SemaDecl.cpp revision 13550e08024d7c6476149f800c01ed0306e403f0
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 BinaryOperator *Op = cast<BinaryOperator>(S); 1343 if (Op->getOpcode() == BinaryOperator::Comma) { 1344 if (b.size() < 2) { 1345 CFGBlock *n = &b; 1346 while (1) { 1347 if (n->getTerminator()) 1348 return n->getTerminator()->getLocStart(); 1349 if (n->succ_size() != 1) 1350 return SourceLocation(); 1351 n = n[0].succ_begin()[0]; 1352 if (n->pred_size() != 1) 1353 return SourceLocation(); 1354 if (!n->empty()) 1355 return n[0][0].getStmt()->getLocStart(); 1356 } 1357 } 1358 return b[1].getStmt()->getLocStart(); 1359 } 1360 } 1361 default: ; 1362 } 1363 return S->getLocStart(); 1364} 1365 1366static SourceLocation MarkLiveTop(CFGBlock *e, llvm::BitVector &live, 1367 SourceManager &SM) { 1368 std::queue<CFGBlock*> workq; 1369 // Prep work queue 1370 workq.push(e); 1371 SourceLocation top = GetUnreachableLoc(*e); 1372 bool FromMainFile = false; 1373 bool FromSystemHeader = false; 1374 bool TopValid = false; 1375 if (top.isValid()) { 1376 FromMainFile = SM.isFromMainFile(top); 1377 FromSystemHeader = SM.isInSystemHeader(top); 1378 TopValid = true; 1379 } 1380 // Solve 1381 while (!workq.empty()) { 1382 CFGBlock *item = workq.front(); 1383 workq.pop(); 1384 SourceLocation c = GetUnreachableLoc(*item); 1385 if (c.isValid() 1386 && (!TopValid 1387 || (SM.isFromMainFile(c) && !FromMainFile) 1388 || (FromSystemHeader && !SM.isInSystemHeader(c)) 1389 || SM.isBeforeInTranslationUnit(c, top))) { 1390 top = c; 1391 FromMainFile = SM.isFromMainFile(top); 1392 FromSystemHeader = SM.isInSystemHeader(top); 1393 } 1394 live.set(item->getBlockID()); 1395 for (CFGBlock::succ_iterator I=item->succ_begin(), 1396 E=item->succ_end(); 1397 I != E; 1398 ++I) { 1399 if ((*I) && !live[(*I)->getBlockID()]) { 1400 live.set((*I)->getBlockID()); 1401 workq.push(*I); 1402 } 1403 } 1404 } 1405 return top; 1406} 1407 1408namespace { 1409class LineCmp { 1410 SourceManager &SM; 1411public: 1412 LineCmp(SourceManager &sm) : SM(sm) { 1413 } 1414 bool operator () (SourceLocation l1, SourceLocation l2) { 1415 return l1 < l2; 1416 } 1417}; 1418} 1419 1420/// CheckUnreachable - Check for unreachable code. 1421void Sema::CheckUnreachable(AnalysisContext &AC) { 1422 // We avoid checking when there are errors, as the CFG won't faithfully match 1423 // the user's code. 1424 if (getDiagnostics().hasErrorOccurred()) 1425 return; 1426 if (Diags.getDiagnosticLevel(diag::warn_unreachable) == Diagnostic::Ignored) 1427 return; 1428 1429 CFG *cfg = AC.getCFG(); 1430 if (cfg == 0) 1431 return; 1432 1433 llvm::BitVector live(cfg->getNumBlockIDs()); 1434 // Mark all live things first. 1435 MarkLive(&cfg->getEntry(), live); 1436 1437 llvm::SmallVector<SourceLocation, 24> lines; 1438 // First, give warnings for blocks with no predecessors, as they 1439 // can't be part of a loop. 1440 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1441 CFGBlock &b = **I; 1442 if (!live[b.getBlockID()]) { 1443 if (b.pred_begin() == b.pred_end()) { 1444 SourceLocation c = GetUnreachableLoc(b); 1445 if (!c.isValid()) { 1446 // Blocks without a location can't produce a warning, so don't mark 1447 // reachable blocks from here as live. 1448 live.set(b.getBlockID()); 1449 continue; 1450 } 1451 lines.push_back(c); 1452 // Avoid excessive errors by marking everything reachable from here 1453 MarkLive(&b, live); 1454 } 1455 } 1456 } 1457 1458 // And then give warnings for the tops of loops. 1459 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1460 CFGBlock &b = **I; 1461 if (!live[b.getBlockID()]) 1462 // Avoid excessive errors by marking everything reachable from here 1463 lines.push_back(MarkLiveTop(&b, live, Context.getSourceManager())); 1464 } 1465 1466 std::sort(lines.begin(), lines.end(), LineCmp(Context.getSourceManager())); 1467 for (llvm::SmallVector<SourceLocation, 24>::iterator I = lines.begin(), 1468 E = lines.end(); 1469 I != E; 1470 ++I) 1471 if (I->isValid()) 1472 Diag(*I, diag::warn_unreachable); 1473} 1474 1475/// CheckFallThrough - Check that we don't fall off the end of a 1476/// Statement that should return a value. 1477/// 1478/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1479/// MaybeFallThrough iff we might or might not fall off the end, 1480/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1481/// return. We assume NeverFallThrough iff we never fall off the end of the 1482/// statement but we may return. We assume that functions not marked noreturn 1483/// will return. 1484Sema::ControlFlowKind Sema::CheckFallThrough(AnalysisContext &AC) { 1485 CFG *cfg = AC.getCFG(); 1486 if (cfg == 0) 1487 // FIXME: This should be NeverFallThrough 1488 return NeverFallThroughOrReturn; 1489 1490 // The CFG leaves in dead things, and we don't want to dead code paths to 1491 // confuse us, so we mark all live things first. 1492 std::queue<CFGBlock*> workq; 1493 llvm::BitVector live(cfg->getNumBlockIDs()); 1494 MarkLive(&cfg->getEntry(), live); 1495 1496 // Now we know what is live, we check the live precessors of the exit block 1497 // and look for fall through paths, being careful to ignore normal returns, 1498 // and exceptional paths. 1499 bool HasLiveReturn = false; 1500 bool HasFakeEdge = false; 1501 bool HasPlainEdge = false; 1502 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1503 E = cfg->getExit().pred_end(); 1504 I != E; 1505 ++I) { 1506 CFGBlock& B = **I; 1507 if (!live[B.getBlockID()]) 1508 continue; 1509 if (B.size() == 0) { 1510 // A labeled empty statement, or the entry block... 1511 HasPlainEdge = true; 1512 continue; 1513 } 1514 Stmt *S = B[B.size()-1]; 1515 if (isa<ReturnStmt>(S)) { 1516 HasLiveReturn = true; 1517 continue; 1518 } 1519 if (isa<ObjCAtThrowStmt>(S)) { 1520 HasFakeEdge = true; 1521 continue; 1522 } 1523 if (isa<CXXThrowExpr>(S)) { 1524 HasFakeEdge = true; 1525 continue; 1526 } 1527 if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) { 1528 if (AS->isMSAsm()) { 1529 HasFakeEdge = true; 1530 HasLiveReturn = true; 1531 continue; 1532 } 1533 } 1534 1535 bool NoReturnEdge = false; 1536 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1537 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1538 if (CEE->getType().getNoReturnAttr()) { 1539 NoReturnEdge = true; 1540 HasFakeEdge = true; 1541 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1542 ValueDecl *VD = DRE->getDecl(); 1543 if (VD->hasAttr<NoReturnAttr>()) { 1544 NoReturnEdge = true; 1545 HasFakeEdge = true; 1546 } 1547 } 1548 } 1549 // FIXME: Add noreturn message sends. 1550 if (NoReturnEdge == false) 1551 HasPlainEdge = true; 1552 } 1553 if (!HasPlainEdge) { 1554 if (HasLiveReturn) 1555 return NeverFallThrough; 1556 return NeverFallThroughOrReturn; 1557 } 1558 if (HasFakeEdge || HasLiveReturn) 1559 return MaybeFallThrough; 1560 // This says AlwaysFallThrough for calls to functions that are not marked 1561 // noreturn, that don't return. If people would like this warning to be more 1562 // accurate, such functions should be marked as noreturn. 1563 return AlwaysFallThrough; 1564} 1565 1566/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1567/// function that should return a value. Check that we don't fall off the end 1568/// of a noreturn function. We assume that functions and blocks not marked 1569/// noreturn will return. 1570void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body, 1571 AnalysisContext &AC) { 1572 // FIXME: Would be nice if we had a better way to control cascading errors, 1573 // but for now, avoid them. The problem is that when Parse sees: 1574 // int foo() { return a; } 1575 // The return is eaten and the Sema code sees just: 1576 // int foo() { } 1577 // which this code would then warn about. 1578 if (getDiagnostics().hasErrorOccurred()) 1579 return; 1580 1581 bool ReturnsVoid = false; 1582 bool HasNoReturn = false; 1583 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1584 // If the result type of the function is a dependent type, we don't know 1585 // whether it will be void or not, so don't 1586 if (FD->getResultType()->isDependentType()) 1587 return; 1588 if (FD->getResultType()->isVoidType()) 1589 ReturnsVoid = true; 1590 if (FD->hasAttr<NoReturnAttr>()) 1591 HasNoReturn = true; 1592 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1593 if (MD->getResultType()->isVoidType()) 1594 ReturnsVoid = true; 1595 if (MD->hasAttr<NoReturnAttr>()) 1596 HasNoReturn = true; 1597 } 1598 1599 // Short circuit for compilation speed. 1600 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1601 == Diagnostic::Ignored || ReturnsVoid) 1602 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1603 == Diagnostic::Ignored || !HasNoReturn) 1604 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1605 == Diagnostic::Ignored || !ReturnsVoid)) 1606 return; 1607 // FIXME: Function try block 1608 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1609 switch (CheckFallThrough(AC)) { 1610 case MaybeFallThrough: 1611 if (HasNoReturn) 1612 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1613 else if (!ReturnsVoid) 1614 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1615 break; 1616 case AlwaysFallThrough: 1617 if (HasNoReturn) 1618 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1619 else if (!ReturnsVoid) 1620 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1621 break; 1622 case NeverFallThroughOrReturn: 1623 if (ReturnsVoid && !HasNoReturn) 1624 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1625 break; 1626 case NeverFallThrough: 1627 break; 1628 } 1629 } 1630} 1631 1632/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1633/// that should return a value. Check that we don't fall off the end of a 1634/// noreturn block. We assume that functions and blocks not marked noreturn 1635/// will return. 1636void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body, 1637 AnalysisContext &AC) { 1638 // FIXME: Would be nice if we had a better way to control cascading errors, 1639 // but for now, avoid them. The problem is that when Parse sees: 1640 // int foo() { return a; } 1641 // The return is eaten and the Sema code sees just: 1642 // int foo() { } 1643 // which this code would then warn about. 1644 if (getDiagnostics().hasErrorOccurred()) 1645 return; 1646 bool ReturnsVoid = false; 1647 bool HasNoReturn = false; 1648 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1649 if (FT->getResultType()->isVoidType()) 1650 ReturnsVoid = true; 1651 if (FT->getNoReturnAttr()) 1652 HasNoReturn = true; 1653 } 1654 1655 // Short circuit for compilation speed. 1656 if (ReturnsVoid 1657 && !HasNoReturn 1658 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1659 == Diagnostic::Ignored || !ReturnsVoid)) 1660 return; 1661 // FIXME: Funtion try block 1662 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1663 switch (CheckFallThrough(AC)) { 1664 case MaybeFallThrough: 1665 if (HasNoReturn) 1666 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1667 else if (!ReturnsVoid) 1668 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1669 break; 1670 case AlwaysFallThrough: 1671 if (HasNoReturn) 1672 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1673 else if (!ReturnsVoid) 1674 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1675 break; 1676 case NeverFallThroughOrReturn: 1677 if (ReturnsVoid) 1678 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1679 break; 1680 case NeverFallThrough: 1681 break; 1682 } 1683 } 1684} 1685 1686/// CheckParmsForFunctionDef - Check that the parameters of the given 1687/// function are appropriate for the definition of a function. This 1688/// takes care of any checks that cannot be performed on the 1689/// declaration itself, e.g., that the types of each of the function 1690/// parameters are complete. 1691bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1692 bool HasInvalidParm = false; 1693 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1694 ParmVarDecl *Param = FD->getParamDecl(p); 1695 1696 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1697 // function declarator that is part of a function definition of 1698 // that function shall not have incomplete type. 1699 // 1700 // This is also C++ [dcl.fct]p6. 1701 if (!Param->isInvalidDecl() && 1702 RequireCompleteType(Param->getLocation(), Param->getType(), 1703 diag::err_typecheck_decl_incomplete_type)) { 1704 Param->setInvalidDecl(); 1705 HasInvalidParm = true; 1706 } 1707 1708 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1709 // declaration of each parameter shall include an identifier. 1710 if (Param->getIdentifier() == 0 && 1711 !Param->isImplicit() && 1712 !getLangOptions().CPlusPlus) 1713 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1714 } 1715 1716 return HasInvalidParm; 1717} 1718 1719/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1720/// no declarator (e.g. "struct foo;") is parsed. 1721Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1722 // FIXME: Error on auto/register at file scope 1723 // FIXME: Error on inline/virtual/explicit 1724 // FIXME: Warn on useless __thread 1725 // FIXME: Warn on useless const/volatile 1726 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1727 // FIXME: Warn on useless attributes 1728 Decl *TagD = 0; 1729 TagDecl *Tag = 0; 1730 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1731 DS.getTypeSpecType() == DeclSpec::TST_struct || 1732 DS.getTypeSpecType() == DeclSpec::TST_union || 1733 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1734 TagD = static_cast<Decl *>(DS.getTypeRep()); 1735 1736 if (!TagD) // We probably had an error 1737 return DeclPtrTy(); 1738 1739 // Note that the above type specs guarantee that the 1740 // type rep is a Decl, whereas in many of the others 1741 // it's a Type. 1742 Tag = dyn_cast<TagDecl>(TagD); 1743 } 1744 1745 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1746 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1747 // or incomplete types shall not be restrict-qualified." 1748 if (TypeQuals & DeclSpec::TQ_restrict) 1749 Diag(DS.getRestrictSpecLoc(), 1750 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1751 << DS.getSourceRange(); 1752 } 1753 1754 if (DS.isFriendSpecified()) { 1755 // If we're dealing with a class template decl, assume that the 1756 // template routines are handling it. 1757 if (TagD && isa<ClassTemplateDecl>(TagD)) 1758 return DeclPtrTy(); 1759 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1760 } 1761 1762 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1763 // If there are attributes in the DeclSpec, apply them to the record. 1764 if (const AttributeList *AL = DS.getAttributes()) 1765 ProcessDeclAttributeList(S, Record, AL); 1766 1767 if (!Record->getDeclName() && Record->isDefinition() && 1768 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1769 if (getLangOptions().CPlusPlus || 1770 Record->getDeclContext()->isRecord()) 1771 return BuildAnonymousStructOrUnion(S, DS, Record); 1772 1773 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1774 << DS.getSourceRange(); 1775 } 1776 1777 // Microsoft allows unnamed struct/union fields. Don't complain 1778 // about them. 1779 // FIXME: Should we support Microsoft's extensions in this area? 1780 if (Record->getDeclName() && getLangOptions().Microsoft) 1781 return DeclPtrTy::make(Tag); 1782 } 1783 1784 if (!DS.isMissingDeclaratorOk() && 1785 DS.getTypeSpecType() != DeclSpec::TST_error) { 1786 // Warn about typedefs of enums without names, since this is an 1787 // extension in both Microsoft an GNU. 1788 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1789 Tag && isa<EnumDecl>(Tag)) { 1790 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1791 << DS.getSourceRange(); 1792 return DeclPtrTy::make(Tag); 1793 } 1794 1795 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1796 << DS.getSourceRange(); 1797 return DeclPtrTy(); 1798 } 1799 1800 return DeclPtrTy::make(Tag); 1801} 1802 1803/// We are trying to inject an anonymous member into the given scope; 1804/// check if there's an existing declaration that can't be overloaded. 1805/// 1806/// \return true if this is a forbidden redeclaration 1807static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1808 Scope *S, 1809 DeclarationName Name, 1810 SourceLocation NameLoc, 1811 unsigned diagnostic) { 1812 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1813 Sema::ForRedeclaration); 1814 if (!SemaRef.LookupName(R, S)) return false; 1815 1816 if (R.getAsSingle<TagDecl>()) 1817 return false; 1818 1819 // Pick a representative declaration. 1820 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1821 1822 SemaRef.Diag(NameLoc, diagnostic) << Name; 1823 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1824 1825 return true; 1826} 1827 1828/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1829/// anonymous struct or union AnonRecord into the owning context Owner 1830/// and scope S. This routine will be invoked just after we realize 1831/// that an unnamed union or struct is actually an anonymous union or 1832/// struct, e.g., 1833/// 1834/// @code 1835/// union { 1836/// int i; 1837/// float f; 1838/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1839/// // f into the surrounding scope.x 1840/// @endcode 1841/// 1842/// This routine is recursive, injecting the names of nested anonymous 1843/// structs/unions into the owning context and scope as well. 1844bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1845 RecordDecl *AnonRecord) { 1846 unsigned diagKind 1847 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1848 : diag::err_anonymous_struct_member_redecl; 1849 1850 bool Invalid = false; 1851 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1852 FEnd = AnonRecord->field_end(); 1853 F != FEnd; ++F) { 1854 if ((*F)->getDeclName()) { 1855 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1856 (*F)->getLocation(), diagKind)) { 1857 // C++ [class.union]p2: 1858 // The names of the members of an anonymous union shall be 1859 // distinct from the names of any other entity in the 1860 // scope in which the anonymous union is declared. 1861 Invalid = true; 1862 } else { 1863 // C++ [class.union]p2: 1864 // For the purpose of name lookup, after the anonymous union 1865 // definition, the members of the anonymous union are 1866 // considered to have been defined in the scope in which the 1867 // anonymous union is declared. 1868 Owner->makeDeclVisibleInContext(*F); 1869 S->AddDecl(DeclPtrTy::make(*F)); 1870 IdResolver.AddDecl(*F); 1871 } 1872 } else if (const RecordType *InnerRecordType 1873 = (*F)->getType()->getAs<RecordType>()) { 1874 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1875 if (InnerRecord->isAnonymousStructOrUnion()) 1876 Invalid = Invalid || 1877 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1878 } 1879 } 1880 1881 return Invalid; 1882} 1883 1884/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1885/// anonymous structure or union. Anonymous unions are a C++ feature 1886/// (C++ [class.union]) and a GNU C extension; anonymous structures 1887/// are a GNU C and GNU C++ extension. 1888Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1889 RecordDecl *Record) { 1890 DeclContext *Owner = Record->getDeclContext(); 1891 1892 // Diagnose whether this anonymous struct/union is an extension. 1893 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1894 Diag(Record->getLocation(), diag::ext_anonymous_union); 1895 else if (!Record->isUnion()) 1896 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1897 1898 // C and C++ require different kinds of checks for anonymous 1899 // structs/unions. 1900 bool Invalid = false; 1901 if (getLangOptions().CPlusPlus) { 1902 const char* PrevSpec = 0; 1903 unsigned DiagID; 1904 // C++ [class.union]p3: 1905 // Anonymous unions declared in a named namespace or in the 1906 // global namespace shall be declared static. 1907 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1908 (isa<TranslationUnitDecl>(Owner) || 1909 (isa<NamespaceDecl>(Owner) && 1910 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1911 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1912 Invalid = true; 1913 1914 // Recover by adding 'static'. 1915 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1916 PrevSpec, DiagID); 1917 } 1918 // C++ [class.union]p3: 1919 // A storage class is not allowed in a declaration of an 1920 // anonymous union in a class scope. 1921 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1922 isa<RecordDecl>(Owner)) { 1923 Diag(DS.getStorageClassSpecLoc(), 1924 diag::err_anonymous_union_with_storage_spec); 1925 Invalid = true; 1926 1927 // Recover by removing the storage specifier. 1928 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1929 PrevSpec, DiagID); 1930 } 1931 1932 // C++ [class.union]p2: 1933 // The member-specification of an anonymous union shall only 1934 // define non-static data members. [Note: nested types and 1935 // functions cannot be declared within an anonymous union. ] 1936 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1937 MemEnd = Record->decls_end(); 1938 Mem != MemEnd; ++Mem) { 1939 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1940 // C++ [class.union]p3: 1941 // An anonymous union shall not have private or protected 1942 // members (clause 11). 1943 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1944 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1945 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1946 Invalid = true; 1947 } 1948 } else if ((*Mem)->isImplicit()) { 1949 // Any implicit members are fine. 1950 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1951 // This is a type that showed up in an 1952 // elaborated-type-specifier inside the anonymous struct or 1953 // union, but which actually declares a type outside of the 1954 // anonymous struct or union. It's okay. 1955 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1956 if (!MemRecord->isAnonymousStructOrUnion() && 1957 MemRecord->getDeclName()) { 1958 // This is a nested type declaration. 1959 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1960 << (int)Record->isUnion(); 1961 Invalid = true; 1962 } 1963 } else { 1964 // We have something that isn't a non-static data 1965 // member. Complain about it. 1966 unsigned DK = diag::err_anonymous_record_bad_member; 1967 if (isa<TypeDecl>(*Mem)) 1968 DK = diag::err_anonymous_record_with_type; 1969 else if (isa<FunctionDecl>(*Mem)) 1970 DK = diag::err_anonymous_record_with_function; 1971 else if (isa<VarDecl>(*Mem)) 1972 DK = diag::err_anonymous_record_with_static; 1973 Diag((*Mem)->getLocation(), DK) 1974 << (int)Record->isUnion(); 1975 Invalid = true; 1976 } 1977 } 1978 } 1979 1980 if (!Record->isUnion() && !Owner->isRecord()) { 1981 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1982 << (int)getLangOptions().CPlusPlus; 1983 Invalid = true; 1984 } 1985 1986 // Mock up a declarator. 1987 Declarator Dc(DS, Declarator::TypeNameContext); 1988 TypeSourceInfo *TInfo = 0; 1989 GetTypeForDeclarator(Dc, S, &TInfo); 1990 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1991 1992 // Create a declaration for this anonymous struct/union. 