SemaDecl.cpp revision 429bb276991ff2dbc7c5b438828b9b7737cb15eb
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/EvaluatedExprVisitor.h" 29#include "clang/AST/ExprCXX.h" 30#include "clang/AST/StmtCXX.h" 31#include "clang/AST/CharUnits.h" 32#include "clang/Sema/DeclSpec.h" 33#include "clang/Sema/ParsedTemplate.h" 34#include "clang/Parse/ParseDiagnostic.h" 35#include "clang/Basic/PartialDiagnostic.h" 36#include "clang/Basic/SourceManager.h" 37#include "clang/Basic/TargetInfo.h" 38// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 39#include "clang/Lex/Preprocessor.h" 40#include "clang/Lex/HeaderSearch.h" 41#include "llvm/ADT/Triple.h" 42#include <algorithm> 43#include <cstring> 44#include <functional> 45using namespace clang; 46using namespace sema; 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, bool HasTrailingDot, 66 ParsedType ObjectTypePtr, 67 bool WantNontrivialTypeSourceInfo) { 68 // Determine where we will perform name lookup. 69 DeclContext *LookupCtx = 0; 70 if (ObjectTypePtr) { 71 QualType ObjectType = ObjectTypePtr.get(); 72 if (ObjectType->isRecordType()) 73 LookupCtx = computeDeclContext(ObjectType); 74 } else if (SS && SS->isNotEmpty()) { 75 LookupCtx = computeDeclContext(*SS, false); 76 77 if (!LookupCtx) { 78 if (isDependentScopeSpecifier(*SS)) { 79 // C++ [temp.res]p3: 80 // A qualified-id that refers to a type and in which the 81 // nested-name-specifier depends on a template-parameter (14.6.2) 82 // shall be prefixed by the keyword typename to indicate that the 83 // qualified-id denotes a type, forming an 84 // elaborated-type-specifier (7.1.5.3). 85 // 86 // We therefore do not perform any name lookup if the result would 87 // refer to a member of an unknown specialization. 88 if (!isClassName) 89 return ParsedType(); 90 91 // We know from the grammar that this name refers to a type, 92 // so build a dependent node to describe the type. 93 if (WantNontrivialTypeSourceInfo) 94 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 95 96 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 97 QualType T = 98 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 99 II, NameLoc); 100 101 return ParsedType::make(T); 102 } 103 104 return ParsedType(); 105 } 106 107 if (!LookupCtx->isDependentContext() && 108 RequireCompleteDeclContext(*SS, LookupCtx)) 109 return ParsedType(); 110 } 111 112 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 113 // lookup for class-names. 114 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 115 LookupOrdinaryName; 116 LookupResult Result(*this, &II, NameLoc, Kind); 117 if (LookupCtx) { 118 // Perform "qualified" name lookup into the declaration context we 119 // computed, which is either the type of the base of a member access 120 // expression or the declaration context associated with a prior 121 // nested-name-specifier. 122 LookupQualifiedName(Result, LookupCtx); 123 124 if (ObjectTypePtr && Result.empty()) { 125 // C++ [basic.lookup.classref]p3: 126 // If the unqualified-id is ~type-name, the type-name is looked up 127 // in the context of the entire postfix-expression. If the type T of 128 // the object expression is of a class type C, the type-name is also 129 // looked up in the scope of class C. At least one of the lookups shall 130 // find a name that refers to (possibly cv-qualified) T. 131 LookupName(Result, S); 132 } 133 } else { 134 // Perform unqualified name lookup. 135 LookupName(Result, S); 136 } 137 138 NamedDecl *IIDecl = 0; 139 switch (Result.getResultKind()) { 140 case LookupResult::NotFound: 141 case LookupResult::NotFoundInCurrentInstantiation: 142 case LookupResult::FoundOverloaded: 143 case LookupResult::FoundUnresolvedValue: 144 Result.suppressDiagnostics(); 145 return ParsedType(); 146 147 case LookupResult::Ambiguous: 148 // Recover from type-hiding ambiguities by hiding the type. We'll 149 // do the lookup again when looking for an object, and we can 150 // diagnose the error then. If we don't do this, then the error 151 // about hiding the type will be immediately followed by an error 152 // that only makes sense if the identifier was treated like a type. 153 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 154 Result.suppressDiagnostics(); 155 return ParsedType(); 156 } 157 158 // Look to see if we have a type anywhere in the list of results. 159 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 160 Res != ResEnd; ++Res) { 161 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 162 if (!IIDecl || 163 (*Res)->getLocation().getRawEncoding() < 164 IIDecl->getLocation().getRawEncoding()) 165 IIDecl = *Res; 166 } 167 } 168 169 if (!IIDecl) { 170 // None of the entities we found is a type, so there is no way 171 // to even assume that the result is a type. In this case, don't 172 // complain about the ambiguity. The parser will either try to 173 // perform this lookup again (e.g., as an object name), which 174 // will produce the ambiguity, or will complain that it expected 175 // a type name. 176 Result.suppressDiagnostics(); 177 return ParsedType(); 178 } 179 180 // We found a type within the ambiguous lookup; diagnose the 181 // ambiguity and then return that type. This might be the right 182 // answer, or it might not be, but it suppresses any attempt to 183 // perform the name lookup again. 184 break; 185 186 case LookupResult::Found: 187 IIDecl = Result.getFoundDecl(); 188 break; 189 } 190 191 assert(IIDecl && "Didn't find decl"); 192 193 QualType T; 194 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 195 DiagnoseUseOfDecl(IIDecl, NameLoc); 196 197 if (T.isNull()) 198 T = Context.getTypeDeclType(TD); 199 200 if (SS && SS->isNotEmpty()) { 201 if (WantNontrivialTypeSourceInfo) { 202 // Construct a type with type-source information. 203 TypeLocBuilder Builder; 204 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 205 206 T = getElaboratedType(ETK_None, *SS, T); 207 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 208 ElabTL.setKeywordLoc(SourceLocation()); 209 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 210 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 211 } else { 212 T = getElaboratedType(ETK_None, *SS, T); 213 } 214 } 215 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 216 (void)DiagnoseUseOfDecl(IDecl, NameLoc); 217 if (!HasTrailingDot) 218 T = Context.getObjCInterfaceType(IDecl); 219 } 220 221 if (T.isNull()) { 222 // If it's not plausibly a type, suppress diagnostics. 223 Result.suppressDiagnostics(); 224 return ParsedType(); 225 } 226 return ParsedType::make(T); 227} 228 229/// isTagName() - This method is called *for error recovery purposes only* 230/// to determine if the specified name is a valid tag name ("struct foo"). If 231/// so, this returns the TST for the tag corresponding to it (TST_enum, 232/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 233/// where the user forgot to specify the tag. 234DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 235 // Do a tag name lookup in this scope. 236 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 237 LookupName(R, S, false); 238 R.suppressDiagnostics(); 239 if (R.getResultKind() == LookupResult::Found) 240 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 241 switch (TD->getTagKind()) { 242 default: return DeclSpec::TST_unspecified; 243 case TTK_Struct: return DeclSpec::TST_struct; 244 case TTK_Union: return DeclSpec::TST_union; 245 case TTK_Class: return DeclSpec::TST_class; 246 case TTK_Enum: return DeclSpec::TST_enum; 247 } 248 } 249 250 return DeclSpec::TST_unspecified; 251} 252 253bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 254 SourceLocation IILoc, 255 Scope *S, 256 CXXScopeSpec *SS, 257 ParsedType &SuggestedType) { 258 // We don't have anything to suggest (yet). 259 SuggestedType = ParsedType(); 260 261 // There may have been a typo in the name of the type. Look up typo 262 // results, in case we have something that we can suggest. 263 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 264 NotForRedeclaration); 265 266 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 267 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 268 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 269 !Result->isInvalidDecl()) { 270 // We found a similarly-named type or interface; suggest that. 271 if (!SS || !SS->isSet()) 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Lookup.getLookupName() 274 << FixItHint::CreateReplacement(SourceRange(IILoc), 275 Result->getNameAsString()); 276 else if (DeclContext *DC = computeDeclContext(*SS, false)) 277 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 278 << &II << DC << Lookup.getLookupName() << SS->getRange() 279 << FixItHint::CreateReplacement(SourceRange(IILoc), 280 Result->getNameAsString()); 281 else 282 llvm_unreachable("could not have corrected a typo here"); 283 284 Diag(Result->getLocation(), diag::note_previous_decl) 285 << Result->getDeclName(); 286 287 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 288 false, false, ParsedType(), 289 /*NonTrivialTypeSourceInfo=*/true); 290 return true; 291 } 292 } else if (Lookup.empty()) { 293 // We corrected to a keyword. 294 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 295 Diag(IILoc, diag::err_unknown_typename_suggest) 296 << &II << Corrected; 297 return true; 298 } 299 } 300 301 if (getLangOptions().CPlusPlus) { 302 // See if II is a class template that the user forgot to pass arguments to. 303 UnqualifiedId Name; 304 Name.setIdentifier(&II, IILoc); 305 CXXScopeSpec EmptySS; 306 TemplateTy TemplateResult; 307 bool MemberOfUnknownSpecialization; 308 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 309 Name, ParsedType(), true, TemplateResult, 310 MemberOfUnknownSpecialization) == TNK_Type_template) { 311 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 312 Diag(IILoc, diag::err_template_missing_args) << TplName; 313 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 314 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 315 << TplDecl->getTemplateParameters()->getSourceRange(); 316 } 317 return true; 318 } 319 } 320 321 // FIXME: Should we move the logic that tries to recover from a missing tag 322 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 323 324 if (!SS || (!SS->isSet() && !SS->isInvalid())) 325 Diag(IILoc, diag::err_unknown_typename) << &II; 326 else if (DeclContext *DC = computeDeclContext(*SS, false)) 327 Diag(IILoc, diag::err_typename_nested_not_found) 328 << &II << DC << SS->getRange(); 329 else if (isDependentScopeSpecifier(*SS)) { 330 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 331 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 332 << SourceRange(SS->getRange().getBegin(), IILoc) 333 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 334 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 335 } else { 336 assert(SS && SS->isInvalid() && 337 "Invalid scope specifier has already been diagnosed"); 338 } 339 340 return true; 341} 342 343// Determines the context to return to after temporarily entering a 344// context. This depends in an unnecessarily complicated way on the 345// exact ordering of callbacks from the parser. 346DeclContext *Sema::getContainingDC(DeclContext *DC) { 347 348 // Functions defined inline within classes aren't parsed until we've 349 // finished parsing the top-level class, so the top-level class is 350 // the context we'll need to return to. 351 if (isa<FunctionDecl>(DC)) { 352 DC = DC->getLexicalParent(); 353 354 // A function not defined within a class will always return to its 355 // lexical context. 356 if (!isa<CXXRecordDecl>(DC)) 357 return DC; 358 359 // A C++ inline method/friend is parsed *after* the topmost class 360 // it was declared in is fully parsed ("complete"); the topmost 361 // class is the context we need to return to. 362 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 363 DC = RD; 364 365 // Return the declaration context of the topmost class the inline method is 366 // declared in. 367 return DC; 368 } 369 370 // ObjCMethodDecls are parsed (for some reason) outside the context 371 // of the class. 372 if (isa<ObjCMethodDecl>(DC)) 373 return DC->getLexicalParent()->getLexicalParent(); 374 375 return DC->getLexicalParent(); 376} 377 378void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 379 assert(getContainingDC(DC) == CurContext && 380 "The next DeclContext should be lexically contained in the current one."); 381 CurContext = DC; 382 S->setEntity(DC); 383} 384 385void Sema::PopDeclContext() { 386 assert(CurContext && "DeclContext imbalance!"); 387 388 CurContext = getContainingDC(CurContext); 389 assert(CurContext && "Popped translation unit!"); 390} 391 392/// EnterDeclaratorContext - Used when we must lookup names in the context 393/// of a declarator's nested name specifier. 394/// 395void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 396 // C++0x [basic.lookup.unqual]p13: 397 // A name used in the definition of a static data member of class 398 // X (after the qualified-id of the static member) is looked up as 399 // if the name was used in a member function of X. 400 // C++0x [basic.lookup.unqual]p14: 401 // If a variable member of a namespace is defined outside of the 402 // scope of its namespace then any name used in the definition of 403 // the variable member (after the declarator-id) is looked up as 404 // if the definition of the variable member occurred in its 405 // namespace. 406 // Both of these imply that we should push a scope whose context 407 // is the semantic context of the declaration. We can't use 408 // PushDeclContext here because that context is not necessarily 409 // lexically contained in the current context. Fortunately, 410 // the containing scope should have the appropriate information. 411 412 assert(!S->getEntity() && "scope already has entity"); 413 414#ifndef NDEBUG 415 Scope *Ancestor = S->getParent(); 416 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 417 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 418#endif 419 420 CurContext = DC; 421 S->setEntity(DC); 422} 423 424void Sema::ExitDeclaratorContext(Scope *S) { 425 assert(S->getEntity() == CurContext && "Context imbalance!"); 426 427 // Switch back to the lexical context. The safety of this is 428 // enforced by an assert in EnterDeclaratorContext. 429 Scope *Ancestor = S->getParent(); 430 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 431 CurContext = (DeclContext*) Ancestor->getEntity(); 432 433 // We don't need to do anything with the scope, which is going to 434 // disappear. 435} 436 437/// \brief Determine whether we allow overloading of the function 438/// PrevDecl with another declaration. 439/// 440/// This routine determines whether overloading is possible, not 441/// whether some new function is actually an overload. It will return 442/// true in C++ (where we can always provide overloads) or, as an 443/// extension, in C when the previous function is already an 444/// overloaded function declaration or has the "overloadable" 445/// attribute. 446static bool AllowOverloadingOfFunction(LookupResult &Previous, 447 ASTContext &Context) { 448 if (Context.getLangOptions().CPlusPlus) 449 return true; 450 451 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 452 return true; 453 454 return (Previous.getResultKind() == LookupResult::Found 455 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 456} 457 458/// Add this decl to the scope shadowed decl chains. 459void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 460 // Move up the scope chain until we find the nearest enclosing 461 // non-transparent context. The declaration will be introduced into this 462 // scope. 463 while (S->getEntity() && 464 ((DeclContext *)S->getEntity())->isTransparentContext()) 465 S = S->getParent(); 466 467 // Add scoped declarations into their context, so that they can be 468 // found later. Declarations without a context won't be inserted 469 // into any context. 470 if (AddToContext) 471 CurContext->addDecl(D); 472 473 // Out-of-line definitions shouldn't be pushed into scope in C++. 474 // Out-of-line variable and function definitions shouldn't even in C. 475 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 476 D->isOutOfLine()) 477 return; 478 479 // Template instantiations should also not be pushed into scope. 480 if (isa<FunctionDecl>(D) && 481 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 482 return; 483 484 // If this replaces anything in the current scope, 485 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 486 IEnd = IdResolver.end(); 487 for (; I != IEnd; ++I) { 488 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 489 S->RemoveDecl(*I); 490 IdResolver.RemoveDecl(*I); 491 492 // Should only need to replace one decl. 493 break; 494 } 495 } 496 497 S->AddDecl(D); 498 499 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { 500 // Implicitly-generated labels may end up getting generated in an order that 501 // isn't strictly lexical, which breaks name lookup. Be careful to insert 502 // the label at the appropriate place in the identifier chain. 503 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { 504 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); 505 if (IDC == CurContext) { 506 if (!S->isDeclScope(*I)) 507 continue; 508 } else if (IDC->Encloses(CurContext)) 509 break; 510 } 511 512 IdResolver.InsertDeclAfter(I, D); 513 } else { 514 IdResolver.AddDecl(D); 515 } 516} 517 518bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, 519 bool ExplicitInstantiationOrSpecialization) { 520 return IdResolver.isDeclInScope(D, Ctx, Context, S, 521 ExplicitInstantiationOrSpecialization); 522} 523 524Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 525 DeclContext *TargetDC = DC->getPrimaryContext(); 526 do { 527 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 528 if (ScopeDC->getPrimaryContext() == TargetDC) 529 return S; 530 } while ((S = S->getParent())); 531 532 return 0; 533} 534 535static bool isOutOfScopePreviousDeclaration(NamedDecl *, 536 DeclContext*, 537 ASTContext&); 538 539/// Filters out lookup results that don't fall within the given scope 540/// as determined by isDeclInScope. 541static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 542 DeclContext *Ctx, Scope *S, 543 bool ConsiderLinkage, 544 bool ExplicitInstantiationOrSpecialization) { 545 LookupResult::Filter F = R.makeFilter(); 546 while (F.hasNext()) { 547 NamedDecl *D = F.next(); 548 549 if (SemaRef.isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) 550 continue; 551 552 if (ConsiderLinkage && 553 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 554 continue; 555 556 F.erase(); 557 } 558 559 F.done(); 560} 561 562static bool isUsingDecl(NamedDecl *D) { 563 return isa<UsingShadowDecl>(D) || 564 isa<UnresolvedUsingTypenameDecl>(D) || 565 isa<UnresolvedUsingValueDecl>(D); 566} 567 568/// Removes using shadow declarations from the lookup results. 569static void RemoveUsingDecls(LookupResult &R) { 570 LookupResult::Filter F = R.makeFilter(); 571 while (F.hasNext()) 572 if (isUsingDecl(F.next())) 573 F.erase(); 574 575 F.done(); 576} 577 578/// \brief Check for this common pattern: 579/// @code 580/// class S { 581/// S(const S&); // DO NOT IMPLEMENT 582/// void operator=(const S&); // DO NOT IMPLEMENT 583/// }; 584/// @endcode 585static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 586 // FIXME: Should check for private access too but access is set after we get 587 // the decl here. 588 if (D->isThisDeclarationADefinition()) 589 return false; 590 591 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 592 return CD->isCopyConstructor(); 593 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 594 return Method->isCopyAssignmentOperator(); 595 return false; 596} 597 598bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 599 assert(D); 600 601 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 602 return false; 603 604 // Ignore class templates. 605 if (D->getDeclContext()->isDependentContext() || 606 D->getLexicalDeclContext()->isDependentContext()) 607 return false; 608 609 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 610 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 611 return false; 612 613 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 614 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 615 return false; 616 } else { 617 // 'static inline' functions are used in headers; don't warn. 618 if (FD->getStorageClass() == SC_Static && 619 FD->isInlineSpecified()) 620 return false; 621 } 622 623 if (FD->isThisDeclarationADefinition() && 624 Context.DeclMustBeEmitted(FD)) 625 return false; 626 627 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 628 if (!VD->isFileVarDecl() || 629 VD->getType().isConstant(Context) || 630 Context.DeclMustBeEmitted(VD)) 631 return false; 632 633 if (VD->isStaticDataMember() && 634 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 635 return false; 636 637 } else { 638 return false; 639 } 640 641 // Only warn for unused decls internal to the translation unit. 642 if (D->getLinkage() == ExternalLinkage) 643 return false; 644 645 return true; 646} 647 648void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 649 if (!D) 650 return; 651 652 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 653 const FunctionDecl *First = FD->getFirstDeclaration(); 654 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 655 return; // First should already be in the vector. 656 } 657 658 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 659 const VarDecl *First = VD->getFirstDeclaration(); 660 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 661 return; // First should already be in the vector. 662 } 663 664 if (ShouldWarnIfUnusedFileScopedDecl(D)) 665 UnusedFileScopedDecls.push_back(D); 666 } 667 668static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 669 if (D->isInvalidDecl()) 670 return false; 671 672 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 673 return false; 674 675 if (isa<LabelDecl>(D)) 676 return true; 677 678 // White-list anything that isn't a local variable. 679 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 680 !D->getDeclContext()->isFunctionOrMethod()) 681 return false; 682 683 // Types of valid local variables should be complete, so this should succeed. 684 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 685 686 // White-list anything with an __attribute__((unused)) type. 687 QualType Ty = VD->getType(); 688 689 // Only look at the outermost level of typedef. 690 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 691 if (TT->getDecl()->hasAttr<UnusedAttr>()) 692 return false; 693 } 694 695 // If we failed to complete the type for some reason, or if the type is 696 // dependent, don't diagnose the variable. 697 if (Ty->isIncompleteType() || Ty->isDependentType()) 698 return false; 699 700 if (const TagType *TT = Ty->getAs<TagType>()) { 701 const TagDecl *Tag = TT->getDecl(); 702 if (Tag->hasAttr<UnusedAttr>()) 703 return false; 704 705 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 706 // FIXME: Checking for the presence of a user-declared constructor 707 // isn't completely accurate; we'd prefer to check that the initializer 708 // has no side effects. 709 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 710 return false; 711 } 712 } 713 714 // TODO: __attribute__((unused)) templates? 715 } 716 717 return true; 718} 719 720/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 721/// unless they are marked attr(unused). 722void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 723 if (!ShouldDiagnoseUnusedDecl(D)) 724 return; 725 726 unsigned DiagID; 727 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 728 DiagID = diag::warn_unused_exception_param; 729 else if (isa<LabelDecl>(D)) 730 DiagID = diag::warn_unused_label; 731 else 732 DiagID = diag::warn_unused_variable; 733 734 Diag(D->getLocation(), DiagID) << D->getDeclName(); 735} 736 737static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 738 // Verify that we have no forward references left. If so, there was a goto 739 // or address of a label taken, but no definition of it. Label fwd 740 // definitions are indicated with a null substmt. 741 if (L->getStmt() == 0) 742 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 743} 744 745void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 746 if (S->decl_empty()) return; 747 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 748 "Scope shouldn't contain decls!"); 749 750 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 751 I != E; ++I) { 752 Decl *TmpD = (*I); 753 assert(TmpD && "This decl didn't get pushed??"); 754 755 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 756 NamedDecl *D = cast<NamedDecl>(TmpD); 757 758 if (!D->getDeclName()) continue; 759 760 // Diagnose unused variables in this scope. 761 if (!S->hasErrorOccurred()) 762 DiagnoseUnusedDecl(D); 763 764 // If this was a forward reference to a label, verify it was defined. 765 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 766 CheckPoppedLabel(LD, *this); 767 768 // Remove this name from our lexical scope. 769 IdResolver.RemoveDecl(D); 770 } 771} 772 773/// \brief Look for an Objective-C class in the translation unit. 774/// 775/// \param Id The name of the Objective-C class we're looking for. If 776/// typo-correction fixes this name, the Id will be updated 777/// to the fixed name. 778/// 779/// \param IdLoc The location of the name in the translation unit. 780/// 781/// \param TypoCorrection If true, this routine will attempt typo correction 782/// if there is no class with the given name. 783/// 784/// \returns The declaration of the named Objective-C class, or NULL if the 785/// class could not be found. 786ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 787 SourceLocation IdLoc, 788 bool TypoCorrection) { 789 // The third "scope" argument is 0 since we aren't enabling lazy built-in 790 // creation from this context. 791 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 792 793 if (!IDecl && TypoCorrection) { 794 // Perform typo correction at the given location, but only if we 795 // find an Objective-C class name. 796 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 797 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 798 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 799 Diag(IdLoc, diag::err_undef_interface_suggest) 800 << Id << IDecl->getDeclName() 801 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 802 Diag(IDecl->getLocation(), diag::note_previous_decl) 803 << IDecl->getDeclName(); 804 805 Id = IDecl->getIdentifier(); 806 } 807 } 808 809 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 810} 811 812/// getNonFieldDeclScope - Retrieves the innermost scope, starting 813/// from S, where a non-field would be declared. This routine copes 814/// with the difference between C and C++ scoping rules in structs and 815/// unions. For example, the following code is well-formed in C but 816/// ill-formed in C++: 817/// @code 818/// struct S6 { 819/// enum { BAR } e; 820/// }; 821/// 822/// void test_S6() { 823/// struct S6 a; 824/// a.e = BAR; 825/// } 826/// @endcode 827/// For the declaration of BAR, this routine will return a different 828/// scope. The scope S will be the scope of the unnamed enumeration 829/// within S6. In C++, this routine will return the scope associated 830/// with S6, because the enumeration's scope is a transparent 831/// context but structures can contain non-field names. In C, this 832/// routine will return the translation unit scope, since the 833/// enumeration's scope is a transparent context and structures cannot 834/// contain non-field names. 835Scope *Sema::getNonFieldDeclScope(Scope *S) { 836 while (((S->getFlags() & Scope::DeclScope) == 0) || 837 (S->getEntity() && 838 ((DeclContext *)S->getEntity())->isTransparentContext()) || 839 (S->isClassScope() && !getLangOptions().CPlusPlus)) 840 S = S->getParent(); 841 return S; 842} 843 844/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 845/// file scope. lazily create a decl for it. ForRedeclaration is true 846/// if we're creating this built-in in anticipation of redeclaring the 847/// built-in. 848NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 849 Scope *S, bool ForRedeclaration, 850 SourceLocation Loc) { 851 Builtin::ID BID = (Builtin::ID)bid; 852 853 ASTContext::GetBuiltinTypeError Error; 854 QualType R = Context.GetBuiltinType(BID, Error); 855 switch (Error) { 856 case ASTContext::GE_None: 857 // Okay 858 break; 859 860 case ASTContext::GE_Missing_stdio: 861 if (ForRedeclaration) 862 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 863 << Context.BuiltinInfo.GetName(BID); 864 return 0; 865 866 case ASTContext::GE_Missing_setjmp: 867 if (ForRedeclaration) 868 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 869 << Context.BuiltinInfo.GetName(BID); 870 return 0; 871 } 872 873 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 874 Diag(Loc, diag::ext_implicit_lib_function_decl) 875 << Context.BuiltinInfo.GetName(BID) 876 << R; 877 if (Context.BuiltinInfo.getHeaderName(BID) && 878 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 879 != Diagnostic::Ignored) 880 Diag(Loc, diag::note_please_include_header) 881 << Context.BuiltinInfo.getHeaderName(BID) 882 << Context.BuiltinInfo.GetName(BID); 883 } 884 885 FunctionDecl *New = FunctionDecl::Create(Context, 886 Context.getTranslationUnitDecl(), 887 Loc, Loc, II, R, /*TInfo=*/0, 888 SC_Extern, 889 SC_None, false, 890 /*hasPrototype=*/true); 891 New->setImplicit(); 892 893 // Create Decl objects for each parameter, adding them to the 894 // FunctionDecl. 895 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 896 llvm::SmallVector<ParmVarDecl*, 16> Params; 897 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 898 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 899 SourceLocation(), 0, 900 FT->getArgType(i), /*TInfo=*/0, 901 SC_None, SC_None, 0)); 902 New->setParams(Params.data(), Params.size()); 903 } 904 905 AddKnownFunctionAttributes(New); 906 907 // TUScope is the translation-unit scope to insert this function into. 908 // FIXME: This is hideous. We need to teach PushOnScopeChains to 909 // relate Scopes to DeclContexts, and probably eliminate CurContext 910 // entirely, but we're not there yet. 911 DeclContext *SavedContext = CurContext; 912 CurContext = Context.getTranslationUnitDecl(); 913 PushOnScopeChains(New, TUScope); 914 CurContext = SavedContext; 915 return New; 916} 917 918/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 919/// same name and scope as a previous declaration 'Old'. Figure out 920/// how to resolve this situation, merging decls or emitting 921/// diagnostics as appropriate. If there was an error, set New to be invalid. 922/// 923void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 924 // If the new decl is known invalid already, don't bother doing any 925 // merging checks. 926 if (New->isInvalidDecl()) return; 927 928 // Allow multiple definitions for ObjC built-in typedefs. 929 // FIXME: Verify the underlying types are equivalent! 930 if (getLangOptions().ObjC1) { 931 const IdentifierInfo *TypeID = New->getIdentifier(); 932 switch (TypeID->getLength()) { 933 default: break; 934 case 2: 935 if (!TypeID->isStr("id")) 936 break; 937 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 938 // Install the built-in type for 'id', ignoring the current definition. 939 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 940 return; 941 case 5: 942 if (!TypeID->isStr("Class")) 943 break; 944 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 945 // Install the built-in type for 'Class', ignoring the current definition. 946 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 947 return; 948 case 3: 949 if (!TypeID->isStr("SEL")) 950 break; 951 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 952 // Install the built-in type for 'SEL', ignoring the current definition. 953 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 954 return; 955 case 8: 956 if (!TypeID->isStr("Protocol")) 957 break; 958 Context.setObjCProtoType(New->getUnderlyingType()); 959 return; 960 } 961 // Fall through - the typedef name was not a builtin type. 962 } 963 964 // Verify the old decl was also a type. 965 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 966 if (!Old) { 967 Diag(New->getLocation(), diag::err_redefinition_different_kind) 968 << New->getDeclName(); 969 970 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 971 if (OldD->getLocation().isValid()) 972 Diag(OldD->getLocation(), diag::note_previous_definition); 973 974 return New->setInvalidDecl(); 975 } 976 977 // If the old declaration is invalid, just give up here. 978 if (Old->isInvalidDecl()) 979 return New->setInvalidDecl(); 980 981 // Determine the "old" type we'll use for checking and diagnostics. 982 QualType OldType; 983 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 984 OldType = OldTypedef->getUnderlyingType(); 985 else 986 OldType = Context.getTypeDeclType(Old); 987 988 // If the typedef types are not identical, reject them in all languages and 989 // with any extensions enabled. 990 991 if (OldType != New->getUnderlyingType() && 992 Context.getCanonicalType(OldType) != 993 Context.getCanonicalType(New->getUnderlyingType())) { 994 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 995 << New->getUnderlyingType() << OldType; 996 if (Old->getLocation().isValid()) 997 Diag(Old->getLocation(), diag::note_previous_definition); 998 return New->setInvalidDecl(); 999 } 1000 1001 // The types match. Link up the redeclaration chain if the old 1002 // declaration was a typedef. 1003 // FIXME: this is a potential source of wierdness if the type 1004 // spellings don't match exactly. 1005 if (isa<TypedefDecl>(Old)) 1006 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 1007 1008 if (getLangOptions().Microsoft) 1009 return; 1010 1011 if (getLangOptions().CPlusPlus) { 1012 // C++ [dcl.typedef]p2: 1013 // In a given non-class scope, a typedef specifier can be used to 1014 // redefine the name of any type declared in that scope to refer 1015 // to the type to which it already refers. 1016 if (!isa<CXXRecordDecl>(CurContext)) 1017 return; 1018 1019 // C++0x [dcl.typedef]p4: 1020 // In a given class scope, a typedef specifier can be used to redefine 1021 // any class-name declared in that scope that is not also a typedef-name 1022 // to refer to the type to which it already refers. 1023 // 1024 // This wording came in via DR424, which was a correction to the 1025 // wording in DR56, which accidentally banned code like: 1026 // 1027 // struct S { 1028 // typedef struct A { } A; 1029 // }; 1030 // 1031 // in the C++03 standard. We implement the C++0x semantics, which 1032 // allow the above but disallow 1033 // 1034 // struct S { 1035 // typedef int I; 1036 // typedef int I; 1037 // }; 1038 // 1039 // since that was the intent of DR56. 1040 if (!isa<TypedefDecl >(Old)) 1041 return; 1042 1043 Diag(New->getLocation(), diag::err_redefinition) 1044 << New->getDeclName(); 1045 Diag(Old->getLocation(), diag::note_previous_definition); 1046 return New->setInvalidDecl(); 1047 } 1048 1049 // If we have a redefinition of a typedef in C, emit a warning. This warning 1050 // is normally mapped to an error, but can be controlled with 1051 // -Wtypedef-redefinition. If either the original or the redefinition is 1052 // in a system header, don't emit this for compatibility with GCC. 1053 if (getDiagnostics().getSuppressSystemWarnings() && 1054 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1055 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1056 return; 1057 1058 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1059 << New->getDeclName(); 1060 Diag(Old->getLocation(), diag::note_previous_definition); 1061 return; 1062} 1063 1064/// DeclhasAttr - returns true if decl Declaration already has the target 1065/// attribute. 1066static bool 1067DeclHasAttr(const Decl *D, const Attr *A) { 1068 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1069 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1070 if ((*i)->getKind() == A->getKind()) { 1071 // FIXME: Don't hardcode this check 1072 if (OA && isa<OwnershipAttr>(*i)) 1073 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1074 return true; 1075 } 1076 1077 return false; 1078} 1079 1080/// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 1081static void mergeDeclAttributes(Decl *newDecl, const Decl *oldDecl, 1082 ASTContext &C) { 1083 if (!oldDecl->hasAttrs()) 1084 return; 1085 1086 bool foundAny = newDecl->hasAttrs(); 1087 1088 // Ensure that any moving of objects within the allocated map is done before 1089 // we process them. 1090 if (!foundAny) newDecl->setAttrs(AttrVec()); 1091 1092 for (specific_attr_iterator<InheritableAttr> 1093 i = oldDecl->specific_attr_begin<InheritableAttr>(), 1094 e = oldDecl->specific_attr_end<InheritableAttr>(); i != e; ++i) { 1095 if (!DeclHasAttr(newDecl, *i)) { 1096 InheritableAttr *newAttr = cast<InheritableAttr>((*i)->clone(C)); 1097 newAttr->setInherited(true); 1098 newDecl->addAttr(newAttr); 1099 foundAny = true; 1100 } 1101 } 1102 1103 if (!foundAny) newDecl->dropAttrs(); 1104} 1105 1106/// mergeParamDeclAttributes - Copy attributes from the old parameter 1107/// to the new one. 1108static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 1109 const ParmVarDecl *oldDecl, 1110 ASTContext &C) { 1111 if (!oldDecl->hasAttrs()) 1112 return; 1113 1114 bool foundAny = newDecl->hasAttrs(); 1115 1116 // Ensure that any moving of objects within the allocated map is 1117 // done before we process them. 1118 if (!foundAny) newDecl->setAttrs(AttrVec()); 1119 1120 for (specific_attr_iterator<InheritableParamAttr> 1121 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 1122 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 1123 if (!DeclHasAttr(newDecl, *i)) { 1124 InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(C)); 1125 newAttr->setInherited(true); 1126 newDecl->addAttr(newAttr); 1127 foundAny = true; 1128 } 1129 } 1130 1131 if (!foundAny) newDecl->dropAttrs(); 1132} 1133 1134namespace { 1135 1136/// Used in MergeFunctionDecl to keep track of function parameters in 1137/// C. 1138struct GNUCompatibleParamWarning { 1139 ParmVarDecl *OldParm; 1140 ParmVarDecl *NewParm; 1141 QualType PromotedType; 1142}; 1143 1144} 1145 1146/// getSpecialMember - get the special member enum for a method. 