SemaDecl.cpp revision ca0408fb49c1370430672acf2d770b7151cf71de
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/Sema.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Sema/DeclSpec.h" 25#include "clang/Sema/ParsedTemplate.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(Decl *D) { 42 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 43 return DN->getQualifiedNameAsString(); 44 return ""; 45} 46 47Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 48 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 49} 50 51/// \brief If the identifier refers to a type name within this scope, 52/// return the declaration of that type. 53/// 54/// This routine performs ordinary name lookup of the identifier II 55/// within the given scope, with optional C++ scope specifier SS, to 56/// determine whether the name refers to a type. If so, returns an 57/// opaque pointer (actually a QualType) corresponding to that 58/// type. Otherwise, returns NULL. 59/// 60/// If name lookup results in an ambiguity, this routine will complain 61/// and then return NULL. 62Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, CXXScopeSpec *SS, 64 bool isClassName, 65 TypeTy *ObjectTypePtr) { 66 // Determine where we will perform name lookup. 67 DeclContext *LookupCtx = 0; 68 if (ObjectTypePtr) { 69 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 70 if (ObjectType->isRecordType()) 71 LookupCtx = computeDeclContext(ObjectType); 72 } else if (SS && SS->isNotEmpty()) { 73 LookupCtx = computeDeclContext(*SS, false); 74 75 if (!LookupCtx) { 76 if (isDependentScopeSpecifier(*SS)) { 77 // C++ [temp.res]p3: 78 // A qualified-id that refers to a type and in which the 79 // nested-name-specifier depends on a template-parameter (14.6.2) 80 // shall be prefixed by the keyword typename to indicate that the 81 // qualified-id denotes a type, forming an 82 // elaborated-type-specifier (7.1.5.3). 83 // 84 // We therefore do not perform any name lookup if the result would 85 // refer to a member of an unknown specialization. 86 if (!isClassName) 87 return 0; 88 89 // We know from the grammar that this name refers to a type, 90 // so build a dependent node to describe the type. 91 return CheckTypenameType(ETK_None, 92 (NestedNameSpecifier *)SS->getScopeRep(), II, 93 SourceLocation(), SS->getRange(), NameLoc 94 ).getAsOpaquePtr(); 95 } 96 97 return 0; 98 } 99 100 if (!LookupCtx->isDependentContext() && 101 RequireCompleteDeclContext(*SS, LookupCtx)) 102 return 0; 103 } 104 105 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 106 // lookup for class-names. 107 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 108 LookupOrdinaryName; 109 LookupResult Result(*this, &II, NameLoc, Kind); 110 if (LookupCtx) { 111 // Perform "qualified" name lookup into the declaration context we 112 // computed, which is either the type of the base of a member access 113 // expression or the declaration context associated with a prior 114 // nested-name-specifier. 115 LookupQualifiedName(Result, LookupCtx); 116 117 if (ObjectTypePtr && Result.empty()) { 118 // C++ [basic.lookup.classref]p3: 119 // If the unqualified-id is ~type-name, the type-name is looked up 120 // in the context of the entire postfix-expression. If the type T of 121 // the object expression is of a class type C, the type-name is also 122 // looked up in the scope of class C. At least one of the lookups shall 123 // find a name that refers to (possibly cv-qualified) T. 124 LookupName(Result, S); 125 } 126 } else { 127 // Perform unqualified name lookup. 128 LookupName(Result, S); 129 } 130 131 NamedDecl *IIDecl = 0; 132 switch (Result.getResultKind()) { 133 case LookupResult::NotFound: 134 case LookupResult::NotFoundInCurrentInstantiation: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 Result.suppressDiagnostics(); 138 return 0; 139 140 case LookupResult::Ambiguous: 141 // Recover from type-hiding ambiguities by hiding the type. We'll 142 // do the lookup again when looking for an object, and we can 143 // diagnose the error then. If we don't do this, then the error 144 // about hiding the type will be immediately followed by an error 145 // that only makes sense if the identifier was treated like a type. 146 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 147 Result.suppressDiagnostics(); 148 return 0; 149 } 150 151 // Look to see if we have a type anywhere in the list of results. 152 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 153 Res != ResEnd; ++Res) { 154 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 155 if (!IIDecl || 156 (*Res)->getLocation().getRawEncoding() < 157 IIDecl->getLocation().getRawEncoding()) 158 IIDecl = *Res; 159 } 160 } 161 162 if (!IIDecl) { 163 // None of the entities we found is a type, so there is no way 164 // to even assume that the result is a type. In this case, don't 165 // complain about the ambiguity. The parser will either try to 166 // perform this lookup again (e.g., as an object name), which 167 // will produce the ambiguity, or will complain that it expected 168 // a type name. 169 Result.suppressDiagnostics(); 170 return 0; 171 } 172 173 // We found a type within the ambiguous lookup; diagnose the 174 // ambiguity and then return that type. This might be the right 175 // answer, or it might not be, but it suppresses any attempt to 176 // perform the name lookup again. 177 break; 178 179 case LookupResult::Found: 180 IIDecl = Result.getFoundDecl(); 181 break; 182 } 183 184 assert(IIDecl && "Didn't find decl"); 185 186 QualType T; 187 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 188 DiagnoseUseOfDecl(IIDecl, NameLoc); 189 190 if (T.isNull()) 191 T = Context.getTypeDeclType(TD); 192 193 if (SS) 194 T = getElaboratedType(ETK_None, *SS, T); 195 196 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 197 T = Context.getObjCInterfaceType(IDecl); 198 } else { 199 // If it's not plausibly a type, suppress diagnostics. 200 Result.suppressDiagnostics(); 201 return 0; 202 } 203 204 return T.getAsOpaquePtr(); 205} 206 207/// isTagName() - This method is called *for error recovery purposes only* 208/// to determine if the specified name is a valid tag name ("struct foo"). If 209/// so, this returns the TST for the tag corresponding to it (TST_enum, 210/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 211/// where the user forgot to specify the tag. 212DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 213 // Do a tag name lookup in this scope. 214 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 215 LookupName(R, S, false); 216 R.suppressDiagnostics(); 217 if (R.getResultKind() == LookupResult::Found) 218 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 219 switch (TD->getTagKind()) { 220 default: return DeclSpec::TST_unspecified; 221 case TTK_Struct: return DeclSpec::TST_struct; 222 case TTK_Union: return DeclSpec::TST_union; 223 case TTK_Class: return DeclSpec::TST_class; 224 case TTK_Enum: return DeclSpec::TST_enum; 225 } 226 } 227 228 return DeclSpec::TST_unspecified; 229} 230 231bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 232 SourceLocation IILoc, 233 Scope *S, 234 CXXScopeSpec *SS, 235 TypeTy *&SuggestedType) { 236 // We don't have anything to suggest (yet). 237 SuggestedType = 0; 238 239 // There may have been a typo in the name of the type. Look up typo 240 // results, in case we have something that we can suggest. 241 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 242 NotForRedeclaration); 243 244 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 245 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 246 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 247 !Result->isInvalidDecl()) { 248 // We found a similarly-named type or interface; suggest that. 249 if (!SS || !SS->isSet()) 250 Diag(IILoc, diag::err_unknown_typename_suggest) 251 << &II << Lookup.getLookupName() 252 << FixItHint::CreateReplacement(SourceRange(IILoc), 253 Result->getNameAsString()); 254 else if (DeclContext *DC = computeDeclContext(*SS, false)) 255 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 256 << &II << DC << Lookup.getLookupName() << SS->getRange() 257 << FixItHint::CreateReplacement(SourceRange(IILoc), 258 Result->getNameAsString()); 259 else 260 llvm_unreachable("could not have corrected a typo here"); 261 262 Diag(Result->getLocation(), diag::note_previous_decl) 263 << Result->getDeclName(); 264 265 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 266 return true; 267 } 268 } else if (Lookup.empty()) { 269 // We corrected to a keyword. 270 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 271 Diag(IILoc, diag::err_unknown_typename_suggest) 272 << &II << Corrected; 273 return true; 274 } 275 } 276 277 if (getLangOptions().CPlusPlus) { 278 // See if II is a class template that the user forgot to pass arguments to. 279 UnqualifiedId Name; 280 Name.setIdentifier(&II, IILoc); 281 CXXScopeSpec EmptySS; 282 TemplateTy TemplateResult; 283 bool MemberOfUnknownSpecialization; 284 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 285 Name, 0, true, TemplateResult, 286 MemberOfUnknownSpecialization) == TNK_Type_template) { 287 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 288 Diag(IILoc, diag::err_template_missing_args) << TplName; 289 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 290 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 291 << TplDecl->getTemplateParameters()->getSourceRange(); 292 } 293 return true; 294 } 295 } 296 297 // FIXME: Should we move the logic that tries to recover from a missing tag 298 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 299 300 if (!SS || (!SS->isSet() && !SS->isInvalid())) 301 Diag(IILoc, diag::err_unknown_typename) << &II; 302 else if (DeclContext *DC = computeDeclContext(*SS, false)) 303 Diag(IILoc, diag::err_typename_nested_not_found) 304 << &II << DC << SS->getRange(); 305 else if (isDependentScopeSpecifier(*SS)) { 306 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 307 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 308 << SourceRange(SS->getRange().getBegin(), IILoc) 309 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 310 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 311 } else { 312 assert(SS && SS->isInvalid() && 313 "Invalid scope specifier has already been diagnosed"); 314 } 315 316 return true; 317} 318 319// Determines the context to return to after temporarily entering a 320// context. This depends in an unnecessarily complicated way on the 321// exact ordering of callbacks from the parser. 322DeclContext *Sema::getContainingDC(DeclContext *DC) { 323 324 // Functions defined inline within classes aren't parsed until we've 325 // finished parsing the top-level class, so the top-level class is 326 // the context we'll need to return to. 327 if (isa<FunctionDecl>(DC)) { 328 DC = DC->getLexicalParent(); 329 330 // A function not defined within a class will always return to its 331 // lexical context. 332 if (!isa<CXXRecordDecl>(DC)) 333 return DC; 334 335 // A C++ inline method/friend is parsed *after* the topmost class 336 // it was declared in is fully parsed ("complete"); the topmost 337 // class is the context we need to return to. 338 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 339 DC = RD; 340 341 // Return the declaration context of the topmost class the inline method is 342 // declared in. 343 return DC; 344 } 345 346 // ObjCMethodDecls are parsed (for some reason) outside the context 347 // of the class. 348 if (isa<ObjCMethodDecl>(DC)) 349 return DC->getLexicalParent()->getLexicalParent(); 350 351 return DC->getLexicalParent(); 352} 353 354void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 355 assert(getContainingDC(DC) == CurContext && 356 "The next DeclContext should be lexically contained in the current one."); 357 CurContext = DC; 358 S->setEntity(DC); 359} 360 361void Sema::PopDeclContext() { 362 assert(CurContext && "DeclContext imbalance!"); 363 364 CurContext = getContainingDC(CurContext); 365 assert(CurContext && "Popped translation unit!"); 366} 367 368/// EnterDeclaratorContext - Used when we must lookup names in the context 369/// of a declarator's nested name specifier. 370/// 371void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 372 // C++0x [basic.lookup.unqual]p13: 373 // A name used in the definition of a static data member of class 374 // X (after the qualified-id of the static member) is looked up as 375 // if the name was used in a member function of X. 376 // C++0x [basic.lookup.unqual]p14: 377 // If a variable member of a namespace is defined outside of the 378 // scope of its namespace then any name used in the definition of 379 // the variable member (after the declarator-id) is looked up as 380 // if the definition of the variable member occurred in its 381 // namespace. 382 // Both of these imply that we should push a scope whose context 383 // is the semantic context of the declaration. We can't use 384 // PushDeclContext here because that context is not necessarily 385 // lexically contained in the current context. Fortunately, 386 // the containing scope should have the appropriate information. 387 388 assert(!S->getEntity() && "scope already has entity"); 389 390#ifndef NDEBUG 391 Scope *Ancestor = S->getParent(); 392 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 393 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 394#endif 395 396 CurContext = DC; 397 S->setEntity(DC); 398} 399 400void Sema::ExitDeclaratorContext(Scope *S) { 401 assert(S->getEntity() == CurContext && "Context imbalance!"); 402 403 // Switch back to the lexical context. The safety of this is 404 // enforced by an assert in EnterDeclaratorContext. 405 Scope *Ancestor = S->getParent(); 406 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 407 CurContext = (DeclContext*) Ancestor->getEntity(); 408 409 // We don't need to do anything with the scope, which is going to 410 // disappear. 411} 412 413/// \brief Determine whether we allow overloading of the function 414/// PrevDecl with another declaration. 415/// 416/// This routine determines whether overloading is possible, not 417/// whether some new function is actually an overload. It will return 418/// true in C++ (where we can always provide overloads) or, as an 419/// extension, in C when the previous function is already an 420/// overloaded function declaration or has the "overloadable" 421/// attribute. 422static bool AllowOverloadingOfFunction(LookupResult &Previous, 423 ASTContext &Context) { 424 if (Context.getLangOptions().CPlusPlus) 425 return true; 426 427 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 428 return true; 429 430 return (Previous.getResultKind() == LookupResult::Found 431 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 432} 433 434/// Add this decl to the scope shadowed decl chains. 435void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 436 // Move up the scope chain until we find the nearest enclosing 437 // non-transparent context. The declaration will be introduced into this 438 // scope. 439 while (S->getEntity() && 440 ((DeclContext *)S->getEntity())->isTransparentContext()) 441 S = S->getParent(); 442 443 // Add scoped declarations into their context, so that they can be 444 // found later. Declarations without a context won't be inserted 445 // into any context. 446 if (AddToContext) 447 CurContext->addDecl(D); 448 449 // Out-of-line definitions shouldn't be pushed into scope in C++. 450 // Out-of-line variable and function definitions shouldn't even in C. 451 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 452 D->isOutOfLine()) 453 return; 454 455 // Template instantiations should also not be pushed into scope. 456 if (isa<FunctionDecl>(D) && 457 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 458 return; 459 460 // If this replaces anything in the current scope, 461 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 462 IEnd = IdResolver.end(); 463 for (; I != IEnd; ++I) { 464 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 465 S->RemoveDecl(*I); 466 IdResolver.RemoveDecl(*I); 467 468 // Should only need to replace one decl. 469 break; 470 } 471 } 472 473 S->AddDecl(D); 474 IdResolver.AddDecl(D); 475} 476 477bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 478 return IdResolver.isDeclInScope(D, Ctx, Context, S); 479} 480 481static bool isOutOfScopePreviousDeclaration(NamedDecl *, 482 DeclContext*, 483 ASTContext&); 484 485/// Filters out lookup results that don't fall within the given scope 486/// as determined by isDeclInScope. 487static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 488 DeclContext *Ctx, Scope *S, 489 bool ConsiderLinkage) { 490 LookupResult::Filter F = R.makeFilter(); 491 while (F.hasNext()) { 492 NamedDecl *D = F.next(); 493 494 if (SemaRef.isDeclInScope(D, Ctx, S)) 495 continue; 496 497 if (ConsiderLinkage && 498 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 499 continue; 500 501 F.erase(); 502 } 503 504 F.done(); 505} 506 507static bool isUsingDecl(NamedDecl *D) { 508 return isa<UsingShadowDecl>(D) || 509 isa<UnresolvedUsingTypenameDecl>(D) || 510 isa<UnresolvedUsingValueDecl>(D); 511} 512 513/// Removes using shadow declarations from the lookup results. 514static void RemoveUsingDecls(LookupResult &R) { 515 LookupResult::Filter F = R.makeFilter(); 516 while (F.hasNext()) 517 if (isUsingDecl(F.next())) 518 F.erase(); 519 520 F.done(); 521} 522 523/// \brief Check for this common pattern: 524/// @code 525/// class S { 526/// S(const S&); // DO NOT IMPLEMENT 527/// void operator=(const S&); // DO NOT IMPLEMENT 528/// }; 529/// @endcode 530static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 531 // FIXME: Should check for private access too but access is set after we get 532 // the decl here. 533 if (D->isThisDeclarationADefinition()) 534 return false; 535 536 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 537 return CD->isCopyConstructor(); 538 return D->isCopyAssignment(); 539} 540 541bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 542 assert(D); 543 544 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 545 return false; 546 547 // Ignore class templates. 548 if (D->getDeclContext()->isDependentContext()) 549 return false; 550 551 // We warn for unused decls internal to the translation unit. 552 if (D->getLinkage() == ExternalLinkage) 553 return false; 554 555 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 556 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 557 return false; 558 559 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 560 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 561 return false; 562 } else { 563 // 'static inline' functions are used in headers; don't warn. 564 if (FD->getStorageClass() == FunctionDecl::Static && 565 FD->isInlineSpecified()) 566 return false; 567 } 568 569 if (FD->isThisDeclarationADefinition()) 570 return !Context.DeclMustBeEmitted(FD); 571 return true; 572 } 573 574 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 575 if (VD->isStaticDataMember() && 576 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 577 return false; 578 579 if ( VD->isFileVarDecl() && 580 !VD->getType().isConstant(Context)) 581 return !Context.DeclMustBeEmitted(VD); 582 } 583 584 return false; 585 } 586 587 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 588 if (!D) 589 return; 590 591 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 592 const FunctionDecl *First = FD->getFirstDeclaration(); 593 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 594 return; // First should already be in the vector. 595 } 596 597 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 598 const VarDecl *First = VD->getFirstDeclaration(); 599 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 600 return; // First should already be in the vector. 601 } 602 603 if (ShouldWarnIfUnusedFileScopedDecl(D)) 604 UnusedFileScopedDecls.push_back(D); 605 } 606 607static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 608 if (D->isInvalidDecl()) 609 return false; 610 611 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 612 return false; 613 614 // White-list anything that isn't a local variable. 615 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 616 !D->getDeclContext()->isFunctionOrMethod()) 617 return false; 618 619 // Types of valid local variables should be complete, so this should succeed. 620 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 621 622 // White-list anything with an __attribute__((unused)) type. 623 QualType Ty = VD->getType(); 624 625 // Only look at the outermost level of typedef. 626 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 627 if (TT->getDecl()->hasAttr<UnusedAttr>()) 628 return false; 629 } 630 631 // If we failed to complete the type for some reason, or if the type is 632 // dependent, don't diagnose the variable. 633 if (Ty->isIncompleteType() || Ty->isDependentType()) 634 return false; 635 636 if (const TagType *TT = Ty->getAs<TagType>()) { 637 const TagDecl *Tag = TT->getDecl(); 638 if (Tag->hasAttr<UnusedAttr>()) 639 return false; 640 641 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 642 // FIXME: Checking for the presence of a user-declared constructor 643 // isn't completely accurate; we'd prefer to check that the initializer 644 // has no side effects. 645 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 646 return false; 647 } 648 } 649 650 // TODO: __attribute__((unused)) templates? 651 } 652 653 return true; 654} 655 656void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 657 if (!ShouldDiagnoseUnusedDecl(D)) 658 return; 659 660 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 661 Diag(D->getLocation(), diag::warn_unused_exception_param) 662 << D->getDeclName(); 663 else 664 Diag(D->getLocation(), diag::warn_unused_variable) 665 << D->getDeclName(); 666} 667 668void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 669 if (S->decl_empty()) return; 670 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 671 "Scope shouldn't contain decls!"); 672 673 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 674 I != E; ++I) { 675 Decl *TmpD = (*I); 676 assert(TmpD && "This decl didn't get pushed??"); 677 678 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 679 NamedDecl *D = cast<NamedDecl>(TmpD); 680 681 if (!D->getDeclName()) continue; 682 683 // Diagnose unused variables in this scope. 684 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 685 DiagnoseUnusedDecl(D); 686 687 // Remove this name from our lexical scope. 688 IdResolver.RemoveDecl(D); 689 } 690} 691 692/// \brief Look for an Objective-C class in the translation unit. 693/// 694/// \param Id The name of the Objective-C class we're looking for. If 695/// typo-correction fixes this name, the Id will be updated 696/// to the fixed name. 697/// 698/// \param IdLoc The location of the name in the translation unit. 699/// 700/// \param TypoCorrection If true, this routine will attempt typo correction 701/// if there is no class with the given name. 702/// 703/// \returns The declaration of the named Objective-C class, or NULL if the 704/// class could not be found. 705ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 706 SourceLocation IdLoc, 707 bool TypoCorrection) { 708 // The third "scope" argument is 0 since we aren't enabling lazy built-in 709 // creation from this context. 710 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 711 712 if (!IDecl && TypoCorrection) { 713 // Perform typo correction at the given location, but only if we 714 // find an Objective-C class name. 715 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 716 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 717 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 718 Diag(IdLoc, diag::err_undef_interface_suggest) 719 << Id << IDecl->getDeclName() 720 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 721 Diag(IDecl->getLocation(), diag::note_previous_decl) 722 << IDecl->getDeclName(); 723 724 Id = IDecl->getIdentifier(); 725 } 726 } 727 728 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 729} 730 731/// getNonFieldDeclScope - Retrieves the innermost scope, starting 732/// from S, where a non-field would be declared. This routine copes 733/// with the difference between C and C++ scoping rules in structs and 734/// unions. For example, the following code is well-formed in C but 735/// ill-formed in C++: 736/// @code 737/// struct S6 { 738/// enum { BAR } e; 739/// }; 740/// 741/// void test_S6() { 742/// struct S6 a; 743/// a.e = BAR; 744/// } 745/// @endcode 746/// For the declaration of BAR, this routine will return a different 747/// scope. The scope S will be the scope of the unnamed enumeration 748/// within S6. In C++, this routine will return the scope associated 749/// with S6, because the enumeration's scope is a transparent 750/// context but structures can contain non-field names. In C, this 751/// routine will return the translation unit scope, since the 752/// enumeration's scope is a transparent context and structures cannot 753/// contain non-field names. 754Scope *Sema::getNonFieldDeclScope(Scope *S) { 755 while (((S->getFlags() & Scope::DeclScope) == 0) || 756 (S->getEntity() && 757 ((DeclContext *)S->getEntity())->isTransparentContext()) || 758 (S->isClassScope() && !getLangOptions().CPlusPlus)) 759 S = S->getParent(); 760 return S; 761} 762 763void Sema::InitBuiltinVaListType() { 764 if (!Context.getBuiltinVaListType().isNull()) 765 return; 766 767 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 768 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 769 LookupOrdinaryName, ForRedeclaration); 770 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 771 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 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 if (Context.BuiltinInfo.hasVAListUse(BID)) 784 InitBuiltinVaListType(); 785 786 ASTContext::GetBuiltinTypeError Error; 787 QualType R = Context.GetBuiltinType(BID, Error); 788 switch (Error) { 789 case ASTContext::GE_None: 790 // Okay 791 break; 792 793 case ASTContext::GE_Missing_stdio: 794 if (ForRedeclaration) 795 Diag(Loc, diag::err_implicit_decl_requires_stdio) 796 << Context.BuiltinInfo.GetName(BID); 797 return 0; 798 799 case ASTContext::GE_Missing_setjmp: 800 if (ForRedeclaration) 801 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 802 << Context.BuiltinInfo.GetName(BID); 803 return 0; 804 } 805 806 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 807 Diag(Loc, diag::ext_implicit_lib_function_decl) 808 << Context.BuiltinInfo.GetName(BID) 809 << R; 810 if (Context.BuiltinInfo.getHeaderName(BID) && 811 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 812 != Diagnostic::Ignored) 813 Diag(Loc, diag::note_please_include_header) 814 << Context.BuiltinInfo.getHeaderName(BID) 815 << Context.BuiltinInfo.GetName(BID); 816 } 817 818 FunctionDecl *New = FunctionDecl::Create(Context, 819 Context.getTranslationUnitDecl(), 820 Loc, II, R, /*TInfo=*/0, 821 FunctionDecl::Extern, 822 FunctionDecl::None, false, 823 /*hasPrototype=*/true); 824 New->setImplicit(); 825 826 // Create Decl objects for each parameter, adding them to the 827 // FunctionDecl. 828 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 829 llvm::SmallVector<ParmVarDecl*, 16> Params; 830 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 831 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 832 FT->getArgType(i), /*TInfo=*/0, 833 VarDecl::None, VarDecl::None, 0)); 834 New->setParams(Params.data(), Params.size()); 835 } 836 837 AddKnownFunctionAttributes(New); 838 839 // TUScope is the translation-unit scope to insert this function into. 840 // FIXME: This is hideous. We need to teach PushOnScopeChains to 841 // relate Scopes to DeclContexts, and probably eliminate CurContext 842 // entirely, but we're not there yet. 843 DeclContext *SavedContext = CurContext; 844 CurContext = Context.getTranslationUnitDecl(); 845 PushOnScopeChains(New, TUScope); 846 CurContext = SavedContext; 847 return New; 848} 849 850/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 851/// same name and scope as a previous declaration 'Old'. Figure out 852/// how to resolve this situation, merging decls or emitting 853/// diagnostics as appropriate. If there was an error, set New to be invalid. 854/// 855void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 856 // If the new decl is known invalid already, don't bother doing any 857 // merging checks. 858 if (New->isInvalidDecl()) return; 859 860 // Allow multiple definitions for ObjC built-in typedefs. 861 // FIXME: Verify the underlying types are equivalent! 862 if (getLangOptions().ObjC1) { 863 const IdentifierInfo *TypeID = New->getIdentifier(); 864 switch (TypeID->getLength()) { 865 default: break; 866 case 2: 867 if (!TypeID->isStr("id")) 868 break; 869 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 870 // Install the built-in type for 'id', ignoring the current definition. 871 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 872 return; 873 case 5: 874 if (!TypeID->isStr("Class")) 875 break; 876 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 877 // Install the built-in type for 'Class', ignoring the current definition. 878 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 879 return; 880 case 3: 881 if (!TypeID->isStr("SEL")) 882 break; 883 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 884 // Install the built-in type for 'SEL', ignoring the current definition. 885 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 886 return; 887 case 8: 888 if (!TypeID->isStr("Protocol")) 889 break; 890 Context.setObjCProtoType(New->getUnderlyingType()); 891 return; 892 } 893 // Fall through - the typedef name was not a builtin type. 894 } 895 896 // Verify the old decl was also a type. 897 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 898 if (!Old) { 899 Diag(New->getLocation(), diag::err_redefinition_different_kind) 900 << New->getDeclName(); 901 902 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 903 if (OldD->getLocation().isValid()) 904 Diag(OldD->getLocation(), diag::note_previous_definition); 905 906 return New->setInvalidDecl(); 907 } 908 909 // If the old declaration is invalid, just give up here. 910 if (Old->isInvalidDecl()) 911 return New->setInvalidDecl(); 912 913 // Determine the "old" type we'll use for checking and diagnostics. 914 QualType OldType; 915 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 916 OldType = OldTypedef->getUnderlyingType(); 917 else 918 OldType = Context.getTypeDeclType(Old); 919 920 // If the typedef types are not identical, reject them in all languages and 921 // with any extensions enabled. 922 923 if (OldType != New->getUnderlyingType() && 924 Context.getCanonicalType(OldType) != 925 Context.getCanonicalType(New->getUnderlyingType())) { 926 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 927 << New->getUnderlyingType() << OldType; 928 if (Old->getLocation().isValid()) 929 Diag(Old->getLocation(), diag::note_previous_definition); 930 return New->setInvalidDecl(); 931 } 932 933 // The types match. Link up the redeclaration chain if the old 934 // declaration was a typedef. 935 // FIXME: this is a potential source of wierdness if the type 936 // spellings don't match exactly. 937 if (isa<TypedefDecl>(Old)) 938 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 939 940 if (getLangOptions().Microsoft) 941 return; 942 943 if (getLangOptions().CPlusPlus) { 944 // C++ [dcl.typedef]p2: 945 // In a given non-class scope, a typedef specifier can be used to 946 // redefine the name of any type declared in that scope to refer 947 // to the type to which it already refers. 948 if (!isa<CXXRecordDecl>(CurContext)) 949 return; 950 951 // C++0x [dcl.typedef]p4: 952 // In a given class scope, a typedef specifier can be used to redefine 953 // any class-name declared in that scope that is not also a typedef-name 954 // to refer to the type to which it already refers. 