1993 NamedDecl *Anon = 0; 1994 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1995 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1996 /*IdentifierInfo=*/0, 1997 Context.getTypeDeclType(Record), 1998 TInfo, 1999 /*BitWidth=*/0, /*Mutable=*/false); 2000 Anon->setAccess(AS_public); 2001 if (getLangOptions().CPlusPlus) 2002 FieldCollector->Add(cast<FieldDecl>(Anon)); 2003 } else { 2004 VarDecl::StorageClass SC; 2005 switch (DS.getStorageClassSpec()) { 2006 default: assert(0 && "Unknown storage class!"); 2007 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2008 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2009 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2010 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2011 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2012 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2013 case DeclSpec::SCS_mutable: 2014 // mutable can only appear on non-static class members, so it's always 2015 // an error here 2016 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2017 Invalid = true; 2018 SC = VarDecl::None; 2019 break; 2020 } 2021 2022 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 2023 /*IdentifierInfo=*/0, 2024 Context.getTypeDeclType(Record), 2025 TInfo, 2026 SC); 2027 } 2028 Anon->setImplicit(); 2029 2030 // Add the anonymous struct/union object to the current 2031 // context. We'll be referencing this object when we refer to one of 2032 // its members. 2033 Owner->addDecl(Anon); 2034 2035 // Inject the members of the anonymous struct/union into the owning 2036 // context and into the identifier resolver chain for name lookup 2037 // purposes. 2038 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 2039 Invalid = true; 2040 2041 // Mark this as an anonymous struct/union type. Note that we do not 2042 // do this until after we have already checked and injected the 2043 // members of this anonymous struct/union type, because otherwise 2044 // the members could be injected twice: once by DeclContext when it 2045 // builds its lookup table, and once by 2046 // InjectAnonymousStructOrUnionMembers. 2047 Record->setAnonymousStructOrUnion(true); 2048 2049 if (Invalid) 2050 Anon->setInvalidDecl(); 2051 2052 return DeclPtrTy::make(Anon); 2053} 2054 2055 2056/// GetNameForDeclarator - Determine the full declaration name for the 2057/// given Declarator. 2058DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 2059 return GetNameFromUnqualifiedId(D.getName()); 2060} 2061 2062/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 2063DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2064 switch (Name.getKind()) { 2065 case UnqualifiedId::IK_Identifier: 2066 return DeclarationName(Name.Identifier); 2067 2068 case UnqualifiedId::IK_OperatorFunctionId: 2069 return Context.DeclarationNames.getCXXOperatorName( 2070 Name.OperatorFunctionId.Operator); 2071 2072 case UnqualifiedId::IK_LiteralOperatorId: 2073 return Context.DeclarationNames.getCXXLiteralOperatorName( 2074 Name.Identifier); 2075 2076 case UnqualifiedId::IK_ConversionFunctionId: { 2077 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 2078 if (Ty.isNull()) 2079 return DeclarationName(); 2080 2081 return Context.DeclarationNames.getCXXConversionFunctionName( 2082 Context.getCanonicalType(Ty)); 2083 } 2084 2085 case UnqualifiedId::IK_ConstructorName: { 2086 QualType Ty = GetTypeFromParser(Name.ConstructorName); 2087 if (Ty.isNull()) 2088 return DeclarationName(); 2089 2090 return Context.DeclarationNames.getCXXConstructorName( 2091 Context.getCanonicalType(Ty)); 2092 } 2093 2094 case UnqualifiedId::IK_ConstructorTemplateId: { 2095 // In well-formed code, we can only have a constructor 2096 // template-id that refers to the current context, so go there 2097 // to find the actual type being constructed. 2098 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2099 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2100 return DeclarationName(); 2101 2102 // Determine the type of the class being constructed. 2103 QualType CurClassType; 2104 if (ClassTemplateDecl *ClassTemplate 2105 = CurClass->getDescribedClassTemplate()) 2106 CurClassType = ClassTemplate->getInjectedClassNameType(Context); 2107 else 2108 CurClassType = Context.getTypeDeclType(CurClass); 2109 2110 // FIXME: Check two things: that the template-id names the same type as 2111 // CurClassType, and that the template-id does not occur when the name 2112 // was qualified. 2113 2114 return Context.DeclarationNames.getCXXConstructorName( 2115 Context.getCanonicalType(CurClassType)); 2116 } 2117 2118 case UnqualifiedId::IK_DestructorName: { 2119 QualType Ty = GetTypeFromParser(Name.DestructorName); 2120 if (Ty.isNull()) 2121 return DeclarationName(); 2122 2123 return Context.DeclarationNames.getCXXDestructorName( 2124 Context.getCanonicalType(Ty)); 2125 } 2126 2127 case UnqualifiedId::IK_TemplateId: { 2128 TemplateName TName 2129 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2130 return Context.getNameForTemplate(TName); 2131 } 2132 } 2133 2134 assert(false && "Unknown name kind"); 2135 return DeclarationName(); 2136} 2137 2138/// isNearlyMatchingFunction - Determine whether the C++ functions 2139/// Declaration and Definition are "nearly" matching. This heuristic 2140/// is used to improve diagnostics in the case where an out-of-line 2141/// function definition doesn't match any declaration within 2142/// the class or namespace. 2143static bool isNearlyMatchingFunction(ASTContext &Context, 2144 FunctionDecl *Declaration, 2145 FunctionDecl *Definition) { 2146 if (Declaration->param_size() != Definition->param_size()) 2147 return false; 2148 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2149 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2150 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2151 2152 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2153 DefParamTy.getNonReferenceType())) 2154 return false; 2155 } 2156 2157 return true; 2158} 2159 2160Sema::DeclPtrTy 2161Sema::HandleDeclarator(Scope *S, Declarator &D, 2162 MultiTemplateParamsArg TemplateParamLists, 2163 bool IsFunctionDefinition) { 2164 DeclarationName Name = GetNameForDeclarator(D); 2165 2166 // All of these full declarators require an identifier. If it doesn't have 2167 // one, the ParsedFreeStandingDeclSpec action should be used. 2168 if (!Name) { 2169 if (!D.isInvalidType()) // Reject this if we think it is valid. 2170 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2171 diag::err_declarator_need_ident) 2172 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2173 return DeclPtrTy(); 2174 } 2175 2176 // The scope passed in may not be a decl scope. Zip up the scope tree until 2177 // we find one that is. 2178 while ((S->getFlags() & Scope::DeclScope) == 0 || 2179 (S->getFlags() & Scope::TemplateParamScope) != 0) 2180 S = S->getParent(); 2181 2182 // If this is an out-of-line definition of a member of a class template 2183 // or class template partial specialization, we may need to rebuild the 2184 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 2185 // for more information. 2186 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 2187 // handle expressions properly. 2188 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 2189 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 2190 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 2191 (DS.getTypeSpecType() == DeclSpec::TST_typename || 2192 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 2193 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 2194 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 2195 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 2196 // FIXME: Preserve type source info. 2197 QualType T = GetTypeFromParser(DS.getTypeRep()); 2198 2199 DeclContext *SavedContext = CurContext; 2200 CurContext = DC; 2201 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 2202 CurContext = SavedContext; 2203 2204 if (T.isNull()) 2205 return DeclPtrTy(); 2206 DS.UpdateTypeRep(T.getAsOpaquePtr()); 2207 } 2208 } 2209 2210 DeclContext *DC; 2211 NamedDecl *New; 2212 2213 TypeSourceInfo *TInfo = 0; 2214 QualType R = GetTypeForDeclarator(D, S, &TInfo); 2215 2216 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2217 ForRedeclaration); 2218 2219 // See if this is a redefinition of a variable in the same scope. 2220 if (D.getCXXScopeSpec().isInvalid()) { 2221 DC = CurContext; 2222 D.setInvalidType(); 2223 } else if (!D.getCXXScopeSpec().isSet()) { 2224 bool IsLinkageLookup = false; 2225 2226 // If the declaration we're planning to build will be a function 2227 // or object with linkage, then look for another declaration with 2228 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2229 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2230 /* Do nothing*/; 2231 else if (R->isFunctionType()) { 2232 if (CurContext->isFunctionOrMethod() || 2233 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2234 IsLinkageLookup = true; 2235 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2236 IsLinkageLookup = true; 2237 else if (CurContext->getLookupContext()->isTranslationUnit() && 2238 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2239 IsLinkageLookup = true; 2240 2241 if (IsLinkageLookup) 2242 Previous.clear(LookupRedeclarationWithLinkage); 2243 2244 DC = CurContext; 2245 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2246 } else { // Something like "int foo::x;" 2247 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2248 2249 if (!DC) { 2250 // If we could not compute the declaration context, it's because the 2251 // declaration context is dependent but does not refer to a class, 2252 // class template, or class template partial specialization. Complain 2253 // and return early, to avoid the coming semantic disaster. 2254 Diag(D.getIdentifierLoc(), 2255 diag::err_template_qualified_declarator_no_match) 2256 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2257 << D.getCXXScopeSpec().getRange(); 2258 return DeclPtrTy(); 2259 } 2260 2261 if (!DC->isDependentContext() && 2262 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2263 return DeclPtrTy(); 2264 2265 LookupQualifiedName(Previous, DC); 2266 2267 // Don't consider using declarations as previous declarations for 2268 // out-of-line members. 2269 RemoveUsingDecls(Previous); 2270 2271 // C++ 7.3.1.2p2: 2272 // Members (including explicit specializations of templates) of a named 2273 // namespace can also be defined outside that namespace by explicit 2274 // qualification of the name being defined, provided that the entity being 2275 // defined was already declared in the namespace and the definition appears 2276 // after the point of declaration in a namespace that encloses the 2277 // declarations namespace. 2278 // 2279 // Note that we only check the context at this point. We don't yet 2280 // have enough information to make sure that PrevDecl is actually 2281 // the declaration we want to match. For example, given: 2282 // 2283 // class X { 2284 // void f(); 2285 // void f(float); 2286 // }; 2287 // 2288 // void X::f(int) { } // ill-formed 2289 // 2290 // In this case, PrevDecl will point to the overload set 2291 // containing the two f's declared in X, but neither of them 2292 // matches. 2293 2294 // First check whether we named the global scope. 2295 if (isa<TranslationUnitDecl>(DC)) { 2296 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2297 << Name << D.getCXXScopeSpec().getRange(); 2298 } else { 2299 DeclContext *Cur = CurContext; 2300 while (isa<LinkageSpecDecl>(Cur)) 2301 Cur = Cur->getParent(); 2302 if (!Cur->Encloses(DC)) { 2303 // The qualifying scope doesn't enclose the original declaration. 2304 // Emit diagnostic based on current scope. 2305 SourceLocation L = D.getIdentifierLoc(); 2306 SourceRange R = D.getCXXScopeSpec().getRange(); 2307 if (isa<FunctionDecl>(Cur)) 2308 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2309 else 2310 Diag(L, diag::err_invalid_declarator_scope) 2311 << Name << cast<NamedDecl>(DC) << R; 2312 D.setInvalidType(); 2313 } 2314 } 2315 } 2316 2317 if (Previous.isSingleResult() && 2318 Previous.getFoundDecl()->isTemplateParameter()) { 2319 // Maybe we will complain about the shadowed template parameter. 2320 if (!D.isInvalidType()) 2321 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2322 Previous.getFoundDecl())) 2323 D.setInvalidType(); 2324 2325 // Just pretend that we didn't see the previous declaration. 2326 Previous.clear(); 2327 } 2328 2329 // In C++, the previous declaration we find might be a tag type 2330 // (class or enum). In this case, the new declaration will hide the 2331 // tag type. Note that this does does not apply if we're declaring a 2332 // typedef (C++ [dcl.typedef]p4). 2333 if (Previous.isSingleTagDecl() && 2334 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2335 Previous.clear(); 2336 2337 bool Redeclaration = false; 2338 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2339 if (TemplateParamLists.size()) { 2340 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2341 return DeclPtrTy(); 2342 } 2343 2344 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2345 } else if (R->isFunctionType()) { 2346 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2347 move(TemplateParamLists), 2348 IsFunctionDefinition, Redeclaration); 2349 } else { 2350 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2351 move(TemplateParamLists), 2352 Redeclaration); 2353 } 2354 2355 if (New == 0) 2356 return DeclPtrTy(); 2357 2358 // If this has an identifier and is not an invalid redeclaration or 2359 // function template specialization, add it to the scope stack. 2360 if (Name && !(Redeclaration && New->isInvalidDecl())) 2361 PushOnScopeChains(New, S); 2362 2363 return DeclPtrTy::make(New); 2364} 2365 2366/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2367/// types into constant array types in certain situations which would otherwise 2368/// be errors (for GCC compatibility). 2369static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2370 ASTContext &Context, 2371 bool &SizeIsNegative) { 2372 // This method tries to turn a variable array into a constant 2373 // array even when the size isn't an ICE. This is necessary 2374 // for compatibility with code that depends on gcc's buggy 2375 // constant expression folding, like struct {char x[(int)(char*)2];} 2376 SizeIsNegative = false; 2377 2378 QualifierCollector Qs; 2379 const Type *Ty = Qs.strip(T); 2380 2381 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2382 QualType Pointee = PTy->getPointeeType(); 2383 QualType FixedType = 2384 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2385 if (FixedType.isNull()) return FixedType; 2386 FixedType = Context.getPointerType(FixedType); 2387 return Qs.apply(FixedType); 2388 } 2389 2390 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2391 if (!VLATy) 2392 return QualType(); 2393 // FIXME: We should probably handle this case 2394 if (VLATy->getElementType()->isVariablyModifiedType()) 2395 return QualType(); 2396 2397 Expr::EvalResult EvalResult; 2398 if (!VLATy->getSizeExpr() || 2399 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2400 !EvalResult.Val.isInt()) 2401 return QualType(); 2402 2403 llvm::APSInt &Res = EvalResult.Val.getInt(); 2404 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2405 // TODO: preserve the size expression in declarator info 2406 return Context.getConstantArrayType(VLATy->getElementType(), 2407 Res, ArrayType::Normal, 0); 2408 } 2409 2410 SizeIsNegative = true; 2411 return QualType(); 2412} 2413 2414/// \brief Register the given locally-scoped external C declaration so 2415/// that it can be found later for redeclarations 2416void 2417Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2418 const LookupResult &Previous, 2419 Scope *S) { 2420 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2421 "Decl is not a locally-scoped decl!"); 2422 // Note that we have a locally-scoped external with this name. 2423 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2424 2425 if (!Previous.isSingleResult()) 2426 return; 2427 2428 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2429 2430 // If there was a previous declaration of this variable, it may be 2431 // in our identifier chain. Update the identifier chain with the new 2432 // declaration. 2433 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2434 // The previous declaration was found on the identifer resolver 2435 // chain, so remove it from its scope. 2436 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2437 S = S->getParent(); 2438 2439 if (S) 2440 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2441 } 2442} 2443 2444/// \brief Diagnose function specifiers on a declaration of an identifier that 2445/// does not identify a function. 2446void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2447 // FIXME: We should probably indicate the identifier in question to avoid 2448 // confusion for constructs like "inline int a(), b;" 2449 if (D.getDeclSpec().isInlineSpecified()) 2450 Diag(D.getDeclSpec().getInlineSpecLoc(), 2451 diag::err_inline_non_function); 2452 2453 if (D.getDeclSpec().isVirtualSpecified()) 2454 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2455 diag::err_virtual_non_function); 2456 2457 if (D.getDeclSpec().isExplicitSpecified()) 2458 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2459 diag::err_explicit_non_function); 2460} 2461 2462NamedDecl* 2463Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2464 QualType R, TypeSourceInfo *TInfo, 2465 LookupResult &Previous, bool &Redeclaration) { 2466 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2467 if (D.getCXXScopeSpec().isSet()) { 2468 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2469 << D.getCXXScopeSpec().getRange(); 2470 D.setInvalidType(); 2471 // Pretend we didn't see the scope specifier. 2472 DC = 0; 2473 } 2474 2475 if (getLangOptions().CPlusPlus) { 2476 // Check that there are no default arguments (C++ only). 2477 CheckExtraCXXDefaultArguments(D); 2478 } 2479 2480 DiagnoseFunctionSpecifiers(D); 2481 2482 if (D.getDeclSpec().isThreadSpecified()) 2483 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2484 2485 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2486 if (!NewTD) return 0; 2487 2488 // Handle attributes prior to checking for duplicates in MergeVarDecl 2489 ProcessDeclAttributes(S, NewTD, D); 2490 2491 // Merge the decl with the existing one if appropriate. If the decl is 2492 // in an outer scope, it isn't the same thing. 2493 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2494 if (!Previous.empty()) { 2495 Redeclaration = true; 2496 MergeTypeDefDecl(NewTD, Previous); 2497 } 2498 2499 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2500 // then it shall have block scope. 2501 QualType T = NewTD->getUnderlyingType(); 2502 if (T->isVariablyModifiedType()) { 2503 CurFunctionNeedsScopeChecking = true; 2504 2505 if (S->getFnParent() == 0) { 2506 bool SizeIsNegative; 2507 QualType FixedTy = 2508 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2509 if (!FixedTy.isNull()) { 2510 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2511 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2512 } else { 2513 if (SizeIsNegative) 2514 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2515 else if (T->isVariableArrayType()) 2516 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2517 else 2518 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2519 NewTD->setInvalidDecl(); 2520 } 2521 } 2522 } 2523 2524 // If this is the C FILE type, notify the AST context. 2525 if (IdentifierInfo *II = NewTD->getIdentifier()) 2526 if (!NewTD->isInvalidDecl() && 2527 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2528 if (II->isStr("FILE")) 2529 Context.setFILEDecl(NewTD); 2530 else if (II->isStr("jmp_buf")) 2531 Context.setjmp_bufDecl(NewTD); 2532 else if (II->isStr("sigjmp_buf")) 2533 Context.setsigjmp_bufDecl(NewTD); 2534 } 2535 2536 return NewTD; 2537} 2538 2539/// \brief Determines whether the given declaration is an out-of-scope 2540/// previous declaration. 2541/// 2542/// This routine should be invoked when name lookup has found a 2543/// previous declaration (PrevDecl) that is not in the scope where a 2544/// new declaration by the same name is being introduced. If the new 2545/// declaration occurs in a local scope, previous declarations with 2546/// linkage may still be considered previous declarations (C99 2547/// 6.2.2p4-5, C++ [basic.link]p6). 2548/// 2549/// \param PrevDecl the previous declaration found by name 2550/// lookup 2551/// 2552/// \param DC the context in which the new declaration is being 2553/// declared. 2554/// 2555/// \returns true if PrevDecl is an out-of-scope previous declaration 2556/// for a new delcaration with the same name. 2557static bool 2558isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2559 ASTContext &Context) { 2560 if (!PrevDecl) 2561 return 0; 2562 2563 if (!PrevDecl->hasLinkage()) 2564 return false; 2565 2566 if (Context.getLangOptions().CPlusPlus) { 2567 // C++ [basic.link]p6: 2568 // If there is a visible declaration of an entity with linkage 2569 // having the same name and type, ignoring entities declared 2570 // outside the innermost enclosing namespace scope, the block 2571 // scope declaration declares that same entity and receives the 2572 // linkage of the previous declaration. 2573 DeclContext *OuterContext = DC->getLookupContext(); 2574 if (!OuterContext->isFunctionOrMethod()) 2575 // This rule only applies to block-scope declarations. 2576 return false; 2577 else { 2578 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2579 if (PrevOuterContext->isRecord()) 2580 // We found a member function: ignore it. 2581 return false; 2582 else { 2583 // Find the innermost enclosing namespace for the new and 2584 // previous declarations. 2585 while (!OuterContext->isFileContext()) 2586 OuterContext = OuterContext->getParent(); 2587 while (!PrevOuterContext->isFileContext()) 2588 PrevOuterContext = PrevOuterContext->getParent(); 2589 2590 // The previous declaration is in a different namespace, so it 2591 // isn't the same function. 2592 if (OuterContext->getPrimaryContext() != 2593 PrevOuterContext->getPrimaryContext()) 2594 return false; 2595 } 2596 } 2597 } 2598 2599 return true; 2600} 2601 2602NamedDecl* 2603Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2604 QualType R, TypeSourceInfo *TInfo, 2605 LookupResult &Previous, 2606 MultiTemplateParamsArg TemplateParamLists, 2607 bool &Redeclaration) { 2608 DeclarationName Name = GetNameForDeclarator(D); 2609 2610 // Check that there are no default arguments (C++ only). 