SemaDecl.cpp revision 7d3f576dc9ea6e866757abcd1736eb7e7433c325
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 1331/// CheckUnreachable - Check for unreachable code. 1332void Sema::CheckUnreachable(AnalysisContext &AC) { 1333 // We avoid checking when there are errors, as the CFG won't faithfully match 1334 // the user's code. 1335 if (getDiagnostics().hasErrorOccurred()) 1336 return; 1337 if (Diags.getDiagnosticLevel(diag::warn_unreachable) == Diagnostic::Ignored) 1338 return; 1339 1340 CFG *cfg = AC.getCFG(); 1341 if (cfg == 0) 1342 return; 1343 1344 llvm::BitVector live(cfg->getNumBlockIDs()); 1345 // Mark all live things first. 1346 MarkLive(&cfg->getEntry(), live); 1347 1348 for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) { 1349 CFGBlock &b = **I; 1350 if (!live[b.getBlockID()]) { 1351 if (!b.empty()) 1352 Diag(b[0].getStmt()->getLocStart(), diag::warn_unreachable); 1353 // Avoid excessive errors by marking everything reachable from here 1354 MarkLive(&b, live); 1355 } 1356 } 1357} 1358 1359/// CheckFallThrough - Check that we don't fall off the end of a 1360/// Statement that should return a value. 1361/// 1362/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1363/// MaybeFallThrough iff we might or might not fall off the end, 1364/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1365/// return. We assume NeverFallThrough iff we never fall off the end of the 1366/// statement but we may return. We assume that functions not marked noreturn 1367/// will return. 1368Sema::ControlFlowKind Sema::CheckFallThrough(AnalysisContext &AC) { 1369 CFG *cfg = AC.getCFG(); 1370 if (cfg == 0) 1371 // FIXME: This should be NeverFallThrough 1372 return NeverFallThroughOrReturn; 1373 1374 // The CFG leaves in dead things, and we don't want to dead code paths to 1375 // confuse us, so we mark all live things first. 1376 std::queue<CFGBlock*> workq; 1377 llvm::BitVector live(cfg->getNumBlockIDs()); 1378 MarkLive(&cfg->getEntry(), live); 1379 1380 // Now we know what is live, we check the live precessors of the exit block 1381 // and look for fall through paths, being careful to ignore normal returns, 1382 // and exceptional paths. 1383 bool HasLiveReturn = false; 1384 bool HasFakeEdge = false; 1385 bool HasPlainEdge = false; 1386 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1387 E = cfg->getExit().pred_end(); 1388 I != E; 1389 ++I) { 1390 CFGBlock& B = **I; 1391 if (!live[B.getBlockID()]) 1392 continue; 1393 if (B.size() == 0) { 1394 // A labeled empty statement, or the entry block... 1395 HasPlainEdge = true; 1396 continue; 1397 } 1398 Stmt *S = B[B.size()-1]; 1399 if (isa<ReturnStmt>(S)) { 1400 HasLiveReturn = true; 1401 continue; 1402 } 1403 if (isa<ObjCAtThrowStmt>(S)) { 1404 HasFakeEdge = true; 1405 continue; 1406 } 1407 if (isa<CXXThrowExpr>(S)) { 1408 HasFakeEdge = true; 1409 continue; 1410 } 1411 if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) { 1412 if (AS->isMSAsm()) { 1413 HasFakeEdge = true; 1414 HasLiveReturn = true; 1415 continue; 1416 } 1417 } 1418 1419 bool NoReturnEdge = false; 1420 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1421 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1422 if (CEE->getType().getNoReturnAttr()) { 1423 NoReturnEdge = true; 1424 HasFakeEdge = true; 1425 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1426 ValueDecl *VD = DRE->getDecl(); 1427 if (VD->hasAttr<NoReturnAttr>()) { 1428 NoReturnEdge = true; 1429 HasFakeEdge = true; 1430 } 1431 } 1432 } 1433 // FIXME: Add noreturn message sends. 1434 if (NoReturnEdge == false) 1435 HasPlainEdge = true; 1436 } 1437 if (!HasPlainEdge) { 1438 if (HasLiveReturn) 1439 return NeverFallThrough; 1440 return NeverFallThroughOrReturn; 1441 } 1442 if (HasFakeEdge || HasLiveReturn) 1443 return MaybeFallThrough; 1444 // This says AlwaysFallThrough for calls to functions that are not marked 1445 // noreturn, that don't return. If people would like this warning to be more 1446 // accurate, such functions should be marked as noreturn. 1447 return AlwaysFallThrough; 1448} 1449 1450/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1451/// function that should return a value. Check that we don't fall off the end 1452/// of a noreturn function. We assume that functions and blocks not marked 1453/// noreturn will return. 1454void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body, 1455 AnalysisContext &AC) { 1456 // FIXME: Would be nice if we had a better way to control cascading errors, 1457 // but for now, avoid them. The problem is that when Parse sees: 1458 // int foo() { return a; } 1459 // The return is eaten and the Sema code sees just: 1460 // int foo() { } 1461 // which this code would then warn about. 1462 if (getDiagnostics().hasErrorOccurred()) 1463 return; 1464 1465 bool ReturnsVoid = false; 1466 bool HasNoReturn = false; 1467 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1468 // If the result type of the function is a dependent type, we don't know 1469 // whether it will be void or not, so don't 1470 if (FD->getResultType()->isDependentType()) 1471 return; 1472 if (FD->getResultType()->isVoidType()) 1473 ReturnsVoid = true; 1474 if (FD->hasAttr<NoReturnAttr>()) 1475 HasNoReturn = true; 1476 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1477 if (MD->getResultType()->isVoidType()) 1478 ReturnsVoid = true; 1479 if (MD->hasAttr<NoReturnAttr>()) 1480 HasNoReturn = true; 1481 } 1482 1483 // Short circuit for compilation speed. 1484 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1485 == Diagnostic::Ignored || ReturnsVoid) 1486 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1487 == Diagnostic::Ignored || !HasNoReturn) 1488 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1489 == Diagnostic::Ignored || !ReturnsVoid)) 1490 return; 1491 // FIXME: Function try block 1492 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1493 switch (CheckFallThrough(AC)) { 1494 case MaybeFallThrough: 1495 if (HasNoReturn) 1496 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1497 else if (!ReturnsVoid) 1498 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1499 break; 1500 case AlwaysFallThrough: 1501 if (HasNoReturn) 1502 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1503 else if (!ReturnsVoid) 1504 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1505 break; 1506 case NeverFallThroughOrReturn: 1507 if (ReturnsVoid && !HasNoReturn) 1508 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1509 break; 1510 case NeverFallThrough: 1511 break; 1512 } 1513 } 1514} 1515 1516/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1517/// that should return a value. Check that we don't fall off the end of a 1518/// noreturn block. We assume that functions and blocks not marked noreturn 1519/// will return. 1520void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body, 1521 AnalysisContext &AC) { 1522 // FIXME: Would be nice if we had a better way to control cascading errors, 1523 // but for now, avoid them. The problem is that when Parse sees: 1524 // int foo() { return a; } 1525 // The return is eaten and the Sema code sees just: 1526 // int foo() { } 1527 // which this code would then warn about. 1528 if (getDiagnostics().hasErrorOccurred()) 1529 return; 1530 bool ReturnsVoid = false; 1531 bool HasNoReturn = false; 1532 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1533 if (FT->getResultType()->isVoidType()) 1534 ReturnsVoid = true; 1535 if (FT->getNoReturnAttr()) 1536 HasNoReturn = true; 1537 } 1538 1539 // Short circuit for compilation speed. 1540 if (ReturnsVoid 1541 && !HasNoReturn 1542 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1543 == Diagnostic::Ignored || !ReturnsVoid)) 1544 return; 1545 // FIXME: Funtion try block 1546 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1547 switch (CheckFallThrough(AC)) { 1548 case MaybeFallThrough: 1549 if (HasNoReturn) 1550 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1551 else if (!ReturnsVoid) 1552 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1553 break; 1554 case AlwaysFallThrough: 1555 if (HasNoReturn) 1556 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1557 else if (!ReturnsVoid) 1558 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1559 break; 1560 case NeverFallThroughOrReturn: 1561 if (ReturnsVoid) 1562 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1563 break; 1564 case NeverFallThrough: 1565 break; 1566 } 1567 } 1568} 1569 1570/// CheckParmsForFunctionDef - Check that the parameters of the given 1571/// function are appropriate for the definition of a function. This 1572/// takes care of any checks that cannot be performed on the 1573/// declaration itself, e.g., that the types of each of the function 1574/// parameters are complete. 1575bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1576 bool HasInvalidParm = false; 1577 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1578 ParmVarDecl *Param = FD->getParamDecl(p); 1579 1580 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1581 // function declarator that is part of a function definition of 1582 // that function shall not have incomplete type. 1583 // 1584 // This is also C++ [dcl.fct]p6. 1585 if (!Param->isInvalidDecl() && 1586 RequireCompleteType(Param->getLocation(), Param->getType(), 1587 diag::err_typecheck_decl_incomplete_type)) { 1588 Param->setInvalidDecl(); 1589 HasInvalidParm = true; 1590 } 1591 1592 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1593 // declaration of each parameter shall include an identifier. 1594 if (Param->getIdentifier() == 0 && 1595 !Param->isImplicit() && 1596 !getLangOptions().CPlusPlus) 1597 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1598 } 1599 1600 return HasInvalidParm; 1601} 1602 1603/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1604/// no declarator (e.g. "struct foo;") is parsed. 1605Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1606 // FIXME: Error on auto/register at file scope 1607 // FIXME: Error on inline/virtual/explicit 1608 // FIXME: Warn on useless __thread 1609 // FIXME: Warn on useless const/volatile 1610 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1611 // FIXME: Warn on useless attributes 1612 Decl *TagD = 0; 1613 TagDecl *Tag = 0; 1614 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1615 DS.getTypeSpecType() == DeclSpec::TST_struct || 1616 DS.getTypeSpecType() == DeclSpec::TST_union || 1617 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1618 TagD = static_cast<Decl *>(DS.getTypeRep()); 1619 1620 if (!TagD) // We probably had an error 1621 return DeclPtrTy(); 1622 1623 // Note that the above type specs guarantee that the 1624 // type rep is a Decl, whereas in many of the others 1625 // it's a Type. 1626 Tag = dyn_cast<TagDecl>(TagD); 1627 } 1628 1629 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1630 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1631 // or incomplete types shall not be restrict-qualified." 1632 if (TypeQuals & DeclSpec::TQ_restrict) 1633 Diag(DS.getRestrictSpecLoc(), 1634 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1635 << DS.getSourceRange(); 1636 } 1637 1638 if (DS.isFriendSpecified()) { 1639 // If we're dealing with a class template decl, assume that the 1640 // template routines are handling it. 1641 if (TagD && isa<ClassTemplateDecl>(TagD)) 1642 return DeclPtrTy(); 1643 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1644 } 1645 1646 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1647 // If there are attributes in the DeclSpec, apply them to the record. 1648 if (const AttributeList *AL = DS.getAttributes()) 1649 ProcessDeclAttributeList(S, Record, AL); 1650 1651 if (!Record->getDeclName() && Record->isDefinition() && 1652 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1653 if (getLangOptions().CPlusPlus || 1654 Record->getDeclContext()->isRecord()) 1655 return BuildAnonymousStructOrUnion(S, DS, Record); 1656 1657 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1658 << DS.getSourceRange(); 1659 } 1660 1661 // Microsoft allows unnamed struct/union fields. Don't complain 1662 // about them. 1663 // FIXME: Should we support Microsoft's extensions in this area? 1664 if (Record->getDeclName() && getLangOptions().Microsoft) 1665 return DeclPtrTy::make(Tag); 1666 } 1667 1668 if (!DS.isMissingDeclaratorOk() && 1669 DS.getTypeSpecType() != DeclSpec::TST_error) { 1670 // Warn about typedefs of enums without names, since this is an 1671 // extension in both Microsoft an GNU. 1672 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1673 Tag && isa<EnumDecl>(Tag)) { 1674 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1675 << DS.getSourceRange(); 1676 return DeclPtrTy::make(Tag); 1677 } 1678 1679 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1680 << DS.getSourceRange(); 1681 return DeclPtrTy(); 1682 } 1683 1684 return DeclPtrTy::make(Tag); 1685} 1686 1687/// We are trying to inject an anonymous member into the given scope; 1688/// check if there's an existing declaration that can't be overloaded. 1689/// 1690/// \return true if this is a forbidden redeclaration 1691static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1692 Scope *S, 1693 DeclarationName Name, 1694 SourceLocation NameLoc, 1695 unsigned diagnostic) { 1696 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1697 Sema::ForRedeclaration); 1698 if (!SemaRef.LookupName(R, S)) return false; 1699 1700 if (R.getAsSingle<TagDecl>()) 1701 return false; 1702 1703 // Pick a representative declaration. 1704 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1705 1706 SemaRef.Diag(NameLoc, diagnostic) << Name; 1707 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1708 1709 return true; 1710} 1711 1712/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1713/// anonymous struct or union AnonRecord into the owning context Owner 1714/// and scope S. This routine will be invoked just after we realize 1715/// that an unnamed union or struct is actually an anonymous union or 1716/// struct, e.g., 1717/// 1718/// @code 1719/// union { 1720/// int i; 1721/// float f; 1722/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1723/// // f into the surrounding scope.x 1724/// @endcode 1725/// 1726/// This routine is recursive, injecting the names of nested anonymous 1727/// structs/unions into the owning context and scope as well. 1728bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1729 RecordDecl *AnonRecord) { 1730 unsigned diagKind 1731 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1732 : diag::err_anonymous_struct_member_redecl; 1733 1734 bool Invalid = false; 1735 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1736 FEnd = AnonRecord->field_end(); 1737 F != FEnd; ++F) { 1738 if ((*F)->getDeclName()) { 1739 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1740 (*F)->getLocation(), diagKind)) { 1741 // C++ [class.union]p2: 1742 // The names of the members of an anonymous union shall be 1743 // distinct from the names of any other entity in the 1744 // scope in which the anonymous union is declared. 1745 Invalid = true; 1746 } else { 1747 // C++ [class.union]p2: 1748 // For the purpose of name lookup, after the anonymous union 1749 // definition, the members of the anonymous union are 1750 // considered to have been defined in the scope in which the 1751 // anonymous union is declared. 1752 Owner->makeDeclVisibleInContext(*F); 1753 S->AddDecl(DeclPtrTy::make(*F)); 1754 IdResolver.AddDecl(*F); 1755 } 1756 } else if (const RecordType *InnerRecordType 1757 = (*F)->getType()->getAs<RecordType>()) { 1758 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1759 if (InnerRecord->isAnonymousStructOrUnion()) 1760 Invalid = Invalid || 1761 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1762 } 1763 } 1764 1765 return Invalid; 1766} 1767 1768/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1769/// anonymous structure or union. Anonymous unions are a C++ feature 1770/// (C++ [class.union]) and a GNU C extension; anonymous structures 1771/// are a GNU C and GNU C++ extension. 1772Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1773 RecordDecl *Record) { 1774 DeclContext *Owner = Record->getDeclContext(); 1775 1776 // Diagnose whether this anonymous struct/union is an extension. 1777 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1778 Diag(Record->getLocation(), diag::ext_anonymous_union); 1779 else if (!Record->isUnion()) 1780 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1781 1782 // C and C++ require different kinds of checks for anonymous 1783 // structs/unions. 1784 bool Invalid = false; 1785 if (getLangOptions().CPlusPlus) { 1786 const char* PrevSpec = 0; 1787 unsigned DiagID; 1788 // C++ [class.union]p3: 1789 // Anonymous unions declared in a named namespace or in the 1790 // global namespace shall be declared static. 1791 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1792 (isa<TranslationUnitDecl>(Owner) || 1793 (isa<NamespaceDecl>(Owner) && 1794 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1795 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1796 Invalid = true; 1797 1798 // Recover by adding 'static'. 1799 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1800 PrevSpec, DiagID); 1801 } 1802 // C++ [class.union]p3: 1803 // A storage class is not allowed in a declaration of an 1804 // anonymous union in a class scope. 1805 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1806 isa<RecordDecl>(Owner)) { 1807 Diag(DS.getStorageClassSpecLoc(), 1808 diag::err_anonymous_union_with_storage_spec); 1809 Invalid = true; 1810 1811 // Recover by removing the storage specifier. 1812 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1813 PrevSpec, DiagID); 1814 } 1815 1816 // C++ [class.union]p2: 1817 // The member-specification of an anonymous union shall only 1818 // define non-static data members. [Note: nested types and 1819 // functions cannot be declared within an anonymous union. ] 1820 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1821 MemEnd = Record->decls_end(); 1822 Mem != MemEnd; ++Mem) { 1823 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1824 // C++ [class.union]p3: 1825 // An anonymous union shall not have private or protected 1826 // members (clause 11). 1827 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1828 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1829 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1830 Invalid = true; 1831 } 1832 } else if ((*Mem)->isImplicit()) { 1833 // Any implicit members are fine. 1834 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1835 // This is a type that showed up in an 1836 // elaborated-type-specifier inside the anonymous struct or 1837 // union, but which actually declares a type outside of the 1838 // anonymous struct or union. It's okay. 1839 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1840 if (!MemRecord->isAnonymousStructOrUnion() && 1841 MemRecord->getDeclName()) { 1842 // This is a nested type declaration. 1843 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1844 << (int)Record->isUnion(); 1845 Invalid = true; 1846 } 1847 } else { 1848 // We have something that isn't a non-static data 1849 // member. Complain about it. 1850 unsigned DK = diag::err_anonymous_record_bad_member; 1851 if (isa<TypeDecl>(*Mem)) 1852 DK = diag::err_anonymous_record_with_type; 1853 else if (isa<FunctionDecl>(*Mem)) 1854 DK = diag::err_anonymous_record_with_function; 1855 else if (isa<VarDecl>(*Mem)) 1856 DK = diag::err_anonymous_record_with_static; 1857 Diag((*Mem)->getLocation(), DK) 1858 << (int)Record->isUnion(); 1859 Invalid = true; 1860 } 1861 } 1862 } 1863 1864 if (!Record->isUnion() && !Owner->isRecord()) { 1865 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1866 << (int)getLangOptions().CPlusPlus; 1867 Invalid = true; 1868 } 1869 1870 // Mock up a declarator. 1871 Declarator Dc(DS, Declarator::TypeNameContext); 1872 TypeSourceInfo *TInfo = 0; 1873 GetTypeForDeclarator(Dc, S, &TInfo); 1874 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1875 1876 // Create a declaration for this anonymous struct/union. 1877 NamedDecl *Anon = 0; 1878 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1879 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1880 /*IdentifierInfo=*/0, 1881 Context.getTypeDeclType(Record), 1882 TInfo, 1883 /*BitWidth=*/0, /*Mutable=*/false); 1884 Anon->setAccess(AS_public); 1885 if (getLangOptions().CPlusPlus) 1886 FieldCollector->Add(cast<FieldDecl>(Anon)); 1887 } else { 1888 VarDecl::StorageClass SC; 1889 switch (DS.getStorageClassSpec()) { 1890 default: assert(0 && "Unknown storage class!"); 1891 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1892 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1893 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1894 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1895 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1896 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1897 case DeclSpec::SCS_mutable: 1898 // mutable can only appear on non-static class members, so it's always 1899 // an error here 1900 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1901 Invalid = true; 1902 SC = VarDecl::None; 1903 break; 1904 } 1905 1906 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1907 /*IdentifierInfo=*/0, 1908 Context.getTypeDeclType(Record), 1909 TInfo, 1910 SC); 1911 } 1912 Anon->setImplicit(); 1913 1914 // Add the anonymous struct/union object to the current 1915 // context. We'll be referencing this object when we refer to one of 1916 // its members. 1917 Owner->addDecl(Anon); 1918 1919 // Inject the members of the anonymous struct/union into the owning 1920 // context and into the identifier resolver chain for name lookup 1921 // purposes. 1922 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1923 Invalid = true; 1924 1925 // Mark this as an anonymous struct/union type. Note that we do not 1926 // do this until after we have already checked and injected the 1927 // members of this anonymous struct/union type, because otherwise 1928 // the members could be injected twice: once by DeclContext when it 1929 // builds its lookup table, and once by 1930 // InjectAnonymousStructOrUnionMembers. 1931 Record->setAnonymousStructOrUnion(true); 1932 1933 if (Invalid) 1934 Anon->setInvalidDecl(); 1935 1936 return DeclPtrTy::make(Anon); 1937} 1938 1939 1940/// GetNameForDeclarator - Determine the full declaration name for the 1941/// given Declarator. 