SemaDecl.cpp revision f9a0a1bf258304428c1f37eb461f01f323b9687a
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/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.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(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, 91 // so build a dependent node to describe the type. 92 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), II, 94 SourceLocation(), SS->getRange(), NameLoc 95 ).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && 102 RequireCompleteDeclContext(*SS, LookupCtx)) 103 return 0; 104 } 105 106 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 107 // lookup for class-names. 108 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 109 LookupOrdinaryName; 110 LookupResult Result(*this, &II, NameLoc, Kind); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::NotFoundInCurrentInstantiation: 136 case LookupResult::FoundOverloaded: 137 case LookupResult::FoundUnresolvedValue: 138 Result.suppressDiagnostics(); 139 return 0; 140 141 case LookupResult::Ambiguous: 142 // Recover from type-hiding ambiguities by hiding the type. We'll 143 // do the lookup again when looking for an object, and we can 144 // diagnose the error then. If we don't do this, then the error 145 // about hiding the type will be immediately followed by an error 146 // that only makes sense if the identifier was treated like a type. 147 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 148 Result.suppressDiagnostics(); 149 return 0; 150 } 151 152 // Look to see if we have a type anywhere in the list of results. 153 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 154 Res != ResEnd; ++Res) { 155 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 156 if (!IIDecl || 157 (*Res)->getLocation().getRawEncoding() < 158 IIDecl->getLocation().getRawEncoding()) 159 IIDecl = *Res; 160 } 161 } 162 163 if (!IIDecl) { 164 // None of the entities we found is a type, so there is no way 165 // to even assume that the result is a type. In this case, don't 166 // complain about the ambiguity. The parser will either try to 167 // perform this lookup again (e.g., as an object name), which 168 // will produce the ambiguity, or will complain that it expected 169 // a type name. 170 Result.suppressDiagnostics(); 171 return 0; 172 } 173 174 // We found a type within the ambiguous lookup; diagnose the 175 // ambiguity and then return that type. This might be the right 176 // answer, or it might not be, but it suppresses any attempt to 177 // perform the name lookup again. 178 break; 179 180 case LookupResult::Found: 181 IIDecl = Result.getFoundDecl(); 182 break; 183 } 184 185 assert(IIDecl && "Didn't find decl"); 186 187 QualType T; 188 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 189 DiagnoseUseOfDecl(IIDecl, NameLoc); 190 191 if (T.isNull()) 192 T = Context.getTypeDeclType(TD); 193 194 if (SS) 195 T = getElaboratedType(ETK_None, *SS, T); 196 197 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 198 T = Context.getObjCInterfaceType(IDecl); 199 } else { 200 // If it's not plausibly a type, suppress diagnostics. 201 Result.suppressDiagnostics(); 202 return 0; 203 } 204 205 return T.getAsOpaquePtr(); 206} 207 208/// isTagName() - This method is called *for error recovery purposes only* 209/// to determine if the specified name is a valid tag name ("struct foo"). If 210/// so, this returns the TST for the tag corresponding to it (TST_enum, 211/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 212/// where the user forgot to specify the tag. 213DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 214 // Do a tag name lookup in this scope. 215 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 216 LookupName(R, S, false); 217 R.suppressDiagnostics(); 218 if (R.getResultKind() == LookupResult::Found) 219 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 220 switch (TD->getTagKind()) { 221 default: return DeclSpec::TST_unspecified; 222 case TTK_Struct: return DeclSpec::TST_struct; 223 case TTK_Union: return DeclSpec::TST_union; 224 case TTK_Class: return DeclSpec::TST_class; 225 case TTK_Enum: return DeclSpec::TST_enum; 226 } 227 } 228 229 return DeclSpec::TST_unspecified; 230} 231 232bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 233 SourceLocation IILoc, 234 Scope *S, 235 CXXScopeSpec *SS, 236 TypeTy *&SuggestedType) { 237 // We don't have anything to suggest (yet). 238 SuggestedType = 0; 239 240 // There may have been a typo in the name of the type. Look up typo 241 // results, in case we have something that we can suggest. 242 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 243 NotForRedeclaration); 244 245 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 246 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 247 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 248 !Result->isInvalidDecl()) { 249 // We found a similarly-named type or interface; suggest that. 250 if (!SS || !SS->isSet()) 251 Diag(IILoc, diag::err_unknown_typename_suggest) 252 << &II << Lookup.getLookupName() 253 << FixItHint::CreateReplacement(SourceRange(IILoc), 254 Result->getNameAsString()); 255 else if (DeclContext *DC = computeDeclContext(*SS, false)) 256 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 257 << &II << DC << Lookup.getLookupName() << SS->getRange() 258 << FixItHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else 261 llvm_unreachable("could not have corrected a typo here"); 262 263 Diag(Result->getLocation(), diag::note_previous_decl) 264 << Result->getDeclName(); 265 266 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 267 return true; 268 } 269 } else if (Lookup.empty()) { 270 // We corrected to a keyword. 271 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Corrected; 274 return true; 275 } 276 } 277 278 if (getLangOptions().CPlusPlus) { 279 // See if II is a class template that the user forgot to pass arguments to. 280 UnqualifiedId Name; 281 Name.setIdentifier(&II, IILoc); 282 CXXScopeSpec EmptySS; 283 TemplateTy TemplateResult; 284 bool MemberOfUnknownSpecialization; 285 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 286 Name, 0, true, TemplateResult, 287 MemberOfUnknownSpecialization) == TNK_Type_template) { 288 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 289 Diag(IILoc, diag::err_template_missing_args) << TplName; 290 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 291 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 292 << TplDecl->getTemplateParameters()->getSourceRange(); 293 } 294 return true; 295 } 296 } 297 298 // FIXME: Should we move the logic that tries to recover from a missing tag 299 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 300 301 if (!SS || (!SS->isSet() && !SS->isInvalid())) 302 Diag(IILoc, diag::err_unknown_typename) << &II; 303 else if (DeclContext *DC = computeDeclContext(*SS, false)) 304 Diag(IILoc, diag::err_typename_nested_not_found) 305 << &II << DC << SS->getRange(); 306 else if (isDependentScopeSpecifier(*SS)) { 307 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 308 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 309 << SourceRange(SS->getRange().getBegin(), IILoc) 310 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 311 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 312 } else { 313 assert(SS && SS->isInvalid() && 314 "Invalid scope specifier has already been diagnosed"); 315 } 316 317 return true; 318} 319 320// Determines the context to return to after temporarily entering a 321// context. This depends in an unnecessarily complicated way on the 322// exact ordering of callbacks from the parser. 323DeclContext *Sema::getContainingDC(DeclContext *DC) { 324 325 // Functions defined inline within classes aren't parsed until we've 326 // finished parsing the top-level class, so the top-level class is 327 // the context we'll need to return to. 328 if (isa<FunctionDecl>(DC)) { 329 DC = DC->getLexicalParent(); 330 331 // A function not defined within a class will always return to its 332 // lexical context. 333 if (!isa<CXXRecordDecl>(DC)) 334 return DC; 335 336 // A C++ inline method/friend is parsed *after* the topmost class 337 // it was declared in is fully parsed ("complete"); the topmost 338 // class is the context we need to return to. 339 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 340 DC = RD; 341 342 // Return the declaration context of the topmost class the inline method is 343 // declared in. 344 return DC; 345 } 346 347 // ObjCMethodDecls are parsed (for some reason) outside the context 348 // of the class. 349 if (isa<ObjCMethodDecl>(DC)) 350 return DC->getLexicalParent()->getLexicalParent(); 351 352 return DC->getLexicalParent(); 353} 354 355void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 356 assert(getContainingDC(DC) == CurContext && 357 "The next DeclContext should be lexically contained in the current one."); 358 CurContext = DC; 359 S->setEntity(DC); 360} 361 362void Sema::PopDeclContext() { 363 assert(CurContext && "DeclContext imbalance!"); 364 365 CurContext = getContainingDC(CurContext); 366 assert(CurContext && "Popped translation unit!"); 367} 368 369/// EnterDeclaratorContext - Used when we must lookup names in the context 370/// of a declarator's nested name specifier. 371/// 372void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 373 // C++0x [basic.lookup.unqual]p13: 374 // A name used in the definition of a static data member of class 375 // X (after the qualified-id of the static member) is looked up as 376 // if the name was used in a member function of X. 377 // C++0x [basic.lookup.unqual]p14: 378 // If a variable member of a namespace is defined outside of the 379 // scope of its namespace then any name used in the definition of 380 // the variable member (after the declarator-id) is looked up as 381 // if the definition of the variable member occurred in its 382 // namespace. 383 // Both of these imply that we should push a scope whose context 384 // is the semantic context of the declaration. We can't use 385 // PushDeclContext here because that context is not necessarily 386 // lexically contained in the current context. Fortunately, 387 // the containing scope should have the appropriate information. 388 389 assert(!S->getEntity() && "scope already has entity"); 390 391#ifndef NDEBUG 392 Scope *Ancestor = S->getParent(); 393 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 394 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 395#endif 396 397 CurContext = DC; 398 S->setEntity(DC); 399} 400 401void Sema::ExitDeclaratorContext(Scope *S) { 402 assert(S->getEntity() == CurContext && "Context imbalance!"); 403 404 // Switch back to the lexical context. The safety of this is 405 // enforced by an assert in EnterDeclaratorContext. 406 Scope *Ancestor = S->getParent(); 407 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 408 CurContext = (DeclContext*) Ancestor->getEntity(); 409 410 // We don't need to do anything with the scope, which is going to 411 // disappear. 412} 413 414/// \brief Determine whether we allow overloading of the function 415/// PrevDecl with another declaration. 416/// 417/// This routine determines whether overloading is possible, not 418/// whether some new function is actually an overload. It will return 419/// true in C++ (where we can always provide overloads) or, as an 420/// extension, in C when the previous function is already an 421/// overloaded function declaration or has the "overloadable" 422/// attribute. 423static bool AllowOverloadingOfFunction(LookupResult &Previous, 424 ASTContext &Context) { 425 if (Context.getLangOptions().CPlusPlus) 426 return true; 427 428 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 429 return true; 430 431 return (Previous.getResultKind() == LookupResult::Found 432 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 433} 434 435/// Add this decl to the scope shadowed decl chains. 436void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 437 // Move up the scope chain until we find the nearest enclosing 438 // non-transparent context. The declaration will be introduced into this 439 // scope. 440 while (S->getEntity() && 441 ((DeclContext *)S->getEntity())->isTransparentContext()) 442 S = S->getParent(); 443 444 // Add scoped declarations into their context, so that they can be 445 // found later. Declarations without a context won't be inserted 446 // into any context. 447 if (AddToContext) 448 CurContext->addDecl(D); 449 450 // Out-of-line definitions shouldn't be pushed into scope in C++. 451 // Out-of-line variable and function definitions shouldn't even in C. 452 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 453 D->isOutOfLine()) 454 return; 455 456 // Template instantiations should also not be pushed into scope. 457 if (isa<FunctionDecl>(D) && 458 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 459 return; 460 461 // If this replaces anything in the current scope, 462 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 463 IEnd = IdResolver.end(); 464 for (; I != IEnd; ++I) { 465 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 466 S->RemoveDecl(DeclPtrTy::make(*I)); 467 IdResolver.RemoveDecl(*I); 468 469 // Should only need to replace one decl. 470 break; 471 } 472 } 473 474 S->AddDecl(DeclPtrTy::make(D)); 475 IdResolver.AddDecl(D); 476} 477 478bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 479 return IdResolver.isDeclInScope(D, Ctx, Context, S); 480} 481 482static bool isOutOfScopePreviousDeclaration(NamedDecl *, 483 DeclContext*, 484 ASTContext&); 485 486/// Filters out lookup results that don't fall within the given scope 487/// as determined by isDeclInScope. 488static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 489 DeclContext *Ctx, Scope *S, 490 bool ConsiderLinkage) { 491 LookupResult::Filter F = R.makeFilter(); 492 while (F.hasNext()) { 493 NamedDecl *D = F.next(); 494 495 if (SemaRef.isDeclInScope(D, Ctx, S)) 496 continue; 497 498 if (ConsiderLinkage && 499 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 500 continue; 501 502 F.erase(); 503 } 504 505 F.done(); 506} 507 508static bool isUsingDecl(NamedDecl *D) { 509 return isa<UsingShadowDecl>(D) || 510 isa<UnresolvedUsingTypenameDecl>(D) || 511 isa<UnresolvedUsingValueDecl>(D); 512} 513 514/// Removes using shadow declarations from the lookup results. 515static void RemoveUsingDecls(LookupResult &R) { 516 LookupResult::Filter F = R.makeFilter(); 517 while (F.hasNext()) 518 if (isUsingDecl(F.next())) 519 F.erase(); 520 521 F.done(); 522} 523 524/// \brief Check for this common pattern: 525/// @code 526/// class S { 527/// S(const S&); // DO NOT IMPLEMENT 528/// void operator=(const S&); // DO NOT IMPLEMENT 529/// }; 530/// @endcode 531static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 532 // FIXME: Should check for private access too but access is set after we get 533 // the decl here. 534 if (D->isThisDeclarationADefinition()) 535 return false; 536 537 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 538 return CD->isCopyConstructor(); 539 return D->isCopyAssignment(); 540} 541 542bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 543 assert(D); 544 545 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 546 return false; 547 548 // Ignore class templates. 549 if (D->getDeclContext()->isDependentContext()) 550 return false; 551 552 // We warn for unused decls internal to the translation unit. 553 if (D->getLinkage() == ExternalLinkage) 554 return false; 555 556 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 557 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 558 return false; 559 560 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 561 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 562 return false; 563 } else { 564 // 'static inline' functions are used in headers; don't warn. 565 if (FD->getStorageClass() == FunctionDecl::Static && 566 FD->isInlineSpecified()) 567 return false; 568 } 569 570 if (FD->isThisDeclarationADefinition()) 571 return !Context.DeclMustBeEmitted(FD); 572 return true; 573 } 574 575 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 576 if (VD->isStaticDataMember() && 577 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 578 return false; 579 580 if ( VD->isFileVarDecl() && 581 !VD->getType().isConstant(Context)) 582 return !Context.DeclMustBeEmitted(VD); 583 } 584 585 return false; 586 } 587 588 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 589 if (!D) 590 return; 591 592 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 593 const FunctionDecl *First = FD->getFirstDeclaration(); 594 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 595 return; // First should already be in the vector. 596 } 597 598 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 599 const VarDecl *First = VD->getFirstDeclaration(); 600 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 601 return; // First should already be in the vector. 602 } 603 604 if (ShouldWarnIfUnusedFileScopedDecl(D)) 605 UnusedFileScopedDecls.push_back(D); 606 } 607 608static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 609 if (D->isInvalidDecl()) 610 return false; 611 612 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 613 return false; 614 615 // White-list anything that isn't a local variable. 616 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 617 !D->getDeclContext()->isFunctionOrMethod()) 618 return false; 619 620 // Types of valid local variables should be complete, so this should succeed. 621 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 622 623 // White-list anything with an __attribute__((unused)) type. 624 QualType Ty = VD->getType(); 625 626 // Only look at the outermost level of typedef. 627 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 628 if (TT->getDecl()->hasAttr<UnusedAttr>()) 629 return false; 630 } 631 632 // If we failed to complete the type for some reason, or if the type is 633 // dependent, don't diagnose the variable. 634 if (Ty->isIncompleteType() || Ty->isDependentType()) 635 return false; 636 637 if (const TagType *TT = Ty->getAs<TagType>()) { 638 const TagDecl *Tag = TT->getDecl(); 639 if (Tag->hasAttr<UnusedAttr>()) 640 return false; 641 642 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 643 // FIXME: Checking for the presence of a user-declared constructor 644 // isn't completely accurate; we'd prefer to check that the initializer 645 // has no side effects. 646 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 647 return false; 648 } 649 } 650 651 // TODO: __attribute__((unused)) templates? 652 } 653 654 return true; 655} 656 657void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 658 if (!ShouldDiagnoseUnusedDecl(D)) 659 return; 660 661 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 662 Diag(D->getLocation(), diag::warn_unused_exception_param) 663 << D->getDeclName(); 664 else 665 Diag(D->getLocation(), diag::warn_unused_variable) 666 << D->getDeclName(); 667} 668 669void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 670 if (S->decl_empty()) return; 671 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 672 "Scope shouldn't contain decls!"); 673 674 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 675 I != E; ++I) { 676 Decl *TmpD = (*I).getAs<Decl>(); 677 assert(TmpD && "This decl didn't get pushed??"); 678 679 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 680 NamedDecl *D = cast<NamedDecl>(TmpD); 681 682 if (!D->getDeclName()) continue; 683 684 // Diagnose unused variables in this scope. 685 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 686 DiagnoseUnusedDecl(D); 687 688 // Remove this name from our lexical scope. 689 IdResolver.RemoveDecl(D); 690 } 691} 692 693/// \brief Look for an Objective-C class in the translation unit. 694/// 695/// \param Id The name of the Objective-C class we're looking for. If 696/// typo-correction fixes this name, the Id will be updated 697/// to the fixed name. 698/// 699/// \param IdLoc The location of the name in the translation unit. 700/// 701/// \param TypoCorrection If true, this routine will attempt typo correction 702/// if there is no class with the given name. 703/// 704/// \returns The declaration of the named Objective-C class, or NULL if the 705/// class could not be found. 706ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 707 SourceLocation IdLoc, 708 bool TypoCorrection) { 709 // The third "scope" argument is 0 since we aren't enabling lazy built-in 710 // creation from this context. 711 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 712 713 if (!IDecl && TypoCorrection) { 714 // Perform typo correction at the given location, but only if we 715 // find an Objective-C class name. 716 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 717 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 718 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 719 Diag(IdLoc, diag::err_undef_interface_suggest) 720 << Id << IDecl->getDeclName() 721 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 722 Diag(IDecl->getLocation(), diag::note_previous_decl) 723 << IDecl->getDeclName(); 724 725 Id = IDecl->getIdentifier(); 726 } 727 } 728 729 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 730} 731 732/// getNonFieldDeclScope - Retrieves the innermost scope, starting 733/// from S, where a non-field would be declared. This routine copes 734/// with the difference between C and C++ scoping rules in structs and 735/// unions. For example, the following code is well-formed in C but 736/// ill-formed in C++: 737/// @code 738/// struct S6 { 739/// enum { BAR } e; 740/// }; 741/// 742/// void test_S6() { 743/// struct S6 a; 744/// a.e = BAR; 745/// } 746/// @endcode 747/// For the declaration of BAR, this routine will return a different 748/// scope. The scope S will be the scope of the unnamed enumeration 749/// within S6. In C++, this routine will return the scope associated 750/// with S6, because the enumeration's scope is a transparent 751/// context but structures can contain non-field names. In C, this 752/// routine will return the translation unit scope, since the 753/// enumeration's scope is a transparent context and structures cannot 754/// contain non-field names. 755Scope *Sema::getNonFieldDeclScope(Scope *S) { 756 while (((S->getFlags() & Scope::DeclScope) == 0) || 757 (S->getEntity() && 758 ((DeclContext *)S->getEntity())->isTransparentContext()) || 759 (S->isClassScope() && !getLangOptions().CPlusPlus)) 760 S = S->getParent(); 761 return S; 762} 763 764void Sema::InitBuiltinVaListType() { 765 if (!Context.getBuiltinVaListType().isNull()) 766 return; 767 768 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 769 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 770 LookupOrdinaryName, ForRedeclaration); 771 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 772 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 773} 774 775/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 776/// file scope. lazily create a decl for it. ForRedeclaration is true 777/// if we're creating this built-in in anticipation of redeclaring the 778/// built-in. 779NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 780 Scope *S, bool ForRedeclaration, 781 SourceLocation Loc) { 782 Builtin::ID BID = (Builtin::ID)bid; 783 784 if (Context.BuiltinInfo.hasVAListUse(BID)) 785 InitBuiltinVaListType(); 786 787 ASTContext::GetBuiltinTypeError Error; 788 QualType R = Context.GetBuiltinType(BID, Error); 789 switch (Error) { 790 case ASTContext::GE_None: 791 // Okay 792 break; 793 794 case ASTContext::GE_Missing_stdio: 795 if (ForRedeclaration) 796 Diag(Loc, diag::err_implicit_decl_requires_stdio) 797 << Context.BuiltinInfo.GetName(BID); 798 return 0; 799 800 case ASTContext::GE_Missing_setjmp: 801 if (ForRedeclaration) 802 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 803 << Context.BuiltinInfo.GetName(BID); 804 return 0; 805 } 806 807 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 808 Diag(Loc, diag::ext_implicit_lib_function_decl) 809 << Context.BuiltinInfo.GetName(BID) 810 << R; 811 if (Context.BuiltinInfo.getHeaderName(BID) && 812 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 813 != Diagnostic::Ignored) 814 Diag(Loc, diag::note_please_include_header) 815 << Context.BuiltinInfo.getHeaderName(BID) 816 << Context.BuiltinInfo.GetName(BID); 817 } 818 819 FunctionDecl *New = FunctionDecl::Create(Context, 820 Context.getTranslationUnitDecl(), 821 Loc, II, R, /*TInfo=*/0, 822 FunctionDecl::Extern, 823 FunctionDecl::None, false, 824 /*hasPrototype=*/true); 825 New->setImplicit(); 826 827 // Create Decl objects for each parameter, adding them to the 828 // FunctionDecl. 829 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 830 llvm::SmallVector<ParmVarDecl*, 16> Params; 831 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 832 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 833 FT->getArgType(i), /*TInfo=*/0, 834 VarDecl::None, VarDecl::None, 0)); 835 New->setParams(Params.data(), Params.size()); 836 } 837 838 AddKnownFunctionAttributes(New); 839 840 // TUScope is the translation-unit scope to insert this function into. 841 // FIXME: This is hideous. We need to teach PushOnScopeChains to 842 // relate Scopes to DeclContexts, and probably eliminate CurContext 843 // entirely, but we're not there yet. 844 DeclContext *SavedContext = CurContext; 845 CurContext = Context.getTranslationUnitDecl(); 846 PushOnScopeChains(New, TUScope); 847 CurContext = SavedContext; 848 return New; 849} 850 851/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 852/// same name and scope as a previous declaration 'Old'. Figure out 853/// how to resolve this situation, merging decls or emitting 854/// diagnostics as appropriate. If there was an error, set New to be invalid. 855/// 856void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 857 // If the new decl is known invalid already, don't bother doing any 858 // merging checks. 859 if (New->isInvalidDecl()) return; 860 861 // Allow multiple definitions for ObjC built-in typedefs. 862 // FIXME: Verify the underlying types are equivalent! 863 if (getLangOptions().ObjC1) { 864 const IdentifierInfo *TypeID = New->getIdentifier(); 865 switch (TypeID->getLength()) { 866 default: break; 867 case 2: 868 if (!TypeID->isStr("id")) 869 break; 870 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 871 // Install the built-in type for 'id', ignoring the current definition. 872 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 873 return; 874 case 5: 875 if (!TypeID->isStr("Class")) 876 break; 877 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 878 // Install the built-in type for 'Class', ignoring the current definition. 879 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 880 return; 881 case 3: 882 if (!TypeID->isStr("SEL")) 883 break; 884 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 885 // Install the built-in type for 'SEL', ignoring the current definition. 886 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 887 return; 888 case 8: 889 if (!TypeID->isStr("Protocol")) 890 break; 891 Context.setObjCProtoType(New->getUnderlyingType()); 892 return; 893 } 894 // Fall through - the typedef name was not a builtin type. 895 } 896 897 // Verify the old decl was also a type. 898 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 899 if (!Old) { 900 Diag(New->getLocation(), diag::err_redefinition_different_kind) 901 << New->getDeclName(); 902 903 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 904 if (OldD->getLocation().isValid()) 905 Diag(OldD->getLocation(), diag::note_previous_definition); 906 907 return New->setInvalidDecl(); 908 } 909 910 // If the old declaration is invalid, just give up here. 911 if (Old->isInvalidDecl()) 912 return New->setInvalidDecl(); 913 914 // Determine the "old" type we'll use for checking and diagnostics. 915 QualType OldType; 916 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 917 OldType = OldTypedef->getUnderlyingType(); 918 else 919 OldType = Context.getTypeDeclType(Old); 920 921 // If the typedef types are not identical, reject them in all languages and 922 // with any extensions enabled. 923 924 if (OldType != New->getUnderlyingType() && 925 Context.getCanonicalType(OldType) != 926 Context.getCanonicalType(New->getUnderlyingType())) { 927 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 928 << New->getUnderlyingType() << OldType; 929 if (Old->getLocation().isValid()) 930 Diag(Old->getLocation(), diag::note_previous_definition); 931 return New->setInvalidDecl(); 932 } 933 934 // The types match. Link up the redeclaration chain if the old 935 // declaration was a typedef. 936 // FIXME: this is a potential source of wierdness if the type 937 // spellings don't match exactly. 938 if (isa<TypedefDecl>(Old)) 939 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 940 941 if (getLangOptions().Microsoft) 942 return; 943 944 if (getLangOptions().CPlusPlus) { 945 // C++ [dcl.typedef]p2: 946 // In a given non-class scope, a typedef specifier can be used to 947 // redefine the name of any type declared in that scope to refer 948 // to the type to which it already refers. 949 if (!isa<CXXRecordDecl>(CurContext)) 950 return; 951 952 // C++0x [dcl.typedef]p4: 953 // In a given class scope, a typedef specifier can be used to redefine 954 // any class-name declared in that scope that is not also a typedef-name 955 // to refer to the type to which it already refers. 956 // 957 // This wording came in via DR424, which was a correction to the 958 // wording in DR56, which accidentally banned code like: 959 // 960 // struct S { 961 // typedef struct A { } A; 962 // }; 963 // 964 // in the C++03 standard. We implement the C++0x semantics, which 965 // allow the above but disallow 966 // 967 // struct S { 968 // typedef int I; 969 // typedef int I; 970 // }; 971 // 972 // since that was the intent of DR56. 973 if (!isa<TypedefDecl >(Old)) 974 return; 975 976 Diag(New->getLocation(), diag::err_redefinition) 977 << New->getDeclName(); 978 Diag(Old->getLocation(), diag::note_previous_definition); 979 return New->setInvalidDecl(); 980 } 981 982 // If we have a redefinition of a typedef in C, emit a warning. This warning 983 // is normally mapped to an error, but can be controlled with 984 // -Wtypedef-redefinition. If either the original or the redefinition is 985 // in a system header, don't emit this for compatibility with GCC. 986 if (getDiagnostics().getSuppressSystemWarnings() && 987 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 988 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 989 return; 990 991 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 992 << New->getDeclName(); 993 Diag(Old->getLocation(), diag::note_previous_definition); 994 return; 995} 996 997/// DeclhasAttr - returns true if decl Declaration already has the target 998/// attribute. 999static bool 1000DeclHasAttr(const Decl *decl, const Attr *target) { 1001 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 1002 if (attr->getKind() == target->getKind()) 1003 return true; 1004 1005 return false; 1006} 1007 1008/// MergeAttributes - append attributes from the Old decl to the New one. 1009static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 1010 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 1011 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 1012 Attr *NewAttr = attr->clone(C); 1013 NewAttr->setInherited(true); 1014 New->addAttr(NewAttr); 1015 } 1016 } 1017} 1018 1019namespace { 1020 1021/// Used in MergeFunctionDecl to keep track of function parameters in 1022/// C. 1023struct GNUCompatibleParamWarning { 1024 ParmVarDecl *OldParm; 1025 ParmVarDecl *NewParm; 1026 QualType PromotedType; 1027}; 1028 1029} 1030 1031/// getSpecialMember - get the special member enum for a method. 