2611 if (getLangOptions().CPlusPlus) 2612 CheckExtraCXXDefaultArguments(D); 2613 2614 VarDecl *NewVD; 2615 VarDecl::StorageClass SC; 2616 switch (D.getDeclSpec().getStorageClassSpec()) { 2617 default: assert(0 && "Unknown storage class!"); 2618 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2619 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2620 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2621 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2622 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2623 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2624 case DeclSpec::SCS_mutable: 2625 // mutable can only appear on non-static class members, so it's always 2626 // an error here 2627 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2628 D.setInvalidType(); 2629 SC = VarDecl::None; 2630 break; 2631 } 2632 2633 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2634 if (!II) { 2635 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2636 << Name.getAsString(); 2637 return 0; 2638 } 2639 2640 DiagnoseFunctionSpecifiers(D); 2641 2642 if (!DC->isRecord() && S->getFnParent() == 0) { 2643 // C99 6.9p2: The storage-class specifiers auto and register shall not 2644 // appear in the declaration specifiers in an external declaration. 2645 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2646 2647 // If this is a register variable with an asm label specified, then this 2648 // is a GNU extension. 2649 if (SC == VarDecl::Register && D.getAsmLabel()) 2650 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2651 else 2652 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2653 D.setInvalidType(); 2654 } 2655 } 2656 if (DC->isRecord() && !CurContext->isRecord()) { 2657 // This is an out-of-line definition of a static data member. 2658 if (SC == VarDecl::Static) { 2659 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2660 diag::err_static_out_of_line) 2661 << CodeModificationHint::CreateRemoval( 2662 D.getDeclSpec().getStorageClassSpecLoc()); 2663 } else if (SC == VarDecl::None) 2664 SC = VarDecl::Static; 2665 } 2666 if (SC == VarDecl::Static) { 2667 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2668 if (RD->isLocalClass()) 2669 Diag(D.getIdentifierLoc(), 2670 diag::err_static_data_member_not_allowed_in_local_class) 2671 << Name << RD->getDeclName(); 2672 } 2673 } 2674 2675 // Match up the template parameter lists with the scope specifier, then 2676 // determine whether we have a template or a template specialization. 2677 bool isExplicitSpecialization = false; 2678 if (TemplateParameterList *TemplateParams 2679 = MatchTemplateParametersToScopeSpecifier( 2680 D.getDeclSpec().getSourceRange().getBegin(), 2681 D.getCXXScopeSpec(), 2682 (TemplateParameterList**)TemplateParamLists.get(), 2683 TemplateParamLists.size(), 2684 isExplicitSpecialization)) { 2685 if (TemplateParams->size() > 0) { 2686 // There is no such thing as a variable template. 2687 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2688 << II 2689 << SourceRange(TemplateParams->getTemplateLoc(), 2690 TemplateParams->getRAngleLoc()); 2691 return 0; 2692 } else { 2693 // There is an extraneous 'template<>' for this variable. Complain 2694 // about it, but allow the declaration of the variable. 2695 Diag(TemplateParams->getTemplateLoc(), 2696 diag::err_template_variable_noparams) 2697 << II 2698 << SourceRange(TemplateParams->getTemplateLoc(), 2699 TemplateParams->getRAngleLoc()); 2700 2701 isExplicitSpecialization = true; 2702 } 2703 } 2704 2705 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2706 II, R, TInfo, SC); 2707 2708 if (D.isInvalidType()) 2709 NewVD->setInvalidDecl(); 2710 2711 if (D.getDeclSpec().isThreadSpecified()) { 2712 if (NewVD->hasLocalStorage()) 2713 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2714 else if (!Context.Target.isTLSSupported()) 2715 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2716 else 2717 NewVD->setThreadSpecified(true); 2718 } 2719 2720 // Set the lexical context. If the declarator has a C++ scope specifier, the 2721 // lexical context will be different from the semantic context. 2722 NewVD->setLexicalDeclContext(CurContext); 2723 2724 // Handle attributes prior to checking for duplicates in MergeVarDecl 2725 ProcessDeclAttributes(S, NewVD, D); 2726 2727 // Handle GNU asm-label extension (encoded as an attribute). 2728 if (Expr *E = (Expr*) D.getAsmLabel()) { 2729 // The parser guarantees this is a string. 2730 StringLiteral *SE = cast<StringLiteral>(E); 2731 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2732 } 2733 2734 // Don't consider existing declarations that are in a different 2735 // scope and are out-of-semantic-context declarations (if the new 2736 // declaration has linkage). 2737 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2738 2739 // Merge the decl with the existing one if appropriate. 2740 if (!Previous.empty()) { 2741 if (Previous.isSingleResult() && 2742 isa<FieldDecl>(Previous.getFoundDecl()) && 2743 D.getCXXScopeSpec().isSet()) { 2744 // The user tried to define a non-static data member 2745 // out-of-line (C++ [dcl.meaning]p1). 2746 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2747 << D.getCXXScopeSpec().getRange(); 2748 Previous.clear(); 2749 NewVD->setInvalidDecl(); 2750 } 2751 } else if (D.getCXXScopeSpec().isSet()) { 2752 // No previous declaration in the qualifying scope. 2753 Diag(D.getIdentifierLoc(), diag::err_no_member) 2754 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2755 << D.getCXXScopeSpec().getRange(); 2756 NewVD->setInvalidDecl(); 2757 } 2758 2759 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2760 2761 // This is an explicit specialization of a static data member. Check it. 2762 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2763 CheckMemberSpecialization(NewVD, Previous)) 2764 NewVD->setInvalidDecl(); 2765 2766 // attributes declared post-definition are currently ignored 2767 if (Previous.isSingleResult()) { 2768 const VarDecl *Def = 0; 2769 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2770 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2771 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2772 Diag(Def->getLocation(), diag::note_previous_definition); 2773 } 2774 } 2775 2776 // If this is a locally-scoped extern C variable, update the map of 2777 // such variables. 2778 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2779 !NewVD->isInvalidDecl()) 2780 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2781 2782 return NewVD; 2783} 2784 2785/// \brief Perform semantic checking on a newly-created variable 2786/// declaration. 2787/// 2788/// This routine performs all of the type-checking required for a 2789/// variable declaration once it has been built. It is used both to 2790/// check variables after they have been parsed and their declarators 2791/// have been translated into a declaration, and to check variables 2792/// that have been instantiated from a template. 2793/// 2794/// Sets NewVD->isInvalidDecl() if an error was encountered. 2795void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2796 LookupResult &Previous, 2797 bool &Redeclaration) { 2798 // If the decl is already known invalid, don't check it. 2799 if (NewVD->isInvalidDecl()) 2800 return; 2801 2802 QualType T = NewVD->getType(); 2803 2804 if (T->isObjCInterfaceType()) { 2805 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2806 return NewVD->setInvalidDecl(); 2807 } 2808 2809 // Emit an error if an address space was applied to decl with local storage. 2810 // This includes arrays of objects with address space qualifiers, but not 2811 // automatic variables that point to other address spaces. 2812 // ISO/IEC TR 18037 S5.1.2 2813 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2814 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2815 return NewVD->setInvalidDecl(); 2816 } 2817 2818 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2819 && !NewVD->hasAttr<BlocksAttr>()) 2820 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2821 2822 bool isVM = T->isVariablyModifiedType(); 2823 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2824 NewVD->hasAttr<BlocksAttr>()) 2825 CurFunctionNeedsScopeChecking = true; 2826 2827 if ((isVM && NewVD->hasLinkage()) || 2828 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2829 bool SizeIsNegative; 2830 QualType FixedTy = 2831 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2832 2833 if (FixedTy.isNull() && T->isVariableArrayType()) { 2834 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2835 // FIXME: This won't give the correct result for 2836 // int a[10][n]; 2837 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2838 2839 if (NewVD->isFileVarDecl()) 2840 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2841 << SizeRange; 2842 else if (NewVD->getStorageClass() == VarDecl::Static) 2843 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2844 << SizeRange; 2845 else 2846 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2847 << SizeRange; 2848 return NewVD->setInvalidDecl(); 2849 } 2850 2851 if (FixedTy.isNull()) { 2852 if (NewVD->isFileVarDecl()) 2853 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2854 else 2855 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2856 return NewVD->setInvalidDecl(); 2857 } 2858 2859 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2860 NewVD->setType(FixedTy); 2861 } 2862 2863 if (Previous.empty() && NewVD->isExternC()) { 2864 // Since we did not find anything by this name and we're declaring 2865 // an extern "C" variable, look for a non-visible extern "C" 2866 // declaration with the same name. 2867 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2868 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2869 if (Pos != LocallyScopedExternalDecls.end()) 2870 Previous.addDecl(Pos->second); 2871 } 2872 2873 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2874 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2875 << T; 2876 return NewVD->setInvalidDecl(); 2877 } 2878 2879 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2880 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2881 return NewVD->setInvalidDecl(); 2882 } 2883 2884 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2885 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2886 return NewVD->setInvalidDecl(); 2887 } 2888 2889 if (!Previous.empty()) { 2890 Redeclaration = true; 2891 MergeVarDecl(NewVD, Previous); 2892 } 2893} 2894 2895/// \brief Data used with FindOverriddenMethod 2896struct FindOverriddenMethodData { 2897 Sema *S; 2898 CXXMethodDecl *Method; 2899}; 2900 2901/// \brief Member lookup function that determines whether a given C++ 2902/// method overrides a method in a base class, to be used with 2903/// CXXRecordDecl::lookupInBases(). 2904static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2905 CXXBasePath &Path, 2906 void *UserData) { 2907 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2908 2909 FindOverriddenMethodData *Data 2910 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2911 2912 DeclarationName Name = Data->Method->getDeclName(); 2913 2914 // FIXME: Do we care about other names here too? 2915 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2916 // We really want to find the base class constructor here. 2917 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2918 CanQualType CT = Data->S->Context.getCanonicalType(T); 2919 2920 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2921 } 2922 2923 for (Path.Decls = BaseRecord->lookup(Name); 2924 Path.Decls.first != Path.Decls.second; 2925 ++Path.Decls.first) { 2926 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2927 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2928 return true; 2929 } 2930 } 2931 2932 return false; 2933} 2934 2935/// AddOverriddenMethods - See if a method overrides any in the base classes, 2936/// and if so, check that it's a valid override and remember it. 2937void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2938 // Look for virtual methods in base classes that this method might override. 2939 CXXBasePaths Paths; 2940 FindOverriddenMethodData Data; 2941 Data.Method = MD; 2942 Data.S = this; 2943 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2944 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2945 E = Paths.found_decls_end(); I != E; ++I) { 2946 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2947 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2948 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2949 !CheckOverridingFunctionAttributes(MD, OldMD)) 2950 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2951 } 2952 } 2953 } 2954} 2955 2956NamedDecl* 2957Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2958 QualType R, TypeSourceInfo *TInfo, 2959 LookupResult &Previous, 2960 MultiTemplateParamsArg TemplateParamLists, 2961 bool IsFunctionDefinition, bool &Redeclaration) { 2962 assert(R.getTypePtr()->isFunctionType()); 2963 2964 DeclarationName Name = GetNameForDeclarator(D); 2965 FunctionDecl::StorageClass SC = FunctionDecl::None; 2966 switch (D.getDeclSpec().getStorageClassSpec()) { 2967 default: assert(0 && "Unknown storage class!"); 2968 case DeclSpec::SCS_auto: 2969 case DeclSpec::SCS_register: 2970 case DeclSpec::SCS_mutable: 2971 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2972 diag::err_typecheck_sclass_func); 2973 D.setInvalidType(); 2974 break; 2975 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2976 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2977 case DeclSpec::SCS_static: { 2978 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2979 // C99 6.7.1p5: 2980 // The declaration of an identifier for a function that has 2981 // block scope shall have no explicit storage-class specifier 2982 // other than extern 2983 // See also (C++ [dcl.stc]p4). 2984 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2985 diag::err_static_block_func); 2986 SC = FunctionDecl::None; 2987 } else 2988 SC = FunctionDecl::Static; 2989 break; 2990 } 2991 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2992 } 2993 2994 if (D.getDeclSpec().isThreadSpecified()) 2995 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2996 2997 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2998 bool isInline = D.getDeclSpec().isInlineSpecified(); 2999 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3000 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3001 3002 // Check that the return type is not an abstract class type. 3003 // For record types, this is done by the AbstractClassUsageDiagnoser once 3004 // the class has been completely parsed. 3005 if (!DC->isRecord() && 3006 RequireNonAbstractType(D.getIdentifierLoc(), 3007 R->getAs<FunctionType>()->getResultType(), 3008 diag::err_abstract_type_in_decl, 3009 AbstractReturnType)) 3010 D.setInvalidType(); 3011 3012 // Do not allow returning a objc interface by-value. 3013 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 3014 Diag(D.getIdentifierLoc(), 3015 diag::err_object_cannot_be_passed_returned_by_value) << 0 3016 << R->getAs<FunctionType>()->getResultType(); 3017 D.setInvalidType(); 3018 } 3019 3020 bool isVirtualOkay = false; 3021 FunctionDecl *NewFD; 3022 3023 if (isFriend) { 3024 // C++ [class.friend]p5 3025 // A function can be defined in a friend declaration of a 3026 // class . . . . Such a function is implicitly inline. 3027 isInline |= IsFunctionDefinition; 3028 } 3029 3030 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3031 // This is a C++ constructor declaration. 3032 assert(DC->isRecord() && 3033 "Constructors can only be declared in a member context"); 3034 3035 R = CheckConstructorDeclarator(D, R, SC); 3036 3037 // Create the new declaration 3038 NewFD = CXXConstructorDecl::Create(Context, 3039 cast<CXXRecordDecl>(DC), 3040 D.getIdentifierLoc(), Name, R, TInfo, 3041 isExplicit, isInline, 3042 /*isImplicitlyDeclared=*/false); 3043 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3044 // This is a C++ destructor declaration. 3045 if (DC->isRecord()) { 3046 R = CheckDestructorDeclarator(D, SC); 3047 3048 NewFD = CXXDestructorDecl::Create(Context, 3049 cast<CXXRecordDecl>(DC), 3050 D.getIdentifierLoc(), Name, R, 3051 isInline, 3052 /*isImplicitlyDeclared=*/false); 3053 3054 isVirtualOkay = true; 3055 } else { 3056 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3057 3058 // Create a FunctionDecl to satisfy the function definition parsing 3059 // code path. 3060 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3061 Name, R, TInfo, SC, isInline, 3062 /*hasPrototype=*/true); 3063 D.setInvalidType(); 3064 } 3065 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3066 if (!DC->isRecord()) { 3067 Diag(D.getIdentifierLoc(), 3068 diag::err_conv_function_not_member); 3069 return 0; 3070 } 3071 3072 CheckConversionDeclarator(D, R, SC); 3073 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3074 D.getIdentifierLoc(), Name, R, TInfo, 3075 isInline, isExplicit); 3076 3077 isVirtualOkay = true; 3078 } else if (DC->isRecord()) { 3079 // If the of the function is the same as the name of the record, then this 3080 // must be an invalid constructor that has a return type. 3081 // (The parser checks for a return type and makes the declarator a 3082 // constructor if it has no return type). 3083 // must have an invalid constructor that has a return type 3084 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3085 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3086 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3087 << SourceRange(D.getIdentifierLoc()); 3088 return 0; 3089 } 3090 3091 bool isStatic = SC == FunctionDecl::Static; 3092 3093 // [class.free]p1: 3094 // Any allocation function for a class T is a static member 3095 // (even if not explicitly declared static). 3096 if (Name.getCXXOverloadedOperator() == OO_New || 3097 Name.getCXXOverloadedOperator() == OO_Array_New) 3098 isStatic = true; 3099 3100 // [class.free]p6 Any deallocation function for a class X is a static member 3101 // (even if not explicitly declared static). 3102 if (Name.getCXXOverloadedOperator() == OO_Delete || 3103 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3104 isStatic = true; 3105 3106 // This is a C++ method declaration. 3107 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3108 D.getIdentifierLoc(), Name, R, TInfo, 3109 isStatic, isInline); 3110 3111 isVirtualOkay = !isStatic; 3112 } else { 3113 // Determine whether the function was written with a 3114 // prototype. This true when: 3115 // - we're in C++ (where every function has a prototype), 3116 // - there is a prototype in the declarator, or 3117 // - the type R of the function is some kind of typedef or other reference 3118 // to a type name (which eventually refers to a function type). 3119 bool HasPrototype = 3120 getLangOptions().CPlusPlus || 3121 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3122 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3123 3124 NewFD = FunctionDecl::Create(Context, DC, 3125 D.getIdentifierLoc(), 3126 Name, R, TInfo, SC, isInline, HasPrototype); 3127 } 3128 3129 if (D.isInvalidType()) 3130 NewFD->setInvalidDecl(); 3131 3132 // Set the lexical context. If the declarator has a C++ 3133 // scope specifier, or is the object of a friend declaration, the 3134 // lexical context will be different from the semantic context. 3135 NewFD->setLexicalDeclContext(CurContext); 3136 3137 // Match up the template parameter lists with the scope specifier, then 3138 // determine whether we have a template or a template specialization. 3139 FunctionTemplateDecl *FunctionTemplate = 0; 3140 bool isExplicitSpecialization = false; 3141 bool isFunctionTemplateSpecialization = false; 3142 if (TemplateParameterList *TemplateParams 3143 = MatchTemplateParametersToScopeSpecifier( 3144 D.getDeclSpec().getSourceRange().getBegin(), 3145 D.getCXXScopeSpec(), 3146 (TemplateParameterList**)TemplateParamLists.get(), 3147 TemplateParamLists.size(), 3148 isExplicitSpecialization)) { 3149 if (TemplateParams->size() > 0) { 3150 // This is a function template 3151 3152 // Check that we can declare a template here. 3153 if (CheckTemplateDeclScope(S, TemplateParams)) 3154 return 0; 3155 3156 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3157 NewFD->getLocation(), 3158 Name, TemplateParams, 3159 NewFD); 3160 FunctionTemplate->setLexicalDeclContext(CurContext); 3161 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3162 } else { 3163 // This is a function template specialization. 3164 isFunctionTemplateSpecialization = true; 3165 } 3166 3167 // FIXME: Free this memory properly. 3168 TemplateParamLists.release(); 3169 } 3170 3171 // C++ [dcl.fct.spec]p5: 3172 // The virtual specifier shall only be used in declarations of 3173 // nonstatic class member functions that appear within a 3174 // member-specification of a class declaration; see 10.3. 3175 // 3176 if (isVirtual && !NewFD->isInvalidDecl()) { 3177 if (!isVirtualOkay) { 3178 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3179 diag::err_virtual_non_function); 3180 } else if (!CurContext->isRecord()) { 3181 // 'virtual' was specified outside of the class. 3182 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3183 << CodeModificationHint::CreateRemoval( 3184 D.getDeclSpec().getVirtualSpecLoc()); 3185 } else { 3186 // Okay: Add virtual to the method. 3187 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3188 CurClass->setMethodAsVirtual(NewFD); 3189 } 3190 } 3191 3192 // Filter out previous declarations that don't match the scope. 3193 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3194 3195 if (isFriend) { 3196 // DC is the namespace in which the function is being declared. 3197 assert((DC->isFileContext() || !Previous.empty()) && 3198 "previously-undeclared friend function being created " 3199 "in a non-namespace context"); 3200 3201 if (FunctionTemplate) { 3202 FunctionTemplate->setObjectOfFriendDecl( 3203 /* PreviouslyDeclared= */ !Previous.empty()); 3204 FunctionTemplate->setAccess(AS_public); 3205 } 3206 else 3207 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 3208 3209 NewFD->setAccess(AS_public); 3210 } 3211 3212 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3213 !CurContext->isRecord()) { 3214 // C++ [class.static]p1: 3215 // A data or function member of a class may be declared static 3216 // in a class definition, in which case it is a static member of 3217 // the class. 3218 3219 // Complain about the 'static' specifier if it's on an out-of-line 3220 // member function definition. 3221 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3222 diag::err_static_out_of_line) 3223 << CodeModificationHint::CreateRemoval( 3224 D.getDeclSpec().getStorageClassSpecLoc()); 3225 } 3226 3227 // Handle GNU asm-label extension (encoded as an attribute). 3228 if (Expr *E = (Expr*) D.getAsmLabel()) { 3229 // The parser guarantees this is a string. 3230 StringLiteral *SE = cast<StringLiteral>(E); 3231 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 3232 } 3233 3234 // Copy the parameter declarations from the declarator D to the function 3235 // declaration NewFD, if they are available. First scavenge them into Params. 3236 llvm::SmallVector<ParmVarDecl*, 16> Params; 3237 if (D.getNumTypeObjects() > 0) { 3238 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3239 3240 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3241 // function that takes no arguments, not a function that takes a 3242 // single void argument. 3243 // We let through "const void" here because Sema::GetTypeForDeclarator 3244 // already checks for that case. 3245 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3246 FTI.ArgInfo[0].Param && 3247 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3248 // Empty arg list, don't push any params. 