SemaDecl.cpp revision e15e62c2544d5fe5a98bdcd33e07d50458098516
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/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/Analysis/CFG.h" 21#include "clang/AST/CXXInheritance.h" 22#include "clang/AST/DeclObjC.h" 23#include "clang/AST/DeclTemplate.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/StmtCXX.h" 26#include "clang/AST/StmtObjC.h" 27#include "clang/Parse/DeclSpec.h" 28#include "clang/Parse/ParseDiagnostic.h" 29#include "clang/Parse/Template.h" 30#include "clang/Basic/PartialDiagnostic.h" 31#include "clang/Basic/SourceManager.h" 32#include "clang/Basic/TargetInfo.h" 33// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 34#include "clang/Lex/Preprocessor.h" 35#include "clang/Lex/HeaderSearch.h" 36#include "llvm/ADT/BitVector.h" 37#include "llvm/ADT/STLExtras.h" 38#include "llvm/ADT/Triple.h" 39#include <algorithm> 40#include <cstring> 41#include <functional> 42#include <queue> 43using namespace clang; 44 45/// getDeclName - Return a pretty name for the specified decl if possible, or 46/// an empty string if not. This is used for pretty crash reporting. 47std::string Sema::getDeclName(DeclPtrTy d) { 48 Decl *D = d.getAs<Decl>(); 49 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 50 return DN->getQualifiedNameAsString(); 51 return ""; 52} 53 54Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 55 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 56} 57 58/// \brief If the identifier refers to a type name within this scope, 59/// return the declaration of that type. 60/// 61/// This routine performs ordinary name lookup of the identifier II 62/// within the given scope, with optional C++ scope specifier SS, to 63/// determine whether the name refers to a type. If so, returns an 64/// opaque pointer (actually a QualType) corresponding to that 65/// type. Otherwise, returns NULL. 66/// 67/// If name lookup results in an ambiguity, this routine will complain 68/// and then return NULL. 69Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 70 Scope *S, const CXXScopeSpec *SS, 71 bool isClassName, 72 TypeTy *ObjectTypePtr) { 73 // Determine where we will perform name lookup. 74 DeclContext *LookupCtx = 0; 75 if (ObjectTypePtr) { 76 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 77 if (ObjectType->isRecordType()) 78 LookupCtx = computeDeclContext(ObjectType); 79 } else if (SS && SS->isSet()) { 80 LookupCtx = computeDeclContext(*SS, false); 81 82 if (!LookupCtx) { 83 if (isDependentScopeSpecifier(*SS)) { 84 // C++ [temp.res]p3: 85 // A qualified-id that refers to a type and in which the 86 // nested-name-specifier depends on a template-parameter (14.6.2) 87 // shall be prefixed by the keyword typename to indicate that the 88 // qualified-id denotes a type, forming an 89 // elaborated-type-specifier (7.1.5.3). 90 // 91 // We therefore do not perform any name lookup if the result would 92 // refer to a member of an unknown specialization. 93 if (!isClassName) 94 return 0; 95 96 // We know from the grammar that this name refers to a type, so build a 97 // TypenameType node to describe the type. 98 // FIXME: Record somewhere that this TypenameType node has no "typename" 99 // keyword associated with it. 100 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 101 II, SS->getRange()).getAsOpaquePtr(); 102 } 103 104 return 0; 105 } 106 107 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 108 return 0; 109 } 110 111 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 112 // lookup for class-names. 113 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 114 LookupOrdinaryName; 115 LookupResult Result(*this, &II, NameLoc, Kind); 116 if (LookupCtx) { 117 // Perform "qualified" name lookup into the declaration context we 118 // computed, which is either the type of the base of a member access 119 // expression or the declaration context associated with a prior 120 // nested-name-specifier. 121 LookupQualifiedName(Result, LookupCtx); 122 123 if (ObjectTypePtr && Result.empty()) { 124 // C++ [basic.lookup.classref]p3: 125 // If the unqualified-id is ~type-name, the type-name is looked up 126 // in the context of the entire postfix-expression. If the type T of 127 // the object expression is of a class type C, the type-name is also 128 // looked up in the scope of class C. At least one of the lookups shall 129 // find a name that refers to (possibly cv-qualified) T. 130 LookupName(Result, S); 131 } 132 } else { 133 // Perform unqualified name lookup. 134 LookupName(Result, S); 135 } 136 137 NamedDecl *IIDecl = 0; 138 switch (Result.getResultKind()) { 139 case LookupResult::NotFound: 140 case LookupResult::FoundOverloaded: 141 case LookupResult::FoundUnresolvedValue: 142 return 0; 143 144 case LookupResult::Ambiguous: 145 // Recover from type-hiding ambiguities by hiding the type. We'll 146 // do the lookup again when looking for an object, and we can 147 // diagnose the error then. If we don't do this, then the error 148 // about hiding the type will be immediately followed by an error 149 // that only makes sense if the identifier was treated like a type. 150 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 151 Result.suppressDiagnostics(); 152 return 0; 153 } 154 155 // Look to see if we have a type anywhere in the list of results. 156 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 157 Res != ResEnd; ++Res) { 158 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 159 if (!IIDecl || 160 (*Res)->getLocation().getRawEncoding() < 161 IIDecl->getLocation().getRawEncoding()) 162 IIDecl = *Res; 163 } 164 } 165 166 if (!IIDecl) { 167 // None of the entities we found is a type, so there is no way 168 // to even assume that the result is a type. In this case, don't 169 // complain about the ambiguity. The parser will either try to 170 // perform this lookup again (e.g., as an object name), which 171 // will produce the ambiguity, or will complain that it expected 172 // a type name. 173 Result.suppressDiagnostics(); 174 return 0; 175 } 176 177 // We found a type within the ambiguous lookup; diagnose the 178 // ambiguity and then return that type. This might be the right 179 // answer, or it might not be, but it suppresses any attempt to 180 // perform the name lookup again. 181 break; 182 183 case LookupResult::Found: 184 IIDecl = Result.getFoundDecl(); 185 break; 186 } 187 188 assert(IIDecl && "Didn't find decl"); 189 190 QualType T; 191 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 192 DiagnoseUseOfDecl(IIDecl, NameLoc); 193 194 // C++ [temp.local]p2: 195 // Within the scope of a class template specialization or 196 // partial specialization, when the injected-class-name is 197 // not followed by a <, it is equivalent to the 198 // injected-class-name followed by the template-argument s 199 // of the class template specialization or partial 200 // specialization enclosed in <>. 201 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 202 if (RD->isInjectedClassName()) 203 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 204 T = Template->getInjectedClassNameType(Context); 205 206 if (T.isNull()) 207 T = Context.getTypeDeclType(TD); 208 209 if (SS) 210 T = getQualifiedNameType(*SS, T); 211 212 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 213 T = Context.getObjCInterfaceType(IDecl); 214 } else if (UnresolvedUsingTypenameDecl *UUDecl = 215 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 216 // FIXME: preserve source structure information. 217 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 218 } else { 219 // If it's not plausibly a type, suppress diagnostics. 220 Result.suppressDiagnostics(); 221 return 0; 222 } 223 224 return T.getAsOpaquePtr(); 225} 226 227/// isTagName() - This method is called *for error recovery purposes only* 228/// to determine if the specified name is a valid tag name ("struct foo"). If 229/// so, this returns the TST for the tag corresponding to it (TST_enum, 230/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 231/// where the user forgot to specify the tag. 232DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 233 // Do a tag name lookup in this scope. 234 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 235 LookupName(R, S, false); 236 R.suppressDiagnostics(); 237 if (R.getResultKind() == LookupResult::Found) 238 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 239 switch (TD->getTagKind()) { 240 case TagDecl::TK_struct: return DeclSpec::TST_struct; 241 case TagDecl::TK_union: return DeclSpec::TST_union; 242 case TagDecl::TK_class: return DeclSpec::TST_class; 243 case TagDecl::TK_enum: return DeclSpec::TST_enum; 244 } 245 } 246 247 return DeclSpec::TST_unspecified; 248} 249 250bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 251 SourceLocation IILoc, 252 Scope *S, 253 const CXXScopeSpec *SS, 254 TypeTy *&SuggestedType) { 255 // We don't have anything to suggest (yet). 256 SuggestedType = 0; 257 258 // There may have been a typo in the name of the type. Look up typo 259 // results, in case we have something that we can suggest. 260 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 261 NotForRedeclaration); 262 263 // FIXME: It would be nice if we could correct for typos in built-in 264 // names, such as "itn" for "int". 265 266 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 267 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 268 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 269 !Result->isInvalidDecl()) { 270 // We found a similarly-named type or interface; suggest that. 271 if (!SS || !SS->isSet()) 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Lookup.getLookupName() 274 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 275 Result->getNameAsString()); 276 else if (DeclContext *DC = computeDeclContext(*SS, false)) 277 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 278 << &II << DC << Lookup.getLookupName() << SS->getRange() 279 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 280 Result->getNameAsString()); 281 else 282 llvm_unreachable("could not have corrected a typo here"); 283 284 Diag(Result->getLocation(), diag::note_previous_decl) 285 << Result->getDeclName(); 286 287 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 288 return true; 289 } 290 } 291 292 // FIXME: Should we move the logic that tries to recover from a missing tag 293 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 294 295 if (!SS || (!SS->isSet() && !SS->isInvalid())) 296 Diag(IILoc, diag::err_unknown_typename) << &II; 297 else if (DeclContext *DC = computeDeclContext(*SS, false)) 298 Diag(IILoc, diag::err_typename_nested_not_found) 299 << &II << DC << SS->getRange(); 300 else if (isDependentScopeSpecifier(*SS)) { 301 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 302 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 303 << SourceRange(SS->getRange().getBegin(), IILoc) 304 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 305 "typename "); 306 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 307 } else { 308 assert(SS && SS->isInvalid() && 309 "Invalid scope specifier has already been diagnosed"); 310 } 311 312 return true; 313} 314 315// Determines the context to return to after temporarily entering a 316// context. This depends in an unnecessarily complicated way on the 317// exact ordering of callbacks from the parser. 318DeclContext *Sema::getContainingDC(DeclContext *DC) { 319 320 // Functions defined inline within classes aren't parsed until we've 321 // finished parsing the top-level class, so the top-level class is 322 // the context we'll need to return to. 323 if (isa<FunctionDecl>(DC)) { 324 DC = DC->getLexicalParent(); 325 326 // A function not defined within a class will always return to its 327 // lexical context. 328 if (!isa<CXXRecordDecl>(DC)) 329 return DC; 330 331 // A C++ inline method/friend is parsed *after* the topmost class 332 // it was declared in is fully parsed ("complete"); the topmost 333 // class is the context we need to return to. 334 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 335 DC = RD; 336 337 // Return the declaration context of the topmost class the inline method is 338 // declared in. 339 return DC; 340 } 341 342 if (isa<ObjCMethodDecl>(DC)) 343 return Context.getTranslationUnitDecl(); 344 345 return DC->getLexicalParent(); 346} 347 348void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 349 assert(getContainingDC(DC) == CurContext && 350 "The next DeclContext should be lexically contained in the current one."); 351 CurContext = DC; 352 S->setEntity(DC); 353} 354 355void Sema::PopDeclContext() { 356 assert(CurContext && "DeclContext imbalance!"); 357 358 CurContext = getContainingDC(CurContext); 359} 360 361/// EnterDeclaratorContext - Used when we must lookup names in the context 362/// of a declarator's nested name specifier. 363/// 364void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 365 // C++0x [basic.lookup.unqual]p13: 366 // A name used in the definition of a static data member of class 367 // X (after the qualified-id of the static member) is looked up as 368 // if the name was used in a member function of X. 369 // C++0x [basic.lookup.unqual]p14: 370 // If a variable member of a namespace is defined outside of the 371 // scope of its namespace then any name used in the definition of 372 // the variable member (after the declarator-id) is looked up as 373 // if the definition of the variable member occurred in its 374 // namespace. 375 // Both of these imply that we should push a scope whose context 376 // is the semantic context of the declaration. We can't use 377 // PushDeclContext here because that context is not necessarily 378 // lexically contained in the current context. Fortunately, 379 // the containing scope should have the appropriate information. 380 381 assert(!S->getEntity() && "scope already has entity"); 382 383#ifndef NDEBUG 384 Scope *Ancestor = S->getParent(); 385 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 386 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 387#endif 388 389 CurContext = DC; 390 S->setEntity(DC); 391} 392 393void Sema::ExitDeclaratorContext(Scope *S) { 394 assert(S->getEntity() == CurContext && "Context imbalance!"); 395 396 // Switch back to the lexical context. The safety of this is 397 // enforced by an assert in EnterDeclaratorContext. 398 Scope *Ancestor = S->getParent(); 399 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 400 CurContext = (DeclContext*) Ancestor->getEntity(); 401 402 // We don't need to do anything with the scope, which is going to 403 // disappear. 404} 405 406/// \brief Determine whether we allow overloading of the function 407/// PrevDecl with another declaration. 408/// 409/// This routine determines whether overloading is possible, not 410/// whether some new function is actually an overload. It will return 411/// true in C++ (where we can always provide overloads) or, as an 412/// extension, in C when the previous function is already an 413/// overloaded function declaration or has the "overloadable" 414/// attribute. 415static bool AllowOverloadingOfFunction(LookupResult &Previous, 416 ASTContext &Context) { 417 if (Context.getLangOptions().CPlusPlus) 418 return true; 419 420 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 421 return true; 422 423 return (Previous.getResultKind() == LookupResult::Found 424 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 425} 426 427/// Add this decl to the scope shadowed decl chains. 428void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 429 // Move up the scope chain until we find the nearest enclosing 430 // non-transparent context. The declaration will be introduced into this 431 // scope. 432 while (S->getEntity() && 433 ((DeclContext *)S->getEntity())->isTransparentContext()) 434 S = S->getParent(); 435 436 // Add scoped declarations into their context, so that they can be 437 // found later. Declarations without a context won't be inserted 438 // into any context. 439 if (AddToContext) 440 CurContext->addDecl(D); 441 442 // Out-of-line function and variable definitions should not be pushed into 443 // scope. 444 if ((isa<FunctionTemplateDecl>(D) && 445 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 446 (isa<FunctionDecl>(D) && 447 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 448 cast<FunctionDecl>(D)->isOutOfLine())) || 449 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 450 return; 451 452 // If this replaces anything in the current scope, 453 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 454 IEnd = IdResolver.end(); 455 for (; I != IEnd; ++I) { 456 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 457 S->RemoveDecl(DeclPtrTy::make(*I)); 458 IdResolver.RemoveDecl(*I); 459 460 // Should only need to replace one decl. 461 break; 462 } 463 } 464 465 S->AddDecl(DeclPtrTy::make(D)); 466 IdResolver.AddDecl(D); 467} 468 469bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 470 return IdResolver.isDeclInScope(D, Ctx, Context, S); 471} 472 473static bool isOutOfScopePreviousDeclaration(NamedDecl *, 474 DeclContext*, 475 ASTContext&); 476 477/// Filters out lookup results that don't fall within the given scope 478/// as determined by isDeclInScope. 479static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 480 DeclContext *Ctx, Scope *S, 481 bool ConsiderLinkage) { 482 LookupResult::Filter F = R.makeFilter(); 483 while (F.hasNext()) { 484 NamedDecl *D = F.next(); 485 486 if (SemaRef.isDeclInScope(D, Ctx, S)) 487 continue; 488 489 if (ConsiderLinkage && 490 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 491 continue; 492 493 F.erase(); 494 } 495 496 F.done(); 497} 498 499static bool isUsingDecl(NamedDecl *D) { 500 return isa<UsingShadowDecl>(D) || 501 isa<UnresolvedUsingTypenameDecl>(D) || 502 isa<UnresolvedUsingValueDecl>(D); 503} 504 505/// Removes using shadow declarations from the lookup results. 506static void RemoveUsingDecls(LookupResult &R) { 507 LookupResult::Filter F = R.makeFilter(); 508 while (F.hasNext()) 509 if (isUsingDecl(F.next())) 510 F.erase(); 511 512 F.done(); 513} 514 515static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 516 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 517 return false; 518 519 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 520 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 521 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 522 if (!RD->hasTrivialConstructor()) 523 return false; 524 if (!RD->hasTrivialDestructor()) 525 return false; 526 } 527 } 528 } 529 530 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 531 !isa<ImplicitParamDecl>(D) && 532 D->getDeclContext()->isFunctionOrMethod()); 533} 534 535void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 536 if (S->decl_empty()) return; 537 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 538 "Scope shouldn't contain decls!"); 539 540 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 541 I != E; ++I) { 542 Decl *TmpD = (*I).getAs<Decl>(); 543 assert(TmpD && "This decl didn't get pushed??"); 544 545 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 546 NamedDecl *D = cast<NamedDecl>(TmpD); 547 548 if (!D->getDeclName()) continue; 549 550 // Diagnose unused variables in this scope. 551 if (ShouldDiagnoseUnusedDecl(D)) 552 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 553 554 // Remove this name from our lexical scope. 555 IdResolver.RemoveDecl(D); 556 } 557} 558 559/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 560/// return 0 if one not found. 561/// 562/// \param Id the name of the Objective-C class we're looking for. If 563/// typo-correction fixes this name, the Id will be updated 564/// to the fixed name. 565/// 566/// \param RecoverLoc if provided, this routine will attempt to 567/// recover from a typo in the name of an existing Objective-C class 568/// and, if successful, will return the lookup that results from 569/// typo-correction. 570ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 571 SourceLocation RecoverLoc) { 572 // The third "scope" argument is 0 since we aren't enabling lazy built-in 573 // creation from this context. 574 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 575 576 if (!IDecl && !RecoverLoc.isInvalid()) { 577 // Perform typo correction at the given location, but only if we 578 // find an Objective-C class name. 579 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 580 if (CorrectTypo(R, TUScope, 0) && 581 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 582 Diag(RecoverLoc, diag::err_undef_interface_suggest) 583 << Id << IDecl->getDeclName() 584 << CodeModificationHint::CreateReplacement(RecoverLoc, 585 IDecl->getNameAsString()); 586 Diag(IDecl->getLocation(), diag::note_previous_decl) 587 << IDecl->getDeclName(); 588 589 Id = IDecl->getIdentifier(); 590 } 591 } 592 593 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 594} 595 596/// getNonFieldDeclScope - Retrieves the innermost scope, starting 597/// from S, where a non-field would be declared. This routine copes 598/// with the difference between C and C++ scoping rules in structs and 599/// unions. For example, the following code is well-formed in C but 600/// ill-formed in C++: 601/// @code 602/// struct S6 { 603/// enum { BAR } e; 604/// }; 605/// 606/// void test_S6() { 607/// struct S6 a; 608/// a.e = BAR; 609/// } 610/// @endcode 611/// For the declaration of BAR, this routine will return a different 612/// scope. The scope S will be the scope of the unnamed enumeration 613/// within S6. In C++, this routine will return the scope associated 614/// with S6, because the enumeration's scope is a transparent 615/// context but structures can contain non-field names. In C, this 616/// routine will return the translation unit scope, since the 617/// enumeration's scope is a transparent context and structures cannot 618/// contain non-field names. 