SemaDecl.cpp revision bf6c4651811d95cc7f58e6daf16a8f7b1705d706
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 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 563 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 564 return false; 565 566 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 567 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 568 return false; 569 } else { 570 // 'static inline' functions are used in headers; don't warn. 571 if (FD->getStorageClass() == SC_Static && 572 FD->isInlineSpecified()) 573 return false; 574 } 575 576 if (FD->isThisDeclarationADefinition() && 577 Context.DeclMustBeEmitted(FD)) 578 return false; 579 580 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 581 if (!VD->isFileVarDecl() || 582 VD->getType().isConstant(Context) || 583 Context.DeclMustBeEmitted(VD)) 584 return false; 585 586 if (VD->isStaticDataMember() && 587 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 588 return false; 589 590 } else { 591 return false; 592 } 593 594 // Only warn for unused decls internal to the translation unit. 595 if (D->getLinkage() == ExternalLinkage) 596 return false; 597 598 return true; 599} 600 601void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 602 if (!D) 603 return; 604 605 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 606 const FunctionDecl *First = FD->getFirstDeclaration(); 607 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 608 return; // First should already be in the vector. 609 } 610 611 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 612 const VarDecl *First = VD->getFirstDeclaration(); 613 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 614 return; // First should already be in the vector. 615 } 616 617 if (ShouldWarnIfUnusedFileScopedDecl(D)) 618 UnusedFileScopedDecls.push_back(D); 619 } 620 621static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 622 if (D->isInvalidDecl()) 623 return false; 624 625 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 626 return false; 627 628 // White-list anything that isn't a local variable. 629 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 630 !D->getDeclContext()->isFunctionOrMethod()) 631 return false; 632 633 // Types of valid local variables should be complete, so this should succeed. 634 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 635 636 // White-list anything with an __attribute__((unused)) type. 637 QualType Ty = VD->getType(); 638 639 // Only look at the outermost level of typedef. 640 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 641 if (TT->getDecl()->hasAttr<UnusedAttr>()) 642 return false; 643 } 644 645 // If we failed to complete the type for some reason, or if the type is 646 // dependent, don't diagnose the variable. 647 if (Ty->isIncompleteType() || Ty->isDependentType()) 648 return false; 649 650 if (const TagType *TT = Ty->getAs<TagType>()) { 651 const TagDecl *Tag = TT->getDecl(); 652 if (Tag->hasAttr<UnusedAttr>()) 653 return false; 654 655 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 656 // FIXME: Checking for the presence of a user-declared constructor 657 // isn't completely accurate; we'd prefer to check that the initializer 658 // has no side effects. 659 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 660 return false; 661 } 662 } 663 664 // TODO: __attribute__((unused)) templates? 665 } 666 667 return true; 668} 669 670void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 671 if (!ShouldDiagnoseUnusedDecl(D)) 672 return; 673 674 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 675 Diag(D->getLocation(), diag::warn_unused_exception_param) 676 << D->getDeclName(); 677 else 678 Diag(D->getLocation(), diag::warn_unused_variable) 679 << D->getDeclName(); 680} 681 682void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 683 if (S->decl_empty()) return; 684 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 685 "Scope shouldn't contain decls!"); 686 687 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 688 I != E; ++I) { 689 Decl *TmpD = (*I); 690 assert(TmpD && "This decl didn't get pushed??"); 691 692 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 693 NamedDecl *D = cast<NamedDecl>(TmpD); 694 695 if (!D->getDeclName()) continue; 696 697 // Diagnose unused variables in this scope. 698 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 699 DiagnoseUnusedDecl(D); 700 701 // Remove this name from our lexical scope. 702 IdResolver.RemoveDecl(D); 703 } 704} 705 706/// \brief Look for an Objective-C class in the translation unit. 707/// 708/// \param Id The name of the Objective-C class we're looking for. If 709/// typo-correction fixes this name, the Id will be updated 710/// to the fixed name. 711/// 712/// \param IdLoc The location of the name in the translation unit. 713/// 714/// \param TypoCorrection If true, this routine will attempt typo correction 715/// if there is no class with the given name. 716/// 717/// \returns The declaration of the named Objective-C class, or NULL if the 718/// class could not be found. 719ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 720 SourceLocation IdLoc, 721 bool TypoCorrection) { 722 // The third "scope" argument is 0 since we aren't enabling lazy built-in 723 // creation from this context. 724 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 725 726 if (!IDecl && TypoCorrection) { 727 // Perform typo correction at the given location, but only if we 728 // find an Objective-C class name. 729 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 730 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 731 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 732 Diag(IdLoc, diag::err_undef_interface_suggest) 733 << Id << IDecl->getDeclName() 734 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 735 Diag(IDecl->getLocation(), diag::note_previous_decl) 736 << IDecl->getDeclName(); 737 738 Id = IDecl->getIdentifier(); 739 } 740 } 741 742 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 743} 744 745/// getNonFieldDeclScope - Retrieves the innermost scope, starting 746/// from S, where a non-field would be declared. This routine copes 747/// with the difference between C and C++ scoping rules in structs and 748/// unions. For example, the following code is well-formed in C but 749/// ill-formed in C++: 750/// @code 751/// struct S6 { 752/// enum { BAR } e; 753/// }; 754/// 755/// void test_S6() { 756/// struct S6 a; 757/// a.e = BAR; 758/// } 759/// @endcode 760/// For the declaration of BAR, this routine will return a different 761/// scope. The scope S will be the scope of the unnamed enumeration 762/// within S6. In C++, this routine will return the scope associated 763/// with S6, because the enumeration's scope is a transparent 764/// context but structures can contain non-field names. In C, this 765/// routine will return the translation unit scope, since the 766/// enumeration's scope is a transparent context and structures cannot 767/// contain non-field names. 768Scope *Sema::getNonFieldDeclScope(Scope *S) { 769 while (((S->getFlags() & Scope::DeclScope) == 0) || 770 (S->getEntity() && 771 ((DeclContext *)S->getEntity())->isTransparentContext()) || 772 (S->isClassScope() && !getLangOptions().CPlusPlus)) 773 S = S->getParent(); 774 return S; 775} 776 777/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 778/// file scope. lazily create a decl for it. ForRedeclaration is true 779/// if we're creating this built-in in anticipation of redeclaring the 780/// built-in. 781NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 782 Scope *S, bool ForRedeclaration, 783 SourceLocation Loc) { 784 Builtin::ID BID = (Builtin::ID)bid; 785 786 ASTContext::GetBuiltinTypeError Error; 787 QualType R = Context.GetBuiltinType(BID, Error); 788 switch (Error) { 789 case ASTContext::GE_None: 790 // Okay 791 break; 792 793 case ASTContext::GE_Missing_stdio: 794 if (ForRedeclaration) 795 Diag(Loc, diag::err_implicit_decl_requires_stdio) 796 << Context.BuiltinInfo.GetName(BID); 797 return 0; 798 799 case ASTContext::GE_Missing_setjmp: 800 if (ForRedeclaration) 801 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 802 << Context.BuiltinInfo.GetName(BID); 803 return 0; 804 } 805 806 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 807 Diag(Loc, diag::ext_implicit_lib_function_decl) 808 << Context.BuiltinInfo.GetName(BID) 809 << R; 810 if (Context.BuiltinInfo.getHeaderName(BID) && 811 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 812 != Diagnostic::Ignored) 813 Diag(Loc, diag::note_please_include_header) 814 << Context.BuiltinInfo.getHeaderName(BID) 815 << Context.BuiltinInfo.GetName(BID); 816 } 817 818 FunctionDecl *New = FunctionDecl::Create(Context, 819 Context.getTranslationUnitDecl(), 820 Loc, II, R, /*TInfo=*/0, 821 SC_Extern, 822 SC_None, false, 823 /*hasPrototype=*/true); 824 New->setImplicit(); 825 826 // Create Decl objects for each parameter, adding them to the 827 // FunctionDecl. 828 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 829 llvm::SmallVector<ParmVarDecl*, 16> Params; 830 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 831 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 832 FT->getArgType(i), /*TInfo=*/0, 833 SC_None, SC_None, 0)); 834 New->setParams(Params.data(), Params.size()); 835 } 836 837 AddKnownFunctionAttributes(New); 838 839 // TUScope is the translation-unit scope to insert this function into. 840 // FIXME: This is hideous. We need to teach PushOnScopeChains to 841 // relate Scopes to DeclContexts, and probably eliminate CurContext 842 // entirely, but we're not there yet. 843 DeclContext *SavedContext = CurContext; 844 CurContext = Context.getTranslationUnitDecl(); 845 PushOnScopeChains(New, TUScope); 846 CurContext = SavedContext; 847 return New; 848} 849 850/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 851/// same name and scope as a previous declaration 'Old'. Figure out 852/// how to resolve this situation, merging decls or emitting 853/// diagnostics as appropriate. If there was an error, set New to be invalid. 854/// 855void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 856 // If the new decl is known invalid already, don't bother doing any 857 // merging checks. 858 if (New->isInvalidDecl()) return; 859 860 // Allow multiple definitions for ObjC built-in typedefs. 861 // FIXME: Verify the underlying types are equivalent! 862 if (getLangOptions().ObjC1) { 863 const IdentifierInfo *TypeID = New->getIdentifier(); 864 switch (TypeID->getLength()) { 865 default: break; 866 case 2: 867 if (!TypeID->isStr("id")) 868 break; 869 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 870 // Install the built-in type for 'id', ignoring the current definition. 871 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 872 return; 873 case 5: 874 if (!TypeID->isStr("Class")) 875 break; 876 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 877 // Install the built-in type for 'Class', ignoring the current definition. 878 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 879 return; 880 case 3: 881 if (!TypeID->isStr("SEL")) 882 break; 883 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 884 // Install the built-in type for 'SEL', ignoring the current definition. 885 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 886 return; 887 case 8: 888 if (!TypeID->isStr("Protocol")) 889 break; 890 Context.setObjCProtoType(New->getUnderlyingType()); 891 return; 892 } 893 // Fall through - the typedef name was not a builtin type. 894 } 895 896 // Verify the old decl was also a type. 897 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 898 if (!Old) { 899 Diag(New->getLocation(), diag::err_redefinition_different_kind) 900 << New->getDeclName(); 901 902 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 903 if (OldD->getLocation().isValid()) 904 Diag(OldD->getLocation(), diag::note_previous_definition); 905 906 return New->setInvalidDecl(); 907 } 908 909 // If the old declaration is invalid, just give up here. 910 if (Old->isInvalidDecl()) 911 return New->setInvalidDecl(); 912 913 // Determine the "old" type we'll use for checking and diagnostics. 914 QualType OldType; 915 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 916 OldType = OldTypedef->getUnderlyingType(); 917 else 918 OldType = Context.getTypeDeclType(Old); 919 920 // If the typedef types are not identical, reject them in all languages and 921 // with any extensions enabled. 922 923 if (OldType != New->getUnderlyingType() && 924 Context.getCanonicalType(OldType) != 925 Context.getCanonicalType(New->getUnderlyingType())) { 926 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 927 << New->getUnderlyingType() << OldType; 928 if (Old->getLocation().isValid()) 929 Diag(Old->getLocation(), diag::note_previous_definition); 930 return New->setInvalidDecl(); 931 } 932 933 // The types match. Link up the redeclaration chain if the old 934 // declaration was a typedef. 935 // FIXME: this is a potential source of wierdness if the type 936 // spellings don't match exactly. 937 if (isa<TypedefDecl>(Old)) 938 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 939 940 if (getLangOptions().Microsoft) 941 return; 942 943 if (getLangOptions().CPlusPlus) { 944 // C++ [dcl.typedef]p2: 945 // In a given non-class scope, a typedef specifier can be used to 946 // redefine the name of any type declared in that scope to refer 947 // to the type to which it already refers. 948 if (!isa<CXXRecordDecl>(CurContext)) 949 return; 950 951 // C++0x [dcl.typedef]p4: 952 // In a given class scope, a typedef specifier can be used to redefine 953 // any class-name declared in that scope that is not also a typedef-name 954 // to refer to the type to which it already refers. 955 // 956 // This wording came in via DR424, which was a correction to the 957 // wording in DR56, which accidentally banned code like: 958 // 959 // struct S { 960 // typedef struct A { } A; 961 // }; 962 // 963 // in the C++03 standard. We implement the C++0x semantics, which 964 // allow the above but disallow 965 // 966 // struct S { 967 // typedef int I; 968 // typedef int I; 969 // }; 970 // 971 // since that was the intent of DR56. 972 if (!isa<TypedefDecl >(Old)) 973 return; 974 975 Diag(New->getLocation(), diag::err_redefinition) 976 << New->getDeclName(); 977 Diag(Old->getLocation(), diag::note_previous_definition); 978 return New->setInvalidDecl(); 979 } 980 981 // If we have a redefinition of a typedef in C, emit a warning. This warning 982 // is normally mapped to an error, but can be controlled with 983 // -Wtypedef-redefinition. If either the original or the redefinition is 984 // in a system header, don't emit this for compatibility with GCC. 985 if (getDiagnostics().getSuppressSystemWarnings() && 986 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 987 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 988 return; 989 990 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 991 << New->getDeclName(); 992 Diag(Old->getLocation(), diag::note_previous_definition); 993 return; 994} 995 996/// DeclhasAttr - returns true if decl Declaration already has the target 997/// attribute. 998static bool 999DeclHasAttr(const Decl *D, const Attr *A) { 1000 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1001 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1002 if ((*i)->getKind() == A->getKind()) { 1003 // FIXME: Don't hardcode this check 1004 if (OA && isa<OwnershipAttr>(*i)) 1005 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1006 return true; 1007 } 1008 1009 return false; 1010} 1011 1012/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1013static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1014 if (!Old->hasAttrs()) 1015 return; 1016 // Ensure that any moving of objects within the allocated map is done before 1017 // we process them. 1018 if (!New->hasAttrs()) 1019 New->setAttrs(AttrVec()); 1020 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1021 ++i) { 1022 // FIXME: Make this more general than just checking for Overloadable. 1023 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1024 Attr *NewAttr = (*i)->clone(C); 1025 NewAttr->setInherited(true); 1026 New->addAttr(NewAttr); 1027 } 1028 } 1029} 1030 1031namespace { 1032 1033/// Used in MergeFunctionDecl to keep track of function parameters in 1034/// C. 1035struct GNUCompatibleParamWarning { 1036 ParmVarDecl *OldParm; 1037 ParmVarDecl *NewParm; 1038 QualType PromotedType; 1039}; 1040 1041} 1042 1043/// getSpecialMember - get the special member enum for a method. 1044Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1045 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1046 if (Ctor->isCopyConstructor()) 1047 return Sema::CXXCopyConstructor; 1048 1049 return Sema::CXXConstructor; 1050 } 1051 1052 if (isa<CXXDestructorDecl>(MD)) 1053 return Sema::CXXDestructor; 1054 1055 assert(MD->isCopyAssignmentOperator() && 1056 "Must have copy assignment operator"); 1057 return Sema::CXXCopyAssignment; 1058} 1059 1060/// canRedefineFunction - checks if a function can be redefined. Currently, 1061/// only extern inline functions can be redefined, and even then only in 1062/// GNU89 mode. 1063static bool canRedefineFunction(const FunctionDecl *FD, 1064 const LangOptions& LangOpts) { 1065 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1066 FD->isInlineSpecified() && 1067 FD->getStorageClass() == SC_Extern); 1068} 1069 1070/// MergeFunctionDecl - We just parsed a function 'New' from 1071/// declarator D which has the same name and scope as a previous 1072/// declaration 'Old'. Figure out how to resolve this situation, 1073/// merging decls or emitting diagnostics as appropriate. 1074/// 1075/// In C++, New and Old must be declarations that are not 1076/// overloaded. Use IsOverload to determine whether New and Old are 1077/// overloaded, and to select the Old declaration that New should be 1078/// merged with. 1079/// 1080/// Returns true if there was an error, false otherwise. 1081bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1082 // Verify the old decl was also a function. 1083 FunctionDecl *Old = 0; 1084 if (FunctionTemplateDecl *OldFunctionTemplate 1085 = dyn_cast<FunctionTemplateDecl>(OldD)) 1086 Old = OldFunctionTemplate->getTemplatedDecl(); 1087 else 1088 Old = dyn_cast<FunctionDecl>(OldD); 1089 if (!Old) { 1090 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1091 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1092 Diag(Shadow->getTargetDecl()->getLocation(), 1093 diag::note_using_decl_target); 1094 Diag(Shadow->getUsingDecl()->getLocation(), 1095 diag::note_using_decl) << 0; 1096 return true; 1097 } 1098 1099 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1100 << New->getDeclName(); 1101 Diag(OldD->getLocation(), diag::note_previous_definition); 1102 return true; 1103 } 1104 1105 // Determine whether the previous declaration was a definition, 1106 // implicit declaration, or a declaration. 1107 diag::kind PrevDiag; 1108 if (Old->isThisDeclarationADefinition()) 1109 PrevDiag = diag::note_previous_definition; 1110 else if (Old->isImplicit()) 1111 PrevDiag = diag::note_previous_implicit_declaration; 1112 else 1113 PrevDiag = diag::note_previous_declaration; 1114 1115 QualType OldQType = Context.getCanonicalType(Old->getType()); 1116 QualType NewQType = Context.getCanonicalType(New->getType()); 1117 1118 // Don't complain about this if we're in GNU89 mode and the old function 1119 // is an extern inline function. 1120 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1121 New->getStorageClass() == SC_Static && 1122 Old->getStorageClass() != SC_Static && 1123 !canRedefineFunction(Old, getLangOptions())) { 1124 Diag(New->getLocation(), diag::err_static_non_static) 1125 << New; 1126 Diag(Old->getLocation(), PrevDiag); 1127 return true; 1128 } 1129 1130 // If a function is first declared with a calling convention, but is 1131 // later declared or defined without one, the second decl assumes the 1132 // calling convention of the first. 1133 // 1134 // For the new decl, we have to look at the NON-canonical type to tell the 1135 // difference between a function that really doesn't have a calling 1136 // convention and one that is declared cdecl. That's because in 1137 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1138 // because it is the default calling convention. 1139 // 1140 // Note also that we DO NOT return at this point, because we still have 1141 // other tests to run. 1142 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1143 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1144 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1145 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1146 if (OldTypeInfo.getCC() != CC_Default && 1147 NewTypeInfo.getCC() == CC_Default) { 1148 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1149 New->setType(NewQType); 1150 NewQType = Context.getCanonicalType(NewQType); 1151 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1152 NewTypeInfo.getCC())) { 1153 // Calling conventions really aren't compatible, so complain. 1154 Diag(New->getLocation(), diag::err_cconv_change) 1155 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1156 << (OldTypeInfo.getCC() == CC_Default) 1157 << (OldTypeInfo.getCC() == CC_Default ? "" : 1158 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1159 Diag(Old->getLocation(), diag::note_previous_declaration); 1160 return true; 1161 } 1162 1163 // FIXME: diagnose the other way around? 1164 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1165 NewQType = Context.getNoReturnType(NewQType); 1166 New->setType(NewQType); 1167 assert(NewQType.isCanonical()); 1168 } 1169 1170 // Merge regparm attribute. 1171 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1172 if (NewType->getRegParmType()) { 1173 Diag(New->getLocation(), diag::err_regparm_mismatch) 1174 << NewType->getRegParmType() 1175 << OldType->getRegParmType(); 1176 Diag(Old->getLocation(), diag::note_previous_declaration); 1177 return true; 1178 } 1179 1180 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1181 New->setType(NewQType); 1182 assert(NewQType.isCanonical()); 1183 } 1184 1185 if (getLangOptions().CPlusPlus) { 1186 // (C++98 13.1p2): 1187 // Certain function declarations cannot be overloaded: 1188 // -- Function declarations that differ only in the return type 1189 // cannot be overloaded. 1190 QualType OldReturnType 1191 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1192 QualType NewReturnType 1193 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1194 QualType ResQT; 1195 if (OldReturnType != NewReturnType) { 1196 if (NewReturnType->isObjCObjectPointerType() 1197 && OldReturnType->isObjCObjectPointerType()) 1198 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1199 if (ResQT.isNull()) { 1200 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1201 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1202 return true; 1203 } 1204 else 1205 NewQType = ResQT; 1206 } 1207 1208 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1209 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1210 if (OldMethod && NewMethod) { 1211 // Preserve triviality. 1212 NewMethod->setTrivial(OldMethod->isTrivial()); 1213 1214 bool isFriend = NewMethod->getFriendObjectKind(); 1215 1216 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1217 // -- Member function declarations with the same name and the 1218 // same parameter types cannot be overloaded if any of them 1219 // is a static member function declaration. 1220 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1221 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1222 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1223 return true; 1224 } 1225 1226 // C++ [class.mem]p1: 1227 // [...] A member shall not be declared twice in the 1228 // member-specification, except that a nested class or member 1229 // class template can be declared and then later defined. 1230 unsigned NewDiag; 1231 if (isa<CXXConstructorDecl>(OldMethod)) 1232 NewDiag = diag::err_constructor_redeclared; 1233 else if (isa<CXXDestructorDecl>(NewMethod)) 1234 NewDiag = diag::err_destructor_redeclared; 1235 else if (isa<CXXConversionDecl>(NewMethod)) 1236 NewDiag = diag::err_conv_function_redeclared; 1237 else 1238 NewDiag = diag::err_member_redeclared; 1239 1240 Diag(New->getLocation(), NewDiag); 1241 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1242 1243 // Complain if this is an explicit declaration of a special 1244 // member that was initially declared implicitly. 1245 // 1246 // As an exception, it's okay to befriend such methods in order 1247 // to permit the implicit constructor/destructor/operator calls. 1248 } else if (OldMethod->isImplicit()) { 1249 if (isFriend) { 1250 NewMethod->setImplicit(); 1251 } else { 1252 Diag(NewMethod->getLocation(), 1253 diag::err_definition_of_implicitly_declared_member) 1254 << New << getSpecialMember(OldMethod); 1255 return true; 1256 } 1257 } 1258 } 1259 1260 // (C++98 8.3.5p3): 1261 // All declarations for a function shall agree exactly in both the 1262 // return type and the parameter-type-list. 1263 // attributes should be ignored when comparing. 1264 if (Context.getNoReturnType(OldQType, false) == 1265 Context.getNoReturnType(NewQType, false)) 1266 return MergeCompatibleFunctionDecls(New, Old); 1267 1268 // Fall through for conflicting redeclarations and redefinitions. 1269 } 1270 1271 // C: Function types need to be compatible, not identical. This handles 1272 // duplicate function decls like "void f(int); void f(enum X);" properly. 1273 if (!getLangOptions().CPlusPlus && 1274 Context.typesAreCompatible(OldQType, NewQType)) { 1275 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1276 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1277 const FunctionProtoType *OldProto = 0; 1278 if (isa<FunctionNoProtoType>(NewFuncType) && 1279 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1280 // The old declaration provided a function prototype, but the 1281 // new declaration does not. Merge in the prototype. 1282 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1283 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1284 OldProto->arg_type_end()); 1285 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1286 ParamTypes.data(), ParamTypes.size(), 1287 OldProto->isVariadic(), 1288 OldProto->getTypeQuals(), 1289 false, false, 0, 0, 1290 OldProto->getExtInfo()); 1291 New->setType(NewQType); 1292 New->setHasInheritedPrototype(); 1293 1294 // Synthesize a parameter for each argument type. 1295 llvm::SmallVector<ParmVarDecl*, 16> Params; 1296 for (FunctionProtoType::arg_type_iterator 1297 ParamType = OldProto->arg_type_begin(), 1298 ParamEnd = OldProto->arg_type_end(); 1299 ParamType != ParamEnd; ++ParamType) { 1300 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1301 SourceLocation(), 0, 1302 *ParamType, /*TInfo=*/0, 1303 SC_None, SC_None, 1304 0); 1305 Param->setImplicit(); 1306 Params.push_back(Param); 1307 } 1308 1309 New->setParams(Params.data(), Params.size()); 1310 } 1311 1312 return MergeCompatibleFunctionDecls(New, Old); 1313 } 1314 1315 // GNU C permits a K&R definition to follow a prototype declaration 1316 // if the declared types of the parameters in the K&R definition 1317 // match the types in the prototype declaration, even when the 1318 // promoted types of the parameters from the K&R definition differ 1319 // from the types in the prototype. GCC then keeps the types from 1320 // the prototype. 1321 // 1322 // If a variadic prototype is followed by a non-variadic K&R definition, 1323 // the K&R definition becomes variadic. This is sort of an edge case, but 1324 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1325 // C99 6.9.1p8. 1326 if (!getLangOptions().CPlusPlus && 1327 Old->hasPrototype() && !New->hasPrototype() && 1328 New->getType()->getAs<FunctionProtoType>() && 1329 Old->getNumParams() == New->getNumParams()) { 1330 llvm::SmallVector<QualType, 16> ArgTypes; 1331 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1332 const FunctionProtoType *OldProto 1333 = Old->getType()->getAs<FunctionProtoType>(); 1334 const FunctionProtoType *NewProto 1335 = New->getType()->getAs<FunctionProtoType>(); 1336 1337 // Determine whether this is the GNU C extension. 1338 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1339 NewProto->getResultType()); 1340 bool LooseCompatible = !MergedReturn.isNull(); 1341 for (unsigned Idx = 0, End = Old->getNumParams(); 1342 LooseCompatible && Idx != End; ++Idx) { 1343 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1344 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1345 if (Context.typesAreCompatible(OldParm->getType(), 1346 NewProto->getArgType(Idx))) { 1347 ArgTypes.push_back(NewParm->getType()); 1348 } else if (Context.typesAreCompatible(OldParm->getType(), 1349 NewParm->getType(), 1350 /*CompareUnqualified=*/true)) { 1351 GNUCompatibleParamWarning Warn 1352 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1353 Warnings.push_back(Warn); 1354 ArgTypes.push_back(NewParm->getType()); 1355 } else 1356 LooseCompatible = false; 1357 } 1358 1359 if (LooseCompatible) { 1360 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1361 Diag(Warnings[Warn].NewParm->getLocation(), 1362 diag::ext_param_promoted_not_compatible_with_prototype) 1363 << Warnings[Warn].PromotedType 1364 << Warnings[Warn].OldParm->getType(); 1365 if (Warnings[Warn].OldParm->getLocation().isValid()) 1366 Diag(Warnings[Warn].OldParm->getLocation(), 1367 diag::note_previous_declaration); 1368 } 1369 1370 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1371 ArgTypes.size(), 1372 OldProto->isVariadic(), 0, 1373 false, false, 0, 0, 1374 OldProto->getExtInfo())); 1375 return MergeCompatibleFunctionDecls(New, Old); 1376 } 1377 1378 // Fall through to diagnose conflicting types. 1379 } 1380 1381 // A function that has already been declared has been redeclared or defined 1382 // with a different type- show appropriate diagnostic 1383 if (unsigned BuiltinID = Old->getBuiltinID()) { 1384 // The user has declared a builtin function with an incompatible 1385 // signature. 1386 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1387 // The function the user is redeclaring is a library-defined 1388 // function like 'malloc' or 'printf'. Warn about the 1389 // redeclaration, then pretend that we don't know about this 1390 // library built-in. 1391 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1392 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1393 << Old << Old->getType(); 1394 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1395 Old->setInvalidDecl(); 1396 return false; 1397 } 1398 1399 PrevDiag = diag::note_previous_builtin_declaration; 1400 } 1401 1402 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1403 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1404 return true; 1405} 1406 1407/// \brief Completes the merge of two function declarations that are 1408/// known to be compatible. 1409/// 1410/// This routine handles the merging of attributes and other 1411/// properties of function declarations form the old declaration to 1412/// the new declaration, once we know that New is in fact a 1413/// redeclaration of Old. 1414/// 1415/// \returns false 1416bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1417 // Merge the attributes 1418 MergeDeclAttributes(New, Old, Context); 1419 1420 // Merge the storage class. 1421 if (Old->getStorageClass() != SC_Extern && 1422 Old->getStorageClass() != SC_None) 1423 New->setStorageClass(Old->getStorageClass()); 1424 1425 // Merge "pure" flag. 1426 if (Old->isPure()) 1427 New->setPure(); 1428 1429 // Merge the "deleted" flag. 1430 if (Old->isDeleted()) 1431 New->setDeleted(); 1432 1433 if (getLangOptions().CPlusPlus) 1434 return MergeCXXFunctionDecl(New, Old); 1435 1436 return false; 1437} 1438 1439/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1440/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1441/// situation, merging decls or emitting diagnostics as appropriate. 1442/// 1443/// Tentative definition rules (C99 6.9.2p2) are checked by 1444/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1445/// definitions here, since the initializer hasn't been attached. 