3249 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3250 3251 // In C++, the empty parameter-type-list must be spelled "void"; a 3252 // typedef of void is not permitted. 3253 if (getLangOptions().CPlusPlus && 3254 Param->getType().getUnqualifiedType() != Context.VoidTy) 3255 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3256 // FIXME: Leaks decl? 3257 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3258 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3259 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3260 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3261 Param->setDeclContext(NewFD); 3262 Params.push_back(Param); 3263 } 3264 } 3265 3266 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3267 // When we're declaring a function with a typedef, typeof, etc as in the 3268 // following example, we'll need to synthesize (unnamed) 3269 // parameters for use in the declaration. 3270 // 3271 // @code 3272 // typedef void fn(int); 3273 // fn f; 3274 // @endcode 3275 3276 // Synthesize a parameter for each argument type. 3277 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3278 AE = FT->arg_type_end(); AI != AE; ++AI) { 3279 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3280 SourceLocation(), 0, 3281 *AI, /*TInfo=*/0, 3282 VarDecl::None, 0); 3283 Param->setImplicit(); 3284 Params.push_back(Param); 3285 } 3286 } else { 3287 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3288 "Should not need args for typedef of non-prototype fn"); 3289 } 3290 // Finally, we know we have the right number of parameters, install them. 3291 NewFD->setParams(Context, Params.data(), Params.size()); 3292 3293 // If the declarator is a template-id, translate the parser's template 3294 // argument list into our AST format. 3295 bool HasExplicitTemplateArgs = false; 3296 TemplateArgumentListInfo TemplateArgs; 3297 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3298 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3299 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3300 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3301 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3302 TemplateId->getTemplateArgs(), 3303 TemplateId->NumArgs); 3304 translateTemplateArguments(TemplateArgsPtr, 3305 TemplateArgs); 3306 TemplateArgsPtr.release(); 3307 3308 HasExplicitTemplateArgs = true; 3309 3310 if (FunctionTemplate) { 3311 // FIXME: Diagnose function template with explicit template 3312 // arguments. 3313 HasExplicitTemplateArgs = false; 3314 } else if (!isFunctionTemplateSpecialization && 3315 !D.getDeclSpec().isFriendSpecified()) { 3316 // We have encountered something that the user meant to be a 3317 // specialization (because it has explicitly-specified template 3318 // arguments) but that was not introduced with a "template<>" (or had 3319 // too few of them). 3320 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3321 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3322 << CodeModificationHint::CreateInsertion( 3323 D.getDeclSpec().getSourceRange().getBegin(), 3324 "template<> "); 3325 isFunctionTemplateSpecialization = true; 3326 } 3327 } 3328 3329 if (isFunctionTemplateSpecialization) { 3330 if (CheckFunctionTemplateSpecialization(NewFD, 3331 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3332 Previous)) 3333 NewFD->setInvalidDecl(); 3334 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3335 CheckMemberSpecialization(NewFD, Previous)) 3336 NewFD->setInvalidDecl(); 3337 3338 // Perform semantic checking on the function declaration. 3339 bool OverloadableAttrRequired = false; // FIXME: HACK! 3340 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3341 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3342 3343 assert((NewFD->isInvalidDecl() || !Redeclaration || 3344 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3345 "previous declaration set still overloaded"); 3346 3347 // If we have a function template, check the template parameter 3348 // list. This will check and merge default template arguments. 3349 if (FunctionTemplate) { 3350 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3351 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3352 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3353 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3354 : TPC_FunctionTemplate); 3355 } 3356 3357 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3358 // An out-of-line member function declaration must also be a 3359 // definition (C++ [dcl.meaning]p1). 3360 // Note that this is not the case for explicit specializations of 3361 // function templates or member functions of class templates, per 3362 // C++ [temp.expl.spec]p2. 3363 if (!IsFunctionDefinition && !isFriend && 3364 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3365 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3366 << D.getCXXScopeSpec().getRange(); 3367 NewFD->setInvalidDecl(); 3368 } else if (!Redeclaration) { 3369 // The user tried to provide an out-of-line definition for a 3370 // function that is a member of a class or namespace, but there 3371 // was no such member function declared (C++ [class.mfct]p2, 3372 // C++ [namespace.memdef]p2). For example: 3373 // 3374 // class X { 3375 // void f() const; 3376 // }; 3377 // 3378 // void X::f() { } // ill-formed 3379 // 3380 // Complain about this problem, and attempt to suggest close 3381 // matches (e.g., those that differ only in cv-qualifiers and 3382 // whether the parameter types are references). 3383 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3384 << Name << DC << D.getCXXScopeSpec().getRange(); 3385 NewFD->setInvalidDecl(); 3386 3387 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3388 ForRedeclaration); 3389 LookupQualifiedName(Prev, DC); 3390 assert(!Prev.isAmbiguous() && 3391 "Cannot have an ambiguity in previous-declaration lookup"); 3392 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3393 Func != FuncEnd; ++Func) { 3394 if (isa<FunctionDecl>(*Func) && 3395 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3396 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3397 } 3398 } 3399 } 3400 3401 // Handle attributes. We need to have merged decls when handling attributes 3402 // (for example to check for conflicts, etc). 3403 // FIXME: This needs to happen before we merge declarations. Then, 3404 // let attribute merging cope with attribute conflicts. 3405 ProcessDeclAttributes(S, NewFD, D); 3406 3407 // attributes declared post-definition are currently ignored 3408 if (Redeclaration && Previous.isSingleResult()) { 3409 const FunctionDecl *Def; 3410 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3411 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3412 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3413 Diag(Def->getLocation(), diag::note_previous_definition); 3414 } 3415 } 3416 3417 AddKnownFunctionAttributes(NewFD); 3418 3419 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3420 // If a function name is overloadable in C, then every function 3421 // with that name must be marked "overloadable". 3422 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3423 << Redeclaration << NewFD; 3424 if (!Previous.empty()) 3425 Diag(Previous.getRepresentativeDecl()->getLocation(), 3426 diag::note_attribute_overloadable_prev_overload); 3427 NewFD->addAttr(::new (Context) OverloadableAttr()); 3428 } 3429 3430 // If this is a locally-scoped extern C function, update the 3431 // map of such names. 3432 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3433 && !NewFD->isInvalidDecl()) 3434 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3435 3436 // Set this FunctionDecl's range up to the right paren. 3437 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3438 3439 if (FunctionTemplate && NewFD->isInvalidDecl()) 3440 FunctionTemplate->setInvalidDecl(); 3441 3442 if (FunctionTemplate) 3443 return FunctionTemplate; 3444 3445 return NewFD; 3446} 3447 3448/// \brief Perform semantic checking of a new function declaration. 3449/// 3450/// Performs semantic analysis of the new function declaration 3451/// NewFD. This routine performs all semantic checking that does not 3452/// require the actual declarator involved in the declaration, and is 3453/// used both for the declaration of functions as they are parsed 3454/// (called via ActOnDeclarator) and for the declaration of functions 3455/// that have been instantiated via C++ template instantiation (called 3456/// via InstantiateDecl). 3457/// 3458/// \param IsExplicitSpecialiation whether this new function declaration is 3459/// an explicit specialization of the previous declaration. 3460/// 3461/// This sets NewFD->isInvalidDecl() to true if there was an error. 3462void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3463 LookupResult &Previous, 3464 bool IsExplicitSpecialization, 3465 bool &Redeclaration, 3466 bool &OverloadableAttrRequired) { 3467 // If NewFD is already known erroneous, don't do any of this checking. 3468 if (NewFD->isInvalidDecl()) 3469 return; 3470 3471 if (NewFD->getResultType()->isVariablyModifiedType()) { 3472 // Functions returning a variably modified type violate C99 6.7.5.2p2 3473 // because all functions have linkage. 3474 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3475 return NewFD->setInvalidDecl(); 3476 } 3477 3478 if (NewFD->isMain()) 3479 CheckMain(NewFD); 3480 3481 // Check for a previous declaration of this name. 3482 if (Previous.empty() && NewFD->isExternC()) { 3483 // Since we did not find anything by this name and we're declaring 3484 // an extern "C" function, look for a non-visible extern "C" 3485 // declaration with the same name. 3486 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3487 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3488 if (Pos != LocallyScopedExternalDecls.end()) 3489 Previous.addDecl(Pos->second); 3490 } 3491 3492 // Merge or overload the declaration with an existing declaration of 3493 // the same name, if appropriate. 3494 if (!Previous.empty()) { 3495 // Determine whether NewFD is an overload of PrevDecl or 3496 // a declaration that requires merging. If it's an overload, 3497 // there's no more work to do here; we'll just add the new 3498 // function to the scope. 3499 3500 NamedDecl *OldDecl = 0; 3501 if (!AllowOverloadingOfFunction(Previous, Context)) { 3502 Redeclaration = true; 3503 OldDecl = Previous.getFoundDecl(); 3504 } else { 3505 if (!getLangOptions().CPlusPlus) { 3506 OverloadableAttrRequired = true; 3507 3508 // Functions marked "overloadable" must have a prototype (that 3509 // we can't get through declaration merging). 3510 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3511 Diag(NewFD->getLocation(), 3512 diag::err_attribute_overloadable_no_prototype) 3513 << NewFD; 3514 Redeclaration = true; 3515 3516 // Turn this into a variadic function with no parameters. 3517 QualType R = Context.getFunctionType( 3518 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3519 0, 0, true, 0); 3520 NewFD->setType(R); 3521 return NewFD->setInvalidDecl(); 3522 } 3523 } 3524 3525 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3526 case Ovl_Match: 3527 Redeclaration = true; 3528 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3529 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3530 Redeclaration = false; 3531 } 3532 break; 3533 3534 case Ovl_NonFunction: 3535 Redeclaration = true; 3536 break; 3537 3538 case Ovl_Overload: 3539 Redeclaration = false; 3540 break; 3541 } 3542 } 3543 3544 if (Redeclaration) { 3545 // NewFD and OldDecl represent declarations that need to be 3546 // merged. 3547 if (MergeFunctionDecl(NewFD, OldDecl)) 3548 return NewFD->setInvalidDecl(); 3549 3550 Previous.clear(); 3551 Previous.addDecl(OldDecl); 3552 3553 if (FunctionTemplateDecl *OldTemplateDecl 3554 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3555 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3556 FunctionTemplateDecl *NewTemplateDecl 3557 = NewFD->getDescribedFunctionTemplate(); 3558 assert(NewTemplateDecl && "Template/non-template mismatch"); 3559 if (CXXMethodDecl *Method 3560 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3561 Method->setAccess(OldTemplateDecl->getAccess()); 3562 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3563 } 3564 3565 // If this is an explicit specialization of a member that is a function 3566 // template, mark it as a member specialization. 3567 if (IsExplicitSpecialization && 3568 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3569 NewTemplateDecl->setMemberSpecialization(); 3570 assert(OldTemplateDecl->isMemberSpecialization()); 3571 } 3572 } else { 3573 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3574 NewFD->setAccess(OldDecl->getAccess()); 3575 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3576 } 3577 } 3578 } 3579 3580 // Semantic checking for this function declaration (in isolation). 3581 if (getLangOptions().CPlusPlus) { 3582 // C++-specific checks. 3583 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3584 CheckConstructor(Constructor); 3585 } else if (CXXDestructorDecl *Destructor = 3586 dyn_cast<CXXDestructorDecl>(NewFD)) { 3587 CXXRecordDecl *Record = Destructor->getParent(); 3588 QualType ClassType = Context.getTypeDeclType(Record); 3589 3590 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3591 // type is dependent? Both gcc and edg can handle that. 3592 if (!ClassType->isDependentType()) { 3593 DeclarationName Name 3594 = Context.DeclarationNames.getCXXDestructorName( 3595 Context.getCanonicalType(ClassType)); 3596 if (NewFD->getDeclName() != Name) { 3597 Diag(NewFD->getLocation(), diag::err_destructor_name); 3598 return NewFD->setInvalidDecl(); 3599 } 3600 } 3601 3602 Record->setUserDeclaredDestructor(true); 3603 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3604 // user-defined destructor. 3605 Record->setPOD(false); 3606 3607 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3608 // declared destructor. 3609 // FIXME: C++0x: don't do this for "= default" destructors 3610 Record->setHasTrivialDestructor(false); 3611 } else if (CXXConversionDecl *Conversion 3612 = dyn_cast<CXXConversionDecl>(NewFD)) { 3613 ActOnConversionDeclarator(Conversion); 3614 } 3615 3616 // Find any virtual functions that this function overrides. 3617 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3618 if (!Method->isFunctionTemplateSpecialization() && 3619 !Method->getDescribedFunctionTemplate()) 3620 AddOverriddenMethods(Method->getParent(), Method); 3621 } 3622 3623 // Additional checks for the destructor; make sure we do this after we 3624 // figure out whether the destructor is virtual. 3625 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3626 if (!Destructor->getParent()->isDependentType()) 3627 CheckDestructor(Destructor); 3628 3629 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3630 if (NewFD->isOverloadedOperator() && 3631 CheckOverloadedOperatorDeclaration(NewFD)) 3632 return NewFD->setInvalidDecl(); 3633 3634 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3635 if (NewFD->getLiteralIdentifier() && 3636 CheckLiteralOperatorDeclaration(NewFD)) 3637 return NewFD->setInvalidDecl(); 3638 3639 // In C++, check default arguments now that we have merged decls. Unless 3640 // the lexical context is the class, because in this case this is done 3641 // during delayed parsing anyway. 3642 if (!CurContext->isRecord()) 3643 CheckCXXDefaultArguments(NewFD); 3644 } 3645} 3646 3647void Sema::CheckMain(FunctionDecl* FD) { 3648 // C++ [basic.start.main]p3: A program that declares main to be inline 3649 // or static is ill-formed. 3650 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3651 // shall not appear in a declaration of main. 3652 // static main is not an error under C99, but we should warn about it. 3653 bool isInline = FD->isInlineSpecified(); 3654 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3655 if (isInline || isStatic) { 3656 unsigned diagID = diag::warn_unusual_main_decl; 3657 if (isInline || getLangOptions().CPlusPlus) 3658 diagID = diag::err_unusual_main_decl; 3659 3660 int which = isStatic + (isInline << 1) - 1; 3661 Diag(FD->getLocation(), diagID) << which; 3662 } 3663 3664 QualType T = FD->getType(); 3665 assert(T->isFunctionType() && "function decl is not of function type"); 3666 const FunctionType* FT = T->getAs<FunctionType>(); 3667 3668 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3669 // TODO: add a replacement fixit to turn the return type into 'int'. 3670 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3671 FD->setInvalidDecl(true); 3672 } 3673 3674 // Treat protoless main() as nullary. 3675 if (isa<FunctionNoProtoType>(FT)) return; 3676 3677 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3678 unsigned nparams = FTP->getNumArgs(); 3679 assert(FD->getNumParams() == nparams); 3680 3681 bool HasExtraParameters = (nparams > 3); 3682 3683 // Darwin passes an undocumented fourth argument of type char**. If 3684 // other platforms start sprouting these, the logic below will start 3685 // getting shifty. 3686 if (nparams == 4 && 3687 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3688 HasExtraParameters = false; 3689 3690 if (HasExtraParameters) { 3691 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3692 FD->setInvalidDecl(true); 3693 nparams = 3; 3694 } 3695 3696 // FIXME: a lot of the following diagnostics would be improved 3697 // if we had some location information about types. 3698 3699 QualType CharPP = 3700 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3701 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3702 3703 for (unsigned i = 0; i < nparams; ++i) { 3704 QualType AT = FTP->getArgType(i); 3705 3706 bool mismatch = true; 3707 3708 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3709 mismatch = false; 3710 else if (Expected[i] == CharPP) { 3711 // As an extension, the following forms are okay: 3712 // char const ** 3713 // char const * const * 3714 // char * const * 3715 3716 QualifierCollector qs; 3717 const PointerType* PT; 3718 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3719 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3720 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3721 qs.removeConst(); 3722 mismatch = !qs.empty(); 3723 } 3724 } 3725 3726 if (mismatch) { 3727 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3728 // TODO: suggest replacing given type with expected type 3729 FD->setInvalidDecl(true); 3730 } 3731 } 3732 3733 if (nparams == 1 && !FD->isInvalidDecl()) { 3734 Diag(FD->getLocation(), diag::warn_main_one_arg); 3735 } 3736} 3737 3738bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3739 // FIXME: Need strict checking. In C89, we need to check for 3740 // any assignment, increment, decrement, function-calls, or 3741 // commas outside of a sizeof. In C99, it's the same list, 3742 // except that the aforementioned are allowed in unevaluated 3743 // expressions. Everything else falls under the 3744 // "may accept other forms of constant expressions" exception. 3745 // (We never end up here for C++, so the constant expression 3746 // rules there don't matter.) 3747 if (Init->isConstantInitializer(Context)) 3748 return false; 3749 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3750 << Init->getSourceRange(); 3751 return true; 3752} 3753 3754void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3755 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3756} 3757 3758/// AddInitializerToDecl - Adds the initializer Init to the 3759/// declaration dcl. If DirectInit is true, this is C++ direct 3760/// initialization rather than copy initialization. 3761void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3762 Decl *RealDecl = dcl.getAs<Decl>(); 3763 // If there is no declaration, there was an error parsing it. Just ignore 3764 // the initializer. 3765 if (RealDecl == 0) 3766 return; 3767 3768 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3769 // With declarators parsed the way they are, the parser cannot 3770 // distinguish between a normal initializer and a pure-specifier. 3771 // Thus this grotesque test. 3772 IntegerLiteral *IL; 3773 Expr *Init = static_cast<Expr *>(init.get()); 3774 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3775 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3776 CheckPureMethod(Method, Init->getSourceRange()); 3777 else { 3778 Diag(Method->getLocation(), diag::err_member_function_initialization) 3779 << Method->getDeclName() << Init->getSourceRange(); 3780 Method->setInvalidDecl(); 3781 } 3782 return; 3783 } 3784 3785 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3786 if (!VDecl) { 3787 if (getLangOptions().CPlusPlus && 3788 RealDecl->getLexicalDeclContext()->isRecord() && 3789 isa<NamedDecl>(RealDecl)) 3790 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3791 << cast<NamedDecl>(RealDecl)->getDeclName(); 3792 else 3793 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3794 RealDecl->setInvalidDecl(); 3795 return; 3796 } 3797 3798 // A definition must end up with a complete type, which means it must be 3799 // complete with the restriction that an array type might be completed by the 3800 // initializer; note that later code assumes this restriction. 3801 QualType BaseDeclType = VDecl->getType(); 3802 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3803 BaseDeclType = Array->getElementType(); 3804 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3805 diag::err_typecheck_decl_incomplete_type)) { 3806 RealDecl->setInvalidDecl(); 3807 return; 3808 } 3809 3810 // The variable can not have an abstract class type. 3811 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3812 diag::err_abstract_type_in_decl, 3813 AbstractVariableType)) 3814 VDecl->setInvalidDecl(); 3815 3816 const VarDecl *Def = 0; 3817 if (VDecl->getDefinition(Def)) { 3818 Diag(VDecl->getLocation(), diag::err_redefinition) 3819 << VDecl->getDeclName(); 3820 Diag(Def->getLocation(), diag::note_previous_definition); 3821 VDecl->setInvalidDecl(); 3822 return; 3823 } 3824 3825 // Take ownership of the expression, now that we're sure we have somewhere 3826 // to put it. 3827 Expr *Init = init.takeAs<Expr>(); 3828 assert(Init && "missing initializer"); 3829 3830 // Capture the variable that is being initialized and the style of 3831 // initialization. 3832 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3833 3834 // FIXME: Poor source location information. 3835 InitializationKind Kind 3836 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3837 Init->getLocStart(), 3838 Init->getLocEnd()) 3839 : InitializationKind::CreateCopy(VDecl->getLocation(), 3840 Init->getLocStart()); 3841 3842 // Get the decls type and save a reference for later, since 3843 // CheckInitializerTypes may change it. 3844 QualType DclT = VDecl->getType(), SavT = DclT; 3845 if (VDecl->isBlockVarDecl()) { 3846 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3847 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3848 VDecl->setInvalidDecl(); 3849 } else if (!VDecl->isInvalidDecl()) { 3850 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3851 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3852 MultiExprArg(*this, (void**)&Init, 1), 3853 &DclT); 3854 if (Result.isInvalid()) { 3855 VDecl->setInvalidDecl(); 3856 return; 3857 } 3858 3859 Init = Result.takeAs<Expr>(); 3860 3861 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3862 // Don't check invalid declarations to avoid emitting useless diagnostics. 