1147Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1148 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1149 if (Ctor->isCopyConstructor()) 1150 return Sema::CXXCopyConstructor; 1151 1152 return Sema::CXXConstructor; 1153 } 1154 1155 if (isa<CXXDestructorDecl>(MD)) 1156 return Sema::CXXDestructor; 1157 1158 assert(MD->isCopyAssignmentOperator() && 1159 "Must have copy assignment operator"); 1160 return Sema::CXXCopyAssignment; 1161} 1162 1163/// canRedefineFunction - checks if a function can be redefined. Currently, 1164/// only extern inline functions can be redefined, and even then only in 1165/// GNU89 mode. 1166static bool canRedefineFunction(const FunctionDecl *FD, 1167 const LangOptions& LangOpts) { 1168 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1169 FD->isInlineSpecified() && 1170 FD->getStorageClass() == SC_Extern); 1171} 1172 1173/// MergeFunctionDecl - We just parsed a function 'New' from 1174/// declarator D which has the same name and scope as a previous 1175/// declaration 'Old'. Figure out how to resolve this situation, 1176/// merging decls or emitting diagnostics as appropriate. 1177/// 1178/// In C++, New and Old must be declarations that are not 1179/// overloaded. Use IsOverload to determine whether New and Old are 1180/// overloaded, and to select the Old declaration that New should be 1181/// merged with. 1182/// 1183/// Returns true if there was an error, false otherwise. 1184bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1185 // Verify the old decl was also a function. 1186 FunctionDecl *Old = 0; 1187 if (FunctionTemplateDecl *OldFunctionTemplate 1188 = dyn_cast<FunctionTemplateDecl>(OldD)) 1189 Old = OldFunctionTemplate->getTemplatedDecl(); 1190 else 1191 Old = dyn_cast<FunctionDecl>(OldD); 1192 if (!Old) { 1193 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1194 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1195 Diag(Shadow->getTargetDecl()->getLocation(), 1196 diag::note_using_decl_target); 1197 Diag(Shadow->getUsingDecl()->getLocation(), 1198 diag::note_using_decl) << 0; 1199 return true; 1200 } 1201 1202 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1203 << New->getDeclName(); 1204 Diag(OldD->getLocation(), diag::note_previous_definition); 1205 return true; 1206 } 1207 1208 // Determine whether the previous declaration was a definition, 1209 // implicit declaration, or a declaration. 1210 diag::kind PrevDiag; 1211 if (Old->isThisDeclarationADefinition()) 1212 PrevDiag = diag::note_previous_definition; 1213 else if (Old->isImplicit()) 1214 PrevDiag = diag::note_previous_implicit_declaration; 1215 else 1216 PrevDiag = diag::note_previous_declaration; 1217 1218 QualType OldQType = Context.getCanonicalType(Old->getType()); 1219 QualType NewQType = Context.getCanonicalType(New->getType()); 1220 1221 // Don't complain about this if we're in GNU89 mode and the old function 1222 // is an extern inline function. 1223 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1224 New->getStorageClass() == SC_Static && 1225 Old->getStorageClass() != SC_Static && 1226 !canRedefineFunction(Old, getLangOptions())) { 1227 Diag(New->getLocation(), diag::err_static_non_static) 1228 << New; 1229 Diag(Old->getLocation(), PrevDiag); 1230 return true; 1231 } 1232 1233 // If a function is first declared with a calling convention, but is 1234 // later declared or defined without one, the second decl assumes the 1235 // calling convention of the first. 1236 // 1237 // For the new decl, we have to look at the NON-canonical type to tell the 1238 // difference between a function that really doesn't have a calling 1239 // convention and one that is declared cdecl. That's because in 1240 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1241 // because it is the default calling convention. 1242 // 1243 // Note also that we DO NOT return at this point, because we still have 1244 // other tests to run. 1245 const FunctionType *OldType = cast<FunctionType>(OldQType); 1246 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1247 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1248 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1249 bool RequiresAdjustment = false; 1250 if (OldTypeInfo.getCC() != CC_Default && 1251 NewTypeInfo.getCC() == CC_Default) { 1252 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1253 RequiresAdjustment = true; 1254 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1255 NewTypeInfo.getCC())) { 1256 // Calling conventions really aren't compatible, so complain. 1257 Diag(New->getLocation(), diag::err_cconv_change) 1258 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1259 << (OldTypeInfo.getCC() == CC_Default) 1260 << (OldTypeInfo.getCC() == CC_Default ? "" : 1261 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1262 Diag(Old->getLocation(), diag::note_previous_declaration); 1263 return true; 1264 } 1265 1266 // FIXME: diagnose the other way around? 1267 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1268 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1269 RequiresAdjustment = true; 1270 } 1271 1272 // Merge regparm attribute. 1273 if (OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1274 if (NewTypeInfo.getRegParm()) { 1275 Diag(New->getLocation(), diag::err_regparm_mismatch) 1276 << NewType->getRegParmType() 1277 << OldType->getRegParmType(); 1278 Diag(Old->getLocation(), diag::note_previous_declaration); 1279 return true; 1280 } 1281 1282 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1283 RequiresAdjustment = true; 1284 } 1285 1286 if (RequiresAdjustment) { 1287 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1288 New->setType(QualType(NewType, 0)); 1289 NewQType = Context.getCanonicalType(New->getType()); 1290 } 1291 1292 if (getLangOptions().CPlusPlus) { 1293 // (C++98 13.1p2): 1294 // Certain function declarations cannot be overloaded: 1295 // -- Function declarations that differ only in the return type 1296 // cannot be overloaded. 1297 QualType OldReturnType = OldType->getResultType(); 1298 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1299 QualType ResQT; 1300 if (OldReturnType != NewReturnType) { 1301 if (NewReturnType->isObjCObjectPointerType() 1302 && OldReturnType->isObjCObjectPointerType()) 1303 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1304 if (ResQT.isNull()) { 1305 if (New->isCXXClassMember() && New->isOutOfLine()) 1306 Diag(New->getLocation(), 1307 diag::err_member_def_does_not_match_ret_type) << New; 1308 else 1309 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1310 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1311 return true; 1312 } 1313 else 1314 NewQType = ResQT; 1315 } 1316 1317 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1318 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1319 if (OldMethod && NewMethod) { 1320 // Preserve triviality. 1321 NewMethod->setTrivial(OldMethod->isTrivial()); 1322 1323 bool isFriend = NewMethod->getFriendObjectKind(); 1324 1325 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1326 // -- Member function declarations with the same name and the 1327 // same parameter types cannot be overloaded if any of them 1328 // is a static member function declaration. 1329 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1330 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1331 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1332 return true; 1333 } 1334 1335 // C++ [class.mem]p1: 1336 // [...] A member shall not be declared twice in the 1337 // member-specification, except that a nested class or member 1338 // class template can be declared and then later defined. 1339 unsigned NewDiag; 1340 if (isa<CXXConstructorDecl>(OldMethod)) 1341 NewDiag = diag::err_constructor_redeclared; 1342 else if (isa<CXXDestructorDecl>(NewMethod)) 1343 NewDiag = diag::err_destructor_redeclared; 1344 else if (isa<CXXConversionDecl>(NewMethod)) 1345 NewDiag = diag::err_conv_function_redeclared; 1346 else 1347 NewDiag = diag::err_member_redeclared; 1348 1349 Diag(New->getLocation(), NewDiag); 1350 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1351 1352 // Complain if this is an explicit declaration of a special 1353 // member that was initially declared implicitly. 1354 // 1355 // As an exception, it's okay to befriend such methods in order 1356 // to permit the implicit constructor/destructor/operator calls. 1357 } else if (OldMethod->isImplicit()) { 1358 if (isFriend) { 1359 NewMethod->setImplicit(); 1360 } else { 1361 Diag(NewMethod->getLocation(), 1362 diag::err_definition_of_implicitly_declared_member) 1363 << New << getSpecialMember(OldMethod); 1364 return true; 1365 } 1366 } 1367 } 1368 1369 // (C++98 8.3.5p3): 1370 // All declarations for a function shall agree exactly in both the 1371 // return type and the parameter-type-list. 1372 // We also want to respect all the extended bits except noreturn. 1373 1374 // noreturn should now match unless the old type info didn't have it. 1375 QualType OldQTypeForComparison = OldQType; 1376 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1377 assert(OldQType == QualType(OldType, 0)); 1378 const FunctionType *OldTypeForComparison 1379 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1380 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1381 assert(OldQTypeForComparison.isCanonical()); 1382 } 1383 1384 if (OldQTypeForComparison == NewQType) 1385 return MergeCompatibleFunctionDecls(New, Old); 1386 1387 // Fall through for conflicting redeclarations and redefinitions. 1388 } 1389 1390 // C: Function types need to be compatible, not identical. This handles 1391 // duplicate function decls like "void f(int); void f(enum X);" properly. 1392 if (!getLangOptions().CPlusPlus && 1393 Context.typesAreCompatible(OldQType, NewQType)) { 1394 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1395 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1396 const FunctionProtoType *OldProto = 0; 1397 if (isa<FunctionNoProtoType>(NewFuncType) && 1398 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1399 // The old declaration provided a function prototype, but the 1400 // new declaration does not. Merge in the prototype. 1401 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1402 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1403 OldProto->arg_type_end()); 1404 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1405 ParamTypes.data(), ParamTypes.size(), 1406 OldProto->getExtProtoInfo()); 1407 New->setType(NewQType); 1408 New->setHasInheritedPrototype(); 1409 1410 // Synthesize a parameter for each argument type. 1411 llvm::SmallVector<ParmVarDecl*, 16> Params; 1412 for (FunctionProtoType::arg_type_iterator 1413 ParamType = OldProto->arg_type_begin(), 1414 ParamEnd = OldProto->arg_type_end(); 1415 ParamType != ParamEnd; ++ParamType) { 1416 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1417 SourceLocation(), 1418 SourceLocation(), 0, 1419 *ParamType, /*TInfo=*/0, 1420 SC_None, SC_None, 1421 0); 1422 Param->setImplicit(); 1423 Params.push_back(Param); 1424 } 1425 1426 New->setParams(Params.data(), Params.size()); 1427 } 1428 1429 return MergeCompatibleFunctionDecls(New, Old); 1430 } 1431 1432 // GNU C permits a K&R definition to follow a prototype declaration 1433 // if the declared types of the parameters in the K&R definition 1434 // match the types in the prototype declaration, even when the 1435 // promoted types of the parameters from the K&R definition differ 1436 // from the types in the prototype. GCC then keeps the types from 1437 // the prototype. 1438 // 1439 // If a variadic prototype is followed by a non-variadic K&R definition, 1440 // the K&R definition becomes variadic. This is sort of an edge case, but 1441 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1442 // C99 6.9.1p8. 1443 if (!getLangOptions().CPlusPlus && 1444 Old->hasPrototype() && !New->hasPrototype() && 1445 New->getType()->getAs<FunctionProtoType>() && 1446 Old->getNumParams() == New->getNumParams()) { 1447 llvm::SmallVector<QualType, 16> ArgTypes; 1448 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1449 const FunctionProtoType *OldProto 1450 = Old->getType()->getAs<FunctionProtoType>(); 1451 const FunctionProtoType *NewProto 1452 = New->getType()->getAs<FunctionProtoType>(); 1453 1454 // Determine whether this is the GNU C extension. 1455 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1456 NewProto->getResultType()); 1457 bool LooseCompatible = !MergedReturn.isNull(); 1458 for (unsigned Idx = 0, End = Old->getNumParams(); 1459 LooseCompatible && Idx != End; ++Idx) { 1460 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1461 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1462 if (Context.typesAreCompatible(OldParm->getType(), 1463 NewProto->getArgType(Idx))) { 1464 ArgTypes.push_back(NewParm->getType()); 1465 } else if (Context.typesAreCompatible(OldParm->getType(), 1466 NewParm->getType(), 1467 /*CompareUnqualified=*/true)) { 1468 GNUCompatibleParamWarning Warn 1469 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1470 Warnings.push_back(Warn); 1471 ArgTypes.push_back(NewParm->getType()); 1472 } else 1473 LooseCompatible = false; 1474 } 1475 1476 if (LooseCompatible) { 1477 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1478 Diag(Warnings[Warn].NewParm->getLocation(), 1479 diag::ext_param_promoted_not_compatible_with_prototype) 1480 << Warnings[Warn].PromotedType 1481 << Warnings[Warn].OldParm->getType(); 1482 if (Warnings[Warn].OldParm->getLocation().isValid()) 1483 Diag(Warnings[Warn].OldParm->getLocation(), 1484 diag::note_previous_declaration); 1485 } 1486 1487 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1488 ArgTypes.size(), 1489 OldProto->getExtProtoInfo())); 1490 return MergeCompatibleFunctionDecls(New, Old); 1491 } 1492 1493 // Fall through to diagnose conflicting types. 1494 } 1495 1496 // A function that has already been declared has been redeclared or defined 1497 // with a different type- show appropriate diagnostic 1498 if (unsigned BuiltinID = Old->getBuiltinID()) { 1499 // The user has declared a builtin function with an incompatible 1500 // signature. 1501 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1502 // The function the user is redeclaring is a library-defined 1503 // function like 'malloc' or 'printf'. Warn about the 1504 // redeclaration, then pretend that we don't know about this 1505 // library built-in. 1506 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1507 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1508 << Old << Old->getType(); 1509 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1510 Old->setInvalidDecl(); 1511 return false; 1512 } 1513 1514 PrevDiag = diag::note_previous_builtin_declaration; 1515 } 1516 1517 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1518 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1519 return true; 1520} 1521 1522/// \brief Completes the merge of two function declarations that are 1523/// known to be compatible. 1524/// 1525/// This routine handles the merging of attributes and other 1526/// properties of function declarations form the old declaration to 1527/// the new declaration, once we know that New is in fact a 1528/// redeclaration of Old. 1529/// 1530/// \returns false 1531bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1532 // Merge the attributes 1533 mergeDeclAttributes(New, Old, Context); 1534 1535 // Merge the storage class. 1536 if (Old->getStorageClass() != SC_Extern && 1537 Old->getStorageClass() != SC_None) 1538 New->setStorageClass(Old->getStorageClass()); 1539 1540 // Merge "pure" flag. 1541 if (Old->isPure()) 1542 New->setPure(); 1543 1544 // Merge the "deleted" flag. 1545 if (Old->isDeleted()) 1546 New->setDeleted(); 1547 1548 // Merge attributes from the parameters. These can mismatch with K&R 1549 // declarations. 1550 if (New->getNumParams() == Old->getNumParams()) 1551 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1552 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1553 Context); 1554 1555 if (getLangOptions().CPlusPlus) 1556 return MergeCXXFunctionDecl(New, Old); 1557 1558 return false; 1559} 1560 1561void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1562 const ObjCMethodDecl *oldMethod) { 1563 // Merge the attributes. 1564 mergeDeclAttributes(newMethod, oldMethod, Context); 1565 1566 // Merge attributes from the parameters. 1567 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1568 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1569 ni != ne; ++ni, ++oi) 1570 mergeParamDeclAttributes(*ni, *oi, Context); 1571} 1572 1573/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 1574/// scope as a previous declaration 'Old'. Figure out how to merge their types, 1575/// emitting diagnostics as appropriate. 1576/// 1577/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1578/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1579/// check them before the initializer is attached. 1580/// 1581void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1582 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1583 return; 1584 1585 QualType MergedT; 1586 if (getLangOptions().CPlusPlus) { 1587 AutoType *AT = New->getType()->getContainedAutoType(); 1588 if (AT && !AT->isDeduced()) { 1589 // We don't know what the new type is until the initializer is attached. 1590 return; 1591 } else if (Context.hasSameType(New->getType(), Old->getType())) { 1592 // These could still be something that needs exception specs checked. 1593 return MergeVarDeclExceptionSpecs(New, Old); 1594 } 1595 // C++ [basic.link]p10: 1596 // [...] the types specified by all declarations referring to a given 1597 // object or function shall be identical, except that declarations for an 1598 // array object can specify array types that differ by the presence or 1599 // absence of a major array bound (8.3.4). 1600 else if (Old->getType()->isIncompleteArrayType() && 1601 New->getType()->isArrayType()) { 1602 CanQual<ArrayType> OldArray 1603 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1604 CanQual<ArrayType> NewArray 1605 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1606 if (OldArray->getElementType() == NewArray->getElementType()) 1607 MergedT = New->getType(); 1608 } else if (Old->getType()->isArrayType() && 1609 New->getType()->isIncompleteArrayType()) { 1610 CanQual<ArrayType> OldArray 1611 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1612 CanQual<ArrayType> NewArray 1613 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1614 if (OldArray->getElementType() == NewArray->getElementType()) 1615 MergedT = Old->getType(); 1616 } else if (New->getType()->isObjCObjectPointerType() 1617 && Old->getType()->isObjCObjectPointerType()) { 1618 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1619 Old->getType()); 1620 } 1621 } else { 1622 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1623 } 1624 if (MergedT.isNull()) { 1625 Diag(New->getLocation(), diag::err_redefinition_different_type) 1626 << New->getDeclName(); 1627 Diag(Old->getLocation(), diag::note_previous_definition); 1628 return New->setInvalidDecl(); 1629 } 1630 New->setType(MergedT); 1631} 1632 1633/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1634/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1635/// situation, merging decls or emitting diagnostics as appropriate. 1636/// 1637/// Tentative definition rules (C99 6.9.2p2) are checked by 1638/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1639/// definitions here, since the initializer hasn't been attached. 1640/// 1641void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1642 // If the new decl is already invalid, don't do any other checking. 1643 if (New->isInvalidDecl()) 1644 return; 1645 1646 // Verify the old decl was also a variable. 1647 VarDecl *Old = 0; 1648 if (!Previous.isSingleResult() || 1649 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1650 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1651 << New->getDeclName(); 1652 Diag(Previous.getRepresentativeDecl()->getLocation(), 1653 diag::note_previous_definition); 1654 return New->setInvalidDecl(); 1655 } 1656 1657 // C++ [class.mem]p1: 1658 // A member shall not be declared twice in the member-specification [...] 1659 // 1660 // Here, we need only consider static data members. 1661 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1662 Diag(New->getLocation(), diag::err_duplicate_member) 1663 << New->getIdentifier(); 1664 Diag(Old->getLocation(), diag::note_previous_declaration); 1665 New->setInvalidDecl(); 1666 } 1667 1668 mergeDeclAttributes(New, Old, Context); 1669 1670 // Merge the types. 1671 MergeVarDeclTypes(New, Old); 1672 if (New->isInvalidDecl()) 1673 return; 1674 1675 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1676 if (New->getStorageClass() == SC_Static && 1677 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1678 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1679 Diag(Old->getLocation(), diag::note_previous_definition); 1680 return New->setInvalidDecl(); 1681 } 1682 // C99 6.2.2p4: 1683 // For an identifier declared with the storage-class specifier 1684 // extern in a scope in which a prior declaration of that 1685 // identifier is visible,23) if the prior declaration specifies 1686 // internal or external linkage, the linkage of the identifier at 1687 // the later declaration is the same as the linkage specified at 1688 // the prior declaration. If no prior declaration is visible, or 1689 // if the prior declaration specifies no linkage, then the 1690 // identifier has external linkage. 1691 if (New->hasExternalStorage() && Old->hasLinkage()) 1692 /* Okay */; 1693 else if (New->getStorageClass() != SC_Static && 1694 Old->getStorageClass() == SC_Static) { 1695 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1696 Diag(Old->getLocation(), diag::note_previous_definition); 1697 return New->setInvalidDecl(); 1698 } 1699 1700 // Check if extern is followed by non-extern and vice-versa. 1701 if (New->hasExternalStorage() && 1702 !Old->hasLinkage() && Old->isLocalVarDecl()) { 1703 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 1704 Diag(Old->getLocation(), diag::note_previous_definition); 1705 return New->setInvalidDecl(); 1706 } 1707 if (Old->hasExternalStorage() && 1708 !New->hasLinkage() && New->isLocalVarDecl()) { 1709 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 1710 Diag(Old->getLocation(), diag::note_previous_definition); 1711 return New->setInvalidDecl(); 1712 } 1713 1714 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1715 1716 // FIXME: The test for external storage here seems wrong? We still 1717 // need to check for mismatches. 1718 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1719 // Don't complain about out-of-line definitions of static members. 1720 !(Old->getLexicalDeclContext()->isRecord() && 1721 !New->getLexicalDeclContext()->isRecord())) { 1722 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1723 Diag(Old->getLocation(), diag::note_previous_definition); 1724 return New->setInvalidDecl(); 1725 } 1726 1727 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1728 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1729 Diag(Old->getLocation(), diag::note_previous_definition); 1730 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1731 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1732 Diag(Old->getLocation(), diag::note_previous_definition); 1733 } 1734 1735 // C++ doesn't have tentative definitions, so go right ahead and check here. 1736 const VarDecl *Def; 1737 if (getLangOptions().CPlusPlus && 1738 New->isThisDeclarationADefinition() == VarDecl::Definition && 1739 (Def = Old->getDefinition())) { 1740 Diag(New->getLocation(), diag::err_redefinition) 1741 << New->getDeclName(); 1742 Diag(Def->getLocation(), diag::note_previous_definition); 1743 New->setInvalidDecl(); 1744 return; 1745 } 1746 // c99 6.2.2 P4. 1747 // For an identifier declared with the storage-class specifier extern in a 1748 // scope in which a prior declaration of that identifier is visible, if 1749 // the prior declaration specifies internal or external linkage, the linkage 1750 // of the identifier at the later declaration is the same as the linkage 1751 // specified at the prior declaration. 1752 // FIXME. revisit this code. 1753 if (New->hasExternalStorage() && 1754 Old->getLinkage() == InternalLinkage && 1755 New->getDeclContext() == Old->getDeclContext()) 1756 New->setStorageClass(Old->getStorageClass()); 1757 1758 // Keep a chain of previous declarations. 1759 New->setPreviousDeclaration(Old); 1760 1761 // Inherit access appropriately. 1762 New->setAccess(Old->getAccess()); 1763} 1764 1765/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1766/// no declarator (e.g. "struct foo;") is parsed. 1767Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1768 DeclSpec &DS) { 1769 Decl *TagD = 0; 1770 TagDecl *Tag = 0; 1771 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1772 DS.getTypeSpecType() == DeclSpec::TST_struct || 1773 DS.getTypeSpecType() == DeclSpec::TST_union || 1774 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1775 TagD = DS.getRepAsDecl(); 1776 1777 if (!TagD) // We probably had an error 1778 return 0; 1779 1780 // Note that the above type specs guarantee that the 1781 // type rep is a Decl, whereas in many of the others 1782 // it's a Type. 1783 Tag = dyn_cast<TagDecl>(TagD); 1784 } 1785 1786 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1787 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1788 // or incomplete types shall not be restrict-qualified." 1789 if (TypeQuals & DeclSpec::TQ_restrict) 1790 Diag(DS.getRestrictSpecLoc(), 1791 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1792 << DS.getSourceRange(); 1793 } 1794 1795 if (DS.isFriendSpecified()) { 1796 // If we're dealing with a decl but not a TagDecl, assume that 1797 // whatever routines created it handled the friendship aspect. 1798 if (TagD && !Tag) 1799 return 0; 1800 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1801 } 1802 1803 // Track whether we warned about the fact that there aren't any 1804 // declarators. 1805 bool emittedWarning = false; 1806 1807 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1808 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 1809 1810 if (!Record->getDeclName() && Record->isDefinition() && 1811 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1812 if (getLangOptions().CPlusPlus || 1813 Record->getDeclContext()->isRecord()) 1814 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1815 1816 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1817 << DS.getSourceRange(); 1818 emittedWarning = true; 1819 } 1820 } 1821 1822 // Check for Microsoft C extension: anonymous struct. 1823 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 1824 CurContext->isRecord() && 1825 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 1826 // Handle 2 kinds of anonymous struct: 1827 // struct STRUCT; 1828 // and 1829 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 1830 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 1831 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 1832 (DS.getTypeSpecType() == DeclSpec::TST_typename && 1833 DS.getRepAsType().get()->isStructureType())) { 1834 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 1835 << DS.getSourceRange(); 1836 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 1837 } 1838 } 1839 1840 if (getLangOptions().CPlusPlus && 1841 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1842 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1843 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1844 !Enum->getIdentifier() && !Enum->isInvalidDecl()) { 1845 Diag(Enum->getLocation(), diag::ext_no_declarators) 1846 << DS.getSourceRange(); 1847 emittedWarning = true; 1848 } 1849 1850 // Skip all the checks below if we have a type error. 1851 if (DS.getTypeSpecType() == DeclSpec::TST_error) return TagD; 1852 1853 if (!DS.isMissingDeclaratorOk()) { 1854 // Warn about typedefs of enums without names, since this is an 1855 // extension in both Microsoft and GNU. 1856 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1857 Tag && isa<EnumDecl>(Tag)) { 1858 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1859 << DS.getSourceRange(); 1860 return Tag; 1861 } 1862 1863 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1864 << DS.getSourceRange(); 1865 emittedWarning = true; 1866 } 1867 1868 // We're going to complain about a bunch of spurious specifiers; 1869 // only do this if we're declaring a tag, because otherwise we 1870 // should be getting diag::ext_no_declarators. 1871 if (emittedWarning || (TagD && TagD->isInvalidDecl())) 1872 return TagD; 1873 1874 // Note that a linkage-specification sets a storage class, but 1875 // 'extern "C" struct foo;' is actually valid and not theoretically 1876 // useless. 1877 if (DeclSpec::SCS scs = DS.getStorageClassSpec()) 1878 if (!DS.isExternInLinkageSpec()) 1879 Diag(DS.getStorageClassSpecLoc(), diag::warn_standalone_specifier) 1880 << DeclSpec::getSpecifierName(scs); 1881 1882 if (DS.isThreadSpecified()) 1883 Diag(DS.getThreadSpecLoc(), diag::warn_standalone_specifier) << "__thread"; 1884 if (DS.getTypeQualifiers()) { 1885 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 1886 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "const"; 1887 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 1888 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "volatile"; 1889 // Restrict is covered above. 1890 } 1891 if (DS.isInlineSpecified()) 1892 Diag(DS.getInlineSpecLoc(), diag::warn_standalone_specifier) << "inline"; 1893 if (DS.isVirtualSpecified()) 1894 Diag(DS.getVirtualSpecLoc(), diag::warn_standalone_specifier) << "virtual"; 1895 if (DS.isExplicitSpecified()) 1896 Diag(DS.getExplicitSpecLoc(), diag::warn_standalone_specifier) <<"explicit"; 1897 1898 // FIXME: Warn on useless attributes 1899 1900 return TagD; 1901} 1902 1903/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1904/// builds a statement for it and returns it so it is evaluated. 1905StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1906 StmtResult R; 1907 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1908 Expr *Exp = DS.getRepAsExpr(); 1909 QualType Ty = Exp->getType(); 1910 if (Ty->isPointerType()) { 1911 do 1912 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1913 while (Ty->isPointerType()); 1914 } 1915 if (Ty->isVariableArrayType()) { 1916 R = ActOnExprStmt(MakeFullExpr(Exp)); 1917 } 1918 } 1919 return R; 1920} 1921 1922/// We are trying to inject an anonymous member into the given scope; 1923/// check if there's an existing declaration that can't be overloaded. 1924/// 1925/// \return true if this is a forbidden redeclaration 1926static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1927 Scope *S, 1928 DeclContext *Owner, 1929 DeclarationName Name, 1930 SourceLocation NameLoc, 1931 unsigned diagnostic) { 1932 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1933 Sema::ForRedeclaration); 1934 if (!SemaRef.LookupName(R, S)) return false; 1935 1936 if (R.getAsSingle<TagDecl>()) 1937 return false; 1938 1939 // Pick a representative declaration. 1940 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1941 assert(PrevDecl && "Expected a non-null Decl"); 1942 1943 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1944 return false; 1945 1946 SemaRef.Diag(NameLoc, diagnostic) << Name; 1947 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1948 1949 return true; 1950} 1951 1952/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1953/// anonymous struct or union AnonRecord into the owning context Owner 1954/// and scope S. This routine will be invoked just after we realize 1955/// that an unnamed union or struct is actually an anonymous union or 1956/// struct, e.g., 1957/// 1958/// @code 1959/// union { 1960/// int i; 1961/// float f; 1962/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1963/// // f into the surrounding scope.x 1964/// @endcode 1965/// 1966/// This routine is recursive, injecting the names of nested anonymous 1967/// structs/unions into the owning context and scope as well. 1968static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1969 DeclContext *Owner, 1970 RecordDecl *AnonRecord, 1971 AccessSpecifier AS, 1972 llvm::SmallVector<NamedDecl*, 2> &Chaining, 1973 bool MSAnonStruct) { 1974 unsigned diagKind 1975 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1976 : diag::err_anonymous_struct_member_redecl; 1977 1978 bool Invalid = false; 1979 1980 // Look every FieldDecl and IndirectFieldDecl with a name. 1981 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 1982 DEnd = AnonRecord->decls_end(); 1983 D != DEnd; ++D) { 1984 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 1985 cast<NamedDecl>(*D)->getDeclName()) { 1986 ValueDecl *VD = cast<ValueDecl>(*D); 1987 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 1988 VD->getLocation(), diagKind)) { 1989 // C++ [class.union]p2: 1990 // The names of the members of an anonymous union shall be 1991 // distinct from the names of any other entity in the 1992 // scope in which the anonymous union is declared. 1993 Invalid = true; 1994 } else { 1995 // C++ [class.union]p2: 1996 // For the purpose of name lookup, after the anonymous union 1997 // definition, the members of the anonymous union are 1998 // considered to have been defined in the scope in which the 1999 // anonymous union is declared. 2000 unsigned OldChainingSize = Chaining.size(); 2001 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 2002 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 2003 PE = IF->chain_end(); PI != PE; ++PI) 2004 Chaining.push_back(*PI); 2005 else 2006 Chaining.push_back(VD); 2007 2008 assert(Chaining.size() >= 2); 2009 NamedDecl **NamedChain = 2010 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 2011 for (unsigned i = 0; i < Chaining.size(); i++) 2012 NamedChain[i] = Chaining[i]; 2013 2014 IndirectFieldDecl* IndirectField = 2015 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 2016 VD->getIdentifier(), VD->getType(), 2017 NamedChain, Chaining.size()); 2018 2019 IndirectField->setAccess(AS); 2020 IndirectField->setImplicit(); 2021 SemaRef.PushOnScopeChains(IndirectField, S); 2022 2023 // That includes picking up the appropriate access specifier. 2024 if (AS != AS_none) IndirectField->setAccess(AS); 2025 2026 Chaining.resize(OldChainingSize); 2027 } 2028 } 2029 } 2030 2031 return Invalid; 2032} 2033 2034/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 2035/// a VarDecl::StorageClass. Any error reporting is up to the caller: 2036/// illegal input values are mapped to SC_None. 2037static StorageClass 2038StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2039 switch (StorageClassSpec) { 2040 case DeclSpec::SCS_unspecified: return SC_None; 2041 case DeclSpec::SCS_extern: return SC_Extern; 2042 case DeclSpec::SCS_static: return SC_Static; 2043 case DeclSpec::SCS_auto: return SC_Auto; 2044 case DeclSpec::SCS_register: return SC_Register; 2045 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2046 // Illegal SCSs map to None: error reporting is up to the caller. 2047 case DeclSpec::SCS_mutable: // Fall through. 2048 case DeclSpec::SCS_typedef: return SC_None; 2049 } 2050 llvm_unreachable("unknown storage class specifier"); 2051} 2052 2053/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 2054/// a StorageClass. Any error reporting is up to the caller: 2055/// illegal input values are mapped to SC_None. 2056static StorageClass 2057StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2058 switch (StorageClassSpec) { 2059 case DeclSpec::SCS_unspecified: return SC_None; 2060 case DeclSpec::SCS_extern: return SC_Extern; 2061 case DeclSpec::SCS_static: return SC_Static; 2062 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2063 // Illegal SCSs map to None: error reporting is up to the caller. 2064 case DeclSpec::SCS_auto: // Fall through. 2065 case DeclSpec::SCS_mutable: // Fall through. 2066 case DeclSpec::SCS_register: // Fall through. 2067 case DeclSpec::SCS_typedef: return SC_None; 2068 } 2069 llvm_unreachable("unknown storage class specifier"); 2070} 2071 2072/// BuildAnonymousStructOrUnion - Handle the declaration of an 2073/// anonymous structure or union. Anonymous unions are a C++ feature 2074/// (C++ [class.union]) and a GNU C extension; anonymous structures 2075/// are a GNU C and GNU C++ extension. 