); 4103 4104 bool mismatch = true; 4105 4106 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4107 mismatch = false; 4108 else if (Expected[i] == CharPP) { 4109 // As an extension, the following forms are okay: 4110 // char const ** 4111 // char const * const * 4112 // char * const * 4113 4114 QualifierCollector qs; 4115 const PointerType* PT; 4116 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4117 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4118 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4119 qs.removeConst(); 4120 mismatch = !qs.empty(); 4121 } 4122 } 4123 4124 if (mismatch) { 4125 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4126 // TODO: suggest replacing given type with expected type 4127 FD->setInvalidDecl(true); 4128 } 4129 } 4130 4131 if (nparams == 1 && !FD->isInvalidDecl()) { 4132 Diag(FD->getLocation(), diag::warn_main_one_arg); 4133 } 4134} 4135 4136bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4137 // FIXME: Need strict checking. In C89, we need to check for 4138 // any assignment, increment, decrement, function-calls, or 4139 // commas outside of a sizeof. In C99, it's the same list, 4140 // except that the aforementioned are allowed in unevaluated 4141 // expressions. Everything else falls under the 4142 // "may accept other forms of constant expressions" exception. 4143 // (We never end up here for C++, so the constant expression 4144 // rules there don't matter.) 4145 if (Init->isConstantInitializer(Context, false)) 4146 return false; 4147 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4148 << Init->getSourceRange(); 4149 return true; 4150} 4151 4152void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4153 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4154} 4155 4156/// AddInitializerToDecl - Adds the initializer Init to the 4157/// declaration dcl. If DirectInit is true, this is C++ direct 4158/// initialization rather than copy initialization. 4159void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4160 // If there is no declaration, there was an error parsing it. Just ignore 4161 // the initializer. 4162 if (RealDecl == 0) 4163 return; 4164 4165 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4166 // With declarators parsed the way they are, the parser cannot 4167 // distinguish between a normal initializer and a pure-specifier. 4168 // Thus this grotesque test. 4169 IntegerLiteral *IL; 4170 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4171 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4172 CheckPureMethod(Method, Init->getSourceRange()); 4173 else { 4174 Diag(Method->getLocation(), diag::err_member_function_initialization) 4175 << Method->getDeclName() << Init->getSourceRange(); 4176 Method->setInvalidDecl(); 4177 } 4178 return; 4179 } 4180 4181 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4182 if (!VDecl) { 4183 if (getLangOptions().CPlusPlus && 4184 RealDecl->getLexicalDeclContext()->isRecord() && 4185 isa<NamedDecl>(RealDecl)) 4186 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4187 else 4188 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4189 RealDecl->setInvalidDecl(); 4190 return; 4191 } 4192 4193 4194 4195 // A definition must end up with a complete type, which means it must be 4196 // complete with the restriction that an array type might be completed by the 4197 // initializer; note that later code assumes this restriction. 4198 QualType BaseDeclType = VDecl->getType(); 4199 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4200 BaseDeclType = Array->getElementType(); 4201 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4202 diag::err_typecheck_decl_incomplete_type)) { 4203 RealDecl->setInvalidDecl(); 4204 return; 4205 } 4206 4207 // The variable can not have an abstract class type. 4208 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4209 diag::err_abstract_type_in_decl, 4210 AbstractVariableType)) 4211 VDecl->setInvalidDecl(); 4212 4213 const VarDecl *Def; 4214 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4215 Diag(VDecl->getLocation(), diag::err_redefinition) 4216 << VDecl->getDeclName(); 4217 Diag(Def->getLocation(), diag::note_previous_definition); 4218 VDecl->setInvalidDecl(); 4219 return; 4220 } 4221 4222 // C++ [class.static.data]p4 4223 // If a static data member is of const integral or const 4224 // enumeration type, its declaration in the class definition can 4225 // specify a constant-initializer which shall be an integral 4226 // constant expression (5.19). In that case, the member can appear 4227 // in integral constant expressions. The member shall still be 4228 // defined in a namespace scope if it is used in the program and the 4229 // namespace scope definition shall not contain an initializer. 4230 // 4231 // We already performed a redefinition check above, but for static 4232 // data members we also need to check whether there was an in-class 4233 // declaration with an initializer. 4234 const VarDecl* PrevInit = 0; 4235 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4236 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4237 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4238 return; 4239 } 4240 4241 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4242 getCurFunction()->setHasBranchProtectedScope(); 4243 4244 // Capture the variable that is being initialized and the style of 4245 // initialization. 4246 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4247 4248 // FIXME: Poor source location information. 4249 InitializationKind Kind 4250 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4251 Init->getLocStart(), 4252 Init->getLocEnd()) 4253 : InitializationKind::CreateCopy(VDecl->getLocation(), 4254 Init->getLocStart()); 4255 4256 // Get the decls type and save a reference for later, since 4257 // CheckInitializerTypes may change it. 4258 QualType DclT = VDecl->getType(), SavT = DclT; 4259 if (VDecl->isLocalVarDecl()) { 4260 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4261 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4262 VDecl->setInvalidDecl(); 4263 } else if (!VDecl->isInvalidDecl()) { 4264 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4265 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4266 MultiExprArg(*this, &Init, 1), 4267 &DclT); 4268 if (Result.isInvalid()) { 4269 VDecl->setInvalidDecl(); 4270 return; 4271 } 4272 4273 Init = Result.takeAs<Expr>(); 4274 4275 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4276 // Don't check invalid declarations to avoid emitting useless diagnostics. 4277 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4278 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4279 CheckForConstantInitializer(Init, DclT); 4280 } 4281 } 4282 } else if (VDecl->isStaticDataMember() && 4283 VDecl->getLexicalDeclContext()->isRecord()) { 4284 // This is an in-class initialization for a static data member, e.g., 4285 // 4286 // struct S { 4287 // static const int value = 17; 4288 // }; 4289 4290 // Try to perform the initialization regardless. 4291 if (!VDecl->isInvalidDecl()) { 4292 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4293 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4294 MultiExprArg(*this, &Init, 1), 4295 &DclT); 4296 if (Result.isInvalid()) { 4297 VDecl->setInvalidDecl(); 4298 return; 4299 } 4300 4301 Init = Result.takeAs<Expr>(); 4302 } 4303 4304 // C++ [class.mem]p4: 4305 // A member-declarator can contain a constant-initializer only 4306 // if it declares a static member (9.4) of const integral or 4307 // const enumeration type, see 9.4.2. 4308 QualType T = VDecl->getType(); 4309 4310 // Do nothing on dependent types. 4311 if (T->isDependentType()) { 4312 4313 // Require constness. 4314 } else if (!T.isConstQualified()) { 4315 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4316 << Init->getSourceRange(); 4317 VDecl->setInvalidDecl(); 4318 4319 // We allow integer constant expressions in all cases. 4320 } else if (T->isIntegralOrEnumerationType()) { 4321 if (!Init->isValueDependent()) { 4322 // Check whether the expression is a constant expression. 4323 llvm::APSInt Value; 4324 SourceLocation Loc; 4325 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4326 Diag(Loc, diag::err_in_class_initializer_non_constant) 4327 << Init->getSourceRange(); 4328 VDecl->setInvalidDecl(); 4329 } 4330 } 4331 4332 // We allow floating-point constants as an extension in C++03, and 4333 // C++0x has far more complicated rules that we don't really 4334 // implement fully. 4335 } else { 4336 bool Allowed = false; 4337 if (getLangOptions().CPlusPlus0x) { 4338 Allowed = T->isLiteralType(); 4339 } else if (T->isFloatingType()) { // also permits complex, which is ok 4340 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4341 << T << Init->getSourceRange(); 4342 Allowed = true; 4343 } 4344 4345 if (!Allowed) { 4346 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4347 << T << Init->getSourceRange(); 4348 VDecl->setInvalidDecl(); 4349 4350 // TODO: there are probably expressions that pass here that shouldn't. 4351 } else if (!Init->isValueDependent() && 4352 !Init->isConstantInitializer(Context, false)) { 4353 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4354 << Init->getSourceRange(); 4355 VDecl->setInvalidDecl(); 4356 } 4357 } 4358 } else if (VDecl->isFileVarDecl()) { 4359 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4360 (!getLangOptions().CPlusPlus || 4361 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4362 Diag(VDecl->getLocation(), diag::warn_extern_init); 4363 if (!VDecl->isInvalidDecl()) { 4364 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4365 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4366 MultiExprArg(*this, &Init, 1), 4367 &DclT); 4368 if (Result.isInvalid()) { 4369 VDecl->setInvalidDecl(); 4370 return; 4371 } 4372 4373 Init = Result.takeAs<Expr>(); 4374 } 4375 4376 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4377 // Don't check invalid declarations to avoid emitting useless diagnostics. 4378 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4379 // C99 6.7.8p4. All file scoped initializers need to be constant. 4380 CheckForConstantInitializer(Init, DclT); 4381 } 4382 } 4383 // If the type changed, it means we had an incomplete type that was 4384 // completed by the initializer. For example: 4385 // int ary[] = { 1, 3, 5 }; 4386 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4387 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4388 VDecl->setType(DclT); 4389 Init->setType(DclT); 4390 } 4391 4392 4393 // If this variable is a local declaration with record type, make sure it 4394 // doesn't have a flexible member initialization. We only support this as a 4395 // global/static definition. 4396 if (VDecl->hasLocalStorage()) 4397 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4398 if (RT->getDecl()->hasFlexibleArrayMember()) { 4399 // Check whether the initializer tries to initialize the flexible 4400 // array member itself to anything other than an empty initializer list. 4401 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 4402 unsigned Index = std::distance(RT->getDecl()->field_begin(), 4403 RT->getDecl()->field_end()) - 1; 4404 if (Index < ILE->getNumInits() && 4405 !(isa<InitListExpr>(ILE->getInit(Index)) && 4406 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 4407 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4408 VDecl->setInvalidDecl(); 4409 } 4410 } 4411 } 4412 4413 // Check any implicit conversions within the expression. 4414 CheckImplicitConversions(Init, VDecl->getLocation()); 4415 4416 Init = MaybeCreateCXXExprWithTemporaries(Init); 4417 // Attach the initializer to the decl. 4418 VDecl->setInit(Init); 4419 4420 if (getLangOptions().CPlusPlus) { 4421 if (!VDecl->isInvalidDecl() && 4422 !VDecl->getDeclContext()->isDependentContext() && 4423 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4424 !Init->isConstantInitializer(Context, 4425 VDecl->getType()->isReferenceType())) 4426 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4427 << Init->getSourceRange(); 4428 4429 // Make sure we mark the destructor as used if necessary. 4430 QualType InitType = VDecl->getType(); 4431 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4432 InitType = Context.getBaseElementType(Array); 4433 if (const RecordType *Record = InitType->getAs<RecordType>()) 4434 FinalizeVarWithDestructor(VDecl, Record); 4435 } 4436 4437 return; 4438} 4439 4440/// ActOnInitializerError - Given that there was an error parsing an 4441/// initializer for the given declaration, try to return to some form 4442/// of sanity. 4443void Sema::ActOnInitializerError(Decl *D) { 4444 // Our main concern here is re-establishing invariants like "a 4445 // variable's type is either dependent or complete". 4446 if (!D || D->isInvalidDecl()) return; 4447 4448 VarDecl *VD = dyn_cast<VarDecl>(D); 4449 if (!VD) return; 4450 4451 QualType Ty = VD->getType(); 4452 if (Ty->isDependentType()) return; 4453 4454 // Require a complete type. 4455 if (RequireCompleteType(VD->getLocation(), 4456 Context.getBaseElementType(Ty), 4457 diag::err_typecheck_decl_incomplete_type)) { 4458 VD->setInvalidDecl(); 4459 return; 4460 } 4461 4462 // Require an abstract type. 4463 if (RequireNonAbstractType(VD->getLocation(), Ty, 4464 diag::err_abstract_type_in_decl, 4465 AbstractVariableType)) { 4466 VD->setInvalidDecl(); 4467 return; 4468 } 4469 4470 // Don't bother complaining about constructors or destructors, 4471 // though. 4472} 4473 4474void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4475 bool TypeContainsUndeducedAuto) { 4476 // If there is no declaration, there was an error parsing it. Just ignore it. 4477 if (RealDecl == 0) 4478 return; 4479 4480 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4481 QualType Type = Var->getType(); 4482 4483 // C++0x [dcl.spec.auto]p3 4484 if (TypeContainsUndeducedAuto) { 4485 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4486 << Var->getDeclName() << Type; 4487 Var->setInvalidDecl(); 4488 return; 4489 } 4490 4491 switch (Var->isThisDeclarationADefinition()) { 4492 case VarDecl::Definition: 4493 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4494 break; 4495 4496 // We have an out-of-line definition of a static data member 4497 // that has an in-class initializer, so we type-check this like 4498 // a declaration. 4499 // 4500 // Fall through 4501 4502 case VarDecl::DeclarationOnly: 4503 // It's only a declaration. 4504 4505 // Block scope. C99 6.7p7: If an identifier for an object is 4506 // declared with no linkage (C99 6.2.2p6), the type for the 4507 // object shall be complete. 4508 if (!Type->isDependentType() && Var->isLocalVarDecl() && 4509 !Var->getLinkage() && !Var->isInvalidDecl() && 4510 RequireCompleteType(Var->getLocation(), Type, 4511 diag::err_typecheck_decl_incomplete_type)) 4512 Var->setInvalidDecl(); 4513 4514 // Make sure that the type is not abstract. 4515 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4516 RequireNonAbstractType(Var->getLocation(), Type, 4517 diag::err_abstract_type_in_decl, 4518 AbstractVariableType)) 4519 Var->setInvalidDecl(); 4520 return; 4521 4522 case VarDecl::TentativeDefinition: 4523 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4524 // object that has file scope without an initializer, and without a 4525 // storage-class specifier or with the storage-class specifier "static", 4526 // constitutes a tentative definition. Note: A tentative definition with 4527 // external linkage is valid (C99 6.2.2p5). 