1942DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1943 return GetNameFromUnqualifiedId(D.getName()); 1944} 1945 1946/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1947DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1948 switch (Name.getKind()) { 1949 case UnqualifiedId::IK_Identifier: 1950 return DeclarationName(Name.Identifier); 1951 1952 case UnqualifiedId::IK_OperatorFunctionId: 1953 return Context.DeclarationNames.getCXXOperatorName( 1954 Name.OperatorFunctionId.Operator); 1955 1956 case UnqualifiedId::IK_LiteralOperatorId: 1957 return Context.DeclarationNames.getCXXLiteralOperatorName( 1958 Name.Identifier); 1959 1960 case UnqualifiedId::IK_ConversionFunctionId: { 1961 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1962 if (Ty.isNull()) 1963 return DeclarationName(); 1964 1965 return Context.DeclarationNames.getCXXConversionFunctionName( 1966 Context.getCanonicalType(Ty)); 1967 } 1968 1969 case UnqualifiedId::IK_ConstructorName: { 1970 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1971 if (Ty.isNull()) 1972 return DeclarationName(); 1973 1974 return Context.DeclarationNames.getCXXConstructorName( 1975 Context.getCanonicalType(Ty)); 1976 } 1977 1978 case UnqualifiedId::IK_ConstructorTemplateId: { 1979 // In well-formed code, we can only have a constructor 1980 // template-id that refers to the current context, so go there 1981 // to find the actual type being constructed. 1982 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1983 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1984 return DeclarationName(); 1985 1986 // Determine the type of the class being constructed. 1987 QualType CurClassType; 1988 if (ClassTemplateDecl *ClassTemplate 1989 = CurClass->getDescribedClassTemplate()) 1990 CurClassType = ClassTemplate->getInjectedClassNameType(Context); 1991 else 1992 CurClassType = Context.getTypeDeclType(CurClass); 1993 1994 // FIXME: Check two things: that the template-id names the same type as 1995 // CurClassType, and that the template-id does not occur when the name 1996 // was qualified. 1997 1998 return Context.DeclarationNames.getCXXConstructorName( 1999 Context.getCanonicalType(CurClassType)); 2000 } 2001 2002 case UnqualifiedId::IK_DestructorName: { 2003 QualType Ty = GetTypeFromParser(Name.DestructorName); 2004 if (Ty.isNull()) 2005 return DeclarationName(); 2006 2007 return Context.DeclarationNames.getCXXDestructorName( 2008 Context.getCanonicalType(Ty)); 2009 } 2010 2011 case UnqualifiedId::IK_TemplateId: { 2012 TemplateName TName 2013 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2014 return Context.getNameForTemplate(TName); 2015 } 2016 } 2017 2018 assert(false && "Unknown name kind"); 2019 return DeclarationName(); 2020} 2021 2022/// isNearlyMatchingFunction - Determine whether the C++ functions 2023/// Declaration and Definition are "nearly" matching. This heuristic 2024/// is used to improve diagnostics in the case where an out-of-line 2025/// function definition doesn't match any declaration within 2026/// the class or namespace. 2027static bool isNearlyMatchingFunction(ASTContext &Context, 2028 FunctionDecl *Declaration, 2029 FunctionDecl *Definition) { 2030 if (Declaration->param_size() != Definition->param_size()) 2031 return false; 2032 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2033 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2034 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2035 2036 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2037 DefParamTy.getNonReferenceType())) 2038 return false; 2039 } 2040 2041 return true; 2042} 2043 2044Sema::DeclPtrTy 2045Sema::HandleDeclarator(Scope *S, Declarator &D, 2046 MultiTemplateParamsArg TemplateParamLists, 2047 bool IsFunctionDefinition) { 2048 DeclarationName Name = GetNameForDeclarator(D); 2049 2050 // All of these full declarators require an identifier. If it doesn't have 2051 // one, the ParsedFreeStandingDeclSpec action should be used. 2052 if (!Name) { 2053 if (!D.isInvalidType()) // Reject this if we think it is valid. 2054 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2055 diag::err_declarator_need_ident) 2056 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2057 return DeclPtrTy(); 2058 } 2059 2060 // The scope passed in may not be a decl scope. Zip up the scope tree until 2061 // we find one that is. 2062 while ((S->getFlags() & Scope::DeclScope) == 0 || 2063 (S->getFlags() & Scope::TemplateParamScope) != 0) 2064 S = S->getParent(); 2065 2066 // If this is an out-of-line definition of a member of a class template 2067 // or class template partial specialization, we may need to rebuild the 2068 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 2069 // for more information. 2070 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 2071 // handle expressions properly. 2072 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 2073 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 2074 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 2075 (DS.getTypeSpecType() == DeclSpec::TST_typename || 2076 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 2077 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 2078 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 2079 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 2080 // FIXME: Preserve type source info. 2081 QualType T = GetTypeFromParser(DS.getTypeRep()); 2082 2083 DeclContext *SavedContext = CurContext; 2084 CurContext = DC; 2085 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 2086 CurContext = SavedContext; 2087 2088 if (T.isNull()) 2089 return DeclPtrTy(); 2090 DS.UpdateTypeRep(T.getAsOpaquePtr()); 2091 } 2092 } 2093 2094 DeclContext *DC; 2095 NamedDecl *New; 2096 2097 TypeSourceInfo *TInfo = 0; 2098 QualType R = GetTypeForDeclarator(D, S, &TInfo); 2099 2100 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2101 ForRedeclaration); 2102 2103 // See if this is a redefinition of a variable in the same scope. 2104 if (D.getCXXScopeSpec().isInvalid()) { 2105 DC = CurContext; 2106 D.setInvalidType(); 2107 } else if (!D.getCXXScopeSpec().isSet()) { 2108 bool IsLinkageLookup = false; 2109 2110 // If the declaration we're planning to build will be a function 2111 // or object with linkage, then look for another declaration with 2112 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2113 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2114 /* Do nothing*/; 2115 else if (R->isFunctionType()) { 2116 if (CurContext->isFunctionOrMethod() || 2117 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2118 IsLinkageLookup = true; 2119 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2120 IsLinkageLookup = true; 2121 else if (CurContext->getLookupContext()->isTranslationUnit() && 2122 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2123 IsLinkageLookup = true; 2124 2125 if (IsLinkageLookup) 2126 Previous.clear(LookupRedeclarationWithLinkage); 2127 2128 DC = CurContext; 2129 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2130 } else { // Something like "int foo::x;" 2131 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2132 2133 if (!DC) { 2134 // If we could not compute the declaration context, it's because the 2135 // declaration context is dependent but does not refer to a class, 2136 // class template, or class template partial specialization. Complain 2137 // and return early, to avoid the coming semantic disaster. 2138 Diag(D.getIdentifierLoc(), 2139 diag::err_template_qualified_declarator_no_match) 2140 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2141 << D.getCXXScopeSpec().getRange(); 2142 return DeclPtrTy(); 2143 } 2144 2145 if (!DC->isDependentContext() && 2146 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2147 return DeclPtrTy(); 2148 2149 LookupQualifiedName(Previous, DC); 2150 2151 // Don't consider using declarations as previous declarations for 2152 // out-of-line members. 2153 RemoveUsingDecls(Previous); 2154 2155 // C++ 7.3.1.2p2: 2156 // Members (including explicit specializations of templates) of a named 2157 // namespace can also be defined outside that namespace by explicit 2158 // qualification of the name being defined, provided that the entity being 2159 // defined was already declared in the namespace and the definition appears 2160 // after the point of declaration in a namespace that encloses the 2161 // declarations namespace. 2162 // 2163 // Note that we only check the context at this point. We don't yet 2164 // have enough information to make sure that PrevDecl is actually 2165 // the declaration we want to match. For example, given: 2166 // 2167 // class X { 2168 // void f(); 2169 // void f(float); 2170 // }; 2171 // 2172 // void X::f(int) { } // ill-formed 2173 // 2174 // In this case, PrevDecl will point to the overload set 2175 // containing the two f's declared in X, but neither of them 2176 // matches. 2177 2178 // First check whether we named the global scope. 2179 if (isa<TranslationUnitDecl>(DC)) { 2180 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2181 << Name << D.getCXXScopeSpec().getRange(); 2182 } else { 2183 DeclContext *Cur = CurContext; 2184 while (isa<LinkageSpecDecl>(Cur)) 2185 Cur = Cur->getParent(); 2186 if (!Cur->Encloses(DC)) { 2187 // The qualifying scope doesn't enclose the original declaration. 2188 // Emit diagnostic based on current scope. 2189 SourceLocation L = D.getIdentifierLoc(); 2190 SourceRange R = D.getCXXScopeSpec().getRange(); 2191 if (isa<FunctionDecl>(Cur)) 2192 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2193 else 2194 Diag(L, diag::err_invalid_declarator_scope) 2195 << Name << cast<NamedDecl>(DC) << R; 2196 D.setInvalidType(); 2197 } 2198 } 2199 } 2200 2201 if (Previous.isSingleResult() && 2202 Previous.getFoundDecl()->isTemplateParameter()) { 2203 // Maybe we will complain about the shadowed template parameter. 2204 if (!D.isInvalidType()) 2205 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2206 Previous.getFoundDecl())) 2207 D.setInvalidType(); 2208 2209 // Just pretend that we didn't see the previous declaration. 2210 Previous.clear(); 2211 } 2212 2213 // In C++, the previous declaration we find might be a tag type 2214 // (class or enum). In this case, the new declaration will hide the 2215 // tag type. Note that this does does not apply if we're declaring a 2216 // typedef (C++ [dcl.typedef]p4). 2217 if (Previous.isSingleTagDecl() && 2218 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2219 Previous.clear(); 2220 2221 bool Redeclaration = false; 2222 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2223 if (TemplateParamLists.size()) { 2224 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2225 return DeclPtrTy(); 2226 } 2227 2228 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2229 } else if (R->isFunctionType()) { 2230 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2231 move(TemplateParamLists), 2232 IsFunctionDefinition, Redeclaration); 2233 } else { 2234 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2235 move(TemplateParamLists), 2236 Redeclaration); 2237 } 2238 2239 if (New == 0) 2240 return DeclPtrTy(); 2241 2242 // If this has an identifier and is not an invalid redeclaration or 2243 // function template specialization, add it to the scope stack. 2244 if (Name && !(Redeclaration && New->isInvalidDecl())) 2245 PushOnScopeChains(New, S); 2246 2247 return DeclPtrTy::make(New); 2248} 2249 2250/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2251/// types into constant array types in certain situations which would otherwise 2252/// be errors (for GCC compatibility). 2253static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2254 ASTContext &Context, 2255 bool &SizeIsNegative) { 2256 // This method tries to turn a variable array into a constant 2257 // array even when the size isn't an ICE. This is necessary 2258 // for compatibility with code that depends on gcc's buggy 2259 // constant expression folding, like struct {char x[(int)(char*)2];} 2260 SizeIsNegative = false; 2261 2262 QualifierCollector Qs; 2263 const Type *Ty = Qs.strip(T); 2264 2265 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2266 QualType Pointee = PTy->getPointeeType(); 2267 QualType FixedType = 2268 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2269 if (FixedType.isNull()) return FixedType; 2270 FixedType = Context.getPointerType(FixedType); 2271 return Qs.apply(FixedType); 2272 } 2273 2274 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2275 if (!VLATy) 2276 return QualType(); 2277 // FIXME: We should probably handle this case 2278 if (VLATy->getElementType()->isVariablyModifiedType()) 2279 return QualType(); 2280 2281 Expr::EvalResult EvalResult; 2282 if (!VLATy->getSizeExpr() || 2283 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2284 !EvalResult.Val.isInt()) 2285 return QualType(); 2286 2287 llvm::APSInt &Res = EvalResult.Val.getInt(); 2288 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2289 // TODO: preserve the size expression in declarator info 2290 return Context.getConstantArrayType(VLATy->getElementType(), 2291 Res, ArrayType::Normal, 0); 2292 } 2293 2294 SizeIsNegative = true; 2295 return QualType(); 2296} 2297 2298/// \brief Register the given locally-scoped external C declaration so 2299/// that it can be found later for redeclarations 2300void 2301Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2302 const LookupResult &Previous, 2303 Scope *S) { 2304 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2305 "Decl is not a locally-scoped decl!"); 2306 // Note that we have a locally-scoped external with this name. 2307 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2308 2309 if (!Previous.isSingleResult()) 2310 return; 2311 2312 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2313 2314 // If there was a previous declaration of this variable, it may be 2315 // in our identifier chain. Update the identifier chain with the new 2316 // declaration. 2317 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2318 // The previous declaration was found on the identifer resolver 2319 // chain, so remove it from its scope. 2320 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2321 S = S->getParent(); 2322 2323 if (S) 2324 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2325 } 2326} 2327 2328/// \brief Diagnose function specifiers on a declaration of an identifier that 2329/// does not identify a function. 2330void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2331 // FIXME: We should probably indicate the identifier in question to avoid 2332 // confusion for constructs like "inline int a(), b;" 2333 if (D.getDeclSpec().isInlineSpecified()) 2334 Diag(D.getDeclSpec().getInlineSpecLoc(), 2335 diag::err_inline_non_function); 2336 2337 if (D.getDeclSpec().isVirtualSpecified()) 2338 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2339 diag::err_virtual_non_function); 2340 2341 if (D.getDeclSpec().isExplicitSpecified()) 2342 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2343 diag::err_explicit_non_function); 2344} 2345 2346NamedDecl* 2347Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2348 QualType R, TypeSourceInfo *TInfo, 2349 LookupResult &Previous, bool &Redeclaration) { 2350 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2351 if (D.getCXXScopeSpec().isSet()) { 2352 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2353 << D.getCXXScopeSpec().getRange(); 2354 D.setInvalidType(); 2355 // Pretend we didn't see the scope specifier. 2356 DC = 0; 2357 } 2358 2359 if (getLangOptions().CPlusPlus) { 2360 // Check that there are no default arguments (C++ only). 2361 CheckExtraCXXDefaultArguments(D); 2362 } 2363 2364 DiagnoseFunctionSpecifiers(D); 2365 2366 if (D.getDeclSpec().isThreadSpecified()) 2367 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2368 2369 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2370 if (!NewTD) return 0; 2371 2372 // Handle attributes prior to checking for duplicates in MergeVarDecl 2373 ProcessDeclAttributes(S, NewTD, D); 2374 2375 // Merge the decl with the existing one if appropriate. If the decl is 2376 // in an outer scope, it isn't the same thing. 2377 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2378 if (!Previous.empty()) { 2379 Redeclaration = true; 2380 MergeTypeDefDecl(NewTD, Previous); 2381 } 2382 2383 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2384 // then it shall have block scope. 2385 QualType T = NewTD->getUnderlyingType(); 2386 if (T->isVariablyModifiedType()) { 2387 CurFunctionNeedsScopeChecking = true; 2388 2389 if (S->getFnParent() == 0) { 2390 bool SizeIsNegative; 2391 QualType FixedTy = 2392 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2393 if (!FixedTy.isNull()) { 2394 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2395 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2396 } else { 2397 if (SizeIsNegative) 2398 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2399 else if (T->isVariableArrayType()) 2400 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2401 else 2402 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2403 NewTD->setInvalidDecl(); 2404 } 2405 } 2406 } 2407 2408 // If this is the C FILE type, notify the AST context. 2409 if (IdentifierInfo *II = NewTD->getIdentifier()) 2410 if (!NewTD->isInvalidDecl() && 2411 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2412 if (II->isStr("FILE")) 2413 Context.setFILEDecl(NewTD); 2414 else if (II->isStr("jmp_buf")) 2415 Context.setjmp_bufDecl(NewTD); 2416 else if (II->isStr("sigjmp_buf")) 2417 Context.setsigjmp_bufDecl(NewTD); 2418 } 2419 2420 return NewTD; 2421} 2422 2423/// \brief Determines whether the given declaration is an out-of-scope 2424/// previous declaration. 2425/// 2426/// This routine should be invoked when name lookup has found a 2427/// previous declaration (PrevDecl) that is not in the scope where a 2428/// new declaration by the same name is being introduced. If the new 2429/// declaration occurs in a local scope, previous declarations with 2430/// linkage may still be considered previous declarations (C99 2431/// 6.2.2p4-5, C++ [basic.link]p6). 2432/// 2433/// \param PrevDecl the previous declaration found by name 2434/// lookup 2435/// 2436/// \param DC the context in which the new declaration is being 2437/// declared. 2438/// 2439/// \returns true if PrevDecl is an out-of-scope previous declaration 2440/// for a new delcaration with the same name. 2441static bool 2442isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2443 ASTContext &Context) { 2444 if (!PrevDecl) 2445 return 0; 2446 2447 if (!PrevDecl->hasLinkage()) 2448 return false; 2449 2450 if (Context.getLangOptions().CPlusPlus) { 2451 // C++ [basic.link]p6: 2452 // If there is a visible declaration of an entity with linkage 2453 // having the same name and type, ignoring entities declared 2454 // outside the innermost enclosing namespace scope, the block 2455 // scope declaration declares that same entity and receives the 2456 // linkage of the previous declaration. 2457 DeclContext *OuterContext = DC->getLookupContext(); 2458 if (!OuterContext->isFunctionOrMethod()) 2459 // This rule only applies to block-scope declarations. 2460 return false; 2461 else { 2462 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2463 if (PrevOuterContext->isRecord()) 2464 // We found a member function: ignore it. 2465 return false; 2466 else { 2467 // Find the innermost enclosing namespace for the new and 2468 // previous declarations. 2469 while (!OuterContext->isFileContext()) 2470 OuterContext = OuterContext->getParent(); 2471 while (!PrevOuterContext->isFileContext()) 2472 PrevOuterContext = PrevOuterContext->getParent(); 2473 2474 // The previous declaration is in a different namespace, so it 2475 // isn't the same function. 2476 if (OuterContext->getPrimaryContext() != 2477 PrevOuterContext->getPrimaryContext()) 2478 return false; 2479 } 2480 } 2481 } 2482 2483 return true; 2484} 2485 2486NamedDecl* 2487Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2488 QualType R, TypeSourceInfo *TInfo, 2489 LookupResult &Previous, 2490 MultiTemplateParamsArg TemplateParamLists, 2491 bool &Redeclaration) { 2492 DeclarationName Name = GetNameForDeclarator(D); 2493 2494 // Check that there are no default arguments (C++ only). 2495 if (getLangOptions().CPlusPlus) 2496 CheckExtraCXXDefaultArguments(D); 2497 2498 VarDecl *NewVD; 2499 VarDecl::StorageClass SC; 2500 switch (D.getDeclSpec().getStorageClassSpec()) { 2501 default: assert(0 && "Unknown storage class!"); 2502 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2503 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2504 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2505 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2506 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2507 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2508 case DeclSpec::SCS_mutable: 2509 // mutable can only appear on non-static class members, so it's always 2510 // an error here 2511 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2512 D.setInvalidType(); 2513 SC = VarDecl::None; 2514 break; 2515 } 2516 2517 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2518 if (!II) { 2519 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2520 << Name.getAsString(); 2521 return 0; 2522 } 2523 2524 DiagnoseFunctionSpecifiers(D); 2525 2526 if (!DC->isRecord() && S->getFnParent() == 0) { 2527 // C99 6.9p2: The storage-class specifiers auto and register shall not 2528 // appear in the declaration specifiers in an external declaration. 2529 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2530 2531 // If this is a register variable with an asm label specified, then this 2532 // is a GNU extension. 2533 if (SC == VarDecl::Register && D.getAsmLabel()) 2534 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2535 else 2536 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2537 D.setInvalidType(); 2538 } 2539 } 2540 if (DC->isRecord() && !CurContext->isRecord()) { 2541 // This is an out-of-line definition of a static data member. 2542 if (SC == VarDecl::Static) { 2543 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2544 diag::err_static_out_of_line) 2545 << CodeModificationHint::CreateRemoval( 2546 D.getDeclSpec().getStorageClassSpecLoc()); 2547 } else if (SC == VarDecl::None) 2548 SC = VarDecl::Static; 2549 } 2550 if (SC == VarDecl::Static) { 2551 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2552 if (RD->isLocalClass()) 2553 Diag(D.getIdentifierLoc(), 2554 diag::err_static_data_member_not_allowed_in_local_class) 2555 << Name << RD->getDeclName(); 2556 } 2557 } 2558 2559 // Match up the template parameter lists with the scope specifier, then 2560 // determine whether we have a template or a template specialization. 2561 bool isExplicitSpecialization = false; 2562 if (TemplateParameterList *TemplateParams 2563 = MatchTemplateParametersToScopeSpecifier( 2564 D.getDeclSpec().getSourceRange().getBegin(), 2565 D.getCXXScopeSpec(), 2566 (TemplateParameterList**)TemplateParamLists.get(), 2567 TemplateParamLists.size(), 2568 isExplicitSpecialization)) { 2569 if (TemplateParams->size() > 0) { 2570 // There is no such thing as a variable template. 