SemaDecl.cpp revision cb710a4df50b79659399f0722ea29e90251ea834
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "TypeLocBuilder.h" 21#include "clang/AST/APValue.h" 22#include "clang/AST/ASTConsumer.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclCXX.h" 26#include "clang/AST/DeclObjC.h" 27#include "clang/AST/DeclTemplate.h" 28#include "clang/AST/ExprCXX.h" 29#include "clang/AST/StmtCXX.h" 30#include "clang/AST/CharUnits.h" 31#include "clang/Sema/DeclSpec.h" 32#include "clang/Sema/ParsedTemplate.h" 33#include "clang/Parse/ParseDiagnostic.h" 34#include "clang/Basic/PartialDiagnostic.h" 35#include "clang/Basic/SourceManager.h" 36#include "clang/Basic/TargetInfo.h" 37// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 38#include "clang/Lex/Preprocessor.h" 39#include "clang/Lex/HeaderSearch.h" 40#include "llvm/ADT/Triple.h" 41#include <algorithm> 42#include <cstring> 43#include <functional> 44using namespace clang; 45using namespace sema; 46 47Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 48 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 49} 50 51/// \brief If the identifier refers to a type name within this scope, 52/// return the declaration of that type. 53/// 54/// This routine performs ordinary name lookup of the identifier II 55/// within the given scope, with optional C++ scope specifier SS, to 56/// determine whether the name refers to a type. If so, returns an 57/// opaque pointer (actually a QualType) corresponding to that 58/// type. Otherwise, returns NULL. 59/// 60/// If name lookup results in an ambiguity, this routine will complain 61/// and then return NULL. 62ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, CXXScopeSpec *SS, 64 bool isClassName, bool HasTrailingDot, 65 ParsedType ObjectTypePtr, 66 bool WantNontrivialTypeSourceInfo) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = ObjectTypePtr.get(); 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 ParsedType(); 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 if (WantNontrivialTypeSourceInfo) 93 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 94 95 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 96 QualType T = 97 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 98 II, NameLoc); 99 100 return ParsedType::make(T); 101 } 102 103 return ParsedType(); 104 } 105 106 if (!LookupCtx->isDependentContext() && 107 RequireCompleteDeclContext(*SS, LookupCtx)) 108 return ParsedType(); 109 } 110 111 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 112 // lookup for class-names. 113 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 114 LookupOrdinaryName; 115 LookupResult Result(*this, &II, NameLoc, Kind); 116 if (LookupCtx) { 117 // Perform "qualified" name lookup into the declaration context we 118 // computed, which is either the type of the base of a member access 119 // expression or the declaration context associated with a prior 120 // nested-name-specifier. 121 LookupQualifiedName(Result, LookupCtx); 122 123 if (ObjectTypePtr && Result.empty()) { 124 // C++ [basic.lookup.classref]p3: 125 // If the unqualified-id is ~type-name, the type-name is looked up 126 // in the context of the entire postfix-expression. If the type T of 127 // the object expression is of a class type C, the type-name is also 128 // looked up in the scope of class C. At least one of the lookups shall 129 // find a name that refers to (possibly cv-qualified) T. 130 LookupName(Result, S); 131 } 132 } else { 133 // Perform unqualified name lookup. 134 LookupName(Result, S); 135 } 136 137 NamedDecl *IIDecl = 0; 138 switch (Result.getResultKind()) { 139 case LookupResult::NotFound: 140 case LookupResult::NotFoundInCurrentInstantiation: 141 case LookupResult::FoundOverloaded: 142 case LookupResult::FoundUnresolvedValue: 143 Result.suppressDiagnostics(); 144 return ParsedType(); 145 146 case LookupResult::Ambiguous: 147 // Recover from type-hiding ambiguities by hiding the type. We'll 148 // do the lookup again when looking for an object, and we can 149 // diagnose the error then. If we don't do this, then the error 150 // about hiding the type will be immediately followed by an error 151 // that only makes sense if the identifier was treated like a type. 152 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 153 Result.suppressDiagnostics(); 154 return ParsedType(); 155 } 156 157 // Look to see if we have a type anywhere in the list of results. 158 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 159 Res != ResEnd; ++Res) { 160 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 161 if (!IIDecl || 162 (*Res)->getLocation().getRawEncoding() < 163 IIDecl->getLocation().getRawEncoding()) 164 IIDecl = *Res; 165 } 166 } 167 168 if (!IIDecl) { 169 // None of the entities we found is a type, so there is no way 170 // to even assume that the result is a type. In this case, don't 171 // complain about the ambiguity. The parser will either try to 172 // perform this lookup again (e.g., as an object name), which 173 // will produce the ambiguity, or will complain that it expected 174 // a type name. 175 Result.suppressDiagnostics(); 176 return ParsedType(); 177 } 178 179 // We found a type within the ambiguous lookup; diagnose the 180 // ambiguity and then return that type. This might be the right 181 // answer, or it might not be, but it suppresses any attempt to 182 // perform the name lookup again. 183 break; 184 185 case LookupResult::Found: 186 IIDecl = Result.getFoundDecl(); 187 break; 188 } 189 190 assert(IIDecl && "Didn't find decl"); 191 192 QualType T; 193 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 194 DiagnoseUseOfDecl(IIDecl, NameLoc); 195 196 if (T.isNull()) 197 T = Context.getTypeDeclType(TD); 198 199 if (SS && SS->isNotEmpty()) { 200 if (WantNontrivialTypeSourceInfo) { 201 // Construct a type with type-source information. 202 TypeLocBuilder Builder; 203 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 204 205 T = getElaboratedType(ETK_None, *SS, T); 206 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 207 ElabTL.setKeywordLoc(SourceLocation()); 208 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 209 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 210 } else { 211 T = getElaboratedType(ETK_None, *SS, T); 212 } 213 } 214 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 215 if (!HasTrailingDot) 216 T = Context.getObjCInterfaceType(IDecl); 217 } 218 219 if (T.isNull()) { 220 // If it's not plausibly a type, suppress diagnostics. 221 Result.suppressDiagnostics(); 222 return ParsedType(); 223 } 224 return ParsedType::make(T); 225} 226 227/// isTagName() - This method is called *for error recovery purposes only* 228/// to determine if the specified name is a valid tag name ("struct foo"). If 229/// so, this returns the TST for the tag corresponding to it (TST_enum, 230/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 231/// where the user forgot to specify the tag. 232DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 233 // Do a tag name lookup in this scope. 234 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 235 LookupName(R, S, false); 236 R.suppressDiagnostics(); 237 if (R.getResultKind() == LookupResult::Found) 238 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 239 switch (TD->getTagKind()) { 240 default: return DeclSpec::TST_unspecified; 241 case TTK_Struct: return DeclSpec::TST_struct; 242 case TTK_Union: return DeclSpec::TST_union; 243 case TTK_Class: return DeclSpec::TST_class; 244 case TTK_Enum: return DeclSpec::TST_enum; 245 } 246 } 247 248 return DeclSpec::TST_unspecified; 249} 250 251bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 252 SourceLocation IILoc, 253 Scope *S, 254 CXXScopeSpec *SS, 255 ParsedType &SuggestedType) { 256 // We don't have anything to suggest (yet). 257 SuggestedType = ParsedType(); 258 259 // There may have been a typo in the name of the type. Look up typo 260 // results, in case we have something that we can suggest. 261 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 262 NotForRedeclaration); 263 264 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 265 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 266 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 267 !Result->isInvalidDecl()) { 268 // We found a similarly-named type or interface; suggest that. 269 if (!SS || !SS->isSet()) 270 Diag(IILoc, diag::err_unknown_typename_suggest) 271 << &II << Lookup.getLookupName() 272 << FixItHint::CreateReplacement(SourceRange(IILoc), 273 Result->getNameAsString()); 274 else if (DeclContext *DC = computeDeclContext(*SS, false)) 275 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 276 << &II << DC << Lookup.getLookupName() << SS->getRange() 277 << FixItHint::CreateReplacement(SourceRange(IILoc), 278 Result->getNameAsString()); 279 else 280 llvm_unreachable("could not have corrected a typo here"); 281 282 Diag(Result->getLocation(), diag::note_previous_decl) 283 << Result->getDeclName(); 284 285 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 286 false, false, ParsedType(), 287 /*NonTrivialTypeSourceInfo=*/true); 288 return true; 289 } 290 } else if (Lookup.empty()) { 291 // We corrected to a keyword. 292 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 293 Diag(IILoc, diag::err_unknown_typename_suggest) 294 << &II << Corrected; 295 return true; 296 } 297 } 298 299 if (getLangOptions().CPlusPlus) { 300 // See if II is a class template that the user forgot to pass arguments to. 301 UnqualifiedId Name; 302 Name.setIdentifier(&II, IILoc); 303 CXXScopeSpec EmptySS; 304 TemplateTy TemplateResult; 305 bool MemberOfUnknownSpecialization; 306 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 307 Name, ParsedType(), true, TemplateResult, 308 MemberOfUnknownSpecialization) == TNK_Type_template) { 309 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 310 Diag(IILoc, diag::err_template_missing_args) << TplName; 311 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 312 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 313 << TplDecl->getTemplateParameters()->getSourceRange(); 314 } 315 return true; 316 } 317 } 318 319 // FIXME: Should we move the logic that tries to recover from a missing tag 320 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 321 322 if (!SS || (!SS->isSet() && !SS->isInvalid())) 323 Diag(IILoc, diag::err_unknown_typename) << &II; 324 else if (DeclContext *DC = computeDeclContext(*SS, false)) 325 Diag(IILoc, diag::err_typename_nested_not_found) 326 << &II << DC << SS->getRange(); 327 else if (isDependentScopeSpecifier(*SS)) { 328 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 329 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 330 << SourceRange(SS->getRange().getBegin(), IILoc) 331 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 332 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 333 } else { 334 assert(SS && SS->isInvalid() && 335 "Invalid scope specifier has already been diagnosed"); 336 } 337 338 return true; 339} 340 341// Determines the context to return to after temporarily entering a 342// context. This depends in an unnecessarily complicated way on the 343// exact ordering of callbacks from the parser. 344DeclContext *Sema::getContainingDC(DeclContext *DC) { 345 346 // Functions defined inline within classes aren't parsed until we've 347 // finished parsing the top-level class, so the top-level class is 348 // the context we'll need to return to. 349 if (isa<FunctionDecl>(DC)) { 350 DC = DC->getLexicalParent(); 351 352 // A function not defined within a class will always return to its 353 // lexical context. 354 if (!isa<CXXRecordDecl>(DC)) 355 return DC; 356 357 // A C++ inline method/friend is parsed *after* the topmost class 358 // it was declared in is fully parsed ("complete"); the topmost 359 // class is the context we need to return to. 360 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 361 DC = RD; 362 363 // Return the declaration context of the topmost class the inline method is 364 // declared in. 365 return DC; 366 } 367 368 // ObjCMethodDecls are parsed (for some reason) outside the context 369 // of the class. 370 if (isa<ObjCMethodDecl>(DC)) 371 return DC->getLexicalParent()->getLexicalParent(); 372 373 return DC->getLexicalParent(); 374} 375 376void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 377 assert(getContainingDC(DC) == CurContext && 378 "The next DeclContext should be lexically contained in the current one."); 379 CurContext = DC; 380 S->setEntity(DC); 381} 382 383void Sema::PopDeclContext() { 384 assert(CurContext && "DeclContext imbalance!"); 385 386 CurContext = getContainingDC(CurContext); 387 assert(CurContext && "Popped translation unit!"); 388} 389 390/// EnterDeclaratorContext - Used when we must lookup names in the context 391/// of a declarator's nested name specifier. 392/// 393void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 394 // C++0x [basic.lookup.unqual]p13: 395 // A name used in the definition of a static data member of class 396 // X (after the qualified-id of the static member) is looked up as 397 // if the name was used in a member function of X. 398 // C++0x [basic.lookup.unqual]p14: 399 // If a variable member of a namespace is defined outside of the 400 // scope of its namespace then any name used in the definition of 401 // the variable member (after the declarator-id) is looked up as 402 // if the definition of the variable member occurred in its 403 // namespace. 404 // Both of these imply that we should push a scope whose context 405 // is the semantic context of the declaration. We can't use 406 // PushDeclContext here because that context is not necessarily 407 // lexically contained in the current context. Fortunately, 408 // the containing scope should have the appropriate information. 409 410 assert(!S->getEntity() && "scope already has entity"); 411 412#ifndef NDEBUG 413 Scope *Ancestor = S->getParent(); 414 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 415 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 416#endif 417 418 CurContext = DC; 419 S->setEntity(DC); 420} 421 422void Sema::ExitDeclaratorContext(Scope *S) { 423 assert(S->getEntity() == CurContext && "Context imbalance!"); 424 425 // Switch back to the lexical context. The safety of this is 426 // enforced by an assert in EnterDeclaratorContext. 427 Scope *Ancestor = S->getParent(); 428 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 429 CurContext = (DeclContext*) Ancestor->getEntity(); 430 431 // We don't need to do anything with the scope, which is going to 432 // disappear. 433} 434 435/// \brief Determine whether we allow overloading of the function 436/// PrevDecl with another declaration. 437/// 438/// This routine determines whether overloading is possible, not 439/// whether some new function is actually an overload. It will return 440/// true in C++ (where we can always provide overloads) or, as an 441/// extension, in C when the previous function is already an 442/// overloaded function declaration or has the "overloadable" 443/// attribute. 444static bool AllowOverloadingOfFunction(LookupResult &Previous, 445 ASTContext &Context) { 446 if (Context.getLangOptions().CPlusPlus) 447 return true; 448 449 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 450 return true; 451 452 return (Previous.getResultKind() == LookupResult::Found 453 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 454} 455 456/// Add this decl to the scope shadowed decl chains. 457void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 458 // Move up the scope chain until we find the nearest enclosing 459 // non-transparent context. The declaration will be introduced into this 460 // scope. 461 while (S->getEntity() && 462 ((DeclContext *)S->getEntity())->isTransparentContext()) 463 S = S->getParent(); 464 465 // Add scoped declarations into their context, so that they can be 466 // found later. Declarations without a context won't be inserted 467 // into any context. 468 if (AddToContext) 469 CurContext->addDecl(D); 470 471 // Out-of-line definitions shouldn't be pushed into scope in C++. 472 // Out-of-line variable and function definitions shouldn't even in C. 473 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 474 D->isOutOfLine()) 475 return; 476 477 // Template instantiations should also not be pushed into scope. 478 if (isa<FunctionDecl>(D) && 479 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 480 return; 481 482 // If this replaces anything in the current scope, 483 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 484 IEnd = IdResolver.end(); 485 for (; I != IEnd; ++I) { 486 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 487 S->RemoveDecl(*I); 488 IdResolver.RemoveDecl(*I); 489 490 // Should only need to replace one decl. 491 break; 492 } 493 } 494 495 S->AddDecl(D); 496 IdResolver.AddDecl(D); 497} 498 499bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 500 return IdResolver.isDeclInScope(D, Ctx, Context, S); 501} 502 503Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 504 DeclContext *TargetDC = DC->getPrimaryContext(); 505 do { 506 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 507 if (ScopeDC->getPrimaryContext() == TargetDC) 508 return S; 509 } while ((S = S->getParent())); 510 511 return 0; 512} 513 514static bool isOutOfScopePreviousDeclaration(NamedDecl *, 515 DeclContext*, 516 ASTContext&); 517 518/// Filters out lookup results that don't fall within the given scope 519/// as determined by isDeclInScope. 520static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 521 DeclContext *Ctx, Scope *S, 522 bool ConsiderLinkage) { 523 LookupResult::Filter F = R.makeFilter(); 524 while (F.hasNext()) { 525 NamedDecl *D = F.next(); 526 527 if (SemaRef.isDeclInScope(D, Ctx, S)) 528 continue; 529 530 if (ConsiderLinkage && 531 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 532 continue; 533 534 F.erase(); 535 } 536 537 F.done(); 538} 539 540static bool isUsingDecl(NamedDecl *D) { 541 return isa<UsingShadowDecl>(D) || 542 isa<UnresolvedUsingTypenameDecl>(D) || 543 isa<UnresolvedUsingValueDecl>(D); 544} 545 546/// Removes using shadow declarations from the lookup results. 547static void RemoveUsingDecls(LookupResult &R) { 548 LookupResult::Filter F = R.makeFilter(); 549 while (F.hasNext()) 550 if (isUsingDecl(F.next())) 551 F.erase(); 552 553 F.done(); 554} 555 556/// \brief Check for this common pattern: 557/// @code 558/// class S { 559/// S(const S&); // DO NOT IMPLEMENT 560/// void operator=(const S&); // DO NOT IMPLEMENT 561/// }; 562/// @endcode 563static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 564 // FIXME: Should check for private access too but access is set after we get 565 // the decl here. 566 if (D->isThisDeclarationADefinition()) 567 return false; 568 569 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 570 return CD->isCopyConstructor(); 571 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 572 return Method->isCopyAssignmentOperator(); 573 return false; 574} 575 576bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 577 assert(D); 578 579 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 580 return false; 581 582 // Ignore class templates. 583 if (D->getDeclContext()->isDependentContext() || 584 D->getLexicalDeclContext()->isDependentContext()) 585 return false; 586 587 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 588 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 589 return false; 590 591 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 592 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 593 return false; 594 } else { 595 // 'static inline' functions are used in headers; don't warn. 596 if (FD->getStorageClass() == SC_Static && 597 FD->isInlineSpecified()) 598 return false; 599 } 600 601 if (FD->isThisDeclarationADefinition() && 602 Context.DeclMustBeEmitted(FD)) 603 return false; 604 605 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 606 if (!VD->isFileVarDecl() || 607 VD->getType().isConstant(Context) || 608 Context.DeclMustBeEmitted(VD)) 609 return false; 610 611 if (VD->isStaticDataMember() && 612 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 613 return false; 614 615 } else { 616 return false; 617 } 618 619 // Only warn for unused decls internal to the translation unit. 620 if (D->getLinkage() == ExternalLinkage) 621 return false; 622 623 return true; 624} 625 626void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 627 if (!D) 628 return; 629 630 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 631 const FunctionDecl *First = FD->getFirstDeclaration(); 632 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 633 return; // First should already be in the vector. 634 } 635 636 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 637 const VarDecl *First = VD->getFirstDeclaration(); 638 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 639 return; // First should already be in the vector. 640 } 641 642 if (ShouldWarnIfUnusedFileScopedDecl(D)) 643 UnusedFileScopedDecls.push_back(D); 644 } 645 646static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 647 if (D->isInvalidDecl()) 648 return false; 649 650 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 651 return false; 652 653 if (isa<LabelDecl>(D)) 654 return true; 655 656 // White-list anything that isn't a local variable. 657 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 658 !D->getDeclContext()->isFunctionOrMethod()) 659 return false; 660 661 // Types of valid local variables should be complete, so this should succeed. 662 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 663 664 // White-list anything with an __attribute__((unused)) type. 665 QualType Ty = VD->getType(); 666 667 // Only look at the outermost level of typedef. 668 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 669 if (TT->getDecl()->hasAttr<UnusedAttr>()) 670 return false; 671 } 672 673 // If we failed to complete the type for some reason, or if the type is 674 // dependent, don't diagnose the variable. 675 if (Ty->isIncompleteType() || Ty->isDependentType()) 676 return false; 677 678 if (const TagType *TT = Ty->getAs<TagType>()) { 679 const TagDecl *Tag = TT->getDecl(); 680 if (Tag->hasAttr<UnusedAttr>()) 681 return false; 682 683 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 684 // FIXME: Checking for the presence of a user-declared constructor 685 // isn't completely accurate; we'd prefer to check that the initializer 686 // has no side effects. 687 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 688 return false; 689 } 690 } 691 692 // TODO: __attribute__((unused)) templates? 693 } 694 695 return true; 696} 697 698/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 699/// unless they are marked attr(unused). 700void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 701 if (!ShouldDiagnoseUnusedDecl(D)) 702 return; 703 704 unsigned DiagID; 705 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 706 DiagID = diag::warn_unused_exception_param; 707 else if (isa<LabelDecl>(D)) 708 DiagID = diag::warn_unused_label; 709 else 710 DiagID = diag::warn_unused_variable; 711 712 Diag(D->getLocation(), DiagID) << D->getDeclName(); 713} 714 715static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 716 // Verify that we have no forward references left. If so, there was a goto 717 // or address of a label taken, but no definition of it. Label fwd 718 // definitions are indicated with a null substmt. 719 if (L->getStmt() == 0) 720 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 721} 722 723void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 724 if (S->decl_empty()) return; 725 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 726 "Scope shouldn't contain decls!"); 727 728 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 729 I != E; ++I) { 730 Decl *TmpD = (*I); 731 assert(TmpD && "This decl didn't get pushed??"); 732 733 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 734 NamedDecl *D = cast<NamedDecl>(TmpD); 735 736 if (!D->getDeclName()) continue; 737 738 // Diagnose unused variables in this scope. 739 if (!S->hasErrorOccurred()) 740 DiagnoseUnusedDecl(D); 741 742 // If this was a forward reference to a label, verify it was defined. 743 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 744 CheckPoppedLabel(LD, *this); 745 746 // Remove this name from our lexical scope. 747 IdResolver.RemoveDecl(D); 748 } 749} 750 751/// \brief Look for an Objective-C class in the translation unit. 752/// 753/// \param Id The name of the Objective-C class we're looking for. If 754/// typo-correction fixes this name, the Id will be updated 755/// to the fixed name. 756/// 757/// \param IdLoc The location of the name in the translation unit. 758/// 759/// \param TypoCorrection If true, this routine will attempt typo correction 760/// if there is no class with the given name. 761/// 762/// \returns The declaration of the named Objective-C class, or NULL if the 763/// class could not be found. 764ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 765 SourceLocation IdLoc, 766 bool TypoCorrection) { 767 // The third "scope" argument is 0 since we aren't enabling lazy built-in 768 // creation from this context. 769 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 770 771 if (!IDecl && TypoCorrection) { 772 // Perform typo correction at the given location, but only if we 773 // find an Objective-C class name. 774 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 775 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 776 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 777 Diag(IdLoc, diag::err_undef_interface_suggest) 778 << Id << IDecl->getDeclName() 779 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 780 Diag(IDecl->getLocation(), diag::note_previous_decl) 781 << IDecl->getDeclName(); 782 783 Id = IDecl->getIdentifier(); 784 } 785 } 786 787 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 788} 789 790/// getNonFieldDeclScope - Retrieves the innermost scope, starting 791/// from S, where a non-field would be declared. This routine copes 792/// with the difference between C and C++ scoping rules in structs and 793/// unions. For example, the following code is well-formed in C but 794/// ill-formed in C++: 795/// @code 796/// struct S6 { 797/// enum { BAR } e; 798/// }; 799/// 800/// void test_S6() { 801/// struct S6 a; 802/// a.e = BAR; 803/// } 804/// @endcode 805/// For the declaration of BAR, this routine will return a different 806/// scope. The scope S will be the scope of the unnamed enumeration 807/// within S6. In C++, this routine will return the scope associated 808/// with S6, because the enumeration's scope is a transparent 809/// context but structures can contain non-field names. In C, this 810/// routine will return the translation unit scope, since the 811/// enumeration's scope is a transparent context and structures cannot 812/// contain non-field names. 813Scope *Sema::getNonFieldDeclScope(Scope *S) { 814 while (((S->getFlags() & Scope::DeclScope) == 0) || 815 (S->getEntity() && 816 ((DeclContext *)S->getEntity())->isTransparentContext()) || 817 (S->isClassScope() && !getLangOptions().CPlusPlus)) 818 S = S->getParent(); 819 return S; 820} 821 822/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 823/// file scope. lazily create a decl for it. ForRedeclaration is true 824/// if we're creating this built-in in anticipation of redeclaring the 825/// built-in. 826NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 827 Scope *S, bool ForRedeclaration, 828 SourceLocation Loc) { 829 Builtin::ID BID = (Builtin::ID)bid; 830 831 ASTContext::GetBuiltinTypeError Error; 832 QualType R = Context.GetBuiltinType(BID, Error); 833 switch (Error) { 834 case ASTContext::GE_None: 835 // Okay 836 break; 837 838 case ASTContext::GE_Missing_stdio: 839 if (ForRedeclaration) 840 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 841 << Context.BuiltinInfo.GetName(BID); 842 return 0; 843 844 case ASTContext::GE_Missing_setjmp: 845 if (ForRedeclaration) 846 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 847 << Context.BuiltinInfo.GetName(BID); 848 return 0; 849 } 850 851 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 852 Diag(Loc, diag::ext_implicit_lib_function_decl) 853 << Context.BuiltinInfo.GetName(BID) 854 << R; 855 if (Context.BuiltinInfo.getHeaderName(BID) && 856 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 857 != Diagnostic::Ignored) 858 Diag(Loc, diag::note_please_include_header) 859 << Context.BuiltinInfo.getHeaderName(BID) 860 << Context.BuiltinInfo.GetName(BID); 861 } 862 863 FunctionDecl *New = FunctionDecl::Create(Context, 864 Context.getTranslationUnitDecl(), 865 Loc, II, R, /*TInfo=*/0, 866 SC_Extern, 867 SC_None, false, 868 /*hasPrototype=*/true); 869 New->setImplicit(); 870 871 // Create Decl objects for each parameter, adding them to the 872 // FunctionDecl. 873 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 874 llvm::SmallVector<ParmVarDecl*, 16> Params; 875 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 876 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 877 FT->getArgType(i), /*TInfo=*/0, 878 SC_None, SC_None, 0)); 879 New->setParams(Params.data(), Params.size()); 880 } 881 882 AddKnownFunctionAttributes(New); 883 884 // TUScope is the translation-unit scope to insert this function into. 885 // FIXME: This is hideous. We need to teach PushOnScopeChains to 886 // relate Scopes to DeclContexts, and probably eliminate CurContext 887 // entirely, but we're not there yet. 888 DeclContext *SavedContext = CurContext; 889 CurContext = Context.getTranslationUnitDecl(); 890 PushOnScopeChains(New, TUScope); 891 CurContext = SavedContext; 892 return New; 893} 894 895/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 896/// same name and scope as a previous declaration 'Old'. Figure out 897/// how to resolve this situation, merging decls or emitting 898/// diagnostics as appropriate. If there was an error, set New to be invalid. 899/// 900void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 901 // If the new decl is known invalid already, don't bother doing any 902 // merging checks. 903 if (New->isInvalidDecl()) return; 904 905 // Allow multiple definitions for ObjC built-in typedefs. 906 // FIXME: Verify the underlying types are equivalent! 907 if (getLangOptions().ObjC1) { 908 const IdentifierInfo *TypeID = New->getIdentifier(); 909 switch (TypeID->getLength()) { 910 default: break; 911 case 2: 912 if (!TypeID->isStr("id")) 913 break; 914 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 915 // Install the built-in type for 'id', ignoring the current definition. 916 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 917 return; 918 case 5: 919 if (!TypeID->isStr("Class")) 920 break; 921 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 922 // Install the built-in type for 'Class', ignoring the current definition. 923 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 924 return; 925 case 3: 926 if (!TypeID->isStr("SEL")) 927 break; 928 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 929 // Install the built-in type for 'SEL', ignoring the current definition. 930 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 931 return; 932 case 8: 933 if (!TypeID->isStr("Protocol")) 934 break; 935 Context.setObjCProtoType(New->getUnderlyingType()); 936 return; 937 } 938 // Fall through - the typedef name was not a builtin type. 939 } 940 941 // Verify the old decl was also a type. 942 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 943 if (!Old) { 944 Diag(New->getLocation(), diag::err_redefinition_different_kind) 945 << New->getDeclName(); 946 947 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 948 if (OldD->getLocation().isValid()) 949 Diag(OldD->getLocation(), diag::note_previous_definition); 950 951 return New->setInvalidDecl(); 952 } 953 954 // If the old declaration is invalid, just give up here. 955 if (Old->isInvalidDecl()) 956 return New->setInvalidDecl(); 957 958 // Determine the "old" type we'll use for checking and diagnostics. 959 QualType OldType; 960 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 961 OldType = OldTypedef->getUnderlyingType(); 962 else 963 OldType = Context.getTypeDeclType(Old); 964 965 // If the typedef types are not identical, reject them in all languages and 966 // with any extensions enabled. 967 968 if (OldType != New->getUnderlyingType() && 969 Context.getCanonicalType(OldType) != 970 Context.getCanonicalType(New->getUnderlyingType())) { 971 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 972 << New->getUnderlyingType() << OldType; 973 if (Old->getLocation().isValid()) 974 Diag(Old->getLocation(), diag::note_previous_definition); 975 return New->setInvalidDecl(); 976 } 977 978 // The types match. Link up the redeclaration chain if the old 979 // declaration was a typedef. 980 // FIXME: this is a potential source of wierdness if the type 981 // spellings don't match exactly. 982 if (isa<TypedefDecl>(Old)) 983 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 984 985 if (getLangOptions().Microsoft) 986 return; 987 988 if (getLangOptions().CPlusPlus) { 989 // C++ [dcl.typedef]p2: 990 // In a given non-class scope, a typedef specifier can be used to 991 // redefine the name of any type declared in that scope to refer 992 // to the type to which it already refers. 993 if (!isa<CXXRecordDecl>(CurContext)) 994 return; 995 996 // C++0x [dcl.typedef]p4: 997 // In a given class scope, a typedef specifier can be used to redefine 998 // any class-name declared in that scope that is not also a typedef-name 999 // to refer to the type to which it already refers. 1000 // 1001 // This wording came in via DR424, which was a correction to the 1002 // wording in DR56, which accidentally banned code like: 1003 // 1004 // struct S { 1005 // typedef struct A { } A; 1006 // }; 1007 // 1008 // in the C++03 standard. We implement the C++0x semantics, which 1009 // allow the above but disallow 1010 // 1011 // struct S { 1012 // typedef int I; 1013 // typedef int I; 1014 // }; 1015 // 1016 // since that was the intent of DR56. 1017 if (!isa<TypedefDecl >(Old)) 1018 return; 1019 1020 Diag(New->getLocation(), diag::err_redefinition) 1021 << New->getDeclName(); 1022 Diag(Old->getLocation(), diag::note_previous_definition); 1023 return New->setInvalidDecl(); 1024 } 1025 1026 // If we have a redefinition of a typedef in C, emit a warning. This warning 1027 // is normally mapped to an error, but can be controlled with 1028 // -Wtypedef-redefinition. If either the original or the redefinition is 1029 // in a system header, don't emit this for compatibility with GCC. 1030 if (getDiagnostics().getSuppressSystemWarnings() && 1031 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1032 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1033 return; 1034 1035 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1036 << New->getDeclName(); 1037 Diag(Old->getLocation(), diag::note_previous_definition); 1038 return; 1039} 1040 1041/// DeclhasAttr - returns true if decl Declaration already has the target 1042/// attribute. 1043static bool 1044DeclHasAttr(const Decl *D, const Attr *A) { 1045 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1046 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1047 if ((*i)->getKind() == A->getKind()) { 1048 // FIXME: Don't hardcode this check 1049 if (OA && isa<OwnershipAttr>(*i)) 1050 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1051 return true; 1052 } 1053 1054 return false; 1055} 1056 1057/// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 1058static void mergeDeclAttributes(Decl *newDecl, const Decl *oldDecl, 1059 ASTContext &C) { 1060 if (!oldDecl->hasAttrs()) 1061 return; 1062 1063 bool foundAny = newDecl->hasAttrs(); 1064 1065 // Ensure that any moving of objects within the allocated map is done before 1066 // we process them. 1067 if (!foundAny) newDecl->setAttrs(AttrVec()); 1068 1069 for (specific_attr_iterator<InheritableAttr> 1070 i = oldDecl->specific_attr_begin<InheritableAttr>(), 1071 e = oldDecl->specific_attr_end<InheritableAttr>(); i != e; ++i) { 1072 if (!DeclHasAttr(newDecl, *i)) { 1073 InheritableAttr *newAttr = cast<InheritableAttr>((*i)->clone(C)); 1074 newAttr->setInherited(true); 1075 newDecl->addAttr(newAttr); 1076 foundAny = true; 1077 } 1078 } 1079 1080 if (!foundAny) newDecl->dropAttrs(); 1081} 1082 1083/// mergeParamDeclAttributes - Copy attributes from the old parameter 1084/// to the new one. 1085static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 1086 const ParmVarDecl *oldDecl, 1087 ASTContext &C) { 1088 if (!oldDecl->hasAttrs()) 1089 return; 1090 1091 bool foundAny = newDecl->hasAttrs(); 1092 1093 // Ensure that any moving of objects within the allocated map is 1094 // done before we process them. 1095 if (!foundAny) newDecl->setAttrs(AttrVec()); 1096 1097 for (specific_attr_iterator<InheritableParamAttr> 1098 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 1099 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 1100 if (!DeclHasAttr(newDecl, *i)) { 1101 InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(C)); 1102 newAttr->setInherited(true); 1103 newDecl->addAttr(newAttr); 1104 foundAny = true; 1105 } 1106 } 1107 1108 if (!foundAny) newDecl->dropAttrs(); 1109} 1110 1111namespace { 1112 1113/// Used in MergeFunctionDecl to keep track of function parameters in 1114/// C. 1115struct GNUCompatibleParamWarning { 1116 ParmVarDecl *OldParm; 1117 ParmVarDecl *NewParm; 1118 QualType PromotedType; 1119}; 1120 1121} 1122 1123/// getSpecialMember - get the special member enum for a method. 