4528 if (!Var->isInvalidDecl()) { 4529 if (const IncompleteArrayType *ArrayT 4530 = Context.getAsIncompleteArrayType(Type)) { 4531 if (RequireCompleteType(Var->getLocation(), 4532 ArrayT->getElementType(), 4533 diag::err_illegal_decl_array_incomplete_type)) 4534 Var->setInvalidDecl(); 4535 } else if (Var->getStorageClass() == SC_Static) { 4536 // C99 6.9.2p3: If the declaration of an identifier for an object is 4537 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4538 // declared type shall not be an incomplete type. 4539 // NOTE: code such as the following 4540 // static struct s; 4541 // struct s { int a; }; 4542 // is accepted by gcc. Hence here we issue a warning instead of 4543 // an error and we do not invalidate the static declaration. 4544 // NOTE: to avoid multiple warnings, only check the first declaration. 4545 if (Var->getPreviousDeclaration() == 0) 4546 RequireCompleteType(Var->getLocation(), Type, 4547 diag::ext_typecheck_decl_incomplete_type); 4548 } 4549 } 4550 4551 // Record the tentative definition; we're done. 4552 if (!Var->isInvalidDecl()) 4553 TentativeDefinitions.push_back(Var); 4554 return; 4555 } 4556 4557 // Provide a specific diagnostic for uninitialized variable 4558 // definitions with incomplete array type. 4559 if (Type->isIncompleteArrayType()) { 4560 Diag(Var->getLocation(), 4561 diag::err_typecheck_incomplete_array_needs_initializer); 4562 Var->setInvalidDecl(); 4563 return; 4564 } 4565 4566 // Provide a specific diagnostic for uninitialized variable 4567 // definitions with reference type. 4568 if (Type->isReferenceType()) { 4569 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4570 << Var->getDeclName() 4571 << SourceRange(Var->getLocation(), Var->getLocation()); 4572 Var->setInvalidDecl(); 4573 return; 4574 } 4575 4576 // Do not attempt to type-check the default initializer for a 4577 // variable with dependent type. 4578 if (Type->isDependentType()) 4579 return; 4580 4581 if (Var->isInvalidDecl()) 4582 return; 4583 4584 if (RequireCompleteType(Var->getLocation(), 4585 Context.getBaseElementType(Type), 4586 diag::err_typecheck_decl_incomplete_type)) { 4587 Var->setInvalidDecl(); 4588 return; 4589 } 4590 4591 // The variable can not have an abstract class type. 4592 if (RequireNonAbstractType(Var->getLocation(), Type, 4593 diag::err_abstract_type_in_decl, 4594 AbstractVariableType)) { 4595 Var->setInvalidDecl(); 4596 return; 4597 } 4598 4599 const RecordType *Record 4600 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4601 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4602 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4603 // C++03 [dcl.init]p9: 4604 // If no initializer is specified for an object, and the 4605 // object is of (possibly cv-qualified) non-POD class type (or 4606 // array thereof), the object shall be default-initialized; if 4607 // the object is of const-qualified type, the underlying class 4608 // type shall have a user-declared default 4609 // constructor. Otherwise, if no initializer is specified for 4610 // a non- static object, the object and its subobjects, if 4611 // any, have an indeterminate initial value); if the object 4612 // or any of its subobjects are of const-qualified type, the 4613 // program is ill-formed. 4614 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4615 } else { 4616 // Check for jumps past the implicit initializer. C++0x 4617 // clarifies that this applies to a "variable with automatic 4618 // storage duration", not a "local variable". 4619 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4620 getCurFunction()->setHasBranchProtectedScope(); 4621 4622 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4623 InitializationKind Kind 4624 = InitializationKind::CreateDefault(Var->getLocation()); 4625 4626 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4627 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4628 MultiExprArg(*this, 0, 0)); 4629 if (Init.isInvalid()) 4630 Var->setInvalidDecl(); 4631 else if (Init.get()) { 4632 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4633 4634 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4635 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4636 !Var->getDeclContext()->isDependentContext() && 4637 !Var->getInit()->isConstantInitializer(Context, false)) 4638 Diag(Var->getLocation(), diag::warn_global_constructor); 4639 } 4640 } 4641 4642 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4643 FinalizeVarWithDestructor(Var, Record); 4644 } 4645} 4646 4647Sema::DeclGroupPtrTy 4648Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4649 Decl **Group, unsigned NumDecls) { 4650 llvm::SmallVector<Decl*, 8> Decls; 4651 4652 if (DS.isTypeSpecOwned()) 4653 Decls.push_back(DS.getRepAsDecl()); 4654 4655 for (unsigned i = 0; i != NumDecls; ++i) 4656 if (Decl *D = Group[i]) 4657 Decls.push_back(D); 4658 4659 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4660 Decls.data(), Decls.size())); 4661} 4662 4663 4664/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4665/// to introduce parameters into function prototype scope. 4666Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4667 const DeclSpec &DS = D.getDeclSpec(); 4668 4669 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4670 VarDecl::StorageClass StorageClass = SC_None; 4671 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4672 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4673 StorageClass = SC_Register; 4674 StorageClassAsWritten = SC_Register; 4675 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4676 Diag(DS.getStorageClassSpecLoc(), 4677 diag::err_invalid_storage_class_in_func_decl); 4678 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4679 } 4680 4681 if (D.getDeclSpec().isThreadSpecified()) 4682 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4683 4684 DiagnoseFunctionSpecifiers(D); 4685 4686 // Check that there are no default arguments inside the type of this 4687 // parameter (C++ only). 4688 if (getLangOptions().CPlusPlus) 4689 CheckExtraCXXDefaultArguments(D); 4690 4691 TagDecl *OwnedDecl = 0; 4692 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4693 QualType parmDeclType = TInfo->getType(); 4694 4695 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4696 // C++ [dcl.fct]p6: 4697 // Types shall not be defined in return or parameter types. 4698 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4699 << Context.getTypeDeclType(OwnedDecl); 4700 } 4701 4702 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4703 IdentifierInfo *II = D.getIdentifier(); 4704 if (II) { 4705 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4706 ForRedeclaration); 4707 LookupName(R, S); 4708 if (R.isSingleResult()) { 4709 NamedDecl *PrevDecl = R.getFoundDecl(); 4710 if (PrevDecl->isTemplateParameter()) { 4711 // Maybe we will complain about the shadowed template parameter. 4712 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4713 // Just pretend that we didn't see the previous declaration. 4714 PrevDecl = 0; 4715 } else if (S->isDeclScope(PrevDecl)) { 4716 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4717 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4718 4719 // Recover by removing the name 4720 II = 0; 4721 D.SetIdentifier(0, D.getIdentifierLoc()); 4722 D.setInvalidType(true); 4723 } 4724 } 4725 } 4726 4727 // Temporarily put parameter variables in the translation unit, not 4728 // the enclosing context. This prevents them from accidentally 4729 // looking like class members in C++. 4730 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4731 TInfo, parmDeclType, II, 4732 D.getIdentifierLoc(), 4733 StorageClass, StorageClassAsWritten); 4734 4735 if (D.isInvalidType()) 4736 New->setInvalidDecl(); 4737 4738 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4739 if (D.getCXXScopeSpec().isSet()) { 4740 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4741 << D.getCXXScopeSpec().getRange(); 4742 New->setInvalidDecl(); 4743 } 4744 4745 // Add the parameter declaration into this scope. 4746 S->AddDecl(New); 4747 if (II) 4748 IdResolver.AddDecl(New); 4749 4750 ProcessDeclAttributes(S, New, D); 4751 4752 if (New->hasAttr<BlocksAttr>()) { 4753 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4754 } 4755 return New; 4756} 4757 4758/// \brief Synthesizes a variable for a parameter arising from a 4759/// typedef. 4760ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4761 SourceLocation Loc, 4762 QualType T) { 4763 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4764 T, Context.getTrivialTypeSourceInfo(T, Loc), 4765 SC_None, SC_None, 0); 4766 Param->setImplicit(); 4767 return Param; 4768} 4769 4770void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4771 ParmVarDecl * const *ParamEnd) { 4772 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4773 Diagnostic::Ignored) 4774 return; 4775 4776 // Don't diagnose unused-parameter errors in template instantiations; we 4777 // will already have done so in the template itself. 4778 if (!ActiveTemplateInstantiations.empty()) 4779 return; 4780 4781 for (; Param != ParamEnd; ++Param) { 4782 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4783 !(*Param)->hasAttr<UnusedAttr>()) { 4784 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4785 << (*Param)->getDeclName(); 4786 } 4787 } 4788} 4789 4790ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4791 TypeSourceInfo *TSInfo, QualType T, 4792 IdentifierInfo *Name, 4793 SourceLocation NameLoc, 4794 VarDecl::StorageClass StorageClass, 4795 VarDecl::StorageClass StorageClassAsWritten) { 4796 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4797 adjustParameterType(T), TSInfo, 4798 StorageClass, StorageClassAsWritten, 4799 0); 4800 4801 // Parameters can not be abstract class types. 4802 // For record types, this is done by the AbstractClassUsageDiagnoser once 4803 // the class has been completely parsed. 4804 if (!CurContext->isRecord() && 4805 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4806 AbstractParamType)) 4807 New->setInvalidDecl(); 4808 4809 // Parameter declarators cannot be interface types. All ObjC objects are 4810 // passed by reference. 4811 if (T->isObjCObjectType()) { 4812 Diag(NameLoc, 4813 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4814 New->setInvalidDecl(); 4815 } 4816 4817 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4818 // duration shall not be qualified by an address-space qualifier." 4819 // Since all parameters have automatic store duration, they can not have 4820 // an address space. 4821 if (T.getAddressSpace() != 0) { 4822 Diag(NameLoc, diag::err_arg_with_address_space); 4823 New->setInvalidDecl(); 4824 } 4825 4826 return New; 4827} 4828 4829void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4830 SourceLocation LocAfterDecls) { 4831 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4832 "Not a function declarator!"); 4833 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4834 4835 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4836 // for a K&R function. 4837 if (!FTI.hasPrototype) { 4838 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4839 --i; 4840 if (FTI.ArgInfo[i].Param == 0) { 4841 llvm::SmallString<256> Code; 4842 llvm::raw_svector_ostream(Code) << " int " 4843 << FTI.ArgInfo[i].Ident->getName() 4844 << ";\n"; 4845 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4846 << FTI.ArgInfo[i].Ident 4847 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4848 4849 // Implicitly declare the argument as type 'int' for lack of a better 4850 // type. 4851 DeclSpec DS; 4852 const char* PrevSpec; // unused 4853 unsigned DiagID; // unused 4854 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4855 PrevSpec, DiagID); 4856 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4857 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4858 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4859 } 4860 } 4861 } 4862} 4863 4864Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4865 Declarator &D) { 4866 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4867 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4868 "Not a function declarator!"); 4869 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4870 4871 if (FTI.hasPrototype) { 4872 // FIXME: Diagnose arguments without names in C. 4873 } 4874 4875 Scope *ParentScope = FnBodyScope->getParent(); 4876 4877 Decl *DP = HandleDeclarator(ParentScope, D, 4878 MultiTemplateParamsArg(*this), 4879 /*IsFunctionDefinition=*/true); 4880 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4881} 4882 4883static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4884 // Don't warn about invalid declarations. 4885 if (FD->isInvalidDecl()) 4886 return false; 4887 4888 // Or declarations that aren't global. 4889 if (!FD->isGlobal()) 4890 return false; 4891 4892 // Don't warn about C++ member functions. 4893 if (isa<CXXMethodDecl>(FD)) 4894 return false; 4895 4896 // Don't warn about 'main'. 4897 if (FD->isMain()) 4898 return false; 4899 4900 // Don't warn about inline functions. 4901 if (FD->isInlineSpecified()) 4902 return false; 4903 4904 // Don't warn about function templates. 4905 if (FD->getDescribedFunctionTemplate()) 4906 return false; 4907 4908 // Don't warn about function template specializations. 4909 if (FD->isFunctionTemplateSpecialization()) 4910 return false; 4911 4912 bool MissingPrototype = true; 4913 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4914 Prev; Prev = Prev->getPreviousDeclaration()) { 4915 // Ignore any declarations that occur in function or method 4916 // scope, because they aren't visible from the header. 4917 if (Prev->getDeclContext()->isFunctionOrMethod()) 4918 continue; 4919 4920 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4921 break; 4922 } 4923 4924 return MissingPrototype; 4925} 4926 4927Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4928 // Clear the last template instantiation error context. 4929 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4930 4931 if (!D) 4932 return D; 4933 FunctionDecl *FD = 0; 4934 4935 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4936 FD = FunTmpl->getTemplatedDecl(); 4937 else 4938 FD = cast<FunctionDecl>(D); 4939 4940 // Enter a new function scope 4941 PushFunctionScope(); 4942 4943 // See if this is a redefinition. 4944 // But don't complain if we're in GNU89 mode and the previous definition 4945 // was an extern inline function. 4946 const FunctionDecl *Definition; 4947 if (FD->hasBody(Definition) && 4948 !canRedefineFunction(Definition, getLangOptions())) { 4949 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 4950 Definition->getStorageClass() == SC_Extern) 4951 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 4952 << FD->getDeclName() << getLangOptions().CPlusPlus; 4953 else 4954 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4955 Diag(Definition->getLocation(), diag::note_previous_definition); 4956 } 4957 4958 // Builtin functions cannot be defined. 