SemaDecl.cpp revision 9ae2f076ca5ab1feb3ba95629099ec2319833701
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/Sema.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Sema/DeclSpec.h" 25#include "clang/Sema/ParsedTemplate.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(Decl *D) { 42 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 43 return DN->getQualifiedNameAsString(); 44 return ""; 45} 46 47Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 48 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 49} 50 51/// \brief If the identifier refers to a type name within this scope, 52/// return the declaration of that type. 53/// 54/// This routine performs ordinary name lookup of the identifier II 55/// within the given scope, with optional C++ scope specifier SS, to 56/// determine whether the name refers to a type. If so, returns an 57/// opaque pointer (actually a QualType) corresponding to that 58/// type. Otherwise, returns NULL. 59/// 60/// If name lookup results in an ambiguity, this routine will complain 61/// and then return NULL. 62Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, CXXScopeSpec *SS, 64 bool isClassName, 65 TypeTy *ObjectTypePtr) { 66 // Determine where we will perform name lookup. 67 DeclContext *LookupCtx = 0; 68 if (ObjectTypePtr) { 69 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 70 if (ObjectType->isRecordType()) 71 LookupCtx = computeDeclContext(ObjectType); 72 } else if (SS && SS->isNotEmpty()) { 73 LookupCtx = computeDeclContext(*SS, false); 74 75 if (!LookupCtx) { 76 if (isDependentScopeSpecifier(*SS)) { 77 // C++ [temp.res]p3: 78 // A qualified-id that refers to a type and in which the 79 // nested-name-specifier depends on a template-parameter (14.6.2) 80 // shall be prefixed by the keyword typename to indicate that the 81 // qualified-id denotes a type, forming an 82 // elaborated-type-specifier (7.1.5.3). 83 // 84 // We therefore do not perform any name lookup if the result would 85 // refer to a member of an unknown specialization. 86 if (!isClassName) 87 return 0; 88 89 // We know from the grammar that this name refers to a type, 90 // so build a dependent node to describe the type. 91 return CheckTypenameType(ETK_None, 92 (NestedNameSpecifier *)SS->getScopeRep(), II, 93 SourceLocation(), SS->getRange(), NameLoc 94 ).getAsOpaquePtr(); 95 } 96 97 return 0; 98 } 99 100 if (!LookupCtx->isDependentContext() && 101 RequireCompleteDeclContext(*SS, LookupCtx)) 102 return 0; 103 } 104 105 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 106 // lookup for class-names. 107 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 108 LookupOrdinaryName; 109 LookupResult Result(*this, &II, NameLoc, Kind); 110 if (LookupCtx) { 111 // Perform "qualified" name lookup into the declaration context we 112 // computed, which is either the type of the base of a member access 113 // expression or the declaration context associated with a prior 114 // nested-name-specifier. 115 LookupQualifiedName(Result, LookupCtx); 116 117 if (ObjectTypePtr && Result.empty()) { 118 // C++ [basic.lookup.classref]p3: 119 // If the unqualified-id is ~type-name, the type-name is looked up 120 // in the context of the entire postfix-expression. If the type T of 121 // the object expression is of a class type C, the type-name is also 122 // looked up in the scope of class C. At least one of the lookups shall 123 // find a name that refers to (possibly cv-qualified) T. 124 LookupName(Result, S); 125 } 126 } else { 127 // Perform unqualified name lookup. 128 LookupName(Result, S); 129 } 130 131 NamedDecl *IIDecl = 0; 132 switch (Result.getResultKind()) { 133 case LookupResult::NotFound: 134 case LookupResult::NotFoundInCurrentInstantiation: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 Result.suppressDiagnostics(); 138 return 0; 139 140 case LookupResult::Ambiguous: 141 // Recover from type-hiding ambiguities by hiding the type. We'll 142 // do the lookup again when looking for an object, and we can 143 // diagnose the error then. If we don't do this, then the error 144 // about hiding the type will be immediately followed by an error 145 // that only makes sense if the identifier was treated like a type. 146 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 147 Result.suppressDiagnostics(); 148 return 0; 149 } 150 151 // Look to see if we have a type anywhere in the list of results. 152 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 153 Res != ResEnd; ++Res) { 154 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 155 if (!IIDecl || 156 (*Res)->getLocation().getRawEncoding() < 157 IIDecl->getLocation().getRawEncoding()) 158 IIDecl = *Res; 159 } 160 } 161 162 if (!IIDecl) { 163 // None of the entities we found is a type, so there is no way 164 // to even assume that the result is a type. In this case, don't 165 // complain about the ambiguity. The parser will either try to 166 // perform this lookup again (e.g., as an object name), which 167 // will produce the ambiguity, or will complain that it expected 168 // a type name. 169 Result.suppressDiagnostics(); 170 return 0; 171 } 172 173 // We found a type within the ambiguous lookup; diagnose the 174 // ambiguity and then return that type. This might be the right 175 // answer, or it might not be, but it suppresses any attempt to 176 // perform the name lookup again. 177 break; 178 179 case LookupResult::Found: 180 IIDecl = Result.getFoundDecl(); 181 break; 182 } 183 184 assert(IIDecl && "Didn't find decl"); 185 186 QualType T; 187 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 188 DiagnoseUseOfDecl(IIDecl, NameLoc); 189 190 if (T.isNull()) 191 T = Context.getTypeDeclType(TD); 192 193 if (SS) 194 T = getElaboratedType(ETK_None, *SS, T); 195 196 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 197 T = Context.getObjCInterfaceType(IDecl); 198 } else { 199 // If it's not plausibly a type, suppress diagnostics. 200 Result.suppressDiagnostics(); 201 return 0; 202 } 203 204 return T.getAsOpaquePtr(); 205} 206 207/// isTagName() - This method is called *for error recovery purposes only* 208/// to determine if the specified name is a valid tag name ("struct foo"). If 209/// so, this returns the TST for the tag corresponding to it (TST_enum, 210/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 211/// where the user forgot to specify the tag. 212DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 213 // Do a tag name lookup in this scope. 214 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 215 LookupName(R, S, false); 216 R.suppressDiagnostics(); 217 if (R.getResultKind() == LookupResult::Found) 218 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 219 switch (TD->getTagKind()) { 220 default: return DeclSpec::TST_unspecified; 221 case TTK_Struct: return DeclSpec::TST_struct; 222 case TTK_Union: return DeclSpec::TST_union; 223 case TTK_Class: return DeclSpec::TST_class; 224 case TTK_Enum: return DeclSpec::TST_enum; 225 } 226 } 227 228 return DeclSpec::TST_unspecified; 229} 230 231bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 232 SourceLocation IILoc, 233 Scope *S, 234 CXXScopeSpec *SS, 235 TypeTy *&SuggestedType) { 236 // We don't have anything to suggest (yet). 237 SuggestedType = 0; 238 239 // There may have been a typo in the name of the type. Look up typo 240 // results, in case we have something that we can suggest. 241 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 242 NotForRedeclaration); 243 244 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 245 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 246 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 247 !Result->isInvalidDecl()) { 248 // We found a similarly-named type or interface; suggest that. 249 if (!SS || !SS->isSet()) 250 Diag(IILoc, diag::err_unknown_typename_suggest) 251 << &II << Lookup.getLookupName() 252 << FixItHint::CreateReplacement(SourceRange(IILoc), 253 Result->getNameAsString()); 254 else if (DeclContext *DC = computeDeclContext(*SS, false)) 255 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 256 << &II << DC << Lookup.getLookupName() << SS->getRange() 257 << FixItHint::CreateReplacement(SourceRange(IILoc), 258 Result->getNameAsString()); 259 else 260 llvm_unreachable("could not have corrected a typo here"); 261 262 Diag(Result->getLocation(), diag::note_previous_decl) 263 << Result->getDeclName(); 264 265 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 266 return true; 267 } 268 } else if (Lookup.empty()) { 269 // We corrected to a keyword. 270 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 271 Diag(IILoc, diag::err_unknown_typename_suggest) 272 << &II << Corrected; 273 return true; 274 } 275 } 276 277 if (getLangOptions().CPlusPlus) { 278 // See if II is a class template that the user forgot to pass arguments to. 279 UnqualifiedId Name; 280 Name.setIdentifier(&II, IILoc); 281 CXXScopeSpec EmptySS; 282 TemplateTy TemplateResult; 283 bool MemberOfUnknownSpecialization; 284 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 285 Name, 0, true, TemplateResult, 286 MemberOfUnknownSpecialization) == TNK_Type_template) { 287 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 288 Diag(IILoc, diag::err_template_missing_args) << TplName; 289 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 290 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 291 << TplDecl->getTemplateParameters()->getSourceRange(); 292 } 293 return true; 294 } 295 } 296 297 // FIXME: Should we move the logic that tries to recover from a missing tag 298 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 299 300 if (!SS || (!SS->isSet() && !SS->isInvalid())) 301 Diag(IILoc, diag::err_unknown_typename) << &II; 302 else if (DeclContext *DC = computeDeclContext(*SS, false)) 303 Diag(IILoc, diag::err_typename_nested_not_found) 304 << &II << DC << SS->getRange(); 305 else if (isDependentScopeSpecifier(*SS)) { 306 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 307 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 308 << SourceRange(SS->getRange().getBegin(), IILoc) 309 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 310 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 311 } else { 312 assert(SS && SS->isInvalid() && 313 "Invalid scope specifier has already been diagnosed"); 314 } 315 316 return true; 317} 318 319// Determines the context to return to after temporarily entering a 320// context. This depends in an unnecessarily complicated way on the 321// exact ordering of callbacks from the parser. 322DeclContext *Sema::getContainingDC(DeclContext *DC) { 323 324 // Functions defined inline within classes aren't parsed until we've 325 // finished parsing the top-level class, so the top-level class is 326 // the context we'll need to return to. 327 if (isa<FunctionDecl>(DC)) { 328 DC = DC->getLexicalParent(); 329 330 // A function not defined within a class will always return to its 331 // lexical context. 332 if (!isa<CXXRecordDecl>(DC)) 333 return DC; 334 335 // A C++ inline method/friend is parsed *after* the topmost class 336 // it was declared in is fully parsed ("complete"); the topmost 337 // class is the context we need to return to. 338 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 339 DC = RD; 340 341 // Return the declaration context of the topmost class the inline method is 342 // declared in. 343 return DC; 344 } 345 346 // ObjCMethodDecls are parsed (for some reason) outside the context 347 // of the class. 348 if (isa<ObjCMethodDecl>(DC)) 349 return DC->getLexicalParent()->getLexicalParent(); 350 351 return DC->getLexicalParent(); 352} 353 354void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 355 assert(getContainingDC(DC) == CurContext && 356 "The next DeclContext should be lexically contained in the current one."); 357 CurContext = DC; 358 S->setEntity(DC); 359} 360 361void Sema::PopDeclContext() { 362 assert(CurContext && "DeclContext imbalance!"); 363 364 CurContext = getContainingDC(CurContext); 365 assert(CurContext && "Popped translation unit!"); 366} 367 368/// EnterDeclaratorContext - Used when we must lookup names in the context 369/// of a declarator's nested name specifier. 370/// 371void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 372 // C++0x [basic.lookup.unqual]p13: 373 // A name used in the definition of a static data member of class 374 // X (after the qualified-id of the static member) is looked up as 375 // if the name was used in a member function of X. 376 // C++0x [basic.lookup.unqual]p14: 377 // If a variable member of a namespace is defined outside of the 378 // scope of its namespace then any name used in the definition of 379 // the variable member (after the declarator-id) is looked up as 380 // if the definition of the variable member occurred in its 381 // namespace. 382 // Both of these imply that we should push a scope whose context 383 // is the semantic context of the declaration. We can't use 384 // PushDeclContext here because that context is not necessarily 385 // lexically contained in the current context. Fortunately, 386 // the containing scope should have the appropriate information. 387 388 assert(!S->getEntity() && "scope already has entity"); 389 390#ifndef NDEBUG 391 Scope *Ancestor = S->getParent(); 392 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 393 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 394#endif 395 396 CurContext = DC; 397 S->setEntity(DC); 398} 399 400void Sema::ExitDeclaratorContext(Scope *S) { 401 assert(S->getEntity() == CurContext && "Context imbalance!"); 402 403 // Switch back to the lexical context. The safety of this is 404 // enforced by an assert in EnterDeclaratorContext. 405 Scope *Ancestor = S->getParent(); 406 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 407 CurContext = (DeclContext*) Ancestor->getEntity(); 408 409 // We don't need to do anything with the scope, which is going to 410 // disappear. 411} 412 413/// \brief Determine whether we allow overloading of the function 414/// PrevDecl with another declaration. 415/// 416/// This routine determines whether overloading is possible, not 417/// whether some new function is actually an overload. It will return 418/// true in C++ (where we can always provide overloads) or, as an 419/// extension, in C when the previous function is already an 420/// overloaded function declaration or has the "overloadable" 421/// attribute. 422static bool AllowOverloadingOfFunction(LookupResult &Previous, 423 ASTContext &Context) { 424 if (Context.getLangOptions().CPlusPlus) 425 return true; 426 427 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 428 return true; 429 430 return (Previous.getResultKind() == LookupResult::Found 431 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 432} 433 434/// Add this decl to the scope shadowed decl chains. 435void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 436 // Move up the scope chain until we find the nearest enclosing 437 // non-transparent context. The declaration will be introduced into this 438 // scope. 439 while (S->getEntity() && 440 ((DeclContext *)S->getEntity())->isTransparentContext()) 441 S = S->getParent(); 442 443 // Add scoped declarations into their context, so that they can be 444 // found later. Declarations without a context won't be inserted 445 // into any context. 446 if (AddToContext) 447 CurContext->addDecl(D); 448 449 // Out-of-line definitions shouldn't be pushed into scope in C++. 450 // Out-of-line variable and function definitions shouldn't even in C. 451 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 452 D->isOutOfLine()) 453 return; 454 455 // Template instantiations should also not be pushed into scope. 456 if (isa<FunctionDecl>(D) && 457 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 458 return; 459 460 // If this replaces anything in the current scope, 461 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 462 IEnd = IdResolver.end(); 463 for (; I != IEnd; ++I) { 464 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 465 S->RemoveDecl(*I); 466 IdResolver.RemoveDecl(*I); 467 468 // Should only need to replace one decl. 469 break; 470 } 471 } 472 473 S->AddDecl(D); 474 IdResolver.AddDecl(D); 475} 476 477bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 478 return IdResolver.isDeclInScope(D, Ctx, Context, S); 479} 480 481static bool isOutOfScopePreviousDeclaration(NamedDecl *, 482 DeclContext*, 483 ASTContext&); 484 485/// Filters out lookup results that don't fall within the given scope 486/// as determined by isDeclInScope. 487static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 488 DeclContext *Ctx, Scope *S, 489 bool ConsiderLinkage) { 490 LookupResult::Filter F = R.makeFilter(); 491 while (F.hasNext()) { 492 NamedDecl *D = F.next(); 493 494 if (SemaRef.isDeclInScope(D, Ctx, S)) 495 continue; 496 497 if (ConsiderLinkage && 498 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 499 continue; 500 501 F.erase(); 502 } 503 504 F.done(); 505} 506 507static bool isUsingDecl(NamedDecl *D) { 508 return isa<UsingShadowDecl>(D) || 509 isa<UnresolvedUsingTypenameDecl>(D) || 510 isa<UnresolvedUsingValueDecl>(D); 511} 512 513/// Removes using shadow declarations from the lookup results. 514static void RemoveUsingDecls(LookupResult &R) { 515 LookupResult::Filter F = R.makeFilter(); 516 while (F.hasNext()) 517 if (isUsingDecl(F.next())) 518 F.erase(); 519 520 F.done(); 521} 522 523/// \brief Check for this common pattern: 524/// @code 525/// class S { 526/// S(const S&); // DO NOT IMPLEMENT 527/// void operator=(const S&); // DO NOT IMPLEMENT 528/// }; 529/// @endcode 530static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 531 // FIXME: Should check for private access too but access is set after we get 532 // the decl here. 533 if (D->isThisDeclarationADefinition()) 534 return false; 535 536 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 537 return CD->isCopyConstructor(); 538 return D->isCopyAssignment(); 539} 540 541bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 542 assert(D); 543 544 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 545 return false; 546 547 // Ignore class templates. 548 if (D->getDeclContext()->isDependentContext()) 549 return false; 550 551 // We warn for unused decls internal to the translation unit. 552 if (D->getLinkage() == ExternalLinkage) 553 return false; 554 555 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 556 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 557 return false; 558 559 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 560 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 561 return false; 562 } else { 563 // 'static inline' functions are used in headers; don't warn. 564 if (FD->getStorageClass() == FunctionDecl::Static && 565 FD->isInlineSpecified()) 566 return false; 567 } 568 569 if (FD->isThisDeclarationADefinition()) 570 return !Context.DeclMustBeEmitted(FD); 571 return true; 572 } 573 574 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 575 if (VD->isStaticDataMember() && 576 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 577 return false; 578 579 if ( VD->isFileVarDecl() && 580 !VD->getType().isConstant(Context)) 581 return !Context.DeclMustBeEmitted(VD); 582 } 583 584 return false; 585 } 586 587 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 588 if (!D) 589 return; 590 591 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 592 const FunctionDecl *First = FD->getFirstDeclaration(); 593 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 594 return; // First should already be in the vector. 595 } 596 597 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 598 const VarDecl *First = VD->getFirstDeclaration(); 599 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 600 return; // First should already be in the vector. 601 } 602 603 if (ShouldWarnIfUnusedFileScopedDecl(D)) 604 UnusedFileScopedDecls.push_back(D); 605 } 606 607static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 608 if (D->isInvalidDecl()) 609 return false; 610 611 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 612 return false; 613 614 // White-list anything that isn't a local variable. 615 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 616 !D->getDeclContext()->isFunctionOrMethod()) 617 return false; 618 619 // Types of valid local variables should be complete, so this should succeed. 620 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 621 622 // White-list anything with an __attribute__((unused)) type. 623 QualType Ty = VD->getType(); 624 625 // Only look at the outermost level of typedef. 626 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 627 if (TT->getDecl()->hasAttr<UnusedAttr>()) 628 return false; 629 } 630 631 // If we failed to complete the type for some reason, or if the type is 632 // dependent, don't diagnose the variable. 633 if (Ty->isIncompleteType() || Ty->isDependentType()) 634 return false; 635 636 if (const TagType *TT = Ty->getAs<TagType>()) { 637 const TagDecl *Tag = TT->getDecl(); 638 if (Tag->hasAttr<UnusedAttr>()) 639 return false; 640 641 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 642 // FIXME: Checking for the presence of a user-declared constructor 643 // isn't completely accurate; we'd prefer to check that the initializer 644 // has no side effects. 645 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 646 return false; 647 } 648 } 649 650 // TODO: __attribute__((unused)) templates? 651 } 652 653 return true; 654} 655 656void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 657 if (!ShouldDiagnoseUnusedDecl(D)) 658 return; 659 660 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 661 Diag(D->getLocation(), diag::warn_unused_exception_param) 662 << D->getDeclName(); 663 else 664 Diag(D->getLocation(), diag::warn_unused_variable) 665 << D->getDeclName(); 666} 667 668void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 669 if (S->decl_empty()) return; 670 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 671 "Scope shouldn't contain decls!"); 672 673 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 674 I != E; ++I) { 675 Decl *TmpD = (*I); 676 assert(TmpD && "This decl didn't get pushed??"); 677 678 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 679 NamedDecl *D = cast<NamedDecl>(TmpD); 680 681 if (!D->getDeclName()) continue; 682 683 // Diagnose unused variables in this scope. 684 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 685 DiagnoseUnusedDecl(D); 686 687 // Remove this name from our lexical scope. 688 IdResolver.RemoveDecl(D); 689 } 690} 691 692/// \brief Look for an Objective-C class in the translation unit. 693/// 694/// \param Id The name of the Objective-C class we're looking for. If 695/// typo-correction fixes this name, the Id will be updated 696/// to the fixed name. 697/// 698/// \param IdLoc The location of the name in the translation unit. 699/// 700/// \param TypoCorrection If true, this routine will attempt typo correction 701/// if there is no class with the given name. 702/// 703/// \returns The declaration of the named Objective-C class, or NULL if the 704/// class could not be found. 705ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 706 SourceLocation IdLoc, 707 bool TypoCorrection) { 708 // The third "scope" argument is 0 since we aren't enabling lazy built-in 709 // creation from this context. 710 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 711 712 if (!IDecl && TypoCorrection) { 713 // Perform typo correction at the given location, but only if we 714 // find an Objective-C class name. 715 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 716 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 717 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 718 Diag(IdLoc, diag::err_undef_interface_suggest) 719 << Id << IDecl->getDeclName() 720 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 721 Diag(IDecl->getLocation(), diag::note_previous_decl) 722 << IDecl->getDeclName(); 723 724 Id = IDecl->getIdentifier(); 725 } 726 } 727 728 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 729} 730 731/// getNonFieldDeclScope - Retrieves the innermost scope, starting 732/// from S, where a non-field would be declared. This routine copes 733/// with the difference between C and C++ scoping rules in structs and 734/// unions. For example, the following code is well-formed in C but 735/// ill-formed in C++: 736/// @code 737/// struct S6 { 738/// enum { BAR } e; 739/// }; 740/// 741/// void test_S6() { 742/// struct S6 a; 743/// a.e = BAR; 744/// } 745/// @endcode 746/// For the declaration of BAR, this routine will return a different 747/// scope. The scope S will be the scope of the unnamed enumeration 748/// within S6. In C++, this routine will return the scope associated 749/// with S6, because the enumeration's scope is a transparent 750/// context but structures can contain non-field names. In C, this 751/// routine will return the translation unit scope, since the 752/// enumeration's scope is a transparent context and structures cannot 753/// contain non-field names. 754Scope *Sema::getNonFieldDeclScope(Scope *S) { 755 while (((S->getFlags() & Scope::DeclScope) == 0) || 756 (S->getEntity() && 757 ((DeclContext *)S->getEntity())->isTransparentContext()) || 758 (S->isClassScope() && !getLangOptions().CPlusPlus)) 759 S = S->getParent(); 760 return S; 761} 762 763void Sema::InitBuiltinVaListType() { 764 if (!Context.getBuiltinVaListType().isNull()) 765 return; 766 767 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 768 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 769 LookupOrdinaryName, ForRedeclaration); 770 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 771 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 772} 773 774/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 775/// file scope. lazily create a decl for it. ForRedeclaration is true 776/// if we're creating this built-in in anticipation of redeclaring the 777/// built-in. 778NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 779 Scope *S, bool ForRedeclaration, 780 SourceLocation Loc) { 781 Builtin::ID BID = (Builtin::ID)bid; 782 783 if (Context.BuiltinInfo.hasVAListUse(BID)) 784 InitBuiltinVaListType(); 785 786 ASTContext::GetBuiltinTypeError Error; 787 QualType R = Context.GetBuiltinType(BID, Error); 788 switch (Error) { 789 case ASTContext::GE_None: 790 // Okay 791 break; 792 793 case ASTContext::GE_Missing_stdio: 794 if (ForRedeclaration) 795 Diag(Loc, diag::err_implicit_decl_requires_stdio) 796 << Context.BuiltinInfo.GetName(BID); 797 return 0; 798 799 case ASTContext::GE_Missing_setjmp: 800 if (ForRedeclaration) 801 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 802 << Context.BuiltinInfo.GetName(BID); 803 return 0; 804 } 805 806 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 807 Diag(Loc, diag::ext_implicit_lib_function_decl) 808 << Context.BuiltinInfo.GetName(BID) 809 << R; 810 if (Context.BuiltinInfo.getHeaderName(BID) && 811 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 812 != Diagnostic::Ignored) 813 Diag(Loc, diag::note_please_include_header) 814 << Context.BuiltinInfo.getHeaderName(BID) 815 << Context.BuiltinInfo.GetName(BID); 816 } 817 818 FunctionDecl *New = FunctionDecl::Create(Context, 819 Context.getTranslationUnitDecl(), 820 Loc, II, R, /*TInfo=*/0, 821 FunctionDecl::Extern, 822 FunctionDecl::None, false, 823 /*hasPrototype=*/true); 824 New->setImplicit(); 825 826 // Create Decl objects for each parameter, adding them to the 827 // FunctionDecl. 828 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 829 llvm::SmallVector<ParmVarDecl*, 16> Params; 830 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 831 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 832 FT->getArgType(i), /*TInfo=*/0, 833 VarDecl::None, VarDecl::None, 0)); 834 New->setParams(Params.data(), Params.size()); 835 } 836 837 AddKnownFunctionAttributes(New); 838 839 // TUScope is the translation-unit scope to insert this function into. 840 // FIXME: This is hideous. We need to teach PushOnScopeChains to 841 // relate Scopes to DeclContexts, and probably eliminate CurContext 842 // entirely, but we're not there yet. 843 DeclContext *SavedContext = CurContext; 844 CurContext = Context.getTranslationUnitDecl(); 845 PushOnScopeChains(New, TUScope); 846 CurContext = SavedContext; 847 return New; 848} 849 850/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 851/// same name and scope as a previous declaration 'Old'. Figure out 852/// how to resolve this situation, merging decls or emitting 853/// diagnostics as appropriate. If there was an error, set New to be invalid. 854/// 855void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 856 // If the new decl is known invalid already, don't bother doing any 857 // merging checks. 858 if (New->isInvalidDecl()) return; 859 860 // Allow multiple definitions for ObjC built-in typedefs. 861 // FIXME: Verify the underlying types are equivalent! 862 if (getLangOptions().ObjC1) { 863 const IdentifierInfo *TypeID = New->getIdentifier(); 864 switch (TypeID->getLength()) { 865 default: break; 866 case 2: 867 if (!TypeID->isStr("id")) 868 break; 869 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 870 // Install the built-in type for 'id', ignoring the current definition. 871 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 872 return; 873 case 5: 874 if (!TypeID->isStr("Class")) 875 break; 876 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 877 // Install the built-in type for 'Class', ignoring the current definition. 878 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 879 return; 880 case 3: 881 if (!TypeID->isStr("SEL")) 882 break; 883 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 884 // Install the built-in type for 'SEL', ignoring the current definition. 885 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 886 return; 887 case 8: 888 if (!TypeID->isStr("Protocol")) 889 break; 890 Context.setObjCProtoType(New->getUnderlyingType()); 891 return; 892 } 893 // Fall through - the typedef name was not a builtin type. 894 } 895 896 // Verify the old decl was also a type. 897 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 898 if (!Old) { 899 Diag(New->getLocation(), diag::err_redefinition_different_kind) 900 << New->getDeclName(); 901 902 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 903 if (OldD->getLocation().isValid()) 904 Diag(OldD->getLocation(), diag::note_previous_definition); 905 906 return New->setInvalidDecl(); 907 } 908 909 // If the old declaration is invalid, just give up here. 910 if (Old->isInvalidDecl()) 911 return New->setInvalidDecl(); 912 913 // Determine the "old" type we'll use for checking and diagnostics. 914 QualType OldType; 915 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 916 OldType = OldTypedef->getUnderlyingType(); 917 else 918 OldType = Context.getTypeDeclType(Old); 919 920 // If the typedef types are not identical, reject them in all languages and 921 // with any extensions enabled. 922 923 if (OldType != New->getUnderlyingType() && 924 Context.getCanonicalType(OldType) != 925 Context.getCanonicalType(New->getUnderlyingType())) { 926 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 927 << New->getUnderlyingType() << OldType; 928 if (Old->getLocation().isValid()) 929 Diag(Old->getLocation(), diag::note_previous_definition); 930 return New->setInvalidDecl(); 931 } 932 933 // The types match. Link up the redeclaration chain if the old 934 // declaration was a typedef. 935 // FIXME: this is a potential source of wierdness if the type 936 // spellings don't match exactly. 937 if (isa<TypedefDecl>(Old)) 938 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 939 940 if (getLangOptions().Microsoft) 941 return; 942 943 if (getLangOptions().CPlusPlus) { 944 // C++ [dcl.typedef]p2: 945 // In a given non-class scope, a typedef specifier can be used to 946 // redefine the name of any type declared in that scope to refer 947 // to the type to which it already refers. 948 if (!isa<CXXRecordDecl>(CurContext)) 949 return; 950 951 // C++0x [dcl.typedef]p4: 952 // In a given class scope, a typedef specifier can be used to redefine 953 // any class-name declared in that scope that is not also a typedef-name 954 // to refer to the type to which it already refers. 