2076Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2077 AccessSpecifier AS, 2078 RecordDecl *Record) { 2079 DeclContext *Owner = Record->getDeclContext(); 2080 2081 // Diagnose whether this anonymous struct/union is an extension. 2082 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2083 Diag(Record->getLocation(), diag::ext_anonymous_union); 2084 else if (!Record->isUnion()) 2085 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2086 2087 // C and C++ require different kinds of checks for anonymous 2088 // structs/unions. 2089 bool Invalid = false; 2090 if (getLangOptions().CPlusPlus) { 2091 const char* PrevSpec = 0; 2092 unsigned DiagID; 2093 // C++ [class.union]p3: 2094 // Anonymous unions declared in a named namespace or in the 2095 // global namespace shall be declared static. 2096 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2097 (isa<TranslationUnitDecl>(Owner) || 2098 (isa<NamespaceDecl>(Owner) && 2099 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2100 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2101 Invalid = true; 2102 2103 // Recover by adding 'static'. 2104 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2105 PrevSpec, DiagID, getLangOptions()); 2106 } 2107 // C++ [class.union]p3: 2108 // A storage class is not allowed in a declaration of an 2109 // anonymous union in a class scope. 2110 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2111 isa<RecordDecl>(Owner)) { 2112 Diag(DS.getStorageClassSpecLoc(), 2113 diag::err_anonymous_union_with_storage_spec); 2114 Invalid = true; 2115 2116 // Recover by removing the storage specifier. 2117 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2118 PrevSpec, DiagID, getLangOptions()); 2119 } 2120 2121 // C++ [class.union]p2: 2122 // The member-specification of an anonymous union shall only 2123 // define non-static data members. [Note: nested types and 2124 // functions cannot be declared within an anonymous union. ] 2125 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2126 MemEnd = Record->decls_end(); 2127 Mem != MemEnd; ++Mem) { 2128 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2129 // C++ [class.union]p3: 2130 // An anonymous union shall not have private or protected 2131 // members (clause 11). 2132 assert(FD->getAccess() != AS_none); 2133 if (FD->getAccess() != AS_public) { 2134 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2135 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2136 Invalid = true; 2137 } 2138 2139 if (CheckNontrivialField(FD)) 2140 Invalid = true; 2141 } else if ((*Mem)->isImplicit()) { 2142 // Any implicit members are fine. 2143 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2144 // This is a type that showed up in an 2145 // elaborated-type-specifier inside the anonymous struct or 2146 // union, but which actually declares a type outside of the 2147 // anonymous struct or union. It's okay. 2148 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2149 if (!MemRecord->isAnonymousStructOrUnion() && 2150 MemRecord->getDeclName()) { 2151 // Visual C++ allows type definition in anonymous struct or union. 2152 if (getLangOptions().Microsoft) 2153 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2154 << (int)Record->isUnion(); 2155 else { 2156 // This is a nested type declaration. 2157 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2158 << (int)Record->isUnion(); 2159 Invalid = true; 2160 } 2161 } 2162 } else if (isa<AccessSpecDecl>(*Mem)) { 2163 // Any access specifier is fine. 2164 } else { 2165 // We have something that isn't a non-static data 2166 // member. Complain about it. 2167 unsigned DK = diag::err_anonymous_record_bad_member; 2168 if (isa<TypeDecl>(*Mem)) 2169 DK = diag::err_anonymous_record_with_type; 2170 else if (isa<FunctionDecl>(*Mem)) 2171 DK = diag::err_anonymous_record_with_function; 2172 else if (isa<VarDecl>(*Mem)) 2173 DK = diag::err_anonymous_record_with_static; 2174 2175 // Visual C++ allows type definition in anonymous struct or union. 2176 if (getLangOptions().Microsoft && 2177 DK == diag::err_anonymous_record_with_type) 2178 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2179 << (int)Record->isUnion(); 2180 else { 2181 Diag((*Mem)->getLocation(), DK) 2182 << (int)Record->isUnion(); 2183 Invalid = true; 2184 } 2185 } 2186 } 2187 } 2188 2189 if (!Record->isUnion() && !Owner->isRecord()) { 2190 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2191 << (int)getLangOptions().CPlusPlus; 2192 Invalid = true; 2193 } 2194 2195 // Mock up a declarator. 2196 Declarator Dc(DS, Declarator::TypeNameContext); 2197 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2198 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2199 2200 // Create a declaration for this anonymous struct/union. 2201 NamedDecl *Anon = 0; 2202 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2203 Anon = FieldDecl::Create(Context, OwningClass, 2204 DS.getSourceRange().getBegin(), 2205 Record->getLocation(), 2206 /*IdentifierInfo=*/0, 2207 Context.getTypeDeclType(Record), 2208 TInfo, 2209 /*BitWidth=*/0, /*Mutable=*/false); 2210 Anon->setAccess(AS); 2211 if (getLangOptions().CPlusPlus) 2212 FieldCollector->Add(cast<FieldDecl>(Anon)); 2213 } else { 2214 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2215 assert(SCSpec != DeclSpec::SCS_typedef && 2216 "Parser allowed 'typedef' as storage class VarDecl."); 2217 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2218 if (SCSpec == DeclSpec::SCS_mutable) { 2219 // mutable can only appear on non-static class members, so it's always 2220 // an error here 2221 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2222 Invalid = true; 2223 SC = SC_None; 2224 } 2225 SCSpec = DS.getStorageClassSpecAsWritten(); 2226 VarDecl::StorageClass SCAsWritten 2227 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2228 2229 Anon = VarDecl::Create(Context, Owner, 2230 DS.getSourceRange().getBegin(), 2231 Record->getLocation(), /*IdentifierInfo=*/0, 2232 Context.getTypeDeclType(Record), 2233 TInfo, SC, SCAsWritten); 2234 } 2235 Anon->setImplicit(); 2236 2237 // Add the anonymous struct/union object to the current 2238 // context. We'll be referencing this object when we refer to one of 2239 // its members. 2240 Owner->addDecl(Anon); 2241 2242 // Inject the members of the anonymous struct/union into the owning 2243 // context and into the identifier resolver chain for name lookup 2244 // purposes. 2245 llvm::SmallVector<NamedDecl*, 2> Chain; 2246 Chain.push_back(Anon); 2247 2248 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2249 Chain, false)) 2250 Invalid = true; 2251 2252 // Mark this as an anonymous struct/union type. Note that we do not 2253 // do this until after we have already checked and injected the 2254 // members of this anonymous struct/union type, because otherwise 2255 // the members could be injected twice: once by DeclContext when it 2256 // builds its lookup table, and once by 2257 // InjectAnonymousStructOrUnionMembers. 2258 Record->setAnonymousStructOrUnion(true); 2259 2260 if (Invalid) 2261 Anon->setInvalidDecl(); 2262 2263 return Anon; 2264} 2265 2266/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2267/// Microsoft C anonymous structure. 2268/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2269/// Example: 2270/// 2271/// struct A { int a; }; 2272/// struct B { struct A; int b; }; 2273/// 2274/// void foo() { 2275/// B var; 2276/// var.a = 3; 2277/// } 2278/// 2279Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2280 RecordDecl *Record) { 2281 2282 // If there is no Record, get the record via the typedef. 2283 if (!Record) 2284 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2285 2286 // Mock up a declarator. 2287 Declarator Dc(DS, Declarator::TypeNameContext); 2288 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2289 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2290 2291 // Create a declaration for this anonymous struct. 2292 NamedDecl* Anon = FieldDecl::Create(Context, 2293 cast<RecordDecl>(CurContext), 2294 DS.getSourceRange().getBegin(), 2295 DS.getSourceRange().getBegin(), 2296 /*IdentifierInfo=*/0, 2297 Context.getTypeDeclType(Record), 2298 TInfo, 2299 /*BitWidth=*/0, /*Mutable=*/false); 2300 Anon->setImplicit(); 2301 2302 // Add the anonymous struct object to the current context. 2303 CurContext->addDecl(Anon); 2304 2305 // Inject the members of the anonymous struct into the current 2306 // context and into the identifier resolver chain for name lookup 2307 // purposes. 2308 llvm::SmallVector<NamedDecl*, 2> Chain; 2309 Chain.push_back(Anon); 2310 2311 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2312 Record->getDefinition(), 2313 AS_none, Chain, true)) 2314 Anon->setInvalidDecl(); 2315 2316 return Anon; 2317} 2318 2319/// GetNameForDeclarator - Determine the full declaration name for the 2320/// given Declarator. 2321DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2322 return GetNameFromUnqualifiedId(D.getName()); 2323} 2324 2325/// \brief Retrieves the declaration name from a parsed unqualified-id. 2326DeclarationNameInfo 2327Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2328 DeclarationNameInfo NameInfo; 2329 NameInfo.setLoc(Name.StartLocation); 2330 2331 switch (Name.getKind()) { 2332 2333 case UnqualifiedId::IK_Identifier: 2334 NameInfo.setName(Name.Identifier); 2335 NameInfo.setLoc(Name.StartLocation); 2336 return NameInfo; 2337 2338 case UnqualifiedId::IK_OperatorFunctionId: 2339 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2340 Name.OperatorFunctionId.Operator)); 2341 NameInfo.setLoc(Name.StartLocation); 2342 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2343 = Name.OperatorFunctionId.SymbolLocations[0]; 2344 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2345 = Name.EndLocation.getRawEncoding(); 2346 return NameInfo; 2347 2348 case UnqualifiedId::IK_LiteralOperatorId: 2349 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2350 Name.Identifier)); 2351 NameInfo.setLoc(Name.StartLocation); 2352 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2353 return NameInfo; 2354 2355 case UnqualifiedId::IK_ConversionFunctionId: { 2356 TypeSourceInfo *TInfo; 2357 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2358 if (Ty.isNull()) 2359 return DeclarationNameInfo(); 2360 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2361 Context.getCanonicalType(Ty))); 2362 NameInfo.setLoc(Name.StartLocation); 2363 NameInfo.setNamedTypeInfo(TInfo); 2364 return NameInfo; 2365 } 2366 2367 case UnqualifiedId::IK_ConstructorName: { 2368 TypeSourceInfo *TInfo; 2369 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2370 if (Ty.isNull()) 2371 return DeclarationNameInfo(); 2372 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2373 Context.getCanonicalType(Ty))); 2374 NameInfo.setLoc(Name.StartLocation); 2375 NameInfo.setNamedTypeInfo(TInfo); 2376 return NameInfo; 2377 } 2378 2379 case UnqualifiedId::IK_ConstructorTemplateId: { 2380 // In well-formed code, we can only have a constructor 2381 // template-id that refers to the current context, so go there 2382 // to find the actual type being constructed. 2383 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2384 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2385 return DeclarationNameInfo(); 2386 2387 // Determine the type of the class being constructed. 2388 QualType CurClassType = Context.getTypeDeclType(CurClass); 2389 2390 // FIXME: Check two things: that the template-id names the same type as 2391 // CurClassType, and that the template-id does not occur when the name 2392 // was qualified. 2393 2394 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2395 Context.getCanonicalType(CurClassType))); 2396 NameInfo.setLoc(Name.StartLocation); 2397 // FIXME: should we retrieve TypeSourceInfo? 2398 NameInfo.setNamedTypeInfo(0); 2399 return NameInfo; 2400 } 2401 2402 case UnqualifiedId::IK_DestructorName: { 2403 TypeSourceInfo *TInfo; 2404 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2405 if (Ty.isNull()) 2406 return DeclarationNameInfo(); 2407 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2408 Context.getCanonicalType(Ty))); 2409 NameInfo.setLoc(Name.StartLocation); 2410 NameInfo.setNamedTypeInfo(TInfo); 2411 return NameInfo; 2412 } 2413 2414 case UnqualifiedId::IK_TemplateId: { 2415 TemplateName TName = Name.TemplateId->Template.get(); 2416 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2417 return Context.getNameForTemplate(TName, TNameLoc); 2418 } 2419 2420 } // switch (Name.getKind()) 2421 2422 assert(false && "Unknown name kind"); 2423 return DeclarationNameInfo(); 2424} 2425 2426/// isNearlyMatchingFunction - Determine whether the C++ functions 2427/// Declaration and Definition are "nearly" matching. This heuristic 2428/// is used to improve diagnostics in the case where an out-of-line 2429/// function definition doesn't match any declaration within 2430/// the class or namespace. 2431static bool isNearlyMatchingFunction(ASTContext &Context, 2432 FunctionDecl *Declaration, 2433 FunctionDecl *Definition) { 2434 if (Declaration->param_size() != Definition->param_size()) 2435 return false; 2436 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2437 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2438 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2439 2440 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2441 DefParamTy.getNonReferenceType())) 2442 return false; 2443 } 2444 2445 return true; 2446} 2447 2448/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2449/// declarator needs to be rebuilt in the current instantiation. 2450/// Any bits of declarator which appear before the name are valid for 2451/// consideration here. That's specifically the type in the decl spec 2452/// and the base type in any member-pointer chunks. 2453static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2454 DeclarationName Name) { 2455 // The types we specifically need to rebuild are: 2456 // - typenames, typeofs, and decltypes 2457 // - types which will become injected class names 2458 // Of course, we also need to rebuild any type referencing such a 2459 // type. It's safest to just say "dependent", but we call out a 2460 // few cases here. 2461 2462 DeclSpec &DS = D.getMutableDeclSpec(); 2463 switch (DS.getTypeSpecType()) { 2464 case DeclSpec::TST_typename: 2465 case DeclSpec::TST_typeofType: 2466 case DeclSpec::TST_decltype: { 2467 // Grab the type from the parser. 2468 TypeSourceInfo *TSI = 0; 2469 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2470 if (T.isNull() || !T->isDependentType()) break; 2471 2472 // Make sure there's a type source info. This isn't really much 2473 // of a waste; most dependent types should have type source info 2474 // attached already. 2475 if (!TSI) 2476 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2477 2478 // Rebuild the type in the current instantiation. 2479 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2480 if (!TSI) return true; 2481 2482 // Store the new type back in the decl spec. 2483 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2484 DS.UpdateTypeRep(LocType); 2485 break; 2486 } 2487 2488 case DeclSpec::TST_typeofExpr: { 2489 Expr *E = DS.getRepAsExpr(); 2490 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2491 if (Result.isInvalid()) return true; 2492 DS.UpdateExprRep(Result.get()); 2493 break; 2494 } 2495 2496 default: 2497 // Nothing to do for these decl specs. 2498 break; 2499 } 2500 2501 // It doesn't matter what order we do this in. 2502 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2503 DeclaratorChunk &Chunk = D.getTypeObject(I); 2504 2505 // The only type information in the declarator which can come 2506 // before the declaration name is the base type of a member 2507 // pointer. 2508 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2509 continue; 2510 2511 // Rebuild the scope specifier in-place. 2512 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2513 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2514 return true; 2515 } 2516 2517 return false; 2518} 2519 2520Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2521 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2522} 2523 2524Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2525 MultiTemplateParamsArg TemplateParamLists, 2526 bool IsFunctionDefinition) { 2527 // TODO: consider using NameInfo for diagnostic. 2528 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2529 DeclarationName Name = NameInfo.getName(); 2530 2531 // All of these full declarators require an identifier. If it doesn't have 2532 // one, the ParsedFreeStandingDeclSpec action should be used. 2533 if (!Name) { 2534 if (!D.isInvalidType()) // Reject this if we think it is valid. 2535 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2536 diag::err_declarator_need_ident) 2537 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2538 return 0; 2539 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2540 return 0; 2541 2542 // The scope passed in may not be a decl scope. Zip up the scope tree until 2543 // we find one that is. 2544 while ((S->getFlags() & Scope::DeclScope) == 0 || 2545 (S->getFlags() & Scope::TemplateParamScope) != 0) 2546 S = S->getParent(); 2547 2548 DeclContext *DC = CurContext; 2549 if (D.getCXXScopeSpec().isInvalid()) 2550 D.setInvalidType(); 2551 else if (D.getCXXScopeSpec().isSet()) { 2552 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2553 UPPC_DeclarationQualifier)) 2554 return 0; 2555 2556 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2557 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2558 if (!DC) { 2559 // If we could not compute the declaration context, it's because the 2560 // declaration context is dependent but does not refer to a class, 2561 // class template, or class template partial specialization. Complain 2562 // and return early, to avoid the coming semantic disaster. 2563 Diag(D.getIdentifierLoc(), 2564 diag::err_template_qualified_declarator_no_match) 2565 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2566 << D.getCXXScopeSpec().getRange(); 2567 return 0; 2568 } 2569 2570 bool IsDependentContext = DC->isDependentContext(); 2571 2572 if (!IsDependentContext && 2573 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2574 return 0; 2575 2576 if (isa<CXXRecordDecl>(DC)) { 2577 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2578 Diag(D.getIdentifierLoc(), 2579 diag::err_member_def_undefined_record) 2580 << Name << DC << D.getCXXScopeSpec().getRange(); 2581 D.setInvalidType(); 2582 } else if (isa<CXXRecordDecl>(CurContext) && 2583 !D.getDeclSpec().isFriendSpecified()) { 2584 // The user provided a superfluous scope specifier inside a class 2585 // definition: 2586 // 2587 // class X { 2588 // void X::f(); 2589 // }; 2590 if (CurContext->Equals(DC)) 2591 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2592 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2593 else 2594 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2595 << Name << D.getCXXScopeSpec().getRange(); 2596 2597 // Pretend that this qualifier was not here. 2598 D.getCXXScopeSpec().clear(); 2599 } 2600 } 2601 2602 // Check whether we need to rebuild the type of the given 2603 // declaration in the current instantiation. 2604 if (EnteringContext && IsDependentContext && 2605 TemplateParamLists.size() != 0) { 2606 ContextRAII SavedContext(*this, DC); 2607 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2608 D.setInvalidType(); 2609 } 2610 } 2611 2612 // C++ [class.mem]p13: 2613 // If T is the name of a class, then each of the following shall have a 2614 // name different from T: 2615 // - every static data member of class T; 2616 // - every member function of class T 2617 // - every member of class T that is itself a type; 2618 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2619 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2620 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2621 << Name; 2622 2623 // If this is a typedef, we'll end up spewing multiple diagnostics. 2624 // Just return early; it's safer. 2625 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2626 return 0; 2627 } 2628 2629 NamedDecl *New; 2630 2631 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2632 QualType R = TInfo->getType(); 2633 2634 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 2635 UPPC_DeclarationType)) 2636 D.setInvalidType(); 2637 2638 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2639 ForRedeclaration); 2640 2641 // See if this is a redefinition of a variable in the same scope. 2642 if (!D.getCXXScopeSpec().isSet()) { 2643 bool IsLinkageLookup = false; 2644 2645 // If the declaration we're planning to build will be a function 2646 // or object with linkage, then look for another declaration with 2647 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2648 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2649 /* Do nothing*/; 2650 else if (R->isFunctionType()) { 2651 if (CurContext->isFunctionOrMethod() || 2652 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2653 IsLinkageLookup = true; 2654 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2655 IsLinkageLookup = true; 2656 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2657 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2658 IsLinkageLookup = true; 2659 2660 if (IsLinkageLookup) 2661 Previous.clear(LookupRedeclarationWithLinkage); 2662 2663 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2664 } else { // Something like "int foo::x;" 2665 LookupQualifiedName(Previous, DC); 2666 2667 // Don't consider using declarations as previous declarations for 2668 // out-of-line members. 2669 RemoveUsingDecls(Previous); 2670 2671 // C++ 7.3.1.2p2: 2672 // Members (including explicit specializations of templates) of a named 2673 // namespace can also be defined outside that namespace by explicit 2674 // qualification of the name being defined, provided that the entity being 2675 // defined was already declared in the namespace and the definition appears 2676 // after the point of declaration in a namespace that encloses the 2677 // declarations namespace. 2678 // 2679 // Note that we only check the context at this point. We don't yet 2680 // have enough information to make sure that PrevDecl is actually 2681 // the declaration we want to match. For example, given: 2682 // 2683 // class X { 2684 // void f(); 2685 // void f(float); 2686 // }; 2687 // 2688 // void X::f(int) { } // ill-formed 2689 // 2690 // In this case, PrevDecl will point to the overload set 2691 // containing the two f's declared in X, but neither of them 2692 // matches. 2693 2694 // First check whether we named the global scope. 2695 if (isa<TranslationUnitDecl>(DC)) { 2696 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2697 << Name << D.getCXXScopeSpec().getRange(); 2698 } else { 2699 DeclContext *Cur = CurContext; 2700 while (isa<LinkageSpecDecl>(Cur)) 2701 Cur = Cur->getParent(); 2702 if (!Cur->Encloses(DC)) { 2703 // The qualifying scope doesn't enclose the original declaration. 2704 // Emit diagnostic based on current scope. 2705 SourceLocation L = D.getIdentifierLoc(); 2706 SourceRange R = D.getCXXScopeSpec().getRange(); 2707 if (isa<FunctionDecl>(Cur)) 2708 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2709 else 2710 Diag(L, diag::err_invalid_declarator_scope) 2711 << Name << cast<NamedDecl>(DC) << R; 2712 D.setInvalidType(); 2713 } 2714 } 2715 } 2716 2717 if (Previous.isSingleResult() && 2718 Previous.getFoundDecl()->isTemplateParameter()) { 2719 // Maybe we will complain about the shadowed template parameter. 2720 if (!D.isInvalidType()) 2721 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2722 Previous.getFoundDecl())) 2723 D.setInvalidType(); 2724 2725 // Just pretend that we didn't see the previous declaration. 2726 Previous.clear(); 2727 } 2728 2729 // In C++, the previous declaration we find might be a tag type 2730 // (class or enum). In this case, the new declaration will hide the 2731 // tag type. Note that this does does not apply if we're declaring a 2732 // typedef (C++ [dcl.typedef]p4). 2733 if (Previous.isSingleTagDecl() && 2734 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2735 Previous.clear(); 2736 2737 bool Redeclaration = false; 2738 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2739 if (TemplateParamLists.size()) { 2740 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2741 return 0; 2742 } 2743 2744 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2745 } else if (R->isFunctionType()) { 2746 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2747 move(TemplateParamLists), 2748 IsFunctionDefinition, Redeclaration); 2749 } else { 2750 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2751 move(TemplateParamLists), 2752 Redeclaration); 2753 } 2754 2755 if (New == 0) 2756 return 0; 2757 2758 // If this has an identifier and is not an invalid redeclaration or 2759 // function template specialization, add it to the scope stack. 2760 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2761 PushOnScopeChains(New, S); 2762 2763 return New; 2764} 2765 2766/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2767/// types into constant array types in certain situations which would otherwise 2768/// be errors (for GCC compatibility). 2769static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2770 ASTContext &Context, 2771 bool &SizeIsNegative, 2772 llvm::APSInt &Oversized) { 2773 // This method tries to turn a variable array into a constant 2774 // array even when the size isn't an ICE. This is necessary 2775 // for compatibility with code that depends on gcc's buggy 2776 // constant expression folding, like struct {char x[(int)(char*)2];} 2777 SizeIsNegative = false; 2778 Oversized = 0; 2779 2780 if (T->isDependentType()) 2781 return QualType(); 2782 2783 QualifierCollector Qs; 2784 const Type *Ty = Qs.strip(T); 2785 2786 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2787 QualType Pointee = PTy->getPointeeType(); 2788 QualType FixedType = 2789 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2790 Oversized); 2791 if (FixedType.isNull()) return FixedType; 2792 FixedType = Context.getPointerType(FixedType); 2793 return Qs.apply(Context, FixedType); 2794 } 2795 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 2796 QualType Inner = PTy->getInnerType(); 2797 QualType FixedType = 2798 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 2799 Oversized); 2800 if (FixedType.isNull()) return FixedType; 2801 FixedType = Context.getParenType(FixedType); 2802 return Qs.apply(Context, FixedType); 2803 } 2804 2805 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2806 if (!VLATy) 2807 return QualType(); 2808 // FIXME: We should probably handle this case 2809 if (VLATy->getElementType()->isVariablyModifiedType()) 2810 return QualType(); 2811 2812 Expr::EvalResult EvalResult; 2813 if (!VLATy->getSizeExpr() || 2814 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2815 !EvalResult.Val.isInt()) 2816 return QualType(); 2817 2818 // Check whether the array size is negative. 2819 llvm::APSInt &Res = EvalResult.Val.getInt(); 2820 if (Res.isSigned() && Res.isNegative()) { 2821 SizeIsNegative = true; 2822 return QualType(); 2823 } 2824 2825 // Check whether the array is too large to be addressed. 2826 unsigned ActiveSizeBits 2827 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2828 Res); 2829 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2830 Oversized = Res; 2831 return QualType(); 2832 } 2833 2834 return Context.getConstantArrayType(VLATy->getElementType(), 2835 Res, ArrayType::Normal, 0); 2836} 2837 2838/// \brief Register the given locally-scoped external C declaration so 2839/// that it can be found later for redeclarations 2840void 2841Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2842 const LookupResult &Previous, 2843 Scope *S) { 2844 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2845 "Decl is not a locally-scoped decl!"); 2846 // Note that we have a locally-scoped external with this name. 2847 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2848 2849 if (!Previous.isSingleResult()) 2850 return; 2851 2852 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2853 2854 // If there was a previous declaration of this variable, it may be 2855 // in our identifier chain. Update the identifier chain with the new 2856 // declaration. 2857 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2858 // The previous declaration was found on the identifer resolver 2859 // chain, so remove it from its scope. 2860 while (S && !S->isDeclScope(PrevDecl)) 2861 S = S->getParent(); 2862 2863 if (S) 2864 S->RemoveDecl(PrevDecl); 2865 } 2866} 2867 2868/// \brief Diagnose function specifiers on a declaration of an identifier that 2869/// does not identify a function. 2870void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2871 // FIXME: We should probably indicate the identifier in question to avoid 2872 // confusion for constructs like "inline int a(), b;" 2873 if (D.getDeclSpec().isInlineSpecified()) 2874 Diag(D.getDeclSpec().getInlineSpecLoc(), 2875 diag::err_inline_non_function); 2876 2877 if (D.getDeclSpec().isVirtualSpecified()) 2878 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2879 diag::err_virtual_non_function); 2880 2881 if (D.getDeclSpec().isExplicitSpecified()) 2882 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2883 diag::err_explicit_non_function); 2884} 2885 2886NamedDecl* 2887Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2888 QualType R, TypeSourceInfo *TInfo, 2889 LookupResult &Previous, bool &Redeclaration) { 2890 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2891 if (D.getCXXScopeSpec().isSet()) { 2892 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2893 << D.getCXXScopeSpec().getRange(); 2894 D.setInvalidType(); 2895 // Pretend we didn't see the scope specifier. 2896 DC = CurContext; 2897 Previous.clear(); 2898 } 2899 2900 if (getLangOptions().CPlusPlus) { 2901 // Check that there are no default arguments (C++ only). 2902 CheckExtraCXXDefaultArguments(D); 2903 } 2904 2905 DiagnoseFunctionSpecifiers(D); 2906 2907 if (D.getDeclSpec().isThreadSpecified()) 2908 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2909 2910 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2911 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2912 << D.getName().getSourceRange(); 2913 return 0; 2914 } 2915 2916 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2917 if (!NewTD) return 0; 2918 2919 // Handle attributes prior to checking for duplicates in MergeVarDecl 2920 ProcessDeclAttributes(S, NewTD, D); 2921 2922 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2923 // then it shall have block scope. 2924 // Note that variably modified types must be fixed before merging the decl so 2925 // that redeclarations will match. 2926 QualType T = NewTD->getUnderlyingType(); 2927 if (T->isVariablyModifiedType()) { 2928 getCurFunction()->setHasBranchProtectedScope(); 2929 2930 if (S->getFnParent() == 0) { 2931 bool SizeIsNegative; 2932 llvm::APSInt Oversized; 2933 QualType FixedTy = 2934 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2935 Oversized); 2936 if (!FixedTy.isNull()) { 2937 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2938 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2939 } else { 2940 if (SizeIsNegative) 2941 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2942 else if (T->isVariableArrayType()) 2943 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2944 else if (Oversized.getBoolValue()) 2945 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2946 << Oversized.toString(10); 2947 else 2948 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2949 NewTD->setInvalidDecl(); 2950 } 2951 } 2952 } 2953 2954 // Merge the decl with the existing one if appropriate. If the decl is 2955 // in an outer scope, it isn't the same thing. 2956 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false, 2957 /*ExplicitInstantiationOrSpecialization=*/false); 2958 if (!Previous.empty()) { 2959 Redeclaration = true; 2960 MergeTypeDefDecl(NewTD, Previous); 2961 } 2962 2963 // If this is the C FILE type, notify the AST context. 2964 if (IdentifierInfo *II = NewTD->getIdentifier()) 2965 if (!NewTD->isInvalidDecl() && 2966 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2967 if (II->isStr("FILE")) 2968 Context.setFILEDecl(NewTD); 2969 else if (II->isStr("jmp_buf")) 2970 Context.setjmp_bufDecl(NewTD); 2971 else if (II->isStr("sigjmp_buf")) 2972 Context.setsigjmp_bufDecl(NewTD); 2973 else if (II->isStr("__builtin_va_list")) 2974 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2975 } 2976 2977 return NewTD; 2978} 2979 2980/// \brief Determines whether the given declaration is an out-of-scope 2981/// previous declaration. 2982/// 2983/// This routine should be invoked when name lookup has found a 2984/// previous declaration (PrevDecl) that is not in the scope where a 2985/// new declaration by the same name is being introduced. If the new 2986/// declaration occurs in a local scope, previous declarations with 2987/// linkage may still be considered previous declarations (C99 2988/// 6.2.2p4-5, C++ [basic.link]p6). 2989/// 2990/// \param PrevDecl the previous declaration found by name 2991/// lookup 2992/// 2993/// \param DC the context in which the new declaration is being 2994/// declared. 2995/// 2996/// \returns true if PrevDecl is an out-of-scope previous declaration 2997/// for a new delcaration with the same name. 2998static bool 2999isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 3000 ASTContext &Context) { 3001 if (!PrevDecl) 3002 return false; 3003 3004 if (!PrevDecl->hasLinkage()) 3005 return false; 3006 3007 if (Context.getLangOptions().CPlusPlus) { 3008 // C++ [basic.link]p6: 3009 // If there is a visible declaration of an entity with linkage 3010 // having the same name and type, ignoring entities declared 3011 // outside the innermost enclosing namespace scope, the block 3012 // scope declaration declares that same entity and receives the 3013 // linkage of the previous declaration. 3014 DeclContext *OuterContext = DC->getRedeclContext(); 3015 if (!OuterContext->isFunctionOrMethod()) 3016 // This rule only applies to block-scope declarations. 3017 return false; 3018 3019 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 3020 if (PrevOuterContext->isRecord()) 3021 // We found a member function: ignore it. 3022 return false; 3023 3024 // Find the innermost enclosing namespace for the new and 3025 // previous declarations. 3026 OuterContext = OuterContext->getEnclosingNamespaceContext(); 3027 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 3028 3029 // The previous declaration is in a different namespace, so it 3030 // isn't the same function. 3031 if (!OuterContext->Equals(PrevOuterContext)) 3032 return false; 3033 } 3034 3035 return true; 3036} 3037 3038static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 3039 CXXScopeSpec &SS = D.getCXXScopeSpec(); 3040 if (!SS.isSet()) return; 3041 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 3042} 3043 3044NamedDecl* 3045Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 3046 QualType R, TypeSourceInfo *TInfo, 3047 LookupResult &Previous, 3048 MultiTemplateParamsArg TemplateParamLists, 3049 bool &Redeclaration) { 3050 DeclarationName Name = GetNameForDeclarator(D).getName(); 3051 3052 // Check that there are no default arguments (C++ only). 3053 if (getLangOptions().CPlusPlus) 3054 CheckExtraCXXDefaultArguments(D); 3055 3056 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 3057 assert(SCSpec != DeclSpec::SCS_typedef && 3058 "Parser allowed 'typedef' as storage class VarDecl."); 3059 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 3060 if (SCSpec == DeclSpec::SCS_mutable) { 3061 // mutable can only appear on non-static class members, so it's always 3062 // an error here 3063 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 3064 D.setInvalidType(); 3065 SC = SC_None; 3066 } 3067 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3068 VarDecl::StorageClass SCAsWritten 3069 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3070 3071 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3072 if (!II) { 3073 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3074 << Name.getAsString(); 3075 return 0; 3076 } 3077 3078 DiagnoseFunctionSpecifiers(D); 3079 3080 if (!DC->isRecord() && S->getFnParent() == 0) { 3081 // C99 6.9p2: The storage-class specifiers auto and register shall not 3082 // appear in the declaration specifiers in an external declaration. 3083 if (SC == SC_Auto || SC == SC_Register) { 3084 3085 // If this is a register variable with an asm label specified, then this 3086 // is a GNU extension. 3087 if (SC == SC_Register && D.getAsmLabel()) 3088 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3089 else 3090 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3091 D.setInvalidType(); 3092 } 3093 } 3094 3095 bool isExplicitSpecialization = false; 3096 VarDecl *NewVD; 3097 if (!getLangOptions().CPlusPlus) { 3098 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3099 D.getIdentifierLoc(), II, 3100 R, TInfo, SC, SCAsWritten); 3101 3102 if (D.isInvalidType()) 3103 NewVD->setInvalidDecl(); 3104 } else { 3105 if (DC->isRecord() && !CurContext->isRecord()) { 3106 // This is an out-of-line definition of a static data member. 