619Scope *Sema::getNonFieldDeclScope(Scope *S) { 620 while (((S->getFlags() & Scope::DeclScope) == 0) || 621 (S->getEntity() && 622 ((DeclContext *)S->getEntity())->isTransparentContext()) || 623 (S->isClassScope() && !getLangOptions().CPlusPlus)) 624 S = S->getParent(); 625 return S; 626} 627 628void Sema::InitBuiltinVaListType() { 629 if (!Context.getBuiltinVaListType().isNull()) 630 return; 631 632 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 633 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 634 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 635 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 636} 637 638/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 639/// file scope. lazily create a decl for it. ForRedeclaration is true 640/// if we're creating this built-in in anticipation of redeclaring the 641/// built-in. 642NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 643 Scope *S, bool ForRedeclaration, 644 SourceLocation Loc) { 645 Builtin::ID BID = (Builtin::ID)bid; 646 647 if (Context.BuiltinInfo.hasVAListUse(BID)) 648 InitBuiltinVaListType(); 649 650 ASTContext::GetBuiltinTypeError Error; 651 QualType R = Context.GetBuiltinType(BID, Error); 652 switch (Error) { 653 case ASTContext::GE_None: 654 // Okay 655 break; 656 657 case ASTContext::GE_Missing_stdio: 658 if (ForRedeclaration) 659 Diag(Loc, diag::err_implicit_decl_requires_stdio) 660 << Context.BuiltinInfo.GetName(BID); 661 return 0; 662 663 case ASTContext::GE_Missing_setjmp: 664 if (ForRedeclaration) 665 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 666 << Context.BuiltinInfo.GetName(BID); 667 return 0; 668 } 669 670 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 671 Diag(Loc, diag::ext_implicit_lib_function_decl) 672 << Context.BuiltinInfo.GetName(BID) 673 << R; 674 if (Context.BuiltinInfo.getHeaderName(BID) && 675 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 676 != Diagnostic::Ignored) 677 Diag(Loc, diag::note_please_include_header) 678 << Context.BuiltinInfo.getHeaderName(BID) 679 << Context.BuiltinInfo.GetName(BID); 680 } 681 682 FunctionDecl *New = FunctionDecl::Create(Context, 683 Context.getTranslationUnitDecl(), 684 Loc, II, R, /*TInfo=*/0, 685 FunctionDecl::Extern, false, 686 /*hasPrototype=*/true); 687 New->setImplicit(); 688 689 // Create Decl objects for each parameter, adding them to the 690 // FunctionDecl. 691 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 692 llvm::SmallVector<ParmVarDecl*, 16> Params; 693 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 694 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 695 FT->getArgType(i), /*TInfo=*/0, 696 VarDecl::None, 0)); 697 New->setParams(Context, Params.data(), Params.size()); 698 } 699 700 AddKnownFunctionAttributes(New); 701 702 // TUScope is the translation-unit scope to insert this function into. 703 // FIXME: This is hideous. We need to teach PushOnScopeChains to 704 // relate Scopes to DeclContexts, and probably eliminate CurContext 705 // entirely, but we're not there yet. 706 DeclContext *SavedContext = CurContext; 707 CurContext = Context.getTranslationUnitDecl(); 708 PushOnScopeChains(New, TUScope); 709 CurContext = SavedContext; 710 return New; 711} 712 713/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 714/// same name and scope as a previous declaration 'Old'. Figure out 715/// how to resolve this situation, merging decls or emitting 716/// diagnostics as appropriate. If there was an error, set New to be invalid. 717/// 718void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 719 // If the new decl is known invalid already, don't bother doing any 720 // merging checks. 721 if (New->isInvalidDecl()) return; 722 723 // Allow multiple definitions for ObjC built-in typedefs. 724 // FIXME: Verify the underlying types are equivalent! 725 if (getLangOptions().ObjC1) { 726 const IdentifierInfo *TypeID = New->getIdentifier(); 727 switch (TypeID->getLength()) { 728 default: break; 729 case 2: 730 if (!TypeID->isStr("id")) 731 break; 732 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 733 // Install the built-in type for 'id', ignoring the current definition. 734 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 735 return; 736 case 5: 737 if (!TypeID->isStr("Class")) 738 break; 739 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 740 // Install the built-in type for 'Class', ignoring the current definition. 741 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 742 return; 743 case 3: 744 if (!TypeID->isStr("SEL")) 745 break; 746 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 747 // Install the built-in type for 'SEL', ignoring the current definition. 748 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 749 return; 750 case 8: 751 if (!TypeID->isStr("Protocol")) 752 break; 753 Context.setObjCProtoType(New->getUnderlyingType()); 754 return; 755 } 756 // Fall through - the typedef name was not a builtin type. 757 } 758 759 // Verify the old decl was also a type. 760 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 761 if (!Old) { 762 Diag(New->getLocation(), diag::err_redefinition_different_kind) 763 << New->getDeclName(); 764 765 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 766 if (OldD->getLocation().isValid()) 767 Diag(OldD->getLocation(), diag::note_previous_definition); 768 769 return New->setInvalidDecl(); 770 } 771 772 // If the old declaration is invalid, just give up here. 773 if (Old->isInvalidDecl()) 774 return New->setInvalidDecl(); 775 776 // Determine the "old" type we'll use for checking and diagnostics. 777 QualType OldType; 778 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 779 OldType = OldTypedef->getUnderlyingType(); 780 else 781 OldType = Context.getTypeDeclType(Old); 782 783 // If the typedef types are not identical, reject them in all languages and 784 // with any extensions enabled. 785 786 if (OldType != New->getUnderlyingType() && 787 Context.getCanonicalType(OldType) != 788 Context.getCanonicalType(New->getUnderlyingType())) { 789 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 790 << New->getUnderlyingType() << OldType; 791 if (Old->getLocation().isValid()) 792 Diag(Old->getLocation(), diag::note_previous_definition); 793 return New->setInvalidDecl(); 794 } 795 796 // The types match. Link up the redeclaration chain if the old 797 // declaration was a typedef. 798 // FIXME: this is a potential source of wierdness if the type 799 // spellings don't match exactly. 800 if (isa<TypedefDecl>(Old)) 801 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 802 803 if (getLangOptions().Microsoft) 804 return; 805 806 if (getLangOptions().CPlusPlus) { 807 // C++ [dcl.typedef]p2: 808 // In a given non-class scope, a typedef specifier can be used to 809 // redefine the name of any type declared in that scope to refer 810 // to the type to which it already refers. 811 if (!isa<CXXRecordDecl>(CurContext)) 812 return; 813 814 // C++0x [dcl.typedef]p4: 815 // In a given class scope, a typedef specifier can be used to redefine 816 // any class-name declared in that scope that is not also a typedef-name 817 // to refer to the type to which it already refers. 818 // 819 // This wording came in via DR424, which was a correction to the 820 // wording in DR56, which accidentally banned code like: 821 // 822 // struct S { 823 // typedef struct A { } A; 824 // }; 825 // 826 // in the C++03 standard. We implement the C++0x semantics, which 827 // allow the above but disallow 828 // 829 // struct S { 830 // typedef int I; 831 // typedef int I; 832 // }; 833 // 834 // since that was the intent of DR56. 835 if (isa<ElaboratedType>(New->getUnderlyingType())) 836 return; 837 838 Diag(New->getLocation(), diag::err_redefinition) 839 << New->getDeclName(); 840 Diag(Old->getLocation(), diag::note_previous_definition); 841 return New->setInvalidDecl(); 842 } 843 844 // If we have a redefinition of a typedef in C, emit a warning. This warning 845 // is normally mapped to an error, but can be controlled with 846 // -Wtypedef-redefinition. If either the original or the redefinition is 847 // in a system header, don't emit this for compatibility with GCC. 848 if (PP.getDiagnostics().getSuppressSystemWarnings() && 849 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 850 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 851 return; 852 853 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 854 << New->getDeclName(); 855 Diag(Old->getLocation(), diag::note_previous_definition); 856 return; 857} 858 859/// DeclhasAttr - returns true if decl Declaration already has the target 860/// attribute. 861static bool 862DeclHasAttr(const Decl *decl, const Attr *target) { 863 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 864 if (attr->getKind() == target->getKind()) 865 return true; 866 867 return false; 868} 869 870/// MergeAttributes - append attributes from the Old decl to the New one. 871static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 872 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 873 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 874 Attr *NewAttr = attr->clone(C); 875 NewAttr->setInherited(true); 876 New->addAttr(NewAttr); 877 } 878 } 879} 880 881/// Used in MergeFunctionDecl to keep track of function parameters in 882/// C. 883struct GNUCompatibleParamWarning { 884 ParmVarDecl *OldParm; 885 ParmVarDecl *NewParm; 886 QualType PromotedType; 887}; 888 889 890/// getSpecialMember - get the special member enum for a method. 891static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 892 const CXXMethodDecl *MD) { 893 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 894 if (Ctor->isDefaultConstructor()) 895 return Sema::CXXDefaultConstructor; 896 if (Ctor->isCopyConstructor()) 897 return Sema::CXXCopyConstructor; 898 } 899 900 if (isa<CXXDestructorDecl>(MD)) 901 return Sema::CXXDestructor; 902 903 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 904 return Sema::CXXCopyAssignment; 905} 906 907/// MergeFunctionDecl - We just parsed a function 'New' from 908/// declarator D which has the same name and scope as a previous 909/// declaration 'Old'. Figure out how to resolve this situation, 910/// merging decls or emitting diagnostics as appropriate. 911/// 912/// In C++, New and Old must be declarations that are not 913/// overloaded. Use IsOverload to determine whether New and Old are 914/// overloaded, and to select the Old declaration that New should be 915/// merged with. 916/// 917/// Returns true if there was an error, false otherwise. 918bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 919 // Verify the old decl was also a function. 920 FunctionDecl *Old = 0; 921 if (FunctionTemplateDecl *OldFunctionTemplate 922 = dyn_cast<FunctionTemplateDecl>(OldD)) 923 Old = OldFunctionTemplate->getTemplatedDecl(); 924 else 925 Old = dyn_cast<FunctionDecl>(OldD); 926 if (!Old) { 927 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 928 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 929 Diag(Shadow->getTargetDecl()->getLocation(), 930 diag::note_using_decl_target); 931 Diag(Shadow->getUsingDecl()->getLocation(), 932 diag::note_using_decl) << 0; 933 return true; 934 } 935 936 Diag(New->getLocation(), diag::err_redefinition_different_kind) 937 << New->getDeclName(); 938 Diag(OldD->getLocation(), diag::note_previous_definition); 939 return true; 940 } 941 942 // Determine whether the previous declaration was a definition, 943 // implicit declaration, or a declaration. 944 diag::kind PrevDiag; 945 if (Old->isThisDeclarationADefinition()) 946 PrevDiag = diag::note_previous_definition; 947 else if (Old->isImplicit()) 948 PrevDiag = diag::note_previous_implicit_declaration; 949 else 950 PrevDiag = diag::note_previous_declaration; 951 952 QualType OldQType = Context.getCanonicalType(Old->getType()); 953 QualType NewQType = Context.getCanonicalType(New->getType()); 954 955 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 956 New->getStorageClass() == FunctionDecl::Static && 957 Old->getStorageClass() != FunctionDecl::Static) { 958 Diag(New->getLocation(), diag::err_static_non_static) 959 << New; 960 Diag(Old->getLocation(), PrevDiag); 961 return true; 962 } 963 964 if (getLangOptions().CPlusPlus) { 965 // (C++98 13.1p2): 966 // Certain function declarations cannot be overloaded: 967 // -- Function declarations that differ only in the return type 968 // cannot be overloaded. 969 QualType OldReturnType 970 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 971 QualType NewReturnType 972 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 973 if (OldReturnType != NewReturnType) { 974 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 975 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 976 return true; 977 } 978 979 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 980 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 981 if (OldMethod && NewMethod) { 982 if (!NewMethod->getFriendObjectKind() && 983 NewMethod->getLexicalDeclContext()->isRecord()) { 984 // -- Member function declarations with the same name and the 985 // same parameter types cannot be overloaded if any of them 986 // is a static member function declaration. 987 if (OldMethod->isStatic() || NewMethod->isStatic()) { 988 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 989 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 990 return true; 991 } 992 993 // C++ [class.mem]p1: 994 // [...] A member shall not be declared twice in the 995 // member-specification, except that a nested class or member 996 // class template can be declared and then later defined. 997 unsigned NewDiag; 998 if (isa<CXXConstructorDecl>(OldMethod)) 999 NewDiag = diag::err_constructor_redeclared; 1000 else if (isa<CXXDestructorDecl>(NewMethod)) 1001 NewDiag = diag::err_destructor_redeclared; 1002 else if (isa<CXXConversionDecl>(NewMethod)) 1003 NewDiag = diag::err_conv_function_redeclared; 1004 else 1005 NewDiag = diag::err_member_redeclared; 1006 1007 Diag(New->getLocation(), NewDiag); 1008 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1009 } else { 1010 if (OldMethod->isImplicit()) { 1011 Diag(NewMethod->getLocation(), 1012 diag::err_definition_of_implicitly_declared_member) 1013 << New << getSpecialMember(Context, OldMethod); 1014 1015 Diag(OldMethod->getLocation(), 1016 diag::note_previous_implicit_declaration); 1017 return true; 1018 } 1019 } 1020 } 1021 1022 // (C++98 8.3.5p3): 1023 // All declarations for a function shall agree exactly in both the 1024 // return type and the parameter-type-list. 1025 // attributes should be ignored when comparing. 1026 if (Context.getNoReturnType(OldQType, false) == 1027 Context.getNoReturnType(NewQType, false)) 1028 return MergeCompatibleFunctionDecls(New, Old); 1029 1030 // Fall through for conflicting redeclarations and redefinitions. 1031 } 1032 1033 // C: Function types need to be compatible, not identical. This handles 1034 // duplicate function decls like "void f(int); void f(enum X);" properly. 1035 if (!getLangOptions().CPlusPlus && 1036 Context.typesAreCompatible(OldQType, NewQType)) { 1037 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1038 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1039 const FunctionProtoType *OldProto = 0; 1040 if (isa<FunctionNoProtoType>(NewFuncType) && 1041 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1042 // The old declaration provided a function prototype, but the 1043 // new declaration does not. Merge in the prototype. 1044 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1045 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1046 OldProto->arg_type_end()); 1047 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1048 ParamTypes.data(), ParamTypes.size(), 1049 OldProto->isVariadic(), 1050 OldProto->getTypeQuals()); 1051 New->setType(NewQType); 1052 New->setHasInheritedPrototype(); 1053 1054 // Synthesize a parameter for each argument type. 1055 llvm::SmallVector<ParmVarDecl*, 16> Params; 1056 for (FunctionProtoType::arg_type_iterator 1057 ParamType = OldProto->arg_type_begin(), 1058 ParamEnd = OldProto->arg_type_end(); 1059 ParamType != ParamEnd; ++ParamType) { 1060 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1061 SourceLocation(), 0, 1062 *ParamType, /*TInfo=*/0, 1063 VarDecl::None, 0); 1064 Param->setImplicit(); 1065 Params.push_back(Param); 1066 } 1067 1068 New->setParams(Context, Params.data(), Params.size()); 1069 } 1070 1071 return MergeCompatibleFunctionDecls(New, Old); 1072 } 1073 1074 // GNU C permits a K&R definition to follow a prototype declaration 1075 // if the declared types of the parameters in the K&R definition 1076 // match the types in the prototype declaration, even when the 1077 // promoted types of the parameters from the K&R definition differ 1078 // from the types in the prototype. GCC then keeps the types from 1079 // the prototype. 1080 // 1081 // If a variadic prototype is followed by a non-variadic K&R definition, 1082 // the K&R definition becomes variadic. This is sort of an edge case, but 1083 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1084 // C99 6.9.1p8. 1085 if (!getLangOptions().CPlusPlus && 1086 Old->hasPrototype() && !New->hasPrototype() && 1087 New->getType()->getAs<FunctionProtoType>() && 1088 Old->getNumParams() == New->getNumParams()) { 1089 llvm::SmallVector<QualType, 16> ArgTypes; 1090 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1091 const FunctionProtoType *OldProto 1092 = Old->getType()->getAs<FunctionProtoType>(); 1093 const FunctionProtoType *NewProto 1094 = New->getType()->getAs<FunctionProtoType>(); 1095 1096 // Determine whether this is the GNU C extension. 1097 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1098 NewProto->getResultType()); 1099 bool LooseCompatible = !MergedReturn.isNull(); 1100 for (unsigned Idx = 0, End = Old->getNumParams(); 1101 LooseCompatible && Idx != End; ++Idx) { 1102 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1103 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1104 if (Context.typesAreCompatible(OldParm->getType(), 1105 NewProto->getArgType(Idx))) { 1106 ArgTypes.push_back(NewParm->getType()); 1107 } else if (Context.typesAreCompatible(OldParm->getType(), 1108 NewParm->getType())) { 1109 GNUCompatibleParamWarning Warn 1110 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1111 Warnings.push_back(Warn); 1112 ArgTypes.push_back(NewParm->getType()); 1113 } else 1114 LooseCompatible = false; 1115 } 1116 1117 if (LooseCompatible) { 1118 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1119 Diag(Warnings[Warn].NewParm->getLocation(), 1120 diag::ext_param_promoted_not_compatible_with_prototype) 1121 << Warnings[Warn].PromotedType 1122 << Warnings[Warn].OldParm->getType(); 1123 Diag(Warnings[Warn].OldParm->getLocation(), 1124 diag::note_previous_declaration); 1125 } 1126 1127 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1128 ArgTypes.size(), 1129 OldProto->isVariadic(), 0)); 1130 return MergeCompatibleFunctionDecls(New, Old); 1131 } 1132 1133 // Fall through to diagnose conflicting types. 1134 } 1135 1136 // A function that has already been declared has been redeclared or defined 1137 // with a different type- show appropriate diagnostic 1138 if (unsigned BuiltinID = Old->getBuiltinID()) { 1139 // The user has declared a builtin function with an incompatible 1140 // signature. 1141 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1142 // The function the user is redeclaring is a library-defined 1143 // function like 'malloc' or 'printf'. Warn about the 1144 // redeclaration, then pretend that we don't know about this 1145 // library built-in. 1146 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1147 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1148 << Old << Old->getType(); 1149 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1150 Old->setInvalidDecl(); 1151 return false; 1152 } 1153 1154 PrevDiag = diag::note_previous_builtin_declaration; 1155 } 1156 1157 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1158 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1159 return true; 1160} 1161 1162/// \brief Completes the merge of two function declarations that are 1163/// known to be compatible. 1164/// 1165/// This routine handles the merging of attributes and other 1166/// properties of function declarations form the old declaration to 1167/// the new declaration, once we know that New is in fact a 1168/// redeclaration of Old. 1169/// 1170/// \returns false 1171bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1172 // Merge the attributes 1173 MergeAttributes(New, Old, Context); 1174 1175 // Merge the storage class. 1176 if (Old->getStorageClass() != FunctionDecl::Extern && 1177 Old->getStorageClass() != FunctionDecl::None) 1178 New->setStorageClass(Old->getStorageClass()); 1179 1180 // Merge "pure" flag. 1181 if (Old->isPure()) 1182 New->setPure(); 1183 1184 // Merge the "deleted" flag. 1185 if (Old->isDeleted()) 1186 New->setDeleted(); 1187 1188 if (getLangOptions().CPlusPlus) 1189 return MergeCXXFunctionDecl(New, Old); 1190 1191 return false; 1192} 1193 1194/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1195/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1196/// situation, merging decls or emitting diagnostics as appropriate. 1197/// 1198/// Tentative definition rules (C99 6.9.2p2) are checked by 1199/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1200/// definitions here, since the initializer hasn't been attached. 1201/// 1202void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1203 // If the new decl is already invalid, don't do any other checking. 1204 if (New->isInvalidDecl()) 1205 return; 1206 1207 // Verify the old decl was also a variable. 1208 VarDecl *Old = 0; 1209 if (!Previous.isSingleResult() || 1210 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1211 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1212 << New->getDeclName(); 1213 Diag(Previous.getRepresentativeDecl()->getLocation(), 1214 diag::note_previous_definition); 1215 return New->setInvalidDecl(); 1216 } 1217 1218 MergeAttributes(New, Old, Context); 1219 1220 // Merge the types 1221 QualType MergedT; 1222 if (getLangOptions().CPlusPlus) { 1223 if (Context.hasSameType(New->getType(), Old->getType())) 1224 MergedT = New->getType(); 1225 // C++ [basic.link]p10: 1226 // [...] the types specified by all declarations referring to a given 1227 // object or function shall be identical, except that declarations for an 1228 // array object can specify array types that differ by the presence or 1229 // absence of a major array bound (8.3.4). 