SemaDecl.cpp revision 8ff7d69e3cfae245a243edcf074dadd4883ae3a2
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/Analysis/PathSensitive/AnalysisContext.h" 18#include "clang/AST/APValue.h" 19#include "clang/AST/ASTConsumer.h" 20#include "clang/AST/ASTContext.h" 21#include "clang/Analysis/CFG.h" 22#include "clang/AST/CXXInheritance.h" 23#include "clang/AST/DeclObjC.h" 24#include "clang/AST/DeclTemplate.h" 25#include "clang/AST/ExprCXX.h" 26#include "clang/AST/StmtCXX.h" 27#include "clang/AST/StmtObjC.h" 28#include "clang/Parse/DeclSpec.h" 29#include "clang/Parse/ParseDiagnostic.h" 30#include "clang/Parse/Template.h" 31#include "clang/Basic/PartialDiagnostic.h" 32#include "clang/Basic/SourceManager.h" 33#include "clang/Basic/TargetInfo.h" 34// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 35#include "clang/Lex/Preprocessor.h" 36#include "clang/Lex/HeaderSearch.h" 37#include "llvm/ADT/BitVector.h" 38#include "llvm/ADT/STLExtras.h" 39#include "llvm/ADT/Triple.h" 40#include <algorithm> 41#include <cstring> 42#include <functional> 43#include <queue> 44using namespace clang; 45 46/// getDeclName - Return a pretty name for the specified decl if possible, or 47/// an empty string if not. This is used for pretty crash reporting. 48std::string Sema::getDeclName(DeclPtrTy d) { 49 Decl *D = d.getAs<Decl>(); 50 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 51 return DN->getQualifiedNameAsString(); 52 return ""; 53} 54 55Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 56 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 57} 58 59/// \brief If the identifier refers to a type name within this scope, 60/// return the declaration of that type. 61/// 62/// This routine performs ordinary name lookup of the identifier II 63/// within the given scope, with optional C++ scope specifier SS, to 64/// determine whether the name refers to a type. If so, returns an 65/// opaque pointer (actually a QualType) corresponding to that 66/// type. Otherwise, returns NULL. 67/// 68/// If name lookup results in an ambiguity, this routine will complain 69/// and then return NULL. 70Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 71 Scope *S, const CXXScopeSpec *SS, 72 bool isClassName, 73 TypeTy *ObjectTypePtr) { 74 // Determine where we will perform name lookup. 75 DeclContext *LookupCtx = 0; 76 if (ObjectTypePtr) { 77 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 78 if (ObjectType->isRecordType()) 79 LookupCtx = computeDeclContext(ObjectType); 80 } else if (SS && SS->isSet()) { 81 LookupCtx = computeDeclContext(*SS, false); 82 83 if (!LookupCtx) { 84 if (isDependentScopeSpecifier(*SS)) { 85 // C++ [temp.res]p3: 86 // A qualified-id that refers to a type and in which the 87 // nested-name-specifier depends on a template-parameter (14.6.2) 88 // shall be prefixed by the keyword typename to indicate that the 89 // qualified-id denotes a type, forming an 90 // elaborated-type-specifier (7.1.5.3). 91 // 92 // We therefore do not perform any name lookup if the result would 93 // refer to a member of an unknown specialization. 94 if (!isClassName) 95 return 0; 96 97 // We know from the grammar that this name refers to a type, so build a 98 // TypenameType node to describe the type. 99 // FIXME: Record somewhere that this TypenameType node has no "typename" 100 // keyword associated with it. 101 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 102 II, SS->getRange()).getAsOpaquePtr(); 103 } 104 105 return 0; 106 } 107 108 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 109 return 0; 110 } 111 112 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 113 // lookup for class-names. 114 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 115 LookupOrdinaryName; 116 LookupResult Result(*this, &II, NameLoc, Kind); 117 if (LookupCtx) { 118 // Perform "qualified" name lookup into the declaration context we 119 // computed, which is either the type of the base of a member access 120 // expression or the declaration context associated with a prior 121 // nested-name-specifier. 122 LookupQualifiedName(Result, LookupCtx); 123 124 if (ObjectTypePtr && Result.empty()) { 125 // C++ [basic.lookup.classref]p3: 126 // If the unqualified-id is ~type-name, the type-name is looked up 127 // in the context of the entire postfix-expression. If the type T of 128 // the object expression is of a class type C, the type-name is also 129 // looked up in the scope of class C. At least one of the lookups shall 130 // find a name that refers to (possibly cv-qualified) T. 131 LookupName(Result, S); 132 } 133 } else { 134 // Perform unqualified name lookup. 135 LookupName(Result, S); 136 } 137 138 NamedDecl *IIDecl = 0; 139 switch (Result.getResultKind()) { 140 case LookupResult::NotFound: 141 case LookupResult::NotFoundInCurrentInstantiation: 142 case LookupResult::FoundOverloaded: 143 case LookupResult::FoundUnresolvedValue: 144 return 0; 145 146 case LookupResult::Ambiguous: 147 // Recover from type-hiding ambiguities by hiding the type. We'll 148 // do the lookup again when looking for an object, and we can 149 // diagnose the error then. If we don't do this, then the error 150 // about hiding the type will be immediately followed by an error 151 // that only makes sense if the identifier was treated like a type. 152 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 153 Result.suppressDiagnostics(); 154 return 0; 155 } 156 157 // Look to see if we have a type anywhere in the list of results. 158 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 159 Res != ResEnd; ++Res) { 160 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 161 if (!IIDecl || 162 (*Res)->getLocation().getRawEncoding() < 163 IIDecl->getLocation().getRawEncoding()) 164 IIDecl = *Res; 165 } 166 } 167 168 if (!IIDecl) { 169 // None of the entities we found is a type, so there is no way 170 // to even assume that the result is a type. In this case, don't 171 // complain about the ambiguity. The parser will either try to 172 // perform this lookup again (e.g., as an object name), which 173 // will produce the ambiguity, or will complain that it expected 174 // a type name. 175 Result.suppressDiagnostics(); 176 return 0; 177 } 178 179 // We found a type within the ambiguous lookup; diagnose the 180 // ambiguity and then return that type. This might be the right 181 // answer, or it might not be, but it suppresses any attempt to 182 // perform the name lookup again. 183 break; 184 185 case LookupResult::Found: 186 IIDecl = Result.getFoundDecl(); 187 break; 188 } 189 190 assert(IIDecl && "Didn't find decl"); 191 192 QualType T; 193 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 194 DiagnoseUseOfDecl(IIDecl, NameLoc); 195 196 // C++ [temp.local]p2: 197 // Within the scope of a class template specialization or 198 // partial specialization, when the injected-class-name is 199 // not followed by a <, it is equivalent to the 200 // injected-class-name followed by the template-argument s 201 // of the class template specialization or partial 202 // specialization enclosed in <>. 203 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 204 if (RD->isInjectedClassName()) 205 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 206 T = Template->getInjectedClassNameType(Context); 207 208 if (T.isNull()) 209 T = Context.getTypeDeclType(TD); 210 211 if (SS) 212 T = getQualifiedNameType(*SS, T); 213 214 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 215 T = Context.getObjCInterfaceType(IDecl); 216 } else if (UnresolvedUsingTypenameDecl *UUDecl = 217 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 218 // FIXME: preserve source structure information. 219 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 220 } else { 221 // If it's not plausibly a type, suppress diagnostics. 222 Result.suppressDiagnostics(); 223 return 0; 224 } 225 226 return T.getAsOpaquePtr(); 227} 228 229/// isTagName() - This method is called *for error recovery purposes only* 230/// to determine if the specified name is a valid tag name ("struct foo"). If 231/// so, this returns the TST for the tag corresponding to it (TST_enum, 232/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 233/// where the user forgot to specify the tag. 234DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 235 // Do a tag name lookup in this scope. 236 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 237 LookupName(R, S, false); 238 R.suppressDiagnostics(); 239 if (R.getResultKind() == LookupResult::Found) 240 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 241 switch (TD->getTagKind()) { 242 case TagDecl::TK_struct: return DeclSpec::TST_struct; 243 case TagDecl::TK_union: return DeclSpec::TST_union; 244 case TagDecl::TK_class: return DeclSpec::TST_class; 245 case TagDecl::TK_enum: return DeclSpec::TST_enum; 246 } 247 } 248 249 return DeclSpec::TST_unspecified; 250} 251 252bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 253 SourceLocation IILoc, 254 Scope *S, 255 const CXXScopeSpec *SS, 256 TypeTy *&SuggestedType) { 257 // We don't have anything to suggest (yet). 258 SuggestedType = 0; 259 260 // There may have been a typo in the name of the type. Look up typo 261 // results, in case we have something that we can suggest. 262 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 263 NotForRedeclaration); 264 265 // FIXME: It would be nice if we could correct for typos in built-in 266 // names, such as "itn" for "int". 267 268 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 269 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 270 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 271 !Result->isInvalidDecl()) { 272 // We found a similarly-named type or interface; suggest that. 273 if (!SS || !SS->isSet()) 274 Diag(IILoc, diag::err_unknown_typename_suggest) 275 << &II << Lookup.getLookupName() 276 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 277 Result->getNameAsString()); 278 else if (DeclContext *DC = computeDeclContext(*SS, false)) 279 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 280 << &II << DC << Lookup.getLookupName() << SS->getRange() 281 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 282 Result->getNameAsString()); 283 else 284 llvm_unreachable("could not have corrected a typo here"); 285 286 Diag(Result->getLocation(), diag::note_previous_decl) 287 << Result->getDeclName(); 288 289 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 290 return true; 291 } 292 } 293 294 // FIXME: Should we move the logic that tries to recover from a missing tag 295 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 296 297 if (!SS || (!SS->isSet() && !SS->isInvalid())) 298 Diag(IILoc, diag::err_unknown_typename) << &II; 299 else if (DeclContext *DC = computeDeclContext(*SS, false)) 300 Diag(IILoc, diag::err_typename_nested_not_found) 301 << &II << DC << SS->getRange(); 302 else if (isDependentScopeSpecifier(*SS)) { 303 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 304 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 305 << SourceRange(SS->getRange().getBegin(), IILoc) 306 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 307 "typename "); 308 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 309 } else { 310 assert(SS && SS->isInvalid() && 311 "Invalid scope specifier has already been diagnosed"); 312 } 313 314 return true; 315} 316 317// Determines the context to return to after temporarily entering a 318// context. This depends in an unnecessarily complicated way on the 319// exact ordering of callbacks from the parser. 320DeclContext *Sema::getContainingDC(DeclContext *DC) { 321 322 // Functions defined inline within classes aren't parsed until we've 323 // finished parsing the top-level class, so the top-level class is 324 // the context we'll need to return to. 325 if (isa<FunctionDecl>(DC)) { 326 DC = DC->getLexicalParent(); 327 328 // A function not defined within a class will always return to its 329 // lexical context. 330 if (!isa<CXXRecordDecl>(DC)) 331 return DC; 332 333 // A C++ inline method/friend is parsed *after* the topmost class 334 // it was declared in is fully parsed ("complete"); the topmost 335 // class is the context we need to return to. 336 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 337 DC = RD; 338 339 // Return the declaration context of the topmost class the inline method is 340 // declared in. 341 return DC; 342 } 343 344 if (isa<ObjCMethodDecl>(DC)) 345 return Context.getTranslationUnitDecl(); 346 347 return DC->getLexicalParent(); 348} 349 350void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 351 assert(getContainingDC(DC) == CurContext && 352 "The next DeclContext should be lexically contained in the current one."); 353 CurContext = DC; 354 S->setEntity(DC); 355} 356 357void Sema::PopDeclContext() { 358 assert(CurContext && "DeclContext imbalance!"); 359 360 CurContext = getContainingDC(CurContext); 361} 362 363/// EnterDeclaratorContext - Used when we must lookup names in the context 364/// of a declarator's nested name specifier. 365/// 366void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 367 // C++0x [basic.lookup.unqual]p13: 368 // A name used in the definition of a static data member of class 369 // X (after the qualified-id of the static member) is looked up as 370 // if the name was used in a member function of X. 371 // C++0x [basic.lookup.unqual]p14: 372 // If a variable member of a namespace is defined outside of the 373 // scope of its namespace then any name used in the definition of 374 // the variable member (after the declarator-id) is looked up as 375 // if the definition of the variable member occurred in its 376 // namespace. 377 // Both of these imply that we should push a scope whose context 378 // is the semantic context of the declaration. We can't use 379 // PushDeclContext here because that context is not necessarily 380 // lexically contained in the current context. Fortunately, 381 // the containing scope should have the appropriate information. 382 383 assert(!S->getEntity() && "scope already has entity"); 384 385#ifndef NDEBUG 386 Scope *Ancestor = S->getParent(); 387 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 388 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 389#endif 390 391 CurContext = DC; 392 S->setEntity(DC); 393} 394 395void Sema::ExitDeclaratorContext(Scope *S) { 396 assert(S->getEntity() == CurContext && "Context imbalance!"); 397 398 // Switch back to the lexical context. The safety of this is 399 // enforced by an assert in EnterDeclaratorContext. 400 Scope *Ancestor = S->getParent(); 401 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 402 CurContext = (DeclContext*) Ancestor->getEntity(); 403 404 // We don't need to do anything with the scope, which is going to 405 // disappear. 406} 407 408/// \brief Determine whether we allow overloading of the function 409/// PrevDecl with another declaration. 410/// 411/// This routine determines whether overloading is possible, not 412/// whether some new function is actually an overload. It will return 413/// true in C++ (where we can always provide overloads) or, as an 414/// extension, in C when the previous function is already an 415/// overloaded function declaration or has the "overloadable" 416/// attribute. 417static bool AllowOverloadingOfFunction(LookupResult &Previous, 418 ASTContext &Context) { 419 if (Context.getLangOptions().CPlusPlus) 420 return true; 421 422 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 423 return true; 424 425 return (Previous.getResultKind() == LookupResult::Found 426 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 427} 428 429/// Add this decl to the scope shadowed decl chains. 430void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 431 // Move up the scope chain until we find the nearest enclosing 432 // non-transparent context. The declaration will be introduced into this 433 // scope. 434 while (S->getEntity() && 435 ((DeclContext *)S->getEntity())->isTransparentContext()) 436 S = S->getParent(); 437 438 // Add scoped declarations into their context, so that they can be 439 // found later. Declarations without a context won't be inserted 440 // into any context. 441 if (AddToContext) 442 CurContext->addDecl(D); 443 444 // Out-of-line function and variable definitions should not be pushed into 445 // scope. 446 if ((isa<FunctionTemplateDecl>(D) && 447 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 448 (isa<FunctionDecl>(D) && 449 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 450 cast<FunctionDecl>(D)->isOutOfLine())) || 451 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 452 return; 453 454 // If this replaces anything in the current scope, 455 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 456 IEnd = IdResolver.end(); 457 for (; I != IEnd; ++I) { 458 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 459 S->RemoveDecl(DeclPtrTy::make(*I)); 460 IdResolver.RemoveDecl(*I); 461 462 // Should only need to replace one decl. 463 break; 464 } 465 } 466 467 S->AddDecl(DeclPtrTy::make(D)); 468 IdResolver.AddDecl(D); 469} 470 471bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 472 return IdResolver.isDeclInScope(D, Ctx, Context, S); 473} 474 475static bool isOutOfScopePreviousDeclaration(NamedDecl *, 476 DeclContext*, 477 ASTContext&); 478 479/// Filters out lookup results that don't fall within the given scope 480/// as determined by isDeclInScope. 481static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 482 DeclContext *Ctx, Scope *S, 483 bool ConsiderLinkage) { 484 LookupResult::Filter F = R.makeFilter(); 485 while (F.hasNext()) { 486 NamedDecl *D = F.next(); 487 488 if (SemaRef.isDeclInScope(D, Ctx, S)) 489 continue; 490 491 if (ConsiderLinkage && 492 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 493 continue; 494 495 F.erase(); 496 } 497 498 F.done(); 499} 500 501static bool isUsingDecl(NamedDecl *D) { 502 return isa<UsingShadowDecl>(D) || 503 isa<UnresolvedUsingTypenameDecl>(D) || 504 isa<UnresolvedUsingValueDecl>(D); 505} 506 507/// Removes using shadow declarations from the lookup results. 508static void RemoveUsingDecls(LookupResult &R) { 509 LookupResult::Filter F = R.makeFilter(); 510 while (F.hasNext()) 511 if (isUsingDecl(F.next())) 512 F.erase(); 513 514 F.done(); 515} 516 517static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 518 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 519 return false; 520 521 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 522 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 523 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 524 if (!RD->hasTrivialConstructor()) 525 return false; 526 if (!RD->hasTrivialDestructor()) 527 return false; 528 } 529 } 530 } 531 532 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 533 !isa<ImplicitParamDecl>(D) && 534 D->getDeclContext()->isFunctionOrMethod()); 535} 536 537void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 538 if (S->decl_empty()) return; 539 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 540 "Scope shouldn't contain decls!"); 541 542 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 543 I != E; ++I) { 544 Decl *TmpD = (*I).getAs<Decl>(); 545 assert(TmpD && "This decl didn't get pushed??"); 546 547 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 548 NamedDecl *D = cast<NamedDecl>(TmpD); 549 550 if (!D->getDeclName()) continue; 551 552 // Diagnose unused variables in this scope. 553 if (ShouldDiagnoseUnusedDecl(D)) 554 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 555 556 // Remove this name from our lexical scope. 557 IdResolver.RemoveDecl(D); 558 } 559} 560 561/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 562/// return 0 if one not found. 563/// 564/// \param Id the name of the Objective-C class we're looking for. If 565/// typo-correction fixes this name, the Id will be updated 566/// to the fixed name. 567/// 568/// \param RecoverLoc if provided, this routine will attempt to 569/// recover from a typo in the name of an existing Objective-C class 570/// and, if successful, will return the lookup that results from 571/// typo-correction. 572ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 573 SourceLocation RecoverLoc) { 574 // The third "scope" argument is 0 since we aren't enabling lazy built-in 575 // creation from this context. 576 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 577 578 if (!IDecl && !RecoverLoc.isInvalid()) { 579 // Perform typo correction at the given location, but only if we 580 // find an Objective-C class name. 581 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 582 if (CorrectTypo(R, TUScope, 0) && 583 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 584 Diag(RecoverLoc, diag::err_undef_interface_suggest) 585 << Id << IDecl->getDeclName() 586 << CodeModificationHint::CreateReplacement(RecoverLoc, 587 IDecl->getNameAsString()); 588 Diag(IDecl->getLocation(), diag::note_previous_decl) 589 << IDecl->getDeclName(); 590 591 Id = IDecl->getIdentifier(); 592 } 593 } 594 595 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 596} 597 598/// getNonFieldDeclScope - Retrieves the innermost scope, starting 599/// from S, where a non-field would be declared. This routine copes 600/// with the difference between C and C++ scoping rules in structs and 601/// unions. For example, the following code is well-formed in C but 602/// ill-formed in C++: 603/// @code 604/// struct S6 { 605/// enum { BAR } e; 606/// }; 607/// 608/// void test_S6() { 609/// struct S6 a; 610/// a.e = BAR; 611/// } 612/// @endcode 613/// For the declaration of BAR, this routine will return a different 614/// scope. The scope S will be the scope of the unnamed enumeration 615/// within S6. In C++, this routine will return the scope associated 616/// with S6, because the enumeration's scope is a transparent 617/// context but structures can contain non-field names. In C, this 618/// routine will return the translation unit scope, since the 619/// enumeration's scope is a transparent context and structures cannot 620/// contain non-field names. 621Scope *Sema::getNonFieldDeclScope(Scope *S) { 622 while (((S->getFlags() & Scope::DeclScope) == 0) || 623 (S->getEntity() && 624 ((DeclContext *)S->getEntity())->isTransparentContext()) || 625 (S->isClassScope() && !getLangOptions().CPlusPlus)) 626 S = S->getParent(); 627 return S; 628} 629 630void Sema::InitBuiltinVaListType() { 631 if (!Context.getBuiltinVaListType().isNull()) 632 return; 633 634 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 635 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 636 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 637 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 638} 639 640/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 641/// file scope. lazily create a decl for it. ForRedeclaration is true 642/// if we're creating this built-in in anticipation of redeclaring the 643/// built-in. 644NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 645 Scope *S, bool ForRedeclaration, 646 SourceLocation Loc) { 647 Builtin::ID BID = (Builtin::ID)bid; 648 649 if (Context.BuiltinInfo.hasVAListUse(BID)) 650 InitBuiltinVaListType(); 651 652 ASTContext::GetBuiltinTypeError Error; 653 QualType R = Context.GetBuiltinType(BID, Error); 654 switch (Error) { 655 case ASTContext::GE_None: 656 // Okay 657 break; 658 659 case ASTContext::GE_Missing_stdio: 660 if (ForRedeclaration) 661 Diag(Loc, diag::err_implicit_decl_requires_stdio) 662 << Context.BuiltinInfo.GetName(BID); 663 return 0; 664 665 case ASTContext::GE_Missing_setjmp: 666 if (ForRedeclaration) 667 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 668 << Context.BuiltinInfo.GetName(BID); 669 return 0; 670 } 671 672 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 673 Diag(Loc, diag::ext_implicit_lib_function_decl) 674 << Context.BuiltinInfo.GetName(BID) 675 << R; 676 if (Context.BuiltinInfo.getHeaderName(BID) && 677 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 678 != Diagnostic::Ignored) 679 Diag(Loc, diag::note_please_include_header) 680 << Context.BuiltinInfo.getHeaderName(BID) 681 << Context.BuiltinInfo.GetName(BID); 682 } 683 684 FunctionDecl *New = FunctionDecl::Create(Context, 685 Context.getTranslationUnitDecl(), 686 Loc, II, R, /*TInfo=*/0, 687 FunctionDecl::Extern, false, 688 /*hasPrototype=*/true); 689 New->setImplicit(); 690 691 // Create Decl objects for each parameter, adding them to the 692 // FunctionDecl. 693 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 694 llvm::SmallVector<ParmVarDecl*, 16> Params; 695 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 696 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 697 FT->getArgType(i), /*TInfo=*/0, 698 VarDecl::None, 0)); 699 New->setParams(Context, Params.data(), Params.size()); 700 } 701 702 AddKnownFunctionAttributes(New); 703 704 // TUScope is the translation-unit scope to insert this function into. 705 // FIXME: This is hideous. We need to teach PushOnScopeChains to 706 // relate Scopes to DeclContexts, and probably eliminate CurContext 707 // entirely, but we're not there yet. 708 DeclContext *SavedContext = CurContext; 709 CurContext = Context.getTranslationUnitDecl(); 710 PushOnScopeChains(New, TUScope); 711 CurContext = SavedContext; 712 return New; 713} 714 715/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 716/// same name and scope as a previous declaration 'Old'. Figure out 717/// how to resolve this situation, merging decls or emitting 718/// diagnostics as appropriate. If there was an error, set New to be invalid. 719/// 720void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 721 // If the new decl is known invalid already, don't bother doing any 722 // merging checks. 723 if (New->isInvalidDecl()) return; 724 725 // Allow multiple definitions for ObjC built-in typedefs. 726 // FIXME: Verify the underlying types are equivalent! 727 if (getLangOptions().ObjC1) { 728 const IdentifierInfo *TypeID = New->getIdentifier(); 729 switch (TypeID->getLength()) { 730 default: break; 731 case 2: 732 if (!TypeID->isStr("id")) 733 break; 734 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 735 // Install the built-in type for 'id', ignoring the current definition. 736 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 737 return; 738 case 5: 739 if (!TypeID->isStr("Class")) 740 break; 741 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 742 // Install the built-in type for 'Class', ignoring the current definition. 743 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 744 return; 745 case 3: 746 if (!TypeID->isStr("SEL")) 747 break; 748 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 749 // Install the built-in type for 'SEL', ignoring the current definition. 750 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 751 return; 752 case 8: 753 if (!TypeID->isStr("Protocol")) 754 break; 755 Context.setObjCProtoType(New->getUnderlyingType()); 756 return; 757 } 758 // Fall through - the typedef name was not a builtin type. 759 } 760 761 // Verify the old decl was also a type. 762 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 763 if (!Old) { 764 Diag(New->getLocation(), diag::err_redefinition_different_kind) 765 << New->getDeclName(); 766 767 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 768 if (OldD->getLocation().isValid()) 769 Diag(OldD->getLocation(), diag::note_previous_definition); 770 771 return New->setInvalidDecl(); 772 } 773 774 // If the old declaration is invalid, just give up here. 775 if (Old->isInvalidDecl()) 776 return New->setInvalidDecl(); 777 778 // Determine the "old" type we'll use for checking and diagnostics. 779 QualType OldType; 780 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 781 OldType = OldTypedef->getUnderlyingType(); 782 else 783 OldType = Context.getTypeDeclType(Old); 784 785 // If the typedef types are not identical, reject them in all languages and 786 // with any extensions enabled. 787 788 if (OldType != New->getUnderlyingType() && 789 Context.getCanonicalType(OldType) != 790 Context.getCanonicalType(New->getUnderlyingType())) { 791 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 792 << New->getUnderlyingType() << OldType; 793 if (Old->getLocation().isValid()) 794 Diag(Old->getLocation(), diag::note_previous_definition); 795 return New->setInvalidDecl(); 796 } 797 798 // The types match. Link up the redeclaration chain if the old 799 // declaration was a typedef. 800 // FIXME: this is a potential source of wierdness if the type 801 // spellings don't match exactly. 802 if (isa<TypedefDecl>(Old)) 803 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 804 805 if (getLangOptions().Microsoft) 806 return; 807 808 if (getLangOptions().CPlusPlus) { 809 // C++ [dcl.typedef]p2: 810 // In a given non-class scope, a typedef specifier can be used to 811 // redefine the name of any type declared in that scope to refer 812 // to the type to which it already refers. 813 if (!isa<CXXRecordDecl>(CurContext)) 814 return; 815 816 // C++0x [dcl.typedef]p4: 817 // In a given class scope, a typedef specifier can be used to redefine 818 // any class-name declared in that scope that is not also a typedef-name 819 // to refer to the type to which it already refers. 