SemaDecl.cpp revision 337ec3d0e8cb24a591ecbecdc0a995a167f6af01
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "clang/AST/APValue.h" 21#include "clang/AST/ASTConsumer.h" 22#include "clang/AST/ASTContext.h" 23#include "clang/AST/CXXInheritance.h" 24#include "clang/AST/DeclCXX.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/DeclTemplate.h" 27#include "clang/AST/ExprCXX.h" 28#include "clang/AST/StmtCXX.h" 29#include "clang/Sema/DeclSpec.h" 30#include "clang/Sema/ParsedTemplate.h" 31#include "clang/Parse/ParseDiagnostic.h" 32#include "clang/Basic/PartialDiagnostic.h" 33#include "clang/Basic/SourceManager.h" 34#include "clang/Basic/TargetInfo.h" 35// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 36#include "clang/Lex/Preprocessor.h" 37#include "clang/Lex/HeaderSearch.h" 38#include "llvm/ADT/Triple.h" 39#include <algorithm> 40#include <cstring> 41#include <functional> 42using namespace clang; 43using namespace sema; 44 45Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 46 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 47} 48 49/// \brief If the identifier refers to a type name within this scope, 50/// return the declaration of that type. 51/// 52/// This routine performs ordinary name lookup of the identifier II 53/// within the given scope, with optional C++ scope specifier SS, to 54/// determine whether the name refers to a type. If so, returns an 55/// opaque pointer (actually a QualType) corresponding to that 56/// type. Otherwise, returns NULL. 57/// 58/// If name lookup results in an ambiguity, this routine will complain 59/// and then return NULL. 60ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 61 Scope *S, CXXScopeSpec *SS, 62 bool isClassName, 63 ParsedType ObjectTypePtr) { 64 // Determine where we will perform name lookup. 65 DeclContext *LookupCtx = 0; 66 if (ObjectTypePtr) { 67 QualType ObjectType = ObjectTypePtr.get(); 68 if (ObjectType->isRecordType()) 69 LookupCtx = computeDeclContext(ObjectType); 70 } else if (SS && SS->isNotEmpty()) { 71 LookupCtx = computeDeclContext(*SS, false); 72 73 if (!LookupCtx) { 74 if (isDependentScopeSpecifier(*SS)) { 75 // C++ [temp.res]p3: 76 // A qualified-id that refers to a type and in which the 77 // nested-name-specifier depends on a template-parameter (14.6.2) 78 // shall be prefixed by the keyword typename to indicate that the 79 // qualified-id denotes a type, forming an 80 // elaborated-type-specifier (7.1.5.3). 81 // 82 // We therefore do not perform any name lookup if the result would 83 // refer to a member of an unknown specialization. 84 if (!isClassName) 85 return ParsedType(); 86 87 // We know from the grammar that this name refers to a type, 88 // so build a dependent node to describe the type. 89 QualType T = 90 CheckTypenameType(ETK_None, SS->getScopeRep(), II, 91 SourceLocation(), SS->getRange(), NameLoc); 92 return ParsedType::make(T); 93 } 94 95 return ParsedType(); 96 } 97 98 if (!LookupCtx->isDependentContext() && 99 RequireCompleteDeclContext(*SS, LookupCtx)) 100 return ParsedType(); 101 } 102 103 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 104 // lookup for class-names. 105 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 106 LookupOrdinaryName; 107 LookupResult Result(*this, &II, NameLoc, Kind); 108 if (LookupCtx) { 109 // Perform "qualified" name lookup into the declaration context we 110 // computed, which is either the type of the base of a member access 111 // expression or the declaration context associated with a prior 112 // nested-name-specifier. 113 LookupQualifiedName(Result, LookupCtx); 114 115 if (ObjectTypePtr && Result.empty()) { 116 // C++ [basic.lookup.classref]p3: 117 // If the unqualified-id is ~type-name, the type-name is looked up 118 // in the context of the entire postfix-expression. If the type T of 119 // the object expression is of a class type C, the type-name is also 120 // looked up in the scope of class C. At least one of the lookups shall 121 // find a name that refers to (possibly cv-qualified) T. 122 LookupName(Result, S); 123 } 124 } else { 125 // Perform unqualified name lookup. 126 LookupName(Result, S); 127 } 128 129 NamedDecl *IIDecl = 0; 130 switch (Result.getResultKind()) { 131 case LookupResult::NotFound: 132 case LookupResult::NotFoundInCurrentInstantiation: 133 case LookupResult::FoundOverloaded: 134 case LookupResult::FoundUnresolvedValue: 135 Result.suppressDiagnostics(); 136 return ParsedType(); 137 138 case LookupResult::Ambiguous: 139 // Recover from type-hiding ambiguities by hiding the type. We'll 140 // do the lookup again when looking for an object, and we can 141 // diagnose the error then. If we don't do this, then the error 142 // about hiding the type will be immediately followed by an error 143 // that only makes sense if the identifier was treated like a type. 144 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 145 Result.suppressDiagnostics(); 146 return ParsedType(); 147 } 148 149 // Look to see if we have a type anywhere in the list of results. 150 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 151 Res != ResEnd; ++Res) { 152 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 153 if (!IIDecl || 154 (*Res)->getLocation().getRawEncoding() < 155 IIDecl->getLocation().getRawEncoding()) 156 IIDecl = *Res; 157 } 158 } 159 160 if (!IIDecl) { 161 // None of the entities we found is a type, so there is no way 162 // to even assume that the result is a type. In this case, don't 163 // complain about the ambiguity. The parser will either try to 164 // perform this lookup again (e.g., as an object name), which 165 // will produce the ambiguity, or will complain that it expected 166 // a type name. 167 Result.suppressDiagnostics(); 168 return ParsedType(); 169 } 170 171 // We found a type within the ambiguous lookup; diagnose the 172 // ambiguity and then return that type. This might be the right 173 // answer, or it might not be, but it suppresses any attempt to 174 // perform the name lookup again. 175 break; 176 177 case LookupResult::Found: 178 IIDecl = Result.getFoundDecl(); 179 break; 180 } 181 182 assert(IIDecl && "Didn't find decl"); 183 184 QualType T; 185 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 186 DiagnoseUseOfDecl(IIDecl, NameLoc); 187 188 if (T.isNull()) 189 T = Context.getTypeDeclType(TD); 190 191 if (SS) 192 T = getElaboratedType(ETK_None, *SS, T); 193 194 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 195 T = Context.getObjCInterfaceType(IDecl); 196 } else { 197 // If it's not plausibly a type, suppress diagnostics. 198 Result.suppressDiagnostics(); 199 return ParsedType(); 200 } 201 202 return ParsedType::make(T); 203} 204 205/// isTagName() - This method is called *for error recovery purposes only* 206/// to determine if the specified name is a valid tag name ("struct foo"). If 207/// so, this returns the TST for the tag corresponding to it (TST_enum, 208/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 209/// where the user forgot to specify the tag. 210DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 211 // Do a tag name lookup in this scope. 212 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 213 LookupName(R, S, false); 214 R.suppressDiagnostics(); 215 if (R.getResultKind() == LookupResult::Found) 216 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 217 switch (TD->getTagKind()) { 218 default: return DeclSpec::TST_unspecified; 219 case TTK_Struct: return DeclSpec::TST_struct; 220 case TTK_Union: return DeclSpec::TST_union; 221 case TTK_Class: return DeclSpec::TST_class; 222 case TTK_Enum: return DeclSpec::TST_enum; 223 } 224 } 225 226 return DeclSpec::TST_unspecified; 227} 228 229bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 230 SourceLocation IILoc, 231 Scope *S, 232 CXXScopeSpec *SS, 233 ParsedType &SuggestedType) { 234 // We don't have anything to suggest (yet). 235 SuggestedType = ParsedType(); 236 237 // There may have been a typo in the name of the type. Look up typo 238 // results, in case we have something that we can suggest. 239 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 240 NotForRedeclaration); 241 242 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 243 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 244 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 245 !Result->isInvalidDecl()) { 246 // We found a similarly-named type or interface; suggest that. 247 if (!SS || !SS->isSet()) 248 Diag(IILoc, diag::err_unknown_typename_suggest) 249 << &II << Lookup.getLookupName() 250 << FixItHint::CreateReplacement(SourceRange(IILoc), 251 Result->getNameAsString()); 252 else if (DeclContext *DC = computeDeclContext(*SS, false)) 253 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 254 << &II << DC << Lookup.getLookupName() << SS->getRange() 255 << FixItHint::CreateReplacement(SourceRange(IILoc), 256 Result->getNameAsString()); 257 else 258 llvm_unreachable("could not have corrected a typo here"); 259 260 Diag(Result->getLocation(), diag::note_previous_decl) 261 << Result->getDeclName(); 262 263 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 264 return true; 265 } 266 } else if (Lookup.empty()) { 267 // We corrected to a keyword. 268 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 269 Diag(IILoc, diag::err_unknown_typename_suggest) 270 << &II << Corrected; 271 return true; 272 } 273 } 274 275 if (getLangOptions().CPlusPlus) { 276 // See if II is a class template that the user forgot to pass arguments to. 277 UnqualifiedId Name; 278 Name.setIdentifier(&II, IILoc); 279 CXXScopeSpec EmptySS; 280 TemplateTy TemplateResult; 281 bool MemberOfUnknownSpecialization; 282 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 283 Name, ParsedType(), true, TemplateResult, 284 MemberOfUnknownSpecialization) == TNK_Type_template) { 285 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 286 Diag(IILoc, diag::err_template_missing_args) << TplName; 287 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 288 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 289 << TplDecl->getTemplateParameters()->getSourceRange(); 290 } 291 return true; 292 } 293 } 294 295 // FIXME: Should we move the logic that tries to recover from a missing tag 296 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 297 298 if (!SS || (!SS->isSet() && !SS->isInvalid())) 299 Diag(IILoc, diag::err_unknown_typename) << &II; 300 else if (DeclContext *DC = computeDeclContext(*SS, false)) 301 Diag(IILoc, diag::err_typename_nested_not_found) 302 << &II << DC << SS->getRange(); 303 else if (isDependentScopeSpecifier(*SS)) { 304 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 305 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 306 << SourceRange(SS->getRange().getBegin(), IILoc) 307 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 308 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 309 } else { 310 assert(SS && SS->isInvalid() && 311 "Invalid scope specifier has already been diagnosed"); 312 } 313 314 return true; 315} 316 317// Determines the context to return to after temporarily entering a 318// context. This depends in an unnecessarily complicated way on the 319// exact ordering of callbacks from the parser. 320DeclContext *Sema::getContainingDC(DeclContext *DC) { 321 322 // Functions defined inline within classes aren't parsed until we've 323 // finished parsing the top-level class, so the top-level class is 324 // the context we'll need to return to. 325 if (isa<FunctionDecl>(DC)) { 326 DC = DC->getLexicalParent(); 327 328 // A function not defined within a class will always return to its 329 // lexical context. 330 if (!isa<CXXRecordDecl>(DC)) 331 return DC; 332 333 // A C++ inline method/friend is parsed *after* the topmost class 334 // it was declared in is fully parsed ("complete"); the topmost 335 // class is the context we need to return to. 336 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 337 DC = RD; 338 339 // Return the declaration context of the topmost class the inline method is 340 // declared in. 341 return DC; 342 } 343 344 // ObjCMethodDecls are parsed (for some reason) outside the context 345 // of the class. 346 if (isa<ObjCMethodDecl>(DC)) 347 return DC->getLexicalParent()->getLexicalParent(); 348 349 return DC->getLexicalParent(); 350} 351 352void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 353 assert(getContainingDC(DC) == CurContext && 354 "The next DeclContext should be lexically contained in the current one."); 355 CurContext = DC; 356 S->setEntity(DC); 357} 358 359void Sema::PopDeclContext() { 360 assert(CurContext && "DeclContext imbalance!"); 361 362 CurContext = getContainingDC(CurContext); 363 assert(CurContext && "Popped translation unit!"); 364} 365 366/// EnterDeclaratorContext - Used when we must lookup names in the context 367/// of a declarator's nested name specifier. 368/// 369void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 370 // C++0x [basic.lookup.unqual]p13: 371 // A name used in the definition of a static data member of class 372 // X (after the qualified-id of the static member) is looked up as 373 // if the name was used in a member function of X. 374 // C++0x [basic.lookup.unqual]p14: 375 // If a variable member of a namespace is defined outside of the 376 // scope of its namespace then any name used in the definition of 377 // the variable member (after the declarator-id) is looked up as 378 // if the definition of the variable member occurred in its 379 // namespace. 380 // Both of these imply that we should push a scope whose context 381 // is the semantic context of the declaration. We can't use 382 // PushDeclContext here because that context is not necessarily 383 // lexically contained in the current context. Fortunately, 384 // the containing scope should have the appropriate information. 385 386 assert(!S->getEntity() && "scope already has entity"); 387 388#ifndef NDEBUG 389 Scope *Ancestor = S->getParent(); 390 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 391 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 392#endif 393 394 CurContext = DC; 395 S->setEntity(DC); 396} 397 398void Sema::ExitDeclaratorContext(Scope *S) { 399 assert(S->getEntity() == CurContext && "Context imbalance!"); 400 401 // Switch back to the lexical context. The safety of this is 402 // enforced by an assert in EnterDeclaratorContext. 403 Scope *Ancestor = S->getParent(); 404 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 405 CurContext = (DeclContext*) Ancestor->getEntity(); 406 407 // We don't need to do anything with the scope, which is going to 408 // disappear. 409} 410 411/// \brief Determine whether we allow overloading of the function 412/// PrevDecl with another declaration. 413/// 414/// This routine determines whether overloading is possible, not 415/// whether some new function is actually an overload. It will return 416/// true in C++ (where we can always provide overloads) or, as an 417/// extension, in C when the previous function is already an 418/// overloaded function declaration or has the "overloadable" 419/// attribute. 420static bool AllowOverloadingOfFunction(LookupResult &Previous, 421 ASTContext &Context) { 422 if (Context.getLangOptions().CPlusPlus) 423 return true; 424 425 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 426 return true; 427 428 return (Previous.getResultKind() == LookupResult::Found 429 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 430} 431 432/// Add this decl to the scope shadowed decl chains. 433void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 434 // Move up the scope chain until we find the nearest enclosing 435 // non-transparent context. The declaration will be introduced into this 436 // scope. 437 while (S->getEntity() && 438 ((DeclContext *)S->getEntity())->isTransparentContext()) 439 S = S->getParent(); 440 441 // Add scoped declarations into their context, so that they can be 442 // found later. Declarations without a context won't be inserted 443 // into any context. 444 if (AddToContext) 445 CurContext->addDecl(D); 446 447 // Out-of-line definitions shouldn't be pushed into scope in C++. 448 // Out-of-line variable and function definitions shouldn't even in C. 449 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 450 D->isOutOfLine()) 451 return; 452 453 // Template instantiations should also not be pushed into scope. 454 if (isa<FunctionDecl>(D) && 455 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 456 return; 457 458 // If this replaces anything in the current scope, 459 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 460 IEnd = IdResolver.end(); 461 for (; I != IEnd; ++I) { 462 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 463 S->RemoveDecl(*I); 464 IdResolver.RemoveDecl(*I); 465 466 // Should only need to replace one decl. 467 break; 468 } 469 } 470 471 S->AddDecl(D); 472 IdResolver.AddDecl(D); 473} 474 475bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 476 return IdResolver.isDeclInScope(D, Ctx, Context, S); 477} 478 479Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 480 DeclContext *TargetDC = DC->getPrimaryContext(); 481 do { 482 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 483 if (ScopeDC->getPrimaryContext() == TargetDC) 484 return S; 485 } while ((S = S->getParent())); 486 487 return 0; 488} 489 490static bool isOutOfScopePreviousDeclaration(NamedDecl *, 491 DeclContext*, 492 ASTContext&); 493 494/// Filters out lookup results that don't fall within the given scope 495/// as determined by isDeclInScope. 496static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 497 DeclContext *Ctx, Scope *S, 498 bool ConsiderLinkage) { 499 LookupResult::Filter F = R.makeFilter(); 500 while (F.hasNext()) { 501 NamedDecl *D = F.next(); 502 503 if (SemaRef.isDeclInScope(D, Ctx, S)) 504 continue; 505 506 if (ConsiderLinkage && 507 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 508 continue; 509 510 F.erase(); 511 } 512 513 F.done(); 514} 515 516static bool isUsingDecl(NamedDecl *D) { 517 return isa<UsingShadowDecl>(D) || 518 isa<UnresolvedUsingTypenameDecl>(D) || 519 isa<UnresolvedUsingValueDecl>(D); 520} 521 522/// Removes using shadow declarations from the lookup results. 523static void RemoveUsingDecls(LookupResult &R) { 524 LookupResult::Filter F = R.makeFilter(); 525 while (F.hasNext()) 526 if (isUsingDecl(F.next())) 527 F.erase(); 528 529 F.done(); 530} 531 532/// \brief Check for this common pattern: 533/// @code 534/// class S { 535/// S(const S&); // DO NOT IMPLEMENT 536/// void operator=(const S&); // DO NOT IMPLEMENT 537/// }; 538/// @endcode 539static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 540 // FIXME: Should check for private access too but access is set after we get 541 // the decl here. 542 if (D->isThisDeclarationADefinition()) 543 return false; 544 545 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 546 return CD->isCopyConstructor(); 547 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 548 return Method->isCopyAssignmentOperator(); 549 return false; 550} 551 552bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 553 assert(D); 554 555 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 556 return false; 557 558 // Ignore class templates. 559 if (D->getDeclContext()->isDependentContext()) 560 return false; 561 562 // We warn for unused decls internal to the translation unit. 563 if (D->getLinkage() == ExternalLinkage) 564 return false; 565 566 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 567 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 568 return false; 569 570 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 571 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 572 return false; 573 } else { 574 // 'static inline' functions are used in headers; don't warn. 575 if (FD->getStorageClass() == SC_Static && 576 FD->isInlineSpecified()) 577 return false; 578 } 579 580 if (FD->isThisDeclarationADefinition()) 581 return !Context.DeclMustBeEmitted(FD); 582 return true; 583 } 584 585 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 586 if (VD->isStaticDataMember() && 587 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 588 return false; 589 590 if ( VD->isFileVarDecl() && 591 !VD->getType().isConstant(Context)) 592 return !Context.DeclMustBeEmitted(VD); 593 } 594 595 return false; 596 } 597 598 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 599 if (!D) 600 return; 601 602 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 603 const FunctionDecl *First = FD->getFirstDeclaration(); 604 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 605 return; // First should already be in the vector. 606 } 607 608 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 609 const VarDecl *First = VD->getFirstDeclaration(); 610 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 611 return; // First should already be in the vector. 612 } 613 614 if (ShouldWarnIfUnusedFileScopedDecl(D)) 615 UnusedFileScopedDecls.push_back(D); 616 } 617 618static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 619 if (D->isInvalidDecl()) 620 return false; 621 622 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 623 return false; 624 625 // White-list anything that isn't a local variable. 626 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 627 !D->getDeclContext()->isFunctionOrMethod()) 628 return false; 629 630 // Types of valid local variables should be complete, so this should succeed. 631 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 632 633 // White-list anything with an __attribute__((unused)) type. 634 QualType Ty = VD->getType(); 635 636 // Only look at the outermost level of typedef. 637 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 638 if (TT->getDecl()->hasAttr<UnusedAttr>()) 639 return false; 640 } 641 642 // If we failed to complete the type for some reason, or if the type is 643 // dependent, don't diagnose the variable. 644 if (Ty->isIncompleteType() || Ty->isDependentType()) 645 return false; 646 647 if (const TagType *TT = Ty->getAs<TagType>()) { 648 const TagDecl *Tag = TT->getDecl(); 649 if (Tag->hasAttr<UnusedAttr>()) 650 return false; 651 652 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 653 // FIXME: Checking for the presence of a user-declared constructor 654 // isn't completely accurate; we'd prefer to check that the initializer 655 // has no side effects. 656 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 657 return false; 658 } 659 } 660 661 // TODO: __attribute__((unused)) templates? 662 } 663 664 return true; 665} 666 667void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 668 if (!ShouldDiagnoseUnusedDecl(D)) 669 return; 670 671 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 672 Diag(D->getLocation(), diag::warn_unused_exception_param) 673 << D->getDeclName(); 674 else 675 Diag(D->getLocation(), diag::warn_unused_variable) 676 << D->getDeclName(); 677} 678 679void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 680 if (S->decl_empty()) return; 681 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 682 "Scope shouldn't contain decls!"); 683 684 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 685 I != E; ++I) { 686 Decl *TmpD = (*I); 687 assert(TmpD && "This decl didn't get pushed??"); 688 689 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 690 NamedDecl *D = cast<NamedDecl>(TmpD); 691 692 if (!D->getDeclName()) continue; 693 694 // Diagnose unused variables in this scope. 695 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 696 DiagnoseUnusedDecl(D); 697 698 // Remove this name from our lexical scope. 699 IdResolver.RemoveDecl(D); 700 } 701} 702 703/// \brief Look for an Objective-C class in the translation unit. 704/// 705/// \param Id The name of the Objective-C class we're looking for. If 706/// typo-correction fixes this name, the Id will be updated 707/// to the fixed name. 708/// 709/// \param IdLoc The location of the name in the translation unit. 710/// 711/// \param TypoCorrection If true, this routine will attempt typo correction 712/// if there is no class with the given name. 713/// 714/// \returns The declaration of the named Objective-C class, or NULL if the 715/// class could not be found. 716ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 717 SourceLocation IdLoc, 718 bool TypoCorrection) { 719 // The third "scope" argument is 0 since we aren't enabling lazy built-in 720 // creation from this context. 721 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 722 723 if (!IDecl && TypoCorrection) { 724 // Perform typo correction at the given location, but only if we 725 // find an Objective-C class name. 726 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 727 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 728 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 729 Diag(IdLoc, diag::err_undef_interface_suggest) 730 << Id << IDecl->getDeclName() 731 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 732 Diag(IDecl->getLocation(), diag::note_previous_decl) 733 << IDecl->getDeclName(); 734 735 Id = IDecl->getIdentifier(); 736 } 737 } 738 739 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 740} 741 742/// getNonFieldDeclScope - Retrieves the innermost scope, starting 743/// from S, where a non-field would be declared. This routine copes 744/// with the difference between C and C++ scoping rules in structs and 745/// unions. For example, the following code is well-formed in C but 746/// ill-formed in C++: 747/// @code 748/// struct S6 { 749/// enum { BAR } e; 750/// }; 751/// 752/// void test_S6() { 753/// struct S6 a; 754/// a.e = BAR; 755/// } 756/// @endcode 757/// For the declaration of BAR, this routine will return a different 758/// scope. The scope S will be the scope of the unnamed enumeration 759/// within S6. In C++, this routine will return the scope associated 760/// with S6, because the enumeration's scope is a transparent 761/// context but structures can contain non-field names. In C, this 762/// routine will return the translation unit scope, since the 763/// enumeration's scope is a transparent context and structures cannot 764/// contain non-field names. 765Scope *Sema::getNonFieldDeclScope(Scope *S) { 766 while (((S->getFlags() & Scope::DeclScope) == 0) || 767 (S->getEntity() && 768 ((DeclContext *)S->getEntity())->isTransparentContext()) || 769 (S->isClassScope() && !getLangOptions().CPlusPlus)) 770 S = S->getParent(); 771 return S; 772} 773 774/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 775/// file scope. lazily create a decl for it. ForRedeclaration is true 776/// if we're creating this built-in in anticipation of redeclaring the 777/// built-in. 778NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 779 Scope *S, bool ForRedeclaration, 780 SourceLocation Loc) { 781 Builtin::ID BID = (Builtin::ID)bid; 782 783 ASTContext::GetBuiltinTypeError Error; 784 QualType R = Context.GetBuiltinType(BID, Error); 785 switch (Error) { 786 case ASTContext::GE_None: 787 // Okay 788 break; 789 790 case ASTContext::GE_Missing_stdio: 791 if (ForRedeclaration) 792 Diag(Loc, diag::err_implicit_decl_requires_stdio) 793 << Context.BuiltinInfo.GetName(BID); 794 return 0; 795 796 case ASTContext::GE_Missing_setjmp: 797 if (ForRedeclaration) 798 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 799 << Context.BuiltinInfo.GetName(BID); 800 return 0; 801 } 802 803 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 804 Diag(Loc, diag::ext_implicit_lib_function_decl) 805 << Context.BuiltinInfo.GetName(BID) 806 << R; 807 if (Context.BuiltinInfo.getHeaderName(BID) && 808 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 809 != Diagnostic::Ignored) 810 Diag(Loc, diag::note_please_include_header) 811 << Context.BuiltinInfo.getHeaderName(BID) 812 << Context.BuiltinInfo.GetName(BID); 813 } 814 815 FunctionDecl *New = FunctionDecl::Create(Context, 816 Context.getTranslationUnitDecl(), 817 Loc, II, R, /*TInfo=*/0, 818 SC_Extern, 819 SC_None, false, 820 /*hasPrototype=*/true); 821 New->setImplicit(); 822 823 // Create Decl objects for each parameter, adding them to the 824 // FunctionDecl. 825 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 826 llvm::SmallVector<ParmVarDecl*, 16> Params; 827 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 828 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 829 FT->getArgType(i), /*TInfo=*/0, 830 SC_None, SC_None, 0)); 831 New->setParams(Params.data(), Params.size()); 832 } 833 834 AddKnownFunctionAttributes(New); 835 836 // TUScope is the translation-unit scope to insert this function into. 837 // FIXME: This is hideous. We need to teach PushOnScopeChains to 838 // relate Scopes to DeclContexts, and probably eliminate CurContext 839 // entirely, but we're not there yet. 840 DeclContext *SavedContext = CurContext; 841 CurContext = Context.getTranslationUnitDecl(); 842 PushOnScopeChains(New, TUScope); 843 CurContext = SavedContext; 844 return New; 845} 846 847/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 848/// same name and scope as a previous declaration 'Old'. Figure out 849/// how to resolve this situation, merging decls or emitting 850/// diagnostics as appropriate. If there was an error, set New to be invalid. 851/// 852void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 853 // If the new decl is known invalid already, don't bother doing any 854 // merging checks. 855 if (New->isInvalidDecl()) return; 856 857 // Allow multiple definitions for ObjC built-in typedefs. 858 // FIXME: Verify the underlying types are equivalent! 859 if (getLangOptions().ObjC1) { 860 const IdentifierInfo *TypeID = New->getIdentifier(); 861 switch (TypeID->getLength()) { 862 default: break; 863 case 2: 864 if (!TypeID->isStr("id")) 865 break; 866 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 867 // Install the built-in type for 'id', ignoring the current definition. 868 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 869 return; 870 case 5: 871 if (!TypeID->isStr("Class")) 872 break; 873 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 874 // Install the built-in type for 'Class', ignoring the current definition. 875 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 876 return; 877 case 3: 878 if (!TypeID->isStr("SEL")) 879 break; 880 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 881 // Install the built-in type for 'SEL', ignoring the current definition. 882 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 883 return; 884 case 8: 885 if (!TypeID->isStr("Protocol")) 886 break; 887 Context.setObjCProtoType(New->getUnderlyingType()); 888 return; 889 } 890 // Fall through - the typedef name was not a builtin type. 891 } 892 893 // Verify the old decl was also a type. 894 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 895 if (!Old) { 896 Diag(New->getLocation(), diag::err_redefinition_different_kind) 897 << New->getDeclName(); 898 899 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 900 if (OldD->getLocation().isValid()) 901 Diag(OldD->getLocation(), diag::note_previous_definition); 902 903 return New->setInvalidDecl(); 904 } 905 906 // If the old declaration is invalid, just give up here. 907 if (Old->isInvalidDecl()) 908 return New->setInvalidDecl(); 909 910 // Determine the "old" type we'll use for checking and diagnostics. 911 QualType OldType; 912 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 913 OldType = OldTypedef->getUnderlyingType(); 914 else 915 OldType = Context.getTypeDeclType(Old); 916 917 // If the typedef types are not identical, reject them in all languages and 918 // with any extensions enabled. 919 920 if (OldType != New->getUnderlyingType() && 921 Context.getCanonicalType(OldType) != 922 Context.getCanonicalType(New->getUnderlyingType())) { 923 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 924 << New->getUnderlyingType() << OldType; 925 if (Old->getLocation().isValid()) 926 Diag(Old->getLocation(), diag::note_previous_definition); 927 return New->setInvalidDecl(); 928 } 929 930 // The types match. Link up the redeclaration chain if the old 931 // declaration was a typedef. 932 // FIXME: this is a potential source of wierdness if the type 933 // spellings don't match exactly. 934 if (isa<TypedefDecl>(Old)) 935 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 936 937 if (getLangOptions().Microsoft) 938 return; 939 940 if (getLangOptions().CPlusPlus) { 941 // C++ [dcl.typedef]p2: 942 // In a given non-class scope, a typedef specifier can be used to 943 // redefine the name of any type declared in that scope to refer 944 // to the type to which it already refers. 945 if (!isa<CXXRecordDecl>(CurContext)) 946 return; 947 948 // C++0x [dcl.typedef]p4: 949 // In a given class scope, a typedef specifier can be used to redefine 950 // any class-name declared in that scope that is not also a typedef-name 951 // to refer to the type to which it already refers. 952 // 953 // This wording came in via DR424, which was a correction to the 954 // wording in DR56, which accidentally banned code like: 955 // 956 // struct S { 957 // typedef struct A { } A; 958 // }; 959 // 960 // in the C++03 standard. We implement the C++0x semantics, which 961 // allow the above but disallow 962 // 963 // struct S { 964 // typedef int I; 965 // typedef int I; 966 // }; 967 // 968 // since that was the intent of DR56. 