1230 else if (Old->getType()->isIncompleteArrayType() && 1231 New->getType()->isArrayType()) { 1232 CanQual<ArrayType> OldArray 1233 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1234 CanQual<ArrayType> NewArray 1235 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1236 if (OldArray->getElementType() == NewArray->getElementType()) 1237 MergedT = New->getType(); 1238 } else if (Old->getType()->isArrayType() && 1239 New->getType()->isIncompleteArrayType()) { 1240 CanQual<ArrayType> OldArray 1241 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1242 CanQual<ArrayType> NewArray 1243 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1244 if (OldArray->getElementType() == NewArray->getElementType()) 1245 MergedT = Old->getType(); 1246 } 1247 } else { 1248 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1249 } 1250 if (MergedT.isNull()) { 1251 Diag(New->getLocation(), diag::err_redefinition_different_type) 1252 << New->getDeclName(); 1253 Diag(Old->getLocation(), diag::note_previous_definition); 1254 return New->setInvalidDecl(); 1255 } 1256 New->setType(MergedT); 1257 1258 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1259 if (New->getStorageClass() == VarDecl::Static && 1260 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1261 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1262 Diag(Old->getLocation(), diag::note_previous_definition); 1263 return New->setInvalidDecl(); 1264 } 1265 // C99 6.2.2p4: 1266 // For an identifier declared with the storage-class specifier 1267 // extern in a scope in which a prior declaration of that 1268 // identifier is visible,23) if the prior declaration specifies 1269 // internal or external linkage, the linkage of the identifier at 1270 // the later declaration is the same as the linkage specified at 1271 // the prior declaration. If no prior declaration is visible, or 1272 // if the prior declaration specifies no linkage, then the 1273 // identifier has external linkage. 1274 if (New->hasExternalStorage() && Old->hasLinkage()) 1275 /* Okay */; 1276 else if (New->getStorageClass() != VarDecl::Static && 1277 Old->getStorageClass() == VarDecl::Static) { 1278 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1279 Diag(Old->getLocation(), diag::note_previous_definition); 1280 return New->setInvalidDecl(); 1281 } 1282 1283 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1284 1285 // FIXME: The test for external storage here seems wrong? We still 1286 // need to check for mismatches. 1287 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1288 // Don't complain about out-of-line definitions of static members. 1289 !(Old->getLexicalDeclContext()->isRecord() && 1290 !New->getLexicalDeclContext()->isRecord())) { 1291 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1292 Diag(Old->getLocation(), diag::note_previous_definition); 1293 return New->setInvalidDecl(); 1294 } 1295 1296 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1297 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1298 Diag(Old->getLocation(), diag::note_previous_definition); 1299 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1300 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1301 Diag(Old->getLocation(), diag::note_previous_definition); 1302 } 1303 1304 // Keep a chain of previous declarations. 1305 New->setPreviousDeclaration(Old); 1306} 1307 1308/// CheckFallThrough - Check that we don't fall off the end of a 1309/// Statement that should return a value. 1310/// 1311/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1312/// MaybeFallThrough iff we might or might not fall off the end, 1313/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1314/// return. We assume NeverFallThrough iff we never fall off the end of the 1315/// statement but we may return. We assume that functions not marked noreturn 1316/// will return. 1317Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1318 // FIXME: Eventually share this CFG object when we have other warnings based 1319 // of the CFG. This can be done using AnalysisContext. 1320 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1321 1322 // FIXME: They should never return 0, fix that, delete this code. 1323 if (cfg == 0) 1324 // FIXME: This should be NeverFallThrough 1325 return NeverFallThroughOrReturn; 1326 // The CFG leaves in dead things, and we don't want to dead code paths to 1327 // confuse us, so we mark all live things first. 1328 std::queue<CFGBlock*> workq; 1329 llvm::BitVector live(cfg->getNumBlockIDs()); 1330 // Prep work queue 1331 workq.push(&cfg->getEntry()); 1332 // Solve 1333 while (!workq.empty()) { 1334 CFGBlock *item = workq.front(); 1335 workq.pop(); 1336 live.set(item->getBlockID()); 1337 for (CFGBlock::succ_iterator I=item->succ_begin(), 1338 E=item->succ_end(); 1339 I != E; 1340 ++I) { 1341 if ((*I) && !live[(*I)->getBlockID()]) { 1342 live.set((*I)->getBlockID()); 1343 workq.push(*I); 1344 } 1345 } 1346 } 1347 1348 // Now we know what is live, we check the live precessors of the exit block 1349 // and look for fall through paths, being careful to ignore normal returns, 1350 // and exceptional paths. 1351 bool HasLiveReturn = false; 1352 bool HasFakeEdge = false; 1353 bool HasPlainEdge = false; 1354 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1355 E = cfg->getExit().pred_end(); 1356 I != E; 1357 ++I) { 1358 CFGBlock& B = **I; 1359 if (!live[B.getBlockID()]) 1360 continue; 1361 if (B.size() == 0) { 1362 // A labeled empty statement, or the entry block... 1363 HasPlainEdge = true; 1364 continue; 1365 } 1366 Stmt *S = B[B.size()-1]; 1367 if (isa<ReturnStmt>(S)) { 1368 HasLiveReturn = true; 1369 continue; 1370 } 1371 if (isa<ObjCAtThrowStmt>(S)) { 1372 HasFakeEdge = true; 1373 continue; 1374 } 1375 if (isa<CXXThrowExpr>(S)) { 1376 HasFakeEdge = true; 1377 continue; 1378 } 1379 if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) { 1380 if (AS->isMSAsm()) { 1381 HasFakeEdge = true; 1382 HasLiveReturn = true; 1383 continue; 1384 } 1385 } 1386 1387 bool NoReturnEdge = false; 1388 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1389 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1390 if (CEE->getType().getNoReturnAttr()) { 1391 NoReturnEdge = true; 1392 HasFakeEdge = true; 1393 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1394 ValueDecl *VD = DRE->getDecl(); 1395 if (VD->hasAttr<NoReturnAttr>()) { 1396 NoReturnEdge = true; 1397 HasFakeEdge = true; 1398 } 1399 } 1400 } 1401 // FIXME: Add noreturn message sends. 1402 if (NoReturnEdge == false) 1403 HasPlainEdge = true; 1404 } 1405 if (!HasPlainEdge) { 1406 if (HasLiveReturn) 1407 return NeverFallThrough; 1408 return NeverFallThroughOrReturn; 1409 } 1410 if (HasFakeEdge || HasLiveReturn) 1411 return MaybeFallThrough; 1412 // This says AlwaysFallThrough for calls to functions that are not marked 1413 // noreturn, that don't return. If people would like this warning to be more 1414 // accurate, such functions should be marked as noreturn. 1415 return AlwaysFallThrough; 1416} 1417 1418/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1419/// function that should return a value. Check that we don't fall off the end 1420/// of a noreturn function. We assume that functions and blocks not marked 1421/// noreturn will return. 1422void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1423 // FIXME: Would be nice if we had a better way to control cascading errors, 1424 // but for now, avoid them. The problem is that when Parse sees: 1425 // int foo() { return a; } 1426 // The return is eaten and the Sema code sees just: 1427 // int foo() { } 1428 // which this code would then warn about. 1429 if (getDiagnostics().hasErrorOccurred()) 1430 return; 1431 1432 bool ReturnsVoid = false; 1433 bool HasNoReturn = false; 1434 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1435 // If the result type of the function is a dependent type, we don't know 1436 // whether it will be void or not, so don't 1437 if (FD->getResultType()->isDependentType()) 1438 return; 1439 if (FD->getResultType()->isVoidType()) 1440 ReturnsVoid = true; 1441 if (FD->hasAttr<NoReturnAttr>()) 1442 HasNoReturn = true; 1443 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1444 if (MD->getResultType()->isVoidType()) 1445 ReturnsVoid = true; 1446 if (MD->hasAttr<NoReturnAttr>()) 1447 HasNoReturn = true; 1448 } 1449 1450 // Short circuit for compilation speed. 1451 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1452 == Diagnostic::Ignored || ReturnsVoid) 1453 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1454 == Diagnostic::Ignored || !HasNoReturn) 1455 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1456 == Diagnostic::Ignored || !ReturnsVoid)) 1457 return; 1458 // FIXME: Function try block 1459 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1460 switch (CheckFallThrough(Body)) { 1461 case MaybeFallThrough: 1462 if (HasNoReturn) 1463 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1464 else if (!ReturnsVoid) 1465 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1466 break; 1467 case AlwaysFallThrough: 1468 if (HasNoReturn) 1469 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1470 else if (!ReturnsVoid) 1471 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1472 break; 1473 case NeverFallThroughOrReturn: 1474 if (ReturnsVoid && !HasNoReturn) 1475 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1476 break; 1477 case NeverFallThrough: 1478 break; 1479 } 1480 } 1481} 1482 1483/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1484/// that should return a value. Check that we don't fall off the end of a 1485/// noreturn block. We assume that functions and blocks not marked noreturn 1486/// will return. 1487void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1488 // FIXME: Would be nice if we had a better way to control cascading errors, 1489 // but for now, avoid them. The problem is that when Parse sees: 1490 // int foo() { return a; } 1491 // The return is eaten and the Sema code sees just: 1492 // int foo() { } 1493 // which this code would then warn about. 1494 if (getDiagnostics().hasErrorOccurred()) 1495 return; 1496 bool ReturnsVoid = false; 1497 bool HasNoReturn = false; 1498 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1499 if (FT->getResultType()->isVoidType()) 1500 ReturnsVoid = true; 1501 if (FT->getNoReturnAttr()) 1502 HasNoReturn = true; 1503 } 1504 1505 // Short circuit for compilation speed. 1506 if (ReturnsVoid 1507 && !HasNoReturn 1508 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1509 == Diagnostic::Ignored || !ReturnsVoid)) 1510 return; 1511 // FIXME: Funtion try block 1512 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1513 switch (CheckFallThrough(Body)) { 1514 case MaybeFallThrough: 1515 if (HasNoReturn) 1516 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1517 else if (!ReturnsVoid) 1518 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1519 break; 1520 case AlwaysFallThrough: 1521 if (HasNoReturn) 1522 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1523 else if (!ReturnsVoid) 1524 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1525 break; 1526 case NeverFallThroughOrReturn: 1527 if (ReturnsVoid) 1528 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1529 break; 1530 case NeverFallThrough: 1531 break; 1532 } 1533 } 1534} 1535 1536/// CheckParmsForFunctionDef - Check that the parameters of the given 1537/// function are appropriate for the definition of a function. This 1538/// takes care of any checks that cannot be performed on the 1539/// declaration itself, e.g., that the types of each of the function 1540/// parameters are complete. 1541bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1542 bool HasInvalidParm = false; 1543 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1544 ParmVarDecl *Param = FD->getParamDecl(p); 1545 1546 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1547 // function declarator that is part of a function definition of 1548 // that function shall not have incomplete type. 1549 // 1550 // This is also C++ [dcl.fct]p6. 1551 if (!Param->isInvalidDecl() && 1552 RequireCompleteType(Param->getLocation(), Param->getType(), 1553 diag::err_typecheck_decl_incomplete_type)) { 1554 Param->setInvalidDecl(); 1555 HasInvalidParm = true; 1556 } 1557 1558 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1559 // declaration of each parameter shall include an identifier. 1560 if (Param->getIdentifier() == 0 && 1561 !Param->isImplicit() && 1562 !getLangOptions().CPlusPlus) 1563 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1564 } 1565 1566 return HasInvalidParm; 1567} 1568 1569/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1570/// no declarator (e.g. "struct foo;") is parsed. 1571Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1572 // FIXME: Error on auto/register at file scope 1573 // FIXME: Error on inline/virtual/explicit 1574 // FIXME: Warn on useless __thread 1575 // FIXME: Warn on useless const/volatile 1576 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1577 // FIXME: Warn on useless attributes 1578 Decl *TagD = 0; 1579 TagDecl *Tag = 0; 1580 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1581 DS.getTypeSpecType() == DeclSpec::TST_struct || 1582 DS.getTypeSpecType() == DeclSpec::TST_union || 1583 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1584 TagD = static_cast<Decl *>(DS.getTypeRep()); 1585 1586 if (!TagD) // We probably had an error 1587 return DeclPtrTy(); 1588 1589 // Note that the above type specs guarantee that the 1590 // type rep is a Decl, whereas in many of the others 1591 // it's a Type. 1592 Tag = dyn_cast<TagDecl>(TagD); 1593 } 1594 1595 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1596 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1597 // or incomplete types shall not be restrict-qualified." 1598 if (TypeQuals & DeclSpec::TQ_restrict) 1599 Diag(DS.getRestrictSpecLoc(), 1600 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1601 << DS.getSourceRange(); 1602 } 1603 1604 if (DS.isFriendSpecified()) { 1605 // If we're dealing with a class template decl, assume that the 1606 // template routines are handling it. 1607 if (TagD && isa<ClassTemplateDecl>(TagD)) 1608 return DeclPtrTy(); 1609 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1610 } 1611 1612 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1613 // If there are attributes in the DeclSpec, apply them to the record. 1614 if (const AttributeList *AL = DS.getAttributes()) 1615 ProcessDeclAttributeList(S, Record, AL); 1616 1617 if (!Record->getDeclName() && Record->isDefinition() && 1618 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1619 if (getLangOptions().CPlusPlus || 1620 Record->getDeclContext()->isRecord()) 1621 return BuildAnonymousStructOrUnion(S, DS, Record); 1622 1623 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1624 << DS.getSourceRange(); 1625 } 1626 1627 // Microsoft allows unnamed struct/union fields. Don't complain 1628 // about them. 1629 // FIXME: Should we support Microsoft's extensions in this area? 1630 if (Record->getDeclName() && getLangOptions().Microsoft) 1631 return DeclPtrTy::make(Tag); 1632 } 1633 1634 if (!DS.isMissingDeclaratorOk() && 1635 DS.getTypeSpecType() != DeclSpec::TST_error) { 1636 // Warn about typedefs of enums without names, since this is an 1637 // extension in both Microsoft an GNU. 1638 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1639 Tag && isa<EnumDecl>(Tag)) { 1640 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1641 << DS.getSourceRange(); 1642 return DeclPtrTy::make(Tag); 1643 } 1644 1645 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1646 << DS.getSourceRange(); 1647 return DeclPtrTy(); 1648 } 1649 1650 return DeclPtrTy::make(Tag); 1651} 1652 1653/// We are trying to inject an anonymous member into the given scope; 1654/// check if there's an existing declaration that can't be overloaded. 1655/// 1656/// \return true if this is a forbidden redeclaration 1657static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1658 Scope *S, 1659 DeclarationName Name, 1660 SourceLocation NameLoc, 1661 unsigned diagnostic) { 1662 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1663 Sema::ForRedeclaration); 1664 if (!SemaRef.LookupName(R, S)) return false; 1665 1666 if (R.getAsSingle<TagDecl>()) 1667 return false; 1668 1669 // Pick a representative declaration. 1670 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1671 1672 SemaRef.Diag(NameLoc, diagnostic) << Name; 1673 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1674 1675 return true; 1676} 1677 1678/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1679/// anonymous struct or union AnonRecord into the owning context Owner 1680/// and scope S. This routine will be invoked just after we realize 1681/// that an unnamed union or struct is actually an anonymous union or 1682/// struct, e.g., 1683/// 1684/// @code 1685/// union { 1686/// int i; 1687/// float f; 1688/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1689/// // f into the surrounding scope.x 1690/// @endcode 1691/// 1692/// This routine is recursive, injecting the names of nested anonymous 1693/// structs/unions into the owning context and scope as well. 1694bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1695 RecordDecl *AnonRecord) { 1696 unsigned diagKind 1697 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1698 : diag::err_anonymous_struct_member_redecl; 1699 1700 bool Invalid = false; 1701 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1702 FEnd = AnonRecord->field_end(); 1703 F != FEnd; ++F) { 1704 if ((*F)->getDeclName()) { 1705 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1706 (*F)->getLocation(), diagKind)) { 1707 // C++ [class.union]p2: 1708 // The names of the members of an anonymous union shall be 1709 // distinct from the names of any other entity in the 1710 // scope in which the anonymous union is declared. 1711 Invalid = true; 1712 } else { 1713 // C++ [class.union]p2: 1714 // For the purpose of name lookup, after the anonymous union 1715 // definition, the members of the anonymous union are 1716 // considered to have been defined in the scope in which the 1717 // anonymous union is declared. 1718 Owner->makeDeclVisibleInContext(*F); 1719 S->AddDecl(DeclPtrTy::make(*F)); 1720 IdResolver.AddDecl(*F); 1721 } 1722 } else if (const RecordType *InnerRecordType 1723 = (*F)->getType()->getAs<RecordType>()) { 1724 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1725 if (InnerRecord->isAnonymousStructOrUnion()) 1726 Invalid = Invalid || 1727 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1728 } 1729 } 1730 1731 return Invalid; 1732} 1733 1734/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1735/// anonymous structure or union. Anonymous unions are a C++ feature 1736/// (C++ [class.union]) and a GNU C extension; anonymous structures 1737/// are a GNU C and GNU C++ extension. 1738Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1739 RecordDecl *Record) { 1740 DeclContext *Owner = Record->getDeclContext(); 1741 1742 // Diagnose whether this anonymous struct/union is an extension. 1743 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1744 Diag(Record->getLocation(), diag::ext_anonymous_union); 1745 else if (!Record->isUnion()) 1746 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1747 1748 // C and C++ require different kinds of checks for anonymous 1749 // structs/unions. 1750 bool Invalid = false; 1751 if (getLangOptions().CPlusPlus) { 1752 const char* PrevSpec = 0; 1753 unsigned DiagID; 1754 // C++ [class.union]p3: 1755 // Anonymous unions declared in a named namespace or in the 1756 // global namespace shall be declared static. 1757 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1758 (isa<TranslationUnitDecl>(Owner) || 1759 (isa<NamespaceDecl>(Owner) && 1760 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1761 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1762 Invalid = true; 1763 1764 // Recover by adding 'static'. 1765 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1766 PrevSpec, DiagID); 1767 } 1768 // C++ [class.union]p3: 1769 // A storage class is not allowed in a declaration of an 1770 // anonymous union in a class scope. 1771 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1772 isa<RecordDecl>(Owner)) { 1773 Diag(DS.getStorageClassSpecLoc(), 1774 diag::err_anonymous_union_with_storage_spec); 1775 Invalid = true; 1776 1777 // Recover by removing the storage specifier. 1778 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1779 PrevSpec, DiagID); 1780 } 1781 1782 // C++ [class.union]p2: 1783 // The member-specification of an anonymous union shall only 1784 // define non-static data members. [Note: nested types and 1785 // functions cannot be declared within an anonymous union. ] 1786 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1787 MemEnd = Record->decls_end(); 1788 Mem != MemEnd; ++Mem) { 1789 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1790 // C++ [class.union]p3: 1791 // An anonymous union shall not have private or protected 1792 // members (clause 11). 1793 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1794 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1795 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1796 Invalid = true; 1797 } 1798 } else if ((*Mem)->isImplicit()) { 1799 // Any implicit members are fine. 1800 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1801 // This is a type that showed up in an 1802 // elaborated-type-specifier inside the anonymous struct or 1803 // union, but which actually declares a type outside of the 1804 // anonymous struct or union. It's okay. 1805 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1806 if (!MemRecord->isAnonymousStructOrUnion() && 1807 MemRecord->getDeclName()) { 1808 // This is a nested type declaration. 1809 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1810 << (int)Record->isUnion(); 1811 Invalid = true; 1812 } 1813 } else { 1814 // We have something that isn't a non-static data 1815 // member. Complain about it. 1816 unsigned DK = diag::err_anonymous_record_bad_member; 1817 if (isa<TypeDecl>(*Mem)) 1818 DK = diag::err_anonymous_record_with_type; 1819 else if (isa<FunctionDecl>(*Mem)) 1820 DK = diag::err_anonymous_record_with_function; 1821 else if (isa<VarDecl>(*Mem)) 1822 DK = diag::err_anonymous_record_with_static; 1823 Diag((*Mem)->getLocation(), DK) 1824 << (int)Record->isUnion(); 1825 Invalid = true; 1826 } 1827 } 1828 } 1829 1830 if (!Record->isUnion() && !Owner->isRecord()) { 1831 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1832 << (int)getLangOptions().CPlusPlus; 1833 Invalid = true; 1834 } 1835 1836 // Mock up a declarator. 