820 // 821 // This wording came in via DR424, which was a correction to the 822 // wording in DR56, which accidentally banned code like: 823 // 824 // struct S { 825 // typedef struct A { } A; 826 // }; 827 // 828 // in the C++03 standard. We implement the C++0x semantics, which 829 // allow the above but disallow 830 // 831 // struct S { 832 // typedef int I; 833 // typedef int I; 834 // }; 835 // 836 // since that was the intent of DR56. 837 if (!isa<TypedefDecl >(Old)) 838 return; 839 840 Diag(New->getLocation(), diag::err_redefinition) 841 << New->getDeclName(); 842 Diag(Old->getLocation(), diag::note_previous_definition); 843 return New->setInvalidDecl(); 844 } 845 846 // If we have a redefinition of a typedef in C, emit a warning. This warning 847 // is normally mapped to an error, but can be controlled with 848 // -Wtypedef-redefinition. If either the original or the redefinition is 849 // in a system header, don't emit this for compatibility with GCC. 850 if (PP.getDiagnostics().getSuppressSystemWarnings() && 851 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 852 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 853 return; 854 855 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 856 << New->getDeclName(); 857 Diag(Old->getLocation(), diag::note_previous_definition); 858 return; 859} 860 861/// DeclhasAttr - returns true if decl Declaration already has the target 862/// attribute. 863static bool 864DeclHasAttr(const Decl *decl, const Attr *target) { 865 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 866 if (attr->getKind() == target->getKind()) 867 return true; 868 869 return false; 870} 871 872/// MergeAttributes - append attributes from the Old decl to the New one. 873static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 874 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 875 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 876 Attr *NewAttr = attr->clone(C); 877 NewAttr->setInherited(true); 878 New->addAttr(NewAttr); 879 } 880 } 881} 882 883/// Used in MergeFunctionDecl to keep track of function parameters in 884/// C. 885struct GNUCompatibleParamWarning { 886 ParmVarDecl *OldParm; 887 ParmVarDecl *NewParm; 888 QualType PromotedType; 889}; 890 891 892/// getSpecialMember - get the special member enum for a method. 893static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 894 const CXXMethodDecl *MD) { 895 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 896 if (Ctor->isDefaultConstructor()) 897 return Sema::CXXDefaultConstructor; 898 if (Ctor->isCopyConstructor()) 899 return Sema::CXXCopyConstructor; 900 } 901 902 if (isa<CXXDestructorDecl>(MD)) 903 return Sema::CXXDestructor; 904 905 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 906 return Sema::CXXCopyAssignment; 907} 908 909/// MergeFunctionDecl - We just parsed a function 'New' from 910/// declarator D which has the same name and scope as a previous 911/// declaration 'Old'. Figure out how to resolve this situation, 912/// merging decls or emitting diagnostics as appropriate. 913/// 914/// In C++, New and Old must be declarations that are not 915/// overloaded. Use IsOverload to determine whether New and Old are 916/// overloaded, and to select the Old declaration that New should be 917/// merged with. 918/// 919/// Returns true if there was an error, false otherwise. 920bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 921 // Verify the old decl was also a function. 922 FunctionDecl *Old = 0; 923 if (FunctionTemplateDecl *OldFunctionTemplate 924 = dyn_cast<FunctionTemplateDecl>(OldD)) 925 Old = OldFunctionTemplate->getTemplatedDecl(); 926 else 927 Old = dyn_cast<FunctionDecl>(OldD); 928 if (!Old) { 929 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 930 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 931 Diag(Shadow->getTargetDecl()->getLocation(), 932 diag::note_using_decl_target); 933 Diag(Shadow->getUsingDecl()->getLocation(), 934 diag::note_using_decl) << 0; 935 return true; 936 } 937 938 Diag(New->getLocation(), diag::err_redefinition_different_kind) 939 << New->getDeclName(); 940 Diag(OldD->getLocation(), diag::note_previous_definition); 941 return true; 942 } 943 944 // Determine whether the previous declaration was a definition, 945 // implicit declaration, or a declaration. 946 diag::kind PrevDiag; 947 if (Old->isThisDeclarationADefinition()) 948 PrevDiag = diag::note_previous_definition; 949 else if (Old->isImplicit()) 950 PrevDiag = diag::note_previous_implicit_declaration; 951 else 952 PrevDiag = diag::note_previous_declaration; 953 954 QualType OldQType = Context.getCanonicalType(Old->getType()); 955 QualType NewQType = Context.getCanonicalType(New->getType()); 956 957 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 958 New->getStorageClass() == FunctionDecl::Static && 959 Old->getStorageClass() != FunctionDecl::Static) { 960 Diag(New->getLocation(), diag::err_static_non_static) 961 << New; 962 Diag(Old->getLocation(), PrevDiag); 963 return true; 964 } 965 966 if (getLangOptions().CPlusPlus) { 967 // (C++98 13.1p2): 968 // Certain function declarations cannot be overloaded: 969 // -- Function declarations that differ only in the return type 970 // cannot be overloaded. 971 QualType OldReturnType 972 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 973 QualType NewReturnType 974 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 975 if (OldReturnType != NewReturnType) { 976 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 977 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 978 return true; 979 } 980 981 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 982 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 983 if (OldMethod && NewMethod) { 984 if (!NewMethod->getFriendObjectKind() && 985 NewMethod->getLexicalDeclContext()->isRecord()) { 986 // -- Member function declarations with the same name and the 987 // same parameter types cannot be overloaded if any of them 988 // is a static member function declaration. 989 if (OldMethod->isStatic() || NewMethod->isStatic()) { 990 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 991 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 992 return true; 993 } 994 995 // C++ [class.mem]p1: 996 // [...] A member shall not be declared twice in the 997 // member-specification, except that a nested class or member 998 // class template can be declared and then later defined. 999 unsigned NewDiag; 1000 if (isa<CXXConstructorDecl>(OldMethod)) 1001 NewDiag = diag::err_constructor_redeclared; 1002 else if (isa<CXXDestructorDecl>(NewMethod)) 1003 NewDiag = diag::err_destructor_redeclared; 1004 else if (isa<CXXConversionDecl>(NewMethod)) 1005 NewDiag = diag::err_conv_function_redeclared; 1006 else 1007 NewDiag = diag::err_member_redeclared; 1008 1009 Diag(New->getLocation(), NewDiag); 1010 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1011 } else { 1012 if (OldMethod->isImplicit()) { 1013 Diag(NewMethod->getLocation(), 1014 diag::err_definition_of_implicitly_declared_member) 1015 << New << getSpecialMember(Context, OldMethod); 1016 1017 Diag(OldMethod->getLocation(), 1018 diag::note_previous_implicit_declaration); 1019 return true; 1020 } 1021 } 1022 } 1023 1024 // (C++98 8.3.5p3): 1025 // All declarations for a function shall agree exactly in both the 1026 // return type and the parameter-type-list. 1027 // attributes should be ignored when comparing. 1028 if (Context.getNoReturnType(OldQType, false) == 1029 Context.getNoReturnType(NewQType, false)) 1030 return MergeCompatibleFunctionDecls(New, Old); 1031 1032 // Fall through for conflicting redeclarations and redefinitions. 1033 } 1034 1035 // C: Function types need to be compatible, not identical. This handles 1036 // duplicate function decls like "void f(int); void f(enum X);" properly. 1037 if (!getLangOptions().CPlusPlus && 1038 Context.typesAreCompatible(OldQType, NewQType)) { 1039 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1040 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1041 const FunctionProtoType *OldProto = 0; 1042 if (isa<FunctionNoProtoType>(NewFuncType) && 1043 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1044 // The old declaration provided a function prototype, but the 1045 // new declaration does not. Merge in the prototype. 1046 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1047 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1048 OldProto->arg_type_end()); 1049 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1050 ParamTypes.data(), ParamTypes.size(), 1051 OldProto->isVariadic(), 1052 OldProto->getTypeQuals()); 1053 New->setType(NewQType); 1054 New->setHasInheritedPrototype(); 1055 1056 // Synthesize a parameter for each argument type. 1057 llvm::SmallVector<ParmVarDecl*, 16> Params; 1058 for (FunctionProtoType::arg_type_iterator 1059 ParamType = OldProto->arg_type_begin(), 1060 ParamEnd = OldProto->arg_type_end(); 1061 ParamType != ParamEnd; ++ParamType) { 1062 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1063 SourceLocation(), 0, 1064 *ParamType, /*TInfo=*/0, 1065 VarDecl::None, 0); 1066 Param->setImplicit(); 1067 Params.push_back(Param); 1068 } 1069 1070 New->setParams(Context, Params.data(), Params.size()); 1071 } 1072 1073 return MergeCompatibleFunctionDecls(New, Old); 1074 } 1075 1076 // GNU C permits a K&R definition to follow a prototype declaration 1077 // if the declared types of the parameters in the K&R definition 1078 // match the types in the prototype declaration, even when the 1079 // promoted types of the parameters from the K&R definition differ 1080 // from the types in the prototype. GCC then keeps the types from 1081 // the prototype. 1082 // 1083 // If a variadic prototype is followed by a non-variadic K&R definition, 1084 // the K&R definition becomes variadic. This is sort of an edge case, but 1085 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1086 // C99 6.9.1p8. 1087 if (!getLangOptions().CPlusPlus && 1088 Old->hasPrototype() && !New->hasPrototype() && 1089 New->getType()->getAs<FunctionProtoType>() && 1090 Old->getNumParams() == New->getNumParams()) { 1091 llvm::SmallVector<QualType, 16> ArgTypes; 1092 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1093 const FunctionProtoType *OldProto 1094 = Old->getType()->getAs<FunctionProtoType>(); 1095 const FunctionProtoType *NewProto 1096 = New->getType()->getAs<FunctionProtoType>(); 1097 1098 // Determine whether this is the GNU C extension. 1099 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1100 NewProto->getResultType()); 1101 bool LooseCompatible = !MergedReturn.isNull(); 1102 for (unsigned Idx = 0, End = Old->getNumParams(); 1103 LooseCompatible && Idx != End; ++Idx) { 1104 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1105 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1106 if (Context.typesAreCompatible(OldParm->getType(), 1107 NewProto->getArgType(Idx))) { 1108 ArgTypes.push_back(NewParm->getType()); 1109 } else if (Context.typesAreCompatible(OldParm->getType(), 1110 NewParm->getType())) { 1111 GNUCompatibleParamWarning Warn 1112 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1113 Warnings.push_back(Warn); 1114 ArgTypes.push_back(NewParm->getType()); 1115 } else 1116 LooseCompatible = false; 1117 } 1118 1119 if (LooseCompatible) { 1120 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1121 Diag(Warnings[Warn].NewParm->getLocation(), 1122 diag::ext_param_promoted_not_compatible_with_prototype) 1123 << Warnings[Warn].PromotedType 1124 << Warnings[Warn].OldParm->getType(); 1125 Diag(Warnings[Warn].OldParm->getLocation(), 1126 diag::note_previous_declaration); 1127 } 1128 1129 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1130 ArgTypes.size(), 1131 OldProto->isVariadic(), 0)); 1132 return MergeCompatibleFunctionDecls(New, Old); 1133 } 1134 1135 // Fall through to diagnose conflicting types. 1136 } 1137 1138 // A function that has already been declared has been redeclared or defined 1139 // with a different type- show appropriate diagnostic 1140 if (unsigned BuiltinID = Old->getBuiltinID()) { 1141 // The user has declared a builtin function with an incompatible 1142 // signature. 1143 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1144 // The function the user is redeclaring is a library-defined 1145 // function like 'malloc' or 'printf'. Warn about the 1146 // redeclaration, then pretend that we don't know about this 1147 // library built-in. 1148 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1149 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1150 << Old << Old->getType(); 1151 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1152 Old->setInvalidDecl(); 1153 return false; 1154 } 1155 1156 PrevDiag = diag::note_previous_builtin_declaration; 1157 } 1158 1159 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1160 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1161 return true; 1162} 1163 1164/// \brief Completes the merge of two function declarations that are 1165/// known to be compatible. 1166/// 1167/// This routine handles the merging of attributes and other 1168/// properties of function declarations form the old declaration to 1169/// the new declaration, once we know that New is in fact a 1170/// redeclaration of Old. 1171/// 1172/// \returns false 1173bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1174 // Merge the attributes 1175 MergeAttributes(New, Old, Context); 1176 1177 // Merge the storage class. 1178 if (Old->getStorageClass() != FunctionDecl::Extern && 1179 Old->getStorageClass() != FunctionDecl::None) 1180 New->setStorageClass(Old->getStorageClass()); 1181 1182 // Merge "pure" flag. 1183 if (Old->isPure()) 1184 New->setPure(); 1185 1186 // Merge the "deleted" flag. 1187 if (Old->isDeleted()) 1188 New->setDeleted(); 1189 1190 if (getLangOptions().CPlusPlus) 1191 return MergeCXXFunctionDecl(New, Old); 1192 1193 return false; 1194} 1195 1196/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1197/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1198/// situation, merging decls or emitting diagnostics as appropriate. 1199/// 1200/// Tentative definition rules (C99 6.9.2p2) are checked by 1201/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1202/// definitions here, since the initializer hasn't been attached. 1203/// 1204void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1205 // If the new decl is already invalid, don't do any other checking. 1206 if (New->isInvalidDecl()) 1207 return; 1208 1209 // Verify the old decl was also a variable. 1210 VarDecl *Old = 0; 1211 if (!Previous.isSingleResult() || 1212 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1213 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1214 << New->getDeclName(); 1215 Diag(Previous.getRepresentativeDecl()->getLocation(), 1216 diag::note_previous_definition); 1217 return New->setInvalidDecl(); 1218 } 1219 1220 MergeAttributes(New, Old, Context); 1221 1222 // Merge the types 1223 QualType MergedT; 1224 if (getLangOptions().CPlusPlus) { 1225 if (Context.hasSameType(New->getType(), Old->getType())) 1226 MergedT = New->getType(); 1227 // C++ [basic.link]p10: 1228 // [...] the types specified by all declarations referring to a given 1229 // object or function shall be identical, except that declarations for an 1230 // array object can specify array types that differ by the presence or 1231 // absence of a major array bound (8.3.4). 1232 else if (Old->getType()->isIncompleteArrayType() && 1233 New->getType()->isArrayType()) { 1234 CanQual<ArrayType> OldArray 1235 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1236 CanQual<ArrayType> NewArray 1237 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1238 if (OldArray->getElementType() == NewArray->getElementType()) 1239 MergedT = New->getType(); 1240 } else if (Old->getType()->isArrayType() && 1241 New->getType()->isIncompleteArrayType()) { 1242 CanQual<ArrayType> OldArray 1243 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1244 CanQual<ArrayType> NewArray 1245 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1246 if (OldArray->getElementType() == NewArray->getElementType()) 1247 MergedT = Old->getType(); 1248 } 1249 } else { 1250 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1251 } 1252 if (MergedT.isNull()) { 1253 Diag(New->getLocation(), diag::err_redefinition_different_type) 1254 << New->getDeclName(); 1255 Diag(Old->getLocation(), diag::note_previous_definition); 1256 return New->setInvalidDecl(); 1257 } 1258 New->setType(MergedT); 1259 1260 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1261 if (New->getStorageClass() == VarDecl::Static && 1262 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1263 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1264 Diag(Old->getLocation(), diag::note_previous_definition); 1265 return New->setInvalidDecl(); 1266 } 1267 // C99 6.2.2p4: 1268 // For an identifier declared with the storage-class specifier 1269 // extern in a scope in which a prior declaration of that 1270 // identifier is visible,23) if the prior declaration specifies 1271 // internal or external linkage, the linkage of the identifier at 1272 // the later declaration is the same as the linkage specified at 1273 // the prior declaration. If no prior declaration is visible, or 1274 // if the prior declaration specifies no linkage, then the 1275 // identifier has external linkage. 1276 if (New->hasExternalStorage() && Old->hasLinkage()) 1277 /* Okay */; 1278 else if (New->getStorageClass() != VarDecl::Static && 1279 Old->getStorageClass() == VarDecl::Static) { 1280 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1281 Diag(Old->getLocation(), diag::note_previous_definition); 1282 return New->setInvalidDecl(); 1283 } 1284 1285 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1286 1287 // FIXME: The test for external storage here seems wrong? We still 1288 // need to check for mismatches. 1289 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1290 // Don't complain about out-of-line definitions of static members. 1291 !(Old->getLexicalDeclContext()->isRecord() && 1292 !New->getLexicalDeclContext()->isRecord())) { 1293 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1294 Diag(Old->getLocation(), diag::note_previous_definition); 1295 return New->setInvalidDecl(); 1296 } 1297 1298 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1299 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1300 Diag(Old->getLocation(), diag::note_previous_definition); 1301 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1302 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1303 Diag(Old->getLocation(), diag::note_previous_definition); 1304 } 1305 1306 // Keep a chain of previous declarations. 1307 New->setPreviousDeclaration(Old); 1308} 1309 1310static void MarkLive(CFGBlock *e, llvm::BitVector &live) { 1311 std::queue<CFGBlock*> workq; 1312 // Prep work queue 1313 workq.push(e); 1314 // Solve 1315 while (!workq.empty()) { 1316 CFGBlock *item = workq.front(); 1317 workq.pop(); 1318 live.set(item->getBlockID()); 1319 for (CFGBlock::succ_iterator I=item->succ_begin(), 1320 E=item->succ_end(); 1321 I != E; 1322 ++I) { 1323 if ((*I) && !live[(*I)->getBlockID()]) { 1324 live.set((*I)->getBlockID()); 1325 workq.push(*I); 1326 } 1327 } 1328 } 1329} 1330 1331static SourceLocation GetUnreachableLoc(CFGBlock &b) { 1332 Stmt *S; 1333 if (!b.empty()) 1334 S = b[0].getStmt(); 1335 else if (b.getTerminator()) 1336 S = b.getTerminator(); 1337 else 1338 return SourceLocation(); 1339 1340 switch (S->getStmtClass()) { 1341 case Expr::BinaryOperatorClass: { 1342 if (b.size() < 2) { 1343 CFGBlock *n = &b; 1344 while (1) { 1345 if (n->getTerminator()) 1346 return n->getTerminator()->getLocStart(); 1347 if (n->succ_size() != 1) 1348 return SourceLocation(); 1349 n = n[0].succ_begin()[0]; 1350 if (n->pred_size() != 1) 1351 return SourceLocation(); 1352 if (!n->empty()) 1353 return n[0][0].getStmt()->getLocStart(); 1354 } 1355 } 1356 return b[1].getStmt()->getLocStart(); 1357 } 1358 default: ; 1359 } 1360 return S->getLocStart(); 1361} 1362 1363static SourceLocation MarkLiveTop(CFGBlock *e, llvm::BitVector &live, 1364 SourceManager &SM) { 1365 std::queue<CFGBlock*> workq; 1366 // Prep work queue 1367 workq.push(e); 1368 SourceLocation top = GetUnreachableLoc(*e); 1369 bool FromMainFile = false; 1370 bool FromSystemHeader = false; 1371 bool TopValid = false; 1372 if (top.isValid()) { 1373 FromMainFile = SM.isFromMainFile(top); 1374 FromSystemHeader = SM.isInSystemHeader(top); 1375 TopValid = true; 1376 } 1377 // Solve 1378 while (!workq.empty()) { 1379 CFGBlock *item = workq.front(); 1380 workq.pop(); 1381 SourceLocation c = GetUnreachableLoc(*item); 1382 if (c.isValid() 1383 && (!TopValid 1384 || (SM.isFromMainFile(c) && !FromMainFile) 1385 || (FromSystemHeader && !SM.isInSystemHeader(c)) 1386 || SM.isBeforeInTranslationUnit(c, top))) { 1387 top = c; 1388 FromMainFile = SM.isFromMainFile(top); 1389 FromSystemHeader = SM.isInSystemHeader(top); 1390 } 1391 live.set(item->getBlockID()); 1392 for (CFGBlock::succ_iterator I=item->succ_begin(), 1393 E=item->succ_end(); 1394 I != E; 1395 ++I) { 1396 if ((*I) && !live[(*I)->getBlockID()]) { 1397 live.set((*I)->getBlockID()); 1398 workq.push(*I); 1399 } 1400 } 1401 } 1402 return top; 1403} 1404 1405namespace { 1406class LineCmp { 1407 SourceManager &SM; 1408public: 1409 LineCmp(SourceManager &sm) : SM(sm) { 1410 } 1411 bool operator () (SourceLocation l1, SourceLocation l2) { 1412 return l1 < l2; 1413 } 1414}; 1415} 1416 1417/// CheckUnreachable - Check for unreachable code. 1418void Sema::CheckUnreachable(AnalysisContext &AC) { 1419 // We avoid checking when there are errors, as the CFG won't faithfully match 1420 // the user's code. 1421 if (getDiagnostics().hasErrorOccurred()) 1422 return; 1423 if (Diags.getDiagnosticLevel(diag::warn_unreachable) == Diagnostic::Ignored) 1424 return; 1425 1426 CFG *cfg = AC.getCFG(); 1427 if (cfg == 0) 1428 return; 1429 1430 llvm::BitVector live(cfg->getNumBlockIDs()); 1431 // Mark all live things first. 1432 MarkLive(&cfg->getEntry(), live); 1433 1434 llvm::SmallVector<SourceLocation, 24> lines; 1435 // First, give warnings for blocks with no predecessors, as they 1436 // can't be part of a loop. 1437 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1438 CFGBlock &b = **I; 1439 if (!live[b.getBlockID()]) { 1440 if (b.pred_begin() == b.pred_end()) { 1441 SourceLocation c = GetUnreachableLoc(b); 1442 if (!c.isValid()) { 1443 // Blocks without a location can't produce a warning, so don't mark 1444 // reachable blocks from here as live. 1445 live.set(b.getBlockID()); 1446 continue; 1447 } 1448 lines.push_back(c); 1449 // Avoid excessive errors by marking everything reachable from here 1450 MarkLive(&b, live); 1451 } 1452 } 1453 } 1454 1455 // And then give warnings for the tops of loops. 1456 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1457 CFGBlock &b = **I; 1458 if (!live[b.getBlockID()]) 1459 // Avoid excessive errors by marking everything reachable from here 1460 lines.push_back(MarkLiveTop(&b, live, Context.getSourceManager())); 1461 } 1462 1463 std::sort(lines.begin(), lines.end(), LineCmp(Context.getSourceManager())); 1464 for (llvm::SmallVector<SourceLocation, 24>::iterator I = lines.begin(), 1465 E = lines.end(); 1466 I != E; 1467 ++I) 1468 if (I->isValid()) 1469 Diag(*I, diag::warn_unreachable); 1470} 1471 1472/// CheckFallThrough - Check that we don't fall off the end of a 1473/// Statement that should return a value. 1474/// 1475/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1476/// MaybeFallThrough iff we might or might not fall off the end, 1477/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1478/// return. We assume NeverFallThrough iff we never fall off the end of the 1479/// statement but we may return. We assume that functions not marked noreturn 1480/// will return. 1481Sema::ControlFlowKind Sema::CheckFallThrough(AnalysisContext &AC) { 1482 CFG *cfg = AC.getCFG(); 1483 if (cfg == 0) 1484 // FIXME: This should be NeverFallThrough 1485 return NeverFallThroughOrReturn; 1486 1487 // The CFG leaves in dead things, and we don't want to dead code paths to 1488 // confuse us, so we mark all live things first. 1489 std::queue<CFGBlock*> workq; 1490 llvm::BitVector live(cfg->getNumBlockIDs()); 1491 MarkLive(&cfg->getEntry(), live); 1492 1493 // Now we know what is live, we check the live precessors of the exit block 1494 // and look for fall through paths, being careful to ignore normal returns, 1495 // and exceptional paths. 1496 bool HasLiveReturn = false; 1497 bool HasFakeEdge = false; 1498 bool HasPlainEdge = false; 1499 bool HasAbnormalEdge = false; 1500 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1501 E = cfg->getExit().pred_end(); 1502 I != E; 1503 ++I) { 1504 CFGBlock& B = **I; 1505 if (!live[B.getBlockID()]) 1506 continue; 1507 if (B.size() == 0) { 1508 // A labeled empty statement, or the entry block... 1509 HasPlainEdge = true; 1510 continue; 1511 } 1512 Stmt *S = B[B.size()-1]; 1513 if (isa<ReturnStmt>(S)) { 1514 HasLiveReturn = true; 1515 continue; 1516 } 1517 if (isa<ObjCAtThrowStmt>(S)) { 1518 HasFakeEdge = true; 1519 continue; 1520 } 1521 if (isa<CXXThrowExpr>(S)) { 1522 HasFakeEdge = true; 1523 continue; 1524 } 1525 if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) { 1526 if (AS->isMSAsm()) { 1527 HasFakeEdge = true; 1528 HasLiveReturn = true; 1529 continue; 1530 } 1531 } 1532 if (isa<CXXTryStmt>(S)) { 1533 HasAbnormalEdge = true; 1534 continue; 1535 } 1536 1537 bool NoReturnEdge = false; 1538 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1539 if (B.succ_begin()[0] != &cfg->getExit()) { 1540 HasAbnormalEdge = true; 1541 continue; 1542 } 1543 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1544 if (CEE->getType().getNoReturnAttr()) { 1545 NoReturnEdge = true; 1546 HasFakeEdge = true; 1547 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1548 ValueDecl *VD = DRE->getDecl(); 1549 if (VD->hasAttr<NoReturnAttr>()) { 1550 NoReturnEdge = true; 1551 HasFakeEdge = true; 1552 } 1553 } 1554 } 1555 // FIXME: Add noreturn message sends. 1556 if (NoReturnEdge == false) 1557 HasPlainEdge = true; 1558 } 1559 if (!HasPlainEdge) { 1560 if (HasLiveReturn) 1561 return NeverFallThrough; 1562 return NeverFallThroughOrReturn; 1563 } 1564 if (HasAbnormalEdge || HasFakeEdge || HasLiveReturn) 1565 return MaybeFallThrough; 1566 // This says AlwaysFallThrough for calls to functions that are not marked 1567 // noreturn, that don't return. If people would like this warning to be more 1568 // accurate, such functions should be marked as noreturn. 1569 return AlwaysFallThrough; 1570} 1571 1572/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1573/// function that should return a value. Check that we don't fall off the end 1574/// of a noreturn function. We assume that functions and blocks not marked 1575/// noreturn will return. 1576void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body, 1577 AnalysisContext &AC) { 1578 // FIXME: Would be nice if we had a better way to control cascading errors, 1579 // but for now, avoid them. The problem is that when Parse sees: 1580 // int foo() { return a; } 1581 // The return is eaten and the Sema code sees just: 1582 // int foo() { } 1583 // which this code would then warn about. 1584 if (getDiagnostics().hasErrorOccurred()) 1585 return; 1586 1587 bool ReturnsVoid = false; 1588 bool HasNoReturn = false; 1589 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1590 // If the result type of the function is a dependent type, we don't know 1591 // whether it will be void or not, so don't 1592 if (FD->getResultType()->isDependentType()) 1593 return; 1594 if (FD->getResultType()->isVoidType()) 1595 ReturnsVoid = true; 1596 if (FD->hasAttr<NoReturnAttr>()) 1597 HasNoReturn = true; 1598 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1599 if (MD->getResultType()->isVoidType()) 1600 ReturnsVoid = true; 1601 if (MD->hasAttr<NoReturnAttr>()) 1602 HasNoReturn = true; 1603 } 1604 1605 // Short circuit for compilation speed. 1606 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1607 == Diagnostic::Ignored || ReturnsVoid) 1608 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1609 == Diagnostic::Ignored || !HasNoReturn) 1610 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1611 == Diagnostic::Ignored || !ReturnsVoid)) 1612 return; 1613 // FIXME: Function try block 1614 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1615 switch (CheckFallThrough(AC)) { 1616 case MaybeFallThrough: 1617 if (HasNoReturn) 1618 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1619 else if (!ReturnsVoid) 1620 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1621 break; 1622 case AlwaysFallThrough: 1623 if (HasNoReturn) 1624 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1625 else if (!ReturnsVoid) 1626 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1627 break; 1628 case NeverFallThroughOrReturn: 1629 if (ReturnsVoid && !HasNoReturn) 1630 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1631 break; 1632 case NeverFallThrough: 1633 break; 1634 } 1635 } 1636} 1637 1638/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1639/// that should return a value. Check that we don't fall off the end of a 1640/// noreturn block. We assume that functions and blocks not marked noreturn 1641/// will return. 