969 if (!isa<TypedefDecl >(Old)) 970 return; 971 972 Diag(New->getLocation(), diag::err_redefinition) 973 << New->getDeclName(); 974 Diag(Old->getLocation(), diag::note_previous_definition); 975 return New->setInvalidDecl(); 976 } 977 978 // If we have a redefinition of a typedef in C, emit a warning. This warning 979 // is normally mapped to an error, but can be controlled with 980 // -Wtypedef-redefinition. If either the original or the redefinition is 981 // in a system header, don't emit this for compatibility with GCC. 982 if (getDiagnostics().getSuppressSystemWarnings() && 983 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 984 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 985 return; 986 987 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 988 << New->getDeclName(); 989 Diag(Old->getLocation(), diag::note_previous_definition); 990 return; 991} 992 993/// DeclhasAttr - returns true if decl Declaration already has the target 994/// attribute. 995static bool 996DeclHasAttr(const Decl *D, const Attr *A) { 997 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 998 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 999 if ((*i)->getKind() == A->getKind()) { 1000 // FIXME: Don't hardcode this check 1001 if (OA && isa<OwnershipAttr>(*i)) 1002 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1003 return true; 1004 } 1005 1006 return false; 1007} 1008 1009/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1010static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1011 if (!Old->hasAttrs()) 1012 return; 1013 // Ensure that any moving of objects within the allocated map is done before 1014 // we process them. 1015 if (!New->hasAttrs()) 1016 New->setAttrs(AttrVec()); 1017 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1018 ++i) { 1019 // FIXME: Make this more general than just checking for Overloadable. 1020 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1021 Attr *NewAttr = (*i)->clone(C); 1022 NewAttr->setInherited(true); 1023 New->addAttr(NewAttr); 1024 } 1025 } 1026} 1027 1028namespace { 1029 1030/// Used in MergeFunctionDecl to keep track of function parameters in 1031/// C. 1032struct GNUCompatibleParamWarning { 1033 ParmVarDecl *OldParm; 1034 ParmVarDecl *NewParm; 1035 QualType PromotedType; 1036}; 1037 1038} 1039 1040/// getSpecialMember - get the special member enum for a method. 1041Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1042 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1043 if (Ctor->isCopyConstructor()) 1044 return Sema::CXXCopyConstructor; 1045 1046 return Sema::CXXConstructor; 1047 } 1048 1049 if (isa<CXXDestructorDecl>(MD)) 1050 return Sema::CXXDestructor; 1051 1052 assert(MD->isCopyAssignmentOperator() && 1053 "Must have copy assignment operator"); 1054 return Sema::CXXCopyAssignment; 1055} 1056 1057/// canRedefineFunction - checks if a function can be redefined. Currently, 1058/// only extern inline functions can be redefined, and even then only in 1059/// GNU89 mode. 1060static bool canRedefineFunction(const FunctionDecl *FD, 1061 const LangOptions& LangOpts) { 1062 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1063 FD->isInlineSpecified() && 1064 FD->getStorageClass() == SC_Extern); 1065} 1066 1067/// MergeFunctionDecl - We just parsed a function 'New' from 1068/// declarator D which has the same name and scope as a previous 1069/// declaration 'Old'. Figure out how to resolve this situation, 1070/// merging decls or emitting diagnostics as appropriate. 1071/// 1072/// In C++, New and Old must be declarations that are not 1073/// overloaded. Use IsOverload to determine whether New and Old are 1074/// overloaded, and to select the Old declaration that New should be 1075/// merged with. 1076/// 1077/// Returns true if there was an error, false otherwise. 1078bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1079 // Verify the old decl was also a function. 1080 FunctionDecl *Old = 0; 1081 if (FunctionTemplateDecl *OldFunctionTemplate 1082 = dyn_cast<FunctionTemplateDecl>(OldD)) 1083 Old = OldFunctionTemplate->getTemplatedDecl(); 1084 else 1085 Old = dyn_cast<FunctionDecl>(OldD); 1086 if (!Old) { 1087 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1088 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1089 Diag(Shadow->getTargetDecl()->getLocation(), 1090 diag::note_using_decl_target); 1091 Diag(Shadow->getUsingDecl()->getLocation(), 1092 diag::note_using_decl) << 0; 1093 return true; 1094 } 1095 1096 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1097 << New->getDeclName(); 1098 Diag(OldD->getLocation(), diag::note_previous_definition); 1099 return true; 1100 } 1101 1102 // Determine whether the previous declaration was a definition, 1103 // implicit declaration, or a declaration. 1104 diag::kind PrevDiag; 1105 if (Old->isThisDeclarationADefinition()) 1106 PrevDiag = diag::note_previous_definition; 1107 else if (Old->isImplicit()) 1108 PrevDiag = diag::note_previous_implicit_declaration; 1109 else 1110 PrevDiag = diag::note_previous_declaration; 1111 1112 QualType OldQType = Context.getCanonicalType(Old->getType()); 1113 QualType NewQType = Context.getCanonicalType(New->getType()); 1114 1115 // Don't complain about this if we're in GNU89 mode and the old function 1116 // is an extern inline function. 1117 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1118 New->getStorageClass() == SC_Static && 1119 Old->getStorageClass() != SC_Static && 1120 !canRedefineFunction(Old, getLangOptions())) { 1121 Diag(New->getLocation(), diag::err_static_non_static) 1122 << New; 1123 Diag(Old->getLocation(), PrevDiag); 1124 return true; 1125 } 1126 1127 // If a function is first declared with a calling convention, but is 1128 // later declared or defined without one, the second decl assumes the 1129 // calling convention of the first. 1130 // 1131 // For the new decl, we have to look at the NON-canonical type to tell the 1132 // difference between a function that really doesn't have a calling 1133 // convention and one that is declared cdecl. That's because in 1134 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1135 // because it is the default calling convention. 1136 // 1137 // Note also that we DO NOT return at this point, because we still have 1138 // other tests to run. 1139 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1140 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1141 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1142 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1143 if (OldTypeInfo.getCC() != CC_Default && 1144 NewTypeInfo.getCC() == CC_Default) { 1145 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1146 New->setType(NewQType); 1147 NewQType = Context.getCanonicalType(NewQType); 1148 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1149 NewTypeInfo.getCC())) { 1150 // Calling conventions really aren't compatible, so complain. 1151 Diag(New->getLocation(), diag::err_cconv_change) 1152 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1153 << (OldTypeInfo.getCC() == CC_Default) 1154 << (OldTypeInfo.getCC() == CC_Default ? "" : 1155 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1156 Diag(Old->getLocation(), diag::note_previous_declaration); 1157 return true; 1158 } 1159 1160 // FIXME: diagnose the other way around? 1161 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1162 NewQType = Context.getNoReturnType(NewQType); 1163 New->setType(NewQType); 1164 assert(NewQType.isCanonical()); 1165 } 1166 1167 // Merge regparm attribute. 1168 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1169 if (NewType->getRegParmType()) { 1170 Diag(New->getLocation(), diag::err_regparm_mismatch) 1171 << NewType->getRegParmType() 1172 << OldType->getRegParmType(); 1173 Diag(Old->getLocation(), diag::note_previous_declaration); 1174 return true; 1175 } 1176 1177 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1178 New->setType(NewQType); 1179 assert(NewQType.isCanonical()); 1180 } 1181 1182 if (getLangOptions().CPlusPlus) { 1183 // (C++98 13.1p2): 1184 // Certain function declarations cannot be overloaded: 1185 // -- Function declarations that differ only in the return type 1186 // cannot be overloaded. 1187 QualType OldReturnType 1188 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1189 QualType NewReturnType 1190 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1191 QualType ResQT; 1192 if (OldReturnType != NewReturnType) { 1193 if (NewReturnType->isObjCObjectPointerType() 1194 && OldReturnType->isObjCObjectPointerType()) 1195 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1196 if (ResQT.isNull()) { 1197 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1198 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1199 return true; 1200 } 1201 else 1202 NewQType = ResQT; 1203 } 1204 1205 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1206 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1207 if (OldMethod && NewMethod) { 1208 // Preserve triviality. 1209 NewMethod->setTrivial(OldMethod->isTrivial()); 1210 1211 bool isFriend = NewMethod->getFriendObjectKind(); 1212 1213 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1214 // -- Member function declarations with the same name and the 1215 // same parameter types cannot be overloaded if any of them 1216 // is a static member function declaration. 1217 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1218 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1219 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1220 return true; 1221 } 1222 1223 // C++ [class.mem]p1: 1224 // [...] A member shall not be declared twice in the 1225 // member-specification, except that a nested class or member 1226 // class template can be declared and then later defined. 1227 unsigned NewDiag; 1228 if (isa<CXXConstructorDecl>(OldMethod)) 1229 NewDiag = diag::err_constructor_redeclared; 1230 else if (isa<CXXDestructorDecl>(NewMethod)) 1231 NewDiag = diag::err_destructor_redeclared; 1232 else if (isa<CXXConversionDecl>(NewMethod)) 1233 NewDiag = diag::err_conv_function_redeclared; 1234 else 1235 NewDiag = diag::err_member_redeclared; 1236 1237 Diag(New->getLocation(), NewDiag); 1238 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1239 1240 // Complain if this is an explicit declaration of a special 1241 // member that was initially declared implicitly. 1242 // 1243 // As an exception, it's okay to befriend such methods in order 1244 // to permit the implicit constructor/destructor/operator calls. 1245 } else if (OldMethod->isImplicit()) { 1246 if (isFriend) { 1247 NewMethod->setImplicit(); 1248 } else { 1249 Diag(NewMethod->getLocation(), 1250 diag::err_definition_of_implicitly_declared_member) 1251 << New << getSpecialMember(OldMethod); 1252 return true; 1253 } 1254 } 1255 } 1256 1257 // (C++98 8.3.5p3): 1258 // All declarations for a function shall agree exactly in both the 1259 // return type and the parameter-type-list. 1260 // attributes should be ignored when comparing. 1261 if (Context.getNoReturnType(OldQType, false) == 1262 Context.getNoReturnType(NewQType, false)) 1263 return MergeCompatibleFunctionDecls(New, Old); 1264 1265 // Fall through for conflicting redeclarations and redefinitions. 1266 } 1267 1268 // C: Function types need to be compatible, not identical. This handles 1269 // duplicate function decls like "void f(int); void f(enum X);" properly. 1270 if (!getLangOptions().CPlusPlus && 1271 Context.typesAreCompatible(OldQType, NewQType)) { 1272 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1273 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1274 const FunctionProtoType *OldProto = 0; 1275 if (isa<FunctionNoProtoType>(NewFuncType) && 1276 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1277 // The old declaration provided a function prototype, but the 1278 // new declaration does not. Merge in the prototype. 1279 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1280 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1281 OldProto->arg_type_end()); 1282 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1283 ParamTypes.data(), ParamTypes.size(), 1284 OldProto->isVariadic(), 1285 OldProto->getTypeQuals(), 1286 false, false, 0, 0, 1287 OldProto->getExtInfo()); 1288 New->setType(NewQType); 1289 New->setHasInheritedPrototype(); 1290 1291 // Synthesize a parameter for each argument type. 1292 llvm::SmallVector<ParmVarDecl*, 16> Params; 1293 for (FunctionProtoType::arg_type_iterator 1294 ParamType = OldProto->arg_type_begin(), 1295 ParamEnd = OldProto->arg_type_end(); 1296 ParamType != ParamEnd; ++ParamType) { 1297 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1298 SourceLocation(), 0, 1299 *ParamType, /*TInfo=*/0, 1300 SC_None, SC_None, 1301 0); 1302 Param->setImplicit(); 1303 Params.push_back(Param); 1304 } 1305 1306 New->setParams(Params.data(), Params.size()); 1307 } 1308 1309 return MergeCompatibleFunctionDecls(New, Old); 1310 } 1311 1312 // GNU C permits a K&R definition to follow a prototype declaration 1313 // if the declared types of the parameters in the K&R definition 1314 // match the types in the prototype declaration, even when the 1315 // promoted types of the parameters from the K&R definition differ 1316 // from the types in the prototype. GCC then keeps the types from 1317 // the prototype. 1318 // 1319 // If a variadic prototype is followed by a non-variadic K&R definition, 1320 // the K&R definition becomes variadic. This is sort of an edge case, but 1321 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1322 // C99 6.9.1p8. 1323 if (!getLangOptions().CPlusPlus && 1324 Old->hasPrototype() && !New->hasPrototype() && 1325 New->getType()->getAs<FunctionProtoType>() && 1326 Old->getNumParams() == New->getNumParams()) { 1327 llvm::SmallVector<QualType, 16> ArgTypes; 1328 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1329 const FunctionProtoType *OldProto 1330 = Old->getType()->getAs<FunctionProtoType>(); 1331 const FunctionProtoType *NewProto 1332 = New->getType()->getAs<FunctionProtoType>(); 1333 1334 // Determine whether this is the GNU C extension. 1335 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1336 NewProto->getResultType()); 1337 bool LooseCompatible = !MergedReturn.isNull(); 1338 for (unsigned Idx = 0, End = Old->getNumParams(); 1339 LooseCompatible && Idx != End; ++Idx) { 1340 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1341 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1342 if (Context.typesAreCompatible(OldParm->getType(), 1343 NewProto->getArgType(Idx))) { 1344 ArgTypes.push_back(NewParm->getType()); 1345 } else if (Context.typesAreCompatible(OldParm->getType(), 1346 NewParm->getType(), 1347 /*CompareUnqualified=*/true)) { 1348 GNUCompatibleParamWarning Warn 1349 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1350 Warnings.push_back(Warn); 1351 ArgTypes.push_back(NewParm->getType()); 1352 } else 1353 LooseCompatible = false; 1354 } 1355 1356 if (LooseCompatible) { 1357 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1358 Diag(Warnings[Warn].NewParm->getLocation(), 1359 diag::ext_param_promoted_not_compatible_with_prototype) 1360 << Warnings[Warn].PromotedType 1361 << Warnings[Warn].OldParm->getType(); 1362 if (Warnings[Warn].OldParm->getLocation().isValid()) 1363 Diag(Warnings[Warn].OldParm->getLocation(), 1364 diag::note_previous_declaration); 1365 } 1366 1367 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1368 ArgTypes.size(), 1369 OldProto->isVariadic(), 0, 1370 false, false, 0, 0, 1371 OldProto->getExtInfo())); 1372 return MergeCompatibleFunctionDecls(New, Old); 1373 } 1374 1375 // Fall through to diagnose conflicting types. 1376 } 1377 1378 // A function that has already been declared has been redeclared or defined 1379 // with a different type- show appropriate diagnostic 1380 if (unsigned BuiltinID = Old->getBuiltinID()) { 1381 // The user has declared a builtin function with an incompatible 1382 // signature. 1383 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1384 // The function the user is redeclaring is a library-defined 1385 // function like 'malloc' or 'printf'. Warn about the 1386 // redeclaration, then pretend that we don't know about this 1387 // library built-in. 1388 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1389 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1390 << Old << Old->getType(); 1391 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1392 Old->setInvalidDecl(); 1393 return false; 1394 } 1395 1396 PrevDiag = diag::note_previous_builtin_declaration; 1397 } 1398 1399 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1400 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1401 return true; 1402} 1403 1404/// \brief Completes the merge of two function declarations that are 1405/// known to be compatible. 1406/// 1407/// This routine handles the merging of attributes and other 1408/// properties of function declarations form the old declaration to 1409/// the new declaration, once we know that New is in fact a 1410/// redeclaration of Old. 1411/// 1412/// \returns false 1413bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1414 // Merge the attributes 1415 MergeDeclAttributes(New, Old, Context); 1416 1417 // Merge the storage class. 1418 if (Old->getStorageClass() != SC_Extern && 1419 Old->getStorageClass() != SC_None) 1420 New->setStorageClass(Old->getStorageClass()); 1421 1422 // Merge "pure" flag. 1423 if (Old->isPure()) 1424 New->setPure(); 1425 1426 // Merge the "deleted" flag. 1427 if (Old->isDeleted()) 1428 New->setDeleted(); 1429 1430 if (getLangOptions().CPlusPlus) 1431 return MergeCXXFunctionDecl(New, Old); 1432 1433 return false; 1434} 1435 1436/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1437/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1438/// situation, merging decls or emitting diagnostics as appropriate. 1439/// 1440/// Tentative definition rules (C99 6.9.2p2) are checked by 1441/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1442/// definitions here, since the initializer hasn't been attached. 1443/// 1444void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1445 // If the new decl is already invalid, don't do any other checking. 1446 if (New->isInvalidDecl()) 1447 return; 1448 1449 // Verify the old decl was also a variable. 1450 VarDecl *Old = 0; 1451 if (!Previous.isSingleResult() || 1452 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1453 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1454 << New->getDeclName(); 1455 Diag(Previous.getRepresentativeDecl()->getLocation(), 1456 diag::note_previous_definition); 1457 return New->setInvalidDecl(); 1458 } 1459 1460 // C++ [class.mem]p1: 1461 // A member shall not be declared twice in the member-specification [...] 1462 // 1463 // Here, we need only consider static data members. 1464 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1465 Diag(New->getLocation(), diag::err_duplicate_member) 1466 << New->getIdentifier(); 1467 Diag(Old->getLocation(), diag::note_previous_declaration); 1468 New->setInvalidDecl(); 1469 } 1470 1471 MergeDeclAttributes(New, Old, Context); 1472 1473 // Merge the types 1474 QualType MergedT; 1475 if (getLangOptions().CPlusPlus) { 1476 if (Context.hasSameType(New->getType(), Old->getType())) 1477 MergedT = New->getType(); 1478 // C++ [basic.link]p10: 1479 // [...] the types specified by all declarations referring to a given 1480 // object or function shall be identical, except that declarations for an 1481 // array object can specify array types that differ by the presence or 1482 // absence of a major array bound (8.3.4). 1483 else if (Old->getType()->isIncompleteArrayType() && 1484 New->getType()->isArrayType()) { 1485 CanQual<ArrayType> OldArray 1486 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1487 CanQual<ArrayType> NewArray 1488 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1489 if (OldArray->getElementType() == NewArray->getElementType()) 1490 MergedT = New->getType(); 1491 } else if (Old->getType()->isArrayType() && 1492 New->getType()->isIncompleteArrayType()) { 1493 CanQual<ArrayType> OldArray 1494 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1495 CanQual<ArrayType> NewArray 1496 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1497 if (OldArray->getElementType() == NewArray->getElementType()) 1498 MergedT = Old->getType(); 1499 } else if (New->getType()->isObjCObjectPointerType() 1500 && Old->getType()->isObjCObjectPointerType()) { 1501 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1502 } 1503 } else { 1504 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1505 } 1506 if (MergedT.isNull()) { 1507 Diag(New->getLocation(), diag::err_redefinition_different_type) 1508 << New->getDeclName(); 1509 Diag(Old->getLocation(), diag::note_previous_definition); 1510 return New->setInvalidDecl(); 1511 } 1512 New->setType(MergedT); 1513 1514 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1515 if (New->getStorageClass() == SC_Static && 1516 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1517 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1518 Diag(Old->getLocation(), diag::note_previous_definition); 1519 return New->setInvalidDecl(); 1520 } 1521 // C99 6.2.2p4: 1522 // For an identifier declared with the storage-class specifier 1523 // extern in a scope in which a prior declaration of that 1524 // identifier is visible,23) if the prior declaration specifies 1525 // internal or external linkage, the linkage of the identifier at 1526 // the later declaration is the same as the linkage specified at 1527 // the prior declaration. If no prior declaration is visible, or 1528 // if the prior declaration specifies no linkage, then the 1529 // identifier has external linkage. 1530 if (New->hasExternalStorage() && Old->hasLinkage()) 1531 /* Okay */; 1532 else if (New->getStorageClass() != SC_Static && 1533 Old->getStorageClass() == SC_Static) { 1534 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1535 Diag(Old->getLocation(), diag::note_previous_definition); 1536 return New->setInvalidDecl(); 1537 } 1538 1539 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1540 1541 // FIXME: The test for external storage here seems wrong? We still 1542 // need to check for mismatches. 1543 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1544 // Don't complain about out-of-line definitions of static members. 1545 !(Old->getLexicalDeclContext()->isRecord() && 1546 !New->getLexicalDeclContext()->isRecord())) { 1547 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1548 Diag(Old->getLocation(), diag::note_previous_definition); 1549 return New->setInvalidDecl(); 1550 } 1551 1552 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1553 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1554 Diag(Old->getLocation(), diag::note_previous_definition); 1555 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1556 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1557 Diag(Old->getLocation(), diag::note_previous_definition); 1558 } 1559 1560 // C++ doesn't have tentative definitions, so go right ahead and check here. 1561 const VarDecl *Def; 1562 if (getLangOptions().CPlusPlus && 1563 New->isThisDeclarationADefinition() == VarDecl::Definition && 1564 (Def = Old->getDefinition())) { 1565 Diag(New->getLocation(), diag::err_redefinition) 1566 << New->getDeclName(); 1567 Diag(Def->getLocation(), diag::note_previous_definition); 1568 New->setInvalidDecl(); 1569 return; 1570 } 1571 // c99 6.2.2 P4. 1572 // For an identifier declared with the storage-class specifier extern in a 1573 // scope in which a prior declaration of that identifier is visible, if 1574 // the prior declaration specifies internal or external linkage, the linkage 1575 // of the identifier at the later declaration is the same as the linkage 1576 // specified at the prior declaration. 1577 // FIXME. revisit this code. 1578 if (New->hasExternalStorage() && 1579 Old->getLinkage() == InternalLinkage && 1580 New->getDeclContext() == Old->getDeclContext()) 1581 New->setStorageClass(Old->getStorageClass()); 1582 1583 // Keep a chain of previous declarations. 1584 New->setPreviousDeclaration(Old); 1585 1586 // Inherit access appropriately. 1587 New->setAccess(Old->getAccess()); 1588} 1589 1590/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1591/// no declarator (e.g. "struct foo;") is parsed. 1592Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1593 DeclSpec &DS) { 1594 // FIXME: Error on inline/virtual/explicit 1595 // FIXME: Warn on useless __thread 1596 // FIXME: Warn on useless const/volatile 1597 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1598 // FIXME: Warn on useless attributes 1599 Decl *TagD = 0; 1600 TagDecl *Tag = 0; 1601 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1602 DS.getTypeSpecType() == DeclSpec::TST_struct || 1603 DS.getTypeSpecType() == DeclSpec::TST_union || 1604 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1605 TagD = DS.getRepAsDecl(); 1606 1607 if (!TagD) // We probably had an error 1608 return 0; 1609 1610 // Note that the above type specs guarantee that the 1611 // type rep is a Decl, whereas in many of the others 1612 // it's a Type. 1613 Tag = dyn_cast<TagDecl>(TagD); 1614 } 1615 1616 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1617 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1618 // or incomplete types shall not be restrict-qualified." 1619 if (TypeQuals & DeclSpec::TQ_restrict) 1620 Diag(DS.getRestrictSpecLoc(), 1621 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1622 << DS.getSourceRange(); 1623 } 1624 1625 if (DS.isFriendSpecified()) { 1626 // If we're dealing with a class template decl, assume that the 1627 // template routines are handling it. 1628 if (TagD && isa<ClassTemplateDecl>(TagD)) 1629 return 0; 1630 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1631 } 1632 1633 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1634 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1635 1636 if (!Record->getDeclName() && Record->isDefinition() && 1637 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1638 if (getLangOptions().CPlusPlus || 1639 Record->getDeclContext()->isRecord()) 1640 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1641 1642 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1643 << DS.getSourceRange(); 1644 } 1645 1646 // Microsoft allows unnamed struct/union fields. Don't complain 1647 // about them. 1648 // FIXME: Should we support Microsoft's extensions in this area? 1649 if (Record->getDeclName() && getLangOptions().Microsoft) 1650 return Tag; 1651 } 1652 1653 if (getLangOptions().CPlusPlus && 1654 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1655 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1656 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1657 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1658 Diag(Enum->getLocation(), diag::ext_no_declarators) 1659 << DS.getSourceRange(); 1660 1661 if (!DS.isMissingDeclaratorOk() && 1662 DS.getTypeSpecType() != DeclSpec::TST_error) { 1663 // Warn about typedefs of enums without names, since this is an 1664 // extension in both Microsoft and GNU. 1665 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1666 Tag && isa<EnumDecl>(Tag)) { 1667 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1668 << DS.getSourceRange(); 1669 return Tag; 1670 } 1671 1672 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1673 << DS.getSourceRange(); 1674 } 1675 1676 return TagD; 1677} 1678 1679/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1680/// builds a statement for it and returns it so it is evaluated. 1681StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1682 StmtResult R; 1683 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1684 Expr *Exp = DS.getRepAsExpr(); 1685 QualType Ty = Exp->getType(); 1686 if (Ty->isPointerType()) { 1687 do 1688 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1689 while (Ty->isPointerType()); 1690 } 1691 if (Ty->isVariableArrayType()) { 1692 R = ActOnExprStmt(MakeFullExpr(Exp)); 1693 } 1694 } 1695 return R; 1696} 1697 1698/// We are trying to inject an anonymous member into the given scope; 1699/// check if there's an existing declaration that can't be overloaded. 1700/// 1701/// \return true if this is a forbidden redeclaration 1702static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1703 Scope *S, 1704 DeclContext *Owner, 1705 DeclarationName Name, 1706 SourceLocation NameLoc, 1707 unsigned diagnostic) { 1708 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1709 Sema::ForRedeclaration); 1710 if (!SemaRef.LookupName(R, S)) return false; 1711 1712 if (R.getAsSingle<TagDecl>()) 1713 return false; 1714 1715 // Pick a representative declaration. 1716 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1717 assert(PrevDecl && "Expected a non-null Decl"); 1718 1719 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1720 return false; 1721 1722 SemaRef.Diag(NameLoc, diagnostic) << Name; 1723 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1724 1725 return true; 1726} 1727 1728/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1729/// anonymous struct or union AnonRecord into the owning context Owner 1730/// and scope S. This routine will be invoked just after we realize 1731/// that an unnamed union or struct is actually an anonymous union or 1732/// struct, e.g., 1733/// 1734/// @code 1735/// union { 1736/// int i; 1737/// float f; 1738/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1739/// // f into the surrounding scope.x 1740/// @endcode 1741/// 1742/// This routine is recursive, injecting the names of nested anonymous 1743/// structs/unions into the owning context and scope as well. 1744static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1745 DeclContext *Owner, 1746 RecordDecl *AnonRecord, 1747 AccessSpecifier AS) { 1748 unsigned diagKind 1749 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1750 : diag::err_anonymous_struct_member_redecl; 1751 1752 bool Invalid = false; 1753 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1754 FEnd = AnonRecord->field_end(); 1755 F != FEnd; ++F) { 1756 if ((*F)->getDeclName()) { 1757 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1758 (*F)->getLocation(), diagKind)) { 1759 // C++ [class.union]p2: 1760 // The names of the members of an anonymous union shall be 1761 // distinct from the names of any other entity in the 1762 // scope in which the anonymous union is declared. 1763 Invalid = true; 1764 } else { 1765 // C++ [class.union]p2: 1766 // For the purpose of name lookup, after the anonymous union 1767 // definition, the members of the anonymous union are 1768 // considered to have been defined in the scope in which the 1769 // anonymous union is declared. 1770 Owner->makeDeclVisibleInContext(*F); 1771 S->AddDecl(*F); 1772 SemaRef.IdResolver.AddDecl(*F); 1773 1774 // That includes picking up the appropriate access specifier. 1775 if (AS != AS_none) (*F)->setAccess(AS); 1776 } 1777 } else if (const RecordType *InnerRecordType 1778 = (*F)->getType()->getAs<RecordType>()) { 1779 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1780 if (InnerRecord->isAnonymousStructOrUnion()) 1781 Invalid = Invalid || 1782 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1783 InnerRecord, AS); 1784 } 1785 } 1786 1787 return Invalid; 1788} 1789 1790/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1791/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1792/// illegal input values are mapped to SC_None. 1793static StorageClass 1794StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1795 switch (StorageClassSpec) { 1796 case DeclSpec::SCS_unspecified: return SC_None; 1797 case DeclSpec::SCS_extern: return SC_Extern; 1798 case DeclSpec::SCS_static: return SC_Static; 1799 case DeclSpec::SCS_auto: return SC_Auto; 1800 case DeclSpec::SCS_register: return SC_Register; 1801 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1802 // Illegal SCSs map to None: error reporting is up to the caller. 1803 case DeclSpec::SCS_mutable: // Fall through. 1804 case DeclSpec::SCS_typedef: return SC_None; 1805 } 1806 llvm_unreachable("unknown storage class specifier"); 1807} 1808 1809/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1810/// a StorageClass. Any error reporting is up to the caller: 1811/// illegal input values are mapped to SC_None. 1812static StorageClass 1813StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1814 switch (StorageClassSpec) { 1815 case DeclSpec::SCS_unspecified: return SC_None; 1816 case DeclSpec::SCS_extern: return SC_Extern; 1817 case DeclSpec::SCS_static: return SC_Static; 1818 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1819 // Illegal SCSs map to None: error reporting is up to the caller. 1820 case DeclSpec::SCS_auto: // Fall through. 1821 case DeclSpec::SCS_mutable: // Fall through. 1822 case DeclSpec::SCS_register: // Fall through. 1823 case DeclSpec::SCS_typedef: return SC_None; 1824 } 1825 llvm_unreachable("unknown storage class specifier"); 1826} 1827 1828/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1829/// anonymous structure or union. Anonymous unions are a C++ feature 1830/// (C++ [class.union]) and a GNU C extension; anonymous structures 1831/// are a GNU C and GNU C++ extension. 1832Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1833 AccessSpecifier AS, 1834 RecordDecl *Record) { 1835 DeclContext *Owner = Record->getDeclContext(); 1836 1837 // Diagnose whether this anonymous struct/union is an extension. 1838 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1839 Diag(Record->getLocation(), diag::ext_anonymous_union); 1840 else if (!Record->isUnion()) 1841 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1842 1843 // C and C++ require different kinds of checks for anonymous 1844 // structs/unions. 1845 bool Invalid = false; 1846 if (getLangOptions().CPlusPlus) { 1847 const char* PrevSpec = 0; 1848 unsigned DiagID; 1849 // C++ [class.union]p3: 1850 // Anonymous unions declared in a named namespace or in the 1851 // global namespace shall be declared static. 