1837 Declarator Dc(DS, Declarator::TypeNameContext); 1838 TypeSourceInfo *TInfo = 0; 1839 GetTypeForDeclarator(Dc, S, &TInfo); 1840 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1841 1842 // Create a declaration for this anonymous struct/union. 1843 NamedDecl *Anon = 0; 1844 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1845 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1846 /*IdentifierInfo=*/0, 1847 Context.getTypeDeclType(Record), 1848 TInfo, 1849 /*BitWidth=*/0, /*Mutable=*/false); 1850 Anon->setAccess(AS_public); 1851 if (getLangOptions().CPlusPlus) 1852 FieldCollector->Add(cast<FieldDecl>(Anon)); 1853 } else { 1854 VarDecl::StorageClass SC; 1855 switch (DS.getStorageClassSpec()) { 1856 default: assert(0 && "Unknown storage class!"); 1857 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1858 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1859 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1860 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1861 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1862 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1863 case DeclSpec::SCS_mutable: 1864 // mutable can only appear on non-static class members, so it's always 1865 // an error here 1866 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1867 Invalid = true; 1868 SC = VarDecl::None; 1869 break; 1870 } 1871 1872 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1873 /*IdentifierInfo=*/0, 1874 Context.getTypeDeclType(Record), 1875 TInfo, 1876 SC); 1877 } 1878 Anon->setImplicit(); 1879 1880 // Add the anonymous struct/union object to the current 1881 // context. We'll be referencing this object when we refer to one of 1882 // its members. 1883 Owner->addDecl(Anon); 1884 1885 // Inject the members of the anonymous struct/union into the owning 1886 // context and into the identifier resolver chain for name lookup 1887 // purposes. 1888 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1889 Invalid = true; 1890 1891 // Mark this as an anonymous struct/union type. Note that we do not 1892 // do this until after we have already checked and injected the 1893 // members of this anonymous struct/union type, because otherwise 1894 // the members could be injected twice: once by DeclContext when it 1895 // builds its lookup table, and once by 1896 // InjectAnonymousStructOrUnionMembers. 1897 Record->setAnonymousStructOrUnion(true); 1898 1899 if (Invalid) 1900 Anon->setInvalidDecl(); 1901 1902 return DeclPtrTy::make(Anon); 1903} 1904 1905 1906/// GetNameForDeclarator - Determine the full declaration name for the 1907/// given Declarator. 1908DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1909 return GetNameFromUnqualifiedId(D.getName()); 1910} 1911 1912/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1913DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1914 switch (Name.getKind()) { 1915 case UnqualifiedId::IK_Identifier: 1916 return DeclarationName(Name.Identifier); 1917 1918 case UnqualifiedId::IK_OperatorFunctionId: 1919 return Context.DeclarationNames.getCXXOperatorName( 1920 Name.OperatorFunctionId.Operator); 1921 1922 case UnqualifiedId::IK_LiteralOperatorId: 1923 return Context.DeclarationNames.getCXXLiteralOperatorName( 1924 Name.Identifier); 1925 1926 case UnqualifiedId::IK_ConversionFunctionId: { 1927 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1928 if (Ty.isNull()) 1929 return DeclarationName(); 1930 1931 return Context.DeclarationNames.getCXXConversionFunctionName( 1932 Context.getCanonicalType(Ty)); 1933 } 1934 1935 case UnqualifiedId::IK_ConstructorName: { 1936 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1937 if (Ty.isNull()) 1938 return DeclarationName(); 1939 1940 return Context.DeclarationNames.getCXXConstructorName( 1941 Context.getCanonicalType(Ty)); 1942 } 1943 1944 case UnqualifiedId::IK_DestructorName: { 1945 QualType Ty = GetTypeFromParser(Name.DestructorName); 1946 if (Ty.isNull()) 1947 return DeclarationName(); 1948 1949 return Context.DeclarationNames.getCXXDestructorName( 1950 Context.getCanonicalType(Ty)); 1951 } 1952 1953 case UnqualifiedId::IK_TemplateId: { 1954 TemplateName TName 1955 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1956 return Context.getNameForTemplate(TName); 1957 } 1958 } 1959 1960 assert(false && "Unknown name kind"); 1961 return DeclarationName(); 1962} 1963 1964/// isNearlyMatchingFunction - Determine whether the C++ functions 1965/// Declaration and Definition are "nearly" matching. This heuristic 1966/// is used to improve diagnostics in the case where an out-of-line 1967/// function definition doesn't match any declaration within 1968/// the class or namespace. 1969static bool isNearlyMatchingFunction(ASTContext &Context, 1970 FunctionDecl *Declaration, 1971 FunctionDecl *Definition) { 1972 if (Declaration->param_size() != Definition->param_size()) 1973 return false; 1974 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1975 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1976 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1977 1978 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1979 DefParamTy.getNonReferenceType())) 1980 return false; 1981 } 1982 1983 return true; 1984} 1985 1986Sema::DeclPtrTy 1987Sema::HandleDeclarator(Scope *S, Declarator &D, 1988 MultiTemplateParamsArg TemplateParamLists, 1989 bool IsFunctionDefinition) { 1990 DeclarationName Name = GetNameForDeclarator(D); 1991 1992 // All of these full declarators require an identifier. If it doesn't have 1993 // one, the ParsedFreeStandingDeclSpec action should be used. 1994 if (!Name) { 1995 if (!D.isInvalidType()) // Reject this if we think it is valid. 1996 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1997 diag::err_declarator_need_ident) 1998 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1999 return DeclPtrTy(); 2000 } 2001 2002 // The scope passed in may not be a decl scope. Zip up the scope tree until 2003 // we find one that is. 2004 while ((S->getFlags() & Scope::DeclScope) == 0 || 2005 (S->getFlags() & Scope::TemplateParamScope) != 0) 2006 S = S->getParent(); 2007 2008 // If this is an out-of-line definition of a member of a class template 2009 // or class template partial specialization, we may need to rebuild the 2010 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 2011 // for more information. 2012 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 2013 // handle expressions properly. 2014 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 2015 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 2016 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 2017 (DS.getTypeSpecType() == DeclSpec::TST_typename || 2018 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 2019 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 2020 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 2021 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 2022 // FIXME: Preserve type source info. 2023 QualType T = GetTypeFromParser(DS.getTypeRep()); 2024 2025 DeclContext *SavedContext = CurContext; 2026 CurContext = DC; 2027 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 2028 CurContext = SavedContext; 2029 2030 if (T.isNull()) 2031 return DeclPtrTy(); 2032 DS.UpdateTypeRep(T.getAsOpaquePtr()); 2033 } 2034 } 2035 2036 DeclContext *DC; 2037 NamedDecl *New; 2038 2039 TypeSourceInfo *TInfo = 0; 2040 QualType R = GetTypeForDeclarator(D, S, &TInfo); 2041 2042 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2043 ForRedeclaration); 2044 2045 // See if this is a redefinition of a variable in the same scope. 2046 if (D.getCXXScopeSpec().isInvalid()) { 2047 DC = CurContext; 2048 D.setInvalidType(); 2049 } else if (!D.getCXXScopeSpec().isSet()) { 2050 bool IsLinkageLookup = false; 2051 2052 // If the declaration we're planning to build will be a function 2053 // or object with linkage, then look for another declaration with 2054 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2055 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2056 /* Do nothing*/; 2057 else if (R->isFunctionType()) { 2058 if (CurContext->isFunctionOrMethod() || 2059 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2060 IsLinkageLookup = true; 2061 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2062 IsLinkageLookup = true; 2063 else if (CurContext->getLookupContext()->isTranslationUnit() && 2064 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2065 IsLinkageLookup = true; 2066 2067 if (IsLinkageLookup) 2068 Previous.clear(LookupRedeclarationWithLinkage); 2069 2070 DC = CurContext; 2071 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2072 } else { // Something like "int foo::x;" 2073 DC = computeDeclContext(D.getCXXScopeSpec(), true); 2074 2075 if (!DC) { 2076 // If we could not compute the declaration context, it's because the 2077 // declaration context is dependent but does not refer to a class, 2078 // class template, or class template partial specialization. Complain 2079 // and return early, to avoid the coming semantic disaster. 2080 Diag(D.getIdentifierLoc(), 2081 diag::err_template_qualified_declarator_no_match) 2082 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2083 << D.getCXXScopeSpec().getRange(); 2084 return DeclPtrTy(); 2085 } 2086 2087 if (!DC->isDependentContext() && 2088 RequireCompleteDeclContext(D.getCXXScopeSpec())) 2089 return DeclPtrTy(); 2090 2091 LookupQualifiedName(Previous, DC); 2092 2093 // Don't consider using declarations as previous declarations for 2094 // out-of-line members. 2095 RemoveUsingDecls(Previous); 2096 2097 // C++ 7.3.1.2p2: 2098 // Members (including explicit specializations of templates) of a named 2099 // namespace can also be defined outside that namespace by explicit 2100 // qualification of the name being defined, provided that the entity being 2101 // defined was already declared in the namespace and the definition appears 2102 // after the point of declaration in a namespace that encloses the 2103 // declarations namespace. 2104 // 2105 // Note that we only check the context at this point. We don't yet 2106 // have enough information to make sure that PrevDecl is actually 2107 // the declaration we want to match. For example, given: 2108 // 2109 // class X { 2110 // void f(); 2111 // void f(float); 2112 // }; 2113 // 2114 // void X::f(int) { } // ill-formed 2115 // 2116 // In this case, PrevDecl will point to the overload set 2117 // containing the two f's declared in X, but neither of them 2118 // matches. 2119 2120 // First check whether we named the global scope. 2121 if (isa<TranslationUnitDecl>(DC)) { 2122 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2123 << Name << D.getCXXScopeSpec().getRange(); 2124 } else { 2125 DeclContext *Cur = CurContext; 2126 while (isa<LinkageSpecDecl>(Cur)) 2127 Cur = Cur->getParent(); 2128 if (!Cur->Encloses(DC)) { 2129 // The qualifying scope doesn't enclose the original declaration. 2130 // Emit diagnostic based on current scope. 2131 SourceLocation L = D.getIdentifierLoc(); 2132 SourceRange R = D.getCXXScopeSpec().getRange(); 2133 if (isa<FunctionDecl>(Cur)) 2134 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2135 else 2136 Diag(L, diag::err_invalid_declarator_scope) 2137 << Name << cast<NamedDecl>(DC) << R; 2138 D.setInvalidType(); 2139 } 2140 } 2141 } 2142 2143 if (Previous.isSingleResult() && 2144 Previous.getFoundDecl()->isTemplateParameter()) { 2145 // Maybe we will complain about the shadowed template parameter. 2146 if (!D.isInvalidType()) 2147 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2148 Previous.getFoundDecl())) 2149 D.setInvalidType(); 2150 2151 // Just pretend that we didn't see the previous declaration. 2152 Previous.clear(); 2153 } 2154 2155 // In C++, the previous declaration we find might be a tag type 2156 // (class or enum). In this case, the new declaration will hide the 2157 // tag type. Note that this does does not apply if we're declaring a 2158 // typedef (C++ [dcl.typedef]p4). 2159 if (Previous.isSingleTagDecl() && 2160 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2161 Previous.clear(); 2162 2163 bool Redeclaration = false; 2164 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2165 if (TemplateParamLists.size()) { 2166 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2167 return DeclPtrTy(); 2168 } 2169 2170 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2171 } else if (R->isFunctionType()) { 2172 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2173 move(TemplateParamLists), 2174 IsFunctionDefinition, Redeclaration); 2175 } else { 2176 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2177 move(TemplateParamLists), 2178 Redeclaration); 2179 } 2180 2181 if (New == 0) 2182 return DeclPtrTy(); 2183 2184 // If this has an identifier and is not an invalid redeclaration or 2185 // function template specialization, add it to the scope stack. 2186 if (Name && !(Redeclaration && New->isInvalidDecl())) 2187 PushOnScopeChains(New, S); 2188 2189 return DeclPtrTy::make(New); 2190} 2191 2192/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2193/// types into constant array types in certain situations which would otherwise 2194/// be errors (for GCC compatibility). 2195static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2196 ASTContext &Context, 2197 bool &SizeIsNegative) { 2198 // This method tries to turn a variable array into a constant 2199 // array even when the size isn't an ICE. This is necessary 2200 // for compatibility with code that depends on gcc's buggy 2201 // constant expression folding, like struct {char x[(int)(char*)2];} 2202 SizeIsNegative = false; 2203 2204 QualifierCollector Qs; 2205 const Type *Ty = Qs.strip(T); 2206 2207 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2208 QualType Pointee = PTy->getPointeeType(); 2209 QualType FixedType = 2210 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2211 if (FixedType.isNull()) return FixedType; 2212 FixedType = Context.getPointerType(FixedType); 2213 return Qs.apply(FixedType); 2214 } 2215 2216 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2217 if (!VLATy) 2218 return QualType(); 2219 // FIXME: We should probably handle this case 2220 if (VLATy->getElementType()->isVariablyModifiedType()) 2221 return QualType(); 2222 2223 Expr::EvalResult EvalResult; 2224 if (!VLATy->getSizeExpr() || 2225 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2226 !EvalResult.Val.isInt()) 2227 return QualType(); 2228 2229 llvm::APSInt &Res = EvalResult.Val.getInt(); 2230 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2231 // TODO: preserve the size expression in declarator info 2232 return Context.getConstantArrayType(VLATy->getElementType(), 2233 Res, ArrayType::Normal, 0); 2234 } 2235 2236 SizeIsNegative = true; 2237 return QualType(); 2238} 2239 2240/// \brief Register the given locally-scoped external C declaration so 2241/// that it can be found later for redeclarations 2242void 2243Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2244 const LookupResult &Previous, 2245 Scope *S) { 2246 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2247 "Decl is not a locally-scoped decl!"); 2248 // Note that we have a locally-scoped external with this name. 2249 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2250 2251 if (!Previous.isSingleResult()) 2252 return; 2253 2254 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2255 2256 // If there was a previous declaration of this variable, it may be 2257 // in our identifier chain. Update the identifier chain with the new 2258 // declaration. 2259 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2260 // The previous declaration was found on the identifer resolver 2261 // chain, so remove it from its scope. 2262 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2263 S = S->getParent(); 2264 2265 if (S) 2266 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2267 } 2268} 2269 2270/// \brief Diagnose function specifiers on a declaration of an identifier that 2271/// does not identify a function. 2272void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2273 // FIXME: We should probably indicate the identifier in question to avoid 2274 // confusion for constructs like "inline int a(), b;" 2275 if (D.getDeclSpec().isInlineSpecified()) 2276 Diag(D.getDeclSpec().getInlineSpecLoc(), 2277 diag::err_inline_non_function); 2278 2279 if (D.getDeclSpec().isVirtualSpecified()) 2280 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2281 diag::err_virtual_non_function); 2282 2283 if (D.getDeclSpec().isExplicitSpecified()) 2284 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2285 diag::err_explicit_non_function); 2286} 2287 2288NamedDecl* 2289Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2290 QualType R, TypeSourceInfo *TInfo, 2291 LookupResult &Previous, bool &Redeclaration) { 2292 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2293 if (D.getCXXScopeSpec().isSet()) { 2294 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2295 << D.getCXXScopeSpec().getRange(); 2296 D.setInvalidType(); 2297 // Pretend we didn't see the scope specifier. 2298 DC = 0; 2299 } 2300 2301 if (getLangOptions().CPlusPlus) { 2302 // Check that there are no default arguments (C++ only). 2303 CheckExtraCXXDefaultArguments(D); 2304 } 2305 2306 DiagnoseFunctionSpecifiers(D); 2307 2308 if (D.getDeclSpec().isThreadSpecified()) 2309 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2310 2311 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2312 if (!NewTD) return 0; 2313 2314 // Handle attributes prior to checking for duplicates in MergeVarDecl 2315 ProcessDeclAttributes(S, NewTD, D); 2316 2317 // Merge the decl with the existing one if appropriate. If the decl is 2318 // in an outer scope, it isn't the same thing. 2319 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2320 if (!Previous.empty()) { 2321 Redeclaration = true; 2322 MergeTypeDefDecl(NewTD, Previous); 2323 } 2324 2325 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2326 // then it shall have block scope. 2327 QualType T = NewTD->getUnderlyingType(); 2328 if (T->isVariablyModifiedType()) { 2329 CurFunctionNeedsScopeChecking = true; 2330 2331 if (S->getFnParent() == 0) { 2332 bool SizeIsNegative; 2333 QualType FixedTy = 2334 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2335 if (!FixedTy.isNull()) { 2336 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2337 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2338 } else { 2339 if (SizeIsNegative) 2340 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2341 else if (T->isVariableArrayType()) 2342 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2343 else 2344 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2345 NewTD->setInvalidDecl(); 2346 } 2347 } 2348 } 2349 2350 // If this is the C FILE type, notify the AST context. 2351 if (IdentifierInfo *II = NewTD->getIdentifier()) 2352 if (!NewTD->isInvalidDecl() && 2353 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2354 if (II->isStr("FILE")) 2355 Context.setFILEDecl(NewTD); 2356 else if (II->isStr("jmp_buf")) 2357 Context.setjmp_bufDecl(NewTD); 2358 else if (II->isStr("sigjmp_buf")) 2359 Context.setsigjmp_bufDecl(NewTD); 2360 } 2361 2362 return NewTD; 2363} 2364 2365/// \brief Determines whether the given declaration is an out-of-scope 2366/// previous declaration. 2367/// 2368/// This routine should be invoked when name lookup has found a 2369/// previous declaration (PrevDecl) that is not in the scope where a 2370/// new declaration by the same name is being introduced. If the new 2371/// declaration occurs in a local scope, previous declarations with 2372/// linkage may still be considered previous declarations (C99 2373/// 6.2.2p4-5, C++ [basic.link]p6). 2374/// 2375/// \param PrevDecl the previous declaration found by name 2376/// lookup 2377/// 2378/// \param DC the context in which the new declaration is being 2379/// declared. 2380/// 2381/// \returns true if PrevDecl is an out-of-scope previous declaration 2382/// for a new delcaration with the same name. 2383static bool 2384isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2385 ASTContext &Context) { 2386 if (!PrevDecl) 2387 return 0; 2388 2389 if (!PrevDecl->hasLinkage()) 2390 return false; 2391 2392 if (Context.getLangOptions().CPlusPlus) { 2393 // C++ [basic.link]p6: 2394 // If there is a visible declaration of an entity with linkage 2395 // having the same name and type, ignoring entities declared 2396 // outside the innermost enclosing namespace scope, the block 2397 // scope declaration declares that same entity and receives the 2398 // linkage of the previous declaration. 2399 DeclContext *OuterContext = DC->getLookupContext(); 2400 if (!OuterContext->isFunctionOrMethod()) 2401 // This rule only applies to block-scope declarations. 2402 return false; 2403 else { 2404 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2405 if (PrevOuterContext->isRecord()) 2406 // We found a member function: ignore it. 2407 return false; 2408 else { 2409 // Find the innermost enclosing namespace for the new and 2410 // previous declarations. 2411 while (!OuterContext->isFileContext()) 2412 OuterContext = OuterContext->getParent(); 2413 while (!PrevOuterContext->isFileContext()) 2414 PrevOuterContext = PrevOuterContext->getParent(); 2415 2416 // The previous declaration is in a different namespace, so it 2417 // isn't the same function. 2418 if (OuterContext->getPrimaryContext() != 2419 PrevOuterContext->getPrimaryContext()) 2420 return false; 2421 } 2422 } 2423 } 2424 2425 return true; 2426} 2427 2428NamedDecl* 2429Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2430 QualType R, TypeSourceInfo *TInfo, 2431 LookupResult &Previous, 2432 MultiTemplateParamsArg TemplateParamLists, 2433 bool &Redeclaration) { 2434 DeclarationName Name = GetNameForDeclarator(D); 2435 2436 // Check that there are no default arguments (C++ only). 