4959 if (unsigned BuiltinID = FD->getBuiltinID()) { 4960 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4961 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4962 FD->setInvalidDecl(); 4963 } 4964 } 4965 4966 // The return type of a function definition must be complete 4967 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4968 QualType ResultType = FD->getResultType(); 4969 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4970 !FD->isInvalidDecl() && 4971 RequireCompleteType(FD->getLocation(), ResultType, 4972 diag::err_func_def_incomplete_result)) 4973 FD->setInvalidDecl(); 4974 4975 // GNU warning -Wmissing-prototypes: 4976 // Warn if a global function is defined without a previous 4977 // prototype declaration. This warning is issued even if the 4978 // definition itself provides a prototype. The aim is to detect 4979 // global functions that fail to be declared in header files. 4980 if (ShouldWarnAboutMissingPrototype(FD)) 4981 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4982 4983 if (FnBodyScope) 4984 PushDeclContext(FnBodyScope, FD); 4985 4986 // Check the validity of our function parameters 4987 CheckParmsForFunctionDef(FD); 4988 4989 bool ShouldCheckShadow = 4990 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4991 4992 // Introduce our parameters into the function scope 4993 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4994 ParmVarDecl *Param = FD->getParamDecl(p); 4995 Param->setOwningFunction(FD); 4996 4997 // If this has an identifier, add it to the scope stack. 4998 if (Param->getIdentifier() && FnBodyScope) { 4999 if (ShouldCheckShadow) 5000 CheckShadow(FnBodyScope, Param); 5001 5002 PushOnScopeChains(Param, FnBodyScope); 5003 } 5004 } 5005 5006 // Checking attributes of current function definition 5007 // dllimport attribute. 5008 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5009 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5010 // dllimport attribute cannot be directly applied to definition. 5011 if (!DA->isInherited()) { 5012 Diag(FD->getLocation(), 5013 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5014 << "dllimport"; 5015 FD->setInvalidDecl(); 5016 return FD; 5017 } 5018 5019 // Visual C++ appears to not think this is an issue, so only issue 5020 // a warning when Microsoft extensions are disabled. 5021 if (!LangOpts.Microsoft) { 5022 // If a symbol previously declared dllimport is later defined, the 5023 // attribute is ignored in subsequent references, and a warning is 5024 // emitted. 5025 Diag(FD->getLocation(), 5026 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5027 << FD->getName() << "dllimport"; 5028 } 5029 } 5030 return FD; 5031} 5032 5033/// \brief Given the set of return statements within a function body, 5034/// compute the variables that are subject to the named return value 5035/// optimization. 5036/// 5037/// Each of the variables that is subject to the named return value 5038/// optimization will be marked as NRVO variables in the AST, and any 5039/// return statement that has a marked NRVO variable as its NRVO candidate can 5040/// use the named return value optimization. 5041/// 5042/// This function applies a very simplistic algorithm for NRVO: if every return 5043/// statement in the function has the same NRVO candidate, that candidate is 5044/// the NRVO variable. 5045/// 5046/// FIXME: Employ a smarter algorithm that accounts for multiple return 5047/// statements and the lifetimes of the NRVO candidates. We should be able to 5048/// find a maximal set of NRVO variables. 5049static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5050 ReturnStmt **Returns = Scope->Returns.data(); 5051 5052 const VarDecl *NRVOCandidate = 0; 5053 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5054 if (!Returns[I]->getNRVOCandidate()) 5055 return; 5056 5057 if (!NRVOCandidate) 5058 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5059 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5060 return; 5061 } 5062 5063 if (NRVOCandidate) 5064 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5065} 5066 5067Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5068 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5069} 5070 5071Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5072 bool IsInstantiation) { 5073 FunctionDecl *FD = 0; 5074 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5075 if (FunTmpl) 5076 FD = FunTmpl->getTemplatedDecl(); 5077 else 5078 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5079 5080 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5081 5082 if (FD) { 5083 FD->setBody(Body); 5084 if (FD->isMain()) { 5085 // C and C++ allow for main to automagically return 0. 5086 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5087 FD->setHasImplicitReturnZero(true); 5088 WP.disableCheckFallThrough(); 5089 } 5090 5091 if (!FD->isInvalidDecl()) { 5092 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5093 5094 // If this is a constructor, we need a vtable. 5095 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5096 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5097 5098 ComputeNRVO(Body, getCurFunction()); 5099 } 5100 5101 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5102 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5103 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5104 MD->setBody(Body); 5105 MD->setEndLoc(Body->getLocEnd()); 5106 if (!MD->isInvalidDecl()) 5107 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5108 } else { 5109 return 0; 5110 } 5111 5112 // Verify and clean out per-function state. 5113 5114 // Check goto/label use. 5115 FunctionScopeInfo *CurFn = getCurFunction(); 5116 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5117 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5118 LabelStmt *L = I->second; 5119 5120 // Verify that we have no forward references left. If so, there was a goto 5121 // or address of a label taken, but no definition of it. Label fwd 5122 // definitions are indicated with a null substmt. 5123 if (L->getSubStmt() != 0) { 5124 if (!L->isUsed()) 5125 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5126 continue; 5127 } 5128 5129 // Emit error. 5130 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5131 5132 // At this point, we have gotos that use the bogus label. Stitch it into 5133 // the function body so that they aren't leaked and that the AST is well 5134 // formed. 5135 if (Body == 0) { 5136 // The whole function wasn't parsed correctly. 5137 continue; 5138 } 5139 5140 // Otherwise, the body is valid: we want to stitch the label decl into the 5141 // function somewhere so that it is properly owned and so that the goto 5142 // has a valid target. Do this by creating a new compound stmt with the 5143 // label in it. 5144 5145 // Give the label a sub-statement. 5146 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5147 5148 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5149 cast<CXXTryStmt>(Body)->getTryBlock() : 5150 cast<CompoundStmt>(Body); 5151 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5152 Compound->body_end()); 5153 Elements.push_back(L); 5154 Compound->setStmts(Context, Elements.data(), Elements.size()); 5155 } 5156 5157 if (Body) { 5158 // C++ constructors that have function-try-blocks can't have return 5159 // statements in the handlers of that block. (C++ [except.handle]p14) 5160 // Verify this. 5161 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5162 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5163 5164 // Verify that that gotos and switch cases don't jump into scopes illegally. 5165 // Verify that that gotos and switch cases don't jump into scopes illegally. 5166 if (getCurFunction()->NeedsScopeChecking() && 5167 !dcl->isInvalidDecl() && 5168 !hasAnyErrorsInThisFunction()) 5169 DiagnoseInvalidJumps(Body); 5170 5171 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5172 if (!Destructor->getParent()->isDependentType()) 5173 CheckDestructor(Destructor); 5174 5175 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5176 Destructor->getParent()); 5177 } 5178 5179 // If any errors have occurred, clear out any temporaries that may have 5180 // been leftover. This ensures that these temporaries won't be picked up for 5181 // deletion in some later function. 5182 if (PP.getDiagnostics().hasErrorOccurred()) 5183 ExprTemporaries.clear(); 5184 else if (!isa<FunctionTemplateDecl>(dcl)) { 5185 // Since the body is valid, issue any analysis-based warnings that are 5186 // enabled. 5187 QualType ResultType; 5188 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5189 AnalysisWarnings.IssueWarnings(WP, FD); 5190 } else { 5191 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5192 AnalysisWarnings.IssueWarnings(WP, MD); 5193 } 5194 } 5195 5196 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5197 } 5198 5199 if (!IsInstantiation) 5200 PopDeclContext(); 5201 5202 PopFunctionOrBlockScope(); 5203 5204 // If any errors have occurred, clear out any temporaries that may have 5205 // been leftover. This ensures that these temporaries won't be picked up for 5206 // deletion in some later function. 5207 if (getDiagnostics().hasErrorOccurred()) 5208 ExprTemporaries.clear(); 5209 5210 return dcl; 5211} 5212 5213/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5214/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5215NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5216 IdentifierInfo &II, Scope *S) { 5217 // Before we produce a declaration for an implicitly defined 5218 // function, see whether there was a locally-scoped declaration of 5219 // this name as a function or variable. If so, use that 5220 // (non-visible) declaration, and complain about it. 5221 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5222 = LocallyScopedExternalDecls.find(&II); 5223 if (Pos != LocallyScopedExternalDecls.end()) { 5224 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5225 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5226 return Pos->second; 5227 } 5228 5229 // Extension in C99. Legal in C90, but warn about it. 5230 if (II.getName().startswith("__builtin_")) 5231 Diag(Loc, diag::warn_builtin_unknown) << &II; 5232 else if (getLangOptions().C99) 5233 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5234 else 5235 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5236 5237 // Set a Declarator for the implicit definition: int foo(); 5238 const char *Dummy; 5239 DeclSpec DS; 5240 unsigned DiagID; 5241 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5242 Error = Error; // Silence warning. 5243 assert(!Error && "Error setting up implicit decl!"); 5244 Declarator D(DS, Declarator::BlockContext); 5245 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5246 0, 0, false, SourceLocation(), 5247 false, 0,0,0, Loc, Loc, D), 5248 SourceLocation()); 5249 D.SetIdentifier(&II, Loc); 5250 5251 // Insert this function into translation-unit scope. 5252 5253 DeclContext *PrevDC = CurContext; 5254 CurContext = Context.getTranslationUnitDecl(); 5255 5256 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5257 FD->setImplicit(); 5258 5259 CurContext = PrevDC; 5260 5261 AddKnownFunctionAttributes(FD); 5262 5263 return FD; 5264} 5265 5266/// \brief Adds any function attributes that we know a priori based on 5267/// the declaration of this function. 5268/// 5269/// These attributes can apply both to implicitly-declared builtins 5270/// (like __builtin___printf_chk) or to library-declared functions 5271/// like NSLog or printf. 5272void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5273 if (FD->isInvalidDecl()) 5274 return; 5275 5276 // If this is a built-in function, map its builtin attributes to 5277 // actual attributes. 5278 if (unsigned BuiltinID = FD->getBuiltinID()) { 5279 // Handle printf-formatting attributes. 5280 unsigned FormatIdx; 5281 bool HasVAListArg; 5282 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5283 if (!FD->getAttr<FormatAttr>()) 5284 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5285 "printf", FormatIdx+1, 5286 HasVAListArg ? 0 : FormatIdx+2)); 5287 } 5288 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5289 HasVAListArg)) { 5290 if (!FD->getAttr<FormatAttr>()) 5291 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5292 "scanf", FormatIdx+1, 5293 HasVAListArg ? 0 : FormatIdx+2)); 5294 } 5295 5296 // Mark const if we don't care about errno and that is the only 5297 // thing preventing the function from being const. This allows 5298 // IRgen to use LLVM intrinsics for such functions. 5299 if (!getLangOptions().MathErrno && 5300 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5301 if (!FD->getAttr<ConstAttr>()) 5302 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5303 } 5304 5305 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5306 FD->setType(Context.getNoReturnType(FD->getType())); 5307 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5308 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5309 if (Context.BuiltinInfo.isConst(BuiltinID)) 5310 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5311 } 5312 5313 IdentifierInfo *Name = FD->getIdentifier(); 5314 if (!Name) 5315 return; 5316 if ((!getLangOptions().CPlusPlus && 5317 FD->getDeclContext()->isTranslationUnit()) || 5318 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5319 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5320 LinkageSpecDecl::lang_c)) { 5321 // Okay: this could be a libc/libm/Objective-C function we know 5322 // about. 5323 } else 5324 return; 5325 5326 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5327 // FIXME: NSLog and NSLogv should be target specific 5328 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5329 // FIXME: We known better than our headers. 5330 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5331 } else 5332 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5333 "printf", 1, 5334 Name->isStr("NSLogv") ? 0 : 2)); 5335 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5336 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5337 // target-specific builtins, perhaps? 5338 if (!FD->getAttr<FormatAttr>()) 5339 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5340 "printf", 2, 5341 Name->isStr("vasprintf") ? 0 : 3)); 5342 } 5343} 5344 5345TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5346 TypeSourceInfo *TInfo) { 5347 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5348 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5349 5350 if (!TInfo) { 5351 assert(D.isInvalidType() && "no declarator info for valid type"); 5352 TInfo = Context.getTrivialTypeSourceInfo(T); 5353 } 5354 5355 // Scope manipulation handled by caller. 5356 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5357 D.getIdentifierLoc(), 5358 D.getIdentifier(), 5359 TInfo); 5360 5361 if (const TagType *TT = T->getAs<TagType>()) { 5362 TagDecl *TD = TT->getDecl(); 5363 5364 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5365 // keep track of the TypedefDecl. 5366 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5367 TD->setTypedefForAnonDecl(NewTD); 5368 } 5369 5370 if (D.isInvalidType()) 5371 NewTD->setInvalidDecl(); 5372 return NewTD; 5373} 5374 5375 5376/// \brief Determine whether a tag with a given kind is acceptable 5377/// as a redeclaration of the given tag declaration. 