955 // 956 // This wording came in via DR424, which was a correction to the 957 // wording in DR56, which accidentally banned code like: 958 // 959 // struct S { 960 // typedef struct A { } A; 961 // }; 962 // 963 // in the C++03 standard. We implement the C++0x semantics, which 964 // allow the above but disallow 965 // 966 // struct S { 967 // typedef int I; 968 // typedef int I; 969 // }; 970 // 971 // since that was the intent of DR56. 972 if (!isa<TypedefDecl >(Old)) 973 return; 974 975 Diag(New->getLocation(), diag::err_redefinition) 976 << New->getDeclName(); 977 Diag(Old->getLocation(), diag::note_previous_definition); 978 return New->setInvalidDecl(); 979 } 980 981 // If we have a redefinition of a typedef in C, emit a warning. This warning 982 // is normally mapped to an error, but can be controlled with 983 // -Wtypedef-redefinition. If either the original or the redefinition is 984 // in a system header, don't emit this for compatibility with GCC. 985 if (getDiagnostics().getSuppressSystemWarnings() && 986 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 987 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 988 return; 989 990 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 991 << New->getDeclName(); 992 Diag(Old->getLocation(), diag::note_previous_definition); 993 return; 994} 995 996/// DeclhasAttr - returns true if decl Declaration already has the target 997/// attribute. 998static bool 999DeclHasAttr(const Decl *D, const Attr *A) { 1000 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1001 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1002 if ((*i)->getKind() == A->getKind()) { 1003 // FIXME: Don't hardcode this check 1004 if (OA && isa<OwnershipAttr>(*i)) 1005 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1006 return true; 1007 } 1008 1009 return false; 1010} 1011 1012/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1013static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1014 if (!Old->hasAttrs()) 1015 return; 1016 // Ensure that any moving of objects within the allocated map is done before 1017 // we process them. 1018 if (!New->hasAttrs()) 1019 New->setAttrs(AttrVec()); 1020 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1021 ++i) { 1022 // FIXME: Make this more general than just checking for Overloadable. 1023 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1024 Attr *NewAttr = (*i)->clone(C); 1025 NewAttr->setInherited(true); 1026 New->addAttr(NewAttr); 1027 } 1028 } 1029} 1030 1031namespace { 1032 1033/// Used in MergeFunctionDecl to keep track of function parameters in 1034/// C. 1035struct GNUCompatibleParamWarning { 1036 ParmVarDecl *OldParm; 1037 ParmVarDecl *NewParm; 1038 QualType PromotedType; 1039}; 1040 1041} 1042 1043/// getSpecialMember - get the special member enum for a method. 1044Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1045 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1046 if (Ctor->isCopyConstructor()) 1047 return Sema::CXXCopyConstructor; 1048 1049 return Sema::CXXConstructor; 1050 } 1051 1052 if (isa<CXXDestructorDecl>(MD)) 1053 return Sema::CXXDestructor; 1054 1055 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 1056 return Sema::CXXCopyAssignment; 1057} 1058 1059/// canRedefineFunction - checks if a function can be redefined. Currently, 1060/// only extern inline functions can be redefined, and even then only in 1061/// GNU89 mode. 1062static bool canRedefineFunction(const FunctionDecl *FD, 1063 const LangOptions& LangOpts) { 1064 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1065 FD->isInlineSpecified() && 1066 FD->getStorageClass() == FunctionDecl::Extern); 1067} 1068 1069/// MergeFunctionDecl - We just parsed a function 'New' from 1070/// declarator D which has the same name and scope as a previous 1071/// declaration 'Old'. Figure out how to resolve this situation, 1072/// merging decls or emitting diagnostics as appropriate. 1073/// 1074/// In C++, New and Old must be declarations that are not 1075/// overloaded. Use IsOverload to determine whether New and Old are 1076/// overloaded, and to select the Old declaration that New should be 1077/// merged with. 1078/// 1079/// Returns true if there was an error, false otherwise. 1080bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1081 // Verify the old decl was also a function. 1082 FunctionDecl *Old = 0; 1083 if (FunctionTemplateDecl *OldFunctionTemplate 1084 = dyn_cast<FunctionTemplateDecl>(OldD)) 1085 Old = OldFunctionTemplate->getTemplatedDecl(); 1086 else 1087 Old = dyn_cast<FunctionDecl>(OldD); 1088 if (!Old) { 1089 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1090 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1091 Diag(Shadow->getTargetDecl()->getLocation(), 1092 diag::note_using_decl_target); 1093 Diag(Shadow->getUsingDecl()->getLocation(), 1094 diag::note_using_decl) << 0; 1095 return true; 1096 } 1097 1098 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1099 << New->getDeclName(); 1100 Diag(OldD->getLocation(), diag::note_previous_definition); 1101 return true; 1102 } 1103 1104 // Determine whether the previous declaration was a definition, 1105 // implicit declaration, or a declaration. 1106 diag::kind PrevDiag; 1107 if (Old->isThisDeclarationADefinition()) 1108 PrevDiag = diag::note_previous_definition; 1109 else if (Old->isImplicit()) 1110 PrevDiag = diag::note_previous_implicit_declaration; 1111 else 1112 PrevDiag = diag::note_previous_declaration; 1113 1114 QualType OldQType = Context.getCanonicalType(Old->getType()); 1115 QualType NewQType = Context.getCanonicalType(New->getType()); 1116 1117 // Don't complain about this if we're in GNU89 mode and the old function 1118 // is an extern inline function. 1119 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1120 New->getStorageClass() == FunctionDecl::Static && 1121 Old->getStorageClass() != FunctionDecl::Static && 1122 !canRedefineFunction(Old, getLangOptions())) { 1123 Diag(New->getLocation(), diag::err_static_non_static) 1124 << New; 1125 Diag(Old->getLocation(), PrevDiag); 1126 return true; 1127 } 1128 1129 // If a function is first declared with a calling convention, but is 1130 // later declared or defined without one, the second decl assumes the 1131 // calling convention of the first. 1132 // 1133 // For the new decl, we have to look at the NON-canonical type to tell the 1134 // difference between a function that really doesn't have a calling 1135 // convention and one that is declared cdecl. That's because in 1136 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1137 // because it is the default calling convention. 1138 // 1139 // Note also that we DO NOT return at this point, because we still have 1140 // other tests to run. 1141 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1142 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1143 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1144 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1145 if (OldTypeInfo.getCC() != CC_Default && 1146 NewTypeInfo.getCC() == CC_Default) { 1147 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1148 New->setType(NewQType); 1149 NewQType = Context.getCanonicalType(NewQType); 1150 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1151 NewTypeInfo.getCC())) { 1152 // Calling conventions really aren't compatible, so complain. 1153 Diag(New->getLocation(), diag::err_cconv_change) 1154 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1155 << (OldTypeInfo.getCC() == CC_Default) 1156 << (OldTypeInfo.getCC() == CC_Default ? "" : 1157 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1158 Diag(Old->getLocation(), diag::note_previous_declaration); 1159 return true; 1160 } 1161 1162 // FIXME: diagnose the other way around? 1163 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1164 NewQType = Context.getNoReturnType(NewQType); 1165 New->setType(NewQType); 1166 assert(NewQType.isCanonical()); 1167 } 1168 1169 // Merge regparm attribute. 1170 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1171 if (NewType->getRegParmType()) { 1172 Diag(New->getLocation(), diag::err_regparm_mismatch) 1173 << NewType->getRegParmType() 1174 << OldType->getRegParmType(); 1175 Diag(Old->getLocation(), diag::note_previous_declaration); 1176 return true; 1177 } 1178 1179 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1180 New->setType(NewQType); 1181 assert(NewQType.isCanonical()); 1182 } 1183 1184 if (getLangOptions().CPlusPlus) { 1185 // (C++98 13.1p2): 1186 // Certain function declarations cannot be overloaded: 1187 // -- Function declarations that differ only in the return type 1188 // cannot be overloaded. 1189 QualType OldReturnType 1190 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1191 QualType NewReturnType 1192 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1193 QualType ResQT; 1194 if (OldReturnType != NewReturnType) { 1195 if (NewReturnType->isObjCObjectPointerType() 1196 && OldReturnType->isObjCObjectPointerType()) 1197 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1198 if (ResQT.isNull()) { 1199 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1200 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1201 return true; 1202 } 1203 else 1204 NewQType = ResQT; 1205 } 1206 1207 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1208 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1209 if (OldMethod && NewMethod) { 1210 // Preserve triviality. 1211 NewMethod->setTrivial(OldMethod->isTrivial()); 1212 1213 bool isFriend = NewMethod->getFriendObjectKind(); 1214 1215 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1216 // -- Member function declarations with the same name and the 1217 // same parameter types cannot be overloaded if any of them 1218 // is a static member function declaration. 1219 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1220 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1221 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1222 return true; 1223 } 1224 1225 // C++ [class.mem]p1: 1226 // [...] A member shall not be declared twice in the 1227 // member-specification, except that a nested class or member 1228 // class template can be declared and then later defined. 1229 unsigned NewDiag; 1230 if (isa<CXXConstructorDecl>(OldMethod)) 1231 NewDiag = diag::err_constructor_redeclared; 1232 else if (isa<CXXDestructorDecl>(NewMethod)) 1233 NewDiag = diag::err_destructor_redeclared; 1234 else if (isa<CXXConversionDecl>(NewMethod)) 1235 NewDiag = diag::err_conv_function_redeclared; 1236 else 1237 NewDiag = diag::err_member_redeclared; 1238 1239 Diag(New->getLocation(), NewDiag); 1240 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1241 1242 // Complain if this is an explicit declaration of a special 1243 // member that was initially declared implicitly. 1244 // 1245 // As an exception, it's okay to befriend such methods in order 1246 // to permit the implicit constructor/destructor/operator calls. 1247 } else if (OldMethod->isImplicit()) { 1248 if (isFriend) { 1249 NewMethod->setImplicit(); 1250 } else { 1251 Diag(NewMethod->getLocation(), 1252 diag::err_definition_of_implicitly_declared_member) 1253 << New << getSpecialMember(OldMethod); 1254 return true; 1255 } 1256 } 1257 } 1258 1259 // (C++98 8.3.5p3): 1260 // All declarations for a function shall agree exactly in both the 1261 // return type and the parameter-type-list. 1262 // attributes should be ignored when comparing. 1263 if (Context.getNoReturnType(OldQType, false) == 1264 Context.getNoReturnType(NewQType, false)) 1265 return MergeCompatibleFunctionDecls(New, Old); 1266 1267 // Fall through for conflicting redeclarations and redefinitions. 1268 } 1269 1270 // C: Function types need to be compatible, not identical. This handles 1271 // duplicate function decls like "void f(int); void f(enum X);" properly. 1272 if (!getLangOptions().CPlusPlus && 1273 Context.typesAreCompatible(OldQType, NewQType)) { 1274 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1275 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1276 const FunctionProtoType *OldProto = 0; 1277 if (isa<FunctionNoProtoType>(NewFuncType) && 1278 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1279 // The old declaration provided a function prototype, but the 1280 // new declaration does not. Merge in the prototype. 1281 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1282 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1283 OldProto->arg_type_end()); 1284 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1285 ParamTypes.data(), ParamTypes.size(), 1286 OldProto->isVariadic(), 1287 OldProto->getTypeQuals(), 1288 false, false, 0, 0, 1289 OldProto->getExtInfo()); 1290 New->setType(NewQType); 1291 New->setHasInheritedPrototype(); 1292 1293 // Synthesize a parameter for each argument type. 1294 llvm::SmallVector<ParmVarDecl*, 16> Params; 1295 for (FunctionProtoType::arg_type_iterator 1296 ParamType = OldProto->arg_type_begin(), 1297 ParamEnd = OldProto->arg_type_end(); 1298 ParamType != ParamEnd; ++ParamType) { 1299 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1300 SourceLocation(), 0, 1301 *ParamType, /*TInfo=*/0, 1302 VarDecl::None, VarDecl::None, 1303 0); 1304 Param->setImplicit(); 1305 Params.push_back(Param); 1306 } 1307 1308 New->setParams(Params.data(), Params.size()); 1309 } 1310 1311 return MergeCompatibleFunctionDecls(New, Old); 1312 } 1313 1314 // GNU C permits a K&R definition to follow a prototype declaration 1315 // if the declared types of the parameters in the K&R definition 1316 // match the types in the prototype declaration, even when the 1317 // promoted types of the parameters from the K&R definition differ 1318 // from the types in the prototype. GCC then keeps the types from 1319 // the prototype. 1320 // 1321 // If a variadic prototype is followed by a non-variadic K&R definition, 1322 // the K&R definition becomes variadic. This is sort of an edge case, but 1323 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1324 // C99 6.9.1p8. 1325 if (!getLangOptions().CPlusPlus && 1326 Old->hasPrototype() && !New->hasPrototype() && 1327 New->getType()->getAs<FunctionProtoType>() && 1328 Old->getNumParams() == New->getNumParams()) { 1329 llvm::SmallVector<QualType, 16> ArgTypes; 1330 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1331 const FunctionProtoType *OldProto 1332 = Old->getType()->getAs<FunctionProtoType>(); 1333 const FunctionProtoType *NewProto 1334 = New->getType()->getAs<FunctionProtoType>(); 1335 1336 // Determine whether this is the GNU C extension. 1337 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1338 NewProto->getResultType()); 1339 bool LooseCompatible = !MergedReturn.isNull(); 1340 for (unsigned Idx = 0, End = Old->getNumParams(); 1341 LooseCompatible && Idx != End; ++Idx) { 1342 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1343 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1344 if (Context.typesAreCompatible(OldParm->getType(), 1345 NewProto->getArgType(Idx))) { 1346 ArgTypes.push_back(NewParm->getType()); 1347 } else if (Context.typesAreCompatible(OldParm->getType(), 1348 NewParm->getType(), 1349 /*CompareUnqualified=*/true)) { 1350 GNUCompatibleParamWarning Warn 1351 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1352 Warnings.push_back(Warn); 1353 ArgTypes.push_back(NewParm->getType()); 1354 } else 1355 LooseCompatible = false; 1356 } 1357 1358 if (LooseCompatible) { 1359 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1360 Diag(Warnings[Warn].NewParm->getLocation(), 1361 diag::ext_param_promoted_not_compatible_with_prototype) 1362 << Warnings[Warn].PromotedType 1363 << Warnings[Warn].OldParm->getType(); 1364 if (Warnings[Warn].OldParm->getLocation().isValid()) 1365 Diag(Warnings[Warn].OldParm->getLocation(), 1366 diag::note_previous_declaration); 1367 } 1368 1369 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1370 ArgTypes.size(), 1371 OldProto->isVariadic(), 0, 1372 false, false, 0, 0, 1373 OldProto->getExtInfo())); 1374 return MergeCompatibleFunctionDecls(New, Old); 1375 } 1376 1377 // Fall through to diagnose conflicting types. 1378 } 1379 1380 // A function that has already been declared has been redeclared or defined 1381 // with a different type- show appropriate diagnostic 1382 if (unsigned BuiltinID = Old->getBuiltinID()) { 1383 // The user has declared a builtin function with an incompatible 1384 // signature. 1385 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1386 // The function the user is redeclaring is a library-defined 1387 // function like 'malloc' or 'printf'. Warn about the 1388 // redeclaration, then pretend that we don't know about this 1389 // library built-in. 1390 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1391 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1392 << Old << Old->getType(); 1393 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1394 Old->setInvalidDecl(); 1395 return false; 1396 } 1397 1398 PrevDiag = diag::note_previous_builtin_declaration; 1399 } 1400 1401 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1402 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1403 return true; 1404} 1405 1406/// \brief Completes the merge of two function declarations that are 1407/// known to be compatible. 1408/// 1409/// This routine handles the merging of attributes and other 1410/// properties of function declarations form the old declaration to 1411/// the new declaration, once we know that New is in fact a 1412/// redeclaration of Old. 1413/// 1414/// \returns false 1415bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1416 // Merge the attributes 1417 MergeDeclAttributes(New, Old, Context); 1418 1419 // Merge the storage class. 1420 if (Old->getStorageClass() != FunctionDecl::Extern && 1421 Old->getStorageClass() != FunctionDecl::None) 1422 New->setStorageClass(Old->getStorageClass()); 1423 1424 // Merge "pure" flag. 1425 if (Old->isPure()) 1426 New->setPure(); 1427 1428 // Merge the "deleted" flag. 1429 if (Old->isDeleted()) 1430 New->setDeleted(); 1431 1432 if (getLangOptions().CPlusPlus) 1433 return MergeCXXFunctionDecl(New, Old); 1434 1435 return false; 1436} 1437 1438/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1439/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1440/// situation, merging decls or emitting diagnostics as appropriate. 1441/// 1442/// Tentative definition rules (C99 6.9.2p2) are checked by 1443/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1444/// definitions here, since the initializer hasn't been attached. 1445/// 1446void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1447 // If the new decl is already invalid, don't do any other checking. 1448 if (New->isInvalidDecl()) 1449 return; 1450 1451 // Verify the old decl was also a variable. 1452 VarDecl *Old = 0; 1453 if (!Previous.isSingleResult() || 1454 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1455 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1456 << New->getDeclName(); 1457 Diag(Previous.getRepresentativeDecl()->getLocation(), 1458 diag::note_previous_definition); 1459 return New->setInvalidDecl(); 1460 } 1461 1462 MergeDeclAttributes(New, Old, Context); 1463 1464 // Merge the types 1465 QualType MergedT; 1466 if (getLangOptions().CPlusPlus) { 1467 if (Context.hasSameType(New->getType(), Old->getType())) 1468 MergedT = New->getType(); 1469 // C++ [basic.link]p10: 1470 // [...] the types specified by all declarations referring to a given 1471 // object or function shall be identical, except that declarations for an 1472 // array object can specify array types that differ by the presence or 1473 // absence of a major array bound (8.3.4). 1474 else if (Old->getType()->isIncompleteArrayType() && 1475 New->getType()->isArrayType()) { 1476 CanQual<ArrayType> OldArray 1477 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1478 CanQual<ArrayType> NewArray 1479 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1480 if (OldArray->getElementType() == NewArray->getElementType()) 1481 MergedT = New->getType(); 1482 } else if (Old->getType()->isArrayType() && 1483 New->getType()->isIncompleteArrayType()) { 1484 CanQual<ArrayType> OldArray 1485 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1486 CanQual<ArrayType> NewArray 1487 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1488 if (OldArray->getElementType() == NewArray->getElementType()) 1489 MergedT = Old->getType(); 1490 } else if (New->getType()->isObjCObjectPointerType() 1491 && Old->getType()->isObjCObjectPointerType()) { 1492 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1493 } 1494 } else { 1495 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1496 } 1497 if (MergedT.isNull()) { 1498 Diag(New->getLocation(), diag::err_redefinition_different_type) 1499 << New->getDeclName(); 1500 Diag(Old->getLocation(), diag::note_previous_definition); 1501 return New->setInvalidDecl(); 1502 } 1503 New->setType(MergedT); 1504 1505 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1506 if (New->getStorageClass() == VarDecl::Static && 1507 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1508 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1509 Diag(Old->getLocation(), diag::note_previous_definition); 1510 return New->setInvalidDecl(); 1511 } 1512 // C99 6.2.2p4: 1513 // For an identifier declared with the storage-class specifier 1514 // extern in a scope in which a prior declaration of that 1515 // identifier is visible,23) if the prior declaration specifies 1516 // internal or external linkage, the linkage of the identifier at 1517 // the later declaration is the same as the linkage specified at 1518 // the prior declaration. If no prior declaration is visible, or 1519 // if the prior declaration specifies no linkage, then the 1520 // identifier has external linkage. 1521 if (New->hasExternalStorage() && Old->hasLinkage()) 1522 /* Okay */; 1523 else if (New->getStorageClass() != VarDecl::Static && 1524 Old->getStorageClass() == VarDecl::Static) { 1525 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1526 Diag(Old->getLocation(), diag::note_previous_definition); 1527 return New->setInvalidDecl(); 1528 } 1529 1530 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1531 1532 // FIXME: The test for external storage here seems wrong? We still 1533 // need to check for mismatches. 1534 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1535 // Don't complain about out-of-line definitions of static members. 1536 !(Old->getLexicalDeclContext()->isRecord() && 1537 !New->getLexicalDeclContext()->isRecord())) { 1538 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1539 Diag(Old->getLocation(), diag::note_previous_definition); 1540 return New->setInvalidDecl(); 1541 } 1542 1543 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1544 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1545 Diag(Old->getLocation(), diag::note_previous_definition); 1546 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1547 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1548 Diag(Old->getLocation(), diag::note_previous_definition); 1549 } 1550 1551 // C++ doesn't have tentative definitions, so go right ahead and check here. 1552 const VarDecl *Def; 1553 if (getLangOptions().CPlusPlus && 1554 New->isThisDeclarationADefinition() == VarDecl::Definition && 1555 (Def = Old->getDefinition())) { 1556 Diag(New->getLocation(), diag::err_redefinition) 1557 << New->getDeclName(); 1558 Diag(Def->getLocation(), diag::note_previous_definition); 1559 New->setInvalidDecl(); 1560 return; 1561 } 1562 // c99 6.2.2 P4. 1563 // For an identifier declared with the storage-class specifier extern in a 1564 // scope in which a prior declaration of that identifier is visible, if 1565 // the prior declaration specifies internal or external linkage, the linkage 1566 // of the identifier at the later declaration is the same as the linkage 1567 // specified at the prior declaration. 1568 // FIXME. revisit this code. 1569 if (New->hasExternalStorage() && 1570 Old->getLinkage() == InternalLinkage && 1571 New->getDeclContext() == Old->getDeclContext()) 1572 New->setStorageClass(Old->getStorageClass()); 1573 1574 // Keep a chain of previous declarations. 1575 New->setPreviousDeclaration(Old); 1576 1577 // Inherit access appropriately. 1578 New->setAccess(Old->getAccess()); 1579} 1580 1581/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1582/// no declarator (e.g. "struct foo;") is parsed. 1583Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1584 DeclSpec &DS) { 1585 // FIXME: Error on auto/register at file scope 1586 // FIXME: Error on inline/virtual/explicit 1587 // FIXME: Warn on useless __thread 1588 // FIXME: Warn on useless const/volatile 1589 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1590 // FIXME: Warn on useless attributes 1591 Decl *TagD = 0; 1592 TagDecl *Tag = 0; 1593 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1594 DS.getTypeSpecType() == DeclSpec::TST_struct || 1595 DS.getTypeSpecType() == DeclSpec::TST_union || 1596 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1597 TagD = static_cast<Decl *>(DS.getTypeRep()); 1598 1599 if (!TagD) // We probably had an error 1600 return 0; 1601 1602 // Note that the above type specs guarantee that the 1603 // type rep is a Decl, whereas in many of the others 1604 // it's a Type. 1605 Tag = dyn_cast<TagDecl>(TagD); 1606 } 1607 1608 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1609 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1610 // or incomplete types shall not be restrict-qualified." 1611 if (TypeQuals & DeclSpec::TQ_restrict) 1612 Diag(DS.getRestrictSpecLoc(), 1613 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1614 << DS.getSourceRange(); 1615 } 1616 1617 if (DS.isFriendSpecified()) { 1618 // If we're dealing with a class template decl, assume that the 1619 // template routines are handling it. 1620 if (TagD && isa<ClassTemplateDecl>(TagD)) 1621 return 0; 1622 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1623 } 1624 1625 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1626 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1627 1628 if (!Record->getDeclName() && Record->isDefinition() && 1629 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1630 if (getLangOptions().CPlusPlus || 1631 Record->getDeclContext()->isRecord()) 1632 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1633 1634 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1635 << DS.getSourceRange(); 1636 } 1637 1638 // Microsoft allows unnamed struct/union fields. Don't complain 1639 // about them. 1640 // FIXME: Should we support Microsoft's extensions in this area? 1641 if (Record->getDeclName() && getLangOptions().Microsoft) 1642 return Tag; 1643 } 1644 1645 if (getLangOptions().CPlusPlus && 1646 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1647 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1648 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1649 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1650 Diag(Enum->getLocation(), diag::ext_no_declarators) 1651 << DS.getSourceRange(); 1652 1653 if (!DS.isMissingDeclaratorOk() && 1654 DS.getTypeSpecType() != DeclSpec::TST_error) { 1655 // Warn about typedefs of enums without names, since this is an 1656 // extension in both Microsoft and GNU. 1657 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1658 Tag && isa<EnumDecl>(Tag)) { 1659 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1660 << DS.getSourceRange(); 1661 return Tag; 1662 } 1663 1664 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1665 << DS.getSourceRange(); 1666 } 1667 1668 return TagD; 1669} 1670 1671/// We are trying to inject an anonymous member into the given scope; 1672/// check if there's an existing declaration that can't be overloaded. 1673/// 1674/// \return true if this is a forbidden redeclaration 1675static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1676 Scope *S, 1677 DeclContext *Owner, 1678 DeclarationName Name, 1679 SourceLocation NameLoc, 1680 unsigned diagnostic) { 1681 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1682 Sema::ForRedeclaration); 1683 if (!SemaRef.LookupName(R, S)) return false; 1684 1685 if (R.getAsSingle<TagDecl>()) 1686 return false; 1687 1688 // Pick a representative declaration. 1689 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1690 if (PrevDecl && Owner->isRecord()) { 1691 RecordDecl *Record = cast<RecordDecl>(Owner); 1692 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1693 return false; 1694 } 1695 1696 SemaRef.Diag(NameLoc, diagnostic) << Name; 1697 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1698 1699 return true; 1700} 1701 1702/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1703/// anonymous struct or union AnonRecord into the owning context Owner 1704/// and scope S. This routine will be invoked just after we realize 1705/// that an unnamed union or struct is actually an anonymous union or 1706/// struct, e.g., 1707/// 1708/// @code 1709/// union { 1710/// int i; 1711/// float f; 1712/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1713/// // f into the surrounding scope.x 1714/// @endcode 1715/// 1716/// This routine is recursive, injecting the names of nested anonymous 1717/// structs/unions into the owning context and scope as well. 1718static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1719 DeclContext *Owner, 1720 RecordDecl *AnonRecord, 1721 AccessSpecifier AS) { 1722 unsigned diagKind 1723 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1724 : diag::err_anonymous_struct_member_redecl; 1725 1726 bool Invalid = false; 1727 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1728 FEnd = AnonRecord->field_end(); 1729 F != FEnd; ++F) { 1730 if ((*F)->getDeclName()) { 1731 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1732 (*F)->getLocation(), diagKind)) { 1733 // C++ [class.union]p2: 1734 // The names of the members of an anonymous union shall be 1735 // distinct from the names of any other entity in the 1736 // scope in which the anonymous union is declared. 1737 Invalid = true; 1738 } else { 1739 // C++ [class.union]p2: 1740 // For the purpose of name lookup, after the anonymous union 1741 // definition, the members of the anonymous union are 1742 // considered to have been defined in the scope in which the 1743 // anonymous union is declared. 1744 Owner->makeDeclVisibleInContext(*F); 1745 S->AddDecl(*F); 1746 SemaRef.IdResolver.AddDecl(*F); 1747 1748 // That includes picking up the appropriate access specifier. 1749 if (AS != AS_none) (*F)->setAccess(AS); 1750 } 1751 } else if (const RecordType *InnerRecordType 1752 = (*F)->getType()->getAs<RecordType>()) { 1753 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1754 if (InnerRecord->isAnonymousStructOrUnion()) 1755 Invalid = Invalid || 1756 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1757 InnerRecord, AS); 1758 } 1759 } 1760 1761 return Invalid; 1762} 1763 1764/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1765/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1766/// illegal input values are mapped to VarDecl::None. 1767static VarDecl::StorageClass 1768StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1769 switch (StorageClassSpec) { 1770 case DeclSpec::SCS_unspecified: return VarDecl::None; 1771 case DeclSpec::SCS_extern: return VarDecl::Extern; 1772 case DeclSpec::SCS_static: return VarDecl::Static; 1773 case DeclSpec::SCS_auto: return VarDecl::Auto; 1774 case DeclSpec::SCS_register: return VarDecl::Register; 1775 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1776 // Illegal SCSs map to None: error reporting is up to the caller. 1777 case DeclSpec::SCS_mutable: // Fall through. 1778 case DeclSpec::SCS_typedef: return VarDecl::None; 1779 } 1780 llvm_unreachable("unknown storage class specifier"); 1781} 1782 1783/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1784/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1785/// illegal input values are mapped to FunctionDecl::None. 1786static FunctionDecl::StorageClass 1787StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1788 switch (StorageClassSpec) { 1789 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1790 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1791 case DeclSpec::SCS_static: return FunctionDecl::Static; 1792 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1793 // Illegal SCSs map to None: error reporting is up to the caller. 