1852 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1853 (isa<TranslationUnitDecl>(Owner) || 1854 (isa<NamespaceDecl>(Owner) && 1855 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1856 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1857 Invalid = true; 1858 1859 // Recover by adding 'static'. 1860 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1861 PrevSpec, DiagID); 1862 } 1863 // C++ [class.union]p3: 1864 // A storage class is not allowed in a declaration of an 1865 // anonymous union in a class scope. 1866 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1867 isa<RecordDecl>(Owner)) { 1868 Diag(DS.getStorageClassSpecLoc(), 1869 diag::err_anonymous_union_with_storage_spec); 1870 Invalid = true; 1871 1872 // Recover by removing the storage specifier. 1873 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1874 PrevSpec, DiagID); 1875 } 1876 1877 // C++ [class.union]p2: 1878 // The member-specification of an anonymous union shall only 1879 // define non-static data members. [Note: nested types and 1880 // functions cannot be declared within an anonymous union. ] 1881 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1882 MemEnd = Record->decls_end(); 1883 Mem != MemEnd; ++Mem) { 1884 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1885 // C++ [class.union]p3: 1886 // An anonymous union shall not have private or protected 1887 // members (clause 11). 1888 assert(FD->getAccess() != AS_none); 1889 if (FD->getAccess() != AS_public) { 1890 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1891 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1892 Invalid = true; 1893 } 1894 1895 if (CheckNontrivialField(FD)) 1896 Invalid = true; 1897 } else if ((*Mem)->isImplicit()) { 1898 // Any implicit members are fine. 1899 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1900 // This is a type that showed up in an 1901 // elaborated-type-specifier inside the anonymous struct or 1902 // union, but which actually declares a type outside of the 1903 // anonymous struct or union. It's okay. 1904 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1905 if (!MemRecord->isAnonymousStructOrUnion() && 1906 MemRecord->getDeclName()) { 1907 // Visual C++ allows type definition in anonymous struct or union. 1908 if (getLangOptions().Microsoft) 1909 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 1910 << (int)Record->isUnion(); 1911 else { 1912 // This is a nested type declaration. 1913 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1914 << (int)Record->isUnion(); 1915 Invalid = true; 1916 } 1917 } 1918 } else if (isa<AccessSpecDecl>(*Mem)) { 1919 // Any access specifier is fine. 1920 } else { 1921 // We have something that isn't a non-static data 1922 // member. Complain about it. 1923 unsigned DK = diag::err_anonymous_record_bad_member; 1924 if (isa<TypeDecl>(*Mem)) 1925 DK = diag::err_anonymous_record_with_type; 1926 else if (isa<FunctionDecl>(*Mem)) 1927 DK = diag::err_anonymous_record_with_function; 1928 else if (isa<VarDecl>(*Mem)) 1929 DK = diag::err_anonymous_record_with_static; 1930 1931 // Visual C++ allows type definition in anonymous struct or union. 1932 if (getLangOptions().Microsoft && 1933 DK == diag::err_anonymous_record_with_type) 1934 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 1935 << (int)Record->isUnion(); 1936 else { 1937 Diag((*Mem)->getLocation(), DK) 1938 << (int)Record->isUnion(); 1939 Invalid = true; 1940 } 1941 } 1942 } 1943 } 1944 1945 if (!Record->isUnion() && !Owner->isRecord()) { 1946 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1947 << (int)getLangOptions().CPlusPlus; 1948 Invalid = true; 1949 } 1950 1951 // Mock up a declarator. 1952 Declarator Dc(DS, Declarator::TypeNameContext); 1953 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1954 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1955 1956 // Create a declaration for this anonymous struct/union. 1957 NamedDecl *Anon = 0; 1958 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1959 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1960 /*IdentifierInfo=*/0, 1961 Context.getTypeDeclType(Record), 1962 TInfo, 1963 /*BitWidth=*/0, /*Mutable=*/false); 1964 Anon->setAccess(AS); 1965 if (getLangOptions().CPlusPlus) 1966 FieldCollector->Add(cast<FieldDecl>(Anon)); 1967 } else { 1968 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1969 assert(SCSpec != DeclSpec::SCS_typedef && 1970 "Parser allowed 'typedef' as storage class VarDecl."); 1971 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1972 if (SCSpec == DeclSpec::SCS_mutable) { 1973 // mutable can only appear on non-static class members, so it's always 1974 // an error here 1975 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1976 Invalid = true; 1977 SC = SC_None; 1978 } 1979 SCSpec = DS.getStorageClassSpecAsWritten(); 1980 VarDecl::StorageClass SCAsWritten 1981 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1982 1983 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1984 /*IdentifierInfo=*/0, 1985 Context.getTypeDeclType(Record), 1986 TInfo, SC, SCAsWritten); 1987 } 1988 Anon->setImplicit(); 1989 1990 // Add the anonymous struct/union object to the current 1991 // context. We'll be referencing this object when we refer to one of 1992 // its members. 1993 Owner->addDecl(Anon); 1994 1995 // Inject the members of the anonymous struct/union into the owning 1996 // context and into the identifier resolver chain for name lookup 1997 // purposes. 1998 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1999 Invalid = true; 2000 2001 // Mark this as an anonymous struct/union type. Note that we do not 2002 // do this until after we have already checked and injected the 2003 // members of this anonymous struct/union type, because otherwise 2004 // the members could be injected twice: once by DeclContext when it 2005 // builds its lookup table, and once by 2006 // InjectAnonymousStructOrUnionMembers. 2007 Record->setAnonymousStructOrUnion(true); 2008 2009 if (Invalid) 2010 Anon->setInvalidDecl(); 2011 2012 return Anon; 2013} 2014 2015 2016/// GetNameForDeclarator - Determine the full declaration name for the 2017/// given Declarator. 2018DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2019 return GetNameFromUnqualifiedId(D.getName()); 2020} 2021 2022/// \brief Retrieves the declaration name from a parsed unqualified-id. 2023DeclarationNameInfo 2024Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2025 DeclarationNameInfo NameInfo; 2026 NameInfo.setLoc(Name.StartLocation); 2027 2028 switch (Name.getKind()) { 2029 2030 case UnqualifiedId::IK_Identifier: 2031 NameInfo.setName(Name.Identifier); 2032 NameInfo.setLoc(Name.StartLocation); 2033 return NameInfo; 2034 2035 case UnqualifiedId::IK_OperatorFunctionId: 2036 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2037 Name.OperatorFunctionId.Operator)); 2038 NameInfo.setLoc(Name.StartLocation); 2039 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2040 = Name.OperatorFunctionId.SymbolLocations[0]; 2041 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2042 = Name.EndLocation.getRawEncoding(); 2043 return NameInfo; 2044 2045 case UnqualifiedId::IK_LiteralOperatorId: 2046 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2047 Name.Identifier)); 2048 NameInfo.setLoc(Name.StartLocation); 2049 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2050 return NameInfo; 2051 2052 case UnqualifiedId::IK_ConversionFunctionId: { 2053 TypeSourceInfo *TInfo; 2054 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2055 if (Ty.isNull()) 2056 return DeclarationNameInfo(); 2057 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2058 Context.getCanonicalType(Ty))); 2059 NameInfo.setLoc(Name.StartLocation); 2060 NameInfo.setNamedTypeInfo(TInfo); 2061 return NameInfo; 2062 } 2063 2064 case UnqualifiedId::IK_ConstructorName: { 2065 TypeSourceInfo *TInfo; 2066 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2067 if (Ty.isNull()) 2068 return DeclarationNameInfo(); 2069 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2070 Context.getCanonicalType(Ty))); 2071 NameInfo.setLoc(Name.StartLocation); 2072 NameInfo.setNamedTypeInfo(TInfo); 2073 return NameInfo; 2074 } 2075 2076 case UnqualifiedId::IK_ConstructorTemplateId: { 2077 // In well-formed code, we can only have a constructor 2078 // template-id that refers to the current context, so go there 2079 // to find the actual type being constructed. 2080 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2081 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2082 return DeclarationNameInfo(); 2083 2084 // Determine the type of the class being constructed. 2085 QualType CurClassType = Context.getTypeDeclType(CurClass); 2086 2087 // FIXME: Check two things: that the template-id names the same type as 2088 // CurClassType, and that the template-id does not occur when the name 2089 // was qualified. 2090 2091 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2092 Context.getCanonicalType(CurClassType))); 2093 NameInfo.setLoc(Name.StartLocation); 2094 // FIXME: should we retrieve TypeSourceInfo? 2095 NameInfo.setNamedTypeInfo(0); 2096 return NameInfo; 2097 } 2098 2099 case UnqualifiedId::IK_DestructorName: { 2100 TypeSourceInfo *TInfo; 2101 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2102 if (Ty.isNull()) 2103 return DeclarationNameInfo(); 2104 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2105 Context.getCanonicalType(Ty))); 2106 NameInfo.setLoc(Name.StartLocation); 2107 NameInfo.setNamedTypeInfo(TInfo); 2108 return NameInfo; 2109 } 2110 2111 case UnqualifiedId::IK_TemplateId: { 2112 TemplateName TName = Name.TemplateId->Template.get(); 2113 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2114 return Context.getNameForTemplate(TName, TNameLoc); 2115 } 2116 2117 } // switch (Name.getKind()) 2118 2119 assert(false && "Unknown name kind"); 2120 return DeclarationNameInfo(); 2121} 2122 2123/// isNearlyMatchingFunction - Determine whether the C++ functions 2124/// Declaration and Definition are "nearly" matching. This heuristic 2125/// is used to improve diagnostics in the case where an out-of-line 2126/// function definition doesn't match any declaration within 2127/// the class or namespace. 2128static bool isNearlyMatchingFunction(ASTContext &Context, 2129 FunctionDecl *Declaration, 2130 FunctionDecl *Definition) { 2131 if (Declaration->param_size() != Definition->param_size()) 2132 return false; 2133 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2134 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2135 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2136 2137 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2138 DefParamTy.getNonReferenceType())) 2139 return false; 2140 } 2141 2142 return true; 2143} 2144 2145/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2146/// declarator needs to be rebuilt in the current instantiation. 2147/// Any bits of declarator which appear before the name are valid for 2148/// consideration here. That's specifically the type in the decl spec 2149/// and the base type in any member-pointer chunks. 2150static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2151 DeclarationName Name) { 2152 // The types we specifically need to rebuild are: 2153 // - typenames, typeofs, and decltypes 2154 // - types which will become injected class names 2155 // Of course, we also need to rebuild any type referencing such a 2156 // type. It's safest to just say "dependent", but we call out a 2157 // few cases here. 2158 2159 DeclSpec &DS = D.getMutableDeclSpec(); 2160 switch (DS.getTypeSpecType()) { 2161 case DeclSpec::TST_typename: 2162 case DeclSpec::TST_typeofType: 2163 case DeclSpec::TST_decltype: { 2164 // Grab the type from the parser. 2165 TypeSourceInfo *TSI = 0; 2166 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2167 if (T.isNull() || !T->isDependentType()) break; 2168 2169 // Make sure there's a type source info. This isn't really much 2170 // of a waste; most dependent types should have type source info 2171 // attached already. 2172 if (!TSI) 2173 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2174 2175 // Rebuild the type in the current instantiation. 2176 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2177 if (!TSI) return true; 2178 2179 // Store the new type back in the decl spec. 2180 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2181 DS.UpdateTypeRep(LocType); 2182 break; 2183 } 2184 2185 case DeclSpec::TST_typeofExpr: { 2186 Expr *E = DS.getRepAsExpr(); 2187 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2188 if (Result.isInvalid()) return true; 2189 DS.UpdateExprRep(Result.get()); 2190 break; 2191 } 2192 2193 default: 2194 // Nothing to do for these decl specs. 2195 break; 2196 } 2197 2198 // It doesn't matter what order we do this in. 2199 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2200 DeclaratorChunk &Chunk = D.getTypeObject(I); 2201 2202 // The only type information in the declarator which can come 2203 // before the declaration name is the base type of a member 2204 // pointer. 2205 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2206 continue; 2207 2208 // Rebuild the scope specifier in-place. 2209 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2210 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2211 return true; 2212 } 2213 2214 return false; 2215} 2216 2217Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2218 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2219} 2220 2221Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2222 MultiTemplateParamsArg TemplateParamLists, 2223 bool IsFunctionDefinition) { 2224 // TODO: consider using NameInfo for diagnostic. 2225 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2226 DeclarationName Name = NameInfo.getName(); 2227 2228 // All of these full declarators require an identifier. If it doesn't have 2229 // one, the ParsedFreeStandingDeclSpec action should be used. 2230 if (!Name) { 2231 if (!D.isInvalidType()) // Reject this if we think it is valid. 2232 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2233 diag::err_declarator_need_ident) 2234 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2235 return 0; 2236 } 2237 2238 // The scope passed in may not be a decl scope. Zip up the scope tree until 2239 // we find one that is. 2240 while ((S->getFlags() & Scope::DeclScope) == 0 || 2241 (S->getFlags() & Scope::TemplateParamScope) != 0) 2242 S = S->getParent(); 2243 2244 DeclContext *DC = CurContext; 2245 if (D.getCXXScopeSpec().isInvalid()) 2246 D.setInvalidType(); 2247 else if (D.getCXXScopeSpec().isSet()) { 2248 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2249 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2250 if (!DC) { 2251 // If we could not compute the declaration context, it's because the 2252 // declaration context is dependent but does not refer to a class, 2253 // class template, or class template partial specialization. Complain 2254 // and return early, to avoid the coming semantic disaster. 2255 Diag(D.getIdentifierLoc(), 2256 diag::err_template_qualified_declarator_no_match) 2257 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2258 << D.getCXXScopeSpec().getRange(); 2259 return 0; 2260 } 2261 2262 bool IsDependentContext = DC->isDependentContext(); 2263 2264 if (!IsDependentContext && 2265 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2266 return 0; 2267 2268 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2269 Diag(D.getIdentifierLoc(), 2270 diag::err_member_def_undefined_record) 2271 << Name << DC << D.getCXXScopeSpec().getRange(); 2272 D.setInvalidType(); 2273 } 2274 2275 // Check whether we need to rebuild the type of the given 2276 // declaration in the current instantiation. 2277 if (EnteringContext && IsDependentContext && 2278 TemplateParamLists.size() != 0) { 2279 ContextRAII SavedContext(*this, DC); 2280 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2281 D.setInvalidType(); 2282 } 2283 } 2284 2285 NamedDecl *New; 2286 2287 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2288 QualType R = TInfo->getType(); 2289 2290 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2291 ForRedeclaration); 2292 2293 // See if this is a redefinition of a variable in the same scope. 2294 if (!D.getCXXScopeSpec().isSet()) { 2295 bool IsLinkageLookup = false; 2296 2297 // If the declaration we're planning to build will be a function 2298 // or object with linkage, then look for another declaration with 2299 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2300 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2301 /* Do nothing*/; 2302 else if (R->isFunctionType()) { 2303 if (CurContext->isFunctionOrMethod() || 2304 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2305 IsLinkageLookup = true; 2306 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2307 IsLinkageLookup = true; 2308 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2309 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2310 IsLinkageLookup = true; 2311 2312 if (IsLinkageLookup) 2313 Previous.clear(LookupRedeclarationWithLinkage); 2314 2315 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2316 } else { // Something like "int foo::x;" 2317 LookupQualifiedName(Previous, DC); 2318 2319 // Don't consider using declarations as previous declarations for 2320 // out-of-line members. 2321 RemoveUsingDecls(Previous); 2322 2323 // C++ 7.3.1.2p2: 2324 // Members (including explicit specializations of templates) of a named 2325 // namespace can also be defined outside that namespace by explicit 2326 // qualification of the name being defined, provided that the entity being 2327 // defined was already declared in the namespace and the definition appears 2328 // after the point of declaration in a namespace that encloses the 2329 // declarations namespace. 2330 // 2331 // Note that we only check the context at this point. We don't yet 2332 // have enough information to make sure that PrevDecl is actually 2333 // the declaration we want to match. For example, given: 2334 // 2335 // class X { 2336 // void f(); 2337 // void f(float); 2338 // }; 2339 // 2340 // void X::f(int) { } // ill-formed 2341 // 2342 // In this case, PrevDecl will point to the overload set 2343 // containing the two f's declared in X, but neither of them 2344 // matches. 2345 2346 // First check whether we named the global scope. 2347 if (isa<TranslationUnitDecl>(DC)) { 2348 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2349 << Name << D.getCXXScopeSpec().getRange(); 2350 } else { 2351 DeclContext *Cur = CurContext; 2352 while (isa<LinkageSpecDecl>(Cur)) 2353 Cur = Cur->getParent(); 2354 if (!Cur->Encloses(DC)) { 2355 // The qualifying scope doesn't enclose the original declaration. 2356 // Emit diagnostic based on current scope. 2357 SourceLocation L = D.getIdentifierLoc(); 2358 SourceRange R = D.getCXXScopeSpec().getRange(); 2359 if (isa<FunctionDecl>(Cur)) 2360 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2361 else 2362 Diag(L, diag::err_invalid_declarator_scope) 2363 << Name << cast<NamedDecl>(DC) << R; 2364 D.setInvalidType(); 2365 } 2366 } 2367 } 2368 2369 if (Previous.isSingleResult() && 2370 Previous.getFoundDecl()->isTemplateParameter()) { 2371 // Maybe we will complain about the shadowed template parameter. 2372 if (!D.isInvalidType()) 2373 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2374 Previous.getFoundDecl())) 2375 D.setInvalidType(); 2376 2377 // Just pretend that we didn't see the previous declaration. 2378 Previous.clear(); 2379 } 2380 2381 // In C++, the previous declaration we find might be a tag type 2382 // (class or enum). In this case, the new declaration will hide the 2383 // tag type. Note that this does does not apply if we're declaring a 2384 // typedef (C++ [dcl.typedef]p4). 2385 if (Previous.isSingleTagDecl() && 2386 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2387 Previous.clear(); 2388 2389 bool Redeclaration = false; 2390 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2391 if (TemplateParamLists.size()) { 2392 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2393 return 0; 2394 } 2395 2396 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2397 } else if (R->isFunctionType()) { 2398 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2399 move(TemplateParamLists), 2400 IsFunctionDefinition, Redeclaration); 2401 } else { 2402 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2403 move(TemplateParamLists), 2404 Redeclaration); 2405 } 2406 2407 if (New == 0) 2408 return 0; 2409 2410 // If this has an identifier and is not an invalid redeclaration or 2411 // function template specialization, add it to the scope stack. 2412 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2413 PushOnScopeChains(New, S); 2414 2415 return New; 2416} 2417 2418/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2419/// types into constant array types in certain situations which would otherwise 2420/// be errors (for GCC compatibility). 2421static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2422 ASTContext &Context, 2423 bool &SizeIsNegative, 2424 llvm::APSInt &Oversized) { 2425 // This method tries to turn a variable array into a constant 2426 // array even when the size isn't an ICE. This is necessary 2427 // for compatibility with code that depends on gcc's buggy 2428 // constant expression folding, like struct {char x[(int)(char*)2];} 2429 SizeIsNegative = false; 2430 Oversized = 0; 2431 2432 if (T->isDependentType()) 2433 return QualType(); 2434 2435 QualifierCollector Qs; 2436 const Type *Ty = Qs.strip(T); 2437 2438 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2439 QualType Pointee = PTy->getPointeeType(); 2440 QualType FixedType = 2441 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2442 Oversized); 2443 if (FixedType.isNull()) return FixedType; 2444 FixedType = Context.getPointerType(FixedType); 2445 return Qs.apply(FixedType); 2446 } 2447 2448 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2449 if (!VLATy) 2450 return QualType(); 2451 // FIXME: We should probably handle this case 2452 if (VLATy->getElementType()->isVariablyModifiedType()) 2453 return QualType(); 2454 2455 Expr::EvalResult EvalResult; 2456 if (!VLATy->getSizeExpr() || 2457 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2458 !EvalResult.Val.isInt()) 2459 return QualType(); 2460 2461 // Check whether the array size is negative. 2462 llvm::APSInt &Res = EvalResult.Val.getInt(); 2463 if (Res.isSigned() && Res.isNegative()) { 2464 SizeIsNegative = true; 2465 return QualType(); 2466 } 2467 2468 // Check whether the array is too large to be addressed. 2469 unsigned ActiveSizeBits 2470 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2471 Res); 2472 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2473 Oversized = Res; 2474 return QualType(); 2475 } 2476 2477 return Context.getConstantArrayType(VLATy->getElementType(), 2478 Res, ArrayType::Normal, 0); 2479} 2480 2481/// \brief Register the given locally-scoped external C declaration so 2482/// that it can be found later for redeclarations 2483void 2484Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2485 const LookupResult &Previous, 2486 Scope *S) { 2487 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2488 "Decl is not a locally-scoped decl!"); 2489 // Note that we have a locally-scoped external with this name. 2490 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2491 2492 if (!Previous.isSingleResult()) 2493 return; 2494 2495 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2496 2497 // If there was a previous declaration of this variable, it may be 2498 // in our identifier chain. Update the identifier chain with the new 2499 // declaration. 2500 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2501 // The previous declaration was found on the identifer resolver 2502 // chain, so remove it from its scope. 2503 while (S && !S->isDeclScope(PrevDecl)) 2504 S = S->getParent(); 2505 2506 if (S) 2507 S->RemoveDecl(PrevDecl); 2508 } 2509} 2510 2511/// \brief Diagnose function specifiers on a declaration of an identifier that 2512/// does not identify a function. 2513void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2514 // FIXME: We should probably indicate the identifier in question to avoid 2515 // confusion for constructs like "inline int a(), b;" 2516 if (D.getDeclSpec().isInlineSpecified()) 2517 Diag(D.getDeclSpec().getInlineSpecLoc(), 2518 diag::err_inline_non_function); 2519 2520 if (D.getDeclSpec().isVirtualSpecified()) 2521 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2522 diag::err_virtual_non_function); 2523 2524 if (D.getDeclSpec().isExplicitSpecified()) 2525 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2526 diag::err_explicit_non_function); 2527} 2528 2529NamedDecl* 2530Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2531 QualType R, TypeSourceInfo *TInfo, 2532 LookupResult &Previous, bool &Redeclaration) { 2533 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2534 if (D.getCXXScopeSpec().isSet()) { 2535 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2536 << D.getCXXScopeSpec().getRange(); 2537 D.setInvalidType(); 2538 // Pretend we didn't see the scope specifier. 2539 DC = CurContext; 2540 Previous.clear(); 2541 } 2542 2543 if (getLangOptions().CPlusPlus) { 2544 // Check that there are no default arguments (C++ only). 2545 CheckExtraCXXDefaultArguments(D); 2546 } 2547 2548 DiagnoseFunctionSpecifiers(D); 2549 2550 if (D.getDeclSpec().isThreadSpecified()) 2551 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2552 2553 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2554 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2555 << D.getName().getSourceRange(); 2556 return 0; 2557 } 2558 2559 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2560 if (!NewTD) return 0; 2561 2562 // Handle attributes prior to checking for duplicates in MergeVarDecl 2563 ProcessDeclAttributes(S, NewTD, D); 2564 2565 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2566 // then it shall have block scope. 2567 // Note that variably modified types must be fixed before merging the decl so 2568 // that redeclarations will match. 2569 QualType T = NewTD->getUnderlyingType(); 2570 if (T->isVariablyModifiedType()) { 2571 getCurFunction()->setHasBranchProtectedScope(); 2572 2573 if (S->getFnParent() == 0) { 2574 bool SizeIsNegative; 2575 llvm::APSInt Oversized; 2576 QualType FixedTy = 2577 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2578 Oversized); 2579 if (!FixedTy.isNull()) { 2580 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2581 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2582 } else { 2583 if (SizeIsNegative) 2584 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2585 else if (T->isVariableArrayType()) 2586 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2587 else if (Oversized.getBoolValue()) 2588 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2589 << Oversized.toString(10); 2590 else 2591 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2592 NewTD->setInvalidDecl(); 2593 } 2594 } 2595 } 2596 2597 // Merge the decl with the existing one if appropriate. If the decl is 2598 // in an outer scope, it isn't the same thing. 2599 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2600 if (!Previous.empty()) { 2601 Redeclaration = true; 2602 MergeTypeDefDecl(NewTD, Previous); 2603 } 2604 2605 // If this is the C FILE type, notify the AST context. 2606 if (IdentifierInfo *II = NewTD->getIdentifier()) 2607 if (!NewTD->isInvalidDecl() && 2608 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2609 if (II->isStr("FILE")) 2610 Context.setFILEDecl(NewTD); 2611 else if (II->isStr("jmp_buf")) 2612 Context.setjmp_bufDecl(NewTD); 2613 else if (II->isStr("sigjmp_buf")) 2614 Context.setsigjmp_bufDecl(NewTD); 2615 else if (II->isStr("__builtin_va_list")) 2616 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2617 } 2618 2619 return NewTD; 2620} 2621 2622/// \brief Determines whether the given declaration is an out-of-scope 2623/// previous declaration. 2624/// 2625/// This routine should be invoked when name lookup has found a 2626/// previous declaration (PrevDecl) that is not in the scope where a 2627/// new declaration by the same name is being introduced. If the new 2628/// declaration occurs in a local scope, previous declarations with 2629/// linkage may still be considered previous declarations (C99 2630/// 6.2.2p4-5, C++ [basic.link]p6). 2631/// 2632/// \param PrevDecl the previous declaration found by name 2633/// lookup 2634/// 2635/// \param DC the context in which the new declaration is being 2636/// declared. 2637/// 2638/// \returns true if PrevDecl is an out-of-scope previous declaration 2639/// for a new delcaration with the same name. 2640static bool 2641isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2642 ASTContext &Context) { 2643 if (!PrevDecl) 2644 return false; 2645 2646 if (!PrevDecl->hasLinkage()) 2647 return false; 2648 2649 if (Context.getLangOptions().CPlusPlus) { 2650 // C++ [basic.link]p6: 2651 // If there is a visible declaration of an entity with linkage 2652 // having the same name and type, ignoring entities declared 2653 // outside the innermost enclosing namespace scope, the block 2654 // scope declaration declares that same entity and receives the 2655 // linkage of the previous declaration. 2656 DeclContext *OuterContext = DC->getRedeclContext(); 2657 if (!OuterContext->isFunctionOrMethod()) 2658 // This rule only applies to block-scope declarations. 2659 return false; 2660 2661 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2662 if (PrevOuterContext->isRecord()) 2663 // We found a member function: ignore it. 2664 return false; 2665 2666 // Find the innermost enclosing namespace for the new and 2667 // previous declarations. 2668 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2669 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2670 2671 // The previous declaration is in a different namespace, so it 2672 // isn't the same function. 2673 if (!OuterContext->Equals(PrevOuterContext)) 2674 return false; 2675 } 2676 2677 return true; 2678} 2679 2680static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2681 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2682 if (!SS.isSet()) return; 2683 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2684 SS.getRange()); 2685} 2686 2687NamedDecl* 2688Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 2689 QualType R, TypeSourceInfo *TInfo, 2690 LookupResult &Previous, 2691 MultiTemplateParamsArg TemplateParamLists, 2692 bool &Redeclaration) { 2693 DeclarationName Name = GetNameForDeclarator(D).getName(); 2694 2695 // Check that there are no default arguments (C++ only). 2696 if (getLangOptions().CPlusPlus) 2697 CheckExtraCXXDefaultArguments(D); 2698 2699 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2700 assert(SCSpec != DeclSpec::SCS_typedef && 2701 "Parser allowed 'typedef' as storage class VarDecl."); 2702 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2703 if (SCSpec == DeclSpec::SCS_mutable) { 2704 // mutable can only appear on non-static class members, so it's always 2705 // an error here 2706 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2707 D.setInvalidType(); 2708 SC = SC_None; 2709 } 2710 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2711 VarDecl::StorageClass SCAsWritten 2712 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2713 2714 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2715 if (!II) { 2716 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2717 << Name.getAsString(); 2718 return 0; 2719 } 2720 2721 DiagnoseFunctionSpecifiers(D); 2722 2723 if (!DC->isRecord() && S->getFnParent() == 0) { 2724 // C99 6.9p2: The storage-class specifiers auto and register shall not 2725 // appear in the declaration specifiers in an external declaration. 2726 if (SC == SC_Auto || SC == SC_Register) { 2727 2728 // If this is a register variable with an asm label specified, then this 2729 // is a GNU extension. 2730 if (SC == SC_Register && D.getAsmLabel()) 2731 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2732 else 2733 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2734 D.setInvalidType(); 2735 } 2736 } 2737 if (DC->isRecord() && !CurContext->isRecord()) { 2738 // This is an out-of-line definition of a static data member. 2739 if (SC == SC_Static) { 2740 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2741 diag::err_static_out_of_line) 2742 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2743 } else if (SC == SC_None) 2744 SC = SC_Static; 2745 } 2746 if (SC == SC_Static) { 2747 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2748 if (RD->isLocalClass()) 2749 Diag(D.getIdentifierLoc(), 2750 diag::err_static_data_member_not_allowed_in_local_class) 2751 << Name << RD->getDeclName(); 2752 } 2753 } 2754 2755 // Match up the template parameter lists with the scope specifier, then 2756 // determine whether we have a template or a template specialization. 2757 bool isExplicitSpecialization = false; 2758 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2759 bool Invalid = false; 2760 if (TemplateParameterList *TemplateParams 2761 = MatchTemplateParametersToScopeSpecifier( 2762 D.getDeclSpec().getSourceRange().getBegin(), 2763 D.getCXXScopeSpec(), 2764 (TemplateParameterList**)TemplateParamLists.get(), 2765 TemplateParamLists.size(), 2766 /*never a friend*/ false, 2767 isExplicitSpecialization, 2768 Invalid)) { 2769 // All but one template parameter lists have been matching. 2770 --NumMatchedTemplateParamLists; 2771 2772 if (TemplateParams->size() > 0) { 2773 // There is no such thing as a variable template. 