5378/// 5379/// \returns true if the new tag kind is acceptable, false otherwise. 5380bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5381 TagTypeKind NewTag, 5382 SourceLocation NewTagLoc, 5383 const IdentifierInfo &Name) { 5384 // C++ [dcl.type.elab]p3: 5385 // The class-key or enum keyword present in the 5386 // elaborated-type-specifier shall agree in kind with the 5387 // declaration to which the name in the elaborated-type-specifier 5388 // refers. This rule also applies to the form of 5389 // elaborated-type-specifier that declares a class-name or 5390 // friend class since it can be construed as referring to the 5391 // definition of the class. Thus, in any 5392 // elaborated-type-specifier, the enum keyword shall be used to 5393 // refer to an enumeration (7.2), the union class-key shall be 5394 // used to refer to a union (clause 9), and either the class or 5395 // struct class-key shall be used to refer to a class (clause 9) 5396 // declared using the class or struct class-key. 5397 TagTypeKind OldTag = Previous->getTagKind(); 5398 if (OldTag == NewTag) 5399 return true; 5400 5401 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5402 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5403 // Warn about the struct/class tag mismatch. 5404 bool isTemplate = false; 5405 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5406 isTemplate = Record->getDescribedClassTemplate(); 5407 5408 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5409 << (NewTag == TTK_Class) 5410 << isTemplate << &Name 5411 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5412 OldTag == TTK_Class? "class" : "struct"); 5413 Diag(Previous->getLocation(), diag::note_previous_use); 5414 return true; 5415 } 5416 return false; 5417} 5418 5419/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5420/// former case, Name will be non-null. In the later case, Name will be null. 5421/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5422/// reference/declaration/definition of a tag. 5423Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5424 SourceLocation KWLoc, CXXScopeSpec &SS, 5425 IdentifierInfo *Name, SourceLocation NameLoc, 5426 AttributeList *Attr, AccessSpecifier AS, 5427 MultiTemplateParamsArg TemplateParameterLists, 5428 bool &OwnedDecl, bool &IsDependent, bool ScopedEnum, 5429 TypeResult UnderlyingType) { 5430 // If this is not a definition, it must have a name. 5431 assert((Name != 0 || TUK == TUK_Definition) && 5432 "Nameless record must be a definition!"); 5433 5434 OwnedDecl = false; 5435 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5436 5437 // FIXME: Check explicit specializations more carefully. 5438 bool isExplicitSpecialization = false; 5439 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5440 bool Invalid = false; 5441 if (TUK != TUK_Reference) { 5442 if (TemplateParameterList *TemplateParams 5443 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5444 (TemplateParameterList**)TemplateParameterLists.get(), 5445 TemplateParameterLists.size(), 5446 TUK == TUK_Friend, 5447 isExplicitSpecialization, 5448 Invalid)) { 5449 // All but one template parameter lists have been matching. 5450 --NumMatchedTemplateParamLists; 5451 5452 if (TemplateParams->size() > 0) { 5453 // This is a declaration or definition of a class template (which may 5454 // be a member of another template). 5455 if (Invalid) 5456 return 0; 5457 5458 OwnedDecl = false; 5459 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5460 SS, Name, NameLoc, Attr, 5461 TemplateParams, 5462 AS); 5463 TemplateParameterLists.release(); 5464 return Result.get(); 5465 } else { 5466 // The "template<>" header is extraneous. 5467 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5468 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5469 isExplicitSpecialization = true; 5470 } 5471 } 5472 } 5473 5474 // Figure out the underlying type if this a enum declaration. We need to do 5475 // this early, because it's needed to detect if this is an incompatible 5476 // redeclaration. 5477 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 5478 5479 if (Kind == TTK_Enum) { 5480 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 5481 // No underlying type explicitly specified, or we failed to parse the 5482 // type, default to int. 5483 EnumUnderlying = Context.IntTy.getTypePtr(); 5484 else if (UnderlyingType.get()) { 5485 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 5486 // integral type; any cv-qualification is ignored. 5487 TypeSourceInfo *TI = 0; 5488 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 5489 EnumUnderlying = TI; 5490 5491 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 5492 5493 if (!T->isDependentType() && !T->isIntegralType(Context)) { 5494 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 5495 << T; 5496 // Recover by falling back to int. 5497 EnumUnderlying = Context.IntTy.getTypePtr(); 5498 } 5499 } 5500 } 5501 5502 DeclContext *SearchDC = CurContext; 5503 DeclContext *DC = CurContext; 5504 bool isStdBadAlloc = false; 5505 5506 RedeclarationKind Redecl = ForRedeclaration; 5507 if (TUK == TUK_Friend || TUK == TUK_Reference) 5508 Redecl = NotForRedeclaration; 5509 5510 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5511 5512 if (Name && SS.isNotEmpty()) { 5513 // We have a nested-name tag ('struct foo::bar'). 5514 5515 // Check for invalid 'foo::'. 5516 if (SS.isInvalid()) { 5517 Name = 0; 5518 goto CreateNewDecl; 5519 } 5520 5521 // If this is a friend or a reference to a class in a dependent 5522 // context, don't try to make a decl for it. 5523 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5524 DC = computeDeclContext(SS, false); 5525 if (!DC) { 5526 IsDependent = true; 5527 return 0; 5528 } 5529 } else { 5530 DC = computeDeclContext(SS, true); 5531 if (!DC) { 5532 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5533 << SS.getRange(); 5534 return 0; 5535 } 5536 } 5537 5538 if (RequireCompleteDeclContext(SS, DC)) 5539 return 0; 5540 5541 SearchDC = DC; 5542 // Look-up name inside 'foo::'. 5543 LookupQualifiedName(Previous, DC); 5544 5545 if (Previous.isAmbiguous()) 5546 return 0; 5547 5548 if (Previous.empty()) { 5549 // Name lookup did not find anything. However, if the 5550 // nested-name-specifier refers to the current instantiation, 5551 // and that current instantiation has any dependent base 5552 // classes, we might find something at instantiation time: treat 5553 // this as a dependent elaborated-type-specifier. 5554 if (Previous.wasNotFoundInCurrentInstantiation()) { 5555 IsDependent = true; 5556 return 0; 5557 } 5558 5559 // A tag 'foo::bar' must already exist. 5560 Diag(NameLoc, diag::err_not_tag_in_scope) 5561 << Kind << Name << DC << SS.getRange(); 5562 Name = 0; 5563 Invalid = true; 5564 goto CreateNewDecl; 5565 } 5566 } else if (Name) { 5567 // If this is a named struct, check to see if there was a previous forward 5568 // declaration or definition. 5569 // FIXME: We're looking into outer scopes here, even when we 5570 // shouldn't be. Doing so can result in ambiguities that we 5571 // shouldn't be diagnosing. 5572 LookupName(Previous, S); 5573 5574 // Note: there used to be some attempt at recovery here. 5575 if (Previous.isAmbiguous()) 5576 return 0; 5577 5578 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5579 // FIXME: This makes sure that we ignore the contexts associated 5580 // with C structs, unions, and enums when looking for a matching 5581 // tag declaration or definition. See the similar lookup tweak 5582 // in Sema::LookupName; is there a better way to deal with this? 5583 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5584 SearchDC = SearchDC->getParent(); 5585 } 5586 } else if (S->isFunctionPrototypeScope()) { 5587 // If this is an enum declaration in function prototype scope, set its 5588 // initial context to the translation unit. 5589 SearchDC = Context.getTranslationUnitDecl(); 5590 } 5591 5592 if (Previous.isSingleResult() && 5593 Previous.getFoundDecl()->isTemplateParameter()) { 5594 // Maybe we will complain about the shadowed template parameter. 5595 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5596 // Just pretend that we didn't see the previous declaration. 5597 Previous.clear(); 5598 } 5599 5600 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5601 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5602 // This is a declaration of or a reference to "std::bad_alloc". 5603 isStdBadAlloc = true; 5604 5605 if (Previous.empty() && StdBadAlloc) { 5606 // std::bad_alloc has been implicitly declared (but made invisible to 5607 // name lookup). Fill in this implicit declaration as the previous 5608 // declaration, so that the declarations get chained appropriately. 5609 Previous.addDecl(getStdBadAlloc()); 5610 } 5611 } 5612 5613 // If we didn't find a previous declaration, and this is a reference 5614 // (or friend reference), move to the correct scope. In C++, we 5615 // also need to do a redeclaration lookup there, just in case 5616 // there's a shadow friend decl. 5617 if (Name && Previous.empty() && 5618 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5619 if (Invalid) goto CreateNewDecl; 5620 assert(SS.isEmpty()); 5621 5622 if (TUK == TUK_Reference) { 5623 // C++ [basic.scope.pdecl]p5: 5624 // -- for an elaborated-type-specifier of the form 5625 // 5626 // class-key identifier 5627 // 5628 // if the elaborated-type-specifier is used in the 5629 // decl-specifier-seq or parameter-declaration-clause of a 5630 // function defined in namespace scope, the identifier is 5631 // declared as a class-name in the namespace that contains 5632 // the declaration; otherwise, except as a friend 5633 // declaration, the identifier is declared in the smallest 5634 // non-class, non-function-prototype scope that contains the 5635 // declaration. 5636 // 5637 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5638 // C structs and unions. 5639 // 5640 // It is an error in C++ to declare (rather than define) an enum 5641 // type, including via an elaborated type specifier. We'll 5642 // diagnose that later; for now, declare the enum in the same 5643 // scope as we would have picked for any other tag type. 5644 // 5645 // GNU C also supports this behavior as part of its incomplete 5646 // enum types extension, while GNU C++ does not. 5647 // 5648 // Find the context where we'll be declaring the tag. 5649 // FIXME: We would like to maintain the current DeclContext as the 5650 // lexical context, 5651 while (SearchDC->isRecord()) 5652 SearchDC = SearchDC->getParent(); 5653 5654 // Find the scope where we'll be declaring the tag. 5655 while (S->isClassScope() || 5656 (getLangOptions().CPlusPlus && 5657 S->isFunctionPrototypeScope()) || 5658 ((S->getFlags() & Scope::DeclScope) == 0) || 5659 (S->getEntity() && 5660 ((DeclContext *)S->getEntity())->isTransparentContext())) 5661 S = S->getParent(); 5662 } else { 5663 assert(TUK == TUK_Friend); 5664 // C++ [namespace.memdef]p3: 5665 // If a friend declaration in a non-local class first declares a 5666 // class or function, the friend class or function is a member of 5667 // the innermost enclosing namespace. 5668 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5669 } 5670 5671 // In C++, we need to do a redeclaration lookup to properly 5672 // diagnose some problems. 5673 if (getLangOptions().CPlusPlus) { 5674 Previous.setRedeclarationKind(ForRedeclaration); 5675 LookupQualifiedName(Previous, SearchDC); 5676 } 5677 } 5678 5679 if (!Previous.empty()) { 5680 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5681 5682 // It's okay to have a tag decl in the same scope as a typedef 5683 // which hides a tag decl in the same scope. Finding this 5684 // insanity with a redeclaration lookup can only actually happen 5685 // in C++. 5686 // 5687 // This is also okay for elaborated-type-specifiers, which is 5688 // technically forbidden by the current standard but which is 5689 // okay according to the likely resolution of an open issue; 5690 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5691 if (getLangOptions().CPlusPlus) { 5692 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5693 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5694 TagDecl *Tag = TT->getDecl(); 5695 if (Tag->getDeclName() == Name && 5696 Tag->getDeclContext()->getRedeclContext() 5697 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5698 PrevDecl = Tag; 5699 Previous.clear(); 5700 Previous.addDecl(Tag); 5701 Previous.resolveKind(); 5702 } 5703 } 5704 } 5705 } 5706 5707 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5708 // If this is a use of a previous tag, or if the tag is already declared 5709 // in the same scope (so that the definition/declaration completes or 5710 // rementions the tag), reuse the decl. 5711 if (TUK == TUK_Reference || TUK == TUK_Friend || 5712 isDeclInScope(PrevDecl, SearchDC, S)) { 5713 // Make sure that this wasn't declared as an enum and now used as a 5714 // struct or something similar. 5715 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5716 bool SafeToContinue 5717 = (PrevTagDecl->getTagKind() != TTK_Enum && 5718 Kind != TTK_Enum); 5719 if (SafeToContinue) 5720 Diag(KWLoc, diag::err_use_with_wrong_tag) 5721 << Name 5722 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5723 PrevTagDecl->getKindName()); 5724 else 5725 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5726 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5727 5728 if (SafeToContinue) 5729 Kind = PrevTagDecl->getTagKind(); 5730 else { 5731 // Recover by making this an anonymous redefinition. 5732 Name = 0; 5733 Previous.clear(); 5734 Invalid = true; 5735 } 5736 } 5737 5738 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 5739 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 5740 5741 // All conflicts with previous declarations are recovered by 5742 // returning the previous declaration. 5743 if (ScopedEnum != PrevEnum->isScoped()) { 5744 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 5745 << PrevEnum->isScoped(); 5746 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5747 return PrevTagDecl; 5748 } 5749 else if (EnumUnderlying && PrevEnum->isFixed()) { 5750 QualType T; 5751 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5752 T = TI->getType(); 5753 else 5754 T = QualType(EnumUnderlying.get<const Type*>(), 0); 5755 5756 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 5757 Diag(KWLoc, diag::err_enum_redeclare_type_mismatch); 5758 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5759 return PrevTagDecl; 5760 } 5761 } 5762 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 5763 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 5764 << PrevEnum->isFixed(); 5765 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5766 return PrevTagDecl; 5767 } 5768 } 5769 5770 if (!Invalid) { 5771 // If this is a use, just return the declaration we found. 5772 5773 // FIXME: In the future, return a variant or some other clue 5774 // for the consumer of this Decl to know it doesn't own it. 5775 // For our current ASTs this shouldn't be a problem, but will 5776 // need to be changed with DeclGroups. 