1794 case DeclSpec::SCS_auto: // Fall through. 1795 case DeclSpec::SCS_mutable: // Fall through. 1796 case DeclSpec::SCS_register: // Fall through. 1797 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1798 } 1799 llvm_unreachable("unknown storage class specifier"); 1800} 1801 1802/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1803/// anonymous structure or union. Anonymous unions are a C++ feature 1804/// (C++ [class.union]) and a GNU C extension; anonymous structures 1805/// are a GNU C and GNU C++ extension. 1806Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1807 AccessSpecifier AS, 1808 RecordDecl *Record) { 1809 DeclContext *Owner = Record->getDeclContext(); 1810 1811 // Diagnose whether this anonymous struct/union is an extension. 1812 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1813 Diag(Record->getLocation(), diag::ext_anonymous_union); 1814 else if (!Record->isUnion()) 1815 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1816 1817 // C and C++ require different kinds of checks for anonymous 1818 // structs/unions. 1819 bool Invalid = false; 1820 if (getLangOptions().CPlusPlus) { 1821 const char* PrevSpec = 0; 1822 unsigned DiagID; 1823 // C++ [class.union]p3: 1824 // Anonymous unions declared in a named namespace or in the 1825 // global namespace shall be declared static. 1826 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1827 (isa<TranslationUnitDecl>(Owner) || 1828 (isa<NamespaceDecl>(Owner) && 1829 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1830 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1831 Invalid = true; 1832 1833 // Recover by adding 'static'. 1834 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1835 PrevSpec, DiagID); 1836 } 1837 // C++ [class.union]p3: 1838 // A storage class is not allowed in a declaration of an 1839 // anonymous union in a class scope. 1840 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1841 isa<RecordDecl>(Owner)) { 1842 Diag(DS.getStorageClassSpecLoc(), 1843 diag::err_anonymous_union_with_storage_spec); 1844 Invalid = true; 1845 1846 // Recover by removing the storage specifier. 1847 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1848 PrevSpec, DiagID); 1849 } 1850 1851 // C++ [class.union]p2: 1852 // The member-specification of an anonymous union shall only 1853 // define non-static data members. [Note: nested types and 1854 // functions cannot be declared within an anonymous union. ] 1855 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1856 MemEnd = Record->decls_end(); 1857 Mem != MemEnd; ++Mem) { 1858 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1859 // C++ [class.union]p3: 1860 // An anonymous union shall not have private or protected 1861 // members (clause 11). 1862 assert(FD->getAccess() != AS_none); 1863 if (FD->getAccess() != AS_public) { 1864 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1865 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1866 Invalid = true; 1867 } 1868 1869 if (CheckNontrivialField(FD)) 1870 Invalid = true; 1871 } else if ((*Mem)->isImplicit()) { 1872 // Any implicit members are fine. 1873 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1874 // This is a type that showed up in an 1875 // elaborated-type-specifier inside the anonymous struct or 1876 // union, but which actually declares a type outside of the 1877 // anonymous struct or union. It's okay. 1878 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1879 if (!MemRecord->isAnonymousStructOrUnion() && 1880 MemRecord->getDeclName()) { 1881 // This is a nested type declaration. 1882 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1883 << (int)Record->isUnion(); 1884 Invalid = true; 1885 } 1886 } else if (isa<AccessSpecDecl>(*Mem)) { 1887 // Any access specifier is fine. 1888 } else { 1889 // We have something that isn't a non-static data 1890 // member. Complain about it. 1891 unsigned DK = diag::err_anonymous_record_bad_member; 1892 if (isa<TypeDecl>(*Mem)) 1893 DK = diag::err_anonymous_record_with_type; 1894 else if (isa<FunctionDecl>(*Mem)) 1895 DK = diag::err_anonymous_record_with_function; 1896 else if (isa<VarDecl>(*Mem)) 1897 DK = diag::err_anonymous_record_with_static; 1898 Diag((*Mem)->getLocation(), DK) 1899 << (int)Record->isUnion(); 1900 Invalid = true; 1901 } 1902 } 1903 } 1904 1905 if (!Record->isUnion() && !Owner->isRecord()) { 1906 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1907 << (int)getLangOptions().CPlusPlus; 1908 Invalid = true; 1909 } 1910 1911 // Mock up a declarator. 1912 Declarator Dc(DS, Declarator::TypeNameContext); 1913 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1914 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1915 1916 // Create a declaration for this anonymous struct/union. 1917 NamedDecl *Anon = 0; 1918 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1919 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1920 /*IdentifierInfo=*/0, 1921 Context.getTypeDeclType(Record), 1922 TInfo, 1923 /*BitWidth=*/0, /*Mutable=*/false); 1924 Anon->setAccess(AS); 1925 if (getLangOptions().CPlusPlus) { 1926 FieldCollector->Add(cast<FieldDecl>(Anon)); 1927 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1928 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1929 } 1930 } else { 1931 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1932 assert(SCSpec != DeclSpec::SCS_typedef && 1933 "Parser allowed 'typedef' as storage class VarDecl."); 1934 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1935 if (SCSpec == DeclSpec::SCS_mutable) { 1936 // mutable can only appear on non-static class members, so it's always 1937 // an error here 1938 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1939 Invalid = true; 1940 SC = VarDecl::None; 1941 } 1942 SCSpec = DS.getStorageClassSpecAsWritten(); 1943 VarDecl::StorageClass SCAsWritten 1944 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1945 1946 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1947 /*IdentifierInfo=*/0, 1948 Context.getTypeDeclType(Record), 1949 TInfo, SC, SCAsWritten); 1950 } 1951 Anon->setImplicit(); 1952 1953 // Add the anonymous struct/union object to the current 1954 // context. We'll be referencing this object when we refer to one of 1955 // its members. 1956 Owner->addDecl(Anon); 1957 1958 // Inject the members of the anonymous struct/union into the owning 1959 // context and into the identifier resolver chain for name lookup 1960 // purposes. 1961 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1962 Invalid = true; 1963 1964 // Mark this as an anonymous struct/union type. Note that we do not 1965 // do this until after we have already checked and injected the 1966 // members of this anonymous struct/union type, because otherwise 1967 // the members could be injected twice: once by DeclContext when it 1968 // builds its lookup table, and once by 1969 // InjectAnonymousStructOrUnionMembers. 1970 Record->setAnonymousStructOrUnion(true); 1971 1972 if (Invalid) 1973 Anon->setInvalidDecl(); 1974 1975 return Anon; 1976} 1977 1978 1979/// GetNameForDeclarator - Determine the full declaration name for the 1980/// given Declarator. 1981DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 1982 return GetNameFromUnqualifiedId(D.getName()); 1983} 1984 1985/// \brief Retrieves the declaration name from a parsed unqualified-id. 1986DeclarationNameInfo 1987Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1988 DeclarationNameInfo NameInfo; 1989 NameInfo.setLoc(Name.StartLocation); 1990 1991 switch (Name.getKind()) { 1992 1993 case UnqualifiedId::IK_Identifier: 1994 NameInfo.setName(Name.Identifier); 1995 NameInfo.setLoc(Name.StartLocation); 1996 return NameInfo; 1997 1998 case UnqualifiedId::IK_OperatorFunctionId: 1999 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2000 Name.OperatorFunctionId.Operator)); 2001 NameInfo.setLoc(Name.StartLocation); 2002 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2003 = Name.OperatorFunctionId.SymbolLocations[0]; 2004 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2005 = Name.EndLocation.getRawEncoding(); 2006 return NameInfo; 2007 2008 case UnqualifiedId::IK_LiteralOperatorId: 2009 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2010 Name.Identifier)); 2011 NameInfo.setLoc(Name.StartLocation); 2012 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2013 return NameInfo; 2014 2015 case UnqualifiedId::IK_ConversionFunctionId: { 2016 TypeSourceInfo *TInfo; 2017 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2018 if (Ty.isNull()) 2019 return DeclarationNameInfo(); 2020 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2021 Context.getCanonicalType(Ty))); 2022 NameInfo.setLoc(Name.StartLocation); 2023 NameInfo.setNamedTypeInfo(TInfo); 2024 return NameInfo; 2025 } 2026 2027 case UnqualifiedId::IK_ConstructorName: { 2028 TypeSourceInfo *TInfo; 2029 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2030 if (Ty.isNull()) 2031 return DeclarationNameInfo(); 2032 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2033 Context.getCanonicalType(Ty))); 2034 NameInfo.setLoc(Name.StartLocation); 2035 NameInfo.setNamedTypeInfo(TInfo); 2036 return NameInfo; 2037 } 2038 2039 case UnqualifiedId::IK_ConstructorTemplateId: { 2040 // In well-formed code, we can only have a constructor 2041 // template-id that refers to the current context, so go there 2042 // to find the actual type being constructed. 2043 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2044 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2045 return DeclarationNameInfo(); 2046 2047 // Determine the type of the class being constructed. 2048 QualType CurClassType = Context.getTypeDeclType(CurClass); 2049 2050 // FIXME: Check two things: that the template-id names the same type as 2051 // CurClassType, and that the template-id does not occur when the name 2052 // was qualified. 2053 2054 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2055 Context.getCanonicalType(CurClassType))); 2056 NameInfo.setLoc(Name.StartLocation); 2057 // FIXME: should we retrieve TypeSourceInfo? 2058 NameInfo.setNamedTypeInfo(0); 2059 return NameInfo; 2060 } 2061 2062 case UnqualifiedId::IK_DestructorName: { 2063 TypeSourceInfo *TInfo; 2064 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2065 if (Ty.isNull()) 2066 return DeclarationNameInfo(); 2067 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2068 Context.getCanonicalType(Ty))); 2069 NameInfo.setLoc(Name.StartLocation); 2070 NameInfo.setNamedTypeInfo(TInfo); 2071 return NameInfo; 2072 } 2073 2074 case UnqualifiedId::IK_TemplateId: { 2075 TemplateName TName 2076 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2077 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2078 return Context.getNameForTemplate(TName, TNameLoc); 2079 } 2080 2081 } // switch (Name.getKind()) 2082 2083 assert(false && "Unknown name kind"); 2084 return DeclarationNameInfo(); 2085} 2086 2087/// isNearlyMatchingFunction - Determine whether the C++ functions 2088/// Declaration and Definition are "nearly" matching. This heuristic 2089/// is used to improve diagnostics in the case where an out-of-line 2090/// function definition doesn't match any declaration within 2091/// the class or namespace. 2092static bool isNearlyMatchingFunction(ASTContext &Context, 2093 FunctionDecl *Declaration, 2094 FunctionDecl *Definition) { 2095 if (Declaration->param_size() != Definition->param_size()) 2096 return false; 2097 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2098 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2099 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2100 2101 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2102 DefParamTy.getNonReferenceType())) 2103 return false; 2104 } 2105 2106 return true; 2107} 2108 2109/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2110/// declarator needs to be rebuilt in the current instantiation. 2111/// Any bits of declarator which appear before the name are valid for 2112/// consideration here. That's specifically the type in the decl spec 2113/// and the base type in any member-pointer chunks. 2114static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2115 DeclarationName Name) { 2116 // The types we specifically need to rebuild are: 2117 // - typenames, typeofs, and decltypes 2118 // - types which will become injected class names 2119 // Of course, we also need to rebuild any type referencing such a 2120 // type. It's safest to just say "dependent", but we call out a 2121 // few cases here. 2122 2123 DeclSpec &DS = D.getMutableDeclSpec(); 2124 switch (DS.getTypeSpecType()) { 2125 case DeclSpec::TST_typename: 2126 case DeclSpec::TST_typeofType: 2127 case DeclSpec::TST_typeofExpr: 2128 case DeclSpec::TST_decltype: { 2129 // Grab the type from the parser. 2130 TypeSourceInfo *TSI = 0; 2131 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2132 if (T.isNull() || !T->isDependentType()) break; 2133 2134 // Make sure there's a type source info. This isn't really much 2135 // of a waste; most dependent types should have type source info 2136 // attached already. 2137 if (!TSI) 2138 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2139 2140 // Rebuild the type in the current instantiation. 2141 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2142 if (!TSI) return true; 2143 2144 // Store the new type back in the decl spec. 2145 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2146 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2147 break; 2148 } 2149 2150 default: 2151 // Nothing to do for these decl specs. 2152 break; 2153 } 2154 2155 // It doesn't matter what order we do this in. 2156 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2157 DeclaratorChunk &Chunk = D.getTypeObject(I); 2158 2159 // The only type information in the declarator which can come 2160 // before the declaration name is the base type of a member 2161 // pointer. 2162 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2163 continue; 2164 2165 // Rebuild the scope specifier in-place. 2166 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2167 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2168 return true; 2169 } 2170 2171 return false; 2172} 2173 2174Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2175 MultiTemplateParamsArg TemplateParamLists, 2176 bool IsFunctionDefinition) { 2177 // TODO: consider using NameInfo for diagnostic. 2178 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2179 DeclarationName Name = NameInfo.getName(); 2180 2181 // All of these full declarators require an identifier. If it doesn't have 2182 // one, the ParsedFreeStandingDeclSpec action should be used. 2183 if (!Name) { 2184 if (!D.isInvalidType()) // Reject this if we think it is valid. 2185 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2186 diag::err_declarator_need_ident) 2187 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2188 return 0; 2189 } 2190 2191 // The scope passed in may not be a decl scope. Zip up the scope tree until 2192 // we find one that is. 2193 while ((S->getFlags() & Scope::DeclScope) == 0 || 2194 (S->getFlags() & Scope::TemplateParamScope) != 0) 2195 S = S->getParent(); 2196 2197 DeclContext *DC = CurContext; 2198 if (D.getCXXScopeSpec().isInvalid()) 2199 D.setInvalidType(); 2200 else if (D.getCXXScopeSpec().isSet()) { 2201 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2202 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2203 if (!DC) { 2204 // If we could not compute the declaration context, it's because the 2205 // declaration context is dependent but does not refer to a class, 2206 // class template, or class template partial specialization. Complain 2207 // and return early, to avoid the coming semantic disaster. 2208 Diag(D.getIdentifierLoc(), 2209 diag::err_template_qualified_declarator_no_match) 2210 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2211 << D.getCXXScopeSpec().getRange(); 2212 return 0; 2213 } 2214 2215 bool IsDependentContext = DC->isDependentContext(); 2216 2217 if (!IsDependentContext && 2218 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2219 return 0; 2220 2221 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2222 Diag(D.getIdentifierLoc(), 2223 diag::err_member_def_undefined_record) 2224 << Name << DC << D.getCXXScopeSpec().getRange(); 2225 D.setInvalidType(); 2226 } 2227 2228 // Check whether we need to rebuild the type of the given 2229 // declaration in the current instantiation. 2230 if (EnteringContext && IsDependentContext && 2231 TemplateParamLists.size() != 0) { 2232 ContextRAII SavedContext(*this, DC); 2233 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2234 D.setInvalidType(); 2235 } 2236 } 2237 2238 NamedDecl *New; 2239 2240 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2241 QualType R = TInfo->getType(); 2242 2243 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2244 ForRedeclaration); 2245 2246 // See if this is a redefinition of a variable in the same scope. 2247 if (!D.getCXXScopeSpec().isSet()) { 2248 bool IsLinkageLookup = false; 2249 2250 // If the declaration we're planning to build will be a function 2251 // or object with linkage, then look for another declaration with 2252 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2253 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2254 /* Do nothing*/; 2255 else if (R->isFunctionType()) { 2256 if (CurContext->isFunctionOrMethod() || 2257 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2258 IsLinkageLookup = true; 2259 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2260 IsLinkageLookup = true; 2261 else if (CurContext->getLookupContext()->isTranslationUnit() && 2262 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2263 IsLinkageLookup = true; 2264 2265 if (IsLinkageLookup) 2266 Previous.clear(LookupRedeclarationWithLinkage); 2267 2268 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2269 } else { // Something like "int foo::x;" 2270 LookupQualifiedName(Previous, DC); 2271 2272 // Don't consider using declarations as previous declarations for 2273 // out-of-line members. 2274 RemoveUsingDecls(Previous); 2275 2276 // C++ 7.3.1.2p2: 2277 // Members (including explicit specializations of templates) of a named 2278 // namespace can also be defined outside that namespace by explicit 2279 // qualification of the name being defined, provided that the entity being 2280 // defined was already declared in the namespace and the definition appears 2281 // after the point of declaration in a namespace that encloses the 2282 // declarations namespace. 2283 // 2284 // Note that we only check the context at this point. We don't yet 2285 // have enough information to make sure that PrevDecl is actually 2286 // the declaration we want to match. For example, given: 2287 // 2288 // class X { 2289 // void f(); 2290 // void f(float); 2291 // }; 2292 // 2293 // void X::f(int) { } // ill-formed 2294 // 2295 // In this case, PrevDecl will point to the overload set 2296 // containing the two f's declared in X, but neither of them 2297 // matches. 2298 2299 // First check whether we named the global scope. 2300 if (isa<TranslationUnitDecl>(DC)) { 2301 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2302 << Name << D.getCXXScopeSpec().getRange(); 2303 } else { 2304 DeclContext *Cur = CurContext; 2305 while (isa<LinkageSpecDecl>(Cur)) 2306 Cur = Cur->getParent(); 2307 if (!Cur->Encloses(DC)) { 2308 // The qualifying scope doesn't enclose the original declaration. 2309 // Emit diagnostic based on current scope. 2310 SourceLocation L = D.getIdentifierLoc(); 2311 SourceRange R = D.getCXXScopeSpec().getRange(); 2312 if (isa<FunctionDecl>(Cur)) 2313 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2314 else 2315 Diag(L, diag::err_invalid_declarator_scope) 2316 << Name << cast<NamedDecl>(DC) << R; 2317 D.setInvalidType(); 2318 } 2319 } 2320 } 2321 2322 if (Previous.isSingleResult() && 2323 Previous.getFoundDecl()->isTemplateParameter()) { 2324 // Maybe we will complain about the shadowed template parameter. 2325 if (!D.isInvalidType()) 2326 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2327 Previous.getFoundDecl())) 2328 D.setInvalidType(); 2329 2330 // Just pretend that we didn't see the previous declaration. 2331 Previous.clear(); 2332 } 2333 2334 // In C++, the previous declaration we find might be a tag type 2335 // (class or enum). In this case, the new declaration will hide the 2336 // tag type. Note that this does does not apply if we're declaring a 2337 // typedef (C++ [dcl.typedef]p4). 2338 if (Previous.isSingleTagDecl() && 2339 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2340 Previous.clear(); 2341 2342 bool Redeclaration = false; 2343 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2344 if (TemplateParamLists.size()) { 2345 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2346 return 0; 2347 } 2348 2349 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2350 } else if (R->isFunctionType()) { 2351 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2352 move(TemplateParamLists), 2353 IsFunctionDefinition, Redeclaration); 2354 } else { 2355 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2356 move(TemplateParamLists), 2357 Redeclaration); 2358 } 2359 2360 if (New == 0) 2361 return 0; 2362 2363 // If this has an identifier and is not an invalid redeclaration or 2364 // function template specialization, add it to the scope stack. 2365 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2366 PushOnScopeChains(New, S); 2367 2368 return New; 2369} 2370 2371/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2372/// types into constant array types in certain situations which would otherwise 2373/// be errors (for GCC compatibility). 2374static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2375 ASTContext &Context, 2376 bool &SizeIsNegative, 2377 llvm::APSInt &Oversized) { 2378 // This method tries to turn a variable array into a constant 2379 // array even when the size isn't an ICE. This is necessary 2380 // for compatibility with code that depends on gcc's buggy 2381 // constant expression folding, like struct {char x[(int)(char*)2];} 2382 SizeIsNegative = false; 2383 Oversized = 0; 2384 2385 if (T->isDependentType()) 2386 return QualType(); 2387 2388 QualifierCollector Qs; 2389 const Type *Ty = Qs.strip(T); 2390 2391 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2392 QualType Pointee = PTy->getPointeeType(); 2393 QualType FixedType = 2394 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2395 Oversized); 2396 if (FixedType.isNull()) return FixedType; 2397 FixedType = Context.getPointerType(FixedType); 2398 return Qs.apply(FixedType); 2399 } 2400 2401 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2402 if (!VLATy) 2403 return QualType(); 2404 // FIXME: We should probably handle this case 2405 if (VLATy->getElementType()->isVariablyModifiedType()) 2406 return QualType(); 2407 2408 Expr::EvalResult EvalResult; 2409 if (!VLATy->getSizeExpr() || 2410 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2411 !EvalResult.Val.isInt()) 2412 return QualType(); 2413 2414 // Check whether the array size is negative. 2415 llvm::APSInt &Res = EvalResult.Val.getInt(); 2416 if (Res.isSigned() && Res.isNegative()) { 2417 SizeIsNegative = true; 2418 return QualType(); 2419 } 2420 2421 // Check whether the array is too large to be addressed. 2422 unsigned ActiveSizeBits 2423 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2424 Res); 2425 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2426 Oversized = Res; 2427 return QualType(); 2428 } 2429 2430 return Context.getConstantArrayType(VLATy->getElementType(), 2431 Res, ArrayType::Normal, 0); 2432} 2433 2434/// \brief Register the given locally-scoped external C declaration so 2435/// that it can be found later for redeclarations 2436void 2437Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2438 const LookupResult &Previous, 2439 Scope *S) { 2440 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2441 "Decl is not a locally-scoped decl!"); 2442 // Note that we have a locally-scoped external with this name. 2443 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2444 2445 if (!Previous.isSingleResult()) 2446 return; 2447 2448 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2449 2450 // If there was a previous declaration of this variable, it may be 2451 // in our identifier chain. Update the identifier chain with the new 2452 // declaration. 2453 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2454 // The previous declaration was found on the identifer resolver 2455 // chain, so remove it from its scope. 2456 while (S && !S->isDeclScope(PrevDecl)) 2457 S = S->getParent(); 2458 2459 if (S) 2460 S->RemoveDecl(PrevDecl); 2461 } 2462} 2463 2464/// \brief Diagnose function specifiers on a declaration of an identifier that 2465/// does not identify a function. 2466void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2467 // FIXME: We should probably indicate the identifier in question to avoid 2468 // confusion for constructs like "inline int a(), b;" 2469 if (D.getDeclSpec().isInlineSpecified()) 2470 Diag(D.getDeclSpec().getInlineSpecLoc(), 2471 diag::err_inline_non_function); 2472 2473 if (D.getDeclSpec().isVirtualSpecified()) 2474 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2475 diag::err_virtual_non_function); 2476 2477 if (D.getDeclSpec().isExplicitSpecified()) 2478 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2479 diag::err_explicit_non_function); 2480} 2481 2482NamedDecl* 2483Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2484 QualType R, TypeSourceInfo *TInfo, 2485 LookupResult &Previous, bool &Redeclaration) { 2486 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2487 if (D.getCXXScopeSpec().isSet()) { 2488 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2489 << D.getCXXScopeSpec().getRange(); 2490 D.setInvalidType(); 2491 // Pretend we didn't see the scope specifier. 2492 DC = CurContext; 2493 Previous.clear(); 2494 } 2495 2496 if (getLangOptions().CPlusPlus) { 2497 // Check that there are no default arguments (C++ only). 2498 CheckExtraCXXDefaultArguments(D); 2499 } 2500 2501 DiagnoseFunctionSpecifiers(D); 2502 2503 if (D.getDeclSpec().isThreadSpecified()) 2504 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2505 2506 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2507 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2508 << D.getName().getSourceRange(); 2509 return 0; 2510 } 2511 2512 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2513 if (!NewTD) return 0; 2514 2515 // Handle attributes prior to checking for duplicates in MergeVarDecl 2516 ProcessDeclAttributes(S, NewTD, D); 2517 2518 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2519 // then it shall have block scope. 2520 // Note that variably modified types must be fixed before merging the decl so 2521 // that redeclarations will match. 2522 QualType T = NewTD->getUnderlyingType(); 2523 if (T->isVariablyModifiedType()) { 2524 setFunctionHasBranchProtectedScope(); 2525 2526 if (S->getFnParent() == 0) { 2527 bool SizeIsNegative; 2528 llvm::APSInt Oversized; 2529 QualType FixedTy = 2530 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2531 Oversized); 2532 if (!FixedTy.isNull()) { 2533 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2534 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2535 } else { 2536 if (SizeIsNegative) 2537 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2538 else if (T->isVariableArrayType()) 2539 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2540 else if (Oversized.getBoolValue()) 2541 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2542 << Oversized.toString(10); 2543 else 2544 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2545 NewTD->setInvalidDecl(); 2546 } 2547 } 2548 } 2549 2550 // Merge the decl with the existing one if appropriate. If the decl is 2551 // in an outer scope, it isn't the same thing. 2552 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2553 if (!Previous.empty()) { 2554 Redeclaration = true; 2555 MergeTypeDefDecl(NewTD, Previous); 2556 } 2557 2558 // If this is the C FILE type, notify the AST context. 2559 if (IdentifierInfo *II = NewTD->getIdentifier()) 2560 if (!NewTD->isInvalidDecl() && 2561 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2562 if (II->isStr("FILE")) 2563 Context.setFILEDecl(NewTD); 2564 else if (II->isStr("jmp_buf")) 2565 Context.setjmp_bufDecl(NewTD); 2566 else if (II->isStr("sigjmp_buf")) 2567 Context.setsigjmp_bufDecl(NewTD); 2568 } 2569 2570 return NewTD; 2571} 2572 2573/// \brief Determines whether the given declaration is an out-of-scope 2574/// previous declaration. 2575/// 2576/// This routine should be invoked when name lookup has found a 2577/// previous declaration (PrevDecl) that is not in the scope where a 2578/// new declaration by the same name is being introduced. If the new 2579/// declaration occurs in a local scope, previous declarations with 2580/// linkage may still be considered previous declarations (C99 2581/// 6.2.2p4-5, C++ [basic.link]p6). 2582/// 2583/// \param PrevDecl the previous declaration found by name 2584/// lookup 2585/// 2586/// \param DC the context in which the new declaration is being 2587/// declared. 2588/// 2589/// \returns true if PrevDecl is an out-of-scope previous declaration 2590/// for a new delcaration with the same name. 2591static bool 2592isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2593 ASTContext &Context) { 2594 if (!PrevDecl) 2595 return 0; 2596 2597 if (!PrevDecl->hasLinkage()) 2598 return false; 2599 2600 if (Context.getLangOptions().CPlusPlus) { 2601 // C++ [basic.link]p6: 2602 // If there is a visible declaration of an entity with linkage 2603 // having the same name and type, ignoring entities declared 2604 // outside the innermost enclosing namespace scope, the block 2605 // scope declaration declares that same entity and receives the 2606 // linkage of the previous declaration. 2607 DeclContext *OuterContext = DC->getLookupContext(); 2608 if (!OuterContext->isFunctionOrMethod()) 2609 // This rule only applies to block-scope declarations. 2610 return false; 2611 else { 2612 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2613 if (PrevOuterContext->isRecord()) 2614 // We found a member function: ignore it. 2615 return false; 2616 else { 2617 // Find the innermost enclosing namespace for the new and 2618 // previous declarations. 2619 while (!OuterContext->isFileContext()) 2620 OuterContext = OuterContext->getParent(); 2621 while (!PrevOuterContext->isFileContext()) 2622 PrevOuterContext = PrevOuterContext->getParent(); 2623 2624 // The previous declaration is in a different namespace, so it 2625 // isn't the same function. 2626 if (OuterContext->getPrimaryContext() != 2627 PrevOuterContext->getPrimaryContext()) 2628 return false; 2629 } 2630 } 2631 } 2632 2633 return true; 2634} 2635 2636static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2637 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2638 if (!SS.isSet()) return; 2639 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2640 SS.getRange()); 2641} 2642 2643NamedDecl* 2644Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2645 QualType R, TypeSourceInfo *TInfo, 2646 LookupResult &Previous, 2647 MultiTemplateParamsArg TemplateParamLists, 2648 bool &Redeclaration) { 2649 DeclarationName Name = GetNameForDeclarator(D).getName(); 2650 2651 // Check that there are no default arguments (C++ only). 