1446/// 1447void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1448 // If the new decl is already invalid, don't do any other checking. 1449 if (New->isInvalidDecl()) 1450 return; 1451 1452 // Verify the old decl was also a variable. 1453 VarDecl *Old = 0; 1454 if (!Previous.isSingleResult() || 1455 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1456 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1457 << New->getDeclName(); 1458 Diag(Previous.getRepresentativeDecl()->getLocation(), 1459 diag::note_previous_definition); 1460 return New->setInvalidDecl(); 1461 } 1462 1463 // C++ [class.mem]p1: 1464 // A member shall not be declared twice in the member-specification [...] 1465 // 1466 // Here, we need only consider static data members. 1467 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1468 Diag(New->getLocation(), diag::err_duplicate_member) 1469 << New->getIdentifier(); 1470 Diag(Old->getLocation(), diag::note_previous_declaration); 1471 New->setInvalidDecl(); 1472 } 1473 1474 MergeDeclAttributes(New, Old, Context); 1475 1476 // Merge the types 1477 QualType MergedT; 1478 if (getLangOptions().CPlusPlus) { 1479 if (Context.hasSameType(New->getType(), Old->getType())) 1480 MergedT = New->getType(); 1481 // C++ [basic.link]p10: 1482 // [...] the types specified by all declarations referring to a given 1483 // object or function shall be identical, except that declarations for an 1484 // array object can specify array types that differ by the presence or 1485 // absence of a major array bound (8.3.4). 1486 else if (Old->getType()->isIncompleteArrayType() && 1487 New->getType()->isArrayType()) { 1488 CanQual<ArrayType> OldArray 1489 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1490 CanQual<ArrayType> NewArray 1491 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1492 if (OldArray->getElementType() == NewArray->getElementType()) 1493 MergedT = New->getType(); 1494 } else if (Old->getType()->isArrayType() && 1495 New->getType()->isIncompleteArrayType()) { 1496 CanQual<ArrayType> OldArray 1497 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1498 CanQual<ArrayType> NewArray 1499 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1500 if (OldArray->getElementType() == NewArray->getElementType()) 1501 MergedT = Old->getType(); 1502 } else if (New->getType()->isObjCObjectPointerType() 1503 && Old->getType()->isObjCObjectPointerType()) { 1504 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1505 } 1506 } else { 1507 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1508 } 1509 if (MergedT.isNull()) { 1510 Diag(New->getLocation(), diag::err_redefinition_different_type) 1511 << New->getDeclName(); 1512 Diag(Old->getLocation(), diag::note_previous_definition); 1513 return New->setInvalidDecl(); 1514 } 1515 New->setType(MergedT); 1516 1517 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1518 if (New->getStorageClass() == SC_Static && 1519 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1520 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1521 Diag(Old->getLocation(), diag::note_previous_definition); 1522 return New->setInvalidDecl(); 1523 } 1524 // C99 6.2.2p4: 1525 // For an identifier declared with the storage-class specifier 1526 // extern in a scope in which a prior declaration of that 1527 // identifier is visible,23) if the prior declaration specifies 1528 // internal or external linkage, the linkage of the identifier at 1529 // the later declaration is the same as the linkage specified at 1530 // the prior declaration. If no prior declaration is visible, or 1531 // if the prior declaration specifies no linkage, then the 1532 // identifier has external linkage. 1533 if (New->hasExternalStorage() && Old->hasLinkage()) 1534 /* Okay */; 1535 else if (New->getStorageClass() != SC_Static && 1536 Old->getStorageClass() == SC_Static) { 1537 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1538 Diag(Old->getLocation(), diag::note_previous_definition); 1539 return New->setInvalidDecl(); 1540 } 1541 1542 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1543 1544 // FIXME: The test for external storage here seems wrong? We still 1545 // need to check for mismatches. 1546 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1547 // Don't complain about out-of-line definitions of static members. 1548 !(Old->getLexicalDeclContext()->isRecord() && 1549 !New->getLexicalDeclContext()->isRecord())) { 1550 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1551 Diag(Old->getLocation(), diag::note_previous_definition); 1552 return New->setInvalidDecl(); 1553 } 1554 1555 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1556 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1557 Diag(Old->getLocation(), diag::note_previous_definition); 1558 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1559 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1560 Diag(Old->getLocation(), diag::note_previous_definition); 1561 } 1562 1563 // C++ doesn't have tentative definitions, so go right ahead and check here. 1564 const VarDecl *Def; 1565 if (getLangOptions().CPlusPlus && 1566 New->isThisDeclarationADefinition() == VarDecl::Definition && 1567 (Def = Old->getDefinition())) { 1568 Diag(New->getLocation(), diag::err_redefinition) 1569 << New->getDeclName(); 1570 Diag(Def->getLocation(), diag::note_previous_definition); 1571 New->setInvalidDecl(); 1572 return; 1573 } 1574 // c99 6.2.2 P4. 1575 // For an identifier declared with the storage-class specifier extern in a 1576 // scope in which a prior declaration of that identifier is visible, if 1577 // the prior declaration specifies internal or external linkage, the linkage 1578 // of the identifier at the later declaration is the same as the linkage 1579 // specified at the prior declaration. 1580 // FIXME. revisit this code. 1581 if (New->hasExternalStorage() && 1582 Old->getLinkage() == InternalLinkage && 1583 New->getDeclContext() == Old->getDeclContext()) 1584 New->setStorageClass(Old->getStorageClass()); 1585 1586 // Keep a chain of previous declarations. 1587 New->setPreviousDeclaration(Old); 1588 1589 // Inherit access appropriately. 1590 New->setAccess(Old->getAccess()); 1591} 1592 1593/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1594/// no declarator (e.g. "struct foo;") is parsed. 1595Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1596 DeclSpec &DS) { 1597 // FIXME: Error on inline/virtual/explicit 1598 // FIXME: Warn on useless __thread 1599 // FIXME: Warn on useless const/volatile 1600 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1601 // FIXME: Warn on useless attributes 1602 Decl *TagD = 0; 1603 TagDecl *Tag = 0; 1604 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1605 DS.getTypeSpecType() == DeclSpec::TST_struct || 1606 DS.getTypeSpecType() == DeclSpec::TST_union || 1607 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1608 TagD = DS.getRepAsDecl(); 1609 1610 if (!TagD) // We probably had an error 1611 return 0; 1612 1613 // Note that the above type specs guarantee that the 1614 // type rep is a Decl, whereas in many of the others 1615 // it's a Type. 1616 Tag = dyn_cast<TagDecl>(TagD); 1617 } 1618 1619 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1620 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1621 // or incomplete types shall not be restrict-qualified." 1622 if (TypeQuals & DeclSpec::TQ_restrict) 1623 Diag(DS.getRestrictSpecLoc(), 1624 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1625 << DS.getSourceRange(); 1626 } 1627 1628 if (DS.isFriendSpecified()) { 1629 // If we're dealing with a decl but not a TagDecl, assume that 1630 // whatever routines created it handled the friendship aspect. 1631 if (TagD && !Tag) 1632 return 0; 1633 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1634 } 1635 1636 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1637 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1638 1639 if (!Record->getDeclName() && Record->isDefinition() && 1640 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1641 if (getLangOptions().CPlusPlus || 1642 Record->getDeclContext()->isRecord()) 1643 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1644 1645 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1646 << DS.getSourceRange(); 1647 } 1648 1649 // Microsoft allows unnamed struct/union fields. Don't complain 1650 // about them. 1651 // FIXME: Should we support Microsoft's extensions in this area? 1652 if (Record->getDeclName() && getLangOptions().Microsoft) 1653 return Tag; 1654 } 1655 1656 if (getLangOptions().CPlusPlus && 1657 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1658 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1659 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1660 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1661 Diag(Enum->getLocation(), diag::ext_no_declarators) 1662 << DS.getSourceRange(); 1663 1664 if (!DS.isMissingDeclaratorOk() && 1665 DS.getTypeSpecType() != DeclSpec::TST_error) { 1666 // Warn about typedefs of enums without names, since this is an 1667 // extension in both Microsoft and GNU. 1668 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1669 Tag && isa<EnumDecl>(Tag)) { 1670 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1671 << DS.getSourceRange(); 1672 return Tag; 1673 } 1674 1675 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1676 << DS.getSourceRange(); 1677 } 1678 1679 return TagD; 1680} 1681 1682/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1683/// builds a statement for it and returns it so it is evaluated. 1684StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1685 StmtResult R; 1686 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1687 Expr *Exp = DS.getRepAsExpr(); 1688 QualType Ty = Exp->getType(); 1689 if (Ty->isPointerType()) { 1690 do 1691 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1692 while (Ty->isPointerType()); 1693 } 1694 if (Ty->isVariableArrayType()) { 1695 R = ActOnExprStmt(MakeFullExpr(Exp)); 1696 } 1697 } 1698 return R; 1699} 1700 1701/// We are trying to inject an anonymous member into the given scope; 1702/// check if there's an existing declaration that can't be overloaded. 1703/// 1704/// \return true if this is a forbidden redeclaration 1705static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1706 Scope *S, 1707 DeclContext *Owner, 1708 DeclarationName Name, 1709 SourceLocation NameLoc, 1710 unsigned diagnostic) { 1711 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1712 Sema::ForRedeclaration); 1713 if (!SemaRef.LookupName(R, S)) return false; 1714 1715 if (R.getAsSingle<TagDecl>()) 1716 return false; 1717 1718 // Pick a representative declaration. 1719 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1720 assert(PrevDecl && "Expected a non-null Decl"); 1721 1722 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1723 return false; 1724 1725 SemaRef.Diag(NameLoc, diagnostic) << Name; 1726 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1727 1728 return true; 1729} 1730 1731/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1732/// anonymous struct or union AnonRecord into the owning context Owner 1733/// and scope S. This routine will be invoked just after we realize 1734/// that an unnamed union or struct is actually an anonymous union or 1735/// struct, e.g., 1736/// 1737/// @code 1738/// union { 1739/// int i; 1740/// float f; 1741/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1742/// // f into the surrounding scope.x 1743/// @endcode 1744/// 1745/// This routine is recursive, injecting the names of nested anonymous 1746/// structs/unions into the owning context and scope as well. 1747static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1748 DeclContext *Owner, 1749 RecordDecl *AnonRecord, 1750 AccessSpecifier AS) { 1751 unsigned diagKind 1752 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1753 : diag::err_anonymous_struct_member_redecl; 1754 1755 bool Invalid = false; 1756 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1757 FEnd = AnonRecord->field_end(); 1758 F != FEnd; ++F) { 1759 if ((*F)->getDeclName()) { 1760 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1761 (*F)->getLocation(), diagKind)) { 1762 // C++ [class.union]p2: 1763 // The names of the members of an anonymous union shall be 1764 // distinct from the names of any other entity in the 1765 // scope in which the anonymous union is declared. 1766 Invalid = true; 1767 } else { 1768 // C++ [class.union]p2: 1769 // For the purpose of name lookup, after the anonymous union 1770 // definition, the members of the anonymous union are 1771 // considered to have been defined in the scope in which the 1772 // anonymous union is declared. 1773 Owner->makeDeclVisibleInContext(*F); 1774 S->AddDecl(*F); 1775 SemaRef.IdResolver.AddDecl(*F); 1776 1777 // That includes picking up the appropriate access specifier. 1778 if (AS != AS_none) (*F)->setAccess(AS); 1779 } 1780 } else if (const RecordType *InnerRecordType 1781 = (*F)->getType()->getAs<RecordType>()) { 1782 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1783 if (InnerRecord->isAnonymousStructOrUnion()) 1784 Invalid = Invalid || 1785 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1786 InnerRecord, AS); 1787 } 1788 } 1789 1790 return Invalid; 1791} 1792 1793/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1794/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1795/// illegal input values are mapped to SC_None. 1796static StorageClass 1797StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1798 switch (StorageClassSpec) { 1799 case DeclSpec::SCS_unspecified: return SC_None; 1800 case DeclSpec::SCS_extern: return SC_Extern; 1801 case DeclSpec::SCS_static: return SC_Static; 1802 case DeclSpec::SCS_auto: return SC_Auto; 1803 case DeclSpec::SCS_register: return SC_Register; 1804 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1805 // Illegal SCSs map to None: error reporting is up to the caller. 1806 case DeclSpec::SCS_mutable: // Fall through. 1807 case DeclSpec::SCS_typedef: return SC_None; 1808 } 1809 llvm_unreachable("unknown storage class specifier"); 1810} 1811 1812/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1813/// a StorageClass. Any error reporting is up to the caller: 1814/// illegal input values are mapped to SC_None. 1815static StorageClass 1816StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1817 switch (StorageClassSpec) { 1818 case DeclSpec::SCS_unspecified: return SC_None; 1819 case DeclSpec::SCS_extern: return SC_Extern; 1820 case DeclSpec::SCS_static: return SC_Static; 1821 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1822 // Illegal SCSs map to None: error reporting is up to the caller. 1823 case DeclSpec::SCS_auto: // Fall through. 1824 case DeclSpec::SCS_mutable: // Fall through. 1825 case DeclSpec::SCS_register: // Fall through. 1826 case DeclSpec::SCS_typedef: return SC_None; 1827 } 1828 llvm_unreachable("unknown storage class specifier"); 1829} 1830 1831/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1832/// anonymous structure or union. Anonymous unions are a C++ feature 1833/// (C++ [class.union]) and a GNU C extension; anonymous structures 1834/// are a GNU C and GNU C++ extension. 1835Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1836 AccessSpecifier AS, 1837 RecordDecl *Record) { 1838 DeclContext *Owner = Record->getDeclContext(); 1839 1840 // Diagnose whether this anonymous struct/union is an extension. 1841 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1842 Diag(Record->getLocation(), diag::ext_anonymous_union); 1843 else if (!Record->isUnion()) 1844 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1845 1846 // C and C++ require different kinds of checks for anonymous 1847 // structs/unions. 1848 bool Invalid = false; 1849 if (getLangOptions().CPlusPlus) { 1850 const char* PrevSpec = 0; 1851 unsigned DiagID; 1852 // C++ [class.union]p3: 1853 // Anonymous unions declared in a named namespace or in the 1854 // global namespace shall be declared static. 1855 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1856 (isa<TranslationUnitDecl>(Owner) || 1857 (isa<NamespaceDecl>(Owner) && 1858 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1859 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1860 Invalid = true; 1861 1862 // Recover by adding 'static'. 1863 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1864 PrevSpec, DiagID); 1865 } 1866 // C++ [class.union]p3: 1867 // A storage class is not allowed in a declaration of an 1868 // anonymous union in a class scope. 1869 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1870 isa<RecordDecl>(Owner)) { 1871 Diag(DS.getStorageClassSpecLoc(), 1872 diag::err_anonymous_union_with_storage_spec); 1873 Invalid = true; 1874 1875 // Recover by removing the storage specifier. 1876 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1877 PrevSpec, DiagID); 1878 } 1879 1880 // C++ [class.union]p2: 1881 // The member-specification of an anonymous union shall only 1882 // define non-static data members. [Note: nested types and 1883 // functions cannot be declared within an anonymous union. ] 1884 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1885 MemEnd = Record->decls_end(); 1886 Mem != MemEnd; ++Mem) { 1887 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1888 // C++ [class.union]p3: 1889 // An anonymous union shall not have private or protected 1890 // members (clause 11). 1891 assert(FD->getAccess() != AS_none); 1892 if (FD->getAccess() != AS_public) { 1893 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1894 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1895 Invalid = true; 1896 } 1897 1898 if (CheckNontrivialField(FD)) 1899 Invalid = true; 1900 } else if ((*Mem)->isImplicit()) { 1901 // Any implicit members are fine. 1902 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1903 // This is a type that showed up in an 1904 // elaborated-type-specifier inside the anonymous struct or 1905 // union, but which actually declares a type outside of the 1906 // anonymous struct or union. It's okay. 1907 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1908 if (!MemRecord->isAnonymousStructOrUnion() && 1909 MemRecord->getDeclName()) { 1910 // Visual C++ allows type definition in anonymous struct or union. 1911 if (getLangOptions().Microsoft) 1912 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 1913 << (int)Record->isUnion(); 1914 else { 1915 // This is a nested type declaration. 1916 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1917 << (int)Record->isUnion(); 1918 Invalid = true; 1919 } 1920 } 1921 } else if (isa<AccessSpecDecl>(*Mem)) { 1922 // Any access specifier is fine. 1923 } else { 1924 // We have something that isn't a non-static data 1925 // member. Complain about it. 1926 unsigned DK = diag::err_anonymous_record_bad_member; 1927 if (isa<TypeDecl>(*Mem)) 1928 DK = diag::err_anonymous_record_with_type; 1929 else if (isa<FunctionDecl>(*Mem)) 1930 DK = diag::err_anonymous_record_with_function; 1931 else if (isa<VarDecl>(*Mem)) 1932 DK = diag::err_anonymous_record_with_static; 1933 1934 // Visual C++ allows type definition in anonymous struct or union. 1935 if (getLangOptions().Microsoft && 1936 DK == diag::err_anonymous_record_with_type) 1937 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 1938 << (int)Record->isUnion(); 1939 else { 1940 Diag((*Mem)->getLocation(), DK) 1941 << (int)Record->isUnion(); 1942 Invalid = true; 1943 } 1944 } 1945 } 1946 } 1947 1948 if (!Record->isUnion() && !Owner->isRecord()) { 1949 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1950 << (int)getLangOptions().CPlusPlus; 1951 Invalid = true; 1952 } 1953 1954 // Mock up a declarator. 1955 Declarator Dc(DS, Declarator::TypeNameContext); 1956 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1957 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1958 1959 // Create a declaration for this anonymous struct/union. 1960 NamedDecl *Anon = 0; 1961 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1962 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1963 /*IdentifierInfo=*/0, 1964 Context.getTypeDeclType(Record), 1965 TInfo, 1966 /*BitWidth=*/0, /*Mutable=*/false); 1967 Anon->setAccess(AS); 1968 if (getLangOptions().CPlusPlus) 1969 FieldCollector->Add(cast<FieldDecl>(Anon)); 1970 } else { 1971 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1972 assert(SCSpec != DeclSpec::SCS_typedef && 1973 "Parser allowed 'typedef' as storage class VarDecl."); 1974 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1975 if (SCSpec == DeclSpec::SCS_mutable) { 1976 // mutable can only appear on non-static class members, so it's always 1977 // an error here 1978 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1979 Invalid = true; 1980 SC = SC_None; 1981 } 1982 SCSpec = DS.getStorageClassSpecAsWritten(); 1983 VarDecl::StorageClass SCAsWritten 1984 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1985 1986 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1987 /*IdentifierInfo=*/0, 1988 Context.getTypeDeclType(Record), 1989 TInfo, SC, SCAsWritten); 1990 } 1991 Anon->setImplicit(); 1992 1993 // Add the anonymous struct/union object to the current 1994 // context. We'll be referencing this object when we refer to one of 1995 // its members. 1996 Owner->addDecl(Anon); 1997 1998 // Inject the members of the anonymous struct/union into the owning 1999 // context and into the identifier resolver chain for name lookup 2000 // purposes. 2001 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 2002 Invalid = true; 2003 2004 // Mark this as an anonymous struct/union type. Note that we do not 2005 // do this until after we have already checked and injected the 2006 // members of this anonymous struct/union type, because otherwise 2007 // the members could be injected twice: once by DeclContext when it 2008 // builds its lookup table, and once by 2009 // InjectAnonymousStructOrUnionMembers. 2010 Record->setAnonymousStructOrUnion(true); 2011 2012 if (Invalid) 2013 Anon->setInvalidDecl(); 2014 2015 return Anon; 2016} 2017 2018 2019/// GetNameForDeclarator - Determine the full declaration name for the 2020/// given Declarator. 2021DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2022 return GetNameFromUnqualifiedId(D.getName()); 2023} 2024 2025/// \brief Retrieves the declaration name from a parsed unqualified-id. 2026DeclarationNameInfo 2027Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2028 DeclarationNameInfo NameInfo; 2029 NameInfo.setLoc(Name.StartLocation); 2030 2031 switch (Name.getKind()) { 2032 2033 case UnqualifiedId::IK_Identifier: 2034 NameInfo.setName(Name.Identifier); 2035 NameInfo.setLoc(Name.StartLocation); 2036 return NameInfo; 2037 2038 case UnqualifiedId::IK_OperatorFunctionId: 2039 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2040 Name.OperatorFunctionId.Operator)); 2041 NameInfo.setLoc(Name.StartLocation); 2042 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2043 = Name.OperatorFunctionId.SymbolLocations[0]; 2044 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2045 = Name.EndLocation.getRawEncoding(); 2046 return NameInfo; 2047 2048 case UnqualifiedId::IK_LiteralOperatorId: 2049 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2050 Name.Identifier)); 2051 NameInfo.setLoc(Name.StartLocation); 2052 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2053 return NameInfo; 2054 2055 case UnqualifiedId::IK_ConversionFunctionId: { 2056 TypeSourceInfo *TInfo; 2057 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2058 if (Ty.isNull()) 2059 return DeclarationNameInfo(); 2060 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2061 Context.getCanonicalType(Ty))); 2062 NameInfo.setLoc(Name.StartLocation); 2063 NameInfo.setNamedTypeInfo(TInfo); 2064 return NameInfo; 2065 } 2066 2067 case UnqualifiedId::IK_ConstructorName: { 2068 TypeSourceInfo *TInfo; 2069 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2070 if (Ty.isNull()) 2071 return DeclarationNameInfo(); 2072 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2073 Context.getCanonicalType(Ty))); 2074 NameInfo.setLoc(Name.StartLocation); 2075 NameInfo.setNamedTypeInfo(TInfo); 2076 return NameInfo; 2077 } 2078 2079 case UnqualifiedId::IK_ConstructorTemplateId: { 2080 // In well-formed code, we can only have a constructor 2081 // template-id that refers to the current context, so go there 2082 // to find the actual type being constructed. 2083 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2084 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2085 return DeclarationNameInfo(); 2086 2087 // Determine the type of the class being constructed. 2088 QualType CurClassType = Context.getTypeDeclType(CurClass); 2089 2090 // FIXME: Check two things: that the template-id names the same type as 2091 // CurClassType, and that the template-id does not occur when the name 2092 // was qualified. 2093 2094 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2095 Context.getCanonicalType(CurClassType))); 2096 NameInfo.setLoc(Name.StartLocation); 2097 // FIXME: should we retrieve TypeSourceInfo? 2098 NameInfo.setNamedTypeInfo(0); 2099 return NameInfo; 2100 } 2101 2102 case UnqualifiedId::IK_DestructorName: { 2103 TypeSourceInfo *TInfo; 2104 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2105 if (Ty.isNull()) 2106 return DeclarationNameInfo(); 2107 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2108 Context.getCanonicalType(Ty))); 2109 NameInfo.setLoc(Name.StartLocation); 2110 NameInfo.setNamedTypeInfo(TInfo); 2111 return NameInfo; 2112 } 2113 2114 case UnqualifiedId::IK_TemplateId: { 2115 TemplateName TName = Name.TemplateId->Template.get(); 2116 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2117 return Context.getNameForTemplate(TName, TNameLoc); 2118 } 2119 2120 } // switch (Name.getKind()) 2121 2122 assert(false && "Unknown name kind"); 2123 return DeclarationNameInfo(); 2124} 2125 2126/// isNearlyMatchingFunction - Determine whether the C++ functions 2127/// Declaration and Definition are "nearly" matching. This heuristic 2128/// is used to improve diagnostics in the case where an out-of-line 2129/// function definition doesn't match any declaration within 2130/// the class or namespace. 2131static bool isNearlyMatchingFunction(ASTContext &Context, 2132 FunctionDecl *Declaration, 2133 FunctionDecl *Definition) { 2134 if (Declaration->param_size() != Definition->param_size()) 2135 return false; 2136 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2137 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2138 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2139 2140 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2141 DefParamTy.getNonReferenceType())) 2142 return false; 2143 } 2144 2145 return true; 2146} 2147 2148/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2149/// declarator needs to be rebuilt in the current instantiation. 2150/// Any bits of declarator which appear before the name are valid for 2151/// consideration here. That's specifically the type in the decl spec 2152/// and the base type in any member-pointer chunks. 2153static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2154 DeclarationName Name) { 2155 // The types we specifically need to rebuild are: 2156 // - typenames, typeofs, and decltypes 2157 // - types which will become injected class names 2158 // Of course, we also need to rebuild any type referencing such a 2159 // type. It's safest to just say "dependent", but we call out a 2160 // few cases here. 2161 2162 DeclSpec &DS = D.getMutableDeclSpec(); 2163 switch (DS.getTypeSpecType()) { 2164 case DeclSpec::TST_typename: 2165 case DeclSpec::TST_typeofType: 2166 case DeclSpec::TST_decltype: { 2167 // Grab the type from the parser. 2168 TypeSourceInfo *TSI = 0; 2169 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2170 if (T.isNull() || !T->isDependentType()) break; 2171 2172 // Make sure there's a type source info. This isn't really much 2173 // of a waste; most dependent types should have type source info 2174 // attached already. 2175 if (!TSI) 2176 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2177 2178 // Rebuild the type in the current instantiation. 2179 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2180 if (!TSI) return true; 2181 2182 // Store the new type back in the decl spec. 2183 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2184 DS.UpdateTypeRep(LocType); 2185 break; 2186 } 2187 2188 case DeclSpec::TST_typeofExpr: { 2189 Expr *E = DS.getRepAsExpr(); 2190 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2191 if (Result.isInvalid()) return true; 2192 DS.UpdateExprRep(Result.get()); 2193 break; 2194 } 2195 2196 default: 2197 // Nothing to do for these decl specs. 2198 break; 2199 } 2200 2201 // It doesn't matter what order we do this in. 2202 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2203 DeclaratorChunk &Chunk = D.getTypeObject(I); 2204 2205 // The only type information in the declarator which can come 2206 // before the declaration name is the base type of a member 2207 // pointer. 2208 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2209 continue; 2210 2211 // Rebuild the scope specifier in-place. 2212 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2213 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2214 return true; 2215 } 2216 2217 return false; 2218} 2219 2220Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2221 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2222} 2223 2224Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2225 MultiTemplateParamsArg TemplateParamLists, 2226 bool IsFunctionDefinition) { 2227 // TODO: consider using NameInfo for diagnostic. 2228 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2229 DeclarationName Name = NameInfo.getName(); 2230 2231 // All of these full declarators require an identifier. If it doesn't have 2232 // one, the ParsedFreeStandingDeclSpec action should be used. 2233 if (!Name) { 2234 if (!D.isInvalidType()) // Reject this if we think it is valid. 2235 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2236 diag::err_declarator_need_ident) 2237 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2238 return 0; 2239 } 2240 2241 // The scope passed in may not be a decl scope. Zip up the scope tree until 2242 // we find one that is. 2243 while ((S->getFlags() & Scope::DeclScope) == 0 || 2244 (S->getFlags() & Scope::TemplateParamScope) != 0) 2245 S = S->getParent(); 2246 2247 DeclContext *DC = CurContext; 2248 if (D.getCXXScopeSpec().isInvalid()) 2249 D.setInvalidType(); 2250 else if (D.getCXXScopeSpec().isSet()) { 2251 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2252 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2253 if (!DC) { 2254 // If we could not compute the declaration context, it's because the 2255 // declaration context is dependent but does not refer to a class, 2256 // class template, or class template partial specialization. Complain 2257 // and return early, to avoid the coming semantic disaster. 2258 Diag(D.getIdentifierLoc(), 2259 diag::err_template_qualified_declarator_no_match) 2260 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2261 << D.getCXXScopeSpec().getRange(); 2262 return 0; 2263 } 2264 2265 bool IsDependentContext = DC->isDependentContext(); 2266 2267 if (!IsDependentContext && 2268 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2269 return 0; 2270 2271 if (isa<CXXRecordDecl>(DC)) { 2272 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2273 Diag(D.getIdentifierLoc(), 2274 diag::err_member_def_undefined_record) 2275 << Name << DC << D.getCXXScopeSpec().getRange(); 2276 D.setInvalidType(); 2277 } else if (isa<CXXRecordDecl>(CurContext) && 2278 !D.getDeclSpec().isFriendSpecified()) { 2279 // The user provided a superfluous scope specifier inside a class 2280 // definition: 2281 // 2282 // class X { 2283 // void X::f(); 2284 // }; 2285 if (CurContext->Equals(DC)) 2286 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2287 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2288 else 2289 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2290 << Name << D.getCXXScopeSpec().getRange(); 2291 2292 // Pretend that this qualifier was not here. 2293 D.getCXXScopeSpec().clear(); 2294 } 2295 } 2296 2297 // Check whether we need to rebuild the type of the given 2298 // declaration in the current instantiation. 