2774 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2775 << II 2776 << SourceRange(TemplateParams->getTemplateLoc(), 2777 TemplateParams->getRAngleLoc()); 2778 return 0; 2779 } else { 2780 // There is an extraneous 'template<>' for this variable. Complain 2781 // about it, but allow the declaration of the variable. 2782 Diag(TemplateParams->getTemplateLoc(), 2783 diag::err_template_variable_noparams) 2784 << II 2785 << SourceRange(TemplateParams->getTemplateLoc(), 2786 TemplateParams->getRAngleLoc()); 2787 2788 isExplicitSpecialization = true; 2789 } 2790 } 2791 2792 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2793 II, R, TInfo, SC, SCAsWritten); 2794 2795 if (D.isInvalidType() || Invalid) 2796 NewVD->setInvalidDecl(); 2797 2798 SetNestedNameSpecifier(NewVD, D); 2799 2800 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2801 NewVD->setTemplateParameterListsInfo(Context, 2802 NumMatchedTemplateParamLists, 2803 (TemplateParameterList**)TemplateParamLists.release()); 2804 } 2805 2806 if (D.getDeclSpec().isThreadSpecified()) { 2807 if (NewVD->hasLocalStorage()) 2808 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2809 else if (!Context.Target.isTLSSupported()) 2810 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2811 else 2812 NewVD->setThreadSpecified(true); 2813 } 2814 2815 // Set the lexical context. If the declarator has a C++ scope specifier, the 2816 // lexical context will be different from the semantic context. 2817 NewVD->setLexicalDeclContext(CurContext); 2818 2819 // Handle attributes prior to checking for duplicates in MergeVarDecl 2820 ProcessDeclAttributes(S, NewVD, D); 2821 2822 // Handle GNU asm-label extension (encoded as an attribute). 2823 if (Expr *E = (Expr*)D.getAsmLabel()) { 2824 // The parser guarantees this is a string. 2825 StringLiteral *SE = cast<StringLiteral>(E); 2826 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2827 Context, SE->getString())); 2828 } 2829 2830 // Diagnose shadowed variables before filtering for scope. 2831 if (!D.getCXXScopeSpec().isSet()) 2832 CheckShadow(S, NewVD, Previous); 2833 2834 // Don't consider existing declarations that are in a different 2835 // scope and are out-of-semantic-context declarations (if the new 2836 // declaration has linkage). 2837 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2838 2839 // Merge the decl with the existing one if appropriate. 2840 if (!Previous.empty()) { 2841 if (Previous.isSingleResult() && 2842 isa<FieldDecl>(Previous.getFoundDecl()) && 2843 D.getCXXScopeSpec().isSet()) { 2844 // The user tried to define a non-static data member 2845 // out-of-line (C++ [dcl.meaning]p1). 2846 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2847 << D.getCXXScopeSpec().getRange(); 2848 Previous.clear(); 2849 NewVD->setInvalidDecl(); 2850 } 2851 } else if (D.getCXXScopeSpec().isSet()) { 2852 // No previous declaration in the qualifying scope. 2853 Diag(D.getIdentifierLoc(), diag::err_no_member) 2854 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2855 << D.getCXXScopeSpec().getRange(); 2856 NewVD->setInvalidDecl(); 2857 } 2858 2859 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2860 2861 // This is an explicit specialization of a static data member. Check it. 2862 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2863 CheckMemberSpecialization(NewVD, Previous)) 2864 NewVD->setInvalidDecl(); 2865 2866 // attributes declared post-definition are currently ignored 2867 // FIXME: This should be handled in attribute merging, not 2868 // here. 2869 if (Previous.isSingleResult()) { 2870 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2871 if (Def && (Def = Def->getDefinition()) && 2872 Def != NewVD && D.hasAttributes()) { 2873 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2874 Diag(Def->getLocation(), diag::note_previous_definition); 2875 } 2876 } 2877 2878 // If this is a locally-scoped extern C variable, update the map of 2879 // such variables. 2880 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2881 !NewVD->isInvalidDecl()) 2882 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2883 2884 // If there's a #pragma GCC visibility in scope, and this isn't a class 2885 // member, set the visibility of this variable. 2886 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2887 AddPushedVisibilityAttribute(NewVD); 2888 2889 MarkUnusedFileScopedDecl(NewVD); 2890 2891 return NewVD; 2892} 2893 2894/// \brief Diagnose variable or built-in function shadowing. Implements 2895/// -Wshadow. 2896/// 2897/// This method is called whenever a VarDecl is added to a "useful" 2898/// scope. 2899/// 2900/// \param S the scope in which the shadowing name is being declared 2901/// \param R the lookup of the name 2902/// 2903void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2904 // Return if warning is ignored. 2905 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2906 return; 2907 2908 // Don't diagnose declarations at file scope. The scope might not 2909 // have a DeclContext if (e.g.) we're parsing a function prototype. 2910 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2911 if (NewDC && NewDC->isFileContext()) 2912 return; 2913 2914 // Only diagnose if we're shadowing an unambiguous field or variable. 2915 if (R.getResultKind() != LookupResult::Found) 2916 return; 2917 2918 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2919 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2920 return; 2921 2922 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2923 2924 // Only warn about certain kinds of shadowing for class members. 2925 if (NewDC && NewDC->isRecord()) { 2926 // In particular, don't warn about shadowing non-class members. 2927 if (!OldDC->isRecord()) 2928 return; 2929 2930 // TODO: should we warn about static data members shadowing 2931 // static data members from base classes? 2932 2933 // TODO: don't diagnose for inaccessible shadowed members. 2934 // This is hard to do perfectly because we might friend the 2935 // shadowing context, but that's just a false negative. 2936 } 2937 2938 // Determine what kind of declaration we're shadowing. 2939 unsigned Kind; 2940 if (isa<RecordDecl>(OldDC)) { 2941 if (isa<FieldDecl>(ShadowedDecl)) 2942 Kind = 3; // field 2943 else 2944 Kind = 2; // static data member 2945 } else if (OldDC->isFileContext()) 2946 Kind = 1; // global 2947 else 2948 Kind = 0; // local 2949 2950 DeclarationName Name = R.getLookupName(); 2951 2952 // Emit warning and note. 2953 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2954 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2955} 2956 2957/// \brief Check -Wshadow without the advantage of a previous lookup. 2958void Sema::CheckShadow(Scope *S, VarDecl *D) { 2959 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2960 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2961 LookupName(R, S); 2962 CheckShadow(S, D, R); 2963} 2964 2965/// \brief Perform semantic checking on a newly-created variable 2966/// declaration. 2967/// 2968/// This routine performs all of the type-checking required for a 2969/// variable declaration once it has been built. It is used both to 2970/// check variables after they have been parsed and their declarators 2971/// have been translated into a declaration, and to check variables 2972/// that have been instantiated from a template. 2973/// 2974/// Sets NewVD->isInvalidDecl() if an error was encountered. 2975void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2976 LookupResult &Previous, 2977 bool &Redeclaration) { 2978 // If the decl is already known invalid, don't check it. 2979 if (NewVD->isInvalidDecl()) 2980 return; 2981 2982 QualType T = NewVD->getType(); 2983 2984 if (T->isObjCObjectType()) { 2985 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2986 return NewVD->setInvalidDecl(); 2987 } 2988 2989 // Emit an error if an address space was applied to decl with local storage. 2990 // This includes arrays of objects with address space qualifiers, but not 2991 // automatic variables that point to other address spaces. 2992 // ISO/IEC TR 18037 S5.1.2 2993 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 2994 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2995 return NewVD->setInvalidDecl(); 2996 } 2997 2998 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2999 && !NewVD->hasAttr<BlocksAttr>()) 3000 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3001 3002 bool isVM = T->isVariablyModifiedType(); 3003 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3004 NewVD->hasAttr<BlocksAttr>()) 3005 getCurFunction()->setHasBranchProtectedScope(); 3006 3007 if ((isVM && NewVD->hasLinkage()) || 3008 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3009 bool SizeIsNegative; 3010 llvm::APSInt Oversized; 3011 QualType FixedTy = 3012 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3013 Oversized); 3014 3015 if (FixedTy.isNull() && T->isVariableArrayType()) { 3016 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3017 // FIXME: This won't give the correct result for 3018 // int a[10][n]; 3019 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3020 3021 if (NewVD->isFileVarDecl()) 3022 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3023 << SizeRange; 3024 else if (NewVD->getStorageClass() == SC_Static) 3025 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3026 << SizeRange; 3027 else 3028 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3029 << SizeRange; 3030 return NewVD->setInvalidDecl(); 3031 } 3032 3033 if (FixedTy.isNull()) { 3034 if (NewVD->isFileVarDecl()) 3035 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3036 else 3037 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3038 return NewVD->setInvalidDecl(); 3039 } 3040 3041 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3042 NewVD->setType(FixedTy); 3043 } 3044 3045 if (Previous.empty() && NewVD->isExternC()) { 3046 // Since we did not find anything by this name and we're declaring 3047 // an extern "C" variable, look for a non-visible extern "C" 3048 // declaration with the same name. 3049 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3050 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3051 if (Pos != LocallyScopedExternalDecls.end()) 3052 Previous.addDecl(Pos->second); 3053 } 3054 3055 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3056 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3057 << T; 3058 return NewVD->setInvalidDecl(); 3059 } 3060 3061 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3062 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3063 return NewVD->setInvalidDecl(); 3064 } 3065 3066 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3067 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3068 return NewVD->setInvalidDecl(); 3069 } 3070 3071 // Function pointers and references cannot have qualified function type, only 3072 // function pointer-to-members can do that. 3073 QualType Pointee; 3074 unsigned PtrOrRef = 0; 3075 if (const PointerType *Ptr = T->getAs<PointerType>()) 3076 Pointee = Ptr->getPointeeType(); 3077 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3078 Pointee = Ref->getPointeeType(); 3079 PtrOrRef = 1; 3080 } 3081 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3082 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3083 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3084 << PtrOrRef; 3085 return NewVD->setInvalidDecl(); 3086 } 3087 3088 if (!Previous.empty()) { 3089 Redeclaration = true; 3090 MergeVarDecl(NewVD, Previous); 3091 } 3092} 3093 3094/// \brief Data used with FindOverriddenMethod 3095struct FindOverriddenMethodData { 3096 Sema *S; 3097 CXXMethodDecl *Method; 3098}; 3099 3100/// \brief Member lookup function that determines whether a given C++ 3101/// method overrides a method in a base class, to be used with 3102/// CXXRecordDecl::lookupInBases(). 3103static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3104 CXXBasePath &Path, 3105 void *UserData) { 3106 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3107 3108 FindOverriddenMethodData *Data 3109 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3110 3111 DeclarationName Name = Data->Method->getDeclName(); 3112 3113 // FIXME: Do we care about other names here too? 3114 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3115 // We really want to find the base class destructor here. 3116 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3117 CanQualType CT = Data->S->Context.getCanonicalType(T); 3118 3119 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3120 } 3121 3122 for (Path.Decls = BaseRecord->lookup(Name); 3123 Path.Decls.first != Path.Decls.second; 3124 ++Path.Decls.first) { 3125 NamedDecl *D = *Path.Decls.first; 3126 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3127 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3128 return true; 3129 } 3130 } 3131 3132 return false; 3133} 3134 3135/// AddOverriddenMethods - See if a method overrides any in the base classes, 3136/// and if so, check that it's a valid override and remember it. 3137void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3138 // Look for virtual methods in base classes that this method might override. 3139 CXXBasePaths Paths; 3140 FindOverriddenMethodData Data; 3141 Data.Method = MD; 3142 Data.S = this; 3143 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3144 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3145 E = Paths.found_decls_end(); I != E; ++I) { 3146 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3147 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3148 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3149 !CheckOverridingFunctionAttributes(MD, OldMD)) 3150 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3151 } 3152 } 3153 } 3154} 3155 3156NamedDecl* 3157Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3158 QualType R, TypeSourceInfo *TInfo, 3159 LookupResult &Previous, 3160 MultiTemplateParamsArg TemplateParamLists, 3161 bool IsFunctionDefinition, bool &Redeclaration) { 3162 assert(R.getTypePtr()->isFunctionType()); 3163 3164 // TODO: consider using NameInfo for diagnostic. 3165 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3166 DeclarationName Name = NameInfo.getName(); 3167 FunctionDecl::StorageClass SC = SC_None; 3168 switch (D.getDeclSpec().getStorageClassSpec()) { 3169 default: assert(0 && "Unknown storage class!"); 3170 case DeclSpec::SCS_auto: 3171 case DeclSpec::SCS_register: 3172 case DeclSpec::SCS_mutable: 3173 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3174 diag::err_typecheck_sclass_func); 3175 D.setInvalidType(); 3176 break; 3177 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3178 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3179 case DeclSpec::SCS_static: { 3180 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3181 // C99 6.7.1p5: 3182 // The declaration of an identifier for a function that has 3183 // block scope shall have no explicit storage-class specifier 3184 // other than extern 3185 // See also (C++ [dcl.stc]p4). 3186 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3187 diag::err_static_block_func); 3188 SC = SC_None; 3189 } else 3190 SC = SC_Static; 3191 break; 3192 } 3193 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3194 } 3195 3196 if (D.getDeclSpec().isThreadSpecified()) 3197 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3198 3199 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3200 bool isInline = D.getDeclSpec().isInlineSpecified(); 3201 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3202 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3203 3204 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3205 FunctionDecl::StorageClass SCAsWritten 3206 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3207 3208 // Check that the return type is not an abstract class type. 3209 // For record types, this is done by the AbstractClassUsageDiagnoser once 3210 // the class has been completely parsed. 3211 if (!DC->isRecord() && 3212 RequireNonAbstractType(D.getIdentifierLoc(), 3213 R->getAs<FunctionType>()->getResultType(), 3214 diag::err_abstract_type_in_decl, 3215 AbstractReturnType)) 3216 D.setInvalidType(); 3217 3218 // Do not allow returning a objc interface by-value. 3219 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3220 Diag(D.getIdentifierLoc(), 3221 diag::err_object_cannot_be_passed_returned_by_value) << 0 3222 << R->getAs<FunctionType>()->getResultType(); 3223 D.setInvalidType(); 3224 } 3225 3226 bool isVirtualOkay = false; 3227 FunctionDecl *NewFD; 3228 3229 if (isFriend) { 3230 // C++ [class.friend]p5 3231 // A function can be defined in a friend declaration of a 3232 // class . . . . Such a function is implicitly inline. 3233 isInline |= IsFunctionDefinition; 3234 } 3235 3236 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3237 // This is a C++ constructor declaration. 3238 assert(DC->isRecord() && 3239 "Constructors can only be declared in a member context"); 3240 3241 R = CheckConstructorDeclarator(D, R, SC); 3242 3243 // Create the new declaration 3244 NewFD = CXXConstructorDecl::Create(Context, 3245 cast<CXXRecordDecl>(DC), 3246 NameInfo, R, TInfo, 3247 isExplicit, isInline, 3248 /*isImplicitlyDeclared=*/false); 3249 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3250 // This is a C++ destructor declaration. 3251 if (DC->isRecord()) { 3252 R = CheckDestructorDeclarator(D, R, SC); 3253 3254 NewFD = CXXDestructorDecl::Create(Context, 3255 cast<CXXRecordDecl>(DC), 3256 NameInfo, R, 3257 isInline, 3258 /*isImplicitlyDeclared=*/false); 3259 NewFD->setTypeSourceInfo(TInfo); 3260 3261 isVirtualOkay = true; 3262 } else { 3263 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3264 3265 // Create a FunctionDecl to satisfy the function definition parsing 3266 // code path. 3267 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3268 Name, R, TInfo, SC, SCAsWritten, isInline, 3269 /*hasPrototype=*/true); 3270 D.setInvalidType(); 3271 } 3272 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3273 if (!DC->isRecord()) { 3274 Diag(D.getIdentifierLoc(), 3275 diag::err_conv_function_not_member); 3276 return 0; 3277 } 3278 3279 CheckConversionDeclarator(D, R, SC); 3280 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3281 NameInfo, R, TInfo, 3282 isInline, isExplicit); 3283 3284 isVirtualOkay = true; 3285 } else if (DC->isRecord()) { 3286 // If the of the function is the same as the name of the record, then this 3287 // must be an invalid constructor that has a return type. 3288 // (The parser checks for a return type and makes the declarator a 3289 // constructor if it has no return type). 3290 // must have an invalid constructor that has a return type 3291 if (Name.getAsIdentifierInfo() && 3292 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3293 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3294 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3295 << SourceRange(D.getIdentifierLoc()); 3296 return 0; 3297 } 3298 3299 bool isStatic = SC == SC_Static; 3300 3301 // [class.free]p1: 3302 // Any allocation function for a class T is a static member 3303 // (even if not explicitly declared static). 3304 if (Name.getCXXOverloadedOperator() == OO_New || 3305 Name.getCXXOverloadedOperator() == OO_Array_New) 3306 isStatic = true; 3307 3308 // [class.free]p6 Any deallocation function for a class X is a static member 3309 // (even if not explicitly declared static). 3310 if (Name.getCXXOverloadedOperator() == OO_Delete || 3311 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3312 isStatic = true; 3313 3314 // This is a C++ method declaration. 3315 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3316 NameInfo, R, TInfo, 3317 isStatic, SCAsWritten, isInline); 3318 3319 isVirtualOkay = !isStatic; 3320 } else { 3321 // Determine whether the function was written with a 3322 // prototype. This true when: 3323 // - we're in C++ (where every function has a prototype), 3324 // - there is a prototype in the declarator, or 3325 // - the type R of the function is some kind of typedef or other reference 3326 // to a type name (which eventually refers to a function type). 3327 bool HasPrototype = 3328 getLangOptions().CPlusPlus || 3329 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3330 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3331 3332 NewFD = FunctionDecl::Create(Context, DC, 3333 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3334 HasPrototype); 3335 } 3336 3337 if (D.isInvalidType()) 3338 NewFD->setInvalidDecl(); 3339 3340 SetNestedNameSpecifier(NewFD, D); 3341 3342 // Set the lexical context. If the declarator has a C++ 3343 // scope specifier, or is the object of a friend declaration, the 3344 // lexical context will be different from the semantic context. 3345 NewFD->setLexicalDeclContext(CurContext); 3346 3347 // Match up the template parameter lists with the scope specifier, then 3348 // determine whether we have a template or a template specialization. 3349 FunctionTemplateDecl *FunctionTemplate = 0; 3350 bool isExplicitSpecialization = false; 3351 bool isFunctionTemplateSpecialization = false; 3352 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3353 bool Invalid = false; 3354 if (TemplateParameterList *TemplateParams 3355 = MatchTemplateParametersToScopeSpecifier( 3356 D.getDeclSpec().getSourceRange().getBegin(), 3357 D.getCXXScopeSpec(), 3358 (TemplateParameterList**)TemplateParamLists.get(), 3359 TemplateParamLists.size(), 3360 isFriend, 3361 isExplicitSpecialization, 3362 Invalid)) { 3363 // All but one template parameter lists have been matching. 3364 --NumMatchedTemplateParamLists; 3365 3366 if (TemplateParams->size() > 0) { 3367 // This is a function template 3368 3369 // Check that we can declare a template here. 3370 if (CheckTemplateDeclScope(S, TemplateParams)) 3371 return 0; 3372 3373 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3374 NewFD->getLocation(), 3375 Name, TemplateParams, 3376 NewFD); 3377 FunctionTemplate->setLexicalDeclContext(CurContext); 3378 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3379 } else { 3380 // This is a function template specialization. 3381 isFunctionTemplateSpecialization = true; 3382 3383 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3384 if (isFriend && isFunctionTemplateSpecialization) { 3385 // We want to remove the "template<>", found here. 3386 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3387 3388 // If we remove the template<> and the name is not a 3389 // template-id, we're actually silently creating a problem: 3390 // the friend declaration will refer to an untemplated decl, 3391 // and clearly the user wants a template specialization. So 3392 // we need to insert '<>' after the name. 3393 SourceLocation InsertLoc; 3394 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3395 InsertLoc = D.getName().getSourceRange().getEnd(); 3396 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3397 } 3398 3399 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3400 << Name << RemoveRange 3401 << FixItHint::CreateRemoval(RemoveRange) 3402 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3403 } 3404 } 3405 } 3406 3407 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3408 NewFD->setTemplateParameterListsInfo(Context, 3409 NumMatchedTemplateParamLists, 3410 (TemplateParameterList**)TemplateParamLists.release()); 3411 } 3412 3413 if (Invalid) { 3414 NewFD->setInvalidDecl(); 3415 if (FunctionTemplate) 3416 FunctionTemplate->setInvalidDecl(); 3417 } 3418 3419 // C++ [dcl.fct.spec]p5: 3420 // The virtual specifier shall only be used in declarations of 3421 // nonstatic class member functions that appear within a 3422 // member-specification of a class declaration; see 10.3. 3423 // 3424 if (isVirtual && !NewFD->isInvalidDecl()) { 3425 if (!isVirtualOkay) { 3426 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3427 diag::err_virtual_non_function); 3428 } else if (!CurContext->isRecord()) { 3429 // 'virtual' was specified outside of the class. 3430 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3431 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3432 } else { 3433 // Okay: Add virtual to the method. 3434 NewFD->setVirtualAsWritten(true); 3435 } 3436 } 3437 3438 // C++ [dcl.fct.spec]p3: 3439 // The inline specifier shall not appear on a block scope function declaration. 3440 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3441 if (CurContext->isFunctionOrMethod()) { 3442 // 'inline' is not allowed on block scope function declaration. 3443 Diag(D.getDeclSpec().getInlineSpecLoc(), 3444 diag::err_inline_declaration_block_scope) << Name 3445 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3446 } 3447 } 3448 3449 // C++ [dcl.fct.spec]p6: 3450 // The explicit specifier shall be used only in the declaration of a 3451 // constructor or conversion function within its class definition; see 12.3.1 3452 // and 12.3.2. 3453 if (isExplicit && !NewFD->isInvalidDecl()) { 3454 if (!CurContext->isRecord()) { 3455 // 'explicit' was specified outside of the class. 3456 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3457 diag::err_explicit_out_of_class) 3458 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3459 } else if (!isa<CXXConstructorDecl>(NewFD) && 3460 !isa<CXXConversionDecl>(NewFD)) { 3461 // 'explicit' was specified on a function that wasn't a constructor 3462 // or conversion function. 3463 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3464 diag::err_explicit_non_ctor_or_conv_function) 3465 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3466 } 3467 } 3468 3469 // Filter out previous declarations that don't match the scope. 3470 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3471 3472 if (isFriend) { 3473 // DC is the namespace in which the function is being declared. 3474 assert((DC->isFileContext() || !Previous.empty() || 3475 (D.getCXXScopeSpec().isSet() && 3476 D.getCXXScopeSpec().getScopeRep()->isDependent())) && 3477 "previously-undeclared friend function being created " 3478 "in a non-namespace context"); 3479 3480 // For now, claim that the objects have no previous declaration. 3481 if (FunctionTemplate) { 3482 FunctionTemplate->setObjectOfFriendDecl(false); 3483 FunctionTemplate->setAccess(AS_public); 3484 } 3485 NewFD->setObjectOfFriendDecl(false); 3486 NewFD->setAccess(AS_public); 3487 } 3488 3489 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3490 !CurContext->isRecord()) { 3491 // C++ [class.static]p1: 3492 // A data or function member of a class may be declared static 3493 // in a class definition, in which case it is a static member of 3494 // the class. 3495 3496 // Complain about the 'static' specifier if it's on an out-of-line 3497 // member function definition. 3498 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3499 diag::err_static_out_of_line) 3500 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3501 } 3502 3503 // Handle GNU asm-label extension (encoded as an attribute). 3504 if (Expr *E = (Expr*) D.getAsmLabel()) { 3505 // The parser guarantees this is a string. 3506 StringLiteral *SE = cast<StringLiteral>(E); 3507 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3508 SE->getString())); 3509 } 3510 3511 // Copy the parameter declarations from the declarator D to the function 3512 // declaration NewFD, if they are available. First scavenge them into Params. 3513 llvm::SmallVector<ParmVarDecl*, 16> Params; 3514 if (D.getNumTypeObjects() > 0) { 3515 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3516 3517 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3518 // function that takes no arguments, not a function that takes a 3519 // single void argument. 3520 // We let through "const void" here because Sema::GetTypeForDeclarator 3521 // already checks for that case. 3522 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3523 FTI.ArgInfo[0].Param && 3524 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3525 // Empty arg list, don't push any params. 3526 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3527 3528 // In C++, the empty parameter-type-list must be spelled "void"; a 3529 // typedef of void is not permitted. 3530 if (getLangOptions().CPlusPlus && 3531 Param->getType().getUnqualifiedType() != Context.VoidTy) 3532 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3533 // FIXME: Leaks decl? 3534 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3535 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3536 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3537 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3538 Param->setDeclContext(NewFD); 3539 Params.push_back(Param); 3540 3541 if (Param->isInvalidDecl()) 3542 NewFD->setInvalidDecl(); 3543 } 3544 } 3545 3546 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3547 // When we're declaring a function with a typedef, typeof, etc as in the 3548 // following example, we'll need to synthesize (unnamed) 3549 // parameters for use in the declaration. 3550 // 3551 // @code 3552 // typedef void fn(int); 3553 // fn f; 3554 // @endcode 3555 3556 // Synthesize a parameter for each argument type. 3557 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3558 AE = FT->arg_type_end(); AI != AE; ++AI) { 3559 ParmVarDecl *Param = 3560 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3561 Params.push_back(Param); 3562 } 3563 } else { 3564 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3565 "Should not need args for typedef of non-prototype fn"); 3566 } 3567 // Finally, we know we have the right number of parameters, install them. 3568 NewFD->setParams(Params.data(), Params.size()); 3569 3570 // If the declarator is a template-id, translate the parser's template 3571 // argument list into our AST format. 3572 bool HasExplicitTemplateArgs = false; 3573 TemplateArgumentListInfo TemplateArgs; 3574 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3575 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3576 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3577 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3578 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3579 TemplateId->getTemplateArgs(), 3580 TemplateId->NumArgs); 3581 translateTemplateArguments(TemplateArgsPtr, 3582 TemplateArgs); 3583 TemplateArgsPtr.release(); 3584 3585 HasExplicitTemplateArgs = true; 3586 3587 if (FunctionTemplate) { 3588 // FIXME: Diagnose function template with explicit template 3589 // arguments. 3590 HasExplicitTemplateArgs = false; 3591 } else if (!isFunctionTemplateSpecialization && 3592 !D.getDeclSpec().isFriendSpecified()) { 3593 // We have encountered something that the user meant to be a 3594 // specialization (because it has explicitly-specified template 3595 // arguments) but that was not introduced with a "template<>" (or had 3596 // too few of them). 3597 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3598 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3599 << FixItHint::CreateInsertion( 3600 D.getDeclSpec().getSourceRange().getBegin(), 3601 "template<> "); 3602 isFunctionTemplateSpecialization = true; 3603 } else { 3604 // "friend void foo<>(int);" is an implicit specialization decl. 3605 isFunctionTemplateSpecialization = true; 3606 } 3607 } else if (isFriend && isFunctionTemplateSpecialization) { 3608 // This combination is only possible in a recovery case; the user 3609 // wrote something like: 3610 // template <> friend void foo(int); 3611 // which we're recovering from as if the user had written: 3612 // friend void foo<>(int); 3613 // Go ahead and fake up a template id. 3614 HasExplicitTemplateArgs = true; 3615 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3616 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3617 } 3618 3619 // If it's a friend (and only if it's a friend), it's possible 3620 // that either the specialized function type or the specialized 3621 // template is dependent, and therefore matching will fail. In 3622 // this case, don't check the specialization yet. 3623 if (isFunctionTemplateSpecialization && isFriend && 3624 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3625 assert(HasExplicitTemplateArgs && 3626 "friend function specialization without template args"); 3627 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3628 Previous)) 3629 NewFD->setInvalidDecl(); 3630 } else if (isFunctionTemplateSpecialization) { 3631 if (CheckFunctionTemplateSpecialization(NewFD, 3632 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3633 Previous)) 3634 NewFD->setInvalidDecl(); 3635 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3636 if (CheckMemberSpecialization(NewFD, Previous)) 3637 NewFD->setInvalidDecl(); 3638 } 3639 3640 // Perform semantic checking on the function declaration. 3641 bool OverloadableAttrRequired = false; // FIXME: HACK! 3642 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3643 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3644 3645 assert((NewFD->isInvalidDecl() || !Redeclaration || 3646 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3647 "previous declaration set still overloaded"); 3648 3649 NamedDecl *PrincipalDecl = (FunctionTemplate 3650 ? cast<NamedDecl>(FunctionTemplate) 3651 : NewFD); 3652 3653 if (isFriend && Redeclaration) { 3654 AccessSpecifier Access = AS_public; 3655 if (!NewFD->isInvalidDecl()) 3656 Access = NewFD->getPreviousDeclaration()->getAccess(); 3657 3658 NewFD->setAccess(Access); 3659 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3660 3661 PrincipalDecl->setObjectOfFriendDecl(true); 3662 } 3663 3664 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3665 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3666 PrincipalDecl->setNonMemberOperator(); 3667 3668 // If we have a function template, check the template parameter 3669 // list. This will check and merge default template arguments. 