1124Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1125 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1126 if (Ctor->isCopyConstructor()) 1127 return Sema::CXXCopyConstructor; 1128 1129 return Sema::CXXConstructor; 1130 } 1131 1132 if (isa<CXXDestructorDecl>(MD)) 1133 return Sema::CXXDestructor; 1134 1135 assert(MD->isCopyAssignmentOperator() && 1136 "Must have copy assignment operator"); 1137 return Sema::CXXCopyAssignment; 1138} 1139 1140/// canRedefineFunction - checks if a function can be redefined. Currently, 1141/// only extern inline functions can be redefined, and even then only in 1142/// GNU89 mode. 1143static bool canRedefineFunction(const FunctionDecl *FD, 1144 const LangOptions& LangOpts) { 1145 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1146 FD->isInlineSpecified() && 1147 FD->getStorageClass() == SC_Extern); 1148} 1149 1150/// MergeFunctionDecl - We just parsed a function 'New' from 1151/// declarator D which has the same name and scope as a previous 1152/// declaration 'Old'. Figure out how to resolve this situation, 1153/// merging decls or emitting diagnostics as appropriate. 1154/// 1155/// In C++, New and Old must be declarations that are not 1156/// overloaded. Use IsOverload to determine whether New and Old are 1157/// overloaded, and to select the Old declaration that New should be 1158/// merged with. 1159/// 1160/// Returns true if there was an error, false otherwise. 1161bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1162 // Verify the old decl was also a function. 1163 FunctionDecl *Old = 0; 1164 if (FunctionTemplateDecl *OldFunctionTemplate 1165 = dyn_cast<FunctionTemplateDecl>(OldD)) 1166 Old = OldFunctionTemplate->getTemplatedDecl(); 1167 else 1168 Old = dyn_cast<FunctionDecl>(OldD); 1169 if (!Old) { 1170 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1171 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1172 Diag(Shadow->getTargetDecl()->getLocation(), 1173 diag::note_using_decl_target); 1174 Diag(Shadow->getUsingDecl()->getLocation(), 1175 diag::note_using_decl) << 0; 1176 return true; 1177 } 1178 1179 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1180 << New->getDeclName(); 1181 Diag(OldD->getLocation(), diag::note_previous_definition); 1182 return true; 1183 } 1184 1185 // Determine whether the previous declaration was a definition, 1186 // implicit declaration, or a declaration. 1187 diag::kind PrevDiag; 1188 if (Old->isThisDeclarationADefinition()) 1189 PrevDiag = diag::note_previous_definition; 1190 else if (Old->isImplicit()) 1191 PrevDiag = diag::note_previous_implicit_declaration; 1192 else 1193 PrevDiag = diag::note_previous_declaration; 1194 1195 QualType OldQType = Context.getCanonicalType(Old->getType()); 1196 QualType NewQType = Context.getCanonicalType(New->getType()); 1197 1198 // Don't complain about this if we're in GNU89 mode and the old function 1199 // is an extern inline function. 1200 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1201 New->getStorageClass() == SC_Static && 1202 Old->getStorageClass() != SC_Static && 1203 !canRedefineFunction(Old, getLangOptions())) { 1204 Diag(New->getLocation(), diag::err_static_non_static) 1205 << New; 1206 Diag(Old->getLocation(), PrevDiag); 1207 return true; 1208 } 1209 1210 // If a function is first declared with a calling convention, but is 1211 // later declared or defined without one, the second decl assumes the 1212 // calling convention of the first. 1213 // 1214 // For the new decl, we have to look at the NON-canonical type to tell the 1215 // difference between a function that really doesn't have a calling 1216 // convention and one that is declared cdecl. That's because in 1217 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1218 // because it is the default calling convention. 1219 // 1220 // Note also that we DO NOT return at this point, because we still have 1221 // other tests to run. 1222 const FunctionType *OldType = cast<FunctionType>(OldQType); 1223 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1224 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1225 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1226 bool RequiresAdjustment = false; 1227 if (OldTypeInfo.getCC() != CC_Default && 1228 NewTypeInfo.getCC() == CC_Default) { 1229 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1230 RequiresAdjustment = true; 1231 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1232 NewTypeInfo.getCC())) { 1233 // Calling conventions really aren't compatible, so complain. 1234 Diag(New->getLocation(), diag::err_cconv_change) 1235 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1236 << (OldTypeInfo.getCC() == CC_Default) 1237 << (OldTypeInfo.getCC() == CC_Default ? "" : 1238 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1239 Diag(Old->getLocation(), diag::note_previous_declaration); 1240 return true; 1241 } 1242 1243 // FIXME: diagnose the other way around? 1244 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1245 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1246 RequiresAdjustment = true; 1247 } 1248 1249 // Merge regparm attribute. 1250 if (OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1251 if (NewTypeInfo.getRegParm()) { 1252 Diag(New->getLocation(), diag::err_regparm_mismatch) 1253 << NewType->getRegParmType() 1254 << OldType->getRegParmType(); 1255 Diag(Old->getLocation(), diag::note_previous_declaration); 1256 return true; 1257 } 1258 1259 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1260 RequiresAdjustment = true; 1261 } 1262 1263 if (RequiresAdjustment) { 1264 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1265 New->setType(QualType(NewType, 0)); 1266 NewQType = Context.getCanonicalType(New->getType()); 1267 } 1268 1269 if (getLangOptions().CPlusPlus) { 1270 // (C++98 13.1p2): 1271 // Certain function declarations cannot be overloaded: 1272 // -- Function declarations that differ only in the return type 1273 // cannot be overloaded. 1274 QualType OldReturnType = OldType->getResultType(); 1275 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1276 QualType ResQT; 1277 if (OldReturnType != NewReturnType) { 1278 if (NewReturnType->isObjCObjectPointerType() 1279 && OldReturnType->isObjCObjectPointerType()) 1280 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1281 if (ResQT.isNull()) { 1282 if (New->isCXXClassMember() && New->isOutOfLine()) 1283 Diag(New->getLocation(), 1284 diag::err_member_def_does_not_match_ret_type) << New; 1285 else 1286 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1287 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1288 return true; 1289 } 1290 else 1291 NewQType = ResQT; 1292 } 1293 1294 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1295 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1296 if (OldMethod && NewMethod) { 1297 // Preserve triviality. 1298 NewMethod->setTrivial(OldMethod->isTrivial()); 1299 1300 bool isFriend = NewMethod->getFriendObjectKind(); 1301 1302 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1303 // -- Member function declarations with the same name and the 1304 // same parameter types cannot be overloaded if any of them 1305 // is a static member function declaration. 1306 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1307 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1308 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1309 return true; 1310 } 1311 1312 // C++ [class.mem]p1: 1313 // [...] A member shall not be declared twice in the 1314 // member-specification, except that a nested class or member 1315 // class template can be declared and then later defined. 1316 unsigned NewDiag; 1317 if (isa<CXXConstructorDecl>(OldMethod)) 1318 NewDiag = diag::err_constructor_redeclared; 1319 else if (isa<CXXDestructorDecl>(NewMethod)) 1320 NewDiag = diag::err_destructor_redeclared; 1321 else if (isa<CXXConversionDecl>(NewMethod)) 1322 NewDiag = diag::err_conv_function_redeclared; 1323 else 1324 NewDiag = diag::err_member_redeclared; 1325 1326 Diag(New->getLocation(), NewDiag); 1327 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1328 1329 // Complain if this is an explicit declaration of a special 1330 // member that was initially declared implicitly. 1331 // 1332 // As an exception, it's okay to befriend such methods in order 1333 // to permit the implicit constructor/destructor/operator calls. 1334 } else if (OldMethod->isImplicit()) { 1335 if (isFriend) { 1336 NewMethod->setImplicit(); 1337 } else { 1338 Diag(NewMethod->getLocation(), 1339 diag::err_definition_of_implicitly_declared_member) 1340 << New << getSpecialMember(OldMethod); 1341 return true; 1342 } 1343 } 1344 } 1345 1346 // (C++98 8.3.5p3): 1347 // All declarations for a function shall agree exactly in both the 1348 // return type and the parameter-type-list. 1349 // We also want to respect all the extended bits except noreturn. 1350 1351 // noreturn should now match unless the old type info didn't have it. 1352 QualType OldQTypeForComparison = OldQType; 1353 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1354 assert(OldQType == QualType(OldType, 0)); 1355 const FunctionType *OldTypeForComparison 1356 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1357 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1358 assert(OldQTypeForComparison.isCanonical()); 1359 } 1360 1361 if (OldQTypeForComparison == NewQType) 1362 return MergeCompatibleFunctionDecls(New, Old); 1363 1364 // Fall through for conflicting redeclarations and redefinitions. 1365 } 1366 1367 // C: Function types need to be compatible, not identical. This handles 1368 // duplicate function decls like "void f(int); void f(enum X);" properly. 1369 if (!getLangOptions().CPlusPlus && 1370 Context.typesAreCompatible(OldQType, NewQType)) { 1371 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1372 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1373 const FunctionProtoType *OldProto = 0; 1374 if (isa<FunctionNoProtoType>(NewFuncType) && 1375 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1376 // The old declaration provided a function prototype, but the 1377 // new declaration does not. Merge in the prototype. 1378 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1379 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1380 OldProto->arg_type_end()); 1381 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1382 ParamTypes.data(), ParamTypes.size(), 1383 OldProto->getExtProtoInfo()); 1384 New->setType(NewQType); 1385 New->setHasInheritedPrototype(); 1386 1387 // Synthesize a parameter for each argument type. 1388 llvm::SmallVector<ParmVarDecl*, 16> Params; 1389 for (FunctionProtoType::arg_type_iterator 1390 ParamType = OldProto->arg_type_begin(), 1391 ParamEnd = OldProto->arg_type_end(); 1392 ParamType != ParamEnd; ++ParamType) { 1393 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1394 SourceLocation(), 0, 1395 *ParamType, /*TInfo=*/0, 1396 SC_None, SC_None, 1397 0); 1398 Param->setImplicit(); 1399 Params.push_back(Param); 1400 } 1401 1402 New->setParams(Params.data(), Params.size()); 1403 } 1404 1405 return MergeCompatibleFunctionDecls(New, Old); 1406 } 1407 1408 // GNU C permits a K&R definition to follow a prototype declaration 1409 // if the declared types of the parameters in the K&R definition 1410 // match the types in the prototype declaration, even when the 1411 // promoted types of the parameters from the K&R definition differ 1412 // from the types in the prototype. GCC then keeps the types from 1413 // the prototype. 1414 // 1415 // If a variadic prototype is followed by a non-variadic K&R definition, 1416 // the K&R definition becomes variadic. This is sort of an edge case, but 1417 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1418 // C99 6.9.1p8. 1419 if (!getLangOptions().CPlusPlus && 1420 Old->hasPrototype() && !New->hasPrototype() && 1421 New->getType()->getAs<FunctionProtoType>() && 1422 Old->getNumParams() == New->getNumParams()) { 1423 llvm::SmallVector<QualType, 16> ArgTypes; 1424 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1425 const FunctionProtoType *OldProto 1426 = Old->getType()->getAs<FunctionProtoType>(); 1427 const FunctionProtoType *NewProto 1428 = New->getType()->getAs<FunctionProtoType>(); 1429 1430 // Determine whether this is the GNU C extension. 1431 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1432 NewProto->getResultType()); 1433 bool LooseCompatible = !MergedReturn.isNull(); 1434 for (unsigned Idx = 0, End = Old->getNumParams(); 1435 LooseCompatible && Idx != End; ++Idx) { 1436 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1437 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1438 if (Context.typesAreCompatible(OldParm->getType(), 1439 NewProto->getArgType(Idx))) { 1440 ArgTypes.push_back(NewParm->getType()); 1441 } else if (Context.typesAreCompatible(OldParm->getType(), 1442 NewParm->getType(), 1443 /*CompareUnqualified=*/true)) { 1444 GNUCompatibleParamWarning Warn 1445 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1446 Warnings.push_back(Warn); 1447 ArgTypes.push_back(NewParm->getType()); 1448 } else 1449 LooseCompatible = false; 1450 } 1451 1452 if (LooseCompatible) { 1453 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1454 Diag(Warnings[Warn].NewParm->getLocation(), 1455 diag::ext_param_promoted_not_compatible_with_prototype) 1456 << Warnings[Warn].PromotedType 1457 << Warnings[Warn].OldParm->getType(); 1458 if (Warnings[Warn].OldParm->getLocation().isValid()) 1459 Diag(Warnings[Warn].OldParm->getLocation(), 1460 diag::note_previous_declaration); 1461 } 1462 1463 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1464 ArgTypes.size(), 1465 OldProto->getExtProtoInfo())); 1466 return MergeCompatibleFunctionDecls(New, Old); 1467 } 1468 1469 // Fall through to diagnose conflicting types. 1470 } 1471 1472 // A function that has already been declared has been redeclared or defined 1473 // with a different type- show appropriate diagnostic 1474 if (unsigned BuiltinID = Old->getBuiltinID()) { 1475 // The user has declared a builtin function with an incompatible 1476 // signature. 1477 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1478 // The function the user is redeclaring is a library-defined 1479 // function like 'malloc' or 'printf'. Warn about the 1480 // redeclaration, then pretend that we don't know about this 1481 // library built-in. 1482 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1483 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1484 << Old << Old->getType(); 1485 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1486 Old->setInvalidDecl(); 1487 return false; 1488 } 1489 1490 PrevDiag = diag::note_previous_builtin_declaration; 1491 } 1492 1493 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1494 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1495 return true; 1496} 1497 1498/// \brief Completes the merge of two function declarations that are 1499/// known to be compatible. 1500/// 1501/// This routine handles the merging of attributes and other 1502/// properties of function declarations form the old declaration to 1503/// the new declaration, once we know that New is in fact a 1504/// redeclaration of Old. 1505/// 1506/// \returns false 1507bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1508 // Merge the attributes 1509 mergeDeclAttributes(New, Old, Context); 1510 1511 // Merge the storage class. 1512 if (Old->getStorageClass() != SC_Extern && 1513 Old->getStorageClass() != SC_None) 1514 New->setStorageClass(Old->getStorageClass()); 1515 1516 // Merge "pure" flag. 1517 if (Old->isPure()) 1518 New->setPure(); 1519 1520 // Merge the "deleted" flag. 1521 if (Old->isDeleted()) 1522 New->setDeleted(); 1523 1524 // Merge attributes from the parameters. These can mismatch with K&R 1525 // declarations. 1526 if (New->getNumParams() == Old->getNumParams()) 1527 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1528 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1529 Context); 1530 1531 if (getLangOptions().CPlusPlus) 1532 return MergeCXXFunctionDecl(New, Old); 1533 1534 return false; 1535} 1536 1537void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1538 const ObjCMethodDecl *oldMethod) { 1539 // Merge the attributes. 1540 mergeDeclAttributes(newMethod, oldMethod, Context); 1541 1542 // Merge attributes from the parameters. 1543 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1544 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1545 ni != ne; ++ni, ++oi) 1546 mergeParamDeclAttributes(*ni, *oi, Context); 1547} 1548 1549/// MergeVarDecl - We parsed a variable 'New' which has the same name and scope 1550/// as a previous declaration 'Old'. Figure out how to merge their types, 1551/// emitting diagnostics as appropriate. 1552/// 1553/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1554/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1555/// check them before the initializer is attached. 1556/// 1557void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1558 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1559 return; 1560 1561 QualType MergedT; 1562 if (getLangOptions().CPlusPlus) { 1563 AutoType *AT = New->getType()->getContainedAutoType(); 1564 if (AT && !AT->isDeduced()) { 1565 // We don't know what the new type is until the initializer is attached. 1566 return; 1567 } else if (Context.hasSameType(New->getType(), Old->getType())) 1568 return; 1569 // C++ [basic.link]p10: 1570 // [...] the types specified by all declarations referring to a given 1571 // object or function shall be identical, except that declarations for an 1572 // array object can specify array types that differ by the presence or 1573 // absence of a major array bound (8.3.4). 1574 else if (Old->getType()->isIncompleteArrayType() && 1575 New->getType()->isArrayType()) { 1576 CanQual<ArrayType> OldArray 1577 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1578 CanQual<ArrayType> NewArray 1579 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1580 if (OldArray->getElementType() == NewArray->getElementType()) 1581 MergedT = New->getType(); 1582 } else if (Old->getType()->isArrayType() && 1583 New->getType()->isIncompleteArrayType()) { 1584 CanQual<ArrayType> OldArray 1585 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1586 CanQual<ArrayType> NewArray 1587 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1588 if (OldArray->getElementType() == NewArray->getElementType()) 1589 MergedT = Old->getType(); 1590 } else if (New->getType()->isObjCObjectPointerType() 1591 && Old->getType()->isObjCObjectPointerType()) { 1592 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1593 Old->getType()); 1594 } 1595 } else { 1596 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1597 } 1598 if (MergedT.isNull()) { 1599 Diag(New->getLocation(), diag::err_redefinition_different_type) 1600 << New->getDeclName(); 1601 Diag(Old->getLocation(), diag::note_previous_definition); 1602 return New->setInvalidDecl(); 1603 } 1604 New->setType(MergedT); 1605} 1606 1607/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1608/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1609/// situation, merging decls or emitting diagnostics as appropriate. 1610/// 1611/// Tentative definition rules (C99 6.9.2p2) are checked by 1612/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1613/// definitions here, since the initializer hasn't been attached. 1614/// 1615void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1616 // If the new decl is already invalid, don't do any other checking. 1617 if (New->isInvalidDecl()) 1618 return; 1619 1620 // Verify the old decl was also a variable. 1621 VarDecl *Old = 0; 1622 if (!Previous.isSingleResult() || 1623 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1624 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1625 << New->getDeclName(); 1626 Diag(Previous.getRepresentativeDecl()->getLocation(), 1627 diag::note_previous_definition); 1628 return New->setInvalidDecl(); 1629 } 1630 1631 // C++ [class.mem]p1: 1632 // A member shall not be declared twice in the member-specification [...] 1633 // 1634 // Here, we need only consider static data members. 1635 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1636 Diag(New->getLocation(), diag::err_duplicate_member) 1637 << New->getIdentifier(); 1638 Diag(Old->getLocation(), diag::note_previous_declaration); 1639 New->setInvalidDecl(); 1640 } 1641 1642 mergeDeclAttributes(New, Old, Context); 1643 1644 // Merge the types. 1645 MergeVarDeclTypes(New, Old); 1646 if (New->isInvalidDecl()) 1647 return; 1648 1649 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1650 if (New->getStorageClass() == SC_Static && 1651 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1652 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1653 Diag(Old->getLocation(), diag::note_previous_definition); 1654 return New->setInvalidDecl(); 1655 } 1656 // C99 6.2.2p4: 1657 // For an identifier declared with the storage-class specifier 1658 // extern in a scope in which a prior declaration of that 1659 // identifier is visible,23) if the prior declaration specifies 1660 // internal or external linkage, the linkage of the identifier at 1661 // the later declaration is the same as the linkage specified at 1662 // the prior declaration. If no prior declaration is visible, or 1663 // if the prior declaration specifies no linkage, then the 1664 // identifier has external linkage. 1665 if (New->hasExternalStorage() && Old->hasLinkage()) 1666 /* Okay */; 1667 else if (New->getStorageClass() != SC_Static && 1668 Old->getStorageClass() == SC_Static) { 1669 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1670 Diag(Old->getLocation(), diag::note_previous_definition); 1671 return New->setInvalidDecl(); 1672 } 1673 1674 // Check if extern is followed by non-extern and vice-versa. 1675 if (New->hasExternalStorage() && 1676 !Old->hasLinkage() && Old->isLocalVarDecl()) { 1677 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 1678 Diag(Old->getLocation(), diag::note_previous_definition); 1679 return New->setInvalidDecl(); 1680 } 1681 if (Old->hasExternalStorage() && 1682 !New->hasLinkage() && New->isLocalVarDecl()) { 1683 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 1684 Diag(Old->getLocation(), diag::note_previous_definition); 1685 return New->setInvalidDecl(); 1686 } 1687 1688 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1689 1690 // FIXME: The test for external storage here seems wrong? We still 1691 // need to check for mismatches. 1692 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1693 // Don't complain about out-of-line definitions of static members. 1694 !(Old->getLexicalDeclContext()->isRecord() && 1695 !New->getLexicalDeclContext()->isRecord())) { 1696 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1697 Diag(Old->getLocation(), diag::note_previous_definition); 1698 return New->setInvalidDecl(); 1699 } 1700 1701 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1702 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1703 Diag(Old->getLocation(), diag::note_previous_definition); 1704 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1705 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1706 Diag(Old->getLocation(), diag::note_previous_definition); 1707 } 1708 1709 // C++ doesn't have tentative definitions, so go right ahead and check here. 1710 const VarDecl *Def; 1711 if (getLangOptions().CPlusPlus && 1712 New->isThisDeclarationADefinition() == VarDecl::Definition && 1713 (Def = Old->getDefinition())) { 1714 Diag(New->getLocation(), diag::err_redefinition) 1715 << New->getDeclName(); 1716 Diag(Def->getLocation(), diag::note_previous_definition); 1717 New->setInvalidDecl(); 1718 return; 1719 } 1720 // c99 6.2.2 P4. 1721 // For an identifier declared with the storage-class specifier extern in a 1722 // scope in which a prior declaration of that identifier is visible, if 1723 // the prior declaration specifies internal or external linkage, the linkage 1724 // of the identifier at the later declaration is the same as the linkage 1725 // specified at the prior declaration. 1726 // FIXME. revisit this code. 1727 if (New->hasExternalStorage() && 1728 Old->getLinkage() == InternalLinkage && 1729 New->getDeclContext() == Old->getDeclContext()) 1730 New->setStorageClass(Old->getStorageClass()); 1731 1732 // Keep a chain of previous declarations. 1733 New->setPreviousDeclaration(Old); 1734 1735 // Inherit access appropriately. 1736 New->setAccess(Old->getAccess()); 1737} 1738 1739/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1740/// no declarator (e.g. "struct foo;") is parsed. 1741Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1742 DeclSpec &DS) { 1743 // FIXME: Error on inline/virtual/explicit 1744 // FIXME: Warn on useless __thread 1745 // FIXME: Warn on useless const/volatile 1746 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1747 // FIXME: Warn on useless attributes 1748 Decl *TagD = 0; 1749 TagDecl *Tag = 0; 1750 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1751 DS.getTypeSpecType() == DeclSpec::TST_struct || 1752 DS.getTypeSpecType() == DeclSpec::TST_union || 1753 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1754 TagD = DS.getRepAsDecl(); 1755 1756 if (!TagD) // We probably had an error 1757 return 0; 1758 1759 // Note that the above type specs guarantee that the 1760 // type rep is a Decl, whereas in many of the others 1761 // it's a Type. 1762 Tag = dyn_cast<TagDecl>(TagD); 1763 } 1764 1765 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1766 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1767 // or incomplete types shall not be restrict-qualified." 1768 if (TypeQuals & DeclSpec::TQ_restrict) 1769 Diag(DS.getRestrictSpecLoc(), 1770 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1771 << DS.getSourceRange(); 1772 } 1773 1774 if (DS.isFriendSpecified()) { 1775 // If we're dealing with a decl but not a TagDecl, assume that 1776 // whatever routines created it handled the friendship aspect. 1777 if (TagD && !Tag) 1778 return 0; 1779 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1780 } 1781 1782 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1783 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 1784 1785 if (!Record->getDeclName() && Record->isDefinition() && 1786 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1787 if (getLangOptions().CPlusPlus || 1788 Record->getDeclContext()->isRecord()) 1789 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1790 1791 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1792 << DS.getSourceRange(); 1793 } 1794 } 1795 1796 // Check for Microsoft C extension: anonymous struct. 1797 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 1798 CurContext->isRecord() && 1799 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 1800 // Handle 2 kinds of anonymous struct: 1801 // struct STRUCT; 1802 // and 1803 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 1804 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 1805 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 1806 (DS.getTypeSpecType() == DeclSpec::TST_typename && 1807 DS.getRepAsType().get()->isStructureType())) { 1808 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 1809 << DS.getSourceRange(); 1810 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 1811 } 1812 } 1813 1814 if (getLangOptions().CPlusPlus && 1815 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1816 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1817 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1818 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1819 Diag(Enum->getLocation(), diag::ext_no_declarators) 1820 << DS.getSourceRange(); 1821 1822 if (!DS.isMissingDeclaratorOk() && 1823 DS.getTypeSpecType() != DeclSpec::TST_error) { 1824 // Warn about typedefs of enums without names, since this is an 1825 // extension in both Microsoft and GNU. 1826 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1827 Tag && isa<EnumDecl>(Tag)) { 1828 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1829 << DS.getSourceRange(); 1830 return Tag; 1831 } 1832 1833 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1834 << DS.getSourceRange(); 1835 } 1836 1837 return TagD; 1838} 1839 1840/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1841/// builds a statement for it and returns it so it is evaluated. 1842StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1843 StmtResult R; 1844 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1845 Expr *Exp = DS.getRepAsExpr(); 1846 QualType Ty = Exp->getType(); 1847 if (Ty->isPointerType()) { 1848 do 1849 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1850 while (Ty->isPointerType()); 1851 } 1852 if (Ty->isVariableArrayType()) { 1853 R = ActOnExprStmt(MakeFullExpr(Exp)); 1854 } 1855 } 1856 return R; 1857} 1858 1859/// We are trying to inject an anonymous member into the given scope; 1860/// check if there's an existing declaration that can't be overloaded. 1861/// 1862/// \return true if this is a forbidden redeclaration 1863static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1864 Scope *S, 1865 DeclContext *Owner, 1866 DeclarationName Name, 1867 SourceLocation NameLoc, 1868 unsigned diagnostic) { 1869 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1870 Sema::ForRedeclaration); 1871 if (!SemaRef.LookupName(R, S)) return false; 1872 1873 if (R.getAsSingle<TagDecl>()) 1874 return false; 1875 1876 // Pick a representative declaration. 1877 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1878 assert(PrevDecl && "Expected a non-null Decl"); 1879 1880 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1881 return false; 1882 1883 SemaRef.Diag(NameLoc, diagnostic) << Name; 1884 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1885 1886 return true; 1887} 1888 1889/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1890/// anonymous struct or union AnonRecord into the owning context Owner 1891/// and scope S. This routine will be invoked just after we realize 1892/// that an unnamed union or struct is actually an anonymous union or 1893/// struct, e.g., 1894/// 1895/// @code 1896/// union { 1897/// int i; 1898/// float f; 1899/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1900/// // f into the surrounding scope.x 1901/// @endcode 1902/// 1903/// This routine is recursive, injecting the names of nested anonymous 1904/// structs/unions into the owning context and scope as well. 1905static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1906 DeclContext *Owner, 1907 RecordDecl *AnonRecord, 1908 AccessSpecifier AS, 1909 llvm::SmallVector<NamedDecl*, 2> &Chaining, 1910 bool MSAnonStruct) { 1911 unsigned diagKind 1912 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1913 : diag::err_anonymous_struct_member_redecl; 1914 1915 bool Invalid = false; 1916 1917 // Look every FieldDecl and IndirectFieldDecl with a name. 1918 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 1919 DEnd = AnonRecord->decls_end(); 1920 D != DEnd; ++D) { 1921 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 1922 cast<NamedDecl>(*D)->getDeclName()) { 1923 ValueDecl *VD = cast<ValueDecl>(*D); 1924 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 1925 VD->getLocation(), diagKind)) { 1926 // C++ [class.union]p2: 1927 // The names of the members of an anonymous union shall be 1928 // distinct from the names of any other entity in the 1929 // scope in which the anonymous union is declared. 1930 Invalid = true; 1931 } else { 1932 // C++ [class.union]p2: 1933 // For the purpose of name lookup, after the anonymous union 1934 // definition, the members of the anonymous union are 1935 // considered to have been defined in the scope in which the 1936 // anonymous union is declared. 1937 unsigned OldChainingSize = Chaining.size(); 1938 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 1939 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 1940 PE = IF->chain_end(); PI != PE; ++PI) 1941 Chaining.push_back(*PI); 1942 else 1943 Chaining.push_back(VD); 1944 1945 assert(Chaining.size() >= 2); 1946 NamedDecl **NamedChain = 1947 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 1948 for (unsigned i = 0; i < Chaining.size(); i++) 1949 NamedChain[i] = Chaining[i]; 1950 1951 IndirectFieldDecl* IndirectField = 1952 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 1953 VD->getIdentifier(), VD->getType(), 1954 NamedChain, Chaining.size()); 1955 1956 IndirectField->setAccess(AS); 1957 IndirectField->setImplicit(); 1958 SemaRef.PushOnScopeChains(IndirectField, S); 1959 1960 // That includes picking up the appropriate access specifier. 1961 if (AS != AS_none) IndirectField->setAccess(AS); 1962 1963 Chaining.resize(OldChainingSize); 1964 } 1965 } 1966 } 1967 1968 return Invalid; 1969} 1970 1971/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1972/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1973/// illegal input values are mapped to SC_None. 1974static StorageClass 1975StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1976 switch (StorageClassSpec) { 1977 case DeclSpec::SCS_unspecified: return SC_None; 1978 case DeclSpec::SCS_extern: return SC_Extern; 1979 case DeclSpec::SCS_static: return SC_Static; 1980 case DeclSpec::SCS_auto: return SC_Auto; 1981 case DeclSpec::SCS_register: return SC_Register; 1982 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 1983 // Illegal SCSs map to None: error reporting is up to the caller. 1984 case DeclSpec::SCS_mutable: // Fall through. 1985 case DeclSpec::SCS_typedef: return SC_None; 1986 } 1987 llvm_unreachable("unknown storage class specifier"); 1988} 1989 1990/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1991/// a StorageClass. Any error reporting is up to the caller: 1992/// illegal input values are mapped to SC_None. 1993static StorageClass 1994StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1995 switch (StorageClassSpec) { 1996 case DeclSpec::SCS_unspecified: return SC_None; 1997 case DeclSpec::SCS_extern: return SC_Extern; 1998 case DeclSpec::SCS_static: return SC_Static; 1999 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2000 // Illegal SCSs map to None: error reporting is up to the caller. 2001 case DeclSpec::SCS_auto: // Fall through. 2002 case DeclSpec::SCS_mutable: // Fall through. 2003 case DeclSpec::SCS_register: // Fall through. 2004 case DeclSpec::SCS_typedef: return SC_None; 2005 } 2006 llvm_unreachable("unknown storage class specifier"); 2007} 2008 2009/// BuildAnonymousStructOrUnion - Handle the declaration of an 2010/// anonymous structure or union. Anonymous unions are a C++ feature 2011/// (C++ [class.union]) and a GNU C extension; anonymous structures 2012/// are a GNU C and GNU C++ extension. 2013Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2014 AccessSpecifier AS, 2015 RecordDecl *Record) { 2016 DeclContext *Owner = Record->getDeclContext(); 2017 2018 // Diagnose whether this anonymous struct/union is an extension. 2019 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2020 Diag(Record->getLocation(), diag::ext_anonymous_union); 2021 else if (!Record->isUnion()) 2022 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2023 2024 // C and C++ require different kinds of checks for anonymous 2025 // structs/unions. 2026 bool Invalid = false; 2027 if (getLangOptions().CPlusPlus) { 2028 const char* PrevSpec = 0; 2029 unsigned DiagID; 2030 // C++ [class.union]p3: 2031 // Anonymous unions declared in a named namespace or in the 2032 // global namespace shall be declared static. 