2299 if (EnteringContext && IsDependentContext && 2300 TemplateParamLists.size() != 0) { 2301 ContextRAII SavedContext(*this, DC); 2302 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2303 D.setInvalidType(); 2304 } 2305 } 2306 2307 // C++ [class.mem]p13: 2308 // If T is the name of a class, then each of the following shall have a 2309 // name different from T: 2310 // - every static data member of class T; 2311 // - every member function of class T 2312 // - every member of class T that is itself a type; 2313 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2314 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2315 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2316 << Name; 2317 2318 // If this is a typedef, we'll end up spewing multiple diagnostics. 2319 // Just return early; it's safer. 2320 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2321 return 0; 2322 } 2323 2324 NamedDecl *New; 2325 2326 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2327 QualType R = TInfo->getType(); 2328 2329 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2330 ForRedeclaration); 2331 2332 // See if this is a redefinition of a variable in the same scope. 2333 if (!D.getCXXScopeSpec().isSet()) { 2334 bool IsLinkageLookup = false; 2335 2336 // If the declaration we're planning to build will be a function 2337 // or object with linkage, then look for another declaration with 2338 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2339 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2340 /* Do nothing*/; 2341 else if (R->isFunctionType()) { 2342 if (CurContext->isFunctionOrMethod() || 2343 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2344 IsLinkageLookup = true; 2345 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2346 IsLinkageLookup = true; 2347 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2348 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2349 IsLinkageLookup = true; 2350 2351 if (IsLinkageLookup) 2352 Previous.clear(LookupRedeclarationWithLinkage); 2353 2354 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2355 } else { // Something like "int foo::x;" 2356 LookupQualifiedName(Previous, DC); 2357 2358 // Don't consider using declarations as previous declarations for 2359 // out-of-line members. 2360 RemoveUsingDecls(Previous); 2361 2362 // C++ 7.3.1.2p2: 2363 // Members (including explicit specializations of templates) of a named 2364 // namespace can also be defined outside that namespace by explicit 2365 // qualification of the name being defined, provided that the entity being 2366 // defined was already declared in the namespace and the definition appears 2367 // after the point of declaration in a namespace that encloses the 2368 // declarations namespace. 2369 // 2370 // Note that we only check the context at this point. We don't yet 2371 // have enough information to make sure that PrevDecl is actually 2372 // the declaration we want to match. For example, given: 2373 // 2374 // class X { 2375 // void f(); 2376 // void f(float); 2377 // }; 2378 // 2379 // void X::f(int) { } // ill-formed 2380 // 2381 // In this case, PrevDecl will point to the overload set 2382 // containing the two f's declared in X, but neither of them 2383 // matches. 2384 2385 // First check whether we named the global scope. 2386 if (isa<TranslationUnitDecl>(DC)) { 2387 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2388 << Name << D.getCXXScopeSpec().getRange(); 2389 } else { 2390 DeclContext *Cur = CurContext; 2391 while (isa<LinkageSpecDecl>(Cur)) 2392 Cur = Cur->getParent(); 2393 if (!Cur->Encloses(DC)) { 2394 // The qualifying scope doesn't enclose the original declaration. 2395 // Emit diagnostic based on current scope. 2396 SourceLocation L = D.getIdentifierLoc(); 2397 SourceRange R = D.getCXXScopeSpec().getRange(); 2398 if (isa<FunctionDecl>(Cur)) 2399 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2400 else 2401 Diag(L, diag::err_invalid_declarator_scope) 2402 << Name << cast<NamedDecl>(DC) << R; 2403 D.setInvalidType(); 2404 } 2405 } 2406 } 2407 2408 if (Previous.isSingleResult() && 2409 Previous.getFoundDecl()->isTemplateParameter()) { 2410 // Maybe we will complain about the shadowed template parameter. 2411 if (!D.isInvalidType()) 2412 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2413 Previous.getFoundDecl())) 2414 D.setInvalidType(); 2415 2416 // Just pretend that we didn't see the previous declaration. 2417 Previous.clear(); 2418 } 2419 2420 // In C++, the previous declaration we find might be a tag type 2421 // (class or enum). In this case, the new declaration will hide the 2422 // tag type. Note that this does does not apply if we're declaring a 2423 // typedef (C++ [dcl.typedef]p4). 2424 if (Previous.isSingleTagDecl() && 2425 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2426 Previous.clear(); 2427 2428 bool Redeclaration = false; 2429 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2430 if (TemplateParamLists.size()) { 2431 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2432 return 0; 2433 } 2434 2435 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2436 } else if (R->isFunctionType()) { 2437 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2438 move(TemplateParamLists), 2439 IsFunctionDefinition, Redeclaration); 2440 } else { 2441 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2442 move(TemplateParamLists), 2443 Redeclaration); 2444 } 2445 2446 if (New == 0) 2447 return 0; 2448 2449 // If this has an identifier and is not an invalid redeclaration or 2450 // function template specialization, add it to the scope stack. 2451 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2452 PushOnScopeChains(New, S); 2453 2454 return New; 2455} 2456 2457/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2458/// types into constant array types in certain situations which would otherwise 2459/// be errors (for GCC compatibility). 2460static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2461 ASTContext &Context, 2462 bool &SizeIsNegative, 2463 llvm::APSInt &Oversized) { 2464 // This method tries to turn a variable array into a constant 2465 // array even when the size isn't an ICE. This is necessary 2466 // for compatibility with code that depends on gcc's buggy 2467 // constant expression folding, like struct {char x[(int)(char*)2];} 2468 SizeIsNegative = false; 2469 Oversized = 0; 2470 2471 if (T->isDependentType()) 2472 return QualType(); 2473 2474 QualifierCollector Qs; 2475 const Type *Ty = Qs.strip(T); 2476 2477 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2478 QualType Pointee = PTy->getPointeeType(); 2479 QualType FixedType = 2480 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2481 Oversized); 2482 if (FixedType.isNull()) return FixedType; 2483 FixedType = Context.getPointerType(FixedType); 2484 return Qs.apply(FixedType); 2485 } 2486 2487 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2488 if (!VLATy) 2489 return QualType(); 2490 // FIXME: We should probably handle this case 2491 if (VLATy->getElementType()->isVariablyModifiedType()) 2492 return QualType(); 2493 2494 Expr::EvalResult EvalResult; 2495 if (!VLATy->getSizeExpr() || 2496 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2497 !EvalResult.Val.isInt()) 2498 return QualType(); 2499 2500 // Check whether the array size is negative. 2501 llvm::APSInt &Res = EvalResult.Val.getInt(); 2502 if (Res.isSigned() && Res.isNegative()) { 2503 SizeIsNegative = true; 2504 return QualType(); 2505 } 2506 2507 // Check whether the array is too large to be addressed. 2508 unsigned ActiveSizeBits 2509 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2510 Res); 2511 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2512 Oversized = Res; 2513 return QualType(); 2514 } 2515 2516 return Context.getConstantArrayType(VLATy->getElementType(), 2517 Res, ArrayType::Normal, 0); 2518} 2519 2520/// \brief Register the given locally-scoped external C declaration so 2521/// that it can be found later for redeclarations 2522void 2523Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2524 const LookupResult &Previous, 2525 Scope *S) { 2526 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2527 "Decl is not a locally-scoped decl!"); 2528 // Note that we have a locally-scoped external with this name. 2529 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2530 2531 if (!Previous.isSingleResult()) 2532 return; 2533 2534 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2535 2536 // If there was a previous declaration of this variable, it may be 2537 // in our identifier chain. Update the identifier chain with the new 2538 // declaration. 2539 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2540 // The previous declaration was found on the identifer resolver 2541 // chain, so remove it from its scope. 2542 while (S && !S->isDeclScope(PrevDecl)) 2543 S = S->getParent(); 2544 2545 if (S) 2546 S->RemoveDecl(PrevDecl); 2547 } 2548} 2549 2550/// \brief Diagnose function specifiers on a declaration of an identifier that 2551/// does not identify a function. 2552void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2553 // FIXME: We should probably indicate the identifier in question to avoid 2554 // confusion for constructs like "inline int a(), b;" 2555 if (D.getDeclSpec().isInlineSpecified()) 2556 Diag(D.getDeclSpec().getInlineSpecLoc(), 2557 diag::err_inline_non_function); 2558 2559 if (D.getDeclSpec().isVirtualSpecified()) 2560 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2561 diag::err_virtual_non_function); 2562 2563 if (D.getDeclSpec().isExplicitSpecified()) 2564 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2565 diag::err_explicit_non_function); 2566} 2567 2568NamedDecl* 2569Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2570 QualType R, TypeSourceInfo *TInfo, 2571 LookupResult &Previous, bool &Redeclaration) { 2572 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2573 if (D.getCXXScopeSpec().isSet()) { 2574 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2575 << D.getCXXScopeSpec().getRange(); 2576 D.setInvalidType(); 2577 // Pretend we didn't see the scope specifier. 2578 DC = CurContext; 2579 Previous.clear(); 2580 } 2581 2582 if (getLangOptions().CPlusPlus) { 2583 // Check that there are no default arguments (C++ only). 2584 CheckExtraCXXDefaultArguments(D); 2585 } 2586 2587 DiagnoseFunctionSpecifiers(D); 2588 2589 if (D.getDeclSpec().isThreadSpecified()) 2590 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2591 2592 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2593 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2594 << D.getName().getSourceRange(); 2595 return 0; 2596 } 2597 2598 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2599 if (!NewTD) return 0; 2600 2601 // Handle attributes prior to checking for duplicates in MergeVarDecl 2602 ProcessDeclAttributes(S, NewTD, D); 2603 2604 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2605 // then it shall have block scope. 2606 // Note that variably modified types must be fixed before merging the decl so 2607 // that redeclarations will match. 2608 QualType T = NewTD->getUnderlyingType(); 2609 if (T->isVariablyModifiedType()) { 2610 getCurFunction()->setHasBranchProtectedScope(); 2611 2612 if (S->getFnParent() == 0) { 2613 bool SizeIsNegative; 2614 llvm::APSInt Oversized; 2615 QualType FixedTy = 2616 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2617 Oversized); 2618 if (!FixedTy.isNull()) { 2619 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2620 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2621 } else { 2622 if (SizeIsNegative) 2623 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2624 else if (T->isVariableArrayType()) 2625 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2626 else if (Oversized.getBoolValue()) 2627 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2628 << Oversized.toString(10); 2629 else 2630 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2631 NewTD->setInvalidDecl(); 2632 } 2633 } 2634 } 2635 2636 // Merge the decl with the existing one if appropriate. If the decl is 2637 // in an outer scope, it isn't the same thing. 2638 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2639 if (!Previous.empty()) { 2640 Redeclaration = true; 2641 MergeTypeDefDecl(NewTD, Previous); 2642 } 2643 2644 // If this is the C FILE type, notify the AST context. 2645 if (IdentifierInfo *II = NewTD->getIdentifier()) 2646 if (!NewTD->isInvalidDecl() && 2647 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2648 if (II->isStr("FILE")) 2649 Context.setFILEDecl(NewTD); 2650 else if (II->isStr("jmp_buf")) 2651 Context.setjmp_bufDecl(NewTD); 2652 else if (II->isStr("sigjmp_buf")) 2653 Context.setsigjmp_bufDecl(NewTD); 2654 else if (II->isStr("__builtin_va_list")) 2655 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2656 } 2657 2658 return NewTD; 2659} 2660 2661/// \brief Determines whether the given declaration is an out-of-scope 2662/// previous declaration. 2663/// 2664/// This routine should be invoked when name lookup has found a 2665/// previous declaration (PrevDecl) that is not in the scope where a 2666/// new declaration by the same name is being introduced. If the new 2667/// declaration occurs in a local scope, previous declarations with 2668/// linkage may still be considered previous declarations (C99 2669/// 6.2.2p4-5, C++ [basic.link]p6). 2670/// 2671/// \param PrevDecl the previous declaration found by name 2672/// lookup 2673/// 2674/// \param DC the context in which the new declaration is being 2675/// declared. 2676/// 2677/// \returns true if PrevDecl is an out-of-scope previous declaration 2678/// for a new delcaration with the same name. 2679static bool 2680isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2681 ASTContext &Context) { 2682 if (!PrevDecl) 2683 return false; 2684 2685 if (!PrevDecl->hasLinkage()) 2686 return false; 2687 2688 if (Context.getLangOptions().CPlusPlus) { 2689 // C++ [basic.link]p6: 2690 // If there is a visible declaration of an entity with linkage 2691 // having the same name and type, ignoring entities declared 2692 // outside the innermost enclosing namespace scope, the block 2693 // scope declaration declares that same entity and receives the 2694 // linkage of the previous declaration. 2695 DeclContext *OuterContext = DC->getRedeclContext(); 2696 if (!OuterContext->isFunctionOrMethod()) 2697 // This rule only applies to block-scope declarations. 2698 return false; 2699 2700 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2701 if (PrevOuterContext->isRecord()) 2702 // We found a member function: ignore it. 2703 return false; 2704 2705 // Find the innermost enclosing namespace for the new and 2706 // previous declarations. 2707 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2708 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2709 2710 // The previous declaration is in a different namespace, so it 2711 // isn't the same function. 2712 if (!OuterContext->Equals(PrevOuterContext)) 2713 return false; 2714 } 2715 2716 return true; 2717} 2718 2719static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2720 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2721 if (!SS.isSet()) return; 2722 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2723 SS.getRange()); 2724} 2725 2726NamedDecl* 2727Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 2728 QualType R, TypeSourceInfo *TInfo, 2729 LookupResult &Previous, 2730 MultiTemplateParamsArg TemplateParamLists, 2731 bool &Redeclaration) { 2732 DeclarationName Name = GetNameForDeclarator(D).getName(); 2733 2734 // Check that there are no default arguments (C++ only). 2735 if (getLangOptions().CPlusPlus) 2736 CheckExtraCXXDefaultArguments(D); 2737 2738 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2739 assert(SCSpec != DeclSpec::SCS_typedef && 2740 "Parser allowed 'typedef' as storage class VarDecl."); 2741 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2742 if (SCSpec == DeclSpec::SCS_mutable) { 2743 // mutable can only appear on non-static class members, so it's always 2744 // an error here 2745 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2746 D.setInvalidType(); 2747 SC = SC_None; 2748 } 2749 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2750 VarDecl::StorageClass SCAsWritten 2751 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2752 2753 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2754 if (!II) { 2755 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2756 << Name.getAsString(); 2757 return 0; 2758 } 2759 2760 DiagnoseFunctionSpecifiers(D); 2761 2762 if (!DC->isRecord() && S->getFnParent() == 0) { 2763 // C99 6.9p2: The storage-class specifiers auto and register shall not 2764 // appear in the declaration specifiers in an external declaration. 2765 if (SC == SC_Auto || SC == SC_Register) { 2766 2767 // If this is a register variable with an asm label specified, then this 2768 // is a GNU extension. 2769 if (SC == SC_Register && D.getAsmLabel()) 2770 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2771 else 2772 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2773 D.setInvalidType(); 2774 } 2775 } 2776 if (DC->isRecord() && !CurContext->isRecord()) { 2777 // This is an out-of-line definition of a static data member. 2778 if (SC == SC_Static) { 2779 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2780 diag::err_static_out_of_line) 2781 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2782 } else if (SC == SC_None) 2783 SC = SC_Static; 2784 } 2785 if (SC == SC_Static) { 2786 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2787 if (RD->isLocalClass()) 2788 Diag(D.getIdentifierLoc(), 2789 diag::err_static_data_member_not_allowed_in_local_class) 2790 << Name << RD->getDeclName(); 2791 } 2792 } 2793 2794 // Match up the template parameter lists with the scope specifier, then 2795 // determine whether we have a template or a template specialization. 2796 bool isExplicitSpecialization = false; 2797 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2798 bool Invalid = false; 2799 if (TemplateParameterList *TemplateParams 2800 = MatchTemplateParametersToScopeSpecifier( 2801 D.getDeclSpec().getSourceRange().getBegin(), 2802 D.getCXXScopeSpec(), 2803 TemplateParamLists.get(), 2804 TemplateParamLists.size(), 2805 /*never a friend*/ false, 2806 isExplicitSpecialization, 2807 Invalid)) { 2808 // All but one template parameter lists have been matching. 2809 --NumMatchedTemplateParamLists; 2810 2811 if (TemplateParams->size() > 0) { 2812 // There is no such thing as a variable template. 2813 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2814 << II 2815 << SourceRange(TemplateParams->getTemplateLoc(), 2816 TemplateParams->getRAngleLoc()); 2817 return 0; 2818 } else { 2819 // There is an extraneous 'template<>' for this variable. Complain 2820 // about it, but allow the declaration of the variable. 2821 Diag(TemplateParams->getTemplateLoc(), 2822 diag::err_template_variable_noparams) 2823 << II 2824 << SourceRange(TemplateParams->getTemplateLoc(), 2825 TemplateParams->getRAngleLoc()); 2826 2827 isExplicitSpecialization = true; 2828 } 2829 } 2830 2831 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2832 II, R, TInfo, SC, SCAsWritten); 2833 2834 if (D.isInvalidType() || Invalid) 2835 NewVD->setInvalidDecl(); 2836 2837 SetNestedNameSpecifier(NewVD, D); 2838 2839 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2840 NewVD->setTemplateParameterListsInfo(Context, 2841 NumMatchedTemplateParamLists, 2842 TemplateParamLists.release()); 2843 } 2844 2845 if (D.getDeclSpec().isThreadSpecified()) { 2846 if (NewVD->hasLocalStorage()) 2847 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2848 else if (!Context.Target.isTLSSupported()) 2849 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2850 else 2851 NewVD->setThreadSpecified(true); 2852 } 2853 2854 // Set the lexical context. If the declarator has a C++ scope specifier, the 2855 // lexical context will be different from the semantic context. 2856 NewVD->setLexicalDeclContext(CurContext); 2857 2858 // Handle attributes prior to checking for duplicates in MergeVarDecl 2859 ProcessDeclAttributes(S, NewVD, D); 2860 2861 // Handle GNU asm-label extension (encoded as an attribute). 2862 if (Expr *E = (Expr*)D.getAsmLabel()) { 2863 // The parser guarantees this is a string. 2864 StringLiteral *SE = cast<StringLiteral>(E); 2865 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2866 Context, SE->getString())); 2867 } 2868 2869 // Diagnose shadowed variables before filtering for scope. 2870 if (!D.getCXXScopeSpec().isSet()) 2871 CheckShadow(S, NewVD, Previous); 2872 2873 // Don't consider existing declarations that are in a different 2874 // scope and are out-of-semantic-context declarations (if the new 2875 // declaration has linkage). 2876 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2877 2878 // Merge the decl with the existing one if appropriate. 2879 if (!Previous.empty()) { 2880 if (Previous.isSingleResult() && 2881 isa<FieldDecl>(Previous.getFoundDecl()) && 2882 D.getCXXScopeSpec().isSet()) { 2883 // The user tried to define a non-static data member 2884 // out-of-line (C++ [dcl.meaning]p1). 2885 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2886 << D.getCXXScopeSpec().getRange(); 2887 Previous.clear(); 2888 NewVD->setInvalidDecl(); 2889 } 2890 } else if (D.getCXXScopeSpec().isSet()) { 2891 // No previous declaration in the qualifying scope. 2892 Diag(D.getIdentifierLoc(), diag::err_no_member) 2893 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2894 << D.getCXXScopeSpec().getRange(); 2895 NewVD->setInvalidDecl(); 2896 } 2897 2898 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2899 2900 // This is an explicit specialization of a static data member. Check it. 2901 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2902 CheckMemberSpecialization(NewVD, Previous)) 2903 NewVD->setInvalidDecl(); 2904 2905 // attributes declared post-definition are currently ignored 2906 // FIXME: This should be handled in attribute merging, not 2907 // here. 2908 if (Previous.isSingleResult()) { 2909 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2910 if (Def && (Def = Def->getDefinition()) && 2911 Def != NewVD && D.hasAttributes()) { 2912 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2913 Diag(Def->getLocation(), diag::note_previous_definition); 2914 } 2915 } 2916 2917 // If this is a locally-scoped extern C variable, update the map of 2918 // such variables. 2919 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2920 !NewVD->isInvalidDecl()) 2921 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2922 2923 // If there's a #pragma GCC visibility in scope, and this isn't a class 2924 // member, set the visibility of this variable. 2925 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2926 AddPushedVisibilityAttribute(NewVD); 2927 2928 MarkUnusedFileScopedDecl(NewVD); 2929 2930 return NewVD; 2931} 2932 2933/// \brief Diagnose variable or built-in function shadowing. Implements 2934/// -Wshadow. 2935/// 2936/// This method is called whenever a VarDecl is added to a "useful" 2937/// scope. 2938/// 2939/// \param S the scope in which the shadowing name is being declared 2940/// \param R the lookup of the name 2941/// 2942void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2943 // Return if warning is ignored. 2944 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2945 return; 2946 2947 // Don't diagnose declarations at file scope. The scope might not 2948 // have a DeclContext if (e.g.) we're parsing a function prototype. 2949 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2950 if (NewDC && NewDC->isFileContext()) 2951 return; 2952 2953 // Only diagnose if we're shadowing an unambiguous field or variable. 2954 if (R.getResultKind() != LookupResult::Found) 2955 return; 2956 2957 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2958 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2959 return; 2960 2961 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2962 2963 // Only warn about certain kinds of shadowing for class members. 2964 if (NewDC && NewDC->isRecord()) { 2965 // In particular, don't warn about shadowing non-class members. 2966 if (!OldDC->isRecord()) 2967 return; 2968 2969 // TODO: should we warn about static data members shadowing 2970 // static data members from base classes? 2971 2972 // TODO: don't diagnose for inaccessible shadowed members. 2973 // This is hard to do perfectly because we might friend the 2974 // shadowing context, but that's just a false negative. 2975 } 2976 2977 // Determine what kind of declaration we're shadowing. 2978 unsigned Kind; 2979 if (isa<RecordDecl>(OldDC)) { 2980 if (isa<FieldDecl>(ShadowedDecl)) 2981 Kind = 3; // field 2982 else 2983 Kind = 2; // static data member 2984 } else if (OldDC->isFileContext()) 2985 Kind = 1; // global 2986 else 2987 Kind = 0; // local 2988 2989 DeclarationName Name = R.getLookupName(); 2990 2991 // Emit warning and note. 2992 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2993 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2994} 2995 2996/// \brief Check -Wshadow without the advantage of a previous lookup. 2997void Sema::CheckShadow(Scope *S, VarDecl *D) { 2998 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2999 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3000 LookupName(R, S); 3001 CheckShadow(S, D, R); 3002} 3003 3004/// \brief Perform semantic checking on a newly-created variable 3005/// declaration. 3006/// 3007/// This routine performs all of the type-checking required for a 3008/// variable declaration once it has been built. It is used both to 3009/// check variables after they have been parsed and their declarators 3010/// have been translated into a declaration, and to check variables 3011/// that have been instantiated from a template. 3012/// 3013/// Sets NewVD->isInvalidDecl() if an error was encountered. 3014void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3015 LookupResult &Previous, 3016 bool &Redeclaration) { 3017 // If the decl is already known invalid, don't check it. 3018 if (NewVD->isInvalidDecl()) 3019 return; 3020 3021 QualType T = NewVD->getType(); 3022 3023 if (T->isObjCObjectType()) { 3024 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3025 return NewVD->setInvalidDecl(); 3026 } 3027 3028 // Emit an error if an address space was applied to decl with local storage. 3029 // This includes arrays of objects with address space qualifiers, but not 3030 // automatic variables that point to other address spaces. 3031 // ISO/IEC TR 18037 S5.1.2 3032 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3033 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3034 return NewVD->setInvalidDecl(); 3035 } 3036 3037 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3038 && !NewVD->hasAttr<BlocksAttr>()) 3039 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3040 3041 bool isVM = T->isVariablyModifiedType(); 3042 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3043 NewVD->hasAttr<BlocksAttr>()) 3044 getCurFunction()->setHasBranchProtectedScope(); 3045 3046 if ((isVM && NewVD->hasLinkage()) || 3047 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3048 bool SizeIsNegative; 3049 llvm::APSInt Oversized; 3050 QualType FixedTy = 3051 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3052 Oversized); 3053 3054 if (FixedTy.isNull() && T->isVariableArrayType()) { 3055 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3056 // FIXME: This won't give the correct result for 3057 // int a[10][n]; 3058 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3059 3060 if (NewVD->isFileVarDecl()) 3061 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3062 << SizeRange; 3063 else if (NewVD->getStorageClass() == SC_Static) 3064 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3065 << SizeRange; 3066 else 3067 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3068 << SizeRange; 3069 return NewVD->setInvalidDecl(); 3070 } 3071 3072 if (FixedTy.isNull()) { 3073 if (NewVD->isFileVarDecl()) 3074 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3075 else 3076 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3077 return NewVD->setInvalidDecl(); 3078 } 3079 3080 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3081 NewVD->setType(FixedTy); 3082 } 3083 3084 if (Previous.empty() && NewVD->isExternC()) { 3085 // Since we did not find anything by this name and we're declaring 3086 // an extern "C" variable, look for a non-visible extern "C" 3087 // declaration with the same name. 3088 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3089 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3090 if (Pos != LocallyScopedExternalDecls.end()) 3091 Previous.addDecl(Pos->second); 3092 } 3093 3094 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3095 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3096 << T; 3097 return NewVD->setInvalidDecl(); 3098 } 3099 3100 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3101 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3102 return NewVD->setInvalidDecl(); 3103 } 3104 3105 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3106 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3107 return NewVD->setInvalidDecl(); 3108 } 3109 3110 // Function pointers and references cannot have qualified function type, only 3111 // function pointer-to-members can do that. 3112 QualType Pointee; 3113 unsigned PtrOrRef = 0; 3114 if (const PointerType *Ptr = T->getAs<PointerType>()) 3115 Pointee = Ptr->getPointeeType(); 3116 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3117 Pointee = Ref->getPointeeType(); 3118 PtrOrRef = 1; 3119 } 3120 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3121 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3122 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3123 << PtrOrRef; 3124 return NewVD->setInvalidDecl(); 3125 } 3126 3127 if (!Previous.empty()) { 3128 Redeclaration = true; 3129 MergeVarDecl(NewVD, Previous); 3130 } 3131} 3132 3133/// \brief Data used with FindOverriddenMethod 3134struct FindOverriddenMethodData { 3135 Sema *S; 3136 CXXMethodDecl *Method; 3137}; 3138 3139/// \brief Member lookup function that determines whether a given C++ 3140/// method overrides a method in a base class, to be used with 3141/// CXXRecordDecl::lookupInBases(). 3142static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3143 CXXBasePath &Path, 3144 void *UserData) { 3145 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3146 3147 FindOverriddenMethodData *Data 3148 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3149 3150 DeclarationName Name = Data->Method->getDeclName(); 3151 3152 // FIXME: Do we care about other names here too? 3153 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3154 // We really want to find the base class destructor here. 3155 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3156 CanQualType CT = Data->S->Context.getCanonicalType(T); 3157 3158 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3159 } 3160 3161 for (Path.Decls = BaseRecord->lookup(Name); 3162 Path.Decls.first != Path.Decls.second; 3163 ++Path.Decls.first) { 3164 NamedDecl *D = *Path.Decls.first; 3165 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3166 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3167 return true; 3168 } 3169 } 3170 3171 return false; 3172} 3173 3174/// AddOverriddenMethods - See if a method overrides any in the base classes, 3175/// and if so, check that it's a valid override and remember it. 3176bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3177 // Look for virtual methods in base classes that this method might override. 