SemaDecl.cpp revision 0b7e678a11ece4288dc01aebb5b17e5eef8f8d2d
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "TypeLocBuilder.h" 21#include "clang/AST/APValue.h" 22#include "clang/AST/ASTConsumer.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclCXX.h" 26#include "clang/AST/DeclObjC.h" 27#include "clang/AST/DeclTemplate.h" 28#include "clang/AST/ExprCXX.h" 29#include "clang/AST/StmtCXX.h" 30#include "clang/AST/CharUnits.h" 31#include "clang/Sema/DeclSpec.h" 32#include "clang/Sema/ParsedTemplate.h" 33#include "clang/Parse/ParseDiagnostic.h" 34#include "clang/Basic/PartialDiagnostic.h" 35#include "clang/Basic/SourceManager.h" 36#include "clang/Basic/TargetInfo.h" 37// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 38#include "clang/Lex/Preprocessor.h" 39#include "clang/Lex/HeaderSearch.h" 40#include "llvm/ADT/Triple.h" 41#include <algorithm> 42#include <cstring> 43#include <functional> 44using namespace clang; 45using namespace sema; 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. 62ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, CXXScopeSpec *SS, 64 bool isClassName, bool HasTrailingDot, 65 ParsedType ObjectTypePtr, 66 bool WantNontrivialTypeSourceInfo) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = ObjectTypePtr.get(); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return ParsedType(); 89 90 // We know from the grammar that this name refers to a type, 91 // so build a dependent node to describe the type. 92 if (WantNontrivialTypeSourceInfo) 93 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 94 95 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 96 QualType T = 97 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 98 II, NameLoc); 99 100 return ParsedType::make(T); 101 } 102 103 return ParsedType(); 104 } 105 106 if (!LookupCtx->isDependentContext() && 107 RequireCompleteDeclContext(*SS, LookupCtx)) 108 return ParsedType(); 109 } 110 111 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 112 // lookup for class-names. 113 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 114 LookupOrdinaryName; 115 LookupResult Result(*this, &II, NameLoc, Kind); 116 if (LookupCtx) { 117 // Perform "qualified" name lookup into the declaration context we 118 // computed, which is either the type of the base of a member access 119 // expression or the declaration context associated with a prior 120 // nested-name-specifier. 121 LookupQualifiedName(Result, LookupCtx); 122 123 if (ObjectTypePtr && Result.empty()) { 124 // C++ [basic.lookup.classref]p3: 125 // If the unqualified-id is ~type-name, the type-name is looked up 126 // in the context of the entire postfix-expression. If the type T of 127 // the object expression is of a class type C, the type-name is also 128 // looked up in the scope of class C. At least one of the lookups shall 129 // find a name that refers to (possibly cv-qualified) T. 130 LookupName(Result, S); 131 } 132 } else { 133 // Perform unqualified name lookup. 134 LookupName(Result, S); 135 } 136 137 NamedDecl *IIDecl = 0; 138 switch (Result.getResultKind()) { 139 case LookupResult::NotFound: 140 case LookupResult::NotFoundInCurrentInstantiation: 141 case LookupResult::FoundOverloaded: 142 case LookupResult::FoundUnresolvedValue: 143 Result.suppressDiagnostics(); 144 return ParsedType(); 145 146 case LookupResult::Ambiguous: 147 // Recover from type-hiding ambiguities by hiding the type. We'll 148 // do the lookup again when looking for an object, and we can 149 // diagnose the error then. If we don't do this, then the error 150 // about hiding the type will be immediately followed by an error 151 // that only makes sense if the identifier was treated like a type. 152 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 153 Result.suppressDiagnostics(); 154 return ParsedType(); 155 } 156 157 // Look to see if we have a type anywhere in the list of results. 158 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 159 Res != ResEnd; ++Res) { 160 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 161 if (!IIDecl || 162 (*Res)->getLocation().getRawEncoding() < 163 IIDecl->getLocation().getRawEncoding()) 164 IIDecl = *Res; 165 } 166 } 167 168 if (!IIDecl) { 169 // None of the entities we found is a type, so there is no way 170 // to even assume that the result is a type. In this case, don't 171 // complain about the ambiguity. The parser will either try to 172 // perform this lookup again (e.g., as an object name), which 173 // will produce the ambiguity, or will complain that it expected 174 // a type name. 175 Result.suppressDiagnostics(); 176 return ParsedType(); 177 } 178 179 // We found a type within the ambiguous lookup; diagnose the 180 // ambiguity and then return that type. This might be the right 181 // answer, or it might not be, but it suppresses any attempt to 182 // perform the name lookup again. 183 break; 184 185 case LookupResult::Found: 186 IIDecl = Result.getFoundDecl(); 187 break; 188 } 189 190 assert(IIDecl && "Didn't find decl"); 191 192 QualType T; 193 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 194 DiagnoseUseOfDecl(IIDecl, NameLoc); 195 196 if (T.isNull()) 197 T = Context.getTypeDeclType(TD); 198 199 if (SS && SS->isNotEmpty()) { 200 if (WantNontrivialTypeSourceInfo) { 201 // Construct a type with type-source information. 202 TypeLocBuilder Builder; 203 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 204 205 T = getElaboratedType(ETK_None, *SS, T); 206 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 207 ElabTL.setKeywordLoc(SourceLocation()); 208 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 209 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 210 } else { 211 T = getElaboratedType(ETK_None, *SS, T); 212 } 213 } 214 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 215 (void)DiagnoseUseOfDecl(IDecl, NameLoc); 216 if (!HasTrailingDot) 217 T = Context.getObjCInterfaceType(IDecl); 218 } 219 220 if (T.isNull()) { 221 // If it's not plausibly a type, suppress diagnostics. 222 Result.suppressDiagnostics(); 223 return ParsedType(); 224 } 225 return ParsedType::make(T); 226} 227 228/// isTagName() - This method is called *for error recovery purposes only* 229/// to determine if the specified name is a valid tag name ("struct foo"). If 230/// so, this returns the TST for the tag corresponding to it (TST_enum, 231/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 232/// where the user forgot to specify the tag. 233DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 234 // Do a tag name lookup in this scope. 235 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 236 LookupName(R, S, false); 237 R.suppressDiagnostics(); 238 if (R.getResultKind() == LookupResult::Found) 239 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 240 switch (TD->getTagKind()) { 241 default: return DeclSpec::TST_unspecified; 242 case TTK_Struct: return DeclSpec::TST_struct; 243 case TTK_Union: return DeclSpec::TST_union; 244 case TTK_Class: return DeclSpec::TST_class; 245 case TTK_Enum: return DeclSpec::TST_enum; 246 } 247 } 248 249 return DeclSpec::TST_unspecified; 250} 251 252bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 253 SourceLocation IILoc, 254 Scope *S, 255 CXXScopeSpec *SS, 256 ParsedType &SuggestedType) { 257 // We don't have anything to suggest (yet). 258 SuggestedType = ParsedType(); 259 260 // There may have been a typo in the name of the type. Look up typo 261 // results, in case we have something that we can suggest. 262 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 263 NotForRedeclaration); 264 265 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 266 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 267 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 268 !Result->isInvalidDecl()) { 269 // We found a similarly-named type or interface; suggest that. 270 if (!SS || !SS->isSet()) 271 Diag(IILoc, diag::err_unknown_typename_suggest) 272 << &II << Lookup.getLookupName() 273 << FixItHint::CreateReplacement(SourceRange(IILoc), 274 Result->getNameAsString()); 275 else if (DeclContext *DC = computeDeclContext(*SS, false)) 276 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 277 << &II << DC << Lookup.getLookupName() << SS->getRange() 278 << FixItHint::CreateReplacement(SourceRange(IILoc), 279 Result->getNameAsString()); 280 else 281 llvm_unreachable("could not have corrected a typo here"); 282 283 Diag(Result->getLocation(), diag::note_previous_decl) 284 << Result->getDeclName(); 285 286 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 287 false, false, ParsedType(), 288 /*NonTrivialTypeSourceInfo=*/true); 289 return true; 290 } 291 } else if (Lookup.empty()) { 292 // We corrected to a keyword. 293 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 294 Diag(IILoc, diag::err_unknown_typename_suggest) 295 << &II << Corrected; 296 return true; 297 } 298 } 299 300 if (getLangOptions().CPlusPlus) { 301 // See if II is a class template that the user forgot to pass arguments to. 302 UnqualifiedId Name; 303 Name.setIdentifier(&II, IILoc); 304 CXXScopeSpec EmptySS; 305 TemplateTy TemplateResult; 306 bool MemberOfUnknownSpecialization; 307 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 308 Name, ParsedType(), true, TemplateResult, 309 MemberOfUnknownSpecialization) == TNK_Type_template) { 310 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 311 Diag(IILoc, diag::err_template_missing_args) << TplName; 312 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 313 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 314 << TplDecl->getTemplateParameters()->getSourceRange(); 315 } 316 return true; 317 } 318 } 319 320 // FIXME: Should we move the logic that tries to recover from a missing tag 321 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 322 323 if (!SS || (!SS->isSet() && !SS->isInvalid())) 324 Diag(IILoc, diag::err_unknown_typename) << &II; 325 else if (DeclContext *DC = computeDeclContext(*SS, false)) 326 Diag(IILoc, diag::err_typename_nested_not_found) 327 << &II << DC << SS->getRange(); 328 else if (isDependentScopeSpecifier(*SS)) { 329 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 330 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 331 << SourceRange(SS->getRange().getBegin(), IILoc) 332 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 333 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 334 } else { 335 assert(SS && SS->isInvalid() && 336 "Invalid scope specifier has already been diagnosed"); 337 } 338 339 return true; 340} 341 342// Determines the context to return to after temporarily entering a 343// context. This depends in an unnecessarily complicated way on the 344// exact ordering of callbacks from the parser. 345DeclContext *Sema::getContainingDC(DeclContext *DC) { 346 347 // Functions defined inline within classes aren't parsed until we've 348 // finished parsing the top-level class, so the top-level class is 349 // the context we'll need to return to. 350 if (isa<FunctionDecl>(DC)) { 351 DC = DC->getLexicalParent(); 352 353 // A function not defined within a class will always return to its 354 // lexical context. 355 if (!isa<CXXRecordDecl>(DC)) 356 return DC; 357 358 // A C++ inline method/friend is parsed *after* the topmost class 359 // it was declared in is fully parsed ("complete"); the topmost 360 // class is the context we need to return to. 361 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 362 DC = RD; 363 364 // Return the declaration context of the topmost class the inline method is 365 // declared in. 366 return DC; 367 } 368 369 // ObjCMethodDecls are parsed (for some reason) outside the context 370 // of the class. 371 if (isa<ObjCMethodDecl>(DC)) 372 return DC->getLexicalParent()->getLexicalParent(); 373 374 return DC->getLexicalParent(); 375} 376 377void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 378 assert(getContainingDC(DC) == CurContext && 379 "The next DeclContext should be lexically contained in the current one."); 380 CurContext = DC; 381 S->setEntity(DC); 382} 383 384void Sema::PopDeclContext() { 385 assert(CurContext && "DeclContext imbalance!"); 386 387 CurContext = getContainingDC(CurContext); 388 assert(CurContext && "Popped translation unit!"); 389} 390 391/// EnterDeclaratorContext - Used when we must lookup names in the context 392/// of a declarator's nested name specifier. 393/// 394void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 395 // C++0x [basic.lookup.unqual]p13: 396 // A name used in the definition of a static data member of class 397 // X (after the qualified-id of the static member) is looked up as 398 // if the name was used in a member function of X. 399 // C++0x [basic.lookup.unqual]p14: 400 // If a variable member of a namespace is defined outside of the 401 // scope of its namespace then any name used in the definition of 402 // the variable member (after the declarator-id) is looked up as 403 // if the definition of the variable member occurred in its 404 // namespace. 405 // Both of these imply that we should push a scope whose context 406 // is the semantic context of the declaration. We can't use 407 // PushDeclContext here because that context is not necessarily 408 // lexically contained in the current context. Fortunately, 409 // the containing scope should have the appropriate information. 410 411 assert(!S->getEntity() && "scope already has entity"); 412 413#ifndef NDEBUG 414 Scope *Ancestor = S->getParent(); 415 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 416 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 417#endif 418 419 CurContext = DC; 420 S->setEntity(DC); 421} 422 423void Sema::ExitDeclaratorContext(Scope *S) { 424 assert(S->getEntity() == CurContext && "Context imbalance!"); 425 426 // Switch back to the lexical context. The safety of this is 427 // enforced by an assert in EnterDeclaratorContext. 428 Scope *Ancestor = S->getParent(); 429 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 430 CurContext = (DeclContext*) Ancestor->getEntity(); 431 432 // We don't need to do anything with the scope, which is going to 433 // disappear. 434} 435 436/// \brief Determine whether we allow overloading of the function 437/// PrevDecl with another declaration. 438/// 439/// This routine determines whether overloading is possible, not 440/// whether some new function is actually an overload. It will return 441/// true in C++ (where we can always provide overloads) or, as an 442/// extension, in C when the previous function is already an 443/// overloaded function declaration or has the "overloadable" 444/// attribute. 445static bool AllowOverloadingOfFunction(LookupResult &Previous, 446 ASTContext &Context) { 447 if (Context.getLangOptions().CPlusPlus) 448 return true; 449 450 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 451 return true; 452 453 return (Previous.getResultKind() == LookupResult::Found 454 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 455} 456 457/// Add this decl to the scope shadowed decl chains. 458void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 459 // Move up the scope chain until we find the nearest enclosing 460 // non-transparent context. The declaration will be introduced into this 461 // scope. 462 while (S->getEntity() && 463 ((DeclContext *)S->getEntity())->isTransparentContext()) 464 S = S->getParent(); 465 466 // Add scoped declarations into their context, so that they can be 467 // found later. Declarations without a context won't be inserted 468 // into any context. 469 if (AddToContext) 470 CurContext->addDecl(D); 471 472 // Out-of-line definitions shouldn't be pushed into scope in C++. 473 // Out-of-line variable and function definitions shouldn't even in C. 474 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 475 D->isOutOfLine()) 476 return; 477 478 // Template instantiations should also not be pushed into scope. 479 if (isa<FunctionDecl>(D) && 480 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 481 return; 482 483 // If this replaces anything in the current scope, 484 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 485 IEnd = IdResolver.end(); 486 for (; I != IEnd; ++I) { 487 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 488 S->RemoveDecl(*I); 489 IdResolver.RemoveDecl(*I); 490 491 // Should only need to replace one decl. 492 break; 493 } 494 } 495 496 S->AddDecl(D); 497 498 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { 499 // Implicitly-generated labels may end up getting generated in an order that 500 // isn't strictly lexical, which breaks name lookup. Be careful to insert 501 // the label at the appropriate place in the identifier chain. 502 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { 503 DeclContext *IDC = (*I)->getLexicalDeclContext(); 504 if (IDC == CurContext) { 505 if (!S->isDeclScope(*I)) 506 continue; 507 } else if (IDC->Encloses(CurContext)) 508 break; 509 } 510 511 IdResolver.InsertDeclAfter(I, D); 512 } else { 513 IdResolver.AddDecl(D); 514 } 515} 516 517bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, 518 bool ExplicitInstantiationOrSpecialization) { 519 return IdResolver.isDeclInScope(D, Ctx, Context, S, 520 ExplicitInstantiationOrSpecialization); 521} 522 523Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 524 DeclContext *TargetDC = DC->getPrimaryContext(); 525 do { 526 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 527 if (ScopeDC->getPrimaryContext() == TargetDC) 528 return S; 529 } while ((S = S->getParent())); 530 531 return 0; 532} 533 534static bool isOutOfScopePreviousDeclaration(NamedDecl *, 535 DeclContext*, 536 ASTContext&); 537 538/// Filters out lookup results that don't fall within the given scope 539/// as determined by isDeclInScope. 540static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 541 DeclContext *Ctx, Scope *S, 542 bool ConsiderLinkage, 543 bool ExplicitInstantiationOrSpecialization) { 544 LookupResult::Filter F = R.makeFilter(); 545 while (F.hasNext()) { 546 NamedDecl *D = F.next(); 547 548 if (SemaRef.isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) 549 continue; 550 551 if (ConsiderLinkage && 552 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 553 continue; 554 555 F.erase(); 556 } 557 558 F.done(); 559} 560 561static bool isUsingDecl(NamedDecl *D) { 562 return isa<UsingShadowDecl>(D) || 563 isa<UnresolvedUsingTypenameDecl>(D) || 564 isa<UnresolvedUsingValueDecl>(D); 565} 566 567/// Removes using shadow declarations from the lookup results. 568static void RemoveUsingDecls(LookupResult &R) { 569 LookupResult::Filter F = R.makeFilter(); 570 while (F.hasNext()) 571 if (isUsingDecl(F.next())) 572 F.erase(); 573 574 F.done(); 575} 576 577/// \brief Check for this common pattern: 578/// @code 579/// class S { 580/// S(const S&); // DO NOT IMPLEMENT 581/// void operator=(const S&); // DO NOT IMPLEMENT 582/// }; 583/// @endcode 584static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 585 // FIXME: Should check for private access too but access is set after we get 586 // the decl here. 587 if (D->isThisDeclarationADefinition()) 588 return false; 589 590 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 591 return CD->isCopyConstructor(); 592 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 593 return Method->isCopyAssignmentOperator(); 594 return false; 595} 596 597bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 598 assert(D); 599 600 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 601 return false; 602 603 // Ignore class templates. 604 if (D->getDeclContext()->isDependentContext() || 605 D->getLexicalDeclContext()->isDependentContext()) 606 return false; 607 608 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 609 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 610 return false; 611 612 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 613 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 614 return false; 615 } else { 616 // 'static inline' functions are used in headers; don't warn. 617 if (FD->getStorageClass() == SC_Static && 618 FD->isInlineSpecified()) 619 return false; 620 } 621 622 if (FD->isThisDeclarationADefinition() && 623 Context.DeclMustBeEmitted(FD)) 624 return false; 625 626 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 627 if (!VD->isFileVarDecl() || 628 VD->getType().isConstant(Context) || 629 Context.DeclMustBeEmitted(VD)) 630 return false; 631 632 if (VD->isStaticDataMember() && 633 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 634 return false; 635 636 } else { 637 return false; 638 } 639 640 // Only warn for unused decls internal to the translation unit. 641 if (D->getLinkage() == ExternalLinkage) 642 return false; 643 644 return true; 645} 646 647void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 648 if (!D) 649 return; 650 651 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 652 const FunctionDecl *First = FD->getFirstDeclaration(); 653 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 654 return; // First should already be in the vector. 655 } 656 657 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 658 const VarDecl *First = VD->getFirstDeclaration(); 659 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 660 return; // First should already be in the vector. 661 } 662 663 if (ShouldWarnIfUnusedFileScopedDecl(D)) 664 UnusedFileScopedDecls.push_back(D); 665 } 666 667static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 668 if (D->isInvalidDecl()) 669 return false; 670 671 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 672 return false; 673 674 if (isa<LabelDecl>(D)) 675 return true; 676 677 // White-list anything that isn't a local variable. 678 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 679 !D->getDeclContext()->isFunctionOrMethod()) 680 return false; 681 682 // Types of valid local variables should be complete, so this should succeed. 683 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 684 685 // White-list anything with an __attribute__((unused)) type. 686 QualType Ty = VD->getType(); 687 688 // Only look at the outermost level of typedef. 689 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 690 if (TT->getDecl()->hasAttr<UnusedAttr>()) 691 return false; 692 } 693 694 // If we failed to complete the type for some reason, or if the type is 695 // dependent, don't diagnose the variable. 696 if (Ty->isIncompleteType() || Ty->isDependentType()) 697 return false; 698 699 if (const TagType *TT = Ty->getAs<TagType>()) { 700 const TagDecl *Tag = TT->getDecl(); 701 if (Tag->hasAttr<UnusedAttr>()) 702 return false; 703 704 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 705 // FIXME: Checking for the presence of a user-declared constructor 706 // isn't completely accurate; we'd prefer to check that the initializer 707 // has no side effects. 708 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 709 return false; 710 } 711 } 712 713 // TODO: __attribute__((unused)) templates? 714 } 715 716 return true; 717} 718 719/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 720/// unless they are marked attr(unused). 721void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 722 if (!ShouldDiagnoseUnusedDecl(D)) 723 return; 724 725 unsigned DiagID; 726 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 727 DiagID = diag::warn_unused_exception_param; 728 else if (isa<LabelDecl>(D)) 729 DiagID = diag::warn_unused_label; 730 else 731 DiagID = diag::warn_unused_variable; 732 733 Diag(D->getLocation(), DiagID) << D->getDeclName(); 734} 735 736static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 737 // Verify that we have no forward references left. If so, there was a goto 738 // or address of a label taken, but no definition of it. Label fwd 739 // definitions are indicated with a null substmt. 740 if (L->getStmt() == 0) 741 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 742} 743 744void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 745 if (S->decl_empty()) return; 746 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 747 "Scope shouldn't contain decls!"); 748 749 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 750 I != E; ++I) { 751 Decl *TmpD = (*I); 752 assert(TmpD && "This decl didn't get pushed??"); 753 754 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 755 NamedDecl *D = cast<NamedDecl>(TmpD); 756 757 if (!D->getDeclName()) continue; 758 759 // Diagnose unused variables in this scope. 760 if (!S->hasErrorOccurred()) 761 DiagnoseUnusedDecl(D); 762 763 // If this was a forward reference to a label, verify it was defined. 764 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 765 CheckPoppedLabel(LD, *this); 766 767 // Remove this name from our lexical scope. 768 IdResolver.RemoveDecl(D); 769 } 770} 771 772/// \brief Look for an Objective-C class in the translation unit. 773/// 774/// \param Id The name of the Objective-C class we're looking for. If 775/// typo-correction fixes this name, the Id will be updated 776/// to the fixed name. 777/// 778/// \param IdLoc The location of the name in the translation unit. 779/// 780/// \param TypoCorrection If true, this routine will attempt typo correction 781/// if there is no class with the given name. 782/// 783/// \returns The declaration of the named Objective-C class, or NULL if the 784/// class could not be found. 785ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 786 SourceLocation IdLoc, 787 bool TypoCorrection) { 788 // The third "scope" argument is 0 since we aren't enabling lazy built-in 789 // creation from this context. 790 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 791 792 if (!IDecl && TypoCorrection) { 793 // Perform typo correction at the given location, but only if we 794 // find an Objective-C class name. 795 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 796 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 797 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 798 Diag(IdLoc, diag::err_undef_interface_suggest) 799 << Id << IDecl->getDeclName() 800 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 801 Diag(IDecl->getLocation(), diag::note_previous_decl) 802 << IDecl->getDeclName(); 803 804 Id = IDecl->getIdentifier(); 805 } 806 } 807 808 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 809} 810 811/// getNonFieldDeclScope - Retrieves the innermost scope, starting 812/// from S, where a non-field would be declared. This routine copes 813/// with the difference between C and C++ scoping rules in structs and 814/// unions. For example, the following code is well-formed in C but 815/// ill-formed in C++: 816/// @code 817/// struct S6 { 818/// enum { BAR } e; 819/// }; 820/// 821/// void test_S6() { 822/// struct S6 a; 823/// a.e = BAR; 824/// } 825/// @endcode 826/// For the declaration of BAR, this routine will return a different 827/// scope. The scope S will be the scope of the unnamed enumeration 828/// within S6. In C++, this routine will return the scope associated 829/// with S6, because the enumeration's scope is a transparent 830/// context but structures can contain non-field names. In C, this 831/// routine will return the translation unit scope, since the 832/// enumeration's scope is a transparent context and structures cannot 833/// contain non-field names. 834Scope *Sema::getNonFieldDeclScope(Scope *S) { 835 while (((S->getFlags() & Scope::DeclScope) == 0) || 836 (S->getEntity() && 837 ((DeclContext *)S->getEntity())->isTransparentContext()) || 838 (S->isClassScope() && !getLangOptions().CPlusPlus)) 839 S = S->getParent(); 840 return S; 841} 842 843/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 844/// file scope. lazily create a decl for it. ForRedeclaration is true 845/// if we're creating this built-in in anticipation of redeclaring the 846/// built-in. 847NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 848 Scope *S, bool ForRedeclaration, 849 SourceLocation Loc) { 850 Builtin::ID BID = (Builtin::ID)bid; 851 852 ASTContext::GetBuiltinTypeError Error; 853 QualType R = Context.GetBuiltinType(BID, Error); 854 switch (Error) { 855 case ASTContext::GE_None: 856 // Okay 857 break; 858 859 case ASTContext::GE_Missing_stdio: 860 if (ForRedeclaration) 861 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 862 << Context.BuiltinInfo.GetName(BID); 863 return 0; 864 865 case ASTContext::GE_Missing_setjmp: 866 if (ForRedeclaration) 867 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 868 << Context.BuiltinInfo.GetName(BID); 869 return 0; 870 } 871 872 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 873 Diag(Loc, diag::ext_implicit_lib_function_decl) 874 << Context.BuiltinInfo.GetName(BID) 875 << R; 876 if (Context.BuiltinInfo.getHeaderName(BID) && 877 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 878 != Diagnostic::Ignored) 879 Diag(Loc, diag::note_please_include_header) 880 << Context.BuiltinInfo.getHeaderName(BID) 881 << Context.BuiltinInfo.GetName(BID); 882 } 883 884 FunctionDecl *New = FunctionDecl::Create(Context, 885 Context.getTranslationUnitDecl(), 886 Loc, Loc, II, R, /*TInfo=*/0, 887 SC_Extern, 888 SC_None, false, 889 /*hasPrototype=*/true); 890 New->setImplicit(); 891 892 // Create Decl objects for each parameter, adding them to the 893 // FunctionDecl. 894 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 895 llvm::SmallVector<ParmVarDecl*, 16> Params; 896 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 897 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 898 SourceLocation(), 0, 899 FT->getArgType(i), /*TInfo=*/0, 900 SC_None, SC_None, 0)); 901 New->setParams(Params.data(), Params.size()); 902 } 903 904 AddKnownFunctionAttributes(New); 905 906 // TUScope is the translation-unit scope to insert this function into. 907 // FIXME: This is hideous. We need to teach PushOnScopeChains to 908 // relate Scopes to DeclContexts, and probably eliminate CurContext 909 // entirely, but we're not there yet. 910 DeclContext *SavedContext = CurContext; 911 CurContext = Context.getTranslationUnitDecl(); 912 PushOnScopeChains(New, TUScope); 913 CurContext = SavedContext; 914 return New; 915} 916 917/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 918/// same name and scope as a previous declaration 'Old'. Figure out 919/// how to resolve this situation, merging decls or emitting 920/// diagnostics as appropriate. If there was an error, set New to be invalid. 921/// 922void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 923 // If the new decl is known invalid already, don't bother doing any 924 // merging checks. 925 if (New->isInvalidDecl()) return; 926 927 // Allow multiple definitions for ObjC built-in typedefs. 928 // FIXME: Verify the underlying types are equivalent! 929 if (getLangOptions().ObjC1) { 930 const IdentifierInfo *TypeID = New->getIdentifier(); 931 switch (TypeID->getLength()) { 932 default: break; 933 case 2: 934 if (!TypeID->isStr("id")) 935 break; 936 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 937 // Install the built-in type for 'id', ignoring the current definition. 938 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 939 return; 940 case 5: 941 if (!TypeID->isStr("Class")) 942 break; 943 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 944 // Install the built-in type for 'Class', ignoring the current definition. 945 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 946 return; 947 case 3: 948 if (!TypeID->isStr("SEL")) 949 break; 950 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 951 // Install the built-in type for 'SEL', ignoring the current definition. 952 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 953 return; 954 case 8: 955 if (!TypeID->isStr("Protocol")) 956 break; 957 Context.setObjCProtoType(New->getUnderlyingType()); 958 return; 959 } 960 // Fall through - the typedef name was not a builtin type. 961 } 962 963 // Verify the old decl was also a type. 964 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 965 if (!Old) { 966 Diag(New->getLocation(), diag::err_redefinition_different_kind) 967 << New->getDeclName(); 968 969 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 970 if (OldD->getLocation().isValid()) 971 Diag(OldD->getLocation(), diag::note_previous_definition); 972 973 return New->setInvalidDecl(); 974 } 975 976 // If the old declaration is invalid, just give up here. 977 if (Old->isInvalidDecl()) 978 return New->setInvalidDecl(); 979 980 // Determine the "old" type we'll use for checking and diagnostics. 981 QualType OldType; 982 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 983 OldType = OldTypedef->getUnderlyingType(); 984 else 985 OldType = Context.getTypeDeclType(Old); 986 987 // If the typedef types are not identical, reject them in all languages and 988 // with any extensions enabled. 989 990 if (OldType != New->getUnderlyingType() && 991 Context.getCanonicalType(OldType) != 992 Context.getCanonicalType(New->getUnderlyingType())) { 993 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 994 << New->getUnderlyingType() << OldType; 995 if (Old->getLocation().isValid()) 996 Diag(Old->getLocation(), diag::note_previous_definition); 997 return New->setInvalidDecl(); 998 } 999 1000 // The types match. Link up the redeclaration chain if the old 1001 // declaration was a typedef. 1002 // FIXME: this is a potential source of wierdness if the type 1003 // spellings don't match exactly. 1004 if (isa<TypedefDecl>(Old)) 1005 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 1006 1007 if (getLangOptions().Microsoft) 1008 return; 1009 1010 if (getLangOptions().CPlusPlus) { 1011 // C++ [dcl.typedef]p2: 1012 // In a given non-class scope, a typedef specifier can be used to 1013 // redefine the name of any type declared in that scope to refer 1014 // to the type to which it already refers. 1015 if (!isa<CXXRecordDecl>(CurContext)) 1016 return; 1017 1018 // C++0x [dcl.typedef]p4: 1019 // In a given class scope, a typedef specifier can be used to redefine 1020 // any class-name declared in that scope that is not also a typedef-name 1021 // to refer to the type to which it already refers. 1022 // 1023 // This wording came in via DR424, which was a correction to the 1024 // wording in DR56, which accidentally banned code like: 1025 // 1026 // struct S { 1027 // typedef struct A { } A; 1028 // }; 1029 // 1030 // in the C++03 standard. We implement the C++0x semantics, which 1031 // allow the above but disallow 1032 // 1033 // struct S { 1034 // typedef int I; 1035 // typedef int I; 1036 // }; 1037 // 1038 // since that was the intent of DR56. 1039 if (!isa<TypedefDecl >(Old)) 1040 return; 1041 1042 Diag(New->getLocation(), diag::err_redefinition) 1043 << New->getDeclName(); 1044 Diag(Old->getLocation(), diag::note_previous_definition); 1045 return New->setInvalidDecl(); 1046 } 1047 1048 // If we have a redefinition of a typedef in C, emit a warning. This warning 1049 // is normally mapped to an error, but can be controlled with 1050 // -Wtypedef-redefinition. If either the original or the redefinition is 1051 // in a system header, don't emit this for compatibility with GCC. 1052 if (getDiagnostics().getSuppressSystemWarnings() && 1053 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1054 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1055 return; 1056 1057 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1058 << New->getDeclName(); 1059 Diag(Old->getLocation(), diag::note_previous_definition); 1060 return; 1061} 1062 1063/// DeclhasAttr - returns true if decl Declaration already has the target 1064/// attribute. 1065static bool 1066DeclHasAttr(const Decl *D, const Attr *A) { 1067 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1068 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1069 if ((*i)->getKind() == A->getKind()) { 1070 // FIXME: Don't hardcode this check 1071 if (OA && isa<OwnershipAttr>(*i)) 1072 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1073 return true; 1074 } 1075 1076 return false; 1077} 1078 1079/// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 1080static void mergeDeclAttributes(Decl *newDecl, const Decl *oldDecl, 1081 ASTContext &C) { 1082 if (!oldDecl->hasAttrs()) 1083 return; 1084 1085 bool foundAny = newDecl->hasAttrs(); 1086 1087 // Ensure that any moving of objects within the allocated map is done before 1088 // we process them. 1089 if (!foundAny) newDecl->setAttrs(AttrVec()); 1090 1091 for (specific_attr_iterator<InheritableAttr> 1092 i = oldDecl->specific_attr_begin<InheritableAttr>(), 1093 e = oldDecl->specific_attr_end<InheritableAttr>(); i != e; ++i) { 1094 if (!DeclHasAttr(newDecl, *i)) { 1095 InheritableAttr *newAttr = cast<InheritableAttr>((*i)->clone(C)); 1096 newAttr->setInherited(true); 1097 newDecl->addAttr(newAttr); 1098 foundAny = true; 1099 } 1100 } 1101 1102 if (!foundAny) newDecl->dropAttrs(); 1103} 1104 1105/// mergeParamDeclAttributes - Copy attributes from the old parameter 1106/// to the new one. 1107static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 1108 const ParmVarDecl *oldDecl, 1109 ASTContext &C) { 1110 if (!oldDecl->hasAttrs()) 1111 return; 1112 1113 bool foundAny = newDecl->hasAttrs(); 1114 1115 // Ensure that any moving of objects within the allocated map is 1116 // done before we process them. 1117 if (!foundAny) newDecl->setAttrs(AttrVec()); 1118 1119 for (specific_attr_iterator<InheritableParamAttr> 1120 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 1121 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 1122 if (!DeclHasAttr(newDecl, *i)) { 1123 InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(C)); 1124 newAttr->setInherited(true); 1125 newDecl->addAttr(newAttr); 1126 foundAny = true; 1127 } 1128 } 1129 1130 if (!foundAny) newDecl->dropAttrs(); 1131} 1132 1133namespace { 1134 1135/// Used in MergeFunctionDecl to keep track of function parameters in 1136/// C. 1137struct GNUCompatibleParamWarning { 1138 ParmVarDecl *OldParm; 1139 ParmVarDecl *NewParm; 1140 QualType PromotedType; 1141}; 1142 1143} 1144 1145/// getSpecialMember - get the special member enum for a method. 