5777 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5778 TUK == TUK_Friend) 5779 return PrevTagDecl; 5780 5781 // Diagnose attempts to redefine a tag. 5782 if (TUK == TUK_Definition) { 5783 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5784 // If we're defining a specialization and the previous definition 5785 // is from an implicit instantiation, don't emit an error 5786 // here; we'll catch this in the general case below. 5787 if (!isExplicitSpecialization || 5788 !isa<CXXRecordDecl>(Def) || 5789 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5790 == TSK_ExplicitSpecialization) { 5791 Diag(NameLoc, diag::err_redefinition) << Name; 5792 Diag(Def->getLocation(), diag::note_previous_definition); 5793 // If this is a redefinition, recover by making this 5794 // struct be anonymous, which will make any later 5795 // references get the previous definition. 5796 Name = 0; 5797 Previous.clear(); 5798 Invalid = true; 5799 } 5800 } else { 5801 // If the type is currently being defined, complain 5802 // about a nested redefinition. 5803 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5804 if (Tag->isBeingDefined()) { 5805 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5806 Diag(PrevTagDecl->getLocation(), 5807 diag::note_previous_definition); 5808 Name = 0; 5809 Previous.clear(); 5810 Invalid = true; 5811 } 5812 } 5813 5814 // Okay, this is definition of a previously declared or referenced 5815 // tag PrevDecl. We're going to create a new Decl for it. 5816 } 5817 } 5818 // If we get here we have (another) forward declaration or we 5819 // have a definition. Just create a new decl. 5820 5821 } else { 5822 // If we get here, this is a definition of a new tag type in a nested 5823 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5824 // new decl/type. We set PrevDecl to NULL so that the entities 5825 // have distinct types. 5826 Previous.clear(); 5827 } 5828 // If we get here, we're going to create a new Decl. If PrevDecl 5829 // is non-NULL, it's a definition of the tag declared by 5830 // PrevDecl. If it's NULL, we have a new definition. 5831 5832 5833 // Otherwise, PrevDecl is not a tag, but was found with tag 5834 // lookup. This is only actually possible in C++, where a few 5835 // things like templates still live in the tag namespace. 5836 } else { 5837 assert(getLangOptions().CPlusPlus); 5838 5839 // Use a better diagnostic if an elaborated-type-specifier 5840 // found the wrong kind of type on the first 5841 // (non-redeclaration) lookup. 5842 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5843 !Previous.isForRedeclaration()) { 5844 unsigned Kind = 0; 5845 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5846 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5847 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5848 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5849 Invalid = true; 5850 5851 // Otherwise, only diagnose if the declaration is in scope. 5852 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5853 // do nothing 5854 5855 // Diagnose implicit declarations introduced by elaborated types. 5856 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5857 unsigned Kind = 0; 5858 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5859 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5860 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5861 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5862 Invalid = true; 5863 5864 // Otherwise it's a declaration. Call out a particularly common 5865 // case here. 5866 } else if (isa<TypedefDecl>(PrevDecl)) { 5867 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5868 << Name 5869 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5870 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5871 Invalid = true; 5872 5873 // Otherwise, diagnose. 5874 } else { 5875 // The tag name clashes with something else in the target scope, 5876 // issue an error and recover by making this tag be anonymous. 5877 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5878 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5879 Name = 0; 5880 Invalid = true; 5881 } 5882 5883 // The existing declaration isn't relevant to us; we're in a 5884 // new scope, so clear out the previous declaration. 5885 Previous.clear(); 5886 } 5887 } 5888 5889CreateNewDecl: 5890 5891 TagDecl *PrevDecl = 0; 5892 if (Previous.isSingleResult()) 5893 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5894 5895 // If there is an identifier, use the location of the identifier as the 5896 // location of the decl, otherwise use the location of the struct/union 5897 // keyword. 5898 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5899 5900 // Otherwise, create a new declaration. If there is a previous 5901 // declaration of the same entity, the two will be linked via 5902 // PrevDecl. 5903 TagDecl *New; 5904 5905 bool IsForwardReference = false; 5906 if (Kind == TTK_Enum) { 5907 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5908 // enum X { A, B, C } D; D should chain to X. 5909 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5910 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 5911 !EnumUnderlying.isNull()); 5912 // If this is an undefined enum, warn. 5913 if (TUK != TUK_Definition && !Invalid) { 5914 TagDecl *Def; 5915 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 5916 // C++0x: 7.2p2: opaque-enum-declaration. 5917 // Conflicts are diagnosed above. Do nothing. 5918 } 5919 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5920 Diag(Loc, diag::ext_forward_ref_enum_def) 5921 << New; 5922 Diag(Def->getLocation(), diag::note_previous_definition); 5923 } else { 5924 unsigned DiagID = diag::ext_forward_ref_enum; 5925 if (getLangOptions().Microsoft) 5926 DiagID = diag::ext_ms_forward_ref_enum; 5927 else if (getLangOptions().CPlusPlus) 5928 DiagID = diag::err_forward_ref_enum; 5929 Diag(Loc, DiagID); 5930 5931 // If this is a forward-declared reference to an enumeration, make a 5932 // note of it; we won't actually be introducing the declaration into 5933 // the declaration context. 5934 if (TUK == TUK_Reference) 5935 IsForwardReference = true; 5936 } 5937 } 5938 5939 if (EnumUnderlying) { 5940 EnumDecl *ED = cast<EnumDecl>(New); 5941 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5942 ED->setIntegerTypeSourceInfo(TI); 5943 else 5944 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 5945 ED->setPromotionType(ED->getIntegerType()); 5946 } 5947 5948 } else { 5949 // struct/union/class 5950 5951 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5952 // struct X { int A; } D; D should chain to X. 5953 if (getLangOptions().CPlusPlus) { 5954 // FIXME: Look for a way to use RecordDecl for simple structs. 5955 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5956 cast_or_null<CXXRecordDecl>(PrevDecl)); 5957 5958 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5959 StdBadAlloc = cast<CXXRecordDecl>(New); 5960 } else 5961 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5962 cast_or_null<RecordDecl>(PrevDecl)); 5963 } 5964 5965 // Maybe add qualifier info. 5966 if (SS.isNotEmpty()) { 5967 if (SS.isSet()) { 5968 NestedNameSpecifier *NNS 5969 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5970 New->setQualifierInfo(NNS, SS.getRange()); 5971 if (NumMatchedTemplateParamLists > 0) { 5972 New->setTemplateParameterListsInfo(Context, 5973 NumMatchedTemplateParamLists, 5974 (TemplateParameterList**) TemplateParameterLists.release()); 5975 } 5976 } 5977 else 5978 Invalid = true; 5979 } 5980 5981 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5982 // Add alignment attributes if necessary; these attributes are checked when 5983 // the ASTContext lays out the structure. 5984 // 5985 // It is important for implementing the correct semantics that this 5986 // happen here (in act on tag decl). The #pragma pack stack is 5987 // maintained as a result of parser callbacks which can occur at 5988 // many points during the parsing of a struct declaration (because 5989 // the #pragma tokens are effectively skipped over during the 5990 // parsing of the struct). 5991 AddAlignmentAttributesForRecord(RD); 5992 } 5993 5994 // If this is a specialization of a member class (of a class template), 5995 // check the specialization. 5996 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5997 Invalid = true; 5998 5999 if (Invalid) 6000 New->setInvalidDecl(); 6001 6002 if (Attr) 6003 ProcessDeclAttributeList(S, New, Attr); 6004 6005 // If we're declaring or defining a tag in function prototype scope 6006 // in C, note that this type can only be used within the function. 6007 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6008 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6009 6010 // Set the lexical context. If the tag has a C++ scope specifier, the 6011 // lexical context will be different from the semantic context. 6012 New->setLexicalDeclContext(CurContext); 6013 6014 // Mark this as a friend decl if applicable. 6015 if (TUK == TUK_Friend) 6016 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6017 6018 // Set the access specifier. 6019 if (!Invalid && SearchDC->isRecord()) 6020 SetMemberAccessSpecifier(New, PrevDecl, AS); 6021 6022 if (TUK == TUK_Definition) 6023 New->startDefinition(); 6024 6025 // If this has an identifier, add it to the scope stack. 6026 if (TUK == TUK_Friend) { 6027 // We might be replacing an existing declaration in the lookup tables; 6028 // if so, borrow its access specifier. 6029 if (PrevDecl) 6030 New->setAccess(PrevDecl->getAccess()); 6031 6032 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6033 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6034 if (Name) // can be null along some error paths 6035 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6036 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6037 } else if (Name) { 6038 S = getNonFieldDeclScope(S); 6039 PushOnScopeChains(New, S, !IsForwardReference); 6040 if (IsForwardReference) 6041 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6042 6043 } else { 6044 CurContext->addDecl(New); 6045 } 6046 6047 // If this is the C FILE type, notify the AST context. 6048 if (IdentifierInfo *II = New->getIdentifier()) 6049 if (!New->isInvalidDecl() && 6050 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6051 II->isStr("FILE")) 6052 Context.setFILEDecl(New); 6053 6054 OwnedDecl = true; 6055 return New; 6056} 6057 6058void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6059 AdjustDeclIfTemplate(TagD); 6060 TagDecl *Tag = cast<TagDecl>(TagD); 6061 6062 // Enter the tag context. 6063 PushDeclContext(S, Tag); 6064} 6065 6066void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6067 SourceLocation LBraceLoc) { 6068 AdjustDeclIfTemplate(TagD); 6069 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6070 6071 FieldCollector->StartClass(); 6072 6073 if (!Record->getIdentifier()) 6074 return; 6075 6076 // C++ [class]p2: 6077 // [...] The class-name is also inserted into the scope of the 6078 // class itself; this is known as the injected-class-name. For 6079 // purposes of access checking, the injected-class-name is treated 6080 // as if it were a public member name. 6081 CXXRecordDecl *InjectedClassName 6082 = CXXRecordDecl::Create(Context, Record->getTagKind(), 6083 CurContext, Record->getLocation(), 6084 Record->getIdentifier(), 6085 Record->getTagKeywordLoc(), 6086 /*PrevDecl=*/0, 6087 /*DelayTypeCreation=*/true); 6088 Context.getTypeDeclType(InjectedClassName, Record); 6089 InjectedClassName->setImplicit(); 6090 InjectedClassName->setAccess(AS_public); 6091 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6092 InjectedClassName->setDescribedClassTemplate(Template); 6093 PushOnScopeChains(InjectedClassName, S); 6094 assert(InjectedClassName->isInjectedClassName() && 6095 "Broken injected-class-name"); 6096} 6097 6098void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6099 SourceLocation RBraceLoc) { 6100 AdjustDeclIfTemplate(TagD); 6101 TagDecl *Tag = cast<TagDecl>(TagD); 6102 Tag->setRBraceLoc(RBraceLoc); 6103 6104 if (isa<CXXRecordDecl>(Tag)) 6105 FieldCollector->FinishClass(); 6106 6107 // Exit this scope of this tag's definition. 6108 PopDeclContext(); 6109 6110 // Notify the consumer that we've defined a tag. 6111 Consumer.HandleTagDeclDefinition(Tag); 6112} 6113 6114void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6115 AdjustDeclIfTemplate(TagD); 6116 TagDecl *Tag = cast<TagDecl>(TagD); 6117 Tag->setInvalidDecl(); 6118 6119 // We're undoing ActOnTagStartDefinition here, not 6120 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6121 // the FieldCollector. 6122 6123 PopDeclContext(); 6124} 6125 6126// Note that FieldName may be null for anonymous bitfields. 6127bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6128 QualType FieldTy, const Expr *BitWidth, 6129 bool *ZeroWidth) { 6130 // Default to true; that shouldn't confuse checks for emptiness 6131 if (ZeroWidth) 6132 *ZeroWidth = true; 6133 6134 // C99 6.7.2.1p4 - verify the field type. 6135 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6136 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6137 // Handle incomplete types with specific error. 6138 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6139 return true; 6140 if (FieldName) 6141 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6142 << FieldName << FieldTy << BitWidth->getSourceRange(); 6143 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6144 << FieldTy << BitWidth->getSourceRange(); 6145 } 6146 6147 // If the bit-width is type- or value-dependent, don't try to check 6148 // it now. 6149 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6150 return false; 6151 6152 llvm::APSInt Value; 6153 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6154 return true; 6155 6156 if (Value != 0 && ZeroWidth) 6157 *ZeroWidth = false; 6158 6159 // Zero-width bitfield is ok for anonymous field. 6160 if (Value == 0 && FieldName) 6161 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6162 6163 if (Value.isSigned() && Value.isNegative()) { 6164 if (FieldName) 6165 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6166 << FieldName << Value.toString(10); 6167 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6168 << Value.toString(10); 6169 } 6170 6171 if (!FieldTy->isDependentType()) { 6172 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6173 if (Value.getZExtValue() > TypeSize) { 6174 if (!getLangOptions().CPlusPlus) { 6175 if (FieldName) 6176 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6177 << FieldName << (unsigned)Value.getZExtValue() 6178 << (unsigned)TypeSize; 6179 6180 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6181 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6182 } 6183 6184 if (FieldName) 6185 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6186 << FieldName << (unsigned)Value.getZExtValue() 6187 << (unsigned)TypeSize; 6188 else 6189 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6190 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6191 } 6192 } 6193 6194 return false; 6195} 6196 6197/// ActOnField - Each field of a struct/union/class is passed into this in order 6198/// to create a FieldDecl object for it. 6199Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6200 SourceLocation DeclStart, 6201 Declarator &D, ExprTy *BitfieldWidth) { 6202 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6203 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6204 AS_public); 6205 return Res; 6206} 6207 6208/// HandleField - Analyze a field of a C struct or a C++ data member. 