2652 if (getLangOptions().CPlusPlus) 2653 CheckExtraCXXDefaultArguments(D); 2654 2655 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2656 assert(SCSpec != DeclSpec::SCS_typedef && 2657 "Parser allowed 'typedef' as storage class VarDecl."); 2658 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2659 if (SCSpec == DeclSpec::SCS_mutable) { 2660 // mutable can only appear on non-static class members, so it's always 2661 // an error here 2662 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2663 D.setInvalidType(); 2664 SC = VarDecl::None; 2665 } 2666 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2667 VarDecl::StorageClass SCAsWritten 2668 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2669 2670 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2671 if (!II) { 2672 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2673 << Name.getAsString(); 2674 return 0; 2675 } 2676 2677 DiagnoseFunctionSpecifiers(D); 2678 2679 if (!DC->isRecord() && S->getFnParent() == 0) { 2680 // C99 6.9p2: The storage-class specifiers auto and register shall not 2681 // appear in the declaration specifiers in an external declaration. 2682 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2683 2684 // If this is a register variable with an asm label specified, then this 2685 // is a GNU extension. 2686 if (SC == VarDecl::Register && D.getAsmLabel()) 2687 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2688 else 2689 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2690 D.setInvalidType(); 2691 } 2692 } 2693 if (DC->isRecord() && !CurContext->isRecord()) { 2694 // This is an out-of-line definition of a static data member. 2695 if (SC == VarDecl::Static) { 2696 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2697 diag::err_static_out_of_line) 2698 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2699 } else if (SC == VarDecl::None) 2700 SC = VarDecl::Static; 2701 } 2702 if (SC == VarDecl::Static) { 2703 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2704 if (RD->isLocalClass()) 2705 Diag(D.getIdentifierLoc(), 2706 diag::err_static_data_member_not_allowed_in_local_class) 2707 << Name << RD->getDeclName(); 2708 } 2709 } 2710 2711 // Match up the template parameter lists with the scope specifier, then 2712 // determine whether we have a template or a template specialization. 2713 bool isExplicitSpecialization = false; 2714 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2715 bool Invalid = false; 2716 if (TemplateParameterList *TemplateParams 2717 = MatchTemplateParametersToScopeSpecifier( 2718 D.getDeclSpec().getSourceRange().getBegin(), 2719 D.getCXXScopeSpec(), 2720 (TemplateParameterList**)TemplateParamLists.get(), 2721 TemplateParamLists.size(), 2722 /*never a friend*/ false, 2723 isExplicitSpecialization, 2724 Invalid)) { 2725 // All but one template parameter lists have been matching. 2726 --NumMatchedTemplateParamLists; 2727 2728 if (TemplateParams->size() > 0) { 2729 // There is no such thing as a variable template. 2730 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2731 << II 2732 << SourceRange(TemplateParams->getTemplateLoc(), 2733 TemplateParams->getRAngleLoc()); 2734 return 0; 2735 } else { 2736 // There is an extraneous 'template<>' for this variable. Complain 2737 // about it, but allow the declaration of the variable. 2738 Diag(TemplateParams->getTemplateLoc(), 2739 diag::err_template_variable_noparams) 2740 << II 2741 << SourceRange(TemplateParams->getTemplateLoc(), 2742 TemplateParams->getRAngleLoc()); 2743 2744 isExplicitSpecialization = true; 2745 } 2746 } 2747 2748 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2749 II, R, TInfo, SC, SCAsWritten); 2750 2751 if (D.isInvalidType() || Invalid) 2752 NewVD->setInvalidDecl(); 2753 2754 SetNestedNameSpecifier(NewVD, D); 2755 2756 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2757 NewVD->setTemplateParameterListsInfo(Context, 2758 NumMatchedTemplateParamLists, 2759 (TemplateParameterList**)TemplateParamLists.release()); 2760 } 2761 2762 if (D.getDeclSpec().isThreadSpecified()) { 2763 if (NewVD->hasLocalStorage()) 2764 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2765 else if (!Context.Target.isTLSSupported()) 2766 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2767 else 2768 NewVD->setThreadSpecified(true); 2769 } 2770 2771 // Set the lexical context. If the declarator has a C++ scope specifier, the 2772 // lexical context will be different from the semantic context. 2773 NewVD->setLexicalDeclContext(CurContext); 2774 2775 // Handle attributes prior to checking for duplicates in MergeVarDecl 2776 ProcessDeclAttributes(S, NewVD, D); 2777 2778 // Handle GNU asm-label extension (encoded as an attribute). 2779 if (Expr *E = (Expr*) D.getAsmLabel()) { 2780 // The parser guarantees this is a string. 2781 StringLiteral *SE = cast<StringLiteral>(E); 2782 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2783 Context, SE->getString())); 2784 } 2785 2786 // Diagnose shadowed variables before filtering for scope. 2787 if (!D.getCXXScopeSpec().isSet()) 2788 CheckShadow(S, NewVD, Previous); 2789 2790 // Don't consider existing declarations that are in a different 2791 // scope and are out-of-semantic-context declarations (if the new 2792 // declaration has linkage). 2793 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2794 2795 // Merge the decl with the existing one if appropriate. 2796 if (!Previous.empty()) { 2797 if (Previous.isSingleResult() && 2798 isa<FieldDecl>(Previous.getFoundDecl()) && 2799 D.getCXXScopeSpec().isSet()) { 2800 // The user tried to define a non-static data member 2801 // out-of-line (C++ [dcl.meaning]p1). 2802 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2803 << D.getCXXScopeSpec().getRange(); 2804 Previous.clear(); 2805 NewVD->setInvalidDecl(); 2806 } 2807 } else if (D.getCXXScopeSpec().isSet()) { 2808 // No previous declaration in the qualifying scope. 2809 Diag(D.getIdentifierLoc(), diag::err_no_member) 2810 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2811 << D.getCXXScopeSpec().getRange(); 2812 NewVD->setInvalidDecl(); 2813 } 2814 2815 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2816 2817 // This is an explicit specialization of a static data member. Check it. 2818 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2819 CheckMemberSpecialization(NewVD, Previous)) 2820 NewVD->setInvalidDecl(); 2821 2822 // attributes declared post-definition are currently ignored 2823 // FIXME: This should be handled in attribute merging, not 2824 // here. 2825 if (Previous.isSingleResult()) { 2826 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2827 if (Def && (Def = Def->getDefinition()) && 2828 Def != NewVD && D.hasAttributes()) { 2829 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2830 Diag(Def->getLocation(), diag::note_previous_definition); 2831 } 2832 } 2833 2834 // If this is a locally-scoped extern C variable, update the map of 2835 // such variables. 2836 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2837 !NewVD->isInvalidDecl()) 2838 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2839 2840 // If there's a #pragma GCC visibility in scope, and this isn't a class 2841 // member, set the visibility of this variable. 2842 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2843 AddPushedVisibilityAttribute(NewVD); 2844 2845 MarkUnusedFileScopedDecl(NewVD); 2846 2847 return NewVD; 2848} 2849 2850/// \brief Diagnose variable or built-in function shadowing. Implements 2851/// -Wshadow. 2852/// 2853/// This method is called whenever a VarDecl is added to a "useful" 2854/// scope. 2855/// 2856/// \param S the scope in which the shadowing name is being declared 2857/// \param R the lookup of the name 2858/// 2859void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2860 // Return if warning is ignored. 2861 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2862 return; 2863 2864 // Don't diagnose declarations at file scope. The scope might not 2865 // have a DeclContext if (e.g.) we're parsing a function prototype. 2866 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2867 if (NewDC && NewDC->isFileContext()) 2868 return; 2869 2870 // Only diagnose if we're shadowing an unambiguous field or variable. 2871 if (R.getResultKind() != LookupResult::Found) 2872 return; 2873 2874 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2875 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2876 return; 2877 2878 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2879 2880 // Only warn about certain kinds of shadowing for class members. 2881 if (NewDC && NewDC->isRecord()) { 2882 // In particular, don't warn about shadowing non-class members. 2883 if (!OldDC->isRecord()) 2884 return; 2885 2886 // TODO: should we warn about static data members shadowing 2887 // static data members from base classes? 2888 2889 // TODO: don't diagnose for inaccessible shadowed members. 2890 // This is hard to do perfectly because we might friend the 2891 // shadowing context, but that's just a false negative. 2892 } 2893 2894 // Determine what kind of declaration we're shadowing. 2895 unsigned Kind; 2896 if (isa<RecordDecl>(OldDC)) { 2897 if (isa<FieldDecl>(ShadowedDecl)) 2898 Kind = 3; // field 2899 else 2900 Kind = 2; // static data member 2901 } else if (OldDC->isFileContext()) 2902 Kind = 1; // global 2903 else 2904 Kind = 0; // local 2905 2906 DeclarationName Name = R.getLookupName(); 2907 2908 // Emit warning and note. 2909 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2910 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2911} 2912 2913/// \brief Check -Wshadow without the advantage of a previous lookup. 2914void Sema::CheckShadow(Scope *S, VarDecl *D) { 2915 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2916 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2917 LookupName(R, S); 2918 CheckShadow(S, D, R); 2919} 2920 2921/// \brief Perform semantic checking on a newly-created variable 2922/// declaration. 2923/// 2924/// This routine performs all of the type-checking required for a 2925/// variable declaration once it has been built. It is used both to 2926/// check variables after they have been parsed and their declarators 2927/// have been translated into a declaration, and to check variables 2928/// that have been instantiated from a template. 2929/// 2930/// Sets NewVD->isInvalidDecl() if an error was encountered. 2931void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2932 LookupResult &Previous, 2933 bool &Redeclaration) { 2934 // If the decl is already known invalid, don't check it. 2935 if (NewVD->isInvalidDecl()) 2936 return; 2937 2938 QualType T = NewVD->getType(); 2939 2940 if (T->isObjCObjectType()) { 2941 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2942 return NewVD->setInvalidDecl(); 2943 } 2944 2945 // Emit an error if an address space was applied to decl with local storage. 2946 // This includes arrays of objects with address space qualifiers, but not 2947 // automatic variables that point to other address spaces. 2948 // ISO/IEC TR 18037 S5.1.2 2949 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2950 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2951 return NewVD->setInvalidDecl(); 2952 } 2953 2954 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2955 && !NewVD->hasAttr<BlocksAttr>()) 2956 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2957 2958 bool isVM = T->isVariablyModifiedType(); 2959 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2960 NewVD->hasAttr<BlocksAttr>()) 2961 setFunctionHasBranchProtectedScope(); 2962 2963 if ((isVM && NewVD->hasLinkage()) || 2964 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2965 bool SizeIsNegative; 2966 llvm::APSInt Oversized; 2967 QualType FixedTy = 2968 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2969 Oversized); 2970 2971 if (FixedTy.isNull() && T->isVariableArrayType()) { 2972 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2973 // FIXME: This won't give the correct result for 2974 // int a[10][n]; 2975 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2976 2977 if (NewVD->isFileVarDecl()) 2978 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2979 << SizeRange; 2980 else if (NewVD->getStorageClass() == VarDecl::Static) 2981 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2982 << SizeRange; 2983 else 2984 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2985 << SizeRange; 2986 return NewVD->setInvalidDecl(); 2987 } 2988 2989 if (FixedTy.isNull()) { 2990 if (NewVD->isFileVarDecl()) 2991 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2992 else 2993 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2994 return NewVD->setInvalidDecl(); 2995 } 2996 2997 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2998 NewVD->setType(FixedTy); 2999 } 3000 3001 if (Previous.empty() && NewVD->isExternC()) { 3002 // Since we did not find anything by this name and we're declaring 3003 // an extern "C" variable, look for a non-visible extern "C" 3004 // declaration with the same name. 3005 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3006 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3007 if (Pos != LocallyScopedExternalDecls.end()) 3008 Previous.addDecl(Pos->second); 3009 } 3010 3011 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3012 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3013 << T; 3014 return NewVD->setInvalidDecl(); 3015 } 3016 3017 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3018 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3019 return NewVD->setInvalidDecl(); 3020 } 3021 3022 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3023 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3024 return NewVD->setInvalidDecl(); 3025 } 3026 3027 // Function pointers and references cannot have qualified function type, only 3028 // function pointer-to-members can do that. 3029 QualType Pointee; 3030 unsigned PtrOrRef = 0; 3031 if (const PointerType *Ptr = T->getAs<PointerType>()) 3032 Pointee = Ptr->getPointeeType(); 3033 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3034 Pointee = Ref->getPointeeType(); 3035 PtrOrRef = 1; 3036 } 3037 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3038 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3039 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3040 << PtrOrRef; 3041 return NewVD->setInvalidDecl(); 3042 } 3043 3044 if (!Previous.empty()) { 3045 Redeclaration = true; 3046 MergeVarDecl(NewVD, Previous); 3047 } 3048} 3049 3050/// \brief Data used with FindOverriddenMethod 3051struct FindOverriddenMethodData { 3052 Sema *S; 3053 CXXMethodDecl *Method; 3054}; 3055 3056/// \brief Member lookup function that determines whether a given C++ 3057/// method overrides a method in a base class, to be used with 3058/// CXXRecordDecl::lookupInBases(). 3059static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3060 CXXBasePath &Path, 3061 void *UserData) { 3062 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3063 3064 FindOverriddenMethodData *Data 3065 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3066 3067 DeclarationName Name = Data->Method->getDeclName(); 3068 3069 // FIXME: Do we care about other names here too? 3070 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3071 // We really want to find the base class destructor here. 3072 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3073 CanQualType CT = Data->S->Context.getCanonicalType(T); 3074 3075 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3076 } 3077 3078 for (Path.Decls = BaseRecord->lookup(Name); 3079 Path.Decls.first != Path.Decls.second; 3080 ++Path.Decls.first) { 3081 NamedDecl *D = *Path.Decls.first; 3082 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3083 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3084 return true; 3085 } 3086 } 3087 3088 return false; 3089} 3090 3091/// AddOverriddenMethods - See if a method overrides any in the base classes, 3092/// and if so, check that it's a valid override and remember it. 3093void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3094 // Look for virtual methods in base classes that this method might override. 3095 CXXBasePaths Paths; 3096 FindOverriddenMethodData Data; 3097 Data.Method = MD; 3098 Data.S = this; 3099 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3100 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3101 E = Paths.found_decls_end(); I != E; ++I) { 3102 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3103 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3104 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3105 !CheckOverridingFunctionAttributes(MD, OldMD)) 3106 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3107 } 3108 } 3109 } 3110} 3111 3112NamedDecl* 3113Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3114 QualType R, TypeSourceInfo *TInfo, 3115 LookupResult &Previous, 3116 MultiTemplateParamsArg TemplateParamLists, 3117 bool IsFunctionDefinition, bool &Redeclaration) { 3118 assert(R.getTypePtr()->isFunctionType()); 3119 3120 // TODO: consider using NameInfo for diagnostic. 3121 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3122 DeclarationName Name = NameInfo.getName(); 3123 FunctionDecl::StorageClass SC = FunctionDecl::None; 3124 switch (D.getDeclSpec().getStorageClassSpec()) { 3125 default: assert(0 && "Unknown storage class!"); 3126 case DeclSpec::SCS_auto: 3127 case DeclSpec::SCS_register: 3128 case DeclSpec::SCS_mutable: 3129 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3130 diag::err_typecheck_sclass_func); 3131 D.setInvalidType(); 3132 break; 3133 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 3134 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 3135 case DeclSpec::SCS_static: { 3136 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 3137 // C99 6.7.1p5: 3138 // The declaration of an identifier for a function that has 3139 // block scope shall have no explicit storage-class specifier 3140 // other than extern 3141 // See also (C++ [dcl.stc]p4). 3142 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3143 diag::err_static_block_func); 3144 SC = FunctionDecl::None; 3145 } else 3146 SC = FunctionDecl::Static; 3147 break; 3148 } 3149 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 3150 } 3151 3152 if (D.getDeclSpec().isThreadSpecified()) 3153 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3154 3155 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3156 bool isInline = D.getDeclSpec().isInlineSpecified(); 3157 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3158 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3159 3160 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3161 FunctionDecl::StorageClass SCAsWritten 3162 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3163 3164 // Check that the return type is not an abstract class type. 3165 // For record types, this is done by the AbstractClassUsageDiagnoser once 3166 // the class has been completely parsed. 3167 if (!DC->isRecord() && 3168 RequireNonAbstractType(D.getIdentifierLoc(), 3169 R->getAs<FunctionType>()->getResultType(), 3170 diag::err_abstract_type_in_decl, 3171 AbstractReturnType)) 3172 D.setInvalidType(); 3173 3174 // Do not allow returning a objc interface by-value. 3175 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3176 Diag(D.getIdentifierLoc(), 3177 diag::err_object_cannot_be_passed_returned_by_value) << 0 3178 << R->getAs<FunctionType>()->getResultType(); 3179 D.setInvalidType(); 3180 } 3181 3182 bool isVirtualOkay = false; 3183 FunctionDecl *NewFD; 3184 3185 if (isFriend) { 3186 // C++ [class.friend]p5 3187 // A function can be defined in a friend declaration of a 3188 // class . . . . Such a function is implicitly inline. 3189 isInline |= IsFunctionDefinition; 3190 } 3191 3192 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3193 // This is a C++ constructor declaration. 3194 assert(DC->isRecord() && 3195 "Constructors can only be declared in a member context"); 3196 3197 R = CheckConstructorDeclarator(D, R, SC); 3198 3199 // Create the new declaration 3200 NewFD = CXXConstructorDecl::Create(Context, 3201 cast<CXXRecordDecl>(DC), 3202 NameInfo, R, TInfo, 3203 isExplicit, isInline, 3204 /*isImplicitlyDeclared=*/false); 3205 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3206 // This is a C++ destructor declaration. 3207 if (DC->isRecord()) { 3208 R = CheckDestructorDeclarator(D, R, SC); 3209 3210 NewFD = CXXDestructorDecl::Create(Context, 3211 cast<CXXRecordDecl>(DC), 3212 NameInfo, R, 3213 isInline, 3214 /*isImplicitlyDeclared=*/false); 3215 NewFD->setTypeSourceInfo(TInfo); 3216 3217 isVirtualOkay = true; 3218 } else { 3219 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3220 3221 // Create a FunctionDecl to satisfy the function definition parsing 3222 // code path. 3223 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3224 Name, R, TInfo, SC, SCAsWritten, isInline, 3225 /*hasPrototype=*/true); 3226 D.setInvalidType(); 3227 } 3228 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3229 if (!DC->isRecord()) { 3230 Diag(D.getIdentifierLoc(), 3231 diag::err_conv_function_not_member); 3232 return 0; 3233 } 3234 3235 CheckConversionDeclarator(D, R, SC); 3236 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3237 NameInfo, R, TInfo, 3238 isInline, isExplicit); 3239 3240 isVirtualOkay = true; 3241 } else if (DC->isRecord()) { 3242 // If the of the function is the same as the name of the record, then this 3243 // must be an invalid constructor that has a return type. 3244 // (The parser checks for a return type and makes the declarator a 3245 // constructor if it has no return type). 3246 // must have an invalid constructor that has a return type 3247 if (Name.getAsIdentifierInfo() && 3248 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3249 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3250 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3251 << SourceRange(D.getIdentifierLoc()); 3252 return 0; 3253 } 3254 3255 bool isStatic = SC == FunctionDecl::Static; 3256 3257 // [class.free]p1: 3258 // Any allocation function for a class T is a static member 3259 // (even if not explicitly declared static). 3260 if (Name.getCXXOverloadedOperator() == OO_New || 3261 Name.getCXXOverloadedOperator() == OO_Array_New) 3262 isStatic = true; 3263 3264 // [class.free]p6 Any deallocation function for a class X is a static member 3265 // (even if not explicitly declared static). 3266 if (Name.getCXXOverloadedOperator() == OO_Delete || 3267 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3268 isStatic = true; 3269 3270 // This is a C++ method declaration. 3271 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3272 NameInfo, R, TInfo, 3273 isStatic, SCAsWritten, isInline); 3274 3275 isVirtualOkay = !isStatic; 3276 } else { 3277 // Determine whether the function was written with a 3278 // prototype. This true when: 3279 // - we're in C++ (where every function has a prototype), 3280 // - there is a prototype in the declarator, or 3281 // - the type R of the function is some kind of typedef or other reference 3282 // to a type name (which eventually refers to a function type). 3283 bool HasPrototype = 3284 getLangOptions().CPlusPlus || 3285 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3286 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3287 3288 NewFD = FunctionDecl::Create(Context, DC, 3289 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3290 HasPrototype); 3291 } 3292 3293 if (D.isInvalidType()) 3294 NewFD->setInvalidDecl(); 3295 3296 SetNestedNameSpecifier(NewFD, D); 3297 3298 // Set the lexical context. If the declarator has a C++ 3299 // scope specifier, or is the object of a friend declaration, the 3300 // lexical context will be different from the semantic context. 3301 NewFD->setLexicalDeclContext(CurContext); 3302 3303 // Match up the template parameter lists with the scope specifier, then 3304 // determine whether we have a template or a template specialization. 3305 FunctionTemplateDecl *FunctionTemplate = 0; 3306 bool isExplicitSpecialization = false; 3307 bool isFunctionTemplateSpecialization = false; 3308 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3309 bool Invalid = false; 3310 if (TemplateParameterList *TemplateParams 3311 = MatchTemplateParametersToScopeSpecifier( 3312 D.getDeclSpec().getSourceRange().getBegin(), 3313 D.getCXXScopeSpec(), 3314 (TemplateParameterList**)TemplateParamLists.get(), 3315 TemplateParamLists.size(), 3316 isFriend, 3317 isExplicitSpecialization, 3318 Invalid)) { 3319 // All but one template parameter lists have been matching. 3320 --NumMatchedTemplateParamLists; 3321 3322 if (TemplateParams->size() > 0) { 3323 // This is a function template 3324 3325 // Check that we can declare a template here. 3326 if (CheckTemplateDeclScope(S, TemplateParams)) 3327 return 0; 3328 3329 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3330 NewFD->getLocation(), 3331 Name, TemplateParams, 3332 NewFD); 3333 FunctionTemplate->setLexicalDeclContext(CurContext); 3334 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3335 } else { 3336 // This is a function template specialization. 3337 isFunctionTemplateSpecialization = true; 3338 3339 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3340 if (isFriend && isFunctionTemplateSpecialization) { 3341 // We want to remove the "template<>", found here. 3342 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3343 3344 // If we remove the template<> and the name is not a 3345 // template-id, we're actually silently creating a problem: 3346 // the friend declaration will refer to an untemplated decl, 3347 // and clearly the user wants a template specialization. So 3348 // we need to insert '<>' after the name. 3349 SourceLocation InsertLoc; 3350 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3351 InsertLoc = D.getName().getSourceRange().getEnd(); 3352 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3353 } 3354 3355 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3356 << Name << RemoveRange 3357 << FixItHint::CreateRemoval(RemoveRange) 3358 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3359 } 3360 } 3361 } 3362 3363 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3364 NewFD->setTemplateParameterListsInfo(Context, 3365 NumMatchedTemplateParamLists, 3366 (TemplateParameterList**)TemplateParamLists.release()); 3367 } 3368 3369 if (Invalid) { 3370 NewFD->setInvalidDecl(); 3371 if (FunctionTemplate) 3372 FunctionTemplate->setInvalidDecl(); 3373 } 3374 3375 // C++ [dcl.fct.spec]p5: 3376 // The virtual specifier shall only be used in declarations of 3377 // nonstatic class member functions that appear within a 3378 // member-specification of a class declaration; see 10.3. 3379 // 3380 if (isVirtual && !NewFD->isInvalidDecl()) { 3381 if (!isVirtualOkay) { 3382 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3383 diag::err_virtual_non_function); 3384 } else if (!CurContext->isRecord()) { 3385 // 'virtual' was specified outside of the class. 3386 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3387 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3388 } else { 3389 // Okay: Add virtual to the method. 3390 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3391 CurClass->setMethodAsVirtual(NewFD); 3392 } 3393 } 3394 3395 // C++ [dcl.fct.spec]p3: 3396 // The inline specifier shall not appear on a block scope function declaration. 3397 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3398 if (CurContext->isFunctionOrMethod()) { 3399 // 'inline' is not allowed on block scope function declaration. 3400 Diag(D.getDeclSpec().getInlineSpecLoc(), 3401 diag::err_inline_declaration_block_scope) << Name 3402 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3403 } 3404 } 3405 3406 // C++ [dcl.fct.spec]p6: 3407 // The explicit specifier shall be used only in the declaration of a 3408 // constructor or conversion function within its class definition; see 12.3.1 3409 // and 12.3.2. 3410 if (isExplicit && !NewFD->isInvalidDecl()) { 3411 if (!CurContext->isRecord()) { 3412 // 'explicit' was specified outside of the class. 3413 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3414 diag::err_explicit_out_of_class) 3415 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3416 } else if (!isa<CXXConstructorDecl>(NewFD) && 3417 !isa<CXXConversionDecl>(NewFD)) { 3418 // 'explicit' was specified on a function that wasn't a constructor 3419 // or conversion function. 3420 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3421 diag::err_explicit_non_ctor_or_conv_function) 3422 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3423 } 3424 } 3425 3426 // Filter out previous declarations that don't match the scope. 3427 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3428 3429 if (isFriend) { 3430 // DC is the namespace in which the function is being declared. 3431 assert((DC->isFileContext() || !Previous.empty()) && 3432 "previously-undeclared friend function being created " 3433 "in a non-namespace context"); 3434 3435 // For now, claim that the objects have no previous declaration. 3436 if (FunctionTemplate) { 3437 FunctionTemplate->setObjectOfFriendDecl(false); 3438 FunctionTemplate->setAccess(AS_public); 3439 } 3440 NewFD->setObjectOfFriendDecl(false); 3441 NewFD->setAccess(AS_public); 3442 } 3443 3444 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3445 !CurContext->isRecord()) { 3446 // C++ [class.static]p1: 3447 // A data or function member of a class may be declared static 3448 // in a class definition, in which case it is a static member of 3449 // the class. 3450 3451 // Complain about the 'static' specifier if it's on an out-of-line 3452 // member function definition. 3453 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3454 diag::err_static_out_of_line) 3455 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3456 } 3457 3458 // Handle GNU asm-label extension (encoded as an attribute). 3459 if (Expr *E = (Expr*) D.getAsmLabel()) { 3460 // The parser guarantees this is a string. 3461 StringLiteral *SE = cast<StringLiteral>(E); 3462 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3463 SE->getString())); 3464 } 3465 3466 // Copy the parameter declarations from the declarator D to the function 3467 // declaration NewFD, if they are available. First scavenge them into Params. 3468 llvm::SmallVector<ParmVarDecl*, 16> Params; 3469 if (D.getNumTypeObjects() > 0) { 3470 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3471 3472 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3473 // function that takes no arguments, not a function that takes a 3474 // single void argument. 3475 // We let through "const void" here because Sema::GetTypeForDeclarator 3476 // already checks for that case. 3477 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3478 FTI.ArgInfo[0].Param && 3479 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3480 // Empty arg list, don't push any params. 3481 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3482 3483 // In C++, the empty parameter-type-list must be spelled "void"; a 3484 // typedef of void is not permitted. 3485 if (getLangOptions().CPlusPlus && 3486 Param->getType().getUnqualifiedType() != Context.VoidTy) 3487 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3488 // FIXME: Leaks decl? 3489 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3490 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3491 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3492 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3493 Param->setDeclContext(NewFD); 3494 Params.push_back(Param); 3495 3496 if (Param->isInvalidDecl()) 3497 NewFD->setInvalidDecl(); 3498 } 3499 } 3500 3501 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3502 // When we're declaring a function with a typedef, typeof, etc as in the 3503 // following example, we'll need to synthesize (unnamed) 3504 // parameters for use in the declaration. 