SemaDecl.cpp revision 275313cbb0847f1f117f60d144d113804d4fa42d
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 "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isSet()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, so build a 91 // TypenameType node to describe the type. 92 // FIXME: Record somewhere that this TypenameType node has no "typename" 93 // keyword associated with it. 94 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 95 II, SS->getRange()).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 102 return 0; 103 } 104 105 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 106 // lookup for class-names. 107 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 108 LookupOrdinaryName; 109 LookupResult Result(*this, &II, NameLoc, Kind); 110 if (LookupCtx) { 111 // Perform "qualified" name lookup into the declaration context we 112 // computed, which is either the type of the base of a member access 113 // expression or the declaration context associated with a prior 114 // nested-name-specifier. 115 LookupQualifiedName(Result, LookupCtx); 116 117 if (ObjectTypePtr && Result.empty()) { 118 // C++ [basic.lookup.classref]p3: 119 // If the unqualified-id is ~type-name, the type-name is looked up 120 // in the context of the entire postfix-expression. If the type T of 121 // the object expression is of a class type C, the type-name is also 122 // looked up in the scope of class C. At least one of the lookups shall 123 // find a name that refers to (possibly cv-qualified) T. 124 LookupName(Result, S); 125 } 126 } else { 127 // Perform unqualified name lookup. 128 LookupName(Result, S); 129 } 130 131 NamedDecl *IIDecl = 0; 132 switch (Result.getResultKind()) { 133 case LookupResult::NotFound: 134 case LookupResult::NotFoundInCurrentInstantiation: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 Result.suppressDiagnostics(); 138 return 0; 139 140 case LookupResult::Ambiguous: 141 // Recover from type-hiding ambiguities by hiding the type. We'll 142 // do the lookup again when looking for an object, and we can 143 // diagnose the error then. If we don't do this, then the error 144 // about hiding the type will be immediately followed by an error 145 // that only makes sense if the identifier was treated like a type. 146 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 147 Result.suppressDiagnostics(); 148 return 0; 149 } 150 151 // Look to see if we have a type anywhere in the list of results. 152 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 153 Res != ResEnd; ++Res) { 154 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 155 if (!IIDecl || 156 (*Res)->getLocation().getRawEncoding() < 157 IIDecl->getLocation().getRawEncoding()) 158 IIDecl = *Res; 159 } 160 } 161 162 if (!IIDecl) { 163 // None of the entities we found is a type, so there is no way 164 // to even assume that the result is a type. In this case, don't 165 // complain about the ambiguity. The parser will either try to 166 // perform this lookup again (e.g., as an object name), which 167 // will produce the ambiguity, or will complain that it expected 168 // a type name. 169 Result.suppressDiagnostics(); 170 return 0; 171 } 172 173 // We found a type within the ambiguous lookup; diagnose the 174 // ambiguity and then return that type. This might be the right 175 // answer, or it might not be, but it suppresses any attempt to 176 // perform the name lookup again. 177 break; 178 179 case LookupResult::Found: 180 IIDecl = Result.getFoundDecl(); 181 break; 182 } 183 184 assert(IIDecl && "Didn't find decl"); 185 186 QualType T; 187 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 188 DiagnoseUseOfDecl(IIDecl, NameLoc); 189 190 if (T.isNull()) 191 T = Context.getTypeDeclType(TD); 192 193 if (SS) 194 T = getQualifiedNameType(*SS, T); 195 196 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 197 T = Context.getObjCInterfaceType(IDecl); 198 } else if (UnresolvedUsingTypenameDecl *UUDecl = 199 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 200 // FIXME: preserve source structure information. 201 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 202 } else { 203 // If it's not plausibly a type, suppress diagnostics. 204 Result.suppressDiagnostics(); 205 return 0; 206 } 207 208 return T.getAsOpaquePtr(); 209} 210 211/// isTagName() - This method is called *for error recovery purposes only* 212/// to determine if the specified name is a valid tag name ("struct foo"). If 213/// so, this returns the TST for the tag corresponding to it (TST_enum, 214/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 215/// where the user forgot to specify the tag. 216DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 217 // Do a tag name lookup in this scope. 218 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 219 LookupName(R, S, false); 220 R.suppressDiagnostics(); 221 if (R.getResultKind() == LookupResult::Found) 222 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 223 switch (TD->getTagKind()) { 224 case TagDecl::TK_struct: return DeclSpec::TST_struct; 225 case TagDecl::TK_union: return DeclSpec::TST_union; 226 case TagDecl::TK_class: return DeclSpec::TST_class; 227 case TagDecl::TK_enum: return DeclSpec::TST_enum; 228 } 229 } 230 231 return DeclSpec::TST_unspecified; 232} 233 234bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 235 SourceLocation IILoc, 236 Scope *S, 237 const CXXScopeSpec *SS, 238 TypeTy *&SuggestedType) { 239 // We don't have anything to suggest (yet). 240 SuggestedType = 0; 241 242 // There may have been a typo in the name of the type. Look up typo 243 // results, in case we have something that we can suggest. 244 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 245 NotForRedeclaration); 246 247 // FIXME: It would be nice if we could correct for typos in built-in 248 // names, such as "itn" for "int". 249 250 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 251 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 252 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 253 !Result->isInvalidDecl()) { 254 // We found a similarly-named type or interface; suggest that. 255 if (!SS || !SS->isSet()) 256 Diag(IILoc, diag::err_unknown_typename_suggest) 257 << &II << Lookup.getLookupName() 258 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else if (DeclContext *DC = computeDeclContext(*SS, false)) 261 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 262 << &II << DC << Lookup.getLookupName() << SS->getRange() 263 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 264 Result->getNameAsString()); 265 else 266 llvm_unreachable("could not have corrected a typo here"); 267 268 Diag(Result->getLocation(), diag::note_previous_decl) 269 << Result->getDeclName(); 270 271 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 272 return true; 273 } 274 } 275 276 // FIXME: Should we move the logic that tries to recover from a missing tag 277 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 278 279 if (!SS || (!SS->isSet() && !SS->isInvalid())) 280 Diag(IILoc, diag::err_unknown_typename) << &II; 281 else if (DeclContext *DC = computeDeclContext(*SS, false)) 282 Diag(IILoc, diag::err_typename_nested_not_found) 283 << &II << DC << SS->getRange(); 284 else if (isDependentScopeSpecifier(*SS)) { 285 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 286 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 287 << SourceRange(SS->getRange().getBegin(), IILoc) 288 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 289 "typename "); 290 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 291 } else { 292 assert(SS && SS->isInvalid() && 293 "Invalid scope specifier has already been diagnosed"); 294 } 295 296 return true; 297} 298 299// Determines the context to return to after temporarily entering a 300// context. This depends in an unnecessarily complicated way on the 301// exact ordering of callbacks from the parser. 302DeclContext *Sema::getContainingDC(DeclContext *DC) { 303 304 // Functions defined inline within classes aren't parsed until we've 305 // finished parsing the top-level class, so the top-level class is 306 // the context we'll need to return to. 307 if (isa<FunctionDecl>(DC)) { 308 DC = DC->getLexicalParent(); 309 310 // A function not defined within a class will always return to its 311 // lexical context. 312 if (!isa<CXXRecordDecl>(DC)) 313 return DC; 314 315 // A C++ inline method/friend is parsed *after* the topmost class 316 // it was declared in is fully parsed ("complete"); the topmost 317 // class is the context we need to return to. 318 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 319 DC = RD; 320 321 // Return the declaration context of the topmost class the inline method is 322 // declared in. 323 return DC; 324 } 325 326 if (isa<ObjCMethodDecl>(DC)) 327 return Context.getTranslationUnitDecl(); 328 329 return DC->getLexicalParent(); 330} 331 332void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 333 assert(getContainingDC(DC) == CurContext && 334 "The next DeclContext should be lexically contained in the current one."); 335 CurContext = DC; 336 S->setEntity(DC); 337} 338 339void Sema::PopDeclContext() { 340 assert(CurContext && "DeclContext imbalance!"); 341 342 CurContext = getContainingDC(CurContext); 343} 344 345/// EnterDeclaratorContext - Used when we must lookup names in the context 346/// of a declarator's nested name specifier. 347/// 348void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 349 // C++0x [basic.lookup.unqual]p13: 350 // A name used in the definition of a static data member of class 351 // X (after the qualified-id of the static member) is looked up as 352 // if the name was used in a member function of X. 353 // C++0x [basic.lookup.unqual]p14: 354 // If a variable member of a namespace is defined outside of the 355 // scope of its namespace then any name used in the definition of 356 // the variable member (after the declarator-id) is looked up as 357 // if the definition of the variable member occurred in its 358 // namespace. 359 // Both of these imply that we should push a scope whose context 360 // is the semantic context of the declaration. We can't use 361 // PushDeclContext here because that context is not necessarily 362 // lexically contained in the current context. Fortunately, 363 // the containing scope should have the appropriate information. 364 365 assert(!S->getEntity() && "scope already has entity"); 366 367#ifndef NDEBUG 368 Scope *Ancestor = S->getParent(); 369 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 370 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 371#endif 372 373 CurContext = DC; 374 S->setEntity(DC); 375} 376 377void Sema::ExitDeclaratorContext(Scope *S) { 378 assert(S->getEntity() == CurContext && "Context imbalance!"); 379 380 // Switch back to the lexical context. The safety of this is 381 // enforced by an assert in EnterDeclaratorContext. 382 Scope *Ancestor = S->getParent(); 383 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 384 CurContext = (DeclContext*) Ancestor->getEntity(); 385 386 // We don't need to do anything with the scope, which is going to 387 // disappear. 388} 389 390/// \brief Determine whether we allow overloading of the function 391/// PrevDecl with another declaration. 392/// 393/// This routine determines whether overloading is possible, not 394/// whether some new function is actually an overload. It will return 395/// true in C++ (where we can always provide overloads) or, as an 396/// extension, in C when the previous function is already an 397/// overloaded function declaration or has the "overloadable" 398/// attribute. 399static bool AllowOverloadingOfFunction(LookupResult &Previous, 400 ASTContext &Context) { 401 if (Context.getLangOptions().CPlusPlus) 402 return true; 403 404 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 405 return true; 406 407 return (Previous.getResultKind() == LookupResult::Found 408 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 409} 410 411/// Add this decl to the scope shadowed decl chains. 412void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 413 // Move up the scope chain until we find the nearest enclosing 414 // non-transparent context. The declaration will be introduced into this 415 // scope. 416 while (S->getEntity() && 417 ((DeclContext *)S->getEntity())->isTransparentContext()) 418 S = S->getParent(); 419 420 // Add scoped declarations into their context, so that they can be 421 // found later. Declarations without a context won't be inserted 422 // into any context. 423 if (AddToContext) 424 CurContext->addDecl(D); 425 426 // Out-of-line definitions shouldn't be pushed into scope in C++. 427 // Out-of-line variable and function definitions shouldn't even in C. 428 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 429 D->isOutOfLine()) 430 return; 431 432 // Template instantiations should also not be pushed into scope. 433 if (isa<FunctionDecl>(D) && 434 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 435 return; 436 437 // If this replaces anything in the current scope, 438 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 439 IEnd = IdResolver.end(); 440 for (; I != IEnd; ++I) { 441 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 442 S->RemoveDecl(DeclPtrTy::make(*I)); 443 IdResolver.RemoveDecl(*I); 444 445 // Should only need to replace one decl. 446 break; 447 } 448 } 449 450 S->AddDecl(DeclPtrTy::make(D)); 451 IdResolver.AddDecl(D); 452} 453 454bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 455 return IdResolver.isDeclInScope(D, Ctx, Context, S); 456} 457 458static bool isOutOfScopePreviousDeclaration(NamedDecl *, 459 DeclContext*, 460 ASTContext&); 461 462/// Filters out lookup results that don't fall within the given scope 463/// as determined by isDeclInScope. 464static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 465 DeclContext *Ctx, Scope *S, 466 bool ConsiderLinkage) { 467 LookupResult::Filter F = R.makeFilter(); 468 while (F.hasNext()) { 469 NamedDecl *D = F.next(); 470 471 if (SemaRef.isDeclInScope(D, Ctx, S)) 472 continue; 473 474 if (ConsiderLinkage && 475 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 476 continue; 477 478 F.erase(); 479 } 480 481 F.done(); 482} 483 484static bool isUsingDecl(NamedDecl *D) { 485 return isa<UsingShadowDecl>(D) || 486 isa<UnresolvedUsingTypenameDecl>(D) || 487 isa<UnresolvedUsingValueDecl>(D); 488} 489 490/// Removes using shadow declarations from the lookup results. 491static void RemoveUsingDecls(LookupResult &R) { 492 LookupResult::Filter F = R.makeFilter(); 493 while (F.hasNext()) 494 if (isUsingDecl(F.next())) 495 F.erase(); 496 497 F.done(); 498} 499 500static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 501 if (D->isInvalidDecl()) 502 return false; 503 504 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 505 return false; 506 507 // White-list anything that isn't a local variable. 508 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 509 !D->getDeclContext()->isFunctionOrMethod()) 510 return false; 511 512 // Types of valid local variables should be complete, so this should succeed. 513 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 514 515 // White-list anything with an __attribute__((unused)) type. 516 QualType Ty = VD->getType(); 517 518 // Only look at the outermost level of typedef. 519 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 520 if (TT->getDecl()->hasAttr<UnusedAttr>()) 521 return false; 522 } 523 524 if (const TagType *TT = Ty->getAs<TagType>()) { 525 const TagDecl *Tag = TT->getDecl(); 526 if (Tag->hasAttr<UnusedAttr>()) 527 return false; 528 529 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 530 if (!RD->hasTrivialConstructor()) 531 return false; 532 if (!RD->hasTrivialDestructor()) 533 return false; 534 } 535 } 536 537 // TODO: __attribute__((unused)) templates? 538 } 539 540 return true; 541} 542 543void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 544 if (S->decl_empty()) return; 545 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 546 "Scope shouldn't contain decls!"); 547 548 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 549 I != E; ++I) { 550 Decl *TmpD = (*I).getAs<Decl>(); 551 assert(TmpD && "This decl didn't get pushed??"); 552 553 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 554 NamedDecl *D = cast<NamedDecl>(TmpD); 555 556 if (!D->getDeclName()) continue; 557 558 // Diagnose unused variables in this scope. 559 if (ShouldDiagnoseUnusedDecl(D) && 560 S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 561 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 562 563 // Remove this name from our lexical scope. 564 IdResolver.RemoveDecl(D); 565 } 566} 567 568/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 569/// return 0 if one not found. 570/// 571/// \param Id the name of the Objective-C class we're looking for. If 572/// typo-correction fixes this name, the Id will be updated 573/// to the fixed name. 574/// 575/// \param RecoverLoc if provided, this routine will attempt to 576/// recover from a typo in the name of an existing Objective-C class 577/// and, if successful, will return the lookup that results from 578/// typo-correction. 579ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 580 SourceLocation RecoverLoc) { 581 // The third "scope" argument is 0 since we aren't enabling lazy built-in 582 // creation from this context. 583 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 584 585 if (!IDecl && !RecoverLoc.isInvalid()) { 586 // Perform typo correction at the given location, but only if we 587 // find an Objective-C class name. 588 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 589 if (CorrectTypo(R, TUScope, 0) && 590 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 591 Diag(RecoverLoc, diag::err_undef_interface_suggest) 592 << Id << IDecl->getDeclName() 593 << CodeModificationHint::CreateReplacement(RecoverLoc, 594 IDecl->getNameAsString()); 595 Diag(IDecl->getLocation(), diag::note_previous_decl) 596 << IDecl->getDeclName(); 597 598 Id = IDecl->getIdentifier(); 599 } 600 } 601 602 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 603} 604 605/// getNonFieldDeclScope - Retrieves the innermost scope, starting 606/// from S, where a non-field would be declared. This routine copes 607/// with the difference between C and C++ scoping rules in structs and 608/// unions. For example, the following code is well-formed in C but 609/// ill-formed in C++: 610/// @code 611/// struct S6 { 612/// enum { BAR } e; 613/// }; 614/// 615/// void test_S6() { 616/// struct S6 a; 617/// a.e = BAR; 618/// } 619/// @endcode 620/// For the declaration of BAR, this routine will return a different 621/// scope. The scope S will be the scope of the unnamed enumeration 622/// within S6. In C++, this routine will return the scope associated 623/// with S6, because the enumeration's scope is a transparent 624/// context but structures can contain non-field names. In C, this 625/// routine will return the translation unit scope, since the 626/// enumeration's scope is a transparent context and structures cannot 627/// contain non-field names. 628Scope *Sema::getNonFieldDeclScope(Scope *S) { 629 while (((S->getFlags() & Scope::DeclScope) == 0) || 630 (S->getEntity() && 631 ((DeclContext *)S->getEntity())->isTransparentContext()) || 632 (S->isClassScope() && !getLangOptions().CPlusPlus)) 633 S = S->getParent(); 634 return S; 635} 636 637void Sema::InitBuiltinVaListType() { 638 if (!Context.getBuiltinVaListType().isNull()) 639 return; 640 641 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 642 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 643 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 644 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 645} 646 647/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 648/// file scope. lazily create a decl for it. ForRedeclaration is true 649/// if we're creating this built-in in anticipation of redeclaring the 650/// built-in. 651NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 652 Scope *S, bool ForRedeclaration, 653 SourceLocation Loc) { 654 Builtin::ID BID = (Builtin::ID)bid; 655 656 if (Context.BuiltinInfo.hasVAListUse(BID)) 657 InitBuiltinVaListType(); 658 659 ASTContext::GetBuiltinTypeError Error; 660 QualType R = Context.GetBuiltinType(BID, Error); 661 switch (Error) { 662 case ASTContext::GE_None: 663 // Okay 664 break; 665 666 case ASTContext::GE_Missing_stdio: 667 if (ForRedeclaration) 668 Diag(Loc, diag::err_implicit_decl_requires_stdio) 669 << Context.BuiltinInfo.GetName(BID); 670 return 0; 671 672 case ASTContext::GE_Missing_setjmp: 673 if (ForRedeclaration) 674 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 675 << Context.BuiltinInfo.GetName(BID); 676 return 0; 677 } 678 679 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 680 Diag(Loc, diag::ext_implicit_lib_function_decl) 681 << Context.BuiltinInfo.GetName(BID) 682 << R; 683 if (Context.BuiltinInfo.getHeaderName(BID) && 684 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 685 != Diagnostic::Ignored) 686 Diag(Loc, diag::note_please_include_header) 687 << Context.BuiltinInfo.getHeaderName(BID) 688 << Context.BuiltinInfo.GetName(BID); 689 } 690 691 FunctionDecl *New = FunctionDecl::Create(Context, 692 Context.getTranslationUnitDecl(), 693 Loc, II, R, /*TInfo=*/0, 694 FunctionDecl::Extern, false, 695 /*hasPrototype=*/true); 696 New->setImplicit(); 697 698 // Create Decl objects for each parameter, adding them to the 699 // FunctionDecl. 700 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 701 llvm::SmallVector<ParmVarDecl*, 16> Params; 702 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 703 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 704 FT->getArgType(i), /*TInfo=*/0, 705 VarDecl::None, 0)); 706 New->setParams(Params.data(), Params.size()); 707 } 708 709 AddKnownFunctionAttributes(New); 710 711 // TUScope is the translation-unit scope to insert this function into. 712 // FIXME: This is hideous. We need to teach PushOnScopeChains to 713 // relate Scopes to DeclContexts, and probably eliminate CurContext 714 // entirely, but we're not there yet. 715 DeclContext *SavedContext = CurContext; 716 CurContext = Context.getTranslationUnitDecl(); 717 PushOnScopeChains(New, TUScope); 718 CurContext = SavedContext; 719 return New; 720} 721 722/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 723/// same name and scope as a previous declaration 'Old'. Figure out 724/// how to resolve this situation, merging decls or emitting 725/// diagnostics as appropriate. If there was an error, set New to be invalid. 726/// 727void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 728 // If the new decl is known invalid already, don't bother doing any 729 // merging checks. 730 if (New->isInvalidDecl()) return; 731 732 // Allow multiple definitions for ObjC built-in typedefs. 733 // FIXME: Verify the underlying types are equivalent! 734 if (getLangOptions().ObjC1) { 735 const IdentifierInfo *TypeID = New->getIdentifier(); 736 switch (TypeID->getLength()) { 737 default: break; 738 case 2: 739 if (!TypeID->isStr("id")) 740 break; 741 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 742 // Install the built-in type for 'id', ignoring the current definition. 743 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 744 return; 745 case 5: 746 if (!TypeID->isStr("Class")) 747 break; 748 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 749 // Install the built-in type for 'Class', ignoring the current definition. 750 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 751 return; 752 case 3: 753 if (!TypeID->isStr("SEL")) 754 break; 755 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 756 // Install the built-in type for 'SEL', ignoring the current definition. 757 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 758 return; 759 case 8: 760 if (!TypeID->isStr("Protocol")) 761 break; 762 Context.setObjCProtoType(New->getUnderlyingType()); 763 return; 764 } 765 // Fall through - the typedef name was not a builtin type. 766 } 767 768 // Verify the old decl was also a type. 769 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 770 if (!Old) { 771 Diag(New->getLocation(), diag::err_redefinition_different_kind) 772 << New->getDeclName(); 773 774 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 775 if (OldD->getLocation().isValid()) 776 Diag(OldD->getLocation(), diag::note_previous_definition); 777 778 return New->setInvalidDecl(); 779 } 780 781 // If the old declaration is invalid, just give up here. 782 if (Old->isInvalidDecl()) 783 return New->setInvalidDecl(); 784 785 // Determine the "old" type we'll use for checking and diagnostics. 786 QualType OldType; 787 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 788 OldType = OldTypedef->getUnderlyingType(); 789 else 790 OldType = Context.getTypeDeclType(Old); 791 792 // If the typedef types are not identical, reject them in all languages and 793 // with any extensions enabled. 794 795 if (OldType != New->getUnderlyingType() && 796 Context.getCanonicalType(OldType) != 797 Context.getCanonicalType(New->getUnderlyingType())) { 798 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 799 << New->getUnderlyingType() << OldType; 800 if (Old->getLocation().isValid()) 801 Diag(Old->getLocation(), diag::note_previous_definition); 802 return New->setInvalidDecl(); 803 } 804 805 // The types match. Link up the redeclaration chain if the old 806 // declaration was a typedef. 807 // FIXME: this is a potential source of wierdness if the type 808 // spellings don't match exactly. 809 if (isa<TypedefDecl>(Old)) 810 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 811 812 if (getLangOptions().Microsoft) 813 return; 814 815 if (getLangOptions().CPlusPlus) { 816 // C++ [dcl.typedef]p2: 817 // In a given non-class scope, a typedef specifier can be used to 818 // redefine the name of any type declared in that scope to refer 819 // to the type to which it already refers. 820 if (!isa<CXXRecordDecl>(CurContext)) 821 return; 822 823 // C++0x [dcl.typedef]p4: 824 // In a given class scope, a typedef specifier can be used to redefine 825 // any class-name declared in that scope that is not also a typedef-name 826 // to refer to the type to which it already refers. 827 // 828 // This wording came in via DR424, which was a correction to the 829 // wording in DR56, which accidentally banned code like: 830 // 831 // struct S { 832 // typedef struct A { } A; 833 // }; 834 // 835 // in the C++03 standard. We implement the C++0x semantics, which 836 // allow the above but disallow 837 // 838 // struct S { 839 // typedef int I; 840 // typedef int I; 841 // }; 842 // 843 // since that was the intent of DR56. 844 if (!isa<TypedefDecl >(Old)) 845 return; 846 847 Diag(New->getLocation(), diag::err_redefinition) 848 << New->getDeclName(); 849 Diag(Old->getLocation(), diag::note_previous_definition); 850 return New->setInvalidDecl(); 851 } 852 853 // If we have a redefinition of a typedef in C, emit a warning. This warning 854 // is normally mapped to an error, but can be controlled with 855 // -Wtypedef-redefinition. If either the original or the redefinition is 856 // in a system header, don't emit this for compatibility with GCC. 857 if (getDiagnostics().getSuppressSystemWarnings() && 858 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 859 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 860 return; 861 862 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 863 << New->getDeclName(); 864 Diag(Old->getLocation(), diag::note_previous_definition); 865 return; 866} 867 868/// DeclhasAttr - returns true if decl Declaration already has the target 869/// attribute. 870static bool 871DeclHasAttr(const Decl *decl, const Attr *target) { 872 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 873 if (attr->getKind() == target->getKind()) 874 return true; 875 876 return false; 877} 878 879/// MergeAttributes - append attributes from the Old decl to the New one. 880static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 881 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 882 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 883 Attr *NewAttr = attr->clone(C); 884 NewAttr->setInherited(true); 885 New->addAttr(NewAttr); 886 } 887 } 888} 889 890/// Used in MergeFunctionDecl to keep track of function parameters in 891/// C. 892struct GNUCompatibleParamWarning { 893 ParmVarDecl *OldParm; 894 ParmVarDecl *NewParm; 895 QualType PromotedType; 896}; 897 898 899/// getSpecialMember - get the special member enum for a method. 