3178 CXXBasePaths Paths; 3179 FindOverriddenMethodData Data; 3180 Data.Method = MD; 3181 Data.S = this; 3182 bool AddedAny = false; 3183 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3184 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3185 E = Paths.found_decls_end(); I != E; ++I) { 3186 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3187 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3188 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3189 !CheckOverridingFunctionAttributes(MD, OldMD)) { 3190 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3191 AddedAny = true; 3192 } 3193 } 3194 } 3195 } 3196 3197 return AddedAny; 3198} 3199 3200static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3201 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3202 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3203 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3204 assert(!Prev.isAmbiguous() && 3205 "Cannot have an ambiguity in previous-declaration lookup"); 3206 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3207 Func != FuncEnd; ++Func) { 3208 if (isa<FunctionDecl>(*Func) && 3209 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3210 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3211 } 3212} 3213 3214/// CheckClassMemberNameAttributes - Check for class member name checking 3215/// attributes according to [dcl.attr.override] 3216static void 3217CheckClassMemberNameAttributes(Sema& SemaRef, const FunctionDecl *FD) { 3218 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); 3219 if (!MD || !MD->isVirtual()) 3220 return; 3221 3222 bool HasOverrideAttr = MD->hasAttr<OverrideAttr>(); 3223 bool HasOverriddenMethods = 3224 MD->begin_overridden_methods() != MD->end_overridden_methods(); 3225 3226 /// C++ [dcl.attr.override]p2: 3227 /// If a virtual member function f is marked override and does not override 3228 /// a member function of a base class the program is ill-formed. 3229 if (HasOverrideAttr && !HasOverriddenMethods) { 3230 SemaRef.Diag(MD->getLocation(), diag::err_override_function_not_overriding) 3231 << MD->getDeclName(); 3232 return; 3233 } 3234 3235 if (!MD->getParent()->hasAttr<BaseCheckAttr>()) 3236 return; 3237 3238 /// C++ [dcl.attr.override]p6: 3239 /// In a class definition marked base_check, if a virtual member function 3240 /// that is neither implicitly-declared nor a destructor overrides a 3241 /// member function of a base class and it is not marked override, the 3242 /// program is ill-formed. 3243 if (HasOverriddenMethods && !HasOverrideAttr && !MD->isImplicit() && 3244 !isa<CXXDestructorDecl>(MD)) { 3245 llvm::SmallVector<const CXXMethodDecl*, 4> 3246 OverriddenMethods(MD->begin_overridden_methods(), 3247 MD->end_overridden_methods()); 3248 3249 SemaRef.Diag(MD->getLocation(), 3250 diag::err_function_overriding_without_override) 3251 << MD->getDeclName() << (unsigned)OverriddenMethods.size(); 3252 3253 for (unsigned I = 0; I != OverriddenMethods.size(); ++I) 3254 SemaRef.Diag(OverriddenMethods[I]->getLocation(), 3255 diag::note_overridden_virtual_function); 3256 } 3257} 3258 3259NamedDecl* 3260Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3261 QualType R, TypeSourceInfo *TInfo, 3262 LookupResult &Previous, 3263 MultiTemplateParamsArg TemplateParamLists, 3264 bool IsFunctionDefinition, bool &Redeclaration) { 3265 assert(R.getTypePtr()->isFunctionType()); 3266 3267 // TODO: consider using NameInfo for diagnostic. 3268 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3269 DeclarationName Name = NameInfo.getName(); 3270 FunctionDecl::StorageClass SC = SC_None; 3271 switch (D.getDeclSpec().getStorageClassSpec()) { 3272 default: assert(0 && "Unknown storage class!"); 3273 case DeclSpec::SCS_auto: 3274 case DeclSpec::SCS_register: 3275 case DeclSpec::SCS_mutable: 3276 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3277 diag::err_typecheck_sclass_func); 3278 D.setInvalidType(); 3279 break; 3280 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3281 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3282 case DeclSpec::SCS_static: { 3283 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3284 // C99 6.7.1p5: 3285 // The declaration of an identifier for a function that has 3286 // block scope shall have no explicit storage-class specifier 3287 // other than extern 3288 // See also (C++ [dcl.stc]p4). 3289 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3290 diag::err_static_block_func); 3291 SC = SC_None; 3292 } else 3293 SC = SC_Static; 3294 break; 3295 } 3296 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3297 } 3298 3299 if (D.getDeclSpec().isThreadSpecified()) 3300 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3301 3302 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3303 bool isInline = D.getDeclSpec().isInlineSpecified(); 3304 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3305 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3306 3307 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3308 FunctionDecl::StorageClass SCAsWritten 3309 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3310 3311 // Check that the return type is not an abstract class type. 3312 // For record types, this is done by the AbstractClassUsageDiagnoser once 3313 // the class has been completely parsed. 3314 if (!DC->isRecord() && 3315 RequireNonAbstractType(D.getIdentifierLoc(), 3316 R->getAs<FunctionType>()->getResultType(), 3317 diag::err_abstract_type_in_decl, 3318 AbstractReturnType)) 3319 D.setInvalidType(); 3320 3321 // Do not allow returning a objc interface by-value. 3322 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3323 Diag(D.getIdentifierLoc(), 3324 diag::err_object_cannot_be_passed_returned_by_value) << 0 3325 << R->getAs<FunctionType>()->getResultType(); 3326 D.setInvalidType(); 3327 } 3328 3329 bool isVirtualOkay = false; 3330 FunctionDecl *NewFD; 3331 3332 if (isFriend) { 3333 // C++ [class.friend]p5 3334 // A function can be defined in a friend declaration of a 3335 // class . . . . Such a function is implicitly inline. 3336 isInline |= IsFunctionDefinition; 3337 } 3338 3339 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3340 // This is a C++ constructor declaration. 3341 assert(DC->isRecord() && 3342 "Constructors can only be declared in a member context"); 3343 3344 R = CheckConstructorDeclarator(D, R, SC); 3345 3346 // Create the new declaration 3347 NewFD = CXXConstructorDecl::Create(Context, 3348 cast<CXXRecordDecl>(DC), 3349 NameInfo, R, TInfo, 3350 isExplicit, isInline, 3351 /*isImplicitlyDeclared=*/false); 3352 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3353 // This is a C++ destructor declaration. 3354 if (DC->isRecord()) { 3355 R = CheckDestructorDeclarator(D, R, SC); 3356 3357 NewFD = CXXDestructorDecl::Create(Context, 3358 cast<CXXRecordDecl>(DC), 3359 NameInfo, R, TInfo, 3360 isInline, 3361 /*isImplicitlyDeclared=*/false); 3362 isVirtualOkay = true; 3363 } else { 3364 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3365 3366 // Create a FunctionDecl to satisfy the function definition parsing 3367 // code path. 3368 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3369 Name, R, TInfo, SC, SCAsWritten, isInline, 3370 /*hasPrototype=*/true); 3371 D.setInvalidType(); 3372 } 3373 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3374 if (!DC->isRecord()) { 3375 Diag(D.getIdentifierLoc(), 3376 diag::err_conv_function_not_member); 3377 return 0; 3378 } 3379 3380 CheckConversionDeclarator(D, R, SC); 3381 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3382 NameInfo, R, TInfo, 3383 isInline, isExplicit); 3384 3385 isVirtualOkay = true; 3386 } else if (DC->isRecord()) { 3387 // If the of the function is the same as the name of the record, then this 3388 // must be an invalid constructor that has a return type. 3389 // (The parser checks for a return type and makes the declarator a 3390 // constructor if it has no return type). 3391 // must have an invalid constructor that has a return type 3392 if (Name.getAsIdentifierInfo() && 3393 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3394 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3395 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3396 << SourceRange(D.getIdentifierLoc()); 3397 return 0; 3398 } 3399 3400 bool isStatic = SC == SC_Static; 3401 3402 // [class.free]p1: 3403 // Any allocation function for a class T is a static member 3404 // (even if not explicitly declared static). 3405 if (Name.getCXXOverloadedOperator() == OO_New || 3406 Name.getCXXOverloadedOperator() == OO_Array_New) 3407 isStatic = true; 3408 3409 // [class.free]p6 Any deallocation function for a class X is a static member 3410 // (even if not explicitly declared static). 3411 if (Name.getCXXOverloadedOperator() == OO_Delete || 3412 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3413 isStatic = true; 3414 3415 // This is a C++ method declaration. 3416 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3417 NameInfo, R, TInfo, 3418 isStatic, SCAsWritten, isInline); 3419 3420 isVirtualOkay = !isStatic; 3421 } else { 3422 // Determine whether the function was written with a 3423 // prototype. This true when: 3424 // - we're in C++ (where every function has a prototype), 3425 // - there is a prototype in the declarator, or 3426 // - the type R of the function is some kind of typedef or other reference 3427 // to a type name (which eventually refers to a function type). 3428 bool HasPrototype = 3429 getLangOptions().CPlusPlus || 3430 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3431 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3432 3433 NewFD = FunctionDecl::Create(Context, DC, 3434 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3435 HasPrototype); 3436 } 3437 3438 if (D.isInvalidType()) 3439 NewFD->setInvalidDecl(); 3440 3441 SetNestedNameSpecifier(NewFD, D); 3442 3443 // Set the lexical context. If the declarator has a C++ 3444 // scope specifier, or is the object of a friend declaration, the 3445 // lexical context will be different from the semantic context. 3446 NewFD->setLexicalDeclContext(CurContext); 3447 3448 // Match up the template parameter lists with the scope specifier, then 3449 // determine whether we have a template or a template specialization. 3450 FunctionTemplateDecl *FunctionTemplate = 0; 3451 bool isExplicitSpecialization = false; 3452 bool isFunctionTemplateSpecialization = false; 3453 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3454 bool Invalid = false; 3455 if (TemplateParameterList *TemplateParams 3456 = MatchTemplateParametersToScopeSpecifier( 3457 D.getDeclSpec().getSourceRange().getBegin(), 3458 D.getCXXScopeSpec(), 3459 TemplateParamLists.get(), 3460 TemplateParamLists.size(), 3461 isFriend, 3462 isExplicitSpecialization, 3463 Invalid)) { 3464 // All but one template parameter lists have been matching. 3465 --NumMatchedTemplateParamLists; 3466 3467 if (TemplateParams->size() > 0) { 3468 // This is a function template 3469 3470 // Check that we can declare a template here. 3471 if (CheckTemplateDeclScope(S, TemplateParams)) 3472 return 0; 3473 3474 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3475 NewFD->getLocation(), 3476 Name, TemplateParams, 3477 NewFD); 3478 FunctionTemplate->setLexicalDeclContext(CurContext); 3479 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3480 } else { 3481 // This is a function template specialization. 3482 isFunctionTemplateSpecialization = true; 3483 3484 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3485 if (isFriend && isFunctionTemplateSpecialization) { 3486 // We want to remove the "template<>", found here. 3487 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3488 3489 // If we remove the template<> and the name is not a 3490 // template-id, we're actually silently creating a problem: 3491 // the friend declaration will refer to an untemplated decl, 3492 // and clearly the user wants a template specialization. So 3493 // we need to insert '<>' after the name. 3494 SourceLocation InsertLoc; 3495 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3496 InsertLoc = D.getName().getSourceRange().getEnd(); 3497 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3498 } 3499 3500 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3501 << Name << RemoveRange 3502 << FixItHint::CreateRemoval(RemoveRange) 3503 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3504 } 3505 } 3506 } 3507 3508 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3509 NewFD->setTemplateParameterListsInfo(Context, 3510 NumMatchedTemplateParamLists, 3511 TemplateParamLists.release()); 3512 } 3513 3514 if (Invalid) { 3515 NewFD->setInvalidDecl(); 3516 if (FunctionTemplate) 3517 FunctionTemplate->setInvalidDecl(); 3518 } 3519 3520 // C++ [dcl.fct.spec]p5: 3521 // The virtual specifier shall only be used in declarations of 3522 // nonstatic class member functions that appear within a 3523 // member-specification of a class declaration; see 10.3. 3524 // 3525 if (isVirtual && !NewFD->isInvalidDecl()) { 3526 if (!isVirtualOkay) { 3527 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3528 diag::err_virtual_non_function); 3529 } else if (!CurContext->isRecord()) { 3530 // 'virtual' was specified outside of the class. 3531 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3532 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3533 } else { 3534 // Okay: Add virtual to the method. 3535 NewFD->setVirtualAsWritten(true); 3536 } 3537 } 3538 3539 // C++ [dcl.fct.spec]p3: 3540 // The inline specifier shall not appear on a block scope function declaration. 3541 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3542 if (CurContext->isFunctionOrMethod()) { 3543 // 'inline' is not allowed on block scope function declaration. 3544 Diag(D.getDeclSpec().getInlineSpecLoc(), 3545 diag::err_inline_declaration_block_scope) << Name 3546 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3547 } 3548 } 3549 3550 // C++ [dcl.fct.spec]p6: 3551 // The explicit specifier shall be used only in the declaration of a 3552 // constructor or conversion function within its class definition; see 12.3.1 3553 // and 12.3.2. 3554 if (isExplicit && !NewFD->isInvalidDecl()) { 3555 if (!CurContext->isRecord()) { 3556 // 'explicit' was specified outside of the class. 3557 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3558 diag::err_explicit_out_of_class) 3559 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3560 } else if (!isa<CXXConstructorDecl>(NewFD) && 3561 !isa<CXXConversionDecl>(NewFD)) { 3562 // 'explicit' was specified on a function that wasn't a constructor 3563 // or conversion function. 3564 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3565 diag::err_explicit_non_ctor_or_conv_function) 3566 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3567 } 3568 } 3569 3570 // Filter out previous declarations that don't match the scope. 3571 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3572 3573 if (isFriend) { 3574 // For now, claim that the objects have no previous declaration. 3575 if (FunctionTemplate) { 3576 FunctionTemplate->setObjectOfFriendDecl(false); 3577 FunctionTemplate->setAccess(AS_public); 3578 } 3579 NewFD->setObjectOfFriendDecl(false); 3580 NewFD->setAccess(AS_public); 3581 } 3582 3583 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3584 !CurContext->isRecord()) { 3585 // C++ [class.static]p1: 3586 // A data or function member of a class may be declared static 3587 // in a class definition, in which case it is a static member of 3588 // the class. 3589 3590 // Complain about the 'static' specifier if it's on an out-of-line 3591 // member function definition. 3592 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3593 diag::err_static_out_of_line) 3594 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3595 } 3596 3597 // Handle GNU asm-label extension (encoded as an attribute). 3598 if (Expr *E = (Expr*) D.getAsmLabel()) { 3599 // The parser guarantees this is a string. 3600 StringLiteral *SE = cast<StringLiteral>(E); 3601 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3602 SE->getString())); 3603 } 3604 3605 // Copy the parameter declarations from the declarator D to the function 3606 // declaration NewFD, if they are available. First scavenge them into Params. 3607 llvm::SmallVector<ParmVarDecl*, 16> Params; 3608 if (D.getNumTypeObjects() > 0) { 3609 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3610 3611 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3612 // function that takes no arguments, not a function that takes a 3613 // single void argument. 3614 // We let through "const void" here because Sema::GetTypeForDeclarator 3615 // already checks for that case. 3616 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3617 FTI.ArgInfo[0].Param && 3618 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3619 // Empty arg list, don't push any params. 3620 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3621 3622 // In C++, the empty parameter-type-list must be spelled "void"; a 3623 // typedef of void is not permitted. 3624 if (getLangOptions().CPlusPlus && 3625 Param->getType().getUnqualifiedType() != Context.VoidTy) 3626 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3627 // FIXME: Leaks decl? 3628 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3629 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3630 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3631 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3632 Param->setDeclContext(NewFD); 3633 Params.push_back(Param); 3634 3635 if (Param->isInvalidDecl()) 3636 NewFD->setInvalidDecl(); 3637 } 3638 } 3639 3640 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3641 // When we're declaring a function with a typedef, typeof, etc as in the 3642 // following example, we'll need to synthesize (unnamed) 3643 // parameters for use in the declaration. 3644 // 3645 // @code 3646 // typedef void fn(int); 3647 // fn f; 3648 // @endcode 3649 3650 // Synthesize a parameter for each argument type. 3651 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3652 AE = FT->arg_type_end(); AI != AE; ++AI) { 3653 ParmVarDecl *Param = 3654 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3655 Params.push_back(Param); 3656 } 3657 } else { 3658 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3659 "Should not need args for typedef of non-prototype fn"); 3660 } 3661 // Finally, we know we have the right number of parameters, install them. 3662 NewFD->setParams(Params.data(), Params.size()); 3663 3664 // If the declarator is a template-id, translate the parser's template 3665 // argument list into our AST format. 3666 bool HasExplicitTemplateArgs = false; 3667 TemplateArgumentListInfo TemplateArgs; 3668 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3669 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3670 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3671 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3672 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3673 TemplateId->getTemplateArgs(), 3674 TemplateId->NumArgs); 3675 translateTemplateArguments(TemplateArgsPtr, 3676 TemplateArgs); 3677 TemplateArgsPtr.release(); 3678 3679 HasExplicitTemplateArgs = true; 3680 3681 if (FunctionTemplate) { 3682 // FIXME: Diagnose function template with explicit template 3683 // arguments. 3684 HasExplicitTemplateArgs = false; 3685 } else if (!isFunctionTemplateSpecialization && 3686 !D.getDeclSpec().isFriendSpecified()) { 3687 // We have encountered something that the user meant to be a 3688 // specialization (because it has explicitly-specified template 3689 // arguments) but that was not introduced with a "template<>" (or had 3690 // too few of them). 3691 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3692 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3693 << FixItHint::CreateInsertion( 3694 D.getDeclSpec().getSourceRange().getBegin(), 3695 "template<> "); 3696 isFunctionTemplateSpecialization = true; 3697 } else { 3698 // "friend void foo<>(int);" is an implicit specialization decl. 3699 isFunctionTemplateSpecialization = true; 3700 } 3701 } else if (isFriend && isFunctionTemplateSpecialization) { 3702 // This combination is only possible in a recovery case; the user 3703 // wrote something like: 3704 // template <> friend void foo(int); 3705 // which we're recovering from as if the user had written: 3706 // friend void foo<>(int); 3707 // Go ahead and fake up a template id. 3708 HasExplicitTemplateArgs = true; 3709 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3710 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3711 } 3712 3713 // If it's a friend (and only if it's a friend), it's possible 3714 // that either the specialized function type or the specialized 3715 // template is dependent, and therefore matching will fail. In 3716 // this case, don't check the specialization yet. 3717 if (isFunctionTemplateSpecialization && isFriend && 3718 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3719 assert(HasExplicitTemplateArgs && 3720 "friend function specialization without template args"); 3721 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3722 Previous)) 3723 NewFD->setInvalidDecl(); 3724 } else if (isFunctionTemplateSpecialization) { 3725 if (CheckFunctionTemplateSpecialization(NewFD, 3726 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3727 Previous)) 3728 NewFD->setInvalidDecl(); 3729 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3730 if (CheckMemberSpecialization(NewFD, Previous)) 3731 NewFD->setInvalidDecl(); 3732 } 3733 3734 // Perform semantic checking on the function declaration. 3735 bool OverloadableAttrRequired = false; // FIXME: HACK! 3736 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3737 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3738 3739 assert((NewFD->isInvalidDecl() || !Redeclaration || 3740 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3741 "previous declaration set still overloaded"); 3742 3743 NamedDecl *PrincipalDecl = (FunctionTemplate 3744 ? cast<NamedDecl>(FunctionTemplate) 3745 : NewFD); 3746 3747 if (isFriend && Redeclaration) { 3748 AccessSpecifier Access = AS_public; 3749 if (!NewFD->isInvalidDecl()) 3750 Access = NewFD->getPreviousDeclaration()->getAccess(); 3751 3752 NewFD->setAccess(Access); 3753 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3754 3755 PrincipalDecl->setObjectOfFriendDecl(true); 3756 } 3757 3758 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3759 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3760 PrincipalDecl->setNonMemberOperator(); 3761 3762 // If we have a function template, check the template parameter 3763 // list. This will check and merge default template arguments. 3764 if (FunctionTemplate) { 3765 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3766 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3767 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3768 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3769 : TPC_FunctionTemplate); 3770 } 3771 3772 if (NewFD->isInvalidDecl()) { 3773 // Ignore all the rest of this. 3774 } else if (!Redeclaration) { 3775 // Fake up an access specifier if it's supposed to be a class member. 3776 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 3777 NewFD->setAccess(AS_public); 3778 3779 // Qualified decls generally require a previous declaration. 3780 if (D.getCXXScopeSpec().isSet()) { 3781 // ...with the major exception of templated-scope or 3782 // dependent-scope friend declarations. 3783 3784 // TODO: we currently also suppress this check in dependent 3785 // contexts because (1) the parameter depth will be off when 3786 // matching friend templates and (2) we might actually be 3787 // selecting a friend based on a dependent factor. But there 3788 // are situations where these conditions don't apply and we 3789 // can actually do this check immediately. 3790 if (isFriend && 3791 (NumMatchedTemplateParamLists || 3792 D.getCXXScopeSpec().getScopeRep()->isDependent() || 3793 CurContext->isDependentContext())) { 3794 // ignore these 3795 } else { 3796 // The user tried to provide an out-of-line definition for a 3797 // function that is a member of a class or namespace, but there 3798 // was no such member function declared (C++ [class.mfct]p2, 3799 // C++ [namespace.memdef]p2). For example: 3800 // 3801 // class X { 3802 // void f() const; 3803 // }; 3804 // 3805 // void X::f() { } // ill-formed 3806 // 3807 // Complain about this problem, and attempt to suggest close 3808 // matches (e.g., those that differ only in cv-qualifiers and 3809 // whether the parameter types are references). 3810 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3811 << Name << DC << D.getCXXScopeSpec().getRange(); 3812 NewFD->setInvalidDecl(); 3813 3814 DiagnoseInvalidRedeclaration(*this, NewFD); 3815 } 3816 3817 // Unqualified local friend declarations are required to resolve 3818 // to something. 3819 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 3820 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 3821 NewFD->setInvalidDecl(); 3822 DiagnoseInvalidRedeclaration(*this, NewFD); 3823 } 3824 3825 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 3826 !isFriend && !isFunctionTemplateSpecialization && 3827 !isExplicitSpecialization) { 3828 // An out-of-line member function declaration must also be a 3829 // definition (C++ [dcl.meaning]p1). 3830 // Note that this is not the case for explicit specializations of 3831 // function templates or member functions of class templates, per 3832 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3833 // for compatibility with old SWIG code which likes to generate them. 3834 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3835 << D.getCXXScopeSpec().getRange(); 3836 } 3837 3838 // Handle attributes. We need to have merged decls when handling attributes 3839 // (for example to check for conflicts, etc). 3840 // FIXME: This needs to happen before we merge declarations. Then, 3841 // let attribute merging cope with attribute conflicts. 3842 ProcessDeclAttributes(S, NewFD, D); 3843 3844 // attributes declared post-definition are currently ignored 3845 // FIXME: This should happen during attribute merging 3846 if (Redeclaration && Previous.isSingleResult()) { 3847 const FunctionDecl *Def; 3848 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3849 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3850 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3851 Diag(Def->getLocation(), diag::note_previous_definition); 3852 } 3853 } 3854 3855 AddKnownFunctionAttributes(NewFD); 3856 3857 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3858 // If a function name is overloadable in C, then every function 3859 // with that name must be marked "overloadable". 3860 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3861 << Redeclaration << NewFD; 3862 if (!Previous.empty()) 3863 Diag(Previous.getRepresentativeDecl()->getLocation(), 3864 diag::note_attribute_overloadable_prev_overload); 3865 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3866 } 3867 3868 if (NewFD->hasAttr<OverloadableAttr>() && 3869 !NewFD->getType()->getAs<FunctionProtoType>()) { 3870 Diag(NewFD->getLocation(), 3871 diag::err_attribute_overloadable_no_prototype) 3872 << NewFD; 3873 3874 // Turn this into a variadic function with no parameters. 3875 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3876 QualType R = Context.getFunctionType(FT->getResultType(), 3877 0, 0, true, 0, false, false, 0, 0, 3878 FT->getExtInfo()); 3879 NewFD->setType(R); 3880 } 3881 3882 // If there's a #pragma GCC visibility in scope, and this isn't a class 3883 // member, set the visibility of this function. 3884 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3885 AddPushedVisibilityAttribute(NewFD); 3886 3887 // If this is a locally-scoped extern C function, update the 3888 // map of such names. 3889 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3890 && !NewFD->isInvalidDecl()) 3891 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3892 3893 // Set this FunctionDecl's range up to the right paren. 3894 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3895 3896 if (FunctionTemplate && NewFD->isInvalidDecl()) 3897 FunctionTemplate->setInvalidDecl(); 3898 3899 if (FunctionTemplate) 3900 return FunctionTemplate; 3901 3902 MarkUnusedFileScopedDecl(NewFD); 3903 3904 CheckClassMemberNameAttributes(*this, NewFD); 3905 3906 return NewFD; 3907} 3908 3909/// \brief Perform semantic checking of a new function declaration. 3910/// 3911/// Performs semantic analysis of the new function declaration 3912/// NewFD. This routine performs all semantic checking that does not 3913/// require the actual declarator involved in the declaration, and is 3914/// used both for the declaration of functions as they are parsed 3915/// (called via ActOnDeclarator) and for the declaration of functions 3916/// that have been instantiated via C++ template instantiation (called 3917/// via InstantiateDecl). 3918/// 3919/// \param IsExplicitSpecialiation whether this new function declaration is 3920/// an explicit specialization of the previous declaration. 3921/// 3922/// This sets NewFD->isInvalidDecl() to true if there was an error. 3923void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3924 LookupResult &Previous, 3925 bool IsExplicitSpecialization, 3926 bool &Redeclaration, 3927 bool &OverloadableAttrRequired) { 3928 // If NewFD is already known erroneous, don't do any of this checking. 3929 if (NewFD->isInvalidDecl()) { 3930 // If this is a class member, mark the class invalid immediately. 3931 // This avoids some consistency errors later. 3932 if (isa<CXXMethodDecl>(NewFD)) 3933 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3934 3935 return; 3936 } 3937 3938 if (NewFD->getResultType()->isVariablyModifiedType()) { 3939 // Functions returning a variably modified type violate C99 6.7.5.2p2 3940 // because all functions have linkage. 3941 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3942 return NewFD->setInvalidDecl(); 3943 } 3944 3945 if (NewFD->isMain()) 3946 CheckMain(NewFD); 3947 3948 // Check for a previous declaration of this name. 3949 if (Previous.empty() && NewFD->isExternC()) { 3950 // Since we did not find anything by this name and we're declaring 3951 // an extern "C" function, look for a non-visible extern "C" 3952 // declaration with the same name. 3953 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3954 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3955 if (Pos != LocallyScopedExternalDecls.end()) 3956 Previous.addDecl(Pos->second); 3957 } 3958 3959 // Merge or overload the declaration with an existing declaration of 3960 // the same name, if appropriate. 3961 if (!Previous.empty()) { 3962 // Determine whether NewFD is an overload of PrevDecl or 3963 // a declaration that requires merging. If it's an overload, 3964 // there's no more work to do here; we'll just add the new 3965 // function to the scope. 3966 3967 NamedDecl *OldDecl = 0; 3968 if (!AllowOverloadingOfFunction(Previous, Context)) { 3969 Redeclaration = true; 3970 OldDecl = Previous.getFoundDecl(); 3971 } else { 3972 if (!getLangOptions().CPlusPlus) 3973 OverloadableAttrRequired = true; 3974 3975 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3976 /*NewIsUsingDecl*/ false)) { 3977 case Ovl_Match: 3978 Redeclaration = true; 3979 break; 3980 3981 case Ovl_NonFunction: 3982 Redeclaration = true; 3983 break; 3984 3985 case Ovl_Overload: 3986 Redeclaration = false; 3987 break; 3988 } 3989 } 3990 3991 if (Redeclaration) { 3992 // NewFD and OldDecl represent declarations that need to be 3993 // merged. 3994 if (MergeFunctionDecl(NewFD, OldDecl)) 3995 return NewFD->setInvalidDecl(); 3996 3997 Previous.clear(); 3998 Previous.addDecl(OldDecl); 3999 4000 if (FunctionTemplateDecl *OldTemplateDecl 4001 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4002 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4003 FunctionTemplateDecl *NewTemplateDecl 4004 = NewFD->getDescribedFunctionTemplate(); 4005 assert(NewTemplateDecl && "Template/non-template mismatch"); 4006 if (CXXMethodDecl *Method 4007 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4008 Method->setAccess(OldTemplateDecl->getAccess()); 4009 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4010 } 4011 4012 // If this is an explicit specialization of a member that is a function 4013 // template, mark it as a member specialization. 