2033 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2034 (isa<TranslationUnitDecl>(Owner) || 2035 (isa<NamespaceDecl>(Owner) && 2036 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2037 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2038 Invalid = true; 2039 2040 // Recover by adding 'static'. 2041 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2042 PrevSpec, DiagID, getLangOptions()); 2043 } 2044 // C++ [class.union]p3: 2045 // A storage class is not allowed in a declaration of an 2046 // anonymous union in a class scope. 2047 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2048 isa<RecordDecl>(Owner)) { 2049 Diag(DS.getStorageClassSpecLoc(), 2050 diag::err_anonymous_union_with_storage_spec); 2051 Invalid = true; 2052 2053 // Recover by removing the storage specifier. 2054 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2055 PrevSpec, DiagID, getLangOptions()); 2056 } 2057 2058 // C++ [class.union]p2: 2059 // The member-specification of an anonymous union shall only 2060 // define non-static data members. [Note: nested types and 2061 // functions cannot be declared within an anonymous union. ] 2062 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2063 MemEnd = Record->decls_end(); 2064 Mem != MemEnd; ++Mem) { 2065 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2066 // C++ [class.union]p3: 2067 // An anonymous union shall not have private or protected 2068 // members (clause 11). 2069 assert(FD->getAccess() != AS_none); 2070 if (FD->getAccess() != AS_public) { 2071 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2072 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2073 Invalid = true; 2074 } 2075 2076 if (CheckNontrivialField(FD)) 2077 Invalid = true; 2078 } else if ((*Mem)->isImplicit()) { 2079 // Any implicit members are fine. 2080 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2081 // This is a type that showed up in an 2082 // elaborated-type-specifier inside the anonymous struct or 2083 // union, but which actually declares a type outside of the 2084 // anonymous struct or union. It's okay. 2085 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2086 if (!MemRecord->isAnonymousStructOrUnion() && 2087 MemRecord->getDeclName()) { 2088 // Visual C++ allows type definition in anonymous struct or union. 2089 if (getLangOptions().Microsoft) 2090 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2091 << (int)Record->isUnion(); 2092 else { 2093 // This is a nested type declaration. 2094 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2095 << (int)Record->isUnion(); 2096 Invalid = true; 2097 } 2098 } 2099 } else if (isa<AccessSpecDecl>(*Mem)) { 2100 // Any access specifier is fine. 2101 } else { 2102 // We have something that isn't a non-static data 2103 // member. Complain about it. 2104 unsigned DK = diag::err_anonymous_record_bad_member; 2105 if (isa<TypeDecl>(*Mem)) 2106 DK = diag::err_anonymous_record_with_type; 2107 else if (isa<FunctionDecl>(*Mem)) 2108 DK = diag::err_anonymous_record_with_function; 2109 else if (isa<VarDecl>(*Mem)) 2110 DK = diag::err_anonymous_record_with_static; 2111 2112 // Visual C++ allows type definition in anonymous struct or union. 2113 if (getLangOptions().Microsoft && 2114 DK == diag::err_anonymous_record_with_type) 2115 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2116 << (int)Record->isUnion(); 2117 else { 2118 Diag((*Mem)->getLocation(), DK) 2119 << (int)Record->isUnion(); 2120 Invalid = true; 2121 } 2122 } 2123 } 2124 } 2125 2126 if (!Record->isUnion() && !Owner->isRecord()) { 2127 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2128 << (int)getLangOptions().CPlusPlus; 2129 Invalid = true; 2130 } 2131 2132 // Mock up a declarator. 2133 Declarator Dc(DS, Declarator::TypeNameContext); 2134 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2135 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2136 2137 // Create a declaration for this anonymous struct/union. 2138 NamedDecl *Anon = 0; 2139 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2140 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 2141 /*IdentifierInfo=*/0, 2142 Context.getTypeDeclType(Record), 2143 TInfo, 2144 /*BitWidth=*/0, /*Mutable=*/false); 2145 Anon->setAccess(AS); 2146 if (getLangOptions().CPlusPlus) 2147 FieldCollector->Add(cast<FieldDecl>(Anon)); 2148 } else { 2149 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2150 assert(SCSpec != DeclSpec::SCS_typedef && 2151 "Parser allowed 'typedef' as storage class VarDecl."); 2152 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2153 if (SCSpec == DeclSpec::SCS_mutable) { 2154 // mutable can only appear on non-static class members, so it's always 2155 // an error here 2156 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2157 Invalid = true; 2158 SC = SC_None; 2159 } 2160 SCSpec = DS.getStorageClassSpecAsWritten(); 2161 VarDecl::StorageClass SCAsWritten 2162 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2163 2164 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 2165 /*IdentifierInfo=*/0, 2166 Context.getTypeDeclType(Record), 2167 TInfo, SC, SCAsWritten); 2168 } 2169 Anon->setImplicit(); 2170 2171 // Add the anonymous struct/union object to the current 2172 // context. We'll be referencing this object when we refer to one of 2173 // its members. 2174 Owner->addDecl(Anon); 2175 2176 // Inject the members of the anonymous struct/union into the owning 2177 // context and into the identifier resolver chain for name lookup 2178 // purposes. 2179 llvm::SmallVector<NamedDecl*, 2> Chain; 2180 Chain.push_back(Anon); 2181 2182 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2183 Chain, false)) 2184 Invalid = true; 2185 2186 // Mark this as an anonymous struct/union type. Note that we do not 2187 // do this until after we have already checked and injected the 2188 // members of this anonymous struct/union type, because otherwise 2189 // the members could be injected twice: once by DeclContext when it 2190 // builds its lookup table, and once by 2191 // InjectAnonymousStructOrUnionMembers. 2192 Record->setAnonymousStructOrUnion(true); 2193 2194 if (Invalid) 2195 Anon->setInvalidDecl(); 2196 2197 return Anon; 2198} 2199 2200/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2201/// Microsoft C anonymous structure. 2202/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2203/// Example: 2204/// 2205/// struct A { int a; }; 2206/// struct B { struct A; int b; }; 2207/// 2208/// void foo() { 2209/// B var; 2210/// var.a = 3; 2211/// } 2212/// 2213Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2214 RecordDecl *Record) { 2215 2216 // If there is no Record, get the record via the typedef. 2217 if (!Record) 2218 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2219 2220 // Mock up a declarator. 2221 Declarator Dc(DS, Declarator::TypeNameContext); 2222 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2223 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2224 2225 // Create a declaration for this anonymous struct. 2226 NamedDecl* Anon = FieldDecl::Create(Context, 2227 cast<RecordDecl>(CurContext), 2228 DS.getSourceRange().getBegin(), 2229 /*IdentifierInfo=*/0, 2230 Context.getTypeDeclType(Record), 2231 TInfo, 2232 /*BitWidth=*/0, /*Mutable=*/false); 2233 Anon->setImplicit(); 2234 2235 // Add the anonymous struct object to the current context. 2236 CurContext->addDecl(Anon); 2237 2238 // Inject the members of the anonymous struct into the current 2239 // context and into the identifier resolver chain for name lookup 2240 // purposes. 2241 llvm::SmallVector<NamedDecl*, 2> Chain; 2242 Chain.push_back(Anon); 2243 2244 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2245 Record->getDefinition(), 2246 AS_none, Chain, true)) 2247 Anon->setInvalidDecl(); 2248 2249 return Anon; 2250} 2251 2252/// GetNameForDeclarator - Determine the full declaration name for the 2253/// given Declarator. 2254DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2255 return GetNameFromUnqualifiedId(D.getName()); 2256} 2257 2258/// \brief Retrieves the declaration name from a parsed unqualified-id. 2259DeclarationNameInfo 2260Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2261 DeclarationNameInfo NameInfo; 2262 NameInfo.setLoc(Name.StartLocation); 2263 2264 switch (Name.getKind()) { 2265 2266 case UnqualifiedId::IK_Identifier: 2267 NameInfo.setName(Name.Identifier); 2268 NameInfo.setLoc(Name.StartLocation); 2269 return NameInfo; 2270 2271 case UnqualifiedId::IK_OperatorFunctionId: 2272 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2273 Name.OperatorFunctionId.Operator)); 2274 NameInfo.setLoc(Name.StartLocation); 2275 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2276 = Name.OperatorFunctionId.SymbolLocations[0]; 2277 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2278 = Name.EndLocation.getRawEncoding(); 2279 return NameInfo; 2280 2281 case UnqualifiedId::IK_LiteralOperatorId: 2282 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2283 Name.Identifier)); 2284 NameInfo.setLoc(Name.StartLocation); 2285 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2286 return NameInfo; 2287 2288 case UnqualifiedId::IK_ConversionFunctionId: { 2289 TypeSourceInfo *TInfo; 2290 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2291 if (Ty.isNull()) 2292 return DeclarationNameInfo(); 2293 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2294 Context.getCanonicalType(Ty))); 2295 NameInfo.setLoc(Name.StartLocation); 2296 NameInfo.setNamedTypeInfo(TInfo); 2297 return NameInfo; 2298 } 2299 2300 case UnqualifiedId::IK_ConstructorName: { 2301 TypeSourceInfo *TInfo; 2302 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2303 if (Ty.isNull()) 2304 return DeclarationNameInfo(); 2305 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2306 Context.getCanonicalType(Ty))); 2307 NameInfo.setLoc(Name.StartLocation); 2308 NameInfo.setNamedTypeInfo(TInfo); 2309 return NameInfo; 2310 } 2311 2312 case UnqualifiedId::IK_ConstructorTemplateId: { 2313 // In well-formed code, we can only have a constructor 2314 // template-id that refers to the current context, so go there 2315 // to find the actual type being constructed. 2316 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2317 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2318 return DeclarationNameInfo(); 2319 2320 // Determine the type of the class being constructed. 2321 QualType CurClassType = Context.getTypeDeclType(CurClass); 2322 2323 // FIXME: Check two things: that the template-id names the same type as 2324 // CurClassType, and that the template-id does not occur when the name 2325 // was qualified. 2326 2327 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2328 Context.getCanonicalType(CurClassType))); 2329 NameInfo.setLoc(Name.StartLocation); 2330 // FIXME: should we retrieve TypeSourceInfo? 2331 NameInfo.setNamedTypeInfo(0); 2332 return NameInfo; 2333 } 2334 2335 case UnqualifiedId::IK_DestructorName: { 2336 TypeSourceInfo *TInfo; 2337 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2338 if (Ty.isNull()) 2339 return DeclarationNameInfo(); 2340 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2341 Context.getCanonicalType(Ty))); 2342 NameInfo.setLoc(Name.StartLocation); 2343 NameInfo.setNamedTypeInfo(TInfo); 2344 return NameInfo; 2345 } 2346 2347 case UnqualifiedId::IK_TemplateId: { 2348 TemplateName TName = Name.TemplateId->Template.get(); 2349 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2350 return Context.getNameForTemplate(TName, TNameLoc); 2351 } 2352 2353 } // switch (Name.getKind()) 2354 2355 assert(false && "Unknown name kind"); 2356 return DeclarationNameInfo(); 2357} 2358 2359/// isNearlyMatchingFunction - Determine whether the C++ functions 2360/// Declaration and Definition are "nearly" matching. This heuristic 2361/// is used to improve diagnostics in the case where an out-of-line 2362/// function definition doesn't match any declaration within 2363/// the class or namespace. 2364static bool isNearlyMatchingFunction(ASTContext &Context, 2365 FunctionDecl *Declaration, 2366 FunctionDecl *Definition) { 2367 if (Declaration->param_size() != Definition->param_size()) 2368 return false; 2369 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2370 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2371 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2372 2373 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2374 DefParamTy.getNonReferenceType())) 2375 return false; 2376 } 2377 2378 return true; 2379} 2380 2381/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2382/// declarator needs to be rebuilt in the current instantiation. 2383/// Any bits of declarator which appear before the name are valid for 2384/// consideration here. That's specifically the type in the decl spec 2385/// and the base type in any member-pointer chunks. 2386static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2387 DeclarationName Name) { 2388 // The types we specifically need to rebuild are: 2389 // - typenames, typeofs, and decltypes 2390 // - types which will become injected class names 2391 // Of course, we also need to rebuild any type referencing such a 2392 // type. It's safest to just say "dependent", but we call out a 2393 // few cases here. 2394 2395 DeclSpec &DS = D.getMutableDeclSpec(); 2396 switch (DS.getTypeSpecType()) { 2397 case DeclSpec::TST_typename: 2398 case DeclSpec::TST_typeofType: 2399 case DeclSpec::TST_decltype: { 2400 // Grab the type from the parser. 2401 TypeSourceInfo *TSI = 0; 2402 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2403 if (T.isNull() || !T->isDependentType()) break; 2404 2405 // Make sure there's a type source info. This isn't really much 2406 // of a waste; most dependent types should have type source info 2407 // attached already. 2408 if (!TSI) 2409 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2410 2411 // Rebuild the type in the current instantiation. 2412 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2413 if (!TSI) return true; 2414 2415 // Store the new type back in the decl spec. 2416 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2417 DS.UpdateTypeRep(LocType); 2418 break; 2419 } 2420 2421 case DeclSpec::TST_typeofExpr: { 2422 Expr *E = DS.getRepAsExpr(); 2423 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2424 if (Result.isInvalid()) return true; 2425 DS.UpdateExprRep(Result.get()); 2426 break; 2427 } 2428 2429 default: 2430 // Nothing to do for these decl specs. 2431 break; 2432 } 2433 2434 // It doesn't matter what order we do this in. 2435 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2436 DeclaratorChunk &Chunk = D.getTypeObject(I); 2437 2438 // The only type information in the declarator which can come 2439 // before the declaration name is the base type of a member 2440 // pointer. 2441 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2442 continue; 2443 2444 // Rebuild the scope specifier in-place. 2445 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2446 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2447 return true; 2448 } 2449 2450 return false; 2451} 2452 2453Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2454 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2455} 2456 2457Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2458 MultiTemplateParamsArg TemplateParamLists, 2459 bool IsFunctionDefinition) { 2460 // TODO: consider using NameInfo for diagnostic. 2461 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2462 DeclarationName Name = NameInfo.getName(); 2463 2464 // All of these full declarators require an identifier. If it doesn't have 2465 // one, the ParsedFreeStandingDeclSpec action should be used. 2466 if (!Name) { 2467 if (!D.isInvalidType()) // Reject this if we think it is valid. 2468 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2469 diag::err_declarator_need_ident) 2470 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2471 return 0; 2472 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2473 return 0; 2474 2475 // The scope passed in may not be a decl scope. Zip up the scope tree until 2476 // we find one that is. 2477 while ((S->getFlags() & Scope::DeclScope) == 0 || 2478 (S->getFlags() & Scope::TemplateParamScope) != 0) 2479 S = S->getParent(); 2480 2481 DeclContext *DC = CurContext; 2482 if (D.getCXXScopeSpec().isInvalid()) 2483 D.setInvalidType(); 2484 else if (D.getCXXScopeSpec().isSet()) { 2485 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2486 UPPC_DeclarationQualifier)) 2487 return 0; 2488 2489 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2490 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2491 if (!DC) { 2492 // If we could not compute the declaration context, it's because the 2493 // declaration context is dependent but does not refer to a class, 2494 // class template, or class template partial specialization. Complain 2495 // and return early, to avoid the coming semantic disaster. 2496 Diag(D.getIdentifierLoc(), 2497 diag::err_template_qualified_declarator_no_match) 2498 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2499 << D.getCXXScopeSpec().getRange(); 2500 return 0; 2501 } 2502 2503 bool IsDependentContext = DC->isDependentContext(); 2504 2505 if (!IsDependentContext && 2506 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2507 return 0; 2508 2509 if (isa<CXXRecordDecl>(DC)) { 2510 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2511 Diag(D.getIdentifierLoc(), 2512 diag::err_member_def_undefined_record) 2513 << Name << DC << D.getCXXScopeSpec().getRange(); 2514 D.setInvalidType(); 2515 } else if (isa<CXXRecordDecl>(CurContext) && 2516 !D.getDeclSpec().isFriendSpecified()) { 2517 // The user provided a superfluous scope specifier inside a class 2518 // definition: 2519 // 2520 // class X { 2521 // void X::f(); 2522 // }; 2523 if (CurContext->Equals(DC)) 2524 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2525 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2526 else 2527 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2528 << Name << D.getCXXScopeSpec().getRange(); 2529 2530 // Pretend that this qualifier was not here. 2531 D.getCXXScopeSpec().clear(); 2532 } 2533 } 2534 2535 // Check whether we need to rebuild the type of the given 2536 // declaration in the current instantiation. 2537 if (EnteringContext && IsDependentContext && 2538 TemplateParamLists.size() != 0) { 2539 ContextRAII SavedContext(*this, DC); 2540 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2541 D.setInvalidType(); 2542 } 2543 } 2544 2545 // C++ [class.mem]p13: 2546 // If T is the name of a class, then each of the following shall have a 2547 // name different from T: 2548 // - every static data member of class T; 2549 // - every member function of class T 2550 // - every member of class T that is itself a type; 2551 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2552 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2553 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2554 << Name; 2555 2556 // If this is a typedef, we'll end up spewing multiple diagnostics. 2557 // Just return early; it's safer. 2558 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2559 return 0; 2560 } 2561 2562 NamedDecl *New; 2563 2564 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2565 QualType R = TInfo->getType(); 2566 2567 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 2568 UPPC_DeclarationType)) 2569 D.setInvalidType(); 2570 2571 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2572 ForRedeclaration); 2573 2574 // See if this is a redefinition of a variable in the same scope. 2575 if (!D.getCXXScopeSpec().isSet()) { 2576 bool IsLinkageLookup = false; 2577 2578 // If the declaration we're planning to build will be a function 2579 // or object with linkage, then look for another declaration with 2580 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2581 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2582 /* Do nothing*/; 2583 else if (R->isFunctionType()) { 2584 if (CurContext->isFunctionOrMethod() || 2585 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2586 IsLinkageLookup = true; 2587 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2588 IsLinkageLookup = true; 2589 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2590 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2591 IsLinkageLookup = true; 2592 2593 if (IsLinkageLookup) 2594 Previous.clear(LookupRedeclarationWithLinkage); 2595 2596 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2597 } else { // Something like "int foo::x;" 2598 LookupQualifiedName(Previous, DC); 2599 2600 // Don't consider using declarations as previous declarations for 2601 // out-of-line members. 2602 RemoveUsingDecls(Previous); 2603 2604 // C++ 7.3.1.2p2: 2605 // Members (including explicit specializations of templates) of a named 2606 // namespace can also be defined outside that namespace by explicit 2607 // qualification of the name being defined, provided that the entity being 2608 // defined was already declared in the namespace and the definition appears 2609 // after the point of declaration in a namespace that encloses the 2610 // declarations namespace. 2611 // 2612 // Note that we only check the context at this point. We don't yet 2613 // have enough information to make sure that PrevDecl is actually 2614 // the declaration we want to match. For example, given: 2615 // 2616 // class X { 2617 // void f(); 2618 // void f(float); 2619 // }; 2620 // 2621 // void X::f(int) { } // ill-formed 2622 // 2623 // In this case, PrevDecl will point to the overload set 2624 // containing the two f's declared in X, but neither of them 2625 // matches. 2626 2627 // First check whether we named the global scope. 2628 if (isa<TranslationUnitDecl>(DC)) { 2629 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2630 << Name << D.getCXXScopeSpec().getRange(); 2631 } else { 2632 DeclContext *Cur = CurContext; 2633 while (isa<LinkageSpecDecl>(Cur)) 2634 Cur = Cur->getParent(); 2635 if (!Cur->Encloses(DC)) { 2636 // The qualifying scope doesn't enclose the original declaration. 2637 // Emit diagnostic based on current scope. 2638 SourceLocation L = D.getIdentifierLoc(); 2639 SourceRange R = D.getCXXScopeSpec().getRange(); 2640 if (isa<FunctionDecl>(Cur)) 2641 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2642 else 2643 Diag(L, diag::err_invalid_declarator_scope) 2644 << Name << cast<NamedDecl>(DC) << R; 2645 D.setInvalidType(); 2646 } 2647 } 2648 } 2649 2650 if (Previous.isSingleResult() && 2651 Previous.getFoundDecl()->isTemplateParameter()) { 2652 // Maybe we will complain about the shadowed template parameter. 2653 if (!D.isInvalidType()) 2654 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2655 Previous.getFoundDecl())) 2656 D.setInvalidType(); 2657 2658 // Just pretend that we didn't see the previous declaration. 2659 Previous.clear(); 2660 } 2661 2662 // In C++, the previous declaration we find might be a tag type 2663 // (class or enum). In this case, the new declaration will hide the 2664 // tag type. Note that this does does not apply if we're declaring a 2665 // typedef (C++ [dcl.typedef]p4). 2666 if (Previous.isSingleTagDecl() && 2667 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2668 Previous.clear(); 2669 2670 bool Redeclaration = false; 2671 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2672 if (TemplateParamLists.size()) { 2673 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2674 return 0; 2675 } 2676 2677 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2678 } else if (R->isFunctionType()) { 2679 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2680 move(TemplateParamLists), 2681 IsFunctionDefinition, Redeclaration); 2682 } else { 2683 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2684 move(TemplateParamLists), 2685 Redeclaration); 2686 } 2687 2688 if (New == 0) 2689 return 0; 2690 2691 // If this has an identifier and is not an invalid redeclaration or 2692 // function template specialization, add it to the scope stack. 2693 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2694 PushOnScopeChains(New, S); 2695 2696 return New; 2697} 2698 2699/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2700/// types into constant array types in certain situations which would otherwise 2701/// be errors (for GCC compatibility). 2702static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2703 ASTContext &Context, 2704 bool &SizeIsNegative, 2705 llvm::APSInt &Oversized) { 2706 // This method tries to turn a variable array into a constant 2707 // array even when the size isn't an ICE. This is necessary 2708 // for compatibility with code that depends on gcc's buggy 2709 // constant expression folding, like struct {char x[(int)(char*)2];} 2710 SizeIsNegative = false; 2711 Oversized = 0; 2712 2713 if (T->isDependentType()) 2714 return QualType(); 2715 2716 QualifierCollector Qs; 2717 const Type *Ty = Qs.strip(T); 2718 2719 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2720 QualType Pointee = PTy->getPointeeType(); 2721 QualType FixedType = 2722 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2723 Oversized); 2724 if (FixedType.isNull()) return FixedType; 2725 FixedType = Context.getPointerType(FixedType); 2726 return Qs.apply(Context, FixedType); 2727 } 2728 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 2729 QualType Inner = PTy->getInnerType(); 2730 QualType FixedType = 2731 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 2732 Oversized); 2733 if (FixedType.isNull()) return FixedType; 2734 FixedType = Context.getParenType(FixedType); 2735 return Qs.apply(Context, FixedType); 2736 } 2737 2738 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2739 if (!VLATy) 2740 return QualType(); 2741 // FIXME: We should probably handle this case 2742 if (VLATy->getElementType()->isVariablyModifiedType()) 2743 return QualType(); 2744 2745 Expr::EvalResult EvalResult; 2746 if (!VLATy->getSizeExpr() || 2747 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2748 !EvalResult.Val.isInt()) 2749 return QualType(); 2750 2751 // Check whether the array size is negative. 2752 llvm::APSInt &Res = EvalResult.Val.getInt(); 2753 if (Res.isSigned() && Res.isNegative()) { 2754 SizeIsNegative = true; 2755 return QualType(); 2756 } 2757 2758 // Check whether the array is too large to be addressed. 2759 unsigned ActiveSizeBits 2760 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2761 Res); 2762 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2763 Oversized = Res; 2764 return QualType(); 2765 } 2766 2767 return Context.getConstantArrayType(VLATy->getElementType(), 2768 Res, ArrayType::Normal, 0); 2769} 2770 2771/// \brief Register the given locally-scoped external C declaration so 2772/// that it can be found later for redeclarations 2773void 2774Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2775 const LookupResult &Previous, 2776 Scope *S) { 2777 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2778 "Decl is not a locally-scoped decl!"); 2779 // Note that we have a locally-scoped external with this name. 2780 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2781 2782 if (!Previous.isSingleResult()) 2783 return; 2784 2785 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2786 2787 // If there was a previous declaration of this variable, it may be 2788 // in our identifier chain. Update the identifier chain with the new 2789 // declaration. 2790 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2791 // The previous declaration was found on the identifer resolver 2792 // chain, so remove it from its scope. 2793 while (S && !S->isDeclScope(PrevDecl)) 2794 S = S->getParent(); 2795 2796 if (S) 2797 S->RemoveDecl(PrevDecl); 2798 } 2799} 2800 2801/// \brief Diagnose function specifiers on a declaration of an identifier that 2802/// does not identify a function. 2803void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2804 // FIXME: We should probably indicate the identifier in question to avoid 2805 // confusion for constructs like "inline int a(), b;" 2806 if (D.getDeclSpec().isInlineSpecified()) 2807 Diag(D.getDeclSpec().getInlineSpecLoc(), 2808 diag::err_inline_non_function); 2809 2810 if (D.getDeclSpec().isVirtualSpecified()) 2811 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2812 diag::err_virtual_non_function); 2813 2814 if (D.getDeclSpec().isExplicitSpecified()) 2815 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2816 diag::err_explicit_non_function); 2817} 2818 2819NamedDecl* 2820Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2821 QualType R, TypeSourceInfo *TInfo, 2822 LookupResult &Previous, bool &Redeclaration) { 2823 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2824 if (D.getCXXScopeSpec().isSet()) { 2825 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2826 << D.getCXXScopeSpec().getRange(); 2827 D.setInvalidType(); 2828 // Pretend we didn't see the scope specifier. 2829 DC = CurContext; 2830 Previous.clear(); 2831 } 2832 2833 if (getLangOptions().CPlusPlus) { 2834 // Check that there are no default arguments (C++ only). 2835 CheckExtraCXXDefaultArguments(D); 2836 } 2837 2838 DiagnoseFunctionSpecifiers(D); 2839 2840 if (D.getDeclSpec().isThreadSpecified()) 2841 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2842 2843 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2844 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2845 << D.getName().getSourceRange(); 2846 return 0; 2847 } 2848 2849 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2850 if (!NewTD) return 0; 2851 2852 // Handle attributes prior to checking for duplicates in MergeVarDecl 2853 ProcessDeclAttributes(S, NewTD, D); 2854 2855 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2856 // then it shall have block scope. 2857 // Note that variably modified types must be fixed before merging the decl so 2858 // that redeclarations will match. 2859 QualType T = NewTD->getUnderlyingType(); 2860 if (T->isVariablyModifiedType()) { 2861 getCurFunction()->setHasBranchProtectedScope(); 2862 2863 if (S->getFnParent() == 0) { 2864 bool SizeIsNegative; 2865 llvm::APSInt Oversized; 2866 QualType FixedTy = 2867 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2868 Oversized); 2869 if (!FixedTy.isNull()) { 2870 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2871 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2872 } else { 2873 if (SizeIsNegative) 2874 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2875 else if (T->isVariableArrayType()) 2876 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2877 else if (Oversized.getBoolValue()) 2878 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2879 << Oversized.toString(10); 2880 else 2881 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2882 NewTD->setInvalidDecl(); 2883 } 2884 } 2885 } 2886 2887 // Merge the decl with the existing one if appropriate. If the decl is 2888 // in an outer scope, it isn't the same thing. 2889 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2890 if (!Previous.empty()) { 2891 Redeclaration = true; 2892 MergeTypeDefDecl(NewTD, Previous); 2893 } 2894 2895 // If this is the C FILE type, notify the AST context. 2896 if (IdentifierInfo *II = NewTD->getIdentifier()) 2897 if (!NewTD->isInvalidDecl() && 2898 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2899 if (II->isStr("FILE")) 2900 Context.setFILEDecl(NewTD); 2901 else if (II->isStr("jmp_buf")) 2902 Context.setjmp_bufDecl(NewTD); 2903 else if (II->isStr("sigjmp_buf")) 2904 Context.setsigjmp_bufDecl(NewTD); 2905 else if (II->isStr("__builtin_va_list")) 2906 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 2907 } 2908 2909 return NewTD; 2910} 2911 2912/// \brief Determines whether the given declaration is an out-of-scope 2913/// previous declaration. 2914/// 2915/// This routine should be invoked when name lookup has found a 2916/// previous declaration (PrevDecl) that is not in the scope where a 2917/// new declaration by the same name is being introduced. If the new 2918/// declaration occurs in a local scope, previous declarations with 2919/// linkage may still be considered previous declarations (C99 2920/// 6.2.2p4-5, C++ [basic.link]p6). 2921/// 2922/// \param PrevDecl the previous declaration found by name 2923/// lookup 2924/// 2925/// \param DC the context in which the new declaration is being 2926/// declared. 2927/// 2928/// \returns true if PrevDecl is an out-of-scope previous declaration 2929/// for a new delcaration with the same name. 2930static bool 2931isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2932 ASTContext &Context) { 2933 if (!PrevDecl) 2934 return false; 2935 2936 if (!PrevDecl->hasLinkage()) 2937 return false; 2938 2939 if (Context.getLangOptions().CPlusPlus) { 2940 // C++ [basic.link]p6: 2941 // If there is a visible declaration of an entity with linkage 2942 // having the same name and type, ignoring entities declared 2943 // outside the innermost enclosing namespace scope, the block 2944 // scope declaration declares that same entity and receives the 2945 // linkage of the previous declaration. 2946 DeclContext *OuterContext = DC->getRedeclContext(); 2947 if (!OuterContext->isFunctionOrMethod()) 2948 // This rule only applies to block-scope declarations. 2949 return false; 2950 2951 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2952 if (PrevOuterContext->isRecord()) 2953 // We found a member function: ignore it. 2954 return false; 2955 2956 // Find the innermost enclosing namespace for the new and 2957 // previous declarations. 2958 OuterContext = OuterContext->getEnclosingNamespaceContext(); 2959 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 2960 2961 // The previous declaration is in a different namespace, so it 2962 // isn't the same function. 2963 if (!OuterContext->Equals(PrevOuterContext)) 2964 return false; 2965 } 2966 2967 return true; 2968} 2969 2970static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2971 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2972 if (!SS.isSet()) return; 2973 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 2974} 2975 2976NamedDecl* 2977Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 2978 QualType R, TypeSourceInfo *TInfo, 2979 LookupResult &Previous, 2980 MultiTemplateParamsArg TemplateParamLists, 2981 bool &Redeclaration) { 2982 DeclarationName Name = GetNameForDeclarator(D).getName(); 2983 2984 // Check that there are no default arguments (C++ only). 2985 if (getLangOptions().CPlusPlus) 2986 CheckExtraCXXDefaultArguments(D); 2987 2988 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2989 assert(SCSpec != DeclSpec::SCS_typedef && 2990 "Parser allowed 'typedef' as storage class VarDecl."); 2991 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2992 if (SCSpec == DeclSpec::SCS_mutable) { 2993 // mutable can only appear on non-static class members, so it's always 2994 // an error here 2995 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2996 D.setInvalidType(); 2997 SC = SC_None; 2998 } 2999 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3000 VarDecl::StorageClass SCAsWritten 3001 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3002 3003 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3004 if (!II) { 3005 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3006 << Name.getAsString(); 3007 return 0; 3008 } 3009 3010 DiagnoseFunctionSpecifiers(D); 3011 3012 if (!DC->isRecord() && S->getFnParent() == 0) { 3013 // C99 6.9p2: The storage-class specifiers auto and register shall not 3014 // appear in the declaration specifiers in an external declaration. 3015 if (SC == SC_Auto || SC == SC_Register) { 3016 3017 // If this is a register variable with an asm label specified, then this 3018 // is a GNU extension. 3019 if (SC == SC_Register && D.getAsmLabel()) 3020 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3021 else 3022 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3023 D.setInvalidType(); 3024 } 3025 } 3026 3027 bool isExplicitSpecialization = false; 3028 VarDecl *NewVD; 3029 if (!getLangOptions().CPlusPlus) { 3030 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 3031 II, R, TInfo, SC, SCAsWritten); 3032 3033 if (D.isInvalidType()) 3034 NewVD->setInvalidDecl(); 3035 } else { 3036 if (DC->isRecord() && !CurContext->isRecord()) { 3037 // This is an out-of-line definition of a static data member. 3038 if (SC == SC_Static) { 3039 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3040 diag::err_static_out_of_line) 3041 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3042 } else if (SC == SC_None) 3043 SC = SC_Static; 3044 } 3045 if (SC == SC_Static) { 3046 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3047 if (RD->isLocalClass()) 3048 Diag(D.getIdentifierLoc(), 3049 diag::err_static_data_member_not_allowed_in_local_class) 3050 << Name << RD->getDeclName(); 3051 3052 // C++ [class.union]p1: If a union contains a static data member, 3053 // the program is ill-formed. 