3505 // 3506 // @code 3507 // typedef void fn(int); 3508 // fn f; 3509 // @endcode 3510 3511 // Synthesize a parameter for each argument type. 3512 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3513 AE = FT->arg_type_end(); AI != AE; ++AI) { 3514 ParmVarDecl *Param = 3515 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3516 Params.push_back(Param); 3517 } 3518 } else { 3519 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3520 "Should not need args for typedef of non-prototype fn"); 3521 } 3522 // Finally, we know we have the right number of parameters, install them. 3523 NewFD->setParams(Params.data(), Params.size()); 3524 3525 // If the declarator is a template-id, translate the parser's template 3526 // argument list into our AST format. 3527 bool HasExplicitTemplateArgs = false; 3528 TemplateArgumentListInfo TemplateArgs; 3529 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3530 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3531 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3532 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3533 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3534 TemplateId->getTemplateArgs(), 3535 TemplateId->NumArgs); 3536 translateTemplateArguments(TemplateArgsPtr, 3537 TemplateArgs); 3538 TemplateArgsPtr.release(); 3539 3540 HasExplicitTemplateArgs = true; 3541 3542 if (FunctionTemplate) { 3543 // FIXME: Diagnose function template with explicit template 3544 // arguments. 3545 HasExplicitTemplateArgs = false; 3546 } else if (!isFunctionTemplateSpecialization && 3547 !D.getDeclSpec().isFriendSpecified()) { 3548 // We have encountered something that the user meant to be a 3549 // specialization (because it has explicitly-specified template 3550 // arguments) but that was not introduced with a "template<>" (or had 3551 // too few of them). 3552 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3553 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3554 << FixItHint::CreateInsertion( 3555 D.getDeclSpec().getSourceRange().getBegin(), 3556 "template<> "); 3557 isFunctionTemplateSpecialization = true; 3558 } else { 3559 // "friend void foo<>(int);" is an implicit specialization decl. 3560 isFunctionTemplateSpecialization = true; 3561 } 3562 } else if (isFriend && isFunctionTemplateSpecialization) { 3563 // This combination is only possible in a recovery case; the user 3564 // wrote something like: 3565 // template <> friend void foo(int); 3566 // which we're recovering from as if the user had written: 3567 // friend void foo<>(int); 3568 // Go ahead and fake up a template id. 3569 HasExplicitTemplateArgs = true; 3570 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3571 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3572 } 3573 3574 // If it's a friend (and only if it's a friend), it's possible 3575 // that either the specialized function type or the specialized 3576 // template is dependent, and therefore matching will fail. In 3577 // this case, don't check the specialization yet. 3578 if (isFunctionTemplateSpecialization && isFriend && 3579 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3580 assert(HasExplicitTemplateArgs && 3581 "friend function specialization without template args"); 3582 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3583 Previous)) 3584 NewFD->setInvalidDecl(); 3585 } else if (isFunctionTemplateSpecialization) { 3586 if (CheckFunctionTemplateSpecialization(NewFD, 3587 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3588 Previous)) 3589 NewFD->setInvalidDecl(); 3590 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3591 if (CheckMemberSpecialization(NewFD, Previous)) 3592 NewFD->setInvalidDecl(); 3593 } 3594 3595 // Perform semantic checking on the function declaration. 3596 bool OverloadableAttrRequired = false; // FIXME: HACK! 3597 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3598 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3599 3600 assert((NewFD->isInvalidDecl() || !Redeclaration || 3601 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3602 "previous declaration set still overloaded"); 3603 3604 NamedDecl *PrincipalDecl = (FunctionTemplate 3605 ? cast<NamedDecl>(FunctionTemplate) 3606 : NewFD); 3607 3608 if (isFriend && Redeclaration) { 3609 AccessSpecifier Access = AS_public; 3610 if (!NewFD->isInvalidDecl()) 3611 Access = NewFD->getPreviousDeclaration()->getAccess(); 3612 3613 NewFD->setAccess(Access); 3614 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3615 3616 PrincipalDecl->setObjectOfFriendDecl(true); 3617 } 3618 3619 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3620 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3621 PrincipalDecl->setNonMemberOperator(); 3622 3623 // If we have a function template, check the template parameter 3624 // list. This will check and merge default template arguments. 3625 if (FunctionTemplate) { 3626 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3627 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3628 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3629 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3630 : TPC_FunctionTemplate); 3631 } 3632 3633 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3634 // Fake up an access specifier if it's supposed to be a class member. 3635 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3636 NewFD->setAccess(AS_public); 3637 3638 // An out-of-line member function declaration must also be a 3639 // definition (C++ [dcl.meaning]p1). 3640 // Note that this is not the case for explicit specializations of 3641 // function templates or member functions of class templates, per 3642 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3643 // for compatibility with old SWIG code which likes to generate them. 3644 if (!IsFunctionDefinition && !isFriend && 3645 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3646 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3647 << D.getCXXScopeSpec().getRange(); 3648 } 3649 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3650 // The user tried to provide an out-of-line definition for a 3651 // function that is a member of a class or namespace, but there 3652 // was no such member function declared (C++ [class.mfct]p2, 3653 // C++ [namespace.memdef]p2). For example: 3654 // 3655 // class X { 3656 // void f() const; 3657 // }; 3658 // 3659 // void X::f() { } // ill-formed 3660 // 3661 // Complain about this problem, and attempt to suggest close 3662 // matches (e.g., those that differ only in cv-qualifiers and 3663 // whether the parameter types are references). 3664 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3665 << Name << DC << D.getCXXScopeSpec().getRange(); 3666 NewFD->setInvalidDecl(); 3667 3668 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3669 ForRedeclaration); 3670 LookupQualifiedName(Prev, DC); 3671 assert(!Prev.isAmbiguous() && 3672 "Cannot have an ambiguity in previous-declaration lookup"); 3673 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3674 Func != FuncEnd; ++Func) { 3675 if (isa<FunctionDecl>(*Func) && 3676 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3677 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3678 } 3679 } 3680 } 3681 3682 // Handle attributes. We need to have merged decls when handling attributes 3683 // (for example to check for conflicts, etc). 3684 // FIXME: This needs to happen before we merge declarations. Then, 3685 // let attribute merging cope with attribute conflicts. 3686 ProcessDeclAttributes(S, NewFD, D); 3687 3688 // attributes declared post-definition are currently ignored 3689 // FIXME: This should happen during attribute merging 3690 if (Redeclaration && Previous.isSingleResult()) { 3691 const FunctionDecl *Def; 3692 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3693 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3694 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3695 Diag(Def->getLocation(), diag::note_previous_definition); 3696 } 3697 } 3698 3699 AddKnownFunctionAttributes(NewFD); 3700 3701 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3702 // If a function name is overloadable in C, then every function 3703 // with that name must be marked "overloadable". 3704 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3705 << Redeclaration << NewFD; 3706 if (!Previous.empty()) 3707 Diag(Previous.getRepresentativeDecl()->getLocation(), 3708 diag::note_attribute_overloadable_prev_overload); 3709 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3710 } 3711 3712 if (NewFD->hasAttr<OverloadableAttr>() && 3713 !NewFD->getType()->getAs<FunctionProtoType>()) { 3714 Diag(NewFD->getLocation(), 3715 diag::err_attribute_overloadable_no_prototype) 3716 << NewFD; 3717 3718 // Turn this into a variadic function with no parameters. 3719 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3720 QualType R = Context.getFunctionType(FT->getResultType(), 3721 0, 0, true, 0, false, false, 0, 0, 3722 FT->getExtInfo()); 3723 NewFD->setType(R); 3724 } 3725 3726 // If there's a #pragma GCC visibility in scope, and this isn't a class 3727 // member, set the visibility of this function. 3728 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3729 AddPushedVisibilityAttribute(NewFD); 3730 3731 // If this is a locally-scoped extern C function, update the 3732 // map of such names. 3733 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3734 && !NewFD->isInvalidDecl()) 3735 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3736 3737 // Set this FunctionDecl's range up to the right paren. 3738 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3739 3740 if (FunctionTemplate && NewFD->isInvalidDecl()) 3741 FunctionTemplate->setInvalidDecl(); 3742 3743 if (FunctionTemplate) 3744 return FunctionTemplate; 3745 3746 MarkUnusedFileScopedDecl(NewFD); 3747 3748 return NewFD; 3749} 3750 3751/// \brief Perform semantic checking of a new function declaration. 3752/// 3753/// Performs semantic analysis of the new function declaration 3754/// NewFD. This routine performs all semantic checking that does not 3755/// require the actual declarator involved in the declaration, and is 3756/// used both for the declaration of functions as they are parsed 3757/// (called via ActOnDeclarator) and for the declaration of functions 3758/// that have been instantiated via C++ template instantiation (called 3759/// via InstantiateDecl). 3760/// 3761/// \param IsExplicitSpecialiation whether this new function declaration is 3762/// an explicit specialization of the previous declaration. 3763/// 3764/// This sets NewFD->isInvalidDecl() to true if there was an error. 3765void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3766 LookupResult &Previous, 3767 bool IsExplicitSpecialization, 3768 bool &Redeclaration, 3769 bool &OverloadableAttrRequired) { 3770 // If NewFD is already known erroneous, don't do any of this checking. 3771 if (NewFD->isInvalidDecl()) { 3772 // If this is a class member, mark the class invalid immediately. 3773 // This avoids some consistency errors later. 3774 if (isa<CXXMethodDecl>(NewFD)) 3775 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3776 3777 return; 3778 } 3779 3780 if (NewFD->getResultType()->isVariablyModifiedType()) { 3781 // Functions returning a variably modified type violate C99 6.7.5.2p2 3782 // because all functions have linkage. 3783 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3784 return NewFD->setInvalidDecl(); 3785 } 3786 3787 if (NewFD->isMain()) 3788 CheckMain(NewFD); 3789 3790 // Check for a previous declaration of this name. 3791 if (Previous.empty() && NewFD->isExternC()) { 3792 // Since we did not find anything by this name and we're declaring 3793 // an extern "C" function, look for a non-visible extern "C" 3794 // declaration with the same name. 3795 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3796 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3797 if (Pos != LocallyScopedExternalDecls.end()) 3798 Previous.addDecl(Pos->second); 3799 } 3800 3801 // Merge or overload the declaration with an existing declaration of 3802 // the same name, if appropriate. 3803 if (!Previous.empty()) { 3804 // Determine whether NewFD is an overload of PrevDecl or 3805 // a declaration that requires merging. If it's an overload, 3806 // there's no more work to do here; we'll just add the new 3807 // function to the scope. 3808 3809 NamedDecl *OldDecl = 0; 3810 if (!AllowOverloadingOfFunction(Previous, Context)) { 3811 Redeclaration = true; 3812 OldDecl = Previous.getFoundDecl(); 3813 } else { 3814 if (!getLangOptions().CPlusPlus) 3815 OverloadableAttrRequired = true; 3816 3817 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3818 /*NewIsUsingDecl*/ false)) { 3819 case Ovl_Match: 3820 Redeclaration = true; 3821 break; 3822 3823 case Ovl_NonFunction: 3824 Redeclaration = true; 3825 break; 3826 3827 case Ovl_Overload: 3828 Redeclaration = false; 3829 break; 3830 } 3831 } 3832 3833 if (Redeclaration) { 3834 // NewFD and OldDecl represent declarations that need to be 3835 // merged. 3836 if (MergeFunctionDecl(NewFD, OldDecl)) 3837 return NewFD->setInvalidDecl(); 3838 3839 Previous.clear(); 3840 Previous.addDecl(OldDecl); 3841 3842 if (FunctionTemplateDecl *OldTemplateDecl 3843 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3844 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3845 FunctionTemplateDecl *NewTemplateDecl 3846 = NewFD->getDescribedFunctionTemplate(); 3847 assert(NewTemplateDecl && "Template/non-template mismatch"); 3848 if (CXXMethodDecl *Method 3849 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3850 Method->setAccess(OldTemplateDecl->getAccess()); 3851 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3852 } 3853 3854 // If this is an explicit specialization of a member that is a function 3855 // template, mark it as a member specialization. 3856 if (IsExplicitSpecialization && 3857 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3858 NewTemplateDecl->setMemberSpecialization(); 3859 assert(OldTemplateDecl->isMemberSpecialization()); 3860 } 3861 } else { 3862 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3863 NewFD->setAccess(OldDecl->getAccess()); 3864 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3865 } 3866 } 3867 } 3868 3869 // Semantic checking for this function declaration (in isolation). 3870 if (getLangOptions().CPlusPlus) { 3871 // C++-specific checks. 3872 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3873 CheckConstructor(Constructor); 3874 } else if (CXXDestructorDecl *Destructor = 3875 dyn_cast<CXXDestructorDecl>(NewFD)) { 3876 CXXRecordDecl *Record = Destructor->getParent(); 3877 QualType ClassType = Context.getTypeDeclType(Record); 3878 3879 // FIXME: Shouldn't we be able to perform this check even when the class 3880 // type is dependent? Both gcc and edg can handle that. 3881 if (!ClassType->isDependentType()) { 3882 DeclarationName Name 3883 = Context.DeclarationNames.getCXXDestructorName( 3884 Context.getCanonicalType(ClassType)); 3885// NewFD->getDeclName().dump(); 3886// Name.dump(); 3887 if (NewFD->getDeclName() != Name) { 3888 Diag(NewFD->getLocation(), diag::err_destructor_name); 3889 return NewFD->setInvalidDecl(); 3890 } 3891 } 3892 3893 Record->setUserDeclaredDestructor(true); 3894 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3895 // user-defined destructor. 3896 Record->setPOD(false); 3897 3898 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3899 // declared destructor. 3900 // FIXME: C++0x: don't do this for "= default" destructors 3901 Record->setHasTrivialDestructor(false); 3902 } else if (CXXConversionDecl *Conversion 3903 = dyn_cast<CXXConversionDecl>(NewFD)) { 3904 ActOnConversionDeclarator(Conversion); 3905 } 3906 3907 // Find any virtual functions that this function overrides. 3908 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3909 if (!Method->isFunctionTemplateSpecialization() && 3910 !Method->getDescribedFunctionTemplate()) 3911 AddOverriddenMethods(Method->getParent(), Method); 3912 } 3913 3914 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3915 if (NewFD->isOverloadedOperator() && 3916 CheckOverloadedOperatorDeclaration(NewFD)) 3917 return NewFD->setInvalidDecl(); 3918 3919 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3920 if (NewFD->getLiteralIdentifier() && 3921 CheckLiteralOperatorDeclaration(NewFD)) 3922 return NewFD->setInvalidDecl(); 3923 3924 // In C++, check default arguments now that we have merged decls. Unless 3925 // the lexical context is the class, because in this case this is done 3926 // during delayed parsing anyway. 3927 if (!CurContext->isRecord()) 3928 CheckCXXDefaultArguments(NewFD); 3929 } 3930} 3931 3932void Sema::CheckMain(FunctionDecl* FD) { 3933 // C++ [basic.start.main]p3: A program that declares main to be inline 3934 // or static is ill-formed. 3935 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3936 // shall not appear in a declaration of main. 3937 // static main is not an error under C99, but we should warn about it. 3938 bool isInline = FD->isInlineSpecified(); 3939 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3940 if (isInline || isStatic) { 3941 unsigned diagID = diag::warn_unusual_main_decl; 3942 if (isInline || getLangOptions().CPlusPlus) 3943 diagID = diag::err_unusual_main_decl; 3944 3945 int which = isStatic + (isInline << 1) - 1; 3946 Diag(FD->getLocation(), diagID) << which; 3947 } 3948 3949 QualType T = FD->getType(); 3950 assert(T->isFunctionType() && "function decl is not of function type"); 3951 const FunctionType* FT = T->getAs<FunctionType>(); 3952 3953 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3954 // TODO: add a replacement fixit to turn the return type into 'int'. 3955 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3956 FD->setInvalidDecl(true); 3957 } 3958 3959 // Treat protoless main() as nullary. 3960 if (isa<FunctionNoProtoType>(FT)) return; 3961 3962 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3963 unsigned nparams = FTP->getNumArgs(); 3964 assert(FD->getNumParams() == nparams); 3965 3966 bool HasExtraParameters = (nparams > 3); 3967 3968 // Darwin passes an undocumented fourth argument of type char**. If 3969 // other platforms start sprouting these, the logic below will start 3970 // getting shifty. 3971 if (nparams == 4 && 3972 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3973 HasExtraParameters = false; 3974 3975 if (HasExtraParameters) { 3976 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3977 FD->setInvalidDecl(true); 3978 nparams = 3; 3979 } 3980 3981 // FIXME: a lot of the following diagnostics would be improved 3982 // if we had some location information about types. 3983 3984 QualType CharPP = 3985 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3986 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3987 3988 for (unsigned i = 0; i < nparams; ++i) { 3989 QualType AT = FTP->getArgType(i); 3990 3991 bool mismatch = true; 3992 3993 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3994 mismatch = false; 3995 else if (Expected[i] == CharPP) { 3996 // As an extension, the following forms are okay: 3997 // char const ** 3998 // char const * const * 3999 // char * const * 4000 4001 QualifierCollector qs; 4002 const PointerType* PT; 4003 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4004 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4005 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4006 qs.removeConst(); 4007 mismatch = !qs.empty(); 4008 } 4009 } 4010 4011 if (mismatch) { 4012 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4013 // TODO: suggest replacing given type with expected type 4014 FD->setInvalidDecl(true); 4015 } 4016 } 4017 4018 if (nparams == 1 && !FD->isInvalidDecl()) { 4019 Diag(FD->getLocation(), diag::warn_main_one_arg); 4020 } 4021} 4022 4023bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4024 // FIXME: Need strict checking. In C89, we need to check for 4025 // any assignment, increment, decrement, function-calls, or 4026 // commas outside of a sizeof. In C99, it's the same list, 4027 // except that the aforementioned are allowed in unevaluated 4028 // expressions. Everything else falls under the 4029 // "may accept other forms of constant expressions" exception. 4030 // (We never end up here for C++, so the constant expression 4031 // rules there don't matter.) 4032 if (Init->isConstantInitializer(Context, false)) 4033 return false; 4034 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4035 << Init->getSourceRange(); 4036 return true; 4037} 4038 4039void Sema::AddInitializerToDecl(Decl *dcl, ExprArg init) { 4040 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 4041} 4042 4043/// AddInitializerToDecl - Adds the initializer Init to the 4044/// declaration dcl. If DirectInit is true, this is C++ direct 4045/// initialization rather than copy initialization. 4046void Sema::AddInitializerToDecl(Decl *RealDecl, ExprArg init, bool DirectInit) { 4047 // If there is no declaration, there was an error parsing it. Just ignore 4048 // the initializer. 4049 if (RealDecl == 0) 4050 return; 4051 4052 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4053 // With declarators parsed the way they are, the parser cannot 4054 // distinguish between a normal initializer and a pure-specifier. 4055 // Thus this grotesque test. 4056 IntegerLiteral *IL; 4057 Expr *Init = static_cast<Expr *>(init.get()); 4058 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4059 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4060 CheckPureMethod(Method, Init->getSourceRange()); 4061 else { 4062 Diag(Method->getLocation(), diag::err_member_function_initialization) 4063 << Method->getDeclName() << Init->getSourceRange(); 4064 Method->setInvalidDecl(); 4065 } 4066 return; 4067 } 4068 4069 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4070 if (!VDecl) { 4071 if (getLangOptions().CPlusPlus && 4072 RealDecl->getLexicalDeclContext()->isRecord() && 4073 isa<NamedDecl>(RealDecl)) 4074 Diag(RealDecl->getLocation(), diag::err_member_initialization) 4075 << cast<NamedDecl>(RealDecl)->getDeclName(); 4076 else 4077 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4078 RealDecl->setInvalidDecl(); 4079 return; 4080 } 4081 4082 // A definition must end up with a complete type, which means it must be 4083 // complete with the restriction that an array type might be completed by the 4084 // initializer; note that later code assumes this restriction. 4085 QualType BaseDeclType = VDecl->getType(); 4086 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4087 BaseDeclType = Array->getElementType(); 4088 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4089 diag::err_typecheck_decl_incomplete_type)) { 4090 RealDecl->setInvalidDecl(); 4091 return; 4092 } 4093 4094 // The variable can not have an abstract class type. 4095 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4096 diag::err_abstract_type_in_decl, 4097 AbstractVariableType)) 4098 VDecl->setInvalidDecl(); 4099 4100 const VarDecl *Def; 4101 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4102 Diag(VDecl->getLocation(), diag::err_redefinition) 4103 << VDecl->getDeclName(); 4104 Diag(Def->getLocation(), diag::note_previous_definition); 4105 VDecl->setInvalidDecl(); 4106 return; 4107 } 4108 4109 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4110 setFunctionHasBranchProtectedScope(); 4111 4112 // Take ownership of the expression, now that we're sure we have somewhere 4113 // to put it. 4114 Expr *Init = init.takeAs<Expr>(); 4115 assert(Init && "missing initializer"); 4116 4117 // Capture the variable that is being initialized and the style of 4118 // initialization. 4119 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4120 4121 // FIXME: Poor source location information. 4122 InitializationKind Kind 4123 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4124 Init->getLocStart(), 4125 Init->getLocEnd()) 4126 : InitializationKind::CreateCopy(VDecl->getLocation(), 4127 Init->getLocStart()); 4128 4129 // Get the decls type and save a reference for later, since 4130 // CheckInitializerTypes may change it. 4131 QualType DclT = VDecl->getType(), SavT = DclT; 4132 if (VDecl->isBlockVarDecl()) { 4133 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4134 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4135 VDecl->setInvalidDecl(); 4136 } else if (!VDecl->isInvalidDecl()) { 4137 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4138 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4139 MultiExprArg(*this, &Init, 1), 4140 &DclT); 4141 if (Result.isInvalid()) { 4142 VDecl->setInvalidDecl(); 4143 return; 4144 } 4145 4146 Init = Result.takeAs<Expr>(); 4147 4148 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4149 // Don't check invalid declarations to avoid emitting useless diagnostics. 4150 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4151 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 4152 CheckForConstantInitializer(Init, DclT); 4153 } 4154 } 4155 } else if (VDecl->isStaticDataMember() && 4156 VDecl->getLexicalDeclContext()->isRecord()) { 4157 // This is an in-class initialization for a static data member, e.g., 4158 // 4159 // struct S { 4160 // static const int value = 17; 4161 // }; 4162 4163 // Attach the initializer 4164 VDecl->setInit(Init); 4165 4166 // C++ [class.mem]p4: 4167 // A member-declarator can contain a constant-initializer only 4168 // if it declares a static member (9.4) of const integral or 4169 // const enumeration type, see 9.4.2. 4170 QualType T = VDecl->getType(); 4171 if (!T->isDependentType() && 4172 (!Context.getCanonicalType(T).isConstQualified() || 4173 !T->isIntegralOrEnumerationType())) { 4174 Diag(VDecl->getLocation(), diag::err_member_initialization) 4175 << VDecl->getDeclName() << Init->getSourceRange(); 4176 VDecl->setInvalidDecl(); 4177 } else { 4178 // C++ [class.static.data]p4: 4179 // If a static data member is of const integral or const 4180 // enumeration type, its declaration in the class definition 4181 // can specify a constant-initializer which shall be an 4182 // integral constant expression (5.19). 4183 if (!Init->isTypeDependent() && 4184 !Init->getType()->isIntegralOrEnumerationType()) { 4185 // We have a non-dependent, non-integral or enumeration type. 4186 Diag(Init->getSourceRange().getBegin(), 4187 diag::err_in_class_initializer_non_integral_type) 4188 << Init->getType() << Init->getSourceRange(); 4189 VDecl->setInvalidDecl(); 4190 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4191 // Check whether the expression is a constant expression. 4192 llvm::APSInt Value; 4193 SourceLocation Loc; 4194 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4195 Diag(Loc, diag::err_in_class_initializer_non_constant) 4196 << Init->getSourceRange(); 4197 VDecl->setInvalidDecl(); 4198 } else if (!VDecl->getType()->isDependentType()) 4199 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4200 } 4201 } 4202 } else if (VDecl->isFileVarDecl()) { 4203 if (VDecl->getStorageClass() == VarDecl::Extern && 4204 (!getLangOptions().CPlusPlus || 4205 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4206 Diag(VDecl->getLocation(), diag::warn_extern_init); 4207 if (!VDecl->isInvalidDecl()) { 4208 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4209 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4210 MultiExprArg(*this, &Init, 1), 4211 &DclT); 4212 if (Result.isInvalid()) { 4213 VDecl->setInvalidDecl(); 4214 return; 4215 } 4216 4217 Init = Result.takeAs<Expr>(); 4218 } 4219 4220 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4221 // Don't check invalid declarations to avoid emitting useless diagnostics. 4222 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4223 // C99 6.7.8p4. All file scoped initializers need to be constant. 4224 CheckForConstantInitializer(Init, DclT); 4225 } 4226 } 4227 // If the type changed, it means we had an incomplete type that was 4228 // completed by the initializer. For example: 4229 // int ary[] = { 1, 3, 5 }; 4230 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4231 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4232 VDecl->setType(DclT); 4233 Init->setType(DclT); 4234 } 4235 4236 Init = MaybeCreateCXXExprWithTemporaries(Init); 4237 // Attach the initializer to the decl. 4238 VDecl->setInit(Init); 4239 4240 if (getLangOptions().CPlusPlus) { 4241 if (!VDecl->isInvalidDecl() && 4242 !VDecl->getDeclContext()->isDependentContext() && 4243 VDecl->hasGlobalStorage() && 4244 !Init->isConstantInitializer(Context, 4245 VDecl->getType()->isReferenceType())) 4246 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4247 << Init->getSourceRange(); 4248 4249 // Make sure we mark the destructor as used if necessary. 4250 QualType InitType = VDecl->getType(); 4251 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4252 InitType = Context.getBaseElementType(Array); 4253 if (const RecordType *Record = InitType->getAs<RecordType>()) 4254 FinalizeVarWithDestructor(VDecl, Record); 4255 } 4256 4257 return; 4258} 4259 4260/// ActOnInitializerError - Given that there was an error parsing an 4261/// initializer for the given declaration, try to return to some form 4262/// of sanity. 4263void Sema::ActOnInitializerError(Decl *D) { 4264 // Our main concern here is re-establishing invariants like "a 4265 // variable's type is either dependent or complete". 4266 if (!D || D->isInvalidDecl()) return; 4267 4268 VarDecl *VD = dyn_cast<VarDecl>(D); 4269 if (!VD) return; 4270 4271 QualType Ty = VD->getType(); 4272 if (Ty->isDependentType()) return; 4273 4274 // Require a complete type. 4275 if (RequireCompleteType(VD->getLocation(), 4276 Context.getBaseElementType(Ty), 4277 diag::err_typecheck_decl_incomplete_type)) { 4278 VD->setInvalidDecl(); 4279 return; 4280 } 4281 4282 // Require an abstract type. 4283 if (RequireNonAbstractType(VD->getLocation(), Ty, 4284 diag::err_abstract_type_in_decl, 4285 AbstractVariableType)) { 4286 VD->setInvalidDecl(); 4287 return; 4288 } 4289 4290 // Don't bother complaining about constructors or destructors, 4291 // though. 4292} 4293 4294void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4295 bool TypeContainsUndeducedAuto) { 4296 // If there is no declaration, there was an error parsing it. Just ignore it. 4297 if (RealDecl == 0) 4298 return; 4299 4300 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4301 QualType Type = Var->getType(); 4302 4303 // C++0x [dcl.spec.auto]p3 4304 if (TypeContainsUndeducedAuto) { 4305 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4306 << Var->getDeclName() << Type; 4307 Var->setInvalidDecl(); 4308 return; 4309 } 4310 4311 switch (Var->isThisDeclarationADefinition()) { 4312 case VarDecl::Definition: 4313 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4314 break; 4315 4316 // We have an out-of-line definition of a static data member 4317 // that has an in-class initializer, so we type-check this like 4318 // a declaration. 4319 // 4320 // Fall through 4321 4322 case VarDecl::DeclarationOnly: 4323 // It's only a declaration. 4324 4325 // Block scope. C99 6.7p7: If an identifier for an object is 4326 // declared with no linkage (C99 6.2.2p6), the type for the 4327 // object shall be complete. 4328 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4329 !Var->getLinkage() && !Var->isInvalidDecl() && 4330 RequireCompleteType(Var->getLocation(), Type, 4331 diag::err_typecheck_decl_incomplete_type)) 4332 Var->setInvalidDecl(); 4333 4334 // Make sure that the type is not abstract. 4335 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4336 RequireNonAbstractType(Var->getLocation(), Type, 4337 diag::err_abstract_type_in_decl, 4338 AbstractVariableType)) 4339 Var->setInvalidDecl(); 4340 return; 4341 4342 case VarDecl::TentativeDefinition: 4343 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4344 // object that has file scope without an initializer, and without a 4345 // storage-class specifier or with the storage-class specifier "static", 4346 // constitutes a tentative definition. Note: A tentative definition with 4347 // external linkage is valid (C99 6.2.2p5). 