3107 if (SC == SC_Static) { 3108 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3109 diag::err_static_out_of_line) 3110 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3111 } else if (SC == SC_None) 3112 SC = SC_Static; 3113 } 3114 if (SC == SC_Static) { 3115 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3116 if (RD->isLocalClass()) 3117 Diag(D.getIdentifierLoc(), 3118 diag::err_static_data_member_not_allowed_in_local_class) 3119 << Name << RD->getDeclName(); 3120 3121 // C++ [class.union]p1: If a union contains a static data member, 3122 // the program is ill-formed. 3123 // 3124 // We also disallow static data members in anonymous structs. 3125 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3126 Diag(D.getIdentifierLoc(), 3127 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3128 << Name << RD->isUnion(); 3129 } 3130 } 3131 3132 // Match up the template parameter lists with the scope specifier, then 3133 // determine whether we have a template or a template specialization. 3134 isExplicitSpecialization = false; 3135 bool Invalid = false; 3136 if (TemplateParameterList *TemplateParams 3137 = MatchTemplateParametersToScopeSpecifier( 3138 D.getDeclSpec().getSourceRange().getBegin(), 3139 D.getCXXScopeSpec(), 3140 TemplateParamLists.get(), 3141 TemplateParamLists.size(), 3142 /*never a friend*/ false, 3143 isExplicitSpecialization, 3144 Invalid)) { 3145 if (TemplateParams->size() > 0) { 3146 // There is no such thing as a variable template. 3147 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3148 << II 3149 << SourceRange(TemplateParams->getTemplateLoc(), 3150 TemplateParams->getRAngleLoc()); 3151 return 0; 3152 } else { 3153 // There is an extraneous 'template<>' for this variable. Complain 3154 // about it, but allow the declaration of the variable. 3155 Diag(TemplateParams->getTemplateLoc(), 3156 diag::err_template_variable_noparams) 3157 << II 3158 << SourceRange(TemplateParams->getTemplateLoc(), 3159 TemplateParams->getRAngleLoc()); 3160 isExplicitSpecialization = true; 3161 } 3162 } 3163 3164 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3165 D.getIdentifierLoc(), II, 3166 R, TInfo, SC, SCAsWritten); 3167 3168 // If this decl has an auto type in need of deduction, make a note of the 3169 // Decl so we can diagnose uses of it in its own initializer. 3170 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3171 R->getContainedAutoType()) 3172 ParsingInitForAutoVars.insert(NewVD); 3173 3174 if (D.isInvalidType() || Invalid) 3175 NewVD->setInvalidDecl(); 3176 3177 SetNestedNameSpecifier(NewVD, D); 3178 3179 if (TemplateParamLists.size() > 0 && D.getCXXScopeSpec().isSet()) { 3180 NewVD->setTemplateParameterListsInfo(Context, 3181 TemplateParamLists.size(), 3182 TemplateParamLists.release()); 3183 } 3184 } 3185 3186 if (D.getDeclSpec().isThreadSpecified()) { 3187 if (NewVD->hasLocalStorage()) 3188 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3189 else if (!Context.Target.isTLSSupported()) 3190 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3191 else 3192 NewVD->setThreadSpecified(true); 3193 } 3194 3195 // Set the lexical context. If the declarator has a C++ scope specifier, the 3196 // lexical context will be different from the semantic context. 3197 NewVD->setLexicalDeclContext(CurContext); 3198 3199 // Handle attributes prior to checking for duplicates in MergeVarDecl 3200 ProcessDeclAttributes(S, NewVD, D); 3201 3202 // Handle GNU asm-label extension (encoded as an attribute). 3203 if (Expr *E = (Expr*)D.getAsmLabel()) { 3204 // The parser guarantees this is a string. 3205 StringLiteral *SE = cast<StringLiteral>(E); 3206 llvm::StringRef Label = SE->getString(); 3207 if (S->getFnParent() != 0) { 3208 switch (SC) { 3209 case SC_None: 3210 case SC_Auto: 3211 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3212 break; 3213 case SC_Register: 3214 if (!Context.Target.isValidGCCRegisterName(Label)) 3215 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3216 break; 3217 case SC_Static: 3218 case SC_Extern: 3219 case SC_PrivateExtern: 3220 break; 3221 } 3222 } 3223 3224 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3225 Context, Label)); 3226 } 3227 3228 // Diagnose shadowed variables before filtering for scope. 3229 if (!D.getCXXScopeSpec().isSet()) 3230 CheckShadow(S, NewVD, Previous); 3231 3232 // Don't consider existing declarations that are in a different 3233 // scope and are out-of-semantic-context declarations (if the new 3234 // declaration has linkage). 3235 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage(), 3236 isExplicitSpecialization); 3237 3238 if (!getLangOptions().CPlusPlus) 3239 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3240 else { 3241 // Merge the decl with the existing one if appropriate. 3242 if (!Previous.empty()) { 3243 if (Previous.isSingleResult() && 3244 isa<FieldDecl>(Previous.getFoundDecl()) && 3245 D.getCXXScopeSpec().isSet()) { 3246 // The user tried to define a non-static data member 3247 // out-of-line (C++ [dcl.meaning]p1). 3248 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3249 << D.getCXXScopeSpec().getRange(); 3250 Previous.clear(); 3251 NewVD->setInvalidDecl(); 3252 } 3253 } else if (D.getCXXScopeSpec().isSet()) { 3254 // No previous declaration in the qualifying scope. 3255 Diag(D.getIdentifierLoc(), diag::err_no_member) 3256 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3257 << D.getCXXScopeSpec().getRange(); 3258 NewVD->setInvalidDecl(); 3259 } 3260 3261 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3262 3263 // This is an explicit specialization of a static data member. Check it. 3264 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3265 CheckMemberSpecialization(NewVD, Previous)) 3266 NewVD->setInvalidDecl(); 3267 } 3268 3269 // attributes declared post-definition are currently ignored 3270 // FIXME: This should be handled in attribute merging, not 3271 // here. 3272 if (Previous.isSingleResult()) { 3273 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3274 if (Def && (Def = Def->getDefinition()) && 3275 Def != NewVD && D.hasAttributes()) { 3276 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3277 Diag(Def->getLocation(), diag::note_previous_definition); 3278 } 3279 } 3280 3281 // If this is a locally-scoped extern C variable, update the map of 3282 // such variables. 3283 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3284 !NewVD->isInvalidDecl()) 3285 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3286 3287 // If there's a #pragma GCC visibility in scope, and this isn't a class 3288 // member, set the visibility of this variable. 3289 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3290 AddPushedVisibilityAttribute(NewVD); 3291 3292 MarkUnusedFileScopedDecl(NewVD); 3293 3294 return NewVD; 3295} 3296 3297/// \brief Diagnose variable or built-in function shadowing. Implements 3298/// -Wshadow. 3299/// 3300/// This method is called whenever a VarDecl is added to a "useful" 3301/// scope. 3302/// 3303/// \param S the scope in which the shadowing name is being declared 3304/// \param R the lookup of the name 3305/// 3306void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3307 // Return if warning is ignored. 3308 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3309 Diagnostic::Ignored) 3310 return; 3311 3312 // Don't diagnose declarations at file scope. 3313 DeclContext *NewDC = D->getDeclContext(); 3314 if (NewDC->isFileContext()) 3315 return; 3316 3317 // Only diagnose if we're shadowing an unambiguous field or variable. 3318 if (R.getResultKind() != LookupResult::Found) 3319 return; 3320 3321 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3322 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3323 return; 3324 3325 // Fields are not shadowed by variables in C++ static methods. 3326 if (isa<FieldDecl>(ShadowedDecl)) 3327 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3328 if (MD->isStatic()) 3329 return; 3330 3331 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3332 if (shadowedVar->isExternC()) { 3333 // Don't warn for this case: 3334 // 3335 // @code 3336 // extern int bob; 3337 // void f() { 3338 // extern int bob; 3339 // } 3340 // @endcode 3341 if (D->isExternC()) 3342 return; 3343 3344 // For shadowing external vars, make sure that we point to the global 3345 // declaration, not a locally scoped extern declaration. 3346 for (VarDecl::redecl_iterator 3347 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3348 I != E; ++I) 3349 if (I->isFileVarDecl()) { 3350 ShadowedDecl = *I; 3351 break; 3352 } 3353 } 3354 3355 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3356 3357 // Only warn about certain kinds of shadowing for class members. 3358 if (NewDC && NewDC->isRecord()) { 3359 // In particular, don't warn about shadowing non-class members. 3360 if (!OldDC->isRecord()) 3361 return; 3362 3363 // TODO: should we warn about static data members shadowing 3364 // static data members from base classes? 3365 3366 // TODO: don't diagnose for inaccessible shadowed members. 3367 // This is hard to do perfectly because we might friend the 3368 // shadowing context, but that's just a false negative. 3369 } 3370 3371 // Determine what kind of declaration we're shadowing. 3372 unsigned Kind; 3373 if (isa<RecordDecl>(OldDC)) { 3374 if (isa<FieldDecl>(ShadowedDecl)) 3375 Kind = 3; // field 3376 else 3377 Kind = 2; // static data member 3378 } else if (OldDC->isFileContext()) 3379 Kind = 1; // global 3380 else 3381 Kind = 0; // local 3382 3383 DeclarationName Name = R.getLookupName(); 3384 3385 // Emit warning and note. 3386 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3387 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3388} 3389 3390/// \brief Check -Wshadow without the advantage of a previous lookup. 3391void Sema::CheckShadow(Scope *S, VarDecl *D) { 3392 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3393 Diagnostic::Ignored) 3394 return; 3395 3396 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3397 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3398 LookupName(R, S); 3399 CheckShadow(S, D, R); 3400} 3401 3402/// \brief Perform semantic checking on a newly-created variable 3403/// declaration. 3404/// 3405/// This routine performs all of the type-checking required for a 3406/// variable declaration once it has been built. It is used both to 3407/// check variables after they have been parsed and their declarators 3408/// have been translated into a declaration, and to check variables 3409/// that have been instantiated from a template. 3410/// 3411/// Sets NewVD->isInvalidDecl() if an error was encountered. 3412void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3413 LookupResult &Previous, 3414 bool &Redeclaration) { 3415 // If the decl is already known invalid, don't check it. 3416 if (NewVD->isInvalidDecl()) 3417 return; 3418 3419 QualType T = NewVD->getType(); 3420 3421 if (T->isObjCObjectType()) { 3422 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3423 return NewVD->setInvalidDecl(); 3424 } 3425 3426 // Emit an error if an address space was applied to decl with local storage. 3427 // This includes arrays of objects with address space qualifiers, but not 3428 // automatic variables that point to other address spaces. 3429 // ISO/IEC TR 18037 S5.1.2 3430 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3431 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3432 return NewVD->setInvalidDecl(); 3433 } 3434 3435 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3436 && !NewVD->hasAttr<BlocksAttr>()) 3437 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3438 3439 bool isVM = T->isVariablyModifiedType(); 3440 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3441 NewVD->hasAttr<BlocksAttr>()) 3442 getCurFunction()->setHasBranchProtectedScope(); 3443 3444 if ((isVM && NewVD->hasLinkage()) || 3445 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3446 bool SizeIsNegative; 3447 llvm::APSInt Oversized; 3448 QualType FixedTy = 3449 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3450 Oversized); 3451 3452 if (FixedTy.isNull() && T->isVariableArrayType()) { 3453 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3454 // FIXME: This won't give the correct result for 3455 // int a[10][n]; 3456 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3457 3458 if (NewVD->isFileVarDecl()) 3459 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3460 << SizeRange; 3461 else if (NewVD->getStorageClass() == SC_Static) 3462 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3463 << SizeRange; 3464 else 3465 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3466 << SizeRange; 3467 return NewVD->setInvalidDecl(); 3468 } 3469 3470 if (FixedTy.isNull()) { 3471 if (NewVD->isFileVarDecl()) 3472 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3473 else 3474 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3475 return NewVD->setInvalidDecl(); 3476 } 3477 3478 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3479 NewVD->setType(FixedTy); 3480 } 3481 3482 if (Previous.empty() && NewVD->isExternC()) { 3483 // Since we did not find anything by this name and we're declaring 3484 // an extern "C" variable, look for a non-visible extern "C" 3485 // declaration with the same name. 3486 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3487 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3488 if (Pos != LocallyScopedExternalDecls.end()) 3489 Previous.addDecl(Pos->second); 3490 } 3491 3492 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3493 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3494 << T; 3495 return NewVD->setInvalidDecl(); 3496 } 3497 3498 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3499 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3500 return NewVD->setInvalidDecl(); 3501 } 3502 3503 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3504 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3505 return NewVD->setInvalidDecl(); 3506 } 3507 3508 // Function pointers and references cannot have qualified function type, only 3509 // function pointer-to-members can do that. 3510 QualType Pointee; 3511 unsigned PtrOrRef = 0; 3512 if (const PointerType *Ptr = T->getAs<PointerType>()) 3513 Pointee = Ptr->getPointeeType(); 3514 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3515 Pointee = Ref->getPointeeType(); 3516 PtrOrRef = 1; 3517 } 3518 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3519 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3520 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3521 << PtrOrRef; 3522 return NewVD->setInvalidDecl(); 3523 } 3524 3525 if (!Previous.empty()) { 3526 Redeclaration = true; 3527 MergeVarDecl(NewVD, Previous); 3528 } 3529} 3530 3531/// \brief Data used with FindOverriddenMethod 3532struct FindOverriddenMethodData { 3533 Sema *S; 3534 CXXMethodDecl *Method; 3535}; 3536 3537/// \brief Member lookup function that determines whether a given C++ 3538/// method overrides a method in a base class, to be used with 3539/// CXXRecordDecl::lookupInBases(). 3540static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3541 CXXBasePath &Path, 3542 void *UserData) { 3543 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3544 3545 FindOverriddenMethodData *Data 3546 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3547 3548 DeclarationName Name = Data->Method->getDeclName(); 3549 3550 // FIXME: Do we care about other names here too? 3551 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3552 // We really want to find the base class destructor here. 3553 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3554 CanQualType CT = Data->S->Context.getCanonicalType(T); 3555 3556 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3557 } 3558 3559 for (Path.Decls = BaseRecord->lookup(Name); 3560 Path.Decls.first != Path.Decls.second; 3561 ++Path.Decls.first) { 3562 NamedDecl *D = *Path.Decls.first; 3563 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3564 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3565 return true; 3566 } 3567 } 3568 3569 return false; 3570} 3571 3572/// AddOverriddenMethods - See if a method overrides any in the base classes, 3573/// and if so, check that it's a valid override and remember it. 3574bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3575 // Look for virtual methods in base classes that this method might override. 3576 CXXBasePaths Paths; 3577 FindOverriddenMethodData Data; 3578 Data.Method = MD; 3579 Data.S = this; 3580 bool AddedAny = false; 3581 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3582 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3583 E = Paths.found_decls_end(); I != E; ++I) { 3584 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3585 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3586 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3587 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 3588 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3589 AddedAny = true; 3590 } 3591 } 3592 } 3593 } 3594 3595 return AddedAny; 3596} 3597 3598static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3599 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3600 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3601 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3602 assert(!Prev.isAmbiguous() && 3603 "Cannot have an ambiguity in previous-declaration lookup"); 3604 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3605 Func != FuncEnd; ++Func) { 3606 if (isa<FunctionDecl>(*Func) && 3607 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3608 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3609 } 3610} 3611 3612NamedDecl* 3613Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3614 QualType R, TypeSourceInfo *TInfo, 3615 LookupResult &Previous, 3616 MultiTemplateParamsArg TemplateParamLists, 3617 bool IsFunctionDefinition, bool &Redeclaration) { 3618 assert(R.getTypePtr()->isFunctionType()); 3619 3620 // TODO: consider using NameInfo for diagnostic. 3621 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3622 DeclarationName Name = NameInfo.getName(); 3623 FunctionDecl::StorageClass SC = SC_None; 3624 switch (D.getDeclSpec().getStorageClassSpec()) { 3625 default: assert(0 && "Unknown storage class!"); 3626 case DeclSpec::SCS_auto: 3627 case DeclSpec::SCS_register: 3628 case DeclSpec::SCS_mutable: 3629 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3630 diag::err_typecheck_sclass_func); 3631 D.setInvalidType(); 3632 break; 3633 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3634 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3635 case DeclSpec::SCS_static: { 3636 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3637 // C99 6.7.1p5: 3638 // The declaration of an identifier for a function that has 3639 // block scope shall have no explicit storage-class specifier 3640 // other than extern 3641 // See also (C++ [dcl.stc]p4). 3642 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3643 diag::err_static_block_func); 3644 SC = SC_None; 3645 } else 3646 SC = SC_Static; 3647 break; 3648 } 3649 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3650 } 3651 3652 if (D.getDeclSpec().isThreadSpecified()) 3653 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3654 3655 // Do not allow returning a objc interface by-value. 3656 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3657 Diag(D.getIdentifierLoc(), 3658 diag::err_object_cannot_be_passed_returned_by_value) << 0 3659 << R->getAs<FunctionType>()->getResultType(); 3660 D.setInvalidType(); 3661 } 3662 3663 FunctionDecl *NewFD; 3664 bool isInline = D.getDeclSpec().isInlineSpecified(); 3665 bool isFriend = false; 3666 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3667 FunctionDecl::StorageClass SCAsWritten 3668 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3669 FunctionTemplateDecl *FunctionTemplate = 0; 3670 bool isExplicitSpecialization = false; 3671 bool isFunctionTemplateSpecialization = false; 3672 3673 if (!getLangOptions().CPlusPlus) { 3674 // Determine whether the function was written with a 3675 // prototype. This true when: 3676 // - there is a prototype in the declarator, or 3677 // - the type R of the function is some kind of typedef or other reference 3678 // to a type name (which eventually refers to a function type). 3679 bool HasPrototype = 3680 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 3681 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3682 3683 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3684 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3685 HasPrototype); 3686 if (D.isInvalidType()) 3687 NewFD->setInvalidDecl(); 3688 3689 // Set the lexical context. 3690 NewFD->setLexicalDeclContext(CurContext); 3691 // Filter out previous declarations that don't match the scope. 3692 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage(), 3693 /*ExplicitInstantiationOrSpecialization=*/false); 3694 } else { 3695 isFriend = D.getDeclSpec().isFriendSpecified(); 3696 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3697 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3698 bool isVirtualOkay = false; 3699 3700 // Check that the return type is not an abstract class type. 3701 // For record types, this is done by the AbstractClassUsageDiagnoser once 3702 // the class has been completely parsed. 3703 if (!DC->isRecord() && 3704 RequireNonAbstractType(D.getIdentifierLoc(), 3705 R->getAs<FunctionType>()->getResultType(), 3706 diag::err_abstract_type_in_decl, 3707 AbstractReturnType)) 3708 D.setInvalidType(); 3709 3710 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3711 // This is a C++ constructor declaration. 3712 assert(DC->isRecord() && 3713 "Constructors can only be declared in a member context"); 3714 3715 R = CheckConstructorDeclarator(D, R, SC); 3716 3717 // Create the new declaration 3718 NewFD = CXXConstructorDecl::Create(Context, 3719 cast<CXXRecordDecl>(DC), 3720 D.getSourceRange().getBegin(), 3721 NameInfo, R, TInfo, 3722 isExplicit, isInline, 3723 /*isImplicitlyDeclared=*/false); 3724 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3725 // This is a C++ destructor declaration. 3726 if (DC->isRecord()) { 3727 R = CheckDestructorDeclarator(D, R, SC); 3728 3729 NewFD = CXXDestructorDecl::Create(Context, 3730 cast<CXXRecordDecl>(DC), 3731 D.getSourceRange().getBegin(), 3732 NameInfo, R, TInfo, 3733 isInline, 3734 /*isImplicitlyDeclared=*/false); 3735 isVirtualOkay = true; 3736 } else { 3737 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3738 3739 // Create a FunctionDecl to satisfy the function definition parsing 3740 // code path. 3741 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3742 D.getIdentifierLoc(), Name, R, TInfo, 3743 SC, SCAsWritten, isInline, 3744 /*hasPrototype=*/true); 3745 D.setInvalidType(); 3746 } 3747 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3748 if (!DC->isRecord()) { 3749 Diag(D.getIdentifierLoc(), 3750 diag::err_conv_function_not_member); 3751 return 0; 3752 } 3753 3754 CheckConversionDeclarator(D, R, SC); 3755 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3756 D.getSourceRange().getBegin(), 3757 NameInfo, R, TInfo, 3758 isInline, isExplicit, 3759 SourceLocation()); 3760 3761 isVirtualOkay = true; 3762 } else if (DC->isRecord()) { 3763 // If the of the function is the same as the name of the record, then this 3764 // must be an invalid constructor that has a return type. 3765 // (The parser checks for a return type and makes the declarator a 3766 // constructor if it has no return type). 3767 // must have an invalid constructor that has a return type 3768 if (Name.getAsIdentifierInfo() && 3769 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3770 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3771 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3772 << SourceRange(D.getIdentifierLoc()); 3773 return 0; 3774 } 3775 3776 bool isStatic = SC == SC_Static; 3777 3778 // [class.free]p1: 3779 // Any allocation function for a class T is a static member 3780 // (even if not explicitly declared static). 3781 if (Name.getCXXOverloadedOperator() == OO_New || 3782 Name.getCXXOverloadedOperator() == OO_Array_New) 3783 isStatic = true; 3784 3785 // [class.free]p6 Any deallocation function for a class X is a static member 3786 // (even if not explicitly declared static). 3787 if (Name.getCXXOverloadedOperator() == OO_Delete || 3788 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3789 isStatic = true; 3790 3791 // This is a C++ method declaration. 3792 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3793 D.getSourceRange().getBegin(), 3794 NameInfo, R, TInfo, 3795 isStatic, SCAsWritten, isInline, 3796 SourceLocation()); 3797 3798 isVirtualOkay = !isStatic; 3799 } else { 3800 // Determine whether the function was written with a 3801 // prototype. This true when: 3802 // - we're in C++ (where every function has a prototype), 3803 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3804 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3805 true/*HasPrototype*/); 3806 } 3807 3808 if (isFriend && !isInline && IsFunctionDefinition) { 3809 // C++ [class.friend]p5 3810 // A function can be defined in a friend declaration of a 3811 // class . . . . Such a function is implicitly inline. 3812 NewFD->setImplicitlyInline(); 3813 } 3814 3815 SetNestedNameSpecifier(NewFD, D); 3816 isExplicitSpecialization = false; 3817 isFunctionTemplateSpecialization = false; 3818 if (D.isInvalidType()) 3819 NewFD->setInvalidDecl(); 3820 3821 // Set the lexical context. If the declarator has a C++ 3822 // scope specifier, or is the object of a friend declaration, the 3823 // lexical context will be different from the semantic context. 3824 NewFD->setLexicalDeclContext(CurContext); 3825 3826 // Match up the template parameter lists with the scope specifier, then 3827 // determine whether we have a template or a template specialization. 3828 bool Invalid = false; 3829 if (TemplateParameterList *TemplateParams 3830 = MatchTemplateParametersToScopeSpecifier( 3831 D.getDeclSpec().getSourceRange().getBegin(), 3832 D.getCXXScopeSpec(), 3833 TemplateParamLists.get(), 3834 TemplateParamLists.size(), 3835 isFriend, 3836 isExplicitSpecialization, 3837 Invalid)) { 3838 if (TemplateParams->size() > 0) { 3839 // This is a function template 3840 3841 // Check that we can declare a template here. 3842 if (CheckTemplateDeclScope(S, TemplateParams)) 3843 return 0; 3844 3845 // A destructor cannot be a template. 3846 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3847 Diag(NewFD->getLocation(), diag::err_destructor_template); 3848 return 0; 3849 } 3850 3851 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3852 NewFD->getLocation(), 3853 Name, TemplateParams, 3854 NewFD); 3855 FunctionTemplate->setLexicalDeclContext(CurContext); 3856 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3857 3858 // For source fidelity, store the other template param lists. 3859 if (TemplateParamLists.size() > 1) { 3860 NewFD->setTemplateParameterListsInfo(Context, 3861 TemplateParamLists.size() - 1, 3862 TemplateParamLists.release()); 3863 } 3864 } else { 3865 // This is a function template specialization. 3866 isFunctionTemplateSpecialization = true; 3867 // For source fidelity, store all the template param lists. 3868 NewFD->setTemplateParameterListsInfo(Context, 3869 TemplateParamLists.size(), 3870 TemplateParamLists.release()); 3871 3872 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3873 if (isFriend) { 3874 // We want to remove the "template<>", found here. 3875 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3876 3877 // If we remove the template<> and the name is not a 3878 // template-id, we're actually silently creating a problem: 3879 // the friend declaration will refer to an untemplated decl, 3880 // and clearly the user wants a template specialization. So 3881 // we need to insert '<>' after the name. 3882 SourceLocation InsertLoc; 3883 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3884 InsertLoc = D.getName().getSourceRange().getEnd(); 3885 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3886 } 3887 3888 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3889 << Name << RemoveRange 3890 << FixItHint::CreateRemoval(RemoveRange) 3891 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3892 } 3893 } 3894 } 3895 else { 3896 // All template param lists were matched against the scope specifier: 3897 // this is NOT (an explicit specialization of) a template. 3898 if (TemplateParamLists.size() > 0) 3899 // For source fidelity, store all the template param lists. 3900 NewFD->setTemplateParameterListsInfo(Context, 3901 TemplateParamLists.size(), 3902 TemplateParamLists.release()); 3903 } 3904 3905 if (Invalid) { 3906 NewFD->setInvalidDecl(); 3907 if (FunctionTemplate) 3908 FunctionTemplate->setInvalidDecl(); 3909 } 3910 3911 // C++ [dcl.fct.spec]p5: 3912 // The virtual specifier shall only be used in declarations of 3913 // nonstatic class member functions that appear within a 3914 // member-specification of a class declaration; see 10.3. 3915 // 3916 if (isVirtual && !NewFD->isInvalidDecl()) { 3917 if (!isVirtualOkay) { 3918 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3919 diag::err_virtual_non_function); 3920 } else if (!CurContext->isRecord()) { 3921 // 'virtual' was specified outside of the class. 3922 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3923 diag::err_virtual_out_of_class) 3924 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3925 } else if (NewFD->getDescribedFunctionTemplate()) { 3926 // C++ [temp.mem]p3: 3927 // A member function template shall not be virtual. 3928 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3929 diag::err_virtual_member_function_template) 3930 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3931 } else { 3932 // Okay: Add virtual to the method. 3933 NewFD->setVirtualAsWritten(true); 3934 } 3935 } 3936 3937 // C++ [dcl.fct.spec]p3: 3938 // The inline specifier shall not appear on a block scope function declaration. 3939 if (isInline && !NewFD->isInvalidDecl()) { 3940 if (CurContext->isFunctionOrMethod()) { 3941 // 'inline' is not allowed on block scope function declaration. 3942 Diag(D.getDeclSpec().getInlineSpecLoc(), 3943 diag::err_inline_declaration_block_scope) << Name 3944 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3945 } 3946 } 3947 3948 // C++ [dcl.fct.spec]p6: 3949 // The explicit specifier shall be used only in the declaration of a 3950 // constructor or conversion function within its class definition; see 12.3.1 3951 // and 12.3.2. 3952 if (isExplicit && !NewFD->isInvalidDecl()) { 3953 if (!CurContext->isRecord()) { 3954 // 'explicit' was specified outside of the class. 3955 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3956 diag::err_explicit_out_of_class) 3957 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3958 } else if (!isa<CXXConstructorDecl>(NewFD) && 3959 !isa<CXXConversionDecl>(NewFD)) { 3960 // 'explicit' was specified on a function that wasn't a constructor 3961 // or conversion function. 3962 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3963 diag::err_explicit_non_ctor_or_conv_function) 3964 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3965 } 3966 } 3967 3968 // Filter out previous declarations that don't match the scope. 3969 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage(), 3970 isExplicitSpecialization || 3971 isFunctionTemplateSpecialization); 3972 3973 if (isFriend) { 3974 // For now, claim that the objects have no previous declaration. 3975 if (FunctionTemplate) { 3976 FunctionTemplate->setObjectOfFriendDecl(false); 3977 FunctionTemplate->setAccess(AS_public); 3978 } 3979 NewFD->setObjectOfFriendDecl(false); 3980 NewFD->setAccess(AS_public); 3981 } 3982 3983 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 3984 // A method is implicitly inline if it's defined in its class 3985 // definition. 3986 NewFD->setImplicitlyInline(); 3987 } 3988 3989 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3990 !CurContext->isRecord()) { 3991 // C++ [class.static]p1: 3992 // A data or function member of a class may be declared static 3993 // in a class definition, in which case it is a static member of 3994 // the class. 3995 3996 // Complain about the 'static' specifier if it's on an out-of-line 3997 // member function definition. 3998 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3999 diag::err_static_out_of_line) 4000 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4001 } 4002 } 4003 4004 // Handle GNU asm-label extension (encoded as an attribute). 4005 if (Expr *E = (Expr*) D.getAsmLabel()) { 4006 // The parser guarantees this is a string. 4007 StringLiteral *SE = cast<StringLiteral>(E); 4008 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 4009 SE->getString())); 4010 } 4011 4012 // Copy the parameter declarations from the declarator D to the function 4013 // declaration NewFD, if they are available. First scavenge them into Params. 4014 llvm::SmallVector<ParmVarDecl*, 16> Params; 4015 if (D.isFunctionDeclarator()) { 4016 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 4017 4018 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 4019 // function that takes no arguments, not a function that takes a 4020 // single void argument. 4021 // We let through "const void" here because Sema::GetTypeForDeclarator 4022 // already checks for that case. 4023 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4024 FTI.ArgInfo[0].Param && 4025 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 4026 // Empty arg list, don't push any params. 4027 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 4028 4029 // In C++, the empty parameter-type-list must be spelled "void"; a 4030 // typedef of void is not permitted. 4031 if (getLangOptions().CPlusPlus && 4032 Param->getType().getUnqualifiedType() != Context.VoidTy) 4033 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 4034 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 4035 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 4036 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 4037 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 4038 Param->setDeclContext(NewFD); 4039 Params.push_back(Param); 4040 4041 if (Param->isInvalidDecl()) 4042 NewFD->setInvalidDecl(); 4043 } 4044 } 4045 4046 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 4047 // When we're declaring a function with a typedef, typeof, etc as in the 4048 // following example, we'll need to synthesize (unnamed) 4049 // parameters for use in the declaration. 4050 // 4051 // @code 4052 // typedef void fn(int); 4053 // fn f; 4054 // @endcode 4055 4056 // Synthesize a parameter for each argument type. 4057 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 4058 AE = FT->arg_type_end(); AI != AE; ++AI) { 4059 ParmVarDecl *Param = 4060 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 4061 Params.push_back(Param); 4062 } 4063 } else { 4064 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 4065 "Should not need args for typedef of non-prototype fn"); 4066 } 4067 // Finally, we know we have the right number of parameters, install them. 4068 NewFD->setParams(Params.data(), Params.size()); 4069 4070 // Process the non-inheritable attributes on this declaration. 4071 ProcessDeclAttributes(S, NewFD, D, 4072 /*NonInheritable=*/true, /*Inheritable=*/false); 4073 4074 if (!getLangOptions().CPlusPlus) { 4075 // Perform semantic checking on the function declaration. 4076 bool isExplctSpecialization=false; 4077 CheckFunctionDeclaration(S, NewFD, Previous, isExplctSpecialization, 4078 Redeclaration); 4079 assert((NewFD->isInvalidDecl() || !Redeclaration || 4080 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4081 "previous declaration set still overloaded"); 4082 } else { 4083 // If the declarator is a template-id, translate the parser's template 4084 // argument list into our AST format. 4085 bool HasExplicitTemplateArgs = false; 4086 TemplateArgumentListInfo TemplateArgs; 4087 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4088 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4089 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4090 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4091 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4092 TemplateId->getTemplateArgs(), 4093 TemplateId->NumArgs); 4094 translateTemplateArguments(TemplateArgsPtr, 4095 TemplateArgs); 4096 TemplateArgsPtr.release(); 4097 4098 HasExplicitTemplateArgs = true; 4099 4100 if (FunctionTemplate) { 4101 // Function template with explicit template arguments. 4102 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4103 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4104 4105 HasExplicitTemplateArgs = false; 4106 } else if (!isFunctionTemplateSpecialization && 4107 !D.getDeclSpec().isFriendSpecified()) { 4108 // We have encountered something that the user meant to be a 4109 // specialization (because it has explicitly-specified template 4110 // arguments) but that was not introduced with a "template<>" (or had 4111 // too few of them). 