1642void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body, 1643 AnalysisContext &AC) { 1644 // FIXME: Would be nice if we had a better way to control cascading errors, 1645 // but for now, avoid them. The problem is that when Parse sees: 1646 // int foo() { return a; } 1647 // The return is eaten and the Sema code sees just: 1648 // int foo() { } 1649 // which this code would then warn about. 1650 if (getDiagnostics().hasErrorOccurred()) 1651 return; 1652 bool ReturnsVoid = false; 1653 bool HasNoReturn = false; 1654 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1655 if (FT->getResultType()->isVoidType()) 1656 ReturnsVoid = true; 1657 if (FT->getNoReturnAttr()) 1658 HasNoReturn = true; 1659 } 1660 1661 // Short circuit for compilation speed. 1662 if (ReturnsVoid 1663 && !HasNoReturn 1664 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1665 == Diagnostic::Ignored || !ReturnsVoid)) 1666 return; 1667 // FIXME: Funtion try block 1668 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1669 switch (CheckFallThrough(AC)) { 1670 case MaybeFallThrough: 1671 if (HasNoReturn) 1672 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1673 else if (!ReturnsVoid) 1674 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1675 break; 1676 case AlwaysFallThrough: 1677 if (HasNoReturn) 1678 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1679 else if (!ReturnsVoid) 1680 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1681 break; 1682 case NeverFallThroughOrReturn: 1683 if (ReturnsVoid) 1684 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1685 break; 1686 case NeverFallThrough: 1687 break; 1688 } 1689 } 1690} 1691 1692/// CheckParmsForFunctionDef - Check that the parameters of the given 1693/// function are appropriate for the definition of a function. This 1694/// takes care of any checks that cannot be performed on the 1695/// declaration itself, e.g., that the types of each of the function 1696/// parameters are complete. 1697bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1698 bool HasInvalidParm = false; 1699 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1700 ParmVarDecl *Param = FD->getParamDecl(p); 1701 1702 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1703 // function declarator that is part of a function definition of 1704 // that function shall not have incomplete type. 1705 // 1706 // This is also C++ [dcl.fct]p6. 1707 if (!Param->isInvalidDecl() && 1708 RequireCompleteType(Param->getLocation(), Param->getType(), 1709 diag::err_typecheck_decl_incomplete_type)) { 1710 Param->setInvalidDecl(); 1711 HasInvalidParm = true; 1712 } 1713 1714 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1715 // declaration of each parameter shall include an identifier. 1716 if (Param->getIdentifier() == 0 && 1717 !Param->isImplicit() && 1718 !getLangOptions().CPlusPlus) 1719 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1720 } 1721 1722 return HasInvalidParm; 1723} 1724 1725/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1726/// no declarator (e.g. "struct foo;") is parsed. 1727Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1728 // FIXME: Error on auto/register at file scope 1729 // FIXME: Error on inline/virtual/explicit 1730 // FIXME: Warn on useless __thread 1731 // FIXME: Warn on useless const/volatile 1732 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1733 // FIXME: Warn on useless attributes 1734 Decl *TagD = 0; 1735 TagDecl *Tag = 0; 1736 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1737 DS.getTypeSpecType() == DeclSpec::TST_struct || 1738 DS.getTypeSpecType() == DeclSpec::TST_union || 1739 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1740 TagD = static_cast<Decl *>(DS.getTypeRep()); 1741 1742 if (!TagD) // We probably had an error 1743 return DeclPtrTy(); 1744 1745 // Note that the above type specs guarantee that the 1746 // type rep is a Decl, whereas in many of the others 1747 // it's a Type. 1748 Tag = dyn_cast<TagDecl>(TagD); 1749 } 1750 1751 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1752 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1753 // or incomplete types shall not be restrict-qualified." 1754 if (TypeQuals & DeclSpec::TQ_restrict) 1755 Diag(DS.getRestrictSpecLoc(), 1756 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1757 << DS.getSourceRange(); 1758 } 1759 1760 if (DS.isFriendSpecified()) { 1761 // If we're dealing with a class template decl, assume that the 1762 // template routines are handling it. 1763 if (TagD && isa<ClassTemplateDecl>(TagD)) 1764 return DeclPtrTy(); 1765 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1766 } 1767 1768 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1769 // If there are attributes in the DeclSpec, apply them to the record. 1770 if (const AttributeList *AL = DS.getAttributes()) 1771 ProcessDeclAttributeList(S, Record, AL); 1772 1773 if (!Record->getDeclName() && Record->isDefinition() && 1774 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1775 if (getLangOptions().CPlusPlus || 1776 Record->getDeclContext()->isRecord()) 1777 return BuildAnonymousStructOrUnion(S, DS, Record); 1778 1779 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1780 << DS.getSourceRange(); 1781 } 1782 1783 // Microsoft allows unnamed struct/union fields. Don't complain 1784 // about them. 1785 // FIXME: Should we support Microsoft's extensions in this area? 1786 if (Record->getDeclName() && getLangOptions().Microsoft) 1787 return DeclPtrTy::make(Tag); 1788 } 1789 1790 if (!DS.isMissingDeclaratorOk() && 1791 DS.getTypeSpecType() != DeclSpec::TST_error) { 1792 // Warn about typedefs of enums without names, since this is an 1793 // extension in both Microsoft an GNU. 1794 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1795 Tag && isa<EnumDecl>(Tag)) { 1796 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1797 << DS.getSourceRange(); 1798 return DeclPtrTy::make(Tag); 1799 } 1800 1801 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1802 << DS.getSourceRange(); 1803 return DeclPtrTy(); 1804 } 1805 1806 return DeclPtrTy::make(Tag); 1807} 1808 1809/// We are trying to inject an anonymous member into the given scope; 1810/// check if there's an existing declaration that can't be overloaded. 1811/// 1812/// \return true if this is a forbidden redeclaration 1813static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1814 Scope *S, 1815 DeclarationName Name, 1816 SourceLocation NameLoc, 1817 unsigned diagnostic) { 1818 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1819 Sema::ForRedeclaration); 1820 if (!SemaRef.LookupName(R, S)) return false; 1821 1822 if (R.getAsSingle<TagDecl>()) 1823 return false; 1824 1825 // Pick a representative declaration. 1826 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1827 1828 SemaRef.Diag(NameLoc, diagnostic) << Name; 1829 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1830 1831 return true; 1832} 1833 1834/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1835/// anonymous struct or union AnonRecord into the owning context Owner 1836/// and scope S. This routine will be invoked just after we realize 1837/// that an unnamed union or struct is actually an anonymous union or 1838/// struct, e.g., 1839/// 1840/// @code 1841/// union { 1842/// int i; 1843/// float f; 1844/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1845/// // f into the surrounding scope.x 1846/// @endcode 1847/// 1848/// This routine is recursive, injecting the names of nested anonymous 1849/// structs/unions into the owning context and scope as well. 1850bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1851 RecordDecl *AnonRecord) { 1852 unsigned diagKind 1853 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1854 : diag::err_anonymous_struct_member_redecl; 1855 1856 bool Invalid = false; 1857 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1858 FEnd = AnonRecord->field_end(); 1859 F != FEnd; ++F) { 1860 if ((*F)->getDeclName()) { 1861 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1862 (*F)->getLocation(), diagKind)) { 1863 // C++ [class.union]p2: 1864 // The names of the members of an anonymous union shall be 1865 // distinct from the names of any other entity in the 1866 // scope in which the anonymous union is declared. 1867 Invalid = true; 1868 } else { 1869 // C++ [class.union]p2: 1870 // For the purpose of name lookup, after the anonymous union 1871 // definition, the members of the anonymous union are 1872 // considered to have been defined in the scope in which the 1873 // anonymous union is declared. 1874 Owner->makeDeclVisibleInContext(*F); 1875 S->AddDecl(DeclPtrTy::make(*F)); 1876 IdResolver.AddDecl(*F); 1877 } 1878 } else if (const RecordType *InnerRecordType 1879 = (*F)->getType()->getAs<RecordType>()) { 1880 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1881 if (InnerRecord->isAnonymousStructOrUnion()) 1882 Invalid = Invalid || 1883 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1884 } 1885 } 1886 1887 return Invalid; 1888} 1889 1890/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1891/// anonymous structure or union. Anonymous unions are a C++ feature 1892/// (C++ [class.union]) and a GNU C extension; anonymous structures 1893/// are a GNU C and GNU C++ extension. 1894Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1895 RecordDecl *Record) { 1896 DeclContext *Owner = Record->getDeclContext(); 1897 1898 // Diagnose whether this anonymous struct/union is an extension. 1899 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1900 Diag(Record->getLocation(), diag::ext_anonymous_union); 1901 else if (!Record->isUnion()) 1902 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1903 1904 // C and C++ require different kinds of checks for anonymous 1905 // structs/unions. 1906 bool Invalid = false; 1907 if (getLangOptions().CPlusPlus) { 1908 const char* PrevSpec = 0; 1909 unsigned DiagID; 1910 // C++ [class.union]p3: 1911 // Anonymous unions declared in a named namespace or in the 1912 // global namespace shall be declared static. 1913 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1914 (isa<TranslationUnitDecl>(Owner) || 1915 (isa<NamespaceDecl>(Owner) && 1916 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1917 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1918 Invalid = true; 1919 1920 // Recover by adding 'static'. 1921 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1922 PrevSpec, DiagID); 1923 } 1924 // C++ [class.union]p3: 1925 // A storage class is not allowed in a declaration of an 1926 // anonymous union in a class scope. 1927 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1928 isa<RecordDecl>(Owner)) { 1929 Diag(DS.getStorageClassSpecLoc(), 1930 diag::err_anonymous_union_with_storage_spec); 1931 Invalid = true; 1932 1933 // Recover by removing the storage specifier. 1934 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1935 PrevSpec, DiagID); 1936 } 1937 1938 // C++ [class.union]p2: 1939 // The member-specification of an anonymous union shall only 1940 // define non-static data members. [Note: nested types and 1941 // functions cannot be declared within an anonymous union. ] 1942 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1943 MemEnd = Record->decls_end(); 1944 Mem != MemEnd; ++Mem) { 1945 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1946 // C++ [class.union]p3: 1947 // An anonymous union shall not have private or protected 1948 // members (clause 11). 1949 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1950 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1951 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1952 Invalid = true; 1953 } 1954 } else if ((*Mem)->isImplicit()) { 1955 // Any implicit members are fine. 1956 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1957 // This is a type that showed up in an 1958 // elaborated-type-specifier inside the anonymous struct or 1959 // union, but which actually declares a type outside of the 1960 // anonymous struct or union. It's okay. 1961 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1962 if (!MemRecord->isAnonymousStructOrUnion() && 1963 MemRecord->getDeclName()) { 1964 // This is a nested type declaration. 1965 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1966 << (int)Record->isUnion(); 1967 Invalid = true; 1968 } 1969 } else { 1970 // We have something that isn't a non-static data 1971 // member. Complain about it. 1972 unsigned DK = diag::err_anonymous_record_bad_member; 1973 if (isa<TypeDecl>(*Mem)) 1974 DK = diag::err_anonymous_record_with_type; 1975 else if (isa<FunctionDecl>(*Mem)) 1976 DK = diag::err_anonymous_record_with_function; 1977 else if (isa<VarDecl>(*Mem)) 1978 DK = diag::err_anonymous_record_with_static; 1979 Diag((*Mem)->getLocation(), DK) 1980 << (int)Record->isUnion(); 1981 Invalid = true; 1982 } 1983 } 1984 } 1985 1986 if (!Record->isUnion() && !Owner->isRecord()) { 1987 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1988 << (int)getLangOptions().CPlusPlus; 1989 Invalid = true; 1990 } 1991 1992 // Mock up a declarator. 1993 Declarator Dc(DS, Declarator::TypeNameContext); 1994 TypeSourceInfo *TInfo = 0; 1995 GetTypeForDeclarator(Dc, S, &TInfo); 1996 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1997 1998 // Create a declaration for this anonymous struct/union. 1999 NamedDecl *Anon = 0; 2000 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2001 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 2002 /*IdentifierInfo=*/0, 2003 Context.getTypeDeclType(Record), 2004 TInfo, 2005 /*BitWidth=*/0, /*Mutable=*/false); 2006 Anon->setAccess(AS_public); 2007 if (getLangOptions().CPlusPlus) 2008 FieldCollector->Add(cast<FieldDecl>(Anon)); 2009 } else { 2010 VarDecl::StorageClass SC; 2011 switch (DS.getStorageClassSpec()) { 2012 default: assert(0 && "Unknown storage class!"); 2013 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2014 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2015 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2016 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2017 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2018 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2019 case DeclSpec::SCS_mutable: 2020 // mutable can only appear on non-static class members, so it's always 2021 // an error here 2022 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2023 Invalid = true; 2024 SC = VarDecl::None; 2025 break; 2026 } 2027 2028 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 2029 /*IdentifierInfo=*/0, 2030 Context.getTypeDeclType(Record), 2031 TInfo, 2032 SC); 2033 } 2034 Anon->setImplicit(); 2035 2036 // Add the anonymous struct/union object to the current 2037 // context. We'll be referencing this object when we refer to one of 2038 // its members. 2039 Owner->addDecl(Anon); 2040 2041 // Inject the members of the anonymous struct/union into the owning 2042 // context and into the identifier resolver chain for name lookup 2043 // purposes. 2044 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 2045 Invalid = true; 2046 2047 // Mark this as an anonymous struct/union type. Note that we do not 2048 // do this until after we have already checked and injected the 2049 // members of this anonymous struct/union type, because otherwise 2050 // the members could be injected twice: once by DeclContext when it 2051 // builds its lookup table, and once by 2052 // InjectAnonymousStructOrUnionMembers. 2053 Record->setAnonymousStructOrUnion(true); 2054 2055 if (Invalid) 2056 Anon->setInvalidDecl(); 2057 2058 return DeclPtrTy::make(Anon); 2059} 2060 2061 2062/// GetNameForDeclarator - Determine the full declaration name for the 2063/// given Declarator. 2064DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 2065 return GetNameFromUnqualifiedId(D.getName()); 2066} 2067 2068/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 2069DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2070 switch (Name.getKind()) { 2071 case UnqualifiedId::IK_Identifier: 2072 return DeclarationName(Name.Identifier); 2073 2074 case UnqualifiedId::IK_OperatorFunctionId: 2075 return Context.DeclarationNames.getCXXOperatorName( 2076 Name.OperatorFunctionId.Operator); 2077 2078 case UnqualifiedId::IK_LiteralOperatorId: 2079 return Context.DeclarationNames.getCXXLiteralOperatorName( 2080 Name.Identifier); 2081 2082 case UnqualifiedId::IK_ConversionFunctionId: { 2083 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 2084 if (Ty.isNull()) 2085 return DeclarationName(); 2086 2087 return Context.DeclarationNames.getCXXConversionFunctionName( 2088 Context.getCanonicalType(Ty)); 2089 } 2090 2091 case UnqualifiedId::IK_ConstructorName: { 2092 QualType Ty = GetTypeFromParser(Name.ConstructorName); 2093 if (Ty.isNull()) 2094 return DeclarationName(); 2095 2096 return Context.DeclarationNames.getCXXConstructorName( 2097 Context.getCanonicalType(Ty)); 2098 } 2099 2100 case UnqualifiedId::IK_ConstructorTemplateId: { 2101 // In well-formed code, we can only have a constructor 2102 // template-id that refers to the current context, so go there 2103 // to find the actual type being constructed. 2104 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2105 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2106 return DeclarationName(); 2107 2108 // Determine the type of the class being constructed. 2109 QualType CurClassType; 2110 if (ClassTemplateDecl *ClassTemplate 2111 = CurClass->getDescribedClassTemplate()) 2112 CurClassType = ClassTemplate->getInjectedClassNameType(Context); 2113 else 2114 CurClassType = Context.getTypeDeclType(CurClass); 2115 2116 // FIXME: Check two things: that the template-id names the same type as 2117 // CurClassType, and that the template-id does not occur when the name 2118 // was qualified. 2119 2120 return Context.DeclarationNames.getCXXConstructorName( 2121 Context.getCanonicalType(CurClassType)); 2122 } 2123 2124 case UnqualifiedId::IK_DestructorName: { 2125 QualType Ty = GetTypeFromParser(Name.DestructorName); 2126 if (Ty.isNull()) 2127 return DeclarationName(); 2128 2129 return Context.DeclarationNames.getCXXDestructorName( 2130 Context.getCanonicalType(Ty)); 2131 } 2132 2133 case UnqualifiedId::IK_TemplateId: { 2134 TemplateName TName 2135 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2136 return Context.getNameForTemplate(TName); 2137 } 2138 } 2139 2140 assert(false && "Unknown name kind"); 2141 return DeclarationName(); 2142} 2143 2144/// isNearlyMatchingFunction - Determine whether the C++ functions 2145/// Declaration and Definition are "nearly" matching. This heuristic 2146/// is used to improve diagnostics in the case where an out-of-line 2147/// function definition doesn't match any declaration within 2148/// the class or namespace. 2149static bool isNearlyMatchingFunction(ASTContext &Context, 2150 FunctionDecl *Declaration, 2151 FunctionDecl *Definition) { 2152 if (Declaration->param_size() != Definition->param_size()) 2153 return false; 2154 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2155 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2156 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2157 2158 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2159 DefParamTy.getNonReferenceType())) 2160 return false; 2161 } 2162 2163 return true; 2164} 2165 2166Sema::DeclPtrTy 2167Sema::HandleDeclarator(Scope *S, Declarator &D, 2168 MultiTemplateParamsArg TemplateParamLists, 2169 bool IsFunctionDefinition) { 2170 DeclarationName Name = GetNameForDeclarator(D); 2171 2172 // All of these full declarators require an identifier. If it doesn't have 2173 // one, the ParsedFreeStandingDeclSpec action should be used. 2174 if (!Name) { 2175 if (!D.isInvalidType()) // Reject this if we think it is valid. 2176 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2177 diag::err_declarator_need_ident) 2178 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2179 return DeclPtrTy(); 2180 } 2181 2182 // The scope passed in may not be a decl scope. Zip up the scope tree until 2183 // we find one that is. 2184 while ((S->getFlags() & Scope::DeclScope) == 0 || 2185 (S->getFlags() & Scope::TemplateParamScope) != 0) 2186 S = S->getParent(); 2187 2188 // If this is an out-of-line definition of a member of a class template 2189 // or class template partial specialization, we may need to rebuild the 2190 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 2191 // for more information. 2192 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 2193 // handle expressions properly. 2194 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 2195 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 2196 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 2197 (DS.getTypeSpecType() == DeclSpec::TST_typename || 2198 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 2199 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 2200 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 2201 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 2202 // FIXME: Preserve type source info. 2203 QualType T = GetTypeFromParser(DS.getTypeRep()); 2204 2205 DeclContext *SavedContext = CurContext; 2206 CurContext = DC; 2207 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 2208 CurContext = SavedContext; 2209 2210 if (T.isNull()) 2211 return DeclPtrTy(); 2212 DS.UpdateTypeRep(T.getAsOpaquePtr()); 2213 } 2214 } 2215 2216 DeclContext *DC; 2217 NamedDecl *New; 2218 2219 TypeSourceInfo *TInfo = 0; 2220 QualType R = GetTypeForDeclarator(D, S, &TInfo); 2221 2222 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2223 ForRedeclaration); 2224 2225 // See if this is a redefinition of a variable in the same scope. 2226 if (D.getCXXScopeSpec().isInvalid()) { 2227 DC = CurContext; 2228 D.setInvalidType(); 2229 } else if (!D.getCXXScopeSpec().isSet()) { 2230 bool IsLinkageLookup = false; 2231 2232 // If the declaration we're planning to build will be a function 2233 // or object with linkage, then look for another declaration with 2234 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2235 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2236 /* Do nothing*/; 2237 else if (R->isFunctionType()) { 2238 if (CurContext->isFunctionOrMethod() || 2239 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2240 IsLinkageLookup = true; 2241 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2242 IsLinkageLookup = true; 2243 else if (CurContext->getLookupContext()->isTranslationUnit() && 2244 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2245 IsLinkageLookup = true; 2246 2247 if (IsLinkageLookup) 2248 Previous.clear(LookupRedeclarationWithLinkage); 2249 2250 DC = CurContext; 2251 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2252 } else { // Something like "int foo::x;" 2253 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2254 2255 if (!DC) { 2256 // If we could not compute the declaration context, it's because the 2257 // declaration context is dependent but does not refer to a class, 2258 // class template, or class template partial specialization. Complain 2259 // and return early, to avoid the coming semantic disaster. 2260 Diag(D.getIdentifierLoc(), 2261 diag::err_template_qualified_declarator_no_match) 2262 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2263 << D.getCXXScopeSpec().getRange(); 2264 return DeclPtrTy(); 2265 } 2266 2267 if (!DC->isDependentContext() && 2268 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2269 return DeclPtrTy(); 2270 2271 LookupQualifiedName(Previous, DC); 2272 2273 // Don't consider using declarations as previous declarations for 2274 // out-of-line members. 2275 RemoveUsingDecls(Previous); 2276 2277 // C++ 7.3.1.2p2: 2278 // Members (including explicit specializations of templates) of a named 2279 // namespace can also be defined outside that namespace by explicit 2280 // qualification of the name being defined, provided that the entity being 2281 // defined was already declared in the namespace and the definition appears 2282 // after the point of declaration in a namespace that encloses the 2283 // declarations namespace. 2284 // 2285 // Note that we only check the context at this point. We don't yet 2286 // have enough information to make sure that PrevDecl is actually 2287 // the declaration we want to match. For example, given: 2288 // 2289 // class X { 2290 // void f(); 2291 // void f(float); 2292 // }; 2293 // 2294 // void X::f(int) { } // ill-formed 2295 // 2296 // In this case, PrevDecl will point to the overload set 2297 // containing the two f's declared in X, but neither of them 2298 // matches. 2299 2300 // First check whether we named the global scope. 2301 if (isa<TranslationUnitDecl>(DC)) { 2302 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2303 << Name << D.getCXXScopeSpec().getRange(); 2304 } else { 2305 DeclContext *Cur = CurContext; 2306 while (isa<LinkageSpecDecl>(Cur)) 2307 Cur = Cur->getParent(); 2308 if (!Cur->Encloses(DC)) { 2309 // The qualifying scope doesn't enclose the original declaration. 2310 // Emit diagnostic based on current scope. 2311 SourceLocation L = D.getIdentifierLoc(); 2312 SourceRange R = D.getCXXScopeSpec().getRange(); 2313 if (isa<FunctionDecl>(Cur)) 2314 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2315 else 2316 Diag(L, diag::err_invalid_declarator_scope) 2317 << Name << cast<NamedDecl>(DC) << R; 2318 D.setInvalidType(); 2319 } 2320 } 2321 } 2322 2323 if (Previous.isSingleResult() && 2324 Previous.getFoundDecl()->isTemplateParameter()) { 2325 // Maybe we will complain about the shadowed template parameter. 2326 if (!D.isInvalidType()) 2327 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2328 Previous.getFoundDecl())) 2329 D.setInvalidType(); 2330 2331 // Just pretend that we didn't see the previous declaration. 2332 Previous.clear(); 2333 } 2334 2335 // In C++, the previous declaration we find might be a tag type 2336 // (class or enum). In this case, the new declaration will hide the 2337 // tag type. Note that this does does not apply if we're declaring a 2338 // typedef (C++ [dcl.typedef]p4). 2339 if (Previous.isSingleTagDecl() && 2340 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2341 Previous.clear(); 2342 2343 bool Redeclaration = false; 2344 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2345 if (TemplateParamLists.size()) { 2346 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2347 return DeclPtrTy(); 2348 } 2349 2350 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2351 } else if (R->isFunctionType()) { 2352 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2353 move(TemplateParamLists), 2354 IsFunctionDefinition, Redeclaration); 2355 } else { 2356 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2357 move(TemplateParamLists), 2358 Redeclaration); 2359 } 2360 2361 if (New == 0) 2362 return DeclPtrTy(); 2363 2364 // If this has an identifier and is not an invalid redeclaration or 2365 // function template specialization, add it to the scope stack. 2366 if (Name && !(Redeclaration && New->isInvalidDecl())) 2367 PushOnScopeChains(New, S); 2368 2369 return DeclPtrTy::make(New); 2370} 2371 2372/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2373/// types into constant array types in certain situations which would otherwise 2374/// be errors (for GCC compatibility). 2375static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2376 ASTContext &Context, 2377 bool &SizeIsNegative) { 2378 // This method tries to turn a variable array into a constant 2379 // array even when the size isn't an ICE. This is necessary 2380 // for compatibility with code that depends on gcc's buggy 2381 // constant expression folding, like struct {char x[(int)(char*)2];} 2382 SizeIsNegative = false; 2383 2384 QualifierCollector Qs; 2385 const Type *Ty = Qs.strip(T); 2386 2387 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2388 QualType Pointee = PTy->getPointeeType(); 2389 QualType FixedType = 2390 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2391 if (FixedType.isNull()) return FixedType; 2392 FixedType = Context.getPointerType(FixedType); 2393 return Qs.apply(FixedType); 2394 } 2395 2396 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2397 if (!VLATy) 2398 return QualType(); 2399 // FIXME: We should probably handle this case 2400 if (VLATy->getElementType()->isVariablyModifiedType()) 2401 return QualType(); 2402 2403 Expr::EvalResult EvalResult; 2404 if (!VLATy->getSizeExpr() || 2405 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2406 !EvalResult.Val.isInt()) 2407 return QualType(); 2408 2409 llvm::APSInt &Res = EvalResult.Val.getInt(); 2410 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2411 // TODO: preserve the size expression in declarator info 2412 return Context.getConstantArrayType(VLATy->getElementType(), 2413 Res, ArrayType::Normal, 0); 2414 } 2415 2416 SizeIsNegative = true; 2417 return QualType(); 2418} 2419 2420/// \brief Register the given locally-scoped external C declaration so 2421/// that it can be found later for redeclarations 2422void 2423Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2424 const LookupResult &Previous, 2425 Scope *S) { 2426 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2427 "Decl is not a locally-scoped decl!"); 2428 // Note that we have a locally-scoped external with this name. 2429 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2430 2431 if (!Previous.isSingleResult()) 2432 return; 2433 2434 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2435 2436 // If there was a previous declaration of this variable, it may be 2437 // in our identifier chain. Update the identifier chain with the new 2438 // declaration. 