2571 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2572 << II 2573 << SourceRange(TemplateParams->getTemplateLoc(), 2574 TemplateParams->getRAngleLoc()); 2575 return 0; 2576 } else { 2577 // There is an extraneous 'template<>' for this variable. Complain 2578 // about it, but allow the declaration of the variable. 2579 Diag(TemplateParams->getTemplateLoc(), 2580 diag::err_template_variable_noparams) 2581 << II 2582 << SourceRange(TemplateParams->getTemplateLoc(), 2583 TemplateParams->getRAngleLoc()); 2584 2585 isExplicitSpecialization = true; 2586 } 2587 } 2588 2589 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2590 II, R, TInfo, SC); 2591 2592 if (D.isInvalidType()) 2593 NewVD->setInvalidDecl(); 2594 2595 if (D.getDeclSpec().isThreadSpecified()) { 2596 if (NewVD->hasLocalStorage()) 2597 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2598 else if (!Context.Target.isTLSSupported()) 2599 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2600 else 2601 NewVD->setThreadSpecified(true); 2602 } 2603 2604 // Set the lexical context. If the declarator has a C++ scope specifier, the 2605 // lexical context will be different from the semantic context. 2606 NewVD->setLexicalDeclContext(CurContext); 2607 2608 // Handle attributes prior to checking for duplicates in MergeVarDecl 2609 ProcessDeclAttributes(S, NewVD, D); 2610 2611 // Handle GNU asm-label extension (encoded as an attribute). 2612 if (Expr *E = (Expr*) D.getAsmLabel()) { 2613 // The parser guarantees this is a string. 2614 StringLiteral *SE = cast<StringLiteral>(E); 2615 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2616 } 2617 2618 // Don't consider existing declarations that are in a different 2619 // scope and are out-of-semantic-context declarations (if the new 2620 // declaration has linkage). 2621 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2622 2623 // Merge the decl with the existing one if appropriate. 2624 if (!Previous.empty()) { 2625 if (Previous.isSingleResult() && 2626 isa<FieldDecl>(Previous.getFoundDecl()) && 2627 D.getCXXScopeSpec().isSet()) { 2628 // The user tried to define a non-static data member 2629 // out-of-line (C++ [dcl.meaning]p1). 2630 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2631 << D.getCXXScopeSpec().getRange(); 2632 Previous.clear(); 2633 NewVD->setInvalidDecl(); 2634 } 2635 } else if (D.getCXXScopeSpec().isSet()) { 2636 // No previous declaration in the qualifying scope. 2637 Diag(D.getIdentifierLoc(), diag::err_no_member) 2638 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2639 << D.getCXXScopeSpec().getRange(); 2640 NewVD->setInvalidDecl(); 2641 } 2642 2643 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2644 2645 // This is an explicit specialization of a static data member. Check it. 2646 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2647 CheckMemberSpecialization(NewVD, Previous)) 2648 NewVD->setInvalidDecl(); 2649 2650 // attributes declared post-definition are currently ignored 2651 if (Previous.isSingleResult()) { 2652 const VarDecl *Def = 0; 2653 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2654 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2655 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2656 Diag(Def->getLocation(), diag::note_previous_definition); 2657 } 2658 } 2659 2660 // If this is a locally-scoped extern C variable, update the map of 2661 // such variables. 2662 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2663 !NewVD->isInvalidDecl()) 2664 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2665 2666 return NewVD; 2667} 2668 2669/// \brief Perform semantic checking on a newly-created variable 2670/// declaration. 2671/// 2672/// This routine performs all of the type-checking required for a 2673/// variable declaration once it has been built. It is used both to 2674/// check variables after they have been parsed and their declarators 2675/// have been translated into a declaration, and to check variables 2676/// that have been instantiated from a template. 2677/// 2678/// Sets NewVD->isInvalidDecl() if an error was encountered. 2679void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2680 LookupResult &Previous, 2681 bool &Redeclaration) { 2682 // If the decl is already known invalid, don't check it. 2683 if (NewVD->isInvalidDecl()) 2684 return; 2685 2686 QualType T = NewVD->getType(); 2687 2688 if (T->isObjCInterfaceType()) { 2689 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2690 return NewVD->setInvalidDecl(); 2691 } 2692 2693 // Emit an error if an address space was applied to decl with local storage. 2694 // This includes arrays of objects with address space qualifiers, but not 2695 // automatic variables that point to other address spaces. 2696 // ISO/IEC TR 18037 S5.1.2 2697 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2698 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2699 return NewVD->setInvalidDecl(); 2700 } 2701 2702 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2703 && !NewVD->hasAttr<BlocksAttr>()) 2704 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2705 2706 bool isVM = T->isVariablyModifiedType(); 2707 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2708 NewVD->hasAttr<BlocksAttr>()) 2709 CurFunctionNeedsScopeChecking = true; 2710 2711 if ((isVM && NewVD->hasLinkage()) || 2712 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2713 bool SizeIsNegative; 2714 QualType FixedTy = 2715 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2716 2717 if (FixedTy.isNull() && T->isVariableArrayType()) { 2718 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2719 // FIXME: This won't give the correct result for 2720 // int a[10][n]; 2721 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2722 2723 if (NewVD->isFileVarDecl()) 2724 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2725 << SizeRange; 2726 else if (NewVD->getStorageClass() == VarDecl::Static) 2727 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2728 << SizeRange; 2729 else 2730 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2731 << SizeRange; 2732 return NewVD->setInvalidDecl(); 2733 } 2734 2735 if (FixedTy.isNull()) { 2736 if (NewVD->isFileVarDecl()) 2737 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2738 else 2739 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2740 return NewVD->setInvalidDecl(); 2741 } 2742 2743 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2744 NewVD->setType(FixedTy); 2745 } 2746 2747 if (Previous.empty() && NewVD->isExternC()) { 2748 // Since we did not find anything by this name and we're declaring 2749 // an extern "C" variable, look for a non-visible extern "C" 2750 // declaration with the same name. 2751 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2752 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2753 if (Pos != LocallyScopedExternalDecls.end()) 2754 Previous.addDecl(Pos->second); 2755 } 2756 2757 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2758 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2759 << T; 2760 return NewVD->setInvalidDecl(); 2761 } 2762 2763 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2764 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2765 return NewVD->setInvalidDecl(); 2766 } 2767 2768 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2769 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2770 return NewVD->setInvalidDecl(); 2771 } 2772 2773 if (!Previous.empty()) { 2774 Redeclaration = true; 2775 MergeVarDecl(NewVD, Previous); 2776 } 2777} 2778 2779/// \brief Data used with FindOverriddenMethod 2780struct FindOverriddenMethodData { 2781 Sema *S; 2782 CXXMethodDecl *Method; 2783}; 2784 2785/// \brief Member lookup function that determines whether a given C++ 2786/// method overrides a method in a base class, to be used with 2787/// CXXRecordDecl::lookupInBases(). 2788static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2789 CXXBasePath &Path, 2790 void *UserData) { 2791 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2792 2793 FindOverriddenMethodData *Data 2794 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2795 2796 DeclarationName Name = Data->Method->getDeclName(); 2797 2798 // FIXME: Do we care about other names here too? 2799 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2800 // We really want to find the base class constructor here. 2801 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2802 CanQualType CT = Data->S->Context.getCanonicalType(T); 2803 2804 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2805 } 2806 2807 for (Path.Decls = BaseRecord->lookup(Name); 2808 Path.Decls.first != Path.Decls.second; 2809 ++Path.Decls.first) { 2810 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2811 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2812 return true; 2813 } 2814 } 2815 2816 return false; 2817} 2818 2819/// AddOverriddenMethods - See if a method overrides any in the base classes, 2820/// and if so, check that it's a valid override and remember it. 2821void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2822 // Look for virtual methods in base classes that this method might override. 2823 CXXBasePaths Paths; 2824 FindOverriddenMethodData Data; 2825 Data.Method = MD; 2826 Data.S = this; 2827 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2828 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2829 E = Paths.found_decls_end(); I != E; ++I) { 2830 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2831 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2832 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2833 !CheckOverridingFunctionAttributes(MD, OldMD)) 2834 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2835 } 2836 } 2837 } 2838} 2839 2840NamedDecl* 2841Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2842 QualType R, TypeSourceInfo *TInfo, 2843 LookupResult &Previous, 2844 MultiTemplateParamsArg TemplateParamLists, 2845 bool IsFunctionDefinition, bool &Redeclaration) { 2846 assert(R.getTypePtr()->isFunctionType()); 2847 2848 DeclarationName Name = GetNameForDeclarator(D); 2849 FunctionDecl::StorageClass SC = FunctionDecl::None; 2850 switch (D.getDeclSpec().getStorageClassSpec()) { 2851 default: assert(0 && "Unknown storage class!"); 2852 case DeclSpec::SCS_auto: 2853 case DeclSpec::SCS_register: 2854 case DeclSpec::SCS_mutable: 2855 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2856 diag::err_typecheck_sclass_func); 2857 D.setInvalidType(); 2858 break; 2859 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2860 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2861 case DeclSpec::SCS_static: { 2862 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2863 // C99 6.7.1p5: 2864 // The declaration of an identifier for a function that has 2865 // block scope shall have no explicit storage-class specifier 2866 // other than extern 2867 // See also (C++ [dcl.stc]p4). 2868 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2869 diag::err_static_block_func); 2870 SC = FunctionDecl::None; 2871 } else 2872 SC = FunctionDecl::Static; 2873 break; 2874 } 2875 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2876 } 2877 2878 if (D.getDeclSpec().isThreadSpecified()) 2879 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2880 2881 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2882 bool isInline = D.getDeclSpec().isInlineSpecified(); 2883 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2884 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2885 2886 // Check that the return type is not an abstract class type. 2887 // For record types, this is done by the AbstractClassUsageDiagnoser once 2888 // the class has been completely parsed. 2889 if (!DC->isRecord() && 2890 RequireNonAbstractType(D.getIdentifierLoc(), 2891 R->getAs<FunctionType>()->getResultType(), 2892 diag::err_abstract_type_in_decl, 2893 AbstractReturnType)) 2894 D.setInvalidType(); 2895 2896 // Do not allow returning a objc interface by-value. 2897 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2898 Diag(D.getIdentifierLoc(), 2899 diag::err_object_cannot_be_passed_returned_by_value) << 0 2900 << R->getAs<FunctionType>()->getResultType(); 2901 D.setInvalidType(); 2902 } 2903 2904 bool isVirtualOkay = false; 2905 FunctionDecl *NewFD; 2906 2907 if (isFriend) { 2908 // C++ [class.friend]p5 2909 // A function can be defined in a friend declaration of a 2910 // class . . . . Such a function is implicitly inline. 2911 isInline |= IsFunctionDefinition; 2912 } 2913 2914 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2915 // This is a C++ constructor declaration. 2916 assert(DC->isRecord() && 2917 "Constructors can only be declared in a member context"); 2918 2919 R = CheckConstructorDeclarator(D, R, SC); 2920 2921 // Create the new declaration 2922 NewFD = CXXConstructorDecl::Create(Context, 2923 cast<CXXRecordDecl>(DC), 2924 D.getIdentifierLoc(), Name, R, TInfo, 2925 isExplicit, isInline, 2926 /*isImplicitlyDeclared=*/false); 2927 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2928 // This is a C++ destructor declaration. 2929 if (DC->isRecord()) { 2930 R = CheckDestructorDeclarator(D, SC); 2931 2932 NewFD = CXXDestructorDecl::Create(Context, 2933 cast<CXXRecordDecl>(DC), 2934 D.getIdentifierLoc(), Name, R, 2935 isInline, 2936 /*isImplicitlyDeclared=*/false); 2937 2938 isVirtualOkay = true; 2939 } else { 2940 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2941 2942 // Create a FunctionDecl to satisfy the function definition parsing 2943 // code path. 2944 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2945 Name, R, TInfo, SC, isInline, 2946 /*hasPrototype=*/true); 2947 D.setInvalidType(); 2948 } 2949 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2950 if (!DC->isRecord()) { 2951 Diag(D.getIdentifierLoc(), 2952 diag::err_conv_function_not_member); 2953 return 0; 2954 } 2955 2956 CheckConversionDeclarator(D, R, SC); 2957 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2958 D.getIdentifierLoc(), Name, R, TInfo, 2959 isInline, isExplicit); 2960 2961 isVirtualOkay = true; 2962 } else if (DC->isRecord()) { 2963 // If the of the function is the same as the name of the record, then this 2964 // must be an invalid constructor that has a return type. 2965 // (The parser checks for a return type and makes the declarator a 2966 // constructor if it has no return type). 2967 // must have an invalid constructor that has a return type 2968 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2969 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2970 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2971 << SourceRange(D.getIdentifierLoc()); 2972 return 0; 2973 } 2974 2975 bool isStatic = SC == FunctionDecl::Static; 2976 2977 // [class.free]p1: 2978 // Any allocation function for a class T is a static member 2979 // (even if not explicitly declared static). 2980 if (Name.getCXXOverloadedOperator() == OO_New || 2981 Name.getCXXOverloadedOperator() == OO_Array_New) 2982 isStatic = true; 2983 2984 // [class.free]p6 Any deallocation function for a class X is a static member 2985 // (even if not explicitly declared static). 2986 if (Name.getCXXOverloadedOperator() == OO_Delete || 2987 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2988 isStatic = true; 2989 2990 // This is a C++ method declaration. 2991 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2992 D.getIdentifierLoc(), Name, R, TInfo, 2993 isStatic, isInline); 2994 2995 isVirtualOkay = !isStatic; 2996 } else { 2997 // Determine whether the function was written with a 2998 // prototype. This true when: 2999 // - we're in C++ (where every function has a prototype), 3000 // - there is a prototype in the declarator, or 3001 // - the type R of the function is some kind of typedef or other reference 3002 // to a type name (which eventually refers to a function type). 3003 bool HasPrototype = 3004 getLangOptions().CPlusPlus || 3005 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3006 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3007 3008 NewFD = FunctionDecl::Create(Context, DC, 3009 D.getIdentifierLoc(), 3010 Name, R, TInfo, SC, isInline, HasPrototype); 3011 } 3012 3013 if (D.isInvalidType()) 3014 NewFD->setInvalidDecl(); 3015 3016 // Set the lexical context. If the declarator has a C++ 3017 // scope specifier, or is the object of a friend declaration, the 3018 // lexical context will be different from the semantic context. 3019 NewFD->setLexicalDeclContext(CurContext); 3020 3021 // Match up the template parameter lists with the scope specifier, then 3022 // determine whether we have a template or a template specialization. 3023 FunctionTemplateDecl *FunctionTemplate = 0; 3024 bool isExplicitSpecialization = false; 3025 bool isFunctionTemplateSpecialization = false; 3026 if (TemplateParameterList *TemplateParams 3027 = MatchTemplateParametersToScopeSpecifier( 3028 D.getDeclSpec().getSourceRange().getBegin(), 3029 D.getCXXScopeSpec(), 3030 (TemplateParameterList**)TemplateParamLists.get(), 3031 TemplateParamLists.size(), 3032 isExplicitSpecialization)) { 3033 if (TemplateParams->size() > 0) { 3034 // This is a function template 3035 3036 // Check that we can declare a template here. 3037 if (CheckTemplateDeclScope(S, TemplateParams)) 3038 return 0; 3039 3040 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3041 NewFD->getLocation(), 3042 Name, TemplateParams, 3043 NewFD); 3044 FunctionTemplate->setLexicalDeclContext(CurContext); 3045 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3046 } else { 3047 // This is a function template specialization. 3048 isFunctionTemplateSpecialization = true; 3049 } 3050 3051 // FIXME: Free this memory properly. 3052 TemplateParamLists.release(); 3053 } 3054 3055 // C++ [dcl.fct.spec]p5: 3056 // The virtual specifier shall only be used in declarations of 3057 // nonstatic class member functions that appear within a 3058 // member-specification of a class declaration; see 10.3. 3059 // 3060 if (isVirtual && !NewFD->isInvalidDecl()) { 3061 if (!isVirtualOkay) { 3062 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3063 diag::err_virtual_non_function); 3064 } else if (!CurContext->isRecord()) { 3065 // 'virtual' was specified outside of the class. 3066 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3067 << CodeModificationHint::CreateRemoval( 3068 D.getDeclSpec().getVirtualSpecLoc()); 3069 } else { 3070 // Okay: Add virtual to the method. 3071 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3072 CurClass->setMethodAsVirtual(NewFD); 3073 } 3074 } 3075 3076 // Filter out previous declarations that don't match the scope. 3077 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3078 3079 if (isFriend) { 3080 // DC is the namespace in which the function is being declared. 3081 assert((DC->isFileContext() || !Previous.empty()) && 3082 "previously-undeclared friend function being created " 3083 "in a non-namespace context"); 3084 3085 if (FunctionTemplate) { 3086 FunctionTemplate->setObjectOfFriendDecl( 3087 /* PreviouslyDeclared= */ !Previous.empty()); 3088 FunctionTemplate->setAccess(AS_public); 3089 } 3090 else 3091 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 3092 3093 NewFD->setAccess(AS_public); 3094 } 3095 3096 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3097 !CurContext->isRecord()) { 3098 // C++ [class.static]p1: 3099 // A data or function member of a class may be declared static 3100 // in a class definition, in which case it is a static member of 3101 // the class. 3102 3103 // Complain about the 'static' specifier if it's on an out-of-line 3104 // member function definition. 3105 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3106 diag::err_static_out_of_line) 3107 << CodeModificationHint::CreateRemoval( 3108 D.getDeclSpec().getStorageClassSpecLoc()); 3109 } 3110 3111 // Handle GNU asm-label extension (encoded as an attribute). 3112 if (Expr *E = (Expr*) D.getAsmLabel()) { 3113 // The parser guarantees this is a string. 3114 StringLiteral *SE = cast<StringLiteral>(E); 3115 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 3116 } 3117 3118 // Copy the parameter declarations from the declarator D to the function 3119 // declaration NewFD, if they are available. First scavenge them into Params. 3120 llvm::SmallVector<ParmVarDecl*, 16> Params; 3121 if (D.getNumTypeObjects() > 0) { 3122 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3123 3124 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3125 // function that takes no arguments, not a function that takes a 3126 // single void argument. 3127 // We let through "const void" here because Sema::GetTypeForDeclarator 3128 // already checks for that case. 3129 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3130 FTI.ArgInfo[0].Param && 3131 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3132 // Empty arg list, don't push any params. 3133 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3134 3135 // In C++, the empty parameter-type-list must be spelled "void"; a 3136 // typedef of void is not permitted. 3137 if (getLangOptions().CPlusPlus && 3138 Param->getType().getUnqualifiedType() != Context.VoidTy) 3139 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3140 // FIXME: Leaks decl? 3141 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3142 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3143 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3144 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3145 Param->setDeclContext(NewFD); 3146 Params.push_back(Param); 3147 } 3148 } 3149 3150 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3151 // When we're declaring a function with a typedef, typeof, etc as in the 3152 // following example, we'll need to synthesize (unnamed) 3153 // parameters for use in the declaration. 3154 // 3155 // @code 3156 // typedef void fn(int); 3157 // fn f; 3158 // @endcode 3159 3160 // Synthesize a parameter for each argument type. 3161 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3162 AE = FT->arg_type_end(); AI != AE; ++AI) { 3163 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3164 SourceLocation(), 0, 3165 *AI, /*TInfo=*/0, 3166 VarDecl::None, 0); 3167 Param->setImplicit(); 3168 Params.push_back(Param); 3169 } 3170 } else { 3171 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3172 "Should not need args for typedef of non-prototype fn"); 3173 } 3174 // Finally, we know we have the right number of parameters, install them. 3175 NewFD->setParams(Context, Params.data(), Params.size()); 3176 3177 // If the declarator is a template-id, translate the parser's template 3178 // argument list into our AST format. 