4112 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4113 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4114 << FixItHint::CreateInsertion( 4115 D.getDeclSpec().getSourceRange().getBegin(), 4116 "template<> "); 4117 isFunctionTemplateSpecialization = true; 4118 } else { 4119 // "friend void foo<>(int);" is an implicit specialization decl. 4120 isFunctionTemplateSpecialization = true; 4121 } 4122 } else if (isFriend && isFunctionTemplateSpecialization) { 4123 // This combination is only possible in a recovery case; the user 4124 // wrote something like: 4125 // template <> friend void foo(int); 4126 // which we're recovering from as if the user had written: 4127 // friend void foo<>(int); 4128 // Go ahead and fake up a template id. 4129 HasExplicitTemplateArgs = true; 4130 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4131 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4132 } 4133 4134 // If it's a friend (and only if it's a friend), it's possible 4135 // that either the specialized function type or the specialized 4136 // template is dependent, and therefore matching will fail. In 4137 // this case, don't check the specialization yet. 4138 if (isFunctionTemplateSpecialization && isFriend && 4139 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4140 assert(HasExplicitTemplateArgs && 4141 "friend function specialization without template args"); 4142 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4143 Previous)) 4144 NewFD->setInvalidDecl(); 4145 } else if (isFunctionTemplateSpecialization) { 4146 if (CurContext->isDependentContext() && CurContext->isRecord() 4147 && !isFriend) { 4148 Diag(NewFD->getLocation(), diag::err_function_specialization_in_class) 4149 << NewFD->getDeclName(); 4150 NewFD->setInvalidDecl(); 4151 return 0; 4152 } else if (CheckFunctionTemplateSpecialization(NewFD, 4153 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4154 Previous)) 4155 NewFD->setInvalidDecl(); 4156 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4157 if (CheckMemberSpecialization(NewFD, Previous)) 4158 NewFD->setInvalidDecl(); 4159 } 4160 4161 // Perform semantic checking on the function declaration. 4162 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4163 Redeclaration); 4164 4165 assert((NewFD->isInvalidDecl() || !Redeclaration || 4166 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4167 "previous declaration set still overloaded"); 4168 4169 NamedDecl *PrincipalDecl = (FunctionTemplate 4170 ? cast<NamedDecl>(FunctionTemplate) 4171 : NewFD); 4172 4173 if (isFriend && Redeclaration) { 4174 AccessSpecifier Access = AS_public; 4175 if (!NewFD->isInvalidDecl()) 4176 Access = NewFD->getPreviousDeclaration()->getAccess(); 4177 4178 NewFD->setAccess(Access); 4179 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4180 4181 PrincipalDecl->setObjectOfFriendDecl(true); 4182 } 4183 4184 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4185 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4186 PrincipalDecl->setNonMemberOperator(); 4187 4188 // If we have a function template, check the template parameter 4189 // list. This will check and merge default template arguments. 4190 if (FunctionTemplate) { 4191 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4192 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4193 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4194 D.getDeclSpec().isFriendSpecified() 4195 ? (IsFunctionDefinition 4196 ? TPC_FriendFunctionTemplateDefinition 4197 : TPC_FriendFunctionTemplate) 4198 : (D.getCXXScopeSpec().isSet() && 4199 DC && DC->isRecord() && 4200 DC->isDependentContext()) 4201 ? TPC_ClassTemplateMember 4202 : TPC_FunctionTemplate); 4203 } 4204 4205 if (NewFD->isInvalidDecl()) { 4206 // Ignore all the rest of this. 4207 } else if (!Redeclaration) { 4208 // Fake up an access specifier if it's supposed to be a class member. 4209 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4210 NewFD->setAccess(AS_public); 4211 4212 // Qualified decls generally require a previous declaration. 4213 if (D.getCXXScopeSpec().isSet()) { 4214 // ...with the major exception of templated-scope or 4215 // dependent-scope friend declarations. 4216 4217 // TODO: we currently also suppress this check in dependent 4218 // contexts because (1) the parameter depth will be off when 4219 // matching friend templates and (2) we might actually be 4220 // selecting a friend based on a dependent factor. But there 4221 // are situations where these conditions don't apply and we 4222 // can actually do this check immediately. 4223 if (isFriend && 4224 (TemplateParamLists.size() || 4225 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4226 CurContext->isDependentContext())) { 4227 // ignore these 4228 } else { 4229 // The user tried to provide an out-of-line definition for a 4230 // function that is a member of a class or namespace, but there 4231 // was no such member function declared (C++ [class.mfct]p2, 4232 // C++ [namespace.memdef]p2). For example: 4233 // 4234 // class X { 4235 // void f() const; 4236 // }; 4237 // 4238 // void X::f() { } // ill-formed 4239 // 4240 // Complain about this problem, and attempt to suggest close 4241 // matches (e.g., those that differ only in cv-qualifiers and 4242 // whether the parameter types are references). 4243 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4244 << Name << DC << D.getCXXScopeSpec().getRange(); 4245 NewFD->setInvalidDecl(); 4246 4247 DiagnoseInvalidRedeclaration(*this, NewFD); 4248 } 4249 4250 // Unqualified local friend declarations are required to resolve 4251 // to something. 4252 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4253 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4254 NewFD->setInvalidDecl(); 4255 DiagnoseInvalidRedeclaration(*this, NewFD); 4256 } 4257 4258 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4259 !isFriend && !isFunctionTemplateSpecialization && 4260 !isExplicitSpecialization) { 4261 // An out-of-line member function declaration must also be a 4262 // definition (C++ [dcl.meaning]p1). 4263 // Note that this is not the case for explicit specializations of 4264 // function templates or member functions of class templates, per 4265 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4266 // for compatibility with old SWIG code which likes to generate them. 4267 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4268 << D.getCXXScopeSpec().getRange(); 4269 } 4270 } 4271 4272 4273 // Handle attributes. We need to have merged decls when handling attributes 4274 // (for example to check for conflicts, etc). 4275 // FIXME: This needs to happen before we merge declarations. Then, 4276 // let attribute merging cope with attribute conflicts. 4277 ProcessDeclAttributes(S, NewFD, D, 4278 /*NonInheritable=*/false, /*Inheritable=*/true); 4279 4280 // attributes declared post-definition are currently ignored 4281 // FIXME: This should happen during attribute merging 4282 if (Redeclaration && Previous.isSingleResult()) { 4283 const FunctionDecl *Def; 4284 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4285 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 4286 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4287 Diag(Def->getLocation(), diag::note_previous_definition); 4288 } 4289 } 4290 4291 AddKnownFunctionAttributes(NewFD); 4292 4293 if (NewFD->hasAttr<OverloadableAttr>() && 4294 !NewFD->getType()->getAs<FunctionProtoType>()) { 4295 Diag(NewFD->getLocation(), 4296 diag::err_attribute_overloadable_no_prototype) 4297 << NewFD; 4298 4299 // Turn this into a variadic function with no parameters. 4300 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4301 FunctionProtoType::ExtProtoInfo EPI; 4302 EPI.Variadic = true; 4303 EPI.ExtInfo = FT->getExtInfo(); 4304 4305 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4306 NewFD->setType(R); 4307 } 4308 4309 // If there's a #pragma GCC visibility in scope, and this isn't a class 4310 // member, set the visibility of this function. 4311 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4312 AddPushedVisibilityAttribute(NewFD); 4313 4314 // If this is a locally-scoped extern C function, update the 4315 // map of such names. 4316 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4317 && !NewFD->isInvalidDecl()) 4318 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4319 4320 // Set this FunctionDecl's range up to the right paren. 4321 NewFD->setRangeEnd(D.getSourceRange().getEnd()); 4322 4323 if (getLangOptions().CPlusPlus) { 4324 if (FunctionTemplate) { 4325 if (NewFD->isInvalidDecl()) 4326 FunctionTemplate->setInvalidDecl(); 4327 return FunctionTemplate; 4328 } 4329 } 4330 4331 MarkUnusedFileScopedDecl(NewFD); 4332 4333 if (getLangOptions().CUDA) 4334 if (IdentifierInfo *II = NewFD->getIdentifier()) 4335 if (!NewFD->isInvalidDecl() && 4336 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4337 if (II->isStr("cudaConfigureCall")) { 4338 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4339 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4340 4341 Context.setcudaConfigureCallDecl(NewFD); 4342 } 4343 } 4344 4345 return NewFD; 4346} 4347 4348/// \brief Perform semantic checking of a new function declaration. 4349/// 4350/// Performs semantic analysis of the new function declaration 4351/// NewFD. This routine performs all semantic checking that does not 4352/// require the actual declarator involved in the declaration, and is 4353/// used both for the declaration of functions as they are parsed 4354/// (called via ActOnDeclarator) and for the declaration of functions 4355/// that have been instantiated via C++ template instantiation (called 4356/// via InstantiateDecl). 4357/// 4358/// \param IsExplicitSpecialiation whether this new function declaration is 4359/// an explicit specialization of the previous declaration. 4360/// 4361/// This sets NewFD->isInvalidDecl() to true if there was an error. 4362void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4363 LookupResult &Previous, 4364 bool IsExplicitSpecialization, 4365 bool &Redeclaration) { 4366 // If NewFD is already known erroneous, don't do any of this checking. 4367 if (NewFD->isInvalidDecl()) { 4368 // If this is a class member, mark the class invalid immediately. 4369 // This avoids some consistency errors later. 4370 if (isa<CXXMethodDecl>(NewFD)) 4371 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4372 4373 return; 4374 } 4375 4376 if (NewFD->getResultType()->isVariablyModifiedType()) { 4377 // Functions returning a variably modified type violate C99 6.7.5.2p2 4378 // because all functions have linkage. 4379 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4380 return NewFD->setInvalidDecl(); 4381 } 4382 4383 if (NewFD->isMain()) 4384 CheckMain(NewFD); 4385 4386 // Check for a previous declaration of this name. 4387 if (Previous.empty() && NewFD->isExternC()) { 4388 // Since we did not find anything by this name and we're declaring 4389 // an extern "C" function, look for a non-visible extern "C" 4390 // declaration with the same name. 4391 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4392 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4393 if (Pos != LocallyScopedExternalDecls.end()) 4394 Previous.addDecl(Pos->second); 4395 } 4396 4397 // Merge or overload the declaration with an existing declaration of 4398 // the same name, if appropriate. 4399 if (!Previous.empty()) { 4400 // Determine whether NewFD is an overload of PrevDecl or 4401 // a declaration that requires merging. If it's an overload, 4402 // there's no more work to do here; we'll just add the new 4403 // function to the scope. 4404 4405 NamedDecl *OldDecl = 0; 4406 if (!AllowOverloadingOfFunction(Previous, Context)) { 4407 Redeclaration = true; 4408 OldDecl = Previous.getFoundDecl(); 4409 } else { 4410 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4411 /*NewIsUsingDecl*/ false)) { 4412 case Ovl_Match: 4413 Redeclaration = true; 4414 break; 4415 4416 case Ovl_NonFunction: 4417 Redeclaration = true; 4418 break; 4419 4420 case Ovl_Overload: 4421 Redeclaration = false; 4422 break; 4423 } 4424 4425 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4426 // If a function name is overloadable in C, then every function 4427 // with that name must be marked "overloadable". 4428 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4429 << Redeclaration << NewFD; 4430 NamedDecl *OverloadedDecl = 0; 4431 if (Redeclaration) 4432 OverloadedDecl = OldDecl; 4433 else if (!Previous.empty()) 4434 OverloadedDecl = Previous.getRepresentativeDecl(); 4435 if (OverloadedDecl) 4436 Diag(OverloadedDecl->getLocation(), 4437 diag::note_attribute_overloadable_prev_overload); 4438 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4439 Context)); 4440 } 4441 } 4442 4443 if (Redeclaration) { 4444 // NewFD and OldDecl represent declarations that need to be 4445 // merged. 4446 if (MergeFunctionDecl(NewFD, OldDecl)) 4447 return NewFD->setInvalidDecl(); 4448 4449 Previous.clear(); 4450 Previous.addDecl(OldDecl); 4451 4452 if (FunctionTemplateDecl *OldTemplateDecl 4453 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4454 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4455 FunctionTemplateDecl *NewTemplateDecl 4456 = NewFD->getDescribedFunctionTemplate(); 4457 assert(NewTemplateDecl && "Template/non-template mismatch"); 4458 if (CXXMethodDecl *Method 4459 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4460 Method->setAccess(OldTemplateDecl->getAccess()); 4461 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4462 } 4463 4464 // If this is an explicit specialization of a member that is a function 4465 // template, mark it as a member specialization. 4466 if (IsExplicitSpecialization && 4467 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4468 NewTemplateDecl->setMemberSpecialization(); 4469 assert(OldTemplateDecl->isMemberSpecialization()); 4470 } 4471 } else { 4472 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4473 NewFD->setAccess(OldDecl->getAccess()); 4474 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4475 } 4476 } 4477 } 4478 4479 // Semantic checking for this function declaration (in isolation). 4480 if (getLangOptions().CPlusPlus) { 4481 // C++-specific checks. 4482 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4483 CheckConstructor(Constructor); 4484 } else if (CXXDestructorDecl *Destructor = 4485 dyn_cast<CXXDestructorDecl>(NewFD)) { 4486 CXXRecordDecl *Record = Destructor->getParent(); 4487 QualType ClassType = Context.getTypeDeclType(Record); 4488 4489 // FIXME: Shouldn't we be able to perform this check even when the class 4490 // type is dependent? Both gcc and edg can handle that. 4491 if (!ClassType->isDependentType()) { 4492 DeclarationName Name 4493 = Context.DeclarationNames.getCXXDestructorName( 4494 Context.getCanonicalType(ClassType)); 4495 if (NewFD->getDeclName() != Name) { 4496 Diag(NewFD->getLocation(), diag::err_destructor_name); 4497 return NewFD->setInvalidDecl(); 4498 } 4499 } 4500 } else if (CXXConversionDecl *Conversion 4501 = dyn_cast<CXXConversionDecl>(NewFD)) { 4502 ActOnConversionDeclarator(Conversion); 4503 } 4504 4505 // Find any virtual functions that this function overrides. 4506 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4507 if (!Method->isFunctionTemplateSpecialization() && 4508 !Method->getDescribedFunctionTemplate()) { 4509 if (AddOverriddenMethods(Method->getParent(), Method)) { 4510 // If the function was marked as "static", we have a problem. 4511 if (NewFD->getStorageClass() == SC_Static) { 4512 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4513 << NewFD->getDeclName(); 4514 for (CXXMethodDecl::method_iterator 4515 Overridden = Method->begin_overridden_methods(), 4516 OverriddenEnd = Method->end_overridden_methods(); 4517 Overridden != OverriddenEnd; 4518 ++Overridden) { 4519 Diag((*Overridden)->getLocation(), 4520 diag::note_overridden_virtual_function); 4521 } 4522 } 4523 } 4524 } 4525 } 4526 4527 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4528 if (NewFD->isOverloadedOperator() && 4529 CheckOverloadedOperatorDeclaration(NewFD)) 4530 return NewFD->setInvalidDecl(); 4531 4532 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4533 if (NewFD->getLiteralIdentifier() && 4534 CheckLiteralOperatorDeclaration(NewFD)) 4535 return NewFD->setInvalidDecl(); 4536 4537 // In C++, check default arguments now that we have merged decls. Unless 4538 // the lexical context is the class, because in this case this is done 4539 // during delayed parsing anyway. 4540 if (!CurContext->isRecord()) 4541 CheckCXXDefaultArguments(NewFD); 4542 4543 // If this function declares a builtin function, check the type of this 4544 // declaration against the expected type for the builtin. 4545 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 4546 ASTContext::GetBuiltinTypeError Error; 4547 QualType T = Context.GetBuiltinType(BuiltinID, Error); 4548 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 4549 // The type of this function differs from the type of the builtin, 4550 // so forget about the builtin entirely. 4551 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 4552 } 4553 } 4554 } 4555} 4556 4557void Sema::CheckMain(FunctionDecl* FD) { 4558 // C++ [basic.start.main]p3: A program that declares main to be inline 4559 // or static is ill-formed. 4560 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4561 // shall not appear in a declaration of main. 4562 // static main is not an error under C99, but we should warn about it. 4563 bool isInline = FD->isInlineSpecified(); 4564 bool isStatic = FD->getStorageClass() == SC_Static; 4565 if (isInline || isStatic) { 4566 unsigned diagID = diag::warn_unusual_main_decl; 4567 if (isInline || getLangOptions().CPlusPlus) 4568 diagID = diag::err_unusual_main_decl; 4569 4570 int which = isStatic + (isInline << 1) - 1; 4571 Diag(FD->getLocation(), diagID) << which; 4572 } 4573 4574 QualType T = FD->getType(); 4575 assert(T->isFunctionType() && "function decl is not of function type"); 4576 const FunctionType* FT = T->getAs<FunctionType>(); 4577 4578 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4579 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 4580 FD->setInvalidDecl(true); 4581 } 4582 4583 // Treat protoless main() as nullary. 4584 if (isa<FunctionNoProtoType>(FT)) return; 4585 4586 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4587 unsigned nparams = FTP->getNumArgs(); 4588 assert(FD->getNumParams() == nparams); 4589 4590 bool HasExtraParameters = (nparams > 3); 4591 4592 // Darwin passes an undocumented fourth argument of type char**. If 4593 // other platforms start sprouting these, the logic below will start 4594 // getting shifty. 4595 if (nparams == 4 && 4596 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4597 HasExtraParameters = false; 4598 4599 if (HasExtraParameters) { 4600 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4601 FD->setInvalidDecl(true); 4602 nparams = 3; 4603 } 4604 4605 // FIXME: a lot of the following diagnostics would be improved 4606 // if we had some location information about types. 4607 4608 QualType CharPP = 4609 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4610 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4611 4612 for (unsigned i = 0; i < nparams; ++i) { 4613 QualType AT = FTP->getArgType(i); 4614 4615 bool mismatch = true; 4616 4617 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4618 mismatch = false; 4619 else if (Expected[i] == CharPP) { 4620 // As an extension, the following forms are okay: 4621 // char const ** 4622 // char const * const * 4623 // char * const * 4624 4625 QualifierCollector qs; 4626 const PointerType* PT; 4627 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4628 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4629 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4630 qs.removeConst(); 4631 mismatch = !qs.empty(); 4632 } 4633 } 4634 4635 if (mismatch) { 4636 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4637 // TODO: suggest replacing given type with expected type 4638 FD->setInvalidDecl(true); 4639 } 4640 } 4641 4642 if (nparams == 1 && !FD->isInvalidDecl()) { 4643 Diag(FD->getLocation(), diag::warn_main_one_arg); 4644 } 4645 4646 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 4647 Diag(FD->getLocation(), diag::err_main_template_decl); 4648 FD->setInvalidDecl(); 4649 } 4650} 4651 4652bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4653 // FIXME: Need strict checking. In C89, we need to check for 4654 // any assignment, increment, decrement, function-calls, or 4655 // commas outside of a sizeof. In C99, it's the same list, 4656 // except that the aforementioned are allowed in unevaluated 4657 // expressions. Everything else falls under the 4658 // "may accept other forms of constant expressions" exception. 4659 // (We never end up here for C++, so the constant expression 4660 // rules there don't matter.) 4661 if (Init->isConstantInitializer(Context, false)) 4662 return false; 4663 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4664 << Init->getSourceRange(); 4665 return true; 4666} 4667 4668namespace { 4669 // Visits an initialization expression to see if OrigDecl is evaluated in 4670 // its own initialization and throws a warning if it does. 4671 class SelfReferenceChecker 4672 : public EvaluatedExprVisitor<SelfReferenceChecker> { 4673 Sema &S; 4674 Decl *OrigDecl; 4675 4676 public: 4677 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited; 4678 4679 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context), 4680 S(S), OrigDecl(OrigDecl) { } 4681 4682 void VisitExpr(Expr *E) { 4683 if (isa<ObjCMessageExpr>(*E)) return; 4684 Inherited::VisitExpr(E); 4685 } 4686 4687 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 4688 CheckForSelfReference(E); 4689 Inherited::VisitImplicitCastExpr(E); 4690 } 4691 4692 void CheckForSelfReference(ImplicitCastExpr *E) { 4693 if (E->getCastKind() != CK_LValueToRValue) return; 4694 Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts(); 4695 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr); 4696 if (!DRE) return; 4697 Decl* ReferenceDecl = DRE->getDecl(); 4698 if (OrigDecl != ReferenceDecl) return; 4699 LookupResult Result(S, DRE->getNameInfo(), Sema::LookupOrdinaryName, 4700 Sema::NotForRedeclaration); 4701 S.Diag(SubExpr->getLocStart(), diag::warn_uninit_self_reference_in_init) 4702 << Result.getLookupName() << OrigDecl->getLocation() 4703 << SubExpr->getSourceRange(); 4704 } 4705 }; 4706} 4707 4708/// AddInitializerToDecl - Adds the initializer Init to the 4709/// declaration dcl. If DirectInit is true, this is C++ direct 4710/// initialization rather than copy initialization. 4711void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 4712 bool DirectInit, bool TypeMayContainAuto) { 4713 // If there is no declaration, there was an error parsing it. Just ignore 4714 // the initializer. 4715 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 4716 return; 4717 4718 // Check for self-references within variable initializers. 4719 if (VarDecl *vd = dyn_cast<VarDecl>(RealDecl)) { 4720 // Variables declared within a function/method body are handled 4721 // by a dataflow analysis. 4722 if (!vd->hasLocalStorage() && !vd->isStaticLocal()) 4723 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 4724 } 4725 else { 4726 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 4727 } 4728 4729 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4730 // With declarators parsed the way they are, the parser cannot 4731 // distinguish between a normal initializer and a pure-specifier. 4732 // Thus this grotesque test. 4733 IntegerLiteral *IL; 4734 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4735 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4736 CheckPureMethod(Method, Init->getSourceRange()); 4737 else { 4738 Diag(Method->getLocation(), diag::err_member_function_initialization) 4739 << Method->getDeclName() << Init->getSourceRange(); 4740 Method->setInvalidDecl(); 4741 } 4742 return; 4743 } 4744 4745 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4746 if (!VDecl) { 4747 if (getLangOptions().CPlusPlus && 4748 RealDecl->getLexicalDeclContext()->isRecord() && 4749 isa<NamedDecl>(RealDecl)) 4750 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4751 else 4752 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4753 RealDecl->setInvalidDecl(); 4754 return; 4755 } 4756 4757 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 4758 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 4759 TypeSourceInfo *DeducedType = 0; 4760 if (!DeduceAutoType(VDecl->getTypeSourceInfo(), Init, DeducedType)) 4761 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 4762 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 4763 << Init->getSourceRange(); 4764 if (!DeducedType) { 4765 RealDecl->setInvalidDecl(); 4766 return; 4767 } 4768 VDecl->setTypeSourceInfo(DeducedType); 4769 VDecl->setType(DeducedType->getType()); 4770 4771 // If this is a redeclaration, check that the type we just deduced matches 4772 // the previously declared type. 4773 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 4774 MergeVarDeclTypes(VDecl, Old); 4775 } 4776 4777 4778 // A definition must end up with a complete type, which means it must be 4779 // complete with the restriction that an array type might be completed by the 4780 // initializer; note that later code assumes this restriction. 4781 QualType BaseDeclType = VDecl->getType(); 4782 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4783 BaseDeclType = Array->getElementType(); 4784 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4785 diag::err_typecheck_decl_incomplete_type)) { 4786 RealDecl->setInvalidDecl(); 4787 return; 4788 } 4789 4790 // The variable can not have an abstract class type. 4791 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4792 diag::err_abstract_type_in_decl, 4793 AbstractVariableType)) 4794 VDecl->setInvalidDecl(); 4795 4796 const VarDecl *Def; 4797 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4798 Diag(VDecl->getLocation(), diag::err_redefinition) 4799 << VDecl->getDeclName(); 4800 Diag(Def->getLocation(), diag::note_previous_definition); 4801 VDecl->setInvalidDecl(); 4802 return; 4803 } 4804 4805 const VarDecl* PrevInit = 0; 4806 if (getLangOptions().CPlusPlus) { 4807 // C++ [class.static.data]p4 4808 // If a static data member is of const integral or const 4809 // enumeration type, its declaration in the class definition can 4810 // specify a constant-initializer which shall be an integral 4811 // constant expression (5.19). In that case, the member can appear 4812 // in integral constant expressions. The member shall still be 4813 // defined in a namespace scope if it is used in the program and the 4814 // namespace scope definition shall not contain an initializer. 4815 // 4816 // We already performed a redefinition check above, but for static 4817 // data members we also need to check whether there was an in-class 4818 // declaration with an initializer. 4819 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4820 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4821 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4822 return; 4823 } 4824 4825 if (VDecl->hasLocalStorage()) 4826 getCurFunction()->setHasBranchProtectedScope(); 4827 4828 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 4829 VDecl->setInvalidDecl(); 4830 return; 4831 } 4832 } 4833 4834 // Capture the variable that is being initialized and the style of 4835 // initialization. 4836 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4837 4838 // FIXME: Poor source location information. 4839 InitializationKind Kind 4840 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4841 Init->getLocStart(), 4842 Init->getLocEnd()) 4843 : InitializationKind::CreateCopy(VDecl->getLocation(), 4844 Init->getLocStart()); 4845 4846 // Get the decls type and save a reference for later, since 4847 // CheckInitializerTypes may change it. 4848 QualType DclT = VDecl->getType(), SavT = DclT; 4849 if (VDecl->isLocalVarDecl()) { 4850 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4851 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4852 VDecl->setInvalidDecl(); 4853 } else if (!VDecl->isInvalidDecl()) { 4854 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4855 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4856 MultiExprArg(*this, &Init, 1), 4857 &DclT); 4858 if (Result.isInvalid()) { 4859 VDecl->setInvalidDecl(); 4860 return; 4861 } 4862 4863 Init = Result.takeAs<Expr>(); 4864 4865 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4866 // Don't check invalid declarations to avoid emitting useless diagnostics. 4867 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4868 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4869 CheckForConstantInitializer(Init, DclT); 4870 } 4871 } 4872 } else if (VDecl->isStaticDataMember() && 4873 VDecl->getLexicalDeclContext()->isRecord()) { 4874 // This is an in-class initialization for a static data member, e.g., 4875 // 4876 // struct S { 4877 // static const int value = 17; 4878 // }; 4879 4880 // Try to perform the initialization regardless. 4881 if (!VDecl->isInvalidDecl()) { 4882 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4883 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4884 MultiExprArg(*this, &Init, 1), 4885 &DclT); 4886 if (Result.isInvalid()) { 4887 VDecl->setInvalidDecl(); 4888 return; 4889 } 4890 4891 Init = Result.takeAs<Expr>(); 4892 } 4893 4894 // C++ [class.mem]p4: 4895 // A member-declarator can contain a constant-initializer only 4896 // if it declares a static member (9.4) of const integral or 4897 // const enumeration type, see 9.4.2. 4898 QualType T = VDecl->getType(); 4899 4900 // Do nothing on dependent types. 4901 if (T->isDependentType()) { 4902 4903 // Require constness. 4904 } else if (!T.isConstQualified()) { 4905 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4906 << Init->getSourceRange(); 4907 VDecl->setInvalidDecl(); 4908 4909 // We allow integer constant expressions in all cases. 4910 } else if (T->isIntegralOrEnumerationType()) { 4911 if (!Init->isValueDependent()) { 4912 // Check whether the expression is a constant expression. 4913 llvm::APSInt Value; 4914 SourceLocation Loc; 4915 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4916 Diag(Loc, diag::err_in_class_initializer_non_constant) 4917 << Init->getSourceRange(); 4918 VDecl->setInvalidDecl(); 4919 } 4920 } 4921 4922 // We allow floating-point constants as an extension in C++03, and 4923 // C++0x has far more complicated rules that we don't really 4924 // implement fully. 4925 } else { 4926 bool Allowed = false; 4927 if (getLangOptions().CPlusPlus0x) { 4928 Allowed = T->isLiteralType(); 4929 } else if (T->isFloatingType()) { // also permits complex, which is ok 4930 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4931 << T << Init->getSourceRange(); 4932 Allowed = true; 4933 } 4934 4935 if (!Allowed) { 4936 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4937 << T << Init->getSourceRange(); 4938 VDecl->setInvalidDecl(); 4939 4940 // TODO: there are probably expressions that pass here that shouldn't. 4941 } else if (!Init->isValueDependent() && 4942 !Init->isConstantInitializer(Context, false)) { 4943 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4944 << Init->getSourceRange(); 4945 VDecl->setInvalidDecl(); 4946 } 4947 } 4948 } else if (VDecl->isFileVarDecl()) { 4949 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4950 (!getLangOptions().CPlusPlus || 4951 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4952 Diag(VDecl->getLocation(), diag::warn_extern_init); 4953 if (!VDecl->isInvalidDecl()) { 4954 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4955 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4956 MultiExprArg(*this, &Init, 1), 4957 &DclT); 4958 if (Result.isInvalid()) { 4959 VDecl->setInvalidDecl(); 4960 return; 4961 } 4962 4963 Init = Result.takeAs<Expr>(); 4964 } 4965 4966 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4967 // Don't check invalid declarations to avoid emitting useless diagnostics. 4968 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4969 // C99 6.7.8p4. All file scoped initializers need to be constant. 4970 CheckForConstantInitializer(Init, DclT); 4971 } 4972 } 4973 // If the type changed, it means we had an incomplete type that was 4974 // completed by the initializer. For example: 4975 // int ary[] = { 1, 3, 5 }; 4976 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4977 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4978 VDecl->setType(DclT); 4979 Init->setType(DclT); 4980 } 4981 4982 4983 // If this variable is a local declaration with record type, make sure it 4984 // doesn't have a flexible member initialization. We only support this as a 4985 // global/static definition. 4986 if (VDecl->hasLocalStorage()) 4987 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4988 if (RT->getDecl()->hasFlexibleArrayMember()) { 4989 // Check whether the initializer tries to initialize the flexible 4990 // array member itself to anything other than an empty initializer list. 4991 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 4992 unsigned Index = std::distance(RT->getDecl()->field_begin(), 4993 RT->getDecl()->field_end()) - 1; 4994 if (Index < ILE->getNumInits() && 4995 !(isa<InitListExpr>(ILE->getInit(Index)) && 4996 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 4997 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4998 VDecl->setInvalidDecl(); 4999 } 5000 } 5001 } 5002 5003 // Check any implicit conversions within the expression. 5004 CheckImplicitConversions(Init, VDecl->getLocation()); 5005 5006 Init = MaybeCreateExprWithCleanups(Init); 5007 // Attach the initializer to the decl. 5008 VDecl->setInit(Init); 5009 5010 CheckCompleteVariableDeclaration(VDecl); 5011} 5012 5013/// ActOnInitializerError - Given that there was an error parsing an 5014/// initializer for the given declaration, try to return to some form 5015/// of sanity. 5016void Sema::ActOnInitializerError(Decl *D) { 5017 // Our main concern here is re-establishing invariants like "a 5018 // variable's type is either dependent or complete". 5019 if (!D || D->isInvalidDecl()) return; 5020 5021 VarDecl *VD = dyn_cast<VarDecl>(D); 5022 if (!VD) return; 5023 5024 // Auto types are meaningless if we can't make sense of the initializer. 5025 if (ParsingInitForAutoVars.count(D)) { 5026 D->setInvalidDecl(); 5027 return; 5028 } 5029 5030 QualType Ty = VD->getType(); 5031 if (Ty->isDependentType()) return; 5032 5033 // Require a complete type. 5034 if (RequireCompleteType(VD->getLocation(), 5035 Context.getBaseElementType(Ty), 5036 diag::err_typecheck_decl_incomplete_type)) { 5037 VD->setInvalidDecl(); 5038 return; 5039 } 5040 5041 // Require an abstract type. 5042 if (RequireNonAbstractType(VD->getLocation(), Ty, 5043 diag::err_abstract_type_in_decl, 5044 AbstractVariableType)) { 5045 VD->setInvalidDecl(); 5046 return; 5047 } 5048 5049 // Don't bother complaining about constructors or destructors, 5050 // though. 5051} 5052 5053void Sema::ActOnUninitializedDecl(Decl *RealDecl, 5054 bool TypeMayContainAuto) { 5055 // If there is no declaration, there was an error parsing it. Just ignore it. 5056 if (RealDecl == 0) 5057 return; 5058 5059 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 5060 QualType Type = Var->getType(); 5061 5062 // C++0x [dcl.spec.auto]p3 5063 if (TypeMayContainAuto && Type->getContainedAutoType()) { 5064 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 5065 << Var->getDeclName() << Type; 5066 Var->setInvalidDecl(); 5067 return; 5068 } 5069 5070 switch (Var->isThisDeclarationADefinition()) { 5071 case VarDecl::Definition: 5072 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 5073 break; 5074 5075 // We have an out-of-line definition of a static data member 5076 // that has an in-class initializer, so we type-check this like 5077 // a declaration. 5078 // 5079 // Fall through 5080 5081 case VarDecl::DeclarationOnly: 5082 // It's only a declaration. 5083 5084 // Block scope. C99 6.7p7: If an identifier for an object is 5085 // declared with no linkage (C99 6.2.2p6), the type for the 5086 // object shall be complete. 5087 if (!Type->isDependentType() && Var->isLocalVarDecl() && 5088 !Var->getLinkage() && !Var->isInvalidDecl() && 5089 RequireCompleteType(Var->getLocation(), Type, 5090 diag::err_typecheck_decl_incomplete_type)) 5091 Var->setInvalidDecl(); 5092 5093 // Make sure that the type is not abstract. 5094 if (!Type->isDependentType() && !Var->isInvalidDecl() && 5095 RequireNonAbstractType(Var->getLocation(), Type, 5096 diag::err_abstract_type_in_decl, 5097 AbstractVariableType)) 5098 Var->setInvalidDecl(); 5099 return; 5100 5101 case VarDecl::TentativeDefinition: 5102 // File scope. C99 6.9.2p2: A declaration of an identifier for an 5103 // object that has file scope without an initializer, and without a 5104 // storage-class specifier or with the storage-class specifier "static", 5105 // constitutes a tentative definition. Note: A tentative definition with 5106 // external linkage is valid (C99 6.2.2p5). 5107 if (!Var->isInvalidDecl()) { 5108 if (const IncompleteArrayType *ArrayT 5109 = Context.getAsIncompleteArrayType(Type)) { 5110 if (RequireCompleteType(Var->getLocation(), 5111 ArrayT->getElementType(), 5112 diag::err_illegal_decl_array_incomplete_type)) 5113 Var->setInvalidDecl(); 5114 } else if (Var->getStorageClass() == SC_Static) { 5115 // C99 6.9.2p3: If the declaration of an identifier for an object is 5116 // a tentative definition and has internal linkage (C99 6.2.2p3), the 5117 // declared type shall not be an incomplete type. 5118 // NOTE: code such as the following 5119 // static struct s; 5120 // struct s { int a; }; 5121 // is accepted by gcc. Hence here we issue a warning instead of 5122 // an error and we do not invalidate the static declaration. 