3670 if (FunctionTemplate) { 3671 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3672 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3673 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3674 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3675 : TPC_FunctionTemplate); 3676 } 3677 3678 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3679 if (isFriend || !CurContext->isRecord()) { 3680 // Fake up an access specifier if it's supposed to be a class member. 3681 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3682 NewFD->setAccess(AS_public); 3683 3684 // An out-of-line member function declaration must also be a 3685 // definition (C++ [dcl.meaning]p1). 3686 // Note that this is not the case for explicit specializations of 3687 // function templates or member functions of class templates, per 3688 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3689 // for compatibility with old SWIG code which likes to generate them. 3690 if (!IsFunctionDefinition && !isFriend && 3691 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3692 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3693 << D.getCXXScopeSpec().getRange(); 3694 } 3695 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3696 // The user tried to provide an out-of-line definition for a 3697 // function that is a member of a class or namespace, but there 3698 // was no such member function declared (C++ [class.mfct]p2, 3699 // C++ [namespace.memdef]p2). For example: 3700 // 3701 // class X { 3702 // void f() const; 3703 // }; 3704 // 3705 // void X::f() { } // ill-formed 3706 // 3707 // Complain about this problem, and attempt to suggest close 3708 // matches (e.g., those that differ only in cv-qualifiers and 3709 // whether the parameter types are references). 3710 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3711 << Name << DC << D.getCXXScopeSpec().getRange(); 3712 NewFD->setInvalidDecl(); 3713 3714 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3715 ForRedeclaration); 3716 LookupQualifiedName(Prev, DC); 3717 assert(!Prev.isAmbiguous() && 3718 "Cannot have an ambiguity in previous-declaration lookup"); 3719 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3720 Func != FuncEnd; ++Func) { 3721 if (isa<FunctionDecl>(*Func) && 3722 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3723 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3724 } 3725 } 3726 } else { 3727 // The user provided a superfluous scope specifier inside a class definition: 3728 // 3729 // class X { 3730 // void X::f(); 3731 // }; 3732 Diag(NewFD->getLocation(), diag::warn_member_extra_qualification) 3733 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 3734 } 3735 } 3736 3737 // Handle attributes. We need to have merged decls when handling attributes 3738 // (for example to check for conflicts, etc). 3739 // FIXME: This needs to happen before we merge declarations. Then, 3740 // let attribute merging cope with attribute conflicts. 3741 ProcessDeclAttributes(S, NewFD, D); 3742 3743 // attributes declared post-definition are currently ignored 3744 // FIXME: This should happen during attribute merging 3745 if (Redeclaration && Previous.isSingleResult()) { 3746 const FunctionDecl *Def; 3747 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3748 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3749 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3750 Diag(Def->getLocation(), diag::note_previous_definition); 3751 } 3752 } 3753 3754 AddKnownFunctionAttributes(NewFD); 3755 3756 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3757 // If a function name is overloadable in C, then every function 3758 // with that name must be marked "overloadable". 3759 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3760 << Redeclaration << NewFD; 3761 if (!Previous.empty()) 3762 Diag(Previous.getRepresentativeDecl()->getLocation(), 3763 diag::note_attribute_overloadable_prev_overload); 3764 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3765 } 3766 3767 if (NewFD->hasAttr<OverloadableAttr>() && 3768 !NewFD->getType()->getAs<FunctionProtoType>()) { 3769 Diag(NewFD->getLocation(), 3770 diag::err_attribute_overloadable_no_prototype) 3771 << NewFD; 3772 3773 // Turn this into a variadic function with no parameters. 3774 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3775 QualType R = Context.getFunctionType(FT->getResultType(), 3776 0, 0, true, 0, false, false, 0, 0, 3777 FT->getExtInfo()); 3778 NewFD->setType(R); 3779 } 3780 3781 // If there's a #pragma GCC visibility in scope, and this isn't a class 3782 // member, set the visibility of this function. 3783 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3784 AddPushedVisibilityAttribute(NewFD); 3785 3786 // If this is a locally-scoped extern C function, update the 3787 // map of such names. 3788 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3789 && !NewFD->isInvalidDecl()) 3790 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3791 3792 // Set this FunctionDecl's range up to the right paren. 3793 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3794 3795 if (FunctionTemplate && NewFD->isInvalidDecl()) 3796 FunctionTemplate->setInvalidDecl(); 3797 3798 if (FunctionTemplate) 3799 return FunctionTemplate; 3800 3801 MarkUnusedFileScopedDecl(NewFD); 3802 3803 return NewFD; 3804} 3805 3806/// \brief Perform semantic checking of a new function declaration. 3807/// 3808/// Performs semantic analysis of the new function declaration 3809/// NewFD. This routine performs all semantic checking that does not 3810/// require the actual declarator involved in the declaration, and is 3811/// used both for the declaration of functions as they are parsed 3812/// (called via ActOnDeclarator) and for the declaration of functions 3813/// that have been instantiated via C++ template instantiation (called 3814/// via InstantiateDecl). 3815/// 3816/// \param IsExplicitSpecialiation whether this new function declaration is 3817/// an explicit specialization of the previous declaration. 3818/// 3819/// This sets NewFD->isInvalidDecl() to true if there was an error. 3820void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3821 LookupResult &Previous, 3822 bool IsExplicitSpecialization, 3823 bool &Redeclaration, 3824 bool &OverloadableAttrRequired) { 3825 // If NewFD is already known erroneous, don't do any of this checking. 3826 if (NewFD->isInvalidDecl()) { 3827 // If this is a class member, mark the class invalid immediately. 3828 // This avoids some consistency errors later. 3829 if (isa<CXXMethodDecl>(NewFD)) 3830 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3831 3832 return; 3833 } 3834 3835 if (NewFD->getResultType()->isVariablyModifiedType()) { 3836 // Functions returning a variably modified type violate C99 6.7.5.2p2 3837 // because all functions have linkage. 3838 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3839 return NewFD->setInvalidDecl(); 3840 } 3841 3842 if (NewFD->isMain()) 3843 CheckMain(NewFD); 3844 3845 // Check for a previous declaration of this name. 3846 if (Previous.empty() && NewFD->isExternC()) { 3847 // Since we did not find anything by this name and we're declaring 3848 // an extern "C" function, look for a non-visible extern "C" 3849 // declaration with the same name. 3850 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3851 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3852 if (Pos != LocallyScopedExternalDecls.end()) 3853 Previous.addDecl(Pos->second); 3854 } 3855 3856 // Merge or overload the declaration with an existing declaration of 3857 // the same name, if appropriate. 3858 if (!Previous.empty()) { 3859 // Determine whether NewFD is an overload of PrevDecl or 3860 // a declaration that requires merging. If it's an overload, 3861 // there's no more work to do here; we'll just add the new 3862 // function to the scope. 3863 3864 NamedDecl *OldDecl = 0; 3865 if (!AllowOverloadingOfFunction(Previous, Context)) { 3866 Redeclaration = true; 3867 OldDecl = Previous.getFoundDecl(); 3868 } else { 3869 if (!getLangOptions().CPlusPlus) 3870 OverloadableAttrRequired = true; 3871 3872 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3873 /*NewIsUsingDecl*/ false)) { 3874 case Ovl_Match: 3875 Redeclaration = true; 3876 break; 3877 3878 case Ovl_NonFunction: 3879 Redeclaration = true; 3880 break; 3881 3882 case Ovl_Overload: 3883 Redeclaration = false; 3884 break; 3885 } 3886 } 3887 3888 if (Redeclaration) { 3889 // NewFD and OldDecl represent declarations that need to be 3890 // merged. 3891 if (MergeFunctionDecl(NewFD, OldDecl)) 3892 return NewFD->setInvalidDecl(); 3893 3894 Previous.clear(); 3895 Previous.addDecl(OldDecl); 3896 3897 if (FunctionTemplateDecl *OldTemplateDecl 3898 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3899 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3900 FunctionTemplateDecl *NewTemplateDecl 3901 = NewFD->getDescribedFunctionTemplate(); 3902 assert(NewTemplateDecl && "Template/non-template mismatch"); 3903 if (CXXMethodDecl *Method 3904 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3905 Method->setAccess(OldTemplateDecl->getAccess()); 3906 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3907 } 3908 3909 // If this is an explicit specialization of a member that is a function 3910 // template, mark it as a member specialization. 3911 if (IsExplicitSpecialization && 3912 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3913 NewTemplateDecl->setMemberSpecialization(); 3914 assert(OldTemplateDecl->isMemberSpecialization()); 3915 } 3916 } else { 3917 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3918 NewFD->setAccess(OldDecl->getAccess()); 3919 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3920 } 3921 } 3922 } 3923 3924 // Semantic checking for this function declaration (in isolation). 3925 if (getLangOptions().CPlusPlus) { 3926 // C++-specific checks. 3927 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3928 CheckConstructor(Constructor); 3929 } else if (CXXDestructorDecl *Destructor = 3930 dyn_cast<CXXDestructorDecl>(NewFD)) { 3931 CXXRecordDecl *Record = Destructor->getParent(); 3932 QualType ClassType = Context.getTypeDeclType(Record); 3933 3934 // FIXME: Shouldn't we be able to perform this check even when the class 3935 // type is dependent? Both gcc and edg can handle that. 3936 if (!ClassType->isDependentType()) { 3937 DeclarationName Name 3938 = Context.DeclarationNames.getCXXDestructorName( 3939 Context.getCanonicalType(ClassType)); 3940// NewFD->getDeclName().dump(); 3941// Name.dump(); 3942 if (NewFD->getDeclName() != Name) { 3943 Diag(NewFD->getLocation(), diag::err_destructor_name); 3944 return NewFD->setInvalidDecl(); 3945 } 3946 } 3947 } else if (CXXConversionDecl *Conversion 3948 = dyn_cast<CXXConversionDecl>(NewFD)) { 3949 ActOnConversionDeclarator(Conversion); 3950 } 3951 3952 // Find any virtual functions that this function overrides. 3953 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3954 if (!Method->isFunctionTemplateSpecialization() && 3955 !Method->getDescribedFunctionTemplate()) 3956 AddOverriddenMethods(Method->getParent(), Method); 3957 } 3958 3959 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3960 if (NewFD->isOverloadedOperator() && 3961 CheckOverloadedOperatorDeclaration(NewFD)) 3962 return NewFD->setInvalidDecl(); 3963 3964 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3965 if (NewFD->getLiteralIdentifier() && 3966 CheckLiteralOperatorDeclaration(NewFD)) 3967 return NewFD->setInvalidDecl(); 3968 3969 // In C++, check default arguments now that we have merged decls. Unless 3970 // the lexical context is the class, because in this case this is done 3971 // during delayed parsing anyway. 3972 if (!CurContext->isRecord()) 3973 CheckCXXDefaultArguments(NewFD); 3974 } 3975} 3976 3977void Sema::CheckMain(FunctionDecl* FD) { 3978 // C++ [basic.start.main]p3: A program that declares main to be inline 3979 // or static is ill-formed. 3980 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3981 // shall not appear in a declaration of main. 3982 // static main is not an error under C99, but we should warn about it. 3983 bool isInline = FD->isInlineSpecified(); 3984 bool isStatic = FD->getStorageClass() == SC_Static; 3985 if (isInline || isStatic) { 3986 unsigned diagID = diag::warn_unusual_main_decl; 3987 if (isInline || getLangOptions().CPlusPlus) 3988 diagID = diag::err_unusual_main_decl; 3989 3990 int which = isStatic + (isInline << 1) - 1; 3991 Diag(FD->getLocation(), diagID) << which; 3992 } 3993 3994 QualType T = FD->getType(); 3995 assert(T->isFunctionType() && "function decl is not of function type"); 3996 const FunctionType* FT = T->getAs<FunctionType>(); 3997 3998 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3999 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 4000 TypeLoc TL = TSI->getTypeLoc(); 4001 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 4002 diag::err_main_returns_nonint); 4003 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 4004 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4005 "int"); 4006 } 4007 FD->setInvalidDecl(true); 4008 } 4009 4010 // Treat protoless main() as nullary. 4011 if (isa<FunctionNoProtoType>(FT)) return; 4012 4013 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4014 unsigned nparams = FTP->getNumArgs(); 4015 assert(FD->getNumParams() == nparams); 4016 4017 bool HasExtraParameters = (nparams > 3); 4018 4019 // Darwin passes an undocumented fourth argument of type char**. If 4020 // other platforms start sprouting these, the logic below will start 4021 // getting shifty. 4022 if (nparams == 4 && 4023 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4024 HasExtraParameters = false; 4025 4026 if (HasExtraParameters) { 4027 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4028 FD->setInvalidDecl(true); 4029 nparams = 3; 4030 } 4031 4032 // FIXME: a lot of the following diagnostics would be improved 4033 // if we had some location information about types. 4034 4035 QualType CharPP = 4036 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4037 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4038 4039 for (unsigned i = 0; i < nparams; ++i) { 4040 QualType AT = FTP->getArgType(i); 4041 4042 bool mismatch = true; 4043 4044 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4045 mismatch = false; 4046 else if (Expected[i] == CharPP) { 4047 // As an extension, the following forms are okay: 4048 // char const ** 4049 // char const * const * 4050 // char * const * 4051 4052 QualifierCollector qs; 4053 const PointerType* PT; 4054 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4055 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4056 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4057 qs.removeConst(); 4058 mismatch = !qs.empty(); 4059 } 4060 } 4061 4062 if (mismatch) { 4063 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4064 // TODO: suggest replacing given type with expected type 4065 FD->setInvalidDecl(true); 4066 } 4067 } 4068 4069 if (nparams == 1 && !FD->isInvalidDecl()) { 4070 Diag(FD->getLocation(), diag::warn_main_one_arg); 4071 } 4072} 4073 4074bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4075 // FIXME: Need strict checking. In C89, we need to check for 4076 // any assignment, increment, decrement, function-calls, or 4077 // commas outside of a sizeof. In C99, it's the same list, 4078 // except that the aforementioned are allowed in unevaluated 4079 // expressions. Everything else falls under the 4080 // "may accept other forms of constant expressions" exception. 4081 // (We never end up here for C++, so the constant expression 4082 // rules there don't matter.) 4083 if (Init->isConstantInitializer(Context, false)) 4084 return false; 4085 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4086 << Init->getSourceRange(); 4087 return true; 4088} 4089 4090void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4091 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4092} 4093 4094/// AddInitializerToDecl - Adds the initializer Init to the 4095/// declaration dcl. If DirectInit is true, this is C++ direct 4096/// initialization rather than copy initialization. 4097void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4098 // If there is no declaration, there was an error parsing it. Just ignore 4099 // the initializer. 4100 if (RealDecl == 0) 4101 return; 4102 4103 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4104 // With declarators parsed the way they are, the parser cannot 4105 // distinguish between a normal initializer and a pure-specifier. 4106 // Thus this grotesque test. 4107 IntegerLiteral *IL; 4108 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4109 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4110 CheckPureMethod(Method, Init->getSourceRange()); 4111 else { 4112 Diag(Method->getLocation(), diag::err_member_function_initialization) 4113 << Method->getDeclName() << Init->getSourceRange(); 4114 Method->setInvalidDecl(); 4115 } 4116 return; 4117 } 4118 4119 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4120 if (!VDecl) { 4121 if (getLangOptions().CPlusPlus && 4122 RealDecl->getLexicalDeclContext()->isRecord() && 4123 isa<NamedDecl>(RealDecl)) 4124 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4125 else 4126 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4127 RealDecl->setInvalidDecl(); 4128 return; 4129 } 4130 4131 4132 4133 // A definition must end up with a complete type, which means it must be 4134 // complete with the restriction that an array type might be completed by the 4135 // initializer; note that later code assumes this restriction. 4136 QualType BaseDeclType = VDecl->getType(); 4137 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4138 BaseDeclType = Array->getElementType(); 4139 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4140 diag::err_typecheck_decl_incomplete_type)) { 4141 RealDecl->setInvalidDecl(); 4142 return; 4143 } 4144 4145 // The variable can not have an abstract class type. 4146 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4147 diag::err_abstract_type_in_decl, 4148 AbstractVariableType)) 4149 VDecl->setInvalidDecl(); 4150 4151 const VarDecl *Def; 4152 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4153 Diag(VDecl->getLocation(), diag::err_redefinition) 4154 << VDecl->getDeclName(); 4155 Diag(Def->getLocation(), diag::note_previous_definition); 4156 VDecl->setInvalidDecl(); 4157 return; 4158 } 4159 4160 // C++ [class.static.data]p4 4161 // If a static data member is of const integral or const 4162 // enumeration type, its declaration in the class definition can 4163 // specify a constant-initializer which shall be an integral 4164 // constant expression (5.19). In that case, the member can appear 4165 // in integral constant expressions. The member shall still be 4166 // defined in a namespace scope if it is used in the program and the 4167 // namespace scope definition shall not contain an initializer. 4168 // 4169 // We already performed a redefinition check above, but for static 4170 // data members we also need to check whether there was an in-class 4171 // declaration with an initializer. 4172 const VarDecl* PrevInit = 0; 4173 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4174 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4175 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4176 return; 4177 } 4178 4179 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4180 getCurFunction()->setHasBranchProtectedScope(); 4181 4182 // Capture the variable that is being initialized and the style of 4183 // initialization. 4184 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4185 4186 // FIXME: Poor source location information. 4187 InitializationKind Kind 4188 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4189 Init->getLocStart(), 4190 Init->getLocEnd()) 4191 : InitializationKind::CreateCopy(VDecl->getLocation(), 4192 Init->getLocStart()); 4193 4194 // Get the decls type and save a reference for later, since 4195 // CheckInitializerTypes may change it. 4196 QualType DclT = VDecl->getType(), SavT = DclT; 4197 if (VDecl->isBlockVarDecl()) { 4198 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4199 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4200 VDecl->setInvalidDecl(); 4201 } else if (!VDecl->isInvalidDecl()) { 4202 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4203 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4204 MultiExprArg(*this, &Init, 1), 4205 &DclT); 4206 if (Result.isInvalid()) { 4207 VDecl->setInvalidDecl(); 4208 return; 4209 } 4210 4211 Init = Result.takeAs<Expr>(); 4212 4213 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4214 // Don't check invalid declarations to avoid emitting useless diagnostics. 4215 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4216 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4217 CheckForConstantInitializer(Init, DclT); 4218 } 4219 } 4220 } else if (VDecl->isStaticDataMember() && 4221 VDecl->getLexicalDeclContext()->isRecord()) { 4222 // This is an in-class initialization for a static data member, e.g., 4223 // 4224 // struct S { 4225 // static const int value = 17; 4226 // }; 4227 4228 // Try to perform the initialization regardless. 4229 if (!VDecl->isInvalidDecl()) { 4230 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4231 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4232 MultiExprArg(*this, &Init, 1), 4233 &DclT); 4234 if (Result.isInvalid()) { 4235 VDecl->setInvalidDecl(); 4236 return; 4237 } 4238 4239 Init = Result.takeAs<Expr>(); 4240 } 4241 4242 // C++ [class.mem]p4: 4243 // A member-declarator can contain a constant-initializer only 4244 // if it declares a static member (9.4) of const integral or 4245 // const enumeration type, see 9.4.2. 4246 QualType T = VDecl->getType(); 4247 4248 // Do nothing on dependent types. 4249 if (T->isDependentType()) { 4250 4251 // Require constness. 4252 } else if (!T.isConstQualified()) { 4253 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4254 << Init->getSourceRange(); 4255 VDecl->setInvalidDecl(); 4256 4257 // We allow integer constant expressions in all cases. 4258 } else if (T->isIntegralOrEnumerationType()) { 4259 if (!Init->isValueDependent()) { 4260 // Check whether the expression is a constant expression. 4261 llvm::APSInt Value; 4262 SourceLocation Loc; 4263 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4264 Diag(Loc, diag::err_in_class_initializer_non_constant) 4265 << Init->getSourceRange(); 4266 VDecl->setInvalidDecl(); 4267 } 4268 } 4269 4270 // We allow floating-point constants as an extension in C++03, and 4271 // C++0x has far more complicated rules that we don't really 4272 // implement fully. 4273 } else { 4274 bool Allowed = false; 4275 if (getLangOptions().CPlusPlus0x) { 4276 Allowed = T->isLiteralType(); 4277 } else if (T->isFloatingType()) { // also permits complex, which is ok 4278 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4279 << T << Init->getSourceRange(); 4280 Allowed = true; 4281 } 4282 4283 if (!Allowed) { 4284 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4285 << T << Init->getSourceRange(); 4286 VDecl->setInvalidDecl(); 4287 4288 // TODO: there are probably expressions that pass here that shouldn't. 4289 } else if (!Init->isValueDependent() && 4290 !Init->isConstantInitializer(Context, false)) { 4291 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4292 << Init->getSourceRange(); 4293 VDecl->setInvalidDecl(); 4294 } 4295 } 4296 } else if (VDecl->isFileVarDecl()) { 4297 if (VDecl->getStorageClass() == SC_Extern && 4298 (!getLangOptions().CPlusPlus || 4299 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4300 Diag(VDecl->getLocation(), diag::warn_extern_init); 4301 if (!VDecl->isInvalidDecl()) { 4302 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4303 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4304 MultiExprArg(*this, &Init, 1), 4305 &DclT); 4306 if (Result.isInvalid()) { 4307 VDecl->setInvalidDecl(); 4308 return; 4309 } 4310 4311 Init = Result.takeAs<Expr>(); 4312 } 4313 4314 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4315 // Don't check invalid declarations to avoid emitting useless diagnostics. 4316 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4317 // C99 6.7.8p4. All file scoped initializers need to be constant. 4318 CheckForConstantInitializer(Init, DclT); 4319 } 4320 } 4321 // If the type changed, it means we had an incomplete type that was 4322 // completed by the initializer. For example: 4323 // int ary[] = { 1, 3, 5 }; 4324 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4325 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4326 VDecl->setType(DclT); 4327 Init->setType(DclT); 4328 } 4329 4330 4331 // If this variable is a local declaration with record type, make sure it 4332 // doesn't have a flexible member initialization. We only support this as a 4333 // global/static definition. 4334 if (VDecl->hasLocalStorage()) 4335 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4336 if (RT->getDecl()->hasFlexibleArrayMember() && isa<InitListExpr>(Init)) { 4337 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4338 VDecl->setInvalidDecl(); 4339 } 4340 4341 // Check any implicit conversions within the expression. 4342 CheckImplicitConversions(Init, VDecl->getLocation()); 4343 4344 Init = MaybeCreateCXXExprWithTemporaries(Init); 4345 // Attach the initializer to the decl. 4346 VDecl->setInit(Init); 4347 4348 if (getLangOptions().CPlusPlus) { 4349 if (!VDecl->isInvalidDecl() && 4350 !VDecl->getDeclContext()->isDependentContext() && 4351 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4352 !Init->isConstantInitializer(Context, 4353 VDecl->getType()->isReferenceType())) 4354 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4355 << Init->getSourceRange(); 4356 4357 // Make sure we mark the destructor as used if necessary. 4358 QualType InitType = VDecl->getType(); 4359 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4360 InitType = Context.getBaseElementType(Array); 4361 if (const RecordType *Record = InitType->getAs<RecordType>()) 4362 FinalizeVarWithDestructor(VDecl, Record); 4363 } 4364 4365 return; 4366} 4367 4368/// ActOnInitializerError - Given that there was an error parsing an 4369/// initializer for the given declaration, try to return to some form 4370/// of sanity. 4371void Sema::ActOnInitializerError(Decl *D) { 4372 // Our main concern here is re-establishing invariants like "a 4373 // variable's type is either dependent or complete". 4374 if (!D || D->isInvalidDecl()) return; 4375 4376 VarDecl *VD = dyn_cast<VarDecl>(D); 4377 if (!VD) return; 4378 4379 QualType Ty = VD->getType(); 4380 if (Ty->isDependentType()) return; 4381 4382 // Require a complete type. 4383 if (RequireCompleteType(VD->getLocation(), 4384 Context.getBaseElementType(Ty), 4385 diag::err_typecheck_decl_incomplete_type)) { 4386 VD->setInvalidDecl(); 4387 return; 4388 } 4389 4390 // Require an abstract type. 4391 if (RequireNonAbstractType(VD->getLocation(), Ty, 4392 diag::err_abstract_type_in_decl, 4393 AbstractVariableType)) { 4394 VD->setInvalidDecl(); 4395 return; 4396 } 4397 4398 // Don't bother complaining about constructors or destructors, 4399 // though. 4400} 4401 4402void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4403 bool TypeContainsUndeducedAuto) { 4404 // If there is no declaration, there was an error parsing it. Just ignore it. 4405 if (RealDecl == 0) 4406 return; 4407 4408 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4409 QualType Type = Var->getType(); 4410 4411 // C++0x [dcl.spec.auto]p3 4412 if (TypeContainsUndeducedAuto) { 4413 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4414 << Var->getDeclName() << Type; 4415 Var->setInvalidDecl(); 4416 return; 4417 } 4418 4419 switch (Var->isThisDeclarationADefinition()) { 4420 case VarDecl::Definition: 4421 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4422 break; 4423 4424 // We have an out-of-line definition of a static data member 4425 // that has an in-class initializer, so we type-check this like 4426 // a declaration. 4427 // 4428 // Fall through 4429 4430 case VarDecl::DeclarationOnly: 4431 // It's only a declaration. 4432 4433 // Block scope. C99 6.7p7: If an identifier for an object is 4434 // declared with no linkage (C99 6.2.2p6), the type for the 4435 // object shall be complete. 4436 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4437 !Var->getLinkage() && !Var->isInvalidDecl() && 4438 RequireCompleteType(Var->getLocation(), Type, 4439 diag::err_typecheck_decl_incomplete_type)) 4440 Var->setInvalidDecl(); 4441 4442 // Make sure that the type is not abstract. 4443 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4444 RequireNonAbstractType(Var->getLocation(), Type, 4445 diag::err_abstract_type_in_decl, 4446 AbstractVariableType)) 4447 Var->setInvalidDecl(); 4448 return; 4449 4450 case VarDecl::TentativeDefinition: 4451 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4452 // object that has file scope without an initializer, and without a 4453 // storage-class specifier or with the storage-class specifier "static", 4454 // constitutes a tentative definition. Note: A tentative definition with 4455 // external linkage is valid (C99 6.2.2p5). 4456 if (!Var->isInvalidDecl()) { 4457 if (const IncompleteArrayType *ArrayT 4458 = Context.getAsIncompleteArrayType(Type)) { 4459 if (RequireCompleteType(Var->getLocation(), 4460 ArrayT->getElementType(), 4461 diag::err_illegal_decl_array_incomplete_type)) 4462 Var->setInvalidDecl(); 4463 } else if (Var->getStorageClass() == SC_Static) { 4464 // C99 6.9.2p3: If the declaration of an identifier for an object is 4465 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4466 // declared type shall not be an incomplete type. 4467 // NOTE: code such as the following 4468 // static struct s; 4469 // struct s { int a; }; 4470 // is accepted by gcc. Hence here we issue a warning instead of 4471 // an error and we do not invalidate the static declaration. 4472 // NOTE: to avoid multiple warnings, only check the first declaration. 4473 if (Var->getPreviousDeclaration() == 0) 4474 RequireCompleteType(Var->getLocation(), Type, 4475 diag::ext_typecheck_decl_incomplete_type); 4476 } 4477 } 4478 4479 // Record the tentative definition; we're done. 4480 if (!Var->isInvalidDecl()) 4481 TentativeDefinitions.push_back(Var); 4482 return; 4483 } 4484 4485 // Provide a specific diagnostic for uninitialized variable 4486 // definitions with incomplete array type. 4487 if (Type->isIncompleteArrayType()) { 4488 Diag(Var->getLocation(), 4489 diag::err_typecheck_incomplete_array_needs_initializer); 4490 Var->setInvalidDecl(); 4491 return; 4492 } 4493 4494 // Provide a specific diagnostic for uninitialized variable 4495 // definitions with reference type. 4496 if (Type->isReferenceType()) { 4497 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4498 << Var->getDeclName() 4499 << SourceRange(Var->getLocation(), Var->getLocation()); 4500 Var->setInvalidDecl(); 4501 return; 4502 } 4503 4504 // Do not attempt to type-check the default initializer for a 4505 // variable with dependent type. 4506 if (Type->isDependentType()) 4507 return; 4508 4509 if (Var->isInvalidDecl()) 4510 return; 4511 4512 if (RequireCompleteType(Var->getLocation(), 4513 Context.getBaseElementType(Type), 4514 diag::err_typecheck_decl_incomplete_type)) { 4515 Var->setInvalidDecl(); 4516 return; 4517 } 4518 4519 // The variable can not have an abstract class type. 4520 if (RequireNonAbstractType(Var->getLocation(), Type, 4521 diag::err_abstract_type_in_decl, 4522 AbstractVariableType)) { 4523 Var->setInvalidDecl(); 4524 return; 4525 } 4526 4527 const RecordType *Record 4528 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4529 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4530 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4531 // C++03 [dcl.init]p9: 4532 // If no initializer is specified for an object, and the 4533 // object is of (possibly cv-qualified) non-POD class type (or 4534 // array thereof), the object shall be default-initialized; if 4535 // the object is of const-qualified type, the underlying class 4536 // type shall have a user-declared default 4537 // constructor. Otherwise, if no initializer is specified for 4538 // a non- static object, the object and its subobjects, if 4539 // any, have an indeterminate initial value); if the object 4540 // or any of its subobjects are of const-qualified type, the 4541 // program is ill-formed. 4542 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4543 } else { 4544 // Check for jumps past the implicit initializer. C++0x 4545 // clarifies that this applies to a "variable with automatic 4546 // storage duration", not a "local variable". 4547 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4548 getCurFunction()->setHasBranchProtectedScope(); 4549 4550 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4551 InitializationKind Kind 4552 = InitializationKind::CreateDefault(Var->getLocation()); 4553 4554 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4555 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4556 MultiExprArg(*this, 0, 0)); 4557 if (Init.isInvalid()) 4558 Var->setInvalidDecl(); 4559 else if (Init.get()) { 4560 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4561 4562 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4563 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4564 !Var->getDeclContext()->isDependentContext() && 4565 !Var->getInit()->isConstantInitializer(Context, false)) 4566 Diag(Var->getLocation(), diag::warn_global_constructor); 4567 } 4568 } 4569 4570 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4571 FinalizeVarWithDestructor(Var, Record); 4572 } 4573} 4574 4575Sema::DeclGroupPtrTy 4576Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4577 Decl **Group, unsigned NumDecls) { 4578 llvm::SmallVector<Decl*, 8> Decls; 4579 4580 if (DS.isTypeSpecOwned()) 4581 Decls.push_back(DS.getRepAsDecl()); 4582 4583 for (unsigned i = 0; i != NumDecls; ++i) 4584 if (Decl *D = Group[i]) 4585 Decls.push_back(D); 4586 4587 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4588 Decls.data(), Decls.size())); 4589} 4590 4591 4592/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4593/// to introduce parameters into function prototype scope. 