SemaDecl.cpp revision 0fe2256a5f250149806a989986758a2af96ba281
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::FoundOverloaded: 142 case LookupResult::FoundUnresolvedValue: 143 return 0; 144 145 case LookupResult::Ambiguous: 146 // Recover from type-hiding ambiguities by hiding the type. We'll 147 // do the lookup again when looking for an object, and we can 148 // diagnose the error then. If we don't do this, then the error 149 // about hiding the type will be immediately followed by an error 150 // that only makes sense if the identifier was treated like a type. 151 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 152 Result.suppressDiagnostics(); 153 return 0; 154 } 155 156 // Look to see if we have a type anywhere in the list of results. 157 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 158 Res != ResEnd; ++Res) { 159 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 160 if (!IIDecl || 161 (*Res)->getLocation().getRawEncoding() < 162 IIDecl->getLocation().getRawEncoding()) 163 IIDecl = *Res; 164 } 165 } 166 167 if (!IIDecl) { 168 // None of the entities we found is a type, so there is no way 169 // to even assume that the result is a type. In this case, don't 170 // complain about the ambiguity. The parser will either try to 171 // perform this lookup again (e.g., as an object name), which 172 // will produce the ambiguity, or will complain that it expected 173 // a type name. 174 Result.suppressDiagnostics(); 175 return 0; 176 } 177 178 // We found a type within the ambiguous lookup; diagnose the 179 // ambiguity and then return that type. This might be the right 180 // answer, or it might not be, but it suppresses any attempt to 181 // perform the name lookup again. 182 break; 183 184 case LookupResult::Found: 185 IIDecl = Result.getFoundDecl(); 186 break; 187 } 188 189 assert(IIDecl && "Didn't find decl"); 190 191 QualType T; 192 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 193 DiagnoseUseOfDecl(IIDecl, NameLoc); 194 195 // C++ [temp.local]p2: 196 // Within the scope of a class template specialization or 197 // partial specialization, when the injected-class-name is 198 // not followed by a <, it is equivalent to the 199 // injected-class-name followed by the template-argument s 200 // of the class template specialization or partial 201 // specialization enclosed in <>. 202 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 203 if (RD->isInjectedClassName()) 204 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 205 T = Template->getInjectedClassNameType(Context); 206 207 if (T.isNull()) 208 T = Context.getTypeDeclType(TD); 209 210 if (SS) 211 T = getQualifiedNameType(*SS, T); 212 213 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 214 T = Context.getObjCInterfaceType(IDecl); 215 } else if (UnresolvedUsingTypenameDecl *UUDecl = 216 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 217 // FIXME: preserve source structure information. 218 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 219 } else { 220 // If it's not plausibly a type, suppress diagnostics. 221 Result.suppressDiagnostics(); 222 return 0; 223 } 224 225 return T.getAsOpaquePtr(); 226} 227 228/// isTagName() - This method is called *for error recovery purposes only* 229/// to determine if the specified name is a valid tag name ("struct foo"). If 230/// so, this returns the TST for the tag corresponding to it (TST_enum, 231/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 232/// where the user forgot to specify the tag. 233DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 234 // Do a tag name lookup in this scope. 235 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 236 LookupName(R, S, false); 237 R.suppressDiagnostics(); 238 if (R.getResultKind() == LookupResult::Found) 239 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 240 switch (TD->getTagKind()) { 241 case TagDecl::TK_struct: return DeclSpec::TST_struct; 242 case TagDecl::TK_union: return DeclSpec::TST_union; 243 case TagDecl::TK_class: return DeclSpec::TST_class; 244 case TagDecl::TK_enum: return DeclSpec::TST_enum; 245 } 246 } 247 248 return DeclSpec::TST_unspecified; 249} 250 251bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 252 SourceLocation IILoc, 253 Scope *S, 254 const CXXScopeSpec *SS, 255 TypeTy *&SuggestedType) { 256 // We don't have anything to suggest (yet). 257 SuggestedType = 0; 258 259 // There may have been a typo in the name of the type. Look up typo 260 // results, in case we have something that we can suggest. 261 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 262 NotForRedeclaration); 263 264 // FIXME: It would be nice if we could correct for typos in built-in 265 // names, such as "itn" for "int". 266 267 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 268 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 269 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 270 !Result->isInvalidDecl()) { 271 // We found a similarly-named type or interface; suggest that. 272 if (!SS || !SS->isSet()) 273 Diag(IILoc, diag::err_unknown_typename_suggest) 274 << &II << Lookup.getLookupName() 275 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 276 Result->getNameAsString()); 277 else if (DeclContext *DC = computeDeclContext(*SS, false)) 278 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 279 << &II << DC << Lookup.getLookupName() << SS->getRange() 280 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 281 Result->getNameAsString()); 282 else 283 llvm_unreachable("could not have corrected a typo here"); 284 285 Diag(Result->getLocation(), diag::note_previous_decl) 286 << Result->getDeclName(); 287 288 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 289 return true; 290 } 291 } 292 293 // FIXME: Should we move the logic that tries to recover from a missing tag 294 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 295 296 if (!SS || (!SS->isSet() && !SS->isInvalid())) 297 Diag(IILoc, diag::err_unknown_typename) << &II; 298 else if (DeclContext *DC = computeDeclContext(*SS, false)) 299 Diag(IILoc, diag::err_typename_nested_not_found) 300 << &II << DC << SS->getRange(); 301 else if (isDependentScopeSpecifier(*SS)) { 302 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 303 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 304 << SourceRange(SS->getRange().getBegin(), IILoc) 305 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 306 "typename "); 307 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 308 } else { 309 assert(SS && SS->isInvalid() && 310 "Invalid scope specifier has already been diagnosed"); 311 } 312 313 return true; 314} 315 316// Determines the context to return to after temporarily entering a 317// context. This depends in an unnecessarily complicated way on the 318// exact ordering of callbacks from the parser. 319DeclContext *Sema::getContainingDC(DeclContext *DC) { 320 321 // Functions defined inline within classes aren't parsed until we've 322 // finished parsing the top-level class, so the top-level class is 323 // the context we'll need to return to. 324 if (isa<FunctionDecl>(DC)) { 325 DC = DC->getLexicalParent(); 326 327 // A function not defined within a class will always return to its 328 // lexical context. 329 if (!isa<CXXRecordDecl>(DC)) 330 return DC; 331 332 // A C++ inline method/friend is parsed *after* the topmost class 333 // it was declared in is fully parsed ("complete"); the topmost 334 // class is the context we need to return to. 335 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 336 DC = RD; 337 338 // Return the declaration context of the topmost class the inline method is 339 // declared in. 340 return DC; 341 } 342 343 if (isa<ObjCMethodDecl>(DC)) 344 return Context.getTranslationUnitDecl(); 345 346 return DC->getLexicalParent(); 347} 348 349void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 350 assert(getContainingDC(DC) == CurContext && 351 "The next DeclContext should be lexically contained in the current one."); 352 CurContext = DC; 353 S->setEntity(DC); 354} 355 356void Sema::PopDeclContext() { 357 assert(CurContext && "DeclContext imbalance!"); 358 359 CurContext = getContainingDC(CurContext); 360} 361 362/// EnterDeclaratorContext - Used when we must lookup names in the context 363/// of a declarator's nested name specifier. 364/// 365void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 366 // C++0x [basic.lookup.unqual]p13: 367 // A name used in the definition of a static data member of class 368 // X (after the qualified-id of the static member) is looked up as 369 // if the name was used in a member function of X. 370 // C++0x [basic.lookup.unqual]p14: 371 // If a variable member of a namespace is defined outside of the 372 // scope of its namespace then any name used in the definition of 373 // the variable member (after the declarator-id) is looked up as 374 // if the definition of the variable member occurred in its 375 // namespace. 376 // Both of these imply that we should push a scope whose context 377 // is the semantic context of the declaration. We can't use 378 // PushDeclContext here because that context is not necessarily 379 // lexically contained in the current context. Fortunately, 380 // the containing scope should have the appropriate information. 381 382 assert(!S->getEntity() && "scope already has entity"); 383 384#ifndef NDEBUG 385 Scope *Ancestor = S->getParent(); 386 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 387 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 388#endif 389 390 CurContext = DC; 391 S->setEntity(DC); 392} 393 394void Sema::ExitDeclaratorContext(Scope *S) { 395 assert(S->getEntity() == CurContext && "Context imbalance!"); 396 397 // Switch back to the lexical context. The safety of this is 398 // enforced by an assert in EnterDeclaratorContext. 399 Scope *Ancestor = S->getParent(); 400 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 401 CurContext = (DeclContext*) Ancestor->getEntity(); 402 403 // We don't need to do anything with the scope, which is going to 404 // disappear. 405} 406 407/// \brief Determine whether we allow overloading of the function 408/// PrevDecl with another declaration. 409/// 410/// This routine determines whether overloading is possible, not 411/// whether some new function is actually an overload. It will return 412/// true in C++ (where we can always provide overloads) or, as an 413/// extension, in C when the previous function is already an 414/// overloaded function declaration or has the "overloadable" 415/// attribute. 416static bool AllowOverloadingOfFunction(LookupResult &Previous, 417 ASTContext &Context) { 418 if (Context.getLangOptions().CPlusPlus) 419 return true; 420 421 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 422 return true; 423 424 return (Previous.getResultKind() == LookupResult::Found 425 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 426} 427 428/// Add this decl to the scope shadowed decl chains. 429void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 430 // Move up the scope chain until we find the nearest enclosing 431 // non-transparent context. The declaration will be introduced into this 432 // scope. 433 while (S->getEntity() && 434 ((DeclContext *)S->getEntity())->isTransparentContext()) 435 S = S->getParent(); 436 437 // Add scoped declarations into their context, so that they can be 438 // found later. Declarations without a context won't be inserted 439 // into any context. 440 if (AddToContext) 441 CurContext->addDecl(D); 442 443 // Out-of-line function and variable definitions should not be pushed into 444 // scope. 445 if ((isa<FunctionTemplateDecl>(D) && 446 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 447 (isa<FunctionDecl>(D) && 448 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 449 cast<FunctionDecl>(D)->isOutOfLine())) || 450 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 451 return; 452 453 // If this replaces anything in the current scope, 454 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 455 IEnd = IdResolver.end(); 456 for (; I != IEnd; ++I) { 457 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 458 S->RemoveDecl(DeclPtrTy::make(*I)); 459 IdResolver.RemoveDecl(*I); 460 461 // Should only need to replace one decl. 462 break; 463 } 464 } 465 466 S->AddDecl(DeclPtrTy::make(D)); 467 IdResolver.AddDecl(D); 468} 469 470bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 471 return IdResolver.isDeclInScope(D, Ctx, Context, S); 472} 473 474static bool isOutOfScopePreviousDeclaration(NamedDecl *, 475 DeclContext*, 476 ASTContext&); 477 478/// Filters out lookup results that don't fall within the given scope 479/// as determined by isDeclInScope. 480static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 481 DeclContext *Ctx, Scope *S, 482 bool ConsiderLinkage) { 483 LookupResult::Filter F = R.makeFilter(); 484 while (F.hasNext()) { 485 NamedDecl *D = F.next(); 486 487 if (SemaRef.isDeclInScope(D, Ctx, S)) 488 continue; 489 490 if (ConsiderLinkage && 491 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 492 continue; 493 494 F.erase(); 495 } 496 497 F.done(); 498} 499 500static bool isUsingDecl(NamedDecl *D) { 501 return isa<UsingShadowDecl>(D) || 502 isa<UnresolvedUsingTypenameDecl>(D) || 503 isa<UnresolvedUsingValueDecl>(D); 504} 505 506/// Removes using shadow declarations from the lookup results. 507static void RemoveUsingDecls(LookupResult &R) { 508 LookupResult::Filter F = R.makeFilter(); 509 while (F.hasNext()) 510 if (isUsingDecl(F.next())) 511 F.erase(); 512 513 F.done(); 514} 515 516static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 517 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 518 return false; 519 520 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 521 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 522 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 523 if (!RD->hasTrivialConstructor()) 524 return false; 525 if (!RD->hasTrivialDestructor()) 526 return false; 527 } 528 } 529 } 530 531 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 532 !isa<ImplicitParamDecl>(D) && 533 D->getDeclContext()->isFunctionOrMethod()); 534} 535 536void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 537 if (S->decl_empty()) return; 538 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 539 "Scope shouldn't contain decls!"); 540 541 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 542 I != E; ++I) { 543 Decl *TmpD = (*I).getAs<Decl>(); 544 assert(TmpD && "This decl didn't get pushed??"); 545 546 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 547 NamedDecl *D = cast<NamedDecl>(TmpD); 548 549 if (!D->getDeclName()) continue; 550 551 // Diagnose unused variables in this scope. 552 if (ShouldDiagnoseUnusedDecl(D)) 553 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 554 555 // Remove this name from our lexical scope. 556 IdResolver.RemoveDecl(D); 557 } 558} 559 560/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 561/// return 0 if one not found. 562/// 563/// \param Id the name of the Objective-C class we're looking for. If 564/// typo-correction fixes this name, the Id will be updated 565/// to the fixed name. 566/// 567/// \param RecoverLoc if provided, this routine will attempt to 568/// recover from a typo in the name of an existing Objective-C class 569/// and, if successful, will return the lookup that results from 570/// typo-correction. 571ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 572 SourceLocation RecoverLoc) { 573 // The third "scope" argument is 0 since we aren't enabling lazy built-in 574 // creation from this context. 575 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 576 577 if (!IDecl && !RecoverLoc.isInvalid()) { 578 // Perform typo correction at the given location, but only if we 579 // find an Objective-C class name. 580 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 581 if (CorrectTypo(R, TUScope, 0) && 582 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 583 Diag(RecoverLoc, diag::err_undef_interface_suggest) 584 << Id << IDecl->getDeclName() 585 << CodeModificationHint::CreateReplacement(RecoverLoc, 586 IDecl->getNameAsString()); 587 Diag(IDecl->getLocation(), diag::note_previous_decl) 588 << IDecl->getDeclName(); 589 590 Id = IDecl->getIdentifier(); 591 } 592 } 593 594 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 595} 596 597/// getNonFieldDeclScope - Retrieves the innermost scope, starting 598/// from S, where a non-field would be declared. This routine copes 599/// with the difference between C and C++ scoping rules in structs and 600/// unions. For example, the following code is well-formed in C but 601/// ill-formed in C++: 602/// @code 603/// struct S6 { 604/// enum { BAR } e; 605/// }; 606/// 607/// void test_S6() { 608/// struct S6 a; 609/// a.e = BAR; 610/// } 611/// @endcode 612/// For the declaration of BAR, this routine will return a different 613/// scope. The scope S will be the scope of the unnamed enumeration 614/// within S6. In C++, this routine will return the scope associated 615/// with S6, because the enumeration's scope is a transparent 616/// context but structures can contain non-field names. In C, this 617/// routine will return the translation unit scope, since the 618/// enumeration's scope is a transparent context and structures cannot 619/// contain non-field names. 620Scope *Sema::getNonFieldDeclScope(Scope *S) { 621 while (((S->getFlags() & Scope::DeclScope) == 0) || 622 (S->getEntity() && 623 ((DeclContext *)S->getEntity())->isTransparentContext()) || 624 (S->isClassScope() && !getLangOptions().CPlusPlus)) 625 S = S->getParent(); 626 return S; 627} 628 629void Sema::InitBuiltinVaListType() { 630 if (!Context.getBuiltinVaListType().isNull()) 631 return; 632 633 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 634 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 635 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 636 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 637} 638 639/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 640/// file scope. lazily create a decl for it. ForRedeclaration is true 641/// if we're creating this built-in in anticipation of redeclaring the 642/// built-in. 643NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 644 Scope *S, bool ForRedeclaration, 645 SourceLocation Loc) { 646 Builtin::ID BID = (Builtin::ID)bid; 647 648 if (Context.BuiltinInfo.hasVAListUse(BID)) 649 InitBuiltinVaListType(); 650 651 ASTContext::GetBuiltinTypeError Error; 652 QualType R = Context.GetBuiltinType(BID, Error); 653 switch (Error) { 654 case ASTContext::GE_None: 655 // Okay 656 break; 657 658 case ASTContext::GE_Missing_stdio: 659 if (ForRedeclaration) 660 Diag(Loc, diag::err_implicit_decl_requires_stdio) 661 << Context.BuiltinInfo.GetName(BID); 662 return 0; 663 664 case ASTContext::GE_Missing_setjmp: 665 if (ForRedeclaration) 666 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 667 << Context.BuiltinInfo.GetName(BID); 668 return 0; 669 } 670 671 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 672 Diag(Loc, diag::ext_implicit_lib_function_decl) 673 << Context.BuiltinInfo.GetName(BID) 674 << R; 675 if (Context.BuiltinInfo.getHeaderName(BID) && 676 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 677 != Diagnostic::Ignored) 678 Diag(Loc, diag::note_please_include_header) 679 << Context.BuiltinInfo.getHeaderName(BID) 680 << Context.BuiltinInfo.GetName(BID); 681 } 682 683 FunctionDecl *New = FunctionDecl::Create(Context, 684 Context.getTranslationUnitDecl(), 685 Loc, II, R, /*TInfo=*/0, 686 FunctionDecl::Extern, false, 687 /*hasPrototype=*/true); 688 New->setImplicit(); 689 690 // Create Decl objects for each parameter, adding them to the 691 // FunctionDecl. 692 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 693 llvm::SmallVector<ParmVarDecl*, 16> Params; 694 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 695 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 696 FT->getArgType(i), /*TInfo=*/0, 697 VarDecl::None, 0)); 698 New->setParams(Context, Params.data(), Params.size()); 699 } 700 701 AddKnownFunctionAttributes(New); 702 703 // TUScope is the translation-unit scope to insert this function into. 704 // FIXME: This is hideous. We need to teach PushOnScopeChains to 705 // relate Scopes to DeclContexts, and probably eliminate CurContext 706 // entirely, but we're not there yet. 707 DeclContext *SavedContext = CurContext; 708 CurContext = Context.getTranslationUnitDecl(); 709 PushOnScopeChains(New, TUScope); 710 CurContext = SavedContext; 711 return New; 712} 713 714/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 715/// same name and scope as a previous declaration 'Old'. Figure out 716/// how to resolve this situation, merging decls or emitting 717/// diagnostics as appropriate. If there was an error, set New to be invalid. 718/// 719void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 720 // If the new decl is known invalid already, don't bother doing any 721 // merging checks. 722 if (New->isInvalidDecl()) return; 723 724 // Allow multiple definitions for ObjC built-in typedefs. 725 // FIXME: Verify the underlying types are equivalent! 726 if (getLangOptions().ObjC1) { 727 const IdentifierInfo *TypeID = New->getIdentifier(); 728 switch (TypeID->getLength()) { 729 default: break; 730 case 2: 731 if (!TypeID->isStr("id")) 732 break; 733 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 734 // Install the built-in type for 'id', ignoring the current definition. 735 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 736 return; 737 case 5: 738 if (!TypeID->isStr("Class")) 739 break; 740 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 741 // Install the built-in type for 'Class', ignoring the current definition. 742 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 743 return; 744 case 3: 745 if (!TypeID->isStr("SEL")) 746 break; 747 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 748 // Install the built-in type for 'SEL', ignoring the current definition. 749 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 750 return; 751 case 8: 752 if (!TypeID->isStr("Protocol")) 753 break; 754 Context.setObjCProtoType(New->getUnderlyingType()); 755 return; 756 } 757 // Fall through - the typedef name was not a builtin type. 758 } 759 760 // Verify the old decl was also a type. 761 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 762 if (!Old) { 763 Diag(New->getLocation(), diag::err_redefinition_different_kind) 764 << New->getDeclName(); 765 766 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 767 if (OldD->getLocation().isValid()) 768 Diag(OldD->getLocation(), diag::note_previous_definition); 769 770 return New->setInvalidDecl(); 771 } 772 773 // If the old declaration is invalid, just give up here. 774 if (Old->isInvalidDecl()) 775 return New->setInvalidDecl(); 776 777 // Determine the "old" type we'll use for checking and diagnostics. 778 QualType OldType; 779 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 780 OldType = OldTypedef->getUnderlyingType(); 781 else 782 OldType = Context.getTypeDeclType(Old); 783 784 // If the typedef types are not identical, reject them in all languages and 785 // with any extensions enabled. 786 787 if (OldType != New->getUnderlyingType() && 788 Context.getCanonicalType(OldType) != 789 Context.getCanonicalType(New->getUnderlyingType())) { 790 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 791 << New->getUnderlyingType() << OldType; 792 if (Old->getLocation().isValid()) 793 Diag(Old->getLocation(), diag::note_previous_definition); 794 return New->setInvalidDecl(); 795 } 796 797 // The types match. Link up the redeclaration chain if the old 798 // declaration was a typedef. 799 // FIXME: this is a potential source of wierdness if the type 800 // spellings don't match exactly. 801 if (isa<TypedefDecl>(Old)) 802 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 803 804 if (getLangOptions().Microsoft) 805 return; 806 807 if (getLangOptions().CPlusPlus) { 808 // C++ [dcl.typedef]p2: 809 // In a given non-class scope, a typedef specifier can be used to 810 // redefine the name of any type declared in that scope to refer 811 // to the type to which it already refers. 812 if (!isa<CXXRecordDecl>(CurContext)) 813 return; 814 815 // C++0x [dcl.typedef]p4: 816 // In a given class scope, a typedef specifier can be used to redefine 817 // any class-name declared in that scope that is not also a typedef-name 818 // to refer to the type to which it already refers. 819 // 820 // This wording came in via DR424, which was a correction to the 821 // wording in DR56, which accidentally banned code like: 822 // 823 // struct S { 824 // typedef struct A { } A; 825 // }; 826 // 827 // in the C++03 standard. We implement the C++0x semantics, which 828 // allow the above but disallow 829 // 830 // struct S { 831 // typedef int I; 832 // typedef int I; 833 // }; 834 // 835 // since that was the intent of DR56. 836 if (!isa<TypedefDecl >(Old)) 837 return; 838 839 Diag(New->getLocation(), diag::err_redefinition) 840 << New->getDeclName(); 841 Diag(Old->getLocation(), diag::note_previous_definition); 842 return New->setInvalidDecl(); 843 } 844 845 // If we have a redefinition of a typedef in C, emit a warning. This warning 846 // is normally mapped to an error, but can be controlled with 847 // -Wtypedef-redefinition. If either the original or the redefinition is 848 // in a system header, don't emit this for compatibility with GCC. 849 if (PP.getDiagnostics().getSuppressSystemWarnings() && 850 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 851 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 852 return; 853 854 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 855 << New->getDeclName(); 856 Diag(Old->getLocation(), diag::note_previous_definition); 857 return; 858} 859 860/// DeclhasAttr - returns true if decl Declaration already has the target 861/// attribute. 862static bool 863DeclHasAttr(const Decl *decl, const Attr *target) { 864 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 865 if (attr->getKind() == target->getKind()) 866 return true; 867 868 return false; 869} 870 871/// MergeAttributes - append attributes from the Old decl to the New one. 872static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 873 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 874 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 875 Attr *NewAttr = attr->clone(C); 876 NewAttr->setInherited(true); 877 New->addAttr(NewAttr); 878 } 879 } 880} 881 882/// Used in MergeFunctionDecl to keep track of function parameters in 883/// C. 884struct GNUCompatibleParamWarning { 885 ParmVarDecl *OldParm; 886 ParmVarDecl *NewParm; 887 QualType PromotedType; 888}; 889 890 891/// getSpecialMember - get the special member enum for a method. 892static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 893 const CXXMethodDecl *MD) { 894 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 895 if (Ctor->isDefaultConstructor()) 896 return Sema::CXXDefaultConstructor; 897 if (Ctor->isCopyConstructor()) 898 return Sema::CXXCopyConstructor; 899 } 900 901 if (isa<CXXDestructorDecl>(MD)) 902 return Sema::CXXDestructor; 903 904 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 905 return Sema::CXXCopyAssignment; 906} 907 908/// MergeFunctionDecl - We just parsed a function 'New' from 909/// declarator D which has the same name and scope as a previous 910/// declaration 'Old'. Figure out how to resolve this situation, 911/// merging decls or emitting diagnostics as appropriate. 912/// 913/// In C++, New and Old must be declarations that are not 914/// overloaded. Use IsOverload to determine whether New and Old are 915/// overloaded, and to select the Old declaration that New should be 916/// merged with. 917/// 918/// Returns true if there was an error, false otherwise. 919bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 920 // Verify the old decl was also a function. 