900static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 901 const CXXMethodDecl *MD) { 902 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 903 if (Ctor->isDefaultConstructor()) 904 return Sema::CXXDefaultConstructor; 905 if (Ctor->isCopyConstructor()) 906 return Sema::CXXCopyConstructor; 907 } 908 909 if (isa<CXXDestructorDecl>(MD)) 910 return Sema::CXXDestructor; 911 912 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 913 return Sema::CXXCopyAssignment; 914} 915 916/// canREdefineFunction - checks if a function can be redefined. Currently, 917/// only extern inline functions can be redefined, and even then only in 918/// GNU89 mode. 919static bool canRedefineFunction(const FunctionDecl *FD, 920 const LangOptions& LangOpts) { 921 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 922 FD->isInlineSpecified() && 923 FD->getStorageClass() == FunctionDecl::Extern); 924} 925 926/// MergeFunctionDecl - We just parsed a function 'New' from 927/// declarator D which has the same name and scope as a previous 928/// declaration 'Old'. Figure out how to resolve this situation, 929/// merging decls or emitting diagnostics as appropriate. 930/// 931/// In C++, New and Old must be declarations that are not 932/// overloaded. Use IsOverload to determine whether New and Old are 933/// overloaded, and to select the Old declaration that New should be 934/// merged with. 935/// 936/// Returns true if there was an error, false otherwise. 937bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 938 // Verify the old decl was also a function. 939 FunctionDecl *Old = 0; 940 if (FunctionTemplateDecl *OldFunctionTemplate 941 = dyn_cast<FunctionTemplateDecl>(OldD)) 942 Old = OldFunctionTemplate->getTemplatedDecl(); 943 else 944 Old = dyn_cast<FunctionDecl>(OldD); 945 if (!Old) { 946 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 947 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 948 Diag(Shadow->getTargetDecl()->getLocation(), 949 diag::note_using_decl_target); 950 Diag(Shadow->getUsingDecl()->getLocation(), 951 diag::note_using_decl) << 0; 952 return true; 953 } 954 955 Diag(New->getLocation(), diag::err_redefinition_different_kind) 956 << New->getDeclName(); 957 Diag(OldD->getLocation(), diag::note_previous_definition); 958 return true; 959 } 960 961 // Determine whether the previous declaration was a definition, 962 // implicit declaration, or a declaration. 963 diag::kind PrevDiag; 964 if (Old->isThisDeclarationADefinition()) 965 PrevDiag = diag::note_previous_definition; 966 else if (Old->isImplicit()) 967 PrevDiag = diag::note_previous_implicit_declaration; 968 else 969 PrevDiag = diag::note_previous_declaration; 970 971 QualType OldQType = Context.getCanonicalType(Old->getType()); 972 QualType NewQType = Context.getCanonicalType(New->getType()); 973 974 // Don't complain about this if we're in GNU89 mode and the old function 975 // is an extern inline function. 976 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 977 New->getStorageClass() == FunctionDecl::Static && 978 Old->getStorageClass() != FunctionDecl::Static && 979 !canRedefineFunction(Old, getLangOptions())) { 980 Diag(New->getLocation(), diag::err_static_non_static) 981 << New; 982 Diag(Old->getLocation(), PrevDiag); 983 return true; 984 } 985 986 // If a function is first declared with a calling convention, but is 987 // later declared or defined without one, the second decl assumes the 988 // calling convention of the first. 989 // 990 // For the new decl, we have to look at the NON-canonical type to tell the 991 // difference between a function that really doesn't have a calling 992 // convention and one that is declared cdecl. That's because in 993 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 994 // because it is the default calling convention. 995 // 996 // Note also that we DO NOT return at this point, because we still have 997 // other tests to run. 998 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 999 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1000 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1001 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1002 if (OldTypeInfo.getCC() != CC_Default && 1003 NewTypeInfo.getCC() == CC_Default) { 1004 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1005 New->setType(NewQType); 1006 NewQType = Context.getCanonicalType(NewQType); 1007 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1008 NewTypeInfo.getCC())) { 1009 // Calling conventions really aren't compatible, so complain. 1010 Diag(New->getLocation(), diag::err_cconv_change) 1011 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1012 << (OldTypeInfo.getCC() == CC_Default) 1013 << (OldTypeInfo.getCC() == CC_Default ? "" : 1014 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1015 Diag(Old->getLocation(), diag::note_previous_declaration); 1016 return true; 1017 } 1018 1019 // FIXME: diagnose the other way around? 1020 if (OldType->getNoReturnAttr() && 1021 !NewType->getNoReturnAttr()) { 1022 NewQType = Context.getNoReturnType(NewQType); 1023 New->setType(NewQType); 1024 assert(NewQType.isCanonical()); 1025 } 1026 1027 if (getLangOptions().CPlusPlus) { 1028 // (C++98 13.1p2): 1029 // Certain function declarations cannot be overloaded: 1030 // -- Function declarations that differ only in the return type 1031 // cannot be overloaded. 1032 QualType OldReturnType 1033 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1034 QualType NewReturnType 1035 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1036 if (OldReturnType != NewReturnType) { 1037 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1038 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1039 return true; 1040 } 1041 1042 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1043 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1044 if (OldMethod && NewMethod) { 1045 if (!NewMethod->getFriendObjectKind() && 1046 NewMethod->getLexicalDeclContext()->isRecord()) { 1047 // -- Member function declarations with the same name and the 1048 // same parameter types cannot be overloaded if any of them 1049 // is a static member function declaration. 1050 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1051 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1052 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1053 return true; 1054 } 1055 1056 // C++ [class.mem]p1: 1057 // [...] A member shall not be declared twice in the 1058 // member-specification, except that a nested class or member 1059 // class template can be declared and then later defined. 1060 unsigned NewDiag; 1061 if (isa<CXXConstructorDecl>(OldMethod)) 1062 NewDiag = diag::err_constructor_redeclared; 1063 else if (isa<CXXDestructorDecl>(NewMethod)) 1064 NewDiag = diag::err_destructor_redeclared; 1065 else if (isa<CXXConversionDecl>(NewMethod)) 1066 NewDiag = diag::err_conv_function_redeclared; 1067 else 1068 NewDiag = diag::err_member_redeclared; 1069 1070 Diag(New->getLocation(), NewDiag); 1071 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1072 } else { 1073 if (OldMethod->isImplicit()) { 1074 Diag(NewMethod->getLocation(), 1075 diag::err_definition_of_implicitly_declared_member) 1076 << New << getSpecialMember(Context, OldMethod); 1077 1078 Diag(OldMethod->getLocation(), 1079 diag::note_previous_implicit_declaration); 1080 return true; 1081 } 1082 } 1083 } 1084 1085 // (C++98 8.3.5p3): 1086 // All declarations for a function shall agree exactly in both the 1087 // return type and the parameter-type-list. 1088 // attributes should be ignored when comparing. 1089 if (Context.getNoReturnType(OldQType, false) == 1090 Context.getNoReturnType(NewQType, false)) 1091 return MergeCompatibleFunctionDecls(New, Old); 1092 1093 // Fall through for conflicting redeclarations and redefinitions. 1094 } 1095 1096 // C: Function types need to be compatible, not identical. This handles 1097 // duplicate function decls like "void f(int); void f(enum X);" properly. 1098 if (!getLangOptions().CPlusPlus && 1099 Context.typesAreCompatible(OldQType, NewQType)) { 1100 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1101 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1102 const FunctionProtoType *OldProto = 0; 1103 if (isa<FunctionNoProtoType>(NewFuncType) && 1104 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1105 // The old declaration provided a function prototype, but the 1106 // new declaration does not. Merge in the prototype. 1107 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1108 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1109 OldProto->arg_type_end()); 1110 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1111 ParamTypes.data(), ParamTypes.size(), 1112 OldProto->isVariadic(), 1113 OldProto->getTypeQuals(), 1114 false, false, 0, 0, 1115 OldProto->getExtInfo()); 1116 New->setType(NewQType); 1117 New->setHasInheritedPrototype(); 1118 1119 // Synthesize a parameter for each argument type. 1120 llvm::SmallVector<ParmVarDecl*, 16> Params; 1121 for (FunctionProtoType::arg_type_iterator 1122 ParamType = OldProto->arg_type_begin(), 1123 ParamEnd = OldProto->arg_type_end(); 1124 ParamType != ParamEnd; ++ParamType) { 1125 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1126 SourceLocation(), 0, 1127 *ParamType, /*TInfo=*/0, 1128 VarDecl::None, 0); 1129 Param->setImplicit(); 1130 Params.push_back(Param); 1131 } 1132 1133 New->setParams(Params.data(), Params.size()); 1134 } 1135 1136 return MergeCompatibleFunctionDecls(New, Old); 1137 } 1138 1139 // GNU C permits a K&R definition to follow a prototype declaration 1140 // if the declared types of the parameters in the K&R definition 1141 // match the types in the prototype declaration, even when the 1142 // promoted types of the parameters from the K&R definition differ 1143 // from the types in the prototype. GCC then keeps the types from 1144 // the prototype. 1145 // 1146 // If a variadic prototype is followed by a non-variadic K&R definition, 1147 // the K&R definition becomes variadic. This is sort of an edge case, but 1148 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1149 // C99 6.9.1p8. 1150 if (!getLangOptions().CPlusPlus && 1151 Old->hasPrototype() && !New->hasPrototype() && 1152 New->getType()->getAs<FunctionProtoType>() && 1153 Old->getNumParams() == New->getNumParams()) { 1154 llvm::SmallVector<QualType, 16> ArgTypes; 1155 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1156 const FunctionProtoType *OldProto 1157 = Old->getType()->getAs<FunctionProtoType>(); 1158 const FunctionProtoType *NewProto 1159 = New->getType()->getAs<FunctionProtoType>(); 1160 1161 // Determine whether this is the GNU C extension. 1162 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1163 NewProto->getResultType()); 1164 bool LooseCompatible = !MergedReturn.isNull(); 1165 for (unsigned Idx = 0, End = Old->getNumParams(); 1166 LooseCompatible && Idx != End; ++Idx) { 1167 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1168 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1169 if (Context.typesAreCompatible(OldParm->getType(), 1170 NewProto->getArgType(Idx))) { 1171 ArgTypes.push_back(NewParm->getType()); 1172 } else if (Context.typesAreCompatible(OldParm->getType(), 1173 NewParm->getType())) { 1174 GNUCompatibleParamWarning Warn 1175 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1176 Warnings.push_back(Warn); 1177 ArgTypes.push_back(NewParm->getType()); 1178 } else 1179 LooseCompatible = false; 1180 } 1181 1182 if (LooseCompatible) { 1183 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1184 Diag(Warnings[Warn].NewParm->getLocation(), 1185 diag::ext_param_promoted_not_compatible_with_prototype) 1186 << Warnings[Warn].PromotedType 1187 << Warnings[Warn].OldParm->getType(); 1188 Diag(Warnings[Warn].OldParm->getLocation(), 1189 diag::note_previous_declaration); 1190 } 1191 1192 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1193 ArgTypes.size(), 1194 OldProto->isVariadic(), 0, 1195 false, false, 0, 0, 1196 OldProto->getExtInfo())); 1197 return MergeCompatibleFunctionDecls(New, Old); 1198 } 1199 1200 // Fall through to diagnose conflicting types. 1201 } 1202 1203 // A function that has already been declared has been redeclared or defined 1204 // with a different type- show appropriate diagnostic 1205 if (unsigned BuiltinID = Old->getBuiltinID()) { 1206 // The user has declared a builtin function with an incompatible 1207 // signature. 1208 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1209 // The function the user is redeclaring is a library-defined 1210 // function like 'malloc' or 'printf'. Warn about the 1211 // redeclaration, then pretend that we don't know about this 1212 // library built-in. 1213 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1214 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1215 << Old << Old->getType(); 1216 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1217 Old->setInvalidDecl(); 1218 return false; 1219 } 1220 1221 PrevDiag = diag::note_previous_builtin_declaration; 1222 } 1223 1224 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1225 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1226 return true; 1227} 1228 1229/// \brief Completes the merge of two function declarations that are 1230/// known to be compatible. 1231/// 1232/// This routine handles the merging of attributes and other 1233/// properties of function declarations form the old declaration to 1234/// the new declaration, once we know that New is in fact a 1235/// redeclaration of Old. 1236/// 1237/// \returns false 1238bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1239 // Merge the attributes 1240 MergeAttributes(New, Old, Context); 1241 1242 // Merge the storage class. 1243 if (Old->getStorageClass() != FunctionDecl::Extern && 1244 Old->getStorageClass() != FunctionDecl::None) 1245 New->setStorageClass(Old->getStorageClass()); 1246 1247 // Merge "pure" flag. 1248 if (Old->isPure()) 1249 New->setPure(); 1250 1251 // Merge the "deleted" flag. 1252 if (Old->isDeleted()) 1253 New->setDeleted(); 1254 1255 if (getLangOptions().CPlusPlus) 1256 return MergeCXXFunctionDecl(New, Old); 1257 1258 return false; 1259} 1260 1261/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1262/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1263/// situation, merging decls or emitting diagnostics as appropriate. 1264/// 1265/// Tentative definition rules (C99 6.9.2p2) are checked by 1266/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1267/// definitions here, since the initializer hasn't been attached. 1268/// 1269void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1270 // If the new decl is already invalid, don't do any other checking. 1271 if (New->isInvalidDecl()) 1272 return; 1273 1274 // Verify the old decl was also a variable. 1275 VarDecl *Old = 0; 1276 if (!Previous.isSingleResult() || 1277 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1278 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1279 << New->getDeclName(); 1280 Diag(Previous.getRepresentativeDecl()->getLocation(), 1281 diag::note_previous_definition); 1282 return New->setInvalidDecl(); 1283 } 1284 1285 MergeAttributes(New, Old, Context); 1286 1287 // Merge the types 1288 QualType MergedT; 1289 if (getLangOptions().CPlusPlus) { 1290 if (Context.hasSameType(New->getType(), Old->getType())) 1291 MergedT = New->getType(); 1292 // C++ [basic.link]p10: 1293 // [...] the types specified by all declarations referring to a given 1294 // object or function shall be identical, except that declarations for an 1295 // array object can specify array types that differ by the presence or 1296 // absence of a major array bound (8.3.4). 1297 else if (Old->getType()->isIncompleteArrayType() && 1298 New->getType()->isArrayType()) { 1299 CanQual<ArrayType> OldArray 1300 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1301 CanQual<ArrayType> NewArray 1302 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1303 if (OldArray->getElementType() == NewArray->getElementType()) 1304 MergedT = New->getType(); 1305 } else if (Old->getType()->isArrayType() && 1306 New->getType()->isIncompleteArrayType()) { 1307 CanQual<ArrayType> OldArray 1308 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1309 CanQual<ArrayType> NewArray 1310 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1311 if (OldArray->getElementType() == NewArray->getElementType()) 1312 MergedT = Old->getType(); 1313 } 1314 } else { 1315 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1316 } 1317 if (MergedT.isNull()) { 1318 Diag(New->getLocation(), diag::err_redefinition_different_type) 1319 << New->getDeclName(); 1320 Diag(Old->getLocation(), diag::note_previous_definition); 1321 return New->setInvalidDecl(); 1322 } 1323 New->setType(MergedT); 1324 1325 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1326 if (New->getStorageClass() == VarDecl::Static && 1327 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1328 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1329 Diag(Old->getLocation(), diag::note_previous_definition); 1330 return New->setInvalidDecl(); 1331 } 1332 // C99 6.2.2p4: 1333 // For an identifier declared with the storage-class specifier 1334 // extern in a scope in which a prior declaration of that 1335 // identifier is visible,23) if the prior declaration specifies 1336 // internal or external linkage, the linkage of the identifier at 1337 // the later declaration is the same as the linkage specified at 1338 // the prior declaration. If no prior declaration is visible, or 1339 // if the prior declaration specifies no linkage, then the 1340 // identifier has external linkage. 1341 if (New->hasExternalStorage() && Old->hasLinkage()) 1342 /* Okay */; 1343 else if (New->getStorageClass() != VarDecl::Static && 1344 Old->getStorageClass() == VarDecl::Static) { 1345 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1346 Diag(Old->getLocation(), diag::note_previous_definition); 1347 return New->setInvalidDecl(); 1348 } 1349 1350 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1351 1352 // FIXME: The test for external storage here seems wrong? We still 1353 // need to check for mismatches. 1354 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1355 // Don't complain about out-of-line definitions of static members. 1356 !(Old->getLexicalDeclContext()->isRecord() && 1357 !New->getLexicalDeclContext()->isRecord())) { 1358 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1359 Diag(Old->getLocation(), diag::note_previous_definition); 1360 return New->setInvalidDecl(); 1361 } 1362 1363 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1364 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1365 Diag(Old->getLocation(), diag::note_previous_definition); 1366 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1367 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1368 Diag(Old->getLocation(), diag::note_previous_definition); 1369 } 1370 1371 // C++ doesn't have tentative definitions, so go right ahead and check here. 1372 const VarDecl *Def; 1373 if (getLangOptions().CPlusPlus && 1374 New->isThisDeclarationADefinition() == VarDecl::Definition && 1375 (Def = Old->getDefinition())) { 1376 Diag(New->getLocation(), diag::err_redefinition) 1377 << New->getDeclName(); 1378 Diag(Def->getLocation(), diag::note_previous_definition); 1379 New->setInvalidDecl(); 1380 return; 1381 } 1382 1383 // Keep a chain of previous declarations. 1384 New->setPreviousDeclaration(Old); 1385 1386 // Inherit access appropriately. 1387 New->setAccess(Old->getAccess()); 1388} 1389 1390/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1391/// no declarator (e.g. "struct foo;") is parsed. 1392Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1393 // FIXME: Error on auto/register at file scope 1394 // FIXME: Error on inline/virtual/explicit 1395 // FIXME: Warn on useless __thread 1396 // FIXME: Warn on useless const/volatile 1397 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1398 // FIXME: Warn on useless attributes 1399 Decl *TagD = 0; 1400 TagDecl *Tag = 0; 1401 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1402 DS.getTypeSpecType() == DeclSpec::TST_struct || 1403 DS.getTypeSpecType() == DeclSpec::TST_union || 1404 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1405 TagD = static_cast<Decl *>(DS.getTypeRep()); 1406 1407 if (!TagD) // We probably had an error 1408 return DeclPtrTy(); 1409 1410 // Note that the above type specs guarantee that the 1411 // type rep is a Decl, whereas in many of the others 1412 // it's a Type. 1413 Tag = dyn_cast<TagDecl>(TagD); 1414 } 1415 1416 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1417 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1418 // or incomplete types shall not be restrict-qualified." 1419 if (TypeQuals & DeclSpec::TQ_restrict) 1420 Diag(DS.getRestrictSpecLoc(), 1421 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1422 << DS.getSourceRange(); 1423 } 1424 1425 if (DS.isFriendSpecified()) { 1426 // If we're dealing with a class template decl, assume that the 1427 // template routines are handling it. 1428 if (TagD && isa<ClassTemplateDecl>(TagD)) 1429 return DeclPtrTy(); 1430 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1431 } 1432 1433 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1434 // If there are attributes in the DeclSpec, apply them to the record. 1435 if (const AttributeList *AL = DS.getAttributes()) 1436 ProcessDeclAttributeList(S, Record, AL); 1437 1438 if (!Record->getDeclName() && Record->isDefinition() && 1439 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1440 if (getLangOptions().CPlusPlus || 1441 Record->getDeclContext()->isRecord()) 1442 return BuildAnonymousStructOrUnion(S, DS, Record); 1443 1444 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1445 << DS.getSourceRange(); 1446 } 1447 1448 // Microsoft allows unnamed struct/union fields. Don't complain 1449 // about them. 1450 // FIXME: Should we support Microsoft's extensions in this area? 1451 if (Record->getDeclName() && getLangOptions().Microsoft) 1452 return DeclPtrTy::make(Tag); 1453 } 1454 1455 if (!DS.isMissingDeclaratorOk() && 1456 DS.getTypeSpecType() != DeclSpec::TST_error) { 1457 // Warn about typedefs of enums without names, since this is an 1458 // extension in both Microsoft an GNU. 1459 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1460 Tag && isa<EnumDecl>(Tag)) { 1461 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1462 << DS.getSourceRange(); 1463 return DeclPtrTy::make(Tag); 1464 } 1465 1466 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1467 << DS.getSourceRange(); 1468 return DeclPtrTy(); 1469 } 1470 1471 return DeclPtrTy::make(Tag); 1472} 1473 1474/// We are trying to inject an anonymous member into the given scope; 1475/// check if there's an existing declaration that can't be overloaded. 1476/// 1477/// \return true if this is a forbidden redeclaration 1478static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1479 Scope *S, 1480 DeclContext *Owner, 1481 DeclarationName Name, 1482 SourceLocation NameLoc, 1483 unsigned diagnostic) { 1484 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1485 Sema::ForRedeclaration); 1486 if (!SemaRef.LookupName(R, S)) return false; 1487 1488 if (R.getAsSingle<TagDecl>()) 1489 return false; 1490 1491 // Pick a representative declaration. 1492 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1493 if (PrevDecl && Owner->isRecord()) { 1494 RecordDecl *Record = cast<RecordDecl>(Owner); 1495 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1496 return false; 1497 } 1498 1499 SemaRef.Diag(NameLoc, diagnostic) << Name; 1500 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1501 1502 return true; 1503} 1504 1505/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1506/// anonymous struct or union AnonRecord into the owning context Owner 1507/// and scope S. This routine will be invoked just after we realize 1508/// that an unnamed union or struct is actually an anonymous union or 1509/// struct, e.g., 1510/// 1511/// @code 1512/// union { 1513/// int i; 1514/// float f; 1515/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1516/// // f into the surrounding scope.x 1517/// @endcode 1518/// 1519/// This routine is recursive, injecting the names of nested anonymous 1520/// structs/unions into the owning context and scope as well. 1521bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1522 RecordDecl *AnonRecord) { 1523 unsigned diagKind 1524 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1525 : diag::err_anonymous_struct_member_redecl; 1526 1527 bool Invalid = false; 1528 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1529 FEnd = AnonRecord->field_end(); 1530 F != FEnd; ++F) { 1531 if ((*F)->getDeclName()) { 1532 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1533 (*F)->getLocation(), diagKind)) { 1534 // C++ [class.union]p2: 1535 // The names of the members of an anonymous union shall be 1536 // distinct from the names of any other entity in the 1537 // scope in which the anonymous union is declared. 1538 Invalid = true; 1539 } else { 1540 // C++ [class.union]p2: 1541 // For the purpose of name lookup, after the anonymous union 1542 // definition, the members of the anonymous union are 1543 // considered to have been defined in the scope in which the 1544 // anonymous union is declared. 1545 Owner->makeDeclVisibleInContext(*F); 1546 S->AddDecl(DeclPtrTy::make(*F)); 1547 IdResolver.AddDecl(*F); 1548 } 1549 } else if (const RecordType *InnerRecordType 1550 = (*F)->getType()->getAs<RecordType>()) { 1551 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1552 if (InnerRecord->isAnonymousStructOrUnion()) 1553 Invalid = Invalid || 1554 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1555 } 1556 } 1557 1558 return Invalid; 1559} 1560 1561/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1562/// anonymous structure or union. Anonymous unions are a C++ feature 1563/// (C++ [class.union]) and a GNU C extension; anonymous structures 1564/// are a GNU C and GNU C++ extension. 1565Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1566 RecordDecl *Record) { 1567 DeclContext *Owner = Record->getDeclContext(); 1568 1569 // Diagnose whether this anonymous struct/union is an extension. 1570 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1571 Diag(Record->getLocation(), diag::ext_anonymous_union); 1572 else if (!Record->isUnion()) 1573 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1574 1575 // C and C++ require different kinds of checks for anonymous 1576 // structs/unions. 1577 bool Invalid = false; 1578 if (getLangOptions().CPlusPlus) { 1579 const char* PrevSpec = 0; 1580 unsigned DiagID; 1581 // C++ [class.union]p3: 1582 // Anonymous unions declared in a named namespace or in the 1583 // global namespace shall be declared static. 1584 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1585 (isa<TranslationUnitDecl>(Owner) || 1586 (isa<NamespaceDecl>(Owner) && 1587 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1588 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1589 Invalid = true; 1590 1591 // Recover by adding 'static'. 1592 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1593 PrevSpec, DiagID); 1594 } 1595 // C++ [class.union]p3: 1596 // A storage class is not allowed in a declaration of an 1597 // anonymous union in a class scope. 1598 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1599 isa<RecordDecl>(Owner)) { 1600 Diag(DS.getStorageClassSpecLoc(), 1601 diag::err_anonymous_union_with_storage_spec); 1602 Invalid = true; 1603 1604 // Recover by removing the storage specifier. 1605 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1606 PrevSpec, DiagID); 1607 } 1608 1609 // C++ [class.union]p2: 1610 // The member-specification of an anonymous union shall only 1611 // define non-static data members. [Note: nested types and 1612 // functions cannot be declared within an anonymous union. ] 1613 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1614 MemEnd = Record->decls_end(); 1615 Mem != MemEnd; ++Mem) { 1616 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1617 // C++ [class.union]p3: 1618 // An anonymous union shall not have private or protected 1619 // members (clause 11). 1620 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1621 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1622 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1623 Invalid = true; 1624 } 1625 } else if ((*Mem)->isImplicit()) { 1626 // Any implicit members are fine. 1627 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1628 // This is a type that showed up in an 1629 // elaborated-type-specifier inside the anonymous struct or 1630 // union, but which actually declares a type outside of the 1631 // anonymous struct or union. It's okay. 1632 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1633 if (!MemRecord->isAnonymousStructOrUnion() && 1634 MemRecord->getDeclName()) { 1635 // This is a nested type declaration. 1636 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1637 << (int)Record->isUnion(); 1638 Invalid = true; 1639 } 1640 } else { 1641 // We have something that isn't a non-static data 1642 // member. Complain about it. 1643 unsigned DK = diag::err_anonymous_record_bad_member; 1644 if (isa<TypeDecl>(*Mem)) 1645 DK = diag::err_anonymous_record_with_type; 1646 else if (isa<FunctionDecl>(*Mem)) 1647 DK = diag::err_anonymous_record_with_function; 1648 else if (isa<VarDecl>(*Mem)) 1649 DK = diag::err_anonymous_record_with_static; 1650 Diag((*Mem)->getLocation(), DK) 1651 << (int)Record->isUnion(); 1652 Invalid = true; 1653 } 1654 } 1655 } 1656 1657 if (!Record->isUnion() && !Owner->isRecord()) { 1658 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1659 << (int)getLangOptions().CPlusPlus; 1660 Invalid = true; 1661 } 1662 1663 // Mock up a declarator. 