1146Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1147 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1148 if (Ctor->isCopyConstructor()) 1149 return Sema::CXXCopyConstructor; 1150 1151 return Sema::CXXConstructor; 1152 } 1153 1154 if (isa<CXXDestructorDecl>(MD)) 1155 return Sema::CXXDestructor; 1156 1157 assert(MD->isCopyAssignmentOperator() && 1158 "Must have copy assignment operator"); 1159 return Sema::CXXCopyAssignment; 1160} 1161 1162/// canRedefineFunction - checks if a function can be redefined. Currently, 1163/// only extern inline functions can be redefined, and even then only in 1164/// GNU89 mode. 1165static bool canRedefineFunction(const FunctionDecl *FD, 1166 const LangOptions& LangOpts) { 1167 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1168 FD->isInlineSpecified() && 1169 FD->getStorageClass() == SC_Extern); 1170} 1171 1172/// MergeFunctionDecl - We just parsed a function 'New' from 1173/// declarator D which has the same name and scope as a previous 1174/// declaration 'Old'. Figure out how to resolve this situation, 1175/// merging decls or emitting diagnostics as appropriate. 1176/// 1177/// In C++, New and Old must be declarations that are not 1178/// overloaded. Use IsOverload to determine whether New and Old are 1179/// overloaded, and to select the Old declaration that New should be 1180/// merged with. 1181/// 1182/// Returns true if there was an error, false otherwise. 1183bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1184 // Verify the old decl was also a function. 1185 FunctionDecl *Old = 0; 1186 if (FunctionTemplateDecl *OldFunctionTemplate 1187 = dyn_cast<FunctionTemplateDecl>(OldD)) 1188 Old = OldFunctionTemplate->getTemplatedDecl(); 1189 else 1190 Old = dyn_cast<FunctionDecl>(OldD); 1191 if (!Old) { 1192 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1193 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1194 Diag(Shadow->getTargetDecl()->getLocation(), 1195 diag::note_using_decl_target); 1196 Diag(Shadow->getUsingDecl()->getLocation(), 1197 diag::note_using_decl) << 0; 1198 return true; 1199 } 1200 1201 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1202 << New->getDeclName(); 1203 Diag(OldD->getLocation(), diag::note_previous_definition); 1204 return true; 1205 } 1206 1207 // Determine whether the previous declaration was a definition, 1208 // implicit declaration, or a declaration. 1209 diag::kind PrevDiag; 1210 if (Old->isThisDeclarationADefinition()) 1211 PrevDiag = diag::note_previous_definition; 1212 else if (Old->isImplicit()) 1213 PrevDiag = diag::note_previous_implicit_declaration; 1214 else 1215 PrevDiag = diag::note_previous_declaration; 1216 1217 QualType OldQType = Context.getCanonicalType(Old->getType()); 1218 QualType NewQType = Context.getCanonicalType(New->getType()); 1219 1220 // Don't complain about this if we're in GNU89 mode and the old function 1221 // is an extern inline function. 1222 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1223 New->getStorageClass() == SC_Static && 1224 Old->getStorageClass() != SC_Static && 1225 !canRedefineFunction(Old, getLangOptions())) { 1226 Diag(New->getLocation(), diag::err_static_non_static) 1227 << New; 1228 Diag(Old->getLocation(), PrevDiag); 1229 return true; 1230 } 1231 1232 // If a function is first declared with a calling convention, but is 1233 // later declared or defined without one, the second decl assumes the 1234 // calling convention of the first. 1235 // 1236 // For the new decl, we have to look at the NON-canonical type to tell the 1237 // difference between a function that really doesn't have a calling 1238 // convention and one that is declared cdecl. That's because in 1239 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1240 // because it is the default calling convention. 1241 // 1242 // Note also that we DO NOT return at this point, because we still have 1243 // other tests to run. 1244 const FunctionType *OldType = cast<FunctionType>(OldQType); 1245 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1246 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1247 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1248 bool RequiresAdjustment = false; 1249 if (OldTypeInfo.getCC() != CC_Default && 1250 NewTypeInfo.getCC() == CC_Default) { 1251 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1252 RequiresAdjustment = true; 1253 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1254 NewTypeInfo.getCC())) { 1255 // Calling conventions really aren't compatible, so complain. 1256 Diag(New->getLocation(), diag::err_cconv_change) 1257 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1258 << (OldTypeInfo.getCC() == CC_Default) 1259 << (OldTypeInfo.getCC() == CC_Default ? "" : 1260 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1261 Diag(Old->getLocation(), diag::note_previous_declaration); 1262 return true; 1263 } 1264 1265 // FIXME: diagnose the other way around? 1266 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1267 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1268 RequiresAdjustment = true; 1269 } 1270 1271 // Merge regparm attribute. 1272 if (OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1273 if (NewTypeInfo.getRegParm()) { 1274 Diag(New->getLocation(), diag::err_regparm_mismatch) 1275 << NewType->getRegParmType() 1276 << OldType->getRegParmType(); 1277 Diag(Old->getLocation(), diag::note_previous_declaration); 1278 return true; 1279 } 1280 1281 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1282 RequiresAdjustment = true; 1283 } 1284 1285 if (RequiresAdjustment) { 1286 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1287 New->setType(QualType(NewType, 0)); 1288 NewQType = Context.getCanonicalType(New->getType()); 1289 } 1290 1291 if (getLangOptions().CPlusPlus) { 1292 // (C++98 13.1p2): 1293 // Certain function declarations cannot be overloaded: 1294 // -- Function declarations that differ only in the return type 1295 // cannot be overloaded. 1296 QualType OldReturnType = OldType->getResultType(); 1297 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1298 QualType ResQT; 1299 if (OldReturnType != NewReturnType) { 1300 if (NewReturnType->isObjCObjectPointerType() 1301 && OldReturnType->isObjCObjectPointerType()) 1302 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1303 if (ResQT.isNull()) { 1304 if (New->isCXXClassMember() && New->isOutOfLine()) 1305 Diag(New->getLocation(), 1306 diag::err_member_def_does_not_match_ret_type) << New; 1307 else 1308 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1309 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1310 return true; 1311 } 1312 else 1313 NewQType = ResQT; 1314 } 1315 1316 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1317 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1318 if (OldMethod && NewMethod) { 1319 // Preserve triviality. 1320 NewMethod->setTrivial(OldMethod->isTrivial()); 1321 1322 bool isFriend = NewMethod->getFriendObjectKind(); 1323 1324 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1325 // -- Member function declarations with the same name and the 1326 // same parameter types cannot be overloaded if any of them 1327 // is a static member function declaration. 1328 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1329 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1330 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1331 return true; 1332 } 1333 1334 // C++ [class.mem]p1: 1335 // [...] A member shall not be declared twice in the 1336 // member-specification, except that a nested class or member 1337 // class template can be declared and then later defined. 1338 unsigned NewDiag; 1339 if (isa<CXXConstructorDecl>(OldMethod)) 1340 NewDiag = diag::err_constructor_redeclared; 1341 else if (isa<CXXDestructorDecl>(NewMethod)) 1342 NewDiag = diag::err_destructor_redeclared; 1343 else if (isa<CXXConversionDecl>(NewMethod)) 1344 NewDiag = diag::err_conv_function_redeclared; 1345 else 1346 NewDiag = diag::err_member_redeclared; 1347 1348 Diag(New->getLocation(), NewDiag); 1349 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1350 1351 // Complain if this is an explicit declaration of a special 1352 // member that was initially declared implicitly. 1353 // 1354 // As an exception, it's okay to befriend such methods in order 1355 // to permit the implicit constructor/destructor/operator calls. 1356 } else if (OldMethod->isImplicit()) { 1357 if (isFriend) { 1358 NewMethod->setImplicit(); 1359 } else { 1360 Diag(NewMethod->getLocation(), 1361 diag::err_definition_of_implicitly_declared_member) 1362 << New << getSpecialMember(OldMethod); 1363 return true; 1364 } 1365 } 1366 } 1367 1368 // (C++98 8.3.5p3): 1369 // All declarations for a function shall agree exactly in both the 1370 // return type and the parameter-type-list. 1371 // We also want to respect all the extended bits except noreturn. 1372 1373 // noreturn should now match unless the old type info didn't have it. 1374 QualType OldQTypeForComparison = OldQType; 1375 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1376 assert(OldQType == QualType(OldType, 0)); 1377 const FunctionType *OldTypeForComparison 1378 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1379 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1380 assert(OldQTypeForComparison.isCanonical()); 1381 } 1382 1383 if (OldQTypeForComparison == NewQType) 1384 return MergeCompatibleFunctionDecls(New, Old); 1385 1386 // Fall through for conflicting redeclarations and redefinitions. 1387 } 1388 1389 // C: Function types need to be compatible, not identical. This handles 1390 // duplicate function decls like "void f(int); void f(enum X);" properly. 1391 if (!getLangOptions().CPlusPlus && 1392 Context.typesAreCompatible(OldQType, NewQType)) { 1393 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1394 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1395 const FunctionProtoType *OldProto = 0; 1396 if (isa<FunctionNoProtoType>(NewFuncType) && 1397 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1398 // The old declaration provided a function prototype, but the 1399 // new declaration does not. Merge in the prototype. 1400 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1401 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1402 OldProto->arg_type_end()); 1403 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1404 ParamTypes.data(), ParamTypes.size(), 1405 OldProto->getExtProtoInfo()); 1406 New->setType(NewQType); 1407 New->setHasInheritedPrototype(); 1408 1409 // Synthesize a parameter for each argument type. 1410 llvm::SmallVector<ParmVarDecl*, 16> Params; 1411 for (FunctionProtoType::arg_type_iterator 1412 ParamType = OldProto->arg_type_begin(), 1413 ParamEnd = OldProto->arg_type_end(); 1414 ParamType != ParamEnd; ++ParamType) { 1415 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1416 SourceLocation(), 1417 SourceLocation(), 0, 1418 *ParamType, /*TInfo=*/0, 1419 SC_None, SC_None, 1420 0); 1421 Param->setImplicit(); 1422 Params.push_back(Param); 1423 } 1424 1425 New->setParams(Params.data(), Params.size()); 1426 } 1427 1428 return MergeCompatibleFunctionDecls(New, Old); 1429 } 1430 1431 // GNU C permits a K&R definition to follow a prototype declaration 1432 // if the declared types of the parameters in the K&R definition 1433 // match the types in the prototype declaration, even when the 1434 // promoted types of the parameters from the K&R definition differ 1435 // from the types in the prototype. GCC then keeps the types from 1436 // the prototype. 1437 // 1438 // If a variadic prototype is followed by a non-variadic K&R definition, 1439 // the K&R definition becomes variadic. This is sort of an edge case, but 1440 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1441 // C99 6.9.1p8. 1442 if (!getLangOptions().CPlusPlus && 1443 Old->hasPrototype() && !New->hasPrototype() && 1444 New->getType()->getAs<FunctionProtoType>() && 1445 Old->getNumParams() == New->getNumParams()) { 1446 llvm::SmallVector<QualType, 16> ArgTypes; 1447 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1448 const FunctionProtoType *OldProto 1449 = Old->getType()->getAs<FunctionProtoType>(); 1450 const FunctionProtoType *NewProto 1451 = New->getType()->getAs<FunctionProtoType>(); 1452 1453 // Determine whether this is the GNU C extension. 1454 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1455 NewProto->getResultType()); 1456 bool LooseCompatible = !MergedReturn.isNull(); 1457 for (unsigned Idx = 0, End = Old->getNumParams(); 1458 LooseCompatible && Idx != End; ++Idx) { 1459 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1460 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1461 if (Context.typesAreCompatible(OldParm->getType(), 1462 NewProto->getArgType(Idx))) { 1463 ArgTypes.push_back(NewParm->getType()); 1464 } else if (Context.typesAreCompatible(OldParm->getType(), 1465 NewParm->getType(), 1466 /*CompareUnqualified=*/true)) { 1467 GNUCompatibleParamWarning Warn 1468 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1469 Warnings.push_back(Warn); 1470 ArgTypes.push_back(NewParm->getType()); 1471 } else 1472 LooseCompatible = false; 1473 } 1474 1475 if (LooseCompatible) { 1476 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1477 Diag(Warnings[Warn].NewParm->getLocation(), 1478 diag::ext_param_promoted_not_compatible_with_prototype) 1479 << Warnings[Warn].PromotedType 1480 << Warnings[Warn].OldParm->getType(); 1481 if (Warnings[Warn].OldParm->getLocation().isValid()) 1482 Diag(Warnings[Warn].OldParm->getLocation(), 1483 diag::note_previous_declaration); 1484 } 1485 1486 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1487 ArgTypes.size(), 1488 OldProto->getExtProtoInfo())); 1489 return MergeCompatibleFunctionDecls(New, Old); 1490 } 1491 1492 // Fall through to diagnose conflicting types. 1493 } 1494 1495 // A function that has already been declared has been redeclared or defined 1496 // with a different type- show appropriate diagnostic 1497 if (unsigned BuiltinID = Old->getBuiltinID()) { 1498 // The user has declared a builtin function with an incompatible 1499 // signature. 1500 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1501 // The function the user is redeclaring is a library-defined 1502 // function like 'malloc' or 'printf'. Warn about the 1503 // redeclaration, then pretend that we don't know about this 1504 // library built-in. 1505 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1506 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1507 << Old << Old->getType(); 1508 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1509 Old->setInvalidDecl(); 1510 return false; 1511 } 1512 1513 PrevDiag = diag::note_previous_builtin_declaration; 1514 } 1515 1516 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1517 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1518 return true; 1519} 1520 1521/// \brief Completes the merge of two function declarations that are 1522/// known to be compatible. 1523/// 1524/// This routine handles the merging of attributes and other 1525/// properties of function declarations form the old declaration to 1526/// the new declaration, once we know that New is in fact a 1527/// redeclaration of Old. 1528/// 1529/// \returns false 1530bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1531 // Merge the attributes 1532 mergeDeclAttributes(New, Old, Context); 1533 1534 // Merge the storage class. 1535 if (Old->getStorageClass() != SC_Extern && 1536 Old->getStorageClass() != SC_None) 1537 New->setStorageClass(Old->getStorageClass()); 1538 1539 // Merge "pure" flag. 1540 if (Old->isPure()) 1541 New->setPure(); 1542 1543 // Merge the "deleted" flag. 1544 if (Old->isDeleted()) 1545 New->setDeleted(); 1546 1547 // Merge attributes from the parameters. These can mismatch with K&R 1548 // declarations. 1549 if (New->getNumParams() == Old->getNumParams()) 1550 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1551 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1552 Context); 1553 1554 if (getLangOptions().CPlusPlus) 1555 return MergeCXXFunctionDecl(New, Old); 1556 1557 return false; 1558} 1559 1560void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1561 const ObjCMethodDecl *oldMethod) { 1562 // Merge the attributes. 1563 mergeDeclAttributes(newMethod, oldMethod, Context); 1564 1565 // Merge attributes from the parameters. 1566 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1567 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1568 ni != ne; ++ni, ++oi) 1569 mergeParamDeclAttributes(*ni, *oi, Context); 1570} 1571 1572/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 1573/// scope as a previous declaration 'Old'. Figure out how to merge their types, 1574/// emitting diagnostics as appropriate. 1575/// 1576/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1577/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1578/// check them before the initializer is attached. 1579/// 1580void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1581 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1582 return; 1583 1584 QualType MergedT; 1585 if (getLangOptions().CPlusPlus) { 1586 AutoType *AT = New->getType()->getContainedAutoType(); 1587 if (AT && !AT->isDeduced()) { 1588 // We don't know what the new type is until the initializer is attached. 1589 return; 1590 } else if (Context.hasSameType(New->getType(), Old->getType())) { 1591 // These could still be something that needs exception specs checked. 1592 return MergeVarDeclExceptionSpecs(New, Old); 1593 } 1594 // C++ [basic.link]p10: 1595 // [...] the types specified by all declarations referring to a given 1596 // object or function shall be identical, except that declarations for an 1597 // array object can specify array types that differ by the presence or 1598 // absence of a major array bound (8.3.4). 1599 else if (Old->getType()->isIncompleteArrayType() && 1600 New->getType()->isArrayType()) { 1601 CanQual<ArrayType> OldArray 1602 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1603 CanQual<ArrayType> NewArray 1604 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1605 if (OldArray->getElementType() == NewArray->getElementType()) 1606 MergedT = New->getType(); 1607 } else if (Old->getType()->isArrayType() && 1608 New->getType()->isIncompleteArrayType()) { 1609 CanQual<ArrayType> OldArray 1610 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1611 CanQual<ArrayType> NewArray 1612 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1613 if (OldArray->getElementType() == NewArray->getElementType()) 1614 MergedT = Old->getType(); 1615 } else if (New->getType()->isObjCObjectPointerType() 1616 && Old->getType()->isObjCObjectPointerType()) { 1617 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1618 Old->getType()); 1619 } 1620 } else { 1621 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1622 } 1623 if (MergedT.isNull()) { 1624 Diag(New->getLocation(), diag::err_redefinition_different_type) 1625 << New->getDeclName(); 1626 Diag(Old->getLocation(), diag::note_previous_definition); 1627 return New->setInvalidDecl(); 1628 } 1629 New->setType(MergedT); 1630} 1631 1632/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1633/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1634/// situation, merging decls or emitting diagnostics as appropriate. 1635/// 1636/// Tentative definition rules (C99 6.9.2p2) are checked by 1637/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1638/// definitions here, since the initializer hasn't been attached. 1639/// 1640void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1641 // If the new decl is already invalid, don't do any other checking. 1642 if (New->isInvalidDecl()) 1643 return; 1644 1645 // Verify the old decl was also a variable. 1646 VarDecl *Old = 0; 1647 if (!Previous.isSingleResult() || 1648 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1649 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1650 << New->getDeclName(); 1651 Diag(Previous.getRepresentativeDecl()->getLocation(), 1652 diag::note_previous_definition); 1653 return New->setInvalidDecl(); 1654 } 1655 1656 // C++ [class.mem]p1: 1657 // A member shall not be declared twice in the member-specification [...] 1658 // 1659 // Here, we need only consider static data members. 1660 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1661 Diag(New->getLocation(), diag::err_duplicate_member) 1662 << New->getIdentifier(); 1663 Diag(Old->getLocation(), diag::note_previous_declaration); 1664 New->setInvalidDecl(); 1665 } 1666 1667 mergeDeclAttributes(New, Old, Context); 1668 1669 // Merge the types. 1670 MergeVarDeclTypes(New, Old); 1671 if (New->isInvalidDecl()) 1672 return; 1673 1674 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1675 if (New->getStorageClass() == SC_Static && 1676 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1677 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1678 Diag(Old->getLocation(), diag::note_previous_definition); 1679 return New->setInvalidDecl(); 1680 } 1681 // C99 6.2.2p4: 1682 // For an identifier declared with the storage-class specifier 1683 // extern in a scope in which a prior declaration of that 1684 // identifier is visible,23) if the prior declaration specifies 1685 // internal or external linkage, the linkage of the identifier at 1686 // the later declaration is the same as the linkage specified at 1687 // the prior declaration. If no prior declaration is visible, or 1688 // if the prior declaration specifies no linkage, then the 1689 // identifier has external linkage. 1690 if (New->hasExternalStorage() && Old->hasLinkage()) 1691 /* Okay */; 1692 else if (New->getStorageClass() != SC_Static && 1693 Old->getStorageClass() == SC_Static) { 1694 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1695 Diag(Old->getLocation(), diag::note_previous_definition); 1696 return New->setInvalidDecl(); 1697 } 1698 1699 // Check if extern is followed by non-extern and vice-versa. 1700 if (New->hasExternalStorage() && 1701 !Old->hasLinkage() && Old->isLocalVarDecl()) { 1702 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 1703 Diag(Old->getLocation(), diag::note_previous_definition); 1704 return New->setInvalidDecl(); 1705 } 1706 if (Old->hasExternalStorage() && 1707 !New->hasLinkage() && New->isLocalVarDecl()) { 1708 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 1709 Diag(Old->getLocation(), diag::note_previous_definition); 1710 return New->setInvalidDecl(); 1711 } 1712 1713 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1714 1715 // FIXME: The test for external storage here seems wrong? We still 1716 // need to check for mismatches. 1717 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1718 // Don't complain about out-of-line definitions of static members. 1719 !(Old->getLexicalDeclContext()->isRecord() && 1720 !New->getLexicalDeclContext()->isRecord())) { 1721 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1722 Diag(Old->getLocation(), diag::note_previous_definition); 1723 return New->setInvalidDecl(); 1724 } 1725 1726 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1727 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1728 Diag(Old->getLocation(), diag::note_previous_definition); 1729 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1730 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1731 Diag(Old->getLocation(), diag::note_previous_definition); 1732 } 1733 1734 // C++ doesn't have tentative definitions, so go right ahead and check here. 1735 const VarDecl *Def; 1736 if (getLangOptions().CPlusPlus && 1737 New->isThisDeclarationADefinition() == VarDecl::Definition && 1738 (Def = Old->getDefinition())) { 1739 Diag(New->getLocation(), diag::err_redefinition) 1740 << New->getDeclName(); 1741 Diag(Def->getLocation(), diag::note_previous_definition); 1742 New->setInvalidDecl(); 1743 return; 1744 } 1745 // c99 6.2.2 P4. 1746 // For an identifier declared with the storage-class specifier extern in a 1747 // scope in which a prior declaration of that identifier is visible, if 1748 // the prior declaration specifies internal or external linkage, the linkage 1749 // of the identifier at the later declaration is the same as the linkage 1750 // specified at the prior declaration. 1751 // FIXME. revisit this code. 1752 if (New->hasExternalStorage() && 1753 Old->getLinkage() == InternalLinkage && 1754 New->getDeclContext() == Old->getDeclContext()) 1755 New->setStorageClass(Old->getStorageClass()); 1756 1757 // Keep a chain of previous declarations. 1758 New->setPreviousDeclaration(Old); 1759 1760 // Inherit access appropriately. 1761 New->setAccess(Old->getAccess()); 1762} 1763 1764/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1765/// no declarator (e.g. "struct foo;") is parsed. 1766Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1767 DeclSpec &DS) { 1768 Decl *TagD = 0; 1769 TagDecl *Tag = 0; 1770 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1771 DS.getTypeSpecType() == DeclSpec::TST_struct || 1772 DS.getTypeSpecType() == DeclSpec::TST_union || 1773 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1774 TagD = DS.getRepAsDecl(); 1775 1776 if (!TagD) // We probably had an error 1777 return 0; 1778 1779 // Note that the above type specs guarantee that the 1780 // type rep is a Decl, whereas in many of the others 1781 // it's a Type. 1782 Tag = dyn_cast<TagDecl>(TagD); 1783 } 1784 1785 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1786 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1787 // or incomplete types shall not be restrict-qualified." 1788 if (TypeQuals & DeclSpec::TQ_restrict) 1789 Diag(DS.getRestrictSpecLoc(), 1790 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1791 << DS.getSourceRange(); 1792 } 1793 1794 if (DS.isFriendSpecified()) { 1795 // If we're dealing with a decl but not a TagDecl, assume that 1796 // whatever routines created it handled the friendship aspect. 1797 if (TagD && !Tag) 1798 return 0; 1799 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1800 } 1801 1802 // Track whether we warned about the fact that there aren't any 1803 // declarators. 1804 bool emittedWarning = false; 1805 1806 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1807 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 1808 1809 if (!Record->getDeclName() && Record->isDefinition() && 1810 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1811 if (getLangOptions().CPlusPlus || 1812 Record->getDeclContext()->isRecord()) 1813 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1814 1815 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1816 << DS.getSourceRange(); 1817 emittedWarning = true; 1818 } 1819 } 1820 1821 // Check for Microsoft C extension: anonymous struct. 1822 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 1823 CurContext->isRecord() && 1824 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 1825 // Handle 2 kinds of anonymous struct: 1826 // struct STRUCT; 1827 // and 1828 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 1829 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 1830 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 1831 (DS.getTypeSpecType() == DeclSpec::TST_typename && 1832 DS.getRepAsType().get()->isStructureType())) { 1833 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 1834 << DS.getSourceRange(); 1835 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 1836 } 1837 } 1838 1839 if (getLangOptions().CPlusPlus && 1840 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1841 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1842 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1843 !Enum->getIdentifier() && !Enum->isInvalidDecl()) { 1844 Diag(Enum->getLocation(), diag::ext_no_declarators) 1845 << DS.getSourceRange(); 1846 emittedWarning = true; 1847 } 1848 1849 // Skip all the checks below if we have a type error. 1850 if (DS.getTypeSpecType() == DeclSpec::TST_error) return TagD; 1851 1852 if (!DS.isMissingDeclaratorOk()) { 1853 // Warn about typedefs of enums without names, since this is an 1854 // extension in both Microsoft and GNU. 1855 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1856 Tag && isa<EnumDecl>(Tag)) { 1857 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1858 << DS.getSourceRange(); 1859 return Tag; 1860 } 1861 1862 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1863 << DS.getSourceRange(); 1864 emittedWarning = true; 1865 } 1866 1867 // We're going to complain about a bunch of spurious specifiers; 1868 // only do this if we're declaring a tag, because otherwise we 1869 // should be getting diag::ext_no_declarators. 1870 if (emittedWarning || (TagD && TagD->isInvalidDecl())) 1871 return TagD; 1872 1873 if (DeclSpec::SCS scs = DS.getStorageClassSpec()) 1874 Diag(DS.getStorageClassSpecLoc(), diag::warn_standalone_specifier) 1875 << DeclSpec::getSpecifierName(scs); 1876 if (DS.isThreadSpecified()) 1877 Diag(DS.getThreadSpecLoc(), diag::warn_standalone_specifier) << "__thread"; 1878 if (DS.getTypeQualifiers()) { 1879 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 1880 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "const"; 1881 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 1882 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "volatile"; 1883 // Restrict is covered above. 1884 } 1885 if (DS.isInlineSpecified()) 1886 Diag(DS.getInlineSpecLoc(), diag::warn_standalone_specifier) << "inline"; 1887 if (DS.isVirtualSpecified()) 1888 Diag(DS.getVirtualSpecLoc(), diag::warn_standalone_specifier) << "virtual"; 1889 if (DS.isExplicitSpecified()) 1890 Diag(DS.getExplicitSpecLoc(), diag::warn_standalone_specifier) <<"explicit"; 1891 1892 // FIXME: Warn on useless attributes 1893 1894 return TagD; 1895} 1896 1897/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1898/// builds a statement for it and returns it so it is evaluated. 1899StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1900 StmtResult R; 1901 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1902 Expr *Exp = DS.getRepAsExpr(); 1903 QualType Ty = Exp->getType(); 1904 if (Ty->isPointerType()) { 1905 do 1906 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1907 while (Ty->isPointerType()); 1908 } 1909 if (Ty->isVariableArrayType()) { 1910 R = ActOnExprStmt(MakeFullExpr(Exp)); 1911 } 1912 } 1913 return R; 1914} 1915 1916/// We are trying to inject an anonymous member into the given scope; 1917/// check if there's an existing declaration that can't be overloaded. 1918/// 1919/// \return true if this is a forbidden redeclaration 1920static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1921 Scope *S, 1922 DeclContext *Owner, 1923 DeclarationName Name, 1924 SourceLocation NameLoc, 1925 unsigned diagnostic) { 1926 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1927 Sema::ForRedeclaration); 1928 if (!SemaRef.LookupName(R, S)) return false; 1929 1930 if (R.getAsSingle<TagDecl>()) 1931 return false; 1932 1933 // Pick a representative declaration. 1934 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1935 assert(PrevDecl && "Expected a non-null Decl"); 1936 1937 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1938 return false; 1939 1940 SemaRef.Diag(NameLoc, diagnostic) << Name; 1941 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1942 1943 return true; 1944} 1945 1946/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1947/// anonymous struct or union AnonRecord into the owning context Owner 1948/// and scope S. This routine will be invoked just after we realize 1949/// that an unnamed union or struct is actually an anonymous union or 1950/// struct, e.g., 1951/// 1952/// @code 1953/// union { 1954/// int i; 1955/// float f; 1956/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1957/// // f into the surrounding scope.x 1958/// @endcode 1959/// 1960/// This routine is recursive, injecting the names of nested anonymous 1961/// structs/unions into the owning context and scope as well. 1962static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1963 DeclContext *Owner, 1964 RecordDecl *AnonRecord, 1965 AccessSpecifier AS, 1966 llvm::SmallVector<NamedDecl*, 2> &Chaining, 1967 bool MSAnonStruct) { 1968 unsigned diagKind 1969 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1970 : diag::err_anonymous_struct_member_redecl; 1971 1972 bool Invalid = false; 1973 1974 // Look every FieldDecl and IndirectFieldDecl with a name. 1975 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 1976 DEnd = AnonRecord->decls_end(); 1977 D != DEnd; ++D) { 1978 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 1979 cast<NamedDecl>(*D)->getDeclName()) { 1980 ValueDecl *VD = cast<ValueDecl>(*D); 1981 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 1982 VD->getLocation(), diagKind)) { 1983 // C++ [class.union]p2: 1984 // The names of the members of an anonymous union shall be 1985 // distinct from the names of any other entity in the 1986 // scope in which the anonymous union is declared. 1987 Invalid = true; 1988 } else { 1989 // C++ [class.union]p2: 1990 // For the purpose of name lookup, after the anonymous union 1991 // definition, the members of the anonymous union are 1992 // considered to have been defined in the scope in which the 1993 // anonymous union is declared. 1994 unsigned OldChainingSize = Chaining.size(); 1995 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 1996 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 1997 PE = IF->chain_end(); PI != PE; ++PI) 1998 Chaining.push_back(*PI); 1999 else 2000 Chaining.push_back(VD); 2001 2002 assert(Chaining.size() >= 2); 2003 NamedDecl **NamedChain = 2004 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 2005 for (unsigned i = 0; i < Chaining.size(); i++) 2006 NamedChain[i] = Chaining[i]; 2007 2008 IndirectFieldDecl* IndirectField = 2009 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 2010 VD->getIdentifier(), VD->getType(), 2011 NamedChain, Chaining.size()); 2012 2013 IndirectField->setAccess(AS); 2014 IndirectField->setImplicit(); 2015 SemaRef.PushOnScopeChains(IndirectField, S); 2016 2017 // That includes picking up the appropriate access specifier. 2018 if (AS != AS_none) IndirectField->setAccess(AS); 2019 2020 Chaining.resize(OldChainingSize); 2021 } 2022 } 2023 } 2024 2025 return Invalid; 2026} 2027 2028/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 2029/// a VarDecl::StorageClass. Any error reporting is up to the caller: 2030/// illegal input values are mapped to SC_None. 2031static StorageClass 2032StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2033 switch (StorageClassSpec) { 2034 case DeclSpec::SCS_unspecified: return SC_None; 2035 case DeclSpec::SCS_extern: return SC_Extern; 2036 case DeclSpec::SCS_static: return SC_Static; 2037 case DeclSpec::SCS_auto: return SC_Auto; 2038 case DeclSpec::SCS_register: return SC_Register; 2039 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2040 // Illegal SCSs map to None: error reporting is up to the caller. 2041 case DeclSpec::SCS_mutable: // Fall through. 2042 case DeclSpec::SCS_typedef: return SC_None; 2043 } 2044 llvm_unreachable("unknown storage class specifier"); 2045} 2046 2047/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 2048/// a StorageClass. Any error reporting is up to the caller: 2049/// illegal input values are mapped to SC_None. 2050static StorageClass 2051StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2052 switch (StorageClassSpec) { 2053 case DeclSpec::SCS_unspecified: return SC_None; 2054 case DeclSpec::SCS_extern: return SC_Extern; 2055 case DeclSpec::SCS_static: return SC_Static; 2056 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2057 // Illegal SCSs map to None: error reporting is up to the caller. 2058 case DeclSpec::SCS_auto: // Fall through. 2059 case DeclSpec::SCS_mutable: // Fall through. 2060 case DeclSpec::SCS_register: // Fall through. 2061 case DeclSpec::SCS_typedef: return SC_None; 2062 } 2063 llvm_unreachable("unknown storage class specifier"); 2064} 2065 2066/// BuildAnonymousStructOrUnion - Handle the declaration of an 2067/// anonymous structure or union. Anonymous unions are a C++ feature 2068/// (C++ [class.union]) and a GNU C extension; anonymous structures 2069/// are a GNU C and GNU C++ extension. 