2437 if (getLangOptions().CPlusPlus) 2438 CheckExtraCXXDefaultArguments(D); 2439 2440 VarDecl *NewVD; 2441 VarDecl::StorageClass SC; 2442 switch (D.getDeclSpec().getStorageClassSpec()) { 2443 default: assert(0 && "Unknown storage class!"); 2444 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2445 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2446 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2447 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2448 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2449 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2450 case DeclSpec::SCS_mutable: 2451 // mutable can only appear on non-static class members, so it's always 2452 // an error here 2453 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2454 D.setInvalidType(); 2455 SC = VarDecl::None; 2456 break; 2457 } 2458 2459 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2460 if (!II) { 2461 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2462 << Name.getAsString(); 2463 return 0; 2464 } 2465 2466 DiagnoseFunctionSpecifiers(D); 2467 2468 if (!DC->isRecord() && S->getFnParent() == 0) { 2469 // C99 6.9p2: The storage-class specifiers auto and register shall not 2470 // appear in the declaration specifiers in an external declaration. 2471 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2472 2473 // If this is a register variable with an asm label specified, then this 2474 // is a GNU extension. 2475 if (SC == VarDecl::Register && D.getAsmLabel()) 2476 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2477 else 2478 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2479 D.setInvalidType(); 2480 } 2481 } 2482 if (DC->isRecord() && !CurContext->isRecord()) { 2483 // This is an out-of-line definition of a static data member. 2484 if (SC == VarDecl::Static) { 2485 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2486 diag::err_static_out_of_line) 2487 << CodeModificationHint::CreateRemoval( 2488 D.getDeclSpec().getStorageClassSpecLoc()); 2489 } else if (SC == VarDecl::None) 2490 SC = VarDecl::Static; 2491 } 2492 if (SC == VarDecl::Static) { 2493 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2494 if (RD->isLocalClass()) 2495 Diag(D.getIdentifierLoc(), 2496 diag::err_static_data_member_not_allowed_in_local_class) 2497 << Name << RD->getDeclName(); 2498 } 2499 } 2500 2501 // Match up the template parameter lists with the scope specifier, then 2502 // determine whether we have a template or a template specialization. 2503 bool isExplicitSpecialization = false; 2504 if (TemplateParameterList *TemplateParams 2505 = MatchTemplateParametersToScopeSpecifier( 2506 D.getDeclSpec().getSourceRange().getBegin(), 2507 D.getCXXScopeSpec(), 2508 (TemplateParameterList**)TemplateParamLists.get(), 2509 TemplateParamLists.size(), 2510 isExplicitSpecialization)) { 2511 if (TemplateParams->size() > 0) { 2512 // There is no such thing as a variable template. 2513 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2514 << II 2515 << SourceRange(TemplateParams->getTemplateLoc(), 2516 TemplateParams->getRAngleLoc()); 2517 return 0; 2518 } else { 2519 // There is an extraneous 'template<>' for this variable. Complain 2520 // about it, but allow the declaration of the variable. 2521 Diag(TemplateParams->getTemplateLoc(), 2522 diag::err_template_variable_noparams) 2523 << II 2524 << SourceRange(TemplateParams->getTemplateLoc(), 2525 TemplateParams->getRAngleLoc()); 2526 2527 isExplicitSpecialization = true; 2528 } 2529 } 2530 2531 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2532 II, R, TInfo, SC); 2533 2534 if (D.isInvalidType()) 2535 NewVD->setInvalidDecl(); 2536 2537 if (D.getDeclSpec().isThreadSpecified()) { 2538 if (NewVD->hasLocalStorage()) 2539 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2540 else if (!Context.Target.isTLSSupported()) 2541 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2542 else 2543 NewVD->setThreadSpecified(true); 2544 } 2545 2546 // Set the lexical context. If the declarator has a C++ scope specifier, the 2547 // lexical context will be different from the semantic context. 2548 NewVD->setLexicalDeclContext(CurContext); 2549 2550 // Handle attributes prior to checking for duplicates in MergeVarDecl 2551 ProcessDeclAttributes(S, NewVD, D); 2552 2553 // Handle GNU asm-label extension (encoded as an attribute). 2554 if (Expr *E = (Expr*) D.getAsmLabel()) { 2555 // The parser guarantees this is a string. 2556 StringLiteral *SE = cast<StringLiteral>(E); 2557 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2558 } 2559 2560 // Don't consider existing declarations that are in a different 2561 // scope and are out-of-semantic-context declarations (if the new 2562 // declaration has linkage). 2563 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2564 2565 // Merge the decl with the existing one if appropriate. 2566 if (!Previous.empty()) { 2567 if (Previous.isSingleResult() && 2568 isa<FieldDecl>(Previous.getFoundDecl()) && 2569 D.getCXXScopeSpec().isSet()) { 2570 // The user tried to define a non-static data member 2571 // out-of-line (C++ [dcl.meaning]p1). 2572 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2573 << D.getCXXScopeSpec().getRange(); 2574 Previous.clear(); 2575 NewVD->setInvalidDecl(); 2576 } 2577 } else if (D.getCXXScopeSpec().isSet()) { 2578 // No previous declaration in the qualifying scope. 2579 Diag(D.getIdentifierLoc(), diag::err_no_member) 2580 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2581 << D.getCXXScopeSpec().getRange(); 2582 NewVD->setInvalidDecl(); 2583 } 2584 2585 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2586 2587 // This is an explicit specialization of a static data member. Check it. 2588 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2589 CheckMemberSpecialization(NewVD, Previous)) 2590 NewVD->setInvalidDecl(); 2591 2592 // attributes declared post-definition are currently ignored 2593 if (Previous.isSingleResult()) { 2594 const VarDecl *Def = 0; 2595 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2596 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2597 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2598 Diag(Def->getLocation(), diag::note_previous_definition); 2599 } 2600 } 2601 2602 // If this is a locally-scoped extern C variable, update the map of 2603 // such variables. 2604 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2605 !NewVD->isInvalidDecl()) 2606 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2607 2608 return NewVD; 2609} 2610 2611/// \brief Perform semantic checking on a newly-created variable 2612/// declaration. 2613/// 2614/// This routine performs all of the type-checking required for a 2615/// variable declaration once it has been built. It is used both to 2616/// check variables after they have been parsed and their declarators 2617/// have been translated into a declaration, and to check variables 2618/// that have been instantiated from a template. 2619/// 2620/// Sets NewVD->isInvalidDecl() if an error was encountered. 2621void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2622 LookupResult &Previous, 2623 bool &Redeclaration) { 2624 // If the decl is already known invalid, don't check it. 2625 if (NewVD->isInvalidDecl()) 2626 return; 2627 2628 QualType T = NewVD->getType(); 2629 2630 if (T->isObjCInterfaceType()) { 2631 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2632 return NewVD->setInvalidDecl(); 2633 } 2634 2635 // Emit an error if an address space was applied to decl with local storage. 2636 // This includes arrays of objects with address space qualifiers, but not 2637 // automatic variables that point to other address spaces. 2638 // ISO/IEC TR 18037 S5.1.2 2639 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2640 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2641 return NewVD->setInvalidDecl(); 2642 } 2643 2644 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2645 && !NewVD->hasAttr<BlocksAttr>()) 2646 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2647 2648 bool isVM = T->isVariablyModifiedType(); 2649 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2650 NewVD->hasAttr<BlocksAttr>()) 2651 CurFunctionNeedsScopeChecking = true; 2652 2653 if ((isVM && NewVD->hasLinkage()) || 2654 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2655 bool SizeIsNegative; 2656 QualType FixedTy = 2657 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2658 2659 if (FixedTy.isNull() && T->isVariableArrayType()) { 2660 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2661 // FIXME: This won't give the correct result for 2662 // int a[10][n]; 2663 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2664 2665 if (NewVD->isFileVarDecl()) 2666 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2667 << SizeRange; 2668 else if (NewVD->getStorageClass() == VarDecl::Static) 2669 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2670 << SizeRange; 2671 else 2672 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2673 << SizeRange; 2674 return NewVD->setInvalidDecl(); 2675 } 2676 2677 if (FixedTy.isNull()) { 2678 if (NewVD->isFileVarDecl()) 2679 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2680 else 2681 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2682 return NewVD->setInvalidDecl(); 2683 } 2684 2685 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2686 NewVD->setType(FixedTy); 2687 } 2688 2689 if (Previous.empty() && NewVD->isExternC()) { 2690 // Since we did not find anything by this name and we're declaring 2691 // an extern "C" variable, look for a non-visible extern "C" 2692 // declaration with the same name. 2693 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2694 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2695 if (Pos != LocallyScopedExternalDecls.end()) 2696 Previous.addDecl(Pos->second); 2697 } 2698 2699 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2700 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2701 << T; 2702 return NewVD->setInvalidDecl(); 2703 } 2704 2705 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2706 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2707 return NewVD->setInvalidDecl(); 2708 } 2709 2710 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2711 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2712 return NewVD->setInvalidDecl(); 2713 } 2714 2715 if (!Previous.empty()) { 2716 Redeclaration = true; 2717 MergeVarDecl(NewVD, Previous); 2718 } 2719} 2720 2721/// \brief Data used with FindOverriddenMethod 2722struct FindOverriddenMethodData { 2723 Sema *S; 2724 CXXMethodDecl *Method; 2725}; 2726 2727/// \brief Member lookup function that determines whether a given C++ 2728/// method overrides a method in a base class, to be used with 2729/// CXXRecordDecl::lookupInBases(). 2730static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2731 CXXBasePath &Path, 2732 void *UserData) { 2733 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2734 2735 FindOverriddenMethodData *Data 2736 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2737 2738 DeclarationName Name = Data->Method->getDeclName(); 2739 2740 // FIXME: Do we care about other names here too? 2741 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2742 // We really want to find the base class constructor here. 2743 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2744 CanQualType CT = Data->S->Context.getCanonicalType(T); 2745 2746 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2747 } 2748 2749 for (Path.Decls = BaseRecord->lookup(Name); 2750 Path.Decls.first != Path.Decls.second; 2751 ++Path.Decls.first) { 2752 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2753 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2754 return true; 2755 } 2756 } 2757 2758 return false; 2759} 2760 2761/// AddOverriddenMethods - See if a method overrides any in the base classes, 2762/// and if so, check that it's a valid override and remember it. 2763void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2764 // Look for virtual methods in base classes that this method might override. 2765 CXXBasePaths Paths; 2766 FindOverriddenMethodData Data; 2767 Data.Method = MD; 2768 Data.S = this; 2769 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2770 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2771 E = Paths.found_decls_end(); I != E; ++I) { 2772 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2773 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2774 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2775 !CheckOverridingFunctionAttributes(MD, OldMD)) 2776 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2777 } 2778 } 2779 } 2780} 2781 2782NamedDecl* 2783Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2784 QualType R, TypeSourceInfo *TInfo, 2785 LookupResult &Previous, 2786 MultiTemplateParamsArg TemplateParamLists, 2787 bool IsFunctionDefinition, bool &Redeclaration) { 2788 assert(R.getTypePtr()->isFunctionType()); 2789 2790 DeclarationName Name = GetNameForDeclarator(D); 2791 FunctionDecl::StorageClass SC = FunctionDecl::None; 2792 switch (D.getDeclSpec().getStorageClassSpec()) { 2793 default: assert(0 && "Unknown storage class!"); 2794 case DeclSpec::SCS_auto: 2795 case DeclSpec::SCS_register: 2796 case DeclSpec::SCS_mutable: 2797 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2798 diag::err_typecheck_sclass_func); 2799 D.setInvalidType(); 2800 break; 2801 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2802 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2803 case DeclSpec::SCS_static: { 2804 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2805 // C99 6.7.1p5: 2806 // The declaration of an identifier for a function that has 2807 // block scope shall have no explicit storage-class specifier 2808 // other than extern 2809 // See also (C++ [dcl.stc]p4). 2810 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2811 diag::err_static_block_func); 2812 SC = FunctionDecl::None; 2813 } else 2814 SC = FunctionDecl::Static; 2815 break; 2816 } 2817 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2818 } 2819 2820 if (D.getDeclSpec().isThreadSpecified()) 2821 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2822 2823 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2824 bool isInline = D.getDeclSpec().isInlineSpecified(); 2825 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2826 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2827 2828 // Check that the return type is not an abstract class type. 2829 // For record types, this is done by the AbstractClassUsageDiagnoser once 2830 // the class has been completely parsed. 2831 if (!DC->isRecord() && 2832 RequireNonAbstractType(D.getIdentifierLoc(), 2833 R->getAs<FunctionType>()->getResultType(), 2834 diag::err_abstract_type_in_decl, 2835 AbstractReturnType)) 2836 D.setInvalidType(); 2837 2838 // Do not allow returning a objc interface by-value. 2839 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2840 Diag(D.getIdentifierLoc(), 2841 diag::err_object_cannot_be_passed_returned_by_value) << 0 2842 << R->getAs<FunctionType>()->getResultType(); 2843 D.setInvalidType(); 2844 } 2845 2846 bool isVirtualOkay = false; 2847 FunctionDecl *NewFD; 2848 2849 if (isFriend) { 2850 // C++ [class.friend]p5 2851 // A function can be defined in a friend declaration of a 2852 // class . . . . Such a function is implicitly inline. 2853 isInline |= IsFunctionDefinition; 2854 } 2855 2856 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2857 // This is a C++ constructor declaration. 2858 assert(DC->isRecord() && 2859 "Constructors can only be declared in a member context"); 2860 2861 R = CheckConstructorDeclarator(D, R, SC); 2862 2863 // Create the new declaration 2864 NewFD = CXXConstructorDecl::Create(Context, 2865 cast<CXXRecordDecl>(DC), 2866 D.getIdentifierLoc(), Name, R, TInfo, 2867 isExplicit, isInline, 2868 /*isImplicitlyDeclared=*/false); 2869 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2870 // This is a C++ destructor declaration. 2871 if (DC->isRecord()) { 2872 R = CheckDestructorDeclarator(D, SC); 2873 2874 NewFD = CXXDestructorDecl::Create(Context, 2875 cast<CXXRecordDecl>(DC), 2876 D.getIdentifierLoc(), Name, R, 2877 isInline, 2878 /*isImplicitlyDeclared=*/false); 2879 2880 isVirtualOkay = true; 2881 } else { 2882 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2883 2884 // Create a FunctionDecl to satisfy the function definition parsing 2885 // code path. 2886 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2887 Name, R, TInfo, SC, isInline, 2888 /*hasPrototype=*/true); 2889 D.setInvalidType(); 2890 } 2891 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2892 if (!DC->isRecord()) { 2893 Diag(D.getIdentifierLoc(), 2894 diag::err_conv_function_not_member); 2895 return 0; 2896 } 2897 2898 CheckConversionDeclarator(D, R, SC); 2899 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2900 D.getIdentifierLoc(), Name, R, TInfo, 2901 isInline, isExplicit); 2902 2903 isVirtualOkay = true; 2904 } else if (DC->isRecord()) { 2905 // If the of the function is the same as the name of the record, then this 2906 // must be an invalid constructor that has a return type. 2907 // (The parser checks for a return type and makes the declarator a 2908 // constructor if it has no return type). 2909 // must have an invalid constructor that has a return type 2910 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2911 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2912 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2913 << SourceRange(D.getIdentifierLoc()); 2914 return 0; 2915 } 2916 2917 bool isStatic = SC == FunctionDecl::Static; 2918 2919 // [class.free]p1: 2920 // Any allocation function for a class T is a static member 2921 // (even if not explicitly declared static). 2922 if (Name.getCXXOverloadedOperator() == OO_New || 2923 Name.getCXXOverloadedOperator() == OO_Array_New) 2924 isStatic = true; 2925 2926 // [class.free]p6 Any deallocation function for a class X is a static member 2927 // (even if not explicitly declared static). 2928 if (Name.getCXXOverloadedOperator() == OO_Delete || 2929 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2930 isStatic = true; 2931 2932 // This is a C++ method declaration. 2933 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2934 D.getIdentifierLoc(), Name, R, TInfo, 2935 isStatic, isInline); 2936 2937 isVirtualOkay = !isStatic; 2938 } else { 2939 // Determine whether the function was written with a 2940 // prototype. This true when: 2941 // - we're in C++ (where every function has a prototype), 2942 // - there is a prototype in the declarator, or 2943 // - the type R of the function is some kind of typedef or other reference 2944 // to a type name (which eventually refers to a function type). 2945 bool HasPrototype = 2946 getLangOptions().CPlusPlus || 2947 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2948 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2949 2950 NewFD = FunctionDecl::Create(Context, DC, 2951 D.getIdentifierLoc(), 2952 Name, R, TInfo, SC, isInline, HasPrototype); 2953 } 2954 2955 if (D.isInvalidType()) 2956 NewFD->setInvalidDecl(); 2957 2958 // Set the lexical context. If the declarator has a C++ 2959 // scope specifier, or is the object of a friend declaration, the 2960 // lexical context will be different from the semantic context. 2961 NewFD->setLexicalDeclContext(CurContext); 2962 2963 // Match up the template parameter lists with the scope specifier, then 2964 // determine whether we have a template or a template specialization. 2965 FunctionTemplateDecl *FunctionTemplate = 0; 2966 bool isExplicitSpecialization = false; 2967 bool isFunctionTemplateSpecialization = false; 2968 if (TemplateParameterList *TemplateParams 2969 = MatchTemplateParametersToScopeSpecifier( 2970 D.getDeclSpec().getSourceRange().getBegin(), 2971 D.getCXXScopeSpec(), 2972 (TemplateParameterList**)TemplateParamLists.get(), 2973 TemplateParamLists.size(), 2974 isExplicitSpecialization)) { 2975 if (TemplateParams->size() > 0) { 2976 // This is a function template 2977 2978 // Check that we can declare a template here. 2979 if (CheckTemplateDeclScope(S, TemplateParams)) 2980 return 0; 2981 2982 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2983 NewFD->getLocation(), 2984 Name, TemplateParams, 2985 NewFD); 2986 FunctionTemplate->setLexicalDeclContext(CurContext); 2987 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2988 } else { 2989 // This is a function template specialization. 2990 isFunctionTemplateSpecialization = true; 2991 } 2992 2993 // FIXME: Free this memory properly. 2994 TemplateParamLists.release(); 2995 } 2996 2997 // C++ [dcl.fct.spec]p5: 2998 // The virtual specifier shall only be used in declarations of 2999 // nonstatic class member functions that appear within a 3000 // member-specification of a class declaration; see 10.3. 3001 // 3002 if (isVirtual && !NewFD->isInvalidDecl()) { 3003 if (!isVirtualOkay) { 3004 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3005 diag::err_virtual_non_function); 3006 } else if (!CurContext->isRecord()) { 3007 // 'virtual' was specified outside of the class. 3008 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3009 << CodeModificationHint::CreateRemoval( 3010 D.getDeclSpec().getVirtualSpecLoc()); 3011 } else { 3012 // Okay: Add virtual to the method. 3013 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3014 CurClass->setMethodAsVirtual(NewFD); 3015 } 3016 } 3017 3018 // Filter out previous declarations that don't match the scope. 3019 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3020 3021 if (isFriend) { 3022 // DC is the namespace in which the function is being declared. 3023 assert((DC->isFileContext() || !Previous.empty()) && 3024 "previously-undeclared friend function being created " 3025 "in a non-namespace context"); 3026 3027 if (FunctionTemplate) { 3028 FunctionTemplate->setObjectOfFriendDecl( 3029 /* PreviouslyDeclared= */ !Previous.empty()); 3030 FunctionTemplate->setAccess(AS_public); 3031 } 3032 else 3033 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 3034 3035 NewFD->setAccess(AS_public); 3036 } 3037 3038 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3039 !CurContext->isRecord()) { 3040 // C++ [class.static]p1: 3041 // A data or function member of a class may be declared static 3042 // in a class definition, in which case it is a static member of 3043 // the class. 3044 3045 // Complain about the 'static' specifier if it's on an out-of-line 3046 // member function definition. 