5123 // NOTE: to avoid multiple warnings, only check the first declaration. 5124 if (Var->getPreviousDeclaration() == 0) 5125 RequireCompleteType(Var->getLocation(), Type, 5126 diag::ext_typecheck_decl_incomplete_type); 5127 } 5128 } 5129 5130 // Record the tentative definition; we're done. 5131 if (!Var->isInvalidDecl()) 5132 TentativeDefinitions.push_back(Var); 5133 return; 5134 } 5135 5136 // Provide a specific diagnostic for uninitialized variable 5137 // definitions with incomplete array type. 5138 if (Type->isIncompleteArrayType()) { 5139 Diag(Var->getLocation(), 5140 diag::err_typecheck_incomplete_array_needs_initializer); 5141 Var->setInvalidDecl(); 5142 return; 5143 } 5144 5145 // Provide a specific diagnostic for uninitialized variable 5146 // definitions with reference type. 5147 if (Type->isReferenceType()) { 5148 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5149 << Var->getDeclName() 5150 << SourceRange(Var->getLocation(), Var->getLocation()); 5151 Var->setInvalidDecl(); 5152 return; 5153 } 5154 5155 // Do not attempt to type-check the default initializer for a 5156 // variable with dependent type. 5157 if (Type->isDependentType()) 5158 return; 5159 5160 if (Var->isInvalidDecl()) 5161 return; 5162 5163 if (RequireCompleteType(Var->getLocation(), 5164 Context.getBaseElementType(Type), 5165 diag::err_typecheck_decl_incomplete_type)) { 5166 Var->setInvalidDecl(); 5167 return; 5168 } 5169 5170 // The variable can not have an abstract class type. 5171 if (RequireNonAbstractType(Var->getLocation(), Type, 5172 diag::err_abstract_type_in_decl, 5173 AbstractVariableType)) { 5174 Var->setInvalidDecl(); 5175 return; 5176 } 5177 5178 const RecordType *Record 5179 = Context.getBaseElementType(Type)->getAs<RecordType>(); 5180 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 5181 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 5182 // C++03 [dcl.init]p9: 5183 // If no initializer is specified for an object, and the 5184 // object is of (possibly cv-qualified) non-POD class type (or 5185 // array thereof), the object shall be default-initialized; if 5186 // the object is of const-qualified type, the underlying class 5187 // type shall have a user-declared default 5188 // constructor. Otherwise, if no initializer is specified for 5189 // a non- static object, the object and its subobjects, if 5190 // any, have an indeterminate initial value); if the object 5191 // or any of its subobjects are of const-qualified type, the 5192 // program is ill-formed. 5193 // FIXME: DPG thinks it is very fishy that C++0x disables this. 5194 } else { 5195 // Check for jumps past the implicit initializer. C++0x 5196 // clarifies that this applies to a "variable with automatic 5197 // storage duration", not a "local variable". 5198 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 5199 getCurFunction()->setHasBranchProtectedScope(); 5200 5201 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5202 InitializationKind Kind 5203 = InitializationKind::CreateDefault(Var->getLocation()); 5204 5205 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5206 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5207 MultiExprArg(*this, 0, 0)); 5208 if (Init.isInvalid()) 5209 Var->setInvalidDecl(); 5210 else if (Init.get()) 5211 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5212 } 5213 5214 CheckCompleteVariableDeclaration(Var); 5215 } 5216} 5217 5218void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5219 if (var->isInvalidDecl()) return; 5220 5221 // All the following checks are C++ only. 5222 if (!getLangOptions().CPlusPlus) return; 5223 5224 QualType baseType = Context.getBaseElementType(var->getType()); 5225 if (baseType->isDependentType()) return; 5226 5227 // __block variables might require us to capture a copy-initializer. 5228 if (var->hasAttr<BlocksAttr>()) { 5229 // It's currently invalid to ever have a __block variable with an 5230 // array type; should we diagnose that here? 5231 5232 // Regardless, we don't want to ignore array nesting when 5233 // constructing this copy. 5234 QualType type = var->getType(); 5235 5236 if (type->isStructureOrClassType()) { 5237 SourceLocation poi = var->getLocation(); 5238 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5239 ExprResult result = 5240 PerformCopyInitialization( 5241 InitializedEntity::InitializeBlock(poi, type, false), 5242 poi, Owned(varRef)); 5243 if (!result.isInvalid()) { 5244 result = MaybeCreateExprWithCleanups(result); 5245 Expr *init = result.takeAs<Expr>(); 5246 Context.setBlockVarCopyInits(var, init); 5247 } 5248 } 5249 } 5250 5251 // Check for global constructors. 5252 if (!var->getDeclContext()->isDependentContext() && 5253 var->hasGlobalStorage() && 5254 !var->isStaticLocal() && 5255 var->getInit() && 5256 !var->getInit()->isConstantInitializer(Context, 5257 baseType->isReferenceType())) 5258 Diag(var->getLocation(), diag::warn_global_constructor) 5259 << var->getInit()->getSourceRange(); 5260 5261 // Require the destructor. 5262 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5263 FinalizeVarWithDestructor(var, recordType); 5264} 5265 5266/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5267/// any semantic actions necessary after any initializer has been attached. 5268void 5269Sema::FinalizeDeclaration(Decl *ThisDecl) { 5270 // Note that we are no longer parsing the initializer for this declaration. 5271 ParsingInitForAutoVars.erase(ThisDecl); 5272} 5273 5274Sema::DeclGroupPtrTy 5275Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5276 Decl **Group, unsigned NumDecls) { 5277 llvm::SmallVector<Decl*, 8> Decls; 5278 5279 if (DS.isTypeSpecOwned()) 5280 Decls.push_back(DS.getRepAsDecl()); 5281 5282 for (unsigned i = 0; i != NumDecls; ++i) 5283 if (Decl *D = Group[i]) 5284 Decls.push_back(D); 5285 5286 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5287 DS.getTypeSpecType() == DeclSpec::TST_auto); 5288} 5289 5290/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5291/// group, performing any necessary semantic checking. 5292Sema::DeclGroupPtrTy 5293Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5294 bool TypeMayContainAuto) { 5295 // C++0x [dcl.spec.auto]p7: 5296 // If the type deduced for the template parameter U is not the same in each 5297 // deduction, the program is ill-formed. 5298 // FIXME: When initializer-list support is added, a distinction is needed 5299 // between the deduced type U and the deduced type which 'auto' stands for. 5300 // auto a = 0, b = { 1, 2, 3 }; 5301 // is legal because the deduced type U is 'int' in both cases. 5302 if (TypeMayContainAuto && NumDecls > 1) { 5303 QualType Deduced; 5304 CanQualType DeducedCanon; 5305 VarDecl *DeducedDecl = 0; 5306 for (unsigned i = 0; i != NumDecls; ++i) { 5307 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5308 AutoType *AT = D->getType()->getContainedAutoType(); 5309 // Don't reissue diagnostics when instantiating a template. 5310 if (AT && D->isInvalidDecl()) 5311 break; 5312 if (AT && AT->isDeduced()) { 5313 QualType U = AT->getDeducedType(); 5314 CanQualType UCanon = Context.getCanonicalType(U); 5315 if (Deduced.isNull()) { 5316 Deduced = U; 5317 DeducedCanon = UCanon; 5318 DeducedDecl = D; 5319 } else if (DeducedCanon != UCanon) { 5320 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5321 diag::err_auto_different_deductions) 5322 << Deduced << DeducedDecl->getDeclName() 5323 << U << D->getDeclName() 5324 << DeducedDecl->getInit()->getSourceRange() 5325 << D->getInit()->getSourceRange(); 5326 D->setInvalidDecl(); 5327 break; 5328 } 5329 } 5330 } 5331 } 5332 } 5333 5334 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5335} 5336 5337 5338/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5339/// to introduce parameters into function prototype scope. 5340Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5341 const DeclSpec &DS = D.getDeclSpec(); 5342 5343 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5344 VarDecl::StorageClass StorageClass = SC_None; 5345 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5346 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5347 StorageClass = SC_Register; 5348 StorageClassAsWritten = SC_Register; 5349 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5350 Diag(DS.getStorageClassSpecLoc(), 5351 diag::err_invalid_storage_class_in_func_decl); 5352 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5353 } 5354 5355 if (D.getDeclSpec().isThreadSpecified()) 5356 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5357 5358 DiagnoseFunctionSpecifiers(D); 5359 5360 TagDecl *OwnedDecl = 0; 5361 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 5362 QualType parmDeclType = TInfo->getType(); 5363 5364 if (getLangOptions().CPlusPlus) { 5365 // Check that there are no default arguments inside the type of this 5366 // parameter. 5367 CheckExtraCXXDefaultArguments(D); 5368 5369 if (OwnedDecl && OwnedDecl->isDefinition()) { 5370 // C++ [dcl.fct]p6: 5371 // Types shall not be defined in return or parameter types. 5372 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 5373 << Context.getTypeDeclType(OwnedDecl); 5374 } 5375 5376 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5377 if (D.getCXXScopeSpec().isSet()) { 5378 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5379 << D.getCXXScopeSpec().getRange(); 5380 D.getCXXScopeSpec().clear(); 5381 } 5382 } 5383 5384 // Ensure we have a valid name 5385 IdentifierInfo *II = 0; 5386 if (D.hasName()) { 5387 II = D.getIdentifier(); 5388 if (!II) { 5389 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5390 << GetNameForDeclarator(D).getName().getAsString(); 5391 D.setInvalidType(true); 5392 } 5393 } 5394 5395 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 5396 if (II) { 5397 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 5398 ForRedeclaration); 5399 LookupName(R, S); 5400 if (R.isSingleResult()) { 5401 NamedDecl *PrevDecl = R.getFoundDecl(); 5402 if (PrevDecl->isTemplateParameter()) { 5403 // Maybe we will complain about the shadowed template parameter. 5404 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5405 // Just pretend that we didn't see the previous declaration. 5406 PrevDecl = 0; 5407 } else if (S->isDeclScope(PrevDecl)) { 5408 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 5409 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5410 5411 // Recover by removing the name 5412 II = 0; 5413 D.SetIdentifier(0, D.getIdentifierLoc()); 5414 D.setInvalidType(true); 5415 } 5416 } 5417 } 5418 5419 // Temporarily put parameter variables in the translation unit, not 5420 // the enclosing context. This prevents them from accidentally 5421 // looking like class members in C++. 5422 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 5423 D.getSourceRange().getBegin(), 5424 D.getIdentifierLoc(), II, 5425 parmDeclType, TInfo, 5426 StorageClass, StorageClassAsWritten); 5427 5428 if (D.isInvalidType()) 5429 New->setInvalidDecl(); 5430 5431 // Add the parameter declaration into this scope. 5432 S->AddDecl(New); 5433 if (II) 5434 IdResolver.AddDecl(New); 5435 5436 ProcessDeclAttributes(S, New, D); 5437 5438 if (New->hasAttr<BlocksAttr>()) { 5439 Diag(New->getLocation(), diag::err_block_on_nonlocal); 5440 } 5441 return New; 5442} 5443 5444/// \brief Synthesizes a variable for a parameter arising from a 5445/// typedef. 5446ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 5447 SourceLocation Loc, 5448 QualType T) { 5449 /* FIXME: setting StartLoc == Loc. 5450 Would it be worth to modify callers so as to provide proper source 5451 location for the unnamed parameters, embedding the parameter's type? */ 5452 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, 5453 T, Context.getTrivialTypeSourceInfo(T, Loc), 5454 SC_None, SC_None, 0); 5455 Param->setImplicit(); 5456 return Param; 5457} 5458 5459void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 5460 ParmVarDecl * const *ParamEnd) { 5461 // Don't diagnose unused-parameter errors in template instantiations; we 5462 // will already have done so in the template itself. 5463 if (!ActiveTemplateInstantiations.empty()) 5464 return; 5465 5466 for (; Param != ParamEnd; ++Param) { 5467 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 5468 !(*Param)->hasAttr<UnusedAttr>()) { 5469 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 5470 << (*Param)->getDeclName(); 5471 } 5472 } 5473} 5474 5475void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 5476 ParmVarDecl * const *ParamEnd, 5477 QualType ReturnTy, 5478 NamedDecl *D) { 5479 if (LangOpts.NumLargeByValueCopy == 0) // No check. 5480 return; 5481 5482 // Warn if the return value is pass-by-value and larger than the specified 5483 // threshold. 5484 if (ReturnTy->isPODType()) { 5485 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 5486 if (Size > LangOpts.NumLargeByValueCopy) 5487 Diag(D->getLocation(), diag::warn_return_value_size) 5488 << D->getDeclName() << Size; 5489 } 5490 5491 // Warn if any parameter is pass-by-value and larger than the specified 5492 // threshold. 5493 for (; Param != ParamEnd; ++Param) { 5494 QualType T = (*Param)->getType(); 5495 if (!T->isPODType()) 5496 continue; 5497 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 5498 if (Size > LangOpts.NumLargeByValueCopy) 5499 Diag((*Param)->getLocation(), diag::warn_parameter_size) 5500 << (*Param)->getDeclName() << Size; 5501 } 5502} 5503 5504ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, 5505 SourceLocation NameLoc, IdentifierInfo *Name, 5506 QualType T, TypeSourceInfo *TSInfo, 5507 VarDecl::StorageClass StorageClass, 5508 VarDecl::StorageClass StorageClassAsWritten) { 5509 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, 5510 adjustParameterType(T), TSInfo, 5511 StorageClass, StorageClassAsWritten, 5512 0); 5513 5514 // Parameters can not be abstract class types. 5515 // For record types, this is done by the AbstractClassUsageDiagnoser once 5516 // the class has been completely parsed. 5517 if (!CurContext->isRecord() && 5518 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 5519 AbstractParamType)) 5520 New->setInvalidDecl(); 5521 5522 // Parameter declarators cannot be interface types. All ObjC objects are 5523 // passed by reference. 5524 if (T->isObjCObjectType()) { 5525 Diag(NameLoc, 5526 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 5527 New->setInvalidDecl(); 5528 } 5529 5530 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 5531 // duration shall not be qualified by an address-space qualifier." 5532 // Since all parameters have automatic store duration, they can not have 5533 // an address space. 5534 if (T.getAddressSpace() != 0) { 5535 Diag(NameLoc, diag::err_arg_with_address_space); 5536 New->setInvalidDecl(); 5537 } 5538 5539 return New; 5540} 5541 5542void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 5543 SourceLocation LocAfterDecls) { 5544 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 5545 5546 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 5547 // for a K&R function. 5548 if (!FTI.hasPrototype) { 5549 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 5550 --i; 5551 if (FTI.ArgInfo[i].Param == 0) { 5552 llvm::SmallString<256> Code; 5553 llvm::raw_svector_ostream(Code) << " int " 5554 << FTI.ArgInfo[i].Ident->getName() 5555 << ";\n"; 5556 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 5557 << FTI.ArgInfo[i].Ident 5558 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 5559 5560 // Implicitly declare the argument as type 'int' for lack of a better 5561 // type. 5562 AttributeFactory attrs; 5563 DeclSpec DS(attrs); 5564 const char* PrevSpec; // unused 5565 unsigned DiagID; // unused 5566 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 5567 PrevSpec, DiagID); 5568 Declarator ParamD(DS, Declarator::KNRTypeListContext); 5569 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 5570 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 5571 } 5572 } 5573 } 5574} 5575 5576Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 5577 Declarator &D) { 5578 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 5579 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 5580 Scope *ParentScope = FnBodyScope->getParent(); 5581 5582 Decl *DP = HandleDeclarator(ParentScope, D, 5583 MultiTemplateParamsArg(*this), 5584 /*IsFunctionDefinition=*/true); 5585 return ActOnStartOfFunctionDef(FnBodyScope, DP); 5586} 5587 5588static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 5589 // Don't warn about invalid declarations. 5590 if (FD->isInvalidDecl()) 5591 return false; 5592 5593 // Or declarations that aren't global. 5594 if (!FD->isGlobal()) 5595 return false; 5596 5597 // Don't warn about C++ member functions. 5598 if (isa<CXXMethodDecl>(FD)) 5599 return false; 5600 5601 // Don't warn about 'main'. 5602 if (FD->isMain()) 5603 return false; 5604 5605 // Don't warn about inline functions. 5606 if (FD->isInlined()) 5607 return false; 5608 5609 // Don't warn about function templates. 5610 if (FD->getDescribedFunctionTemplate()) 5611 return false; 5612 5613 // Don't warn about function template specializations. 5614 if (FD->isFunctionTemplateSpecialization()) 5615 return false; 5616 5617 bool MissingPrototype = true; 5618 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 5619 Prev; Prev = Prev->getPreviousDeclaration()) { 5620 // Ignore any declarations that occur in function or method 5621 // scope, because they aren't visible from the header. 5622 if (Prev->getDeclContext()->isFunctionOrMethod()) 5623 continue; 5624 5625 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 5626 break; 5627 } 5628 5629 return MissingPrototype; 5630} 5631 5632Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 5633 // Clear the last template instantiation error context. 5634 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 5635 5636 if (!D) 5637 return D; 5638 FunctionDecl *FD = 0; 5639 5640 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 5641 FD = FunTmpl->getTemplatedDecl(); 5642 else 5643 FD = cast<FunctionDecl>(D); 5644 5645 // Enter a new function scope 5646 PushFunctionScope(); 5647 5648 // See if this is a redefinition. 5649 // But don't complain if we're in GNU89 mode and the previous definition 5650 // was an extern inline function. 5651 const FunctionDecl *Definition; 5652 if (FD->hasBody(Definition) && 5653 !canRedefineFunction(Definition, getLangOptions())) { 5654 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 5655 Definition->getStorageClass() == SC_Extern) 5656 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 5657 << FD->getDeclName() << getLangOptions().CPlusPlus; 5658 else 5659 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 5660 Diag(Definition->getLocation(), diag::note_previous_definition); 5661 } 5662 5663 // Builtin functions cannot be defined. 5664 if (unsigned BuiltinID = FD->getBuiltinID()) { 5665 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 5666 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 5667 FD->setInvalidDecl(); 5668 } 5669 } 5670 5671 // The return type of a function definition must be complete 5672 // (C99 6.9.1p3, C++ [dcl.fct]p6). 5673 QualType ResultType = FD->getResultType(); 5674 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 5675 !FD->isInvalidDecl() && 5676 RequireCompleteType(FD->getLocation(), ResultType, 5677 diag::err_func_def_incomplete_result)) 5678 FD->setInvalidDecl(); 5679 5680 // GNU warning -Wmissing-prototypes: 5681 // Warn if a global function is defined without a previous 5682 // prototype declaration. This warning is issued even if the 5683 // definition itself provides a prototype. The aim is to detect 5684 // global functions that fail to be declared in header files. 5685 if (ShouldWarnAboutMissingPrototype(FD)) 5686 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 5687 5688 if (FnBodyScope) 5689 PushDeclContext(FnBodyScope, FD); 5690 5691 // Check the validity of our function parameters 5692 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 5693 /*CheckParameterNames=*/true); 5694 5695 // Introduce our parameters into the function scope 5696 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 5697 ParmVarDecl *Param = FD->getParamDecl(p); 5698 Param->setOwningFunction(FD); 5699 5700 // If this has an identifier, add it to the scope stack. 5701 if (Param->getIdentifier() && FnBodyScope) { 5702 CheckShadow(FnBodyScope, Param); 5703 5704 PushOnScopeChains(Param, FnBodyScope); 5705 } 5706 } 5707 5708 // Checking attributes of current function definition 5709 // dllimport attribute. 5710 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5711 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5712 // dllimport attribute cannot be directly applied to definition. 5713 // Microsoft accepts dllimport for functions defined within class scope. 5714 if (!DA->isInherited() && 5715 !(LangOpts.Microsoft && FD->getLexicalDeclContext()->isRecord())) { 5716 Diag(FD->getLocation(), 5717 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5718 << "dllimport"; 5719 FD->setInvalidDecl(); 5720 return FD; 5721 } 5722 5723 // Visual C++ appears to not think this is an issue, so only issue 5724 // a warning when Microsoft extensions are disabled. 5725 if (!LangOpts.Microsoft) { 5726 // If a symbol previously declared dllimport is later defined, the 5727 // attribute is ignored in subsequent references, and a warning is 5728 // emitted. 5729 Diag(FD->getLocation(), 5730 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5731 << FD->getName() << "dllimport"; 5732 } 5733 } 5734 return FD; 5735} 5736 5737/// \brief Given the set of return statements within a function body, 5738/// compute the variables that are subject to the named return value 5739/// optimization. 5740/// 5741/// Each of the variables that is subject to the named return value 5742/// optimization will be marked as NRVO variables in the AST, and any 5743/// return statement that has a marked NRVO variable as its NRVO candidate can 5744/// use the named return value optimization. 5745/// 5746/// This function applies a very simplistic algorithm for NRVO: if every return 5747/// statement in the function has the same NRVO candidate, that candidate is 5748/// the NRVO variable. 5749/// 5750/// FIXME: Employ a smarter algorithm that accounts for multiple return 5751/// statements and the lifetimes of the NRVO candidates. We should be able to 5752/// find a maximal set of NRVO variables. 5753static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5754 ReturnStmt **Returns = Scope->Returns.data(); 5755 5756 const VarDecl *NRVOCandidate = 0; 5757 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5758 if (!Returns[I]->getNRVOCandidate()) 5759 return; 5760 5761 if (!NRVOCandidate) 5762 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5763 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5764 return; 5765 } 5766 5767 if (NRVOCandidate) 5768 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5769} 5770 5771Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5772 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5773} 5774 5775Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5776 bool IsInstantiation) { 5777 FunctionDecl *FD = 0; 5778 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5779 if (FunTmpl) 5780 FD = FunTmpl->getTemplatedDecl(); 5781 else 5782 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5783 5784 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5785 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 5786 5787 if (FD) { 5788 FD->setBody(Body); 5789 if (FD->isMain()) { 5790 // C and C++ allow for main to automagically return 0. 5791 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5792 FD->setHasImplicitReturnZero(true); 5793 WP.disableCheckFallThrough(); 5794 } 5795 5796 if (!FD->isInvalidDecl()) { 5797 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5798 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 5799 FD->getResultType(), FD); 5800 5801 // If this is a constructor, we need a vtable. 5802 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5803 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5804 5805 ComputeNRVO(Body, getCurFunction()); 5806 } 5807 5808 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5809 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5810 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5811 MD->setBody(Body); 5812 if (Body) 5813 MD->setEndLoc(Body->getLocEnd()); 5814 if (!MD->isInvalidDecl()) { 5815 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5816 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 5817 MD->getResultType(), MD); 5818 } 5819 } else { 5820 return 0; 5821 } 5822 5823 // Verify and clean out per-function state. 5824 if (Body) { 5825 // C++ constructors that have function-try-blocks can't have return 5826 // statements in the handlers of that block. (C++ [except.handle]p14) 5827 // Verify this. 5828 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5829 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5830 5831 // Verify that that gotos and switch cases don't jump into scopes illegally. 5832 // Verify that that gotos and switch cases don't jump into scopes illegally. 5833 if (getCurFunction()->NeedsScopeChecking() && 5834 !dcl->isInvalidDecl() && 5835 !hasAnyErrorsInThisFunction()) 5836 DiagnoseInvalidJumps(Body); 5837 5838 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5839 if (!Destructor->getParent()->isDependentType()) 5840 CheckDestructor(Destructor); 5841 5842 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5843 Destructor->getParent()); 5844 } 5845 5846 // If any errors have occurred, clear out any temporaries that may have 5847 // been leftover. This ensures that these temporaries won't be picked up for 5848 // deletion in some later function. 5849 if (PP.getDiagnostics().hasErrorOccurred() || 5850 PP.getDiagnostics().getSuppressAllDiagnostics()) 5851 ExprTemporaries.clear(); 5852 else if (!isa<FunctionTemplateDecl>(dcl)) { 5853 // Since the body is valid, issue any analysis-based warnings that are 5854 // enabled. 5855 ActivePolicy = &WP; 5856 } 5857 5858 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5859 } 5860 5861 if (!IsInstantiation) 5862 PopDeclContext(); 5863 5864 PopFunctionOrBlockScope(ActivePolicy, dcl); 5865 5866 // If any errors have occurred, clear out any temporaries that may have 5867 // been leftover. This ensures that these temporaries won't be picked up for 5868 // deletion in some later function. 5869 if (getDiagnostics().hasErrorOccurred()) 5870 ExprTemporaries.clear(); 5871 5872 return dcl; 5873} 5874 5875/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5876/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5877NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5878 IdentifierInfo &II, Scope *S) { 5879 // Before we produce a declaration for an implicitly defined 5880 // function, see whether there was a locally-scoped declaration of 5881 // this name as a function or variable. If so, use that 5882 // (non-visible) declaration, and complain about it. 5883 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5884 = LocallyScopedExternalDecls.find(&II); 5885 if (Pos != LocallyScopedExternalDecls.end()) { 5886 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5887 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5888 return Pos->second; 5889 } 5890 5891 // Extension in C99. Legal in C90, but warn about it. 5892 if (II.getName().startswith("__builtin_")) 5893 Diag(Loc, diag::warn_builtin_unknown) << &II; 5894 else if (getLangOptions().C99) 5895 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5896 else 5897 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5898 5899 // Set a Declarator for the implicit definition: int foo(); 5900 const char *Dummy; 5901 AttributeFactory attrFactory; 5902 DeclSpec DS(attrFactory); 5903 unsigned DiagID; 5904 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5905 (void)Error; // Silence warning. 5906 assert(!Error && "Error setting up implicit decl!"); 5907 Declarator D(DS, Declarator::BlockContext); 5908 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5909 0, 0, true, SourceLocation(), 5910 EST_None, SourceLocation(), 5911 0, 0, 0, 0, Loc, Loc, D), 5912 DS.getAttributes(), 5913 SourceLocation()); 5914 D.SetIdentifier(&II, Loc); 5915 5916 // Insert this function into translation-unit scope. 5917 5918 DeclContext *PrevDC = CurContext; 5919 CurContext = Context.getTranslationUnitDecl(); 5920 5921 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5922 FD->setImplicit(); 5923 5924 CurContext = PrevDC; 5925 5926 AddKnownFunctionAttributes(FD); 5927 5928 return FD; 5929} 5930 5931/// \brief Adds any function attributes that we know a priori based on 5932/// the declaration of this function. 5933/// 5934/// These attributes can apply both to implicitly-declared builtins 5935/// (like __builtin___printf_chk) or to library-declared functions 5936/// like NSLog or printf. 5937void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5938 if (FD->isInvalidDecl()) 5939 return; 5940 5941 // If this is a built-in function, map its builtin attributes to 5942 // actual attributes. 5943 if (unsigned BuiltinID = FD->getBuiltinID()) { 5944 // Handle printf-formatting attributes. 5945 unsigned FormatIdx; 5946 bool HasVAListArg; 5947 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5948 if (!FD->getAttr<FormatAttr>()) 5949 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5950 "printf", FormatIdx+1, 5951 HasVAListArg ? 0 : FormatIdx+2)); 5952 } 5953 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5954 HasVAListArg)) { 5955 if (!FD->getAttr<FormatAttr>()) 5956 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5957 "scanf", FormatIdx+1, 5958 HasVAListArg ? 0 : FormatIdx+2)); 5959 } 5960 5961 // Mark const if we don't care about errno and that is the only 5962 // thing preventing the function from being const. This allows 5963 // IRgen to use LLVM intrinsics for such functions. 5964 if (!getLangOptions().MathErrno && 5965 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5966 if (!FD->getAttr<ConstAttr>()) 5967 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5968 } 5969 5970 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5971 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5972 if (Context.BuiltinInfo.isConst(BuiltinID)) 5973 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5974 } 5975 5976 IdentifierInfo *Name = FD->getIdentifier(); 5977 if (!Name) 5978 return; 5979 if ((!getLangOptions().CPlusPlus && 5980 FD->getDeclContext()->isTranslationUnit()) || 5981 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5982 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5983 LinkageSpecDecl::lang_c)) { 5984 // Okay: this could be a libc/libm/Objective-C function we know 5985 // about. 5986 } else 5987 return; 5988 5989 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5990 // FIXME: NSLog and NSLogv should be target specific 5991 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5992 // FIXME: We known better than our headers. 5993 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5994 } else 5995 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5996 "printf", 1, 5997 Name->isStr("NSLogv") ? 0 : 2)); 5998 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5999 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 6000 // target-specific builtins, perhaps? 6001 if (!FD->getAttr<FormatAttr>()) 6002 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6003 "printf", 2, 6004 Name->isStr("vasprintf") ? 0 : 3)); 6005 } 6006} 6007 6008TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 6009 TypeSourceInfo *TInfo) { 6010 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 6011 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 6012 6013 if (!TInfo) { 6014 assert(D.isInvalidType() && "no declarator info for valid type"); 6015 TInfo = Context.getTrivialTypeSourceInfo(T); 6016 } 6017 6018 // Scope manipulation handled by caller. 6019 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 6020 D.getSourceRange().getBegin(), 6021 D.getIdentifierLoc(), 6022 D.getIdentifier(), 6023 TInfo); 6024 6025 // Bail out immediately if we have an invalid declaration. 6026 if (D.isInvalidType()) { 6027 NewTD->setInvalidDecl(); 6028 return NewTD; 6029 } 6030 6031 // C++ [dcl.typedef]p8: 6032 // If the typedef declaration defines an unnamed class (or 6033 // enum), the first typedef-name declared by the declaration 6034 // to be that class type (or enum type) is used to denote the 6035 // class type (or enum type) for linkage purposes only. 6036 // We need to check whether the type was declared in the declaration. 6037 switch (D.getDeclSpec().getTypeSpecType()) { 6038 case TST_enum: 6039 case TST_struct: 6040 case TST_union: 6041 case TST_class: { 6042 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 6043 6044 // Do nothing if the tag is not anonymous or already has an 6045 // associated typedef (from an earlier typedef in this decl group). 6046 if (tagFromDeclSpec->getIdentifier()) break; 6047 if (tagFromDeclSpec->getTypedefForAnonDecl()) break; 6048 6049 // A well-formed anonymous tag must always be a TUK_Definition. 6050 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 6051 6052 // The type must match the tag exactly; no qualifiers allowed. 6053 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 6054 break; 6055 6056 // Otherwise, set this is the anon-decl typedef for the tag. 6057 tagFromDeclSpec->setTypedefForAnonDecl(NewTD); 6058 break; 6059 } 6060 6061 default: 6062 break; 6063 } 6064 6065 return NewTD; 6066} 6067 6068 6069/// \brief Determine whether a tag with a given kind is acceptable 6070/// as a redeclaration of the given tag declaration. 6071/// 6072/// \returns true if the new tag kind is acceptable, false otherwise. 6073bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 6074 TagTypeKind NewTag, 6075 SourceLocation NewTagLoc, 6076 const IdentifierInfo &Name) { 6077 // C++ [dcl.type.elab]p3: 6078 // The class-key or enum keyword present in the 6079 // elaborated-type-specifier shall agree in kind with the 6080 // declaration to which the name in the elaborated-type-specifier 6081 // refers. This rule also applies to the form of 6082 // elaborated-type-specifier that declares a class-name or 6083 // friend class since it can be construed as referring to the 6084 // definition of the class. Thus, in any 6085 // elaborated-type-specifier, the enum keyword shall be used to 6086 // refer to an enumeration (7.2), the union class-key shall be 6087 // used to refer to a union (clause 9), and either the class or 6088 // struct class-key shall be used to refer to a class (clause 9) 6089 // declared using the class or struct class-key. 6090 TagTypeKind OldTag = Previous->getTagKind(); 6091 if (OldTag == NewTag) 6092 return true; 6093 6094 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 6095 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 6096 // Warn about the struct/class tag mismatch. 6097 bool isTemplate = false; 6098 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 6099 isTemplate = Record->getDescribedClassTemplate(); 6100 6101 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6102 << (NewTag == TTK_Class) 6103 << isTemplate << &Name 6104 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 6105 OldTag == TTK_Class? "class" : "struct"); 6106 Diag(Previous->getLocation(), diag::note_previous_use); 6107 return true; 6108 } 6109 return false; 6110} 6111 6112/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 6113/// former case, Name will be non-null. In the later case, Name will be null. 6114/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 6115/// reference/declaration/definition of a tag. 6116Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 6117 SourceLocation KWLoc, CXXScopeSpec &SS, 6118 IdentifierInfo *Name, SourceLocation NameLoc, 6119 AttributeList *Attr, AccessSpecifier AS, 6120 MultiTemplateParamsArg TemplateParameterLists, 6121 bool &OwnedDecl, bool &IsDependent, 6122 bool ScopedEnum, bool ScopedEnumUsesClassTag, 6123 TypeResult UnderlyingType) { 6124 // If this is not a definition, it must have a name. 6125 assert((Name != 0 || TUK == TUK_Definition) && 6126 "Nameless record must be a definition!"); 6127 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 6128 6129 OwnedDecl = false; 6130 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 6131 6132 // FIXME: Check explicit specializations more carefully. 6133 bool isExplicitSpecialization = false; 6134 bool Invalid = false; 6135 6136 // We only need to do this matching if we have template parameters 6137 // or a scope specifier, which also conveniently avoids this work 6138 // for non-C++ cases. 6139 if (TemplateParameterLists.size() > 0 || 6140 (SS.isNotEmpty() && TUK != TUK_Reference)) { 6141 if (TemplateParameterList *TemplateParams 6142 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 6143 TemplateParameterLists.get(), 6144 TemplateParameterLists.size(), 6145 TUK == TUK_Friend, 6146 isExplicitSpecialization, 6147 Invalid)) { 6148 if (TemplateParams->size() > 0) { 6149 // This is a declaration or definition of a class template (which may 6150 // be a member of another template). 