4594Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4595 const DeclSpec &DS = D.getDeclSpec(); 4596 4597 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4598 VarDecl::StorageClass StorageClass = SC_None; 4599 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4600 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4601 StorageClass = SC_Register; 4602 StorageClassAsWritten = SC_Register; 4603 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4604 Diag(DS.getStorageClassSpecLoc(), 4605 diag::err_invalid_storage_class_in_func_decl); 4606 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4607 } 4608 4609 if (D.getDeclSpec().isThreadSpecified()) 4610 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4611 4612 DiagnoseFunctionSpecifiers(D); 4613 4614 // Check that there are no default arguments inside the type of this 4615 // parameter (C++ only). 4616 if (getLangOptions().CPlusPlus) 4617 CheckExtraCXXDefaultArguments(D); 4618 4619 TagDecl *OwnedDecl = 0; 4620 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4621 QualType parmDeclType = TInfo->getType(); 4622 4623 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4624 // C++ [dcl.fct]p6: 4625 // Types shall not be defined in return or parameter types. 4626 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4627 << Context.getTypeDeclType(OwnedDecl); 4628 } 4629 4630 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4631 IdentifierInfo *II = D.getIdentifier(); 4632 if (II) { 4633 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4634 ForRedeclaration); 4635 LookupName(R, S); 4636 if (R.isSingleResult()) { 4637 NamedDecl *PrevDecl = R.getFoundDecl(); 4638 if (PrevDecl->isTemplateParameter()) { 4639 // Maybe we will complain about the shadowed template parameter. 4640 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4641 // Just pretend that we didn't see the previous declaration. 4642 PrevDecl = 0; 4643 } else if (S->isDeclScope(PrevDecl)) { 4644 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4645 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4646 4647 // Recover by removing the name 4648 II = 0; 4649 D.SetIdentifier(0, D.getIdentifierLoc()); 4650 D.setInvalidType(true); 4651 } 4652 } 4653 } 4654 4655 // Temporarily put parameter variables in the translation unit, not 4656 // the enclosing context. This prevents them from accidentally 4657 // looking like class members in C++. 4658 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4659 TInfo, parmDeclType, II, 4660 D.getIdentifierLoc(), 4661 StorageClass, StorageClassAsWritten); 4662 4663 if (D.isInvalidType()) 4664 New->setInvalidDecl(); 4665 4666 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4667 if (D.getCXXScopeSpec().isSet()) { 4668 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4669 << D.getCXXScopeSpec().getRange(); 4670 New->setInvalidDecl(); 4671 } 4672 4673 // Add the parameter declaration into this scope. 4674 S->AddDecl(New); 4675 if (II) 4676 IdResolver.AddDecl(New); 4677 4678 ProcessDeclAttributes(S, New, D); 4679 4680 if (New->hasAttr<BlocksAttr>()) { 4681 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4682 } 4683 return New; 4684} 4685 4686/// \brief Synthesizes a variable for a parameter arising from a 4687/// typedef. 4688ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4689 SourceLocation Loc, 4690 QualType T) { 4691 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4692 T, Context.getTrivialTypeSourceInfo(T, Loc), 4693 SC_None, SC_None, 0); 4694 Param->setImplicit(); 4695 return Param; 4696} 4697 4698void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4699 ParmVarDecl * const *ParamEnd) { 4700 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4701 Diagnostic::Ignored) 4702 return; 4703 4704 // Don't diagnose unused-parameter errors in template instantiations; we 4705 // will already have done so in the template itself. 4706 if (!ActiveTemplateInstantiations.empty()) 4707 return; 4708 4709 for (; Param != ParamEnd; ++Param) { 4710 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4711 !(*Param)->hasAttr<UnusedAttr>()) { 4712 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4713 << (*Param)->getDeclName(); 4714 } 4715 } 4716} 4717 4718ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4719 TypeSourceInfo *TSInfo, QualType T, 4720 IdentifierInfo *Name, 4721 SourceLocation NameLoc, 4722 VarDecl::StorageClass StorageClass, 4723 VarDecl::StorageClass StorageClassAsWritten) { 4724 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4725 adjustParameterType(T), TSInfo, 4726 StorageClass, StorageClassAsWritten, 4727 0); 4728 4729 // Parameters can not be abstract class types. 4730 // For record types, this is done by the AbstractClassUsageDiagnoser once 4731 // the class has been completely parsed. 4732 if (!CurContext->isRecord() && 4733 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4734 AbstractParamType)) 4735 New->setInvalidDecl(); 4736 4737 // Parameter declarators cannot be interface types. All ObjC objects are 4738 // passed by reference. 4739 if (T->isObjCObjectType()) { 4740 Diag(NameLoc, 4741 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4742 New->setInvalidDecl(); 4743 } 4744 4745 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4746 // duration shall not be qualified by an address-space qualifier." 4747 // Since all parameters have automatic store duration, they can not have 4748 // an address space. 4749 if (T.getAddressSpace() != 0) { 4750 Diag(NameLoc, diag::err_arg_with_address_space); 4751 New->setInvalidDecl(); 4752 } 4753 4754 return New; 4755} 4756 4757void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4758 SourceLocation LocAfterDecls) { 4759 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4760 "Not a function declarator!"); 4761 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4762 4763 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4764 // for a K&R function. 4765 if (!FTI.hasPrototype) { 4766 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4767 --i; 4768 if (FTI.ArgInfo[i].Param == 0) { 4769 llvm::SmallString<256> Code; 4770 llvm::raw_svector_ostream(Code) << " int " 4771 << FTI.ArgInfo[i].Ident->getName() 4772 << ";\n"; 4773 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4774 << FTI.ArgInfo[i].Ident 4775 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4776 4777 // Implicitly declare the argument as type 'int' for lack of a better 4778 // type. 4779 DeclSpec DS; 4780 const char* PrevSpec; // unused 4781 unsigned DiagID; // unused 4782 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4783 PrevSpec, DiagID); 4784 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4785 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4786 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4787 } 4788 } 4789 } 4790} 4791 4792Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4793 Declarator &D) { 4794 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4795 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4796 "Not a function declarator!"); 4797 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4798 4799 if (FTI.hasPrototype) { 4800 // FIXME: Diagnose arguments without names in C. 4801 } 4802 4803 Scope *ParentScope = FnBodyScope->getParent(); 4804 4805 Decl *DP = HandleDeclarator(ParentScope, D, 4806 MultiTemplateParamsArg(*this), 4807 /*IsFunctionDefinition=*/true); 4808 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4809} 4810 4811static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4812 // Don't warn about invalid declarations. 4813 if (FD->isInvalidDecl()) 4814 return false; 4815 4816 // Or declarations that aren't global. 4817 if (!FD->isGlobal()) 4818 return false; 4819 4820 // Don't warn about C++ member functions. 4821 if (isa<CXXMethodDecl>(FD)) 4822 return false; 4823 4824 // Don't warn about 'main'. 4825 if (FD->isMain()) 4826 return false; 4827 4828 // Don't warn about inline functions. 4829 if (FD->isInlineSpecified()) 4830 return false; 4831 4832 // Don't warn about function templates. 4833 if (FD->getDescribedFunctionTemplate()) 4834 return false; 4835 4836 // Don't warn about function template specializations. 4837 if (FD->isFunctionTemplateSpecialization()) 4838 return false; 4839 4840 bool MissingPrototype = true; 4841 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4842 Prev; Prev = Prev->getPreviousDeclaration()) { 4843 // Ignore any declarations that occur in function or method 4844 // scope, because they aren't visible from the header. 4845 if (Prev->getDeclContext()->isFunctionOrMethod()) 4846 continue; 4847 4848 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4849 break; 4850 } 4851 4852 return MissingPrototype; 4853} 4854 4855Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4856 // Clear the last template instantiation error context. 4857 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4858 4859 if (!D) 4860 return D; 4861 FunctionDecl *FD = 0; 4862 4863 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4864 FD = FunTmpl->getTemplatedDecl(); 4865 else 4866 FD = cast<FunctionDecl>(D); 4867 4868 // Enter a new function scope 4869 PushFunctionScope(); 4870 4871 // See if this is a redefinition. 4872 // But don't complain if we're in GNU89 mode and the previous definition 4873 // was an extern inline function. 4874 const FunctionDecl *Definition; 4875 if (FD->hasBody(Definition) && 4876 !canRedefineFunction(Definition, getLangOptions())) { 4877 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 4878 Definition->getStorageClass() == SC_Extern) 4879 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 4880 << FD->getDeclName() << getLangOptions().CPlusPlus; 4881 else 4882 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4883 Diag(Definition->getLocation(), diag::note_previous_definition); 4884 } 4885 4886 // Builtin functions cannot be defined. 4887 if (unsigned BuiltinID = FD->getBuiltinID()) { 4888 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4889 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4890 FD->setInvalidDecl(); 4891 } 4892 } 4893 4894 // The return type of a function definition must be complete 4895 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4896 QualType ResultType = FD->getResultType(); 4897 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4898 !FD->isInvalidDecl() && 4899 RequireCompleteType(FD->getLocation(), ResultType, 4900 diag::err_func_def_incomplete_result)) 4901 FD->setInvalidDecl(); 4902 4903 // GNU warning -Wmissing-prototypes: 4904 // Warn if a global function is defined without a previous 4905 // prototype declaration. This warning is issued even if the 4906 // definition itself provides a prototype. The aim is to detect 4907 // global functions that fail to be declared in header files. 4908 if (ShouldWarnAboutMissingPrototype(FD)) 4909 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4910 4911 if (FnBodyScope) 4912 PushDeclContext(FnBodyScope, FD); 4913 4914 // Check the validity of our function parameters 4915 CheckParmsForFunctionDef(FD); 4916 4917 bool ShouldCheckShadow = 4918 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4919 4920 // Introduce our parameters into the function scope 4921 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4922 ParmVarDecl *Param = FD->getParamDecl(p); 4923 Param->setOwningFunction(FD); 4924 4925 // If this has an identifier, add it to the scope stack. 4926 if (Param->getIdentifier() && FnBodyScope) { 4927 if (ShouldCheckShadow) 4928 CheckShadow(FnBodyScope, Param); 4929 4930 PushOnScopeChains(Param, FnBodyScope); 4931 } 4932 } 4933 4934 // Checking attributes of current function definition 4935 // dllimport attribute. 4936 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 4937 if (DA && (!FD->getAttr<DLLExportAttr>())) { 4938 // dllimport attribute cannot be directly applied to definition. 4939 if (!DA->isInherited()) { 4940 Diag(FD->getLocation(), 4941 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4942 << "dllimport"; 4943 FD->setInvalidDecl(); 4944 return FD; 4945 } 4946 4947 // Visual C++ appears to not think this is an issue, so only issue 4948 // a warning when Microsoft extensions are disabled. 4949 if (!LangOpts.Microsoft) { 4950 // If a symbol previously declared dllimport is later defined, the 4951 // attribute is ignored in subsequent references, and a warning is 4952 // emitted. 4953 Diag(FD->getLocation(), 4954 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4955 << FD->getName() << "dllimport"; 4956 } 4957 } 4958 return FD; 4959} 4960 4961/// \brief Given the set of return statements within a function body, 4962/// compute the variables that are subject to the named return value 4963/// optimization. 4964/// 4965/// Each of the variables that is subject to the named return value 4966/// optimization will be marked as NRVO variables in the AST, and any 4967/// return statement that has a marked NRVO variable as its NRVO candidate can 4968/// use the named return value optimization. 4969/// 4970/// This function applies a very simplistic algorithm for NRVO: if every return 4971/// statement in the function has the same NRVO candidate, that candidate is 4972/// the NRVO variable. 4973/// 4974/// FIXME: Employ a smarter algorithm that accounts for multiple return 4975/// statements and the lifetimes of the NRVO candidates. We should be able to 4976/// find a maximal set of NRVO variables. 4977static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 4978 ReturnStmt **Returns = Scope->Returns.data(); 4979 4980 const VarDecl *NRVOCandidate = 0; 4981 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 4982 if (!Returns[I]->getNRVOCandidate()) 4983 return; 4984 4985 if (!NRVOCandidate) 4986 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4987 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4988 return; 4989 } 4990 4991 if (NRVOCandidate) 4992 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4993} 4994 4995Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 4996 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4997} 4998 4999Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5000 bool IsInstantiation) { 5001 FunctionDecl *FD = 0; 5002 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5003 if (FunTmpl) 5004 FD = FunTmpl->getTemplatedDecl(); 5005 else 5006 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5007 5008 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5009 5010 if (FD) { 5011 FD->setBody(Body); 5012 if (FD->isMain()) { 5013 // C and C++ allow for main to automagically return 0. 5014 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5015 FD->setHasImplicitReturnZero(true); 5016 WP.disableCheckFallThrough(); 5017 } 5018 5019 if (!FD->isInvalidDecl()) { 5020 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5021 5022 // If this is a constructor, we need a vtable. 5023 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5024 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5025 5026 ComputeNRVO(Body, getCurFunction()); 5027 } 5028 5029 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5030 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5031 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5032 MD->setBody(Body); 5033 MD->setEndLoc(Body->getLocEnd()); 5034 if (!MD->isInvalidDecl()) 5035 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5036 } else { 5037 return 0; 5038 } 5039 5040 // Verify and clean out per-function state. 5041 5042 // Check goto/label use. 5043 FunctionScopeInfo *CurFn = getCurFunction(); 5044 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5045 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5046 LabelStmt *L = I->second; 5047 5048 // Verify that we have no forward references left. If so, there was a goto 5049 // or address of a label taken, but no definition of it. Label fwd 5050 // definitions are indicated with a null substmt. 5051 if (L->getSubStmt() != 0) { 5052 if (!L->isUsed()) 5053 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5054 continue; 5055 } 5056 5057 // Emit error. 5058 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5059 5060 // At this point, we have gotos that use the bogus label. Stitch it into 5061 // the function body so that they aren't leaked and that the AST is well 5062 // formed. 5063 if (Body == 0) { 5064 // The whole function wasn't parsed correctly. 5065 continue; 5066 } 5067 5068 // Otherwise, the body is valid: we want to stitch the label decl into the 5069 // function somewhere so that it is properly owned and so that the goto 5070 // has a valid target. Do this by creating a new compound stmt with the 5071 // label in it. 5072 5073 // Give the label a sub-statement. 5074 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5075 5076 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5077 cast<CXXTryStmt>(Body)->getTryBlock() : 5078 cast<CompoundStmt>(Body); 5079 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5080 Compound->body_end()); 5081 Elements.push_back(L); 5082 Compound->setStmts(Context, Elements.data(), Elements.size()); 5083 } 5084 5085 if (Body) { 5086 // C++ constructors that have function-try-blocks can't have return 5087 // statements in the handlers of that block. (C++ [except.handle]p14) 5088 // Verify this. 5089 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5090 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5091 5092 // Verify that that gotos and switch cases don't jump into scopes illegally. 5093 // Verify that that gotos and switch cases don't jump into scopes illegally. 5094 if (getCurFunction()->NeedsScopeChecking() && 5095 !dcl->isInvalidDecl() && 5096 !hasAnyErrorsInThisFunction()) 5097 DiagnoseInvalidJumps(Body); 5098 5099 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5100 if (!Destructor->getParent()->isDependentType()) 5101 CheckDestructor(Destructor); 5102 5103 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5104 Destructor->getParent()); 5105 } 5106 5107 // If any errors have occurred, clear out any temporaries that may have 5108 // been leftover. This ensures that these temporaries won't be picked up for 5109 // deletion in some later function. 5110 if (PP.getDiagnostics().hasErrorOccurred()) 5111 ExprTemporaries.clear(); 5112 else if (!isa<FunctionTemplateDecl>(dcl)) { 5113 // Since the body is valid, issue any analysis-based warnings that are 5114 // enabled. 5115 QualType ResultType; 5116 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5117 AnalysisWarnings.IssueWarnings(WP, FD); 5118 } else { 5119 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5120 AnalysisWarnings.IssueWarnings(WP, MD); 5121 } 5122 } 5123 5124 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5125 } 5126 5127 if (!IsInstantiation) 5128 PopDeclContext(); 5129 5130 PopFunctionOrBlockScope(); 5131 5132 // If any errors have occurred, clear out any temporaries that may have 5133 // been leftover. This ensures that these temporaries won't be picked up for 5134 // deletion in some later function. 5135 if (getDiagnostics().hasErrorOccurred()) 5136 ExprTemporaries.clear(); 5137 5138 return dcl; 5139} 5140 5141/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5142/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5143NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5144 IdentifierInfo &II, Scope *S) { 5145 // Before we produce a declaration for an implicitly defined 5146 // function, see whether there was a locally-scoped declaration of 5147 // this name as a function or variable. If so, use that 5148 // (non-visible) declaration, and complain about it. 5149 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5150 = LocallyScopedExternalDecls.find(&II); 5151 if (Pos != LocallyScopedExternalDecls.end()) { 5152 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5153 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5154 return Pos->second; 5155 } 5156 5157 // Extension in C99. Legal in C90, but warn about it. 5158 if (II.getName().startswith("__builtin_")) 5159 Diag(Loc, diag::warn_builtin_unknown) << &II; 5160 else if (getLangOptions().C99) 5161 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5162 else 5163 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5164 5165 // Set a Declarator for the implicit definition: int foo(); 5166 const char *Dummy; 5167 DeclSpec DS; 5168 unsigned DiagID; 5169 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5170 Error = Error; // Silence warning. 5171 assert(!Error && "Error setting up implicit decl!"); 5172 Declarator D(DS, Declarator::BlockContext); 5173 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5174 0, 0, false, SourceLocation(), 5175 false, 0,0,0, Loc, Loc, D), 5176 SourceLocation()); 5177 D.SetIdentifier(&II, Loc); 5178 5179 // Insert this function into translation-unit scope. 5180 5181 DeclContext *PrevDC = CurContext; 5182 CurContext = Context.getTranslationUnitDecl(); 5183 5184 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5185 FD->setImplicit(); 5186 5187 CurContext = PrevDC; 5188 5189 AddKnownFunctionAttributes(FD); 5190 5191 return FD; 5192} 5193 5194/// \brief Adds any function attributes that we know a priori based on 5195/// the declaration of this function. 5196/// 5197/// These attributes can apply both to implicitly-declared builtins 5198/// (like __builtin___printf_chk) or to library-declared functions 5199/// like NSLog or printf. 5200void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5201 if (FD->isInvalidDecl()) 5202 return; 5203 5204 // If this is a built-in function, map its builtin attributes to 5205 // actual attributes. 5206 if (unsigned BuiltinID = FD->getBuiltinID()) { 5207 // Handle printf-formatting attributes. 5208 unsigned FormatIdx; 5209 bool HasVAListArg; 5210 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5211 if (!FD->getAttr<FormatAttr>()) 5212 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5213 "printf", FormatIdx+1, 5214 HasVAListArg ? 0 : FormatIdx+2)); 5215 } 5216 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5217 HasVAListArg)) { 5218 if (!FD->getAttr<FormatAttr>()) 5219 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5220 "scanf", FormatIdx+1, 5221 HasVAListArg ? 0 : FormatIdx+2)); 5222 } 5223 5224 // Mark const if we don't care about errno and that is the only 5225 // thing preventing the function from being const. This allows 5226 // IRgen to use LLVM intrinsics for such functions. 5227 if (!getLangOptions().MathErrno && 5228 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5229 if (!FD->getAttr<ConstAttr>()) 5230 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5231 } 5232 5233 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5234 FD->setType(Context.getNoReturnType(FD->getType())); 5235 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5236 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5237 if (Context.BuiltinInfo.isConst(BuiltinID)) 5238 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5239 } 5240 5241 IdentifierInfo *Name = FD->getIdentifier(); 5242 if (!Name) 5243 return; 5244 if ((!getLangOptions().CPlusPlus && 5245 FD->getDeclContext()->isTranslationUnit()) || 5246 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5247 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5248 LinkageSpecDecl::lang_c)) { 5249 // Okay: this could be a libc/libm/Objective-C function we know 5250 // about. 5251 } else 5252 return; 5253 5254 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5255 // FIXME: NSLog and NSLogv should be target specific 5256 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5257 // FIXME: We known better than our headers. 5258 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5259 } else 5260 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5261 "printf", 1, 5262 Name->isStr("NSLogv") ? 0 : 2)); 5263 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5264 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5265 // target-specific builtins, perhaps? 5266 if (!FD->getAttr<FormatAttr>()) 5267 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5268 "printf", 2, 5269 Name->isStr("vasprintf") ? 0 : 3)); 5270 } 5271} 5272 5273TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5274 TypeSourceInfo *TInfo) { 5275 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5276 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5277 5278 if (!TInfo) { 5279 assert(D.isInvalidType() && "no declarator info for valid type"); 5280 TInfo = Context.getTrivialTypeSourceInfo(T); 5281 } 5282 5283 // Scope manipulation handled by caller. 5284 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5285 D.getIdentifierLoc(), 5286 D.getIdentifier(), 5287 TInfo); 5288 5289 if (const TagType *TT = T->getAs<TagType>()) { 5290 TagDecl *TD = TT->getDecl(); 5291 5292 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5293 // keep track of the TypedefDecl. 5294 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5295 TD->setTypedefForAnonDecl(NewTD); 5296 } 5297 5298 if (D.isInvalidType()) 5299 NewTD->setInvalidDecl(); 5300 return NewTD; 5301} 5302 5303 5304/// \brief Determine whether a tag with a given kind is acceptable 5305/// as a redeclaration of the given tag declaration. 5306/// 5307/// \returns true if the new tag kind is acceptable, false otherwise. 5308bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5309 TagTypeKind NewTag, 5310 SourceLocation NewTagLoc, 5311 const IdentifierInfo &Name) { 5312 // C++ [dcl.type.elab]p3: 5313 // The class-key or enum keyword present in the 5314 // elaborated-type-specifier shall agree in kind with the 5315 // declaration to which the name in the elaborated-type-specifier 5316 // refers. This rule also applies to the form of 5317 // elaborated-type-specifier that declares a class-name or 5318 // friend class since it can be construed as referring to the 5319 // definition of the class. Thus, in any 5320 // elaborated-type-specifier, the enum keyword shall be used to 5321 // refer to an enumeration (7.2), the union class-key shall be 5322 // used to refer to a union (clause 9), and either the class or 5323 // struct class-key shall be used to refer to a class (clause 9) 5324 // declared using the class or struct class-key. 5325 TagTypeKind OldTag = Previous->getTagKind(); 5326 if (OldTag == NewTag) 5327 return true; 5328 5329 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5330 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5331 // Warn about the struct/class tag mismatch. 5332 bool isTemplate = false; 5333 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5334 isTemplate = Record->getDescribedClassTemplate(); 5335 5336 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5337 << (NewTag == TTK_Class) 5338 << isTemplate << &Name 5339 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5340 OldTag == TTK_Class? "class" : "struct"); 5341 Diag(Previous->getLocation(), diag::note_previous_use); 5342 return true; 5343 } 5344 return false; 5345} 5346 5347/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5348/// former case, Name will be non-null. In the later case, Name will be null. 5349/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5350/// reference/declaration/definition of a tag. 5351Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5352 SourceLocation KWLoc, CXXScopeSpec &SS, 5353 IdentifierInfo *Name, SourceLocation NameLoc, 5354 AttributeList *Attr, AccessSpecifier AS, 5355 MultiTemplateParamsArg TemplateParameterLists, 5356 bool &OwnedDecl, bool &IsDependent, bool ScopedEnum, 5357 TypeResult UnderlyingType) { 5358 // If this is not a definition, it must have a name. 5359 assert((Name != 0 || TUK == TUK_Definition) && 5360 "Nameless record must be a definition!"); 5361 5362 OwnedDecl = false; 5363 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5364 5365 // FIXME: Check explicit specializations more carefully. 5366 bool isExplicitSpecialization = false; 5367 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5368 bool Invalid = false; 5369 if (TUK != TUK_Reference) { 5370 if (TemplateParameterList *TemplateParams 5371 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5372 (TemplateParameterList**)TemplateParameterLists.get(), 5373 TemplateParameterLists.size(), 5374 TUK == TUK_Friend, 5375 isExplicitSpecialization, 5376 Invalid)) { 5377 // All but one template parameter lists have been matching. 5378 --NumMatchedTemplateParamLists; 5379 5380 if (TemplateParams->size() > 0) { 5381 // This is a declaration or definition of a class template (which may 5382 // be a member of another template). 5383 if (Invalid) 5384 return 0; 5385 5386 OwnedDecl = false; 5387 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5388 SS, Name, NameLoc, Attr, 5389 TemplateParams, 5390 AS); 5391 TemplateParameterLists.release(); 5392 return Result.get(); 5393 } else { 5394 // The "template<>" header is extraneous. 5395 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5396 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5397 isExplicitSpecialization = true; 5398 } 5399 } 5400 } 5401 5402 // Figure out the underlying type if this a enum declaration. We need to do 5403 // this early, because it's needed to detect if this is an incompatible 5404 // redeclaration. 5405 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 5406 5407 if (Kind == TTK_Enum) { 5408 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 5409 // No underlying type explicitly specified, or we failed to parse the 5410 // type, default to int. 5411 EnumUnderlying = Context.IntTy.getTypePtr(); 5412 else if (UnderlyingType.get()) { 5413 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 5414 // integral type; any cv-qualification is ignored. 5415 TypeSourceInfo *TI = 0; 5416 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 5417 EnumUnderlying = TI; 5418 5419 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 5420 5421 if (!T->isDependentType() && !T->isIntegralType(Context)) { 5422 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 5423 << T; 5424 // Recover by falling back to int. 5425 EnumUnderlying = Context.IntTy.getTypePtr(); 5426 } 5427 } 5428 } 5429 5430 DeclContext *SearchDC = CurContext; 5431 DeclContext *DC = CurContext; 5432 bool isStdBadAlloc = false; 5433 5434 RedeclarationKind Redecl = ForRedeclaration; 5435 if (TUK == TUK_Friend || TUK == TUK_Reference) 5436 Redecl = NotForRedeclaration; 5437 5438 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5439 5440 if (Name && SS.isNotEmpty()) { 5441 // We have a nested-name tag ('struct foo::bar'). 5442 5443 // Check for invalid 'foo::'. 5444 if (SS.isInvalid()) { 5445 Name = 0; 5446 goto CreateNewDecl; 5447 } 5448 5449 // If this is a friend or a reference to a class in a dependent 5450 // context, don't try to make a decl for it. 5451 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5452 DC = computeDeclContext(SS, false); 5453 if (!DC) { 5454 IsDependent = true; 5455 return 0; 5456 } 5457 } else { 5458 DC = computeDeclContext(SS, true); 5459 if (!DC) { 5460 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5461 << SS.getRange(); 5462 return 0; 5463 } 5464 } 5465 5466 if (RequireCompleteDeclContext(SS, DC)) 5467 return 0; 5468 5469 SearchDC = DC; 5470 // Look-up name inside 'foo::'. 5471 LookupQualifiedName(Previous, DC); 5472 5473 if (Previous.isAmbiguous()) 5474 return 0; 5475 5476 if (Previous.empty()) { 5477 // Name lookup did not find anything. However, if the 5478 // nested-name-specifier refers to the current instantiation, 5479 // and that current instantiation has any dependent base 5480 // classes, we might find something at instantiation time: treat 5481 // this as a dependent elaborated-type-specifier. 5482 if (Previous.wasNotFoundInCurrentInstantiation()) { 5483 IsDependent = true; 5484 return 0; 5485 } 5486 5487 // A tag 'foo::bar' must already exist. 5488 Diag(NameLoc, diag::err_not_tag_in_scope) 5489 << Kind << Name << DC << SS.getRange(); 5490 Name = 0; 5491 Invalid = true; 5492 goto CreateNewDecl; 5493 } 5494 } else if (Name) { 5495 // If this is a named struct, check to see if there was a previous forward 5496 // declaration or definition. 5497 // FIXME: We're looking into outer scopes here, even when we 5498 // shouldn't be. Doing so can result in ambiguities that we 5499 // shouldn't be diagnosing. 5500 LookupName(Previous, S); 5501 5502 // Note: there used to be some attempt at recovery here. 5503 if (Previous.isAmbiguous()) 5504 return 0; 5505 5506 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5507 // FIXME: This makes sure that we ignore the contexts associated 5508 // with C structs, unions, and enums when looking for a matching 5509 // tag declaration or definition. See the similar lookup tweak 5510 // in Sema::LookupName; is there a better way to deal with this? 5511 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5512 SearchDC = SearchDC->getParent(); 5513 } 5514 } else if (S->isFunctionPrototypeScope()) { 5515 // If this is an enum declaration in function prototype scope, set its 5516 // initial context to the translation unit. 5517 SearchDC = Context.getTranslationUnitDecl(); 5518 } 5519 5520 if (Previous.isSingleResult() && 5521 Previous.getFoundDecl()->isTemplateParameter()) { 5522 // Maybe we will complain about the shadowed template parameter. 