955 // 956 // This wording came in via DR424, which was a correction to the 957 // wording in DR56, which accidentally banned code like: 958 // 959 // struct S { 960 // typedef struct A { } A; 961 // }; 962 // 963 // in the C++03 standard. We implement the C++0x semantics, which 964 // allow the above but disallow 965 // 966 // struct S { 967 // typedef int I; 968 // typedef int I; 969 // }; 970 // 971 // since that was the intent of DR56. 972 if (!isa<TypedefDecl >(Old)) 973 return; 974 975 Diag(New->getLocation(), diag::err_redefinition) 976 << New->getDeclName(); 977 Diag(Old->getLocation(), diag::note_previous_definition); 978 return New->setInvalidDecl(); 979 } 980 981 // If we have a redefinition of a typedef in C, emit a warning. This warning 982 // is normally mapped to an error, but can be controlled with 983 // -Wtypedef-redefinition. If either the original or the redefinition is 984 // in a system header, don't emit this for compatibility with GCC. 985 if (getDiagnostics().getSuppressSystemWarnings() && 986 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 987 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 988 return; 989 990 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 991 << New->getDeclName(); 992 Diag(Old->getLocation(), diag::note_previous_definition); 993 return; 994} 995 996/// DeclhasAttr - returns true if decl Declaration already has the target 997/// attribute. 998static bool 999DeclHasAttr(const Decl *D, const Attr *A) { 1000 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1001 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1002 if ((*i)->getKind() == A->getKind()) { 1003 // FIXME: Don't hardcode this check 1004 if (OA && isa<OwnershipAttr>(*i)) 1005 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1006 return true; 1007 } 1008 1009 return false; 1010} 1011 1012/// MergeDeclAttributes - append attributes from the Old decl to the New one. 1013static void MergeDeclAttributes(Decl *New, Decl *Old, ASTContext &C) { 1014 if (!Old->hasAttrs()) 1015 return; 1016 // Ensure that any moving of objects within the allocated map is done before 1017 // we process them. 1018 if (!New->hasAttrs()) 1019 New->setAttrs(AttrVec()); 1020 for (Decl::attr_iterator i = Old->attr_begin(), e = Old->attr_end(); i != e; 1021 ++i) { 1022 // FIXME: Make this more general than just checking for Overloadable. 1023 if (!DeclHasAttr(New, *i) && (*i)->getKind() != attr::Overloadable) { 1024 Attr *NewAttr = (*i)->clone(C); 1025 NewAttr->setInherited(true); 1026 New->addAttr(NewAttr); 1027 } 1028 } 1029} 1030 1031namespace { 1032 1033/// Used in MergeFunctionDecl to keep track of function parameters in 1034/// C. 1035struct GNUCompatibleParamWarning { 1036 ParmVarDecl *OldParm; 1037 ParmVarDecl *NewParm; 1038 QualType PromotedType; 1039}; 1040 1041} 1042 1043/// getSpecialMember - get the special member enum for a method. 1044Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1045 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1046 if (Ctor->isCopyConstructor()) 1047 return Sema::CXXCopyConstructor; 1048 1049 return Sema::CXXConstructor; 1050 } 1051 1052 if (isa<CXXDestructorDecl>(MD)) 1053 return Sema::CXXDestructor; 1054 1055 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 1056 return Sema::CXXCopyAssignment; 1057} 1058 1059/// canRedefineFunction - checks if a function can be redefined. Currently, 1060/// only extern inline functions can be redefined, and even then only in 1061/// GNU89 mode. 1062static bool canRedefineFunction(const FunctionDecl *FD, 1063 const LangOptions& LangOpts) { 1064 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1065 FD->isInlineSpecified() && 1066 FD->getStorageClass() == FunctionDecl::Extern); 1067} 1068 1069/// MergeFunctionDecl - We just parsed a function 'New' from 1070/// declarator D which has the same name and scope as a previous 1071/// declaration 'Old'. Figure out how to resolve this situation, 1072/// merging decls or emitting diagnostics as appropriate. 1073/// 1074/// In C++, New and Old must be declarations that are not 1075/// overloaded. Use IsOverload to determine whether New and Old are 1076/// overloaded, and to select the Old declaration that New should be 1077/// merged with. 1078/// 1079/// Returns true if there was an error, false otherwise. 1080bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1081 // Verify the old decl was also a function. 1082 FunctionDecl *Old = 0; 1083 if (FunctionTemplateDecl *OldFunctionTemplate 1084 = dyn_cast<FunctionTemplateDecl>(OldD)) 1085 Old = OldFunctionTemplate->getTemplatedDecl(); 1086 else 1087 Old = dyn_cast<FunctionDecl>(OldD); 1088 if (!Old) { 1089 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1090 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1091 Diag(Shadow->getTargetDecl()->getLocation(), 1092 diag::note_using_decl_target); 1093 Diag(Shadow->getUsingDecl()->getLocation(), 1094 diag::note_using_decl) << 0; 1095 return true; 1096 } 1097 1098 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1099 << New->getDeclName(); 1100 Diag(OldD->getLocation(), diag::note_previous_definition); 1101 return true; 1102 } 1103 1104 // Determine whether the previous declaration was a definition, 1105 // implicit declaration, or a declaration. 1106 diag::kind PrevDiag; 1107 if (Old->isThisDeclarationADefinition()) 1108 PrevDiag = diag::note_previous_definition; 1109 else if (Old->isImplicit()) 1110 PrevDiag = diag::note_previous_implicit_declaration; 1111 else 1112 PrevDiag = diag::note_previous_declaration; 1113 1114 QualType OldQType = Context.getCanonicalType(Old->getType()); 1115 QualType NewQType = Context.getCanonicalType(New->getType()); 1116 1117 // Don't complain about this if we're in GNU89 mode and the old function 1118 // is an extern inline function. 1119 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1120 New->getStorageClass() == FunctionDecl::Static && 1121 Old->getStorageClass() != FunctionDecl::Static && 1122 !canRedefineFunction(Old, getLangOptions())) { 1123 Diag(New->getLocation(), diag::err_static_non_static) 1124 << New; 1125 Diag(Old->getLocation(), PrevDiag); 1126 return true; 1127 } 1128 1129 // If a function is first declared with a calling convention, but is 1130 // later declared or defined without one, the second decl assumes the 1131 // calling convention of the first. 1132 // 1133 // For the new decl, we have to look at the NON-canonical type to tell the 1134 // difference between a function that really doesn't have a calling 1135 // convention and one that is declared cdecl. That's because in 1136 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1137 // because it is the default calling convention. 1138 // 1139 // Note also that we DO NOT return at this point, because we still have 1140 // other tests to run. 1141 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1142 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1143 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1144 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1145 if (OldTypeInfo.getCC() != CC_Default && 1146 NewTypeInfo.getCC() == CC_Default) { 1147 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1148 New->setType(NewQType); 1149 NewQType = Context.getCanonicalType(NewQType); 1150 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1151 NewTypeInfo.getCC())) { 1152 // Calling conventions really aren't compatible, so complain. 1153 Diag(New->getLocation(), diag::err_cconv_change) 1154 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1155 << (OldTypeInfo.getCC() == CC_Default) 1156 << (OldTypeInfo.getCC() == CC_Default ? "" : 1157 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1158 Diag(Old->getLocation(), diag::note_previous_declaration); 1159 return true; 1160 } 1161 1162 // FIXME: diagnose the other way around? 1163 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1164 NewQType = Context.getNoReturnType(NewQType); 1165 New->setType(NewQType); 1166 assert(NewQType.isCanonical()); 1167 } 1168 1169 // Merge regparm attribute. 1170 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1171 if (NewType->getRegParmType()) { 1172 Diag(New->getLocation(), diag::err_regparm_mismatch) 1173 << NewType->getRegParmType() 1174 << OldType->getRegParmType(); 1175 Diag(Old->getLocation(), diag::note_previous_declaration); 1176 return true; 1177 } 1178 1179 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1180 New->setType(NewQType); 1181 assert(NewQType.isCanonical()); 1182 } 1183 1184 if (getLangOptions().CPlusPlus) { 1185 // (C++98 13.1p2): 1186 // Certain function declarations cannot be overloaded: 1187 // -- Function declarations that differ only in the return type 1188 // cannot be overloaded. 1189 QualType OldReturnType 1190 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1191 QualType NewReturnType 1192 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1193 QualType ResQT; 1194 if (OldReturnType != NewReturnType) { 1195 if (NewReturnType->isObjCObjectPointerType() 1196 && OldReturnType->isObjCObjectPointerType()) 1197 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1198 if (ResQT.isNull()) { 1199 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1200 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1201 return true; 1202 } 1203 else 1204 NewQType = ResQT; 1205 } 1206 1207 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1208 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1209 if (OldMethod && NewMethod) { 1210 // Preserve triviality. 1211 NewMethod->setTrivial(OldMethod->isTrivial()); 1212 1213 bool isFriend = NewMethod->getFriendObjectKind(); 1214 1215 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1216 // -- Member function declarations with the same name and the 1217 // same parameter types cannot be overloaded if any of them 1218 // is a static member function declaration. 1219 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1220 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1221 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1222 return true; 1223 } 1224 1225 // C++ [class.mem]p1: 1226 // [...] A member shall not be declared twice in the 1227 // member-specification, except that a nested class or member 1228 // class template can be declared and then later defined. 1229 unsigned NewDiag; 1230 if (isa<CXXConstructorDecl>(OldMethod)) 1231 NewDiag = diag::err_constructor_redeclared; 1232 else if (isa<CXXDestructorDecl>(NewMethod)) 1233 NewDiag = diag::err_destructor_redeclared; 1234 else if (isa<CXXConversionDecl>(NewMethod)) 1235 NewDiag = diag::err_conv_function_redeclared; 1236 else 1237 NewDiag = diag::err_member_redeclared; 1238 1239 Diag(New->getLocation(), NewDiag); 1240 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1241 1242 // Complain if this is an explicit declaration of a special 1243 // member that was initially declared implicitly. 1244 // 1245 // As an exception, it's okay to befriend such methods in order 1246 // to permit the implicit constructor/destructor/operator calls. 1247 } else if (OldMethod->isImplicit()) { 1248 if (isFriend) { 1249 NewMethod->setImplicit(); 1250 } else { 1251 Diag(NewMethod->getLocation(), 1252 diag::err_definition_of_implicitly_declared_member) 1253 << New << getSpecialMember(OldMethod); 1254 return true; 1255 } 1256 } 1257 } 1258 1259 // (C++98 8.3.5p3): 1260 // All declarations for a function shall agree exactly in both the 1261 // return type and the parameter-type-list. 1262 // attributes should be ignored when comparing. 1263 if (Context.getNoReturnType(OldQType, false) == 1264 Context.getNoReturnType(NewQType, false)) 1265 return MergeCompatibleFunctionDecls(New, Old); 1266 1267 // Fall through for conflicting redeclarations and redefinitions. 1268 } 1269 1270 // C: Function types need to be compatible, not identical. This handles 1271 // duplicate function decls like "void f(int); void f(enum X);" properly. 1272 if (!getLangOptions().CPlusPlus && 1273 Context.typesAreCompatible(OldQType, NewQType)) { 1274 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1275 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1276 const FunctionProtoType *OldProto = 0; 1277 if (isa<FunctionNoProtoType>(NewFuncType) && 1278 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1279 // The old declaration provided a function prototype, but the 1280 // new declaration does not. Merge in the prototype. 1281 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1282 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1283 OldProto->arg_type_end()); 1284 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1285 ParamTypes.data(), ParamTypes.size(), 1286 OldProto->isVariadic(), 1287 OldProto->getTypeQuals(), 1288 false, false, 0, 0, 1289 OldProto->getExtInfo()); 1290 New->setType(NewQType); 1291 New->setHasInheritedPrototype(); 1292 1293 // Synthesize a parameter for each argument type. 1294 llvm::SmallVector<ParmVarDecl*, 16> Params; 1295 for (FunctionProtoType::arg_type_iterator 1296 ParamType = OldProto->arg_type_begin(), 1297 ParamEnd = OldProto->arg_type_end(); 1298 ParamType != ParamEnd; ++ParamType) { 1299 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1300 SourceLocation(), 0, 1301 *ParamType, /*TInfo=*/0, 1302 VarDecl::None, VarDecl::None, 1303 0); 1304 Param->setImplicit(); 1305 Params.push_back(Param); 1306 } 1307 1308 New->setParams(Params.data(), Params.size()); 1309 } 1310 1311 return MergeCompatibleFunctionDecls(New, Old); 1312 } 1313 1314 // GNU C permits a K&R definition to follow a prototype declaration 1315 // if the declared types of the parameters in the K&R definition 1316 // match the types in the prototype declaration, even when the 1317 // promoted types of the parameters from the K&R definition differ 1318 // from the types in the prototype. GCC then keeps the types from 1319 // the prototype. 1320 // 1321 // If a variadic prototype is followed by a non-variadic K&R definition, 1322 // the K&R definition becomes variadic. This is sort of an edge case, but 1323 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1324 // C99 6.9.1p8. 1325 if (!getLangOptions().CPlusPlus && 1326 Old->hasPrototype() && !New->hasPrototype() && 1327 New->getType()->getAs<FunctionProtoType>() && 1328 Old->getNumParams() == New->getNumParams()) { 1329 llvm::SmallVector<QualType, 16> ArgTypes; 1330 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1331 const FunctionProtoType *OldProto 1332 = Old->getType()->getAs<FunctionProtoType>(); 1333 const FunctionProtoType *NewProto 1334 = New->getType()->getAs<FunctionProtoType>(); 1335 1336 // Determine whether this is the GNU C extension. 1337 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1338 NewProto->getResultType()); 1339 bool LooseCompatible = !MergedReturn.isNull(); 1340 for (unsigned Idx = 0, End = Old->getNumParams(); 1341 LooseCompatible && Idx != End; ++Idx) { 1342 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1343 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1344 if (Context.typesAreCompatible(OldParm->getType(), 1345 NewProto->getArgType(Idx))) { 1346 ArgTypes.push_back(NewParm->getType()); 1347 } else if (Context.typesAreCompatible(OldParm->getType(), 1348 NewParm->getType(), 1349 /*CompareUnqualified=*/true)) { 1350 GNUCompatibleParamWarning Warn 1351 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1352 Warnings.push_back(Warn); 1353 ArgTypes.push_back(NewParm->getType()); 1354 } else 1355 LooseCompatible = false; 1356 } 1357 1358 if (LooseCompatible) { 1359 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1360 Diag(Warnings[Warn].NewParm->getLocation(), 1361 diag::ext_param_promoted_not_compatible_with_prototype) 1362 << Warnings[Warn].PromotedType 1363 << Warnings[Warn].OldParm->getType(); 1364 if (Warnings[Warn].OldParm->getLocation().isValid()) 1365 Diag(Warnings[Warn].OldParm->getLocation(), 1366 diag::note_previous_declaration); 1367 } 1368 1369 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1370 ArgTypes.size(), 1371 OldProto->isVariadic(), 0, 1372 false, false, 0, 0, 1373 OldProto->getExtInfo())); 1374 return MergeCompatibleFunctionDecls(New, Old); 1375 } 1376 1377 // Fall through to diagnose conflicting types. 1378 } 1379 1380 // A function that has already been declared has been redeclared or defined 1381 // with a different type- show appropriate diagnostic 1382 if (unsigned BuiltinID = Old->getBuiltinID()) { 1383 // The user has declared a builtin function with an incompatible 1384 // signature. 1385 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1386 // The function the user is redeclaring is a library-defined 1387 // function like 'malloc' or 'printf'. Warn about the 1388 // redeclaration, then pretend that we don't know about this 1389 // library built-in. 1390 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1391 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1392 << Old << Old->getType(); 1393 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1394 Old->setInvalidDecl(); 1395 return false; 1396 } 1397 1398 PrevDiag = diag::note_previous_builtin_declaration; 1399 } 1400 1401 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1402 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1403 return true; 1404} 1405 1406/// \brief Completes the merge of two function declarations that are 1407/// known to be compatible. 1408/// 1409/// This routine handles the merging of attributes and other 1410/// properties of function declarations form the old declaration to 1411/// the new declaration, once we know that New is in fact a 1412/// redeclaration of Old. 1413/// 1414/// \returns false 1415bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1416 // Merge the attributes 1417 MergeDeclAttributes(New, Old, Context); 1418 1419 // Merge the storage class. 1420 if (Old->getStorageClass() != FunctionDecl::Extern && 1421 Old->getStorageClass() != FunctionDecl::None) 1422 New->setStorageClass(Old->getStorageClass()); 1423 1424 // Merge "pure" flag. 1425 if (Old->isPure()) 1426 New->setPure(); 1427 1428 // Merge the "deleted" flag. 1429 if (Old->isDeleted()) 1430 New->setDeleted(); 1431 1432 if (getLangOptions().CPlusPlus) 1433 return MergeCXXFunctionDecl(New, Old); 1434 1435 return false; 1436} 1437 1438/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1439/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1440/// situation, merging decls or emitting diagnostics as appropriate. 1441/// 1442/// Tentative definition rules (C99 6.9.2p2) are checked by 1443/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1444/// definitions here, since the initializer hasn't been attached. 1445/// 1446void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1447 // If the new decl is already invalid, don't do any other checking. 1448 if (New->isInvalidDecl()) 1449 return; 1450 1451 // Verify the old decl was also a variable. 1452 VarDecl *Old = 0; 1453 if (!Previous.isSingleResult() || 1454 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1455 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1456 << New->getDeclName(); 1457 Diag(Previous.getRepresentativeDecl()->getLocation(), 1458 diag::note_previous_definition); 1459 return New->setInvalidDecl(); 1460 } 1461 1462 MergeDeclAttributes(New, Old, Context); 1463 1464 // Merge the types 1465 QualType MergedT; 1466 if (getLangOptions().CPlusPlus) { 1467 if (Context.hasSameType(New->getType(), Old->getType())) 1468 MergedT = New->getType(); 1469 // C++ [basic.link]p10: 1470 // [...] the types specified by all declarations referring to a given 1471 // object or function shall be identical, except that declarations for an 1472 // array object can specify array types that differ by the presence or 1473 // absence of a major array bound (8.3.4). 1474 else if (Old->getType()->isIncompleteArrayType() && 1475 New->getType()->isArrayType()) { 1476 CanQual<ArrayType> OldArray 1477 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1478 CanQual<ArrayType> NewArray 1479 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1480 if (OldArray->getElementType() == NewArray->getElementType()) 1481 MergedT = New->getType(); 1482 } else if (Old->getType()->isArrayType() && 1483 New->getType()->isIncompleteArrayType()) { 1484 CanQual<ArrayType> OldArray 1485 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1486 CanQual<ArrayType> NewArray 1487 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1488 if (OldArray->getElementType() == NewArray->getElementType()) 1489 MergedT = Old->getType(); 1490 } else if (New->getType()->isObjCObjectPointerType() 1491 && Old->getType()->isObjCObjectPointerType()) { 1492 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1493 } 1494 } else { 1495 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1496 } 1497 if (MergedT.isNull()) { 1498 Diag(New->getLocation(), diag::err_redefinition_different_type) 1499 << New->getDeclName(); 1500 Diag(Old->getLocation(), diag::note_previous_definition); 1501 return New->setInvalidDecl(); 1502 } 1503 New->setType(MergedT); 1504 1505 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1506 if (New->getStorageClass() == VarDecl::Static && 1507 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1508 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1509 Diag(Old->getLocation(), diag::note_previous_definition); 1510 return New->setInvalidDecl(); 1511 } 1512 // C99 6.2.2p4: 1513 // For an identifier declared with the storage-class specifier 1514 // extern in a scope in which a prior declaration of that 1515 // identifier is visible,23) if the prior declaration specifies 1516 // internal or external linkage, the linkage of the identifier at 1517 // the later declaration is the same as the linkage specified at 1518 // the prior declaration. If no prior declaration is visible, or 1519 // if the prior declaration specifies no linkage, then the 1520 // identifier has external linkage. 1521 if (New->hasExternalStorage() && Old->hasLinkage()) 1522 /* Okay */; 1523 else if (New->getStorageClass() != VarDecl::Static && 1524 Old->getStorageClass() == VarDecl::Static) { 1525 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1526 Diag(Old->getLocation(), diag::note_previous_definition); 1527 return New->setInvalidDecl(); 1528 } 1529 1530 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1531 1532 // FIXME: The test for external storage here seems wrong? We still 1533 // need to check for mismatches. 1534 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1535 // Don't complain about out-of-line definitions of static members. 1536 !(Old->getLexicalDeclContext()->isRecord() && 1537 !New->getLexicalDeclContext()->isRecord())) { 1538 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1539 Diag(Old->getLocation(), diag::note_previous_definition); 1540 return New->setInvalidDecl(); 1541 } 1542 1543 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1544 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1545 Diag(Old->getLocation(), diag::note_previous_definition); 1546 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1547 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1548 Diag(Old->getLocation(), diag::note_previous_definition); 1549 } 1550 1551 // C++ doesn't have tentative definitions, so go right ahead and check here. 1552 const VarDecl *Def; 1553 if (getLangOptions().CPlusPlus && 1554 New->isThisDeclarationADefinition() == VarDecl::Definition && 1555 (Def = Old->getDefinition())) { 1556 Diag(New->getLocation(), diag::err_redefinition) 1557 << New->getDeclName(); 1558 Diag(Def->getLocation(), diag::note_previous_definition); 1559 New->setInvalidDecl(); 1560 return; 1561 } 1562 // c99 6.2.2 P4. 1563 // For an identifier declared with the storage-class specifier extern in a 1564 // scope in which a prior declaration of that identifier is visible, if 1565 // the prior declaration specifies internal or external linkage, the linkage 1566 // of the identifier at the later declaration is the same as the linkage 1567 // specified at the prior declaration. 1568 // FIXME. revisit this code. 1569 if (New->hasExternalStorage() && 1570 Old->getLinkage() == InternalLinkage && 1571 New->getDeclContext() == Old->getDeclContext()) 1572 New->setStorageClass(Old->getStorageClass()); 1573 1574 // Keep a chain of previous declarations. 1575 New->setPreviousDeclaration(Old); 1576 1577 // Inherit access appropriately. 1578 New->setAccess(Old->getAccess()); 1579} 1580 1581/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1582/// no declarator (e.g. "struct foo;") is parsed. 1583Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1584 DeclSpec &DS) { 1585 // FIXME: Error on auto/register at file scope 1586 // FIXME: Error on inline/virtual/explicit 1587 // FIXME: Warn on useless __thread 1588 // FIXME: Warn on useless const/volatile 1589 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1590 // FIXME: Warn on useless attributes 1591 Decl *TagD = 0; 1592 TagDecl *Tag = 0; 1593 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1594 DS.getTypeSpecType() == DeclSpec::TST_struct || 1595 DS.getTypeSpecType() == DeclSpec::TST_union || 1596 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1597 TagD = static_cast<Decl *>(DS.getTypeRep()); 1598 1599 if (!TagD) // We probably had an error 1600 return 0; 1601 1602 // Note that the above type specs guarantee that the 1603 // type rep is a Decl, whereas in many of the others 1604 // it's a Type. 1605 Tag = dyn_cast<TagDecl>(TagD); 1606 } 1607 1608 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1609 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1610 // or incomplete types shall not be restrict-qualified." 1611 if (TypeQuals & DeclSpec::TQ_restrict) 1612 Diag(DS.getRestrictSpecLoc(), 1613 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1614 << DS.getSourceRange(); 1615 } 1616 1617 if (DS.isFriendSpecified()) { 1618 // If we're dealing with a class template decl, assume that the 1619 // template routines are handling it. 1620 if (TagD && isa<ClassTemplateDecl>(TagD)) 1621 return 0; 1622 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1623 } 1624 1625 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1626 ProcessDeclAttributeList(S, Record, DS.getAttributes()); 1627 1628 if (!Record->getDeclName() && Record->isDefinition() && 1629 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1630 if (getLangOptions().CPlusPlus || 1631 Record->getDeclContext()->isRecord()) 1632 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1633 1634 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1635 << DS.getSourceRange(); 1636 } 1637 1638 // Microsoft allows unnamed struct/union fields. Don't complain 1639 // about them. 1640 // FIXME: Should we support Microsoft's extensions in this area? 1641 if (Record->getDeclName() && getLangOptions().Microsoft) 1642 return Tag; 1643 } 1644 1645 if (getLangOptions().CPlusPlus && 1646 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1647 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1648 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1649 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1650 Diag(Enum->getLocation(), diag::ext_no_declarators) 1651 << DS.getSourceRange(); 1652 1653 if (!DS.isMissingDeclaratorOk() && 1654 DS.getTypeSpecType() != DeclSpec::TST_error) { 1655 // Warn about typedefs of enums without names, since this is an 1656 // extension in both Microsoft and GNU. 1657 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1658 Tag && isa<EnumDecl>(Tag)) { 1659 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1660 << DS.getSourceRange(); 1661 return Tag; 1662 } 1663 1664 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1665 << DS.getSourceRange(); 1666 } 1667 1668 return TagD; 1669} 1670 1671/// We are trying to inject an anonymous member into the given scope; 1672/// check if there's an existing declaration that can't be overloaded. 1673/// 1674/// \return true if this is a forbidden redeclaration 1675static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1676 Scope *S, 1677 DeclContext *Owner, 1678 DeclarationName Name, 1679 SourceLocation NameLoc, 1680 unsigned diagnostic) { 1681 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1682 Sema::ForRedeclaration); 1683 if (!SemaRef.LookupName(R, S)) return false; 1684 1685 if (R.getAsSingle<TagDecl>()) 1686 return false; 1687 1688 // Pick a representative declaration. 1689 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1690 if (PrevDecl && Owner->isRecord()) { 1691 RecordDecl *Record = cast<RecordDecl>(Owner); 1692 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1693 return false; 1694 } 1695 1696 SemaRef.Diag(NameLoc, diagnostic) << Name; 1697 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1698 1699 return true; 1700} 1701 1702/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1703/// anonymous struct or union AnonRecord into the owning context Owner 1704/// and scope S. This routine will be invoked just after we realize 1705/// that an unnamed union or struct is actually an anonymous union or 1706/// struct, e.g., 1707/// 1708/// @code 1709/// union { 1710/// int i; 1711/// float f; 1712/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1713/// // f into the surrounding scope.x 1714/// @endcode 1715/// 1716/// This routine is recursive, injecting the names of nested anonymous 1717/// structs/unions into the owning context and scope as well. 1718static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1719 DeclContext *Owner, 1720 RecordDecl *AnonRecord, 1721 AccessSpecifier AS) { 1722 unsigned diagKind 1723 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1724 : diag::err_anonymous_struct_member_redecl; 1725 1726 bool Invalid = false; 1727 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1728 FEnd = AnonRecord->field_end(); 1729 F != FEnd; ++F) { 1730 if ((*F)->getDeclName()) { 1731 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1732 (*F)->getLocation(), diagKind)) { 1733 // C++ [class.union]p2: 1734 // The names of the members of an anonymous union shall be 1735 // distinct from the names of any other entity in the 1736 // scope in which the anonymous union is declared. 1737 Invalid = true; 1738 } else { 1739 // C++ [class.union]p2: 1740 // For the purpose of name lookup, after the anonymous union 1741 // definition, the members of the anonymous union are 1742 // considered to have been defined in the scope in which the 1743 // anonymous union is declared. 1744 Owner->makeDeclVisibleInContext(*F); 1745 S->AddDecl(*F); 1746 SemaRef.IdResolver.AddDecl(*F); 1747 1748 // That includes picking up the appropriate access specifier. 1749 if (AS != AS_none) (*F)->setAccess(AS); 1750 } 1751 } else if (const RecordType *InnerRecordType 1752 = (*F)->getType()->getAs<RecordType>()) { 1753 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1754 if (InnerRecord->isAnonymousStructOrUnion()) 1755 Invalid = Invalid || 1756 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1757 InnerRecord, AS); 1758 } 1759 } 1760 1761 return Invalid; 1762} 1763 1764/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1765/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1766/// illegal input values are mapped to VarDecl::None. 1767static VarDecl::StorageClass 1768StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1769 switch (StorageClassSpec) { 1770 case DeclSpec::SCS_unspecified: return VarDecl::None; 1771 case DeclSpec::SCS_extern: return VarDecl::Extern; 1772 case DeclSpec::SCS_static: return VarDecl::Static; 1773 case DeclSpec::SCS_auto: return VarDecl::Auto; 1774 case DeclSpec::SCS_register: return VarDecl::Register; 1775 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1776 // Illegal SCSs map to None: error reporting is up to the caller. 1777 case DeclSpec::SCS_mutable: // Fall through. 1778 case DeclSpec::SCS_typedef: return VarDecl::None; 1779 } 1780 llvm_unreachable("unknown storage class specifier"); 1781} 1782 1783/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1784/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1785/// illegal input values are mapped to FunctionDecl::None. 1786static FunctionDecl::StorageClass 1787StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1788 switch (StorageClassSpec) { 1789 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1790 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1791 case DeclSpec::SCS_static: return FunctionDecl::Static; 1792 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1793 // Illegal SCSs map to None: error reporting is up to the caller. 