6151 6152 if (Invalid) 6153 return 0; 6154 6155 OwnedDecl = false; 6156 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6157 SS, Name, NameLoc, Attr, 6158 TemplateParams, AS, 6159 TemplateParameterLists.size() - 1, 6160 (TemplateParameterList**) TemplateParameterLists.release()); 6161 return Result.get(); 6162 } else { 6163 // The "template<>" header is extraneous. 6164 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6165 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6166 isExplicitSpecialization = true; 6167 } 6168 } 6169 } 6170 6171 // Figure out the underlying type if this a enum declaration. We need to do 6172 // this early, because it's needed to detect if this is an incompatible 6173 // redeclaration. 6174 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6175 6176 if (Kind == TTK_Enum) { 6177 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6178 // No underlying type explicitly specified, or we failed to parse the 6179 // type, default to int. 6180 EnumUnderlying = Context.IntTy.getTypePtr(); 6181 else if (UnderlyingType.get()) { 6182 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6183 // integral type; any cv-qualification is ignored. 6184 TypeSourceInfo *TI = 0; 6185 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6186 EnumUnderlying = TI; 6187 6188 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6189 6190 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6191 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6192 << T; 6193 // Recover by falling back to int. 6194 EnumUnderlying = Context.IntTy.getTypePtr(); 6195 } 6196 6197 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6198 UPPC_FixedUnderlyingType)) 6199 EnumUnderlying = Context.IntTy.getTypePtr(); 6200 6201 } else if (getLangOptions().Microsoft) 6202 // Microsoft enums are always of int type. 6203 EnumUnderlying = Context.IntTy.getTypePtr(); 6204 } 6205 6206 DeclContext *SearchDC = CurContext; 6207 DeclContext *DC = CurContext; 6208 bool isStdBadAlloc = false; 6209 6210 RedeclarationKind Redecl = ForRedeclaration; 6211 if (TUK == TUK_Friend || TUK == TUK_Reference) 6212 Redecl = NotForRedeclaration; 6213 6214 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6215 6216 if (Name && SS.isNotEmpty()) { 6217 // We have a nested-name tag ('struct foo::bar'). 6218 6219 // Check for invalid 'foo::'. 6220 if (SS.isInvalid()) { 6221 Name = 0; 6222 goto CreateNewDecl; 6223 } 6224 6225 // If this is a friend or a reference to a class in a dependent 6226 // context, don't try to make a decl for it. 6227 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6228 DC = computeDeclContext(SS, false); 6229 if (!DC) { 6230 IsDependent = true; 6231 return 0; 6232 } 6233 } else { 6234 DC = computeDeclContext(SS, true); 6235 if (!DC) { 6236 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6237 << SS.getRange(); 6238 return 0; 6239 } 6240 } 6241 6242 if (RequireCompleteDeclContext(SS, DC)) 6243 return 0; 6244 6245 SearchDC = DC; 6246 // Look-up name inside 'foo::'. 6247 LookupQualifiedName(Previous, DC); 6248 6249 if (Previous.isAmbiguous()) 6250 return 0; 6251 6252 if (Previous.empty()) { 6253 // Name lookup did not find anything. However, if the 6254 // nested-name-specifier refers to the current instantiation, 6255 // and that current instantiation has any dependent base 6256 // classes, we might find something at instantiation time: treat 6257 // this as a dependent elaborated-type-specifier. 6258 // But this only makes any sense for reference-like lookups. 6259 if (Previous.wasNotFoundInCurrentInstantiation() && 6260 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6261 IsDependent = true; 6262 return 0; 6263 } 6264 6265 // A tag 'foo::bar' must already exist. 6266 Diag(NameLoc, diag::err_not_tag_in_scope) 6267 << Kind << Name << DC << SS.getRange(); 6268 Name = 0; 6269 Invalid = true; 6270 goto CreateNewDecl; 6271 } 6272 } else if (Name) { 6273 // If this is a named struct, check to see if there was a previous forward 6274 // declaration or definition. 6275 // FIXME: We're looking into outer scopes here, even when we 6276 // shouldn't be. Doing so can result in ambiguities that we 6277 // shouldn't be diagnosing. 6278 LookupName(Previous, S); 6279 6280 // Note: there used to be some attempt at recovery here. 6281 if (Previous.isAmbiguous()) 6282 return 0; 6283 6284 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6285 // FIXME: This makes sure that we ignore the contexts associated 6286 // with C structs, unions, and enums when looking for a matching 6287 // tag declaration or definition. See the similar lookup tweak 6288 // in Sema::LookupName; is there a better way to deal with this? 6289 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 6290 SearchDC = SearchDC->getParent(); 6291 } 6292 } else if (S->isFunctionPrototypeScope()) { 6293 // If this is an enum declaration in function prototype scope, set its 6294 // initial context to the translation unit. 6295 SearchDC = Context.getTranslationUnitDecl(); 6296 } 6297 6298 if (Previous.isSingleResult() && 6299 Previous.getFoundDecl()->isTemplateParameter()) { 6300 // Maybe we will complain about the shadowed template parameter. 6301 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 6302 // Just pretend that we didn't see the previous declaration. 6303 Previous.clear(); 6304 } 6305 6306 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 6307 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 6308 // This is a declaration of or a reference to "std::bad_alloc". 6309 isStdBadAlloc = true; 6310 6311 if (Previous.empty() && StdBadAlloc) { 6312 // std::bad_alloc has been implicitly declared (but made invisible to 6313 // name lookup). Fill in this implicit declaration as the previous 6314 // declaration, so that the declarations get chained appropriately. 6315 Previous.addDecl(getStdBadAlloc()); 6316 } 6317 } 6318 6319 // If we didn't find a previous declaration, and this is a reference 6320 // (or friend reference), move to the correct scope. In C++, we 6321 // also need to do a redeclaration lookup there, just in case 6322 // there's a shadow friend decl. 6323 if (Name && Previous.empty() && 6324 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6325 if (Invalid) goto CreateNewDecl; 6326 assert(SS.isEmpty()); 6327 6328 if (TUK == TUK_Reference) { 6329 // C++ [basic.scope.pdecl]p5: 6330 // -- for an elaborated-type-specifier of the form 6331 // 6332 // class-key identifier 6333 // 6334 // if the elaborated-type-specifier is used in the 6335 // decl-specifier-seq or parameter-declaration-clause of a 6336 // function defined in namespace scope, the identifier is 6337 // declared as a class-name in the namespace that contains 6338 // the declaration; otherwise, except as a friend 6339 // declaration, the identifier is declared in the smallest 6340 // non-class, non-function-prototype scope that contains the 6341 // declaration. 6342 // 6343 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 6344 // C structs and unions. 6345 // 6346 // It is an error in C++ to declare (rather than define) an enum 6347 // type, including via an elaborated type specifier. We'll 6348 // diagnose that later; for now, declare the enum in the same 6349 // scope as we would have picked for any other tag type. 6350 // 6351 // GNU C also supports this behavior as part of its incomplete 6352 // enum types extension, while GNU C++ does not. 6353 // 6354 // Find the context where we'll be declaring the tag. 6355 // FIXME: We would like to maintain the current DeclContext as the 6356 // lexical context, 6357 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 6358 SearchDC = SearchDC->getParent(); 6359 6360 // Find the scope where we'll be declaring the tag. 6361 while (S->isClassScope() || 6362 (getLangOptions().CPlusPlus && 6363 S->isFunctionPrototypeScope()) || 6364 ((S->getFlags() & Scope::DeclScope) == 0) || 6365 (S->getEntity() && 6366 ((DeclContext *)S->getEntity())->isTransparentContext())) 6367 S = S->getParent(); 6368 } else { 6369 assert(TUK == TUK_Friend); 6370 // C++ [namespace.memdef]p3: 6371 // If a friend declaration in a non-local class first declares a 6372 // class or function, the friend class or function is a member of 6373 // the innermost enclosing namespace. 6374 SearchDC = SearchDC->getEnclosingNamespaceContext(); 6375 } 6376 6377 // In C++, we need to do a redeclaration lookup to properly 6378 // diagnose some problems. 6379 if (getLangOptions().CPlusPlus) { 6380 Previous.setRedeclarationKind(ForRedeclaration); 6381 LookupQualifiedName(Previous, SearchDC); 6382 } 6383 } 6384 6385 if (!Previous.empty()) { 6386 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 6387 6388 // It's okay to have a tag decl in the same scope as a typedef 6389 // which hides a tag decl in the same scope. Finding this 6390 // insanity with a redeclaration lookup can only actually happen 6391 // in C++. 6392 // 6393 // This is also okay for elaborated-type-specifiers, which is 6394 // technically forbidden by the current standard but which is 6395 // okay according to the likely resolution of an open issue; 6396 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 6397 if (getLangOptions().CPlusPlus) { 6398 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 6399 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 6400 TagDecl *Tag = TT->getDecl(); 6401 if (Tag->getDeclName() == Name && 6402 Tag->getDeclContext()->getRedeclContext() 6403 ->Equals(TD->getDeclContext()->getRedeclContext())) { 6404 PrevDecl = Tag; 6405 Previous.clear(); 6406 Previous.addDecl(Tag); 6407 Previous.resolveKind(); 6408 } 6409 } 6410 } 6411 } 6412 6413 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 6414 // If this is a use of a previous tag, or if the tag is already declared 6415 // in the same scope (so that the definition/declaration completes or 6416 // rementions the tag), reuse the decl. 6417 if (TUK == TUK_Reference || TUK == TUK_Friend || 6418 isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { 6419 // Make sure that this wasn't declared as an enum and now used as a 6420 // struct or something similar. 6421 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 6422 bool SafeToContinue 6423 = (PrevTagDecl->getTagKind() != TTK_Enum && 6424 Kind != TTK_Enum); 6425 if (SafeToContinue) 6426 Diag(KWLoc, diag::err_use_with_wrong_tag) 6427 << Name 6428 << FixItHint::CreateReplacement(SourceRange(KWLoc), 6429 PrevTagDecl->getKindName()); 6430 else 6431 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 6432 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6433 6434 if (SafeToContinue) 6435 Kind = PrevTagDecl->getTagKind(); 6436 else { 6437 // Recover by making this an anonymous redefinition. 6438 Name = 0; 6439 Previous.clear(); 6440 Invalid = true; 6441 } 6442 } 6443 6444 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 6445 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 6446 6447 // All conflicts with previous declarations are recovered by 6448 // returning the previous declaration. 6449 if (ScopedEnum != PrevEnum->isScoped()) { 6450 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 6451 << PrevEnum->isScoped(); 6452 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6453 return PrevTagDecl; 6454 } 6455 else if (EnumUnderlying && PrevEnum->isFixed()) { 6456 QualType T; 6457 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6458 T = TI->getType(); 6459 else 6460 T = QualType(EnumUnderlying.get<const Type*>(), 0); 6461 6462 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 6463 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 6464 diag::err_enum_redeclare_type_mismatch) 6465 << T 6466 << PrevEnum->getIntegerType(); 6467 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6468 return PrevTagDecl; 6469 } 6470 } 6471 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 6472 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 6473 << PrevEnum->isFixed(); 6474 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6475 return PrevTagDecl; 6476 } 6477 } 6478 6479 if (!Invalid) { 6480 // If this is a use, just return the declaration we found. 6481 6482 // FIXME: In the future, return a variant or some other clue 6483 // for the consumer of this Decl to know it doesn't own it. 6484 // For our current ASTs this shouldn't be a problem, but will 6485 // need to be changed with DeclGroups. 6486 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 6487 TUK == TUK_Friend) 6488 return PrevTagDecl; 6489 6490 // Diagnose attempts to redefine a tag. 6491 if (TUK == TUK_Definition) { 6492 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 6493 // If we're defining a specialization and the previous definition 6494 // is from an implicit instantiation, don't emit an error 6495 // here; we'll catch this in the general case below. 6496 if (!isExplicitSpecialization || 6497 !isa<CXXRecordDecl>(Def) || 6498 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 6499 == TSK_ExplicitSpecialization) { 6500 Diag(NameLoc, diag::err_redefinition) << Name; 6501 Diag(Def->getLocation(), diag::note_previous_definition); 6502 // If this is a redefinition, recover by making this 6503 // struct be anonymous, which will make any later 6504 // references get the previous definition. 6505 Name = 0; 6506 Previous.clear(); 6507 Invalid = true; 6508 } 6509 } else { 6510 // If the type is currently being defined, complain 6511 // about a nested redefinition. 6512 const TagType *Tag 6513 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 6514 if (Tag->isBeingDefined()) { 6515 Diag(NameLoc, diag::err_nested_redefinition) << Name; 6516 Diag(PrevTagDecl->getLocation(), 6517 diag::note_previous_definition); 6518 Name = 0; 6519 Previous.clear(); 6520 Invalid = true; 6521 } 6522 } 6523 6524 // Okay, this is definition of a previously declared or referenced 6525 // tag PrevDecl. We're going to create a new Decl for it. 6526 } 6527 } 6528 // If we get here we have (another) forward declaration or we 6529 // have a definition. Just create a new decl. 6530 6531 } else { 6532 // If we get here, this is a definition of a new tag type in a nested 6533 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 6534 // new decl/type. We set PrevDecl to NULL so that the entities 6535 // have distinct types. 6536 Previous.clear(); 6537 } 6538 // If we get here, we're going to create a new Decl. If PrevDecl 6539 // is non-NULL, it's a definition of the tag declared by 6540 // PrevDecl. If it's NULL, we have a new definition. 6541 6542 6543 // Otherwise, PrevDecl is not a tag, but was found with tag 6544 // lookup. This is only actually possible in C++, where a few 6545 // things like templates still live in the tag namespace. 6546 } else { 6547 assert(getLangOptions().CPlusPlus); 6548 6549 // Use a better diagnostic if an elaborated-type-specifier 6550 // found the wrong kind of type on the first 6551 // (non-redeclaration) lookup. 6552 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 6553 !Previous.isForRedeclaration()) { 6554 unsigned Kind = 0; 6555 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6556 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6557 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 6558 Diag(PrevDecl->getLocation(), diag::note_declared_at); 6559 Invalid = true; 6560 6561 // Otherwise, only diagnose if the declaration is in scope. 6562 } else if (!isDeclInScope(PrevDecl, SearchDC, S, 6563 isExplicitSpecialization)) { 6564 // do nothing 6565 6566 // Diagnose implicit declarations introduced by elaborated types. 6567 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 6568 unsigned Kind = 0; 6569 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6570 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6571 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 6572 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6573 Invalid = true; 6574 6575 // Otherwise it's a declaration. Call out a particularly common 6576 // case here. 6577 } else if (isa<TypedefDecl>(PrevDecl)) { 6578 Diag(NameLoc, diag::err_tag_definition_of_typedef) 6579 << Name 6580 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 6581 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6582 Invalid = true; 6583 6584 // Otherwise, diagnose. 6585 } else { 6586 // The tag name clashes with something else in the target scope, 6587 // issue an error and recover by making this tag be anonymous. 6588 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 6589 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6590 Name = 0; 6591 Invalid = true; 6592 } 6593 6594 // The existing declaration isn't relevant to us; we're in a 6595 // new scope, so clear out the previous declaration. 6596 Previous.clear(); 6597 } 6598 } 6599 6600CreateNewDecl: 6601 6602 TagDecl *PrevDecl = 0; 6603 if (Previous.isSingleResult()) 6604 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 6605 6606 // If there is an identifier, use the location of the identifier as the 6607 // location of the decl, otherwise use the location of the struct/union 6608 // keyword. 6609 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 6610 6611 // Otherwise, create a new declaration. If there is a previous 6612 // declaration of the same entity, the two will be linked via 6613 // PrevDecl. 6614 TagDecl *New; 6615 6616 bool IsForwardReference = false; 6617 if (Kind == TTK_Enum) { 6618 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6619 // enum X { A, B, C } D; D should chain to X. 6620 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, 6621 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 6622 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 6623 // If this is an undefined enum, warn. 6624 if (TUK != TUK_Definition && !Invalid) { 6625 TagDecl *Def; 6626 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 6627 // C++0x: 7.2p2: opaque-enum-declaration. 6628 // Conflicts are diagnosed above. Do nothing. 6629 } 6630 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 6631 Diag(Loc, diag::ext_forward_ref_enum_def) 6632 << New; 6633 Diag(Def->getLocation(), diag::note_previous_definition); 6634 } else { 6635 unsigned DiagID = diag::ext_forward_ref_enum; 6636 if (getLangOptions().Microsoft) 6637 DiagID = diag::ext_ms_forward_ref_enum; 6638 else if (getLangOptions().CPlusPlus) 6639 DiagID = diag::err_forward_ref_enum; 6640 Diag(Loc, DiagID); 6641 6642 // If this is a forward-declared reference to an enumeration, make a 6643 // note of it; we won't actually be introducing the declaration into 6644 // the declaration context. 6645 if (TUK == TUK_Reference) 6646 IsForwardReference = true; 6647 } 6648 } 6649 6650 if (EnumUnderlying) { 6651 EnumDecl *ED = cast<EnumDecl>(New); 6652 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6653 ED->setIntegerTypeSourceInfo(TI); 6654 else 6655 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 6656 ED->setPromotionType(ED->getIntegerType()); 6657 } 6658 6659 } else { 6660 // struct/union/class 6661 6662 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6663 // struct X { int A; } D; D should chain to X. 6664 if (getLangOptions().CPlusPlus) { 6665 // FIXME: Look for a way to use RecordDecl for simple structs. 6666 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 6667 cast_or_null<CXXRecordDecl>(PrevDecl)); 6668 6669 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 6670 StdBadAlloc = cast<CXXRecordDecl>(New); 6671 } else 6672 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 6673 cast_or_null<RecordDecl>(PrevDecl)); 6674 } 6675 6676 // Maybe add qualifier info. 6677 if (SS.isNotEmpty()) { 6678 if (SS.isSet()) { 6679 New->setQualifierInfo(SS.getWithLocInContext(Context)); 6680 if (TemplateParameterLists.size() > 0) { 6681 New->setTemplateParameterListsInfo(Context, 6682 TemplateParameterLists.size(), 6683 (TemplateParameterList**) TemplateParameterLists.release()); 6684 } 6685 } 6686 else 6687 Invalid = true; 6688 } 6689 6690 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 6691 // Add alignment attributes if necessary; these attributes are checked when 6692 // the ASTContext lays out the structure. 6693 // 6694 // It is important for implementing the correct semantics that this 6695 // happen here (in act on tag decl). The #pragma pack stack is 6696 // maintained as a result of parser callbacks which can occur at 6697 // many points during the parsing of a struct declaration (because 6698 // the #pragma tokens are effectively skipped over during the 6699 // parsing of the struct). 6700 AddAlignmentAttributesForRecord(RD); 6701 } 6702 6703 // If this is a specialization of a member class (of a class template), 6704 // check the specialization. 6705 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 6706 Invalid = true; 6707 6708 if (Invalid) 6709 New->setInvalidDecl(); 6710 6711 if (Attr) 6712 ProcessDeclAttributeList(S, New, Attr); 6713 6714 // If we're declaring or defining a tag in function prototype scope 6715 // in C, note that this type can only be used within the function. 6716 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6717 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6718 6719 // Set the lexical context. If the tag has a C++ scope specifier, the 6720 // lexical context will be different from the semantic context. 6721 New->setLexicalDeclContext(CurContext); 6722 6723 // Mark this as a friend decl if applicable. 6724 if (TUK == TUK_Friend) 6725 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6726 6727 // Set the access specifier. 6728 if (!Invalid && SearchDC->isRecord()) 6729 SetMemberAccessSpecifier(New, PrevDecl, AS); 6730 6731 if (TUK == TUK_Definition) 6732 New->startDefinition(); 6733 6734 // If this has an identifier, add it to the scope stack. 6735 if (TUK == TUK_Friend) { 6736 // We might be replacing an existing declaration in the lookup tables; 6737 // if so, borrow its access specifier. 6738 if (PrevDecl) 6739 New->setAccess(PrevDecl->getAccess()); 6740 6741 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6742 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6743 if (Name) // can be null along some error paths 6744 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6745 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6746 } else if (Name) { 6747 S = getNonFieldDeclScope(S); 6748 PushOnScopeChains(New, S, !IsForwardReference); 6749 if (IsForwardReference) 6750 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6751 6752 } else { 6753 CurContext->addDecl(New); 6754 } 6755 6756 // If this is the C FILE type, notify the AST context. 6757 if (IdentifierInfo *II = New->getIdentifier()) 6758 if (!New->isInvalidDecl() && 6759 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6760 II->isStr("FILE")) 6761 Context.setFILEDecl(New); 6762 6763 OwnedDecl = true; 6764 return New; 6765} 6766 6767void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6768 AdjustDeclIfTemplate(TagD); 6769 TagDecl *Tag = cast<TagDecl>(TagD); 6770 6771 // Enter the tag context. 6772 PushDeclContext(S, Tag); 6773} 6774 6775void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6776 SourceLocation FinalLoc, 6777 SourceLocation LBraceLoc) { 6778 AdjustDeclIfTemplate(TagD); 6779 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6780 6781 FieldCollector->StartClass(); 6782 6783 if (!Record->getIdentifier()) 6784 return; 6785 6786 if (FinalLoc.isValid()) 6787 Record->addAttr(new (Context) FinalAttr(FinalLoc, Context)); 6788 6789 // C++ [class]p2: 6790 // [...] The class-name is also inserted into the scope of the 6791 // class itself; this is known as the injected-class-name. For 6792 // purposes of access checking, the injected-class-name is treated 6793 // as if it were a public member name. 6794 CXXRecordDecl *InjectedClassName 6795 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, 6796 Record->getLocStart(), Record->getLocation(), 6797 Record->getIdentifier(), 6798 /*PrevDecl=*/0, 6799 /*DelayTypeCreation=*/true); 6800 Context.getTypeDeclType(InjectedClassName, Record); 6801 InjectedClassName->setImplicit(); 6802 InjectedClassName->setAccess(AS_public); 6803 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6804 InjectedClassName->setDescribedClassTemplate(Template); 6805 PushOnScopeChains(InjectedClassName, S); 6806 assert(InjectedClassName->isInjectedClassName() && 6807 "Broken injected-class-name"); 6808} 6809 6810void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6811 SourceLocation RBraceLoc) { 6812 AdjustDeclIfTemplate(TagD); 6813 TagDecl *Tag = cast<TagDecl>(TagD); 6814 Tag->setRBraceLoc(RBraceLoc); 6815 6816 if (isa<CXXRecordDecl>(Tag)) 6817 FieldCollector->FinishClass(); 6818 6819 // Exit this scope of this tag's definition. 6820 PopDeclContext(); 6821 6822 // Notify the consumer that we've defined a tag. 6823 Consumer.HandleTagDeclDefinition(Tag); 6824} 6825 6826void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6827 AdjustDeclIfTemplate(TagD); 6828 TagDecl *Tag = cast<TagDecl>(TagD); 6829 Tag->setInvalidDecl(); 6830 6831 // We're undoing ActOnTagStartDefinition here, not 6832 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6833 // the FieldCollector. 6834 6835 PopDeclContext(); 6836} 6837 6838// Note that FieldName may be null for anonymous bitfields. 6839bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6840 QualType FieldTy, const Expr *BitWidth, 6841 bool *ZeroWidth) { 6842 // Default to true; that shouldn't confuse checks for emptiness 6843 if (ZeroWidth) 6844 *ZeroWidth = true; 6845 6846 // C99 6.7.2.1p4 - verify the field type. 6847 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6848 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6849 // Handle incomplete types with specific error. 6850 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6851 return true; 6852 if (FieldName) 6853 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6854 << FieldName << FieldTy << BitWidth->getSourceRange(); 6855 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6856 << FieldTy << BitWidth->getSourceRange(); 6857 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 6858 UPPC_BitFieldWidth)) 6859 return true; 6860 6861 // If the bit-width is type- or value-dependent, don't try to check 6862 // it now. 6863 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6864 return false; 6865 6866 llvm::APSInt Value; 6867 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6868 return true; 6869 6870 if (Value != 0 && ZeroWidth) 6871 *ZeroWidth = false; 6872 6873 // Zero-width bitfield is ok for anonymous field. 6874 if (Value == 0 && FieldName) 6875 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6876 6877 if (Value.isSigned() && Value.isNegative()) { 6878 if (FieldName) 6879 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6880 << FieldName << Value.toString(10); 6881 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6882 << Value.toString(10); 6883 } 6884 6885 if (!FieldTy->isDependentType()) { 6886 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6887 if (Value.getZExtValue() > TypeSize) { 6888 if (!getLangOptions().CPlusPlus) { 6889 if (FieldName) 6890 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6891 << FieldName << (unsigned)Value.getZExtValue() 6892 << (unsigned)TypeSize; 6893 6894 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6895 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6896 } 6897 6898 if (FieldName) 6899 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6900 << FieldName << (unsigned)Value.getZExtValue() 6901 << (unsigned)TypeSize; 6902 else 6903 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6904 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6905 } 6906 } 6907 6908 return false; 6909} 6910 6911/// ActOnField - Each field of a struct/union/class is passed into this in order 6912/// to create a FieldDecl object for it. 6913Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6914 SourceLocation DeclStart, 6915 Declarator &D, ExprTy *BitfieldWidth) { 6916 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6917 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6918 AS_public); 6919 return Res; 6920} 6921 6922/// HandleField - Analyze a field of a C struct or a C++ data member. 6923/// 6924FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6925 SourceLocation DeclStart, 6926 Declarator &D, Expr *BitWidth, 6927 AccessSpecifier AS) { 6928 IdentifierInfo *II = D.getIdentifier(); 6929 SourceLocation Loc = DeclStart; 6930 if (II) Loc = D.getIdentifierLoc(); 6931 6932 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6933 QualType T = TInfo->getType(); 6934 if (getLangOptions().CPlusPlus) { 6935 CheckExtraCXXDefaultArguments(D); 6936 6937 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 6938 UPPC_DataMemberType)) { 6939 D.setInvalidType(); 6940 T = Context.IntTy; 6941 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 6942 } 6943 } 6944 6945 DiagnoseFunctionSpecifiers(D); 6946 6947 if (D.getDeclSpec().isThreadSpecified()) 6948 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6949 6950 // Check to see if this name was declared as a member previously 6951 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6952 LookupName(Previous, S); 6953 assert((Previous.empty() || Previous.isOverloadedResult() || 6954 Previous.isSingleResult()) 6955 && "Lookup of member name should be either overloaded, single or null"); 6956 6957 // If the name is overloaded then get any declaration else get the single result 6958 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6959 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6960 6961 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6962 // Maybe we will complain about the shadowed template parameter. 6963 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6964 // Just pretend that we didn't see the previous declaration. 6965 PrevDecl = 0; 6966 } 6967 6968 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6969 PrevDecl = 0; 6970 6971 bool Mutable 6972 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6973 SourceLocation TSSL = D.getSourceRange().getBegin(); 6974 FieldDecl *NewFD 6975 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6976 AS, PrevDecl, &D); 6977 6978 if (NewFD->isInvalidDecl()) 6979 Record->setInvalidDecl(); 6980 6981 if (NewFD->isInvalidDecl() && PrevDecl) { 6982 // Don't introduce NewFD into scope; there's already something 6983 // with the same name in the same scope. 6984 } else if (II) { 6985 PushOnScopeChains(NewFD, S); 6986 } else 6987 Record->addDecl(NewFD); 6988 6989 return NewFD; 6990} 6991 6992/// \brief Build a new FieldDecl and check its well-formedness. 6993/// 6994/// This routine builds a new FieldDecl given the fields name, type, 6995/// record, etc. \p PrevDecl should refer to any previous declaration 6996/// with the same name and in the same scope as the field to be 6997/// created. 6998/// 6999/// \returns a new FieldDecl. 7000/// 7001/// \todo The Declarator argument is a hack. It will be removed once 7002FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 7003 TypeSourceInfo *TInfo, 7004 RecordDecl *Record, SourceLocation Loc, 7005 bool Mutable, Expr *BitWidth, 7006 SourceLocation TSSL, 7007 AccessSpecifier AS, NamedDecl *PrevDecl, 7008 Declarator *D) { 7009 IdentifierInfo *II = Name.getAsIdentifierInfo(); 7010 bool InvalidDecl = false; 7011 if (D) InvalidDecl = D->isInvalidType(); 7012 7013 // If we receive a broken type, recover by assuming 'int' and 7014 // marking this declaration as invalid. 7015 if (T.isNull()) { 7016 InvalidDecl = true; 7017 T = Context.IntTy; 7018 } 7019 7020 QualType EltTy = Context.getBaseElementType(T); 7021 if (!EltTy->isDependentType() && 7022 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 7023 // Fields of incomplete type force their record to be invalid. 7024 Record->setInvalidDecl(); 7025 InvalidDecl = true; 7026 } 7027 7028 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7029 // than a variably modified type. 7030 if (!InvalidDecl && T->isVariablyModifiedType()) { 7031 bool SizeIsNegative; 7032 llvm::APSInt Oversized; 7033 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 7034 SizeIsNegative, 7035 Oversized); 7036 if (!FixedTy.isNull()) { 7037 Diag(Loc, diag::warn_illegal_constant_array_size); 7038 T = FixedTy; 7039 } else { 7040 if (SizeIsNegative) 7041 Diag(Loc, diag::err_typecheck_negative_array_size); 7042 else if (Oversized.getBoolValue()) 7043 Diag(Loc, diag::err_array_too_large) 7044 << Oversized.toString(10); 7045 else 7046 Diag(Loc, diag::err_typecheck_field_variable_size); 7047 InvalidDecl = true; 7048 } 7049 } 7050 7051 // Fields can not have abstract class types 7052 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 7053 diag::err_abstract_type_in_decl, 7054 AbstractFieldType)) 7055 InvalidDecl = true; 7056 7057 bool ZeroWidth = false; 7058 // If this is declared as a bit-field, check the bit-field. 7059 if (!InvalidDecl && BitWidth && 7060 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 7061 InvalidDecl = true; 7062 BitWidth = 0; 7063 ZeroWidth = false; 7064 } 7065 7066 // Check that 'mutable' is consistent with the type of the declaration. 7067 if (!InvalidDecl && Mutable) { 7068 unsigned DiagID = 0; 7069 if (T->isReferenceType()) 7070 DiagID = diag::err_mutable_reference; 7071 else if (T.isConstQualified()) 7072 DiagID = diag::err_mutable_const; 7073 7074 if (DiagID) { 7075 SourceLocation ErrLoc = Loc; 7076 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 7077 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 7078 Diag(ErrLoc, DiagID); 7079 Mutable = false; 7080 InvalidDecl = true; 7081 } 7082 } 7083 7084 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, 7085 BitWidth, Mutable); 7086 if (InvalidDecl) 7087 NewFD->setInvalidDecl(); 7088 7089 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 7090 Diag(Loc, diag::err_duplicate_member) << II; 7091 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7092 NewFD->setInvalidDecl(); 7093 } 7094 7095 if (!InvalidDecl && getLangOptions().CPlusPlus) { 7096 if (Record->isUnion()) { 7097 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7098 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7099 if (RDecl->getDefinition()) { 7100 // C++ [class.union]p1: An object of a class with a non-trivial 7101 // constructor, a non-trivial copy constructor, a non-trivial 7102 // destructor, or a non-trivial copy assignment operator 7103 // cannot be a member of a union, nor can an array of such 7104 // objects. 7105 // TODO: C++0x alters this restriction significantly. 7106 if (CheckNontrivialField(NewFD)) 7107 NewFD->setInvalidDecl(); 7108 } 7109 } 7110 7111 // C++ [class.union]p1: If a union contains a member of reference type, 7112 // the program is ill-formed. 7113 if (EltTy->isReferenceType()) { 7114 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 7115 << NewFD->getDeclName() << EltTy; 7116 NewFD->setInvalidDecl(); 7117 } 7118 } 7119 } 7120 7121 // FIXME: We need to pass in the attributes given an AST 7122 // representation, not a parser representation. 7123 if (D) 7124 // FIXME: What to pass instead of TUScope? 7125 ProcessDeclAttributes(TUScope, NewFD, *D); 7126 7127 if (T.isObjCGCWeak()) 7128 Diag(Loc, diag::warn_attribute_weak_on_field); 7129 7130 NewFD->setAccess(AS); 7131 return NewFD; 7132} 7133 7134bool Sema::CheckNontrivialField(FieldDecl *FD) { 7135 assert(FD); 7136 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 7137 7138 if (FD->isInvalidDecl()) 7139 return true; 7140 7141 QualType EltTy = Context.getBaseElementType(FD->getType()); 7142 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7143 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7144 if (RDecl->getDefinition()) { 7145 // We check for copy constructors before constructors 7146 // because otherwise we'll never get complaints about 7147 // copy constructors. 7148 7149 CXXSpecialMember member = CXXInvalid; 7150 if (!RDecl->hasTrivialCopyConstructor()) 7151 member = CXXCopyConstructor; 7152 else if (!RDecl->hasTrivialConstructor()) 7153 member = CXXConstructor; 7154 else if (!RDecl->hasTrivialCopyAssignment()) 7155 member = CXXCopyAssignment; 7156 else if (!RDecl->hasTrivialDestructor()) 7157 member = CXXDestructor; 7158 7159 if (member != CXXInvalid) { 7160 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7161 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7162 DiagnoseNontrivial(RT, member); 7163 return true; 7164 } 7165 } 7166 } 7167 7168 return false; 7169} 7170 7171/// DiagnoseNontrivial - Given that a class has a non-trivial 7172/// special member, figure out why. 7173void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7174 QualType QT(T, 0U); 7175 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7176 7177 // Check whether the member was user-declared. 7178 switch (member) { 7179 case CXXInvalid: 7180 break; 7181 7182 case CXXConstructor: 7183 if (RD->hasUserDeclaredConstructor()) { 7184 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7185 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7186 const FunctionDecl *body = 0; 7187 ci->hasBody(body); 7188 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7189 SourceLocation CtorLoc = ci->getLocation(); 7190 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7191 return; 7192 } 7193 } 7194 7195 assert(0 && "found no user-declared constructors"); 7196 return; 7197 } 7198 break; 7199 7200 case CXXCopyConstructor: 7201 if (RD->hasUserDeclaredCopyConstructor()) { 7202 SourceLocation CtorLoc = 7203 RD->getCopyConstructor(Context, 0)->getLocation(); 7204 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7205 return; 7206 } 7207 break; 7208 7209 case CXXCopyAssignment: 7210 if (RD->hasUserDeclaredCopyAssignment()) { 7211 // FIXME: this should use the location of the copy 7212 // assignment, not the type. 7213 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7214 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7215 return; 7216 } 7217 break; 7218 7219 case CXXDestructor: 7220 if (RD->hasUserDeclaredDestructor()) { 7221 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7222 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7223 return; 7224 } 7225 break; 7226 } 7227 7228 typedef CXXRecordDecl::base_class_iterator base_iter; 7229 7230 // Virtual bases and members inhibit trivial copying/construction, 7231 // but not trivial destruction. 