3179 bool HasExplicitTemplateArgs = false; 3180 TemplateArgumentListInfo TemplateArgs; 3181 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3182 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3183 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3184 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3185 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3186 TemplateId->getTemplateArgs(), 3187 TemplateId->NumArgs); 3188 translateTemplateArguments(TemplateArgsPtr, 3189 TemplateArgs); 3190 TemplateArgsPtr.release(); 3191 3192 HasExplicitTemplateArgs = true; 3193 3194 if (FunctionTemplate) { 3195 // FIXME: Diagnose function template with explicit template 3196 // arguments. 3197 HasExplicitTemplateArgs = false; 3198 } else if (!isFunctionTemplateSpecialization && 3199 !D.getDeclSpec().isFriendSpecified()) { 3200 // We have encountered something that the user meant to be a 3201 // specialization (because it has explicitly-specified template 3202 // arguments) but that was not introduced with a "template<>" (or had 3203 // too few of them). 3204 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3205 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3206 << CodeModificationHint::CreateInsertion( 3207 D.getDeclSpec().getSourceRange().getBegin(), 3208 "template<> "); 3209 isFunctionTemplateSpecialization = true; 3210 } 3211 } 3212 3213 if (isFunctionTemplateSpecialization) { 3214 if (CheckFunctionTemplateSpecialization(NewFD, 3215 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3216 Previous)) 3217 NewFD->setInvalidDecl(); 3218 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3219 CheckMemberSpecialization(NewFD, Previous)) 3220 NewFD->setInvalidDecl(); 3221 3222 // Perform semantic checking on the function declaration. 3223 bool OverloadableAttrRequired = false; // FIXME: HACK! 3224 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3225 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3226 3227 assert((NewFD->isInvalidDecl() || !Redeclaration || 3228 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3229 "previous declaration set still overloaded"); 3230 3231 // If we have a function template, check the template parameter 3232 // list. This will check and merge default template arguments. 3233 if (FunctionTemplate) { 3234 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3235 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3236 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3237 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3238 : TPC_FunctionTemplate); 3239 } 3240 3241 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3242 // An out-of-line member function declaration must also be a 3243 // definition (C++ [dcl.meaning]p1). 3244 // Note that this is not the case for explicit specializations of 3245 // function templates or member functions of class templates, per 3246 // C++ [temp.expl.spec]p2. 3247 if (!IsFunctionDefinition && !isFriend && 3248 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3249 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3250 << D.getCXXScopeSpec().getRange(); 3251 NewFD->setInvalidDecl(); 3252 } else if (!Redeclaration) { 3253 // The user tried to provide an out-of-line definition for a 3254 // function that is a member of a class or namespace, but there 3255 // was no such member function declared (C++ [class.mfct]p2, 3256 // C++ [namespace.memdef]p2). For example: 3257 // 3258 // class X { 3259 // void f() const; 3260 // }; 3261 // 3262 // void X::f() { } // ill-formed 3263 // 3264 // Complain about this problem, and attempt to suggest close 3265 // matches (e.g., those that differ only in cv-qualifiers and 3266 // whether the parameter types are references). 3267 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3268 << Name << DC << D.getCXXScopeSpec().getRange(); 3269 NewFD->setInvalidDecl(); 3270 3271 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3272 ForRedeclaration); 3273 LookupQualifiedName(Prev, DC); 3274 assert(!Prev.isAmbiguous() && 3275 "Cannot have an ambiguity in previous-declaration lookup"); 3276 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3277 Func != FuncEnd; ++Func) { 3278 if (isa<FunctionDecl>(*Func) && 3279 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3280 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3281 } 3282 } 3283 } 3284 3285 // Handle attributes. We need to have merged decls when handling attributes 3286 // (for example to check for conflicts, etc). 3287 // FIXME: This needs to happen before we merge declarations. Then, 3288 // let attribute merging cope with attribute conflicts. 3289 ProcessDeclAttributes(S, NewFD, D); 3290 3291 // attributes declared post-definition are currently ignored 3292 if (Redeclaration && Previous.isSingleResult()) { 3293 const FunctionDecl *Def; 3294 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3295 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3296 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3297 Diag(Def->getLocation(), diag::note_previous_definition); 3298 } 3299 } 3300 3301 AddKnownFunctionAttributes(NewFD); 3302 3303 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3304 // If a function name is overloadable in C, then every function 3305 // with that name must be marked "overloadable". 3306 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3307 << Redeclaration << NewFD; 3308 if (!Previous.empty()) 3309 Diag(Previous.getRepresentativeDecl()->getLocation(), 3310 diag::note_attribute_overloadable_prev_overload); 3311 NewFD->addAttr(::new (Context) OverloadableAttr()); 3312 } 3313 3314 // If this is a locally-scoped extern C function, update the 3315 // map of such names. 3316 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3317 && !NewFD->isInvalidDecl()) 3318 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3319 3320 // Set this FunctionDecl's range up to the right paren. 3321 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3322 3323 if (FunctionTemplate && NewFD->isInvalidDecl()) 3324 FunctionTemplate->setInvalidDecl(); 3325 3326 if (FunctionTemplate) 3327 return FunctionTemplate; 3328 3329 return NewFD; 3330} 3331 3332/// \brief Perform semantic checking of a new function declaration. 3333/// 3334/// Performs semantic analysis of the new function declaration 3335/// NewFD. This routine performs all semantic checking that does not 3336/// require the actual declarator involved in the declaration, and is 3337/// used both for the declaration of functions as they are parsed 3338/// (called via ActOnDeclarator) and for the declaration of functions 3339/// that have been instantiated via C++ template instantiation (called 3340/// via InstantiateDecl). 3341/// 3342/// \param IsExplicitSpecialiation whether this new function declaration is 3343/// an explicit specialization of the previous declaration. 3344/// 3345/// This sets NewFD->isInvalidDecl() to true if there was an error. 3346void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3347 LookupResult &Previous, 3348 bool IsExplicitSpecialization, 3349 bool &Redeclaration, 3350 bool &OverloadableAttrRequired) { 3351 // If NewFD is already known erroneous, don't do any of this checking. 3352 if (NewFD->isInvalidDecl()) 3353 return; 3354 3355 if (NewFD->getResultType()->isVariablyModifiedType()) { 3356 // Functions returning a variably modified type violate C99 6.7.5.2p2 3357 // because all functions have linkage. 3358 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3359 return NewFD->setInvalidDecl(); 3360 } 3361 3362 if (NewFD->isMain()) 3363 CheckMain(NewFD); 3364 3365 // Check for a previous declaration of this name. 3366 if (Previous.empty() && NewFD->isExternC()) { 3367 // Since we did not find anything by this name and we're declaring 3368 // an extern "C" function, look for a non-visible extern "C" 3369 // declaration with the same name. 3370 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3371 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3372 if (Pos != LocallyScopedExternalDecls.end()) 3373 Previous.addDecl(Pos->second); 3374 } 3375 3376 // Merge or overload the declaration with an existing declaration of 3377 // the same name, if appropriate. 3378 if (!Previous.empty()) { 3379 // Determine whether NewFD is an overload of PrevDecl or 3380 // a declaration that requires merging. If it's an overload, 3381 // there's no more work to do here; we'll just add the new 3382 // function to the scope. 3383 3384 NamedDecl *OldDecl = 0; 3385 if (!AllowOverloadingOfFunction(Previous, Context)) { 3386 Redeclaration = true; 3387 OldDecl = Previous.getFoundDecl(); 3388 } else { 3389 if (!getLangOptions().CPlusPlus) { 3390 OverloadableAttrRequired = true; 3391 3392 // Functions marked "overloadable" must have a prototype (that 3393 // we can't get through declaration merging). 3394 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3395 Diag(NewFD->getLocation(), 3396 diag::err_attribute_overloadable_no_prototype) 3397 << NewFD; 3398 Redeclaration = true; 3399 3400 // Turn this into a variadic function with no parameters. 3401 QualType R = Context.getFunctionType( 3402 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3403 0, 0, true, 0); 3404 NewFD->setType(R); 3405 return NewFD->setInvalidDecl(); 3406 } 3407 } 3408 3409 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3410 case Ovl_Match: 3411 Redeclaration = true; 3412 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3413 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3414 Redeclaration = false; 3415 } 3416 break; 3417 3418 case Ovl_NonFunction: 3419 Redeclaration = true; 3420 break; 3421 3422 case Ovl_Overload: 3423 Redeclaration = false; 3424 break; 3425 } 3426 } 3427 3428 if (Redeclaration) { 3429 // NewFD and OldDecl represent declarations that need to be 3430 // merged. 3431 if (MergeFunctionDecl(NewFD, OldDecl)) 3432 return NewFD->setInvalidDecl(); 3433 3434 Previous.clear(); 3435 Previous.addDecl(OldDecl); 3436 3437 if (FunctionTemplateDecl *OldTemplateDecl 3438 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3439 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3440 FunctionTemplateDecl *NewTemplateDecl 3441 = NewFD->getDescribedFunctionTemplate(); 3442 assert(NewTemplateDecl && "Template/non-template mismatch"); 3443 if (CXXMethodDecl *Method 3444 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3445 Method->setAccess(OldTemplateDecl->getAccess()); 3446 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3447 } 3448 3449 // If this is an explicit specialization of a member that is a function 3450 // template, mark it as a member specialization. 3451 if (IsExplicitSpecialization && 3452 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3453 NewTemplateDecl->setMemberSpecialization(); 3454 assert(OldTemplateDecl->isMemberSpecialization()); 3455 } 3456 } else { 3457 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3458 NewFD->setAccess(OldDecl->getAccess()); 3459 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3460 } 3461 } 3462 } 3463 3464 // Semantic checking for this function declaration (in isolation). 3465 if (getLangOptions().CPlusPlus) { 3466 // C++-specific checks. 3467 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3468 CheckConstructor(Constructor); 3469 } else if (CXXDestructorDecl *Destructor = 3470 dyn_cast<CXXDestructorDecl>(NewFD)) { 3471 CXXRecordDecl *Record = Destructor->getParent(); 3472 QualType ClassType = Context.getTypeDeclType(Record); 3473 3474 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3475 // type is dependent? Both gcc and edg can handle that. 3476 if (!ClassType->isDependentType()) { 3477 DeclarationName Name 3478 = Context.DeclarationNames.getCXXDestructorName( 3479 Context.getCanonicalType(ClassType)); 3480 if (NewFD->getDeclName() != Name) { 3481 Diag(NewFD->getLocation(), diag::err_destructor_name); 3482 return NewFD->setInvalidDecl(); 3483 } 3484 } 3485 3486 Record->setUserDeclaredDestructor(true); 3487 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3488 // user-defined destructor. 3489 Record->setPOD(false); 3490 3491 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3492 // declared destructor. 3493 // FIXME: C++0x: don't do this for "= default" destructors 3494 Record->setHasTrivialDestructor(false); 3495 } else if (CXXConversionDecl *Conversion 3496 = dyn_cast<CXXConversionDecl>(NewFD)) { 3497 ActOnConversionDeclarator(Conversion); 3498 } 3499 3500 // Find any virtual functions that this function overrides. 3501 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3502 if (!Method->isFunctionTemplateSpecialization() && 3503 !Method->getDescribedFunctionTemplate()) 3504 AddOverriddenMethods(Method->getParent(), Method); 3505 } 3506 3507 // Additional checks for the destructor; make sure we do this after we 3508 // figure out whether the destructor is virtual. 3509 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3510 if (!Destructor->getParent()->isDependentType()) 3511 CheckDestructor(Destructor); 3512 3513 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3514 if (NewFD->isOverloadedOperator() && 3515 CheckOverloadedOperatorDeclaration(NewFD)) 3516 return NewFD->setInvalidDecl(); 3517 3518 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3519 if (NewFD->getLiteralIdentifier() && 3520 CheckLiteralOperatorDeclaration(NewFD)) 3521 return NewFD->setInvalidDecl(); 3522 3523 // In C++, check default arguments now that we have merged decls. Unless 3524 // the lexical context is the class, because in this case this is done 3525 // during delayed parsing anyway. 3526 if (!CurContext->isRecord()) 3527 CheckCXXDefaultArguments(NewFD); 3528 } 3529} 3530 3531void Sema::CheckMain(FunctionDecl* FD) { 3532 // C++ [basic.start.main]p3: A program that declares main to be inline 3533 // or static is ill-formed. 3534 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3535 // shall not appear in a declaration of main. 3536 // static main is not an error under C99, but we should warn about it. 3537 bool isInline = FD->isInlineSpecified(); 3538 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3539 if (isInline || isStatic) { 3540 unsigned diagID = diag::warn_unusual_main_decl; 3541 if (isInline || getLangOptions().CPlusPlus) 3542 diagID = diag::err_unusual_main_decl; 3543 3544 int which = isStatic + (isInline << 1) - 1; 3545 Diag(FD->getLocation(), diagID) << which; 3546 } 3547 3548 QualType T = FD->getType(); 3549 assert(T->isFunctionType() && "function decl is not of function type"); 3550 const FunctionType* FT = T->getAs<FunctionType>(); 3551 3552 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3553 // TODO: add a replacement fixit to turn the return type into 'int'. 3554 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3555 FD->setInvalidDecl(true); 3556 } 3557 3558 // Treat protoless main() as nullary. 3559 if (isa<FunctionNoProtoType>(FT)) return; 3560 3561 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3562 unsigned nparams = FTP->getNumArgs(); 3563 assert(FD->getNumParams() == nparams); 3564 3565 bool HasExtraParameters = (nparams > 3); 3566 3567 // Darwin passes an undocumented fourth argument of type char**. If 3568 // other platforms start sprouting these, the logic below will start 3569 // getting shifty. 3570 if (nparams == 4 && 3571 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3572 HasExtraParameters = false; 3573 3574 if (HasExtraParameters) { 3575 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3576 FD->setInvalidDecl(true); 3577 nparams = 3; 3578 } 3579 3580 // FIXME: a lot of the following diagnostics would be improved 3581 // if we had some location information about types. 3582 3583 QualType CharPP = 3584 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3585 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3586 3587 for (unsigned i = 0; i < nparams; ++i) { 3588 QualType AT = FTP->getArgType(i); 3589 3590 bool mismatch = true; 3591 3592 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3593 mismatch = false; 3594 else if (Expected[i] == CharPP) { 3595 // As an extension, the following forms are okay: 3596 // char const ** 3597 // char const * const * 3598 // char * const * 3599 3600 QualifierCollector qs; 3601 const PointerType* PT; 3602 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3603 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3604 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3605 qs.removeConst(); 3606 mismatch = !qs.empty(); 3607 } 3608 } 3609 3610 if (mismatch) { 3611 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3612 // TODO: suggest replacing given type with expected type 3613 FD->setInvalidDecl(true); 3614 } 3615 } 3616 3617 if (nparams == 1 && !FD->isInvalidDecl()) { 3618 Diag(FD->getLocation(), diag::warn_main_one_arg); 3619 } 3620} 3621 3622bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3623 // FIXME: Need strict checking. In C89, we need to check for 3624 // any assignment, increment, decrement, function-calls, or 3625 // commas outside of a sizeof. In C99, it's the same list, 3626 // except that the aforementioned are allowed in unevaluated 3627 // expressions. Everything else falls under the 3628 // "may accept other forms of constant expressions" exception. 3629 // (We never end up here for C++, so the constant expression 3630 // rules there don't matter.) 3631 if (Init->isConstantInitializer(Context)) 3632 return false; 3633 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3634 << Init->getSourceRange(); 3635 return true; 3636} 3637 3638void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3639 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3640} 3641 3642/// AddInitializerToDecl - Adds the initializer Init to the 3643/// declaration dcl. If DirectInit is true, this is C++ direct 3644/// initialization rather than copy initialization. 3645void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3646 Decl *RealDecl = dcl.getAs<Decl>(); 3647 // If there is no declaration, there was an error parsing it. Just ignore 3648 // the initializer. 3649 if (RealDecl == 0) 3650 return; 3651 3652 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3653 // With declarators parsed the way they are, the parser cannot 3654 // distinguish between a normal initializer and a pure-specifier. 3655 // Thus this grotesque test. 3656 IntegerLiteral *IL; 3657 Expr *Init = static_cast<Expr *>(init.get()); 3658 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3659 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3660 CheckPureMethod(Method, Init->getSourceRange()); 3661 else { 3662 Diag(Method->getLocation(), diag::err_member_function_initialization) 3663 << Method->getDeclName() << Init->getSourceRange(); 3664 Method->setInvalidDecl(); 3665 } 3666 return; 3667 } 3668 3669 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3670 if (!VDecl) { 3671 if (getLangOptions().CPlusPlus && 3672 RealDecl->getLexicalDeclContext()->isRecord() && 3673 isa<NamedDecl>(RealDecl)) 3674 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3675 << cast<NamedDecl>(RealDecl)->getDeclName(); 3676 else 3677 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3678 RealDecl->setInvalidDecl(); 3679 return; 3680 } 3681 3682 // A definition must end up with a complete type, which means it must be 3683 // complete with the restriction that an array type might be completed by the 3684 // initializer; note that later code assumes this restriction. 3685 QualType BaseDeclType = VDecl->getType(); 3686 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3687 BaseDeclType = Array->getElementType(); 3688 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3689 diag::err_typecheck_decl_incomplete_type)) { 3690 RealDecl->setInvalidDecl(); 3691 return; 3692 } 3693 3694 // The variable can not have an abstract class type. 3695 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3696 diag::err_abstract_type_in_decl, 3697 AbstractVariableType)) 3698 VDecl->setInvalidDecl(); 3699 3700 const VarDecl *Def = 0; 3701 if (VDecl->getDefinition(Def)) { 3702 Diag(VDecl->getLocation(), diag::err_redefinition) 3703 << VDecl->getDeclName(); 3704 Diag(Def->getLocation(), diag::note_previous_definition); 3705 VDecl->setInvalidDecl(); 3706 return; 3707 } 3708 3709 // Take ownership of the expression, now that we're sure we have somewhere 3710 // to put it. 3711 Expr *Init = init.takeAs<Expr>(); 3712 assert(Init && "missing initializer"); 3713 3714 // Capture the variable that is being initialized and the style of 3715 // initialization. 3716 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3717 3718 // FIXME: Poor source location information. 3719 InitializationKind Kind 3720 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3721 Init->getLocStart(), 3722 Init->getLocEnd()) 3723 : InitializationKind::CreateCopy(VDecl->getLocation(), 3724 Init->getLocStart()); 3725 3726 // Get the decls type and save a reference for later, since 3727 // CheckInitializerTypes may change it. 3728 QualType DclT = VDecl->getType(), SavT = DclT; 3729 if (VDecl->isBlockVarDecl()) { 3730 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3731 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3732 VDecl->setInvalidDecl(); 3733 } else if (!VDecl->isInvalidDecl()) { 3734 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3735 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3736 MultiExprArg(*this, (void**)&Init, 1), 3737 &DclT); 3738 if (Result.isInvalid()) { 3739 VDecl->setInvalidDecl(); 3740 return; 3741 } 3742 3743 Init = Result.takeAs<Expr>(); 3744 3745 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3746 // Don't check invalid declarations to avoid emitting useless diagnostics. 3747 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3748 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3749 CheckForConstantInitializer(Init, DclT); 3750 } 3751 } 3752 } else if (VDecl->isStaticDataMember() && 3753 VDecl->getLexicalDeclContext()->isRecord()) { 3754 // This is an in-class initialization for a static data member, e.g., 3755 // 3756 // struct S { 3757 // static const int value = 17; 3758 // }; 3759 3760 // Attach the initializer 3761 VDecl->setInit(Context, Init); 3762 3763 // C++ [class.mem]p4: 3764 // A member-declarator can contain a constant-initializer only 3765 // if it declares a static member (9.4) of const integral or 3766 // const enumeration type, see 9.4.2. 3767 QualType T = VDecl->getType(); 3768 if (!T->isDependentType() && 3769 (!Context.getCanonicalType(T).isConstQualified() || 3770 !T->isIntegralType())) { 3771 Diag(VDecl->getLocation(), diag::err_member_initialization) 3772 << VDecl->getDeclName() << Init->getSourceRange(); 3773 VDecl->setInvalidDecl(); 3774 } else { 3775 // C++ [class.static.data]p4: 3776 // If a static data member is of const integral or const 3777 // enumeration type, its declaration in the class definition 3778 // can specify a constant-initializer which shall be an 3779 // integral constant expression (5.19). 