3863 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3864 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3865 CheckForConstantInitializer(Init, DclT); 3866 } 3867 } 3868 } else if (VDecl->isStaticDataMember() && 3869 VDecl->getLexicalDeclContext()->isRecord()) { 3870 // This is an in-class initialization for a static data member, e.g., 3871 // 3872 // struct S { 3873 // static const int value = 17; 3874 // }; 3875 3876 // Attach the initializer 3877 VDecl->setInit(Context, Init); 3878 3879 // C++ [class.mem]p4: 3880 // A member-declarator can contain a constant-initializer only 3881 // if it declares a static member (9.4) of const integral or 3882 // const enumeration type, see 9.4.2. 3883 QualType T = VDecl->getType(); 3884 if (!T->isDependentType() && 3885 (!Context.getCanonicalType(T).isConstQualified() || 3886 !T->isIntegralType())) { 3887 Diag(VDecl->getLocation(), diag::err_member_initialization) 3888 << VDecl->getDeclName() << Init->getSourceRange(); 3889 VDecl->setInvalidDecl(); 3890 } else { 3891 // C++ [class.static.data]p4: 3892 // If a static data member is of const integral or const 3893 // enumeration type, its declaration in the class definition 3894 // can specify a constant-initializer which shall be an 3895 // integral constant expression (5.19). 3896 if (!Init->isTypeDependent() && 3897 !Init->getType()->isIntegralType()) { 3898 // We have a non-dependent, non-integral or enumeration type. 3899 Diag(Init->getSourceRange().getBegin(), 3900 diag::err_in_class_initializer_non_integral_type) 3901 << Init->getType() << Init->getSourceRange(); 3902 VDecl->setInvalidDecl(); 3903 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3904 // Check whether the expression is a constant expression. 3905 llvm::APSInt Value; 3906 SourceLocation Loc; 3907 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3908 Diag(Loc, diag::err_in_class_initializer_non_constant) 3909 << Init->getSourceRange(); 3910 VDecl->setInvalidDecl(); 3911 } else if (!VDecl->getType()->isDependentType()) 3912 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3913 } 3914 } 3915 } else if (VDecl->isFileVarDecl()) { 3916 if (VDecl->getStorageClass() == VarDecl::Extern) 3917 Diag(VDecl->getLocation(), diag::warn_extern_init); 3918 if (!VDecl->isInvalidDecl()) { 3919 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3920 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3921 MultiExprArg(*this, (void**)&Init, 1), 3922 &DclT); 3923 if (Result.isInvalid()) { 3924 VDecl->setInvalidDecl(); 3925 return; 3926 } 3927 3928 Init = Result.takeAs<Expr>(); 3929 } 3930 3931 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3932 // Don't check invalid declarations to avoid emitting useless diagnostics. 3933 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3934 // C99 6.7.8p4. All file scoped initializers need to be constant. 3935 CheckForConstantInitializer(Init, DclT); 3936 } 3937 } 3938 // If the type changed, it means we had an incomplete type that was 3939 // completed by the initializer. For example: 3940 // int ary[] = { 1, 3, 5 }; 3941 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3942 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3943 VDecl->setType(DclT); 3944 Init->setType(DclT); 3945 } 3946 3947 Init = MaybeCreateCXXExprWithTemporaries(Init); 3948 // Attach the initializer to the decl. 3949 VDecl->setInit(Context, Init); 3950 3951 // If the previous declaration of VDecl was a tentative definition, 3952 // remove it from the set of tentative definitions. 3953 if (VDecl->getPreviousDeclaration() && 3954 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3955 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3956 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3957 } 3958 3959 if (getLangOptions().CPlusPlus) { 3960 // Make sure we mark the destructor as used if necessary. 3961 QualType InitType = VDecl->getType(); 3962 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3963 InitType = Context.getBaseElementType(Array); 3964 if (InitType->isRecordType()) 3965 FinalizeVarWithDestructor(VDecl, InitType); 3966 } 3967 3968 return; 3969} 3970 3971void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3972 bool TypeContainsUndeducedAuto) { 3973 Decl *RealDecl = dcl.getAs<Decl>(); 3974 3975 // If there is no declaration, there was an error parsing it. Just ignore it. 3976 if (RealDecl == 0) 3977 return; 3978 3979 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3980 QualType Type = Var->getType(); 3981 3982 // Record tentative definitions. 3983 if (Var->isTentativeDefinition(Context)) { 3984 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3985 InsertPair = 3986 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3987 3988 // Keep the latest definition in the map. If we see 'int i; int i;' we 3989 // want the second one in the map. 3990 InsertPair.first->second = Var; 3991 3992 // However, for the list, we don't care about the order, just make sure 3993 // that there are no dupes for a given declaration name. 3994 if (InsertPair.second) 3995 TentativeDefinitionList.push_back(Var->getDeclName()); 3996 } 3997 3998 // C++ [dcl.init.ref]p3: 3999 // The initializer can be omitted for a reference only in a 4000 // parameter declaration (8.3.5), in the declaration of a 4001 // function return type, in the declaration of a class member 4002 // within its class declaration (9.2), and where the extern 4003 // specifier is explicitly used. 4004 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 4005 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4006 << Var->getDeclName() 4007 << SourceRange(Var->getLocation(), Var->getLocation()); 4008 Var->setInvalidDecl(); 4009 return; 4010 } 4011 4012 // C++0x [dcl.spec.auto]p3 4013 if (TypeContainsUndeducedAuto) { 4014 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4015 << Var->getDeclName() << Type; 4016 Var->setInvalidDecl(); 4017 return; 4018 } 4019 4020 // An array without size is an incomplete type, and there are no special 4021 // rules in C++ to make such a definition acceptable. 4022 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 4023 !Var->hasExternalStorage()) { 4024 Diag(Var->getLocation(), 4025 diag::err_typecheck_incomplete_array_needs_initializer); 4026 Var->setInvalidDecl(); 4027 return; 4028 } 4029 4030 // C++ [temp.expl.spec]p15: 4031 // An explicit specialization of a static data member of a template is a 4032 // definition if the declaration includes an initializer; otherwise, it 4033 // is a declaration. 4034 if (Var->isStaticDataMember() && 4035 Var->getInstantiatedFromStaticDataMember() && 4036 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 4037 return; 4038 4039 // C++ [dcl.init]p9: 4040 // If no initializer is specified for an object, and the object 4041 // is of (possibly cv-qualified) non-POD class type (or array 4042 // thereof), the object shall be default-initialized; if the 4043 // object is of const-qualified type, the underlying class type 4044 // shall have a user-declared default constructor. 4045 // 4046 // FIXME: Diagnose the "user-declared default constructor" bit. 4047 if (getLangOptions().CPlusPlus) { 4048 QualType InitType = Type; 4049 if (const ArrayType *Array = Context.getAsArrayType(Type)) 4050 InitType = Context.getBaseElementType(Array); 4051 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 4052 InitType->isRecordType() && !InitType->isDependentType()) { 4053 if (!RequireCompleteType(Var->getLocation(), InitType, 4054 diag::err_invalid_incomplete_type_use)) { 4055 InitializedEntity Entity 4056 = InitializedEntity::InitializeVariable(Var); 4057 InitializationKind Kind 4058 = InitializationKind::CreateDefault(Var->getLocation()); 4059 4060 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4061 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4062 MultiExprArg(*this, 0, 0)); 4063 if (Init.isInvalid()) 4064 Var->setInvalidDecl(); 4065 else { 4066 Var->setInit(Context, 4067 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4068 FinalizeVarWithDestructor(Var, InitType); 4069 } 4070 } else { 4071 Var->setInvalidDecl(); 4072 } 4073 } 4074 4075 // The variable can not have an abstract class type. 4076 if (RequireNonAbstractType(Var->getLocation(), Type, 4077 diag::err_abstract_type_in_decl, 4078 AbstractVariableType)) 4079 Var->setInvalidDecl(); 4080 } 4081 4082#if 0 4083 // FIXME: Temporarily disabled because we are not properly parsing 4084 // linkage specifications on declarations, e.g., 4085 // 4086 // extern "C" const CGPoint CGPointerZero; 4087 // 4088 // C++ [dcl.init]p9: 4089 // 4090 // If no initializer is specified for an object, and the 4091 // object is of (possibly cv-qualified) non-POD class type (or 4092 // array thereof), the object shall be default-initialized; if 4093 // the object is of const-qualified type, the underlying class 4094 // type shall have a user-declared default 4095 // constructor. Otherwise, if no initializer is specified for 4096 // an object, the object and its subobjects, if any, have an 4097 // indeterminate initial value; if the object or any of its 4098 // subobjects are of const-qualified type, the program is 4099 // ill-formed. 4100 // 4101 // This isn't technically an error in C, so we don't diagnose it. 4102 // 4103 // FIXME: Actually perform the POD/user-defined default 4104 // constructor check. 4105 if (getLangOptions().CPlusPlus && 4106 Context.getCanonicalType(Type).isConstQualified() && 4107 !Var->hasExternalStorage()) 4108 Diag(Var->getLocation(), diag::err_const_var_requires_init) 4109 << Var->getName() 4110 << SourceRange(Var->getLocation(), Var->getLocation()); 4111#endif 4112 } 4113} 4114 4115Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4116 DeclPtrTy *Group, 4117 unsigned NumDecls) { 4118 llvm::SmallVector<Decl*, 8> Decls; 4119 4120 if (DS.isTypeSpecOwned()) 4121 Decls.push_back((Decl*)DS.getTypeRep()); 4122 4123 for (unsigned i = 0; i != NumDecls; ++i) 4124 if (Decl *D = Group[i].getAs<Decl>()) 4125 Decls.push_back(D); 4126 4127 // Perform semantic analysis that depends on having fully processed both 4128 // the declarator and initializer. 4129 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 4130 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 4131 if (!IDecl) 4132 continue; 4133 QualType T = IDecl->getType(); 4134 4135 // Block scope. C99 6.7p7: If an identifier for an object is declared with 4136 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 4137 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 4138 if (T->isDependentType()) { 4139 // If T is dependent, we should not require a complete type. 4140 // (RequireCompleteType shouldn't be called with dependent types.) 4141 // But we still can at least check if we've got an array of unspecified 4142 // size without an initializer. 4143 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 4144 !IDecl->getInit()) { 4145 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 4146 << T; 4147 IDecl->setInvalidDecl(); 4148 } 4149 } else if (!IDecl->isInvalidDecl()) { 4150 // If T is an incomplete array type with an initializer list that is 4151 // dependent on something, its size has not been fixed. We could attempt 4152 // to fix the size for such arrays, but we would still have to check 4153 // here for initializers containing a C++0x vararg expansion, e.g. 4154 // template <typename... Args> void f(Args... args) { 4155 // int vals[] = { args }; 4156 // } 4157 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 4158 Expr *Init = IDecl->getInit(); 4159 if (IAT && Init && 4160 (Init->isTypeDependent() || Init->isValueDependent())) { 4161 // Check that the member type of the array is complete, at least. 4162 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 4163 diag::err_typecheck_decl_incomplete_type)) 4164 IDecl->setInvalidDecl(); 4165 } else if (RequireCompleteType(IDecl->getLocation(), T, 4166 diag::err_typecheck_decl_incomplete_type)) 4167 IDecl->setInvalidDecl(); 4168 } 4169 } 4170 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4171 // object that has file scope without an initializer, and without a 4172 // storage-class specifier or with the storage-class specifier "static", 4173 // constitutes a tentative definition. Note: A tentative definition with 4174 // external linkage is valid (C99 6.2.2p5). 4175 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 4176 if (const IncompleteArrayType *ArrayT 4177 = Context.getAsIncompleteArrayType(T)) { 4178 if (RequireCompleteType(IDecl->getLocation(), 4179 ArrayT->getElementType(), 4180 diag::err_illegal_decl_array_incomplete_type)) 4181 IDecl->setInvalidDecl(); 4182 } else if (IDecl->getStorageClass() == VarDecl::Static) { 4183 // C99 6.9.2p3: If the declaration of an identifier for an object is 4184 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4185 // declared type shall not be an incomplete type. 4186 // NOTE: code such as the following 4187 // static struct s; 4188 // struct s { int a; }; 4189 // is accepted by gcc. Hence here we issue a warning instead of 4190 // an error and we do not invalidate the static declaration. 4191 // NOTE: to avoid multiple warnings, only check the first declaration. 4192 if (IDecl->getPreviousDeclaration() == 0) 4193 RequireCompleteType(IDecl->getLocation(), T, 4194 diag::ext_typecheck_decl_incomplete_type); 4195 } 4196 } 4197 } 4198 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4199 Decls.data(), Decls.size())); 4200} 4201 4202 4203/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4204/// to introduce parameters into function prototype scope. 4205Sema::DeclPtrTy 4206Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4207 const DeclSpec &DS = D.getDeclSpec(); 4208 4209 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4210 VarDecl::StorageClass StorageClass = VarDecl::None; 4211 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4212 StorageClass = VarDecl::Register; 4213 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4214 Diag(DS.getStorageClassSpecLoc(), 4215 diag::err_invalid_storage_class_in_func_decl); 4216 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4217 } 4218 4219 if (D.getDeclSpec().isThreadSpecified()) 4220 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4221 4222 DiagnoseFunctionSpecifiers(D); 4223 4224 // Check that there are no default arguments inside the type of this 4225 // parameter (C++ only). 4226 if (getLangOptions().CPlusPlus) 4227 CheckExtraCXXDefaultArguments(D); 4228 4229 TypeSourceInfo *TInfo = 0; 4230 TagDecl *OwnedDecl = 0; 4231 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4232 4233 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4234 // C++ [dcl.fct]p6: 4235 // Types shall not be defined in return or parameter types. 4236 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4237 << Context.getTypeDeclType(OwnedDecl); 4238 } 4239 4240 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 4241 // Can this happen for params? We already checked that they don't conflict 4242 // among each other. Here they can only shadow globals, which is ok. 4243 IdentifierInfo *II = D.getIdentifier(); 4244 if (II) { 4245 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 4246 if (PrevDecl->isTemplateParameter()) { 4247 // Maybe we will complain about the shadowed template parameter. 4248 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4249 // Just pretend that we didn't see the previous declaration. 4250 PrevDecl = 0; 4251 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4252 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4253 4254 // Recover by removing the name 4255 II = 0; 4256 D.SetIdentifier(0, D.getIdentifierLoc()); 4257 } 4258 } 4259 } 4260 4261 // Parameters can not be abstract class types. 4262 // For record types, this is done by the AbstractClassUsageDiagnoser once 4263 // the class has been completely parsed. 4264 if (!CurContext->isRecord() && 4265 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4266 diag::err_abstract_type_in_decl, 4267 AbstractParamType)) 4268 D.setInvalidType(true); 4269 4270 QualType T = adjustParameterType(parmDeclType); 4271 4272 ParmVarDecl *New 4273 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 4274 T, TInfo, StorageClass, 0); 4275 4276 if (D.isInvalidType()) 4277 New->setInvalidDecl(); 4278 4279 // Parameter declarators cannot be interface types. All ObjC objects are 4280 // passed by reference. 4281 if (T->isObjCInterfaceType()) { 4282 Diag(D.getIdentifierLoc(), 4283 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4284 New->setInvalidDecl(); 4285 } 4286 4287 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4288 if (D.getCXXScopeSpec().isSet()) { 4289 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4290 << D.getCXXScopeSpec().getRange(); 4291 New->setInvalidDecl(); 4292 } 4293 4294 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4295 // duration shall not be qualified by an address-space qualifier." 4296 // Since all parameters have automatic store duration, they can not have 4297 // an address space. 4298 if (T.getAddressSpace() != 0) { 4299 Diag(D.getIdentifierLoc(), 4300 diag::err_arg_with_address_space); 4301 New->setInvalidDecl(); 4302 } 4303 4304 4305 // Add the parameter declaration into this scope. 4306 S->AddDecl(DeclPtrTy::make(New)); 4307 if (II) 4308 IdResolver.AddDecl(New); 4309 4310 ProcessDeclAttributes(S, New, D); 4311 4312 if (New->hasAttr<BlocksAttr>()) { 4313 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4314 } 4315 return DeclPtrTy::make(New); 4316} 4317 4318void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4319 SourceLocation LocAfterDecls) { 4320 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4321 "Not a function declarator!"); 4322 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4323 4324 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4325 // for a K&R function. 4326 if (!FTI.hasPrototype) { 4327 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4328 --i; 4329 if (FTI.ArgInfo[i].Param == 0) { 4330 llvm::SmallString<256> Code; 4331 llvm::raw_svector_ostream(Code) << " int " 4332 << FTI.ArgInfo[i].Ident->getName() 4333 << ";\n"; 4334 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4335 << FTI.ArgInfo[i].Ident 4336 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4337 4338 // Implicitly declare the argument as type 'int' for lack of a better 4339 // type. 4340 DeclSpec DS; 4341 const char* PrevSpec; // unused 4342 unsigned DiagID; // unused 4343 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4344 PrevSpec, DiagID); 4345 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4346 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4347 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4348 } 4349 } 4350 } 4351} 4352 4353Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4354 Declarator &D) { 4355 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4356 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4357 "Not a function declarator!"); 4358 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4359 4360 if (FTI.hasPrototype) { 4361 // FIXME: Diagnose arguments without names in C. 4362 } 4363 4364 Scope *ParentScope = FnBodyScope->getParent(); 4365 4366 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4367 MultiTemplateParamsArg(*this), 4368 /*IsFunctionDefinition=*/true); 4369 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4370} 4371 4372static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4373 // Don't warn about invalid declarations. 4374 if (FD->isInvalidDecl()) 4375 return false; 4376 4377 // Or declarations that aren't global. 4378 if (!FD->isGlobal()) 4379 return false; 4380 4381 // Don't warn about C++ member functions. 4382 if (isa<CXXMethodDecl>(FD)) 4383 return false; 4384 4385 // Don't warn about 'main'. 4386 if (FD->isMain()) 4387 return false; 4388 4389 // Don't warn about inline functions. 4390 if (FD->isInlineSpecified()) 4391 return false; 4392 4393 // Don't warn about function templates. 4394 if (FD->getDescribedFunctionTemplate()) 4395 return false; 4396 4397 // Don't warn about function template specializations. 4398 if (FD->isFunctionTemplateSpecialization()) 4399 return false; 4400 4401 bool MissingPrototype = true; 4402 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4403 Prev; Prev = Prev->getPreviousDeclaration()) { 4404 // Ignore any declarations that occur in function or method 4405 // scope, because they aren't visible from the header. 4406 if (Prev->getDeclContext()->isFunctionOrMethod()) 4407 continue; 4408 4409 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4410 break; 4411 } 4412 4413 return MissingPrototype; 4414} 4415 4416Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4417 // Clear the last template instantiation error context. 4418 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4419 4420 if (!D) 4421 return D; 4422 FunctionDecl *FD = 0; 4423 4424 if (FunctionTemplateDecl *FunTmpl 4425 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4426 FD = FunTmpl->getTemplatedDecl(); 4427 else 4428 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4429 4430 CurFunctionNeedsScopeChecking = false; 4431 4432 // See if this is a redefinition. 4433 const FunctionDecl *Definition; 4434 if (FD->getBody(Definition)) { 4435 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4436 Diag(Definition->getLocation(), diag::note_previous_definition); 4437 } 4438 4439 // Builtin functions cannot be defined. 4440 if (unsigned BuiltinID = FD->getBuiltinID()) { 4441 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4442 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4443 FD->setInvalidDecl(); 4444 } 4445 } 4446 4447 // The return type of a function definition must be complete 4448 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4449 QualType ResultType = FD->getResultType(); 4450 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4451 !FD->isInvalidDecl() && 4452 RequireCompleteType(FD->getLocation(), ResultType, 4453 diag::err_func_def_incomplete_result)) 4454 FD->setInvalidDecl(); 4455 4456 // GNU warning -Wmissing-prototypes: 4457 // Warn if a global function is defined without a previous 4458 // prototype declaration. This warning is issued even if the 4459 // definition itself provides a prototype. The aim is to detect 4460 // global functions that fail to be declared in header files. 4461 if (ShouldWarnAboutMissingPrototype(FD)) 4462 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4463 4464 if (FnBodyScope) 4465 PushDeclContext(FnBodyScope, FD); 4466 4467 // Check the validity of our function parameters 4468 CheckParmsForFunctionDef(FD); 4469 4470 // Introduce our parameters into the function scope 4471 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4472 ParmVarDecl *Param = FD->getParamDecl(p); 4473 Param->setOwningFunction(FD); 4474 4475 // If this has an identifier, add it to the scope stack. 