2439 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2440 // The previous declaration was found on the identifer resolver 2441 // chain, so remove it from its scope. 2442 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2443 S = S->getParent(); 2444 2445 if (S) 2446 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2447 } 2448} 2449 2450/// \brief Diagnose function specifiers on a declaration of an identifier that 2451/// does not identify a function. 2452void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2453 // FIXME: We should probably indicate the identifier in question to avoid 2454 // confusion for constructs like "inline int a(), b;" 2455 if (D.getDeclSpec().isInlineSpecified()) 2456 Diag(D.getDeclSpec().getInlineSpecLoc(), 2457 diag::err_inline_non_function); 2458 2459 if (D.getDeclSpec().isVirtualSpecified()) 2460 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2461 diag::err_virtual_non_function); 2462 2463 if (D.getDeclSpec().isExplicitSpecified()) 2464 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2465 diag::err_explicit_non_function); 2466} 2467 2468NamedDecl* 2469Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2470 QualType R, TypeSourceInfo *TInfo, 2471 LookupResult &Previous, bool &Redeclaration) { 2472 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2473 if (D.getCXXScopeSpec().isSet()) { 2474 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2475 << D.getCXXScopeSpec().getRange(); 2476 D.setInvalidType(); 2477 // Pretend we didn't see the scope specifier. 2478 DC = 0; 2479 } 2480 2481 if (getLangOptions().CPlusPlus) { 2482 // Check that there are no default arguments (C++ only). 2483 CheckExtraCXXDefaultArguments(D); 2484 } 2485 2486 DiagnoseFunctionSpecifiers(D); 2487 2488 if (D.getDeclSpec().isThreadSpecified()) 2489 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2490 2491 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2492 if (!NewTD) return 0; 2493 2494 // Handle attributes prior to checking for duplicates in MergeVarDecl 2495 ProcessDeclAttributes(S, NewTD, D); 2496 2497 // Merge the decl with the existing one if appropriate. If the decl is 2498 // in an outer scope, it isn't the same thing. 2499 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2500 if (!Previous.empty()) { 2501 Redeclaration = true; 2502 MergeTypeDefDecl(NewTD, Previous); 2503 } 2504 2505 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2506 // then it shall have block scope. 2507 QualType T = NewTD->getUnderlyingType(); 2508 if (T->isVariablyModifiedType()) { 2509 CurFunctionNeedsScopeChecking = true; 2510 2511 if (S->getFnParent() == 0) { 2512 bool SizeIsNegative; 2513 QualType FixedTy = 2514 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2515 if (!FixedTy.isNull()) { 2516 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2517 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2518 } else { 2519 if (SizeIsNegative) 2520 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2521 else if (T->isVariableArrayType()) 2522 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2523 else 2524 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2525 NewTD->setInvalidDecl(); 2526 } 2527 } 2528 } 2529 2530 // If this is the C FILE type, notify the AST context. 2531 if (IdentifierInfo *II = NewTD->getIdentifier()) 2532 if (!NewTD->isInvalidDecl() && 2533 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2534 if (II->isStr("FILE")) 2535 Context.setFILEDecl(NewTD); 2536 else if (II->isStr("jmp_buf")) 2537 Context.setjmp_bufDecl(NewTD); 2538 else if (II->isStr("sigjmp_buf")) 2539 Context.setsigjmp_bufDecl(NewTD); 2540 } 2541 2542 return NewTD; 2543} 2544 2545/// \brief Determines whether the given declaration is an out-of-scope 2546/// previous declaration. 2547/// 2548/// This routine should be invoked when name lookup has found a 2549/// previous declaration (PrevDecl) that is not in the scope where a 2550/// new declaration by the same name is being introduced. If the new 2551/// declaration occurs in a local scope, previous declarations with 2552/// linkage may still be considered previous declarations (C99 2553/// 6.2.2p4-5, C++ [basic.link]p6). 2554/// 2555/// \param PrevDecl the previous declaration found by name 2556/// lookup 2557/// 2558/// \param DC the context in which the new declaration is being 2559/// declared. 2560/// 2561/// \returns true if PrevDecl is an out-of-scope previous declaration 2562/// for a new delcaration with the same name. 2563static bool 2564isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2565 ASTContext &Context) { 2566 if (!PrevDecl) 2567 return 0; 2568 2569 if (!PrevDecl->hasLinkage()) 2570 return false; 2571 2572 if (Context.getLangOptions().CPlusPlus) { 2573 // C++ [basic.link]p6: 2574 // If there is a visible declaration of an entity with linkage 2575 // having the same name and type, ignoring entities declared 2576 // outside the innermost enclosing namespace scope, the block 2577 // scope declaration declares that same entity and receives the 2578 // linkage of the previous declaration. 2579 DeclContext *OuterContext = DC->getLookupContext(); 2580 if (!OuterContext->isFunctionOrMethod()) 2581 // This rule only applies to block-scope declarations. 2582 return false; 2583 else { 2584 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2585 if (PrevOuterContext->isRecord()) 2586 // We found a member function: ignore it. 2587 return false; 2588 else { 2589 // Find the innermost enclosing namespace for the new and 2590 // previous declarations. 2591 while (!OuterContext->isFileContext()) 2592 OuterContext = OuterContext->getParent(); 2593 while (!PrevOuterContext->isFileContext()) 2594 PrevOuterContext = PrevOuterContext->getParent(); 2595 2596 // The previous declaration is in a different namespace, so it 2597 // isn't the same function. 2598 if (OuterContext->getPrimaryContext() != 2599 PrevOuterContext->getPrimaryContext()) 2600 return false; 2601 } 2602 } 2603 } 2604 2605 return true; 2606} 2607 2608NamedDecl* 2609Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2610 QualType R, TypeSourceInfo *TInfo, 2611 LookupResult &Previous, 2612 MultiTemplateParamsArg TemplateParamLists, 2613 bool &Redeclaration) { 2614 DeclarationName Name = GetNameForDeclarator(D); 2615 2616 // Check that there are no default arguments (C++ only). 2617 if (getLangOptions().CPlusPlus) 2618 CheckExtraCXXDefaultArguments(D); 2619 2620 VarDecl *NewVD; 2621 VarDecl::StorageClass SC; 2622 switch (D.getDeclSpec().getStorageClassSpec()) { 2623 default: assert(0 && "Unknown storage class!"); 2624 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2625 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2626 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2627 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2628 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2629 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2630 case DeclSpec::SCS_mutable: 2631 // mutable can only appear on non-static class members, so it's always 2632 // an error here 2633 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2634 D.setInvalidType(); 2635 SC = VarDecl::None; 2636 break; 2637 } 2638 2639 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2640 if (!II) { 2641 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2642 << Name.getAsString(); 2643 return 0; 2644 } 2645 2646 DiagnoseFunctionSpecifiers(D); 2647 2648 if (!DC->isRecord() && S->getFnParent() == 0) { 2649 // C99 6.9p2: The storage-class specifiers auto and register shall not 2650 // appear in the declaration specifiers in an external declaration. 2651 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2652 2653 // If this is a register variable with an asm label specified, then this 2654 // is a GNU extension. 2655 if (SC == VarDecl::Register && D.getAsmLabel()) 2656 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2657 else 2658 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2659 D.setInvalidType(); 2660 } 2661 } 2662 if (DC->isRecord() && !CurContext->isRecord()) { 2663 // This is an out-of-line definition of a static data member. 2664 if (SC == VarDecl::Static) { 2665 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2666 diag::err_static_out_of_line) 2667 << CodeModificationHint::CreateRemoval( 2668 D.getDeclSpec().getStorageClassSpecLoc()); 2669 } else if (SC == VarDecl::None) 2670 SC = VarDecl::Static; 2671 } 2672 if (SC == VarDecl::Static) { 2673 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2674 if (RD->isLocalClass()) 2675 Diag(D.getIdentifierLoc(), 2676 diag::err_static_data_member_not_allowed_in_local_class) 2677 << Name << RD->getDeclName(); 2678 } 2679 } 2680 2681 // Match up the template parameter lists with the scope specifier, then 2682 // determine whether we have a template or a template specialization. 2683 bool isExplicitSpecialization = false; 2684 if (TemplateParameterList *TemplateParams 2685 = MatchTemplateParametersToScopeSpecifier( 2686 D.getDeclSpec().getSourceRange().getBegin(), 2687 D.getCXXScopeSpec(), 2688 (TemplateParameterList**)TemplateParamLists.get(), 2689 TemplateParamLists.size(), 2690 isExplicitSpecialization)) { 2691 if (TemplateParams->size() > 0) { 2692 // There is no such thing as a variable template. 2693 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2694 << II 2695 << SourceRange(TemplateParams->getTemplateLoc(), 2696 TemplateParams->getRAngleLoc()); 2697 return 0; 2698 } else { 2699 // There is an extraneous 'template<>' for this variable. Complain 2700 // about it, but allow the declaration of the variable. 2701 Diag(TemplateParams->getTemplateLoc(), 2702 diag::err_template_variable_noparams) 2703 << II 2704 << SourceRange(TemplateParams->getTemplateLoc(), 2705 TemplateParams->getRAngleLoc()); 2706 2707 isExplicitSpecialization = true; 2708 } 2709 } 2710 2711 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2712 II, R, TInfo, SC); 2713 2714 if (D.isInvalidType()) 2715 NewVD->setInvalidDecl(); 2716 2717 if (D.getDeclSpec().isThreadSpecified()) { 2718 if (NewVD->hasLocalStorage()) 2719 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2720 else if (!Context.Target.isTLSSupported()) 2721 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2722 else 2723 NewVD->setThreadSpecified(true); 2724 } 2725 2726 // Set the lexical context. If the declarator has a C++ scope specifier, the 2727 // lexical context will be different from the semantic context. 2728 NewVD->setLexicalDeclContext(CurContext); 2729 2730 // Handle attributes prior to checking for duplicates in MergeVarDecl 2731 ProcessDeclAttributes(S, NewVD, D); 2732 2733 // Handle GNU asm-label extension (encoded as an attribute). 2734 if (Expr *E = (Expr*) D.getAsmLabel()) { 2735 // The parser guarantees this is a string. 2736 StringLiteral *SE = cast<StringLiteral>(E); 2737 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2738 } 2739 2740 // Don't consider existing declarations that are in a different 2741 // scope and are out-of-semantic-context declarations (if the new 2742 // declaration has linkage). 2743 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2744 2745 // Merge the decl with the existing one if appropriate. 2746 if (!Previous.empty()) { 2747 if (Previous.isSingleResult() && 2748 isa<FieldDecl>(Previous.getFoundDecl()) && 2749 D.getCXXScopeSpec().isSet()) { 2750 // The user tried to define a non-static data member 2751 // out-of-line (C++ [dcl.meaning]p1). 2752 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2753 << D.getCXXScopeSpec().getRange(); 2754 Previous.clear(); 2755 NewVD->setInvalidDecl(); 2756 } 2757 } else if (D.getCXXScopeSpec().isSet()) { 2758 // No previous declaration in the qualifying scope. 2759 Diag(D.getIdentifierLoc(), diag::err_no_member) 2760 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2761 << D.getCXXScopeSpec().getRange(); 2762 NewVD->setInvalidDecl(); 2763 } 2764 2765 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2766 2767 // This is an explicit specialization of a static data member. Check it. 2768 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2769 CheckMemberSpecialization(NewVD, Previous)) 2770 NewVD->setInvalidDecl(); 2771 2772 // attributes declared post-definition are currently ignored 2773 if (Previous.isSingleResult()) { 2774 const VarDecl *Def = 0; 2775 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2776 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2777 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2778 Diag(Def->getLocation(), diag::note_previous_definition); 2779 } 2780 } 2781 2782 // If this is a locally-scoped extern C variable, update the map of 2783 // such variables. 2784 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2785 !NewVD->isInvalidDecl()) 2786 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2787 2788 return NewVD; 2789} 2790 2791/// \brief Perform semantic checking on a newly-created variable 2792/// declaration. 2793/// 2794/// This routine performs all of the type-checking required for a 2795/// variable declaration once it has been built. It is used both to 2796/// check variables after they have been parsed and their declarators 2797/// have been translated into a declaration, and to check variables 2798/// that have been instantiated from a template. 2799/// 2800/// Sets NewVD->isInvalidDecl() if an error was encountered. 2801void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2802 LookupResult &Previous, 2803 bool &Redeclaration) { 2804 // If the decl is already known invalid, don't check it. 2805 if (NewVD->isInvalidDecl()) 2806 return; 2807 2808 QualType T = NewVD->getType(); 2809 2810 if (T->isObjCInterfaceType()) { 2811 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2812 return NewVD->setInvalidDecl(); 2813 } 2814 2815 // Emit an error if an address space was applied to decl with local storage. 2816 // This includes arrays of objects with address space qualifiers, but not 2817 // automatic variables that point to other address spaces. 2818 // ISO/IEC TR 18037 S5.1.2 2819 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2820 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2821 return NewVD->setInvalidDecl(); 2822 } 2823 2824 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2825 && !NewVD->hasAttr<BlocksAttr>()) 2826 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2827 2828 bool isVM = T->isVariablyModifiedType(); 2829 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2830 NewVD->hasAttr<BlocksAttr>()) 2831 CurFunctionNeedsScopeChecking = true; 2832 2833 if ((isVM && NewVD->hasLinkage()) || 2834 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2835 bool SizeIsNegative; 2836 QualType FixedTy = 2837 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2838 2839 if (FixedTy.isNull() && T->isVariableArrayType()) { 2840 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2841 // FIXME: This won't give the correct result for 2842 // int a[10][n]; 2843 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2844 2845 if (NewVD->isFileVarDecl()) 2846 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2847 << SizeRange; 2848 else if (NewVD->getStorageClass() == VarDecl::Static) 2849 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2850 << SizeRange; 2851 else 2852 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2853 << SizeRange; 2854 return NewVD->setInvalidDecl(); 2855 } 2856 2857 if (FixedTy.isNull()) { 2858 if (NewVD->isFileVarDecl()) 2859 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2860 else 2861 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2862 return NewVD->setInvalidDecl(); 2863 } 2864 2865 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2866 NewVD->setType(FixedTy); 2867 } 2868 2869 if (Previous.empty() && NewVD->isExternC()) { 2870 // Since we did not find anything by this name and we're declaring 2871 // an extern "C" variable, look for a non-visible extern "C" 2872 // declaration with the same name. 2873 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2874 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2875 if (Pos != LocallyScopedExternalDecls.end()) 2876 Previous.addDecl(Pos->second); 2877 } 2878 2879 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2880 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2881 << T; 2882 return NewVD->setInvalidDecl(); 2883 } 2884 2885 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2886 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2887 return NewVD->setInvalidDecl(); 2888 } 2889 2890 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2891 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2892 return NewVD->setInvalidDecl(); 2893 } 2894 2895 if (!Previous.empty()) { 2896 Redeclaration = true; 2897 MergeVarDecl(NewVD, Previous); 2898 } 2899} 2900 2901/// \brief Data used with FindOverriddenMethod 2902struct FindOverriddenMethodData { 2903 Sema *S; 2904 CXXMethodDecl *Method; 2905}; 2906 2907/// \brief Member lookup function that determines whether a given C++ 2908/// method overrides a method in a base class, to be used with 2909/// CXXRecordDecl::lookupInBases(). 2910static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2911 CXXBasePath &Path, 2912 void *UserData) { 2913 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2914 2915 FindOverriddenMethodData *Data 2916 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2917 2918 DeclarationName Name = Data->Method->getDeclName(); 2919 2920 // FIXME: Do we care about other names here too? 2921 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2922 // We really want to find the base class constructor here. 2923 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2924 CanQualType CT = Data->S->Context.getCanonicalType(T); 2925 2926 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2927 } 2928 2929 for (Path.Decls = BaseRecord->lookup(Name); 2930 Path.Decls.first != Path.Decls.second; 2931 ++Path.Decls.first) { 2932 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2933 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2934 return true; 2935 } 2936 } 2937 2938 return false; 2939} 2940 2941/// AddOverriddenMethods - See if a method overrides any in the base classes, 2942/// and if so, check that it's a valid override and remember it. 2943void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2944 // Look for virtual methods in base classes that this method might override. 2945 CXXBasePaths Paths; 2946 FindOverriddenMethodData Data; 2947 Data.Method = MD; 2948 Data.S = this; 2949 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2950 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2951 E = Paths.found_decls_end(); I != E; ++I) { 2952 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2953 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2954 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2955 !CheckOverridingFunctionAttributes(MD, OldMD)) 2956 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2957 } 2958 } 2959 } 2960} 2961 2962NamedDecl* 2963Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2964 QualType R, TypeSourceInfo *TInfo, 2965 LookupResult &Previous, 2966 MultiTemplateParamsArg TemplateParamLists, 2967 bool IsFunctionDefinition, bool &Redeclaration) { 2968 assert(R.getTypePtr()->isFunctionType()); 2969 2970 DeclarationName Name = GetNameForDeclarator(D); 2971 FunctionDecl::StorageClass SC = FunctionDecl::None; 2972 switch (D.getDeclSpec().getStorageClassSpec()) { 2973 default: assert(0 && "Unknown storage class!"); 2974 case DeclSpec::SCS_auto: 2975 case DeclSpec::SCS_register: 2976 case DeclSpec::SCS_mutable: 2977 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2978 diag::err_typecheck_sclass_func); 2979 D.setInvalidType(); 2980 break; 2981 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2982 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2983 case DeclSpec::SCS_static: { 2984 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2985 // C99 6.7.1p5: 2986 // The declaration of an identifier for a function that has 2987 // block scope shall have no explicit storage-class specifier 2988 // other than extern 2989 // See also (C++ [dcl.stc]p4). 2990 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2991 diag::err_static_block_func); 2992 SC = FunctionDecl::None; 2993 } else 2994 SC = FunctionDecl::Static; 2995 break; 2996 } 2997 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2998 } 2999 3000 if (D.getDeclSpec().isThreadSpecified()) 3001 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3002 3003 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3004 bool isInline = D.getDeclSpec().isInlineSpecified(); 3005 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3006 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3007 3008 // Check that the return type is not an abstract class type. 3009 // For record types, this is done by the AbstractClassUsageDiagnoser once 3010 // the class has been completely parsed. 3011 if (!DC->isRecord() && 3012 RequireNonAbstractType(D.getIdentifierLoc(), 3013 R->getAs<FunctionType>()->getResultType(), 3014 diag::err_abstract_type_in_decl, 3015 AbstractReturnType)) 3016 D.setInvalidType(); 3017 3018 // Do not allow returning a objc interface by-value. 3019 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 3020 Diag(D.getIdentifierLoc(), 3021 diag::err_object_cannot_be_passed_returned_by_value) << 0 3022 << R->getAs<FunctionType>()->getResultType(); 3023 D.setInvalidType(); 3024 } 3025 3026 bool isVirtualOkay = false; 3027 FunctionDecl *NewFD; 3028 3029 if (isFriend) { 3030 // C++ [class.friend]p5 3031 // A function can be defined in a friend declaration of a 3032 // class . . . . Such a function is implicitly inline. 3033 isInline |= IsFunctionDefinition; 3034 } 3035 3036 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3037 // This is a C++ constructor declaration. 3038 assert(DC->isRecord() && 3039 "Constructors can only be declared in a member context"); 3040 3041 R = CheckConstructorDeclarator(D, R, SC); 3042 3043 // Create the new declaration 3044 NewFD = CXXConstructorDecl::Create(Context, 3045 cast<CXXRecordDecl>(DC), 3046 D.getIdentifierLoc(), Name, R, TInfo, 3047 isExplicit, isInline, 3048 /*isImplicitlyDeclared=*/false); 3049 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3050 // This is a C++ destructor declaration. 3051 if (DC->isRecord()) { 3052 R = CheckDestructorDeclarator(D, SC); 3053 3054 NewFD = CXXDestructorDecl::Create(Context, 3055 cast<CXXRecordDecl>(DC), 3056 D.getIdentifierLoc(), Name, R, 3057 isInline, 3058 /*isImplicitlyDeclared=*/false); 3059 3060 isVirtualOkay = true; 3061 } else { 3062 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3063 3064 // Create a FunctionDecl to satisfy the function definition parsing 3065 // code path. 3066 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3067 Name, R, TInfo, SC, isInline, 3068 /*hasPrototype=*/true); 3069 D.setInvalidType(); 3070 } 3071 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3072 if (!DC->isRecord()) { 3073 Diag(D.getIdentifierLoc(), 3074 diag::err_conv_function_not_member); 3075 return 0; 3076 } 3077 3078 CheckConversionDeclarator(D, R, SC); 3079 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3080 D.getIdentifierLoc(), Name, R, TInfo, 3081 isInline, isExplicit); 3082 3083 isVirtualOkay = true; 3084 } else if (DC->isRecord()) { 3085 // If the of the function is the same as the name of the record, then this 3086 // must be an invalid constructor that has a return type. 3087 // (The parser checks for a return type and makes the declarator a 3088 // constructor if it has no return type). 3089 // must have an invalid constructor that has a return type 3090 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3091 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3092 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3093 << SourceRange(D.getIdentifierLoc()); 3094 return 0; 3095 } 3096 3097 bool isStatic = SC == FunctionDecl::Static; 3098 3099 // [class.free]p1: 3100 // Any allocation function for a class T is a static member 3101 // (even if not explicitly declared static). 3102 if (Name.getCXXOverloadedOperator() == OO_New || 3103 Name.getCXXOverloadedOperator() == OO_Array_New) 3104 isStatic = true; 3105 3106 // [class.free]p6 Any deallocation function for a class X is a static member 3107 // (even if not explicitly declared static). 3108 if (Name.getCXXOverloadedOperator() == OO_Delete || 3109 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3110 isStatic = true; 3111 3112 // This is a C++ method declaration. 3113 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3114 D.getIdentifierLoc(), Name, R, TInfo, 3115 isStatic, isInline); 3116 3117 isVirtualOkay = !isStatic; 3118 } else { 3119 // Determine whether the function was written with a 3120 // prototype. This true when: 3121 // - we're in C++ (where every function has a prototype), 3122 // - there is a prototype in the declarator, or 3123 // - the type R of the function is some kind of typedef or other reference 3124 // to a type name (which eventually refers to a function type). 3125 bool HasPrototype = 3126 getLangOptions().CPlusPlus || 3127 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3128 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3129 3130 NewFD = FunctionDecl::Create(Context, DC, 3131 D.getIdentifierLoc(), 3132 Name, R, TInfo, SC, isInline, HasPrototype); 3133 } 3134 3135 if (D.isInvalidType()) 3136 NewFD->setInvalidDecl(); 3137 3138 // Set the lexical context. If the declarator has a C++ 3139 // scope specifier, or is the object of a friend declaration, the 3140 // lexical context will be different from the semantic context. 3141 NewFD->setLexicalDeclContext(CurContext); 3142 3143 // Match up the template parameter lists with the scope specifier, then 3144 // determine whether we have a template or a template specialization. 3145 FunctionTemplateDecl *FunctionTemplate = 0; 3146 bool isExplicitSpecialization = false; 3147 bool isFunctionTemplateSpecialization = false; 3148 if (TemplateParameterList *TemplateParams 3149 = MatchTemplateParametersToScopeSpecifier( 3150 D.getDeclSpec().getSourceRange().getBegin(), 3151 D.getCXXScopeSpec(), 3152 (TemplateParameterList**)TemplateParamLists.get(), 3153 TemplateParamLists.size(), 3154 isExplicitSpecialization)) { 3155 if (TemplateParams->size() > 0) { 3156 // This is a function template 3157 3158 // Check that we can declare a template here. 3159 if (CheckTemplateDeclScope(S, TemplateParams)) 3160 return 0; 3161 3162 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3163 NewFD->getLocation(), 3164 Name, TemplateParams, 3165 NewFD); 3166 FunctionTemplate->setLexicalDeclContext(CurContext); 3167 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3168 } else { 3169 // This is a function template specialization. 3170 isFunctionTemplateSpecialization = true; 3171 } 3172 3173 // FIXME: Free this memory properly. 3174 TemplateParamLists.release(); 3175 } 3176 3177 // C++ [dcl.fct.spec]p5: 3178 // The virtual specifier shall only be used in declarations of 3179 // nonstatic class member functions that appear within a 3180 // member-specification of a class declaration; see 10.3. 3181 // 3182 if (isVirtual && !NewFD->isInvalidDecl()) { 3183 if (!isVirtualOkay) { 3184 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3185 diag::err_virtual_non_function); 3186 } else if (!CurContext->isRecord()) { 3187 // 'virtual' was specified outside of the class. 3188 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3189 << CodeModificationHint::CreateRemoval( 3190 D.getDeclSpec().getVirtualSpecLoc()); 3191 } else { 3192 // Okay: Add virtual to the method. 3193 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3194 CurClass->setMethodAsVirtual(NewFD); 3195 } 3196 } 3197 3198 // Filter out previous declarations that don't match the scope. 3199 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3200 3201 if (isFriend) { 3202 // DC is the namespace in which the function is being declared. 3203 assert((DC->isFileContext() || !Previous.empty()) && 3204 "previously-undeclared friend function being created " 3205 "in a non-namespace context"); 3206 3207 if (FunctionTemplate) { 3208 FunctionTemplate->setObjectOfFriendDecl( 3209 /* PreviouslyDeclared= */ !Previous.empty()); 3210 FunctionTemplate->setAccess(AS_public); 3211 } 3212 else 3213 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 3214 3215 NewFD->setAccess(AS_public); 3216 } 3217 3218 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3219 !CurContext->isRecord()) { 3220 // C++ [class.static]p1: 3221 // A data or function member of a class may be declared static 3222 // in a class definition, in which case it is a static member of 3223 // the class. 3224 3225 // Complain about the 'static' specifier if it's on an out-of-line 3226 // member function definition. 