4348 if (!Var->isInvalidDecl()) { 4349 if (const IncompleteArrayType *ArrayT 4350 = Context.getAsIncompleteArrayType(Type)) { 4351 if (RequireCompleteType(Var->getLocation(), 4352 ArrayT->getElementType(), 4353 diag::err_illegal_decl_array_incomplete_type)) 4354 Var->setInvalidDecl(); 4355 } else if (Var->getStorageClass() == VarDecl::Static) { 4356 // C99 6.9.2p3: If the declaration of an identifier for an object is 4357 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4358 // declared type shall not be an incomplete type. 4359 // NOTE: code such as the following 4360 // static struct s; 4361 // struct s { int a; }; 4362 // is accepted by gcc. Hence here we issue a warning instead of 4363 // an error and we do not invalidate the static declaration. 4364 // NOTE: to avoid multiple warnings, only check the first declaration. 4365 if (Var->getPreviousDeclaration() == 0) 4366 RequireCompleteType(Var->getLocation(), Type, 4367 diag::ext_typecheck_decl_incomplete_type); 4368 } 4369 } 4370 4371 // Record the tentative definition; we're done. 4372 if (!Var->isInvalidDecl()) 4373 TentativeDefinitions.push_back(Var); 4374 return; 4375 } 4376 4377 // Provide a specific diagnostic for uninitialized variable 4378 // definitions with incomplete array type. 4379 if (Type->isIncompleteArrayType()) { 4380 Diag(Var->getLocation(), 4381 diag::err_typecheck_incomplete_array_needs_initializer); 4382 Var->setInvalidDecl(); 4383 return; 4384 } 4385 4386 // Provide a specific diagnostic for uninitialized variable 4387 // definitions with reference type. 4388 if (Type->isReferenceType()) { 4389 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4390 << Var->getDeclName() 4391 << SourceRange(Var->getLocation(), Var->getLocation()); 4392 Var->setInvalidDecl(); 4393 return; 4394 } 4395 4396 // Do not attempt to type-check the default initializer for a 4397 // variable with dependent type. 4398 if (Type->isDependentType()) 4399 return; 4400 4401 if (Var->isInvalidDecl()) 4402 return; 4403 4404 if (RequireCompleteType(Var->getLocation(), 4405 Context.getBaseElementType(Type), 4406 diag::err_typecheck_decl_incomplete_type)) { 4407 Var->setInvalidDecl(); 4408 return; 4409 } 4410 4411 // The variable can not have an abstract class type. 4412 if (RequireNonAbstractType(Var->getLocation(), Type, 4413 diag::err_abstract_type_in_decl, 4414 AbstractVariableType)) { 4415 Var->setInvalidDecl(); 4416 return; 4417 } 4418 4419 const RecordType *Record 4420 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4421 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4422 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4423 // C++03 [dcl.init]p9: 4424 // If no initializer is specified for an object, and the 4425 // object is of (possibly cv-qualified) non-POD class type (or 4426 // array thereof), the object shall be default-initialized; if 4427 // the object is of const-qualified type, the underlying class 4428 // type shall have a user-declared default 4429 // constructor. Otherwise, if no initializer is specified for 4430 // a non- static object, the object and its subobjects, if 4431 // any, have an indeterminate initial value); if the object 4432 // or any of its subobjects are of const-qualified type, the 4433 // program is ill-formed. 4434 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4435 } else { 4436 // Check for jumps past the implicit initializer. C++0x 4437 // clarifies that this applies to a "variable with automatic 4438 // storage duration", not a "local variable". 4439 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4440 setFunctionHasBranchProtectedScope(); 4441 4442 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4443 InitializationKind Kind 4444 = InitializationKind::CreateDefault(Var->getLocation()); 4445 4446 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4447 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4448 MultiExprArg(*this, 0, 0)); 4449 if (Init.isInvalid()) 4450 Var->setInvalidDecl(); 4451 else if (Init.get()) { 4452 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4453 4454 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4455 Var->hasGlobalStorage() && 4456 !Var->getDeclContext()->isDependentContext() && 4457 !Var->getInit()->isConstantInitializer(Context, false)) 4458 Diag(Var->getLocation(), diag::warn_global_constructor); 4459 } 4460 } 4461 4462 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4463 FinalizeVarWithDestructor(Var, Record); 4464 } 4465} 4466 4467Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4468 Decl **Group, 4469 unsigned NumDecls) { 4470 llvm::SmallVector<Decl*, 8> Decls; 4471 4472 if (DS.isTypeSpecOwned()) 4473 Decls.push_back((Decl*)DS.getTypeRep()); 4474 4475 for (unsigned i = 0; i != NumDecls; ++i) 4476 if (Decl *D = Group[i]) 4477 Decls.push_back(D); 4478 4479 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4480 Decls.data(), Decls.size())); 4481} 4482 4483 4484/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4485/// to introduce parameters into function prototype scope. 4486Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4487 const DeclSpec &DS = D.getDeclSpec(); 4488 4489 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4490 VarDecl::StorageClass StorageClass = VarDecl::None; 4491 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4492 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4493 StorageClass = VarDecl::Register; 4494 StorageClassAsWritten = VarDecl::Register; 4495 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4496 Diag(DS.getStorageClassSpecLoc(), 4497 diag::err_invalid_storage_class_in_func_decl); 4498 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4499 } 4500 4501 if (D.getDeclSpec().isThreadSpecified()) 4502 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4503 4504 DiagnoseFunctionSpecifiers(D); 4505 4506 // Check that there are no default arguments inside the type of this 4507 // parameter (C++ only). 4508 if (getLangOptions().CPlusPlus) 4509 CheckExtraCXXDefaultArguments(D); 4510 4511 TagDecl *OwnedDecl = 0; 4512 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4513 QualType parmDeclType = TInfo->getType(); 4514 4515 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4516 // C++ [dcl.fct]p6: 4517 // Types shall not be defined in return or parameter types. 4518 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4519 << Context.getTypeDeclType(OwnedDecl); 4520 } 4521 4522 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4523 IdentifierInfo *II = D.getIdentifier(); 4524 if (II) { 4525 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4526 ForRedeclaration); 4527 LookupName(R, S); 4528 if (R.isSingleResult()) { 4529 NamedDecl *PrevDecl = R.getFoundDecl(); 4530 if (PrevDecl->isTemplateParameter()) { 4531 // Maybe we will complain about the shadowed template parameter. 4532 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4533 // Just pretend that we didn't see the previous declaration. 4534 PrevDecl = 0; 4535 } else if (S->isDeclScope(PrevDecl)) { 4536 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4537 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4538 4539 // Recover by removing the name 4540 II = 0; 4541 D.SetIdentifier(0, D.getIdentifierLoc()); 4542 D.setInvalidType(true); 4543 } 4544 } 4545 } 4546 4547 // Temporarily put parameter variables in the translation unit, not 4548 // the enclosing context. This prevents them from accidentally 4549 // looking like class members in C++. 4550 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4551 TInfo, parmDeclType, II, 4552 D.getIdentifierLoc(), 4553 StorageClass, StorageClassAsWritten); 4554 4555 if (D.isInvalidType()) 4556 New->setInvalidDecl(); 4557 4558 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4559 if (D.getCXXScopeSpec().isSet()) { 4560 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4561 << D.getCXXScopeSpec().getRange(); 4562 New->setInvalidDecl(); 4563 } 4564 4565 // Add the parameter declaration into this scope. 4566 S->AddDecl(New); 4567 if (II) 4568 IdResolver.AddDecl(New); 4569 4570 ProcessDeclAttributes(S, New, D); 4571 4572 if (New->hasAttr<BlocksAttr>()) { 4573 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4574 } 4575 return New; 4576} 4577 4578/// \brief Synthesizes a variable for a parameter arising from a 4579/// typedef. 4580ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4581 SourceLocation Loc, 4582 QualType T) { 4583 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4584 T, Context.getTrivialTypeSourceInfo(T, Loc), 4585 VarDecl::None, VarDecl::None, 0); 4586 Param->setImplicit(); 4587 return Param; 4588} 4589 4590ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4591 TypeSourceInfo *TSInfo, QualType T, 4592 IdentifierInfo *Name, 4593 SourceLocation NameLoc, 4594 VarDecl::StorageClass StorageClass, 4595 VarDecl::StorageClass StorageClassAsWritten) { 4596 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4597 adjustParameterType(T), TSInfo, 4598 StorageClass, StorageClassAsWritten, 4599 0); 4600 4601 // Parameters can not be abstract class types. 4602 // For record types, this is done by the AbstractClassUsageDiagnoser once 4603 // the class has been completely parsed. 4604 if (!CurContext->isRecord() && 4605 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4606 AbstractParamType)) 4607 New->setInvalidDecl(); 4608 4609 // Parameter declarators cannot be interface types. All ObjC objects are 4610 // passed by reference. 4611 if (T->isObjCObjectType()) { 4612 Diag(NameLoc, 4613 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4614 New->setInvalidDecl(); 4615 } 4616 4617 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4618 // duration shall not be qualified by an address-space qualifier." 4619 // Since all parameters have automatic store duration, they can not have 4620 // an address space. 4621 if (T.getAddressSpace() != 0) { 4622 Diag(NameLoc, diag::err_arg_with_address_space); 4623 New->setInvalidDecl(); 4624 } 4625 4626 return New; 4627} 4628 4629void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4630 SourceLocation LocAfterDecls) { 4631 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4632 "Not a function declarator!"); 4633 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4634 4635 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4636 // for a K&R function. 4637 if (!FTI.hasPrototype) { 4638 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4639 --i; 4640 if (FTI.ArgInfo[i].Param == 0) { 4641 llvm::SmallString<256> Code; 4642 llvm::raw_svector_ostream(Code) << " int " 4643 << FTI.ArgInfo[i].Ident->getName() 4644 << ";\n"; 4645 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4646 << FTI.ArgInfo[i].Ident 4647 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4648 4649 // Implicitly declare the argument as type 'int' for lack of a better 4650 // type. 4651 DeclSpec DS; 4652 const char* PrevSpec; // unused 4653 unsigned DiagID; // unused 4654 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4655 PrevSpec, DiagID); 4656 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4657 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4658 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4659 } 4660 } 4661 } 4662} 4663 4664Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4665 Declarator &D) { 4666 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4667 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4668 "Not a function declarator!"); 4669 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4670 4671 if (FTI.hasPrototype) { 4672 // FIXME: Diagnose arguments without names in C. 4673 } 4674 4675 Scope *ParentScope = FnBodyScope->getParent(); 4676 4677 Decl *DP = HandleDeclarator(ParentScope, D, 4678 MultiTemplateParamsArg(*this), 4679 /*IsFunctionDefinition=*/true); 4680 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4681} 4682 4683static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4684 // Don't warn about invalid declarations. 4685 if (FD->isInvalidDecl()) 4686 return false; 4687 4688 // Or declarations that aren't global. 4689 if (!FD->isGlobal()) 4690 return false; 4691 4692 // Don't warn about C++ member functions. 4693 if (isa<CXXMethodDecl>(FD)) 4694 return false; 4695 4696 // Don't warn about 'main'. 4697 if (FD->isMain()) 4698 return false; 4699 4700 // Don't warn about inline functions. 4701 if (FD->isInlineSpecified()) 4702 return false; 4703 4704 // Don't warn about function templates. 4705 if (FD->getDescribedFunctionTemplate()) 4706 return false; 4707 4708 // Don't warn about function template specializations. 4709 if (FD->isFunctionTemplateSpecialization()) 4710 return false; 4711 4712 bool MissingPrototype = true; 4713 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4714 Prev; Prev = Prev->getPreviousDeclaration()) { 4715 // Ignore any declarations that occur in function or method 4716 // scope, because they aren't visible from the header. 4717 if (Prev->getDeclContext()->isFunctionOrMethod()) 4718 continue; 4719 4720 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4721 break; 4722 } 4723 4724 return MissingPrototype; 4725} 4726 4727Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4728 // Clear the last template instantiation error context. 4729 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4730 4731 if (!D) 4732 return D; 4733 FunctionDecl *FD = 0; 4734 4735 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4736 FD = FunTmpl->getTemplatedDecl(); 4737 else 4738 FD = cast<FunctionDecl>(D); 4739 4740 // Enter a new function scope 4741 PushFunctionScope(); 4742 4743 // See if this is a redefinition. 4744 // But don't complain if we're in GNU89 mode and the previous definition 4745 // was an extern inline function. 4746 const FunctionDecl *Definition; 4747 if (FD->hasBody(Definition) && 4748 !canRedefineFunction(Definition, getLangOptions())) { 4749 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4750 Diag(Definition->getLocation(), diag::note_previous_definition); 4751 } 4752 4753 // Builtin functions cannot be defined. 4754 if (unsigned BuiltinID = FD->getBuiltinID()) { 4755 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4756 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4757 FD->setInvalidDecl(); 4758 } 4759 } 4760 4761 // The return type of a function definition must be complete 4762 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4763 QualType ResultType = FD->getResultType(); 4764 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4765 !FD->isInvalidDecl() && 4766 RequireCompleteType(FD->getLocation(), ResultType, 4767 diag::err_func_def_incomplete_result)) 4768 FD->setInvalidDecl(); 4769 4770 // GNU warning -Wmissing-prototypes: 4771 // Warn if a global function is defined without a previous 4772 // prototype declaration. This warning is issued even if the 4773 // definition itself provides a prototype. The aim is to detect 4774 // global functions that fail to be declared in header files. 4775 if (ShouldWarnAboutMissingPrototype(FD)) 4776 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4777 4778 if (FnBodyScope) 4779 PushDeclContext(FnBodyScope, FD); 4780 4781 // Check the validity of our function parameters 4782 CheckParmsForFunctionDef(FD); 4783 4784 bool ShouldCheckShadow = 4785 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4786 4787 // Introduce our parameters into the function scope 4788 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4789 ParmVarDecl *Param = FD->getParamDecl(p); 4790 Param->setOwningFunction(FD); 4791 4792 // If this has an identifier, add it to the scope stack. 4793 if (Param->getIdentifier() && FnBodyScope) { 4794 if (ShouldCheckShadow) 4795 CheckShadow(FnBodyScope, Param); 4796 4797 PushOnScopeChains(Param, FnBodyScope); 4798 } 4799 } 4800 4801 // Checking attributes of current function definition 4802 // dllimport attribute. 4803 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 4804 if (DA && (!FD->getAttr<DLLExportAttr>())) { 4805 // dllimport attribute cannot be directly applied to definition. 4806 if (!DA->isInherited()) { 4807 Diag(FD->getLocation(), 4808 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4809 << "dllimport"; 4810 FD->setInvalidDecl(); 4811 return FD; 4812 } 4813 4814 // Visual C++ appears to not think this is an issue, so only issue 4815 // a warning when Microsoft extensions are disabled. 4816 if (!LangOpts.Microsoft) { 4817 // If a symbol previously declared dllimport is later defined, the 4818 // attribute is ignored in subsequent references, and a warning is 4819 // emitted. 4820 Diag(FD->getLocation(), 4821 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4822 << FD->getName() << "dllimport"; 4823 } 4824 } 4825 return FD; 4826} 4827 4828/// \brief Given the set of return statements within a function body, 4829/// compute the variables that are subject to the named return value 4830/// optimization. 4831/// 4832/// Each of the variables that is subject to the named return value 4833/// optimization will be marked as NRVO variables in the AST, and any 4834/// return statement that has a marked NRVO variable as its NRVO candidate can 4835/// use the named return value optimization. 4836/// 4837/// This function applies a very simplistic algorithm for NRVO: if every return 4838/// statement in the function has the same NRVO candidate, that candidate is 4839/// the NRVO variable. 4840/// 4841/// FIXME: Employ a smarter algorithm that accounts for multiple return 4842/// statements and the lifetimes of the NRVO candidates. We should be able to 4843/// find a maximal set of NRVO variables. 4844static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4845 const VarDecl *NRVOCandidate = 0; 4846 for (unsigned I = 0; I != NumReturns; ++I) { 4847 if (!Returns[I]->getNRVOCandidate()) 4848 return; 4849 4850 if (!NRVOCandidate) 4851 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4852 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4853 return; 4854 } 4855 4856 if (NRVOCandidate) 4857 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4858} 4859 4860Decl *Sema::ActOnFinishFunctionBody(Decl *D, StmtArg BodyArg) { 4861 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4862} 4863 4864Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, StmtArg BodyArg, 4865 bool IsInstantiation) { 4866 Stmt *Body = BodyArg.takeAs<Stmt>(); 4867 4868 FunctionDecl *FD = 0; 4869 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4870 if (FunTmpl) 4871 FD = FunTmpl->getTemplatedDecl(); 4872 else 4873 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4874 4875 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4876 4877 if (FD) { 4878 FD->setBody(Body); 4879 if (FD->isMain()) { 4880 // C and C++ allow for main to automagically return 0. 4881 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4882 FD->setHasImplicitReturnZero(true); 4883 WP.disableCheckFallThrough(); 4884 } 4885 4886 if (!FD->isInvalidDecl()) { 4887 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4888 4889 // If this is a constructor, we need a vtable. 4890 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4891 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4892 4893 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4894 FunctionScopes.back()->Returns.size()); 4895 } 4896 4897 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4898 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4899 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4900 MD->setBody(Body); 4901 MD->setEndLoc(Body->getLocEnd()); 4902 if (!MD->isInvalidDecl()) 4903 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4904 } else { 4905 return 0; 4906 } 4907 4908 // Verify and clean out per-function state. 4909 4910 // Check goto/label use. 4911 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4912 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4913 LabelStmt *L = I->second; 4914 4915 // Verify that we have no forward references left. If so, there was a goto 4916 // or address of a label taken, but no definition of it. Label fwd 4917 // definitions are indicated with a null substmt. 4918 if (L->getSubStmt() != 0) 4919 continue; 4920 4921 // Emit error. 4922 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4923 4924 // At this point, we have gotos that use the bogus label. Stitch it into 4925 // the function body so that they aren't leaked and that the AST is well 4926 // formed. 4927 if (Body == 0) { 4928 // The whole function wasn't parsed correctly. 4929 continue; 4930 } 4931 4932 // Otherwise, the body is valid: we want to stitch the label decl into the 4933 // function somewhere so that it is properly owned and so that the goto 4934 // has a valid target. Do this by creating a new compound stmt with the 4935 // label in it. 4936 4937 // Give the label a sub-statement. 4938 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4939 4940 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4941 cast<CXXTryStmt>(Body)->getTryBlock() : 4942 cast<CompoundStmt>(Body); 4943 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4944 Compound->body_end()); 4945 Elements.push_back(L); 4946 Compound->setStmts(Context, Elements.data(), Elements.size()); 4947 } 4948 4949 if (Body) { 4950 // C++ constructors that have function-try-blocks can't have return 4951 // statements in the handlers of that block. (C++ [except.handle]p14) 4952 // Verify this. 4953 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4954 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4955 4956 // Verify that that gotos and switch cases don't jump into scopes illegally. 4957 // Verify that that gotos and switch cases don't jump into scopes illegally. 4958 if (FunctionNeedsScopeChecking() && 4959 !dcl->isInvalidDecl() && 4960 !hasAnyErrorsInThisFunction()) 4961 DiagnoseInvalidJumps(Body); 4962 4963 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 4964 if (!Destructor->getParent()->isDependentType()) 4965 CheckDestructor(Destructor); 4966 4967 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4968 Destructor->getParent()); 4969 } 4970 4971 // If any errors have occurred, clear out any temporaries that may have 4972 // been leftover. This ensures that these temporaries won't be picked up for 4973 // deletion in some later function. 4974 if (PP.getDiagnostics().hasErrorOccurred()) 4975 ExprTemporaries.clear(); 4976 else if (!isa<FunctionTemplateDecl>(dcl)) { 4977 // Since the body is valid, issue any analysis-based warnings that are 4978 // enabled. 4979 QualType ResultType; 4980 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4981 ResultType = FD->getResultType(); 4982 } 4983 else { 4984 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4985 ResultType = MD->getResultType(); 4986 } 4987 AnalysisWarnings.IssueWarnings(WP, dcl); 4988 } 4989 4990 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4991 } 4992 4993 if (!IsInstantiation) 4994 PopDeclContext(); 4995 4996 PopFunctionOrBlockScope(); 4997 4998 // If any errors have occurred, clear out any temporaries that may have 4999 // been leftover. This ensures that these temporaries won't be picked up for 5000 // deletion in some later function. 5001 if (getDiagnostics().hasErrorOccurred()) 5002 ExprTemporaries.clear(); 5003 5004 return dcl; 5005} 5006 5007/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5008/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5009NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5010 IdentifierInfo &II, Scope *S) { 5011 // Before we produce a declaration for an implicitly defined 5012 // function, see whether there was a locally-scoped declaration of 5013 // this name as a function or variable. If so, use that 5014 // (non-visible) declaration, and complain about it. 5015 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5016 = LocallyScopedExternalDecls.find(&II); 5017 if (Pos != LocallyScopedExternalDecls.end()) { 5018 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5019 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5020 return Pos->second; 5021 } 5022 5023 // Extension in C99. Legal in C90, but warn about it. 5024 if (II.getName().startswith("__builtin_")) 5025 Diag(Loc, diag::warn_builtin_unknown) << &II; 5026 else if (getLangOptions().C99) 5027 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5028 else 5029 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5030 5031 // Set a Declarator for the implicit definition: int foo(); 5032 const char *Dummy; 5033 DeclSpec DS; 5034 unsigned DiagID; 5035 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5036 Error = Error; // Silence warning. 5037 assert(!Error && "Error setting up implicit decl!"); 5038 Declarator D(DS, Declarator::BlockContext); 5039 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5040 0, 0, false, SourceLocation(), 5041 false, 0,0,0, Loc, Loc, D), 5042 SourceLocation()); 5043 D.SetIdentifier(&II, Loc); 5044 5045 // Insert this function into translation-unit scope. 5046 5047 DeclContext *PrevDC = CurContext; 5048 CurContext = Context.getTranslationUnitDecl(); 5049 5050 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5051 FD->setImplicit(); 5052 5053 CurContext = PrevDC; 5054 5055 AddKnownFunctionAttributes(FD); 5056 5057 return FD; 5058} 5059 5060/// \brief Adds any function attributes that we know a priori based on 5061/// the declaration of this function. 5062/// 5063/// These attributes can apply both to implicitly-declared builtins 5064/// (like __builtin___printf_chk) or to library-declared functions 5065/// like NSLog or printf. 5066void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5067 if (FD->isInvalidDecl()) 5068 return; 5069 5070 // If this is a built-in function, map its builtin attributes to 5071 // actual attributes. 5072 if (unsigned BuiltinID = FD->getBuiltinID()) { 5073 // Handle printf-formatting attributes. 5074 unsigned FormatIdx; 5075 bool HasVAListArg; 5076 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5077 if (!FD->getAttr<FormatAttr>()) 5078 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5079 "printf", FormatIdx+1, 5080 HasVAListArg ? 0 : FormatIdx+2)); 5081 } 5082 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5083 HasVAListArg)) { 5084 if (!FD->getAttr<FormatAttr>()) 5085 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5086 "scanf", FormatIdx+1, 5087 HasVAListArg ? 0 : FormatIdx+2)); 5088 } 5089 5090 // Mark const if we don't care about errno and that is the only 5091 // thing preventing the function from being const. This allows 5092 // IRgen to use LLVM intrinsics for such functions. 5093 if (!getLangOptions().MathErrno && 5094 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5095 if (!FD->getAttr<ConstAttr>()) 5096 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5097 } 5098 5099 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5100 FD->setType(Context.getNoReturnType(FD->getType())); 5101 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5102 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5103 if (Context.BuiltinInfo.isConst(BuiltinID)) 5104 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5105 } 5106 5107 IdentifierInfo *Name = FD->getIdentifier(); 5108 if (!Name) 5109 return; 5110 if ((!getLangOptions().CPlusPlus && 5111 FD->getDeclContext()->isTranslationUnit()) || 5112 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5113 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5114 LinkageSpecDecl::lang_c)) { 5115 // Okay: this could be a libc/libm/Objective-C function we know 5116 // about. 5117 } else 5118 return; 5119 5120 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5121 // FIXME: NSLog and NSLogv should be target specific 5122 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5123 // FIXME: We known better than our headers. 5124 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5125 } else 5126 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5127 "printf", 1, 5128 Name->isStr("NSLogv") ? 0 : 2)); 5129 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5130 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5131 // target-specific builtins, perhaps? 5132 if (!FD->getAttr<FormatAttr>()) 5133 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5134 "printf", 2, 5135 Name->isStr("vasprintf") ? 0 : 3)); 5136 } 5137} 5138 5139TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5140 TypeSourceInfo *TInfo) { 5141 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5142 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5143 5144 if (!TInfo) { 5145 assert(D.isInvalidType() && "no declarator info for valid type"); 5146 TInfo = Context.getTrivialTypeSourceInfo(T); 5147 } 5148 5149 // Scope manipulation handled by caller. 5150 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5151 D.getIdentifierLoc(), 5152 D.getIdentifier(), 5153 TInfo); 5154 5155 if (const TagType *TT = T->getAs<TagType>()) { 5156 TagDecl *TD = TT->getDecl(); 5157 5158 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5159 // keep track of the TypedefDecl. 5160 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5161 TD->setTypedefForAnonDecl(NewTD); 5162 } 5163 5164 if (D.isInvalidType()) 5165 NewTD->setInvalidDecl(); 5166 return NewTD; 5167} 5168 5169 5170/// \brief Determine whether a tag with a given kind is acceptable 5171/// as a redeclaration of the given tag declaration. 5172/// 5173/// \returns true if the new tag kind is acceptable, false otherwise. 5174bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5175 TagTypeKind NewTag, 5176 SourceLocation NewTagLoc, 5177 const IdentifierInfo &Name) { 5178 // C++ [dcl.type.elab]p3: 5179 // The class-key or enum keyword present in the 5180 // elaborated-type-specifier shall agree in kind with the 5181 // declaration to which the name in the elaborated-type-specifier 5182 // refers. This rule also applies to the form of 5183 // elaborated-type-specifier that declares a class-name or 5184 // friend class since it can be construed as referring to the 5185 // definition of the class. Thus, in any 5186 // elaborated-type-specifier, the enum keyword shall be used to 5187 // refer to an enumeration (7.2), the union class-key shall be 5188 // used to refer to a union (clause 9), and either the class or 5189 // struct class-key shall be used to refer to a class (clause 9) 5190 // declared using the class or struct class-key. 5191 TagTypeKind OldTag = Previous->getTagKind(); 5192 if (OldTag == NewTag) 5193 return true; 5194 5195 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5196 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5197 // Warn about the struct/class tag mismatch. 5198 bool isTemplate = false; 5199 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5200 isTemplate = Record->getDescribedClassTemplate(); 5201 5202 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5203 << (NewTag == TTK_Class) 5204 << isTemplate << &Name 5205 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5206 OldTag == TTK_Class? "class" : "struct"); 5207 Diag(Previous->getLocation(), diag::note_previous_use); 5208 return true; 5209 } 5210 return false; 5211} 5212 5213/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5214/// former case, Name will be non-null. In the later case, Name will be null. 5215/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5216/// reference/declaration/definition of a tag. 5217Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5218 SourceLocation KWLoc, CXXScopeSpec &SS, 5219 IdentifierInfo *Name, SourceLocation NameLoc, 5220 AttributeList *Attr, AccessSpecifier AS, 5221 MultiTemplateParamsArg TemplateParameterLists, 5222 bool &OwnedDecl, bool &IsDependent) { 5223 // If this is not a definition, it must have a name. 5224 assert((Name != 0 || TUK == TUK_Definition) && 5225 "Nameless record must be a definition!"); 5226 5227 OwnedDecl = false; 5228 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5229 5230 // FIXME: Check explicit specializations more carefully. 5231 bool isExplicitSpecialization = false; 5232 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5233 bool Invalid = false; 5234 if (TUK != TUK_Reference) { 5235 if (TemplateParameterList *TemplateParams 5236 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5237 (TemplateParameterList**)TemplateParameterLists.get(), 5238 TemplateParameterLists.size(), 5239 TUK == TUK_Friend, 5240 isExplicitSpecialization, 5241 Invalid)) { 5242 // All but one template parameter lists have been matching. 