1794 case DeclSpec::SCS_auto: // Fall through. 1795 case DeclSpec::SCS_mutable: // Fall through. 1796 case DeclSpec::SCS_register: // Fall through. 1797 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1798 } 1799 llvm_unreachable("unknown storage class specifier"); 1800} 1801 1802/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1803/// anonymous structure or union. Anonymous unions are a C++ feature 1804/// (C++ [class.union]) and a GNU C extension; anonymous structures 1805/// are a GNU C and GNU C++ extension. 1806Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1807 AccessSpecifier AS, 1808 RecordDecl *Record) { 1809 DeclContext *Owner = Record->getDeclContext(); 1810 1811 // Diagnose whether this anonymous struct/union is an extension. 1812 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1813 Diag(Record->getLocation(), diag::ext_anonymous_union); 1814 else if (!Record->isUnion()) 1815 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1816 1817 // C and C++ require different kinds of checks for anonymous 1818 // structs/unions. 1819 bool Invalid = false; 1820 if (getLangOptions().CPlusPlus) { 1821 const char* PrevSpec = 0; 1822 unsigned DiagID; 1823 // C++ [class.union]p3: 1824 // Anonymous unions declared in a named namespace or in the 1825 // global namespace shall be declared static. 1826 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1827 (isa<TranslationUnitDecl>(Owner) || 1828 (isa<NamespaceDecl>(Owner) && 1829 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1830 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1831 Invalid = true; 1832 1833 // Recover by adding 'static'. 1834 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1835 PrevSpec, DiagID); 1836 } 1837 // C++ [class.union]p3: 1838 // A storage class is not allowed in a declaration of an 1839 // anonymous union in a class scope. 1840 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1841 isa<RecordDecl>(Owner)) { 1842 Diag(DS.getStorageClassSpecLoc(), 1843 diag::err_anonymous_union_with_storage_spec); 1844 Invalid = true; 1845 1846 // Recover by removing the storage specifier. 1847 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1848 PrevSpec, DiagID); 1849 } 1850 1851 // C++ [class.union]p2: 1852 // The member-specification of an anonymous union shall only 1853 // define non-static data members. [Note: nested types and 1854 // functions cannot be declared within an anonymous union. ] 1855 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1856 MemEnd = Record->decls_end(); 1857 Mem != MemEnd; ++Mem) { 1858 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1859 // C++ [class.union]p3: 1860 // An anonymous union shall not have private or protected 1861 // members (clause 11). 1862 assert(FD->getAccess() != AS_none); 1863 if (FD->getAccess() != AS_public) { 1864 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1865 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1866 Invalid = true; 1867 } 1868 1869 if (CheckNontrivialField(FD)) 1870 Invalid = true; 1871 } else if ((*Mem)->isImplicit()) { 1872 // Any implicit members are fine. 1873 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1874 // This is a type that showed up in an 1875 // elaborated-type-specifier inside the anonymous struct or 1876 // union, but which actually declares a type outside of the 1877 // anonymous struct or union. It's okay. 1878 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1879 if (!MemRecord->isAnonymousStructOrUnion() && 1880 MemRecord->getDeclName()) { 1881 // This is a nested type declaration. 1882 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1883 << (int)Record->isUnion(); 1884 Invalid = true; 1885 } 1886 } else if (isa<AccessSpecDecl>(*Mem)) { 1887 // Any access specifier is fine. 1888 } else { 1889 // We have something that isn't a non-static data 1890 // member. Complain about it. 1891 unsigned DK = diag::err_anonymous_record_bad_member; 1892 if (isa<TypeDecl>(*Mem)) 1893 DK = diag::err_anonymous_record_with_type; 1894 else if (isa<FunctionDecl>(*Mem)) 1895 DK = diag::err_anonymous_record_with_function; 1896 else if (isa<VarDecl>(*Mem)) 1897 DK = diag::err_anonymous_record_with_static; 1898 Diag((*Mem)->getLocation(), DK) 1899 << (int)Record->isUnion(); 1900 Invalid = true; 1901 } 1902 } 1903 } 1904 1905 if (!Record->isUnion() && !Owner->isRecord()) { 1906 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1907 << (int)getLangOptions().CPlusPlus; 1908 Invalid = true; 1909 } 1910 1911 // Mock up a declarator. 1912 Declarator Dc(DS, Declarator::TypeNameContext); 1913 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1914 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1915 1916 // Create a declaration for this anonymous struct/union. 1917 NamedDecl *Anon = 0; 1918 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1919 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1920 /*IdentifierInfo=*/0, 1921 Context.getTypeDeclType(Record), 1922 TInfo, 1923 /*BitWidth=*/0, /*Mutable=*/false); 1924 Anon->setAccess(AS); 1925 if (getLangOptions().CPlusPlus) { 1926 FieldCollector->Add(cast<FieldDecl>(Anon)); 1927 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1928 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1929 } 1930 } else { 1931 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1932 assert(SCSpec != DeclSpec::SCS_typedef && 1933 "Parser allowed 'typedef' as storage class VarDecl."); 1934 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1935 if (SCSpec == DeclSpec::SCS_mutable) { 1936 // mutable can only appear on non-static class members, so it's always 1937 // an error here 1938 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1939 Invalid = true; 1940 SC = VarDecl::None; 1941 } 1942 SCSpec = DS.getStorageClassSpecAsWritten(); 1943 VarDecl::StorageClass SCAsWritten 1944 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1945 1946 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1947 /*IdentifierInfo=*/0, 1948 Context.getTypeDeclType(Record), 1949 TInfo, SC, SCAsWritten); 1950 } 1951 Anon->setImplicit(); 1952 1953 // Add the anonymous struct/union object to the current 1954 // context. We'll be referencing this object when we refer to one of 1955 // its members. 1956 Owner->addDecl(Anon); 1957 1958 // Inject the members of the anonymous struct/union into the owning 1959 // context and into the identifier resolver chain for name lookup 1960 // purposes. 1961 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1962 Invalid = true; 1963 1964 // Mark this as an anonymous struct/union type. Note that we do not 1965 // do this until after we have already checked and injected the 1966 // members of this anonymous struct/union type, because otherwise 1967 // the members could be injected twice: once by DeclContext when it 1968 // builds its lookup table, and once by 1969 // InjectAnonymousStructOrUnionMembers. 1970 Record->setAnonymousStructOrUnion(true); 1971 1972 if (Invalid) 1973 Anon->setInvalidDecl(); 1974 1975 return Anon; 1976} 1977 1978 1979/// GetNameForDeclarator - Determine the full declaration name for the 1980/// given Declarator. 1981DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 1982 return GetNameFromUnqualifiedId(D.getName()); 1983} 1984 1985/// \brief Retrieves the declaration name from a parsed unqualified-id. 1986DeclarationNameInfo 1987Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1988 DeclarationNameInfo NameInfo; 1989 NameInfo.setLoc(Name.StartLocation); 1990 1991 switch (Name.getKind()) { 1992 1993 case UnqualifiedId::IK_Identifier: 1994 NameInfo.setName(Name.Identifier); 1995 NameInfo.setLoc(Name.StartLocation); 1996 return NameInfo; 1997 1998 case UnqualifiedId::IK_OperatorFunctionId: 1999 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2000 Name.OperatorFunctionId.Operator)); 2001 NameInfo.setLoc(Name.StartLocation); 2002 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2003 = Name.OperatorFunctionId.SymbolLocations[0]; 2004 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2005 = Name.EndLocation.getRawEncoding(); 2006 return NameInfo; 2007 2008 case UnqualifiedId::IK_LiteralOperatorId: 2009 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2010 Name.Identifier)); 2011 NameInfo.setLoc(Name.StartLocation); 2012 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2013 return NameInfo; 2014 2015 case UnqualifiedId::IK_ConversionFunctionId: { 2016 TypeSourceInfo *TInfo; 2017 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2018 if (Ty.isNull()) 2019 return DeclarationNameInfo(); 2020 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2021 Context.getCanonicalType(Ty))); 2022 NameInfo.setLoc(Name.StartLocation); 2023 NameInfo.setNamedTypeInfo(TInfo); 2024 return NameInfo; 2025 } 2026 2027 case UnqualifiedId::IK_ConstructorName: { 2028 TypeSourceInfo *TInfo; 2029 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2030 if (Ty.isNull()) 2031 return DeclarationNameInfo(); 2032 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2033 Context.getCanonicalType(Ty))); 2034 NameInfo.setLoc(Name.StartLocation); 2035 NameInfo.setNamedTypeInfo(TInfo); 2036 return NameInfo; 2037 } 2038 2039 case UnqualifiedId::IK_ConstructorTemplateId: { 2040 // In well-formed code, we can only have a constructor 2041 // template-id that refers to the current context, so go there 2042 // to find the actual type being constructed. 2043 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2044 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2045 return DeclarationNameInfo(); 2046 2047 // Determine the type of the class being constructed. 2048 QualType CurClassType = Context.getTypeDeclType(CurClass); 2049 2050 // FIXME: Check two things: that the template-id names the same type as 2051 // CurClassType, and that the template-id does not occur when the name 2052 // was qualified. 2053 2054 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2055 Context.getCanonicalType(CurClassType))); 2056 NameInfo.setLoc(Name.StartLocation); 2057 // FIXME: should we retrieve TypeSourceInfo? 2058 NameInfo.setNamedTypeInfo(0); 2059 return NameInfo; 2060 } 2061 2062 case UnqualifiedId::IK_DestructorName: { 2063 TypeSourceInfo *TInfo; 2064 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2065 if (Ty.isNull()) 2066 return DeclarationNameInfo(); 2067 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2068 Context.getCanonicalType(Ty))); 2069 NameInfo.setLoc(Name.StartLocation); 2070 NameInfo.setNamedTypeInfo(TInfo); 2071 return NameInfo; 2072 } 2073 2074 case UnqualifiedId::IK_TemplateId: { 2075 TemplateName TName = Name.TemplateId->Template.get(); 2076 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2077 return Context.getNameForTemplate(TName, TNameLoc); 2078 } 2079 2080 } // switch (Name.getKind()) 2081 2082 assert(false && "Unknown name kind"); 2083 return DeclarationNameInfo(); 2084} 2085 2086/// isNearlyMatchingFunction - Determine whether the C++ functions 2087/// Declaration and Definition are "nearly" matching. This heuristic 2088/// is used to improve diagnostics in the case where an out-of-line 2089/// function definition doesn't match any declaration within 2090/// the class or namespace. 2091static bool isNearlyMatchingFunction(ASTContext &Context, 2092 FunctionDecl *Declaration, 2093 FunctionDecl *Definition) { 2094 if (Declaration->param_size() != Definition->param_size()) 2095 return false; 2096 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2097 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2098 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2099 2100 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2101 DefParamTy.getNonReferenceType())) 2102 return false; 2103 } 2104 2105 return true; 2106} 2107 2108/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2109/// declarator needs to be rebuilt in the current instantiation. 2110/// Any bits of declarator which appear before the name are valid for 2111/// consideration here. That's specifically the type in the decl spec 2112/// and the base type in any member-pointer chunks. 2113static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2114 DeclarationName Name) { 2115 // The types we specifically need to rebuild are: 2116 // - typenames, typeofs, and decltypes 2117 // - types which will become injected class names 2118 // Of course, we also need to rebuild any type referencing such a 2119 // type. It's safest to just say "dependent", but we call out a 2120 // few cases here. 2121 2122 DeclSpec &DS = D.getMutableDeclSpec(); 2123 switch (DS.getTypeSpecType()) { 2124 case DeclSpec::TST_typename: 2125 case DeclSpec::TST_typeofType: 2126 case DeclSpec::TST_typeofExpr: 2127 case DeclSpec::TST_decltype: { 2128 // Grab the type from the parser. 2129 TypeSourceInfo *TSI = 0; 2130 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2131 if (T.isNull() || !T->isDependentType()) break; 2132 2133 // Make sure there's a type source info. This isn't really much 2134 // of a waste; most dependent types should have type source info 2135 // attached already. 2136 if (!TSI) 2137 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2138 2139 // Rebuild the type in the current instantiation. 2140 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2141 if (!TSI) return true; 2142 2143 // Store the new type back in the decl spec. 2144 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2145 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2146 break; 2147 } 2148 2149 default: 2150 // Nothing to do for these decl specs. 2151 break; 2152 } 2153 2154 // It doesn't matter what order we do this in. 2155 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2156 DeclaratorChunk &Chunk = D.getTypeObject(I); 2157 2158 // The only type information in the declarator which can come 2159 // before the declaration name is the base type of a member 2160 // pointer. 2161 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2162 continue; 2163 2164 // Rebuild the scope specifier in-place. 2165 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2166 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2167 return true; 2168 } 2169 2170 return false; 2171} 2172 2173Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2174 MultiTemplateParamsArg TemplateParamLists, 2175 bool IsFunctionDefinition) { 2176 // TODO: consider using NameInfo for diagnostic. 2177 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2178 DeclarationName Name = NameInfo.getName(); 2179 2180 // All of these full declarators require an identifier. If it doesn't have 2181 // one, the ParsedFreeStandingDeclSpec action should be used. 2182 if (!Name) { 2183 if (!D.isInvalidType()) // Reject this if we think it is valid. 2184 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2185 diag::err_declarator_need_ident) 2186 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2187 return 0; 2188 } 2189 2190 // The scope passed in may not be a decl scope. Zip up the scope tree until 2191 // we find one that is. 2192 while ((S->getFlags() & Scope::DeclScope) == 0 || 2193 (S->getFlags() & Scope::TemplateParamScope) != 0) 2194 S = S->getParent(); 2195 2196 DeclContext *DC = CurContext; 2197 if (D.getCXXScopeSpec().isInvalid()) 2198 D.setInvalidType(); 2199 else if (D.getCXXScopeSpec().isSet()) { 2200 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2201 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2202 if (!DC) { 2203 // If we could not compute the declaration context, it's because the 2204 // declaration context is dependent but does not refer to a class, 2205 // class template, or class template partial specialization. Complain 2206 // and return early, to avoid the coming semantic disaster. 2207 Diag(D.getIdentifierLoc(), 2208 diag::err_template_qualified_declarator_no_match) 2209 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2210 << D.getCXXScopeSpec().getRange(); 2211 return 0; 2212 } 2213 2214 bool IsDependentContext = DC->isDependentContext(); 2215 2216 if (!IsDependentContext && 2217 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2218 return 0; 2219 2220 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2221 Diag(D.getIdentifierLoc(), 2222 diag::err_member_def_undefined_record) 2223 << Name << DC << D.getCXXScopeSpec().getRange(); 2224 D.setInvalidType(); 2225 } 2226 2227 // Check whether we need to rebuild the type of the given 2228 // declaration in the current instantiation. 2229 if (EnteringContext && IsDependentContext && 2230 TemplateParamLists.size() != 0) { 2231 ContextRAII SavedContext(*this, DC); 2232 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2233 D.setInvalidType(); 2234 } 2235 } 2236 2237 NamedDecl *New; 2238 2239 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2240 QualType R = TInfo->getType(); 2241 2242 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2243 ForRedeclaration); 2244 2245 // See if this is a redefinition of a variable in the same scope. 2246 if (!D.getCXXScopeSpec().isSet()) { 2247 bool IsLinkageLookup = false; 2248 2249 // If the declaration we're planning to build will be a function 2250 // or object with linkage, then look for another declaration with 2251 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2252 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2253 /* Do nothing*/; 2254 else if (R->isFunctionType()) { 2255 if (CurContext->isFunctionOrMethod() || 2256 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2257 IsLinkageLookup = true; 2258 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2259 IsLinkageLookup = true; 2260 else if (CurContext->getLookupContext()->isTranslationUnit() && 2261 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2262 IsLinkageLookup = true; 2263 2264 if (IsLinkageLookup) 2265 Previous.clear(LookupRedeclarationWithLinkage); 2266 2267 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2268 } else { // Something like "int foo::x;" 2269 LookupQualifiedName(Previous, DC); 2270 2271 // Don't consider using declarations as previous declarations for 2272 // out-of-line members. 2273 RemoveUsingDecls(Previous); 2274 2275 // C++ 7.3.1.2p2: 2276 // Members (including explicit specializations of templates) of a named 2277 // namespace can also be defined outside that namespace by explicit 2278 // qualification of the name being defined, provided that the entity being 2279 // defined was already declared in the namespace and the definition appears 2280 // after the point of declaration in a namespace that encloses the 2281 // declarations namespace. 2282 // 2283 // Note that we only check the context at this point. We don't yet 2284 // have enough information to make sure that PrevDecl is actually 2285 // the declaration we want to match. For example, given: 2286 // 2287 // class X { 2288 // void f(); 2289 // void f(float); 2290 // }; 2291 // 2292 // void X::f(int) { } // ill-formed 2293 // 2294 // In this case, PrevDecl will point to the overload set 2295 // containing the two f's declared in X, but neither of them 2296 // matches. 2297 2298 // First check whether we named the global scope. 2299 if (isa<TranslationUnitDecl>(DC)) { 2300 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2301 << Name << D.getCXXScopeSpec().getRange(); 2302 } else { 2303 DeclContext *Cur = CurContext; 2304 while (isa<LinkageSpecDecl>(Cur)) 2305 Cur = Cur->getParent(); 2306 if (!Cur->Encloses(DC)) { 2307 // The qualifying scope doesn't enclose the original declaration. 2308 // Emit diagnostic based on current scope. 2309 SourceLocation L = D.getIdentifierLoc(); 2310 SourceRange R = D.getCXXScopeSpec().getRange(); 2311 if (isa<FunctionDecl>(Cur)) 2312 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2313 else 2314 Diag(L, diag::err_invalid_declarator_scope) 2315 << Name << cast<NamedDecl>(DC) << R; 2316 D.setInvalidType(); 2317 } 2318 } 2319 } 2320 2321 if (Previous.isSingleResult() && 2322 Previous.getFoundDecl()->isTemplateParameter()) { 2323 // Maybe we will complain about the shadowed template parameter. 2324 if (!D.isInvalidType()) 2325 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2326 Previous.getFoundDecl())) 2327 D.setInvalidType(); 2328 2329 // Just pretend that we didn't see the previous declaration. 2330 Previous.clear(); 2331 } 2332 2333 // In C++, the previous declaration we find might be a tag type 2334 // (class or enum). In this case, the new declaration will hide the 2335 // tag type. Note that this does does not apply if we're declaring a 2336 // typedef (C++ [dcl.typedef]p4). 2337 if (Previous.isSingleTagDecl() && 2338 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2339 Previous.clear(); 2340 2341 bool Redeclaration = false; 2342 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2343 if (TemplateParamLists.size()) { 2344 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2345 return 0; 2346 } 2347 2348 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2349 } else if (R->isFunctionType()) { 2350 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2351 move(TemplateParamLists), 2352 IsFunctionDefinition, Redeclaration); 2353 } else { 2354 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2355 move(TemplateParamLists), 2356 Redeclaration); 2357 } 2358 2359 if (New == 0) 2360 return 0; 2361 2362 // If this has an identifier and is not an invalid redeclaration or 2363 // function template specialization, add it to the scope stack. 2364 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2365 PushOnScopeChains(New, S); 2366 2367 return New; 2368} 2369 2370/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2371/// types into constant array types in certain situations which would otherwise 2372/// be errors (for GCC compatibility). 2373static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2374 ASTContext &Context, 2375 bool &SizeIsNegative, 2376 llvm::APSInt &Oversized) { 2377 // This method tries to turn a variable array into a constant 2378 // array even when the size isn't an ICE. This is necessary 2379 // for compatibility with code that depends on gcc's buggy 2380 // constant expression folding, like struct {char x[(int)(char*)2];} 2381 SizeIsNegative = false; 2382 Oversized = 0; 2383 2384 if (T->isDependentType()) 2385 return QualType(); 2386 2387 QualifierCollector Qs; 2388 const Type *Ty = Qs.strip(T); 2389 2390 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2391 QualType Pointee = PTy->getPointeeType(); 2392 QualType FixedType = 2393 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2394 Oversized); 2395 if (FixedType.isNull()) return FixedType; 2396 FixedType = Context.getPointerType(FixedType); 2397 return Qs.apply(FixedType); 2398 } 2399 2400 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2401 if (!VLATy) 2402 return QualType(); 2403 // FIXME: We should probably handle this case 2404 if (VLATy->getElementType()->isVariablyModifiedType()) 2405 return QualType(); 2406 2407 Expr::EvalResult EvalResult; 2408 if (!VLATy->getSizeExpr() || 2409 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2410 !EvalResult.Val.isInt()) 2411 return QualType(); 2412 2413 // Check whether the array size is negative. 2414 llvm::APSInt &Res = EvalResult.Val.getInt(); 2415 if (Res.isSigned() && Res.isNegative()) { 2416 SizeIsNegative = true; 2417 return QualType(); 2418 } 2419 2420 // Check whether the array is too large to be addressed. 2421 unsigned ActiveSizeBits 2422 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2423 Res); 2424 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2425 Oversized = Res; 2426 return QualType(); 2427 } 2428 2429 return Context.getConstantArrayType(VLATy->getElementType(), 2430 Res, ArrayType::Normal, 0); 2431} 2432 2433/// \brief Register the given locally-scoped external C declaration so 2434/// that it can be found later for redeclarations 2435void 2436Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2437 const LookupResult &Previous, 2438 Scope *S) { 2439 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2440 "Decl is not a locally-scoped decl!"); 2441 // Note that we have a locally-scoped external with this name. 2442 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2443 2444 if (!Previous.isSingleResult()) 2445 return; 2446 2447 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2448 2449 // If there was a previous declaration of this variable, it may be 2450 // in our identifier chain. Update the identifier chain with the new 2451 // declaration. 2452 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2453 // The previous declaration was found on the identifer resolver 2454 // chain, so remove it from its scope. 2455 while (S && !S->isDeclScope(PrevDecl)) 2456 S = S->getParent(); 2457 2458 if (S) 2459 S->RemoveDecl(PrevDecl); 2460 } 2461} 2462 2463/// \brief Diagnose function specifiers on a declaration of an identifier that 2464/// does not identify a function. 2465void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2466 // FIXME: We should probably indicate the identifier in question to avoid 2467 // confusion for constructs like "inline int a(), b;" 2468 if (D.getDeclSpec().isInlineSpecified()) 2469 Diag(D.getDeclSpec().getInlineSpecLoc(), 2470 diag::err_inline_non_function); 2471 2472 if (D.getDeclSpec().isVirtualSpecified()) 2473 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2474 diag::err_virtual_non_function); 2475 2476 if (D.getDeclSpec().isExplicitSpecified()) 2477 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2478 diag::err_explicit_non_function); 2479} 2480 2481NamedDecl* 2482Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2483 QualType R, TypeSourceInfo *TInfo, 2484 LookupResult &Previous, bool &Redeclaration) { 2485 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2486 if (D.getCXXScopeSpec().isSet()) { 2487 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2488 << D.getCXXScopeSpec().getRange(); 2489 D.setInvalidType(); 2490 // Pretend we didn't see the scope specifier. 2491 DC = CurContext; 2492 Previous.clear(); 2493 } 2494 2495 if (getLangOptions().CPlusPlus) { 2496 // Check that there are no default arguments (C++ only). 2497 CheckExtraCXXDefaultArguments(D); 2498 } 2499 2500 DiagnoseFunctionSpecifiers(D); 2501 2502 if (D.getDeclSpec().isThreadSpecified()) 2503 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2504 2505 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2506 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2507 << D.getName().getSourceRange(); 2508 return 0; 2509 } 2510 2511 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2512 if (!NewTD) return 0; 2513 2514 // Handle attributes prior to checking for duplicates in MergeVarDecl 2515 ProcessDeclAttributes(S, NewTD, D); 2516 2517 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2518 // then it shall have block scope. 2519 // Note that variably modified types must be fixed before merging the decl so 2520 // that redeclarations will match. 2521 QualType T = NewTD->getUnderlyingType(); 2522 if (T->isVariablyModifiedType()) { 2523 setFunctionHasBranchProtectedScope(); 2524 2525 if (S->getFnParent() == 0) { 2526 bool SizeIsNegative; 2527 llvm::APSInt Oversized; 2528 QualType FixedTy = 2529 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2530 Oversized); 2531 if (!FixedTy.isNull()) { 2532 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2533 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2534 } else { 2535 if (SizeIsNegative) 2536 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2537 else if (T->isVariableArrayType()) 2538 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2539 else if (Oversized.getBoolValue()) 2540 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2541 << Oversized.toString(10); 2542 else 2543 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2544 NewTD->setInvalidDecl(); 2545 } 2546 } 2547 } 2548 2549 // Merge the decl with the existing one if appropriate. If the decl is 2550 // in an outer scope, it isn't the same thing. 2551 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2552 if (!Previous.empty()) { 2553 Redeclaration = true; 2554 MergeTypeDefDecl(NewTD, Previous); 2555 } 2556 2557 // If this is the C FILE type, notify the AST context. 2558 if (IdentifierInfo *II = NewTD->getIdentifier()) 2559 if (!NewTD->isInvalidDecl() && 2560 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2561 if (II->isStr("FILE")) 2562 Context.setFILEDecl(NewTD); 2563 else if (II->isStr("jmp_buf")) 2564 Context.setjmp_bufDecl(NewTD); 2565 else if (II->isStr("sigjmp_buf")) 2566 Context.setsigjmp_bufDecl(NewTD); 2567 } 2568 2569 return NewTD; 2570} 2571 2572/// \brief Determines whether the given declaration is an out-of-scope 2573/// previous declaration. 2574/// 2575/// This routine should be invoked when name lookup has found a 2576/// previous declaration (PrevDecl) that is not in the scope where a 2577/// new declaration by the same name is being introduced. If the new 2578/// declaration occurs in a local scope, previous declarations with 2579/// linkage may still be considered previous declarations (C99 2580/// 6.2.2p4-5, C++ [basic.link]p6). 2581/// 2582/// \param PrevDecl the previous declaration found by name 2583/// lookup 2584/// 2585/// \param DC the context in which the new declaration is being 2586/// declared. 2587/// 2588/// \returns true if PrevDecl is an out-of-scope previous declaration 2589/// for a new delcaration with the same name. 2590static bool 2591isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2592 ASTContext &Context) { 2593 if (!PrevDecl) 2594 return 0; 2595 2596 if (!PrevDecl->hasLinkage()) 2597 return false; 2598 2599 if (Context.getLangOptions().CPlusPlus) { 2600 // C++ [basic.link]p6: 2601 // If there is a visible declaration of an entity with linkage 2602 // having the same name and type, ignoring entities declared 2603 // outside the innermost enclosing namespace scope, the block 2604 // scope declaration declares that same entity and receives the 2605 // linkage of the previous declaration. 2606 DeclContext *OuterContext = DC->getLookupContext(); 2607 if (!OuterContext->isFunctionOrMethod()) 2608 // This rule only applies to block-scope declarations. 2609 return false; 2610 else { 2611 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2612 if (PrevOuterContext->isRecord()) 2613 // We found a member function: ignore it. 2614 return false; 2615 else { 2616 // Find the innermost enclosing namespace for the new and 2617 // previous declarations. 2618 while (!OuterContext->isFileContext()) 2619 OuterContext = OuterContext->getParent(); 2620 while (!PrevOuterContext->isFileContext()) 2621 PrevOuterContext = PrevOuterContext->getParent(); 2622 2623 // The previous declaration is in a different namespace, so it 2624 // isn't the same function. 2625 if (OuterContext->getPrimaryContext() != 2626 PrevOuterContext->getPrimaryContext()) 2627 return false; 2628 } 2629 } 2630 } 2631 2632 return true; 2633} 2634 2635static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2636 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2637 if (!SS.isSet()) return; 2638 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2639 SS.getRange()); 2640} 2641 2642NamedDecl* 2643Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2644 QualType R, TypeSourceInfo *TInfo, 2645 LookupResult &Previous, 2646 MultiTemplateParamsArg TemplateParamLists, 2647 bool &Redeclaration) { 2648 DeclarationName Name = GetNameForDeclarator(D).getName(); 2649 2650 // Check that there are no default arguments (C++ only). 