3227 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3228 diag::err_static_out_of_line) 3229 << CodeModificationHint::CreateRemoval( 3230 D.getDeclSpec().getStorageClassSpecLoc()); 3231 } 3232 3233 // Handle GNU asm-label extension (encoded as an attribute). 3234 if (Expr *E = (Expr*) D.getAsmLabel()) { 3235 // The parser guarantees this is a string. 3236 StringLiteral *SE = cast<StringLiteral>(E); 3237 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 3238 } 3239 3240 // Copy the parameter declarations from the declarator D to the function 3241 // declaration NewFD, if they are available. First scavenge them into Params. 3242 llvm::SmallVector<ParmVarDecl*, 16> Params; 3243 if (D.getNumTypeObjects() > 0) { 3244 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3245 3246 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3247 // function that takes no arguments, not a function that takes a 3248 // single void argument. 3249 // We let through "const void" here because Sema::GetTypeForDeclarator 3250 // already checks for that case. 3251 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3252 FTI.ArgInfo[0].Param && 3253 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3254 // Empty arg list, don't push any params. 3255 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3256 3257 // In C++, the empty parameter-type-list must be spelled "void"; a 3258 // typedef of void is not permitted. 3259 if (getLangOptions().CPlusPlus && 3260 Param->getType().getUnqualifiedType() != Context.VoidTy) 3261 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3262 // FIXME: Leaks decl? 3263 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3264 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3265 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3266 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3267 Param->setDeclContext(NewFD); 3268 Params.push_back(Param); 3269 } 3270 } 3271 3272 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3273 // When we're declaring a function with a typedef, typeof, etc as in the 3274 // following example, we'll need to synthesize (unnamed) 3275 // parameters for use in the declaration. 3276 // 3277 // @code 3278 // typedef void fn(int); 3279 // fn f; 3280 // @endcode 3281 3282 // Synthesize a parameter for each argument type. 3283 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3284 AE = FT->arg_type_end(); AI != AE; ++AI) { 3285 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3286 SourceLocation(), 0, 3287 *AI, /*TInfo=*/0, 3288 VarDecl::None, 0); 3289 Param->setImplicit(); 3290 Params.push_back(Param); 3291 } 3292 } else { 3293 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3294 "Should not need args for typedef of non-prototype fn"); 3295 } 3296 // Finally, we know we have the right number of parameters, install them. 3297 NewFD->setParams(Context, Params.data(), Params.size()); 3298 3299 // If the declarator is a template-id, translate the parser's template 3300 // argument list into our AST format. 3301 bool HasExplicitTemplateArgs = false; 3302 TemplateArgumentListInfo TemplateArgs; 3303 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3304 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3305 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3306 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3307 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3308 TemplateId->getTemplateArgs(), 3309 TemplateId->NumArgs); 3310 translateTemplateArguments(TemplateArgsPtr, 3311 TemplateArgs); 3312 TemplateArgsPtr.release(); 3313 3314 HasExplicitTemplateArgs = true; 3315 3316 if (FunctionTemplate) { 3317 // FIXME: Diagnose function template with explicit template 3318 // arguments. 3319 HasExplicitTemplateArgs = false; 3320 } else if (!isFunctionTemplateSpecialization && 3321 !D.getDeclSpec().isFriendSpecified()) { 3322 // We have encountered something that the user meant to be a 3323 // specialization (because it has explicitly-specified template 3324 // arguments) but that was not introduced with a "template<>" (or had 3325 // too few of them). 3326 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3327 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3328 << CodeModificationHint::CreateInsertion( 3329 D.getDeclSpec().getSourceRange().getBegin(), 3330 "template<> "); 3331 isFunctionTemplateSpecialization = true; 3332 } 3333 } 3334 3335 if (isFunctionTemplateSpecialization) { 3336 if (CheckFunctionTemplateSpecialization(NewFD, 3337 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3338 Previous)) 3339 NewFD->setInvalidDecl(); 3340 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3341 CheckMemberSpecialization(NewFD, Previous)) 3342 NewFD->setInvalidDecl(); 3343 3344 // Perform semantic checking on the function declaration. 3345 bool OverloadableAttrRequired = false; // FIXME: HACK! 3346 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3347 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3348 3349 assert((NewFD->isInvalidDecl() || !Redeclaration || 3350 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3351 "previous declaration set still overloaded"); 3352 3353 // If we have a function template, check the template parameter 3354 // list. This will check and merge default template arguments. 3355 if (FunctionTemplate) { 3356 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3357 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3358 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3359 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3360 : TPC_FunctionTemplate); 3361 } 3362 3363 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3364 // An out-of-line member function declaration must also be a 3365 // definition (C++ [dcl.meaning]p1). 3366 // Note that this is not the case for explicit specializations of 3367 // function templates or member functions of class templates, per 3368 // C++ [temp.expl.spec]p2. 3369 if (!IsFunctionDefinition && !isFriend && 3370 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3371 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3372 << D.getCXXScopeSpec().getRange(); 3373 NewFD->setInvalidDecl(); 3374 } else if (!Redeclaration && 3375 !(isFriend && CurContext->isDependentContext())) { 3376 // The user tried to provide an out-of-line definition for a 3377 // function that is a member of a class or namespace, but there 3378 // was no such member function declared (C++ [class.mfct]p2, 3379 // C++ [namespace.memdef]p2). For example: 3380 // 3381 // class X { 3382 // void f() const; 3383 // }; 3384 // 3385 // void X::f() { } // ill-formed 3386 // 3387 // Complain about this problem, and attempt to suggest close 3388 // matches (e.g., those that differ only in cv-qualifiers and 3389 // whether the parameter types are references). 3390 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3391 << Name << DC << D.getCXXScopeSpec().getRange(); 3392 NewFD->setInvalidDecl(); 3393 3394 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3395 ForRedeclaration); 3396 LookupQualifiedName(Prev, DC); 3397 assert(!Prev.isAmbiguous() && 3398 "Cannot have an ambiguity in previous-declaration lookup"); 3399 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3400 Func != FuncEnd; ++Func) { 3401 if (isa<FunctionDecl>(*Func) && 3402 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3403 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3404 } 3405 } 3406 } 3407 3408 // Handle attributes. We need to have merged decls when handling attributes 3409 // (for example to check for conflicts, etc). 3410 // FIXME: This needs to happen before we merge declarations. Then, 3411 // let attribute merging cope with attribute conflicts. 3412 ProcessDeclAttributes(S, NewFD, D); 3413 3414 // attributes declared post-definition are currently ignored 3415 if (Redeclaration && Previous.isSingleResult()) { 3416 const FunctionDecl *Def; 3417 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3418 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3419 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3420 Diag(Def->getLocation(), diag::note_previous_definition); 3421 } 3422 } 3423 3424 AddKnownFunctionAttributes(NewFD); 3425 3426 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3427 // If a function name is overloadable in C, then every function 3428 // with that name must be marked "overloadable". 3429 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3430 << Redeclaration << NewFD; 3431 if (!Previous.empty()) 3432 Diag(Previous.getRepresentativeDecl()->getLocation(), 3433 diag::note_attribute_overloadable_prev_overload); 3434 NewFD->addAttr(::new (Context) OverloadableAttr()); 3435 } 3436 3437 // If this is a locally-scoped extern C function, update the 3438 // map of such names. 3439 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3440 && !NewFD->isInvalidDecl()) 3441 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3442 3443 // Set this FunctionDecl's range up to the right paren. 3444 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3445 3446 if (FunctionTemplate && NewFD->isInvalidDecl()) 3447 FunctionTemplate->setInvalidDecl(); 3448 3449 if (FunctionTemplate) 3450 return FunctionTemplate; 3451 3452 return NewFD; 3453} 3454 3455/// \brief Perform semantic checking of a new function declaration. 3456/// 3457/// Performs semantic analysis of the new function declaration 3458/// NewFD. This routine performs all semantic checking that does not 3459/// require the actual declarator involved in the declaration, and is 3460/// used both for the declaration of functions as they are parsed 3461/// (called via ActOnDeclarator) and for the declaration of functions 3462/// that have been instantiated via C++ template instantiation (called 3463/// via InstantiateDecl). 3464/// 3465/// \param IsExplicitSpecialiation whether this new function declaration is 3466/// an explicit specialization of the previous declaration. 3467/// 3468/// This sets NewFD->isInvalidDecl() to true if there was an error. 3469void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3470 LookupResult &Previous, 3471 bool IsExplicitSpecialization, 3472 bool &Redeclaration, 3473 bool &OverloadableAttrRequired) { 3474 // If NewFD is already known erroneous, don't do any of this checking. 3475 if (NewFD->isInvalidDecl()) 3476 return; 3477 3478 if (NewFD->getResultType()->isVariablyModifiedType()) { 3479 // Functions returning a variably modified type violate C99 6.7.5.2p2 3480 // because all functions have linkage. 3481 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3482 return NewFD->setInvalidDecl(); 3483 } 3484 3485 if (NewFD->isMain()) 3486 CheckMain(NewFD); 3487 3488 // Check for a previous declaration of this name. 3489 if (Previous.empty() && NewFD->isExternC()) { 3490 // Since we did not find anything by this name and we're declaring 3491 // an extern "C" function, look for a non-visible extern "C" 3492 // declaration with the same name. 3493 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3494 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3495 if (Pos != LocallyScopedExternalDecls.end()) 3496 Previous.addDecl(Pos->second); 3497 } 3498 3499 // Merge or overload the declaration with an existing declaration of 3500 // the same name, if appropriate. 3501 if (!Previous.empty()) { 3502 // Determine whether NewFD is an overload of PrevDecl or 3503 // a declaration that requires merging. If it's an overload, 3504 // there's no more work to do here; we'll just add the new 3505 // function to the scope. 3506 3507 NamedDecl *OldDecl = 0; 3508 if (!AllowOverloadingOfFunction(Previous, Context)) { 3509 Redeclaration = true; 3510 OldDecl = Previous.getFoundDecl(); 3511 } else { 3512 if (!getLangOptions().CPlusPlus) { 3513 OverloadableAttrRequired = true; 3514 3515 // Functions marked "overloadable" must have a prototype (that 3516 // we can't get through declaration merging). 3517 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3518 Diag(NewFD->getLocation(), 3519 diag::err_attribute_overloadable_no_prototype) 3520 << NewFD; 3521 Redeclaration = true; 3522 3523 // Turn this into a variadic function with no parameters. 3524 QualType R = Context.getFunctionType( 3525 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3526 0, 0, true, 0); 3527 NewFD->setType(R); 3528 return NewFD->setInvalidDecl(); 3529 } 3530 } 3531 3532 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3533 case Ovl_Match: 3534 Redeclaration = true; 3535 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3536 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3537 Redeclaration = false; 3538 } 3539 break; 3540 3541 case Ovl_NonFunction: 3542 Redeclaration = true; 3543 break; 3544 3545 case Ovl_Overload: 3546 Redeclaration = false; 3547 break; 3548 } 3549 } 3550 3551 if (Redeclaration) { 3552 // NewFD and OldDecl represent declarations that need to be 3553 // merged. 3554 if (MergeFunctionDecl(NewFD, OldDecl)) 3555 return NewFD->setInvalidDecl(); 3556 3557 Previous.clear(); 3558 Previous.addDecl(OldDecl); 3559 3560 if (FunctionTemplateDecl *OldTemplateDecl 3561 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3562 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3563 FunctionTemplateDecl *NewTemplateDecl 3564 = NewFD->getDescribedFunctionTemplate(); 3565 assert(NewTemplateDecl && "Template/non-template mismatch"); 3566 if (CXXMethodDecl *Method 3567 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3568 Method->setAccess(OldTemplateDecl->getAccess()); 3569 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3570 } 3571 3572 // If this is an explicit specialization of a member that is a function 3573 // template, mark it as a member specialization. 3574 if (IsExplicitSpecialization && 3575 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3576 NewTemplateDecl->setMemberSpecialization(); 3577 assert(OldTemplateDecl->isMemberSpecialization()); 3578 } 3579 } else { 3580 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3581 NewFD->setAccess(OldDecl->getAccess()); 3582 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3583 } 3584 } 3585 } 3586 3587 // Semantic checking for this function declaration (in isolation). 3588 if (getLangOptions().CPlusPlus) { 3589 // C++-specific checks. 3590 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3591 CheckConstructor(Constructor); 3592 } else if (CXXDestructorDecl *Destructor = 3593 dyn_cast<CXXDestructorDecl>(NewFD)) { 3594 CXXRecordDecl *Record = Destructor->getParent(); 3595 QualType ClassType = Context.getTypeDeclType(Record); 3596 3597 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3598 // type is dependent? Both gcc and edg can handle that. 3599 if (!ClassType->isDependentType()) { 3600 DeclarationName Name 3601 = Context.DeclarationNames.getCXXDestructorName( 3602 Context.getCanonicalType(ClassType)); 3603 if (NewFD->getDeclName() != Name) { 3604 Diag(NewFD->getLocation(), diag::err_destructor_name); 3605 return NewFD->setInvalidDecl(); 3606 } 3607 } 3608 3609 Record->setUserDeclaredDestructor(true); 3610 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3611 // user-defined destructor. 3612 Record->setPOD(false); 3613 3614 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3615 // declared destructor. 3616 // FIXME: C++0x: don't do this for "= default" destructors 3617 Record->setHasTrivialDestructor(false); 3618 } else if (CXXConversionDecl *Conversion 3619 = dyn_cast<CXXConversionDecl>(NewFD)) { 3620 ActOnConversionDeclarator(Conversion); 3621 } 3622 3623 // Find any virtual functions that this function overrides. 3624 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3625 if (!Method->isFunctionTemplateSpecialization() && 3626 !Method->getDescribedFunctionTemplate()) 3627 AddOverriddenMethods(Method->getParent(), Method); 3628 } 3629 3630 // Additional checks for the destructor; make sure we do this after we 3631 // figure out whether the destructor is virtual. 3632 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3633 if (!Destructor->getParent()->isDependentType()) 3634 CheckDestructor(Destructor); 3635 3636 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3637 if (NewFD->isOverloadedOperator() && 3638 CheckOverloadedOperatorDeclaration(NewFD)) 3639 return NewFD->setInvalidDecl(); 3640 3641 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3642 if (NewFD->getLiteralIdentifier() && 3643 CheckLiteralOperatorDeclaration(NewFD)) 3644 return NewFD->setInvalidDecl(); 3645 3646 // In C++, check default arguments now that we have merged decls. Unless 3647 // the lexical context is the class, because in this case this is done 3648 // during delayed parsing anyway. 3649 if (!CurContext->isRecord()) 3650 CheckCXXDefaultArguments(NewFD); 3651 } 3652} 3653 3654void Sema::CheckMain(FunctionDecl* FD) { 3655 // C++ [basic.start.main]p3: A program that declares main to be inline 3656 // or static is ill-formed. 3657 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3658 // shall not appear in a declaration of main. 3659 // static main is not an error under C99, but we should warn about it. 3660 bool isInline = FD->isInlineSpecified(); 3661 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3662 if (isInline || isStatic) { 3663 unsigned diagID = diag::warn_unusual_main_decl; 3664 if (isInline || getLangOptions().CPlusPlus) 3665 diagID = diag::err_unusual_main_decl; 3666 3667 int which = isStatic + (isInline << 1) - 1; 3668 Diag(FD->getLocation(), diagID) << which; 3669 } 3670 3671 QualType T = FD->getType(); 3672 assert(T->isFunctionType() && "function decl is not of function type"); 3673 const FunctionType* FT = T->getAs<FunctionType>(); 3674 3675 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3676 // TODO: add a replacement fixit to turn the return type into 'int'. 3677 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3678 FD->setInvalidDecl(true); 3679 } 3680 3681 // Treat protoless main() as nullary. 3682 if (isa<FunctionNoProtoType>(FT)) return; 3683 3684 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3685 unsigned nparams = FTP->getNumArgs(); 3686 assert(FD->getNumParams() == nparams); 3687 3688 bool HasExtraParameters = (nparams > 3); 3689 3690 // Darwin passes an undocumented fourth argument of type char**. If 3691 // other platforms start sprouting these, the logic below will start 3692 // getting shifty. 3693 if (nparams == 4 && 3694 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3695 HasExtraParameters = false; 3696 3697 if (HasExtraParameters) { 3698 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3699 FD->setInvalidDecl(true); 3700 nparams = 3; 3701 } 3702 3703 // FIXME: a lot of the following diagnostics would be improved 3704 // if we had some location information about types. 3705 3706 QualType CharPP = 3707 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3708 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3709 3710 for (unsigned i = 0; i < nparams; ++i) { 3711 QualType AT = FTP->getArgType(i); 3712 3713 bool mismatch = true; 3714 3715 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3716 mismatch = false; 3717 else if (Expected[i] == CharPP) { 3718 // As an extension, the following forms are okay: 3719 // char const ** 3720 // char const * const * 3721 // char * const * 3722 3723 QualifierCollector qs; 3724 const PointerType* PT; 3725 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3726 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3727 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3728 qs.removeConst(); 3729 mismatch = !qs.empty(); 3730 } 3731 } 3732 3733 if (mismatch) { 3734 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3735 // TODO: suggest replacing given type with expected type 3736 FD->setInvalidDecl(true); 3737 } 3738 } 3739 3740 if (nparams == 1 && !FD->isInvalidDecl()) { 3741 Diag(FD->getLocation(), diag::warn_main_one_arg); 3742 } 3743} 3744 3745bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3746 // FIXME: Need strict checking. In C89, we need to check for 3747 // any assignment, increment, decrement, function-calls, or 3748 // commas outside of a sizeof. In C99, it's the same list, 3749 // except that the aforementioned are allowed in unevaluated 3750 // expressions. Everything else falls under the 3751 // "may accept other forms of constant expressions" exception. 3752 // (We never end up here for C++, so the constant expression 3753 // rules there don't matter.) 3754 if (Init->isConstantInitializer(Context)) 3755 return false; 3756 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3757 << Init->getSourceRange(); 3758 return true; 3759} 3760 3761void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3762 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3763} 3764 3765/// AddInitializerToDecl - Adds the initializer Init to the 3766/// declaration dcl. If DirectInit is true, this is C++ direct 3767/// initialization rather than copy initialization. 3768void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3769 Decl *RealDecl = dcl.getAs<Decl>(); 3770 // If there is no declaration, there was an error parsing it. Just ignore 3771 // the initializer. 3772 if (RealDecl == 0) 3773 return; 3774 3775 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3776 // With declarators parsed the way they are, the parser cannot 3777 // distinguish between a normal initializer and a pure-specifier. 3778 // Thus this grotesque test. 3779 IntegerLiteral *IL; 3780 Expr *Init = static_cast<Expr *>(init.get()); 3781 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3782 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3783 CheckPureMethod(Method, Init->getSourceRange()); 3784 else { 3785 Diag(Method->getLocation(), diag::err_member_function_initialization) 3786 << Method->getDeclName() << Init->getSourceRange(); 3787 Method->setInvalidDecl(); 3788 } 3789 return; 3790 } 3791 3792 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3793 if (!VDecl) { 3794 if (getLangOptions().CPlusPlus && 3795 RealDecl->getLexicalDeclContext()->isRecord() && 3796 isa<NamedDecl>(RealDecl)) 3797 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3798 << cast<NamedDecl>(RealDecl)->getDeclName(); 3799 else 3800 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3801 RealDecl->setInvalidDecl(); 3802 return; 3803 } 3804 3805 // A definition must end up with a complete type, which means it must be 3806 // complete with the restriction that an array type might be completed by the 3807 // initializer; note that later code assumes this restriction. 3808 QualType BaseDeclType = VDecl->getType(); 3809 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3810 BaseDeclType = Array->getElementType(); 3811 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3812 diag::err_typecheck_decl_incomplete_type)) { 3813 RealDecl->setInvalidDecl(); 3814 return; 3815 } 3816 3817 // The variable can not have an abstract class type. 3818 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3819 diag::err_abstract_type_in_decl, 3820 AbstractVariableType)) 3821 VDecl->setInvalidDecl(); 3822 3823 const VarDecl *Def = 0; 3824 if (VDecl->getDefinition(Def)) { 3825 Diag(VDecl->getLocation(), diag::err_redefinition) 3826 << VDecl->getDeclName(); 3827 Diag(Def->getLocation(), diag::note_previous_definition); 3828 VDecl->setInvalidDecl(); 3829 return; 3830 } 3831 3832 // Take ownership of the expression, now that we're sure we have somewhere 3833 // to put it. 3834 Expr *Init = init.takeAs<Expr>(); 3835 assert(Init && "missing initializer"); 3836 3837 // Capture the variable that is being initialized and the style of 3838 // initialization. 3839 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3840 3841 // FIXME: Poor source location information. 3842 InitializationKind Kind 3843 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3844 Init->getLocStart(), 3845 Init->getLocEnd()) 3846 : InitializationKind::CreateCopy(VDecl->getLocation(), 3847 Init->getLocStart()); 3848 3849 // Get the decls type and save a reference for later, since 3850 // CheckInitializerTypes may change it. 3851 QualType DclT = VDecl->getType(), SavT = DclT; 3852 if (VDecl->isBlockVarDecl()) { 3853 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3854 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3855 VDecl->setInvalidDecl(); 3856 } else if (!VDecl->isInvalidDecl()) { 3857 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3858 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3859 MultiExprArg(*this, (void**)&Init, 1), 3860 &DclT); 3861 if (Result.isInvalid()) { 3862 VDecl->setInvalidDecl(); 3863 return; 3864 } 3865 3866 Init = Result.takeAs<Expr>(); 3867 3868 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3869 // Don't check invalid declarations to avoid emitting useless diagnostics. 3870 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3871 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3872 CheckForConstantInitializer(Init, DclT); 3873 } 3874 } 3875 } else if (VDecl->isStaticDataMember() && 3876 VDecl->getLexicalDeclContext()->isRecord()) { 3877 // This is an in-class initialization for a static data member, e.g., 3878 // 3879 // struct S { 3880 // static const int value = 17; 3881 // }; 3882 3883 // Attach the initializer 3884 VDecl->setInit(Context, Init); 3885 3886 // C++ [class.mem]p4: 3887 // A member-declarator can contain a constant-initializer only 3888 // if it declares a static member (9.4) of const integral or 3889 // const enumeration type, see 9.4.2. 3890 QualType T = VDecl->getType(); 3891 if (!T->isDependentType() && 3892 (!Context.getCanonicalType(T).isConstQualified() || 3893 !T->isIntegralType())) { 3894 Diag(VDecl->getLocation(), diag::err_member_initialization) 3895 << VDecl->getDeclName() << Init->getSourceRange(); 3896 VDecl->setInvalidDecl(); 3897 } else { 3898 // C++ [class.static.data]p4: 3899 // If a static data member is of const integral or const 3900 // enumeration type, its declaration in the class definition 3901 // can specify a constant-initializer which shall be an 3902 // integral constant expression (5.19). 3903 if (!Init->isTypeDependent() && 3904 !Init->getType()->isIntegralType()) { 3905 // We have a non-dependent, non-integral or enumeration type. 3906 Diag(Init->getSourceRange().getBegin(), 3907 diag::err_in_class_initializer_non_integral_type) 3908 << Init->getType() << Init->getSourceRange(); 3909 VDecl->setInvalidDecl(); 3910 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3911 // Check whether the expression is a constant expression. 3912 llvm::APSInt Value; 3913 SourceLocation Loc; 3914 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3915 Diag(Loc, diag::err_in_class_initializer_non_constant) 3916 << Init->getSourceRange(); 3917 VDecl->setInvalidDecl(); 3918 } else if (!VDecl->getType()->isDependentType()) 3919 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3920 } 3921 } 3922 } else if (VDecl->isFileVarDecl()) { 3923 if (VDecl->getStorageClass() == VarDecl::Extern) 3924 Diag(VDecl->getLocation(), diag::warn_extern_init); 3925 if (!VDecl->isInvalidDecl()) { 3926 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3927 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3928 MultiExprArg(*this, (void**)&Init, 1), 3929 &DclT); 3930 if (Result.isInvalid()) { 3931 VDecl->setInvalidDecl(); 3932 return; 3933 } 3934 3935 Init = Result.takeAs<Expr>(); 3936 } 3937 3938 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3939 // Don't check invalid declarations to avoid emitting useless diagnostics. 3940 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3941 // C99 6.7.8p4. All file scoped initializers need to be constant. 3942 CheckForConstantInitializer(Init, DclT); 3943 } 3944 } 3945 // If the type changed, it means we had an incomplete type that was 3946 // completed by the initializer. For example: 3947 // int ary[] = { 1, 3, 5 }; 3948 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3949 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3950 VDecl->setType(DclT); 3951 Init->setType(DclT); 3952 } 3953 3954 Init = MaybeCreateCXXExprWithTemporaries(Init); 3955 // Attach the initializer to the decl. 3956 VDecl->setInit(Context, Init); 3957 3958 // If the previous declaration of VDecl was a tentative definition, 3959 // remove it from the set of tentative definitions. 3960 if (VDecl->getPreviousDeclaration() && 3961 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3962 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3963 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3964 } 3965 3966 if (getLangOptions().CPlusPlus) { 3967 // Make sure we mark the destructor as used if necessary. 3968 QualType InitType = VDecl->getType(); 3969 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3970 InitType = Context.getBaseElementType(Array); 3971 if (InitType->isRecordType()) 3972 FinalizeVarWithDestructor(VDecl, InitType); 3973 } 3974 3975 return; 3976} 3977 3978void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3979 bool TypeContainsUndeducedAuto) { 3980 Decl *RealDecl = dcl.getAs<Decl>(); 3981 3982 // If there is no declaration, there was an error parsing it. Just ignore it. 3983 if (RealDecl == 0) 3984 return; 3985 3986 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3987 QualType Type = Var->getType(); 3988 3989 // Record tentative definitions. 