4014 if (IsExplicitSpecialization && 4015 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4016 NewTemplateDecl->setMemberSpecialization(); 4017 assert(OldTemplateDecl->isMemberSpecialization()); 4018 } 4019 } else { 4020 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4021 NewFD->setAccess(OldDecl->getAccess()); 4022 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4023 } 4024 } 4025 } 4026 4027 // Semantic checking for this function declaration (in isolation). 4028 if (getLangOptions().CPlusPlus) { 4029 // C++-specific checks. 4030 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4031 CheckConstructor(Constructor); 4032 } else if (CXXDestructorDecl *Destructor = 4033 dyn_cast<CXXDestructorDecl>(NewFD)) { 4034 CXXRecordDecl *Record = Destructor->getParent(); 4035 QualType ClassType = Context.getTypeDeclType(Record); 4036 4037 // FIXME: Shouldn't we be able to perform this check even when the class 4038 // type is dependent? Both gcc and edg can handle that. 4039 if (!ClassType->isDependentType()) { 4040 DeclarationName Name 4041 = Context.DeclarationNames.getCXXDestructorName( 4042 Context.getCanonicalType(ClassType)); 4043 if (NewFD->getDeclName() != Name) { 4044 Diag(NewFD->getLocation(), diag::err_destructor_name); 4045 return NewFD->setInvalidDecl(); 4046 } 4047 } 4048 } else if (CXXConversionDecl *Conversion 4049 = dyn_cast<CXXConversionDecl>(NewFD)) { 4050 ActOnConversionDeclarator(Conversion); 4051 } 4052 4053 // Find any virtual functions that this function overrides. 4054 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4055 if (!Method->isFunctionTemplateSpecialization() && 4056 !Method->getDescribedFunctionTemplate()) { 4057 if (AddOverriddenMethods(Method->getParent(), Method)) { 4058 // If the function was marked as "static", we have a problem. 4059 if (NewFD->getStorageClass() == SC_Static) { 4060 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4061 << NewFD->getDeclName(); 4062 for (CXXMethodDecl::method_iterator 4063 Overridden = Method->begin_overridden_methods(), 4064 OverriddenEnd = Method->end_overridden_methods(); 4065 Overridden != OverriddenEnd; 4066 ++Overridden) { 4067 Diag((*Overridden)->getLocation(), 4068 diag::note_overridden_virtual_function); 4069 } 4070 } 4071 } 4072 } 4073 } 4074 4075 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4076 if (NewFD->isOverloadedOperator() && 4077 CheckOverloadedOperatorDeclaration(NewFD)) 4078 return NewFD->setInvalidDecl(); 4079 4080 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4081 if (NewFD->getLiteralIdentifier() && 4082 CheckLiteralOperatorDeclaration(NewFD)) 4083 return NewFD->setInvalidDecl(); 4084 4085 // In C++, check default arguments now that we have merged decls. Unless 4086 // the lexical context is the class, because in this case this is done 4087 // during delayed parsing anyway. 4088 if (!CurContext->isRecord()) 4089 CheckCXXDefaultArguments(NewFD); 4090 } 4091} 4092 4093void Sema::CheckMain(FunctionDecl* FD) { 4094 // C++ [basic.start.main]p3: A program that declares main to be inline 4095 // or static is ill-formed. 4096 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4097 // shall not appear in a declaration of main. 4098 // static main is not an error under C99, but we should warn about it. 4099 bool isInline = FD->isInlineSpecified(); 4100 bool isStatic = FD->getStorageClass() == SC_Static; 4101 if (isInline || isStatic) { 4102 unsigned diagID = diag::warn_unusual_main_decl; 4103 if (isInline || getLangOptions().CPlusPlus) 4104 diagID = diag::err_unusual_main_decl; 4105 4106 int which = isStatic + (isInline << 1) - 1; 4107 Diag(FD->getLocation(), diagID) << which; 4108 } 4109 4110 QualType T = FD->getType(); 4111 assert(T->isFunctionType() && "function decl is not of function type"); 4112 const FunctionType* FT = T->getAs<FunctionType>(); 4113 4114 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4115 TypeSourceInfo *TSI = FD->getTypeSourceInfo(); 4116 TypeLoc TL = TSI->getTypeLoc(); 4117 const SemaDiagnosticBuilder& D = Diag(FD->getTypeSpecStartLoc(), 4118 diag::err_main_returns_nonint); 4119 if (FunctionTypeLoc* PTL = dyn_cast<FunctionTypeLoc>(&TL)) { 4120 D << FixItHint::CreateReplacement(PTL->getResultLoc().getSourceRange(), 4121 "int"); 4122 } 4123 FD->setInvalidDecl(true); 4124 } 4125 4126 // Treat protoless main() as nullary. 4127 if (isa<FunctionNoProtoType>(FT)) return; 4128 4129 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4130 unsigned nparams = FTP->getNumArgs(); 4131 assert(FD->getNumParams() == nparams); 4132 4133 bool HasExtraParameters = (nparams > 3); 4134 4135 // Darwin passes an undocumented fourth argument of type char**. If 4136 // other platforms start sprouting these, the logic below will start 4137 // getting shifty. 4138 if (nparams == 4 && 4139 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4140 HasExtraParameters = false; 4141 4142 if (HasExtraParameters) { 4143 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4144 FD->setInvalidDecl(true); 4145 nparams = 3; 4146 } 4147 4148 // FIXME: a lot of the following diagnostics would be improved 4149 // if we had some location information about types. 4150 4151 QualType CharPP = 4152 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4153 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4154 4155 for (unsigned i = 0; i < nparams; ++i) { 4156 QualType AT = FTP->getArgType(i); 4157 4158 bool mismatch = true; 4159 4160 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4161 mismatch = false; 4162 else if (Expected[i] == CharPP) { 4163 // As an extension, the following forms are okay: 4164 // char const ** 4165 // char const * const * 4166 // char * const * 4167 4168 QualifierCollector qs; 4169 const PointerType* PT; 4170 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4171 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4172 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4173 qs.removeConst(); 4174 mismatch = !qs.empty(); 4175 } 4176 } 4177 4178 if (mismatch) { 4179 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4180 // TODO: suggest replacing given type with expected type 4181 FD->setInvalidDecl(true); 4182 } 4183 } 4184 4185 if (nparams == 1 && !FD->isInvalidDecl()) { 4186 Diag(FD->getLocation(), diag::warn_main_one_arg); 4187 } 4188 4189 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 4190 Diag(FD->getLocation(), diag::err_main_template_decl); 4191 FD->setInvalidDecl(); 4192 } 4193} 4194 4195bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4196 // FIXME: Need strict checking. In C89, we need to check for 4197 // any assignment, increment, decrement, function-calls, or 4198 // commas outside of a sizeof. In C99, it's the same list, 4199 // except that the aforementioned are allowed in unevaluated 4200 // expressions. Everything else falls under the 4201 // "may accept other forms of constant expressions" exception. 4202 // (We never end up here for C++, so the constant expression 4203 // rules there don't matter.) 4204 if (Init->isConstantInitializer(Context, false)) 4205 return false; 4206 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4207 << Init->getSourceRange(); 4208 return true; 4209} 4210 4211void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4212 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4213} 4214 4215/// AddInitializerToDecl - Adds the initializer Init to the 4216/// declaration dcl. If DirectInit is true, this is C++ direct 4217/// initialization rather than copy initialization. 4218void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4219 // If there is no declaration, there was an error parsing it. Just ignore 4220 // the initializer. 4221 if (RealDecl == 0) 4222 return; 4223 4224 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4225 // With declarators parsed the way they are, the parser cannot 4226 // distinguish between a normal initializer and a pure-specifier. 4227 // Thus this grotesque test. 4228 IntegerLiteral *IL; 4229 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4230 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4231 CheckPureMethod(Method, Init->getSourceRange()); 4232 else { 4233 Diag(Method->getLocation(), diag::err_member_function_initialization) 4234 << Method->getDeclName() << Init->getSourceRange(); 4235 Method->setInvalidDecl(); 4236 } 4237 return; 4238 } 4239 4240 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4241 if (!VDecl) { 4242 if (getLangOptions().CPlusPlus && 4243 RealDecl->getLexicalDeclContext()->isRecord() && 4244 isa<NamedDecl>(RealDecl)) 4245 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4246 else 4247 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4248 RealDecl->setInvalidDecl(); 4249 return; 4250 } 4251 4252 4253 4254 // A definition must end up with a complete type, which means it must be 4255 // complete with the restriction that an array type might be completed by the 4256 // initializer; note that later code assumes this restriction. 4257 QualType BaseDeclType = VDecl->getType(); 4258 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4259 BaseDeclType = Array->getElementType(); 4260 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4261 diag::err_typecheck_decl_incomplete_type)) { 4262 RealDecl->setInvalidDecl(); 4263 return; 4264 } 4265 4266 // The variable can not have an abstract class type. 4267 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4268 diag::err_abstract_type_in_decl, 4269 AbstractVariableType)) 4270 VDecl->setInvalidDecl(); 4271 4272 const VarDecl *Def; 4273 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4274 Diag(VDecl->getLocation(), diag::err_redefinition) 4275 << VDecl->getDeclName(); 4276 Diag(Def->getLocation(), diag::note_previous_definition); 4277 VDecl->setInvalidDecl(); 4278 return; 4279 } 4280 4281 // C++ [class.static.data]p4 4282 // If a static data member is of const integral or const 4283 // enumeration type, its declaration in the class definition can 4284 // specify a constant-initializer which shall be an integral 4285 // constant expression (5.19). In that case, the member can appear 4286 // in integral constant expressions. The member shall still be 4287 // defined in a namespace scope if it is used in the program and the 4288 // namespace scope definition shall not contain an initializer. 4289 // 4290 // We already performed a redefinition check above, but for static 4291 // data members we also need to check whether there was an in-class 4292 // declaration with an initializer. 4293 const VarDecl* PrevInit = 0; 4294 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4295 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4296 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4297 return; 4298 } 4299 4300 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4301 getCurFunction()->setHasBranchProtectedScope(); 4302 4303 // Capture the variable that is being initialized and the style of 4304 // initialization. 4305 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4306 4307 // FIXME: Poor source location information. 4308 InitializationKind Kind 4309 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4310 Init->getLocStart(), 4311 Init->getLocEnd()) 4312 : InitializationKind::CreateCopy(VDecl->getLocation(), 4313 Init->getLocStart()); 4314 4315 // Get the decls type and save a reference for later, since 4316 // CheckInitializerTypes may change it. 4317 QualType DclT = VDecl->getType(), SavT = DclT; 4318 if (VDecl->isLocalVarDecl()) { 4319 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4320 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4321 VDecl->setInvalidDecl(); 4322 } else if (!VDecl->isInvalidDecl()) { 4323 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4324 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4325 MultiExprArg(*this, &Init, 1), 4326 &DclT); 4327 if (Result.isInvalid()) { 4328 VDecl->setInvalidDecl(); 4329 return; 4330 } 4331 4332 Init = Result.takeAs<Expr>(); 4333 4334 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4335 // Don't check invalid declarations to avoid emitting useless diagnostics. 4336 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4337 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4338 CheckForConstantInitializer(Init, DclT); 4339 } 4340 } 4341 } else if (VDecl->isStaticDataMember() && 4342 VDecl->getLexicalDeclContext()->isRecord()) { 4343 // This is an in-class initialization for a static data member, e.g., 4344 // 4345 // struct S { 4346 // static const int value = 17; 4347 // }; 4348 4349 // Try to perform the initialization regardless. 4350 if (!VDecl->isInvalidDecl()) { 4351 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4352 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4353 MultiExprArg(*this, &Init, 1), 4354 &DclT); 4355 if (Result.isInvalid()) { 4356 VDecl->setInvalidDecl(); 4357 return; 4358 } 4359 4360 Init = Result.takeAs<Expr>(); 4361 } 4362 4363 // C++ [class.mem]p4: 4364 // A member-declarator can contain a constant-initializer only 4365 // if it declares a static member (9.4) of const integral or 4366 // const enumeration type, see 9.4.2. 4367 QualType T = VDecl->getType(); 4368 4369 // Do nothing on dependent types. 4370 if (T->isDependentType()) { 4371 4372 // Require constness. 4373 } else if (!T.isConstQualified()) { 4374 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4375 << Init->getSourceRange(); 4376 VDecl->setInvalidDecl(); 4377 4378 // We allow integer constant expressions in all cases. 4379 } else if (T->isIntegralOrEnumerationType()) { 4380 if (!Init->isValueDependent()) { 4381 // Check whether the expression is a constant expression. 4382 llvm::APSInt Value; 4383 SourceLocation Loc; 4384 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4385 Diag(Loc, diag::err_in_class_initializer_non_constant) 4386 << Init->getSourceRange(); 4387 VDecl->setInvalidDecl(); 4388 } 4389 } 4390 4391 // We allow floating-point constants as an extension in C++03, and 4392 // C++0x has far more complicated rules that we don't really 4393 // implement fully. 4394 } else { 4395 bool Allowed = false; 4396 if (getLangOptions().CPlusPlus0x) { 4397 Allowed = T->isLiteralType(); 4398 } else if (T->isFloatingType()) { // also permits complex, which is ok 4399 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4400 << T << Init->getSourceRange(); 4401 Allowed = true; 4402 } 4403 4404 if (!Allowed) { 4405 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4406 << T << Init->getSourceRange(); 4407 VDecl->setInvalidDecl(); 4408 4409 // TODO: there are probably expressions that pass here that shouldn't. 4410 } else if (!Init->isValueDependent() && 4411 !Init->isConstantInitializer(Context, false)) { 4412 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4413 << Init->getSourceRange(); 4414 VDecl->setInvalidDecl(); 4415 } 4416 } 4417 } else if (VDecl->isFileVarDecl()) { 4418 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4419 (!getLangOptions().CPlusPlus || 4420 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4421 Diag(VDecl->getLocation(), diag::warn_extern_init); 4422 if (!VDecl->isInvalidDecl()) { 4423 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4424 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4425 MultiExprArg(*this, &Init, 1), 4426 &DclT); 4427 if (Result.isInvalid()) { 4428 VDecl->setInvalidDecl(); 4429 return; 4430 } 4431 4432 Init = Result.takeAs<Expr>(); 4433 } 4434 4435 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4436 // Don't check invalid declarations to avoid emitting useless diagnostics. 4437 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4438 // C99 6.7.8p4. All file scoped initializers need to be constant. 4439 CheckForConstantInitializer(Init, DclT); 4440 } 4441 } 4442 // If the type changed, it means we had an incomplete type that was 4443 // completed by the initializer. For example: 4444 // int ary[] = { 1, 3, 5 }; 4445 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4446 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4447 VDecl->setType(DclT); 4448 Init->setType(DclT); 4449 } 4450 4451 4452 // If this variable is a local declaration with record type, make sure it 4453 // doesn't have a flexible member initialization. We only support this as a 4454 // global/static definition. 4455 if (VDecl->hasLocalStorage()) 4456 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4457 if (RT->getDecl()->hasFlexibleArrayMember()) { 4458 // Check whether the initializer tries to initialize the flexible 4459 // array member itself to anything other than an empty initializer list. 4460 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 4461 unsigned Index = std::distance(RT->getDecl()->field_begin(), 4462 RT->getDecl()->field_end()) - 1; 4463 if (Index < ILE->getNumInits() && 4464 !(isa<InitListExpr>(ILE->getInit(Index)) && 4465 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 4466 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4467 VDecl->setInvalidDecl(); 4468 } 4469 } 4470 } 4471 4472 // Check any implicit conversions within the expression. 4473 CheckImplicitConversions(Init, VDecl->getLocation()); 4474 4475 Init = MaybeCreateCXXExprWithTemporaries(Init); 4476 // Attach the initializer to the decl. 4477 VDecl->setInit(Init); 4478 4479 if (getLangOptions().CPlusPlus) { 4480 if (!VDecl->isInvalidDecl() && 4481 !VDecl->getDeclContext()->isDependentContext() && 4482 VDecl->hasGlobalStorage() && !VDecl->isStaticLocal() && 4483 !Init->isConstantInitializer(Context, 4484 VDecl->getType()->isReferenceType())) 4485 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4486 << Init->getSourceRange(); 4487 4488 // Make sure we mark the destructor as used if necessary. 4489 QualType InitType = VDecl->getType(); 4490 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4491 InitType = Context.getBaseElementType(Array); 4492 if (const RecordType *Record = InitType->getAs<RecordType>()) 4493 FinalizeVarWithDestructor(VDecl, Record); 4494 } 4495 4496 return; 4497} 4498 4499/// ActOnInitializerError - Given that there was an error parsing an 4500/// initializer for the given declaration, try to return to some form 4501/// of sanity. 4502void Sema::ActOnInitializerError(Decl *D) { 4503 // Our main concern here is re-establishing invariants like "a 4504 // variable's type is either dependent or complete". 4505 if (!D || D->isInvalidDecl()) return; 4506 4507 VarDecl *VD = dyn_cast<VarDecl>(D); 4508 if (!VD) return; 4509 4510 QualType Ty = VD->getType(); 4511 if (Ty->isDependentType()) return; 4512 4513 // Require a complete type. 4514 if (RequireCompleteType(VD->getLocation(), 4515 Context.getBaseElementType(Ty), 4516 diag::err_typecheck_decl_incomplete_type)) { 4517 VD->setInvalidDecl(); 4518 return; 4519 } 4520 4521 // Require an abstract type. 4522 if (RequireNonAbstractType(VD->getLocation(), Ty, 4523 diag::err_abstract_type_in_decl, 4524 AbstractVariableType)) { 4525 VD->setInvalidDecl(); 4526 return; 4527 } 4528 4529 // Don't bother complaining about constructors or destructors, 4530 // though. 4531} 4532 4533void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4534 bool TypeContainsUndeducedAuto) { 4535 // If there is no declaration, there was an error parsing it. Just ignore it. 4536 if (RealDecl == 0) 4537 return; 4538 4539 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4540 QualType Type = Var->getType(); 4541 4542 // C++0x [dcl.spec.auto]p3 4543 if (TypeContainsUndeducedAuto) { 4544 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4545 << Var->getDeclName() << Type; 4546 Var->setInvalidDecl(); 4547 return; 4548 } 4549 4550 switch (Var->isThisDeclarationADefinition()) { 4551 case VarDecl::Definition: 4552 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4553 break; 4554 4555 // We have an out-of-line definition of a static data member 4556 // that has an in-class initializer, so we type-check this like 4557 // a declaration. 4558 // 4559 // Fall through 4560 4561 case VarDecl::DeclarationOnly: 4562 // It's only a declaration. 4563 4564 // Block scope. C99 6.7p7: If an identifier for an object is 4565 // declared with no linkage (C99 6.2.2p6), the type for the 4566 // object shall be complete. 4567 if (!Type->isDependentType() && Var->isLocalVarDecl() && 4568 !Var->getLinkage() && !Var->isInvalidDecl() && 4569 RequireCompleteType(Var->getLocation(), Type, 4570 diag::err_typecheck_decl_incomplete_type)) 4571 Var->setInvalidDecl(); 4572 4573 // Make sure that the type is not abstract. 4574 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4575 RequireNonAbstractType(Var->getLocation(), Type, 4576 diag::err_abstract_type_in_decl, 4577 AbstractVariableType)) 4578 Var->setInvalidDecl(); 4579 return; 4580 4581 case VarDecl::TentativeDefinition: 4582 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4583 // object that has file scope without an initializer, and without a 4584 // storage-class specifier or with the storage-class specifier "static", 4585 // constitutes a tentative definition. Note: A tentative definition with 4586 // external linkage is valid (C99 6.2.2p5). 4587 if (!Var->isInvalidDecl()) { 4588 if (const IncompleteArrayType *ArrayT 4589 = Context.getAsIncompleteArrayType(Type)) { 4590 if (RequireCompleteType(Var->getLocation(), 4591 ArrayT->getElementType(), 4592 diag::err_illegal_decl_array_incomplete_type)) 4593 Var->setInvalidDecl(); 4594 } else if (Var->getStorageClass() == SC_Static) { 4595 // C99 6.9.2p3: If the declaration of an identifier for an object is 4596 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4597 // declared type shall not be an incomplete type. 4598 // NOTE: code such as the following 4599 // static struct s; 4600 // struct s { int a; }; 4601 // is accepted by gcc. Hence here we issue a warning instead of 4602 // an error and we do not invalidate the static declaration. 4603 // NOTE: to avoid multiple warnings, only check the first declaration. 4604 if (Var->getPreviousDeclaration() == 0) 4605 RequireCompleteType(Var->getLocation(), Type, 4606 diag::ext_typecheck_decl_incomplete_type); 4607 } 4608 } 4609 4610 // Record the tentative definition; we're done. 4611 if (!Var->isInvalidDecl()) 4612 TentativeDefinitions.push_back(Var); 4613 return; 4614 } 4615 4616 // Provide a specific diagnostic for uninitialized variable 4617 // definitions with incomplete array type. 4618 if (Type->isIncompleteArrayType()) { 4619 Diag(Var->getLocation(), 4620 diag::err_typecheck_incomplete_array_needs_initializer); 4621 Var->setInvalidDecl(); 4622 return; 4623 } 4624 4625 // Provide a specific diagnostic for uninitialized variable 4626 // definitions with reference type. 4627 if (Type->isReferenceType()) { 4628 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4629 << Var->getDeclName() 4630 << SourceRange(Var->getLocation(), Var->getLocation()); 4631 Var->setInvalidDecl(); 4632 return; 4633 } 4634 4635 // Do not attempt to type-check the default initializer for a 4636 // variable with dependent type. 4637 if (Type->isDependentType()) 4638 return; 4639 4640 if (Var->isInvalidDecl()) 4641 return; 4642 4643 if (RequireCompleteType(Var->getLocation(), 4644 Context.getBaseElementType(Type), 4645 diag::err_typecheck_decl_incomplete_type)) { 4646 Var->setInvalidDecl(); 4647 return; 4648 } 4649 4650 // The variable can not have an abstract class type. 4651 if (RequireNonAbstractType(Var->getLocation(), Type, 4652 diag::err_abstract_type_in_decl, 4653 AbstractVariableType)) { 4654 Var->setInvalidDecl(); 4655 return; 4656 } 4657 4658 const RecordType *Record 4659 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4660 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4661 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4662 // C++03 [dcl.init]p9: 4663 // If no initializer is specified for an object, and the 4664 // object is of (possibly cv-qualified) non-POD class type (or 4665 // array thereof), the object shall be default-initialized; if 4666 // the object is of const-qualified type, the underlying class 4667 // type shall have a user-declared default 4668 // constructor. Otherwise, if no initializer is specified for 4669 // a non- static object, the object and its subobjects, if 4670 // any, have an indeterminate initial value); if the object 4671 // or any of its subobjects are of const-qualified type, the 4672 // program is ill-formed. 4673 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4674 } else { 4675 // Check for jumps past the implicit initializer. C++0x 4676 // clarifies that this applies to a "variable with automatic 4677 // storage duration", not a "local variable". 4678 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4679 getCurFunction()->setHasBranchProtectedScope(); 4680 4681 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4682 InitializationKind Kind 4683 = InitializationKind::CreateDefault(Var->getLocation()); 4684 4685 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4686 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4687 MultiExprArg(*this, 0, 0)); 4688 if (Init.isInvalid()) 4689 Var->setInvalidDecl(); 4690 else if (Init.get()) { 4691 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4692 4693 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4694 Var->hasGlobalStorage() && !Var->isStaticLocal() && 4695 !Var->getDeclContext()->isDependentContext() && 4696 !Var->getInit()->isConstantInitializer(Context, false)) 4697 Diag(Var->getLocation(), diag::warn_global_constructor); 4698 } 4699 } 4700 4701 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4702 FinalizeVarWithDestructor(Var, Record); 4703 } 4704} 4705 4706Sema::DeclGroupPtrTy 4707Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4708 Decl **Group, unsigned NumDecls) { 4709 llvm::SmallVector<Decl*, 8> Decls; 4710 4711 if (DS.isTypeSpecOwned()) 4712 Decls.push_back(DS.getRepAsDecl()); 4713 4714 for (unsigned i = 0; i != NumDecls; ++i) 4715 if (Decl *D = Group[i]) 4716 Decls.push_back(D); 4717 4718 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4719 Decls.data(), Decls.size())); 4720} 4721 4722 4723/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4724/// to introduce parameters into function prototype scope. 4725Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4726 const DeclSpec &DS = D.getDeclSpec(); 4727 4728 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4729 VarDecl::StorageClass StorageClass = SC_None; 4730 VarDecl::StorageClass StorageClassAsWritten = SC_None; 4731 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4732 StorageClass = SC_Register; 4733 StorageClassAsWritten = SC_Register; 4734 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4735 Diag(DS.getStorageClassSpecLoc(), 4736 diag::err_invalid_storage_class_in_func_decl); 4737 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4738 } 4739 4740 if (D.getDeclSpec().isThreadSpecified()) 4741 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4742 4743 DiagnoseFunctionSpecifiers(D); 4744 4745 // Check that there are no default arguments inside the type of this 4746 // parameter (C++ only). 4747 if (getLangOptions().CPlusPlus) 4748 CheckExtraCXXDefaultArguments(D); 4749 4750 TagDecl *OwnedDecl = 0; 4751 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4752 QualType parmDeclType = TInfo->getType(); 4753 4754 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4755 // C++ [dcl.fct]p6: 4756 // Types shall not be defined in return or parameter types. 4757 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4758 << Context.getTypeDeclType(OwnedDecl); 4759 } 4760 4761 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4762 IdentifierInfo *II = D.getIdentifier(); 4763 if (II) { 4764 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4765 ForRedeclaration); 4766 LookupName(R, S); 4767 if (R.isSingleResult()) { 4768 NamedDecl *PrevDecl = R.getFoundDecl(); 4769 if (PrevDecl->isTemplateParameter()) { 4770 // Maybe we will complain about the shadowed template parameter. 4771 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4772 // Just pretend that we didn't see the previous declaration. 4773 PrevDecl = 0; 4774 } else if (S->isDeclScope(PrevDecl)) { 4775 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4776 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4777 4778 // Recover by removing the name 4779 II = 0; 4780 D.SetIdentifier(0, D.getIdentifierLoc()); 4781 D.setInvalidType(true); 4782 } 4783 } 4784 } 4785 4786 // Temporarily put parameter variables in the translation unit, not 4787 // the enclosing context. This prevents them from accidentally 4788 // looking like class members in C++. 4789 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4790 TInfo, parmDeclType, II, 4791 D.getIdentifierLoc(), 4792 StorageClass, StorageClassAsWritten); 4793 4794 if (D.isInvalidType()) 4795 New->setInvalidDecl(); 4796 4797 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4798 if (D.getCXXScopeSpec().isSet()) { 4799 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4800 << D.getCXXScopeSpec().getRange(); 4801 New->setInvalidDecl(); 4802 } 4803 4804 // Add the parameter declaration into this scope. 4805 S->AddDecl(New); 4806 if (II) 4807 IdResolver.AddDecl(New); 4808 4809 ProcessDeclAttributes(S, New, D); 4810 4811 if (New->hasAttr<BlocksAttr>()) { 4812 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4813 } 4814 return New; 4815} 4816 4817/// \brief Synthesizes a variable for a parameter arising from a 4818/// typedef. 4819ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4820 SourceLocation Loc, 4821 QualType T) { 4822 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4823 T, Context.getTrivialTypeSourceInfo(T, Loc), 4824 SC_None, SC_None, 0); 4825 Param->setImplicit(); 4826 return Param; 4827} 4828 4829void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 4830 ParmVarDecl * const *ParamEnd) { 4831 if (Diags.getDiagnosticLevel(diag::warn_unused_parameter) == 4832 Diagnostic::Ignored) 4833 return; 4834 4835 // Don't diagnose unused-parameter errors in template instantiations; we 4836 // will already have done so in the template itself. 4837 if (!ActiveTemplateInstantiations.empty()) 4838 return; 4839 4840 for (; Param != ParamEnd; ++Param) { 4841 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 4842 !(*Param)->hasAttr<UnusedAttr>()) { 4843 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 4844 << (*Param)->getDeclName(); 4845 } 4846 } 4847} 4848 4849ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4850 TypeSourceInfo *TSInfo, QualType T, 4851 IdentifierInfo *Name, 4852 SourceLocation NameLoc, 4853 VarDecl::StorageClass StorageClass, 4854 VarDecl::StorageClass StorageClassAsWritten) { 4855 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4856 adjustParameterType(T), TSInfo, 4857 StorageClass, StorageClassAsWritten, 4858 0); 4859 4860 // Parameters can not be abstract class types. 4861 // For record types, this is done by the AbstractClassUsageDiagnoser once 4862 // the class has been completely parsed. 4863 if (!CurContext->isRecord() && 4864 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4865 AbstractParamType)) 4866 New->setInvalidDecl(); 4867 4868 // Parameter declarators cannot be interface types. All ObjC objects are 4869 // passed by reference. 4870 if (T->isObjCObjectType()) { 4871 Diag(NameLoc, 4872 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4873 New->setInvalidDecl(); 4874 } 4875 4876 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4877 // duration shall not be qualified by an address-space qualifier." 4878 // Since all parameters have automatic store duration, they can not have 4879 // an address space. 