6209/// 6210FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6211 SourceLocation DeclStart, 6212 Declarator &D, Expr *BitWidth, 6213 AccessSpecifier AS) { 6214 IdentifierInfo *II = D.getIdentifier(); 6215 SourceLocation Loc = DeclStart; 6216 if (II) Loc = D.getIdentifierLoc(); 6217 6218 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6219 QualType T = TInfo->getType(); 6220 if (getLangOptions().CPlusPlus) 6221 CheckExtraCXXDefaultArguments(D); 6222 6223 DiagnoseFunctionSpecifiers(D); 6224 6225 if (D.getDeclSpec().isThreadSpecified()) 6226 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6227 6228 // Check to see if this name was declared as a member previously 6229 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6230 LookupName(Previous, S); 6231 assert((Previous.empty() || Previous.isOverloadedResult() || 6232 Previous.isSingleResult()) 6233 && "Lookup of member name should be either overloaded, single or null"); 6234 6235 // If the name is overloaded then get any declaration else get the single result 6236 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6237 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6238 6239 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6240 // Maybe we will complain about the shadowed template parameter. 6241 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6242 // Just pretend that we didn't see the previous declaration. 6243 PrevDecl = 0; 6244 } 6245 6246 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6247 PrevDecl = 0; 6248 6249 bool Mutable 6250 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6251 SourceLocation TSSL = D.getSourceRange().getBegin(); 6252 FieldDecl *NewFD 6253 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6254 AS, PrevDecl, &D); 6255 6256 if (NewFD->isInvalidDecl()) 6257 Record->setInvalidDecl(); 6258 6259 if (NewFD->isInvalidDecl() && PrevDecl) { 6260 // Don't introduce NewFD into scope; there's already something 6261 // with the same name in the same scope. 6262 } else if (II) { 6263 PushOnScopeChains(NewFD, S); 6264 } else 6265 Record->addDecl(NewFD); 6266 6267 return NewFD; 6268} 6269 6270/// \brief Build a new FieldDecl and check its well-formedness. 6271/// 6272/// This routine builds a new FieldDecl given the fields name, type, 6273/// record, etc. \p PrevDecl should refer to any previous declaration 6274/// with the same name and in the same scope as the field to be 6275/// created. 6276/// 6277/// \returns a new FieldDecl. 6278/// 6279/// \todo The Declarator argument is a hack. It will be removed once 6280FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6281 TypeSourceInfo *TInfo, 6282 RecordDecl *Record, SourceLocation Loc, 6283 bool Mutable, Expr *BitWidth, 6284 SourceLocation TSSL, 6285 AccessSpecifier AS, NamedDecl *PrevDecl, 6286 Declarator *D) { 6287 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6288 bool InvalidDecl = false; 6289 if (D) InvalidDecl = D->isInvalidType(); 6290 6291 // If we receive a broken type, recover by assuming 'int' and 6292 // marking this declaration as invalid. 6293 if (T.isNull()) { 6294 InvalidDecl = true; 6295 T = Context.IntTy; 6296 } 6297 6298 QualType EltTy = Context.getBaseElementType(T); 6299 if (!EltTy->isDependentType() && 6300 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6301 // Fields of incomplete type force their record to be invalid. 6302 Record->setInvalidDecl(); 6303 InvalidDecl = true; 6304 } 6305 6306 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6307 // than a variably modified type. 6308 if (!InvalidDecl && T->isVariablyModifiedType()) { 6309 bool SizeIsNegative; 6310 llvm::APSInt Oversized; 6311 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6312 SizeIsNegative, 6313 Oversized); 6314 if (!FixedTy.isNull()) { 6315 Diag(Loc, diag::warn_illegal_constant_array_size); 6316 T = FixedTy; 6317 } else { 6318 if (SizeIsNegative) 6319 Diag(Loc, diag::err_typecheck_negative_array_size); 6320 else if (Oversized.getBoolValue()) 6321 Diag(Loc, diag::err_array_too_large) 6322 << Oversized.toString(10); 6323 else 6324 Diag(Loc, diag::err_typecheck_field_variable_size); 6325 InvalidDecl = true; 6326 } 6327 } 6328 6329 // Fields can not have abstract class types 6330 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6331 diag::err_abstract_type_in_decl, 6332 AbstractFieldType)) 6333 InvalidDecl = true; 6334 6335 bool ZeroWidth = false; 6336 // If this is declared as a bit-field, check the bit-field. 6337 if (!InvalidDecl && BitWidth && 6338 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6339 InvalidDecl = true; 6340 BitWidth = 0; 6341 ZeroWidth = false; 6342 } 6343 6344 // Check that 'mutable' is consistent with the type of the declaration. 6345 if (!InvalidDecl && Mutable) { 6346 unsigned DiagID = 0; 6347 if (T->isReferenceType()) 6348 DiagID = diag::err_mutable_reference; 6349 else if (T.isConstQualified()) 6350 DiagID = diag::err_mutable_const; 6351 6352 if (DiagID) { 6353 SourceLocation ErrLoc = Loc; 6354 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6355 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6356 Diag(ErrLoc, DiagID); 6357 Mutable = false; 6358 InvalidDecl = true; 6359 } 6360 } 6361 6362 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6363 BitWidth, Mutable); 6364 if (InvalidDecl) 6365 NewFD->setInvalidDecl(); 6366 6367 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6368 Diag(Loc, diag::err_duplicate_member) << II; 6369 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6370 NewFD->setInvalidDecl(); 6371 } 6372 6373 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6374 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6375 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6376 if (RDecl->getDefinition()) { 6377 // C++ 9.5p1: An object of a class with a non-trivial 6378 // constructor, a non-trivial copy constructor, a non-trivial 6379 // destructor, or a non-trivial copy assignment operator 6380 // cannot be a member of a union, nor can an array of such 6381 // objects. 6382 // TODO: C++0x alters this restriction significantly. 6383 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6384 NewFD->setInvalidDecl(); 6385 } 6386 } 6387 } 6388 6389 // FIXME: We need to pass in the attributes given an AST 6390 // representation, not a parser representation. 6391 if (D) 6392 // FIXME: What to pass instead of TUScope? 6393 ProcessDeclAttributes(TUScope, NewFD, *D); 6394 6395 if (T.isObjCGCWeak()) 6396 Diag(Loc, diag::warn_attribute_weak_on_field); 6397 6398 NewFD->setAccess(AS); 6399 return NewFD; 6400} 6401 6402bool Sema::CheckNontrivialField(FieldDecl *FD) { 6403 assert(FD); 6404 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6405 6406 if (FD->isInvalidDecl()) 6407 return true; 6408 6409 QualType EltTy = Context.getBaseElementType(FD->getType()); 6410 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6411 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6412 if (RDecl->getDefinition()) { 6413 // We check for copy constructors before constructors 6414 // because otherwise we'll never get complaints about 6415 // copy constructors. 6416 6417 CXXSpecialMember member = CXXInvalid; 6418 if (!RDecl->hasTrivialCopyConstructor()) 6419 member = CXXCopyConstructor; 6420 else if (!RDecl->hasTrivialConstructor()) 6421 member = CXXConstructor; 6422 else if (!RDecl->hasTrivialCopyAssignment()) 6423 member = CXXCopyAssignment; 6424 else if (!RDecl->hasTrivialDestructor()) 6425 member = CXXDestructor; 6426 6427 if (member != CXXInvalid) { 6428 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6429 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6430 DiagnoseNontrivial(RT, member); 6431 return true; 6432 } 6433 } 6434 } 6435 6436 return false; 6437} 6438 6439/// DiagnoseNontrivial - Given that a class has a non-trivial 6440/// special member, figure out why. 6441void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6442 QualType QT(T, 0U); 6443 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6444 6445 // Check whether the member was user-declared. 6446 switch (member) { 6447 case CXXInvalid: 6448 break; 6449 6450 case CXXConstructor: 6451 if (RD->hasUserDeclaredConstructor()) { 6452 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6453 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6454 const FunctionDecl *body = 0; 6455 ci->hasBody(body); 6456 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6457 SourceLocation CtorLoc = ci->getLocation(); 6458 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6459 return; 6460 } 6461 } 6462 6463 assert(0 && "found no user-declared constructors"); 6464 return; 6465 } 6466 break; 6467 6468 case CXXCopyConstructor: 6469 if (RD->hasUserDeclaredCopyConstructor()) { 6470 SourceLocation CtorLoc = 6471 RD->getCopyConstructor(Context, 0)->getLocation(); 6472 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6473 return; 6474 } 6475 break; 6476 6477 case CXXCopyAssignment: 6478 if (RD->hasUserDeclaredCopyAssignment()) { 6479 // FIXME: this should use the location of the copy 6480 // assignment, not the type. 6481 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6482 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6483 return; 6484 } 6485 break; 6486 6487 case CXXDestructor: 6488 if (RD->hasUserDeclaredDestructor()) { 6489 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6490 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6491 return; 6492 } 6493 break; 6494 } 6495 6496 typedef CXXRecordDecl::base_class_iterator base_iter; 6497 6498 // Virtual bases and members inhibit trivial copying/construction, 6499 // but not trivial destruction. 6500 if (member != CXXDestructor) { 6501 // Check for virtual bases. vbases includes indirect virtual bases, 6502 // so we just iterate through the direct bases. 6503 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6504 if (bi->isVirtual()) { 6505 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6506 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6507 return; 6508 } 6509 6510 // Check for virtual methods. 6511 typedef CXXRecordDecl::method_iterator meth_iter; 6512 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6513 ++mi) { 6514 if (mi->isVirtual()) { 6515 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6516 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6517 return; 6518 } 6519 } 6520 } 6521 6522 bool (CXXRecordDecl::*hasTrivial)() const; 6523 switch (member) { 6524 case CXXConstructor: 6525 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6526 case CXXCopyConstructor: 6527 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6528 case CXXCopyAssignment: 6529 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6530 case CXXDestructor: 6531 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6532 default: 6533 assert(0 && "unexpected special member"); return; 6534 } 6535 6536 // Check for nontrivial bases (and recurse). 6537 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6538 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6539 assert(BaseRT && "Don't know how to handle dependent bases"); 6540 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6541 if (!(BaseRecTy->*hasTrivial)()) { 6542 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6543 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6544 DiagnoseNontrivial(BaseRT, member); 6545 return; 6546 } 6547 } 6548 6549 // Check for nontrivial members (and recurse). 6550 typedef RecordDecl::field_iterator field_iter; 6551 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6552 ++fi) { 6553 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6554 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6555 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6556 6557 if (!(EltRD->*hasTrivial)()) { 6558 SourceLocation FLoc = (*fi)->getLocation(); 6559 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6560 DiagnoseNontrivial(EltRT, member); 6561 return; 6562 } 6563 } 6564 } 6565 6566 assert(0 && "found no explanation for non-trivial member"); 6567} 6568 6569/// TranslateIvarVisibility - Translate visibility from a token ID to an 6570/// AST enum value. 6571static ObjCIvarDecl::AccessControl 6572TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6573 switch (ivarVisibility) { 6574 default: assert(0 && "Unknown visitibility kind"); 6575 case tok::objc_private: return ObjCIvarDecl::Private; 6576 case tok::objc_public: return ObjCIvarDecl::Public; 6577 case tok::objc_protected: return ObjCIvarDecl::Protected; 6578 case tok::objc_package: return ObjCIvarDecl::Package; 6579 } 6580} 6581 6582/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6583/// in order to create an IvarDecl object for it. 6584Decl *Sema::ActOnIvar(Scope *S, 6585 SourceLocation DeclStart, 6586 Decl *IntfDecl, 6587 Declarator &D, ExprTy *BitfieldWidth, 6588 tok::ObjCKeywordKind Visibility) { 6589 6590 IdentifierInfo *II = D.getIdentifier(); 6591 Expr *BitWidth = (Expr*)BitfieldWidth; 6592 SourceLocation Loc = DeclStart; 6593 if (II) Loc = D.getIdentifierLoc(); 6594 6595 // FIXME: Unnamed fields can be handled in various different ways, for 6596 // example, unnamed unions inject all members into the struct namespace! 6597 6598 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6599 QualType T = TInfo->getType(); 6600 6601 if (BitWidth) { 6602 // 6.7.2.1p3, 6.7.2.1p4 6603 if (VerifyBitField(Loc, II, T, BitWidth)) { 6604 D.setInvalidType(); 6605 BitWidth = 0; 6606 } 6607 } else { 6608 // Not a bitfield. 6609 6610 // validate II. 6611 6612 } 6613 if (T->isReferenceType()) { 6614 Diag(Loc, diag::err_ivar_reference_type); 6615 D.setInvalidType(); 6616 } 6617 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6618 // than a variably modified type. 6619 else if (T->isVariablyModifiedType()) { 6620 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6621 D.setInvalidType(); 6622 } 6623 6624 // Get the visibility (access control) for this ivar. 6625 ObjCIvarDecl::AccessControl ac = 6626 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6627 : ObjCIvarDecl::None; 6628 // Must set ivar's DeclContext to its enclosing interface. 6629 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6630 ObjCContainerDecl *EnclosingContext; 6631 if (ObjCImplementationDecl *IMPDecl = 6632 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6633 if (!LangOpts.ObjCNonFragileABI2) { 6634 // Case of ivar declared in an implementation. Context is that of its class. 