3054 // 3055 // We also disallow static data members in anonymous structs. 3056 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3057 Diag(D.getIdentifierLoc(), 3058 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3059 << Name << RD->isUnion(); 3060 } 3061 } 3062 3063 // Match up the template parameter lists with the scope specifier, then 3064 // determine whether we have a template or a template specialization. 3065 isExplicitSpecialization = false; 3066 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3067 bool Invalid = false; 3068 if (TemplateParameterList *TemplateParams 3069 = MatchTemplateParametersToScopeSpecifier( 3070 D.getDeclSpec().getSourceRange().getBegin(), 3071 D.getCXXScopeSpec(), 3072 TemplateParamLists.get(), 3073 TemplateParamLists.size(), 3074 /*never a friend*/ false, 3075 isExplicitSpecialization, 3076 Invalid)) { 3077 // All but one template parameter lists have been matching. 3078 --NumMatchedTemplateParamLists; 3079 3080 if (TemplateParams->size() > 0) { 3081 // There is no such thing as a variable template. 3082 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3083 << II 3084 << SourceRange(TemplateParams->getTemplateLoc(), 3085 TemplateParams->getRAngleLoc()); 3086 return 0; 3087 } else { 3088 // There is an extraneous 'template<>' for this variable. Complain 3089 // about it, but allow the declaration of the variable. 3090 Diag(TemplateParams->getTemplateLoc(), 3091 diag::err_template_variable_noparams) 3092 << II 3093 << SourceRange(TemplateParams->getTemplateLoc(), 3094 TemplateParams->getRAngleLoc()); 3095 3096 isExplicitSpecialization = true; 3097 } 3098 } 3099 3100 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 3101 II, R, TInfo, SC, SCAsWritten); 3102 3103 // If this decl has an auto type in need of deduction, make a note of the 3104 // Decl so we can diagnose uses of it in its own initializer. 3105 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3106 R->getContainedAutoType()) 3107 ParsingInitForAutoVars.insert(NewVD); 3108 3109 if (D.isInvalidType() || Invalid) 3110 NewVD->setInvalidDecl(); 3111 3112 SetNestedNameSpecifier(NewVD, D); 3113 3114 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3115 NewVD->setTemplateParameterListsInfo(Context, 3116 NumMatchedTemplateParamLists, 3117 TemplateParamLists.release()); 3118 } 3119 } 3120 3121 if (D.getDeclSpec().isThreadSpecified()) { 3122 if (NewVD->hasLocalStorage()) 3123 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3124 else if (!Context.Target.isTLSSupported()) 3125 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3126 else 3127 NewVD->setThreadSpecified(true); 3128 } 3129 3130 // Set the lexical context. If the declarator has a C++ scope specifier, the 3131 // lexical context will be different from the semantic context. 3132 NewVD->setLexicalDeclContext(CurContext); 3133 3134 // Handle attributes prior to checking for duplicates in MergeVarDecl 3135 ProcessDeclAttributes(S, NewVD, D); 3136 3137 // Handle GNU asm-label extension (encoded as an attribute). 3138 if (Expr *E = (Expr*)D.getAsmLabel()) { 3139 // The parser guarantees this is a string. 3140 StringLiteral *SE = cast<StringLiteral>(E); 3141 llvm::StringRef Label = SE->getString(); 3142 if (S->getFnParent() != 0) { 3143 switch (SC) { 3144 case SC_None: 3145 case SC_Auto: 3146 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3147 break; 3148 case SC_Register: 3149 if (!Context.Target.isValidGCCRegisterName(Label)) 3150 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3151 break; 3152 case SC_Static: 3153 case SC_Extern: 3154 case SC_PrivateExtern: 3155 break; 3156 } 3157 } 3158 3159 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3160 Context, Label)); 3161 } 3162 3163 // Diagnose shadowed variables before filtering for scope. 3164 if (!D.getCXXScopeSpec().isSet()) 3165 CheckShadow(S, NewVD, Previous); 3166 3167 // Don't consider existing declarations that are in a different 3168 // scope and are out-of-semantic-context declarations (if the new 3169 // declaration has linkage). 3170 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 3171 3172 if (!getLangOptions().CPlusPlus) 3173 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3174 else { 3175 // Merge the decl with the existing one if appropriate. 3176 if (!Previous.empty()) { 3177 if (Previous.isSingleResult() && 3178 isa<FieldDecl>(Previous.getFoundDecl()) && 3179 D.getCXXScopeSpec().isSet()) { 3180 // The user tried to define a non-static data member 3181 // out-of-line (C++ [dcl.meaning]p1). 3182 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3183 << D.getCXXScopeSpec().getRange(); 3184 Previous.clear(); 3185 NewVD->setInvalidDecl(); 3186 } 3187 } else if (D.getCXXScopeSpec().isSet()) { 3188 // No previous declaration in the qualifying scope. 3189 Diag(D.getIdentifierLoc(), diag::err_no_member) 3190 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3191 << D.getCXXScopeSpec().getRange(); 3192 NewVD->setInvalidDecl(); 3193 } 3194 3195 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3196 3197 // This is an explicit specialization of a static data member. Check it. 3198 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3199 CheckMemberSpecialization(NewVD, Previous)) 3200 NewVD->setInvalidDecl(); 3201 } 3202 3203 // attributes declared post-definition are currently ignored 3204 // FIXME: This should be handled in attribute merging, not 3205 // here. 3206 if (Previous.isSingleResult()) { 3207 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3208 if (Def && (Def = Def->getDefinition()) && 3209 Def != NewVD && D.hasAttributes()) { 3210 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3211 Diag(Def->getLocation(), diag::note_previous_definition); 3212 } 3213 } 3214 3215 // If this is a locally-scoped extern C variable, update the map of 3216 // such variables. 3217 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3218 !NewVD->isInvalidDecl()) 3219 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3220 3221 // If there's a #pragma GCC visibility in scope, and this isn't a class 3222 // member, set the visibility of this variable. 3223 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3224 AddPushedVisibilityAttribute(NewVD); 3225 3226 MarkUnusedFileScopedDecl(NewVD); 3227 3228 return NewVD; 3229} 3230 3231/// \brief Diagnose variable or built-in function shadowing. Implements 3232/// -Wshadow. 3233/// 3234/// This method is called whenever a VarDecl is added to a "useful" 3235/// scope. 3236/// 3237/// \param S the scope in which the shadowing name is being declared 3238/// \param R the lookup of the name 3239/// 3240void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3241 // Return if warning is ignored. 3242 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3243 Diagnostic::Ignored) 3244 return; 3245 3246 // Don't diagnose declarations at file scope. 3247 DeclContext *NewDC = D->getDeclContext(); 3248 if (NewDC->isFileContext()) 3249 return; 3250 3251 // Only diagnose if we're shadowing an unambiguous field or variable. 3252 if (R.getResultKind() != LookupResult::Found) 3253 return; 3254 3255 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3256 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3257 return; 3258 3259 // Fields are not shadowed by variables in C++ static methods. 3260 if (isa<FieldDecl>(ShadowedDecl)) 3261 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3262 if (MD->isStatic()) 3263 return; 3264 3265 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3266 if (shadowedVar->isExternC()) { 3267 // Don't warn for this case: 3268 // 3269 // @code 3270 // extern int bob; 3271 // void f() { 3272 // extern int bob; 3273 // } 3274 // @endcode 3275 if (D->isExternC()) 3276 return; 3277 3278 // For shadowing external vars, make sure that we point to the global 3279 // declaration, not a locally scoped extern declaration. 3280 for (VarDecl::redecl_iterator 3281 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3282 I != E; ++I) 3283 if (I->isFileVarDecl()) { 3284 ShadowedDecl = *I; 3285 break; 3286 } 3287 } 3288 3289 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3290 3291 // Only warn about certain kinds of shadowing for class members. 3292 if (NewDC && NewDC->isRecord()) { 3293 // In particular, don't warn about shadowing non-class members. 3294 if (!OldDC->isRecord()) 3295 return; 3296 3297 // TODO: should we warn about static data members shadowing 3298 // static data members from base classes? 3299 3300 // TODO: don't diagnose for inaccessible shadowed members. 3301 // This is hard to do perfectly because we might friend the 3302 // shadowing context, but that's just a false negative. 3303 } 3304 3305 // Determine what kind of declaration we're shadowing. 3306 unsigned Kind; 3307 if (isa<RecordDecl>(OldDC)) { 3308 if (isa<FieldDecl>(ShadowedDecl)) 3309 Kind = 3; // field 3310 else 3311 Kind = 2; // static data member 3312 } else if (OldDC->isFileContext()) 3313 Kind = 1; // global 3314 else 3315 Kind = 0; // local 3316 3317 DeclarationName Name = R.getLookupName(); 3318 3319 // Emit warning and note. 3320 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3321 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3322} 3323 3324/// \brief Check -Wshadow without the advantage of a previous lookup. 3325void Sema::CheckShadow(Scope *S, VarDecl *D) { 3326 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3327 Diagnostic::Ignored) 3328 return; 3329 3330 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3331 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3332 LookupName(R, S); 3333 CheckShadow(S, D, R); 3334} 3335 3336/// \brief Perform semantic checking on a newly-created variable 3337/// declaration. 3338/// 3339/// This routine performs all of the type-checking required for a 3340/// variable declaration once it has been built. It is used both to 3341/// check variables after they have been parsed and their declarators 3342/// have been translated into a declaration, and to check variables 3343/// that have been instantiated from a template. 3344/// 3345/// Sets NewVD->isInvalidDecl() if an error was encountered. 3346void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3347 LookupResult &Previous, 3348 bool &Redeclaration) { 3349 // If the decl is already known invalid, don't check it. 3350 if (NewVD->isInvalidDecl()) 3351 return; 3352 3353 QualType T = NewVD->getType(); 3354 3355 if (T->isObjCObjectType()) { 3356 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3357 return NewVD->setInvalidDecl(); 3358 } 3359 3360 // Emit an error if an address space was applied to decl with local storage. 3361 // This includes arrays of objects with address space qualifiers, but not 3362 // automatic variables that point to other address spaces. 3363 // ISO/IEC TR 18037 S5.1.2 3364 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3365 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3366 return NewVD->setInvalidDecl(); 3367 } 3368 3369 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3370 && !NewVD->hasAttr<BlocksAttr>()) 3371 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3372 3373 bool isVM = T->isVariablyModifiedType(); 3374 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3375 NewVD->hasAttr<BlocksAttr>()) 3376 getCurFunction()->setHasBranchProtectedScope(); 3377 3378 if ((isVM && NewVD->hasLinkage()) || 3379 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3380 bool SizeIsNegative; 3381 llvm::APSInt Oversized; 3382 QualType FixedTy = 3383 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3384 Oversized); 3385 3386 if (FixedTy.isNull() && T->isVariableArrayType()) { 3387 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3388 // FIXME: This won't give the correct result for 3389 // int a[10][n]; 3390 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3391 3392 if (NewVD->isFileVarDecl()) 3393 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3394 << SizeRange; 3395 else if (NewVD->getStorageClass() == SC_Static) 3396 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3397 << SizeRange; 3398 else 3399 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3400 << SizeRange; 3401 return NewVD->setInvalidDecl(); 3402 } 3403 3404 if (FixedTy.isNull()) { 3405 if (NewVD->isFileVarDecl()) 3406 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3407 else 3408 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3409 return NewVD->setInvalidDecl(); 3410 } 3411 3412 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3413 NewVD->setType(FixedTy); 3414 } 3415 3416 if (Previous.empty() && NewVD->isExternC()) { 3417 // Since we did not find anything by this name and we're declaring 3418 // an extern "C" variable, look for a non-visible extern "C" 3419 // declaration with the same name. 3420 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3421 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3422 if (Pos != LocallyScopedExternalDecls.end()) 3423 Previous.addDecl(Pos->second); 3424 } 3425 3426 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3427 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3428 << T; 3429 return NewVD->setInvalidDecl(); 3430 } 3431 3432 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3433 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3434 return NewVD->setInvalidDecl(); 3435 } 3436 3437 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3438 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3439 return NewVD->setInvalidDecl(); 3440 } 3441 3442 // Function pointers and references cannot have qualified function type, only 3443 // function pointer-to-members can do that. 3444 QualType Pointee; 3445 unsigned PtrOrRef = 0; 3446 if (const PointerType *Ptr = T->getAs<PointerType>()) 3447 Pointee = Ptr->getPointeeType(); 3448 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3449 Pointee = Ref->getPointeeType(); 3450 PtrOrRef = 1; 3451 } 3452 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3453 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3454 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3455 << PtrOrRef; 3456 return NewVD->setInvalidDecl(); 3457 } 3458 3459 if (!Previous.empty()) { 3460 Redeclaration = true; 3461 MergeVarDecl(NewVD, Previous); 3462 } 3463} 3464 3465/// \brief Data used with FindOverriddenMethod 3466struct FindOverriddenMethodData { 3467 Sema *S; 3468 CXXMethodDecl *Method; 3469}; 3470 3471/// \brief Member lookup function that determines whether a given C++ 3472/// method overrides a method in a base class, to be used with 3473/// CXXRecordDecl::lookupInBases(). 3474static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3475 CXXBasePath &Path, 3476 void *UserData) { 3477 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3478 3479 FindOverriddenMethodData *Data 3480 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3481 3482 DeclarationName Name = Data->Method->getDeclName(); 3483 3484 // FIXME: Do we care about other names here too? 3485 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3486 // We really want to find the base class destructor here. 3487 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3488 CanQualType CT = Data->S->Context.getCanonicalType(T); 3489 3490 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3491 } 3492 3493 for (Path.Decls = BaseRecord->lookup(Name); 3494 Path.Decls.first != Path.Decls.second; 3495 ++Path.Decls.first) { 3496 NamedDecl *D = *Path.Decls.first; 3497 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3498 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3499 return true; 3500 } 3501 } 3502 3503 return false; 3504} 3505 3506/// AddOverriddenMethods - See if a method overrides any in the base classes, 3507/// and if so, check that it's a valid override and remember it. 3508bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3509 // Look for virtual methods in base classes that this method might override. 3510 CXXBasePaths Paths; 3511 FindOverriddenMethodData Data; 3512 Data.Method = MD; 3513 Data.S = this; 3514 bool AddedAny = false; 3515 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3516 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3517 E = Paths.found_decls_end(); I != E; ++I) { 3518 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3519 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3520 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3521 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 3522 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3523 AddedAny = true; 3524 } 3525 } 3526 } 3527 } 3528 3529 return AddedAny; 3530} 3531 3532static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3533 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3534 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3535 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3536 assert(!Prev.isAmbiguous() && 3537 "Cannot have an ambiguity in previous-declaration lookup"); 3538 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3539 Func != FuncEnd; ++Func) { 3540 if (isa<FunctionDecl>(*Func) && 3541 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3542 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3543 } 3544} 3545 3546NamedDecl* 3547Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3548 QualType R, TypeSourceInfo *TInfo, 3549 LookupResult &Previous, 3550 MultiTemplateParamsArg TemplateParamLists, 3551 bool IsFunctionDefinition, bool &Redeclaration) { 3552 assert(R.getTypePtr()->isFunctionType()); 3553 3554 // TODO: consider using NameInfo for diagnostic. 3555 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3556 DeclarationName Name = NameInfo.getName(); 3557 FunctionDecl::StorageClass SC = SC_None; 3558 switch (D.getDeclSpec().getStorageClassSpec()) { 3559 default: assert(0 && "Unknown storage class!"); 3560 case DeclSpec::SCS_auto: 3561 case DeclSpec::SCS_register: 3562 case DeclSpec::SCS_mutable: 3563 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3564 diag::err_typecheck_sclass_func); 3565 D.setInvalidType(); 3566 break; 3567 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3568 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3569 case DeclSpec::SCS_static: { 3570 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3571 // C99 6.7.1p5: 3572 // The declaration of an identifier for a function that has 3573 // block scope shall have no explicit storage-class specifier 3574 // other than extern 3575 // See also (C++ [dcl.stc]p4). 3576 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3577 diag::err_static_block_func); 3578 SC = SC_None; 3579 } else 3580 SC = SC_Static; 3581 break; 3582 } 3583 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3584 } 3585 3586 if (D.getDeclSpec().isThreadSpecified()) 3587 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3588 3589 // Do not allow returning a objc interface by-value. 3590 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3591 Diag(D.getIdentifierLoc(), 3592 diag::err_object_cannot_be_passed_returned_by_value) << 0 3593 << R->getAs<FunctionType>()->getResultType(); 3594 D.setInvalidType(); 3595 } 3596 3597 FunctionDecl *NewFD; 3598 bool isInline = D.getDeclSpec().isInlineSpecified(); 3599 bool isFriend = false; 3600 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3601 FunctionDecl::StorageClass SCAsWritten 3602 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3603 FunctionTemplateDecl *FunctionTemplate = 0; 3604 bool isExplicitSpecialization = false; 3605 bool isFunctionTemplateSpecialization = false; 3606 unsigned NumMatchedTemplateParamLists = 0; 3607 3608 if (!getLangOptions().CPlusPlus) { 3609 // Determine whether the function was written with a 3610 // prototype. This true when: 3611 // - there is a prototype in the declarator, or 3612 // - the type R of the function is some kind of typedef or other reference 3613 // to a type name (which eventually refers to a function type). 3614 bool HasPrototype = 3615 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 3616 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3617 3618 NewFD = FunctionDecl::Create(Context, DC, 3619 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3620 HasPrototype); 3621 if (D.isInvalidType()) 3622 NewFD->setInvalidDecl(); 3623 3624 // Set the lexical context. 3625 NewFD->setLexicalDeclContext(CurContext); 3626 // Filter out previous declarations that don't match the scope. 3627 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3628 } else { 3629 isFriend = D.getDeclSpec().isFriendSpecified(); 3630 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3631 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3632 bool isVirtualOkay = false; 3633 3634 // Check that the return type is not an abstract class type. 3635 // For record types, this is done by the AbstractClassUsageDiagnoser once 3636 // the class has been completely parsed. 3637 if (!DC->isRecord() && 3638 RequireNonAbstractType(D.getIdentifierLoc(), 3639 R->getAs<FunctionType>()->getResultType(), 3640 diag::err_abstract_type_in_decl, 3641 AbstractReturnType)) 3642 D.setInvalidType(); 3643 3644 3645 if (isFriend) { 3646 // C++ [class.friend]p5 3647 // A function can be defined in a friend declaration of a 3648 // class . . . . Such a function is implicitly inline. 3649 isInline |= IsFunctionDefinition; 3650 } 3651 3652 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3653 // This is a C++ constructor declaration. 3654 assert(DC->isRecord() && 3655 "Constructors can only be declared in a member context"); 3656 3657 R = CheckConstructorDeclarator(D, R, SC); 3658 3659 // Create the new declaration 3660 NewFD = CXXConstructorDecl::Create(Context, 3661 cast<CXXRecordDecl>(DC), 3662 NameInfo, R, TInfo, 3663 isExplicit, isInline, 3664 /*isImplicitlyDeclared=*/false); 3665 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3666 // This is a C++ destructor declaration. 3667 if (DC->isRecord()) { 3668 R = CheckDestructorDeclarator(D, R, SC); 3669 3670 NewFD = CXXDestructorDecl::Create(Context, 3671 cast<CXXRecordDecl>(DC), 3672 NameInfo, R, TInfo, 3673 isInline, 3674 /*isImplicitlyDeclared=*/false); 3675 isVirtualOkay = true; 3676 } else { 3677 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3678 3679 // Create a FunctionDecl to satisfy the function definition parsing 3680 // code path. 3681 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3682 Name, R, TInfo, SC, SCAsWritten, isInline, 3683 /*hasPrototype=*/true); 3684 D.setInvalidType(); 3685 } 3686 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3687 if (!DC->isRecord()) { 3688 Diag(D.getIdentifierLoc(), 3689 diag::err_conv_function_not_member); 3690 return 0; 3691 } 3692 3693 CheckConversionDeclarator(D, R, SC); 3694 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3695 NameInfo, R, TInfo, 3696 isInline, isExplicit); 3697 3698 isVirtualOkay = true; 3699 } else if (DC->isRecord()) { 3700 // If the of the function is the same as the name of the record, then this 3701 // must be an invalid constructor that has a return type. 3702 // (The parser checks for a return type and makes the declarator a 3703 // constructor if it has no return type). 3704 // must have an invalid constructor that has a return type 3705 if (Name.getAsIdentifierInfo() && 3706 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3707 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3708 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3709 << SourceRange(D.getIdentifierLoc()); 3710 return 0; 3711 } 3712 3713 bool isStatic = SC == SC_Static; 3714 3715 // [class.free]p1: 3716 // Any allocation function for a class T is a static member 3717 // (even if not explicitly declared static). 3718 if (Name.getCXXOverloadedOperator() == OO_New || 3719 Name.getCXXOverloadedOperator() == OO_Array_New) 3720 isStatic = true; 3721 3722 // [class.free]p6 Any deallocation function for a class X is a static member 3723 // (even if not explicitly declared static). 3724 if (Name.getCXXOverloadedOperator() == OO_Delete || 3725 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3726 isStatic = true; 3727 3728 // This is a C++ method declaration. 3729 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3730 NameInfo, R, TInfo, 3731 isStatic, SCAsWritten, isInline); 3732 3733 isVirtualOkay = !isStatic; 3734 } else { 3735 // Determine whether the function was written with a 3736 // prototype. This true when: 3737 // - we're in C++ (where every function has a prototype), 3738 NewFD = FunctionDecl::Create(Context, DC, 3739 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3740 true/*HasPrototype*/); 3741 } 3742 SetNestedNameSpecifier(NewFD, D); 3743 isExplicitSpecialization = false; 3744 isFunctionTemplateSpecialization = false; 3745 NumMatchedTemplateParamLists = TemplateParamLists.size(); 3746 if (D.isInvalidType()) 3747 NewFD->setInvalidDecl(); 3748 3749 // Set the lexical context. If the declarator has a C++ 3750 // scope specifier, or is the object of a friend declaration, the 3751 // lexical context will be different from the semantic context. 3752 NewFD->setLexicalDeclContext(CurContext); 3753 3754 // Match up the template parameter lists with the scope specifier, then 3755 // determine whether we have a template or a template specialization. 3756 bool Invalid = false; 3757 if (TemplateParameterList *TemplateParams 3758 = MatchTemplateParametersToScopeSpecifier( 3759 D.getDeclSpec().getSourceRange().getBegin(), 3760 D.getCXXScopeSpec(), 3761 TemplateParamLists.get(), 3762 TemplateParamLists.size(), 3763 isFriend, 3764 isExplicitSpecialization, 3765 Invalid)) { 3766 // All but one template parameter lists have been matching. 3767 --NumMatchedTemplateParamLists; 3768 3769 if (TemplateParams->size() > 0) { 3770 // This is a function template 3771 3772 // Check that we can declare a template here. 3773 if (CheckTemplateDeclScope(S, TemplateParams)) 3774 return 0; 3775 3776 // A destructor cannot be a template. 3777 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3778 Diag(NewFD->getLocation(), diag::err_destructor_template); 3779 return 0; 3780 } 3781 3782 3783 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3784 NewFD->getLocation(), 3785 Name, TemplateParams, 3786 NewFD); 3787 FunctionTemplate->setLexicalDeclContext(CurContext); 3788 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3789 } else { 3790 // This is a function template specialization. 3791 isFunctionTemplateSpecialization = true; 3792 3793 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3794 if (isFriend && isFunctionTemplateSpecialization) { 3795 // We want to remove the "template<>", found here. 3796 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3797 3798 // If we remove the template<> and the name is not a 3799 // template-id, we're actually silently creating a problem: 3800 // the friend declaration will refer to an untemplated decl, 3801 // and clearly the user wants a template specialization. So 3802 // we need to insert '<>' after the name. 3803 SourceLocation InsertLoc; 3804 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3805 InsertLoc = D.getName().getSourceRange().getEnd(); 3806 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3807 } 3808 3809 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3810 << Name << RemoveRange 3811 << FixItHint::CreateRemoval(RemoveRange) 3812 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3813 } 3814 } 3815 } 3816 3817 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3818 NewFD->setTemplateParameterListsInfo(Context, 3819 NumMatchedTemplateParamLists, 3820 TemplateParamLists.release()); 3821 } 3822 3823 if (Invalid) { 3824 NewFD->setInvalidDecl(); 3825 if (FunctionTemplate) 3826 FunctionTemplate->setInvalidDecl(); 3827 } 3828 3829 // C++ [dcl.fct.spec]p5: 3830 // The virtual specifier shall only be used in declarations of 3831 // nonstatic class member functions that appear within a 3832 // member-specification of a class declaration; see 10.3. 3833 // 3834 if (isVirtual && !NewFD->isInvalidDecl()) { 3835 if (!isVirtualOkay) { 3836 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3837 diag::err_virtual_non_function); 3838 } else if (!CurContext->isRecord()) { 3839 // 'virtual' was specified outside of the class. 3840 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3841 diag::err_virtual_out_of_class) 3842 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3843 } else if (NewFD->getDescribedFunctionTemplate()) { 3844 // C++ [temp.mem]p3: 3845 // A member function template shall not be virtual. 3846 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3847 diag::err_virtual_member_function_template) 3848 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3849 } else { 3850 // Okay: Add virtual to the method. 3851 NewFD->setVirtualAsWritten(true); 3852 } 3853 } 3854 3855 // C++ [dcl.fct.spec]p3: 3856 // The inline specifier shall not appear on a block scope function declaration. 3857 if (isInline && !NewFD->isInvalidDecl()) { 3858 if (CurContext->isFunctionOrMethod()) { 3859 // 'inline' is not allowed on block scope function declaration. 3860 Diag(D.getDeclSpec().getInlineSpecLoc(), 3861 diag::err_inline_declaration_block_scope) << Name 3862 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3863 } 3864 } 3865 3866 // C++ [dcl.fct.spec]p6: 3867 // The explicit specifier shall be used only in the declaration of a 3868 // constructor or conversion function within its class definition; see 12.3.1 3869 // and 12.3.2. 3870 if (isExplicit && !NewFD->isInvalidDecl()) { 3871 if (!CurContext->isRecord()) { 3872 // 'explicit' was specified outside of the class. 3873 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3874 diag::err_explicit_out_of_class) 3875 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3876 } else if (!isa<CXXConstructorDecl>(NewFD) && 3877 !isa<CXXConversionDecl>(NewFD)) { 3878 // 'explicit' was specified on a function that wasn't a constructor 3879 // or conversion function. 3880 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3881 diag::err_explicit_non_ctor_or_conv_function) 3882 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3883 } 3884 } 3885 3886 // Filter out previous declarations that don't match the scope. 3887 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3888 3889 if (isFriend) { 3890 // For now, claim that the objects have no previous declaration. 3891 if (FunctionTemplate) { 3892 FunctionTemplate->setObjectOfFriendDecl(false); 3893 FunctionTemplate->setAccess(AS_public); 3894 } 3895 NewFD->setObjectOfFriendDecl(false); 3896 NewFD->setAccess(AS_public); 3897 } 3898 3899 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 3900 // A method is implicitly inline if it's defined in its class 3901 // definition. 3902 NewFD->setImplicitlyInline(); 3903 } 3904 3905 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 3906 !CurContext->isRecord()) { 3907 // C++ [class.static]p1: 3908 // A data or function member of a class may be declared static 3909 // in a class definition, in which case it is a static member of 3910 // the class. 3911 3912 // Complain about the 'static' specifier if it's on an out-of-line 3913 // member function definition. 3914 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3915 diag::err_static_out_of_line) 3916 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3917 } 3918 } 3919 3920 // Handle GNU asm-label extension (encoded as an attribute). 3921 if (Expr *E = (Expr*) D.getAsmLabel()) { 3922 // The parser guarantees this is a string. 3923 StringLiteral *SE = cast<StringLiteral>(E); 3924 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 3925 SE->getString())); 3926 } 3927 3928 // Copy the parameter declarations from the declarator D to the function 3929 // declaration NewFD, if they are available. First scavenge them into Params. 3930 llvm::SmallVector<ParmVarDecl*, 16> Params; 3931 if (D.isFunctionDeclarator()) { 3932 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 3933 3934 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3935 // function that takes no arguments, not a function that takes a 3936 // single void argument. 3937 // We let through "const void" here because Sema::GetTypeForDeclarator 3938 // already checks for that case. 3939 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3940 FTI.ArgInfo[0].Param && 3941 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 3942 // Empty arg list, don't push any params. 3943 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 3944 3945 // In C++, the empty parameter-type-list must be spelled "void"; a 3946 // typedef of void is not permitted. 3947 if (getLangOptions().CPlusPlus && 3948 Param->getType().getUnqualifiedType() != Context.VoidTy) 3949 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3950 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3951 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3952 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 3953 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3954 Param->setDeclContext(NewFD); 3955 Params.push_back(Param); 3956 3957 if (Param->isInvalidDecl()) 3958 NewFD->setInvalidDecl(); 3959 } 3960 } 3961 3962 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3963 // When we're declaring a function with a typedef, typeof, etc as in the 3964 // following example, we'll need to synthesize (unnamed) 3965 // parameters for use in the declaration. 3966 // 3967 // @code 3968 // typedef void fn(int); 3969 // fn f; 3970 // @endcode 3971 3972 // Synthesize a parameter for each argument type. 3973 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3974 AE = FT->arg_type_end(); AI != AE; ++AI) { 3975 ParmVarDecl *Param = 3976 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3977 Params.push_back(Param); 3978 } 3979 } else { 3980 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3981 "Should not need args for typedef of non-prototype fn"); 3982 } 3983 // Finally, we know we have the right number of parameters, install them. 3984 NewFD->setParams(Params.data(), Params.size()); 3985 3986 // Process the non-inheritable attributes on this declaration. 3987 ProcessDeclAttributes(S, NewFD, D, 3988 /*NonInheritable=*/true, /*Inheritable=*/false); 3989 3990 if (!getLangOptions().CPlusPlus) { 3991 // Perform semantic checking on the function declaration. 3992 bool isExplctSpecialization=false; 3993 CheckFunctionDeclaration(S, NewFD, Previous, isExplctSpecialization, 3994 Redeclaration); 3995 assert((NewFD->isInvalidDecl() || !Redeclaration || 3996 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3997 "previous declaration set still overloaded"); 3998 } else { 3999 // If the declarator is a template-id, translate the parser's template 4000 // argument list into our AST format. 4001 bool HasExplicitTemplateArgs = false; 4002 TemplateArgumentListInfo TemplateArgs; 4003 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4004 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4005 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4006 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4007 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4008 TemplateId->getTemplateArgs(), 4009 TemplateId->NumArgs); 4010 translateTemplateArguments(TemplateArgsPtr, 4011 TemplateArgs); 4012 TemplateArgsPtr.release(); 4013 4014 HasExplicitTemplateArgs = true; 4015 4016 if (FunctionTemplate) { 4017 // Function template with explicit template arguments. 4018 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4019 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4020 4021 HasExplicitTemplateArgs = false; 4022 } else if (!isFunctionTemplateSpecialization && 4023 !D.getDeclSpec().isFriendSpecified()) { 4024 // We have encountered something that the user meant to be a 4025 // specialization (because it has explicitly-specified template 4026 // arguments) but that was not introduced with a "template<>" (or had 4027 // too few of them). 