921 FunctionDecl *Old = 0; 922 if (FunctionTemplateDecl *OldFunctionTemplate 923 = dyn_cast<FunctionTemplateDecl>(OldD)) 924 Old = OldFunctionTemplate->getTemplatedDecl(); 925 else 926 Old = dyn_cast<FunctionDecl>(OldD); 927 if (!Old) { 928 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 929 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 930 Diag(Shadow->getTargetDecl()->getLocation(), 931 diag::note_using_decl_target); 932 Diag(Shadow->getUsingDecl()->getLocation(), 933 diag::note_using_decl) << 0; 934 return true; 935 } 936 937 Diag(New->getLocation(), diag::err_redefinition_different_kind) 938 << New->getDeclName(); 939 Diag(OldD->getLocation(), diag::note_previous_definition); 940 return true; 941 } 942 943 // Determine whether the previous declaration was a definition, 944 // implicit declaration, or a declaration. 945 diag::kind PrevDiag; 946 if (Old->isThisDeclarationADefinition()) 947 PrevDiag = diag::note_previous_definition; 948 else if (Old->isImplicit()) 949 PrevDiag = diag::note_previous_implicit_declaration; 950 else 951 PrevDiag = diag::note_previous_declaration; 952 953 QualType OldQType = Context.getCanonicalType(Old->getType()); 954 QualType NewQType = Context.getCanonicalType(New->getType()); 955 956 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 957 New->getStorageClass() == FunctionDecl::Static && 958 Old->getStorageClass() != FunctionDecl::Static) { 959 Diag(New->getLocation(), diag::err_static_non_static) 960 << New; 961 Diag(Old->getLocation(), PrevDiag); 962 return true; 963 } 964 965 if (getLangOptions().CPlusPlus) { 966 // (C++98 13.1p2): 967 // Certain function declarations cannot be overloaded: 968 // -- Function declarations that differ only in the return type 969 // cannot be overloaded. 970 QualType OldReturnType 971 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 972 QualType NewReturnType 973 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 974 if (OldReturnType != NewReturnType) { 975 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 976 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 977 return true; 978 } 979 980 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 981 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 982 if (OldMethod && NewMethod) { 983 if (!NewMethod->getFriendObjectKind() && 984 NewMethod->getLexicalDeclContext()->isRecord()) { 985 // -- Member function declarations with the same name and the 986 // same parameter types cannot be overloaded if any of them 987 // is a static member function declaration. 988 if (OldMethod->isStatic() || NewMethod->isStatic()) { 989 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 990 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 991 return true; 992 } 993 994 // C++ [class.mem]p1: 995 // [...] A member shall not be declared twice in the 996 // member-specification, except that a nested class or member 997 // class template can be declared and then later defined. 998 unsigned NewDiag; 999 if (isa<CXXConstructorDecl>(OldMethod)) 1000 NewDiag = diag::err_constructor_redeclared; 1001 else if (isa<CXXDestructorDecl>(NewMethod)) 1002 NewDiag = diag::err_destructor_redeclared; 1003 else if (isa<CXXConversionDecl>(NewMethod)) 1004 NewDiag = diag::err_conv_function_redeclared; 1005 else 1006 NewDiag = diag::err_member_redeclared; 1007 1008 Diag(New->getLocation(), NewDiag); 1009 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1010 } else { 1011 if (OldMethod->isImplicit()) { 1012 Diag(NewMethod->getLocation(), 1013 diag::err_definition_of_implicitly_declared_member) 1014 << New << getSpecialMember(Context, OldMethod); 1015 1016 Diag(OldMethod->getLocation(), 1017 diag::note_previous_implicit_declaration); 1018 return true; 1019 } 1020 } 1021 } 1022 1023 // (C++98 8.3.5p3): 1024 // All declarations for a function shall agree exactly in both the 1025 // return type and the parameter-type-list. 1026 // attributes should be ignored when comparing. 1027 if (Context.getNoReturnType(OldQType, false) == 1028 Context.getNoReturnType(NewQType, false)) 1029 return MergeCompatibleFunctionDecls(New, Old); 1030 1031 // Fall through for conflicting redeclarations and redefinitions. 1032 } 1033 1034 // C: Function types need to be compatible, not identical. This handles 1035 // duplicate function decls like "void f(int); void f(enum X);" properly. 1036 if (!getLangOptions().CPlusPlus && 1037 Context.typesAreCompatible(OldQType, NewQType)) { 1038 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1039 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1040 const FunctionProtoType *OldProto = 0; 1041 if (isa<FunctionNoProtoType>(NewFuncType) && 1042 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1043 // The old declaration provided a function prototype, but the 1044 // new declaration does not. Merge in the prototype. 1045 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1046 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1047 OldProto->arg_type_end()); 1048 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1049 ParamTypes.data(), ParamTypes.size(), 1050 OldProto->isVariadic(), 1051 OldProto->getTypeQuals()); 1052 New->setType(NewQType); 1053 New->setHasInheritedPrototype(); 1054 1055 // Synthesize a parameter for each argument type. 1056 llvm::SmallVector<ParmVarDecl*, 16> Params; 1057 for (FunctionProtoType::arg_type_iterator 1058 ParamType = OldProto->arg_type_begin(), 1059 ParamEnd = OldProto->arg_type_end(); 1060 ParamType != ParamEnd; ++ParamType) { 1061 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1062 SourceLocation(), 0, 1063 *ParamType, /*TInfo=*/0, 1064 VarDecl::None, 0); 1065 Param->setImplicit(); 1066 Params.push_back(Param); 1067 } 1068 1069 New->setParams(Context, Params.data(), Params.size()); 1070 } 1071 1072 return MergeCompatibleFunctionDecls(New, Old); 1073 } 1074 1075 // GNU C permits a K&R definition to follow a prototype declaration 1076 // if the declared types of the parameters in the K&R definition 1077 // match the types in the prototype declaration, even when the 1078 // promoted types of the parameters from the K&R definition differ 1079 // from the types in the prototype. GCC then keeps the types from 1080 // the prototype. 1081 // 1082 // If a variadic prototype is followed by a non-variadic K&R definition, 1083 // the K&R definition becomes variadic. This is sort of an edge case, but 1084 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1085 // C99 6.9.1p8. 1086 if (!getLangOptions().CPlusPlus && 1087 Old->hasPrototype() && !New->hasPrototype() && 1088 New->getType()->getAs<FunctionProtoType>() && 1089 Old->getNumParams() == New->getNumParams()) { 1090 llvm::SmallVector<QualType, 16> ArgTypes; 1091 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1092 const FunctionProtoType *OldProto 1093 = Old->getType()->getAs<FunctionProtoType>(); 1094 const FunctionProtoType *NewProto 1095 = New->getType()->getAs<FunctionProtoType>(); 1096 1097 // Determine whether this is the GNU C extension. 1098 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1099 NewProto->getResultType()); 1100 bool LooseCompatible = !MergedReturn.isNull(); 1101 for (unsigned Idx = 0, End = Old->getNumParams(); 1102 LooseCompatible && Idx != End; ++Idx) { 1103 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1104 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1105 if (Context.typesAreCompatible(OldParm->getType(), 1106 NewProto->getArgType(Idx))) { 1107 ArgTypes.push_back(NewParm->getType()); 1108 } else if (Context.typesAreCompatible(OldParm->getType(), 1109 NewParm->getType())) { 1110 GNUCompatibleParamWarning Warn 1111 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1112 Warnings.push_back(Warn); 1113 ArgTypes.push_back(NewParm->getType()); 1114 } else 1115 LooseCompatible = false; 1116 } 1117 1118 if (LooseCompatible) { 1119 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1120 Diag(Warnings[Warn].NewParm->getLocation(), 1121 diag::ext_param_promoted_not_compatible_with_prototype) 1122 << Warnings[Warn].PromotedType 1123 << Warnings[Warn].OldParm->getType(); 1124 Diag(Warnings[Warn].OldParm->getLocation(), 1125 diag::note_previous_declaration); 1126 } 1127 1128 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1129 ArgTypes.size(), 1130 OldProto->isVariadic(), 0)); 1131 return MergeCompatibleFunctionDecls(New, Old); 1132 } 1133 1134 // Fall through to diagnose conflicting types. 1135 } 1136 1137 // A function that has already been declared has been redeclared or defined 1138 // with a different type- show appropriate diagnostic 1139 if (unsigned BuiltinID = Old->getBuiltinID()) { 1140 // The user has declared a builtin function with an incompatible 1141 // signature. 1142 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1143 // The function the user is redeclaring is a library-defined 1144 // function like 'malloc' or 'printf'. Warn about the 1145 // redeclaration, then pretend that we don't know about this 1146 // library built-in. 1147 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1148 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1149 << Old << Old->getType(); 1150 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1151 Old->setInvalidDecl(); 1152 return false; 1153 } 1154 1155 PrevDiag = diag::note_previous_builtin_declaration; 1156 } 1157 1158 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1159 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1160 return true; 1161} 1162 1163/// \brief Completes the merge of two function declarations that are 1164/// known to be compatible. 1165/// 1166/// This routine handles the merging of attributes and other 1167/// properties of function declarations form the old declaration to 1168/// the new declaration, once we know that New is in fact a 1169/// redeclaration of Old. 1170/// 1171/// \returns false 1172bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1173 // Merge the attributes 1174 MergeAttributes(New, Old, Context); 1175 1176 // Merge the storage class. 1177 if (Old->getStorageClass() != FunctionDecl::Extern && 1178 Old->getStorageClass() != FunctionDecl::None) 1179 New->setStorageClass(Old->getStorageClass()); 1180 1181 // Merge "pure" flag. 1182 if (Old->isPure()) 1183 New->setPure(); 1184 1185 // Merge the "deleted" flag. 1186 if (Old->isDeleted()) 1187 New->setDeleted(); 1188 1189 if (getLangOptions().CPlusPlus) 1190 return MergeCXXFunctionDecl(New, Old); 1191 1192 return false; 1193} 1194 1195/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1196/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1197/// situation, merging decls or emitting diagnostics as appropriate. 1198/// 1199/// Tentative definition rules (C99 6.9.2p2) are checked by 1200/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1201/// definitions here, since the initializer hasn't been attached. 1202/// 1203void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1204 // If the new decl is already invalid, don't do any other checking. 1205 if (New->isInvalidDecl()) 1206 return; 1207 1208 // Verify the old decl was also a variable. 1209 VarDecl *Old = 0; 1210 if (!Previous.isSingleResult() || 1211 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1212 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1213 << New->getDeclName(); 1214 Diag(Previous.getRepresentativeDecl()->getLocation(), 1215 diag::note_previous_definition); 1216 return New->setInvalidDecl(); 1217 } 1218 1219 MergeAttributes(New, Old, Context); 1220 1221 // Merge the types 1222 QualType MergedT; 1223 if (getLangOptions().CPlusPlus) { 1224 if (Context.hasSameType(New->getType(), Old->getType())) 1225 MergedT = New->getType(); 1226 // C++ [basic.link]p10: 1227 // [...] the types specified by all declarations referring to a given 1228 // object or function shall be identical, except that declarations for an 1229 // array object can specify array types that differ by the presence or 1230 // absence of a major array bound (8.3.4). 1231 else if (Old->getType()->isIncompleteArrayType() && 1232 New->getType()->isArrayType()) { 1233 CanQual<ArrayType> OldArray 1234 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1235 CanQual<ArrayType> NewArray 1236 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1237 if (OldArray->getElementType() == NewArray->getElementType()) 1238 MergedT = New->getType(); 1239 } else if (Old->getType()->isArrayType() && 1240 New->getType()->isIncompleteArrayType()) { 1241 CanQual<ArrayType> OldArray 1242 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1243 CanQual<ArrayType> NewArray 1244 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1245 if (OldArray->getElementType() == NewArray->getElementType()) 1246 MergedT = Old->getType(); 1247 } 1248 } else { 1249 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1250 } 1251 if (MergedT.isNull()) { 1252 Diag(New->getLocation(), diag::err_redefinition_different_type) 1253 << New->getDeclName(); 1254 Diag(Old->getLocation(), diag::note_previous_definition); 1255 return New->setInvalidDecl(); 1256 } 1257 New->setType(MergedT); 1258 1259 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1260 if (New->getStorageClass() == VarDecl::Static && 1261 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1262 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1263 Diag(Old->getLocation(), diag::note_previous_definition); 1264 return New->setInvalidDecl(); 1265 } 1266 // C99 6.2.2p4: 1267 // For an identifier declared with the storage-class specifier 1268 // extern in a scope in which a prior declaration of that 1269 // identifier is visible,23) if the prior declaration specifies 1270 // internal or external linkage, the linkage of the identifier at 1271 // the later declaration is the same as the linkage specified at 1272 // the prior declaration. If no prior declaration is visible, or 1273 // if the prior declaration specifies no linkage, then the 1274 // identifier has external linkage. 1275 if (New->hasExternalStorage() && Old->hasLinkage()) 1276 /* Okay */; 1277 else if (New->getStorageClass() != VarDecl::Static && 1278 Old->getStorageClass() == VarDecl::Static) { 1279 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1280 Diag(Old->getLocation(), diag::note_previous_definition); 1281 return New->setInvalidDecl(); 1282 } 1283 1284 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1285 1286 // FIXME: The test for external storage here seems wrong? We still 1287 // need to check for mismatches. 1288 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1289 // Don't complain about out-of-line definitions of static members. 1290 !(Old->getLexicalDeclContext()->isRecord() && 1291 !New->getLexicalDeclContext()->isRecord())) { 1292 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1293 Diag(Old->getLocation(), diag::note_previous_definition); 1294 return New->setInvalidDecl(); 1295 } 1296 1297 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1298 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1299 Diag(Old->getLocation(), diag::note_previous_definition); 1300 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1301 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1302 Diag(Old->getLocation(), diag::note_previous_definition); 1303 } 1304 1305 // Keep a chain of previous declarations. 1306 New->setPreviousDeclaration(Old); 1307} 1308 1309static void MarkLive(CFGBlock *e, llvm::BitVector &live) { 1310 std::queue<CFGBlock*> workq; 1311 // Prep work queue 1312 workq.push(e); 1313 // Solve 1314 while (!workq.empty()) { 1315 CFGBlock *item = workq.front(); 1316 workq.pop(); 1317 live.set(item->getBlockID()); 1318 for (CFGBlock::succ_iterator I=item->succ_begin(), 1319 E=item->succ_end(); 1320 I != E; 1321 ++I) { 1322 if ((*I) && !live[(*I)->getBlockID()]) { 1323 live.set((*I)->getBlockID()); 1324 workq.push(*I); 1325 } 1326 } 1327 } 1328} 1329 1330/// CheckUnreachable - Check for unreachable code. 1331void Sema::CheckUnreachable(AnalysisContext &AC) { 1332 // We avoid checking when there are errors, as the CFG won't faithfully match 1333 // the user's code. 1334 if (getDiagnostics().hasErrorOccurred()) 1335 return; 1336 if (Diags.getDiagnosticLevel(diag::warn_unreachable) == Diagnostic::Ignored) 1337 return; 1338 1339 CFG *cfg = AC.getCFG(); 1340 if (cfg == 0) 1341 return; 1342 1343 llvm::BitVector live(cfg->getNumBlockIDs()); 1344 // Mark all live things first. 1345 MarkLive(&cfg->getEntry(), live); 1346 1347 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1348 CFGBlock &b = **I; 1349 if (!live[b.getBlockID()]) { 1350 if (!b.empty()) 1351 Diag(b[0].getStmt()->getLocStart(), diag::warn_unreachable); 1352 // Avoid excessive errors by marking everything reachable from here 1353 MarkLive(&b, live); 1354 } 1355 } 1356} 1357 1358/// CheckFallThrough - Check that we don't fall off the end of a 1359/// Statement that should return a value. 1360/// 1361/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1362/// MaybeFallThrough iff we might or might not fall off the end, 1363/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1364/// return. We assume NeverFallThrough iff we never fall off the end of the 1365/// statement but we may return. We assume that functions not marked noreturn 1366/// will return. 1367Sema::ControlFlowKind Sema::CheckFallThrough(AnalysisContext &AC) { 1368 CFG *cfg = AC.getCFG(); 1369 if (cfg == 0) 1370 // FIXME: This should be NeverFallThrough 1371 return NeverFallThroughOrReturn; 1372 1373 // The CFG leaves in dead things, and we don't want to dead code paths to 1374 // confuse us, so we mark all live things first. 1375 std::queue<CFGBlock*> workq; 1376 llvm::BitVector live(cfg->getNumBlockIDs()); 1377 MarkLive(&cfg->getEntry(), live); 1378 1379 // Now we know what is live, we check the live precessors of the exit block 1380 // and look for fall through paths, being careful to ignore normal returns, 1381 // and exceptional paths. 1382 bool HasLiveReturn = false; 1383 bool HasFakeEdge = false; 1384 bool HasPlainEdge = false; 1385 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1386 E = cfg->getExit().pred_end(); 1387 I != E; 1388 ++I) { 1389 CFGBlock& B = **I; 1390 if (!live[B.getBlockID()]) 1391 continue; 1392 if (B.size() == 0) { 1393 // A labeled empty statement, or the entry block... 1394 HasPlainEdge = true; 1395 continue; 1396 } 1397 Stmt *S = B[B.size()-1]; 1398 if (isa<ReturnStmt>(S)) { 1399 HasLiveReturn = true; 1400 continue; 1401 } 1402 if (isa<ObjCAtThrowStmt>(S)) { 1403 HasFakeEdge = true; 1404 continue; 1405 } 1406 if (isa<CXXThrowExpr>(S)) { 1407 HasFakeEdge = true; 1408 continue; 1409 } 1410 if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) { 1411 if (AS->isMSAsm()) { 1412 HasFakeEdge = true; 1413 HasLiveReturn = true; 1414 continue; 1415 } 1416 } 1417 1418 bool NoReturnEdge = false; 1419 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1420 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1421 if (CEE->getType().getNoReturnAttr()) { 1422 NoReturnEdge = true; 1423 HasFakeEdge = true; 1424 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1425 ValueDecl *VD = DRE->getDecl(); 1426 if (VD->hasAttr<NoReturnAttr>()) { 1427 NoReturnEdge = true; 1428 HasFakeEdge = true; 1429 } 1430 } 1431 } 1432 // FIXME: Add noreturn message sends. 1433 if (NoReturnEdge == false) 1434 HasPlainEdge = true; 1435 } 1436 if (!HasPlainEdge) { 1437 if (HasLiveReturn) 1438 return NeverFallThrough; 1439 return NeverFallThroughOrReturn; 1440 } 1441 if (HasFakeEdge || HasLiveReturn) 1442 return MaybeFallThrough; 1443 // This says AlwaysFallThrough for calls to functions that are not marked 1444 // noreturn, that don't return. If people would like this warning to be more 1445 // accurate, such functions should be marked as noreturn. 1446 return AlwaysFallThrough; 1447} 1448 1449/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1450/// function that should return a value. Check that we don't fall off the end 1451/// of a noreturn function. We assume that functions and blocks not marked 1452/// noreturn will return. 1453void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body, 1454 AnalysisContext &AC) { 1455 // FIXME: Would be nice if we had a better way to control cascading errors, 1456 // but for now, avoid them. The problem is that when Parse sees: 1457 // int foo() { return a; } 1458 // The return is eaten and the Sema code sees just: 1459 // int foo() { } 1460 // which this code would then warn about. 1461 if (getDiagnostics().hasErrorOccurred()) 1462 return; 1463 1464 bool ReturnsVoid = false; 1465 bool HasNoReturn = false; 1466 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1467 // If the result type of the function is a dependent type, we don't know 1468 // whether it will be void or not, so don't 1469 if (FD->getResultType()->isDependentType()) 1470 return; 1471 if (FD->getResultType()->isVoidType()) 1472 ReturnsVoid = true; 1473 if (FD->hasAttr<NoReturnAttr>()) 1474 HasNoReturn = true; 1475 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1476 if (MD->getResultType()->isVoidType()) 1477 ReturnsVoid = true; 1478 if (MD->hasAttr<NoReturnAttr>()) 1479 HasNoReturn = true; 1480 } 1481 1482 // Short circuit for compilation speed. 1483 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1484 == Diagnostic::Ignored || ReturnsVoid) 1485 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1486 == Diagnostic::Ignored || !HasNoReturn) 1487 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1488 == Diagnostic::Ignored || !ReturnsVoid)) 1489 return; 1490 // FIXME: Function try block 1491 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1492 switch (CheckFallThrough(AC)) { 1493 case MaybeFallThrough: 1494 if (HasNoReturn) 1495 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1496 else if (!ReturnsVoid) 1497 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1498 break; 1499 case AlwaysFallThrough: 1500 if (HasNoReturn) 1501 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1502 else if (!ReturnsVoid) 1503 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1504 break; 1505 case NeverFallThroughOrReturn: 1506 if (ReturnsVoid && !HasNoReturn) 1507 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1508 break; 1509 case NeverFallThrough: 1510 break; 1511 } 1512 } 1513} 1514 1515/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1516/// that should return a value. Check that we don't fall off the end of a 1517/// noreturn block. We assume that functions and blocks not marked noreturn 1518/// will return. 1519void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body, 1520 AnalysisContext &AC) { 1521 // FIXME: Would be nice if we had a better way to control cascading errors, 1522 // but for now, avoid them. The problem is that when Parse sees: 1523 // int foo() { return a; } 1524 // The return is eaten and the Sema code sees just: 1525 // int foo() { } 1526 // which this code would then warn about. 1527 if (getDiagnostics().hasErrorOccurred()) 1528 return; 1529 bool ReturnsVoid = false; 1530 bool HasNoReturn = false; 1531 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1532 if (FT->getResultType()->isVoidType()) 1533 ReturnsVoid = true; 1534 if (FT->getNoReturnAttr()) 1535 HasNoReturn = true; 1536 } 1537 1538 // Short circuit for compilation speed. 1539 if (ReturnsVoid 1540 && !HasNoReturn 1541 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1542 == Diagnostic::Ignored || !ReturnsVoid)) 1543 return; 1544 // FIXME: Funtion try block 1545 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1546 switch (CheckFallThrough(AC)) { 1547 case MaybeFallThrough: 1548 if (HasNoReturn) 1549 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1550 else if (!ReturnsVoid) 1551 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1552 break; 1553 case AlwaysFallThrough: 1554 if (HasNoReturn) 1555 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1556 else if (!ReturnsVoid) 1557 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1558 break; 1559 case NeverFallThroughOrReturn: 1560 if (ReturnsVoid) 1561 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1562 break; 1563 case NeverFallThrough: 1564 break; 1565 } 1566 } 1567} 1568 1569/// CheckParmsForFunctionDef - Check that the parameters of the given 1570/// function are appropriate for the definition of a function. This 1571/// takes care of any checks that cannot be performed on the 1572/// declaration itself, e.g., that the types of each of the function 1573/// parameters are complete. 1574bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1575 bool HasInvalidParm = false; 1576 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1577 ParmVarDecl *Param = FD->getParamDecl(p); 1578 1579 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1580 // function declarator that is part of a function definition of 1581 // that function shall not have incomplete type. 1582 // 1583 // This is also C++ [dcl.fct]p6. 1584 if (!Param->isInvalidDecl() && 1585 RequireCompleteType(Param->getLocation(), Param->getType(), 1586 diag::err_typecheck_decl_incomplete_type)) { 1587 Param->setInvalidDecl(); 1588 HasInvalidParm = true; 1589 } 1590 1591 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1592 // declaration of each parameter shall include an identifier. 1593 if (Param->getIdentifier() == 0 && 1594 !Param->isImplicit() && 1595 !getLangOptions().CPlusPlus) 1596 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1597 } 1598 1599 return HasInvalidParm; 1600} 1601 1602/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1603/// no declarator (e.g. "struct foo;") is parsed. 1604Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1605 // FIXME: Error on auto/register at file scope 1606 // FIXME: Error on inline/virtual/explicit 1607 // FIXME: Warn on useless __thread 1608 // FIXME: Warn on useless const/volatile 1609 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1610 // FIXME: Warn on useless attributes 1611 Decl *TagD = 0; 1612 TagDecl *Tag = 0; 1613 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1614 DS.getTypeSpecType() == DeclSpec::TST_struct || 1615 DS.getTypeSpecType() == DeclSpec::TST_union || 1616 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1617 TagD = static_cast<Decl *>(DS.getTypeRep()); 1618 1619 if (!TagD) // We probably had an error 1620 return DeclPtrTy(); 1621 1622 // Note that the above type specs guarantee that the 1623 // type rep is a Decl, whereas in many of the others 1624 // it's a Type. 1625 Tag = dyn_cast<TagDecl>(TagD); 1626 } 1627 1628 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1629 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1630 // or incomplete types shall not be restrict-qualified." 1631 if (TypeQuals & DeclSpec::TQ_restrict) 1632 Diag(DS.getRestrictSpecLoc(), 1633 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1634 << DS.getSourceRange(); 1635 } 1636 1637 if (DS.isFriendSpecified()) { 1638 // If we're dealing with a class template decl, assume that the 1639 // template routines are handling it. 1640 if (TagD && isa<ClassTemplateDecl>(TagD)) 1641 return DeclPtrTy(); 1642 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1643 } 1644 1645 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1646 // If there are attributes in the DeclSpec, apply them to the record. 1647 if (const AttributeList *AL = DS.getAttributes()) 1648 ProcessDeclAttributeList(S, Record, AL); 1649 1650 if (!Record->getDeclName() && Record->isDefinition() && 1651 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1652 if (getLangOptions().CPlusPlus || 1653 Record->getDeclContext()->isRecord()) 1654 return BuildAnonymousStructOrUnion(S, DS, Record); 1655 1656 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1657 << DS.getSourceRange(); 1658 } 1659 1660 // Microsoft allows unnamed struct/union fields. Don't complain 1661 // about them. 1662 // FIXME: Should we support Microsoft's extensions in this area? 1663 if (Record->getDeclName() && getLangOptions().Microsoft) 1664 return DeclPtrTy::make(Tag); 1665 } 1666 1667 if (!DS.isMissingDeclaratorOk() && 1668 DS.getTypeSpecType() != DeclSpec::TST_error) { 1669 // Warn about typedefs of enums without names, since this is an 1670 // extension in both Microsoft an GNU. 1671 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1672 Tag && isa<EnumDecl>(Tag)) { 1673 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1674 << DS.getSourceRange(); 1675 return DeclPtrTy::make(Tag); 1676 } 1677 1678 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1679 << DS.getSourceRange(); 1680 return DeclPtrTy(); 1681 } 1682 1683 return DeclPtrTy::make(Tag); 1684} 1685 1686/// We are trying to inject an anonymous member into the given scope; 1687/// check if there's an existing declaration that can't be overloaded. 