1664 Declarator Dc(DS, Declarator::TypeNameContext); 1665 TypeSourceInfo *TInfo = 0; 1666 GetTypeForDeclarator(Dc, S, &TInfo); 1667 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1668 1669 // Create a declaration for this anonymous struct/union. 1670 NamedDecl *Anon = 0; 1671 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1672 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1673 /*IdentifierInfo=*/0, 1674 Context.getTypeDeclType(Record), 1675 TInfo, 1676 /*BitWidth=*/0, /*Mutable=*/false); 1677 Anon->setAccess(AS_public); 1678 if (getLangOptions().CPlusPlus) 1679 FieldCollector->Add(cast<FieldDecl>(Anon)); 1680 } else { 1681 VarDecl::StorageClass SC; 1682 switch (DS.getStorageClassSpec()) { 1683 default: assert(0 && "Unknown storage class!"); 1684 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1685 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1686 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1687 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1688 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1689 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1690 case DeclSpec::SCS_mutable: 1691 // mutable can only appear on non-static class members, so it's always 1692 // an error here 1693 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1694 Invalid = true; 1695 SC = VarDecl::None; 1696 break; 1697 } 1698 1699 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1700 /*IdentifierInfo=*/0, 1701 Context.getTypeDeclType(Record), 1702 TInfo, 1703 SC); 1704 } 1705 Anon->setImplicit(); 1706 1707 // Add the anonymous struct/union object to the current 1708 // context. We'll be referencing this object when we refer to one of 1709 // its members. 1710 Owner->addDecl(Anon); 1711 1712 // Inject the members of the anonymous struct/union into the owning 1713 // context and into the identifier resolver chain for name lookup 1714 // purposes. 1715 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1716 Invalid = true; 1717 1718 // Mark this as an anonymous struct/union type. Note that we do not 1719 // do this until after we have already checked and injected the 1720 // members of this anonymous struct/union type, because otherwise 1721 // the members could be injected twice: once by DeclContext when it 1722 // builds its lookup table, and once by 1723 // InjectAnonymousStructOrUnionMembers. 1724 Record->setAnonymousStructOrUnion(true); 1725 1726 if (Invalid) 1727 Anon->setInvalidDecl(); 1728 1729 return DeclPtrTy::make(Anon); 1730} 1731 1732 1733/// GetNameForDeclarator - Determine the full declaration name for the 1734/// given Declarator. 1735DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1736 return GetNameFromUnqualifiedId(D.getName()); 1737} 1738 1739/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1740DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1741 switch (Name.getKind()) { 1742 case UnqualifiedId::IK_Identifier: 1743 return DeclarationName(Name.Identifier); 1744 1745 case UnqualifiedId::IK_OperatorFunctionId: 1746 return Context.DeclarationNames.getCXXOperatorName( 1747 Name.OperatorFunctionId.Operator); 1748 1749 case UnqualifiedId::IK_LiteralOperatorId: 1750 return Context.DeclarationNames.getCXXLiteralOperatorName( 1751 Name.Identifier); 1752 1753 case UnqualifiedId::IK_ConversionFunctionId: { 1754 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1755 if (Ty.isNull()) 1756 return DeclarationName(); 1757 1758 return Context.DeclarationNames.getCXXConversionFunctionName( 1759 Context.getCanonicalType(Ty)); 1760 } 1761 1762 case UnqualifiedId::IK_ConstructorName: { 1763 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1764 if (Ty.isNull()) 1765 return DeclarationName(); 1766 1767 return Context.DeclarationNames.getCXXConstructorName( 1768 Context.getCanonicalType(Ty)); 1769 } 1770 1771 case UnqualifiedId::IK_ConstructorTemplateId: { 1772 // In well-formed code, we can only have a constructor 1773 // template-id that refers to the current context, so go there 1774 // to find the actual type being constructed. 1775 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1776 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1777 return DeclarationName(); 1778 1779 // Determine the type of the class being constructed. 1780 QualType CurClassType = Context.getTypeDeclType(CurClass); 1781 1782 // FIXME: Check two things: that the template-id names the same type as 1783 // CurClassType, and that the template-id does not occur when the name 1784 // was qualified. 1785 1786 return Context.DeclarationNames.getCXXConstructorName( 1787 Context.getCanonicalType(CurClassType)); 1788 } 1789 1790 case UnqualifiedId::IK_DestructorName: { 1791 QualType Ty = GetTypeFromParser(Name.DestructorName); 1792 if (Ty.isNull()) 1793 return DeclarationName(); 1794 1795 return Context.DeclarationNames.getCXXDestructorName( 1796 Context.getCanonicalType(Ty)); 1797 } 1798 1799 case UnqualifiedId::IK_TemplateId: { 1800 TemplateName TName 1801 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1802 return Context.getNameForTemplate(TName); 1803 } 1804 } 1805 1806 assert(false && "Unknown name kind"); 1807 return DeclarationName(); 1808} 1809 1810/// isNearlyMatchingFunction - Determine whether the C++ functions 1811/// Declaration and Definition are "nearly" matching. This heuristic 1812/// is used to improve diagnostics in the case where an out-of-line 1813/// function definition doesn't match any declaration within 1814/// the class or namespace. 1815static bool isNearlyMatchingFunction(ASTContext &Context, 1816 FunctionDecl *Declaration, 1817 FunctionDecl *Definition) { 1818 if (Declaration->param_size() != Definition->param_size()) 1819 return false; 1820 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1821 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1822 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1823 1824 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1825 DefParamTy.getNonReferenceType())) 1826 return false; 1827 } 1828 1829 return true; 1830} 1831 1832Sema::DeclPtrTy 1833Sema::HandleDeclarator(Scope *S, Declarator &D, 1834 MultiTemplateParamsArg TemplateParamLists, 1835 bool IsFunctionDefinition) { 1836 DeclarationName Name = GetNameForDeclarator(D); 1837 1838 // All of these full declarators require an identifier. If it doesn't have 1839 // one, the ParsedFreeStandingDeclSpec action should be used. 1840 if (!Name) { 1841 if (!D.isInvalidType()) // Reject this if we think it is valid. 1842 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1843 diag::err_declarator_need_ident) 1844 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1845 return DeclPtrTy(); 1846 } 1847 1848 // The scope passed in may not be a decl scope. Zip up the scope tree until 1849 // we find one that is. 1850 while ((S->getFlags() & Scope::DeclScope) == 0 || 1851 (S->getFlags() & Scope::TemplateParamScope) != 0) 1852 S = S->getParent(); 1853 1854 // If this is an out-of-line definition of a member of a class template 1855 // or class template partial specialization, we may need to rebuild the 1856 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1857 // for more information. 1858 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1859 // handle expressions properly. 1860 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1861 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1862 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1863 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1864 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1865 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1866 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1867 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1868 // FIXME: Preserve type source info. 1869 QualType T = GetTypeFromParser(DS.getTypeRep()); 1870 1871 DeclContext *SavedContext = CurContext; 1872 CurContext = DC; 1873 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1874 CurContext = SavedContext; 1875 1876 if (T.isNull()) 1877 return DeclPtrTy(); 1878 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1879 } 1880 } 1881 1882 DeclContext *DC; 1883 NamedDecl *New; 1884 1885 TypeSourceInfo *TInfo = 0; 1886 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1887 1888 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1889 ForRedeclaration); 1890 1891 // See if this is a redefinition of a variable in the same scope. 1892 if (D.getCXXScopeSpec().isInvalid()) { 1893 DC = CurContext; 1894 D.setInvalidType(); 1895 } else if (!D.getCXXScopeSpec().isSet()) { 1896 bool IsLinkageLookup = false; 1897 1898 // If the declaration we're planning to build will be a function 1899 // or object with linkage, then look for another declaration with 1900 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1901 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1902 /* Do nothing*/; 1903 else if (R->isFunctionType()) { 1904 if (CurContext->isFunctionOrMethod() || 1905 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1906 IsLinkageLookup = true; 1907 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1908 IsLinkageLookup = true; 1909 else if (CurContext->getLookupContext()->isTranslationUnit() && 1910 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1911 IsLinkageLookup = true; 1912 1913 if (IsLinkageLookup) 1914 Previous.clear(LookupRedeclarationWithLinkage); 1915 1916 DC = CurContext; 1917 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1918 } else { // Something like "int foo::x;" 1919 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1920 1921 if (!DC) { 1922 // If we could not compute the declaration context, it's because the 1923 // declaration context is dependent but does not refer to a class, 1924 // class template, or class template partial specialization. Complain 1925 // and return early, to avoid the coming semantic disaster. 1926 Diag(D.getIdentifierLoc(), 1927 diag::err_template_qualified_declarator_no_match) 1928 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1929 << D.getCXXScopeSpec().getRange(); 1930 return DeclPtrTy(); 1931 } 1932 1933 if (!DC->isDependentContext() && 1934 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1935 return DeclPtrTy(); 1936 1937 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 1938 Diag(D.getIdentifierLoc(), 1939 diag::err_member_def_undefined_record) 1940 << Name << DC << D.getCXXScopeSpec().getRange(); 1941 D.setInvalidType(); 1942 } 1943 1944 LookupQualifiedName(Previous, DC); 1945 1946 // Don't consider using declarations as previous declarations for 1947 // out-of-line members. 1948 RemoveUsingDecls(Previous); 1949 1950 // C++ 7.3.1.2p2: 1951 // Members (including explicit specializations of templates) of a named 1952 // namespace can also be defined outside that namespace by explicit 1953 // qualification of the name being defined, provided that the entity being 1954 // defined was already declared in the namespace and the definition appears 1955 // after the point of declaration in a namespace that encloses the 1956 // declarations namespace. 1957 // 1958 // Note that we only check the context at this point. We don't yet 1959 // have enough information to make sure that PrevDecl is actually 1960 // the declaration we want to match. For example, given: 1961 // 1962 // class X { 1963 // void f(); 1964 // void f(float); 1965 // }; 1966 // 1967 // void X::f(int) { } // ill-formed 1968 // 1969 // In this case, PrevDecl will point to the overload set 1970 // containing the two f's declared in X, but neither of them 1971 // matches. 1972 1973 // First check whether we named the global scope. 1974 if (isa<TranslationUnitDecl>(DC)) { 1975 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1976 << Name << D.getCXXScopeSpec().getRange(); 1977 } else { 1978 DeclContext *Cur = CurContext; 1979 while (isa<LinkageSpecDecl>(Cur)) 1980 Cur = Cur->getParent(); 1981 if (!Cur->Encloses(DC)) { 1982 // The qualifying scope doesn't enclose the original declaration. 1983 // Emit diagnostic based on current scope. 1984 SourceLocation L = D.getIdentifierLoc(); 1985 SourceRange R = D.getCXXScopeSpec().getRange(); 1986 if (isa<FunctionDecl>(Cur)) 1987 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1988 else 1989 Diag(L, diag::err_invalid_declarator_scope) 1990 << Name << cast<NamedDecl>(DC) << R; 1991 D.setInvalidType(); 1992 } 1993 } 1994 } 1995 1996 if (Previous.isSingleResult() && 1997 Previous.getFoundDecl()->isTemplateParameter()) { 1998 // Maybe we will complain about the shadowed template parameter. 1999 if (!D.isInvalidType()) 2000 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2001 Previous.getFoundDecl())) 2002 D.setInvalidType(); 2003 2004 // Just pretend that we didn't see the previous declaration. 2005 Previous.clear(); 2006 } 2007 2008 // In C++, the previous declaration we find might be a tag type 2009 // (class or enum). In this case, the new declaration will hide the 2010 // tag type. Note that this does does not apply if we're declaring a 2011 // typedef (C++ [dcl.typedef]p4). 2012 if (Previous.isSingleTagDecl() && 2013 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2014 Previous.clear(); 2015 2016 bool Redeclaration = false; 2017 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2018 if (TemplateParamLists.size()) { 2019 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2020 return DeclPtrTy(); 2021 } 2022 2023 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2024 } else if (R->isFunctionType()) { 2025 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2026 move(TemplateParamLists), 2027 IsFunctionDefinition, Redeclaration); 2028 } else { 2029 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2030 move(TemplateParamLists), 2031 Redeclaration); 2032 } 2033 2034 if (New == 0) 2035 return DeclPtrTy(); 2036 2037 // If this has an identifier and is not an invalid redeclaration or 2038 // function template specialization, add it to the scope stack. 2039 if (Name && !(Redeclaration && New->isInvalidDecl())) 2040 PushOnScopeChains(New, S); 2041 2042 return DeclPtrTy::make(New); 2043} 2044 2045/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2046/// types into constant array types in certain situations which would otherwise 2047/// be errors (for GCC compatibility). 2048static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2049 ASTContext &Context, 2050 bool &SizeIsNegative) { 2051 // This method tries to turn a variable array into a constant 2052 // array even when the size isn't an ICE. This is necessary 2053 // for compatibility with code that depends on gcc's buggy 2054 // constant expression folding, like struct {char x[(int)(char*)2];} 2055 SizeIsNegative = false; 2056 2057 QualifierCollector Qs; 2058 const Type *Ty = Qs.strip(T); 2059 2060 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2061 QualType Pointee = PTy->getPointeeType(); 2062 QualType FixedType = 2063 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2064 if (FixedType.isNull()) return FixedType; 2065 FixedType = Context.getPointerType(FixedType); 2066 return Qs.apply(FixedType); 2067 } 2068 2069 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2070 if (!VLATy) 2071 return QualType(); 2072 // FIXME: We should probably handle this case 2073 if (VLATy->getElementType()->isVariablyModifiedType()) 2074 return QualType(); 2075 2076 Expr::EvalResult EvalResult; 2077 if (!VLATy->getSizeExpr() || 2078 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2079 !EvalResult.Val.isInt()) 2080 return QualType(); 2081 2082 llvm::APSInt &Res = EvalResult.Val.getInt(); 2083 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2084 // TODO: preserve the size expression in declarator info 2085 return Context.getConstantArrayType(VLATy->getElementType(), 2086 Res, ArrayType::Normal, 0); 2087 } 2088 2089 SizeIsNegative = true; 2090 return QualType(); 2091} 2092 2093/// \brief Register the given locally-scoped external C declaration so 2094/// that it can be found later for redeclarations 2095void 2096Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2097 const LookupResult &Previous, 2098 Scope *S) { 2099 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2100 "Decl is not a locally-scoped decl!"); 2101 // Note that we have a locally-scoped external with this name. 2102 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2103 2104 if (!Previous.isSingleResult()) 2105 return; 2106 2107 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2108 2109 // If there was a previous declaration of this variable, it may be 2110 // in our identifier chain. Update the identifier chain with the new 2111 // declaration. 2112 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2113 // The previous declaration was found on the identifer resolver 2114 // chain, so remove it from its scope. 2115 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2116 S = S->getParent(); 2117 2118 if (S) 2119 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2120 } 2121} 2122 2123/// \brief Diagnose function specifiers on a declaration of an identifier that 2124/// does not identify a function. 2125void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2126 // FIXME: We should probably indicate the identifier in question to avoid 2127 // confusion for constructs like "inline int a(), b;" 2128 if (D.getDeclSpec().isInlineSpecified()) 2129 Diag(D.getDeclSpec().getInlineSpecLoc(), 2130 diag::err_inline_non_function); 2131 2132 if (D.getDeclSpec().isVirtualSpecified()) 2133 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2134 diag::err_virtual_non_function); 2135 2136 if (D.getDeclSpec().isExplicitSpecified()) 2137 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2138 diag::err_explicit_non_function); 2139} 2140 2141NamedDecl* 2142Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2143 QualType R, TypeSourceInfo *TInfo, 2144 LookupResult &Previous, bool &Redeclaration) { 2145 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2146 if (D.getCXXScopeSpec().isSet()) { 2147 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2148 << D.getCXXScopeSpec().getRange(); 2149 D.setInvalidType(); 2150 // Pretend we didn't see the scope specifier. 2151 DC = CurContext; 2152 Previous.clear(); 2153 } 2154 2155 if (getLangOptions().CPlusPlus) { 2156 // Check that there are no default arguments (C++ only). 2157 CheckExtraCXXDefaultArguments(D); 2158 } 2159 2160 DiagnoseFunctionSpecifiers(D); 2161 2162 if (D.getDeclSpec().isThreadSpecified()) 2163 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2164 2165 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2166 if (!NewTD) return 0; 2167 2168 // Handle attributes prior to checking for duplicates in MergeVarDecl 2169 ProcessDeclAttributes(S, NewTD, D); 2170 2171 // Merge the decl with the existing one if appropriate. If the decl is 2172 // in an outer scope, it isn't the same thing. 2173 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2174 if (!Previous.empty()) { 2175 Redeclaration = true; 2176 MergeTypeDefDecl(NewTD, Previous); 2177 } 2178 2179 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2180 // then it shall have block scope. 2181 QualType T = NewTD->getUnderlyingType(); 2182 if (T->isVariablyModifiedType()) { 2183 FunctionNeedsScopeChecking() = true; 2184 2185 if (S->getFnParent() == 0) { 2186 bool SizeIsNegative; 2187 QualType FixedTy = 2188 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2189 if (!FixedTy.isNull()) { 2190 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2191 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2192 } else { 2193 if (SizeIsNegative) 2194 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2195 else if (T->isVariableArrayType()) 2196 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2197 else 2198 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2199 NewTD->setInvalidDecl(); 2200 } 2201 } 2202 } 2203 2204 // If this is the C FILE type, notify the AST context. 2205 if (IdentifierInfo *II = NewTD->getIdentifier()) 2206 if (!NewTD->isInvalidDecl() && 2207 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2208 if (II->isStr("FILE")) 2209 Context.setFILEDecl(NewTD); 2210 else if (II->isStr("jmp_buf")) 2211 Context.setjmp_bufDecl(NewTD); 2212 else if (II->isStr("sigjmp_buf")) 2213 Context.setsigjmp_bufDecl(NewTD); 2214 } 2215 2216 return NewTD; 2217} 2218 2219/// \brief Determines whether the given declaration is an out-of-scope 2220/// previous declaration. 2221/// 2222/// This routine should be invoked when name lookup has found a 2223/// previous declaration (PrevDecl) that is not in the scope where a 2224/// new declaration by the same name is being introduced. If the new 2225/// declaration occurs in a local scope, previous declarations with 2226/// linkage may still be considered previous declarations (C99 2227/// 6.2.2p4-5, C++ [basic.link]p6). 2228/// 2229/// \param PrevDecl the previous declaration found by name 2230/// lookup 2231/// 2232/// \param DC the context in which the new declaration is being 2233/// declared. 2234/// 2235/// \returns true if PrevDecl is an out-of-scope previous declaration 2236/// for a new delcaration with the same name. 2237static bool 2238isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2239 ASTContext &Context) { 2240 if (!PrevDecl) 2241 return 0; 2242 2243 if (!PrevDecl->hasLinkage()) 2244 return false; 2245 2246 if (Context.getLangOptions().CPlusPlus) { 2247 // C++ [basic.link]p6: 2248 // If there is a visible declaration of an entity with linkage 2249 // having the same name and type, ignoring entities declared 2250 // outside the innermost enclosing namespace scope, the block 2251 // scope declaration declares that same entity and receives the 2252 // linkage of the previous declaration. 2253 DeclContext *OuterContext = DC->getLookupContext(); 2254 if (!OuterContext->isFunctionOrMethod()) 2255 // This rule only applies to block-scope declarations. 2256 return false; 2257 else { 2258 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2259 if (PrevOuterContext->isRecord()) 2260 // We found a member function: ignore it. 2261 return false; 2262 else { 2263 // Find the innermost enclosing namespace for the new and 2264 // previous declarations. 2265 while (!OuterContext->isFileContext()) 2266 OuterContext = OuterContext->getParent(); 2267 while (!PrevOuterContext->isFileContext()) 2268 PrevOuterContext = PrevOuterContext->getParent(); 2269 2270 // The previous declaration is in a different namespace, so it 2271 // isn't the same function. 2272 if (OuterContext->getPrimaryContext() != 2273 PrevOuterContext->getPrimaryContext()) 2274 return false; 2275 } 2276 } 2277 } 2278 2279 return true; 2280} 2281 2282static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2283 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2284 if (!SS.isSet()) return; 2285 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2286 SS.getRange()); 2287} 2288 2289NamedDecl* 2290Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2291 QualType R, TypeSourceInfo *TInfo, 2292 LookupResult &Previous, 2293 MultiTemplateParamsArg TemplateParamLists, 2294 bool &Redeclaration) { 2295 DeclarationName Name = GetNameForDeclarator(D); 2296 2297 // Check that there are no default arguments (C++ only). 2298 if (getLangOptions().CPlusPlus) 2299 CheckExtraCXXDefaultArguments(D); 2300 2301 VarDecl *NewVD; 2302 VarDecl::StorageClass SC; 2303 switch (D.getDeclSpec().getStorageClassSpec()) { 2304 default: assert(0 && "Unknown storage class!"); 2305 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2306 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2307 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2308 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2309 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2310 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2311 case DeclSpec::SCS_mutable: 2312 // mutable can only appear on non-static class members, so it's always 2313 // an error here 2314 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2315 D.setInvalidType(); 2316 SC = VarDecl::None; 2317 break; 2318 } 2319 2320 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2321 if (!II) { 2322 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2323 << Name.getAsString(); 2324 return 0; 2325 } 2326 2327 DiagnoseFunctionSpecifiers(D); 2328 2329 if (!DC->isRecord() && S->getFnParent() == 0) { 2330 // C99 6.9p2: The storage-class specifiers auto and register shall not 2331 // appear in the declaration specifiers in an external declaration. 2332 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2333 2334 // If this is a register variable with an asm label specified, then this 2335 // is a GNU extension. 2336 if (SC == VarDecl::Register && D.getAsmLabel()) 2337 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2338 else 2339 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2340 D.setInvalidType(); 2341 } 2342 } 2343 if (DC->isRecord() && !CurContext->isRecord()) { 2344 // This is an out-of-line definition of a static data member. 2345 if (SC == VarDecl::Static) { 2346 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2347 diag::err_static_out_of_line) 2348 << CodeModificationHint::CreateRemoval( 2349 D.getDeclSpec().getStorageClassSpecLoc()); 2350 } else if (SC == VarDecl::None) 2351 SC = VarDecl::Static; 2352 } 2353 if (SC == VarDecl::Static) { 2354 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2355 if (RD->isLocalClass()) 2356 Diag(D.getIdentifierLoc(), 2357 diag::err_static_data_member_not_allowed_in_local_class) 2358 << Name << RD->getDeclName(); 2359 } 2360 } 2361 2362 // Match up the template parameter lists with the scope specifier, then 2363 // determine whether we have a template or a template specialization. 2364 bool isExplicitSpecialization = false; 2365 if (TemplateParameterList *TemplateParams 2366 = MatchTemplateParametersToScopeSpecifier( 2367 D.getDeclSpec().getSourceRange().getBegin(), 2368 D.getCXXScopeSpec(), 2369 (TemplateParameterList**)TemplateParamLists.get(), 2370 TemplateParamLists.size(), 2371 isExplicitSpecialization)) { 2372 if (TemplateParams->size() > 0) { 2373 // There is no such thing as a variable template. 2374 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2375 << II 2376 << SourceRange(TemplateParams->getTemplateLoc(), 2377 TemplateParams->getRAngleLoc()); 2378 return 0; 2379 } else { 2380 // There is an extraneous 'template<>' for this variable. Complain 2381 // about it, but allow the declaration of the variable. 2382 Diag(TemplateParams->getTemplateLoc(), 2383 diag::err_template_variable_noparams) 2384 << II 2385 << SourceRange(TemplateParams->getTemplateLoc(), 2386 TemplateParams->getRAngleLoc()); 2387 2388 isExplicitSpecialization = true; 2389 } 2390 } 2391 2392 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2393 II, R, TInfo, SC); 2394 2395 if (D.isInvalidType()) 2396 NewVD->setInvalidDecl(); 2397 2398 SetNestedNameSpecifier(NewVD, D); 2399 2400 if (D.getDeclSpec().isThreadSpecified()) { 2401 if (NewVD->hasLocalStorage()) 2402 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2403 else if (!Context.Target.isTLSSupported()) 2404 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2405 else 2406 NewVD->setThreadSpecified(true); 2407 } 2408 2409 // Set the lexical context. If the declarator has a C++ scope specifier, the 2410 // lexical context will be different from the semantic context. 2411 NewVD->setLexicalDeclContext(CurContext); 2412 2413 // Handle attributes prior to checking for duplicates in MergeVarDecl 2414 ProcessDeclAttributes(S, NewVD, D); 2415 2416 // Handle GNU asm-label extension (encoded as an attribute). 2417 if (Expr *E = (Expr*) D.getAsmLabel()) { 2418 // The parser guarantees this is a string. 2419 StringLiteral *SE = cast<StringLiteral>(E); 2420 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2421 } 2422 2423 // Diagnose shadowed variables before filtering for scope. 2424 if (!D.getCXXScopeSpec().isSet()) 2425 CheckShadow(S, NewVD, Previous); 2426 2427 // Don't consider existing declarations that are in a different 2428 // scope and are out-of-semantic-context declarations (if the new 2429 // declaration has linkage). 2430 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2431 2432 // Merge the decl with the existing one if appropriate. 2433 if (!Previous.empty()) { 2434 if (Previous.isSingleResult() && 2435 isa<FieldDecl>(Previous.getFoundDecl()) && 2436 D.getCXXScopeSpec().isSet()) { 2437 // The user tried to define a non-static data member 2438 // out-of-line (C++ [dcl.meaning]p1). 2439 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2440 << D.getCXXScopeSpec().getRange(); 2441 Previous.clear(); 2442 NewVD->setInvalidDecl(); 2443 } 2444 } else if (D.getCXXScopeSpec().isSet()) { 2445 // No previous declaration in the qualifying scope. 