4028 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4029 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4030 << FixItHint::CreateInsertion( 4031 D.getDeclSpec().getSourceRange().getBegin(), 4032 "template<> "); 4033 isFunctionTemplateSpecialization = true; 4034 } else { 4035 // "friend void foo<>(int);" is an implicit specialization decl. 4036 isFunctionTemplateSpecialization = true; 4037 } 4038 } else if (isFriend && isFunctionTemplateSpecialization) { 4039 // This combination is only possible in a recovery case; the user 4040 // wrote something like: 4041 // template <> friend void foo(int); 4042 // which we're recovering from as if the user had written: 4043 // friend void foo<>(int); 4044 // Go ahead and fake up a template id. 4045 HasExplicitTemplateArgs = true; 4046 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4047 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4048 } 4049 4050 // If it's a friend (and only if it's a friend), it's possible 4051 // that either the specialized function type or the specialized 4052 // template is dependent, and therefore matching will fail. In 4053 // this case, don't check the specialization yet. 4054 if (isFunctionTemplateSpecialization && isFriend && 4055 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4056 assert(HasExplicitTemplateArgs && 4057 "friend function specialization without template args"); 4058 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4059 Previous)) 4060 NewFD->setInvalidDecl(); 4061 } else if (isFunctionTemplateSpecialization) { 4062 if (CheckFunctionTemplateSpecialization(NewFD, 4063 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4064 Previous)) 4065 NewFD->setInvalidDecl(); 4066 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4067 if (CheckMemberSpecialization(NewFD, Previous)) 4068 NewFD->setInvalidDecl(); 4069 } 4070 4071 // Perform semantic checking on the function declaration. 4072 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4073 Redeclaration); 4074 4075 assert((NewFD->isInvalidDecl() || !Redeclaration || 4076 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4077 "previous declaration set still overloaded"); 4078 4079 NamedDecl *PrincipalDecl = (FunctionTemplate 4080 ? cast<NamedDecl>(FunctionTemplate) 4081 : NewFD); 4082 4083 if (isFriend && Redeclaration) { 4084 AccessSpecifier Access = AS_public; 4085 if (!NewFD->isInvalidDecl()) 4086 Access = NewFD->getPreviousDeclaration()->getAccess(); 4087 4088 NewFD->setAccess(Access); 4089 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4090 4091 PrincipalDecl->setObjectOfFriendDecl(true); 4092 } 4093 4094 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4095 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4096 PrincipalDecl->setNonMemberOperator(); 4097 4098 // If we have a function template, check the template parameter 4099 // list. This will check and merge default template arguments. 4100 if (FunctionTemplate) { 4101 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4102 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4103 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4104 D.getDeclSpec().isFriendSpecified() 4105 ? (IsFunctionDefinition 4106 ? TPC_FriendFunctionTemplateDefinition 4107 : TPC_FriendFunctionTemplate) 4108 : (D.getCXXScopeSpec().isSet() && 4109 DC && DC->isRecord() && 4110 DC->isDependentContext()) 4111 ? TPC_ClassTemplateMember 4112 : TPC_FunctionTemplate); 4113 } 4114 4115 if (NewFD->isInvalidDecl()) { 4116 // Ignore all the rest of this. 4117 } else if (!Redeclaration) { 4118 // Fake up an access specifier if it's supposed to be a class member. 4119 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4120 NewFD->setAccess(AS_public); 4121 4122 // Qualified decls generally require a previous declaration. 4123 if (D.getCXXScopeSpec().isSet()) { 4124 // ...with the major exception of templated-scope or 4125 // dependent-scope friend declarations. 4126 4127 // TODO: we currently also suppress this check in dependent 4128 // contexts because (1) the parameter depth will be off when 4129 // matching friend templates and (2) we might actually be 4130 // selecting a friend based on a dependent factor. But there 4131 // are situations where these conditions don't apply and we 4132 // can actually do this check immediately. 4133 if (isFriend && 4134 (NumMatchedTemplateParamLists || 4135 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4136 CurContext->isDependentContext())) { 4137 // ignore these 4138 } else { 4139 // The user tried to provide an out-of-line definition for a 4140 // function that is a member of a class or namespace, but there 4141 // was no such member function declared (C++ [class.mfct]p2, 4142 // C++ [namespace.memdef]p2). For example: 4143 // 4144 // class X { 4145 // void f() const; 4146 // }; 4147 // 4148 // void X::f() { } // ill-formed 4149 // 4150 // Complain about this problem, and attempt to suggest close 4151 // matches (e.g., those that differ only in cv-qualifiers and 4152 // whether the parameter types are references). 4153 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4154 << Name << DC << D.getCXXScopeSpec().getRange(); 4155 NewFD->setInvalidDecl(); 4156 4157 DiagnoseInvalidRedeclaration(*this, NewFD); 4158 } 4159 4160 // Unqualified local friend declarations are required to resolve 4161 // to something. 4162 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4163 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4164 NewFD->setInvalidDecl(); 4165 DiagnoseInvalidRedeclaration(*this, NewFD); 4166 } 4167 4168 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4169 !isFriend && !isFunctionTemplateSpecialization && 4170 !isExplicitSpecialization) { 4171 // An out-of-line member function declaration must also be a 4172 // definition (C++ [dcl.meaning]p1). 4173 // Note that this is not the case for explicit specializations of 4174 // function templates or member functions of class templates, per 4175 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4176 // for compatibility with old SWIG code which likes to generate them. 4177 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4178 << D.getCXXScopeSpec().getRange(); 4179 } 4180 } 4181 4182 4183 // Handle attributes. We need to have merged decls when handling attributes 4184 // (for example to check for conflicts, etc). 4185 // FIXME: This needs to happen before we merge declarations. Then, 4186 // let attribute merging cope with attribute conflicts. 4187 ProcessDeclAttributes(S, NewFD, D, 4188 /*NonInheritable=*/false, /*Inheritable=*/true); 4189 4190 // attributes declared post-definition are currently ignored 4191 // FIXME: This should happen during attribute merging 4192 if (Redeclaration && Previous.isSingleResult()) { 4193 const FunctionDecl *Def; 4194 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4195 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 4196 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4197 Diag(Def->getLocation(), diag::note_previous_definition); 4198 } 4199 } 4200 4201 AddKnownFunctionAttributes(NewFD); 4202 4203 if (NewFD->hasAttr<OverloadableAttr>() && 4204 !NewFD->getType()->getAs<FunctionProtoType>()) { 4205 Diag(NewFD->getLocation(), 4206 diag::err_attribute_overloadable_no_prototype) 4207 << NewFD; 4208 4209 // Turn this into a variadic function with no parameters. 4210 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4211 FunctionProtoType::ExtProtoInfo EPI; 4212 EPI.Variadic = true; 4213 EPI.ExtInfo = FT->getExtInfo(); 4214 4215 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4216 NewFD->setType(R); 4217 } 4218 4219 // If there's a #pragma GCC visibility in scope, and this isn't a class 4220 // member, set the visibility of this function. 4221 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4222 AddPushedVisibilityAttribute(NewFD); 4223 4224 // If this is a locally-scoped extern C function, update the 4225 // map of such names. 4226 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4227 && !NewFD->isInvalidDecl()) 4228 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4229 4230 // Set this FunctionDecl's range up to the right paren. 4231 NewFD->setLocEnd(D.getSourceRange().getEnd()); 4232 4233 if (getLangOptions().CPlusPlus) { 4234 if (FunctionTemplate) { 4235 if (NewFD->isInvalidDecl()) 4236 FunctionTemplate->setInvalidDecl(); 4237 return FunctionTemplate; 4238 } 4239 } 4240 4241 MarkUnusedFileScopedDecl(NewFD); 4242 4243 if (getLangOptions().CUDA) 4244 if (IdentifierInfo *II = NewFD->getIdentifier()) 4245 if (!NewFD->isInvalidDecl() && 4246 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4247 if (II->isStr("cudaConfigureCall")) { 4248 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4249 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4250 4251 Context.setcudaConfigureCallDecl(NewFD); 4252 } 4253 } 4254 4255 return NewFD; 4256} 4257 4258/// \brief Perform semantic checking of a new function declaration. 4259/// 4260/// Performs semantic analysis of the new function declaration 4261/// NewFD. This routine performs all semantic checking that does not 4262/// require the actual declarator involved in the declaration, and is 4263/// used both for the declaration of functions as they are parsed 4264/// (called via ActOnDeclarator) and for the declaration of functions 4265/// that have been instantiated via C++ template instantiation (called 4266/// via InstantiateDecl). 4267/// 4268/// \param IsExplicitSpecialiation whether this new function declaration is 4269/// an explicit specialization of the previous declaration. 4270/// 4271/// This sets NewFD->isInvalidDecl() to true if there was an error. 4272void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4273 LookupResult &Previous, 4274 bool IsExplicitSpecialization, 4275 bool &Redeclaration) { 4276 // If NewFD is already known erroneous, don't do any of this checking. 4277 if (NewFD->isInvalidDecl()) { 4278 // If this is a class member, mark the class invalid immediately. 4279 // This avoids some consistency errors later. 4280 if (isa<CXXMethodDecl>(NewFD)) 4281 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4282 4283 return; 4284 } 4285 4286 if (NewFD->getResultType()->isVariablyModifiedType()) { 4287 // Functions returning a variably modified type violate C99 6.7.5.2p2 4288 // because all functions have linkage. 4289 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4290 return NewFD->setInvalidDecl(); 4291 } 4292 4293 if (NewFD->isMain()) 4294 CheckMain(NewFD); 4295 4296 // Check for a previous declaration of this name. 4297 if (Previous.empty() && NewFD->isExternC()) { 4298 // Since we did not find anything by this name and we're declaring 4299 // an extern "C" function, look for a non-visible extern "C" 4300 // declaration with the same name. 4301 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4302 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4303 if (Pos != LocallyScopedExternalDecls.end()) 4304 Previous.addDecl(Pos->second); 4305 } 4306 4307 // Merge or overload the declaration with an existing declaration of 4308 // the same name, if appropriate. 4309 if (!Previous.empty()) { 4310 // Determine whether NewFD is an overload of PrevDecl or 4311 // a declaration that requires merging. If it's an overload, 4312 // there's no more work to do here; we'll just add the new 4313 // function to the scope. 4314 4315 NamedDecl *OldDecl = 0; 4316 if (!AllowOverloadingOfFunction(Previous, Context)) { 4317 Redeclaration = true; 4318 OldDecl = Previous.getFoundDecl(); 4319 } else { 4320 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4321 /*NewIsUsingDecl*/ false)) { 4322 case Ovl_Match: 4323 Redeclaration = true; 4324 break; 4325 4326 case Ovl_NonFunction: 4327 Redeclaration = true; 4328 break; 4329 4330 case Ovl_Overload: 4331 Redeclaration = false; 4332 break; 4333 } 4334 4335 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4336 // If a function name is overloadable in C, then every function 4337 // with that name must be marked "overloadable". 4338 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4339 << Redeclaration << NewFD; 4340 NamedDecl *OverloadedDecl = 0; 4341 if (Redeclaration) 4342 OverloadedDecl = OldDecl; 4343 else if (!Previous.empty()) 4344 OverloadedDecl = Previous.getRepresentativeDecl(); 4345 if (OverloadedDecl) 4346 Diag(OverloadedDecl->getLocation(), 4347 diag::note_attribute_overloadable_prev_overload); 4348 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4349 Context)); 4350 } 4351 } 4352 4353 if (Redeclaration) { 4354 // NewFD and OldDecl represent declarations that need to be 4355 // merged. 4356 if (MergeFunctionDecl(NewFD, OldDecl)) 4357 return NewFD->setInvalidDecl(); 4358 4359 Previous.clear(); 4360 Previous.addDecl(OldDecl); 4361 4362 if (FunctionTemplateDecl *OldTemplateDecl 4363 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4364 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4365 FunctionTemplateDecl *NewTemplateDecl 4366 = NewFD->getDescribedFunctionTemplate(); 4367 assert(NewTemplateDecl && "Template/non-template mismatch"); 4368 if (CXXMethodDecl *Method 4369 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4370 Method->setAccess(OldTemplateDecl->getAccess()); 4371 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4372 } 4373 4374 // If this is an explicit specialization of a member that is a function 4375 // template, mark it as a member specialization. 4376 if (IsExplicitSpecialization && 4377 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4378 NewTemplateDecl->setMemberSpecialization(); 4379 assert(OldTemplateDecl->isMemberSpecialization()); 4380 } 4381 } else { 4382 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4383 NewFD->setAccess(OldDecl->getAccess()); 4384 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4385 } 4386 } 4387 } 4388 4389 // Semantic checking for this function declaration (in isolation). 4390 if (getLangOptions().CPlusPlus) { 4391 // C++-specific checks. 4392 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4393 CheckConstructor(Constructor); 4394 } else if (CXXDestructorDecl *Destructor = 4395 dyn_cast<CXXDestructorDecl>(NewFD)) { 4396 CXXRecordDecl *Record = Destructor->getParent(); 4397 QualType ClassType = Context.getTypeDeclType(Record); 4398 4399 // FIXME: Shouldn't we be able to perform this check even when the class 4400 // type is dependent? Both gcc and edg can handle that. 4401 if (!ClassType->isDependentType()) { 4402 DeclarationName Name 4403 = Context.DeclarationNames.getCXXDestructorName( 4404 Context.getCanonicalType(ClassType)); 4405 if (NewFD->getDeclName() != Name) { 4406 Diag(NewFD->getLocation(), diag::err_destructor_name); 4407 return NewFD->setInvalidDecl(); 4408 } 4409 } 4410 } else if (CXXConversionDecl *Conversion 4411 = dyn_cast<CXXConversionDecl>(NewFD)) { 4412 ActOnConversionDeclarator(Conversion); 4413 } 4414 4415 // Find any virtual functions that this function overrides. 4416 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4417 if (!Method->isFunctionTemplateSpecialization() && 4418 !Method->getDescribedFunctionTemplate()) { 4419 if (AddOverriddenMethods(Method->getParent(), Method)) { 4420 // If the function was marked as "static", we have a problem. 4421 if (NewFD->getStorageClass() == SC_Static) { 4422 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4423 << NewFD->getDeclName(); 4424 for (CXXMethodDecl::method_iterator 4425 Overridden = Method->begin_overridden_methods(), 4426 OverriddenEnd = Method->end_overridden_methods(); 4427 Overridden != OverriddenEnd; 4428 ++Overridden) { 4429 Diag((*Overridden)->getLocation(), 4430 diag::note_overridden_virtual_function); 4431 } 4432 } 4433 } 4434 } 4435 } 4436 4437 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4438 if (NewFD->isOverloadedOperator() && 4439 CheckOverloadedOperatorDeclaration(NewFD)) 4440 return NewFD->setInvalidDecl(); 4441 4442 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4443 if (NewFD->getLiteralIdentifier() && 4444 CheckLiteralOperatorDeclaration(NewFD)) 4445 return NewFD->setInvalidDecl(); 4446 4447 // In C++, check default arguments now that we have merged decls. Unless 4448 // the lexical context is the class, because in this case this is done 4449 // during delayed parsing anyway. 4450 if (!CurContext->isRecord()) 4451 CheckCXXDefaultArguments(NewFD); 4452 4453 // If this function declares a builtin function, check the type of this 4454 // declaration against the expected type for the builtin. 4455 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 4456 ASTContext::GetBuiltinTypeError Error; 4457 QualType T = Context.GetBuiltinType(BuiltinID, Error); 4458 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 4459 // The type of this function differs from the type of the builtin, 4460 // so forget about the builtin entirely. 4461 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 4462 } 4463 } 4464 } 4465} 4466 4467void Sema::CheckMain(FunctionDecl* FD) { 4468 // C++ [basic.start.main]p3: A program that declares main to be inline 4469 // or static is ill-formed. 4470 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4471 // shall not appear in a declaration of main. 4472 // static main is not an error under C99, but we should warn about it. 4473 bool isInline = FD->isInlineSpecified(); 4474 bool isStatic = FD->getStorageClass() == SC_Static; 4475 if (isInline || isStatic) { 4476 unsigned diagID = diag::warn_unusual_main_decl; 4477 if (isInline || getLangOptions().CPlusPlus) 4478 diagID = diag::err_unusual_main_decl; 4479 4480 int which = isStatic + (isInline << 1) - 1; 4481 Diag(FD->getLocation(), diagID) << which; 4482 } 4483 4484 QualType T = FD->getType(); 4485 assert(T->isFunctionType() && "function decl is not of function type"); 4486 const FunctionType* FT = T->getAs<FunctionType>(); 4487 4488 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4489 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 4490 FD->setInvalidDecl(true); 4491 } 4492 4493 // Treat protoless main() as nullary. 4494 if (isa<FunctionNoProtoType>(FT)) return; 4495 4496 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4497 unsigned nparams = FTP->getNumArgs(); 4498 assert(FD->getNumParams() == nparams); 4499 4500 bool HasExtraParameters = (nparams > 3); 4501 4502 // Darwin passes an undocumented fourth argument of type char**. If 4503 // other platforms start sprouting these, the logic below will start 4504 // getting shifty. 4505 if (nparams == 4 && 4506 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4507 HasExtraParameters = false; 4508 4509 if (HasExtraParameters) { 4510 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4511 FD->setInvalidDecl(true); 4512 nparams = 3; 4513 } 4514 4515 // FIXME: a lot of the following diagnostics would be improved 4516 // if we had some location information about types. 4517 4518 QualType CharPP = 4519 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4520 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4521 4522 for (unsigned i = 0; i < nparams; ++i) { 4523 QualType AT = FTP->getArgType(i); 4524 4525 bool mismatch = true; 4526 4527 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4528 mismatch = false; 4529 else if (Expected[i] == CharPP) { 4530 // As an extension, the following forms are okay: 4531 // char const ** 4532 // char const * const * 4533 // char * const * 4534 4535 QualifierCollector qs; 4536 const PointerType* PT; 4537 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4538 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4539 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4540 qs.removeConst(); 4541 mismatch = !qs.empty(); 4542 } 4543 } 4544 4545 if (mismatch) { 4546 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4547 // TODO: suggest replacing given type with expected type 4548 FD->setInvalidDecl(true); 4549 } 4550 } 4551 4552 if (nparams == 1 && !FD->isInvalidDecl()) { 4553 Diag(FD->getLocation(), diag::warn_main_one_arg); 4554 } 4555 4556 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 4557 Diag(FD->getLocation(), diag::err_main_template_decl); 4558 FD->setInvalidDecl(); 4559 } 4560} 4561 4562bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4563 // FIXME: Need strict checking. In C89, we need to check for 4564 // any assignment, increment, decrement, function-calls, or 4565 // commas outside of a sizeof. In C99, it's the same list, 4566 // except that the aforementioned are allowed in unevaluated 4567 // expressions. Everything else falls under the 4568 // "may accept other forms of constant expressions" exception. 4569 // (We never end up here for C++, so the constant expression 4570 // rules there don't matter.) 4571 if (Init->isConstantInitializer(Context, false)) 4572 return false; 4573 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4574 << Init->getSourceRange(); 4575 return true; 4576} 4577 4578/// AddInitializerToDecl - Adds the initializer Init to the 4579/// declaration dcl. If DirectInit is true, this is C++ direct 4580/// initialization rather than copy initialization. 4581void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 4582 bool DirectInit, bool TypeMayContainAuto) { 4583 // If there is no declaration, there was an error parsing it. Just ignore 4584 // the initializer. 4585 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 4586 return; 4587 4588 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4589 // With declarators parsed the way they are, the parser cannot 4590 // distinguish between a normal initializer and a pure-specifier. 4591 // Thus this grotesque test. 4592 IntegerLiteral *IL; 4593 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4594 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4595 CheckPureMethod(Method, Init->getSourceRange()); 4596 else { 4597 Diag(Method->getLocation(), diag::err_member_function_initialization) 4598 << Method->getDeclName() << Init->getSourceRange(); 4599 Method->setInvalidDecl(); 4600 } 4601 return; 4602 } 4603 4604 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4605 if (!VDecl) { 4606 if (getLangOptions().CPlusPlus && 4607 RealDecl->getLexicalDeclContext()->isRecord() && 4608 isa<NamedDecl>(RealDecl)) 4609 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4610 else 4611 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4612 RealDecl->setInvalidDecl(); 4613 return; 4614 } 4615 4616 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 4617 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 4618 QualType DeducedType; 4619 if (!DeduceAutoType(VDecl->getType(), Init, DeducedType)) { 4620 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 4621 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 4622 << Init->getSourceRange(); 4623 RealDecl->setInvalidDecl(); 4624 return; 4625 } 4626 VDecl->setType(DeducedType); 4627 4628 // If this is a redeclaration, check that the type we just deduced matches 4629 // the previously declared type. 4630 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 4631 MergeVarDeclTypes(VDecl, Old); 4632 } 4633 4634 4635 // A definition must end up with a complete type, which means it must be 4636 // complete with the restriction that an array type might be completed by the 4637 // initializer; note that later code assumes this restriction. 4638 QualType BaseDeclType = VDecl->getType(); 4639 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4640 BaseDeclType = Array->getElementType(); 4641 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4642 diag::err_typecheck_decl_incomplete_type)) { 4643 RealDecl->setInvalidDecl(); 4644 return; 4645 } 4646 4647 // The variable can not have an abstract class type. 4648 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4649 diag::err_abstract_type_in_decl, 4650 AbstractVariableType)) 4651 VDecl->setInvalidDecl(); 4652 4653 const VarDecl *Def; 4654 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4655 Diag(VDecl->getLocation(), diag::err_redefinition) 4656 << VDecl->getDeclName(); 4657 Diag(Def->getLocation(), diag::note_previous_definition); 4658 VDecl->setInvalidDecl(); 4659 return; 4660 } 4661 4662 const VarDecl* PrevInit = 0; 4663 if (getLangOptions().CPlusPlus) { 4664 // C++ [class.static.data]p4 4665 // If a static data member is of const integral or const 4666 // enumeration type, its declaration in the class definition can 4667 // specify a constant-initializer which shall be an integral 4668 // constant expression (5.19). In that case, the member can appear 4669 // in integral constant expressions. The member shall still be 4670 // defined in a namespace scope if it is used in the program and the 4671 // namespace scope definition shall not contain an initializer. 4672 // 4673 // We already performed a redefinition check above, but for static 4674 // data members we also need to check whether there was an in-class 4675 // declaration with an initializer. 4676 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4677 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4678 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4679 return; 4680 } 4681 4682 if (VDecl->hasLocalStorage()) 4683 getCurFunction()->setHasBranchProtectedScope(); 4684 4685 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 4686 VDecl->setInvalidDecl(); 4687 return; 4688 } 4689 } 4690 4691 // Capture the variable that is being initialized and the style of 4692 // initialization. 4693 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4694 4695 // FIXME: Poor source location information. 4696 InitializationKind Kind 4697 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4698 Init->getLocStart(), 4699 Init->getLocEnd()) 4700 : InitializationKind::CreateCopy(VDecl->getLocation(), 4701 Init->getLocStart()); 4702 4703 // Get the decls type and save a reference for later, since 4704 // CheckInitializerTypes may change it. 4705 QualType DclT = VDecl->getType(), SavT = DclT; 4706 if (VDecl->isLocalVarDecl()) { 4707 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4708 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4709 VDecl->setInvalidDecl(); 4710 } else if (!VDecl->isInvalidDecl()) { 4711 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4712 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4713 MultiExprArg(*this, &Init, 1), 4714 &DclT); 4715 if (Result.isInvalid()) { 4716 VDecl->setInvalidDecl(); 4717 return; 4718 } 4719 4720 Init = Result.takeAs<Expr>(); 4721 4722 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4723 // Don't check invalid declarations to avoid emitting useless diagnostics. 4724 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4725 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4726 CheckForConstantInitializer(Init, DclT); 4727 } 4728 } 4729 } else if (VDecl->isStaticDataMember() && 4730 VDecl->getLexicalDeclContext()->isRecord()) { 4731 // This is an in-class initialization for a static data member, e.g., 4732 // 4733 // struct S { 4734 // static const int value = 17; 4735 // }; 4736 4737 // Try to perform the initialization regardless. 4738 if (!VDecl->isInvalidDecl()) { 4739 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4740 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4741 MultiExprArg(*this, &Init, 1), 4742 &DclT); 4743 if (Result.isInvalid()) { 4744 VDecl->setInvalidDecl(); 4745 return; 4746 } 4747 4748 Init = Result.takeAs<Expr>(); 4749 } 4750 4751 // C++ [class.mem]p4: 4752 // A member-declarator can contain a constant-initializer only 4753 // if it declares a static member (9.4) of const integral or 4754 // const enumeration type, see 9.4.2. 4755 QualType T = VDecl->getType(); 4756 4757 // Do nothing on dependent types. 4758 if (T->isDependentType()) { 4759 4760 // Require constness. 4761 } else if (!T.isConstQualified()) { 4762 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4763 << Init->getSourceRange(); 4764 VDecl->setInvalidDecl(); 4765 4766 // We allow integer constant expressions in all cases. 4767 } else if (T->isIntegralOrEnumerationType()) { 4768 if (!Init->isValueDependent()) { 4769 // Check whether the expression is a constant expression. 4770 llvm::APSInt Value; 4771 SourceLocation Loc; 4772 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4773 Diag(Loc, diag::err_in_class_initializer_non_constant) 4774 << Init->getSourceRange(); 4775 VDecl->setInvalidDecl(); 4776 } 4777 } 4778 4779 // We allow floating-point constants as an extension in C++03, and 4780 // C++0x has far more complicated rules that we don't really 4781 // implement fully. 4782 } else { 4783 bool Allowed = false; 4784 if (getLangOptions().CPlusPlus0x) { 4785 Allowed = T->isLiteralType(); 4786 } else if (T->isFloatingType()) { // also permits complex, which is ok 4787 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4788 << T << Init->getSourceRange(); 4789 Allowed = true; 4790 } 4791 4792 if (!Allowed) { 4793 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4794 << T << Init->getSourceRange(); 4795 VDecl->setInvalidDecl(); 4796 4797 // TODO: there are probably expressions that pass here that shouldn't. 4798 } else if (!Init->isValueDependent() && 4799 !Init->isConstantInitializer(Context, false)) { 4800 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4801 << Init->getSourceRange(); 4802 VDecl->setInvalidDecl(); 4803 } 4804 } 4805 } else if (VDecl->isFileVarDecl()) { 4806 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4807 (!getLangOptions().CPlusPlus || 4808 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4809 Diag(VDecl->getLocation(), diag::warn_extern_init); 4810 if (!VDecl->isInvalidDecl()) { 4811 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4812 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4813 MultiExprArg(*this, &Init, 1), 4814 &DclT); 4815 if (Result.isInvalid()) { 4816 VDecl->setInvalidDecl(); 4817 return; 4818 } 4819 4820 Init = Result.takeAs<Expr>(); 4821 } 4822 4823 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4824 // Don't check invalid declarations to avoid emitting useless diagnostics. 4825 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4826 // C99 6.7.8p4. All file scoped initializers need to be constant. 4827 CheckForConstantInitializer(Init, DclT); 4828 } 4829 } 4830 // If the type changed, it means we had an incomplete type that was 4831 // completed by the initializer. For example: 4832 // int ary[] = { 1, 3, 5 }; 4833 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4834 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4835 VDecl->setType(DclT); 4836 Init->setType(DclT); 4837 } 4838 4839 4840 // If this variable is a local declaration with record type, make sure it 4841 // doesn't have a flexible member initialization. We only support this as a 4842 // global/static definition. 4843 if (VDecl->hasLocalStorage()) 4844 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 4845 if (RT->getDecl()->hasFlexibleArrayMember()) { 4846 // Check whether the initializer tries to initialize the flexible 4847 // array member itself to anything other than an empty initializer list. 4848 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 4849 unsigned Index = std::distance(RT->getDecl()->field_begin(), 4850 RT->getDecl()->field_end()) - 1; 4851 if (Index < ILE->getNumInits() && 4852 !(isa<InitListExpr>(ILE->getInit(Index)) && 4853 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 4854 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 4855 VDecl->setInvalidDecl(); 4856 } 4857 } 4858 } 4859 4860 // Check any implicit conversions within the expression. 4861 CheckImplicitConversions(Init, VDecl->getLocation()); 4862 4863 Init = MaybeCreateExprWithCleanups(Init); 4864 // Attach the initializer to the decl. 4865 VDecl->setInit(Init); 4866 4867 CheckCompleteVariableDeclaration(VDecl); 4868} 4869 4870/// ActOnInitializerError - Given that there was an error parsing an 4871/// initializer for the given declaration, try to return to some form 4872/// of sanity. 4873void Sema::ActOnInitializerError(Decl *D) { 4874 // Our main concern here is re-establishing invariants like "a 4875 // variable's type is either dependent or complete". 4876 if (!D || D->isInvalidDecl()) return; 4877 4878 VarDecl *VD = dyn_cast<VarDecl>(D); 4879 if (!VD) return; 4880 4881 // Auto types are meaningless if we can't make sense of the initializer. 4882 if (ParsingInitForAutoVars.count(D)) { 4883 D->setInvalidDecl(); 4884 return; 4885 } 4886 4887 QualType Ty = VD->getType(); 4888 if (Ty->isDependentType()) return; 4889 4890 // Require a complete type. 4891 if (RequireCompleteType(VD->getLocation(), 4892 Context.getBaseElementType(Ty), 4893 diag::err_typecheck_decl_incomplete_type)) { 4894 VD->setInvalidDecl(); 4895 return; 4896 } 4897 4898 // Require an abstract type. 4899 if (RequireNonAbstractType(VD->getLocation(), Ty, 4900 diag::err_abstract_type_in_decl, 4901 AbstractVariableType)) { 4902 VD->setInvalidDecl(); 4903 return; 4904 } 4905 4906 // Don't bother complaining about constructors or destructors, 4907 // though. 4908} 4909 4910void Sema::ActOnUninitializedDecl(Decl *RealDecl, 4911 bool TypeMayContainAuto) { 4912 // If there is no declaration, there was an error parsing it. Just ignore it. 4913 if (RealDecl == 0) 4914 return; 4915 4916 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4917 QualType Type = Var->getType(); 4918 4919 // C++0x [dcl.spec.auto]p3 4920 if (TypeMayContainAuto && Type->getContainedAutoType()) { 4921 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4922 << Var->getDeclName() << Type; 4923 Var->setInvalidDecl(); 4924 return; 4925 } 4926 4927 switch (Var->isThisDeclarationADefinition()) { 4928 case VarDecl::Definition: 4929 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4930 break; 4931 4932 // We have an out-of-line definition of a static data member 4933 // that has an in-class initializer, so we type-check this like 4934 // a declaration. 4935 // 4936 // Fall through 4937 4938 case VarDecl::DeclarationOnly: 4939 // It's only a declaration. 4940 4941 // Block scope. C99 6.7p7: If an identifier for an object is 4942 // declared with no linkage (C99 6.2.2p6), the type for the 4943 // object shall be complete. 4944 if (!Type->isDependentType() && Var->isLocalVarDecl() && 4945 !Var->getLinkage() && !Var->isInvalidDecl() && 4946 RequireCompleteType(Var->getLocation(), Type, 4947 diag::err_typecheck_decl_incomplete_type)) 4948 Var->setInvalidDecl(); 4949 4950 // Make sure that the type is not abstract. 4951 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4952 RequireNonAbstractType(Var->getLocation(), Type, 4953 diag::err_abstract_type_in_decl, 4954 AbstractVariableType)) 4955 Var->setInvalidDecl(); 4956 return; 4957 4958 case VarDecl::TentativeDefinition: 4959 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4960 // object that has file scope without an initializer, and without a 4961 // storage-class specifier or with the storage-class specifier "static", 4962 // constitutes a tentative definition. Note: A tentative definition with 4963 // external linkage is valid (C99 6.2.2p5). 4964 if (!Var->isInvalidDecl()) { 4965 if (const IncompleteArrayType *ArrayT 4966 = Context.getAsIncompleteArrayType(Type)) { 4967 if (RequireCompleteType(Var->getLocation(), 4968 ArrayT->getElementType(), 4969 diag::err_illegal_decl_array_incomplete_type)) 4970 Var->setInvalidDecl(); 4971 } else if (Var->getStorageClass() == SC_Static) { 4972 // C99 6.9.2p3: If the declaration of an identifier for an object is 4973 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4974 // declared type shall not be an incomplete type. 4975 // NOTE: code such as the following 4976 // static struct s; 4977 // struct s { int a; }; 4978 // is accepted by gcc. Hence here we issue a warning instead of 4979 // an error and we do not invalidate the static declaration. 4980 // NOTE: to avoid multiple warnings, only check the first declaration. 4981 if (Var->getPreviousDeclaration() == 0) 4982 RequireCompleteType(Var->getLocation(), Type, 4983 diag::ext_typecheck_decl_incomplete_type); 4984 } 4985 } 4986 4987 // Record the tentative definition; we're done. 4988 if (!Var->isInvalidDecl()) 4989 TentativeDefinitions.push_back(Var); 4990 return; 4991 } 4992 4993 // Provide a specific diagnostic for uninitialized variable 4994 // definitions with incomplete array type. 4995 if (Type->isIncompleteArrayType()) { 4996 Diag(Var->getLocation(), 4997 diag::err_typecheck_incomplete_array_needs_initializer); 4998 Var->setInvalidDecl(); 4999 return; 5000 } 5001 5002 // Provide a specific diagnostic for uninitialized variable 5003 // definitions with reference type. 5004 if (Type->isReferenceType()) { 5005 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5006 << Var->getDeclName() 5007 << SourceRange(Var->getLocation(), Var->getLocation()); 5008 Var->setInvalidDecl(); 5009 return; 5010 } 5011 5012 // Do not attempt to type-check the default initializer for a 5013 // variable with dependent type. 5014 if (Type->isDependentType()) 5015 return; 5016 5017 if (Var->isInvalidDecl()) 5018 return; 5019 5020 if (RequireCompleteType(Var->getLocation(), 5021 Context.getBaseElementType(Type), 5022 diag::err_typecheck_decl_incomplete_type)) { 5023 Var->setInvalidDecl(); 5024 return; 5025 } 5026 5027 // The variable can not have an abstract class type. 5028 if (RequireNonAbstractType(Var->getLocation(), Type, 5029 diag::err_abstract_type_in_decl, 5030 AbstractVariableType)) { 5031 Var->setInvalidDecl(); 5032 return; 5033 } 5034 5035 const RecordType *Record 5036 = Context.getBaseElementType(Type)->getAs<RecordType>(); 5037 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 5038 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 5039 // C++03 [dcl.init]p9: 5040 // If no initializer is specified for an object, and the 5041 // object is of (possibly cv-qualified) non-POD class type (or 5042 // array thereof), the object shall be default-initialized; if 5043 // the object is of const-qualified type, the underlying class 5044 // type shall have a user-declared default 5045 // constructor. Otherwise, if no initializer is specified for 5046 // a non- static object, the object and its subobjects, if 5047 // any, have an indeterminate initial value); if the object 5048 // or any of its subobjects are of const-qualified type, the 5049 // program is ill-formed. 