1032Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1033 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1034 if (Ctor->isCopyConstructor()) 1035 return Sema::CXXCopyConstructor; 1036 1037 return Sema::CXXConstructor; 1038 } 1039 1040 if (isa<CXXDestructorDecl>(MD)) 1041 return Sema::CXXDestructor; 1042 1043 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 1044 return Sema::CXXCopyAssignment; 1045} 1046 1047/// canRedefineFunction - checks if a function can be redefined. Currently, 1048/// only extern inline functions can be redefined, and even then only in 1049/// GNU89 mode. 1050static bool canRedefineFunction(const FunctionDecl *FD, 1051 const LangOptions& LangOpts) { 1052 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1053 FD->isInlineSpecified() && 1054 FD->getStorageClass() == FunctionDecl::Extern); 1055} 1056 1057/// MergeFunctionDecl - We just parsed a function 'New' from 1058/// declarator D which has the same name and scope as a previous 1059/// declaration 'Old'. Figure out how to resolve this situation, 1060/// merging decls or emitting diagnostics as appropriate. 1061/// 1062/// In C++, New and Old must be declarations that are not 1063/// overloaded. Use IsOverload to determine whether New and Old are 1064/// overloaded, and to select the Old declaration that New should be 1065/// merged with. 1066/// 1067/// Returns true if there was an error, false otherwise. 1068bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1069 // Verify the old decl was also a function. 1070 FunctionDecl *Old = 0; 1071 if (FunctionTemplateDecl *OldFunctionTemplate 1072 = dyn_cast<FunctionTemplateDecl>(OldD)) 1073 Old = OldFunctionTemplate->getTemplatedDecl(); 1074 else 1075 Old = dyn_cast<FunctionDecl>(OldD); 1076 if (!Old) { 1077 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1078 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1079 Diag(Shadow->getTargetDecl()->getLocation(), 1080 diag::note_using_decl_target); 1081 Diag(Shadow->getUsingDecl()->getLocation(), 1082 diag::note_using_decl) << 0; 1083 return true; 1084 } 1085 1086 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1087 << New->getDeclName(); 1088 Diag(OldD->getLocation(), diag::note_previous_definition); 1089 return true; 1090 } 1091 1092 // Determine whether the previous declaration was a definition, 1093 // implicit declaration, or a declaration. 1094 diag::kind PrevDiag; 1095 if (Old->isThisDeclarationADefinition()) 1096 PrevDiag = diag::note_previous_definition; 1097 else if (Old->isImplicit()) 1098 PrevDiag = diag::note_previous_implicit_declaration; 1099 else 1100 PrevDiag = diag::note_previous_declaration; 1101 1102 QualType OldQType = Context.getCanonicalType(Old->getType()); 1103 QualType NewQType = Context.getCanonicalType(New->getType()); 1104 1105 // Don't complain about this if we're in GNU89 mode and the old function 1106 // is an extern inline function. 1107 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1108 New->getStorageClass() == FunctionDecl::Static && 1109 Old->getStorageClass() != FunctionDecl::Static && 1110 !canRedefineFunction(Old, getLangOptions())) { 1111 Diag(New->getLocation(), diag::err_static_non_static) 1112 << New; 1113 Diag(Old->getLocation(), PrevDiag); 1114 return true; 1115 } 1116 1117 // If a function is first declared with a calling convention, but is 1118 // later declared or defined without one, the second decl assumes the 1119 // calling convention of the first. 1120 // 1121 // For the new decl, we have to look at the NON-canonical type to tell the 1122 // difference between a function that really doesn't have a calling 1123 // convention and one that is declared cdecl. That's because in 1124 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1125 // because it is the default calling convention. 1126 // 1127 // Note also that we DO NOT return at this point, because we still have 1128 // other tests to run. 1129 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1130 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1131 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1132 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1133 if (OldTypeInfo.getCC() != CC_Default && 1134 NewTypeInfo.getCC() == CC_Default) { 1135 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1136 New->setType(NewQType); 1137 NewQType = Context.getCanonicalType(NewQType); 1138 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1139 NewTypeInfo.getCC())) { 1140 // Calling conventions really aren't compatible, so complain. 1141 Diag(New->getLocation(), diag::err_cconv_change) 1142 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1143 << (OldTypeInfo.getCC() == CC_Default) 1144 << (OldTypeInfo.getCC() == CC_Default ? "" : 1145 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1146 Diag(Old->getLocation(), diag::note_previous_declaration); 1147 return true; 1148 } 1149 1150 // FIXME: diagnose the other way around? 1151 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1152 NewQType = Context.getNoReturnType(NewQType); 1153 New->setType(NewQType); 1154 assert(NewQType.isCanonical()); 1155 } 1156 1157 // Merge regparm attribute. 1158 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1159 if (NewType->getRegParmType()) { 1160 Diag(New->getLocation(), diag::err_regparm_mismatch) 1161 << NewType->getRegParmType() 1162 << OldType->getRegParmType(); 1163 Diag(Old->getLocation(), diag::note_previous_declaration); 1164 return true; 1165 } 1166 1167 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1168 New->setType(NewQType); 1169 assert(NewQType.isCanonical()); 1170 } 1171 1172 if (getLangOptions().CPlusPlus) { 1173 // (C++98 13.1p2): 1174 // Certain function declarations cannot be overloaded: 1175 // -- Function declarations that differ only in the return type 1176 // cannot be overloaded. 1177 QualType OldReturnType 1178 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1179 QualType NewReturnType 1180 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1181 QualType ResQT; 1182 if (OldReturnType != NewReturnType) { 1183 if (NewReturnType->isObjCObjectPointerType() 1184 && OldReturnType->isObjCObjectPointerType()) 1185 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1186 if (ResQT.isNull()) { 1187 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1188 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1189 return true; 1190 } 1191 else 1192 NewQType = ResQT; 1193 } 1194 1195 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1196 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1197 if (OldMethod && NewMethod) { 1198 // Preserve triviality. 1199 NewMethod->setTrivial(OldMethod->isTrivial()); 1200 1201 bool isFriend = NewMethod->getFriendObjectKind(); 1202 1203 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1204 // -- Member function declarations with the same name and the 1205 // same parameter types cannot be overloaded if any of them 1206 // is a static member function declaration. 1207 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1208 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1209 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1210 return true; 1211 } 1212 1213 // C++ [class.mem]p1: 1214 // [...] A member shall not be declared twice in the 1215 // member-specification, except that a nested class or member 1216 // class template can be declared and then later defined. 1217 unsigned NewDiag; 1218 if (isa<CXXConstructorDecl>(OldMethod)) 1219 NewDiag = diag::err_constructor_redeclared; 1220 else if (isa<CXXDestructorDecl>(NewMethod)) 1221 NewDiag = diag::err_destructor_redeclared; 1222 else if (isa<CXXConversionDecl>(NewMethod)) 1223 NewDiag = diag::err_conv_function_redeclared; 1224 else 1225 NewDiag = diag::err_member_redeclared; 1226 1227 Diag(New->getLocation(), NewDiag); 1228 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1229 1230 // Complain if this is an explicit declaration of a special 1231 // member that was initially declared implicitly. 1232 // 1233 // As an exception, it's okay to befriend such methods in order 1234 // to permit the implicit constructor/destructor/operator calls. 1235 } else if (OldMethod->isImplicit()) { 1236 if (isFriend) { 1237 NewMethod->setImplicit(); 1238 } else { 1239 Diag(NewMethod->getLocation(), 1240 diag::err_definition_of_implicitly_declared_member) 1241 << New << getSpecialMember(OldMethod); 1242 return true; 1243 } 1244 } 1245 } 1246 1247 // (C++98 8.3.5p3): 1248 // All declarations for a function shall agree exactly in both the 1249 // return type and the parameter-type-list. 1250 // attributes should be ignored when comparing. 1251 if (Context.getNoReturnType(OldQType, false) == 1252 Context.getNoReturnType(NewQType, false)) 1253 return MergeCompatibleFunctionDecls(New, Old); 1254 1255 // Fall through for conflicting redeclarations and redefinitions. 1256 } 1257 1258 // C: Function types need to be compatible, not identical. This handles 1259 // duplicate function decls like "void f(int); void f(enum X);" properly. 1260 if (!getLangOptions().CPlusPlus && 1261 Context.typesAreCompatible(OldQType, NewQType)) { 1262 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1263 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1264 const FunctionProtoType *OldProto = 0; 1265 if (isa<FunctionNoProtoType>(NewFuncType) && 1266 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1267 // The old declaration provided a function prototype, but the 1268 // new declaration does not. Merge in the prototype. 1269 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1270 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1271 OldProto->arg_type_end()); 1272 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1273 ParamTypes.data(), ParamTypes.size(), 1274 OldProto->isVariadic(), 1275 OldProto->getTypeQuals(), 1276 false, false, 0, 0, 1277 OldProto->getExtInfo()); 1278 New->setType(NewQType); 1279 New->setHasInheritedPrototype(); 1280 1281 // Synthesize a parameter for each argument type. 1282 llvm::SmallVector<ParmVarDecl*, 16> Params; 1283 for (FunctionProtoType::arg_type_iterator 1284 ParamType = OldProto->arg_type_begin(), 1285 ParamEnd = OldProto->arg_type_end(); 1286 ParamType != ParamEnd; ++ParamType) { 1287 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1288 SourceLocation(), 0, 1289 *ParamType, /*TInfo=*/0, 1290 VarDecl::None, VarDecl::None, 1291 0); 1292 Param->setImplicit(); 1293 Params.push_back(Param); 1294 } 1295 1296 New->setParams(Params.data(), Params.size()); 1297 } 1298 1299 return MergeCompatibleFunctionDecls(New, Old); 1300 } 1301 1302 // GNU C permits a K&R definition to follow a prototype declaration 1303 // if the declared types of the parameters in the K&R definition 1304 // match the types in the prototype declaration, even when the 1305 // promoted types of the parameters from the K&R definition differ 1306 // from the types in the prototype. GCC then keeps the types from 1307 // the prototype. 1308 // 1309 // If a variadic prototype is followed by a non-variadic K&R definition, 1310 // the K&R definition becomes variadic. This is sort of an edge case, but 1311 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1312 // C99 6.9.1p8. 1313 if (!getLangOptions().CPlusPlus && 1314 Old->hasPrototype() && !New->hasPrototype() && 1315 New->getType()->getAs<FunctionProtoType>() && 1316 Old->getNumParams() == New->getNumParams()) { 1317 llvm::SmallVector<QualType, 16> ArgTypes; 1318 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1319 const FunctionProtoType *OldProto 1320 = Old->getType()->getAs<FunctionProtoType>(); 1321 const FunctionProtoType *NewProto 1322 = New->getType()->getAs<FunctionProtoType>(); 1323 1324 // Determine whether this is the GNU C extension. 1325 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1326 NewProto->getResultType()); 1327 bool LooseCompatible = !MergedReturn.isNull(); 1328 for (unsigned Idx = 0, End = Old->getNumParams(); 1329 LooseCompatible && Idx != End; ++Idx) { 1330 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1331 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1332 if (Context.typesAreCompatible(OldParm->getType(), 1333 NewProto->getArgType(Idx))) { 1334 ArgTypes.push_back(NewParm->getType()); 1335 } else if (Context.typesAreCompatible(OldParm->getType(), 1336 NewParm->getType(), 1337 /*CompareUnqualified=*/true)) { 1338 GNUCompatibleParamWarning Warn 1339 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1340 Warnings.push_back(Warn); 1341 ArgTypes.push_back(NewParm->getType()); 1342 } else 1343 LooseCompatible = false; 1344 } 1345 1346 if (LooseCompatible) { 1347 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1348 Diag(Warnings[Warn].NewParm->getLocation(), 1349 diag::ext_param_promoted_not_compatible_with_prototype) 1350 << Warnings[Warn].PromotedType 1351 << Warnings[Warn].OldParm->getType(); 1352 if (Warnings[Warn].OldParm->getLocation().isValid()) 1353 Diag(Warnings[Warn].OldParm->getLocation(), 1354 diag::note_previous_declaration); 1355 } 1356 1357 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1358 ArgTypes.size(), 1359 OldProto->isVariadic(), 0, 1360 false, false, 0, 0, 1361 OldProto->getExtInfo())); 1362 return MergeCompatibleFunctionDecls(New, Old); 1363 } 1364 1365 // Fall through to diagnose conflicting types. 1366 } 1367 1368 // A function that has already been declared has been redeclared or defined 1369 // with a different type- show appropriate diagnostic 1370 if (unsigned BuiltinID = Old->getBuiltinID()) { 1371 // The user has declared a builtin function with an incompatible 1372 // signature. 1373 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1374 // The function the user is redeclaring is a library-defined 1375 // function like 'malloc' or 'printf'. Warn about the 1376 // redeclaration, then pretend that we don't know about this 1377 // library built-in. 1378 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1379 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1380 << Old << Old->getType(); 1381 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1382 Old->setInvalidDecl(); 1383 return false; 1384 } 1385 1386 PrevDiag = diag::note_previous_builtin_declaration; 1387 } 1388 1389 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1390 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1391 return true; 1392} 1393 1394/// \brief Completes the merge of two function declarations that are 1395/// known to be compatible. 1396/// 1397/// This routine handles the merging of attributes and other 1398/// properties of function declarations form the old declaration to 1399/// the new declaration, once we know that New is in fact a 1400/// redeclaration of Old. 1401/// 1402/// \returns false 1403bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1404 // Merge the attributes 1405 MergeAttributes(New, Old, Context); 1406 1407 // Merge the storage class. 1408 if (Old->getStorageClass() != FunctionDecl::Extern && 1409 Old->getStorageClass() != FunctionDecl::None) 1410 New->setStorageClass(Old->getStorageClass()); 1411 1412 // Merge "pure" flag. 1413 if (Old->isPure()) 1414 New->setPure(); 1415 1416 // Merge the "deleted" flag. 1417 if (Old->isDeleted()) 1418 New->setDeleted(); 1419 1420 if (getLangOptions().CPlusPlus) 1421 return MergeCXXFunctionDecl(New, Old); 1422 1423 return false; 1424} 1425 1426/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1427/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1428/// situation, merging decls or emitting diagnostics as appropriate. 1429/// 1430/// Tentative definition rules (C99 6.9.2p2) are checked by 1431/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1432/// definitions here, since the initializer hasn't been attached. 1433/// 1434void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1435 // If the new decl is already invalid, don't do any other checking. 1436 if (New->isInvalidDecl()) 1437 return; 1438 1439 // Verify the old decl was also a variable. 1440 VarDecl *Old = 0; 1441 if (!Previous.isSingleResult() || 1442 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1443 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1444 << New->getDeclName(); 1445 Diag(Previous.getRepresentativeDecl()->getLocation(), 1446 diag::note_previous_definition); 1447 return New->setInvalidDecl(); 1448 } 1449 1450 MergeAttributes(New, Old, Context); 1451 1452 // Merge the types 1453 QualType MergedT; 1454 if (getLangOptions().CPlusPlus) { 1455 if (Context.hasSameType(New->getType(), Old->getType())) 1456 MergedT = New->getType(); 1457 // C++ [basic.link]p10: 1458 // [...] the types specified by all declarations referring to a given 1459 // object or function shall be identical, except that declarations for an 1460 // array object can specify array types that differ by the presence or 1461 // absence of a major array bound (8.3.4). 1462 else if (Old->getType()->isIncompleteArrayType() && 1463 New->getType()->isArrayType()) { 1464 CanQual<ArrayType> OldArray 1465 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1466 CanQual<ArrayType> NewArray 1467 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1468 if (OldArray->getElementType() == NewArray->getElementType()) 1469 MergedT = New->getType(); 1470 } else if (Old->getType()->isArrayType() && 1471 New->getType()->isIncompleteArrayType()) { 1472 CanQual<ArrayType> OldArray 1473 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1474 CanQual<ArrayType> NewArray 1475 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1476 if (OldArray->getElementType() == NewArray->getElementType()) 1477 MergedT = Old->getType(); 1478 } else if (New->getType()->isObjCObjectPointerType() 1479 && Old->getType()->isObjCObjectPointerType()) { 1480 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1481 } 1482 } else { 1483 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1484 } 1485 if (MergedT.isNull()) { 1486 Diag(New->getLocation(), diag::err_redefinition_different_type) 1487 << New->getDeclName(); 1488 Diag(Old->getLocation(), diag::note_previous_definition); 1489 return New->setInvalidDecl(); 1490 } 1491 New->setType(MergedT); 1492 1493 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1494 if (New->getStorageClass() == VarDecl::Static && 1495 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1496 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1497 Diag(Old->getLocation(), diag::note_previous_definition); 1498 return New->setInvalidDecl(); 1499 } 1500 // C99 6.2.2p4: 1501 // For an identifier declared with the storage-class specifier 1502 // extern in a scope in which a prior declaration of that 1503 // identifier is visible,23) if the prior declaration specifies 1504 // internal or external linkage, the linkage of the identifier at 1505 // the later declaration is the same as the linkage specified at 1506 // the prior declaration. If no prior declaration is visible, or 1507 // if the prior declaration specifies no linkage, then the 1508 // identifier has external linkage. 1509 if (New->hasExternalStorage() && Old->hasLinkage()) 1510 /* Okay */; 1511 else if (New->getStorageClass() != VarDecl::Static && 1512 Old->getStorageClass() == VarDecl::Static) { 1513 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1514 Diag(Old->getLocation(), diag::note_previous_definition); 1515 return New->setInvalidDecl(); 1516 } 1517 1518 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1519 1520 // FIXME: The test for external storage here seems wrong? We still 1521 // need to check for mismatches. 1522 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1523 // Don't complain about out-of-line definitions of static members. 1524 !(Old->getLexicalDeclContext()->isRecord() && 1525 !New->getLexicalDeclContext()->isRecord())) { 1526 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1527 Diag(Old->getLocation(), diag::note_previous_definition); 1528 return New->setInvalidDecl(); 1529 } 1530 1531 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1532 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1533 Diag(Old->getLocation(), diag::note_previous_definition); 1534 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1535 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1536 Diag(Old->getLocation(), diag::note_previous_definition); 1537 } 1538 1539 // C++ doesn't have tentative definitions, so go right ahead and check here. 1540 const VarDecl *Def; 1541 if (getLangOptions().CPlusPlus && 1542 New->isThisDeclarationADefinition() == VarDecl::Definition && 1543 (Def = Old->getDefinition())) { 1544 Diag(New->getLocation(), diag::err_redefinition) 1545 << New->getDeclName(); 1546 Diag(Def->getLocation(), diag::note_previous_definition); 1547 New->setInvalidDecl(); 1548 return; 1549 } 1550 // c99 6.2.2 P4. 1551 // For an identifier declared with the storage-class specifier extern in a 1552 // scope in which a prior declaration of that identifier is visible, if 1553 // the prior declaration specifies internal or external linkage, the linkage 1554 // of the identifier at the later declaration is the same as the linkage 1555 // specified at the prior declaration. 1556 // FIXME. revisit this code. 1557 if (New->hasExternalStorage() && 1558 Old->getLinkage() == InternalLinkage && 1559 New->getDeclContext() == Old->getDeclContext()) 1560 New->setStorageClass(Old->getStorageClass()); 1561 1562 // Keep a chain of previous declarations. 1563 New->setPreviousDeclaration(Old); 1564 1565 // Inherit access appropriately. 1566 New->setAccess(Old->getAccess()); 1567} 1568 1569/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1570/// no declarator (e.g. "struct foo;") is parsed. 1571Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1572 DeclSpec &DS) { 1573 // FIXME: Error on auto/register at file scope 1574 // FIXME: Error on inline/virtual/explicit 1575 // FIXME: Warn on useless __thread 1576 // FIXME: Warn on useless const/volatile 1577 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1578 // FIXME: Warn on useless attributes 1579 Decl *TagD = 0; 1580 TagDecl *Tag = 0; 1581 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1582 DS.getTypeSpecType() == DeclSpec::TST_struct || 1583 DS.getTypeSpecType() == DeclSpec::TST_union || 1584 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1585 TagD = static_cast<Decl *>(DS.getTypeRep()); 1586 1587 if (!TagD) // We probably had an error 1588 return DeclPtrTy(); 1589 1590 // Note that the above type specs guarantee that the 1591 // type rep is a Decl, whereas in many of the others 1592 // it's a Type. 1593 Tag = dyn_cast<TagDecl>(TagD); 1594 } 1595 1596 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1597 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1598 // or incomplete types shall not be restrict-qualified." 1599 if (TypeQuals & DeclSpec::TQ_restrict) 1600 Diag(DS.getRestrictSpecLoc(), 1601 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1602 << DS.getSourceRange(); 1603 } 1604 1605 if (DS.isFriendSpecified()) { 1606 // If we're dealing with a class template decl, assume that the 1607 // template routines are handling it. 1608 if (TagD && isa<ClassTemplateDecl>(TagD)) 1609 return DeclPtrTy(); 1610 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1611 } 1612 1613 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1614 // If there are attributes in the DeclSpec, apply them to the record. 1615 if (const AttributeList *AL = DS.getAttributes()) 1616 ProcessDeclAttributeList(S, Record, AL); 1617 1618 if (!Record->getDeclName() && Record->isDefinition() && 1619 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1620 if (getLangOptions().CPlusPlus || 1621 Record->getDeclContext()->isRecord()) 1622 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1623 1624 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1625 << DS.getSourceRange(); 1626 } 1627 1628 // Microsoft allows unnamed struct/union fields. Don't complain 1629 // about them. 1630 // FIXME: Should we support Microsoft's extensions in this area? 1631 if (Record->getDeclName() && getLangOptions().Microsoft) 1632 return DeclPtrTy::make(Tag); 1633 } 1634 1635 if (getLangOptions().CPlusPlus && 1636 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1637 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1638 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1639 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1640 Diag(Enum->getLocation(), diag::ext_no_declarators) 1641 << DS.getSourceRange(); 1642 1643 if (!DS.isMissingDeclaratorOk() && 1644 DS.getTypeSpecType() != DeclSpec::TST_error) { 1645 // Warn about typedefs of enums without names, since this is an 1646 // extension in both Microsoft and GNU. 1647 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1648 Tag && isa<EnumDecl>(Tag)) { 1649 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1650 << DS.getSourceRange(); 1651 return DeclPtrTy::make(Tag); 1652 } 1653 1654 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1655 << DS.getSourceRange(); 1656 } 1657 1658 return DeclPtrTy::make(TagD); 1659} 1660 1661/// We are trying to inject an anonymous member into the given scope; 1662/// check if there's an existing declaration that can't be overloaded. 1663/// 1664/// \return true if this is a forbidden redeclaration 1665static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1666 Scope *S, 1667 DeclContext *Owner, 1668 DeclarationName Name, 1669 SourceLocation NameLoc, 1670 unsigned diagnostic) { 1671 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1672 Sema::ForRedeclaration); 1673 if (!SemaRef.LookupName(R, S)) return false; 1674 1675 if (R.getAsSingle<TagDecl>()) 1676 return false; 1677 1678 // Pick a representative declaration. 1679 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1680 if (PrevDecl && Owner->isRecord()) { 1681 RecordDecl *Record = cast<RecordDecl>(Owner); 1682 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1683 return false; 1684 } 1685 1686 SemaRef.Diag(NameLoc, diagnostic) << Name; 1687 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1688 1689 return true; 1690} 1691 1692/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1693/// anonymous struct or union AnonRecord into the owning context Owner 1694/// and scope S. This routine will be invoked just after we realize 1695/// that an unnamed union or struct is actually an anonymous union or 1696/// struct, e.g., 1697/// 1698/// @code 1699/// union { 1700/// int i; 1701/// float f; 1702/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1703/// // f into the surrounding scope.x 1704/// @endcode 1705/// 1706/// This routine is recursive, injecting the names of nested anonymous 1707/// structs/unions into the owning context and scope as well. 1708static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1709 DeclContext *Owner, 1710 RecordDecl *AnonRecord, 1711 AccessSpecifier AS) { 1712 unsigned diagKind 1713 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1714 : diag::err_anonymous_struct_member_redecl; 1715 1716 bool Invalid = false; 1717 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1718 FEnd = AnonRecord->field_end(); 1719 F != FEnd; ++F) { 1720 if ((*F)->getDeclName()) { 1721 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1722 (*F)->getLocation(), diagKind)) { 1723 // C++ [class.union]p2: 1724 // The names of the members of an anonymous union shall be 1725 // distinct from the names of any other entity in the 1726 // scope in which the anonymous union is declared. 1727 Invalid = true; 1728 } else { 1729 // C++ [class.union]p2: 1730 // For the purpose of name lookup, after the anonymous union 1731 // definition, the members of the anonymous union are 1732 // considered to have been defined in the scope in which the 1733 // anonymous union is declared. 1734 Owner->makeDeclVisibleInContext(*F); 1735 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1736 SemaRef.IdResolver.AddDecl(*F); 1737 1738 // That includes picking up the appropriate access specifier. 1739 if (AS != AS_none) (*F)->setAccess(AS); 1740 } 1741 } else if (const RecordType *InnerRecordType 1742 = (*F)->getType()->getAs<RecordType>()) { 1743 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1744 if (InnerRecord->isAnonymousStructOrUnion()) 1745 Invalid = Invalid || 1746 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1747 InnerRecord, AS); 1748 } 1749 } 1750 1751 return Invalid; 1752} 1753 1754/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1755/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1756/// illegal input values are mapped to VarDecl::None. 1757static VarDecl::StorageClass 1758StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1759 switch (StorageClassSpec) { 1760 case DeclSpec::SCS_unspecified: return VarDecl::None; 1761 case DeclSpec::SCS_extern: return VarDecl::Extern; 1762 case DeclSpec::SCS_static: return VarDecl::Static; 1763 case DeclSpec::SCS_auto: return VarDecl::Auto; 1764 case DeclSpec::SCS_register: return VarDecl::Register; 1765 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1766 // Illegal SCSs map to None: error reporting is up to the caller. 1767 case DeclSpec::SCS_mutable: // Fall through. 1768 case DeclSpec::SCS_typedef: return VarDecl::None; 1769 } 1770 llvm_unreachable("unknown storage class specifier"); 1771} 1772 1773/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1774/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1775/// illegal input values are mapped to FunctionDecl::None. 1776static FunctionDecl::StorageClass 1777StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1778 switch (StorageClassSpec) { 1779 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1780 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1781 case DeclSpec::SCS_static: return FunctionDecl::Static; 1782 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1783 // Illegal SCSs map to None: error reporting is up to the caller. 1784 case DeclSpec::SCS_auto: // Fall through. 1785 case DeclSpec::SCS_mutable: // Fall through. 1786 case DeclSpec::SCS_register: // Fall through. 1787 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1788 } 1789 llvm_unreachable("unknown storage class specifier"); 1790} 1791 1792/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1793/// anonymous structure or union. Anonymous unions are a C++ feature 1794/// (C++ [class.union]) and a GNU C extension; anonymous structures 1795/// are a GNU C and GNU C++ extension. 1796Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1797 AccessSpecifier AS, 1798 RecordDecl *Record) { 1799 DeclContext *Owner = Record->getDeclContext(); 1800 1801 // Diagnose whether this anonymous struct/union is an extension. 1802 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1803 Diag(Record->getLocation(), diag::ext_anonymous_union); 1804 else if (!Record->isUnion()) 1805 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1806 1807 // C and C++ require different kinds of checks for anonymous 1808 // structs/unions. 1809 bool Invalid = false; 1810 if (getLangOptions().CPlusPlus) { 1811 const char* PrevSpec = 0; 1812 unsigned DiagID; 1813 // C++ [class.union]p3: 1814 // Anonymous unions declared in a named namespace or in the 1815 // global namespace shall be declared static. 1816 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1817 (isa<TranslationUnitDecl>(Owner) || 1818 (isa<NamespaceDecl>(Owner) && 1819 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1820 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1821 Invalid = true; 1822 1823 // Recover by adding 'static'. 