2070Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2071 AccessSpecifier AS, 2072 RecordDecl *Record) { 2073 DeclContext *Owner = Record->getDeclContext(); 2074 2075 // Diagnose whether this anonymous struct/union is an extension. 2076 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2077 Diag(Record->getLocation(), diag::ext_anonymous_union); 2078 else if (!Record->isUnion()) 2079 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2080 2081 // C and C++ require different kinds of checks for anonymous 2082 // structs/unions. 2083 bool Invalid = false; 2084 if (getLangOptions().CPlusPlus) { 2085 const char* PrevSpec = 0; 2086 unsigned DiagID; 2087 // C++ [class.union]p3: 2088 // Anonymous unions declared in a named namespace or in the 2089 // global namespace shall be declared static. 2090 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2091 (isa<TranslationUnitDecl>(Owner) || 2092 (isa<NamespaceDecl>(Owner) && 2093 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2094 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2095 Invalid = true; 2096 2097 // Recover by adding 'static'. 2098 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2099 PrevSpec, DiagID, getLangOptions()); 2100 } 2101 // C++ [class.union]p3: 2102 // A storage class is not allowed in a declaration of an 2103 // anonymous union in a class scope. 2104 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2105 isa<RecordDecl>(Owner)) { 2106 Diag(DS.getStorageClassSpecLoc(), 2107 diag::err_anonymous_union_with_storage_spec); 2108 Invalid = true; 2109 2110 // Recover by removing the storage specifier. 2111 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2112 PrevSpec, DiagID, getLangOptions()); 2113 } 2114 2115 // C++ [class.union]p2: 2116 // The member-specification of an anonymous union shall only 2117 // define non-static data members. [Note: nested types and 2118 // functions cannot be declared within an anonymous union. ] 2119 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2120 MemEnd = Record->decls_end(); 2121 Mem != MemEnd; ++Mem) { 2122 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2123 // C++ [class.union]p3: 2124 // An anonymous union shall not have private or protected 2125 // members (clause 11). 2126 assert(FD->getAccess() != AS_none); 2127 if (FD->getAccess() != AS_public) { 2128 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2129 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2130 Invalid = true; 2131 } 2132 2133 if (CheckNontrivialField(FD)) 2134 Invalid = true; 2135 } else if ((*Mem)->isImplicit()) { 2136 // Any implicit members are fine. 2137 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2138 // This is a type that showed up in an 2139 // elaborated-type-specifier inside the anonymous struct or 2140 // union, but which actually declares a type outside of the 2141 // anonymous struct or union. It's okay. 2142 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2143 if (!MemRecord->isAnonymousStructOrUnion() && 2144 MemRecord->getDeclName()) { 2145 // Visual C++ allows type definition in anonymous struct or union. 2146 if (getLangOptions().Microsoft) 2147 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2148 << (int)Record->isUnion(); 2149 else { 2150 // This is a nested type declaration. 2151 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2152 << (int)Record->isUnion(); 2153 Invalid = true; 2154 } 2155 } 2156 } else if (isa<AccessSpecDecl>(*Mem)) { 2157 // Any access specifier is fine. 2158 } else { 2159 // We have something that isn't a non-static data 2160 // member. Complain about it. 2161 unsigned DK = diag::err_anonymous_record_bad_member; 2162 if (isa<TypeDecl>(*Mem)) 2163 DK = diag::err_anonymous_record_with_type; 2164 else if (isa<FunctionDecl>(*Mem)) 2165 DK = diag::err_anonymous_record_with_function; 2166 else if (isa<VarDecl>(*Mem)) 2167 DK = diag::err_anonymous_record_with_static; 2168 2169 // Visual C++ allows type definition in anonymous struct or union. 2170 if (getLangOptions().Microsoft && 2171 DK == diag::err_anonymous_record_with_type) 2172 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2173 << (int)Record->isUnion(); 2174 else { 2175 Diag((*Mem)->getLocation(), DK) 2176 << (int)Record->isUnion(); 2177 Invalid = true; 2178 } 2179 } 2180 } 2181 } 2182 2183 if (!Record->isUnion() && !Owner->isRecord()) { 2184 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2185 << (int)getLangOptions().CPlusPlus; 2186 Invalid = true; 2187 } 2188 2189 // Mock up a declarator. 2190 Declarator Dc(DS, Declarator::TypeNameContext); 2191 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2192 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2193 2194 // Create a declaration for this anonymous struct/union. 2195 NamedDecl *Anon = 0; 2196 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2197 Anon = FieldDecl::Create(Context, OwningClass, 2198 DS.getSourceRange().getBegin(), 2199 Record->getLocation(), 2200 /*IdentifierInfo=*/0, 2201 Context.getTypeDeclType(Record), 2202 TInfo, 2203 /*BitWidth=*/0, /*Mutable=*/false); 2204 Anon->setAccess(AS); 2205 if (getLangOptions().CPlusPlus) 2206 FieldCollector->Add(cast<FieldDecl>(Anon)); 2207 } else { 2208 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2209 assert(SCSpec != DeclSpec::SCS_typedef && 2210 "Parser allowed 'typedef' as storage class VarDecl."); 2211 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2212 if (SCSpec == DeclSpec::SCS_mutable) { 2213 // mutable can only appear on non-static class members, so it's always 2214 // an error here 2215 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2216 Invalid = true; 2217 SC = SC_None; 2218 } 2219 SCSpec = DS.getStorageClassSpecAsWritten(); 2220 VarDecl::StorageClass SCAsWritten 2221 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2222 2223 Anon = VarDecl::Create(Context, Owner, 2224 DS.getSourceRange().getBegin(), 2225 Record->getLocation(), /*IdentifierInfo=*/0, 2226 Context.getTypeDeclType(Record), 2227 TInfo, SC, SCAsWritten); 2228 } 2229 Anon->setImplicit(); 2230 2231 // Add the anonymous struct/union object to the current 2232 // context. We'll be referencing this object when we refer to one of 2233 // its members. 2234 Owner->addDecl(Anon); 2235 2236 // Inject the members of the anonymous struct/union into the owning 2237 // context and into the identifier resolver chain for name lookup 2238 // purposes. 2239 llvm::SmallVector<NamedDecl*, 2> Chain; 2240 Chain.push_back(Anon); 2241 2242 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2243 Chain, false)) 2244 Invalid = true; 2245 2246 // Mark this as an anonymous struct/union type. Note that we do not 2247 // do this until after we have already checked and injected the 2248 // members of this anonymous struct/union type, because otherwise 2249 // the members could be injected twice: once by DeclContext when it 2250 // builds its lookup table, and once by 2251 // InjectAnonymousStructOrUnionMembers. 2252 Record->setAnonymousStructOrUnion(true); 2253 2254 if (Invalid) 2255 Anon->setInvalidDecl(); 2256 2257 return Anon; 2258} 2259 2260/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2261/// Microsoft C anonymous structure. 2262/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2263/// Example: 2264/// 2265/// struct A { int a; }; 2266/// struct B { struct A; int b; }; 2267/// 2268/// void foo() { 2269/// B var; 2270/// var.a = 3; 2271/// } 2272/// 2273Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2274 RecordDecl *Record) { 2275 2276 // If there is no Record, get the record via the typedef. 2277 if (!Record) 2278 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2279 2280 // Mock up a declarator. 2281 Declarator Dc(DS, Declarator::TypeNameContext); 2282 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2283 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2284 2285 // Create a declaration for this anonymous struct. 2286 NamedDecl* Anon = FieldDecl::Create(Context, 2287 cast<RecordDecl>(CurContext), 2288 DS.getSourceRange().getBegin(), 2289 DS.getSourceRange().getBegin(), 2290 /*IdentifierInfo=*/0, 2291 Context.getTypeDeclType(Record), 2292 TInfo, 2293 /*BitWidth=*/0, /*Mutable=*/false); 2294 Anon->setImplicit(); 2295 2296 // Add the anonymous struct object to the current context. 2297 CurContext->addDecl(Anon); 2298 2299 // Inject the members of the anonymous struct into the current 2300 // context and into the identifier resolver chain for name lookup 2301 // purposes. 2302 llvm::SmallVector<NamedDecl*, 2> Chain; 2303 Chain.push_back(Anon); 2304 2305 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2306 Record->getDefinition(), 2307 AS_none, Chain, true)) 2308 Anon->setInvalidDecl(); 2309 2310 return Anon; 2311} 2312 2313/// GetNameForDeclarator - Determine the full declaration name for the 2314/// given Declarator. 2315DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2316 return GetNameFromUnqualifiedId(D.getName()); 2317} 2318 2319/// \brief Retrieves the declaration name from a parsed unqualified-id. 2320DeclarationNameInfo 2321Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2322 DeclarationNameInfo NameInfo; 2323 NameInfo.setLoc(Name.StartLocation); 2324 2325 switch (Name.getKind()) { 2326 2327 case UnqualifiedId::IK_Identifier: 2328 NameInfo.setName(Name.Identifier); 2329 NameInfo.setLoc(Name.StartLocation); 2330 return NameInfo; 2331 2332 case UnqualifiedId::IK_OperatorFunctionId: 2333 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2334 Name.OperatorFunctionId.Operator)); 2335 NameInfo.setLoc(Name.StartLocation); 2336 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2337 = Name.OperatorFunctionId.SymbolLocations[0]; 2338 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2339 = Name.EndLocation.getRawEncoding(); 2340 return NameInfo; 2341 2342 case UnqualifiedId::IK_LiteralOperatorId: 2343 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2344 Name.Identifier)); 2345 NameInfo.setLoc(Name.StartLocation); 2346 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2347 return NameInfo; 2348 2349 case UnqualifiedId::IK_ConversionFunctionId: { 2350 TypeSourceInfo *TInfo; 2351 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2352 if (Ty.isNull()) 2353 return DeclarationNameInfo(); 2354 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2355 Context.getCanonicalType(Ty))); 2356 NameInfo.setLoc(Name.StartLocation); 2357 NameInfo.setNamedTypeInfo(TInfo); 2358 return NameInfo; 2359 } 2360 2361 case UnqualifiedId::IK_ConstructorName: { 2362 TypeSourceInfo *TInfo; 2363 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2364 if (Ty.isNull()) 2365 return DeclarationNameInfo(); 2366 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2367 Context.getCanonicalType(Ty))); 2368 NameInfo.setLoc(Name.StartLocation); 2369 NameInfo.setNamedTypeInfo(TInfo); 2370 return NameInfo; 2371 } 2372 2373 case UnqualifiedId::IK_ConstructorTemplateId: { 2374 // In well-formed code, we can only have a constructor 2375 // template-id that refers to the current context, so go there 2376 // to find the actual type being constructed. 2377 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2378 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2379 return DeclarationNameInfo(); 2380 2381 // Determine the type of the class being constructed. 2382 QualType CurClassType = Context.getTypeDeclType(CurClass); 2383 2384 // FIXME: Check two things: that the template-id names the same type as 2385 // CurClassType, and that the template-id does not occur when the name 2386 // was qualified. 2387 2388 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2389 Context.getCanonicalType(CurClassType))); 2390 NameInfo.setLoc(Name.StartLocation); 2391 // FIXME: should we retrieve TypeSourceInfo? 2392 NameInfo.setNamedTypeInfo(0); 2393 return NameInfo; 2394 } 2395 2396 case UnqualifiedId::IK_DestructorName: { 2397 TypeSourceInfo *TInfo; 2398 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2399 if (Ty.isNull()) 2400 return DeclarationNameInfo(); 2401 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2402 Context.getCanonicalType(Ty))); 2403 NameInfo.setLoc(Name.StartLocation); 2404 NameInfo.setNamedTypeInfo(TInfo); 2405 return NameInfo; 2406 } 2407 2408 case UnqualifiedId::IK_TemplateId: { 2409 TemplateName TName = Name.TemplateId->Template.get(); 2410 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2411 return Context.getNameForTemplate(TName, TNameLoc); 2412 } 2413 2414 } // switch (Name.getKind()) 2415 2416 assert(false && "Unknown name kind"); 2417 return DeclarationNameInfo(); 2418} 2419 2420/// isNearlyMatchingFunction - Determine whether the C++ functions 2421/// Declaration and Definition are "nearly" matching. This heuristic 2422/// is used to improve diagnostics in the case where an out-of-line 2423/// function definition doesn't match any declaration within 2424/// the class or namespace. 2425static bool isNearlyMatchingFunction(ASTContext &Context, 2426 FunctionDecl *Declaration, 2427 FunctionDecl *Definition) { 2428 if (Declaration->param_size() != Definition->param_size()) 2429 return false; 2430 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2431 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2432 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2433 2434 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2435 DefParamTy.getNonReferenceType())) 2436 return false; 2437 } 2438 2439 return true; 2440} 2441 2442/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2443/// declarator needs to be rebuilt in the current instantiation. 2444/// Any bits of declarator which appear before the name are valid for 2445/// consideration here. That's specifically the type in the decl spec 2446/// and the base type in any member-pointer chunks. 2447static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2448 DeclarationName Name) { 2449 // The types we specifically need to rebuild are: 2450 // - typenames, typeofs, and decltypes 2451 // - types which will become injected class names 2452 // Of course, we also need to rebuild any type referencing such a 2453 // type. It's safest to just say "dependent", but we call out a 2454 // few cases here. 2455 2456 DeclSpec &DS = D.getMutableDeclSpec(); 2457 switch (DS.getTypeSpecType()) { 2458 case DeclSpec::TST_typename: 2459 case DeclSpec::TST_typeofType: 2460 case DeclSpec::TST_decltype: { 2461 // Grab the type from the parser. 2462 TypeSourceInfo *TSI = 0; 2463 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2464 if (T.isNull() || !T->isDependentType()) break; 2465 2466 // Make sure there's a type source info. This isn't really much 2467 // of a waste; most dependent types should have type source info 2468 // attached already. 2469 if (!TSI) 2470 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2471 2472 // Rebuild the type in the current instantiation. 2473 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2474 if (!TSI) return true; 2475 2476 // Store the new type back in the decl spec. 2477 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2478 DS.UpdateTypeRep(LocType); 2479 break; 2480 } 2481 2482 case DeclSpec::TST_typeofExpr: { 2483 Expr *E = DS.getRepAsExpr(); 2484 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2485 if (Result.isInvalid()) return true; 2486 DS.UpdateExprRep(Result.get()); 2487 break; 2488 } 2489 2490 default: 2491 // Nothing to do for these decl specs. 2492 break; 2493 } 2494 2495 // It doesn't matter what order we do this in. 2496 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2497 DeclaratorChunk &Chunk = D.getTypeObject(I); 2498 2499 // The only type information in the declarator which can come 2500 // before the declaration name is the base type of a member 2501 // pointer. 2502 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2503 continue; 2504 2505 // Rebuild the scope specifier in-place. 2506 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2507 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2508 return true; 2509 } 2510 2511 return false; 2512} 2513 2514Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2515 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2516} 2517 2518Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2519 MultiTemplateParamsArg TemplateParamLists, 2520 bool IsFunctionDefinition) { 2521 // TODO: consider using NameInfo for diagnostic. 2522 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2523 DeclarationName Name = NameInfo.getName(); 2524 2525 // All of these full declarators require an identifier. If it doesn't have 2526 // one, the ParsedFreeStandingDeclSpec action should be used. 2527 if (!Name) { 2528 if (!D.isInvalidType()) // Reject this if we think it is valid. 2529 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2530 diag::err_declarator_need_ident) 2531 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2532 return 0; 2533 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2534 return 0; 2535 2536 // The scope passed in may not be a decl scope. Zip up the scope tree until 2537 // we find one that is. 2538 while ((S->getFlags() & Scope::DeclScope) == 0 || 2539 (S->getFlags() & Scope::TemplateParamScope) != 0) 2540 S = S->getParent(); 2541 2542 DeclContext *DC = CurContext; 2543 if (D.getCXXScopeSpec().isInvalid()) 2544 D.setInvalidType(); 2545 else if (D.getCXXScopeSpec().isSet()) { 2546 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2547 UPPC_DeclarationQualifier)) 2548 return 0; 2549 2550 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2551 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2552 if (!DC) { 2553 // If we could not compute the declaration context, it's because the 2554 // declaration context is dependent but does not refer to a class, 2555 // class template, or class template partial specialization. Complain 2556 // and return early, to avoid the coming semantic disaster. 2557 Diag(D.getIdentifierLoc(), 2558 diag::err_template_qualified_declarator_no_match) 2559 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2560 << D.getCXXScopeSpec().getRange(); 2561 return 0; 2562 } 2563 2564 bool IsDependentContext = DC->isDependentContext(); 2565 2566 if (!IsDependentContext && 2567 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2568 return 0; 2569 2570 if (isa<CXXRecordDecl>(DC)) { 2571 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2572 Diag(D.getIdentifierLoc(), 2573 diag::err_member_def_undefined_record) 2574 << Name << DC << D.getCXXScopeSpec().getRange(); 2575 D.setInvalidType(); 2576 } else if (isa<CXXRecordDecl>(CurContext) && 2577 !D.getDeclSpec().isFriendSpecified()) { 2578 // The user provided a superfluous scope specifier inside a class 2579 // definition: 2580 // 2581 // class X { 2582 // void X::f(); 2583 // }; 2584 if (CurContext->Equals(DC)) 2585 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2586 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2587 else 2588 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2589 << Name << D.getCXXScopeSpec().getRange(); 2590 2591 // Pretend that this qualifier was not here. 2592 D.getCXXScopeSpec().clear(); 2593 } 2594 } 2595 2596 // Check whether we need to rebuild the type of the given 2597 // declaration in the current instantiation. 2598 if (EnteringContext && IsDependentContext && 2599 TemplateParamLists.size() != 0) { 2600 ContextRAII SavedContext(*this, DC); 2601 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2602 D.setInvalidType(); 2603 } 2604 } 2605 2606 // C++ [class.mem]p13: 2607 // If T is the name of a class, then each of the following shall have a 2608 // name different from T: 2609 // - every static data member of class T; 2610 // - every member function of class T 2611 // - every member of class T that is itself a type; 2612 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2613 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2614 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2615 << Name; 2616 2617 // If this is a typedef, we'll end up spewing multiple diagnostics. 2618 // Just return early; it's safer. 2619 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2620 return 0; 2621 } 2622 2623 NamedDecl *New; 2624 2625 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2626 QualType R = TInfo->getType(); 2627 2628 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 2629 UPPC_DeclarationType)) 2630 D.setInvalidType(); 2631 2632 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2633 ForRedeclaration); 2634 2635 // See if this is a redefinition of a variable in the same scope. 2636 if (!D.getCXXScopeSpec().isSet()) { 2637 bool IsLinkageLookup = false; 2638 2639 // If the declaration we're planning to build will be a function 2640 // or object with linkage, then look for another declaration with 2641 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2642 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2643 /* Do nothing*/; 2644 else if (R->isFunctionType()) { 2645 if (CurContext->isFunctionOrMethod() || 2646 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2647 IsLinkageLookup = true; 2648 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2649 IsLinkageLookup = true; 2650 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2651 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2652 IsLinkageLookup = true; 2653 2654 if (IsLinkageLookup) 2655 Previous.clear(LookupRedeclarationWithLinkage); 2656 2657 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2658 } else { // Something like "int foo::x;" 2659 LookupQualifiedName(Previous, DC); 2660 2661 // Don't consider using declarations as previous declarations for 2662 // out-of-line members. 2663 RemoveUsingDecls(Previous); 2664 2665 // C++ 7.3.1.2p2: 2666 // Members (including explicit specializations of templates) of a named 2667 // namespace can also be defined outside that namespace by explicit 2668 // qualification of the name being defined, provided that the entity being 2669 // defined was already declared in the namespace and the definition appears 2670 // after the point of declaration in a namespace that encloses the 2671 // declarations namespace. 2672 // 2673 // Note that we only check the context at this point. We don't yet 2674 // have enough information to make sure that PrevDecl is actually 2675 // the declaration we want to match. For example, given: 2676 // 2677 // class X { 2678 // void f(); 2679 // void f(float); 2680 // }; 2681 // 2682 // void X::f(int) { } // ill-formed 2683 // 2684 // In this case, PrevDecl will point to the overload set 2685 // containing the two f's declared in X, but neither of them 2686 // matches. 2687 2688 // First check whether we named the global scope. 2689 if (isa<TranslationUnitDecl>(DC)) { 2690 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2691 << Name << D.getCXXScopeSpec().getRange(); 2692 } else { 2693 DeclContext *Cur = CurContext; 2694 while (isa<LinkageSpecDecl>(Cur)) 2695 Cur = Cur->getParent(); 2696 if (!Cur->Encloses(DC)) { 2697 // The qualifying scope doesn't enclose the original declaration. 2698 // Emit diagnostic based on current scope. 2699 SourceLocation L = D.getIdentifierLoc(); 2700 SourceRange R = D.getCXXScopeSpec().getRange(); 2701 if (isa<FunctionDecl>(Cur)) 2702 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2703 else 2704 Diag(L, diag::err_invalid_declarator_scope) 2705 << Name << cast<NamedDecl>(DC) << R; 2706 D.setInvalidType(); 2707 } 2708 } 2709 } 2710 2711 if (Previous.isSingleResult() && 2712 Previous.getFoundDecl()->isTemplateParameter()) { 2713 // Maybe we will complain about the shadowed template parameter. 2714 if (!D.isInvalidType()) 2715 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2716 Previous.getFoundDecl())) 2717 D.setInvalidType(); 2718 2719 // Just pretend that we didn't see the previous declaration. 2720 Previous.clear(); 2721 } 2722 2723 // In C++, the previous declaration we find might be a tag type 2724 // (class or enum). In this case, the new declaration will hide the 2725 // tag type. Note that this does does not apply if we're declaring a 2726 // typedef (C++ [dcl.typedef]p4). 2727 if (Previous.isSingleTagDecl() && 2728 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2729 Previous.clear(); 2730 2731 bool Redeclaration = false; 2732 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2733 if (TemplateParamLists.size()) { 2734 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2735 return 0; 2736 } 2737 2738 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2739 } else if (R->isFunctionType()) { 2740 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2741 move(TemplateParamLists), 2742 IsFunctionDefinition, Redeclaration); 2743 } else { 2744 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2745 move(TemplateParamLists), 2746 Redeclaration); 2747 } 2748 2749 if (New == 0) 2750 return 0; 2751 2752 // If this has an identifier and is not an invalid redeclaration or 2753 // function template specialization, add it to the scope stack. 2754 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2755 PushOnScopeChains(New, S); 2756 2757 return New; 2758} 2759 2760/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2761/// types into constant array types in certain situations which would otherwise 2762/// be errors (for GCC compatibility). 2763static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2764 ASTContext &Context, 2765 bool &SizeIsNegative, 2766 llvm::APSInt &Oversized) { 2767 // This method tries to turn a variable array into a constant 2768 // array even when the size isn't an ICE. This is necessary 2769 // for compatibility with code that depends on gcc's buggy 2770 // constant expression folding, like struct {char x[(int)(char*)2];} 2771 SizeIsNegative = false; 2772 Oversized = 0; 2773 2774 if (T->isDependentType()) 2775 return QualType(); 2776 2777 QualifierCollector Qs; 2778 const Type *Ty = Qs.strip(T); 2779 2780 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2781 QualType Pointee = PTy->getPointeeType(); 2782 QualType FixedType = 2783 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2784 Oversized); 2785 if (FixedType.isNull()) return FixedType; 2786 FixedType = Context.getPointerType(FixedType); 2787 return Qs.apply(Context, FixedType); 2788 } 2789 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 2790 QualType Inner = PTy->getInnerType(); 2791 QualType FixedType = 2792 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 2793 Oversized); 2794 if (FixedType.isNull()) return FixedType; 2795 FixedType = Context.getParenType(FixedType); 2796 return Qs.apply(Context, FixedType); 2797 } 2798 2799 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2800 if (!VLATy) 2801 return QualType(); 2802 // FIXME: We should probably handle this case 2803 if (VLATy->getElementType()->isVariablyModifiedType()) 2804 return QualType(); 2805 2806 Expr::EvalResult EvalResult; 2807 if (!VLATy->getSizeExpr() || 2808 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2809 !EvalResult.Val.isInt()) 2810 return QualType(); 2811 2812 // Check whether the array size is negative. 2813 llvm::APSInt &Res = EvalResult.Val.getInt(); 2814 if (Res.isSigned() && Res.isNegative()) { 2815 SizeIsNegative = true; 2816 return QualType(); 2817 } 2818 2819 // Check whether the array is too large to be addressed. 2820 unsigned ActiveSizeBits 2821 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2822 Res); 2823 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2824 Oversized = Res; 2825 return QualType(); 2826 } 2827 2828 return Context.getConstantArrayType(VLATy->getElementType(), 2829 Res, ArrayType::Normal, 0); 2830} 2831 2832/// \brief Register the given locally-scoped external C declaration so 2833/// that it can be found later for redeclarations 2834void 2835Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2836 const LookupResult &Previous, 2837 Scope *S) { 2838 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2839 "Decl is not a locally-scoped decl!"); 2840 // Note that we have a locally-scoped external with this name. 2841 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2842 2843 if (!Previous.isSingleResult()) 2844 return; 2845 2846 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2847 2848 // If there was a previous declaration of this variable, it may be 2849 // in our identifier chain. Update the identifier chain with the new 2850 // declaration. 2851 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2852 // The previous declaration was found on the identifer resolver 2853 // chain, so remove it from its scope. 2854 while (S && !S->isDeclScope(PrevDecl)) 2855 S = S->getParent(); 2856 2857 if (S) 2858 S->RemoveDecl(PrevDecl); 2859 } 2860} 2861 2862/// \brief Diagnose function specifiers on a declaration of an identifier that 2863/// does not identify a function. 2864void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2865 // FIXME: We should probably indicate the identifier in question to avoid 2866 // confusion for constructs like "inline int a(), b;" 2867 if (D.getDeclSpec().isInlineSpecified()) 2868 Diag(D.getDeclSpec().getInlineSpecLoc(), 2869 diag::err_inline_non_function); 2870 2871 if (D.getDeclSpec().isVirtualSpecified()) 2872 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2873 diag::err_virtual_non_function); 2874 2875 if (D.getDeclSpec().isExplicitSpecified()) 2876 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2877 diag::err_explicit_non_function); 2878} 2879 2880NamedDecl* 2881Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2882 QualType R, TypeSourceInfo *TInfo, 2883 LookupResult &Previous, bool &Redeclaration) { 2884 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2885 if (D.getCXXScopeSpec().isSet()) { 2886 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2887 << D.getCXXScopeSpec().getRange(); 2888 D.setInvalidType(); 2889 // Pretend we didn't see the scope specifier. 2890 DC = CurContext; 2891 Previous.clear(); 2892 } 2893 2894 if (getLangOptions().CPlusPlus) { 2895 // Check that there are no default arguments (C++ only). 2896 CheckExtraCXXDefaultArguments(D); 2897 } 2898 2899 DiagnoseFunctionSpecifiers(D); 2900 2901 if (D.getDeclSpec().isThreadSpecified()) 2902 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2903 2904 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2905 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2906 << D.getName().getSourceRange(); 2907 return 0; 2908 } 2909 2910 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2911 if (!NewTD) return 0; 2912 2913 // Handle attributes prior to checking for duplicates in MergeVarDecl 2914 ProcessDeclAttributes(S, NewTD, D); 2915 2916 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2917 // then it shall have block scope. 2918 // Note that variably modified types must be fixed before merging the decl so 2919 // that redeclarations will match. 2920 QualType T = NewTD->getUnderlyingType(); 2921 if (T->isVariablyModifiedType()) { 2922 getCurFunction()->setHasBranchProtectedScope(); 2923 2924 if (S->getFnParent() == 0) { 2925 bool SizeIsNegative; 2926 llvm::APSInt Oversized; 2927 QualType FixedTy = 2928 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2929 Oversized); 2930 if (!FixedTy.isNull()) { 2931 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2932 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2933 } else { 2934 if (SizeIsNegative) 2935 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2936 else if (T->isVariableArrayType()) 2937 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2938 else if (Oversized.getBoolValue()) 2939 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2940 << Oversized.toString(10); 2941 else 2942 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2943 NewTD->setInvalidDecl(); 2944 } 2945 } 2946 } 2947 2948 // Merge the decl with the existing one if appropriate. If the decl is 2949 // in an outer scope, it isn't the same thing. 2950 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false, 2951 /*ExplicitInstantiationOrSpecialization=*/false); 2952 if (!Previous.empty()) { 2953 Redeclaration = true; 2954 MergeTypeDefDecl(NewTD, Previous); 2955 } 2956 2957 // If this is the C FILE type, notify the AST context. 2958 if (IdentifierInfo *II = NewTD->getIdentifier()) 2959 if (!NewTD->isInvalidDecl() && 2960 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2961 if (II->isStr("FILE")) 2962 Context.setFILEDecl(NewTD); 2963 else if (II->isStr("jmp_buf")) 2964 Context.setjmp_bufDecl(NewTD); 2965 else if (II->isStr("sigjmp_buf")) 2966 Context.setsigjmp_bufDecl(NewTD); 2967 else if (II->isStr("__builtin_va_list")) 2968 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2969 } 2970 2971 return NewTD; 2972} 2973 2974/// \brief Determines whether the given declaration is an out-of-scope 2975/// previous declaration. 2976/// 2977/// This routine should be invoked when name lookup has found a 2978/// previous declaration (PrevDecl) that is not in the scope where a 2979/// new declaration by the same name is being introduced. If the new 2980/// declaration occurs in a local scope, previous declarations with 2981/// linkage may still be considered previous declarations (C99 2982/// 6.2.2p4-5, C++ [basic.link]p6). 2983/// 2984/// \param PrevDecl the previous declaration found by name 2985/// lookup 2986/// 2987/// \param DC the context in which the new declaration is being 2988/// declared. 2989/// 2990/// \returns true if PrevDecl is an out-of-scope previous declaration 2991/// for a new delcaration with the same name. 2992static bool 2993isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2994 ASTContext &Context) { 2995 if (!PrevDecl) 2996 return false; 2997 2998 if (!PrevDecl->hasLinkage()) 2999 return false; 3000 3001 if (Context.getLangOptions().CPlusPlus) { 3002 // C++ [basic.link]p6: 3003 // If there is a visible declaration of an entity with linkage 3004 // having the same name and type, ignoring entities declared 3005 // outside the innermost enclosing namespace scope, the block 3006 // scope declaration declares that same entity and receives the 3007 // linkage of the previous declaration. 3008 DeclContext *OuterContext = DC->getRedeclContext(); 3009 if (!OuterContext->isFunctionOrMethod()) 3010 // This rule only applies to block-scope declarations. 3011 return false; 3012 3013 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 3014 if (PrevOuterContext->isRecord()) 3015 // We found a member function: ignore it. 3016 return false; 3017 3018 // Find the innermost enclosing namespace for the new and 3019 // previous declarations. 3020 OuterContext = OuterContext->getEnclosingNamespaceContext(); 3021 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 3022 3023 // The previous declaration is in a different namespace, so it 3024 // isn't the same function. 3025 if (!OuterContext->Equals(PrevOuterContext)) 3026 return false; 3027 } 3028 3029 return true; 3030} 3031 3032static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 3033 CXXScopeSpec &SS = D.getCXXScopeSpec(); 3034 if (!SS.isSet()) return; 3035 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 3036} 3037 3038NamedDecl* 3039Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 3040 QualType R, TypeSourceInfo *TInfo, 3041 LookupResult &Previous, 3042 MultiTemplateParamsArg TemplateParamLists, 3043 bool &Redeclaration) { 3044 DeclarationName Name = GetNameForDeclarator(D).getName(); 3045 3046 // Check that there are no default arguments (C++ only). 3047 if (getLangOptions().CPlusPlus) 3048 CheckExtraCXXDefaultArguments(D); 3049 3050 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 3051 assert(SCSpec != DeclSpec::SCS_typedef && 3052 "Parser allowed 'typedef' as storage class VarDecl."); 3053 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 3054 if (SCSpec == DeclSpec::SCS_mutable) { 3055 // mutable can only appear on non-static class members, so it's always 3056 // an error here 3057 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 3058 D.setInvalidType(); 3059 SC = SC_None; 3060 } 3061 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3062 VarDecl::StorageClass SCAsWritten 3063 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3064 3065 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3066 if (!II) { 3067 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3068 << Name.getAsString(); 3069 return 0; 3070 } 3071 3072 DiagnoseFunctionSpecifiers(D); 3073 3074 if (!DC->isRecord() && S->getFnParent() == 0) { 3075 // C99 6.9p2: The storage-class specifiers auto and register shall not 3076 // appear in the declaration specifiers in an external declaration. 3077 if (SC == SC_Auto || SC == SC_Register) { 3078 3079 // If this is a register variable with an asm label specified, then this 3080 // is a GNU extension. 3081 if (SC == SC_Register && D.getAsmLabel()) 3082 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3083 else 3084 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3085 D.setInvalidType(); 3086 } 3087 } 3088 3089 bool isExplicitSpecialization = false; 3090 VarDecl *NewVD; 3091 if (!getLangOptions().CPlusPlus) { 3092 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3093 D.getIdentifierLoc(), II, 3094 R, TInfo, SC, SCAsWritten); 3095 3096 if (D.isInvalidType()) 3097 NewVD->setInvalidDecl(); 3098 } else { 3099 if (DC->isRecord() && !CurContext->isRecord()) { 3100 // This is an out-of-line definition of a static data member. 