5050 // FIXME: DPG thinks it is very fishy that C++0x disables this. 5051 } else { 5052 // Check for jumps past the implicit initializer. C++0x 5053 // clarifies that this applies to a "variable with automatic 5054 // storage duration", not a "local variable". 5055 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 5056 getCurFunction()->setHasBranchProtectedScope(); 5057 5058 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5059 InitializationKind Kind 5060 = InitializationKind::CreateDefault(Var->getLocation()); 5061 5062 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5063 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5064 MultiExprArg(*this, 0, 0)); 5065 if (Init.isInvalid()) 5066 Var->setInvalidDecl(); 5067 else if (Init.get()) 5068 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5069 } 5070 5071 CheckCompleteVariableDeclaration(Var); 5072 } 5073} 5074 5075void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5076 if (var->isInvalidDecl()) return; 5077 5078 // All the following checks are C++ only. 5079 if (!getLangOptions().CPlusPlus) return; 5080 5081 QualType baseType = Context.getBaseElementType(var->getType()); 5082 if (baseType->isDependentType()) return; 5083 5084 // __block variables might require us to capture a copy-initializer. 5085 if (var->hasAttr<BlocksAttr>()) { 5086 // It's currently invalid to ever have a __block variable with an 5087 // array type; should we diagnose that here? 5088 5089 // Regardless, we don't want to ignore array nesting when 5090 // constructing this copy. 5091 QualType type = var->getType(); 5092 5093 if (type->isStructureOrClassType()) { 5094 SourceLocation poi = var->getLocation(); 5095 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5096 ExprResult result = 5097 PerformCopyInitialization( 5098 InitializedEntity::InitializeBlock(poi, type, false), 5099 poi, Owned(varRef)); 5100 if (!result.isInvalid()) { 5101 result = MaybeCreateExprWithCleanups(result); 5102 Expr *init = result.takeAs<Expr>(); 5103 Context.setBlockVarCopyInits(var, init); 5104 } 5105 } 5106 } 5107 5108 // Check for global constructors. 5109 if (!var->getDeclContext()->isDependentContext() && 5110 var->hasGlobalStorage() && 5111 !var->isStaticLocal() && 5112 var->getInit() && 5113 !var->getInit()->isConstantInitializer(Context, 5114 baseType->isReferenceType())) 5115 Diag(var->getLocation(), diag::warn_global_constructor) 5116 << var->getInit()->getSourceRange(); 5117 5118 // Require the destructor. 5119 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5120 FinalizeVarWithDestructor(var, recordType); 5121} 5122 5123/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5124/// any semantic actions necessary after any initializer has been attached. 5125void 5126Sema::FinalizeDeclaration(Decl *ThisDecl) { 5127 // Note that we are no longer parsing the initializer for this declaration. 5128 ParsingInitForAutoVars.erase(ThisDecl); 5129} 5130 5131Sema::DeclGroupPtrTy 5132Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5133 Decl **Group, unsigned NumDecls) { 5134 llvm::SmallVector<Decl*, 8> Decls; 5135 5136 if (DS.isTypeSpecOwned()) 5137 Decls.push_back(DS.getRepAsDecl()); 5138 5139 for (unsigned i = 0; i != NumDecls; ++i) 5140 if (Decl *D = Group[i]) 5141 Decls.push_back(D); 5142 5143 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5144 DS.getTypeSpecType() == DeclSpec::TST_auto); 5145} 5146 5147/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5148/// group, performing any necessary semantic checking. 5149Sema::DeclGroupPtrTy 5150Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5151 bool TypeMayContainAuto) { 5152 // C++0x [dcl.spec.auto]p7: 5153 // If the type deduced for the template parameter U is not the same in each 5154 // deduction, the program is ill-formed. 5155 // FIXME: When initializer-list support is added, a distinction is needed 5156 // between the deduced type U and the deduced type which 'auto' stands for. 5157 // auto a = 0, b = { 1, 2, 3 }; 5158 // is legal because the deduced type U is 'int' in both cases. 5159 if (TypeMayContainAuto && NumDecls > 1) { 5160 QualType Deduced; 5161 CanQualType DeducedCanon; 5162 VarDecl *DeducedDecl = 0; 5163 for (unsigned i = 0; i != NumDecls; ++i) { 5164 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5165 AutoType *AT = D->getType()->getContainedAutoType(); 5166 // Don't reissue diagnostics when instantiating a template. 5167 if (AT && D->isInvalidDecl()) 5168 break; 5169 if (AT && AT->isDeduced()) { 5170 QualType U = AT->getDeducedType(); 5171 CanQualType UCanon = Context.getCanonicalType(U); 5172 if (Deduced.isNull()) { 5173 Deduced = U; 5174 DeducedCanon = UCanon; 5175 DeducedDecl = D; 5176 } else if (DeducedCanon != UCanon) { 5177 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5178 diag::err_auto_different_deductions) 5179 << Deduced << DeducedDecl->getDeclName() 5180 << U << D->getDeclName() 5181 << DeducedDecl->getInit()->getSourceRange() 5182 << D->getInit()->getSourceRange(); 5183 D->setInvalidDecl(); 5184 break; 5185 } 5186 } 5187 } 5188 } 5189 } 5190 5191 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5192} 5193 5194 5195/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5196/// to introduce parameters into function prototype scope. 5197Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5198 const DeclSpec &DS = D.getDeclSpec(); 5199 5200 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5201 VarDecl::StorageClass StorageClass = SC_None; 5202 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5203 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5204 StorageClass = SC_Register; 5205 StorageClassAsWritten = SC_Register; 5206 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5207 Diag(DS.getStorageClassSpecLoc(), 5208 diag::err_invalid_storage_class_in_func_decl); 5209 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5210 } 5211 5212 if (D.getDeclSpec().isThreadSpecified()) 5213 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5214 5215 DiagnoseFunctionSpecifiers(D); 5216 5217 TagDecl *OwnedDecl = 0; 5218 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 5219 QualType parmDeclType = TInfo->getType(); 5220 5221 if (getLangOptions().CPlusPlus) { 5222 // Check that there are no default arguments inside the type of this 5223 // parameter. 5224 CheckExtraCXXDefaultArguments(D); 5225 5226 if (OwnedDecl && OwnedDecl->isDefinition()) { 5227 // C++ [dcl.fct]p6: 5228 // Types shall not be defined in return or parameter types. 5229 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 5230 << Context.getTypeDeclType(OwnedDecl); 5231 } 5232 5233 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5234 if (D.getCXXScopeSpec().isSet()) { 5235 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5236 << D.getCXXScopeSpec().getRange(); 5237 D.getCXXScopeSpec().clear(); 5238 } 5239 } 5240 5241 // Ensure we have a valid name 5242 IdentifierInfo *II = 0; 5243 if (D.hasName()) { 5244 II = D.getIdentifier(); 5245 if (!II) { 5246 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5247 << GetNameForDeclarator(D).getName().getAsString(); 5248 D.setInvalidType(true); 5249 } 5250 } 5251 5252 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 5253 if (II) { 5254 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 5255 ForRedeclaration); 5256 LookupName(R, S); 5257 if (R.isSingleResult()) { 5258 NamedDecl *PrevDecl = R.getFoundDecl(); 5259 if (PrevDecl->isTemplateParameter()) { 5260 // Maybe we will complain about the shadowed template parameter. 5261 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5262 // Just pretend that we didn't see the previous declaration. 5263 PrevDecl = 0; 5264 } else if (S->isDeclScope(PrevDecl)) { 5265 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 5266 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5267 5268 // Recover by removing the name 5269 II = 0; 5270 D.SetIdentifier(0, D.getIdentifierLoc()); 5271 D.setInvalidType(true); 5272 } 5273 } 5274 } 5275 5276 // Temporarily put parameter variables in the translation unit, not 5277 // the enclosing context. This prevents them from accidentally 5278 // looking like class members in C++. 5279 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 5280 TInfo, parmDeclType, II, 5281 D.getIdentifierLoc(), 5282 StorageClass, StorageClassAsWritten); 5283 5284 if (D.isInvalidType()) 5285 New->setInvalidDecl(); 5286 5287 // Add the parameter declaration into this scope. 5288 S->AddDecl(New); 5289 if (II) 5290 IdResolver.AddDecl(New); 5291 5292 ProcessDeclAttributes(S, New, D); 5293 5294 if (New->hasAttr<BlocksAttr>()) { 5295 Diag(New->getLocation(), diag::err_block_on_nonlocal); 5296 } 5297 return New; 5298} 5299 5300/// \brief Synthesizes a variable for a parameter arising from a 5301/// typedef. 5302ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 5303 SourceLocation Loc, 5304 QualType T) { 5305 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 5306 T, Context.getTrivialTypeSourceInfo(T, Loc), 5307 SC_None, SC_None, 0); 5308 Param->setImplicit(); 5309 return Param; 5310} 5311 5312void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 5313 ParmVarDecl * const *ParamEnd) { 5314 // Don't diagnose unused-parameter errors in template instantiations; we 5315 // will already have done so in the template itself. 5316 if (!ActiveTemplateInstantiations.empty()) 5317 return; 5318 5319 for (; Param != ParamEnd; ++Param) { 5320 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 5321 !(*Param)->hasAttr<UnusedAttr>()) { 5322 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 5323 << (*Param)->getDeclName(); 5324 } 5325 } 5326} 5327 5328void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 5329 ParmVarDecl * const *ParamEnd, 5330 QualType ReturnTy, 5331 NamedDecl *D) { 5332 if (LangOpts.NumLargeByValueCopy == 0) // No check. 5333 return; 5334 5335 // Warn if the return value is pass-by-value and larger than the specified 5336 // threshold. 5337 if (ReturnTy->isPODType()) { 5338 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 5339 if (Size > LangOpts.NumLargeByValueCopy) 5340 Diag(D->getLocation(), diag::warn_return_value_size) 5341 << D->getDeclName() << Size; 5342 } 5343 5344 // Warn if any parameter is pass-by-value and larger than the specified 5345 // threshold. 5346 for (; Param != ParamEnd; ++Param) { 5347 QualType T = (*Param)->getType(); 5348 if (!T->isPODType()) 5349 continue; 5350 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 5351 if (Size > LangOpts.NumLargeByValueCopy) 5352 Diag((*Param)->getLocation(), diag::warn_parameter_size) 5353 << (*Param)->getDeclName() << Size; 5354 } 5355} 5356 5357ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 5358 TypeSourceInfo *TSInfo, QualType T, 5359 IdentifierInfo *Name, 5360 SourceLocation NameLoc, 5361 VarDecl::StorageClass StorageClass, 5362 VarDecl::StorageClass StorageClassAsWritten) { 5363 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 5364 adjustParameterType(T), TSInfo, 5365 StorageClass, StorageClassAsWritten, 5366 0); 5367 5368 // Parameters can not be abstract class types. 5369 // For record types, this is done by the AbstractClassUsageDiagnoser once 5370 // the class has been completely parsed. 5371 if (!CurContext->isRecord() && 5372 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 5373 AbstractParamType)) 5374 New->setInvalidDecl(); 5375 5376 // Parameter declarators cannot be interface types. All ObjC objects are 5377 // passed by reference. 5378 if (T->isObjCObjectType()) { 5379 Diag(NameLoc, 5380 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 5381 New->setInvalidDecl(); 5382 } 5383 5384 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 5385 // duration shall not be qualified by an address-space qualifier." 5386 // Since all parameters have automatic store duration, they can not have 5387 // an address space. 5388 if (T.getAddressSpace() != 0) { 5389 Diag(NameLoc, diag::err_arg_with_address_space); 5390 New->setInvalidDecl(); 5391 } 5392 5393 return New; 5394} 5395 5396void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 5397 SourceLocation LocAfterDecls) { 5398 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 5399 5400 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 5401 // for a K&R function. 5402 if (!FTI.hasPrototype) { 5403 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 5404 --i; 5405 if (FTI.ArgInfo[i].Param == 0) { 5406 llvm::SmallString<256> Code; 5407 llvm::raw_svector_ostream(Code) << " int " 5408 << FTI.ArgInfo[i].Ident->getName() 5409 << ";\n"; 5410 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 5411 << FTI.ArgInfo[i].Ident 5412 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 5413 5414 // Implicitly declare the argument as type 'int' for lack of a better 5415 // type. 5416 DeclSpec DS; 5417 const char* PrevSpec; // unused 5418 unsigned DiagID; // unused 5419 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 5420 PrevSpec, DiagID); 5421 Declarator ParamD(DS, Declarator::KNRTypeListContext); 5422 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 5423 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 5424 } 5425 } 5426 } 5427} 5428 5429Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 5430 Declarator &D) { 5431 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 5432 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 5433 Scope *ParentScope = FnBodyScope->getParent(); 5434 5435 Decl *DP = HandleDeclarator(ParentScope, D, 5436 MultiTemplateParamsArg(*this), 5437 /*IsFunctionDefinition=*/true); 5438 return ActOnStartOfFunctionDef(FnBodyScope, DP); 5439} 5440 5441static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 5442 // Don't warn about invalid declarations. 5443 if (FD->isInvalidDecl()) 5444 return false; 5445 5446 // Or declarations that aren't global. 5447 if (!FD->isGlobal()) 5448 return false; 5449 5450 // Don't warn about C++ member functions. 5451 if (isa<CXXMethodDecl>(FD)) 5452 return false; 5453 5454 // Don't warn about 'main'. 5455 if (FD->isMain()) 5456 return false; 5457 5458 // Don't warn about inline functions. 5459 if (FD->isInlineSpecified()) 5460 return false; 5461 5462 // Don't warn about function templates. 5463 if (FD->getDescribedFunctionTemplate()) 5464 return false; 5465 5466 // Don't warn about function template specializations. 5467 if (FD->isFunctionTemplateSpecialization()) 5468 return false; 5469 5470 bool MissingPrototype = true; 5471 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 5472 Prev; Prev = Prev->getPreviousDeclaration()) { 5473 // Ignore any declarations that occur in function or method 5474 // scope, because they aren't visible from the header. 5475 if (Prev->getDeclContext()->isFunctionOrMethod()) 5476 continue; 5477 5478 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 5479 break; 5480 } 5481 5482 return MissingPrototype; 5483} 5484 5485Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 5486 // Clear the last template instantiation error context. 5487 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 5488 5489 if (!D) 5490 return D; 5491 FunctionDecl *FD = 0; 5492 5493 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 5494 FD = FunTmpl->getTemplatedDecl(); 5495 else 5496 FD = cast<FunctionDecl>(D); 5497 5498 // Enter a new function scope 5499 PushFunctionScope(); 5500 5501 // See if this is a redefinition. 5502 // But don't complain if we're in GNU89 mode and the previous definition 5503 // was an extern inline function. 5504 const FunctionDecl *Definition; 5505 if (FD->hasBody(Definition) && 5506 !canRedefineFunction(Definition, getLangOptions())) { 5507 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 5508 Definition->getStorageClass() == SC_Extern) 5509 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 5510 << FD->getDeclName() << getLangOptions().CPlusPlus; 5511 else 5512 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 5513 Diag(Definition->getLocation(), diag::note_previous_definition); 5514 } 5515 5516 // Builtin functions cannot be defined. 5517 if (unsigned BuiltinID = FD->getBuiltinID()) { 5518 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 5519 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 5520 FD->setInvalidDecl(); 5521 } 5522 } 5523 5524 // The return type of a function definition must be complete 5525 // (C99 6.9.1p3, C++ [dcl.fct]p6). 5526 QualType ResultType = FD->getResultType(); 5527 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 5528 !FD->isInvalidDecl() && 5529 RequireCompleteType(FD->getLocation(), ResultType, 5530 diag::err_func_def_incomplete_result)) 5531 FD->setInvalidDecl(); 5532 5533 // GNU warning -Wmissing-prototypes: 5534 // Warn if a global function is defined without a previous 5535 // prototype declaration. This warning is issued even if the 5536 // definition itself provides a prototype. The aim is to detect 5537 // global functions that fail to be declared in header files. 5538 if (ShouldWarnAboutMissingPrototype(FD)) 5539 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 5540 5541 if (FnBodyScope) 5542 PushDeclContext(FnBodyScope, FD); 5543 5544 // Check the validity of our function parameters 5545 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 5546 /*CheckParameterNames=*/true); 5547 5548 // Introduce our parameters into the function scope 5549 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 5550 ParmVarDecl *Param = FD->getParamDecl(p); 5551 Param->setOwningFunction(FD); 5552 5553 // If this has an identifier, add it to the scope stack. 5554 if (Param->getIdentifier() && FnBodyScope) { 5555 CheckShadow(FnBodyScope, Param); 5556 5557 PushOnScopeChains(Param, FnBodyScope); 5558 } 5559 } 5560 5561 // Checking attributes of current function definition 5562 // dllimport attribute. 5563 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5564 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5565 // dllimport attribute cannot be directly applied to definition. 5566 if (!DA->isInherited()) { 5567 Diag(FD->getLocation(), 5568 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5569 << "dllimport"; 5570 FD->setInvalidDecl(); 5571 return FD; 5572 } 5573 5574 // Visual C++ appears to not think this is an issue, so only issue 5575 // a warning when Microsoft extensions are disabled. 5576 if (!LangOpts.Microsoft) { 5577 // If a symbol previously declared dllimport is later defined, the 5578 // attribute is ignored in subsequent references, and a warning is 5579 // emitted. 5580 Diag(FD->getLocation(), 5581 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5582 << FD->getName() << "dllimport"; 5583 } 5584 } 5585 return FD; 5586} 5587 5588/// \brief Given the set of return statements within a function body, 5589/// compute the variables that are subject to the named return value 5590/// optimization. 5591/// 5592/// Each of the variables that is subject to the named return value 5593/// optimization will be marked as NRVO variables in the AST, and any 5594/// return statement that has a marked NRVO variable as its NRVO candidate can 5595/// use the named return value optimization. 5596/// 5597/// This function applies a very simplistic algorithm for NRVO: if every return 5598/// statement in the function has the same NRVO candidate, that candidate is 5599/// the NRVO variable. 5600/// 5601/// FIXME: Employ a smarter algorithm that accounts for multiple return 5602/// statements and the lifetimes of the NRVO candidates. We should be able to 5603/// find a maximal set of NRVO variables. 5604static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5605 ReturnStmt **Returns = Scope->Returns.data(); 5606 5607 const VarDecl *NRVOCandidate = 0; 5608 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5609 if (!Returns[I]->getNRVOCandidate()) 5610 return; 5611 5612 if (!NRVOCandidate) 5613 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5614 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5615 return; 5616 } 5617 5618 if (NRVOCandidate) 5619 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5620} 5621 5622Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5623 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5624} 5625 5626Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5627 bool IsInstantiation) { 5628 FunctionDecl *FD = 0; 5629 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5630 if (FunTmpl) 5631 FD = FunTmpl->getTemplatedDecl(); 5632 else 5633 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5634 5635 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5636 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 5637 5638 if (FD) { 5639 FD->setBody(Body); 5640 if (FD->isMain()) { 5641 // C and C++ allow for main to automagically return 0. 5642 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5643 FD->setHasImplicitReturnZero(true); 5644 WP.disableCheckFallThrough(); 5645 } 5646 5647 if (!FD->isInvalidDecl()) { 5648 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5649 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 5650 FD->getResultType(), FD); 5651 5652 // If this is a constructor, we need a vtable. 5653 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5654 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5655 5656 ComputeNRVO(Body, getCurFunction()); 5657 } 5658 5659 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5660 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5661 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5662 MD->setBody(Body); 5663 if (Body) 5664 MD->setEndLoc(Body->getLocEnd()); 5665 if (!MD->isInvalidDecl()) { 5666 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5667 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 5668 MD->getResultType(), MD); 5669 } 5670 } else { 5671 return 0; 5672 } 5673 5674 // Verify and clean out per-function state. 5675 if (Body) { 5676 // C++ constructors that have function-try-blocks can't have return 5677 // statements in the handlers of that block. (C++ [except.handle]p14) 5678 // Verify this. 5679 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5680 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5681 5682 // Verify that that gotos and switch cases don't jump into scopes illegally. 5683 // Verify that that gotos and switch cases don't jump into scopes illegally. 5684 if (getCurFunction()->NeedsScopeChecking() && 5685 !dcl->isInvalidDecl() && 5686 !hasAnyErrorsInThisFunction()) 5687 DiagnoseInvalidJumps(Body); 5688 5689 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5690 if (!Destructor->getParent()->isDependentType()) 5691 CheckDestructor(Destructor); 5692 5693 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5694 Destructor->getParent()); 5695 } 5696 5697 // If any errors have occurred, clear out any temporaries that may have 5698 // been leftover. This ensures that these temporaries won't be picked up for 5699 // deletion in some later function. 5700 if (PP.getDiagnostics().hasErrorOccurred()) 5701 ExprTemporaries.clear(); 5702 else if (!isa<FunctionTemplateDecl>(dcl)) { 5703 // Since the body is valid, issue any analysis-based warnings that are 5704 // enabled. 5705 ActivePolicy = &WP; 5706 } 5707 5708 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5709 } 5710 5711 if (!IsInstantiation) 5712 PopDeclContext(); 5713 5714 PopFunctionOrBlockScope(ActivePolicy, dcl); 5715 5716 // If any errors have occurred, clear out any temporaries that may have 5717 // been leftover. This ensures that these temporaries won't be picked up for 5718 // deletion in some later function. 5719 if (getDiagnostics().hasErrorOccurred()) 5720 ExprTemporaries.clear(); 5721 5722 return dcl; 5723} 5724 5725/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5726/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5727NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5728 IdentifierInfo &II, Scope *S) { 5729 // Before we produce a declaration for an implicitly defined 5730 // function, see whether there was a locally-scoped declaration of 5731 // this name as a function or variable. If so, use that 5732 // (non-visible) declaration, and complain about it. 5733 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5734 = LocallyScopedExternalDecls.find(&II); 5735 if (Pos != LocallyScopedExternalDecls.end()) { 5736 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5737 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5738 return Pos->second; 5739 } 5740 5741 // Extension in C99. Legal in C90, but warn about it. 5742 if (II.getName().startswith("__builtin_")) 5743 Diag(Loc, diag::warn_builtin_unknown) << &II; 5744 else if (getLangOptions().C99) 5745 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5746 else 5747 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5748 5749 // Set a Declarator for the implicit definition: int foo(); 5750 const char *Dummy; 5751 DeclSpec DS; 5752 unsigned DiagID; 5753 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5754 (void)Error; // Silence warning. 5755 assert(!Error && "Error setting up implicit decl!"); 5756 Declarator D(DS, Declarator::BlockContext); 5757 D.AddTypeInfo(DeclaratorChunk::getFunction(ParsedAttributes(), 5758 false, false, SourceLocation(), 0, 5759 0, 0, true, SourceLocation(), 5760 false, SourceLocation(), 5761 false, 0,0,0, Loc, Loc, D), 5762 SourceLocation()); 5763 D.SetIdentifier(&II, Loc); 5764 5765 // Insert this function into translation-unit scope. 5766 5767 DeclContext *PrevDC = CurContext; 5768 CurContext = Context.getTranslationUnitDecl(); 5769 5770 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5771 FD->setImplicit(); 5772 5773 CurContext = PrevDC; 5774 5775 AddKnownFunctionAttributes(FD); 5776 5777 return FD; 5778} 5779 5780/// \brief Adds any function attributes that we know a priori based on 5781/// the declaration of this function. 5782/// 5783/// These attributes can apply both to implicitly-declared builtins 5784/// (like __builtin___printf_chk) or to library-declared functions 5785/// like NSLog or printf. 5786void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5787 if (FD->isInvalidDecl()) 5788 return; 5789 5790 // If this is a built-in function, map its builtin attributes to 5791 // actual attributes. 5792 if (unsigned BuiltinID = FD->getBuiltinID()) { 5793 // Handle printf-formatting attributes. 5794 unsigned FormatIdx; 5795 bool HasVAListArg; 5796 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5797 if (!FD->getAttr<FormatAttr>()) 5798 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5799 "printf", FormatIdx+1, 5800 HasVAListArg ? 0 : FormatIdx+2)); 5801 } 5802 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5803 HasVAListArg)) { 5804 if (!FD->getAttr<FormatAttr>()) 5805 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5806 "scanf", FormatIdx+1, 5807 HasVAListArg ? 0 : FormatIdx+2)); 5808 } 5809 5810 // Mark const if we don't care about errno and that is the only 5811 // thing preventing the function from being const. This allows 5812 // IRgen to use LLVM intrinsics for such functions. 5813 if (!getLangOptions().MathErrno && 5814 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5815 if (!FD->getAttr<ConstAttr>()) 5816 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5817 } 5818 5819 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5820 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 5821 if (Context.BuiltinInfo.isConst(BuiltinID)) 5822 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 5823 } 5824 5825 IdentifierInfo *Name = FD->getIdentifier(); 5826 if (!Name) 5827 return; 5828 if ((!getLangOptions().CPlusPlus && 5829 FD->getDeclContext()->isTranslationUnit()) || 5830 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5831 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5832 LinkageSpecDecl::lang_c)) { 5833 // Okay: this could be a libc/libm/Objective-C function we know 5834 // about. 5835 } else 5836 return; 5837 5838 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5839 // FIXME: NSLog and NSLogv should be target specific 5840 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5841 // FIXME: We known better than our headers. 5842 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5843 } else 5844 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5845 "printf", 1, 5846 Name->isStr("NSLogv") ? 0 : 2)); 5847 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5848 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5849 // target-specific builtins, perhaps? 5850 if (!FD->getAttr<FormatAttr>()) 5851 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5852 "printf", 2, 5853 Name->isStr("vasprintf") ? 0 : 3)); 5854 } 5855} 5856 5857TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5858 TypeSourceInfo *TInfo) { 5859 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5860 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5861 5862 if (!TInfo) { 5863 assert(D.isInvalidType() && "no declarator info for valid type"); 5864 TInfo = Context.getTrivialTypeSourceInfo(T); 5865 } 5866 5867 // Scope manipulation handled by caller. 5868 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5869 D.getIdentifierLoc(), 5870 D.getIdentifier(), 5871 TInfo); 5872 5873 // Bail out immediately if we have an invalid declaration. 5874 if (D.isInvalidType()) { 5875 NewTD->setInvalidDecl(); 5876 return NewTD; 5877 } 5878 5879 // C++ [dcl.typedef]p8: 5880 // If the typedef declaration defines an unnamed class (or 5881 // enum), the first typedef-name declared by the declaration 5882 // to be that class type (or enum type) is used to denote the 5883 // class type (or enum type) for linkage purposes only. 5884 // We need to check whether the type was declared in the declaration. 5885 switch (D.getDeclSpec().getTypeSpecType()) { 5886 case TST_enum: 5887 case TST_struct: 5888 case TST_union: 5889 case TST_class: { 5890 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 5891 5892 // Do nothing if the tag is not anonymous or already has an 5893 // associated typedef (from an earlier typedef in this decl group). 5894 if (tagFromDeclSpec->getIdentifier()) break; 5895 if (tagFromDeclSpec->getTypedefForAnonDecl()) break; 5896 5897 // A well-formed anonymous tag must always be a TUK_Definition. 5898 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 5899 5900 // The type must match the tag exactly; no qualifiers allowed. 5901 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 5902 break; 5903 5904 // Otherwise, set this is the anon-decl typedef for the tag. 5905 tagFromDeclSpec->setTypedefForAnonDecl(NewTD); 5906 break; 5907 } 5908 5909 default: 5910 break; 5911 } 5912 5913 return NewTD; 5914} 5915 5916 5917/// \brief Determine whether a tag with a given kind is acceptable 5918/// as a redeclaration of the given tag declaration. 5919/// 5920/// \returns true if the new tag kind is acceptable, false otherwise. 5921bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5922 TagTypeKind NewTag, 5923 SourceLocation NewTagLoc, 5924 const IdentifierInfo &Name) { 5925 // C++ [dcl.type.elab]p3: 5926 // The class-key or enum keyword present in the 5927 // elaborated-type-specifier shall agree in kind with the 5928 // declaration to which the name in the elaborated-type-specifier 5929 // refers. This rule also applies to the form of 5930 // elaborated-type-specifier that declares a class-name or 5931 // friend class since it can be construed as referring to the 5932 // definition of the class. Thus, in any 5933 // elaborated-type-specifier, the enum keyword shall be used to 5934 // refer to an enumeration (7.2), the union class-key shall be 5935 // used to refer to a union (clause 9), and either the class or 5936 // struct class-key shall be used to refer to a class (clause 9) 5937 // declared using the class or struct class-key. 5938 TagTypeKind OldTag = Previous->getTagKind(); 5939 if (OldTag == NewTag) 5940 return true; 5941 5942 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5943 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5944 // Warn about the struct/class tag mismatch. 5945 bool isTemplate = false; 5946 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5947 isTemplate = Record->getDescribedClassTemplate(); 5948 5949 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5950 << (NewTag == TTK_Class) 5951 << isTemplate << &Name 5952 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5953 OldTag == TTK_Class? "class" : "struct"); 5954 Diag(Previous->getLocation(), diag::note_previous_use); 5955 return true; 5956 } 5957 return false; 5958} 5959 5960/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5961/// former case, Name will be non-null. In the later case, Name will be null. 5962/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5963/// reference/declaration/definition of a tag. 5964Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5965 SourceLocation KWLoc, CXXScopeSpec &SS, 5966 IdentifierInfo *Name, SourceLocation NameLoc, 5967 AttributeList *Attr, AccessSpecifier AS, 5968 MultiTemplateParamsArg TemplateParameterLists, 5969 bool &OwnedDecl, bool &IsDependent, 5970 bool ScopedEnum, bool ScopedEnumUsesClassTag, 5971 TypeResult UnderlyingType) { 5972 // If this is not a definition, it must have a name. 5973 assert((Name != 0 || TUK == TUK_Definition) && 5974 "Nameless record must be a definition!"); 5975 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 5976 5977 OwnedDecl = false; 5978 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5979 5980 // FIXME: Check explicit specializations more carefully. 5981 bool isExplicitSpecialization = false; 5982 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5983 bool Invalid = false; 5984 5985 // We only need to do this matching if we have template parameters 5986 // or a scope specifier, which also conveniently avoids this work 5987 // for non-C++ cases. 5988 if (NumMatchedTemplateParamLists || 5989 (SS.isNotEmpty() && TUK != TUK_Reference)) { 5990 if (TemplateParameterList *TemplateParams 5991 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5992 TemplateParameterLists.get(), 5993 TemplateParameterLists.size(), 5994 TUK == TUK_Friend, 5995 isExplicitSpecialization, 5996 Invalid)) { 5997 // All but one template parameter lists have been matching. 5998 --NumMatchedTemplateParamLists; 5999 6000 if (TemplateParams->size() > 0) { 6001 // This is a declaration or definition of a class template (which may 6002 // be a member of another template). 6003 if (Invalid) 6004 return 0; 6005 6006 OwnedDecl = false; 6007 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6008 SS, Name, NameLoc, Attr, 6009 TemplateParams, 6010 AS); 6011 TemplateParameterLists.release(); 6012 return Result.get(); 6013 } else { 6014 // The "template<>" header is extraneous. 6015 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6016 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6017 isExplicitSpecialization = true; 6018 } 6019 } 6020 } 6021 6022 // Figure out the underlying type if this a enum declaration. We need to do 6023 // this early, because it's needed to detect if this is an incompatible 6024 // redeclaration. 6025 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6026 6027 if (Kind == TTK_Enum) { 6028 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6029 // No underlying type explicitly specified, or we failed to parse the 6030 // type, default to int. 6031 EnumUnderlying = Context.IntTy.getTypePtr(); 6032 else if (UnderlyingType.get()) { 6033 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6034 // integral type; any cv-qualification is ignored. 