2446 Diag(D.getIdentifierLoc(), diag::err_no_member) 2447 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2448 << D.getCXXScopeSpec().getRange(); 2449 NewVD->setInvalidDecl(); 2450 } 2451 2452 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2453 2454 // This is an explicit specialization of a static data member. Check it. 2455 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2456 CheckMemberSpecialization(NewVD, Previous)) 2457 NewVD->setInvalidDecl(); 2458 2459 // attributes declared post-definition are currently ignored 2460 if (Previous.isSingleResult()) { 2461 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2462 if (Def && (Def = Def->getDefinition()) && 2463 Def != NewVD && D.hasAttributes()) { 2464 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2465 Diag(Def->getLocation(), diag::note_previous_definition); 2466 } 2467 } 2468 2469 // If this is a locally-scoped extern C variable, update the map of 2470 // such variables. 2471 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2472 !NewVD->isInvalidDecl()) 2473 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2474 2475 return NewVD; 2476} 2477 2478/// \brief Diagnose variable or built-in function shadowing. Implements 2479/// -Wshadow. 2480/// 2481/// This method is called whenever a VarDecl is added to a "useful" 2482/// scope. 2483/// 2484/// \param S the scope in which the shadowing name is being declared 2485/// \param R the lookup of the name 2486/// 2487void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2488 // Return if warning is ignored. 2489 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2490 return; 2491 2492 // Don't diagnose declarations at file scope. The scope might not 2493 // have a DeclContext if (e.g.) we're parsing a function prototype. 2494 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2495 if (NewDC && NewDC->isFileContext()) 2496 return; 2497 2498 // Only diagnose if we're shadowing an unambiguous field or variable. 2499 if (R.getResultKind() != LookupResult::Found) 2500 return; 2501 2502 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2503 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2504 return; 2505 2506 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2507 2508 // Only warn about certain kinds of shadowing for class members. 2509 if (NewDC && NewDC->isRecord()) { 2510 // In particular, don't warn about shadowing non-class members. 2511 if (!OldDC->isRecord()) 2512 return; 2513 2514 // TODO: should we warn about static data members shadowing 2515 // static data members from base classes? 2516 2517 // TODO: don't diagnose for inaccessible shadowed members. 2518 // This is hard to do perfectly because we might friend the 2519 // shadowing context, but that's just a false negative. 2520 } 2521 2522 // Determine what kind of declaration we're shadowing. 2523 unsigned Kind; 2524 if (isa<RecordDecl>(OldDC)) { 2525 if (isa<FieldDecl>(ShadowedDecl)) 2526 Kind = 3; // field 2527 else 2528 Kind = 2; // static data member 2529 } else if (OldDC->isFileContext()) 2530 Kind = 1; // global 2531 else 2532 Kind = 0; // local 2533 2534 DeclarationName Name = R.getLookupName(); 2535 2536 // Emit warning and note. 2537 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2538 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2539} 2540 2541/// \brief Check -Wshadow without the advantage of a previous lookup. 2542void Sema::CheckShadow(Scope *S, VarDecl *D) { 2543 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2544 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2545 LookupName(R, S); 2546 CheckShadow(S, D, R); 2547} 2548 2549/// \brief Perform semantic checking on a newly-created variable 2550/// declaration. 2551/// 2552/// This routine performs all of the type-checking required for a 2553/// variable declaration once it has been built. It is used both to 2554/// check variables after they have been parsed and their declarators 2555/// have been translated into a declaration, and to check variables 2556/// that have been instantiated from a template. 2557/// 2558/// Sets NewVD->isInvalidDecl() if an error was encountered. 2559void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2560 LookupResult &Previous, 2561 bool &Redeclaration) { 2562 // If the decl is already known invalid, don't check it. 2563 if (NewVD->isInvalidDecl()) 2564 return; 2565 2566 QualType T = NewVD->getType(); 2567 2568 if (T->isObjCInterfaceType()) { 2569 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2570 return NewVD->setInvalidDecl(); 2571 } 2572 2573 // Emit an error if an address space was applied to decl with local storage. 2574 // This includes arrays of objects with address space qualifiers, but not 2575 // automatic variables that point to other address spaces. 2576 // ISO/IEC TR 18037 S5.1.2 2577 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2578 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2579 return NewVD->setInvalidDecl(); 2580 } 2581 2582 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2583 && !NewVD->hasAttr<BlocksAttr>()) 2584 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2585 2586 bool isVM = T->isVariablyModifiedType(); 2587 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2588 NewVD->hasAttr<BlocksAttr>() || 2589 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2590 // However, this turns on the scope checker for everything with a variable 2591 // which may impact compile time. See if we can find a better solution 2592 // to this, perhaps only checking functions that contain gotos in C++? 2593 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2594 FunctionNeedsScopeChecking() = true; 2595 2596 if ((isVM && NewVD->hasLinkage()) || 2597 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2598 bool SizeIsNegative; 2599 QualType FixedTy = 2600 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2601 2602 if (FixedTy.isNull() && T->isVariableArrayType()) { 2603 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2604 // FIXME: This won't give the correct result for 2605 // int a[10][n]; 2606 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2607 2608 if (NewVD->isFileVarDecl()) 2609 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2610 << SizeRange; 2611 else if (NewVD->getStorageClass() == VarDecl::Static) 2612 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2613 << SizeRange; 2614 else 2615 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2616 << SizeRange; 2617 return NewVD->setInvalidDecl(); 2618 } 2619 2620 if (FixedTy.isNull()) { 2621 if (NewVD->isFileVarDecl()) 2622 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2623 else 2624 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2625 return NewVD->setInvalidDecl(); 2626 } 2627 2628 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2629 NewVD->setType(FixedTy); 2630 } 2631 2632 if (Previous.empty() && NewVD->isExternC()) { 2633 // Since we did not find anything by this name and we're declaring 2634 // an extern "C" variable, look for a non-visible extern "C" 2635 // declaration with the same name. 2636 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2637 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2638 if (Pos != LocallyScopedExternalDecls.end()) 2639 Previous.addDecl(Pos->second); 2640 } 2641 2642 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2643 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2644 << T; 2645 return NewVD->setInvalidDecl(); 2646 } 2647 2648 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2649 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2650 return NewVD->setInvalidDecl(); 2651 } 2652 2653 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2654 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2655 return NewVD->setInvalidDecl(); 2656 } 2657 2658 if (!Previous.empty()) { 2659 Redeclaration = true; 2660 MergeVarDecl(NewVD, Previous); 2661 } 2662} 2663 2664/// \brief Data used with FindOverriddenMethod 2665struct FindOverriddenMethodData { 2666 Sema *S; 2667 CXXMethodDecl *Method; 2668}; 2669 2670/// \brief Member lookup function that determines whether a given C++ 2671/// method overrides a method in a base class, to be used with 2672/// CXXRecordDecl::lookupInBases(). 2673static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2674 CXXBasePath &Path, 2675 void *UserData) { 2676 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2677 2678 FindOverriddenMethodData *Data 2679 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2680 2681 DeclarationName Name = Data->Method->getDeclName(); 2682 2683 // FIXME: Do we care about other names here too? 2684 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2685 // We really want to find the base class constructor here. 2686 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2687 CanQualType CT = Data->S->Context.getCanonicalType(T); 2688 2689 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2690 } 2691 2692 for (Path.Decls = BaseRecord->lookup(Name); 2693 Path.Decls.first != Path.Decls.second; 2694 ++Path.Decls.first) { 2695 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2696 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2697 return true; 2698 } 2699 } 2700 2701 return false; 2702} 2703 2704/// AddOverriddenMethods - See if a method overrides any in the base classes, 2705/// and if so, check that it's a valid override and remember it. 2706void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2707 // Look for virtual methods in base classes that this method might override. 2708 CXXBasePaths Paths; 2709 FindOverriddenMethodData Data; 2710 Data.Method = MD; 2711 Data.S = this; 2712 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2713 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2714 E = Paths.found_decls_end(); I != E; ++I) { 2715 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2716 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2717 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2718 !CheckOverridingFunctionAttributes(MD, OldMD)) 2719 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2720 } 2721 } 2722 } 2723} 2724 2725NamedDecl* 2726Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2727 QualType R, TypeSourceInfo *TInfo, 2728 LookupResult &Previous, 2729 MultiTemplateParamsArg TemplateParamLists, 2730 bool IsFunctionDefinition, bool &Redeclaration) { 2731 assert(R.getTypePtr()->isFunctionType()); 2732 2733 DeclarationName Name = GetNameForDeclarator(D); 2734 FunctionDecl::StorageClass SC = FunctionDecl::None; 2735 switch (D.getDeclSpec().getStorageClassSpec()) { 2736 default: assert(0 && "Unknown storage class!"); 2737 case DeclSpec::SCS_auto: 2738 case DeclSpec::SCS_register: 2739 case DeclSpec::SCS_mutable: 2740 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2741 diag::err_typecheck_sclass_func); 2742 D.setInvalidType(); 2743 break; 2744 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2745 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2746 case DeclSpec::SCS_static: { 2747 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2748 // C99 6.7.1p5: 2749 // The declaration of an identifier for a function that has 2750 // block scope shall have no explicit storage-class specifier 2751 // other than extern 2752 // See also (C++ [dcl.stc]p4). 2753 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2754 diag::err_static_block_func); 2755 SC = FunctionDecl::None; 2756 } else 2757 SC = FunctionDecl::Static; 2758 break; 2759 } 2760 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2761 } 2762 2763 if (D.getDeclSpec().isThreadSpecified()) 2764 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2765 2766 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2767 bool isInline = D.getDeclSpec().isInlineSpecified(); 2768 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2769 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2770 2771 // Check that the return type is not an abstract class type. 2772 // For record types, this is done by the AbstractClassUsageDiagnoser once 2773 // the class has been completely parsed. 2774 if (!DC->isRecord() && 2775 RequireNonAbstractType(D.getIdentifierLoc(), 2776 R->getAs<FunctionType>()->getResultType(), 2777 diag::err_abstract_type_in_decl, 2778 AbstractReturnType)) 2779 D.setInvalidType(); 2780 2781 // Do not allow returning a objc interface by-value. 2782 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2783 Diag(D.getIdentifierLoc(), 2784 diag::err_object_cannot_be_passed_returned_by_value) << 0 2785 << R->getAs<FunctionType>()->getResultType(); 2786 D.setInvalidType(); 2787 } 2788 2789 bool isVirtualOkay = false; 2790 FunctionDecl *NewFD; 2791 2792 if (isFriend) { 2793 // C++ [class.friend]p5 2794 // A function can be defined in a friend declaration of a 2795 // class . . . . Such a function is implicitly inline. 2796 isInline |= IsFunctionDefinition; 2797 } 2798 2799 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2800 // This is a C++ constructor declaration. 2801 assert(DC->isRecord() && 2802 "Constructors can only be declared in a member context"); 2803 2804 R = CheckConstructorDeclarator(D, R, SC); 2805 2806 // Create the new declaration 2807 NewFD = CXXConstructorDecl::Create(Context, 2808 cast<CXXRecordDecl>(DC), 2809 D.getIdentifierLoc(), Name, R, TInfo, 2810 isExplicit, isInline, 2811 /*isImplicitlyDeclared=*/false); 2812 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2813 // This is a C++ destructor declaration. 2814 if (DC->isRecord()) { 2815 R = CheckDestructorDeclarator(D, SC); 2816 2817 NewFD = CXXDestructorDecl::Create(Context, 2818 cast<CXXRecordDecl>(DC), 2819 D.getIdentifierLoc(), Name, R, 2820 isInline, 2821 /*isImplicitlyDeclared=*/false); 2822 NewFD->setTypeSourceInfo(TInfo); 2823 2824 isVirtualOkay = true; 2825 } else { 2826 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2827 2828 // Create a FunctionDecl to satisfy the function definition parsing 2829 // code path. 2830 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2831 Name, R, TInfo, SC, isInline, 2832 /*hasPrototype=*/true); 2833 D.setInvalidType(); 2834 } 2835 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2836 if (!DC->isRecord()) { 2837 Diag(D.getIdentifierLoc(), 2838 diag::err_conv_function_not_member); 2839 return 0; 2840 } 2841 2842 CheckConversionDeclarator(D, R, SC); 2843 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2844 D.getIdentifierLoc(), Name, R, TInfo, 2845 isInline, isExplicit); 2846 2847 isVirtualOkay = true; 2848 } else if (DC->isRecord()) { 2849 // If the of the function is the same as the name of the record, then this 2850 // must be an invalid constructor that has a return type. 2851 // (The parser checks for a return type and makes the declarator a 2852 // constructor if it has no return type). 2853 // must have an invalid constructor that has a return type 2854 if (Name.getAsIdentifierInfo() && 2855 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2856 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2857 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2858 << SourceRange(D.getIdentifierLoc()); 2859 return 0; 2860 } 2861 2862 bool isStatic = SC == FunctionDecl::Static; 2863 2864 // [class.free]p1: 2865 // Any allocation function for a class T is a static member 2866 // (even if not explicitly declared static). 2867 if (Name.getCXXOverloadedOperator() == OO_New || 2868 Name.getCXXOverloadedOperator() == OO_Array_New) 2869 isStatic = true; 2870 2871 // [class.free]p6 Any deallocation function for a class X is a static member 2872 // (even if not explicitly declared static). 2873 if (Name.getCXXOverloadedOperator() == OO_Delete || 2874 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2875 isStatic = true; 2876 2877 // This is a C++ method declaration. 2878 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2879 D.getIdentifierLoc(), Name, R, TInfo, 2880 isStatic, isInline); 2881 2882 isVirtualOkay = !isStatic; 2883 } else { 2884 // Determine whether the function was written with a 2885 // prototype. This true when: 2886 // - we're in C++ (where every function has a prototype), 2887 // - there is a prototype in the declarator, or 2888 // - the type R of the function is some kind of typedef or other reference 2889 // to a type name (which eventually refers to a function type). 2890 bool HasPrototype = 2891 getLangOptions().CPlusPlus || 2892 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2893 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2894 2895 NewFD = FunctionDecl::Create(Context, DC, 2896 D.getIdentifierLoc(), 2897 Name, R, TInfo, SC, isInline, HasPrototype); 2898 } 2899 2900 if (D.isInvalidType()) 2901 NewFD->setInvalidDecl(); 2902 2903 SetNestedNameSpecifier(NewFD, D); 2904 2905 // Set the lexical context. If the declarator has a C++ 2906 // scope specifier, or is the object of a friend declaration, the 2907 // lexical context will be different from the semantic context. 2908 NewFD->setLexicalDeclContext(CurContext); 2909 2910 // Match up the template parameter lists with the scope specifier, then 2911 // determine whether we have a template or a template specialization. 2912 FunctionTemplateDecl *FunctionTemplate = 0; 2913 bool isExplicitSpecialization = false; 2914 bool isFunctionTemplateSpecialization = false; 2915 if (TemplateParameterList *TemplateParams 2916 = MatchTemplateParametersToScopeSpecifier( 2917 D.getDeclSpec().getSourceRange().getBegin(), 2918 D.getCXXScopeSpec(), 2919 (TemplateParameterList**)TemplateParamLists.get(), 2920 TemplateParamLists.size(), 2921 isExplicitSpecialization)) { 2922 if (TemplateParams->size() > 0) { 2923 // This is a function template 2924 2925 // Check that we can declare a template here. 2926 if (CheckTemplateDeclScope(S, TemplateParams)) 2927 return 0; 2928 2929 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2930 NewFD->getLocation(), 2931 Name, TemplateParams, 2932 NewFD); 2933 FunctionTemplate->setLexicalDeclContext(CurContext); 2934 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2935 } else { 2936 // This is a function template specialization. 2937 isFunctionTemplateSpecialization = true; 2938 2939 // C++0x [temp.expl.spec]p20 forbids "template<> void foo(int);". 2940 if (isFriend && isFunctionTemplateSpecialization) { 2941 // We want to remove the "template<>", found here. 2942 SourceRange RemoveRange = TemplateParams->getSourceRange(); 2943 2944 // If we remove the template<> and the name is not a 2945 // template-id, we're actually silently creating a problem: 2946 // the friend declaration will refer to an untemplated decl, 2947 // and clearly the user wants a template specialization. So 2948 // we need to insert '<>' after the name. 2949 SourceLocation InsertLoc; 2950 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 2951 InsertLoc = D.getName().getSourceRange().getEnd(); 2952 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 2953 } 2954 2955 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 2956 << Name << RemoveRange 2957 << CodeModificationHint::CreateRemoval(RemoveRange) 2958 << CodeModificationHint::CreateInsertion(InsertLoc, "<>"); 2959 } 2960 } 2961 2962 // FIXME: Free this memory properly. 2963 TemplateParamLists.release(); 2964 } 2965 2966 // C++ [dcl.fct.spec]p5: 2967 // The virtual specifier shall only be used in declarations of 2968 // nonstatic class member functions that appear within a 2969 // member-specification of a class declaration; see 10.3. 2970 // 2971 if (isVirtual && !NewFD->isInvalidDecl()) { 2972 if (!isVirtualOkay) { 2973 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2974 diag::err_virtual_non_function); 2975 } else if (!CurContext->isRecord()) { 2976 // 'virtual' was specified outside of the class. 2977 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2978 << CodeModificationHint::CreateRemoval( 2979 D.getDeclSpec().getVirtualSpecLoc()); 2980 } else { 2981 // Okay: Add virtual to the method. 2982 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2983 CurClass->setMethodAsVirtual(NewFD); 2984 } 2985 } 2986 2987 // C++ [dcl.fct.spec]p6: 2988 // The explicit specifier shall be used only in the declaration of a 2989 // constructor or conversion function within its class definition; see 12.3.1 2990 // and 12.3.2. 2991 if (isExplicit && !NewFD->isInvalidDecl()) { 2992 if (!CurContext->isRecord()) { 2993 // 'explicit' was specified outside of the class. 2994 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2995 diag::err_explicit_out_of_class) 2996 << CodeModificationHint::CreateRemoval( 2997 D.getDeclSpec().getExplicitSpecLoc()); 2998 } else if (!isa<CXXConstructorDecl>(NewFD) && 2999 !isa<CXXConversionDecl>(NewFD)) { 3000 // 'explicit' was specified on a function that wasn't a constructor 3001 // or conversion function. 3002 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3003 diag::err_explicit_non_ctor_or_conv_function) 3004 << CodeModificationHint::CreateRemoval( 3005 D.getDeclSpec().getExplicitSpecLoc()); 3006 } 3007 } 3008 3009 // Filter out previous declarations that don't match the scope. 3010 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3011 3012 if (isFriend) { 3013 // DC is the namespace in which the function is being declared. 3014 assert((DC->isFileContext() || !Previous.empty()) && 3015 "previously-undeclared friend function being created " 3016 "in a non-namespace context"); 3017 3018 // For now, claim that the objects have no previous declaration. 3019 if (FunctionTemplate) { 3020 FunctionTemplate->setObjectOfFriendDecl(false); 3021 FunctionTemplate->setAccess(AS_public); 3022 } else { 3023 NewFD->setObjectOfFriendDecl(false); 3024 } 3025 3026 NewFD->setAccess(AS_public); 3027 } 3028 3029 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3030 !CurContext->isRecord()) { 3031 // C++ [class.static]p1: 3032 // A data or function member of a class may be declared static 3033 // in a class definition, in which case it is a static member of 3034 // the class. 3035 3036 // Complain about the 'static' specifier if it's on an out-of-line 3037 // member function definition. 3038 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3039 diag::err_static_out_of_line) 3040 << CodeModificationHint::CreateRemoval( 3041 D.getDeclSpec().getStorageClassSpecLoc()); 3042 } 3043 3044 // Handle GNU asm-label extension (encoded as an attribute). 3045 if (Expr *E = (Expr*) D.getAsmLabel()) { 3046 // The parser guarantees this is a string. 3047 StringLiteral *SE = cast<StringLiteral>(E); 3048 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3049 } 3050 3051 // Copy the parameter declarations from the declarator D to the function 3052 // declaration NewFD, if they are available. First scavenge them into Params. 3053 llvm::SmallVector<ParmVarDecl*, 16> Params; 3054 if (D.getNumTypeObjects() > 0) { 3055 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3056 3057 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3058 // function that takes no arguments, not a function that takes a 3059 // single void argument. 3060 // We let through "const void" here because Sema::GetTypeForDeclarator 3061 // already checks for that case. 3062 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3063 FTI.ArgInfo[0].Param && 3064 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3065 // Empty arg list, don't push any params. 3066 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3067 3068 // In C++, the empty parameter-type-list must be spelled "void"; a 3069 // typedef of void is not permitted. 3070 if (getLangOptions().CPlusPlus && 3071 Param->getType().getUnqualifiedType() != Context.VoidTy) 3072 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3073 // FIXME: Leaks decl? 3074 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3075 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3076 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3077 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3078 Param->setDeclContext(NewFD); 3079 Params.push_back(Param); 3080 } 3081 } 3082 3083 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3084 // When we're declaring a function with a typedef, typeof, etc as in the 3085 // following example, we'll need to synthesize (unnamed) 3086 // parameters for use in the declaration. 3087 // 3088 // @code 3089 // typedef void fn(int); 3090 // fn f; 3091 // @endcode 3092 3093 // Synthesize a parameter for each argument type. 3094 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3095 AE = FT->arg_type_end(); AI != AE; ++AI) { 3096 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 3097 SourceLocation(), 0, 3098 *AI, /*TInfo=*/0, 3099 VarDecl::None, 0); 3100 Param->setImplicit(); 3101 Params.push_back(Param); 3102 } 3103 } else { 3104 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3105 "Should not need args for typedef of non-prototype fn"); 3106 } 3107 // Finally, we know we have the right number of parameters, install them. 3108 NewFD->setParams(Params.data(), Params.size()); 3109 3110 // If the declarator is a template-id, translate the parser's template 3111 // argument list into our AST format. 3112 bool HasExplicitTemplateArgs = false; 3113 TemplateArgumentListInfo TemplateArgs; 3114 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3115 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3116 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3117 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3118 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3119 TemplateId->getTemplateArgs(), 3120 TemplateId->NumArgs); 3121 translateTemplateArguments(TemplateArgsPtr, 3122 TemplateArgs); 3123 TemplateArgsPtr.release(); 3124 3125 HasExplicitTemplateArgs = true; 3126 3127 if (FunctionTemplate) { 3128 // FIXME: Diagnose function template with explicit template 3129 // arguments. 3130 HasExplicitTemplateArgs = false; 3131 } else if (!isFunctionTemplateSpecialization && 3132 !D.getDeclSpec().isFriendSpecified()) { 3133 // We have encountered something that the user meant to be a 3134 // specialization (because it has explicitly-specified template 3135 // arguments) but that was not introduced with a "template<>" (or had 3136 // too few of them). 3137 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3138 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3139 << CodeModificationHint::CreateInsertion( 3140 D.getDeclSpec().getSourceRange().getBegin(), 3141 "template<> "); 3142 isFunctionTemplateSpecialization = true; 3143 } else { 3144 // "friend void foo<>(int);" is an implicit specialization decl. 3145 isFunctionTemplateSpecialization = true; 3146 } 3147 } 3148 3149 if (isFunctionTemplateSpecialization) { 3150 if (isFriend && NewFD->getType()->isDependentType()) { 3151 // FIXME: When we see a friend of a function template 3152 // specialization with a dependent type, we can't match it now; 3153 // for now, we just drop it, until we have a reasonable way to 3154 // represent the parsed-but-not-matched friend function template 3155 // specialization in the AST. 3156 return 0; 3157 } else if (CheckFunctionTemplateSpecialization(NewFD, 3158 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3159 Previous)) 3160 NewFD->setInvalidDecl(); 3161 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3162 CheckMemberSpecialization(NewFD, Previous)) 3163 NewFD->setInvalidDecl(); 3164 3165 // Perform semantic checking on the function declaration. 3166 bool OverloadableAttrRequired = false; // FIXME: HACK! 3167 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3168 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3169 3170 assert((NewFD->isInvalidDecl() || !Redeclaration || 3171 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3172 "previous declaration set still overloaded"); 3173 3174 if (isFriend && Redeclaration) { 3175 AccessSpecifier Access = NewFD->getPreviousDeclaration()->getAccess(); 3176 if (FunctionTemplate) { 3177 FunctionTemplate->setObjectOfFriendDecl(true); 3178 FunctionTemplate->setAccess(Access); 3179 } else { 3180 NewFD->setObjectOfFriendDecl(true); 3181 } 3182 NewFD->setAccess(Access); 3183 } 3184 3185 // If we have a function template, check the template parameter 3186 // list. This will check and merge default template arguments. 3187 if (FunctionTemplate) { 3188 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3189 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3190 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3191 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3192 : TPC_FunctionTemplate); 3193 } 3194 3195 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3196 // Fake up an access specifier if it's supposed to be a class member. 3197 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3198 NewFD->setAccess(AS_public); 3199 3200 // An out-of-line member function declaration must also be a 3201 // definition (C++ [dcl.meaning]p1). 3202 // Note that this is not the case for explicit specializations of 3203 // function templates or member functions of class templates, per 3204 // C++ [temp.expl.spec]p2. 3205 if (!IsFunctionDefinition && !isFriend && 3206 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3207 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3208 << D.getCXXScopeSpec().getRange(); 3209 NewFD->setInvalidDecl(); 3210 } else if (!Redeclaration && 3211 !