3780 if (!Init->isTypeDependent() && 3781 !Init->getType()->isIntegralType()) { 3782 // We have a non-dependent, non-integral or enumeration type. 3783 Diag(Init->getSourceRange().getBegin(), 3784 diag::err_in_class_initializer_non_integral_type) 3785 << Init->getType() << Init->getSourceRange(); 3786 VDecl->setInvalidDecl(); 3787 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3788 // Check whether the expression is a constant expression. 3789 llvm::APSInt Value; 3790 SourceLocation Loc; 3791 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3792 Diag(Loc, diag::err_in_class_initializer_non_constant) 3793 << Init->getSourceRange(); 3794 VDecl->setInvalidDecl(); 3795 } else if (!VDecl->getType()->isDependentType()) 3796 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3797 } 3798 } 3799 } else if (VDecl->isFileVarDecl()) { 3800 if (VDecl->getStorageClass() == VarDecl::Extern) 3801 Diag(VDecl->getLocation(), diag::warn_extern_init); 3802 if (!VDecl->isInvalidDecl()) { 3803 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3804 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3805 MultiExprArg(*this, (void**)&Init, 1), 3806 &DclT); 3807 if (Result.isInvalid()) { 3808 VDecl->setInvalidDecl(); 3809 return; 3810 } 3811 3812 Init = Result.takeAs<Expr>(); 3813 } 3814 3815 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3816 // Don't check invalid declarations to avoid emitting useless diagnostics. 3817 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3818 // C99 6.7.8p4. All file scoped initializers need to be constant. 3819 CheckForConstantInitializer(Init, DclT); 3820 } 3821 } 3822 // If the type changed, it means we had an incomplete type that was 3823 // completed by the initializer. For example: 3824 // int ary[] = { 1, 3, 5 }; 3825 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3826 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3827 VDecl->setType(DclT); 3828 Init->setType(DclT); 3829 } 3830 3831 Init = MaybeCreateCXXExprWithTemporaries(Init); 3832 // Attach the initializer to the decl. 3833 VDecl->setInit(Context, Init); 3834 3835 // If the previous declaration of VDecl was a tentative definition, 3836 // remove it from the set of tentative definitions. 3837 if (VDecl->getPreviousDeclaration() && 3838 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3839 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3840 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3841 } 3842 3843 if (getLangOptions().CPlusPlus) { 3844 // Make sure we mark the destructor as used if necessary. 3845 QualType InitType = VDecl->getType(); 3846 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3847 InitType = Context.getBaseElementType(Array); 3848 if (InitType->isRecordType()) 3849 FinalizeVarWithDestructor(VDecl, InitType); 3850 } 3851 3852 return; 3853} 3854 3855void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3856 bool TypeContainsUndeducedAuto) { 3857 Decl *RealDecl = dcl.getAs<Decl>(); 3858 3859 // If there is no declaration, there was an error parsing it. Just ignore it. 3860 if (RealDecl == 0) 3861 return; 3862 3863 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3864 QualType Type = Var->getType(); 3865 3866 // Record tentative definitions. 3867 if (Var->isTentativeDefinition(Context)) { 3868 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3869 InsertPair = 3870 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3871 3872 // Keep the latest definition in the map. If we see 'int i; int i;' we 3873 // want the second one in the map. 3874 InsertPair.first->second = Var; 3875 3876 // However, for the list, we don't care about the order, just make sure 3877 // that there are no dupes for a given declaration name. 3878 if (InsertPair.second) 3879 TentativeDefinitionList.push_back(Var->getDeclName()); 3880 } 3881 3882 // C++ [dcl.init.ref]p3: 3883 // The initializer can be omitted for a reference only in a 3884 // parameter declaration (8.3.5), in the declaration of a 3885 // function return type, in the declaration of a class member 3886 // within its class declaration (9.2), and where the extern 3887 // specifier is explicitly used. 3888 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3889 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3890 << Var->getDeclName() 3891 << SourceRange(Var->getLocation(), Var->getLocation()); 3892 Var->setInvalidDecl(); 3893 return; 3894 } 3895 3896 // C++0x [dcl.spec.auto]p3 3897 if (TypeContainsUndeducedAuto) { 3898 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3899 << Var->getDeclName() << Type; 3900 Var->setInvalidDecl(); 3901 return; 3902 } 3903 3904 // An array without size is an incomplete type, and there are no special 3905 // rules in C++ to make such a definition acceptable. 3906 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3907 !Var->hasExternalStorage()) { 3908 Diag(Var->getLocation(), 3909 diag::err_typecheck_incomplete_array_needs_initializer); 3910 Var->setInvalidDecl(); 3911 return; 3912 } 3913 3914 // C++ [temp.expl.spec]p15: 3915 // An explicit specialization of a static data member of a template is a 3916 // definition if the declaration includes an initializer; otherwise, it 3917 // is a declaration. 3918 if (Var->isStaticDataMember() && 3919 Var->getInstantiatedFromStaticDataMember() && 3920 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3921 return; 3922 3923 // C++ [dcl.init]p9: 3924 // If no initializer is specified for an object, and the object 3925 // is of (possibly cv-qualified) non-POD class type (or array 3926 // thereof), the object shall be default-initialized; if the 3927 // object is of const-qualified type, the underlying class type 3928 // shall have a user-declared default constructor. 3929 // 3930 // FIXME: Diagnose the "user-declared default constructor" bit. 3931 if (getLangOptions().CPlusPlus) { 3932 QualType InitType = Type; 3933 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3934 InitType = Context.getBaseElementType(Array); 3935 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3936 InitType->isRecordType() && !InitType->isDependentType()) { 3937 if (!RequireCompleteType(Var->getLocation(), InitType, 3938 diag::err_invalid_incomplete_type_use)) { 3939 InitializedEntity Entity 3940 = InitializedEntity::InitializeVariable(Var); 3941 InitializationKind Kind 3942 = InitializationKind::CreateDefault(Var->getLocation()); 3943 3944 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 3945 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 3946 MultiExprArg(*this, 0, 0)); 3947 if (Init.isInvalid()) 3948 Var->setInvalidDecl(); 3949 else { 3950 Var->setInit(Context, 3951 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 3952 FinalizeVarWithDestructor(Var, InitType); 3953 } 3954 } else { 3955 Var->setInvalidDecl(); 3956 } 3957 } 3958 3959 // The variable can not have an abstract class type. 3960 if (RequireNonAbstractType(Var->getLocation(), Type, 3961 diag::err_abstract_type_in_decl, 3962 AbstractVariableType)) 3963 Var->setInvalidDecl(); 3964 } 3965 3966#if 0 3967 // FIXME: Temporarily disabled because we are not properly parsing 3968 // linkage specifications on declarations, e.g., 3969 // 3970 // extern "C" const CGPoint CGPointerZero; 3971 // 3972 // C++ [dcl.init]p9: 3973 // 3974 // If no initializer is specified for an object, and the 3975 // object is of (possibly cv-qualified) non-POD class type (or 3976 // array thereof), the object shall be default-initialized; if 3977 // the object is of const-qualified type, the underlying class 3978 // type shall have a user-declared default 3979 // constructor. Otherwise, if no initializer is specified for 3980 // an object, the object and its subobjects, if any, have an 3981 // indeterminate initial value; if the object or any of its 3982 // subobjects are of const-qualified type, the program is 3983 // ill-formed. 3984 // 3985 // This isn't technically an error in C, so we don't diagnose it. 3986 // 3987 // FIXME: Actually perform the POD/user-defined default 3988 // constructor check. 3989 if (getLangOptions().CPlusPlus && 3990 Context.getCanonicalType(Type).isConstQualified() && 3991 !Var->hasExternalStorage()) 3992 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3993 << Var->getName() 3994 << SourceRange(Var->getLocation(), Var->getLocation()); 3995#endif 3996 } 3997} 3998 3999Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4000 DeclPtrTy *Group, 4001 unsigned NumDecls) { 4002 llvm::SmallVector<Decl*, 8> Decls; 4003 4004 if (DS.isTypeSpecOwned()) 4005 Decls.push_back((Decl*)DS.getTypeRep()); 4006 4007 for (unsigned i = 0; i != NumDecls; ++i) 4008 if (Decl *D = Group[i].getAs<Decl>()) 4009 Decls.push_back(D); 4010 4011 // Perform semantic analysis that depends on having fully processed both 4012 // the declarator and initializer. 4013 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 4014 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 4015 if (!IDecl) 4016 continue; 4017 QualType T = IDecl->getType(); 4018 4019 // Block scope. C99 6.7p7: If an identifier for an object is declared with 4020 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 4021 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 4022 if (T->isDependentType()) { 4023 // If T is dependent, we should not require a complete type. 4024 // (RequireCompleteType shouldn't be called with dependent types.) 4025 // But we still can at least check if we've got an array of unspecified 4026 // size without an initializer. 4027 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 4028 !IDecl->getInit()) { 4029 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 4030 << T; 4031 IDecl->setInvalidDecl(); 4032 } 4033 } else if (!IDecl->isInvalidDecl()) { 4034 // If T is an incomplete array type with an initializer list that is 4035 // dependent on something, its size has not been fixed. We could attempt 4036 // to fix the size for such arrays, but we would still have to check 4037 // here for initializers containing a C++0x vararg expansion, e.g. 4038 // template <typename... Args> void f(Args... args) { 4039 // int vals[] = { args }; 4040 // } 4041 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 4042 Expr *Init = IDecl->getInit(); 4043 if (IAT && Init && 4044 (Init->isTypeDependent() || Init->isValueDependent())) { 4045 // Check that the member type of the array is complete, at least. 4046 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 4047 diag::err_typecheck_decl_incomplete_type)) 4048 IDecl->setInvalidDecl(); 4049 } else if (RequireCompleteType(IDecl->getLocation(), T, 4050 diag::err_typecheck_decl_incomplete_type)) 4051 IDecl->setInvalidDecl(); 4052 } 4053 } 4054 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4055 // object that has file scope without an initializer, and without a 4056 // storage-class specifier or with the storage-class specifier "static", 4057 // constitutes a tentative definition. Note: A tentative definition with 4058 // external linkage is valid (C99 6.2.2p5). 4059 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 4060 if (const IncompleteArrayType *ArrayT 4061 = Context.getAsIncompleteArrayType(T)) { 4062 if (RequireCompleteType(IDecl->getLocation(), 4063 ArrayT->getElementType(), 4064 diag::err_illegal_decl_array_incomplete_type)) 4065 IDecl->setInvalidDecl(); 4066 } else if (IDecl->getStorageClass() == VarDecl::Static) { 4067 // C99 6.9.2p3: If the declaration of an identifier for an object is 4068 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4069 // declared type shall not be an incomplete type. 4070 // NOTE: code such as the following 4071 // static struct s; 4072 // struct s { int a; }; 4073 // is accepted by gcc. Hence here we issue a warning instead of 4074 // an error and we do not invalidate the static declaration. 4075 // NOTE: to avoid multiple warnings, only check the first declaration. 4076 if (IDecl->getPreviousDeclaration() == 0) 4077 RequireCompleteType(IDecl->getLocation(), T, 4078 diag::ext_typecheck_decl_incomplete_type); 4079 } 4080 } 4081 } 4082 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4083 Decls.data(), Decls.size())); 4084} 4085 4086 4087/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4088/// to introduce parameters into function prototype scope. 4089Sema::DeclPtrTy 4090Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4091 const DeclSpec &DS = D.getDeclSpec(); 4092 4093 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4094 VarDecl::StorageClass StorageClass = VarDecl::None; 4095 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4096 StorageClass = VarDecl::Register; 4097 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4098 Diag(DS.getStorageClassSpecLoc(), 4099 diag::err_invalid_storage_class_in_func_decl); 4100 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4101 } 4102 4103 if (D.getDeclSpec().isThreadSpecified()) 4104 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4105 4106 DiagnoseFunctionSpecifiers(D); 4107 4108 // Check that there are no default arguments inside the type of this 4109 // parameter (C++ only). 4110 if (getLangOptions().CPlusPlus) 4111 CheckExtraCXXDefaultArguments(D); 4112 4113 TypeSourceInfo *TInfo = 0; 4114 TagDecl *OwnedDecl = 0; 4115 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4116 4117 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4118 // C++ [dcl.fct]p6: 4119 // Types shall not be defined in return or parameter types. 4120 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4121 << Context.getTypeDeclType(OwnedDecl); 4122 } 4123 4124 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 4125 // Can this happen for params? We already checked that they don't conflict 4126 // among each other. Here they can only shadow globals, which is ok. 4127 IdentifierInfo *II = D.getIdentifier(); 4128 if (II) { 4129 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 4130 if (PrevDecl->isTemplateParameter()) { 4131 // Maybe we will complain about the shadowed template parameter. 4132 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4133 // Just pretend that we didn't see the previous declaration. 4134 PrevDecl = 0; 4135 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4136 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4137 4138 // Recover by removing the name 4139 II = 0; 4140 D.SetIdentifier(0, D.getIdentifierLoc()); 4141 } 4142 } 4143 } 4144 4145 // Parameters can not be abstract class types. 4146 // For record types, this is done by the AbstractClassUsageDiagnoser once 4147 // the class has been completely parsed. 4148 if (!CurContext->isRecord() && 4149 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4150 diag::err_abstract_type_in_decl, 4151 AbstractParamType)) 4152 D.setInvalidType(true); 4153 4154 QualType T = adjustParameterType(parmDeclType); 4155 4156 ParmVarDecl *New 4157 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 4158 T, TInfo, StorageClass, 0); 4159 4160 if (D.isInvalidType()) 4161 New->setInvalidDecl(); 4162 4163 // Parameter declarators cannot be interface types. All ObjC objects are 4164 // passed by reference. 4165 if (T->isObjCInterfaceType()) { 4166 Diag(D.getIdentifierLoc(), 4167 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4168 New->setInvalidDecl(); 4169 } 4170 4171 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4172 if (D.getCXXScopeSpec().isSet()) { 4173 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4174 << D.getCXXScopeSpec().getRange(); 4175 New->setInvalidDecl(); 4176 } 4177 4178 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4179 // duration shall not be qualified by an address-space qualifier." 4180 // Since all parameters have automatic store duration, they can not have 4181 // an address space. 4182 if (T.getAddressSpace() != 0) { 4183 Diag(D.getIdentifierLoc(), 4184 diag::err_arg_with_address_space); 4185 New->setInvalidDecl(); 4186 } 4187 4188 4189 // Add the parameter declaration into this scope. 4190 S->AddDecl(DeclPtrTy::make(New)); 4191 if (II) 4192 IdResolver.AddDecl(New); 4193 4194 ProcessDeclAttributes(S, New, D); 4195 4196 if (New->hasAttr<BlocksAttr>()) { 4197 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4198 } 4199 return DeclPtrTy::make(New); 4200} 4201 4202void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4203 SourceLocation LocAfterDecls) { 4204 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4205 "Not a function declarator!"); 4206 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4207 4208 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4209 // for a K&R function. 4210 if (!FTI.hasPrototype) { 4211 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4212 --i; 4213 if (FTI.ArgInfo[i].Param == 0) { 4214 llvm::SmallString<256> Code; 4215 llvm::raw_svector_ostream(Code) << " int " 4216 << FTI.ArgInfo[i].Ident->getName() 4217 << ";\n"; 4218 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4219 << FTI.ArgInfo[i].Ident 4220 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4221 4222 // Implicitly declare the argument as type 'int' for lack of a better 4223 // type. 4224 DeclSpec DS; 4225 const char* PrevSpec; // unused 4226 unsigned DiagID; // unused 4227 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4228 PrevSpec, DiagID); 4229 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4230 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4231 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4232 } 4233 } 4234 } 4235} 4236 4237Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4238 Declarator &D) { 4239 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4240 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4241 "Not a function declarator!"); 4242 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4243 4244 if (FTI.hasPrototype) { 4245 // FIXME: Diagnose arguments without names in C. 4246 } 4247 4248 Scope *ParentScope = FnBodyScope->getParent(); 4249 4250 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4251 MultiTemplateParamsArg(*this), 4252 /*IsFunctionDefinition=*/true); 4253 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4254} 4255 4256static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4257 // Don't warn about invalid declarations. 4258 if (FD->isInvalidDecl()) 4259 return false; 4260 4261 // Or declarations that aren't global. 4262 if (!FD->isGlobal()) 4263 return false; 4264 4265 // Don't warn about C++ member functions. 4266 if (isa<CXXMethodDecl>(FD)) 4267 return false; 4268 4269 // Don't warn about 'main'. 4270 if (FD->isMain()) 4271 return false; 4272 4273 // Don't warn about inline functions. 4274 if (FD->isInlineSpecified()) 4275 return false; 4276 4277 // Don't warn about function templates. 4278 if (FD->getDescribedFunctionTemplate()) 4279 return false; 4280 4281 // Don't warn about function template specializations. 4282 if (FD->isFunctionTemplateSpecialization()) 4283 return false; 4284 4285 bool MissingPrototype = true; 4286 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4287 Prev; Prev = Prev->getPreviousDeclaration()) { 4288 // Ignore any declarations that occur in function or method 4289 // scope, because they aren't visible from the header. 4290 if (Prev->getDeclContext()->isFunctionOrMethod()) 4291 continue; 4292 4293 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4294 break; 4295 } 4296 4297 return MissingPrototype; 4298} 4299 4300Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4301 // Clear the last template instantiation error context. 4302 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4303 4304 if (!D) 4305 return D; 4306 FunctionDecl *FD = 0; 4307 4308 if (FunctionTemplateDecl *FunTmpl 4309 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4310 FD = FunTmpl->getTemplatedDecl(); 4311 else 4312 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4313 4314 CurFunctionNeedsScopeChecking = false; 4315 4316 // See if this is a redefinition. 4317 const FunctionDecl *Definition; 4318 if (FD->getBody(Definition)) { 4319 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4320 Diag(Definition->getLocation(), diag::note_previous_definition); 4321 } 4322 4323 // Builtin functions cannot be defined. 4324 if (unsigned BuiltinID = FD->getBuiltinID()) { 4325 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4326 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4327 FD->setInvalidDecl(); 4328 } 4329 } 4330 4331 // The return type of a function definition must be complete 4332 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4333 QualType ResultType = FD->getResultType(); 4334 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4335 !FD->isInvalidDecl() && 4336 RequireCompleteType(FD->getLocation(), ResultType, 4337 diag::err_func_def_incomplete_result)) 4338 FD->setInvalidDecl(); 4339 4340 // GNU warning -Wmissing-prototypes: 4341 // Warn if a global function is defined without a previous 4342 // prototype declaration. This warning is issued even if the 4343 // definition itself provides a prototype. The aim is to detect 4344 // global functions that fail to be declared in header files. 4345 if (ShouldWarnAboutMissingPrototype(FD)) 4346 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4347 4348 if (FnBodyScope) 4349 PushDeclContext(FnBodyScope, FD); 4350 4351 // Check the validity of our function parameters 4352 CheckParmsForFunctionDef(FD); 4353 4354 // Introduce our parameters into the function scope 4355 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4356 ParmVarDecl *Param = FD->getParamDecl(p); 4357 Param->setOwningFunction(FD); 4358 4359 // If this has an identifier, add it to the scope stack. 4360 if (Param->getIdentifier() && FnBodyScope) 4361 PushOnScopeChains(Param, FnBodyScope); 4362 } 4363 4364 // Checking attributes of current function definition 4365 // dllimport attribute. 4366 if (FD->getAttr<DLLImportAttr>() && 4367 (!FD->getAttr<DLLExportAttr>())) { 4368 // dllimport attribute cannot be applied to definition. 4369 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4370 Diag(FD->getLocation(), 4371 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4372 << "dllimport"; 4373 FD->setInvalidDecl(); 4374 return DeclPtrTy::make(FD); 4375 } else { 4376 // If a symbol previously declared dllimport is later defined, the 4377 // attribute is ignored in subsequent references, and a warning is 4378 // emitted. 