3101 if (SC == SC_Static) { 3102 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3103 diag::err_static_out_of_line) 3104 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3105 } else if (SC == SC_None) 3106 SC = SC_Static; 3107 } 3108 if (SC == SC_Static) { 3109 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3110 if (RD->isLocalClass()) 3111 Diag(D.getIdentifierLoc(), 3112 diag::err_static_data_member_not_allowed_in_local_class) 3113 << Name << RD->getDeclName(); 3114 3115 // C++ [class.union]p1: If a union contains a static data member, 3116 // the program is ill-formed. 3117 // 3118 // We also disallow static data members in anonymous structs. 3119 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3120 Diag(D.getIdentifierLoc(), 3121 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3122 << Name << RD->isUnion(); 3123 } 3124 } 3125 3126 // Match up the template parameter lists with the scope specifier, then 3127 // determine whether we have a template or a template specialization. 3128 isExplicitSpecialization = false; 3129 bool Invalid = false; 3130 if (TemplateParameterList *TemplateParams 3131 = MatchTemplateParametersToScopeSpecifier( 3132 D.getDeclSpec().getSourceRange().getBegin(), 3133 D.getCXXScopeSpec(), 3134 TemplateParamLists.get(), 3135 TemplateParamLists.size(), 3136 /*never a friend*/ false, 3137 isExplicitSpecialization, 3138 Invalid)) { 3139 if (TemplateParams->size() > 0) { 3140 // There is no such thing as a variable template. 3141 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3142 << II 3143 << SourceRange(TemplateParams->getTemplateLoc(), 3144 TemplateParams->getRAngleLoc()); 3145 return 0; 3146 } else { 3147 // There is an extraneous 'template<>' for this variable. Complain 3148 // about it, but allow the declaration of the variable. 3149 Diag(TemplateParams->getTemplateLoc(), 3150 diag::err_template_variable_noparams) 3151 << II 3152 << SourceRange(TemplateParams->getTemplateLoc(), 3153 TemplateParams->getRAngleLoc()); 3154 isExplicitSpecialization = true; 3155 } 3156 } 3157 3158 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3159 D.getIdentifierLoc(), II, 3160 R, TInfo, SC, SCAsWritten); 3161 3162 // If this decl has an auto type in need of deduction, make a note of the 3163 // Decl so we can diagnose uses of it in its own initializer. 3164 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3165 R->getContainedAutoType()) 3166 ParsingInitForAutoVars.insert(NewVD); 3167 3168 if (D.isInvalidType() || Invalid) 3169 NewVD->setInvalidDecl(); 3170 3171 SetNestedNameSpecifier(NewVD, D); 3172 3173 if (TemplateParamLists.size() > 0 && D.getCXXScopeSpec().isSet()) { 3174 NewVD->setTemplateParameterListsInfo(Context, 3175 TemplateParamLists.size(), 3176 TemplateParamLists.release()); 3177 } 3178 } 3179 3180 if (D.getDeclSpec().isThreadSpecified()) { 3181 if (NewVD->hasLocalStorage()) 3182 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3183 else if (!Context.Target.isTLSSupported()) 3184 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3185 else 3186 NewVD->setThreadSpecified(true); 3187 } 3188 3189 // Set the lexical context. If the declarator has a C++ scope specifier, the 3190 // lexical context will be different from the semantic context. 3191 NewVD->setLexicalDeclContext(CurContext); 3192 3193 // Handle attributes prior to checking for duplicates in MergeVarDecl 3194 ProcessDeclAttributes(S, NewVD, D); 3195 3196 // Handle GNU asm-label extension (encoded as an attribute). 3197 if (Expr *E = (Expr*)D.getAsmLabel()) { 3198 // The parser guarantees this is a string. 3199 StringLiteral *SE = cast<StringLiteral>(E); 3200 llvm::StringRef Label = SE->getString(); 3201 if (S->getFnParent() != 0) { 3202 switch (SC) { 3203 case SC_None: 3204 case SC_Auto: 3205 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3206 break; 3207 case SC_Register: 3208 if (!Context.Target.isValidGCCRegisterName(Label)) 3209 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3210 break; 3211 case SC_Static: 3212 case SC_Extern: 3213 case SC_PrivateExtern: 3214 break; 3215 } 3216 } 3217 3218 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3219 Context, Label)); 3220 } 3221 3222 // Diagnose shadowed variables before filtering for scope. 3223 if (!D.getCXXScopeSpec().isSet()) 3224 CheckShadow(S, NewVD, Previous); 3225 3226 // Don't consider existing declarations that are in a different 3227 // scope and are out-of-semantic-context declarations (if the new 3228 // declaration has linkage). 3229 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage(), 3230 isExplicitSpecialization); 3231 3232 if (!getLangOptions().CPlusPlus) 3233 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3234 else { 3235 // Merge the decl with the existing one if appropriate. 3236 if (!Previous.empty()) { 3237 if (Previous.isSingleResult() && 3238 isa<FieldDecl>(Previous.getFoundDecl()) && 3239 D.getCXXScopeSpec().isSet()) { 3240 // The user tried to define a non-static data member 3241 // out-of-line (C++ [dcl.meaning]p1). 3242 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3243 << D.getCXXScopeSpec().getRange(); 3244 Previous.clear(); 3245 NewVD->setInvalidDecl(); 3246 } 3247 } else if (D.getCXXScopeSpec().isSet()) { 3248 // No previous declaration in the qualifying scope. 3249 Diag(D.getIdentifierLoc(), diag::err_no_member) 3250 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3251 << D.getCXXScopeSpec().getRange(); 3252 NewVD->setInvalidDecl(); 3253 } 3254 3255 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3256 3257 // This is an explicit specialization of a static data member. Check it. 3258 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3259 CheckMemberSpecialization(NewVD, Previous)) 3260 NewVD->setInvalidDecl(); 3261 } 3262 3263 // attributes declared post-definition are currently ignored 3264 // FIXME: This should be handled in attribute merging, not 3265 // here. 3266 if (Previous.isSingleResult()) { 3267 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3268 if (Def && (Def = Def->getDefinition()) && 3269 Def != NewVD && D.hasAttributes()) { 3270 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3271 Diag(Def->getLocation(), diag::note_previous_definition); 3272 } 3273 } 3274 3275 // If this is a locally-scoped extern C variable, update the map of 3276 // such variables. 3277 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3278 !NewVD->isInvalidDecl()) 3279 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3280 3281 // If there's a #pragma GCC visibility in scope, and this isn't a class 3282 // member, set the visibility of this variable. 3283 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3284 AddPushedVisibilityAttribute(NewVD); 3285 3286 MarkUnusedFileScopedDecl(NewVD); 3287 3288 return NewVD; 3289} 3290 3291/// \brief Diagnose variable or built-in function shadowing. Implements 3292/// -Wshadow. 3293/// 3294/// This method is called whenever a VarDecl is added to a "useful" 3295/// scope. 3296/// 3297/// \param S the scope in which the shadowing name is being declared 3298/// \param R the lookup of the name 3299/// 3300void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3301 // Return if warning is ignored. 3302 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3303 Diagnostic::Ignored) 3304 return; 3305 3306 // Don't diagnose declarations at file scope. 3307 DeclContext *NewDC = D->getDeclContext(); 3308 if (NewDC->isFileContext()) 3309 return; 3310 3311 // Only diagnose if we're shadowing an unambiguous field or variable. 3312 if (R.getResultKind() != LookupResult::Found) 3313 return; 3314 3315 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3316 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3317 return; 3318 3319 // Fields are not shadowed by variables in C++ static methods. 3320 if (isa<FieldDecl>(ShadowedDecl)) 3321 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3322 if (MD->isStatic()) 3323 return; 3324 3325 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3326 if (shadowedVar->isExternC()) { 3327 // Don't warn for this case: 3328 // 3329 // @code 3330 // extern int bob; 3331 // void f() { 3332 // extern int bob; 3333 // } 3334 // @endcode 3335 if (D->isExternC()) 3336 return; 3337 3338 // For shadowing external vars, make sure that we point to the global 3339 // declaration, not a locally scoped extern declaration. 3340 for (VarDecl::redecl_iterator 3341 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3342 I != E; ++I) 3343 if (I->isFileVarDecl()) { 3344 ShadowedDecl = *I; 3345 break; 3346 } 3347 } 3348 3349 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3350 3351 // Only warn about certain kinds of shadowing for class members. 3352 if (NewDC && NewDC->isRecord()) { 3353 // In particular, don't warn about shadowing non-class members. 3354 if (!OldDC->isRecord()) 3355 return; 3356 3357 // TODO: should we warn about static data members shadowing 3358 // static data members from base classes? 3359 3360 // TODO: don't diagnose for inaccessible shadowed members. 3361 // This is hard to do perfectly because we might friend the 3362 // shadowing context, but that's just a false negative. 3363 } 3364 3365 // Determine what kind of declaration we're shadowing. 3366 unsigned Kind; 3367 if (isa<RecordDecl>(OldDC)) { 3368 if (isa<FieldDecl>(ShadowedDecl)) 3369 Kind = 3; // field 3370 else 3371 Kind = 2; // static data member 3372 } else if (OldDC->isFileContext()) 3373 Kind = 1; // global 3374 else 3375 Kind = 0; // local 3376 3377 DeclarationName Name = R.getLookupName(); 3378 3379 // Emit warning and note. 3380 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3381 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3382} 3383 3384/// \brief Check -Wshadow without the advantage of a previous lookup. 3385void Sema::CheckShadow(Scope *S, VarDecl *D) { 3386 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3387 Diagnostic::Ignored) 3388 return; 3389 3390 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3391 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3392 LookupName(R, S); 3393 CheckShadow(S, D, R); 3394} 3395 3396/// \brief Perform semantic checking on a newly-created variable 3397/// declaration. 3398/// 3399/// This routine performs all of the type-checking required for a 3400/// variable declaration once it has been built. It is used both to 3401/// check variables after they have been parsed and their declarators 3402/// have been translated into a declaration, and to check variables 3403/// that have been instantiated from a template. 3404/// 3405/// Sets NewVD->isInvalidDecl() if an error was encountered. 3406void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3407 LookupResult &Previous, 3408 bool &Redeclaration) { 3409 // If the decl is already known invalid, don't check it. 3410 if (NewVD->isInvalidDecl()) 3411 return; 3412 3413 QualType T = NewVD->getType(); 3414 3415 if (T->isObjCObjectType()) { 3416 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3417 return NewVD->setInvalidDecl(); 3418 } 3419 3420 // Emit an error if an address space was applied to decl with local storage. 3421 // This includes arrays of objects with address space qualifiers, but not 3422 // automatic variables that point to other address spaces. 3423 // ISO/IEC TR 18037 S5.1.2 3424 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3425 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3426 return NewVD->setInvalidDecl(); 3427 } 3428 3429 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3430 && !NewVD->hasAttr<BlocksAttr>()) 3431 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3432 3433 bool isVM = T->isVariablyModifiedType(); 3434 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3435 NewVD->hasAttr<BlocksAttr>()) 3436 getCurFunction()->setHasBranchProtectedScope(); 3437 3438 if ((isVM && NewVD->hasLinkage()) || 3439 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3440 bool SizeIsNegative; 3441 llvm::APSInt Oversized; 3442 QualType FixedTy = 3443 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3444 Oversized); 3445 3446 if (FixedTy.isNull() && T->isVariableArrayType()) { 3447 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3448 // FIXME: This won't give the correct result for 3449 // int a[10][n]; 3450 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3451 3452 if (NewVD->isFileVarDecl()) 3453 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3454 << SizeRange; 3455 else if (NewVD->getStorageClass() == SC_Static) 3456 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3457 << SizeRange; 3458 else 3459 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3460 << SizeRange; 3461 return NewVD->setInvalidDecl(); 3462 } 3463 3464 if (FixedTy.isNull()) { 3465 if (NewVD->isFileVarDecl()) 3466 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3467 else 3468 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3469 return NewVD->setInvalidDecl(); 3470 } 3471 3472 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3473 NewVD->setType(FixedTy); 3474 } 3475 3476 if (Previous.empty() && NewVD->isExternC()) { 3477 // Since we did not find anything by this name and we're declaring 3478 // an extern "C" variable, look for a non-visible extern "C" 3479 // declaration with the same name. 3480 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3481 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3482 if (Pos != LocallyScopedExternalDecls.end()) 3483 Previous.addDecl(Pos->second); 3484 } 3485 3486 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3487 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3488 << T; 3489 return NewVD->setInvalidDecl(); 3490 } 3491 3492 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3493 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3494 return NewVD->setInvalidDecl(); 3495 } 3496 3497 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3498 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3499 return NewVD->setInvalidDecl(); 3500 } 3501 3502 // Function pointers and references cannot have qualified function type, only 3503 // function pointer-to-members can do that. 3504 QualType Pointee; 3505 unsigned PtrOrRef = 0; 3506 if (const PointerType *Ptr = T->getAs<PointerType>()) 3507 Pointee = Ptr->getPointeeType(); 3508 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3509 Pointee = Ref->getPointeeType(); 3510 PtrOrRef = 1; 3511 } 3512 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3513 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3514 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3515 << PtrOrRef; 3516 return NewVD->setInvalidDecl(); 3517 } 3518 3519 if (!Previous.empty()) { 3520 Redeclaration = true; 3521 MergeVarDecl(NewVD, Previous); 3522 } 3523} 3524 3525/// \brief Data used with FindOverriddenMethod 3526struct FindOverriddenMethodData { 3527 Sema *S; 3528 CXXMethodDecl *Method; 3529}; 3530 3531/// \brief Member lookup function that determines whether a given C++ 3532/// method overrides a method in a base class, to be used with 3533/// CXXRecordDecl::lookupInBases(). 3534static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3535 CXXBasePath &Path, 3536 void *UserData) { 3537 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3538 3539 FindOverriddenMethodData *Data 3540 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3541 3542 DeclarationName Name = Data->Method->getDeclName(); 3543 3544 // FIXME: Do we care about other names here too? 3545 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3546 // We really want to find the base class destructor here. 3547 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3548 CanQualType CT = Data->S->Context.getCanonicalType(T); 3549 3550 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3551 } 3552 3553 for (Path.Decls = BaseRecord->lookup(Name); 3554 Path.Decls.first != Path.Decls.second; 3555 ++Path.Decls.first) { 3556 NamedDecl *D = *Path.Decls.first; 3557 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3558 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3559 return true; 3560 } 3561 } 3562 3563 return false; 3564} 3565 3566/// AddOverriddenMethods - See if a method overrides any in the base classes, 3567/// and if so, check that it's a valid override and remember it. 3568bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3569 // Look for virtual methods in base classes that this method might override. 3570 CXXBasePaths Paths; 3571 FindOverriddenMethodData Data; 3572 Data.Method = MD; 3573 Data.S = this; 3574 bool AddedAny = false; 3575 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3576 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3577 E = Paths.found_decls_end(); I != E; ++I) { 3578 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3579 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3580 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3581 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 3582 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3583 AddedAny = true; 3584 } 3585 } 3586 } 3587 } 3588 3589 return AddedAny; 3590} 3591 3592static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3593 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3594 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3595 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3596 assert(!Prev.isAmbiguous() && 3597 "Cannot have an ambiguity in previous-declaration lookup"); 3598 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3599 Func != FuncEnd; ++Func) { 3600 if (isa<FunctionDecl>(*Func) && 3601 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3602 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3603 } 3604} 3605 3606NamedDecl* 3607Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3608 QualType R, TypeSourceInfo *TInfo, 3609 LookupResult &Previous, 3610 MultiTemplateParamsArg TemplateParamLists, 3611 bool IsFunctionDefinition, bool &Redeclaration) { 3612 assert(R.getTypePtr()->isFunctionType()); 3613 3614 // TODO: consider using NameInfo for diagnostic. 3615 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3616 DeclarationName Name = NameInfo.getName(); 3617 FunctionDecl::StorageClass SC = SC_None; 3618 switch (D.getDeclSpec().getStorageClassSpec()) { 3619 default: assert(0 && "Unknown storage class!"); 3620 case DeclSpec::SCS_auto: 3621 case DeclSpec::SCS_register: 3622 case DeclSpec::SCS_mutable: 3623 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3624 diag::err_typecheck_sclass_func); 3625 D.setInvalidType(); 3626 break; 3627 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3628 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3629 case DeclSpec::SCS_static: { 3630 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3631 // C99 6.7.1p5: 3632 // The declaration of an identifier for a function that has 3633 // block scope shall have no explicit storage-class specifier 3634 // other than extern 3635 // See also (C++ [dcl.stc]p4). 3636 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3637 diag::err_static_block_func); 3638 SC = SC_None; 3639 } else 3640 SC = SC_Static; 3641 break; 3642 } 3643 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3644 } 3645 3646 if (D.getDeclSpec().isThreadSpecified()) 3647 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3648 3649 // Do not allow returning a objc interface by-value. 3650 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3651 Diag(D.getIdentifierLoc(), 3652 diag::err_object_cannot_be_passed_returned_by_value) << 0 3653 << R->getAs<FunctionType>()->getResultType(); 3654 D.setInvalidType(); 3655 } 3656 3657 FunctionDecl *NewFD; 3658 bool isInline = D.getDeclSpec().isInlineSpecified(); 3659 bool isFriend = false; 3660 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3661 FunctionDecl::StorageClass SCAsWritten 3662 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3663 FunctionTemplateDecl *FunctionTemplate = 0; 3664 bool isExplicitSpecialization = false; 3665 bool isFunctionTemplateSpecialization = false; 3666 3667 if (!getLangOptions().CPlusPlus) { 3668 // Determine whether the function was written with a 3669 // prototype. This true when: 3670 // - there is a prototype in the declarator, or 3671 // - the type R of the function is some kind of typedef or other reference 3672 // to a type name (which eventually refers to a function type). 3673 bool HasPrototype = 3674 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 3675 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3676 3677 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3678 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3679 HasPrototype); 3680 if (D.isInvalidType()) 3681 NewFD->setInvalidDecl(); 3682 3683 // Set the lexical context. 3684 NewFD->setLexicalDeclContext(CurContext); 3685 // Filter out previous declarations that don't match the scope. 3686 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage(), 3687 /*ExplicitInstantiationOrSpecialization=*/false); 3688 } else { 3689 isFriend = D.getDeclSpec().isFriendSpecified(); 3690 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3691 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3692 bool isVirtualOkay = false; 3693 3694 // Check that the return type is not an abstract class type. 3695 // For record types, this is done by the AbstractClassUsageDiagnoser once 3696 // the class has been completely parsed. 3697 if (!DC->isRecord() && 3698 RequireNonAbstractType(D.getIdentifierLoc(), 3699 R->getAs<FunctionType>()->getResultType(), 3700 diag::err_abstract_type_in_decl, 3701 AbstractReturnType)) 3702 D.setInvalidType(); 3703 3704 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3705 // This is a C++ constructor declaration. 3706 assert(DC->isRecord() && 3707 "Constructors can only be declared in a member context"); 3708 3709 R = CheckConstructorDeclarator(D, R, SC); 3710 3711 // Create the new declaration 3712 NewFD = CXXConstructorDecl::Create(Context, 3713 cast<CXXRecordDecl>(DC), 3714 D.getSourceRange().getBegin(), 3715 NameInfo, R, TInfo, 3716 isExplicit, isInline, 3717 /*isImplicitlyDeclared=*/false); 3718 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3719 // This is a C++ destructor declaration. 3720 if (DC->isRecord()) { 3721 R = CheckDestructorDeclarator(D, R, SC); 3722 3723 NewFD = CXXDestructorDecl::Create(Context, 3724 cast<CXXRecordDecl>(DC), 3725 D.getSourceRange().getBegin(), 3726 NameInfo, R, TInfo, 3727 isInline, 3728 /*isImplicitlyDeclared=*/false); 3729 isVirtualOkay = true; 3730 } else { 3731 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3732 3733 // Create a FunctionDecl to satisfy the function definition parsing 3734 // code path. 3735 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3736 D.getIdentifierLoc(), Name, R, TInfo, 3737 SC, SCAsWritten, isInline, 3738 /*hasPrototype=*/true); 3739 D.setInvalidType(); 3740 } 3741 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3742 if (!DC->isRecord()) { 3743 Diag(D.getIdentifierLoc(), 3744 diag::err_conv_function_not_member); 3745 return 0; 3746 } 3747 3748 CheckConversionDeclarator(D, R, SC); 3749 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3750 D.getSourceRange().getBegin(), 3751 NameInfo, R, TInfo, 3752 isInline, isExplicit, 3753 SourceLocation()); 3754 3755 isVirtualOkay = true; 3756 } else if (DC->isRecord()) { 3757 // If the of the function is the same as the name of the record, then this 3758 // must be an invalid constructor that has a return type. 3759 // (The parser checks for a return type and makes the declarator a 3760 // constructor if it has no return type). 3761 // must have an invalid constructor that has a return type 3762 if (Name.getAsIdentifierInfo() && 3763 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3764 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3765 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3766 << SourceRange(D.getIdentifierLoc()); 3767 return 0; 3768 } 3769 3770 bool isStatic = SC == SC_Static; 3771 3772 // [class.free]p1: 3773 // Any allocation function for a class T is a static member 3774 // (even if not explicitly declared static). 3775 if (Name.getCXXOverloadedOperator() == OO_New || 3776 Name.getCXXOverloadedOperator() == OO_Array_New) 3777 isStatic = true; 3778 3779 // [class.free]p6 Any deallocation function for a class X is a static member 3780 // (even if not explicitly declared static). 3781 if (Name.getCXXOverloadedOperator() == OO_Delete || 3782 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3783 isStatic = true; 3784 3785 // This is a C++ method declaration. 3786 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3787 D.getSourceRange().getBegin(), 3788 NameInfo, R, TInfo, 3789 isStatic, SCAsWritten, isInline, 3790 SourceLocation()); 3791 3792 isVirtualOkay = !isStatic; 3793 } else { 3794 // Determine whether the function was written with a 3795 // prototype. This true when: 3796 // - we're in C++ (where every function has a prototype), 3797 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3798 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3799 true/*HasPrototype*/); 3800 } 3801 3802 if (isFriend && !isInline && IsFunctionDefinition) { 3803 // C++ [class.friend]p5 3804 // A function can be defined in a friend declaration of a 3805 // class . . . . Such a function is implicitly inline. 3806 NewFD->setImplicitlyInline(); 3807 } 3808 3809 SetNestedNameSpecifier(NewFD, D); 3810 isExplicitSpecialization = false; 3811 isFunctionTemplateSpecialization = false; 3812 if (D.isInvalidType()) 3813 NewFD->setInvalidDecl(); 3814 3815 // Set the lexical context. If the declarator has a C++ 3816 // scope specifier, or is the object of a friend declaration, the 3817 // lexical context will be different from the semantic context. 3818 NewFD->setLexicalDeclContext(CurContext); 3819 3820 // Match up the template parameter lists with the scope specifier, then 3821 // determine whether we have a template or a template specialization. 3822 bool Invalid = false; 3823 if (TemplateParameterList *TemplateParams 3824 = MatchTemplateParametersToScopeSpecifier( 3825 D.getDeclSpec().getSourceRange().getBegin(), 3826 D.getCXXScopeSpec(), 3827 TemplateParamLists.get(), 3828 TemplateParamLists.size(), 3829 isFriend, 3830 isExplicitSpecialization, 3831 Invalid)) { 3832 if (TemplateParams->size() > 0) { 3833 // This is a function template 3834 3835 // Check that we can declare a template here. 3836 if (CheckTemplateDeclScope(S, TemplateParams)) 3837 return 0; 3838 3839 // A destructor cannot be a template. 3840 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3841 Diag(NewFD->getLocation(), diag::err_destructor_template); 3842 return 0; 3843 } 3844 3845 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3846 NewFD->getLocation(), 3847 Name, TemplateParams, 3848 NewFD); 3849 FunctionTemplate->setLexicalDeclContext(CurContext); 3850 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3851 3852 // For source fidelity, store the other template param lists. 3853 if (TemplateParamLists.size() > 1) { 3854 NewFD->setTemplateParameterListsInfo(Context, 3855 TemplateParamLists.size() - 1, 3856 TemplateParamLists.release()); 3857 } 3858 } else { 3859 // This is a function template specialization. 3860 isFunctionTemplateSpecialization = true; 3861 // For source fidelity, store all the template param lists. 3862 NewFD->setTemplateParameterListsInfo(Context, 3863 TemplateParamLists.size(), 3864 TemplateParamLists.release()); 3865 3866 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3867 if (isFriend) { 3868 // We want to remove the "template<>", found here. 3869 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3870 3871 // If we remove the template<> and the name is not a 3872 // template-id, we're actually silently creating a problem: 3873 // the friend declaration will refer to an untemplated decl, 3874 // and clearly the user wants a template specialization. So 3875 // we need to insert '<>' after the name. 3876 SourceLocation InsertLoc; 3877 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3878 InsertLoc = D.getName().getSourceRange().getEnd(); 3879 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3880 } 3881 3882 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3883 << Name << RemoveRange 3884 << FixItHint::CreateRemoval(RemoveRange) 3885 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3886 } 3887 } 3888 } 3889 else { 3890 // All template param lists were matched against the scope specifier: 3891 // this is NOT (an explicit specialization of) a template. 3892 if (TemplateParamLists.size() > 0) 3893 // For source fidelity, store all the template param lists. 3894 NewFD->setTemplateParameterListsInfo(Context, 3895 TemplateParamLists.size(), 3896 TemplateParamLists.release()); 3897 } 3898 3899 if (Invalid) { 3900 NewFD->setInvalidDecl(); 3901 if (FunctionTemplate) 3902 FunctionTemplate->setInvalidDecl(); 3903 } 3904 3905 // C++ [dcl.fct.spec]p5: 3906 // The virtual specifier shall only be used in declarations of 3907 // nonstatic class member functions that appear within a 3908 // member-specification of a class declaration; see 10.3. 3909 // 3910 if (isVirtual && !NewFD->isInvalidDecl()) { 3911 if (!isVirtualOkay) { 3912 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3913 diag::err_virtual_non_function); 3914 } else if (!CurContext->isRecord()) { 3915 // 'virtual' was specified outside of the class. 3916 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3917 diag::err_virtual_out_of_class) 3918 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3919 } else if (NewFD->getDescribedFunctionTemplate()) { 3920 // C++ [temp.mem]p3: 3921 // A member function template shall not be virtual. 3922 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3923 diag::err_virtual_member_function_template) 3924 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3925 } else { 3926 // Okay: Add virtual to the method. 3927 NewFD->setVirtualAsWritten(true); 3928 } 3929 } 3930 3931 // C++ [dcl.fct.spec]p3: 3932 // The inline specifier shall not appear on a block scope function declaration. 3933 if (isInline && !NewFD->isInvalidDecl()) { 3934 if (CurContext->isFunctionOrMethod()) { 3935 // 'inline' is not allowed on block scope function declaration. 3936 Diag(D.getDeclSpec().getInlineSpecLoc(), 3937 diag::err_inline_declaration_block_scope) << Name 3938 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3939 } 3940 } 3941 3942 // C++ [dcl.fct.spec]p6: 3943 // The explicit specifier shall be used only in the declaration of a 3944 // constructor or conversion function within its class definition; see 12.3.1 3945 // and 12.3.2. 3946 if (isExplicit && !NewFD->isInvalidDecl()) { 3947 if (!CurContext->isRecord()) { 3948 // 'explicit' was specified outside of the class. 3949 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3950 diag::err_explicit_out_of_class) 3951 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3952 } else if (!isa<CXXConstructorDecl>(NewFD) && 3953 !isa<CXXConversionDecl>(NewFD)) { 3954 // 'explicit' was specified on a function that wasn't a constructor 3955 // or conversion function. 3956 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3957 diag::err_explicit_non_ctor_or_conv_function) 3958 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3959 } 3960 } 3961 3962 // Filter out previous declarations that don't match the scope. 3963 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage(), 3964 isExplicitSpecialization || 3965 isFunctionTemplateSpecialization); 3966 3967 if (isFriend) { 3968 // For now, claim that the objects have no previous declaration. 3969 if (FunctionTemplate) { 3970 FunctionTemplate->setObjectOfFriendDecl(false); 3971 FunctionTemplate->setAccess(AS_public); 3972 } 3973 NewFD->setObjectOfFriendDecl(false); 3974 NewFD->setAccess(AS_public); 3975 } 3976 3977 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 3978 // A method is implicitly inline if it's defined in its class 3979 // definition. 3980 NewFD->setImplicitlyInline(); 3981 } 3982 3983 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3984 !CurContext->isRecord()) { 3985 // C++ [class.static]p1: 3986 // A data or function member of a class may be declared static 3987 // in a class definition, in which case it is a static member of 3988 // the class. 3989 3990 // Complain about the 'static' specifier if it's on an out-of-line 3991 // member function definition. 3992 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3993 diag::err_static_out_of_line) 3994 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3995 } 3996 } 3997 3998 // Handle GNU asm-label extension (encoded as an attribute). 3999 if (Expr *E = (Expr*) D.getAsmLabel()) { 4000 // The parser guarantees this is a string. 4001 StringLiteral *SE = cast<StringLiteral>(E); 4002 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 4003 SE->getString())); 4004 } 4005 4006 // Copy the parameter declarations from the declarator D to the function 4007 // declaration NewFD, if they are available. First scavenge them into Params. 4008 llvm::SmallVector<ParmVarDecl*, 16> Params; 4009 if (D.isFunctionDeclarator()) { 4010 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 4011 4012 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 4013 // function that takes no arguments, not a function that takes a 4014 // single void argument. 4015 // We let through "const void" here because Sema::GetTypeForDeclarator 4016 // already checks for that case. 4017 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4018 FTI.ArgInfo[0].Param && 4019 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 4020 // Empty arg list, don't push any params. 4021 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 4022 4023 // In C++, the empty parameter-type-list must be spelled "void"; a 4024 // typedef of void is not permitted. 4025 if (getLangOptions().CPlusPlus && 4026 Param->getType().getUnqualifiedType() != Context.VoidTy) 4027 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 4028 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 4029 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 4030 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 4031 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 4032 Param->setDeclContext(NewFD); 4033 Params.push_back(Param); 4034 4035 if (Param->isInvalidDecl()) 4036 NewFD->setInvalidDecl(); 4037 } 4038 } 4039 4040 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 4041 // When we're declaring a function with a typedef, typeof, etc as in the 4042 // following example, we'll need to synthesize (unnamed) 4043 // parameters for use in the declaration. 4044 // 4045 // @code 4046 // typedef void fn(int); 4047 // fn f; 4048 // @endcode 4049 4050 // Synthesize a parameter for each argument type. 4051 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 4052 AE = FT->arg_type_end(); AI != AE; ++AI) { 4053 ParmVarDecl *Param = 4054 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 4055 Params.push_back(Param); 4056 } 4057 } else { 4058 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 4059 "Should not need args for typedef of non-prototype fn"); 4060 } 4061 // Finally, we know we have the right number of parameters, install them. 4062 NewFD->setParams(Params.data(), Params.size()); 4063 4064 // Process the non-inheritable attributes on this declaration. 4065 ProcessDeclAttributes(S, NewFD, D, 4066 /*NonInheritable=*/true, /*Inheritable=*/false); 4067 4068 if (!getLangOptions().CPlusPlus) { 4069 // Perform semantic checking on the function declaration. 4070 bool isExplctSpecialization=false; 4071 CheckFunctionDeclaration(S, NewFD, Previous, isExplctSpecialization, 4072 Redeclaration); 4073 assert((NewFD->isInvalidDecl() || !Redeclaration || 4074 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4075 "previous declaration set still overloaded"); 4076 } else { 4077 // If the declarator is a template-id, translate the parser's template 4078 // argument list into our AST format. 4079 bool HasExplicitTemplateArgs = false; 4080 TemplateArgumentListInfo TemplateArgs; 4081 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4082 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4083 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4084 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4085 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4086 TemplateId->getTemplateArgs(), 4087 TemplateId->NumArgs); 4088 translateTemplateArguments(TemplateArgsPtr, 4089 TemplateArgs); 4090 TemplateArgsPtr.release(); 4091 4092 HasExplicitTemplateArgs = true; 4093 4094 if (FunctionTemplate) { 4095 // Function template with explicit template arguments. 4096 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4097 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4098 4099 HasExplicitTemplateArgs = false; 4100 } else if (!isFunctionTemplateSpecialization && 4101 !D.getDeclSpec().isFriendSpecified()) { 4102 // We have encountered something that the user meant to be a 4103 // specialization (because it has explicitly-specified template 4104 // arguments) but that was not introduced with a "template<>" (or had 4105 // too few of them). 