2651 if (getLangOptions().CPlusPlus) 2652 CheckExtraCXXDefaultArguments(D); 2653 2654 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2655 assert(SCSpec != DeclSpec::SCS_typedef && 2656 "Parser allowed 'typedef' as storage class VarDecl."); 2657 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2658 if (SCSpec == DeclSpec::SCS_mutable) { 2659 // mutable can only appear on non-static class members, so it's always 2660 // an error here 2661 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2662 D.setInvalidType(); 2663 SC = VarDecl::None; 2664 } 2665 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2666 VarDecl::StorageClass SCAsWritten 2667 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2668 2669 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2670 if (!II) { 2671 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2672 << Name.getAsString(); 2673 return 0; 2674 } 2675 2676 DiagnoseFunctionSpecifiers(D); 2677 2678 if (!DC->isRecord() && S->getFnParent() == 0) { 2679 // C99 6.9p2: The storage-class specifiers auto and register shall not 2680 // appear in the declaration specifiers in an external declaration. 2681 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2682 2683 // If this is a register variable with an asm label specified, then this 2684 // is a GNU extension. 2685 if (SC == VarDecl::Register && D.getAsmLabel()) 2686 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2687 else 2688 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2689 D.setInvalidType(); 2690 } 2691 } 2692 if (DC->isRecord() && !CurContext->isRecord()) { 2693 // This is an out-of-line definition of a static data member. 2694 if (SC == VarDecl::Static) { 2695 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2696 diag::err_static_out_of_line) 2697 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2698 } else if (SC == VarDecl::None) 2699 SC = VarDecl::Static; 2700 } 2701 if (SC == VarDecl::Static) { 2702 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2703 if (RD->isLocalClass()) 2704 Diag(D.getIdentifierLoc(), 2705 diag::err_static_data_member_not_allowed_in_local_class) 2706 << Name << RD->getDeclName(); 2707 } 2708 } 2709 2710 // Match up the template parameter lists with the scope specifier, then 2711 // determine whether we have a template or a template specialization. 2712 bool isExplicitSpecialization = false; 2713 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2714 bool Invalid = false; 2715 if (TemplateParameterList *TemplateParams 2716 = MatchTemplateParametersToScopeSpecifier( 2717 D.getDeclSpec().getSourceRange().getBegin(), 2718 D.getCXXScopeSpec(), 2719 (TemplateParameterList**)TemplateParamLists.get(), 2720 TemplateParamLists.size(), 2721 /*never a friend*/ false, 2722 isExplicitSpecialization, 2723 Invalid)) { 2724 // All but one template parameter lists have been matching. 2725 --NumMatchedTemplateParamLists; 2726 2727 if (TemplateParams->size() > 0) { 2728 // There is no such thing as a variable template. 2729 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2730 << II 2731 << SourceRange(TemplateParams->getTemplateLoc(), 2732 TemplateParams->getRAngleLoc()); 2733 return 0; 2734 } else { 2735 // There is an extraneous 'template<>' for this variable. Complain 2736 // about it, but allow the declaration of the variable. 2737 Diag(TemplateParams->getTemplateLoc(), 2738 diag::err_template_variable_noparams) 2739 << II 2740 << SourceRange(TemplateParams->getTemplateLoc(), 2741 TemplateParams->getRAngleLoc()); 2742 2743 isExplicitSpecialization = true; 2744 } 2745 } 2746 2747 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2748 II, R, TInfo, SC, SCAsWritten); 2749 2750 if (D.isInvalidType() || Invalid) 2751 NewVD->setInvalidDecl(); 2752 2753 SetNestedNameSpecifier(NewVD, D); 2754 2755 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2756 NewVD->setTemplateParameterListsInfo(Context, 2757 NumMatchedTemplateParamLists, 2758 (TemplateParameterList**)TemplateParamLists.release()); 2759 } 2760 2761 if (D.getDeclSpec().isThreadSpecified()) { 2762 if (NewVD->hasLocalStorage()) 2763 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2764 else if (!Context.Target.isTLSSupported()) 2765 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2766 else 2767 NewVD->setThreadSpecified(true); 2768 } 2769 2770 // Set the lexical context. If the declarator has a C++ scope specifier, the 2771 // lexical context will be different from the semantic context. 2772 NewVD->setLexicalDeclContext(CurContext); 2773 2774 // Handle attributes prior to checking for duplicates in MergeVarDecl 2775 ProcessDeclAttributes(S, NewVD, D); 2776 2777 // Handle GNU asm-label extension (encoded as an attribute). 2778 if (Expr *E = (Expr*) D.getAsmLabel()) { 2779 // The parser guarantees this is a string. 2780 StringLiteral *SE = cast<StringLiteral>(E); 2781 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 2782 Context, SE->getString())); 2783 } 2784 2785 // Diagnose shadowed variables before filtering for scope. 2786 if (!D.getCXXScopeSpec().isSet()) 2787 CheckShadow(S, NewVD, Previous); 2788 2789 // Don't consider existing declarations that are in a different 2790 // scope and are out-of-semantic-context declarations (if the new 2791 // declaration has linkage). 2792 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2793 2794 // Merge the decl with the existing one if appropriate. 2795 if (!Previous.empty()) { 2796 if (Previous.isSingleResult() && 2797 isa<FieldDecl>(Previous.getFoundDecl()) && 2798 D.getCXXScopeSpec().isSet()) { 2799 // The user tried to define a non-static data member 2800 // out-of-line (C++ [dcl.meaning]p1). 2801 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2802 << D.getCXXScopeSpec().getRange(); 2803 Previous.clear(); 2804 NewVD->setInvalidDecl(); 2805 } 2806 } else if (D.getCXXScopeSpec().isSet()) { 2807 // No previous declaration in the qualifying scope. 2808 Diag(D.getIdentifierLoc(), diag::err_no_member) 2809 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2810 << D.getCXXScopeSpec().getRange(); 2811 NewVD->setInvalidDecl(); 2812 } 2813 2814 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2815 2816 // This is an explicit specialization of a static data member. Check it. 2817 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2818 CheckMemberSpecialization(NewVD, Previous)) 2819 NewVD->setInvalidDecl(); 2820 2821 // attributes declared post-definition are currently ignored 2822 // FIXME: This should be handled in attribute merging, not 2823 // here. 2824 if (Previous.isSingleResult()) { 2825 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2826 if (Def && (Def = Def->getDefinition()) && 2827 Def != NewVD && D.hasAttributes()) { 2828 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2829 Diag(Def->getLocation(), diag::note_previous_definition); 2830 } 2831 } 2832 2833 // If this is a locally-scoped extern C variable, update the map of 2834 // such variables. 2835 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2836 !NewVD->isInvalidDecl()) 2837 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2838 2839 // If there's a #pragma GCC visibility in scope, and this isn't a class 2840 // member, set the visibility of this variable. 2841 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2842 AddPushedVisibilityAttribute(NewVD); 2843 2844 MarkUnusedFileScopedDecl(NewVD); 2845 2846 return NewVD; 2847} 2848 2849/// \brief Diagnose variable or built-in function shadowing. Implements 2850/// -Wshadow. 2851/// 2852/// This method is called whenever a VarDecl is added to a "useful" 2853/// scope. 2854/// 2855/// \param S the scope in which the shadowing name is being declared 2856/// \param R the lookup of the name 2857/// 2858void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2859 // Return if warning is ignored. 2860 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2861 return; 2862 2863 // Don't diagnose declarations at file scope. The scope might not 2864 // have a DeclContext if (e.g.) we're parsing a function prototype. 2865 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2866 if (NewDC && NewDC->isFileContext()) 2867 return; 2868 2869 // Only diagnose if we're shadowing an unambiguous field or variable. 2870 if (R.getResultKind() != LookupResult::Found) 2871 return; 2872 2873 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2874 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2875 return; 2876 2877 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2878 2879 // Only warn about certain kinds of shadowing for class members. 2880 if (NewDC && NewDC->isRecord()) { 2881 // In particular, don't warn about shadowing non-class members. 2882 if (!OldDC->isRecord()) 2883 return; 2884 2885 // TODO: should we warn about static data members shadowing 2886 // static data members from base classes? 2887 2888 // TODO: don't diagnose for inaccessible shadowed members. 2889 // This is hard to do perfectly because we might friend the 2890 // shadowing context, but that's just a false negative. 2891 } 2892 2893 // Determine what kind of declaration we're shadowing. 2894 unsigned Kind; 2895 if (isa<RecordDecl>(OldDC)) { 2896 if (isa<FieldDecl>(ShadowedDecl)) 2897 Kind = 3; // field 2898 else 2899 Kind = 2; // static data member 2900 } else if (OldDC->isFileContext()) 2901 Kind = 1; // global 2902 else 2903 Kind = 0; // local 2904 2905 DeclarationName Name = R.getLookupName(); 2906 2907 // Emit warning and note. 2908 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2909 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2910} 2911 2912/// \brief Check -Wshadow without the advantage of a previous lookup. 2913void Sema::CheckShadow(Scope *S, VarDecl *D) { 2914 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2915 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2916 LookupName(R, S); 2917 CheckShadow(S, D, R); 2918} 2919 2920/// \brief Perform semantic checking on a newly-created variable 2921/// declaration. 2922/// 2923/// This routine performs all of the type-checking required for a 2924/// variable declaration once it has been built. It is used both to 2925/// check variables after they have been parsed and their declarators 2926/// have been translated into a declaration, and to check variables 2927/// that have been instantiated from a template. 2928/// 2929/// Sets NewVD->isInvalidDecl() if an error was encountered. 2930void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2931 LookupResult &Previous, 2932 bool &Redeclaration) { 2933 // If the decl is already known invalid, don't check it. 2934 if (NewVD->isInvalidDecl()) 2935 return; 2936 2937 QualType T = NewVD->getType(); 2938 2939 if (T->isObjCObjectType()) { 2940 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2941 return NewVD->setInvalidDecl(); 2942 } 2943 2944 // Emit an error if an address space was applied to decl with local storage. 2945 // This includes arrays of objects with address space qualifiers, but not 2946 // automatic variables that point to other address spaces. 2947 // ISO/IEC TR 18037 S5.1.2 2948 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2949 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2950 return NewVD->setInvalidDecl(); 2951 } 2952 2953 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2954 && !NewVD->hasAttr<BlocksAttr>()) 2955 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2956 2957 bool isVM = T->isVariablyModifiedType(); 2958 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2959 NewVD->hasAttr<BlocksAttr>()) 2960 setFunctionHasBranchProtectedScope(); 2961 2962 if ((isVM && NewVD->hasLinkage()) || 2963 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2964 bool SizeIsNegative; 2965 llvm::APSInt Oversized; 2966 QualType FixedTy = 2967 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2968 Oversized); 2969 2970 if (FixedTy.isNull() && T->isVariableArrayType()) { 2971 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2972 // FIXME: This won't give the correct result for 2973 // int a[10][n]; 2974 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2975 2976 if (NewVD->isFileVarDecl()) 2977 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2978 << SizeRange; 2979 else if (NewVD->getStorageClass() == VarDecl::Static) 2980 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2981 << SizeRange; 2982 else 2983 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2984 << SizeRange; 2985 return NewVD->setInvalidDecl(); 2986 } 2987 2988 if (FixedTy.isNull()) { 2989 if (NewVD->isFileVarDecl()) 2990 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2991 else 2992 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2993 return NewVD->setInvalidDecl(); 2994 } 2995 2996 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2997 NewVD->setType(FixedTy); 2998 } 2999 3000 if (Previous.empty() && NewVD->isExternC()) { 3001 // Since we did not find anything by this name and we're declaring 3002 // an extern "C" variable, look for a non-visible extern "C" 3003 // declaration with the same name. 3004 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3005 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3006 if (Pos != LocallyScopedExternalDecls.end()) 3007 Previous.addDecl(Pos->second); 3008 } 3009 3010 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3011 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3012 << T; 3013 return NewVD->setInvalidDecl(); 3014 } 3015 3016 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3017 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3018 return NewVD->setInvalidDecl(); 3019 } 3020 3021 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3022 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3023 return NewVD->setInvalidDecl(); 3024 } 3025 3026 // Function pointers and references cannot have qualified function type, only 3027 // function pointer-to-members can do that. 3028 QualType Pointee; 3029 unsigned PtrOrRef = 0; 3030 if (const PointerType *Ptr = T->getAs<PointerType>()) 3031 Pointee = Ptr->getPointeeType(); 3032 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3033 Pointee = Ref->getPointeeType(); 3034 PtrOrRef = 1; 3035 } 3036 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3037 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3038 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3039 << PtrOrRef; 3040 return NewVD->setInvalidDecl(); 3041 } 3042 3043 if (!Previous.empty()) { 3044 Redeclaration = true; 3045 MergeVarDecl(NewVD, Previous); 3046 } 3047} 3048 3049/// \brief Data used with FindOverriddenMethod 3050struct FindOverriddenMethodData { 3051 Sema *S; 3052 CXXMethodDecl *Method; 3053}; 3054 3055/// \brief Member lookup function that determines whether a given C++ 3056/// method overrides a method in a base class, to be used with 3057/// CXXRecordDecl::lookupInBases(). 3058static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3059 CXXBasePath &Path, 3060 void *UserData) { 3061 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3062 3063 FindOverriddenMethodData *Data 3064 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3065 3066 DeclarationName Name = Data->Method->getDeclName(); 3067 3068 // FIXME: Do we care about other names here too? 3069 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3070 // We really want to find the base class destructor here. 3071 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3072 CanQualType CT = Data->S->Context.getCanonicalType(T); 3073 3074 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3075 } 3076 3077 for (Path.Decls = BaseRecord->lookup(Name); 3078 Path.Decls.first != Path.Decls.second; 3079 ++Path.Decls.first) { 3080 NamedDecl *D = *Path.Decls.first; 3081 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3082 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3083 return true; 3084 } 3085 } 3086 3087 return false; 3088} 3089 3090/// AddOverriddenMethods - See if a method overrides any in the base classes, 3091/// and if so, check that it's a valid override and remember it. 3092void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3093 // Look for virtual methods in base classes that this method might override. 3094 CXXBasePaths Paths; 3095 FindOverriddenMethodData Data; 3096 Data.Method = MD; 3097 Data.S = this; 3098 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3099 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3100 E = Paths.found_decls_end(); I != E; ++I) { 3101 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3102 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3103 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3104 !CheckOverridingFunctionAttributes(MD, OldMD)) 3105 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3106 } 3107 } 3108 } 3109} 3110 3111NamedDecl* 3112Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3113 QualType R, TypeSourceInfo *TInfo, 3114 LookupResult &Previous, 3115 MultiTemplateParamsArg TemplateParamLists, 3116 bool IsFunctionDefinition, bool &Redeclaration) { 3117 assert(R.getTypePtr()->isFunctionType()); 3118 3119 // TODO: consider using NameInfo for diagnostic. 3120 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3121 DeclarationName Name = NameInfo.getName(); 3122 FunctionDecl::StorageClass SC = FunctionDecl::None; 3123 switch (D.getDeclSpec().getStorageClassSpec()) { 3124 default: assert(0 && "Unknown storage class!"); 3125 case DeclSpec::SCS_auto: 3126 case DeclSpec::SCS_register: 3127 case DeclSpec::SCS_mutable: 3128 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3129 diag::err_typecheck_sclass_func); 3130 D.setInvalidType(); 3131 break; 3132 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 3133 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 3134 case DeclSpec::SCS_static: { 3135 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 3136 // C99 6.7.1p5: 3137 // The declaration of an identifier for a function that has 3138 // block scope shall have no explicit storage-class specifier 3139 // other than extern 3140 // See also (C++ [dcl.stc]p4). 3141 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3142 diag::err_static_block_func); 3143 SC = FunctionDecl::None; 3144 } else 3145 SC = FunctionDecl::Static; 3146 break; 3147 } 3148 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 3149 } 3150 3151 if (D.getDeclSpec().isThreadSpecified()) 3152 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3153 3154 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3155 bool isInline = D.getDeclSpec().isInlineSpecified(); 3156 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3157 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3158 3159 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3160 FunctionDecl::StorageClass SCAsWritten 3161 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3162 3163 // Check that the return type is not an abstract class type. 3164 // For record types, this is done by the AbstractClassUsageDiagnoser once 3165 // the class has been completely parsed. 3166 if (!DC->isRecord() && 3167 RequireNonAbstractType(D.getIdentifierLoc(), 3168 R->getAs<FunctionType>()->getResultType(), 3169 diag::err_abstract_type_in_decl, 3170 AbstractReturnType)) 3171 D.setInvalidType(); 3172 3173 // Do not allow returning a objc interface by-value. 3174 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3175 Diag(D.getIdentifierLoc(), 3176 diag::err_object_cannot_be_passed_returned_by_value) << 0 3177 << R->getAs<FunctionType>()->getResultType(); 3178 D.setInvalidType(); 3179 } 3180 3181 bool isVirtualOkay = false; 3182 FunctionDecl *NewFD; 3183 3184 if (isFriend) { 3185 // C++ [class.friend]p5 3186 // A function can be defined in a friend declaration of a 3187 // class . . . . Such a function is implicitly inline. 3188 isInline |= IsFunctionDefinition; 3189 } 3190 3191 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3192 // This is a C++ constructor declaration. 3193 assert(DC->isRecord() && 3194 "Constructors can only be declared in a member context"); 3195 3196 R = CheckConstructorDeclarator(D, R, SC); 3197 3198 // Create the new declaration 3199 NewFD = CXXConstructorDecl::Create(Context, 3200 cast<CXXRecordDecl>(DC), 3201 NameInfo, R, TInfo, 3202 isExplicit, isInline, 3203 /*isImplicitlyDeclared=*/false); 3204 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3205 // This is a C++ destructor declaration. 3206 if (DC->isRecord()) { 3207 R = CheckDestructorDeclarator(D, R, SC); 3208 3209 NewFD = CXXDestructorDecl::Create(Context, 3210 cast<CXXRecordDecl>(DC), 3211 NameInfo, R, 3212 isInline, 3213 /*isImplicitlyDeclared=*/false); 3214 NewFD->setTypeSourceInfo(TInfo); 3215 3216 isVirtualOkay = true; 3217 } else { 3218 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3219 3220 // Create a FunctionDecl to satisfy the function definition parsing 3221 // code path. 3222 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3223 Name, R, TInfo, SC, SCAsWritten, isInline, 3224 /*hasPrototype=*/true); 3225 D.setInvalidType(); 3226 } 3227 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3228 if (!DC->isRecord()) { 3229 Diag(D.getIdentifierLoc(), 3230 diag::err_conv_function_not_member); 3231 return 0; 3232 } 3233 3234 CheckConversionDeclarator(D, R, SC); 3235 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3236 NameInfo, R, TInfo, 3237 isInline, isExplicit); 3238 3239 isVirtualOkay = true; 3240 } else if (DC->isRecord()) { 3241 // If the of the function is the same as the name of the record, then this 3242 // must be an invalid constructor that has a return type. 3243 // (The parser checks for a return type and makes the declarator a 3244 // constructor if it has no return type). 3245 // must have an invalid constructor that has a return type 3246 if (Name.getAsIdentifierInfo() && 3247 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3248 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3249 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3250 << SourceRange(D.getIdentifierLoc()); 3251 return 0; 3252 } 3253 3254 bool isStatic = SC == FunctionDecl::Static; 3255 3256 // [class.free]p1: 3257 // Any allocation function for a class T is a static member 3258 // (even if not explicitly declared static). 3259 if (Name.getCXXOverloadedOperator() == OO_New || 3260 Name.getCXXOverloadedOperator() == OO_Array_New) 3261 isStatic = true; 3262 3263 // [class.free]p6 Any deallocation function for a class X is a static member 3264 // (even if not explicitly declared static). 3265 if (Name.getCXXOverloadedOperator() == OO_Delete || 3266 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3267 isStatic = true; 3268 3269 // This is a C++ method declaration. 3270 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3271 NameInfo, R, TInfo, 3272 isStatic, SCAsWritten, isInline); 3273 3274 isVirtualOkay = !isStatic; 3275 } else { 3276 // Determine whether the function was written with a 3277 // prototype. This true when: 3278 // - we're in C++ (where every function has a prototype), 3279 // - there is a prototype in the declarator, or 3280 // - the type R of the function is some kind of typedef or other reference 3281 // to a type name (which eventually refers to a function type). 3282 bool HasPrototype = 3283 getLangOptions().CPlusPlus || 3284 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3285 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3286 3287 NewFD = FunctionDecl::Create(Context, DC, 3288 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3289 HasPrototype); 3290 } 3291 3292 if (D.isInvalidType()) 3293 NewFD->setInvalidDecl(); 3294 3295 SetNestedNameSpecifier(NewFD, D); 3296 3297 // Set the lexical context. If the declarator has a C++ 3298 // scope specifier, or is the object of a friend declaration, the 3299 // lexical context will be different from the semantic context. 3300 NewFD->setLexicalDeclContext(CurContext); 3301 3302 // Match up the template parameter lists with the scope specifier, then 3303 // determine whether we have a template or a template specialization. 3304 FunctionTemplateDecl *FunctionTemplate = 0; 3305 bool isExplicitSpecialization = false; 3306 bool isFunctionTemplateSpecialization = false; 3307 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3308 bool Invalid = false; 3309 if (TemplateParameterList *TemplateParams 3310 = MatchTemplateParametersToScopeSpecifier( 3311 D.getDeclSpec().getSourceRange().getBegin(), 3312 D.getCXXScopeSpec(), 3313 (TemplateParameterList**)TemplateParamLists.get(), 3314 TemplateParamLists.size(), 3315 isFriend, 3316 isExplicitSpecialization, 3317 Invalid)) { 3318 // All but one template parameter lists have been matching. 3319 --NumMatchedTemplateParamLists; 3320 3321 if (TemplateParams->size() > 0) { 3322 // This is a function template 3323 3324 // Check that we can declare a template here. 3325 if (CheckTemplateDeclScope(S, TemplateParams)) 3326 return 0; 3327 3328 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3329 NewFD->getLocation(), 3330 Name, TemplateParams, 3331 NewFD); 3332 FunctionTemplate->setLexicalDeclContext(CurContext); 3333 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3334 } else { 3335 // This is a function template specialization. 3336 isFunctionTemplateSpecialization = true; 3337 3338 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3339 if (isFriend && isFunctionTemplateSpecialization) { 3340 // We want to remove the "template<>", found here. 3341 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3342 3343 // If we remove the template<> and the name is not a 3344 // template-id, we're actually silently creating a problem: 3345 // the friend declaration will refer to an untemplated decl, 3346 // and clearly the user wants a template specialization. So 3347 // we need to insert '<>' after the name. 3348 SourceLocation InsertLoc; 3349 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3350 InsertLoc = D.getName().getSourceRange().getEnd(); 3351 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3352 } 3353 3354 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3355 << Name << RemoveRange 3356 << FixItHint::CreateRemoval(RemoveRange) 3357 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3358 } 3359 } 3360 } 3361 3362 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3363 NewFD->setTemplateParameterListsInfo(Context, 3364 NumMatchedTemplateParamLists, 3365 (TemplateParameterList**)TemplateParamLists.release()); 3366 } 3367 3368 if (Invalid) { 3369 NewFD->setInvalidDecl(); 3370 if (FunctionTemplate) 3371 FunctionTemplate->setInvalidDecl(); 3372 } 3373 3374 // C++ [dcl.fct.spec]p5: 3375 // The virtual specifier shall only be used in declarations of 3376 // nonstatic class member functions that appear within a 3377 // member-specification of a class declaration; see 10.3. 3378 // 3379 if (isVirtual && !NewFD->isInvalidDecl()) { 3380 if (!isVirtualOkay) { 3381 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3382 diag::err_virtual_non_function); 3383 } else if (!CurContext->isRecord()) { 3384 // 'virtual' was specified outside of the class. 3385 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3386 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3387 } else { 3388 // Okay: Add virtual to the method. 3389 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3390 CurClass->setMethodAsVirtual(NewFD); 3391 } 3392 } 3393 3394 // C++ [dcl.fct.spec]p3: 3395 // The inline specifier shall not appear on a block scope function declaration. 3396 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3397 if (CurContext->isFunctionOrMethod()) { 3398 // 'inline' is not allowed on block scope function declaration. 3399 Diag(D.getDeclSpec().getInlineSpecLoc(), 3400 diag::err_inline_declaration_block_scope) << Name 3401 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3402 } 3403 } 3404 3405 // C++ [dcl.fct.spec]p6: 3406 // The explicit specifier shall be used only in the declaration of a 3407 // constructor or conversion function within its class definition; see 12.3.1 3408 // and 12.3.2. 3409 if (isExplicit && !NewFD->isInvalidDecl()) { 3410 if (!CurContext->isRecord()) { 3411 // 'explicit' was specified outside of the class. 3412 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3413 diag::err_explicit_out_of_class) 3414 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3415 } else if (!isa<CXXConstructorDecl>(NewFD) && 3416 !isa<CXXConversionDecl>(NewFD)) { 3417 // 'explicit' was specified on a function that wasn't a constructor 3418 // or conversion function. 3419 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3420 diag::err_explicit_non_ctor_or_conv_function) 3421 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3422 } 3423 } 3424 3425 // Filter out previous declarations that don't match the scope. 3426 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3427 3428 if (isFriend) { 3429 // DC is the namespace in which the function is being declared. 3430 assert((DC->isFileContext() || !Previous.empty()) && 3431 "previously-undeclared friend function being created " 3432 "in a non-namespace context"); 3433 3434 // For now, claim that the objects have no previous declaration. 3435 if (FunctionTemplate) { 3436 FunctionTemplate->setObjectOfFriendDecl(false); 3437 FunctionTemplate->setAccess(AS_public); 3438 } 3439 NewFD->setObjectOfFriendDecl(false); 3440 NewFD->setAccess(AS_public); 3441 } 3442 3443 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3444 !CurContext->isRecord()) { 3445 // C++ [class.static]p1: 3446 // A data or function member of a class may be declared static 3447 // in a class definition, in which case it is a static member of 3448 // the class. 3449 3450 // Complain about the 'static' specifier if it's on an out-of-line 3451 // member function definition. 3452 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3453 diag::err_static_out_of_line) 3454 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3455 } 3456 3457 // Handle GNU asm-label extension (encoded as an attribute). 3458 if (Expr *E = (Expr*) D.getAsmLabel()) { 3459 // The parser guarantees this is a string. 3460 StringLiteral *SE = cast<StringLiteral>(E); 3461 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3462 SE->getString())); 3463 } 3464 3465 // Copy the parameter declarations from the declarator D to the function 3466 // declaration NewFD, if they are available. First scavenge them into Params. 3467 llvm::SmallVector<ParmVarDecl*, 16> Params; 3468 if (D.getNumTypeObjects() > 0) { 3469 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3470 3471 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3472 // function that takes no arguments, not a function that takes a 3473 // single void argument. 3474 // We let through "const void" here because Sema::GetTypeForDeclarator 3475 // already checks for that case. 3476 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3477 FTI.ArgInfo[0].Param && 3478 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3479 // Empty arg list, don't push any params. 3480 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3481 3482 // In C++, the empty parameter-type-list must be spelled "void"; a 3483 // typedef of void is not permitted. 3484 if (getLangOptions().CPlusPlus && 3485 Param->getType().getUnqualifiedType() != Context.VoidTy) 3486 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3487 // FIXME: Leaks decl? 3488 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3489 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3490 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3491 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3492 Param->setDeclContext(NewFD); 3493 Params.push_back(Param); 3494 3495 if (Param->isInvalidDecl()) 3496 NewFD->setInvalidDecl(); 3497 } 3498 } 3499 3500 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3501 // When we're declaring a function with a typedef, typeof, etc as in the 3502 // following example, we'll need to synthesize (unnamed) 3503 // parameters for use in the declaration. 3504 // 3505 // @code 3506 // typedef void fn(int); 3507 // fn f; 3508 // @endcode 3509 3510 // Synthesize a parameter for each argument type. 3511 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3512 AE = FT->arg_type_end(); AI != AE; ++AI) { 3513 ParmVarDecl *Param = 3514 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3515 Params.push_back(Param); 3516 } 3517 } else { 3518 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3519 "Should not need args for typedef of non-prototype fn"); 3520 } 3521 // Finally, we know we have the right number of parameters, install them. 3522 NewFD->setParams(Params.data(), Params.size()); 3523 3524 // If the declarator is a template-id, translate the parser's template 3525 // argument list into our AST format. 