4379 Diag(FD->getLocation(), 4380 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4381 << FD->getNameAsCString() << "dllimport"; 4382 } 4383 } 4384 return DeclPtrTy::make(FD); 4385} 4386 4387Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4388 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4389} 4390 4391Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4392 bool IsInstantiation) { 4393 Decl *dcl = D.getAs<Decl>(); 4394 Stmt *Body = BodyArg.takeAs<Stmt>(); 4395 4396 AnalysisContext AC(dcl); 4397 FunctionDecl *FD = 0; 4398 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4399 if (FunTmpl) 4400 FD = FunTmpl->getTemplatedDecl(); 4401 else 4402 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4403 4404 if (FD) { 4405 FD->setBody(Body); 4406 if (FD->isMain()) 4407 // C and C++ allow for main to automagically return 0. 4408 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4409 FD->setHasImplicitReturnZero(true); 4410 else 4411 CheckFallThroughForFunctionDef(FD, Body, AC); 4412 4413 if (!FD->isInvalidDecl()) 4414 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4415 4416 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4417 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4418 4419 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4420 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4421 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4422 MD->setBody(Body); 4423 CheckFallThroughForFunctionDef(MD, Body, AC); 4424 MD->setEndLoc(Body->getLocEnd()); 4425 4426 if (!MD->isInvalidDecl()) 4427 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4428 } else { 4429 Body->Destroy(Context); 4430 return DeclPtrTy(); 4431 } 4432 if (!IsInstantiation) 4433 PopDeclContext(); 4434 4435 // Verify and clean out per-function state. 4436 4437 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4438 4439 // Check goto/label use. 4440 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4441 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4442 LabelStmt *L = I->second; 4443 4444 // Verify that we have no forward references left. If so, there was a goto 4445 // or address of a label taken, but no definition of it. Label fwd 4446 // definitions are indicated with a null substmt. 4447 if (L->getSubStmt() != 0) 4448 continue; 4449 4450 // Emit error. 4451 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4452 4453 // At this point, we have gotos that use the bogus label. Stitch it into 4454 // the function body so that they aren't leaked and that the AST is well 4455 // formed. 4456 if (Body == 0) { 4457 // The whole function wasn't parsed correctly, just delete this. 4458 L->Destroy(Context); 4459 continue; 4460 } 4461 4462 // Otherwise, the body is valid: we want to stitch the label decl into the 4463 // function somewhere so that it is properly owned and so that the goto 4464 // has a valid target. Do this by creating a new compound stmt with the 4465 // label in it. 4466 4467 // Give the label a sub-statement. 4468 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4469 4470 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4471 cast<CXXTryStmt>(Body)->getTryBlock() : 4472 cast<CompoundStmt>(Body); 4473 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4474 Elements.push_back(L); 4475 Compound->setStmts(Context, &Elements[0], Elements.size()); 4476 } 4477 FunctionLabelMap.clear(); 4478 4479 if (!Body) return D; 4480 4481 CheckUnreachable(AC); 4482 4483 // Verify that that gotos and switch cases don't jump into scopes illegally. 4484 if (CurFunctionNeedsScopeChecking) 4485 DiagnoseInvalidJumps(Body); 4486 4487 // C++ constructors that have function-try-blocks can't have return 4488 // statements in the handlers of that block. (C++ [except.handle]p14) 4489 // Verify this. 4490 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4491 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4492 4493 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4494 MarkBaseAndMemberDestructorsReferenced(Destructor); 4495 4496 // If any errors have occurred, clear out any temporaries that may have 4497 // been leftover. This ensures that these temporaries won't be picked up for 4498 // deletion in some later function. 4499 if (PP.getDiagnostics().hasErrorOccurred()) 4500 ExprTemporaries.clear(); 4501 4502 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4503 return D; 4504} 4505 4506/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4507/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4508NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4509 IdentifierInfo &II, Scope *S) { 4510 // Before we produce a declaration for an implicitly defined 4511 // function, see whether there was a locally-scoped declaration of 4512 // this name as a function or variable. If so, use that 4513 // (non-visible) declaration, and complain about it. 4514 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4515 = LocallyScopedExternalDecls.find(&II); 4516 if (Pos != LocallyScopedExternalDecls.end()) { 4517 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4518 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4519 return Pos->second; 4520 } 4521 4522 // Extension in C99. Legal in C90, but warn about it. 4523 if (II.getName().startswith("__builtin_")) 4524 Diag(Loc, diag::warn_builtin_unknown) << &II; 4525 else if (getLangOptions().C99) 4526 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4527 else 4528 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4529 4530 // Set a Declarator for the implicit definition: int foo(); 4531 const char *Dummy; 4532 DeclSpec DS; 4533 unsigned DiagID; 4534 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4535 Error = Error; // Silence warning. 4536 assert(!Error && "Error setting up implicit decl!"); 4537 Declarator D(DS, Declarator::BlockContext); 4538 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4539 0, 0, false, SourceLocation(), 4540 false, 0,0,0, Loc, Loc, D), 4541 SourceLocation()); 4542 D.SetIdentifier(&II, Loc); 4543 4544 // Insert this function into translation-unit scope. 4545 4546 DeclContext *PrevDC = CurContext; 4547 CurContext = Context.getTranslationUnitDecl(); 4548 4549 FunctionDecl *FD = 4550 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4551 FD->setImplicit(); 4552 4553 CurContext = PrevDC; 4554 4555 AddKnownFunctionAttributes(FD); 4556 4557 return FD; 4558} 4559 4560/// \brief Adds any function attributes that we know a priori based on 4561/// the declaration of this function. 4562/// 4563/// These attributes can apply both to implicitly-declared builtins 4564/// (like __builtin___printf_chk) or to library-declared functions 4565/// like NSLog or printf. 4566void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4567 if (FD->isInvalidDecl()) 4568 return; 4569 4570 // If this is a built-in function, map its builtin attributes to 4571 // actual attributes. 4572 if (unsigned BuiltinID = FD->getBuiltinID()) { 4573 // Handle printf-formatting attributes. 4574 unsigned FormatIdx; 4575 bool HasVAListArg; 4576 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4577 if (!FD->getAttr<FormatAttr>()) 4578 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4579 HasVAListArg ? 0 : FormatIdx + 2)); 4580 } 4581 4582 // Mark const if we don't care about errno and that is the only 4583 // thing preventing the function from being const. This allows 4584 // IRgen to use LLVM intrinsics for such functions. 4585 if (!getLangOptions().MathErrno && 4586 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4587 if (!FD->getAttr<ConstAttr>()) 4588 FD->addAttr(::new (Context) ConstAttr()); 4589 } 4590 4591 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4592 FD->addAttr(::new (Context) NoReturnAttr()); 4593 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4594 FD->addAttr(::new (Context) NoThrowAttr()); 4595 if (Context.BuiltinInfo.isConst(BuiltinID)) 4596 FD->addAttr(::new (Context) ConstAttr()); 4597 } 4598 4599 IdentifierInfo *Name = FD->getIdentifier(); 4600 if (!Name) 4601 return; 4602 if ((!getLangOptions().CPlusPlus && 4603 FD->getDeclContext()->isTranslationUnit()) || 4604 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4605 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4606 LinkageSpecDecl::lang_c)) { 4607 // Okay: this could be a libc/libm/Objective-C function we know 4608 // about. 4609 } else 4610 return; 4611 4612 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4613 // FIXME: NSLog and NSLogv should be target specific 4614 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4615 // FIXME: We known better than our headers. 4616 const_cast<FormatAttr *>(Format)->setType("printf"); 4617 } else 4618 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4619 Name->isStr("NSLogv") ? 0 : 2)); 4620 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4621 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4622 // target-specific builtins, perhaps? 4623 if (!FD->getAttr<FormatAttr>()) 4624 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4625 Name->isStr("vasprintf") ? 0 : 3)); 4626 } 4627} 4628 4629TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4630 TypeSourceInfo *TInfo) { 4631 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4632 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4633 4634 if (!TInfo) { 4635 assert(D.isInvalidType() && "no declarator info for valid type"); 4636 TInfo = Context.getTrivialTypeSourceInfo(T); 4637 } 4638 4639 // Scope manipulation handled by caller. 4640 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4641 D.getIdentifierLoc(), 4642 D.getIdentifier(), 4643 TInfo); 4644 4645 if (const TagType *TT = T->getAs<TagType>()) { 4646 TagDecl *TD = TT->getDecl(); 4647 4648 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4649 // keep track of the TypedefDecl. 4650 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4651 TD->setTypedefForAnonDecl(NewTD); 4652 } 4653 4654 if (D.isInvalidType()) 4655 NewTD->setInvalidDecl(); 4656 return NewTD; 4657} 4658 4659 4660/// \brief Determine whether a tag with a given kind is acceptable 4661/// as a redeclaration of the given tag declaration. 4662/// 4663/// \returns true if the new tag kind is acceptable, false otherwise. 4664bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4665 TagDecl::TagKind NewTag, 4666 SourceLocation NewTagLoc, 4667 const IdentifierInfo &Name) { 4668 // C++ [dcl.type.elab]p3: 4669 // The class-key or enum keyword present in the 4670 // elaborated-type-specifier shall agree in kind with the 4671 // declaration to which the name in theelaborated-type-specifier 4672 // refers. This rule also applies to the form of 4673 // elaborated-type-specifier that declares a class-name or 4674 // friend class since it can be construed as referring to the 4675 // definition of the class. Thus, in any 4676 // elaborated-type-specifier, the enum keyword shall be used to 4677 // refer to an enumeration (7.2), the union class-keyshall be 4678 // used to refer to a union (clause 9), and either the class or 4679 // struct class-key shall be used to refer to a class (clause 9) 4680 // declared using the class or struct class-key. 4681 TagDecl::TagKind OldTag = Previous->getTagKind(); 4682 if (OldTag == NewTag) 4683 return true; 4684 4685 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4686 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4687 // Warn about the struct/class tag mismatch. 4688 bool isTemplate = false; 4689 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4690 isTemplate = Record->getDescribedClassTemplate(); 4691 4692 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4693 << (NewTag == TagDecl::TK_class) 4694 << isTemplate << &Name 4695 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4696 OldTag == TagDecl::TK_class? "class" : "struct"); 4697 Diag(Previous->getLocation(), diag::note_previous_use); 4698 return true; 4699 } 4700 return false; 4701} 4702 4703/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4704/// former case, Name will be non-null. In the later case, Name will be null. 4705/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4706/// reference/declaration/definition of a tag. 4707Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4708 SourceLocation KWLoc, const CXXScopeSpec &SS, 4709 IdentifierInfo *Name, SourceLocation NameLoc, 4710 AttributeList *Attr, AccessSpecifier AS, 4711 MultiTemplateParamsArg TemplateParameterLists, 4712 bool &OwnedDecl, bool &IsDependent) { 4713 // If this is not a definition, it must have a name. 4714 assert((Name != 0 || TUK == TUK_Definition) && 4715 "Nameless record must be a definition!"); 4716 4717 OwnedDecl = false; 4718 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4719 4720 // FIXME: Check explicit specializations more carefully. 4721 bool isExplicitSpecialization = false; 4722 if (TUK != TUK_Reference) { 4723 if (TemplateParameterList *TemplateParams 4724 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4725 (TemplateParameterList**)TemplateParameterLists.get(), 4726 TemplateParameterLists.size(), 4727 isExplicitSpecialization)) { 4728 if (TemplateParams->size() > 0) { 4729 // This is a declaration or definition of a class template (which may 4730 // be a member of another template). 4731 OwnedDecl = false; 4732 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4733 SS, Name, NameLoc, Attr, 4734 TemplateParams, 4735 AS); 4736 TemplateParameterLists.release(); 4737 return Result.get(); 4738 } else { 4739 // The "template<>" header is extraneous. 4740 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4741 << ElaboratedType::getNameForTagKind(Kind) << Name; 4742 isExplicitSpecialization = true; 4743 } 4744 } 4745 4746 TemplateParameterLists.release(); 4747 } 4748 4749 DeclContext *SearchDC = CurContext; 4750 DeclContext *DC = CurContext; 4751 bool isStdBadAlloc = false; 4752 bool Invalid = false; 4753 4754 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4755 : NotForRedeclaration); 4756 4757 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4758 4759 if (Name && SS.isNotEmpty()) { 4760 // We have a nested-name tag ('struct foo::bar'). 4761 4762 // Check for invalid 'foo::'. 4763 if (SS.isInvalid()) { 4764 Name = 0; 4765 goto CreateNewDecl; 4766 } 4767 4768 // If this is a friend or a reference to a class in a dependent 4769 // context, don't try to make a decl for it. 4770 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4771 DC = computeDeclContext(SS, false); 4772 if (!DC) { 4773 IsDependent = true; 4774 return DeclPtrTy(); 4775 } 4776 } 4777 4778 if (RequireCompleteDeclContext(SS)) 4779 return DeclPtrTy::make((Decl *)0); 4780 4781 DC = computeDeclContext(SS, true); 4782 SearchDC = DC; 4783 // Look-up name inside 'foo::'. 4784 LookupQualifiedName(Previous, DC); 4785 4786 if (Previous.isAmbiguous()) 4787 return DeclPtrTy(); 4788 4789 if (Previous.empty()) { 4790 // Name lookup did not find anything. However, if the 4791 // nested-name-specifier refers to the current instantiation, 4792 // and that current instantiation has any dependent base 4793 // classes, we might find something at instantiation time: treat 4794 // this as a dependent elaborated-type-specifier. 4795 if (Previous.wasNotFoundInCurrentInstantiation()) { 4796 IsDependent = true; 4797 return DeclPtrTy(); 4798 } 4799 4800 // A tag 'foo::bar' must already exist. 4801 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4802 Name = 0; 4803 Invalid = true; 4804 goto CreateNewDecl; 4805 } 4806 } else if (Name) { 4807 // If this is a named struct, check to see if there was a previous forward 4808 // declaration or definition. 4809 // FIXME: We're looking into outer scopes here, even when we 4810 // shouldn't be. Doing so can result in ambiguities that we 4811 // shouldn't be diagnosing. 4812 LookupName(Previous, S); 4813 4814 // Note: there used to be some attempt at recovery here. 4815 if (Previous.isAmbiguous()) 4816 return DeclPtrTy(); 4817 4818 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4819 // FIXME: This makes sure that we ignore the contexts associated 4820 // with C structs, unions, and enums when looking for a matching 4821 // tag declaration or definition. See the similar lookup tweak 4822 // in Sema::LookupName; is there a better way to deal with this? 4823 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4824 SearchDC = SearchDC->getParent(); 4825 } 4826 } 4827 4828 if (Previous.isSingleResult() && 4829 Previous.getFoundDecl()->isTemplateParameter()) { 4830 // Maybe we will complain about the shadowed template parameter. 4831 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4832 // Just pretend that we didn't see the previous declaration. 4833 Previous.clear(); 4834 } 4835 4836 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4837 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4838 // This is a declaration of or a reference to "std::bad_alloc". 4839 isStdBadAlloc = true; 4840 4841 if (Previous.empty() && StdBadAlloc) { 4842 // std::bad_alloc has been implicitly declared (but made invisible to 4843 // name lookup). Fill in this implicit declaration as the previous 4844 // declaration, so that the declarations get chained appropriately. 4845 Previous.addDecl(StdBadAlloc); 4846 } 4847 } 4848 4849 if (!Previous.empty()) { 4850 assert(Previous.isSingleResult()); 4851 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4852 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4853 // If this is a use of a previous tag, or if the tag is already declared 4854 // in the same scope (so that the definition/declaration completes or 4855 // rementions the tag), reuse the decl. 4856 if (TUK == TUK_Reference || TUK == TUK_Friend || 4857 isDeclInScope(PrevDecl, SearchDC, S)) { 4858 // Make sure that this wasn't declared as an enum and now used as a 4859 // struct or something similar. 4860 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4861 bool SafeToContinue 4862 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4863 Kind != TagDecl::TK_enum); 4864 if (SafeToContinue) 4865 Diag(KWLoc, diag::err_use_with_wrong_tag) 4866 << Name 4867 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4868 PrevTagDecl->getKindName()); 4869 else 4870 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4871 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4872 4873 if (SafeToContinue) 4874 Kind = PrevTagDecl->getTagKind(); 4875 else { 4876 // Recover by making this an anonymous redefinition. 4877 Name = 0; 4878 Previous.clear(); 4879 Invalid = true; 4880 } 4881 } 4882 4883 if (!Invalid) { 4884 // If this is a use, just return the declaration we found. 4885 4886 // FIXME: In the future, return a variant or some other clue 4887 // for the consumer of this Decl to know it doesn't own it. 4888 // For our current ASTs this shouldn't be a problem, but will 4889 // need to be changed with DeclGroups. 4890 if (TUK == TUK_Reference || TUK == TUK_Friend) 4891 return DeclPtrTy::make(PrevTagDecl); 4892 4893 // Diagnose attempts to redefine a tag. 4894 if (TUK == TUK_Definition) { 4895 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4896 // If we're defining a specialization and the previous definition 4897 // is from an implicit instantiation, don't emit an error 4898 // here; we'll catch this in the general case below. 4899 if (!isExplicitSpecialization || 4900 !isa<CXXRecordDecl>(Def) || 4901 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4902 == TSK_ExplicitSpecialization) { 4903 Diag(NameLoc, diag::err_redefinition) << Name; 4904 Diag(Def->getLocation(), diag::note_previous_definition); 4905 // If this is a redefinition, recover by making this 4906 // struct be anonymous, which will make any later 4907 // references get the previous definition. 4908 Name = 0; 4909 Previous.clear(); 4910 Invalid = true; 4911 } 4912 } else { 4913 // If the type is currently being defined, complain 4914 // about a nested redefinition. 4915 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4916 if (Tag->isBeingDefined()) { 4917 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4918 Diag(PrevTagDecl->getLocation(), 4919 diag::note_previous_definition); 4920 Name = 0; 4921 Previous.clear(); 4922 Invalid = true; 4923 } 4924 } 4925 4926 // Okay, this is definition of a previously declared or referenced 4927 // tag PrevDecl. We're going to create a new Decl for it. 4928 } 4929 } 4930 // If we get here we have (another) forward declaration or we 4931 // have a definition. Just create a new decl. 4932 4933 } else { 4934 // If we get here, this is a definition of a new tag type in a nested 4935 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4936 // new decl/type. We set PrevDecl to NULL so that the entities 4937 // have distinct types. 4938 Previous.clear(); 4939 } 4940 // If we get here, we're going to create a new Decl. If PrevDecl 4941 // is non-NULL, it's a definition of the tag declared by 4942 // PrevDecl. If it's NULL, we have a new definition. 4943 } else { 4944 // PrevDecl is a namespace, template, or anything else 4945 // that lives in the IDNS_Tag identifier namespace. 4946 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4947 // The tag name clashes with a namespace name, issue an error and 4948 // recover by making this tag be anonymous. 4949 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4950 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4951 Name = 0; 4952 Previous.clear(); 4953 Invalid = true; 4954 } else { 4955 // The existing declaration isn't relevant to us; we're in a 4956 // new scope, so clear out the previous declaration. 4957 Previous.clear(); 4958 } 4959 } 4960 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4961 // C++ [basic.scope.pdecl]p5: 4962 // -- for an elaborated-type-specifier of the form 4963 // 4964 // class-key identifier 4965 // 4966 // if the elaborated-type-specifier is used in the 4967 // decl-specifier-seq or parameter-declaration-clause of a 4968 // function defined in namespace scope, the identifier is 4969 // declared as a class-name in the namespace that contains 4970 // the declaration; otherwise, except as a friend 4971 // declaration, the identifier is declared in the smallest 4972 // non-class, non-function-prototype scope that contains the 4973 // declaration. 4974 // 4975 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4976 // C structs and unions. 4977 // 4978 // It is an error in C++ to declare (rather than define) an enum 4979 // type, including via an elaborated type specifier. We'll 4980 // diagnose that later; for now, declare the enum in the same 4981 // scope as we would have picked for any other tag type. 4982 // 4983 // GNU C also supports this behavior as part of its incomplete 4984 // enum types extension, while GNU C++ does not. 4985 // 4986 // Find the context where we'll be declaring the tag. 4987 // FIXME: We would like to maintain the current DeclContext as the 4988 // lexical context, 4989 while (SearchDC->isRecord()) 4990 SearchDC = SearchDC->getParent(); 4991 4992 // Find the scope where we'll be declaring the tag. 4993 while (S->isClassScope() || 4994 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4995 ((S->getFlags() & Scope::DeclScope) == 0) || 4996 (S->getEntity() && 4997 ((DeclContext *)S->getEntity())->isTransparentContext())) 4998 S = S->getParent(); 4999 5000 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 5001 // C++ [namespace.memdef]p3: 5002 // If a friend declaration in a non-local class first declares a 5003 // class or function, the friend class or function is a member of 5004 // the innermost enclosing namespace. 