4106 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4107 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4108 << FixItHint::CreateInsertion( 4109 D.getDeclSpec().getSourceRange().getBegin(), 4110 "template<> "); 4111 isFunctionTemplateSpecialization = true; 4112 } else { 4113 // "friend void foo<>(int);" is an implicit specialization decl. 4114 isFunctionTemplateSpecialization = true; 4115 } 4116 } else if (isFriend && isFunctionTemplateSpecialization) { 4117 // This combination is only possible in a recovery case; the user 4118 // wrote something like: 4119 // template <> friend void foo(int); 4120 // which we're recovering from as if the user had written: 4121 // friend void foo<>(int); 4122 // Go ahead and fake up a template id. 4123 HasExplicitTemplateArgs = true; 4124 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4125 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4126 } 4127 4128 // If it's a friend (and only if it's a friend), it's possible 4129 // that either the specialized function type or the specialized 4130 // template is dependent, and therefore matching will fail. In 4131 // this case, don't check the specialization yet. 4132 if (isFunctionTemplateSpecialization && isFriend && 4133 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4134 assert(HasExplicitTemplateArgs && 4135 "friend function specialization without template args"); 4136 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4137 Previous)) 4138 NewFD->setInvalidDecl(); 4139 } else if (isFunctionTemplateSpecialization) { 4140 if (CurContext->isDependentContext() && CurContext->isRecord() 4141 && !isFriend) { 4142 Diag(NewFD->getLocation(), diag::err_function_specialization_in_class) 4143 << NewFD->getDeclName(); 4144 NewFD->setInvalidDecl(); 4145 return 0; 4146 } else if (CheckFunctionTemplateSpecialization(NewFD, 4147 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4148 Previous)) 4149 NewFD->setInvalidDecl(); 4150 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4151 if (CheckMemberSpecialization(NewFD, Previous)) 4152 NewFD->setInvalidDecl(); 4153 } 4154 4155 // Perform semantic checking on the function declaration. 4156 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4157 Redeclaration); 4158 4159 assert((NewFD->isInvalidDecl() || !Redeclaration || 4160 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4161 "previous declaration set still overloaded"); 4162 4163 NamedDecl *PrincipalDecl = (FunctionTemplate 4164 ? cast<NamedDecl>(FunctionTemplate) 4165 : NewFD); 4166 4167 if (isFriend && Redeclaration) { 4168 AccessSpecifier Access = AS_public; 4169 if (!NewFD->isInvalidDecl()) 4170 Access = NewFD->getPreviousDeclaration()->getAccess(); 4171 4172 NewFD->setAccess(Access); 4173 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4174 4175 PrincipalDecl->setObjectOfFriendDecl(true); 4176 } 4177 4178 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4179 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4180 PrincipalDecl->setNonMemberOperator(); 4181 4182 // If we have a function template, check the template parameter 4183 // list. This will check and merge default template arguments. 4184 if (FunctionTemplate) { 4185 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4186 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4187 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4188 D.getDeclSpec().isFriendSpecified() 4189 ? (IsFunctionDefinition 4190 ? TPC_FriendFunctionTemplateDefinition 4191 : TPC_FriendFunctionTemplate) 4192 : (D.getCXXScopeSpec().isSet() && 4193 DC && DC->isRecord() && 4194 DC->isDependentContext()) 4195 ? TPC_ClassTemplateMember 4196 : TPC_FunctionTemplate); 4197 } 4198 4199 if (NewFD->isInvalidDecl()) { 4200 // Ignore all the rest of this. 4201 } else if (!Redeclaration) { 4202 // Fake up an access specifier if it's supposed to be a class member. 4203 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4204 NewFD->setAccess(AS_public); 4205 4206 // Qualified decls generally require a previous declaration. 4207 if (D.getCXXScopeSpec().isSet()) { 4208 // ...with the major exception of templated-scope or 4209 // dependent-scope friend declarations. 4210 4211 // TODO: we currently also suppress this check in dependent 4212 // contexts because (1) the parameter depth will be off when 4213 // matching friend templates and (2) we might actually be 4214 // selecting a friend based on a dependent factor. But there 4215 // are situations where these conditions don't apply and we 4216 // can actually do this check immediately. 4217 if (isFriend && 4218 (TemplateParamLists.size() || 4219 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4220 CurContext->isDependentContext())) { 4221 // ignore these 4222 } else { 4223 // The user tried to provide an out-of-line definition for a 4224 // function that is a member of a class or namespace, but there 4225 // was no such member function declared (C++ [class.mfct]p2, 4226 // C++ [namespace.memdef]p2). For example: 4227 // 4228 // class X { 4229 // void f() const; 4230 // }; 4231 // 4232 // void X::f() { } // ill-formed 4233 // 4234 // Complain about this problem, and attempt to suggest close 4235 // matches (e.g., those that differ only in cv-qualifiers and 4236 // whether the parameter types are references). 4237 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4238 << Name << DC << D.getCXXScopeSpec().getRange(); 4239 NewFD->setInvalidDecl(); 4240 4241 DiagnoseInvalidRedeclaration(*this, NewFD); 4242 } 4243 4244 // Unqualified local friend declarations are required to resolve 4245 // to something. 4246 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4247 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4248 NewFD->setInvalidDecl(); 4249 DiagnoseInvalidRedeclaration(*this, NewFD); 4250 } 4251 4252 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4253 !isFriend && !isFunctionTemplateSpecialization && 4254 !isExplicitSpecialization) { 4255 // An out-of-line member function declaration must also be a 4256 // definition (C++ [dcl.meaning]p1). 4257 // Note that this is not the case for explicit specializations of 4258 // function templates or member functions of class templates, per 4259 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4260 // for compatibility with old SWIG code which likes to generate them. 4261 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4262 << D.getCXXScopeSpec().getRange(); 4263 } 4264 } 4265 4266 4267 // Handle attributes. We need to have merged decls when handling attributes 4268 // (for example to check for conflicts, etc). 4269 // FIXME: This needs to happen before we merge declarations. Then, 4270 // let attribute merging cope with attribute conflicts. 4271 ProcessDeclAttributes(S, NewFD, D, 4272 /*NonInheritable=*/false, /*Inheritable=*/true); 4273 4274 // attributes declared post-definition are currently ignored 4275 // FIXME: This should happen during attribute merging 4276 if (Redeclaration && Previous.isSingleResult()) { 4277 const FunctionDecl *Def; 4278 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4279 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 4280 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4281 Diag(Def->getLocation(), diag::note_previous_definition); 4282 } 4283 } 4284 4285 AddKnownFunctionAttributes(NewFD); 4286 4287 if (NewFD->hasAttr<OverloadableAttr>() && 4288 !NewFD->getType()->getAs<FunctionProtoType>()) { 4289 Diag(NewFD->getLocation(), 4290 diag::err_attribute_overloadable_no_prototype) 4291 << NewFD; 4292 4293 // Turn this into a variadic function with no parameters. 4294 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4295 FunctionProtoType::ExtProtoInfo EPI; 4296 EPI.Variadic = true; 4297 EPI.ExtInfo = FT->getExtInfo(); 4298 4299 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4300 NewFD->setType(R); 4301 } 4302 4303 // If there's a #pragma GCC visibility in scope, and this isn't a class 4304 // member, set the visibility of this function. 4305 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4306 AddPushedVisibilityAttribute(NewFD); 4307 4308 // If this is a locally-scoped extern C function, update the 4309 // map of such names. 4310 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4311 && !NewFD->isInvalidDecl()) 4312 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4313 4314 // Set this FunctionDecl's range up to the right paren. 4315 NewFD->setRangeEnd(D.getSourceRange().getEnd()); 4316 4317 if (getLangOptions().CPlusPlus) { 4318 if (FunctionTemplate) { 4319 if (NewFD->isInvalidDecl()) 4320 FunctionTemplate->setInvalidDecl(); 4321 return FunctionTemplate; 4322 } 4323 } 4324 4325 MarkUnusedFileScopedDecl(NewFD); 4326 4327 if (getLangOptions().CUDA) 4328 if (IdentifierInfo *II = NewFD->getIdentifier()) 4329 if (!NewFD->isInvalidDecl() && 4330 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4331 if (II->isStr("cudaConfigureCall")) { 4332 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4333 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4334 4335 Context.setcudaConfigureCallDecl(NewFD); 4336 } 4337 } 4338 4339 return NewFD; 4340} 4341 4342/// \brief Perform semantic checking of a new function declaration. 4343/// 4344/// Performs semantic analysis of the new function declaration 4345/// NewFD. This routine performs all semantic checking that does not 4346/// require the actual declarator involved in the declaration, and is 4347/// used both for the declaration of functions as they are parsed 4348/// (called via ActOnDeclarator) and for the declaration of functions 4349/// that have been instantiated via C++ template instantiation (called 4350/// via InstantiateDecl). 4351/// 4352/// \param IsExplicitSpecialiation whether this new function declaration is 4353/// an explicit specialization of the previous declaration. 4354/// 4355/// This sets NewFD->isInvalidDecl() to true if there was an error. 4356void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4357 LookupResult &Previous, 4358 bool IsExplicitSpecialization, 4359 bool &Redeclaration) { 4360 // If NewFD is already known erroneous, don't do any of this checking. 4361 if (NewFD->isInvalidDecl()) { 4362 // If this is a class member, mark the class invalid immediately. 4363 // This avoids some consistency errors later. 4364 if (isa<CXXMethodDecl>(NewFD)) 4365 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4366 4367 return; 4368 } 4369 4370 if (NewFD->getResultType()->isVariablyModifiedType()) { 4371 // Functions returning a variably modified type violate C99 6.7.5.2p2 4372 // because all functions have linkage. 4373 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4374 return NewFD->setInvalidDecl(); 4375 } 4376 4377 if (NewFD->isMain()) 4378 CheckMain(NewFD); 4379 4380 // Check for a previous declaration of this name. 4381 if (Previous.empty() && NewFD->isExternC()) { 4382 // Since we did not find anything by this name and we're declaring 4383 // an extern "C" function, look for a non-visible extern "C" 4384 // declaration with the same name. 4385 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4386 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4387 if (Pos != LocallyScopedExternalDecls.end()) 4388 Previous.addDecl(Pos->second); 4389 } 4390 4391 // Merge or overload the declaration with an existing declaration of 4392 // the same name, if appropriate. 4393 if (!Previous.empty()) { 4394 // Determine whether NewFD is an overload of PrevDecl or 4395 // a declaration that requires merging. If it's an overload, 4396 // there's no more work to do here; we'll just add the new 4397 // function to the scope. 4398 4399 NamedDecl *OldDecl = 0; 4400 if (!AllowOverloadingOfFunction(Previous, Context)) { 4401 Redeclaration = true; 4402 OldDecl = Previous.getFoundDecl(); 4403 } else { 4404 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4405 /*NewIsUsingDecl*/ false)) { 4406 case Ovl_Match: 4407 Redeclaration = true; 4408 break; 4409 4410 case Ovl_NonFunction: 4411 Redeclaration = true; 4412 break; 4413 4414 case Ovl_Overload: 4415 Redeclaration = false; 4416 break; 4417 } 4418 4419 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4420 // If a function name is overloadable in C, then every function 4421 // with that name must be marked "overloadable". 4422 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4423 << Redeclaration << NewFD; 4424 NamedDecl *OverloadedDecl = 0; 4425 if (Redeclaration) 4426 OverloadedDecl = OldDecl; 4427 else if (!Previous.empty()) 4428 OverloadedDecl = Previous.getRepresentativeDecl(); 4429 if (OverloadedDecl) 4430 Diag(OverloadedDecl->getLocation(), 4431 diag::note_attribute_overloadable_prev_overload); 4432 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4433 Context)); 4434 } 4435 } 4436 4437 if (Redeclaration) { 4438 // NewFD and OldDecl represent declarations that need to be 4439 // merged. 4440 if (MergeFunctionDecl(NewFD, OldDecl)) 4441 return NewFD->setInvalidDecl(); 4442 4443 Previous.clear(); 4444 Previous.addDecl(OldDecl); 4445 4446 if (FunctionTemplateDecl *OldTemplateDecl 4447 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4448 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4449 FunctionTemplateDecl *NewTemplateDecl 4450 = NewFD->getDescribedFunctionTemplate(); 4451 assert(NewTemplateDecl && "Template/non-template mismatch"); 4452 if (CXXMethodDecl *Method 4453 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4454 Method->setAccess(OldTemplateDecl->getAccess()); 4455 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4456 } 4457 4458 // If this is an explicit specialization of a member that is a function 4459 // template, mark it as a member specialization. 4460 if (IsExplicitSpecialization && 4461 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4462 NewTemplateDecl->setMemberSpecialization(); 4463 assert(OldTemplateDecl->isMemberSpecialization()); 4464 } 4465 } else { 4466 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4467 NewFD->setAccess(OldDecl->getAccess()); 4468 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4469 } 4470 } 4471 } 4472 4473 // Semantic checking for this function declaration (in isolation). 4474 if (getLangOptions().CPlusPlus) { 4475 // C++-specific checks. 4476 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4477 CheckConstructor(Constructor); 4478 } else if (CXXDestructorDecl *Destructor = 4479 dyn_cast<CXXDestructorDecl>(NewFD)) { 4480 CXXRecordDecl *Record = Destructor->getParent(); 4481 QualType ClassType = Context.getTypeDeclType(Record); 4482 4483 // FIXME: Shouldn't we be able to perform this check even when the class 4484 // type is dependent? Both gcc and edg can handle that. 4485 if (!ClassType->isDependentType()) { 4486 DeclarationName Name 4487 = Context.DeclarationNames.getCXXDestructorName( 4488 Context.getCanonicalType(ClassType)); 4489 if (NewFD->getDeclName() != Name) { 4490 Diag(NewFD->getLocation(), diag::err_destructor_name); 4491 return NewFD->setInvalidDecl(); 4492 } 4493 } 4494 } else if (CXXConversionDecl *Conversion 4495 = dyn_cast<CXXConversionDecl>(NewFD)) { 4496 ActOnConversionDeclarator(Conversion); 4497 } 4498 4499 // Find any virtual functions that this function overrides. 4500 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4501 if (!Method->isFunctionTemplateSpecialization() && 4502 !Method->getDescribedFunctionTemplate()) { 4503 if (AddOverriddenMethods(Method->getParent(), Method)) { 4504 // If the function was marked as "static", we have a problem. 4505 if (NewFD->getStorageClass() == SC_Static) { 4506 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4507 << NewFD->getDeclName(); 4508 for (CXXMethodDecl::method_iterator 4509 Overridden = Method->begin_overridden_methods(), 4510 OverriddenEnd = Method->end_overridden_methods(); 4511 Overridden != OverriddenEnd; 4512 ++Overridden) { 4513 Diag((*Overridden)->getLocation(), 4514 diag::note_overridden_virtual_function); 4515 } 4516 } 4517 } 4518 } 4519 } 4520 4521 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4522 if (NewFD->isOverloadedOperator() && 4523 CheckOverloadedOperatorDeclaration(NewFD)) 4524 return NewFD->setInvalidDecl(); 4525 4526 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4527 if (NewFD->getLiteralIdentifier() && 4528 CheckLiteralOperatorDeclaration(NewFD)) 4529 return NewFD->setInvalidDecl(); 4530 4531 // In C++, check default arguments now that we have merged decls. Unless 4532 // the lexical context is the class, because in this case this is done 4533 // during delayed parsing anyway. 4534 if (!CurContext->isRecord()) 4535 CheckCXXDefaultArguments(NewFD); 4536 4537 // If this function declares a builtin function, check the type of this 4538 // declaration against the expected type for the builtin. 4539 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 4540 ASTContext::GetBuiltinTypeError Error; 4541 QualType T = Context.GetBuiltinType(BuiltinID, Error); 4542 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 4543 // The type of this function differs from the type of the builtin, 4544 // so forget about the builtin entirely. 4545 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 4546 } 4547 } 4548 } 4549} 4550 4551void Sema::CheckMain(FunctionDecl* FD) { 4552 // C++ [basic.start.main]p3: A program that declares main to be inline 4553 // or static is ill-formed. 4554 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4555 // shall not appear in a declaration of main. 4556 // static main is not an error under C99, but we should warn about it. 4557 bool isInline = FD->isInlineSpecified(); 4558 bool isStatic = FD->getStorageClass() == SC_Static; 4559 if (isInline || isStatic) { 4560 unsigned diagID = diag::warn_unusual_main_decl; 4561 if (isInline || getLangOptions().CPlusPlus) 4562 diagID = diag::err_unusual_main_decl; 4563 4564 int which = isStatic + (isInline << 1) - 1; 4565 Diag(FD->getLocation(), diagID) << which; 4566 } 4567 4568 QualType T = FD->getType(); 4569 assert(T->isFunctionType() && "function decl is not of function type"); 4570 const FunctionType* FT = T->getAs<FunctionType>(); 4571 4572 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4573 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 4574 FD->setInvalidDecl(true); 4575 } 4576 4577 // Treat protoless main() as nullary. 4578 if (isa<FunctionNoProtoType>(FT)) return; 4579 4580 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4581 unsigned nparams = FTP->getNumArgs(); 4582 assert(FD->getNumParams() == nparams); 4583 4584 bool HasExtraParameters = (nparams > 3); 4585 4586 // Darwin passes an undocumented fourth argument of type char**. If 4587 // other platforms start sprouting these, the logic below will start 4588 // getting shifty. 4589 if (nparams == 4 && 4590 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4591 HasExtraParameters = false; 4592 4593 if (HasExtraParameters) { 4594 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4595 FD->setInvalidDecl(true); 4596 nparams = 3; 4597 } 4598 4599 // FIXME: a lot of the following diagnostics would be improved 4600 // if we had some location information about types. 4601 4602 QualType CharPP = 4603 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4604 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4605 4606 for (unsigned i = 0; i < nparams; ++i) { 4607 QualType AT = FTP->getArgType(i); 4608 4609 bool mismatch = true; 4610 4611 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4612 mismatch = false; 4613 else if (Expected[i] == CharPP) { 4614 // As an extension, the following forms are okay: 4615 // char const ** 4616 // char const * const * 4617 // char * const * 4618 4619 QualifierCollector qs; 4620 const PointerType* PT; 4621 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4622 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4623 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4624 qs.removeConst(); 4625 mismatch = !qs.empty(); 4626 } 4627 } 4628 4629 if (mismatch) { 4630 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4631 // TODO: suggest replacing given type with expected type 4632 FD->setInvalidDecl(true); 4633 } 4634 } 4635 4636 if (nparams == 1 && !FD->isInvalidDecl()) { 4637 Diag(FD->getLocation(), diag::warn_main_one_arg); 4638 } 4639 4640 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 4641 Diag(FD->getLocation(), diag::err_main_template_decl); 4642 FD->setInvalidDecl(); 4643 } 4644} 4645 4646bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4647 // FIXME: Need strict checking. In C89, we need to check for 4648 // any assignment, increment, decrement, function-calls, or 4649 // commas outside of a sizeof. In C99, it's the same list, 4650 // except that the aforementioned are allowed in unevaluated 4651 // expressions. Everything else falls under the 4652 // "may accept other forms of constant expressions" exception. 4653 // (We never end up here for C++, so the constant expression 4654 // rules there don't matter.) 4655 if (Init->isConstantInitializer(Context, false)) 4656 return false; 4657 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4658 << Init->getSourceRange(); 4659 return true; 4660} 4661 4662/// AddInitializerToDecl - Adds the initializer Init to the 4663/// declaration dcl. If DirectInit is true, this is C++ direct 4664/// initialization rather than copy initialization. 4665void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 4666 bool DirectInit, bool TypeMayContainAuto) { 4667 // If there is no declaration, there was an error parsing it. Just ignore 4668 // the initializer. 4669 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 4670 return; 4671 4672 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4673 // With declarators parsed the way they are, the parser cannot 4674 // distinguish between a normal initializer and a pure-specifier. 4675 // Thus this grotesque test. 4676 IntegerLiteral *IL; 4677 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4678 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4679 CheckPureMethod(Method, Init->getSourceRange()); 4680 else { 4681 Diag(Method->getLocation(), diag::err_member_function_initialization) 4682 << Method->getDeclName() << Init->getSourceRange(); 4683 Method->setInvalidDecl(); 4684 } 4685 return; 4686 } 4687 4688 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4689 if (!VDecl) { 4690 if (getLangOptions().CPlusPlus && 4691 RealDecl->getLexicalDeclContext()->isRecord() && 4692 isa<NamedDecl>(RealDecl)) 4693 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4694 else 4695 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4696 RealDecl->setInvalidDecl(); 4697 return; 4698 } 4699 4700 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 4701 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 4702 TypeSourceInfo *DeducedType = 0; 4703 if (!DeduceAutoType(VDecl->getTypeSourceInfo(), Init, DeducedType)) 4704 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 4705 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 4706 << Init->getSourceRange(); 4707 if (!DeducedType) { 4708 RealDecl->setInvalidDecl(); 4709 return; 4710 } 4711 VDecl->setTypeSourceInfo(DeducedType); 4712 VDecl->setType(DeducedType->getType()); 4713 4714 // If this is a redeclaration, check that the type we just deduced matches 4715 // the previously declared type. 4716 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 4717 MergeVarDeclTypes(VDecl, Old); 4718 } 4719 4720 4721 // A definition must end up with a complete type, which means it must be 4722 // complete with the restriction that an array type might be completed by the 4723 // initializer; note that later code assumes this restriction. 4724 QualType BaseDeclType = VDecl->getType(); 4725 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4726 BaseDeclType = Array->getElementType(); 4727 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4728 diag::err_typecheck_decl_incomplete_type)) { 4729 RealDecl->setInvalidDecl(); 4730 return; 4731 } 4732 4733 // The variable can not have an abstract class type. 4734 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4735 diag::err_abstract_type_in_decl, 4736 AbstractVariableType)) 4737 VDecl->setInvalidDecl(); 4738 4739 const VarDecl *Def; 4740 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4741 Diag(VDecl->getLocation(), diag::err_redefinition) 4742 << VDecl->getDeclName(); 4743 Diag(Def->getLocation(), diag::note_previous_definition); 4744 VDecl->setInvalidDecl(); 4745 return; 4746 } 4747 4748 const VarDecl* PrevInit = 0; 4749 if (getLangOptions().CPlusPlus) { 4750 // C++ [class.static.data]p4 4751 // If a static data member is of const integral or const 4752 // enumeration type, its declaration in the class definition can 4753 // specify a constant-initializer which shall be an integral 4754 // constant expression (5.19). In that case, the member can appear 4755 // in integral constant expressions. The member shall still be 4756 // defined in a namespace scope if it is used in the program and the 4757 // namespace scope definition shall not contain an initializer. 4758 // 4759 // We already performed a redefinition check above, but for static 4760 // data members we also need to check whether there was an in-class 4761 // declaration with an initializer. 4762 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4763 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4764 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4765 return; 4766 } 4767 4768 if (VDecl->hasLocalStorage()) 4769 getCurFunction()->setHasBranchProtectedScope(); 4770 4771 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 4772 VDecl->setInvalidDecl(); 4773 return; 4774 } 4775 } 4776 4777 // Capture the variable that is being initialized and the style of 4778 // initialization. 4779 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4780 4781 // FIXME: Poor source location information. 4782 InitializationKind Kind 4783 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4784 Init->getLocStart(), 4785 Init->getLocEnd()) 4786 : InitializationKind::CreateCopy(VDecl->getLocation(), 4787 Init->getLocStart()); 4788 4789 // Get the decls type and save a reference for later, since 4790 // CheckInitializerTypes may change it. 4791 QualType DclT = VDecl->getType(), SavT = DclT; 4792 if (VDecl->isLocalVarDecl()) { 4793 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4794 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4795 VDecl->setInvalidDecl(); 4796 } else if (!VDecl->isInvalidDecl()) { 4797 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4798 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4799 MultiExprArg(*this, &Init, 1), 4800 &DclT); 4801 if (Result.isInvalid()) { 4802 VDecl->setInvalidDecl(); 4803 return; 4804 } 4805 4806 Init = Result.takeAs<Expr>(); 4807 4808 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4809 // Don't check invalid declarations to avoid emitting useless diagnostics. 4810 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4811 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4812 CheckForConstantInitializer(Init, DclT); 4813 } 4814 } 4815 } else if (VDecl->isStaticDataMember() && 4816 VDecl->getLexicalDeclContext()->isRecord()) { 4817 // This is an in-class initialization for a static data member, e.g., 4818 // 4819 // struct S { 4820 // static const int value = 17; 4821 // }; 4822 4823 // Try to perform the initialization regardless. 4824 if (!VDecl->isInvalidDecl()) { 4825 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4826 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4827 MultiExprArg(*this, &Init, 1), 4828 &DclT); 4829 if (Result.isInvalid()) { 4830 VDecl->setInvalidDecl(); 4831 return; 4832 } 4833 4834 Init = Result.takeAs<Expr>(); 4835 } 4836 4837 // C++ [class.mem]p4: 4838 // A member-declarator can contain a constant-initializer only 4839 // if it declares a static member (9.4) of const integral or 4840 // const enumeration type, see 9.4.2. 4841 QualType T = VDecl->getType(); 4842 4843 // Do nothing on dependent types. 4844 if (T->isDependentType()) { 4845 4846 // Require constness. 4847 } else if (!T.isConstQualified()) { 4848 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4849 << Init->getSourceRange(); 4850 VDecl->setInvalidDecl(); 4851 4852 // We allow integer constant expressions in all cases. 4853 } else if (T->isIntegralOrEnumerationType()) { 4854 if (!Init->isValueDependent()) { 4855 // Check whether the expression is a constant expression. 4856 llvm::APSInt Value; 4857 SourceLocation Loc; 4858 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4859 Diag(Loc, diag::err_in_class_initializer_non_constant) 4860 << Init->getSourceRange(); 4861 VDecl->setInvalidDecl(); 4862 } 4863 } 4864 4865 // We allow floating-point constants as an extension in C++03, and 4866 // C++0x has far more complicated rules that we don't really 4867 // implement fully. 4868 } else { 4869 bool Allowed = false; 4870 if (getLangOptions().CPlusPlus0x) { 4871 Allowed = T->isLiteralType(); 4872 } else if (T->isFloatingType()) { // also permits complex, which is ok 4873 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4874 << T << Init->getSourceRange(); 4875 Allowed = true; 4876 } 4877 4878 if (!Allowed) { 4879 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4880 << T << Init->getSourceRange(); 4881 VDecl->setInvalidDecl(); 4882 4883 // TODO: there are probably expressions that pass here that shouldn't. 4884 } else if (!Init->isValueDependent() && 4885 !Init->isConstantInitializer(Context, false)) { 4886 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4887 << Init->getSourceRange(); 4888 VDecl->setInvalidDecl(); 4889 } 4890 } 4891 } else if (VDecl->isFileVarDecl()) { 4892 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4893 (!getLangOptions().CPlusPlus || 4894 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4895 Diag(VDecl->getLocation(), diag::warn_extern_init); 4896 if (!VDecl->isInvalidDecl()) { 4897 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4898 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4899 MultiExprArg(*this, &Init, 1), 4900 &DclT); 4901 if (Result.isInvalid()) { 4902 VDecl->setInvalidDecl(); 4903 return; 4904 } 4905 4906 Init = Result.takeAs<Expr>(); 4907 } 4908 4909 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4910 // Don't check invalid declarations to avoid emitting useless diagnostics. 4911 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4912 // C99 6.7.8p4. All file scoped initializers need to be constant. 4913 CheckForConstantInitializer(Init, DclT); 4914 } 4915 } 4916 // If the type changed, it means we had an incomplete type that was 4917 // completed by the initializer. For example: 4918 // int ary[] = { 1, 3, 5 }; 4919 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4920 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4921 VDecl->setType(DclT); 4922 Init->setType(DclT); 4923 } 4924 4925 4926 // If this variable is a local declaration with record type, make sure it 4927 // doesn't have a flexible member initialization. We only support this as a 4928 // global/static definition. 4929 if (VDecl->hasLocalStorage()) 4930 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4931 if (RT->getDecl()->hasFlexibleArrayMember()) { 4932 // Check whether the initializer tries to initialize the flexible 4933 // array member itself to anything other than an empty initializer list. 4934 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 4935 unsigned Index = std::distance(RT->getDecl()->field_begin(), 4936 RT->getDecl()->field_end()) - 1; 4937 if (Index < ILE->getNumInits() && 4938 !(isa<InitListExpr>(ILE->getInit(Index)) && 4939 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 4940 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4941 VDecl->setInvalidDecl(); 4942 } 4943 } 4944 } 4945 4946 // Check any implicit conversions within the expression. 4947 CheckImplicitConversions(Init, VDecl->getLocation()); 4948 4949 Init = MaybeCreateExprWithCleanups(Init); 4950 // Attach the initializer to the decl. 4951 VDecl->setInit(Init); 4952 4953 CheckCompleteVariableDeclaration(VDecl); 4954} 4955 4956/// ActOnInitializerError - Given that there was an error parsing an 4957/// initializer for the given declaration, try to return to some form 4958/// of sanity. 4959void Sema::ActOnInitializerError(Decl *D) { 4960 // Our main concern here is re-establishing invariants like "a 4961 // variable's type is either dependent or complete". 4962 if (!D || D->isInvalidDecl()) return; 4963 4964 VarDecl *VD = dyn_cast<VarDecl>(D); 4965 if (!VD) return; 4966 4967 // Auto types are meaningless if we can't make sense of the initializer. 4968 if (ParsingInitForAutoVars.count(D)) { 4969 D->setInvalidDecl(); 4970 return; 4971 } 4972 4973 QualType Ty = VD->getType(); 4974 if (Ty->isDependentType()) return; 4975 4976 // Require a complete type. 4977 if (RequireCompleteType(VD->getLocation(), 4978 Context.getBaseElementType(Ty), 4979 diag::err_typecheck_decl_incomplete_type)) { 4980 VD->setInvalidDecl(); 4981 return; 4982 } 4983 4984 // Require an abstract type. 4985 if (RequireNonAbstractType(VD->getLocation(), Ty, 4986 diag::err_abstract_type_in_decl, 4987 AbstractVariableType)) { 4988 VD->setInvalidDecl(); 4989 return; 4990 } 4991 4992 // Don't bother complaining about constructors or destructors, 4993 // though. 4994} 4995 4996void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4997 bool TypeMayContainAuto) { 4998 // If there is no declaration, there was an error parsing it. Just ignore it. 4999 if (RealDecl == 0) 5000 return; 5001 5002 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 5003 QualType Type = Var->getType(); 5004 5005 // C++0x [dcl.spec.auto]p3 5006 if (TypeMayContainAuto && Type->getContainedAutoType()) { 5007 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 5008 << Var->getDeclName() << Type; 5009 Var->setInvalidDecl(); 5010 return; 5011 } 5012 5013 switch (Var->isThisDeclarationADefinition()) { 5014 case VarDecl::Definition: 5015 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 5016 break; 5017 5018 // We have an out-of-line definition of a static data member 5019 // that has an in-class initializer, so we type-check this like 5020 // a declaration. 5021 // 5022 // Fall through 5023 5024 case VarDecl::DeclarationOnly: 5025 // It's only a declaration. 5026 5027 // Block scope. C99 6.7p7: If an identifier for an object is 5028 // declared with no linkage (C99 6.2.2p6), the type for the 5029 // object shall be complete. 5030 if (!Type->isDependentType() && Var->isLocalVarDecl() && 5031 !Var->getLinkage() && !Var->isInvalidDecl() && 5032 RequireCompleteType(Var->getLocation(), Type, 5033 diag::err_typecheck_decl_incomplete_type)) 5034 Var->setInvalidDecl(); 5035 5036 // Make sure that the type is not abstract. 5037 if (!Type->isDependentType() && !Var->isInvalidDecl() && 5038 RequireNonAbstractType(Var->getLocation(), Type, 5039 diag::err_abstract_type_in_decl, 5040 AbstractVariableType)) 5041 Var->setInvalidDecl(); 5042 return; 5043 5044 case VarDecl::TentativeDefinition: 5045 // File scope. C99 6.9.2p2: A declaration of an identifier for an 5046 // object that has file scope without an initializer, and without a 5047 // storage-class specifier or with the storage-class specifier "static", 5048 // constitutes a tentative definition. Note: A tentative definition with 5049 // external linkage is valid (C99 6.2.2p5). 5050 if (!Var->isInvalidDecl()) { 5051 if (const IncompleteArrayType *ArrayT 5052 = Context.getAsIncompleteArrayType(Type)) { 5053 if (RequireCompleteType(Var->getLocation(), 5054 ArrayT->getElementType(), 5055 diag::err_illegal_decl_array_incomplete_type)) 5056 Var->setInvalidDecl(); 5057 } else if (Var->getStorageClass() == SC_Static) { 5058 // C99 6.9.2p3: If the declaration of an identifier for an object is 5059 // a tentative definition and has internal linkage (C99 6.2.2p3), the 5060 // declared type shall not be an incomplete type. 5061 // NOTE: code such as the following 5062 // static struct s; 5063 // struct s { int a; }; 5064 // is accepted by gcc. Hence here we issue a warning instead of 5065 // an error and we do not invalidate the static declaration. 5066 // NOTE: to avoid multiple warnings, only check the first declaration. 