1688/// 1689/// \return true if this is a forbidden redeclaration 1690static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1691 Scope *S, 1692 DeclarationName Name, 1693 SourceLocation NameLoc, 1694 unsigned diagnostic) { 1695 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1696 Sema::ForRedeclaration); 1697 if (!SemaRef.LookupName(R, S)) return false; 1698 1699 if (R.getAsSingle<TagDecl>()) 1700 return false; 1701 1702 // Pick a representative declaration. 1703 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1704 1705 SemaRef.Diag(NameLoc, diagnostic) << Name; 1706 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1707 1708 return true; 1709} 1710 1711/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1712/// anonymous struct or union AnonRecord into the owning context Owner 1713/// and scope S. This routine will be invoked just after we realize 1714/// that an unnamed union or struct is actually an anonymous union or 1715/// struct, e.g., 1716/// 1717/// @code 1718/// union { 1719/// int i; 1720/// float f; 1721/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1722/// // f into the surrounding scope.x 1723/// @endcode 1724/// 1725/// This routine is recursive, injecting the names of nested anonymous 1726/// structs/unions into the owning context and scope as well. 1727bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1728 RecordDecl *AnonRecord) { 1729 unsigned diagKind 1730 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1731 : diag::err_anonymous_struct_member_redecl; 1732 1733 bool Invalid = false; 1734 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1735 FEnd = AnonRecord->field_end(); 1736 F != FEnd; ++F) { 1737 if ((*F)->getDeclName()) { 1738 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1739 (*F)->getLocation(), diagKind)) { 1740 // C++ [class.union]p2: 1741 // The names of the members of an anonymous union shall be 1742 // distinct from the names of any other entity in the 1743 // scope in which the anonymous union is declared. 1744 Invalid = true; 1745 } else { 1746 // C++ [class.union]p2: 1747 // For the purpose of name lookup, after the anonymous union 1748 // definition, the members of the anonymous union are 1749 // considered to have been defined in the scope in which the 1750 // anonymous union is declared. 1751 Owner->makeDeclVisibleInContext(*F); 1752 S->AddDecl(DeclPtrTy::make(*F)); 1753 IdResolver.AddDecl(*F); 1754 } 1755 } else if (const RecordType *InnerRecordType 1756 = (*F)->getType()->getAs<RecordType>()) { 1757 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1758 if (InnerRecord->isAnonymousStructOrUnion()) 1759 Invalid = Invalid || 1760 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1761 } 1762 } 1763 1764 return Invalid; 1765} 1766 1767/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1768/// anonymous structure or union. Anonymous unions are a C++ feature 1769/// (C++ [class.union]) and a GNU C extension; anonymous structures 1770/// are a GNU C and GNU C++ extension. 1771Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1772 RecordDecl *Record) { 1773 DeclContext *Owner = Record->getDeclContext(); 1774 1775 // Diagnose whether this anonymous struct/union is an extension. 1776 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1777 Diag(Record->getLocation(), diag::ext_anonymous_union); 1778 else if (!Record->isUnion()) 1779 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1780 1781 // C and C++ require different kinds of checks for anonymous 1782 // structs/unions. 1783 bool Invalid = false; 1784 if (getLangOptions().CPlusPlus) { 1785 const char* PrevSpec = 0; 1786 unsigned DiagID; 1787 // C++ [class.union]p3: 1788 // Anonymous unions declared in a named namespace or in the 1789 // global namespace shall be declared static. 1790 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1791 (isa<TranslationUnitDecl>(Owner) || 1792 (isa<NamespaceDecl>(Owner) && 1793 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1794 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1795 Invalid = true; 1796 1797 // Recover by adding 'static'. 1798 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1799 PrevSpec, DiagID); 1800 } 1801 // C++ [class.union]p3: 1802 // A storage class is not allowed in a declaration of an 1803 // anonymous union in a class scope. 1804 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1805 isa<RecordDecl>(Owner)) { 1806 Diag(DS.getStorageClassSpecLoc(), 1807 diag::err_anonymous_union_with_storage_spec); 1808 Invalid = true; 1809 1810 // Recover by removing the storage specifier. 1811 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1812 PrevSpec, DiagID); 1813 } 1814 1815 // C++ [class.union]p2: 1816 // The member-specification of an anonymous union shall only 1817 // define non-static data members. [Note: nested types and 1818 // functions cannot be declared within an anonymous union. ] 1819 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1820 MemEnd = Record->decls_end(); 1821 Mem != MemEnd; ++Mem) { 1822 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1823 // C++ [class.union]p3: 1824 // An anonymous union shall not have private or protected 1825 // members (clause 11). 1826 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1827 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1828 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1829 Invalid = true; 1830 } 1831 } else if ((*Mem)->isImplicit()) { 1832 // Any implicit members are fine. 1833 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1834 // This is a type that showed up in an 1835 // elaborated-type-specifier inside the anonymous struct or 1836 // union, but which actually declares a type outside of the 1837 // anonymous struct or union. It's okay. 1838 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1839 if (!MemRecord->isAnonymousStructOrUnion() && 1840 MemRecord->getDeclName()) { 1841 // This is a nested type declaration. 1842 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1843 << (int)Record->isUnion(); 1844 Invalid = true; 1845 } 1846 } else { 1847 // We have something that isn't a non-static data 1848 // member. Complain about it. 1849 unsigned DK = diag::err_anonymous_record_bad_member; 1850 if (isa<TypeDecl>(*Mem)) 1851 DK = diag::err_anonymous_record_with_type; 1852 else if (isa<FunctionDecl>(*Mem)) 1853 DK = diag::err_anonymous_record_with_function; 1854 else if (isa<VarDecl>(*Mem)) 1855 DK = diag::err_anonymous_record_with_static; 1856 Diag((*Mem)->getLocation(), DK) 1857 << (int)Record->isUnion(); 1858 Invalid = true; 1859 } 1860 } 1861 } 1862 1863 if (!Record->isUnion() && !Owner->isRecord()) { 1864 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1865 << (int)getLangOptions().CPlusPlus; 1866 Invalid = true; 1867 } 1868 1869 // Mock up a declarator. 1870 Declarator Dc(DS, Declarator::TypeNameContext); 1871 TypeSourceInfo *TInfo = 0; 1872 GetTypeForDeclarator(Dc, S, &TInfo); 1873 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1874 1875 // Create a declaration for this anonymous struct/union. 1876 NamedDecl *Anon = 0; 1877 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1878 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1879 /*IdentifierInfo=*/0, 1880 Context.getTypeDeclType(Record), 1881 TInfo, 1882 /*BitWidth=*/0, /*Mutable=*/false); 1883 Anon->setAccess(AS_public); 1884 if (getLangOptions().CPlusPlus) 1885 FieldCollector->Add(cast<FieldDecl>(Anon)); 1886 } else { 1887 VarDecl::StorageClass SC; 1888 switch (DS.getStorageClassSpec()) { 1889 default: assert(0 && "Unknown storage class!"); 1890 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1891 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1892 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1893 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1894 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1895 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1896 case DeclSpec::SCS_mutable: 1897 // mutable can only appear on non-static class members, so it's always 1898 // an error here 1899 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1900 Invalid = true; 1901 SC = VarDecl::None; 1902 break; 1903 } 1904 1905 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1906 /*IdentifierInfo=*/0, 1907 Context.getTypeDeclType(Record), 1908 TInfo, 1909 SC); 1910 } 1911 Anon->setImplicit(); 1912 1913 // Add the anonymous struct/union object to the current 1914 // context. We'll be referencing this object when we refer to one of 1915 // its members. 1916 Owner->addDecl(Anon); 1917 1918 // Inject the members of the anonymous struct/union into the owning 1919 // context and into the identifier resolver chain for name lookup 1920 // purposes. 1921 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1922 Invalid = true; 1923 1924 // Mark this as an anonymous struct/union type. Note that we do not 1925 // do this until after we have already checked and injected the 1926 // members of this anonymous struct/union type, because otherwise 1927 // the members could be injected twice: once by DeclContext when it 1928 // builds its lookup table, and once by 1929 // InjectAnonymousStructOrUnionMembers. 1930 Record->setAnonymousStructOrUnion(true); 1931 1932 if (Invalid) 1933 Anon->setInvalidDecl(); 1934 1935 return DeclPtrTy::make(Anon); 1936} 1937 1938 1939/// GetNameForDeclarator - Determine the full declaration name for the 1940/// given Declarator. 1941DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1942 return GetNameFromUnqualifiedId(D.getName()); 1943} 1944 1945/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1946DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1947 switch (Name.getKind()) { 1948 case UnqualifiedId::IK_Identifier: 1949 return DeclarationName(Name.Identifier); 1950 1951 case UnqualifiedId::IK_OperatorFunctionId: 1952 return Context.DeclarationNames.getCXXOperatorName( 1953 Name.OperatorFunctionId.Operator); 1954 1955 case UnqualifiedId::IK_LiteralOperatorId: 1956 return Context.DeclarationNames.getCXXLiteralOperatorName( 1957 Name.Identifier); 1958 1959 case UnqualifiedId::IK_ConversionFunctionId: { 1960 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1961 if (Ty.isNull()) 1962 return DeclarationName(); 1963 1964 return Context.DeclarationNames.getCXXConversionFunctionName( 1965 Context.getCanonicalType(Ty)); 1966 } 1967 1968 case UnqualifiedId::IK_ConstructorName: { 1969 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1970 if (Ty.isNull()) 1971 return DeclarationName(); 1972 1973 return Context.DeclarationNames.getCXXConstructorName( 1974 Context.getCanonicalType(Ty)); 1975 } 1976 1977 case UnqualifiedId::IK_ConstructorTemplateId: { 1978 // In well-formed code, we can only have a constructor 1979 // template-id that refers to the current context, so go there 1980 // to find the actual type being constructed. 1981 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1982 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1983 return DeclarationName(); 1984 1985 // Determine the type of the class being constructed. 1986 QualType CurClassType; 1987 if (ClassTemplateDecl *ClassTemplate 1988 = CurClass->getDescribedClassTemplate()) 1989 CurClassType = ClassTemplate->getInjectedClassNameType(Context); 1990 else 1991 CurClassType = Context.getTypeDeclType(CurClass); 1992 1993 // FIXME: Check two things: that the template-id names the same type as 1994 // CurClassType, and that the template-id does not occur when the name 1995 // was qualified. 1996 1997 return Context.DeclarationNames.getCXXConstructorName( 1998 Context.getCanonicalType(CurClassType)); 1999 } 2000 2001 case UnqualifiedId::IK_DestructorName: { 2002 QualType Ty = GetTypeFromParser(Name.DestructorName); 2003 if (Ty.isNull()) 2004 return DeclarationName(); 2005 2006 return Context.DeclarationNames.getCXXDestructorName( 2007 Context.getCanonicalType(Ty)); 2008 } 2009 2010 case UnqualifiedId::IK_TemplateId: { 2011 TemplateName TName 2012 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2013 return Context.getNameForTemplate(TName); 2014 } 2015 } 2016 2017 assert(false && "Unknown name kind"); 2018 return DeclarationName(); 2019} 2020 2021/// isNearlyMatchingFunction - Determine whether the C++ functions 2022/// Declaration and Definition are "nearly" matching. This heuristic 2023/// is used to improve diagnostics in the case where an out-of-line 2024/// function definition doesn't match any declaration within 2025/// the class or namespace. 2026static bool isNearlyMatchingFunction(ASTContext &Context, 2027 FunctionDecl *Declaration, 2028 FunctionDecl *Definition) { 2029 if (Declaration->param_size() != Definition->param_size()) 2030 return false; 2031 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2032 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2033 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2034 2035 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2036 DefParamTy.getNonReferenceType())) 2037 return false; 2038 } 2039 2040 return true; 2041} 2042 2043Sema::DeclPtrTy 2044Sema::HandleDeclarator(Scope *S, Declarator &D, 2045 MultiTemplateParamsArg TemplateParamLists, 2046 bool IsFunctionDefinition) { 2047 DeclarationName Name = GetNameForDeclarator(D); 2048 2049 // All of these full declarators require an identifier. If it doesn't have 2050 // one, the ParsedFreeStandingDeclSpec action should be used. 2051 if (!Name) { 2052 if (!D.isInvalidType()) // Reject this if we think it is valid. 2053 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2054 diag::err_declarator_need_ident) 2055 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2056 return DeclPtrTy(); 2057 } 2058 2059 // The scope passed in may not be a decl scope. Zip up the scope tree until 2060 // we find one that is. 2061 while ((S->getFlags() & Scope::DeclScope) == 0 || 2062 (S->getFlags() & Scope::TemplateParamScope) != 0) 2063 S = S->getParent(); 2064 2065 // If this is an out-of-line definition of a member of a class template 2066 // or class template partial specialization, we may need to rebuild the 2067 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 2068 // for more information. 2069 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 2070 // handle expressions properly. 2071 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 2072 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 2073 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 2074 (DS.getTypeSpecType() == DeclSpec::TST_typename || 2075 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 2076 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 2077 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 2078 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 2079 // FIXME: Preserve type source info. 2080 QualType T = GetTypeFromParser(DS.getTypeRep()); 2081 2082 DeclContext *SavedContext = CurContext; 2083 CurContext = DC; 2084 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 2085 CurContext = SavedContext; 2086 2087 if (T.isNull()) 2088 return DeclPtrTy(); 2089 DS.UpdateTypeRep(T.getAsOpaquePtr()); 2090 } 2091 } 2092 2093 DeclContext *DC; 2094 NamedDecl *New; 2095 2096 TypeSourceInfo *TInfo = 0; 2097 QualType R = GetTypeForDeclarator(D, S, &TInfo); 2098 2099 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2100 ForRedeclaration); 2101 2102 // See if this is a redefinition of a variable in the same scope. 2103 if (D.getCXXScopeSpec().isInvalid()) { 2104 DC = CurContext; 2105 D.setInvalidType(); 2106 } else if (!D.getCXXScopeSpec().isSet()) { 2107 bool IsLinkageLookup = false; 2108 2109 // If the declaration we're planning to build will be a function 2110 // or object with linkage, then look for another declaration with 2111 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2112 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2113 /* Do nothing*/; 2114 else if (R->isFunctionType()) { 2115 if (CurContext->isFunctionOrMethod() || 2116 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2117 IsLinkageLookup = true; 2118 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2119 IsLinkageLookup = true; 2120 else if (CurContext->getLookupContext()->isTranslationUnit() && 2121 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2122 IsLinkageLookup = true; 2123 2124 if (IsLinkageLookup) 2125 Previous.clear(LookupRedeclarationWithLinkage); 2126 2127 DC = CurContext; 2128 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2129 } else { // Something like "int foo::x;" 2130 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2131 2132 if (!DC) { 2133 // If we could not compute the declaration context, it's because the 2134 // declaration context is dependent but does not refer to a class, 2135 // class template, or class template partial specialization. Complain 2136 // and return early, to avoid the coming semantic disaster. 2137 Diag(D.getIdentifierLoc(), 2138 diag::err_template_qualified_declarator_no_match) 2139 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2140 << D.getCXXScopeSpec().getRange(); 2141 return DeclPtrTy(); 2142 } 2143 2144 if (!DC->isDependentContext() && 2145 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2146 return DeclPtrTy(); 2147 2148 LookupQualifiedName(Previous, DC); 2149 2150 // Don't consider using declarations as previous declarations for 2151 // out-of-line members. 2152 RemoveUsingDecls(Previous); 2153 2154 // C++ 7.3.1.2p2: 2155 // Members (including explicit specializations of templates) of a named 2156 // namespace can also be defined outside that namespace by explicit 2157 // qualification of the name being defined, provided that the entity being 2158 // defined was already declared in the namespace and the definition appears 2159 // after the point of declaration in a namespace that encloses the 2160 // declarations namespace. 2161 // 2162 // Note that we only check the context at this point. We don't yet 2163 // have enough information to make sure that PrevDecl is actually 2164 // the declaration we want to match. For example, given: 2165 // 2166 // class X { 2167 // void f(); 2168 // void f(float); 2169 // }; 2170 // 2171 // void X::f(int) { } // ill-formed 2172 // 2173 // In this case, PrevDecl will point to the overload set 2174 // containing the two f's declared in X, but neither of them 2175 // matches. 2176 2177 // First check whether we named the global scope. 2178 if (isa<TranslationUnitDecl>(DC)) { 2179 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2180 << Name << D.getCXXScopeSpec().getRange(); 2181 } else { 2182 DeclContext *Cur = CurContext; 2183 while (isa<LinkageSpecDecl>(Cur)) 2184 Cur = Cur->getParent(); 2185 if (!Cur->Encloses(DC)) { 2186 // The qualifying scope doesn't enclose the original declaration. 2187 // Emit diagnostic based on current scope. 2188 SourceLocation L = D.getIdentifierLoc(); 2189 SourceRange R = D.getCXXScopeSpec().getRange(); 2190 if (isa<FunctionDecl>(Cur)) 2191 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2192 else 2193 Diag(L, diag::err_invalid_declarator_scope) 2194 << Name << cast<NamedDecl>(DC) << R; 2195 D.setInvalidType(); 2196 } 2197 } 2198 } 2199 2200 if (Previous.isSingleResult() && 2201 Previous.getFoundDecl()->isTemplateParameter()) { 2202 // Maybe we will complain about the shadowed template parameter. 2203 if (!D.isInvalidType()) 2204 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2205 Previous.getFoundDecl())) 2206 D.setInvalidType(); 2207 2208 // Just pretend that we didn't see the previous declaration. 2209 Previous.clear(); 2210 } 2211 2212 // In C++, the previous declaration we find might be a tag type 2213 // (class or enum). In this case, the new declaration will hide the 2214 // tag type. Note that this does does not apply if we're declaring a 2215 // typedef (C++ [dcl.typedef]p4). 2216 if (Previous.isSingleTagDecl() && 2217 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2218 Previous.clear(); 2219 2220 bool Redeclaration = false; 2221 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2222 if (TemplateParamLists.size()) { 2223 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2224 return DeclPtrTy(); 2225 } 2226 2227 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2228 } else if (R->isFunctionType()) { 2229 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2230 move(TemplateParamLists), 2231 IsFunctionDefinition, Redeclaration); 2232 } else { 2233 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2234 move(TemplateParamLists), 2235 Redeclaration); 2236 } 2237 2238 if (New == 0) 2239 return DeclPtrTy(); 2240 2241 // If this has an identifier and is not an invalid redeclaration or 2242 // function template specialization, add it to the scope stack. 2243 if (Name && !(Redeclaration && New->isInvalidDecl())) 2244 PushOnScopeChains(New, S); 2245 2246 return DeclPtrTy::make(New); 2247} 2248 2249/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2250/// types into constant array types in certain situations which would otherwise 2251/// be errors (for GCC compatibility). 2252static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2253 ASTContext &Context, 2254 bool &SizeIsNegative) { 2255 // This method tries to turn a variable array into a constant 2256 // array even when the size isn't an ICE. This is necessary 2257 // for compatibility with code that depends on gcc's buggy 2258 // constant expression folding, like struct {char x[(int)(char*)2];} 2259 SizeIsNegative = false; 2260 2261 QualifierCollector Qs; 2262 const Type *Ty = Qs.strip(T); 2263 2264 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2265 QualType Pointee = PTy->getPointeeType(); 2266 QualType FixedType = 2267 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2268 if (FixedType.isNull()) return FixedType; 2269 FixedType = Context.getPointerType(FixedType); 2270 return Qs.apply(FixedType); 2271 } 2272 2273 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2274 if (!VLATy) 2275 return QualType(); 2276 // FIXME: We should probably handle this case 2277 if (VLATy->getElementType()->isVariablyModifiedType()) 2278 return QualType(); 2279 2280 Expr::EvalResult EvalResult; 2281 if (!VLATy->getSizeExpr() || 2282 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2283 !EvalResult.Val.isInt()) 2284 return QualType(); 2285 2286 llvm::APSInt &Res = EvalResult.Val.getInt(); 2287 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2288 // TODO: preserve the size expression in declarator info 2289 return Context.getConstantArrayType(VLATy->getElementType(), 2290 Res, ArrayType::Normal, 0); 2291 } 2292 2293 SizeIsNegative = true; 2294 return QualType(); 2295} 2296 2297/// \brief Register the given locally-scoped external C declaration so 2298/// that it can be found later for redeclarations 2299void 2300Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2301 const LookupResult &Previous, 2302 Scope *S) { 2303 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2304 "Decl is not a locally-scoped decl!"); 2305 // Note that we have a locally-scoped external with this name. 2306 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2307 2308 if (!Previous.isSingleResult()) 2309 return; 2310 2311 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2312 2313 // If there was a previous declaration of this variable, it may be 2314 // in our identifier chain. Update the identifier chain with the new 2315 // declaration. 2316 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2317 // The previous declaration was found on the identifer resolver 2318 // chain, so remove it from its scope. 2319 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2320 S = S->getParent(); 2321 2322 if (S) 2323 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2324 } 2325} 2326 2327/// \brief Diagnose function specifiers on a declaration of an identifier that 2328/// does not identify a function. 2329void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2330 // FIXME: We should probably indicate the identifier in question to avoid 2331 // confusion for constructs like "inline int a(), b;" 2332 if (D.getDeclSpec().isInlineSpecified()) 2333 Diag(D.getDeclSpec().getInlineSpecLoc(), 2334 diag::err_inline_non_function); 2335 2336 if (D.getDeclSpec().isVirtualSpecified()) 2337 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2338 diag::err_virtual_non_function); 2339 2340 if (D.getDeclSpec().isExplicitSpecified()) 2341 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2342 diag::err_explicit_non_function); 2343} 2344 2345NamedDecl* 2346Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2347 QualType R, TypeSourceInfo *TInfo, 2348 LookupResult &Previous, bool &Redeclaration) { 2349 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2350 if (D.getCXXScopeSpec().isSet()) { 2351 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2352 << D.getCXXScopeSpec().getRange(); 2353 D.setInvalidType(); 2354 // Pretend we didn't see the scope specifier. 2355 DC = 0; 2356 } 2357 2358 if (getLangOptions().CPlusPlus) { 2359 // Check that there are no default arguments (C++ only). 2360 CheckExtraCXXDefaultArguments(D); 2361 } 2362 2363 DiagnoseFunctionSpecifiers(D); 2364 2365 if (D.getDeclSpec().isThreadSpecified()) 2366 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2367 2368 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2369 if (!NewTD) return 0; 2370 2371 // Handle attributes prior to checking for duplicates in MergeVarDecl 2372 ProcessDeclAttributes(S, NewTD, D); 2373 2374 // Merge the decl with the existing one if appropriate. If the decl is 2375 // in an outer scope, it isn't the same thing. 2376 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2377 if (!Previous.empty()) { 2378 Redeclaration = true; 2379 MergeTypeDefDecl(NewTD, Previous); 2380 } 2381 2382 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2383 // then it shall have block scope. 2384 QualType T = NewTD->getUnderlyingType(); 2385 if (T->isVariablyModifiedType()) { 2386 CurFunctionNeedsScopeChecking = true; 2387 2388 if (S->getFnParent() == 0) { 2389 bool SizeIsNegative; 2390 QualType FixedTy = 2391 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2392 if (!FixedTy.isNull()) { 2393 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2394 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2395 } else { 2396 if (SizeIsNegative) 2397 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2398 else if (T->isVariableArrayType()) 2399 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2400 else 2401 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2402 NewTD->setInvalidDecl(); 2403 } 2404 } 2405 } 2406 2407 // If this is the C FILE type, notify the AST context. 2408 if (IdentifierInfo *II = NewTD->getIdentifier()) 2409 if (!NewTD->isInvalidDecl() && 2410 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2411 if (II->isStr("FILE")) 2412 Context.setFILEDecl(NewTD); 2413 else if (II->isStr("jmp_buf")) 2414 Context.setjmp_bufDecl(NewTD); 2415 else if (II->isStr("sigjmp_buf")) 2416 Context.setsigjmp_bufDecl(NewTD); 2417 } 2418 2419 return NewTD; 2420} 2421 2422/// \brief Determines whether the given declaration is an out-of-scope 2423/// previous declaration. 2424/// 2425/// This routine should be invoked when name lookup has found a 2426/// previous declaration (PrevDecl) that is not in the scope where a 2427/// new declaration by the same name is being introduced. If the new 2428/// declaration occurs in a local scope, previous declarations with 2429/// linkage may still be considered previous declarations (C99 2430/// 6.2.2p4-5, C++ [basic.link]p6). 2431/// 2432/// \param PrevDecl the previous declaration found by name 2433/// lookup 2434/// 2435/// \param DC the context in which the new declaration is being 2436/// declared. 