(isFriend && CurContext->isDependentContext())) { 3212 // The user tried to provide an out-of-line definition for a 3213 // function that is a member of a class or namespace, but there 3214 // was no such member function declared (C++ [class.mfct]p2, 3215 // C++ [namespace.memdef]p2). For example: 3216 // 3217 // class X { 3218 // void f() const; 3219 // }; 3220 // 3221 // void X::f() { } // ill-formed 3222 // 3223 // Complain about this problem, and attempt to suggest close 3224 // matches (e.g., those that differ only in cv-qualifiers and 3225 // whether the parameter types are references). 3226 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3227 << Name << DC << D.getCXXScopeSpec().getRange(); 3228 NewFD->setInvalidDecl(); 3229 3230 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3231 ForRedeclaration); 3232 LookupQualifiedName(Prev, DC); 3233 assert(!Prev.isAmbiguous() && 3234 "Cannot have an ambiguity in previous-declaration lookup"); 3235 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3236 Func != FuncEnd; ++Func) { 3237 if (isa<FunctionDecl>(*Func) && 3238 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3239 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3240 } 3241 } 3242 } 3243 3244 // Handle attributes. We need to have merged decls when handling attributes 3245 // (for example to check for conflicts, etc). 3246 // FIXME: This needs to happen before we merge declarations. Then, 3247 // let attribute merging cope with attribute conflicts. 3248 ProcessDeclAttributes(S, NewFD, D); 3249 3250 // attributes declared post-definition are currently ignored 3251 if (Redeclaration && Previous.isSingleResult()) { 3252 const FunctionDecl *Def; 3253 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3254 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3255 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3256 Diag(Def->getLocation(), diag::note_previous_definition); 3257 } 3258 } 3259 3260 AddKnownFunctionAttributes(NewFD); 3261 3262 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3263 // If a function name is overloadable in C, then every function 3264 // with that name must be marked "overloadable". 3265 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3266 << Redeclaration << NewFD; 3267 if (!Previous.empty()) 3268 Diag(Previous.getRepresentativeDecl()->getLocation(), 3269 diag::note_attribute_overloadable_prev_overload); 3270 NewFD->addAttr(::new (Context) OverloadableAttr()); 3271 } 3272 3273 // If this is a locally-scoped extern C function, update the 3274 // map of such names. 3275 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3276 && !NewFD->isInvalidDecl()) 3277 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3278 3279 // Set this FunctionDecl's range up to the right paren. 3280 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3281 3282 if (FunctionTemplate && NewFD->isInvalidDecl()) 3283 FunctionTemplate->setInvalidDecl(); 3284 3285 if (FunctionTemplate) 3286 return FunctionTemplate; 3287 3288 3289 // Keep track of static, non-inlined function definitions that 3290 // have not been used. We will warn later. 3291 // FIXME: Also include static functions declared but not defined. 3292 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3293 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3294 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>()) 3295 UnusedStaticFuncs.push_back(NewFD); 3296 3297 return NewFD; 3298} 3299 3300/// \brief Perform semantic checking of a new function declaration. 3301/// 3302/// Performs semantic analysis of the new function declaration 3303/// NewFD. This routine performs all semantic checking that does not 3304/// require the actual declarator involved in the declaration, and is 3305/// used both for the declaration of functions as they are parsed 3306/// (called via ActOnDeclarator) and for the declaration of functions 3307/// that have been instantiated via C++ template instantiation (called 3308/// via InstantiateDecl). 3309/// 3310/// \param IsExplicitSpecialiation whether this new function declaration is 3311/// an explicit specialization of the previous declaration. 3312/// 3313/// This sets NewFD->isInvalidDecl() to true if there was an error. 3314void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3315 LookupResult &Previous, 3316 bool IsExplicitSpecialization, 3317 bool &Redeclaration, 3318 bool &OverloadableAttrRequired) { 3319 // If NewFD is already known erroneous, don't do any of this checking. 3320 if (NewFD->isInvalidDecl()) 3321 return; 3322 3323 if (NewFD->getResultType()->isVariablyModifiedType()) { 3324 // Functions returning a variably modified type violate C99 6.7.5.2p2 3325 // because all functions have linkage. 3326 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3327 return NewFD->setInvalidDecl(); 3328 } 3329 3330 if (NewFD->isMain()) 3331 CheckMain(NewFD); 3332 3333 // Check for a previous declaration of this name. 3334 if (Previous.empty() && NewFD->isExternC()) { 3335 // Since we did not find anything by this name and we're declaring 3336 // an extern "C" function, look for a non-visible extern "C" 3337 // declaration with the same name. 3338 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3339 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3340 if (Pos != LocallyScopedExternalDecls.end()) 3341 Previous.addDecl(Pos->second); 3342 } 3343 3344 // Merge or overload the declaration with an existing declaration of 3345 // the same name, if appropriate. 3346 if (!Previous.empty()) { 3347 // Determine whether NewFD is an overload of PrevDecl or 3348 // a declaration that requires merging. If it's an overload, 3349 // there's no more work to do here; we'll just add the new 3350 // function to the scope. 3351 3352 NamedDecl *OldDecl = 0; 3353 if (!AllowOverloadingOfFunction(Previous, Context)) { 3354 Redeclaration = true; 3355 OldDecl = Previous.getFoundDecl(); 3356 } else { 3357 if (!getLangOptions().CPlusPlus) { 3358 OverloadableAttrRequired = true; 3359 3360 // Functions marked "overloadable" must have a prototype (that 3361 // we can't get through declaration merging). 3362 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3363 Diag(NewFD->getLocation(), 3364 diag::err_attribute_overloadable_no_prototype) 3365 << NewFD; 3366 Redeclaration = true; 3367 3368 // Turn this into a variadic function with no parameters. 3369 QualType R = Context.getFunctionType( 3370 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3371 0, 0, true, 0, false, false, 0, 0, 3372 FunctionType::ExtInfo()); 3373 NewFD->setType(R); 3374 return NewFD->setInvalidDecl(); 3375 } 3376 } 3377 3378 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3379 case Ovl_Match: 3380 Redeclaration = true; 3381 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3382 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3383 Redeclaration = false; 3384 } 3385 break; 3386 3387 case Ovl_NonFunction: 3388 Redeclaration = true; 3389 break; 3390 3391 case Ovl_Overload: 3392 Redeclaration = false; 3393 break; 3394 } 3395 } 3396 3397 if (Redeclaration) { 3398 // NewFD and OldDecl represent declarations that need to be 3399 // merged. 3400 if (MergeFunctionDecl(NewFD, OldDecl)) 3401 return NewFD->setInvalidDecl(); 3402 3403 Previous.clear(); 3404 Previous.addDecl(OldDecl); 3405 3406 if (FunctionTemplateDecl *OldTemplateDecl 3407 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3408 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3409 FunctionTemplateDecl *NewTemplateDecl 3410 = NewFD->getDescribedFunctionTemplate(); 3411 assert(NewTemplateDecl && "Template/non-template mismatch"); 3412 if (CXXMethodDecl *Method 3413 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3414 Method->setAccess(OldTemplateDecl->getAccess()); 3415 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3416 } 3417 3418 // If this is an explicit specialization of a member that is a function 3419 // template, mark it as a member specialization. 3420 if (IsExplicitSpecialization && 3421 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3422 NewTemplateDecl->setMemberSpecialization(); 3423 assert(OldTemplateDecl->isMemberSpecialization()); 3424 } 3425 } else { 3426 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3427 NewFD->setAccess(OldDecl->getAccess()); 3428 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3429 } 3430 } 3431 } 3432 3433 // Semantic checking for this function declaration (in isolation). 3434 if (getLangOptions().CPlusPlus) { 3435 // C++-specific checks. 3436 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3437 CheckConstructor(Constructor); 3438 } else if (CXXDestructorDecl *Destructor = 3439 dyn_cast<CXXDestructorDecl>(NewFD)) { 3440 CXXRecordDecl *Record = Destructor->getParent(); 3441 QualType ClassType = Context.getTypeDeclType(Record); 3442 3443 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3444 // type is dependent? Both gcc and edg can handle that. 3445 if (!ClassType->isDependentType()) { 3446 DeclarationName Name 3447 = Context.DeclarationNames.getCXXDestructorName( 3448 Context.getCanonicalType(ClassType)); 3449 if (NewFD->getDeclName() != Name) { 3450 Diag(NewFD->getLocation(), diag::err_destructor_name); 3451 return NewFD->setInvalidDecl(); 3452 } 3453 } 3454 3455 Record->setUserDeclaredDestructor(true); 3456 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3457 // user-defined destructor. 3458 Record->setPOD(false); 3459 3460 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3461 // declared destructor. 3462 // FIXME: C++0x: don't do this for "= default" destructors 3463 Record->setHasTrivialDestructor(false); 3464 } else if (CXXConversionDecl *Conversion 3465 = dyn_cast<CXXConversionDecl>(NewFD)) { 3466 ActOnConversionDeclarator(Conversion); 3467 } 3468 3469 // Find any virtual functions that this function overrides. 3470 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3471 if (!Method->isFunctionTemplateSpecialization() && 3472 !Method->getDescribedFunctionTemplate()) 3473 AddOverriddenMethods(Method->getParent(), Method); 3474 } 3475 3476 // Additional checks for the destructor; make sure we do this after we 3477 // figure out whether the destructor is virtual. 3478 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3479 if (!Destructor->getParent()->isDependentType()) 3480 CheckDestructor(Destructor); 3481 3482 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3483 if (NewFD->isOverloadedOperator() && 3484 CheckOverloadedOperatorDeclaration(NewFD)) 3485 return NewFD->setInvalidDecl(); 3486 3487 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3488 if (NewFD->getLiteralIdentifier() && 3489 CheckLiteralOperatorDeclaration(NewFD)) 3490 return NewFD->setInvalidDecl(); 3491 3492 // In C++, check default arguments now that we have merged decls. Unless 3493 // the lexical context is the class, because in this case this is done 3494 // during delayed parsing anyway. 3495 if (!CurContext->isRecord()) 3496 CheckCXXDefaultArguments(NewFD); 3497 } 3498} 3499 3500void Sema::CheckMain(FunctionDecl* FD) { 3501 // C++ [basic.start.main]p3: A program that declares main to be inline 3502 // or static is ill-formed. 3503 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3504 // shall not appear in a declaration of main. 3505 // static main is not an error under C99, but we should warn about it. 3506 bool isInline = FD->isInlineSpecified(); 3507 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3508 if (isInline || isStatic) { 3509 unsigned diagID = diag::warn_unusual_main_decl; 3510 if (isInline || getLangOptions().CPlusPlus) 3511 diagID = diag::err_unusual_main_decl; 3512 3513 int which = isStatic + (isInline << 1) - 1; 3514 Diag(FD->getLocation(), diagID) << which; 3515 } 3516 3517 QualType T = FD->getType(); 3518 assert(T->isFunctionType() && "function decl is not of function type"); 3519 const FunctionType* FT = T->getAs<FunctionType>(); 3520 3521 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3522 // TODO: add a replacement fixit to turn the return type into 'int'. 3523 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3524 FD->setInvalidDecl(true); 3525 } 3526 3527 // Treat protoless main() as nullary. 3528 if (isa<FunctionNoProtoType>(FT)) return; 3529 3530 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3531 unsigned nparams = FTP->getNumArgs(); 3532 assert(FD->getNumParams() == nparams); 3533 3534 bool HasExtraParameters = (nparams > 3); 3535 3536 // Darwin passes an undocumented fourth argument of type char**. If 3537 // other platforms start sprouting these, the logic below will start 3538 // getting shifty. 3539 if (nparams == 4 && 3540 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3541 HasExtraParameters = false; 3542 3543 if (HasExtraParameters) { 3544 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3545 FD->setInvalidDecl(true); 3546 nparams = 3; 3547 } 3548 3549 // FIXME: a lot of the following diagnostics would be improved 3550 // if we had some location information about types. 3551 3552 QualType CharPP = 3553 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3554 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3555 3556 for (unsigned i = 0; i < nparams; ++i) { 3557 QualType AT = FTP->getArgType(i); 3558 3559 bool mismatch = true; 3560 3561 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3562 mismatch = false; 3563 else if (Expected[i] == CharPP) { 3564 // As an extension, the following forms are okay: 3565 // char const ** 3566 // char const * const * 3567 // char * const * 3568 3569 QualifierCollector qs; 3570 const PointerType* PT; 3571 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3572 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3573 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3574 qs.removeConst(); 3575 mismatch = !qs.empty(); 3576 } 3577 } 3578 3579 if (mismatch) { 3580 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3581 // TODO: suggest replacing given type with expected type 3582 FD->setInvalidDecl(true); 3583 } 3584 } 3585 3586 if (nparams == 1 && !FD->isInvalidDecl()) { 3587 Diag(FD->getLocation(), diag::warn_main_one_arg); 3588 } 3589} 3590 3591bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3592 // FIXME: Need strict checking. In C89, we need to check for 3593 // any assignment, increment, decrement, function-calls, or 3594 // commas outside of a sizeof. In C99, it's the same list, 3595 // except that the aforementioned are allowed in unevaluated 3596 // expressions. Everything else falls under the 3597 // "may accept other forms of constant expressions" exception. 3598 // (We never end up here for C++, so the constant expression 3599 // rules there don't matter.) 3600 if (Init->isConstantInitializer(Context)) 3601 return false; 3602 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3603 << Init->getSourceRange(); 3604 return true; 3605} 3606 3607void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3608 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3609} 3610 3611/// AddInitializerToDecl - Adds the initializer Init to the 3612/// declaration dcl. If DirectInit is true, this is C++ direct 3613/// initialization rather than copy initialization. 3614void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3615 Decl *RealDecl = dcl.getAs<Decl>(); 3616 // If there is no declaration, there was an error parsing it. Just ignore 3617 // the initializer. 3618 if (RealDecl == 0) 3619 return; 3620 3621 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3622 // With declarators parsed the way they are, the parser cannot 3623 // distinguish between a normal initializer and a pure-specifier. 3624 // Thus this grotesque test. 3625 IntegerLiteral *IL; 3626 Expr *Init = static_cast<Expr *>(init.get()); 3627 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3628 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3629 CheckPureMethod(Method, Init->getSourceRange()); 3630 else { 3631 Diag(Method->getLocation(), diag::err_member_function_initialization) 3632 << Method->getDeclName() << Init->getSourceRange(); 3633 Method->setInvalidDecl(); 3634 } 3635 return; 3636 } 3637 3638 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3639 if (!VDecl) { 3640 if (getLangOptions().CPlusPlus && 3641 RealDecl->getLexicalDeclContext()->isRecord() && 3642 isa<NamedDecl>(RealDecl)) 3643 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3644 << cast<NamedDecl>(RealDecl)->getDeclName(); 3645 else 3646 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3647 RealDecl->setInvalidDecl(); 3648 return; 3649 } 3650 3651 // A definition must end up with a complete type, which means it must be 3652 // complete with the restriction that an array type might be completed by the 3653 // initializer; note that later code assumes this restriction. 3654 QualType BaseDeclType = VDecl->getType(); 3655 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3656 BaseDeclType = Array->getElementType(); 3657 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3658 diag::err_typecheck_decl_incomplete_type)) { 3659 RealDecl->setInvalidDecl(); 3660 return; 3661 } 3662 3663 // The variable can not have an abstract class type. 3664 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3665 diag::err_abstract_type_in_decl, 3666 AbstractVariableType)) 3667 VDecl->setInvalidDecl(); 3668 3669 const VarDecl *Def; 3670 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3671 Diag(VDecl->getLocation(), diag::err_redefinition) 3672 << VDecl->getDeclName(); 3673 Diag(Def->getLocation(), diag::note_previous_definition); 3674 VDecl->setInvalidDecl(); 3675 return; 3676 } 3677 3678 // Take ownership of the expression, now that we're sure we have somewhere 3679 // to put it. 3680 Expr *Init = init.takeAs<Expr>(); 3681 assert(Init && "missing initializer"); 3682 3683 // Capture the variable that is being initialized and the style of 3684 // initialization. 3685 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3686 3687 // FIXME: Poor source location information. 3688 InitializationKind Kind 3689 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3690 Init->getLocStart(), 3691 Init->getLocEnd()) 3692 : InitializationKind::CreateCopy(VDecl->getLocation(), 3693 Init->getLocStart()); 3694 3695 // Get the decls type and save a reference for later, since 3696 // CheckInitializerTypes may change it. 3697 QualType DclT = VDecl->getType(), SavT = DclT; 3698 if (VDecl->isBlockVarDecl()) { 3699 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3700 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3701 VDecl->setInvalidDecl(); 3702 } else if (!VDecl->isInvalidDecl()) { 3703 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3704 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3705 MultiExprArg(*this, (void**)&Init, 1), 3706 &DclT); 3707 if (Result.isInvalid()) { 3708 VDecl->setInvalidDecl(); 3709 return; 3710 } 3711 3712 Init = Result.takeAs<Expr>(); 3713 3714 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3715 // Don't check invalid declarations to avoid emitting useless diagnostics. 3716 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3717 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3718 CheckForConstantInitializer(Init, DclT); 3719 } 3720 } 3721 } else if (VDecl->isStaticDataMember() && 3722 VDecl->getLexicalDeclContext()->isRecord()) { 3723 // This is an in-class initialization for a static data member, e.g., 3724 // 3725 // struct S { 3726 // static const int value = 17; 3727 // }; 3728 3729 // Attach the initializer 3730 VDecl->setInit(Init); 3731 3732 // C++ [class.mem]p4: 3733 // A member-declarator can contain a constant-initializer only 3734 // if it declares a static member (9.4) of const integral or 3735 // const enumeration type, see 9.4.2. 3736 QualType T = VDecl->getType(); 3737 if (!T->isDependentType() && 3738 (!Context.getCanonicalType(T).isConstQualified() || 3739 !T->isIntegralType())) { 3740 Diag(VDecl->getLocation(), diag::err_member_initialization) 3741 << VDecl->getDeclName() << Init->getSourceRange(); 3742 VDecl->setInvalidDecl(); 3743 } else { 3744 // C++ [class.static.data]p4: 3745 // If a static data member is of const integral or const 3746 // enumeration type, its declaration in the class definition 3747 // can specify a constant-initializer which shall be an 3748 // integral constant expression (5.19). 3749 if (!Init->isTypeDependent() && 3750 !Init->getType()->isIntegralType()) { 3751 // We have a non-dependent, non-integral or enumeration type. 3752 Diag(Init->getSourceRange().getBegin(), 3753 diag::err_in_class_initializer_non_integral_type) 3754 << Init->getType() << Init->getSourceRange(); 3755 VDecl->setInvalidDecl(); 3756 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3757 // Check whether the expression is a constant expression. 3758 llvm::APSInt Value; 3759 SourceLocation Loc; 3760 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3761 Diag(Loc, diag::err_in_class_initializer_non_constant) 3762 << Init->getSourceRange(); 3763 VDecl->setInvalidDecl(); 3764 } else if (!VDecl->getType()->isDependentType()) 3765 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3766 } 3767 } 3768 } else if (VDecl->isFileVarDecl()) { 3769 if (VDecl->getStorageClass() == VarDecl::Extern) 3770 Diag(VDecl->getLocation(), diag::warn_extern_init); 3771 if (!VDecl->isInvalidDecl()) { 3772 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3773 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3774 MultiExprArg(*this, (void**)&Init, 1), 3775 &DclT); 3776 if (Result.isInvalid()) { 3777 VDecl->setInvalidDecl(); 3778 return; 3779 } 3780 3781 Init = Result.takeAs<Expr>(); 3782 } 3783 3784 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3785 // Don't check invalid declarations to avoid emitting useless diagnostics. 3786 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3787 // C99 6.7.8p4. All file scoped initializers need to be constant. 3788 CheckForConstantInitializer(Init, DclT); 3789 } 3790 } 3791 // If the type changed, it means we had an incomplete type that was 3792 // completed by the initializer. For example: 3793 // int ary[] = { 1, 3, 5 }; 3794 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3795 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3796 VDecl->setType(DclT); 3797 Init->setType(DclT); 3798 } 3799 3800 Init = MaybeCreateCXXExprWithTemporaries(Init); 3801 // Attach the initializer to the decl. 3802 VDecl->setInit(Init); 3803 3804 if (getLangOptions().CPlusPlus) { 3805 // Make sure we mark the destructor as used if necessary. 3806 QualType InitType = VDecl->getType(); 3807 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3808 InitType = Context.getBaseElementType(Array); 3809 if (const RecordType *Record = InitType->getAs<RecordType>()) 3810 FinalizeVarWithDestructor(VDecl, Record); 3811 } 3812 3813 return; 3814} 3815 3816/// ActOnInitializerError - Given that there was an error parsing an 3817/// initializer for the given declaration, try to return to some form 3818/// of sanity. 3819void Sema::ActOnInitializerError(DeclPtrTy dcl) { 3820 // Our main concern here is re-establishing invariants like "a 3821 // variable's type is either dependent or complete". 3822 Decl *D = dcl.getAs<Decl>(); 3823 if (!D || D->isInvalidDecl()) return; 3824 3825 VarDecl *VD = dyn_cast<VarDecl>(D); 3826 if (!VD) return; 3827 3828 QualType Ty = VD->getType(); 3829 if (Ty->isDependentType()) return; 3830 3831 // Require a complete type. 3832 if (RequireCompleteType(VD->getLocation(), 3833 Context.getBaseElementType(Ty), 3834 diag::err_typecheck_decl_incomplete_type)) { 3835 VD->setInvalidDecl(); 3836 return; 3837 } 3838 3839 // Require an abstract type. 3840 if (RequireNonAbstractType(VD->getLocation(), Ty, 3841 diag::err_abstract_type_in_decl, 3842 AbstractVariableType)) { 3843 VD->setInvalidDecl(); 3844 return; 3845 } 3846 3847 // Don't bother complaining about constructors or destructors, 3848 // though. 3849} 3850 3851void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3852 bool TypeContainsUndeducedAuto) { 3853 Decl *RealDecl = dcl.getAs<Decl>(); 3854 3855 // If there is no declaration, there was an error parsing it. Just ignore it. 3856 if (RealDecl == 0) 3857 return; 3858 3859 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3860 QualType Type = Var->getType(); 3861 3862 // C++0x [dcl.spec.auto]p3 3863 if (TypeContainsUndeducedAuto) { 3864 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3865 << Var->getDeclName() << Type; 3866 Var->setInvalidDecl(); 3867 return; 3868 } 3869 3870 switch (Var->isThisDeclarationADefinition()) { 3871 case VarDecl::Definition: 3872 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 3873 break; 3874 3875 // We have an out-of-line definition of a static data member 3876 // that has an in-class initializer, so we type-check this like 3877 // a declaration. 3878 // 3879 // Fall through 3880 3881 case VarDecl::DeclarationOnly: 3882 // It's only a declaration. 3883 3884 // Block scope. C99 6.7p7: If an identifier for an object is 3885 // declared with no linkage (C99 6.2.2p6), the type for the 3886 // object shall be complete. 3887 if (!Type->isDependentType() && Var->isBlockVarDecl() && 3888 !Var->getLinkage() && !Var->isInvalidDecl() && 3889 RequireCompleteType(Var->getLocation(), Type, 3890 diag::err_typecheck_decl_incomplete_type)) 3891 Var->setInvalidDecl(); 3892 3893 // Make sure that the type is not abstract. 3894 if (!Type->isDependentType() && !Var->isInvalidDecl() && 3895 RequireNonAbstractType(Var->getLocation(), Type, 3896 diag::err_abstract_type_in_decl, 3897 AbstractVariableType)) 3898 Var->setInvalidDecl(); 3899 return; 3900 3901 case VarDecl::TentativeDefinition: 3902 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3903 // object that has file scope without an initializer, and without a 3904 // storage-class specifier or with the storage-class specifier "static", 3905 // constitutes a tentative definition. Note: A tentative definition with 3906 // external linkage is valid (C99 6.2.2p5). 3907 if (!Var->isInvalidDecl()) { 3908 if (const IncompleteArrayType *ArrayT 3909 = Context.getAsIncompleteArrayType(Type)) { 3910 if (RequireCompleteType(Var->getLocation(), 3911 ArrayT->getElementType(), 3912 diag::err_illegal_decl_array_incomplete_type)) 3913 Var->setInvalidDecl(); 3914 } else if (Var->getStorageClass() == VarDecl::Static) { 3915 // C99 6.9.2p3: If the declaration of an identifier for an object is 3916 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3917 // declared type shall not be an incomplete type. 3918 // NOTE: code such as the following 3919 // static struct s; 3920 // struct s { int a; }; 3921 // is accepted by gcc. Hence here we issue a warning instead of 3922 // an error and we do not invalidate the static declaration. 3923 // NOTE: to avoid multiple warnings, only check the first declaration. 3924 if (Var->getPreviousDeclaration() == 0) 3925 RequireCompleteType(Var->getLocation(), Type, 3926 diag::ext_typecheck_decl_incomplete_type); 3927 } 3928 } 3929 3930 // Record the tentative definition; we're done. 3931 if (!Var->isInvalidDecl()) 3932 TentativeDefinitions.push_back(Var); 3933 return; 3934 } 3935 3936 // Provide a specific diagnostic for uninitialized variable 3937 // definitions with incomplete array type. 3938 if (Type->isIncompleteArrayType()) { 3939 Diag(Var->getLocation(), 3940 diag::err_typecheck_incomplete_array_needs_initializer); 3941 Var->setInvalidDecl(); 3942 return; 3943 } 3944 3945 // Provide a specific diagnostic for uninitialized variable 3946 // definitions with reference type. 3947 if (Type->isReferenceType()) { 3948 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3949 << Var->getDeclName() 3950 << SourceRange(Var->getLocation(), Var->getLocation()); 3951 Var->setInvalidDecl(); 3952 return; 3953 } 3954 3955 // Do not attempt to type-check the default initializer for a 3956 // variable with dependent type. 3957 if (Type->isDependentType()) 3958 return; 3959 3960 if (Var->isInvalidDecl()) 3961 return; 3962 3963 if (RequireCompleteType(Var->getLocation(), 3964 Context.getBaseElementType(Type), 3965 diag::err_typecheck_decl_incomplete_type)) { 3966 Var->setInvalidDecl(); 3967 return; 3968 } 3969 3970 // The variable can not have an abstract class type. 3971 if (RequireNonAbstractType(Var->getLocation(), Type, 3972 diag::err_abstract_type_in_decl, 3973 AbstractVariableType)) { 3974 Var->setInvalidDecl(); 3975 return; 3976 } 3977 3978 const RecordType *Record 3979 = Context.getBaseElementType(Type)->getAs<RecordType>(); 3980 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 3981 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 3982 // C++03 [dcl.init]p9: 3983 // If no initializer is specified for an object, and the 3984 // object is of (possibly cv-qualified) non-POD class type (or 3985 // array thereof), the object shall be default-initialized; if 3986 // the object is of const-qualified type, the underlying class 3987 // type shall have a user-declared default 3988 // constructor. Otherwise, if no initializer is specified for 3989 // a non- static object, the object and its subobjects, if 3990 // any, have an indeterminate initial value); if the object 3991 // or any of its subobjects are of const-qualified type, the 3992 // program is ill-formed. 