6635 EnclosingContext = IMPDecl->getClassInterface(); 6636 assert(EnclosingContext && "Implementation has no class interface!"); 6637 } 6638 else 6639 EnclosingContext = EnclosingDecl; 6640 } else { 6641 if (ObjCCategoryDecl *CDecl = 6642 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6643 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6644 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6645 return 0; 6646 } 6647 } 6648 EnclosingContext = EnclosingDecl; 6649 } 6650 6651 // Construct the decl. 6652 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6653 EnclosingContext, Loc, II, T, 6654 TInfo, ac, (Expr *)BitfieldWidth); 6655 6656 if (II) { 6657 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6658 ForRedeclaration); 6659 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6660 && !isa<TagDecl>(PrevDecl)) { 6661 Diag(Loc, diag::err_duplicate_member) << II; 6662 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6663 NewID->setInvalidDecl(); 6664 } 6665 } 6666 6667 // Process attributes attached to the ivar. 6668 ProcessDeclAttributes(S, NewID, D); 6669 6670 if (D.isInvalidType()) 6671 NewID->setInvalidDecl(); 6672 6673 if (II) { 6674 // FIXME: When interfaces are DeclContexts, we'll need to add 6675 // these to the interface. 6676 S->AddDecl(NewID); 6677 IdResolver.AddDecl(NewID); 6678 } 6679 6680 return NewID; 6681} 6682 6683/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6684/// class and class extensions. For every class @interface and class 6685/// extension @interface, if the last ivar is a bitfield of any type, 6686/// then add an implicit `char :0` ivar to the end of that interface. 6687void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6688 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6689 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6690 return; 6691 6692 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6693 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6694 6695 if (!Ivar->isBitField()) 6696 return; 6697 uint64_t BitFieldSize = 6698 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6699 if (BitFieldSize == 0) 6700 return; 6701 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6702 if (!ID) { 6703 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6704 if (!CD->IsClassExtension()) 6705 return; 6706 } 6707 // No need to add this to end of @implementation. 6708 else 6709 return; 6710 } 6711 // All conditions are met. Add a new bitfield to the tail end of ivars. 6712 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6713 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6714 6715 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6716 DeclLoc, 0, 6717 Context.CharTy, 6718 Context.CreateTypeSourceInfo(Context.CharTy), 6719 ObjCIvarDecl::Private, BW, 6720 true); 6721 AllIvarDecls.push_back(Ivar); 6722} 6723 6724void Sema::ActOnFields(Scope* S, 6725 SourceLocation RecLoc, Decl *EnclosingDecl, 6726 Decl **Fields, unsigned NumFields, 6727 SourceLocation LBrac, SourceLocation RBrac, 6728 AttributeList *Attr) { 6729 assert(EnclosingDecl && "missing record or interface decl"); 6730 6731 // If the decl this is being inserted into is invalid, then it may be a 6732 // redeclaration or some other bogus case. Don't try to add fields to it. 6733 if (EnclosingDecl->isInvalidDecl()) { 6734 // FIXME: Deallocate fields? 6735 return; 6736 } 6737 6738 6739 // Verify that all the fields are okay. 6740 unsigned NumNamedMembers = 0; 6741 llvm::SmallVector<FieldDecl*, 32> RecFields; 6742 6743 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6744 for (unsigned i = 0; i != NumFields; ++i) { 6745 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6746 6747 // Get the type for the field. 6748 Type *FDTy = FD->getType().getTypePtr(); 6749 6750 if (!FD->isAnonymousStructOrUnion()) { 6751 // Remember all fields written by the user. 6752 RecFields.push_back(FD); 6753 } 6754 6755 // If the field is already invalid for some reason, don't emit more 6756 // diagnostics about it. 6757 if (FD->isInvalidDecl()) { 6758 EnclosingDecl->setInvalidDecl(); 6759 continue; 6760 } 6761 6762 // C99 6.7.2.1p2: 6763 // A structure or union shall not contain a member with 6764 // incomplete or function type (hence, a structure shall not 6765 // contain an instance of itself, but may contain a pointer to 6766 // an instance of itself), except that the last member of a 6767 // structure with more than one named member may have incomplete 6768 // array type; such a structure (and any union containing, 6769 // possibly recursively, a member that is such a structure) 6770 // shall not be a member of a structure or an element of an 6771 // array. 6772 if (FDTy->isFunctionType()) { 6773 // Field declared as a function. 6774 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6775 << FD->getDeclName(); 6776 FD->setInvalidDecl(); 6777 EnclosingDecl->setInvalidDecl(); 6778 continue; 6779 } else if (FDTy->isIncompleteArrayType() && Record && 6780 ((i == NumFields - 1 && !Record->isUnion()) || 6781 (getLangOptions().Microsoft && 6782 (i == NumFields - 1 || Record->isUnion())))) { 6783 // Flexible array member. 6784 // Microsoft is more permissive regarding flexible array. 6785 // It will accept flexible array in union and also 6786 // as the sole element of a struct/class. 6787 if (getLangOptions().Microsoft) { 6788 if (Record->isUnion()) 6789 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6790 << FD->getDeclName(); 6791 else if (NumFields == 1) 6792 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6793 << FD->getDeclName() << Record->getTagKind(); 6794 } else if (NumNamedMembers < 1) { 6795 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6796 << FD->getDeclName(); 6797 FD->setInvalidDecl(); 6798 EnclosingDecl->setInvalidDecl(); 6799 continue; 6800 } 6801 if (!FD->getType()->isDependentType() && 6802 !Context.getBaseElementType(FD->getType())->isPODType()) { 6803 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6804 << FD->getDeclName() << FD->getType(); 6805 FD->setInvalidDecl(); 6806 EnclosingDecl->setInvalidDecl(); 6807 continue; 6808 } 6809 // Okay, we have a legal flexible array member at the end of the struct. 6810 if (Record) 6811 Record->setHasFlexibleArrayMember(true); 6812 } else if (!FDTy->isDependentType() && 6813 RequireCompleteType(FD->getLocation(), FD->getType(), 6814 diag::err_field_incomplete)) { 6815 // Incomplete type 6816 FD->setInvalidDecl(); 6817 EnclosingDecl->setInvalidDecl(); 6818 continue; 6819 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6820 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6821 // If this is a member of a union, then entire union becomes "flexible". 6822 if (Record && Record->isUnion()) { 6823 Record->setHasFlexibleArrayMember(true); 6824 } else { 6825 // If this is a struct/class and this is not the last element, reject 6826 // it. Note that GCC supports variable sized arrays in the middle of 6827 // structures. 6828 if (i != NumFields-1) 6829 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6830 << FD->getDeclName() << FD->getType(); 6831 else { 6832 // We support flexible arrays at the end of structs in 6833 // other structs as an extension. 6834 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6835 << FD->getDeclName(); 6836 if (Record) 6837 Record->setHasFlexibleArrayMember(true); 6838 } 6839 } 6840 } 6841 if (Record && FDTTy->getDecl()->hasObjectMember()) 6842 Record->setHasObjectMember(true); 6843 } else if (FDTy->isObjCObjectType()) { 6844 /// A field cannot be an Objective-c object 6845 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6846 FD->setInvalidDecl(); 6847 EnclosingDecl->setInvalidDecl(); 6848 continue; 6849 } else if (getLangOptions().ObjC1 && 6850 getLangOptions().getGCMode() != LangOptions::NonGC && 6851 Record && 6852 (FD->getType()->isObjCObjectPointerType() || 6853 FD->getType().isObjCGCStrong())) 6854 Record->setHasObjectMember(true); 6855 else if (Context.getAsArrayType(FD->getType())) { 6856 QualType BaseType = Context.getBaseElementType(FD->getType()); 6857 if (Record && BaseType->isRecordType() && 6858 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6859 Record->setHasObjectMember(true); 6860 } 6861 // Keep track of the number of named members. 6862 if (FD->getIdentifier()) 6863 ++NumNamedMembers; 6864 } 6865 6866 // Okay, we successfully defined 'Record'. 6867 if (Record) { 6868 bool Completed = false; 6869 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 6870 if (!CXXRecord->isInvalidDecl()) { 6871 // Set access bits correctly on the directly-declared conversions. 6872 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 6873 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 6874 I != E; ++I) 6875 Convs->setAccess(I, (*I)->getAccess()); 6876 6877 if (!CXXRecord->isDependentType()) { 6878 // Add any implicitly-declared members to this class. 6879 AddImplicitlyDeclaredMembersToClass(CXXRecord); 6880 6881 // If we have virtual base classes, we may end up finding multiple 6882 // final overriders for a given virtual function. Check for this 6883 // problem now. 6884 if (CXXRecord->getNumVBases()) { 6885 CXXFinalOverriderMap FinalOverriders; 6886 CXXRecord->getFinalOverriders(FinalOverriders); 6887 6888 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 6889 MEnd = FinalOverriders.end(); 6890 M != MEnd; ++M) { 6891 for (OverridingMethods::iterator SO = M->second.begin(), 6892 SOEnd = M->second.end(); 6893 SO != SOEnd; ++SO) { 6894 assert(SO->second.size() > 0 && 6895 "Virtual function without overridding functions?"); 6896 if (SO->second.size() == 1) 6897 continue; 6898 6899 // C++ [class.virtual]p2: 6900 // In a derived class, if a virtual member function of a base 6901 // class subobject has more than one final overrider the 6902 // program is ill-formed. 6903 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 6904 << (NamedDecl *)M->first << Record; 6905 Diag(M->first->getLocation(), 6906 diag::note_overridden_virtual_function); 6907 for (OverridingMethods::overriding_iterator 6908 OM = SO->second.begin(), 6909 OMEnd = SO->second.end(); 6910 OM != OMEnd; ++OM) 6911 Diag(OM->Method->getLocation(), diag::note_final_overrider) 6912 << (NamedDecl *)M->first << OM->Method->getParent(); 6913 6914 Record->setInvalidDecl(); 6915 } 6916 } 6917 CXXRecord->completeDefinition(&FinalOverriders); 6918 Completed = true; 6919 } 6920 } 6921 } 6922 } 6923 6924 if (!Completed) 6925 Record->completeDefinition(); 6926 } else { 6927 ObjCIvarDecl **ClsFields = 6928 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6929 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6930 ID->setLocEnd(RBrac); 6931 // Add ivar's to class's DeclContext. 6932 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6933 ClsFields[i]->setLexicalDeclContext(ID); 6934 ID->addDecl(ClsFields[i]); 6935 } 6936 // Must enforce the rule that ivars in the base classes may not be 6937 // duplicates. 6938 if (ID->getSuperClass()) 6939 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6940 } else if (ObjCImplementationDecl *IMPDecl = 6941 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6942 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6943 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6944 // Ivar declared in @implementation never belongs to the implementation. 6945 // Only it is in implementation's lexical context. 6946 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6947 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6948 } else if (ObjCCategoryDecl *CDecl = 6949 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6950 // case of ivars in class extension; all other cases have been 6951 // reported as errors elsewhere. 6952 // FIXME. Class extension does not have a LocEnd field. 6953 // CDecl->setLocEnd(RBrac); 6954 // Add ivar's to class extension's DeclContext. 6955 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6956 ClsFields[i]->setLexicalDeclContext(CDecl); 6957 CDecl->addDecl(ClsFields[i]); 6958 } 6959 } 6960 } 6961 6962 if (Attr) 6963 ProcessDeclAttributeList(S, Record, Attr); 6964 6965 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6966 // set the visibility of this record. 6967 if (Record && !Record->getDeclContext()->isRecord()) 6968 AddPushedVisibilityAttribute(Record); 6969} 6970 6971/// \brief Determine whether the given integral value is representable within 6972/// the given type T. 6973static bool isRepresentableIntegerValue(ASTContext &Context, 6974 llvm::APSInt &Value, 6975 QualType T) { 6976 assert(T->isIntegralType(Context) && "Integral type required!"); 6977 unsigned BitWidth = Context.getIntWidth(T); 6978 6979 if (Value.isUnsigned() || Value.isNonNegative()) { 6980 if (T->isSignedIntegerType()) 6981 --BitWidth; 6982 return Value.getActiveBits() <= BitWidth; 6983 } 6984 return Value.getMinSignedBits() <= BitWidth; 6985} 6986 6987// \brief Given an integral type, return the next larger integral type 6988// (or a NULL type of no such type exists). 6989static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6990 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6991 // enum checking below. 6992 assert(T->isIntegralType(Context) && "Integral type required!"); 6993 const unsigned NumTypes = 4; 6994 QualType SignedIntegralTypes[NumTypes] = { 6995 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6996 }; 6997 QualType UnsignedIntegralTypes[NumTypes] = { 6998 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6999 Context.UnsignedLongLongTy 7000 }; 7001 7002 unsigned BitWidth = Context.getTypeSize(T); 7003 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7004 : UnsignedIntegralTypes; 7005 for (unsigned I = 0; I != NumTypes; ++I) 7006 if (Context.getTypeSize(Types[I]) > BitWidth) 7007 return Types[I]; 7008 7009 return QualType(); 7010} 7011 7012EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7013 EnumConstantDecl *LastEnumConst, 7014 SourceLocation IdLoc, 7015 IdentifierInfo *Id, 7016 Expr *Val) { 7017 unsigned IntWidth = Context.Target.getIntWidth(); 7018 llvm::APSInt EnumVal(IntWidth); 7019 QualType EltTy; 7020 if (Val) { 7021 if (Enum->isDependentType() || Val->isTypeDependent()) 7022 EltTy = Context.DependentTy; 7023 else { 7024 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7025 SourceLocation ExpLoc; 7026 if (!Val->isValueDependent() && 7027 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7028 Val = 0; 7029 } else { 7030 if (!getLangOptions().CPlusPlus) { 7031 // C99 6.7.2.2p2: 7032 // The expression that defines the value of an enumeration constant 7033 // shall be an integer constant expression that has a value 7034 // representable as an int. 7035 7036 // Complain if the value is not representable in an int. 7037 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7038 Diag(IdLoc, diag::ext_enum_value_not_int) 7039 << EnumVal.toString(10) << Val->getSourceRange() 7040 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7041 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7042 // Force the type of the expression to 'int'. 7043 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 7044 } 7045 } 7046 7047 if (Enum->isFixed()) { 7048 EltTy = Enum->getIntegerType(); 7049 7050 // C++0x [dcl.enum]p5: 7051 // ... if the initializing value of an enumerator cannot be 7052 // represented by the underlying type, the program is ill-formed. 7053 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) 7054 Diag(IdLoc, diag::err_enumerator_too_large) 7055 << EltTy; 7056 else 7057 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7058 } 7059 else { 7060 // C++0x [dcl.enum]p5: 7061 // If the underlying type is not fixed, the type of each enumerator 7062 // is the type of its initializing value: 7063 // - If an initializer is specified for an enumerator, the 7064 // initializing value has the same type as the expression. 