2437/// 2438/// \returns true if PrevDecl is an out-of-scope previous declaration 2439/// for a new delcaration with the same name. 2440static bool 2441isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2442 ASTContext &Context) { 2443 if (!PrevDecl) 2444 return 0; 2445 2446 if (!PrevDecl->hasLinkage()) 2447 return false; 2448 2449 if (Context.getLangOptions().CPlusPlus) { 2450 // C++ [basic.link]p6: 2451 // If there is a visible declaration of an entity with linkage 2452 // having the same name and type, ignoring entities declared 2453 // outside the innermost enclosing namespace scope, the block 2454 // scope declaration declares that same entity and receives the 2455 // linkage of the previous declaration. 2456 DeclContext *OuterContext = DC->getLookupContext(); 2457 if (!OuterContext->isFunctionOrMethod()) 2458 // This rule only applies to block-scope declarations. 2459 return false; 2460 else { 2461 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2462 if (PrevOuterContext->isRecord()) 2463 // We found a member function: ignore it. 2464 return false; 2465 else { 2466 // Find the innermost enclosing namespace for the new and 2467 // previous declarations. 2468 while (!OuterContext->isFileContext()) 2469 OuterContext = OuterContext->getParent(); 2470 while (!PrevOuterContext->isFileContext()) 2471 PrevOuterContext = PrevOuterContext->getParent(); 2472 2473 // The previous declaration is in a different namespace, so it 2474 // isn't the same function. 2475 if (OuterContext->getPrimaryContext() != 2476 PrevOuterContext->getPrimaryContext()) 2477 return false; 2478 } 2479 } 2480 } 2481 2482 return true; 2483} 2484 2485NamedDecl* 2486Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2487 QualType R, TypeSourceInfo *TInfo, 2488 LookupResult &Previous, 2489 MultiTemplateParamsArg TemplateParamLists, 2490 bool &Redeclaration) { 2491 DeclarationName Name = GetNameForDeclarator(D); 2492 2493 // Check that there are no default arguments (C++ only). 2494 if (getLangOptions().CPlusPlus) 2495 CheckExtraCXXDefaultArguments(D); 2496 2497 VarDecl *NewVD; 2498 VarDecl::StorageClass SC; 2499 switch (D.getDeclSpec().getStorageClassSpec()) { 2500 default: assert(0 && "Unknown storage class!"); 2501 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2502 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2503 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2504 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2505 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2506 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2507 case DeclSpec::SCS_mutable: 2508 // mutable can only appear on non-static class members, so it's always 2509 // an error here 2510 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2511 D.setInvalidType(); 2512 SC = VarDecl::None; 2513 break; 2514 } 2515 2516 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2517 if (!II) { 2518 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2519 << Name.getAsString(); 2520 return 0; 2521 } 2522 2523 DiagnoseFunctionSpecifiers(D); 2524 2525 if (!DC->isRecord() && S->getFnParent() == 0) { 2526 // C99 6.9p2: The storage-class specifiers auto and register shall not 2527 // appear in the declaration specifiers in an external declaration. 2528 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2529 2530 // If this is a register variable with an asm label specified, then this 2531 // is a GNU extension. 2532 if (SC == VarDecl::Register && D.getAsmLabel()) 2533 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2534 else 2535 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2536 D.setInvalidType(); 2537 } 2538 } 2539 if (DC->isRecord() && !CurContext->isRecord()) { 2540 // This is an out-of-line definition of a static data member. 2541 if (SC == VarDecl::Static) { 2542 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2543 diag::err_static_out_of_line) 2544 << CodeModificationHint::CreateRemoval( 2545 D.getDeclSpec().getStorageClassSpecLoc()); 2546 } else if (SC == VarDecl::None) 2547 SC = VarDecl::Static; 2548 } 2549 if (SC == VarDecl::Static) { 2550 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2551 if (RD->isLocalClass()) 2552 Diag(D.getIdentifierLoc(), 2553 diag::err_static_data_member_not_allowed_in_local_class) 2554 << Name << RD->getDeclName(); 2555 } 2556 } 2557 2558 // Match up the template parameter lists with the scope specifier, then 2559 // determine whether we have a template or a template specialization. 2560 bool isExplicitSpecialization = false; 2561 if (TemplateParameterList *TemplateParams 2562 = MatchTemplateParametersToScopeSpecifier( 2563 D.getDeclSpec().getSourceRange().getBegin(), 2564 D.getCXXScopeSpec(), 2565 (TemplateParameterList**)TemplateParamLists.get(), 2566 TemplateParamLists.size(), 2567 isExplicitSpecialization)) { 2568 if (TemplateParams->size() > 0) { 2569 // There is no such thing as a variable template. 2570 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2571 << II 2572 << SourceRange(TemplateParams->getTemplateLoc(), 2573 TemplateParams->getRAngleLoc()); 2574 return 0; 2575 } else { 2576 // There is an extraneous 'template<>' for this variable. Complain 2577 // about it, but allow the declaration of the variable. 2578 Diag(TemplateParams->getTemplateLoc(), 2579 diag::err_template_variable_noparams) 2580 << II 2581 << SourceRange(TemplateParams->getTemplateLoc(), 2582 TemplateParams->getRAngleLoc()); 2583 2584 isExplicitSpecialization = true; 2585 } 2586 } 2587 2588 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2589 II, R, TInfo, SC); 2590 2591 if (D.isInvalidType()) 2592 NewVD->setInvalidDecl(); 2593 2594 if (D.getDeclSpec().isThreadSpecified()) { 2595 if (NewVD->hasLocalStorage()) 2596 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2597 else if (!Context.Target.isTLSSupported()) 2598 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2599 else 2600 NewVD->setThreadSpecified(true); 2601 } 2602 2603 // Set the lexical context. If the declarator has a C++ scope specifier, the 2604 // lexical context will be different from the semantic context. 2605 NewVD->setLexicalDeclContext(CurContext); 2606 2607 // Handle attributes prior to checking for duplicates in MergeVarDecl 2608 ProcessDeclAttributes(S, NewVD, D); 2609 2610 // Handle GNU asm-label extension (encoded as an attribute). 2611 if (Expr *E = (Expr*) D.getAsmLabel()) { 2612 // The parser guarantees this is a string. 2613 StringLiteral *SE = cast<StringLiteral>(E); 2614 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2615 } 2616 2617 // Don't consider existing declarations that are in a different 2618 // scope and are out-of-semantic-context declarations (if the new 2619 // declaration has linkage). 2620 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2621 2622 // Merge the decl with the existing one if appropriate. 2623 if (!Previous.empty()) { 2624 if (Previous.isSingleResult() && 2625 isa<FieldDecl>(Previous.getFoundDecl()) && 2626 D.getCXXScopeSpec().isSet()) { 2627 // The user tried to define a non-static data member 2628 // out-of-line (C++ [dcl.meaning]p1). 2629 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2630 << D.getCXXScopeSpec().getRange(); 2631 Previous.clear(); 2632 NewVD->setInvalidDecl(); 2633 } 2634 } else if (D.getCXXScopeSpec().isSet()) { 2635 // No previous declaration in the qualifying scope. 2636 Diag(D.getIdentifierLoc(), diag::err_no_member) 2637 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2638 << D.getCXXScopeSpec().getRange(); 2639 NewVD->setInvalidDecl(); 2640 } 2641 2642 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2643 2644 // This is an explicit specialization of a static data member. Check it. 2645 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2646 CheckMemberSpecialization(NewVD, Previous)) 2647 NewVD->setInvalidDecl(); 2648 2649 // attributes declared post-definition are currently ignored 2650 if (Previous.isSingleResult()) { 2651 const VarDecl *Def = 0; 2652 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2653 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2654 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2655 Diag(Def->getLocation(), diag::note_previous_definition); 2656 } 2657 } 2658 2659 // If this is a locally-scoped extern C variable, update the map of 2660 // such variables. 2661 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2662 !NewVD->isInvalidDecl()) 2663 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2664 2665 return NewVD; 2666} 2667 2668/// \brief Perform semantic checking on a newly-created variable 2669/// declaration. 2670/// 2671/// This routine performs all of the type-checking required for a 2672/// variable declaration once it has been built. It is used both to 2673/// check variables after they have been parsed and their declarators 2674/// have been translated into a declaration, and to check variables 2675/// that have been instantiated from a template. 2676/// 2677/// Sets NewVD->isInvalidDecl() if an error was encountered. 2678void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2679 LookupResult &Previous, 2680 bool &Redeclaration) { 2681 // If the decl is already known invalid, don't check it. 2682 if (NewVD->isInvalidDecl()) 2683 return; 2684 2685 QualType T = NewVD->getType(); 2686 2687 if (T->isObjCInterfaceType()) { 2688 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2689 return NewVD->setInvalidDecl(); 2690 } 2691 2692 // Emit an error if an address space was applied to decl with local storage. 2693 // This includes arrays of objects with address space qualifiers, but not 2694 // automatic variables that point to other address spaces. 2695 // ISO/IEC TR 18037 S5.1.2 2696 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2697 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2698 return NewVD->setInvalidDecl(); 2699 } 2700 2701 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2702 && !NewVD->hasAttr<BlocksAttr>()) 2703 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2704 2705 bool isVM = T->isVariablyModifiedType(); 2706 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2707 NewVD->hasAttr<BlocksAttr>()) 2708 CurFunctionNeedsScopeChecking = true; 2709 2710 if ((isVM && NewVD->hasLinkage()) || 2711 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2712 bool SizeIsNegative; 2713 QualType FixedTy = 2714 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2715 2716 if (FixedTy.isNull() && T->isVariableArrayType()) { 2717 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2718 // FIXME: This won't give the correct result for 2719 // int a[10][n]; 2720 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2721 2722 if (NewVD->isFileVarDecl()) 2723 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2724 << SizeRange; 2725 else if (NewVD->getStorageClass() == VarDecl::Static) 2726 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2727 << SizeRange; 2728 else 2729 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2730 << SizeRange; 2731 return NewVD->setInvalidDecl(); 2732 } 2733 2734 if (FixedTy.isNull()) { 2735 if (NewVD->isFileVarDecl()) 2736 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2737 else 2738 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2739 return NewVD->setInvalidDecl(); 2740 } 2741 2742 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2743 NewVD->setType(FixedTy); 2744 } 2745 2746 if (Previous.empty() && NewVD->isExternC()) { 2747 // Since we did not find anything by this name and we're declaring 2748 // an extern "C" variable, look for a non-visible extern "C" 2749 // declaration with the same name. 2750 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2751 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2752 if (Pos != LocallyScopedExternalDecls.end()) 2753 Previous.addDecl(Pos->second); 2754 } 2755 2756 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2757 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2758 << T; 2759 return NewVD->setInvalidDecl(); 2760 } 2761 2762 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2763 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2764 return NewVD->setInvalidDecl(); 2765 } 2766 2767 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2768 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2769 return NewVD->setInvalidDecl(); 2770 } 2771 2772 if (!Previous.empty()) { 2773 Redeclaration = true; 2774 MergeVarDecl(NewVD, Previous); 2775 } 2776} 2777 2778/// \brief Data used with FindOverriddenMethod 2779struct FindOverriddenMethodData { 2780 Sema *S; 2781 CXXMethodDecl *Method; 2782}; 2783 2784/// \brief Member lookup function that determines whether a given C++ 2785/// method overrides a method in a base class, to be used with 2786/// CXXRecordDecl::lookupInBases(). 2787static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2788 CXXBasePath &Path, 2789 void *UserData) { 2790 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2791 2792 FindOverriddenMethodData *Data 2793 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2794 2795 DeclarationName Name = Data->Method->getDeclName(); 2796 2797 // FIXME: Do we care about other names here too? 2798 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2799 // We really want to find the base class constructor here. 2800 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2801 CanQualType CT = Data->S->Context.getCanonicalType(T); 2802 2803 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2804 } 2805 2806 for (Path.Decls = BaseRecord->lookup(Name); 2807 Path.Decls.first != Path.Decls.second; 2808 ++Path.Decls.first) { 2809 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2810 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2811 return true; 2812 } 2813 } 2814 2815 return false; 2816} 2817 2818/// AddOverriddenMethods - See if a method overrides any in the base classes, 2819/// and if so, check that it's a valid override and remember it. 2820void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2821 // Look for virtual methods in base classes that this method might override. 2822 CXXBasePaths Paths; 2823 FindOverriddenMethodData Data; 2824 Data.Method = MD; 2825 Data.S = this; 2826 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2827 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2828 E = Paths.found_decls_end(); I != E; ++I) { 2829 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2830 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2831 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2832 !CheckOverridingFunctionAttributes(MD, OldMD)) 2833 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2834 } 2835 } 2836 } 2837} 2838 2839NamedDecl* 2840Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2841 QualType R, TypeSourceInfo *TInfo, 2842 LookupResult &Previous, 2843 MultiTemplateParamsArg TemplateParamLists, 2844 bool IsFunctionDefinition, bool &Redeclaration) { 2845 assert(R.getTypePtr()->isFunctionType()); 2846 2847 DeclarationName Name = GetNameForDeclarator(D); 2848 FunctionDecl::StorageClass SC = FunctionDecl::None; 2849 switch (D.getDeclSpec().getStorageClassSpec()) { 2850 default: assert(0 && "Unknown storage class!"); 2851 case DeclSpec::SCS_auto: 2852 case DeclSpec::SCS_register: 2853 case DeclSpec::SCS_mutable: 2854 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2855 diag::err_typecheck_sclass_func); 2856 D.setInvalidType(); 2857 break; 2858 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2859 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2860 case DeclSpec::SCS_static: { 2861 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2862 // C99 6.7.1p5: 2863 // The declaration of an identifier for a function that has 2864 // block scope shall have no explicit storage-class specifier 2865 // other than extern 2866 // See also (C++ [dcl.stc]p4). 2867 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2868 diag::err_static_block_func); 2869 SC = FunctionDecl::None; 2870 } else 2871 SC = FunctionDecl::Static; 2872 break; 2873 } 2874 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2875 } 2876 2877 if (D.getDeclSpec().isThreadSpecified()) 2878 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2879 2880 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2881 bool isInline = D.getDeclSpec().isInlineSpecified(); 2882 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2883 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2884 2885 // Check that the return type is not an abstract class type. 2886 // For record types, this is done by the AbstractClassUsageDiagnoser once 2887 // the class has been completely parsed. 2888 if (!DC->isRecord() && 2889 RequireNonAbstractType(D.getIdentifierLoc(), 2890 R->getAs<FunctionType>()->getResultType(), 2891 diag::err_abstract_type_in_decl, 2892 AbstractReturnType)) 2893 D.setInvalidType(); 2894 2895 // Do not allow returning a objc interface by-value. 2896 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2897 Diag(D.getIdentifierLoc(), 2898 diag::err_object_cannot_be_passed_returned_by_value) << 0 2899 << R->getAs<FunctionType>()->getResultType(); 2900 D.setInvalidType(); 2901 } 2902 2903 bool isVirtualOkay = false; 2904 FunctionDecl *NewFD; 2905 2906 if (isFriend) { 2907 // C++ [class.friend]p5 2908 // A function can be defined in a friend declaration of a 2909 // class . . . . Such a function is implicitly inline. 2910 isInline |= IsFunctionDefinition; 2911 } 2912 2913 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2914 // This is a C++ constructor declaration. 2915 assert(DC->isRecord() && 2916 "Constructors can only be declared in a member context"); 2917 2918 R = CheckConstructorDeclarator(D, R, SC); 2919 2920 // Create the new declaration 2921 NewFD = CXXConstructorDecl::Create(Context, 2922 cast<CXXRecordDecl>(DC), 2923 D.getIdentifierLoc(), Name, R, TInfo, 2924 isExplicit, isInline, 2925 /*isImplicitlyDeclared=*/false); 2926 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2927 // This is a C++ destructor declaration. 2928 if (DC->isRecord()) { 2929 R = CheckDestructorDeclarator(D, SC); 2930 2931 NewFD = CXXDestructorDecl::Create(Context, 2932 cast<CXXRecordDecl>(DC), 2933 D.getIdentifierLoc(), Name, R, 2934 isInline, 2935 /*isImplicitlyDeclared=*/false); 2936 2937 isVirtualOkay = true; 2938 } else { 2939 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2940 2941 // Create a FunctionDecl to satisfy the function definition parsing 2942 // code path. 2943 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2944 Name, R, TInfo, SC, isInline, 2945 /*hasPrototype=*/true); 2946 D.setInvalidType(); 2947 } 2948 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2949 if (!DC->isRecord()) { 2950 Diag(D.getIdentifierLoc(), 2951 diag::err_conv_function_not_member); 2952 return 0; 2953 } 2954 2955 CheckConversionDeclarator(D, R, SC); 2956 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2957 D.getIdentifierLoc(), Name, R, TInfo, 2958 isInline, isExplicit); 2959 2960 isVirtualOkay = true; 2961 } else if (DC->isRecord()) { 2962 // If the of the function is the same as the name of the record, then this 2963 // must be an invalid constructor that has a return type. 2964 // (The parser checks for a return type and makes the declarator a 2965 // constructor if it has no return type). 2966 // must have an invalid constructor that has a return type 2967 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2968 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2969 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2970 << SourceRange(D.getIdentifierLoc()); 2971 return 0; 2972 } 2973 2974 bool isStatic = SC == FunctionDecl::Static; 2975 2976 // [class.free]p1: 2977 // Any allocation function for a class T is a static member 2978 // (even if not explicitly declared static). 2979 if (Name.getCXXOverloadedOperator() == OO_New || 2980 Name.getCXXOverloadedOperator() == OO_Array_New) 2981 isStatic = true; 2982 2983 // [class.free]p6 Any deallocation function for a class X is a static member 2984 // (even if not explicitly declared static). 2985 if (Name.getCXXOverloadedOperator() == OO_Delete || 2986 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2987 isStatic = true; 2988 2989 // This is a C++ method declaration. 2990 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2991 D.getIdentifierLoc(), Name, R, TInfo, 2992 isStatic, isInline); 2993 2994 isVirtualOkay = !isStatic; 2995 } else { 2996 // Determine whether the function was written with a 2997 // prototype. This true when: 2998 // - we're in C++ (where every function has a prototype), 2999 // - there is a prototype in the declarator, or 3000 // - the type R of the function is some kind of typedef or other reference 3001 // to a type name (which eventually refers to a function type). 3002 bool HasPrototype = 3003 getLangOptions().CPlusPlus || 3004 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3005 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3006 3007 NewFD = FunctionDecl::Create(Context, DC, 3008 D.getIdentifierLoc(), 3009 Name, R, TInfo, SC, isInline, HasPrototype); 3010 } 3011 3012 if (D.isInvalidType()) 3013 NewFD->setInvalidDecl(); 3014 3015 // Set the lexical context. If the declarator has a C++ 3016 // scope specifier, or is the object of a friend declaration, the 3017 // lexical context will be different from the semantic context. 3018 NewFD->setLexicalDeclContext(CurContext); 3019 3020 // Match up the template parameter lists with the scope specifier, then 3021 // determine whether we have a template or a template specialization. 3022 FunctionTemplateDecl *FunctionTemplate = 0; 3023 bool isExplicitSpecialization = false; 3024 bool isFunctionTemplateSpecialization = false; 3025 if (TemplateParameterList *TemplateParams 3026 = MatchTemplateParametersToScopeSpecifier( 3027 D.getDeclSpec().getSourceRange().getBegin(), 3028 D.getCXXScopeSpec(), 3029 (TemplateParameterList**)TemplateParamLists.get(), 3030 TemplateParamLists.size(), 3031 isExplicitSpecialization)) { 3032 if (TemplateParams->size() > 0) { 3033 // This is a function template 3034 3035 // Check that we can declare a template here. 3036 if (CheckTemplateDeclScope(S, TemplateParams)) 3037 return 0; 3038 3039 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3040 NewFD->getLocation(), 3041 Name, TemplateParams, 3042 NewFD); 3043 FunctionTemplate->setLexicalDeclContext(CurContext); 3044 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3045 } else { 3046 // This is a function template specialization. 3047 isFunctionTemplateSpecialization = true; 3048 } 3049 3050 // FIXME: Free this memory properly. 3051 TemplateParamLists.release(); 3052 } 3053 3054 // C++ [dcl.fct.spec]p5: 3055 // The virtual specifier shall only be used in declarations of 3056 // nonstatic class member functions that appear within a 3057 // member-specification of a class declaration; see 10.3. 3058 // 3059 if (isVirtual && !NewFD->isInvalidDecl()) { 3060 if (!isVirtualOkay) { 3061 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3062 diag::err_virtual_non_function); 3063 } else if (!CurContext->isRecord()) { 3064 // 'virtual' was specified outside of the class. 3065 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3066 << CodeModificationHint::CreateRemoval( 3067 D.getDeclSpec().getVirtualSpecLoc()); 3068 } else { 3069 // Okay: Add virtual to the method. 3070 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3071 CurClass->setMethodAsVirtual(NewFD); 3072 } 3073 } 3074 3075 // Filter out previous declarations that don't match the scope. 3076 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3077 3078 if (isFriend) { 3079 // DC is the namespace in which the function is being declared. 3080 assert((DC->isFileContext() || !Previous.empty()) && 3081 "previously-undeclared friend function being created " 3082 "in a non-namespace context"); 3083 3084 if (FunctionTemplate) { 3085 FunctionTemplate->setObjectOfFriendDecl( 3086 /* PreviouslyDeclared= */ !Previous.empty()); 3087 FunctionTemplate->setAccess(AS_public); 3088 } 3089 else 3090 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 3091 3092 NewFD->setAccess(AS_public); 3093 } 3094 3095 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3096 !CurContext->isRecord()) { 3097 // C++ [class.static]p1: 3098 // A data or function member of a class may be declared static 3099 // in a class definition, in which case it is a static member of 3100 // the class. 3101 3102 // Complain about the 'static' specifier if it's on an out-of-line 3103 // member function definition. 3104 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3105 diag::err_static_out_of_line) 3106 << CodeModificationHint::CreateRemoval( 3107 D.getDeclSpec().getStorageClassSpecLoc()); 3108 } 3109 3110 // Handle GNU asm-label extension (encoded as an attribute). 3111 if (Expr *E = (Expr*) D.getAsmLabel()) { 3112 // The parser guarantees this is a string. 3113 StringLiteral *SE = cast<StringLiteral>(E); 3114 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 3115 } 3116 3117 // Copy the parameter declarations from the declarator D to the function 3118 // declaration NewFD, if they are available. First scavenge them into Params. 3119 llvm::SmallVector<ParmVarDecl*, 16> Params; 3120 if (D.getNumTypeObjects() > 0) { 3121 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3122 3123 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3124 // function that takes no arguments, not a function that takes a 3125 // single void argument. 3126 // We let through "const void" here because Sema::GetTypeForDeclarator 3127 // already checks for that case. 3128 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3129 FTI.ArgInfo[0].Param && 3130 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3131 // Empty arg list, don't push any params. 3132 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3133 3134 // In C++, the empty parameter-type-list must be spelled "void"; a 3135 // typedef of void is not permitted. 3136 if (getLangOptions().CPlusPlus && 3137 Param->getType().getUnqualifiedType() != Context.VoidTy) 3138 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3139 // FIXME: Leaks decl? 3140 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3141 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3142 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3143 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3144 Param->setDeclContext(NewFD); 3145 Params.push_back(Param); 3146 } 3147 } 3148 3149 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3150 // When we're declaring a function with a typedef, typeof, etc as in the 3151 // following example, we'll need to synthesize (unnamed) 3152 // parameters for use in the declaration. 3153 // 3154 // @code 3155 // typedef void fn(int); 3156 // fn f; 3157 // @endcode 3158 3159 // Synthesize a parameter for each argument type. 3160 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3161 AE = FT->arg_type_end(); AI != AE; ++AI) { 3162 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3163 SourceLocation(), 0, 3164 *AI, /*TInfo=*/0, 3165 VarDecl::None, 0); 3166 Param->setImplicit(); 3167 Params.push_back(Param); 3168 } 3169 } else { 3170 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3171 "Should not need args for typedef of non-prototype fn"); 3172 } 3173 // Finally, we know we have the right number of parameters, install them. 3174 NewFD->setParams(Context, Params.data(), Params.size()); 3175 3176 // If the declarator is a template-id, translate the parser's template 3177 // argument list into our AST format. 3178 bool HasExplicitTemplateArgs = false; 3179 TemplateArgumentListInfo TemplateArgs; 3180 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3181 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3182 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3183 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3184 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3185 TemplateId->getTemplateArgs(), 3186 TemplateId->NumArgs); 3187 translateTemplateArguments(TemplateArgsPtr, 3188 TemplateArgs); 3189 TemplateArgsPtr.release(); 3190 3191 HasExplicitTemplateArgs = true; 3192 3193 if (FunctionTemplate) { 3194 // FIXME: Diagnose function template with explicit template 3195 // arguments. 3196 HasExplicitTemplateArgs = false; 3197 } else if (!isFunctionTemplateSpecialization && 3198 !D.getDeclSpec().isFriendSpecified()) { 3199 // We have encountered something that the user meant to be a 3200 // specialization (because it has explicitly-specified template 3201 // arguments) but that was not introduced with a "template<>" (or had 3202 // too few of them). 