5067 if (Var->getPreviousDeclaration() == 0) 5068 RequireCompleteType(Var->getLocation(), Type, 5069 diag::ext_typecheck_decl_incomplete_type); 5070 } 5071 } 5072 5073 // Record the tentative definition; we're done. 5074 if (!Var->isInvalidDecl()) 5075 TentativeDefinitions.push_back(Var); 5076 return; 5077 } 5078 5079 // Provide a specific diagnostic for uninitialized variable 5080 // definitions with incomplete array type. 5081 if (Type->isIncompleteArrayType()) { 5082 Diag(Var->getLocation(), 5083 diag::err_typecheck_incomplete_array_needs_initializer); 5084 Var->setInvalidDecl(); 5085 return; 5086 } 5087 5088 // Provide a specific diagnostic for uninitialized variable 5089 // definitions with reference type. 5090 if (Type->isReferenceType()) { 5091 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5092 << Var->getDeclName() 5093 << SourceRange(Var->getLocation(), Var->getLocation()); 5094 Var->setInvalidDecl(); 5095 return; 5096 } 5097 5098 // Do not attempt to type-check the default initializer for a 5099 // variable with dependent type. 5100 if (Type->isDependentType()) 5101 return; 5102 5103 if (Var->isInvalidDecl()) 5104 return; 5105 5106 if (RequireCompleteType(Var->getLocation(), 5107 Context.getBaseElementType(Type), 5108 diag::err_typecheck_decl_incomplete_type)) { 5109 Var->setInvalidDecl(); 5110 return; 5111 } 5112 5113 // The variable can not have an abstract class type. 5114 if (RequireNonAbstractType(Var->getLocation(), Type, 5115 diag::err_abstract_type_in_decl, 5116 AbstractVariableType)) { 5117 Var->setInvalidDecl(); 5118 return; 5119 } 5120 5121 const RecordType *Record 5122 = Context.getBaseElementType(Type)->getAs<RecordType>(); 5123 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 5124 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 5125 // C++03 [dcl.init]p9: 5126 // If no initializer is specified for an object, and the 5127 // object is of (possibly cv-qualified) non-POD class type (or 5128 // array thereof), the object shall be default-initialized; if 5129 // the object is of const-qualified type, the underlying class 5130 // type shall have a user-declared default 5131 // constructor. Otherwise, if no initializer is specified for 5132 // a non- static object, the object and its subobjects, if 5133 // any, have an indeterminate initial value); if the object 5134 // or any of its subobjects are of const-qualified type, the 5135 // program is ill-formed. 5136 // FIXME: DPG thinks it is very fishy that C++0x disables this. 5137 } else { 5138 // Check for jumps past the implicit initializer. C++0x 5139 // clarifies that this applies to a "variable with automatic 5140 // storage duration", not a "local variable". 5141 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 5142 getCurFunction()->setHasBranchProtectedScope(); 5143 5144 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5145 InitializationKind Kind 5146 = InitializationKind::CreateDefault(Var->getLocation()); 5147 5148 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5149 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5150 MultiExprArg(*this, 0, 0)); 5151 if (Init.isInvalid()) 5152 Var->setInvalidDecl(); 5153 else if (Init.get()) 5154 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5155 } 5156 5157 CheckCompleteVariableDeclaration(Var); 5158 } 5159} 5160 5161void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5162 if (var->isInvalidDecl()) return; 5163 5164 // All the following checks are C++ only. 5165 if (!getLangOptions().CPlusPlus) return; 5166 5167 QualType baseType = Context.getBaseElementType(var->getType()); 5168 if (baseType->isDependentType()) return; 5169 5170 // __block variables might require us to capture a copy-initializer. 5171 if (var->hasAttr<BlocksAttr>()) { 5172 // It's currently invalid to ever have a __block variable with an 5173 // array type; should we diagnose that here? 5174 5175 // Regardless, we don't want to ignore array nesting when 5176 // constructing this copy. 5177 QualType type = var->getType(); 5178 5179 if (type->isStructureOrClassType()) { 5180 SourceLocation poi = var->getLocation(); 5181 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5182 ExprResult result = 5183 PerformCopyInitialization( 5184 InitializedEntity::InitializeBlock(poi, type, false), 5185 poi, Owned(varRef)); 5186 if (!result.isInvalid()) { 5187 result = MaybeCreateExprWithCleanups(result); 5188 Expr *init = result.takeAs<Expr>(); 5189 Context.setBlockVarCopyInits(var, init); 5190 } 5191 } 5192 } 5193 5194 // Check for global constructors. 5195 if (!var->getDeclContext()->isDependentContext() && 5196 var->hasGlobalStorage() && 5197 !var->isStaticLocal() && 5198 var->getInit() && 5199 !var->getInit()->isConstantInitializer(Context, 5200 baseType->isReferenceType())) 5201 Diag(var->getLocation(), diag::warn_global_constructor) 5202 << var->getInit()->getSourceRange(); 5203 5204 // Require the destructor. 5205 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5206 FinalizeVarWithDestructor(var, recordType); 5207} 5208 5209/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5210/// any semantic actions necessary after any initializer has been attached. 5211void 5212Sema::FinalizeDeclaration(Decl *ThisDecl) { 5213 // Note that we are no longer parsing the initializer for this declaration. 5214 ParsingInitForAutoVars.erase(ThisDecl); 5215} 5216 5217Sema::DeclGroupPtrTy 5218Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5219 Decl **Group, unsigned NumDecls) { 5220 llvm::SmallVector<Decl*, 8> Decls; 5221 5222 if (DS.isTypeSpecOwned()) 5223 Decls.push_back(DS.getRepAsDecl()); 5224 5225 for (unsigned i = 0; i != NumDecls; ++i) 5226 if (Decl *D = Group[i]) 5227 Decls.push_back(D); 5228 5229 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5230 DS.getTypeSpecType() == DeclSpec::TST_auto); 5231} 5232 5233/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5234/// group, performing any necessary semantic checking. 5235Sema::DeclGroupPtrTy 5236Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5237 bool TypeMayContainAuto) { 5238 // C++0x [dcl.spec.auto]p7: 5239 // If the type deduced for the template parameter U is not the same in each 5240 // deduction, the program is ill-formed. 5241 // FIXME: When initializer-list support is added, a distinction is needed 5242 // between the deduced type U and the deduced type which 'auto' stands for. 5243 // auto a = 0, b = { 1, 2, 3 }; 5244 // is legal because the deduced type U is 'int' in both cases. 5245 if (TypeMayContainAuto && NumDecls > 1) { 5246 QualType Deduced; 5247 CanQualType DeducedCanon; 5248 VarDecl *DeducedDecl = 0; 5249 for (unsigned i = 0; i != NumDecls; ++i) { 5250 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5251 AutoType *AT = D->getType()->getContainedAutoType(); 5252 // Don't reissue diagnostics when instantiating a template. 5253 if (AT && D->isInvalidDecl()) 5254 break; 5255 if (AT && AT->isDeduced()) { 5256 QualType U = AT->getDeducedType(); 5257 CanQualType UCanon = Context.getCanonicalType(U); 5258 if (Deduced.isNull()) { 5259 Deduced = U; 5260 DeducedCanon = UCanon; 5261 DeducedDecl = D; 5262 } else if (DeducedCanon != UCanon) { 5263 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5264 diag::err_auto_different_deductions) 5265 << Deduced << DeducedDecl->getDeclName() 5266 << U << D->getDeclName() 5267 << DeducedDecl->getInit()->getSourceRange() 5268 << D->getInit()->getSourceRange(); 5269 D->setInvalidDecl(); 5270 break; 5271 } 5272 } 5273 } 5274 } 5275 } 5276 5277 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5278} 5279 5280 5281/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5282/// to introduce parameters into function prototype scope. 5283Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5284 const DeclSpec &DS = D.getDeclSpec(); 5285 5286 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5287 VarDecl::StorageClass StorageClass = SC_None; 5288 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5289 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5290 StorageClass = SC_Register; 5291 StorageClassAsWritten = SC_Register; 5292 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5293 Diag(DS.getStorageClassSpecLoc(), 5294 diag::err_invalid_storage_class_in_func_decl); 5295 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5296 } 5297 5298 if (D.getDeclSpec().isThreadSpecified()) 5299 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5300 5301 DiagnoseFunctionSpecifiers(D); 5302 5303 TagDecl *OwnedDecl = 0; 5304 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 5305 QualType parmDeclType = TInfo->getType(); 5306 5307 if (getLangOptions().CPlusPlus) { 5308 // Check that there are no default arguments inside the type of this 5309 // parameter. 5310 CheckExtraCXXDefaultArguments(D); 5311 5312 if (OwnedDecl && OwnedDecl->isDefinition()) { 5313 // C++ [dcl.fct]p6: 5314 // Types shall not be defined in return or parameter types. 5315 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 5316 << Context.getTypeDeclType(OwnedDecl); 5317 } 5318 5319 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5320 if (D.getCXXScopeSpec().isSet()) { 5321 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5322 << D.getCXXScopeSpec().getRange(); 5323 D.getCXXScopeSpec().clear(); 5324 } 5325 } 5326 5327 // Ensure we have a valid name 5328 IdentifierInfo *II = 0; 5329 if (D.hasName()) { 5330 II = D.getIdentifier(); 5331 if (!II) { 5332 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5333 << GetNameForDeclarator(D).getName().getAsString(); 5334 D.setInvalidType(true); 5335 } 5336 } 5337 5338 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 5339 if (II) { 5340 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 5341 ForRedeclaration); 5342 LookupName(R, S); 5343 if (R.isSingleResult()) { 5344 NamedDecl *PrevDecl = R.getFoundDecl(); 5345 if (PrevDecl->isTemplateParameter()) { 5346 // Maybe we will complain about the shadowed template parameter. 5347 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5348 // Just pretend that we didn't see the previous declaration. 5349 PrevDecl = 0; 5350 } else if (S->isDeclScope(PrevDecl)) { 5351 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 5352 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5353 5354 // Recover by removing the name 5355 II = 0; 5356 D.SetIdentifier(0, D.getIdentifierLoc()); 5357 D.setInvalidType(true); 5358 } 5359 } 5360 } 5361 5362 // Temporarily put parameter variables in the translation unit, not 5363 // the enclosing context. This prevents them from accidentally 5364 // looking like class members in C++. 5365 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 5366 D.getSourceRange().getBegin(), 5367 D.getIdentifierLoc(), II, 5368 parmDeclType, TInfo, 5369 StorageClass, StorageClassAsWritten); 5370 5371 if (D.isInvalidType()) 5372 New->setInvalidDecl(); 5373 5374 // Add the parameter declaration into this scope. 5375 S->AddDecl(New); 5376 if (II) 5377 IdResolver.AddDecl(New); 5378 5379 ProcessDeclAttributes(S, New, D); 5380 5381 if (New->hasAttr<BlocksAttr>()) { 5382 Diag(New->getLocation(), diag::err_block_on_nonlocal); 5383 } 5384 return New; 5385} 5386 5387/// \brief Synthesizes a variable for a parameter arising from a 5388/// typedef. 5389ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 5390 SourceLocation Loc, 5391 QualType T) { 5392 /* FIXME: setting StartLoc == Loc. 5393 Would it be worth to modify callers so as to provide proper source 5394 location for the unnamed parameters, embedding the parameter's type? */ 5395 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, 5396 T, Context.getTrivialTypeSourceInfo(T, Loc), 5397 SC_None, SC_None, 0); 5398 Param->setImplicit(); 5399 return Param; 5400} 5401 5402void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 5403 ParmVarDecl * const *ParamEnd) { 5404 // Don't diagnose unused-parameter errors in template instantiations; we 5405 // will already have done so in the template itself. 5406 if (!ActiveTemplateInstantiations.empty()) 5407 return; 5408 5409 for (; Param != ParamEnd; ++Param) { 5410 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 5411 !(*Param)->hasAttr<UnusedAttr>()) { 5412 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 5413 << (*Param)->getDeclName(); 5414 } 5415 } 5416} 5417 5418void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 5419 ParmVarDecl * const *ParamEnd, 5420 QualType ReturnTy, 5421 NamedDecl *D) { 5422 if (LangOpts.NumLargeByValueCopy == 0) // No check. 5423 return; 5424 5425 // Warn if the return value is pass-by-value and larger than the specified 5426 // threshold. 5427 if (ReturnTy->isPODType()) { 5428 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 5429 if (Size > LangOpts.NumLargeByValueCopy) 5430 Diag(D->getLocation(), diag::warn_return_value_size) 5431 << D->getDeclName() << Size; 5432 } 5433 5434 // Warn if any parameter is pass-by-value and larger than the specified 5435 // threshold. 5436 for (; Param != ParamEnd; ++Param) { 5437 QualType T = (*Param)->getType(); 5438 if (!T->isPODType()) 5439 continue; 5440 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 5441 if (Size > LangOpts.NumLargeByValueCopy) 5442 Diag((*Param)->getLocation(), diag::warn_parameter_size) 5443 << (*Param)->getDeclName() << Size; 5444 } 5445} 5446 5447ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, 5448 SourceLocation NameLoc, IdentifierInfo *Name, 5449 QualType T, TypeSourceInfo *TSInfo, 5450 VarDecl::StorageClass StorageClass, 5451 VarDecl::StorageClass StorageClassAsWritten) { 5452 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, 5453 adjustParameterType(T), TSInfo, 5454 StorageClass, StorageClassAsWritten, 5455 0); 5456 5457 // Parameters can not be abstract class types. 5458 // For record types, this is done by the AbstractClassUsageDiagnoser once 5459 // the class has been completely parsed. 5460 if (!CurContext->isRecord() && 5461 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 5462 AbstractParamType)) 5463 New->setInvalidDecl(); 5464 5465 // Parameter declarators cannot be interface types. All ObjC objects are 5466 // passed by reference. 5467 if (T->isObjCObjectType()) { 5468 Diag(NameLoc, 5469 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 5470 New->setInvalidDecl(); 5471 } 5472 5473 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 5474 // duration shall not be qualified by an address-space qualifier." 5475 // Since all parameters have automatic store duration, they can not have 5476 // an address space. 5477 if (T.getAddressSpace() != 0) { 5478 Diag(NameLoc, diag::err_arg_with_address_space); 5479 New->setInvalidDecl(); 5480 } 5481 5482 return New; 5483} 5484 5485void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 5486 SourceLocation LocAfterDecls) { 5487 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 5488 5489 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 5490 // for a K&R function. 5491 if (!FTI.hasPrototype) { 5492 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 5493 --i; 5494 if (FTI.ArgInfo[i].Param == 0) { 5495 llvm::SmallString<256> Code; 5496 llvm::raw_svector_ostream(Code) << " int " 5497 << FTI.ArgInfo[i].Ident->getName() 5498 << ";\n"; 5499 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 5500 << FTI.ArgInfo[i].Ident 5501 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 5502 5503 // Implicitly declare the argument as type 'int' for lack of a better 5504 // type. 5505 AttributeFactory attrs; 5506 DeclSpec DS(attrs); 5507 const char* PrevSpec; // unused 5508 unsigned DiagID; // unused 5509 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 5510 PrevSpec, DiagID); 5511 Declarator ParamD(DS, Declarator::KNRTypeListContext); 5512 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 5513 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 5514 } 5515 } 5516 } 5517} 5518 5519Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 5520 Declarator &D) { 5521 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 5522 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 5523 Scope *ParentScope = FnBodyScope->getParent(); 5524 5525 Decl *DP = HandleDeclarator(ParentScope, D, 5526 MultiTemplateParamsArg(*this), 5527 /*IsFunctionDefinition=*/true); 5528 return ActOnStartOfFunctionDef(FnBodyScope, DP); 5529} 5530 5531static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 5532 // Don't warn about invalid declarations. 5533 if (FD->isInvalidDecl()) 5534 return false; 5535 5536 // Or declarations that aren't global. 5537 if (!FD->isGlobal()) 5538 return false; 5539 5540 // Don't warn about C++ member functions. 5541 if (isa<CXXMethodDecl>(FD)) 5542 return false; 5543 5544 // Don't warn about 'main'. 5545 if (FD->isMain()) 5546 return false; 5547 5548 // Don't warn about inline functions. 5549 if (FD->isInlined()) 5550 return false; 5551 5552 // Don't warn about function templates. 5553 if (FD->getDescribedFunctionTemplate()) 5554 return false; 5555 5556 // Don't warn about function template specializations. 5557 if (FD->isFunctionTemplateSpecialization()) 5558 return false; 5559 5560 bool MissingPrototype = true; 5561 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 5562 Prev; Prev = Prev->getPreviousDeclaration()) { 5563 // Ignore any declarations that occur in function or method 5564 // scope, because they aren't visible from the header. 5565 if (Prev->getDeclContext()->isFunctionOrMethod()) 5566 continue; 5567 5568 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 5569 break; 5570 } 5571 5572 return MissingPrototype; 5573} 5574 5575Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 5576 // Clear the last template instantiation error context. 5577 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 5578 5579 if (!D) 5580 return D; 5581 FunctionDecl *FD = 0; 5582 5583 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 5584 FD = FunTmpl->getTemplatedDecl(); 5585 else 5586 FD = cast<FunctionDecl>(D); 5587 5588 // Enter a new function scope 5589 PushFunctionScope(); 5590 5591 // See if this is a redefinition. 5592 // But don't complain if we're in GNU89 mode and the previous definition 5593 // was an extern inline function. 5594 const FunctionDecl *Definition; 5595 if (FD->hasBody(Definition) && 5596 !canRedefineFunction(Definition, getLangOptions())) { 5597 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 5598 Definition->getStorageClass() == SC_Extern) 5599 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 5600 << FD->getDeclName() << getLangOptions().CPlusPlus; 5601 else 5602 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 5603 Diag(Definition->getLocation(), diag::note_previous_definition); 5604 } 5605 5606 // Builtin functions cannot be defined. 5607 if (unsigned BuiltinID = FD->getBuiltinID()) { 5608 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 5609 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 5610 FD->setInvalidDecl(); 5611 } 5612 } 5613 5614 // The return type of a function definition must be complete 5615 // (C99 6.9.1p3, C++ [dcl.fct]p6). 5616 QualType ResultType = FD->getResultType(); 5617 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 5618 !FD->isInvalidDecl() && 5619 RequireCompleteType(FD->getLocation(), ResultType, 5620 diag::err_func_def_incomplete_result)) 5621 FD->setInvalidDecl(); 5622 5623 // GNU warning -Wmissing-prototypes: 5624 // Warn if a global function is defined without a previous 5625 // prototype declaration. This warning is issued even if the 5626 // definition itself provides a prototype. The aim is to detect 5627 // global functions that fail to be declared in header files. 5628 if (ShouldWarnAboutMissingPrototype(FD)) 5629 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 5630 5631 if (FnBodyScope) 5632 PushDeclContext(FnBodyScope, FD); 5633 5634 // Check the validity of our function parameters 5635 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 5636 /*CheckParameterNames=*/true); 5637 5638 // Introduce our parameters into the function scope 5639 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 5640 ParmVarDecl *Param = FD->getParamDecl(p); 5641 Param->setOwningFunction(FD); 5642 5643 // If this has an identifier, add it to the scope stack. 5644 if (Param->getIdentifier() && FnBodyScope) { 5645 CheckShadow(FnBodyScope, Param); 5646 5647 PushOnScopeChains(Param, FnBodyScope); 5648 } 5649 } 5650 5651 // Checking attributes of current function definition 5652 // dllimport attribute. 5653 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5654 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5655 // dllimport attribute cannot be directly applied to definition. 5656 if (!DA->isInherited()) { 5657 Diag(FD->getLocation(), 5658 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5659 << "dllimport"; 5660 FD->setInvalidDecl(); 5661 return FD; 5662 } 5663 5664 // Visual C++ appears to not think this is an issue, so only issue 5665 // a warning when Microsoft extensions are disabled. 5666 if (!LangOpts.Microsoft) { 5667 // If a symbol previously declared dllimport is later defined, the 5668 // attribute is ignored in subsequent references, and a warning is 5669 // emitted. 5670 Diag(FD->getLocation(), 5671 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5672 << FD->getName() << "dllimport"; 5673 } 5674 } 5675 return FD; 5676} 5677 5678/// \brief Given the set of return statements within a function body, 5679/// compute the variables that are subject to the named return value 5680/// optimization. 5681/// 5682/// Each of the variables that is subject to the named return value 5683/// optimization will be marked as NRVO variables in the AST, and any 5684/// return statement that has a marked NRVO variable as its NRVO candidate can 5685/// use the named return value optimization. 5686/// 5687/// This function applies a very simplistic algorithm for NRVO: if every return 5688/// statement in the function has the same NRVO candidate, that candidate is 5689/// the NRVO variable. 5690/// 5691/// FIXME: Employ a smarter algorithm that accounts for multiple return 5692/// statements and the lifetimes of the NRVO candidates. We should be able to 5693/// find a maximal set of NRVO variables. 5694static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5695 ReturnStmt **Returns = Scope->Returns.data(); 5696 5697 const VarDecl *NRVOCandidate = 0; 5698 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5699 if (!Returns[I]->getNRVOCandidate()) 5700 return; 5701 5702 if (!NRVOCandidate) 5703 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5704 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5705 return; 5706 } 5707 5708 if (NRVOCandidate) 5709 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5710} 5711 5712Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5713 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5714} 5715 5716Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5717 bool IsInstantiation) { 5718 FunctionDecl *FD = 0; 5719 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5720 if (FunTmpl) 5721 FD = FunTmpl->getTemplatedDecl(); 5722 else 5723 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5724 5725 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5726 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 5727 5728 if (FD) { 5729 FD->setBody(Body); 5730 if (FD->isMain()) { 5731 // C and C++ allow for main to automagically return 0. 5732 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5733 FD->setHasImplicitReturnZero(true); 5734 WP.disableCheckFallThrough(); 5735 } 5736 5737 if (!FD->isInvalidDecl()) { 5738 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5739 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 5740 FD->getResultType(), FD); 5741 5742 // If this is a constructor, we need a vtable. 5743 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5744 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5745 5746 ComputeNRVO(Body, getCurFunction()); 5747 } 5748 5749 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5750 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5751 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5752 MD->setBody(Body); 5753 if (Body) 5754 MD->setEndLoc(Body->getLocEnd()); 5755 if (!MD->isInvalidDecl()) { 5756 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5757 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 5758 MD->getResultType(), MD); 5759 } 5760 } else { 5761 return 0; 5762 } 5763 5764 // Verify and clean out per-function state. 5765 if (Body) { 5766 // C++ constructors that have function-try-blocks can't have return 5767 // statements in the handlers of that block. (C++ [except.handle]p14) 5768 // Verify this. 5769 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5770 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5771 5772 // Verify that that gotos and switch cases don't jump into scopes illegally. 5773 // Verify that that gotos and switch cases don't jump into scopes illegally. 5774 if (getCurFunction()->NeedsScopeChecking() && 5775 !dcl->isInvalidDecl() && 5776 !hasAnyErrorsInThisFunction()) 5777 DiagnoseInvalidJumps(Body); 5778 5779 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5780 if (!Destructor->getParent()->isDependentType()) 5781 CheckDestructor(Destructor); 5782 5783 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5784 Destructor->getParent()); 5785 } 5786 5787 // If any errors have occurred, clear out any temporaries that may have 5788 // been leftover. This ensures that these temporaries won't be picked up for 5789 // deletion in some later function. 5790 if (PP.getDiagnostics().hasErrorOccurred() || 5791 PP.getDiagnostics().getSuppressAllDiagnostics()) 5792 ExprTemporaries.clear(); 5793 else if (!isa<FunctionTemplateDecl>(dcl)) { 5794 // Since the body is valid, issue any analysis-based warnings that are 5795 // enabled. 5796 ActivePolicy = &WP; 5797 } 5798 5799 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5800 } 5801 5802 if (!IsInstantiation) 5803 PopDeclContext(); 5804 5805 PopFunctionOrBlockScope(ActivePolicy, dcl); 5806 5807 // If any errors have occurred, clear out any temporaries that may have 5808 // been leftover. This ensures that these temporaries won't be picked up for 5809 // deletion in some later function. 5810 if (getDiagnostics().hasErrorOccurred()) 5811 ExprTemporaries.clear(); 5812 5813 return dcl; 5814} 5815 5816/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5817/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5818NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5819 IdentifierInfo &II, Scope *S) { 5820 // Before we produce a declaration for an implicitly defined 5821 // function, see whether there was a locally-scoped declaration of 5822 // this name as a function or variable. If so, use that 5823 // (non-visible) declaration, and complain about it. 5824 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5825 = LocallyScopedExternalDecls.find(&II); 5826 if (Pos != LocallyScopedExternalDecls.end()) { 5827 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5828 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5829 return Pos->second; 5830 } 5831 5832 // Extension in C99. Legal in C90, but warn about it. 5833 if (II.getName().startswith("__builtin_")) 5834 Diag(Loc, diag::warn_builtin_unknown) << &II; 5835 else if (getLangOptions().C99) 5836 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5837 else 5838 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5839 5840 // Set a Declarator for the implicit definition: int foo(); 5841 const char *Dummy; 5842 AttributeFactory attrFactory; 5843 DeclSpec DS(attrFactory); 5844 unsigned DiagID; 5845 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5846 (void)Error; // Silence warning. 5847 assert(!Error && "Error setting up implicit decl!"); 5848 Declarator D(DS, Declarator::BlockContext); 5849 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5850 0, 0, true, SourceLocation(), 5851 EST_None, SourceLocation(), 5852 0, 0, 0, 0, Loc, Loc, D), 5853 DS.getAttributes(), 5854 SourceLocation()); 5855 D.SetIdentifier(&II, Loc); 5856 5857 // Insert this function into translation-unit scope. 5858 5859 DeclContext *PrevDC = CurContext; 5860 CurContext = Context.getTranslationUnitDecl(); 5861 5862 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5863 FD->setImplicit(); 5864 5865 CurContext = PrevDC; 5866 5867 AddKnownFunctionAttributes(FD); 5868 5869 return FD; 5870} 5871 5872/// \brief Adds any function attributes that we know a priori based on 5873/// the declaration of this function. 5874/// 5875/// These attributes can apply both to implicitly-declared builtins 5876/// (like __builtin___printf_chk) or to library-declared functions 5877/// like NSLog or printf. 5878void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5879 if (FD->isInvalidDecl()) 5880 return; 5881 5882 // If this is a built-in function, map its builtin attributes to 5883 // actual attributes. 5884 if (unsigned BuiltinID = FD->getBuiltinID()) { 5885 // Handle printf-formatting attributes. 5886 unsigned FormatIdx; 5887 bool HasVAListArg; 5888 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5889 if (!FD->getAttr<FormatAttr>()) 5890 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5891 "printf", FormatIdx+1, 5892 HasVAListArg ? 0 : FormatIdx+2)); 5893 } 5894 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5895 HasVAListArg)) { 5896 if (!FD->getAttr<FormatAttr>()) 5897 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5898 "scanf", FormatIdx+1, 5899 HasVAListArg ? 0 : FormatIdx+2)); 5900 } 5901 5902 // Mark const if we don't care about errno and that is the only 5903 // thing preventing the function from being const. This allows 5904 // IRgen to use LLVM intrinsics for such functions. 5905 if (!getLangOptions().MathErrno && 5906 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5907 if (!FD->getAttr<ConstAttr>()) 5908 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5909 } 5910 5911 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5912 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5913 if (Context.BuiltinInfo.isConst(BuiltinID)) 5914 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5915 } 5916 5917 IdentifierInfo *Name = FD->getIdentifier(); 5918 if (!Name) 5919 return; 5920 if ((!getLangOptions().CPlusPlus && 5921 FD->getDeclContext()->isTranslationUnit()) || 5922 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5923 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5924 LinkageSpecDecl::lang_c)) { 5925 // Okay: this could be a libc/libm/Objective-C function we know 5926 // about. 5927 } else 5928 return; 5929 5930 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5931 // FIXME: NSLog and NSLogv should be target specific 5932 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5933 // FIXME: We known better than our headers. 5934 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5935 } else 5936 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5937 "printf", 1, 5938 Name->isStr("NSLogv") ? 0 : 2)); 5939 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5940 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5941 // target-specific builtins, perhaps? 5942 if (!FD->getAttr<FormatAttr>()) 5943 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5944 "printf", 2, 5945 Name->isStr("vasprintf") ? 0 : 3)); 5946 } 5947} 5948 5949TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5950 TypeSourceInfo *TInfo) { 5951 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5952 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5953 5954 if (!TInfo) { 5955 assert(D.isInvalidType() && "no declarator info for valid type"); 5956 TInfo = Context.getTrivialTypeSourceInfo(T); 5957 } 5958 5959 // Scope manipulation handled by caller. 5960 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5961 D.getSourceRange().getBegin(), 5962 D.getIdentifierLoc(), 5963 D.getIdentifier(), 5964 TInfo); 5965 5966 // Bail out immediately if we have an invalid declaration. 5967 if (D.isInvalidType()) { 5968 NewTD->setInvalidDecl(); 5969 return NewTD; 5970 } 5971 5972 // C++ [dcl.typedef]p8: 5973 // If the typedef declaration defines an unnamed class (or 5974 // enum), the first typedef-name declared by the declaration 5975 // to be that class type (or enum type) is used to denote the 5976 // class type (or enum type) for linkage purposes only. 5977 // We need to check whether the type was declared in the declaration. 5978 switch (D.getDeclSpec().getTypeSpecType()) { 5979 case TST_enum: 5980 case TST_struct: 5981 case TST_union: 5982 case TST_class: { 5983 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 5984 5985 // Do nothing if the tag is not anonymous or already has an 5986 // associated typedef (from an earlier typedef in this decl group). 5987 if (tagFromDeclSpec->getIdentifier()) break; 5988 if (tagFromDeclSpec->getTypedefForAnonDecl()) break; 5989 5990 // A well-formed anonymous tag must always be a TUK_Definition. 5991 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 5992 5993 // The type must match the tag exactly; no qualifiers allowed. 5994 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 5995 break; 5996 5997 // Otherwise, set this is the anon-decl typedef for the tag. 5998 tagFromDeclSpec->setTypedefForAnonDecl(NewTD); 5999 break; 6000 } 6001 6002 default: 6003 break; 6004 } 6005 6006 return NewTD; 6007} 6008 6009 6010/// \brief Determine whether a tag with a given kind is acceptable 6011/// as a redeclaration of the given tag declaration. 6012/// 6013/// \returns true if the new tag kind is acceptable, false otherwise. 6014bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 6015 TagTypeKind NewTag, 6016 SourceLocation NewTagLoc, 6017 const IdentifierInfo &Name) { 6018 // C++ [dcl.type.elab]p3: 6019 // The class-key or enum keyword present in the 6020 // elaborated-type-specifier shall agree in kind with the 6021 // declaration to which the name in the elaborated-type-specifier 6022 // refers. This rule also applies to the form of 6023 // elaborated-type-specifier that declares a class-name or 6024 // friend class since it can be construed as referring to the 6025 // definition of the class. Thus, in any 6026 // elaborated-type-specifier, the enum keyword shall be used to 6027 // refer to an enumeration (7.2), the union class-key shall be 6028 // used to refer to a union (clause 9), and either the class or 6029 // struct class-key shall be used to refer to a class (clause 9) 6030 // declared using the class or struct class-key. 6031 TagTypeKind OldTag = Previous->getTagKind(); 6032 if (OldTag == NewTag) 6033 return true; 6034 6035 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 6036 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 6037 // Warn about the struct/class tag mismatch. 6038 bool isTemplate = false; 6039 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 6040 isTemplate = Record->getDescribedClassTemplate(); 6041 6042 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6043 << (NewTag == TTK_Class) 6044 << isTemplate << &Name 6045 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 6046 OldTag == TTK_Class? "class" : "struct"); 6047 Diag(Previous->getLocation(), diag::note_previous_use); 6048 return true; 6049 } 6050 return false; 6051} 6052 6053/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 6054/// former case, Name will be non-null. In the later case, Name will be null. 6055/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 6056/// reference/declaration/definition of a tag. 6057Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 6058 SourceLocation KWLoc, CXXScopeSpec &SS, 6059 IdentifierInfo *Name, SourceLocation NameLoc, 6060 AttributeList *Attr, AccessSpecifier AS, 6061 MultiTemplateParamsArg TemplateParameterLists, 6062 bool &OwnedDecl, bool &IsDependent, 6063 bool ScopedEnum, bool ScopedEnumUsesClassTag, 6064 TypeResult UnderlyingType) { 6065 // If this is not a definition, it must have a name. 6066 assert((Name != 0 || TUK == TUK_Definition) && 6067 "Nameless record must be a definition!"); 6068 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 6069 6070 OwnedDecl = false; 6071 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 6072 6073 // FIXME: Check explicit specializations more carefully. 6074 bool isExplicitSpecialization = false; 6075 bool Invalid = false; 6076 6077 // We only need to do this matching if we have template parameters 6078 // or a scope specifier, which also conveniently avoids this work 6079 // for non-C++ cases. 6080 if (TemplateParameterLists.size() > 0 || 6081 (SS.isNotEmpty() && TUK != TUK_Reference)) { 6082 if (TemplateParameterList *TemplateParams 6083 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 6084 TemplateParameterLists.get(), 6085 TemplateParameterLists.size(), 6086 TUK == TUK_Friend, 6087 isExplicitSpecialization, 6088 Invalid)) { 6089 if (TemplateParams->size() > 0) { 6090 // This is a declaration or definition of a class template (which may 6091 // be a member of another template). 6092 6093 if (Invalid) 6094 return 0; 6095 6096 OwnedDecl = false; 6097 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6098 SS, Name, NameLoc, Attr, 6099 TemplateParams, AS, 6100 TemplateParameterLists.size() - 1, 6101 (TemplateParameterList**) TemplateParameterLists.release()); 6102 return Result.get(); 6103 } else { 6104 // The "template<>" header is extraneous. 6105 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6106 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6107 isExplicitSpecialization = true; 6108 } 6109 } 6110 } 6111 6112 // Figure out the underlying type if this a enum declaration. We need to do 6113 // this early, because it's needed to detect if this is an incompatible 6114 // redeclaration. 