7065 EltTy = Val->getType(); 7066 } 7067 } 7068 } 7069 } 7070 7071 if (!Val) { 7072 if (Enum->isDependentType()) 7073 EltTy = Context.DependentTy; 7074 else if (!LastEnumConst) { 7075 // C++0x [dcl.enum]p5: 7076 // If the underlying type is not fixed, the type of each enumerator 7077 // is the type of its initializing value: 7078 // - If no initializer is specified for the first enumerator, the 7079 // initializing value has an unspecified integral type. 7080 // 7081 // GCC uses 'int' for its unspecified integral type, as does 7082 // C99 6.7.2.2p3. 7083 if (Enum->isFixed()) { 7084 EltTy = Enum->getIntegerType(); 7085 } 7086 else { 7087 EltTy = Context.IntTy; 7088 } 7089 } else { 7090 // Assign the last value + 1. 7091 EnumVal = LastEnumConst->getInitVal(); 7092 ++EnumVal; 7093 EltTy = LastEnumConst->getType(); 7094 7095 // Check for overflow on increment. 7096 if (EnumVal < LastEnumConst->getInitVal()) { 7097 // C++0x [dcl.enum]p5: 7098 // If the underlying type is not fixed, the type of each enumerator 7099 // is the type of its initializing value: 7100 // 7101 // - Otherwise the type of the initializing value is the same as 7102 // the type of the initializing value of the preceding enumerator 7103 // unless the incremented value is not representable in that type, 7104 // in which case the type is an unspecified integral type 7105 // sufficient to contain the incremented value. If no such type 7106 // exists, the program is ill-formed. 7107 QualType T = getNextLargerIntegralType(Context, EltTy); 7108 if (T.isNull() || Enum->isFixed()) { 7109 // There is no integral type larger enough to represent this 7110 // value. Complain, then allow the value to wrap around. 7111 EnumVal = LastEnumConst->getInitVal(); 7112 EnumVal.zext(EnumVal.getBitWidth() * 2); 7113 ++EnumVal; 7114 if (Enum->isFixed()) 7115 // When the underlying type is fixed, this is ill-formed. 7116 Diag(IdLoc, diag::err_enumerator_wrapped) 7117 << EnumVal.toString(10) 7118 << EltTy; 7119 else 7120 Diag(IdLoc, diag::warn_enumerator_too_large) 7121 << EnumVal.toString(10); 7122 } else { 7123 EltTy = T; 7124 } 7125 7126 // Retrieve the last enumerator's value, extent that type to the 7127 // type that is supposed to be large enough to represent the incremented 7128 // value, then increment. 7129 EnumVal = LastEnumConst->getInitVal(); 7130 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7131 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7132 ++EnumVal; 7133 7134 // If we're not in C++, diagnose the overflow of enumerator values, 7135 // which in C99 means that the enumerator value is not representable in 7136 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7137 // permits enumerator values that are representable in some larger 7138 // integral type. 7139 if (!getLangOptions().CPlusPlus && !T.isNull()) 7140 Diag(IdLoc, diag::warn_enum_value_overflow); 7141 } else if (!getLangOptions().CPlusPlus && 7142 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7143 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7144 Diag(IdLoc, diag::ext_enum_value_not_int) 7145 << EnumVal.toString(10) << 1; 7146 } 7147 } 7148 } 7149 7150 if (!EltTy->isDependentType()) { 7151 // Make the enumerator value match the signedness and size of the 7152 // enumerator's type. 7153 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7154 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7155 } 7156 7157 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7158 Val, EnumVal); 7159} 7160 7161 7162Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 7163 Decl *lastEnumConst, 7164 SourceLocation IdLoc, 7165 IdentifierInfo *Id, 7166 SourceLocation EqualLoc, ExprTy *val) { 7167 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7168 EnumConstantDecl *LastEnumConst = 7169 cast_or_null<EnumConstantDecl>(lastEnumConst); 7170 Expr *Val = static_cast<Expr*>(val); 7171 7172 // The scope passed in may not be a decl scope. Zip up the scope tree until 7173 // we find one that is. 7174 S = getNonFieldDeclScope(S); 7175 7176 // Verify that there isn't already something declared with this name in this 7177 // scope. 7178 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7179 ForRedeclaration); 7180 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7181 // Maybe we will complain about the shadowed template parameter. 7182 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7183 // Just pretend that we didn't see the previous declaration. 7184 PrevDecl = 0; 7185 } 7186 7187 if (PrevDecl) { 7188 // When in C++, we may get a TagDecl with the same name; in this case the 7189 // enum constant will 'hide' the tag. 7190 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7191 "Received TagDecl when not in C++!"); 7192 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7193 if (isa<EnumConstantDecl>(PrevDecl)) 7194 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7195 else 7196 Diag(IdLoc, diag::err_redefinition) << Id; 7197 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7198 return 0; 7199 } 7200 } 7201 7202 // C++ [class.mem]p13: 7203 // If T is the name of a class, then each of the following shall have a 7204 // name different from T: 7205 // - every enumerator of every member of class T that is an enumerated 7206 // type 7207 if (CXXRecordDecl *Record 7208 = dyn_cast<CXXRecordDecl>( 7209 TheEnumDecl->getDeclContext()->getRedeclContext())) 7210 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7211 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7212 7213 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 7214 IdLoc, Id, Val); 7215 7216 // Register this decl in the current scope stack. 7217 if (New) { 7218 New->setAccess(TheEnumDecl->getAccess()); 7219 PushOnScopeChains(New, S); 7220 } 7221 7222 return New; 7223} 7224 7225void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7226 SourceLocation RBraceLoc, Decl *EnumDeclX, 7227 Decl **Elements, unsigned NumElements, 7228 Scope *S, AttributeList *Attr) { 7229 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7230 QualType EnumType = Context.getTypeDeclType(Enum); 7231 7232 if (Attr) 7233 ProcessDeclAttributeList(S, Enum, Attr); 7234 7235 if (Enum->isDependentType()) { 7236 for (unsigned i = 0; i != NumElements; ++i) { 7237 EnumConstantDecl *ECD = 7238 cast_or_null<EnumConstantDecl>(Elements[i]); 7239 if (!ECD) continue; 7240 7241 ECD->setType(EnumType); 7242 } 7243 7244 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7245 return; 7246 } 7247 7248 // TODO: If the result value doesn't fit in an int, it must be a long or long 7249 // long value. ISO C does not support this, but GCC does as an extension, 7250 // emit a warning. 7251 unsigned IntWidth = Context.Target.getIntWidth(); 7252 unsigned CharWidth = Context.Target.getCharWidth(); 7253 unsigned ShortWidth = Context.Target.getShortWidth(); 7254 7255 // Verify that all the values are okay, compute the size of the values, and 7256 // reverse the list. 7257 unsigned NumNegativeBits = 0; 7258 unsigned NumPositiveBits = 0; 7259 7260 // Keep track of whether all elements have type int. 7261 bool AllElementsInt = true; 7262 7263 for (unsigned i = 0; i != NumElements; ++i) { 7264 EnumConstantDecl *ECD = 7265 cast_or_null<EnumConstantDecl>(Elements[i]); 7266 if (!ECD) continue; // Already issued a diagnostic. 7267 7268 const llvm::APSInt &InitVal = ECD->getInitVal(); 7269 7270 // Keep track of the size of positive and negative values. 7271 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7272 NumPositiveBits = std::max(NumPositiveBits, 7273 (unsigned)InitVal.getActiveBits()); 7274 else 7275 NumNegativeBits = std::max(NumNegativeBits, 7276 (unsigned)InitVal.getMinSignedBits()); 7277 7278 // Keep track of whether every enum element has type int (very commmon). 7279 if (AllElementsInt) 7280 AllElementsInt = ECD->getType() == Context.IntTy; 7281 } 7282 7283 // Figure out the type that should be used for this enum. 7284 // FIXME: Support -fshort-enums. 7285 QualType BestType; 7286 unsigned BestWidth; 7287 7288 // C++0x N3000 [conv.prom]p3: 7289 // An rvalue of an unscoped enumeration type whose underlying 7290 // type is not fixed can be converted to an rvalue of the first 7291 // of the following types that can represent all the values of 7292 // the enumeration: int, unsigned int, long int, unsigned long 7293 // int, long long int, or unsigned long long int. 7294 // C99 6.4.4.3p2: 7295 // An identifier declared as an enumeration constant has type int. 7296 // The C99 rule is modified by a gcc extension 7297 QualType BestPromotionType; 7298 7299 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7300 // -fshort-enums is the equivalent to specifying the packed attribute on all 7301 // enum definitions. 7302 if (LangOpts.ShortEnums) 7303 Packed = true; 7304 7305 if (Enum->isFixed()) { 7306 BestType = BestPromotionType = Enum->getIntegerType(); 7307 // We don't need to set BestWidth, because BestType is going to be the type 7308 // of the enumerators, but we do anyway because otherwise some compilers 7309 // warn that it might be used uninitialized. 7310 BestWidth = CharWidth; 7311 } 7312 else if (NumNegativeBits) { 7313 // If there is a negative value, figure out the smallest integer type (of 7314 // int/long/longlong) that fits. 7315 // If it's packed, check also if it fits a char or a short. 7316 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7317 BestType = Context.SignedCharTy; 7318 BestWidth = CharWidth; 7319 } else if (Packed && NumNegativeBits <= ShortWidth && 7320 NumPositiveBits < ShortWidth) { 7321 BestType = Context.ShortTy; 7322 BestWidth = ShortWidth; 7323 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7324 BestType = Context.IntTy; 7325 BestWidth = IntWidth; 7326 } else { 7327 BestWidth = Context.Target.getLongWidth(); 7328 7329 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7330 BestType = Context.LongTy; 7331 } else { 7332 BestWidth = Context.Target.getLongLongWidth(); 7333 7334 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7335 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7336 BestType = Context.LongLongTy; 7337 } 7338 } 7339 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7340 } else { 7341 // If there is no negative value, figure out the smallest type that fits 7342 // all of the enumerator values. 7343 // If it's packed, check also if it fits a char or a short. 7344 if (Packed && NumPositiveBits <= CharWidth) { 7345 BestType = Context.UnsignedCharTy; 7346 BestPromotionType = Context.IntTy; 7347 BestWidth = CharWidth; 7348 } else if (Packed && NumPositiveBits <= ShortWidth) { 7349 BestType = Context.UnsignedShortTy; 7350 BestPromotionType = Context.IntTy; 7351 BestWidth = ShortWidth; 7352 } else if (NumPositiveBits <= IntWidth) { 7353 BestType = Context.UnsignedIntTy; 7354 BestWidth = IntWidth; 7355 BestPromotionType 7356 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7357 ? Context.UnsignedIntTy : Context.IntTy; 7358 } else if (NumPositiveBits <= 7359 (BestWidth = Context.Target.getLongWidth())) { 7360 BestType = Context.UnsignedLongTy; 7361 BestPromotionType 7362 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7363 ? Context.UnsignedLongTy : Context.LongTy; 7364 } else { 7365 BestWidth = Context.Target.getLongLongWidth(); 7366 assert(NumPositiveBits <= BestWidth && 7367 "How could an initializer get larger than ULL?"); 7368 BestType = Context.UnsignedLongLongTy; 7369 BestPromotionType 7370 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7371 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7372 } 7373 } 7374 7375 // Loop over all of the enumerator constants, changing their types to match 7376 // the type of the enum if needed. 7377 for (unsigned i = 0; i != NumElements; ++i) { 7378 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7379 if (!ECD) continue; // Already issued a diagnostic. 7380 7381 // Standard C says the enumerators have int type, but we allow, as an 7382 // extension, the enumerators to be larger than int size. If each 7383 // enumerator value fits in an int, type it as an int, otherwise type it the 7384 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7385 // that X has type 'int', not 'unsigned'. 7386 7387 // Determine whether the value fits into an int. 7388 llvm::APSInt InitVal = ECD->getInitVal(); 7389 7390 // If it fits into an integer type, force it. Otherwise force it to match 7391 // the enum decl type. 7392 QualType NewTy; 7393 unsigned NewWidth; 7394 bool NewSign; 7395 if (!getLangOptions().CPlusPlus && 7396 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7397 NewTy = Context.IntTy; 7398 NewWidth = IntWidth; 7399 NewSign = true; 7400 } else if (ECD->getType() == BestType) { 7401 // Already the right type! 7402 if (getLangOptions().CPlusPlus) 7403 // C++ [dcl.enum]p4: Following the closing brace of an 7404 // enum-specifier, each enumerator has the type of its 7405 // enumeration. 7406 ECD->setType(EnumType); 7407 continue; 7408 } else { 7409 NewTy = BestType; 7410 NewWidth = BestWidth; 7411 NewSign = BestType->isSignedIntegerType(); 7412 } 7413 7414 // Adjust the APSInt value. 7415 InitVal.extOrTrunc(NewWidth); 7416 InitVal.setIsSigned(NewSign); 7417 ECD->setInitVal(InitVal); 7418 7419 // Adjust the Expr initializer and type. 7420 if (ECD->getInitExpr()) 7421 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7422 CK_IntegralCast, 7423 ECD->getInitExpr(), 7424 /*base paths*/ 0, 7425 VK_RValue)); 7426 if (getLangOptions().CPlusPlus) 7427 // C++ [dcl.enum]p4: Following the closing brace of an 7428 // enum-specifier, each enumerator has the type of its 7429 // enumeration. 7430 ECD->setType(EnumType); 7431 else 7432 ECD->setType(NewTy); 7433 } 7434 7435 Enum->completeDefinition(BestType, BestPromotionType, 7436 NumPositiveBits, NumNegativeBits); 7437} 7438 7439Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7440 StringLiteral *AsmString = cast<StringLiteral>(expr); 7441 7442 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7443 Loc, AsmString); 7444 CurContext->addDecl(New); 7445 return New; 7446} 7447 7448void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7449 SourceLocation PragmaLoc, 7450 SourceLocation NameLoc) { 7451 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7452 7453 if (PrevDecl) { 7454 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7455 } else { 7456 (void)WeakUndeclaredIdentifiers.insert( 7457 std::pair<IdentifierInfo*,WeakInfo> 7458 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7459 } 7460} 7461 7462void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7463 IdentifierInfo* AliasName, 7464 SourceLocation PragmaLoc, 7465 SourceLocation NameLoc, 7466 SourceLocation AliasNameLoc) { 7467 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7468 LookupOrdinaryName); 7469 WeakInfo W = WeakInfo(Name, NameLoc); 7470 7471 if (PrevDecl) { 7472 if (!PrevDecl->hasAttr<AliasAttr>()) 7473 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7474 DeclApplyPragmaWeak(TUScope, ND, W); 7475 } else { 7476 (void)WeakUndeclaredIdentifiers.insert( 7477 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7478 } 7479} 7480