3203 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3204 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3205 << CodeModificationHint::CreateInsertion( 3206 D.getDeclSpec().getSourceRange().getBegin(), 3207 "template<> "); 3208 isFunctionTemplateSpecialization = true; 3209 } 3210 } 3211 3212 if (isFunctionTemplateSpecialization) { 3213 if (CheckFunctionTemplateSpecialization(NewFD, 3214 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3215 Previous)) 3216 NewFD->setInvalidDecl(); 3217 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3218 CheckMemberSpecialization(NewFD, Previous)) 3219 NewFD->setInvalidDecl(); 3220 3221 // Perform semantic checking on the function declaration. 3222 bool OverloadableAttrRequired = false; // FIXME: HACK! 3223 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3224 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3225 3226 assert((NewFD->isInvalidDecl() || !Redeclaration || 3227 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3228 "previous declaration set still overloaded"); 3229 3230 // If we have a function template, check the template parameter 3231 // list. This will check and merge default template arguments. 3232 if (FunctionTemplate) { 3233 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3234 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3235 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3236 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3237 : TPC_FunctionTemplate); 3238 } 3239 3240 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3241 // An out-of-line member function declaration must also be a 3242 // definition (C++ [dcl.meaning]p1). 3243 // Note that this is not the case for explicit specializations of 3244 // function templates or member functions of class templates, per 3245 // C++ [temp.expl.spec]p2. 3246 if (!IsFunctionDefinition && !isFriend && 3247 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3248 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3249 << D.getCXXScopeSpec().getRange(); 3250 NewFD->setInvalidDecl(); 3251 } else if (!Redeclaration) { 3252 // The user tried to provide an out-of-line definition for a 3253 // function that is a member of a class or namespace, but there 3254 // was no such member function declared (C++ [class.mfct]p2, 3255 // C++ [namespace.memdef]p2). For example: 3256 // 3257 // class X { 3258 // void f() const; 3259 // }; 3260 // 3261 // void X::f() { } // ill-formed 3262 // 3263 // Complain about this problem, and attempt to suggest close 3264 // matches (e.g., those that differ only in cv-qualifiers and 3265 // whether the parameter types are references). 3266 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3267 << Name << DC << D.getCXXScopeSpec().getRange(); 3268 NewFD->setInvalidDecl(); 3269 3270 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3271 ForRedeclaration); 3272 LookupQualifiedName(Prev, DC); 3273 assert(!Prev.isAmbiguous() && 3274 "Cannot have an ambiguity in previous-declaration lookup"); 3275 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3276 Func != FuncEnd; ++Func) { 3277 if (isa<FunctionDecl>(*Func) && 3278 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3279 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3280 } 3281 } 3282 } 3283 3284 // Handle attributes. We need to have merged decls when handling attributes 3285 // (for example to check for conflicts, etc). 3286 // FIXME: This needs to happen before we merge declarations. Then, 3287 // let attribute merging cope with attribute conflicts. 3288 ProcessDeclAttributes(S, NewFD, D); 3289 3290 // attributes declared post-definition are currently ignored 3291 if (Redeclaration && Previous.isSingleResult()) { 3292 const FunctionDecl *Def; 3293 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3294 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3295 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3296 Diag(Def->getLocation(), diag::note_previous_definition); 3297 } 3298 } 3299 3300 AddKnownFunctionAttributes(NewFD); 3301 3302 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3303 // If a function name is overloadable in C, then every function 3304 // with that name must be marked "overloadable". 3305 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3306 << Redeclaration << NewFD; 3307 if (!Previous.empty()) 3308 Diag(Previous.getRepresentativeDecl()->getLocation(), 3309 diag::note_attribute_overloadable_prev_overload); 3310 NewFD->addAttr(::new (Context) OverloadableAttr()); 3311 } 3312 3313 // If this is a locally-scoped extern C function, update the 3314 // map of such names. 3315 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3316 && !NewFD->isInvalidDecl()) 3317 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3318 3319 // Set this FunctionDecl's range up to the right paren. 3320 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3321 3322 if (FunctionTemplate && NewFD->isInvalidDecl()) 3323 FunctionTemplate->setInvalidDecl(); 3324 3325 if (FunctionTemplate) 3326 return FunctionTemplate; 3327 3328 return NewFD; 3329} 3330 3331/// \brief Perform semantic checking of a new function declaration. 3332/// 3333/// Performs semantic analysis of the new function declaration 3334/// NewFD. This routine performs all semantic checking that does not 3335/// require the actual declarator involved in the declaration, and is 3336/// used both for the declaration of functions as they are parsed 3337/// (called via ActOnDeclarator) and for the declaration of functions 3338/// that have been instantiated via C++ template instantiation (called 3339/// via InstantiateDecl). 3340/// 3341/// \param IsExplicitSpecialiation whether this new function declaration is 3342/// an explicit specialization of the previous declaration. 3343/// 3344/// This sets NewFD->isInvalidDecl() to true if there was an error. 3345void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3346 LookupResult &Previous, 3347 bool IsExplicitSpecialization, 3348 bool &Redeclaration, 3349 bool &OverloadableAttrRequired) { 3350 // If NewFD is already known erroneous, don't do any of this checking. 3351 if (NewFD->isInvalidDecl()) 3352 return; 3353 3354 if (NewFD->getResultType()->isVariablyModifiedType()) { 3355 // Functions returning a variably modified type violate C99 6.7.5.2p2 3356 // because all functions have linkage. 3357 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3358 return NewFD->setInvalidDecl(); 3359 } 3360 3361 if (NewFD->isMain()) 3362 CheckMain(NewFD); 3363 3364 // Check for a previous declaration of this name. 3365 if (Previous.empty() && NewFD->isExternC()) { 3366 // Since we did not find anything by this name and we're declaring 3367 // an extern "C" function, look for a non-visible extern "C" 3368 // declaration with the same name. 3369 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3370 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3371 if (Pos != LocallyScopedExternalDecls.end()) 3372 Previous.addDecl(Pos->second); 3373 } 3374 3375 // Merge or overload the declaration with an existing declaration of 3376 // the same name, if appropriate. 3377 if (!Previous.empty()) { 3378 // Determine whether NewFD is an overload of PrevDecl or 3379 // a declaration that requires merging. If it's an overload, 3380 // there's no more work to do here; we'll just add the new 3381 // function to the scope. 3382 3383 NamedDecl *OldDecl = 0; 3384 if (!AllowOverloadingOfFunction(Previous, Context)) { 3385 Redeclaration = true; 3386 OldDecl = Previous.getFoundDecl(); 3387 } else { 3388 if (!getLangOptions().CPlusPlus) { 3389 OverloadableAttrRequired = true; 3390 3391 // Functions marked "overloadable" must have a prototype (that 3392 // we can't get through declaration merging). 3393 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3394 Diag(NewFD->getLocation(), 3395 diag::err_attribute_overloadable_no_prototype) 3396 << NewFD; 3397 Redeclaration = true; 3398 3399 // Turn this into a variadic function with no parameters. 3400 QualType R = Context.getFunctionType( 3401 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3402 0, 0, true, 0); 3403 NewFD->setType(R); 3404 return NewFD->setInvalidDecl(); 3405 } 3406 } 3407 3408 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3409 case Ovl_Match: 3410 Redeclaration = true; 3411 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3412 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3413 Redeclaration = false; 3414 } 3415 break; 3416 3417 case Ovl_NonFunction: 3418 Redeclaration = true; 3419 break; 3420 3421 case Ovl_Overload: 3422 Redeclaration = false; 3423 break; 3424 } 3425 } 3426 3427 if (Redeclaration) { 3428 // NewFD and OldDecl represent declarations that need to be 3429 // merged. 3430 if (MergeFunctionDecl(NewFD, OldDecl)) 3431 return NewFD->setInvalidDecl(); 3432 3433 Previous.clear(); 3434 Previous.addDecl(OldDecl); 3435 3436 if (FunctionTemplateDecl *OldTemplateDecl 3437 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3438 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3439 FunctionTemplateDecl *NewTemplateDecl 3440 = NewFD->getDescribedFunctionTemplate(); 3441 assert(NewTemplateDecl && "Template/non-template mismatch"); 3442 if (CXXMethodDecl *Method 3443 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3444 Method->setAccess(OldTemplateDecl->getAccess()); 3445 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3446 } 3447 3448 // If this is an explicit specialization of a member that is a function 3449 // template, mark it as a member specialization. 3450 if (IsExplicitSpecialization && 3451 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3452 NewTemplateDecl->setMemberSpecialization(); 3453 assert(OldTemplateDecl->isMemberSpecialization()); 3454 } 3455 } else { 3456 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3457 NewFD->setAccess(OldDecl->getAccess()); 3458 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3459 } 3460 } 3461 } 3462 3463 // Semantic checking for this function declaration (in isolation). 3464 if (getLangOptions().CPlusPlus) { 3465 // C++-specific checks. 3466 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3467 CheckConstructor(Constructor); 3468 } else if (CXXDestructorDecl *Destructor = 3469 dyn_cast<CXXDestructorDecl>(NewFD)) { 3470 CXXRecordDecl *Record = Destructor->getParent(); 3471 QualType ClassType = Context.getTypeDeclType(Record); 3472 3473 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3474 // type is dependent? Both gcc and edg can handle that. 3475 if (!ClassType->isDependentType()) { 3476 DeclarationName Name 3477 = Context.DeclarationNames.getCXXDestructorName( 3478 Context.getCanonicalType(ClassType)); 3479 if (NewFD->getDeclName() != Name) { 3480 Diag(NewFD->getLocation(), diag::err_destructor_name); 3481 return NewFD->setInvalidDecl(); 3482 } 3483 } 3484 3485 Record->setUserDeclaredDestructor(true); 3486 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3487 // user-defined destructor. 3488 Record->setPOD(false); 3489 3490 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3491 // declared destructor. 3492 // FIXME: C++0x: don't do this for "= default" destructors 3493 Record->setHasTrivialDestructor(false); 3494 } else if (CXXConversionDecl *Conversion 3495 = dyn_cast<CXXConversionDecl>(NewFD)) { 3496 ActOnConversionDeclarator(Conversion); 3497 } 3498 3499 // Find any virtual functions that this function overrides. 3500 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3501 if (!Method->isFunctionTemplateSpecialization() && 3502 !Method->getDescribedFunctionTemplate()) 3503 AddOverriddenMethods(Method->getParent(), Method); 3504 } 3505 3506 // Additional checks for the destructor; make sure we do this after we 3507 // figure out whether the destructor is virtual. 3508 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3509 if (!Destructor->getParent()->isDependentType()) 3510 CheckDestructor(Destructor); 3511 3512 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3513 if (NewFD->isOverloadedOperator() && 3514 CheckOverloadedOperatorDeclaration(NewFD)) 3515 return NewFD->setInvalidDecl(); 3516 3517 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3518 if (NewFD->getLiteralIdentifier() && 3519 CheckLiteralOperatorDeclaration(NewFD)) 3520 return NewFD->setInvalidDecl(); 3521 3522 // In C++, check default arguments now that we have merged decls. Unless 3523 // the lexical context is the class, because in this case this is done 3524 // during delayed parsing anyway. 3525 if (!CurContext->isRecord()) 3526 CheckCXXDefaultArguments(NewFD); 3527 } 3528} 3529 3530void Sema::CheckMain(FunctionDecl* FD) { 3531 // C++ [basic.start.main]p3: A program that declares main to be inline 3532 // or static is ill-formed. 3533 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3534 // shall not appear in a declaration of main. 3535 // static main is not an error under C99, but we should warn about it. 3536 bool isInline = FD->isInlineSpecified(); 3537 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3538 if (isInline || isStatic) { 3539 unsigned diagID = diag::warn_unusual_main_decl; 3540 if (isInline || getLangOptions().CPlusPlus) 3541 diagID = diag::err_unusual_main_decl; 3542 3543 int which = isStatic + (isInline << 1) - 1; 3544 Diag(FD->getLocation(), diagID) << which; 3545 } 3546 3547 QualType T = FD->getType(); 3548 assert(T->isFunctionType() && "function decl is not of function type"); 3549 const FunctionType* FT = T->getAs<FunctionType>(); 3550 3551 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3552 // TODO: add a replacement fixit to turn the return type into 'int'. 3553 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3554 FD->setInvalidDecl(true); 3555 } 3556 3557 // Treat protoless main() as nullary. 3558 if (isa<FunctionNoProtoType>(FT)) return; 3559 3560 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3561 unsigned nparams = FTP->getNumArgs(); 3562 assert(FD->getNumParams() == nparams); 3563 3564 bool HasExtraParameters = (nparams > 3); 3565 3566 // Darwin passes an undocumented fourth argument of type char**. If 3567 // other platforms start sprouting these, the logic below will start 3568 // getting shifty. 3569 if (nparams == 4 && 3570 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3571 HasExtraParameters = false; 3572 3573 if (HasExtraParameters) { 3574 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3575 FD->setInvalidDecl(true); 3576 nparams = 3; 3577 } 3578 3579 // FIXME: a lot of the following diagnostics would be improved 3580 // if we had some location information about types. 3581 3582 QualType CharPP = 3583 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3584 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3585 3586 for (unsigned i = 0; i < nparams; ++i) { 3587 QualType AT = FTP->getArgType(i); 3588 3589 bool mismatch = true; 3590 3591 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3592 mismatch = false; 3593 else if (Expected[i] == CharPP) { 3594 // As an extension, the following forms are okay: 3595 // char const ** 3596 // char const * const * 3597 // char * const * 3598 3599 QualifierCollector qs; 3600 const PointerType* PT; 3601 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3602 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3603 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3604 qs.removeConst(); 3605 mismatch = !qs.empty(); 3606 } 3607 } 3608 3609 if (mismatch) { 3610 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3611 // TODO: suggest replacing given type with expected type 3612 FD->setInvalidDecl(true); 3613 } 3614 } 3615 3616 if (nparams == 1 && !FD->isInvalidDecl()) { 3617 Diag(FD->getLocation(), diag::warn_main_one_arg); 3618 } 3619} 3620 3621bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3622 // FIXME: Need strict checking. In C89, we need to check for 3623 // any assignment, increment, decrement, function-calls, or 3624 // commas outside of a sizeof. In C99, it's the same list, 3625 // except that the aforementioned are allowed in unevaluated 3626 // expressions. Everything else falls under the 3627 // "may accept other forms of constant expressions" exception. 3628 // (We never end up here for C++, so the constant expression 3629 // rules there don't matter.) 3630 if (Init->isConstantInitializer(Context)) 3631 return false; 3632 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3633 << Init->getSourceRange(); 3634 return true; 3635} 3636 3637void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3638 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3639} 3640 3641/// AddInitializerToDecl - Adds the initializer Init to the 3642/// declaration dcl. If DirectInit is true, this is C++ direct 3643/// initialization rather than copy initialization. 3644void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3645 Decl *RealDecl = dcl.getAs<Decl>(); 3646 // If there is no declaration, there was an error parsing it. Just ignore 3647 // the initializer. 3648 if (RealDecl == 0) 3649 return; 3650 3651 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3652 // With declarators parsed the way they are, the parser cannot 3653 // distinguish between a normal initializer and a pure-specifier. 3654 // Thus this grotesque test. 3655 IntegerLiteral *IL; 3656 Expr *Init = static_cast<Expr *>(init.get()); 3657 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3658 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3659 CheckPureMethod(Method, Init->getSourceRange()); 3660 else { 3661 Diag(Method->getLocation(), diag::err_member_function_initialization) 3662 << Method->getDeclName() << Init->getSourceRange(); 3663 Method->setInvalidDecl(); 3664 } 3665 return; 3666 } 3667 3668 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3669 if (!VDecl) { 3670 if (getLangOptions().CPlusPlus && 3671 RealDecl->getLexicalDeclContext()->isRecord() && 3672 isa<NamedDecl>(RealDecl)) 3673 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3674 << cast<NamedDecl>(RealDecl)->getDeclName(); 3675 else 3676 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3677 RealDecl->setInvalidDecl(); 3678 return; 3679 } 3680 3681 // A definition must end up with a complete type, which means it must be 3682 // complete with the restriction that an array type might be completed by the 3683 // initializer; note that later code assumes this restriction. 3684 QualType BaseDeclType = VDecl->getType(); 3685 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3686 BaseDeclType = Array->getElementType(); 3687 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3688 diag::err_typecheck_decl_incomplete_type)) { 3689 RealDecl->setInvalidDecl(); 3690 return; 3691 } 3692 3693 // The variable can not have an abstract class type. 3694 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3695 diag::err_abstract_type_in_decl, 3696 AbstractVariableType)) 3697 VDecl->setInvalidDecl(); 3698 3699 const VarDecl *Def = 0; 3700 if (VDecl->getDefinition(Def)) { 3701 Diag(VDecl->getLocation(), diag::err_redefinition) 3702 << VDecl->getDeclName(); 3703 Diag(Def->getLocation(), diag::note_previous_definition); 3704 VDecl->setInvalidDecl(); 3705 return; 3706 } 3707 3708 // Take ownership of the expression, now that we're sure we have somewhere 3709 // to put it. 3710 Expr *Init = init.takeAs<Expr>(); 3711 assert(Init && "missing initializer"); 3712 3713 // Capture the variable that is being initialized and the style of 3714 // initialization. 3715 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3716 3717 // FIXME: Poor source location information. 3718 InitializationKind Kind 3719 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3720 Init->getLocStart(), 3721 Init->getLocEnd()) 3722 : InitializationKind::CreateCopy(VDecl->getLocation(), 3723 Init->getLocStart()); 3724 3725 // Get the decls type and save a reference for later, since 3726 // CheckInitializerTypes may change it. 3727 QualType DclT = VDecl->getType(), SavT = DclT; 3728 if (VDecl->isBlockVarDecl()) { 3729 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3730 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3731 VDecl->setInvalidDecl(); 3732 } else if (!VDecl->isInvalidDecl()) { 3733 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3734 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3735 MultiExprArg(*this, (void**)&Init, 1), 3736 &DclT); 3737 if (Result.isInvalid()) { 3738 VDecl->setInvalidDecl(); 3739 return; 3740 } 3741 3742 Init = Result.takeAs<Expr>(); 3743 3744 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3745 // Don't check invalid declarations to avoid emitting useless diagnostics. 3746 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3747 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3748 CheckForConstantInitializer(Init, DclT); 3749 } 3750 } 3751 } else if (VDecl->isStaticDataMember() && 3752 VDecl->getLexicalDeclContext()->isRecord()) { 3753 // This is an in-class initialization for a static data member, e.g., 3754 // 3755 // struct S { 3756 // static const int value = 17; 3757 // }; 3758 3759 // Attach the initializer 3760 VDecl->setInit(Context, Init); 3761 3762 // C++ [class.mem]p4: 3763 // A member-declarator can contain a constant-initializer only 3764 // if it declares a static member (9.4) of const integral or 3765 // const enumeration type, see 9.4.2. 3766 QualType T = VDecl->getType(); 3767 if (!T->isDependentType() && 3768 (!Context.getCanonicalType(T).isConstQualified() || 3769 !T->isIntegralType())) { 3770 Diag(VDecl->getLocation(), diag::err_member_initialization) 3771 << VDecl->getDeclName() << Init->getSourceRange(); 3772 VDecl->setInvalidDecl(); 3773 } else { 3774 // C++ [class.static.data]p4: 3775 // If a static data member is of const integral or const 3776 // enumeration type, its declaration in the class definition 3777 // can specify a constant-initializer which shall be an 3778 // integral constant expression (5.19). 3779 if (!Init->isTypeDependent() && 3780 !Init->getType()->isIntegralType()) { 3781 // We have a non-dependent, non-integral or enumeration type. 3782 Diag(Init->getSourceRange().getBegin(), 3783 diag::err_in_class_initializer_non_integral_type) 3784 << Init->getType() << Init->getSourceRange(); 3785 VDecl->setInvalidDecl(); 3786 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3787 // Check whether the expression is a constant expression. 3788 llvm::APSInt Value; 3789 SourceLocation Loc; 3790 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3791 Diag(Loc, diag::err_in_class_initializer_non_constant) 3792 << Init->getSourceRange(); 3793 VDecl->setInvalidDecl(); 3794 } else if (!VDecl->getType()->isDependentType()) 3795 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3796 } 3797 } 3798 } else if (VDecl->isFileVarDecl()) { 3799 if (VDecl->getStorageClass() == VarDecl::Extern) 3800 Diag(VDecl->getLocation(), diag::warn_extern_init); 3801 if (!VDecl->isInvalidDecl()) { 3802 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3803 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3804 MultiExprArg(*this, (void**)&Init, 1), 3805 &DclT); 3806 if (Result.isInvalid()) { 3807 VDecl->setInvalidDecl(); 3808 return; 3809 } 3810 3811 Init = Result.takeAs<Expr>(); 3812 } 3813 3814 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3815 // Don't check invalid declarations to avoid emitting useless diagnostics. 3816 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3817 // C99 6.7.8p4. All file scoped initializers need to be constant. 3818 CheckForConstantInitializer(Init, DclT); 3819 } 3820 } 3821 // If the type changed, it means we had an incomplete type that was 3822 // completed by the initializer. For example: 3823 // int ary[] = { 1, 3, 5 }; 3824 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3825 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3826 VDecl->setType(DclT); 3827 Init->setType(DclT); 3828 } 3829 3830 Init = MaybeCreateCXXExprWithTemporaries(Init); 3831 // Attach the initializer to the decl. 3832 VDecl->setInit(Context, Init); 3833 3834 // If the previous declaration of VDecl was a tentative definition, 3835 // remove it from the set of tentative definitions. 3836 if (VDecl->getPreviousDeclaration() && 3837 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3838 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3839 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3840 } 3841 3842 if (getLangOptions().CPlusPlus) { 3843 // Make sure we mark the destructor as used if necessary. 3844 QualType InitType = VDecl->getType(); 3845 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3846 InitType = Context.getBaseElementType(Array); 3847 if (InitType->isRecordType()) 3848 FinalizeVarWithDestructor(VDecl, InitType); 3849 } 3850 3851 return; 3852} 3853 3854void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3855 bool TypeContainsUndeducedAuto) { 3856 Decl *RealDecl = dcl.getAs<Decl>(); 3857 3858 // If there is no declaration, there was an error parsing it. Just ignore it. 3859 if (RealDecl == 0) 3860 return; 3861 3862 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3863 QualType Type = Var->getType(); 3864 3865 // Record tentative definitions. 3866 if (Var->isTentativeDefinition(Context)) { 3867 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3868 InsertPair = 3869 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3870 3871 // Keep the latest definition in the map. If we see 'int i; int i;' we 3872 // want the second one in the map. 3873 InsertPair.first->second = Var; 3874 3875 // However, for the list, we don't care about the order, just make sure 3876 // that there are no dupes for a given declaration name. 3877 if (InsertPair.second) 3878 TentativeDefinitionList.push_back(Var->getDeclName()); 3879 } 3880 3881 // C++ [dcl.init.ref]p3: 3882 // The initializer can be omitted for a reference only in a 3883 // parameter declaration (8.3.5), in the declaration of a 3884 // function return type, in the declaration of a class member 3885 // within its class declaration (9.2), and where the extern 3886 // specifier is explicitly used. 3887 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3888 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3889 << Var->getDeclName() 3890 << SourceRange(Var->getLocation(), Var->getLocation()); 3891 Var->setInvalidDecl(); 3892 return; 3893 } 3894 3895 // C++0x [dcl.spec.auto]p3 3896 if (TypeContainsUndeducedAuto) { 3897 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3898 << Var->getDeclName() << Type; 3899 Var->setInvalidDecl(); 3900 return; 3901 } 3902 3903 // An array without size is an incomplete type, and there are no special 3904 // rules in C++ to make such a definition acceptable. 3905 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3906 !Var->hasExternalStorage()) { 3907 Diag(Var->getLocation(), 3908 diag::err_typecheck_incomplete_array_needs_initializer); 3909 Var->setInvalidDecl(); 3910 return; 3911 } 3912 3913 // C++ [temp.expl.spec]p15: 3914 // An explicit specialization of a static data member of a template is a 3915 // definition if the declaration includes an initializer; otherwise, it 3916 // is a declaration. 3917 if (Var->isStaticDataMember() && 3918 Var->getInstantiatedFromStaticDataMember() && 3919 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3920 return; 3921 3922 // C++ [dcl.init]p9: 3923 // If no initializer is specified for an object, and the object 3924 // is of (possibly cv-qualified) non-POD class type (or array 3925 // thereof), the object shall be default-initialized; if the 3926 // object is of const-qualified type, the underlying class type 3927 // shall have a user-declared default constructor. 3928 // 3929 // FIXME: Diagnose the "user-declared default constructor" bit. 3930 if (getLangOptions().CPlusPlus) { 3931 QualType InitType = Type; 3932 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3933 InitType = Context.getBaseElementType(Array); 3934 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3935 InitType->isRecordType() && !InitType->isDependentType()) { 3936 if (!RequireCompleteType(Var->getLocation(), InitType, 3937 diag::err_invalid_incomplete_type_use)) { 3938 InitializedEntity Entity 3939 = InitializedEntity::InitializeVariable(Var); 3940 InitializationKind Kind 3941 = InitializationKind::CreateDefault(Var->getLocation()); 3942 3943 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 3944 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 3945 MultiExprArg(*this, 0, 0)); 3946 if (Init.isInvalid()) 3947 Var->setInvalidDecl(); 3948 else { 3949 Var->setInit(Context, 3950 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 3951 FinalizeVarWithDestructor(Var, InitType); 3952 } 3953 } else { 3954 Var->setInvalidDecl(); 3955 } 3956 } 3957 3958 // The variable can not have an abstract class type. 3959 if (RequireNonAbstractType(Var->getLocation(), Type, 3960 diag::err_abstract_type_in_decl, 3961 AbstractVariableType)) 3962 Var->setInvalidDecl(); 3963 } 3964 3965#if 0 3966 // FIXME: Temporarily disabled because we are not properly parsing 3967 // linkage specifications on declarations, e.g., 3968 // 3969 // extern "C" const CGPoint CGPointerZero; 3970 // 3971 // C++ [dcl.init]p9: 3972 // 3973 // If no initializer is specified for an object, and the 3974 // object is of (possibly cv-qualified) non-POD class type (or 3975 // array thereof), the object shall be default-initialized; if 3976 // the object is of const-qualified type, the underlying class 3977 // type shall have a user-declared default 3978 // constructor. Otherwise, if no initializer is specified for 3979 // an object, the object and its subobjects, if any, have an 3980 // indeterminate initial value; if the object or any of its 3981 // subobjects are of const-qualified type, the program is 3982 // ill-formed. 3983 // 3984 // This isn't technically an error in C, so we don't diagnose it. 3985 // 3986 // FIXME: Actually perform the POD/user-defined default 3987 // constructor check. 3988 if (getLangOptions().CPlusPlus && 3989 Context.getCanonicalType(Type).isConstQualified() && 3990 !Var->hasExternalStorage()) 3991 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3992 << Var->getName() 3993 << SourceRange(Var->getLocation(), Var->getLocation()); 3994#endif 3995 } 3996} 3997 3998Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3999 DeclPtrTy *Group, 4000 unsigned NumDecls) { 4001 llvm::SmallVector<Decl*, 8> Decls; 4002 4003 if (DS.isTypeSpecOwned()) 4004 Decls.push_back((Decl*)DS.getTypeRep()); 4005 4006 for (unsigned i = 0; i != NumDecls; ++i) 4007 if (Decl *D = Group[i].getAs<Decl>()) 4008 Decls.push_back(D); 4009 4010 // Perform semantic analysis that depends on having fully processed both 4011 // the declarator and initializer. 4012 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 4013 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 4014 if (!IDecl) 4015 continue; 4016 QualType T = IDecl->getType(); 4017 4018 // Block scope. C99 6.7p7: If an identifier for an object is declared with 4019 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 4020 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 4021 if (T->isDependentType()) { 4022 // If T is dependent, we should not require a complete type. 4023 // (RequireCompleteType shouldn't be called with dependent types.) 4024 // But we still can at least check if we've got an array of unspecified 4025 // size without an initializer. 4026 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 4027 !IDecl->getInit()) { 4028 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 4029 << T; 4030 IDecl->setInvalidDecl(); 4031 } 4032 } else if (!IDecl->isInvalidDecl()) { 4033 // If T is an incomplete array type with an initializer list that is 4034 // dependent on something, its size has not been fixed. We could attempt 4035 // to fix the size for such arrays, but we would still have to check 4036 // here for initializers containing a C++0x vararg expansion, e.g. 4037 // template <typename... Args> void f(Args... args) { 4038 // int vals[] = { args }; 4039 // } 4040 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 4041 Expr *Init = IDecl->getInit(); 4042 if (IAT && Init && 4043 (Init->isTypeDependent() || Init->isValueDependent())) { 4044 // Check that the member type of the array is complete, at least. 4045 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 4046 diag::err_typecheck_decl_incomplete_type)) 4047 IDecl->setInvalidDecl(); 4048 } else if (RequireCompleteType(IDecl->getLocation(), T, 4049 diag::err_typecheck_decl_incomplete_type)) 4050 IDecl->setInvalidDecl(); 4051 } 4052 } 4053 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4054 // object that has file scope without an initializer, and without a 4055 // storage-class specifier or with the storage-class specifier "static", 4056 // constitutes a tentative definition. Note: A tentative definition with 4057 // external linkage is valid (C99 6.2.2p5). 4058 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 4059 if (const IncompleteArrayType *ArrayT 4060 = Context.getAsIncompleteArrayType(T)) { 4061 if (RequireCompleteType(IDecl->getLocation(), 4062 ArrayT->getElementType(), 4063 diag::err_illegal_decl_array_incomplete_type)) 4064 IDecl->setInvalidDecl(); 4065 } else if (IDecl->getStorageClass() == VarDecl::Static) { 4066 // C99 6.9.2p3: If the declaration of an identifier for an object is 4067 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4068 // declared type shall not be an incomplete type. 4069 // NOTE: code such as the following 4070 // static struct s; 4071 // struct s { int a; }; 4072 // is accepted by gcc. Hence here we issue a warning instead of 4073 // an error and we do not invalidate the static declaration. 4074 // NOTE: to avoid multiple warnings, only check the first declaration. 4075 if (IDecl->getPreviousDeclaration() == 0) 4076 RequireCompleteType(IDecl->getLocation(), T, 4077 diag::ext_typecheck_decl_incomplete_type); 4078 } 4079 } 4080 } 4081 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4082 Decls.data(), Decls.size())); 4083} 4084 4085 4086/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4087/// to introduce parameters into function prototype scope. 4088Sema::DeclPtrTy 4089Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4090 const DeclSpec &DS = D.getDeclSpec(); 4091 4092 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4093 VarDecl::StorageClass StorageClass = VarDecl::None; 4094 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4095 StorageClass = VarDecl::Register; 4096 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4097 Diag(DS.getStorageClassSpecLoc(), 4098 diag::err_invalid_storage_class_in_func_decl); 4099 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4100 } 4101 4102 if (D.getDeclSpec().isThreadSpecified()) 4103 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4104 4105 DiagnoseFunctionSpecifiers(D); 4106 4107 // Check that there are no default arguments inside the type of this 4108 // parameter (C++ only). 4109 if (getLangOptions().CPlusPlus) 4110 CheckExtraCXXDefaultArguments(D); 4111 4112 TypeSourceInfo *TInfo = 0; 4113 TagDecl *OwnedDecl = 0; 4114 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4115 4116 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4117 // C++ [dcl.fct]p6: 4118 // Types shall not be defined in return or parameter types. 4119 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4120 << Context.getTypeDeclType(OwnedDecl); 4121 } 4122 4123 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 4124 // Can this happen for params? We already checked that they don't conflict 4125 // among each other. Here they can only shadow globals, which is ok. 4126 IdentifierInfo *II = D.getIdentifier(); 4127 if (II) { 4128 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 4129 if (PrevDecl->isTemplateParameter()) { 4130 // Maybe we will complain about the shadowed template parameter. 4131 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4132 // Just pretend that we didn't see the previous declaration. 4133 PrevDecl = 0; 4134 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4135 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4136 4137 // Recover by removing the name 4138 II = 0; 4139 D.SetIdentifier(0, D.getIdentifierLoc()); 4140 } 4141 } 4142 } 4143 4144 // Parameters can not be abstract class types. 4145 // For record types, this is done by the AbstractClassUsageDiagnoser once 4146 // the class has been completely parsed. 4147 if (!CurContext->isRecord() && 4148 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4149 diag::err_abstract_type_in_decl, 4150 AbstractParamType)) 4151 D.setInvalidType(true); 4152 4153 QualType T = adjustParameterType(parmDeclType); 4154 4155 ParmVarDecl *New 4156 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 4157 T, TInfo, StorageClass, 0); 4158 4159 if (D.isInvalidType()) 4160 New->setInvalidDecl(); 4161 4162 // Parameter declarators cannot be interface types. All ObjC objects are 4163 // passed by reference. 4164 if (T->isObjCInterfaceType()) { 4165 Diag(D.getIdentifierLoc(), 4166 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4167 New->setInvalidDecl(); 4168 } 4169 4170 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4171 if (D.getCXXScopeSpec().isSet()) { 4172 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4173 << D.getCXXScopeSpec().getRange(); 4174 New->setInvalidDecl(); 4175 } 4176 4177 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4178 // duration shall not be qualified by an address-space qualifier." 4179 // Since all parameters have automatic store duration, they can not have 4180 // an address space. 4181 if (T.getAddressSpace() != 0) { 4182 Diag(D.getIdentifierLoc(), 4183 diag::err_arg_with_address_space); 4184 New->setInvalidDecl(); 4185 } 4186 4187 4188 // Add the parameter declaration into this scope. 4189 S->AddDecl(DeclPtrTy::make(New)); 4190 if (II) 4191 IdResolver.AddDecl(New); 4192 4193 ProcessDeclAttributes(S, New, D); 4194 4195 if (New->hasAttr<BlocksAttr>()) { 4196 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4197 } 4198 return DeclPtrTy::make(New); 4199} 4200 4201void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4202 SourceLocation LocAfterDecls) { 4203 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4204 "Not a function declarator!"); 4205 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4206 4207 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4208 // for a K&R function. 4209 if (!FTI.hasPrototype) { 4210 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4211 --i; 4212 if (FTI.ArgInfo[i].Param == 0) { 4213 llvm::SmallString<256> Code; 4214 llvm::raw_svector_ostream(Code) << " int " 4215 << FTI.ArgInfo[i].Ident->getName() 4216 << ";\n"; 4217 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4218 << FTI.ArgInfo[i].Ident 4219 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4220 4221 // Implicitly declare the argument as type 'int' for lack of a better 4222 // type. 4223 DeclSpec DS; 4224 const char* PrevSpec; // unused 4225 unsigned DiagID; // unused 4226 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4227 PrevSpec, DiagID); 4228 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4229 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4230 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4231 } 4232 } 4233 } 4234} 4235 4236Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4237 Declarator &D) { 4238 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4239 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4240 "Not a function declarator!"); 4241 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4242 4243 if (FTI.hasPrototype) { 4244 // FIXME: Diagnose arguments without names in C. 4245 } 4246 4247 Scope *ParentScope = FnBodyScope->getParent(); 4248 4249 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4250 MultiTemplateParamsArg(*this), 4251 /*IsFunctionDefinition=*/true); 4252 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4253} 4254 4255static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4256 // Don't warn about invalid declarations. 4257 if (FD->isInvalidDecl()) 4258 return false; 4259 4260 // Or declarations that aren't global. 4261 if (!FD->isGlobal()) 4262 return false; 4263 4264 // Don't warn about C++ member functions. 4265 if (isa<CXXMethodDecl>(FD)) 4266 return false; 4267 4268 // Don't warn about 'main'. 4269 if (FD->isMain()) 4270 return false; 4271 4272 // Don't warn about inline functions. 4273 if (FD->isInlineSpecified()) 4274 return false; 4275 4276 // Don't warn about function templates. 4277 if (FD->getDescribedFunctionTemplate()) 4278 return false; 4279 4280 // Don't warn about function template specializations. 4281 if (FD->isFunctionTemplateSpecialization()) 4282 return false; 4283 4284 bool MissingPrototype = true; 4285 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4286 Prev; Prev = Prev->getPreviousDeclaration()) { 4287 // Ignore any declarations that occur in function or method 4288 // scope, because they aren't visible from the header. 4289 if (Prev->getDeclContext()->isFunctionOrMethod()) 4290 continue; 4291 4292 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4293 break; 4294 } 4295 4296 return MissingPrototype; 4297} 4298 4299Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4300 // Clear the last template instantiation error context. 4301 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4302 4303 if (!D) 4304 return D; 4305 FunctionDecl *FD = 0; 4306 4307 if (FunctionTemplateDecl *FunTmpl 4308 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4309 FD = FunTmpl->getTemplatedDecl(); 4310 else 4311 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4312 4313 CurFunctionNeedsScopeChecking = false; 4314 4315 // See if this is a redefinition. 4316 const FunctionDecl *Definition; 4317 if (FD->getBody(Definition)) { 4318 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4319 Diag(Definition->getLocation(), diag::note_previous_definition); 4320 } 4321 4322 // Builtin functions cannot be defined. 4323 if (unsigned BuiltinID = FD->getBuiltinID()) { 4324 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4325 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4326 FD->setInvalidDecl(); 4327 } 4328 } 4329 4330 // The return type of a function definition must be complete 4331 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4332 QualType ResultType = FD->getResultType(); 4333 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4334 !FD->isInvalidDecl() && 4335 RequireCompleteType(FD->getLocation(), ResultType, 4336 diag::err_func_def_incomplete_result)) 4337 FD->setInvalidDecl(); 4338 4339 // GNU warning -Wmissing-prototypes: 4340 // Warn if a global function is defined without a previous 4341 // prototype declaration. This warning is issued even if the 4342 // definition itself provides a prototype. The aim is to detect 4343 // global functions that fail to be declared in header files. 4344 if (ShouldWarnAboutMissingPrototype(FD)) 4345 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4346 4347 if (FnBodyScope) 4348 PushDeclContext(FnBodyScope, FD); 4349 4350 // Check the validity of our function parameters 4351 CheckParmsForFunctionDef(FD); 4352 4353 // Introduce our parameters into the function scope 4354 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4355 ParmVarDecl *Param = FD->getParamDecl(p); 4356 Param->setOwningFunction(FD); 4357 4358 // If this has an identifier, add it to the scope stack. 4359 if (Param->getIdentifier() && FnBodyScope) 4360 PushOnScopeChains(Param, FnBodyScope); 4361 } 4362 4363 // Checking attributes of current function definition 4364 // dllimport attribute. 4365 if (FD->getAttr<DLLImportAttr>() && 4366 (!FD->getAttr<DLLExportAttr>())) { 4367 // dllimport attribute cannot be applied to definition. 4368 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4369 Diag(FD->getLocation(), 4370 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4371 << "dllimport"; 4372 FD->setInvalidDecl(); 4373 return DeclPtrTy::make(FD); 4374 } else { 4375 // If a symbol previously declared dllimport is later defined, the 4376 // attribute is ignored in subsequent references, and a warning is 4377 // emitted. 4378 Diag(FD->getLocation(), 4379 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4380 << FD->getNameAsCString() << "dllimport"; 4381 } 4382 } 4383 return DeclPtrTy::make(FD); 4384} 4385 4386Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4387 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4388} 4389 4390Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4391 bool IsInstantiation) { 4392 Decl *dcl = D.getAs<Decl>(); 4393 Stmt *Body = BodyArg.takeAs<Stmt>(); 4394 4395 AnalysisContext AC(dcl); 4396 FunctionDecl *FD = 0; 4397 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4398 if (FunTmpl) 4399 FD = FunTmpl->getTemplatedDecl(); 4400 else 4401 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4402 4403 if (FD) { 4404 FD->setBody(Body); 4405 if (FD->isMain()) 4406 // C and C++ allow for main to automagically return 0. 4407 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4408 FD->setHasImplicitReturnZero(true); 4409 else 4410 CheckFallThroughForFunctionDef(FD, Body, AC); 4411 4412 if (!FD->isInvalidDecl()) 4413 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4414 4415 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4416 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4417 4418 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4419 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4420 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4421 MD->setBody(Body); 4422 CheckFallThroughForFunctionDef(MD, Body, AC); 4423 MD->setEndLoc(Body->getLocEnd()); 4424 4425 if (!MD->isInvalidDecl()) 4426 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4427 } else { 4428 Body->Destroy(Context); 4429 return DeclPtrTy(); 4430 } 4431 if (!IsInstantiation) 4432 PopDeclContext(); 4433 4434 // Verify and clean out per-function state. 4435 4436 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4437 4438 // Check goto/label use. 4439 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4440 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4441 LabelStmt *L = I->second; 4442 4443 // Verify that we have no forward references left. If so, there was a goto 4444 // or address of a label taken, but no definition of it. Label fwd 4445 // definitions are indicated with a null substmt. 4446 if (L->getSubStmt() != 0) 4447 continue; 4448 4449 // Emit error. 4450 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4451 4452 // At this point, we have gotos that use the bogus label. Stitch it into 4453 // the function body so that they aren't leaked and that the AST is well 4454 // formed. 4455 if (Body == 0) { 4456 // The whole function wasn't parsed correctly, just delete this. 4457 L->Destroy(Context); 4458 continue; 4459 } 4460 4461 // Otherwise, the body is valid: we want to stitch the label decl into the 4462 // function somewhere so that it is properly owned and so that the goto 4463 // has a valid target. Do this by creating a new compound stmt with the 4464 // label in it. 4465 4466 // Give the label a sub-statement. 4467 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4468 4469 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4470 cast<CXXTryStmt>(Body)->getTryBlock() : 4471 cast<CompoundStmt>(Body); 4472 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4473 Elements.push_back(L); 4474 Compound->setStmts(Context, &Elements[0], Elements.size()); 4475 } 4476 FunctionLabelMap.clear(); 4477 4478 if (!Body) return D; 4479 4480 CheckUnreachable(AC); 4481 4482 // Verify that that gotos and switch cases don't jump into scopes illegally. 4483 if (CurFunctionNeedsScopeChecking) 4484 DiagnoseInvalidJumps(Body); 4485 4486 // C++ constructors that have function-try-blocks can't have return 4487 // statements in the handlers of that block. (C++ [except.handle]p14) 4488 // Verify this. 4489 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4490 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4491 4492 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4493 MarkBaseAndMemberDestructorsReferenced(Destructor); 4494 4495 // If any errors have occurred, clear out any temporaries that may have 4496 // been leftover. This ensures that these temporaries won't be picked up for 4497 // deletion in some later function. 4498 if (PP.getDiagnostics().hasErrorOccurred()) 4499 ExprTemporaries.clear(); 4500 4501 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4502 return D; 4503} 4504 4505/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4506/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4507NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4508 IdentifierInfo &II, Scope *S) { 4509 // Before we produce a declaration for an implicitly defined 4510 // function, see whether there was a locally-scoped declaration of 4511 // this name as a function or variable. If so, use that 4512 // (non-visible) declaration, and complain about it. 4513 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4514 = LocallyScopedExternalDecls.find(&II); 4515 if (Pos != LocallyScopedExternalDecls.end()) { 4516 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4517 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4518 return Pos->second; 4519 } 4520 4521 // Extension in C99. Legal in C90, but warn about it. 4522 if (II.getName().startswith("__builtin_")) 4523 Diag(Loc, diag::warn_builtin_unknown) << &II; 4524 else if (getLangOptions().C99) 4525 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4526 else 4527 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4528 4529 // Set a Declarator for the implicit definition: int foo(); 4530 const char *Dummy; 4531 DeclSpec DS; 4532 unsigned DiagID; 4533 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4534 Error = Error; // Silence warning. 4535 assert(!Error && "Error setting up implicit decl!"); 4536 Declarator D(DS, Declarator::BlockContext); 4537 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4538 0, 0, false, SourceLocation(), 4539 false, 0,0,0, Loc, Loc, D), 4540 SourceLocation()); 4541 D.SetIdentifier(&II, Loc); 4542 4543 // Insert this function into translation-unit scope. 4544 4545 DeclContext *PrevDC = CurContext; 4546 CurContext = Context.getTranslationUnitDecl(); 4547 4548 FunctionDecl *FD = 4549 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4550 FD->setImplicit(); 4551 4552 CurContext = PrevDC; 4553 4554 AddKnownFunctionAttributes(FD); 4555 4556 return FD; 4557} 4558 4559/// \brief Adds any function attributes that we know a priori based on 4560/// the declaration of this function. 4561/// 4562/// These attributes can apply both to implicitly-declared builtins 4563/// (like __builtin___printf_chk) or to library-declared functions 4564/// like NSLog or printf. 4565void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4566 if (FD->isInvalidDecl()) 4567 return; 4568 4569 // If this is a built-in function, map its builtin attributes to 4570 // actual attributes. 4571 if (unsigned BuiltinID = FD->getBuiltinID()) { 4572 // Handle printf-formatting attributes. 4573 unsigned FormatIdx; 4574 bool HasVAListArg; 4575 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4576 if (!FD->getAttr<FormatAttr>()) 4577 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4578 HasVAListArg ? 0 : FormatIdx + 2)); 4579 } 4580 4581 // Mark const if we don't care about errno and that is the only 4582 // thing preventing the function from being const. This allows 4583 // IRgen to use LLVM intrinsics for such functions. 4584 if (!getLangOptions().MathErrno && 4585 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4586 if (!FD->getAttr<ConstAttr>()) 4587 FD->addAttr(::new (Context) ConstAttr()); 4588 } 4589 4590 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4591 FD->addAttr(::new (Context) NoReturnAttr()); 4592 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4593 FD->addAttr(::new (Context) NoThrowAttr()); 4594 if (Context.BuiltinInfo.isConst(BuiltinID)) 4595 FD->addAttr(::new (Context) ConstAttr()); 4596 } 4597 4598 IdentifierInfo *Name = FD->getIdentifier(); 4599 if (!Name) 4600 return; 4601 if ((!getLangOptions().CPlusPlus && 4602 FD->getDeclContext()->isTranslationUnit()) || 4603 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4604 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4605 LinkageSpecDecl::lang_c)) { 4606 // Okay: this could be a libc/libm/Objective-C function we know 4607 // about. 4608 } else 4609 return; 4610 4611 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4612 // FIXME: NSLog and NSLogv should be target specific 4613 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4614 // FIXME: We known better than our headers. 4615 const_cast<FormatAttr *>(Format)->setType("printf"); 4616 } else 4617 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4618 Name->isStr("NSLogv") ? 0 : 2)); 4619 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4620 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4621 // target-specific builtins, perhaps? 4622 if (!FD->getAttr<FormatAttr>()) 4623 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4624 Name->isStr("vasprintf") ? 0 : 3)); 4625 } 4626} 4627 4628TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4629 TypeSourceInfo *TInfo) { 4630 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4631 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4632 4633 if (!TInfo) { 4634 assert(D.isInvalidType() && "no declarator info for valid type"); 4635 TInfo = Context.getTrivialTypeSourceInfo(T); 4636 } 4637 4638 // Scope manipulation handled by caller. 4639 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4640 D.getIdentifierLoc(), 4641 D.getIdentifier(), 4642 TInfo); 4643 4644 if (const TagType *TT = T->getAs<TagType>()) { 4645 TagDecl *TD = TT->getDecl(); 4646 4647 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4648 // keep track of the TypedefDecl. 4649 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4650 TD->setTypedefForAnonDecl(NewTD); 4651 } 4652 4653 if (D.isInvalidType()) 4654 NewTD->setInvalidDecl(); 4655 return NewTD; 4656} 4657 4658 4659/// \brief Determine whether a tag with a given kind is acceptable 4660/// as a redeclaration of the given tag declaration. 4661/// 4662/// \returns true if the new tag kind is acceptable, false otherwise. 4663bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4664 TagDecl::TagKind NewTag, 4665 SourceLocation NewTagLoc, 4666 const IdentifierInfo &Name) { 4667 // C++ [dcl.type.elab]p3: 4668 // The class-key or enum keyword present in the 4669 // elaborated-type-specifier shall agree in kind with the 4670 // declaration to which the name in theelaborated-type-specifier 4671 // refers. This rule also applies to the form of 4672 // elaborated-type-specifier that declares a class-name or 4673 // friend class since it can be construed as referring to the 4674 // definition of the class. Thus, in any 4675 // elaborated-type-specifier, the enum keyword shall be used to 4676 // refer to an enumeration (7.2), the union class-keyshall be 4677 // used to refer to a union (clause 9), and either the class or 4678 // struct class-key shall be used to refer to a class (clause 9) 4679 // declared using the class or struct class-key. 4680 TagDecl::TagKind OldTag = Previous->getTagKind(); 4681 if (OldTag == NewTag) 4682 return true; 4683 4684 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4685 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4686 // Warn about the struct/class tag mismatch. 4687 bool isTemplate = false; 4688 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4689 isTemplate = Record->getDescribedClassTemplate(); 4690 4691 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4692 << (NewTag == TagDecl::TK_class) 4693 << isTemplate << &Name 4694 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4695 OldTag == TagDecl::TK_class? "class" : "struct"); 4696 Diag(Previous->getLocation(), diag::note_previous_use); 4697 return true; 4698 } 4699 return false; 4700} 4701 4702/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4703/// former case, Name will be non-null. In the later case, Name will be null. 4704/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4705/// reference/declaration/definition of a tag. 4706Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4707 SourceLocation KWLoc, const CXXScopeSpec &SS, 4708 IdentifierInfo *Name, SourceLocation NameLoc, 4709 AttributeList *Attr, AccessSpecifier AS, 4710 MultiTemplateParamsArg TemplateParameterLists, 4711 bool &OwnedDecl, bool &IsDependent) { 4712 // If this is not a definition, it must have a name. 4713 assert((Name != 0 || TUK == TUK_Definition) && 4714 "Nameless record must be a definition!"); 4715 4716 OwnedDecl = false; 4717 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4718 4719 // FIXME: Check explicit specializations more carefully. 4720 bool isExplicitSpecialization = false; 4721 if (TUK != TUK_Reference) { 4722 if (TemplateParameterList *TemplateParams 4723 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4724 (TemplateParameterList**)TemplateParameterLists.get(), 4725 TemplateParameterLists.size(), 4726 isExplicitSpecialization)) { 4727 if (TemplateParams->size() > 0) { 4728 // This is a declaration or definition of a class template (which may 4729 // be a member of another template). 4730 OwnedDecl = false; 4731 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4732 SS, Name, NameLoc, Attr, 4733 TemplateParams, 4734 AS); 4735 TemplateParameterLists.release(); 4736 return Result.get(); 4737 } else { 4738 // The "template<>" header is extraneous. 4739 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4740 << ElaboratedType::getNameForTagKind(Kind) << Name; 4741 isExplicitSpecialization = true; 4742 } 4743 } 4744 4745 TemplateParameterLists.release(); 4746 } 4747 4748 DeclContext *SearchDC = CurContext; 4749 DeclContext *DC = CurContext; 4750 bool isStdBadAlloc = false; 4751 bool Invalid = false; 4752 4753 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4754 : NotForRedeclaration); 4755 4756 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4757 4758 if (Name && SS.isNotEmpty()) { 4759 // We have a nested-name tag ('struct foo::bar'). 4760 4761 // Check for invalid 'foo::'. 4762 if (SS.isInvalid()) { 4763 Name = 0; 4764 goto CreateNewDecl; 4765 } 4766 4767 // If this is a friend or a reference to a class in a dependent 4768 // context, don't try to make a decl for it. 4769 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4770 DC = computeDeclContext(SS, false); 4771 if (!DC) { 4772 IsDependent = true; 4773 return DeclPtrTy(); 4774 } 4775 } 4776 4777 if (RequireCompleteDeclContext(SS)) 4778 return DeclPtrTy::make((Decl *)0); 4779 4780 DC = computeDeclContext(SS, true); 4781 SearchDC = DC; 4782 // Look-up name inside 'foo::'. 4783 LookupQualifiedName(Previous, DC); 4784 4785 if (Previous.isAmbiguous()) 4786 return DeclPtrTy(); 4787 4788 if (Previous.empty()) { 4789 // Name lookup did not find anything. However, if the 4790 // nested-name-specifier refers to the current instantiation, 4791 // and that current instantiation has any dependent base 4792 // classes, we might find something at instantiation time: treat 4793 // this as a dependent elaborated-type-specifier. 4794 if (isCurrentInstantiationWithDependentBases(SS)) { 4795 IsDependent = true; 4796 return DeclPtrTy(); 4797 } 4798 4799 // A tag 'foo::bar' must already exist. 4800 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4801 Name = 0; 4802 Invalid = true; 4803 goto CreateNewDecl; 4804 } 4805 } else if (Name) { 4806 // If this is a named struct, check to see if there was a previous forward 4807 // declaration or definition. 4808 // FIXME: We're looking into outer scopes here, even when we 4809 // shouldn't be. Doing so can result in ambiguities that we 4810 // shouldn't be diagnosing. 4811 LookupName(Previous, S); 4812 4813 // Note: there used to be some attempt at recovery here. 4814 if (Previous.isAmbiguous()) 4815 return DeclPtrTy(); 4816 4817 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4818 // FIXME: This makes sure that we ignore the contexts associated 4819 // with C structs, unions, and enums when looking for a matching 4820 // tag declaration or definition. See the similar lookup tweak 4821 // in Sema::LookupName; is there a better way to deal with this? 4822 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4823 SearchDC = SearchDC->getParent(); 4824 } 4825 } 4826 4827 if (Previous.isSingleResult() && 4828 Previous.getFoundDecl()->isTemplateParameter()) { 4829 // Maybe we will complain about the shadowed template parameter. 4830 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4831 // Just pretend that we didn't see the previous declaration. 4832 Previous.clear(); 4833 } 4834 4835 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4836 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4837 // This is a declaration of or a reference to "std::bad_alloc". 4838 isStdBadAlloc = true; 4839 4840 if (Previous.empty() && StdBadAlloc) { 4841 // std::bad_alloc has been implicitly declared (but made invisible to 4842 // name lookup). Fill in this implicit declaration as the previous 4843 // declaration, so that the declarations get chained appropriately. 4844 Previous.addDecl(StdBadAlloc); 4845 } 4846 } 4847 4848 if (!Previous.empty()) { 4849 assert(Previous.isSingleResult()); 4850 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4851 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4852 // If this is a use of a previous tag, or if the tag is already declared 4853 // in the same scope (so that the definition/declaration completes or 4854 // rementions the tag), reuse the decl. 4855 if (TUK == TUK_Reference || TUK == TUK_Friend || 4856 isDeclInScope(PrevDecl, SearchDC, S)) { 4857 // Make sure that this wasn't declared as an enum and now used as a 4858 // struct or something similar. 4859 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4860 bool SafeToContinue 4861 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4862 Kind != TagDecl::TK_enum); 4863 if (SafeToContinue) 4864 Diag(KWLoc, diag::err_use_with_wrong_tag) 4865 << Name 4866 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4867 PrevTagDecl->getKindName()); 4868 else 4869 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4870 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4871 4872 if (SafeToContinue) 4873 Kind = PrevTagDecl->getTagKind(); 4874 else { 4875 // Recover by making this an anonymous redefinition. 4876 Name = 0; 4877 Previous.clear(); 4878 Invalid = true; 4879 } 4880 } 4881 4882 if (!Invalid) { 4883 // If this is a use, just return the declaration we found. 4884 4885 // FIXME: In the future, return a variant or some other clue 4886 // for the consumer of this Decl to know it doesn't own it. 4887 // For our current ASTs this shouldn't be a problem, but will 4888 // need to be changed with DeclGroups. 4889 if (TUK == TUK_Reference || TUK == TUK_Friend) 4890 return DeclPtrTy::make(PrevTagDecl); 4891 4892 // Diagnose attempts to redefine a tag. 4893 if (TUK == TUK_Definition) { 4894 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4895 // If we're defining a specialization and the previous definition 4896 // is from an implicit instantiation, don't emit an error 4897 // here; we'll catch this in the general case below. 4898 if (!isExplicitSpecialization || 4899 !isa<CXXRecordDecl>(Def) || 4900 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4901 == TSK_ExplicitSpecialization) { 4902 Diag(NameLoc, diag::err_redefinition) << Name; 4903 Diag(Def->getLocation(), diag::note_previous_definition); 4904 // If this is a redefinition, recover by making this 4905 // struct be anonymous, which will make any later 4906 // references get the previous definition. 4907 Name = 0; 4908 Previous.clear(); 4909 Invalid = true; 4910 } 4911 } else { 4912 // If the type is currently being defined, complain 4913 // about a nested redefinition. 4914 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4915 if (Tag->isBeingDefined()) { 4916 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4917 Diag(PrevTagDecl->getLocation(), 4918 diag::note_previous_definition); 4919 Name = 0; 4920 Previous.clear(); 4921 Invalid = true; 4922 } 4923 } 4924 4925 // Okay, this is definition of a previously declared or referenced 4926 // tag PrevDecl. We're going to create a new Decl for it. 4927 } 4928 } 4929 // If we get here we have (another) forward declaration or we 4930 // have a definition. Just create a new decl. 4931 4932 } else { 4933 // If we get here, this is a definition of a new tag type in a nested 4934 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4935 // new decl/type. We set PrevDecl to NULL so that the entities 4936 // have distinct types. 4937 Previous.clear(); 4938 } 4939 // If we get here, we're going to create a new Decl. If PrevDecl 4940 // is non-NULL, it's a definition of the tag declared by 4941 // PrevDecl. If it's NULL, we have a new definition. 4942 } else { 4943 // PrevDecl is a namespace, template, or anything else 4944 // that lives in the IDNS_Tag identifier namespace. 4945 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4946 // The tag name clashes with a namespace name, issue an error and 4947 // recover by making this tag be anonymous. 4948 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4949 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4950 Name = 0; 4951 Previous.clear(); 4952 Invalid = true; 4953 } else { 4954 // The existing declaration isn't relevant to us; we're in a 4955 // new scope, so clear out the previous declaration. 4956 Previous.clear(); 4957 } 4958 } 4959 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4960 // C++ [basic.scope.pdecl]p5: 4961 // -- for an elaborated-type-specifier of the form 4962 // 4963 // class-key identifier 4964 // 4965 // if the elaborated-type-specifier is used in the 4966 // decl-specifier-seq or parameter-declaration-clause of a 4967 // function defined in namespace scope, the identifier is 4968 // declared as a class-name in the namespace that contains 4969 // the declaration; otherwise, except as a friend 4970 // declaration, the identifier is declared in the smallest 4971 // non-class, non-function-prototype scope that contains the 4972 // declaration. 4973 // 4974 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4975 // C structs and unions. 4976 // 4977 // It is an error in C++ to declare (rather than define) an enum 4978 // type, including via an elaborated type specifier. We'll 4979 // diagnose that later; for now, declare the enum in the same 4980 // scope as we would have picked for any other tag type. 4981 // 4982 // GNU C also supports this behavior as part of its incomplete 4983 // enum types extension, while GNU C++ does not. 4984 // 4985 // Find the context where we'll be declaring the tag. 4986 // FIXME: We would like to maintain the current DeclContext as the 4987 // lexical context, 4988 while (SearchDC->isRecord()) 4989 SearchDC = SearchDC->getParent(); 4990 4991 // Find the scope where we'll be declaring the tag. 4992 while (S->isClassScope() || 4993 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4994 ((S->getFlags() & Scope::DeclScope) == 0) || 4995 (S->getEntity() && 4996 ((DeclContext *)S->getEntity())->isTransparentContext())) 4997 S = S->getParent(); 4998 4999 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 5000 // C++ [namespace.memdef]p3: 5001 // If a friend declaration in a non-local class first declares a 5002 // class or function, the friend class or function is a member of 5003 // the innermost enclosing namespace. 5004 while (!SearchDC->isFileContext()) 5005 SearchDC = SearchDC->getParent(); 5006 5007 // The entity of a decl scope is a DeclContext; see PushDeclContext. 5008 while (S->getEntity() != SearchDC) 5009 S = S->getParent(); 5010 } 5011 5012CreateNewDecl: 5013 5014 TagDecl *PrevDecl = 0; 5015 if (Previous.isSingleResult()) 5016 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5017 5018 // If there is an identifier, use the location of the identifier as the 5019 // location of the decl, otherwise use the location of the struct/union 5020 // keyword. 5021 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5022 5023 // Otherwise, create a new declaration. If there is a previous 5024 // declaration of the same entity, the two will be linked via 5025 // PrevDecl. 5026 TagDecl *New; 5027 5028 if (Kind == TagDecl::TK_enum) { 5029 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5030 // enum X { A, B, C } D; D should chain to X. 5031 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5032 cast_or_null<EnumDecl>(PrevDecl)); 5033 // If this is an undefined enum, warn. 5034 if (TUK != TUK_Definition && !Invalid) { 5035 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5036 : diag::ext_forward_ref_enum; 5037 Diag(Loc, DK); 5038 } 5039 } else { 5040 // struct/union/class 5041 5042 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5043 // struct X { int A; } D; D should chain to X. 5044 if (getLangOptions().CPlusPlus) { 5045 // FIXME: Look for a way to use RecordDecl for simple structs. 5046 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5047 cast_or_null<CXXRecordDecl>(PrevDecl)); 5048 5049 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5050 StdBadAlloc = cast<CXXRecordDecl>(New); 5051 } else 5052 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5053 cast_or_null<RecordDecl>(PrevDecl)); 5054 } 5055 5056 if (Kind != TagDecl::TK_enum) { 5057 // Handle #pragma pack: if the #pragma pack stack has non-default 5058 // alignment, make up a packed attribute for this decl. These 5059 // attributes are checked when the ASTContext lays out the 5060 // structure. 5061 // 5062 // It is important for implementing the correct semantics that this 5063 // happen here (in act on tag decl). The #pragma pack stack is 5064 // maintained as a result of parser callbacks which can occur at 5065 // many points during the parsing of a struct declaration (because 5066 // the #pragma tokens are effectively skipped over during the 5067 // parsing of the struct). 5068 if (unsigned Alignment = getPragmaPackAlignment()) 5069 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5070 } 5071 5072 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5073 // C++ [dcl.typedef]p3: 5074 // [...] Similarly, in a given scope, a class or enumeration 5075 // shall not be declared with the same name as a typedef-name 5076 // that is declared in that scope and refers to a type other 5077 // than the class or enumeration itself. 5078 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5079 ForRedeclaration); 5080 LookupName(Lookup, S); 5081 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5082 NamedDecl *PrevTypedefNamed = PrevTypedef; 5083 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5084 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5085 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5086 Diag(Loc, diag::err_tag_definition_of_typedef) 5087 << Context.getTypeDeclType(New) 5088 << PrevTypedef->getUnderlyingType(); 5089 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5090 Invalid = true; 5091 } 5092 } 5093 5094 // If this is a specialization of a member class (of a class template), 5095 // check the specialization. 5096 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5097 Invalid = true; 5098 5099 if (Invalid) 5100 New->setInvalidDecl(); 5101 5102 if (Attr) 5103 ProcessDeclAttributeList(S, New, Attr); 5104 5105 // If we're declaring or defining a tag in function prototype scope 5106 // in C, note that this type can only be used within the function. 5107 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5108 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5109 5110 // Set the lexical context. If the tag has a C++ scope specifier, the 5111 // lexical context will be different from the semantic context. 5112 New->setLexicalDeclContext(CurContext); 5113 5114 // Mark this as a friend decl if applicable. 5115 if (TUK == TUK_Friend) 5116 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5117 5118 // Set the access specifier. 5119 if (!Invalid && TUK != TUK_Friend) 5120 SetMemberAccessSpecifier(New, PrevDecl, AS); 5121 5122 if (TUK == TUK_Definition) 5123 New->startDefinition(); 5124 5125 // If this has an identifier, add it to the scope stack. 5126 if (TUK == TUK_Friend) { 5127 // We might be replacing an existing declaration in the lookup tables; 5128 // if so, borrow its access specifier. 5129 if (PrevDecl) 5130 New->setAccess(PrevDecl->getAccess()); 5131 5132 // Friend tag decls are visible in fairly strange ways. 5133 if (!CurContext->isDependentContext()) { 5134 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5135 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5136 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5137 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5138 } 5139 } else if (Name) { 5140 S = getNonFieldDeclScope(S); 5141 PushOnScopeChains(New, S); 5142 } else { 5143 CurContext->addDecl(New); 5144 } 5145 5146 // If this is the C FILE type, notify the AST context. 5147 if (IdentifierInfo *II = New->getIdentifier()) 5148 if (!New->isInvalidDecl() && 5149 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5150 II->isStr("FILE")) 5151 Context.setFILEDecl(New); 5152 5153 OwnedDecl = true; 5154 return DeclPtrTy::make(New); 5155} 5156 5157void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5158 AdjustDeclIfTemplate(TagD); 5159 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5160 5161 // Enter the tag context. 5162 PushDeclContext(S, Tag); 5163} 5164 5165void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5166 SourceLocation LBraceLoc) { 5167 AdjustDeclIfTemplate(TagD); 5168 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5169 5170 FieldCollector->StartClass(); 5171 5172 if (!Record->getIdentifier()) 5173 return; 5174 5175 // C++ [class]p2: 5176 // [...] The class-name is also inserted into the scope of the 5177 // class itself; this is known as the injected-class-name. For 5178 // purposes of access checking, the injected-class-name is treated 5179 // as if it were a public member name. 5180 CXXRecordDecl *InjectedClassName 5181 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5182 CurContext, Record->getLocation(), 5183 Record->getIdentifier(), 5184 Record->getTagKeywordLoc(), 5185 Record); 5186 InjectedClassName->setImplicit(); 5187 InjectedClassName->setAccess(AS_public); 5188 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5189 InjectedClassName->setDescribedClassTemplate(Template); 5190 PushOnScopeChains(InjectedClassName, S); 5191 assert(InjectedClassName->isInjectedClassName() && 5192 "Broken injected-class-name"); 5193} 5194 5195// Traverses the class and any nested classes, making a note of any 5196// dynamic classes that have no key function so that we can mark all of 5197// their virtual member functions as "used" at the end of the translation 5198// unit. This ensures that all functions needed by the vtable will get 5199// instantiated/synthesized. 5200static void 5201RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5202 SourceLocation Loc) { 5203 // We don't look at dependent or undefined classes. 5204 if (Record->isDependentContext() || !Record->isDefinition()) 5205 return; 5206 5207 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 5208 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 5209 5210 for (DeclContext::decl_iterator D = Record->decls_begin(), 5211 DEnd = Record->decls_end(); 5212 D != DEnd; ++D) { 5213 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5214 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5215 } 5216} 5217 5218void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5219 SourceLocation RBraceLoc) { 5220 AdjustDeclIfTemplate(TagD); 5221 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5222 Tag->setRBraceLoc(RBraceLoc); 5223 5224 if (isa<CXXRecordDecl>(Tag)) 5225 FieldCollector->FinishClass(); 5226 5227 // Exit this scope of this tag's definition. 5228 PopDeclContext(); 5229 5230 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 5231 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5232 RBraceLoc); 5233 5234 // Notify the consumer that we've defined a tag. 5235 Consumer.HandleTagDeclDefinition(Tag); 5236} 5237 5238// Note that FieldName may be null for anonymous bitfields. 5239bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5240 QualType FieldTy, const Expr *BitWidth, 5241 bool *ZeroWidth) { 5242 // Default to true; that shouldn't confuse checks for emptiness 5243 if (ZeroWidth) 5244 *ZeroWidth = true; 5245 5246 // C99 6.7.2.1p4 - verify the field type. 5247 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5248 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5249 // Handle incomplete types with specific error. 5250 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5251 return true; 5252 if (FieldName) 5253 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5254 << FieldName << FieldTy << BitWidth->getSourceRange(); 5255 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5256 << FieldTy << BitWidth->getSourceRange(); 5257 } 5258 5259 // If the bit-width is type- or value-dependent, don't try to check 5260 // it now. 5261 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5262 return false; 5263 5264 llvm::APSInt Value; 5265 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5266 return true; 5267 5268 if (Value != 0 && ZeroWidth) 5269 *ZeroWidth = false; 5270 5271 // Zero-width bitfield is ok for anonymous field. 5272 if (Value == 0 && FieldName) 5273 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5274 5275 if (Value.isSigned() && Value.isNegative()) { 5276 if (FieldName) 5277 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5278 << FieldName << Value.toString(10); 5279 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5280 << Value.toString(10); 5281 } 5282 5283 if (!FieldTy->isDependentType()) { 5284 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5285 if (Value.getZExtValue() > TypeSize) { 5286 if (FieldName) 5287 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5288 << FieldName << (unsigned)TypeSize; 5289 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5290 << (unsigned)TypeSize; 5291 } 5292 } 5293 5294 return false; 5295} 5296 5297/// ActOnField - Each field of a struct/union/class is passed into this in order 5298/// to create a FieldDecl object for it. 5299Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5300 SourceLocation DeclStart, 5301 Declarator &D, ExprTy *BitfieldWidth) { 5302 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5303 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5304 AS_public); 5305 return DeclPtrTy::make(Res); 5306} 5307 5308/// HandleField - Analyze a field of a C struct or a C++ data member. 5309/// 5310FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5311 SourceLocation DeclStart, 5312 Declarator &D, Expr *BitWidth, 5313 AccessSpecifier AS) { 5314 IdentifierInfo *II = D.getIdentifier(); 5315 SourceLocation Loc = DeclStart; 5316 if (II) Loc = D.getIdentifierLoc(); 5317 5318 TypeSourceInfo *TInfo = 0; 5319 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5320 if (getLangOptions().CPlusPlus) 5321 CheckExtraCXXDefaultArguments(D); 5322 5323 DiagnoseFunctionSpecifiers(D); 5324 5325 if (D.getDeclSpec().isThreadSpecified()) 5326 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5327 5328 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5329 ForRedeclaration); 5330 5331 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5332 // Maybe we will complain about the shadowed template parameter. 5333 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5334 // Just pretend that we didn't see the previous declaration. 5335 PrevDecl = 0; 5336 } 5337 5338 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5339 PrevDecl = 0; 5340 5341 bool Mutable 5342 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5343 SourceLocation TSSL = D.getSourceRange().getBegin(); 5344 FieldDecl *NewFD 5345 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5346 AS, PrevDecl, &D); 5347 if (NewFD->isInvalidDecl() && PrevDecl) { 5348 // Don't introduce NewFD into scope; there's already something 5349 // with the same name in the same scope. 5350 } else if (II) { 5351 PushOnScopeChains(NewFD, S); 5352 } else 5353 Record->addDecl(NewFD); 5354 5355 return NewFD; 5356} 5357 5358/// \brief Build a new FieldDecl and check its well-formedness. 5359/// 5360/// This routine builds a new FieldDecl given the fields name, type, 5361/// record, etc. \p PrevDecl should refer to any previous declaration 5362/// with the same name and in the same scope as the field to be 5363/// created. 5364/// 5365/// \returns a new FieldDecl. 5366/// 5367/// \todo The Declarator argument is a hack. It will be removed once 5368FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5369 TypeSourceInfo *TInfo, 5370 RecordDecl *Record, SourceLocation Loc, 5371 bool Mutable, Expr *BitWidth, 5372 SourceLocation TSSL, 5373 AccessSpecifier AS, NamedDecl *PrevDecl, 5374 Declarator *D) { 5375 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5376 bool InvalidDecl = false; 5377 if (D) InvalidDecl = D->isInvalidType(); 5378 5379 // If we receive a broken type, recover by assuming 'int' and 5380 // marking this declaration as invalid. 5381 if (T.isNull()) { 5382 InvalidDecl = true; 5383 T = Context.IntTy; 5384 } 5385 5386 QualType EltTy = Context.getBaseElementType(T); 5387 if (!EltTy->isDependentType() && 5388 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5389 InvalidDecl = true; 5390 5391 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5392 // than a variably modified type. 5393 if (!InvalidDecl && T->isVariablyModifiedType()) { 5394 bool SizeIsNegative; 5395 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5396 SizeIsNegative); 5397 if (!FixedTy.isNull()) { 5398 Diag(Loc, diag::warn_illegal_constant_array_size); 5399 T = FixedTy; 5400 } else { 5401 if (SizeIsNegative) 5402 Diag(Loc, diag::err_typecheck_negative_array_size); 5403 else 5404 Diag(Loc, diag::err_typecheck_field_variable_size); 5405 InvalidDecl = true; 5406 } 5407 } 5408 5409 // Fields can not have abstract class types 5410 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5411 diag::err_abstract_type_in_decl, 5412 AbstractFieldType)) 5413 InvalidDecl = true; 5414 5415 bool ZeroWidth = false; 5416 // If this is declared as a bit-field, check the bit-field. 5417 if (!InvalidDecl && BitWidth && 5418 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5419 InvalidDecl = true; 5420 DeleteExpr(BitWidth); 5421 BitWidth = 0; 5422 ZeroWidth = false; 5423 } 5424 5425 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5426 BitWidth, Mutable); 5427 if (InvalidDecl) 5428 NewFD->setInvalidDecl(); 5429 5430 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5431 Diag(Loc, diag::err_duplicate_member) << II; 5432 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5433 NewFD->setInvalidDecl(); 5434 } 5435 5436 if (getLangOptions().CPlusPlus) { 5437 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5438 5439 if (!T->isPODType()) 5440 CXXRecord->setPOD(false); 5441 if (!ZeroWidth) 5442 CXXRecord->setEmpty(false); 5443 5444 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5445 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5446 5447 if (!RDecl->hasTrivialConstructor()) 5448 CXXRecord->setHasTrivialConstructor(false); 5449 if (!RDecl->hasTrivialCopyConstructor()) 5450 CXXRecord->setHasTrivialCopyConstructor(false); 5451 if (!RDecl->hasTrivialCopyAssignment()) 5452 CXXRecord->setHasTrivialCopyAssignment(false); 5453 if (!RDecl->hasTrivialDestructor()) 5454 CXXRecord->setHasTrivialDestructor(false); 5455 5456 // C++ 9.5p1: An object of a class with a non-trivial 5457 // constructor, a non-trivial copy constructor, a non-trivial 5458 // destructor, or a non-trivial copy assignment operator 5459 // cannot be a member of a union, nor can an array of such 5460 // objects. 5461 // TODO: C++0x alters this restriction significantly. 5462 if (Record->isUnion()) { 5463 // We check for copy constructors before constructors 5464 // because otherwise we'll never get complaints about 5465 // copy constructors. 