3993 // FIXME: DPG thinks it is very fishy that C++0x disables this. 3994 } else { 3995 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 3996 InitializationKind Kind 3997 = InitializationKind::CreateDefault(Var->getLocation()); 3998 3999 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4000 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4001 MultiExprArg(*this, 0, 0)); 4002 if (Init.isInvalid()) 4003 Var->setInvalidDecl(); 4004 else if (Init.get()) 4005 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4006 } 4007 4008 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4009 FinalizeVarWithDestructor(Var, Record); 4010 } 4011} 4012 4013Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4014 DeclPtrTy *Group, 4015 unsigned NumDecls) { 4016 llvm::SmallVector<Decl*, 8> Decls; 4017 4018 if (DS.isTypeSpecOwned()) 4019 Decls.push_back((Decl*)DS.getTypeRep()); 4020 4021 for (unsigned i = 0; i != NumDecls; ++i) 4022 if (Decl *D = Group[i].getAs<Decl>()) 4023 Decls.push_back(D); 4024 4025 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4026 Decls.data(), Decls.size())); 4027} 4028 4029 4030/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4031/// to introduce parameters into function prototype scope. 4032Sema::DeclPtrTy 4033Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4034 const DeclSpec &DS = D.getDeclSpec(); 4035 4036 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4037 VarDecl::StorageClass StorageClass = VarDecl::None; 4038 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4039 StorageClass = VarDecl::Register; 4040 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4041 Diag(DS.getStorageClassSpecLoc(), 4042 diag::err_invalid_storage_class_in_func_decl); 4043 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4044 } 4045 4046 if (D.getDeclSpec().isThreadSpecified()) 4047 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4048 4049 DiagnoseFunctionSpecifiers(D); 4050 4051 // Check that there are no default arguments inside the type of this 4052 // parameter (C++ only). 4053 if (getLangOptions().CPlusPlus) 4054 CheckExtraCXXDefaultArguments(D); 4055 4056 TypeSourceInfo *TInfo = 0; 4057 TagDecl *OwnedDecl = 0; 4058 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4059 4060 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4061 // C++ [dcl.fct]p6: 4062 // Types shall not be defined in return or parameter types. 4063 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4064 << Context.getTypeDeclType(OwnedDecl); 4065 } 4066 4067 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4068 IdentifierInfo *II = D.getIdentifier(); 4069 if (II) { 4070 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4071 ForRedeclaration); 4072 LookupName(R, S); 4073 if (R.isSingleResult()) { 4074 NamedDecl *PrevDecl = R.getFoundDecl(); 4075 if (PrevDecl->isTemplateParameter()) { 4076 // Maybe we will complain about the shadowed template parameter. 4077 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4078 // Just pretend that we didn't see the previous declaration. 4079 PrevDecl = 0; 4080 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4081 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4082 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4083 4084 // Recover by removing the name 4085 II = 0; 4086 D.SetIdentifier(0, D.getIdentifierLoc()); 4087 D.setInvalidType(true); 4088 } 4089 } 4090 } 4091 4092 // Parameters can not be abstract class types. 4093 // For record types, this is done by the AbstractClassUsageDiagnoser once 4094 // the class has been completely parsed. 4095 if (!CurContext->isRecord() && 4096 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4097 diag::err_abstract_type_in_decl, 4098 AbstractParamType)) 4099 D.setInvalidType(true); 4100 4101 QualType T = adjustParameterType(parmDeclType); 4102 4103 // Temporarily put parameter variables in the translation unit, not 4104 // the enclosing context. This prevents them from accidentally 4105 // looking like class members in C++. 4106 DeclContext *DC = Context.getTranslationUnitDecl(); 4107 4108 ParmVarDecl *New 4109 = ParmVarDecl::Create(Context, DC, D.getIdentifierLoc(), II, 4110 T, TInfo, StorageClass, 0); 4111 4112 if (D.isInvalidType()) 4113 New->setInvalidDecl(); 4114 4115 // Parameter declarators cannot be interface types. All ObjC objects are 4116 // passed by reference. 4117 if (T->isObjCInterfaceType()) { 4118 Diag(D.getIdentifierLoc(), 4119 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4120 New->setInvalidDecl(); 4121 } 4122 4123 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4124 if (D.getCXXScopeSpec().isSet()) { 4125 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4126 << D.getCXXScopeSpec().getRange(); 4127 New->setInvalidDecl(); 4128 } 4129 4130 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4131 // duration shall not be qualified by an address-space qualifier." 4132 // Since all parameters have automatic store duration, they can not have 4133 // an address space. 4134 if (T.getAddressSpace() != 0) { 4135 Diag(D.getIdentifierLoc(), 4136 diag::err_arg_with_address_space); 4137 New->setInvalidDecl(); 4138 } 4139 4140 4141 // Add the parameter declaration into this scope. 4142 S->AddDecl(DeclPtrTy::make(New)); 4143 if (II) 4144 IdResolver.AddDecl(New); 4145 4146 ProcessDeclAttributes(S, New, D); 4147 4148 if (New->hasAttr<BlocksAttr>()) { 4149 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4150 } 4151 return DeclPtrTy::make(New); 4152} 4153 4154void Sema::ActOnObjCCatchParam(DeclPtrTy D) { 4155 ParmVarDecl *Param = cast<ParmVarDecl>(D.getAs<Decl>()); 4156 Param->setDeclContext(CurContext); 4157} 4158 4159void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4160 SourceLocation LocAfterDecls) { 4161 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4162 "Not a function declarator!"); 4163 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4164 4165 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4166 // for a K&R function. 4167 if (!FTI.hasPrototype) { 4168 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4169 --i; 4170 if (FTI.ArgInfo[i].Param == 0) { 4171 llvm::SmallString<256> Code; 4172 llvm::raw_svector_ostream(Code) << " int " 4173 << FTI.ArgInfo[i].Ident->getName() 4174 << ";\n"; 4175 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4176 << FTI.ArgInfo[i].Ident 4177 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4178 4179 // Implicitly declare the argument as type 'int' for lack of a better 4180 // type. 4181 DeclSpec DS; 4182 const char* PrevSpec; // unused 4183 unsigned DiagID; // unused 4184 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4185 PrevSpec, DiagID); 4186 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4187 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4188 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4189 } 4190 } 4191 } 4192} 4193 4194Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4195 Declarator &D) { 4196 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4197 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4198 "Not a function declarator!"); 4199 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4200 4201 if (FTI.hasPrototype) { 4202 // FIXME: Diagnose arguments without names in C. 4203 } 4204 4205 Scope *ParentScope = FnBodyScope->getParent(); 4206 4207 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4208 MultiTemplateParamsArg(*this), 4209 /*IsFunctionDefinition=*/true); 4210 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4211} 4212 4213static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4214 // Don't warn about invalid declarations. 4215 if (FD->isInvalidDecl()) 4216 return false; 4217 4218 // Or declarations that aren't global. 4219 if (!FD->isGlobal()) 4220 return false; 4221 4222 // Don't warn about C++ member functions. 4223 if (isa<CXXMethodDecl>(FD)) 4224 return false; 4225 4226 // Don't warn about 'main'. 4227 if (FD->isMain()) 4228 return false; 4229 4230 // Don't warn about inline functions. 4231 if (FD->isInlineSpecified()) 4232 return false; 4233 4234 // Don't warn about function templates. 4235 if (FD->getDescribedFunctionTemplate()) 4236 return false; 4237 4238 // Don't warn about function template specializations. 4239 if (FD->isFunctionTemplateSpecialization()) 4240 return false; 4241 4242 bool MissingPrototype = true; 4243 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4244 Prev; Prev = Prev->getPreviousDeclaration()) { 4245 // Ignore any declarations that occur in function or method 4246 // scope, because they aren't visible from the header. 4247 if (Prev->getDeclContext()->isFunctionOrMethod()) 4248 continue; 4249 4250 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4251 break; 4252 } 4253 4254 return MissingPrototype; 4255} 4256 4257Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4258 // Clear the last template instantiation error context. 4259 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4260 4261 if (!D) 4262 return D; 4263 FunctionDecl *FD = 0; 4264 4265 if (FunctionTemplateDecl *FunTmpl 4266 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4267 FD = FunTmpl->getTemplatedDecl(); 4268 else 4269 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4270 4271 // Enter a new function scope 4272 PushFunctionScope(); 4273 4274 // See if this is a redefinition. 4275 // But don't complain if we're in GNU89 mode and the previous definition 4276 // was an extern inline function. 4277 const FunctionDecl *Definition; 4278 if (FD->getBody(Definition) && 4279 !canRedefineFunction(Definition, getLangOptions())) { 4280 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4281 Diag(Definition->getLocation(), diag::note_previous_definition); 4282 } 4283 4284 // Builtin functions cannot be defined. 4285 if (unsigned BuiltinID = FD->getBuiltinID()) { 4286 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4287 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4288 FD->setInvalidDecl(); 4289 } 4290 } 4291 4292 // The return type of a function definition must be complete 4293 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4294 QualType ResultType = FD->getResultType(); 4295 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4296 !FD->isInvalidDecl() && 4297 RequireCompleteType(FD->getLocation(), ResultType, 4298 diag::err_func_def_incomplete_result)) 4299 FD->setInvalidDecl(); 4300 4301 // GNU warning -Wmissing-prototypes: 4302 // Warn if a global function is defined without a previous 4303 // prototype declaration. This warning is issued even if the 4304 // definition itself provides a prototype. The aim is to detect 4305 // global functions that fail to be declared in header files. 4306 if (ShouldWarnAboutMissingPrototype(FD)) 4307 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4308 4309 if (FnBodyScope) 4310 PushDeclContext(FnBodyScope, FD); 4311 4312 // Check the validity of our function parameters 4313 CheckParmsForFunctionDef(FD); 4314 4315 bool ShouldCheckShadow = 4316 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4317 4318 // Introduce our parameters into the function scope 4319 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4320 ParmVarDecl *Param = FD->getParamDecl(p); 4321 Param->setOwningFunction(FD); 4322 4323 // If this has an identifier, add it to the scope stack. 4324 if (Param->getIdentifier() && FnBodyScope) { 4325 if (ShouldCheckShadow) 4326 CheckShadow(FnBodyScope, Param); 4327 4328 PushOnScopeChains(Param, FnBodyScope); 4329 } 4330 } 4331 4332 // Checking attributes of current function definition 4333 // dllimport attribute. 4334 if (FD->getAttr<DLLImportAttr>() && 4335 (!FD->getAttr<DLLExportAttr>())) { 4336 // dllimport attribute cannot be applied to definition. 4337 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4338 Diag(FD->getLocation(), 4339 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4340 << "dllimport"; 4341 FD->setInvalidDecl(); 4342 return DeclPtrTy::make(FD); 4343 } 4344 4345 // Visual C++ appears to not think this is an issue, so only issue 4346 // a warning when Microsoft extensions are disabled. 4347 if (!LangOpts.Microsoft) { 4348 // If a symbol previously declared dllimport is later defined, the 4349 // attribute is ignored in subsequent references, and a warning is 4350 // emitted. 4351 Diag(FD->getLocation(), 4352 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4353 << FD->getNameAsCString() << "dllimport"; 4354 } 4355 } 4356 return DeclPtrTy::make(FD); 4357} 4358 4359Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4360 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4361} 4362 4363Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4364 bool IsInstantiation) { 4365 Decl *dcl = D.getAs<Decl>(); 4366 Stmt *Body = BodyArg.takeAs<Stmt>(); 4367 4368 FunctionDecl *FD = 0; 4369 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4370 if (FunTmpl) 4371 FD = FunTmpl->getTemplatedDecl(); 4372 else 4373 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4374 4375 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4376 4377 if (FD) { 4378 FD->setBody(Body); 4379 if (FD->isMain()) { 4380 // C and C++ allow for main to automagically return 0. 4381 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4382 FD->setHasImplicitReturnZero(true); 4383 WP.disableCheckFallThrough(); 4384 } 4385 4386 if (!FD->isInvalidDecl()) 4387 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4388 4389 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4390 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4391 4392 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4393 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4394 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4395 MD->setBody(Body); 4396 MD->setEndLoc(Body->getLocEnd()); 4397 if (!MD->isInvalidDecl()) 4398 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4399 } else { 4400 Body->Destroy(Context); 4401 return DeclPtrTy(); 4402 } 4403 4404 // Verify and clean out per-function state. 4405 4406 // Check goto/label use. 4407 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4408 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4409 LabelStmt *L = I->second; 4410 4411 // Verify that we have no forward references left. If so, there was a goto 4412 // or address of a label taken, but no definition of it. Label fwd 4413 // definitions are indicated with a null substmt. 4414 if (L->getSubStmt() != 0) 4415 continue; 4416 4417 // Emit error. 4418 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4419 4420 // At this point, we have gotos that use the bogus label. Stitch it into 4421 // the function body so that they aren't leaked and that the AST is well 4422 // formed. 4423 if (Body == 0) { 4424 // The whole function wasn't parsed correctly, just delete this. 4425 L->Destroy(Context); 4426 continue; 4427 } 4428 4429 // Otherwise, the body is valid: we want to stitch the label decl into the 4430 // function somewhere so that it is properly owned and so that the goto 4431 // has a valid target. Do this by creating a new compound stmt with the 4432 // label in it. 4433 4434 // Give the label a sub-statement. 4435 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4436 4437 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4438 cast<CXXTryStmt>(Body)->getTryBlock() : 4439 cast<CompoundStmt>(Body); 4440 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4441 Compound->body_end()); 4442 Elements.push_back(L); 4443 Compound->setStmts(Context, Elements.data(), Elements.size()); 4444 } 4445 4446 if (Body) { 4447 // C++ constructors that have function-try-blocks can't have return 4448 // statements in the handlers of that block. (C++ [except.handle]p14) 4449 // Verify this. 4450 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4451 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4452 4453 // Verify that that gotos and switch cases don't jump into scopes illegally. 4454 // Verify that that gotos and switch cases don't jump into scopes illegally. 4455 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 4456 DiagnoseInvalidJumps(Body); 4457 4458 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4459 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4460 Destructor->getParent()); 4461 4462 // If any errors have occurred, clear out any temporaries that may have 4463 // been leftover. This ensures that these temporaries won't be picked up for 4464 // deletion in some later function. 4465 if (PP.getDiagnostics().hasErrorOccurred()) 4466 ExprTemporaries.clear(); 4467 else if (!isa<FunctionTemplateDecl>(dcl)) { 4468 // Since the body is valid, issue any analysis-based warnings that are 4469 // enabled. 4470 QualType ResultType; 4471 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4472 ResultType = FD->getResultType(); 4473 } 4474 else { 4475 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4476 ResultType = MD->getResultType(); 4477 } 4478 AnalysisWarnings.IssueWarnings(WP, dcl); 4479 } 4480 4481 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4482 } 4483 4484 if (!IsInstantiation) 4485 PopDeclContext(); 4486 4487 PopFunctionOrBlockScope(); 4488 4489 // If any errors have occurred, clear out any temporaries that may have 4490 // been leftover. This ensures that these temporaries won't be picked up for 4491 // deletion in some later function. 4492 if (getDiagnostics().hasErrorOccurred()) 4493 ExprTemporaries.clear(); 4494 4495 return D; 4496} 4497 4498/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4499/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4500NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4501 IdentifierInfo &II, Scope *S) { 4502 // Before we produce a declaration for an implicitly defined 4503 // function, see whether there was a locally-scoped declaration of 4504 // this name as a function or variable. If so, use that 4505 // (non-visible) declaration, and complain about it. 4506 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4507 = LocallyScopedExternalDecls.find(&II); 4508 if (Pos != LocallyScopedExternalDecls.end()) { 4509 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4510 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4511 return Pos->second; 4512 } 4513 4514 // Extension in C99. Legal in C90, but warn about it. 4515 if (II.getName().startswith("__builtin_")) 4516 Diag(Loc, diag::warn_builtin_unknown) << &II; 4517 else if (getLangOptions().C99) 4518 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4519 else 4520 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4521 4522 // Set a Declarator for the implicit definition: int foo(); 4523 const char *Dummy; 4524 DeclSpec DS; 4525 unsigned DiagID; 4526 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4527 Error = Error; // Silence warning. 4528 assert(!Error && "Error setting up implicit decl!"); 4529 Declarator D(DS, Declarator::BlockContext); 4530 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4531 0, 0, false, SourceLocation(), 4532 false, 0,0,0, Loc, Loc, D), 4533 SourceLocation()); 4534 D.SetIdentifier(&II, Loc); 4535 4536 // Insert this function into translation-unit scope. 4537 4538 DeclContext *PrevDC = CurContext; 4539 CurContext = Context.getTranslationUnitDecl(); 4540 4541 FunctionDecl *FD = 4542 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4543 FD->setImplicit(); 4544 4545 CurContext = PrevDC; 4546 4547 AddKnownFunctionAttributes(FD); 4548 4549 return FD; 4550} 4551 4552/// \brief Adds any function attributes that we know a priori based on 4553/// the declaration of this function. 4554/// 4555/// These attributes can apply both to implicitly-declared builtins 4556/// (like __builtin___printf_chk) or to library-declared functions 4557/// like NSLog or printf. 4558void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4559 if (FD->isInvalidDecl()) 4560 return; 4561 4562 // If this is a built-in function, map its builtin attributes to 4563 // actual attributes. 4564 if (unsigned BuiltinID = FD->getBuiltinID()) { 4565 // Handle printf-formatting attributes. 4566 unsigned FormatIdx; 4567 bool HasVAListArg; 4568 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4569 if (!FD->getAttr<FormatAttr>()) 4570 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4571 HasVAListArg ? 0 : FormatIdx+2)); 4572 } 4573 4574 // Mark const if we don't care about errno and that is the only 4575 // thing preventing the function from being const. This allows 4576 // IRgen to use LLVM intrinsics for such functions. 4577 if (!getLangOptions().MathErrno && 4578 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4579 if (!FD->getAttr<ConstAttr>()) 4580 FD->addAttr(::new (Context) ConstAttr()); 4581 } 4582 4583 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4584 FD->setType(Context.getNoReturnType(FD->getType())); 4585 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4586 FD->addAttr(::new (Context) NoThrowAttr()); 4587 if (Context.BuiltinInfo.isConst(BuiltinID)) 4588 FD->addAttr(::new (Context) ConstAttr()); 4589 } 4590 4591 IdentifierInfo *Name = FD->getIdentifier(); 4592 if (!Name) 4593 return; 4594 if ((!getLangOptions().CPlusPlus && 4595 FD->getDeclContext()->isTranslationUnit()) || 4596 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4597 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4598 LinkageSpecDecl::lang_c)) { 4599 // Okay: this could be a libc/libm/Objective-C function we know 4600 // about. 4601 } else 4602 return; 4603 4604 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4605 // FIXME: NSLog and NSLogv should be target specific 4606 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4607 // FIXME: We known better than our headers. 4608 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4609 } else 4610 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4611 Name->isStr("NSLogv") ? 0 : 2)); 4612 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4613 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4614 // target-specific builtins, perhaps? 4615 if (!FD->getAttr<FormatAttr>()) 4616 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4617 Name->isStr("vasprintf") ? 0 : 3)); 4618 } 4619} 4620 4621TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4622 TypeSourceInfo *TInfo) { 4623 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4624 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4625 4626 if (!TInfo) { 4627 assert(D.isInvalidType() && "no declarator info for valid type"); 4628 TInfo = Context.getTrivialTypeSourceInfo(T); 4629 } 4630 4631 // Scope manipulation handled by caller. 4632 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4633 D.getIdentifierLoc(), 4634 D.getIdentifier(), 4635 TInfo); 4636 4637 if (const TagType *TT = T->getAs<TagType>()) { 4638 TagDecl *TD = TT->getDecl(); 4639 4640 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4641 // keep track of the TypedefDecl. 4642 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4643 TD->setTypedefForAnonDecl(NewTD); 4644 } 4645 4646 if (D.isInvalidType()) 4647 NewTD->setInvalidDecl(); 4648 return NewTD; 4649} 4650 4651 4652/// \brief Determine whether a tag with a given kind is acceptable 4653/// as a redeclaration of the given tag declaration. 4654/// 4655/// \returns true if the new tag kind is acceptable, false otherwise. 4656bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4657 TagDecl::TagKind NewTag, 4658 SourceLocation NewTagLoc, 4659 const IdentifierInfo &Name) { 4660 // C++ [dcl.type.elab]p3: 4661 // The class-key or enum keyword present in the 4662 // elaborated-type-specifier shall agree in kind with the 4663 // declaration to which the name in theelaborated-type-specifier 4664 // refers. This rule also applies to the form of 4665 // elaborated-type-specifier that declares a class-name or 4666 // friend class since it can be construed as referring to the 4667 // definition of the class. Thus, in any 4668 // elaborated-type-specifier, the enum keyword shall be used to 4669 // refer to an enumeration (7.2), the union class-keyshall be 4670 // used to refer to a union (clause 9), and either the class or 4671 // struct class-key shall be used to refer to a class (clause 9) 4672 // declared using the class or struct class-key. 4673 TagDecl::TagKind OldTag = Previous->getTagKind(); 4674 if (OldTag == NewTag) 4675 return true; 4676 4677 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4678 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4679 // Warn about the struct/class tag mismatch. 4680 bool isTemplate = false; 4681 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4682 isTemplate = Record->getDescribedClassTemplate(); 4683 4684 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4685 << (NewTag == TagDecl::TK_class) 4686 << isTemplate << &Name 4687 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4688 OldTag == TagDecl::TK_class? "class" : "struct"); 4689 Diag(Previous->getLocation(), diag::note_previous_use); 4690 return true; 4691 } 4692 return false; 4693} 4694 4695/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4696/// former case, Name will be non-null. In the later case, Name will be null. 4697/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4698/// reference/declaration/definition of a tag. 4699Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4700 SourceLocation KWLoc, const CXXScopeSpec &SS, 4701 IdentifierInfo *Name, SourceLocation NameLoc, 4702 AttributeList *Attr, AccessSpecifier AS, 4703 MultiTemplateParamsArg TemplateParameterLists, 4704 bool &OwnedDecl, bool &IsDependent) { 4705 // If this is not a definition, it must have a name. 4706 assert((Name != 0 || TUK == TUK_Definition) && 4707 "Nameless record must be a definition!"); 4708 4709 OwnedDecl = false; 4710 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4711 4712 // FIXME: Check explicit specializations more carefully. 4713 bool isExplicitSpecialization = false; 4714 if (TUK != TUK_Reference) { 4715 if (TemplateParameterList *TemplateParams 4716 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4717 (TemplateParameterList**)TemplateParameterLists.get(), 4718 TemplateParameterLists.size(), 4719 isExplicitSpecialization)) { 4720 if (TemplateParams->size() > 0) { 4721 // This is a declaration or definition of a class template (which may 4722 // be a member of another template). 4723 OwnedDecl = false; 4724 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4725 SS, Name, NameLoc, Attr, 4726 TemplateParams, 4727 AS); 4728 TemplateParameterLists.release(); 4729 return Result.get(); 4730 } else { 4731 // The "template<>" header is extraneous. 4732 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4733 << ElaboratedType::getNameForTagKind(Kind) << Name; 4734 isExplicitSpecialization = true; 4735 } 4736 } 4737 4738 TemplateParameterLists.release(); 4739 } 4740 4741 DeclContext *SearchDC = CurContext; 4742 DeclContext *DC = CurContext; 4743 bool isStdBadAlloc = false; 4744 bool Invalid = false; 4745 4746 RedeclarationKind Redecl = ForRedeclaration; 4747 if (TUK == TUK_Friend || TUK == TUK_Reference) 4748 Redecl = NotForRedeclaration; 4749 4750 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4751 4752 if (Name && SS.isNotEmpty()) { 4753 // We have a nested-name tag ('struct foo::bar'). 4754 4755 // Check for invalid 'foo::'. 4756 if (SS.isInvalid()) { 4757 Name = 0; 4758 goto CreateNewDecl; 4759 } 4760 4761 // If this is a friend or a reference to a class in a dependent 4762 // context, don't try to make a decl for it. 4763 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4764 DC = computeDeclContext(SS, false); 4765 if (!DC) { 4766 IsDependent = true; 4767 return DeclPtrTy(); 4768 } 4769 } 4770 4771 if (RequireCompleteDeclContext(SS)) 4772 return DeclPtrTy::make((Decl *)0); 4773 4774 DC = computeDeclContext(SS, true); 4775 SearchDC = DC; 4776 // Look-up name inside 'foo::'. 4777 LookupQualifiedName(Previous, DC); 4778 4779 if (Previous.isAmbiguous()) 4780 return DeclPtrTy(); 4781 4782 if (Previous.empty()) { 4783 // Name lookup did not find anything. However, if the 4784 // nested-name-specifier refers to the current instantiation, 4785 // and that current instantiation has any dependent base 4786 // classes, we might find something at instantiation time: treat 4787 // this as a dependent elaborated-type-specifier. 4788 if (Previous.wasNotFoundInCurrentInstantiation()) { 4789 IsDependent = true; 4790 return DeclPtrTy(); 4791 } 4792 4793 // A tag 'foo::bar' must already exist. 4794 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4795 Name = 0; 4796 Invalid = true; 4797 goto CreateNewDecl; 4798 } 4799 } else if (Name) { 4800 // If this is a named struct, check to see if there was a previous forward 4801 // declaration or definition. 4802 // FIXME: We're looking into outer scopes here, even when we 4803 // shouldn't be. Doing so can result in ambiguities that we 4804 // shouldn't be diagnosing. 