3990 if (Var->isTentativeDefinition(Context)) { 3991 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3992 InsertPair = 3993 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3994 3995 // Keep the latest definition in the map. If we see 'int i; int i;' we 3996 // want the second one in the map. 3997 InsertPair.first->second = Var; 3998 3999 // However, for the list, we don't care about the order, just make sure 4000 // that there are no dupes for a given declaration name. 4001 if (InsertPair.second) 4002 TentativeDefinitionList.push_back(Var->getDeclName()); 4003 } 4004 4005 // C++ [dcl.init.ref]p3: 4006 // The initializer can be omitted for a reference only in a 4007 // parameter declaration (8.3.5), in the declaration of a 4008 // function return type, in the declaration of a class member 4009 // within its class declaration (9.2), and where the extern 4010 // specifier is explicitly used. 4011 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 4012 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4013 << Var->getDeclName() 4014 << SourceRange(Var->getLocation(), Var->getLocation()); 4015 Var->setInvalidDecl(); 4016 return; 4017 } 4018 4019 // C++0x [dcl.spec.auto]p3 4020 if (TypeContainsUndeducedAuto) { 4021 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4022 << Var->getDeclName() << Type; 4023 Var->setInvalidDecl(); 4024 return; 4025 } 4026 4027 // An array without size is an incomplete type, and there are no special 4028 // rules in C++ to make such a definition acceptable. 4029 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 4030 !Var->hasExternalStorage()) { 4031 Diag(Var->getLocation(), 4032 diag::err_typecheck_incomplete_array_needs_initializer); 4033 Var->setInvalidDecl(); 4034 return; 4035 } 4036 4037 // C++ [temp.expl.spec]p15: 4038 // An explicit specialization of a static data member of a template is a 4039 // definition if the declaration includes an initializer; otherwise, it 4040 // is a declaration. 4041 if (Var->isStaticDataMember() && 4042 Var->getInstantiatedFromStaticDataMember() && 4043 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 4044 return; 4045 4046 // C++ [dcl.init]p9: 4047 // If no initializer is specified for an object, and the object 4048 // is of (possibly cv-qualified) non-POD class type (or array 4049 // thereof), the object shall be default-initialized; if the 4050 // object is of const-qualified type, the underlying class type 4051 // shall have a user-declared default constructor. 4052 // 4053 // FIXME: Diagnose the "user-declared default constructor" bit. 4054 if (getLangOptions().CPlusPlus) { 4055 QualType InitType = Type; 4056 if (const ArrayType *Array = Context.getAsArrayType(Type)) 4057 InitType = Context.getBaseElementType(Array); 4058 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 4059 InitType->isRecordType() && !InitType->isDependentType()) { 4060 if (!RequireCompleteType(Var->getLocation(), InitType, 4061 diag::err_invalid_incomplete_type_use)) { 4062 InitializedEntity Entity 4063 = InitializedEntity::InitializeVariable(Var); 4064 InitializationKind Kind 4065 = InitializationKind::CreateDefault(Var->getLocation()); 4066 4067 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4068 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4069 MultiExprArg(*this, 0, 0)); 4070 if (Init.isInvalid()) 4071 Var->setInvalidDecl(); 4072 else { 4073 Var->setInit(Context, 4074 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4075 FinalizeVarWithDestructor(Var, InitType); 4076 } 4077 } else { 4078 Var->setInvalidDecl(); 4079 } 4080 } 4081 4082 // The variable can not have an abstract class type. 4083 if (RequireNonAbstractType(Var->getLocation(), Type, 4084 diag::err_abstract_type_in_decl, 4085 AbstractVariableType)) 4086 Var->setInvalidDecl(); 4087 } 4088 4089#if 0 4090 // FIXME: Temporarily disabled because we are not properly parsing 4091 // linkage specifications on declarations, e.g., 4092 // 4093 // extern "C" const CGPoint CGPointerZero; 4094 // 4095 // C++ [dcl.init]p9: 4096 // 4097 // If no initializer is specified for an object, and the 4098 // object is of (possibly cv-qualified) non-POD class type (or 4099 // array thereof), the object shall be default-initialized; if 4100 // the object is of const-qualified type, the underlying class 4101 // type shall have a user-declared default 4102 // constructor. Otherwise, if no initializer is specified for 4103 // an object, the object and its subobjects, if any, have an 4104 // indeterminate initial value; if the object or any of its 4105 // subobjects are of const-qualified type, the program is 4106 // ill-formed. 4107 // 4108 // This isn't technically an error in C, so we don't diagnose it. 4109 // 4110 // FIXME: Actually perform the POD/user-defined default 4111 // constructor check. 4112 if (getLangOptions().CPlusPlus && 4113 Context.getCanonicalType(Type).isConstQualified() && 4114 !Var->hasExternalStorage()) 4115 Diag(Var->getLocation(), diag::err_const_var_requires_init) 4116 << Var->getName() 4117 << SourceRange(Var->getLocation(), Var->getLocation()); 4118#endif 4119 } 4120} 4121 4122Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4123 DeclPtrTy *Group, 4124 unsigned NumDecls) { 4125 llvm::SmallVector<Decl*, 8> Decls; 4126 4127 if (DS.isTypeSpecOwned()) 4128 Decls.push_back((Decl*)DS.getTypeRep()); 4129 4130 for (unsigned i = 0; i != NumDecls; ++i) 4131 if (Decl *D = Group[i].getAs<Decl>()) 4132 Decls.push_back(D); 4133 4134 // Perform semantic analysis that depends on having fully processed both 4135 // the declarator and initializer. 4136 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 4137 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 4138 if (!IDecl) 4139 continue; 4140 QualType T = IDecl->getType(); 4141 4142 // Block scope. C99 6.7p7: If an identifier for an object is declared with 4143 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 4144 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 4145 if (T->isDependentType()) { 4146 // If T is dependent, we should not require a complete type. 4147 // (RequireCompleteType shouldn't be called with dependent types.) 4148 // But we still can at least check if we've got an array of unspecified 4149 // size without an initializer. 4150 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 4151 !IDecl->getInit()) { 4152 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 4153 << T; 4154 IDecl->setInvalidDecl(); 4155 } 4156 } else if (!IDecl->isInvalidDecl()) { 4157 // If T is an incomplete array type with an initializer list that is 4158 // dependent on something, its size has not been fixed. We could attempt 4159 // to fix the size for such arrays, but we would still have to check 4160 // here for initializers containing a C++0x vararg expansion, e.g. 4161 // template <typename... Args> void f(Args... args) { 4162 // int vals[] = { args }; 4163 // } 4164 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 4165 Expr *Init = IDecl->getInit(); 4166 if (IAT && Init && 4167 (Init->isTypeDependent() || Init->isValueDependent())) { 4168 // Check that the member type of the array is complete, at least. 4169 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 4170 diag::err_typecheck_decl_incomplete_type)) 4171 IDecl->setInvalidDecl(); 4172 } else if (RequireCompleteType(IDecl->getLocation(), T, 4173 diag::err_typecheck_decl_incomplete_type)) 4174 IDecl->setInvalidDecl(); 4175 } 4176 } 4177 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4178 // object that has file scope without an initializer, and without a 4179 // storage-class specifier or with the storage-class specifier "static", 4180 // constitutes a tentative definition. Note: A tentative definition with 4181 // external linkage is valid (C99 6.2.2p5). 4182 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 4183 if (const IncompleteArrayType *ArrayT 4184 = Context.getAsIncompleteArrayType(T)) { 4185 if (RequireCompleteType(IDecl->getLocation(), 4186 ArrayT->getElementType(), 4187 diag::err_illegal_decl_array_incomplete_type)) 4188 IDecl->setInvalidDecl(); 4189 } else if (IDecl->getStorageClass() == VarDecl::Static) { 4190 // C99 6.9.2p3: If the declaration of an identifier for an object is 4191 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4192 // declared type shall not be an incomplete type. 4193 // NOTE: code such as the following 4194 // static struct s; 4195 // struct s { int a; }; 4196 // is accepted by gcc. Hence here we issue a warning instead of 4197 // an error and we do not invalidate the static declaration. 4198 // NOTE: to avoid multiple warnings, only check the first declaration. 4199 if (IDecl->getPreviousDeclaration() == 0) 4200 RequireCompleteType(IDecl->getLocation(), T, 4201 diag::ext_typecheck_decl_incomplete_type); 4202 } 4203 } 4204 } 4205 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4206 Decls.data(), Decls.size())); 4207} 4208 4209 4210/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4211/// to introduce parameters into function prototype scope. 4212Sema::DeclPtrTy 4213Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4214 const DeclSpec &DS = D.getDeclSpec(); 4215 4216 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4217 VarDecl::StorageClass StorageClass = VarDecl::None; 4218 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4219 StorageClass = VarDecl::Register; 4220 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4221 Diag(DS.getStorageClassSpecLoc(), 4222 diag::err_invalid_storage_class_in_func_decl); 4223 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4224 } 4225 4226 if (D.getDeclSpec().isThreadSpecified()) 4227 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4228 4229 DiagnoseFunctionSpecifiers(D); 4230 4231 // Check that there are no default arguments inside the type of this 4232 // parameter (C++ only). 4233 if (getLangOptions().CPlusPlus) 4234 CheckExtraCXXDefaultArguments(D); 4235 4236 TypeSourceInfo *TInfo = 0; 4237 TagDecl *OwnedDecl = 0; 4238 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4239 4240 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4241 // C++ [dcl.fct]p6: 4242 // Types shall not be defined in return or parameter types. 4243 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4244 << Context.getTypeDeclType(OwnedDecl); 4245 } 4246 4247 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 4248 // Can this happen for params? We already checked that they don't conflict 4249 // among each other. Here they can only shadow globals, which is ok. 4250 IdentifierInfo *II = D.getIdentifier(); 4251 if (II) { 4252 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 4253 if (PrevDecl->isTemplateParameter()) { 4254 // Maybe we will complain about the shadowed template parameter. 4255 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4256 // Just pretend that we didn't see the previous declaration. 4257 PrevDecl = 0; 4258 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4259 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4260 4261 // Recover by removing the name 4262 II = 0; 4263 D.SetIdentifier(0, D.getIdentifierLoc()); 4264 } 4265 } 4266 } 4267 4268 // Parameters can not be abstract class types. 4269 // For record types, this is done by the AbstractClassUsageDiagnoser once 4270 // the class has been completely parsed. 4271 if (!CurContext->isRecord() && 4272 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4273 diag::err_abstract_type_in_decl, 4274 AbstractParamType)) 4275 D.setInvalidType(true); 4276 4277 QualType T = adjustParameterType(parmDeclType); 4278 4279 ParmVarDecl *New 4280 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 4281 T, TInfo, StorageClass, 0); 4282 4283 if (D.isInvalidType()) 4284 New->setInvalidDecl(); 4285 4286 // Parameter declarators cannot be interface types. All ObjC objects are 4287 // passed by reference. 4288 if (T->isObjCInterfaceType()) { 4289 Diag(D.getIdentifierLoc(), 4290 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4291 New->setInvalidDecl(); 4292 } 4293 4294 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4295 if (D.getCXXScopeSpec().isSet()) { 4296 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4297 << D.getCXXScopeSpec().getRange(); 4298 New->setInvalidDecl(); 4299 } 4300 4301 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4302 // duration shall not be qualified by an address-space qualifier." 4303 // Since all parameters have automatic store duration, they can not have 4304 // an address space. 4305 if (T.getAddressSpace() != 0) { 4306 Diag(D.getIdentifierLoc(), 4307 diag::err_arg_with_address_space); 4308 New->setInvalidDecl(); 4309 } 4310 4311 4312 // Add the parameter declaration into this scope. 4313 S->AddDecl(DeclPtrTy::make(New)); 4314 if (II) 4315 IdResolver.AddDecl(New); 4316 4317 ProcessDeclAttributes(S, New, D); 4318 4319 if (New->hasAttr<BlocksAttr>()) { 4320 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4321 } 4322 return DeclPtrTy::make(New); 4323} 4324 4325void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4326 SourceLocation LocAfterDecls) { 4327 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4328 "Not a function declarator!"); 4329 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4330 4331 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4332 // for a K&R function. 4333 if (!FTI.hasPrototype) { 4334 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4335 --i; 4336 if (FTI.ArgInfo[i].Param == 0) { 4337 llvm::SmallString<256> Code; 4338 llvm::raw_svector_ostream(Code) << " int " 4339 << FTI.ArgInfo[i].Ident->getName() 4340 << ";\n"; 4341 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4342 << FTI.ArgInfo[i].Ident 4343 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4344 4345 // Implicitly declare the argument as type 'int' for lack of a better 4346 // type. 4347 DeclSpec DS; 4348 const char* PrevSpec; // unused 4349 unsigned DiagID; // unused 4350 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4351 PrevSpec, DiagID); 4352 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4353 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4354 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4355 } 4356 } 4357 } 4358} 4359 4360Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4361 Declarator &D) { 4362 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4363 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4364 "Not a function declarator!"); 4365 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4366 4367 if (FTI.hasPrototype) { 4368 // FIXME: Diagnose arguments without names in C. 4369 } 4370 4371 Scope *ParentScope = FnBodyScope->getParent(); 4372 4373 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4374 MultiTemplateParamsArg(*this), 4375 /*IsFunctionDefinition=*/true); 4376 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4377} 4378 4379static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4380 // Don't warn about invalid declarations. 4381 if (FD->isInvalidDecl()) 4382 return false; 4383 4384 // Or declarations that aren't global. 4385 if (!FD->isGlobal()) 4386 return false; 4387 4388 // Don't warn about C++ member functions. 4389 if (isa<CXXMethodDecl>(FD)) 4390 return false; 4391 4392 // Don't warn about 'main'. 4393 if (FD->isMain()) 4394 return false; 4395 4396 // Don't warn about inline functions. 4397 if (FD->isInlineSpecified()) 4398 return false; 4399 4400 // Don't warn about function templates. 4401 if (FD->getDescribedFunctionTemplate()) 4402 return false; 4403 4404 // Don't warn about function template specializations. 4405 if (FD->isFunctionTemplateSpecialization()) 4406 return false; 4407 4408 bool MissingPrototype = true; 4409 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4410 Prev; Prev = Prev->getPreviousDeclaration()) { 4411 // Ignore any declarations that occur in function or method 4412 // scope, because they aren't visible from the header. 4413 if (Prev->getDeclContext()->isFunctionOrMethod()) 4414 continue; 4415 4416 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4417 break; 4418 } 4419 4420 return MissingPrototype; 4421} 4422 4423Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4424 // Clear the last template instantiation error context. 4425 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4426 4427 if (!D) 4428 return D; 4429 FunctionDecl *FD = 0; 4430 4431 if (FunctionTemplateDecl *FunTmpl 4432 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4433 FD = FunTmpl->getTemplatedDecl(); 4434 else 4435 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4436 4437 CurFunctionNeedsScopeChecking = false; 4438 4439 // See if this is a redefinition. 4440 const FunctionDecl *Definition; 4441 if (FD->getBody(Definition)) { 4442 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4443 Diag(Definition->getLocation(), diag::note_previous_definition); 4444 } 4445 4446 // Builtin functions cannot be defined. 4447 if (unsigned BuiltinID = FD->getBuiltinID()) { 4448 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4449 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4450 FD->setInvalidDecl(); 4451 } 4452 } 4453 4454 // The return type of a function definition must be complete 4455 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4456 QualType ResultType = FD->getResultType(); 4457 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4458 !FD->isInvalidDecl() && 4459 RequireCompleteType(FD->getLocation(), ResultType, 4460 diag::err_func_def_incomplete_result)) 4461 FD->setInvalidDecl(); 4462 4463 // GNU warning -Wmissing-prototypes: 4464 // Warn if a global function is defined without a previous 4465 // prototype declaration. This warning is issued even if the 4466 // definition itself provides a prototype. The aim is to detect 4467 // global functions that fail to be declared in header files. 4468 if (ShouldWarnAboutMissingPrototype(FD)) 4469 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4470 4471 if (FnBodyScope) 4472 PushDeclContext(FnBodyScope, FD); 4473 4474 // Check the validity of our function parameters 4475 CheckParmsForFunctionDef(FD); 4476 4477 // Introduce our parameters into the function scope 4478 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4479 ParmVarDecl *Param = FD->getParamDecl(p); 4480 Param->setOwningFunction(FD); 4481 4482 // If this has an identifier, add it to the scope stack. 4483 if (Param->getIdentifier() && FnBodyScope) 4484 PushOnScopeChains(Param, FnBodyScope); 4485 } 4486 4487 // Checking attributes of current function definition 4488 // dllimport attribute. 4489 if (FD->getAttr<DLLImportAttr>() && 4490 (!FD->getAttr<DLLExportAttr>())) { 4491 // dllimport attribute cannot be applied to definition. 4492 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4493 Diag(FD->getLocation(), 4494 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4495 << "dllimport"; 4496 FD->setInvalidDecl(); 4497 return DeclPtrTy::make(FD); 4498 } else { 4499 // If a symbol previously declared dllimport is later defined, the 4500 // attribute is ignored in subsequent references, and a warning is 4501 // emitted. 4502 Diag(FD->getLocation(), 4503 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4504 << FD->getNameAsCString() << "dllimport"; 4505 } 4506 } 4507 return DeclPtrTy::make(FD); 4508} 4509 4510Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4511 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4512} 4513 4514Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4515 bool IsInstantiation) { 4516 Decl *dcl = D.getAs<Decl>(); 4517 Stmt *Body = BodyArg.takeAs<Stmt>(); 4518 4519 AnalysisContext AC(dcl); 4520 FunctionDecl *FD = 0; 4521 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4522 if (FunTmpl) 4523 FD = FunTmpl->getTemplatedDecl(); 4524 else 4525 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4526 4527 if (FD) { 4528 FD->setBody(Body); 4529 if (FD->isMain()) 4530 // C and C++ allow for main to automagically return 0. 4531 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4532 FD->setHasImplicitReturnZero(true); 4533 else 4534 CheckFallThroughForFunctionDef(FD, Body, AC); 4535 4536 if (!FD->isInvalidDecl()) 4537 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4538 4539 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4540 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4541 4542 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4543 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4544 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4545 MD->setBody(Body); 4546 CheckFallThroughForFunctionDef(MD, Body, AC); 4547 MD->setEndLoc(Body->getLocEnd()); 4548 4549 if (!MD->isInvalidDecl()) 4550 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4551 } else { 4552 Body->Destroy(Context); 4553 return DeclPtrTy(); 4554 } 4555 if (!IsInstantiation) 4556 PopDeclContext(); 4557 4558 // Verify and clean out per-function state. 4559 4560 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4561 4562 // Check goto/label use. 4563 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4564 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4565 LabelStmt *L = I->second; 4566 4567 // Verify that we have no forward references left. If so, there was a goto 4568 // or address of a label taken, but no definition of it. Label fwd 4569 // definitions are indicated with a null substmt. 4570 if (L->getSubStmt() != 0) 4571 continue; 4572 4573 // Emit error. 4574 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4575 4576 // At this point, we have gotos that use the bogus label. Stitch it into 4577 // the function body so that they aren't leaked and that the AST is well 4578 // formed. 4579 if (Body == 0) { 4580 // The whole function wasn't parsed correctly, just delete this. 4581 L->Destroy(Context); 4582 continue; 4583 } 4584 4585 // Otherwise, the body is valid: we want to stitch the label decl into the 4586 // function somewhere so that it is properly owned and so that the goto 4587 // has a valid target. Do this by creating a new compound stmt with the 4588 // label in it. 4589 4590 // Give the label a sub-statement. 4591 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4592 4593 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4594 cast<CXXTryStmt>(Body)->getTryBlock() : 4595 cast<CompoundStmt>(Body); 4596 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4597 Elements.push_back(L); 4598 Compound->setStmts(Context, &Elements[0], Elements.size()); 4599 } 4600 FunctionLabelMap.clear(); 4601 4602 if (!Body) return D; 4603 4604 CheckUnreachable(AC); 4605 4606 // Verify that that gotos and switch cases don't jump into scopes illegally. 4607 if (CurFunctionNeedsScopeChecking) 4608 DiagnoseInvalidJumps(Body); 4609 4610 // C++ constructors that have function-try-blocks can't have return 4611 // statements in the handlers of that block. (C++ [except.handle]p14) 4612 // Verify this. 4613 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4614 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4615 4616 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4617 MarkBaseAndMemberDestructorsReferenced(Destructor); 4618 4619 // If any errors have occurred, clear out any temporaries that may have 4620 // been leftover. This ensures that these temporaries won't be picked up for 4621 // deletion in some later function. 4622 if (PP.getDiagnostics().hasErrorOccurred()) 4623 ExprTemporaries.clear(); 4624 4625 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4626 return D; 4627} 4628 4629/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4630/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4631NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4632 IdentifierInfo &II, Scope *S) { 4633 // Before we produce a declaration for an implicitly defined 4634 // function, see whether there was a locally-scoped declaration of 4635 // this name as a function or variable. If so, use that 4636 // (non-visible) declaration, and complain about it. 4637 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4638 = LocallyScopedExternalDecls.find(&II); 4639 if (Pos != LocallyScopedExternalDecls.end()) { 4640 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4641 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4642 return Pos->second; 4643 } 4644 4645 // Extension in C99. Legal in C90, but warn about it. 4646 if (II.getName().startswith("__builtin_")) 4647 Diag(Loc, diag::warn_builtin_unknown) << &II; 4648 else if (getLangOptions().C99) 4649 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4650 else 4651 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4652 4653 // Set a Declarator for the implicit definition: int foo(); 4654 const char *Dummy; 4655 DeclSpec DS; 4656 unsigned DiagID; 4657 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4658 Error = Error; // Silence warning. 4659 assert(!Error && "Error setting up implicit decl!"); 4660 Declarator D(DS, Declarator::BlockContext); 4661 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4662 0, 0, false, SourceLocation(), 4663 false, 0,0,0, Loc, Loc, D), 4664 SourceLocation()); 4665 D.SetIdentifier(&II, Loc); 4666 4667 // Insert this function into translation-unit scope. 4668 4669 DeclContext *PrevDC = CurContext; 4670 CurContext = Context.getTranslationUnitDecl(); 4671 4672 FunctionDecl *FD = 4673 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4674 FD->setImplicit(); 4675 4676 CurContext = PrevDC; 4677 4678 AddKnownFunctionAttributes(FD); 4679 4680 return FD; 4681} 4682 4683/// \brief Adds any function attributes that we know a priori based on 4684/// the declaration of this function. 4685/// 4686/// These attributes can apply both to implicitly-declared builtins 4687/// (like __builtin___printf_chk) or to library-declared functions 4688/// like NSLog or printf. 4689void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4690 if (FD->isInvalidDecl()) 4691 return; 4692 4693 // If this is a built-in function, map its builtin attributes to 4694 // actual attributes. 4695 if (unsigned BuiltinID = FD->getBuiltinID()) { 4696 // Handle printf-formatting attributes. 4697 unsigned FormatIdx; 4698 bool HasVAListArg; 4699 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4700 if (!FD->getAttr<FormatAttr>()) 4701 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4702 HasVAListArg ? 0 : FormatIdx + 2)); 4703 } 4704 4705 // Mark const if we don't care about errno and that is the only 4706 // thing preventing the function from being const. This allows 4707 // IRgen to use LLVM intrinsics for such functions. 4708 if (!getLangOptions().MathErrno && 4709 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4710 if (!FD->getAttr<ConstAttr>()) 4711 FD->addAttr(::new (Context) ConstAttr()); 4712 } 4713 4714 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4715 FD->addAttr(::new (Context) NoReturnAttr()); 4716 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4717 FD->addAttr(::new (Context) NoThrowAttr()); 4718 if (Context.BuiltinInfo.isConst(BuiltinID)) 4719 FD->addAttr(::new (Context) ConstAttr()); 4720 } 4721 4722 IdentifierInfo *Name = FD->getIdentifier(); 4723 if (!Name) 4724 return; 4725 if ((!getLangOptions().CPlusPlus && 4726 FD->getDeclContext()->isTranslationUnit()) || 4727 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4728 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4729 LinkageSpecDecl::lang_c)) { 4730 // Okay: this could be a libc/libm/Objective-C function we know 4731 // about. 4732 } else 4733 return; 4734 4735 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4736 // FIXME: NSLog and NSLogv should be target specific 4737 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4738 // FIXME: We known better than our headers. 4739 const_cast<FormatAttr *>(Format)->setType("printf"); 4740 } else 4741 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4742 Name->isStr("NSLogv") ? 0 : 2)); 4743 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4744 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4745 // target-specific builtins, perhaps? 4746 if (!FD->getAttr<FormatAttr>()) 4747 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4748 Name->isStr("vasprintf") ? 0 : 3)); 4749 } 4750} 4751 4752TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4753 TypeSourceInfo *TInfo) { 4754 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4755 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4756 4757 if (!TInfo) { 4758 assert(D.isInvalidType() && "no declarator info for valid type"); 4759 TInfo = Context.getTrivialTypeSourceInfo(T); 4760 } 4761 4762 // Scope manipulation handled by caller. 4763 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4764 D.getIdentifierLoc(), 4765 D.getIdentifier(), 4766 TInfo); 4767 4768 if (const TagType *TT = T->getAs<TagType>()) { 4769 TagDecl *TD = TT->getDecl(); 4770 4771 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4772 // keep track of the TypedefDecl. 4773 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4774 TD->setTypedefForAnonDecl(NewTD); 4775 } 4776 4777 if (D.isInvalidType()) 4778 NewTD->setInvalidDecl(); 4779 return NewTD; 4780} 4781 4782 4783/// \brief Determine whether a tag with a given kind is acceptable 4784/// as a redeclaration of the given tag declaration. 