4476 if (Param->getIdentifier() && FnBodyScope) 4477 PushOnScopeChains(Param, FnBodyScope); 4478 } 4479 4480 // Checking attributes of current function definition 4481 // dllimport attribute. 4482 if (FD->getAttr<DLLImportAttr>() && 4483 (!FD->getAttr<DLLExportAttr>())) { 4484 // dllimport attribute cannot be applied to definition. 4485 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4486 Diag(FD->getLocation(), 4487 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4488 << "dllimport"; 4489 FD->setInvalidDecl(); 4490 return DeclPtrTy::make(FD); 4491 } else { 4492 // If a symbol previously declared dllimport is later defined, the 4493 // attribute is ignored in subsequent references, and a warning is 4494 // emitted. 4495 Diag(FD->getLocation(), 4496 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4497 << FD->getNameAsCString() << "dllimport"; 4498 } 4499 } 4500 return DeclPtrTy::make(FD); 4501} 4502 4503Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4504 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4505} 4506 4507Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4508 bool IsInstantiation) { 4509 Decl *dcl = D.getAs<Decl>(); 4510 Stmt *Body = BodyArg.takeAs<Stmt>(); 4511 4512 AnalysisContext AC(dcl); 4513 FunctionDecl *FD = 0; 4514 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4515 if (FunTmpl) 4516 FD = FunTmpl->getTemplatedDecl(); 4517 else 4518 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4519 4520 if (FD) { 4521 FD->setBody(Body); 4522 if (FD->isMain()) 4523 // C and C++ allow for main to automagically return 0. 4524 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4525 FD->setHasImplicitReturnZero(true); 4526 else 4527 CheckFallThroughForFunctionDef(FD, Body, AC); 4528 4529 if (!FD->isInvalidDecl()) 4530 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4531 4532 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4533 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4534 4535 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4536 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4537 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4538 MD->setBody(Body); 4539 CheckFallThroughForFunctionDef(MD, Body, AC); 4540 MD->setEndLoc(Body->getLocEnd()); 4541 4542 if (!MD->isInvalidDecl()) 4543 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4544 } else { 4545 Body->Destroy(Context); 4546 return DeclPtrTy(); 4547 } 4548 if (!IsInstantiation) 4549 PopDeclContext(); 4550 4551 // Verify and clean out per-function state. 4552 4553 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4554 4555 // Check goto/label use. 4556 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4557 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4558 LabelStmt *L = I->second; 4559 4560 // Verify that we have no forward references left. If so, there was a goto 4561 // or address of a label taken, but no definition of it. Label fwd 4562 // definitions are indicated with a null substmt. 4563 if (L->getSubStmt() != 0) 4564 continue; 4565 4566 // Emit error. 4567 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4568 4569 // At this point, we have gotos that use the bogus label. Stitch it into 4570 // the function body so that they aren't leaked and that the AST is well 4571 // formed. 4572 if (Body == 0) { 4573 // The whole function wasn't parsed correctly, just delete this. 4574 L->Destroy(Context); 4575 continue; 4576 } 4577 4578 // Otherwise, the body is valid: we want to stitch the label decl into the 4579 // function somewhere so that it is properly owned and so that the goto 4580 // has a valid target. Do this by creating a new compound stmt with the 4581 // label in it. 4582 4583 // Give the label a sub-statement. 4584 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4585 4586 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4587 cast<CXXTryStmt>(Body)->getTryBlock() : 4588 cast<CompoundStmt>(Body); 4589 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4590 Elements.push_back(L); 4591 Compound->setStmts(Context, &Elements[0], Elements.size()); 4592 } 4593 FunctionLabelMap.clear(); 4594 4595 if (!Body) return D; 4596 4597 CheckUnreachable(AC); 4598 4599 // Verify that that gotos and switch cases don't jump into scopes illegally. 4600 if (CurFunctionNeedsScopeChecking) 4601 DiagnoseInvalidJumps(Body); 4602 4603 // C++ constructors that have function-try-blocks can't have return 4604 // statements in the handlers of that block. (C++ [except.handle]p14) 4605 // Verify this. 4606 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4607 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4608 4609 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4610 MarkBaseAndMemberDestructorsReferenced(Destructor); 4611 4612 // If any errors have occurred, clear out any temporaries that may have 4613 // been leftover. This ensures that these temporaries won't be picked up for 4614 // deletion in some later function. 4615 if (PP.getDiagnostics().hasErrorOccurred()) 4616 ExprTemporaries.clear(); 4617 4618 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4619 return D; 4620} 4621 4622/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4623/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4624NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4625 IdentifierInfo &II, Scope *S) { 4626 // Before we produce a declaration for an implicitly defined 4627 // function, see whether there was a locally-scoped declaration of 4628 // this name as a function or variable. If so, use that 4629 // (non-visible) declaration, and complain about it. 4630 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4631 = LocallyScopedExternalDecls.find(&II); 4632 if (Pos != LocallyScopedExternalDecls.end()) { 4633 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4634 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4635 return Pos->second; 4636 } 4637 4638 // Extension in C99. Legal in C90, but warn about it. 4639 if (II.getName().startswith("__builtin_")) 4640 Diag(Loc, diag::warn_builtin_unknown) << &II; 4641 else if (getLangOptions().C99) 4642 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4643 else 4644 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4645 4646 // Set a Declarator for the implicit definition: int foo(); 4647 const char *Dummy; 4648 DeclSpec DS; 4649 unsigned DiagID; 4650 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4651 Error = Error; // Silence warning. 4652 assert(!Error && "Error setting up implicit decl!"); 4653 Declarator D(DS, Declarator::BlockContext); 4654 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4655 0, 0, false, SourceLocation(), 4656 false, 0,0,0, Loc, Loc, D), 4657 SourceLocation()); 4658 D.SetIdentifier(&II, Loc); 4659 4660 // Insert this function into translation-unit scope. 4661 4662 DeclContext *PrevDC = CurContext; 4663 CurContext = Context.getTranslationUnitDecl(); 4664 4665 FunctionDecl *FD = 4666 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4667 FD->setImplicit(); 4668 4669 CurContext = PrevDC; 4670 4671 AddKnownFunctionAttributes(FD); 4672 4673 return FD; 4674} 4675 4676/// \brief Adds any function attributes that we know a priori based on 4677/// the declaration of this function. 4678/// 4679/// These attributes can apply both to implicitly-declared builtins 4680/// (like __builtin___printf_chk) or to library-declared functions 4681/// like NSLog or printf. 4682void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4683 if (FD->isInvalidDecl()) 4684 return; 4685 4686 // If this is a built-in function, map its builtin attributes to 4687 // actual attributes. 4688 if (unsigned BuiltinID = FD->getBuiltinID()) { 4689 // Handle printf-formatting attributes. 4690 unsigned FormatIdx; 4691 bool HasVAListArg; 4692 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4693 if (!FD->getAttr<FormatAttr>()) 4694 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4695 HasVAListArg ? 0 : FormatIdx + 2)); 4696 } 4697 4698 // Mark const if we don't care about errno and that is the only 4699 // thing preventing the function from being const. This allows 4700 // IRgen to use LLVM intrinsics for such functions. 4701 if (!getLangOptions().MathErrno && 4702 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4703 if (!FD->getAttr<ConstAttr>()) 4704 FD->addAttr(::new (Context) ConstAttr()); 4705 } 4706 4707 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4708 FD->addAttr(::new (Context) NoReturnAttr()); 4709 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4710 FD->addAttr(::new (Context) NoThrowAttr()); 4711 if (Context.BuiltinInfo.isConst(BuiltinID)) 4712 FD->addAttr(::new (Context) ConstAttr()); 4713 } 4714 4715 IdentifierInfo *Name = FD->getIdentifier(); 4716 if (!Name) 4717 return; 4718 if ((!getLangOptions().CPlusPlus && 4719 FD->getDeclContext()->isTranslationUnit()) || 4720 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4721 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4722 LinkageSpecDecl::lang_c)) { 4723 // Okay: this could be a libc/libm/Objective-C function we know 4724 // about. 4725 } else 4726 return; 4727 4728 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4729 // FIXME: NSLog and NSLogv should be target specific 4730 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4731 // FIXME: We known better than our headers. 4732 const_cast<FormatAttr *>(Format)->setType("printf"); 4733 } else 4734 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4735 Name->isStr("NSLogv") ? 0 : 2)); 4736 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4737 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4738 // target-specific builtins, perhaps? 4739 if (!FD->getAttr<FormatAttr>()) 4740 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4741 Name->isStr("vasprintf") ? 0 : 3)); 4742 } 4743} 4744 4745TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4746 TypeSourceInfo *TInfo) { 4747 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4748 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4749 4750 if (!TInfo) { 4751 assert(D.isInvalidType() && "no declarator info for valid type"); 4752 TInfo = Context.getTrivialTypeSourceInfo(T); 4753 } 4754 4755 // Scope manipulation handled by caller. 4756 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4757 D.getIdentifierLoc(), 4758 D.getIdentifier(), 4759 TInfo); 4760 4761 if (const TagType *TT = T->getAs<TagType>()) { 4762 TagDecl *TD = TT->getDecl(); 4763 4764 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4765 // keep track of the TypedefDecl. 4766 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4767 TD->setTypedefForAnonDecl(NewTD); 4768 } 4769 4770 if (D.isInvalidType()) 4771 NewTD->setInvalidDecl(); 4772 return NewTD; 4773} 4774 4775 4776/// \brief Determine whether a tag with a given kind is acceptable 4777/// as a redeclaration of the given tag declaration. 4778/// 4779/// \returns true if the new tag kind is acceptable, false otherwise. 4780bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4781 TagDecl::TagKind NewTag, 4782 SourceLocation NewTagLoc, 4783 const IdentifierInfo &Name) { 4784 // C++ [dcl.type.elab]p3: 4785 // The class-key or enum keyword present in the 4786 // elaborated-type-specifier shall agree in kind with the 4787 // declaration to which the name in theelaborated-type-specifier 4788 // refers. This rule also applies to the form of 4789 // elaborated-type-specifier that declares a class-name or 4790 // friend class since it can be construed as referring to the 4791 // definition of the class. Thus, in any 4792 // elaborated-type-specifier, the enum keyword shall be used to 4793 // refer to an enumeration (7.2), the union class-keyshall be 4794 // used to refer to a union (clause 9), and either the class or 4795 // struct class-key shall be used to refer to a class (clause 9) 4796 // declared using the class or struct class-key. 4797 TagDecl::TagKind OldTag = Previous->getTagKind(); 4798 if (OldTag == NewTag) 4799 return true; 4800 4801 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4802 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4803 // Warn about the struct/class tag mismatch. 4804 bool isTemplate = false; 4805 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4806 isTemplate = Record->getDescribedClassTemplate(); 4807 4808 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4809 << (NewTag == TagDecl::TK_class) 4810 << isTemplate << &Name 4811 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4812 OldTag == TagDecl::TK_class? "class" : "struct"); 4813 Diag(Previous->getLocation(), diag::note_previous_use); 4814 return true; 4815 } 4816 return false; 4817} 4818 4819/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4820/// former case, Name will be non-null. In the later case, Name will be null. 4821/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4822/// reference/declaration/definition of a tag. 4823Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4824 SourceLocation KWLoc, const CXXScopeSpec &SS, 4825 IdentifierInfo *Name, SourceLocation NameLoc, 4826 AttributeList *Attr, AccessSpecifier AS, 4827 MultiTemplateParamsArg TemplateParameterLists, 4828 bool &OwnedDecl, bool &IsDependent) { 4829 // If this is not a definition, it must have a name. 4830 assert((Name != 0 || TUK == TUK_Definition) && 4831 "Nameless record must be a definition!"); 4832 4833 OwnedDecl = false; 4834 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4835 4836 // FIXME: Check explicit specializations more carefully. 4837 bool isExplicitSpecialization = false; 4838 if (TUK != TUK_Reference) { 4839 if (TemplateParameterList *TemplateParams 4840 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4841 (TemplateParameterList**)TemplateParameterLists.get(), 4842 TemplateParameterLists.size(), 4843 isExplicitSpecialization)) { 4844 if (TemplateParams->size() > 0) { 4845 // This is a declaration or definition of a class template (which may 4846 // be a member of another template). 4847 OwnedDecl = false; 4848 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4849 SS, Name, NameLoc, Attr, 4850 TemplateParams, 4851 AS); 4852 TemplateParameterLists.release(); 4853 return Result.get(); 4854 } else { 4855 // The "template<>" header is extraneous. 4856 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4857 << ElaboratedType::getNameForTagKind(Kind) << Name; 4858 isExplicitSpecialization = true; 4859 } 4860 } 4861 4862 TemplateParameterLists.release(); 4863 } 4864 4865 DeclContext *SearchDC = CurContext; 4866 DeclContext *DC = CurContext; 4867 bool isStdBadAlloc = false; 4868 bool Invalid = false; 4869 4870 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4871 : NotForRedeclaration); 4872 4873 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4874 4875 if (Name && SS.isNotEmpty()) { 4876 // We have a nested-name tag ('struct foo::bar'). 4877 4878 // Check for invalid 'foo::'. 4879 if (SS.isInvalid()) { 4880 Name = 0; 4881 goto CreateNewDecl; 4882 } 4883 4884 // If this is a friend or a reference to a class in a dependent 4885 // context, don't try to make a decl for it. 4886 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4887 DC = computeDeclContext(SS, false); 4888 if (!DC) { 4889 IsDependent = true; 4890 return DeclPtrTy(); 4891 } 4892 } 4893 4894 if (RequireCompleteDeclContext(SS)) 4895 return DeclPtrTy::make((Decl *)0); 4896 4897 DC = computeDeclContext(SS, true); 4898 SearchDC = DC; 4899 // Look-up name inside 'foo::'. 4900 LookupQualifiedName(Previous, DC); 4901 4902 if (Previous.isAmbiguous()) 4903 return DeclPtrTy(); 4904 4905 if (Previous.empty()) { 4906 // Name lookup did not find anything. However, if the 4907 // nested-name-specifier refers to the current instantiation, 4908 // and that current instantiation has any dependent base 4909 // classes, we might find something at instantiation time: treat 4910 // this as a dependent elaborated-type-specifier. 4911 if (Previous.wasNotFoundInCurrentInstantiation()) { 4912 IsDependent = true; 4913 return DeclPtrTy(); 4914 } 4915 4916 // A tag 'foo::bar' must already exist. 4917 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4918 Name = 0; 4919 Invalid = true; 4920 goto CreateNewDecl; 4921 } 4922 } else if (Name) { 4923 // If this is a named struct, check to see if there was a previous forward 4924 // declaration or definition. 4925 // FIXME: We're looking into outer scopes here, even when we 4926 // shouldn't be. Doing so can result in ambiguities that we 4927 // shouldn't be diagnosing. 4928 LookupName(Previous, S); 4929 4930 // Note: there used to be some attempt at recovery here. 4931 if (Previous.isAmbiguous()) 4932 return DeclPtrTy(); 4933 4934 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4935 // FIXME: This makes sure that we ignore the contexts associated 4936 // with C structs, unions, and enums when looking for a matching 4937 // tag declaration or definition. See the similar lookup tweak 4938 // in Sema::LookupName; is there a better way to deal with this? 4939 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4940 SearchDC = SearchDC->getParent(); 4941 } 4942 } 4943 4944 if (Previous.isSingleResult() && 4945 Previous.getFoundDecl()->isTemplateParameter()) { 4946 // Maybe we will complain about the shadowed template parameter. 4947 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4948 // Just pretend that we didn't see the previous declaration. 4949 Previous.clear(); 4950 } 4951 4952 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4953 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4954 // This is a declaration of or a reference to "std::bad_alloc". 4955 isStdBadAlloc = true; 4956 4957 if (Previous.empty() && StdBadAlloc) { 4958 // std::bad_alloc has been implicitly declared (but made invisible to 4959 // name lookup). Fill in this implicit declaration as the previous 4960 // declaration, so that the declarations get chained appropriately. 4961 Previous.addDecl(StdBadAlloc); 4962 } 4963 } 4964 4965 if (!Previous.empty()) { 4966 assert(Previous.isSingleResult()); 4967 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4968 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4969 // If this is a use of a previous tag, or if the tag is already declared 4970 // in the same scope (so that the definition/declaration completes or 4971 // rementions the tag), reuse the decl. 4972 if (TUK == TUK_Reference || TUK == TUK_Friend || 4973 isDeclInScope(PrevDecl, SearchDC, S)) { 4974 // Make sure that this wasn't declared as an enum and now used as a 4975 // struct or something similar. 4976 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4977 bool SafeToContinue 4978 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4979 Kind != TagDecl::TK_enum); 4980 if (SafeToContinue) 4981 Diag(KWLoc, diag::err_use_with_wrong_tag) 4982 << Name 4983 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4984 PrevTagDecl->getKindName()); 4985 else 4986 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4987 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4988 4989 if (SafeToContinue) 4990 Kind = PrevTagDecl->getTagKind(); 4991 else { 4992 // Recover by making this an anonymous redefinition. 4993 Name = 0; 4994 Previous.clear(); 4995 Invalid = true; 4996 } 4997 } 4998 4999 if (!Invalid) { 5000 // If this is a use, just return the declaration we found. 5001 5002 // FIXME: In the future, return a variant or some other clue 5003 // for the consumer of this Decl to know it doesn't own it. 5004 // For our current ASTs this shouldn't be a problem, but will 5005 // need to be changed with DeclGroups. 5006 if (TUK == TUK_Reference || TUK == TUK_Friend) 5007 return DeclPtrTy::make(PrevTagDecl); 5008 5009 // Diagnose attempts to redefine a tag. 5010 if (TUK == TUK_Definition) { 5011 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 5012 // If we're defining a specialization and the previous definition 5013 // is from an implicit instantiation, don't emit an error 5014 // here; we'll catch this in the general case below. 5015 if (!isExplicitSpecialization || 5016 !isa<CXXRecordDecl>(Def) || 5017 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5018 == TSK_ExplicitSpecialization) { 5019 Diag(NameLoc, diag::err_redefinition) << Name; 5020 Diag(Def->getLocation(), diag::note_previous_definition); 5021 // If this is a redefinition, recover by making this 5022 // struct be anonymous, which will make any later 5023 // references get the previous definition. 5024 Name = 0; 5025 Previous.clear(); 5026 Invalid = true; 5027 } 5028 } else { 5029 // If the type is currently being defined, complain 5030 // about a nested redefinition. 5031 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5032 if (Tag->isBeingDefined()) { 5033 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5034 Diag(PrevTagDecl->getLocation(), 5035 diag::note_previous_definition); 5036 Name = 0; 5037 Previous.clear(); 5038 Invalid = true; 5039 } 5040 } 5041 5042 // Okay, this is definition of a previously declared or referenced 5043 // tag PrevDecl. We're going to create a new Decl for it. 5044 } 5045 } 5046 // If we get here we have (another) forward declaration or we 5047 // have a definition. Just create a new decl. 5048 5049 } else { 5050 // If we get here, this is a definition of a new tag type in a nested 5051 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5052 // new decl/type. We set PrevDecl to NULL so that the entities 5053 // have distinct types. 5054 Previous.clear(); 5055 } 5056 // If we get here, we're going to create a new Decl. If PrevDecl 5057 // is non-NULL, it's a definition of the tag declared by 5058 // PrevDecl. If it's NULL, we have a new definition. 5059 } else { 5060 // PrevDecl is a namespace, template, or anything else 5061 // that lives in the IDNS_Tag identifier namespace. 5062 if (isDeclInScope(PrevDecl, SearchDC, S)) { 5063 // The tag name clashes with a namespace name, issue an error and 5064 // recover by making this tag be anonymous. 5065 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5066 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5067 Name = 0; 5068 Previous.clear(); 5069 Invalid = true; 5070 } else { 5071 // The existing declaration isn't relevant to us; we're in a 5072 // new scope, so clear out the previous declaration. 5073 Previous.clear(); 5074 } 5075 } 5076 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 5077 // C++ [basic.scope.pdecl]p5: 5078 // -- for an elaborated-type-specifier of the form 5079 // 5080 // class-key identifier 5081 // 5082 // if the elaborated-type-specifier is used in the 5083 // decl-specifier-seq or parameter-declaration-clause of a 5084 // function defined in namespace scope, the identifier is 5085 // declared as a class-name in the namespace that contains 5086 // the declaration; otherwise, except as a friend 5087 // declaration, the identifier is declared in the smallest 5088 // non-class, non-function-prototype scope that contains the 5089 // declaration. 5090 // 5091 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5092 // C structs and unions. 