6035 TypeSourceInfo *TI = 0; 6036 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6037 EnumUnderlying = TI; 6038 6039 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6040 6041 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6042 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6043 << T; 6044 // Recover by falling back to int. 6045 EnumUnderlying = Context.IntTy.getTypePtr(); 6046 } 6047 6048 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6049 UPPC_FixedUnderlyingType)) 6050 EnumUnderlying = Context.IntTy.getTypePtr(); 6051 6052 } else if (getLangOptions().Microsoft) 6053 // Microsoft enums are always of int type. 6054 EnumUnderlying = Context.IntTy.getTypePtr(); 6055 } 6056 6057 DeclContext *SearchDC = CurContext; 6058 DeclContext *DC = CurContext; 6059 bool isStdBadAlloc = false; 6060 6061 RedeclarationKind Redecl = ForRedeclaration; 6062 if (TUK == TUK_Friend || TUK == TUK_Reference) 6063 Redecl = NotForRedeclaration; 6064 6065 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6066 6067 if (Name && SS.isNotEmpty()) { 6068 // We have a nested-name tag ('struct foo::bar'). 6069 6070 // Check for invalid 'foo::'. 6071 if (SS.isInvalid()) { 6072 Name = 0; 6073 goto CreateNewDecl; 6074 } 6075 6076 // If this is a friend or a reference to a class in a dependent 6077 // context, don't try to make a decl for it. 6078 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6079 DC = computeDeclContext(SS, false); 6080 if (!DC) { 6081 IsDependent = true; 6082 return 0; 6083 } 6084 } else { 6085 DC = computeDeclContext(SS, true); 6086 if (!DC) { 6087 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6088 << SS.getRange(); 6089 return 0; 6090 } 6091 } 6092 6093 if (RequireCompleteDeclContext(SS, DC)) 6094 return 0; 6095 6096 SearchDC = DC; 6097 // Look-up name inside 'foo::'. 6098 LookupQualifiedName(Previous, DC); 6099 6100 if (Previous.isAmbiguous()) 6101 return 0; 6102 6103 if (Previous.empty()) { 6104 // Name lookup did not find anything. However, if the 6105 // nested-name-specifier refers to the current instantiation, 6106 // and that current instantiation has any dependent base 6107 // classes, we might find something at instantiation time: treat 6108 // this as a dependent elaborated-type-specifier. 6109 // But this only makes any sense for reference-like lookups. 6110 if (Previous.wasNotFoundInCurrentInstantiation() && 6111 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6112 IsDependent = true; 6113 return 0; 6114 } 6115 6116 // A tag 'foo::bar' must already exist. 6117 Diag(NameLoc, diag::err_not_tag_in_scope) 6118 << Kind << Name << DC << SS.getRange(); 6119 Name = 0; 6120 Invalid = true; 6121 goto CreateNewDecl; 6122 } 6123 } else if (Name) { 6124 // If this is a named struct, check to see if there was a previous forward 6125 // declaration or definition. 6126 // FIXME: We're looking into outer scopes here, even when we 6127 // shouldn't be. Doing so can result in ambiguities that we 6128 // shouldn't be diagnosing. 6129 LookupName(Previous, S); 6130 6131 // Note: there used to be some attempt at recovery here. 6132 if (Previous.isAmbiguous()) 6133 return 0; 6134 6135 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6136 // FIXME: This makes sure that we ignore the contexts associated 6137 // with C structs, unions, and enums when looking for a matching 6138 // tag declaration or definition. See the similar lookup tweak 6139 // in Sema::LookupName; is there a better way to deal with this? 6140 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 6141 SearchDC = SearchDC->getParent(); 6142 } 6143 } else if (S->isFunctionPrototypeScope()) { 6144 // If this is an enum declaration in function prototype scope, set its 6145 // initial context to the translation unit. 6146 SearchDC = Context.getTranslationUnitDecl(); 6147 } 6148 6149 if (Previous.isSingleResult() && 6150 Previous.getFoundDecl()->isTemplateParameter()) { 6151 // Maybe we will complain about the shadowed template parameter. 6152 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 6153 // Just pretend that we didn't see the previous declaration. 6154 Previous.clear(); 6155 } 6156 6157 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 6158 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 6159 // This is a declaration of or a reference to "std::bad_alloc". 6160 isStdBadAlloc = true; 6161 6162 if (Previous.empty() && StdBadAlloc) { 6163 // std::bad_alloc has been implicitly declared (but made invisible to 6164 // name lookup). Fill in this implicit declaration as the previous 6165 // declaration, so that the declarations get chained appropriately. 6166 Previous.addDecl(getStdBadAlloc()); 6167 } 6168 } 6169 6170 // If we didn't find a previous declaration, and this is a reference 6171 // (or friend reference), move to the correct scope. In C++, we 6172 // also need to do a redeclaration lookup there, just in case 6173 // there's a shadow friend decl. 6174 if (Name && Previous.empty() && 6175 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6176 if (Invalid) goto CreateNewDecl; 6177 assert(SS.isEmpty()); 6178 6179 if (TUK == TUK_Reference) { 6180 // C++ [basic.scope.pdecl]p5: 6181 // -- for an elaborated-type-specifier of the form 6182 // 6183 // class-key identifier 6184 // 6185 // if the elaborated-type-specifier is used in the 6186 // decl-specifier-seq or parameter-declaration-clause of a 6187 // function defined in namespace scope, the identifier is 6188 // declared as a class-name in the namespace that contains 6189 // the declaration; otherwise, except as a friend 6190 // declaration, the identifier is declared in the smallest 6191 // non-class, non-function-prototype scope that contains the 6192 // declaration. 6193 // 6194 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 6195 // C structs and unions. 6196 // 6197 // It is an error in C++ to declare (rather than define) an enum 6198 // type, including via an elaborated type specifier. We'll 6199 // diagnose that later; for now, declare the enum in the same 6200 // scope as we would have picked for any other tag type. 6201 // 6202 // GNU C also supports this behavior as part of its incomplete 6203 // enum types extension, while GNU C++ does not. 6204 // 6205 // Find the context where we'll be declaring the tag. 6206 // FIXME: We would like to maintain the current DeclContext as the 6207 // lexical context, 6208 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 6209 SearchDC = SearchDC->getParent(); 6210 6211 // Find the scope where we'll be declaring the tag. 6212 while (S->isClassScope() || 6213 (getLangOptions().CPlusPlus && 6214 S->isFunctionPrototypeScope()) || 6215 ((S->getFlags() & Scope::DeclScope) == 0) || 6216 (S->getEntity() && 6217 ((DeclContext *)S->getEntity())->isTransparentContext())) 6218 S = S->getParent(); 6219 } else { 6220 assert(TUK == TUK_Friend); 6221 // C++ [namespace.memdef]p3: 6222 // If a friend declaration in a non-local class first declares a 6223 // class or function, the friend class or function is a member of 6224 // the innermost enclosing namespace. 6225 SearchDC = SearchDC->getEnclosingNamespaceContext(); 6226 } 6227 6228 // In C++, we need to do a redeclaration lookup to properly 6229 // diagnose some problems. 6230 if (getLangOptions().CPlusPlus) { 6231 Previous.setRedeclarationKind(ForRedeclaration); 6232 LookupQualifiedName(Previous, SearchDC); 6233 } 6234 } 6235 6236 if (!Previous.empty()) { 6237 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 6238 6239 // It's okay to have a tag decl in the same scope as a typedef 6240 // which hides a tag decl in the same scope. Finding this 6241 // insanity with a redeclaration lookup can only actually happen 6242 // in C++. 6243 // 6244 // This is also okay for elaborated-type-specifiers, which is 6245 // technically forbidden by the current standard but which is 6246 // okay according to the likely resolution of an open issue; 6247 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 6248 if (getLangOptions().CPlusPlus) { 6249 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 6250 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 6251 TagDecl *Tag = TT->getDecl(); 6252 if (Tag->getDeclName() == Name && 6253 Tag->getDeclContext()->getRedeclContext() 6254 ->Equals(TD->getDeclContext()->getRedeclContext())) { 6255 PrevDecl = Tag; 6256 Previous.clear(); 6257 Previous.addDecl(Tag); 6258 Previous.resolveKind(); 6259 } 6260 } 6261 } 6262 } 6263 6264 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 6265 // If this is a use of a previous tag, or if the tag is already declared 6266 // in the same scope (so that the definition/declaration completes or 6267 // rementions the tag), reuse the decl. 6268 if (TUK == TUK_Reference || TUK == TUK_Friend || 6269 isDeclInScope(PrevDecl, SearchDC, S)) { 6270 // Make sure that this wasn't declared as an enum and now used as a 6271 // struct or something similar. 6272 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 6273 bool SafeToContinue 6274 = (PrevTagDecl->getTagKind() != TTK_Enum && 6275 Kind != TTK_Enum); 6276 if (SafeToContinue) 6277 Diag(KWLoc, diag::err_use_with_wrong_tag) 6278 << Name 6279 << FixItHint::CreateReplacement(SourceRange(KWLoc), 6280 PrevTagDecl->getKindName()); 6281 else 6282 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 6283 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6284 6285 if (SafeToContinue) 6286 Kind = PrevTagDecl->getTagKind(); 6287 else { 6288 // Recover by making this an anonymous redefinition. 6289 Name = 0; 6290 Previous.clear(); 6291 Invalid = true; 6292 } 6293 } 6294 6295 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 6296 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 6297 6298 // All conflicts with previous declarations are recovered by 6299 // returning the previous declaration. 6300 if (ScopedEnum != PrevEnum->isScoped()) { 6301 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 6302 << PrevEnum->isScoped(); 6303 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6304 return PrevTagDecl; 6305 } 6306 else if (EnumUnderlying && PrevEnum->isFixed()) { 6307 QualType T; 6308 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6309 T = TI->getType(); 6310 else 6311 T = QualType(EnumUnderlying.get<const Type*>(), 0); 6312 6313 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 6314 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 6315 diag::err_enum_redeclare_type_mismatch) 6316 << T 6317 << PrevEnum->getIntegerType(); 6318 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6319 return PrevTagDecl; 6320 } 6321 } 6322 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 6323 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 6324 << PrevEnum->isFixed(); 6325 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6326 return PrevTagDecl; 6327 } 6328 } 6329 6330 if (!Invalid) { 6331 // If this is a use, just return the declaration we found. 6332 6333 // FIXME: In the future, return a variant or some other clue 6334 // for the consumer of this Decl to know it doesn't own it. 6335 // For our current ASTs this shouldn't be a problem, but will 6336 // need to be changed with DeclGroups. 6337 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 6338 TUK == TUK_Friend) 6339 return PrevTagDecl; 6340 6341 // Diagnose attempts to redefine a tag. 6342 if (TUK == TUK_Definition) { 6343 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 6344 // If we're defining a specialization and the previous definition 6345 // is from an implicit instantiation, don't emit an error 6346 // here; we'll catch this in the general case below. 6347 if (!isExplicitSpecialization || 6348 !isa<CXXRecordDecl>(Def) || 6349 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 6350 == TSK_ExplicitSpecialization) { 6351 Diag(NameLoc, diag::err_redefinition) << Name; 6352 Diag(Def->getLocation(), diag::note_previous_definition); 6353 // If this is a redefinition, recover by making this 6354 // struct be anonymous, which will make any later 6355 // references get the previous definition. 6356 Name = 0; 6357 Previous.clear(); 6358 Invalid = true; 6359 } 6360 } else { 6361 // If the type is currently being defined, complain 6362 // about a nested redefinition. 6363 const TagType *Tag 6364 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 6365 if (Tag->isBeingDefined()) { 6366 Diag(NameLoc, diag::err_nested_redefinition) << Name; 6367 Diag(PrevTagDecl->getLocation(), 6368 diag::note_previous_definition); 6369 Name = 0; 6370 Previous.clear(); 6371 Invalid = true; 6372 } 6373 } 6374 6375 // Okay, this is definition of a previously declared or referenced 6376 // tag PrevDecl. We're going to create a new Decl for it. 6377 } 6378 } 6379 // If we get here we have (another) forward declaration or we 6380 // have a definition. Just create a new decl. 6381 6382 } else { 6383 // If we get here, this is a definition of a new tag type in a nested 6384 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 6385 // new decl/type. We set PrevDecl to NULL so that the entities 6386 // have distinct types. 6387 Previous.clear(); 6388 } 6389 // If we get here, we're going to create a new Decl. If PrevDecl 6390 // is non-NULL, it's a definition of the tag declared by 6391 // PrevDecl. If it's NULL, we have a new definition. 6392 6393 6394 // Otherwise, PrevDecl is not a tag, but was found with tag 6395 // lookup. This is only actually possible in C++, where a few 6396 // things like templates still live in the tag namespace. 6397 } else { 6398 assert(getLangOptions().CPlusPlus); 6399 6400 // Use a better diagnostic if an elaborated-type-specifier 6401 // found the wrong kind of type on the first 6402 // (non-redeclaration) lookup. 6403 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 6404 !Previous.isForRedeclaration()) { 6405 unsigned Kind = 0; 6406 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6407 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6408 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 6409 Diag(PrevDecl->getLocation(), diag::note_declared_at); 6410 Invalid = true; 6411 6412 // Otherwise, only diagnose if the declaration is in scope. 6413 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 6414 // do nothing 6415 6416 // Diagnose implicit declarations introduced by elaborated types. 6417 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 6418 unsigned Kind = 0; 6419 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6420 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6421 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 6422 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6423 Invalid = true; 6424 6425 // Otherwise it's a declaration. Call out a particularly common 6426 // case here. 6427 } else if (isa<TypedefDecl>(PrevDecl)) { 6428 Diag(NameLoc, diag::err_tag_definition_of_typedef) 6429 << Name 6430 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 6431 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6432 Invalid = true; 6433 6434 // Otherwise, diagnose. 6435 } else { 6436 // The tag name clashes with something else in the target scope, 6437 // issue an error and recover by making this tag be anonymous. 6438 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 6439 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6440 Name = 0; 6441 Invalid = true; 6442 } 6443 6444 // The existing declaration isn't relevant to us; we're in a 6445 // new scope, so clear out the previous declaration. 6446 Previous.clear(); 6447 } 6448 } 6449 6450CreateNewDecl: 6451 6452 TagDecl *PrevDecl = 0; 6453 if (Previous.isSingleResult()) 6454 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 6455 6456 // If there is an identifier, use the location of the identifier as the 6457 // location of the decl, otherwise use the location of the struct/union 6458 // keyword. 6459 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 6460 6461 // Otherwise, create a new declaration. If there is a previous 6462 // declaration of the same entity, the two will be linked via 6463 // PrevDecl. 6464 TagDecl *New; 6465 6466 bool IsForwardReference = false; 6467 if (Kind == TTK_Enum) { 6468 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6469 // enum X { A, B, C } D; D should chain to X. 6470 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 6471 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 6472 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 6473 // If this is an undefined enum, warn. 6474 if (TUK != TUK_Definition && !Invalid) { 6475 TagDecl *Def; 6476 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 6477 // C++0x: 7.2p2: opaque-enum-declaration. 6478 // Conflicts are diagnosed above. Do nothing. 6479 } 6480 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 6481 Diag(Loc, diag::ext_forward_ref_enum_def) 6482 << New; 6483 Diag(Def->getLocation(), diag::note_previous_definition); 6484 } else { 6485 unsigned DiagID = diag::ext_forward_ref_enum; 6486 if (getLangOptions().Microsoft) 6487 DiagID = diag::ext_ms_forward_ref_enum; 6488 else if (getLangOptions().CPlusPlus) 6489 DiagID = diag::err_forward_ref_enum; 6490 Diag(Loc, DiagID); 6491 6492 // If this is a forward-declared reference to an enumeration, make a 6493 // note of it; we won't actually be introducing the declaration into 6494 // the declaration context. 6495 if (TUK == TUK_Reference) 6496 IsForwardReference = true; 6497 } 6498 } 6499 6500 if (EnumUnderlying) { 6501 EnumDecl *ED = cast<EnumDecl>(New); 6502 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6503 ED->setIntegerTypeSourceInfo(TI); 6504 else 6505 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 6506 ED->setPromotionType(ED->getIntegerType()); 6507 } 6508 6509 } else { 6510 // struct/union/class 6511 6512 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6513 // struct X { int A; } D; D should chain to X. 6514 if (getLangOptions().CPlusPlus) { 6515 // FIXME: Look for a way to use RecordDecl for simple structs. 6516 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 6517 cast_or_null<CXXRecordDecl>(PrevDecl)); 6518 6519 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 6520 StdBadAlloc = cast<CXXRecordDecl>(New); 6521 } else 6522 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 6523 cast_or_null<RecordDecl>(PrevDecl)); 6524 } 6525 6526 // Maybe add qualifier info. 6527 if (SS.isNotEmpty()) { 6528 if (SS.isSet()) { 6529 New->setQualifierInfo(SS.getWithLocInContext(Context)); 6530 if (NumMatchedTemplateParamLists > 0) { 6531 New->setTemplateParameterListsInfo(Context, 6532 NumMatchedTemplateParamLists, 6533 (TemplateParameterList**) TemplateParameterLists.release()); 6534 } 6535 } 6536 else 6537 Invalid = true; 6538 } 6539 6540 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 6541 // Add alignment attributes if necessary; these attributes are checked when 6542 // the ASTContext lays out the structure. 6543 // 6544 // It is important for implementing the correct semantics that this 6545 // happen here (in act on tag decl). The #pragma pack stack is 6546 // maintained as a result of parser callbacks which can occur at 6547 // many points during the parsing of a struct declaration (because 6548 // the #pragma tokens are effectively skipped over during the 6549 // parsing of the struct). 6550 AddAlignmentAttributesForRecord(RD); 6551 } 6552 6553 // If this is a specialization of a member class (of a class template), 6554 // check the specialization. 6555 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 6556 Invalid = true; 6557 6558 if (Invalid) 6559 New->setInvalidDecl(); 6560 6561 if (Attr) 6562 ProcessDeclAttributeList(S, New, Attr); 6563 6564 // If we're declaring or defining a tag in function prototype scope 6565 // in C, note that this type can only be used within the function. 6566 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6567 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6568 6569 // Set the lexical context. If the tag has a C++ scope specifier, the 6570 // lexical context will be different from the semantic context. 6571 New->setLexicalDeclContext(CurContext); 6572 6573 // Mark this as a friend decl if applicable. 6574 if (TUK == TUK_Friend) 6575 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6576 6577 // Set the access specifier. 6578 if (!Invalid && SearchDC->isRecord()) 6579 SetMemberAccessSpecifier(New, PrevDecl, AS); 6580 6581 if (TUK == TUK_Definition) 6582 New->startDefinition(); 6583 6584 // If this has an identifier, add it to the scope stack. 6585 if (TUK == TUK_Friend) { 6586 // We might be replacing an existing declaration in the lookup tables; 6587 // if so, borrow its access specifier. 6588 if (PrevDecl) 6589 New->setAccess(PrevDecl->getAccess()); 6590 6591 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6592 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6593 if (Name) // can be null along some error paths 6594 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6595 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6596 } else if (Name) { 6597 S = getNonFieldDeclScope(S); 6598 PushOnScopeChains(New, S, !IsForwardReference); 6599 if (IsForwardReference) 6600 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6601 6602 } else { 6603 CurContext->addDecl(New); 6604 } 6605 6606 // If this is the C FILE type, notify the AST context. 6607 if (IdentifierInfo *II = New->getIdentifier()) 6608 if (!New->isInvalidDecl() && 6609 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6610 II->isStr("FILE")) 6611 Context.setFILEDecl(New); 6612 6613 OwnedDecl = true; 6614 return New; 6615} 6616 6617void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6618 AdjustDeclIfTemplate(TagD); 6619 TagDecl *Tag = cast<TagDecl>(TagD); 6620 6621 // Enter the tag context. 6622 PushDeclContext(S, Tag); 6623} 6624 6625void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6626 ClassVirtSpecifiers &CVS, 6627 SourceLocation LBraceLoc) { 6628 AdjustDeclIfTemplate(TagD); 6629 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6630 6631 FieldCollector->StartClass(); 6632 6633 if (!Record->getIdentifier()) 6634 return; 6635 6636 if (CVS.isFinalSpecified()) 6637 Record->addAttr(new (Context) FinalAttr(CVS.getFinalLoc(), Context)); 6638 if (CVS.isExplicitSpecified()) 6639 Record->addAttr(new (Context) ExplicitAttr(CVS.getExplicitLoc(), Context)); 6640 6641 // C++ [class]p2: 6642 // [...] The class-name is also inserted into the scope of the 6643 // class itself; this is known as the injected-class-name. For 6644 // purposes of access checking, the injected-class-name is treated 6645 // as if it were a public member name. 6646 CXXRecordDecl *InjectedClassName 6647 = CXXRecordDecl::Create(Context, Record->getTagKind(), 6648 CurContext, Record->getLocation(), 6649 Record->getIdentifier(), 6650 Record->getTagKeywordLoc(), 6651 /*PrevDecl=*/0, 6652 /*DelayTypeCreation=*/true); 6653 Context.getTypeDeclType(InjectedClassName, Record); 6654 InjectedClassName->setImplicit(); 6655 InjectedClassName->setAccess(AS_public); 6656 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6657 InjectedClassName->setDescribedClassTemplate(Template); 6658 PushOnScopeChains(InjectedClassName, S); 6659 assert(InjectedClassName->isInjectedClassName() && 6660 "Broken injected-class-name"); 6661} 6662 6663void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6664 SourceLocation RBraceLoc) { 6665 AdjustDeclIfTemplate(TagD); 6666 TagDecl *Tag = cast<TagDecl>(TagD); 6667 Tag->setRBraceLoc(RBraceLoc); 6668 6669 if (isa<CXXRecordDecl>(Tag)) 6670 FieldCollector->FinishClass(); 6671 6672 // Exit this scope of this tag's definition. 6673 PopDeclContext(); 6674 6675 // Notify the consumer that we've defined a tag. 6676 Consumer.HandleTagDeclDefinition(Tag); 6677} 6678 6679void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6680 AdjustDeclIfTemplate(TagD); 6681 TagDecl *Tag = cast<TagDecl>(TagD); 6682 Tag->setInvalidDecl(); 6683 6684 // We're undoing ActOnTagStartDefinition here, not 6685 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6686 // the FieldCollector. 6687 6688 PopDeclContext(); 6689} 6690 6691// Note that FieldName may be null for anonymous bitfields. 6692bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6693 QualType FieldTy, const Expr *BitWidth, 6694 bool *ZeroWidth) { 6695 // Default to true; that shouldn't confuse checks for emptiness 6696 if (ZeroWidth) 6697 *ZeroWidth = true; 6698 6699 // C99 6.7.2.1p4 - verify the field type. 6700 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6701 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6702 // Handle incomplete types with specific error. 6703 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6704 return true; 6705 if (FieldName) 6706 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6707 << FieldName << FieldTy << BitWidth->getSourceRange(); 6708 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6709 << FieldTy << BitWidth->getSourceRange(); 6710 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 6711 UPPC_BitFieldWidth)) 6712 return true; 6713 6714 // If the bit-width is type- or value-dependent, don't try to check 6715 // it now. 6716 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6717 return false; 6718 6719 llvm::APSInt Value; 6720 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6721 return true; 6722 6723 if (Value != 0 && ZeroWidth) 6724 *ZeroWidth = false; 6725 6726 // Zero-width bitfield is ok for anonymous field. 6727 if (Value == 0 && FieldName) 6728 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6729 6730 if (Value.isSigned() && Value.isNegative()) { 6731 if (FieldName) 6732 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6733 << FieldName << Value.toString(10); 6734 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6735 << Value.toString(10); 6736 } 6737 6738 if (!FieldTy->isDependentType()) { 6739 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6740 if (Value.getZExtValue() > TypeSize) { 6741 if (!getLangOptions().CPlusPlus) { 6742 if (FieldName) 6743 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6744 << FieldName << (unsigned)Value.getZExtValue() 6745 << (unsigned)TypeSize; 6746 6747 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6748 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6749 } 6750 6751 if (FieldName) 6752 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6753 << FieldName << (unsigned)Value.getZExtValue() 6754 << (unsigned)TypeSize; 6755 else 6756 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6757 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6758 } 6759 } 6760 6761 return false; 6762} 6763 6764/// ActOnField - Each field of a struct/union/class is passed into this in order 6765/// to create a FieldDecl object for it. 6766Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6767 SourceLocation DeclStart, 6768 Declarator &D, ExprTy *BitfieldWidth) { 6769 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6770 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6771 AS_public); 6772 return Res; 6773} 6774 6775/// HandleField - Analyze a field of a C struct or a C++ data member. 6776/// 6777FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6778 SourceLocation DeclStart, 6779 Declarator &D, Expr *BitWidth, 6780 AccessSpecifier AS) { 6781 IdentifierInfo *II = D.getIdentifier(); 6782 SourceLocation Loc = DeclStart; 6783 if (II) Loc = D.getIdentifierLoc(); 6784 6785 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6786 QualType T = TInfo->getType(); 6787 if (getLangOptions().CPlusPlus) { 6788 CheckExtraCXXDefaultArguments(D); 6789 6790 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 6791 UPPC_DataMemberType)) { 6792 D.setInvalidType(); 6793 T = Context.IntTy; 6794 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 6795 } 6796 } 6797 6798 DiagnoseFunctionSpecifiers(D); 6799 6800 if (D.getDeclSpec().isThreadSpecified()) 6801 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6802 6803 // Check to see if this name was declared as a member previously 6804 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6805 LookupName(Previous, S); 6806 assert((Previous.empty() || Previous.isOverloadedResult() || 6807 Previous.isSingleResult()) 6808 && "Lookup of member name should be either overloaded, single or null"); 6809 6810 // If the name is overloaded then get any declaration else get the single result 6811 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6812 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6813 6814 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6815 // Maybe we will complain about the shadowed template parameter. 6816 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6817 // Just pretend that we didn't see the previous declaration. 6818 PrevDecl = 0; 6819 } 6820 6821 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 6822 PrevDecl = 0; 6823 6824 bool Mutable 6825 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 6826 SourceLocation TSSL = D.getSourceRange().getBegin(); 6827 FieldDecl *NewFD 6828 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 6829 AS, PrevDecl, &D); 6830 6831 if (NewFD->isInvalidDecl()) 6832 Record->setInvalidDecl(); 6833 6834 if (NewFD->isInvalidDecl() && PrevDecl) { 6835 // Don't introduce NewFD into scope; there's already something 6836 // with the same name in the same scope. 6837 } else if (II) { 6838 PushOnScopeChains(NewFD, S); 6839 } else 6840 Record->addDecl(NewFD); 6841 6842 return NewFD; 6843} 6844 6845/// \brief Build a new FieldDecl and check its well-formedness. 6846/// 6847/// This routine builds a new FieldDecl given the fields name, type, 6848/// record, etc. \p PrevDecl should refer to any previous declaration 6849/// with the same name and in the same scope as the field to be 6850/// created. 6851/// 6852/// \returns a new FieldDecl. 6853/// 6854/// \todo The Declarator argument is a hack. It will be removed once 6855FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 6856 TypeSourceInfo *TInfo, 6857 RecordDecl *Record, SourceLocation Loc, 6858 bool Mutable, Expr *BitWidth, 6859 SourceLocation TSSL, 6860 AccessSpecifier AS, NamedDecl *PrevDecl, 6861 Declarator *D) { 6862 IdentifierInfo *II = Name.getAsIdentifierInfo(); 6863 bool InvalidDecl = false; 6864 if (D) InvalidDecl = D->isInvalidType(); 6865 6866 // If we receive a broken type, recover by assuming 'int' and 6867 // marking this declaration as invalid. 6868 if (T.isNull()) { 6869 InvalidDecl = true; 6870 T = Context.IntTy; 6871 } 6872 6873 QualType EltTy = Context.getBaseElementType(T); 6874 if (!EltTy->isDependentType() && 6875 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 6876 // Fields of incomplete type force their record to be invalid. 6877 Record->setInvalidDecl(); 6878 InvalidDecl = true; 6879 } 6880 6881 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6882 // than a variably modified type. 6883 if (!InvalidDecl && T->isVariablyModifiedType()) { 6884 bool SizeIsNegative; 6885 llvm::APSInt Oversized; 6886 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 6887 SizeIsNegative, 6888 Oversized); 6889 if (!FixedTy.isNull()) { 6890 Diag(Loc, diag::warn_illegal_constant_array_size); 6891 T = FixedTy; 6892 } else { 6893 if (SizeIsNegative) 6894 Diag(Loc, diag::err_typecheck_negative_array_size); 6895 else if (Oversized.getBoolValue()) 6896 Diag(Loc, diag::err_array_too_large) 6897 << Oversized.toString(10); 6898 else 6899 Diag(Loc, diag::err_typecheck_field_variable_size); 6900 InvalidDecl = true; 6901 } 6902 } 6903 6904 // Fields can not have abstract class types 6905 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 6906 diag::err_abstract_type_in_decl, 6907 AbstractFieldType)) 6908 InvalidDecl = true; 6909 6910 bool ZeroWidth = false; 6911 // If this is declared as a bit-field, check the bit-field. 6912 if (!InvalidDecl && BitWidth && 6913 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 6914 InvalidDecl = true; 6915 BitWidth = 0; 6916 ZeroWidth = false; 6917 } 6918 6919 // Check that 'mutable' is consistent with the type of the declaration. 6920 if (!InvalidDecl && Mutable) { 6921 unsigned DiagID = 0; 6922 if (T->isReferenceType()) 6923 DiagID = diag::err_mutable_reference; 6924 else if (T.isConstQualified()) 6925 DiagID = diag::err_mutable_const; 6926 6927 if (DiagID) { 6928 SourceLocation ErrLoc = Loc; 6929 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 6930 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 6931 Diag(ErrLoc, DiagID); 6932 Mutable = false; 6933 InvalidDecl = true; 6934 } 6935 } 6936 6937 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 6938 BitWidth, Mutable); 6939 if (InvalidDecl) 6940 NewFD->setInvalidDecl(); 6941 6942 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 6943 Diag(Loc, diag::err_duplicate_member) << II; 6944 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6945 NewFD->setInvalidDecl(); 6946 } 6947 6948 if (!InvalidDecl && getLangOptions().CPlusPlus) { 6949 if (Record->isUnion()) { 6950 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6951 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6952 if (RDecl->getDefinition()) { 6953 // C++ [class.union]p1: An object of a class with a non-trivial 6954 // constructor, a non-trivial copy constructor, a non-trivial 6955 // destructor, or a non-trivial copy assignment operator 6956 // cannot be a member of a union, nor can an array of such 6957 // objects. 6958 // TODO: C++0x alters this restriction significantly. 6959 if (CheckNontrivialField(NewFD)) 6960 NewFD->setInvalidDecl(); 6961 } 6962 } 6963 6964 // C++ [class.union]p1: If a union contains a member of reference type, 6965 // the program is ill-formed. 6966 if (EltTy->isReferenceType()) { 6967 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 6968 << NewFD->getDeclName() << EltTy; 6969 NewFD->setInvalidDecl(); 6970 } 6971 } 6972 } 6973 6974 // FIXME: We need to pass in the attributes given an AST 6975 // representation, not a parser representation. 6976 if (D) 6977 // FIXME: What to pass instead of TUScope? 6978 ProcessDeclAttributes(TUScope, NewFD, *D); 6979 6980 if (T.isObjCGCWeak()) 6981 Diag(Loc, diag::warn_attribute_weak_on_field); 6982 6983 NewFD->setAccess(AS); 6984 return NewFD; 6985} 6986 6987bool Sema::CheckNontrivialField(FieldDecl *FD) { 6988 assert(FD); 6989 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 6990 6991 if (FD->isInvalidDecl()) 6992 return true; 6993 6994 QualType EltTy = Context.getBaseElementType(FD->getType()); 6995 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 6996 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 6997 if (RDecl->getDefinition()) { 6998 // We check for copy constructors before constructors 6999 // because otherwise we'll never get complaints about 7000 // copy constructors. 7001 7002 CXXSpecialMember member = CXXInvalid; 7003 if (!RDecl->hasTrivialCopyConstructor()) 7004 member = CXXCopyConstructor; 7005 else if (!RDecl->hasTrivialConstructor()) 7006 member = CXXConstructor; 7007 else if (!RDecl->hasTrivialCopyAssignment()) 7008 member = CXXCopyAssignment; 7009 else if (!RDecl->hasTrivialDestructor()) 7010 member = CXXDestructor; 7011 7012 if (member != CXXInvalid) { 7013 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7014 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7015 DiagnoseNontrivial(RT, member); 7016 return true; 7017 } 7018 } 7019 } 7020 7021 return false; 7022} 7023 7024/// DiagnoseNontrivial - Given that a class has a non-trivial 7025/// special member, figure out why. 7026void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7027 QualType QT(T, 0U); 7028 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7029 7030 // Check whether the member was user-declared. 7031 switch (member) { 7032 case CXXInvalid: 7033 break; 7034 7035 case CXXConstructor: 7036 if (RD->hasUserDeclaredConstructor()) { 7037 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7038 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7039 const FunctionDecl *body = 0; 7040 ci->hasBody(body); 7041 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7042 SourceLocation CtorLoc = ci->getLocation(); 7043 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7044 return; 7045 } 7046 } 7047 7048 assert(0 && "found no user-declared constructors"); 7049 return; 7050 } 7051 break; 7052 7053 case CXXCopyConstructor: 7054 if (RD->hasUserDeclaredCopyConstructor()) { 7055 SourceLocation CtorLoc = 7056 RD->getCopyConstructor(Context, 0)->getLocation(); 7057 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7058 return; 7059 } 7060 break; 7061 7062 case CXXCopyAssignment: 7063 if (RD->hasUserDeclaredCopyAssignment()) { 7064 // FIXME: this should use the location of the copy 7065 // assignment, not the type. 7066 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7067 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7068 return; 7069 } 7070 break; 7071 7072 case CXXDestructor: 7073 if (RD->hasUserDeclaredDestructor()) { 7074 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7075 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7076 return; 7077 } 7078 break; 7079 } 7080 7081 typedef CXXRecordDecl::base_class_iterator base_iter; 7082 7083 // Virtual bases and members inhibit trivial copying/construction, 7084 // but not trivial destruction. 