7232 if (member != CXXDestructor) { 7233 // Check for virtual bases. vbases includes indirect virtual bases, 7234 // so we just iterate through the direct bases. 7235 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7236 if (bi->isVirtual()) { 7237 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7238 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7239 return; 7240 } 7241 7242 // Check for virtual methods. 7243 typedef CXXRecordDecl::method_iterator meth_iter; 7244 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 7245 ++mi) { 7246 if (mi->isVirtual()) { 7247 SourceLocation MLoc = mi->getSourceRange().getBegin(); 7248 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 7249 return; 7250 } 7251 } 7252 } 7253 7254 bool (CXXRecordDecl::*hasTrivial)() const; 7255 switch (member) { 7256 case CXXConstructor: 7257 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 7258 case CXXCopyConstructor: 7259 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 7260 case CXXCopyAssignment: 7261 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 7262 case CXXDestructor: 7263 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 7264 default: 7265 assert(0 && "unexpected special member"); return; 7266 } 7267 7268 // Check for nontrivial bases (and recurse). 7269 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 7270 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 7271 assert(BaseRT && "Don't know how to handle dependent bases"); 7272 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 7273 if (!(BaseRecTy->*hasTrivial)()) { 7274 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7275 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 7276 DiagnoseNontrivial(BaseRT, member); 7277 return; 7278 } 7279 } 7280 7281 // Check for nontrivial members (and recurse). 7282 typedef RecordDecl::field_iterator field_iter; 7283 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 7284 ++fi) { 7285 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 7286 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 7287 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 7288 7289 if (!(EltRD->*hasTrivial)()) { 7290 SourceLocation FLoc = (*fi)->getLocation(); 7291 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 7292 DiagnoseNontrivial(EltRT, member); 7293 return; 7294 } 7295 } 7296 } 7297 7298 assert(0 && "found no explanation for non-trivial member"); 7299} 7300 7301/// TranslateIvarVisibility - Translate visibility from a token ID to an 7302/// AST enum value. 7303static ObjCIvarDecl::AccessControl 7304TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 7305 switch (ivarVisibility) { 7306 default: assert(0 && "Unknown visitibility kind"); 7307 case tok::objc_private: return ObjCIvarDecl::Private; 7308 case tok::objc_public: return ObjCIvarDecl::Public; 7309 case tok::objc_protected: return ObjCIvarDecl::Protected; 7310 case tok::objc_package: return ObjCIvarDecl::Package; 7311 } 7312} 7313 7314/// ActOnIvar - Each ivar field of an objective-c class is passed into this 7315/// in order to create an IvarDecl object for it. 7316Decl *Sema::ActOnIvar(Scope *S, 7317 SourceLocation DeclStart, 7318 Decl *IntfDecl, 7319 Declarator &D, ExprTy *BitfieldWidth, 7320 tok::ObjCKeywordKind Visibility) { 7321 7322 IdentifierInfo *II = D.getIdentifier(); 7323 Expr *BitWidth = (Expr*)BitfieldWidth; 7324 SourceLocation Loc = DeclStart; 7325 if (II) Loc = D.getIdentifierLoc(); 7326 7327 // FIXME: Unnamed fields can be handled in various different ways, for 7328 // example, unnamed unions inject all members into the struct namespace! 7329 7330 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7331 QualType T = TInfo->getType(); 7332 7333 if (BitWidth) { 7334 // 6.7.2.1p3, 6.7.2.1p4 7335 if (VerifyBitField(Loc, II, T, BitWidth)) { 7336 D.setInvalidType(); 7337 BitWidth = 0; 7338 } 7339 } else { 7340 // Not a bitfield. 7341 7342 // validate II. 7343 7344 } 7345 if (T->isReferenceType()) { 7346 Diag(Loc, diag::err_ivar_reference_type); 7347 D.setInvalidType(); 7348 } 7349 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7350 // than a variably modified type. 7351 else if (T->isVariablyModifiedType()) { 7352 Diag(Loc, diag::err_typecheck_ivar_variable_size); 7353 D.setInvalidType(); 7354 } 7355 7356 // Get the visibility (access control) for this ivar. 7357 ObjCIvarDecl::AccessControl ac = 7358 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 7359 : ObjCIvarDecl::None; 7360 // Must set ivar's DeclContext to its enclosing interface. 7361 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 7362 ObjCContainerDecl *EnclosingContext; 7363 if (ObjCImplementationDecl *IMPDecl = 7364 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7365 if (!LangOpts.ObjCNonFragileABI2) { 7366 // Case of ivar declared in an implementation. Context is that of its class. 7367 EnclosingContext = IMPDecl->getClassInterface(); 7368 assert(EnclosingContext && "Implementation has no class interface!"); 7369 } 7370 else 7371 EnclosingContext = EnclosingDecl; 7372 } else { 7373 if (ObjCCategoryDecl *CDecl = 7374 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7375 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 7376 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 7377 return 0; 7378 } 7379 } 7380 EnclosingContext = EnclosingDecl; 7381 } 7382 7383 // Construct the decl. 7384 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, 7385 DeclStart, Loc, II, T, 7386 TInfo, ac, (Expr *)BitfieldWidth); 7387 7388 if (II) { 7389 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 7390 ForRedeclaration); 7391 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 7392 && !isa<TagDecl>(PrevDecl)) { 7393 Diag(Loc, diag::err_duplicate_member) << II; 7394 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7395 NewID->setInvalidDecl(); 7396 } 7397 } 7398 7399 // Process attributes attached to the ivar. 7400 ProcessDeclAttributes(S, NewID, D); 7401 7402 if (D.isInvalidType()) 7403 NewID->setInvalidDecl(); 7404 7405 if (II) { 7406 // FIXME: When interfaces are DeclContexts, we'll need to add 7407 // these to the interface. 7408 S->AddDecl(NewID); 7409 IdResolver.AddDecl(NewID); 7410 } 7411 7412 return NewID; 7413} 7414 7415/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 7416/// class and class extensions. For every class @interface and class 7417/// extension @interface, if the last ivar is a bitfield of any type, 7418/// then add an implicit `char :0` ivar to the end of that interface. 7419void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 7420 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 7421 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 7422 return; 7423 7424 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 7425 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 7426 7427 if (!Ivar->isBitField()) 7428 return; 7429 uint64_t BitFieldSize = 7430 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 7431 if (BitFieldSize == 0) 7432 return; 7433 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 7434 if (!ID) { 7435 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7436 if (!CD->IsClassExtension()) 7437 return; 7438 } 7439 // No need to add this to end of @implementation. 7440 else 7441 return; 7442 } 7443 // All conditions are met. Add a new bitfield to the tail end of ivars. 7444 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 7445 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 7446 7447 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 7448 DeclLoc, DeclLoc, 0, 7449 Context.CharTy, 7450 Context.CreateTypeSourceInfo(Context.CharTy), 7451 ObjCIvarDecl::Private, BW, 7452 true); 7453 AllIvarDecls.push_back(Ivar); 7454} 7455 7456void Sema::ActOnFields(Scope* S, 7457 SourceLocation RecLoc, Decl *EnclosingDecl, 7458 Decl **Fields, unsigned NumFields, 7459 SourceLocation LBrac, SourceLocation RBrac, 7460 AttributeList *Attr) { 7461 assert(EnclosingDecl && "missing record or interface decl"); 7462 7463 // If the decl this is being inserted into is invalid, then it may be a 7464 // redeclaration or some other bogus case. Don't try to add fields to it. 7465 if (EnclosingDecl->isInvalidDecl()) { 7466 // FIXME: Deallocate fields? 7467 return; 7468 } 7469 7470 7471 // Verify that all the fields are okay. 7472 unsigned NumNamedMembers = 0; 7473 llvm::SmallVector<FieldDecl*, 32> RecFields; 7474 7475 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 7476 for (unsigned i = 0; i != NumFields; ++i) { 7477 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 7478 7479 // Get the type for the field. 7480 const Type *FDTy = FD->getType().getTypePtr(); 7481 7482 if (!FD->isAnonymousStructOrUnion()) { 7483 // Remember all fields written by the user. 7484 RecFields.push_back(FD); 7485 } 7486 7487 // If the field is already invalid for some reason, don't emit more 7488 // diagnostics about it. 7489 if (FD->isInvalidDecl()) { 7490 EnclosingDecl->setInvalidDecl(); 7491 continue; 7492 } 7493 7494 // C99 6.7.2.1p2: 7495 // A structure or union shall not contain a member with 7496 // incomplete or function type (hence, a structure shall not 7497 // contain an instance of itself, but may contain a pointer to 7498 // an instance of itself), except that the last member of a 7499 // structure with more than one named member may have incomplete 7500 // array type; such a structure (and any union containing, 7501 // possibly recursively, a member that is such a structure) 7502 // shall not be a member of a structure or an element of an 7503 // array. 7504 if (FDTy->isFunctionType()) { 7505 // Field declared as a function. 7506 Diag(FD->getLocation(), diag::err_field_declared_as_function) 7507 << FD->getDeclName(); 7508 FD->setInvalidDecl(); 7509 EnclosingDecl->setInvalidDecl(); 7510 continue; 7511 } else if (FDTy->isIncompleteArrayType() && Record && 7512 ((i == NumFields - 1 && !Record->isUnion()) || 7513 ((getLangOptions().Microsoft || getLangOptions().CPlusPlus) && 7514 (i == NumFields - 1 || Record->isUnion())))) { 7515 // Flexible array member. 7516 // Microsoft and g++ is more permissive regarding flexible array. 7517 // It will accept flexible array in union and also 7518 // as the sole element of a struct/class. 7519 if (getLangOptions().Microsoft) { 7520 if (Record->isUnion()) 7521 Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) 7522 << FD->getDeclName(); 7523 else if (NumFields == 1) 7524 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) 7525 << FD->getDeclName() << Record->getTagKind(); 7526 } else if (getLangOptions().CPlusPlus) { 7527 if (Record->isUnion()) 7528 Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) 7529 << FD->getDeclName(); 7530 else if (NumFields == 1) 7531 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) 7532 << FD->getDeclName() << Record->getTagKind(); 7533 } else if (NumNamedMembers < 1) { 7534 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 7535 << FD->getDeclName(); 7536 FD->setInvalidDecl(); 7537 EnclosingDecl->setInvalidDecl(); 7538 continue; 7539 } 7540 if (!FD->getType()->isDependentType() && 7541 !Context.getBaseElementType(FD->getType())->isPODType()) { 7542 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 7543 << FD->getDeclName() << FD->getType(); 7544 FD->setInvalidDecl(); 7545 EnclosingDecl->setInvalidDecl(); 7546 continue; 7547 } 7548 // Okay, we have a legal flexible array member at the end of the struct. 7549 if (Record) 7550 Record->setHasFlexibleArrayMember(true); 7551 } else if (!FDTy->isDependentType() && 7552 RequireCompleteType(FD->getLocation(), FD->getType(), 7553 diag::err_field_incomplete)) { 7554 // Incomplete type 7555 FD->setInvalidDecl(); 7556 EnclosingDecl->setInvalidDecl(); 7557 continue; 7558 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 7559 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 7560 // If this is a member of a union, then entire union becomes "flexible". 7561 if (Record && Record->isUnion()) { 7562 Record->setHasFlexibleArrayMember(true); 7563 } else { 7564 // If this is a struct/class and this is not the last element, reject 7565 // it. Note that GCC supports variable sized arrays in the middle of 7566 // structures. 7567 if (i != NumFields-1) 7568 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 7569 << FD->getDeclName() << FD->getType(); 7570 else { 7571 // We support flexible arrays at the end of structs in 7572 // other structs as an extension. 7573 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 7574 << FD->getDeclName(); 7575 if (Record) 7576 Record->setHasFlexibleArrayMember(true); 7577 } 7578 } 7579 } 7580 if (Record && FDTTy->getDecl()->hasObjectMember()) 7581 Record->setHasObjectMember(true); 7582 } else if (FDTy->isObjCObjectType()) { 7583 /// A field cannot be an Objective-c object 7584 Diag(FD->getLocation(), diag::err_statically_allocated_object); 7585 FD->setInvalidDecl(); 7586 EnclosingDecl->setInvalidDecl(); 7587 continue; 7588 } else if (getLangOptions().ObjC1 && 7589 getLangOptions().getGCMode() != LangOptions::NonGC && 7590 Record && 7591 (FD->getType()->isObjCObjectPointerType() || 7592 FD->getType().isObjCGCStrong())) 7593 Record->setHasObjectMember(true); 7594 else if (Context.getAsArrayType(FD->getType())) { 7595 QualType BaseType = Context.getBaseElementType(FD->getType()); 7596 if (Record && BaseType->isRecordType() && 7597 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 7598 Record->setHasObjectMember(true); 7599 } 7600 // Keep track of the number of named members. 7601 if (FD->getIdentifier()) 7602 ++NumNamedMembers; 7603 } 7604 7605 // Okay, we successfully defined 'Record'. 7606 if (Record) { 7607 bool Completed = false; 7608 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 7609 if (!CXXRecord->isInvalidDecl()) { 7610 // Set access bits correctly on the directly-declared conversions. 7611 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 7612 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 7613 I != E; ++I) 7614 Convs->setAccess(I, (*I)->getAccess()); 7615 7616 if (!CXXRecord->isDependentType()) { 7617 // Add any implicitly-declared members to this class. 7618 AddImplicitlyDeclaredMembersToClass(CXXRecord); 7619 7620 // If we have virtual base classes, we may end up finding multiple 7621 // final overriders for a given virtual function. Check for this 7622 // problem now. 7623 if (CXXRecord->getNumVBases()) { 7624 CXXFinalOverriderMap FinalOverriders; 7625 CXXRecord->getFinalOverriders(FinalOverriders); 7626 7627 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 7628 MEnd = FinalOverriders.end(); 7629 M != MEnd; ++M) { 7630 for (OverridingMethods::iterator SO = M->second.begin(), 7631 SOEnd = M->second.end(); 7632 SO != SOEnd; ++SO) { 7633 assert(SO->second.size() > 0 && 7634 "Virtual function without overridding functions?"); 7635 if (SO->second.size() == 1) 7636 continue; 7637 7638 // C++ [class.virtual]p2: 7639 // In a derived class, if a virtual member function of a base 7640 // class subobject has more than one final overrider the 7641 // program is ill-formed. 7642 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 7643 << (NamedDecl *)M->first << Record; 7644 Diag(M->first->getLocation(), 7645 diag::note_overridden_virtual_function); 7646 for (OverridingMethods::overriding_iterator 7647 OM = SO->second.begin(), 7648 OMEnd = SO->second.end(); 7649 OM != OMEnd; ++OM) 7650 Diag(OM->Method->getLocation(), diag::note_final_overrider) 7651 << (NamedDecl *)M->first << OM->Method->getParent(); 7652 7653 Record->setInvalidDecl(); 7654 } 7655 } 7656 CXXRecord->completeDefinition(&FinalOverriders); 7657 Completed = true; 7658 } 7659 } 7660 } 7661 } 7662 7663 if (!Completed) 7664 Record->completeDefinition(); 7665 } else { 7666 ObjCIvarDecl **ClsFields = 7667 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 7668 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 7669 ID->setLocEnd(RBrac); 7670 // Add ivar's to class's DeclContext. 7671 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7672 ClsFields[i]->setLexicalDeclContext(ID); 7673 ID->addDecl(ClsFields[i]); 7674 } 7675 // Must enforce the rule that ivars in the base classes may not be 7676 // duplicates. 7677 if (ID->getSuperClass()) 7678 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 7679 } else if (ObjCImplementationDecl *IMPDecl = 7680 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7681 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 7682 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 7683 // Ivar declared in @implementation never belongs to the implementation. 7684 // Only it is in implementation's lexical context. 7685 ClsFields[I]->setLexicalDeclContext(IMPDecl); 7686 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 7687 } else if (ObjCCategoryDecl *CDecl = 7688 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7689 // case of ivars in class extension; all other cases have been 7690 // reported as errors elsewhere. 7691 // FIXME. Class extension does not have a LocEnd field. 7692 // CDecl->setLocEnd(RBrac); 7693 // Add ivar's to class extension's DeclContext. 7694 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7695 ClsFields[i]->setLexicalDeclContext(CDecl); 7696 CDecl->addDecl(ClsFields[i]); 7697 } 7698 } 7699 } 7700 7701 if (Attr) 7702 ProcessDeclAttributeList(S, Record, Attr); 7703 7704 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 7705 // set the visibility of this record. 7706 if (Record && !Record->getDeclContext()->isRecord()) 7707 AddPushedVisibilityAttribute(Record); 7708} 7709 7710/// \brief Determine whether the given integral value is representable within 7711/// the given type T. 7712static bool isRepresentableIntegerValue(ASTContext &Context, 7713 llvm::APSInt &Value, 7714 QualType T) { 7715 assert(T->isIntegralType(Context) && "Integral type required!"); 7716 unsigned BitWidth = Context.getIntWidth(T); 7717 7718 if (Value.isUnsigned() || Value.isNonNegative()) { 7719 if (T->isSignedIntegerType()) 7720 --BitWidth; 7721 return Value.getActiveBits() <= BitWidth; 7722 } 7723 return Value.getMinSignedBits() <= BitWidth; 7724} 7725 7726// \brief Given an integral type, return the next larger integral type 7727// (or a NULL type of no such type exists). 7728static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 7729 // FIXME: Int128/UInt128 support, which also needs to be introduced into 7730 // enum checking below. 7731 assert(T->isIntegralType(Context) && "Integral type required!"); 7732 const unsigned NumTypes = 4; 7733 QualType SignedIntegralTypes[NumTypes] = { 7734 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 7735 }; 7736 QualType UnsignedIntegralTypes[NumTypes] = { 7737 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 7738 Context.UnsignedLongLongTy 7739 }; 7740 7741 unsigned BitWidth = Context.getTypeSize(T); 7742 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7743 : UnsignedIntegralTypes; 7744 for (unsigned I = 0; I != NumTypes; ++I) 7745 if (Context.getTypeSize(Types[I]) > BitWidth) 7746 return Types[I]; 7747 7748 return QualType(); 7749} 7750 7751EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7752 EnumConstantDecl *LastEnumConst, 7753 SourceLocation IdLoc, 7754 IdentifierInfo *Id, 7755 Expr *Val) { 7756 unsigned IntWidth = Context.Target.getIntWidth(); 7757 llvm::APSInt EnumVal(IntWidth); 7758 QualType EltTy; 7759 7760 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 7761 Val = 0; 7762 7763 if (Val) { 7764 if (Enum->isDependentType() || Val->isTypeDependent()) 7765 EltTy = Context.DependentTy; 7766 else { 7767 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7768 SourceLocation ExpLoc; 7769 if (!Val->isValueDependent() && 7770 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7771 Val = 0; 7772 } else { 7773 if (!getLangOptions().CPlusPlus) { 7774 // C99 6.7.2.2p2: 7775 // The expression that defines the value of an enumeration constant 7776 // shall be an integer constant expression that has a value 7777 // representable as an int. 7778 7779 // Complain if the value is not representable in an int. 7780 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7781 Diag(IdLoc, diag::ext_enum_value_not_int) 7782 << EnumVal.toString(10) << Val->getSourceRange() 7783 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7784 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7785 // Force the type of the expression to 'int'. 7786 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).take(); 7787 } 7788 } 7789 7790 if (Enum->isFixed()) { 7791 EltTy = Enum->getIntegerType(); 7792 7793 // C++0x [dcl.enum]p5: 7794 // ... if the initializing value of an enumerator cannot be 7795 // represented by the underlying type, the program is ill-formed. 7796 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7797 if (getLangOptions().Microsoft) { 7798 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 7799 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 7800 } else 7801 Diag(IdLoc, diag::err_enumerator_too_large) 7802 << EltTy; 7803 } else 7804 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 7805 } 7806 else { 7807 // C++0x [dcl.enum]p5: 7808 // If the underlying type is not fixed, the type of each enumerator 7809 // is the type of its initializing value: 7810 // - If an initializer is specified for an enumerator, the 7811 // initializing value has the same type as the expression. 7812 EltTy = Val->getType(); 7813 } 7814 } 7815 } 7816 } 7817 7818 if (!Val) { 7819 if (Enum->isDependentType()) 7820 EltTy = Context.DependentTy; 7821 else if (!LastEnumConst) { 7822 // C++0x [dcl.enum]p5: 7823 // If the underlying type is not fixed, the type of each enumerator 7824 // is the type of its initializing value: 7825 // - If no initializer is specified for the first enumerator, the 7826 // initializing value has an unspecified integral type. 7827 // 7828 // GCC uses 'int' for its unspecified integral type, as does 7829 // C99 6.7.2.2p3. 7830 if (Enum->isFixed()) { 7831 EltTy = Enum->getIntegerType(); 7832 } 7833 else { 7834 EltTy = Context.IntTy; 7835 } 7836 } else { 7837 // Assign the last value + 1. 7838 EnumVal = LastEnumConst->getInitVal(); 7839 ++EnumVal; 7840 EltTy = LastEnumConst->getType(); 7841 7842 // Check for overflow on increment. 7843 if (EnumVal < LastEnumConst->getInitVal()) { 7844 // C++0x [dcl.enum]p5: 7845 // If the underlying type is not fixed, the type of each enumerator 7846 // is the type of its initializing value: 7847 // 7848 // - Otherwise the type of the initializing value is the same as 7849 // the type of the initializing value of the preceding enumerator 7850 // unless the incremented value is not representable in that type, 7851 // in which case the type is an unspecified integral type 7852 // sufficient to contain the incremented value. If no such type 7853 // exists, the program is ill-formed. 7854 QualType T = getNextLargerIntegralType(Context, EltTy); 7855 if (T.isNull() || Enum->isFixed()) { 7856 // There is no integral type larger enough to represent this 7857 // value. Complain, then allow the value to wrap around. 7858 EnumVal = LastEnumConst->getInitVal(); 7859 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 7860 ++EnumVal; 7861 if (Enum->isFixed()) 7862 // When the underlying type is fixed, this is ill-formed. 7863 Diag(IdLoc, diag::err_enumerator_wrapped) 7864 << EnumVal.toString(10) 7865 << EltTy; 7866 else 7867 Diag(IdLoc, diag::warn_enumerator_too_large) 7868 << EnumVal.toString(10); 7869 } else { 7870 EltTy = T; 7871 } 7872 7873 // Retrieve the last enumerator's value, extent that type to the 7874 // type that is supposed to be large enough to represent the incremented 7875 // value, then increment. 7876 EnumVal = LastEnumConst->getInitVal(); 7877 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7878 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7879 ++EnumVal; 7880 7881 // If we're not in C++, diagnose the overflow of enumerator values, 7882 // which in C99 means that the enumerator value is not representable in 7883 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7884 // permits enumerator values that are representable in some larger 7885 // integral type. 7886 if (!getLangOptions().CPlusPlus && !T.isNull()) 7887 Diag(IdLoc, diag::warn_enum_value_overflow); 7888 } else if (!getLangOptions().CPlusPlus && 7889 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7890 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7891 Diag(IdLoc, diag::ext_enum_value_not_int) 7892 << EnumVal.toString(10) << 1; 7893 } 7894 } 7895 } 7896 7897 if (!EltTy->isDependentType()) { 7898 // Make the enumerator value match the signedness and size of the 7899 // enumerator's type. 7900 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7901 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7902 } 7903 7904 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7905 Val, EnumVal); 7906} 7907 7908 7909Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 7910 SourceLocation IdLoc, IdentifierInfo *Id, 7911 AttributeList *Attr, 7912 SourceLocation EqualLoc, ExprTy *val) { 7913 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7914 EnumConstantDecl *LastEnumConst = 7915 cast_or_null<EnumConstantDecl>(lastEnumConst); 7916 Expr *Val = static_cast<Expr*>(val); 7917 7918 // The scope passed in may not be a decl scope. Zip up the scope tree until 7919 // we find one that is. 7920 S = getNonFieldDeclScope(S); 7921 7922 // Verify that there isn't already something declared with this name in this 7923 // scope. 7924 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7925 ForRedeclaration); 7926 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7927 // Maybe we will complain about the shadowed template parameter. 7928 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7929 // Just pretend that we didn't see the previous declaration. 7930 PrevDecl = 0; 7931 } 7932 7933 if (PrevDecl) { 7934 // When in C++, we may get a TagDecl with the same name; in this case the 7935 // enum constant will 'hide' the tag. 7936 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7937 "Received TagDecl when not in C++!"); 7938 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7939 if (isa<EnumConstantDecl>(PrevDecl)) 7940 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7941 else 7942 Diag(IdLoc, diag::err_redefinition) << Id; 7943 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7944 return 0; 7945 } 7946 } 7947 7948 // C++ [class.mem]p13: 7949 // If T is the name of a class, then each of the following shall have a 7950 // name different from T: 7951 // - every enumerator of every member of class T that is an enumerated 7952 // type 7953 if (CXXRecordDecl *Record 7954 = dyn_cast<CXXRecordDecl>( 7955 TheEnumDecl->getDeclContext()->getRedeclContext())) 7956 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7957 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7958 7959 EnumConstantDecl *New = 7960 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 7961 7962 if (New) { 7963 // Process attributes. 7964 if (Attr) ProcessDeclAttributeList(S, New, Attr); 7965 7966 // Register this decl in the current scope stack. 7967 New->setAccess(TheEnumDecl->getAccess()); 7968 PushOnScopeChains(New, S); 7969 } 7970 7971 return New; 7972} 7973 7974void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7975 SourceLocation RBraceLoc, Decl *EnumDeclX, 7976 Decl **Elements, unsigned NumElements, 7977 Scope *S, AttributeList *Attr) { 7978 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7979 QualType EnumType = Context.getTypeDeclType(Enum); 7980 7981 if (Attr) 7982 ProcessDeclAttributeList(S, Enum, Attr); 7983 7984 if (Enum->isDependentType()) { 7985 for (unsigned i = 0; i != NumElements; ++i) { 7986 EnumConstantDecl *ECD = 7987 cast_or_null<EnumConstantDecl>(Elements[i]); 7988 if (!ECD) continue; 7989 7990 ECD->setType(EnumType); 7991 } 7992 7993 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7994 return; 7995 } 7996 7997 // TODO: If the result value doesn't fit in an int, it must be a long or long 7998 // long value. ISO C does not support this, but GCC does as an extension, 7999 // emit a warning. 8000 unsigned IntWidth = Context.Target.getIntWidth(); 8001 unsigned CharWidth = Context.Target.getCharWidth(); 8002 unsigned ShortWidth = Context.Target.getShortWidth(); 8003 8004 // Verify that all the values are okay, compute the size of the values, and 8005 // reverse the list. 8006 unsigned NumNegativeBits = 0; 8007 unsigned NumPositiveBits = 0; 8008 8009 // Keep track of whether all elements have type int. 8010 bool AllElementsInt = true; 8011 8012 for (unsigned i = 0; i != NumElements; ++i) { 8013 EnumConstantDecl *ECD = 8014 cast_or_null<EnumConstantDecl>(Elements[i]); 8015 if (!ECD) continue; // Already issued a diagnostic. 8016 8017 const llvm::APSInt &InitVal = ECD->getInitVal(); 8018 8019 // Keep track of the size of positive and negative values. 8020 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 8021 NumPositiveBits = std::max(NumPositiveBits, 8022 (unsigned)InitVal.getActiveBits()); 8023 else 8024 NumNegativeBits = std::max(NumNegativeBits, 8025 (unsigned)InitVal.getMinSignedBits()); 8026 8027 // Keep track of whether every enum element has type int (very commmon). 8028 if (AllElementsInt) 8029 AllElementsInt = ECD->getType() == Context.IntTy; 8030 } 8031 8032 // Figure out the type that should be used for this enum. 8033 QualType BestType; 8034 unsigned BestWidth; 8035 8036 // C++0x N3000 [conv.prom]p3: 8037 // An rvalue of an unscoped enumeration type whose underlying 8038 // type is not fixed can be converted to an rvalue of the first 8039 // of the following types that can represent all the values of 8040 // the enumeration: int, unsigned int, long int, unsigned long 8041 // int, long long int, or unsigned long long int. 8042 // C99 6.4.4.3p2: 8043 // An identifier declared as an enumeration constant has type int. 8044 // The C99 rule is modified by a gcc extension 8045 QualType BestPromotionType; 8046 8047 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 8048 // -fshort-enums is the equivalent to specifying the packed attribute on all 8049 // enum definitions. 8050 if (LangOpts.ShortEnums) 8051 Packed = true; 8052 8053 if (Enum->isFixed()) { 8054 BestType = BestPromotionType = Enum->getIntegerType(); 8055 // We don't need to set BestWidth, because BestType is going to be the type 8056 // of the enumerators, but we do anyway because otherwise some compilers 8057 // warn that it might be used uninitialized. 8058 BestWidth = CharWidth; 8059 } 8060 else if (NumNegativeBits) { 8061 // If there is a negative value, figure out the smallest integer type (of 8062 // int/long/longlong) that fits. 8063 // If it's packed, check also if it fits a char or a short. 8064 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 8065 BestType = Context.SignedCharTy; 8066 BestWidth = CharWidth; 8067 } else if (Packed && NumNegativeBits <= ShortWidth && 8068 NumPositiveBits < ShortWidth) { 8069 BestType = Context.ShortTy; 8070 BestWidth = ShortWidth; 8071 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 8072 BestType = Context.IntTy; 8073 BestWidth = IntWidth; 8074 } else { 8075 BestWidth = Context.Target.getLongWidth(); 8076 8077 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 8078 BestType = Context.LongTy; 8079 } else { 8080 BestWidth = Context.Target.getLongLongWidth(); 8081 8082 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 8083 Diag(Enum->getLocation(), diag::warn_enum_too_large); 8084 BestType = Context.LongLongTy; 8085 } 8086 } 8087 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 8088 } else { 8089 // If there is no negative value, figure out the smallest type that fits 8090 // all of the enumerator values. 8091 // If it's packed, check also if it fits a char or a short. 8092 if (Packed && NumPositiveBits <= CharWidth) { 8093 BestType = Context.UnsignedCharTy; 8094 BestPromotionType = Context.IntTy; 8095 BestWidth = CharWidth; 8096 } else if (Packed && NumPositiveBits <= ShortWidth) { 8097 BestType = Context.UnsignedShortTy; 8098 BestPromotionType = Context.IntTy; 8099 BestWidth = ShortWidth; 8100 } else if (NumPositiveBits <= IntWidth) { 8101 BestType = Context.UnsignedIntTy; 8102 BestWidth = IntWidth; 8103 BestPromotionType 8104 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8105 ? Context.UnsignedIntTy : Context.IntTy; 8106 } else if (NumPositiveBits <= 8107 (BestWidth = Context.Target.getLongWidth())) { 8108 BestType = Context.UnsignedLongTy; 8109 BestPromotionType 8110 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8111 ? Context.UnsignedLongTy : Context.LongTy; 8112 } else { 8113 BestWidth = Context.Target.getLongLongWidth(); 8114 assert(NumPositiveBits <= BestWidth && 8115 "How could an initializer get larger than ULL?"); 8116 BestType = Context.UnsignedLongLongTy; 8117 BestPromotionType 8118 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8119 ? Context.UnsignedLongLongTy : Context.LongLongTy; 8120 } 8121 } 8122 8123 // Loop over all of the enumerator constants, changing their types to match 8124 // the type of the enum if needed. 8125 for (unsigned i = 0; i != NumElements; ++i) { 8126 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 8127 if (!ECD) continue; // Already issued a diagnostic. 8128 8129 // Standard C says the enumerators have int type, but we allow, as an 8130 // extension, the enumerators to be larger than int size. If each 8131 // enumerator value fits in an int, type it as an int, otherwise type it the 8132 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 8133 // that X has type 'int', not 'unsigned'. 8134 8135 // Determine whether the value fits into an int. 8136 llvm::APSInt InitVal = ECD->getInitVal(); 8137 8138 // If it fits into an integer type, force it. Otherwise force it to match 8139 // the enum decl type. 8140 QualType NewTy; 8141 unsigned NewWidth; 8142 bool NewSign; 8143 if (!getLangOptions().CPlusPlus && 8144 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 8145 NewTy = Context.IntTy; 8146 NewWidth = IntWidth; 8147 NewSign = true; 8148 } else if (ECD->getType() == BestType) { 8149 // Already the right type! 8150 if (getLangOptions().CPlusPlus) 8151 // C++ [dcl.enum]p4: Following the closing brace of an 8152 // enum-specifier, each enumerator has the type of its 8153 // enumeration. 8154 ECD->setType(EnumType); 8155 continue; 8156 } else { 8157 NewTy = BestType; 8158 NewWidth = BestWidth; 8159 NewSign = BestType->isSignedIntegerType(); 8160 } 8161 8162 // Adjust the APSInt value. 8163 InitVal = InitVal.extOrTrunc(NewWidth); 8164 InitVal.setIsSigned(NewSign); 8165 ECD->setInitVal(InitVal); 8166 8167 // Adjust the Expr initializer and type. 8168 if (ECD->getInitExpr() && 8169 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 8170 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 8171 CK_IntegralCast, 8172 ECD->getInitExpr(), 8173 /*base paths*/ 0, 8174 VK_RValue)); 8175 if (getLangOptions().CPlusPlus) 8176 // C++ [dcl.enum]p4: Following the closing brace of an 8177 // enum-specifier, each enumerator has the type of its 8178 // enumeration. 8179 ECD->setType(EnumType); 8180 else 8181 ECD->setType(NewTy); 8182 } 8183 8184 Enum->completeDefinition(BestType, BestPromotionType, 8185 NumPositiveBits, NumNegativeBits); 8186} 8187 8188Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 8189 SourceLocation StartLoc, 8190 SourceLocation EndLoc) { 8191 StringLiteral *AsmString = cast<StringLiteral>(expr); 8192 8193 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 8194 AsmString, StartLoc, 8195 EndLoc); 8196 CurContext->addDecl(New); 8197 return New; 8198} 8199 8200void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 8201 SourceLocation PragmaLoc, 8202 SourceLocation NameLoc) { 8203 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 8204 8205 if (PrevDecl) { 8206 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 8207 } else { 8208 (void)WeakUndeclaredIdentifiers.insert( 8209 std::pair<IdentifierInfo*,WeakInfo> 8210 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 8211 } 8212} 8213 8214void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 8215 IdentifierInfo* AliasName, 8216 SourceLocation PragmaLoc, 8217 SourceLocation NameLoc, 8218 SourceLocation AliasNameLoc) { 8219 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 8220 LookupOrdinaryName); 8221 WeakInfo W = WeakInfo(Name, NameLoc); 8222 8223 if (PrevDecl) { 8224 if (!PrevDecl->hasAttr<AliasAttr>()) 8225 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 8226 DeclApplyPragmaWeak(TUScope, ND, W); 8227 } else { 8228 (void)WeakUndeclaredIdentifiers.insert( 8229 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 8230 } 8231} 8232