4805 LookupName(Previous, S); 4806 4807 // Note: there used to be some attempt at recovery here. 4808 if (Previous.isAmbiguous()) 4809 return DeclPtrTy(); 4810 4811 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4812 // FIXME: This makes sure that we ignore the contexts associated 4813 // with C structs, unions, and enums when looking for a matching 4814 // tag declaration or definition. See the similar lookup tweak 4815 // in Sema::LookupName; is there a better way to deal with this? 4816 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4817 SearchDC = SearchDC->getParent(); 4818 } 4819 } 4820 4821 if (Previous.isSingleResult() && 4822 Previous.getFoundDecl()->isTemplateParameter()) { 4823 // Maybe we will complain about the shadowed template parameter. 4824 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4825 // Just pretend that we didn't see the previous declaration. 4826 Previous.clear(); 4827 } 4828 4829 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4830 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4831 // This is a declaration of or a reference to "std::bad_alloc". 4832 isStdBadAlloc = true; 4833 4834 if (Previous.empty() && StdBadAlloc) { 4835 // std::bad_alloc has been implicitly declared (but made invisible to 4836 // name lookup). Fill in this implicit declaration as the previous 4837 // declaration, so that the declarations get chained appropriately. 4838 Previous.addDecl(StdBadAlloc); 4839 } 4840 } 4841 4842 // If we didn't find a previous declaration, and this is a reference 4843 // (or friend reference), move to the correct scope. In C++, we 4844 // also need to do a redeclaration lookup there, just in case 4845 // there's a shadow friend decl. 4846 if (Name && Previous.empty() && 4847 (TUK == TUK_Reference || TUK == TUK_Friend)) { 4848 if (Invalid) goto CreateNewDecl; 4849 assert(SS.isEmpty()); 4850 4851 if (TUK == TUK_Reference) { 4852 // C++ [basic.scope.pdecl]p5: 4853 // -- for an elaborated-type-specifier of the form 4854 // 4855 // class-key identifier 4856 // 4857 // if the elaborated-type-specifier is used in the 4858 // decl-specifier-seq or parameter-declaration-clause of a 4859 // function defined in namespace scope, the identifier is 4860 // declared as a class-name in the namespace that contains 4861 // the declaration; otherwise, except as a friend 4862 // declaration, the identifier is declared in the smallest 4863 // non-class, non-function-prototype scope that contains the 4864 // declaration. 4865 // 4866 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4867 // C structs and unions. 4868 // 4869 // It is an error in C++ to declare (rather than define) an enum 4870 // type, including via an elaborated type specifier. We'll 4871 // diagnose that later; for now, declare the enum in the same 4872 // scope as we would have picked for any other tag type. 4873 // 4874 // GNU C also supports this behavior as part of its incomplete 4875 // enum types extension, while GNU C++ does not. 4876 // 4877 // Find the context where we'll be declaring the tag. 4878 // FIXME: We would like to maintain the current DeclContext as the 4879 // lexical context, 4880 while (SearchDC->isRecord()) 4881 SearchDC = SearchDC->getParent(); 4882 4883 // Find the scope where we'll be declaring the tag. 4884 while (S->isClassScope() || 4885 (getLangOptions().CPlusPlus && 4886 S->isFunctionPrototypeScope()) || 4887 ((S->getFlags() & Scope::DeclScope) == 0) || 4888 (S->getEntity() && 4889 ((DeclContext *)S->getEntity())->isTransparentContext())) 4890 S = S->getParent(); 4891 } else { 4892 assert(TUK == TUK_Friend); 4893 // C++ [namespace.memdef]p3: 4894 // If a friend declaration in a non-local class first declares a 4895 // class or function, the friend class or function is a member of 4896 // the innermost enclosing namespace. 4897 SearchDC = SearchDC->getEnclosingNamespaceContext(); 4898 4899 // Look up through our scopes until we find one with an entity which 4900 // matches our declaration context. 4901 while (S->getEntity() && 4902 ((DeclContext *)S->getEntity())->getPrimaryContext() != SearchDC) { 4903 S = S->getParent(); 4904 assert(S && "No enclosing scope matching the enclosing namespace."); 4905 } 4906 } 4907 4908 // In C++, look for a shadow friend decl. 4909 if (getLangOptions().CPlusPlus) { 4910 Previous.setRedeclarationKind(ForRedeclaration); 4911 LookupQualifiedName(Previous, SearchDC); 4912 } 4913 } 4914 4915 if (!Previous.empty()) { 4916 assert(Previous.isSingleResult()); 4917 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4918 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4919 // If this is a use of a previous tag, or if the tag is already declared 4920 // in the same scope (so that the definition/declaration completes or 4921 // rementions the tag), reuse the decl. 4922 if (TUK == TUK_Reference || TUK == TUK_Friend || 4923 isDeclInScope(PrevDecl, SearchDC, S)) { 4924 // Make sure that this wasn't declared as an enum and now used as a 4925 // struct or something similar. 4926 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4927 bool SafeToContinue 4928 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4929 Kind != TagDecl::TK_enum); 4930 if (SafeToContinue) 4931 Diag(KWLoc, diag::err_use_with_wrong_tag) 4932 << Name 4933 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4934 PrevTagDecl->getKindName()); 4935 else 4936 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4937 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4938 4939 if (SafeToContinue) 4940 Kind = PrevTagDecl->getTagKind(); 4941 else { 4942 // Recover by making this an anonymous redefinition. 4943 Name = 0; 4944 Previous.clear(); 4945 Invalid = true; 4946 } 4947 } 4948 4949 if (!Invalid) { 4950 // If this is a use, just return the declaration we found. 4951 4952 // FIXME: In the future, return a variant or some other clue 4953 // for the consumer of this Decl to know it doesn't own it. 4954 // For our current ASTs this shouldn't be a problem, but will 4955 // need to be changed with DeclGroups. 4956 if (TUK == TUK_Reference || TUK == TUK_Friend) 4957 return DeclPtrTy::make(PrevTagDecl); 4958 4959 // Diagnose attempts to redefine a tag. 4960 if (TUK == TUK_Definition) { 4961 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 4962 // If we're defining a specialization and the previous definition 4963 // is from an implicit instantiation, don't emit an error 4964 // here; we'll catch this in the general case below. 4965 if (!isExplicitSpecialization || 4966 !isa<CXXRecordDecl>(Def) || 4967 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4968 == TSK_ExplicitSpecialization) { 4969 Diag(NameLoc, diag::err_redefinition) << Name; 4970 Diag(Def->getLocation(), diag::note_previous_definition); 4971 // If this is a redefinition, recover by making this 4972 // struct be anonymous, which will make any later 4973 // references get the previous definition. 4974 Name = 0; 4975 Previous.clear(); 4976 Invalid = true; 4977 } 4978 } else { 4979 // If the type is currently being defined, complain 4980 // about a nested redefinition. 4981 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4982 if (Tag->isBeingDefined()) { 4983 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4984 Diag(PrevTagDecl->getLocation(), 4985 diag::note_previous_definition); 4986 Name = 0; 4987 Previous.clear(); 4988 Invalid = true; 4989 } 4990 } 4991 4992 // Okay, this is definition of a previously declared or referenced 4993 // tag PrevDecl. We're going to create a new Decl for it. 4994 } 4995 } 4996 // If we get here we have (another) forward declaration or we 4997 // have a definition. Just create a new decl. 4998 4999 } else { 5000 // If we get here, this is a definition of a new tag type in a nested 5001 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5002 // new decl/type. We set PrevDecl to NULL so that the entities 5003 // have distinct types. 5004 Previous.clear(); 5005 } 5006 // If we get here, we're going to create a new Decl. If PrevDecl 5007 // is non-NULL, it's a definition of the tag declared by 5008 // PrevDecl. If it's NULL, we have a new definition. 5009 } else { 5010 // PrevDecl is a namespace, template, or anything else 5011 // that lives in the IDNS_Tag identifier namespace. 5012 if (TUK == TUK_Reference || TUK == TUK_Friend || 5013 isDeclInScope(PrevDecl, SearchDC, S)) { 5014 // The tag name clashes with a namespace name, issue an error and 5015 // recover by making this tag be anonymous. 5016 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5017 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5018 Name = 0; 5019 Previous.clear(); 5020 Invalid = true; 5021 } else { 5022 // The existing declaration isn't relevant to us; we're in a 5023 // new scope, so clear out the previous declaration. 5024 Previous.clear(); 5025 } 5026 } 5027 } 5028 5029CreateNewDecl: 5030 5031 TagDecl *PrevDecl = 0; 5032 if (Previous.isSingleResult()) 5033 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5034 5035 // If there is an identifier, use the location of the identifier as the 5036 // location of the decl, otherwise use the location of the struct/union 5037 // keyword. 5038 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5039 5040 // Otherwise, create a new declaration. If there is a previous 5041 // declaration of the same entity, the two will be linked via 5042 // PrevDecl. 5043 TagDecl *New; 5044 5045 if (Kind == TagDecl::TK_enum) { 5046 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5047 // enum X { A, B, C } D; D should chain to X. 5048 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5049 cast_or_null<EnumDecl>(PrevDecl)); 5050 // If this is an undefined enum, warn. 5051 if (TUK != TUK_Definition && !Invalid) { 5052 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5053 : diag::ext_forward_ref_enum; 5054 Diag(Loc, DK); 5055 } 5056 } else { 5057 // struct/union/class 5058 5059 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5060 // struct X { int A; } D; D should chain to X. 5061 if (getLangOptions().CPlusPlus) { 5062 // FIXME: Look for a way to use RecordDecl for simple structs. 5063 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5064 cast_or_null<CXXRecordDecl>(PrevDecl)); 5065 5066 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5067 StdBadAlloc = cast<CXXRecordDecl>(New); 5068 } else 5069 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5070 cast_or_null<RecordDecl>(PrevDecl)); 5071 } 5072 5073 // Maybe add qualifier info. 5074 if (SS.isNotEmpty()) { 5075 NestedNameSpecifier *NNS 5076 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5077 New->setQualifierInfo(NNS, SS.getRange()); 5078 } 5079 5080 if (Kind != TagDecl::TK_enum) { 5081 // Handle #pragma pack: if the #pragma pack stack has non-default 5082 // alignment, make up a packed attribute for this decl. These 5083 // attributes are checked when the ASTContext lays out the 5084 // structure. 5085 // 5086 // It is important for implementing the correct semantics that this 5087 // happen here (in act on tag decl). The #pragma pack stack is 5088 // maintained as a result of parser callbacks which can occur at 5089 // many points during the parsing of a struct declaration (because 5090 // the #pragma tokens are effectively skipped over during the 5091 // parsing of the struct). 5092 if (unsigned Alignment = getPragmaPackAlignment()) 5093 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5094 } 5095 5096 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5097 // C++ [dcl.typedef]p3: 5098 // [...] Similarly, in a given scope, a class or enumeration 5099 // shall not be declared with the same name as a typedef-name 5100 // that is declared in that scope and refers to a type other 5101 // than the class or enumeration itself. 5102 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5103 ForRedeclaration); 5104 LookupName(Lookup, S); 5105 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5106 NamedDecl *PrevTypedefNamed = PrevTypedef; 5107 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5108 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5109 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5110 Diag(Loc, diag::err_tag_definition_of_typedef) 5111 << Context.getTypeDeclType(New) 5112 << PrevTypedef->getUnderlyingType(); 5113 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5114 Invalid = true; 5115 } 5116 } 5117 5118 // If this is a specialization of a member class (of a class template), 5119 // check the specialization. 5120 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5121 Invalid = true; 5122 5123 if (Invalid) 5124 New->setInvalidDecl(); 5125 5126 if (Attr) 5127 ProcessDeclAttributeList(S, New, Attr); 5128 5129 // If we're declaring or defining a tag in function prototype scope 5130 // in C, note that this type can only be used within the function. 5131 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5132 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5133 5134 // Set the lexical context. If the tag has a C++ scope specifier, the 5135 // lexical context will be different from the semantic context. 5136 New->setLexicalDeclContext(CurContext); 5137 5138 // Mark this as a friend decl if applicable. 5139 if (TUK == TUK_Friend) 5140 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5141 5142 // Set the access specifier. 5143 if (!Invalid && SearchDC->isRecord()) 5144 SetMemberAccessSpecifier(New, PrevDecl, AS); 5145 5146 if (TUK == TUK_Definition) 5147 New->startDefinition(); 5148 5149 // If this has an identifier, add it to the scope stack. 5150 if (TUK == TUK_Friend) { 5151 // We might be replacing an existing declaration in the lookup tables; 5152 // if so, borrow its access specifier. 5153 if (PrevDecl) 5154 New->setAccess(PrevDecl->getAccess()); 5155 5156 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5157 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5158 if (Name) // can be null along some error paths 5159 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5160 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5161 } else if (Name) { 5162 S = getNonFieldDeclScope(S); 5163 PushOnScopeChains(New, S); 5164 } else { 5165 CurContext->addDecl(New); 5166 } 5167 5168 // If this is the C FILE type, notify the AST context. 5169 if (IdentifierInfo *II = New->getIdentifier()) 5170 if (!New->isInvalidDecl() && 5171 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5172 II->isStr("FILE")) 5173 Context.setFILEDecl(New); 5174 5175 OwnedDecl = true; 5176 return DeclPtrTy::make(New); 5177} 5178 5179void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5180 AdjustDeclIfTemplate(TagD); 5181 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5182 5183 // Enter the tag context. 5184 PushDeclContext(S, Tag); 5185} 5186 5187void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5188 SourceLocation LBraceLoc) { 5189 AdjustDeclIfTemplate(TagD); 5190 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5191 5192 FieldCollector->StartClass(); 5193 5194 if (!Record->getIdentifier()) 5195 return; 5196 5197 // C++ [class]p2: 5198 // [...] The class-name is also inserted into the scope of the 5199 // class itself; this is known as the injected-class-name. For 5200 // purposes of access checking, the injected-class-name is treated 5201 // as if it were a public member name. 5202 CXXRecordDecl *InjectedClassName 5203 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5204 CurContext, Record->getLocation(), 5205 Record->getIdentifier(), 5206 Record->getTagKeywordLoc(), 5207 Record); 5208 InjectedClassName->setImplicit(); 5209 InjectedClassName->setAccess(AS_public); 5210 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5211 InjectedClassName->setDescribedClassTemplate(Template); 5212 PushOnScopeChains(InjectedClassName, S); 5213 assert(InjectedClassName->isInjectedClassName() && 5214 "Broken injected-class-name"); 5215} 5216 5217// Traverses the class and any nested classes, making a note of any 5218// dynamic classes that have no key function so that we can mark all of 5219// their virtual member functions as "used" at the end of the translation 5220// unit. This ensures that all functions needed by the vtable will get 5221// instantiated/synthesized. 5222static void 5223RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5224 SourceLocation Loc) { 5225 // We don't look at dependent or undefined classes. 5226 if (Record->isDependentContext() || !Record->isDefinition()) 5227 return; 5228 5229 if (Record->isDynamicClass()) { 5230 const CXXMethodDecl *KeyFunction = S.Context.getKeyFunction(Record); 5231 5232 if (!KeyFunction) 5233 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, 5234 Loc)); 5235 5236 if ((!KeyFunction || (KeyFunction->getBody() && KeyFunction->isInlined())) 5237 && Record->getLinkage() == ExternalLinkage) 5238 S.Diag(Record->getLocation(), diag::warn_weak_vtable) << Record; 5239 } 5240 for (DeclContext::decl_iterator D = Record->decls_begin(), 5241 DEnd = Record->decls_end(); 5242 D != DEnd; ++D) { 5243 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5244 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5245 } 5246} 5247 5248void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5249 SourceLocation RBraceLoc) { 5250 AdjustDeclIfTemplate(TagD); 5251 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5252 Tag->setRBraceLoc(RBraceLoc); 5253 5254 if (isa<CXXRecordDecl>(Tag)) 5255 FieldCollector->FinishClass(); 5256 5257 // Exit this scope of this tag's definition. 5258 PopDeclContext(); 5259 5260 if (isa<CXXRecordDecl>(Tag) && !Tag->getLexicalDeclContext()->isRecord()) 5261 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5262 RBraceLoc); 5263 5264 // Notify the consumer that we've defined a tag. 5265 Consumer.HandleTagDeclDefinition(Tag); 5266} 5267 5268void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5269 AdjustDeclIfTemplate(TagD); 5270 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5271 Tag->setInvalidDecl(); 5272 5273 // We're undoing ActOnTagStartDefinition here, not 5274 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5275 // the FieldCollector. 5276 5277 PopDeclContext(); 5278} 5279 5280// Note that FieldName may be null for anonymous bitfields. 5281bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5282 QualType FieldTy, const Expr *BitWidth, 5283 bool *ZeroWidth) { 5284 // Default to true; that shouldn't confuse checks for emptiness 5285 if (ZeroWidth) 5286 *ZeroWidth = true; 5287 5288 // C99 6.7.2.1p4 - verify the field type. 5289 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5290 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5291 // Handle incomplete types with specific error. 5292 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5293 return true; 5294 if (FieldName) 5295 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5296 << FieldName << FieldTy << BitWidth->getSourceRange(); 5297 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5298 << FieldTy << BitWidth->getSourceRange(); 5299 } 5300 5301 // If the bit-width is type- or value-dependent, don't try to check 5302 // it now. 5303 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5304 return false; 5305 5306 llvm::APSInt Value; 5307 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5308 return true; 5309 5310 if (Value != 0 && ZeroWidth) 5311 *ZeroWidth = false; 5312 5313 // Zero-width bitfield is ok for anonymous field. 5314 if (Value == 0 && FieldName) 5315 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5316 5317 if (Value.isSigned() && Value.isNegative()) { 5318 if (FieldName) 5319 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5320 << FieldName << Value.toString(10); 5321 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5322 << Value.toString(10); 5323 } 5324 5325 if (!FieldTy->isDependentType()) { 5326 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5327 if (Value.getZExtValue() > TypeSize) { 5328 if (FieldName) 5329 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5330 << FieldName << (unsigned)TypeSize; 5331 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5332 << (unsigned)TypeSize; 5333 } 5334 } 5335 5336 return false; 5337} 5338 5339/// ActOnField - Each field of a struct/union/class is passed into this in order 5340/// to create a FieldDecl object for it. 5341Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5342 SourceLocation DeclStart, 5343 Declarator &D, ExprTy *BitfieldWidth) { 5344 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5345 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5346 AS_public); 5347 return DeclPtrTy::make(Res); 5348} 5349 5350/// HandleField - Analyze a field of a C struct or a C++ data member. 5351/// 5352FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5353 SourceLocation DeclStart, 5354 Declarator &D, Expr *BitWidth, 5355 AccessSpecifier AS) { 5356 IdentifierInfo *II = D.getIdentifier(); 5357 SourceLocation Loc = DeclStart; 5358 if (II) Loc = D.getIdentifierLoc(); 5359 5360 TypeSourceInfo *TInfo = 0; 5361 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5362 if (getLangOptions().CPlusPlus) 5363 CheckExtraCXXDefaultArguments(D); 5364 5365 DiagnoseFunctionSpecifiers(D); 5366 5367 if (D.getDeclSpec().isThreadSpecified()) 5368 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5369 5370 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5371 ForRedeclaration); 5372 5373 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5374 // Maybe we will complain about the shadowed template parameter. 5375 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5376 // Just pretend that we didn't see the previous declaration. 5377 PrevDecl = 0; 5378 } 5379 5380 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5381 PrevDecl = 0; 5382 5383 bool Mutable 5384 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5385 SourceLocation TSSL = D.getSourceRange().getBegin(); 5386 FieldDecl *NewFD 5387 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5388 AS, PrevDecl, &D); 5389 5390 if (NewFD->isInvalidDecl()) 5391 Record->setInvalidDecl(); 5392 5393 if (NewFD->isInvalidDecl() && PrevDecl) { 5394 // Don't introduce NewFD into scope; there's already something 5395 // with the same name in the same scope. 5396 } else if (II) { 5397 PushOnScopeChains(NewFD, S); 5398 } else 5399 Record->addDecl(NewFD); 5400 5401 return NewFD; 5402} 5403 5404/// \brief Build a new FieldDecl and check its well-formedness. 5405/// 5406/// This routine builds a new FieldDecl given the fields name, type, 5407/// record, etc. \p PrevDecl should refer to any previous declaration 5408/// with the same name and in the same scope as the field to be 5409/// created. 5410/// 5411/// \returns a new FieldDecl. 5412/// 5413/// \todo The Declarator argument is a hack. It will be removed once 5414FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5415 TypeSourceInfo *TInfo, 5416 RecordDecl *Record, SourceLocation Loc, 5417 bool Mutable, Expr *BitWidth, 5418 SourceLocation TSSL, 5419 AccessSpecifier AS, NamedDecl *PrevDecl, 5420 Declarator *D) { 5421 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5422 bool InvalidDecl = false; 5423 if (D) InvalidDecl = D->isInvalidType(); 5424 5425 // If we receive a broken type, recover by assuming 'int' and 5426 // marking this declaration as invalid. 5427 if (T.isNull()) { 5428 InvalidDecl = true; 5429 T = Context.IntTy; 5430 } 5431 5432 QualType EltTy = Context.getBaseElementType(T); 5433 if (!EltTy->isDependentType() && 5434 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5435 InvalidDecl = true; 5436 5437 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5438 // than a variably modified type. 5439 if (!InvalidDecl && T->isVariablyModifiedType()) { 5440 bool SizeIsNegative; 5441 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5442 SizeIsNegative); 5443 if (!FixedTy.isNull()) { 5444 Diag(Loc, diag::warn_illegal_constant_array_size); 5445 T = FixedTy; 5446 } else { 5447 if (SizeIsNegative) 5448 Diag(Loc, diag::err_typecheck_negative_array_size); 5449 else 5450 Diag(Loc, diag::err_typecheck_field_variable_size); 5451 InvalidDecl = true; 5452 } 5453 } 5454 5455 // Fields can not have abstract class types 5456 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5457 diag::err_abstract_type_in_decl, 5458 AbstractFieldType)) 5459 InvalidDecl = true; 5460 5461 bool ZeroWidth = false; 5462 // If this is declared as a bit-field, check the bit-field. 5463 if (!InvalidDecl && BitWidth && 5464 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5465 InvalidDecl = true; 5466 DeleteExpr(BitWidth); 5467 BitWidth = 0; 5468 ZeroWidth = false; 5469 } 5470 5471 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5472 BitWidth, Mutable); 5473 if (InvalidDecl) 5474 NewFD->setInvalidDecl(); 5475 5476 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5477 Diag(Loc, diag::err_duplicate_member) << II; 5478 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5479 NewFD->setInvalidDecl(); 5480 } 5481 5482 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5483 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5484 5485 if (!T->isPODType()) 5486 CXXRecord->setPOD(false); 5487 if (!ZeroWidth) 5488 CXXRecord->setEmpty(false); 5489 5490 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5491 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5492 5493 if (!RDecl->hasTrivialConstructor()) 5494 CXXRecord->setHasTrivialConstructor(false); 5495 if (!RDecl->hasTrivialCopyConstructor()) 5496 CXXRecord->setHasTrivialCopyConstructor(false); 5497 if (!RDecl->hasTrivialCopyAssignment()) 5498 CXXRecord->setHasTrivialCopyAssignment(false); 5499 if (!RDecl->hasTrivialDestructor()) 5500 CXXRecord->setHasTrivialDestructor(false); 5501 5502 // C++ 9.5p1: An object of a class with a non-trivial 5503 // constructor, a non-trivial copy constructor, a non-trivial 5504 // destructor, or a non-trivial copy assignment operator 5505 // cannot be a member of a union, nor can an array of such 5506 // objects. 5507 // TODO: C++0x alters this restriction significantly. 5508 if (Record->isUnion()) { 5509 // We check for copy constructors before constructors 5510 // because otherwise we'll never get complaints about 5511 // copy constructors. 5512 5513 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5514 5515 CXXSpecialMember member; 5516 if (!RDecl->hasTrivialCopyConstructor()) 5517 member = CXXCopyConstructor; 5518 else if (!RDecl->hasTrivialConstructor()) 5519 member = CXXDefaultConstructor; 5520 else if (!RDecl->hasTrivialCopyAssignment()) 5521 member = CXXCopyAssignment; 5522 else if (!RDecl->hasTrivialDestructor()) 5523 member = CXXDestructor; 5524 else 5525 member = invalid; 5526 5527 if (member != invalid) { 5528 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5529 DiagnoseNontrivial(RT, member); 5530 NewFD->setInvalidDecl(); 5531 } 5532 } 5533 } 5534 } 5535 5536 // FIXME: We need to pass in the attributes given an AST 5537 // representation, not a parser representation. 5538 if (D) 5539 // FIXME: What to pass instead of TUScope? 5540 ProcessDeclAttributes(TUScope, NewFD, *D); 5541 5542 if (T.isObjCGCWeak()) 5543 Diag(Loc, diag::warn_attribute_weak_on_field); 5544 5545 NewFD->setAccess(AS); 5546 5547 // C++ [dcl.init.aggr]p1: 5548 // An aggregate is an array or a class (clause 9) with [...] no 5549 // private or protected non-static data members (clause 11). 5550 // A POD must be an aggregate. 5551 if (getLangOptions().CPlusPlus && 5552 (AS == AS_private || AS == AS_protected)) { 5553 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5554 CXXRecord->setAggregate(false); 5555 CXXRecord->setPOD(false); 5556 } 5557 5558 return NewFD; 5559} 5560 5561/// DiagnoseNontrivial - Given that a class has a non-trivial 5562/// special member, figure out why. 5563void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5564 QualType QT(T, 0U); 5565 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5566 5567 // Check whether the member was user-declared. 5568 switch (member) { 5569 case CXXDefaultConstructor: 5570 if (RD->hasUserDeclaredConstructor()) { 5571 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5572 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5573 const FunctionDecl *body = 0; 5574 ci->getBody(body); 5575 if (!body || 5576 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5577 SourceLocation CtorLoc = ci->getLocation(); 5578 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5579 return; 5580 } 5581 } 5582 5583 assert(0 && "found no user-declared constructors"); 5584 return; 5585 } 5586 break; 5587 5588 case CXXCopyConstructor: 5589 if (RD->hasUserDeclaredCopyConstructor()) { 5590 SourceLocation CtorLoc = 5591 RD->getCopyConstructor(Context, 0)->getLocation(); 5592 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5593 return; 5594 } 5595 break; 5596 5597 case CXXCopyAssignment: 5598 if (RD->hasUserDeclaredCopyAssignment()) { 5599 // FIXME: this should use the location of the copy 5600 // assignment, not the type. 5601 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5602 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5603 return; 5604 } 5605 break; 5606 5607 case CXXDestructor: 5608 if (RD->hasUserDeclaredDestructor()) { 5609 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5610 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5611 return; 5612 } 5613 break; 5614 } 5615 5616 typedef CXXRecordDecl::base_class_iterator base_iter; 5617 5618 // Virtual bases and members inhibit trivial copying/construction, 5619 // but not trivial destruction. 