3047 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3048 diag::err_static_out_of_line) 3049 << CodeModificationHint::CreateRemoval( 3050 D.getDeclSpec().getStorageClassSpecLoc()); 3051 } 3052 3053 // Handle GNU asm-label extension (encoded as an attribute). 3054 if (Expr *E = (Expr*) D.getAsmLabel()) { 3055 // The parser guarantees this is a string. 3056 StringLiteral *SE = cast<StringLiteral>(E); 3057 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 3058 } 3059 3060 // Copy the parameter declarations from the declarator D to the function 3061 // declaration NewFD, if they are available. First scavenge them into Params. 3062 llvm::SmallVector<ParmVarDecl*, 16> Params; 3063 if (D.getNumTypeObjects() > 0) { 3064 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3065 3066 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3067 // function that takes no arguments, not a function that takes a 3068 // single void argument. 3069 // We let through "const void" here because Sema::GetTypeForDeclarator 3070 // already checks for that case. 3071 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3072 FTI.ArgInfo[0].Param && 3073 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3074 // Empty arg list, don't push any params. 3075 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3076 3077 // In C++, the empty parameter-type-list must be spelled "void"; a 3078 // typedef of void is not permitted. 3079 if (getLangOptions().CPlusPlus && 3080 Param->getType().getUnqualifiedType() != Context.VoidTy) 3081 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3082 // FIXME: Leaks decl? 3083 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3084 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3085 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3086 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3087 Param->setDeclContext(NewFD); 3088 Params.push_back(Param); 3089 } 3090 } 3091 3092 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3093 // When we're declaring a function with a typedef, typeof, etc as in the 3094 // following example, we'll need to synthesize (unnamed) 3095 // parameters for use in the declaration. 3096 // 3097 // @code 3098 // typedef void fn(int); 3099 // fn f; 3100 // @endcode 3101 3102 // Synthesize a parameter for each argument type. 3103 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3104 AE = FT->arg_type_end(); AI != AE; ++AI) { 3105 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 3106 SourceLocation(), 0, 3107 *AI, /*TInfo=*/0, 3108 VarDecl::None, 0); 3109 Param->setImplicit(); 3110 Params.push_back(Param); 3111 } 3112 } else { 3113 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3114 "Should not need args for typedef of non-prototype fn"); 3115 } 3116 // Finally, we know we have the right number of parameters, install them. 3117 NewFD->setParams(Context, Params.data(), Params.size()); 3118 3119 // If the declarator is a template-id, translate the parser's template 3120 // argument list into our AST format. 3121 bool HasExplicitTemplateArgs = false; 3122 TemplateArgumentListInfo TemplateArgs; 3123 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3124 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3125 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3126 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3127 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3128 TemplateId->getTemplateArgs(), 3129 TemplateId->NumArgs); 3130 translateTemplateArguments(TemplateArgsPtr, 3131 TemplateArgs); 3132 TemplateArgsPtr.release(); 3133 3134 HasExplicitTemplateArgs = true; 3135 3136 if (FunctionTemplate) { 3137 // FIXME: Diagnose function template with explicit template 3138 // arguments. 3139 HasExplicitTemplateArgs = false; 3140 } else if (!isFunctionTemplateSpecialization && 3141 !D.getDeclSpec().isFriendSpecified()) { 3142 // We have encountered something that the user meant to be a 3143 // specialization (because it has explicitly-specified template 3144 // arguments) but that was not introduced with a "template<>" (or had 3145 // too few of them). 3146 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3147 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3148 << CodeModificationHint::CreateInsertion( 3149 D.getDeclSpec().getSourceRange().getBegin(), 3150 "template<> "); 3151 isFunctionTemplateSpecialization = true; 3152 } 3153 } 3154 3155 if (isFunctionTemplateSpecialization) { 3156 if (CheckFunctionTemplateSpecialization(NewFD, 3157 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3158 Previous)) 3159 NewFD->setInvalidDecl(); 3160 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3161 CheckMemberSpecialization(NewFD, Previous)) 3162 NewFD->setInvalidDecl(); 3163 3164 // Perform semantic checking on the function declaration. 3165 bool OverloadableAttrRequired = false; // FIXME: HACK! 3166 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3167 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3168 3169 assert((NewFD->isInvalidDecl() || !Redeclaration || 3170 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3171 "previous declaration set still overloaded"); 3172 3173 // If we have a function template, check the template parameter 3174 // list. This will check and merge default template arguments. 3175 if (FunctionTemplate) { 3176 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3177 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3178 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3179 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3180 : TPC_FunctionTemplate); 3181 } 3182 3183 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3184 // An out-of-line member function declaration must also be a 3185 // definition (C++ [dcl.meaning]p1). 3186 // Note that this is not the case for explicit specializations of 3187 // function templates or member functions of class templates, per 3188 // C++ [temp.expl.spec]p2. 3189 if (!IsFunctionDefinition && !isFriend && 3190 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3191 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3192 << D.getCXXScopeSpec().getRange(); 3193 NewFD->setInvalidDecl(); 3194 } else if (!Redeclaration) { 3195 // The user tried to provide an out-of-line definition for a 3196 // function that is a member of a class or namespace, but there 3197 // was no such member function declared (C++ [class.mfct]p2, 3198 // C++ [namespace.memdef]p2). For example: 3199 // 3200 // class X { 3201 // void f() const; 3202 // }; 3203 // 3204 // void X::f() { } // ill-formed 3205 // 3206 // Complain about this problem, and attempt to suggest close 3207 // matches (e.g., those that differ only in cv-qualifiers and 3208 // whether the parameter types are references). 3209 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3210 << Name << DC << D.getCXXScopeSpec().getRange(); 3211 NewFD->setInvalidDecl(); 3212 3213 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3214 ForRedeclaration); 3215 LookupQualifiedName(Prev, DC); 3216 assert(!Prev.isAmbiguous() && 3217 "Cannot have an ambiguity in previous-declaration lookup"); 3218 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3219 Func != FuncEnd; ++Func) { 3220 if (isa<FunctionDecl>(*Func) && 3221 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3222 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3223 } 3224 } 3225 } 3226 3227 // Handle attributes. We need to have merged decls when handling attributes 3228 // (for example to check for conflicts, etc). 3229 // FIXME: This needs to happen before we merge declarations. Then, 3230 // let attribute merging cope with attribute conflicts. 3231 ProcessDeclAttributes(S, NewFD, D); 3232 3233 // attributes declared post-definition are currently ignored 3234 if (Redeclaration && Previous.isSingleResult()) { 3235 const FunctionDecl *Def; 3236 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3237 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3238 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3239 Diag(Def->getLocation(), diag::note_previous_definition); 3240 } 3241 } 3242 3243 AddKnownFunctionAttributes(NewFD); 3244 3245 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3246 // If a function name is overloadable in C, then every function 3247 // with that name must be marked "overloadable". 3248 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3249 << Redeclaration << NewFD; 3250 if (!Previous.empty()) 3251 Diag(Previous.getRepresentativeDecl()->getLocation(), 3252 diag::note_attribute_overloadable_prev_overload); 3253 NewFD->addAttr(::new (Context) OverloadableAttr()); 3254 } 3255 3256 // If this is a locally-scoped extern C function, update the 3257 // map of such names. 3258 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3259 && !NewFD->isInvalidDecl()) 3260 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3261 3262 // Set this FunctionDecl's range up to the right paren. 3263 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3264 3265 if (FunctionTemplate && NewFD->isInvalidDecl()) 3266 FunctionTemplate->setInvalidDecl(); 3267 3268 if (FunctionTemplate) 3269 return FunctionTemplate; 3270 3271 return NewFD; 3272} 3273 3274/// \brief Perform semantic checking of a new function declaration. 3275/// 3276/// Performs semantic analysis of the new function declaration 3277/// NewFD. This routine performs all semantic checking that does not 3278/// require the actual declarator involved in the declaration, and is 3279/// used both for the declaration of functions as they are parsed 3280/// (called via ActOnDeclarator) and for the declaration of functions 3281/// that have been instantiated via C++ template instantiation (called 3282/// via InstantiateDecl). 3283/// 3284/// \param IsExplicitSpecialiation whether this new function declaration is 3285/// an explicit specialization of the previous declaration. 3286/// 3287/// This sets NewFD->isInvalidDecl() to true if there was an error. 3288void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3289 LookupResult &Previous, 3290 bool IsExplicitSpecialization, 3291 bool &Redeclaration, 3292 bool &OverloadableAttrRequired) { 3293 // If NewFD is already known erroneous, don't do any of this checking. 3294 if (NewFD->isInvalidDecl()) 3295 return; 3296 3297 if (NewFD->getResultType()->isVariablyModifiedType()) { 3298 // Functions returning a variably modified type violate C99 6.7.5.2p2 3299 // because all functions have linkage. 3300 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3301 return NewFD->setInvalidDecl(); 3302 } 3303 3304 if (NewFD->isMain()) 3305 CheckMain(NewFD); 3306 3307 // Check for a previous declaration of this name. 3308 if (Previous.empty() && NewFD->isExternC()) { 3309 // Since we did not find anything by this name and we're declaring 3310 // an extern "C" function, look for a non-visible extern "C" 3311 // declaration with the same name. 3312 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3313 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3314 if (Pos != LocallyScopedExternalDecls.end()) 3315 Previous.addDecl(Pos->second); 3316 } 3317 3318 // Merge or overload the declaration with an existing declaration of 3319 // the same name, if appropriate. 3320 if (!Previous.empty()) { 3321 // Determine whether NewFD is an overload of PrevDecl or 3322 // a declaration that requires merging. If it's an overload, 3323 // there's no more work to do here; we'll just add the new 3324 // function to the scope. 3325 3326 NamedDecl *OldDecl = 0; 3327 if (!AllowOverloadingOfFunction(Previous, Context)) { 3328 Redeclaration = true; 3329 OldDecl = Previous.getFoundDecl(); 3330 } else { 3331 if (!getLangOptions().CPlusPlus) { 3332 OverloadableAttrRequired = true; 3333 3334 // Functions marked "overloadable" must have a prototype (that 3335 // we can't get through declaration merging). 3336 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3337 Diag(NewFD->getLocation(), 3338 diag::err_attribute_overloadable_no_prototype) 3339 << NewFD; 3340 Redeclaration = true; 3341 3342 // Turn this into a variadic function with no parameters. 3343 QualType R = Context.getFunctionType( 3344 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3345 0, 0, true, 0); 3346 NewFD->setType(R); 3347 return NewFD->setInvalidDecl(); 3348 } 3349 } 3350 3351 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3352 case Ovl_Match: 3353 Redeclaration = true; 3354 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3355 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3356 Redeclaration = false; 3357 } 3358 break; 3359 3360 case Ovl_NonFunction: 3361 Redeclaration = true; 3362 break; 3363 3364 case Ovl_Overload: 3365 Redeclaration = false; 3366 break; 3367 } 3368 } 3369 3370 if (Redeclaration) { 3371 // NewFD and OldDecl represent declarations that need to be 3372 // merged. 3373 if (MergeFunctionDecl(NewFD, OldDecl)) 3374 return NewFD->setInvalidDecl(); 3375 3376 Previous.clear(); 3377 Previous.addDecl(OldDecl); 3378 3379 if (FunctionTemplateDecl *OldTemplateDecl 3380 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3381 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3382 FunctionTemplateDecl *NewTemplateDecl 3383 = NewFD->getDescribedFunctionTemplate(); 3384 assert(NewTemplateDecl && "Template/non-template mismatch"); 3385 if (CXXMethodDecl *Method 3386 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3387 Method->setAccess(OldTemplateDecl->getAccess()); 3388 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3389 } 3390 3391 // If this is an explicit specialization of a member that is a function 3392 // template, mark it as a member specialization. 3393 if (IsExplicitSpecialization && 3394 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3395 NewTemplateDecl->setMemberSpecialization(); 3396 assert(OldTemplateDecl->isMemberSpecialization()); 3397 } 3398 } else { 3399 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3400 NewFD->setAccess(OldDecl->getAccess()); 3401 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3402 } 3403 } 3404 } 3405 3406 // Semantic checking for this function declaration (in isolation). 3407 if (getLangOptions().CPlusPlus) { 3408 // C++-specific checks. 3409 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3410 CheckConstructor(Constructor); 3411 } else if (CXXDestructorDecl *Destructor = 3412 dyn_cast<CXXDestructorDecl>(NewFD)) { 3413 CXXRecordDecl *Record = Destructor->getParent(); 3414 QualType ClassType = Context.getTypeDeclType(Record); 3415 3416 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3417 // type is dependent? Both gcc and edg can handle that. 3418 if (!ClassType->isDependentType()) { 3419 DeclarationName Name 3420 = Context.DeclarationNames.getCXXDestructorName( 3421 Context.getCanonicalType(ClassType)); 3422 if (NewFD->getDeclName() != Name) { 3423 Diag(NewFD->getLocation(), diag::err_destructor_name); 3424 return NewFD->setInvalidDecl(); 3425 } 3426 } 3427 3428 Record->setUserDeclaredDestructor(true); 3429 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3430 // user-defined destructor. 3431 Record->setPOD(false); 3432 3433 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3434 // declared destructor. 3435 // FIXME: C++0x: don't do this for "= default" destructors 3436 Record->setHasTrivialDestructor(false); 3437 } else if (CXXConversionDecl *Conversion 3438 = dyn_cast<CXXConversionDecl>(NewFD)) { 3439 ActOnConversionDeclarator(Conversion); 3440 } 3441 3442 // Find any virtual functions that this function overrides. 3443 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3444 if (!Method->isFunctionTemplateSpecialization() && 3445 !Method->getDescribedFunctionTemplate()) 3446 AddOverriddenMethods(Method->getParent(), Method); 3447 } 3448 3449 // Additional checks for the destructor; make sure we do this after we 3450 // figure out whether the destructor is virtual. 3451 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3452 if (!Destructor->getParent()->isDependentType()) 3453 CheckDestructor(Destructor); 3454 3455 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3456 if (NewFD->isOverloadedOperator() && 3457 CheckOverloadedOperatorDeclaration(NewFD)) 3458 return NewFD->setInvalidDecl(); 3459 3460 // In C++, check default arguments now that we have merged decls. Unless 3461 // the lexical context is the class, because in this case this is done 3462 // during delayed parsing anyway. 3463 if (!CurContext->isRecord()) 3464 CheckCXXDefaultArguments(NewFD); 3465 } 3466} 3467 3468void Sema::CheckMain(FunctionDecl* FD) { 3469 // C++ [basic.start.main]p3: A program that declares main to be inline 3470 // or static is ill-formed. 3471 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3472 // shall not appear in a declaration of main. 3473 // static main is not an error under C99, but we should warn about it. 3474 bool isInline = FD->isInlineSpecified(); 3475 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3476 if (isInline || isStatic) { 3477 unsigned diagID = diag::warn_unusual_main_decl; 3478 if (isInline || getLangOptions().CPlusPlus) 3479 diagID = diag::err_unusual_main_decl; 3480 3481 int which = isStatic + (isInline << 1) - 1; 3482 Diag(FD->getLocation(), diagID) << which; 3483 } 3484 3485 QualType T = FD->getType(); 3486 assert(T->isFunctionType() && "function decl is not of function type"); 3487 const FunctionType* FT = T->getAs<FunctionType>(); 3488 3489 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3490 // TODO: add a replacement fixit to turn the return type into 'int'. 3491 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3492 FD->setInvalidDecl(true); 3493 } 3494 3495 // Treat protoless main() as nullary. 3496 if (isa<FunctionNoProtoType>(FT)) return; 3497 3498 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3499 unsigned nparams = FTP->getNumArgs(); 3500 assert(FD->getNumParams() == nparams); 3501 3502 bool HasExtraParameters = (nparams > 3); 3503 3504 // Darwin passes an undocumented fourth argument of type char**. If 3505 // other platforms start sprouting these, the logic below will start 3506 // getting shifty. 3507 if (nparams == 4 && 3508 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3509 HasExtraParameters = false; 3510 3511 if (HasExtraParameters) { 3512 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3513 FD->setInvalidDecl(true); 3514 nparams = 3; 3515 } 3516 3517 // FIXME: a lot of the following diagnostics would be improved 3518 // if we had some location information about types. 3519 3520 QualType CharPP = 3521 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3522 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3523 3524 for (unsigned i = 0; i < nparams; ++i) { 3525 QualType AT = FTP->getArgType(i); 3526 3527 bool mismatch = true; 3528 3529 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3530 mismatch = false; 3531 else if (Expected[i] == CharPP) { 3532 // As an extension, the following forms are okay: 3533 // char const ** 3534 // char const * const * 3535 // char * const * 3536 3537 QualifierCollector qs; 3538 const PointerType* PT; 3539 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3540 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3541 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3542 qs.removeConst(); 3543 mismatch = !qs.empty(); 3544 } 3545 } 3546 3547 if (mismatch) { 3548 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3549 // TODO: suggest replacing given type with expected type 3550 FD->setInvalidDecl(true); 3551 } 3552 } 3553 3554 if (nparams == 1 && !FD->isInvalidDecl()) { 3555 Diag(FD->getLocation(), diag::warn_main_one_arg); 3556 } 3557} 3558 3559bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3560 // FIXME: Need strict checking. In C89, we need to check for 3561 // any assignment, increment, decrement, function-calls, or 3562 // commas outside of a sizeof. In C99, it's the same list, 3563 // except that the aforementioned are allowed in unevaluated 3564 // expressions. Everything else falls under the 3565 // "may accept other forms of constant expressions" exception. 3566 // (We never end up here for C++, so the constant expression 3567 // rules there don't matter.) 3568 if (Init->isConstantInitializer(Context)) 3569 return false; 3570 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3571 << Init->getSourceRange(); 3572 return true; 3573} 3574 3575void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3576 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3577} 3578 3579/// AddInitializerToDecl - Adds the initializer Init to the 3580/// declaration dcl. If DirectInit is true, this is C++ direct 3581/// initialization rather than copy initialization. 3582void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3583 Decl *RealDecl = dcl.getAs<Decl>(); 3584 // If there is no declaration, there was an error parsing it. Just ignore 3585 // the initializer. 3586 if (RealDecl == 0) 3587 return; 3588 3589 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3590 // With declarators parsed the way they are, the parser cannot 3591 // distinguish between a normal initializer and a pure-specifier. 3592 // Thus this grotesque test. 3593 IntegerLiteral *IL; 3594 Expr *Init = static_cast<Expr *>(init.get()); 3595 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3596 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3597 CheckPureMethod(Method, Init->getSourceRange()); 3598 else { 3599 Diag(Method->getLocation(), diag::err_member_function_initialization) 3600 << Method->getDeclName() << Init->getSourceRange(); 3601 Method->setInvalidDecl(); 3602 } 3603 return; 3604 } 3605 3606 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3607 if (!VDecl) { 3608 if (getLangOptions().CPlusPlus && 3609 RealDecl->getLexicalDeclContext()->isRecord() && 3610 isa<NamedDecl>(RealDecl)) 3611 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3612 << cast<NamedDecl>(RealDecl)->getDeclName(); 3613 else 3614 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3615 RealDecl->setInvalidDecl(); 3616 return; 3617 } 3618 3619 // A definition must end up with a complete type, which means it must be 3620 // complete with the restriction that an array type might be completed by the 3621 // initializer; note that later code assumes this restriction. 