4880 if (T.getAddressSpace() != 0) { 4881 Diag(NameLoc, diag::err_arg_with_address_space); 4882 New->setInvalidDecl(); 4883 } 4884 4885 return New; 4886} 4887 4888void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4889 SourceLocation LocAfterDecls) { 4890 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4891 "Not a function declarator!"); 4892 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4893 4894 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4895 // for a K&R function. 4896 if (!FTI.hasPrototype) { 4897 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4898 --i; 4899 if (FTI.ArgInfo[i].Param == 0) { 4900 llvm::SmallString<256> Code; 4901 llvm::raw_svector_ostream(Code) << " int " 4902 << FTI.ArgInfo[i].Ident->getName() 4903 << ";\n"; 4904 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4905 << FTI.ArgInfo[i].Ident 4906 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4907 4908 // Implicitly declare the argument as type 'int' for lack of a better 4909 // type. 4910 DeclSpec DS; 4911 const char* PrevSpec; // unused 4912 unsigned DiagID; // unused 4913 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4914 PrevSpec, DiagID); 4915 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4916 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4917 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4918 } 4919 } 4920 } 4921} 4922 4923Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4924 Declarator &D) { 4925 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4926 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4927 "Not a function declarator!"); 4928 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4929 4930 if (FTI.hasPrototype) { 4931 // FIXME: Diagnose arguments without names in C. 4932 } 4933 4934 Scope *ParentScope = FnBodyScope->getParent(); 4935 4936 Decl *DP = HandleDeclarator(ParentScope, D, 4937 MultiTemplateParamsArg(*this), 4938 /*IsFunctionDefinition=*/true); 4939 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4940} 4941 4942static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4943 // Don't warn about invalid declarations. 4944 if (FD->isInvalidDecl()) 4945 return false; 4946 4947 // Or declarations that aren't global. 4948 if (!FD->isGlobal()) 4949 return false; 4950 4951 // Don't warn about C++ member functions. 4952 if (isa<CXXMethodDecl>(FD)) 4953 return false; 4954 4955 // Don't warn about 'main'. 4956 if (FD->isMain()) 4957 return false; 4958 4959 // Don't warn about inline functions. 4960 if (FD->isInlineSpecified()) 4961 return false; 4962 4963 // Don't warn about function templates. 4964 if (FD->getDescribedFunctionTemplate()) 4965 return false; 4966 4967 // Don't warn about function template specializations. 4968 if (FD->isFunctionTemplateSpecialization()) 4969 return false; 4970 4971 bool MissingPrototype = true; 4972 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4973 Prev; Prev = Prev->getPreviousDeclaration()) { 4974 // Ignore any declarations that occur in function or method 4975 // scope, because they aren't visible from the header. 4976 if (Prev->getDeclContext()->isFunctionOrMethod()) 4977 continue; 4978 4979 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4980 break; 4981 } 4982 4983 return MissingPrototype; 4984} 4985 4986Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4987 // Clear the last template instantiation error context. 4988 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4989 4990 if (!D) 4991 return D; 4992 FunctionDecl *FD = 0; 4993 4994 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4995 FD = FunTmpl->getTemplatedDecl(); 4996 else 4997 FD = cast<FunctionDecl>(D); 4998 4999 // Enter a new function scope 5000 PushFunctionScope(); 5001 5002 // See if this is a redefinition. 5003 // But don't complain if we're in GNU89 mode and the previous definition 5004 // was an extern inline function. 5005 const FunctionDecl *Definition; 5006 if (FD->hasBody(Definition) && 5007 !canRedefineFunction(Definition, getLangOptions())) { 5008 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 5009 Definition->getStorageClass() == SC_Extern) 5010 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 5011 << FD->getDeclName() << getLangOptions().CPlusPlus; 5012 else 5013 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 5014 Diag(Definition->getLocation(), diag::note_previous_definition); 5015 } 5016 5017 // Builtin functions cannot be defined. 5018 if (unsigned BuiltinID = FD->getBuiltinID()) { 5019 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 5020 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 5021 FD->setInvalidDecl(); 5022 } 5023 } 5024 5025 // The return type of a function definition must be complete 5026 // (C99 6.9.1p3, C++ [dcl.fct]p6). 5027 QualType ResultType = FD->getResultType(); 5028 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 5029 !FD->isInvalidDecl() && 5030 RequireCompleteType(FD->getLocation(), ResultType, 5031 diag::err_func_def_incomplete_result)) 5032 FD->setInvalidDecl(); 5033 5034 // GNU warning -Wmissing-prototypes: 5035 // Warn if a global function is defined without a previous 5036 // prototype declaration. This warning is issued even if the 5037 // definition itself provides a prototype. The aim is to detect 5038 // global functions that fail to be declared in header files. 5039 if (ShouldWarnAboutMissingPrototype(FD)) 5040 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 5041 5042 if (FnBodyScope) 5043 PushDeclContext(FnBodyScope, FD); 5044 5045 // Check the validity of our function parameters 5046 CheckParmsForFunctionDef(FD); 5047 5048 bool ShouldCheckShadow = 5049 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 5050 5051 // Introduce our parameters into the function scope 5052 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 5053 ParmVarDecl *Param = FD->getParamDecl(p); 5054 Param->setOwningFunction(FD); 5055 5056 // If this has an identifier, add it to the scope stack. 5057 if (Param->getIdentifier() && FnBodyScope) { 5058 if (ShouldCheckShadow) 5059 CheckShadow(FnBodyScope, Param); 5060 5061 PushOnScopeChains(Param, FnBodyScope); 5062 } 5063 } 5064 5065 // Checking attributes of current function definition 5066 // dllimport attribute. 5067 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5068 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5069 // dllimport attribute cannot be directly applied to definition. 5070 if (!DA->isInherited()) { 5071 Diag(FD->getLocation(), 5072 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5073 << "dllimport"; 5074 FD->setInvalidDecl(); 5075 return FD; 5076 } 5077 5078 // Visual C++ appears to not think this is an issue, so only issue 5079 // a warning when Microsoft extensions are disabled. 5080 if (!LangOpts.Microsoft) { 5081 // If a symbol previously declared dllimport is later defined, the 5082 // attribute is ignored in subsequent references, and a warning is 5083 // emitted. 5084 Diag(FD->getLocation(), 5085 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5086 << FD->getName() << "dllimport"; 5087 } 5088 } 5089 return FD; 5090} 5091 5092/// \brief Given the set of return statements within a function body, 5093/// compute the variables that are subject to the named return value 5094/// optimization. 5095/// 5096/// Each of the variables that is subject to the named return value 5097/// optimization will be marked as NRVO variables in the AST, and any 5098/// return statement that has a marked NRVO variable as its NRVO candidate can 5099/// use the named return value optimization. 5100/// 5101/// This function applies a very simplistic algorithm for NRVO: if every return 5102/// statement in the function has the same NRVO candidate, that candidate is 5103/// the NRVO variable. 5104/// 5105/// FIXME: Employ a smarter algorithm that accounts for multiple return 5106/// statements and the lifetimes of the NRVO candidates. We should be able to 5107/// find a maximal set of NRVO variables. 5108static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5109 ReturnStmt **Returns = Scope->Returns.data(); 5110 5111 const VarDecl *NRVOCandidate = 0; 5112 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5113 if (!Returns[I]->getNRVOCandidate()) 5114 return; 5115 5116 if (!NRVOCandidate) 5117 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5118 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5119 return; 5120 } 5121 5122 if (NRVOCandidate) 5123 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5124} 5125 5126Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5127 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5128} 5129 5130Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5131 bool IsInstantiation) { 5132 FunctionDecl *FD = 0; 5133 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5134 if (FunTmpl) 5135 FD = FunTmpl->getTemplatedDecl(); 5136 else 5137 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5138 5139 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5140 5141 if (FD) { 5142 FD->setBody(Body); 5143 if (FD->isMain()) { 5144 // C and C++ allow for main to automagically return 0. 5145 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5146 FD->setHasImplicitReturnZero(true); 5147 WP.disableCheckFallThrough(); 5148 } 5149 5150 if (!FD->isInvalidDecl()) { 5151 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5152 5153 // If this is a constructor, we need a vtable. 5154 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5155 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5156 5157 ComputeNRVO(Body, getCurFunction()); 5158 } 5159 5160 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5161 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5162 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5163 MD->setBody(Body); 5164 MD->setEndLoc(Body->getLocEnd()); 5165 if (!MD->isInvalidDecl()) 5166 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5167 } else { 5168 return 0; 5169 } 5170 5171 // Verify and clean out per-function state. 5172 5173 // Check goto/label use. 5174 FunctionScopeInfo *CurFn = getCurFunction(); 5175 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 5176 I = CurFn->LabelMap.begin(), E = CurFn->LabelMap.end(); I != E; ++I) { 5177 LabelStmt *L = I->second; 5178 5179 // Verify that we have no forward references left. If so, there was a goto 5180 // or address of a label taken, but no definition of it. Label fwd 5181 // definitions are indicated with a null substmt. 5182 if (L->getSubStmt() != 0) { 5183 if (!L->isUsed()) 5184 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 5185 continue; 5186 } 5187 5188 // Emit error. 5189 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 5190 5191 // At this point, we have gotos that use the bogus label. Stitch it into 5192 // the function body so that they aren't leaked and that the AST is well 5193 // formed. 5194 if (Body == 0) { 5195 // The whole function wasn't parsed correctly. 5196 continue; 5197 } 5198 5199 // Otherwise, the body is valid: we want to stitch the label decl into the 5200 // function somewhere so that it is properly owned and so that the goto 5201 // has a valid target. Do this by creating a new compound stmt with the 5202 // label in it. 5203 5204 // Give the label a sub-statement. 5205 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 5206 5207 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 5208 cast<CXXTryStmt>(Body)->getTryBlock() : 5209 cast<CompoundStmt>(Body); 5210 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 5211 Compound->body_end()); 5212 Elements.push_back(L); 5213 Compound->setStmts(Context, Elements.data(), Elements.size()); 5214 } 5215 5216 if (Body) { 5217 // C++ constructors that have function-try-blocks can't have return 5218 // statements in the handlers of that block. (C++ [except.handle]p14) 5219 // Verify this. 5220 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5221 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5222 5223 // Verify that that gotos and switch cases don't jump into scopes illegally. 5224 // Verify that that gotos and switch cases don't jump into scopes illegally. 5225 if (getCurFunction()->NeedsScopeChecking() && 5226 !dcl->isInvalidDecl() && 5227 !hasAnyErrorsInThisFunction()) 5228 DiagnoseInvalidJumps(Body); 5229 5230 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5231 if (!Destructor->getParent()->isDependentType()) 5232 CheckDestructor(Destructor); 5233 5234 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5235 Destructor->getParent()); 5236 } 5237 5238 // If any errors have occurred, clear out any temporaries that may have 5239 // been leftover. This ensures that these temporaries won't be picked up for 5240 // deletion in some later function. 5241 if (PP.getDiagnostics().hasErrorOccurred()) 5242 ExprTemporaries.clear(); 5243 else if (!isa<FunctionTemplateDecl>(dcl)) { 5244 // Since the body is valid, issue any analysis-based warnings that are 5245 // enabled. 5246 QualType ResultType; 5247 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 5248 AnalysisWarnings.IssueWarnings(WP, FD); 5249 } else { 5250 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 5251 AnalysisWarnings.IssueWarnings(WP, MD); 5252 } 5253 } 5254 5255 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5256 } 5257 5258 if (!IsInstantiation) 5259 PopDeclContext(); 5260 5261 PopFunctionOrBlockScope(); 5262 5263 // If any errors have occurred, clear out any temporaries that may have 5264 // been leftover. This ensures that these temporaries won't be picked up for 5265 // deletion in some later function. 5266 if (getDiagnostics().hasErrorOccurred()) 5267 ExprTemporaries.clear(); 5268 5269 return dcl; 5270} 5271 5272/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5273/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5274NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5275 IdentifierInfo &II, Scope *S) { 5276 // Before we produce a declaration for an implicitly defined 5277 // function, see whether there was a locally-scoped declaration of 5278 // this name as a function or variable. If so, use that 5279 // (non-visible) declaration, and complain about it. 5280 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5281 = LocallyScopedExternalDecls.find(&II); 5282 if (Pos != LocallyScopedExternalDecls.end()) { 5283 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5284 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5285 return Pos->second; 5286 } 5287 5288 // Extension in C99. Legal in C90, but warn about it. 5289 if (II.getName().startswith("__builtin_")) 5290 Diag(Loc, diag::warn_builtin_unknown) << &II; 5291 else if (getLangOptions().C99) 5292 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5293 else 5294 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5295 5296 // Set a Declarator for the implicit definition: int foo(); 5297 const char *Dummy; 5298 DeclSpec DS; 5299 unsigned DiagID; 5300 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5301 Error = Error; // Silence warning. 5302 assert(!Error && "Error setting up implicit decl!"); 5303 Declarator D(DS, Declarator::BlockContext); 5304 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5305 0, 0, false, SourceLocation(), 5306 false, 0,0,0, Loc, Loc, D), 5307 SourceLocation()); 5308 D.SetIdentifier(&II, Loc); 5309 5310 // Insert this function into translation-unit scope. 5311 5312 DeclContext *PrevDC = CurContext; 5313 CurContext = Context.getTranslationUnitDecl(); 5314 5315 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5316 FD->setImplicit(); 5317 5318 CurContext = PrevDC; 5319 5320 AddKnownFunctionAttributes(FD); 5321 5322 return FD; 5323} 5324 5325/// \brief Adds any function attributes that we know a priori based on 5326/// the declaration of this function. 5327/// 5328/// These attributes can apply both to implicitly-declared builtins 5329/// (like __builtin___printf_chk) or to library-declared functions 5330/// like NSLog or printf. 5331void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5332 if (FD->isInvalidDecl()) 5333 return; 5334 5335 // If this is a built-in function, map its builtin attributes to 5336 // actual attributes. 5337 if (unsigned BuiltinID = FD->getBuiltinID()) { 5338 // Handle printf-formatting attributes. 5339 unsigned FormatIdx; 5340 bool HasVAListArg; 5341 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5342 if (!FD->getAttr<FormatAttr>()) 5343 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5344 "printf", FormatIdx+1, 5345 HasVAListArg ? 0 : FormatIdx+2)); 5346 } 5347 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5348 HasVAListArg)) { 5349 if (!FD->getAttr<FormatAttr>()) 5350 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5351 "scanf", FormatIdx+1, 5352 HasVAListArg ? 0 : FormatIdx+2)); 5353 } 5354 5355 // Mark const if we don't care about errno and that is the only 5356 // thing preventing the function from being const. This allows 5357 // IRgen to use LLVM intrinsics for such functions. 5358 if (!getLangOptions().MathErrno && 5359 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5360 if (!FD->getAttr<ConstAttr>()) 5361 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5362 } 5363 5364 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5365 FD->setType(Context.getNoReturnType(FD->getType())); 5366 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5367 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5368 if (Context.BuiltinInfo.isConst(BuiltinID)) 5369 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5370 } 5371 5372 IdentifierInfo *Name = FD->getIdentifier(); 5373 if (!Name) 5374 return; 5375 if ((!getLangOptions().CPlusPlus && 5376 FD->getDeclContext()->isTranslationUnit()) || 5377 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5378 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5379 LinkageSpecDecl::lang_c)) { 5380 // Okay: this could be a libc/libm/Objective-C function we know 5381 // about. 5382 } else 5383 return; 5384 5385 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5386 // FIXME: NSLog and NSLogv should be target specific 5387 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5388 // FIXME: We known better than our headers. 5389 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5390 } else 5391 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5392 "printf", 1, 5393 Name->isStr("NSLogv") ? 0 : 2)); 5394 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5395 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5396 // target-specific builtins, perhaps? 5397 if (!FD->getAttr<FormatAttr>()) 5398 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5399 "printf", 2, 5400 Name->isStr("vasprintf") ? 0 : 3)); 5401 } 5402} 5403 5404TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5405 TypeSourceInfo *TInfo) { 5406 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5407 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5408 5409 if (!TInfo) { 5410 assert(D.isInvalidType() && "no declarator info for valid type"); 5411 TInfo = Context.getTrivialTypeSourceInfo(T); 5412 } 5413 5414 // Scope manipulation handled by caller. 5415 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5416 D.getIdentifierLoc(), 5417 D.getIdentifier(), 5418 TInfo); 5419 5420 if (const TagType *TT = T->getAs<TagType>()) { 5421 TagDecl *TD = TT->getDecl(); 5422 5423 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5424 // keep track of the TypedefDecl. 5425 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5426 TD->setTypedefForAnonDecl(NewTD); 5427 } 5428 5429 if (D.isInvalidType()) 5430 NewTD->setInvalidDecl(); 5431 return NewTD; 5432} 5433 5434 5435/// \brief Determine whether a tag with a given kind is acceptable 5436/// as a redeclaration of the given tag declaration. 5437/// 5438/// \returns true if the new tag kind is acceptable, false otherwise. 5439bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5440 TagTypeKind NewTag, 5441 SourceLocation NewTagLoc, 5442 const IdentifierInfo &Name) { 5443 // C++ [dcl.type.elab]p3: 5444 // The class-key or enum keyword present in the 5445 // elaborated-type-specifier shall agree in kind with the 5446 // declaration to which the name in the elaborated-type-specifier 5447 // refers. This rule also applies to the form of 5448 // elaborated-type-specifier that declares a class-name or 5449 // friend class since it can be construed as referring to the 5450 // definition of the class. Thus, in any 5451 // elaborated-type-specifier, the enum keyword shall be used to 5452 // refer to an enumeration (7.2), the union class-key shall be 5453 // used to refer to a union (clause 9), and either the class or 5454 // struct class-key shall be used to refer to a class (clause 9) 5455 // declared using the class or struct class-key. 5456 TagTypeKind OldTag = Previous->getTagKind(); 5457 if (OldTag == NewTag) 5458 return true; 5459 5460 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5461 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5462 // Warn about the struct/class tag mismatch. 5463 bool isTemplate = false; 5464 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5465 isTemplate = Record->getDescribedClassTemplate(); 5466 5467 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5468 << (NewTag == TTK_Class) 5469 << isTemplate << &Name 5470 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5471 OldTag == TTK_Class? "class" : "struct"); 5472 Diag(Previous->getLocation(), diag::note_previous_use); 5473 return true; 5474 } 5475 return false; 5476} 5477 5478/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5479/// former case, Name will be non-null. In the later case, Name will be null. 5480/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5481/// reference/declaration/definition of a tag. 5482Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5483 SourceLocation KWLoc, CXXScopeSpec &SS, 5484 IdentifierInfo *Name, SourceLocation NameLoc, 5485 AttributeList *Attr, AccessSpecifier AS, 5486 MultiTemplateParamsArg TemplateParameterLists, 5487 bool &OwnedDecl, bool &IsDependent, bool ScopedEnum, 5488 TypeResult UnderlyingType) { 5489 // If this is not a definition, it must have a name. 5490 assert((Name != 0 || TUK == TUK_Definition) && 5491 "Nameless record must be a definition!"); 5492 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 5493 5494 OwnedDecl = false; 5495 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5496 5497 // FIXME: Check explicit specializations more carefully. 5498 bool isExplicitSpecialization = false; 5499 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5500 bool Invalid = false; 5501 5502 // We only need to do this matching if we have template parameters 5503 // or a scope specifier, which also conveniently avoids this work 5504 // for non-C++ cases. 5505 if (NumMatchedTemplateParamLists || 5506 (SS.isNotEmpty() && TUK != TUK_Reference)) { 5507 if (TemplateParameterList *TemplateParams 5508 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5509 TemplateParameterLists.get(), 5510 TemplateParameterLists.size(), 5511 TUK == TUK_Friend, 5512 isExplicitSpecialization, 5513 Invalid)) { 5514 // All but one template parameter lists have been matching. 5515 --NumMatchedTemplateParamLists; 5516 5517 if (TemplateParams->size() > 0) { 5518 // This is a declaration or definition of a class template (which may 5519 // be a member of another template). 5520 if (Invalid) 5521 return 0; 5522 5523 OwnedDecl = false; 5524 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5525 SS, Name, NameLoc, Attr, 5526 TemplateParams, 5527 AS); 5528 TemplateParameterLists.release(); 5529 return Result.get(); 5530 } else { 5531 // The "template<>" header is extraneous. 5532 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5533 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5534 isExplicitSpecialization = true; 5535 } 5536 } 5537 } 5538 5539 // Figure out the underlying type if this a enum declaration. We need to do 5540 // this early, because it's needed to detect if this is an incompatible 5541 // redeclaration. 5542 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 5543 5544 if (Kind == TTK_Enum) { 5545 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 5546 // No underlying type explicitly specified, or we failed to parse the 5547 // type, default to int. 5548 EnumUnderlying = Context.IntTy.getTypePtr(); 5549 else if (UnderlyingType.get()) { 5550 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 5551 // integral type; any cv-qualification is ignored. 5552 TypeSourceInfo *TI = 0; 5553 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 5554 EnumUnderlying = TI; 5555 5556 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 5557 5558 if (!T->isDependentType() && !T->isIntegralType(Context)) { 5559 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 5560 << T; 5561 // Recover by falling back to int. 5562 EnumUnderlying = Context.IntTy.getTypePtr(); 5563 } 5564 } else if (getLangOptions().Microsoft) 5565 // Microsoft enums are always of int type. 5566 EnumUnderlying = Context.IntTy.getTypePtr(); 5567 } 5568 5569 DeclContext *SearchDC = CurContext; 5570 DeclContext *DC = CurContext; 5571 bool isStdBadAlloc = false; 5572 5573 RedeclarationKind Redecl = ForRedeclaration; 5574 if (TUK == TUK_Friend || TUK == TUK_Reference) 5575 Redecl = NotForRedeclaration; 5576 5577 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5578 5579 if (Name && SS.isNotEmpty()) { 5580 // We have a nested-name tag ('struct foo::bar'). 5581 5582 // Check for invalid 'foo::'. 5583 if (SS.isInvalid()) { 5584 Name = 0; 5585 goto CreateNewDecl; 5586 } 5587 5588 // If this is a friend or a reference to a class in a dependent 5589 // context, don't try to make a decl for it. 5590 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5591 DC = computeDeclContext(SS, false); 5592 if (!DC) { 5593 IsDependent = true; 5594 return 0; 5595 } 5596 } else { 5597 DC = computeDeclContext(SS, true); 5598 if (!DC) { 5599 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5600 << SS.getRange(); 5601 return 0; 5602 } 5603 } 5604 5605 if (RequireCompleteDeclContext(SS, DC)) 5606 return 0; 5607 5608 SearchDC = DC; 5609 // Look-up name inside 'foo::'. 5610 LookupQualifiedName(Previous, DC); 5611 5612 if (Previous.isAmbiguous()) 5613 return 0; 5614 5615 if (Previous.empty()) { 5616 // Name lookup did not find anything. However, if the 5617 // nested-name-specifier refers to the current instantiation, 5618 // and that current instantiation has any dependent base 5619 // classes, we might find something at instantiation time: treat 5620 // this as a dependent elaborated-type-specifier. 5621 // But this only makes any sense for reference-like lookups. 5622 if (Previous.wasNotFoundInCurrentInstantiation() && 5623 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5624 IsDependent = true; 5625 return 0; 5626 } 5627 5628 // A tag 'foo::bar' must already exist. 5629 Diag(NameLoc, diag::err_not_tag_in_scope) 5630 << Kind << Name << DC << SS.getRange(); 5631 Name = 0; 5632 Invalid = true; 5633 goto CreateNewDecl; 5634 } 5635 } else if (Name) { 5636 // If this is a named struct, check to see if there was a previous forward 5637 // declaration or definition. 5638 // FIXME: We're looking into outer scopes here, even when we 5639 // shouldn't be. Doing so can result in ambiguities that we 5640 // shouldn't be diagnosing. 5641 LookupName(Previous, S); 5642 5643 // Note: there used to be some attempt at recovery here. 5644 if (Previous.isAmbiguous()) 5645 return 0; 5646 5647 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5648 // FIXME: This makes sure that we ignore the contexts associated 5649 // with C structs, unions, and enums when looking for a matching 5650 // tag declaration or definition. See the similar lookup tweak 5651 // in Sema::LookupName; is there a better way to deal with this? 5652 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5653 SearchDC = SearchDC->getParent(); 5654 } 5655 } else if (S->isFunctionPrototypeScope()) { 5656 // If this is an enum declaration in function prototype scope, set its 5657 // initial context to the translation unit. 5658 SearchDC = Context.getTranslationUnitDecl(); 5659 } 5660 5661 if (Previous.isSingleResult() && 5662 Previous.getFoundDecl()->isTemplateParameter()) { 5663 // Maybe we will complain about the shadowed template parameter. 5664 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5665 // Just pretend that we didn't see the previous declaration. 5666 Previous.clear(); 5667 } 5668 5669 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5670 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5671 // This is a declaration of or a reference to "std::bad_alloc". 5672 isStdBadAlloc = true; 5673 5674 if (Previous.empty() && StdBadAlloc) { 5675 // std::bad_alloc has been implicitly declared (but made invisible to 5676 // name lookup). Fill in this implicit declaration as the previous 5677 // declaration, so that the declarations get chained appropriately. 5678 Previous.addDecl(getStdBadAlloc()); 5679 } 5680 } 5681 5682 // If we didn't find a previous declaration, and this is a reference 5683 // (or friend reference), move to the correct scope. In C++, we 5684 // also need to do a redeclaration lookup there, just in case 5685 // there's a shadow friend decl. 5686 if (Name && Previous.empty() && 5687 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5688 if (Invalid) goto CreateNewDecl; 5689 assert(SS.isEmpty()); 5690 5691 if (TUK == TUK_Reference) { 5692 // C++ [basic.scope.pdecl]p5: 5693 // -- for an elaborated-type-specifier of the form 5694 // 5695 // class-key identifier 5696 // 5697 // if the elaborated-type-specifier is used in the 5698 // decl-specifier-seq or parameter-declaration-clause of a 5699 // function defined in namespace scope, the identifier is 5700 // declared as a class-name in the namespace that contains 5701 // the declaration; otherwise, except as a friend 5702 // declaration, the identifier is declared in the smallest 5703 // non-class, non-function-prototype scope that contains the 5704 // declaration. 5705 // 5706 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5707 // C structs and unions. 5708 // 5709 // It is an error in C++ to declare (rather than define) an enum 5710 // type, including via an elaborated type specifier. We'll 5711 // diagnose that later; for now, declare the enum in the same 5712 // scope as we would have picked for any other tag type. 5713 // 5714 // GNU C also supports this behavior as part of its incomplete 5715 // enum types extension, while GNU C++ does not. 5716 // 5717 // Find the context where we'll be declaring the tag. 5718 // FIXME: We would like to maintain the current DeclContext as the 5719 // lexical context, 5720 while (SearchDC->isRecord()) 5721 SearchDC = SearchDC->getParent(); 5722 5723 // Find the scope where we'll be declaring the tag. 5724 while (S->isClassScope() || 5725 (getLangOptions().CPlusPlus && 5726 S->isFunctionPrototypeScope()) || 5727 ((S->getFlags() & Scope::DeclScope) == 0) || 5728 (S->getEntity() && 5729 ((DeclContext *)S->getEntity())->isTransparentContext())) 5730 S = S->getParent(); 5731 } else { 5732 assert(TUK == TUK_Friend); 5733 // C++ [namespace.memdef]p3: 5734 // If a friend declaration in a non-local class first declares a 5735 // class or function, the friend class or function is a member of 5736 // the innermost enclosing namespace. 5737 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5738 } 5739 5740 // In C++, we need to do a redeclaration lookup to properly 5741 // diagnose some problems. 5742 if (getLangOptions().CPlusPlus) { 5743 Previous.setRedeclarationKind(ForRedeclaration); 5744 LookupQualifiedName(Previous, SearchDC); 5745 } 5746 } 5747 5748 if (!Previous.empty()) { 5749 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5750 5751 // It's okay to have a tag decl in the same scope as a typedef 5752 // which hides a tag decl in the same scope. Finding this 5753 // insanity with a redeclaration lookup can only actually happen 5754 // in C++. 