5243 --NumMatchedTemplateParamLists; 5244 5245 if (TemplateParams->size() > 0) { 5246 // This is a declaration or definition of a class template (which may 5247 // be a member of another template). 5248 if (Invalid) 5249 return 0; 5250 5251 OwnedDecl = false; 5252 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5253 SS, Name, NameLoc, Attr, 5254 TemplateParams, 5255 AS); 5256 TemplateParameterLists.release(); 5257 return Result.get(); 5258 } else { 5259 // The "template<>" header is extraneous. 5260 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5261 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5262 isExplicitSpecialization = true; 5263 } 5264 } 5265 } 5266 5267 DeclContext *SearchDC = CurContext; 5268 DeclContext *DC = CurContext; 5269 bool isStdBadAlloc = false; 5270 5271 RedeclarationKind Redecl = ForRedeclaration; 5272 if (TUK == TUK_Friend || TUK == TUK_Reference) 5273 Redecl = NotForRedeclaration; 5274 5275 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5276 5277 if (Name && SS.isNotEmpty()) { 5278 // We have a nested-name tag ('struct foo::bar'). 5279 5280 // Check for invalid 'foo::'. 5281 if (SS.isInvalid()) { 5282 Name = 0; 5283 goto CreateNewDecl; 5284 } 5285 5286 // If this is a friend or a reference to a class in a dependent 5287 // context, don't try to make a decl for it. 5288 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5289 DC = computeDeclContext(SS, false); 5290 if (!DC) { 5291 IsDependent = true; 5292 return 0; 5293 } 5294 } else { 5295 DC = computeDeclContext(SS, true); 5296 if (!DC) { 5297 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5298 << SS.getRange(); 5299 return 0; 5300 } 5301 } 5302 5303 if (RequireCompleteDeclContext(SS, DC)) 5304 return 0; 5305 5306 SearchDC = DC; 5307 // Look-up name inside 'foo::'. 5308 LookupQualifiedName(Previous, DC); 5309 5310 if (Previous.isAmbiguous()) 5311 return 0; 5312 5313 if (Previous.empty()) { 5314 // Name lookup did not find anything. However, if the 5315 // nested-name-specifier refers to the current instantiation, 5316 // and that current instantiation has any dependent base 5317 // classes, we might find something at instantiation time: treat 5318 // this as a dependent elaborated-type-specifier. 5319 if (Previous.wasNotFoundInCurrentInstantiation()) { 5320 IsDependent = true; 5321 return 0; 5322 } 5323 5324 // A tag 'foo::bar' must already exist. 5325 Diag(NameLoc, diag::err_not_tag_in_scope) 5326 << Kind << Name << DC << SS.getRange(); 5327 Name = 0; 5328 Invalid = true; 5329 goto CreateNewDecl; 5330 } 5331 } else if (Name) { 5332 // If this is a named struct, check to see if there was a previous forward 5333 // declaration or definition. 5334 // FIXME: We're looking into outer scopes here, even when we 5335 // shouldn't be. Doing so can result in ambiguities that we 5336 // shouldn't be diagnosing. 5337 LookupName(Previous, S); 5338 5339 // Note: there used to be some attempt at recovery here. 5340 if (Previous.isAmbiguous()) 5341 return 0; 5342 5343 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5344 // FIXME: This makes sure that we ignore the contexts associated 5345 // with C structs, unions, and enums when looking for a matching 5346 // tag declaration or definition. See the similar lookup tweak 5347 // in Sema::LookupName; is there a better way to deal with this? 5348 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5349 SearchDC = SearchDC->getParent(); 5350 } 5351 } 5352 5353 if (Previous.isSingleResult() && 5354 Previous.getFoundDecl()->isTemplateParameter()) { 5355 // Maybe we will complain about the shadowed template parameter. 5356 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5357 // Just pretend that we didn't see the previous declaration. 5358 Previous.clear(); 5359 } 5360 5361 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5362 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5363 // This is a declaration of or a reference to "std::bad_alloc". 5364 isStdBadAlloc = true; 5365 5366 if (Previous.empty() && StdBadAlloc) { 5367 // std::bad_alloc has been implicitly declared (but made invisible to 5368 // name lookup). Fill in this implicit declaration as the previous 5369 // declaration, so that the declarations get chained appropriately. 5370 Previous.addDecl(getStdBadAlloc()); 5371 } 5372 } 5373 5374 // If we didn't find a previous declaration, and this is a reference 5375 // (or friend reference), move to the correct scope. In C++, we 5376 // also need to do a redeclaration lookup there, just in case 5377 // there's a shadow friend decl. 5378 if (Name && Previous.empty() && 5379 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5380 if (Invalid) goto CreateNewDecl; 5381 assert(SS.isEmpty()); 5382 5383 if (TUK == TUK_Reference) { 5384 // C++ [basic.scope.pdecl]p5: 5385 // -- for an elaborated-type-specifier of the form 5386 // 5387 // class-key identifier 5388 // 5389 // if the elaborated-type-specifier is used in the 5390 // decl-specifier-seq or parameter-declaration-clause of a 5391 // function defined in namespace scope, the identifier is 5392 // declared as a class-name in the namespace that contains 5393 // the declaration; otherwise, except as a friend 5394 // declaration, the identifier is declared in the smallest 5395 // non-class, non-function-prototype scope that contains the 5396 // declaration. 5397 // 5398 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5399 // C structs and unions. 5400 // 5401 // It is an error in C++ to declare (rather than define) an enum 5402 // type, including via an elaborated type specifier. We'll 5403 // diagnose that later; for now, declare the enum in the same 5404 // scope as we would have picked for any other tag type. 5405 // 5406 // GNU C also supports this behavior as part of its incomplete 5407 // enum types extension, while GNU C++ does not. 5408 // 5409 // Find the context where we'll be declaring the tag. 5410 // FIXME: We would like to maintain the current DeclContext as the 5411 // lexical context, 5412 while (SearchDC->isRecord()) 5413 SearchDC = SearchDC->getParent(); 5414 5415 // Find the scope where we'll be declaring the tag. 5416 while (S->isClassScope() || 5417 (getLangOptions().CPlusPlus && 5418 S->isFunctionPrototypeScope()) || 5419 ((S->getFlags() & Scope::DeclScope) == 0) || 5420 (S->getEntity() && 5421 ((DeclContext *)S->getEntity())->isTransparentContext())) 5422 S = S->getParent(); 5423 } else { 5424 assert(TUK == TUK_Friend); 5425 // C++ [namespace.memdef]p3: 5426 // If a friend declaration in a non-local class first declares a 5427 // class or function, the friend class or function is a member of 5428 // the innermost enclosing namespace. 5429 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5430 } 5431 5432 // In C++, we need to do a redeclaration lookup to properly 5433 // diagnose some problems. 5434 if (getLangOptions().CPlusPlus) { 5435 Previous.setRedeclarationKind(ForRedeclaration); 5436 LookupQualifiedName(Previous, SearchDC); 5437 } 5438 } 5439 5440 if (!Previous.empty()) { 5441 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5442 5443 // It's okay to have a tag decl in the same scope as a typedef 5444 // which hides a tag decl in the same scope. Finding this 5445 // insanity with a redeclaration lookup can only actually happen 5446 // in C++. 5447 // 5448 // This is also okay for elaborated-type-specifiers, which is 5449 // technically forbidden by the current standard but which is 5450 // okay according to the likely resolution of an open issue; 5451 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5452 if (getLangOptions().CPlusPlus) { 5453 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5454 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5455 TagDecl *Tag = TT->getDecl(); 5456 if (Tag->getDeclName() == Name && 5457 Tag->getDeclContext()->getLookupContext() 5458 ->Equals(TD->getDeclContext()->getLookupContext())) { 5459 PrevDecl = Tag; 5460 Previous.clear(); 5461 Previous.addDecl(Tag); 5462 } 5463 } 5464 } 5465 } 5466 5467 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5468 // If this is a use of a previous tag, or if the tag is already declared 5469 // in the same scope (so that the definition/declaration completes or 5470 // rementions the tag), reuse the decl. 5471 if (TUK == TUK_Reference || TUK == TUK_Friend || 5472 isDeclInScope(PrevDecl, SearchDC, S)) { 5473 // Make sure that this wasn't declared as an enum and now used as a 5474 // struct or something similar. 5475 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5476 bool SafeToContinue 5477 = (PrevTagDecl->getTagKind() != TTK_Enum && 5478 Kind != TTK_Enum); 5479 if (SafeToContinue) 5480 Diag(KWLoc, diag::err_use_with_wrong_tag) 5481 << Name 5482 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5483 PrevTagDecl->getKindName()); 5484 else 5485 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5486 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5487 5488 if (SafeToContinue) 5489 Kind = PrevTagDecl->getTagKind(); 5490 else { 5491 // Recover by making this an anonymous redefinition. 5492 Name = 0; 5493 Previous.clear(); 5494 Invalid = true; 5495 } 5496 } 5497 5498 if (!Invalid) { 5499 // If this is a use, just return the declaration we found. 5500 5501 // FIXME: In the future, return a variant or some other clue 5502 // for the consumer of this Decl to know it doesn't own it. 5503 // For our current ASTs this shouldn't be a problem, but will 5504 // need to be changed with DeclGroups. 5505 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5506 TUK == TUK_Friend) 5507 return PrevTagDecl; 5508 5509 // Diagnose attempts to redefine a tag. 5510 if (TUK == TUK_Definition) { 5511 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5512 // If we're defining a specialization and the previous definition 5513 // is from an implicit instantiation, don't emit an error 5514 // here; we'll catch this in the general case below. 5515 if (!isExplicitSpecialization || 5516 !isa<CXXRecordDecl>(Def) || 5517 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5518 == TSK_ExplicitSpecialization) { 5519 Diag(NameLoc, diag::err_redefinition) << Name; 5520 Diag(Def->getLocation(), diag::note_previous_definition); 5521 // If this is a redefinition, recover by making this 5522 // struct be anonymous, which will make any later 5523 // references get the previous definition. 5524 Name = 0; 5525 Previous.clear(); 5526 Invalid = true; 5527 } 5528 } else { 5529 // If the type is currently being defined, complain 5530 // about a nested redefinition. 5531 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5532 if (Tag->isBeingDefined()) { 5533 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5534 Diag(PrevTagDecl->getLocation(), 5535 diag::note_previous_definition); 5536 Name = 0; 5537 Previous.clear(); 5538 Invalid = true; 5539 } 5540 } 5541 5542 // Okay, this is definition of a previously declared or referenced 5543 // tag PrevDecl. We're going to create a new Decl for it. 5544 } 5545 } 5546 // If we get here we have (another) forward declaration or we 5547 // have a definition. Just create a new decl. 5548 5549 } else { 5550 // If we get here, this is a definition of a new tag type in a nested 5551 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5552 // new decl/type. We set PrevDecl to NULL so that the entities 5553 // have distinct types. 5554 Previous.clear(); 5555 } 5556 // If we get here, we're going to create a new Decl. If PrevDecl 5557 // is non-NULL, it's a definition of the tag declared by 5558 // PrevDecl. If it's NULL, we have a new definition. 5559 5560 5561 // Otherwise, PrevDecl is not a tag, but was found with tag 5562 // lookup. This is only actually possible in C++, where a few 5563 // things like templates still live in the tag namespace. 5564 } else { 5565 assert(getLangOptions().CPlusPlus); 5566 5567 // Use a better diagnostic if an elaborated-type-specifier 5568 // found the wrong kind of type on the first 5569 // (non-redeclaration) lookup. 5570 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5571 !Previous.isForRedeclaration()) { 5572 unsigned Kind = 0; 5573 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5574 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5575 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5576 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5577 Invalid = true; 5578 5579 // Otherwise, only diagnose if the declaration is in scope. 5580 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5581 // do nothing 5582 5583 // Diagnose implicit declarations introduced by elaborated types. 5584 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5585 unsigned Kind = 0; 5586 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5587 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5588 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5589 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5590 Invalid = true; 5591 5592 // Otherwise it's a declaration. Call out a particularly common 5593 // case here. 5594 } else if (isa<TypedefDecl>(PrevDecl)) { 5595 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5596 << Name 5597 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5598 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5599 Invalid = true; 5600 5601 // Otherwise, diagnose. 5602 } else { 5603 // The tag name clashes with something else in the target scope, 5604 // issue an error and recover by making this tag be anonymous. 5605 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5606 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5607 Name = 0; 5608 Invalid = true; 5609 } 5610 5611 // The existing declaration isn't relevant to us; we're in a 5612 // new scope, so clear out the previous declaration. 5613 Previous.clear(); 5614 } 5615 } 5616 5617CreateNewDecl: 5618 5619 TagDecl *PrevDecl = 0; 5620 if (Previous.isSingleResult()) 5621 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5622 5623 // If there is an identifier, use the location of the identifier as the 5624 // location of the decl, otherwise use the location of the struct/union 5625 // keyword. 5626 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5627 5628 // Otherwise, create a new declaration. If there is a previous 5629 // declaration of the same entity, the two will be linked via 5630 // PrevDecl. 5631 TagDecl *New; 5632 5633 if (Kind == TTK_Enum) { 5634 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5635 // enum X { A, B, C } D; D should chain to X. 5636 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5637 cast_or_null<EnumDecl>(PrevDecl)); 5638 // If this is an undefined enum, warn. 5639 if (TUK != TUK_Definition && !Invalid) { 5640 TagDecl *Def; 5641 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5642 Diag(Loc, diag::ext_forward_ref_enum_def) 5643 << New; 5644 Diag(Def->getLocation(), diag::note_previous_definition); 5645 } else { 5646 Diag(Loc, 5647 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5648 : diag::ext_forward_ref_enum); 5649 } 5650 } 5651 } else { 5652 // struct/union/class 5653 5654 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5655 // struct X { int A; } D; D should chain to X. 5656 if (getLangOptions().CPlusPlus) { 5657 // FIXME: Look for a way to use RecordDecl for simple structs. 5658 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5659 cast_or_null<CXXRecordDecl>(PrevDecl)); 5660 5661 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5662 StdBadAlloc = cast<CXXRecordDecl>(New); 5663 } else 5664 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5665 cast_or_null<RecordDecl>(PrevDecl)); 5666 } 5667 5668 // Maybe add qualifier info. 5669 if (SS.isNotEmpty()) { 5670 if (SS.isSet()) { 5671 NestedNameSpecifier *NNS 5672 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5673 New->setQualifierInfo(NNS, SS.getRange()); 5674 if (NumMatchedTemplateParamLists > 0) { 5675 New->setTemplateParameterListsInfo(Context, 5676 NumMatchedTemplateParamLists, 5677 (TemplateParameterList**) TemplateParameterLists.release()); 5678 } 5679 } 5680 else 5681 Invalid = true; 5682 } 5683 5684 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5685 // Add alignment attributes if necessary; these attributes are checked when 5686 // the ASTContext lays out the structure. 5687 // 5688 // It is important for implementing the correct semantics that this 5689 // happen here (in act on tag decl). The #pragma pack stack is 5690 // maintained as a result of parser callbacks which can occur at 5691 // many points during the parsing of a struct declaration (because 5692 // the #pragma tokens are effectively skipped over during the 5693 // parsing of the struct). 5694 AddAlignmentAttributesForRecord(RD); 5695 } 5696 5697 // If this is a specialization of a member class (of a class template), 5698 // check the specialization. 5699 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5700 Invalid = true; 5701 5702 if (Invalid) 5703 New->setInvalidDecl(); 5704 5705 if (Attr) 5706 ProcessDeclAttributeList(S, New, Attr); 5707 5708 // If we're declaring or defining a tag in function prototype scope 5709 // in C, note that this type can only be used within the function. 5710 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5711 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5712 5713 // Set the lexical context. If the tag has a C++ scope specifier, the 5714 // lexical context will be different from the semantic context. 5715 New->setLexicalDeclContext(CurContext); 5716 5717 // Mark this as a friend decl if applicable. 5718 if (TUK == TUK_Friend) 5719 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5720 5721 // Set the access specifier. 5722 if (!Invalid && SearchDC->isRecord()) 5723 SetMemberAccessSpecifier(New, PrevDecl, AS); 5724 5725 if (TUK == TUK_Definition) 5726 New->startDefinition(); 5727 5728 // If this has an identifier, add it to the scope stack. 5729 if (TUK == TUK_Friend) { 5730 // We might be replacing an existing declaration in the lookup tables; 5731 // if so, borrow its access specifier. 5732 if (PrevDecl) 5733 New->setAccess(PrevDecl->getAccess()); 5734 5735 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5736 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5737 if (Name) // can be null along some error paths 5738 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5739 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5740 } else if (Name) { 5741 S = getNonFieldDeclScope(S); 5742 PushOnScopeChains(New, S); 5743 } else { 5744 CurContext->addDecl(New); 5745 } 5746 5747 // If this is the C FILE type, notify the AST context. 5748 if (IdentifierInfo *II = New->getIdentifier()) 5749 if (!New->isInvalidDecl() && 5750 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5751 II->isStr("FILE")) 5752 Context.setFILEDecl(New); 5753 5754 OwnedDecl = true; 5755 return New; 5756} 5757 5758void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 5759 AdjustDeclIfTemplate(TagD); 5760 TagDecl *Tag = cast<TagDecl>(TagD); 5761 5762 // Enter the tag context. 5763 PushDeclContext(S, Tag); 5764} 5765 5766void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 5767 SourceLocation LBraceLoc) { 5768 AdjustDeclIfTemplate(TagD); 5769 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 5770 5771 FieldCollector->StartClass(); 5772 5773 if (!Record->getIdentifier()) 5774 return; 5775 5776 // C++ [class]p2: 5777 // [...] The class-name is also inserted into the scope of the 5778 // class itself; this is known as the injected-class-name. For 5779 // purposes of access checking, the injected-class-name is treated 5780 // as if it were a public member name. 5781 CXXRecordDecl *InjectedClassName 5782 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5783 CurContext, Record->getLocation(), 5784 Record->getIdentifier(), 5785 Record->getTagKeywordLoc(), 5786 Record); 5787 InjectedClassName->setImplicit(); 5788 InjectedClassName->setAccess(AS_public); 5789 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5790 InjectedClassName->setDescribedClassTemplate(Template); 5791 PushOnScopeChains(InjectedClassName, S); 5792 assert(InjectedClassName->isInjectedClassName() && 5793 "Broken injected-class-name"); 5794} 5795 5796void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 5797 SourceLocation RBraceLoc) { 5798 AdjustDeclIfTemplate(TagD); 5799 TagDecl *Tag = cast<TagDecl>(TagD); 5800 Tag->setRBraceLoc(RBraceLoc); 5801 5802 if (isa<CXXRecordDecl>(Tag)) 5803 FieldCollector->FinishClass(); 5804 5805 // Exit this scope of this tag's definition. 5806 PopDeclContext(); 5807 5808 // Notify the consumer that we've defined a tag. 5809 Consumer.HandleTagDeclDefinition(Tag); 5810} 5811 5812void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 5813 AdjustDeclIfTemplate(TagD); 5814 TagDecl *Tag = cast<TagDecl>(TagD); 5815 Tag->setInvalidDecl(); 5816 5817 // We're undoing ActOnTagStartDefinition here, not 5818 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5819 // the FieldCollector. 5820 5821 PopDeclContext(); 5822} 5823 5824// Note that FieldName may be null for anonymous bitfields. 5825bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5826 QualType FieldTy, const Expr *BitWidth, 5827 bool *ZeroWidth) { 5828 // Default to true; that shouldn't confuse checks for emptiness 5829 if (ZeroWidth) 5830 *ZeroWidth = true; 5831 5832 // C99 6.7.2.1p4 - verify the field type. 5833 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5834 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5835 // Handle incomplete types with specific error. 5836 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5837 return true; 5838 if (FieldName) 5839 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5840 << FieldName << FieldTy << BitWidth->getSourceRange(); 5841 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5842 << FieldTy << BitWidth->getSourceRange(); 5843 } 5844 5845 // If the bit-width is type- or value-dependent, don't try to check 5846 // it now. 5847 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5848 return false; 5849 5850 llvm::APSInt Value; 5851 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5852 return true; 5853 5854 if (Value != 0 && ZeroWidth) 5855 *ZeroWidth = false; 5856 5857 // Zero-width bitfield is ok for anonymous field. 5858 if (Value == 0 && FieldName) 5859 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5860 5861 if (Value.isSigned() && Value.isNegative()) { 5862 if (FieldName) 5863 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5864 << FieldName << Value.toString(10); 5865 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5866 << Value.toString(10); 5867 } 5868 5869 if (!FieldTy->isDependentType()) { 5870 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5871 if (Value.getZExtValue() > TypeSize) { 5872 if (!getLangOptions().CPlusPlus) { 5873 if (FieldName) 5874 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5875 << FieldName << (unsigned)Value.getZExtValue() 5876 << (unsigned)TypeSize; 5877 5878 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5879 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5880 } 5881 5882 if (FieldName) 5883 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5884 << FieldName << (unsigned)Value.getZExtValue() 5885 << (unsigned)TypeSize; 5886 else 5887 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5888 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5889 } 5890 } 5891 5892 return false; 5893} 5894 5895/// ActOnField - Each field of a struct/union/class is passed into this in order 5896/// to create a FieldDecl object for it. 5897Decl *Sema::ActOnField(Scope *S, Decl *TagD, 5898 SourceLocation DeclStart, 5899 Declarator &D, ExprTy *BitfieldWidth) { 5900 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 5901 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5902 AS_public); 5903 return Res; 5904} 5905 5906/// HandleField - Analyze a field of a C struct or a C++ data member. 5907/// 5908FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5909 SourceLocation DeclStart, 5910 Declarator &D, Expr *BitWidth, 5911 AccessSpecifier AS) { 5912 IdentifierInfo *II = D.getIdentifier(); 5913 SourceLocation Loc = DeclStart; 5914 if (II) Loc = D.getIdentifierLoc(); 5915 5916 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5917 QualType T = TInfo->getType(); 5918 if (getLangOptions().CPlusPlus) 5919 CheckExtraCXXDefaultArguments(D); 5920 5921 DiagnoseFunctionSpecifiers(D); 5922 5923 if (D.getDeclSpec().isThreadSpecified()) 5924 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5925 5926 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5927 ForRedeclaration); 5928 5929 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5930 // Maybe we will complain about the shadowed template parameter. 5931 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5932 // Just pretend that we didn't see the previous declaration. 5933 PrevDecl = 0; 5934 } 5935 5936 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5937 PrevDecl = 0; 5938 5939 bool Mutable 5940 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5941 SourceLocation TSSL = D.getSourceRange().getBegin(); 5942 FieldDecl *NewFD 5943 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5944 AS, PrevDecl, &D); 5945 5946 if (NewFD->isInvalidDecl()) 5947 Record->setInvalidDecl(); 5948 5949 if (NewFD->isInvalidDecl() && PrevDecl) { 5950 // Don't introduce NewFD into scope; there's already something 5951 // with the same name in the same scope. 5952 } else if (II) { 5953 PushOnScopeChains(NewFD, S); 5954 } else 5955 Record->addDecl(NewFD); 5956 5957 return NewFD; 5958} 5959 5960/// \brief Build a new FieldDecl and check its well-formedness. 5961/// 5962/// This routine builds a new FieldDecl given the fields name, type, 5963/// record, etc. \p PrevDecl should refer to any previous declaration 5964/// with the same name and in the same scope as the field to be 5965/// created. 5966/// 5967/// \returns a new FieldDecl. 5968/// 5969/// \todo The Declarator argument is a hack. It will be removed once 5970FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5971 TypeSourceInfo *TInfo, 5972 RecordDecl *Record, SourceLocation Loc, 5973 bool Mutable, Expr *BitWidth, 5974 SourceLocation TSSL, 5975 AccessSpecifier AS, NamedDecl *PrevDecl, 5976 Declarator *D) { 5977 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5978 bool InvalidDecl = false; 5979 if (D) InvalidDecl = D->isInvalidType(); 5980 5981 // If we receive a broken type, recover by assuming 'int' and 5982 // marking this declaration as invalid. 5983 if (T.isNull()) { 5984 InvalidDecl = true; 5985 T = Context.IntTy; 5986 } 5987 5988 QualType EltTy = Context.getBaseElementType(T); 5989 if (!EltTy->isDependentType() && 5990 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 5991 // Fields of incomplete type force their record to be invalid. 5992 Record->setInvalidDecl(); 5993 InvalidDecl = true; 5994 } 5995 5996 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5997 // than a variably modified type. 5998 if (!InvalidDecl && T->isVariablyModifiedType()) { 5999 bool SizeIsNegative; 6000 llvm::APSInt Oversized; 6001 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6002 SizeIsNegative, 6003 Oversized); 6004 if (!FixedTy.isNull()) { 6005 Diag(Loc, diag::warn_illegal_constant_array_size); 6006 T = FixedTy; 6007 } else { 6008 if (SizeIsNegative) 6009 Diag(Loc, diag::err_typecheck_negative_array_size); 6010 else if (Oversized.getBoolValue()) 6011 Diag(Loc, diag::err_array_too_large) 6012 << Oversized.toString(10); 6013 else 6014 Diag(Loc, diag::err_typecheck_field_variable_size); 6015 InvalidDecl = true; 6016 } 6017 } 6018 6019 // Fields can not have abstract class types 6020 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6021 diag::err_abstract_type_in_decl, 6022 AbstractFieldType)) 6023 InvalidDecl = true; 6024 6025 bool ZeroWidth = false; 6026 // If this is declared as a bit-field, check the bit-field. 6027 if (!InvalidDecl && BitWidth && 6028 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6029 InvalidDecl = true; 6030 DeleteExpr(BitWidth); 6031 BitWidth = 0; 6032 ZeroWidth = false; 6033 } 6034 6035 // Check that 'mutable' is consistent with the type of the declaration. 6036 if (!InvalidDecl && Mutable) { 6037 unsigned DiagID = 0; 6038 if (T->isReferenceType()) 6039 DiagID = diag::err_mutable_reference; 6040 else if (T.isConstQualified()) 6041 DiagID = diag::err_mutable_const; 6042 6043 if (DiagID) { 6044 SourceLocation ErrLoc = Loc; 6045 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6046 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6047 Diag(ErrLoc, DiagID); 6048 Mutable = false; 6049 InvalidDecl = true; 6050 } 6051 } 6052 6053 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6054 BitWidth, Mutable); 6055 if (InvalidDecl) 6056 NewFD->setInvalidDecl(); 6057 6058 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6059 Diag(Loc, diag::err_duplicate_member) << II; 6060 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6061 NewFD->setInvalidDecl(); 6062 } 6063 6064 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6065 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 6066 6067 if (!T->isPODType()) 6068 CXXRecord->setPOD(false); 6069 if (!ZeroWidth) 6070 CXXRecord->setEmpty(false); 6071 6072 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6073 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6074 if (RDecl->getDefinition()) { 6075 if (!RDecl->hasTrivialConstructor()) 6076 CXXRecord->setHasTrivialConstructor(false); 6077 if (!RDecl->hasTrivialCopyConstructor()) 6078 CXXRecord->setHasTrivialCopyConstructor(false); 6079 if (!RDecl->hasTrivialCopyAssignment()) 6080 CXXRecord->setHasTrivialCopyAssignment(false); 6081 if (!RDecl->hasTrivialDestructor()) 6082 CXXRecord->setHasTrivialDestructor(false); 6083 6084 // C++ 9.5p1: An object of a class with a non-trivial 6085 // constructor, a non-trivial copy constructor, a non-trivial 6086 // destructor, or a non-trivial copy assignment operator 6087 // cannot be a member of a union, nor can an array of such 6088 // objects. 6089 // TODO: C++0x alters this restriction significantly. 6090 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6091 NewFD->setInvalidDecl(); 6092 } 6093 } 6094 } 6095 6096 // FIXME: We need to pass in the attributes given an AST 6097 // representation, not a parser representation. 6098 if (D) 6099 // FIXME: What to pass instead of TUScope? 6100 ProcessDeclAttributes(TUScope, NewFD, *D); 6101 6102 if (T.isObjCGCWeak()) 6103 Diag(Loc, diag::warn_attribute_weak_on_field); 6104 6105 NewFD->setAccess(AS); 6106 6107 // C++ [dcl.init.aggr]p1: 6108 // An aggregate is an array or a class (clause 9) with [...] no 6109 // private or protected non-static data members (clause 11). 6110 // A POD must be an aggregate. 6111 if (getLangOptions().CPlusPlus && 6112 (AS == AS_private || AS == AS_protected)) { 6113 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 6114 CXXRecord->setAggregate(false); 6115 CXXRecord->setPOD(false); 6116 } 6117 6118 return NewFD; 6119} 6120 6121bool Sema::CheckNontrivialField(FieldDecl *FD) { 6122 assert(FD); 6123 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6124 6125 if (FD->isInvalidDecl()) 6126 return true; 6127 6128 QualType EltTy = Context.getBaseElementType(FD->getType()); 6129 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6130 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6131 if (RDecl->getDefinition()) { 6132 // We check for copy constructors before constructors 6133 // because otherwise we'll never get complaints about 6134 // copy constructors. 