3622 QualType BaseDeclType = VDecl->getType(); 3623 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3624 BaseDeclType = Array->getElementType(); 3625 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3626 diag::err_typecheck_decl_incomplete_type)) { 3627 RealDecl->setInvalidDecl(); 3628 return; 3629 } 3630 3631 // The variable can not have an abstract class type. 3632 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3633 diag::err_abstract_type_in_decl, 3634 AbstractVariableType)) 3635 VDecl->setInvalidDecl(); 3636 3637 const VarDecl *Def = 0; 3638 if (VDecl->getDefinition(Def)) { 3639 Diag(VDecl->getLocation(), diag::err_redefinition) 3640 << VDecl->getDeclName(); 3641 Diag(Def->getLocation(), diag::note_previous_definition); 3642 VDecl->setInvalidDecl(); 3643 return; 3644 } 3645 3646 // Take ownership of the expression, now that we're sure we have somewhere 3647 // to put it. 3648 Expr *Init = init.takeAs<Expr>(); 3649 assert(Init && "missing initializer"); 3650 3651 // Capture the variable that is being initialized and the style of 3652 // initialization. 3653 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3654 3655 // FIXME: Poor source location information. 3656 InitializationKind Kind 3657 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3658 Init->getLocStart(), 3659 Init->getLocEnd()) 3660 : InitializationKind::CreateCopy(VDecl->getLocation(), 3661 Init->getLocStart()); 3662 3663 // Get the decls type and save a reference for later, since 3664 // CheckInitializerTypes may change it. 3665 QualType DclT = VDecl->getType(), SavT = DclT; 3666 if (VDecl->isBlockVarDecl()) { 3667 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3668 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3669 VDecl->setInvalidDecl(); 3670 } else if (!VDecl->isInvalidDecl()) { 3671 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3672 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3673 MultiExprArg(*this, (void**)&Init, 1), 3674 &DclT); 3675 if (Result.isInvalid()) { 3676 VDecl->setInvalidDecl(); 3677 return; 3678 } 3679 3680 Init = Result.takeAs<Expr>(); 3681 3682 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3683 // Don't check invalid declarations to avoid emitting useless diagnostics. 3684 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3685 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3686 CheckForConstantInitializer(Init, DclT); 3687 } 3688 } 3689 } else if (VDecl->isStaticDataMember() && 3690 VDecl->getLexicalDeclContext()->isRecord()) { 3691 // This is an in-class initialization for a static data member, e.g., 3692 // 3693 // struct S { 3694 // static const int value = 17; 3695 // }; 3696 3697 // Attach the initializer 3698 VDecl->setInit(Context, Init); 3699 3700 // C++ [class.mem]p4: 3701 // A member-declarator can contain a constant-initializer only 3702 // if it declares a static member (9.4) of const integral or 3703 // const enumeration type, see 9.4.2. 3704 QualType T = VDecl->getType(); 3705 if (!T->isDependentType() && 3706 (!Context.getCanonicalType(T).isConstQualified() || 3707 !T->isIntegralType())) { 3708 Diag(VDecl->getLocation(), diag::err_member_initialization) 3709 << VDecl->getDeclName() << Init->getSourceRange(); 3710 VDecl->setInvalidDecl(); 3711 } else { 3712 // C++ [class.static.data]p4: 3713 // If a static data member is of const integral or const 3714 // enumeration type, its declaration in the class definition 3715 // can specify a constant-initializer which shall be an 3716 // integral constant expression (5.19). 3717 if (!Init->isTypeDependent() && 3718 !Init->getType()->isIntegralType()) { 3719 // We have a non-dependent, non-integral or enumeration type. 3720 Diag(Init->getSourceRange().getBegin(), 3721 diag::err_in_class_initializer_non_integral_type) 3722 << Init->getType() << Init->getSourceRange(); 3723 VDecl->setInvalidDecl(); 3724 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3725 // Check whether the expression is a constant expression. 3726 llvm::APSInt Value; 3727 SourceLocation Loc; 3728 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3729 Diag(Loc, diag::err_in_class_initializer_non_constant) 3730 << Init->getSourceRange(); 3731 VDecl->setInvalidDecl(); 3732 } else if (!VDecl->getType()->isDependentType()) 3733 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3734 } 3735 } 3736 } else if (VDecl->isFileVarDecl()) { 3737 if (VDecl->getStorageClass() == VarDecl::Extern) 3738 Diag(VDecl->getLocation(), diag::warn_extern_init); 3739 if (!VDecl->isInvalidDecl()) { 3740 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3741 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3742 MultiExprArg(*this, (void**)&Init, 1), 3743 &DclT); 3744 if (Result.isInvalid()) { 3745 VDecl->setInvalidDecl(); 3746 return; 3747 } 3748 3749 Init = Result.takeAs<Expr>(); 3750 } 3751 3752 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3753 // Don't check invalid declarations to avoid emitting useless diagnostics. 3754 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3755 // C99 6.7.8p4. All file scoped initializers need to be constant. 3756 CheckForConstantInitializer(Init, DclT); 3757 } 3758 } 3759 // If the type changed, it means we had an incomplete type that was 3760 // completed by the initializer. For example: 3761 // int ary[] = { 1, 3, 5 }; 3762 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3763 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3764 VDecl->setType(DclT); 3765 Init->setType(DclT); 3766 } 3767 3768 Init = MaybeCreateCXXExprWithTemporaries(Init); 3769 // Attach the initializer to the decl. 3770 VDecl->setInit(Context, Init); 3771 3772 // If the previous declaration of VDecl was a tentative definition, 3773 // remove it from the set of tentative definitions. 3774 if (VDecl->getPreviousDeclaration() && 3775 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3776 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3777 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3778 } 3779 3780 if (getLangOptions().CPlusPlus) { 3781 // Make sure we mark the destructor as used if necessary. 3782 QualType InitType = VDecl->getType(); 3783 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3784 InitType = Context.getBaseElementType(Array); 3785 if (InitType->isRecordType()) 3786 FinalizeVarWithDestructor(VDecl, InitType); 3787 } 3788 3789 return; 3790} 3791 3792void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3793 bool TypeContainsUndeducedAuto) { 3794 Decl *RealDecl = dcl.getAs<Decl>(); 3795 3796 // If there is no declaration, there was an error parsing it. Just ignore it. 3797 if (RealDecl == 0) 3798 return; 3799 3800 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3801 QualType Type = Var->getType(); 3802 3803 // Record tentative definitions. 3804 if (Var->isTentativeDefinition(Context)) { 3805 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3806 InsertPair = 3807 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3808 3809 // Keep the latest definition in the map. If we see 'int i; int i;' we 3810 // want the second one in the map. 3811 InsertPair.first->second = Var; 3812 3813 // However, for the list, we don't care about the order, just make sure 3814 // that there are no dupes for a given declaration name. 3815 if (InsertPair.second) 3816 TentativeDefinitionList.push_back(Var->getDeclName()); 3817 } 3818 3819 // C++ [dcl.init.ref]p3: 3820 // The initializer can be omitted for a reference only in a 3821 // parameter declaration (8.3.5), in the declaration of a 3822 // function return type, in the declaration of a class member 3823 // within its class declaration (9.2), and where the extern 3824 // specifier is explicitly used. 3825 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3826 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3827 << Var->getDeclName() 3828 << SourceRange(Var->getLocation(), Var->getLocation()); 3829 Var->setInvalidDecl(); 3830 return; 3831 } 3832 3833 // C++0x [dcl.spec.auto]p3 3834 if (TypeContainsUndeducedAuto) { 3835 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3836 << Var->getDeclName() << Type; 3837 Var->setInvalidDecl(); 3838 return; 3839 } 3840 3841 // An array without size is an incomplete type, and there are no special 3842 // rules in C++ to make such a definition acceptable. 3843 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3844 !Var->hasExternalStorage()) { 3845 Diag(Var->getLocation(), 3846 diag::err_typecheck_incomplete_array_needs_initializer); 3847 Var->setInvalidDecl(); 3848 return; 3849 } 3850 3851 // C++ [temp.expl.spec]p15: 3852 // An explicit specialization of a static data member of a template is a 3853 // definition if the declaration includes an initializer; otherwise, it 3854 // is a declaration. 3855 if (Var->isStaticDataMember() && 3856 Var->getInstantiatedFromStaticDataMember() && 3857 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3858 return; 3859 3860 // C++ [dcl.init]p9: 3861 // If no initializer is specified for an object, and the object 3862 // is of (possibly cv-qualified) non-POD class type (or array 3863 // thereof), the object shall be default-initialized; if the 3864 // object is of const-qualified type, the underlying class type 3865 // shall have a user-declared default constructor. 3866 // 3867 // FIXME: Diagnose the "user-declared default constructor" bit. 3868 if (getLangOptions().CPlusPlus) { 3869 QualType InitType = Type; 3870 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3871 InitType = Context.getBaseElementType(Array); 3872 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3873 InitType->isRecordType() && !InitType->isDependentType()) { 3874 if (!RequireCompleteType(Var->getLocation(), InitType, 3875 diag::err_invalid_incomplete_type_use)) { 3876 InitializedEntity Entity 3877 = InitializedEntity::InitializeVariable(Var); 3878 InitializationKind Kind 3879 = InitializationKind::CreateDefault(Var->getLocation()); 3880 3881 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 3882 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 3883 MultiExprArg(*this, 0, 0)); 3884 if (Init.isInvalid()) 3885 Var->setInvalidDecl(); 3886 else { 3887 Var->setInit(Context, 3888 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 3889 FinalizeVarWithDestructor(Var, InitType); 3890 } 3891 } else { 3892 Var->setInvalidDecl(); 3893 } 3894 } 3895 3896 // The variable can not have an abstract class type. 3897 if (RequireNonAbstractType(Var->getLocation(), Type, 3898 diag::err_abstract_type_in_decl, 3899 AbstractVariableType)) 3900 Var->setInvalidDecl(); 3901 } 3902 3903#if 0 3904 // FIXME: Temporarily disabled because we are not properly parsing 3905 // linkage specifications on declarations, e.g., 3906 // 3907 // extern "C" const CGPoint CGPointerZero; 3908 // 3909 // C++ [dcl.init]p9: 3910 // 3911 // If no initializer is specified for an object, and the 3912 // object is of (possibly cv-qualified) non-POD class type (or 3913 // array thereof), the object shall be default-initialized; if 3914 // the object is of const-qualified type, the underlying class 3915 // type shall have a user-declared default 3916 // constructor. Otherwise, if no initializer is specified for 3917 // an object, the object and its subobjects, if any, have an 3918 // indeterminate initial value; if the object or any of its 3919 // subobjects are of const-qualified type, the program is 3920 // ill-formed. 3921 // 3922 // This isn't technically an error in C, so we don't diagnose it. 3923 // 3924 // FIXME: Actually perform the POD/user-defined default 3925 // constructor check. 3926 if (getLangOptions().CPlusPlus && 3927 Context.getCanonicalType(Type).isConstQualified() && 3928 !Var->hasExternalStorage()) 3929 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3930 << Var->getName() 3931 << SourceRange(Var->getLocation(), Var->getLocation()); 3932#endif 3933 } 3934} 3935 3936Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3937 DeclPtrTy *Group, 3938 unsigned NumDecls) { 3939 llvm::SmallVector<Decl*, 8> Decls; 3940 3941 if (DS.isTypeSpecOwned()) 3942 Decls.push_back((Decl*)DS.getTypeRep()); 3943 3944 for (unsigned i = 0; i != NumDecls; ++i) 3945 if (Decl *D = Group[i].getAs<Decl>()) 3946 Decls.push_back(D); 3947 3948 // Perform semantic analysis that depends on having fully processed both 3949 // the declarator and initializer. 3950 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3951 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3952 if (!IDecl) 3953 continue; 3954 QualType T = IDecl->getType(); 3955 3956 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3957 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3958 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3959 if (T->isDependentType()) { 3960 // If T is dependent, we should not require a complete type. 3961 // (RequireCompleteType shouldn't be called with dependent types.) 3962 // But we still can at least check if we've got an array of unspecified 3963 // size without an initializer. 3964 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3965 !IDecl->getInit()) { 3966 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3967 << T; 3968 IDecl->setInvalidDecl(); 3969 } 3970 } else if (!IDecl->isInvalidDecl()) { 3971 // If T is an incomplete array type with an initializer list that is 3972 // dependent on something, its size has not been fixed. We could attempt 3973 // to fix the size for such arrays, but we would still have to check 3974 // here for initializers containing a C++0x vararg expansion, e.g. 3975 // template <typename... Args> void f(Args... args) { 3976 // int vals[] = { args }; 3977 // } 3978 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3979 Expr *Init = IDecl->getInit(); 3980 if (IAT && Init && 3981 (Init->isTypeDependent() || Init->isValueDependent())) { 3982 // Check that the member type of the array is complete, at least. 3983 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3984 diag::err_typecheck_decl_incomplete_type)) 3985 IDecl->setInvalidDecl(); 3986 } else if (RequireCompleteType(IDecl->getLocation(), T, 3987 diag::err_typecheck_decl_incomplete_type)) 3988 IDecl->setInvalidDecl(); 3989 } 3990 } 3991 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3992 // object that has file scope without an initializer, and without a 3993 // storage-class specifier or with the storage-class specifier "static", 3994 // constitutes a tentative definition. Note: A tentative definition with 3995 // external linkage is valid (C99 6.2.2p5). 3996 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3997 if (const IncompleteArrayType *ArrayT 3998 = Context.getAsIncompleteArrayType(T)) { 3999 if (RequireCompleteType(IDecl->getLocation(), 4000 ArrayT->getElementType(), 4001 diag::err_illegal_decl_array_incomplete_type)) 4002 IDecl->setInvalidDecl(); 4003 } else if (IDecl->getStorageClass() == VarDecl::Static) { 4004 // C99 6.9.2p3: If the declaration of an identifier for an object is 4005 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4006 // declared type shall not be an incomplete type. 4007 // NOTE: code such as the following 4008 // static struct s; 4009 // struct s { int a; }; 4010 // is accepted by gcc. Hence here we issue a warning instead of 4011 // an error and we do not invalidate the static declaration. 4012 // NOTE: to avoid multiple warnings, only check the first declaration. 4013 if (IDecl->getPreviousDeclaration() == 0) 4014 RequireCompleteType(IDecl->getLocation(), T, 4015 diag::ext_typecheck_decl_incomplete_type); 4016 } 4017 } 4018 } 4019 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4020 Decls.data(), Decls.size())); 4021} 4022 4023 4024/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4025/// to introduce parameters into function prototype scope. 4026Sema::DeclPtrTy 4027Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4028 const DeclSpec &DS = D.getDeclSpec(); 4029 4030 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4031 VarDecl::StorageClass StorageClass = VarDecl::None; 4032 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4033 StorageClass = VarDecl::Register; 4034 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4035 Diag(DS.getStorageClassSpecLoc(), 4036 diag::err_invalid_storage_class_in_func_decl); 4037 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4038 } 4039 4040 if (D.getDeclSpec().isThreadSpecified()) 4041 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4042 4043 DiagnoseFunctionSpecifiers(D); 4044 4045 // Check that there are no default arguments inside the type of this 4046 // parameter (C++ only). 4047 if (getLangOptions().CPlusPlus) 4048 CheckExtraCXXDefaultArguments(D); 4049 4050 TypeSourceInfo *TInfo = 0; 4051 TagDecl *OwnedDecl = 0; 4052 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4053 4054 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4055 // C++ [dcl.fct]p6: 4056 // Types shall not be defined in return or parameter types. 4057 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4058 << Context.getTypeDeclType(OwnedDecl); 4059 } 4060 4061 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 4062 // Can this happen for params? We already checked that they don't conflict 4063 // among each other. Here they can only shadow globals, which is ok. 4064 IdentifierInfo *II = D.getIdentifier(); 4065 if (II) { 4066 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 4067 if (PrevDecl->isTemplateParameter()) { 4068 // Maybe we will complain about the shadowed template parameter. 4069 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4070 // Just pretend that we didn't see the previous declaration. 4071 PrevDecl = 0; 4072 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4073 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4074 4075 // Recover by removing the name 4076 II = 0; 4077 D.SetIdentifier(0, D.getIdentifierLoc()); 4078 } 4079 } 4080 } 4081 4082 // Parameters can not be abstract class types. 4083 // For record types, this is done by the AbstractClassUsageDiagnoser once 4084 // the class has been completely parsed. 4085 if (!CurContext->isRecord() && 4086 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4087 diag::err_abstract_type_in_decl, 4088 AbstractParamType)) 4089 D.setInvalidType(true); 4090 4091 QualType T = adjustParameterType(parmDeclType); 4092 4093 ParmVarDecl *New 4094 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 4095 T, TInfo, StorageClass, 0); 4096 4097 if (D.isInvalidType()) 4098 New->setInvalidDecl(); 4099 4100 // Parameter declarators cannot be interface types. All ObjC objects are 4101 // passed by reference. 4102 if (T->isObjCInterfaceType()) { 4103 Diag(D.getIdentifierLoc(), 4104 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4105 New->setInvalidDecl(); 4106 } 4107 4108 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4109 if (D.getCXXScopeSpec().isSet()) { 4110 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4111 << D.getCXXScopeSpec().getRange(); 4112 New->setInvalidDecl(); 4113 } 4114 4115 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4116 // duration shall not be qualified by an address-space qualifier." 4117 // Since all parameters have automatic store duration, they can not have 4118 // an address space. 4119 if (T.getAddressSpace() != 0) { 4120 Diag(D.getIdentifierLoc(), 4121 diag::err_arg_with_address_space); 4122 New->setInvalidDecl(); 4123 } 4124 4125 4126 // Add the parameter declaration into this scope. 4127 S->AddDecl(DeclPtrTy::make(New)); 4128 if (II) 4129 IdResolver.AddDecl(New); 4130 4131 ProcessDeclAttributes(S, New, D); 4132 4133 if (New->hasAttr<BlocksAttr>()) { 4134 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4135 } 4136 return DeclPtrTy::make(New); 4137} 4138 4139void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4140 SourceLocation LocAfterDecls) { 4141 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4142 "Not a function declarator!"); 4143 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4144 4145 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4146 // for a K&R function. 4147 if (!FTI.hasPrototype) { 4148 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4149 --i; 4150 if (FTI.ArgInfo[i].Param == 0) { 4151 llvm::SmallString<256> Code; 4152 llvm::raw_svector_ostream(Code) << " int " 4153 << FTI.ArgInfo[i].Ident->getName() 4154 << ";\n"; 4155 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4156 << FTI.ArgInfo[i].Ident 4157 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4158 4159 // Implicitly declare the argument as type 'int' for lack of a better 4160 // type. 4161 DeclSpec DS; 4162 const char* PrevSpec; // unused 4163 unsigned DiagID; // unused 4164 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4165 PrevSpec, DiagID); 4166 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4167 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4168 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4169 } 4170 } 4171 } 4172} 4173 4174Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4175 Declarator &D) { 4176 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4177 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4178 "Not a function declarator!"); 4179 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4180 4181 if (FTI.hasPrototype) { 4182 // FIXME: Diagnose arguments without names in C. 4183 } 4184 4185 Scope *ParentScope = FnBodyScope->getParent(); 4186 4187 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4188 MultiTemplateParamsArg(*this), 4189 /*IsFunctionDefinition=*/true); 4190 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4191} 4192 4193static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4194 // Don't warn about invalid declarations. 4195 if (FD->isInvalidDecl()) 4196 return false; 4197 4198 // Or declarations that aren't global. 4199 if (!FD->isGlobal()) 4200 return false; 4201 4202 // Don't warn about C++ member functions. 4203 if (isa<CXXMethodDecl>(FD)) 4204 return false; 4205 4206 // Don't warn about 'main'. 4207 if (FD->isMain()) 4208 return false; 4209 4210 // Don't warn about inline functions. 4211 if (FD->isInlineSpecified()) 4212 return false; 4213 4214 // Don't warn about function templates. 4215 if (FD->getDescribedFunctionTemplate()) 4216 return false; 4217 4218 // Don't warn about function template specializations. 