5093 // 5094 // It is an error in C++ to declare (rather than define) an enum 5095 // type, including via an elaborated type specifier. We'll 5096 // diagnose that later; for now, declare the enum in the same 5097 // scope as we would have picked for any other tag type. 5098 // 5099 // GNU C also supports this behavior as part of its incomplete 5100 // enum types extension, while GNU C++ does not. 5101 // 5102 // Find the context where we'll be declaring the tag. 5103 // FIXME: We would like to maintain the current DeclContext as the 5104 // lexical context, 5105 while (SearchDC->isRecord()) 5106 SearchDC = SearchDC->getParent(); 5107 5108 // Find the scope where we'll be declaring the tag. 5109 while (S->isClassScope() || 5110 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 5111 ((S->getFlags() & Scope::DeclScope) == 0) || 5112 (S->getEntity() && 5113 ((DeclContext *)S->getEntity())->isTransparentContext())) 5114 S = S->getParent(); 5115 5116 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 5117 // C++ [namespace.memdef]p3: 5118 // If a friend declaration in a non-local class first declares a 5119 // class or function, the friend class or function is a member of 5120 // the innermost enclosing namespace. 5121 while (!SearchDC->isFileContext()) 5122 SearchDC = SearchDC->getParent(); 5123 5124 // The entity of a decl scope is a DeclContext; see PushDeclContext. 5125 while (S->getEntity() != SearchDC) 5126 S = S->getParent(); 5127 } 5128 5129CreateNewDecl: 5130 5131 TagDecl *PrevDecl = 0; 5132 if (Previous.isSingleResult()) 5133 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5134 5135 // If there is an identifier, use the location of the identifier as the 5136 // location of the decl, otherwise use the location of the struct/union 5137 // keyword. 5138 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5139 5140 // Otherwise, create a new declaration. If there is a previous 5141 // declaration of the same entity, the two will be linked via 5142 // PrevDecl. 5143 TagDecl *New; 5144 5145 if (Kind == TagDecl::TK_enum) { 5146 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5147 // enum X { A, B, C } D; D should chain to X. 5148 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5149 cast_or_null<EnumDecl>(PrevDecl)); 5150 // If this is an undefined enum, warn. 5151 if (TUK != TUK_Definition && !Invalid) { 5152 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5153 : diag::ext_forward_ref_enum; 5154 Diag(Loc, DK); 5155 } 5156 } else { 5157 // struct/union/class 5158 5159 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5160 // struct X { int A; } D; D should chain to X. 5161 if (getLangOptions().CPlusPlus) { 5162 // FIXME: Look for a way to use RecordDecl for simple structs. 5163 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5164 cast_or_null<CXXRecordDecl>(PrevDecl)); 5165 5166 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5167 StdBadAlloc = cast<CXXRecordDecl>(New); 5168 } else 5169 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5170 cast_or_null<RecordDecl>(PrevDecl)); 5171 } 5172 5173 if (Kind != TagDecl::TK_enum) { 5174 // Handle #pragma pack: if the #pragma pack stack has non-default 5175 // alignment, make up a packed attribute for this decl. These 5176 // attributes are checked when the ASTContext lays out the 5177 // structure. 5178 // 5179 // It is important for implementing the correct semantics that this 5180 // happen here (in act on tag decl). The #pragma pack stack is 5181 // maintained as a result of parser callbacks which can occur at 5182 // many points during the parsing of a struct declaration (because 5183 // the #pragma tokens are effectively skipped over during the 5184 // parsing of the struct). 5185 if (unsigned Alignment = getPragmaPackAlignment()) 5186 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5187 } 5188 5189 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5190 // C++ [dcl.typedef]p3: 5191 // [...] Similarly, in a given scope, a class or enumeration 5192 // shall not be declared with the same name as a typedef-name 5193 // that is declared in that scope and refers to a type other 5194 // than the class or enumeration itself. 5195 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5196 ForRedeclaration); 5197 LookupName(Lookup, S); 5198 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5199 NamedDecl *PrevTypedefNamed = PrevTypedef; 5200 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5201 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5202 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5203 Diag(Loc, diag::err_tag_definition_of_typedef) 5204 << Context.getTypeDeclType(New) 5205 << PrevTypedef->getUnderlyingType(); 5206 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5207 Invalid = true; 5208 } 5209 } 5210 5211 // If this is a specialization of a member class (of a class template), 5212 // check the specialization. 5213 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5214 Invalid = true; 5215 5216 if (Invalid) 5217 New->setInvalidDecl(); 5218 5219 if (Attr) 5220 ProcessDeclAttributeList(S, New, Attr); 5221 5222 // If we're declaring or defining a tag in function prototype scope 5223 // in C, note that this type can only be used within the function. 5224 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5225 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5226 5227 // Set the lexical context. If the tag has a C++ scope specifier, the 5228 // lexical context will be different from the semantic context. 5229 New->setLexicalDeclContext(CurContext); 5230 5231 // Mark this as a friend decl if applicable. 5232 if (TUK == TUK_Friend) 5233 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5234 5235 // Set the access specifier. 5236 if (!Invalid && TUK != TUK_Friend) 5237 SetMemberAccessSpecifier(New, PrevDecl, AS); 5238 5239 if (TUK == TUK_Definition) 5240 New->startDefinition(); 5241 5242 // If this has an identifier, add it to the scope stack. 5243 if (TUK == TUK_Friend) { 5244 // We might be replacing an existing declaration in the lookup tables; 5245 // if so, borrow its access specifier. 5246 if (PrevDecl) 5247 New->setAccess(PrevDecl->getAccess()); 5248 5249 // Friend tag decls are visible in fairly strange ways. 5250 if (!CurContext->isDependentContext()) { 5251 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5252 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5253 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5254 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5255 } 5256 } else if (Name) { 5257 S = getNonFieldDeclScope(S); 5258 PushOnScopeChains(New, S); 5259 } else { 5260 CurContext->addDecl(New); 5261 } 5262 5263 // If this is the C FILE type, notify the AST context. 5264 if (IdentifierInfo *II = New->getIdentifier()) 5265 if (!New->isInvalidDecl() && 5266 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5267 II->isStr("FILE")) 5268 Context.setFILEDecl(New); 5269 5270 OwnedDecl = true; 5271 return DeclPtrTy::make(New); 5272} 5273 5274void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5275 AdjustDeclIfTemplate(TagD); 5276 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5277 5278 // Enter the tag context. 5279 PushDeclContext(S, Tag); 5280} 5281 5282void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5283 SourceLocation LBraceLoc) { 5284 AdjustDeclIfTemplate(TagD); 5285 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5286 5287 FieldCollector->StartClass(); 5288 5289 if (!Record->getIdentifier()) 5290 return; 5291 5292 // C++ [class]p2: 5293 // [...] The class-name is also inserted into the scope of the 5294 // class itself; this is known as the injected-class-name. For 5295 // purposes of access checking, the injected-class-name is treated 5296 // as if it were a public member name. 5297 CXXRecordDecl *InjectedClassName 5298 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5299 CurContext, Record->getLocation(), 5300 Record->getIdentifier(), 5301 Record->getTagKeywordLoc(), 5302 Record); 5303 InjectedClassName->setImplicit(); 5304 InjectedClassName->setAccess(AS_public); 5305 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5306 InjectedClassName->setDescribedClassTemplate(Template); 5307 PushOnScopeChains(InjectedClassName, S); 5308 assert(InjectedClassName->isInjectedClassName() && 5309 "Broken injected-class-name"); 5310} 5311 5312// Traverses the class and any nested classes, making a note of any 5313// dynamic classes that have no key function so that we can mark all of 5314// their virtual member functions as "used" at the end of the translation 5315// unit. This ensures that all functions needed by the vtable will get 5316// instantiated/synthesized. 5317static void 5318RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5319 SourceLocation Loc) { 5320 // We don't look at dependent or undefined classes. 5321 if (Record->isDependentContext() || !Record->isDefinition()) 5322 return; 5323 5324 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 5325 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 5326 5327 for (DeclContext::decl_iterator D = Record->decls_begin(), 5328 DEnd = Record->decls_end(); 5329 D != DEnd; ++D) { 5330 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5331 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5332 } 5333} 5334 5335void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5336 SourceLocation RBraceLoc) { 5337 AdjustDeclIfTemplate(TagD); 5338 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5339 Tag->setRBraceLoc(RBraceLoc); 5340 5341 if (isa<CXXRecordDecl>(Tag)) 5342 FieldCollector->FinishClass(); 5343 5344 // Exit this scope of this tag's definition. 5345 PopDeclContext(); 5346 5347 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 5348 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5349 RBraceLoc); 5350 5351 // Notify the consumer that we've defined a tag. 5352 Consumer.HandleTagDeclDefinition(Tag); 5353} 5354 5355// Note that FieldName may be null for anonymous bitfields. 5356bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5357 QualType FieldTy, const Expr *BitWidth, 5358 bool *ZeroWidth) { 5359 // Default to true; that shouldn't confuse checks for emptiness 5360 if (ZeroWidth) 5361 *ZeroWidth = true; 5362 5363 // C99 6.7.2.1p4 - verify the field type. 5364 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5365 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5366 // Handle incomplete types with specific error. 5367 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5368 return true; 5369 if (FieldName) 5370 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5371 << FieldName << FieldTy << BitWidth->getSourceRange(); 5372 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5373 << FieldTy << BitWidth->getSourceRange(); 5374 } 5375 5376 // If the bit-width is type- or value-dependent, don't try to check 5377 // it now. 5378 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5379 return false; 5380 5381 llvm::APSInt Value; 5382 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5383 return true; 5384 5385 if (Value != 0 && ZeroWidth) 5386 *ZeroWidth = false; 5387 5388 // Zero-width bitfield is ok for anonymous field. 5389 if (Value == 0 && FieldName) 5390 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5391 5392 if (Value.isSigned() && Value.isNegative()) { 5393 if (FieldName) 5394 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5395 << FieldName << Value.toString(10); 5396 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5397 << Value.toString(10); 5398 } 5399 5400 if (!FieldTy->isDependentType()) { 5401 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5402 if (Value.getZExtValue() > TypeSize) { 5403 if (FieldName) 5404 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5405 << FieldName << (unsigned)TypeSize; 5406 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5407 << (unsigned)TypeSize; 5408 } 5409 } 5410 5411 return false; 5412} 5413 5414/// ActOnField - Each field of a struct/union/class is passed into this in order 5415/// to create a FieldDecl object for it. 5416Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5417 SourceLocation DeclStart, 5418 Declarator &D, ExprTy *BitfieldWidth) { 5419 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5420 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5421 AS_public); 5422 return DeclPtrTy::make(Res); 5423} 5424 5425/// HandleField - Analyze a field of a C struct or a C++ data member. 5426/// 5427FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5428 SourceLocation DeclStart, 5429 Declarator &D, Expr *BitWidth, 5430 AccessSpecifier AS) { 5431 IdentifierInfo *II = D.getIdentifier(); 5432 SourceLocation Loc = DeclStart; 5433 if (II) Loc = D.getIdentifierLoc(); 5434 5435 TypeSourceInfo *TInfo = 0; 5436 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5437 if (getLangOptions().CPlusPlus) 5438 CheckExtraCXXDefaultArguments(D); 5439 5440 DiagnoseFunctionSpecifiers(D); 5441 5442 if (D.getDeclSpec().isThreadSpecified()) 5443 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5444 5445 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5446 ForRedeclaration); 5447 5448 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5449 // Maybe we will complain about the shadowed template parameter. 5450 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5451 // Just pretend that we didn't see the previous declaration. 5452 PrevDecl = 0; 5453 } 5454 5455 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5456 PrevDecl = 0; 5457 5458 bool Mutable 5459 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5460 SourceLocation TSSL = D.getSourceRange().getBegin(); 5461 FieldDecl *NewFD 5462 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5463 AS, PrevDecl, &D); 5464 if (NewFD->isInvalidDecl() && PrevDecl) { 5465 // Don't introduce NewFD into scope; there's already something 5466 // with the same name in the same scope. 5467 } else if (II) { 5468 PushOnScopeChains(NewFD, S); 5469 } else 5470 Record->addDecl(NewFD); 5471 5472 return NewFD; 5473} 5474 5475/// \brief Build a new FieldDecl and check its well-formedness. 5476/// 5477/// This routine builds a new FieldDecl given the fields name, type, 5478/// record, etc. \p PrevDecl should refer to any previous declaration 5479/// with the same name and in the same scope as the field to be 5480/// created. 5481/// 5482/// \returns a new FieldDecl. 5483/// 5484/// \todo The Declarator argument is a hack. It will be removed once 5485FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5486 TypeSourceInfo *TInfo, 5487 RecordDecl *Record, SourceLocation Loc, 5488 bool Mutable, Expr *BitWidth, 5489 SourceLocation TSSL, 5490 AccessSpecifier AS, NamedDecl *PrevDecl, 5491 Declarator *D) { 5492 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5493 bool InvalidDecl = false; 5494 if (D) InvalidDecl = D->isInvalidType(); 5495 5496 // If we receive a broken type, recover by assuming 'int' and 5497 // marking this declaration as invalid. 5498 if (T.isNull()) { 5499 InvalidDecl = true; 5500 T = Context.IntTy; 5501 } 5502 5503 QualType EltTy = Context.getBaseElementType(T); 5504 if (!EltTy->isDependentType() && 5505 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5506 InvalidDecl = true; 5507 5508 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5509 // than a variably modified type. 5510 if (!InvalidDecl && T->isVariablyModifiedType()) { 5511 bool SizeIsNegative; 5512 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5513 SizeIsNegative); 5514 if (!FixedTy.isNull()) { 5515 Diag(Loc, diag::warn_illegal_constant_array_size); 5516 T = FixedTy; 5517 } else { 5518 if (SizeIsNegative) 5519 Diag(Loc, diag::err_typecheck_negative_array_size); 5520 else 5521 Diag(Loc, diag::err_typecheck_field_variable_size); 5522 InvalidDecl = true; 5523 } 5524 } 5525 5526 // Fields can not have abstract class types 5527 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5528 diag::err_abstract_type_in_decl, 5529 AbstractFieldType)) 5530 InvalidDecl = true; 5531 5532 bool ZeroWidth = false; 5533 // If this is declared as a bit-field, check the bit-field. 5534 if (!InvalidDecl && BitWidth && 5535 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5536 InvalidDecl = true; 5537 DeleteExpr(BitWidth); 5538 BitWidth = 0; 5539 ZeroWidth = false; 5540 } 5541 5542 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5543 BitWidth, Mutable); 5544 if (InvalidDecl) 5545 NewFD->setInvalidDecl(); 5546 5547 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5548 Diag(Loc, diag::err_duplicate_member) << II; 5549 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5550 NewFD->setInvalidDecl(); 5551 } 5552 5553 if (getLangOptions().CPlusPlus) { 5554 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5555 5556 if (!T->isPODType()) 5557 CXXRecord->setPOD(false); 5558 if (!ZeroWidth) 5559 CXXRecord->setEmpty(false); 5560 5561 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5562 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5563 5564 if (!RDecl->hasTrivialConstructor()) 5565 CXXRecord->setHasTrivialConstructor(false); 5566 if (!RDecl->hasTrivialCopyConstructor()) 5567 CXXRecord->setHasTrivialCopyConstructor(false); 5568 if (!RDecl->hasTrivialCopyAssignment()) 5569 CXXRecord->setHasTrivialCopyAssignment(false); 5570 if (!RDecl->hasTrivialDestructor()) 5571 CXXRecord->setHasTrivialDestructor(false); 5572 5573 // C++ 9.5p1: An object of a class with a non-trivial 5574 // constructor, a non-trivial copy constructor, a non-trivial 5575 // destructor, or a non-trivial copy assignment operator 5576 // cannot be a member of a union, nor can an array of such 5577 // objects. 5578 // TODO: C++0x alters this restriction significantly. 5579 if (Record->isUnion()) { 5580 // We check for copy constructors before constructors 5581 // because otherwise we'll never get complaints about 5582 // copy constructors. 5583 5584 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5585 5586 CXXSpecialMember member; 5587 if (!RDecl->hasTrivialCopyConstructor()) 5588 member = CXXCopyConstructor; 5589 else if (!RDecl->hasTrivialConstructor()) 5590 member = CXXDefaultConstructor; 5591 else if (!RDecl->hasTrivialCopyAssignment()) 5592 member = CXXCopyAssignment; 5593 else if (!RDecl->hasTrivialDestructor()) 5594 member = CXXDestructor; 5595 else 5596 member = invalid; 5597 5598 if (member != invalid) { 5599 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5600 DiagnoseNontrivial(RT, member); 5601 NewFD->setInvalidDecl(); 5602 } 5603 } 5604 } 5605 } 5606 5607 // FIXME: We need to pass in the attributes given an AST 5608 // representation, not a parser representation. 5609 if (D) 5610 // FIXME: What to pass instead of TUScope? 5611 ProcessDeclAttributes(TUScope, NewFD, *D); 5612 5613 if (T.isObjCGCWeak()) 5614 Diag(Loc, diag::warn_attribute_weak_on_field); 5615 5616 NewFD->setAccess(AS); 5617 5618 // C++ [dcl.init.aggr]p1: 5619 // An aggregate is an array or a class (clause 9) with [...] no 5620 // private or protected non-static data members (clause 11). 5621 // A POD must be an aggregate. 5622 if (getLangOptions().CPlusPlus && 5623 (AS == AS_private || AS == AS_protected)) { 5624 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5625 CXXRecord->setAggregate(false); 5626 CXXRecord->setPOD(false); 5627 } 5628 5629 return NewFD; 5630} 5631 5632/// DiagnoseNontrivial - Given that a class has a non-trivial 5633/// special member, figure out why. 5634void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5635 QualType QT(T, 0U); 5636 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5637 5638 // Check whether the member was user-declared. 5639 switch (member) { 5640 case CXXDefaultConstructor: 5641 if (RD->hasUserDeclaredConstructor()) { 5642 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5643 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5644 const FunctionDecl *body = 0; 5645 ci->getBody(body); 5646 if (!body || 5647 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5648 SourceLocation CtorLoc = ci->getLocation(); 5649 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5650 return; 5651 } 5652 } 5653 5654 assert(0 && "found no user-declared constructors"); 5655 return; 5656 } 5657 break; 5658 5659 case CXXCopyConstructor: 5660 if (RD->hasUserDeclaredCopyConstructor()) { 5661 SourceLocation CtorLoc = 5662 RD->getCopyConstructor(Context, 0)->getLocation(); 5663 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5664 return; 5665 } 5666 break; 5667 5668 case CXXCopyAssignment: 5669 if (RD->hasUserDeclaredCopyAssignment()) { 5670 // FIXME: this should use the location of the copy 5671 // assignment, not the type. 5672 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5673 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5674 return; 5675 } 5676 break; 5677 5678 case CXXDestructor: 5679 if (RD->hasUserDeclaredDestructor()) { 5680 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5681 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5682 return; 5683 } 5684 break; 5685 } 5686 5687 typedef CXXRecordDecl::base_class_iterator base_iter; 5688 5689 // Virtual bases and members inhibit trivial copying/construction, 5690 // but not trivial destruction. 5691 if (member != CXXDestructor) { 5692 // Check for virtual bases. vbases includes indirect virtual bases, 5693 // so we just iterate through the direct bases. 5694 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5695 if (bi->isVirtual()) { 5696 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5697 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5698 return; 5699 } 5700 5701 // Check for virtual methods. 5702 typedef CXXRecordDecl::method_iterator meth_iter; 5703 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5704 ++mi) { 5705 if (mi->isVirtual()) { 5706 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5707 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5708 return; 5709 } 5710 } 5711 } 5712 5713 bool (CXXRecordDecl::*hasTrivial)() const; 5714 switch (member) { 5715 case CXXDefaultConstructor: 5716 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5717 case CXXCopyConstructor: 5718 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5719 case CXXCopyAssignment: 5720 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5721 case CXXDestructor: 5722 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5723 default: 5724 assert(0 && "unexpected special member"); return; 5725 } 5726 5727 // Check for nontrivial bases (and recurse). 5728 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5729 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5730 assert(BaseRT && "Don't know how to handle dependent bases"); 5731 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5732 if (!(BaseRecTy->*hasTrivial)()) { 5733 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5734 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5735 DiagnoseNontrivial(BaseRT, member); 5736 return; 5737 } 5738 } 5739 5740 // Check for nontrivial members (and recurse). 