5755 // 5756 // This is also okay for elaborated-type-specifiers, which is 5757 // technically forbidden by the current standard but which is 5758 // okay according to the likely resolution of an open issue; 5759 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5760 if (getLangOptions().CPlusPlus) { 5761 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5762 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5763 TagDecl *Tag = TT->getDecl(); 5764 if (Tag->getDeclName() == Name && 5765 Tag->getDeclContext()->getRedeclContext() 5766 ->Equals(TD->getDeclContext()->getRedeclContext())) { 5767 PrevDecl = Tag; 5768 Previous.clear(); 5769 Previous.addDecl(Tag); 5770 Previous.resolveKind(); 5771 } 5772 } 5773 } 5774 } 5775 5776 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5777 // If this is a use of a previous tag, or if the tag is already declared 5778 // in the same scope (so that the definition/declaration completes or 5779 // rementions the tag), reuse the decl. 5780 if (TUK == TUK_Reference || TUK == TUK_Friend || 5781 isDeclInScope(PrevDecl, SearchDC, S)) { 5782 // Make sure that this wasn't declared as an enum and now used as a 5783 // struct or something similar. 5784 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5785 bool SafeToContinue 5786 = (PrevTagDecl->getTagKind() != TTK_Enum && 5787 Kind != TTK_Enum); 5788 if (SafeToContinue) 5789 Diag(KWLoc, diag::err_use_with_wrong_tag) 5790 << Name 5791 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5792 PrevTagDecl->getKindName()); 5793 else 5794 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5795 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5796 5797 if (SafeToContinue) 5798 Kind = PrevTagDecl->getTagKind(); 5799 else { 5800 // Recover by making this an anonymous redefinition. 5801 Name = 0; 5802 Previous.clear(); 5803 Invalid = true; 5804 } 5805 } 5806 5807 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 5808 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 5809 5810 // All conflicts with previous declarations are recovered by 5811 // returning the previous declaration. 5812 if (ScopedEnum != PrevEnum->isScoped()) { 5813 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 5814 << PrevEnum->isScoped(); 5815 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5816 return PrevTagDecl; 5817 } 5818 else if (EnumUnderlying && PrevEnum->isFixed()) { 5819 QualType T; 5820 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 5821 T = TI->getType(); 5822 else 5823 T = QualType(EnumUnderlying.get<const Type*>(), 0); 5824 5825 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 5826 Diag(KWLoc, diag::err_enum_redeclare_type_mismatch); 5827 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5828 return PrevTagDecl; 5829 } 5830 } 5831 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 5832 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 5833 << PrevEnum->isFixed(); 5834 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5835 return PrevTagDecl; 5836 } 5837 } 5838 5839 if (!Invalid) { 5840 // If this is a use, just return the declaration we found. 5841 5842 // FIXME: In the future, return a variant or some other clue 5843 // for the consumer of this Decl to know it doesn't own it. 5844 // For our current ASTs this shouldn't be a problem, but will 5845 // need to be changed with DeclGroups. 5846 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5847 TUK == TUK_Friend) 5848 return PrevTagDecl; 5849 5850 // Diagnose attempts to redefine a tag. 5851 if (TUK == TUK_Definition) { 5852 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5853 // If we're defining a specialization and the previous definition 5854 // is from an implicit instantiation, don't emit an error 5855 // here; we'll catch this in the general case below. 5856 if (!isExplicitSpecialization || 5857 !isa<CXXRecordDecl>(Def) || 5858 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5859 == TSK_ExplicitSpecialization) { 5860 Diag(NameLoc, diag::err_redefinition) << Name; 5861 Diag(Def->getLocation(), diag::note_previous_definition); 5862 // If this is a redefinition, recover by making this 5863 // struct be anonymous, which will make any later 5864 // references get the previous definition. 5865 Name = 0; 5866 Previous.clear(); 5867 Invalid = true; 5868 } 5869 } else { 5870 // If the type is currently being defined, complain 5871 // about a nested redefinition. 5872 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5873 if (Tag->isBeingDefined()) { 5874 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5875 Diag(PrevTagDecl->getLocation(), 5876 diag::note_previous_definition); 5877 Name = 0; 5878 Previous.clear(); 5879 Invalid = true; 5880 } 5881 } 5882 5883 // Okay, this is definition of a previously declared or referenced 5884 // tag PrevDecl. We're going to create a new Decl for it. 5885 } 5886 } 5887 // If we get here we have (another) forward declaration or we 5888 // have a definition. Just create a new decl. 5889 5890 } else { 5891 // If we get here, this is a definition of a new tag type in a nested 5892 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5893 // new decl/type. We set PrevDecl to NULL so that the entities 5894 // have distinct types. 5895 Previous.clear(); 5896 } 5897 // If we get here, we're going to create a new Decl. If PrevDecl 5898 // is non-NULL, it's a definition of the tag declared by 5899 // PrevDecl. If it's NULL, we have a new definition. 5900 5901 5902 // Otherwise, PrevDecl is not a tag, but was found with tag 5903 // lookup. This is only actually possible in C++, where a few 5904 // things like templates still live in the tag namespace. 5905 } else { 5906 assert(getLangOptions().CPlusPlus); 5907 5908 // Use a better diagnostic if an elaborated-type-specifier 5909 // found the wrong kind of type on the first 5910 // (non-redeclaration) lookup. 5911 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5912 !Previous.isForRedeclaration()) { 5913 unsigned Kind = 0; 5914 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5915 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5916 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5917 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5918 Invalid = true; 5919 5920 // Otherwise, only diagnose if the declaration is in scope. 5921 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5922 // do nothing 5923 5924 // Diagnose implicit declarations introduced by elaborated types. 5925 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5926 unsigned Kind = 0; 5927 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5928 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5929 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5930 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5931 Invalid = true; 5932 5933 // Otherwise it's a declaration. Call out a particularly common 5934 // case here. 5935 } else if (isa<TypedefDecl>(PrevDecl)) { 5936 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5937 << Name 5938 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5939 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5940 Invalid = true; 5941 5942 // Otherwise, diagnose. 5943 } else { 5944 // The tag name clashes with something else in the target scope, 5945 // issue an error and recover by making this tag be anonymous. 5946 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5947 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5948 Name = 0; 5949 Invalid = true; 5950 } 5951 5952 // The existing declaration isn't relevant to us; we're in a 5953 // new scope, so clear out the previous declaration. 5954 Previous.clear(); 5955 } 5956 } 5957 5958CreateNewDecl: 5959 5960 TagDecl *PrevDecl = 0; 5961 if (Previous.isSingleResult()) 5962 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5963 5964 // If there is an identifier, use the location of the identifier as the 5965 // location of the decl, otherwise use the location of the struct/union 5966 // keyword. 5967 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5968 5969 // Otherwise, create a new declaration. If there is a previous 5970 // declaration of the same entity, the two will be linked via 5971 // PrevDecl. 5972 TagDecl *New; 5973 5974 bool IsForwardReference = false; 5975 if (Kind == TTK_Enum) { 5976 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5977 // enum X { A, B, C } D; D should chain to X. 5978 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5979 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 5980 !EnumUnderlying.isNull()); 5981 // If this is an undefined enum, warn. 5982 if (TUK != TUK_Definition && !Invalid) { 5983 TagDecl *Def; 5984 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 5985 // C++0x: 7.2p2: opaque-enum-declaration. 5986 // Conflicts are diagnosed above. Do nothing. 5987 } 5988 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5989 Diag(Loc, diag::ext_forward_ref_enum_def) 5990 << New; 5991 Diag(Def->getLocation(), diag::note_previous_definition); 5992 } else { 5993 unsigned DiagID = diag::ext_forward_ref_enum; 5994 if (getLangOptions().Microsoft) 5995 DiagID = diag::ext_ms_forward_ref_enum; 5996 else if (getLangOptions().CPlusPlus) 5997 DiagID = diag::err_forward_ref_enum; 5998 Diag(Loc, DiagID); 5999 6000 // If this is a forward-declared reference to an enumeration, make a 6001 // note of it; we won't actually be introducing the declaration into 6002 // the declaration context. 6003 if (TUK == TUK_Reference) 6004 IsForwardReference = true; 6005 } 6006 } 6007 6008 if (EnumUnderlying) { 6009 EnumDecl *ED = cast<EnumDecl>(New); 6010 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6011 ED->setIntegerTypeSourceInfo(TI); 6012 else 6013 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 6014 ED->setPromotionType(ED->getIntegerType()); 6015 } 6016 6017 } else { 6018 // struct/union/class 6019 6020 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6021 // struct X { int A; } D; D should chain to X. 6022 if (getLangOptions().CPlusPlus) { 6023 // FIXME: Look for a way to use RecordDecl for simple structs. 6024 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 6025 cast_or_null<CXXRecordDecl>(PrevDecl)); 6026 6027 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 6028 StdBadAlloc = cast<CXXRecordDecl>(New); 6029 } else 6030 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 6031 cast_or_null<RecordDecl>(PrevDecl)); 6032 } 6033 6034 // Maybe add qualifier info. 6035 if (SS.isNotEmpty()) { 6036 if (SS.isSet()) { 6037 NestedNameSpecifier *NNS 6038 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 6039 New->setQualifierInfo(NNS, SS.getRange()); 6040 if (NumMatchedTemplateParamLists > 0) { 6041 New->setTemplateParameterListsInfo(Context, 6042 NumMatchedTemplateParamLists, 6043 (TemplateParameterList**) TemplateParameterLists.release()); 6044 } 6045 } 6046 else 6047 Invalid = true; 6048 } 6049 6050 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 6051 // Add alignment attributes if necessary; these attributes are checked when 6052 // the ASTContext lays out the structure. 6053 // 6054 // It is important for implementing the correct semantics that this 6055 // happen here (in act on tag decl). The #pragma pack stack is 6056 // maintained as a result of parser callbacks which can occur at 6057 // many points during the parsing of a struct declaration (because 6058 // the #pragma tokens are effectively skipped over during the 6059 // parsing of the struct). 6060 AddAlignmentAttributesForRecord(RD); 6061 } 6062 6063 // If this is a specialization of a member class (of a class template), 6064 // check the specialization. 6065 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 6066 Invalid = true; 6067 6068 if (Invalid) 6069 New->setInvalidDecl(); 6070 6071 if (Attr) 6072 ProcessDeclAttributeList(S, New, Attr); 6073 6074 // If we're declaring or defining a tag in function prototype scope 6075 // in C, note that this type can only be used within the function. 6076 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6077 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6078 6079 // Set the lexical context. If the tag has a C++ scope specifier, the 6080 // lexical context will be different from the semantic context. 6081 New->setLexicalDeclContext(CurContext); 6082 6083 // Mark this as a friend decl if applicable. 6084 if (TUK == TUK_Friend) 6085 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6086 6087 // Set the access specifier. 6088 if (!Invalid && SearchDC->isRecord()) 6089 SetMemberAccessSpecifier(New, PrevDecl, AS); 6090 6091 if (TUK == TUK_Definition) 6092 New->startDefinition(); 6093 6094 // If this has an identifier, add it to the scope stack. 6095 if (TUK == TUK_Friend) { 6096 // We might be replacing an existing declaration in the lookup tables; 6097 // if so, borrow its access specifier. 6098 if (PrevDecl) 6099 New->setAccess(PrevDecl->getAccess()); 6100 6101 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6102 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6103 if (Name) // can be null along some error paths 6104 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6105 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6106 } else if (Name) { 6107 S = getNonFieldDeclScope(S); 6108 PushOnScopeChains(New, S, !IsForwardReference); 6109 if (IsForwardReference) 6110 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6111 6112 } else { 6113 CurContext->addDecl(New); 6114 } 6115 6116 // If this is the C FILE type, notify the AST context. 6117 if (IdentifierInfo *II = New->getIdentifier()) 6118 if (!New->isInvalidDecl() && 6119 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6120 II->isStr("FILE")) 6121 Context.setFILEDecl(New); 6122 6123 OwnedDecl = true; 6124 return New; 6125} 6126 6127void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6128 AdjustDeclIfTemplate(TagD); 6129 TagDecl *Tag = cast<TagDecl>(TagD); 6130 6131 // Enter the tag context. 6132 PushDeclContext(S, Tag); 6133} 6134 6135void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6136 SourceLocation LBraceLoc) { 6137 AdjustDeclIfTemplate(TagD); 6138 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6139 6140 FieldCollector->StartClass(); 6141 6142 if (!Record->getIdentifier()) 6143 return; 6144 6145 // C++ [class]p2: 6146 // [...] The class-name is also inserted into the scope of the 6147 // class itself; this is known as the injected-class-name. For 6148 // purposes of access checking, the injected-class-name is treated 6149 // as if it were a public member name. 6150 CXXRecordDecl *InjectedClassName 6151 = CXXRecordDecl::Create(Context, Record->getTagKind(), 6152 CurContext, Record->getLocation(), 6153 Record->getIdentifier(), 6154 Record->getTagKeywordLoc(), 6155 /*PrevDecl=*/0, 6156 /*DelayTypeCreation=*/true); 6157 Context.getTypeDeclType(InjectedClassName, Record); 6158 InjectedClassName->setImplicit(); 6159 InjectedClassName->setAccess(AS_public); 6160 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6161 InjectedClassName->setDescribedClassTemplate(Template); 6162 PushOnScopeChains(InjectedClassName, S); 6163 assert(InjectedClassName->isInjectedClassName() && 6164 "Broken injected-class-name"); 6165} 6166 6167void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6168 SourceLocation RBraceLoc) { 6169 AdjustDeclIfTemplate(TagD); 6170 TagDecl *Tag = cast<TagDecl>(TagD); 6171 Tag->setRBraceLoc(RBraceLoc); 6172 6173 if (isa<CXXRecordDecl>(Tag)) 6174 FieldCollector->FinishClass(); 6175 6176 // Exit this scope of this tag's definition. 6177 PopDeclContext(); 6178 6179 // Notify the consumer that we've defined a tag. 6180 Consumer.HandleTagDeclDefinition(Tag); 6181} 6182 6183void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6184 AdjustDeclIfTemplate(TagD); 6185 TagDecl *Tag = cast<TagDecl>(TagD); 6186 Tag->setInvalidDecl(); 6187 6188 // We're undoing ActOnTagStartDefinition here, not 6189 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6190 // the FieldCollector. 6191 6192 PopDeclContext(); 6193} 6194 6195// Note that FieldName may be null for anonymous bitfields. 6196bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6197 QualType FieldTy, const Expr *BitWidth, 6198 bool *ZeroWidth) { 6199 // Default to true; that shouldn't confuse checks for emptiness 6200 if (ZeroWidth) 6201 *ZeroWidth = true; 6202 6203 // C99 6.7.2.1p4 - verify the field type. 6204 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6205 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6206 // Handle incomplete types with specific error. 6207 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6208 return true; 6209 if (FieldName) 6210 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6211 << FieldName << FieldTy << BitWidth->getSourceRange(); 6212 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6213 << FieldTy << BitWidth->getSourceRange(); 6214 } 6215 6216 // If the bit-width is type- or value-dependent, don't try to check 6217 // it now. 6218 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6219 return false; 6220 6221 llvm::APSInt Value; 6222 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6223 return true; 6224 6225 if (Value != 0 && ZeroWidth) 6226 *ZeroWidth = false; 6227 6228 // Zero-width bitfield is ok for anonymous field. 6229 if (Value == 0 && FieldName) 6230 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6231 6232 if (Value.isSigned() && Value.isNegative()) { 6233 if (FieldName) 6234 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6235 << FieldName << Value.toString(10); 6236 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6237 << Value.toString(10); 6238 } 6239 6240 if (!FieldTy->isDependentType()) { 6241 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6242 if (Value.getZExtValue() > TypeSize) { 6243 if (!getLangOptions().CPlusPlus) { 6244 if (FieldName) 6245 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6246 << FieldName << (unsigned)Value.getZExtValue() 6247 << (unsigned)TypeSize; 6248 6249 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6250 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6251 } 6252 6253 if (FieldName) 6254 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6255 << FieldName << (unsigned)Value.getZExtValue() 6256 << (unsigned)TypeSize; 6257 else 6258 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6259 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6260 } 6261 } 6262 6263 return false; 6264} 6265 6266/// ActOnField - Each field of a struct/union/class is passed into this in order 6267/// to create a FieldDecl object for it. 6268Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6269 SourceLocation DeclStart, 6270 Declarator &D, ExprTy *BitfieldWidth) { 6271 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6272 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6273 AS_public); 6274 return Res; 6275} 6276 6277/// HandleField - Analyze a field of a C struct or a C++ data member. 6278/// 6279FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6280 SourceLocation DeclStart, 6281 Declarator &D, Expr *BitWidth, 6282 AccessSpecifier AS) { 6283 IdentifierInfo *II = D.getIdentifier(); 6284 SourceLocation Loc = DeclStart; 6285 if (II) Loc = D.getIdentifierLoc(); 6286 6287 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6288 QualType T = TInfo->getType(); 6289 if (getLangOptions().CPlusPlus) 6290 CheckExtraCXXDefaultArguments(D); 6291 6292 DiagnoseFunctionSpecifiers(D); 6293 6294 if (D.getDeclSpec().isThreadSpecified()) 6295 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6296 6297 // Check to see if this name was declared as a member previously 6298 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6299 LookupName(Previous, S); 6300 assert((Previous.empty() || Previous.isOverloadedResult() || 6301 Previous.isSingleResult()) 6302 && "Lookup of member name should be either overloaded, single or null"); 6303 6304 // If the name is overloaded then get any declaration else get the single result 6305 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6306 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6307 6308 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6309 // Maybe we will complain about the shadowed template parameter. 6310 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6311 // Just pretend that we didn't see the previous declaration. 6312 PrevDecl = 0; 6313 } 6314 6315 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6316 PrevDecl = 0; 6317 6318 bool Mutable 6319 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6320 SourceLocation TSSL = D.getSourceRange().getBegin(); 6321 FieldDecl *NewFD 6322 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6323 AS, PrevDecl, &D); 6324 6325 if (NewFD->isInvalidDecl()) 6326 Record->setInvalidDecl(); 6327 6328 if (NewFD->isInvalidDecl() && PrevDecl) { 6329 // Don't introduce NewFD into scope; there's already something 6330 // with the same name in the same scope. 6331 } else if (II) { 6332 PushOnScopeChains(NewFD, S); 6333 } else 6334 Record->addDecl(NewFD); 6335 6336 return NewFD; 6337} 6338 6339/// \brief Build a new FieldDecl and check its well-formedness. 6340/// 6341/// This routine builds a new FieldDecl given the fields name, type, 6342/// record, etc. \p PrevDecl should refer to any previous declaration 6343/// with the same name and in the same scope as the field to be 6344/// created. 6345/// 6346/// \returns a new FieldDecl. 6347/// 6348/// \todo The Declarator argument is a hack. It will be removed once 6349FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6350 TypeSourceInfo *TInfo, 6351 RecordDecl *Record, SourceLocation Loc, 6352 bool Mutable, Expr *BitWidth, 6353 SourceLocation TSSL, 6354 AccessSpecifier AS, NamedDecl *PrevDecl, 6355 Declarator *D) { 6356 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6357 bool InvalidDecl = false; 6358 if (D) InvalidDecl = D->isInvalidType(); 6359 6360 // If we receive a broken type, recover by assuming 'int' and 6361 // marking this declaration as invalid. 6362 if (T.isNull()) { 6363 InvalidDecl = true; 6364 T = Context.IntTy; 6365 } 6366 6367 QualType EltTy = Context.getBaseElementType(T); 6368 if (!EltTy->isDependentType() && 6369 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6370 // Fields of incomplete type force their record to be invalid. 6371 Record->setInvalidDecl(); 6372 InvalidDecl = true; 6373 } 6374 6375 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6376 // than a variably modified type. 6377 if (!InvalidDecl && T->isVariablyModifiedType()) { 6378 bool SizeIsNegative; 6379 llvm::APSInt Oversized; 6380 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6381 SizeIsNegative, 6382 Oversized); 6383 if (!FixedTy.isNull()) { 6384 Diag(Loc, diag::warn_illegal_constant_array_size); 6385 T = FixedTy; 6386 } else { 6387 if (SizeIsNegative) 6388 Diag(Loc, diag::err_typecheck_negative_array_size); 6389 else if (Oversized.getBoolValue()) 6390 Diag(Loc, diag::err_array_too_large) 6391 << Oversized.toString(10); 6392 else 6393 Diag(Loc, diag::err_typecheck_field_variable_size); 6394 InvalidDecl = true; 6395 } 6396 } 6397 6398 // Fields can not have abstract class types 6399 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6400 diag::err_abstract_type_in_decl, 6401 AbstractFieldType)) 6402 InvalidDecl = true; 6403 6404 bool ZeroWidth = false; 6405 // If this is declared as a bit-field, check the bit-field. 6406 if (!InvalidDecl && BitWidth && 6407 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6408 InvalidDecl = true; 6409 BitWidth = 0; 6410 ZeroWidth = false; 6411 } 6412 6413 // Check that 'mutable' is consistent with the type of the declaration. 6414 if (!InvalidDecl && Mutable) { 6415 unsigned DiagID = 0; 6416 if (T->isReferenceType()) 6417 DiagID = diag::err_mutable_reference; 6418 else if (T.isConstQualified()) 6419 DiagID = diag::err_mutable_const; 6420 6421 if (DiagID) { 6422 SourceLocation ErrLoc = Loc; 6423 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6424 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6425 Diag(ErrLoc, DiagID); 6426 Mutable = false; 6427 InvalidDecl = true; 6428 } 6429 } 6430 6431 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6432 BitWidth, Mutable); 6433 if (InvalidDecl) 6434 NewFD->setInvalidDecl(); 6435 6436 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6437 Diag(Loc, diag::err_duplicate_member) << II; 6438 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6439 NewFD->setInvalidDecl(); 6440 } 6441 6442 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6443 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6444 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6445 if (RDecl->getDefinition()) { 6446 // C++ 9.5p1: An object of a class with a non-trivial 6447 // constructor, a non-trivial copy constructor, a non-trivial 6448 // destructor, or a non-trivial copy assignment operator 6449 // cannot be a member of a union, nor can an array of such 6450 // objects. 6451 // TODO: C++0x alters this restriction significantly. 6452 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6453 NewFD->setInvalidDecl(); 6454 } 6455 } 6456 } 6457 6458 // FIXME: We need to pass in the attributes given an AST 6459 // representation, not a parser representation. 6460 if (D) 6461 // FIXME: What to pass instead of TUScope? 6462 ProcessDeclAttributes(TUScope, NewFD, *D); 6463 6464 if (T.isObjCGCWeak()) 6465 Diag(Loc, diag::warn_attribute_weak_on_field); 6466 6467 NewFD->setAccess(AS); 6468 return NewFD; 6469} 6470 6471bool Sema::CheckNontrivialField(FieldDecl *FD) { 6472 assert(FD); 6473 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6474 6475 if (FD->isInvalidDecl()) 6476 return true; 6477 6478 QualType EltTy = Context.getBaseElementType(FD->getType()); 6479 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6480 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6481 if (RDecl->getDefinition()) { 6482 // We check for copy constructors before constructors 6483 // because otherwise we'll never get complaints about 6484 // copy constructors. 6485 6486 CXXSpecialMember member = CXXInvalid; 6487 if (!RDecl->hasTrivialCopyConstructor()) 6488 member = CXXCopyConstructor; 6489 else if (!RDecl->hasTrivialConstructor()) 6490 member = CXXConstructor; 6491 else if (!RDecl->hasTrivialCopyAssignment()) 6492 member = CXXCopyAssignment; 6493 else if (!RDecl->hasTrivialDestructor()) 6494 member = CXXDestructor; 6495 6496 if (member != CXXInvalid) { 6497 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6498 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6499 DiagnoseNontrivial(RT, member); 6500 return true; 6501 } 6502 } 6503 } 6504 6505 return false; 6506} 6507 6508/// DiagnoseNontrivial - Given that a class has a non-trivial 6509/// special member, figure out why. 6510void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6511 QualType QT(T, 0U); 6512 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6513 6514 // Check whether the member was user-declared. 6515 switch (member) { 6516 case CXXInvalid: 6517 break; 6518 6519 case CXXConstructor: 6520 if (RD->hasUserDeclaredConstructor()) { 6521 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6522 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6523 const FunctionDecl *body = 0; 6524 ci->hasBody(body); 6525 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6526 SourceLocation CtorLoc = ci->getLocation(); 6527 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6528 return; 6529 } 6530 } 6531 6532 assert(0 && "found no user-declared constructors"); 6533 return; 6534 } 6535 break; 6536 6537 case CXXCopyConstructor: 6538 if (RD->hasUserDeclaredCopyConstructor()) { 6539 SourceLocation CtorLoc = 6540 RD->getCopyConstructor(Context, 0)->getLocation(); 6541 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6542 return; 6543 } 6544 break; 6545 6546 case CXXCopyAssignment: 6547 if (RD->hasUserDeclaredCopyAssignment()) { 6548 // FIXME: this should use the location of the copy 6549 // assignment, not the type. 6550 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6551 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6552 return; 6553 } 6554 break; 6555 6556 case CXXDestructor: 6557 if (RD->hasUserDeclaredDestructor()) { 6558 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6559 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6560 return; 6561 } 6562 break; 6563 } 6564 6565 typedef CXXRecordDecl::base_class_iterator base_iter; 6566 6567 // Virtual bases and members inhibit trivial copying/construction, 6568 // but not trivial destruction. 6569 if (member != CXXDestructor) { 6570 // Check for virtual bases. vbases includes indirect virtual bases, 6571 // so we just iterate through the direct bases. 6572 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6573 if (bi->isVirtual()) { 6574 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6575 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6576 return; 6577 } 6578 6579 // Check for virtual methods. 6580 typedef CXXRecordDecl::method_iterator meth_iter; 6581 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6582 ++mi) { 6583 if (mi->isVirtual()) { 6584 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6585 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6586 return; 6587 } 6588 } 6589 } 6590 6591 bool (CXXRecordDecl::*hasTrivial)() const; 6592 switch (member) { 6593 case CXXConstructor: 6594 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6595 case CXXCopyConstructor: 6596 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6597 case CXXCopyAssignment: 6598 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6599 case CXXDestructor: 6600 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6601 default: 6602 assert(0 && "unexpected special member"); return; 6603 } 6604 6605 // Check for nontrivial bases (and recurse). 6606 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6607 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6608 assert(BaseRT && "Don't know how to handle dependent bases"); 6609 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6610 if (!(BaseRecTy->*hasTrivial)()) { 6611 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6612 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6613 DiagnoseNontrivial(BaseRT, member); 6614 return; 6615 } 6616 } 6617 6618 // Check for nontrivial members (and recurse). 6619 typedef RecordDecl::field_iterator field_iter; 6620 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6621 ++fi) { 6622 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6623 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6624 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6625 6626 if (!(EltRD->*hasTrivial)()) { 6627 SourceLocation FLoc = (*fi)->getLocation(); 6628 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6629 DiagnoseNontrivial(EltRT, member); 6630 return; 6631 } 6632 } 6633 } 6634 6635 assert(0 && "found no explanation for non-trivial member"); 6636} 6637 6638/// TranslateIvarVisibility - Translate visibility from a token ID to an 6639/// AST enum value. 6640static ObjCIvarDecl::AccessControl 6641TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6642 switch (ivarVisibility) { 6643 default: assert(0 && "Unknown visitibility kind"); 6644 case tok::objc_private: return ObjCIvarDecl::Private; 6645 case tok::objc_public: return ObjCIvarDecl::Public; 6646 case tok::objc_protected: return ObjCIvarDecl::Protected; 6647 case tok::objc_package: return ObjCIvarDecl::Package; 6648 } 6649} 6650 6651/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6652/// in order to create an IvarDecl object for it. 6653Decl *Sema::ActOnIvar(Scope *S, 6654 SourceLocation DeclStart, 6655 Decl *IntfDecl, 6656 Declarator &D, ExprTy *BitfieldWidth, 6657 tok::ObjCKeywordKind Visibility) { 6658 6659 IdentifierInfo *II = D.getIdentifier(); 6660 Expr *BitWidth = (Expr*)BitfieldWidth; 6661 SourceLocation Loc = DeclStart; 6662 if (II) Loc = D.getIdentifierLoc(); 6663 6664 // FIXME: Unnamed fields can be handled in various different ways, for 6665 // example, unnamed unions inject all members into the struct namespace! 6666 6667 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6668 QualType T = TInfo->getType(); 6669 6670 if (BitWidth) { 6671 // 6.7.2.1p3, 6.7.2.1p4 6672 if (VerifyBitField(Loc, II, T, BitWidth)) { 6673 D.setInvalidType(); 6674 BitWidth = 0; 6675 } 6676 } else { 6677 // Not a bitfield. 