5005 while (!SearchDC->isFileContext()) 5006 SearchDC = SearchDC->getParent(); 5007 5008 // The entity of a decl scope is a DeclContext; see PushDeclContext. 5009 while (S->getEntity() != SearchDC) 5010 S = S->getParent(); 5011 } 5012 5013CreateNewDecl: 5014 5015 TagDecl *PrevDecl = 0; 5016 if (Previous.isSingleResult()) 5017 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5018 5019 // If there is an identifier, use the location of the identifier as the 5020 // location of the decl, otherwise use the location of the struct/union 5021 // keyword. 5022 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5023 5024 // Otherwise, create a new declaration. If there is a previous 5025 // declaration of the same entity, the two will be linked via 5026 // PrevDecl. 5027 TagDecl *New; 5028 5029 if (Kind == TagDecl::TK_enum) { 5030 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5031 // enum X { A, B, C } D; D should chain to X. 5032 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5033 cast_or_null<EnumDecl>(PrevDecl)); 5034 // If this is an undefined enum, warn. 5035 if (TUK != TUK_Definition && !Invalid) { 5036 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5037 : diag::ext_forward_ref_enum; 5038 Diag(Loc, DK); 5039 } 5040 } else { 5041 // struct/union/class 5042 5043 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5044 // struct X { int A; } D; D should chain to X. 5045 if (getLangOptions().CPlusPlus) { 5046 // FIXME: Look for a way to use RecordDecl for simple structs. 5047 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5048 cast_or_null<CXXRecordDecl>(PrevDecl)); 5049 5050 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5051 StdBadAlloc = cast<CXXRecordDecl>(New); 5052 } else 5053 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5054 cast_or_null<RecordDecl>(PrevDecl)); 5055 } 5056 5057 if (Kind != TagDecl::TK_enum) { 5058 // Handle #pragma pack: if the #pragma pack stack has non-default 5059 // alignment, make up a packed attribute for this decl. These 5060 // attributes are checked when the ASTContext lays out the 5061 // structure. 5062 // 5063 // It is important for implementing the correct semantics that this 5064 // happen here (in act on tag decl). The #pragma pack stack is 5065 // maintained as a result of parser callbacks which can occur at 5066 // many points during the parsing of a struct declaration (because 5067 // the #pragma tokens are effectively skipped over during the 5068 // parsing of the struct). 5069 if (unsigned Alignment = getPragmaPackAlignment()) 5070 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5071 } 5072 5073 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5074 // C++ [dcl.typedef]p3: 5075 // [...] Similarly, in a given scope, a class or enumeration 5076 // shall not be declared with the same name as a typedef-name 5077 // that is declared in that scope and refers to a type other 5078 // than the class or enumeration itself. 5079 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5080 ForRedeclaration); 5081 LookupName(Lookup, S); 5082 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5083 NamedDecl *PrevTypedefNamed = PrevTypedef; 5084 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5085 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5086 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5087 Diag(Loc, diag::err_tag_definition_of_typedef) 5088 << Context.getTypeDeclType(New) 5089 << PrevTypedef->getUnderlyingType(); 5090 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5091 Invalid = true; 5092 } 5093 } 5094 5095 // If this is a specialization of a member class (of a class template), 5096 // check the specialization. 5097 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5098 Invalid = true; 5099 5100 if (Invalid) 5101 New->setInvalidDecl(); 5102 5103 if (Attr) 5104 ProcessDeclAttributeList(S, New, Attr); 5105 5106 // If we're declaring or defining a tag in function prototype scope 5107 // in C, note that this type can only be used within the function. 5108 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5109 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5110 5111 // Set the lexical context. If the tag has a C++ scope specifier, the 5112 // lexical context will be different from the semantic context. 5113 New->setLexicalDeclContext(CurContext); 5114 5115 // Mark this as a friend decl if applicable. 5116 if (TUK == TUK_Friend) 5117 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5118 5119 // Set the access specifier. 5120 if (!Invalid && TUK != TUK_Friend) 5121 SetMemberAccessSpecifier(New, PrevDecl, AS); 5122 5123 if (TUK == TUK_Definition) 5124 New->startDefinition(); 5125 5126 // If this has an identifier, add it to the scope stack. 5127 if (TUK == TUK_Friend) { 5128 // We might be replacing an existing declaration in the lookup tables; 5129 // if so, borrow its access specifier. 5130 if (PrevDecl) 5131 New->setAccess(PrevDecl->getAccess()); 5132 5133 // Friend tag decls are visible in fairly strange ways. 5134 if (!CurContext->isDependentContext()) { 5135 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5136 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5137 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5138 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5139 } 5140 } else if (Name) { 5141 S = getNonFieldDeclScope(S); 5142 PushOnScopeChains(New, S); 5143 } else { 5144 CurContext->addDecl(New); 5145 } 5146 5147 // If this is the C FILE type, notify the AST context. 5148 if (IdentifierInfo *II = New->getIdentifier()) 5149 if (!New->isInvalidDecl() && 5150 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5151 II->isStr("FILE")) 5152 Context.setFILEDecl(New); 5153 5154 OwnedDecl = true; 5155 return DeclPtrTy::make(New); 5156} 5157 5158void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5159 AdjustDeclIfTemplate(TagD); 5160 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5161 5162 // Enter the tag context. 5163 PushDeclContext(S, Tag); 5164} 5165 5166void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5167 SourceLocation LBraceLoc) { 5168 AdjustDeclIfTemplate(TagD); 5169 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5170 5171 FieldCollector->StartClass(); 5172 5173 if (!Record->getIdentifier()) 5174 return; 5175 5176 // C++ [class]p2: 5177 // [...] The class-name is also inserted into the scope of the 5178 // class itself; this is known as the injected-class-name. For 5179 // purposes of access checking, the injected-class-name is treated 5180 // as if it were a public member name. 5181 CXXRecordDecl *InjectedClassName 5182 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5183 CurContext, Record->getLocation(), 5184 Record->getIdentifier(), 5185 Record->getTagKeywordLoc(), 5186 Record); 5187 InjectedClassName->setImplicit(); 5188 InjectedClassName->setAccess(AS_public); 5189 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5190 InjectedClassName->setDescribedClassTemplate(Template); 5191 PushOnScopeChains(InjectedClassName, S); 5192 assert(InjectedClassName->isInjectedClassName() && 5193 "Broken injected-class-name"); 5194} 5195 5196// Traverses the class and any nested classes, making a note of any 5197// dynamic classes that have no key function so that we can mark all of 5198// their virtual member functions as "used" at the end of the translation 5199// unit. This ensures that all functions needed by the vtable will get 5200// instantiated/synthesized. 5201static void 5202RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5203 SourceLocation Loc) { 5204 // We don't look at dependent or undefined classes. 5205 if (Record->isDependentContext() || !Record->isDefinition()) 5206 return; 5207 5208 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 5209 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 5210 5211 for (DeclContext::decl_iterator D = Record->decls_begin(), 5212 DEnd = Record->decls_end(); 5213 D != DEnd; ++D) { 5214 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5215 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5216 } 5217} 5218 5219void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5220 SourceLocation RBraceLoc) { 5221 AdjustDeclIfTemplate(TagD); 5222 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5223 Tag->setRBraceLoc(RBraceLoc); 5224 5225 if (isa<CXXRecordDecl>(Tag)) 5226 FieldCollector->FinishClass(); 5227 5228 // Exit this scope of this tag's definition. 5229 PopDeclContext(); 5230 5231 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 5232 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5233 RBraceLoc); 5234 5235 // Notify the consumer that we've defined a tag. 5236 Consumer.HandleTagDeclDefinition(Tag); 5237} 5238 5239// Note that FieldName may be null for anonymous bitfields. 5240bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5241 QualType FieldTy, const Expr *BitWidth, 5242 bool *ZeroWidth) { 5243 // Default to true; that shouldn't confuse checks for emptiness 5244 if (ZeroWidth) 5245 *ZeroWidth = true; 5246 5247 // C99 6.7.2.1p4 - verify the field type. 5248 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5249 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5250 // Handle incomplete types with specific error. 5251 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5252 return true; 5253 if (FieldName) 5254 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5255 << FieldName << FieldTy << BitWidth->getSourceRange(); 5256 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5257 << FieldTy << BitWidth->getSourceRange(); 5258 } 5259 5260 // If the bit-width is type- or value-dependent, don't try to check 5261 // it now. 5262 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5263 return false; 5264 5265 llvm::APSInt Value; 5266 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5267 return true; 5268 5269 if (Value != 0 && ZeroWidth) 5270 *ZeroWidth = false; 5271 5272 // Zero-width bitfield is ok for anonymous field. 5273 if (Value == 0 && FieldName) 5274 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5275 5276 if (Value.isSigned() && Value.isNegative()) { 5277 if (FieldName) 5278 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5279 << FieldName << Value.toString(10); 5280 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5281 << Value.toString(10); 5282 } 5283 5284 if (!FieldTy->isDependentType()) { 5285 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5286 if (Value.getZExtValue() > TypeSize) { 5287 if (FieldName) 5288 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5289 << FieldName << (unsigned)TypeSize; 5290 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5291 << (unsigned)TypeSize; 5292 } 5293 } 5294 5295 return false; 5296} 5297 5298/// ActOnField - Each field of a struct/union/class is passed into this in order 5299/// to create a FieldDecl object for it. 5300Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5301 SourceLocation DeclStart, 5302 Declarator &D, ExprTy *BitfieldWidth) { 5303 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5304 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5305 AS_public); 5306 return DeclPtrTy::make(Res); 5307} 5308 5309/// HandleField - Analyze a field of a C struct or a C++ data member. 5310/// 5311FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5312 SourceLocation DeclStart, 5313 Declarator &D, Expr *BitWidth, 5314 AccessSpecifier AS) { 5315 IdentifierInfo *II = D.getIdentifier(); 5316 SourceLocation Loc = DeclStart; 5317 if (II) Loc = D.getIdentifierLoc(); 5318 5319 TypeSourceInfo *TInfo = 0; 5320 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5321 if (getLangOptions().CPlusPlus) 5322 CheckExtraCXXDefaultArguments(D); 5323 5324 DiagnoseFunctionSpecifiers(D); 5325 5326 if (D.getDeclSpec().isThreadSpecified()) 5327 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5328 5329 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5330 ForRedeclaration); 5331 5332 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5333 // Maybe we will complain about the shadowed template parameter. 5334 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5335 // Just pretend that we didn't see the previous declaration. 5336 PrevDecl = 0; 5337 } 5338 5339 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5340 PrevDecl = 0; 5341 5342 bool Mutable 5343 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5344 SourceLocation TSSL = D.getSourceRange().getBegin(); 5345 FieldDecl *NewFD 5346 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5347 AS, PrevDecl, &D); 5348 if (NewFD->isInvalidDecl() && PrevDecl) { 5349 // Don't introduce NewFD into scope; there's already something 5350 // with the same name in the same scope. 5351 } else if (II) { 5352 PushOnScopeChains(NewFD, S); 5353 } else 5354 Record->addDecl(NewFD); 5355 5356 return NewFD; 5357} 5358 5359/// \brief Build a new FieldDecl and check its well-formedness. 5360/// 5361/// This routine builds a new FieldDecl given the fields name, type, 5362/// record, etc. \p PrevDecl should refer to any previous declaration 5363/// with the same name and in the same scope as the field to be 5364/// created. 5365/// 5366/// \returns a new FieldDecl. 5367/// 5368/// \todo The Declarator argument is a hack. It will be removed once 5369FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5370 TypeSourceInfo *TInfo, 5371 RecordDecl *Record, SourceLocation Loc, 5372 bool Mutable, Expr *BitWidth, 5373 SourceLocation TSSL, 5374 AccessSpecifier AS, NamedDecl *PrevDecl, 5375 Declarator *D) { 5376 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5377 bool InvalidDecl = false; 5378 if (D) InvalidDecl = D->isInvalidType(); 5379 5380 // If we receive a broken type, recover by assuming 'int' and 5381 // marking this declaration as invalid. 5382 if (T.isNull()) { 5383 InvalidDecl = true; 5384 T = Context.IntTy; 5385 } 5386 5387 QualType EltTy = Context.getBaseElementType(T); 5388 if (!EltTy->isDependentType() && 5389 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5390 InvalidDecl = true; 5391 5392 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5393 // than a variably modified type. 5394 if (!InvalidDecl && T->isVariablyModifiedType()) { 5395 bool SizeIsNegative; 5396 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5397 SizeIsNegative); 5398 if (!FixedTy.isNull()) { 5399 Diag(Loc, diag::warn_illegal_constant_array_size); 5400 T = FixedTy; 5401 } else { 5402 if (SizeIsNegative) 5403 Diag(Loc, diag::err_typecheck_negative_array_size); 5404 else 5405 Diag(Loc, diag::err_typecheck_field_variable_size); 5406 InvalidDecl = true; 5407 } 5408 } 5409 5410 // Fields can not have abstract class types 5411 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5412 diag::err_abstract_type_in_decl, 5413 AbstractFieldType)) 5414 InvalidDecl = true; 5415 5416 bool ZeroWidth = false; 5417 // If this is declared as a bit-field, check the bit-field. 5418 if (!InvalidDecl && BitWidth && 5419 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5420 InvalidDecl = true; 5421 DeleteExpr(BitWidth); 5422 BitWidth = 0; 5423 ZeroWidth = false; 5424 } 5425 5426 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5427 BitWidth, Mutable); 5428 if (InvalidDecl) 5429 NewFD->setInvalidDecl(); 5430 5431 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5432 Diag(Loc, diag::err_duplicate_member) << II; 5433 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5434 NewFD->setInvalidDecl(); 5435 } 5436 5437 if (getLangOptions().CPlusPlus) { 5438 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5439 5440 if (!T->isPODType()) 5441 CXXRecord->setPOD(false); 5442 if (!ZeroWidth) 5443 CXXRecord->setEmpty(false); 5444 5445 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5446 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5447 5448 if (!RDecl->hasTrivialConstructor()) 5449 CXXRecord->setHasTrivialConstructor(false); 5450 if (!RDecl->hasTrivialCopyConstructor()) 5451 CXXRecord->setHasTrivialCopyConstructor(false); 5452 if (!RDecl->hasTrivialCopyAssignment()) 5453 CXXRecord->setHasTrivialCopyAssignment(false); 5454 if (!RDecl->hasTrivialDestructor()) 5455 CXXRecord->setHasTrivialDestructor(false); 5456 5457 // C++ 9.5p1: An object of a class with a non-trivial 5458 // constructor, a non-trivial copy constructor, a non-trivial 5459 // destructor, or a non-trivial copy assignment operator 5460 // cannot be a member of a union, nor can an array of such 5461 // objects. 5462 // TODO: C++0x alters this restriction significantly. 5463 if (Record->isUnion()) { 5464 // We check for copy constructors before constructors 5465 // because otherwise we'll never get complaints about 5466 // copy constructors. 5467 5468 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5469 5470 CXXSpecialMember member; 5471 if (!RDecl->hasTrivialCopyConstructor()) 5472 member = CXXCopyConstructor; 5473 else if (!RDecl->hasTrivialConstructor()) 5474 member = CXXDefaultConstructor; 5475 else if (!RDecl->hasTrivialCopyAssignment()) 5476 member = CXXCopyAssignment; 5477 else if (!RDecl->hasTrivialDestructor()) 5478 member = CXXDestructor; 5479 else 5480 member = invalid; 5481 5482 if (member != invalid) { 5483 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5484 DiagnoseNontrivial(RT, member); 5485 NewFD->setInvalidDecl(); 5486 } 5487 } 5488 } 5489 } 5490 5491 // FIXME: We need to pass in the attributes given an AST 5492 // representation, not a parser representation. 5493 if (D) 5494 // FIXME: What to pass instead of TUScope? 5495 ProcessDeclAttributes(TUScope, NewFD, *D); 5496 5497 if (T.isObjCGCWeak()) 5498 Diag(Loc, diag::warn_attribute_weak_on_field); 5499 5500 NewFD->setAccess(AS); 5501 5502 // C++ [dcl.init.aggr]p1: 5503 // An aggregate is an array or a class (clause 9) with [...] no 5504 // private or protected non-static data members (clause 11). 5505 // A POD must be an aggregate. 5506 if (getLangOptions().CPlusPlus && 5507 (AS == AS_private || AS == AS_protected)) { 5508 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5509 CXXRecord->setAggregate(false); 5510 CXXRecord->setPOD(false); 5511 } 5512 5513 return NewFD; 5514} 5515 5516/// DiagnoseNontrivial - Given that a class has a non-trivial 5517/// special member, figure out why. 5518void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5519 QualType QT(T, 0U); 5520 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5521 5522 // Check whether the member was user-declared. 5523 switch (member) { 5524 case CXXDefaultConstructor: 5525 if (RD->hasUserDeclaredConstructor()) { 5526 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5527 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5528 const FunctionDecl *body = 0; 5529 ci->getBody(body); 5530 if (!body || 5531 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5532 SourceLocation CtorLoc = ci->getLocation(); 5533 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5534 return; 5535 } 5536 } 5537 5538 assert(0 && "found no user-declared constructors"); 5539 return; 5540 } 5541 break; 5542 5543 case CXXCopyConstructor: 5544 if (RD->hasUserDeclaredCopyConstructor()) { 5545 SourceLocation CtorLoc = 5546 RD->getCopyConstructor(Context, 0)->getLocation(); 5547 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5548 return; 5549 } 5550 break; 5551 5552 case CXXCopyAssignment: 5553 if (RD->hasUserDeclaredCopyAssignment()) { 5554 // FIXME: this should use the location of the copy 5555 // assignment, not the type. 5556 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5557 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5558 return; 5559 } 5560 break; 5561 5562 case CXXDestructor: 5563 if (RD->hasUserDeclaredDestructor()) { 5564 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5565 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5566 return; 5567 } 5568 break; 5569 } 5570 5571 typedef CXXRecordDecl::base_class_iterator base_iter; 5572 5573 // Virtual bases and members inhibit trivial copying/construction, 5574 // but not trivial destruction. 5575 if (member != CXXDestructor) { 5576 // Check for virtual bases. vbases includes indirect virtual bases, 5577 // so we just iterate through the direct bases. 5578 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5579 if (bi->isVirtual()) { 5580 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5581 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5582 return; 5583 } 5584 5585 // Check for virtual methods. 5586 typedef CXXRecordDecl::method_iterator meth_iter; 5587 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5588 ++mi) { 5589 if (mi->isVirtual()) { 5590 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5591 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5592 return; 5593 } 5594 } 5595 } 5596 5597 bool (CXXRecordDecl::*hasTrivial)() const; 5598 switch (member) { 5599 case CXXDefaultConstructor: 5600 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5601 case CXXCopyConstructor: 5602 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5603 case CXXCopyAssignment: 5604 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5605 case CXXDestructor: 5606 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5607 default: 5608 assert(0 && "unexpected special member"); return; 5609 } 5610 5611 // Check for nontrivial bases (and recurse). 5612 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5613 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5614 assert(BaseRT && "Don't know how to handle dependent bases"); 5615 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5616 if (!(BaseRecTy->*hasTrivial)()) { 5617 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5618 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5619 DiagnoseNontrivial(BaseRT, member); 5620 return; 5621 } 5622 } 5623 5624 // Check for nontrivial members (and recurse). 5625 typedef RecordDecl::field_iterator field_iter; 5626 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5627 ++fi) { 5628 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5629 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5630 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5631 5632 if (!