1824 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1825 PrevSpec, DiagID); 1826 } 1827 // C++ [class.union]p3: 1828 // A storage class is not allowed in a declaration of an 1829 // anonymous union in a class scope. 1830 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1831 isa<RecordDecl>(Owner)) { 1832 Diag(DS.getStorageClassSpecLoc(), 1833 diag::err_anonymous_union_with_storage_spec); 1834 Invalid = true; 1835 1836 // Recover by removing the storage specifier. 1837 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1838 PrevSpec, DiagID); 1839 } 1840 1841 // C++ [class.union]p2: 1842 // The member-specification of an anonymous union shall only 1843 // define non-static data members. [Note: nested types and 1844 // functions cannot be declared within an anonymous union. ] 1845 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1846 MemEnd = Record->decls_end(); 1847 Mem != MemEnd; ++Mem) { 1848 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1849 // C++ [class.union]p3: 1850 // An anonymous union shall not have private or protected 1851 // members (clause 11). 1852 assert(FD->getAccess() != AS_none); 1853 if (FD->getAccess() != AS_public) { 1854 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1855 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1856 Invalid = true; 1857 } 1858 } else if ((*Mem)->isImplicit()) { 1859 // Any implicit members are fine. 1860 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1861 // This is a type that showed up in an 1862 // elaborated-type-specifier inside the anonymous struct or 1863 // union, but which actually declares a type outside of the 1864 // anonymous struct or union. It's okay. 1865 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1866 if (!MemRecord->isAnonymousStructOrUnion() && 1867 MemRecord->getDeclName()) { 1868 // This is a nested type declaration. 1869 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1870 << (int)Record->isUnion(); 1871 Invalid = true; 1872 } 1873 } else if (isa<AccessSpecDecl>(*Mem)) { 1874 // Any access specifier is fine. 1875 } else { 1876 // We have something that isn't a non-static data 1877 // member. Complain about it. 1878 unsigned DK = diag::err_anonymous_record_bad_member; 1879 if (isa<TypeDecl>(*Mem)) 1880 DK = diag::err_anonymous_record_with_type; 1881 else if (isa<FunctionDecl>(*Mem)) 1882 DK = diag::err_anonymous_record_with_function; 1883 else if (isa<VarDecl>(*Mem)) 1884 DK = diag::err_anonymous_record_with_static; 1885 Diag((*Mem)->getLocation(), DK) 1886 << (int)Record->isUnion(); 1887 Invalid = true; 1888 } 1889 } 1890 } 1891 1892 if (!Record->isUnion() && !Owner->isRecord()) { 1893 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1894 << (int)getLangOptions().CPlusPlus; 1895 Invalid = true; 1896 } 1897 1898 // Mock up a declarator. 1899 Declarator Dc(DS, Declarator::TypeNameContext); 1900 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1901 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1902 1903 // Create a declaration for this anonymous struct/union. 1904 NamedDecl *Anon = 0; 1905 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1906 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1907 /*IdentifierInfo=*/0, 1908 Context.getTypeDeclType(Record), 1909 TInfo, 1910 /*BitWidth=*/0, /*Mutable=*/false); 1911 Anon->setAccess(AS); 1912 if (getLangOptions().CPlusPlus) { 1913 FieldCollector->Add(cast<FieldDecl>(Anon)); 1914 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1915 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1916 } 1917 } else { 1918 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1919 assert(SCSpec != DeclSpec::SCS_typedef && 1920 "Parser allowed 'typedef' as storage class VarDecl."); 1921 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1922 if (SCSpec == DeclSpec::SCS_mutable) { 1923 // mutable can only appear on non-static class members, so it's always 1924 // an error here 1925 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1926 Invalid = true; 1927 SC = VarDecl::None; 1928 } 1929 SCSpec = DS.getStorageClassSpecAsWritten(); 1930 VarDecl::StorageClass SCAsWritten 1931 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1932 1933 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1934 /*IdentifierInfo=*/0, 1935 Context.getTypeDeclType(Record), 1936 TInfo, SC, SCAsWritten); 1937 } 1938 Anon->setImplicit(); 1939 1940 // Add the anonymous struct/union object to the current 1941 // context. We'll be referencing this object when we refer to one of 1942 // its members. 1943 Owner->addDecl(Anon); 1944 1945 // Inject the members of the anonymous struct/union into the owning 1946 // context and into the identifier resolver chain for name lookup 1947 // purposes. 1948 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1949 Invalid = true; 1950 1951 // Mark this as an anonymous struct/union type. Note that we do not 1952 // do this until after we have already checked and injected the 1953 // members of this anonymous struct/union type, because otherwise 1954 // the members could be injected twice: once by DeclContext when it 1955 // builds its lookup table, and once by 1956 // InjectAnonymousStructOrUnionMembers. 1957 Record->setAnonymousStructOrUnion(true); 1958 1959 if (Invalid) 1960 Anon->setInvalidDecl(); 1961 1962 return DeclPtrTy::make(Anon); 1963} 1964 1965 1966/// GetNameForDeclarator - Determine the full declaration name for the 1967/// given Declarator. 1968DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 1969 return GetNameFromUnqualifiedId(D.getName()); 1970} 1971 1972/// \brief Retrieves the declaration name from a parsed unqualified-id. 1973DeclarationNameInfo 1974Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1975 DeclarationNameInfo NameInfo; 1976 NameInfo.setLoc(Name.StartLocation); 1977 1978 switch (Name.getKind()) { 1979 1980 case UnqualifiedId::IK_Identifier: 1981 NameInfo.setName(Name.Identifier); 1982 NameInfo.setLoc(Name.StartLocation); 1983 return NameInfo; 1984 1985 case UnqualifiedId::IK_OperatorFunctionId: 1986 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 1987 Name.OperatorFunctionId.Operator)); 1988 NameInfo.setLoc(Name.StartLocation); 1989 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 1990 = Name.OperatorFunctionId.SymbolLocations[0]; 1991 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 1992 = Name.EndLocation.getRawEncoding(); 1993 return NameInfo; 1994 1995 case UnqualifiedId::IK_LiteralOperatorId: 1996 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 1997 Name.Identifier)); 1998 NameInfo.setLoc(Name.StartLocation); 1999 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2000 return NameInfo; 2001 2002 case UnqualifiedId::IK_ConversionFunctionId: { 2003 TypeSourceInfo *TInfo; 2004 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2005 if (Ty.isNull()) 2006 return DeclarationNameInfo(); 2007 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2008 Context.getCanonicalType(Ty))); 2009 NameInfo.setLoc(Name.StartLocation); 2010 NameInfo.setNamedTypeInfo(TInfo); 2011 return NameInfo; 2012 } 2013 2014 case UnqualifiedId::IK_ConstructorName: { 2015 TypeSourceInfo *TInfo; 2016 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2017 if (Ty.isNull()) 2018 return DeclarationNameInfo(); 2019 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2020 Context.getCanonicalType(Ty))); 2021 NameInfo.setLoc(Name.StartLocation); 2022 NameInfo.setNamedTypeInfo(TInfo); 2023 return NameInfo; 2024 } 2025 2026 case UnqualifiedId::IK_ConstructorTemplateId: { 2027 // In well-formed code, we can only have a constructor 2028 // template-id that refers to the current context, so go there 2029 // to find the actual type being constructed. 2030 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2031 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2032 return DeclarationNameInfo(); 2033 2034 // Determine the type of the class being constructed. 2035 QualType CurClassType = Context.getTypeDeclType(CurClass); 2036 2037 // FIXME: Check two things: that the template-id names the same type as 2038 // CurClassType, and that the template-id does not occur when the name 2039 // was qualified. 2040 2041 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2042 Context.getCanonicalType(CurClassType))); 2043 NameInfo.setLoc(Name.StartLocation); 2044 // FIXME: should we retrieve TypeSourceInfo? 2045 NameInfo.setNamedTypeInfo(0); 2046 return NameInfo; 2047 } 2048 2049 case UnqualifiedId::IK_DestructorName: { 2050 TypeSourceInfo *TInfo; 2051 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2052 if (Ty.isNull()) 2053 return DeclarationNameInfo(); 2054 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2055 Context.getCanonicalType(Ty))); 2056 NameInfo.setLoc(Name.StartLocation); 2057 NameInfo.setNamedTypeInfo(TInfo); 2058 return NameInfo; 2059 } 2060 2061 case UnqualifiedId::IK_TemplateId: { 2062 TemplateName TName 2063 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2064 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2065 return Context.getNameForTemplate(TName, TNameLoc); 2066 } 2067 2068 } // switch (Name.getKind()) 2069 2070 assert(false && "Unknown name kind"); 2071 return DeclarationNameInfo(); 2072} 2073 2074/// isNearlyMatchingFunction - Determine whether the C++ functions 2075/// Declaration and Definition are "nearly" matching. This heuristic 2076/// is used to improve diagnostics in the case where an out-of-line 2077/// function definition doesn't match any declaration within 2078/// the class or namespace. 2079static bool isNearlyMatchingFunction(ASTContext &Context, 2080 FunctionDecl *Declaration, 2081 FunctionDecl *Definition) { 2082 if (Declaration->param_size() != Definition->param_size()) 2083 return false; 2084 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2085 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2086 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2087 2088 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2089 DefParamTy.getNonReferenceType())) 2090 return false; 2091 } 2092 2093 return true; 2094} 2095 2096/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2097/// declarator needs to be rebuilt in the current instantiation. 2098/// Any bits of declarator which appear before the name are valid for 2099/// consideration here. That's specifically the type in the decl spec 2100/// and the base type in any member-pointer chunks. 2101static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2102 DeclarationName Name) { 2103 // The types we specifically need to rebuild are: 2104 // - typenames, typeofs, and decltypes 2105 // - types which will become injected class names 2106 // Of course, we also need to rebuild any type referencing such a 2107 // type. It's safest to just say "dependent", but we call out a 2108 // few cases here. 2109 2110 DeclSpec &DS = D.getMutableDeclSpec(); 2111 switch (DS.getTypeSpecType()) { 2112 case DeclSpec::TST_typename: 2113 case DeclSpec::TST_typeofType: 2114 case DeclSpec::TST_typeofExpr: 2115 case DeclSpec::TST_decltype: { 2116 // Grab the type from the parser. 2117 TypeSourceInfo *TSI = 0; 2118 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2119 if (T.isNull() || !T->isDependentType()) break; 2120 2121 // Make sure there's a type source info. This isn't really much 2122 // of a waste; most dependent types should have type source info 2123 // attached already. 2124 if (!TSI) 2125 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2126 2127 // Rebuild the type in the current instantiation. 2128 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2129 if (!TSI) return true; 2130 2131 // Store the new type back in the decl spec. 2132 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2133 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2134 break; 2135 } 2136 2137 default: 2138 // Nothing to do for these decl specs. 2139 break; 2140 } 2141 2142 // It doesn't matter what order we do this in. 2143 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2144 DeclaratorChunk &Chunk = D.getTypeObject(I); 2145 2146 // The only type information in the declarator which can come 2147 // before the declaration name is the base type of a member 2148 // pointer. 2149 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2150 continue; 2151 2152 // Rebuild the scope specifier in-place. 2153 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2154 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2155 return true; 2156 } 2157 2158 return false; 2159} 2160 2161Sema::DeclPtrTy 2162Sema::HandleDeclarator(Scope *S, Declarator &D, 2163 MultiTemplateParamsArg TemplateParamLists, 2164 bool IsFunctionDefinition) { 2165 // TODO: consider using NameInfo for diagnostic. 2166 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2167 DeclarationName Name = NameInfo.getName(); 2168 2169 // All of these full declarators require an identifier. If it doesn't have 2170 // one, the ParsedFreeStandingDeclSpec action should be used. 2171 if (!Name) { 2172 if (!D.isInvalidType()) // Reject this if we think it is valid. 2173 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2174 diag::err_declarator_need_ident) 2175 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2176 return DeclPtrTy(); 2177 } 2178 2179 // The scope passed in may not be a decl scope. Zip up the scope tree until 2180 // we find one that is. 2181 while ((S->getFlags() & Scope::DeclScope) == 0 || 2182 (S->getFlags() & Scope::TemplateParamScope) != 0) 2183 S = S->getParent(); 2184 2185 DeclContext *DC = CurContext; 2186 if (D.getCXXScopeSpec().isInvalid()) 2187 D.setInvalidType(); 2188 else if (D.getCXXScopeSpec().isSet()) { 2189 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2190 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2191 if (!DC) { 2192 // If we could not compute the declaration context, it's because the 2193 // declaration context is dependent but does not refer to a class, 2194 // class template, or class template partial specialization. Complain 2195 // and return early, to avoid the coming semantic disaster. 2196 Diag(D.getIdentifierLoc(), 2197 diag::err_template_qualified_declarator_no_match) 2198 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2199 << D.getCXXScopeSpec().getRange(); 2200 return DeclPtrTy(); 2201 } 2202 2203 bool IsDependentContext = DC->isDependentContext(); 2204 2205 if (!IsDependentContext && 2206 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2207 return DeclPtrTy(); 2208 2209 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2210 Diag(D.getIdentifierLoc(), 2211 diag::err_member_def_undefined_record) 2212 << Name << DC << D.getCXXScopeSpec().getRange(); 2213 D.setInvalidType(); 2214 } 2215 2216 // Check whether we need to rebuild the type of the given 2217 // declaration in the current instantiation. 2218 if (EnteringContext && IsDependentContext && 2219 TemplateParamLists.size() != 0) { 2220 ContextRAII SavedContext(*this, DC); 2221 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2222 D.setInvalidType(); 2223 } 2224 } 2225 2226 NamedDecl *New; 2227 2228 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2229 QualType R = TInfo->getType(); 2230 2231 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2232 ForRedeclaration); 2233 2234 // See if this is a redefinition of a variable in the same scope. 2235 if (!D.getCXXScopeSpec().isSet()) { 2236 bool IsLinkageLookup = false; 2237 2238 // If the declaration we're planning to build will be a function 2239 // or object with linkage, then look for another declaration with 2240 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2241 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2242 /* Do nothing*/; 2243 else if (R->isFunctionType()) { 2244 if (CurContext->isFunctionOrMethod() || 2245 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2246 IsLinkageLookup = true; 2247 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2248 IsLinkageLookup = true; 2249 else if (CurContext->getLookupContext()->isTranslationUnit() && 2250 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2251 IsLinkageLookup = true; 2252 2253 if (IsLinkageLookup) 2254 Previous.clear(LookupRedeclarationWithLinkage); 2255 2256 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2257 } else { // Something like "int foo::x;" 2258 LookupQualifiedName(Previous, DC); 2259 2260 // Don't consider using declarations as previous declarations for 2261 // out-of-line members. 2262 RemoveUsingDecls(Previous); 2263 2264 // C++ 7.3.1.2p2: 2265 // Members (including explicit specializations of templates) of a named 2266 // namespace can also be defined outside that namespace by explicit 2267 // qualification of the name being defined, provided that the entity being 2268 // defined was already declared in the namespace and the definition appears 2269 // after the point of declaration in a namespace that encloses the 2270 // declarations namespace. 2271 // 2272 // Note that we only check the context at this point. We don't yet 2273 // have enough information to make sure that PrevDecl is actually 2274 // the declaration we want to match. For example, given: 2275 // 2276 // class X { 2277 // void f(); 2278 // void f(float); 2279 // }; 2280 // 2281 // void X::f(int) { } // ill-formed 2282 // 2283 // In this case, PrevDecl will point to the overload set 2284 // containing the two f's declared in X, but neither of them 2285 // matches. 2286 2287 // First check whether we named the global scope. 2288 if (isa<TranslationUnitDecl>(DC)) { 2289 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2290 << Name << D.getCXXScopeSpec().getRange(); 2291 } else { 2292 DeclContext *Cur = CurContext; 2293 while (isa<LinkageSpecDecl>(Cur)) 2294 Cur = Cur->getParent(); 2295 if (!Cur->Encloses(DC)) { 2296 // The qualifying scope doesn't enclose the original declaration. 2297 // Emit diagnostic based on current scope. 2298 SourceLocation L = D.getIdentifierLoc(); 2299 SourceRange R = D.getCXXScopeSpec().getRange(); 2300 if (isa<FunctionDecl>(Cur)) 2301 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2302 else 2303 Diag(L, diag::err_invalid_declarator_scope) 2304 << Name << cast<NamedDecl>(DC) << R; 2305 D.setInvalidType(); 2306 } 2307 } 2308 } 2309 2310 if (Previous.isSingleResult() && 2311 Previous.getFoundDecl()->isTemplateParameter()) { 2312 // Maybe we will complain about the shadowed template parameter. 2313 if (!D.isInvalidType()) 2314 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2315 Previous.getFoundDecl())) 2316 D.setInvalidType(); 2317 2318 // Just pretend that we didn't see the previous declaration. 2319 Previous.clear(); 2320 } 2321 2322 // In C++, the previous declaration we find might be a tag type 2323 // (class or enum). In this case, the new declaration will hide the 2324 // tag type. Note that this does does not apply if we're declaring a 2325 // typedef (C++ [dcl.typedef]p4). 2326 if (Previous.isSingleTagDecl() && 2327 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2328 Previous.clear(); 2329 2330 bool Redeclaration = false; 2331 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2332 if (TemplateParamLists.size()) { 2333 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2334 return DeclPtrTy(); 2335 } 2336 2337 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2338 } else if (R->isFunctionType()) { 2339 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2340 move(TemplateParamLists), 2341 IsFunctionDefinition, Redeclaration); 2342 } else { 2343 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2344 move(TemplateParamLists), 2345 Redeclaration); 2346 } 2347 2348 if (New == 0) 2349 return DeclPtrTy(); 2350 2351 // If this has an identifier and is not an invalid redeclaration or 2352 // function template specialization, add it to the scope stack. 2353 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2354 PushOnScopeChains(New, S); 2355 2356 return DeclPtrTy::make(New); 2357} 2358 2359/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2360/// types into constant array types in certain situations which would otherwise 2361/// be errors (for GCC compatibility). 2362static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2363 ASTContext &Context, 2364 bool &SizeIsNegative) { 2365 // This method tries to turn a variable array into a constant 2366 // array even when the size isn't an ICE. This is necessary 2367 // for compatibility with code that depends on gcc's buggy 2368 // constant expression folding, like struct {char x[(int)(char*)2];} 2369 SizeIsNegative = false; 2370 2371 QualifierCollector Qs; 2372 const Type *Ty = Qs.strip(T); 2373 2374 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2375 QualType Pointee = PTy->getPointeeType(); 2376 QualType FixedType = 2377 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2378 if (FixedType.isNull()) return FixedType; 2379 FixedType = Context.getPointerType(FixedType); 2380 return Qs.apply(FixedType); 2381 } 2382 2383 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2384 if (!VLATy) 2385 return QualType(); 2386 // FIXME: We should probably handle this case 2387 if (VLATy->getElementType()->isVariablyModifiedType()) 2388 return QualType(); 2389 2390 Expr::EvalResult EvalResult; 2391 if (!VLATy->getSizeExpr() || 2392 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2393 !EvalResult.Val.isInt()) 2394 return QualType(); 2395 2396 llvm::APSInt &Res = EvalResult.Val.getInt(); 2397 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2398 // TODO: preserve the size expression in declarator info 2399 return Context.getConstantArrayType(VLATy->getElementType(), 2400 Res, ArrayType::Normal, 0); 2401 } 2402 2403 SizeIsNegative = true; 2404 return QualType(); 2405} 2406 2407/// \brief Register the given locally-scoped external C declaration so 2408/// that it can be found later for redeclarations 2409void 2410Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2411 const LookupResult &Previous, 2412 Scope *S) { 2413 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2414 "Decl is not a locally-scoped decl!"); 2415 // Note that we have a locally-scoped external with this name. 2416 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2417 2418 if (!Previous.isSingleResult()) 2419 return; 2420 2421 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2422 2423 // If there was a previous declaration of this variable, it may be 2424 // in our identifier chain. Update the identifier chain with the new 2425 // declaration. 2426 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2427 // The previous declaration was found on the identifer resolver 2428 // chain, so remove it from its scope. 2429 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2430 S = S->getParent(); 2431 2432 if (S) 2433 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2434 } 2435} 2436 2437/// \brief Diagnose function specifiers on a declaration of an identifier that 2438/// does not identify a function. 2439void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2440 // FIXME: We should probably indicate the identifier in question to avoid 2441 // confusion for constructs like "inline int a(), b;" 2442 if (D.getDeclSpec().isInlineSpecified()) 2443 Diag(D.getDeclSpec().getInlineSpecLoc(), 2444 diag::err_inline_non_function); 2445 2446 if (D.getDeclSpec().isVirtualSpecified()) 2447 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2448 diag::err_virtual_non_function); 2449 2450 if (D.getDeclSpec().isExplicitSpecified()) 2451 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2452 diag::err_explicit_non_function); 2453} 2454 2455NamedDecl* 2456Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2457 QualType R, TypeSourceInfo *TInfo, 2458 LookupResult &Previous, bool &Redeclaration) { 2459 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2460 if (D.getCXXScopeSpec().isSet()) { 2461 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2462 << D.getCXXScopeSpec().getRange(); 2463 D.setInvalidType(); 2464 // Pretend we didn't see the scope specifier. 2465 DC = CurContext; 2466 Previous.clear(); 2467 } 2468 2469 if (getLangOptions().CPlusPlus) { 2470 // Check that there are no default arguments (C++ only). 2471 CheckExtraCXXDefaultArguments(D); 2472 } 2473 2474 DiagnoseFunctionSpecifiers(D); 2475 2476 if (D.getDeclSpec().isThreadSpecified()) 2477 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2478 2479 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2480 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2481 << D.getName().getSourceRange(); 2482 return 0; 2483 } 2484 2485 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2486 if (!NewTD) return 0; 2487 2488 // Handle attributes prior to checking for duplicates in MergeVarDecl 2489 ProcessDeclAttributes(S, NewTD, D); 2490 2491 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2492 // then it shall have block scope. 2493 // Note that variably modified types must be fixed before merging the decl so 2494 // that redeclarations will match. 2495 QualType T = NewTD->getUnderlyingType(); 2496 if (T->isVariablyModifiedType()) { 2497 setFunctionHasBranchProtectedScope(); 2498 2499 if (S->getFnParent() == 0) { 2500 bool SizeIsNegative; 2501 QualType FixedTy = 2502 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2503 if (!FixedTy.isNull()) { 2504 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2505 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2506 } else { 2507 if (SizeIsNegative) 2508 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2509 else if (T->isVariableArrayType()) 2510 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2511 else 2512 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2513 NewTD->setInvalidDecl(); 2514 } 2515 } 2516 } 2517 2518 // Merge the decl with the existing one if appropriate. If the decl is 2519 // in an outer scope, it isn't the same thing. 2520 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2521 if (!Previous.empty()) { 2522 Redeclaration = true; 2523 MergeTypeDefDecl(NewTD, Previous); 2524 } 2525 2526 // If this is the C FILE type, notify the AST context. 2527 if (IdentifierInfo *II = NewTD->getIdentifier()) 2528 if (!NewTD->isInvalidDecl() && 2529 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2530 if (II->isStr("FILE")) 2531 Context.setFILEDecl(NewTD); 2532 else if (II->isStr("jmp_buf")) 2533 Context.setjmp_bufDecl(NewTD); 2534 else if (II->isStr("sigjmp_buf")) 2535 Context.setsigjmp_bufDecl(NewTD); 2536 } 2537 2538 return NewTD; 2539} 2540 2541/// \brief Determines whether the given declaration is an out-of-scope 2542/// previous declaration. 2543/// 2544/// This routine should be invoked when name lookup has found a 2545/// previous declaration (PrevDecl) that is not in the scope where a 2546/// new declaration by the same name is being introduced. If the new 2547/// declaration occurs in a local scope, previous declarations with 2548/// linkage may still be considered previous declarations (C99 2549/// 6.2.2p4-5, C++ [basic.link]p6). 2550/// 2551/// \param PrevDecl the previous declaration found by name 2552/// lookup 2553/// 2554/// \param DC the context in which the new declaration is being 2555/// declared. 2556/// 2557/// \returns true if PrevDecl is an out-of-scope previous declaration 2558/// for a new delcaration with the same name. 2559static bool 2560isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2561 ASTContext &Context) { 2562 if (!PrevDecl) 2563 return 0; 2564 2565 if (!PrevDecl->hasLinkage()) 2566 return false; 2567 2568 if (Context.getLangOptions().CPlusPlus) { 2569 // C++ [basic.link]p6: 2570 // If there is a visible declaration of an entity with linkage 2571 // having the same name and type, ignoring entities declared 2572 // outside the innermost enclosing namespace scope, the block 2573 // scope declaration declares that same entity and receives the 2574 // linkage of the previous declaration. 2575 DeclContext *OuterContext = DC->getLookupContext(); 2576 if (!OuterContext->isFunctionOrMethod()) 2577 // This rule only applies to block-scope declarations. 2578 return false; 2579 else { 2580 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2581 if (PrevOuterContext->isRecord()) 2582 // We found a member function: ignore it. 2583 return false; 2584 else { 2585 // Find the innermost enclosing namespace for the new and 2586 // previous declarations. 2587 while (!OuterContext->isFileContext()) 2588 OuterContext = OuterContext->getParent(); 2589 while (!PrevOuterContext->isFileContext()) 2590 PrevOuterContext = PrevOuterContext->getParent(); 2591 2592 // The previous declaration is in a different namespace, so it 2593 // isn't the same function. 2594 if (OuterContext->getPrimaryContext() != 2595 PrevOuterContext->getPrimaryContext()) 2596 return false; 2597 } 2598 } 2599 } 2600 2601 return true; 2602} 2603 2604static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2605 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2606 if (!SS.isSet()) return; 2607 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2608 SS.getRange()); 2609} 2610 2611NamedDecl* 2612Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2613 QualType R, TypeSourceInfo *TInfo, 2614 LookupResult &Previous, 2615 MultiTemplateParamsArg TemplateParamLists, 2616 bool &Redeclaration) { 2617 DeclarationName Name = GetNameForDeclarator(D).getName(); 2618 2619 // Check that there are no default arguments (C++ only). 2620 if (getLangOptions().CPlusPlus) 2621 CheckExtraCXXDefaultArguments(D); 2622 2623 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2624 assert(SCSpec != DeclSpec::SCS_typedef && 2625 "Parser allowed 'typedef' as storage class VarDecl."); 2626 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2627 if (SCSpec == DeclSpec::SCS_mutable) { 2628 // mutable can only appear on non-static class members, so it's always 2629 // an error here 2630 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2631 D.setInvalidType(); 2632 SC = VarDecl::None; 2633 } 2634 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2635 VarDecl::StorageClass SCAsWritten 2636 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2637 2638 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2639 if (!II) { 2640 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2641 << Name.getAsString(); 2642 return 0; 2643 } 2644 2645 DiagnoseFunctionSpecifiers(D); 2646 2647 if (!DC->isRecord() && S->getFnParent() == 0) { 2648 // C99 6.9p2: The storage-class specifiers auto and register shall not 2649 // appear in the declaration specifiers in an external declaration. 2650 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2651 2652 // If this is a register variable with an asm label specified, then this 2653 // is a GNU extension. 2654 if (SC == VarDecl::Register && D.getAsmLabel()) 2655 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2656 else 2657 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2658 D.setInvalidType(); 2659 } 2660 } 2661 if (DC->isRecord() && !CurContext->isRecord()) { 2662 // This is an out-of-line definition of a static data member. 2663 if (SC == VarDecl::Static) { 2664 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2665 diag::err_static_out_of_line) 2666 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2667 } else if (SC == VarDecl::None) 2668 SC = VarDecl::Static; 2669 } 2670 if (SC == VarDecl::Static) { 2671 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2672 if (RD->isLocalClass()) 2673 Diag(D.getIdentifierLoc(), 2674 diag::err_static_data_member_not_allowed_in_local_class) 2675 << Name << RD->getDeclName(); 2676 } 2677 } 2678 2679 // Match up the template parameter lists with the scope specifier, then 2680 // determine whether we have a template or a template specialization. 2681 bool isExplicitSpecialization = false; 2682 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2683 bool Invalid = false; 2684 if (TemplateParameterList *TemplateParams 2685 = MatchTemplateParametersToScopeSpecifier( 2686 D.getDeclSpec().getSourceRange().getBegin(), 2687 D.getCXXScopeSpec(), 2688 (TemplateParameterList**)TemplateParamLists.get(), 2689 TemplateParamLists.size(), 2690 /*never a friend*/ false, 2691 isExplicitSpecialization, 2692 Invalid)) { 2693 // All but one template parameter lists have been matching. 2694 --NumMatchedTemplateParamLists; 2695 2696 if (TemplateParams->size() > 0) { 2697 // There is no such thing as a variable template. 2698 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2699 << II 2700 << SourceRange(TemplateParams->getTemplateLoc(), 2701 TemplateParams->getRAngleLoc()); 2702 return 0; 2703 } else { 2704 // There is an extraneous 'template<>' for this variable. Complain 2705 // about it, but allow the declaration of the variable. 2706 Diag(TemplateParams->getTemplateLoc(), 2707 diag::err_template_variable_noparams) 2708 << II 2709 << SourceRange(TemplateParams->getTemplateLoc(), 2710 TemplateParams->getRAngleLoc()); 2711 2712 isExplicitSpecialization = true; 2713 } 2714 } 2715 2716 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2717 II, R, TInfo, SC, SCAsWritten); 2718 2719 if (D.isInvalidType() || Invalid) 2720 NewVD->setInvalidDecl(); 2721 2722 SetNestedNameSpecifier(NewVD, D); 2723 2724 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2725 NewVD->setTemplateParameterListsInfo(Context, 2726 NumMatchedTemplateParamLists, 2727 (TemplateParameterList**)TemplateParamLists.release()); 2728 } 2729 2730 if (D.getDeclSpec().isThreadSpecified()) { 2731 if (NewVD->hasLocalStorage()) 2732 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2733 else if (!Context.Target.isTLSSupported()) 2734 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2735 else 2736 NewVD->setThreadSpecified(true); 2737 } 2738 2739 // Set the lexical context. If the declarator has a C++ scope specifier, the 2740 // lexical context will be different from the semantic context. 2741 NewVD->setLexicalDeclContext(CurContext); 2742 2743 // Handle attributes prior to checking for duplicates in MergeVarDecl 2744 ProcessDeclAttributes(S, NewVD, D); 2745 2746 // Handle GNU asm-label extension (encoded as an attribute). 2747 if (Expr *E = (Expr*) D.getAsmLabel()) { 2748 // The parser guarantees this is a string. 2749 StringLiteral *SE = cast<StringLiteral>(E); 2750 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2751 } 2752 2753 // Diagnose shadowed variables before filtering for scope. 2754 if (!D.getCXXScopeSpec().isSet()) 2755 CheckShadow(S, NewVD, Previous); 2756 2757 // Don't consider existing declarations that are in a different 2758 // scope and are out-of-semantic-context declarations (if the new 2759 // declaration has linkage). 2760 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2761 2762 // Merge the decl with the existing one if appropriate. 2763 if (!Previous.empty()) { 2764 if (Previous.isSingleResult() && 2765 isa<FieldDecl>(Previous.getFoundDecl()) && 2766 D.getCXXScopeSpec().isSet()) { 2767 // The user tried to define a non-static data member 2768 // out-of-line (C++ [dcl.meaning]p1). 2769 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2770 << D.getCXXScopeSpec().getRange(); 2771 Previous.clear(); 2772 NewVD->setInvalidDecl(); 2773 } 2774 } else if (D.getCXXScopeSpec().isSet()) { 2775 // No previous declaration in the qualifying scope. 2776 Diag(D.getIdentifierLoc(), diag::err_no_member) 2777 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2778 << D.getCXXScopeSpec().getRange(); 2779 NewVD->setInvalidDecl(); 2780 } 2781 2782 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2783 2784 // This is an explicit specialization of a static data member. Check it. 2785 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2786 CheckMemberSpecialization(NewVD, Previous)) 2787 NewVD->setInvalidDecl(); 2788 2789 // attributes declared post-definition are currently ignored 2790 if (Previous.isSingleResult()) { 2791 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2792 if (Def && (Def = Def->getDefinition()) && 2793 Def != NewVD && D.hasAttributes()) { 2794 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2795 Diag(Def->getLocation(), diag::note_previous_definition); 2796 } 2797 } 2798 2799 // If this is a locally-scoped extern C variable, update the map of 2800 // such variables. 2801 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2802 !NewVD->isInvalidDecl()) 2803 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2804 2805 // If there's a #pragma GCC visibility in scope, and this isn't a class 2806 // member, set the visibility of this variable. 2807 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2808 AddPushedVisibilityAttribute(NewVD); 2809 2810 MarkUnusedFileScopedDecl(NewVD); 2811 2812 return NewVD; 2813} 2814 2815/// \brief Diagnose variable or built-in function shadowing. Implements 2816/// -Wshadow. 2817/// 2818/// This method is called whenever a VarDecl is added to a "useful" 2819/// scope. 2820/// 2821/// \param S the scope in which the shadowing name is being declared 2822/// \param R the lookup of the name 2823/// 2824void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2825 // Return if warning is ignored. 2826 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2827 return; 2828 2829 // Don't diagnose declarations at file scope. The scope might not 2830 // have a DeclContext if (e.g.) we're parsing a function prototype. 2831 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2832 if (NewDC && NewDC->isFileContext()) 2833 return; 2834 2835 // Only diagnose if we're shadowing an unambiguous field or variable. 2836 if (R.getResultKind() != LookupResult::Found) 2837 return; 2838 2839 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2840 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2841 return; 2842 2843 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2844 2845 // Only warn about certain kinds of shadowing for class members. 2846 if (NewDC && NewDC->isRecord()) { 2847 // In particular, don't warn about shadowing non-class members. 2848 if (!OldDC->isRecord()) 2849 return; 2850 2851 // TODO: should we warn about static data members shadowing 2852 // static data members from base classes? 2853 2854 // TODO: don't diagnose for inaccessible shadowed members. 2855 // This is hard to do perfectly because we might friend the 2856 // shadowing context, but that's just a false negative. 2857 } 2858 2859 // Determine what kind of declaration we're shadowing. 2860 unsigned Kind; 2861 if (isa<RecordDecl>(OldDC)) { 2862 if (isa<FieldDecl>(ShadowedDecl)) 2863 Kind = 3; // field 2864 else 2865 Kind = 2; // static data member 2866 } else if (OldDC->isFileContext()) 2867 Kind = 1; // global 2868 else 2869 Kind = 0; // local 2870 2871 DeclarationName Name = R.getLookupName(); 2872 2873 // Emit warning and note. 2874 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2875 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2876} 2877 2878/// \brief Check -Wshadow without the advantage of a previous lookup. 2879void Sema::CheckShadow(Scope *S, VarDecl *D) { 2880 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2881 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2882 LookupName(R, S); 2883 CheckShadow(S, D, R); 2884} 2885 2886/// \brief Perform semantic checking on a newly-created variable 2887/// declaration. 2888/// 2889/// This routine performs all of the type-checking required for a 2890/// variable declaration once it has been built. It is used both to 2891/// check variables after they have been parsed and their declarators 2892/// have been translated into a declaration, and to check variables 2893/// that have been instantiated from a template. 2894/// 2895/// Sets NewVD->isInvalidDecl() if an error was encountered. 2896void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2897 LookupResult &Previous, 2898 bool &Redeclaration) { 2899 // If the decl is already known invalid, don't check it. 2900 if (NewVD->isInvalidDecl()) 2901 return; 2902 2903 QualType T = NewVD->getType(); 2904 2905 if (T->isObjCObjectType()) { 2906 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2907 return NewVD->setInvalidDecl(); 2908 } 2909 2910 // Emit an error if an address space was applied to decl with local storage. 2911 // This includes arrays of objects with address space qualifiers, but not 2912 // automatic variables that point to other address spaces. 2913 // ISO/IEC TR 18037 S5.1.2 2914 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2915 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2916 return NewVD->setInvalidDecl(); 2917 } 2918 2919 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2920 && !NewVD->hasAttr<BlocksAttr>()) 2921 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2922 2923 bool isVM = T->isVariablyModifiedType(); 2924 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2925 NewVD->hasAttr<BlocksAttr>()) 2926 setFunctionHasBranchProtectedScope(); 2927 2928 if ((isVM && NewVD->hasLinkage()) || 2929 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2930 bool SizeIsNegative; 2931 QualType FixedTy = 2932 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2933 2934 if (FixedTy.isNull() && T->isVariableArrayType()) { 2935 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2936 // FIXME: This won't give the correct result for 2937 // int a[10][n]; 2938 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2939 2940 if (NewVD->isFileVarDecl()) 2941 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2942 << SizeRange; 2943 else if (NewVD->getStorageClass() == VarDecl::Static) 2944 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2945 << SizeRange; 2946 else 2947 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2948 << SizeRange; 2949 return NewVD->setInvalidDecl(); 2950 } 2951 2952 if (FixedTy.isNull()) { 2953 if (NewVD->isFileVarDecl()) 2954 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2955 else 2956 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2957 return NewVD->setInvalidDecl(); 2958 } 2959 2960 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2961 NewVD->setType(FixedTy); 2962 } 2963 2964 if (Previous.empty() && NewVD->isExternC()) { 2965 // Since we did not find anything by this name and we're declaring 2966 // an extern "C" variable, look for a non-visible extern "C" 2967 // declaration with the same name. 2968 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2969 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2970 if (Pos != LocallyScopedExternalDecls.end()) 2971 Previous.addDecl(Pos->second); 2972 } 2973 2974 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2975 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2976 << T; 2977 return NewVD->setInvalidDecl(); 2978 } 2979 2980 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2981 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2982 return NewVD->setInvalidDecl(); 2983 } 2984 2985 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2986 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2987 return NewVD->setInvalidDecl(); 2988 } 2989 2990 // Function pointers and references cannot have qualified function type, only 2991 // function pointer-to-members can do that. 2992 QualType Pointee; 2993 unsigned PtrOrRef = 0; 2994 if (const PointerType *Ptr = T->getAs<PointerType>()) 2995 Pointee = Ptr->getPointeeType(); 2996 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 2997 Pointee = Ref->getPointeeType(); 2998 PtrOrRef = 1; 2999 } 3000 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3001 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3002 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3003 << PtrOrRef; 3004 return NewVD->setInvalidDecl(); 3005 } 3006 3007 if (!Previous.empty()) { 3008 Redeclaration = true; 3009 MergeVarDecl(NewVD, Previous); 3010 } 3011} 3012 3013/// \brief Data used with FindOverriddenMethod 3014struct FindOverriddenMethodData { 3015 Sema *S; 3016 CXXMethodDecl *Method; 3017}; 3018 3019/// \brief Member lookup function that determines whether a given C++ 3020/// method overrides a method in a base class, to be used with 3021/// CXXRecordDecl::lookupInBases(). 3022static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3023 CXXBasePath &Path, 3024 void *UserData) { 3025 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3026 3027 FindOverriddenMethodData *Data 3028 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3029 3030 DeclarationName Name = Data->Method->getDeclName(); 3031 3032 // FIXME: Do we care about other names here too? 3033 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3034 // We really want to find the base class destructor here. 3035 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3036 CanQualType CT = Data->S->Context.getCanonicalType(T); 3037 3038 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3039 } 3040 3041 for (Path.Decls = BaseRecord->lookup(Name); 3042 Path.Decls.first != Path.Decls.second; 3043 ++Path.Decls.first) { 3044 NamedDecl *D = *Path.Decls.first; 3045 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3046 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3047 return true; 3048 } 3049 } 3050 3051 return false; 3052} 3053 3054/// AddOverriddenMethods - See if a method overrides any in the base classes, 3055/// and if so, check that it's a valid override and remember it. 3056void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3057 // Look for virtual methods in base classes that this method might override. 3058 CXXBasePaths Paths; 3059 FindOverriddenMethodData Data; 3060 Data.Method = MD; 3061 Data.S = this; 3062 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3063 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3064 E = Paths.found_decls_end(); I != E; ++I) { 3065 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3066 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3067 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3068 !CheckOverridingFunctionAttributes(MD, OldMD)) 3069 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3070 } 3071 } 3072 } 3073} 3074 3075NamedDecl* 3076Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3077 QualType R, TypeSourceInfo *TInfo, 3078 LookupResult &Previous, 3079 MultiTemplateParamsArg TemplateParamLists, 3080 bool IsFunctionDefinition, bool &Redeclaration) { 3081 assert(R.getTypePtr()->isFunctionType()); 3082 3083 // TODO: consider using NameInfo for diagnostic. 3084 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3085 DeclarationName Name = NameInfo.getName(); 3086 FunctionDecl::StorageClass SC = FunctionDecl::None; 3087 switch (D.getDeclSpec().getStorageClassSpec()) { 3088 default: assert(0 && "Unknown storage class!"); 3089 case DeclSpec::SCS_auto: 3090 case DeclSpec::SCS_register: 3091 case DeclSpec::SCS_mutable: 3092 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3093 diag::err_typecheck_sclass_func); 3094 D.setInvalidType(); 3095 break; 3096 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 3097 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 3098 case DeclSpec::SCS_static: { 3099 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 3100 // C99 6.7.1p5: 3101 // The declaration of an identifier for a function that has 3102 // block scope shall have no explicit storage-class specifier 3103 // other than extern 3104 // See also (C++ [dcl.stc]p4). 3105 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3106 diag::err_static_block_func); 3107 SC = FunctionDecl::None; 3108 } else 3109 SC = FunctionDecl::Static; 3110 break; 3111 } 3112 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 3113 } 3114 3115 if (D.getDeclSpec().isThreadSpecified()) 3116 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3117 3118 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3119 bool isInline = D.getDeclSpec().isInlineSpecified(); 3120 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3121 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3122 3123 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3124 FunctionDecl::StorageClass SCAsWritten 3125 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3126 3127 // Check that the return type is not an abstract class type. 3128 // For record types, this is done by the AbstractClassUsageDiagnoser once 3129 // the class has been completely parsed. 3130 if (!DC->isRecord() && 3131 RequireNonAbstractType(D.getIdentifierLoc(), 3132 R->getAs<FunctionType>()->getResultType(), 3133 diag::err_abstract_type_in_decl, 3134 AbstractReturnType)) 3135 D.setInvalidType(); 3136 3137 // Do not allow returning a objc interface by-value. 3138 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3139 Diag(D.getIdentifierLoc(), 3140 diag::err_object_cannot_be_passed_returned_by_value) << 0 3141 << R->getAs<FunctionType>()->getResultType(); 3142 D.setInvalidType(); 3143 } 3144 3145 bool isVirtualOkay = false; 3146 FunctionDecl *NewFD; 3147 3148 if (isFriend) { 3149 // C++ [class.friend]p5 3150 // A function can be defined in a friend declaration of a 3151 // class . . . . Such a function is implicitly inline. 3152 isInline |= IsFunctionDefinition; 3153 } 3154 3155 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3156 // This is a C++ constructor declaration. 3157 assert(DC->isRecord() && 3158 "Constructors can only be declared in a member context"); 3159 3160 R = CheckConstructorDeclarator(D, R, SC); 3161 3162 // Create the new declaration 3163 NewFD = CXXConstructorDecl::Create(Context, 3164 cast<CXXRecordDecl>(DC), 3165 NameInfo, R, TInfo, 3166 isExplicit, isInline, 3167 /*isImplicitlyDeclared=*/false); 3168 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3169 // This is a C++ destructor declaration. 3170 if (DC->isRecord()) { 3171 R = CheckDestructorDeclarator(D, R, SC); 3172 3173 NewFD = CXXDestructorDecl::Create(Context, 3174 cast<CXXRecordDecl>(DC), 3175 NameInfo, R, 3176 isInline, 3177 /*isImplicitlyDeclared=*/false); 3178 NewFD->setTypeSourceInfo(TInfo); 3179 3180 isVirtualOkay = true; 3181 } else { 3182 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3183 3184 // Create a FunctionDecl to satisfy the function definition parsing 3185 // code path. 3186 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3187 Name, R, TInfo, SC, SCAsWritten, isInline, 3188 /*hasPrototype=*/true); 3189 D.setInvalidType(); 3190 } 3191 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3192 if (!DC->isRecord()) { 3193 Diag(D.getIdentifierLoc(), 3194 diag::err_conv_function_not_member); 3195 return 0; 3196 } 3197 3198 CheckConversionDeclarator(D, R, SC); 3199 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3200 NameInfo, R, TInfo, 3201 isInline, isExplicit); 3202 3203 isVirtualOkay = true; 3204 } else if (DC->isRecord()) { 3205 // If the of the function is the same as the name of the record, then this 3206 // must be an invalid constructor that has a return type. 3207 // (The parser checks for a return type and makes the declarator a 3208 // constructor if it has no return type). 3209 // must have an invalid constructor that has a return type 3210 if (Name.getAsIdentifierInfo() && 3211 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3212 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3213 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3214 << SourceRange(D.getIdentifierLoc()); 3215 return 0; 3216 } 3217 3218 bool isStatic = SC == FunctionDecl::Static; 3219 3220 // [class.free]p1: 3221 // Any allocation function for a class T is a static member 3222 // (even if not explicitly declared static). 3223 if (Name.getCXXOverloadedOperator() == OO_New || 3224 Name.getCXXOverloadedOperator() == OO_Array_New) 3225 isStatic = true; 3226 3227 // [class.free]p6 Any deallocation function for a class X is a static member 3228 // (even if not explicitly declared static). 3229 if (Name.getCXXOverloadedOperator() == OO_Delete || 3230 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3231 isStatic = true; 3232 3233 // This is a C++ method declaration. 3234 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3235 NameInfo, R, TInfo, 3236 isStatic, SCAsWritten, isInline); 3237 3238 isVirtualOkay = !isStatic; 3239 } else { 3240 // Determine whether the function was written with a 3241 // prototype. This true when: 3242 // - we're in C++ (where every function has a prototype), 3243 // - there is a prototype in the declarator, or 3244 // - the type R of the function is some kind of typedef or other reference 3245 // to a type name (which eventually refers to a function type). 3246 bool HasPrototype = 3247 getLangOptions().CPlusPlus || 3248 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3249 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3250 3251 NewFD = FunctionDecl::Create(Context, DC, 3252 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3253 HasPrototype); 3254 } 3255 3256 if (D.isInvalidType()) 3257 NewFD->setInvalidDecl(); 3258 3259 SetNestedNameSpecifier(NewFD, D); 3260 3261 // Set the lexical context. If the declarator has a C++ 3262 // scope specifier, or is the object of a friend declaration, the 3263 // lexical context will be different from the semantic context. 3264 NewFD->setLexicalDeclContext(CurContext); 3265 3266 // Match up the template parameter lists with the scope specifier, then 3267 // determine whether we have a template or a template specialization. 3268 FunctionTemplateDecl *FunctionTemplate = 0; 3269 bool isExplicitSpecialization = false; 3270 bool isFunctionTemplateSpecialization = false; 3271 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3272 bool Invalid = false; 3273 if (TemplateParameterList *TemplateParams 3274 = MatchTemplateParametersToScopeSpecifier( 3275 D.getDeclSpec().getSourceRange().getBegin(), 3276 D.getCXXScopeSpec(), 3277 (TemplateParameterList**)TemplateParamLists.get(), 3278 TemplateParamLists.size(), 3279 isFriend, 3280 isExplicitSpecialization, 3281 Invalid)) { 3282 // All but one template parameter lists have been matching. 3283 --NumMatchedTemplateParamLists; 3284 3285 if (TemplateParams->size() > 0) { 3286 // This is a function template 3287 3288 // Check that we can declare a template here. 3289 if (CheckTemplateDeclScope(S, TemplateParams)) 3290 return 0; 3291 3292 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3293 NewFD->getLocation(), 3294 Name, TemplateParams, 3295 NewFD); 3296 FunctionTemplate->setLexicalDeclContext(CurContext); 3297 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3298 } else { 3299 // This is a function template specialization. 3300 isFunctionTemplateSpecialization = true; 3301 3302 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3303 if (isFriend && isFunctionTemplateSpecialization) { 3304 // We want to remove the "template<>", found here. 3305 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3306 3307 // If we remove the template<> and the name is not a 3308 // template-id, we're actually silently creating a problem: 3309 // the friend declaration will refer to an untemplated decl, 3310 // and clearly the user wants a template specialization. So 3311 // we need to insert '<>' after the name. 3312 SourceLocation InsertLoc; 3313 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3314 InsertLoc = D.getName().getSourceRange().getEnd(); 3315 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3316 } 3317 3318 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3319 << Name << RemoveRange 3320 << FixItHint::CreateRemoval(RemoveRange) 3321 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3322 } 3323 } 3324 } 3325 3326 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3327 NewFD->setTemplateParameterListsInfo(Context, 3328 NumMatchedTemplateParamLists, 3329 (TemplateParameterList**)TemplateParamLists.release()); 3330 } 3331 3332 if (Invalid) { 3333 NewFD->setInvalidDecl(); 3334 if (FunctionTemplate) 3335 FunctionTemplate->setInvalidDecl(); 3336 } 3337 3338 // C++ [dcl.fct.spec]p5: 3339 // The virtual specifier shall only be used in declarations of 3340 // nonstatic class member functions that appear within a 3341 // member-specification of a class declaration; see 10.3. 3342 // 3343 if (isVirtual && !NewFD->isInvalidDecl()) { 3344 if (!isVirtualOkay) { 3345 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3346 diag::err_virtual_non_function); 3347 } else if (!CurContext->isRecord()) { 3348 // 'virtual' was specified outside of the class. 3349 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3350 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3351 } else { 3352 // Okay: Add virtual to the method. 3353 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3354 CurClass->setMethodAsVirtual(NewFD); 3355 } 3356 } 3357 3358 // C++ [dcl.fct.spec]p3: 3359 // The inline specifier shall not appear on a block scope function declaration. 3360 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3361 if (CurContext->isFunctionOrMethod()) { 3362 // 'inline' is not allowed on block scope function declaration. 3363 Diag(D.getDeclSpec().getInlineSpecLoc(), 3364 diag::err_inline_declaration_block_scope) << Name 3365 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3366 } 3367 } 3368 3369 // C++ [dcl.fct.spec]p6: 3370 // The explicit specifier shall be used only in the declaration of a 3371 // constructor or conversion function within its class definition; see 12.3.1 3372 // and 12.3.2. 3373 if (isExplicit && !NewFD->isInvalidDecl()) { 3374 if (!CurContext->isRecord()) { 3375 // 'explicit' was specified outside of the class. 3376 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3377 diag::err_explicit_out_of_class) 3378 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3379 } else if (!isa<CXXConstructorDecl>(NewFD) && 3380 !isa<CXXConversionDecl>(NewFD)) { 3381 // 'explicit' was specified on a function that wasn't a constructor 3382 // or conversion function. 3383 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3384 diag::err_explicit_non_ctor_or_conv_function) 3385 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3386 } 3387 } 3388 3389 // Filter out previous declarations that don't match the scope. 3390 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3391 3392 if (isFriend) { 3393 // DC is the namespace in which the function is being declared. 3394 assert((DC->isFileContext() || !Previous.empty()) && 3395 "previously-undeclared friend function being created " 3396 "in a non-namespace context"); 3397 3398 // For now, claim that the objects have no previous declaration. 3399 if (FunctionTemplate) { 3400 FunctionTemplate->setObjectOfFriendDecl(false); 3401 FunctionTemplate->setAccess(AS_public); 3402 } 3403 NewFD->setObjectOfFriendDecl(false); 3404 NewFD->setAccess(AS_public); 3405 } 3406 3407 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3408 !CurContext->isRecord()) { 3409 // C++ [class.static]p1: 3410 // A data or function member of a class may be declared static 3411 // in a class definition, in which case it is a static member of 3412 // the class. 3413 3414 // Complain about the 'static' specifier if it's on an out-of-line 3415 // member function definition. 3416 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3417 diag::err_static_out_of_line) 3418 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3419 } 3420 3421 // Handle GNU asm-label extension (encoded as an attribute). 3422 if (Expr *E = (Expr*) D.getAsmLabel()) { 3423 // The parser guarantees this is a string. 3424 StringLiteral *SE = cast<StringLiteral>(E); 3425 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3426 } 3427 3428 // Copy the parameter declarations from the declarator D to the function 3429 // declaration NewFD, if they are available. First scavenge them into Params. 3430 llvm::SmallVector<ParmVarDecl*, 16> Params; 3431 if (D.getNumTypeObjects() > 0) { 3432 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3433 3434 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3435 // function that takes no arguments, not a function that takes a 3436 // single void argument. 3437 // We let through "const void" here because Sema::GetTypeForDeclarator 3438 // already checks for that case. 3439 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3440 FTI.ArgInfo[0].Param && 3441 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3442 // Empty arg list, don't push any params. 3443 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3444 3445 // In C++, the empty parameter-type-list must be spelled "void"; a 3446 // typedef of void is not permitted. 3447 if (getLangOptions().CPlusPlus && 3448 Param->getType().getUnqualifiedType() != Context.VoidTy) 3449 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3450 // FIXME: Leaks decl? 3451 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3452 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3453 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3454 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3455 Param->setDeclContext(NewFD); 3456 Params.push_back(Param); 3457 3458 if (Param->isInvalidDecl()) 3459 NewFD->setInvalidDecl(); 3460 } 3461 } 3462 3463 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3464 // When we're declaring a function with a typedef, typeof, etc as in the 3465 // following example, we'll need to synthesize (unnamed) 3466 // parameters for use in the declaration. 3467 // 3468 // @code 3469 // typedef void fn(int); 3470 // fn f; 3471 // @endcode 3472 3473 // Synthesize a parameter for each argument type. 3474 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3475 AE = FT->arg_type_end(); AI != AE; ++AI) { 3476 ParmVarDecl *Param = 3477 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3478 Params.push_back(Param); 3479 } 3480 } else { 3481 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3482 "Should not need args for typedef of non-prototype fn"); 3483 } 3484 // Finally, we know we have the right number of parameters, install them. 3485 NewFD->setParams(Params.data(), Params.size()); 3486 3487 // If the declarator is a template-id, translate the parser's template 3488 // argument list into our AST format. 3489 bool HasExplicitTemplateArgs = false; 3490 TemplateArgumentListInfo TemplateArgs; 3491 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3492 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3493 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3494 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3495 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3496 TemplateId->getTemplateArgs(), 3497 TemplateId->NumArgs); 3498 translateTemplateArguments(TemplateArgsPtr, 3499 TemplateArgs); 3500 TemplateArgsPtr.release(); 3501 3502 HasExplicitTemplateArgs = true; 3503 3504 if (FunctionTemplate) { 3505 // FIXME: Diagnose function template with explicit template 3506 // arguments. 3507 HasExplicitTemplateArgs = false; 3508 } else if (!isFunctionTemplateSpecialization && 3509 !D.getDeclSpec().isFriendSpecified()) { 3510 // We have encountered something that the user meant to be a 3511 // specialization (because it has explicitly-specified template 3512 // arguments) but that was not introduced with a "template<>" (or had 3513 // too few of them). 3514 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3515 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3516 << FixItHint::CreateInsertion( 3517 D.getDeclSpec().getSourceRange().getBegin(), 3518 "template<> "); 3519 isFunctionTemplateSpecialization = true; 3520 } else { 3521 // "friend void foo<>(int);" is an implicit specialization decl. 3522 isFunctionTemplateSpecialization = true; 3523 } 3524 } else if (isFriend && isFunctionTemplateSpecialization) { 3525 // This combination is only possible in a recovery case; the user 3526 // wrote something like: 3527 // template <> friend void foo(int); 3528 // which we're recovering from as if the user had written: 3529 // friend void foo<>(int); 3530 // Go ahead and fake up a template id. 3531 HasExplicitTemplateArgs = true; 3532 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3533 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3534 } 3535 3536 // If it's a friend (and only if it's a friend), it's possible 3537 // that either the specialized function type or the specialized 3538 // template is dependent, and therefore matching will fail. In 3539 // this case, don't check the specialization yet. 3540 if (isFunctionTemplateSpecialization && isFriend && 3541 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3542 assert(HasExplicitTemplateArgs && 3543 "friend function specialization without template args"); 3544 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3545 Previous)) 3546 NewFD->setInvalidDecl(); 3547 } else if (isFunctionTemplateSpecialization) { 3548 if (CheckFunctionTemplateSpecialization(NewFD, 3549 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3550 Previous)) 3551 NewFD->setInvalidDecl(); 3552 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3553 if (CheckMemberSpecialization(NewFD, Previous)) 3554 NewFD->setInvalidDecl(); 3555 } 3556 3557 // Perform semantic checking on the function declaration. 3558 bool OverloadableAttrRequired = false; // FIXME: HACK! 3559 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3560 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3561 3562 assert((NewFD->isInvalidDecl() || !Redeclaration || 3563 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3564 "previous declaration set still overloaded"); 3565 3566 NamedDecl *PrincipalDecl = (FunctionTemplate 3567 ? cast<NamedDecl>(FunctionTemplate) 3568 : NewFD); 3569 3570 if (isFriend && Redeclaration) { 3571 AccessSpecifier Access = AS_public; 3572 if (!NewFD->isInvalidDecl()) 3573 Access = NewFD->getPreviousDeclaration()->getAccess(); 3574 3575 NewFD->setAccess(Access); 3576 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3577 3578 PrincipalDecl->setObjectOfFriendDecl(true); 3579 } 3580 3581 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3582 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3583 PrincipalDecl->setNonMemberOperator(); 3584 3585 // If we have a function template, check the template parameter 3586 // list. This will check and merge default template arguments. 3587 if (FunctionTemplate) { 3588 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3589 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3590 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3591 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3592 : TPC_FunctionTemplate); 3593 } 3594 3595 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3596 // Fake up an access specifier if it's supposed to be a class member. 3597 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3598 NewFD->setAccess(AS_public); 3599 3600 // An out-of-line member function declaration must also be a 3601 // definition (C++ [dcl.meaning]p1). 3602 // Note that this is not the case for explicit specializations of 3603 // function templates or member functions of class templates, per 3604 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3605 // for compatibility with old SWIG code which likes to generate them. 3606 if (!IsFunctionDefinition && !isFriend && 3607 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3608 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3609 << D.getCXXScopeSpec().getRange(); 3610 } 3611 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3612 // The user tried to provide an out-of-line definition for a 3613 // function that is a member of a class or namespace, but there 3614 // was no such member function declared (C++ [class.mfct]p2, 3615 // C++ [namespace.memdef]p2). For example: 3616 // 3617 // class X { 3618 // void f() const; 3619 // }; 3620 // 3621 // void X::f() { } // ill-formed 3622 // 3623 // Complain about this problem, and attempt to suggest close 3624 // matches (e.g., those that differ only in cv-qualifiers and 3625 // whether the parameter types are references). 3626 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3627 << Name << DC << D.getCXXScopeSpec().getRange(); 3628 NewFD->setInvalidDecl(); 3629 3630 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3631 ForRedeclaration); 3632 LookupQualifiedName(Prev, DC); 3633 assert(!Prev.isAmbiguous() && 3634 "Cannot have an ambiguity in previous-declaration lookup"); 3635 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3636 Func != FuncEnd; ++Func) { 3637 if (isa<FunctionDecl>(*Func) && 3638 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3639 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3640 } 3641 } 3642 } 3643 3644 // Handle attributes. We need to have merged decls when handling attributes 3645 // (for example to check for conflicts, etc). 3646 // FIXME: This needs to happen before we merge declarations. Then, 3647 // let attribute merging cope with attribute conflicts. 3648 ProcessDeclAttributes(S, NewFD, D); 3649 3650 // attributes declared post-definition are currently ignored 3651 if (Redeclaration && Previous.isSingleResult()) { 3652 const FunctionDecl *Def; 3653 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3654 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3655 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3656 Diag(Def->getLocation(), diag::note_previous_definition); 3657 } 3658 } 3659 3660 AddKnownFunctionAttributes(NewFD); 3661 3662 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3663 // If a function name is overloadable in C, then every function 3664 // with that name must be marked "overloadable". 3665 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3666 << Redeclaration << NewFD; 3667 if (!Previous.empty()) 3668 Diag(Previous.getRepresentativeDecl()->getLocation(), 3669 diag::note_attribute_overloadable_prev_overload); 3670 NewFD->addAttr(::new (Context) OverloadableAttr()); 3671 } 3672 3673 if (NewFD->hasAttr<OverloadableAttr>() && 3674 !NewFD->getType()->getAs<FunctionProtoType>()) { 3675 Diag(NewFD->getLocation(), 3676 diag::err_attribute_overloadable_no_prototype) 3677 << NewFD; 3678 3679 // Turn this into a variadic function with no parameters. 3680 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3681 QualType R = Context.getFunctionType(FT->getResultType(), 3682 0, 0, true, 0, false, false, 0, 0, 3683 FT->getExtInfo()); 3684 NewFD->setType(R); 3685 } 3686 3687 // If there's a #pragma GCC visibility in scope, and this isn't a class 3688 // member, set the visibility of this function. 3689 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3690 AddPushedVisibilityAttribute(NewFD); 3691 3692 // If this is a locally-scoped extern C function, update the 3693 // map of such names. 3694 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3695 && !NewFD->isInvalidDecl()) 3696 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3697 3698 // Set this FunctionDecl's range up to the right paren. 3699 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3700 3701 if (FunctionTemplate && NewFD->isInvalidDecl()) 3702 FunctionTemplate->setInvalidDecl(); 3703 3704 if (FunctionTemplate) 3705 return FunctionTemplate; 3706 3707 MarkUnusedFileScopedDecl(NewFD); 3708 3709 return NewFD; 3710} 3711 3712/// \brief Perform semantic checking of a new function declaration. 3713/// 3714/// Performs semantic analysis of the new function declaration 3715/// NewFD. This routine performs all semantic checking that does not 3716/// require the actual declarator involved in the declaration, and is 3717/// used both for the declaration of functions as they are parsed 3718/// (called via ActOnDeclarator) and for the declaration of functions 3719/// that have been instantiated via C++ template instantiation (called 3720/// via InstantiateDecl). 3721/// 3722/// \param IsExplicitSpecialiation whether this new function declaration is 3723/// an explicit specialization of the previous declaration. 3724/// 3725/// This sets NewFD->isInvalidDecl() to true if there was an error. 3726void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3727 LookupResult &Previous, 3728 bool IsExplicitSpecialization, 3729 bool &Redeclaration, 3730 bool &OverloadableAttrRequired) { 3731 // If NewFD is already known erroneous, don't do any of this checking. 3732 if (NewFD->isInvalidDecl()) { 3733 // If this is a class member, mark the class invalid immediately. 3734 // This avoids some consistency errors later. 3735 if (isa<CXXMethodDecl>(NewFD)) 3736 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3737 3738 return; 3739 } 3740 3741 if (NewFD->getResultType()->isVariablyModifiedType()) { 3742 // Functions returning a variably modified type violate C99 6.7.5.2p2 3743 // because all functions have linkage. 3744 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3745 return NewFD->setInvalidDecl(); 3746 } 3747 3748 if (NewFD->isMain()) 3749 CheckMain(NewFD); 3750 3751 // Check for a previous declaration of this name. 3752 if (Previous.empty() && NewFD->isExternC()) { 3753 // Since we did not find anything by this name and we're declaring 3754 // an extern "C" function, look for a non-visible extern "C" 3755 // declaration with the same name. 3756 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3757 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3758 if (Pos != LocallyScopedExternalDecls.end()) 3759 Previous.addDecl(Pos->second); 3760 } 3761 3762 // Merge or overload the declaration with an existing declaration of 3763 // the same name, if appropriate. 3764 if (!Previous.empty()) { 3765 // Determine whether NewFD is an overload of PrevDecl or 3766 // a declaration that requires merging. If it's an overload, 3767 // there's no more work to do here; we'll just add the new 3768 // function to the scope. 3769 3770 NamedDecl *OldDecl = 0; 3771 if (!AllowOverloadingOfFunction(Previous, Context)) { 3772 Redeclaration = true; 3773 OldDecl = Previous.getFoundDecl(); 3774 } else { 3775 if (!getLangOptions().CPlusPlus) 3776 OverloadableAttrRequired = true; 3777 3778 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3779 /*NewIsUsingDecl*/ false)) { 3780 case Ovl_Match: 3781 Redeclaration = true; 3782 break; 3783 3784 case Ovl_NonFunction: 3785 Redeclaration = true; 3786 break; 3787 3788 case Ovl_Overload: 3789 Redeclaration = false; 3790 break; 3791 } 3792 } 3793 3794 if (Redeclaration) { 3795 // NewFD and OldDecl represent declarations that need to be 3796 // merged. 3797 if (MergeFunctionDecl(NewFD, OldDecl)) 3798 return NewFD->setInvalidDecl(); 3799 3800 Previous.clear(); 3801 Previous.addDecl(OldDecl); 3802 3803 if (FunctionTemplateDecl *OldTemplateDecl 3804 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3805 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3806 FunctionTemplateDecl *NewTemplateDecl 3807 = NewFD->getDescribedFunctionTemplate(); 3808 assert(NewTemplateDecl && "Template/non-template mismatch"); 3809 if (CXXMethodDecl *Method 3810 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3811 Method->setAccess(OldTemplateDecl->getAccess()); 3812 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3813 } 3814 3815 // If this is an explicit specialization of a member that is a function 3816 // template, mark it as a member specialization. 3817 if (IsExplicitSpecialization && 3818 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3819 NewTemplateDecl->setMemberSpecialization(); 3820 assert(OldTemplateDecl->isMemberSpecialization()); 3821 } 3822 } else { 3823 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3824 NewFD->setAccess(OldDecl->getAccess()); 3825 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3826 } 3827 } 3828 } 3829 3830 // Semantic checking for this function declaration (in isolation). 3831 if (getLangOptions().CPlusPlus) { 3832 // C++-specific checks. 3833 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3834 CheckConstructor(Constructor); 3835 } else if (CXXDestructorDecl *Destructor = 3836 dyn_cast<CXXDestructorDecl>(NewFD)) { 3837 CXXRecordDecl *Record = Destructor->getParent(); 3838 QualType ClassType = Context.getTypeDeclType(Record); 3839 3840 // FIXME: Shouldn't we be able to perform this check even when the class 3841 // type is dependent? Both gcc and edg can handle that. 3842 if (!ClassType->isDependentType()) { 3843 DeclarationName Name 3844 = Context.DeclarationNames.getCXXDestructorName( 3845 Context.getCanonicalType(ClassType)); 3846// NewFD->getDeclName().dump(); 3847// Name.dump(); 3848 if (NewFD->getDeclName() != Name) { 3849 Diag(NewFD->getLocation(), diag::err_destructor_name); 3850 return NewFD->setInvalidDecl(); 3851 } 3852 } 3853 3854 Record->setUserDeclaredDestructor(true); 3855 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3856 // user-defined destructor. 3857 Record->setPOD(false); 3858 3859 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3860 // declared destructor. 3861 // FIXME: C++0x: don't do this for "= default" destructors 3862 Record->setHasTrivialDestructor(false); 3863 } else if (CXXConversionDecl *Conversion 3864 = dyn_cast<CXXConversionDecl>(NewFD)) { 3865 ActOnConversionDeclarator(Conversion); 3866 } 3867 3868 // Find any virtual functions that this function overrides. 3869 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3870 if (!Method->isFunctionTemplateSpecialization() && 3871 !Method->getDescribedFunctionTemplate()) 3872 AddOverriddenMethods(Method->getParent(), Method); 3873 } 3874 3875 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3876 if (NewFD->isOverloadedOperator() && 3877 CheckOverloadedOperatorDeclaration(NewFD)) 3878 return NewFD->setInvalidDecl(); 3879 3880 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3881 if (NewFD->getLiteralIdentifier() && 3882 CheckLiteralOperatorDeclaration(NewFD)) 3883 return NewFD->setInvalidDecl(); 3884 3885 // In C++, check default arguments now that we have merged decls. Unless 3886 // the lexical context is the class, because in this case this is done 3887 // during delayed parsing anyway. 3888 if (!CurContext->isRecord()) 3889 CheckCXXDefaultArguments(NewFD); 3890 } 3891} 3892 3893void Sema::CheckMain(FunctionDecl* FD) { 3894 // C++ [basic.start.main]p3: A program that declares main to be inline 3895 // or static is ill-formed. 3896 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3897 // shall not appear in a declaration of main. 3898 // static main is not an error under C99, but we should warn about it. 3899 bool isInline = FD->isInlineSpecified(); 3900 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3901 if (isInline || isStatic) { 3902 unsigned diagID = diag::warn_unusual_main_decl; 3903 if (isInline || getLangOptions().CPlusPlus) 3904 diagID = diag::err_unusual_main_decl; 3905 3906 int which = isStatic + (isInline << 1) - 1; 3907 Diag(FD->getLocation(), diagID) << which; 3908 } 3909 3910 QualType T = FD->getType(); 3911 assert(T->isFunctionType() && "function decl is not of function type"); 3912 const FunctionType* FT = T->getAs<FunctionType>(); 3913 3914 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3915 // TODO: add a replacement fixit to turn the return type into 'int'. 3916 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3917 FD->setInvalidDecl(true); 3918 } 3919 3920 // Treat protoless main() as nullary. 3921 if (isa<FunctionNoProtoType>(FT)) return; 3922 3923 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3924 unsigned nparams = FTP->getNumArgs(); 3925 assert(FD->getNumParams() == nparams); 3926 3927 bool HasExtraParameters = (nparams > 3); 3928 3929 // Darwin passes an undocumented fourth argument of type char**. If 3930 // other platforms start sprouting these, the logic below will start 3931 // getting shifty. 3932 if (nparams == 4 && 3933 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3934 HasExtraParameters = false; 3935 3936 if (HasExtraParameters) { 3937 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3938 FD->setInvalidDecl(true); 3939 nparams = 3; 3940 } 3941 3942 // FIXME: a lot of the following diagnostics would be improved 3943 // if we had some location information about types. 3944 3945 QualType CharPP = 3946 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3947 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3948 3949 for (unsigned i = 0; i < nparams; ++i) { 3950 QualType AT = FTP->getArgType(i); 3951 3952 bool mismatch = true; 3953 3954 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3955 mismatch = false; 3956 else if (Expected[i] == CharPP) { 3957 // As an extension, the following forms are okay: 3958 // char const ** 3959 // char const * const * 3960 // char * const * 3961 3962 QualifierCollector qs; 3963 const PointerType* PT; 3964 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3965 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3966 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3967 qs.removeConst(); 3968 mismatch = !qs.empty(); 3969 } 3970 } 3971 3972 if (mismatch) { 3973 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3974 // TODO: suggest replacing given type with expected type 3975 FD->setInvalidDecl(true); 3976 } 3977 } 3978 3979 if (nparams == 1 && !FD->isInvalidDecl()) { 3980 Diag(FD->getLocation(), diag::warn_main_one_arg); 3981 } 3982} 3983 3984bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3985 // FIXME: Need strict checking. In C89, we need to check for 3986 // any assignment, increment, decrement, function-calls, or 3987 // commas outside of a sizeof. In C99, it's the same list, 3988 // except that the aforementioned are allowed in unevaluated 3989 // expressions. Everything else falls under the 3990 // "may accept other forms of constant expressions" exception. 3991 // (We never end up here for C++, so the constant expression 3992 // rules there don't matter.) 3993 if (Init->isConstantInitializer(Context, false)) 3994 return false; 3995 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3996 << Init->getSourceRange(); 3997 return true; 3998} 3999 4000void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 4001 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 4002} 4003 4004/// AddInitializerToDecl - Adds the initializer Init to the 4005/// declaration dcl. If DirectInit is true, this is C++ direct 4006/// initialization rather than copy initialization. 4007void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 4008 Decl *RealDecl = dcl.getAs<Decl>(); 4009 // If there is no declaration, there was an error parsing it. Just ignore 4010 // the initializer. 4011 if (RealDecl == 0) 4012 return; 4013 4014 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4015 // With declarators parsed the way they are, the parser cannot 4016 // distinguish between a normal initializer and a pure-specifier. 4017 // Thus this grotesque test. 4018 IntegerLiteral *IL; 4019 Expr *Init = static_cast<Expr *>(init.get()); 4020 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4021 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4022 CheckPureMethod(Method, Init->getSourceRange()); 4023 else { 4024 Diag(Method->getLocation(), diag::err_member_function_initialization) 4025 << Method->getDeclName() << Init->getSourceRange(); 4026 Method->setInvalidDecl(); 4027 } 4028 return; 4029 } 4030 4031 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4032 if (!VDecl) { 4033 if (getLangOptions().CPlusPlus && 4034 RealDecl->getLexicalDeclContext()->isRecord() && 4035 isa<NamedDecl>(RealDecl)) 4036 Diag(RealDecl->getLocation(), diag::err_member_initialization) 4037 << cast<NamedDecl>(RealDecl)->getDeclName(); 4038 else 4039 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4040 RealDecl->setInvalidDecl(); 4041 return; 4042 } 4043 4044 // A definition must end up with a complete type, which means it must be 4045 // complete with the restriction that an array type might be completed by the 4046 // initializer; note that later code assumes this restriction. 4047 QualType BaseDeclType = VDecl->getType(); 4048 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4049 BaseDeclType = Array->getElementType(); 4050 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4051 diag::err_typecheck_decl_incomplete_type)) { 4052 RealDecl->setInvalidDecl(); 4053 return; 4054 } 4055 4056 // The variable can not have an abstract class type. 4057 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4058 diag::err_abstract_type_in_decl, 4059 AbstractVariableType)) 4060 VDecl->setInvalidDecl(); 4061 4062 const VarDecl *Def; 4063 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4064 Diag(VDecl->getLocation(), diag::err_redefinition) 4065 << VDecl->getDeclName(); 4066 Diag(Def->getLocation(), diag::note_previous_definition); 4067 VDecl->setInvalidDecl(); 4068 return; 4069 } 4070 4071 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4072 setFunctionHasBranchProtectedScope(); 4073 4074 // Take ownership of the expression, now that we're sure we have somewhere 4075 // to put it. 4076 Expr *Init = init.takeAs<Expr>(); 4077 assert(Init && "missing initializer"); 4078 4079 // Capture the variable that is being initialized and the style of 4080 // initialization. 4081 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4082 4083 // FIXME: Poor source location information. 4084 InitializationKind Kind 4085 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4086 Init->getLocStart(), 4087 Init->getLocEnd()) 4088 : InitializationKind::CreateCopy(VDecl->getLocation(), 4089 Init->getLocStart()); 4090 4091 // Get the decls type and save a reference for later, since 4092 // CheckInitializerTypes may change it. 4093 QualType DclT = VDecl->getType(), SavT = DclT; 4094 if (VDecl->isBlockVarDecl()) { 4095 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4096 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4097 VDecl->setInvalidDecl(); 4098 } else if (!VDecl->isInvalidDecl()) { 4099 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4100 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4101 MultiExprArg(*this, (void**)&Init, 1), 4102 &DclT); 4103 if (Result.isInvalid()) { 4104 VDecl->setInvalidDecl(); 4105 return; 4106 } 4107 4108 Init = Result.takeAs<Expr>(); 4109 4110 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4111 // Don't check invalid declarations to avoid emitting useless diagnostics. 4112 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4113 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 4114 CheckForConstantInitializer(Init, DclT); 4115 } 4116 } 4117 } else if (VDecl->isStaticDataMember() && 4118 VDecl->getLexicalDeclContext()->isRecord()) { 4119 // This is an in-class initialization for a static data member, e.g., 4120 // 4121 // struct S { 4122 // static const int value = 17; 4123 // }; 4124 4125 // Attach the initializer 4126 VDecl->setInit(Init); 4127 4128 // C++ [class.mem]p4: 4129 // A member-declarator can contain a constant-initializer only 4130 // if it declares a static member (9.4) of const integral or 4131 // const enumeration type, see 9.4.2. 4132 QualType T = VDecl->getType(); 4133 if (!T->isDependentType() && 4134 (!Context.getCanonicalType(T).isConstQualified() || 4135 !T->isIntegralOrEnumerationType())) { 4136 Diag(VDecl->getLocation(), diag::err_member_initialization) 4137 << VDecl->getDeclName() << Init->getSourceRange(); 4138 VDecl->setInvalidDecl(); 4139 } else { 4140 // C++ [class.static.data]p4: 4141 // If a static data member is of const integral or const 4142 // enumeration type, its declaration in the class definition 4143 // can specify a constant-initializer which shall be an 4144 // integral constant expression (5.19). 4145 if (!Init->isTypeDependent() && 4146 !Init->getType()->isIntegralOrEnumerationType()) { 4147 // We have a non-dependent, non-integral or enumeration type. 4148 Diag(Init->getSourceRange().getBegin(), 4149 diag::err_in_class_initializer_non_integral_type) 4150 << Init->getType() << Init->getSourceRange(); 4151 VDecl->setInvalidDecl(); 4152 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4153 // Check whether the expression is a constant expression. 4154 llvm::APSInt Value; 4155 SourceLocation Loc; 4156 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4157 Diag(Loc, diag::err_in_class_initializer_non_constant) 4158 << Init->getSourceRange(); 4159 VDecl->setInvalidDecl(); 4160 } else if (!VDecl->getType()->isDependentType()) 4161 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4162 } 4163 } 4164 } else if (VDecl->isFileVarDecl()) { 4165 if (VDecl->getStorageClass() == VarDecl::Extern && 4166 (!getLangOptions().CPlusPlus || 4167 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4168 Diag(VDecl->getLocation(), diag::warn_extern_init); 4169 if (!VDecl->isInvalidDecl()) { 4170 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4171 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4172 MultiExprArg(*this, (void**)&Init, 1), 4173 &DclT); 4174 if (Result.isInvalid()) { 4175 VDecl->setInvalidDecl(); 4176 return; 4177 } 4178 4179 Init = Result.takeAs<Expr>(); 4180 } 4181 4182 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4183 // Don't check invalid declarations to avoid emitting useless diagnostics. 4184 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4185 // C99 6.7.8p4. All file scoped initializers need to be constant. 4186 CheckForConstantInitializer(Init, DclT); 4187 } 4188 } 4189 // If the type changed, it means we had an incomplete type that was 4190 // completed by the initializer. For example: 4191 // int ary[] = { 1, 3, 5 }; 4192 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4193 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4194 VDecl->setType(DclT); 4195 Init->setType(DclT); 4196 } 4197 4198 Init = MaybeCreateCXXExprWithTemporaries(Init); 4199 // Attach the initializer to the decl. 4200 VDecl->setInit(Init); 4201 4202 if (getLangOptions().CPlusPlus) { 4203 if (!VDecl->isInvalidDecl() && 4204 !VDecl->getDeclContext()->isDependentContext() && 4205 VDecl->hasGlobalStorage() && 4206 !Init->isConstantInitializer(Context, 4207 VDecl->getType()->isReferenceType())) 4208 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4209 << Init->getSourceRange(); 4210 4211 // Make sure we mark the destructor as used if necessary. 4212 QualType InitType = VDecl->getType(); 4213 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4214 InitType = Context.getBaseElementType(Array); 4215 if (const RecordType *Record = InitType->getAs<RecordType>()) 4216 FinalizeVarWithDestructor(VDecl, Record); 4217 } 4218 4219 return; 4220} 4221 4222/// ActOnInitializerError - Given that there was an error parsing an 4223/// initializer for the given declaration, try to return to some form 4224/// of sanity. 4225void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4226 // Our main concern here is re-establishing invariants like "a 4227 // variable's type is either dependent or complete". 4228 Decl *D = dcl.getAs<Decl>(); 4229 if (!D || D->isInvalidDecl()) return; 4230 4231 VarDecl *VD = dyn_cast<VarDecl>(D); 4232 if (!VD) return; 4233 4234 QualType Ty = VD->getType(); 4235 if (Ty->isDependentType()) return; 4236 4237 // Require a complete type. 4238 if (RequireCompleteType(VD->getLocation(), 4239 Context.getBaseElementType(Ty), 4240 diag::err_typecheck_decl_incomplete_type)) { 4241 VD->setInvalidDecl(); 4242 return; 4243 } 4244 4245 // Require an abstract type. 4246 if (RequireNonAbstractType(VD->getLocation(), Ty, 4247 diag::err_abstract_type_in_decl, 4248 AbstractVariableType)) { 4249 VD->setInvalidDecl(); 4250 return; 4251 } 4252 4253 // Don't bother complaining about constructors or destructors, 4254 // though. 4255} 4256 4257void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4258 bool TypeContainsUndeducedAuto) { 4259 Decl *RealDecl = dcl.getAs<Decl>(); 4260 4261 // If there is no declaration, there was an error parsing it. Just ignore it. 4262 if (RealDecl == 0) 4263 return; 4264 4265 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4266 QualType Type = Var->getType(); 4267 4268 // C++0x [dcl.spec.auto]p3 4269 if (TypeContainsUndeducedAuto) { 4270 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4271 << Var->getDeclName() << Type; 4272 Var->setInvalidDecl(); 4273 return; 4274 } 4275 4276 switch (Var->isThisDeclarationADefinition()) { 4277 case VarDecl::Definition: 4278 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4279 break; 4280 4281 // We have an out-of-line definition of a static data member 4282 // that has an in-class initializer, so we type-check this like 4283 // a declaration. 4284 // 4285 // Fall through 4286 4287 case VarDecl::DeclarationOnly: 4288 // It's only a declaration. 4289 4290 // Block scope. C99 6.7p7: If an identifier for an object is 4291 // declared with no linkage (C99 6.2.2p6), the type for the 4292 // object shall be complete. 4293 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4294 !Var->getLinkage() && !Var->isInvalidDecl() && 4295 RequireCompleteType(Var->getLocation(), Type, 4296 diag::err_typecheck_decl_incomplete_type)) 4297 Var->setInvalidDecl(); 4298 4299 // Make sure that the type is not abstract. 4300 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4301 RequireNonAbstractType(Var->getLocation(), Type, 4302 diag::err_abstract_type_in_decl, 4303 AbstractVariableType)) 4304 Var->setInvalidDecl(); 4305 return; 4306 4307 case VarDecl::TentativeDefinition: 4308 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4309 // object that has file scope without an initializer, and without a 4310 // storage-class specifier or with the storage-class specifier "static", 4311 // constitutes a tentative definition. Note: A tentative definition with 4312 // external linkage is valid (C99 6.2.2p5). 4313 if (!Var->isInvalidDecl()) { 4314 if (const IncompleteArrayType *ArrayT 4315 = Context.getAsIncompleteArrayType(Type)) { 4316 if (RequireCompleteType(Var->getLocation(), 4317 ArrayT->getElementType(), 4318 diag::err_illegal_decl_array_incomplete_type)) 4319 Var->setInvalidDecl(); 4320 } else if (Var->getStorageClass() == VarDecl::Static) { 4321 // C99 6.9.2p3: If the declaration of an identifier for an object is 4322 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4323 // declared type shall not be an incomplete type. 4324 // NOTE: code such as the following 4325 // static struct s; 4326 // struct s { int a; }; 4327 // is accepted by gcc. Hence here we issue a warning instead of 4328 // an error and we do not invalidate the static declaration. 4329 // NOTE: to avoid multiple warnings, only check the first declaration. 4330 if (Var->getPreviousDeclaration() == 0) 4331 RequireCompleteType(Var->getLocation(), Type, 4332 diag::ext_typecheck_decl_incomplete_type); 4333 } 4334 } 4335 4336 // Record the tentative definition; we're done. 4337 if (!Var->isInvalidDecl()) 4338 TentativeDefinitions.push_back(Var); 4339 return; 4340 } 4341 4342 // Provide a specific diagnostic for uninitialized variable 4343 // definitions with incomplete array type. 4344 if (Type->isIncompleteArrayType()) { 4345 Diag(Var->getLocation(), 4346 diag::err_typecheck_incomplete_array_needs_initializer); 4347 Var->setInvalidDecl(); 4348 return; 4349 } 4350 4351 // Provide a specific diagnostic for uninitialized variable 4352 // definitions with reference type. 4353 if (Type->isReferenceType()) { 4354 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4355 << Var->getDeclName() 4356 << SourceRange(Var->getLocation(), Var->getLocation()); 4357 Var->setInvalidDecl(); 4358 return; 4359 } 4360 4361 // Do not attempt to type-check the default initializer for a 4362 // variable with dependent type. 4363 if (Type->isDependentType()) 4364 return; 4365 4366 if (Var->isInvalidDecl()) 4367 return; 4368 4369 if (RequireCompleteType(Var->getLocation(), 4370 Context.getBaseElementType(Type), 4371 diag::err_typecheck_decl_incomplete_type)) { 4372 Var->setInvalidDecl(); 4373 return; 4374 } 4375 4376 // The variable can not have an abstract class type. 4377 if (RequireNonAbstractType(Var->getLocation(), Type, 4378 diag::err_abstract_type_in_decl, 4379 AbstractVariableType)) { 4380 Var->setInvalidDecl(); 4381 return; 4382 } 4383 4384 const RecordType *Record 4385 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4386 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4387 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4388 // C++03 [dcl.init]p9: 4389 // If no initializer is specified for an object, and the 4390 // object is of (possibly cv-qualified) non-POD class type (or 4391 // array thereof), the object shall be default-initialized; if 4392 // the object is of const-qualified type, the underlying class 4393 // type shall have a user-declared default 4394 // constructor. Otherwise, if no initializer is specified for 4395 // a non- static object, the object and its subobjects, if 4396 // any, have an indeterminate initial value); if the object 4397 // or any of its subobjects are of const-qualified type, the 4398 // program is ill-formed. 4399 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4400 } else { 4401 // Check for jumps past the implicit initializer. C++0x 4402 // clarifies that this applies to a "variable with automatic 4403 // storage duration", not a "local variable". 4404 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4405 setFunctionHasBranchProtectedScope(); 4406 4407 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4408 InitializationKind Kind 4409 = InitializationKind::CreateDefault(Var->getLocation()); 4410 4411 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4412 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4413 MultiExprArg(*this, 0, 0)); 4414 if (Init.isInvalid()) 4415 Var->setInvalidDecl(); 4416 else if (Init.get()) { 4417 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4418 4419 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4420 Var->hasGlobalStorage() && 4421 !Var->getDeclContext()->isDependentContext() && 4422 !Var->getInit()->isConstantInitializer(Context, false)) 4423 Diag(Var->getLocation(), diag::warn_global_constructor); 4424 } 4425 } 4426 4427 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4428 FinalizeVarWithDestructor(Var, Record); 4429 } 4430} 4431 4432Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4433 DeclPtrTy *Group, 4434 unsigned NumDecls) { 4435 llvm::SmallVector<Decl*, 8> Decls; 4436 4437 if (DS.isTypeSpecOwned()) 4438 Decls.push_back((Decl*)DS.getTypeRep()); 4439 4440 for (unsigned i = 0; i != NumDecls; ++i) 4441 if (Decl *D = Group[i].getAs<Decl>()) 4442 Decls.push_back(D); 4443 4444 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4445 Decls.data(), Decls.size())); 4446} 4447 4448 4449/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4450/// to introduce parameters into function prototype scope. 4451Sema::DeclPtrTy 4452Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4453 const DeclSpec &DS = D.getDeclSpec(); 4454 4455 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4456 VarDecl::StorageClass StorageClass = VarDecl::None; 4457 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4458 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4459 StorageClass = VarDecl::Register; 4460 StorageClassAsWritten = VarDecl::Register; 4461 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4462 Diag(DS.getStorageClassSpecLoc(), 4463 diag::err_invalid_storage_class_in_func_decl); 4464 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4465 } 4466 4467 if (D.getDeclSpec().isThreadSpecified()) 4468 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4469 4470 DiagnoseFunctionSpecifiers(D); 4471 4472 // Check that there are no default arguments inside the type of this 4473 // parameter (C++ only). 4474 if (getLangOptions().CPlusPlus) 4475 CheckExtraCXXDefaultArguments(D); 4476 4477 TagDecl *OwnedDecl = 0; 4478 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4479 QualType parmDeclType = TInfo->getType(); 4480 4481 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4482 // C++ [dcl.fct]p6: 4483 // Types shall not be defined in return or parameter types. 4484 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4485 << Context.getTypeDeclType(OwnedDecl); 4486 } 4487 4488 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4489 IdentifierInfo *II = D.getIdentifier(); 4490 if (II) { 4491 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4492 ForRedeclaration); 4493 LookupName(R, S); 4494 if (R.isSingleResult()) { 4495 NamedDecl *PrevDecl = R.getFoundDecl(); 4496 if (PrevDecl->isTemplateParameter()) { 4497 // Maybe we will complain about the shadowed template parameter. 4498 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4499 // Just pretend that we didn't see the previous declaration. 4500 PrevDecl = 0; 4501 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4502 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4503 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4504 4505 // Recover by removing the name 4506 II = 0; 4507 D.SetIdentifier(0, D.getIdentifierLoc()); 4508 D.setInvalidType(true); 4509 } 4510 } 4511 } 4512 4513 // Temporarily put parameter variables in the translation unit, not 4514 // the enclosing context. This prevents them from accidentally 4515 // looking like class members in C++. 4516 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4517 TInfo, parmDeclType, II, 4518 D.getIdentifierLoc(), 4519 StorageClass, StorageClassAsWritten); 4520 4521 if (D.isInvalidType()) 4522 New->setInvalidDecl(); 4523 4524 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4525 if (D.getCXXScopeSpec().isSet()) { 4526 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4527 << D.getCXXScopeSpec().getRange(); 4528 New->setInvalidDecl(); 4529 } 4530 4531 // Add the parameter declaration into this scope. 4532 S->AddDecl(DeclPtrTy::make(New)); 4533 if (II) 4534 IdResolver.AddDecl(New); 4535 4536 ProcessDeclAttributes(S, New, D); 4537 4538 if (New->hasAttr<BlocksAttr>()) { 4539 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4540 } 4541 return DeclPtrTy::make(New); 4542} 4543 4544/// \brief Synthesizes a variable for a parameter arising from a 4545/// typedef. 4546ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4547 SourceLocation Loc, 4548 QualType T) { 4549 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4550 T, Context.getTrivialTypeSourceInfo(T, Loc), 4551 VarDecl::None, VarDecl::None, 0); 4552 Param->setImplicit(); 4553 return Param; 4554} 4555 4556ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4557 TypeSourceInfo *TSInfo, QualType T, 4558 IdentifierInfo *Name, 4559 SourceLocation NameLoc, 4560 VarDecl::StorageClass StorageClass, 4561 VarDecl::StorageClass StorageClassAsWritten) { 4562 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4563 adjustParameterType(T), TSInfo, 4564 StorageClass, StorageClassAsWritten, 4565 0); 4566 4567 // Parameters can not be abstract class types. 4568 // For record types, this is done by the AbstractClassUsageDiagnoser once 4569 // the class has been completely parsed. 4570 if (!CurContext->isRecord() && 4571 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4572 AbstractParamType)) 4573 New->setInvalidDecl(); 4574 4575 // Parameter declarators cannot be interface types. All ObjC objects are 4576 // passed by reference. 4577 if (T->isObjCObjectType()) { 4578 Diag(NameLoc, 4579 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4580 New->setInvalidDecl(); 4581 } 4582 4583 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4584 // duration shall not be qualified by an address-space qualifier." 4585 // Since all parameters have automatic store duration, they can not have 4586 // an address space. 4587 if (T.getAddressSpace() != 0) { 4588 Diag(NameLoc, diag::err_arg_with_address_space); 4589 New->setInvalidDecl(); 4590 } 4591 4592 return New; 4593} 4594 4595void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4596 SourceLocation LocAfterDecls) { 4597 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4598 "Not a function declarator!"); 4599 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4600 4601 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4602 // for a K&R function. 4603 if (!FTI.hasPrototype) { 4604 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4605 --i; 4606 if (FTI.ArgInfo[i].Param == 0) { 4607 llvm::SmallString<256> Code; 4608 llvm::raw_svector_ostream(Code) << " int " 4609 << FTI.ArgInfo[i].Ident->getName() 4610 << ";\n"; 4611 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4612 << FTI.ArgInfo[i].Ident 4613 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4614 4615 // Implicitly declare the argument as type 'int' for lack of a better 4616 // type. 4617 DeclSpec DS; 4618 const char* PrevSpec; // unused 4619 unsigned DiagID; // unused 4620 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4621 PrevSpec, DiagID); 4622 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4623 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4624 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4625 } 4626 } 4627 } 4628} 4629 4630Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4631 Declarator &D) { 4632 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4633 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4634 "Not a function declarator!"); 4635 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4636 4637 if (FTI.hasPrototype) { 4638 // FIXME: Diagnose arguments without names in C. 4639 } 4640 4641 Scope *ParentScope = FnBodyScope->getParent(); 4642 4643 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4644 MultiTemplateParamsArg(*this), 4645 /*IsFunctionDefinition=*/true); 4646 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4647} 4648 4649static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4650 // Don't warn about invalid declarations. 4651 if (FD->isInvalidDecl()) 4652 return false; 4653 4654 // Or declarations that aren't global. 4655 if (!FD->isGlobal()) 4656 return false; 4657 4658 // Don't warn about C++ member functions. 4659 if (isa<CXXMethodDecl>(FD)) 4660 return false; 4661 4662 // Don't warn about 'main'. 4663 if (FD->isMain()) 4664 return false; 4665 4666 // Don't warn about inline functions. 4667 if (FD->isInlineSpecified()) 4668 return false; 4669 4670 // Don't warn about function templates. 4671 if (FD->getDescribedFunctionTemplate()) 4672 return false; 4673 4674 // Don't warn about function template specializations. 4675 if (FD->isFunctionTemplateSpecialization()) 4676 return false; 4677 4678 bool MissingPrototype = true; 4679 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4680 Prev; Prev = Prev->getPreviousDeclaration()) { 4681 // Ignore any declarations that occur in function or method 4682 // scope, because they aren't visible from the header. 4683 if (Prev->getDeclContext()->isFunctionOrMethod()) 4684 continue; 4685 4686 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4687 break; 4688 } 4689 4690 return MissingPrototype; 4691} 4692 4693Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4694 // Clear the last template instantiation error context. 4695 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4696 4697 if (!D) 4698 return D; 4699 FunctionDecl *FD = 0; 4700 4701 if (FunctionTemplateDecl *FunTmpl 4702 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4703 FD = FunTmpl->getTemplatedDecl(); 4704 else 4705 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4706 4707 // Enter a new function scope 4708 PushFunctionScope(); 4709 4710 // See if this is a redefinition. 4711 // But don't complain if we're in GNU89 mode and the previous definition 4712 // was an extern inline function. 4713 const FunctionDecl *Definition; 4714 if (FD->hasBody(Definition) && 4715 !canRedefineFunction(Definition, getLangOptions())) { 4716 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4717 Diag(Definition->getLocation(), diag::note_previous_definition); 4718 } 4719 4720 // Builtin functions cannot be defined. 4721 if (unsigned BuiltinID = FD->getBuiltinID()) { 4722 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4723 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4724 FD->setInvalidDecl(); 4725 } 4726 } 4727 4728 // The return type of a function definition must be complete 4729 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4730 QualType ResultType = FD->getResultType(); 4731 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4732 !FD->isInvalidDecl() && 4733 RequireCompleteType(FD->getLocation(), ResultType, 4734 diag::err_func_def_incomplete_result)) 4735 FD->setInvalidDecl(); 4736 4737 // GNU warning -Wmissing-prototypes: 4738 // Warn if a global function is defined without a previous 4739 // prototype declaration. This warning is issued even if the 4740 // definition itself provides a prototype. The aim is to detect 4741 // global functions that fail to be declared in header files. 4742 if (ShouldWarnAboutMissingPrototype(FD)) 4743 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4744 4745 if (FnBodyScope) 4746 PushDeclContext(FnBodyScope, FD); 4747 4748 // Check the validity of our function parameters 4749 CheckParmsForFunctionDef(FD); 4750 4751 bool ShouldCheckShadow = 4752 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4753 4754 // Introduce our parameters into the function scope 4755 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4756 ParmVarDecl *Param = FD->getParamDecl(p); 4757 Param->setOwningFunction(FD); 4758 4759 // If this has an identifier, add it to the scope stack. 4760 if (Param->getIdentifier() && FnBodyScope) { 4761 if (ShouldCheckShadow) 4762 CheckShadow(FnBodyScope, Param); 4763 4764 PushOnScopeChains(Param, FnBodyScope); 4765 } 4766 } 4767 4768 // Checking attributes of current function definition 4769 // dllimport attribute. 4770 if (FD->getAttr<DLLImportAttr>() && 4771 (!FD->getAttr<DLLExportAttr>())) { 4772 // dllimport attribute cannot be applied to definition. 4773 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4774 Diag(FD->getLocation(), 4775 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4776 << "dllimport"; 4777 FD->setInvalidDecl(); 4778 return DeclPtrTy::make(FD); 4779 } 4780 4781 // Visual C++ appears to not think this is an issue, so only issue 4782 // a warning when Microsoft extensions are disabled. 4783 if (!LangOpts.Microsoft) { 4784 // If a symbol previously declared dllimport is later defined, the 4785 // attribute is ignored in subsequent references, and a warning is 4786 // emitted. 4787 Diag(FD->getLocation(), 4788 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4789 << FD->getNameAsCString() << "dllimport"; 4790 } 4791 } 4792 return DeclPtrTy::make(FD); 4793} 4794 4795/// \brief Given the set of return statements within a function body, 4796/// compute the variables that are subject to the named return value 4797/// optimization. 4798/// 4799/// Each of the variables that is subject to the named return value 4800/// optimization will be marked as NRVO variables in the AST, and any 4801/// return statement that has a marked NRVO variable as its NRVO candidate can 4802/// use the named return value optimization. 4803/// 4804/// This function applies a very simplistic algorithm for NRVO: if every return 4805/// statement in the function has the same NRVO candidate, that candidate is 4806/// the NRVO variable. 4807/// 4808/// FIXME: Employ a smarter algorithm that accounts for multiple return 4809/// statements and the lifetimes of the NRVO candidates. We should be able to 4810/// find a maximal set of NRVO variables. 4811static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4812 const VarDecl *NRVOCandidate = 0; 4813 for (unsigned I = 0; I != NumReturns; ++I) { 4814 if (!Returns[I]->getNRVOCandidate()) 4815 return; 4816 4817 if (!NRVOCandidate) 4818 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4819 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4820 return; 4821 } 4822 4823 if (NRVOCandidate) 4824 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4825} 4826 4827Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4828 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4829} 4830 4831Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4832 bool IsInstantiation) { 4833 Decl *dcl = D.getAs<Decl>(); 4834 Stmt *Body = BodyArg.takeAs<Stmt>(); 4835 4836 FunctionDecl *FD = 0; 4837 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4838 if (FunTmpl) 4839 FD = FunTmpl->getTemplatedDecl(); 4840 else 4841 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4842 4843 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4844 4845 if (FD) { 4846 FD->setBody(Body); 4847 if (FD->isMain()) { 4848 // C and C++ allow for main to automagically return 0. 4849 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4850 FD->setHasImplicitReturnZero(true); 4851 WP.disableCheckFallThrough(); 4852 } 4853 4854 if (!FD->isInvalidDecl()) { 4855 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4856 4857 // If this is a constructor, we need a vtable. 4858 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4859 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4860 4861 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4862 FunctionScopes.back()->Returns.size()); 4863 } 4864 4865 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4866 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4867 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4868 MD->setBody(Body); 4869 MD->setEndLoc(Body->getLocEnd()); 4870 if (!MD->isInvalidDecl()) 4871 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4872 } else { 4873 return DeclPtrTy(); 4874 } 4875 4876 // Verify and clean out per-function state. 4877 4878 // Check goto/label use. 4879 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4880 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4881 LabelStmt *L = I->second; 4882 4883 // Verify that we have no forward references left. If so, there was a goto 4884 // or address of a label taken, but no definition of it. Label fwd 4885 // definitions are indicated with a null substmt. 4886 if (L->getSubStmt() != 0) 4887 continue; 4888 4889 // Emit error. 4890 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4891 4892 // At this point, we have gotos that use the bogus label. Stitch it into 4893 // the function body so that they aren't leaked and that the AST is well 4894 // formed. 4895 if (Body == 0) { 4896 // The whole function wasn't parsed correctly. 4897 continue; 4898 } 4899 4900 // Otherwise, the body is valid: we want to stitch the label decl into the 4901 // function somewhere so that it is properly owned and so that the goto 4902 // has a valid target. Do this by creating a new compound stmt with the 4903 // label in it. 4904 4905 // Give the label a sub-statement. 4906 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4907 4908 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4909 cast<CXXTryStmt>(Body)->getTryBlock() : 4910 cast<CompoundStmt>(Body); 4911 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4912 Compound->body_end()); 4913 Elements.push_back(L); 4914 Compound->setStmts(Context, Elements.data(), Elements.size()); 4915 } 4916 4917 if (Body) { 4918 // C++ constructors that have function-try-blocks can't have return 4919 // statements in the handlers of that block. (C++ [except.handle]p14) 4920 // Verify this. 4921 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4922 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4923 4924 // Verify that that gotos and switch cases don't jump into scopes illegally. 4925 // Verify that that gotos and switch cases don't jump into scopes illegally. 4926 if (FunctionNeedsScopeChecking() && 4927 !dcl->isInvalidDecl() && 4928 !hasAnyErrorsInThisFunction()) 4929 DiagnoseInvalidJumps(Body); 4930 4931 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 4932 if (!Destructor->getParent()->isDependentType()) 4933 CheckDestructor(Destructor); 4934 4935 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4936 Destructor->getParent()); 4937 } 4938 4939 // If any errors have occurred, clear out any temporaries that may have 4940 // been leftover. This ensures that these temporaries won't be picked up for 4941 // deletion in some later function. 4942 if (PP.getDiagnostics().hasErrorOccurred()) 4943 ExprTemporaries.clear(); 4944 else if (!isa<FunctionTemplateDecl>(dcl)) { 4945 // Since the body is valid, issue any analysis-based warnings that are 4946 // enabled. 4947 QualType ResultType; 4948 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4949 ResultType = FD->getResultType(); 4950 } 4951 else { 4952 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4953 ResultType = MD->getResultType(); 4954 } 4955 AnalysisWarnings.IssueWarnings(WP, dcl); 4956 } 4957 4958 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4959 } 4960 4961 if (!IsInstantiation) 4962 PopDeclContext(); 4963 4964 PopFunctionOrBlockScope(); 4965 4966 // If any errors have occurred, clear out any temporaries that may have 4967 // been leftover. This ensures that these temporaries won't be picked up for 4968 // deletion in some later function. 4969 if (getDiagnostics().hasErrorOccurred()) 4970 ExprTemporaries.clear(); 4971 4972 return D; 4973} 4974 4975/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4976/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4977NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4978 IdentifierInfo &II, Scope *S) { 4979 // Before we produce a declaration for an implicitly defined 4980 // function, see whether there was a locally-scoped declaration of 4981 // this name as a function or variable. If so, use that 4982 // (non-visible) declaration, and complain about it. 4983 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4984 = LocallyScopedExternalDecls.find(&II); 4985 if (Pos != LocallyScopedExternalDecls.end()) { 4986 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4987 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4988 return Pos->second; 4989 } 4990 4991 // Extension in C99. Legal in C90, but warn about it. 4992 if (II.getName().startswith("__builtin_")) 4993 Diag(Loc, diag::warn_builtin_unknown) << &II; 4994 else if (getLangOptions().C99) 4995 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4996 else 4997 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4998 4999 // Set a Declarator for the implicit definition: int foo(); 5000 const char *Dummy; 5001 DeclSpec DS; 5002 unsigned DiagID; 5003 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5004 Error = Error; // Silence warning. 5005 assert(!Error && "Error setting up implicit decl!"); 5006 Declarator D(DS, Declarator::BlockContext); 5007 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5008 0, 0, false, SourceLocation(), 5009 false, 0,0,0, Loc, Loc, D), 5010 SourceLocation()); 5011 D.SetIdentifier(&II, Loc); 5012 5013 // Insert this function into translation-unit scope. 5014 5015 DeclContext *PrevDC = CurContext; 5016 CurContext = Context.getTranslationUnitDecl(); 5017 5018 FunctionDecl *FD = 5019 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 5020 FD->setImplicit(); 5021 5022 CurContext = PrevDC; 5023 5024 AddKnownFunctionAttributes(FD); 5025 5026 return FD; 5027} 5028 5029/// \brief Adds any function attributes that we know a priori based on 5030/// the declaration of this function. 5031/// 5032/// These attributes can apply both to implicitly-declared builtins 5033/// (like __builtin___printf_chk) or to library-declared functions 5034/// like NSLog or printf. 5035void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5036 if (FD->isInvalidDecl()) 5037 return; 5038 5039 // If this is a built-in function, map its builtin attributes to 5040 // actual attributes. 5041 if (unsigned BuiltinID = FD->getBuiltinID()) { 5042 // Handle printf-formatting attributes. 5043 unsigned FormatIdx; 5044 bool HasVAListArg; 5045 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5046 if (!FD->getAttr<FormatAttr>()) 5047 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 5048 HasVAListArg ? 0 : FormatIdx+2)); 5049 } 5050 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5051 HasVAListArg)) { 5052 if (!FD->getAttr<FormatAttr>()) 5053 FD->addAttr(::new (Context) FormatAttr(Context, "scanf", FormatIdx+1, 5054 HasVAListArg ? 0 : FormatIdx+2)); 5055 } 5056 5057 // Mark const if we don't care about errno and that is the only 5058 // thing preventing the function from being const. This allows 5059 // IRgen to use LLVM intrinsics for such functions. 5060 if (!getLangOptions().MathErrno && 5061 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5062 if (!FD->getAttr<ConstAttr>()) 5063 FD->addAttr(::new (Context) ConstAttr()); 5064 } 5065 5066 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5067 FD->setType(Context.getNoReturnType(FD->getType())); 5068 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5069 FD->addAttr(::new (Context) NoThrowAttr()); 5070 if (Context.BuiltinInfo.isConst(BuiltinID)) 5071 FD->addAttr(::new (Context) ConstAttr()); 5072 } 5073 5074 IdentifierInfo *Name = FD->getIdentifier(); 5075 if (!Name) 5076 return; 5077 if ((!getLangOptions().CPlusPlus && 5078 FD->getDeclContext()->isTranslationUnit()) || 5079 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5080 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5081 LinkageSpecDecl::lang_c)) { 5082 // Okay: this could be a libc/libm/Objective-C function we know 5083 // about. 5084 } else 5085 return; 5086 5087 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5088 // FIXME: NSLog and NSLogv should be target specific 5089 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5090 // FIXME: We known better than our headers. 5091 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5092 } else 5093 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 5094 Name->isStr("NSLogv") ? 0 : 2)); 5095 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5096 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5097 // target-specific builtins, perhaps? 5098 if (!FD->getAttr<FormatAttr>()) 5099 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 5100 Name->isStr("vasprintf") ? 0 : 3)); 5101 } 5102} 5103 5104TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5105 TypeSourceInfo *TInfo) { 5106 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5107 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5108 5109 if (!TInfo) { 5110 assert(D.isInvalidType() && "no declarator info for valid type"); 5111 TInfo = Context.getTrivialTypeSourceInfo(T); 5112 } 5113 5114 // Scope manipulation handled by caller. 5115 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5116 D.getIdentifierLoc(), 5117 D.getIdentifier(), 5118 TInfo); 5119 5120 if (const TagType *TT = T->getAs<TagType>()) { 5121 TagDecl *TD = TT->getDecl(); 5122 5123 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5124 // keep track of the TypedefDecl. 5125 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5126 TD->setTypedefForAnonDecl(NewTD); 5127 } 5128 5129 if (D.isInvalidType()) 5130 NewTD->setInvalidDecl(); 5131 return NewTD; 5132} 5133 5134 5135/// \brief Determine whether a tag with a given kind is acceptable 5136/// as a redeclaration of the given tag declaration. 5137/// 5138/// \returns true if the new tag kind is acceptable, false otherwise. 5139bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5140 TagTypeKind NewTag, 5141 SourceLocation NewTagLoc, 5142 const IdentifierInfo &Name) { 5143 // C++ [dcl.type.elab]p3: 5144 // The class-key or enum keyword present in the 5145 // elaborated-type-specifier shall agree in kind with the 5146 // declaration to which the name in the elaborated-type-specifier 5147 // refers. This rule also applies to the form of 5148 // elaborated-type-specifier that declares a class-name or 5149 // friend class since it can be construed as referring to the 5150 // definition of the class. Thus, in any 5151 // elaborated-type-specifier, the enum keyword shall be used to 5152 // refer to an enumeration (7.2), the union class-key shall be 5153 // used to refer to a union (clause 9), and either the class or 5154 // struct class-key shall be used to refer to a class (clause 9) 5155 // declared using the class or struct class-key. 5156 TagTypeKind OldTag = Previous->getTagKind(); 5157 if (OldTag == NewTag) 5158 return true; 5159 5160 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5161 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5162 // Warn about the struct/class tag mismatch. 5163 bool isTemplate = false; 5164 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5165 isTemplate = Record->getDescribedClassTemplate(); 5166 5167 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5168 << (NewTag == TTK_Class) 5169 << isTemplate << &Name 5170 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5171 OldTag == TTK_Class? "class" : "struct"); 5172 Diag(Previous->getLocation(), diag::note_previous_use); 5173 return true; 5174 } 5175 return false; 5176} 5177 5178/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5179/// former case, Name will be non-null. In the later case, Name will be null. 5180/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5181/// reference/declaration/definition of a tag. 5182Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5183 SourceLocation KWLoc, CXXScopeSpec &SS, 5184 IdentifierInfo *Name, SourceLocation NameLoc, 5185 AttributeList *Attr, AccessSpecifier AS, 5186 MultiTemplateParamsArg TemplateParameterLists, 5187 bool &OwnedDecl, bool &IsDependent) { 5188 // If this is not a definition, it must have a name. 5189 assert((Name != 0 || TUK == TUK_Definition) && 5190 "Nameless record must be a definition!"); 5191 5192 OwnedDecl = false; 5193 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5194 5195 // FIXME: Check explicit specializations more carefully. 5196 bool isExplicitSpecialization = false; 5197 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5198 bool Invalid = false; 5199 if (TUK != TUK_Reference) { 5200 if (TemplateParameterList *TemplateParams 5201 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5202 (TemplateParameterList**)TemplateParameterLists.get(), 5203 TemplateParameterLists.size(), 5204 TUK == TUK_Friend, 5205 isExplicitSpecialization, 5206 Invalid)) { 5207 // All but one template parameter lists have been matching. 5208 --NumMatchedTemplateParamLists; 5209 5210 if (TemplateParams->size() > 0) { 5211 // This is a declaration or definition of a class template (which may 5212 // be a member of another template). 5213 if (Invalid) 5214 return DeclPtrTy(); 5215 5216 OwnedDecl = false; 5217 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5218 SS, Name, NameLoc, Attr, 5219 TemplateParams, 5220 AS); 5221 TemplateParameterLists.release(); 5222 return Result.get(); 5223 } else { 5224 // The "template<>" header is extraneous. 5225 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5226 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5227 isExplicitSpecialization = true; 5228 } 5229 } 5230 } 5231 5232 DeclContext *SearchDC = CurContext; 5233 DeclContext *DC = CurContext; 5234 bool isStdBadAlloc = false; 5235 5236 RedeclarationKind Redecl = ForRedeclaration; 5237 if (TUK == TUK_Friend || TUK == TUK_Reference) 5238 Redecl = NotForRedeclaration; 5239 5240 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5241 5242 if (Name && SS.isNotEmpty()) { 5243 // We have a nested-name tag ('struct foo::bar'). 5244 5245 // Check for invalid 'foo::'. 5246 if (SS.isInvalid()) { 5247 Name = 0; 5248 goto CreateNewDecl; 5249 } 5250 5251 // If this is a friend or a reference to a class in a dependent 5252 // context, don't try to make a decl for it. 5253 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5254 DC = computeDeclContext(SS, false); 5255 if (!DC) { 5256 IsDependent = true; 5257 return DeclPtrTy(); 5258 } 5259 } else { 5260 DC = computeDeclContext(SS, true); 5261 if (!DC) { 5262 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5263 << SS.getRange(); 5264 return DeclPtrTy(); 5265 } 5266 } 5267 5268 if (RequireCompleteDeclContext(SS, DC)) 5269 return DeclPtrTy::make((Decl *)0); 5270 5271 SearchDC = DC; 5272 // Look-up name inside 'foo::'. 5273 LookupQualifiedName(Previous, DC); 5274 5275 if (Previous.isAmbiguous()) 5276 return DeclPtrTy(); 5277 5278 if (Previous.empty()) { 5279 // Name lookup did not find anything. However, if the 5280 // nested-name-specifier refers to the current instantiation, 5281 // and that current instantiation has any dependent base 5282 // classes, we might find something at instantiation time: treat 5283 // this as a dependent elaborated-type-specifier. 5284 if (Previous.wasNotFoundInCurrentInstantiation()) { 5285 IsDependent = true; 5286 return DeclPtrTy(); 5287 } 5288 5289 // A tag 'foo::bar' must already exist. 5290 Diag(NameLoc, diag::err_not_tag_in_scope) 5291 << Kind << Name << DC << SS.getRange(); 5292 Name = 0; 5293 Invalid = true; 5294 goto CreateNewDecl; 5295 } 5296 } else if (Name) { 5297 // If this is a named struct, check to see if there was a previous forward 5298 // declaration or definition. 5299 // FIXME: We're looking into outer scopes here, even when we 5300 // shouldn't be. Doing so can result in ambiguities that we 5301 // shouldn't be diagnosing. 5302 LookupName(Previous, S); 5303 5304 // Note: there used to be some attempt at recovery here. 5305 if (Previous.isAmbiguous()) 5306 return DeclPtrTy(); 5307 5308 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5309 // FIXME: This makes sure that we ignore the contexts associated 5310 // with C structs, unions, and enums when looking for a matching 5311 // tag declaration or definition. See the similar lookup tweak 5312 // in Sema::LookupName; is there a better way to deal with this? 5313 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5314 SearchDC = SearchDC->getParent(); 5315 } 5316 } 5317 5318 if (Previous.isSingleResult() && 5319 Previous.getFoundDecl()->isTemplateParameter()) { 5320 // Maybe we will complain about the shadowed template parameter. 5321 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5322 // Just pretend that we didn't see the previous declaration. 5323 Previous.clear(); 5324 } 5325 5326 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5327 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5328 // This is a declaration of or a reference to "std::bad_alloc". 5329 isStdBadAlloc = true; 5330 5331 if (Previous.empty() && StdBadAlloc) { 5332 // std::bad_alloc has been implicitly declared (but made invisible to 5333 // name lookup). Fill in this implicit declaration as the previous 5334 // declaration, so that the declarations get chained appropriately. 5335 Previous.addDecl(getStdBadAlloc()); 5336 } 5337 } 5338 5339 // If we didn't find a previous declaration, and this is a reference 5340 // (or friend reference), move to the correct scope. In C++, we 5341 // also need to do a redeclaration lookup there, just in case 5342 // there's a shadow friend decl. 5343 if (Name && Previous.empty() && 5344 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5345 if (Invalid) goto CreateNewDecl; 5346 assert(SS.isEmpty()); 5347 5348 if (TUK == TUK_Reference) { 5349 // C++ [basic.scope.pdecl]p5: 5350 // -- for an elaborated-type-specifier of the form 5351 // 5352 // class-key identifier 5353 // 5354 // if the elaborated-type-specifier is used in the 5355 // decl-specifier-seq or parameter-declaration-clause of a 5356 // function defined in namespace scope, the identifier is 5357 // declared as a class-name in the namespace that contains 5358 // the declaration; otherwise, except as a friend 5359 // declaration, the identifier is declared in the smallest 5360 // non-class, non-function-prototype scope that contains the 5361 // declaration. 5362 // 5363 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5364 // C structs and unions. 5365 // 5366 // It is an error in C++ to declare (rather than define) an enum 5367 // type, including via an elaborated type specifier. We'll 5368 // diagnose that later; for now, declare the enum in the same 5369 // scope as we would have picked for any other tag type. 5370 // 5371 // GNU C also supports this behavior as part of its incomplete 5372 // enum types extension, while GNU C++ does not. 5373 // 5374 // Find the context where we'll be declaring the tag. 5375 // FIXME: We would like to maintain the current DeclContext as the 5376 // lexical context, 5377 while (SearchDC->isRecord()) 5378 SearchDC = SearchDC->getParent(); 5379 5380 // Find the scope where we'll be declaring the tag. 5381 while (S->isClassScope() || 5382 (getLangOptions().CPlusPlus && 5383 S->isFunctionPrototypeScope()) || 5384 ((S->getFlags() & Scope::DeclScope) == 0) || 5385 (S->getEntity() && 5386 ((DeclContext *)S->getEntity())->isTransparentContext())) 5387 S = S->getParent(); 5388 } else { 5389 assert(TUK == TUK_Friend); 5390 // C++ [namespace.memdef]p3: 5391 // If a friend declaration in a non-local class first declares a 5392 // class or function, the friend class or function is a member of 5393 // the innermost enclosing namespace. 5394 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5395 } 5396 5397 // In C++, we need to do a redeclaration lookup to properly 5398 // diagnose some problems. 5399 if (getLangOptions().CPlusPlus) { 5400 Previous.setRedeclarationKind(ForRedeclaration); 5401 LookupQualifiedName(Previous, SearchDC); 5402 } 5403 } 5404 5405 if (!Previous.empty()) { 5406 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5407 5408 // It's okay to have a tag decl in the same scope as a typedef 5409 // which hides a tag decl in the same scope. Finding this 5410 // insanity with a redeclaration lookup can only actually happen 5411 // in C++. 5412 // 5413 // This is also okay for elaborated-type-specifiers, which is 5414 // technically forbidden by the current standard but which is 5415 // okay according to the likely resolution of an open issue; 5416 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5417 if (getLangOptions().CPlusPlus) { 5418 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5419 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5420 TagDecl *Tag = TT->getDecl(); 5421 if (Tag->getDeclName() == Name && 5422 Tag->getDeclContext()->getLookupContext() 5423 ->Equals(TD->getDeclContext()->getLookupContext())) { 5424 PrevDecl = Tag; 5425 Previous.clear(); 5426 Previous.addDecl(Tag); 5427 } 5428 } 5429 } 5430 } 5431 5432 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5433 // If this is a use of a previous tag, or if the tag is already declared 5434 // in the same scope (so that the definition/declaration completes or 5435 // rementions the tag), reuse the decl. 5436 if (TUK == TUK_Reference || TUK == TUK_Friend || 5437 isDeclInScope(PrevDecl, SearchDC, S)) { 5438 // Make sure that this wasn't declared as an enum and now used as a 5439 // struct or something similar. 5440 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5441 bool SafeToContinue 5442 = (PrevTagDecl->getTagKind() != TTK_Enum && 5443 Kind != TTK_Enum); 5444 if (SafeToContinue) 5445 Diag(KWLoc, diag::err_use_with_wrong_tag) 5446 << Name 5447 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5448 PrevTagDecl->getKindName()); 5449 else 5450 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5451 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5452 5453 if (SafeToContinue) 5454 Kind = PrevTagDecl->getTagKind(); 5455 else { 5456 // Recover by making this an anonymous redefinition. 5457 Name = 0; 5458 Previous.clear(); 5459 Invalid = true; 5460 } 5461 } 5462 5463 if (!Invalid) { 5464 // If this is a use, just return the declaration we found. 5465 5466 // FIXME: In the future, return a variant or some other clue 5467 // for the consumer of this Decl to know it doesn't own it. 5468 // For our current ASTs this shouldn't be a problem, but will 5469 // need to be changed with DeclGroups. 5470 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5471 TUK == TUK_Friend) 5472 return DeclPtrTy::make(PrevTagDecl); 5473 5474 // Diagnose attempts to redefine a tag. 5475 if (TUK == TUK_Definition) { 5476 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5477 // If we're defining a specialization and the previous definition 5478 // is from an implicit instantiation, don't emit an error 5479 // here; we'll catch this in the general case below. 5480 if (!isExplicitSpecialization || 5481 !isa<CXXRecordDecl>(Def) || 5482 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5483 == TSK_ExplicitSpecialization) { 5484 Diag(NameLoc, diag::err_redefinition) << Name; 5485 Diag(Def->getLocation(), diag::note_previous_definition); 5486 // If this is a redefinition, recover by making this 5487 // struct be anonymous, which will make any later 5488 // references get the previous definition. 5489 Name = 0; 5490 Previous.clear(); 5491 Invalid = true; 5492 } 5493 } else { 5494 // If the type is currently being defined, complain 5495 // about a nested redefinition. 5496 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5497 if (Tag->isBeingDefined()) { 5498 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5499 Diag(PrevTagDecl->getLocation(), 5500 diag::note_previous_definition); 5501 Name = 0; 5502 Previous.clear(); 5503 Invalid = true; 5504 } 5505 } 5506 5507 // Okay, this is definition of a previously declared or referenced 5508 // tag PrevDecl. We're going to create a new Decl for it. 5509 } 5510 } 5511 // If we get here we have (another) forward declaration or we 5512 // have a definition. Just create a new decl. 5513 5514 } else { 5515 // If we get here, this is a definition of a new tag type in a nested 5516 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5517 // new decl/type. We set PrevDecl to NULL so that the entities 5518 // have distinct types. 5519 Previous.clear(); 5520 } 5521 // If we get here, we're going to create a new Decl. If PrevDecl 5522 // is non-NULL, it's a definition of the tag declared by 5523 // PrevDecl. If it's NULL, we have a new definition. 5524 5525 5526 // Otherwise, PrevDecl is not a tag, but was found with tag 5527 // lookup. This is only actually possible in C++, where a few 5528 // things like templates still live in the tag namespace. 5529 } else { 5530 assert(getLangOptions().CPlusPlus); 5531 5532 // Use a better diagnostic if an elaborated-type-specifier 5533 // found the wrong kind of type on the first 5534 // (non-redeclaration) lookup. 5535 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5536 !Previous.isForRedeclaration()) { 5537 unsigned Kind = 0; 5538 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5539 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5540 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5541 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5542 Invalid = true; 5543 5544 // Otherwise, only diagnose if the declaration is in scope. 5545 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5546 // do nothing 5547 5548 // Diagnose implicit declarations introduced by elaborated types. 5549 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5550 unsigned Kind = 0; 5551 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5552 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5553 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5554 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5555 Invalid = true; 5556 5557 // Otherwise it's a declaration. Call out a particularly common 5558 // case here. 5559 } else if (isa<TypedefDecl>(PrevDecl)) { 5560 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5561 << Name 5562 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5563 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5564 Invalid = true; 5565 5566 // Otherwise, diagnose. 5567 } else { 5568 // The tag name clashes with something else in the target scope, 5569 // issue an error and recover by making this tag be anonymous. 5570 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5571 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5572 Name = 0; 5573 Invalid = true; 5574 } 5575 5576 // The existing declaration isn't relevant to us; we're in a 5577 // new scope, so clear out the previous declaration. 5578 Previous.clear(); 5579 } 5580 } 5581 5582CreateNewDecl: 5583 5584 TagDecl *PrevDecl = 0; 5585 if (Previous.isSingleResult()) 5586 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5587 5588 // If there is an identifier, use the location of the identifier as the 5589 // location of the decl, otherwise use the location of the struct/union 5590 // keyword. 5591 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5592 5593 // Otherwise, create a new declaration. If there is a previous 5594 // declaration of the same entity, the two will be linked via 5595 // PrevDecl. 5596 TagDecl *New; 5597 5598 if (Kind == TTK_Enum) { 5599 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5600 // enum X { A, B, C } D; D should chain to X. 5601 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5602 cast_or_null<EnumDecl>(PrevDecl)); 5603 // If this is an undefined enum, warn. 5604 if (TUK != TUK_Definition && !Invalid) { 5605 TagDecl *Def; 5606 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5607 Diag(Loc, diag::ext_forward_ref_enum_def) 5608 << New; 5609 Diag(Def->getLocation(), diag::note_previous_definition); 5610 } else { 5611 Diag(Loc, 5612 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5613 : diag::ext_forward_ref_enum); 5614 } 5615 } 5616 } else { 5617 // struct/union/class 5618 5619 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5620 // struct X { int A; } D; D should chain to X. 5621 if (getLangOptions().CPlusPlus) { 5622 // FIXME: Look for a way to use RecordDecl for simple structs. 5623 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5624 cast_or_null<CXXRecordDecl>(PrevDecl)); 5625 5626 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5627 StdBadAlloc = cast<CXXRecordDecl>(New); 5628 } else 5629 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5630 cast_or_null<RecordDecl>(PrevDecl)); 5631 } 5632 5633 // Maybe add qualifier info. 5634 if (SS.isNotEmpty()) { 5635 if (SS.isSet()) { 5636 NestedNameSpecifier *NNS 5637 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5638 New->setQualifierInfo(NNS, SS.getRange()); 5639 if (NumMatchedTemplateParamLists > 0) { 5640 New->setTemplateParameterListsInfo(Context, 5641 NumMatchedTemplateParamLists, 5642 (TemplateParameterList**) TemplateParameterLists.release()); 5643 } 5644 } 5645 else 5646 Invalid = true; 5647 } 5648 5649 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5650 // Add alignment attributes if necessary; these attributes are checked when 5651 // the ASTContext lays out the structure. 5652 // 5653 // It is important for implementing the correct semantics that this 5654 // happen here (in act on tag decl). The #pragma pack stack is 5655 // maintained as a result of parser callbacks which can occur at 5656 // many points during the parsing of a struct declaration (because 5657 // the #pragma tokens are effectively skipped over during the 5658 // parsing of the struct). 5659 AddAlignmentAttributesForRecord(RD); 5660 } 5661 5662 // If this is a specialization of a member class (of a class template), 5663 // check the specialization. 5664 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5665 Invalid = true; 5666 5667 if (Invalid) 5668 New->setInvalidDecl(); 5669 5670 if (Attr) 5671 ProcessDeclAttributeList(S, New, Attr); 5672 5673 // If we're declaring or defining a tag in function prototype scope 5674 // in C, note that this type can only be used within the function. 5675 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5676 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5677 5678 // Set the lexical context. If the tag has a C++ scope specifier, the 5679 // lexical context will be different from the semantic context. 5680 New->setLexicalDeclContext(CurContext); 5681 5682 // Mark this as a friend decl if applicable. 5683 if (TUK == TUK_Friend) 5684 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5685 5686 // Set the access specifier. 5687 if (!Invalid && SearchDC->isRecord()) 5688 SetMemberAccessSpecifier(New, PrevDecl, AS); 5689 5690 if (TUK == TUK_Definition) 5691 New->startDefinition(); 5692 5693 // If this has an identifier, add it to the scope stack. 5694 if (TUK == TUK_Friend) { 5695 // We might be replacing an existing declaration in the lookup tables; 5696 // if so, borrow its access specifier. 5697 if (PrevDecl) 5698 New->setAccess(PrevDecl->getAccess()); 5699 5700 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5701 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5702 if (Name) // can be null along some error paths 5703 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5704 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5705 } else if (Name) { 5706 S = getNonFieldDeclScope(S); 5707 PushOnScopeChains(New, S); 5708 } else { 5709 CurContext->addDecl(New); 5710 } 5711 5712 // If this is the C FILE type, notify the AST context. 5713 if (IdentifierInfo *II = New->getIdentifier()) 5714 if (!New->isInvalidDecl() && 5715 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5716 II->isStr("FILE")) 5717 Context.setFILEDecl(New); 5718 5719 OwnedDecl = true; 5720 return DeclPtrTy::make(New); 5721} 5722 5723void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5724 AdjustDeclIfTemplate(TagD); 5725 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5726 5727 // Enter the tag context. 5728 PushDeclContext(S, Tag); 5729} 5730 5731void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5732 SourceLocation LBraceLoc) { 5733 AdjustDeclIfTemplate(TagD); 5734 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5735 5736 FieldCollector->StartClass(); 5737 5738 if (!Record->getIdentifier()) 5739 return; 5740 5741 // C++ [class]p2: 5742 // [...] The class-name is also inserted into the scope of the 5743 // class itself; this is known as the injected-class-name. For 5744 // purposes of access checking, the injected-class-name is treated 5745 // as if it were a public member name. 5746 CXXRecordDecl *InjectedClassName 5747 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5748 CurContext, Record->getLocation(), 5749 Record->getIdentifier(), 5750 Record->getTagKeywordLoc(), 5751 Record); 5752 InjectedClassName->setImplicit(); 5753 InjectedClassName->setAccess(AS_public); 5754 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5755 InjectedClassName->setDescribedClassTemplate(Template); 5756 PushOnScopeChains(InjectedClassName, S); 5757 assert(InjectedClassName->isInjectedClassName() && 5758 "Broken injected-class-name"); 5759} 5760 5761void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5762 SourceLocation RBraceLoc) { 5763 AdjustDeclIfTemplate(TagD); 5764 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5765 Tag->setRBraceLoc(RBraceLoc); 5766 5767 if (isa<CXXRecordDecl>(Tag)) 5768 FieldCollector->FinishClass(); 5769 5770 // Exit this scope of this tag's definition. 5771 PopDeclContext(); 5772 5773 // Notify the consumer that we've defined a tag. 5774 Consumer.HandleTagDeclDefinition(Tag); 5775} 5776 5777void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5778 AdjustDeclIfTemplate(TagD); 5779 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5780 Tag->setInvalidDecl(); 5781 5782 // We're undoing ActOnTagStartDefinition here, not 5783 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5784 // the FieldCollector. 5785 5786 PopDeclContext(); 5787} 5788 5789// Note that FieldName may be null for anonymous bitfields. 5790bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5791 QualType FieldTy, const Expr *BitWidth, 5792 bool *ZeroWidth) { 5793 // Default to true; that shouldn't confuse checks for emptiness 5794 if (ZeroWidth) 5795 *ZeroWidth = true; 5796 5797 // C99 6.7.2.1p4 - verify the field type. 5798 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5799 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5800 // Handle incomplete types with specific error. 5801 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5802 return true; 5803 if (FieldName) 5804 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5805 << FieldName << FieldTy << BitWidth->getSourceRange(); 5806 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5807 << FieldTy << BitWidth->getSourceRange(); 5808 } 5809 5810 // If the bit-width is type- or value-dependent, don't try to check 5811 // it now. 5812 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5813 return false; 5814 5815 llvm::APSInt Value; 5816 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5817 return true; 5818 5819 if (Value != 0 && ZeroWidth) 5820 *ZeroWidth = false; 5821 5822 // Zero-width bitfield is ok for anonymous field. 5823 if (Value == 0 && FieldName) 5824 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5825 5826 if (Value.isSigned() && Value.isNegative()) { 5827 if (FieldName) 5828 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5829 << FieldName << Value.toString(10); 5830 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5831 << Value.toString(10); 5832 } 5833 5834 if (!FieldTy->isDependentType()) { 5835 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5836 if (Value.getZExtValue() > TypeSize) { 5837 if (!getLangOptions().CPlusPlus) { 5838 if (FieldName) 5839 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5840 << FieldName << (unsigned)Value.getZExtValue() 5841 << (unsigned)TypeSize; 5842 5843 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5844 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5845 } 5846 5847 if (FieldName) 5848 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5849 << FieldName << (unsigned)Value.getZExtValue() 5850 << (unsigned)TypeSize; 5851 else 5852 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5853 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5854 } 5855 } 5856 5857 return false; 5858} 5859 5860/// ActOnField - Each field of a struct/union/class is passed into this in order 5861/// to create a FieldDecl object for it. 5862Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5863 SourceLocation DeclStart, 5864 Declarator &D, ExprTy *BitfieldWidth) { 5865 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5866 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5867 AS_public); 5868 return DeclPtrTy::make(Res); 5869} 5870 5871/// HandleField - Analyze a field of a C struct or a C++ data member. 5872/// 5873FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5874 SourceLocation DeclStart, 5875 Declarator &D, Expr *BitWidth, 5876 AccessSpecifier AS) { 5877 IdentifierInfo *II = D.getIdentifier(); 5878 SourceLocation Loc = DeclStart; 5879 if (II) Loc = D.getIdentifierLoc(); 5880 5881 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5882 QualType T = TInfo->getType(); 5883 if (getLangOptions().CPlusPlus) 5884 CheckExtraCXXDefaultArguments(D); 5885 5886 DiagnoseFunctionSpecifiers(D); 5887 5888 if (D.getDeclSpec().isThreadSpecified()) 5889 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5890 5891 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5892 ForRedeclaration); 5893 5894 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5895 // Maybe we will complain about the shadowed template parameter. 5896 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5897 // Just pretend that we didn't see the previous declaration. 5898 PrevDecl = 0; 5899 } 5900 5901 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5902 PrevDecl = 0; 5903 5904 bool Mutable 5905 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5906 SourceLocation TSSL = D.getSourceRange().getBegin(); 5907 FieldDecl *NewFD 5908 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5909 AS, PrevDecl, &D); 5910 5911 if (NewFD->isInvalidDecl()) 5912 Record->setInvalidDecl(); 5913 5914 if (NewFD->isInvalidDecl() && PrevDecl) { 5915 // Don't introduce NewFD into scope; there's already something 5916 // with the same name in the same scope. 5917 } else if (II) { 5918 PushOnScopeChains(NewFD, S); 5919 } else 5920 Record->addDecl(NewFD); 5921 5922 return NewFD; 5923} 5924 5925/// \brief Build a new FieldDecl and check its well-formedness. 5926/// 5927/// This routine builds a new FieldDecl given the fields name, type, 5928/// record, etc. \p PrevDecl should refer to any previous declaration 5929/// with the same name and in the same scope as the field to be 5930/// created. 5931/// 5932/// \returns a new FieldDecl. 5933/// 5934/// \todo The Declarator argument is a hack. It will be removed once 5935FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5936 TypeSourceInfo *TInfo, 5937 RecordDecl *Record, SourceLocation Loc, 5938 bool Mutable, Expr *BitWidth, 5939 SourceLocation TSSL, 5940 AccessSpecifier AS, NamedDecl *PrevDecl, 5941 Declarator *D) { 5942 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5943 bool InvalidDecl = false; 5944 if (D) InvalidDecl = D->isInvalidType(); 5945 5946 // If we receive a broken type, recover by assuming 'int' and 5947 // marking this declaration as invalid. 5948 if (T.isNull()) { 5949 InvalidDecl = true; 5950 T = Context.IntTy; 5951 } 5952 5953 QualType EltTy = Context.getBaseElementType(T); 5954 if (!EltTy->isDependentType() && 5955 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5956 InvalidDecl = true; 5957 5958 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5959 // than a variably modified type. 5960 if (!InvalidDecl && T->isVariablyModifiedType()) { 5961 bool SizeIsNegative; 5962 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5963 SizeIsNegative); 5964 if (!FixedTy.isNull()) { 5965 Diag(Loc, diag::warn_illegal_constant_array_size); 5966 T = FixedTy; 5967 } else { 5968 if (SizeIsNegative) 5969 Diag(Loc, diag::err_typecheck_negative_array_size); 5970 else 5971 Diag(Loc, diag::err_typecheck_field_variable_size); 5972 InvalidDecl = true; 5973 } 5974 } 5975 5976 // Fields can not have abstract class types 5977 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5978 diag::err_abstract_type_in_decl, 5979 AbstractFieldType)) 5980 InvalidDecl = true; 5981 5982 bool ZeroWidth = false; 5983 // If this is declared as a bit-field, check the bit-field. 5984 if (!InvalidDecl && BitWidth && 5985 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5986 InvalidDecl = true; 5987 DeleteExpr(BitWidth); 5988 BitWidth = 0; 5989 ZeroWidth = false; 5990 } 5991 5992 // Check that 'mutable' is consistent with the type of the declaration. 5993 if (!InvalidDecl && Mutable) { 5994 unsigned DiagID = 0; 5995 if (T->isReferenceType()) 5996 DiagID = diag::err_mutable_reference; 5997 else if (T.isConstQualified()) 5998 DiagID = diag::err_mutable_const; 5999 6000 if (DiagID) { 6001 SourceLocation ErrLoc = Loc; 6002 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6003 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6004 Diag(ErrLoc, DiagID); 6005 Mutable = false; 6006 InvalidDecl = true; 6007 } 6008 } 6009 6010 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6011 BitWidth, Mutable); 6012 if (InvalidDecl) 6013 NewFD->setInvalidDecl(); 6014 6015 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6016 Diag(Loc, diag::err_duplicate_member) << II; 6017 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6018 NewFD->setInvalidDecl(); 6019 } 6020 6021 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6022 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 6023 6024 if (!T->isPODType()) 6025 CXXRecord->setPOD(false); 6026 if (!ZeroWidth) 6027 CXXRecord->setEmpty(false); 6028 6029 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6030 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6031 if (RDecl->getDefinition()) { 6032 if (!RDecl->hasTrivialConstructor()) 6033 CXXRecord->setHasTrivialConstructor(false); 6034 if (!RDecl->hasTrivialCopyConstructor()) 6035 CXXRecord->setHasTrivialCopyConstructor(false); 6036 if (!RDecl->hasTrivialCopyAssignment()) 6037 CXXRecord->setHasTrivialCopyAssignment(false); 6038 if (!RDecl->hasTrivialDestructor()) 6039 CXXRecord->setHasTrivialDestructor(false); 6040 6041 // C++ 9.5p1: An object of a class with a non-trivial 6042 // constructor, a non-trivial copy constructor, a non-trivial 6043 // destructor, or a non-trivial copy assignment operator 6044 // cannot be a member of a union, nor can an array of such 6045 // objects. 6046 // TODO: C++0x alters this restriction significantly. 6047 if (Record->isUnion()) { 6048 // We check for copy constructors before constructors 6049 // because otherwise we'll never get complaints about 6050 // copy constructors. 6051 6052 CXXSpecialMember member = CXXInvalid; 6053 if (!RDecl->hasTrivialCopyConstructor()) 6054 member = CXXCopyConstructor; 6055 else if (!RDecl->hasTrivialConstructor()) 6056 member = CXXConstructor; 6057 else if (!RDecl->hasTrivialCopyAssignment()) 6058 member = CXXCopyAssignment; 6059 else if (!RDecl->hasTrivialDestructor()) 6060 member = CXXDestructor; 6061 6062 if (member != CXXInvalid) { 6063 Diag(Loc, diag::err_illegal_union_member) << Name << member; 6064 DiagnoseNontrivial(RT, member); 6065 NewFD->setInvalidDecl(); 6066 } 6067 } 6068 } 6069 } 6070 } 6071 6072 // FIXME: We need to pass in the attributes given an AST 6073 // representation, not a parser representation. 6074 if (D) 6075 // FIXME: What to pass instead of TUScope? 6076 ProcessDeclAttributes(TUScope, NewFD, *D); 6077 6078 if (T.isObjCGCWeak()) 6079 Diag(Loc, diag::warn_attribute_weak_on_field); 6080 6081 NewFD->setAccess(AS); 6082 6083 // C++ [dcl.init.aggr]p1: 6084 // An aggregate is an array or a class (clause 9) with [...] no 6085 // private or protected non-static data members (clause 11). 6086 // A POD must be an aggregate. 6087 if (getLangOptions().CPlusPlus && 6088 (AS == AS_private || AS == AS_protected)) { 6089 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 6090 CXXRecord->setAggregate(false); 6091 CXXRecord->setPOD(false); 6092 } 6093 6094 return NewFD; 6095} 6096 6097/// DiagnoseNontrivial - Given that a class has a non-trivial 6098/// special member, figure out why. 6099void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6100 QualType QT(T, 0U); 6101 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6102 6103 // Check whether the member was user-declared. 