6678 6679 // validate II. 6680 6681 } 6682 if (T->isReferenceType()) { 6683 Diag(Loc, diag::err_ivar_reference_type); 6684 D.setInvalidType(); 6685 } 6686 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6687 // than a variably modified type. 6688 else if (T->isVariablyModifiedType()) { 6689 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6690 D.setInvalidType(); 6691 } 6692 6693 // Get the visibility (access control) for this ivar. 6694 ObjCIvarDecl::AccessControl ac = 6695 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6696 : ObjCIvarDecl::None; 6697 // Must set ivar's DeclContext to its enclosing interface. 6698 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6699 ObjCContainerDecl *EnclosingContext; 6700 if (ObjCImplementationDecl *IMPDecl = 6701 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6702 if (!LangOpts.ObjCNonFragileABI2) { 6703 // Case of ivar declared in an implementation. Context is that of its class. 6704 EnclosingContext = IMPDecl->getClassInterface(); 6705 assert(EnclosingContext && "Implementation has no class interface!"); 6706 } 6707 else 6708 EnclosingContext = EnclosingDecl; 6709 } else { 6710 if (ObjCCategoryDecl *CDecl = 6711 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6712 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6713 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6714 return 0; 6715 } 6716 } 6717 EnclosingContext = EnclosingDecl; 6718 } 6719 6720 // Construct the decl. 6721 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6722 EnclosingContext, Loc, II, T, 6723 TInfo, ac, (Expr *)BitfieldWidth); 6724 6725 if (II) { 6726 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6727 ForRedeclaration); 6728 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6729 && !isa<TagDecl>(PrevDecl)) { 6730 Diag(Loc, diag::err_duplicate_member) << II; 6731 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6732 NewID->setInvalidDecl(); 6733 } 6734 } 6735 6736 // Process attributes attached to the ivar. 6737 ProcessDeclAttributes(S, NewID, D); 6738 6739 if (D.isInvalidType()) 6740 NewID->setInvalidDecl(); 6741 6742 if (II) { 6743 // FIXME: When interfaces are DeclContexts, we'll need to add 6744 // these to the interface. 6745 S->AddDecl(NewID); 6746 IdResolver.AddDecl(NewID); 6747 } 6748 6749 return NewID; 6750} 6751 6752/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6753/// class and class extensions. For every class @interface and class 6754/// extension @interface, if the last ivar is a bitfield of any type, 6755/// then add an implicit `char :0` ivar to the end of that interface. 6756void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6757 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6758 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6759 return; 6760 6761 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6762 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6763 6764 if (!Ivar->isBitField()) 6765 return; 6766 uint64_t BitFieldSize = 6767 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6768 if (BitFieldSize == 0) 6769 return; 6770 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6771 if (!ID) { 6772 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6773 if (!CD->IsClassExtension()) 6774 return; 6775 } 6776 // No need to add this to end of @implementation. 6777 else 6778 return; 6779 } 6780 // All conditions are met. Add a new bitfield to the tail end of ivars. 6781 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6782 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 6783 6784 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6785 DeclLoc, 0, 6786 Context.CharTy, 6787 Context.CreateTypeSourceInfo(Context.CharTy), 6788 ObjCIvarDecl::Private, BW, 6789 true); 6790 AllIvarDecls.push_back(Ivar); 6791} 6792 6793void Sema::ActOnFields(Scope* S, 6794 SourceLocation RecLoc, Decl *EnclosingDecl, 6795 Decl **Fields, unsigned NumFields, 6796 SourceLocation LBrac, SourceLocation RBrac, 6797 AttributeList *Attr) { 6798 assert(EnclosingDecl && "missing record or interface decl"); 6799 6800 // If the decl this is being inserted into is invalid, then it may be a 6801 // redeclaration or some other bogus case. Don't try to add fields to it. 6802 if (EnclosingDecl->isInvalidDecl()) { 6803 // FIXME: Deallocate fields? 6804 return; 6805 } 6806 6807 6808 // Verify that all the fields are okay. 6809 unsigned NumNamedMembers = 0; 6810 llvm::SmallVector<FieldDecl*, 32> RecFields; 6811 6812 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6813 for (unsigned i = 0; i != NumFields; ++i) { 6814 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6815 6816 // Get the type for the field. 6817 Type *FDTy = FD->getType().getTypePtr(); 6818 6819 if (!FD->isAnonymousStructOrUnion()) { 6820 // Remember all fields written by the user. 6821 RecFields.push_back(FD); 6822 } 6823 6824 // If the field is already invalid for some reason, don't emit more 6825 // diagnostics about it. 6826 if (FD->isInvalidDecl()) { 6827 EnclosingDecl->setInvalidDecl(); 6828 continue; 6829 } 6830 6831 // C99 6.7.2.1p2: 6832 // A structure or union shall not contain a member with 6833 // incomplete or function type (hence, a structure shall not 6834 // contain an instance of itself, but may contain a pointer to 6835 // an instance of itself), except that the last member of a 6836 // structure with more than one named member may have incomplete 6837 // array type; such a structure (and any union containing, 6838 // possibly recursively, a member that is such a structure) 6839 // shall not be a member of a structure or an element of an 6840 // array. 6841 if (FDTy->isFunctionType()) { 6842 // Field declared as a function. 6843 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6844 << FD->getDeclName(); 6845 FD->setInvalidDecl(); 6846 EnclosingDecl->setInvalidDecl(); 6847 continue; 6848 } else if (FDTy->isIncompleteArrayType() && Record && 6849 ((i == NumFields - 1 && !Record->isUnion()) || 6850 (getLangOptions().Microsoft && 6851 (i == NumFields - 1 || Record->isUnion())))) { 6852 // Flexible array member. 6853 // Microsoft is more permissive regarding flexible array. 6854 // It will accept flexible array in union and also 6855 // as the sole element of a struct/class. 6856 if (getLangOptions().Microsoft) { 6857 if (Record->isUnion()) 6858 Diag(FD->getLocation(), diag::ext_flexible_array_union) 6859 << FD->getDeclName(); 6860 else if (NumFields == 1) 6861 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 6862 << FD->getDeclName() << Record->getTagKind(); 6863 } else if (NumNamedMembers < 1) { 6864 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6865 << FD->getDeclName(); 6866 FD->setInvalidDecl(); 6867 EnclosingDecl->setInvalidDecl(); 6868 continue; 6869 } 6870 if (!FD->getType()->isDependentType() && 6871 !Context.getBaseElementType(FD->getType())->isPODType()) { 6872 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6873 << FD->getDeclName() << FD->getType(); 6874 FD->setInvalidDecl(); 6875 EnclosingDecl->setInvalidDecl(); 6876 continue; 6877 } 6878 // Okay, we have a legal flexible array member at the end of the struct. 6879 if (Record) 6880 Record->setHasFlexibleArrayMember(true); 6881 } else if (!FDTy->isDependentType() && 6882 RequireCompleteType(FD->getLocation(), FD->getType(), 6883 diag::err_field_incomplete)) { 6884 // Incomplete type 6885 FD->setInvalidDecl(); 6886 EnclosingDecl->setInvalidDecl(); 6887 continue; 6888 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6889 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6890 // If this is a member of a union, then entire union becomes "flexible". 6891 if (Record && Record->isUnion()) { 6892 Record->setHasFlexibleArrayMember(true); 6893 } else { 6894 // If this is a struct/class and this is not the last element, reject 6895 // it. Note that GCC supports variable sized arrays in the middle of 6896 // structures. 6897 if (i != NumFields-1) 6898 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6899 << FD->getDeclName() << FD->getType(); 6900 else { 6901 // We support flexible arrays at the end of structs in 6902 // other structs as an extension. 6903 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6904 << FD->getDeclName(); 6905 if (Record) 6906 Record->setHasFlexibleArrayMember(true); 6907 } 6908 } 6909 } 6910 if (Record && FDTTy->getDecl()->hasObjectMember()) 6911 Record->setHasObjectMember(true); 6912 } else if (FDTy->isObjCObjectType()) { 6913 /// A field cannot be an Objective-c object 6914 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6915 FD->setInvalidDecl(); 6916 EnclosingDecl->setInvalidDecl(); 6917 continue; 6918 } else if (getLangOptions().ObjC1 && 6919 getLangOptions().getGCMode() != LangOptions::NonGC && 6920 Record && 6921 (FD->getType()->isObjCObjectPointerType() || 6922 FD->getType().isObjCGCStrong())) 6923 Record->setHasObjectMember(true); 6924 else if (Context.getAsArrayType(FD->getType())) { 6925 QualType BaseType = Context.getBaseElementType(FD->getType()); 6926 if (Record && BaseType->isRecordType() && 6927 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6928 Record->setHasObjectMember(true); 6929 } 6930 // Keep track of the number of named members. 6931 if (FD->getIdentifier()) 6932 ++NumNamedMembers; 6933 } 6934 6935 // Okay, we successfully defined 'Record'. 6936 if (Record) { 6937 bool Completed = false; 6938 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 6939 if (!CXXRecord->isInvalidDecl()) { 6940 // Set access bits correctly on the directly-declared conversions. 6941 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 6942 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 6943 I != E; ++I) 6944 Convs->setAccess(I, (*I)->getAccess()); 6945 6946 if (!CXXRecord->isDependentType()) { 6947 // Add any implicitly-declared members to this class. 6948 AddImplicitlyDeclaredMembersToClass(CXXRecord); 6949 6950 // If we have virtual base classes, we may end up finding multiple 6951 // final overriders for a given virtual function. Check for this 6952 // problem now. 6953 if (CXXRecord->getNumVBases()) { 6954 CXXFinalOverriderMap FinalOverriders; 6955 CXXRecord->getFinalOverriders(FinalOverriders); 6956 6957 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 6958 MEnd = FinalOverriders.end(); 6959 M != MEnd; ++M) { 6960 for (OverridingMethods::iterator SO = M->second.begin(), 6961 SOEnd = M->second.end(); 6962 SO != SOEnd; ++SO) { 6963 assert(SO->second.size() > 0 && 6964 "Virtual function without overridding functions?"); 6965 if (SO->second.size() == 1) 6966 continue; 6967 6968 // C++ [class.virtual]p2: 6969 // In a derived class, if a virtual member function of a base 6970 // class subobject has more than one final overrider the 6971 // program is ill-formed. 6972 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 6973 << (NamedDecl *)M->first << Record; 6974 Diag(M->first->getLocation(), 6975 diag::note_overridden_virtual_function); 6976 for (OverridingMethods::overriding_iterator 6977 OM = SO->second.begin(), 6978 OMEnd = SO->second.end(); 6979 OM != OMEnd; ++OM) 6980 Diag(OM->Method->getLocation(), diag::note_final_overrider) 6981 << (NamedDecl *)M->first << OM->Method->getParent(); 6982 6983 Record->setInvalidDecl(); 6984 } 6985 } 6986 CXXRecord->completeDefinition(&FinalOverriders); 6987 Completed = true; 6988 } 6989 } 6990 } 6991 } 6992 6993 if (!Completed) 6994 Record->completeDefinition(); 6995 } else { 6996 ObjCIvarDecl **ClsFields = 6997 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6998 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6999 ID->setLocEnd(RBrac); 7000 // Add ivar's to class's DeclContext. 7001 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7002 ClsFields[i]->setLexicalDeclContext(ID); 7003 ID->addDecl(ClsFields[i]); 7004 } 7005 // Must enforce the rule that ivars in the base classes may not be 7006 // duplicates. 7007 if (ID->getSuperClass()) 7008 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 7009 } else if (ObjCImplementationDecl *IMPDecl = 7010 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7011 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 7012 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 7013 // Ivar declared in @implementation never belongs to the implementation. 7014 // Only it is in implementation's lexical context. 7015 ClsFields[I]->setLexicalDeclContext(IMPDecl); 7016 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 7017 } else if (ObjCCategoryDecl *CDecl = 7018 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7019 // case of ivars in class extension; all other cases have been 7020 // reported as errors elsewhere. 7021 // FIXME. Class extension does not have a LocEnd field. 7022 // CDecl->setLocEnd(RBrac); 7023 // Add ivar's to class extension's DeclContext. 7024 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7025 ClsFields[i]->setLexicalDeclContext(CDecl); 7026 CDecl->addDecl(ClsFields[i]); 7027 } 7028 } 7029 } 7030 7031 if (Attr) 7032 ProcessDeclAttributeList(S, Record, Attr); 7033 7034 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 7035 // set the visibility of this record. 7036 if (Record && !Record->getDeclContext()->isRecord()) 7037 AddPushedVisibilityAttribute(Record); 7038} 7039 7040/// \brief Determine whether the given integral value is representable within 7041/// the given type T. 7042static bool isRepresentableIntegerValue(ASTContext &Context, 7043 llvm::APSInt &Value, 7044 QualType T) { 7045 assert(T->isIntegralType(Context) && "Integral type required!"); 7046 unsigned BitWidth = Context.getIntWidth(T); 7047 7048 if (Value.isUnsigned() || Value.isNonNegative()) { 7049 if (T->isSignedIntegerType()) 7050 --BitWidth; 7051 return Value.getActiveBits() <= BitWidth; 7052 } 7053 return Value.getMinSignedBits() <= BitWidth; 7054} 7055 7056// \brief Given an integral type, return the next larger integral type 7057// (or a NULL type of no such type exists). 7058static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 7059 // FIXME: Int128/UInt128 support, which also needs to be introduced into 7060 // enum checking below. 7061 assert(T->isIntegralType(Context) && "Integral type required!"); 7062 const unsigned NumTypes = 4; 7063 QualType SignedIntegralTypes[NumTypes] = { 7064 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 7065 }; 7066 QualType UnsignedIntegralTypes[NumTypes] = { 7067 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 7068 Context.UnsignedLongLongTy 7069 }; 7070 7071 unsigned BitWidth = Context.getTypeSize(T); 7072 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7073 : UnsignedIntegralTypes; 7074 for (unsigned I = 0; I != NumTypes; ++I) 7075 if (Context.getTypeSize(Types[I]) > BitWidth) 7076 return Types[I]; 7077 7078 return QualType(); 7079} 7080 7081EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7082 EnumConstantDecl *LastEnumConst, 7083 SourceLocation IdLoc, 7084 IdentifierInfo *Id, 7085 Expr *Val) { 7086 unsigned IntWidth = Context.Target.getIntWidth(); 7087 llvm::APSInt EnumVal(IntWidth); 7088 QualType EltTy; 7089 if (Val) { 7090 if (Enum->isDependentType() || Val->isTypeDependent()) 7091 EltTy = Context.DependentTy; 7092 else { 7093 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7094 SourceLocation ExpLoc; 7095 if (!Val->isValueDependent() && 7096 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7097 Val = 0; 7098 } else { 7099 if (!getLangOptions().CPlusPlus) { 7100 // C99 6.7.2.2p2: 7101 // The expression that defines the value of an enumeration constant 7102 // shall be an integer constant expression that has a value 7103 // representable as an int. 7104 7105 // Complain if the value is not representable in an int. 7106 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7107 Diag(IdLoc, diag::ext_enum_value_not_int) 7108 << EnumVal.toString(10) << Val->getSourceRange() 7109 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7110 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7111 // Force the type of the expression to 'int'. 7112 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 7113 } 7114 } 7115 7116 if (Enum->isFixed()) { 7117 EltTy = Enum->getIntegerType(); 7118 7119 // C++0x [dcl.enum]p5: 7120 // ... if the initializing value of an enumerator cannot be 7121 // represented by the underlying type, the program is ill-formed. 7122 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7123 if (getLangOptions().Microsoft) { 7124 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 7125 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7126 } else 7127 Diag(IdLoc, diag::err_enumerator_too_large) 7128 << EltTy; 7129 } else 7130 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7131 } 7132 else { 7133 // C++0x [dcl.enum]p5: 7134 // If the underlying type is not fixed, the type of each enumerator 7135 // is the type of its initializing value: 7136 // - If an initializer is specified for an enumerator, the 7137 // initializing value has the same type as the expression. 7138 EltTy = Val->getType(); 7139 } 7140 } 7141 } 7142 } 7143 7144 if (!Val) { 7145 if (Enum->isDependentType()) 7146 EltTy = Context.DependentTy; 7147 else if (!LastEnumConst) { 7148 // C++0x [dcl.enum]p5: 7149 // If the underlying type is not fixed, the type of each enumerator 7150 // is the type of its initializing value: 7151 // - If no initializer is specified for the first enumerator, the 7152 // initializing value has an unspecified integral type. 7153 // 7154 // GCC uses 'int' for its unspecified integral type, as does 7155 // C99 6.7.2.2p3. 7156 if (Enum->isFixed()) { 7157 EltTy = Enum->getIntegerType(); 7158 } 7159 else { 7160 EltTy = Context.IntTy; 7161 } 7162 } else { 7163 // Assign the last value + 1. 7164 EnumVal = LastEnumConst->getInitVal(); 7165 ++EnumVal; 7166 EltTy = LastEnumConst->getType(); 7167 7168 // Check for overflow on increment. 7169 if (EnumVal < LastEnumConst->getInitVal()) { 7170 // C++0x [dcl.enum]p5: 7171 // If the underlying type is not fixed, the type of each enumerator 7172 // is the type of its initializing value: 7173 // 7174 // - Otherwise the type of the initializing value is the same as 7175 // the type of the initializing value of the preceding enumerator 7176 // unless the incremented value is not representable in that type, 7177 // in which case the type is an unspecified integral type 7178 // sufficient to contain the incremented value. If no such type 7179 // exists, the program is ill-formed. 7180 QualType T = getNextLargerIntegralType(Context, EltTy); 7181 if (T.isNull() || Enum->isFixed()) { 7182 // There is no integral type larger enough to represent this 7183 // value. Complain, then allow the value to wrap around. 7184 EnumVal = LastEnumConst->getInitVal(); 7185 EnumVal.zext(EnumVal.getBitWidth() * 2); 7186 ++EnumVal; 7187 if (Enum->isFixed()) 7188 // When the underlying type is fixed, this is ill-formed. 7189 Diag(IdLoc, diag::err_enumerator_wrapped) 7190 << EnumVal.toString(10) 7191 << EltTy; 7192 else 7193 Diag(IdLoc, diag::warn_enumerator_too_large) 7194 << EnumVal.toString(10); 7195 } else { 7196 EltTy = T; 7197 } 7198 7199 // Retrieve the last enumerator's value, extent that type to the 7200 // type that is supposed to be large enough to represent the incremented 7201 // value, then increment. 7202 EnumVal = LastEnumConst->getInitVal(); 7203 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7204 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7205 ++EnumVal; 7206 7207 // If we're not in C++, diagnose the overflow of enumerator values, 7208 // which in C99 means that the enumerator value is not representable in 7209 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7210 // permits enumerator values that are representable in some larger 7211 // integral type. 7212 if (!getLangOptions().CPlusPlus && !T.isNull()) 7213 Diag(IdLoc, diag::warn_enum_value_overflow); 7214 } else if (!getLangOptions().CPlusPlus && 7215 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7216 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7217 Diag(IdLoc, diag::ext_enum_value_not_int) 7218 << EnumVal.toString(10) << 1; 7219 } 7220 } 7221 } 7222 7223 if (!EltTy->isDependentType()) { 7224 // Make the enumerator value match the signedness and size of the 7225 // enumerator's type. 7226 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7227 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7228 } 7229 7230 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7231 Val, EnumVal); 7232} 7233 7234 7235Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 7236 SourceLocation IdLoc, IdentifierInfo *Id, 7237 AttributeList *Attr, 7238 SourceLocation EqualLoc, ExprTy *val) { 7239 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7240 EnumConstantDecl *LastEnumConst = 7241 cast_or_null<EnumConstantDecl>(lastEnumConst); 7242 Expr *Val = static_cast<Expr*>(val); 7243 7244 // The scope passed in may not be a decl scope. Zip up the scope tree until 7245 // we find one that is. 7246 S = getNonFieldDeclScope(S); 7247 7248 // Verify that there isn't already something declared with this name in this 7249 // scope. 7250 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7251 ForRedeclaration); 7252 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7253 // Maybe we will complain about the shadowed template parameter. 7254 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7255 // Just pretend that we didn't see the previous declaration. 7256 PrevDecl = 0; 7257 } 7258 7259 if (PrevDecl) { 7260 // When in C++, we may get a TagDecl with the same name; in this case the 7261 // enum constant will 'hide' the tag. 7262 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7263 "Received TagDecl when not in C++!"); 7264 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7265 if (isa<EnumConstantDecl>(PrevDecl)) 7266 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7267 else 7268 Diag(IdLoc, diag::err_redefinition) << Id; 7269 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7270 return 0; 7271 } 7272 } 7273 7274 // C++ [class.mem]p13: 7275 // If T is the name of a class, then each of the following shall have a 7276 // name different from T: 7277 // - every enumerator of every member of class T that is an enumerated 7278 // type 7279 if (CXXRecordDecl *Record 7280 = dyn_cast<CXXRecordDecl>( 7281 TheEnumDecl->getDeclContext()->getRedeclContext())) 7282 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7283 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7284 7285 EnumConstantDecl *New = 7286 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 7287 7288 if (New) { 7289 // Process attributes. 7290 if (Attr) ProcessDeclAttributeList(S, New, Attr); 7291 7292 // Register this decl in the current scope stack. 7293 New->setAccess(TheEnumDecl->getAccess()); 7294 PushOnScopeChains(New, S); 7295 } 7296 7297 return New; 7298} 7299 7300void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7301 SourceLocation RBraceLoc, Decl *EnumDeclX, 7302 Decl **Elements, unsigned NumElements, 7303 Scope *S, AttributeList *Attr) { 7304 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7305 QualType EnumType = Context.getTypeDeclType(Enum); 7306 7307 if (Attr) 7308 ProcessDeclAttributeList(S, Enum, Attr); 7309 7310 if (Enum->isDependentType()) { 7311 for (unsigned i = 0; i != NumElements; ++i) { 7312 EnumConstantDecl *ECD = 7313 cast_or_null<EnumConstantDecl>(Elements[i]); 7314 if (!ECD) continue; 7315 7316 ECD->setType(EnumType); 7317 } 7318 7319 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7320 return; 7321 } 7322 7323 // TODO: If the result value doesn't fit in an int, it must be a long or long 7324 // long value. ISO C does not support this, but GCC does as an extension, 7325 // emit a warning. 7326 unsigned IntWidth = Context.Target.getIntWidth(); 7327 unsigned CharWidth = Context.Target.getCharWidth(); 7328 unsigned ShortWidth = Context.Target.getShortWidth(); 7329 7330 // Verify that all the values are okay, compute the size of the values, and 7331 // reverse the list. 7332 unsigned NumNegativeBits = 0; 7333 unsigned NumPositiveBits = 0; 7334 7335 // Keep track of whether all elements have type int. 7336 bool AllElementsInt = true; 7337 7338 for (unsigned i = 0; i != NumElements; ++i) { 7339 EnumConstantDecl *ECD = 7340 cast_or_null<EnumConstantDecl>(Elements[i]); 7341 if (!ECD) continue; // Already issued a diagnostic. 7342 7343 const llvm::APSInt &InitVal = ECD->getInitVal(); 7344 7345 // Keep track of the size of positive and negative values. 7346 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7347 NumPositiveBits = std::max(NumPositiveBits, 7348 (unsigned)InitVal.getActiveBits()); 7349 else 7350 NumNegativeBits = std::max(NumNegativeBits, 7351 (unsigned)InitVal.getMinSignedBits()); 7352 7353 // Keep track of whether every enum element has type int (very commmon). 7354 if (AllElementsInt) 7355 AllElementsInt = ECD->getType() == Context.IntTy; 7356 } 7357 7358 // Figure out the type that should be used for this enum. 7359 // FIXME: Support -fshort-enums. 7360 QualType BestType; 7361 unsigned BestWidth; 7362 7363 // C++0x N3000 [conv.prom]p3: 7364 // An rvalue of an unscoped enumeration type whose underlying 7365 // type is not fixed can be converted to an rvalue of the first 7366 // of the following types that can represent all the values of 7367 // the enumeration: int, unsigned int, long int, unsigned long 7368 // int, long long int, or unsigned long long int. 7369 // C99 6.4.4.3p2: 7370 // An identifier declared as an enumeration constant has type int. 7371 // The C99 rule is modified by a gcc extension 7372 QualType BestPromotionType; 7373 7374 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7375 // -fshort-enums is the equivalent to specifying the packed attribute on all 7376 // enum definitions. 7377 if (LangOpts.ShortEnums) 7378 Packed = true; 7379 7380 if (Enum->isFixed()) { 7381 BestType = BestPromotionType = Enum->getIntegerType(); 7382 // We don't need to set BestWidth, because BestType is going to be the type 7383 // of the enumerators, but we do anyway because otherwise some compilers 7384 // warn that it might be used uninitialized. 7385 BestWidth = CharWidth; 7386 } 7387 else if (NumNegativeBits) { 7388 // If there is a negative value, figure out the smallest integer type (of 7389 // int/long/longlong) that fits. 7390 // If it's packed, check also if it fits a char or a short. 7391 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7392 BestType = Context.SignedCharTy; 7393 BestWidth = CharWidth; 7394 } else if (Packed && NumNegativeBits <= ShortWidth && 7395 NumPositiveBits < ShortWidth) { 7396 BestType = Context.ShortTy; 7397 BestWidth = ShortWidth; 7398 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7399 BestType = Context.IntTy; 7400 BestWidth = IntWidth; 7401 } else { 7402 BestWidth = Context.Target.getLongWidth(); 7403 7404 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7405 BestType = Context.LongTy; 7406 } else { 7407 BestWidth = Context.Target.getLongLongWidth(); 7408 7409 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7410 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7411 BestType = Context.LongLongTy; 7412 } 7413 } 7414 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7415 } else { 7416 // If there is no negative value, figure out the smallest type that fits 7417 // all of the enumerator values. 7418 // If it's packed, check also if it fits a char or a short. 7419 if (Packed && NumPositiveBits <= CharWidth) { 7420 BestType = Context.UnsignedCharTy; 7421 BestPromotionType = Context.IntTy; 7422 BestWidth = CharWidth; 7423 } else if (Packed && NumPositiveBits <= ShortWidth) { 7424 BestType = Context.UnsignedShortTy; 7425 BestPromotionType = Context.IntTy; 7426 BestWidth = ShortWidth; 7427 } else if (NumPositiveBits <= IntWidth) { 7428 BestType = Context.UnsignedIntTy; 7429 BestWidth = IntWidth; 7430 BestPromotionType 7431 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7432 ? Context.UnsignedIntTy : Context.IntTy; 7433 } else if (NumPositiveBits <= 7434 (BestWidth = Context.Target.getLongWidth())) { 7435 BestType = Context.UnsignedLongTy; 7436 BestPromotionType 7437 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7438 ? Context.UnsignedLongTy : Context.LongTy; 7439 } else { 7440 BestWidth = Context.Target.getLongLongWidth(); 7441 assert(NumPositiveBits <= BestWidth && 7442 "How could an initializer get larger than ULL?"); 7443 BestType = Context.UnsignedLongLongTy; 7444 BestPromotionType 7445 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7446 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7447 } 7448 } 7449 7450 // Loop over all of the enumerator constants, changing their types to match 7451 // the type of the enum if needed. 7452 for (unsigned i = 0; i != NumElements; ++i) { 7453 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7454 if (!ECD) continue; // Already issued a diagnostic. 7455 7456 // Standard C says the enumerators have int type, but we allow, as an 7457 // extension, the enumerators to be larger than int size. If each 7458 // enumerator value fits in an int, type it as an int, otherwise type it the 7459 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7460 // that X has type 'int', not 'unsigned'. 7461 7462 // Determine whether the value fits into an int. 7463 llvm::APSInt InitVal = ECD->getInitVal(); 7464 7465 // If it fits into an integer type, force it. Otherwise force it to match 7466 // the enum decl type. 7467 QualType NewTy; 7468 unsigned NewWidth; 7469 bool NewSign; 7470 if (!getLangOptions().CPlusPlus && 7471 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7472 NewTy = Context.IntTy; 7473 NewWidth = IntWidth; 7474 NewSign = true; 7475 } else if (ECD->getType() == BestType) { 7476 // Already the right type! 7477 if (getLangOptions().CPlusPlus) 7478 // C++ [dcl.enum]p4: Following the closing brace of an 7479 // enum-specifier, each enumerator has the type of its 7480 // enumeration. 7481 ECD->setType(EnumType); 7482 continue; 7483 } else { 7484 NewTy = BestType; 7485 NewWidth = BestWidth; 7486 NewSign = BestType->isSignedIntegerType(); 7487 } 7488 7489 // Adjust the APSInt value. 7490 InitVal.extOrTrunc(NewWidth); 7491 InitVal.setIsSigned(NewSign); 7492 ECD->setInitVal(InitVal); 7493 7494 // Adjust the Expr initializer and type. 7495 if (ECD->getInitExpr()) 7496 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7497 CK_IntegralCast, 7498 ECD->getInitExpr(), 7499 /*base paths*/ 0, 7500 VK_RValue)); 7501 if (getLangOptions().CPlusPlus) 7502 // C++ [dcl.enum]p4: Following the closing brace of an 7503 // enum-specifier, each enumerator has the type of its 7504 // enumeration. 7505 ECD->setType(EnumType); 7506 else 7507 ECD->setType(NewTy); 7508 } 7509 7510 Enum->completeDefinition(BestType, BestPromotionType, 7511 NumPositiveBits, NumNegativeBits); 7512} 7513 7514Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7515 StringLiteral *AsmString = cast<StringLiteral>(expr); 7516 7517 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7518 Loc, AsmString); 7519 CurContext->addDecl(New); 7520 return New; 7521} 7522 7523void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7524 SourceLocation PragmaLoc, 7525 SourceLocation NameLoc) { 7526 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7527 7528 if (PrevDecl) { 7529 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7530 } else { 7531 (void)WeakUndeclaredIdentifiers.insert( 7532 std::pair<IdentifierInfo*,WeakInfo> 7533 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7534 } 7535} 7536 7537void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7538 IdentifierInfo* AliasName, 7539 SourceLocation PragmaLoc, 7540 SourceLocation NameLoc, 7541 SourceLocation AliasNameLoc) { 7542 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7543 LookupOrdinaryName); 7544 WeakInfo W = WeakInfo(Name, NameLoc); 7545 7546 if (PrevDecl) { 7547 if (!PrevDecl->hasAttr<AliasAttr>()) 7548 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7549 DeclApplyPragmaWeak(TUScope, ND, W); 7550 } else { 7551 (void)WeakUndeclaredIdentifiers.insert( 7552 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7553 } 7554} 7555