3526 bool HasExplicitTemplateArgs = false; 3527 TemplateArgumentListInfo TemplateArgs; 3528 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3529 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3530 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3531 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3532 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3533 TemplateId->getTemplateArgs(), 3534 TemplateId->NumArgs); 3535 translateTemplateArguments(TemplateArgsPtr, 3536 TemplateArgs); 3537 TemplateArgsPtr.release(); 3538 3539 HasExplicitTemplateArgs = true; 3540 3541 if (FunctionTemplate) { 3542 // FIXME: Diagnose function template with explicit template 3543 // arguments. 3544 HasExplicitTemplateArgs = false; 3545 } else if (!isFunctionTemplateSpecialization && 3546 !D.getDeclSpec().isFriendSpecified()) { 3547 // We have encountered something that the user meant to be a 3548 // specialization (because it has explicitly-specified template 3549 // arguments) but that was not introduced with a "template<>" (or had 3550 // too few of them). 3551 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3552 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3553 << FixItHint::CreateInsertion( 3554 D.getDeclSpec().getSourceRange().getBegin(), 3555 "template<> "); 3556 isFunctionTemplateSpecialization = true; 3557 } else { 3558 // "friend void foo<>(int);" is an implicit specialization decl. 3559 isFunctionTemplateSpecialization = true; 3560 } 3561 } else if (isFriend && isFunctionTemplateSpecialization) { 3562 // This combination is only possible in a recovery case; the user 3563 // wrote something like: 3564 // template <> friend void foo(int); 3565 // which we're recovering from as if the user had written: 3566 // friend void foo<>(int); 3567 // Go ahead and fake up a template id. 3568 HasExplicitTemplateArgs = true; 3569 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3570 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3571 } 3572 3573 // If it's a friend (and only if it's a friend), it's possible 3574 // that either the specialized function type or the specialized 3575 // template is dependent, and therefore matching will fail. In 3576 // this case, don't check the specialization yet. 3577 if (isFunctionTemplateSpecialization && isFriend && 3578 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3579 assert(HasExplicitTemplateArgs && 3580 "friend function specialization without template args"); 3581 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3582 Previous)) 3583 NewFD->setInvalidDecl(); 3584 } else if (isFunctionTemplateSpecialization) { 3585 if (CheckFunctionTemplateSpecialization(NewFD, 3586 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3587 Previous)) 3588 NewFD->setInvalidDecl(); 3589 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3590 if (CheckMemberSpecialization(NewFD, Previous)) 3591 NewFD->setInvalidDecl(); 3592 } 3593 3594 // Perform semantic checking on the function declaration. 3595 bool OverloadableAttrRequired = false; // FIXME: HACK! 3596 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3597 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3598 3599 assert((NewFD->isInvalidDecl() || !Redeclaration || 3600 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3601 "previous declaration set still overloaded"); 3602 3603 NamedDecl *PrincipalDecl = (FunctionTemplate 3604 ? cast<NamedDecl>(FunctionTemplate) 3605 : NewFD); 3606 3607 if (isFriend && Redeclaration) { 3608 AccessSpecifier Access = AS_public; 3609 if (!NewFD->isInvalidDecl()) 3610 Access = NewFD->getPreviousDeclaration()->getAccess(); 3611 3612 NewFD->setAccess(Access); 3613 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3614 3615 PrincipalDecl->setObjectOfFriendDecl(true); 3616 } 3617 3618 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3619 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3620 PrincipalDecl->setNonMemberOperator(); 3621 3622 // If we have a function template, check the template parameter 3623 // list. This will check and merge default template arguments. 3624 if (FunctionTemplate) { 3625 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3626 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3627 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3628 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3629 : TPC_FunctionTemplate); 3630 } 3631 3632 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3633 // Fake up an access specifier if it's supposed to be a class member. 3634 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3635 NewFD->setAccess(AS_public); 3636 3637 // An out-of-line member function declaration must also be a 3638 // definition (C++ [dcl.meaning]p1). 3639 // Note that this is not the case for explicit specializations of 3640 // function templates or member functions of class templates, per 3641 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3642 // for compatibility with old SWIG code which likes to generate them. 3643 if (!IsFunctionDefinition && !isFriend && 3644 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3645 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3646 << D.getCXXScopeSpec().getRange(); 3647 } 3648 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3649 // The user tried to provide an out-of-line definition for a 3650 // function that is a member of a class or namespace, but there 3651 // was no such member function declared (C++ [class.mfct]p2, 3652 // C++ [namespace.memdef]p2). For example: 3653 // 3654 // class X { 3655 // void f() const; 3656 // }; 3657 // 3658 // void X::f() { } // ill-formed 3659 // 3660 // Complain about this problem, and attempt to suggest close 3661 // matches (e.g., those that differ only in cv-qualifiers and 3662 // whether the parameter types are references). 3663 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3664 << Name << DC << D.getCXXScopeSpec().getRange(); 3665 NewFD->setInvalidDecl(); 3666 3667 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3668 ForRedeclaration); 3669 LookupQualifiedName(Prev, DC); 3670 assert(!Prev.isAmbiguous() && 3671 "Cannot have an ambiguity in previous-declaration lookup"); 3672 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3673 Func != FuncEnd; ++Func) { 3674 if (isa<FunctionDecl>(*Func) && 3675 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3676 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3677 } 3678 } 3679 } 3680 3681 // Handle attributes. We need to have merged decls when handling attributes 3682 // (for example to check for conflicts, etc). 3683 // FIXME: This needs to happen before we merge declarations. Then, 3684 // let attribute merging cope with attribute conflicts. 3685 ProcessDeclAttributes(S, NewFD, D); 3686 3687 // attributes declared post-definition are currently ignored 3688 // FIXME: This should happen during attribute merging 3689 if (Redeclaration && Previous.isSingleResult()) { 3690 const FunctionDecl *Def; 3691 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3692 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3693 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3694 Diag(Def->getLocation(), diag::note_previous_definition); 3695 } 3696 } 3697 3698 AddKnownFunctionAttributes(NewFD); 3699 3700 if (OverloadableAttrRequired && !NewFD->hasAttr<OverloadableAttr>()) { 3701 // If a function name is overloadable in C, then every function 3702 // with that name must be marked "overloadable". 3703 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3704 << Redeclaration << NewFD; 3705 if (!Previous.empty()) 3706 Diag(Previous.getRepresentativeDecl()->getLocation(), 3707 diag::note_attribute_overloadable_prev_overload); 3708 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); 3709 } 3710 3711 if (NewFD->hasAttr<OverloadableAttr>() && 3712 !NewFD->getType()->getAs<FunctionProtoType>()) { 3713 Diag(NewFD->getLocation(), 3714 diag::err_attribute_overloadable_no_prototype) 3715 << NewFD; 3716 3717 // Turn this into a variadic function with no parameters. 3718 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3719 QualType R = Context.getFunctionType(FT->getResultType(), 3720 0, 0, true, 0, false, false, 0, 0, 3721 FT->getExtInfo()); 3722 NewFD->setType(R); 3723 } 3724 3725 // If there's a #pragma GCC visibility in scope, and this isn't a class 3726 // member, set the visibility of this function. 3727 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3728 AddPushedVisibilityAttribute(NewFD); 3729 3730 // If this is a locally-scoped extern C function, update the 3731 // map of such names. 3732 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3733 && !NewFD->isInvalidDecl()) 3734 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3735 3736 // Set this FunctionDecl's range up to the right paren. 3737 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3738 3739 if (FunctionTemplate && NewFD->isInvalidDecl()) 3740 FunctionTemplate->setInvalidDecl(); 3741 3742 if (FunctionTemplate) 3743 return FunctionTemplate; 3744 3745 MarkUnusedFileScopedDecl(NewFD); 3746 3747 return NewFD; 3748} 3749 3750/// \brief Perform semantic checking of a new function declaration. 3751/// 3752/// Performs semantic analysis of the new function declaration 3753/// NewFD. This routine performs all semantic checking that does not 3754/// require the actual declarator involved in the declaration, and is 3755/// used both for the declaration of functions as they are parsed 3756/// (called via ActOnDeclarator) and for the declaration of functions 3757/// that have been instantiated via C++ template instantiation (called 3758/// via InstantiateDecl). 3759/// 3760/// \param IsExplicitSpecialiation whether this new function declaration is 3761/// an explicit specialization of the previous declaration. 3762/// 3763/// This sets NewFD->isInvalidDecl() to true if there was an error. 3764void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3765 LookupResult &Previous, 3766 bool IsExplicitSpecialization, 3767 bool &Redeclaration, 3768 bool &OverloadableAttrRequired) { 3769 // If NewFD is already known erroneous, don't do any of this checking. 3770 if (NewFD->isInvalidDecl()) { 3771 // If this is a class member, mark the class invalid immediately. 3772 // This avoids some consistency errors later. 3773 if (isa<CXXMethodDecl>(NewFD)) 3774 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3775 3776 return; 3777 } 3778 3779 if (NewFD->getResultType()->isVariablyModifiedType()) { 3780 // Functions returning a variably modified type violate C99 6.7.5.2p2 3781 // because all functions have linkage. 3782 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3783 return NewFD->setInvalidDecl(); 3784 } 3785 3786 if (NewFD->isMain()) 3787 CheckMain(NewFD); 3788 3789 // Check for a previous declaration of this name. 3790 if (Previous.empty() && NewFD->isExternC()) { 3791 // Since we did not find anything by this name and we're declaring 3792 // an extern "C" function, look for a non-visible extern "C" 3793 // declaration with the same name. 3794 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3795 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3796 if (Pos != LocallyScopedExternalDecls.end()) 3797 Previous.addDecl(Pos->second); 3798 } 3799 3800 // Merge or overload the declaration with an existing declaration of 3801 // the same name, if appropriate. 3802 if (!Previous.empty()) { 3803 // Determine whether NewFD is an overload of PrevDecl or 3804 // a declaration that requires merging. If it's an overload, 3805 // there's no more work to do here; we'll just add the new 3806 // function to the scope. 3807 3808 NamedDecl *OldDecl = 0; 3809 if (!AllowOverloadingOfFunction(Previous, Context)) { 3810 Redeclaration = true; 3811 OldDecl = Previous.getFoundDecl(); 3812 } else { 3813 if (!getLangOptions().CPlusPlus) 3814 OverloadableAttrRequired = true; 3815 3816 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3817 /*NewIsUsingDecl*/ false)) { 3818 case Ovl_Match: 3819 Redeclaration = true; 3820 break; 3821 3822 case Ovl_NonFunction: 3823 Redeclaration = true; 3824 break; 3825 3826 case Ovl_Overload: 3827 Redeclaration = false; 3828 break; 3829 } 3830 } 3831 3832 if (Redeclaration) { 3833 // NewFD and OldDecl represent declarations that need to be 3834 // merged. 3835 if (MergeFunctionDecl(NewFD, OldDecl)) 3836 return NewFD->setInvalidDecl(); 3837 3838 Previous.clear(); 3839 Previous.addDecl(OldDecl); 3840 3841 if (FunctionTemplateDecl *OldTemplateDecl 3842 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3843 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3844 FunctionTemplateDecl *NewTemplateDecl 3845 = NewFD->getDescribedFunctionTemplate(); 3846 assert(NewTemplateDecl && "Template/non-template mismatch"); 3847 if (CXXMethodDecl *Method 3848 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3849 Method->setAccess(OldTemplateDecl->getAccess()); 3850 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3851 } 3852 3853 // If this is an explicit specialization of a member that is a function 3854 // template, mark it as a member specialization. 3855 if (IsExplicitSpecialization && 3856 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3857 NewTemplateDecl->setMemberSpecialization(); 3858 assert(OldTemplateDecl->isMemberSpecialization()); 3859 } 3860 } else { 3861 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3862 NewFD->setAccess(OldDecl->getAccess()); 3863 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3864 } 3865 } 3866 } 3867 3868 // Semantic checking for this function declaration (in isolation). 3869 if (getLangOptions().CPlusPlus) { 3870 // C++-specific checks. 3871 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3872 CheckConstructor(Constructor); 3873 } else if (CXXDestructorDecl *Destructor = 3874 dyn_cast<CXXDestructorDecl>(NewFD)) { 3875 CXXRecordDecl *Record = Destructor->getParent(); 3876 QualType ClassType = Context.getTypeDeclType(Record); 3877 3878 // FIXME: Shouldn't we be able to perform this check even when the class 3879 // type is dependent? Both gcc and edg can handle that. 3880 if (!ClassType->isDependentType()) { 3881 DeclarationName Name 3882 = Context.DeclarationNames.getCXXDestructorName( 3883 Context.getCanonicalType(ClassType)); 3884// NewFD->getDeclName().dump(); 3885// Name.dump(); 3886 if (NewFD->getDeclName() != Name) { 3887 Diag(NewFD->getLocation(), diag::err_destructor_name); 3888 return NewFD->setInvalidDecl(); 3889 } 3890 } 3891 3892 Record->setUserDeclaredDestructor(true); 3893 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3894 // user-defined destructor. 3895 Record->setPOD(false); 3896 3897 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3898 // declared destructor. 3899 // FIXME: C++0x: don't do this for "= default" destructors 3900 Record->setHasTrivialDestructor(false); 3901 } else if (CXXConversionDecl *Conversion 3902 = dyn_cast<CXXConversionDecl>(NewFD)) { 3903 ActOnConversionDeclarator(Conversion); 3904 } 3905 3906 // Find any virtual functions that this function overrides. 3907 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3908 if (!Method->isFunctionTemplateSpecialization() && 3909 !Method->getDescribedFunctionTemplate()) 3910 AddOverriddenMethods(Method->getParent(), Method); 3911 } 3912 3913 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3914 if (NewFD->isOverloadedOperator() && 3915 CheckOverloadedOperatorDeclaration(NewFD)) 3916 return NewFD->setInvalidDecl(); 3917 3918 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3919 if (NewFD->getLiteralIdentifier() && 3920 CheckLiteralOperatorDeclaration(NewFD)) 3921 return NewFD->setInvalidDecl(); 3922 3923 // In C++, check default arguments now that we have merged decls. Unless 3924 // the lexical context is the class, because in this case this is done 3925 // during delayed parsing anyway. 3926 if (!CurContext->isRecord()) 3927 CheckCXXDefaultArguments(NewFD); 3928 } 3929} 3930 3931void Sema::CheckMain(FunctionDecl* FD) { 3932 // C++ [basic.start.main]p3: A program that declares main to be inline 3933 // or static is ill-formed. 3934 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3935 // shall not appear in a declaration of main. 3936 // static main is not an error under C99, but we should warn about it. 3937 bool isInline = FD->isInlineSpecified(); 3938 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3939 if (isInline || isStatic) { 3940 unsigned diagID = diag::warn_unusual_main_decl; 3941 if (isInline || getLangOptions().CPlusPlus) 3942 diagID = diag::err_unusual_main_decl; 3943 3944 int which = isStatic + (isInline << 1) - 1; 3945 Diag(FD->getLocation(), diagID) << which; 3946 } 3947 3948 QualType T = FD->getType(); 3949 assert(T->isFunctionType() && "function decl is not of function type"); 3950 const FunctionType* FT = T->getAs<FunctionType>(); 3951 3952 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3953 // TODO: add a replacement fixit to turn the return type into 'int'. 3954 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3955 FD->setInvalidDecl(true); 3956 } 3957 3958 // Treat protoless main() as nullary. 3959 if (isa<FunctionNoProtoType>(FT)) return; 3960 3961 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3962 unsigned nparams = FTP->getNumArgs(); 3963 assert(FD->getNumParams() == nparams); 3964 3965 bool HasExtraParameters = (nparams > 3); 3966 3967 // Darwin passes an undocumented fourth argument of type char**. If 3968 // other platforms start sprouting these, the logic below will start 3969 // getting shifty. 3970 if (nparams == 4 && 3971 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3972 HasExtraParameters = false; 3973 3974 if (HasExtraParameters) { 3975 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3976 FD->setInvalidDecl(true); 3977 nparams = 3; 3978 } 3979 3980 // FIXME: a lot of the following diagnostics would be improved 3981 // if we had some location information about types. 3982 3983 QualType CharPP = 3984 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3985 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3986 3987 for (unsigned i = 0; i < nparams; ++i) { 3988 QualType AT = FTP->getArgType(i); 3989 3990 bool mismatch = true; 3991 3992 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3993 mismatch = false; 3994 else if (Expected[i] == CharPP) { 3995 // As an extension, the following forms are okay: 3996 // char const ** 3997 // char const * const * 3998 // char * const * 3999 4000 QualifierCollector qs; 4001 const PointerType* PT; 4002 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4003 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4004 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4005 qs.removeConst(); 4006 mismatch = !qs.empty(); 4007 } 4008 } 4009 4010 if (mismatch) { 4011 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4012 // TODO: suggest replacing given type with expected type 4013 FD->setInvalidDecl(true); 4014 } 4015 } 4016 4017 if (nparams == 1 && !FD->isInvalidDecl()) { 4018 Diag(FD->getLocation(), diag::warn_main_one_arg); 4019 } 4020} 4021 4022bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4023 // FIXME: Need strict checking. In C89, we need to check for 4024 // any assignment, increment, decrement, function-calls, or 4025 // commas outside of a sizeof. In C99, it's the same list, 4026 // except that the aforementioned are allowed in unevaluated 4027 // expressions. Everything else falls under the 4028 // "may accept other forms of constant expressions" exception. 4029 // (We never end up here for C++, so the constant expression 4030 // rules there don't matter.) 4031 if (Init->isConstantInitializer(Context, false)) 4032 return false; 4033 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4034 << Init->getSourceRange(); 4035 return true; 4036} 4037 4038void Sema::AddInitializerToDecl(Decl *dcl, Expr *init) { 4039 AddInitializerToDecl(dcl, init, /*DirectInit=*/false); 4040} 4041 4042/// AddInitializerToDecl - Adds the initializer Init to the 4043/// declaration dcl. If DirectInit is true, this is C++ direct 4044/// initialization rather than copy initialization. 4045void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) { 4046 // If there is no declaration, there was an error parsing it. Just ignore 4047 // the initializer. 4048 if (RealDecl == 0) 4049 return; 4050 4051 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4052 // With declarators parsed the way they are, the parser cannot 4053 // distinguish between a normal initializer and a pure-specifier. 4054 // Thus this grotesque test. 4055 IntegerLiteral *IL; 4056 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4057 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4058 CheckPureMethod(Method, Init->getSourceRange()); 4059 else { 4060 Diag(Method->getLocation(), diag::err_member_function_initialization) 4061 << Method->getDeclName() << Init->getSourceRange(); 4062 Method->setInvalidDecl(); 4063 } 4064 return; 4065 } 4066 4067 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4068 if (!VDecl) { 4069 if (getLangOptions().CPlusPlus && 4070 RealDecl->getLexicalDeclContext()->isRecord() && 4071 isa<NamedDecl>(RealDecl)) 4072 Diag(RealDecl->getLocation(), diag::err_member_initialization) 4073 << cast<NamedDecl>(RealDecl)->getDeclName(); 4074 else 4075 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4076 RealDecl->setInvalidDecl(); 4077 return; 4078 } 4079 4080 // A definition must end up with a complete type, which means it must be 4081 // complete with the restriction that an array type might be completed by the 4082 // initializer; note that later code assumes this restriction. 4083 QualType BaseDeclType = VDecl->getType(); 4084 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4085 BaseDeclType = Array->getElementType(); 4086 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4087 diag::err_typecheck_decl_incomplete_type)) { 4088 RealDecl->setInvalidDecl(); 4089 return; 4090 } 4091 4092 // The variable can not have an abstract class type. 4093 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4094 diag::err_abstract_type_in_decl, 4095 AbstractVariableType)) 4096 VDecl->setInvalidDecl(); 4097 4098 const VarDecl *Def; 4099 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4100 Diag(VDecl->getLocation(), diag::err_redefinition) 4101 << VDecl->getDeclName(); 4102 Diag(Def->getLocation(), diag::note_previous_definition); 4103 VDecl->setInvalidDecl(); 4104 return; 4105 } 4106 4107 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4108 setFunctionHasBranchProtectedScope(); 4109 4110 // Capture the variable that is being initialized and the style of 4111 // initialization. 4112 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4113 4114 // FIXME: Poor source location information. 4115 InitializationKind Kind 4116 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4117 Init->getLocStart(), 4118 Init->getLocEnd()) 4119 : InitializationKind::CreateCopy(VDecl->getLocation(), 4120 Init->getLocStart()); 4121 4122 // Get the decls type and save a reference for later, since 4123 // CheckInitializerTypes may change it. 4124 QualType DclT = VDecl->getType(), SavT = DclT; 4125 if (VDecl->isBlockVarDecl()) { 4126 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4127 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4128 VDecl->setInvalidDecl(); 4129 } else if (!VDecl->isInvalidDecl()) { 4130 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4131 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4132 MultiExprArg(*this, &Init, 1), 4133 &DclT); 4134 if (Result.isInvalid()) { 4135 VDecl->setInvalidDecl(); 4136 return; 4137 } 4138 4139 Init = Result.takeAs<Expr>(); 4140 4141 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4142 // Don't check invalid declarations to avoid emitting useless diagnostics. 4143 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4144 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 4145 CheckForConstantInitializer(Init, DclT); 4146 } 4147 } 4148 } else if (VDecl->isStaticDataMember() && 4149 VDecl->getLexicalDeclContext()->isRecord()) { 4150 // This is an in-class initialization for a static data member, e.g., 4151 // 4152 // struct S { 4153 // static const int value = 17; 4154 // }; 4155 4156 // Attach the initializer 4157 VDecl->setInit(Init); 4158 4159 // C++ [class.mem]p4: 4160 // A member-declarator can contain a constant-initializer only 4161 // if it declares a static member (9.4) of const integral or 4162 // const enumeration type, see 9.4.2. 4163 QualType T = VDecl->getType(); 4164 if (!T->isDependentType() && 4165 (!Context.getCanonicalType(T).isConstQualified() || 4166 !T->isIntegralOrEnumerationType())) { 4167 Diag(VDecl->getLocation(), diag::err_member_initialization) 4168 << VDecl->getDeclName() << Init->getSourceRange(); 4169 VDecl->setInvalidDecl(); 4170 } else { 4171 // C++ [class.static.data]p4: 4172 // If a static data member is of const integral or const 4173 // enumeration type, its declaration in the class definition 4174 // can specify a constant-initializer which shall be an 4175 // integral constant expression (5.19). 4176 if (!Init->isTypeDependent() && 4177 !Init->getType()->isIntegralOrEnumerationType()) { 4178 // We have a non-dependent, non-integral or enumeration type. 4179 Diag(Init->getSourceRange().getBegin(), 4180 diag::err_in_class_initializer_non_integral_type) 4181 << Init->getType() << Init->getSourceRange(); 4182 VDecl->setInvalidDecl(); 4183 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4184 // Check whether the expression is a constant expression. 4185 llvm::APSInt Value; 4186 SourceLocation Loc; 4187 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4188 Diag(Loc, diag::err_in_class_initializer_non_constant) 4189 << Init->getSourceRange(); 4190 VDecl->setInvalidDecl(); 4191 } else if (!VDecl->getType()->isDependentType()) 4192 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4193 } 4194 } 4195 } else if (VDecl->isFileVarDecl()) { 4196 if (VDecl->getStorageClass() == VarDecl::Extern && 4197 (!getLangOptions().CPlusPlus || 4198 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4199 Diag(VDecl->getLocation(), diag::warn_extern_init); 4200 if (!VDecl->isInvalidDecl()) { 4201 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4202 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4203 MultiExprArg(*this, &Init, 1), 4204 &DclT); 4205 if (Result.isInvalid()) { 4206 VDecl->setInvalidDecl(); 4207 return; 4208 } 4209 4210 Init = Result.takeAs<Expr>(); 4211 } 4212 4213 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4214 // Don't check invalid declarations to avoid emitting useless diagnostics. 4215 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4216 // C99 6.7.8p4. All file scoped initializers need to be constant. 4217 CheckForConstantInitializer(Init, DclT); 4218 } 4219 } 4220 // If the type changed, it means we had an incomplete type that was 4221 // completed by the initializer. For example: 4222 // int ary[] = { 1, 3, 5 }; 4223 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4224 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4225 VDecl->setType(DclT); 4226 Init->setType(DclT); 4227 } 4228 4229 Init = MaybeCreateCXXExprWithTemporaries(Init); 4230 // Attach the initializer to the decl. 4231 VDecl->setInit(Init); 4232 4233 if (getLangOptions().CPlusPlus) { 4234 if (!VDecl->isInvalidDecl() && 4235 !VDecl->getDeclContext()->isDependentContext() && 4236 VDecl->hasGlobalStorage() && 4237 !Init->isConstantInitializer(Context, 4238 VDecl->getType()->isReferenceType())) 4239 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4240 << Init->getSourceRange(); 4241 4242 // Make sure we mark the destructor as used if necessary. 4243 QualType InitType = VDecl->getType(); 4244 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4245 InitType = Context.getBaseElementType(Array); 4246 if (const RecordType *Record = InitType->getAs<RecordType>()) 4247 FinalizeVarWithDestructor(VDecl, Record); 4248 } 4249 4250 return; 4251} 4252 4253/// ActOnInitializerError - Given that there was an error parsing an 4254/// initializer for the given declaration, try to return to some form 4255/// of sanity. 4256void Sema::ActOnInitializerError(Decl *D) { 4257 // Our main concern here is re-establishing invariants like "a 4258 // variable's type is either dependent or complete". 4259 if (!D || D->isInvalidDecl()) return; 4260 4261 VarDecl *VD = dyn_cast<VarDecl>(D); 4262 if (!VD) return; 4263 4264 QualType Ty = VD->getType(); 4265 if (Ty->isDependentType()) return; 4266 4267 // Require a complete type. 4268 if (RequireCompleteType(VD->getLocation(), 4269 Context.getBaseElementType(Ty), 4270 diag::err_typecheck_decl_incomplete_type)) { 4271 VD->setInvalidDecl(); 4272 return; 4273 } 4274 4275 // Require an abstract type. 4276 if (RequireNonAbstractType(VD->getLocation(), Ty, 4277 diag::err_abstract_type_in_decl, 4278 AbstractVariableType)) { 4279 VD->setInvalidDecl(); 4280 return; 4281 } 4282 4283 // Don't bother complaining about constructors or destructors, 4284 // though. 4285} 4286 4287void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4288 bool TypeContainsUndeducedAuto) { 4289 // If there is no declaration, there was an error parsing it. Just ignore it. 4290 if (RealDecl == 0) 4291 return; 4292 4293 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4294 QualType Type = Var->getType(); 4295 4296 // C++0x [dcl.spec.auto]p3 4297 if (TypeContainsUndeducedAuto) { 4298 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4299 << Var->getDeclName() << Type; 4300 Var->setInvalidDecl(); 4301 return; 4302 } 4303 4304 switch (Var->isThisDeclarationADefinition()) { 4305 case VarDecl::Definition: 4306 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4307 break; 4308 4309 // We have an out-of-line definition of a static data member 4310 // that has an in-class initializer, so we type-check this like 4311 // a declaration. 4312 // 4313 // Fall through 4314 4315 case VarDecl::DeclarationOnly: 4316 // It's only a declaration. 4317 4318 // Block scope. C99 6.7p7: If an identifier for an object is 4319 // declared with no linkage (C99 6.2.2p6), the type for the 4320 // object shall be complete. 4321 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4322 !Var->getLinkage() && !Var->isInvalidDecl() && 4323 RequireCompleteType(Var->getLocation(), Type, 4324 diag::err_typecheck_decl_incomplete_type)) 4325 Var->setInvalidDecl(); 4326 4327 // Make sure that the type is not abstract. 4328 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4329 RequireNonAbstractType(Var->getLocation(), Type, 4330 diag::err_abstract_type_in_decl, 4331 AbstractVariableType)) 4332 Var->setInvalidDecl(); 4333 return; 4334 4335 case VarDecl::TentativeDefinition: 4336 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4337 // object that has file scope without an initializer, and without a 4338 // storage-class specifier or with the storage-class specifier "static", 4339 // constitutes a tentative definition. Note: A tentative definition with 4340 // external linkage is valid (C99 6.2.2p5). 4341 if (!Var->isInvalidDecl()) { 4342 if (const IncompleteArrayType *ArrayT 4343 = Context.getAsIncompleteArrayType(Type)) { 4344 if (RequireCompleteType(Var->getLocation(), 4345 ArrayT->getElementType(), 4346 diag::err_illegal_decl_array_incomplete_type)) 4347 Var->setInvalidDecl(); 4348 } else if (Var->getStorageClass() == VarDecl::Static) { 4349 // C99 6.9.2p3: If the declaration of an identifier for an object is 4350 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4351 // declared type shall not be an incomplete type. 4352 // NOTE: code such as the following 4353 // static struct s; 4354 // struct s { int a; }; 4355 // is accepted by gcc. Hence here we issue a warning instead of 4356 // an error and we do not invalidate the static declaration. 4357 // NOTE: to avoid multiple warnings, only check the first declaration. 4358 if (Var->getPreviousDeclaration() == 0) 4359 RequireCompleteType(Var->getLocation(), Type, 4360 diag::ext_typecheck_decl_incomplete_type); 4361 } 4362 } 4363 4364 // Record the tentative definition; we're done. 4365 if (!Var->isInvalidDecl()) 4366 TentativeDefinitions.push_back(Var); 4367 return; 4368 } 4369 4370 // Provide a specific diagnostic for uninitialized variable 4371 // definitions with incomplete array type. 4372 if (Type->isIncompleteArrayType()) { 4373 Diag(Var->getLocation(), 4374 diag::err_typecheck_incomplete_array_needs_initializer); 4375 Var->setInvalidDecl(); 4376 return; 4377 } 4378 4379 // Provide a specific diagnostic for uninitialized variable 4380 // definitions with reference type. 4381 if (Type->isReferenceType()) { 4382 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4383 << Var->getDeclName() 4384 << SourceRange(Var->getLocation(), Var->getLocation()); 4385 Var->setInvalidDecl(); 4386 return; 4387 } 4388 4389 // Do not attempt to type-check the default initializer for a 4390 // variable with dependent type. 4391 if (Type->isDependentType()) 4392 return; 4393 4394 if (Var->isInvalidDecl()) 4395 return; 4396 4397 if (RequireCompleteType(Var->getLocation(), 4398 Context.getBaseElementType(Type), 4399 diag::err_typecheck_decl_incomplete_type)) { 4400 Var->setInvalidDecl(); 4401 return; 4402 } 4403 4404 // The variable can not have an abstract class type. 4405 if (RequireNonAbstractType(Var->getLocation(), Type, 4406 diag::err_abstract_type_in_decl, 4407 AbstractVariableType)) { 4408 Var->setInvalidDecl(); 4409 return; 4410 } 4411 4412 const RecordType *Record 4413 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4414 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4415 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4416 // C++03 [dcl.init]p9: 4417 // If no initializer is specified for an object, and the 4418 // object is of (possibly cv-qualified) non-POD class type (or 4419 // array thereof), the object shall be default-initialized; if 4420 // the object is of const-qualified type, the underlying class 4421 // type shall have a user-declared default 4422 // constructor. Otherwise, if no initializer is specified for 4423 // a non- static object, the object and its subobjects, if 4424 // any, have an indeterminate initial value); if the object 4425 // or any of its subobjects are of const-qualified type, the 4426 // program is ill-formed. 4427 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4428 } else { 4429 // Check for jumps past the implicit initializer. C++0x 4430 // clarifies that this applies to a "variable with automatic 4431 // storage duration", not a "local variable". 4432 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4433 setFunctionHasBranchProtectedScope(); 4434 4435 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4436 InitializationKind Kind 4437 = InitializationKind::CreateDefault(Var->getLocation()); 4438 4439 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4440 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4441 MultiExprArg(*this, 0, 0)); 4442 if (Init.isInvalid()) 4443 Var->setInvalidDecl(); 4444 else if (Init.get()) { 4445 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4446 4447 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4448 Var->hasGlobalStorage() && 4449 !Var->getDeclContext()->isDependentContext() && 4450 !Var->getInit()->isConstantInitializer(Context, false)) 4451 Diag(Var->getLocation(), diag::warn_global_constructor); 4452 } 4453 } 4454 4455 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4456 FinalizeVarWithDestructor(Var, Record); 4457 } 4458} 4459 4460Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4461 Decl **Group, 4462 unsigned NumDecls) { 4463 llvm::SmallVector<Decl*, 8> Decls; 4464 4465 if (DS.isTypeSpecOwned()) 4466 Decls.push_back((Decl*)DS.getTypeRep()); 4467 4468 for (unsigned i = 0; i != NumDecls; ++i) 4469 if (Decl *D = Group[i]) 4470 Decls.push_back(D); 4471 4472 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4473 Decls.data(), Decls.size())); 4474} 4475 4476 4477/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4478/// to introduce parameters into function prototype scope. 4479Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4480 const DeclSpec &DS = D.getDeclSpec(); 4481 4482 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4483 VarDecl::StorageClass StorageClass = VarDecl::None; 4484 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4485 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4486 StorageClass = VarDecl::Register; 4487 StorageClassAsWritten = VarDecl::Register; 4488 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4489 Diag(DS.getStorageClassSpecLoc(), 4490 diag::err_invalid_storage_class_in_func_decl); 4491 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4492 } 4493 4494 if (D.getDeclSpec().isThreadSpecified()) 4495 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4496 4497 DiagnoseFunctionSpecifiers(D); 4498 4499 // Check that there are no default arguments inside the type of this 4500 // parameter (C++ only). 4501 if (getLangOptions().CPlusPlus) 4502 CheckExtraCXXDefaultArguments(D); 4503 4504 TagDecl *OwnedDecl = 0; 4505 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4506 QualType parmDeclType = TInfo->getType(); 4507 4508 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4509 // C++ [dcl.fct]p6: 4510 // Types shall not be defined in return or parameter types. 4511 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4512 << Context.getTypeDeclType(OwnedDecl); 4513 } 4514 4515 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4516 IdentifierInfo *II = D.getIdentifier(); 4517 if (II) { 4518 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4519 ForRedeclaration); 4520 LookupName(R, S); 4521 if (R.isSingleResult()) { 4522 NamedDecl *PrevDecl = R.getFoundDecl(); 4523 if (PrevDecl->isTemplateParameter()) { 4524 // Maybe we will complain about the shadowed template parameter. 4525 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4526 // Just pretend that we didn't see the previous declaration. 4527 PrevDecl = 0; 4528 } else if (S->isDeclScope(PrevDecl)) { 4529 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4530 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4531 4532 // Recover by removing the name 4533 II = 0; 4534 D.SetIdentifier(0, D.getIdentifierLoc()); 4535 D.setInvalidType(true); 4536 } 4537 } 4538 } 4539 4540 // Temporarily put parameter variables in the translation unit, not 4541 // the enclosing context. This prevents them from accidentally 4542 // looking like class members in C++. 4543 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4544 TInfo, parmDeclType, II, 4545 D.getIdentifierLoc(), 4546 StorageClass, StorageClassAsWritten); 4547 4548 if (D.isInvalidType()) 4549 New->setInvalidDecl(); 4550 4551 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4552 if (D.getCXXScopeSpec().isSet()) { 4553 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4554 << D.getCXXScopeSpec().getRange(); 4555 New->setInvalidDecl(); 4556 } 4557 4558 // Add the parameter declaration into this scope. 4559 S->AddDecl(New); 4560 if (II) 4561 IdResolver.AddDecl(New); 4562 4563 ProcessDeclAttributes(S, New, D); 4564 4565 if (New->hasAttr<BlocksAttr>()) { 4566 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4567 } 4568 return New; 4569} 4570 4571/// \brief Synthesizes a variable for a parameter arising from a 4572/// typedef. 4573ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4574 SourceLocation Loc, 4575 QualType T) { 4576 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4577 T, Context.getTrivialTypeSourceInfo(T, Loc), 4578 VarDecl::None, VarDecl::None, 0); 4579 Param->setImplicit(); 4580 return Param; 4581} 4582 4583ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4584 TypeSourceInfo *TSInfo, QualType T, 4585 IdentifierInfo *Name, 4586 SourceLocation NameLoc, 4587 VarDecl::StorageClass StorageClass, 4588 VarDecl::StorageClass StorageClassAsWritten) { 4589 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4590 adjustParameterType(T), TSInfo, 4591 StorageClass, StorageClassAsWritten, 4592 0); 4593 4594 // Parameters can not be abstract class types. 4595 // For record types, this is done by the AbstractClassUsageDiagnoser once 4596 // the class has been completely parsed. 4597 if (!CurContext->isRecord() && 4598 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4599 AbstractParamType)) 4600 New->setInvalidDecl(); 4601 4602 // Parameter declarators cannot be interface types. All ObjC objects are 4603 // passed by reference. 4604 if (T->isObjCObjectType()) { 4605 Diag(NameLoc, 4606 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4607 New->setInvalidDecl(); 4608 } 4609 4610 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4611 // duration shall not be qualified by an address-space qualifier." 4612 // Since all parameters have automatic store duration, they can not have 4613 // an address space. 4614 if (T.getAddressSpace() != 0) { 4615 Diag(NameLoc, diag::err_arg_with_address_space); 4616 New->setInvalidDecl(); 4617 } 4618 4619 return New; 4620} 4621 4622void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4623 SourceLocation LocAfterDecls) { 4624 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4625 "Not a function declarator!"); 4626 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4627 4628 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4629 // for a K&R function. 4630 if (!FTI.hasPrototype) { 4631 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4632 --i; 4633 if (FTI.ArgInfo[i].Param == 0) { 4634 llvm::SmallString<256> Code; 4635 llvm::raw_svector_ostream(Code) << " int " 4636 << FTI.ArgInfo[i].Ident->getName() 4637 << ";\n"; 4638 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4639 << FTI.ArgInfo[i].Ident 4640 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4641 4642 // Implicitly declare the argument as type 'int' for lack of a better 4643 // type. 4644 DeclSpec DS; 4645 const char* PrevSpec; // unused 4646 unsigned DiagID; // unused 4647 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4648 PrevSpec, DiagID); 4649 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4650 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4651 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4652 } 4653 } 4654 } 4655} 4656 4657Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4658 Declarator &D) { 4659 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4660 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4661 "Not a function declarator!"); 4662 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4663 4664 if (FTI.hasPrototype) { 4665 // FIXME: Diagnose arguments without names in C. 4666 } 4667 4668 Scope *ParentScope = FnBodyScope->getParent(); 4669 4670 Decl *DP = HandleDeclarator(ParentScope, D, 4671 MultiTemplateParamsArg(*this), 4672 /*IsFunctionDefinition=*/true); 4673 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4674} 4675 4676static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4677 // Don't warn about invalid declarations. 4678 if (FD->isInvalidDecl()) 4679 return false; 4680 4681 // Or declarations that aren't global. 4682 if (!FD->isGlobal()) 4683 return false; 4684 4685 // Don't warn about C++ member functions. 4686 if (isa<CXXMethodDecl>(FD)) 4687 return false; 4688 4689 // Don't warn about 'main'. 4690 if (FD->isMain()) 4691 return false; 4692 4693 // Don't warn about inline functions. 4694 if (FD->isInlineSpecified()) 4695 return false; 4696 4697 // Don't warn about function templates. 4698 if (FD->getDescribedFunctionTemplate()) 4699 return false; 4700 4701 // Don't warn about function template specializations. 4702 if (FD->isFunctionTemplateSpecialization()) 4703 return false; 4704 4705 bool MissingPrototype = true; 4706 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4707 Prev; Prev = Prev->getPreviousDeclaration()) { 4708 // Ignore any declarations that occur in function or method 4709 // scope, because they aren't visible from the header. 4710 if (Prev->getDeclContext()->isFunctionOrMethod()) 4711 continue; 4712 4713 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4714 break; 4715 } 4716 4717 return MissingPrototype; 4718} 4719 4720Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 4721 // Clear the last template instantiation error context. 4722 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4723 4724 if (!D) 4725 return D; 4726 FunctionDecl *FD = 0; 4727 4728 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 4729 FD = FunTmpl->getTemplatedDecl(); 4730 else 4731 FD = cast<FunctionDecl>(D); 4732 4733 // Enter a new function scope 4734 PushFunctionScope(); 4735 4736 // See if this is a redefinition. 4737 // But don't complain if we're in GNU89 mode and the previous definition 4738 // was an extern inline function. 4739 const FunctionDecl *Definition; 4740 if (FD->hasBody(Definition) && 4741 !canRedefineFunction(Definition, getLangOptions())) { 4742 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4743 Diag(Definition->getLocation(), diag::note_previous_definition); 4744 } 4745 4746 // Builtin functions cannot be defined. 4747 if (unsigned BuiltinID = FD->getBuiltinID()) { 4748 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4749 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4750 FD->setInvalidDecl(); 4751 } 4752 } 4753 4754 // The return type of a function definition must be complete 4755 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4756 QualType ResultType = FD->getResultType(); 4757 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4758 !FD->isInvalidDecl() && 4759 RequireCompleteType(FD->getLocation(), ResultType, 4760 diag::err_func_def_incomplete_result)) 4761 FD->setInvalidDecl(); 4762 4763 // GNU warning -Wmissing-prototypes: 4764 // Warn if a global function is defined without a previous 4765 // prototype declaration. This warning is issued even if the 4766 // definition itself provides a prototype. The aim is to detect 4767 // global functions that fail to be declared in header files. 4768 if (ShouldWarnAboutMissingPrototype(FD)) 4769 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4770 4771 if (FnBodyScope) 4772 PushDeclContext(FnBodyScope, FD); 4773 4774 // Check the validity of our function parameters 4775 CheckParmsForFunctionDef(FD); 4776 4777 bool ShouldCheckShadow = 4778 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4779 4780 // Introduce our parameters into the function scope 4781 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4782 ParmVarDecl *Param = FD->getParamDecl(p); 4783 Param->setOwningFunction(FD); 4784 4785 // If this has an identifier, add it to the scope stack. 4786 if (Param->getIdentifier() && FnBodyScope) { 4787 if (ShouldCheckShadow) 4788 CheckShadow(FnBodyScope, Param); 4789 4790 PushOnScopeChains(Param, FnBodyScope); 4791 } 4792 } 4793 4794 // Checking attributes of current function definition 4795 // dllimport attribute. 4796 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 4797 if (DA && (!FD->getAttr<DLLExportAttr>())) { 4798 // dllimport attribute cannot be directly applied to definition. 4799 if (!DA->isInherited()) { 4800 Diag(FD->getLocation(), 4801 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4802 << "dllimport"; 4803 FD->setInvalidDecl(); 4804 return FD; 4805 } 4806 4807 // Visual C++ appears to not think this is an issue, so only issue 4808 // a warning when Microsoft extensions are disabled. 4809 if (!LangOpts.Microsoft) { 4810 // If a symbol previously declared dllimport is later defined, the 4811 // attribute is ignored in subsequent references, and a warning is 4812 // emitted. 4813 Diag(FD->getLocation(), 4814 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4815 << FD->getName() << "dllimport"; 4816 } 4817 } 4818 return FD; 4819} 4820 4821/// \brief Given the set of return statements within a function body, 4822/// compute the variables that are subject to the named return value 4823/// optimization. 4824/// 4825/// Each of the variables that is subject to the named return value 4826/// optimization will be marked as NRVO variables in the AST, and any 4827/// return statement that has a marked NRVO variable as its NRVO candidate can 4828/// use the named return value optimization. 4829/// 4830/// This function applies a very simplistic algorithm for NRVO: if every return 4831/// statement in the function has the same NRVO candidate, that candidate is 4832/// the NRVO variable. 4833/// 4834/// FIXME: Employ a smarter algorithm that accounts for multiple return 4835/// statements and the lifetimes of the NRVO candidates. We should be able to 4836/// find a maximal set of NRVO variables. 4837static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4838 const VarDecl *NRVOCandidate = 0; 4839 for (unsigned I = 0; I != NumReturns; ++I) { 4840 if (!Returns[I]->getNRVOCandidate()) 4841 return; 4842 4843 if (!NRVOCandidate) 4844 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4845 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4846 return; 4847 } 4848 4849 if (NRVOCandidate) 4850 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4851} 4852 4853Decl *Sema::ActOnFinishFunctionBody(Decl *D, StmtArg BodyArg) { 4854 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4855} 4856 4857Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 4858 bool IsInstantiation) { 4859 FunctionDecl *FD = 0; 4860 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4861 if (FunTmpl) 4862 FD = FunTmpl->getTemplatedDecl(); 4863 else 4864 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4865 4866 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4867 4868 if (FD) { 4869 FD->setBody(Body); 4870 if (FD->isMain()) { 4871 // C and C++ allow for main to automagically return 0. 4872 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4873 FD->setHasImplicitReturnZero(true); 4874 WP.disableCheckFallThrough(); 4875 } 4876 4877 if (!FD->isInvalidDecl()) { 4878 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4879 4880 // If this is a constructor, we need a vtable. 4881 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4882 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4883 4884 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4885 FunctionScopes.back()->Returns.size()); 4886 } 4887 4888 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4889 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4890 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4891 MD->setBody(Body); 4892 MD->setEndLoc(Body->getLocEnd()); 4893 if (!MD->isInvalidDecl()) 4894 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4895 } else { 4896 return 0; 4897 } 4898 4899 // Verify and clean out per-function state. 4900 4901 // Check goto/label use. 4902 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4903 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4904 LabelStmt *L = I->second; 4905 4906 // Verify that we have no forward references left. If so, there was a goto 4907 // or address of a label taken, but no definition of it. Label fwd 4908 // definitions are indicated with a null substmt. 4909 if (L->getSubStmt() != 0) 4910 continue; 4911 4912 // Emit error. 4913 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4914 4915 // At this point, we have gotos that use the bogus label. Stitch it into 4916 // the function body so that they aren't leaked and that the AST is well 4917 // formed. 4918 if (Body == 0) { 4919 // The whole function wasn't parsed correctly. 4920 continue; 4921 } 4922 4923 // Otherwise, the body is valid: we want to stitch the label decl into the 4924 // function somewhere so that it is properly owned and so that the goto 4925 // has a valid target. Do this by creating a new compound stmt with the 4926 // label in it. 4927 4928 // Give the label a sub-statement. 4929 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4930 4931 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4932 cast<CXXTryStmt>(Body)->getTryBlock() : 4933 cast<CompoundStmt>(Body); 4934 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4935 Compound->body_end()); 4936 Elements.push_back(L); 4937 Compound->setStmts(Context, Elements.data(), Elements.size()); 4938 } 4939 4940 if (Body) { 4941 // C++ constructors that have function-try-blocks can't have return 4942 // statements in the handlers of that block. (C++ [except.handle]p14) 4943 // Verify this. 4944 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4945 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4946 4947 // Verify that that gotos and switch cases don't jump into scopes illegally. 4948 // Verify that that gotos and switch cases don't jump into scopes illegally. 4949 if (FunctionNeedsScopeChecking() && 4950 !dcl->isInvalidDecl() && 4951 !hasAnyErrorsInThisFunction()) 4952 DiagnoseInvalidJumps(Body); 4953 4954 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 4955 if (!Destructor->getParent()->isDependentType()) 4956 CheckDestructor(Destructor); 4957 4958 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4959 Destructor->getParent()); 4960 } 4961 4962 // If any errors have occurred, clear out any temporaries that may have 4963 // been leftover. This ensures that these temporaries won't be picked up for 4964 // deletion in some later function. 4965 if (PP.getDiagnostics().hasErrorOccurred()) 4966 ExprTemporaries.clear(); 4967 else if (!isa<FunctionTemplateDecl>(dcl)) { 4968 // Since the body is valid, issue any analysis-based warnings that are 4969 // enabled. 4970 QualType ResultType; 4971 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4972 ResultType = FD->getResultType(); 4973 } 4974 else { 4975 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4976 ResultType = MD->getResultType(); 4977 } 4978 AnalysisWarnings.IssueWarnings(WP, dcl); 4979 } 4980 4981 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4982 } 4983 4984 if (!IsInstantiation) 4985 PopDeclContext(); 4986 4987 PopFunctionOrBlockScope(); 4988 4989 // If any errors have occurred, clear out any temporaries that may have 4990 // been leftover. This ensures that these temporaries won't be picked up for 4991 // deletion in some later function. 4992 if (getDiagnostics().hasErrorOccurred()) 4993 ExprTemporaries.clear(); 4994 4995 return dcl; 4996} 4997 4998/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4999/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5000NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5001 IdentifierInfo &II, Scope *S) { 5002 // Before we produce a declaration for an implicitly defined 5003 // function, see whether there was a locally-scoped declaration of 5004 // this name as a function or variable. If so, use that 5005 // (non-visible) declaration, and complain about it. 5006 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5007 = LocallyScopedExternalDecls.find(&II); 5008 if (Pos != LocallyScopedExternalDecls.end()) { 5009 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5010 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5011 return Pos->second; 5012 } 5013 5014 // Extension in C99. Legal in C90, but warn about it. 5015 if (II.getName().startswith("__builtin_")) 5016 Diag(Loc, diag::warn_builtin_unknown) << &II; 5017 else if (getLangOptions().C99) 5018 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5019 else 5020 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5021 5022 // Set a Declarator for the implicit definition: int foo(); 5023 const char *Dummy; 5024 DeclSpec DS; 5025 unsigned DiagID; 5026 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5027 Error = Error; // Silence warning. 5028 assert(!Error && "Error setting up implicit decl!"); 5029 Declarator D(DS, Declarator::BlockContext); 5030 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5031 0, 0, false, SourceLocation(), 5032 false, 0,0,0, Loc, Loc, D), 5033 SourceLocation()); 5034 D.SetIdentifier(&II, Loc); 5035 5036 // Insert this function into translation-unit scope. 5037 5038 DeclContext *PrevDC = CurContext; 5039 CurContext = Context.getTranslationUnitDecl(); 5040 5041 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5042 FD->setImplicit(); 5043 5044 CurContext = PrevDC; 5045 5046 AddKnownFunctionAttributes(FD); 5047 5048 return FD; 5049} 5050 5051/// \brief Adds any function attributes that we know a priori based on 5052/// the declaration of this function. 5053/// 5054/// These attributes can apply both to implicitly-declared builtins 5055/// (like __builtin___printf_chk) or to library-declared functions 5056/// like NSLog or printf. 5057void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5058 if (FD->isInvalidDecl()) 5059 return; 5060 5061 // If this is a built-in function, map its builtin attributes to 5062 // actual attributes. 5063 if (unsigned BuiltinID = FD->getBuiltinID()) { 5064 // Handle printf-formatting attributes. 5065 unsigned FormatIdx; 5066 bool HasVAListArg; 5067 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5068 if (!FD->getAttr<FormatAttr>()) 5069 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5070 "printf", FormatIdx+1, 5071 HasVAListArg ? 0 : FormatIdx+2)); 5072 } 5073 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5074 HasVAListArg)) { 5075 if (!FD->getAttr<FormatAttr>()) 5076 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5077 "scanf", FormatIdx+1, 5078 HasVAListArg ? 0 : FormatIdx+2)); 5079 } 5080 5081 // Mark const if we don't care about errno and that is the only 5082 // thing preventing the function from being const. This allows 5083 // IRgen to use LLVM intrinsics for such functions. 5084 if (!getLangOptions().MathErrno && 5085 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5086 if (!FD->getAttr<ConstAttr>()) 5087 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5088 } 5089 5090 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5091 FD->setType(Context.getNoReturnType(FD->getType())); 5092 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5093 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5094 if (Context.BuiltinInfo.isConst(BuiltinID)) 5095 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5096 } 5097 5098 IdentifierInfo *Name = FD->getIdentifier(); 5099 if (!Name) 5100 return; 5101 if ((!getLangOptions().CPlusPlus && 5102 FD->getDeclContext()->isTranslationUnit()) || 5103 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5104 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5105 LinkageSpecDecl::lang_c)) { 5106 // Okay: this could be a libc/libm/Objective-C function we know 5107 // about. 5108 } else 5109 return; 5110 5111 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5112 // FIXME: NSLog and NSLogv should be target specific 5113 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5114 // FIXME: We known better than our headers. 5115 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5116 } else 5117 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5118 "printf", 1, 5119 Name->isStr("NSLogv") ? 0 : 2)); 5120 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5121 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5122 // target-specific builtins, perhaps? 5123 if (!FD->getAttr<FormatAttr>()) 5124 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5125 "printf", 2, 5126 Name->isStr("vasprintf") ? 0 : 3)); 5127 } 5128} 5129 5130TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5131 TypeSourceInfo *TInfo) { 5132 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5133 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5134 5135 if (!TInfo) { 5136 assert(D.isInvalidType() && "no declarator info for valid type"); 5137 TInfo = Context.getTrivialTypeSourceInfo(T); 5138 } 5139 5140 // Scope manipulation handled by caller. 5141 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5142 D.getIdentifierLoc(), 5143 D.getIdentifier(), 5144 TInfo); 5145 5146 if (const TagType *TT = T->getAs<TagType>()) { 5147 TagDecl *TD = TT->getDecl(); 5148 5149 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5150 // keep track of the TypedefDecl. 5151 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5152 TD->setTypedefForAnonDecl(NewTD); 5153 } 5154 5155 if (D.isInvalidType()) 5156 NewTD->setInvalidDecl(); 5157 return NewTD; 5158} 5159 5160 5161/// \brief Determine whether a tag with a given kind is acceptable 5162/// as a redeclaration of the given tag declaration. 5163/// 5164/// \returns true if the new tag kind is acceptable, false otherwise. 5165bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5166 TagTypeKind NewTag, 5167 SourceLocation NewTagLoc, 5168 const IdentifierInfo &Name) { 5169 // C++ [dcl.type.elab]p3: 5170 // The class-key or enum keyword present in the 5171 // elaborated-type-specifier shall agree in kind with the 5172 // declaration to which the name in the elaborated-type-specifier 5173 // refers. This rule also applies to the form of 5174 // elaborated-type-specifier that declares a class-name or 5175 // friend class since it can be construed as referring to the 5176 // definition of the class. Thus, in any 5177 // elaborated-type-specifier, the enum keyword shall be used to 5178 // refer to an enumeration (7.2), the union class-key shall be 5179 // used to refer to a union (clause 9), and either the class or 5180 // struct class-key shall be used to refer to a class (clause 9) 5181 // declared using the class or struct class-key. 5182 TagTypeKind OldTag = Previous->getTagKind(); 5183 if (OldTag == NewTag) 5184 return true; 5185 5186 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5187 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5188 // Warn about the struct/class tag mismatch. 5189 bool isTemplate = false; 5190 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5191 isTemplate = Record->getDescribedClassTemplate(); 5192 5193 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5194 << (NewTag == TTK_Class) 5195 << isTemplate << &Name 5196 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5197 OldTag == TTK_Class? "class" : "struct"); 5198 Diag(Previous->getLocation(), diag::note_previous_use); 5199 return true; 5200 } 5201 return false; 5202} 5203 5204/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5205/// former case, Name will be non-null. In the later case, Name will be null. 5206/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5207/// reference/declaration/definition of a tag. 5208Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5209 SourceLocation KWLoc, CXXScopeSpec &SS, 5210 IdentifierInfo *Name, SourceLocation NameLoc, 5211 AttributeList *Attr, AccessSpecifier AS, 5212 MultiTemplateParamsArg TemplateParameterLists, 5213 bool &OwnedDecl, bool &IsDependent) { 5214 // If this is not a definition, it must have a name. 5215 assert((Name != 0 || TUK == TUK_Definition) && 5216 "Nameless record must be a definition!"); 5217 5218 OwnedDecl = false; 5219 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5220 5221 // FIXME: Check explicit specializations more carefully. 5222 bool isExplicitSpecialization = false; 5223 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5224 bool Invalid = false; 5225 if (TUK != TUK_Reference) { 5226 if (TemplateParameterList *TemplateParams 5227 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5228 (TemplateParameterList**)TemplateParameterLists.get(), 5229 TemplateParameterLists.size(), 5230 TUK == TUK_Friend, 5231 isExplicitSpecialization, 5232 Invalid)) { 5233 // All but one template parameter lists have been matching. 5234 --NumMatchedTemplateParamLists; 5235 5236 if (TemplateParams->size() > 0) { 5237 // This is a declaration or definition of a class template (which may 5238 // be a member of another template). 5239 if (Invalid) 5240 return 0; 5241 5242 OwnedDecl = false; 5243 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5244 SS, Name, NameLoc, Attr, 5245 TemplateParams, 5246 AS); 5247 TemplateParameterLists.release(); 5248 return Result.get(); 5249 } else { 5250 // The "template<>" header is extraneous. 5251 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5252 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5253 isExplicitSpecialization = true; 5254 } 5255 } 5256 } 5257 5258 DeclContext *SearchDC = CurContext; 5259 DeclContext *DC = CurContext; 5260 bool isStdBadAlloc = false; 5261 5262 RedeclarationKind Redecl = ForRedeclaration; 5263 if (TUK == TUK_Friend || TUK == TUK_Reference) 5264 Redecl = NotForRedeclaration; 5265 5266 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5267 5268 if (Name && SS.isNotEmpty()) { 5269 // We have a nested-name tag ('struct foo::bar'). 5270 5271 // Check for invalid 'foo::'. 5272 if (SS.isInvalid()) { 5273 Name = 0; 5274 goto CreateNewDecl; 5275 } 5276 5277 // If this is a friend or a reference to a class in a dependent 5278 // context, don't try to make a decl for it. 5279 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5280 DC = computeDeclContext(SS, false); 5281 if (!DC) { 5282 IsDependent = true; 5283 return 0; 5284 } 5285 } else { 5286 DC = computeDeclContext(SS, true); 5287 if (!DC) { 5288 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5289 << SS.getRange(); 5290 return 0; 5291 } 5292 } 5293 5294 if (RequireCompleteDeclContext(SS, DC)) 5295 return 0; 5296 5297 SearchDC = DC; 5298 // Look-up name inside 'foo::'. 5299 LookupQualifiedName(Previous, DC); 5300 5301 if (Previous.isAmbiguous()) 5302 return 0; 5303 5304 if (Previous.empty()) { 5305 // Name lookup did not find anything. However, if the 5306 // nested-name-specifier refers to the current instantiation, 5307 // and that current instantiation has any dependent base 5308 // classes, we might find something at instantiation time: treat 5309 // this as a dependent elaborated-type-specifier. 5310 if (Previous.wasNotFoundInCurrentInstantiation()) { 5311 IsDependent = true; 5312 return 0; 5313 } 5314 5315 // A tag 'foo::bar' must already exist. 5316 Diag(NameLoc, diag::err_not_tag_in_scope) 5317 << Kind << Name << DC << SS.getRange(); 5318 Name = 0; 5319 Invalid = true; 5320 goto CreateNewDecl; 5321 } 5322 } else if (Name) { 5323 // If this is a named struct, check to see if there was a previous forward 5324 // declaration or definition. 5325 // FIXME: We're looking into outer scopes here, even when we 5326 // shouldn't be. Doing so can result in ambiguities that we 5327 // shouldn't be diagnosing. 5328 LookupName(Previous, S); 5329 5330 // Note: there used to be some attempt at recovery here. 5331 if (Previous.isAmbiguous()) 5332 return 0; 5333 5334 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5335 // FIXME: This makes sure that we ignore the contexts associated 5336 // with C structs, unions, and enums when looking for a matching 5337 // tag declaration or definition. See the similar lookup tweak 5338 // in Sema::LookupName; is there a better way to deal with this? 5339 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5340 SearchDC = SearchDC->getParent(); 5341 } 5342 } 5343 5344 if (Previous.isSingleResult() && 5345 Previous.getFoundDecl()->isTemplateParameter()) { 5346 // Maybe we will complain about the shadowed template parameter. 5347 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5348 // Just pretend that we didn't see the previous declaration. 5349 Previous.clear(); 5350 } 5351 5352 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5353 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5354 // This is a declaration of or a reference to "std::bad_alloc". 5355 isStdBadAlloc = true; 5356 5357 if (Previous.empty() && StdBadAlloc) { 5358 // std::bad_alloc has been implicitly declared (but made invisible to 5359 // name lookup). Fill in this implicit declaration as the previous 5360 // declaration, so that the declarations get chained appropriately. 5361 Previous.addDecl(getStdBadAlloc()); 5362 } 5363 } 5364 5365 // If we didn't find a previous declaration, and this is a reference 5366 // (or friend reference), move to the correct scope. In C++, we 5367 // also need to do a redeclaration lookup there, just in case 5368 // there's a shadow friend decl. 5369 if (Name && Previous.empty() && 5370 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5371 if (Invalid) goto CreateNewDecl; 5372 assert(SS.isEmpty()); 5373 5374 if (TUK == TUK_Reference) { 5375 // C++ [basic.scope.pdecl]p5: 5376 // -- for an elaborated-type-specifier of the form 5377 // 5378 // class-key identifier 5379 // 5380 // if the elaborated-type-specifier is used in the 5381 // decl-specifier-seq or parameter-declaration-clause of a 5382 // function defined in namespace scope, the identifier is 5383 // declared as a class-name in the namespace that contains 5384 // the declaration; otherwise, except as a friend 5385 // declaration, the identifier is declared in the smallest 5386 // non-class, non-function-prototype scope that contains the 5387 // declaration. 5388 // 5389 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5390 // C structs and unions. 5391 // 5392 // It is an error in C++ to declare (rather than define) an enum 5393 // type, including via an elaborated type specifier. We'll 5394 // diagnose that later; for now, declare the enum in the same 5395 // scope as we would have picked for any other tag type. 5396 // 5397 // GNU C also supports this behavior as part of its incomplete 5398 // enum types extension, while GNU C++ does not. 5399 // 5400 // Find the context where we'll be declaring the tag. 5401 // FIXME: We would like to maintain the current DeclContext as the 5402 // lexical context, 5403 while (SearchDC->isRecord()) 5404 SearchDC = SearchDC->getParent(); 5405 5406 // Find the scope where we'll be declaring the tag. 5407 while (S->isClassScope() || 5408 (getLangOptions().CPlusPlus && 5409 S->isFunctionPrototypeScope()) || 5410 ((S->getFlags() & Scope::DeclScope) == 0) || 5411 (S->getEntity() && 5412 ((DeclContext *)S->getEntity())->isTransparentContext())) 5413 S = S->getParent(); 5414 } else { 5415 assert(TUK == TUK_Friend); 5416 // C++ [namespace.memdef]p3: 5417 // If a friend declaration in a non-local class first declares a 5418 // class or function, the friend class or function is a member of 5419 // the innermost enclosing namespace. 5420 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5421 } 5422 5423 // In C++, we need to do a redeclaration lookup to properly 5424 // diagnose some problems. 5425 if (getLangOptions().CPlusPlus) { 5426 Previous.setRedeclarationKind(ForRedeclaration); 5427 LookupQualifiedName(Previous, SearchDC); 5428 } 5429 } 5430 5431 if (!Previous.empty()) { 5432 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5433 5434 // It's okay to have a tag decl in the same scope as a typedef 5435 // which hides a tag decl in the same scope. Finding this 5436 // insanity with a redeclaration lookup can only actually happen 5437 // in C++. 5438 // 5439 // This is also okay for elaborated-type-specifiers, which is 5440 // technically forbidden by the current standard but which is 5441 // okay according to the likely resolution of an open issue; 5442 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5443 if (getLangOptions().CPlusPlus) { 5444 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5445 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5446 TagDecl *Tag = TT->getDecl(); 5447 if (Tag->getDeclName() == Name && 5448 Tag->getDeclContext()->getLookupContext() 5449 ->Equals(TD->getDeclContext()->getLookupContext())) { 5450 PrevDecl = Tag; 5451 Previous.clear(); 5452 Previous.addDecl(Tag); 5453 } 5454 } 5455 } 5456 } 5457 5458 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5459 // If this is a use of a previous tag, or if the tag is already declared 5460 // in the same scope (so that the definition/declaration completes or 5461 // rementions the tag), reuse the decl. 5462 if (TUK == TUK_Reference || TUK == TUK_Friend || 5463 isDeclInScope(PrevDecl, SearchDC, S)) { 5464 // Make sure that this wasn't declared as an enum and now used as a 5465 // struct or something similar. 5466 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5467 bool SafeToContinue 5468 = (PrevTagDecl->getTagKind() != TTK_Enum && 5469 Kind != TTK_Enum); 5470 if (SafeToContinue) 5471 Diag(KWLoc, diag::err_use_with_wrong_tag) 5472 << Name 5473 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5474 PrevTagDecl->getKindName()); 5475 else 5476 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5477 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5478 5479 if (SafeToContinue) 5480 Kind = PrevTagDecl->getTagKind(); 5481 else { 5482 // Recover by making this an anonymous redefinition. 5483 Name = 0; 5484 Previous.clear(); 5485 Invalid = true; 5486 } 5487 } 5488 5489 if (!Invalid) { 5490 // If this is a use, just return the declaration we found. 5491 5492 // FIXME: In the future, return a variant or some other clue 5493 // for the consumer of this Decl to know it doesn't own it. 5494 // For our current ASTs this shouldn't be a problem, but will 5495 // need to be changed with DeclGroups. 5496 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5497 TUK == TUK_Friend) 5498 return PrevTagDecl; 5499 5500 // Diagnose attempts to redefine a tag. 5501 if (TUK == TUK_Definition) { 5502 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5503 // If we're defining a specialization and the previous definition 5504 // is from an implicit instantiation, don't emit an error 5505 // here; we'll catch this in the general case below. 5506 if (!isExplicitSpecialization || 5507 !isa<CXXRecordDecl>(Def) || 5508 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5509 == TSK_ExplicitSpecialization) { 5510 Diag(NameLoc, diag::err_redefinition) << Name; 5511 Diag(Def->getLocation(), diag::note_previous_definition); 5512 // If this is a redefinition, recover by making this 5513 // struct be anonymous, which will make any later 5514 // references get the previous definition. 5515 Name = 0; 5516 Previous.clear(); 5517 Invalid = true; 5518 } 5519 } else { 5520 // If the type is currently being defined, complain 5521 // about a nested redefinition. 5522 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5523 if (Tag->isBeingDefined()) { 5524 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5525 Diag(PrevTagDecl->getLocation(), 5526 diag::note_previous_definition); 5527 Name = 0; 5528 Previous.clear(); 5529 Invalid = true; 5530 } 5531 } 5532 5533 // Okay, this is definition of a previously declared or referenced 5534 // tag PrevDecl. We're going to create a new Decl for it. 5535 } 5536 } 5537 // If we get here we have (another) forward declaration or we 5538 // have a definition. Just create a new decl. 5539 5540 } else { 5541 // If we get here, this is a definition of a new tag type in a nested 5542 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5543 // new decl/type. We set PrevDecl to NULL so that the entities 5544 // have distinct types. 5545 Previous.clear(); 5546 } 5547 // If we get here, we're going to create a new Decl. If PrevDecl 5548 // is non-NULL, it's a definition of the tag declared by 5549 // PrevDecl. If it's NULL, we have a new definition. 5550 5551 5552 // Otherwise, PrevDecl is not a tag, but was found with tag 5553 // lookup. This is only actually possible in C++, where a few 5554 // things like templates still live in the tag namespace. 5555 } else { 5556 assert(getLangOptions().CPlusPlus); 5557 5558 // Use a better diagnostic if an elaborated-type-specifier 5559 // found the wrong kind of type on the first 5560 // (non-redeclaration) lookup. 5561 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5562 !Previous.isForRedeclaration()) { 5563 unsigned Kind = 0; 5564 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5565 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5566 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5567 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5568 Invalid = true; 5569 5570 // Otherwise, only diagnose if the declaration is in scope. 5571 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5572 // do nothing 5573 5574 // Diagnose implicit declarations introduced by elaborated types. 5575 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5576 unsigned Kind = 0; 5577 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5578 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5579 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5580 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5581 Invalid = true; 5582 5583 // Otherwise it's a declaration. Call out a particularly common 5584 // case here. 5585 } else if (isa<TypedefDecl>(PrevDecl)) { 5586 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5587 << Name 5588 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5589 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5590 Invalid = true; 5591 5592 // Otherwise, diagnose. 5593 } else { 5594 // The tag name clashes with something else in the target scope, 5595 // issue an error and recover by making this tag be anonymous. 5596 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5597 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5598 Name = 0; 5599 Invalid = true; 5600 } 5601 5602 // The existing declaration isn't relevant to us; we're in a 5603 // new scope, so clear out the previous declaration. 5604 Previous.clear(); 5605 } 5606 } 5607 5608CreateNewDecl: 5609 5610 TagDecl *PrevDecl = 0; 5611 if (Previous.isSingleResult()) 5612 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5613 5614 // If there is an identifier, use the location of the identifier as the 5615 // location of the decl, otherwise use the location of the struct/union 5616 // keyword. 5617 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5618 5619 // Otherwise, create a new declaration. If there is a previous 5620 // declaration of the same entity, the two will be linked via 5621 // PrevDecl. 5622 TagDecl *New; 5623 5624 if (Kind == TTK_Enum) { 5625 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5626 // enum X { A, B, C } D; D should chain to X. 5627 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5628 cast_or_null<EnumDecl>(PrevDecl)); 5629 // If this is an undefined enum, warn. 5630 if (TUK != TUK_Definition && !Invalid) { 5631 TagDecl *Def; 5632 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5633 Diag(Loc, diag::ext_forward_ref_enum_def) 5634 << New; 5635 Diag(Def->getLocation(), diag::note_previous_definition); 5636 } else { 5637 Diag(Loc, 5638 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5639 : diag::ext_forward_ref_enum); 5640 } 5641 } 5642 } else { 5643 // struct/union/class 5644 5645 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5646 // struct X { int A; } D; D should chain to X. 5647 if (getLangOptions().CPlusPlus) { 5648 // FIXME: Look for a way to use RecordDecl for simple structs. 5649 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5650 cast_or_null<CXXRecordDecl>(PrevDecl)); 5651 5652 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5653 StdBadAlloc = cast<CXXRecordDecl>(New); 5654 } else 5655 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5656 cast_or_null<RecordDecl>(PrevDecl)); 5657 } 5658 5659 // Maybe add qualifier info. 5660 if (SS.isNotEmpty()) { 5661 if (SS.isSet()) { 5662 NestedNameSpecifier *NNS 5663 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5664 New->setQualifierInfo(NNS, SS.getRange()); 5665 if (NumMatchedTemplateParamLists > 0) { 5666 New->setTemplateParameterListsInfo(Context, 5667 NumMatchedTemplateParamLists, 5668 (TemplateParameterList**) TemplateParameterLists.release()); 5669 } 5670 } 5671 else 5672 Invalid = true; 5673 } 5674 5675 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5676 // Add alignment attributes if necessary; these attributes are checked when 5677 // the ASTContext lays out the structure. 5678 // 5679 // It is important for implementing the correct semantics that this 5680 // happen here (in act on tag decl). The #pragma pack stack is 5681 // maintained as a result of parser callbacks which can occur at 5682 // many points during the parsing of a struct declaration (because 5683 // the #pragma tokens are effectively skipped over during the 5684 // parsing of the struct). 5685 AddAlignmentAttributesForRecord(RD); 5686 } 5687 5688 // If this is a specialization of a member class (of a class template), 5689 // check the specialization. 5690 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5691 Invalid = true; 5692 5693 if (Invalid) 5694 New->setInvalidDecl(); 5695 5696 if (Attr) 5697 ProcessDeclAttributeList(S, New, Attr); 5698 5699 // If we're declaring or defining a tag in function prototype scope 5700 // in C, note that this type can only be used within the function. 5701 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5702 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5703 5704 // Set the lexical context. If the tag has a C++ scope specifier, the 5705 // lexical context will be different from the semantic context. 5706 New->setLexicalDeclContext(CurContext); 5707 5708 // Mark this as a friend decl if applicable. 5709 if (TUK == TUK_Friend) 5710 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5711 5712 // Set the access specifier. 5713 if (!Invalid && SearchDC->isRecord()) 5714 SetMemberAccessSpecifier(New, PrevDecl, AS); 5715 5716 if (TUK == TUK_Definition) 5717 New->startDefinition(); 5718 5719 // If this has an identifier, add it to the scope stack. 5720 if (TUK == TUK_Friend) { 5721 // We might be replacing an existing declaration in the lookup tables; 5722 // if so, borrow its access specifier. 5723 if (PrevDecl) 5724 New->setAccess(PrevDecl->getAccess()); 5725 5726 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5727 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5728 if (Name) // can be null along some error paths 5729 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5730 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5731 } else if (Name) { 5732 S = getNonFieldDeclScope(S); 5733 PushOnScopeChains(New, S); 5734 } else { 5735 CurContext->addDecl(New); 5736 } 5737 5738 // If this is the C FILE type, notify the AST context. 5739 if (IdentifierInfo *II = New->getIdentifier()) 5740 if (!New->isInvalidDecl() && 5741 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5742 II->isStr("FILE")) 5743 Context.setFILEDecl(New); 5744 5745 OwnedDecl = true; 5746 return New; 5747} 5748 5749void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 5750 AdjustDeclIfTemplate(TagD); 5751 TagDecl *Tag = cast<TagDecl>(TagD); 5752 5753 // Enter the tag context. 5754 PushDeclContext(S, Tag); 5755} 5756 5757void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 5758 SourceLocation LBraceLoc) { 5759 AdjustDeclIfTemplate(TagD); 5760 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 5761 5762 FieldCollector->StartClass(); 5763 5764 if (!Record->getIdentifier()) 5765 return; 5766 5767 // C++ [class]p2: 5768 // [...] The class-name is also inserted into the scope of the 5769 // class itself; this is known as the injected-class-name. For 5770 // purposes of access checking, the injected-class-name is treated 5771 // as if it were a public member name. 5772 CXXRecordDecl *InjectedClassName 5773 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5774 CurContext, Record->getLocation(), 5775 Record->getIdentifier(), 5776 Record->getTagKeywordLoc(), 5777 Record); 5778 InjectedClassName->setImplicit(); 5779 InjectedClassName->setAccess(AS_public); 5780 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5781 InjectedClassName->setDescribedClassTemplate(Template); 5782 PushOnScopeChains(InjectedClassName, S); 5783 assert(InjectedClassName->isInjectedClassName() && 5784 "Broken injected-class-name"); 5785} 5786 5787void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 5788 SourceLocation RBraceLoc) { 5789 AdjustDeclIfTemplate(TagD); 5790 TagDecl *Tag = cast<TagDecl>(TagD); 5791 Tag->setRBraceLoc(RBraceLoc); 5792 5793 if (isa<CXXRecordDecl>(Tag)) 5794 FieldCollector->FinishClass(); 5795 5796 // Exit this scope of this tag's definition. 5797 PopDeclContext(); 5798 5799 // Notify the consumer that we've defined a tag. 5800 Consumer.HandleTagDeclDefinition(Tag); 5801} 5802 5803void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 5804 AdjustDeclIfTemplate(TagD); 5805 TagDecl *Tag = cast<TagDecl>(TagD); 5806 Tag->setInvalidDecl(); 5807 5808 // We're undoing ActOnTagStartDefinition here, not 5809 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5810 // the FieldCollector. 5811 5812 PopDeclContext(); 5813} 5814 5815// Note that FieldName may be null for anonymous bitfields. 5816bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5817 QualType FieldTy, const Expr *BitWidth, 5818 bool *ZeroWidth) { 5819 // Default to true; that shouldn't confuse checks for emptiness 5820 if (ZeroWidth) 5821 *ZeroWidth = true; 5822 5823 // C99 6.7.2.1p4 - verify the field type. 5824 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5825 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5826 // Handle incomplete types with specific error. 5827 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5828 return true; 5829 if (FieldName) 5830 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5831 << FieldName << FieldTy << BitWidth->getSourceRange(); 5832 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5833 << FieldTy << BitWidth->getSourceRange(); 5834 } 5835 5836 // If the bit-width is type- or value-dependent, don't try to check 5837 // it now. 5838 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5839 return false; 5840 5841 llvm::APSInt Value; 5842 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5843 return true; 5844 5845 if (Value != 0 && ZeroWidth) 5846 *ZeroWidth = false; 5847 5848 // Zero-width bitfield is ok for anonymous field. 5849 if (Value == 0 && FieldName) 5850 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5851 5852 if (Value.isSigned() && Value.isNegative()) { 5853 if (FieldName) 5854 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5855 << FieldName << Value.toString(10); 5856 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5857 << Value.toString(10); 5858 } 5859 5860 if (!FieldTy->isDependentType()) { 5861 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5862 if (Value.getZExtValue() > TypeSize) { 5863 if (!getLangOptions().CPlusPlus) { 5864 if (FieldName) 5865 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5866 << FieldName << (unsigned)Value.getZExtValue() 5867 << (unsigned)TypeSize; 5868 5869 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5870 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5871 } 5872 5873 if (FieldName) 5874 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5875 << FieldName << (unsigned)Value.getZExtValue() 5876 << (unsigned)TypeSize; 5877 else 5878 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5879 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5880 } 5881 } 5882 5883 return false; 5884} 5885 5886/// ActOnField - Each field of a struct/union/class is passed into this in order 5887/// to create a FieldDecl object for it. 5888Decl *Sema::ActOnField(Scope *S, Decl *TagD, 5889 SourceLocation DeclStart, 5890 Declarator &D, ExprTy *BitfieldWidth) { 5891 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 5892 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5893 AS_public); 5894 return Res; 5895} 5896 5897/// HandleField - Analyze a field of a C struct or a C++ data member. 5898/// 5899FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5900 SourceLocation DeclStart, 5901 Declarator &D, Expr *BitWidth, 5902 AccessSpecifier AS) { 5903 IdentifierInfo *II = D.getIdentifier(); 5904 SourceLocation Loc = DeclStart; 5905 if (II) Loc = D.getIdentifierLoc(); 5906 5907 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5908 QualType T = TInfo->getType(); 5909 if (getLangOptions().CPlusPlus) 5910 CheckExtraCXXDefaultArguments(D); 5911 5912 DiagnoseFunctionSpecifiers(D); 5913 5914 if (D.getDeclSpec().isThreadSpecified()) 5915 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5916 5917 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5918 ForRedeclaration); 5919 5920 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5921 // Maybe we will complain about the shadowed template parameter. 5922 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5923 // Just pretend that we didn't see the previous declaration. 5924 PrevDecl = 0; 5925 } 5926 5927 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5928 PrevDecl = 0; 5929 5930 bool Mutable 5931 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5932 SourceLocation TSSL = D.getSourceRange().getBegin(); 5933 FieldDecl *NewFD 5934 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5935 AS, PrevDecl, &D); 5936 5937 if (NewFD->isInvalidDecl()) 5938 Record->setInvalidDecl(); 5939 5940 if (NewFD->isInvalidDecl() && PrevDecl) { 5941 // Don't introduce NewFD into scope; there's already something 5942 // with the same name in the same scope. 5943 } else if (II) { 5944 PushOnScopeChains(NewFD, S); 5945 } else 5946 Record->addDecl(NewFD); 5947 5948 return NewFD; 5949} 5950 5951/// \brief Build a new FieldDecl and check its well-formedness. 5952/// 5953/// This routine builds a new FieldDecl given the fields name, type, 5954/// record, etc. \p PrevDecl should refer to any previous declaration 5955/// with the same name and in the same scope as the field to be 5956/// created. 5957/// 5958/// \returns a new FieldDecl. 5959/// 5960/// \todo The Declarator argument is a hack. It will be removed once 5961FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5962 TypeSourceInfo *TInfo, 5963 RecordDecl *Record, SourceLocation Loc, 5964 bool Mutable, Expr *BitWidth, 5965 SourceLocation TSSL, 5966 AccessSpecifier AS, NamedDecl *PrevDecl, 5967 Declarator *D) { 5968 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5969 bool InvalidDecl = false; 5970 if (D) InvalidDecl = D->isInvalidType(); 5971 5972 // If we receive a broken type, recover by assuming 'int' and 5973 // marking this declaration as invalid. 5974 if (T.isNull()) { 5975 InvalidDecl = true; 5976 T = Context.IntTy; 5977 } 5978 5979 QualType EltTy = Context.getBaseElementType(T); 5980 if (!EltTy->isDependentType() && 5981 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 5982 // Fields of incomplete type force their record to be invalid. 5983 Record->setInvalidDecl(); 5984 InvalidDecl = true; 5985 } 5986 5987 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5988 // than a variably modified type. 5989 if (!InvalidDecl && T->isVariablyModifiedType()) { 5990 bool SizeIsNegative; 5991 llvm::APSInt Oversized; 5992 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5993 SizeIsNegative, 5994 Oversized); 5995 if (!FixedTy.isNull()) { 5996 Diag(Loc, diag::warn_illegal_constant_array_size); 5997 T = FixedTy; 5998 } else { 5999 if (SizeIsNegative) 6000 Diag(Loc, diag::err_typecheck_negative_array_size); 6001 else if (Oversized.getBoolValue()) 6002 Diag(Loc, diag::err_array_too_large) 6003 << Oversized.toString(10); 6004 else 6005 Diag(Loc, diag::err_typecheck_field_variable_size); 6006 InvalidDecl = true; 6007 } 6008 } 6009 6010 // Fields can not have abstract class types 6011 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6012 diag::err_abstract_type_in_decl, 6013 AbstractFieldType)) 6014 InvalidDecl = true; 6015 6016 bool ZeroWidth = false; 6017 // If this is declared as a bit-field, check the bit-field. 6018 if (!InvalidDecl && BitWidth && 6019 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6020 InvalidDecl = true; 6021 DeleteExpr(BitWidth); 6022 BitWidth = 0; 6023 ZeroWidth = false; 6024 } 6025 6026 // Check that 'mutable' is consistent with the type of the declaration. 6027 if (!InvalidDecl && Mutable) { 6028 unsigned DiagID = 0; 6029 if (T->isReferenceType()) 6030 DiagID = diag::err_mutable_reference; 6031 else if (T.isConstQualified()) 6032 DiagID = diag::err_mutable_const; 6033 6034 if (DiagID) { 6035 SourceLocation ErrLoc = Loc; 6036 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6037 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6038 Diag(ErrLoc, DiagID); 6039 Mutable = false; 6040 InvalidDecl = true; 6041 } 6042 } 6043 6044 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6045 BitWidth, Mutable); 6046 if (InvalidDecl) 6047 NewFD->setInvalidDecl(); 6048 6049 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6050 Diag(Loc, diag::err_duplicate_member) << II; 6051 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6052 NewFD->setInvalidDecl(); 6053 } 6054 6055 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6056 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 6057 6058 if (!T->isPODType()) 6059 CXXRecord->setPOD(false); 6060 if (!ZeroWidth) 6061 CXXRecord->setEmpty(false); 6062 6063 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6064 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6065 if (RDecl->getDefinition()) { 6066 if (!RDecl->hasTrivialConstructor()) 6067 CXXRecord->setHasTrivialConstructor(false); 6068 if (!RDecl->hasTrivialCopyConstructor()) 6069 CXXRecord->setHasTrivialCopyConstructor(false); 6070 if (!RDecl->hasTrivialCopyAssignment()) 6071 CXXRecord->setHasTrivialCopyAssignment(false); 6072 if (!RDecl->hasTrivialDestructor()) 6073 CXXRecord->setHasTrivialDestructor(false); 6074 6075 // C++ 9.5p1: An object of a class with a non-trivial 6076 // constructor, a non-trivial copy constructor, a non-trivial 6077 // destructor, or a non-trivial copy assignment operator 6078 // cannot be a member of a union, nor can an array of such 6079 // objects. 6080 // TODO: C++0x alters this restriction significantly. 6081 if (Record->isUnion() && CheckNontrivialField(NewFD)) 6082 NewFD->setInvalidDecl(); 6083 } 6084 } 6085 } 6086 6087 // FIXME: We need to pass in the attributes given an AST 6088 // representation, not a parser representation. 6089 if (D) 6090 // FIXME: What to pass instead of TUScope? 6091 ProcessDeclAttributes(TUScope, NewFD, *D); 6092 6093 if (T.isObjCGCWeak()) 6094 Diag(Loc, diag::warn_attribute_weak_on_field); 6095 6096 NewFD->setAccess(AS); 6097 6098 // C++ [dcl.init.aggr]p1: 6099 // An aggregate is an array or a class (clause 9) with [...] no 6100 // private or protected non-static data members (clause 11). 6101 // A POD must be an aggregate. 6102 if (getLangOptions().CPlusPlus && 6103 (AS == AS_private || AS == AS_protected)) { 6104 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 6105 CXXRecord->setAggregate(false); 6106 CXXRecord->setPOD(false); 6107 } 6108 6109 return NewFD; 6110} 6111 6112bool Sema::CheckNontrivialField(FieldDecl *FD) { 6113 assert(FD); 6114 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6115 6116 if (FD->isInvalidDecl()) 6117 return true; 6118 6119 QualType EltTy = Context.getBaseElementType(FD->getType()); 6120 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6121 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6122 if (RDecl->getDefinition()) { 6123 // We check for copy constructors before constructors 6124 // because otherwise we'll never get complaints about 6125 // copy constructors. 6126 6127 CXXSpecialMember member = CXXInvalid; 6128 if (!RDecl->hasTrivialCopyConstructor()) 6129 member = CXXCopyConstructor; 6130 else if (!RDecl->hasTrivialConstructor()) 6131 member = CXXConstructor; 6132 else if (!RDecl->hasTrivialCopyAssignment()) 6133 member = CXXCopyAssignment; 6134 else if (!RDecl->hasTrivialDestructor()) 6135 member = CXXDestructor; 6136 6137 if (member != CXXInvalid) { 6138 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 6139 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 6140 DiagnoseNontrivial(RT, member); 6141 return true; 6142 } 6143 } 6144 } 6145 6146 return false; 6147} 6148 6149/// DiagnoseNontrivial - Given that a class has a non-trivial 6150/// special member, figure out why. 6151void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6152 QualType QT(T, 0U); 6153 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6154 6155 // Check whether the member was user-declared. 