7085 if (member != CXXDestructor) { 7086 // Check for virtual bases. vbases includes indirect virtual bases, 7087 // so we just iterate through the direct bases. 7088 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7089 if (bi->isVirtual()) { 7090 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7091 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7092 return; 7093 } 7094 7095 // Check for virtual methods. 7096 typedef CXXRecordDecl::method_iterator meth_iter; 7097 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 7098 ++mi) { 7099 if (mi->isVirtual()) { 7100 SourceLocation MLoc = mi->getSourceRange().getBegin(); 7101 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 7102 return; 7103 } 7104 } 7105 } 7106 7107 bool (CXXRecordDecl::*hasTrivial)() const; 7108 switch (member) { 7109 case CXXConstructor: 7110 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 7111 case CXXCopyConstructor: 7112 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 7113 case CXXCopyAssignment: 7114 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 7115 case CXXDestructor: 7116 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 7117 default: 7118 assert(0 && "unexpected special member"); return; 7119 } 7120 7121 // Check for nontrivial bases (and recurse). 7122 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 7123 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 7124 assert(BaseRT && "Don't know how to handle dependent bases"); 7125 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 7126 if (!(BaseRecTy->*hasTrivial)()) { 7127 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7128 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 7129 DiagnoseNontrivial(BaseRT, member); 7130 return; 7131 } 7132 } 7133 7134 // Check for nontrivial members (and recurse). 7135 typedef RecordDecl::field_iterator field_iter; 7136 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 7137 ++fi) { 7138 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 7139 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 7140 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 7141 7142 if (!(EltRD->*hasTrivial)()) { 7143 SourceLocation FLoc = (*fi)->getLocation(); 7144 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 7145 DiagnoseNontrivial(EltRT, member); 7146 return; 7147 } 7148 } 7149 } 7150 7151 assert(0 && "found no explanation for non-trivial member"); 7152} 7153 7154/// TranslateIvarVisibility - Translate visibility from a token ID to an 7155/// AST enum value. 7156static ObjCIvarDecl::AccessControl 7157TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 7158 switch (ivarVisibility) { 7159 default: assert(0 && "Unknown visitibility kind"); 7160 case tok::objc_private: return ObjCIvarDecl::Private; 7161 case tok::objc_public: return ObjCIvarDecl::Public; 7162 case tok::objc_protected: return ObjCIvarDecl::Protected; 7163 case tok::objc_package: return ObjCIvarDecl::Package; 7164 } 7165} 7166 7167/// ActOnIvar - Each ivar field of an objective-c class is passed into this 7168/// in order to create an IvarDecl object for it. 7169Decl *Sema::ActOnIvar(Scope *S, 7170 SourceLocation DeclStart, 7171 Decl *IntfDecl, 7172 Declarator &D, ExprTy *BitfieldWidth, 7173 tok::ObjCKeywordKind Visibility) { 7174 7175 IdentifierInfo *II = D.getIdentifier(); 7176 Expr *BitWidth = (Expr*)BitfieldWidth; 7177 SourceLocation Loc = DeclStart; 7178 if (II) Loc = D.getIdentifierLoc(); 7179 7180 // FIXME: Unnamed fields can be handled in various different ways, for 7181 // example, unnamed unions inject all members into the struct namespace! 7182 7183 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7184 QualType T = TInfo->getType(); 7185 7186 if (BitWidth) { 7187 // 6.7.2.1p3, 6.7.2.1p4 7188 if (VerifyBitField(Loc, II, T, BitWidth)) { 7189 D.setInvalidType(); 7190 BitWidth = 0; 7191 } 7192 } else { 7193 // Not a bitfield. 7194 7195 // validate II. 7196 7197 } 7198 if (T->isReferenceType()) { 7199 Diag(Loc, diag::err_ivar_reference_type); 7200 D.setInvalidType(); 7201 } 7202 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7203 // than a variably modified type. 7204 else if (T->isVariablyModifiedType()) { 7205 Diag(Loc, diag::err_typecheck_ivar_variable_size); 7206 D.setInvalidType(); 7207 } 7208 7209 // Get the visibility (access control) for this ivar. 7210 ObjCIvarDecl::AccessControl ac = 7211 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 7212 : ObjCIvarDecl::None; 7213 // Must set ivar's DeclContext to its enclosing interface. 7214 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 7215 ObjCContainerDecl *EnclosingContext; 7216 if (ObjCImplementationDecl *IMPDecl = 7217 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7218 if (!LangOpts.ObjCNonFragileABI2) { 7219 // Case of ivar declared in an implementation. Context is that of its class. 7220 EnclosingContext = IMPDecl->getClassInterface(); 7221 assert(EnclosingContext && "Implementation has no class interface!"); 7222 } 7223 else 7224 EnclosingContext = EnclosingDecl; 7225 } else { 7226 if (ObjCCategoryDecl *CDecl = 7227 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7228 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 7229 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 7230 return 0; 7231 } 7232 } 7233 EnclosingContext = EnclosingDecl; 7234 } 7235 7236 // Construct the decl. 7237 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 7238 EnclosingContext, Loc, II, T, 7239 TInfo, ac, (Expr *)BitfieldWidth); 7240 7241 if (II) { 7242 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 7243 ForRedeclaration); 7244 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 7245 && !isa<TagDecl>(PrevDecl)) { 7246 Diag(Loc, diag::err_duplicate_member) << II; 7247 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7248 NewID->setInvalidDecl(); 7249 } 7250 } 7251 7252 // Process attributes attached to the ivar. 7253 ProcessDeclAttributes(S, NewID, D); 7254 7255 if (D.isInvalidType()) 7256 NewID->setInvalidDecl(); 7257 7258 if (II) { 7259 // FIXME: When interfaces are DeclContexts, we'll need to add 7260 // these to the interface. 7261 S->AddDecl(NewID); 7262 IdResolver.AddDecl(NewID); 7263 } 7264 7265 return NewID; 7266} 7267 7268/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 7269/// class and class extensions. For every class @interface and class 7270/// extension @interface, if the last ivar is a bitfield of any type, 7271/// then add an implicit `char :0` ivar to the end of that interface. 7272void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 7273 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 7274 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 7275 return; 7276 7277 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 7278 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 7279 7280 if (!Ivar->isBitField()) 7281 return; 7282 uint64_t BitFieldSize = 7283 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 7284 if (BitFieldSize == 0) 7285 return; 7286 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 7287 if (!ID) { 7288 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7289 if (!CD->IsClassExtension()) 7290 return; 7291 } 7292 // No need to add this to end of @implementation. 7293 else 7294 return; 7295 } 7296 // All conditions are met. Add a new bitfield to the tail end of ivars. 7297 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 7298 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 7299 7300 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 7301 DeclLoc, 0, 7302 Context.CharTy, 7303 Context.CreateTypeSourceInfo(Context.CharTy), 7304 ObjCIvarDecl::Private, BW, 7305 true); 7306 AllIvarDecls.push_back(Ivar); 7307} 7308 7309void Sema::ActOnFields(Scope* S, 7310 SourceLocation RecLoc, Decl *EnclosingDecl, 7311 Decl **Fields, unsigned NumFields, 7312 SourceLocation LBrac, SourceLocation RBrac, 7313 AttributeList *Attr) { 7314 assert(EnclosingDecl && "missing record or interface decl"); 7315 7316 // If the decl this is being inserted into is invalid, then it may be a 7317 // redeclaration or some other bogus case. Don't try to add fields to it. 7318 if (EnclosingDecl->isInvalidDecl()) { 7319 // FIXME: Deallocate fields? 7320 return; 7321 } 7322 7323 7324 // Verify that all the fields are okay. 7325 unsigned NumNamedMembers = 0; 7326 llvm::SmallVector<FieldDecl*, 32> RecFields; 7327 7328 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 7329 for (unsigned i = 0; i != NumFields; ++i) { 7330 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 7331 7332 // Get the type for the field. 7333 const Type *FDTy = FD->getType().getTypePtr(); 7334 7335 if (!FD->isAnonymousStructOrUnion()) { 7336 // Remember all fields written by the user. 7337 RecFields.push_back(FD); 7338 } 7339 7340 // If the field is already invalid for some reason, don't emit more 7341 // diagnostics about it. 7342 if (FD->isInvalidDecl()) { 7343 EnclosingDecl->setInvalidDecl(); 7344 continue; 7345 } 7346 7347 // C99 6.7.2.1p2: 7348 // A structure or union shall not contain a member with 7349 // incomplete or function type (hence, a structure shall not 7350 // contain an instance of itself, but may contain a pointer to 7351 // an instance of itself), except that the last member of a 7352 // structure with more than one named member may have incomplete 7353 // array type; such a structure (and any union containing, 7354 // possibly recursively, a member that is such a structure) 7355 // shall not be a member of a structure or an element of an 7356 // array. 7357 if (FDTy->isFunctionType()) { 7358 // Field declared as a function. 7359 Diag(FD->getLocation(), diag::err_field_declared_as_function) 7360 << FD->getDeclName(); 7361 FD->setInvalidDecl(); 7362 EnclosingDecl->setInvalidDecl(); 7363 continue; 7364 } else if (FDTy->isIncompleteArrayType() && Record && 7365 ((i == NumFields - 1 && !Record->isUnion()) || 7366 (getLangOptions().Microsoft && 7367 (i == NumFields - 1 || Record->isUnion())))) { 7368 // Flexible array member. 7369 // Microsoft is more permissive regarding flexible array. 7370 // It will accept flexible array in union and also 7371 // as the sole element of a struct/class. 7372 if (getLangOptions().Microsoft) { 7373 if (Record->isUnion()) 7374 Diag(FD->getLocation(), diag::ext_flexible_array_union) 7375 << FD->getDeclName(); 7376 else if (NumFields == 1) 7377 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate) 7378 << FD->getDeclName() << Record->getTagKind(); 7379 } else if (NumNamedMembers < 1) { 7380 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 7381 << FD->getDeclName(); 7382 FD->setInvalidDecl(); 7383 EnclosingDecl->setInvalidDecl(); 7384 continue; 7385 } 7386 if (!FD->getType()->isDependentType() && 7387 !Context.getBaseElementType(FD->getType())->isPODType()) { 7388 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 7389 << FD->getDeclName() << FD->getType(); 7390 FD->setInvalidDecl(); 7391 EnclosingDecl->setInvalidDecl(); 7392 continue; 7393 } 7394 // Okay, we have a legal flexible array member at the end of the struct. 7395 if (Record) 7396 Record->setHasFlexibleArrayMember(true); 7397 } else if (!FDTy->isDependentType() && 7398 RequireCompleteType(FD->getLocation(), FD->getType(), 7399 diag::err_field_incomplete)) { 7400 // Incomplete type 7401 FD->setInvalidDecl(); 7402 EnclosingDecl->setInvalidDecl(); 7403 continue; 7404 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 7405 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 7406 // If this is a member of a union, then entire union becomes "flexible". 7407 if (Record && Record->isUnion()) { 7408 Record->setHasFlexibleArrayMember(true); 7409 } else { 7410 // If this is a struct/class and this is not the last element, reject 7411 // it. Note that GCC supports variable sized arrays in the middle of 7412 // structures. 7413 if (i != NumFields-1) 7414 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 7415 << FD->getDeclName() << FD->getType(); 7416 else { 7417 // We support flexible arrays at the end of structs in 7418 // other structs as an extension. 7419 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 7420 << FD->getDeclName(); 7421 if (Record) 7422 Record->setHasFlexibleArrayMember(true); 7423 } 7424 } 7425 } 7426 if (Record && FDTTy->getDecl()->hasObjectMember()) 7427 Record->setHasObjectMember(true); 7428 } else if (FDTy->isObjCObjectType()) { 7429 /// A field cannot be an Objective-c object 7430 Diag(FD->getLocation(), diag::err_statically_allocated_object); 7431 FD->setInvalidDecl(); 7432 EnclosingDecl->setInvalidDecl(); 7433 continue; 7434 } else if (getLangOptions().ObjC1 && 7435 getLangOptions().getGCMode() != LangOptions::NonGC && 7436 Record && 7437 (FD->getType()->isObjCObjectPointerType() || 7438 FD->getType().isObjCGCStrong())) 7439 Record->setHasObjectMember(true); 7440 else if (Context.getAsArrayType(FD->getType())) { 7441 QualType BaseType = Context.getBaseElementType(FD->getType()); 7442 if (Record && BaseType->isRecordType() && 7443 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 7444 Record->setHasObjectMember(true); 7445 } 7446 // Keep track of the number of named members. 7447 if (FD->getIdentifier()) 7448 ++NumNamedMembers; 7449 } 7450 7451 // Okay, we successfully defined 'Record'. 7452 if (Record) { 7453 bool Completed = false; 7454 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 7455 if (!CXXRecord->isInvalidDecl()) { 7456 // Set access bits correctly on the directly-declared conversions. 7457 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 7458 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 7459 I != E; ++I) 7460 Convs->setAccess(I, (*I)->getAccess()); 7461 7462 if (!CXXRecord->isDependentType()) { 7463 // Add any implicitly-declared members to this class. 7464 AddImplicitlyDeclaredMembersToClass(CXXRecord); 7465 7466 // If we have virtual base classes, we may end up finding multiple 7467 // final overriders for a given virtual function. Check for this 7468 // problem now. 7469 if (CXXRecord->getNumVBases()) { 7470 CXXFinalOverriderMap FinalOverriders; 7471 CXXRecord->getFinalOverriders(FinalOverriders); 7472 7473 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 7474 MEnd = FinalOverriders.end(); 7475 M != MEnd; ++M) { 7476 for (OverridingMethods::iterator SO = M->second.begin(), 7477 SOEnd = M->second.end(); 7478 SO != SOEnd; ++SO) { 7479 assert(SO->second.size() > 0 && 7480 "Virtual function without overridding functions?"); 7481 if (SO->second.size() == 1) 7482 continue; 7483 7484 // C++ [class.virtual]p2: 7485 // In a derived class, if a virtual member function of a base 7486 // class subobject has more than one final overrider the 7487 // program is ill-formed. 7488 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 7489 << (NamedDecl *)M->first << Record; 7490 Diag(M->first->getLocation(), 7491 diag::note_overridden_virtual_function); 7492 for (OverridingMethods::overriding_iterator 7493 OM = SO->second.begin(), 7494 OMEnd = SO->second.end(); 7495 OM != OMEnd; ++OM) 7496 Diag(OM->Method->getLocation(), diag::note_final_overrider) 7497 << (NamedDecl *)M->first << OM->Method->getParent(); 7498 7499 Record->setInvalidDecl(); 7500 } 7501 } 7502 CXXRecord->completeDefinition(&FinalOverriders); 7503 Completed = true; 7504 } 7505 } 7506 } 7507 } 7508 7509 if (!Completed) 7510 Record->completeDefinition(); 7511 } else { 7512 ObjCIvarDecl **ClsFields = 7513 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 7514 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 7515 ID->setLocEnd(RBrac); 7516 // Add ivar's to class's DeclContext. 7517 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7518 ClsFields[i]->setLexicalDeclContext(ID); 7519 ID->addDecl(ClsFields[i]); 7520 } 7521 // Must enforce the rule that ivars in the base classes may not be 7522 // duplicates. 7523 if (ID->getSuperClass()) 7524 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 7525 } else if (ObjCImplementationDecl *IMPDecl = 7526 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7527 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 7528 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 7529 // Ivar declared in @implementation never belongs to the implementation. 7530 // Only it is in implementation's lexical context. 7531 ClsFields[I]->setLexicalDeclContext(IMPDecl); 7532 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 7533 } else if (ObjCCategoryDecl *CDecl = 7534 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7535 // case of ivars in class extension; all other cases have been 7536 // reported as errors elsewhere. 7537 // FIXME. Class extension does not have a LocEnd field. 7538 // CDecl->setLocEnd(RBrac); 7539 // Add ivar's to class extension's DeclContext. 7540 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7541 ClsFields[i]->setLexicalDeclContext(CDecl); 7542 CDecl->addDecl(ClsFields[i]); 7543 } 7544 } 7545 } 7546 7547 if (Attr) 7548 ProcessDeclAttributeList(S, Record, Attr); 7549 7550 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 7551 // set the visibility of this record. 7552 if (Record && !Record->getDeclContext()->isRecord()) 7553 AddPushedVisibilityAttribute(Record); 7554} 7555 7556/// \brief Determine whether the given integral value is representable within 7557/// the given type T. 7558static bool isRepresentableIntegerValue(ASTContext &Context, 7559 llvm::APSInt &Value, 7560 QualType T) { 7561 assert(T->isIntegralType(Context) && "Integral type required!"); 7562 unsigned BitWidth = Context.getIntWidth(T); 7563 7564 if (Value.isUnsigned() || Value.isNonNegative()) { 7565 if (T->isSignedIntegerType()) 7566 --BitWidth; 7567 return Value.getActiveBits() <= BitWidth; 7568 } 7569 return Value.getMinSignedBits() <= BitWidth; 7570} 7571 7572// \brief Given an integral type, return the next larger integral type 7573// (or a NULL type of no such type exists). 7574static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 7575 // FIXME: Int128/UInt128 support, which also needs to be introduced into 7576 // enum checking below. 7577 assert(T->isIntegralType(Context) && "Integral type required!"); 7578 const unsigned NumTypes = 4; 7579 QualType SignedIntegralTypes[NumTypes] = { 7580 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 7581 }; 7582 QualType UnsignedIntegralTypes[NumTypes] = { 7583 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 7584 Context.UnsignedLongLongTy 7585 }; 7586 7587 unsigned BitWidth = Context.getTypeSize(T); 7588 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7589 : UnsignedIntegralTypes; 7590 for (unsigned I = 0; I != NumTypes; ++I) 7591 if (Context.getTypeSize(Types[I]) > BitWidth) 7592 return Types[I]; 7593 7594 return QualType(); 7595} 7596 7597EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7598 EnumConstantDecl *LastEnumConst, 7599 SourceLocation IdLoc, 7600 IdentifierInfo *Id, 7601 Expr *Val) { 7602 unsigned IntWidth = Context.Target.getIntWidth(); 7603 llvm::APSInt EnumVal(IntWidth); 7604 QualType EltTy; 7605 7606 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 7607 Val = 0; 7608 7609 if (Val) { 7610 if (Enum->isDependentType() || Val->isTypeDependent()) 7611 EltTy = Context.DependentTy; 7612 else { 7613 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7614 SourceLocation ExpLoc; 7615 if (!Val->isValueDependent() && 7616 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7617 Val = 0; 7618 } else { 7619 if (!getLangOptions().CPlusPlus) { 7620 // C99 6.7.2.2p2: 7621 // The expression that defines the value of an enumeration constant 7622 // shall be an integer constant expression that has a value 7623 // representable as an int. 7624 7625 // Complain if the value is not representable in an int. 7626 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7627 Diag(IdLoc, diag::ext_enum_value_not_int) 7628 << EnumVal.toString(10) << Val->getSourceRange() 7629 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7630 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7631 // Force the type of the expression to 'int'. 7632 ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast); 7633 } 7634 } 7635 7636 if (Enum->isFixed()) { 7637 EltTy = Enum->getIntegerType(); 7638 7639 // C++0x [dcl.enum]p5: 7640 // ... if the initializing value of an enumerator cannot be 7641 // represented by the underlying type, the program is ill-formed. 7642 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7643 if (getLangOptions().Microsoft) { 7644 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 7645 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7646 } else 7647 Diag(IdLoc, diag::err_enumerator_too_large) 7648 << EltTy; 7649 } else 7650 ImpCastExprToType(Val, EltTy, CK_IntegralCast); 7651 } 7652 else { 7653 // C++0x [dcl.enum]p5: 7654 // If the underlying type is not fixed, the type of each enumerator 7655 // is the type of its initializing value: 7656 // - If an initializer is specified for an enumerator, the 7657 // initializing value has the same type as the expression. 7658 EltTy = Val->getType(); 7659 } 7660 } 7661 } 7662 } 7663 7664 if (!Val) { 7665 if (Enum->isDependentType()) 7666 EltTy = Context.DependentTy; 7667 else if (!LastEnumConst) { 7668 // C++0x [dcl.enum]p5: 7669 // If the underlying type is not fixed, the type of each enumerator 7670 // is the type of its initializing value: 7671 // - If no initializer is specified for the first enumerator, the 7672 // initializing value has an unspecified integral type. 7673 // 7674 // GCC uses 'int' for its unspecified integral type, as does 7675 // C99 6.7.2.2p3. 7676 if (Enum->isFixed()) { 7677 EltTy = Enum->getIntegerType(); 7678 } 7679 else { 7680 EltTy = Context.IntTy; 7681 } 7682 } else { 7683 // Assign the last value + 1. 7684 EnumVal = LastEnumConst->getInitVal(); 7685 ++EnumVal; 7686 EltTy = LastEnumConst->getType(); 7687 7688 // Check for overflow on increment. 7689 if (EnumVal < LastEnumConst->getInitVal()) { 7690 // C++0x [dcl.enum]p5: 7691 // If the underlying type is not fixed, the type of each enumerator 7692 // is the type of its initializing value: 7693 // 7694 // - Otherwise the type of the initializing value is the same as 7695 // the type of the initializing value of the preceding enumerator 7696 // unless the incremented value is not representable in that type, 7697 // in which case the type is an unspecified integral type 7698 // sufficient to contain the incremented value. If no such type 7699 // exists, the program is ill-formed. 7700 QualType T = getNextLargerIntegralType(Context, EltTy); 7701 if (T.isNull() || Enum->isFixed()) { 7702 // There is no integral type larger enough to represent this 7703 // value. Complain, then allow the value to wrap around. 7704 EnumVal = LastEnumConst->getInitVal(); 7705 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 7706 ++EnumVal; 7707 if (Enum->isFixed()) 7708 // When the underlying type is fixed, this is ill-formed. 7709 Diag(IdLoc, diag::err_enumerator_wrapped) 7710 << EnumVal.toString(10) 7711 << EltTy; 7712 else 7713 Diag(IdLoc, diag::warn_enumerator_too_large) 7714 << EnumVal.toString(10); 7715 } else { 7716 EltTy = T; 7717 } 7718 7719 // Retrieve the last enumerator's value, extent that type to the 7720 // type that is supposed to be large enough to represent the incremented 7721 // value, then increment. 7722 EnumVal = LastEnumConst->getInitVal(); 7723 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7724 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7725 ++EnumVal; 7726 7727 // If we're not in C++, diagnose the overflow of enumerator values, 7728 // which in C99 means that the enumerator value is not representable in 7729 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7730 // permits enumerator values that are representable in some larger 7731 // integral type. 7732 if (!getLangOptions().CPlusPlus && !T.isNull()) 7733 Diag(IdLoc, diag::warn_enum_value_overflow); 7734 } else if (!getLangOptions().CPlusPlus && 7735 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7736 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7737 Diag(IdLoc, diag::ext_enum_value_not_int) 7738 << EnumVal.toString(10) << 1; 7739 } 7740 } 7741 } 7742 7743 if (!EltTy->isDependentType()) { 7744 // Make the enumerator value match the signedness and size of the 7745 // enumerator's type. 7746 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7747 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7748 } 7749 7750 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7751 Val, EnumVal); 7752} 7753 7754 7755Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 7756 SourceLocation IdLoc, IdentifierInfo *Id, 7757 AttributeList *Attr, 7758 SourceLocation EqualLoc, ExprTy *val) { 7759 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7760 EnumConstantDecl *LastEnumConst = 7761 cast_or_null<EnumConstantDecl>(lastEnumConst); 7762 Expr *Val = static_cast<Expr*>(val); 7763 7764 // The scope passed in may not be a decl scope. Zip up the scope tree until 7765 // we find one that is. 7766 S = getNonFieldDeclScope(S); 7767 7768 // Verify that there isn't already something declared with this name in this 7769 // scope. 7770 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7771 ForRedeclaration); 7772 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7773 // Maybe we will complain about the shadowed template parameter. 7774 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7775 // Just pretend that we didn't see the previous declaration. 7776 PrevDecl = 0; 7777 } 7778 7779 if (PrevDecl) { 7780 // When in C++, we may get a TagDecl with the same name; in this case the 7781 // enum constant will 'hide' the tag. 7782 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7783 "Received TagDecl when not in C++!"); 7784 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7785 if (isa<EnumConstantDecl>(PrevDecl)) 7786 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7787 else 7788 Diag(IdLoc, diag::err_redefinition) << Id; 7789 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7790 return 0; 7791 } 7792 } 7793 7794 // C++ [class.mem]p13: 7795 // If T is the name of a class, then each of the following shall have a 7796 // name different from T: 7797 // - every enumerator of every member of class T that is an enumerated 7798 // type 7799 if (CXXRecordDecl *Record 7800 = dyn_cast<CXXRecordDecl>( 7801 TheEnumDecl->getDeclContext()->getRedeclContext())) 7802 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7803 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7804 7805 EnumConstantDecl *New = 7806 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 7807 7808 if (New) { 7809 // Process attributes. 7810 if (Attr) ProcessDeclAttributeList(S, New, Attr); 7811 7812 // Register this decl in the current scope stack. 7813 New->setAccess(TheEnumDecl->getAccess()); 7814 PushOnScopeChains(New, S); 7815 } 7816 7817 return New; 7818} 7819 7820void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 7821 SourceLocation RBraceLoc, Decl *EnumDeclX, 7822 Decl **Elements, unsigned NumElements, 7823 Scope *S, AttributeList *Attr) { 7824 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 7825 QualType EnumType = Context.getTypeDeclType(Enum); 7826 7827 if (Attr) 7828 ProcessDeclAttributeList(S, Enum, Attr); 7829 7830 if (Enum->isDependentType()) { 7831 for (unsigned i = 0; i != NumElements; ++i) { 7832 EnumConstantDecl *ECD = 7833 cast_or_null<EnumConstantDecl>(Elements[i]); 7834 if (!ECD) continue; 7835 7836 ECD->setType(EnumType); 7837 } 7838 7839 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 7840 return; 7841 } 7842 7843 // TODO: If the result value doesn't fit in an int, it must be a long or long 7844 // long value. ISO C does not support this, but GCC does as an extension, 7845 // emit a warning. 7846 unsigned IntWidth = Context.Target.getIntWidth(); 7847 unsigned CharWidth = Context.Target.getCharWidth(); 7848 unsigned ShortWidth = Context.Target.getShortWidth(); 7849 7850 // Verify that all the values are okay, compute the size of the values, and 7851 // reverse the list. 7852 unsigned NumNegativeBits = 0; 7853 unsigned NumPositiveBits = 0; 7854 7855 // Keep track of whether all elements have type int. 7856 bool AllElementsInt = true; 7857 7858 for (unsigned i = 0; i != NumElements; ++i) { 7859 EnumConstantDecl *ECD = 7860 cast_or_null<EnumConstantDecl>(Elements[i]); 7861 if (!ECD) continue; // Already issued a diagnostic. 7862 7863 const llvm::APSInt &InitVal = ECD->getInitVal(); 7864 7865 // Keep track of the size of positive and negative values. 7866 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 7867 NumPositiveBits = std::max(NumPositiveBits, 7868 (unsigned)InitVal.getActiveBits()); 7869 else 7870 NumNegativeBits = std::max(NumNegativeBits, 7871 (unsigned)InitVal.getMinSignedBits()); 7872 7873 // Keep track of whether every enum element has type int (very commmon). 7874 if (AllElementsInt) 7875 AllElementsInt = ECD->getType() == Context.IntTy; 7876 } 7877 7878 // Figure out the type that should be used for this enum. 7879 QualType BestType; 7880 unsigned BestWidth; 7881 7882 // C++0x N3000 [conv.prom]p3: 7883 // An rvalue of an unscoped enumeration type whose underlying 7884 // type is not fixed can be converted to an rvalue of the first 7885 // of the following types that can represent all the values of 7886 // the enumeration: int, unsigned int, long int, unsigned long 7887 // int, long long int, or unsigned long long int. 7888 // C99 6.4.4.3p2: 7889 // An identifier declared as an enumeration constant has type int. 7890 // The C99 rule is modified by a gcc extension 7891 QualType BestPromotionType; 7892 7893 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 7894 // -fshort-enums is the equivalent to specifying the packed attribute on all 7895 // enum definitions. 7896 if (LangOpts.ShortEnums) 7897 Packed = true; 7898 7899 if (Enum->isFixed()) { 7900 BestType = BestPromotionType = Enum->getIntegerType(); 7901 // We don't need to set BestWidth, because BestType is going to be the type 7902 // of the enumerators, but we do anyway because otherwise some compilers 7903 // warn that it might be used uninitialized. 7904 BestWidth = CharWidth; 7905 } 7906 else if (NumNegativeBits) { 7907 // If there is a negative value, figure out the smallest integer type (of 7908 // int/long/longlong) that fits. 7909 // If it's packed, check also if it fits a char or a short. 7910 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 7911 BestType = Context.SignedCharTy; 7912 BestWidth = CharWidth; 7913 } else if (Packed && NumNegativeBits <= ShortWidth && 7914 NumPositiveBits < ShortWidth) { 7915 BestType = Context.ShortTy; 7916 BestWidth = ShortWidth; 7917 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 7918 BestType = Context.IntTy; 7919 BestWidth = IntWidth; 7920 } else { 7921 BestWidth = Context.Target.getLongWidth(); 7922 7923 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 7924 BestType = Context.LongTy; 7925 } else { 7926 BestWidth = Context.Target.getLongLongWidth(); 7927 7928 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 7929 Diag(Enum->getLocation(), diag::warn_enum_too_large); 7930 BestType = Context.LongLongTy; 7931 } 7932 } 7933 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 7934 } else { 7935 // If there is no negative value, figure out the smallest type that fits 7936 // all of the enumerator values. 7937 // If it's packed, check also if it fits a char or a short. 7938 if (Packed && NumPositiveBits <= CharWidth) { 7939 BestType = Context.UnsignedCharTy; 7940 BestPromotionType = Context.IntTy; 7941 BestWidth = CharWidth; 7942 } else if (Packed && NumPositiveBits <= ShortWidth) { 7943 BestType = Context.UnsignedShortTy; 7944 BestPromotionType = Context.IntTy; 7945 BestWidth = ShortWidth; 7946 } else if (NumPositiveBits <= IntWidth) { 7947 BestType = Context.UnsignedIntTy; 7948 BestWidth = IntWidth; 7949 BestPromotionType 7950 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7951 ? Context.UnsignedIntTy : Context.IntTy; 7952 } else if (NumPositiveBits <= 7953 (BestWidth = Context.Target.getLongWidth())) { 7954 BestType = Context.UnsignedLongTy; 7955 BestPromotionType 7956 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7957 ? Context.UnsignedLongTy : Context.LongTy; 7958 } else { 7959 BestWidth = Context.Target.getLongLongWidth(); 7960 assert(NumPositiveBits <= BestWidth && 7961 "How could an initializer get larger than ULL?"); 7962 BestType = Context.UnsignedLongLongTy; 7963 BestPromotionType 7964 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 7965 ? Context.UnsignedLongLongTy : Context.LongLongTy; 7966 } 7967 } 7968 7969 // Loop over all of the enumerator constants, changing their types to match 7970 // the type of the enum if needed. 7971 for (unsigned i = 0; i != NumElements; ++i) { 7972 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 7973 if (!ECD) continue; // Already issued a diagnostic. 7974 7975 // Standard C says the enumerators have int type, but we allow, as an 7976 // extension, the enumerators to be larger than int size. If each 7977 // enumerator value fits in an int, type it as an int, otherwise type it the 7978 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 7979 // that X has type 'int', not 'unsigned'. 7980 7981 // Determine whether the value fits into an int. 7982 llvm::APSInt InitVal = ECD->getInitVal(); 7983 7984 // If it fits into an integer type, force it. Otherwise force it to match 7985 // the enum decl type. 7986 QualType NewTy; 7987 unsigned NewWidth; 7988 bool NewSign; 7989 if (!getLangOptions().CPlusPlus && 7990 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 7991 NewTy = Context.IntTy; 7992 NewWidth = IntWidth; 7993 NewSign = true; 7994 } else if (ECD->getType() == BestType) { 7995 // Already the right type! 7996 if (getLangOptions().CPlusPlus) 7997 // C++ [dcl.enum]p4: Following the closing brace of an 7998 // enum-specifier, each enumerator has the type of its 7999 // enumeration. 8000 ECD->setType(EnumType); 8001 continue; 8002 } else { 8003 NewTy = BestType; 8004 NewWidth = BestWidth; 8005 NewSign = BestType->isSignedIntegerType(); 8006 } 8007 8008 // Adjust the APSInt value. 8009 InitVal = InitVal.extOrTrunc(NewWidth); 8010 InitVal.setIsSigned(NewSign); 8011 ECD->setInitVal(InitVal); 8012 8013 // Adjust the Expr initializer and type. 8014 if (ECD->getInitExpr() && 8015 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 8016 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 8017 CK_IntegralCast, 8018 ECD->getInitExpr(), 8019 /*base paths*/ 0, 8020 VK_RValue)); 8021 if (getLangOptions().CPlusPlus) 8022 // C++ [dcl.enum]p4: Following the closing brace of an 8023 // enum-specifier, each enumerator has the type of its 8024 // enumeration. 8025 ECD->setType(EnumType); 8026 else 8027 ECD->setType(NewTy); 8028 } 8029 8030 Enum->completeDefinition(BestType, BestPromotionType, 8031 NumPositiveBits, NumNegativeBits); 8032} 8033 8034Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 8035 SourceLocation StartLoc, 8036 SourceLocation EndLoc) { 8037 StringLiteral *AsmString = cast<StringLiteral>(expr); 8038 8039 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 8040 AsmString, StartLoc, 8041 EndLoc); 8042 CurContext->addDecl(New); 8043 return New; 8044} 8045 8046void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 8047 SourceLocation PragmaLoc, 8048 SourceLocation NameLoc) { 8049 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 8050 8051 if (PrevDecl) { 8052 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 8053 } else { 8054 (void)WeakUndeclaredIdentifiers.insert( 8055 std::pair<IdentifierInfo*,WeakInfo> 8056 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 8057 } 8058} 8059 8060void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 8061 IdentifierInfo* AliasName, 8062 SourceLocation PragmaLoc, 8063 SourceLocation NameLoc, 8064 SourceLocation AliasNameLoc) { 8065 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 8066 LookupOrdinaryName); 8067 WeakInfo W = WeakInfo(Name, NameLoc); 8068 8069 if (PrevDecl) { 8070 if (!PrevDecl->hasAttr<AliasAttr>()) 8071 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 8072 DeclApplyPragmaWeak(TUScope, ND, W); 8073 } else { 8074 (void)WeakUndeclaredIdentifiers.insert( 8075 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 8076 } 8077} 8078