4219 if (FD->isFunctionTemplateSpecialization()) 4220 return false; 4221 4222 bool MissingPrototype = true; 4223 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4224 Prev; Prev = Prev->getPreviousDeclaration()) { 4225 // Ignore any declarations that occur in function or method 4226 // scope, because they aren't visible from the header. 4227 if (Prev->getDeclContext()->isFunctionOrMethod()) 4228 continue; 4229 4230 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4231 break; 4232 } 4233 4234 return MissingPrototype; 4235} 4236 4237Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4238 // Clear the last template instantiation error context. 4239 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4240 4241 if (!D) 4242 return D; 4243 FunctionDecl *FD = 0; 4244 4245 if (FunctionTemplateDecl *FunTmpl 4246 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4247 FD = FunTmpl->getTemplatedDecl(); 4248 else 4249 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4250 4251 CurFunctionNeedsScopeChecking = false; 4252 4253 // See if this is a redefinition. 4254 const FunctionDecl *Definition; 4255 if (FD->getBody(Definition)) { 4256 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4257 Diag(Definition->getLocation(), diag::note_previous_definition); 4258 } 4259 4260 // Builtin functions cannot be defined. 4261 if (unsigned BuiltinID = FD->getBuiltinID()) { 4262 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4263 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4264 FD->setInvalidDecl(); 4265 } 4266 } 4267 4268 // The return type of a function definition must be complete 4269 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4270 QualType ResultType = FD->getResultType(); 4271 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4272 !FD->isInvalidDecl() && 4273 RequireCompleteType(FD->getLocation(), ResultType, 4274 diag::err_func_def_incomplete_result)) 4275 FD->setInvalidDecl(); 4276 4277 // GNU warning -Wmissing-prototypes: 4278 // Warn if a global function is defined without a previous 4279 // prototype declaration. This warning is issued even if the 4280 // definition itself provides a prototype. The aim is to detect 4281 // global functions that fail to be declared in header files. 4282 if (ShouldWarnAboutMissingPrototype(FD)) 4283 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4284 4285 if (FnBodyScope) 4286 PushDeclContext(FnBodyScope, FD); 4287 4288 // Check the validity of our function parameters 4289 CheckParmsForFunctionDef(FD); 4290 4291 // Introduce our parameters into the function scope 4292 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4293 ParmVarDecl *Param = FD->getParamDecl(p); 4294 Param->setOwningFunction(FD); 4295 4296 // If this has an identifier, add it to the scope stack. 4297 if (Param->getIdentifier() && FnBodyScope) 4298 PushOnScopeChains(Param, FnBodyScope); 4299 } 4300 4301 // Checking attributes of current function definition 4302 // dllimport attribute. 4303 if (FD->getAttr<DLLImportAttr>() && 4304 (!FD->getAttr<DLLExportAttr>())) { 4305 // dllimport attribute cannot be applied to definition. 4306 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4307 Diag(FD->getLocation(), 4308 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4309 << "dllimport"; 4310 FD->setInvalidDecl(); 4311 return DeclPtrTy::make(FD); 4312 } else { 4313 // If a symbol previously declared dllimport is later defined, the 4314 // attribute is ignored in subsequent references, and a warning is 4315 // emitted. 4316 Diag(FD->getLocation(), 4317 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4318 << FD->getNameAsCString() << "dllimport"; 4319 } 4320 } 4321 return DeclPtrTy::make(FD); 4322} 4323 4324Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4325 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4326} 4327 4328Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4329 bool IsInstantiation) { 4330 Decl *dcl = D.getAs<Decl>(); 4331 Stmt *Body = BodyArg.takeAs<Stmt>(); 4332 4333 FunctionDecl *FD = 0; 4334 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4335 if (FunTmpl) 4336 FD = FunTmpl->getTemplatedDecl(); 4337 else 4338 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4339 4340 if (FD) { 4341 FD->setBody(Body); 4342 if (FD->isMain()) 4343 // C and C++ allow for main to automagically return 0. 4344 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4345 FD->setHasImplicitReturnZero(true); 4346 else 4347 CheckFallThroughForFunctionDef(FD, Body); 4348 4349 if (!FD->isInvalidDecl()) 4350 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4351 4352 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4353 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4354 4355 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4356 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4357 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4358 MD->setBody(Body); 4359 CheckFallThroughForFunctionDef(MD, Body); 4360 MD->setEndLoc(Body->getLocEnd()); 4361 4362 if (!MD->isInvalidDecl()) 4363 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4364 } else { 4365 Body->Destroy(Context); 4366 return DeclPtrTy(); 4367 } 4368 if (!IsInstantiation) 4369 PopDeclContext(); 4370 4371 // Verify and clean out per-function state. 4372 4373 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4374 4375 // Check goto/label use. 4376 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4377 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4378 LabelStmt *L = I->second; 4379 4380 // Verify that we have no forward references left. If so, there was a goto 4381 // or address of a label taken, but no definition of it. Label fwd 4382 // definitions are indicated with a null substmt. 4383 if (L->getSubStmt() != 0) 4384 continue; 4385 4386 // Emit error. 4387 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4388 4389 // At this point, we have gotos that use the bogus label. Stitch it into 4390 // the function body so that they aren't leaked and that the AST is well 4391 // formed. 4392 if (Body == 0) { 4393 // The whole function wasn't parsed correctly, just delete this. 4394 L->Destroy(Context); 4395 continue; 4396 } 4397 4398 // Otherwise, the body is valid: we want to stitch the label decl into the 4399 // function somewhere so that it is properly owned and so that the goto 4400 // has a valid target. Do this by creating a new compound stmt with the 4401 // label in it. 4402 4403 // Give the label a sub-statement. 4404 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4405 4406 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4407 cast<CXXTryStmt>(Body)->getTryBlock() : 4408 cast<CompoundStmt>(Body); 4409 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4410 Elements.push_back(L); 4411 Compound->setStmts(Context, &Elements[0], Elements.size()); 4412 } 4413 FunctionLabelMap.clear(); 4414 4415 if (!Body) return D; 4416 4417 // Verify that that gotos and switch cases don't jump into scopes illegally. 4418 if (CurFunctionNeedsScopeChecking) 4419 DiagnoseInvalidJumps(Body); 4420 4421 // C++ constructors that have function-try-blocks can't have return 4422 // statements in the handlers of that block. (C++ [except.handle]p14) 4423 // Verify this. 4424 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4425 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4426 4427 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4428 MarkBaseAndMemberDestructorsReferenced(Destructor); 4429 4430 // If any errors have occurred, clear out any temporaries that may have 4431 // been leftover. This ensures that these temporaries won't be picked up for 4432 // deletion in some later function. 4433 if (PP.getDiagnostics().hasErrorOccurred()) 4434 ExprTemporaries.clear(); 4435 4436 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4437 return D; 4438} 4439 4440/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4441/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4442NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4443 IdentifierInfo &II, Scope *S) { 4444 // Before we produce a declaration for an implicitly defined 4445 // function, see whether there was a locally-scoped declaration of 4446 // this name as a function or variable. If so, use that 4447 // (non-visible) declaration, and complain about it. 4448 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4449 = LocallyScopedExternalDecls.find(&II); 4450 if (Pos != LocallyScopedExternalDecls.end()) { 4451 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4452 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4453 return Pos->second; 4454 } 4455 4456 // Extension in C99. Legal in C90, but warn about it. 4457 if (II.getName().startswith("__builtin_")) 4458 Diag(Loc, diag::warn_builtin_unknown) << &II; 4459 else if (getLangOptions().C99) 4460 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4461 else 4462 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4463 4464 // Set a Declarator for the implicit definition: int foo(); 4465 const char *Dummy; 4466 DeclSpec DS; 4467 unsigned DiagID; 4468 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4469 Error = Error; // Silence warning. 4470 assert(!Error && "Error setting up implicit decl!"); 4471 Declarator D(DS, Declarator::BlockContext); 4472 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4473 0, 0, false, SourceLocation(), 4474 false, 0,0,0, Loc, Loc, D), 4475 SourceLocation()); 4476 D.SetIdentifier(&II, Loc); 4477 4478 // Insert this function into translation-unit scope. 4479 4480 DeclContext *PrevDC = CurContext; 4481 CurContext = Context.getTranslationUnitDecl(); 4482 4483 FunctionDecl *FD = 4484 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4485 FD->setImplicit(); 4486 4487 CurContext = PrevDC; 4488 4489 AddKnownFunctionAttributes(FD); 4490 4491 return FD; 4492} 4493 4494/// \brief Adds any function attributes that we know a priori based on 4495/// the declaration of this function. 4496/// 4497/// These attributes can apply both to implicitly-declared builtins 4498/// (like __builtin___printf_chk) or to library-declared functions 4499/// like NSLog or printf. 4500void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4501 if (FD->isInvalidDecl()) 4502 return; 4503 4504 // If this is a built-in function, map its builtin attributes to 4505 // actual attributes. 4506 if (unsigned BuiltinID = FD->getBuiltinID()) { 4507 // Handle printf-formatting attributes. 4508 unsigned FormatIdx; 4509 bool HasVAListArg; 4510 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4511 if (!FD->getAttr<FormatAttr>()) 4512 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4513 HasVAListArg ? 0 : FormatIdx + 2)); 4514 } 4515 4516 // Mark const if we don't care about errno and that is the only 4517 // thing preventing the function from being const. This allows 4518 // IRgen to use LLVM intrinsics for such functions. 4519 if (!getLangOptions().MathErrno && 4520 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4521 if (!FD->getAttr<ConstAttr>()) 4522 FD->addAttr(::new (Context) ConstAttr()); 4523 } 4524 4525 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4526 FD->addAttr(::new (Context) NoReturnAttr()); 4527 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4528 FD->addAttr(::new (Context) NoThrowAttr()); 4529 if (Context.BuiltinInfo.isConst(BuiltinID)) 4530 FD->addAttr(::new (Context) ConstAttr()); 4531 } 4532 4533 IdentifierInfo *Name = FD->getIdentifier(); 4534 if (!Name) 4535 return; 4536 if ((!getLangOptions().CPlusPlus && 4537 FD->getDeclContext()->isTranslationUnit()) || 4538 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4539 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4540 LinkageSpecDecl::lang_c)) { 4541 // Okay: this could be a libc/libm/Objective-C function we know 4542 // about. 4543 } else 4544 return; 4545 4546 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4547 // FIXME: NSLog and NSLogv should be target specific 4548 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4549 // FIXME: We known better than our headers. 4550 const_cast<FormatAttr *>(Format)->setType("printf"); 4551 } else 4552 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4553 Name->isStr("NSLogv") ? 0 : 2)); 4554 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4555 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4556 // target-specific builtins, perhaps? 4557 if (!FD->getAttr<FormatAttr>()) 4558 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4559 Name->isStr("vasprintf") ? 0 : 3)); 4560 } 4561} 4562 4563TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4564 TypeSourceInfo *TInfo) { 4565 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4566 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4567 4568 if (!TInfo) { 4569 assert(D.isInvalidType() && "no declarator info for valid type"); 4570 TInfo = Context.getTrivialTypeSourceInfo(T); 4571 } 4572 4573 // Scope manipulation handled by caller. 4574 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4575 D.getIdentifierLoc(), 4576 D.getIdentifier(), 4577 TInfo); 4578 4579 if (const TagType *TT = T->getAs<TagType>()) { 4580 TagDecl *TD = TT->getDecl(); 4581 4582 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4583 // keep track of the TypedefDecl. 4584 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4585 TD->setTypedefForAnonDecl(NewTD); 4586 } 4587 4588 if (D.isInvalidType()) 4589 NewTD->setInvalidDecl(); 4590 return NewTD; 4591} 4592 4593 4594/// \brief Determine whether a tag with a given kind is acceptable 4595/// as a redeclaration of the given tag declaration. 4596/// 4597/// \returns true if the new tag kind is acceptable, false otherwise. 4598bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4599 TagDecl::TagKind NewTag, 4600 SourceLocation NewTagLoc, 4601 const IdentifierInfo &Name) { 4602 // C++ [dcl.type.elab]p3: 4603 // The class-key or enum keyword present in the 4604 // elaborated-type-specifier shall agree in kind with the 4605 // declaration to which the name in theelaborated-type-specifier 4606 // refers. This rule also applies to the form of 4607 // elaborated-type-specifier that declares a class-name or 4608 // friend class since it can be construed as referring to the 4609 // definition of the class. Thus, in any 4610 // elaborated-type-specifier, the enum keyword shall be used to 4611 // refer to an enumeration (7.2), the union class-keyshall be 4612 // used to refer to a union (clause 9), and either the class or 4613 // struct class-key shall be used to refer to a class (clause 9) 4614 // declared using the class or struct class-key. 4615 TagDecl::TagKind OldTag = Previous->getTagKind(); 4616 if (OldTag == NewTag) 4617 return true; 4618 4619 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4620 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4621 // Warn about the struct/class tag mismatch. 4622 bool isTemplate = false; 4623 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4624 isTemplate = Record->getDescribedClassTemplate(); 4625 4626 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4627 << (NewTag == TagDecl::TK_class) 4628 << isTemplate << &Name 4629 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4630 OldTag == TagDecl::TK_class? "class" : "struct"); 4631 Diag(Previous->getLocation(), diag::note_previous_use); 4632 return true; 4633 } 4634 return false; 4635} 4636 4637/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4638/// former case, Name will be non-null. In the later case, Name will be null. 4639/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4640/// reference/declaration/definition of a tag. 4641Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4642 SourceLocation KWLoc, const CXXScopeSpec &SS, 4643 IdentifierInfo *Name, SourceLocation NameLoc, 4644 AttributeList *Attr, AccessSpecifier AS, 4645 MultiTemplateParamsArg TemplateParameterLists, 4646 bool &OwnedDecl, bool &IsDependent) { 4647 // If this is not a definition, it must have a name. 4648 assert((Name != 0 || TUK == TUK_Definition) && 4649 "Nameless record must be a definition!"); 4650 4651 OwnedDecl = false; 4652 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4653 4654 // FIXME: Check explicit specializations more carefully. 4655 bool isExplicitSpecialization = false; 4656 if (TUK != TUK_Reference) { 4657 if (TemplateParameterList *TemplateParams 4658 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4659 (TemplateParameterList**)TemplateParameterLists.get(), 4660 TemplateParameterLists.size(), 4661 isExplicitSpecialization)) { 4662 if (TemplateParams->size() > 0) { 4663 // This is a declaration or definition of a class template (which may 4664 // be a member of another template). 4665 OwnedDecl = false; 4666 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4667 SS, Name, NameLoc, Attr, 4668 TemplateParams, 4669 AS); 4670 TemplateParameterLists.release(); 4671 return Result.get(); 4672 } else { 4673 // The "template<>" header is extraneous. 4674 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4675 << ElaboratedType::getNameForTagKind(Kind) << Name; 4676 isExplicitSpecialization = true; 4677 } 4678 } 4679 4680 TemplateParameterLists.release(); 4681 } 4682 4683 DeclContext *SearchDC = CurContext; 4684 DeclContext *DC = CurContext; 4685 bool isStdBadAlloc = false; 4686 bool Invalid = false; 4687 4688 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4689 : NotForRedeclaration); 4690 4691 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4692 4693 if (Name && SS.isNotEmpty()) { 4694 // We have a nested-name tag ('struct foo::bar'). 4695 4696 // Check for invalid 'foo::'. 4697 if (SS.isInvalid()) { 4698 Name = 0; 4699 goto CreateNewDecl; 4700 } 4701 4702 // If this is a friend or a reference to a class in a dependent 4703 // context, don't try to make a decl for it. 4704 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4705 DC = computeDeclContext(SS, false); 4706 if (!DC) { 4707 IsDependent = true; 4708 return DeclPtrTy(); 4709 } 4710 } 4711 4712 if (RequireCompleteDeclContext(SS)) 4713 return DeclPtrTy::make((Decl *)0); 4714 4715 DC = computeDeclContext(SS, true); 4716 SearchDC = DC; 4717 // Look-up name inside 'foo::'. 4718 LookupQualifiedName(Previous, DC); 4719 4720 if (Previous.isAmbiguous()) 4721 return DeclPtrTy(); 4722 4723 // A tag 'foo::bar' must already exist. 4724 if (Previous.empty()) { 4725 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4726 Name = 0; 4727 Invalid = true; 4728 goto CreateNewDecl; 4729 } 4730 } else if (Name) { 4731 // If this is a named struct, check to see if there was a previous forward 4732 // declaration or definition. 4733 // FIXME: We're looking into outer scopes here, even when we 4734 // shouldn't be. Doing so can result in ambiguities that we 4735 // shouldn't be diagnosing. 4736 LookupName(Previous, S); 4737 4738 // Note: there used to be some attempt at recovery here. 4739 if (Previous.isAmbiguous()) 4740 return DeclPtrTy(); 4741 4742 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4743 // FIXME: This makes sure that we ignore the contexts associated 4744 // with C structs, unions, and enums when looking for a matching 4745 // tag declaration or definition. See the similar lookup tweak 4746 // in Sema::LookupName; is there a better way to deal with this? 4747 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4748 SearchDC = SearchDC->getParent(); 4749 } 4750 } 4751 4752 if (Previous.isSingleResult() && 4753 Previous.getFoundDecl()->isTemplateParameter()) { 4754 // Maybe we will complain about the shadowed template parameter. 4755 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4756 // Just pretend that we didn't see the previous declaration. 4757 Previous.clear(); 4758 } 4759 4760 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4761 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4762 // This is a declaration of or a reference to "std::bad_alloc". 4763 isStdBadAlloc = true; 4764 4765 if (Previous.empty() && StdBadAlloc) { 4766 // std::bad_alloc has been implicitly declared (but made invisible to 4767 // name lookup). Fill in this implicit declaration as the previous 4768 // declaration, so that the declarations get chained appropriately. 4769 Previous.addDecl(StdBadAlloc); 4770 } 4771 } 4772 4773 if (!Previous.empty()) { 4774 assert(Previous.isSingleResult()); 4775 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4776 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4777 // If this is a use of a previous tag, or if the tag is already declared 4778 // in the same scope (so that the definition/declaration completes or 4779 // rementions the tag), reuse the decl. 4780 if (TUK == TUK_Reference || TUK == TUK_Friend || 4781 isDeclInScope(PrevDecl, SearchDC, S)) { 4782 // Make sure that this wasn't declared as an enum and now used as a 4783 // struct or something similar. 4784 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4785 bool SafeToContinue 4786 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4787 Kind != TagDecl::TK_enum); 4788 if (SafeToContinue) 4789 Diag(KWLoc, diag::err_use_with_wrong_tag) 4790 << Name 4791 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4792 PrevTagDecl->getKindName()); 4793 else 4794 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4795 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4796 4797 if (SafeToContinue) 4798 Kind = PrevTagDecl->getTagKind(); 4799 else { 4800 // Recover by making this an anonymous redefinition. 4801 Name = 0; 4802 Previous.clear(); 4803 Invalid = true; 4804 } 4805 } 4806 4807 if (!Invalid) { 4808 // If this is a use, just return the declaration we found. 4809 4810 // FIXME: In the future, return a variant or some other clue 4811 // for the consumer of this Decl to know it doesn't own it. 4812 // For our current ASTs this shouldn't be a problem, but will 4813 // need to be changed with DeclGroups. 4814 if (TUK == TUK_Reference || TUK == TUK_Friend) 4815 return DeclPtrTy::make(PrevTagDecl); 4816 4817 // Diagnose attempts to redefine a tag. 4818 if (TUK == TUK_Definition) { 4819 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4820 // If we're defining a specialization and the previous definition 4821 // is from an implicit instantiation, don't emit an error 4822 // here; we'll catch this in the general case below. 4823 if (!isExplicitSpecialization || 4824 !isa<CXXRecordDecl>(Def) || 4825 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4826 == TSK_ExplicitSpecialization) { 4827 Diag(NameLoc, diag::err_redefinition) << