SemaDecl.cpp revision 90b68203fe13ee160281fb1bf42a880d4ba8b688
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/Analysis/PathSensitive/AnalysisContext.h" 18#include "clang/AST/APValue.h" 19#include "clang/AST/ASTConsumer.h" 20#include "clang/AST/ASTContext.h" 21#include "clang/Analysis/CFG.h" 22#include "clang/AST/CXXInheritance.h" 23#include "clang/AST/DeclObjC.h" 24#include "clang/AST/DeclTemplate.h" 25#include "clang/AST/ExprCXX.h" 26#include "clang/AST/StmtCXX.h" 27#include "clang/AST/StmtObjC.h" 28#include "clang/Parse/DeclSpec.h" 29#include "clang/Parse/ParseDiagnostic.h" 30#include "clang/Parse/Template.h" 31#include "clang/Basic/PartialDiagnostic.h" 32#include "clang/Basic/SourceManager.h" 33#include "clang/Basic/TargetInfo.h" 34// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 35#include "clang/Lex/Preprocessor.h" 36#include "clang/Lex/HeaderSearch.h" 37#include "llvm/ADT/BitVector.h" 38#include "llvm/ADT/STLExtras.h" 39#include "llvm/ADT/Triple.h" 40#include <algorithm> 41#include <cstring> 42#include <functional> 43#include <queue> 44using namespace clang; 45 46/// getDeclName - Return a pretty name for the specified decl if possible, or 47/// an empty string if not. This is used for pretty crash reporting. 48std::string Sema::getDeclName(DeclPtrTy d) { 49 Decl *D = d.getAs<Decl>(); 50 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 51 return DN->getQualifiedNameAsString(); 52 return ""; 53} 54 55Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 56 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 57} 58 59/// \brief If the identifier refers to a type name within this scope, 60/// return the declaration of that type. 61/// 62/// This routine performs ordinary name lookup of the identifier II 63/// within the given scope, with optional C++ scope specifier SS, to 64/// determine whether the name refers to a type. If so, returns an 65/// opaque pointer (actually a QualType) corresponding to that 66/// type. Otherwise, returns NULL. 67/// 68/// If name lookup results in an ambiguity, this routine will complain 69/// and then return NULL. 70Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 71 Scope *S, const CXXScopeSpec *SS, 72 bool isClassName, 73 TypeTy *ObjectTypePtr) { 74 // Determine where we will perform name lookup. 75 DeclContext *LookupCtx = 0; 76 if (ObjectTypePtr) { 77 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 78 if (ObjectType->isRecordType()) 79 LookupCtx = computeDeclContext(ObjectType); 80 } else if (SS && SS->isSet()) { 81 LookupCtx = computeDeclContext(*SS, false); 82 83 if (!LookupCtx) { 84 if (isDependentScopeSpecifier(*SS)) { 85 // C++ [temp.res]p3: 86 // A qualified-id that refers to a type and in which the 87 // nested-name-specifier depends on a template-parameter (14.6.2) 88 // shall be prefixed by the keyword typename to indicate that the 89 // qualified-id denotes a type, forming an 90 // elaborated-type-specifier (7.1.5.3). 91 // 92 // We therefore do not perform any name lookup if the result would 93 // refer to a member of an unknown specialization. 94 if (!isClassName) 95 return 0; 96 97 // We know from the grammar that this name refers to a type, so build a 98 // TypenameType node to describe the type. 99 // FIXME: Record somewhere that this TypenameType node has no "typename" 100 // keyword associated with it. 101 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 102 II, SS->getRange()).getAsOpaquePtr(); 103 } 104 105 return 0; 106 } 107 108 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 109 return 0; 110 } 111 112 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 113 // lookup for class-names. 114 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 115 LookupOrdinaryName; 116 LookupResult Result(*this, &II, NameLoc, Kind); 117 if (LookupCtx) { 118 // Perform "qualified" name lookup into the declaration context we 119 // computed, which is either the type of the base of a member access 120 // expression or the declaration context associated with a prior 121 // nested-name-specifier. 122 LookupQualifiedName(Result, LookupCtx); 123 124 if (ObjectTypePtr && Result.empty()) { 125 // C++ [basic.lookup.classref]p3: 126 // If the unqualified-id is ~type-name, the type-name is looked up 127 // in the context of the entire postfix-expression. If the type T of 128 // the object expression is of a class type C, the type-name is also 129 // looked up in the scope of class C. At least one of the lookups shall 130 // find a name that refers to (possibly cv-qualified) T. 131 LookupName(Result, S); 132 } 133 } else { 134 // Perform unqualified name lookup. 135 LookupName(Result, S); 136 } 137 138 NamedDecl *IIDecl = 0; 139 switch (Result.getResultKind()) { 140 case LookupResult::NotFound: 141 case LookupResult::NotFoundInCurrentInstantiation: 142 case LookupResult::FoundOverloaded: 143 case LookupResult::FoundUnresolvedValue: 144 return 0; 145 146 case LookupResult::Ambiguous: 147 // Recover from type-hiding ambiguities by hiding the type. We'll 148 // do the lookup again when looking for an object, and we can 149 // diagnose the error then. If we don't do this, then the error 150 // about hiding the type will be immediately followed by an error 151 // that only makes sense if the identifier was treated like a type. 152 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 153 Result.suppressDiagnostics(); 154 return 0; 155 } 156 157 // Look to see if we have a type anywhere in the list of results. 158 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 159 Res != ResEnd; ++Res) { 160 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 161 if (!IIDecl || 162 (*Res)->getLocation().getRawEncoding() < 163 IIDecl->getLocation().getRawEncoding()) 164 IIDecl = *Res; 165 } 166 } 167 168 if (!IIDecl) { 169 // None of the entities we found is a type, so there is no way 170 // to even assume that the result is a type. In this case, don't 171 // complain about the ambiguity. The parser will either try to 172 // perform this lookup again (e.g., as an object name), which 173 // will produce the ambiguity, or will complain that it expected 174 // a type name. 175 Result.suppressDiagnostics(); 176 return 0; 177 } 178 179 // We found a type within the ambiguous lookup; diagnose the 180 // ambiguity and then return that type. This might be the right 181 // answer, or it might not be, but it suppresses any attempt to 182 // perform the name lookup again. 183 break; 184 185 case LookupResult::Found: 186 IIDecl = Result.getFoundDecl(); 187 break; 188 } 189 190 assert(IIDecl && "Didn't find decl"); 191 192 QualType T; 193 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 194 DiagnoseUseOfDecl(IIDecl, NameLoc); 195 196 // C++ [temp.local]p2: 197 // Within the scope of a class template specialization or 198 // partial specialization, when the injected-class-name is 199 // not followed by a <, it is equivalent to the 200 // injected-class-name followed by the template-argument s 201 // of the class template specialization or partial 202 // specialization enclosed in <>. 203 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 204 if (RD->isInjectedClassName()) 205 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 206 T = Template->getInjectedClassNameType(Context); 207 208 if (T.isNull()) 209 T = Context.getTypeDeclType(TD); 210 211 if (SS) 212 T = getQualifiedNameType(*SS, T); 213 214 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 215 T = Context.getObjCInterfaceType(IDecl); 216 } else if (UnresolvedUsingTypenameDecl *UUDecl = 217 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 218 // FIXME: preserve source structure information. 219 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 220 } else { 221 // If it's not plausibly a type, suppress diagnostics. 222 Result.suppressDiagnostics(); 223 return 0; 224 } 225 226 return T.getAsOpaquePtr(); 227} 228 229/// isTagName() - This method is called *for error recovery purposes only* 230/// to determine if the specified name is a valid tag name ("struct foo"). If 231/// so, this returns the TST for the tag corresponding to it (TST_enum, 232/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 233/// where the user forgot to specify the tag. 234DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 235 // Do a tag name lookup in this scope. 236 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 237 LookupName(R, S, false); 238 R.suppressDiagnostics(); 239 if (R.getResultKind() == LookupResult::Found) 240 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 241 switch (TD->getTagKind()) { 242 case TagDecl::TK_struct: return DeclSpec::TST_struct; 243 case TagDecl::TK_union: return DeclSpec::TST_union; 244 case TagDecl::TK_class: return DeclSpec::TST_class; 245 case TagDecl::TK_enum: return DeclSpec::TST_enum; 246 } 247 } 248 249 return DeclSpec::TST_unspecified; 250} 251 252bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 253 SourceLocation IILoc, 254 Scope *S, 255 const CXXScopeSpec *SS, 256 TypeTy *&SuggestedType) { 257 // We don't have anything to suggest (yet). 258 SuggestedType = 0; 259 260 // There may have been a typo in the name of the type. Look up typo 261 // results, in case we have something that we can suggest. 262 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 263 NotForRedeclaration); 264 265 // FIXME: It would be nice if we could correct for typos in built-in 266 // names, such as "itn" for "int". 267 268 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 269 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 270 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 271 !Result->isInvalidDecl()) { 272 // We found a similarly-named type or interface; suggest that. 273 if (!SS || !SS->isSet()) 274 Diag(IILoc, diag::err_unknown_typename_suggest) 275 << &II << Lookup.getLookupName() 276 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 277 Result->getNameAsString()); 278 else if (DeclContext *DC = computeDeclContext(*SS, false)) 279 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 280 << &II << DC << Lookup.getLookupName() << SS->getRange() 281 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 282 Result->getNameAsString()); 283 else 284 llvm_unreachable("could not have corrected a typo here"); 285 286 Diag(Result->getLocation(), diag::note_previous_decl) 287 << Result->getDeclName(); 288 289 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 290 return true; 291 } 292 } 293 294 // FIXME: Should we move the logic that tries to recover from a missing tag 295 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 296 297 if (!SS || (!SS->isSet() && !SS->isInvalid())) 298 Diag(IILoc, diag::err_unknown_typename) << &II; 299 else if (DeclContext *DC = computeDeclContext(*SS, false)) 300 Diag(IILoc, diag::err_typename_nested_not_found) 301 << &II << DC << SS->getRange(); 302 else if (isDependentScopeSpecifier(*SS)) { 303 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 304 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 305 << SourceRange(SS->getRange().getBegin(), IILoc) 306 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 307 "typename "); 308 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 309 } else { 310 assert(SS && SS->isInvalid() && 311 "Invalid scope specifier has already been diagnosed"); 312 } 313 314 return true; 315} 316 317// Determines the context to return to after temporarily entering a 318// context. This depends in an unnecessarily complicated way on the 319// exact ordering of callbacks from the parser. 320DeclContext *Sema::getContainingDC(DeclContext *DC) { 321 322 // Functions defined inline within classes aren't parsed until we've 323 // finished parsing the top-level class, so the top-level class is 324 // the context we'll need to return to. 325 if (isa<FunctionDecl>(DC)) { 326 DC = DC->getLexicalParent(); 327 328 // A function not defined within a class will always return to its 329 // lexical context. 330 if (!isa<CXXRecordDecl>(DC)) 331 return DC; 332 333 // A C++ inline method/friend is parsed *after* the topmost class 334 // it was declared in is fully parsed ("complete"); the topmost 335 // class is the context we need to return to. 336 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 337 DC = RD; 338 339 // Return the declaration context of the topmost class the inline method is 340 // declared in. 341 return DC; 342 } 343 344 if (isa<ObjCMethodDecl>(DC)) 345 return Context.getTranslationUnitDecl(); 346 347 return DC->getLexicalParent(); 348} 349 350void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 351 assert(getContainingDC(DC) == CurContext && 352 "The next DeclContext should be lexically contained in the current one."); 353 CurContext = DC; 354 S->setEntity(DC); 355} 356 357void Sema::PopDeclContext() { 358 assert(CurContext && "DeclContext imbalance!"); 359 360 CurContext = getContainingDC(CurContext); 361} 362 363/// EnterDeclaratorContext - Used when we must lookup names in the context 364/// of a declarator's nested name specifier. 365/// 366void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 367 // C++0x [basic.lookup.unqual]p13: 368 // A name used in the definition of a static data member of class 369 // X (after the qualified-id of the static member) is looked up as 370 // if the name was used in a member function of X. 371 // C++0x [basic.lookup.unqual]p14: 372 // If a variable member of a namespace is defined outside of the 373 // scope of its namespace then any name used in the definition of 374 // the variable member (after the declarator-id) is looked up as 375 // if the definition of the variable member occurred in its 376 // namespace. 377 // Both of these imply that we should push a scope whose context 378 // is the semantic context of the declaration. We can't use 379 // PushDeclContext here because that context is not necessarily 380 // lexically contained in the current context. Fortunately, 381 // the containing scope should have the appropriate information. 382 383 assert(!S->getEntity() && "scope already has entity"); 384 385#ifndef NDEBUG 386 Scope *Ancestor = S->getParent(); 387 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 388 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 389#endif 390 391 CurContext = DC; 392 S->setEntity(DC); 393} 394 395void Sema::ExitDeclaratorContext(Scope *S) { 396 assert(S->getEntity() == CurContext && "Context imbalance!"); 397 398 // Switch back to the lexical context. The safety of this is 399 // enforced by an assert in EnterDeclaratorContext. 400 Scope *Ancestor = S->getParent(); 401 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 402 CurContext = (DeclContext*) Ancestor->getEntity(); 403 404 // We don't need to do anything with the scope, which is going to 405 // disappear. 406} 407 408/// \brief Determine whether we allow overloading of the function 409/// PrevDecl with another declaration. 410/// 411/// This routine determines whether overloading is possible, not 412/// whether some new function is actually an overload. It will return 413/// true in C++ (where we can always provide overloads) or, as an 414/// extension, in C when the previous function is already an 415/// overloaded function declaration or has the "overloadable" 416/// attribute. 417static bool AllowOverloadingOfFunction(LookupResult &Previous, 418 ASTContext &Context) { 419 if (Context.getLangOptions().CPlusPlus) 420 return true; 421 422 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 423 return true; 424 425 return (Previous.getResultKind() == LookupResult::Found 426 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 427} 428 429/// Add this decl to the scope shadowed decl chains. 430void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 431 // Move up the scope chain until we find the nearest enclosing 432 // non-transparent context. The declaration will be introduced into this 433 // scope. 434 while (S->getEntity() && 435 ((DeclContext *)S->getEntity())->isTransparentContext()) 436 S = S->getParent(); 437 438 // Add scoped declarations into their context, so that they can be 439 // found later. Declarations without a context won't be inserted 440 // into any context. 441 if (AddToContext) 442 CurContext->addDecl(D); 443 444 // Out-of-line function and variable definitions should not be pushed into 445 // scope. 446 if ((isa<FunctionTemplateDecl>(D) && 447 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 448 (isa<FunctionDecl>(D) && 449 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 450 cast<FunctionDecl>(D)->isOutOfLine())) || 451 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 452 return; 453 454 // If this replaces anything in the current scope, 455 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 456 IEnd = IdResolver.end(); 457 for (; I != IEnd; ++I) { 458 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 459 S->RemoveDecl(DeclPtrTy::make(*I)); 460 IdResolver.RemoveDecl(*I); 461 462 // Should only need to replace one decl. 463 break; 464 } 465 } 466 467 S->AddDecl(DeclPtrTy::make(D)); 468 IdResolver.AddDecl(D); 469} 470 471bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 472 return IdResolver.isDeclInScope(D, Ctx, Context, S); 473} 474 475static bool isOutOfScopePreviousDeclaration(NamedDecl *, 476 DeclContext*, 477 ASTContext&); 478 479/// Filters out lookup results that don't fall within the given scope 480/// as determined by isDeclInScope. 481static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 482 DeclContext *Ctx, Scope *S, 483 bool ConsiderLinkage) { 484 LookupResult::Filter F = R.makeFilter(); 485 while (F.hasNext()) { 486 NamedDecl *D = F.next(); 487 488 if (SemaRef.isDeclInScope(D, Ctx, S)) 489 continue; 490 491 if (ConsiderLinkage && 492 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 493 continue; 494 495 F.erase(); 496 } 497 498 F.done(); 499} 500 501static bool isUsingDecl(NamedDecl *D) { 502 return isa<UsingShadowDecl>(D) || 503 isa<UnresolvedUsingTypenameDecl>(D) || 504 isa<UnresolvedUsingValueDecl>(D); 505} 506 507/// Removes using shadow declarations from the lookup results. 508static void RemoveUsingDecls(LookupResult &R) { 509 LookupResult::Filter F = R.makeFilter(); 510 while (F.hasNext()) 511 if (isUsingDecl(F.next())) 512 F.erase(); 513 514 F.done(); 515} 516 517static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 518 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 519 return false; 520 521 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 522 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 523 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 524 if (!RD->hasTrivialConstructor()) 525 return false; 526 if (!RD->hasTrivialDestructor()) 527 return false; 528 } 529 } 530 } 531 532 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 533 !isa<ImplicitParamDecl>(D) && 534 D->getDeclContext()->isFunctionOrMethod()); 535} 536 537void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 538 if (S->decl_empty()) return; 539 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 540 "Scope shouldn't contain decls!"); 541 542 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 543 I != E; ++I) { 544 Decl *TmpD = (*I).getAs<Decl>(); 545 assert(TmpD && "This decl didn't get pushed??"); 546 547 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 548 NamedDecl *D = cast<NamedDecl>(TmpD); 549 550 if (!D->getDeclName()) continue; 551 552 // Diagnose unused variables in this scope. 553 if (ShouldDiagnoseUnusedDecl(D)) 554 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 555 556 // Remove this name from our lexical scope. 557 IdResolver.RemoveDecl(D); 558 } 559} 560 561/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 562/// return 0 if one not found. 563/// 564/// \param Id the name of the Objective-C class we're looking for. If 565/// typo-correction fixes this name, the Id will be updated 566/// to the fixed name. 567/// 568/// \param RecoverLoc if provided, this routine will attempt to 569/// recover from a typo in the name of an existing Objective-C class 570/// and, if successful, will return the lookup that results from 571/// typo-correction. 572ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 573 SourceLocation RecoverLoc) { 574 // The third "scope" argument is 0 since we aren't enabling lazy built-in 575 // creation from this context. 576 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 577 578 if (!IDecl && !RecoverLoc.isInvalid()) { 579 // Perform typo correction at the given location, but only if we 580 // find an Objective-C class name. 581 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 582 if (CorrectTypo(R, TUScope, 0) && 583 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 584 Diag(RecoverLoc, diag::err_undef_interface_suggest) 585 << Id << IDecl->getDeclName() 586 << CodeModificationHint::CreateReplacement(RecoverLoc, 587 IDecl->getNameAsString()); 588 Diag(IDecl->getLocation(), diag::note_previous_decl) 589 << IDecl->getDeclName(); 590 591 Id = IDecl->getIdentifier(); 592 } 593 } 594 595 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 596} 597 598/// getNonFieldDeclScope - Retrieves the innermost scope, starting 599/// from S, where a non-field would be declared. This routine copes 600/// with the difference between C and C++ scoping rules in structs and 601/// unions. For example, the following code is well-formed in C but 602/// ill-formed in C++: 603/// @code 604/// struct S6 { 605/// enum { BAR } e; 606/// }; 607/// 608/// void test_S6() { 609/// struct S6 a; 610/// a.e = BAR; 611/// } 612/// @endcode 613/// For the declaration of BAR, this routine will return a different 614/// scope. The scope S will be the scope of the unnamed enumeration 615/// within S6. In C++, this routine will return the scope associated 616/// with S6, because the enumeration's scope is a transparent 617/// context but structures can contain non-field names. In C, this 618/// routine will return the translation unit scope, since the 619/// enumeration's scope is a transparent context and structures cannot 620/// contain non-field names. 621Scope *Sema::getNonFieldDeclScope(Scope *S) { 622 while (((S->getFlags() & Scope::DeclScope) == 0) || 623 (S->getEntity() && 624 ((DeclContext *)S->getEntity())->isTransparentContext()) || 625 (S->isClassScope() && !getLangOptions().CPlusPlus)) 626 S = S->getParent(); 627 return S; 628} 629 630void Sema::InitBuiltinVaListType() { 631 if (!Context.getBuiltinVaListType().isNull()) 632 return; 633 634 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 635 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 636 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 637 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 638} 639 640/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 641/// file scope. lazily create a decl for it. ForRedeclaration is true 642/// if we're creating this built-in in anticipation of redeclaring the 643/// built-in. 644NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 645 Scope *S, bool ForRedeclaration, 646 SourceLocation Loc) { 647 Builtin::ID BID = (Builtin::ID)bid; 648 649 if (Context.BuiltinInfo.hasVAListUse(BID)) 650 InitBuiltinVaListType(); 651 652 ASTContext::GetBuiltinTypeError Error; 653 QualType R = Context.GetBuiltinType(BID, Error); 654 switch (Error) { 655 case ASTContext::GE_None: 656 // Okay 657 break; 658 659 case ASTContext::GE_Missing_stdio: 660 if (ForRedeclaration) 661 Diag(Loc, diag::err_implicit_decl_requires_stdio) 662 << Context.BuiltinInfo.GetName(BID); 663 return 0; 664 665 case ASTContext::GE_Missing_setjmp: 666 if (ForRedeclaration) 667 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 668 << Context.BuiltinInfo.GetName(BID); 669 return 0; 670 } 671 672 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 673 Diag(Loc, diag::ext_implicit_lib_function_decl) 674 << Context.BuiltinInfo.GetName(BID) 675 << R; 676 if (Context.BuiltinInfo.getHeaderName(BID) && 677 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 678 != Diagnostic::Ignored) 679 Diag(Loc, diag::note_please_include_header) 680 << Context.BuiltinInfo.getHeaderName(BID) 681 << Context.BuiltinInfo.GetName(BID); 682 } 683 684 FunctionDecl *New = FunctionDecl::Create(Context, 685 Context.getTranslationUnitDecl(), 686 Loc, II, R, /*TInfo=*/0, 687 FunctionDecl::Extern, false, 688 /*hasPrototype=*/true); 689 New->setImplicit(); 690 691 // Create Decl objects for each parameter, adding them to the 692 // FunctionDecl. 693 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 694 llvm::SmallVector<ParmVarDecl*, 16> Params; 695 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 696 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 697 FT->getArgType(i), /*TInfo=*/0, 698 VarDecl::None, 0)); 699 New->setParams(Context, Params.data(), Params.size()); 700 } 701 702 AddKnownFunctionAttributes(New); 703 704 // TUScope is the translation-unit scope to insert this function into. 705 // FIXME: This is hideous. We need to teach PushOnScopeChains to 706 // relate Scopes to DeclContexts, and probably eliminate CurContext 707 // entirely, but we're not there yet. 708 DeclContext *SavedContext = CurContext; 709 CurContext = Context.getTranslationUnitDecl(); 710 PushOnScopeChains(New, TUScope); 711 CurContext = SavedContext; 712 return New; 713} 714 715/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 716/// same name and scope as a previous declaration 'Old'. Figure out 717/// how to resolve this situation, merging decls or emitting 718/// diagnostics as appropriate. If there was an error, set New to be invalid. 719/// 720void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 721 // If the new decl is known invalid already, don't bother doing any 722 // merging checks. 723 if (New->isInvalidDecl()) return; 724 725 // Allow multiple definitions for ObjC built-in typedefs. 726 // FIXME: Verify the underlying types are equivalent! 727 if (getLangOptions().ObjC1) { 728 const IdentifierInfo *TypeID = New->getIdentifier(); 729 switch (TypeID->getLength()) { 730 default: break; 731 case 2: 732 if (!TypeID->isStr("id")) 733 break; 734 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 735 // Install the built-in type for 'id', ignoring the current definition. 736 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 737 return; 738 case 5: 739 if (!TypeID->isStr("Class")) 740 break; 741 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 742 // Install the built-in type for 'Class', ignoring the current definition. 743 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 744 return; 745 case 3: 746 if (!TypeID->isStr("SEL")) 747 break; 748 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 749 // Install the built-in type for 'SEL', ignoring the current definition. 750 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 751 return; 752 case 8: 753 if (!TypeID->isStr("Protocol")) 754 break; 755 Context.setObjCProtoType(New->getUnderlyingType()); 756 return; 757 } 758 // Fall through - the typedef name was not a builtin type. 759 } 760 761 // Verify the old decl was also a type. 762 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 763 if (!Old) { 764 Diag(New->getLocation(), diag::err_redefinition_different_kind) 765 << New->getDeclName(); 766 767 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 768 if (OldD->getLocation().isValid()) 769 Diag(OldD->getLocation(), diag::note_previous_definition); 770 771 return New->setInvalidDecl(); 772 } 773 774 // If the old declaration is invalid, just give up here. 775 if (Old->isInvalidDecl()) 776 return New->setInvalidDecl(); 777 778 // Determine the "old" type we'll use for checking and diagnostics. 779 QualType OldType; 780 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 781 OldType = OldTypedef->getUnderlyingType(); 782 else 783 OldType = Context.getTypeDeclType(Old); 784 785 // If the typedef types are not identical, reject them in all languages and 786 // with any extensions enabled. 787 788 if (OldType != New->getUnderlyingType() && 789 Context.getCanonicalType(OldType) != 790 Context.getCanonicalType(New->getUnderlyingType())) { 791 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 792 << New->getUnderlyingType() << OldType; 793 if (Old->getLocation().isValid()) 794 Diag(Old->getLocation(), diag::note_previous_definition); 795 return New->setInvalidDecl(); 796 } 797 798 // The types match. Link up the redeclaration chain if the old 799 // declaration was a typedef. 800 // FIXME: this is a potential source of wierdness if the type 801 // spellings don't match exactly. 802 if (isa<TypedefDecl>(Old)) 803 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 804 805 if (getLangOptions().Microsoft) 806 return; 807 808 if (getLangOptions().CPlusPlus) { 809 // C++ [dcl.typedef]p2: 810 // In a given non-class scope, a typedef specifier can be used to 811 // redefine the name of any type declared in that scope to refer 812 // to the type to which it already refers. 813 if (!isa<CXXRecordDecl>(CurContext)) 814 return; 815 816 // C++0x [dcl.typedef]p4: 817 // In a given class scope, a typedef specifier can be used to redefine 818 // any class-name declared in that scope that is not also a typedef-name 819 // to refer to the type to which it already refers. 820 // 821 // This wording came in via DR424, which was a correction to the 822 // wording in DR56, which accidentally banned code like: 823 // 824 // struct S { 825 // typedef struct A { } A; 826 // }; 827 // 828 // in the C++03 standard. We implement the C++0x semantics, which 829 // allow the above but disallow 830 // 831 // struct S { 832 // typedef int I; 833 // typedef int I; 834 // }; 835 // 836 // since that was the intent of DR56. 837 if (!isa<TypedefDecl >(Old)) 838 return; 839 840 Diag(New->getLocation(), diag::err_redefinition) 841 << New->getDeclName(); 842 Diag(Old->getLocation(), diag::note_previous_definition); 843 return New->setInvalidDecl(); 844 } 845 846 // If we have a redefinition of a typedef in C, emit a warning. This warning 847 // is normally mapped to an error, but can be controlled with 848 // -Wtypedef-redefinition. If either the original or the redefinition is 849 // in a system header, don't emit this for compatibility with GCC. 850 if (PP.getDiagnostics().getSuppressSystemWarnings() && 851 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 852 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 853 return; 854 855 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 856 << New->getDeclName(); 857 Diag(Old->getLocation(), diag::note_previous_definition); 858 return; 859} 860 861/// DeclhasAttr - returns true if decl Declaration already has the target 862/// attribute. 863static bool 864DeclHasAttr(const Decl *decl, const Attr *target) { 865 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 866 if (attr->getKind() == target->getKind()) 867 return true; 868 869 return false; 870} 871 872/// MergeAttributes - append attributes from the Old decl to the New one. 873static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 874 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 875 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 876 Attr *NewAttr = attr->clone(C); 877 NewAttr->setInherited(true); 878 New->addAttr(NewAttr); 879 } 880 } 881} 882 883/// Used in MergeFunctionDecl to keep track of function parameters in 884/// C. 885struct GNUCompatibleParamWarning { 886 ParmVarDecl *OldParm; 887 ParmVarDecl *NewParm; 888 QualType PromotedType; 889}; 890 891 892/// getSpecialMember - get the special member enum for a method. 893static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 894 const CXXMethodDecl *MD) { 895 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 896 if (Ctor->isDefaultConstructor()) 897 return Sema::CXXDefaultConstructor; 898 if (Ctor->isCopyConstructor()) 899 return Sema::CXXCopyConstructor; 900 } 901 902 if (isa<CXXDestructorDecl>(MD)) 903 return Sema::CXXDestructor; 904 905 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 906 return Sema::CXXCopyAssignment; 907} 908 909/// MergeFunctionDecl - We just parsed a function 'New' from 910/// declarator D which has the same name and scope as a previous 911/// declaration 'Old'. Figure out how to resolve this situation, 912/// merging decls or emitting diagnostics as appropriate. 913/// 914/// In C++, New and Old must be declarations that are not 915/// overloaded. Use IsOverload to determine whether New and Old are 916/// overloaded, and to select the Old declaration that New should be 917/// merged with. 918/// 919/// Returns true if there was an error, false otherwise. 920bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 921 // Verify the old decl was also a function. 922 FunctionDecl *Old = 0; 923 if (FunctionTemplateDecl *OldFunctionTemplate 924 = dyn_cast<FunctionTemplateDecl>(OldD)) 925 Old = OldFunctionTemplate->getTemplatedDecl(); 926 else 927 Old = dyn_cast<FunctionDecl>(OldD); 928 if (!Old) { 929 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 930 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 931 Diag(Shadow->getTargetDecl()->getLocation(), 932 diag::note_using_decl_target); 933 Diag(Shadow->getUsingDecl()->getLocation(), 934 diag::note_using_decl) << 0; 935 return true; 936 } 937 938 Diag(New->getLocation(), diag::err_redefinition_different_kind) 939 << New->getDeclName(); 940 Diag(OldD->getLocation(), diag::note_previous_definition); 941 return true; 942 } 943 944 // Determine whether the previous declaration was a definition, 945 // implicit declaration, or a declaration. 946 diag::kind PrevDiag; 947 if (Old->isThisDeclarationADefinition()) 948 PrevDiag = diag::note_previous_definition; 949 else if (Old->isImplicit()) 950 PrevDiag = diag::note_previous_implicit_declaration; 951 else 952 PrevDiag = diag::note_previous_declaration; 953 954 QualType OldQType = Context.getCanonicalType(Old->getType()); 955 QualType NewQType = Context.getCanonicalType(New->getType()); 956 957 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 958 New->getStorageClass() == FunctionDecl::Static && 959 Old->getStorageClass() != FunctionDecl::Static) { 960 Diag(New->getLocation(), diag::err_static_non_static) 961 << New; 962 Diag(Old->getLocation(), PrevDiag); 963 return true; 964 } 965 966 if (getLangOptions().CPlusPlus) { 967 // (C++98 13.1p2): 968 // Certain function declarations cannot be overloaded: 969 // -- Function declarations that differ only in the return type 970 // cannot be overloaded. 971 QualType OldReturnType 972 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 973 QualType NewReturnType 974 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 975 if (OldReturnType != NewReturnType) { 976 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 977 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 978 return true; 979 } 980 981 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 982 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 983 if (OldMethod && NewMethod) { 984 if (!NewMethod->getFriendObjectKind() && 985 NewMethod->getLexicalDeclContext()->isRecord()) { 986 // -- Member function declarations with the same name and the 987 // same parameter types cannot be overloaded if any of them 988 // is a static member function declaration. 989 if (OldMethod->isStatic() || NewMethod->isStatic()) { 990 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 991 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 992 return true; 993 } 994 995 // C++ [class.mem]p1: 996 // [...] A member shall not be declared twice in the 997 // member-specification, except that a nested class or member 998 // class template can be declared and then later defined. 999 unsigned NewDiag; 1000 if (isa<CXXConstructorDecl>(OldMethod)) 1001 NewDiag = diag::err_constructor_redeclared; 1002 else if (isa<CXXDestructorDecl>(NewMethod)) 1003 NewDiag = diag::err_destructor_redeclared; 1004 else if (isa<CXXConversionDecl>(NewMethod)) 1005 NewDiag = diag::err_conv_function_redeclared; 1006 else 1007 NewDiag = diag::err_member_redeclared; 1008 1009 Diag(New->getLocation(), NewDiag); 1010 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1011 } else { 1012 if (OldMethod->isImplicit()) { 1013 Diag(NewMethod->getLocation(), 1014 diag::err_definition_of_implicitly_declared_member) 1015 << New << getSpecialMember(Context, OldMethod); 1016 1017 Diag(OldMethod->getLocation(), 1018 diag::note_previous_implicit_declaration); 1019 return true; 1020 } 1021 } 1022 } 1023 1024 // (C++98 8.3.5p3): 1025 // All declarations for a function shall agree exactly in both the 1026 // return type and the parameter-type-list. 1027 // attributes should be ignored when comparing. 1028 if (Context.getNoReturnType(OldQType, false) == 1029 Context.getNoReturnType(NewQType, false)) 1030 return MergeCompatibleFunctionDecls(New, Old); 1031 1032 // Fall through for conflicting redeclarations and redefinitions. 1033 } 1034 1035 // C: Function types need to be compatible, not identical. This handles 1036 // duplicate function decls like "void f(int); void f(enum X);" properly. 1037 if (!getLangOptions().CPlusPlus && 1038 Context.typesAreCompatible(OldQType, NewQType)) { 1039 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1040 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1041 const FunctionProtoType *OldProto = 0; 1042 if (isa<FunctionNoProtoType>(NewFuncType) && 1043 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1044 // The old declaration provided a function prototype, but the 1045 // new declaration does not. Merge in the prototype. 1046 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1047 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1048 OldProto->arg_type_end()); 1049 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1050 ParamTypes.data(), ParamTypes.size(), 1051 OldProto->isVariadic(), 1052 OldProto->getTypeQuals()); 1053 New->setType(NewQType); 1054 New->setHasInheritedPrototype(); 1055 1056 // Synthesize a parameter for each argument type. 1057 llvm::SmallVector<ParmVarDecl*, 16> Params; 1058 for (FunctionProtoType::arg_type_iterator 1059 ParamType = OldProto->arg_type_begin(), 1060 ParamEnd = OldProto->arg_type_end(); 1061 ParamType != ParamEnd; ++ParamType) { 1062 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1063 SourceLocation(), 0, 1064 *ParamType, /*TInfo=*/0, 1065 VarDecl::None, 0); 1066 Param->setImplicit(); 1067 Params.push_back(Param); 1068 } 1069 1070 New->setParams(Context, Params.data(), Params.size()); 1071 } 1072 1073 return MergeCompatibleFunctionDecls(New, Old); 1074 } 1075 1076 // GNU C permits a K&R definition to follow a prototype declaration 1077 // if the declared types of the parameters in the K&R definition 1078 // match the types in the prototype declaration, even when the 1079 // promoted types of the parameters from the K&R definition differ 1080 // from the types in the prototype. GCC then keeps the types from 1081 // the prototype. 1082 // 1083 // If a variadic prototype is followed by a non-variadic K&R definition, 1084 // the K&R definition becomes variadic. This is sort of an edge case, but 1085 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1086 // C99 6.9.1p8. 1087 if (!getLangOptions().CPlusPlus && 1088 Old->hasPrototype() && !New->hasPrototype() && 1089 New->getType()->getAs<FunctionProtoType>() && 1090 Old->getNumParams() == New->getNumParams()) { 1091 llvm::SmallVector<QualType, 16> ArgTypes; 1092 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1093 const FunctionProtoType *OldProto 1094 = Old->getType()->getAs<FunctionProtoType>(); 1095 const FunctionProtoType *NewProto 1096 = New->getType()->getAs<FunctionProtoType>(); 1097 1098 // Determine whether this is the GNU C extension. 1099 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1100 NewProto->getResultType()); 1101 bool LooseCompatible = !MergedReturn.isNull(); 1102 for (unsigned Idx = 0, End = Old->getNumParams(); 1103 LooseCompatible && Idx != End; ++Idx) { 1104 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1105 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1106 if (Context.typesAreCompatible(OldParm->getType(), 1107 NewProto->getArgType(Idx))) { 1108 ArgTypes.push_back(NewParm->getType()); 1109 } else if (Context.typesAreCompatible(OldParm->getType(), 1110 NewParm->getType())) { 1111 GNUCompatibleParamWarning Warn 1112 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1113 Warnings.push_back(Warn); 1114 ArgTypes.push_back(NewParm->getType()); 1115 } else 1116 LooseCompatible = false; 1117 } 1118 1119 if (LooseCompatible) { 1120 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1121 Diag(Warnings[Warn].NewParm->getLocation(), 1122 diag::ext_param_promoted_not_compatible_with_prototype) 1123 << Warnings[Warn].PromotedType 1124 << Warnings[Warn].OldParm->getType(); 1125 Diag(Warnings[Warn].OldParm->getLocation(), 1126 diag::note_previous_declaration); 1127 } 1128 1129 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1130 ArgTypes.size(), 1131 OldProto->isVariadic(), 0)); 1132 return MergeCompatibleFunctionDecls(New, Old); 1133 } 1134 1135 // Fall through to diagnose conflicting types. 1136 } 1137 1138 // A function that has already been declared has been redeclared or defined 1139 // with a different type- show appropriate diagnostic 1140 if (unsigned BuiltinID = Old->getBuiltinID()) { 1141 // The user has declared a builtin function with an incompatible 1142 // signature. 1143 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1144 // The function the user is redeclaring is a library-defined 1145 // function like 'malloc' or 'printf'. Warn about the 1146 // redeclaration, then pretend that we don't know about this 1147 // library built-in. 1148 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1149 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1150 << Old << Old->getType(); 1151 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1152 Old->setInvalidDecl(); 1153 return false; 1154 } 1155 1156 PrevDiag = diag::note_previous_builtin_declaration; 1157 } 1158 1159 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1160 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1161 return true; 1162} 1163 1164/// \brief Completes the merge of two function declarations that are 1165/// known to be compatible. 1166/// 1167/// This routine handles the merging of attributes and other 1168/// properties of function declarations form the old declaration to 1169/// the new declaration, once we know that New is in fact a 1170/// redeclaration of Old. 1171/// 1172/// \returns false 1173bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1174 // Merge the attributes 1175 MergeAttributes(New, Old, Context); 1176 1177 // Merge the storage class. 1178 if (Old->getStorageClass() != FunctionDecl::Extern && 1179 Old->getStorageClass() != FunctionDecl::None) 1180 New->setStorageClass(Old->getStorageClass()); 1181 1182 // Merge "pure" flag. 1183 if (Old->isPure()) 1184 New->setPure(); 1185 1186 // Merge the "deleted" flag. 1187 if (Old->isDeleted()) 1188 New->setDeleted(); 1189 1190 if (getLangOptions().CPlusPlus) 1191 return MergeCXXFunctionDecl(New, Old); 1192 1193 return false; 1194} 1195 1196/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1197/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1198/// situation, merging decls or emitting diagnostics as appropriate. 1199/// 1200/// Tentative definition rules (C99 6.9.2p2) are checked by 1201/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1202/// definitions here, since the initializer hasn't been attached. 1203/// 1204void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1205 // If the new decl is already invalid, don't do any other checking. 1206 if (New->isInvalidDecl()) 1207 return; 1208 1209 // Verify the old decl was also a variable. 1210 VarDecl *Old = 0; 1211 if (!Previous.isSingleResult() || 1212 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1213 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1214 << New->getDeclName(); 1215 Diag(Previous.getRepresentativeDecl()->getLocation(), 1216 diag::note_previous_definition); 1217 return New->setInvalidDecl(); 1218 } 1219 1220 MergeAttributes(New, Old, Context); 1221 1222 // Merge the types 1223 QualType MergedT; 1224 if (getLangOptions().CPlusPlus) { 1225 if (Context.hasSameType(New->getType(), Old->getType())) 1226 MergedT = New->getType(); 1227 // C++ [basic.link]p10: 1228 // [...] the types specified by all declarations referring to a given 1229 // object or function shall be identical, except that declarations for an 1230 // array object can specify array types that differ by the presence or 1231 // absence of a major array bound (8.3.4). 1232 else if (Old->getType()->isIncompleteArrayType() && 1233 New->getType()->isArrayType()) { 1234 CanQual<ArrayType> OldArray 1235 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1236 CanQual<ArrayType> NewArray 1237 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1238 if (OldArray->getElementType() == NewArray->getElementType()) 1239 MergedT = New->getType(); 1240 } else if (Old->getType()->isArrayType() && 1241 New->getType()->isIncompleteArrayType()) { 1242 CanQual<ArrayType> OldArray 1243 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1244 CanQual<ArrayType> NewArray 1245 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1246 if (OldArray->getElementType() == NewArray->getElementType()) 1247 MergedT = Old->getType(); 1248 } 1249 } else { 1250 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1251 } 1252 if (MergedT.isNull()) { 1253 Diag(New->getLocation(), diag::err_redefinition_different_type) 1254 << New->getDeclName(); 1255 Diag(Old->getLocation(), diag::note_previous_definition); 1256 return New->setInvalidDecl(); 1257 } 1258 New->setType(MergedT); 1259 1260 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1261 if (New->getStorageClass() == VarDecl::Static && 1262 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1263 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1264 Diag(Old->getLocation(), diag::note_previous_definition); 1265 return New->setInvalidDecl(); 1266 } 1267 // C99 6.2.2p4: 1268 // For an identifier declared with the storage-class specifier 1269 // extern in a scope in which a prior declaration of that 1270 // identifier is visible,23) if the prior declaration specifies 1271 // internal or external linkage, the linkage of the identifier at 1272 // the later declaration is the same as the linkage specified at 1273 // the prior declaration. If no prior declaration is visible, or 1274 // if the prior declaration specifies no linkage, then the 1275 // identifier has external linkage. 1276 if (New->hasExternalStorage() && Old->hasLinkage()) 1277 /* Okay */; 1278 else if (New->getStorageClass() != VarDecl::Static && 1279 Old->getStorageClass() == VarDecl::Static) { 1280 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1281 Diag(Old->getLocation(), diag::note_previous_definition); 1282 return New->setInvalidDecl(); 1283 } 1284 1285 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1286 1287 // FIXME: The test for external storage here seems wrong? We still 1288 // need to check for mismatches. 1289 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1290 // Don't complain about out-of-line definitions of static members. 1291 !(Old->getLexicalDeclContext()->isRecord() && 1292 !New->getLexicalDeclContext()->isRecord())) { 1293 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1294 Diag(Old->getLocation(), diag::note_previous_definition); 1295 return New->setInvalidDecl(); 1296 } 1297 1298 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1299 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1300 Diag(Old->getLocation(), diag::note_previous_definition); 1301 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1302 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1303 Diag(Old->getLocation(), diag::note_previous_definition); 1304 } 1305 1306 // Keep a chain of previous declarations. 1307 New->setPreviousDeclaration(Old); 1308} 1309 1310static void MarkLive(CFGBlock *e, llvm::BitVector &live) { 1311 std::queue<CFGBlock*> workq; 1312 // Prep work queue 1313 workq.push(e); 1314 // Solve 1315 while (!workq.empty()) { 1316 CFGBlock *item = workq.front(); 1317 workq.pop(); 1318 live.set(item->getBlockID()); 1319 for (CFGBlock::succ_iterator I=item->succ_begin(), 1320 E=item->succ_end(); 1321 I != E; 1322 ++I) { 1323 if ((*I) && !live[(*I)->getBlockID()]) { 1324 live.set((*I)->getBlockID()); 1325 workq.push(*I); 1326 } 1327 } 1328 } 1329} 1330 1331static SourceLocation GetUnreachableLoc(CFGBlock &b) { 1332 Stmt *S; 1333 if (!b.empty()) 1334 S = b[0].getStmt(); 1335 else if (b.getTerminator()) 1336 S = b.getTerminator(); 1337 else 1338 return SourceLocation(); 1339 1340 switch (S->getStmtClass()) { 1341 case Expr::BinaryOperatorClass: { 1342 if (b.size() < 2) { 1343 CFGBlock *n = &b; 1344 while (1) { 1345 if (n->getTerminator()) 1346 return n->getTerminator()->getLocStart(); 1347 if (n->succ_size() != 1) 1348 return SourceLocation(); 1349 n = n[0].succ_begin()[0]; 1350 if (n->pred_size() != 1) 1351 return SourceLocation(); 1352 if (!n->empty()) 1353 return n[0][0].getStmt()->getLocStart(); 1354 } 1355 } 1356 return b[1].getStmt()->getLocStart(); 1357 } 1358 default: ; 1359 } 1360 return S->getLocStart(); 1361} 1362 1363static SourceLocation MarkLiveTop(CFGBlock *e, llvm::BitVector &live, 1364 SourceManager &SM) { 1365 std::queue<CFGBlock*> workq; 1366 // Prep work queue 1367 workq.push(e); 1368 SourceLocation top = GetUnreachableLoc(*e); 1369 bool FromMainFile = false; 1370 bool FromSystemHeader = false; 1371 bool TopValid = false; 1372 if (top.isValid()) { 1373 FromMainFile = SM.isFromMainFile(top); 1374 FromSystemHeader = SM.isInSystemHeader(top); 1375 TopValid = true; 1376 } 1377 // Solve 1378 while (!workq.empty()) { 1379 CFGBlock *item = workq.front(); 1380 workq.pop(); 1381 SourceLocation c = GetUnreachableLoc(*item); 1382 if (c.isValid() 1383 && (!TopValid 1384 || (SM.isFromMainFile(c) && !FromMainFile) 1385 || (FromSystemHeader && !SM.isInSystemHeader(c)) 1386 || SM.isBeforeInTranslationUnit(c, top))) { 1387 top = c; 1388 FromMainFile = SM.isFromMainFile(top); 1389 FromSystemHeader = SM.isInSystemHeader(top); 1390 } 1391 live.set(item->getBlockID()); 1392 for (CFGBlock::succ_iterator I=item->succ_begin(), 1393 E=item->succ_end(); 1394 I != E; 1395 ++I) { 1396 if ((*I) && !live[(*I)->getBlockID()]) { 1397 live.set((*I)->getBlockID()); 1398 workq.push(*I); 1399 } 1400 } 1401 } 1402 return top; 1403} 1404 1405namespace { 1406class LineCmp { 1407 SourceManager &SM; 1408public: 1409 LineCmp(SourceManager &sm) : SM(sm) { 1410 } 1411 bool operator () (SourceLocation l1, SourceLocation l2) { 1412 return l1 < l2; 1413 } 1414}; 1415} 1416 1417/// CheckUnreachable - Check for unreachable code. 1418void Sema::CheckUnreachable(AnalysisContext &AC) { 1419 // We avoid checking when there are errors, as the CFG won't faithfully match 1420 // the user's code. 1421 if (getDiagnostics().hasErrorOccurred()) 1422 return; 1423 if (Diags.getDiagnosticLevel(diag::warn_unreachable) == Diagnostic::Ignored) 1424 return; 1425 1426 CFG *cfg = AC.getCFG(); 1427 if (cfg == 0) 1428 return; 1429 1430 llvm::BitVector live(cfg->getNumBlockIDs()); 1431 // Mark all live things first. 1432 MarkLive(&cfg->getEntry(), live); 1433 1434 llvm::SmallVector<SourceLocation, 24> lines; 1435 // First, give warnings for blocks with no predecessors, as they 1436 // can't be part of a loop. 1437 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1438 CFGBlock &b = **I; 1439 if (!live[b.getBlockID()]) { 1440 if (b.pred_begin() == b.pred_end()) { 1441 SourceLocation c = GetUnreachableLoc(b); 1442 if (!c.isValid()) { 1443 // Blocks without a location can't produce a warning, so don't mark 1444 // reachable blocks from here as live. 1445 live.set(b.getBlockID()); 1446 continue; 1447 } 1448 lines.push_back(c); 1449 // Avoid excessive errors by marking everything reachable from here 1450 MarkLive(&b, live); 1451 } 1452 } 1453 } 1454 1455 // And then give warnings for the tops of loops. 1456 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1457 CFGBlock &b = **I; 1458 if (!live[b.getBlockID()]) 1459 // Avoid excessive errors by marking everything reachable from here 1460 lines.push_back(MarkLiveTop(&b, live, Context.getSourceManager())); 1461 } 1462 1463 std::sort(lines.begin(), lines.end(), LineCmp(Context.getSourceManager())); 1464 for (llvm::SmallVector<SourceLocation, 24>::iterator I = lines.begin(), 1465 E = lines.end(); 1466 I != E; 1467 ++I) 1468 if (I->isValid()) 1469 Diag(*I, diag::warn_unreachable); 1470} 1471 1472/// CheckFallThrough - Check that we don't fall off the end of a 1473/// Statement that should return a value. 1474/// 1475/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1476/// MaybeFallThrough iff we might or might not fall off the end, 1477/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1478/// return. We assume NeverFallThrough iff we never fall off the end of the 1479/// statement but we may return. We assume that functions not marked noreturn 1480/// will return. 1481Sema::ControlFlowKind Sema::CheckFallThrough(AnalysisContext &AC) { 1482 CFG *cfg = AC.getCFG(); 1483 if (cfg == 0) 1484 // FIXME: This should be NeverFallThrough 1485 return NeverFallThroughOrReturn; 1486 1487 // The CFG leaves in dead things, and we don't want to dead code paths to 1488 // confuse us, so we mark all live things first. 1489 std::queue<CFGBlock*> workq; 1490 llvm::BitVector live(cfg->getNumBlockIDs()); 1491 MarkLive(&cfg->getEntry(), live); 1492 1493 // Now we know what is live, we check the live precessors of the exit block 1494 // and look for fall through paths, being careful to ignore normal returns, 1495 // and exceptional paths. 1496 bool HasLiveReturn = false; 1497 bool HasFakeEdge = false; 1498 bool HasPlainEdge = false; 1499 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1500 E = cfg->getExit().pred_end(); 1501 I != E; 1502 ++I) { 1503 CFGBlock& B = **I; 1504 if (!live[B.getBlockID()]) 1505 continue; 1506 if (B.size() == 0) { 1507 // A labeled empty statement, or the entry block... 1508 HasPlainEdge = true; 1509 continue; 1510 } 1511 Stmt *S = B[B.size()-1]; 1512 if (isa<ReturnStmt>(S)) { 1513 HasLiveReturn = true; 1514 continue; 1515 } 1516 if (isa<ObjCAtThrowStmt>(S)) { 1517 HasFakeEdge = true; 1518 continue; 1519 } 1520 if (isa<CXXThrowExpr>(S)) { 1521 HasFakeEdge = true; 1522 continue; 1523 } 1524 if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) { 1525 if (AS->isMSAsm()) { 1526 HasFakeEdge = true; 1527 HasLiveReturn = true; 1528 continue; 1529 } 1530 } 1531 1532 bool NoReturnEdge = false; 1533 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1534 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1535 if (CEE->getType().getNoReturnAttr()) { 1536 NoReturnEdge = true; 1537 HasFakeEdge = true; 1538 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1539 ValueDecl *VD = DRE->getDecl(); 1540 if (VD->hasAttr<NoReturnAttr>()) { 1541 NoReturnEdge = true; 1542 HasFakeEdge = true; 1543 } 1544 } 1545 } 1546 // FIXME: Add noreturn message sends. 1547 if (NoReturnEdge == false) 1548 HasPlainEdge = true; 1549 } 1550 if (!HasPlainEdge) { 1551 if (HasLiveReturn) 1552 return NeverFallThrough; 1553 return NeverFallThroughOrReturn; 1554 } 1555 if (HasFakeEdge || HasLiveReturn) 1556 return MaybeFallThrough; 1557 // This says AlwaysFallThrough for calls to functions that are not marked 1558 // noreturn, that don't return. If people would like this warning to be more 1559 // accurate, such functions should be marked as noreturn. 1560 return AlwaysFallThrough; 1561} 1562 1563/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1564/// function that should return a value. Check that we don't fall off the end 1565/// of a noreturn function. We assume that functions and blocks not marked 1566/// noreturn will return. 1567void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body, 1568 AnalysisContext &AC) { 1569 // FIXME: Would be nice if we had a better way to control cascading errors, 1570 // but for now, avoid them. The problem is that when Parse sees: 1571 // int foo() { return a; } 1572 // The return is eaten and the Sema code sees just: 1573 // int foo() { } 1574 // which this code would then warn about. 1575 if (getDiagnostics().hasErrorOccurred()) 1576 return; 1577 1578 bool ReturnsVoid = false; 1579 bool HasNoReturn = false; 1580 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1581 // If the result type of the function is a dependent type, we don't know 1582 // whether it will be void or not, so don't 1583 if (FD->getResultType()->isDependentType()) 1584 return; 1585 if (FD->getResultType()->isVoidType()) 1586 ReturnsVoid = true; 1587 if (FD->hasAttr<NoReturnAttr>()) 1588 HasNoReturn = true; 1589 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1590 if (MD->getResultType()->isVoidType()) 1591 ReturnsVoid = true; 1592 if (MD->hasAttr<NoReturnAttr>()) 1593 HasNoReturn = true; 1594 } 1595 1596 // Short circuit for compilation speed. 1597 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1598 == Diagnostic::Ignored || ReturnsVoid) 1599 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1600 == Diagnostic::Ignored || !HasNoReturn) 1601 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1602 == Diagnostic::Ignored || !ReturnsVoid)) 1603 return; 1604 // FIXME: Function try block 1605 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1606 switch (CheckFallThrough(AC)) { 1607 case MaybeFallThrough: 1608 if (HasNoReturn) 1609 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1610 else if (!ReturnsVoid) 1611 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1612 break; 1613 case AlwaysFallThrough: 1614 if (HasNoReturn) 1615 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1616 else if (!ReturnsVoid) 1617 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1618 break; 1619 case NeverFallThroughOrReturn: 1620 if (ReturnsVoid && !HasNoReturn) 1621 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1622 break; 1623 case NeverFallThrough: 1624 break; 1625 } 1626 } 1627} 1628 1629/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1630/// that should return a value. Check that we don't fall off the end of a 1631/// noreturn block. We assume that functions and blocks not marked noreturn 1632/// will return. 1633void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body, 1634 AnalysisContext &AC) { 1635 // FIXME: Would be nice if we had a better way to control cascading errors, 1636 // but for now, avoid them. The problem is that when Parse sees: 1637 // int foo() { return a; } 1638 // The return is eaten and the Sema code sees just: 1639 // int foo() { } 1640 // which this code would then warn about. 1641 if (getDiagnostics().hasErrorOccurred()) 1642 return; 1643 bool ReturnsVoid = false; 1644 bool HasNoReturn = false; 1645 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1646 if (FT->getResultType()->isVoidType()) 1647 ReturnsVoid = true; 1648 if (FT->getNoReturnAttr()) 1649 HasNoReturn = true; 1650 } 1651 1652 // Short circuit for compilation speed. 1653 if (ReturnsVoid 1654 && !HasNoReturn 1655 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1656 == Diagnostic::Ignored || !ReturnsVoid)) 1657 return; 1658 // FIXME: Funtion try block 1659 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1660 switch (CheckFallThrough(AC)) { 1661 case MaybeFallThrough: 1662 if (HasNoReturn) 1663 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1664 else if (!ReturnsVoid) 1665 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1666 break; 1667 case AlwaysFallThrough: 1668 if (HasNoReturn) 1669 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1670 else if (!ReturnsVoid) 1671 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1672 break; 1673 case NeverFallThroughOrReturn: 1674 if (ReturnsVoid) 1675 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1676 break; 1677 case NeverFallThrough: 1678 break; 1679 } 1680 } 1681} 1682 1683/// CheckParmsForFunctionDef - Check that the parameters of the given 1684/// function are appropriate for the definition of a function. This 1685/// takes care of any checks that cannot be performed on the 1686/// declaration itself, e.g., that the types of each of the function 1687/// parameters are complete. 1688bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1689 bool HasInvalidParm = false; 1690 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1691 ParmVarDecl *Param = FD->getParamDecl(p); 1692 1693 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1694 // function declarator that is part of a function definition of 1695 // that function shall not have incomplete type. 1696 // 1697 // This is also C++ [dcl.fct]p6. 1698 if (!Param->isInvalidDecl() && 1699 RequireCompleteType(Param->getLocation(), Param->getType(), 1700 diag::err_typecheck_decl_incomplete_type)) { 1701 Param->setInvalidDecl(); 1702 HasInvalidParm = true; 1703 } 1704 1705 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1706 // declaration of each parameter shall include an identifier. 1707 if (Param->getIdentifier() == 0 && 1708 !Param->isImplicit() && 1709 !getLangOptions().CPlusPlus) 1710 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1711 } 1712 1713 return HasInvalidParm; 1714} 1715 1716/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1717/// no declarator (e.g. "struct foo;") is parsed. 1718Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1719 // FIXME: Error on auto/register at file scope 1720 // FIXME: Error on inline/virtual/explicit 1721 // FIXME: Warn on useless __thread 1722 // FIXME: Warn on useless const/volatile 1723 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1724 // FIXME: Warn on useless attributes 1725 Decl *TagD = 0; 1726 TagDecl *Tag = 0; 1727 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1728 DS.getTypeSpecType() == DeclSpec::TST_struct || 1729 DS.getTypeSpecType() == DeclSpec::TST_union || 1730 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1731 TagD = static_cast<Decl *>(DS.getTypeRep()); 1732 1733 if (!TagD) // We probably had an error 1734 return DeclPtrTy(); 1735 1736 // Note that the above type specs guarantee that the 1737 // type rep is a Decl, whereas in many of the others 1738 // it's a Type. 1739 Tag = dyn_cast<TagDecl>(TagD); 1740 } 1741 1742 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1743 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1744 // or incomplete types shall not be restrict-qualified." 1745 if (TypeQuals & DeclSpec::TQ_restrict) 1746 Diag(DS.getRestrictSpecLoc(), 1747 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1748 << DS.getSourceRange(); 1749 } 1750 1751 if (DS.isFriendSpecified()) { 1752 // If we're dealing with a class template decl, assume that the 1753 // template routines are handling it. 1754 if (TagD && isa<ClassTemplateDecl>(TagD)) 1755 return DeclPtrTy(); 1756 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1757 } 1758 1759 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1760 // If there are attributes in the DeclSpec, apply them to the record. 1761 if (const AttributeList *AL = DS.getAttributes()) 1762 ProcessDeclAttributeList(S, Record, AL); 1763 1764 if (!Record->getDeclName() && Record->isDefinition() && 1765 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1766 if (getLangOptions().CPlusPlus || 1767 Record->getDeclContext()->isRecord()) 1768 return BuildAnonymousStructOrUnion(S, DS, Record); 1769 1770 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1771 << DS.getSourceRange(); 1772 } 1773 1774 // Microsoft allows unnamed struct/union fields. Don't complain 1775 // about them. 1776 // FIXME: Should we support Microsoft's extensions in this area? 1777 if (Record->getDeclName() && getLangOptions().Microsoft) 1778 return DeclPtrTy::make(Tag); 1779 } 1780 1781 if (!DS.isMissingDeclaratorOk() && 1782 DS.getTypeSpecType() != DeclSpec::TST_error) { 1783 // Warn about typedefs of enums without names, since this is an 1784 // extension in both Microsoft an GNU. 1785 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1786 Tag && isa<EnumDecl>(Tag)) { 1787 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1788 << DS.getSourceRange(); 1789 return DeclPtrTy::make(Tag); 1790 } 1791 1792 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1793 << DS.getSourceRange(); 1794 return DeclPtrTy(); 1795 } 1796 1797 return DeclPtrTy::make(Tag); 1798} 1799 1800/// We are trying to inject an anonymous member into the given scope; 1801/// check if there's an existing declaration that can't be overloaded. 1802/// 1803/// \return true if this is a forbidden redeclaration 1804static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1805 Scope *S, 1806 DeclarationName Name, 1807 SourceLocation NameLoc, 1808 unsigned diagnostic) { 1809 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1810 Sema::ForRedeclaration); 1811 if (!SemaRef.LookupName(R, S)) return false; 1812 1813 if (R.getAsSingle<TagDecl>()) 1814 return false; 1815 1816 // Pick a representative declaration. 1817 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1818 1819 SemaRef.Diag(NameLoc, diagnostic) << Name; 1820 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1821 1822 return true; 1823} 1824 1825/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1826/// anonymous struct or union AnonRecord into the owning context Owner 1827/// and scope S. This routine will be invoked just after we realize 1828/// that an unnamed union or struct is actually an anonymous union or 1829/// struct, e.g., 1830/// 1831/// @code 1832/// union { 1833/// int i; 1834/// float f; 1835/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1836/// // f into the surrounding scope.x 1837/// @endcode 1838/// 1839/// This routine is recursive, injecting the names of nested anonymous 1840/// structs/unions into the owning context and scope as well. 1841bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1842 RecordDecl *AnonRecord) { 1843 unsigned diagKind 1844 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1845 : diag::err_anonymous_struct_member_redecl; 1846 1847 bool Invalid = false; 1848 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1849 FEnd = AnonRecord->field_end(); 1850 F != FEnd; ++F) { 1851 if ((*F)->getDeclName()) { 1852 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1853 (*F)->getLocation(), diagKind)) { 1854 // C++ [class.union]p2: 1855 // The names of the members of an anonymous union shall be 1856 // distinct from the names of any other entity in the 1857 // scope in which the anonymous union is declared. 1858 Invalid = true; 1859 } else { 1860 // C++ [class.union]p2: 1861 // For the purpose of name lookup, after the anonymous union 1862 // definition, the members of the anonymous union are 1863 // considered to have been defined in the scope in which the 1864 // anonymous union is declared. 1865 Owner->makeDeclVisibleInContext(*F); 1866 S->AddDecl(DeclPtrTy::make(*F)); 1867 IdResolver.AddDecl(*F); 1868 } 1869 } else if (const RecordType *InnerRecordType 1870 = (*F)->getType()->getAs<RecordType>()) { 1871 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1872 if (InnerRecord->isAnonymousStructOrUnion()) 1873 Invalid = Invalid || 1874 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1875 } 1876 } 1877 1878 return Invalid; 1879} 1880 1881/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1882/// anonymous structure or union. Anonymous unions are a C++ feature 1883/// (C++ [class.union]) and a GNU C extension; anonymous structures 1884/// are a GNU C and GNU C++ extension. 1885Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1886 RecordDecl *Record) { 1887 DeclContext *Owner = Record->getDeclContext(); 1888 1889 // Diagnose whether this anonymous struct/union is an extension. 1890 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1891 Diag(Record->getLocation(), diag::ext_anonymous_union); 1892 else if (!Record->isUnion()) 1893 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1894 1895 // C and C++ require different kinds of checks for anonymous 1896 // structs/unions. 1897 bool Invalid = false; 1898 if (getLangOptions().CPlusPlus) { 1899 const char* PrevSpec = 0; 1900 unsigned DiagID; 1901 // C++ [class.union]p3: 1902 // Anonymous unions declared in a named namespace or in the 1903 // global namespace shall be declared static. 1904 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1905 (isa<TranslationUnitDecl>(Owner) || 1906 (isa<NamespaceDecl>(Owner) && 1907 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1908 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1909 Invalid = true; 1910 1911 // Recover by adding 'static'. 1912 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1913 PrevSpec, DiagID); 1914 } 1915 // C++ [class.union]p3: 1916 // A storage class is not allowed in a declaration of an 1917 // anonymous union in a class scope. 1918 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1919 isa<RecordDecl>(Owner)) { 1920 Diag(DS.getStorageClassSpecLoc(), 1921 diag::err_anonymous_union_with_storage_spec); 1922 Invalid = true; 1923 1924 // Recover by removing the storage specifier. 1925 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1926 PrevSpec, DiagID); 1927 } 1928 1929 // C++ [class.union]p2: 1930 // The member-specification of an anonymous union shall only 1931 // define non-static data members. [Note: nested types and 1932 // functions cannot be declared within an anonymous union. ] 1933 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1934 MemEnd = Record->decls_end(); 1935 Mem != MemEnd; ++Mem) { 1936 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1937 // C++ [class.union]p3: 1938 // An anonymous union shall not have private or protected 1939 // members (clause 11). 1940 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1941 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1942 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1943 Invalid = true; 1944 } 1945 } else if ((*Mem)->isImplicit()) { 1946 // Any implicit members are fine. 1947 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1948 // This is a type that showed up in an 1949 // elaborated-type-specifier inside the anonymous struct or 1950 // union, but which actually declares a type outside of the 1951 // anonymous struct or union. It's okay. 1952 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1953 if (!MemRecord->isAnonymousStructOrUnion() && 1954 MemRecord->getDeclName()) { 1955 // This is a nested type declaration. 1956 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1957 << (int)Record->isUnion(); 1958 Invalid = true; 1959 } 1960 } else { 1961 // We have something that isn't a non-static data 1962 // member. Complain about it. 1963 unsigned DK = diag::err_anonymous_record_bad_member; 1964 if (isa<TypeDecl>(*Mem)) 1965 DK = diag::err_anonymous_record_with_type; 1966 else if (isa<FunctionDecl>(*Mem)) 1967 DK = diag::err_anonymous_record_with_function; 1968 else if (isa<VarDecl>(*Mem)) 1969 DK = diag::err_anonymous_record_with_static; 1970 Diag((*Mem)->getLocation(), DK) 1971 << (int)Record->isUnion(); 1972 Invalid = true; 1973 } 1974 } 1975 } 1976 1977 if (!Record->isUnion() && !Owner->isRecord()) { 1978 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1979 << (int)getLangOptions().CPlusPlus; 1980 Invalid = true; 1981 } 1982 1983 // Mock up a declarator. 1984 Declarator Dc(DS, Declarator::TypeNameContext); 1985 TypeSourceInfo *TInfo = 0; 1986 GetTypeForDeclarator(Dc, S, &TInfo); 1987 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1988 1989 // Create a declaration for this anonymous struct/union. 1990 NamedDecl *Anon = 0; 1991 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1992 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1993 /*IdentifierInfo=*/0, 1994 Context.getTypeDeclType(Record), 1995 TInfo, 1996 /*BitWidth=*/0, /*Mutable=*/false); 1997 Anon->setAccess(AS_public); 1998 if (getLangOptions().CPlusPlus) 1999 FieldCollector->Add(cast<FieldDecl>(Anon)); 2000 } else { 2001 VarDecl::StorageClass SC; 2002 switch (DS.getStorageClassSpec()) { 2003 default: assert(0 && "Unknown storage class!"); 2004 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2005 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2006 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2007 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2008 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2009 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2010 case DeclSpec::SCS_mutable: 2011 // mutable can only appear on non-static class members, so it's always 2012 // an error here 2013 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2014 Invalid = true; 2015 SC = VarDecl::None; 2016 break; 2017 } 2018 2019 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 2020 /*IdentifierInfo=*/0, 2021 Context.getTypeDeclType(Record), 2022 TInfo, 2023 SC); 2024 } 2025 Anon->setImplicit(); 2026 2027 // Add the anonymous struct/union object to the current 2028 // context. We'll be referencing this object when we refer to one of 2029 // its members. 2030 Owner->addDecl(Anon); 2031 2032 // Inject the members of the anonymous struct/union into the owning 2033 // context and into the identifier resolver chain for name lookup 2034 // purposes. 2035 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 2036 Invalid = true; 2037 2038 // Mark this as an anonymous struct/union type. Note that we do not 2039 // do this until after we have already checked and injected the 2040 // members of this anonymous struct/union type, because otherwise 2041 // the members could be injected twice: once by DeclContext when it 2042 // builds its lookup table, and once by 2043 // InjectAnonymousStructOrUnionMembers. 2044 Record->setAnonymousStructOrUnion(true); 2045 2046 if (Invalid) 2047 Anon->setInvalidDecl(); 2048 2049 return DeclPtrTy::make(Anon); 2050} 2051 2052 2053/// GetNameForDeclarator - Determine the full declaration name for the 2054/// given Declarator. 2055DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 2056 return GetNameFromUnqualifiedId(D.getName()); 2057} 2058 2059/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 2060DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2061 switch (Name.getKind()) { 2062 case UnqualifiedId::IK_Identifier: 2063 return DeclarationName(Name.Identifier); 2064 2065 case UnqualifiedId::IK_OperatorFunctionId: 2066 return Context.DeclarationNames.getCXXOperatorName( 2067 Name.OperatorFunctionId.Operator); 2068 2069 case UnqualifiedId::IK_LiteralOperatorId: 2070 return Context.DeclarationNames.getCXXLiteralOperatorName( 2071 Name.Identifier); 2072 2073 case UnqualifiedId::IK_ConversionFunctionId: { 2074 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 2075 if (Ty.isNull()) 2076 return DeclarationName(); 2077 2078 return Context.DeclarationNames.getCXXConversionFunctionName( 2079 Context.getCanonicalType(Ty)); 2080 } 2081 2082 case UnqualifiedId::IK_ConstructorName: { 2083 QualType Ty = GetTypeFromParser(Name.ConstructorName); 2084 if (Ty.isNull()) 2085 return DeclarationName(); 2086 2087 return Context.DeclarationNames.getCXXConstructorName( 2088 Context.getCanonicalType(Ty)); 2089 } 2090 2091 case UnqualifiedId::IK_ConstructorTemplateId: { 2092 // In well-formed code, we can only have a constructor 2093 // template-id that refers to the current context, so go there 2094 // to find the actual type being constructed. 2095 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2096 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2097 return DeclarationName(); 2098 2099 // Determine the type of the class being constructed. 2100 QualType CurClassType; 2101 if (ClassTemplateDecl *ClassTemplate 2102 = CurClass->getDescribedClassTemplate()) 2103 CurClassType = ClassTemplate->getInjectedClassNameType(Context); 2104 else 2105 CurClassType = Context.getTypeDeclType(CurClass); 2106 2107 // FIXME: Check two things: that the template-id names the same type as 2108 // CurClassType, and that the template-id does not occur when the name 2109 // was qualified. 2110 2111 return Context.DeclarationNames.getCXXConstructorName( 2112 Context.getCanonicalType(CurClassType)); 2113 } 2114 2115 case UnqualifiedId::IK_DestructorName: { 2116 QualType Ty = GetTypeFromParser(Name.DestructorName); 2117 if (Ty.isNull()) 2118 return DeclarationName(); 2119 2120 return Context.DeclarationNames.getCXXDestructorName( 2121 Context.getCanonicalType(Ty)); 2122 } 2123 2124 case UnqualifiedId::IK_TemplateId: { 2125 TemplateName TName 2126 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2127 return Context.getNameForTemplate(TName); 2128 } 2129 } 2130 2131 assert(false && "Unknown name kind"); 2132 return DeclarationName(); 2133} 2134 2135/// isNearlyMatchingFunction - Determine whether the C++ functions 2136/// Declaration and Definition are "nearly" matching. This heuristic 2137/// is used to improve diagnostics in the case where an out-of-line 2138/// function definition doesn't match any declaration within 2139/// the class or namespace. 2140static bool isNearlyMatchingFunction(ASTContext &Context, 2141 FunctionDecl *Declaration, 2142 FunctionDecl *Definition) { 2143 if (Declaration->param_size() != Definition->param_size()) 2144 return false; 2145 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2146 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2147 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2148 2149 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2150 DefParamTy.getNonReferenceType())) 2151 return false; 2152 } 2153 2154 return true; 2155} 2156 2157Sema::DeclPtrTy 2158Sema::HandleDeclarator(Scope *S, Declarator &D, 2159 MultiTemplateParamsArg TemplateParamLists, 2160 bool IsFunctionDefinition) { 2161 DeclarationName Name = GetNameForDeclarator(D); 2162 2163 // All of these full declarators require an identifier. If it doesn't have 2164 // one, the ParsedFreeStandingDeclSpec action should be used. 2165 if (!Name) { 2166 if (!D.isInvalidType()) // Reject this if we think it is valid. 2167 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2168 diag::err_declarator_need_ident) 2169 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2170 return DeclPtrTy(); 2171 } 2172 2173 // The scope passed in may not be a decl scope. Zip up the scope tree until 2174 // we find one that is. 2175 while ((S->getFlags() & Scope::DeclScope) == 0 || 2176 (S->getFlags() & Scope::TemplateParamScope) != 0) 2177 S = S->getParent(); 2178 2179 // If this is an out-of-line definition of a member of a class template 2180 // or class template partial specialization, we may need to rebuild the 2181 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 2182 // for more information. 2183 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 2184 // handle expressions properly. 2185 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 2186 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 2187 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 2188 (DS.getTypeSpecType() == DeclSpec::TST_typename || 2189 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 2190 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 2191 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 2192 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 2193 // FIXME: Preserve type source info. 2194 QualType T = GetTypeFromParser(DS.getTypeRep()); 2195 2196 DeclContext *SavedContext = CurContext; 2197 CurContext = DC; 2198 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 2199 CurContext = SavedContext; 2200 2201 if (T.isNull()) 2202 return DeclPtrTy(); 2203 DS.UpdateTypeRep(T.getAsOpaquePtr()); 2204 } 2205 } 2206 2207 DeclContext *DC; 2208 NamedDecl *New; 2209 2210 TypeSourceInfo *TInfo = 0; 2211 QualType R = GetTypeForDeclarator(D, S, &TInfo); 2212 2213 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2214 ForRedeclaration); 2215 2216 // See if this is a redefinition of a variable in the same scope. 2217 if (D.getCXXScopeSpec().isInvalid()) { 2218 DC = CurContext; 2219 D.setInvalidType(); 2220 } else if (!D.getCXXScopeSpec().isSet()) { 2221 bool IsLinkageLookup = false; 2222 2223 // If the declaration we're planning to build will be a function 2224 // or object with linkage, then look for another declaration with 2225 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2226 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2227 /* Do nothing*/; 2228 else if (R->isFunctionType()) { 2229 if (CurContext->isFunctionOrMethod() || 2230 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2231 IsLinkageLookup = true; 2232 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2233 IsLinkageLookup = true; 2234 else if (CurContext->getLookupContext()->isTranslationUnit() && 2235 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2236 IsLinkageLookup = true; 2237 2238 if (IsLinkageLookup) 2239 Previous.clear(LookupRedeclarationWithLinkage); 2240 2241 DC = CurContext; 2242 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2243 } else { // Something like "int foo::x;" 2244 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2245 2246 if (!DC) { 2247 // If we could not compute the declaration context, it's because the 2248 // declaration context is dependent but does not refer to a class, 2249 // class template, or class template partial specialization. Complain 2250 // and return early, to avoid the coming semantic disaster. 2251 Diag(D.getIdentifierLoc(), 2252 diag::err_template_qualified_declarator_no_match) 2253 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2254 << D.getCXXScopeSpec().getRange(); 2255 return DeclPtrTy(); 2256 } 2257 2258 if (!DC->isDependentContext() && 2259 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2260 return DeclPtrTy(); 2261 2262 LookupQualifiedName(Previous, DC); 2263 2264 // Don't consider using declarations as previous declarations for 2265 // out-of-line members. 2266 RemoveUsingDecls(Previous); 2267 2268 // C++ 7.3.1.2p2: 2269 // Members (including explicit specializations of templates) of a named 2270 // namespace can also be defined outside that namespace by explicit 2271 // qualification of the name being defined, provided that the entity being 2272 // defined was already declared in the namespace and the definition appears 2273 // after the point of declaration in a namespace that encloses the 2274 // declarations namespace. 2275 // 2276 // Note that we only check the context at this point. We don't yet 2277 // have enough information to make sure that PrevDecl is actually 2278 // the declaration we want to match. For example, given: 2279 // 2280 // class X { 2281 // void f(); 2282 // void f(float); 2283 // }; 2284 // 2285 // void X::f(int) { } // ill-formed 2286 // 2287 // In this case, PrevDecl will point to the overload set 2288 // containing the two f's declared in X, but neither of them 2289 // matches. 2290 2291 // First check whether we named the global scope. 2292 if (isa<TranslationUnitDecl>(DC)) { 2293 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2294 << Name << D.getCXXScopeSpec().getRange(); 2295 } else { 2296 DeclContext *Cur = CurContext; 2297 while (isa<LinkageSpecDecl>(Cur)) 2298 Cur = Cur->getParent(); 2299 if (!Cur->Encloses(DC)) { 2300 // The qualifying scope doesn't enclose the original declaration. 2301 // Emit diagnostic based on current scope. 2302 SourceLocation L = D.getIdentifierLoc(); 2303 SourceRange R = D.getCXXScopeSpec().getRange(); 2304 if (isa<FunctionDecl>(Cur)) 2305 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2306 else 2307 Diag(L, diag::err_invalid_declarator_scope) 2308 << Name << cast<NamedDecl>(DC) << R; 2309 D.setInvalidType(); 2310 } 2311 } 2312 } 2313 2314 if (Previous.isSingleResult() && 2315 Previous.getFoundDecl()->isTemplateParameter()) { 2316 // Maybe we will complain about the shadowed template parameter. 2317 if (!D.isInvalidType()) 2318 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2319 Previous.getFoundDecl())) 2320 D.setInvalidType(); 2321 2322 // Just pretend that we didn't see the previous declaration. 2323 Previous.clear(); 2324 } 2325 2326 // In C++, the previous declaration we find might be a tag type 2327 // (class or enum). In this case, the new declaration will hide the 2328 // tag type. Note that this does does not apply if we're declaring a 2329 // typedef (C++ [dcl.typedef]p4). 2330 if (Previous.isSingleTagDecl() && 2331 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2332 Previous.clear(); 2333 2334 bool Redeclaration = false; 2335 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2336 if (TemplateParamLists.size()) { 2337 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2338 return DeclPtrTy(); 2339 } 2340 2341 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2342 } else if (R->isFunctionType()) { 2343 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2344 move(TemplateParamLists), 2345 IsFunctionDefinition, Redeclaration); 2346 } else { 2347 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2348 move(TemplateParamLists), 2349 Redeclaration); 2350 } 2351 2352 if (New == 0) 2353 return DeclPtrTy(); 2354 2355 // If this has an identifier and is not an invalid redeclaration or 2356 // function template specialization, add it to the scope stack. 2357 if (Name && !(Redeclaration && New->isInvalidDecl())) 2358 PushOnScopeChains(New, S); 2359 2360 return DeclPtrTy::make(New); 2361} 2362 2363/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2364/// types into constant array types in certain situations which would otherwise 2365/// be errors (for GCC compatibility). 2366static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2367 ASTContext &Context, 2368 bool &SizeIsNegative) { 2369 // This method tries to turn a variable array into a constant 2370 // array even when the size isn't an ICE. This is necessary 2371 // for compatibility with code that depends on gcc's buggy 2372 // constant expression folding, like struct {char x[(int)(char*)2];} 2373 SizeIsNegative = false; 2374 2375 QualifierCollector Qs; 2376 const Type *Ty = Qs.strip(T); 2377 2378 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2379 QualType Pointee = PTy->getPointeeType(); 2380 QualType FixedType = 2381 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2382 if (FixedType.isNull()) return FixedType; 2383 FixedType = Context.getPointerType(FixedType); 2384 return Qs.apply(FixedType); 2385 } 2386 2387 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2388 if (!VLATy) 2389 return QualType(); 2390 // FIXME: We should probably handle this case 2391 if (VLATy->getElementType()->isVariablyModifiedType()) 2392 return QualType(); 2393 2394 Expr::EvalResult EvalResult; 2395 if (!VLATy->getSizeExpr() || 2396 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2397 !EvalResult.Val.isInt()) 2398 return QualType(); 2399 2400 llvm::APSInt &Res = EvalResult.Val.getInt(); 2401 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2402 // TODO: preserve the size expression in declarator info 2403 return Context.getConstantArrayType(VLATy->getElementType(), 2404 Res, ArrayType::Normal, 0); 2405 } 2406 2407 SizeIsNegative = true; 2408 return QualType(); 2409} 2410 2411/// \brief Register the given locally-scoped external C declaration so 2412/// that it can be found later for redeclarations 2413void 2414Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2415 const LookupResult &Previous, 2416 Scope *S) { 2417 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2418 "Decl is not a locally-scoped decl!"); 2419 // Note that we have a locally-scoped external with this name. 2420 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2421 2422 if (!Previous.isSingleResult()) 2423 return; 2424 2425 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2426 2427 // If there was a previous declaration of this variable, it may be 2428 // in our identifier chain. Update the identifier chain with the new 2429 // declaration. 2430 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2431 // The previous declaration was found on the identifer resolver 2432 // chain, so remove it from its scope. 2433 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2434 S = S->getParent(); 2435 2436 if (S) 2437 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2438 } 2439} 2440 2441/// \brief Diagnose function specifiers on a declaration of an identifier that 2442/// does not identify a function. 2443void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2444 // FIXME: We should probably indicate the identifier in question to avoid 2445 // confusion for constructs like "inline int a(), b;" 2446 if (D.getDeclSpec().isInlineSpecified()) 2447 Diag(D.getDeclSpec().getInlineSpecLoc(), 2448 diag::err_inline_non_function); 2449 2450 if (D.getDeclSpec().isVirtualSpecified()) 2451 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2452 diag::err_virtual_non_function); 2453 2454 if (D.getDeclSpec().isExplicitSpecified()) 2455 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2456 diag::err_explicit_non_function); 2457} 2458 2459NamedDecl* 2460Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2461 QualType R, TypeSourceInfo *TInfo, 2462 LookupResult &Previous, bool &Redeclaration) { 2463 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2464 if (D.getCXXScopeSpec().isSet()) { 2465 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2466 << D.getCXXScopeSpec().getRange(); 2467 D.setInvalidType(); 2468 // Pretend we didn't see the scope specifier. 2469 DC = 0; 2470 } 2471 2472 if (getLangOptions().CPlusPlus) { 2473 // Check that there are no default arguments (C++ only). 2474 CheckExtraCXXDefaultArguments(D); 2475 } 2476 2477 DiagnoseFunctionSpecifiers(D); 2478 2479 if (D.getDeclSpec().isThreadSpecified()) 2480 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2481 2482 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2483 if (!NewTD) return 0; 2484 2485 // Handle attributes prior to checking for duplicates in MergeVarDecl 2486 ProcessDeclAttributes(S, NewTD, D); 2487 2488 // Merge the decl with the existing one if appropriate. If the decl is 2489 // in an outer scope, it isn't the same thing. 2490 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2491 if (!Previous.empty()) { 2492 Redeclaration = true; 2493 MergeTypeDefDecl(NewTD, Previous); 2494 } 2495 2496 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2497 // then it shall have block scope. 2498 QualType T = NewTD->getUnderlyingType(); 2499 if (T->isVariablyModifiedType()) { 2500 CurFunctionNeedsScopeChecking = true; 2501 2502 if (S->getFnParent() == 0) { 2503 bool SizeIsNegative; 2504 QualType FixedTy = 2505 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2506 if (!FixedTy.isNull()) { 2507 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2508 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2509 } else { 2510 if (SizeIsNegative) 2511 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2512 else if (T->isVariableArrayType()) 2513 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2514 else 2515 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2516 NewTD->setInvalidDecl(); 2517 } 2518 } 2519 } 2520 2521 // If this is the C FILE type, notify the AST context. 2522 if (IdentifierInfo *II = NewTD->getIdentifier()) 2523 if (!NewTD->isInvalidDecl() && 2524 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2525 if (II->isStr("FILE")) 2526 Context.setFILEDecl(NewTD); 2527 else if (II->isStr("jmp_buf")) 2528 Context.setjmp_bufDecl(NewTD); 2529 else if (II->isStr("sigjmp_buf")) 2530 Context.setsigjmp_bufDecl(NewTD); 2531 } 2532 2533 return NewTD; 2534} 2535 2536/// \brief Determines whether the given declaration is an out-of-scope 2537/// previous declaration. 2538/// 2539/// This routine should be invoked when name lookup has found a 2540/// previous declaration (PrevDecl) that is not in the scope where a 2541/// new declaration by the same name is being introduced. If the new 2542/// declaration occurs in a local scope, previous declarations with 2543/// linkage may still be considered previous declarations (C99 2544/// 6.2.2p4-5, C++ [basic.link]p6). 2545/// 2546/// \param PrevDecl the previous declaration found by name 2547/// lookup 2548/// 2549/// \param DC the context in which the new declaration is being 2550/// declared. 2551/// 2552/// \returns true if PrevDecl is an out-of-scope previous declaration 2553/// for a new delcaration with the same name. 2554static bool 2555isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2556 ASTContext &Context) { 2557 if (!PrevDecl) 2558 return 0; 2559 2560 if (!PrevDecl->hasLinkage()) 2561 return false; 2562 2563 if (Context.getLangOptions().CPlusPlus) { 2564 // C++ [basic.link]p6: 2565 // If there is a visible declaration of an entity with linkage 2566 // having the same name and type, ignoring entities declared 2567 // outside the innermost enclosing namespace scope, the block 2568 // scope declaration declares that same entity and receives the 2569 // linkage of the previous declaration. 2570 DeclContext *OuterContext = DC->getLookupContext(); 2571 if (!OuterContext->isFunctionOrMethod()) 2572 // This rule only applies to block-scope declarations. 2573 return false; 2574 else { 2575 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2576 if (PrevOuterContext->isRecord()) 2577 // We found a member function: ignore it. 2578 return false; 2579 else { 2580 // Find the innermost enclosing namespace for the new and 2581 // previous declarations. 2582 while (!OuterContext->isFileContext()) 2583 OuterContext = OuterContext->getParent(); 2584 while (!PrevOuterContext->isFileContext()) 2585 PrevOuterContext = PrevOuterContext->getParent(); 2586 2587 // The previous declaration is in a different namespace, so it 2588 // isn't the same function. 2589 if (OuterContext->getPrimaryContext() != 2590 PrevOuterContext->getPrimaryContext()) 2591 return false; 2592 } 2593 } 2594 } 2595 2596 return true; 2597} 2598 2599NamedDecl* 2600Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2601 QualType R, TypeSourceInfo *TInfo, 2602 LookupResult &Previous, 2603 MultiTemplateParamsArg TemplateParamLists, 2604 bool &Redeclaration) { 2605 DeclarationName Name = GetNameForDeclarator(D); 2606 2607 // Check that there are no default arguments (C++ only). 2608 if (getLangOptions().CPlusPlus) 2609 CheckExtraCXXDefaultArguments(D); 2610 2611 VarDecl *NewVD; 2612 VarDecl::StorageClass SC; 2613 switch (D.getDeclSpec().getStorageClassSpec()) { 2614 default: assert(0 && "Unknown storage class!"); 2615 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2616 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2617 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2618 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2619 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2620 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2621 case DeclSpec::SCS_mutable: 2622 // mutable can only appear on non-static class members, so it's always 2623 // an error here 2624 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2625 D.setInvalidType(); 2626 SC = VarDecl::None; 2627 break; 2628 } 2629 2630 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2631 if (!II) { 2632 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2633 << Name.getAsString(); 2634 return 0; 2635 } 2636 2637 DiagnoseFunctionSpecifiers(D); 2638 2639 if (!DC->isRecord() && S->getFnParent() == 0) { 2640 // C99 6.9p2: The storage-class specifiers auto and register shall not 2641 // appear in the declaration specifiers in an external declaration. 2642 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2643 2644 // If this is a register variable with an asm label specified, then this 2645 // is a GNU extension. 2646 if (SC == VarDecl::Register && D.getAsmLabel()) 2647 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2648 else 2649 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2650 D.setInvalidType(); 2651 } 2652 } 2653 if (DC->isRecord() && !CurContext->isRecord()) { 2654 // This is an out-of-line definition of a static data member. 2655 if (SC == VarDecl::Static) { 2656 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2657 diag::err_static_out_of_line) 2658 << CodeModificationHint::CreateRemoval( 2659 D.getDeclSpec().getStorageClassSpecLoc()); 2660 } else if (SC == VarDecl::None) 2661 SC = VarDecl::Static; 2662 } 2663 if (SC == VarDecl::Static) { 2664 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2665 if (RD->isLocalClass()) 2666 Diag(D.getIdentifierLoc(), 2667 diag::err_static_data_member_not_allowed_in_local_class) 2668 << Name << RD->getDeclName(); 2669 } 2670 } 2671 2672 // Match up the template parameter lists with the scope specifier, then 2673 // determine whether we have a template or a template specialization. 2674 bool isExplicitSpecialization = false; 2675 if (TemplateParameterList *TemplateParams 2676 = MatchTemplateParametersToScopeSpecifier( 2677 D.getDeclSpec().getSourceRange().getBegin(), 2678 D.getCXXScopeSpec(), 2679 (TemplateParameterList**)TemplateParamLists.get(), 2680 TemplateParamLists.size(), 2681 isExplicitSpecialization)) { 2682 if (TemplateParams->size() > 0) { 2683 // There is no such thing as a variable template. 2684 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2685 << II 2686 << SourceRange(TemplateParams->getTemplateLoc(), 2687 TemplateParams->getRAngleLoc()); 2688 return 0; 2689 } else { 2690 // There is an extraneous 'template<>' for this variable. Complain 2691 // about it, but allow the declaration of the variable. 2692 Diag(TemplateParams->getTemplateLoc(), 2693 diag::err_template_variable_noparams) 2694 << II 2695 << SourceRange(TemplateParams->getTemplateLoc(), 2696 TemplateParams->getRAngleLoc()); 2697 2698 isExplicitSpecialization = true; 2699 } 2700 } 2701 2702 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2703 II, R, TInfo, SC); 2704 2705 if (D.isInvalidType()) 2706 NewVD->setInvalidDecl(); 2707 2708 if (D.getDeclSpec().isThreadSpecified()) { 2709 if (NewVD->hasLocalStorage()) 2710 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2711 else if (!Context.Target.isTLSSupported()) 2712 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2713 else 2714 NewVD->setThreadSpecified(true); 2715 } 2716 2717 // Set the lexical context. If the declarator has a C++ scope specifier, the 2718 // lexical context will be different from the semantic context. 2719 NewVD->setLexicalDeclContext(CurContext); 2720 2721 // Handle attributes prior to checking for duplicates in MergeVarDecl 2722 ProcessDeclAttributes(S, NewVD, D); 2723 2724 // Handle GNU asm-label extension (encoded as an attribute). 2725 if (Expr *E = (Expr*) D.getAsmLabel()) { 2726 // The parser guarantees this is a string. 2727 StringLiteral *SE = cast<StringLiteral>(E); 2728 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2729 } 2730 2731 // Don't consider existing declarations that are in a different 2732 // scope and are out-of-semantic-context declarations (if the new 2733 // declaration has linkage). 2734 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2735 2736 // Merge the decl with the existing one if appropriate. 2737 if (!Previous.empty()) { 2738 if (Previous.isSingleResult() && 2739 isa<FieldDecl>(Previous.getFoundDecl()) && 2740 D.getCXXScopeSpec().isSet()) { 2741 // The user tried to define a non-static data member 2742 // out-of-line (C++ [dcl.meaning]p1). 2743 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2744 << D.getCXXScopeSpec().getRange(); 2745 Previous.clear(); 2746 NewVD->setInvalidDecl(); 2747 } 2748 } else if (D.getCXXScopeSpec().isSet()) { 2749 // No previous declaration in the qualifying scope. 2750 Diag(D.getIdentifierLoc(), diag::err_no_member) 2751 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2752 << D.getCXXScopeSpec().getRange(); 2753 NewVD->setInvalidDecl(); 2754 } 2755 2756 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2757 2758 // This is an explicit specialization of a static data member. Check it. 2759 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2760 CheckMemberSpecialization(NewVD, Previous)) 2761 NewVD->setInvalidDecl(); 2762 2763 // attributes declared post-definition are currently ignored 2764 if (Previous.isSingleResult()) { 2765 const VarDecl *Def = 0; 2766 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2767 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2768 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2769 Diag(Def->getLocation(), diag::note_previous_definition); 2770 } 2771 } 2772 2773 // If this is a locally-scoped extern C variable, update the map of 2774 // such variables. 2775 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2776 !NewVD->isInvalidDecl()) 2777 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2778 2779 return NewVD; 2780} 2781 2782/// \brief Perform semantic checking on a newly-created variable 2783/// declaration. 2784/// 2785/// This routine performs all of the type-checking required for a 2786/// variable declaration once it has been built. It is used both to 2787/// check variables after they have been parsed and their declarators 2788/// have been translated into a declaration, and to check variables 2789/// that have been instantiated from a template. 2790/// 2791/// Sets NewVD->isInvalidDecl() if an error was encountered. 2792void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2793 LookupResult &Previous, 2794 bool &Redeclaration) { 2795 // If the decl is already known invalid, don't check it. 2796 if (NewVD->isInvalidDecl()) 2797 return; 2798 2799 QualType T = NewVD->getType(); 2800 2801 if (T->isObjCInterfaceType()) { 2802 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2803 return NewVD->setInvalidDecl(); 2804 } 2805 2806 // Emit an error if an address space was applied to decl with local storage. 2807 // This includes arrays of objects with address space qualifiers, but not 2808 // automatic variables that point to other address spaces. 2809 // ISO/IEC TR 18037 S5.1.2 2810 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2811 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2812 return NewVD->setInvalidDecl(); 2813 } 2814 2815 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2816 && !NewVD->hasAttr<BlocksAttr>()) 2817 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2818 2819 bool isVM = T->isVariablyModifiedType(); 2820 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2821 NewVD->hasAttr<BlocksAttr>()) 2822 CurFunctionNeedsScopeChecking = true; 2823 2824 if ((isVM && NewVD->hasLinkage()) || 2825 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2826 bool SizeIsNegative; 2827 QualType FixedTy = 2828 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2829 2830 if (FixedTy.isNull() && T->isVariableArrayType()) { 2831 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2832 // FIXME: This won't give the correct result for 2833 // int a[10][n]; 2834 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2835 2836 if (NewVD->isFileVarDecl()) 2837 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2838 << SizeRange; 2839 else if (NewVD->getStorageClass() == VarDecl::Static) 2840 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2841 << SizeRange; 2842 else 2843 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2844 << SizeRange; 2845 return NewVD->setInvalidDecl(); 2846 } 2847 2848 if (FixedTy.isNull()) { 2849 if (NewVD->isFileVarDecl()) 2850 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2851 else 2852 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2853 return NewVD->setInvalidDecl(); 2854 } 2855 2856 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2857 NewVD->setType(FixedTy); 2858 } 2859 2860 if (Previous.empty() && NewVD->isExternC()) { 2861 // Since we did not find anything by this name and we're declaring 2862 // an extern "C" variable, look for a non-visible extern "C" 2863 // declaration with the same name. 2864 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2865 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2866 if (Pos != LocallyScopedExternalDecls.end()) 2867 Previous.addDecl(Pos->second); 2868 } 2869 2870 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2871 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2872 << T; 2873 return NewVD->setInvalidDecl(); 2874 } 2875 2876 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2877 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2878 return NewVD->setInvalidDecl(); 2879 } 2880 2881 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2882 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2883 return NewVD->setInvalidDecl(); 2884 } 2885 2886 if (!Previous.empty()) { 2887 Redeclaration = true; 2888 MergeVarDecl(NewVD, Previous); 2889 } 2890} 2891 2892/// \brief Data used with FindOverriddenMethod 2893struct FindOverriddenMethodData { 2894 Sema *S; 2895 CXXMethodDecl *Method; 2896}; 2897 2898/// \brief Member lookup function that determines whether a given C++ 2899/// method overrides a method in a base class, to be used with 2900/// CXXRecordDecl::lookupInBases(). 2901static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2902 CXXBasePath &Path, 2903 void *UserData) { 2904 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2905 2906 FindOverriddenMethodData *Data 2907 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2908 2909 DeclarationName Name = Data->Method->getDeclName(); 2910 2911 // FIXME: Do we care about other names here too? 2912 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2913 // We really want to find the base class constructor here. 2914 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2915 CanQualType CT = Data->S->Context.getCanonicalType(T); 2916 2917 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2918 } 2919 2920 for (Path.Decls = BaseRecord->lookup(Name); 2921 Path.Decls.first != Path.Decls.second; 2922 ++Path.Decls.first) { 2923 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2924 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2925 return true; 2926 } 2927 } 2928 2929 return false; 2930} 2931 2932/// AddOverriddenMethods - See if a method overrides any in the base classes, 2933/// and if so, check that it's a valid override and remember it. 2934void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2935 // Look for virtual methods in base classes that this method might override. 2936 CXXBasePaths Paths; 2937 FindOverriddenMethodData Data; 2938 Data.Method = MD; 2939 Data.S = this; 2940 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2941 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2942 E = Paths.found_decls_end(); I != E; ++I) { 2943 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2944 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2945 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2946 !CheckOverridingFunctionAttributes(MD, OldMD)) 2947 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2948 } 2949 } 2950 } 2951} 2952 2953NamedDecl* 2954Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2955 QualType R, TypeSourceInfo *TInfo, 2956 LookupResult &Previous, 2957 MultiTemplateParamsArg TemplateParamLists, 2958 bool IsFunctionDefinition, bool &Redeclaration) { 2959 assert(R.getTypePtr()->isFunctionType()); 2960 2961 DeclarationName Name = GetNameForDeclarator(D); 2962 FunctionDecl::StorageClass SC = FunctionDecl::None; 2963 switch (D.getDeclSpec().getStorageClassSpec()) { 2964 default: assert(0 && "Unknown storage class!"); 2965 case DeclSpec::SCS_auto: 2966 case DeclSpec::SCS_register: 2967 case DeclSpec::SCS_mutable: 2968 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2969 diag::err_typecheck_sclass_func); 2970 D.setInvalidType(); 2971 break; 2972 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2973 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2974 case DeclSpec::SCS_static: { 2975 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2976 // C99 6.7.1p5: 2977 // The declaration of an identifier for a function that has 2978 // block scope shall have no explicit storage-class specifier 2979 // other than extern 2980 // See also (C++ [dcl.stc]p4). 2981 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2982 diag::err_static_block_func); 2983 SC = FunctionDecl::None; 2984 } else 2985 SC = FunctionDecl::Static; 2986 break; 2987 } 2988 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2989 } 2990 2991 if (D.getDeclSpec().isThreadSpecified()) 2992 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2993 2994 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2995 bool isInline = D.getDeclSpec().isInlineSpecified(); 2996 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2997 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2998 2999 // Check that the return type is not an abstract class type. 3000 // For record types, this is done by the AbstractClassUsageDiagnoser once 3001 // the class has been completely parsed. 3002 if (!DC->isRecord() && 3003 RequireNonAbstractType(D.getIdentifierLoc(), 3004 R->getAs<FunctionType>()->getResultType(), 3005 diag::err_abstract_type_in_decl, 3006 AbstractReturnType)) 3007 D.setInvalidType(); 3008 3009 // Do not allow returning a objc interface by-value. 3010 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 3011 Diag(D.getIdentifierLoc(), 3012 diag::err_object_cannot_be_passed_returned_by_value) << 0 3013 << R->getAs<FunctionType>()->getResultType(); 3014 D.setInvalidType(); 3015 } 3016 3017 bool isVirtualOkay = false; 3018 FunctionDecl *NewFD; 3019 3020 if (isFriend) { 3021 // C++ [class.friend]p5 3022 // A function can be defined in a friend declaration of a 3023 // class . . . . Such a function is implicitly inline. 3024 isInline |= IsFunctionDefinition; 3025 } 3026 3027 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3028 // This is a C++ constructor declaration. 3029 assert(DC->isRecord() && 3030 "Constructors can only be declared in a member context"); 3031 3032 R = CheckConstructorDeclarator(D, R, SC); 3033 3034 // Create the new declaration 3035 NewFD = CXXConstructorDecl::Create(Context, 3036 cast<CXXRecordDecl>(DC), 3037 D.getIdentifierLoc(), Name, R, TInfo, 3038 isExplicit, isInline, 3039 /*isImplicitlyDeclared=*/false); 3040 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3041 // This is a C++ destructor declaration. 3042 if (DC->isRecord()) { 3043 R = CheckDestructorDeclarator(D, SC); 3044 3045 NewFD = CXXDestructorDecl::Create(Context, 3046 cast<CXXRecordDecl>(DC), 3047 D.getIdentifierLoc(), Name, R, 3048 isInline, 3049 /*isImplicitlyDeclared=*/false); 3050 3051 isVirtualOkay = true; 3052 } else { 3053 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3054 3055 // Create a FunctionDecl to satisfy the function definition parsing 3056 // code path. 3057 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3058 Name, R, TInfo, SC, isInline, 3059 /*hasPrototype=*/true); 3060 D.setInvalidType(); 3061 } 3062 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3063 if (!DC->isRecord()) { 3064 Diag(D.getIdentifierLoc(), 3065 diag::err_conv_function_not_member); 3066 return 0; 3067 } 3068 3069 CheckConversionDeclarator(D, R, SC); 3070 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3071 D.getIdentifierLoc(), Name, R, TInfo, 3072 isInline, isExplicit); 3073 3074 isVirtualOkay = true; 3075 } else if (DC->isRecord()) { 3076 // If the of the function is the same as the name of the record, then this 3077 // must be an invalid constructor that has a return type. 3078 // (The parser checks for a return type and makes the declarator a 3079 // constructor if it has no return type). 3080 // must have an invalid constructor that has a return type 3081 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3082 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3083 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3084 << SourceRange(D.getIdentifierLoc()); 3085 return 0; 3086 } 3087 3088 bool isStatic = SC == FunctionDecl::Static; 3089 3090 // [class.free]p1: 3091 // Any allocation function for a class T is a static member 3092 // (even if not explicitly declared static). 3093 if (Name.getCXXOverloadedOperator() == OO_New || 3094 Name.getCXXOverloadedOperator() == OO_Array_New) 3095 isStatic = true; 3096 3097 // [class.free]p6 Any deallocation function for a class X is a static member 3098 // (even if not explicitly declared static). 3099 if (Name.getCXXOverloadedOperator() == OO_Delete || 3100 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3101 isStatic = true; 3102 3103 // This is a C++ method declaration. 3104 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3105 D.getIdentifierLoc(), Name, R, TInfo, 3106 isStatic, isInline); 3107 3108 isVirtualOkay = !isStatic; 3109 } else { 3110 // Determine whether the function was written with a 3111 // prototype. This true when: 3112 // - we're in C++ (where every function has a prototype), 3113 // - there is a prototype in the declarator, or 3114 // - the type R of the function is some kind of typedef or other reference 3115 // to a type name (which eventually refers to a function type). 3116 bool HasPrototype = 3117 getLangOptions().CPlusPlus || 3118 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3119 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3120 3121 NewFD = FunctionDecl::Create(Context, DC, 3122 D.getIdentifierLoc(), 3123 Name, R, TInfo, SC, isInline, HasPrototype); 3124 } 3125 3126 if (D.isInvalidType()) 3127 NewFD->setInvalidDecl(); 3128 3129 // Set the lexical context. If the declarator has a C++ 3130 // scope specifier, or is the object of a friend declaration, the 3131 // lexical context will be different from the semantic context. 3132 NewFD->setLexicalDeclContext(CurContext); 3133 3134 // Match up the template parameter lists with the scope specifier, then 3135 // determine whether we have a template or a template specialization. 3136 FunctionTemplateDecl *FunctionTemplate = 0; 3137 bool isExplicitSpecialization = false; 3138 bool isFunctionTemplateSpecialization = false; 3139 if (TemplateParameterList *TemplateParams 3140 = MatchTemplateParametersToScopeSpecifier( 3141 D.getDeclSpec().getSourceRange().getBegin(), 3142 D.getCXXScopeSpec(), 3143 (TemplateParameterList**)TemplateParamLists.get(), 3144 TemplateParamLists.size(), 3145 isExplicitSpecialization)) { 3146 if (TemplateParams->size() > 0) { 3147 // This is a function template 3148 3149 // Check that we can declare a template here. 3150 if (CheckTemplateDeclScope(S, TemplateParams)) 3151 return 0; 3152 3153 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3154 NewFD->getLocation(), 3155 Name, TemplateParams, 3156 NewFD); 3157 FunctionTemplate->setLexicalDeclContext(CurContext); 3158 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3159 } else { 3160 // This is a function template specialization. 3161 isFunctionTemplateSpecialization = true; 3162 } 3163 3164 // FIXME: Free this memory properly. 3165 TemplateParamLists.release(); 3166 } 3167 3168 // C++ [dcl.fct.spec]p5: 3169 // The virtual specifier shall only be used in declarations of 3170 // nonstatic class member functions that appear within a 3171 // member-specification of a class declaration; see 10.3. 3172 // 3173 if (isVirtual && !NewFD->isInvalidDecl()) { 3174 if (!isVirtualOkay) { 3175 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3176 diag::err_virtual_non_function); 3177 } else if (!CurContext->isRecord()) { 3178 // 'virtual' was specified outside of the class. 3179 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3180 << CodeModificationHint::CreateRemoval( 3181 D.getDeclSpec().getVirtualSpecLoc()); 3182 } else { 3183 // Okay: Add virtual to the method. 3184 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3185 CurClass->setMethodAsVirtual(NewFD); 3186 } 3187 } 3188 3189 // Filter out previous declarations that don't match the scope. 3190 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3191 3192 if (isFriend) { 3193 // DC is the namespace in which the function is being declared. 3194 assert((DC->isFileContext() || !Previous.empty()) && 3195 "previously-undeclared friend function being created " 3196 "in a non-namespace context"); 3197 3198 if (FunctionTemplate) { 3199 FunctionTemplate->setObjectOfFriendDecl( 3200 /* PreviouslyDeclared= */ !Previous.empty()); 3201 FunctionTemplate->setAccess(AS_public); 3202 } 3203 else 3204 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 3205 3206 NewFD->setAccess(AS_public); 3207 } 3208 3209 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3210 !CurContext->isRecord()) { 3211 // C++ [class.static]p1: 3212 // A data or function member of a class may be declared static 3213 // in a class definition, in which case it is a static member of 3214 // the class. 3215 3216 // Complain about the 'static' specifier if it's on an out-of-line 3217 // member function definition. 3218 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3219 diag::err_static_out_of_line) 3220 << CodeModificationHint::CreateRemoval( 3221 D.getDeclSpec().getStorageClassSpecLoc()); 3222 } 3223 3224 // Handle GNU asm-label extension (encoded as an attribute). 3225 if (Expr *E = (Expr*) D.getAsmLabel()) { 3226 // The parser guarantees this is a string. 3227 StringLiteral *SE = cast<StringLiteral>(E); 3228 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 3229 } 3230 3231 // Copy the parameter declarations from the declarator D to the function 3232 // declaration NewFD, if they are available. First scavenge them into Params. 3233 llvm::SmallVector<ParmVarDecl*, 16> Params; 3234 if (D.getNumTypeObjects() > 0) { 3235 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3236 3237 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3238 // function that takes no arguments, not a function that takes a 3239 // single void argument. 3240 // We let through "const void" here because Sema::GetTypeForDeclarator 3241 // already checks for that case. 3242 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3243 FTI.ArgInfo[0].Param && 3244 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3245 // Empty arg list, don't push any params. 3246 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3247 3248 // In C++, the empty parameter-type-list must be spelled "void"; a 3249 // typedef of void is not permitted. 3250 if (getLangOptions().CPlusPlus && 3251 Param->getType().getUnqualifiedType() != Context.VoidTy) 3252 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3253 // FIXME: Leaks decl? 3254 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3255 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3256 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3257 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3258 Param->setDeclContext(NewFD); 3259 Params.push_back(Param); 3260 } 3261 } 3262 3263 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3264 // When we're declaring a function with a typedef, typeof, etc as in the 3265 // following example, we'll need to synthesize (unnamed) 3266 // parameters for use in the declaration. 3267 // 3268 // @code 3269 // typedef void fn(int); 3270 // fn f; 3271 // @endcode 3272 3273 // Synthesize a parameter for each argument type. 3274 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3275 AE = FT->arg_type_end(); AI != AE; ++AI) { 3276 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3277 SourceLocation(), 0, 3278 *AI, /*TInfo=*/0, 3279 VarDecl::None, 0); 3280 Param->setImplicit(); 3281 Params.push_back(Param); 3282 } 3283 } else { 3284 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3285 "Should not need args for typedef of non-prototype fn"); 3286 } 3287 // Finally, we know we have the right number of parameters, install them. 3288 NewFD->setParams(Context, Params.data(), Params.size()); 3289 3290 // If the declarator is a template-id, translate the parser's template 3291 // argument list into our AST format. 3292 bool HasExplicitTemplateArgs = false; 3293 TemplateArgumentListInfo TemplateArgs; 3294 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3295 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3296 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3297 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3298 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3299 TemplateId->getTemplateArgs(), 3300 TemplateId->NumArgs); 3301 translateTemplateArguments(TemplateArgsPtr, 3302 TemplateArgs); 3303 TemplateArgsPtr.release(); 3304 3305 HasExplicitTemplateArgs = true; 3306 3307 if (FunctionTemplate) { 3308 // FIXME: Diagnose function template with explicit template 3309 // arguments. 3310 HasExplicitTemplateArgs = false; 3311 } else if (!isFunctionTemplateSpecialization && 3312 !D.getDeclSpec().isFriendSpecified()) { 3313 // We have encountered something that the user meant to be a 3314 // specialization (because it has explicitly-specified template 3315 // arguments) but that was not introduced with a "template<>" (or had 3316 // too few of them). 3317 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3318 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3319 << CodeModificationHint::CreateInsertion( 3320 D.getDeclSpec().getSourceRange().getBegin(), 3321 "template<> "); 3322 isFunctionTemplateSpecialization = true; 3323 } 3324 } 3325 3326 if (isFunctionTemplateSpecialization) { 3327 if (CheckFunctionTemplateSpecialization(NewFD, 3328 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3329 Previous)) 3330 NewFD->setInvalidDecl(); 3331 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3332 CheckMemberSpecialization(NewFD, Previous)) 3333 NewFD->setInvalidDecl(); 3334 3335 // Perform semantic checking on the function declaration. 3336 bool OverloadableAttrRequired = false; // FIXME: HACK! 3337 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3338 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3339 3340 assert((NewFD->isInvalidDecl() || !Redeclaration || 3341 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3342 "previous declaration set still overloaded"); 3343 3344 // If we have a function template, check the template parameter 3345 // list. This will check and merge default template arguments. 3346 if (FunctionTemplate) { 3347 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3348 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3349 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3350 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3351 : TPC_FunctionTemplate); 3352 } 3353 3354 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3355 // An out-of-line member function declaration must also be a 3356 // definition (C++ [dcl.meaning]p1). 3357 // Note that this is not the case for explicit specializations of 3358 // function templates or member functions of class templates, per 3359 // C++ [temp.expl.spec]p2. 3360 if (!IsFunctionDefinition && !isFriend && 3361 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3362 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3363 << D.getCXXScopeSpec().getRange(); 3364 NewFD->setInvalidDecl(); 3365 } else if (!Redeclaration && 3366 !(isFriend && CurContext->isDependentContext())) { 3367 // The user tried to provide an out-of-line definition for a 3368 // function that is a member of a class or namespace, but there 3369 // was no such member function declared (C++ [class.mfct]p2, 3370 // C++ [namespace.memdef]p2). For example: 3371 // 3372 // class X { 3373 // void f() const; 3374 // }; 3375 // 3376 // void X::f() { } // ill-formed 3377 // 3378 // Complain about this problem, and attempt to suggest close 3379 // matches (e.g., those that differ only in cv-qualifiers and 3380 // whether the parameter types are references). 3381 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3382 << Name << DC << D.getCXXScopeSpec().getRange(); 3383 NewFD->setInvalidDecl(); 3384 3385 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3386 ForRedeclaration); 3387 LookupQualifiedName(Prev, DC); 3388 assert(!Prev.isAmbiguous() && 3389 "Cannot have an ambiguity in previous-declaration lookup"); 3390 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3391 Func != FuncEnd; ++Func) { 3392 if (isa<FunctionDecl>(*Func) && 3393 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3394 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3395 } 3396 } 3397 } 3398 3399 // Handle attributes. We need to have merged decls when handling attributes 3400 // (for example to check for conflicts, etc). 3401 // FIXME: This needs to happen before we merge declarations. Then, 3402 // let attribute merging cope with attribute conflicts. 3403 ProcessDeclAttributes(S, NewFD, D); 3404 3405 // attributes declared post-definition are currently ignored 3406 if (Redeclaration && Previous.isSingleResult()) { 3407 const FunctionDecl *Def; 3408 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3409 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3410 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3411 Diag(Def->getLocation(), diag::note_previous_definition); 3412 } 3413 } 3414 3415 AddKnownFunctionAttributes(NewFD); 3416 3417 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3418 // If a function name is overloadable in C, then every function 3419 // with that name must be marked "overloadable". 3420 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3421 << Redeclaration << NewFD; 3422 if (!Previous.empty()) 3423 Diag(Previous.getRepresentativeDecl()->getLocation(), 3424 diag::note_attribute_overloadable_prev_overload); 3425 NewFD->addAttr(::new (Context) OverloadableAttr()); 3426 } 3427 3428 // If this is a locally-scoped extern C function, update the 3429 // map of such names. 3430 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3431 && !NewFD->isInvalidDecl()) 3432 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3433 3434 // Set this FunctionDecl's range up to the right paren. 3435 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3436 3437 if (FunctionTemplate && NewFD->isInvalidDecl()) 3438 FunctionTemplate->setInvalidDecl(); 3439 3440 if (FunctionTemplate) 3441 return FunctionTemplate; 3442 3443 return NewFD; 3444} 3445 3446/// \brief Perform semantic checking of a new function declaration. 3447/// 3448/// Performs semantic analysis of the new function declaration 3449/// NewFD. This routine performs all semantic checking that does not 3450/// require the actual declarator involved in the declaration, and is 3451/// used both for the declaration of functions as they are parsed 3452/// (called via ActOnDeclarator) and for the declaration of functions 3453/// that have been instantiated via C++ template instantiation (called 3454/// via InstantiateDecl). 3455/// 3456/// \param IsExplicitSpecialiation whether this new function declaration is 3457/// an explicit specialization of the previous declaration. 3458/// 3459/// This sets NewFD->isInvalidDecl() to true if there was an error. 3460void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3461 LookupResult &Previous, 3462 bool IsExplicitSpecialization, 3463 bool &Redeclaration, 3464 bool &OverloadableAttrRequired) { 3465 // If NewFD is already known erroneous, don't do any of this checking. 3466 if (NewFD->isInvalidDecl()) 3467 return; 3468 3469 if (NewFD->getResultType()->isVariablyModifiedType()) { 3470 // Functions returning a variably modified type violate C99 6.7.5.2p2 3471 // because all functions have linkage. 3472 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3473 return NewFD->setInvalidDecl(); 3474 } 3475 3476 if (NewFD->isMain()) 3477 CheckMain(NewFD); 3478 3479 // Check for a previous declaration of this name. 3480 if (Previous.empty() && NewFD->isExternC()) { 3481 // Since we did not find anything by this name and we're declaring 3482 // an extern "C" function, look for a non-visible extern "C" 3483 // declaration with the same name. 3484 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3485 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3486 if (Pos != LocallyScopedExternalDecls.end()) 3487 Previous.addDecl(Pos->second); 3488 } 3489 3490 // Merge or overload the declaration with an existing declaration of 3491 // the same name, if appropriate. 3492 if (!Previous.empty()) { 3493 // Determine whether NewFD is an overload of PrevDecl or 3494 // a declaration that requires merging. If it's an overload, 3495 // there's no more work to do here; we'll just add the new 3496 // function to the scope. 3497 3498 NamedDecl *OldDecl = 0; 3499 if (!AllowOverloadingOfFunction(Previous, Context)) { 3500 Redeclaration = true; 3501 OldDecl = Previous.getFoundDecl(); 3502 } else { 3503 if (!getLangOptions().CPlusPlus) { 3504 OverloadableAttrRequired = true; 3505 3506 // Functions marked "overloadable" must have a prototype (that 3507 // we can't get through declaration merging). 3508 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3509 Diag(NewFD->getLocation(), 3510 diag::err_attribute_overloadable_no_prototype) 3511 << NewFD; 3512 Redeclaration = true; 3513 3514 // Turn this into a variadic function with no parameters. 3515 QualType R = Context.getFunctionType( 3516 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3517 0, 0, true, 0); 3518 NewFD->setType(R); 3519 return NewFD->setInvalidDecl(); 3520 } 3521 } 3522 3523 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3524 case Ovl_Match: 3525 Redeclaration = true; 3526 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3527 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3528 Redeclaration = false; 3529 } 3530 break; 3531 3532 case Ovl_NonFunction: 3533 Redeclaration = true; 3534 break; 3535 3536 case Ovl_Overload: 3537 Redeclaration = false; 3538 break; 3539 } 3540 } 3541 3542 if (Redeclaration) { 3543 // NewFD and OldDecl represent declarations that need to be 3544 // merged. 3545 if (MergeFunctionDecl(NewFD, OldDecl)) 3546 return NewFD->setInvalidDecl(); 3547 3548 Previous.clear(); 3549 Previous.addDecl(OldDecl); 3550 3551 if (FunctionTemplateDecl *OldTemplateDecl 3552 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3553 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3554 FunctionTemplateDecl *NewTemplateDecl 3555 = NewFD->getDescribedFunctionTemplate(); 3556 assert(NewTemplateDecl && "Template/non-template mismatch"); 3557 if (CXXMethodDecl *Method 3558 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3559 Method->setAccess(OldTemplateDecl->getAccess()); 3560 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3561 } 3562 3563 // If this is an explicit specialization of a member that is a function 3564 // template, mark it as a member specialization. 3565 if (IsExplicitSpecialization && 3566 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3567 NewTemplateDecl->setMemberSpecialization(); 3568 assert(OldTemplateDecl->isMemberSpecialization()); 3569 } 3570 } else { 3571 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3572 NewFD->setAccess(OldDecl->getAccess()); 3573 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3574 } 3575 } 3576 } 3577 3578 // Semantic checking for this function declaration (in isolation). 3579 if (getLangOptions().CPlusPlus) { 3580 // C++-specific checks. 3581 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3582 CheckConstructor(Constructor); 3583 } else if (CXXDestructorDecl *Destructor = 3584 dyn_cast<CXXDestructorDecl>(NewFD)) { 3585 CXXRecordDecl *Record = Destructor->getParent(); 3586 QualType ClassType = Context.getTypeDeclType(Record); 3587 3588 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3589 // type is dependent? Both gcc and edg can handle that. 3590 if (!ClassType->isDependentType()) { 3591 DeclarationName Name 3592 = Context.DeclarationNames.getCXXDestructorName( 3593 Context.getCanonicalType(ClassType)); 3594 if (NewFD->getDeclName() != Name) { 3595 Diag(NewFD->getLocation(), diag::err_destructor_name); 3596 return NewFD->setInvalidDecl(); 3597 } 3598 } 3599 3600 Record->setUserDeclaredDestructor(true); 3601 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3602 // user-defined destructor. 3603 Record->setPOD(false); 3604 3605 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3606 // declared destructor. 3607 // FIXME: C++0x: don't do this for "= default" destructors 3608 Record->setHasTrivialDestructor(false); 3609 } else if (CXXConversionDecl *Conversion 3610 = dyn_cast<CXXConversionDecl>(NewFD)) { 3611 ActOnConversionDeclarator(Conversion); 3612 } 3613 3614 // Find any virtual functions that this function overrides. 3615 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3616 if (!Method->isFunctionTemplateSpecialization() && 3617 !Method->getDescribedFunctionTemplate()) 3618 AddOverriddenMethods(Method->getParent(), Method); 3619 } 3620 3621 // Additional checks for the destructor; make sure we do this after we 3622 // figure out whether the destructor is virtual. 3623 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3624 if (!Destructor->getParent()->isDependentType()) 3625 CheckDestructor(Destructor); 3626 3627 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3628 if (NewFD->isOverloadedOperator() && 3629 CheckOverloadedOperatorDeclaration(NewFD)) 3630 return NewFD->setInvalidDecl(); 3631 3632 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3633 if (NewFD->getLiteralIdentifier() && 3634 CheckLiteralOperatorDeclaration(NewFD)) 3635 return NewFD->setInvalidDecl(); 3636 3637 // In C++, check default arguments now that we have merged decls. Unless 3638 // the lexical context is the class, because in this case this is done 3639 // during delayed parsing anyway. 3640 if (!CurContext->isRecord()) 3641 CheckCXXDefaultArguments(NewFD); 3642 } 3643} 3644 3645void Sema::CheckMain(FunctionDecl* FD) { 3646 // C++ [basic.start.main]p3: A program that declares main to be inline 3647 // or static is ill-formed. 3648 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3649 // shall not appear in a declaration of main. 3650 // static main is not an error under C99, but we should warn about it. 3651 bool isInline = FD->isInlineSpecified(); 3652 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3653 if (isInline || isStatic) { 3654 unsigned diagID = diag::warn_unusual_main_decl; 3655 if (isInline || getLangOptions().CPlusPlus) 3656 diagID = diag::err_unusual_main_decl; 3657 3658 int which = isStatic + (isInline << 1) - 1; 3659 Diag(FD->getLocation(), diagID) << which; 3660 } 3661 3662 QualType T = FD->getType(); 3663 assert(T->isFunctionType() && "function decl is not of function type"); 3664 const FunctionType* FT = T->getAs<FunctionType>(); 3665 3666 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3667 // TODO: add a replacement fixit to turn the return type into 'int'. 3668 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3669 FD->setInvalidDecl(true); 3670 } 3671 3672 // Treat protoless main() as nullary. 3673 if (isa<FunctionNoProtoType>(FT)) return; 3674 3675 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3676 unsigned nparams = FTP->getNumArgs(); 3677 assert(FD->getNumParams() == nparams); 3678 3679 bool HasExtraParameters = (nparams > 3); 3680 3681 // Darwin passes an undocumented fourth argument of type char**. If 3682 // other platforms start sprouting these, the logic below will start 3683 // getting shifty. 3684 if (nparams == 4 && 3685 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3686 HasExtraParameters = false; 3687 3688 if (HasExtraParameters) { 3689 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3690 FD->setInvalidDecl(true); 3691 nparams = 3; 3692 } 3693 3694 // FIXME: a lot of the following diagnostics would be improved 3695 // if we had some location information about types. 3696 3697 QualType CharPP = 3698 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3699 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3700 3701 for (unsigned i = 0; i < nparams; ++i) { 3702 QualType AT = FTP->getArgType(i); 3703 3704 bool mismatch = true; 3705 3706 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3707 mismatch = false; 3708 else if (Expected[i] == CharPP) { 3709 // As an extension, the following forms are okay: 3710 // char const ** 3711 // char const * const * 3712 // char * const * 3713 3714 QualifierCollector qs; 3715 const PointerType* PT; 3716 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3717 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3718 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3719 qs.removeConst(); 3720 mismatch = !qs.empty(); 3721 } 3722 } 3723 3724 if (mismatch) { 3725 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3726 // TODO: suggest replacing given type with expected type 3727 FD->setInvalidDecl(true); 3728 } 3729 } 3730 3731 if (nparams == 1 && !FD->isInvalidDecl()) { 3732 Diag(FD->getLocation(), diag::warn_main_one_arg); 3733 } 3734} 3735 3736bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3737 // FIXME: Need strict checking. In C89, we need to check for 3738 // any assignment, increment, decrement, function-calls, or 3739 // commas outside of a sizeof. In C99, it's the same list, 3740 // except that the aforementioned are allowed in unevaluated 3741 // expressions. Everything else falls under the 3742 // "may accept other forms of constant expressions" exception. 3743 // (We never end up here for C++, so the constant expression 3744 // rules there don't matter.) 3745 if (Init->isConstantInitializer(Context)) 3746 return false; 3747 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3748 << Init->getSourceRange(); 3749 return true; 3750} 3751 3752void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3753 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3754} 3755 3756/// AddInitializerToDecl - Adds the initializer Init to the 3757/// declaration dcl. If DirectInit is true, this is C++ direct 3758/// initialization rather than copy initialization. 3759void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3760 Decl *RealDecl = dcl.getAs<Decl>(); 3761 // If there is no declaration, there was an error parsing it. Just ignore 3762 // the initializer. 3763 if (RealDecl == 0) 3764 return; 3765 3766 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3767 // With declarators parsed the way they are, the parser cannot 3768 // distinguish between a normal initializer and a pure-specifier. 3769 // Thus this grotesque test. 3770 IntegerLiteral *IL; 3771 Expr *Init = static_cast<Expr *>(init.get()); 3772 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3773 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3774 CheckPureMethod(Method, Init->getSourceRange()); 3775 else { 3776 Diag(Method->getLocation(), diag::err_member_function_initialization) 3777 << Method->getDeclName() << Init->getSourceRange(); 3778 Method->setInvalidDecl(); 3779 } 3780 return; 3781 } 3782 3783 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3784 if (!VDecl) { 3785 if (getLangOptions().CPlusPlus && 3786 RealDecl->getLexicalDeclContext()->isRecord() && 3787 isa<NamedDecl>(RealDecl)) 3788 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3789 << cast<NamedDecl>(RealDecl)->getDeclName(); 3790 else 3791 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3792 RealDecl->setInvalidDecl(); 3793 return; 3794 } 3795 3796 // A definition must end up with a complete type, which means it must be 3797 // complete with the restriction that an array type might be completed by the 3798 // initializer; note that later code assumes this restriction. 3799 QualType BaseDeclType = VDecl->getType(); 3800 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3801 BaseDeclType = Array->getElementType(); 3802 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3803 diag::err_typecheck_decl_incomplete_type)) { 3804 RealDecl->setInvalidDecl(); 3805 return; 3806 } 3807 3808 // The variable can not have an abstract class type. 3809 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3810 diag::err_abstract_type_in_decl, 3811 AbstractVariableType)) 3812 VDecl->setInvalidDecl(); 3813 3814 const VarDecl *Def = 0; 3815 if (VDecl->getDefinition(Def)) { 3816 Diag(VDecl->getLocation(), diag::err_redefinition) 3817 << VDecl->getDeclName(); 3818 Diag(Def->getLocation(), diag::note_previous_definition); 3819 VDecl->setInvalidDecl(); 3820 return; 3821 } 3822 3823 // Take ownership of the expression, now that we're sure we have somewhere 3824 // to put it. 3825 Expr *Init = init.takeAs<Expr>(); 3826 assert(Init && "missing initializer"); 3827 3828 // Capture the variable that is being initialized and the style of 3829 // initialization. 3830 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3831 3832 // FIXME: Poor source location information. 3833 InitializationKind Kind 3834 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3835 Init->getLocStart(), 3836 Init->getLocEnd()) 3837 : InitializationKind::CreateCopy(VDecl->getLocation(), 3838 Init->getLocStart()); 3839 3840 // Get the decls type and save a reference for later, since 3841 // CheckInitializerTypes may change it. 3842 QualType DclT = VDecl->getType(), SavT = DclT; 3843 if (VDecl->isBlockVarDecl()) { 3844 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3845 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3846 VDecl->setInvalidDecl(); 3847 } else if (!VDecl->isInvalidDecl()) { 3848 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3849 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3850 MultiExprArg(*this, (void**)&Init, 1), 3851 &DclT); 3852 if (Result.isInvalid()) { 3853 VDecl->setInvalidDecl(); 3854 return; 3855 } 3856 3857 Init = Result.takeAs<Expr>(); 3858 3859 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3860 // Don't check invalid declarations to avoid emitting useless diagnostics. 3861 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3862 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3863 CheckForConstantInitializer(Init, DclT); 3864 } 3865 } 3866 } else if (VDecl->isStaticDataMember() && 3867 VDecl->getLexicalDeclContext()->isRecord()) { 3868 // This is an in-class initialization for a static data member, e.g., 3869 // 3870 // struct S { 3871 // static const int value = 17; 3872 // }; 3873 3874 // Attach the initializer 3875 VDecl->setInit(Context, Init); 3876 3877 // C++ [class.mem]p4: 3878 // A member-declarator can contain a constant-initializer only 3879 // if it declares a static member (9.4) of const integral or 3880 // const enumeration type, see 9.4.2. 3881 QualType T = VDecl->getType(); 3882 if (!T->isDependentType() && 3883 (!Context.getCanonicalType(T).isConstQualified() || 3884 !T->isIntegralType())) { 3885 Diag(VDecl->getLocation(), diag::err_member_initialization) 3886 << VDecl->getDeclName() << Init->getSourceRange(); 3887 VDecl->setInvalidDecl(); 3888 } else { 3889 // C++ [class.static.data]p4: 3890 // If a static data member is of const integral or const 3891 // enumeration type, its declaration in the class definition 3892 // can specify a constant-initializer which shall be an 3893 // integral constant expression (5.19). 3894 if (!Init->isTypeDependent() && 3895 !Init->getType()->isIntegralType()) { 3896 // We have a non-dependent, non-integral or enumeration type. 3897 Diag(Init->getSourceRange().getBegin(), 3898 diag::err_in_class_initializer_non_integral_type) 3899 << Init->getType() << Init->getSourceRange(); 3900 VDecl->setInvalidDecl(); 3901 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3902 // Check whether the expression is a constant expression. 3903 llvm::APSInt Value; 3904 SourceLocation Loc; 3905 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3906 Diag(Loc, diag::err_in_class_initializer_non_constant) 3907 << Init->getSourceRange(); 3908 VDecl->setInvalidDecl(); 3909 } else if (!VDecl->getType()->isDependentType()) 3910 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3911 } 3912 } 3913 } else if (VDecl->isFileVarDecl()) { 3914 if (VDecl->getStorageClass() == VarDecl::Extern) 3915 Diag(VDecl->getLocation(), diag::warn_extern_init); 3916 if (!VDecl->isInvalidDecl()) { 3917 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3918 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3919 MultiExprArg(*this, (void**)&Init, 1), 3920 &DclT); 3921 if (Result.isInvalid()) { 3922 VDecl->setInvalidDecl(); 3923 return; 3924 } 3925 3926 Init = Result.takeAs<Expr>(); 3927 } 3928 3929 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3930 // Don't check invalid declarations to avoid emitting useless diagnostics. 3931 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3932 // C99 6.7.8p4. All file scoped initializers need to be constant. 3933 CheckForConstantInitializer(Init, DclT); 3934 } 3935 } 3936 // If the type changed, it means we had an incomplete type that was 3937 // completed by the initializer. For example: 3938 // int ary[] = { 1, 3, 5 }; 3939 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3940 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3941 VDecl->setType(DclT); 3942 Init->setType(DclT); 3943 } 3944 3945 Init = MaybeCreateCXXExprWithTemporaries(Init); 3946 // Attach the initializer to the decl. 3947 VDecl->setInit(Context, Init); 3948 3949 // If the previous declaration of VDecl was a tentative definition, 3950 // remove it from the set of tentative definitions. 3951 if (VDecl->getPreviousDeclaration() && 3952 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3953 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3954 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3955 } 3956 3957 if (getLangOptions().CPlusPlus) { 3958 // Make sure we mark the destructor as used if necessary. 3959 QualType InitType = VDecl->getType(); 3960 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3961 InitType = Context.getBaseElementType(Array); 3962 if (InitType->isRecordType()) 3963 FinalizeVarWithDestructor(VDecl, InitType); 3964 } 3965 3966 return; 3967} 3968 3969void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3970 bool TypeContainsUndeducedAuto) { 3971 Decl *RealDecl = dcl.getAs<Decl>(); 3972 3973 // If there is no declaration, there was an error parsing it. Just ignore it. 3974 if (RealDecl == 0) 3975 return; 3976 3977 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3978 QualType Type = Var->getType(); 3979 3980 // Record tentative definitions. 3981 if (Var->isTentativeDefinition(Context)) { 3982 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3983 InsertPair = 3984 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3985 3986 // Keep the latest definition in the map. If we see 'int i; int i;' we 3987 // want the second one in the map. 3988 InsertPair.first->second = Var; 3989 3990 // However, for the list, we don't care about the order, just make sure 3991 // that there are no dupes for a given declaration name. 3992 if (InsertPair.second) 3993 TentativeDefinitionList.push_back(Var->getDeclName()); 3994 } 3995 3996 // C++ [dcl.init.ref]p3: 3997 // The initializer can be omitted for a reference only in a 3998 // parameter declaration (8.3.5), in the declaration of a 3999 // function return type, in the declaration of a class member 4000 // within its class declaration (9.2), and where the extern 4001 // specifier is explicitly used. 4002 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 4003 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4004 << Var->getDeclName() 4005 << SourceRange(Var->getLocation(), Var->getLocation()); 4006 Var->setInvalidDecl(); 4007 return; 4008 } 4009 4010 // C++0x [dcl.spec.auto]p3 4011 if (TypeContainsUndeducedAuto) { 4012 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4013 << Var->getDeclName() << Type; 4014 Var->setInvalidDecl(); 4015 return; 4016 } 4017 4018 // An array without size is an incomplete type, and there are no special 4019 // rules in C++ to make such a definition acceptable. 4020 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 4021 !Var->hasExternalStorage()) { 4022 Diag(Var->getLocation(), 4023 diag::err_typecheck_incomplete_array_needs_initializer); 4024 Var->setInvalidDecl(); 4025 return; 4026 } 4027 4028 // C++ [temp.expl.spec]p15: 4029 // An explicit specialization of a static data member of a template is a 4030 // definition if the declaration includes an initializer; otherwise, it 4031 // is a declaration. 4032 if (Var->isStaticDataMember() && 4033 Var->getInstantiatedFromStaticDataMember() && 4034 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 4035 return; 4036 4037 // C++ [dcl.init]p9: 4038 // If no initializer is specified for an object, and the object 4039 // is of (possibly cv-qualified) non-POD class type (or array 4040 // thereof), the object shall be default-initialized; if the 4041 // object is of const-qualified type, the underlying class type 4042 // shall have a user-declared default constructor. 4043 // 4044 // FIXME: Diagnose the "user-declared default constructor" bit. 4045 if (getLangOptions().CPlusPlus) { 4046 QualType InitType = Type; 4047 if (const ArrayType *Array = Context.getAsArrayType(Type)) 4048 InitType = Context.getBaseElementType(Array); 4049 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 4050 InitType->isRecordType() && !InitType->isDependentType()) { 4051 if (!RequireCompleteType(Var->getLocation(), InitType, 4052 diag::err_invalid_incomplete_type_use)) { 4053 InitializedEntity Entity 4054 = InitializedEntity::InitializeVariable(Var); 4055 InitializationKind Kind 4056 = InitializationKind::CreateDefault(Var->getLocation()); 4057 4058 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4059 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4060 MultiExprArg(*this, 0, 0)); 4061 if (Init.isInvalid()) 4062 Var->setInvalidDecl(); 4063 else { 4064 Var->setInit(Context, 4065 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4066 FinalizeVarWithDestructor(Var, InitType); 4067 } 4068 } else { 4069 Var->setInvalidDecl(); 4070 } 4071 } 4072 4073 // The variable can not have an abstract class type. 4074 if (RequireNonAbstractType(Var->getLocation(), Type, 4075 diag::err_abstract_type_in_decl, 4076 AbstractVariableType)) 4077 Var->setInvalidDecl(); 4078 } 4079 4080#if 0 4081 // FIXME: Temporarily disabled because we are not properly parsing 4082 // linkage specifications on declarations, e.g., 4083 // 4084 // extern "C" const CGPoint CGPointerZero; 4085 // 4086 // C++ [dcl.init]p9: 4087 // 4088 // If no initializer is specified for an object, and the 4089 // object is of (possibly cv-qualified) non-POD class type (or 4090 // array thereof), the object shall be default-initialized; if 4091 // the object is of const-qualified type, the underlying class 4092 // type shall have a user-declared default 4093 // constructor. Otherwise, if no initializer is specified for 4094 // an object, the object and its subobjects, if any, have an 4095 // indeterminate initial value; if the object or any of its 4096 // subobjects are of const-qualified type, the program is 4097 // ill-formed. 4098 // 4099 // This isn't technically an error in C, so we don't diagnose it. 4100 // 4101 // FIXME: Actually perform the POD/user-defined default 4102 // constructor check. 4103 if (getLangOptions().CPlusPlus && 4104 Context.getCanonicalType(Type).isConstQualified() && 4105 !Var->hasExternalStorage()) 4106 Diag(Var->getLocation(), diag::err_const_var_requires_init) 4107 << Var->getName() 4108 << SourceRange(Var->getLocation(), Var->getLocation()); 4109#endif 4110 } 4111} 4112 4113Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4114 DeclPtrTy *Group, 4115 unsigned NumDecls) { 4116 llvm::SmallVector<Decl*, 8> Decls; 4117 4118 if (DS.isTypeSpecOwned()) 4119 Decls.push_back((Decl*)DS.getTypeRep()); 4120 4121 for (unsigned i = 0; i != NumDecls; ++i) 4122 if (Decl *D = Group[i].getAs<Decl>()) 4123 Decls.push_back(D); 4124 4125 // Perform semantic analysis that depends on having fully processed both 4126 // the declarator and initializer. 4127 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 4128 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 4129 if (!IDecl) 4130 continue; 4131 QualType T = IDecl->getType(); 4132 4133 // Block scope. C99 6.7p7: If an identifier for an object is declared with 4134 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 4135 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 4136 if (T->isDependentType()) { 4137 // If T is dependent, we should not require a complete type. 4138 // (RequireCompleteType shouldn't be called with dependent types.) 4139 // But we still can at least check if we've got an array of unspecified 4140 // size without an initializer. 4141 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 4142 !IDecl->getInit()) { 4143 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 4144 << T; 4145 IDecl->setInvalidDecl(); 4146 } 4147 } else if (!IDecl->isInvalidDecl()) { 4148 // If T is an incomplete array type with an initializer list that is 4149 // dependent on something, its size has not been fixed. We could attempt 4150 // to fix the size for such arrays, but we would still have to check 4151 // here for initializers containing a C++0x vararg expansion, e.g. 4152 // template <typename... Args> void f(Args... args) { 4153 // int vals[] = { args }; 4154 // } 4155 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 4156 Expr *Init = IDecl->getInit(); 4157 if (IAT && Init && 4158 (Init->isTypeDependent() || Init->isValueDependent())) { 4159 // Check that the member type of the array is complete, at least. 4160 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 4161 diag::err_typecheck_decl_incomplete_type)) 4162 IDecl->setInvalidDecl(); 4163 } else if (RequireCompleteType(IDecl->getLocation(), T, 4164 diag::err_typecheck_decl_incomplete_type)) 4165 IDecl->setInvalidDecl(); 4166 } 4167 } 4168 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4169 // object that has file scope without an initializer, and without a 4170 // storage-class specifier or with the storage-class specifier "static", 4171 // constitutes a tentative definition. Note: A tentative definition with 4172 // external linkage is valid (C99 6.2.2p5). 4173 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 4174 if (const IncompleteArrayType *ArrayT 4175 = Context.getAsIncompleteArrayType(T)) { 4176 if (RequireCompleteType(IDecl->getLocation(), 4177 ArrayT->getElementType(), 4178 diag::err_illegal_decl_array_incomplete_type)) 4179 IDecl->setInvalidDecl(); 4180 } else if (IDecl->getStorageClass() == VarDecl::Static) { 4181 // C99 6.9.2p3: If the declaration of an identifier for an object is 4182 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4183 // declared type shall not be an incomplete type. 4184 // NOTE: code such as the following 4185 // static struct s; 4186 // struct s { int a; }; 4187 // is accepted by gcc. Hence here we issue a warning instead of 4188 // an error and we do not invalidate the static declaration. 4189 // NOTE: to avoid multiple warnings, only check the first declaration. 4190 if (IDecl->getPreviousDeclaration() == 0) 4191 RequireCompleteType(IDecl->getLocation(), T, 4192 diag::ext_typecheck_decl_incomplete_type); 4193 } 4194 } 4195 } 4196 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4197 Decls.data(), Decls.size())); 4198} 4199 4200 4201/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4202/// to introduce parameters into function prototype scope. 4203Sema::DeclPtrTy 4204Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4205 const DeclSpec &DS = D.getDeclSpec(); 4206 4207 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4208 VarDecl::StorageClass StorageClass = VarDecl::None; 4209 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4210 StorageClass = VarDecl::Register; 4211 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4212 Diag(DS.getStorageClassSpecLoc(), 4213 diag::err_invalid_storage_class_in_func_decl); 4214 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4215 } 4216 4217 if (D.getDeclSpec().isThreadSpecified()) 4218 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4219 4220 DiagnoseFunctionSpecifiers(D); 4221 4222 // Check that there are no default arguments inside the type of this 4223 // parameter (C++ only). 4224 if (getLangOptions().CPlusPlus) 4225 CheckExtraCXXDefaultArguments(D); 4226 4227 TypeSourceInfo *TInfo = 0; 4228 TagDecl *OwnedDecl = 0; 4229 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4230 4231 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4232 // C++ [dcl.fct]p6: 4233 // Types shall not be defined in return or parameter types. 4234 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4235 << Context.getTypeDeclType(OwnedDecl); 4236 } 4237 4238 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 4239 // Can this happen for params? We already checked that they don't conflict 4240 // among each other. Here they can only shadow globals, which is ok. 4241 IdentifierInfo *II = D.getIdentifier(); 4242 if (II) { 4243 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 4244 if (PrevDecl->isTemplateParameter()) { 4245 // Maybe we will complain about the shadowed template parameter. 4246 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4247 // Just pretend that we didn't see the previous declaration. 4248 PrevDecl = 0; 4249 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4250 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4251 4252 // Recover by removing the name 4253 II = 0; 4254 D.SetIdentifier(0, D.getIdentifierLoc()); 4255 } 4256 } 4257 } 4258 4259 // Parameters can not be abstract class types. 4260 // For record types, this is done by the AbstractClassUsageDiagnoser once 4261 // the class has been completely parsed. 4262 if (!CurContext->isRecord() && 4263 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4264 diag::err_abstract_type_in_decl, 4265 AbstractParamType)) 4266 D.setInvalidType(true); 4267 4268 QualType T = adjustParameterType(parmDeclType); 4269 4270 ParmVarDecl *New 4271 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 4272 T, TInfo, StorageClass, 0); 4273 4274 if (D.isInvalidType()) 4275 New->setInvalidDecl(); 4276 4277 // Parameter declarators cannot be interface types. All ObjC objects are 4278 // passed by reference. 4279 if (T->isObjCInterfaceType()) { 4280 Diag(D.getIdentifierLoc(), 4281 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4282 New->setInvalidDecl(); 4283 } 4284 4285 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4286 if (D.getCXXScopeSpec().isSet()) { 4287 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4288 << D.getCXXScopeSpec().getRange(); 4289 New->setInvalidDecl(); 4290 } 4291 4292 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4293 // duration shall not be qualified by an address-space qualifier." 4294 // Since all parameters have automatic store duration, they can not have 4295 // an address space. 4296 if (T.getAddressSpace() != 0) { 4297 Diag(D.getIdentifierLoc(), 4298 diag::err_arg_with_address_space); 4299 New->setInvalidDecl(); 4300 } 4301 4302 4303 // Add the parameter declaration into this scope. 4304 S->AddDecl(DeclPtrTy::make(New)); 4305 if (II) 4306 IdResolver.AddDecl(New); 4307 4308 ProcessDeclAttributes(S, New, D); 4309 4310 if (New->hasAttr<BlocksAttr>()) { 4311 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4312 } 4313 return DeclPtrTy::make(New); 4314} 4315 4316void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4317 SourceLocation LocAfterDecls) { 4318 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4319 "Not a function declarator!"); 4320 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4321 4322 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4323 // for a K&R function. 4324 if (!FTI.hasPrototype) { 4325 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4326 --i; 4327 if (FTI.ArgInfo[i].Param == 0) { 4328 llvm::SmallString<256> Code; 4329 llvm::raw_svector_ostream(Code) << " int " 4330 << FTI.ArgInfo[i].Ident->getName() 4331 << ";\n"; 4332 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4333 << FTI.ArgInfo[i].Ident 4334 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4335 4336 // Implicitly declare the argument as type 'int' for lack of a better 4337 // type. 4338 DeclSpec DS; 4339 const char* PrevSpec; // unused 4340 unsigned DiagID; // unused 4341 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4342 PrevSpec, DiagID); 4343 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4344 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4345 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4346 } 4347 } 4348 } 4349} 4350 4351Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4352 Declarator &D) { 4353 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4354 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4355 "Not a function declarator!"); 4356 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4357 4358 if (FTI.hasPrototype) { 4359 // FIXME: Diagnose arguments without names in C. 4360 } 4361 4362 Scope *ParentScope = FnBodyScope->getParent(); 4363 4364 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4365 MultiTemplateParamsArg(*this), 4366 /*IsFunctionDefinition=*/true); 4367 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4368} 4369 4370static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4371 // Don't warn about invalid declarations. 4372 if (FD->isInvalidDecl()) 4373 return false; 4374 4375 // Or declarations that aren't global. 4376 if (!FD->isGlobal()) 4377 return false; 4378 4379 // Don't warn about C++ member functions. 4380 if (isa<CXXMethodDecl>(FD)) 4381 return false; 4382 4383 // Don't warn about 'main'. 4384 if (FD->isMain()) 4385 return false; 4386 4387 // Don't warn about inline functions. 4388 if (FD->isInlineSpecified()) 4389 return false; 4390 4391 // Don't warn about function templates. 4392 if (FD->getDescribedFunctionTemplate()) 4393 return false; 4394 4395 // Don't warn about function template specializations. 4396 if (FD->isFunctionTemplateSpecialization()) 4397 return false; 4398 4399 bool MissingPrototype = true; 4400 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4401 Prev; Prev = Prev->getPreviousDeclaration()) { 4402 // Ignore any declarations that occur in function or method 4403 // scope, because they aren't visible from the header. 4404 if (Prev->getDeclContext()->isFunctionOrMethod()) 4405 continue; 4406 4407 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4408 break; 4409 } 4410 4411 return MissingPrototype; 4412} 4413 4414Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4415 // Clear the last template instantiation error context. 4416 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4417 4418 if (!D) 4419 return D; 4420 FunctionDecl *FD = 0; 4421 4422 if (FunctionTemplateDecl *FunTmpl 4423 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4424 FD = FunTmpl->getTemplatedDecl(); 4425 else 4426 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4427 4428 CurFunctionNeedsScopeChecking = false; 4429 4430 // See if this is a redefinition. 4431 const FunctionDecl *Definition; 4432 if (FD->getBody(Definition)) { 4433 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4434 Diag(Definition->getLocation(), diag::note_previous_definition); 4435 } 4436 4437 // Builtin functions cannot be defined. 4438 if (unsigned BuiltinID = FD->getBuiltinID()) { 4439 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4440 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4441 FD->setInvalidDecl(); 4442 } 4443 } 4444 4445 // The return type of a function definition must be complete 4446 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4447 QualType ResultType = FD->getResultType(); 4448 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4449 !FD->isInvalidDecl() && 4450 RequireCompleteType(FD->getLocation(), ResultType, 4451 diag::err_func_def_incomplete_result)) 4452 FD->setInvalidDecl(); 4453 4454 // GNU warning -Wmissing-prototypes: 4455 // Warn if a global function is defined without a previous 4456 // prototype declaration. This warning is issued even if the 4457 // definition itself provides a prototype. The aim is to detect 4458 // global functions that fail to be declared in header files. 4459 if (ShouldWarnAboutMissingPrototype(FD)) 4460 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4461 4462 if (FnBodyScope) 4463 PushDeclContext(FnBodyScope, FD); 4464 4465 // Check the validity of our function parameters 4466 CheckParmsForFunctionDef(FD); 4467 4468 // Introduce our parameters into the function scope 4469 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4470 ParmVarDecl *Param = FD->getParamDecl(p); 4471 Param->setOwningFunction(FD); 4472 4473 // If this has an identifier, add it to the scope stack. 4474 if (Param->getIdentifier() && FnBodyScope) 4475 PushOnScopeChains(Param, FnBodyScope); 4476 } 4477 4478 // Checking attributes of current function definition 4479 // dllimport attribute. 4480 if (FD->getAttr<DLLImportAttr>() && 4481 (!FD->getAttr<DLLExportAttr>())) { 4482 // dllimport attribute cannot be applied to definition. 4483 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4484 Diag(FD->getLocation(), 4485 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4486 << "dllimport"; 4487 FD->setInvalidDecl(); 4488 return DeclPtrTy::make(FD); 4489 } else { 4490 // If a symbol previously declared dllimport is later defined, the 4491 // attribute is ignored in subsequent references, and a warning is 4492 // emitted. 4493 Diag(FD->getLocation(), 4494 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4495 << FD->getNameAsCString() << "dllimport"; 4496 } 4497 } 4498 return DeclPtrTy::make(FD); 4499} 4500 4501Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4502 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4503} 4504 4505Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4506 bool IsInstantiation) { 4507 Decl *dcl = D.getAs<Decl>(); 4508 Stmt *Body = BodyArg.takeAs<Stmt>(); 4509 4510 AnalysisContext AC(dcl); 4511 FunctionDecl *FD = 0; 4512 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4513 if (FunTmpl) 4514 FD = FunTmpl->getTemplatedDecl(); 4515 else 4516 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4517 4518 if (FD) { 4519 FD->setBody(Body); 4520 if (FD->isMain()) 4521 // C and C++ allow for main to automagically return 0. 4522 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4523 FD->setHasImplicitReturnZero(true); 4524 else 4525 CheckFallThroughForFunctionDef(FD, Body, AC); 4526 4527 if (!FD->isInvalidDecl()) 4528 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4529 4530 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4531 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4532 4533 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4534 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4535 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4536 MD->setBody(Body); 4537 CheckFallThroughForFunctionDef(MD, Body, AC); 4538 MD->setEndLoc(Body->getLocEnd()); 4539 4540 if (!MD->isInvalidDecl()) 4541 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4542 } else { 4543 Body->Destroy(Context); 4544 return DeclPtrTy(); 4545 } 4546 if (!IsInstantiation) 4547 PopDeclContext(); 4548 4549 // Verify and clean out per-function state. 4550 4551 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4552 4553 // Check goto/label use. 4554 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4555 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4556 LabelStmt *L = I->second; 4557 4558 // Verify that we have no forward references left. If so, there was a goto 4559 // or address of a label taken, but no definition of it. Label fwd 4560 // definitions are indicated with a null substmt. 4561 if (L->getSubStmt() != 0) 4562 continue; 4563 4564 // Emit error. 4565 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4566 4567 // At this point, we have gotos that use the bogus label. Stitch it into 4568 // the function body so that they aren't leaked and that the AST is well 4569 // formed. 4570 if (Body == 0) { 4571 // The whole function wasn't parsed correctly, just delete this. 4572 L->Destroy(Context); 4573 continue; 4574 } 4575 4576 // Otherwise, the body is valid: we want to stitch the label decl into the 4577 // function somewhere so that it is properly owned and so that the goto 4578 // has a valid target. Do this by creating a new compound stmt with the 4579 // label in it. 4580 4581 // Give the label a sub-statement. 4582 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4583 4584 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4585 cast<CXXTryStmt>(Body)->getTryBlock() : 4586 cast<CompoundStmt>(Body); 4587 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4588 Elements.push_back(L); 4589 Compound->setStmts(Context, &Elements[0], Elements.size()); 4590 } 4591 FunctionLabelMap.clear(); 4592 4593 if (!Body) return D; 4594 4595 CheckUnreachable(AC); 4596 4597 // Verify that that gotos and switch cases don't jump into scopes illegally. 4598 if (CurFunctionNeedsScopeChecking) 4599 DiagnoseInvalidJumps(Body); 4600 4601 // C++ constructors that have function-try-blocks can't have return 4602 // statements in the handlers of that block. (C++ [except.handle]p14) 4603 // Verify this. 4604 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4605 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4606 4607 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4608 MarkBaseAndMemberDestructorsReferenced(Destructor); 4609 4610 // If any errors have occurred, clear out any temporaries that may have 4611 // been leftover. This ensures that these temporaries won't be picked up for 4612 // deletion in some later function. 4613 if (PP.getDiagnostics().hasErrorOccurred()) 4614 ExprTemporaries.clear(); 4615 4616 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4617 return D; 4618} 4619 4620/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4621/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4622NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4623 IdentifierInfo &II, Scope *S) { 4624 // Before we produce a declaration for an implicitly defined 4625 // function, see whether there was a locally-scoped declaration of 4626 // this name as a function or variable. If so, use that 4627 // (non-visible) declaration, and complain about it. 4628 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4629 = LocallyScopedExternalDecls.find(&II); 4630 if (Pos != LocallyScopedExternalDecls.end()) { 4631 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4632 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4633 return Pos->second; 4634 } 4635 4636 // Extension in C99. Legal in C90, but warn about it. 4637 if (II.getName().startswith("__builtin_")) 4638 Diag(Loc, diag::warn_builtin_unknown) << &II; 4639 else if (getLangOptions().C99) 4640 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4641 else 4642 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4643 4644 // Set a Declarator for the implicit definition: int foo(); 4645 const char *Dummy; 4646 DeclSpec DS; 4647 unsigned DiagID; 4648 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4649 Error = Error; // Silence warning. 4650 assert(!Error && "Error setting up implicit decl!"); 4651 Declarator D(DS, Declarator::BlockContext); 4652 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4653 0, 0, false, SourceLocation(), 4654 false, 0,0,0, Loc, Loc, D), 4655 SourceLocation()); 4656 D.SetIdentifier(&II, Loc); 4657 4658 // Insert this function into translation-unit scope. 4659 4660 DeclContext *PrevDC = CurContext; 4661 CurContext = Context.getTranslationUnitDecl(); 4662 4663 FunctionDecl *FD = 4664 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4665 FD->setImplicit(); 4666 4667 CurContext = PrevDC; 4668 4669 AddKnownFunctionAttributes(FD); 4670 4671 return FD; 4672} 4673 4674/// \brief Adds any function attributes that we know a priori based on 4675/// the declaration of this function. 4676/// 4677/// These attributes can apply both to implicitly-declared builtins 4678/// (like __builtin___printf_chk) or to library-declared functions 4679/// like NSLog or printf. 4680void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4681 if (FD->isInvalidDecl()) 4682 return; 4683 4684 // If this is a built-in function, map its builtin attributes to 4685 // actual attributes. 4686 if (unsigned BuiltinID = FD->getBuiltinID()) { 4687 // Handle printf-formatting attributes. 4688 unsigned FormatIdx; 4689 bool HasVAListArg; 4690 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4691 if (!FD->getAttr<FormatAttr>()) 4692 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4693 HasVAListArg ? 0 : FormatIdx + 2)); 4694 } 4695 4696 // Mark const if we don't care about errno and that is the only 4697 // thing preventing the function from being const. This allows 4698 // IRgen to use LLVM intrinsics for such functions. 4699 if (!getLangOptions().MathErrno && 4700 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4701 if (!FD->getAttr<ConstAttr>()) 4702 FD->addAttr(::new (Context) ConstAttr()); 4703 } 4704 4705 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4706 FD->addAttr(::new (Context) NoReturnAttr()); 4707 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4708 FD->addAttr(::new (Context) NoThrowAttr()); 4709 if (Context.BuiltinInfo.isConst(BuiltinID)) 4710 FD->addAttr(::new (Context) ConstAttr()); 4711 } 4712 4713 IdentifierInfo *Name = FD->getIdentifier(); 4714 if (!Name) 4715 return; 4716 if ((!getLangOptions().CPlusPlus && 4717 FD->getDeclContext()->isTranslationUnit()) || 4718 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4719 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4720 LinkageSpecDecl::lang_c)) { 4721 // Okay: this could be a libc/libm/Objective-C function we know 4722 // about. 4723 } else 4724 return; 4725 4726 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4727 // FIXME: NSLog and NSLogv should be target specific 4728 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4729 // FIXME: We known better than our headers. 4730 const_cast<FormatAttr *>(Format)->setType("printf"); 4731 } else 4732 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4733 Name->isStr("NSLogv") ? 0 : 2)); 4734 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4735 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4736 // target-specific builtins, perhaps? 4737 if (!FD->getAttr<FormatAttr>()) 4738 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4739 Name->isStr("vasprintf") ? 0 : 3)); 4740 } 4741} 4742 4743TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4744 TypeSourceInfo *TInfo) { 4745 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4746 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4747 4748 if (!TInfo) { 4749 assert(D.isInvalidType() && "no declarator info for valid type"); 4750 TInfo = Context.getTrivialTypeSourceInfo(T); 4751 } 4752 4753 // Scope manipulation handled by caller. 4754 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4755 D.getIdentifierLoc(), 4756 D.getIdentifier(), 4757 TInfo); 4758 4759 if (const TagType *TT = T->getAs<TagType>()) { 4760 TagDecl *TD = TT->getDecl(); 4761 4762 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4763 // keep track of the TypedefDecl. 4764 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4765 TD->setTypedefForAnonDecl(NewTD); 4766 } 4767 4768 if (D.isInvalidType()) 4769 NewTD->setInvalidDecl(); 4770 return NewTD; 4771} 4772 4773 4774/// \brief Determine whether a tag with a given kind is acceptable 4775/// as a redeclaration of the given tag declaration. 4776/// 4777/// \returns true if the new tag kind is acceptable, false otherwise. 4778bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4779 TagDecl::TagKind NewTag, 4780 SourceLocation NewTagLoc, 4781 const IdentifierInfo &Name) { 4782 // C++ [dcl.type.elab]p3: 4783 // The class-key or enum keyword present in the 4784 // elaborated-type-specifier shall agree in kind with the 4785 // declaration to which the name in theelaborated-type-specifier 4786 // refers. This rule also applies to the form of 4787 // elaborated-type-specifier that declares a class-name or 4788 // friend class since it can be construed as referring to the 4789 // definition of the class. Thus, in any 4790 // elaborated-type-specifier, the enum keyword shall be used to 4791 // refer to an enumeration (7.2), the union class-keyshall be 4792 // used to refer to a union (clause 9), and either the class or 4793 // struct class-key shall be used to refer to a class (clause 9) 4794 // declared using the class or struct class-key. 4795 TagDecl::TagKind OldTag = Previous->getTagKind(); 4796 if (OldTag == NewTag) 4797 return true; 4798 4799 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4800 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4801 // Warn about the struct/class tag mismatch. 4802 bool isTemplate = false; 4803 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4804 isTemplate = Record->getDescribedClassTemplate(); 4805 4806 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4807 << (NewTag == TagDecl::TK_class) 4808 << isTemplate << &Name 4809 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4810 OldTag == TagDecl::TK_class? "class" : "struct"); 4811 Diag(Previous->getLocation(), diag::note_previous_use); 4812 return true; 4813 } 4814 return false; 4815} 4816 4817/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4818/// former case, Name will be non-null. In the later case, Name will be null. 4819/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4820/// reference/declaration/definition of a tag. 4821Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4822 SourceLocation KWLoc, const CXXScopeSpec &SS, 4823 IdentifierInfo *Name, SourceLocation NameLoc, 4824 AttributeList *Attr, AccessSpecifier AS, 4825 MultiTemplateParamsArg TemplateParameterLists, 4826 bool &OwnedDecl, bool &IsDependent) { 4827 // If this is not a definition, it must have a name. 4828 assert((Name != 0 || TUK == TUK_Definition) && 4829 "Nameless record must be a definition!"); 4830 4831 OwnedDecl = false; 4832 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4833 4834 // FIXME: Check explicit specializations more carefully. 4835 bool isExplicitSpecialization = false; 4836 if (TUK != TUK_Reference) { 4837 if (TemplateParameterList *TemplateParams 4838 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4839 (TemplateParameterList**)TemplateParameterLists.get(), 4840 TemplateParameterLists.size(), 4841 isExplicitSpecialization)) { 4842 if (TemplateParams->size() > 0) { 4843 // This is a declaration or definition of a class template (which may 4844 // be a member of another template). 4845 OwnedDecl = false; 4846 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4847 SS, Name, NameLoc, Attr, 4848 TemplateParams, 4849 AS); 4850 TemplateParameterLists.release(); 4851 return Result.get(); 4852 } else { 4853 // The "template<>" header is extraneous. 4854 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4855 << ElaboratedType::getNameForTagKind(Kind) << Name; 4856 isExplicitSpecialization = true; 4857 } 4858 } 4859 4860 TemplateParameterLists.release(); 4861 } 4862 4863 DeclContext *SearchDC = CurContext; 4864 DeclContext *DC = CurContext; 4865 bool isStdBadAlloc = false; 4866 bool Invalid = false; 4867 4868 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4869 : NotForRedeclaration); 4870 4871 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4872 4873 if (Name && SS.isNotEmpty()) { 4874 // We have a nested-name tag ('struct foo::bar'). 4875 4876 // Check for invalid 'foo::'. 4877 if (SS.isInvalid()) { 4878 Name = 0; 4879 goto CreateNewDecl; 4880 } 4881 4882 // If this is a friend or a reference to a class in a dependent 4883 // context, don't try to make a decl for it. 4884 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4885 DC = computeDeclContext(SS, false); 4886 if (!DC) { 4887 IsDependent = true; 4888 return DeclPtrTy(); 4889 } 4890 } 4891 4892 if (RequireCompleteDeclContext(SS)) 4893 return DeclPtrTy::make((Decl *)0); 4894 4895 DC = computeDeclContext(SS, true); 4896 SearchDC = DC; 4897 // Look-up name inside 'foo::'. 4898 LookupQualifiedName(Previous, DC); 4899 4900 if (Previous.isAmbiguous()) 4901 return DeclPtrTy(); 4902 4903 if (Previous.empty()) { 4904 // Name lookup did not find anything. However, if the 4905 // nested-name-specifier refers to the current instantiation, 4906 // and that current instantiation has any dependent base 4907 // classes, we might find something at instantiation time: treat 4908 // this as a dependent elaborated-type-specifier. 4909 if (Previous.wasNotFoundInCurrentInstantiation()) { 4910 IsDependent = true; 4911 return DeclPtrTy(); 4912 } 4913 4914 // A tag 'foo::bar' must already exist. 4915 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4916 Name = 0; 4917 Invalid = true; 4918 goto CreateNewDecl; 4919 } 4920 } else if (Name) { 4921 // If this is a named struct, check to see if there was a previous forward 4922 // declaration or definition. 4923 // FIXME: We're looking into outer scopes here, even when we 4924 // shouldn't be. Doing so can result in ambiguities that we 4925 // shouldn't be diagnosing. 4926 LookupName(Previous, S); 4927 4928 // Note: there used to be some attempt at recovery here. 4929 if (Previous.isAmbiguous()) 4930 return DeclPtrTy(); 4931 4932 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4933 // FIXME: This makes sure that we ignore the contexts associated 4934 // with C structs, unions, and enums when looking for a matching 4935 // tag declaration or definition. See the similar lookup tweak 4936 // in Sema::LookupName; is there a better way to deal with this? 4937 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4938 SearchDC = SearchDC->getParent(); 4939 } 4940 } 4941 4942 if (Previous.isSingleResult() && 4943 Previous.getFoundDecl()->isTemplateParameter()) { 4944 // Maybe we will complain about the shadowed template parameter. 4945 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4946 // Just pretend that we didn't see the previous declaration. 4947 Previous.clear(); 4948 } 4949 4950 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4951 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4952 // This is a declaration of or a reference to "std::bad_alloc". 4953 isStdBadAlloc = true; 4954 4955 if (Previous.empty() && StdBadAlloc) { 4956 // std::bad_alloc has been implicitly declared (but made invisible to 4957 // name lookup). Fill in this implicit declaration as the previous 4958 // declaration, so that the declarations get chained appropriately. 4959 Previous.addDecl(StdBadAlloc); 4960 } 4961 } 4962 4963 if (!Previous.empty()) { 4964 assert(Previous.isSingleResult()); 4965 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4966 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4967 // If this is a use of a previous tag, or if the tag is already declared 4968 // in the same scope (so that the definition/declaration completes or 4969 // rementions the tag), reuse the decl. 4970 if (TUK == TUK_Reference || TUK == TUK_Friend || 4971 isDeclInScope(PrevDecl, SearchDC, S)) { 4972 // Make sure that this wasn't declared as an enum and now used as a 4973 // struct or something similar. 4974 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4975 bool SafeToContinue 4976 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4977 Kind != TagDecl::TK_enum); 4978 if (SafeToContinue) 4979 Diag(KWLoc, diag::err_use_with_wrong_tag) 4980 << Name 4981 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4982 PrevTagDecl->getKindName()); 4983 else 4984 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4985 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4986 4987 if (SafeToContinue) 4988 Kind = PrevTagDecl->getTagKind(); 4989 else { 4990 // Recover by making this an anonymous redefinition. 4991 Name = 0; 4992 Previous.clear(); 4993 Invalid = true; 4994 } 4995 } 4996 4997 if (!Invalid) { 4998 // If this is a use, just return the declaration we found. 4999 5000 // FIXME: In the future, return a variant or some other clue 5001 // for the consumer of this Decl to know it doesn't own it. 5002 // For our current ASTs this shouldn't be a problem, but will 5003 // need to be changed with DeclGroups. 5004 if (TUK == TUK_Reference || TUK == TUK_Friend) 5005 return DeclPtrTy::make(PrevTagDecl); 5006 5007 // Diagnose attempts to redefine a tag. 5008 if (TUK == TUK_Definition) { 5009 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 5010 // If we're defining a specialization and the previous definition 5011 // is from an implicit instantiation, don't emit an error 5012 // here; we'll catch this in the general case below. 5013 if (!isExplicitSpecialization || 5014 !isa<CXXRecordDecl>(Def) || 5015 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5016 == TSK_ExplicitSpecialization) { 5017 Diag(NameLoc, diag::err_redefinition) << Name; 5018 Diag(Def->getLocation(), diag::note_previous_definition); 5019 // If this is a redefinition, recover by making this 5020 // struct be anonymous, which will make any later 5021 // references get the previous definition. 5022 Name = 0; 5023 Previous.clear(); 5024 Invalid = true; 5025 } 5026 } else { 5027 // If the type is currently being defined, complain 5028 // about a nested redefinition. 5029 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5030 if (Tag->isBeingDefined()) { 5031 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5032 Diag(PrevTagDecl->getLocation(), 5033 diag::note_previous_definition); 5034 Name = 0; 5035 Previous.clear(); 5036 Invalid = true; 5037 } 5038 } 5039 5040 // Okay, this is definition of a previously declared or referenced 5041 // tag PrevDecl. We're going to create a new Decl for it. 5042 } 5043 } 5044 // If we get here we have (another) forward declaration or we 5045 // have a definition. Just create a new decl. 5046 5047 } else { 5048 // If we get here, this is a definition of a new tag type in a nested 5049 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5050 // new decl/type. We set PrevDecl to NULL so that the entities 5051 // have distinct types. 5052 Previous.clear(); 5053 } 5054 // If we get here, we're going to create a new Decl. If PrevDecl 5055 // is non-NULL, it's a definition of the tag declared by 5056 // PrevDecl. If it's NULL, we have a new definition. 5057 } else { 5058 // PrevDecl is a namespace, template, or anything else 5059 // that lives in the IDNS_Tag identifier namespace. 5060 if (isDeclInScope(PrevDecl, SearchDC, S)) { 5061 // The tag name clashes with a namespace name, issue an error and 5062 // recover by making this tag be anonymous. 5063 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5064 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5065 Name = 0; 5066 Previous.clear(); 5067 Invalid = true; 5068 } else { 5069 // The existing declaration isn't relevant to us; we're in a 5070 // new scope, so clear out the previous declaration. 5071 Previous.clear(); 5072 } 5073 } 5074 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 5075 // C++ [basic.scope.pdecl]p5: 5076 // -- for an elaborated-type-specifier of the form 5077 // 5078 // class-key identifier 5079 // 5080 // if the elaborated-type-specifier is used in the 5081 // decl-specifier-seq or parameter-declaration-clause of a 5082 // function defined in namespace scope, the identifier is 5083 // declared as a class-name in the namespace that contains 5084 // the declaration; otherwise, except as a friend 5085 // declaration, the identifier is declared in the smallest 5086 // non-class, non-function-prototype scope that contains the 5087 // declaration. 5088 // 5089 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5090 // C structs and unions. 5091 // 5092 // It is an error in C++ to declare (rather than define) an enum 5093 // type, including via an elaborated type specifier. We'll 5094 // diagnose that later; for now, declare the enum in the same 5095 // scope as we would have picked for any other tag type. 5096 // 5097 // GNU C also supports this behavior as part of its incomplete 5098 // enum types extension, while GNU C++ does not. 5099 // 5100 // Find the context where we'll be declaring the tag. 5101 // FIXME: We would like to maintain the current DeclContext as the 5102 // lexical context, 5103 while (SearchDC->isRecord()) 5104 SearchDC = SearchDC->getParent(); 5105 5106 // Find the scope where we'll be declaring the tag. 5107 while (S->isClassScope() || 5108 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 5109 ((S->getFlags() & Scope::DeclScope) == 0) || 5110 (S->getEntity() && 5111 ((DeclContext *)S->getEntity())->isTransparentContext())) 5112 S = S->getParent(); 5113 5114 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 5115 // C++ [namespace.memdef]p3: 5116 // If a friend declaration in a non-local class first declares a 5117 // class or function, the friend class or function is a member of 5118 // the innermost enclosing namespace. 5119 while (!SearchDC->isFileContext()) 5120 SearchDC = SearchDC->getParent(); 5121 5122 // The entity of a decl scope is a DeclContext; see PushDeclContext. 5123 while (S->getEntity() != SearchDC) 5124 S = S->getParent(); 5125 } 5126 5127CreateNewDecl: 5128 5129 TagDecl *PrevDecl = 0; 5130 if (Previous.isSingleResult()) 5131 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5132 5133 // If there is an identifier, use the location of the identifier as the 5134 // location of the decl, otherwise use the location of the struct/union 5135 // keyword. 5136 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5137 5138 // Otherwise, create a new declaration. If there is a previous 5139 // declaration of the same entity, the two will be linked via 5140 // PrevDecl. 5141 TagDecl *New; 5142 5143 if (Kind == TagDecl::TK_enum) { 5144 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5145 // enum X { A, B, C } D; D should chain to X. 5146 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5147 cast_or_null<EnumDecl>(PrevDecl)); 5148 // If this is an undefined enum, warn. 5149 if (TUK != TUK_Definition && !Invalid) { 5150 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5151 : diag::ext_forward_ref_enum; 5152 Diag(Loc, DK); 5153 } 5154 } else { 5155 // struct/union/class 5156 5157 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5158 // struct X { int A; } D; D should chain to X. 5159 if (getLangOptions().CPlusPlus) { 5160 // FIXME: Look for a way to use RecordDecl for simple structs. 5161 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5162 cast_or_null<CXXRecordDecl>(PrevDecl)); 5163 5164 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5165 StdBadAlloc = cast<CXXRecordDecl>(New); 5166 } else 5167 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5168 cast_or_null<RecordDecl>(PrevDecl)); 5169 } 5170 5171 if (Kind != TagDecl::TK_enum) { 5172 // Handle #pragma pack: if the #pragma pack stack has non-default 5173 // alignment, make up a packed attribute for this decl. These 5174 // attributes are checked when the ASTContext lays out the 5175 // structure. 5176 // 5177 // It is important for implementing the correct semantics that this 5178 // happen here (in act on tag decl). The #pragma pack stack is 5179 // maintained as a result of parser callbacks which can occur at 5180 // many points during the parsing of a struct declaration (because 5181 // the #pragma tokens are effectively skipped over during the 5182 // parsing of the struct). 5183 if (unsigned Alignment = getPragmaPackAlignment()) 5184 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5185 } 5186 5187 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5188 // C++ [dcl.typedef]p3: 5189 // [...] Similarly, in a given scope, a class or enumeration 5190 // shall not be declared with the same name as a typedef-name 5191 // that is declared in that scope and refers to a type other 5192 // than the class or enumeration itself. 5193 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5194 ForRedeclaration); 5195 LookupName(Lookup, S); 5196 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5197 NamedDecl *PrevTypedefNamed = PrevTypedef; 5198 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5199 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5200 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5201 Diag(Loc, diag::err_tag_definition_of_typedef) 5202 << Context.getTypeDeclType(New) 5203 << PrevTypedef->getUnderlyingType(); 5204 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5205 Invalid = true; 5206 } 5207 } 5208 5209 // If this is a specialization of a member class (of a class template), 5210 // check the specialization. 5211 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5212 Invalid = true; 5213 5214 if (Invalid) 5215 New->setInvalidDecl(); 5216 5217 if (Attr) 5218 ProcessDeclAttributeList(S, New, Attr); 5219 5220 // If we're declaring or defining a tag in function prototype scope 5221 // in C, note that this type can only be used within the function. 5222 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5223 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5224 5225 // Set the lexical context. If the tag has a C++ scope specifier, the 5226 // lexical context will be different from the semantic context. 5227 New->setLexicalDeclContext(CurContext); 5228 5229 // Mark this as a friend decl if applicable. 5230 if (TUK == TUK_Friend) 5231 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5232 5233 // Set the access specifier. 5234 if (!Invalid && TUK != TUK_Friend) 5235 SetMemberAccessSpecifier(New, PrevDecl, AS); 5236 5237 if (TUK == TUK_Definition) 5238 New->startDefinition(); 5239 5240 // If this has an identifier, add it to the scope stack. 5241 if (TUK == TUK_Friend) { 5242 // We might be replacing an existing declaration in the lookup tables; 5243 // if so, borrow its access specifier. 5244 if (PrevDecl) 5245 New->setAccess(PrevDecl->getAccess()); 5246 5247 // Friend tag decls are visible in fairly strange ways. 5248 if (!CurContext->isDependentContext()) { 5249 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5250 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5251 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5252 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5253 } 5254 } else if (Name) { 5255 S = getNonFieldDeclScope(S); 5256 PushOnScopeChains(New, S); 5257 } else { 5258 CurContext->addDecl(New); 5259 } 5260 5261 // If this is the C FILE type, notify the AST context. 5262 if (IdentifierInfo *II = New->getIdentifier()) 5263 if (!New->isInvalidDecl() && 5264 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5265 II->isStr("FILE")) 5266 Context.setFILEDecl(New); 5267 5268 OwnedDecl = true; 5269 return DeclPtrTy::make(New); 5270} 5271 5272void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5273 AdjustDeclIfTemplate(TagD); 5274 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5275 5276 // Enter the tag context. 5277 PushDeclContext(S, Tag); 5278} 5279 5280void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5281 SourceLocation LBraceLoc) { 5282 AdjustDeclIfTemplate(TagD); 5283 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5284 5285 FieldCollector->StartClass(); 5286 5287 if (!Record->getIdentifier()) 5288 return; 5289 5290 // C++ [class]p2: 5291 // [...] The class-name is also inserted into the scope of the 5292 // class itself; this is known as the injected-class-name. For 5293 // purposes of access checking, the injected-class-name is treated 5294 // as if it were a public member name. 5295 CXXRecordDecl *InjectedClassName 5296 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5297 CurContext, Record->getLocation(), 5298 Record->getIdentifier(), 5299 Record->getTagKeywordLoc(), 5300 Record); 5301 InjectedClassName->setImplicit(); 5302 InjectedClassName->setAccess(AS_public); 5303 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5304 InjectedClassName->setDescribedClassTemplate(Template); 5305 PushOnScopeChains(InjectedClassName, S); 5306 assert(InjectedClassName->isInjectedClassName() && 5307 "Broken injected-class-name"); 5308} 5309 5310// Traverses the class and any nested classes, making a note of any 5311// dynamic classes that have no key function so that we can mark all of 5312// their virtual member functions as "used" at the end of the translation 5313// unit. This ensures that all functions needed by the vtable will get 5314// instantiated/synthesized. 5315static void 5316RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5317 SourceLocation Loc) { 5318 // We don't look at dependent or undefined classes. 5319 if (Record->isDependentContext() || !Record->isDefinition()) 5320 return; 5321 5322 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 5323 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 5324 5325 for (DeclContext::decl_iterator D = Record->decls_begin(), 5326 DEnd = Record->decls_end(); 5327 D != DEnd; ++D) { 5328 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5329 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5330 } 5331} 5332 5333void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5334 SourceLocation RBraceLoc) { 5335 AdjustDeclIfTemplate(TagD); 5336 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5337 Tag->setRBraceLoc(RBraceLoc); 5338 5339 if (isa<CXXRecordDecl>(Tag)) 5340 FieldCollector->FinishClass(); 5341 5342 // Exit this scope of this tag's definition. 5343 PopDeclContext(); 5344 5345 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 5346 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5347 RBraceLoc); 5348 5349 // Notify the consumer that we've defined a tag. 5350 Consumer.HandleTagDeclDefinition(Tag); 5351} 5352 5353// Note that FieldName may be null for anonymous bitfields. 5354bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5355 QualType FieldTy, const Expr *BitWidth, 5356 bool *ZeroWidth) { 5357 // Default to true; that shouldn't confuse checks for emptiness 5358 if (ZeroWidth) 5359 *ZeroWidth = true; 5360 5361 // C99 6.7.2.1p4 - verify the field type. 5362 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5363 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5364 // Handle incomplete types with specific error. 5365 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5366 return true; 5367 if (FieldName) 5368 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5369 << FieldName << FieldTy << BitWidth->getSourceRange(); 5370 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5371 << FieldTy << BitWidth->getSourceRange(); 5372 } 5373 5374 // If the bit-width is type- or value-dependent, don't try to check 5375 // it now. 5376 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5377 return false; 5378 5379 llvm::APSInt Value; 5380 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5381 return true; 5382 5383 if (Value != 0 && ZeroWidth) 5384 *ZeroWidth = false; 5385 5386 // Zero-width bitfield is ok for anonymous field. 5387 if (Value == 0 && FieldName) 5388 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5389 5390 if (Value.isSigned() && Value.isNegative()) { 5391 if (FieldName) 5392 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5393 << FieldName << Value.toString(10); 5394 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5395 << Value.toString(10); 5396 } 5397 5398 if (!FieldTy->isDependentType()) { 5399 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5400 if (Value.getZExtValue() > TypeSize) { 5401 if (FieldName) 5402 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5403 << FieldName << (unsigned)TypeSize; 5404 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5405 << (unsigned)TypeSize; 5406 } 5407 } 5408 5409 return false; 5410} 5411 5412/// ActOnField - Each field of a struct/union/class is passed into this in order 5413/// to create a FieldDecl object for it. 5414Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5415 SourceLocation DeclStart, 5416 Declarator &D, ExprTy *BitfieldWidth) { 5417 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5418 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5419 AS_public); 5420 return DeclPtrTy::make(Res); 5421} 5422 5423/// HandleField - Analyze a field of a C struct or a C++ data member. 5424/// 5425FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5426 SourceLocation DeclStart, 5427 Declarator &D, Expr *BitWidth, 5428 AccessSpecifier AS) { 5429 IdentifierInfo *II = D.getIdentifier(); 5430 SourceLocation Loc = DeclStart; 5431 if (II) Loc = D.getIdentifierLoc(); 5432 5433 TypeSourceInfo *TInfo = 0; 5434 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5435 if (getLangOptions().CPlusPlus) 5436 CheckExtraCXXDefaultArguments(D); 5437 5438 DiagnoseFunctionSpecifiers(D); 5439 5440 if (D.getDeclSpec().isThreadSpecified()) 5441 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5442 5443 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5444 ForRedeclaration); 5445 5446 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5447 // Maybe we will complain about the shadowed template parameter. 5448 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5449 // Just pretend that we didn't see the previous declaration. 5450 PrevDecl = 0; 5451 } 5452 5453 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5454 PrevDecl = 0; 5455 5456 bool Mutable 5457 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5458 SourceLocation TSSL = D.getSourceRange().getBegin(); 5459 FieldDecl *NewFD 5460 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5461 AS, PrevDecl, &D); 5462 if (NewFD->isInvalidDecl() && PrevDecl) { 5463 // Don't introduce NewFD into scope; there's already something 5464 // with the same name in the same scope. 5465 } else if (II) { 5466 PushOnScopeChains(NewFD, S); 5467 } else 5468 Record->addDecl(NewFD); 5469 5470 return NewFD; 5471} 5472 5473/// \brief Build a new FieldDecl and check its well-formedness. 5474/// 5475/// This routine builds a new FieldDecl given the fields name, type, 5476/// record, etc. \p PrevDecl should refer to any previous declaration 5477/// with the same name and in the same scope as the field to be 5478/// created. 5479/// 5480/// \returns a new FieldDecl. 5481/// 5482/// \todo The Declarator argument is a hack. It will be removed once 5483FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5484 TypeSourceInfo *TInfo, 5485 RecordDecl *Record, SourceLocation Loc, 5486 bool Mutable, Expr *BitWidth, 5487 SourceLocation TSSL, 5488 AccessSpecifier AS, NamedDecl *PrevDecl, 5489 Declarator *D) { 5490 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5491 bool InvalidDecl = false; 5492 if (D) InvalidDecl = D->isInvalidType(); 5493 5494 // If we receive a broken type, recover by assuming 'int' and 5495 // marking this declaration as invalid. 5496 if (T.isNull()) { 5497 InvalidDecl = true; 5498 T = Context.IntTy; 5499 } 5500 5501 QualType EltTy = Context.getBaseElementType(T); 5502 if (!EltTy->isDependentType() && 5503 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5504 InvalidDecl = true; 5505 5506 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5507 // than a variably modified type. 5508 if (!InvalidDecl && T->isVariablyModifiedType()) { 5509 bool SizeIsNegative; 5510 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5511 SizeIsNegative); 5512 if (!FixedTy.isNull()) { 5513 Diag(Loc, diag::warn_illegal_constant_array_size); 5514 T = FixedTy; 5515 } else { 5516 if (SizeIsNegative) 5517 Diag(Loc, diag::err_typecheck_negative_array_size); 5518 else 5519 Diag(Loc, diag::err_typecheck_field_variable_size); 5520 InvalidDecl = true; 5521 } 5522 } 5523 5524 // Fields can not have abstract class types 5525 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5526 diag::err_abstract_type_in_decl, 5527 AbstractFieldType)) 5528 InvalidDecl = true; 5529 5530 bool ZeroWidth = false; 5531 // If this is declared as a bit-field, check the bit-field. 5532 if (!InvalidDecl && BitWidth && 5533 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5534 InvalidDecl = true; 5535 DeleteExpr(BitWidth); 5536 BitWidth = 0; 5537 ZeroWidth = false; 5538 } 5539 5540 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5541 BitWidth, Mutable); 5542 if (InvalidDecl) 5543 NewFD->setInvalidDecl(); 5544 5545 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5546 Diag(Loc, diag::err_duplicate_member) << II; 5547 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5548 NewFD->setInvalidDecl(); 5549 } 5550 5551 if (getLangOptions().CPlusPlus) { 5552 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5553 5554 if (!T->isPODType()) 5555 CXXRecord->setPOD(false); 5556 if (!ZeroWidth) 5557 CXXRecord->setEmpty(false); 5558 5559 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5560 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5561 5562 if (!RDecl->hasTrivialConstructor()) 5563 CXXRecord->setHasTrivialConstructor(false); 5564 if (!RDecl->hasTrivialCopyConstructor()) 5565 CXXRecord->setHasTrivialCopyConstructor(false); 5566 if (!RDecl->hasTrivialCopyAssignment()) 5567 CXXRecord->setHasTrivialCopyAssignment(false); 5568 if (!RDecl->hasTrivialDestructor()) 5569 CXXRecord->setHasTrivialDestructor(false); 5570 5571 // C++ 9.5p1: An object of a class with a non-trivial 5572 // constructor, a non-trivial copy constructor, a non-trivial 5573 // destructor, or a non-trivial copy assignment operator 5574 // cannot be a member of a union, nor can an array of such 5575 // objects. 5576 // TODO: C++0x alters this restriction significantly. 5577 if (Record->isUnion()) { 5578 // We check for copy constructors before constructors 5579 // because otherwise we'll never get complaints about 5580 // copy constructors. 5581 5582 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5583 5584 CXXSpecialMember member; 5585 if (!RDecl->hasTrivialCopyConstructor()) 5586 member = CXXCopyConstructor; 5587 else if (!RDecl->hasTrivialConstructor()) 5588 member = CXXDefaultConstructor; 5589 else if (!RDecl->hasTrivialCopyAssignment()) 5590 member = CXXCopyAssignment; 5591 else if (!RDecl->hasTrivialDestructor()) 5592 member = CXXDestructor; 5593 else 5594 member = invalid; 5595 5596 if (member != invalid) { 5597 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5598 DiagnoseNontrivial(RT, member); 5599 NewFD->setInvalidDecl(); 5600 } 5601 } 5602 } 5603 } 5604 5605 // FIXME: We need to pass in the attributes given an AST 5606 // representation, not a parser representation. 5607 if (D) 5608 // FIXME: What to pass instead of TUScope? 5609 ProcessDeclAttributes(TUScope, NewFD, *D); 5610 5611 if (T.isObjCGCWeak()) 5612 Diag(Loc, diag::warn_attribute_weak_on_field); 5613 5614 NewFD->setAccess(AS); 5615 5616 // C++ [dcl.init.aggr]p1: 5617 // An aggregate is an array or a class (clause 9) with [...] no 5618 // private or protected non-static data members (clause 11). 5619 // A POD must be an aggregate. 5620 if (getLangOptions().CPlusPlus && 5621 (AS == AS_private || AS == AS_protected)) { 5622 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5623 CXXRecord->setAggregate(false); 5624 CXXRecord->setPOD(false); 5625 } 5626 5627 return NewFD; 5628} 5629 5630/// DiagnoseNontrivial - Given that a class has a non-trivial 5631/// special member, figure out why. 5632void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5633 QualType QT(T, 0U); 5634 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5635 5636 // Check whether the member was user-declared. 5637 switch (member) { 5638 case CXXDefaultConstructor: 5639 if (RD->hasUserDeclaredConstructor()) { 5640 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5641 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5642 const FunctionDecl *body = 0; 5643 ci->getBody(body); 5644 if (!body || 5645 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5646 SourceLocation CtorLoc = ci->getLocation(); 5647 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5648 return; 5649 } 5650 } 5651 5652 assert(0 && "found no user-declared constructors"); 5653 return; 5654 } 5655 break; 5656 5657 case CXXCopyConstructor: 5658 if (RD->hasUserDeclaredCopyConstructor()) { 5659 SourceLocation CtorLoc = 5660 RD->getCopyConstructor(Context, 0)->getLocation(); 5661 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5662 return; 5663 } 5664 break; 5665 5666 case CXXCopyAssignment: 5667 if (RD->hasUserDeclaredCopyAssignment()) { 5668 // FIXME: this should use the location of the copy 5669 // assignment, not the type. 5670 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5671 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5672 return; 5673 } 5674 break; 5675 5676 case CXXDestructor: 5677 if (RD->hasUserDeclaredDestructor()) { 5678 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5679 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5680 return; 5681 } 5682 break; 5683 } 5684 5685 typedef CXXRecordDecl::base_class_iterator base_iter; 5686 5687 // Virtual bases and members inhibit trivial copying/construction, 5688 // but not trivial destruction. 5689 if (member != CXXDestructor) { 5690 // Check for virtual bases. vbases includes indirect virtual bases, 5691 // so we just iterate through the direct bases. 5692 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5693 if (bi->isVirtual()) { 5694 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5695 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5696 return; 5697 } 5698 5699 // Check for virtual methods. 5700 typedef CXXRecordDecl::method_iterator meth_iter; 5701 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5702 ++mi) { 5703 if (mi->isVirtual()) { 5704 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5705 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5706 return; 5707 } 5708 } 5709 } 5710 5711 bool (CXXRecordDecl::*hasTrivial)() const; 5712 switch (member) { 5713 case CXXDefaultConstructor: 5714 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5715 case CXXCopyConstructor: 5716 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5717 case CXXCopyAssignment: 5718 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5719 case CXXDestructor: 5720 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5721 default: 5722 assert(0 && "unexpected special member"); return; 5723 } 5724 5725 // Check for nontrivial bases (and recurse). 5726 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5727 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5728 assert(BaseRT && "Don't know how to handle dependent bases"); 5729 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5730 if (!(BaseRecTy->*hasTrivial)()) { 5731 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5732 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5733 DiagnoseNontrivial(BaseRT, member); 5734 return; 5735 } 5736 } 5737 5738 // Check for nontrivial members (and recurse). 5739 typedef RecordDecl::field_iterator field_iter; 5740 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5741 ++fi) { 5742 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5743 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5744 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5745 5746 if (!(EltRD->*hasTrivial)()) { 5747 SourceLocation FLoc = (*fi)->getLocation(); 5748 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5749 DiagnoseNontrivial(EltRT, member); 5750 return; 5751 } 5752 } 5753 } 5754 5755 assert(0 && "found no explanation for non-trivial member"); 5756} 5757 5758/// TranslateIvarVisibility - Translate visibility from a token ID to an 5759/// AST enum value. 5760static ObjCIvarDecl::AccessControl 5761TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5762 switch (ivarVisibility) { 5763 default: assert(0 && "Unknown visitibility kind"); 5764 case tok::objc_private: return ObjCIvarDecl::Private; 5765 case tok::objc_public: return ObjCIvarDecl::Public; 5766 case tok::objc_protected: return ObjCIvarDecl::Protected; 5767 case tok::objc_package: return ObjCIvarDecl::Package; 5768 } 5769} 5770 5771/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5772/// in order to create an IvarDecl object for it. 5773Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5774 SourceLocation DeclStart, 5775 DeclPtrTy IntfDecl, 5776 Declarator &D, ExprTy *BitfieldWidth, 5777 tok::ObjCKeywordKind Visibility) { 5778 5779 IdentifierInfo *II = D.getIdentifier(); 5780 Expr *BitWidth = (Expr*)BitfieldWidth; 5781 SourceLocation Loc = DeclStart; 5782 if (II) Loc = D.getIdentifierLoc(); 5783 5784 // FIXME: Unnamed fields can be handled in various different ways, for 5785 // example, unnamed unions inject all members into the struct namespace! 5786 5787 TypeSourceInfo *TInfo = 0; 5788 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5789 5790 if (BitWidth) { 5791 // 6.7.2.1p3, 6.7.2.1p4 5792 if (VerifyBitField(Loc, II, T, BitWidth)) { 5793 D.setInvalidType(); 5794 DeleteExpr(BitWidth); 5795 BitWidth = 0; 5796 } 5797 } else { 5798 // Not a bitfield. 5799 5800 // validate II. 5801 5802 } 5803 5804 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5805 // than a variably modified type. 5806 if (T->isVariablyModifiedType()) { 5807 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5808 D.setInvalidType(); 5809 } 5810 5811 // Get the visibility (access control) for this ivar. 5812 ObjCIvarDecl::AccessControl ac = 5813 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5814 : ObjCIvarDecl::None; 5815 // Must set ivar's DeclContext to its enclosing interface. 5816 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5817 DeclContext *EnclosingContext; 5818 if (ObjCImplementationDecl *IMPDecl = 5819 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5820 // Case of ivar declared in an implementation. Context is that of its class. 5821 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5822 assert(IDecl && "No class- ActOnIvar"); 5823 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5824 } else 5825 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5826 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5827 5828 // Construct the decl. 5829 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5830 EnclosingContext, Loc, II, T, 5831 TInfo, ac, (Expr *)BitfieldWidth); 5832 5833 if (II) { 5834 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5835 ForRedeclaration); 5836 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5837 && !isa<TagDecl>(PrevDecl)) { 5838 Diag(Loc, diag::err_duplicate_member) << II; 5839 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5840 NewID->setInvalidDecl(); 5841 } 5842 } 5843 5844 // Process attributes attached to the ivar. 5845 ProcessDeclAttributes(S, NewID, D); 5846 5847 if (D.isInvalidType()) 5848 NewID->setInvalidDecl(); 5849 5850 if (II) { 5851 // FIXME: When interfaces are DeclContexts, we'll need to add 5852 // these to the interface. 5853 S->AddDecl(DeclPtrTy::make(NewID)); 5854 IdResolver.AddDecl(NewID); 5855 } 5856 5857 return DeclPtrTy::make(NewID); 5858} 5859 5860void Sema::ActOnFields(Scope* S, 5861 SourceLocation RecLoc, DeclPtrTy RecDecl, 5862 DeclPtrTy *Fields, unsigned NumFields, 5863 SourceLocation LBrac, SourceLocation RBrac, 5864 AttributeList *Attr) { 5865 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5866 assert(EnclosingDecl && "missing record or interface decl"); 5867 5868 // If the decl this is being inserted into is invalid, then it may be a 5869 // redeclaration or some other bogus case. Don't try to add fields to it. 5870 if (EnclosingDecl->isInvalidDecl()) { 5871 // FIXME: Deallocate fields? 5872 return; 5873 } 5874 5875 5876 // Verify that all the fields are okay. 5877 unsigned NumNamedMembers = 0; 5878 llvm::SmallVector<FieldDecl*, 32> RecFields; 5879 5880 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5881 for (unsigned i = 0; i != NumFields; ++i) { 5882 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5883 5884 // Get the type for the field. 5885 Type *FDTy = FD->getType().getTypePtr(); 5886 5887 if (!FD->isAnonymousStructOrUnion()) { 5888 // Remember all fields written by the user. 5889 RecFields.push_back(FD); 5890 } 5891 5892 // If the field is already invalid for some reason, don't emit more 5893 // diagnostics about it. 5894 if (FD->isInvalidDecl()) { 5895 EnclosingDecl->setInvalidDecl(); 5896 continue; 5897 } 5898 5899 // C99 6.7.2.1p2: 5900 // A structure or union shall not contain a member with 5901 // incomplete or function type (hence, a structure shall not 5902 // contain an instance of itself, but may contain a pointer to 5903 // an instance of itself), except that the last member of a 5904 // structure with more than one named member may have incomplete 5905 // array type; such a structure (and any union containing, 5906 // possibly recursively, a member that is such a structure) 5907 // shall not be a member of a structure or an element of an 5908 // array. 5909 if (FDTy->isFunctionType()) { 5910 // Field declared as a function. 5911 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5912 << FD->getDeclName(); 5913 FD->setInvalidDecl(); 5914 EnclosingDecl->setInvalidDecl(); 5915 continue; 5916 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5917 Record && Record->isStruct()) { 5918 // Flexible array member. 5919 if (NumNamedMembers < 1) { 5920 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5921 << FD->getDeclName(); 5922 FD->setInvalidDecl(); 5923 EnclosingDecl->setInvalidDecl(); 5924 continue; 5925 } 5926 // Okay, we have a legal flexible array member at the end of the struct. 5927 if (Record) 5928 Record->setHasFlexibleArrayMember(true); 5929 } else if (!FDTy->isDependentType() && 5930 RequireCompleteType(FD->getLocation(), FD->getType(), 5931 diag::err_field_incomplete)) { 5932 // Incomplete type 5933 FD->setInvalidDecl(); 5934 EnclosingDecl->setInvalidDecl(); 5935 continue; 5936 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5937 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5938 // If this is a member of a union, then entire union becomes "flexible". 5939 if (Record && Record->isUnion()) { 5940 Record->setHasFlexibleArrayMember(true); 5941 } else { 5942 // If this is a struct/class and this is not the last element, reject 5943 // it. Note that GCC supports variable sized arrays in the middle of 5944 // structures. 5945 if (i != NumFields-1) 5946 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5947 << FD->getDeclName() << FD->getType(); 5948 else { 5949 // We support flexible arrays at the end of structs in 5950 // other structs as an extension. 5951 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5952 << FD->getDeclName(); 5953 if (Record) 5954 Record->setHasFlexibleArrayMember(true); 5955 } 5956 } 5957 } 5958 if (Record && FDTTy->getDecl()->hasObjectMember()) 5959 Record->setHasObjectMember(true); 5960 } else if (FDTy->isObjCInterfaceType()) { 5961 /// A field cannot be an Objective-c object 5962 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5963 FD->setInvalidDecl(); 5964 EnclosingDecl->setInvalidDecl(); 5965 continue; 5966 } else if (getLangOptions().ObjC1 && 5967 getLangOptions().getGCMode() != LangOptions::NonGC && 5968 Record && 5969 (FD->getType()->isObjCObjectPointerType() || 5970 FD->getType().isObjCGCStrong())) 5971 Record->setHasObjectMember(true); 5972 // Keep track of the number of named members. 5973 if (FD->getIdentifier()) 5974 ++NumNamedMembers; 5975 } 5976 5977 // Okay, we successfully defined 'Record'. 5978 if (Record) { 5979 Record->completeDefinition(Context); 5980 } else { 5981 ObjCIvarDecl **ClsFields = 5982 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5983 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5984 ID->setIVarList(ClsFields, RecFields.size(), Context); 5985 ID->setLocEnd(RBrac); 5986 // Add ivar's to class's DeclContext. 5987 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5988 ClsFields[i]->setLexicalDeclContext(ID); 5989 ID->addDecl(ClsFields[i]); 5990 } 5991 // Must enforce the rule that ivars in the base classes may not be 5992 // duplicates. 5993 if (ID->getSuperClass()) { 5994 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5995 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5996 ObjCIvarDecl* Ivar = (*IVI); 5997 5998 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5999 ObjCIvarDecl* prevIvar = 6000 ID->getSuperClass()->lookupInstanceVariable(II); 6001 if (prevIvar) { 6002 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 6003 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 6004 } 6005 } 6006 } 6007 } 6008 } else if (ObjCImplementationDecl *IMPDecl = 6009 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6010 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6011 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6012 // Ivar declared in @implementation never belongs to the implementation. 6013 // Only it is in implementation's lexical context. 6014 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6015 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6016 } 6017 } 6018 6019 if (Attr) 6020 ProcessDeclAttributeList(S, Record, Attr); 6021} 6022 6023EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6024 EnumConstantDecl *LastEnumConst, 6025 SourceLocation IdLoc, 6026 IdentifierInfo *Id, 6027 ExprArg val) { 6028 Expr *Val = (Expr *)val.get(); 6029 6030 llvm::APSInt EnumVal(32); 6031 QualType EltTy; 6032 if (Val) { 6033 if (Enum->isDependentType()) 6034 EltTy = Context.DependentTy; 6035 else { 6036 // Make sure to promote the operand type to int. 6037 UsualUnaryConversions(Val); 6038 if (Val != val.get()) { 6039 val.release(); 6040 val = Val; 6041 } 6042 6043 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6044 SourceLocation ExpLoc; 6045 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 6046 Val = 0; 6047 } else { 6048 EltTy = Val->getType(); 6049 } 6050 } 6051 } 6052 6053 if (!Val) { 6054 if (Enum->isDependentType()) 6055 EltTy = Context.DependentTy; 6056 else if (LastEnumConst) { 6057 // Assign the last value + 1. 6058 EnumVal = LastEnumConst->getInitVal(); 6059 ++EnumVal; 6060 6061 // Check for overflow on increment. 6062 if (EnumVal < LastEnumConst->getInitVal()) 6063 Diag(IdLoc, diag::warn_enum_value_overflow); 6064 6065 EltTy = LastEnumConst->getType(); 6066 } else { 6067 // First value, set to zero. 6068 EltTy = Context.IntTy; 6069 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 6070 EnumVal.setIsSigned(true); 6071 } 6072 } 6073 6074 assert(!EltTy.isNull() && "Enum constant with NULL type"); 6075 6076 val.release(); 6077 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6078 Val, EnumVal); 6079} 6080 6081 6082Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6083 DeclPtrTy lastEnumConst, 6084 SourceLocation IdLoc, 6085 IdentifierInfo *Id, 6086 SourceLocation EqualLoc, ExprTy *val) { 6087 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6088 EnumConstantDecl *LastEnumConst = 6089 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6090 Expr *Val = static_cast<Expr*>(val); 6091 6092 // The scope passed in may not be a decl scope. Zip up the scope tree until 6093 // we find one that is. 6094 S = getNonFieldDeclScope(S); 6095 6096 // Verify that there isn't already something declared with this name in this 6097 // scope. 6098 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 6099 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6100 // Maybe we will complain about the shadowed template parameter. 6101 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6102 // Just pretend that we didn't see the previous declaration. 6103 PrevDecl = 0; 6104 } 6105 6106 if (PrevDecl) { 6107 // When in C++, we may get a TagDecl with the same name; in this case the 6108 // enum constant will 'hide' the tag. 6109 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6110 "Received TagDecl when not in C++!"); 6111 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6112 if (isa<EnumConstantDecl>(PrevDecl)) 6113 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6114 else 6115 Diag(IdLoc, diag::err_redefinition) << Id; 6116 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6117 if (Val) Val->Destroy(Context); 6118 return DeclPtrTy(); 6119 } 6120 } 6121 6122 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6123 IdLoc, Id, Owned(Val)); 6124 6125 // Register this decl in the current scope stack. 6126 if (New) 6127 PushOnScopeChains(New, S); 6128 6129 return DeclPtrTy::make(New); 6130} 6131 6132void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6133 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6134 DeclPtrTy *Elements, unsigned NumElements, 6135 Scope *S, AttributeList *Attr) { 6136 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6137 QualType EnumType = Context.getTypeDeclType(Enum); 6138 6139 if (Attr) 6140 ProcessDeclAttributeList(S, Enum, Attr); 6141 6142 if (Enum->isDependentType()) { 6143 for (unsigned i = 0; i != NumElements; ++i) { 6144 EnumConstantDecl *ECD = 6145 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6146 if (!ECD) continue; 6147 6148 ECD->setType(EnumType); 6149 } 6150 6151 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 6152 return; 6153 } 6154 6155 // TODO: If the result value doesn't fit in an int, it must be a long or long 6156 // long value. ISO C does not support this, but GCC does as an extension, 6157 // emit a warning. 6158 unsigned IntWidth = Context.Target.getIntWidth(); 6159 unsigned CharWidth = Context.Target.getCharWidth(); 6160 unsigned ShortWidth = Context.Target.getShortWidth(); 6161 6162 // Verify that all the values are okay, compute the size of the values, and 6163 // reverse the list. 6164 unsigned NumNegativeBits = 0; 6165 unsigned NumPositiveBits = 0; 6166 6167 // Keep track of whether all elements have type int. 6168 bool AllElementsInt = true; 6169 6170 for (unsigned i = 0; i != NumElements; ++i) { 6171 EnumConstantDecl *ECD = 6172 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6173 if (!ECD) continue; // Already issued a diagnostic. 6174 6175 // If the enum value doesn't fit in an int, emit an extension warning. 6176 const llvm::APSInt &InitVal = ECD->getInitVal(); 6177 assert(InitVal.getBitWidth() >= IntWidth && 6178 "Should have promoted value to int"); 6179 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 6180 llvm::APSInt V(InitVal); 6181 V.trunc(IntWidth); 6182 V.extend(InitVal.getBitWidth()); 6183 if (V != InitVal) 6184 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 6185 << InitVal.toString(10); 6186 } 6187 6188 // Keep track of the size of positive and negative values. 6189 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6190 NumPositiveBits = std::max(NumPositiveBits, 6191 (unsigned)InitVal.getActiveBits()); 6192 else 6193 NumNegativeBits = std::max(NumNegativeBits, 6194 (unsigned)InitVal.getMinSignedBits()); 6195 6196 // Keep track of whether every enum element has type int (very commmon). 6197 if (AllElementsInt) 6198 AllElementsInt = ECD->getType() == Context.IntTy; 6199 } 6200 6201 // Figure out the type that should be used for this enum. 6202 // FIXME: Support -fshort-enums. 6203 QualType BestType; 6204 unsigned BestWidth; 6205 6206 // C++0x N3000 [conv.prom]p3: 6207 // An rvalue of an unscoped enumeration type whose underlying 6208 // type is not fixed can be converted to an rvalue of the first 6209 // of the following types that can represent all the values of 6210 // the enumeration: int, unsigned int, long int, unsigned long 6211 // int, long long int, or unsigned long long int. 6212 // C99 6.4.4.3p2: 6213 // An identifier declared as an enumeration constant has type int. 6214 // The C99 rule is modified by a gcc extension 6215 QualType BestPromotionType; 6216 6217 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6218 6219 if (NumNegativeBits) { 6220 // If there is a negative value, figure out the smallest integer type (of 6221 // int/long/longlong) that fits. 6222 // If it's packed, check also if it fits a char or a short. 6223 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6224 BestType = Context.SignedCharTy; 6225 BestWidth = CharWidth; 6226 } else if (Packed && NumNegativeBits <= ShortWidth && 6227 NumPositiveBits < ShortWidth) { 6228 BestType = Context.ShortTy; 6229 BestWidth = ShortWidth; 6230 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6231 BestType = Context.IntTy; 6232 BestWidth = IntWidth; 6233 } else { 6234 BestWidth = Context.Target.getLongWidth(); 6235 6236 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6237 BestType = Context.LongTy; 6238 } else { 6239 BestWidth = Context.Target.getLongLongWidth(); 6240 6241 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6242 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6243 BestType = Context.LongLongTy; 6244 } 6245 } 6246 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6247 } else { 6248 // If there is no negative value, figure out which of uint, ulong, ulonglong 6249 // fits. 6250 // If it's packed, check also if it fits a char or a short. 6251 if (Packed && NumPositiveBits <= CharWidth) { 6252 BestType = Context.UnsignedCharTy; 6253 BestPromotionType = Context.IntTy; 6254 BestWidth = CharWidth; 6255 } else if (Packed && NumPositiveBits <= ShortWidth) { 6256 BestType = Context.UnsignedShortTy; 6257 BestPromotionType = Context.IntTy; 6258 BestWidth = ShortWidth; 6259 } else if (NumPositiveBits <= IntWidth) { 6260 BestType = Context.UnsignedIntTy; 6261 BestWidth = IntWidth; 6262 BestPromotionType = (NumPositiveBits == BestWidth 6263 ? Context.UnsignedIntTy : Context.IntTy); 6264 } else if (NumPositiveBits <= 6265 (BestWidth = Context.Target.getLongWidth())) { 6266 BestType = Context.UnsignedLongTy; 6267 BestPromotionType = (NumPositiveBits == BestWidth 6268 ? Context.UnsignedLongTy : Context.LongTy); 6269 } else { 6270 BestWidth = Context.Target.getLongLongWidth(); 6271 assert(NumPositiveBits <= BestWidth && 6272 "How could an initializer get larger than ULL?"); 6273 BestType = Context.UnsignedLongLongTy; 6274 BestPromotionType = (NumPositiveBits == BestWidth 6275 ? Context.UnsignedLongLongTy : Context.LongLongTy); 6276 } 6277 } 6278 6279 // If we're in C and the promotion type is larger than an int, just 6280 // use the underlying type, which is generally the unsigned integer 6281 // type of the same rank as the promotion type. This is how the gcc 6282 // extension works. 6283 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 6284 BestPromotionType = BestType; 6285 6286 // Loop over all of the enumerator constants, changing their types to match 6287 // the type of the enum if needed. 6288 for (unsigned i = 0; i != NumElements; ++i) { 6289 EnumConstantDecl *ECD = 6290 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6291 if (!ECD) continue; // Already issued a diagnostic. 6292 6293 // Standard C says the enumerators have int type, but we allow, as an 6294 // extension, the enumerators to be larger than int size. If each 6295 // enumerator value fits in an int, type it as an int, otherwise type it the 6296 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6297 // that X has type 'int', not 'unsigned'. 6298 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 6299 continue; 6300 6301 // Determine whether the value fits into an int. 6302 llvm::APSInt InitVal = ECD->getInitVal(); 6303 bool FitsInInt; 6304 if (InitVal.isUnsigned() || !InitVal.isNegative()) 6305 FitsInInt = InitVal.getActiveBits() < IntWidth; 6306 else 6307 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 6308 6309 // If it fits into an integer type, force it. Otherwise force it to match 6310 // the enum decl type. 6311 QualType NewTy; 6312 unsigned NewWidth; 6313 bool NewSign; 6314 if (FitsInInt && !getLangOptions().CPlusPlus) { 6315 NewTy = Context.IntTy; 6316 NewWidth = IntWidth; 6317 NewSign = true; 6318 } else if (ECD->getType() == BestType) { 6319 // Already the right type! 6320 if (getLangOptions().CPlusPlus) 6321 // C++ [dcl.enum]p4: Following the closing brace of an 6322 // enum-specifier, each enumerator has the type of its 6323 // enumeration. 6324 ECD->setType(EnumType); 6325 continue; 6326 } else { 6327 NewTy = BestType; 6328 NewWidth = BestWidth; 6329 NewSign = BestType->isSignedIntegerType(); 6330 } 6331 6332 // Adjust the APSInt value. 6333 InitVal.extOrTrunc(NewWidth); 6334 InitVal.setIsSigned(NewSign); 6335 ECD->setInitVal(InitVal); 6336 6337 // Adjust the Expr initializer and type. 6338 if (ECD->getInitExpr()) 6339 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6340 CastExpr::CK_IntegralCast, 6341 ECD->getInitExpr(), 6342 /*isLvalue=*/false)); 6343 if (getLangOptions().CPlusPlus) 6344 // C++ [dcl.enum]p4: Following the closing brace of an 6345 // enum-specifier, each enumerator has the type of its 6346 // enumeration. 6347 ECD->setType(EnumType); 6348 else 6349 ECD->setType(NewTy); 6350 } 6351 6352 Enum->completeDefinition(Context, BestType, BestPromotionType); 6353} 6354 6355Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6356 ExprArg expr) { 6357 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6358 6359 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6360 Loc, AsmString); 6361 CurContext->addDecl(New); 6362 return DeclPtrTy::make(New); 6363} 6364 6365void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6366 SourceLocation PragmaLoc, 6367 SourceLocation NameLoc) { 6368 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6369 6370 if (PrevDecl) { 6371 PrevDecl->addAttr(::new (Context) WeakAttr()); 6372 } else { 6373 (void)WeakUndeclaredIdentifiers.insert( 6374 std::pair<IdentifierInfo*,WeakInfo> 6375 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6376 } 6377} 6378 6379void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6380 IdentifierInfo* AliasName, 6381 SourceLocation PragmaLoc, 6382 SourceLocation NameLoc, 6383 SourceLocation AliasNameLoc) { 6384 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6385 WeakInfo W = WeakInfo(Name, NameLoc); 6386 6387 if (PrevDecl) { 6388 if (!PrevDecl->hasAttr<AliasAttr>()) 6389 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6390 DeclApplyPragmaWeak(TUScope, ND, W); 6391 } else { 6392 (void)WeakUndeclaredIdentifiers.insert( 6393 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6394 } 6395} 6396