6135 6136 CXXSpecialMember member = CXXInvalid; 6137 if (!RDecl->hasTrivialCopyConstructor()) 6138 member = CXXCopyConstructor; 6139 else if (!RDecl->hasTrivialConstructor()) 6140 member = CXXConstructor; 6141 else if (!RDecl->hasTrivialCopyAssignment()) 6142 member = CXXCopyAssignment; 6143 else if (!RDecl->hasTrivialDestructor()) 6144 member = CXXDestructor; 6145 6146 if (member != CXXInvalid) { 6147 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6148 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6149 DiagnoseNontrivial(RT, member); 6150 return true; 6151 } 6152 } 6153 } 6154 6155 return false; 6156} 6157 6158/// DiagnoseNontrivial - Given that a class has a non-trivial 6159/// special member, figure out why. 6160void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6161 QualType QT(T, 0U); 6162 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6163 6164 // Check whether the member was user-declared. 6165 switch (member) { 6166 case CXXInvalid: 6167 break; 6168 6169 case CXXConstructor: 6170 if (RD->hasUserDeclaredConstructor()) { 6171 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6172 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6173 const FunctionDecl *body = 0; 6174 ci->hasBody(body); 6175 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6176 SourceLocation CtorLoc = ci->getLocation(); 6177 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6178 return; 6179 } 6180 } 6181 6182 assert(0 && "found no user-declared constructors"); 6183 return; 6184 } 6185 break; 6186 6187 case CXXCopyConstructor: 6188 if (RD->hasUserDeclaredCopyConstructor()) { 6189 SourceLocation CtorLoc = 6190 RD->getCopyConstructor(Context, 0)->getLocation(); 6191 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6192 return; 6193 } 6194 break; 6195 6196 case CXXCopyAssignment: 6197 if (RD->hasUserDeclaredCopyAssignment()) { 6198 // FIXME: this should use the location of the copy 6199 // assignment, not the type. 6200 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6201 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6202 return; 6203 } 6204 break; 6205 6206 case CXXDestructor: 6207 if (RD->hasUserDeclaredDestructor()) { 6208 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6209 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6210 return; 6211 } 6212 break; 6213 } 6214 6215 typedef CXXRecordDecl::base_class_iterator base_iter; 6216 6217 // Virtual bases and members inhibit trivial copying/construction, 6218 // but not trivial destruction. 6219 if (member != CXXDestructor) { 6220 // Check for virtual bases. vbases includes indirect virtual bases, 6221 // so we just iterate through the direct bases. 6222 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6223 if (bi->isVirtual()) { 6224 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6225 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6226 return; 6227 } 6228 6229 // Check for virtual methods. 6230 typedef CXXRecordDecl::method_iterator meth_iter; 6231 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6232 ++mi) { 6233 if (mi->isVirtual()) { 6234 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6235 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6236 return; 6237 } 6238 } 6239 } 6240 6241 bool (CXXRecordDecl::*hasTrivial)() const; 6242 switch (member) { 6243 case CXXConstructor: 6244 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6245 case CXXCopyConstructor: 6246 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6247 case CXXCopyAssignment: 6248 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6249 case CXXDestructor: 6250 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6251 default: 6252 assert(0 && "unexpected special member"); return; 6253 } 6254 6255 // Check for nontrivial bases (and recurse). 6256 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6257 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6258 assert(BaseRT && "Don't know how to handle dependent bases"); 6259 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6260 if (!(BaseRecTy->*hasTrivial)()) { 6261 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6262 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6263 DiagnoseNontrivial(BaseRT, member); 6264 return; 6265 } 6266 } 6267 6268 // Check for nontrivial members (and recurse). 6269 typedef RecordDecl::field_iterator field_iter; 6270 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6271 ++fi) { 6272 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6273 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6274 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6275 6276 if (!(EltRD->*hasTrivial)()) { 6277 SourceLocation FLoc = (*fi)->getLocation(); 6278 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6279 DiagnoseNontrivial(EltRT, member); 6280 return; 6281 } 6282 } 6283 } 6284 6285 assert(0 && "found no explanation for non-trivial member"); 6286} 6287 6288/// TranslateIvarVisibility - Translate visibility from a token ID to an 6289/// AST enum value. 6290static ObjCIvarDecl::AccessControl 6291TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6292 switch (ivarVisibility) { 6293 default: assert(0 && "Unknown visitibility kind"); 6294 case tok::objc_private: return ObjCIvarDecl::Private; 6295 case tok::objc_public: return ObjCIvarDecl::Public; 6296 case tok::objc_protected: return ObjCIvarDecl::Protected; 6297 case tok::objc_package: return ObjCIvarDecl::Package; 6298 } 6299} 6300 6301/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6302/// in order to create an IvarDecl object for it. 6303Decl *Sema::ActOnIvar(Scope *S, 6304 SourceLocation DeclStart, 6305 Decl *IntfDecl, 6306 Declarator &D, ExprTy *BitfieldWidth, 6307 tok::ObjCKeywordKind Visibility) { 6308 6309 IdentifierInfo *II = D.getIdentifier(); 6310 Expr *BitWidth = (Expr*)BitfieldWidth; 6311 SourceLocation Loc = DeclStart; 6312 if (II) Loc = D.getIdentifierLoc(); 6313 6314 // FIXME: Unnamed fields can be handled in various different ways, for 6315 // example, unnamed unions inject all members into the struct namespace! 6316 6317 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6318 QualType T = TInfo->getType(); 6319 6320 if (BitWidth) { 6321 // 6.7.2.1p3, 6.7.2.1p4 6322 if (VerifyBitField(Loc, II, T, BitWidth)) { 6323 D.setInvalidType(); 6324 DeleteExpr(BitWidth); 6325 BitWidth = 0; 6326 } 6327 } else { 6328 // Not a bitfield. 6329 6330 // validate II. 6331 6332 } 6333 if (T->isReferenceType()) { 6334 Diag(Loc, diag::err_ivar_reference_type); 6335 D.setInvalidType(); 6336 } 6337 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6338 // than a variably modified type. 6339 else if (T->isVariablyModifiedType()) { 6340 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6341 D.setInvalidType(); 6342 } 6343 6344 // Get the visibility (access control) for this ivar. 6345 ObjCIvarDecl::AccessControl ac = 6346 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6347 : ObjCIvarDecl::None; 6348 // Must set ivar's DeclContext to its enclosing interface. 6349 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6350 ObjCContainerDecl *EnclosingContext; 6351 if (ObjCImplementationDecl *IMPDecl = 6352 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6353 // Case of ivar declared in an implementation. Context is that of its class. 6354 EnclosingContext = IMPDecl->getClassInterface(); 6355 assert(EnclosingContext && "Implementation has no class interface!"); 6356 } else { 6357 if (ObjCCategoryDecl *CDecl = 6358 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6359 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6360 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6361 return 0; 6362 } 6363 } 6364 EnclosingContext = EnclosingDecl; 6365 } 6366 6367 // Construct the decl. 6368 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6369 EnclosingContext, Loc, II, T, 6370 TInfo, ac, (Expr *)BitfieldWidth); 6371 6372 if (II) { 6373 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6374 ForRedeclaration); 6375 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6376 && !isa<TagDecl>(PrevDecl)) { 6377 Diag(Loc, diag::err_duplicate_member) << II; 6378 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6379 NewID->setInvalidDecl(); 6380 } 6381 } 6382 6383 // Process attributes attached to the ivar. 6384 ProcessDeclAttributes(S, NewID, D); 6385 6386 if (D.isInvalidType()) 6387 NewID->setInvalidDecl(); 6388 6389 if (II) { 6390 // FIXME: When interfaces are DeclContexts, we'll need to add 6391 // these to the interface. 6392 S->AddDecl(NewID); 6393 IdResolver.AddDecl(NewID); 6394 } 6395 6396 return NewID; 6397} 6398 6399void Sema::ActOnFields(Scope* S, 6400 SourceLocation RecLoc, Decl *EnclosingDecl, 6401 Decl **Fields, unsigned NumFields, 6402 SourceLocation LBrac, SourceLocation RBrac, 6403 AttributeList *Attr) { 6404 assert(EnclosingDecl && "missing record or interface decl"); 6405 6406 // If the decl this is being inserted into is invalid, then it may be a 6407 // redeclaration or some other bogus case. Don't try to add fields to it. 6408 if (EnclosingDecl->isInvalidDecl()) { 6409 // FIXME: Deallocate fields? 6410 return; 6411 } 6412 6413 6414 // Verify that all the fields are okay. 6415 unsigned NumNamedMembers = 0; 6416 llvm::SmallVector<FieldDecl*, 32> RecFields; 6417 6418 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6419 for (unsigned i = 0; i != NumFields; ++i) { 6420 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6421 6422 // Get the type for the field. 6423 Type *FDTy = FD->getType().getTypePtr(); 6424 6425 if (!FD->isAnonymousStructOrUnion()) { 6426 // Remember all fields written by the user. 6427 RecFields.push_back(FD); 6428 } 6429 6430 // If the field is already invalid for some reason, don't emit more 6431 // diagnostics about it. 6432 if (FD->isInvalidDecl()) { 6433 EnclosingDecl->setInvalidDecl(); 6434 continue; 6435 } 6436 6437 // C99 6.7.2.1p2: 6438 // A structure or union shall not contain a member with 6439 // incomplete or function type (hence, a structure shall not 6440 // contain an instance of itself, but may contain a pointer to 6441 // an instance of itself), except that the last member of a 6442 // structure with more than one named member may have incomplete 6443 // array type; such a structure (and any union containing, 6444 // possibly recursively, a member that is such a structure) 6445 // shall not be a member of a structure or an element of an 6446 // array. 6447 if (FDTy->isFunctionType()) { 6448 // Field declared as a function. 6449 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6450 << FD->getDeclName(); 6451 FD->setInvalidDecl(); 6452 EnclosingDecl->setInvalidDecl(); 6453 continue; 6454 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6455 Record && Record->isStruct()) { 6456 // Flexible array member. 6457 if (NumNamedMembers < 1) { 6458 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6459 << FD->getDeclName(); 6460 FD->setInvalidDecl(); 6461 EnclosingDecl->setInvalidDecl(); 6462 continue; 6463 } 6464 if (!FD->getType()->isDependentType() && 6465 !Context.getBaseElementType(FD->getType())->isPODType()) { 6466 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6467 << FD->getDeclName() << FD->getType(); 6468 FD->setInvalidDecl(); 6469 EnclosingDecl->setInvalidDecl(); 6470 continue; 6471 } 6472 6473 // Okay, we have a legal flexible array member at the end of the struct. 6474 if (Record) 6475 Record->setHasFlexibleArrayMember(true); 6476 } else if (!FDTy->isDependentType() && 6477 RequireCompleteType(FD->getLocation(), FD->getType(), 6478 diag::err_field_incomplete)) { 6479 // Incomplete type 6480 FD->setInvalidDecl(); 6481 EnclosingDecl->setInvalidDecl(); 6482 continue; 6483 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6484 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6485 // If this is a member of a union, then entire union becomes "flexible". 6486 if (Record && Record->isUnion()) { 6487 Record->setHasFlexibleArrayMember(true); 6488 } else { 6489 // If this is a struct/class and this is not the last element, reject 6490 // it. Note that GCC supports variable sized arrays in the middle of 6491 // structures. 6492 if (i != NumFields-1) 6493 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6494 << FD->getDeclName() << FD->getType(); 6495 else { 6496 // We support flexible arrays at the end of structs in 6497 // other structs as an extension. 6498 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6499 << FD->getDeclName(); 6500 if (Record) 6501 Record->setHasFlexibleArrayMember(true); 6502 } 6503 } 6504 } 6505 if (Record && FDTTy->getDecl()->hasObjectMember()) 6506 Record->setHasObjectMember(true); 6507 } else if (FDTy->isObjCObjectType()) { 6508 /// A field cannot be an Objective-c object 6509 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6510 FD->setInvalidDecl(); 6511 EnclosingDecl->setInvalidDecl(); 6512 continue; 6513 } else if (getLangOptions().ObjC1 && 6514 getLangOptions().getGCMode() != LangOptions::NonGC && 6515 Record && 6516 (FD->getType()->isObjCObjectPointerType() || 6517 FD->getType().isObjCGCStrong())) 6518 Record->setHasObjectMember(true); 6519 else if (Context.getAsArrayType(FD->getType())) { 6520 QualType BaseType = Context.getBaseElementType(FD->getType()); 6521 if (Record && BaseType->isRecordType() && 6522 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6523 Record->setHasObjectMember(true); 6524 } 6525 // Keep track of the number of named members. 6526 if (FD->getIdentifier()) 6527 ++NumNamedMembers; 6528 } 6529 6530 // Okay, we successfully defined 'Record'. 6531 if (Record) { 6532 Record->completeDefinition(); 6533 } else { 6534 ObjCIvarDecl **ClsFields = 6535 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6536 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6537 ID->setLocEnd(RBrac); 6538 // Add ivar's to class's DeclContext. 6539 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6540 ClsFields[i]->setLexicalDeclContext(ID); 6541 ID->addDecl(ClsFields[i]); 6542 } 6543 // Must enforce the rule that ivars in the base classes may not be 6544 // duplicates. 6545 if (ID->getSuperClass()) 6546 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6547 } else if (ObjCImplementationDecl *IMPDecl = 6548 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6549 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6550 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6551 // Ivar declared in @implementation never belongs to the implementation. 6552 // Only it is in implementation's lexical context. 6553 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6554 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6555 } else if (ObjCCategoryDecl *CDecl = 6556 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6557 // case of ivars in class extension; all other cases have been 6558 // reported as errors elsewhere. 6559 // FIXME. Class extension does not have a LocEnd field. 6560 // CDecl->setLocEnd(RBrac); 6561 // Add ivar's to class extension's DeclContext. 6562 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6563 ClsFields[i]->setLexicalDeclContext(CDecl); 6564 CDecl->addDecl(ClsFields[i]); 6565 } 6566 } 6567 } 6568 6569 if (Attr) 6570 ProcessDeclAttributeList(S, Record, Attr); 6571 6572 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6573 // set the visibility of this record. 6574 if (Record && !Record->getDeclContext()->isRecord()) 6575 AddPushedVisibilityAttribute(Record); 6576} 6577 6578/// \brief Determine whether the given integral value is representable within 6579/// the given type T. 6580static bool isRepresentableIntegerValue(ASTContext &Context, 6581 llvm::APSInt &Value, 6582 QualType T) { 6583 assert(T->isIntegralType(Context) && "Integral type required!"); 6584 unsigned BitWidth = Context.getIntWidth(T); 6585 6586 if (Value.isUnsigned() || Value.isNonNegative()) 6587 return Value.getActiveBits() < BitWidth; 6588 6589 return Value.getMinSignedBits() <= BitWidth; 6590} 6591 6592// \brief Given an integral type, return the next larger integral type 6593// (or a NULL type of no such type exists). 6594static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6595 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6596 // enum checking below. 6597 assert(T->isIntegralType(Context) && "Integral type required!"); 6598 const unsigned NumTypes = 4; 6599 QualType SignedIntegralTypes[NumTypes] = { 6600 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6601 }; 6602 QualType UnsignedIntegralTypes[NumTypes] = { 6603 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6604 Context.UnsignedLongLongTy 6605 }; 6606 6607 unsigned BitWidth = Context.getTypeSize(T); 6608 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6609 : UnsignedIntegralTypes; 6610 for (unsigned I = 0; I != NumTypes; ++I) 6611 if (Context.getTypeSize(Types[I]) > BitWidth) 6612 return Types[I]; 6613 6614 return QualType(); 6615} 6616 6617EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6618 EnumConstantDecl *LastEnumConst, 6619 SourceLocation IdLoc, 6620 IdentifierInfo *Id, 6621 ExprArg val) { 6622 Expr *Val = (Expr *)val.get(); 6623 6624 unsigned IntWidth = Context.Target.getIntWidth(); 6625 llvm::APSInt EnumVal(IntWidth); 6626 QualType EltTy; 6627 if (Val) { 6628 if (Enum->isDependentType() || Val->isTypeDependent()) 6629 EltTy = Context.DependentTy; 6630 else { 6631 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6632 SourceLocation ExpLoc; 6633 if (!Val->isValueDependent() && 6634 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6635 Val = 0; 6636 } else { 6637 if (!getLangOptions().CPlusPlus) { 6638 // C99 6.7.2.2p2: 6639 // The expression that defines the value of an enumeration constant 6640 // shall be an integer constant expression that has a value 6641 // representable as an int. 6642 6643 // Complain if the value is not representable in an int. 6644 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6645 Diag(IdLoc, diag::ext_enum_value_not_int) 6646 << EnumVal.toString(10) << Val->getSourceRange() 6647 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6648 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6649 // Force the type of the expression to 'int'. 6650 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6651 6652 if (Val != val.get()) { 6653 val.release(); 6654 val = Val; 6655 } 6656 } 6657 } 6658 6659 // C++0x [dcl.enum]p5: 6660 // If the underlying type is not fixed, the type of each enumerator 6661 // is the type of its initializing value: 6662 // - If an initializer is specified for an enumerator, the 6663 // initializing value has the same type as the expression. 6664 EltTy = Val->getType(); 6665 } 6666 } 6667 } 6668 6669 if (!Val) { 6670 if (Enum->isDependentType()) 6671 EltTy = Context.DependentTy; 6672 else if (!LastEnumConst) { 6673 // C++0x [dcl.enum]p5: 6674 // If the underlying type is not fixed, the type of each enumerator 6675 // is the type of its initializing value: 6676 // - If no initializer is specified for the first enumerator, the 6677 // initializing value has an unspecified integral type. 6678 // 6679 // GCC uses 'int' for its unspecified integral type, as does 6680 // C99 6.7.2.2p3. 6681 EltTy = Context.IntTy; 6682 } else { 6683 // Assign the last value + 1. 6684 EnumVal = LastEnumConst->getInitVal(); 6685 ++EnumVal; 6686 EltTy = LastEnumConst->getType(); 6687 6688 // Check for overflow on increment. 6689 if (EnumVal < LastEnumConst->getInitVal()) { 6690 // C++0x [dcl.enum]p5: 6691 // If the underlying type is not fixed, the type of each enumerator 6692 // is the type of its initializing value: 6693 // 6694 // - Otherwise the type of the initializing value is the same as 6695 // the type of the initializing value of the preceding enumerator 6696 // unless the incremented value is not representable in that type, 6697 // in which case the type is an unspecified integral type 6698 // sufficient to contain the incremented value. If no such type 6699 // exists, the program is ill-formed. 6700 QualType T = getNextLargerIntegralType(Context, EltTy); 6701 if (T.isNull()) { 6702 // There is no integral type larger enough to represent this 6703 // value. Complain, then allow the value to wrap around. 6704 EnumVal = LastEnumConst->getInitVal(); 6705 EnumVal.zext(EnumVal.getBitWidth() * 2); 6706 Diag(IdLoc, diag::warn_enumerator_too_large) 6707 << EnumVal.toString(10); 6708 } else { 6709 EltTy = T; 6710 } 6711 6712 // Retrieve the last enumerator's value, extent that type to the 6713 // type that is supposed to be large enough to represent the incremented 6714 // value, then increment. 6715 EnumVal = LastEnumConst->getInitVal(); 6716 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6717 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6718 ++EnumVal; 6719 6720 // If we're not in C++, diagnose the overflow of enumerator values, 6721 // which in C99 means that the enumerator value is not representable in 6722 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6723 // permits enumerator values that are representable in some larger 6724 // integral type. 6725 if (!getLangOptions().CPlusPlus && !T.isNull()) 6726 Diag(IdLoc, diag::warn_enum_value_overflow); 6727 } else if (!getLangOptions().CPlusPlus && 6728 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6729 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6730 Diag(IdLoc, diag::ext_enum_value_not_int) 6731 << EnumVal.toString(10) << 1; 6732 } 6733 } 6734 } 6735 6736 if (!EltTy->isDependentType()) { 6737 // Make the enumerator value match the signedness and size of the 6738 // enumerator's type. 6739 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6740 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6741 } 6742 6743 val.release(); 6744 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6745 Val, EnumVal); 6746} 6747 6748 6749Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 6750 Decl *lastEnumConst, 6751 SourceLocation IdLoc, 6752 IdentifierInfo *Id, 6753 SourceLocation EqualLoc, ExprTy *val) { 6754 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 6755 EnumConstantDecl *LastEnumConst = 6756 cast_or_null<EnumConstantDecl>(lastEnumConst); 6757 Expr *Val = static_cast<Expr*>(val); 6758 6759 // The scope passed in may not be a decl scope. Zip up the scope tree until 6760 // we find one that is. 6761 S = getNonFieldDeclScope(S); 6762 6763 // Verify that there isn't already something declared with this name in this 6764 // scope. 6765 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6766 ForRedeclaration); 6767 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6768 // Maybe we will complain about the shadowed template parameter. 6769 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6770 // Just pretend that we didn't see the previous declaration. 6771 PrevDecl = 0; 6772 } 6773 6774 if (PrevDecl) { 6775 // When in C++, we may get a TagDecl with the same name; in this case the 6776 // enum constant will 'hide' the tag. 6777 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6778 "Received TagDecl when not in C++!"); 6779 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6780 if (isa<EnumConstantDecl>(PrevDecl)) 6781 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6782 else 6783 Diag(IdLoc, diag::err_redefinition) << Id; 6784 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6785 return 0; 6786 } 6787 } 6788 6789 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6790 IdLoc, Id, Owned(Val)); 6791 6792 // Register this decl in the current scope stack. 6793 if (New) { 6794 New->setAccess(TheEnumDecl->getAccess()); 6795 PushOnScopeChains(New, S); 6796 } 6797 6798 return New; 6799} 6800 6801void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6802 SourceLocation RBraceLoc, Decl *EnumDeclX, 6803 Decl **Elements, unsigned NumElements, 6804 Scope *S, AttributeList *Attr) { 6805 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 6806 QualType EnumType = Context.getTypeDeclType(Enum); 6807 6808 if (Attr) 6809 ProcessDeclAttributeList(S, Enum, Attr); 6810 6811 if (Enum->isDependentType()) { 6812 for (unsigned i = 0; i != NumElements; ++i) { 6813 EnumConstantDecl *ECD = 6814 cast_or_null<EnumConstantDecl>(Elements[i]); 6815 if (!ECD) continue; 6816 6817 ECD->setType(EnumType); 6818 } 6819 6820 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6821 return; 6822 } 6823 6824 // TODO: If the result value doesn't fit in an int, it must be a long or long 6825 // long value. ISO C does not support this, but GCC does as an extension, 6826 // emit a warning. 6827 unsigned IntWidth = Context.Target.getIntWidth(); 6828 unsigned CharWidth = Context.Target.getCharWidth(); 6829 unsigned ShortWidth = Context.Target.getShortWidth(); 6830 6831 // Verify that all the values are okay, compute the size of the values, and 6832 // reverse the list. 6833 unsigned NumNegativeBits = 0; 6834 unsigned NumPositiveBits = 0; 6835 6836 // Keep track of whether all elements have type int. 6837 bool AllElementsInt = true; 6838 6839 for (unsigned i = 0; i != NumElements; ++i) { 6840 EnumConstantDecl *ECD = 6841 cast_or_null<EnumConstantDecl>(Elements[i]); 6842 if (!ECD) continue; // Already issued a diagnostic. 6843 6844 const llvm::APSInt &InitVal = ECD->getInitVal(); 6845 6846 // Keep track of the size of positive and negative values. 6847 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6848 NumPositiveBits = std::max(NumPositiveBits, 6849 (unsigned)InitVal.getActiveBits()); 6850 else 6851 NumNegativeBits = std::max(NumNegativeBits, 6852 (unsigned)InitVal.getMinSignedBits()); 6853 6854 // Keep track of whether every enum element has type int (very commmon). 6855 if (AllElementsInt) 6856 AllElementsInt = ECD->getType() == Context.IntTy; 6857 } 6858 6859 // Figure out the type that should be used for this enum. 6860 // FIXME: Support -fshort-enums. 6861 QualType BestType; 6862 unsigned BestWidth; 6863 6864 // C++0x N3000 [conv.prom]p3: 6865 // An rvalue of an unscoped enumeration type whose underlying 6866 // type is not fixed can be converted to an rvalue of the first 6867 // of the following types that can represent all the values of 6868 // the enumeration: int, unsigned int, long int, unsigned long 6869 // int, long long int, or unsigned long long int. 6870 // C99 6.4.4.3p2: 6871 // An identifier declared as an enumeration constant has type int. 6872 // The C99 rule is modified by a gcc extension 6873 QualType BestPromotionType; 6874 6875 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6876 6877 if (NumNegativeBits) { 6878 // If there is a negative value, figure out the smallest integer type (of 6879 // int/long/longlong) that fits. 6880 // If it's packed, check also if it fits a char or a short. 6881 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6882 BestType = Context.SignedCharTy; 6883 BestWidth = CharWidth; 6884 } else if (Packed && NumNegativeBits <= ShortWidth && 6885 NumPositiveBits < ShortWidth) { 6886 BestType = Context.ShortTy; 6887 BestWidth = ShortWidth; 6888 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6889 BestType = Context.IntTy; 6890 BestWidth = IntWidth; 6891 } else { 6892 BestWidth = Context.Target.getLongWidth(); 6893 6894 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6895 BestType = Context.LongTy; 6896 } else { 6897 BestWidth = Context.Target.getLongLongWidth(); 6898 6899 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6900 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6901 BestType = Context.LongLongTy; 6902 } 6903 } 6904 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6905 } else { 6906 // If there is no negative value, figure out the smallest type that fits 6907 // all of the enumerator values. 6908 // If it's packed, check also if it fits a char or a short. 6909 if (Packed && NumPositiveBits <= CharWidth) { 6910 BestType = Context.UnsignedCharTy; 6911 BestPromotionType = Context.IntTy; 6912 BestWidth = CharWidth; 6913 } else if (Packed && NumPositiveBits <= ShortWidth) { 6914 BestType = Context.UnsignedShortTy; 6915 BestPromotionType = Context.IntTy; 6916 BestWidth = ShortWidth; 6917 } else if (NumPositiveBits <= IntWidth) { 6918 BestType = Context.UnsignedIntTy; 6919 BestWidth = IntWidth; 6920 BestPromotionType 6921 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6922 ? Context.UnsignedIntTy : Context.IntTy; 6923 } else if (NumPositiveBits <= 6924 (BestWidth = Context.Target.getLongWidth())) { 6925 BestType = Context.UnsignedLongTy; 6926 BestPromotionType 6927 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6928 ? Context.UnsignedLongTy : Context.LongTy; 6929 } else { 6930 BestWidth = Context.Target.getLongLongWidth(); 6931 assert(NumPositiveBits <= BestWidth && 6932 "How could an initializer get larger than ULL?"); 6933 BestType = Context.UnsignedLongLongTy; 6934 BestPromotionType 6935 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6936 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6937 } 6938 } 6939 6940 // Loop over all of the enumerator constants, changing their types to match 6941 // the type of the enum if needed. 6942 for (unsigned i = 0; i != NumElements; ++i) { 6943 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 6944 if (!ECD) continue; // Already issued a diagnostic. 6945 6946 // Standard C says the enumerators have int type, but we allow, as an 6947 // extension, the enumerators to be larger than int size. If each 6948 // enumerator value fits in an int, type it as an int, otherwise type it the 6949 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6950 // that X has type 'int', not 'unsigned'. 6951 6952 // Determine whether the value fits into an int. 6953 llvm::APSInt InitVal = ECD->getInitVal(); 6954 6955 // If it fits into an integer type, force it. Otherwise force it to match 6956 // the enum decl type. 6957 QualType NewTy; 6958 unsigned NewWidth; 6959 bool NewSign; 6960 if (!getLangOptions().CPlusPlus && 6961 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6962 NewTy = Context.IntTy; 6963 NewWidth = IntWidth; 6964 NewSign = true; 6965 } else if (ECD->getType() == BestType) { 6966 // Already the right type! 6967 if (getLangOptions().CPlusPlus) 6968 // C++ [dcl.enum]p4: Following the closing brace of an 6969 // enum-specifier, each enumerator has the type of its 6970 // enumeration. 6971 ECD->setType(EnumType); 6972 continue; 6973 } else { 6974 NewTy = BestType; 6975 NewWidth = BestWidth; 6976 NewSign = BestType->isSignedIntegerType(); 6977 } 6978 6979 // Adjust the APSInt value. 6980 InitVal.extOrTrunc(NewWidth); 6981 InitVal.setIsSigned(NewSign); 6982 ECD->setInitVal(InitVal); 6983 6984 // Adjust the Expr initializer and type. 6985 if (ECD->getInitExpr()) 6986 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 6987 CastExpr::CK_IntegralCast, 6988 ECD->getInitExpr(), 6989 /*base paths*/ 0, 6990 ImplicitCastExpr::RValue)); 6991 if (getLangOptions().CPlusPlus) 6992 // C++ [dcl.enum]p4: Following the closing brace of an 6993 // enum-specifier, each enumerator has the type of its 6994 // enumeration. 6995 ECD->setType(EnumType); 6996 else 6997 ECD->setType(NewTy); 6998 } 6999 7000 Enum->completeDefinition(BestType, BestPromotionType, 7001 NumPositiveBits, NumNegativeBits); 7002} 7003 7004Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, ExprArg expr) { 7005 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 7006 7007 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7008 Loc, AsmString); 7009 CurContext->addDecl(New); 7010 return New; 7011} 7012 7013void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7014 SourceLocation PragmaLoc, 7015 SourceLocation NameLoc) { 7016 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7017 7018 if (PrevDecl) { 7019 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7020 } else { 7021 (void)WeakUndeclaredIdentifiers.insert( 7022 std::pair<IdentifierInfo*,WeakInfo> 7023 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7024 } 7025} 7026 7027void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7028 IdentifierInfo* AliasName, 7029 SourceLocation PragmaLoc, 7030 SourceLocation NameLoc, 7031 SourceLocation AliasNameLoc) { 7032 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7033 LookupOrdinaryName); 7034 WeakInfo W = WeakInfo(Name, NameLoc); 7035 7036 if (PrevDecl) { 7037 if (!PrevDecl->hasAttr<AliasAttr>()) 7038 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7039 DeclApplyPragmaWeak(TUScope, ND, W); 7040 } else { 7041 (void)WeakUndeclaredIdentifiers.insert( 7042 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7043 } 7044} 7045