5523 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5524 // Just pretend that we didn't see the previous declaration. 5525 Previous.clear(); 5526 } 5527 5528 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5529 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5530 // This is a declaration of or a reference to "std::bad_alloc". 5531 isStdBadAlloc = true; 5532 5533 if (Previous.empty() && StdBadAlloc) { 5534 // std::bad_alloc has been implicitly declared (but made invisible to 5535 // name lookup). Fill in this implicit declaration as the previous 5536 // declaration, so that the declarations get chained appropriately. 5537 Previous.addDecl(getStdBadAlloc()); 5538 } 5539 } 5540 5541 // If we didn't find a previous declaration, and this is a reference 5542 // (or friend reference), move to the correct scope. In C++, we 5543 // also need to do a redeclaration lookup there, just in case 5544 // there's a shadow friend decl. 5545 if (Name && Previous.empty() && 5546 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5547 if (Invalid) goto CreateNewDecl; 5548 assert(SS.isEmpty()); 5549 5550 if (TUK == TUK_Reference) { 5551 // C++ [basic.scope.pdecl]p5: 5552 // -- for an elaborated-type-specifier of the form 5553 // 5554 // class-key identifier 5555 // 5556 // if the elaborated-type-specifier is used in the 5557 // decl-specifier-seq or parameter-declaration-clause of a 5558 // function defined in namespace scope, the identifier is 5559 // declared as a class-name in the namespace that contains 5560 // the declaration; otherwise, except as a friend 5561 // declaration, the identifier is declared in the smallest 5562 // non-class, non-function-prototype scope that contains the 5563 // declaration. 5564 // 5565 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5566 // C structs and unions. 5567 // 5568 // It is an error in C++ to declare (rather than define) an enum 5569 // type, including via an elaborated type specifier. We'll 5570 // diagnose that later; for now, declare the enum in the same 5571 // scope as we would have picked for any other tag type. 5572 // 5573 // GNU C also supports this behavior as part of its incomplete 5574 // enum types extension, while GNU C++ does not. 5575 // 5576 // Find the context where we'll be declaring the tag. 5577 // FIXME: We would like to maintain the current DeclContext as the 5578 // lexical context, 5579 while (SearchDC->isRecord()) 5580 SearchDC = SearchDC->getParent(); 5581 5582 // Find the scope where we'll be declaring the tag. 5583 while (S->isClassScope() || 5584 (getLangOptions().CPlusPlus && 5585 S->isFunctionPrototypeScope()) || 5586 ((S->getFlags() & Scope::DeclScope) == 0) || 5587 (S->getEntity() && 5588 ((DeclContext *)S->getEntity())->isTransparentContext())) 5589 S = S->getParent(); 5590 } else { 5591 assert(TUK == TUK_Friend); 5592 // C++ [namespace.memdef]p3: 5593 // If a friend declaration in a non-local class first declares a 5594 // class or function, the friend class or function is a member of 5595 // the innermost enclosing namespace. 5596 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5597 } 5598 5599 // In C++, we need to do a redeclaration lookup to properly 5600 // diagnose some problems. 5601 if (getLangOptions().CPlusPlus) { 5602 Previous.setRedeclarationKind(ForRedeclaration); 5603 LookupQualifiedName(Previous, SearchDC); 5604 } 5605 } 5606 5607 if (!Previous.empty()) { 5608 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5609 5610 // It's okay to have a tag decl in the same scope as a typedef 5611 // which hides a tag decl in the same scope. Finding this 5612 // insanity with a redeclaration lookup can only actually happen 5613 // in C++. 5614 // 5615 // This is also okay for elaborated-type-specifiers, which is 5616 // technically forbidden by the current standard but which is 5617 // okay according to the likely resolution of an open issue; 5618 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5619 if (getLangOptions().CPlusPlus) { 5620 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5621 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5622 TagDecl *Tag = TT->getDecl(); 5623 if (Tag->getDeclName() == Name && 5624 Tag->getDeclContext()->getRedeclContext() 5625 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5626 PrevDecl = Tag; 5627 Previous.clear(); 5628 Previous.addDecl(Tag); 5629 Previous.resolveKind(); 5630 } 5631 } 5632 } 5633 } 5634 5635 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5636 // If this is a use of a previous tag, or if the tag is already declared 5637 // in the same scope (so that the definition/declaration completes or 5638 // rementions the tag), reuse the decl. 5639 if (TUK == TUK_Reference || TUK == TUK_Friend || 5640 isDeclInScope(PrevDecl, SearchDC, S)) { 5641 // Make sure that this wasn't declared as an enum and now used as a 5642 // struct or something similar. 5643 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5644 bool SafeToContinue 5645 = (PrevTagDecl->getTagKind() != TTK_Enum && 5646 Kind != TTK_Enum); 5647 if (SafeToContinue) 5648 Diag(KWLoc, diag::err_use_with_wrong_tag) 5649 << Name 5650 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5651 PrevTagDecl->getKindName()); 5652 else 5653 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5654 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5655 5656 if (SafeToContinue) 5657 Kind = PrevTagDecl->getTagKind(); 5658 else { 5659 // Recover by making this an anonymous redefinition. 5660 Name = 0; 5661 Previous.clear(); 5662 Invalid = true; 5663 } 5664 } 5665 5666 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 5667 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 5668 5669 // All conflicts with previous declarations are recovered by 5670 // returning the previous declaration. 5671 if (ScopedEnum != PrevEnum->isScoped()) { 5672 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 5673 << PrevEnum->isScoped(); 5674 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5675 return PrevTagDecl; 5676 } 5677 else if (EnumUnderlying && PrevEnum->isFixed()) { 5678 QualType T; 5679 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5680 T = TI->getType(); 5681 else 5682 T = QualType(EnumUnderlying.get<const Type*>(), 0); 5683 5684 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 5685 Diag(KWLoc, diag::err_enum_redeclare_type_mismatch); 5686 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5687 return PrevTagDecl; 5688 } 5689 } 5690 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 5691 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 5692 << PrevEnum->isFixed(); 5693 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5694 return PrevTagDecl; 5695 } 5696 } 5697 5698 if (!Invalid) { 5699 // If this is a use, just return the declaration we found. 5700 5701 // FIXME: In the future, return a variant or some other clue 5702 // for the consumer of this Decl to know it doesn't own it. 5703 // For our current ASTs this shouldn't be a problem, but will 5704 // need to be changed with DeclGroups. 5705 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5706 TUK == TUK_Friend) 5707 return PrevTagDecl; 5708 5709 // Diagnose attempts to redefine a tag. 5710 if (TUK == TUK_Definition) { 5711 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5712 // If we're defining a specialization and the previous definition 5713 // is from an implicit instantiation, don't emit an error 5714 // here; we'll catch this in the general case below. 5715 if (!isExplicitSpecialization || 5716 !isa<CXXRecordDecl>(Def) || 5717 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5718 == TSK_ExplicitSpecialization) { 5719 Diag(NameLoc, diag::err_redefinition) << Name; 5720 Diag(Def->getLocation(), diag::note_previous_definition); 5721 // If this is a redefinition, recover by making this 5722 // struct be anonymous, which will make any later 5723 // references get the previous definition. 5724 Name = 0; 5725 Previous.clear(); 5726 Invalid = true; 5727 } 5728 } else { 5729 // If the type is currently being defined, complain 5730 // about a nested redefinition. 5731 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5732 if (Tag->isBeingDefined()) { 5733 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5734 Diag(PrevTagDecl->getLocation(), 5735 diag::note_previous_definition); 5736 Name = 0; 5737 Previous.clear(); 5738 Invalid = true; 5739 } 5740 } 5741 5742 // Okay, this is definition of a previously declared or referenced 5743 // tag PrevDecl. We're going to create a new Decl for it. 5744 } 5745 } 5746 // If we get here we have (another) forward declaration or we 5747 // have a definition. Just create a new decl. 5748 5749 } else { 5750 // If we get here, this is a definition of a new tag type in a nested 5751 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5752 // new decl/type. We set PrevDecl to NULL so that the entities 5753 // have distinct types. 5754 Previous.clear(); 5755 } 5756 // If we get here, we're going to create a new Decl. If PrevDecl 5757 // is non-NULL, it's a definition of the tag declared by 5758 // PrevDecl. If it's NULL, we have a new definition. 5759 5760 5761 // Otherwise, PrevDecl is not a tag, but was found with tag 5762 // lookup. This is only actually possible in C++, where a few 5763 // things like templates still live in the tag namespace. 5764 } else { 5765 assert(getLangOptions().CPlusPlus); 5766 5767 // Use a better diagnostic if an elaborated-type-specifier 5768 // found the wrong kind of type on the first 5769 // (non-redeclaration) lookup. 5770 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5771 !Previous.isForRedeclaration()) { 5772 unsigned Kind = 0; 5773 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5774 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5775 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5776 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5777 Invalid = true; 5778 5779 // Otherwise, only diagnose if the declaration is in scope. 5780 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5781 // do nothing 5782 5783 // Diagnose implicit declarations introduced by elaborated types. 5784 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5785 unsigned Kind = 0; 5786 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5787 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5788 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5789 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5790 Invalid = true; 5791 5792 // Otherwise it's a declaration. Call out a particularly common 5793 // case here. 5794 } else if (isa<TypedefDecl>(PrevDecl)) { 5795 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5796 << Name 5797 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5798 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5799 Invalid = true; 5800 5801 // Otherwise, diagnose. 5802 } else { 5803 // The tag name clashes with something else in the target scope, 5804 // issue an error and recover by making this tag be anonymous. 5805 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5806 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5807 Name = 0; 5808 Invalid = true; 5809 } 5810 5811 // The existing declaration isn't relevant to us; we're in a 5812 // new scope, so clear out the previous declaration. 5813 Previous.clear(); 5814 } 5815 } 5816 5817CreateNewDecl: 5818 5819 TagDecl *PrevDecl = 0; 5820 if (Previous.isSingleResult()) 5821 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5822 5823 // If there is an identifier, use the location of the identifier as the 5824 // location of the decl, otherwise use the location of the struct/union 5825 // keyword. 5826 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5827 5828 // Otherwise, create a new declaration. If there is a previous 5829 // declaration of the same entity, the two will be linked via 5830 // PrevDecl. 5831 TagDecl *New; 5832 5833 bool IsForwardReference = false; 5834 if (Kind == TTK_Enum) { 5835 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5836 // enum X { A, B, C } D; D should chain to X. 5837 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5838 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 5839 !EnumUnderlying.isNull()); 5840 // If this is an undefined enum, warn. 5841 if (TUK != TUK_Definition && !Invalid) { 5842 TagDecl *Def; 5843 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 5844 // C++0x: 7.2p2: opaque-enum-declaration. 5845 // Conflicts are diagnosed above. Do nothing. 5846 } 5847 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5848 Diag(Loc, diag::ext_forward_ref_enum_def) 5849 << New; 5850 Diag(Def->getLocation(), diag::note_previous_definition); 5851 } else { 5852 unsigned DiagID = diag::ext_forward_ref_enum; 5853 if (getLangOptions().Microsoft) 5854 DiagID = diag::ext_ms_forward_ref_enum; 5855 else if (getLangOptions().CPlusPlus) 5856 DiagID = diag::err_forward_ref_enum; 5857 Diag(Loc, DiagID); 5858 5859 // If this is a forward-declared reference to an enumeration, make a 5860 // note of it; we won't actually be introducing the declaration into 5861 // the declaration context. 5862 if (TUK == TUK_Reference) 5863 IsForwardReference = true; 5864 } 5865 } 5866 5867 if (EnumUnderlying) { 5868 EnumDecl *ED = cast<EnumDecl>(New); 5869 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5870 ED->setIntegerTypeSourceInfo(TI); 5871 else 5872 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 5873 ED->setPromotionType(ED->getIntegerType()); 5874 } 5875 5876 } else { 5877 // struct/union/class 5878 5879 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5880 // struct X { int A; } D; D should chain to X. 5881 if (getLangOptions().CPlusPlus) { 5882 // FIXME: Look for a way to use RecordDecl for simple structs. 5883 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5884 cast_or_null<CXXRecordDecl>(PrevDecl)); 5885 5886 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5887 StdBadAlloc = cast<CXXRecordDecl>(New); 5888 } else 5889 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5890 cast_or_null<RecordDecl>(PrevDecl)); 5891 } 5892 5893 // Maybe add qualifier info. 5894 if (SS.isNotEmpty()) { 5895 if (SS.isSet()) { 5896 NestedNameSpecifier *NNS 5897 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5898 New->setQualifierInfo(NNS, SS.getRange()); 5899 if (NumMatchedTemplateParamLists > 0) { 5900 New->setTemplateParameterListsInfo(Context, 5901 NumMatchedTemplateParamLists, 5902 (TemplateParameterList**) TemplateParameterLists.release()); 5903 } 5904 } 5905 else 5906 Invalid = true; 5907 } 5908 5909 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5910 // Add alignment attributes if necessary; these attributes are checked when 5911 // the ASTContext lays out the structure. 5912 // 5913 // It is important for implementing the correct semantics that this 5914 // happen here (in act on tag decl). The #pragma pack stack is 5915 // maintained as a result of parser callbacks which can occur at 5916 // many points during the parsing of a struct declaration (because 5917 // the #pragma tokens are effectively skipped over during the 5918 // parsing of the struct). 5919 AddAlignmentAttributesForRecord(RD); 5920 } 5921 5922 // If this is a specialization of a member class (of a class template), 5923 // check the specialization. 5924 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5925 Invalid = true; 5926 5927 if (Invalid) 5928 New->setInvalidDecl(); 5929 5930 if (Attr) 5931 ProcessDeclAttributeList(S, New, Attr); 5932 5933 // If we're declaring or defining a tag in function prototype scope 5934 // in C, note that this type can only be used within the function. 5935 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5936 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5937 5938 // Set the lexical context. If the tag has a C++ scope specifier, the 5939 // lexical context will be different from the semantic context. 5940 New->setLexicalDeclContext(CurContext); 5941 5942 // Mark this as a friend decl if applicable. 5943 if (TUK == TUK_Friend) 5944 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5945 5946 // Set the access specifier. 5947 if (!Invalid && SearchDC->isRecord()) 5948 SetMemberAccessSpecifier(New, PrevDecl, AS); 5949 5950 if (TUK == TUK_Definition) 5951 New->startDefinition(); 5952 5953 // If this has an identifier, add it to the scope stack. 5954 if (TUK == TUK_Friend) { 5955 // We might be replacing an existing declaration in the lookup tables; 5956 // if so, borrow its access specifier. 5957 if (PrevDecl) 5958 New->setAccess(PrevDecl->getAccess()); 5959 5960 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 5961 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5962 if (Name) // can be null along some error paths 5963 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5964 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5965 } else if (Name) { 5966 S = getNonFieldDeclScope(S); 5967 PushOnScopeChains(New, S, !IsForwardReference); 5968 if (IsForwardReference) 5969 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5970 5971 } else { 5972 CurContext->addDecl(New); 5973 } 5974 5975 // If this is the C FILE type, notify the AST context. 5976 if (IdentifierInfo *II = New->getIdentifier()) 5977 if (!New->isInvalidDecl() && 5978 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 5979 II->isStr("FILE")) 5980 Context.setFILEDecl(New); 5981 5982 OwnedDecl = true; 5983 return New; 5984} 5985 5986void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 5987 AdjustDeclIfTemplate(TagD); 5988 TagDecl *Tag = cast<TagDecl>(TagD); 5989 5990 // Enter the tag context. 5991 PushDeclContext(S, Tag); 5992} 5993 5994void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 5995 SourceLocation LBraceLoc) { 5996 AdjustDeclIfTemplate(TagD); 5997 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 5998 5999 FieldCollector->StartClass(); 6000 6001 if (!Record->getIdentifier()) 6002 return; 6003 6004 // C++ [class]p2: 6005 // [...] The class-name is also inserted into the scope of the 6006 // class itself; this is known as the injected-class-name. For 6007 // purposes of access checking, the injected-class-name is treated 6008 // as if it were a public member name. 6009 CXXRecordDecl *InjectedClassName 6010 = CXXRecordDecl::Create(Context, Record->getTagKind(), 6011 CurContext, Record->getLocation(), 6012 Record->getIdentifier(), 6013 Record->getTagKeywordLoc(), 6014 Record); 6015 InjectedClassName->setImplicit(); 6016 InjectedClassName->setAccess(AS_public); 6017 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6018 InjectedClassName->setDescribedClassTemplate(Template); 6019 PushOnScopeChains(InjectedClassName, S); 6020 assert(InjectedClassName->isInjectedClassName() && 6021 "Broken injected-class-name"); 6022} 6023 6024void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6025 SourceLocation RBraceLoc) { 6026 AdjustDeclIfTemplate(TagD); 6027 TagDecl *Tag = cast<TagDecl>(TagD); 6028 Tag->setRBraceLoc(RBraceLoc); 6029 6030 if (isa<CXXRecordDecl>(Tag)) 6031 FieldCollector->FinishClass(); 6032 6033 // Exit this scope of this tag's definition. 6034 PopDeclContext(); 6035 6036 // Notify the consumer that we've defined a tag. 6037 Consumer.HandleTagDeclDefinition(Tag); 6038} 6039 6040void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6041 AdjustDeclIfTemplate(TagD); 6042 TagDecl *Tag = cast<TagDecl>(TagD); 6043 Tag->setInvalidDecl(); 6044 6045 // We're undoing ActOnTagStartDefinition here, not 6046 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6047 // the FieldCollector. 6048 6049 PopDeclContext(); 6050} 6051 6052// Note that FieldName may be null for anonymous bitfields. 6053bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6054 QualType FieldTy, const Expr *BitWidth, 6055 bool *ZeroWidth) { 6056 // Default to true; that shouldn't confuse checks for emptiness 6057 if (ZeroWidth) 6058 *ZeroWidth = true; 6059 6060 // C99 6.7.2.1p4 - verify the field type. 6061 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6062 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6063 // Handle incomplete types with specific error. 6064 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6065 return true; 6066 if (FieldName) 6067 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6068 << FieldName << FieldTy << BitWidth->getSourceRange(); 6069 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6070 << FieldTy << BitWidth->getSourceRange(); 6071 } 6072 6073 // If the bit-width is type- or value-dependent, don't try to check 6074 // it now. 6075 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6076 return false; 6077 6078 llvm::APSInt Value; 6079 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6080 return true; 6081 6082 if (Value != 0 && ZeroWidth) 6083 *ZeroWidth = false; 6084 6085 // Zero-width bitfield is ok for anonymous field. 6086 if (Value == 0 && FieldName) 6087 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6088 6089 if (Value.isSigned() && Value.isNegative()) { 6090 if (FieldName) 6091 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6092 << FieldName << Value.toString(10); 6093 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6094 << Value.toString(10); 6095 } 6096 6097 if (!FieldTy->isDependentType()) { 6098 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6099 if (Value.getZExtValue() > TypeSize) { 6100 if (!getLangOptions().CPlusPlus) { 6101 if (FieldName) 6102 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6103 << FieldName << (unsigned)Value.getZExtValue() 6104 << (unsigned)TypeSize; 6105 6106 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6107 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6108 } 6109 6110 if (FieldName) 6111 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6112 << FieldName << (unsigned)Value.getZExtValue() 6113 << (unsigned)TypeSize; 6114 else 6115 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6116 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6117 } 6118 } 6119 6120 return false; 6121} 6122 6123/// ActOnField - Each field of a struct/union/class is passed into this in order 6124/// to create a FieldDecl object for it. 6125Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6126 SourceLocation DeclStart, 6127 Declarator &D, ExprTy *BitfieldWidth) { 6128 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6129 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6130 AS_public); 6131 return Res; 6132} 6133 6134/// HandleField - Analyze a field of a C struct or a C++ data member. 6135/// 6136FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6137 SourceLocation DeclStart, 6138 Declarator &D, Expr *BitWidth, 6139 AccessSpecifier AS) { 6140 IdentifierInfo *II = D.getIdentifier(); 6141 SourceLocation Loc = DeclStart; 6142 if (II) Loc = D.getIdentifierLoc(); 6143 6144 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6145 QualType T = TInfo->getType(); 6146 if (getLangOptions().CPlusPlus) 6147 CheckExtraCXXDefaultArguments(D); 6148 6149 DiagnoseFunctionSpecifiers(D); 6150 6151 if (D.getDeclSpec().isThreadSpecified()) 6152 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6153 6154 // Check to see if this name was declared as a member previously 6155 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6156 LookupName(Previous, S); 6157 assert((Previous.empty() || Previous.isOverloadedResult() || 6158 Previous.isSingleResult()) 6159 && "Lookup of member name should be either overloaded, single or null"); 6160 6161 // If the name is overloaded then get any declaration else get the single result 6162 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6163 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6164 6165 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6166 // Maybe we will complain about the shadowed template parameter. 6167 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6168 // Just pretend that we didn't see the previous declaration. 6169 PrevDecl = 0; 6170 } 6171 6172 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6173 PrevDecl = 0; 6174 6175 bool Mutable 6176 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6177 SourceLocation TSSL = D.getSourceRange().getBegin(); 6178 FieldDecl *NewFD 6179 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6180 AS, PrevDecl, &D); 6181 6182 if (NewFD->isInvalidDecl()) 6183 Record->setInvalidDecl(); 6184 6185 if (NewFD->isInvalidDecl() && PrevDecl) { 6186 // Don't introduce NewFD into scope; there's already something 6187 // with the same name in the same scope. 6188 } else if (II) { 6189 PushOnScopeChains(NewFD, S); 6190 } else 6191 Record->addDecl(NewFD); 6192 6193 return NewFD; 6194} 6195 6196/// \brief Build a new FieldDecl and check its well-formedness. 6197/// 6198/// This routine builds a new FieldDecl given the fields name, type, 6199/// record, etc. \p PrevDecl should refer to any previous declaration 6200/// with the same name and in the same scope as the field to be 6201/// created. 6202/// 6203/// \returns a new FieldDecl. 6204/// 6205/// \todo The Declarator argument is a hack. It will be removed once 6206FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6207 TypeSourceInfo *TInfo, 6208 RecordDecl *Record, SourceLocation Loc, 6209 bool Mutable, Expr *BitWidth, 6210 SourceLocation TSSL, 6211 AccessSpecifier AS, NamedDecl *PrevDecl, 6212 Declarator *D) { 6213 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6214 bool InvalidDecl = false; 6215 if (D) InvalidDecl = D->isInvalidType(); 6216 6217 // If we receive a broken type, recover by assuming 'int' and 6218 // marking this declaration as invalid. 6219 if (T.isNull()) { 6220 InvalidDecl = true; 6221 T = Context.IntTy; 6222 } 6223 6224 QualType EltTy = Context.getBaseElementType(T); 6225 if (!EltTy->isDependentType() && 6226 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6227 // Fields of incomplete type force their record to be invalid. 6228 Record->setInvalidDecl(); 6229 InvalidDecl = true; 6230 } 6231 6232 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6233 // than a variably modified type. 6234 if (!InvalidDecl && T->isVariablyModifiedType()) { 6235 bool SizeIsNegative; 6236 llvm::APSInt Oversized; 6237 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6238 SizeIsNegative, 6239 Oversized); 6240 if (!FixedTy.isNull()) { 6241 Diag(Loc, diag::warn_illegal_constant_array_size); 6242 T = FixedTy; 6243 } else { 6244 if (SizeIsNegative) 6245 Diag(Loc, diag::err_typecheck_negative_array_size); 6246 else if (Oversized.getBoolValue()) 6247 Diag(Loc, diag::err_array_too_large) 6248 << Oversized.toString(10); 6249 else 6250 Diag(Loc, diag::err_typecheck_field_variable_size); 6251 InvalidDecl = true; 6252 } 6253 } 6254 6255 // Fields can not have abstract class types 6256 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6257 diag::err_abstract_type_in_decl, 6258 AbstractFieldType)) 6259 InvalidDecl = true; 6260 6261 bool ZeroWidth = false; 6262 // If this is declared as a bit-field, check the bit-field. 6263 if (!InvalidDecl && BitWidth && 6264 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6265 InvalidDecl = true; 6266 BitWidth = 0; 6267 ZeroWidth = false; 6268 } 6269 6270 // Check that 'mutable' is consistent with the type of the declaration. 6271 if (!InvalidDecl && Mutable) { 6272 unsigned DiagID = 0; 6273 if (T->isReferenceType()) 6274 DiagID = diag::err_mutable_reference; 6275 else if (T.isConstQualified()) 6276 DiagID = diag::err_mutable_const; 6277 6278 if (DiagID) { 6279 SourceLocation ErrLoc = Loc; 6280 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6281 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6282 Diag(ErrLoc, DiagID); 6283 Mutable = false; 6284 InvalidDecl = true; 6285 } 6286 } 6287 6288 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6289 BitWidth, Mutable); 6290 if (InvalidDecl) 6291 NewFD->setInvalidDecl(); 6292 6293 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6294 Diag(Loc, diag::err_duplicate_member) << II; 6295 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6296 NewFD->setInvalidDecl(); 6297 } 6298 6299 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6300 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6301 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6302 if (RDecl->getDefinition()) { 6303 // C++ 9.5p1: An object of a class with a non-trivial 6304 // constructor, a non-trivial copy constructor, a non-trivial 6305 // destructor, or a non-trivial copy assignment operator 6306 // cannot be a member of a union, nor can an array of such 6307 // objects. 6308 // TODO: C++0x alters this restriction significantly. 6309 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6310 NewFD->setInvalidDecl(); 6311 } 6312 } 6313 } 6314 6315 // FIXME: We need to pass in the attributes given an AST 6316 // representation, not a parser representation. 6317 if (D) 6318 // FIXME: What to pass instead of TUScope? 6319 ProcessDeclAttributes(TUScope, NewFD, *D); 6320 6321 if (T.isObjCGCWeak()) 6322 Diag(Loc, diag::warn_attribute_weak_on_field); 6323 6324 NewFD->setAccess(AS); 6325 return NewFD; 6326} 6327 6328bool Sema::CheckNontrivialField(FieldDecl *FD) { 6329 assert(FD); 6330 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6331 6332 if (FD->isInvalidDecl()) 6333 return true; 6334 6335 QualType EltTy = Context.getBaseElementType(FD->getType()); 6336 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6337 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6338 if (RDecl->getDefinition()) { 6339 // We check for copy constructors before constructors 6340 // because otherwise we'll never get complaints about 6341 // copy constructors. 6342 6343 CXXSpecialMember member = CXXInvalid; 6344 if (!RDecl->hasTrivialCopyConstructor()) 6345 member = CXXCopyConstructor; 6346 else if (!RDecl->hasTrivialConstructor()) 6347 member = CXXConstructor; 6348 else if (!RDecl->hasTrivialCopyAssignment()) 6349 member = CXXCopyAssignment; 6350 else if (!RDecl->hasTrivialDestructor()) 6351 member = CXXDestructor; 6352 6353 if (member != CXXInvalid) { 6354 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6355 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6356 DiagnoseNontrivial(RT, member); 6357 return true; 6358 } 6359 } 6360 } 6361 6362 return false; 6363} 6364 6365/// DiagnoseNontrivial - Given that a class has a non-trivial 6366/// special member, figure out why. 6367void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6368 QualType QT(T, 0U); 6369 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6370 6371 // Check whether the member was user-declared. 6372 switch (member) { 6373 case CXXInvalid: 6374 break; 6375 6376 case CXXConstructor: 6377 if (RD->hasUserDeclaredConstructor()) { 6378 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6379 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6380 const FunctionDecl *body = 0; 6381 ci->hasBody(body); 6382 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6383 SourceLocation CtorLoc = ci->getLocation(); 6384 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6385 return; 6386 } 6387 } 6388 6389 assert(0 && "found no user-declared constructors"); 6390 return; 6391 } 6392 break; 6393 6394 case CXXCopyConstructor: 6395 if (RD->hasUserDeclaredCopyConstructor()) { 6396 SourceLocation CtorLoc = 6397 RD->getCopyConstructor(Context, 0)->getLocation(); 6398 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6399 return; 6400 } 6401 break; 6402 6403 case CXXCopyAssignment: 6404 if (RD->hasUserDeclaredCopyAssignment()) { 6405 // FIXME: this should use the location of the copy 6406 // assignment, not the type. 6407 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6408 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6409 return; 6410 } 6411 break; 6412 6413 case CXXDestructor: 6414 if (RD->hasUserDeclaredDestructor()) { 6415 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6416 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6417 return; 6418 } 6419 break; 6420 } 6421 6422 typedef CXXRecordDecl::base_class_iterator base_iter; 6423 6424 // Virtual bases and members inhibit trivial copying/construction, 6425 // but not trivial destruction. 6426 if (member != CXXDestructor) { 6427 // Check for virtual bases. vbases includes indirect virtual bases, 6428 // so we just iterate through the direct bases. 6429 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6430 if (bi->isVirtual()) { 6431 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6432 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6433 return; 6434 } 6435 6436 // Check for virtual methods. 6437 typedef CXXRecordDecl::method_iterator meth_iter; 6438 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6439 ++mi) { 6440 if (mi->isVirtual()) { 6441 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6442 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6443 return; 6444 } 6445 } 6446 } 6447 6448 bool (CXXRecordDecl::*hasTrivial)() const; 6449 switch (member) { 6450 case CXXConstructor: 6451 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6452 case CXXCopyConstructor: 6453 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6454 case CXXCopyAssignment: 6455 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6456 case CXXDestructor: 6457 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6458 default: 6459 assert(0 && "unexpected special member"); return; 6460 } 6461 6462 // Check for nontrivial bases (and recurse). 6463 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6464 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6465 assert(BaseRT && "Don't know how to handle dependent bases"); 6466 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6467 if (!