6104 switch (member) { 6105 case CXXInvalid: 6106 break; 6107 6108 case CXXConstructor: 6109 if (RD->hasUserDeclaredConstructor()) { 6110 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6111 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6112 const FunctionDecl *body = 0; 6113 ci->hasBody(body); 6114 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6115 SourceLocation CtorLoc = ci->getLocation(); 6116 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6117 return; 6118 } 6119 } 6120 6121 assert(0 && "found no user-declared constructors"); 6122 return; 6123 } 6124 break; 6125 6126 case CXXCopyConstructor: 6127 if (RD->hasUserDeclaredCopyConstructor()) { 6128 SourceLocation CtorLoc = 6129 RD->getCopyConstructor(Context, 0)->getLocation(); 6130 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6131 return; 6132 } 6133 break; 6134 6135 case CXXCopyAssignment: 6136 if (RD->hasUserDeclaredCopyAssignment()) { 6137 // FIXME: this should use the location of the copy 6138 // assignment, not the type. 6139 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6140 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6141 return; 6142 } 6143 break; 6144 6145 case CXXDestructor: 6146 if (RD->hasUserDeclaredDestructor()) { 6147 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6148 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6149 return; 6150 } 6151 break; 6152 } 6153 6154 typedef CXXRecordDecl::base_class_iterator base_iter; 6155 6156 // Virtual bases and members inhibit trivial copying/construction, 6157 // but not trivial destruction. 6158 if (member != CXXDestructor) { 6159 // Check for virtual bases. vbases includes indirect virtual bases, 6160 // so we just iterate through the direct bases. 6161 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6162 if (bi->isVirtual()) { 6163 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6164 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6165 return; 6166 } 6167 6168 // Check for virtual methods. 6169 typedef CXXRecordDecl::method_iterator meth_iter; 6170 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6171 ++mi) { 6172 if (mi->isVirtual()) { 6173 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6174 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6175 return; 6176 } 6177 } 6178 } 6179 6180 bool (CXXRecordDecl::*hasTrivial)() const; 6181 switch (member) { 6182 case CXXConstructor: 6183 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6184 case CXXCopyConstructor: 6185 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6186 case CXXCopyAssignment: 6187 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6188 case CXXDestructor: 6189 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6190 default: 6191 assert(0 && "unexpected special member"); return; 6192 } 6193 6194 // Check for nontrivial bases (and recurse). 6195 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6196 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6197 assert(BaseRT && "Don't know how to handle dependent bases"); 6198 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6199 if (!(BaseRecTy->*hasTrivial)()) { 6200 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6201 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6202 DiagnoseNontrivial(BaseRT, member); 6203 return; 6204 } 6205 } 6206 6207 // Check for nontrivial members (and recurse). 6208 typedef RecordDecl::field_iterator field_iter; 6209 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6210 ++fi) { 6211 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6212 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6213 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6214 6215 if (!(EltRD->*hasTrivial)()) { 6216 SourceLocation FLoc = (*fi)->getLocation(); 6217 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6218 DiagnoseNontrivial(EltRT, member); 6219 return; 6220 } 6221 } 6222 } 6223 6224 assert(0 && "found no explanation for non-trivial member"); 6225} 6226 6227/// TranslateIvarVisibility - Translate visibility from a token ID to an 6228/// AST enum value. 6229static ObjCIvarDecl::AccessControl 6230TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6231 switch (ivarVisibility) { 6232 default: assert(0 && "Unknown visitibility kind"); 6233 case tok::objc_private: return ObjCIvarDecl::Private; 6234 case tok::objc_public: return ObjCIvarDecl::Public; 6235 case tok::objc_protected: return ObjCIvarDecl::Protected; 6236 case tok::objc_package: return ObjCIvarDecl::Package; 6237 } 6238} 6239 6240/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6241/// in order to create an IvarDecl object for it. 6242Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6243 SourceLocation DeclStart, 6244 DeclPtrTy IntfDecl, 6245 Declarator &D, ExprTy *BitfieldWidth, 6246 tok::ObjCKeywordKind Visibility) { 6247 6248 IdentifierInfo *II = D.getIdentifier(); 6249 Expr *BitWidth = (Expr*)BitfieldWidth; 6250 SourceLocation Loc = DeclStart; 6251 if (II) Loc = D.getIdentifierLoc(); 6252 6253 // FIXME: Unnamed fields can be handled in various different ways, for 6254 // example, unnamed unions inject all members into the struct namespace! 6255 6256 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6257 QualType T = TInfo->getType(); 6258 6259 if (BitWidth) { 6260 // 6.7.2.1p3, 6.7.2.1p4 6261 if (VerifyBitField(Loc, II, T, BitWidth)) { 6262 D.setInvalidType(); 6263 DeleteExpr(BitWidth); 6264 BitWidth = 0; 6265 } 6266 } else { 6267 // Not a bitfield. 6268 6269 // validate II. 6270 6271 } 6272 if (T->isReferenceType()) { 6273 Diag(Loc, diag::err_ivar_reference_type); 6274 D.setInvalidType(); 6275 } 6276 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6277 // than a variably modified type. 6278 else if (T->isVariablyModifiedType()) { 6279 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6280 D.setInvalidType(); 6281 } 6282 6283 // Get the visibility (access control) for this ivar. 6284 ObjCIvarDecl::AccessControl ac = 6285 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6286 : ObjCIvarDecl::None; 6287 // Must set ivar's DeclContext to its enclosing interface. 6288 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6289 ObjCContainerDecl *EnclosingContext; 6290 if (ObjCImplementationDecl *IMPDecl = 6291 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6292 // Case of ivar declared in an implementation. Context is that of its class. 6293 EnclosingContext = IMPDecl->getClassInterface(); 6294 assert(EnclosingContext && "Implementation has no class interface!"); 6295 } else { 6296 if (ObjCCategoryDecl *CDecl = 6297 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6298 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6299 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6300 return DeclPtrTy(); 6301 } 6302 } 6303 EnclosingContext = EnclosingDecl; 6304 } 6305 6306 // Construct the decl. 6307 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6308 EnclosingContext, Loc, II, T, 6309 TInfo, ac, (Expr *)BitfieldWidth); 6310 6311 if (II) { 6312 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6313 ForRedeclaration); 6314 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6315 && !isa<TagDecl>(PrevDecl)) { 6316 Diag(Loc, diag::err_duplicate_member) << II; 6317 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6318 NewID->setInvalidDecl(); 6319 } 6320 } 6321 6322 // Process attributes attached to the ivar. 6323 ProcessDeclAttributes(S, NewID, D); 6324 6325 if (D.isInvalidType()) 6326 NewID->setInvalidDecl(); 6327 6328 if (II) { 6329 // FIXME: When interfaces are DeclContexts, we'll need to add 6330 // these to the interface. 6331 S->AddDecl(DeclPtrTy::make(NewID)); 6332 IdResolver.AddDecl(NewID); 6333 } 6334 6335 return DeclPtrTy::make(NewID); 6336} 6337 6338void Sema::ActOnFields(Scope* S, 6339 SourceLocation RecLoc, DeclPtrTy RecDecl, 6340 DeclPtrTy *Fields, unsigned NumFields, 6341 SourceLocation LBrac, SourceLocation RBrac, 6342 AttributeList *Attr) { 6343 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6344 assert(EnclosingDecl && "missing record or interface decl"); 6345 6346 // If the decl this is being inserted into is invalid, then it may be a 6347 // redeclaration or some other bogus case. Don't try to add fields to it. 6348 if (EnclosingDecl->isInvalidDecl()) { 6349 // FIXME: Deallocate fields? 6350 return; 6351 } 6352 6353 6354 // Verify that all the fields are okay. 6355 unsigned NumNamedMembers = 0; 6356 llvm::SmallVector<FieldDecl*, 32> RecFields; 6357 6358 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6359 for (unsigned i = 0; i != NumFields; ++i) { 6360 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6361 6362 // Get the type for the field. 6363 Type *FDTy = FD->getType().getTypePtr(); 6364 6365 if (!FD->isAnonymousStructOrUnion()) { 6366 // Remember all fields written by the user. 6367 RecFields.push_back(FD); 6368 } 6369 6370 // If the field is already invalid for some reason, don't emit more 6371 // diagnostics about it. 6372 if (FD->isInvalidDecl()) { 6373 EnclosingDecl->setInvalidDecl(); 6374 continue; 6375 } 6376 6377 // C99 6.7.2.1p2: 6378 // A structure or union shall not contain a member with 6379 // incomplete or function type (hence, a structure shall not 6380 // contain an instance of itself, but may contain a pointer to 6381 // an instance of itself), except that the last member of a 6382 // structure with more than one named member may have incomplete 6383 // array type; such a structure (and any union containing, 6384 // possibly recursively, a member that is such a structure) 6385 // shall not be a member of a structure or an element of an 6386 // array. 6387 if (FDTy->isFunctionType()) { 6388 // Field declared as a function. 6389 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6390 << FD->getDeclName(); 6391 FD->setInvalidDecl(); 6392 EnclosingDecl->setInvalidDecl(); 6393 continue; 6394 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6395 Record && Record->isStruct()) { 6396 // Flexible array member. 6397 if (NumNamedMembers < 1) { 6398 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6399 << FD->getDeclName(); 6400 FD->setInvalidDecl(); 6401 EnclosingDecl->setInvalidDecl(); 6402 continue; 6403 } 6404 if (!FD->getType()->isDependentType() && 6405 !Context.getBaseElementType(FD->getType())->isPODType()) { 6406 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6407 << FD->getDeclName() << FD->getType(); 6408 FD->setInvalidDecl(); 6409 EnclosingDecl->setInvalidDecl(); 6410 continue; 6411 } 6412 6413 // Okay, we have a legal flexible array member at the end of the struct. 6414 if (Record) 6415 Record->setHasFlexibleArrayMember(true); 6416 } else if (!FDTy->isDependentType() && 6417 RequireCompleteType(FD->getLocation(), FD->getType(), 6418 diag::err_field_incomplete)) { 6419 // Incomplete type 6420 FD->setInvalidDecl(); 6421 EnclosingDecl->setInvalidDecl(); 6422 continue; 6423 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6424 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6425 // If this is a member of a union, then entire union becomes "flexible". 6426 if (Record && Record->isUnion()) { 6427 Record->setHasFlexibleArrayMember(true); 6428 } else { 6429 // If this is a struct/class and this is not the last element, reject 6430 // it. Note that GCC supports variable sized arrays in the middle of 6431 // structures. 6432 if (i != NumFields-1) 6433 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6434 << FD->getDeclName() << FD->getType(); 6435 else { 6436 // We support flexible arrays at the end of structs in 6437 // other structs as an extension. 6438 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6439 << FD->getDeclName(); 6440 if (Record) 6441 Record->setHasFlexibleArrayMember(true); 6442 } 6443 } 6444 } 6445 if (Record && FDTTy->getDecl()->hasObjectMember()) 6446 Record->setHasObjectMember(true); 6447 } else if (FDTy->isObjCObjectType()) { 6448 /// A field cannot be an Objective-c object 6449 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6450 FD->setInvalidDecl(); 6451 EnclosingDecl->setInvalidDecl(); 6452 continue; 6453 } else if (getLangOptions().ObjC1 && 6454 getLangOptions().getGCMode() != LangOptions::NonGC && 6455 Record && 6456 (FD->getType()->isObjCObjectPointerType() || 6457 FD->getType().isObjCGCStrong())) 6458 Record->setHasObjectMember(true); 6459 else if (Context.getAsArrayType(FD->getType())) { 6460 QualType BaseType = Context.getBaseElementType(FD->getType()); 6461 if (Record && BaseType->isRecordType() && 6462 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6463 Record->setHasObjectMember(true); 6464 } 6465 // Keep track of the number of named members. 6466 if (FD->getIdentifier()) 6467 ++NumNamedMembers; 6468 } 6469 6470 // Okay, we successfully defined 'Record'. 6471 if (Record) { 6472 Record->completeDefinition(); 6473 } else { 6474 ObjCIvarDecl **ClsFields = 6475 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6476 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6477 ID->setLocEnd(RBrac); 6478 // Add ivar's to class's DeclContext. 6479 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6480 ClsFields[i]->setLexicalDeclContext(ID); 6481 ID->addDecl(ClsFields[i]); 6482 } 6483 // Must enforce the rule that ivars in the base classes may not be 6484 // duplicates. 6485 if (ID->getSuperClass()) 6486 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6487 } else if (ObjCImplementationDecl *IMPDecl = 6488 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6489 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6490 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6491 // Ivar declared in @implementation never belongs to the implementation. 6492 // Only it is in implementation's lexical context. 6493 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6494 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6495 } else if (ObjCCategoryDecl *CDecl = 6496 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6497 // case of ivars in class extension; all other cases have been 6498 // reported as errors elsewhere. 6499 // FIXME. Class extension does not have a LocEnd field. 6500 // CDecl->setLocEnd(RBrac); 6501 // Add ivar's to class extension's DeclContext. 6502 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6503 ClsFields[i]->setLexicalDeclContext(CDecl); 6504 CDecl->addDecl(ClsFields[i]); 6505 } 6506 } 6507 } 6508 6509 if (Attr) 6510 ProcessDeclAttributeList(S, Record, Attr); 6511 6512 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6513 // set the visibility of this record. 6514 if (Record && !Record->getDeclContext()->isRecord()) 6515 AddPushedVisibilityAttribute(Record); 6516} 6517 6518/// \brief Determine whether the given integral value is representable within 6519/// the given type T. 6520static bool isRepresentableIntegerValue(ASTContext &Context, 6521 llvm::APSInt &Value, 6522 QualType T) { 6523 assert(T->isIntegralType(Context) && "Integral type required!"); 6524 unsigned BitWidth = Context.getIntWidth(T); 6525 6526 if (Value.isUnsigned() || Value.isNonNegative()) 6527 return Value.getActiveBits() < BitWidth; 6528 6529 return Value.getMinSignedBits() <= BitWidth; 6530} 6531 6532// \brief Given an integral type, return the next larger integral type 6533// (or a NULL type of no such type exists). 6534static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6535 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6536 // enum checking below. 6537 assert(T->isIntegralType(Context) && "Integral type required!"); 6538 const unsigned NumTypes = 4; 6539 QualType SignedIntegralTypes[NumTypes] = { 6540 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6541 }; 6542 QualType UnsignedIntegralTypes[NumTypes] = { 6543 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6544 Context.UnsignedLongLongTy 6545 }; 6546 6547 unsigned BitWidth = Context.getTypeSize(T); 6548 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6549 : UnsignedIntegralTypes; 6550 for (unsigned I = 0; I != NumTypes; ++I) 6551 if (Context.getTypeSize(Types[I]) > BitWidth) 6552 return Types[I]; 6553 6554 return QualType(); 6555} 6556 6557EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6558 EnumConstantDecl *LastEnumConst, 6559 SourceLocation IdLoc, 6560 IdentifierInfo *Id, 6561 ExprArg val) { 6562 Expr *Val = (Expr *)val.get(); 6563 6564 unsigned IntWidth = Context.Target.getIntWidth(); 6565 llvm::APSInt EnumVal(IntWidth); 6566 QualType EltTy; 6567 if (Val) { 6568 if (Enum->isDependentType() || Val->isTypeDependent()) 6569 EltTy = Context.DependentTy; 6570 else { 6571 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6572 SourceLocation ExpLoc; 6573 if (!Val->isValueDependent() && 6574 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6575 Val = 0; 6576 } else { 6577 if (!getLangOptions().CPlusPlus) { 6578 // C99 6.7.2.2p2: 6579 // The expression that defines the value of an enumeration constant 6580 // shall be an integer constant expression that has a value 6581 // representable as an int. 6582 6583 // Complain if the value is not representable in an int. 6584 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6585 Diag(IdLoc, diag::ext_enum_value_not_int) 6586 << EnumVal.toString(10) << Val->getSourceRange() 6587 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6588 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6589 // Force the type of the expression to 'int'. 6590 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6591 6592 if (Val != val.get()) { 6593 val.release(); 6594 val = Val; 6595 } 6596 } 6597 } 6598 6599 // C++0x [dcl.enum]p5: 6600 // If the underlying type is not fixed, the type of each enumerator 6601 // is the type of its initializing value: 6602 // - If an initializer is specified for an enumerator, the 6603 // initializing value has the same type as the expression. 6604 EltTy = Val->getType(); 6605 } 6606 } 6607 } 6608 6609 if (!Val) { 6610 if (Enum->isDependentType()) 6611 EltTy = Context.DependentTy; 6612 else if (!LastEnumConst) { 6613 // C++0x [dcl.enum]p5: 6614 // If the underlying type is not fixed, the type of each enumerator 6615 // is the type of its initializing value: 6616 // - If no initializer is specified for the first enumerator, the 6617 // initializing value has an unspecified integral type. 6618 // 6619 // GCC uses 'int' for its unspecified integral type, as does 6620 // C99 6.7.2.2p3. 6621 EltTy = Context.IntTy; 6622 } else { 6623 // Assign the last value + 1. 6624 EnumVal = LastEnumConst->getInitVal(); 6625 ++EnumVal; 6626 EltTy = LastEnumConst->getType(); 6627 6628 // Check for overflow on increment. 6629 if (EnumVal < LastEnumConst->getInitVal()) { 6630 // C++0x [dcl.enum]p5: 6631 // If the underlying type is not fixed, the type of each enumerator 6632 // is the type of its initializing value: 6633 // 6634 // - Otherwise the type of the initializing value is the same as 6635 // the type of the initializing value of the preceding enumerator 6636 // unless the incremented value is not representable in that type, 6637 // in which case the type is an unspecified integral type 6638 // sufficient to contain the incremented value. If no such type 6639 // exists, the program is ill-formed. 6640 QualType T = getNextLargerIntegralType(Context, EltTy); 6641 if (T.isNull()) { 6642 // There is no integral type larger enough to represent this 6643 // value. Complain, then allow the value to wrap around. 6644 EnumVal = LastEnumConst->getInitVal(); 6645 EnumVal.zext(EnumVal.getBitWidth() * 2); 6646 Diag(IdLoc, diag::warn_enumerator_too_large) 6647 << EnumVal.toString(10); 6648 } else { 6649 EltTy = T; 6650 } 6651 6652 // Retrieve the last enumerator's value, extent that type to the 6653 // type that is supposed to be large enough to represent the incremented 6654 // value, then increment. 6655 EnumVal = LastEnumConst->getInitVal(); 6656 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6657 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6658 ++EnumVal; 6659 6660 // If we're not in C++, diagnose the overflow of enumerator values, 6661 // which in C99 means that the enumerator value is not representable in 6662 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6663 // permits enumerator values that are representable in some larger 6664 // integral type. 6665 if (!getLangOptions().CPlusPlus && !T.isNull()) 6666 Diag(IdLoc, diag::warn_enum_value_overflow); 6667 } else if (!getLangOptions().CPlusPlus && 6668 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6669 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6670 Diag(IdLoc, diag::ext_enum_value_not_int) 6671 << EnumVal.toString(10) << 1; 6672 } 6673 } 6674 } 6675 6676 if (!EltTy->isDependentType()) { 6677 // Make the enumerator value match the signedness and size of the 6678 // enumerator's type. 6679 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6680 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6681 } 6682 6683 val.release(); 6684 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6685 Val, EnumVal); 6686} 6687 6688 6689Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6690 DeclPtrTy lastEnumConst, 6691 SourceLocation IdLoc, 6692 IdentifierInfo *Id, 6693 SourceLocation EqualLoc, ExprTy *val) { 6694 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6695 EnumConstantDecl *LastEnumConst = 6696 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6697 Expr *Val = static_cast<Expr*>(val); 6698 6699 // The scope passed in may not be a decl scope. Zip up the scope tree until 6700 // we find one that is. 6701 S = getNonFieldDeclScope(S); 6702 6703 // Verify that there isn't already something declared with this name in this 6704 // scope. 6705 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6706 ForRedeclaration); 6707 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6708 // Maybe we will complain about the shadowed template parameter. 6709 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6710 // Just pretend that we didn't see the previous declaration. 6711 PrevDecl = 0; 6712 } 6713 6714 if (PrevDecl) { 6715 // When in C++, we may get a TagDecl with the same name; in this case the 6716 // enum constant will 'hide' the tag. 6717 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6718 "Received TagDecl when not in C++!"); 6719 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6720 if (isa<EnumConstantDecl>(PrevDecl)) 6721 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6722 else 6723 Diag(IdLoc, diag::err_redefinition) << Id; 6724 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6725 return DeclPtrTy(); 6726 } 6727 } 6728 6729 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6730 IdLoc, Id, Owned(Val)); 6731 6732 // Register this decl in the current scope stack. 6733 if (New) { 6734 New->setAccess(TheEnumDecl->getAccess()); 6735 PushOnScopeChains(New, S); 6736 } 6737 6738 return DeclPtrTy::make(New); 6739} 6740 6741void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6742 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6743 DeclPtrTy *Elements, unsigned NumElements, 6744 Scope *S, AttributeList *Attr) { 6745 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6746 QualType EnumType = Context.getTypeDeclType(Enum); 6747 6748 if (Attr) 6749 ProcessDeclAttributeList(S, Enum, Attr); 6750 6751 if (Enum->isDependentType()) { 6752 for (unsigned i = 0; i != NumElements; ++i) { 6753 EnumConstantDecl *ECD = 6754 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6755 if (!ECD) continue; 6756 6757 ECD->setType(EnumType); 6758 } 6759 6760 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6761 return; 6762 } 6763 6764 // TODO: If the result value doesn't fit in an int, it must be a long or long 6765 // long value. ISO C does not support this, but GCC does as an extension, 6766 // emit a warning. 6767 unsigned IntWidth = Context.Target.getIntWidth(); 6768 unsigned CharWidth = Context.Target.getCharWidth(); 6769 unsigned ShortWidth = Context.Target.getShortWidth(); 6770 6771 // Verify that all the values are okay, compute the size of the values, and 6772 // reverse the list. 6773 unsigned NumNegativeBits = 0; 6774 unsigned NumPositiveBits = 0; 6775 6776 // Keep track of whether all elements have type int. 6777 bool AllElementsInt = true; 6778 6779 for (unsigned i = 0; i != NumElements; ++i) { 6780 EnumConstantDecl *ECD = 6781 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6782 if (!ECD) continue; // Already issued a diagnostic. 6783 6784 const llvm::APSInt &InitVal = ECD->getInitVal(); 6785 6786 // Keep track of the size of positive and negative values. 6787 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6788 NumPositiveBits = std::max(NumPositiveBits, 6789 (unsigned)InitVal.getActiveBits()); 6790 else 6791 NumNegativeBits = std::max(NumNegativeBits, 6792 (unsigned)InitVal.getMinSignedBits()); 6793 6794 // Keep track of whether every enum element has type int (very commmon). 6795 if (AllElementsInt) 6796 AllElementsInt = ECD->getType() == Context.IntTy; 6797 } 6798 6799 // Figure out the type that should be used for this enum. 6800 // FIXME: Support -fshort-enums. 6801 QualType BestType; 6802 unsigned BestWidth; 6803 6804 // C++0x N3000 [conv.prom]p3: 6805 // An rvalue of an unscoped enumeration type whose underlying 6806 // type is not fixed can be converted to an rvalue of the first 6807 // of the following types that can represent all the values of 6808 // the enumeration: int, unsigned int, long int, unsigned long 6809 // int, long long int, or unsigned long long int. 6810 // C99 6.4.4.3p2: 6811 // An identifier declared as an enumeration constant has type int. 6812 // The C99 rule is modified by a gcc extension 6813 QualType BestPromotionType; 6814 6815 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6816 6817 if (NumNegativeBits) { 6818 // If there is a negative value, figure out the smallest integer type (of 6819 // int/long/longlong) that fits. 6820 // If it's packed, check also if it fits a char or a short. 6821 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6822 BestType = Context.SignedCharTy; 6823 BestWidth = CharWidth; 6824 } else if (Packed && NumNegativeBits <= ShortWidth && 6825 NumPositiveBits < ShortWidth) { 6826 BestType = Context.ShortTy; 6827 BestWidth = ShortWidth; 6828 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6829 BestType = Context.IntTy; 6830 BestWidth = IntWidth; 6831 } else { 6832 BestWidth = Context.Target.getLongWidth(); 6833 6834 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6835 BestType = Context.LongTy; 6836 } else { 6837 BestWidth = Context.Target.getLongLongWidth(); 6838 6839 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6840 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6841 BestType = Context.LongLongTy; 6842 } 6843 } 6844 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6845 } else { 6846 // If there is no negative value, figure out the smallest type that fits 6847 // all of the enumerator values. 6848 // If it's packed, check also if it fits a char or a short. 6849 if (Packed && NumPositiveBits <= CharWidth) { 6850 BestType = Context.UnsignedCharTy; 6851 BestPromotionType = Context.IntTy; 6852 BestWidth = CharWidth; 6853 } else if (Packed && NumPositiveBits <= ShortWidth) { 6854 BestType = Context.UnsignedShortTy; 6855 BestPromotionType = Context.IntTy; 6856 BestWidth = ShortWidth; 6857 } else if (NumPositiveBits <= IntWidth) { 6858 BestType = Context.UnsignedIntTy; 6859 BestWidth = IntWidth; 6860 BestPromotionType 6861 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6862 ? Context.UnsignedIntTy : Context.IntTy; 6863 } else if (NumPositiveBits <= 6864 (BestWidth = Context.Target.getLongWidth())) { 6865 BestType = Context.UnsignedLongTy; 6866 BestPromotionType 6867 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6868 ? Context.UnsignedLongTy : Context.LongTy; 6869 } else { 6870 BestWidth = Context.Target.getLongLongWidth(); 6871 assert(NumPositiveBits <= BestWidth && 6872 "How could an initializer get larger than ULL?"); 6873 BestType = Context.UnsignedLongLongTy; 6874 BestPromotionType 6875 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6876 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6877 } 6878 } 6879 6880 // Loop over all of the enumerator constants, changing their types to match 6881 // the type of the enum if needed. 6882 for (unsigned i = 0; i != NumElements; ++i) { 6883 EnumConstantDecl *ECD = 6884 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6885 if (!ECD) continue; // Already issued a diagnostic. 6886 6887 // Standard C says the enumerators have int type, but we allow, as an 6888 // extension, the enumerators to be larger than int size. If each 6889 // enumerator value fits in an int, type it as an int, otherwise type it the 6890 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6891 // that X has type 'int', not 'unsigned'. 6892 6893 // Determine whether the value fits into an int. 6894 llvm::APSInt InitVal = ECD->getInitVal(); 6895 6896 // If it fits into an integer type, force it. Otherwise force it to match 6897 // the enum decl type. 6898 QualType NewTy; 6899 unsigned NewWidth; 6900 bool NewSign; 6901 if (!getLangOptions().CPlusPlus && 6902 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6903 NewTy = Context.IntTy; 6904 NewWidth = IntWidth; 6905 NewSign = true; 6906 } else if (ECD->getType() == BestType) { 6907 // Already the right type! 6908 if (getLangOptions().CPlusPlus) 6909 // C++ [dcl.enum]p4: Following the closing brace of an 6910 // enum-specifier, each enumerator has the type of its 6911 // enumeration. 6912 ECD->setType(EnumType); 6913 continue; 6914 } else { 6915 NewTy = BestType; 6916 NewWidth = BestWidth; 6917 NewSign = BestType->isSignedIntegerType(); 6918 } 6919 6920 // Adjust the APSInt value. 6921 InitVal.extOrTrunc(NewWidth); 6922 InitVal.setIsSigned(NewSign); 6923 ECD->setInitVal(InitVal); 6924 6925 // Adjust the Expr initializer and type. 6926 if (ECD->getInitExpr()) 6927 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 6928 CastExpr::CK_IntegralCast, 6929 ECD->getInitExpr(), 6930 /*base paths*/ 0, 6931 ImplicitCastExpr::RValue)); 6932 if (getLangOptions().CPlusPlus) 6933 // C++ [dcl.enum]p4: Following the closing brace of an 6934 // enum-specifier, each enumerator has the type of its 6935 // enumeration. 6936 ECD->setType(EnumType); 6937 else 6938 ECD->setType(NewTy); 6939 } 6940 6941 Enum->completeDefinition(BestType, BestPromotionType, 6942 NumPositiveBits, NumNegativeBits); 6943} 6944 6945Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6946 ExprArg expr) { 6947 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6948 6949 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6950 Loc, AsmString); 6951 CurContext->addDecl(New); 6952 return DeclPtrTy::make(New); 6953} 6954 6955void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6956 SourceLocation PragmaLoc, 6957 SourceLocation NameLoc) { 6958 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6959 6960 if (PrevDecl) { 6961 PrevDecl->addAttr(::new (Context) WeakAttr()); 6962 } else { 6963 (void)WeakUndeclaredIdentifiers.insert( 6964 std::pair<IdentifierInfo*,WeakInfo> 6965 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6966 } 6967} 6968 6969void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6970 IdentifierInfo* AliasName, 6971 SourceLocation PragmaLoc, 6972 SourceLocation NameLoc, 6973 SourceLocation AliasNameLoc) { 6974 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6975 LookupOrdinaryName); 6976 WeakInfo W = WeakInfo(Name, NameLoc); 6977 6978 if (PrevDecl) { 6979 if (!PrevDecl->hasAttr<AliasAttr>()) 6980 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6981 DeclApplyPragmaWeak(TUScope, ND, W); 6982 } else { 6983 (void)WeakUndeclaredIdentifiers.insert( 6984 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6985 } 6986} 6987