5620 if (member != CXXDestructor) { 5621 // Check for virtual bases. vbases includes indirect virtual bases, 5622 // so we just iterate through the direct bases. 5623 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5624 if (bi->isVirtual()) { 5625 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5626 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5627 return; 5628 } 5629 5630 // Check for virtual methods. 5631 typedef CXXRecordDecl::method_iterator meth_iter; 5632 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5633 ++mi) { 5634 if (mi->isVirtual()) { 5635 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5636 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5637 return; 5638 } 5639 } 5640 } 5641 5642 bool (CXXRecordDecl::*hasTrivial)() const; 5643 switch (member) { 5644 case CXXDefaultConstructor: 5645 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5646 case CXXCopyConstructor: 5647 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5648 case CXXCopyAssignment: 5649 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5650 case CXXDestructor: 5651 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5652 default: 5653 assert(0 && "unexpected special member"); return; 5654 } 5655 5656 // Check for nontrivial bases (and recurse). 5657 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5658 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5659 assert(BaseRT && "Don't know how to handle dependent bases"); 5660 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5661 if (!(BaseRecTy->*hasTrivial)()) { 5662 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5663 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5664 DiagnoseNontrivial(BaseRT, member); 5665 return; 5666 } 5667 } 5668 5669 // Check for nontrivial members (and recurse). 5670 typedef RecordDecl::field_iterator field_iter; 5671 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5672 ++fi) { 5673 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5674 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5675 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5676 5677 if (!(EltRD->*hasTrivial)()) { 5678 SourceLocation FLoc = (*fi)->getLocation(); 5679 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5680 DiagnoseNontrivial(EltRT, member); 5681 return; 5682 } 5683 } 5684 } 5685 5686 assert(0 && "found no explanation for non-trivial member"); 5687} 5688 5689/// TranslateIvarVisibility - Translate visibility from a token ID to an 5690/// AST enum value. 5691static ObjCIvarDecl::AccessControl 5692TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5693 switch (ivarVisibility) { 5694 default: assert(0 && "Unknown visitibility kind"); 5695 case tok::objc_private: return ObjCIvarDecl::Private; 5696 case tok::objc_public: return ObjCIvarDecl::Public; 5697 case tok::objc_protected: return ObjCIvarDecl::Protected; 5698 case tok::objc_package: return ObjCIvarDecl::Package; 5699 } 5700} 5701 5702/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5703/// in order to create an IvarDecl object for it. 5704Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5705 SourceLocation DeclStart, 5706 DeclPtrTy IntfDecl, 5707 Declarator &D, ExprTy *BitfieldWidth, 5708 tok::ObjCKeywordKind Visibility) { 5709 5710 IdentifierInfo *II = D.getIdentifier(); 5711 Expr *BitWidth = (Expr*)BitfieldWidth; 5712 SourceLocation Loc = DeclStart; 5713 if (II) Loc = D.getIdentifierLoc(); 5714 5715 // FIXME: Unnamed fields can be handled in various different ways, for 5716 // example, unnamed unions inject all members into the struct namespace! 5717 5718 TypeSourceInfo *TInfo = 0; 5719 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5720 5721 if (BitWidth) { 5722 // 6.7.2.1p3, 6.7.2.1p4 5723 if (VerifyBitField(Loc, II, T, BitWidth)) { 5724 D.setInvalidType(); 5725 DeleteExpr(BitWidth); 5726 BitWidth = 0; 5727 } 5728 } else { 5729 // Not a bitfield. 5730 5731 // validate II. 5732 5733 } 5734 5735 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5736 // than a variably modified type. 5737 if (T->isVariablyModifiedType()) { 5738 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5739 D.setInvalidType(); 5740 } 5741 5742 // Get the visibility (access control) for this ivar. 5743 ObjCIvarDecl::AccessControl ac = 5744 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5745 : ObjCIvarDecl::None; 5746 // Must set ivar's DeclContext to its enclosing interface. 5747 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5748 DeclContext *EnclosingContext; 5749 if (ObjCImplementationDecl *IMPDecl = 5750 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5751 // Case of ivar declared in an implementation. Context is that of its class. 5752 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5753 assert(IDecl && "No class- ActOnIvar"); 5754 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5755 } else 5756 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5757 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5758 5759 // Construct the decl. 5760 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5761 EnclosingContext, Loc, II, T, 5762 TInfo, ac, (Expr *)BitfieldWidth); 5763 5764 if (II) { 5765 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5766 ForRedeclaration); 5767 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5768 && !isa<TagDecl>(PrevDecl)) { 5769 Diag(Loc, diag::err_duplicate_member) << II; 5770 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5771 NewID->setInvalidDecl(); 5772 } 5773 } 5774 5775 // Process attributes attached to the ivar. 5776 ProcessDeclAttributes(S, NewID, D); 5777 5778 if (D.isInvalidType()) 5779 NewID->setInvalidDecl(); 5780 5781 if (II) { 5782 // FIXME: When interfaces are DeclContexts, we'll need to add 5783 // these to the interface. 5784 S->AddDecl(DeclPtrTy::make(NewID)); 5785 IdResolver.AddDecl(NewID); 5786 } 5787 5788 return DeclPtrTy::make(NewID); 5789} 5790 5791void Sema::ActOnFields(Scope* S, 5792 SourceLocation RecLoc, DeclPtrTy RecDecl, 5793 DeclPtrTy *Fields, unsigned NumFields, 5794 SourceLocation LBrac, SourceLocation RBrac, 5795 AttributeList *Attr) { 5796 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5797 assert(EnclosingDecl && "missing record or interface decl"); 5798 5799 // If the decl this is being inserted into is invalid, then it may be a 5800 // redeclaration or some other bogus case. Don't try to add fields to it. 5801 if (EnclosingDecl->isInvalidDecl()) { 5802 // FIXME: Deallocate fields? 5803 return; 5804 } 5805 5806 5807 // Verify that all the fields are okay. 5808 unsigned NumNamedMembers = 0; 5809 llvm::SmallVector<FieldDecl*, 32> RecFields; 5810 5811 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5812 for (unsigned i = 0; i != NumFields; ++i) { 5813 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5814 5815 // Get the type for the field. 5816 Type *FDTy = FD->getType().getTypePtr(); 5817 5818 if (!FD->isAnonymousStructOrUnion()) { 5819 // Remember all fields written by the user. 5820 RecFields.push_back(FD); 5821 } 5822 5823 // If the field is already invalid for some reason, don't emit more 5824 // diagnostics about it. 5825 if (FD->isInvalidDecl()) { 5826 EnclosingDecl->setInvalidDecl(); 5827 continue; 5828 } 5829 5830 // C99 6.7.2.1p2: 5831 // A structure or union shall not contain a member with 5832 // incomplete or function type (hence, a structure shall not 5833 // contain an instance of itself, but may contain a pointer to 5834 // an instance of itself), except that the last member of a 5835 // structure with more than one named member may have incomplete 5836 // array type; such a structure (and any union containing, 5837 // possibly recursively, a member that is such a structure) 5838 // shall not be a member of a structure or an element of an 5839 // array. 5840 if (FDTy->isFunctionType()) { 5841 // Field declared as a function. 5842 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5843 << FD->getDeclName(); 5844 FD->setInvalidDecl(); 5845 EnclosingDecl->setInvalidDecl(); 5846 continue; 5847 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5848 Record && Record->isStruct()) { 5849 // Flexible array member. 5850 if (NumNamedMembers < 1) { 5851 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5852 << FD->getDeclName(); 5853 FD->setInvalidDecl(); 5854 EnclosingDecl->setInvalidDecl(); 5855 continue; 5856 } 5857 // Okay, we have a legal flexible array member at the end of the struct. 5858 if (Record) 5859 Record->setHasFlexibleArrayMember(true); 5860 } else if (!FDTy->isDependentType() && 5861 RequireCompleteType(FD->getLocation(), FD->getType(), 5862 diag::err_field_incomplete)) { 5863 // Incomplete type 5864 FD->setInvalidDecl(); 5865 EnclosingDecl->setInvalidDecl(); 5866 continue; 5867 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5868 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5869 // If this is a member of a union, then entire union becomes "flexible". 5870 if (Record && Record->isUnion()) { 5871 Record->setHasFlexibleArrayMember(true); 5872 } else { 5873 // If this is a struct/class and this is not the last element, reject 5874 // it. Note that GCC supports variable sized arrays in the middle of 5875 // structures. 5876 if (i != NumFields-1) 5877 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5878 << FD->getDeclName() << FD->getType(); 5879 else { 5880 // We support flexible arrays at the end of structs in 5881 // other structs as an extension. 5882 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5883 << FD->getDeclName(); 5884 if (Record) 5885 Record->setHasFlexibleArrayMember(true); 5886 } 5887 } 5888 } 5889 if (Record && FDTTy->getDecl()->hasObjectMember()) 5890 Record->setHasObjectMember(true); 5891 } else if (FDTy->isObjCInterfaceType()) { 5892 /// A field cannot be an Objective-c object 5893 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5894 FD->setInvalidDecl(); 5895 EnclosingDecl->setInvalidDecl(); 5896 continue; 5897 } else if (getLangOptions().ObjC1 && 5898 getLangOptions().getGCMode() != LangOptions::NonGC && 5899 Record && 5900 (FD->getType()->isObjCObjectPointerType() || 5901 FD->getType().isObjCGCStrong())) 5902 Record->setHasObjectMember(true); 5903 // Keep track of the number of named members. 5904 if (FD->getIdentifier()) 5905 ++NumNamedMembers; 5906 } 5907 5908 // Okay, we successfully defined 'Record'. 5909 if (Record) { 5910 Record->completeDefinition(); 5911 } else { 5912 ObjCIvarDecl **ClsFields = 5913 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5914 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5915 ID->setLocEnd(RBrac); 5916 // Add ivar's to class's DeclContext. 5917 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5918 ClsFields[i]->setLexicalDeclContext(ID); 5919 ID->addDecl(ClsFields[i]); 5920 } 5921 // Must enforce the rule that ivars in the base classes may not be 5922 // duplicates. 5923 if (ID->getSuperClass()) 5924 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 5925 } else if (ObjCImplementationDecl *IMPDecl = 5926 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5927 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5928 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5929 // Ivar declared in @implementation never belongs to the implementation. 5930 // Only it is in implementation's lexical context. 5931 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5932 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5933 } else if (ObjCCategoryDecl *CDecl = 5934 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5935 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) 5936 Diag(LBrac, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 5937 else { 5938 // FIXME. Class extension does not have a LocEnd field. 5939 // CDecl->setLocEnd(RBrac); 5940 // Add ivar's to class extension's DeclContext. 5941 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5942 ClsFields[i]->setLexicalDeclContext(CDecl); 5943 CDecl->addDecl(ClsFields[i]); 5944 } 5945 } 5946 } 5947 } 5948 5949 if (Attr) 5950 ProcessDeclAttributeList(S, Record, Attr); 5951} 5952 5953/// \brief Determine whether the given integral value is representable within 5954/// the given type T. 5955static bool isRepresentableIntegerValue(ASTContext &Context, 5956 llvm::APSInt &Value, 5957 QualType T) { 5958 assert(T->isIntegralType() && "Integral type required!"); 5959 unsigned BitWidth = Context.getTypeSize(T); 5960 5961 if (Value.isUnsigned() || Value.isNonNegative()) 5962 return Value.getActiveBits() < BitWidth; 5963 5964 return Value.getMinSignedBits() <= BitWidth; 5965} 5966 5967// \brief Given an integral type, return the next larger integral type 5968// (or a NULL type of no such type exists). 5969static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 5970 // FIXME: Int128/UInt128 support, which also needs to be introduced into 5971 // enum checking below. 5972 assert(T->isIntegralType() && "Integral type required!"); 5973 const unsigned NumTypes = 4; 5974 QualType SignedIntegralTypes[NumTypes] = { 5975 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 5976 }; 5977 QualType UnsignedIntegralTypes[NumTypes] = { 5978 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 5979 Context.UnsignedLongLongTy 5980 }; 5981 5982 unsigned BitWidth = Context.getTypeSize(T); 5983 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 5984 : UnsignedIntegralTypes; 5985 for (unsigned I = 0; I != NumTypes; ++I) 5986 if (Context.getTypeSize(Types[I]) > BitWidth) 5987 return Types[I]; 5988 5989 return QualType(); 5990} 5991 5992EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5993 EnumConstantDecl *LastEnumConst, 5994 SourceLocation IdLoc, 5995 IdentifierInfo *Id, 5996 ExprArg val) { 5997 Expr *Val = (Expr *)val.get(); 5998 5999 unsigned IntWidth = Context.Target.getIntWidth(); 6000 llvm::APSInt EnumVal(IntWidth); 6001 QualType EltTy; 6002 if (Val) { 6003 if (Enum->isDependentType() || Val->isTypeDependent()) 6004 EltTy = Context.DependentTy; 6005 else { 6006 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6007 SourceLocation ExpLoc; 6008 if (!Val->isValueDependent() && 6009 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6010 Val = 0; 6011 } else { 6012 if (!getLangOptions().CPlusPlus) { 6013 // C99 6.7.2.2p2: 6014 // The expression that defines the value of an enumeration constant 6015 // shall be an integer constant expression that has a value 6016 // representable as an int. 6017 6018 // Complain if the value is not representable in an int. 6019 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6020 Diag(IdLoc, diag::ext_enum_value_not_int) 6021 << EnumVal.toString(10) << Val->getSourceRange() 6022 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6023 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6024 // Force the type of the expression to 'int'. 6025 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6026 6027 if (Val != val.get()) { 6028 val.release(); 6029 val = Val; 6030 } 6031 } 6032 } 6033 6034 // C++0x [dcl.enum]p5: 6035 // If the underlying type is not fixed, the type of each enumerator 6036 // is the type of its initializing value: 6037 // - If an initializer is specified for an enumerator, the 6038 // initializing value has the same type as the expression. 6039 EltTy = Val->getType(); 6040 } 6041 } 6042 } 6043 6044 if (!Val) { 6045 if (Enum->isDependentType()) 6046 EltTy = Context.DependentTy; 6047 else if (!LastEnumConst) { 6048 // C++0x [dcl.enum]p5: 6049 // If the underlying type is not fixed, the type of each enumerator 6050 // is the type of its initializing value: 6051 // - If no initializer is specified for the first enumerator, the 6052 // initializing value has an unspecified integral type. 6053 // 6054 // GCC uses 'int' for its unspecified integral type, as does 6055 // C99 6.7.2.2p3. 6056 EltTy = Context.IntTy; 6057 } else { 6058 // Assign the last value + 1. 6059 EnumVal = LastEnumConst->getInitVal(); 6060 ++EnumVal; 6061 EltTy = LastEnumConst->getType(); 6062 6063 // Check for overflow on increment. 6064 if (EnumVal < LastEnumConst->getInitVal()) { 6065 // C++0x [dcl.enum]p5: 6066 // If the underlying type is not fixed, the type of each enumerator 6067 // is the type of its initializing value: 6068 // 6069 // - Otherwise the type of the initializing value is the same as 6070 // the type of the initializing value of the preceding enumerator 6071 // unless the incremented value is not representable in that type, 6072 // in which case the type is an unspecified integral type 6073 // sufficient to contain the incremented value. If no such type 6074 // exists, the program is ill-formed. 6075 QualType T = getNextLargerIntegralType(Context, EltTy); 6076 if (T.isNull()) { 6077 // There is no integral type larger enough to represent this 6078 // value. Complain, then allow the value to wrap around. 6079 EnumVal = LastEnumConst->getInitVal(); 6080 EnumVal.zext(EnumVal.getBitWidth() * 2); 6081 Diag(IdLoc, diag::warn_enumerator_too_large) 6082 << EnumVal.toString(10); 6083 } else { 6084 EltTy = T; 6085 } 6086 6087 // Retrieve the last enumerator's value, extent that type to the 6088 // type that is supposed to be large enough to represent the incremented 6089 // value, then increment. 6090 EnumVal = LastEnumConst->getInitVal(); 6091 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6092 EnumVal.zextOrTrunc(Context.getTypeSize(EltTy)); 6093 ++EnumVal; 6094 6095 // If we're not in C++, diagnose the overflow of enumerator values, 6096 // which in C99 means that the enumerator value is not representable in 6097 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6098 // permits enumerator values that are representable in some larger 6099 // integral type. 6100 if (!getLangOptions().CPlusPlus && !T.isNull()) 6101 Diag(IdLoc, diag::warn_enum_value_overflow); 6102 } else if (!getLangOptions().CPlusPlus && 6103 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6104 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6105 Diag(IdLoc, diag::ext_enum_value_not_int) 6106 << EnumVal.toString(10) << 1; 6107 } 6108 } 6109 } 6110 6111 if (!EltTy->isDependentType()) { 6112 // Make the enumerator value match the signedness and size of the 6113 // enumerator's type. 6114 EnumVal.zextOrTrunc(Context.getTypeSize(EltTy)); 6115 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6116 } 6117 6118 val.release(); 6119 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6120 Val, EnumVal); 6121} 6122 6123 6124Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6125 DeclPtrTy lastEnumConst, 6126 SourceLocation IdLoc, 6127 IdentifierInfo *Id, 6128 SourceLocation EqualLoc, ExprTy *val) { 6129 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6130 EnumConstantDecl *LastEnumConst = 6131 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6132 Expr *Val = static_cast<Expr*>(val); 6133 6134 // The scope passed in may not be a decl scope. Zip up the scope tree until 6135 // we find one that is. 6136 S = getNonFieldDeclScope(S); 6137 6138 // Verify that there isn't already something declared with this name in this 6139 // scope. 6140 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName, 6141 ForRedeclaration); 6142 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6143 // Maybe we will complain about the shadowed template parameter. 6144 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6145 // Just pretend that we didn't see the previous declaration. 6146 PrevDecl = 0; 6147 } 6148 6149 if (PrevDecl) { 6150 // When in C++, we may get a TagDecl with the same name; in this case the 6151 // enum constant will 'hide' the tag. 6152 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6153 "Received TagDecl when not in C++!"); 6154 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6155 if (isa<EnumConstantDecl>(PrevDecl)) 6156 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6157 else 6158 Diag(IdLoc, diag::err_redefinition) << Id; 6159 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6160 if (Val) Val->Destroy(Context); 6161 return DeclPtrTy(); 6162 } 6163 } 6164 6165 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6166 IdLoc, Id, Owned(Val)); 6167 6168 // Register this decl in the current scope stack. 6169 if (New) { 6170 New->setAccess(TheEnumDecl->getAccess()); 6171 PushOnScopeChains(New, S); 6172 } 6173 6174 return DeclPtrTy::make(New); 6175} 6176 6177void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6178 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6179 DeclPtrTy *Elements, unsigned NumElements, 6180 Scope *S, AttributeList *Attr) { 6181 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6182 QualType EnumType = Context.getTypeDeclType(Enum); 6183 6184 if (Attr) 6185 ProcessDeclAttributeList(S, Enum, Attr); 6186 6187 if (Enum->isDependentType()) { 6188 for (unsigned i = 0; i != NumElements; ++i) { 6189 EnumConstantDecl *ECD = 6190 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6191 if (!ECD) continue; 6192 6193 ECD->setType(EnumType); 6194 } 6195 6196 Enum->completeDefinition(Context.DependentTy, Context.DependentTy); 6197 return; 6198 } 6199 6200 // TODO: If the result value doesn't fit in an int, it must be a long or long 6201 // long value. ISO C does not support this, but GCC does as an extension, 6202 // emit a warning. 6203 unsigned IntWidth = Context.Target.getIntWidth(); 6204 unsigned CharWidth = Context.Target.getCharWidth(); 6205 unsigned ShortWidth = Context.Target.getShortWidth(); 6206 6207 // Verify that all the values are okay, compute the size of the values, and 6208 // reverse the list. 6209 unsigned NumNegativeBits = 0; 6210 unsigned NumPositiveBits = 0; 6211 6212 // Keep track of whether all elements have type int. 6213 bool AllElementsInt = true; 6214 6215 for (unsigned i = 0; i != NumElements; ++i) { 6216 EnumConstantDecl *ECD = 6217 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6218 if (!ECD) continue; // Already issued a diagnostic. 6219 6220 const llvm::APSInt &InitVal = ECD->getInitVal(); 6221 6222 // Keep track of the size of positive and negative values. 6223 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6224 NumPositiveBits = std::max(NumPositiveBits, 6225 (unsigned)InitVal.getActiveBits()); 6226 else 6227 NumNegativeBits = std::max(NumNegativeBits, 6228 (unsigned)InitVal.getMinSignedBits()); 6229 6230 // Keep track of whether every enum element has type int (very commmon). 6231 if (AllElementsInt) 6232 AllElementsInt = ECD->getType() == Context.IntTy; 6233 } 6234 6235 // Figure out the type that should be used for this enum. 6236 // FIXME: Support -fshort-enums. 6237 QualType BestType; 6238 unsigned BestWidth; 6239 6240 // C++0x N3000 [conv.prom]p3: 6241 // An rvalue of an unscoped enumeration type whose underlying 6242 // type is not fixed can be converted to an rvalue of the first 6243 // of the following types that can represent all the values of 6244 // the enumeration: int, unsigned int, long int, unsigned long 6245 // int, long long int, or unsigned long long int. 6246 // C99 6.4.4.3p2: 6247 // An identifier declared as an enumeration constant has type int. 6248 // The C99 rule is modified by a gcc extension 6249 QualType BestPromotionType; 6250 6251 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6252 6253 if (NumNegativeBits) { 6254 // If there is a negative value, figure out the smallest integer type (of 6255 // int/long/longlong) that fits. 6256 // If it's packed, check also if it fits a char or a short. 6257 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6258 BestType = Context.SignedCharTy; 6259 BestWidth = CharWidth; 6260 } else if (Packed && NumNegativeBits <= ShortWidth && 6261 NumPositiveBits < ShortWidth) { 6262 BestType = Context.ShortTy; 6263 BestWidth = ShortWidth; 6264 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6265 BestType = Context.IntTy; 6266 BestWidth = IntWidth; 6267 } else { 6268 BestWidth = Context.Target.getLongWidth(); 6269 6270 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6271 BestType = Context.LongTy; 6272 } else { 6273 BestWidth = Context.Target.getLongLongWidth(); 6274 6275 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6276 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6277 BestType = Context.LongLongTy; 6278 } 6279 } 6280 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6281 } else { 6282 // If there is no negative value, figure out the smallest type that fits 6283 // all of the enumerator values. 6284 // If it's packed, check also if it fits a char or a short. 6285 if (Packed && NumPositiveBits <= CharWidth) { 6286 BestType = Context.UnsignedCharTy; 6287 BestPromotionType = Context.IntTy; 6288 BestWidth = CharWidth; 6289 } else if (Packed && NumPositiveBits <= ShortWidth) { 6290 BestType = Context.UnsignedShortTy; 6291 BestPromotionType = Context.IntTy; 6292 BestWidth = ShortWidth; 6293 } else if (NumPositiveBits <= IntWidth) { 6294 BestType = Context.UnsignedIntTy; 6295 BestWidth = IntWidth; 6296 BestPromotionType 6297 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6298 ? Context.UnsignedIntTy : Context.IntTy; 6299 } else if (NumPositiveBits <= 6300 (BestWidth = Context.Target.getLongWidth())) { 6301 BestType = Context.UnsignedLongTy; 6302 BestPromotionType 6303 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6304 ? Context.UnsignedLongTy : Context.LongTy; 6305 } else { 6306 BestWidth = Context.Target.getLongLongWidth(); 6307 assert(NumPositiveBits <= BestWidth && 6308 "How could an initializer get larger than ULL?"); 6309 BestType = Context.UnsignedLongLongTy; 6310 BestPromotionType 6311 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6312 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6313 } 6314 } 6315 6316 // Loop over all of the enumerator constants, changing their types to match 6317 // the type of the enum if needed. 6318 for (unsigned i = 0; i != NumElements; ++i) { 6319 EnumConstantDecl *ECD = 6320 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6321 if (!ECD) continue; // Already issued a diagnostic. 6322 6323 // Standard C says the enumerators have int type, but we allow, as an 6324 // extension, the enumerators to be larger than int size. If each 6325 // enumerator value fits in an int, type it as an int, otherwise type it the 6326 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6327 // that X has type 'int', not 'unsigned'. 6328 6329 // Determine whether the value fits into an int. 6330 llvm::APSInt InitVal = ECD->getInitVal(); 6331 6332 // If it fits into an integer type, force it. Otherwise force it to match 6333 // the enum decl type. 6334 QualType NewTy; 6335 unsigned NewWidth; 6336 bool NewSign; 6337 if (!getLangOptions().CPlusPlus && 6338 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6339 NewTy = Context.IntTy; 6340 NewWidth = IntWidth; 6341 NewSign = true; 6342 } else if (ECD->getType() == BestType) { 6343 // Already the right type! 6344 if (getLangOptions().CPlusPlus) 6345 // C++ [dcl.enum]p4: Following the closing brace of an 6346 // enum-specifier, each enumerator has the type of its 6347 // enumeration. 6348 ECD->setType(EnumType); 6349 continue; 6350 } else { 6351 NewTy = BestType; 6352 NewWidth = BestWidth; 6353 NewSign = BestType->isSignedIntegerType(); 6354 } 6355 6356 // Adjust the APSInt value. 6357 InitVal.extOrTrunc(NewWidth); 6358 InitVal.setIsSigned(NewSign); 6359 ECD->setInitVal(InitVal); 6360 6361 // Adjust the Expr initializer and type. 6362 if (ECD->getInitExpr()) 6363 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6364 CastExpr::CK_IntegralCast, 6365 ECD->getInitExpr(), 6366 /*isLvalue=*/false)); 6367 if (getLangOptions().CPlusPlus) 6368 // C++ [dcl.enum]p4: Following the closing brace of an 6369 // enum-specifier, each enumerator has the type of its 6370 // enumeration. 6371 ECD->setType(EnumType); 6372 else 6373 ECD->setType(NewTy); 6374 } 6375 6376 Enum->completeDefinition(BestType, BestPromotionType); 6377} 6378 6379Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6380 ExprArg expr) { 6381 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6382 6383 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6384 Loc, AsmString); 6385 CurContext->addDecl(New); 6386 return DeclPtrTy::make(New); 6387} 6388 6389void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6390 SourceLocation PragmaLoc, 6391 SourceLocation NameLoc) { 6392 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6393 6394 if (PrevDecl) { 6395 PrevDecl->addAttr(::new (Context) WeakAttr()); 6396 } else { 6397 (void)WeakUndeclaredIdentifiers.insert( 6398 std::pair<IdentifierInfo*,WeakInfo> 6399 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6400 } 6401} 6402 6403void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6404 IdentifierInfo* AliasName, 6405 SourceLocation PragmaLoc, 6406 SourceLocation NameLoc, 6407 SourceLocation AliasNameLoc) { 6408 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6409 WeakInfo W = WeakInfo(Name, NameLoc); 6410 6411 if (PrevDecl) { 6412 if (!PrevDecl->hasAttr<AliasAttr>()) 6413 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6414 DeclApplyPragmaWeak(TUScope, ND, W); 6415 } else { 6416 (void)WeakUndeclaredIdentifiers.insert( 6417 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6418 } 6419} 6420