5741 typedef RecordDecl::field_iterator field_iter; 5742 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5743 ++fi) { 5744 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5745 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5746 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5747 5748 if (!(EltRD->*hasTrivial)()) { 5749 SourceLocation FLoc = (*fi)->getLocation(); 5750 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5751 DiagnoseNontrivial(EltRT, member); 5752 return; 5753 } 5754 } 5755 } 5756 5757 assert(0 && "found no explanation for non-trivial member"); 5758} 5759 5760/// TranslateIvarVisibility - Translate visibility from a token ID to an 5761/// AST enum value. 5762static ObjCIvarDecl::AccessControl 5763TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5764 switch (ivarVisibility) { 5765 default: assert(0 && "Unknown visitibility kind"); 5766 case tok::objc_private: return ObjCIvarDecl::Private; 5767 case tok::objc_public: return ObjCIvarDecl::Public; 5768 case tok::objc_protected: return ObjCIvarDecl::Protected; 5769 case tok::objc_package: return ObjCIvarDecl::Package; 5770 } 5771} 5772 5773/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5774/// in order to create an IvarDecl object for it. 5775Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5776 SourceLocation DeclStart, 5777 DeclPtrTy IntfDecl, 5778 Declarator &D, ExprTy *BitfieldWidth, 5779 tok::ObjCKeywordKind Visibility) { 5780 5781 IdentifierInfo *II = D.getIdentifier(); 5782 Expr *BitWidth = (Expr*)BitfieldWidth; 5783 SourceLocation Loc = DeclStart; 5784 if (II) Loc = D.getIdentifierLoc(); 5785 5786 // FIXME: Unnamed fields can be handled in various different ways, for 5787 // example, unnamed unions inject all members into the struct namespace! 5788 5789 TypeSourceInfo *TInfo = 0; 5790 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5791 5792 if (BitWidth) { 5793 // 6.7.2.1p3, 6.7.2.1p4 5794 if (VerifyBitField(Loc, II, T, BitWidth)) { 5795 D.setInvalidType(); 5796 DeleteExpr(BitWidth); 5797 BitWidth = 0; 5798 } 5799 } else { 5800 // Not a bitfield. 5801 5802 // validate II. 5803 5804 } 5805 5806 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5807 // than a variably modified type. 5808 if (T->isVariablyModifiedType()) { 5809 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5810 D.setInvalidType(); 5811 } 5812 5813 // Get the visibility (access control) for this ivar. 5814 ObjCIvarDecl::AccessControl ac = 5815 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5816 : ObjCIvarDecl::None; 5817 // Must set ivar's DeclContext to its enclosing interface. 5818 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5819 DeclContext *EnclosingContext; 5820 if (ObjCImplementationDecl *IMPDecl = 5821 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5822 // Case of ivar declared in an implementation. Context is that of its class. 5823 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5824 assert(IDecl && "No class- ActOnIvar"); 5825 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5826 } else 5827 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5828 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5829 5830 // Construct the decl. 5831 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5832 EnclosingContext, Loc, II, T, 5833 TInfo, ac, (Expr *)BitfieldWidth); 5834 5835 if (II) { 5836 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5837 ForRedeclaration); 5838 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5839 && !isa<TagDecl>(PrevDecl)) { 5840 Diag(Loc, diag::err_duplicate_member) << II; 5841 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5842 NewID->setInvalidDecl(); 5843 } 5844 } 5845 5846 // Process attributes attached to the ivar. 5847 ProcessDeclAttributes(S, NewID, D); 5848 5849 if (D.isInvalidType()) 5850 NewID->setInvalidDecl(); 5851 5852 if (II) { 5853 // FIXME: When interfaces are DeclContexts, we'll need to add 5854 // these to the interface. 5855 S->AddDecl(DeclPtrTy::make(NewID)); 5856 IdResolver.AddDecl(NewID); 5857 } 5858 5859 return DeclPtrTy::make(NewID); 5860} 5861 5862void Sema::ActOnFields(Scope* S, 5863 SourceLocation RecLoc, DeclPtrTy RecDecl, 5864 DeclPtrTy *Fields, unsigned NumFields, 5865 SourceLocation LBrac, SourceLocation RBrac, 5866 AttributeList *Attr) { 5867 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5868 assert(EnclosingDecl && "missing record or interface decl"); 5869 5870 // If the decl this is being inserted into is invalid, then it may be a 5871 // redeclaration or some other bogus case. Don't try to add fields to it. 5872 if (EnclosingDecl->isInvalidDecl()) { 5873 // FIXME: Deallocate fields? 5874 return; 5875 } 5876 5877 5878 // Verify that all the fields are okay. 5879 unsigned NumNamedMembers = 0; 5880 llvm::SmallVector<FieldDecl*, 32> RecFields; 5881 5882 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5883 for (unsigned i = 0; i != NumFields; ++i) { 5884 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5885 5886 // Get the type for the field. 5887 Type *FDTy = FD->getType().getTypePtr(); 5888 5889 if (!FD->isAnonymousStructOrUnion()) { 5890 // Remember all fields written by the user. 5891 RecFields.push_back(FD); 5892 } 5893 5894 // If the field is already invalid for some reason, don't emit more 5895 // diagnostics about it. 5896 if (FD->isInvalidDecl()) { 5897 EnclosingDecl->setInvalidDecl(); 5898 continue; 5899 } 5900 5901 // C99 6.7.2.1p2: 5902 // A structure or union shall not contain a member with 5903 // incomplete or function type (hence, a structure shall not 5904 // contain an instance of itself, but may contain a pointer to 5905 // an instance of itself), except that the last member of a 5906 // structure with more than one named member may have incomplete 5907 // array type; such a structure (and any union containing, 5908 // possibly recursively, a member that is such a structure) 5909 // shall not be a member of a structure or an element of an 5910 // array. 5911 if (FDTy->isFunctionType()) { 5912 // Field declared as a function. 5913 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5914 << FD->getDeclName(); 5915 FD->setInvalidDecl(); 5916 EnclosingDecl->setInvalidDecl(); 5917 continue; 5918 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5919 Record && Record->isStruct()) { 5920 // Flexible array member. 5921 if (NumNamedMembers < 1) { 5922 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5923 << FD->getDeclName(); 5924 FD->setInvalidDecl(); 5925 EnclosingDecl->setInvalidDecl(); 5926 continue; 5927 } 5928 // Okay, we have a legal flexible array member at the end of the struct. 5929 if (Record) 5930 Record->setHasFlexibleArrayMember(true); 5931 } else if (!FDTy->isDependentType() && 5932 RequireCompleteType(FD->getLocation(), FD->getType(), 5933 diag::err_field_incomplete)) { 5934 // Incomplete type 5935 FD->setInvalidDecl(); 5936 EnclosingDecl->setInvalidDecl(); 5937 continue; 5938 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5939 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5940 // If this is a member of a union, then entire union becomes "flexible". 5941 if (Record && Record->isUnion()) { 5942 Record->setHasFlexibleArrayMember(true); 5943 } else { 5944 // If this is a struct/class and this is not the last element, reject 5945 // it. Note that GCC supports variable sized arrays in the middle of 5946 // structures. 5947 if (i != NumFields-1) 5948 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5949 << FD->getDeclName() << FD->getType(); 5950 else { 5951 // We support flexible arrays at the end of structs in 5952 // other structs as an extension. 5953 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5954 << FD->getDeclName(); 5955 if (Record) 5956 Record->setHasFlexibleArrayMember(true); 5957 } 5958 } 5959 } 5960 if (Record && FDTTy->getDecl()->hasObjectMember()) 5961 Record->setHasObjectMember(true); 5962 } else if (FDTy->isObjCInterfaceType()) { 5963 /// A field cannot be an Objective-c object 5964 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5965 FD->setInvalidDecl(); 5966 EnclosingDecl->setInvalidDecl(); 5967 continue; 5968 } else if (getLangOptions().ObjC1 && 5969 getLangOptions().getGCMode() != LangOptions::NonGC && 5970 Record && 5971 (FD->getType()->isObjCObjectPointerType() || 5972 FD->getType().isObjCGCStrong())) 5973 Record->setHasObjectMember(true); 5974 // Keep track of the number of named members. 5975 if (FD->getIdentifier()) 5976 ++NumNamedMembers; 5977 } 5978 5979 // Okay, we successfully defined 'Record'. 5980 if (Record) { 5981 Record->completeDefinition(Context); 5982 } else { 5983 ObjCIvarDecl **ClsFields = 5984 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5985 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5986 ID->setIVarList(ClsFields, RecFields.size(), Context); 5987 ID->setLocEnd(RBrac); 5988 // Add ivar's to class's DeclContext. 5989 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5990 ClsFields[i]->setLexicalDeclContext(ID); 5991 ID->addDecl(ClsFields[i]); 5992 } 5993 // Must enforce the rule that ivars in the base classes may not be 5994 // duplicates. 5995 if (ID->getSuperClass()) { 5996 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5997 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5998 ObjCIvarDecl* Ivar = (*IVI); 5999 6000 if (IdentifierInfo *II = Ivar->getIdentifier()) { 6001 ObjCIvarDecl* prevIvar = 6002 ID->getSuperClass()->lookupInstanceVariable(II); 6003 if (prevIvar) { 6004 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 6005 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 6006 } 6007 } 6008 } 6009 } 6010 } else if (ObjCImplementationDecl *IMPDecl = 6011 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6012 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6013 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6014 // Ivar declared in @implementation never belongs to the implementation. 6015 // Only it is in implementation's lexical context. 6016 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6017 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6018 } 6019 } 6020 6021 if (Attr) 6022 ProcessDeclAttributeList(S, Record, Attr); 6023} 6024 6025EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6026 EnumConstantDecl *LastEnumConst, 6027 SourceLocation IdLoc, 6028 IdentifierInfo *Id, 6029 ExprArg val) { 6030 Expr *Val = (Expr *)val.get(); 6031 6032 llvm::APSInt EnumVal(32); 6033 QualType EltTy; 6034 if (Val) { 6035 if (Enum->isDependentType()) 6036 EltTy = Context.DependentTy; 6037 else { 6038 // Make sure to promote the operand type to int. 6039 UsualUnaryConversions(Val); 6040 if (Val != val.get()) { 6041 val.release(); 6042 val = Val; 6043 } 6044 6045 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6046 SourceLocation ExpLoc; 6047 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 6048 Val = 0; 6049 } else { 6050 EltTy = Val->getType(); 6051 } 6052 } 6053 } 6054 6055 if (!Val) { 6056 if (Enum->isDependentType()) 6057 EltTy = Context.DependentTy; 6058 else if (LastEnumConst) { 6059 // Assign the last value + 1. 6060 EnumVal = LastEnumConst->getInitVal(); 6061 ++EnumVal; 6062 6063 // Check for overflow on increment. 6064 if (EnumVal < LastEnumConst->getInitVal()) 6065 Diag(IdLoc, diag::warn_enum_value_overflow); 6066 6067 EltTy = LastEnumConst->getType(); 6068 } else { 6069 // First value, set to zero. 6070 EltTy = Context.IntTy; 6071 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 6072 EnumVal.setIsSigned(true); 6073 } 6074 } 6075 6076 assert(!EltTy.isNull() && "Enum constant with NULL type"); 6077 6078 val.release(); 6079 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6080 Val, EnumVal); 6081} 6082 6083 6084Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6085 DeclPtrTy lastEnumConst, 6086 SourceLocation IdLoc, 6087 IdentifierInfo *Id, 6088 SourceLocation EqualLoc, ExprTy *val) { 6089 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6090 EnumConstantDecl *LastEnumConst = 6091 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6092 Expr *Val = static_cast<Expr*>(val); 6093 6094 // The scope passed in may not be a decl scope. Zip up the scope tree until 6095 // we find one that is. 6096 S = getNonFieldDeclScope(S); 6097 6098 // Verify that there isn't already something declared with this name in this 6099 // scope. 6100 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 6101 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6102 // Maybe we will complain about the shadowed template parameter. 6103 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6104 // Just pretend that we didn't see the previous declaration. 6105 PrevDecl = 0; 6106 } 6107 6108 if (PrevDecl) { 6109 // When in C++, we may get a TagDecl with the same name; in this case the 6110 // enum constant will 'hide' the tag. 6111 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6112 "Received TagDecl when not in C++!"); 6113 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6114 if (isa<EnumConstantDecl>(PrevDecl)) 6115 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6116 else 6117 Diag(IdLoc, diag::err_redefinition) << Id; 6118 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6119 if (Val) Val->Destroy(Context); 6120 return DeclPtrTy(); 6121 } 6122 } 6123 6124 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6125 IdLoc, Id, Owned(Val)); 6126 6127 // Register this decl in the current scope stack. 6128 if (New) 6129 PushOnScopeChains(New, S); 6130 6131 return DeclPtrTy::make(New); 6132} 6133 6134void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6135 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6136 DeclPtrTy *Elements, unsigned NumElements, 6137 Scope *S, AttributeList *Attr) { 6138 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6139 QualType EnumType = Context.getTypeDeclType(Enum); 6140 6141 if (Attr) 6142 ProcessDeclAttributeList(S, Enum, Attr); 6143 6144 if (Enum->isDependentType()) { 6145 for (unsigned i = 0; i != NumElements; ++i) { 6146 EnumConstantDecl *ECD = 6147 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6148 if (!ECD) continue; 6149 6150 ECD->setType(EnumType); 6151 } 6152 6153 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 6154 return; 6155 } 6156 6157 // TODO: If the result value doesn't fit in an int, it must be a long or long 6158 // long value. ISO C does not support this, but GCC does as an extension, 6159 // emit a warning. 6160 unsigned IntWidth = Context.Target.getIntWidth(); 6161 unsigned CharWidth = Context.Target.getCharWidth(); 6162 unsigned ShortWidth = Context.Target.getShortWidth(); 6163 6164 // Verify that all the values are okay, compute the size of the values, and 6165 // reverse the list. 6166 unsigned NumNegativeBits = 0; 6167 unsigned NumPositiveBits = 0; 6168 6169 // Keep track of whether all elements have type int. 6170 bool AllElementsInt = true; 6171 6172 for (unsigned i = 0; i != NumElements; ++i) { 6173 EnumConstantDecl *ECD = 6174 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6175 if (!ECD) continue; // Already issued a diagnostic. 6176 6177 // If the enum value doesn't fit in an int, emit an extension warning. 6178 const llvm::APSInt &InitVal = ECD->getInitVal(); 6179 assert(InitVal.getBitWidth() >= IntWidth && 6180 "Should have promoted value to int"); 6181 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 6182 llvm::APSInt V(InitVal); 6183 V.trunc(IntWidth); 6184 V.extend(InitVal.getBitWidth()); 6185 if (V != InitVal) 6186 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 6187 << InitVal.toString(10); 6188 } 6189 6190 // Keep track of the size of positive and negative values. 6191 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6192 NumPositiveBits = std::max(NumPositiveBits, 6193 (unsigned)InitVal.getActiveBits()); 6194 else 6195 NumNegativeBits = std::max(NumNegativeBits, 6196 (unsigned)InitVal.getMinSignedBits()); 6197 6198 // Keep track of whether every enum element has type int (very commmon). 6199 if (AllElementsInt) 6200 AllElementsInt = ECD->getType() == Context.IntTy; 6201 } 6202 6203 // Figure out the type that should be used for this enum. 6204 // FIXME: Support -fshort-enums. 6205 QualType BestType; 6206 unsigned BestWidth; 6207 6208 // C++0x N3000 [conv.prom]p3: 6209 // An rvalue of an unscoped enumeration type whose underlying 6210 // type is not fixed can be converted to an rvalue of the first 6211 // of the following types that can represent all the values of 6212 // the enumeration: int, unsigned int, long int, unsigned long 6213 // int, long long int, or unsigned long long int. 6214 // C99 6.4.4.3p2: 6215 // An identifier declared as an enumeration constant has type int. 6216 // The C99 rule is modified by a gcc extension 6217 QualType BestPromotionType; 6218 6219 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6220 6221 if (NumNegativeBits) { 6222 // If there is a negative value, figure out the smallest integer type (of 6223 // int/long/longlong) that fits. 6224 // If it's packed, check also if it fits a char or a short. 6225 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6226 BestType = Context.SignedCharTy; 6227 BestWidth = CharWidth; 6228 } else if (Packed && NumNegativeBits <= ShortWidth && 6229 NumPositiveBits < ShortWidth) { 6230 BestType = Context.ShortTy; 6231 BestWidth = ShortWidth; 6232 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6233 BestType = Context.IntTy; 6234 BestWidth = IntWidth; 6235 } else { 6236 BestWidth = Context.Target.getLongWidth(); 6237 6238 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6239 BestType = Context.LongTy; 6240 } else { 6241 BestWidth = Context.Target.getLongLongWidth(); 6242 6243 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6244 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6245 BestType = Context.LongLongTy; 6246 } 6247 } 6248 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6249 } else { 6250 // If there is no negative value, figure out which of uint, ulong, ulonglong 6251 // fits. 6252 // If it's packed, check also if it fits a char or a short. 6253 if (Packed && NumPositiveBits <= CharWidth) { 6254 BestType = Context.UnsignedCharTy; 6255 BestPromotionType = Context.IntTy; 6256 BestWidth = CharWidth; 6257 } else if (Packed && NumPositiveBits <= ShortWidth) { 6258 BestType = Context.UnsignedShortTy; 6259 BestPromotionType = Context.IntTy; 6260 BestWidth = ShortWidth; 6261 } else if (NumPositiveBits <= IntWidth) { 6262 BestType = Context.UnsignedIntTy; 6263 BestWidth = IntWidth; 6264 BestPromotionType = (NumPositiveBits == BestWidth 6265 ? Context.UnsignedIntTy : Context.IntTy); 6266 } else if (NumPositiveBits <= 6267 (BestWidth = Context.Target.getLongWidth())) { 6268 BestType = Context.UnsignedLongTy; 6269 BestPromotionType = (NumPositiveBits == BestWidth 6270 ? Context.UnsignedLongTy : Context.LongTy); 6271 } else { 6272 BestWidth = Context.Target.getLongLongWidth(); 6273 assert(NumPositiveBits <= BestWidth && 6274 "How could an initializer get larger than ULL?"); 6275 BestType = Context.UnsignedLongLongTy; 6276 BestPromotionType = (NumPositiveBits == BestWidth 6277 ? Context.UnsignedLongLongTy : Context.LongLongTy); 6278 } 6279 } 6280 6281 // If we're in C and the promotion type is larger than an int, just 6282 // use the underlying type, which is generally the unsigned integer 6283 // type of the same rank as the promotion type. This is how the gcc 6284 // extension works. 6285 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 6286 BestPromotionType = BestType; 6287 6288 // Loop over all of the enumerator constants, changing their types to match 6289 // the type of the enum if needed. 6290 for (unsigned i = 0; i != NumElements; ++i) { 6291 EnumConstantDecl *ECD = 6292 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6293 if (!ECD) continue; // Already issued a diagnostic. 6294 6295 // Standard C says the enumerators have int type, but we allow, as an 6296 // extension, the enumerators to be larger than int size. If each 6297 // enumerator value fits in an int, type it as an int, otherwise type it the 6298 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6299 // that X has type 'int', not 'unsigned'. 6300 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 6301 continue; 6302 6303 // Determine whether the value fits into an int. 6304 llvm::APSInt InitVal = ECD->getInitVal(); 6305 bool FitsInInt; 6306 if (InitVal.isUnsigned() || !InitVal.isNegative()) 6307 FitsInInt = InitVal.getActiveBits() < IntWidth; 6308 else 6309 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 6310 6311 // If it fits into an integer type, force it. Otherwise force it to match 6312 // the enum decl type. 6313 QualType NewTy; 6314 unsigned NewWidth; 6315 bool NewSign; 6316 if (FitsInInt && !getLangOptions().CPlusPlus) { 6317 NewTy = Context.IntTy; 6318 NewWidth = IntWidth; 6319 NewSign = true; 6320 } else if (ECD->getType() == BestType) { 6321 // Already the right type! 6322 if (getLangOptions().CPlusPlus) 6323 // C++ [dcl.enum]p4: Following the closing brace of an 6324 // enum-specifier, each enumerator has the type of its 6325 // enumeration. 6326 ECD->setType(EnumType); 6327 continue; 6328 } else { 6329 NewTy = BestType; 6330 NewWidth = BestWidth; 6331 NewSign = BestType->isSignedIntegerType(); 6332 } 6333 6334 // Adjust the APSInt value. 6335 InitVal.extOrTrunc(NewWidth); 6336 InitVal.setIsSigned(NewSign); 6337 ECD->setInitVal(InitVal); 6338 6339 // Adjust the Expr initializer and type. 6340 if (ECD->getInitExpr()) 6341 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6342 CastExpr::CK_IntegralCast, 6343 ECD->getInitExpr(), 6344 /*isLvalue=*/false)); 6345 if (getLangOptions().CPlusPlus) 6346 // C++ [dcl.enum]p4: Following the closing brace of an 6347 // enum-specifier, each enumerator has the type of its 6348 // enumeration. 6349 ECD->setType(EnumType); 6350 else 6351 ECD->setType(NewTy); 6352 } 6353 6354 Enum->completeDefinition(Context, BestType, BestPromotionType); 6355} 6356 6357Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6358 ExprArg expr) { 6359 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6360 6361 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6362 Loc, AsmString); 6363 CurContext->addDecl(New); 6364 return DeclPtrTy::make(New); 6365} 6366 6367void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6368 SourceLocation PragmaLoc, 6369 SourceLocation NameLoc) { 6370 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6371 6372 if (PrevDecl) { 6373 PrevDecl->addAttr(::new (Context) WeakAttr()); 6374 } else { 6375 (void)WeakUndeclaredIdentifiers.insert( 6376 std::pair<IdentifierInfo*,WeakInfo> 6377 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6378 } 6379} 6380 6381void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6382 IdentifierInfo* AliasName, 6383 SourceLocation PragmaLoc, 6384 SourceLocation NameLoc, 6385 SourceLocation AliasNameLoc) { 6386 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6387 WeakInfo W = WeakInfo(Name, NameLoc); 6388 6389 if (PrevDecl) { 6390 if (!PrevDecl->hasAttr<AliasAttr>()) 6391 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6392 DeclApplyPragmaWeak(TUScope, ND, W); 6393 } else { 6394 (void)WeakUndeclaredIdentifiers.insert( 6395 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6396 } 6397} 6398