4785/// 4786/// \returns true if the new tag kind is acceptable, false otherwise. 4787bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4788 TagDecl::TagKind NewTag, 4789 SourceLocation NewTagLoc, 4790 const IdentifierInfo &Name) { 4791 // C++ [dcl.type.elab]p3: 4792 // The class-key or enum keyword present in the 4793 // elaborated-type-specifier shall agree in kind with the 4794 // declaration to which the name in theelaborated-type-specifier 4795 // refers. This rule also applies to the form of 4796 // elaborated-type-specifier that declares a class-name or 4797 // friend class since it can be construed as referring to the 4798 // definition of the class. Thus, in any 4799 // elaborated-type-specifier, the enum keyword shall be used to 4800 // refer to an enumeration (7.2), the union class-keyshall be 4801 // used to refer to a union (clause 9), and either the class or 4802 // struct class-key shall be used to refer to a class (clause 9) 4803 // declared using the class or struct class-key. 4804 TagDecl::TagKind OldTag = Previous->getTagKind(); 4805 if (OldTag == NewTag) 4806 return true; 4807 4808 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4809 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4810 // Warn about the struct/class tag mismatch. 4811 bool isTemplate = false; 4812 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4813 isTemplate = Record->getDescribedClassTemplate(); 4814 4815 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4816 << (NewTag == TagDecl::TK_class) 4817 << isTemplate << &Name 4818 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4819 OldTag == TagDecl::TK_class? "class" : "struct"); 4820 Diag(Previous->getLocation(), diag::note_previous_use); 4821 return true; 4822 } 4823 return false; 4824} 4825 4826/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4827/// former case, Name will be non-null. In the later case, Name will be null. 4828/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4829/// reference/declaration/definition of a tag. 4830Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4831 SourceLocation KWLoc, const CXXScopeSpec &SS, 4832 IdentifierInfo *Name, SourceLocation NameLoc, 4833 AttributeList *Attr, AccessSpecifier AS, 4834 MultiTemplateParamsArg TemplateParameterLists, 4835 bool &OwnedDecl, bool &IsDependent) { 4836 // If this is not a definition, it must have a name. 4837 assert((Name != 0 || TUK == TUK_Definition) && 4838 "Nameless record must be a definition!"); 4839 4840 OwnedDecl = false; 4841 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4842 4843 // FIXME: Check explicit specializations more carefully. 4844 bool isExplicitSpecialization = false; 4845 if (TUK != TUK_Reference) { 4846 if (TemplateParameterList *TemplateParams 4847 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4848 (TemplateParameterList**)TemplateParameterLists.get(), 4849 TemplateParameterLists.size(), 4850 isExplicitSpecialization)) { 4851 if (TemplateParams->size() > 0) { 4852 // This is a declaration or definition of a class template (which may 4853 // be a member of another template). 4854 OwnedDecl = false; 4855 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4856 SS, Name, NameLoc, Attr, 4857 TemplateParams, 4858 AS); 4859 TemplateParameterLists.release(); 4860 return Result.get(); 4861 } else { 4862 // The "template<>" header is extraneous. 4863 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4864 << ElaboratedType::getNameForTagKind(Kind) << Name; 4865 isExplicitSpecialization = true; 4866 } 4867 } 4868 4869 TemplateParameterLists.release(); 4870 } 4871 4872 DeclContext *SearchDC = CurContext; 4873 DeclContext *DC = CurContext; 4874 bool isStdBadAlloc = false; 4875 bool Invalid = false; 4876 4877 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4878 : NotForRedeclaration); 4879 4880 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4881 4882 if (Name && SS.isNotEmpty()) { 4883 // We have a nested-name tag ('struct foo::bar'). 4884 4885 // Check for invalid 'foo::'. 4886 if (SS.isInvalid()) { 4887 Name = 0; 4888 goto CreateNewDecl; 4889 } 4890 4891 // If this is a friend or a reference to a class in a dependent 4892 // context, don't try to make a decl for it. 4893 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4894 DC = computeDeclContext(SS, false); 4895 if (!DC) { 4896 IsDependent = true; 4897 return DeclPtrTy(); 4898 } 4899 } 4900 4901 if (RequireCompleteDeclContext(SS)) 4902 return DeclPtrTy::make((Decl *)0); 4903 4904 DC = computeDeclContext(SS, true); 4905 SearchDC = DC; 4906 // Look-up name inside 'foo::'. 4907 LookupQualifiedName(Previous, DC); 4908 4909 if (Previous.isAmbiguous()) 4910 return DeclPtrTy(); 4911 4912 if (Previous.empty()) { 4913 // Name lookup did not find anything. However, if the 4914 // nested-name-specifier refers to the current instantiation, 4915 // and that current instantiation has any dependent base 4916 // classes, we might find something at instantiation time: treat 4917 // this as a dependent elaborated-type-specifier. 4918 if (Previous.wasNotFoundInCurrentInstantiation()) { 4919 IsDependent = true; 4920 return DeclPtrTy(); 4921 } 4922 4923 // A tag 'foo::bar' must already exist. 4924 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4925 Name = 0; 4926 Invalid = true; 4927 goto CreateNewDecl; 4928 } 4929 } else if (Name) { 4930 // If this is a named struct, check to see if there was a previous forward 4931 // declaration or definition. 4932 // FIXME: We're looking into outer scopes here, even when we 4933 // shouldn't be. Doing so can result in ambiguities that we 4934 // shouldn't be diagnosing. 4935 LookupName(Previous, S); 4936 4937 // Note: there used to be some attempt at recovery here. 4938 if (Previous.isAmbiguous()) 4939 return DeclPtrTy(); 4940 4941 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4942 // FIXME: This makes sure that we ignore the contexts associated 4943 // with C structs, unions, and enums when looking for a matching 4944 // tag declaration or definition. See the similar lookup tweak 4945 // in Sema::LookupName; is there a better way to deal with this? 4946 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4947 SearchDC = SearchDC->getParent(); 4948 } 4949 } 4950 4951 if (Previous.isSingleResult() && 4952 Previous.getFoundDecl()->isTemplateParameter()) { 4953 // Maybe we will complain about the shadowed template parameter. 4954 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4955 // Just pretend that we didn't see the previous declaration. 4956 Previous.clear(); 4957 } 4958 4959 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4960 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4961 // This is a declaration of or a reference to "std::bad_alloc". 4962 isStdBadAlloc = true; 4963 4964 if (Previous.empty() && StdBadAlloc) { 4965 // std::bad_alloc has been implicitly declared (but made invisible to 4966 // name lookup). Fill in this implicit declaration as the previous 4967 // declaration, so that the declarations get chained appropriately. 4968 Previous.addDecl(StdBadAlloc); 4969 } 4970 } 4971 4972 if (!Previous.empty()) { 4973 assert(Previous.isSingleResult()); 4974 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4975 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4976 // If this is a use of a previous tag, or if the tag is already declared 4977 // in the same scope (so that the definition/declaration completes or 4978 // rementions the tag), reuse the decl. 4979 if (TUK == TUK_Reference || TUK == TUK_Friend || 4980 isDeclInScope(PrevDecl, SearchDC, S)) { 4981 // Make sure that this wasn't declared as an enum and now used as a 4982 // struct or something similar. 4983 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4984 bool SafeToContinue 4985 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4986 Kind != TagDecl::TK_enum); 4987 if (SafeToContinue) 4988 Diag(KWLoc, diag::err_use_with_wrong_tag) 4989 << Name 4990 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4991 PrevTagDecl->getKindName()); 4992 else 4993 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4994 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4995 4996 if (SafeToContinue) 4997 Kind = PrevTagDecl->getTagKind(); 4998 else { 4999 // Recover by making this an anonymous redefinition. 5000 Name = 0; 5001 Previous.clear(); 5002 Invalid = true; 5003 } 5004 } 5005 5006 if (!Invalid) { 5007 // If this is a use, just return the declaration we found. 5008 5009 // FIXME: In the future, return a variant or some other clue 5010 // for the consumer of this Decl to know it doesn't own it. 5011 // For our current ASTs this shouldn't be a problem, but will 5012 // need to be changed with DeclGroups. 5013 if (TUK == TUK_Reference || TUK == TUK_Friend) 5014 return DeclPtrTy::make(PrevTagDecl); 5015 5016 // Diagnose attempts to redefine a tag. 5017 if (TUK == TUK_Definition) { 5018 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 5019 // If we're defining a specialization and the previous definition 5020 // is from an implicit instantiation, don't emit an error 5021 // here; we'll catch this in the general case below. 5022 if (!isExplicitSpecialization || 5023 !isa<CXXRecordDecl>(Def) || 5024 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5025 == TSK_ExplicitSpecialization) { 5026 Diag(NameLoc, diag::err_redefinition) << Name; 5027 Diag(Def->getLocation(), diag::note_previous_definition); 5028 // If this is a redefinition, recover by making this 5029 // struct be anonymous, which will make any later 5030 // references get the previous definition. 5031 Name = 0; 5032 Previous.clear(); 5033 Invalid = true; 5034 } 5035 } else { 5036 // If the type is currently being defined, complain 5037 // about a nested redefinition. 5038 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5039 if (Tag->isBeingDefined()) { 5040 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5041 Diag(PrevTagDecl->getLocation(), 5042 diag::note_previous_definition); 5043 Name = 0; 5044 Previous.clear(); 5045 Invalid = true; 5046 } 5047 } 5048 5049 // Okay, this is definition of a previously declared or referenced 5050 // tag PrevDecl. We're going to create a new Decl for it. 5051 } 5052 } 5053 // If we get here we have (another) forward declaration or we 5054 // have a definition. Just create a new decl. 5055 5056 } else { 5057 // If we get here, this is a definition of a new tag type in a nested 5058 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5059 // new decl/type. We set PrevDecl to NULL so that the entities 5060 // have distinct types. 5061 Previous.clear(); 5062 } 5063 // If we get here, we're going to create a new Decl. If PrevDecl 5064 // is non-NULL, it's a definition of the tag declared by 5065 // PrevDecl. If it's NULL, we have a new definition. 5066 } else { 5067 // PrevDecl is a namespace, template, or anything else 5068 // that lives in the IDNS_Tag identifier namespace. 5069 if (isDeclInScope(PrevDecl, SearchDC, S)) { 5070 // The tag name clashes with a namespace name, issue an error and 5071 // recover by making this tag be anonymous. 5072 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5073 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5074 Name = 0; 5075 Previous.clear(); 5076 Invalid = true; 5077 } else { 5078 // The existing declaration isn't relevant to us; we're in a 5079 // new scope, so clear out the previous declaration. 5080 Previous.clear(); 5081 } 5082 } 5083 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 5084 // C++ [basic.scope.pdecl]p5: 5085 // -- for an elaborated-type-specifier of the form 5086 // 5087 // class-key identifier 5088 // 5089 // if the elaborated-type-specifier is used in the 5090 // decl-specifier-seq or parameter-declaration-clause of a 5091 // function defined in namespace scope, the identifier is 5092 // declared as a class-name in the namespace that contains 5093 // the declaration; otherwise, except as a friend 5094 // declaration, the identifier is declared in the smallest 5095 // non-class, non-function-prototype scope that contains the 5096 // declaration. 5097 // 5098 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5099 // C structs and unions. 5100 // 5101 // It is an error in C++ to declare (rather than define) an enum 5102 // type, including via an elaborated type specifier. We'll 5103 // diagnose that later; for now, declare the enum in the same 5104 // scope as we would have picked for any other tag type. 5105 // 5106 // GNU C also supports this behavior as part of its incomplete 5107 // enum types extension, while GNU C++ does not. 5108 // 5109 // Find the context where we'll be declaring the tag. 5110 // FIXME: We would like to maintain the current DeclContext as the 5111 // lexical context, 5112 while (SearchDC->isRecord()) 5113 SearchDC = SearchDC->getParent(); 5114 5115 // Find the scope where we'll be declaring the tag. 5116 while (S->isClassScope() || 5117 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 5118 ((S->getFlags() & Scope::DeclScope) == 0) || 5119 (S->getEntity() && 5120 ((DeclContext *)S->getEntity())->isTransparentContext())) 5121 S = S->getParent(); 5122 5123 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 5124 // C++ [namespace.memdef]p3: 5125 // If a friend declaration in a non-local class first declares a 5126 // class or function, the friend class or function is a member of 5127 // the innermost enclosing namespace. 5128 while (!SearchDC->isFileContext()) 5129 SearchDC = SearchDC->getParent(); 5130 5131 // The entity of a decl scope is a DeclContext; see PushDeclContext. 5132 while (S->getEntity() != SearchDC) 5133 S = S->getParent(); 5134 } 5135 5136CreateNewDecl: 5137 5138 TagDecl *PrevDecl = 0; 5139 if (Previous.isSingleResult()) 5140 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5141 5142 // If there is an identifier, use the location of the identifier as the 5143 // location of the decl, otherwise use the location of the struct/union 5144 // keyword. 5145 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5146 5147 // Otherwise, create a new declaration. If there is a previous 5148 // declaration of the same entity, the two will be linked via 5149 // PrevDecl. 5150 TagDecl *New; 5151 5152 if (Kind == TagDecl::TK_enum) { 5153 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5154 // enum X { A, B, C } D; D should chain to X. 5155 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5156 cast_or_null<EnumDecl>(PrevDecl)); 5157 // If this is an undefined enum, warn. 5158 if (TUK != TUK_Definition && !Invalid) { 5159 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5160 : diag::ext_forward_ref_enum; 5161 Diag(Loc, DK); 5162 } 5163 } else { 5164 // struct/union/class 5165 5166 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5167 // struct X { int A; } D; D should chain to X. 5168 if (getLangOptions().CPlusPlus) { 5169 // FIXME: Look for a way to use RecordDecl for simple structs. 5170 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5171 cast_or_null<CXXRecordDecl>(PrevDecl)); 5172 5173 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5174 StdBadAlloc = cast<CXXRecordDecl>(New); 5175 } else 5176 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5177 cast_or_null<RecordDecl>(PrevDecl)); 5178 } 5179 5180 if (Kind != TagDecl::TK_enum) { 5181 // Handle #pragma pack: if the #pragma pack stack has non-default 5182 // alignment, make up a packed attribute for this decl. These 5183 // attributes are checked when the ASTContext lays out the 5184 // structure. 5185 // 5186 // It is important for implementing the correct semantics that this 5187 // happen here (in act on tag decl). The #pragma pack stack is 5188 // maintained as a result of parser callbacks which can occur at 5189 // many points during the parsing of a struct declaration (because 5190 // the #pragma tokens are effectively skipped over during the 5191 // parsing of the struct). 5192 if (unsigned Alignment = getPragmaPackAlignment()) 5193 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5194 } 5195 5196 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5197 // C++ [dcl.typedef]p3: 5198 // [...] Similarly, in a given scope, a class or enumeration 5199 // shall not be declared with the same name as a typedef-name 5200 // that is declared in that scope and refers to a type other 5201 // than the class or enumeration itself. 5202 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5203 ForRedeclaration); 5204 LookupName(Lookup, S); 5205 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5206 NamedDecl *PrevTypedefNamed = PrevTypedef; 5207 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5208 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5209 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5210 Diag(Loc, diag::err_tag_definition_of_typedef) 5211 << Context.getTypeDeclType(New) 5212 << PrevTypedef->getUnderlyingType(); 5213 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5214 Invalid = true; 5215 } 5216 } 5217 5218 // If this is a specialization of a member class (of a class template), 5219 // check the specialization. 5220 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5221 Invalid = true; 5222 5223 if (Invalid) 5224 New->setInvalidDecl(); 5225 5226 if (Attr) 5227 ProcessDeclAttributeList(S, New, Attr); 5228 5229 // If we're declaring or defining a tag in function prototype scope 5230 // in C, note that this type can only be used within the function. 5231 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5232 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5233 5234 // Set the lexical context. If the tag has a C++ scope specifier, the 5235 // lexical context will be different from the semantic context. 5236 New->setLexicalDeclContext(CurContext); 5237 5238 // Mark this as a friend decl if applicable. 5239 if (TUK == TUK_Friend) 5240 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5241 5242 // Set the access specifier. 5243 if (!Invalid && TUK != TUK_Friend) 5244 SetMemberAccessSpecifier(New, PrevDecl, AS); 5245 5246 if (TUK == TUK_Definition) 5247 New->startDefinition(); 5248 5249 // If this has an identifier, add it to the scope stack. 5250 if (TUK == TUK_Friend) { 5251 // We might be replacing an existing declaration in the lookup tables; 5252 // if so, borrow its access specifier. 5253 if (PrevDecl) 5254 New->setAccess(PrevDecl->getAccess()); 5255 5256 // Friend tag decls are visible in fairly strange ways. 5257 if (!CurContext->isDependentContext()) { 5258 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5259 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5260 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5261 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5262 } 5263 } else if (Name) { 5264 S = getNonFieldDeclScope(S); 5265 PushOnScopeChains(New, S); 5266 } else { 5267 CurContext->addDecl(New); 5268 } 5269 5270 // If this is the C FILE type, notify the AST context. 5271 if (IdentifierInfo *II = New->getIdentifier()) 5272 if (!New->isInvalidDecl() && 5273 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5274 II->isStr("FILE")) 5275 Context.setFILEDecl(New); 5276 5277 OwnedDecl = true; 5278 return DeclPtrTy::make(New); 5279} 5280 5281void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5282 AdjustDeclIfTemplate(TagD); 5283 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5284 5285 // Enter the tag context. 5286 PushDeclContext(S, Tag); 5287} 5288 5289void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5290 SourceLocation LBraceLoc) { 5291 AdjustDeclIfTemplate(TagD); 5292 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5293 5294 FieldCollector->StartClass(); 5295 5296 if (!Record->getIdentifier()) 5297 return; 5298 5299 // C++ [class]p2: 5300 // [...] The class-name is also inserted into the scope of the 5301 // class itself; this is known as the injected-class-name. For 5302 // purposes of access checking, the injected-class-name is treated 5303 // as if it were a public member name. 5304 CXXRecordDecl *InjectedClassName 5305 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5306 CurContext, Record->getLocation(), 5307 Record->getIdentifier(), 5308 Record->getTagKeywordLoc(), 5309 Record); 5310 InjectedClassName->setImplicit(); 5311 InjectedClassName->setAccess(AS_public); 5312 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5313 InjectedClassName->setDescribedClassTemplate(Template); 5314 PushOnScopeChains(InjectedClassName, S); 5315 assert(InjectedClassName->isInjectedClassName() && 5316 "Broken injected-class-name"); 5317} 5318 5319// Traverses the class and any nested classes, making a note of any 5320// dynamic classes that have no key function so that we can mark all of 5321// their virtual member functions as "used" at the end of the translation 5322// unit. This ensures that all functions needed by the vtable will get 5323// instantiated/synthesized. 5324static void 5325RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5326 SourceLocation Loc) { 5327 // We don't look at dependent or undefined classes. 5328 if (Record->isDependentContext() || !Record->isDefinition()) 5329 return; 5330 5331 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 5332 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 5333 5334 for (DeclContext::decl_iterator D = Record->decls_begin(), 5335 DEnd = Record->decls_end(); 5336 D != DEnd; ++D) { 5337 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5338 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5339 } 5340} 5341 5342void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5343 SourceLocation RBraceLoc) { 5344 AdjustDeclIfTemplate(TagD); 5345 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5346 Tag->setRBraceLoc(RBraceLoc); 5347 5348 if (isa<CXXRecordDecl>(Tag)) 5349 FieldCollector->FinishClass(); 5350 5351 // Exit this scope of this tag's definition. 5352 PopDeclContext(); 5353 5354 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 5355 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5356 RBraceLoc); 5357 5358 // Notify the consumer that we've defined a tag. 5359 Consumer.HandleTagDeclDefinition(Tag); 5360} 5361 5362// Note that FieldName may be null for anonymous bitfields. 5363bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5364 QualType FieldTy, const Expr *BitWidth, 5365 bool *ZeroWidth) { 5366 // Default to true; that shouldn't confuse checks for emptiness 5367 if (ZeroWidth) 5368 *ZeroWidth = true; 5369 5370 // C99 6.7.2.1p4 - verify the field type. 5371 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5372 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5373 // Handle incomplete types with specific error. 5374 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5375 return true; 5376 if (FieldName) 5377 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5378 << FieldName << FieldTy << BitWidth->getSourceRange(); 5379 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5380 << FieldTy << BitWidth->getSourceRange(); 5381 } 5382 5383 // If the bit-width is type- or value-dependent, don't try to check 5384 // it now. 5385 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5386 return false; 5387 5388 llvm::APSInt Value; 5389 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5390 return true; 5391 5392 if (Value != 0 && ZeroWidth) 5393 *ZeroWidth = false; 5394 5395 // Zero-width bitfield is ok for anonymous field. 5396 if (Value == 0 && FieldName) 5397 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5398 5399 if (Value.isSigned() && Value.isNegative()) { 5400 if (FieldName) 5401 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5402 << FieldName << Value.toString(10); 5403 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5404 << Value.toString(10); 5405 } 5406 5407 if (!FieldTy->isDependentType()) { 5408 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5409 if (Value.getZExtValue() > TypeSize) { 5410 if (FieldName) 5411 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5412 << FieldName << (unsigned)TypeSize; 5413 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5414 << (unsigned)TypeSize; 5415 } 5416 } 5417 5418 return false; 5419} 5420 5421/// ActOnField - Each field of a struct/union/class is passed into this in order 5422/// to create a FieldDecl object for it. 5423Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5424 SourceLocation DeclStart, 5425 Declarator &D, ExprTy *BitfieldWidth) { 5426 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5427 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5428 AS_public); 5429 return DeclPtrTy::make(Res); 5430} 5431 5432/// HandleField - Analyze a field of a C struct or a C++ data member. 5433/// 5434FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5435 SourceLocation DeclStart, 5436 Declarator &D, Expr *BitWidth, 5437 AccessSpecifier AS) { 5438 IdentifierInfo *II = D.getIdentifier(); 5439 SourceLocation Loc = DeclStart; 5440 if (II) Loc = D.getIdentifierLoc(); 5441 5442 TypeSourceInfo *TInfo = 0; 5443 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5444 if (getLangOptions().CPlusPlus) 5445 CheckExtraCXXDefaultArguments(D); 5446 5447 DiagnoseFunctionSpecifiers(D); 5448 5449 if (D.getDeclSpec().isThreadSpecified()) 5450 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5451 5452 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5453 ForRedeclaration); 5454 5455 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5456 // Maybe we will complain about the shadowed template parameter. 5457 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5458 // Just pretend that we didn't see the previous declaration. 5459 PrevDecl = 0; 5460 } 5461 5462 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5463 PrevDecl = 0; 5464 5465 bool Mutable 5466 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5467 SourceLocation TSSL = D.getSourceRange().getBegin(); 5468 FieldDecl *NewFD 5469 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5470 AS, PrevDecl, &D); 5471 if (NewFD->isInvalidDecl() && PrevDecl) { 5472 // Don't introduce NewFD into scope; there's already something 5473 // with the same name in the same scope. 5474 } else if (II) { 5475 PushOnScopeChains(NewFD, S); 5476 } else 5477 Record->addDecl(NewFD); 5478 5479 return NewFD; 5480} 5481 5482/// \brief Build a new FieldDecl and check its well-formedness. 5483/// 5484/// This routine builds a new FieldDecl given the fields name, type, 5485/// record, etc. \p PrevDecl should refer to any previous declaration 5486/// with the same name and in the same scope as the field to be 5487/// created. 5488/// 5489/// \returns a new FieldDecl. 5490/// 5491/// \todo The Declarator argument is a hack. It will be removed once 5492FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5493 TypeSourceInfo *TInfo, 5494 RecordDecl *Record, SourceLocation Loc, 5495 bool Mutable, Expr *BitWidth, 5496 SourceLocation TSSL, 5497 AccessSpecifier AS, NamedDecl *PrevDecl, 5498 Declarator *D) { 5499 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5500 bool InvalidDecl = false; 5501 if (D) InvalidDecl = D->isInvalidType(); 5502 5503 // If we receive a broken type, recover by assuming 'int' and 5504 // marking this declaration as invalid. 5505 if (T.isNull()) { 5506 InvalidDecl = true; 5507 T = Context.IntTy; 5508 } 5509 5510 QualType EltTy = Context.getBaseElementType(T); 5511 if (!EltTy->isDependentType() && 5512 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5513 InvalidDecl = true; 5514 5515 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5516 // than a variably modified type. 5517 if (!InvalidDecl && T->isVariablyModifiedType()) { 5518 bool SizeIsNegative; 5519 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5520 SizeIsNegative); 5521 if (!FixedTy.isNull()) { 5522 Diag(Loc, diag::warn_illegal_constant_array_size); 5523 T = FixedTy; 5524 } else { 5525 if (SizeIsNegative) 5526 Diag(Loc, diag::err_typecheck_negative_array_size); 5527 else 5528 Diag(Loc, diag::err_typecheck_field_variable_size); 5529 InvalidDecl = true; 5530 } 5531 } 5532 5533 // Fields can not have abstract class types 5534 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5535 diag::err_abstract_type_in_decl, 5536 AbstractFieldType)) 5537 InvalidDecl = true; 5538 5539 bool ZeroWidth = false; 5540 // If this is declared as a bit-field, check the bit-field. 5541 if (!InvalidDecl && BitWidth && 5542 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5543 InvalidDecl = true; 5544 DeleteExpr(BitWidth); 5545 BitWidth = 0; 5546 ZeroWidth = false; 5547 } 5548 5549 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5550 BitWidth, Mutable); 5551 if (InvalidDecl) 5552 NewFD->setInvalidDecl(); 5553 5554 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5555 Diag(Loc, diag::err_duplicate_member) << II; 5556 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5557 NewFD->setInvalidDecl(); 5558 } 5559 5560 if (getLangOptions().CPlusPlus) { 5561 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5562 5563 if (!T->isPODType()) 5564 CXXRecord->setPOD(false); 5565 if (!ZeroWidth) 5566 CXXRecord->setEmpty(false); 5567 5568 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5569 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5570 5571 if (!RDecl->hasTrivialConstructor()) 5572 CXXRecord->setHasTrivialConstructor(false); 5573 if (!RDecl->hasTrivialCopyConstructor()) 5574 CXXRecord->setHasTrivialCopyConstructor(false); 5575 if (!RDecl->hasTrivialCopyAssignment()) 5576 CXXRecord->setHasTrivialCopyAssignment(false); 5577 if (!RDecl->hasTrivialDestructor()) 5578 CXXRecord->setHasTrivialDestructor(false); 5579 5580 // C++ 9.5p1: An object of a class with a non-trivial 5581 // constructor, a non-trivial copy constructor, a non-trivial 5582 // destructor, or a non-trivial copy assignment operator 5583 // cannot be a member of a union, nor can an array of such 5584 // objects. 