6115 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6116 6117 if (Kind == TTK_Enum) { 6118 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6119 // No underlying type explicitly specified, or we failed to parse the 6120 // type, default to int. 6121 EnumUnderlying = Context.IntTy.getTypePtr(); 6122 else if (UnderlyingType.get()) { 6123 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6124 // integral type; any cv-qualification is ignored. 6125 TypeSourceInfo *TI = 0; 6126 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6127 EnumUnderlying = TI; 6128 6129 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6130 6131 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6132 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6133 << T; 6134 // Recover by falling back to int. 6135 EnumUnderlying = Context.IntTy.getTypePtr(); 6136 } 6137 6138 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6139 UPPC_FixedUnderlyingType)) 6140 EnumUnderlying = Context.IntTy.getTypePtr(); 6141 6142 } else if (getLangOptions().Microsoft) 6143 // Microsoft enums are always of int type. 6144 EnumUnderlying = Context.IntTy.getTypePtr(); 6145 } 6146 6147 DeclContext *SearchDC = CurContext; 6148 DeclContext *DC = CurContext; 6149 bool isStdBadAlloc = false; 6150 6151 RedeclarationKind Redecl = ForRedeclaration; 6152 if (TUK == TUK_Friend || TUK == TUK_Reference) 6153 Redecl = NotForRedeclaration; 6154 6155 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6156 6157 if (Name && SS.isNotEmpty()) { 6158 // We have a nested-name tag ('struct foo::bar'). 6159 6160 // Check for invalid 'foo::'. 6161 if (SS.isInvalid()) { 6162 Name = 0; 6163 goto CreateNewDecl; 6164 } 6165 6166 // If this is a friend or a reference to a class in a dependent 6167 // context, don't try to make a decl for it. 6168 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6169 DC = computeDeclContext(SS, false); 6170 if (!DC) { 6171 IsDependent = true; 6172 return 0; 6173 } 6174 } else { 6175 DC = computeDeclContext(SS, true); 6176 if (!DC) { 6177 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6178 << SS.getRange(); 6179 return 0; 6180 } 6181 } 6182 6183 if (RequireCompleteDeclContext(SS, DC)) 6184 return 0; 6185 6186 SearchDC = DC; 6187 // Look-up name inside 'foo::'. 6188 LookupQualifiedName(Previous, DC); 6189 6190 if (Previous.isAmbiguous()) 6191 return 0; 6192 6193 if (Previous.empty()) { 6194 // Name lookup did not find anything. However, if the 6195 // nested-name-specifier refers to the current instantiation, 6196 // and that current instantiation has any dependent base 6197 // classes, we might find something at instantiation time: treat 6198 // this as a dependent elaborated-type-specifier. 6199 // But this only makes any sense for reference-like lookups. 6200 if (Previous.wasNotFoundInCurrentInstantiation() && 6201 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6202 IsDependent = true; 6203 return 0; 6204 } 6205 6206 // A tag 'foo::bar' must already exist. 6207 Diag(NameLoc, diag::err_not_tag_in_scope) 6208 << Kind << Name << DC << SS.getRange(); 6209 Name = 0; 6210 Invalid = true; 6211 goto CreateNewDecl; 6212 } 6213 } else if (Name) { 6214 // If this is a named struct, check to see if there was a previous forward 6215 // declaration or definition. 6216 // FIXME: We're looking into outer scopes here, even when we 6217 // shouldn't be. Doing so can result in ambiguities that we 6218 // shouldn't be diagnosing. 6219 LookupName(Previous, S); 6220 6221 // Note: there used to be some attempt at recovery here. 6222 if (Previous.isAmbiguous()) 6223 return 0; 6224 6225 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6226 // FIXME: This makes sure that we ignore the contexts associated 6227 // with C structs, unions, and enums when looking for a matching 6228 // tag declaration or definition. See the similar lookup tweak 6229 // in Sema::LookupName; is there a better way to deal with this? 6230 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 6231 SearchDC = SearchDC->getParent(); 6232 } 6233 } else if (S->isFunctionPrototypeScope()) { 6234 // If this is an enum declaration in function prototype scope, set its 6235 // initial context to the translation unit. 6236 SearchDC = Context.getTranslationUnitDecl(); 6237 } 6238 6239 if (Previous.isSingleResult() && 6240 Previous.getFoundDecl()->isTemplateParameter()) { 6241 // Maybe we will complain about the shadowed template parameter. 6242 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 6243 // Just pretend that we didn't see the previous declaration. 6244 Previous.clear(); 6245 } 6246 6247 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 6248 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 6249 // This is a declaration of or a reference to "std::bad_alloc". 6250 isStdBadAlloc = true; 6251 6252 if (Previous.empty() && StdBadAlloc) { 6253 // std::bad_alloc has been implicitly declared (but made invisible to 6254 // name lookup). Fill in this implicit declaration as the previous 6255 // declaration, so that the declarations get chained appropriately. 6256 Previous.addDecl(getStdBadAlloc()); 6257 } 6258 } 6259 6260 // If we didn't find a previous declaration, and this is a reference 6261 // (or friend reference), move to the correct scope. In C++, we 6262 // also need to do a redeclaration lookup there, just in case 6263 // there's a shadow friend decl. 6264 if (Name && Previous.empty() && 6265 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6266 if (Invalid) goto CreateNewDecl; 6267 assert(SS.isEmpty()); 6268 6269 if (TUK == TUK_Reference) { 6270 // C++ [basic.scope.pdecl]p5: 6271 // -- for an elaborated-type-specifier of the form 6272 // 6273 // class-key identifier 6274 // 6275 // if the elaborated-type-specifier is used in the 6276 // decl-specifier-seq or parameter-declaration-clause of a 6277 // function defined in namespace scope, the identifier is 6278 // declared as a class-name in the namespace that contains 6279 // the declaration; otherwise, except as a friend 6280 // declaration, the identifier is declared in the smallest 6281 // non-class, non-function-prototype scope that contains the 6282 // declaration. 6283 // 6284 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 6285 // C structs and unions. 6286 // 6287 // It is an error in C++ to declare (rather than define) an enum 6288 // type, including via an elaborated type specifier. We'll 6289 // diagnose that later; for now, declare the enum in the same 6290 // scope as we would have picked for any other tag type. 6291 // 6292 // GNU C also supports this behavior as part of its incomplete 6293 // enum types extension, while GNU C++ does not. 6294 // 6295 // Find the context where we'll be declaring the tag. 6296 // FIXME: We would like to maintain the current DeclContext as the 6297 // lexical context, 6298 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 6299 SearchDC = SearchDC->getParent(); 6300 6301 // Find the scope where we'll be declaring the tag. 6302 while (S->isClassScope() || 6303 (getLangOptions().CPlusPlus && 6304 S->isFunctionPrototypeScope()) || 6305 ((S->getFlags() & Scope::DeclScope) == 0) || 6306 (S->getEntity() && 6307 ((DeclContext *)S->getEntity())->isTransparentContext())) 6308 S = S->getParent(); 6309 } else { 6310 assert(TUK == TUK_Friend); 6311 // C++ [namespace.memdef]p3: 6312 // If a friend declaration in a non-local class first declares a 6313 // class or function, the friend class or function is a member of 6314 // the innermost enclosing namespace. 6315 SearchDC = SearchDC->getEnclosingNamespaceContext(); 6316 } 6317 6318 // In C++, we need to do a redeclaration lookup to properly 6319 // diagnose some problems. 6320 if (getLangOptions().CPlusPlus) { 6321 Previous.setRedeclarationKind(ForRedeclaration); 6322 LookupQualifiedName(Previous, SearchDC); 6323 } 6324 } 6325 6326 if (!Previous.empty()) { 6327 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 6328 6329 // It's okay to have a tag decl in the same scope as a typedef 6330 // which hides a tag decl in the same scope. Finding this 6331 // insanity with a redeclaration lookup can only actually happen 6332 // in C++. 6333 // 6334 // This is also okay for elaborated-type-specifiers, which is 6335 // technically forbidden by the current standard but which is 6336 // okay according to the likely resolution of an open issue; 6337 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 6338 if (getLangOptions().CPlusPlus) { 6339 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 6340 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 6341 TagDecl *Tag = TT->getDecl(); 6342 if (Tag->getDeclName() == Name && 6343 Tag->getDeclContext()->getRedeclContext() 6344 ->Equals(TD->getDeclContext()->getRedeclContext())) { 6345 PrevDecl = Tag; 6346 Previous.clear(); 6347 Previous.addDecl(Tag); 6348 Previous.resolveKind(); 6349 } 6350 } 6351 } 6352 } 6353 6354 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 6355 // If this is a use of a previous tag, or if the tag is already declared 6356 // in the same scope (so that the definition/declaration completes or 6357 // rementions the tag), reuse the decl. 6358 if (TUK == TUK_Reference || TUK == TUK_Friend || 6359 isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { 6360 // Make sure that this wasn't declared as an enum and now used as a 6361 // struct or something similar. 6362 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 6363 bool SafeToContinue 6364 = (PrevTagDecl->getTagKind() != TTK_Enum && 6365 Kind != TTK_Enum); 6366 if (SafeToContinue) 6367 Diag(KWLoc, diag::err_use_with_wrong_tag) 6368 << Name 6369 << FixItHint::CreateReplacement(SourceRange(KWLoc), 6370 PrevTagDecl->getKindName()); 6371 else 6372 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 6373 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6374 6375 if (SafeToContinue) 6376 Kind = PrevTagDecl->getTagKind(); 6377 else { 6378 // Recover by making this an anonymous redefinition. 6379 Name = 0; 6380 Previous.clear(); 6381 Invalid = true; 6382 } 6383 } 6384 6385 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 6386 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 6387 6388 // All conflicts with previous declarations are recovered by 6389 // returning the previous declaration. 6390 if (ScopedEnum != PrevEnum->isScoped()) { 6391 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 6392 << PrevEnum->isScoped(); 6393 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6394 return PrevTagDecl; 6395 } 6396 else if (EnumUnderlying && PrevEnum->isFixed()) { 6397 QualType T; 6398 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6399 T = TI->getType(); 6400 else 6401 T = QualType(EnumUnderlying.get<const Type*>(), 0); 6402 6403 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 6404 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 6405 diag::err_enum_redeclare_type_mismatch) 6406 << T 6407 << PrevEnum->getIntegerType(); 6408 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6409 return PrevTagDecl; 6410 } 6411 } 6412 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 6413 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 6414 << PrevEnum->isFixed(); 6415 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6416 return PrevTagDecl; 6417 } 6418 } 6419 6420 if (!Invalid) { 6421 // If this is a use, just return the declaration we found. 6422 6423 // FIXME: In the future, return a variant or some other clue 6424 // for the consumer of this Decl to know it doesn't own it. 6425 // For our current ASTs this shouldn't be a problem, but will 6426 // need to be changed with DeclGroups. 6427 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 6428 TUK == TUK_Friend) 6429 return PrevTagDecl; 6430 6431 // Diagnose attempts to redefine a tag. 6432 if (TUK == TUK_Definition) { 6433 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 6434 // If we're defining a specialization and the previous definition 6435 // is from an implicit instantiation, don't emit an error 6436 // here; we'll catch this in the general case below. 6437 if (!isExplicitSpecialization || 6438 !isa<CXXRecordDecl>(Def) || 6439 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 6440 == TSK_ExplicitSpecialization) { 6441 Diag(NameLoc, diag::err_redefinition) << Name; 6442 Diag(Def->getLocation(), diag::note_previous_definition); 6443 // If this is a redefinition, recover by making this 6444 // struct be anonymous, which will make any later 6445 // references get the previous definition. 6446 Name = 0; 6447 Previous.clear(); 6448 Invalid = true; 6449 } 6450 } else { 6451 // If the type is currently being defined, complain 6452 // about a nested redefinition. 6453 const TagType *Tag 6454 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 6455 if (Tag->isBeingDefined()) { 6456 Diag(NameLoc, diag::err_nested_redefinition) << Name; 6457 Diag(PrevTagDecl->getLocation(), 6458 diag::note_previous_definition); 6459 Name = 0; 6460 Previous.clear(); 6461 Invalid = true; 6462 } 6463 } 6464 6465 // Okay, this is definition of a previously declared or referenced 6466 // tag PrevDecl. We're going to create a new Decl for it. 6467 } 6468 } 6469 // If we get here we have (another) forward declaration or we 6470 // have a definition. Just create a new decl. 6471 6472 } else { 6473 // If we get here, this is a definition of a new tag type in a nested 6474 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 6475 // new decl/type. We set PrevDecl to NULL so that the entities 6476 // have distinct types. 6477 Previous.clear(); 6478 } 6479 // If we get here, we're going to create a new Decl. If PrevDecl 6480 // is non-NULL, it's a definition of the tag declared by 6481 // PrevDecl. If it's NULL, we have a new definition. 6482 6483 6484 // Otherwise, PrevDecl is not a tag, but was found with tag 6485 // lookup. This is only actually possible in C++, where a few 6486 // things like templates still live in the tag namespace. 6487 } else { 6488 assert(getLangOptions().CPlusPlus); 6489 6490 // Use a better diagnostic if an elaborated-type-specifier 6491 // found the wrong kind of type on the first 6492 // (non-redeclaration) lookup. 6493 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 6494 !Previous.isForRedeclaration()) { 6495 unsigned Kind = 0; 6496 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6497 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6498 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 6499 Diag(PrevDecl->getLocation(), diag::note_declared_at); 6500 Invalid = true; 6501 6502 // Otherwise, only diagnose if the declaration is in scope. 6503 } else if (!isDeclInScope(PrevDecl, SearchDC, S, 6504 isExplicitSpecialization)) { 6505 // do nothing 6506 6507 // Diagnose implicit declarations introduced by elaborated types. 6508 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 6509 unsigned Kind = 0; 6510 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6511 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6512 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 6513 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6514 Invalid = true; 6515 6516 // Otherwise it's a declaration. Call out a particularly common 6517 // case here. 6518 } else if (isa<TypedefDecl>(PrevDecl)) { 6519 Diag(NameLoc, diag::err_tag_definition_of_typedef) 6520 << Name 6521 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 6522 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6523 Invalid = true; 6524 6525 // Otherwise, diagnose. 6526 } else { 6527 // The tag name clashes with something else in the target scope, 6528 // issue an error and recover by making this tag be anonymous. 6529 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 6530 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6531 Name = 0; 6532 Invalid = true; 6533 } 6534 6535 // The existing declaration isn't relevant to us; we're in a 6536 // new scope, so clear out the previous declaration. 6537 Previous.clear(); 6538 } 6539 } 6540 6541CreateNewDecl: 6542 6543 TagDecl *PrevDecl = 0; 6544 if (Previous.isSingleResult()) 6545 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 6546 6547 // If there is an identifier, use the location of the identifier as the 6548 // location of the decl, otherwise use the location of the struct/union 6549 // keyword. 6550 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 6551 6552 // Otherwise, create a new declaration. If there is a previous 6553 // declaration of the same entity, the two will be linked via 6554 // PrevDecl. 6555 TagDecl *New; 6556 6557 bool IsForwardReference = false; 6558 if (Kind == TTK_Enum) { 6559 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6560 // enum X { A, B, C } D; D should chain to X. 6561 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, 6562 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 6563 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 6564 // If this is an undefined enum, warn. 6565 if (TUK != TUK_Definition && !Invalid) { 6566 TagDecl *Def; 6567 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 6568 // C++0x: 7.2p2: opaque-enum-declaration. 6569 // Conflicts are diagnosed above. Do nothing. 6570 } 6571 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 6572 Diag(Loc, diag::ext_forward_ref_enum_def) 6573 << New; 6574 Diag(Def->getLocation(), diag::note_previous_definition); 6575 } else { 6576 unsigned DiagID = diag::ext_forward_ref_enum; 6577 if (getLangOptions().Microsoft) 6578 DiagID = diag::ext_ms_forward_ref_enum; 6579 else if (getLangOptions().CPlusPlus) 6580 DiagID = diag::err_forward_ref_enum; 6581 Diag(Loc, DiagID); 6582 6583 // If this is a forward-declared reference to an enumeration, make a 6584 // note of it; we won't actually be introducing the declaration into 6585 // the declaration context. 6586 if (TUK == TUK_Reference) 6587 IsForwardReference = true; 6588 } 6589 } 6590 6591 if (EnumUnderlying) { 6592 EnumDecl *ED = cast<EnumDecl>(New); 6593 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6594 ED->setIntegerTypeSourceInfo(TI); 6595 else 6596 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 6597 ED->setPromotionType(ED->getIntegerType()); 6598 } 6599 6600 } else { 6601 // struct/union/class 6602 6603 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6604 // struct X { int A; } D; D should chain to X. 6605 if (getLangOptions().CPlusPlus) { 6606 // FIXME: Look for a way to use RecordDecl for simple structs. 6607 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 6608 cast_or_null<CXXRecordDecl>(PrevDecl)); 6609 6610 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 6611 StdBadAlloc = cast<CXXRecordDecl>(New); 6612 } else 6613 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 6614 cast_or_null<RecordDecl>(PrevDecl)); 6615 } 6616 6617 // Maybe add qualifier info. 6618 if (SS.isNotEmpty()) { 6619 if (SS.isSet()) { 6620 New->setQualifierInfo(SS.getWithLocInContext(Context)); 6621 if (TemplateParameterLists.size() > 0) { 6622 New->setTemplateParameterListsInfo(Context, 6623 TemplateParameterLists.size(), 6624 (TemplateParameterList**) TemplateParameterLists.release()); 6625 } 6626 } 6627 else 6628 Invalid = true; 6629 } 6630 6631 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 6632 // Add alignment attributes if necessary; these attributes are checked when 6633 // the ASTContext lays out the structure. 6634 // 6635 // It is important for implementing the correct semantics that this 6636 // happen here (in act on tag decl). The #pragma pack stack is 6637 // maintained as a result of parser callbacks which can occur at 6638 // many points during the parsing of a struct declaration (because 6639 // the #pragma tokens are effectively skipped over during the 6640 // parsing of the struct). 6641 AddAlignmentAttributesForRecord(RD); 6642 } 6643 6644 // If this is a specialization of a member class (of a class template), 6645 // check the specialization. 6646 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 6647 Invalid = true; 6648 6649 if (Invalid) 6650 New->setInvalidDecl(); 6651 6652 if (Attr) 6653 ProcessDeclAttributeList(S, New, Attr); 6654 6655 // If we're declaring or defining a tag in function prototype scope 6656 // in C, note that this type can only be used within the function. 6657 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6658 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6659 6660 // Set the lexical context. If the tag has a C++ scope specifier, the 6661 // lexical context will be different from the semantic context. 6662 New->setLexicalDeclContext(CurContext); 6663 6664 // Mark this as a friend decl if applicable. 6665 if (TUK == TUK_Friend) 6666 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6667 6668 // Set the access specifier. 6669 if (!Invalid && SearchDC->isRecord()) 6670 SetMemberAccessSpecifier(New, PrevDecl, AS); 6671 6672 if (TUK == TUK_Definition) 6673 New->startDefinition(); 6674 6675 // If this has an identifier, add it to the scope stack. 6676 if (TUK == TUK_Friend) { 6677 // We might be replacing an existing declaration in the lookup tables; 6678 // if so, borrow its access specifier. 6679 if (PrevDecl) 6680 New->setAccess(PrevDecl->getAccess()); 6681 6682 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6683 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6684 if (Name) // can be null along some error paths 6685 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6686 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6687 } else if (Name) { 6688 S = getNonFieldDeclScope(S); 6689 PushOnScopeChains(New, S, !IsForwardReference); 6690 if (IsForwardReference) 6691 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6692 6693 } else { 6694 CurContext->addDecl(New); 6695 } 6696 6697 // If this is the C FILE type, notify the AST context. 6698 if (IdentifierInfo *II = New->getIdentifier()) 6699 if (!New->isInvalidDecl() && 6700 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6701 II->isStr("FILE")) 6702 Context.setFILEDecl(New); 6703 6704 OwnedDecl = true; 6705 return New; 6706} 6707 6708void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6709 AdjustDeclIfTemplate(TagD); 6710 TagDecl *Tag = cast<TagDecl>(TagD); 6711 6712 // Enter the tag context. 6713 PushDeclContext(S, Tag); 6714} 6715 6716void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6717 ClassVirtSpecifiers &CVS, 6718 SourceLocation LBraceLoc) { 6719 AdjustDeclIfTemplate(TagD); 6720 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6721 6722 FieldCollector->StartClass(); 6723 6724 if (!Record->getIdentifier()) 6725 return; 6726 6727 if (CVS.isFinalSpecified()) 6728 Record->addAttr(new (Context) FinalAttr(CVS.getFinalLoc(), Context)); 6729 if (CVS.isExplicitSpecified()) 6730 Record->addAttr(new (Context) ExplicitAttr(CVS.getExplicitLoc(), Context)); 6731 6732 // C++ [class]p2: 6733 // [...] The class-name is also inserted into the scope of the 6734 // class itself; this is known as the injected-class-name. For 6735 // purposes of access checking, the injected-class-name is treated 6736 // as if it were a public member name. 6737 CXXRecordDecl *InjectedClassName 6738 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, 6739 Record->getLocStart(), Record->getLocation(), 6740 Record->getIdentifier(), 6741 /*PrevDecl=*/0, 6742 /*DelayTypeCreation=*/true); 6743 Context.getTypeDeclType(InjectedClassName, Record); 6744 InjectedClassName->setImplicit(); 6745 InjectedClassName->setAccess(AS_public); 6746 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6747 InjectedClassName->setDescribedClassTemplate(Template); 6748 PushOnScopeChains(InjectedClassName, S); 6749 assert(InjectedClassName->isInjectedClassName() && 6750 "Broken injected-class-name"); 6751} 6752 6753void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6754 SourceLocation RBraceLoc) { 6755 AdjustDeclIfTemplate(TagD); 6756 TagDecl *Tag = cast<TagDecl>(TagD); 6757 Tag->setRBraceLoc(RBraceLoc); 6758 6759 if (isa<CXXRecordDecl>(Tag)) 6760 FieldCollector->FinishClass(); 6761 6762 // Exit this scope of this tag's definition. 6763 PopDeclContext(); 6764 6765 // Notify the consumer that we've defined a tag. 6766 Consumer.HandleTagDeclDefinition(Tag); 6767} 6768 6769void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6770 AdjustDeclIfTemplate(TagD); 6771 TagDecl *Tag = cast<TagDecl>(TagD); 6772 Tag->setInvalidDecl(); 6773 6774 // We're undoing ActOnTagStartDefinition here, not 6775 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6776 // the FieldCollector. 6777 6778 PopDeclContext(); 6779} 6780 6781// Note that FieldName may be null for anonymous bitfields. 6782bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6783 QualType FieldTy, const Expr *BitWidth, 6784 bool *ZeroWidth) { 6785 // Default to true; that shouldn't confuse checks for emptiness 6786 if (ZeroWidth) 6787 *ZeroWidth = true; 6788 6789 // C99 6.7.2.1p4 - verify the field type. 6790 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6791 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6792 // Handle incomplete types with specific error. 6793 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6794 return true; 6795 if (FieldName) 6796 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6797 << FieldName << FieldTy << BitWidth->getSourceRange(); 6798 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6799 << FieldTy << BitWidth->getSourceRange(); 6800 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 6801 UPPC_BitFieldWidth)) 6802 return true; 6803 6804 // If the bit-width is type- or value-dependent, don't try to check 6805 // it now. 6806 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6807 return false; 6808 6809 llvm::APSInt Value; 6810 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6811 return true; 6812 6813 if (Value != 0 && ZeroWidth) 6814 *ZeroWidth = false; 6815 6816 // Zero-width bitfield is ok for anonymous field. 6817 if (Value == 0 && FieldName) 6818 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6819 6820 if (Value.isSigned() && Value.isNegative()) { 6821 if (FieldName) 6822 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6823 << FieldName << Value.toString(10); 6824 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6825 << Value.toString(10); 6826 } 6827 6828 if (!FieldTy->isDependentType()) { 6829 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6830 if (Value.getZExtValue() > TypeSize) { 6831 if (!getLangOptions().CPlusPlus) { 6832 if (FieldName) 6833 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6834 << FieldName << (unsigned)Value.getZExtValue() 6835 << (unsigned)TypeSize; 6836 6837 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6838 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6839 } 6840 6841 if (FieldName) 6842 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6843 << FieldName << (unsigned)Value.getZExtValue() 6844 << (unsigned)TypeSize; 6845 else 6846 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6847 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6848 } 6849 } 6850 6851 return false; 6852} 6853 6854/// ActOnField - Each field of a struct/union/class is passed into this in order 6855/// to create a FieldDecl object for it. 6856Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6857 SourceLocation DeclStart, 6858 Declarator &D, ExprTy *BitfieldWidth) { 6859 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6860 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6861 AS_public); 6862 return Res; 6863} 6864 6865/// HandleField - Analyze a field of a C struct or a C++ data member. 6866/// 6867FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6868 SourceLocation DeclStart, 6869 Declarator &D, Expr *BitWidth, 6870 AccessSpecifier AS) { 6871 IdentifierInfo *II = D.getIdentifier(); 6872 SourceLocation Loc = DeclStart; 6873 if (II) Loc = D.getIdentifierLoc(); 6874 6875 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6876 QualType T = TInfo->getType(); 6877 if (getLangOptions().CPlusPlus) { 6878 CheckExtraCXXDefaultArguments(D); 6879 6880 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 6881 UPPC_DataMemberType)) { 6882 D.setInvalidType(); 6883 T = Context.IntTy; 6884 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 6885 } 6886 } 6887 6888 DiagnoseFunctionSpecifiers(D); 6889 6890 if (D.getDeclSpec().isThreadSpecified()) 6891 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6892 6893 // Check to see if this name was declared as a member previously 6894 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6895 LookupName(Previous, S); 6896 assert((Previous.empty() || Previous.isOverloadedResult() || 6897 Previous.isSingleResult()) 6898 && "Lookup of member name should be either overloaded, single or null"); 6899 6900 // If the name is overloaded then get any declaration else get the single result 6901 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6902 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6903 6904 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6905 // Maybe we will complain about the shadowed template parameter. 6906 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6907 // Just pretend that we didn't see the previous declaration. 6908 PrevDecl = 0; 6909 } 6910 6911 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6912 PrevDecl = 0; 6913 6914 bool Mutable 6915 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6916 SourceLocation TSSL = D.getSourceRange().getBegin(); 6917 FieldDecl *NewFD 6918 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6919 AS, PrevDecl, &D); 6920 6921 if (NewFD->isInvalidDecl()) 6922 Record->setInvalidDecl(); 6923 6924 if (NewFD->isInvalidDecl() && PrevDecl) { 6925 // Don't introduce NewFD into scope; there's already something 6926 // with the same name in the same scope. 6927 } else if (II) { 6928 PushOnScopeChains(NewFD, S); 6929 } else 6930 Record->addDecl(NewFD); 6931 6932 return NewFD; 6933} 6934 6935/// \brief Build a new FieldDecl and check its well-formedness. 6936/// 6937/// This routine builds a new FieldDecl given the fields name, type, 6938/// record, etc. \p PrevDecl should refer to any previous declaration 6939/// with the same name and in the same scope as the field to be 6940/// created. 6941/// 6942/// \returns a new FieldDecl. 6943/// 6944/// \todo The Declarator argument is a hack. It will be removed once 6945FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6946 TypeSourceInfo *TInfo, 6947 RecordDecl *Record, SourceLocation Loc, 6948 bool Mutable, Expr *BitWidth, 6949 SourceLocation TSSL, 6950 AccessSpecifier AS, NamedDecl *PrevDecl, 6951 Declarator *D) { 6952 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6953 bool InvalidDecl = false; 6954 if (D) InvalidDecl = D->isInvalidType(); 6955 6956 // If we receive a broken type, recover by assuming 'int' and 6957 // marking this declaration as invalid. 6958 if (T.isNull()) { 6959 InvalidDecl = true; 6960 T = Context.IntTy; 6961 } 6962 6963 QualType EltTy = Context.getBaseElementType(T); 6964 if (!EltTy->isDependentType() && 6965 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6966 // Fields of incomplete type force their record to be invalid. 6967 Record->setInvalidDecl(); 6968 InvalidDecl = true; 6969 } 6970 6971 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6972 // than a variably modified type. 6973 if (!InvalidDecl && T->isVariablyModifiedType()) { 6974 bool SizeIsNegative; 6975 llvm::APSInt Oversized; 6976 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6977 SizeIsNegative, 6978 Oversized); 6979 if (!FixedTy.isNull()) { 6980 Diag(Loc, diag::warn_illegal_constant_array_size); 6981 T = FixedTy; 6982 } else { 6983 if (SizeIsNegative) 6984 Diag(Loc, diag::err_typecheck_negative_array_size); 6985 else if (Oversized.getBoolValue()) 6986 Diag(Loc, diag::err_array_too_large) 6987 << Oversized.toString(10); 6988 else 6989 Diag(Loc, diag::err_typecheck_field_variable_size); 6990 InvalidDecl = true; 6991 } 6992 } 6993 6994 // Fields can not have abstract class types 6995 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6996 diag::err_abstract_type_in_decl, 6997 AbstractFieldType)) 6998 InvalidDecl = true; 6999 7000 bool ZeroWidth = false; 7001 // If this is declared as a bit-field, check the bit-field. 7002 if (!InvalidDecl && BitWidth && 7003 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 7004 InvalidDecl = true; 7005 BitWidth = 0; 7006 ZeroWidth = false; 7007 } 7008 7009 // Check that 'mutable' is consistent with the type of the declaration. 7010 if (!InvalidDecl && Mutable) { 7011 unsigned DiagID = 0; 7012 if (T->isReferenceType()) 7013 DiagID = diag::err_mutable_reference; 7014 else if (T.isConstQualified()) 7015 DiagID = diag::err_mutable_const; 7016 7017 if (DiagID) { 7018 SourceLocation ErrLoc = Loc; 7019 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 7020 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 7021 Diag(ErrLoc, DiagID); 7022 Mutable = false; 7023 InvalidDecl = true; 7024 } 7025 } 7026 7027 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, 7028 BitWidth, Mutable); 7029 if (InvalidDecl) 7030 NewFD->setInvalidDecl(); 7031 7032 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 7033 Diag(Loc, diag::err_duplicate_member) << II; 7034 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7035 NewFD->setInvalidDecl(); 7036 } 7037 7038 if (!InvalidDecl && getLangOptions().CPlusPlus) { 7039 if (Record->isUnion()) { 7040 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7041 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7042 if (RDecl->getDefinition()) { 7043 // C++ [class.union]p1: An object of a class with a non-trivial 7044 // constructor, a non-trivial copy constructor, a non-trivial 7045 // destructor, or a non-trivial copy assignment operator 7046 // cannot be a member of a union, nor can an array of such 7047 // objects. 7048 // TODO: C++0x alters this restriction significantly. 7049 if (CheckNontrivialField(NewFD)) 7050 NewFD->setInvalidDecl(); 7051 } 7052 } 7053 7054 // C++ [class.union]p1: If a union contains a member of reference type, 7055 // the program is ill-formed. 7056 if (EltTy->isReferenceType()) { 7057 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 7058 << NewFD->getDeclName() << EltTy; 7059 NewFD->setInvalidDecl(); 7060 } 7061 } 7062 } 7063 7064 // FIXME: We need to pass in the attributes given an AST 7065 // representation, not a parser representation. 7066 if (D) 7067 // FIXME: What to pass instead of TUScope? 7068 ProcessDeclAttributes(TUScope, NewFD, *D); 7069 7070 if (T.isObjCGCWeak()) 7071 Diag(Loc, diag::warn_attribute_weak_on_field); 7072 7073 NewFD->setAccess(AS); 7074 return NewFD; 7075} 7076 7077bool Sema::CheckNontrivialField(FieldDecl *FD) { 7078 assert(FD); 7079 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 7080 7081 if (FD->isInvalidDecl()) 7082 return true; 7083 7084 QualType EltTy = Context.getBaseElementType(FD->getType()); 7085 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7086 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7087 if (RDecl->getDefinition()) { 7088 // We check for copy constructors before constructors 7089 // because otherwise we'll never get complaints about 7090 // copy constructors. 7091 7092 CXXSpecialMember member = CXXInvalid; 7093 if (!RDecl->hasTrivialCopyConstructor()) 7094 member = CXXCopyConstructor; 7095 else if (!RDecl->hasTrivialConstructor()) 7096 member = CXXConstructor; 7097 else if (!RDecl->hasTrivialCopyAssignment()) 7098 member = CXXCopyAssignment; 7099 else if (!RDecl->hasTrivialDestructor()) 7100 member = CXXDestructor; 7101 7102 if (member != CXXInvalid) { 7103 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7104 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7105 DiagnoseNontrivial(RT, member); 7106 return true; 7107 } 7108 } 7109 } 7110 7111 return false; 7112} 7113 7114/// DiagnoseNontrivial - Given that a class has a non-trivial 7115/// special member, figure out why. 7116void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7117 QualType QT(T, 0U); 7118 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7119 7120 // Check whether the member was user-declared. 7121 switch (member) { 7122 case CXXInvalid: 7123 break; 7124 7125 case CXXConstructor: 7126 if (RD->hasUserDeclaredConstructor()) { 7127 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7128 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7129 const FunctionDecl *body = 0; 7130 ci->hasBody(body); 7131 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7132 SourceLocation CtorLoc = ci->getLocation(); 7133 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7134 return; 7135 } 7136 } 7137 7138 assert(0 && "found no user-declared constructors"); 7139 return; 7140 } 7141 break; 7142 7143 case CXXCopyConstructor: 7144 if (RD->hasUserDeclaredCopyConstructor()) { 7145 SourceLocation CtorLoc = 7146 RD->getCopyConstructor(Context, 0)->getLocation(); 7147 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7148 return; 7149 } 7150 break; 7151 7152 case CXXCopyAssignment: 7153 if (RD->hasUserDeclaredCopyAssignment()) { 7154 // FIXME: this should use the location of the copy 7155 // assignment, not the type. 7156 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7157 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7158 return; 7159 } 7160 break; 7161 7162 case CXXDestructor: 7163 if (RD->hasUserDeclaredDestructor()) { 7164 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7165 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7166 return; 7167 } 7168 break; 7169 } 7170 7171 typedef CXXRecordDecl::base_class_iterator base_iter; 7172 7173 // Virtual bases and members inhibit trivial copying/construction, 7174 // but not trivial destruction. 