5466 5467 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5468 5469 CXXSpecialMember member; 5470 if (!RDecl->hasTrivialCopyConstructor()) 5471 member = CXXCopyConstructor; 5472 else if (!RDecl->hasTrivialConstructor()) 5473 member = CXXDefaultConstructor; 5474 else if (!RDecl->hasTrivialCopyAssignment()) 5475 member = CXXCopyAssignment; 5476 else if (!RDecl->hasTrivialDestructor()) 5477 member = CXXDestructor; 5478 else 5479 member = invalid; 5480 5481 if (member != invalid) { 5482 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5483 DiagnoseNontrivial(RT, member); 5484 NewFD->setInvalidDecl(); 5485 } 5486 } 5487 } 5488 } 5489 5490 // FIXME: We need to pass in the attributes given an AST 5491 // representation, not a parser representation. 5492 if (D) 5493 // FIXME: What to pass instead of TUScope? 5494 ProcessDeclAttributes(TUScope, NewFD, *D); 5495 5496 if (T.isObjCGCWeak()) 5497 Diag(Loc, diag::warn_attribute_weak_on_field); 5498 5499 NewFD->setAccess(AS); 5500 5501 // C++ [dcl.init.aggr]p1: 5502 // An aggregate is an array or a class (clause 9) with [...] no 5503 // private or protected non-static data members (clause 11). 5504 // A POD must be an aggregate. 5505 if (getLangOptions().CPlusPlus && 5506 (AS == AS_private || AS == AS_protected)) { 5507 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5508 CXXRecord->setAggregate(false); 5509 CXXRecord->setPOD(false); 5510 } 5511 5512 return NewFD; 5513} 5514 5515/// DiagnoseNontrivial - Given that a class has a non-trivial 5516/// special member, figure out why. 5517void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5518 QualType QT(T, 0U); 5519 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5520 5521 // Check whether the member was user-declared. 5522 switch (member) { 5523 case CXXDefaultConstructor: 5524 if (RD->hasUserDeclaredConstructor()) { 5525 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5526 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5527 const FunctionDecl *body = 0; 5528 ci->getBody(body); 5529 if (!body || 5530 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5531 SourceLocation CtorLoc = ci->getLocation(); 5532 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5533 return; 5534 } 5535 } 5536 5537 assert(0 && "found no user-declared constructors"); 5538 return; 5539 } 5540 break; 5541 5542 case CXXCopyConstructor: 5543 if (RD->hasUserDeclaredCopyConstructor()) { 5544 SourceLocation CtorLoc = 5545 RD->getCopyConstructor(Context, 0)->getLocation(); 5546 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5547 return; 5548 } 5549 break; 5550 5551 case CXXCopyAssignment: 5552 if (RD->hasUserDeclaredCopyAssignment()) { 5553 // FIXME: this should use the location of the copy 5554 // assignment, not the type. 5555 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5556 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5557 return; 5558 } 5559 break; 5560 5561 case CXXDestructor: 5562 if (RD->hasUserDeclaredDestructor()) { 5563 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5564 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5565 return; 5566 } 5567 break; 5568 } 5569 5570 typedef CXXRecordDecl::base_class_iterator base_iter; 5571 5572 // Virtual bases and members inhibit trivial copying/construction, 5573 // but not trivial destruction. 5574 if (member != CXXDestructor) { 5575 // Check for virtual bases. vbases includes indirect virtual bases, 5576 // so we just iterate through the direct bases. 5577 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5578 if (bi->isVirtual()) { 5579 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5580 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5581 return; 5582 } 5583 5584 // Check for virtual methods. 5585 typedef CXXRecordDecl::method_iterator meth_iter; 5586 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5587 ++mi) { 5588 if (mi->isVirtual()) { 5589 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5590 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5591 return; 5592 } 5593 } 5594 } 5595 5596 bool (CXXRecordDecl::*hasTrivial)() const; 5597 switch (member) { 5598 case CXXDefaultConstructor: 5599 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5600 case CXXCopyConstructor: 5601 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5602 case CXXCopyAssignment: 5603 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5604 case CXXDestructor: 5605 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5606 default: 5607 assert(0 && "unexpected special member"); return; 5608 } 5609 5610 // Check for nontrivial bases (and recurse). 5611 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5612 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5613 assert(BaseRT && "Don't know how to handle dependent bases"); 5614 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5615 if (!(BaseRecTy->*hasTrivial)()) { 5616 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5617 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5618 DiagnoseNontrivial(BaseRT, member); 5619 return; 5620 } 5621 } 5622 5623 // Check for nontrivial members (and recurse). 5624 typedef RecordDecl::field_iterator field_iter; 5625 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5626 ++fi) { 5627 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5628 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5629 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5630 5631 if (!(EltRD->*hasTrivial)()) { 5632 SourceLocation FLoc = (*fi)->getLocation(); 5633 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5634 DiagnoseNontrivial(EltRT, member); 5635 return; 5636 } 5637 } 5638 } 5639 5640 assert(0 && "found no explanation for non-trivial member"); 5641} 5642 5643/// TranslateIvarVisibility - Translate visibility from a token ID to an 5644/// AST enum value. 5645static ObjCIvarDecl::AccessControl 5646TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5647 switch (ivarVisibility) { 5648 default: assert(0 && "Unknown visitibility kind"); 5649 case tok::objc_private: return ObjCIvarDecl::Private; 5650 case tok::objc_public: return ObjCIvarDecl::Public; 5651 case tok::objc_protected: return ObjCIvarDecl::Protected; 5652 case tok::objc_package: return ObjCIvarDecl::Package; 5653 } 5654} 5655 5656/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5657/// in order to create an IvarDecl object for it. 5658Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5659 SourceLocation DeclStart, 5660 DeclPtrTy IntfDecl, 5661 Declarator &D, ExprTy *BitfieldWidth, 5662 tok::ObjCKeywordKind Visibility) { 5663 5664 IdentifierInfo *II = D.getIdentifier(); 5665 Expr *BitWidth = (Expr*)BitfieldWidth; 5666 SourceLocation Loc = DeclStart; 5667 if (II) Loc = D.getIdentifierLoc(); 5668 5669 // FIXME: Unnamed fields can be handled in various different ways, for 5670 // example, unnamed unions inject all members into the struct namespace! 5671 5672 TypeSourceInfo *TInfo = 0; 5673 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5674 5675 if (BitWidth) { 5676 // 6.7.2.1p3, 6.7.2.1p4 5677 if (VerifyBitField(Loc, II, T, BitWidth)) { 5678 D.setInvalidType(); 5679 DeleteExpr(BitWidth); 5680 BitWidth = 0; 5681 } 5682 } else { 5683 // Not a bitfield. 5684 5685 // validate II. 5686 5687 } 5688 5689 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5690 // than a variably modified type. 5691 if (T->isVariablyModifiedType()) { 5692 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5693 D.setInvalidType(); 5694 } 5695 5696 // Get the visibility (access control) for this ivar. 5697 ObjCIvarDecl::AccessControl ac = 5698 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5699 : ObjCIvarDecl::None; 5700 // Must set ivar's DeclContext to its enclosing interface. 5701 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5702 DeclContext *EnclosingContext; 5703 if (ObjCImplementationDecl *IMPDecl = 5704 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5705 // Case of ivar declared in an implementation. Context is that of its class. 5706 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5707 assert(IDecl && "No class- ActOnIvar"); 5708 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5709 } else 5710 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5711 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5712 5713 // Construct the decl. 5714 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5715 EnclosingContext, Loc, II, T, 5716 TInfo, ac, (Expr *)BitfieldWidth); 5717 5718 if (II) { 5719 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5720 ForRedeclaration); 5721 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5722 && !isa<TagDecl>(PrevDecl)) { 5723 Diag(Loc, diag::err_duplicate_member) << II; 5724 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5725 NewID->setInvalidDecl(); 5726 } 5727 } 5728 5729 // Process attributes attached to the ivar. 5730 ProcessDeclAttributes(S, NewID, D); 5731 5732 if (D.isInvalidType()) 5733 NewID->setInvalidDecl(); 5734 5735 if (II) { 5736 // FIXME: When interfaces are DeclContexts, we'll need to add 5737 // these to the interface. 5738 S->AddDecl(DeclPtrTy::make(NewID)); 5739 IdResolver.AddDecl(NewID); 5740 } 5741 5742 return DeclPtrTy::make(NewID); 5743} 5744 5745void Sema::ActOnFields(Scope* S, 5746 SourceLocation RecLoc, DeclPtrTy RecDecl, 5747 DeclPtrTy *Fields, unsigned NumFields, 5748 SourceLocation LBrac, SourceLocation RBrac, 5749 AttributeList *Attr) { 5750 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5751 assert(EnclosingDecl && "missing record or interface decl"); 5752 5753 // If the decl this is being inserted into is invalid, then it may be a 5754 // redeclaration or some other bogus case. Don't try to add fields to it. 5755 if (EnclosingDecl->isInvalidDecl()) { 5756 // FIXME: Deallocate fields? 5757 return; 5758 } 5759 5760 5761 // Verify that all the fields are okay. 5762 unsigned NumNamedMembers = 0; 5763 llvm::SmallVector<FieldDecl*, 32> RecFields; 5764 5765 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5766 for (unsigned i = 0; i != NumFields; ++i) { 5767 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5768 5769 // Get the type for the field. 5770 Type *FDTy = FD->getType().getTypePtr(); 5771 5772 if (!FD->isAnonymousStructOrUnion()) { 5773 // Remember all fields written by the user. 5774 RecFields.push_back(FD); 5775 } 5776 5777 // If the field is already invalid for some reason, don't emit more 5778 // diagnostics about it. 5779 if (FD->isInvalidDecl()) { 5780 EnclosingDecl->setInvalidDecl(); 5781 continue; 5782 } 5783 5784 // C99 6.7.2.1p2: 5785 // A structure or union shall not contain a member with 5786 // incomplete or function type (hence, a structure shall not 5787 // contain an instance of itself, but may contain a pointer to 5788 // an instance of itself), except that the last member of a 5789 // structure with more than one named member may have incomplete 5790 // array type; such a structure (and any union containing, 5791 // possibly recursively, a member that is such a structure) 5792 // shall not be a member of a structure or an element of an 5793 // array. 5794 if (FDTy->isFunctionType()) { 5795 // Field declared as a function. 5796 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5797 << FD->getDeclName(); 5798 FD->setInvalidDecl(); 5799 EnclosingDecl->setInvalidDecl(); 5800 continue; 5801 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5802 Record && Record->isStruct()) { 5803 // Flexible array member. 5804 if (NumNamedMembers < 1) { 5805 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5806 << FD->getDeclName(); 5807 FD->setInvalidDecl(); 5808 EnclosingDecl->setInvalidDecl(); 5809 continue; 5810 } 5811 // Okay, we have a legal flexible array member at the end of the struct. 5812 if (Record) 5813 Record->setHasFlexibleArrayMember(true); 5814 } else if (!FDTy->isDependentType() && 5815 RequireCompleteType(FD->getLocation(), FD->getType(), 5816 diag::err_field_incomplete)) { 5817 // Incomplete type 5818 FD->setInvalidDecl(); 5819 EnclosingDecl->setInvalidDecl(); 5820 continue; 5821 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5822 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5823 // If this is a member of a union, then entire union becomes "flexible". 5824 if (Record && Record->isUnion()) { 5825 Record->setHasFlexibleArrayMember(true); 5826 } else { 5827 // If this is a struct/class and this is not the last element, reject 5828 // it. Note that GCC supports variable sized arrays in the middle of 5829 // structures. 5830 if (i != NumFields-1) 5831 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5832 << FD->getDeclName() << FD->getType(); 5833 else { 5834 // We support flexible arrays at the end of structs in 5835 // other structs as an extension. 5836 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5837 << FD->getDeclName(); 5838 if (Record) 5839 Record->setHasFlexibleArrayMember(true); 5840 } 5841 } 5842 } 5843 if (Record && FDTTy->getDecl()->hasObjectMember()) 5844 Record->setHasObjectMember(true); 5845 } else if (FDTy->isObjCInterfaceType()) { 5846 /// A field cannot be an Objective-c object 5847 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5848 FD->setInvalidDecl(); 5849 EnclosingDecl->setInvalidDecl(); 5850 continue; 5851 } else if (getLangOptions().ObjC1 && 5852 getLangOptions().getGCMode() != LangOptions::NonGC && 5853 Record && 5854 (FD->getType()->isObjCObjectPointerType() || 5855 FD->getType().isObjCGCStrong())) 5856 Record->setHasObjectMember(true); 5857 // Keep track of the number of named members. 5858 if (FD->getIdentifier()) 5859 ++NumNamedMembers; 5860 } 5861 5862 // Okay, we successfully defined 'Record'. 5863 if (Record) { 5864 Record->completeDefinition(Context); 5865 } else { 5866 ObjCIvarDecl **ClsFields = 5867 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5868 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5869 ID->setIVarList(ClsFields, RecFields.size(), Context); 5870 ID->setLocEnd(RBrac); 5871 // Add ivar's to class's DeclContext. 5872 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5873 ClsFields[i]->setLexicalDeclContext(ID); 5874 ID->addDecl(ClsFields[i]); 5875 } 5876 // Must enforce the rule that ivars in the base classes may not be 5877 // duplicates. 5878 if (ID->getSuperClass()) { 5879 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5880 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5881 ObjCIvarDecl* Ivar = (*IVI); 5882 5883 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5884 ObjCIvarDecl* prevIvar = 5885 ID->getSuperClass()->lookupInstanceVariable(II); 5886 if (prevIvar) { 5887 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5888 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5889 } 5890 } 5891 } 5892 } 5893 } else if (ObjCImplementationDecl *IMPDecl = 5894 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5895 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5896 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5897 // Ivar declared in @implementation never belongs to the implementation. 5898 // Only it is in implementation's lexical context. 5899 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5900 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5901 } 5902 } 5903 5904 if (Attr) 5905 ProcessDeclAttributeList(S, Record, Attr); 5906} 5907 5908EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5909 EnumConstantDecl *LastEnumConst, 5910 SourceLocation IdLoc, 5911 IdentifierInfo *Id, 5912 ExprArg val) { 5913 Expr *Val = (Expr *)val.get(); 5914 5915 llvm::APSInt EnumVal(32); 5916 QualType EltTy; 5917 if (Val) { 5918 if (Enum->isDependentType()) 5919 EltTy = Context.DependentTy; 5920 else { 5921 // Make sure to promote the operand type to int. 5922 UsualUnaryConversions(Val); 5923 if (Val != val.get()) { 5924 val.release(); 5925 val = Val; 5926 } 5927 5928 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5929 SourceLocation ExpLoc; 5930 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5931 Val = 0; 5932 } else { 5933 EltTy = Val->getType(); 5934 } 5935 } 5936 } 5937 5938 if (!Val) { 5939 if (Enum->isDependentType()) 5940 EltTy = Context.DependentTy; 5941 else if (LastEnumConst) { 5942 // Assign the last value + 1. 5943 EnumVal = LastEnumConst->getInitVal(); 5944 ++EnumVal; 5945 5946 // Check for overflow on increment. 5947 if (EnumVal < LastEnumConst->getInitVal()) 5948 Diag(IdLoc, diag::warn_enum_value_overflow); 5949 5950 EltTy = LastEnumConst->getType(); 5951 } else { 5952 // First value, set to zero. 5953 EltTy = Context.IntTy; 5954 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5955 EnumVal.setIsSigned(true); 5956 } 5957 } 5958 5959 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5960 5961 val.release(); 5962 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5963 Val, EnumVal); 5964} 5965 5966 5967Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5968 DeclPtrTy lastEnumConst, 5969 SourceLocation IdLoc, 5970 IdentifierInfo *Id, 5971 SourceLocation EqualLoc, ExprTy *val) { 5972 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5973 EnumConstantDecl *LastEnumConst = 5974 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5975 Expr *Val = static_cast<Expr*>(val); 5976 5977 // The scope passed in may not be a decl scope. Zip up the scope tree until 5978 // we find one that is. 5979 S = getNonFieldDeclScope(S); 5980 5981 // Verify that there isn't already something declared with this name in this 5982 // scope. 5983 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5984 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5985 // Maybe we will complain about the shadowed template parameter. 5986 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5987 // Just pretend that we didn't see the previous declaration. 5988 PrevDecl = 0; 5989 } 5990 5991 if (PrevDecl) { 5992 // When in C++, we may get a TagDecl with the same name; in this case the 5993 // enum constant will 'hide' the tag. 5994 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5995 "Received TagDecl when not in C++!"); 5996 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5997 if (isa<EnumConstantDecl>(PrevDecl)) 5998 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5999 else 6000 Diag(IdLoc, diag::err_redefinition) << Id; 6001 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6002 if (Val) Val->Destroy(Context); 6003 return DeclPtrTy(); 6004 } 6005 } 6006 6007 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6008 IdLoc, Id, Owned(Val)); 6009 6010 // Register this decl in the current scope stack. 6011 if (New) 6012 PushOnScopeChains(New, S); 6013 6014 return DeclPtrTy::make(New); 6015} 6016 6017void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6018 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6019 DeclPtrTy *Elements, unsigned NumElements, 6020 Scope *S, AttributeList *Attr) { 6021 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6022 QualType EnumType = Context.getTypeDeclType(Enum); 6023 6024 if (Attr) 6025 ProcessDeclAttributeList(S, Enum, Attr); 6026 6027 if (Enum->isDependentType()) { 6028 for (unsigned i = 0; i != NumElements; ++i) { 6029 EnumConstantDecl *ECD = 6030 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6031 if (!ECD) continue; 6032 6033 ECD->setType(EnumType); 6034 } 6035 6036 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 6037 return; 6038 } 6039 6040 // TODO: If the result value doesn't fit in an int, it must be a long or long 6041 // long value. ISO C does not support this, but GCC does as an extension, 6042 // emit a warning. 6043 unsigned IntWidth = Context.Target.getIntWidth(); 6044 unsigned CharWidth = Context.Target.getCharWidth(); 6045 unsigned ShortWidth = Context.Target.getShortWidth(); 6046 6047 // Verify that all the values are okay, compute the size of the values, and 6048 // reverse the list. 6049 unsigned NumNegativeBits = 0; 6050 unsigned NumPositiveBits = 0; 6051 6052 // Keep track of whether all elements have type int. 6053 bool AllElementsInt = true; 6054 6055 for (unsigned i = 0; i != NumElements; ++i) { 6056 EnumConstantDecl *ECD = 6057 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6058 if (!ECD) continue; // Already issued a diagnostic. 6059 6060 // If the enum value doesn't fit in an int, emit an extension warning. 6061 const llvm::APSInt &InitVal = ECD->getInitVal(); 6062 assert(InitVal.getBitWidth() >= IntWidth && 6063 "Should have promoted value to int"); 6064 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 6065 llvm::APSInt V(InitVal); 6066 V.trunc(IntWidth); 6067 V.extend(InitVal.getBitWidth()); 6068 if (V != InitVal) 6069 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 6070 << InitVal.toString(10); 6071 } 6072 6073 // Keep track of the size of positive and negative values. 6074 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6075 NumPositiveBits = std::max(NumPositiveBits, 6076 (unsigned)InitVal.getActiveBits()); 6077 else 6078 NumNegativeBits = std::max(NumNegativeBits, 6079 (unsigned)InitVal.getMinSignedBits()); 6080 6081 // Keep track of whether every enum element has type int (very commmon). 6082 if (AllElementsInt) 6083 AllElementsInt = ECD->getType() == Context.IntTy; 6084 } 6085 6086 // Figure out the type that should be used for this enum. 6087 // FIXME: Support -fshort-enums. 6088 QualType BestType; 6089 unsigned BestWidth; 6090 6091 // C++0x N3000 [conv.prom]p3: 6092 // An rvalue of an unscoped enumeration type whose underlying 6093 // type is not fixed can be converted to an rvalue of the first 6094 // of the following types that can represent all the values of 6095 // the enumeration: int, unsigned int, long int, unsigned long 6096 // int, long long int, or unsigned long long int. 6097 // C99 6.4.4.3p2: 6098 // An identifier declared as an enumeration constant has type int. 6099 // The C99 rule is modified by a gcc extension 6100 QualType BestPromotionType; 6101 6102 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6103 6104 if (NumNegativeBits) { 6105 // If there is a negative value, figure out the smallest integer type (of 6106 // int/long/longlong) that fits. 6107 // If it's packed, check also if it fits a char or a short. 6108 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6109 BestType = Context.SignedCharTy; 6110 BestWidth = CharWidth; 6111 } else if (Packed && NumNegativeBits <= ShortWidth && 6112 NumPositiveBits < ShortWidth) { 6113 BestType = Context.ShortTy; 6114 BestWidth = ShortWidth; 6115 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6116 BestType = Context.IntTy; 6117 BestWidth = IntWidth; 6118 } else { 6119 BestWidth = Context.Target.getLongWidth(); 6120 6121 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6122 BestType = Context.LongTy; 6123 } else { 6124 BestWidth = Context.Target.getLongLongWidth(); 6125 6126 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6127 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6128 BestType = Context.LongLongTy; 6129 } 6130 } 6131 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6132 } else { 6133 // If there is no negative value, figure out which of uint, ulong, ulonglong 6134 // fits. 6135 // If it's packed, check also if it fits a char or a short. 6136 if (Packed && NumPositiveBits <= CharWidth) { 6137 BestType = Context.UnsignedCharTy; 6138 BestPromotionType = Context.IntTy; 6139 BestWidth = CharWidth; 6140 } else if (Packed && NumPositiveBits <= ShortWidth) { 6141 BestType = Context.UnsignedShortTy; 6142 BestPromotionType = Context.IntTy; 6143 BestWidth = ShortWidth; 6144 } else if (NumPositiveBits <= IntWidth) { 6145 BestType = Context.UnsignedIntTy; 6146 BestWidth = IntWidth; 6147 BestPromotionType = (NumPositiveBits == BestWidth 6148 ? Context.UnsignedIntTy : Context.IntTy); 6149 } else if (NumPositiveBits <= 6150 (BestWidth = Context.Target.getLongWidth())) { 6151 BestType = Context.UnsignedLongTy; 6152 BestPromotionType = (NumPositiveBits == BestWidth 6153 ? Context.UnsignedLongTy : Context.LongTy); 6154 } else { 6155 BestWidth = Context.Target.getLongLongWidth(); 6156 assert(NumPositiveBits <= BestWidth && 6157 "How could an initializer get larger than ULL?"); 6158 BestType = Context.UnsignedLongLongTy; 6159 BestPromotionType = (NumPositiveBits == BestWidth 6160 ? Context.UnsignedLongLongTy : Context.LongLongTy); 6161 } 6162 } 6163 6164 // If we're in C and the promotion type is larger than an int, just 6165 // use the underlying type, which is generally the unsigned integer 6166 // type of the same rank as the promotion type. This is how the gcc 6167 // extension works. 6168 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 6169 BestPromotionType = BestType; 6170 6171 // Loop over all of the enumerator constants, changing their types to match 6172 // the type of the enum if needed. 6173 for (unsigned i = 0; i != NumElements; ++i) { 6174 EnumConstantDecl *ECD = 6175 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6176 if (!ECD) continue; // Already issued a diagnostic. 6177 6178 // Standard C says the enumerators have int type, but we allow, as an 6179 // extension, the enumerators to be larger than int size. If each 6180 // enumerator value fits in an int, type it as an int, otherwise type it the 6181 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6182 // that X has type 'int', not 'unsigned'. 6183 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 6184 continue; 6185 6186 // Determine whether the value fits into an int. 6187 llvm::APSInt InitVal = ECD->getInitVal(); 6188 bool FitsInInt; 6189 if (InitVal.isUnsigned() || !InitVal.isNegative()) 6190 FitsInInt = InitVal.getActiveBits() < IntWidth; 6191 else 6192 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 6193 6194 // If it fits into an integer type, force it. Otherwise force it to match 6195 // the enum decl type. 6196 QualType NewTy; 6197 unsigned NewWidth; 6198 bool NewSign; 6199 if (FitsInInt && !getLangOptions().CPlusPlus) { 6200 NewTy = Context.IntTy; 6201 NewWidth = IntWidth; 6202 NewSign = true; 6203 } else if (ECD->getType() == BestType) { 6204 // Already the right type! 6205 if (getLangOptions().CPlusPlus) 6206 // C++ [dcl.enum]p4: Following the closing brace of an 6207 // enum-specifier, each enumerator has the type of its 6208 // enumeration. 6209 ECD->setType(EnumType); 6210 continue; 6211 } else { 6212 NewTy = BestType; 6213 NewWidth = BestWidth; 6214 NewSign = BestType->isSignedIntegerType(); 6215 } 6216 6217 // Adjust the APSInt value. 6218 InitVal.extOrTrunc(NewWidth); 6219 InitVal.setIsSigned(NewSign); 6220 ECD->setInitVal(InitVal); 6221 6222 // Adjust the Expr initializer and type. 6223 if (ECD->getInitExpr()) 6224 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6225 CastExpr::CK_IntegralCast, 6226 ECD->getInitExpr(), 6227 /*isLvalue=*/false)); 6228 if (getLangOptions().CPlusPlus) 6229 // C++ [dcl.enum]p4: Following the closing brace of an 6230 // enum-specifier, each enumerator has the type of its 6231 // enumeration. 6232 ECD->setType(EnumType); 6233 else 6234 ECD->setType(NewTy); 6235 } 6236 6237 Enum->completeDefinition(Context, BestType, BestPromotionType); 6238} 6239 6240Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6241 ExprArg expr) { 6242 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6243 6244 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6245 Loc, AsmString); 6246 CurContext->addDecl(New); 6247 return DeclPtrTy::make(New); 6248} 6249 6250void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6251 SourceLocation PragmaLoc, 6252 SourceLocation NameLoc) { 6253 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6254 6255 if (PrevDecl) { 6256 PrevDecl->addAttr(::new (Context) WeakAttr()); 6257 } else { 6258 (void)WeakUndeclaredIdentifiers.insert( 6259 std::pair<IdentifierInfo*,WeakInfo> 6260 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6261 } 6262} 6263 6264void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6265 IdentifierInfo* AliasName, 6266 SourceLocation PragmaLoc, 6267 SourceLocation NameLoc, 6268 SourceLocation AliasNameLoc) { 6269 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6270 WeakInfo W = WeakInfo(Name, NameLoc); 6271 6272 if (PrevDecl) { 6273 if (!PrevDecl->hasAttr<AliasAttr>()) 6274 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6275 DeclApplyPragmaWeak(TUScope, ND, W); 6276 } else { 6277 (void)WeakUndeclaredIdentifiers.insert( 6278 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6279 } 6280} 6281