6156 switch (member) { 6157 case CXXInvalid: 6158 break; 6159 6160 case CXXConstructor: 6161 if (RD->hasUserDeclaredConstructor()) { 6162 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6163 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6164 const FunctionDecl *body = 0; 6165 ci->hasBody(body); 6166 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6167 SourceLocation CtorLoc = ci->getLocation(); 6168 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6169 return; 6170 } 6171 } 6172 6173 assert(0 && "found no user-declared constructors"); 6174 return; 6175 } 6176 break; 6177 6178 case CXXCopyConstructor: 6179 if (RD->hasUserDeclaredCopyConstructor()) { 6180 SourceLocation CtorLoc = 6181 RD->getCopyConstructor(Context, 0)->getLocation(); 6182 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6183 return; 6184 } 6185 break; 6186 6187 case CXXCopyAssignment: 6188 if (RD->hasUserDeclaredCopyAssignment()) { 6189 // FIXME: this should use the location of the copy 6190 // assignment, not the type. 6191 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6192 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6193 return; 6194 } 6195 break; 6196 6197 case CXXDestructor: 6198 if (RD->hasUserDeclaredDestructor()) { 6199 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6200 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6201 return; 6202 } 6203 break; 6204 } 6205 6206 typedef CXXRecordDecl::base_class_iterator base_iter; 6207 6208 // Virtual bases and members inhibit trivial copying/construction, 6209 // but not trivial destruction. 6210 if (member != CXXDestructor) { 6211 // Check for virtual bases. vbases includes indirect virtual bases, 6212 // so we just iterate through the direct bases. 6213 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6214 if (bi->isVirtual()) { 6215 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6216 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6217 return; 6218 } 6219 6220 // Check for virtual methods. 6221 typedef CXXRecordDecl::method_iterator meth_iter; 6222 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6223 ++mi) { 6224 if (mi->isVirtual()) { 6225 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6226 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6227 return; 6228 } 6229 } 6230 } 6231 6232 bool (CXXRecordDecl::*hasTrivial)() const; 6233 switch (member) { 6234 case CXXConstructor: 6235 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6236 case CXXCopyConstructor: 6237 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6238 case CXXCopyAssignment: 6239 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6240 case CXXDestructor: 6241 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6242 default: 6243 assert(0 && "unexpected special member"); return; 6244 } 6245 6246 // Check for nontrivial bases (and recurse). 6247 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6248 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6249 assert(BaseRT && "Don't know how to handle dependent bases"); 6250 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6251 if (!(BaseRecTy->*hasTrivial)()) { 6252 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6253 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6254 DiagnoseNontrivial(BaseRT, member); 6255 return; 6256 } 6257 } 6258 6259 // Check for nontrivial members (and recurse). 6260 typedef RecordDecl::field_iterator field_iter; 6261 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6262 ++fi) { 6263 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6264 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6265 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6266 6267 if (!(EltRD->*hasTrivial)()) { 6268 SourceLocation FLoc = (*fi)->getLocation(); 6269 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6270 DiagnoseNontrivial(EltRT, member); 6271 return; 6272 } 6273 } 6274 } 6275 6276 assert(0 && "found no explanation for non-trivial member"); 6277} 6278 6279/// TranslateIvarVisibility - Translate visibility from a token ID to an 6280/// AST enum value. 6281static ObjCIvarDecl::AccessControl 6282TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6283 switch (ivarVisibility) { 6284 default: assert(0 && "Unknown visitibility kind"); 6285 case tok::objc_private: return ObjCIvarDecl::Private; 6286 case tok::objc_public: return ObjCIvarDecl::Public; 6287 case tok::objc_protected: return ObjCIvarDecl::Protected; 6288 case tok::objc_package: return ObjCIvarDecl::Package; 6289 } 6290} 6291 6292/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6293/// in order to create an IvarDecl object for it. 6294Decl *Sema::ActOnIvar(Scope *S, 6295 SourceLocation DeclStart, 6296 Decl *IntfDecl, 6297 Declarator &D, ExprTy *BitfieldWidth, 6298 tok::ObjCKeywordKind Visibility) { 6299 6300 IdentifierInfo *II = D.getIdentifier(); 6301 Expr *BitWidth = (Expr*)BitfieldWidth; 6302 SourceLocation Loc = DeclStart; 6303 if (II) Loc = D.getIdentifierLoc(); 6304 6305 // FIXME: Unnamed fields can be handled in various different ways, for 6306 // example, unnamed unions inject all members into the struct namespace! 6307 6308 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6309 QualType T = TInfo->getType(); 6310 6311 if (BitWidth) { 6312 // 6.7.2.1p3, 6.7.2.1p4 6313 if (VerifyBitField(Loc, II, T, BitWidth)) { 6314 D.setInvalidType(); 6315 DeleteExpr(BitWidth); 6316 BitWidth = 0; 6317 } 6318 } else { 6319 // Not a bitfield. 6320 6321 // validate II. 6322 6323 } 6324 if (T->isReferenceType()) { 6325 Diag(Loc, diag::err_ivar_reference_type); 6326 D.setInvalidType(); 6327 } 6328 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6329 // than a variably modified type. 6330 else if (T->isVariablyModifiedType()) { 6331 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6332 D.setInvalidType(); 6333 } 6334 6335 // Get the visibility (access control) for this ivar. 6336 ObjCIvarDecl::AccessControl ac = 6337 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6338 : ObjCIvarDecl::None; 6339 // Must set ivar's DeclContext to its enclosing interface. 6340 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 6341 ObjCContainerDecl *EnclosingContext; 6342 if (ObjCImplementationDecl *IMPDecl = 6343 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6344 if (!LangOpts.ObjCNonFragileABI2) { 6345 // Case of ivar declared in an implementation. Context is that of its class. 6346 EnclosingContext = IMPDecl->getClassInterface(); 6347 assert(EnclosingContext && "Implementation has no class interface!"); 6348 } 6349 else 6350 EnclosingContext = EnclosingDecl; 6351 } else { 6352 if (ObjCCategoryDecl *CDecl = 6353 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6354 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6355 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6356 return 0; 6357 } 6358 } 6359 EnclosingContext = EnclosingDecl; 6360 } 6361 6362 // Construct the decl. 6363 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6364 EnclosingContext, Loc, II, T, 6365 TInfo, ac, (Expr *)BitfieldWidth); 6366 6367 if (II) { 6368 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6369 ForRedeclaration); 6370 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6371 && !isa<TagDecl>(PrevDecl)) { 6372 Diag(Loc, diag::err_duplicate_member) << II; 6373 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6374 NewID->setInvalidDecl(); 6375 } 6376 } 6377 6378 // Process attributes attached to the ivar. 6379 ProcessDeclAttributes(S, NewID, D); 6380 6381 if (D.isInvalidType()) 6382 NewID->setInvalidDecl(); 6383 6384 if (II) { 6385 // FIXME: When interfaces are DeclContexts, we'll need to add 6386 // these to the interface. 6387 S->AddDecl(NewID); 6388 IdResolver.AddDecl(NewID); 6389 } 6390 6391 return NewID; 6392} 6393 6394/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 6395/// class and class extensions. For every class @interface and class 6396/// extension @interface, if the last ivar is a bitfield of any type, 6397/// then add an implicit `char :0` ivar to the end of that interface. 6398void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 6399 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 6400 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 6401 return; 6402 6403 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 6404 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 6405 6406 if (!Ivar->isBitField()) 6407 return; 6408 uint64_t BitFieldSize = 6409 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 6410 if (BitFieldSize == 0) 6411 return; 6412 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 6413 if (!ID) { 6414 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6415 if (!CD->IsClassExtension()) 6416 return; 6417 } 6418 // No need to add this to end of @implementation. 6419 else 6420 return; 6421 } 6422 // All conditions are met. Add a new bitfield to the tail end of ivars. 6423 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 6424 Expr * BW = 6425 new (Context) IntegerLiteral(Zero, Context.CharTy, DeclLoc); 6426 6427 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 6428 DeclLoc, 0, 6429 Context.CharTy, 6430 Context.CreateTypeSourceInfo(Context.CharTy), 6431 ObjCIvarDecl::Private, BW, 6432 true); 6433 AllIvarDecls.push_back(Ivar); 6434} 6435 6436void Sema::ActOnFields(Scope* S, 6437 SourceLocation RecLoc, Decl *EnclosingDecl, 6438 Decl **Fields, unsigned NumFields, 6439 SourceLocation LBrac, SourceLocation RBrac, 6440 AttributeList *Attr) { 6441 assert(EnclosingDecl && "missing record or interface decl"); 6442 6443 // If the decl this is being inserted into is invalid, then it may be a 6444 // redeclaration or some other bogus case. Don't try to add fields to it. 6445 if (EnclosingDecl->isInvalidDecl()) { 6446 // FIXME: Deallocate fields? 6447 return; 6448 } 6449 6450 6451 // Verify that all the fields are okay. 6452 unsigned NumNamedMembers = 0; 6453 llvm::SmallVector<FieldDecl*, 32> RecFields; 6454 6455 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6456 for (unsigned i = 0; i != NumFields; ++i) { 6457 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 6458 6459 // Get the type for the field. 6460 Type *FDTy = FD->getType().getTypePtr(); 6461 6462 if (!FD->isAnonymousStructOrUnion()) { 6463 // Remember all fields written by the user. 6464 RecFields.push_back(FD); 6465 } 6466 6467 // If the field is already invalid for some reason, don't emit more 6468 // diagnostics about it. 6469 if (FD->isInvalidDecl()) { 6470 EnclosingDecl->setInvalidDecl(); 6471 continue; 6472 } 6473 6474 // C99 6.7.2.1p2: 6475 // A structure or union shall not contain a member with 6476 // incomplete or function type (hence, a structure shall not 6477 // contain an instance of itself, but may contain a pointer to 6478 // an instance of itself), except that the last member of a 6479 // structure with more than one named member may have incomplete 6480 // array type; such a structure (and any union containing, 6481 // possibly recursively, a member that is such a structure) 6482 // shall not be a member of a structure or an element of an 6483 // array. 6484 if (FDTy->isFunctionType()) { 6485 // Field declared as a function. 6486 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6487 << FD->getDeclName(); 6488 FD->setInvalidDecl(); 6489 EnclosingDecl->setInvalidDecl(); 6490 continue; 6491 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6492 Record && Record->isStruct()) { 6493 // Flexible array member. 6494 if (NumNamedMembers < 1) { 6495 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6496 << FD->getDeclName(); 6497 FD->setInvalidDecl(); 6498 EnclosingDecl->setInvalidDecl(); 6499 continue; 6500 } 6501 if (!FD->getType()->isDependentType() && 6502 !Context.getBaseElementType(FD->getType())->isPODType()) { 6503 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6504 << FD->getDeclName() << FD->getType(); 6505 FD->setInvalidDecl(); 6506 EnclosingDecl->setInvalidDecl(); 6507 continue; 6508 } 6509 6510 // Okay, we have a legal flexible array member at the end of the struct. 6511 if (Record) 6512 Record->setHasFlexibleArrayMember(true); 6513 } else if (!FDTy->isDependentType() && 6514 RequireCompleteType(FD->getLocation(), FD->getType(), 6515 diag::err_field_incomplete)) { 6516 // Incomplete type 6517 FD->setInvalidDecl(); 6518 EnclosingDecl->setInvalidDecl(); 6519 continue; 6520 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6521 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6522 // If this is a member of a union, then entire union becomes "flexible". 6523 if (Record && Record->isUnion()) { 6524 Record->setHasFlexibleArrayMember(true); 6525 } else { 6526 // If this is a struct/class and this is not the last element, reject 6527 // it. Note that GCC supports variable sized arrays in the middle of 6528 // structures. 6529 if (i != NumFields-1) 6530 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6531 << FD->getDeclName() << FD->getType(); 6532 else { 6533 // We support flexible arrays at the end of structs in 6534 // other structs as an extension. 6535 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6536 << FD->getDeclName(); 6537 if (Record) 6538 Record->setHasFlexibleArrayMember(true); 6539 } 6540 } 6541 } 6542 if (Record && FDTTy->getDecl()->hasObjectMember()) 6543 Record->setHasObjectMember(true); 6544 } else if (FDTy->isObjCObjectType()) { 6545 /// A field cannot be an Objective-c object 6546 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6547 FD->setInvalidDecl(); 6548 EnclosingDecl->setInvalidDecl(); 6549 continue; 6550 } else if (getLangOptions().ObjC1 && 6551 getLangOptions().getGCMode() != LangOptions::NonGC && 6552 Record && 6553 (FD->getType()->isObjCObjectPointerType() || 6554 FD->getType().isObjCGCStrong())) 6555 Record->setHasObjectMember(true); 6556 else if (Context.getAsArrayType(FD->getType())) { 6557 QualType BaseType = Context.getBaseElementType(FD->getType()); 6558 if (Record && BaseType->isRecordType() && 6559 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6560 Record->setHasObjectMember(true); 6561 } 6562 // Keep track of the number of named members. 6563 if (FD->getIdentifier()) 6564 ++NumNamedMembers; 6565 } 6566 6567 // Okay, we successfully defined 'Record'. 6568 if (Record) { 6569 Record->completeDefinition(); 6570 } else { 6571 ObjCIvarDecl **ClsFields = 6572 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6573 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6574 ID->setLocEnd(RBrac); 6575 // Add ivar's to class's DeclContext. 6576 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6577 ClsFields[i]->setLexicalDeclContext(ID); 6578 ID->addDecl(ClsFields[i]); 6579 } 6580 // Must enforce the rule that ivars in the base classes may not be 6581 // duplicates. 6582 if (ID->getSuperClass()) 6583 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6584 } else if (ObjCImplementationDecl *IMPDecl = 6585 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6586 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6587 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6588 // Ivar declared in @implementation never belongs to the implementation. 6589 // Only it is in implementation's lexical context. 6590 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6591 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6592 } else if (ObjCCategoryDecl *CDecl = 6593 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6594 // case of ivars in class extension; all other cases have been 6595 // reported as errors elsewhere. 6596 // FIXME. Class extension does not have a LocEnd field. 6597 // CDecl->setLocEnd(RBrac); 6598 // Add ivar's to class extension's DeclContext. 6599 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6600 ClsFields[i]->setLexicalDeclContext(CDecl); 6601 CDecl->addDecl(ClsFields[i]); 6602 } 6603 } 6604 } 6605 6606 if (Attr) 6607 ProcessDeclAttributeList(S, Record, Attr); 6608 6609 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6610 // set the visibility of this record. 6611 if (Record && !Record->getDeclContext()->isRecord()) 6612 AddPushedVisibilityAttribute(Record); 6613} 6614 6615/// \brief Determine whether the given integral value is representable within 6616/// the given type T. 6617static bool isRepresentableIntegerValue(ASTContext &Context, 6618 llvm::APSInt &Value, 6619 QualType T) { 6620 assert(T->isIntegralType(Context) && "Integral type required!"); 6621 unsigned BitWidth = Context.getIntWidth(T); 6622 6623 if (Value.isUnsigned() || Value.isNonNegative()) 6624 return Value.getActiveBits() < BitWidth; 6625 6626 return Value.getMinSignedBits() <= BitWidth; 6627} 6628 6629// \brief Given an integral type, return the next larger integral type 6630// (or a NULL type of no such type exists). 6631static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6632 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6633 // enum checking below. 6634 assert(T->isIntegralType(Context) && "Integral type required!"); 6635 const unsigned NumTypes = 4; 6636 QualType SignedIntegralTypes[NumTypes] = { 6637 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6638 }; 6639 QualType UnsignedIntegralTypes[NumTypes] = { 6640 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6641 Context.UnsignedLongLongTy 6642 }; 6643 6644 unsigned BitWidth = Context.getTypeSize(T); 6645 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6646 : UnsignedIntegralTypes; 6647 for (unsigned I = 0; I != NumTypes; ++I) 6648 if (Context.getTypeSize(Types[I]) > BitWidth) 6649 return Types[I]; 6650 6651 return QualType(); 6652} 6653 6654EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6655 EnumConstantDecl *LastEnumConst, 6656 SourceLocation IdLoc, 6657 IdentifierInfo *Id, 6658 Expr *Val) { 6659 unsigned IntWidth = Context.Target.getIntWidth(); 6660 llvm::APSInt EnumVal(IntWidth); 6661 QualType EltTy; 6662 if (Val) { 6663 if (Enum->isDependentType() || Val->isTypeDependent()) 6664 EltTy = Context.DependentTy; 6665 else { 6666 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6667 SourceLocation ExpLoc; 6668 if (!Val->isValueDependent() && 6669 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6670 Val = 0; 6671 } else { 6672 if (!getLangOptions().CPlusPlus) { 6673 // C99 6.7.2.2p2: 6674 // The expression that defines the value of an enumeration constant 6675 // shall be an integer constant expression that has a value 6676 // representable as an int. 6677 6678 // Complain if the value is not representable in an int. 6679 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6680 Diag(IdLoc, diag::ext_enum_value_not_int) 6681 << EnumVal.toString(10) << Val->getSourceRange() 6682 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6683 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6684 // Force the type of the expression to 'int'. 6685 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6686 } 6687 } 6688 6689 // C++0x [dcl.enum]p5: 6690 // If the underlying type is not fixed, the type of each enumerator 6691 // is the type of its initializing value: 6692 // - If an initializer is specified for an enumerator, the 6693 // initializing value has the same type as the expression. 6694 EltTy = Val->getType(); 6695 } 6696 } 6697 } 6698 6699 if (!Val) { 6700 if (Enum->isDependentType()) 6701 EltTy = Context.DependentTy; 6702 else if (!LastEnumConst) { 6703 // C++0x [dcl.enum]p5: 6704 // If the underlying type is not fixed, the type of each enumerator 6705 // is the type of its initializing value: 6706 // - If no initializer is specified for the first enumerator, the 6707 // initializing value has an unspecified integral type. 6708 // 6709 // GCC uses 'int' for its unspecified integral type, as does 6710 // C99 6.7.2.2p3. 6711 EltTy = Context.IntTy; 6712 } else { 6713 // Assign the last value + 1. 6714 EnumVal = LastEnumConst->getInitVal(); 6715 ++EnumVal; 6716 EltTy = LastEnumConst->getType(); 6717 6718 // Check for overflow on increment. 6719 if (EnumVal < LastEnumConst->getInitVal()) { 6720 // C++0x [dcl.enum]p5: 6721 // If the underlying type is not fixed, the type of each enumerator 6722 // is the type of its initializing value: 6723 // 6724 // - Otherwise the type of the initializing value is the same as 6725 // the type of the initializing value of the preceding enumerator 6726 // unless the incremented value is not representable in that type, 6727 // in which case the type is an unspecified integral type 6728 // sufficient to contain the incremented value. If no such type 6729 // exists, the program is ill-formed. 6730 QualType T = getNextLargerIntegralType(Context, EltTy); 6731 if (T.isNull()) { 6732 // There is no integral type larger enough to represent this 6733 // value. Complain, then allow the value to wrap around. 6734 EnumVal = LastEnumConst->getInitVal(); 6735 EnumVal.zext(EnumVal.getBitWidth() * 2); 6736 Diag(IdLoc, diag::warn_enumerator_too_large) 6737 << EnumVal.toString(10); 6738 } else { 6739 EltTy = T; 6740 } 6741 6742 // Retrieve the last enumerator's value, extent that type to the 6743 // type that is supposed to be large enough to represent the incremented 6744 // value, then increment. 6745 EnumVal = LastEnumConst->getInitVal(); 6746 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6747 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6748 ++EnumVal; 6749 6750 // If we're not in C++, diagnose the overflow of enumerator values, 6751 // which in C99 means that the enumerator value is not representable in 6752 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6753 // permits enumerator values that are representable in some larger 6754 // integral type. 6755 if (!getLangOptions().CPlusPlus && !T.isNull()) 6756 Diag(IdLoc, diag::warn_enum_value_overflow); 6757 } else if (!getLangOptions().CPlusPlus && 6758 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6759 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6760 Diag(IdLoc, diag::ext_enum_value_not_int) 6761 << EnumVal.toString(10) << 1; 6762 } 6763 } 6764 } 6765 6766 if (!EltTy->isDependentType()) { 6767 // Make the enumerator value match the signedness and size of the 6768 // enumerator's type. 6769 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6770 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6771 } 6772 6773 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6774 Val, EnumVal); 6775} 6776 6777 6778Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, 6779 Decl *lastEnumConst, 6780 SourceLocation IdLoc, 6781 IdentifierInfo *Id, 6782 SourceLocation EqualLoc, ExprTy *val) { 6783 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 6784 EnumConstantDecl *LastEnumConst = 6785 cast_or_null<EnumConstantDecl>(lastEnumConst); 6786 Expr *Val = static_cast<Expr*>(val); 6787 6788 // The scope passed in may not be a decl scope. Zip up the scope tree until 6789 // we find one that is. 6790 S = getNonFieldDeclScope(S); 6791 6792 // Verify that there isn't already something declared with this name in this 6793 // scope. 6794 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6795 ForRedeclaration); 6796 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6797 // Maybe we will complain about the shadowed template parameter. 6798 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6799 // Just pretend that we didn't see the previous declaration. 6800 PrevDecl = 0; 6801 } 6802 6803 if (PrevDecl) { 6804 // When in C++, we may get a TagDecl with the same name; in this case the 6805 // enum constant will 'hide' the tag. 6806 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6807 "Received TagDecl when not in C++!"); 6808 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6809 if (isa<EnumConstantDecl>(PrevDecl)) 6810 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6811 else 6812 Diag(IdLoc, diag::err_redefinition) << Id; 6813 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6814 return 0; 6815 } 6816 } 6817 6818 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6819 IdLoc, Id, Val); 6820 6821 // Register this decl in the current scope stack. 6822 if (New) { 6823 New->setAccess(TheEnumDecl->getAccess()); 6824 PushOnScopeChains(New, S); 6825 } 6826 6827 return New; 6828} 6829 6830void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6831 SourceLocation RBraceLoc, Decl *EnumDeclX, 6832 Decl **Elements, unsigned NumElements, 6833 Scope *S, AttributeList *Attr) { 6834 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 6835 QualType EnumType = Context.getTypeDeclType(Enum); 6836 6837 if (Attr) 6838 ProcessDeclAttributeList(S, Enum, Attr); 6839 6840 if (Enum->isDependentType()) { 6841 for (unsigned i = 0; i != NumElements; ++i) { 6842 EnumConstantDecl *ECD = 6843 cast_or_null<EnumConstantDecl>(Elements[i]); 6844 if (!ECD) continue; 6845 6846 ECD->setType(EnumType); 6847 } 6848 6849 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6850 return; 6851 } 6852 6853 // TODO: If the result value doesn't fit in an int, it must be a long or long 6854 // long value. ISO C does not support this, but GCC does as an extension, 6855 // emit a warning. 6856 unsigned IntWidth = Context.Target.getIntWidth(); 6857 unsigned CharWidth = Context.Target.getCharWidth(); 6858 unsigned ShortWidth = Context.Target.getShortWidth(); 6859 6860 // Verify that all the values are okay, compute the size of the values, and 6861 // reverse the list. 6862 unsigned NumNegativeBits = 0; 6863 unsigned NumPositiveBits = 0; 6864 6865 // Keep track of whether all elements have type int. 6866 bool AllElementsInt = true; 6867 6868 for (unsigned i = 0; i != NumElements; ++i) { 6869 EnumConstantDecl *ECD = 6870 cast_or_null<EnumConstantDecl>(Elements[i]); 6871 if (!ECD) continue; // Already issued a diagnostic. 6872 6873 const llvm::APSInt &InitVal = ECD->getInitVal(); 6874 6875 // Keep track of the size of positive and negative values. 6876 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6877 NumPositiveBits = std::max(NumPositiveBits, 6878 (unsigned)InitVal.getActiveBits()); 6879 else 6880 NumNegativeBits = std::max(NumNegativeBits, 6881 (unsigned)InitVal.getMinSignedBits()); 6882 6883 // Keep track of whether every enum element has type int (very commmon). 6884 if (AllElementsInt) 6885 AllElementsInt = ECD->getType() == Context.IntTy; 6886 } 6887 6888 // Figure out the type that should be used for this enum. 6889 // FIXME: Support -fshort-enums. 6890 QualType BestType; 6891 unsigned BestWidth; 6892 6893 // C++0x N3000 [conv.prom]p3: 6894 // An rvalue of an unscoped enumeration type whose underlying 6895 // type is not fixed can be converted to an rvalue of the first 6896 // of the following types that can represent all the values of 6897 // the enumeration: int, unsigned int, long int, unsigned long 6898 // int, long long int, or unsigned long long int. 6899 // C99 6.4.4.3p2: 6900 // An identifier declared as an enumeration constant has type int. 6901 // The C99 rule is modified by a gcc extension 6902 QualType BestPromotionType; 6903 6904 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6905 6906 if (NumNegativeBits) { 6907 // If there is a negative value, figure out the smallest integer type (of 6908 // int/long/longlong) that fits. 6909 // If it's packed, check also if it fits a char or a short. 6910 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6911 BestType = Context.SignedCharTy; 6912 BestWidth = CharWidth; 6913 } else if (Packed && NumNegativeBits <= ShortWidth && 6914 NumPositiveBits < ShortWidth) { 6915 BestType = Context.ShortTy; 6916 BestWidth = ShortWidth; 6917 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6918 BestType = Context.IntTy; 6919 BestWidth = IntWidth; 6920 } else { 6921 BestWidth = Context.Target.getLongWidth(); 6922 6923 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6924 BestType = Context.LongTy; 6925 } else { 6926 BestWidth = Context.Target.getLongLongWidth(); 6927 6928 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6929 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6930 BestType = Context.LongLongTy; 6931 } 6932 } 6933 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6934 } else { 6935 // If there is no negative value, figure out the smallest type that fits 6936 // all of the enumerator values. 6937 // If it's packed, check also if it fits a char or a short. 6938 if (Packed && NumPositiveBits <= CharWidth) { 6939 BestType = Context.UnsignedCharTy; 6940 BestPromotionType = Context.IntTy; 6941 BestWidth = CharWidth; 6942 } else if (Packed && NumPositiveBits <= ShortWidth) { 6943 BestType = Context.UnsignedShortTy; 6944 BestPromotionType = Context.IntTy; 6945 BestWidth = ShortWidth; 6946 } else if (NumPositiveBits <= IntWidth) { 6947 BestType = Context.UnsignedIntTy; 6948 BestWidth = IntWidth; 6949 BestPromotionType 6950 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6951 ? Context.UnsignedIntTy : Context.IntTy; 6952 } else if (NumPositiveBits <= 6953 (BestWidth = Context.Target.getLongWidth())) { 6954 BestType = Context.UnsignedLongTy; 6955 BestPromotionType 6956 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6957 ? Context.UnsignedLongTy : Context.LongTy; 6958 } else { 6959 BestWidth = Context.Target.getLongLongWidth(); 6960 assert(NumPositiveBits <= BestWidth && 6961 "How could an initializer get larger than ULL?"); 6962 BestType = Context.UnsignedLongLongTy; 6963 BestPromotionType 6964 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6965 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6966 } 6967 } 6968 6969 // Loop over all of the enumerator constants, changing their types to match 6970 // the type of the enum if needed. 6971 for (unsigned i = 0; i != NumElements; ++i) { 6972 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 6973 if (!ECD) continue; // Already issued a diagnostic. 6974 6975 // Standard C says the enumerators have int type, but we allow, as an 6976 // extension, the enumerators to be larger than int size. If each 6977 // enumerator value fits in an int, type it as an int, otherwise type it the 6978 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6979 // that X has type 'int', not 'unsigned'. 6980 6981 // Determine whether the value fits into an int. 6982 llvm::APSInt InitVal = ECD->getInitVal(); 6983 6984 // If it fits into an integer type, force it. Otherwise force it to match 6985 // the enum decl type. 6986 QualType NewTy; 6987 unsigned NewWidth; 6988 bool NewSign; 6989 if (!getLangOptions().CPlusPlus && 6990 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6991 NewTy = Context.IntTy; 6992 NewWidth = IntWidth; 6993 NewSign = true; 6994 } else if (ECD->getType() == BestType) { 6995 // Already the right type! 6996 if (getLangOptions().CPlusPlus) 6997 // C++ [dcl.enum]p4: Following the closing brace of an 6998 // enum-specifier, each enumerator has the type of its 6999 // enumeration. 7000 ECD->setType(EnumType); 7001 continue; 7002 } else { 7003 NewTy = BestType; 7004 NewWidth = BestWidth; 7005 NewSign = BestType->isSignedIntegerType(); 7006 } 7007 7008 // Adjust the APSInt value. 7009 InitVal.extOrTrunc(NewWidth); 7010 InitVal.setIsSigned(NewSign); 7011 ECD->setInitVal(InitVal); 7012 7013 // Adjust the Expr initializer and type. 7014 if (ECD->getInitExpr()) 7015 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 7016 CastExpr::CK_IntegralCast, 7017 ECD->getInitExpr(), 7018 /*base paths*/ 0, 7019 ImplicitCastExpr::RValue)); 7020 if (getLangOptions().CPlusPlus) 7021 // C++ [dcl.enum]p4: Following the closing brace of an 7022 // enum-specifier, each enumerator has the type of its 7023 // enumeration. 7024 ECD->setType(EnumType); 7025 else 7026 ECD->setType(NewTy); 7027 } 7028 7029 Enum->completeDefinition(BestType, BestPromotionType, 7030 NumPositiveBits, NumNegativeBits); 7031} 7032 7033Decl *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, Expr *expr) { 7034 StringLiteral *AsmString = cast<StringLiteral>(expr); 7035 7036 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 7037 Loc, AsmString); 7038 CurContext->addDecl(New); 7039 return New; 7040} 7041 7042void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 7043 SourceLocation PragmaLoc, 7044 SourceLocation NameLoc) { 7045 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 7046 7047 if (PrevDecl) { 7048 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 7049 } else { 7050 (void)WeakUndeclaredIdentifiers.insert( 7051 std::pair<IdentifierInfo*,WeakInfo> 7052 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 7053 } 7054} 7055 7056void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 7057 IdentifierInfo* AliasName, 7058 SourceLocation PragmaLoc, 7059 SourceLocation NameLoc, 7060 SourceLocation AliasNameLoc) { 7061 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 7062 LookupOrdinaryName); 7063 WeakInfo W = WeakInfo(Name, NameLoc); 7064 7065 if (PrevDecl) { 7066 if (!PrevDecl->hasAttr<AliasAttr>()) 7067 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 7068 DeclApplyPragmaWeak(TUScope, ND, W); 7069 } else { 7070 (void)WeakUndeclaredIdentifiers.insert( 7071 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 7072 } 7073} 7074