7175 if (member != CXXDestructor) { 7176 // Check for virtual bases. vbases includes indirect virtual bases, 7177 // so we just iterate through the direct bases. 7178 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7179 if (bi->isVirtual()) { 7180 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7181 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7182 return; 7183 } 7184 7185 // Check for virtual methods. 7186 typedef CXXRecordDecl::method_iterator meth_iter; 7187 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 7188 ++mi) { 7189 if (mi->isVirtual()) { 7190 SourceLocation MLoc = mi->getSourceRange().getBegin(); 7191 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 7192 return; 7193 } 7194 } 7195 } 7196 7197 bool (CXXRecordDecl::*hasTrivial)() const; 7198 switch (member) { 7199 case CXXConstructor: 7200 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 7201 case CXXCopyConstructor: 7202 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 7203 case CXXCopyAssignment: 7204 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 7205 case CXXDestructor: 7206 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 7207 default: 7208 assert(0 && "unexpected special member"); return; 7209 } 7210 7211 // Check for nontrivial bases (and recurse). 7212 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 7213 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 7214 assert(BaseRT && "Don't know how to handle dependent bases"); 7215 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 7216 if (!(BaseRecTy->*hasTrivial)()) { 7217 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7218 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 7219 DiagnoseNontrivial(BaseRT, member); 7220 return; 7221 } 7222 } 7223 7224 // Check for nontrivial members (and recurse). 7225 typedef RecordDecl::field_iterator field_iter; 7226 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 7227 ++fi) { 7228 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 7229 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 7230 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 7231 7232 if (!(EltRD->*hasTrivial)()) { 7233 SourceLocation FLoc = (*fi)->getLocation(); 7234 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 7235 DiagnoseNontrivial(EltRT, member); 7236 return; 7237 } 7238 } 7239 } 7240 7241 assert(0 && "found no explanation for non-trivial member"); 7242} 7243 7244/// TranslateIvarVisibility - Translate visibility from a token ID to an 7245/// AST enum value. 7246static ObjCIvarDecl::AccessControl 7247TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 7248 switch (ivarVisibility) { 7249 default: assert(0 && "Unknown visitibility kind"); 7250 case tok::objc_private: return ObjCIvarDecl::Private; 7251 case tok::objc_public: return ObjCIvarDecl::Public; 7252 case tok::objc_protected: return ObjCIvarDecl::Protected; 7253 case tok::objc_package: return ObjCIvarDecl::Package; 7254 } 7255} 7256 7257/// ActOnIvar - Each ivar field of an objective-c class is passed into this 7258/// in order to create an IvarDecl object for it. 7259Decl *Sema::ActOnIvar(Scope *S, 7260 SourceLocation DeclStart, 7261 Decl *IntfDecl, 7262 Declarator &D, ExprTy *BitfieldWidth, 7263 tok::ObjCKeywordKind Visibility) { 7264 7265 IdentifierInfo *II = D.getIdentifier(); 7266 Expr *BitWidth = (Expr*)BitfieldWidth; 7267 SourceLocation Loc = DeclStart; 7268 if (II) Loc = D.getIdentifierLoc(); 7269 7270 // FIXME: Unnamed fields can be handled in various different ways, for 7271 // example, unnamed unions inject all members into the struct namespace! 7272 7273 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7274 QualType T = TInfo->getType(); 7275 7276 if (BitWidth) { 7277 // 6.7.2.1p3, 6.7.2.1p4 7278 if (VerifyBitField(Loc, II, T, BitWidth)) { 7279 D.setInvalidType(); 7280 BitWidth = 0; 7281 } 7282 } else { 7283 // Not a bitfield. 7284 7285 // validate II. 7286 7287 } 7288 if (T->isReferenceType()) { 7289 Diag(Loc, diag::err_ivar_reference_type); 7290 D.setInvalidType(); 7291 } 7292 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7293 // than a variably modified type. 7294 else if (T->isVariablyModifiedType()) { 7295 Diag(Loc, diag::err_typecheck_ivar_variable_size); 7296 D.setInvalidType(); 7297 } 7298 7299 // Get the visibility (access control) for this ivar. 7300 ObjCIvarDecl::AccessControl ac = 7301 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 7302 : ObjCIvarDecl::None; 7303 // Must set ivar's DeclContext to its enclosing interface. 7304 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 7305 ObjCContainerDecl *EnclosingContext; 7306 if (ObjCImplementationDecl *IMPDecl = 7307 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7308 if (!LangOpts.ObjCNonFragileABI2) { 7309 // Case of ivar declared in an implementation. Context is that of its class. 7310 EnclosingContext = IMPDecl->getClassInterface(); 7311 assert(EnclosingContext && "Implementation has no class interface!"); 7312 } 7313 else 7314 EnclosingContext = EnclosingDecl; 7315 } else { 7316 if (ObjCCategoryDecl *CDecl = 7317 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7318 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 7319 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 7320 return 0; 7321 } 7322 } 7323 EnclosingContext = EnclosingDecl; 7324 } 7325 7326 // Construct the decl. 7327 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, 7328 DeclStart, Loc, II, T, 7329 TInfo, ac, (Expr *)BitfieldWidth); 7330 7331 if (II) { 7332 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 7333 ForRedeclaration); 7334 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 7335 && !isa<TagDecl>(PrevDecl)) { 7336 Diag(Loc, diag::err_duplicate_member) << II; 7337 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7338 NewID->setInvalidDecl(); 7339 } 7340 } 7341 7342 // Process attributes attached to the ivar. 7343 ProcessDeclAttributes(S, NewID, D); 7344 7345 if (D.isInvalidType()) 7346 NewID->setInvalidDecl(); 7347 7348 if (II) { 7349 // FIXME: When interfaces are DeclContexts, we'll need to add 7350 // these to the interface. 7351 S->AddDecl(NewID); 7352 IdResolver.AddDecl(NewID); 7353 } 7354 7355 return NewID; 7356} 7357 7358/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 7359/// class and class extensions. For every class @interface and class 7360/// extension @interface, if the last ivar is a bitfield of any type, 7361/// then add an implicit `char :0` ivar to the end of that interface. 7362void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 7363 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 7364 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 7365 return; 7366 7367 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 7368 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 7369 7370 if (!Ivar->isBitField()) 7371 return; 7372 uint64_t BitFieldSize = 7373 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 7374 if (BitFieldSize == 0) 7375 return; 7376 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 7377 if (!ID) { 7378 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7379 if (!CD->IsClassExtension()) 7380 return; 7381 } 7382 // No need to add this to end of @implementation. 7383 else 7384 return; 7385 } 7386 // All conditions are met. Add a new bitfield to the tail end of ivars. 7387 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 7388 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 7389 7390 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 7391 DeclLoc, DeclLoc, 0, 7392 Context.CharTy, 7393 Context.CreateTypeSourceInfo(Context.CharTy), 7394 ObjCIvarDecl::Private, BW, 7395 true); 7396 AllIvarDecls.push_back(Ivar); 7397} 7398 7399void Sema::ActOnFields(Scope* S, 7400 SourceLocation RecLoc, Decl *EnclosingDecl, 7401 Decl **Fields, unsigned NumFields, 7402 SourceLocation LBrac, SourceLocation RBrac, 7403 AttributeList *Attr) { 7404 assert(EnclosingDecl && "missing record or interface decl"); 7405 7406 // If the decl this is being inserted into is invalid, then it may be a 7407 // redeclaration or some other bogus case. Don't try to add fields to it. 7408 if (EnclosingDecl->isInvalidDecl()) { 7409 // FIXME: Deallocate fields? 7410 return; 7411 } 7412 7413 7414 // Verify that all the fields are okay. 7415 unsigned NumNamedMembers = 0; 7416 llvm::SmallVector<FieldDecl*, 32> RecFields; 7417 7418 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 7419 for (unsigned i = 0; i != NumFields; ++i) { 7420 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 7421 7422 // Get the type for the field. 7423 const Type *FDTy = FD->getType().getTypePtr(); 7424 7425 if (!FD->isAnonymousStructOrUnion()) { 7426 // Remember all fields written by the user. 7427 RecFields.push_back(FD); 7428 } 7429 7430 // If the field is already invalid for some reason, don't emit more 7431 // diagnostics about it. 7432 if (FD->isInvalidDecl()) { 7433 EnclosingDecl->setInvalidDecl(); 7434 continue; 7435 } 7436 7437 // C99 6.7.2.1p2: 7438 // A structure or union shall not contain a member with 7439 // incomplete or function type (hence, a structure shall not 7440 // contain an instance of itself, but may contain a pointer to 7441 // an instance of itself), except that the last member of a 7442 // structure with more than one named member may have incomplete 7443 // array type; such a structure (and any union containing, 7444 // possibly recursively, a member that is such a structure) 7445 // shall not be a member of a structure or an element of an 7446 // array. 7447 if (FDTy->isFunctionType()) { 7448 // Field declared as a function. 7449 Diag(FD->getLocation(), diag::err_field_declared_as_function) 7450 << FD->getDeclName(); 7451 FD->setInvalidDecl(); 7452 EnclosingDecl->setInvalidDecl(); 7453 continue; 7454 } else if (FDTy->isIncompleteArrayType() && Record && 7455 ((i == NumFields - 1 && !Record->isUnion()) || 7456 ((getLangOptions().Microsoft || getLangOptions().CPlusPlus) && 7457 (i == NumFields - 1 || Record->isUnion())))) { 7458 // Flexible array member. 7459 // Microsoft and g++ is more permissive regarding flexible array. 7460 // It will accept flexible array in union and also 7461 // as the sole element of a struct/class. 7462 if (getLangOptions().Microsoft) { 7463 if (Record->isUnion()) 7464 Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) 7465 << FD->getDeclName(); 7466 else if (NumFields == 1) 7467 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) 7468 << FD->getDeclName() << Record->getTagKind(); 7469 } else if (getLangOptions().CPlusPlus) { 7470 if (Record->isUnion()) 7471 Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) 7472 << FD->getDeclName(); 7473 else if (NumFields == 1) 7474 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) 7475 << FD->getDeclName() << Record->getTagKind(); 7476 } else if (NumNamedMembers < 1) { 7477 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 7478 << FD->getDeclName(); 7479 FD->setInvalidDecl(); 7480 EnclosingDecl->setInvalidDecl(); 7481 continue; 7482 } 7483 if (!FD->getType()->isDependentType() && 7484 !Context.getBaseElementType(FD->getType())->isPODType()) { 7485 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 7486 << FD->getDeclName() << FD->getType(); 7487 FD->setInvalidDecl(); 7488 EnclosingDecl->setInvalidDecl(); 7489 continue; 7490 } 7491 // Okay, we have a legal flexible array member at the end of the struct. 7492 if (Record) 7493 Record->setHasFlexibleArrayMember(true); 7494 } else if (!FDTy->isDependentType() && 7495 RequireCompleteType(FD->getLocation(), FD->getType(), 7496 diag::err_field_incomplete)) { 7497 // Incomplete type 7498 FD->setInvalidDecl(); 7499 EnclosingDecl->setInvalidDecl(); 7500 continue; 7501 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 7502 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 7503 // If this is a member of a union, then entire union becomes "flexible". 7504 if (Record && Record->isUnion()) { 7505 Record->setHasFlexibleArrayMember(true); 7506 } else { 7507 // If this is a struct/class and this is not the last element, reject 7508 // it. Note that GCC supports variable sized arrays in the middle of 7509 // structures. 7510 if (i != NumFields-1) 7511 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 7512 << FD->getDeclName() << FD->getType(); 7513 else { 7514 // We support flexible arrays at the end of structs in 7515 // other structs as an extension. 7516 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 7517 << FD->getDeclName(); 7518 if (Record) 7519 Record->setHasFlexibleArrayMember(true); 7520 } 7521 } 7522 } 7523 if (Record && FDTTy->getDecl()->hasObjectMember()) 7524 Record->setHasObjectMember(true); 7525 } else if (FDTy->isObjCObjectType()) { 7526 /// A field cannot be an Objective-c object 7527 Diag(FD->getLocation(), diag::err_statically_allocated_object); 7528 FD->setInvalidDecl(); 7529 EnclosingDecl->setInvalidDecl(); 7530 continue; 7531 } else if (getLangOptions().ObjC1 && 7532 getLangOptions().getGCMode() != LangOptions::NonGC && 7533 Record && 7534 (FD->getType()->isObjCObjectPointerType() || 7535 FD->getType().isObjCGCStrong())) 7536 Record->setHasObjectMember(true); 7537 else if (Context.getAsArrayType(FD->getType())) { 7538 QualType BaseType = Context.getBaseElementType(FD->getType()); 7539 if (Record && BaseType->isRecordType() && 7540 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 7541 Record->setHasObjectMember(true); 7542 } 7543 // Keep track of the number of named members. 7544 if (FD->getIdentifier()) 7545 ++NumNamedMembers; 7546 } 7547 7548 // Okay, we successfully defined 'Record'. 7549 if (Record) { 7550 bool Completed = false; 7551 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 7552 if (!CXXRecord->isInvalidDecl()) { 7553 // Set access bits correctly on the directly-declared conversions. 7554 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 7555 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 7556 I != E; ++I) 7557 Convs->setAccess(I, (*I)->getAccess()); 7558 7559 if (!CXXRecord->isDependentType()) { 7560 // Add any implicitly-declared members to this class. 7561 AddImplicitlyDeclaredMembersToClass(CXXRecord); 7562 7563 // If we have virtual base classes, we may end up finding multiple 7564 // final overriders for a given virtual function. Check for this 7565 // problem now. 7566 if (CXXRecord->getNumVBases()) { 7567 CXXFinalOverriderMap FinalOverriders; 7568 CXXRecord->getFinalOverriders(FinalOverriders); 7569 7570 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 7571 MEnd = FinalOverriders.end(); 7572 M != MEnd; ++M) { 7573 for (OverridingMethods::iterator SO = M->second.begin(), 7574 SOEnd = M->second.end(); 7575 SO != SOEnd; ++SO) { 7576 assert(SO->second.size() > 0 && 7577 "Virtual function without overridding functions?"); 7578 if (SO->second.size() == 1) 7579 continue; 7580 7581 // C++ [class.virtual]p2: 7582 // In a derived class, if a virtual member function of a base 7583 // class subobject has more than one final overrider the 7584 // program is ill-formed. 7585 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 7586 << (NamedDecl *)M->first << Record; 7587 Diag(M->first->getLocation(), 7588 diag::note_overridden_virtual_function); 7589 for (OverridingMethods::overriding_iterator 7590 OM = SO->second.begin(), 7591 OMEnd = SO->second.end(); 7592 OM != OMEnd; ++OM) 7593 Diag(OM->Method->getLocation(), diag::note_final_overrider) 7594 << (NamedDecl *)M->first << OM->Method->getParent(); 7595 7596 Record->setInvalidDecl(); 7597 } 7598 } 7599 CXXRecord->completeDefinition(&FinalOverriders); 7600 Completed = true; 7601 } 7602 } 7603 } 7604 } 7605 7606 if (!Completed) 7607 Record->completeDefinition(); 7608 } else { 7609 ObjCIvarDecl **ClsFields = 7610 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 7611 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 7612 ID->setLocEnd(RBrac); 7613 // Add ivar's to class's DeclContext. 7614 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7615 ClsFields[i]->setLexicalDeclContext(ID); 7616 ID->addDecl(ClsFields[i]); 7617 } 7618 // Must enforce the rule that ivars in the base classes may not be 7619 // duplicates. 7620 if (ID->getSuperClass()) 7621 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 7622 } else if (ObjCImplementationDecl *IMPDecl = 7623 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7624 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 7625 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 7626 // Ivar declared in @implementation never belongs to the implementation. 7627 // Only it is in implementation's lexical context. 7628 ClsFields[I]->setLexicalDeclContext(IMPDecl); 7629 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 7630 } else if (ObjCCategoryDecl *CDecl = 7631 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7632 // case of ivars in class extension; all other cases have been 7633 // reported as errors elsewhere. 7634 // FIXME. Class extension does not have a LocEnd field. 7635 // CDecl->setLocEnd(RBrac); 7636 // Add ivar's to class extension's DeclContext. 7637 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7638 ClsFields[i]->setLexicalDeclContext(CDecl); 7639 CDecl->addDecl(ClsFields[i]); 7640 } 7641 } 7642 } 7643 7644 if (Attr) 7645 ProcessDeclAttributeList(S, Record, Attr); 7646 7647 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 7648 // set the visibility of this record. 7649 if (Record && !Record->getDeclContext()->isRecord()) 7650 AddPushedVisibilityAttribute(Record); 7651} 7652 7653/// \brief Determine whether the given integral value is representable within 7654/// the given type T. 7655static bool isRepresentableIntegerValue(ASTContext &Context, 7656 llvm::APSInt &Value, 7657 QualType T) { 7658 assert(T->isIntegralType(Context) && "Integral type required!"); 7659 unsigned BitWidth = Context.getIntWidth(T); 7660 7661 if (Value.isUnsigned() || Value.isNonNegative()) { 7662 if (T->isSignedIntegerType()) 7663 --BitWidth; 7664 return Value.getActiveBits() <= BitWidth; 7665 } 7666 return Value.getMinSignedBits() <= BitWidth; 7667} 7668 7669// \brief Given an integral type, return the next larger integral type 7670// (or a NULL type of no such type exists). 7671static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 7672 // FIXME: Int128/UInt128 support, which also needs to be introduced into 7673 // enum checking below. 7674 assert(T->isIntegralType(Context) && "Integral type required!"); 7675 const unsigned NumTypes = 4; 7676 QualType SignedIntegralTypes[NumTypes] = { 7677 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 7678 }; 7679 QualType UnsignedIntegralTypes[NumTypes] = { 7680 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 7681 Context.UnsignedLongLongTy 7682 }; 7683 7684 unsigned BitWidth = Context.getTypeSize(T); 7685 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7686 : UnsignedIntegralTypes; 7687 for (unsigned I = 0; I != NumTypes; ++I) 7688 if (Context.getTypeSize(Types[I]) > BitWidth) 7689 return Types[I]; 7690 7691 return QualType(); 7692} 7693 7694EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7695 EnumConstantDecl *LastEnumConst, 7696 SourceLocation IdLoc, 7697 IdentifierInfo *Id, 7698 Expr *Val) { 7699 unsigned IntWidth = Context.Target.getIntWidth(); 7700 llvm::APSInt EnumVal(IntWidth); 7701 QualType EltTy; 7702 7703 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 7704 Val = 0; 7705 7706 if (Val) { 7707 if (Enum->isDependentType() || Val->isTypeDependent()) 7708 EltTy = Context.DependentTy; 7709 else { 7710 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7711 SourceLocation ExpLoc; 7712 if (!Val->isValueDependent() && 7713 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7714 Val = 0; 7715 } else { 7716 if (!getLangOptions().CPlusPlus) { 7717 // C99 6.7.2.2p2: 7718 // The expression that defines the value of an enumeration constant 7719 // shall be an integer constant expression that has a value 7720 // representable as an int. 7721 7722 // Complain if the value is not representable in an int. 7723 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7724 Diag(IdLoc, diag::ext_enum_value_not_int) 7725 << EnumVal.toString(10) << Val->getSourceRange() 7726 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7727 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7728 // Force the type of the expression to 'int'. 7729 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 7730 } 7731 } 7732 7733 if (Enum->isFixed()) { 7734 EltTy = Enum->getIntegerType(); 7735 7736 // C++0x [dcl.enum]p5: 7737 // ... if the initializing value of an enumerator cannot be 7738 // represented by the underlying type, the program is ill-formed. 7739 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7740 if (getLangOptions().Microsoft) { 7741 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 7742 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7743 } else 7744 Diag(IdLoc, diag::err_enumerator_too_large) 7745 << EltTy; 7746 } else 7747 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7748 } 7749 else { 7750 // C++0x [dcl.enum]p5: 7751 // If the underlying type is not fixed, the type of each enumerator 7752 // is the type of its initializing value: 7753 // - If an initializer is specified for an enumerator, the 7754 // initializing value has the same type as the expression. 7755 EltTy = Val->getType(); 7756 } 7757 } 7758 } 7759 } 7760 7761 if (!Val) { 7762 if (Enum->isDependentType()) 7763 EltTy = Context.DependentTy; 7764 else if (!LastEnumConst) { 7765 // C++0x [dcl.enum]p5: 7766 // If the underlying type is not fixed, the type of each enumerator 7767 // is the type of its initializing value: 7768 // - If no initializer is specified for the first enumerator, the 7769 // initializing value has an unspecified integral type. 7770 // 7771 // GCC uses 'int' for its unspecified integral type, as does 7772 // C99 6.7.2.2p3. 7773 if (Enum->isFixed()) { 7774 EltTy = Enum->getIntegerType(); 7775 } 7776 else { 7777 EltTy = Context.IntTy; 7778 } 7779 } else { 7780 // Assign the last value + 1. 7781 EnumVal = LastEnumConst->getInitVal(); 7782 ++EnumVal; 7783 EltTy = LastEnumConst->getType(); 7784 7785 // Check for overflow on increment. 7786 if (EnumVal < LastEnumConst->getInitVal()) { 7787 // C++0x [dcl.enum]p5: 7788 // If the underlying type is not fixed, the type of each enumerator 7789 // is the type of its initializing value: 7790 // 7791 // - Otherwise the type of the initializing value is the same as 7792 // the type of the initializing value of the preceding enumerator 7793 // unless the incremented value is not representable in that type, 7794 // in which case the type is an unspecified integral type 7795 // sufficient to contain the incremented value. If no such type 7796 // exists, the program is ill-formed. 7797 QualType T = getNextLargerIntegralType(Context, EltTy); 7798 if (T.isNull() || Enum->isFixed()) { 7799 // There is no integral type larger enough to represent this 7800 // value. Complain, then allow the value to wrap around. 7801 EnumVal = LastEnumConst->getInitVal(); 7802 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 7803 ++EnumVal; 7804 if (Enum->isFixed()) 7805 // When the underlying type is fixed, this is ill-formed. 7806 Diag(IdLoc, diag::err_enumerator_wrapped) 7807 << EnumVal.toString(10) 7808 << EltTy; 7809 else 7810 Diag(IdLoc, diag::warn_enumerator_too_large) 7811 << EnumVal.toString(10); 7812 } else { 7813 EltTy = T; 7814 } 7815 7816 // Retrieve the last enumerator's value, extent that type to the 7817 // type that is supposed to be large enough to represent the incremented 7818 // value, then increment. 7819 EnumVal = LastEnumConst->getInitVal(); 7820 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7821 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7822 ++EnumVal; 7823 7824 // If we're not in C++, diagnose the overflow of enumerator values, 7825 // which in C99 means that the enumerator value is not representable in 7826 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7827 // permits enumerator values that are representable in some larger 7828 // integral type. 7829 if (!getLangOptions().CPlusPlus && !T.isNull()) 7830 Diag(IdLoc, diag::warn_enum_value_overflow); 7831 } else if (!getLangOptions().CPlusPlus && 7832 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7833 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7834 Diag(IdLoc, diag::ext_enum_value_not_int) 7835 << EnumVal.toString(10) << 1; 7836 } 7837 } 7838 } 7839 7840 if (!EltTy->isDependentType()) { 7841 // Make the enumerator value match the signedness and size of the 7842 // enumerator's type. 7843 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7844 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7845 } 7846 7847 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7848 Val, EnumVal); 7849} 7850 7851 7852Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 7853 SourceLocation IdLoc, IdentifierInfo *Id, 7854 AttributeList *Attr, 7855 SourceLocation EqualLoc, ExprTy *val) { 7856 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7857 EnumConstantDecl *LastEnumConst = 7858 cast_or_null<EnumConstantDecl>(lastEnumConst); 7859 Expr *Val = static_cast<Expr*>(val); 7860 7861 // The scope passed in may not be a decl scope. Zip up the scope tree until 7862 // we find one that is. 7863 S = getNonFieldDeclScope(S); 7864 7865 // Verify that there isn't already something declared with this name in this 7866 // scope. 7867 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7868 ForRedeclaration); 7869 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7870 // Maybe we will complain about the shadowed template parameter. 7871 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7872 // Just pretend that we didn't see the previous declaration. 7873 PrevDecl = 0; 7874 } 7875 7876 if (PrevDecl) { 7877 // When in C++, we may get a TagDecl with the same name; in this case the 7878 // enum constant will 'hide' the tag. 7879 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7880 "Received TagDecl when not in C++!"); 7881 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7882 if (isa<EnumConstantDecl>(PrevDecl)) 7883 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7884 else 7885 Diag(IdLoc, diag::err_redefinition) << Id; 7886 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7887 return 0; 7888 } 7889 } 7890 7891 // C++ [class.mem]p13: 7892 // If T is the name of a class, then each of the following shall have a 7893 // name different from T: 7894 // - every enumerator of every member of class T that is an enumerated 7895 // type 7896 if (CXXRecordDecl *Record 7897 = dyn_cast<CXXRecordDecl>( 7898 TheEnumDecl->getDeclContext()->getRedeclContext())) 7899 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7900 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7901 7902 EnumConstantDecl *New = 7903 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 7904 7905 if (New) { 7906 // Process attributes. 7907 if (Attr) ProcessDeclAttributeList(S, New, Attr); 7908 7909 // Register this decl in the current scope stack. 7910 New->setAccess(TheEnumDecl->getAccess()); 7911 PushOnScopeChains(New, S); 7912 } 7913 7914 return New; 7915} 7916 7917void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7918 SourceLocation RBraceLoc, Decl *EnumDeclX, 7919 Decl **Elements, unsigned NumElements, 7920 Scope *S, AttributeList *Attr) { 7921 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7922 QualType EnumType = Context.getTypeDeclType(Enum); 7923 7924 if (Attr) 7925 ProcessDeclAttributeList(S, Enum, Attr); 7926 7927 if (Enum->isDependentType()) { 7928 for (unsigned i = 0; i != NumElements; ++i) { 7929 EnumConstantDecl *ECD = 7930 cast_or_null<EnumConstantDecl>(Elements[i]); 7931 if (!ECD) continue; 7932 7933 ECD->setType(EnumType); 7934 } 7935 7936 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7937 return; 7938 } 7939 7940 // TODO: If the result value doesn't fit in an int, it must be a long or long 7941 // long value. ISO C does not support this, but GCC does as an extension, 7942 // emit a warning. 7943 unsigned IntWidth = Context.Target.getIntWidth(); 7944 unsigned CharWidth = Context.Target.getCharWidth(); 7945 unsigned ShortWidth = Context.Target.getShortWidth(); 7946 7947 // Verify that all the values are okay, compute the size of the values, and 7948 // reverse the list. 7949 unsigned NumNegativeBits = 0; 7950 unsigned NumPositiveBits = 0; 7951 7952 // Keep track of whether all elements have type int. 7953 bool AllElementsInt = true; 7954 7955 for (unsigned i = 0; i != NumElements; ++i) { 7956 EnumConstantDecl *ECD = 7957 cast_or_null<EnumConstantDecl>(Elements[i]); 7958 if (!ECD) continue; // Already issued a diagnostic. 7959 7960 const llvm::APSInt &InitVal = ECD->getInitVal(); 7961 7962 // Keep track of the size of positive and negative values. 7963 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7964 NumPositiveBits = std::max(NumPositiveBits, 7965 (unsigned)InitVal.getActiveBits()); 7966 else 7967 NumNegativeBits = std::max(NumNegativeBits, 7968 (unsigned)InitVal.getMinSignedBits()); 7969 7970 // Keep track of whether every enum element has type int (very commmon). 7971 if (AllElementsInt) 7972 AllElementsInt = ECD->getType() == Context.IntTy; 7973 } 7974 7975 // Figure out the type that should be used for this enum. 7976 QualType BestType; 7977 unsigned BestWidth; 7978 7979 // C++0x N3000 [conv.prom]p3: 7980 // An rvalue of an unscoped enumeration type whose underlying 7981 // type is not fixed can be converted to an rvalue of the first 7982 // of the following types that can represent all the values of 7983 // the enumeration: int, unsigned int, long int, unsigned long 7984 // int, long long int, or unsigned long long int. 7985 // C99 6.4.4.3p2: 7986 // An identifier declared as an enumeration constant has type int. 7987 // The C99 rule is modified by a gcc extension 7988 QualType BestPromotionType; 7989 7990 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7991 // -fshort-enums is the equivalent to specifying the packed attribute on all 7992 // enum definitions. 7993 if (LangOpts.ShortEnums) 7994 Packed = true; 7995 7996 if (Enum->isFixed()) { 7997 BestType = BestPromotionType = Enum->getIntegerType(); 7998 // We don't need to set BestWidth, because BestType is going to be the type 7999 // of the enumerators, but we do anyway because otherwise some compilers 8000 // warn that it might be used uninitialized. 8001 BestWidth = CharWidth; 8002 } 8003 else if (NumNegativeBits) { 8004 // If there is a negative value, figure out the smallest integer type (of 8005 // int/long/longlong) that fits. 8006 // If it's packed, check also if it fits a char or a short. 8007 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 8008 BestType = Context.SignedCharTy; 8009 BestWidth = CharWidth; 8010 } else if (Packed && NumNegativeBits <= ShortWidth && 8011 NumPositiveBits < ShortWidth) { 8012 BestType = Context.ShortTy; 8013 BestWidth = ShortWidth; 8014 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 8015 BestType = Context.IntTy; 8016 BestWidth = IntWidth; 8017 } else { 8018 BestWidth = Context.Target.getLongWidth(); 8019 8020 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 8021 BestType = Context.LongTy; 8022 } else { 8023 BestWidth = Context.Target.getLongLongWidth(); 8024 8025 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 8026 Diag(Enum->getLocation(), diag::warn_enum_too_large); 8027 BestType = Context.LongLongTy; 8028 } 8029 } 8030 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 8031 } else { 8032 // If there is no negative value, figure out the smallest type that fits 8033 // all of the enumerator values. 8034 // If it's packed, check also if it fits a char or a short. 8035 if (Packed && NumPositiveBits <= CharWidth) { 8036 BestType = Context.UnsignedCharTy; 8037 BestPromotionType = Context.IntTy; 8038 BestWidth = CharWidth; 8039 } else if (Packed && NumPositiveBits <= ShortWidth) { 8040 BestType = Context.UnsignedShortTy; 8041 BestPromotionType = Context.IntTy; 8042 BestWidth = ShortWidth; 8043 } else if (NumPositiveBits <= IntWidth) { 8044 BestType = Context.UnsignedIntTy; 8045 BestWidth = IntWidth; 8046 BestPromotionType 8047 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8048 ? Context.UnsignedIntTy : Context.IntTy; 8049 } else if (NumPositiveBits <= 8050 (BestWidth = Context.Target.getLongWidth())) { 8051 BestType = Context.UnsignedLongTy; 8052 BestPromotionType 8053 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8054 ? Context.UnsignedLongTy : Context.LongTy; 8055 } else { 8056 BestWidth = Context.Target.getLongLongWidth(); 8057 assert(NumPositiveBits <= BestWidth && 8058 "How could an initializer get larger than ULL?"); 8059 BestType = Context.UnsignedLongLongTy; 8060 BestPromotionType 8061 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8062 ? Context.UnsignedLongLongTy : Context.LongLongTy; 8063 } 8064 } 8065 8066 // Loop over all of the enumerator constants, changing their types to match 8067 // the type of the enum if needed. 8068 for (unsigned i = 0; i != NumElements; ++i) { 8069 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 8070 if (!ECD) continue; // Already issued a diagnostic. 8071 8072 // Standard C says the enumerators have int type, but we allow, as an 8073 // extension, the enumerators to be larger than int size. If each 8074 // enumerator value fits in an int, type it as an int, otherwise type it the 8075 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 8076 // that X has type 'int', not 'unsigned'. 8077 8078 // Determine whether the value fits into an int. 8079 llvm::APSInt InitVal = ECD->getInitVal(); 8080 8081 // If it fits into an integer type, force it. Otherwise force it to match 8082 // the enum decl type. 8083 QualType NewTy; 8084 unsigned NewWidth; 8085 bool NewSign; 8086 if (!getLangOptions().CPlusPlus && 8087 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 8088 NewTy = Context.IntTy; 8089 NewWidth = IntWidth; 8090 NewSign = true; 8091 } else if (ECD->getType() == BestType) { 8092 // Already the right type! 8093 if (getLangOptions().CPlusPlus) 8094 // C++ [dcl.enum]p4: Following the closing brace of an 8095 // enum-specifier, each enumerator has the type of its 8096 // enumeration. 8097 ECD->setType(EnumType); 8098 continue; 8099 } else { 8100 NewTy = BestType; 8101 NewWidth = BestWidth; 8102 NewSign = BestType->isSignedIntegerType(); 8103 } 8104 8105 // Adjust the APSInt value. 8106 InitVal = InitVal.extOrTrunc(NewWidth); 8107 InitVal.setIsSigned(NewSign); 8108 ECD->setInitVal(InitVal); 8109 8110 // Adjust the Expr initializer and type. 8111 if (ECD->getInitExpr() && 8112 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 8113 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 8114 CK_IntegralCast, 8115 ECD->getInitExpr(), 8116 /*base paths*/ 0, 8117 VK_RValue)); 8118 if (getLangOptions().CPlusPlus) 8119 // C++ [dcl.enum]p4: Following the closing brace of an 8120 // enum-specifier, each enumerator has the type of its 8121 // enumeration. 8122 ECD->setType(EnumType); 8123 else 8124 ECD->setType(NewTy); 8125 } 8126 8127 Enum->completeDefinition(BestType, BestPromotionType, 8128 NumPositiveBits, NumNegativeBits); 8129} 8130 8131Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 8132 SourceLocation StartLoc, 8133 SourceLocation EndLoc) { 8134 StringLiteral *AsmString = cast<StringLiteral>(expr); 8135 8136 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 8137 AsmString, StartLoc, 8138 EndLoc); 8139 CurContext->addDecl(New); 8140 return New; 8141} 8142 8143void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 8144 SourceLocation PragmaLoc, 8145 SourceLocation NameLoc) { 8146 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 8147 8148 if (PrevDecl) { 8149 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 8150 } else { 8151 (void)WeakUndeclaredIdentifiers.insert( 8152 std::pair<IdentifierInfo*,WeakInfo> 8153 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 8154 } 8155} 8156 8157void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 8158 IdentifierInfo* AliasName, 8159 SourceLocation PragmaLoc, 8160 SourceLocation NameLoc, 8161 SourceLocation AliasNameLoc) { 8162 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 8163 LookupOrdinaryName); 8164 WeakInfo W = WeakInfo(Name, NameLoc); 8165 8166 if (PrevDecl) { 8167 if (!PrevDecl->hasAttr<AliasAttr>()) 8168 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 8169 DeclApplyPragmaWeak(TUScope, ND, W); 8170 } else { 8171 (void)WeakUndeclaredIdentifiers.insert( 8172 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 8173 } 8174} 8175