5585 // TODO: C++0x alters this restriction significantly. 5586 if (Record->isUnion()) { 5587 // We check for copy constructors before constructors 5588 // because otherwise we'll never get complaints about 5589 // copy constructors. 5590 5591 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5592 5593 CXXSpecialMember member; 5594 if (!RDecl->hasTrivialCopyConstructor()) 5595 member = CXXCopyConstructor; 5596 else if (!RDecl->hasTrivialConstructor()) 5597 member = CXXDefaultConstructor; 5598 else if (!RDecl->hasTrivialCopyAssignment()) 5599 member = CXXCopyAssignment; 5600 else if (!RDecl->hasTrivialDestructor()) 5601 member = CXXDestructor; 5602 else 5603 member = invalid; 5604 5605 if (member != invalid) { 5606 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5607 DiagnoseNontrivial(RT, member); 5608 NewFD->setInvalidDecl(); 5609 } 5610 } 5611 } 5612 } 5613 5614 // FIXME: We need to pass in the attributes given an AST 5615 // representation, not a parser representation. 5616 if (D) 5617 // FIXME: What to pass instead of TUScope? 5618 ProcessDeclAttributes(TUScope, NewFD, *D); 5619 5620 if (T.isObjCGCWeak()) 5621 Diag(Loc, diag::warn_attribute_weak_on_field); 5622 5623 NewFD->setAccess(AS); 5624 5625 // C++ [dcl.init.aggr]p1: 5626 // An aggregate is an array or a class (clause 9) with [...] no 5627 // private or protected non-static data members (clause 11). 5628 // A POD must be an aggregate. 5629 if (getLangOptions().CPlusPlus && 5630 (AS == AS_private || AS == AS_protected)) { 5631 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5632 CXXRecord->setAggregate(false); 5633 CXXRecord->setPOD(false); 5634 } 5635 5636 return NewFD; 5637} 5638 5639/// DiagnoseNontrivial - Given that a class has a non-trivial 5640/// special member, figure out why. 5641void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5642 QualType QT(T, 0U); 5643 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5644 5645 // Check whether the member was user-declared. 5646 switch (member) { 5647 case CXXDefaultConstructor: 5648 if (RD->hasUserDeclaredConstructor()) { 5649 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5650 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5651 const FunctionDecl *body = 0; 5652 ci->getBody(body); 5653 if (!body || 5654 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5655 SourceLocation CtorLoc = ci->getLocation(); 5656 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5657 return; 5658 } 5659 } 5660 5661 assert(0 && "found no user-declared constructors"); 5662 return; 5663 } 5664 break; 5665 5666 case CXXCopyConstructor: 5667 if (RD->hasUserDeclaredCopyConstructor()) { 5668 SourceLocation CtorLoc = 5669 RD->getCopyConstructor(Context, 0)->getLocation(); 5670 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5671 return; 5672 } 5673 break; 5674 5675 case CXXCopyAssignment: 5676 if (RD->hasUserDeclaredCopyAssignment()) { 5677 // FIXME: this should use the location of the copy 5678 // assignment, not the type. 5679 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5680 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5681 return; 5682 } 5683 break; 5684 5685 case CXXDestructor: 5686 if (RD->hasUserDeclaredDestructor()) { 5687 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5688 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5689 return; 5690 } 5691 break; 5692 } 5693 5694 typedef CXXRecordDecl::base_class_iterator base_iter; 5695 5696 // Virtual bases and members inhibit trivial copying/construction, 5697 // but not trivial destruction. 5698 if (member != CXXDestructor) { 5699 // Check for virtual bases. vbases includes indirect virtual bases, 5700 // so we just iterate through the direct bases. 5701 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5702 if (bi->isVirtual()) { 5703 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5704 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5705 return; 5706 } 5707 5708 // Check for virtual methods. 5709 typedef CXXRecordDecl::method_iterator meth_iter; 5710 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5711 ++mi) { 5712 if (mi->isVirtual()) { 5713 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5714 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5715 return; 5716 } 5717 } 5718 } 5719 5720 bool (CXXRecordDecl::*hasTrivial)() const; 5721 switch (member) { 5722 case CXXDefaultConstructor: 5723 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5724 case CXXCopyConstructor: 5725 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5726 case CXXCopyAssignment: 5727 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5728 case CXXDestructor: 5729 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5730 default: 5731 assert(0 && "unexpected special member"); return; 5732 } 5733 5734 // Check for nontrivial bases (and recurse). 5735 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5736 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5737 assert(BaseRT && "Don't know how to handle dependent bases"); 5738 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5739 if (!(BaseRecTy->*hasTrivial)()) { 5740 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5741 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5742 DiagnoseNontrivial(BaseRT, member); 5743 return; 5744 } 5745 } 5746 5747 // Check for nontrivial members (and recurse). 5748 typedef RecordDecl::field_iterator field_iter; 5749 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5750 ++fi) { 5751 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5752 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5753 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5754 5755 if (!(EltRD->*hasTrivial)()) { 5756 SourceLocation FLoc = (*fi)->getLocation(); 5757 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5758 DiagnoseNontrivial(EltRT, member); 5759 return; 5760 } 5761 } 5762 } 5763 5764 assert(0 && "found no explanation for non-trivial member"); 5765} 5766 5767/// TranslateIvarVisibility - Translate visibility from a token ID to an 5768/// AST enum value. 5769static ObjCIvarDecl::AccessControl 5770TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5771 switch (ivarVisibility) { 5772 default: assert(0 && "Unknown visitibility kind"); 5773 case tok::objc_private: return ObjCIvarDecl::Private; 5774 case tok::objc_public: return ObjCIvarDecl::Public; 5775 case tok::objc_protected: return ObjCIvarDecl::Protected; 5776 case tok::objc_package: return ObjCIvarDecl::Package; 5777 } 5778} 5779 5780/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5781/// in order to create an IvarDecl object for it. 5782Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5783 SourceLocation DeclStart, 5784 DeclPtrTy IntfDecl, 5785 Declarator &D, ExprTy *BitfieldWidth, 5786 tok::ObjCKeywordKind Visibility) { 5787 5788 IdentifierInfo *II = D.getIdentifier(); 5789 Expr *BitWidth = (Expr*)BitfieldWidth; 5790 SourceLocation Loc = DeclStart; 5791 if (II) Loc = D.getIdentifierLoc(); 5792 5793 // FIXME: Unnamed fields can be handled in various different ways, for 5794 // example, unnamed unions inject all members into the struct namespace! 5795 5796 TypeSourceInfo *TInfo = 0; 5797 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5798 5799 if (BitWidth) { 5800 // 6.7.2.1p3, 6.7.2.1p4 5801 if (VerifyBitField(Loc, II, T, BitWidth)) { 5802 D.setInvalidType(); 5803 DeleteExpr(BitWidth); 5804 BitWidth = 0; 5805 } 5806 } else { 5807 // Not a bitfield. 5808 5809 // validate II. 5810 5811 } 5812 5813 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5814 // than a variably modified type. 5815 if (T->isVariablyModifiedType()) { 5816 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5817 D.setInvalidType(); 5818 } 5819 5820 // Get the visibility (access control) for this ivar. 5821 ObjCIvarDecl::AccessControl ac = 5822 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5823 : ObjCIvarDecl::None; 5824 // Must set ivar's DeclContext to its enclosing interface. 5825 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5826 DeclContext *EnclosingContext; 5827 if (ObjCImplementationDecl *IMPDecl = 5828 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5829 // Case of ivar declared in an implementation. Context is that of its class. 5830 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5831 assert(IDecl && "No class- ActOnIvar"); 5832 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5833 } else 5834 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5835 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5836 5837 // Construct the decl. 5838 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5839 EnclosingContext, Loc, II, T, 5840 TInfo, ac, (Expr *)BitfieldWidth); 5841 5842 if (II) { 5843 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5844 ForRedeclaration); 5845 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5846 && !isa<TagDecl>(PrevDecl)) { 5847 Diag(Loc, diag::err_duplicate_member) << II; 5848 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5849 NewID->setInvalidDecl(); 5850 } 5851 } 5852 5853 // Process attributes attached to the ivar. 5854 ProcessDeclAttributes(S, NewID, D); 5855 5856 if (D.isInvalidType()) 5857 NewID->setInvalidDecl(); 5858 5859 if (II) { 5860 // FIXME: When interfaces are DeclContexts, we'll need to add 5861 // these to the interface. 5862 S->AddDecl(DeclPtrTy::make(NewID)); 5863 IdResolver.AddDecl(NewID); 5864 } 5865 5866 return DeclPtrTy::make(NewID); 5867} 5868 5869void Sema::ActOnFields(Scope* S, 5870 SourceLocation RecLoc, DeclPtrTy RecDecl, 5871 DeclPtrTy *Fields, unsigned NumFields, 5872 SourceLocation LBrac, SourceLocation RBrac, 5873 AttributeList *Attr) { 5874 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5875 assert(EnclosingDecl && "missing record or interface decl"); 5876 5877 // If the decl this is being inserted into is invalid, then it may be a 5878 // redeclaration or some other bogus case. Don't try to add fields to it. 5879 if (EnclosingDecl->isInvalidDecl()) { 5880 // FIXME: Deallocate fields? 5881 return; 5882 } 5883 5884 5885 // Verify that all the fields are okay. 5886 unsigned NumNamedMembers = 0; 5887 llvm::SmallVector<FieldDecl*, 32> RecFields; 5888 5889 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5890 for (unsigned i = 0; i != NumFields; ++i) { 5891 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5892 5893 // Get the type for the field. 5894 Type *FDTy = FD->getType().getTypePtr(); 5895 5896 if (!FD->isAnonymousStructOrUnion()) { 5897 // Remember all fields written by the user. 5898 RecFields.push_back(FD); 5899 } 5900 5901 // If the field is already invalid for some reason, don't emit more 5902 // diagnostics about it. 5903 if (FD->isInvalidDecl()) { 5904 EnclosingDecl->setInvalidDecl(); 5905 continue; 5906 } 5907 5908 // C99 6.7.2.1p2: 5909 // A structure or union shall not contain a member with 5910 // incomplete or function type (hence, a structure shall not 5911 // contain an instance of itself, but may contain a pointer to 5912 // an instance of itself), except that the last member of a 5913 // structure with more than one named member may have incomplete 5914 // array type; such a structure (and any union containing, 5915 // possibly recursively, a member that is such a structure) 5916 // shall not be a member of a structure or an element of an 5917 // array. 5918 if (FDTy->isFunctionType()) { 5919 // Field declared as a function. 5920 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5921 << FD->getDeclName(); 5922 FD->setInvalidDecl(); 5923 EnclosingDecl->setInvalidDecl(); 5924 continue; 5925 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5926 Record && Record->isStruct()) { 5927 // Flexible array member. 5928 if (NumNamedMembers < 1) { 5929 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5930 << FD->getDeclName(); 5931 FD->setInvalidDecl(); 5932 EnclosingDecl->setInvalidDecl(); 5933 continue; 5934 } 5935 // Okay, we have a legal flexible array member at the end of the struct. 5936 if (Record) 5937 Record->setHasFlexibleArrayMember(true); 5938 } else if (!FDTy->isDependentType() && 5939 RequireCompleteType(FD->getLocation(), FD->getType(), 5940 diag::err_field_incomplete)) { 5941 // Incomplete type 5942 FD->setInvalidDecl(); 5943 EnclosingDecl->setInvalidDecl(); 5944 continue; 5945 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5946 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5947 // If this is a member of a union, then entire union becomes "flexible". 5948 if (Record && Record->isUnion()) { 5949 Record->setHasFlexibleArrayMember(true); 5950 } else { 5951 // If this is a struct/class and this is not the last element, reject 5952 // it. Note that GCC supports variable sized arrays in the middle of 5953 // structures. 5954 if (i != NumFields-1) 5955 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5956 << FD->getDeclName() << FD->getType(); 5957 else { 5958 // We support flexible arrays at the end of structs in 5959 // other structs as an extension. 5960 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5961 << FD->getDeclName(); 5962 if (Record) 5963 Record->setHasFlexibleArrayMember(true); 5964 } 5965 } 5966 } 5967 if (Record && FDTTy->getDecl()->hasObjectMember()) 5968 Record->setHasObjectMember(true); 5969 } else if (FDTy->isObjCInterfaceType()) { 5970 /// A field cannot be an Objective-c object 5971 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5972 FD->setInvalidDecl(); 5973 EnclosingDecl->setInvalidDecl(); 5974 continue; 5975 } else if (getLangOptions().ObjC1 && 5976 getLangOptions().getGCMode() != LangOptions::NonGC && 5977 Record && 5978 (FD->getType()->isObjCObjectPointerType() || 5979 FD->getType().isObjCGCStrong())) 5980 Record->setHasObjectMember(true); 5981 // Keep track of the number of named members. 5982 if (FD->getIdentifier()) 5983 ++NumNamedMembers; 5984 } 5985 5986 // Okay, we successfully defined 'Record'. 5987 if (Record) { 5988 Record->completeDefinition(Context); 5989 } else { 5990 ObjCIvarDecl **ClsFields = 5991 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5992 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5993 ID->setIVarList(ClsFields, RecFields.size(), Context); 5994 ID->setLocEnd(RBrac); 5995 // Add ivar's to class's DeclContext. 5996 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5997 ClsFields[i]->setLexicalDeclContext(ID); 5998 ID->addDecl(ClsFields[i]); 5999 } 6000 // Must enforce the rule that ivars in the base classes may not be 6001 // duplicates. 6002 if (ID->getSuperClass()) { 6003 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 6004 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 6005 ObjCIvarDecl* Ivar = (*IVI); 6006 6007 if (IdentifierInfo *II = Ivar->getIdentifier()) { 6008 ObjCIvarDecl* prevIvar = 6009 ID->getSuperClass()->lookupInstanceVariable(II); 6010 if (prevIvar) { 6011 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 6012 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 6013 } 6014 } 6015 } 6016 } 6017 } else if (ObjCImplementationDecl *IMPDecl = 6018 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6019 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6020 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6021 // Ivar declared in @implementation never belongs to the implementation. 6022 // Only it is in implementation's lexical context. 6023 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6024 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6025 } 6026 } 6027 6028 if (Attr) 6029 ProcessDeclAttributeList(S, Record, Attr); 6030} 6031 6032EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6033 EnumConstantDecl *LastEnumConst, 6034 SourceLocation IdLoc, 6035 IdentifierInfo *Id, 6036 ExprArg val) { 6037 Expr *Val = (Expr *)val.get(); 6038 6039 llvm::APSInt EnumVal(32); 6040 QualType EltTy; 6041 if (Val) { 6042 if (Enum->isDependentType()) 6043 EltTy = Context.DependentTy; 6044 else { 6045 // Make sure to promote the operand type to int. 6046 UsualUnaryConversions(Val); 6047 if (Val != val.get()) { 6048 val.release(); 6049 val = Val; 6050 } 6051 6052 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6053 SourceLocation ExpLoc; 6054 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 6055 Val = 0; 6056 } else { 6057 EltTy = Val->getType(); 6058 } 6059 } 6060 } 6061 6062 if (!Val) { 6063 if (Enum->isDependentType()) 6064 EltTy = Context.DependentTy; 6065 else if (LastEnumConst) { 6066 // Assign the last value + 1. 6067 EnumVal = LastEnumConst->getInitVal(); 6068 ++EnumVal; 6069 6070 // Check for overflow on increment. 6071 if (EnumVal < LastEnumConst->getInitVal()) 6072 Diag(IdLoc, diag::warn_enum_value_overflow); 6073 6074 EltTy = LastEnumConst->getType(); 6075 } else { 6076 // First value, set to zero. 6077 EltTy = Context.IntTy; 6078 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 6079 EnumVal.setIsSigned(true); 6080 } 6081 } 6082 6083 assert(!EltTy.isNull() && "Enum constant with NULL type"); 6084 6085 val.release(); 6086 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6087 Val, EnumVal); 6088} 6089 6090 6091Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6092 DeclPtrTy lastEnumConst, 6093 SourceLocation IdLoc, 6094 IdentifierInfo *Id, 6095 SourceLocation EqualLoc, ExprTy *val) { 6096 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6097 EnumConstantDecl *LastEnumConst = 6098 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6099 Expr *Val = static_cast<Expr*>(val); 6100 6101 // The scope passed in may not be a decl scope. Zip up the scope tree until 6102 // we find one that is. 6103 S = getNonFieldDeclScope(S); 6104 6105 // Verify that there isn't already something declared with this name in this 6106 // scope. 6107 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName, 6108 ForRedeclaration); 6109 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6110 // Maybe we will complain about the shadowed template parameter. 6111 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6112 // Just pretend that we didn't see the previous declaration. 6113 PrevDecl = 0; 6114 } 6115 6116 if (PrevDecl) { 6117 // When in C++, we may get a TagDecl with the same name; in this case the 6118 // enum constant will 'hide' the tag. 6119 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6120 "Received TagDecl when not in C++!"); 6121 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6122 if (isa<EnumConstantDecl>(PrevDecl)) 6123 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6124 else 6125 Diag(IdLoc, diag::err_redefinition) << Id; 6126 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6127 if (Val) Val->Destroy(Context); 6128 return DeclPtrTy(); 6129 } 6130 } 6131 6132 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6133 IdLoc, Id, Owned(Val)); 6134 6135 // Register this decl in the current scope stack. 6136 if (New) 6137 PushOnScopeChains(New, S); 6138 6139 return DeclPtrTy::make(New); 6140} 6141 6142void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6143 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6144 DeclPtrTy *Elements, unsigned NumElements, 6145 Scope *S, AttributeList *Attr) { 6146 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6147 QualType EnumType = Context.getTypeDeclType(Enum); 6148 6149 if (Attr) 6150 ProcessDeclAttributeList(S, Enum, Attr); 6151 6152 if (Enum->isDependentType()) { 6153 for (unsigned i = 0; i != NumElements; ++i) { 6154 EnumConstantDecl *ECD = 6155 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6156 if (!ECD) continue; 6157 6158 ECD->setType(EnumType); 6159 } 6160 6161 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 6162 return; 6163 } 6164 6165 // TODO: If the result value doesn't fit in an int, it must be a long or long 6166 // long value. ISO C does not support this, but GCC does as an extension, 6167 // emit a warning. 6168 unsigned IntWidth = Context.Target.getIntWidth(); 6169 unsigned CharWidth = Context.Target.getCharWidth(); 6170 unsigned ShortWidth = Context.Target.getShortWidth(); 6171 6172 // Verify that all the values are okay, compute the size of the values, and 6173 // reverse the list. 6174 unsigned NumNegativeBits = 0; 6175 unsigned NumPositiveBits = 0; 6176 6177 // Keep track of whether all elements have type int. 6178 bool AllElementsInt = true; 6179 6180 for (unsigned i = 0; i != NumElements; ++i) { 6181 EnumConstantDecl *ECD = 6182 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6183 if (!ECD) continue; // Already issued a diagnostic. 6184 6185 // If the enum value doesn't fit in an int, emit an extension warning. 6186 const llvm::APSInt &InitVal = ECD->getInitVal(); 6187 assert(InitVal.getBitWidth() >= IntWidth && 6188 "Should have promoted value to int"); 6189 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 6190 llvm::APSInt V(InitVal); 6191 V.trunc(IntWidth); 6192 V.extend(InitVal.getBitWidth()); 6193 if (V != InitVal) 6194 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 6195 << InitVal.toString(10); 6196 } 6197 6198 // Keep track of the size of positive and negative values. 6199 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6200 NumPositiveBits = std::max(NumPositiveBits, 6201 (unsigned)InitVal.getActiveBits()); 6202 else 6203 NumNegativeBits = std::max(NumNegativeBits, 6204 (unsigned)InitVal.getMinSignedBits()); 6205 6206 // Keep track of whether every enum element has type int (very commmon). 6207 if (AllElementsInt) 6208 AllElementsInt = ECD->getType() == Context.IntTy; 6209 } 6210 6211 // Figure out the type that should be used for this enum. 6212 // FIXME: Support -fshort-enums. 6213 QualType BestType; 6214 unsigned BestWidth; 6215 6216 // C++0x N3000 [conv.prom]p3: 6217 // An rvalue of an unscoped enumeration type whose underlying 6218 // type is not fixed can be converted to an rvalue of the first 6219 // of the following types that can represent all the values of 6220 // the enumeration: int, unsigned int, long int, unsigned long 6221 // int, long long int, or unsigned long long int. 6222 // C99 6.4.4.3p2: 6223 // An identifier declared as an enumeration constant has type int. 6224 // The C99 rule is modified by a gcc extension 6225 QualType BestPromotionType; 6226 6227 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6228 6229 if (NumNegativeBits) { 6230 // If there is a negative value, figure out the smallest integer type (of 6231 // int/long/longlong) that fits. 6232 // If it's packed, check also if it fits a char or a short. 6233 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6234 BestType = Context.SignedCharTy; 6235 BestWidth = CharWidth; 6236 } else if (Packed && NumNegativeBits <= ShortWidth && 6237 NumPositiveBits < ShortWidth) { 6238 BestType = Context.ShortTy; 6239 BestWidth = ShortWidth; 6240 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6241 BestType = Context.IntTy; 6242 BestWidth = IntWidth; 6243 } else { 6244 BestWidth = Context.Target.getLongWidth(); 6245 6246 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6247 BestType = Context.LongTy; 6248 } else { 6249 BestWidth = Context.Target.getLongLongWidth(); 6250 6251 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6252 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6253 BestType = Context.LongLongTy; 6254 } 6255 } 6256 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6257 } else { 6258 // If there is no negative value, figure out which of uint, ulong, ulonglong 6259 // fits. 6260 // If it's packed, check also if it fits a char or a short. 6261 if (Packed && NumPositiveBits <= CharWidth) { 6262 BestType = Context.UnsignedCharTy; 6263 BestPromotionType = Context.IntTy; 6264 BestWidth = CharWidth; 6265 } else if (Packed && NumPositiveBits <= ShortWidth) { 6266 BestType = Context.UnsignedShortTy; 6267 BestPromotionType = Context.IntTy; 6268 BestWidth = ShortWidth; 6269 } else if (NumPositiveBits <= IntWidth) { 6270 BestType = Context.UnsignedIntTy; 6271 BestWidth = IntWidth; 6272 BestPromotionType = (NumPositiveBits == BestWidth 6273 ? Context.UnsignedIntTy : Context.IntTy); 6274 } else if (NumPositiveBits <= 6275 (BestWidth = Context.Target.getLongWidth())) { 6276 BestType = Context.UnsignedLongTy; 6277 BestPromotionType = (NumPositiveBits == BestWidth 6278 ? Context.UnsignedLongTy : Context.LongTy); 6279 } else { 6280 BestWidth = Context.Target.getLongLongWidth(); 6281 assert(NumPositiveBits <= BestWidth && 6282 "How could an initializer get larger than ULL?"); 6283 BestType = Context.UnsignedLongLongTy; 6284 BestPromotionType = (NumPositiveBits == BestWidth 6285 ? Context.UnsignedLongLongTy : Context.LongLongTy); 6286 } 6287 } 6288 6289 // If we're in C and the promotion type is larger than an int, just 6290 // use the underlying type, which is generally the unsigned integer 6291 // type of the same rank as the promotion type. This is how the gcc 6292 // extension works. 6293 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 6294 BestPromotionType = BestType; 6295 6296 // Loop over all of the enumerator constants, changing their types to match 6297 // the type of the enum if needed. 6298 for (unsigned i = 0; i != NumElements; ++i) { 6299 EnumConstantDecl *ECD = 6300 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6301 if (!ECD) continue; // Already issued a diagnostic. 6302 6303 // Standard C says the enumerators have int type, but we allow, as an 6304 // extension, the enumerators to be larger than int size. If each 6305 // enumerator value fits in an int, type it as an int, otherwise type it the 6306 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6307 // that X has type 'int', not 'unsigned'. 6308 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 6309 continue; 6310 6311 // Determine whether the value fits into an int. 6312 llvm::APSInt InitVal = ECD->getInitVal(); 6313 bool FitsInInt; 6314 if (InitVal.isUnsigned() || !InitVal.isNegative()) 6315 FitsInInt = InitVal.getActiveBits() < IntWidth; 6316 else 6317 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 6318 6319 // If it fits into an integer type, force it. Otherwise force it to match 6320 // the enum decl type. 6321 QualType NewTy; 6322 unsigned NewWidth; 6323 bool NewSign; 6324 if (FitsInInt && !getLangOptions().CPlusPlus) { 6325 NewTy = Context.IntTy; 6326 NewWidth = IntWidth; 6327 NewSign = true; 6328 } else if (ECD->getType() == BestType) { 6329 // Already the right type! 6330 if (getLangOptions().CPlusPlus) 6331 // C++ [dcl.enum]p4: Following the closing brace of an 6332 // enum-specifier, each enumerator has the type of its 6333 // enumeration. 6334 ECD->setType(EnumType); 6335 continue; 6336 } else { 6337 NewTy = BestType; 6338 NewWidth = BestWidth; 6339 NewSign = BestType->isSignedIntegerType(); 6340 } 6341 6342 // Adjust the APSInt value. 6343 InitVal.extOrTrunc(NewWidth); 6344 InitVal.setIsSigned(NewSign); 6345 ECD->setInitVal(InitVal); 6346 6347 // Adjust the Expr initializer and type. 6348 if (ECD->getInitExpr()) 6349 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6350 CastExpr::CK_IntegralCast, 6351 ECD->getInitExpr(), 6352 /*isLvalue=*/false)); 6353 if (getLangOptions().CPlusPlus) 6354 // C++ [dcl.enum]p4: Following the closing brace of an 6355 // enum-specifier, each enumerator has the type of its 6356 // enumeration. 6357 ECD->setType(EnumType); 6358 else 6359 ECD->setType(NewTy); 6360 } 6361 6362 Enum->completeDefinition(Context, BestType, BestPromotionType); 6363} 6364 6365Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6366 ExprArg expr) { 6367 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6368 6369 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6370 Loc, AsmString); 6371 CurContext->addDecl(New); 6372 return DeclPtrTy::make(New); 6373} 6374 6375void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6376 SourceLocation PragmaLoc, 6377 SourceLocation NameLoc) { 6378 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6379 6380 if (PrevDecl) { 6381 PrevDecl->addAttr(::new (Context) WeakAttr()); 6382 } else { 6383 (void)WeakUndeclaredIdentifiers.insert( 6384 std::pair<IdentifierInfo*,WeakInfo> 6385 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6386 } 6387} 6388 6389void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6390 IdentifierInfo* AliasName, 6391 SourceLocation PragmaLoc, 6392 SourceLocation NameLoc, 6393 SourceLocation AliasNameLoc) { 6394 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6395 WeakInfo W = WeakInfo(Name, NameLoc); 6396 6397 if (PrevDecl) { 6398 if (!PrevDecl->hasAttr<AliasAttr>()) 6399 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6400 DeclApplyPragmaWeak(TUScope, ND, W); 6401 } else { 6402 (void)WeakUndeclaredIdentifiers.insert( 6403 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6404 } 6405} 6406