(BaseRecTy->*hasTrivial)()) { 6468 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6469 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6470 DiagnoseNontrivial(BaseRT, member); 6471 return; 6472 } 6473 } 6474 6475 // Check for nontrivial members (and recurse). 6476 typedef RecordDecl::field_iterator field_iter; 6477 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6478 ++fi) { 6479 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6480 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6481 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6482 6483 if (!(EltRD->*hasTrivial)()) { 6484 SourceLocation FLoc = (*fi)->getLocation(); 6485 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6486 DiagnoseNontrivial(EltRT, member); 6487 return; 6488 } 6489 } 6490 } 6491 6492 assert(0 && "found no explanation for non-trivial member"); 6493} 6494 6495/// TranslateIvarVisibility - Translate visibility from a token ID to an 6496/// AST enum value. 6497static ObjCIvarDecl::AccessControl 6498TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6499 switch (ivarVisibility) { 6500 default: assert(0 && "Unknown visitibility kind"); 6501 case tok::objc_private: return ObjCIvarDecl::Private; 6502 case tok::objc_public: return ObjCIvarDecl::Public; 6503 case tok::objc_protected: return ObjCIvarDecl::Protected; 6504 case tok::objc_package: return ObjCIvarDecl::Package; 6505 } 6506} 6507 6508/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6509/// in order to create an IvarDecl object for it. 6510Decl *Sema::ActOnIvar(Scope *S, 6511 SourceLocation DeclStart, 6512 Decl *IntfDecl, 6513 Declarator &D, ExprTy *BitfieldWidth, 6514 tok::ObjCKeywordKind Visibility) { 6515 6516 IdentifierInfo *II = D.getIdentifier(); 6517 Expr *BitWidth = (Expr*)BitfieldWidth; 6518 SourceLocation Loc = DeclStart; 6519 if (II) Loc = D.getIdentifierLoc(); 6520 6521 // FIXME: Unnamed fields can be handled in various different ways, for 6522 // example, unnamed unions inject all members into the struct namespace! 6523 6524 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6525 QualType T = TInfo->getType(); 6526 6527 if (BitWidth) { 6528 // 6.7.2.1p3, 6.7.2.1p4 6529 if (VerifyBitField(Loc, II, T, BitWidth)) { 6530 D.setInvalidType(); 6531 BitWidth = 0; 6532 } 6533 } else { 6534 // Not a bitfield. 6535 6536 // validate II. 6537 6538 } 6539 if (T->isReferenceType()) { 6540 Diag(Loc, diag::err_ivar_reference_type); 6541 D.setInvalidType(); 6542 } 6543 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6544 // than a variably modified type. 6545 else if (T->isVariablyModifiedType()) { 6546 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6547 D.setInvalidType(); 6548 } 6549 6550 // Get the visibility (access control) for this ivar. 6551 ObjCIvarDecl::AccessControl ac = 6552 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6553 : ObjCIvarDecl::None; 6554 // Must set ivar's DeclContext to its enclosing interface. 6555 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6556 ObjCContainerDecl *EnclosingContext; 6557 if (ObjCImplementationDecl *IMPDecl = 6558 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6559 if (!LangOpts.ObjCNonFragileABI2) { 6560 // Case of ivar declared in an implementation. Context is that of its class. 6561 EnclosingContext = IMPDecl->getClassInterface(); 6562 assert(EnclosingContext && "Implementation has no class interface!"); 6563 } 6564 else 6565 EnclosingContext = EnclosingDecl; 6566 } else { 6567 if (ObjCCategoryDecl *CDecl = 6568 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6569 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6570 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6571 return 0; 6572 } 6573 } 6574 EnclosingContext = EnclosingDecl; 6575 } 6576 6577 // Construct the decl. 6578 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6579 EnclosingContext, Loc, II, T, 6580 TInfo, ac, (Expr *)BitfieldWidth); 6581 6582 if (II) { 6583 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6584 ForRedeclaration); 6585 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6586 && !isa<TagDecl>(PrevDecl)) { 6587 Diag(Loc, diag::err_duplicate_member) << II; 6588 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6589 NewID->setInvalidDecl(); 6590 } 6591 } 6592 6593 // Process attributes attached to the ivar. 6594 ProcessDeclAttributes(S, NewID, D); 6595 6596 if (D.isInvalidType()) 6597 NewID->setInvalidDecl(); 6598 6599 if (II) { 6600 // FIXME: When interfaces are DeclContexts, we'll need to add 6601 // these to the interface. 6602 S->AddDecl(NewID); 6603 IdResolver.AddDecl(NewID); 6604 } 6605 6606 return NewID; 6607} 6608 6609/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6610/// class and class extensions. For every class @interface and class 6611/// extension @interface, if the last ivar is a bitfield of any type, 6612/// then add an implicit `char :0` ivar to the end of that interface. 6613void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6614 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6615 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6616 return; 6617 6618 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6619 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6620 6621 if (!Ivar->isBitField()) 6622 return; 6623 uint64_t BitFieldSize = 6624 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6625 if (BitFieldSize == 0) 6626 return; 6627 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6628 if (!ID) { 6629 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6630 if (!CD->IsClassExtension()) 6631 return; 6632 } 6633 // No need to add this to end of @implementation. 6634 else 6635 return; 6636 } 6637 // All conditions are met. Add a new bitfield to the tail end of ivars. 6638 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6639 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6640 6641 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6642 DeclLoc, 0, 6643 Context.CharTy, 6644 Context.CreateTypeSourceInfo(Context.CharTy), 6645 ObjCIvarDecl::Private, BW, 6646 true); 6647 AllIvarDecls.push_back(Ivar); 6648} 6649 6650void Sema::ActOnFields(Scope* S, 6651 SourceLocation RecLoc, Decl *EnclosingDecl, 6652 Decl **Fields, unsigned NumFields, 6653 SourceLocation LBrac, SourceLocation RBrac, 6654 AttributeList *Attr) { 6655 assert(EnclosingDecl && "missing record or interface decl"); 6656 6657 // If the decl this is being inserted into is invalid, then it may be a 6658 // redeclaration or some other bogus case. Don't try to add fields to it. 6659 if (EnclosingDecl->isInvalidDecl()) { 6660 // FIXME: Deallocate fields? 6661 return; 6662 } 6663 6664 6665 // Verify that all the fields are okay. 6666 unsigned NumNamedMembers = 0; 6667 llvm::SmallVector<FieldDecl*, 32> RecFields; 6668 6669 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6670 for (unsigned i = 0; i != NumFields; ++i) { 6671 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6672 6673 // Get the type for the field. 6674 Type *FDTy = FD->getType().getTypePtr(); 6675 6676 if (!FD->isAnonymousStructOrUnion()) { 6677 // Remember all fields written by the user. 6678 RecFields.push_back(FD); 6679 } 6680 6681 // If the field is already invalid for some reason, don't emit more 6682 // diagnostics about it. 6683 if (FD->isInvalidDecl()) { 6684 EnclosingDecl->setInvalidDecl(); 6685 continue; 6686 } 6687 6688 // C99 6.7.2.1p2: 6689 // A structure or union shall not contain a member with 6690 // incomplete or function type (hence, a structure shall not 6691 // contain an instance of itself, but may contain a pointer to 6692 // an instance of itself), except that the last member of a 6693 // structure with more than one named member may have incomplete 6694 // array type; such a structure (and any union containing, 6695 // possibly recursively, a member that is such a structure) 6696 // shall not be a member of a structure or an element of an 6697 // array. 6698 if (FDTy->isFunctionType()) { 6699 // Field declared as a function. 6700 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6701 << FD->getDeclName(); 6702 FD->setInvalidDecl(); 6703 EnclosingDecl->setInvalidDecl(); 6704 continue; 6705 } else if (FDTy->isIncompleteArrayType() && Record && 6706 ((i == NumFields - 1 && !Record->isUnion()) || 6707 (getLangOptions().Microsoft && 6708 (i == NumFields - 1 || Record->isUnion())))) { 6709 // Flexible array member. 6710 // Microsoft is more permissive regarding flexible array. 6711 // It will accept flexible array in union and also 6712 // as the sole element of a struct/class. 6713 if (getLangOptions().Microsoft) { 6714 if (Record->isUnion()) 6715 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6716 << FD->getDeclName(); 6717 else if (NumFields == 1) 6718 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6719 << FD->getDeclName() << Record->getTagKind(); 6720 } else if (NumNamedMembers < 1) { 6721 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6722 << FD->getDeclName(); 6723 FD->setInvalidDecl(); 6724 EnclosingDecl->setInvalidDecl(); 6725 continue; 6726 } 6727 if (!FD->getType()->isDependentType() && 6728 !Context.getBaseElementType(FD->getType())->isPODType()) { 6729 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6730 << FD->getDeclName() << FD->getType(); 6731 FD->setInvalidDecl(); 6732 EnclosingDecl->setInvalidDecl(); 6733 continue; 6734 } 6735 // Okay, we have a legal flexible array member at the end of the struct. 6736 if (Record) 6737 Record->setHasFlexibleArrayMember(true); 6738 } else if (!FDTy->isDependentType() && 6739 RequireCompleteType(FD->getLocation(), FD->getType(), 6740 diag::err_field_incomplete)) { 6741 // Incomplete type 6742 FD->setInvalidDecl(); 6743 EnclosingDecl->setInvalidDecl(); 6744 continue; 6745 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6746 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6747 // If this is a member of a union, then entire union becomes "flexible". 6748 if (Record && Record->isUnion()) { 6749 Record->setHasFlexibleArrayMember(true); 6750 } else { 6751 // If this is a struct/class and this is not the last element, reject 6752 // it. Note that GCC supports variable sized arrays in the middle of 6753 // structures. 6754 if (i != NumFields-1) 6755 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6756 << FD->getDeclName() << FD->getType(); 6757 else { 6758 // We support flexible arrays at the end of structs in 6759 // other structs as an extension. 6760 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6761 << FD->getDeclName(); 6762 if (Record) 6763 Record->setHasFlexibleArrayMember(true); 6764 } 6765 } 6766 } 6767 if (Record && FDTTy->getDecl()->hasObjectMember()) 6768 Record->setHasObjectMember(true); 6769 } else if (FDTy->isObjCObjectType()) { 6770 /// A field cannot be an Objective-c object 6771 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6772 FD->setInvalidDecl(); 6773 EnclosingDecl->setInvalidDecl(); 6774 continue; 6775 } else if (getLangOptions().ObjC1 && 6776 getLangOptions().getGCMode() != LangOptions::NonGC && 6777 Record && 6778 (FD->getType()->isObjCObjectPointerType() || 6779 FD->getType().isObjCGCStrong())) 6780 Record->setHasObjectMember(true); 6781 else if (Context.getAsArrayType(FD->getType())) { 6782 QualType BaseType = Context.getBaseElementType(FD->getType()); 6783 if (Record && BaseType->isRecordType() && 6784 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6785 Record->setHasObjectMember(true); 6786 } 6787 // Keep track of the number of named members. 6788 if (FD->getIdentifier()) 6789 ++NumNamedMembers; 6790 } 6791 6792 // Okay, we successfully defined 'Record'. 6793 if (Record) { 6794 bool Completed = false; 6795 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 6796 if (!CXXRecord->isInvalidDecl()) { 6797 // Set access bits correctly on the directly-declared conversions. 6798 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 6799 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 6800 I != E; ++I) 6801 Convs->setAccess(I, (*I)->getAccess()); 6802 6803 if (!CXXRecord->isDependentType()) { 6804 // Add any implicitly-declared members to this class. 6805 AddImplicitlyDeclaredMembersToClass(CXXRecord); 6806 6807 // If we have virtual base classes, we may end up finding multiple 6808 // final overriders for a given virtual function. Check for this 6809 // problem now. 6810 if (CXXRecord->getNumVBases()) { 6811 CXXFinalOverriderMap FinalOverriders; 6812 CXXRecord->getFinalOverriders(FinalOverriders); 6813 6814 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 6815 MEnd = FinalOverriders.end(); 6816 M != MEnd; ++M) { 6817 for (OverridingMethods::iterator SO = M->second.begin(), 6818 SOEnd = M->second.end(); 6819 SO != SOEnd; ++SO) { 6820 assert(SO->second.size() > 0 && 6821 "Virtual function without overridding functions?"); 6822 if (SO->second.size() == 1) 6823 continue; 6824 6825 // C++ [class.virtual]p2: 6826 // In a derived class, if a virtual member function of a base 6827 // class subobject has more than one final overrider the 6828 // program is ill-formed. 6829 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 6830 << (NamedDecl *)M->first << Record; 6831 Diag(M->first->getLocation(), 6832 diag::note_overridden_virtual_function); 6833 for (OverridingMethods::overriding_iterator 6834 OM = SO->second.begin(), 6835 OMEnd = SO->second.end(); 6836 OM != OMEnd; ++OM) 6837 Diag(OM->Method->getLocation(), diag::note_final_overrider) 6838 << (NamedDecl *)M->first << OM->Method->getParent(); 6839 6840 Record->setInvalidDecl(); 6841 } 6842 } 6843 CXXRecord->completeDefinition(&FinalOverriders); 6844 Completed = true; 6845 } 6846 } 6847 } 6848 } 6849 6850 if (!Completed) 6851 Record->completeDefinition(); 6852 } else { 6853 ObjCIvarDecl **ClsFields = 6854 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6855 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6856 ID->setLocEnd(RBrac); 6857 // Add ivar's to class's DeclContext. 6858 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6859 ClsFields[i]->setLexicalDeclContext(ID); 6860 ID->addDecl(ClsFields[i]); 6861 } 6862 // Must enforce the rule that ivars in the base classes may not be 6863 // duplicates. 6864 if (ID->getSuperClass()) 6865 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6866 } else if (ObjCImplementationDecl *IMPDecl = 6867 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6868 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6869 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6870 // Ivar declared in @implementation never belongs to the implementation. 6871 // Only it is in implementation's lexical context. 6872 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6873 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6874 } else if (ObjCCategoryDecl *CDecl = 6875 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6876 // case of ivars in class extension; all other cases have been 6877 // reported as errors elsewhere. 6878 // FIXME. Class extension does not have a LocEnd field. 6879 // CDecl->setLocEnd(RBrac); 6880 // Add ivar's to class extension's DeclContext. 6881 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6882 ClsFields[i]->setLexicalDeclContext(CDecl); 6883 CDecl->addDecl(ClsFields[i]); 6884 } 6885 } 6886 } 6887 6888 if (Attr) 6889 ProcessDeclAttributeList(S, Record, Attr); 6890 6891 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6892 // set the visibility of this record. 6893 if (Record && !Record->getDeclContext()->isRecord()) 6894 AddPushedVisibilityAttribute(Record); 6895} 6896 6897/// \brief Determine whether the given integral value is representable within 6898/// the given type T. 6899static bool isRepresentableIntegerValue(ASTContext &Context, 6900 llvm::APSInt &Value, 6901 QualType T) { 6902 assert(T->isIntegralType(Context) && "Integral type required!"); 6903 unsigned BitWidth = Context.getIntWidth(T); 6904 6905 if (Value.isUnsigned() || Value.isNonNegative()) { 6906 if (T->isSignedIntegerType()) 6907 --BitWidth; 6908 return Value.getActiveBits() <= BitWidth; 6909 } 6910 return Value.getMinSignedBits() <= BitWidth; 6911} 6912 6913// \brief Given an integral type, return the next larger integral type 6914// (or a NULL type of no such type exists). 6915static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6916 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6917 // enum checking below. 6918 assert(T->isIntegralType(Context) && "Integral type required!"); 6919 const unsigned NumTypes = 4; 6920 QualType SignedIntegralTypes[NumTypes] = { 6921 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6922 }; 6923 QualType UnsignedIntegralTypes[NumTypes] = { 6924 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6925 Context.UnsignedLongLongTy 6926 }; 6927 6928 unsigned BitWidth = Context.getTypeSize(T); 6929 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6930 : UnsignedIntegralTypes; 6931 for (unsigned I = 0; I != NumTypes; ++I) 6932 if (Context.getTypeSize(Types[I]) > BitWidth) 6933 return Types[I]; 6934 6935 return QualType(); 6936} 6937 6938EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6939 EnumConstantDecl *LastEnumConst, 6940 SourceLocation IdLoc, 6941 IdentifierInfo *Id, 6942 Expr *Val) { 6943 unsigned IntWidth = Context.Target.getIntWidth(); 6944 llvm::APSInt EnumVal(IntWidth); 6945 QualType EltTy; 6946 if (Val) { 6947 if (Enum->isDependentType() || Val->isTypeDependent()) 6948 EltTy = Context.DependentTy; 6949 else { 6950 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6951 SourceLocation ExpLoc; 6952 if (!Val->isValueDependent() && 6953 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6954 Val = 0; 6955 } else { 6956 if (!getLangOptions().CPlusPlus) { 6957 // C99 6.7.2.2p2: 6958 // The expression that defines the value of an enumeration constant 6959 // shall be an integer constant expression that has a value 6960 // representable as an int. 6961 6962 // Complain if the value is not representable in an int. 6963 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6964 Diag(IdLoc, diag::ext_enum_value_not_int) 6965 << EnumVal.toString(10) << Val->getSourceRange() 6966 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6967 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6968 // Force the type of the expression to 'int'. 6969 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 6970 } 6971 } 6972 6973 if (Enum->isFixed()) { 6974 EltTy = Enum->getIntegerType(); 6975 6976 // C++0x [dcl.enum]p5: 6977 // ... if the initializing value of an enumerator cannot be 6978 // represented by the underlying type, the program is ill-formed. 6979 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) 6980 Diag(IdLoc, diag::err_enumerator_too_large) 6981 << EltTy; 6982 else 6983 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 6984 } 6985 else { 6986 // C++0x [dcl.enum]p5: 6987 // If the underlying type is not fixed, the type of each enumerator 6988 // is the type of its initializing value: 6989 // - If an initializer is specified for an enumerator, the 6990 // initializing value has the same type as the expression. 6991 EltTy = Val->getType(); 6992 } 6993 } 6994 } 6995 } 6996 6997 if (!Val) { 6998 if (Enum->isDependentType()) 6999 EltTy = Context.DependentTy; 7000 else if (!LastEnumConst) { 7001 // C++0x [dcl.enum]p5: 7002 // If the underlying type is not fixed, the type of each enumerator 7003 // is the type of its initializing value: 7004 // - If no initializer is specified for the first enumerator, the 7005 // initializing value has an unspecified integral type. 7006 // 7007 // GCC uses 'int' for its unspecified integral type, as does 7008 // C99 6.7.2.2p3. 7009 if (Enum->isFixed()) { 7010 EltTy = Enum->getIntegerType(); 7011 } 7012 else { 7013 EltTy = Context.IntTy; 7014 } 7015 } else { 7016 // Assign the last value + 1. 7017 EnumVal = LastEnumConst->getInitVal(); 7018 ++EnumVal; 7019 EltTy = LastEnumConst->getType(); 7020 7021 // Check for overflow on increment. 7022 if (EnumVal < LastEnumConst->getInitVal()) { 7023 // C++0x [dcl.enum]p5: 7024 // If the underlying type is not fixed, the type of each enumerator 7025 // is the type of its initializing value: 7026 // 7027 // - Otherwise the type of the initializing value is the same as 7028 // the type of the initializing value of the preceding enumerator 7029 // unless the incremented value is not representable in that type, 7030 // in which case the type is an unspecified integral type 7031 // sufficient to contain the incremented value. If no such type 7032 // exists, the program is ill-formed. 7033 QualType T = getNextLargerIntegralType(Context, EltTy); 7034 if (T.isNull() || Enum->isFixed()) { 7035 // There is no integral type larger enough to represent this 7036 // value. Complain, then allow the value to wrap around. 7037 EnumVal = LastEnumConst->getInitVal(); 7038 EnumVal.zext(EnumVal.getBitWidth() * 2); 7039 ++EnumVal; 7040 if (Enum->isFixed()) 7041 // When the underlying type is fixed, this is ill-formed. 7042 Diag(IdLoc, diag::err_enumerator_wrapped) 7043 << EnumVal.toString(10) 7044 << EltTy; 7045 else 7046 Diag(IdLoc, diag::warn_enumerator_too_large) 7047 << EnumVal.toString(10); 7048 } else { 7049 EltTy = T; 7050 } 7051 7052 // Retrieve the last enumerator's value, extent that type to the 7053 // type that is supposed to be large enough to represent the incremented 7054 // value, then increment. 7055 EnumVal = LastEnumConst->getInitVal(); 7056 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7057 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7058 ++EnumVal; 7059 7060 // If we're not in C++, diagnose the overflow of enumerator values, 7061 // which in C99 means that the enumerator value is not representable in 7062 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7063 // permits enumerator values that are representable in some larger 7064 // integral type. 7065 if (!getLangOptions().CPlusPlus && !T.isNull()) 7066 Diag(IdLoc, diag::warn_enum_value_overflow); 7067 } else if (!getLangOptions().CPlusPlus && 7068 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7069 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7070 Diag(IdLoc, diag::ext_enum_value_not_int) 7071 << EnumVal.toString(10) << 1; 7072 } 7073 } 7074 } 7075 7076 if (!EltTy->isDependentType()) { 7077 // Make the enumerator value match the signedness and size of the 7078 // enumerator's type. 7079 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7080 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7081 } 7082 7083 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7084 Val, EnumVal); 7085} 7086 7087 7088Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 7089 Decl *lastEnumConst, 7090 SourceLocation IdLoc, 7091 IdentifierInfo *Id, 7092 SourceLocation EqualLoc, ExprTy *val) { 7093 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7094 EnumConstantDecl *LastEnumConst = 7095 cast_or_null<EnumConstantDecl>(lastEnumConst); 7096 Expr *Val = static_cast<Expr*>(val); 7097 7098 // The scope passed in may not be a decl scope. Zip up the scope tree until 7099 // we find one that is. 7100 S = getNonFieldDeclScope(S); 7101 7102 // Verify that there isn't already something declared with this name in this 7103 // scope. 7104 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7105 ForRedeclaration); 7106 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7107 // Maybe we will complain about the shadowed template parameter. 7108 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7109 // Just pretend that we didn't see the previous declaration. 7110 PrevDecl = 0; 7111 } 7112 7113 if (PrevDecl) { 7114 // When in C++, we may get a TagDecl with the same name; in this case the 7115 // enum constant will 'hide' the tag. 7116 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7117 "Received TagDecl when not in C++!"); 7118 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7119 if (isa<EnumConstantDecl>(PrevDecl)) 7120 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7121 else 7122 Diag(IdLoc, diag::err_redefinition) << Id; 7123 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7124 return 0; 7125 } 7126 } 7127 7128 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 7129 IdLoc, Id, Val); 7130 7131 // Register this decl in the current scope stack. 7132 if (New) { 7133 New->setAccess(TheEnumDecl->getAccess()); 7134 PushOnScopeChains(New, S); 7135 } 7136 7137 return New; 7138} 7139 7140void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7141 SourceLocation RBraceLoc, Decl *EnumDeclX, 7142 Decl **Elements, unsigned NumElements, 7143 Scope *S, AttributeList *Attr) { 7144 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7145 QualType EnumType = Context.getTypeDeclType(Enum); 7146 7147 if (Attr) 7148 ProcessDeclAttributeList(S, Enum, Attr); 7149 7150 if (Enum->isDependentType()) { 7151 for (unsigned i = 0; i != NumElements; ++i) { 7152 EnumConstantDecl *ECD = 7153 cast_or_null<EnumConstantDecl>(Elements[i]); 7154 if (!ECD) continue; 7155 7156 ECD->setType(EnumType); 7157 } 7158 7159 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7160 return; 7161 } 7162 7163 // TODO: If the result value doesn't fit in an int, it must be a long or long 7164 // long value. ISO C does not support this, but GCC does as an extension, 7165 // emit a warning. 7166 unsigned IntWidth = Context.Target.getIntWidth(); 7167 unsigned CharWidth = Context.Target.getCharWidth(); 7168 unsigned ShortWidth = Context.Target.getShortWidth(); 7169 7170 // Verify that all the values are okay, compute the size of the values, and 7171 // reverse the list. 7172 unsigned NumNegativeBits = 0; 7173 unsigned NumPositiveBits = 0; 7174 7175 // Keep track of whether all elements have type int. 7176 bool AllElementsInt = true; 7177 7178 for (unsigned i = 0; i != NumElements; ++i) { 7179 EnumConstantDecl *ECD = 7180 cast_or_null<EnumConstantDecl>(Elements[i]); 7181 if (!ECD) continue; // Already issued a diagnostic. 7182 7183 const llvm::APSInt &InitVal = ECD->getInitVal(); 7184 7185 // Keep track of the size of positive and negative values. 7186 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7187 NumPositiveBits = std::max(NumPositiveBits, 7188 (unsigned)InitVal.getActiveBits()); 7189 else 7190 NumNegativeBits = std::max(NumNegativeBits, 7191 (unsigned)InitVal.getMinSignedBits()); 7192 7193 // Keep track of whether every enum element has type int (very commmon). 7194 if (AllElementsInt) 7195 AllElementsInt = ECD->getType() == Context.IntTy; 7196 } 7197 7198 // Figure out the type that should be used for this enum. 7199 // FIXME: Support -fshort-enums. 7200 QualType BestType; 7201 unsigned BestWidth; 7202 7203 // C++0x N3000 [conv.prom]p3: 7204 // An rvalue of an unscoped enumeration type whose underlying 7205 // type is not fixed can be converted to an rvalue of the first 7206 // of the following types that can represent all the values of 7207 // the enumeration: int, unsigned int, long int, unsigned long 7208 // int, long long int, or unsigned long long int. 7209 // C99 6.4.4.3p2: 7210 // An identifier declared as an enumeration constant has type int. 7211 // The C99 rule is modified by a gcc extension 7212 QualType BestPromotionType; 7213 7214 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7215 // -fshort-enums is the equivalent to specifying the packed attribute on all 7216 // enum definitions. 7217 if (LangOpts.ShortEnums) 7218 Packed = true; 7219 7220 if (Enum->isFixed()) { 7221 BestType = BestPromotionType = Enum->getIntegerType(); 7222 // We don't need to set BestWidth, because BestType is going to be the type 7223 // of the enumerators, but we do anyway because otherwise some compilers 7224 // warn that it might be used uninitialized. 7225 BestWidth = CharWidth; 7226 } 7227 else if (NumNegativeBits) { 7228 // If there is a negative value, figure out the smallest integer type (of 7229 // int/long/longlong) that fits. 7230 // If it's packed, check also if it fits a char or a short. 7231 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7232 BestType = Context.SignedCharTy; 7233 BestWidth = CharWidth; 7234 } else if (Packed && NumNegativeBits <= ShortWidth && 7235 NumPositiveBits < ShortWidth) { 7236 BestType = Context.ShortTy; 7237 BestWidth = ShortWidth; 7238 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7239 BestType = Context.IntTy; 7240 BestWidth = IntWidth; 7241 } else { 7242 BestWidth = Context.Target.getLongWidth(); 7243 7244 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7245 BestType = Context.LongTy; 7246 } else { 7247 BestWidth = Context.Target.getLongLongWidth(); 7248 7249 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7250 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7251 BestType = Context.LongLongTy; 7252 } 7253 } 7254 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7255 } else { 7256 // If there is no negative value, figure out the smallest type that fits 7257 // all of the enumerator values. 7258 // If it's packed, check also if it fits a char or a short. 7259 if (Packed && NumPositiveBits <= CharWidth) { 7260 BestType = Context.UnsignedCharTy; 7261 BestPromotionType = Context.IntTy; 7262 BestWidth = CharWidth; 7263 } else if (Packed && NumPositiveBits <= ShortWidth) { 7264 BestType = Context.UnsignedShortTy; 7265 BestPromotionType = Context.IntTy; 7266 BestWidth = ShortWidth; 7267 } else if (NumPositiveBits <= IntWidth) { 7268 BestType = Context.UnsignedIntTy; 7269 BestWidth = IntWidth; 7270 BestPromotionType 7271 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7272 ? Context.UnsignedIntTy : Context.IntTy; 7273 } else if (NumPositiveBits <= 7274 (BestWidth = Context.Target.getLongWidth())) { 7275 BestType = Context.UnsignedLongTy; 7276 BestPromotionType 7277 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7278 ? Context.UnsignedLongTy : Context.LongTy; 7279 } else { 7280 BestWidth = Context.Target.getLongLongWidth(); 7281 assert(NumPositiveBits <= BestWidth && 7282 "How could an initializer get larger than ULL?"); 7283 BestType = Context.UnsignedLongLongTy; 7284 BestPromotionType 7285 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7286 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7287 } 7288 } 7289 7290 // Loop over all of the enumerator constants, changing their types to match 7291 // the type of the enum if needed. 7292 for (unsigned i = 0; i != NumElements; ++i) { 7293 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7294 if (!ECD) continue; // Already issued a diagnostic. 7295 7296 // Standard C says the enumerators have int type, but we allow, as an 7297 // extension, the enumerators to be larger than int size. If each 7298 // enumerator value fits in an int, type it as an int, otherwise type it the 7299 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7300 // that X has type 'int', not 'unsigned'. 7301 7302 // Determine whether the value fits into an int. 7303 llvm::APSInt InitVal = ECD->getInitVal(); 7304 7305 // If it fits into an integer type, force it. Otherwise force it to match 7306 // the enum decl type. 7307 QualType NewTy; 7308 unsigned NewWidth; 7309 bool NewSign; 7310 if (!getLangOptions().CPlusPlus && 7311 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7312 NewTy = Context.IntTy; 7313 NewWidth = IntWidth; 7314 NewSign = true; 7315 } else if (ECD->getType() == BestType) { 7316 // Already the right type! 7317 if (getLangOptions().CPlusPlus) 7318 // C++ [dcl.enum]p4: Following the closing brace of an 7319 // enum-specifier, each enumerator has the type of its 7320 // enumeration. 7321 ECD->setType(EnumType); 7322 continue; 7323 } else { 7324 NewTy = BestType; 7325 NewWidth = BestWidth; 7326 NewSign = BestType->isSignedIntegerType(); 7327 } 7328 7329 // Adjust the APSInt value. 7330 InitVal.extOrTrunc(NewWidth); 7331 InitVal.setIsSigned(NewSign); 7332 ECD->setInitVal(InitVal); 7333 7334 // Adjust the Expr initializer and type. 7335 if (ECD->getInitExpr()) 7336 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7337 CK_IntegralCast, 7338 ECD->getInitExpr(), 7339 /*base paths*/ 0, 7340 VK_RValue)); 7341 if (getLangOptions().CPlusPlus) 7342 // C++ [dcl.enum]p4: Following the closing brace of an 7343 // enum-specifier, each enumerator has the type of its 7344 // enumeration. 7345 ECD->setType(EnumType); 7346 else 7347 ECD->setType(NewTy); 7348 } 7349 7350 Enum->completeDefinition(BestType, BestPromotionType, 7351 NumPositiveBits, NumNegativeBits); 7352} 7353 7354Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7355 StringLiteral *AsmString = cast<StringLiteral>(expr); 7356 7357 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7358 Loc, AsmString); 7359 CurContext->addDecl(New); 7360 return New; 7361} 7362 7363void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7364 SourceLocation PragmaLoc, 7365 SourceLocation NameLoc) { 7366 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7367 7368 if (PrevDecl) { 7369 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7370 } else { 7371 (void)WeakUndeclaredIdentifiers.insert( 7372 std::pair<IdentifierInfo*,WeakInfo> 7373 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7374 } 7375} 7376 7377void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7378 IdentifierInfo* AliasName, 7379 SourceLocation PragmaLoc, 7380 SourceLocation NameLoc, 7381 SourceLocation AliasNameLoc) { 7382 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7383 LookupOrdinaryName); 7384 WeakInfo W = WeakInfo(Name, NameLoc); 7385 7386 if (PrevDecl) { 7387 if (!PrevDecl->hasAttr<AliasAttr>()) 7388 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7389 DeclApplyPragmaWeak(TUScope, ND, W); 7390 } else { 7391 (void)WeakUndeclaredIdentifiers.insert( 7392 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7393 } 7394} 7395