(EltRD->*hasTrivial)()) { 5633 SourceLocation FLoc = (*fi)->getLocation(); 5634 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5635 DiagnoseNontrivial(EltRT, member); 5636 return; 5637 } 5638 } 5639 } 5640 5641 assert(0 && "found no explanation for non-trivial member"); 5642} 5643 5644/// TranslateIvarVisibility - Translate visibility from a token ID to an 5645/// AST enum value. 5646static ObjCIvarDecl::AccessControl 5647TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5648 switch (ivarVisibility) { 5649 default: assert(0 && "Unknown visitibility kind"); 5650 case tok::objc_private: return ObjCIvarDecl::Private; 5651 case tok::objc_public: return ObjCIvarDecl::Public; 5652 case tok::objc_protected: return ObjCIvarDecl::Protected; 5653 case tok::objc_package: return ObjCIvarDecl::Package; 5654 } 5655} 5656 5657/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5658/// in order to create an IvarDecl object for it. 5659Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5660 SourceLocation DeclStart, 5661 DeclPtrTy IntfDecl, 5662 Declarator &D, ExprTy *BitfieldWidth, 5663 tok::ObjCKeywordKind Visibility) { 5664 5665 IdentifierInfo *II = D.getIdentifier(); 5666 Expr *BitWidth = (Expr*)BitfieldWidth; 5667 SourceLocation Loc = DeclStart; 5668 if (II) Loc = D.getIdentifierLoc(); 5669 5670 // FIXME: Unnamed fields can be handled in various different ways, for 5671 // example, unnamed unions inject all members into the struct namespace! 5672 5673 TypeSourceInfo *TInfo = 0; 5674 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5675 5676 if (BitWidth) { 5677 // 6.7.2.1p3, 6.7.2.1p4 5678 if (VerifyBitField(Loc, II, T, BitWidth)) { 5679 D.setInvalidType(); 5680 DeleteExpr(BitWidth); 5681 BitWidth = 0; 5682 } 5683 } else { 5684 // Not a bitfield. 5685 5686 // validate II. 5687 5688 } 5689 5690 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5691 // than a variably modified type. 5692 if (T->isVariablyModifiedType()) { 5693 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5694 D.setInvalidType(); 5695 } 5696 5697 // Get the visibility (access control) for this ivar. 5698 ObjCIvarDecl::AccessControl ac = 5699 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5700 : ObjCIvarDecl::None; 5701 // Must set ivar's DeclContext to its enclosing interface. 5702 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5703 DeclContext *EnclosingContext; 5704 if (ObjCImplementationDecl *IMPDecl = 5705 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5706 // Case of ivar declared in an implementation. Context is that of its class. 5707 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5708 assert(IDecl && "No class- ActOnIvar"); 5709 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5710 } else 5711 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5712 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5713 5714 // Construct the decl. 5715 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5716 EnclosingContext, Loc, II, T, 5717 TInfo, ac, (Expr *)BitfieldWidth); 5718 5719 if (II) { 5720 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5721 ForRedeclaration); 5722 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5723 && !isa<TagDecl>(PrevDecl)) { 5724 Diag(Loc, diag::err_duplicate_member) << II; 5725 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5726 NewID->setInvalidDecl(); 5727 } 5728 } 5729 5730 // Process attributes attached to the ivar. 5731 ProcessDeclAttributes(S, NewID, D); 5732 5733 if (D.isInvalidType()) 5734 NewID->setInvalidDecl(); 5735 5736 if (II) { 5737 // FIXME: When interfaces are DeclContexts, we'll need to add 5738 // these to the interface. 5739 S->AddDecl(DeclPtrTy::make(NewID)); 5740 IdResolver.AddDecl(NewID); 5741 } 5742 5743 return DeclPtrTy::make(NewID); 5744} 5745 5746void Sema::ActOnFields(Scope* S, 5747 SourceLocation RecLoc, DeclPtrTy RecDecl, 5748 DeclPtrTy *Fields, unsigned NumFields, 5749 SourceLocation LBrac, SourceLocation RBrac, 5750 AttributeList *Attr) { 5751 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5752 assert(EnclosingDecl && "missing record or interface decl"); 5753 5754 // If the decl this is being inserted into is invalid, then it may be a 5755 // redeclaration or some other bogus case. Don't try to add fields to it. 5756 if (EnclosingDecl->isInvalidDecl()) { 5757 // FIXME: Deallocate fields? 5758 return; 5759 } 5760 5761 5762 // Verify that all the fields are okay. 5763 unsigned NumNamedMembers = 0; 5764 llvm::SmallVector<FieldDecl*, 32> RecFields; 5765 5766 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5767 for (unsigned i = 0; i != NumFields; ++i) { 5768 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5769 5770 // Get the type for the field. 5771 Type *FDTy = FD->getType().getTypePtr(); 5772 5773 if (!FD->isAnonymousStructOrUnion()) { 5774 // Remember all fields written by the user. 5775 RecFields.push_back(FD); 5776 } 5777 5778 // If the field is already invalid for some reason, don't emit more 5779 // diagnostics about it. 5780 if (FD->isInvalidDecl()) { 5781 EnclosingDecl->setInvalidDecl(); 5782 continue; 5783 } 5784 5785 // C99 6.7.2.1p2: 5786 // A structure or union shall not contain a member with 5787 // incomplete or function type (hence, a structure shall not 5788 // contain an instance of itself, but may contain a pointer to 5789 // an instance of itself), except that the last member of a 5790 // structure with more than one named member may have incomplete 5791 // array type; such a structure (and any union containing, 5792 // possibly recursively, a member that is such a structure) 5793 // shall not be a member of a structure or an element of an 5794 // array. 5795 if (FDTy->isFunctionType()) { 5796 // Field declared as a function. 5797 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5798 << FD->getDeclName(); 5799 FD->setInvalidDecl(); 5800 EnclosingDecl->setInvalidDecl(); 5801 continue; 5802 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5803 Record && Record->isStruct()) { 5804 // Flexible array member. 5805 if (NumNamedMembers < 1) { 5806 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5807 << FD->getDeclName(); 5808 FD->setInvalidDecl(); 5809 EnclosingDecl->setInvalidDecl(); 5810 continue; 5811 } 5812 // Okay, we have a legal flexible array member at the end of the struct. 5813 if (Record) 5814 Record->setHasFlexibleArrayMember(true); 5815 } else if (!FDTy->isDependentType() && 5816 RequireCompleteType(FD->getLocation(), FD->getType(), 5817 diag::err_field_incomplete)) { 5818 // Incomplete type 5819 FD->setInvalidDecl(); 5820 EnclosingDecl->setInvalidDecl(); 5821 continue; 5822 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5823 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5824 // If this is a member of a union, then entire union becomes "flexible". 5825 if (Record && Record->isUnion()) { 5826 Record->setHasFlexibleArrayMember(true); 5827 } else { 5828 // If this is a struct/class and this is not the last element, reject 5829 // it. Note that GCC supports variable sized arrays in the middle of 5830 // structures. 5831 if (i != NumFields-1) 5832 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5833 << FD->getDeclName() << FD->getType(); 5834 else { 5835 // We support flexible arrays at the end of structs in 5836 // other structs as an extension. 5837 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5838 << FD->getDeclName(); 5839 if (Record) 5840 Record->setHasFlexibleArrayMember(true); 5841 } 5842 } 5843 } 5844 if (Record && FDTTy->getDecl()->hasObjectMember()) 5845 Record->setHasObjectMember(true); 5846 } else if (FDTy->isObjCInterfaceType()) { 5847 /// A field cannot be an Objective-c object 5848 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5849 FD->setInvalidDecl(); 5850 EnclosingDecl->setInvalidDecl(); 5851 continue; 5852 } else if (getLangOptions().ObjC1 && 5853 getLangOptions().getGCMode() != LangOptions::NonGC && 5854 Record && 5855 (FD->getType()->isObjCObjectPointerType() || 5856 FD->getType().isObjCGCStrong())) 5857 Record->setHasObjectMember(true); 5858 // Keep track of the number of named members. 5859 if (FD->getIdentifier()) 5860 ++NumNamedMembers; 5861 } 5862 5863 // Okay, we successfully defined 'Record'. 5864 if (Record) { 5865 Record->completeDefinition(Context); 5866 } else { 5867 ObjCIvarDecl **ClsFields = 5868 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5869 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5870 ID->setIVarList(ClsFields, RecFields.size(), Context); 5871 ID->setLocEnd(RBrac); 5872 // Add ivar's to class's DeclContext. 5873 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5874 ClsFields[i]->setLexicalDeclContext(ID); 5875 ID->addDecl(ClsFields[i]); 5876 } 5877 // Must enforce the rule that ivars in the base classes may not be 5878 // duplicates. 5879 if (ID->getSuperClass()) { 5880 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5881 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5882 ObjCIvarDecl* Ivar = (*IVI); 5883 5884 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5885 ObjCIvarDecl* prevIvar = 5886 ID->getSuperClass()->lookupInstanceVariable(II); 5887 if (prevIvar) { 5888 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5889 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5890 } 5891 } 5892 } 5893 } 5894 } else if (ObjCImplementationDecl *IMPDecl = 5895 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5896 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5897 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5898 // Ivar declared in @implementation never belongs to the implementation. 5899 // Only it is in implementation's lexical context. 5900 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5901 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5902 } 5903 } 5904 5905 if (Attr) 5906 ProcessDeclAttributeList(S, Record, Attr); 5907} 5908 5909EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5910 EnumConstantDecl *LastEnumConst, 5911 SourceLocation IdLoc, 5912 IdentifierInfo *Id, 5913 ExprArg val) { 5914 Expr *Val = (Expr *)val.get(); 5915 5916 llvm::APSInt EnumVal(32); 5917 QualType EltTy; 5918 if (Val) { 5919 if (Enum->isDependentType()) 5920 EltTy = Context.DependentTy; 5921 else { 5922 // Make sure to promote the operand type to int. 5923 UsualUnaryConversions(Val); 5924 if (Val != val.get()) { 5925 val.release(); 5926 val = Val; 5927 } 5928 5929 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5930 SourceLocation ExpLoc; 5931 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5932 Val = 0; 5933 } else { 5934 EltTy = Val->getType(); 5935 } 5936 } 5937 } 5938 5939 if (!Val) { 5940 if (Enum->isDependentType()) 5941 EltTy = Context.DependentTy; 5942 else if (LastEnumConst) { 5943 // Assign the last value + 1. 5944 EnumVal = LastEnumConst->getInitVal(); 5945 ++EnumVal; 5946 5947 // Check for overflow on increment. 5948 if (EnumVal < LastEnumConst->getInitVal()) 5949 Diag(IdLoc, diag::warn_enum_value_overflow); 5950 5951 EltTy = LastEnumConst->getType(); 5952 } else { 5953 // First value, set to zero. 5954 EltTy = Context.IntTy; 5955 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5956 EnumVal.setIsSigned(true); 5957 } 5958 } 5959 5960 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5961 5962 val.release(); 5963 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5964 Val, EnumVal); 5965} 5966 5967 5968Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5969 DeclPtrTy lastEnumConst, 5970 SourceLocation IdLoc, 5971 IdentifierInfo *Id, 5972 SourceLocation EqualLoc, ExprTy *val) { 5973 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5974 EnumConstantDecl *LastEnumConst = 5975 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5976 Expr *Val = static_cast<Expr*>(val); 5977 5978 // The scope passed in may not be a decl scope. Zip up the scope tree until 5979 // we find one that is. 5980 S = getNonFieldDeclScope(S); 5981 5982 // Verify that there isn't already something declared with this name in this 5983 // scope. 5984 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5985 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5986 // Maybe we will complain about the shadowed template parameter. 5987 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5988 // Just pretend that we didn't see the previous declaration. 5989 PrevDecl = 0; 5990 } 5991 5992 if (PrevDecl) { 5993 // When in C++, we may get a TagDecl with the same name; in this case the 5994 // enum constant will 'hide' the tag. 5995 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5996 "Received TagDecl when not in C++!"); 5997 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5998 if (isa<EnumConstantDecl>(PrevDecl)) 5999 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6000 else 6001 Diag(IdLoc, diag::err_redefinition) << Id; 6002 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6003 if (Val) Val->Destroy(Context); 6004 return DeclPtrTy(); 6005 } 6006 } 6007 6008 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6009 IdLoc, Id, Owned(Val)); 6010 6011 // Register this decl in the current scope stack. 6012 if (New) 6013 PushOnScopeChains(New, S); 6014 6015 return DeclPtrTy::make(New); 6016} 6017 6018void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6019 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6020 DeclPtrTy *Elements, unsigned NumElements, 6021 Scope *S, AttributeList *Attr) { 6022 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6023 QualType EnumType = Context.getTypeDeclType(Enum); 6024 6025 if (Attr) 6026 ProcessDeclAttributeList(S, Enum, Attr); 6027 6028 if (Enum->isDependentType()) { 6029 for (unsigned i = 0; i != NumElements; ++i) { 6030 EnumConstantDecl *ECD = 6031 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6032 if (!ECD) continue; 6033 6034 ECD->setType(EnumType); 6035 } 6036 6037 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 6038 return; 6039 } 6040 6041 // TODO: If the result value doesn't fit in an int, it must be a long or long 6042 // long value. ISO C does not support this, but GCC does as an extension, 6043 // emit a warning. 6044 unsigned IntWidth = Context.Target.getIntWidth(); 6045 unsigned CharWidth = Context.Target.getCharWidth(); 6046 unsigned ShortWidth = Context.Target.getShortWidth(); 6047 6048 // Verify that all the values are okay, compute the size of the values, and 6049 // reverse the list. 6050 unsigned NumNegativeBits = 0; 6051 unsigned NumPositiveBits = 0; 6052 6053 // Keep track of whether all elements have type int. 6054 bool AllElementsInt = true; 6055 6056 for (unsigned i = 0; i != NumElements; ++i) { 6057 EnumConstantDecl *ECD = 6058 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6059 if (!ECD) continue; // Already issued a diagnostic. 6060 6061 // If the enum value doesn't fit in an int, emit an extension warning. 6062 const llvm::APSInt &InitVal = ECD->getInitVal(); 6063 assert(InitVal.getBitWidth() >= IntWidth && 6064 "Should have promoted value to int"); 6065 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 6066 llvm::APSInt V(InitVal); 6067 V.trunc(IntWidth); 6068 V.extend(InitVal.getBitWidth()); 6069 if (V != InitVal) 6070 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 6071 << InitVal.toString(10); 6072 } 6073 6074 // Keep track of the size of positive and negative values. 6075 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6076 NumPositiveBits = std::max(NumPositiveBits, 6077 (unsigned)InitVal.getActiveBits()); 6078 else 6079 NumNegativeBits = std::max(NumNegativeBits, 6080 (unsigned)InitVal.getMinSignedBits()); 6081 6082 // Keep track of whether every enum element has type int (very commmon). 6083 if (AllElementsInt) 6084 AllElementsInt = ECD->getType() == Context.IntTy; 6085 } 6086 6087 // Figure out the type that should be used for this enum. 6088 // FIXME: Support -fshort-enums. 6089 QualType BestType; 6090 unsigned BestWidth; 6091 6092 // C++0x N3000 [conv.prom]p3: 6093 // An rvalue of an unscoped enumeration type whose underlying 6094 // type is not fixed can be converted to an rvalue of the first 6095 // of the following types that can represent all the values of 6096 // the enumeration: int, unsigned int, long int, unsigned long 6097 // int, long long int, or unsigned long long int. 6098 // C99 6.4.4.3p2: 6099 // An identifier declared as an enumeration constant has type int. 6100 // The C99 rule is modified by a gcc extension 6101 QualType BestPromotionType; 6102 6103 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6104 6105 if (NumNegativeBits) { 6106 // If there is a negative value, figure out the smallest integer type (of 6107 // int/long/longlong) that fits. 6108 // If it's packed, check also if it fits a char or a short. 6109 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6110 BestType = Context.SignedCharTy; 6111 BestWidth = CharWidth; 6112 } else if (Packed && NumNegativeBits <= ShortWidth && 6113 NumPositiveBits < ShortWidth) { 6114 BestType = Context.ShortTy; 6115 BestWidth = ShortWidth; 6116 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6117 BestType = Context.IntTy; 6118 BestWidth = IntWidth; 6119 } else { 6120 BestWidth = Context.Target.getLongWidth(); 6121 6122 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6123 BestType = Context.LongTy; 6124 } else { 6125 BestWidth = Context.Target.getLongLongWidth(); 6126 6127 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6128 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6129 BestType = Context.LongLongTy; 6130 } 6131 } 6132 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6133 } else { 6134 // If there is no negative value, figure out which of uint, ulong, ulonglong 6135 // fits. 6136 // If it's packed, check also if it fits a char or a short. 6137 if (Packed && NumPositiveBits <= CharWidth) { 6138 BestType = Context.UnsignedCharTy; 6139 BestPromotionType = Context.IntTy; 6140 BestWidth = CharWidth; 6141 } else if (Packed && NumPositiveBits <= ShortWidth) { 6142 BestType = Context.UnsignedShortTy; 6143 BestPromotionType = Context.IntTy; 6144 BestWidth = ShortWidth; 6145 } else if (NumPositiveBits <= IntWidth) { 6146 BestType = Context.UnsignedIntTy; 6147 BestWidth = IntWidth; 6148 BestPromotionType = (NumPositiveBits == BestWidth 6149 ? Context.UnsignedIntTy : Context.IntTy); 6150 } else if (NumPositiveBits <= 6151 (BestWidth = Context.Target.getLongWidth())) { 6152 BestType = Context.UnsignedLongTy; 6153 BestPromotionType = (NumPositiveBits == BestWidth 6154 ? Context.UnsignedLongTy : Context.LongTy); 6155 } else { 6156 BestWidth = Context.Target.getLongLongWidth(); 6157 assert(NumPositiveBits <= BestWidth && 6158 "How could an initializer get larger than ULL?"); 6159 BestType = Context.UnsignedLongLongTy; 6160 BestPromotionType = (NumPositiveBits == BestWidth 6161 ? Context.UnsignedLongLongTy : Context.LongLongTy); 6162 } 6163 } 6164 6165 // If we're in C and the promotion type is larger than an int, just 6166 // use the underlying type, which is generally the unsigned integer 6167 // type of the same rank as the promotion type. This is how the gcc 6168 // extension works. 6169 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 6170 BestPromotionType = BestType; 6171 6172 // Loop over all of the enumerator constants, changing their types to match 6173 // the type of the enum if needed. 6174 for (unsigned i = 0; i != NumElements; ++i) { 6175 EnumConstantDecl *ECD = 6176 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6177 if (!ECD) continue; // Already issued a diagnostic. 6178 6179 // Standard C says the enumerators have int type, but we allow, as an 6180 // extension, the enumerators to be larger than int size. If each 6181 // enumerator value fits in an int, type it as an int, otherwise type it the 6182 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6183 // that X has type 'int', not 'unsigned'. 6184 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 6185 continue; 6186 6187 // Determine whether the value fits into an int. 6188 llvm::APSInt InitVal = ECD->getInitVal(); 6189 bool FitsInInt; 6190 if (InitVal.isUnsigned() || !InitVal.isNegative()) 6191 FitsInInt = InitVal.getActiveBits() < IntWidth; 6192 else 6193 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 6194 6195 // If it fits into an integer type, force it. Otherwise force it to match 6196 // the enum decl type. 6197 QualType NewTy; 6198 unsigned NewWidth; 6199 bool NewSign; 6200 if (FitsInInt && !getLangOptions().CPlusPlus) { 6201 NewTy = Context.IntTy; 6202 NewWidth = IntWidth; 6203 NewSign = true; 6204 } else if (ECD->getType() == BestType) { 6205 // Already the right type! 6206 if (getLangOptions().CPlusPlus) 6207 // C++ [dcl.enum]p4: Following the closing brace of an 6208 // enum-specifier, each enumerator has the type of its 6209 // enumeration. 6210 ECD->setType(EnumType); 6211 continue; 6212 } else { 6213 NewTy = BestType; 6214 NewWidth = BestWidth; 6215 NewSign = BestType->isSignedIntegerType(); 6216 } 6217 6218 // Adjust the APSInt value. 6219 InitVal.extOrTrunc(NewWidth); 6220 InitVal.setIsSigned(NewSign); 6221 ECD->setInitVal(InitVal); 6222 6223 // Adjust the Expr initializer and type. 6224 if (ECD->getInitExpr()) 6225 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6226 CastExpr::CK_IntegralCast, 6227 ECD->getInitExpr(), 6228 /*isLvalue=*/false)); 6229 if (getLangOptions().CPlusPlus) 6230 // C++ [dcl.enum]p4: Following the closing brace of an 6231 // enum-specifier, each enumerator has the type of its 6232 // enumeration. 6233 ECD->setType(EnumType); 6234 else 6235 ECD->setType(NewTy); 6236 } 6237 6238 Enum->completeDefinition(Context, BestType, BestPromotionType); 6239} 6240 6241Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6242 ExprArg expr) { 6243 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6244 6245 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6246 Loc, AsmString); 6247 CurContext->addDecl(New); 6248 return DeclPtrTy::make(New); 6249} 6250 6251void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6252 SourceLocation PragmaLoc, 6253 SourceLocation NameLoc) { 6254 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6255 6256 if (PrevDecl) { 6257 PrevDecl->addAttr(::new (Context) WeakAttr()); 6258 } else { 6259 (void)WeakUndeclaredIdentifiers.insert( 6260 std::pair<IdentifierInfo*,WeakInfo> 6261 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6262 } 6263} 6264 6265void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6266 IdentifierInfo* AliasName, 6267 SourceLocation PragmaLoc, 6268 SourceLocation NameLoc, 6269 SourceLocation AliasNameLoc) { 6270 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6271 WeakInfo W = WeakInfo(Name, NameLoc); 6272 6273 if (PrevDecl) { 6274 if (!PrevDecl->hasAttr<AliasAttr>()) 6275 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6276 DeclApplyPragmaWeak(TUScope, ND, W); 6277 } else { 6278 (void)WeakUndeclaredIdentifiers.insert( 6279 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6280 } 6281} 6282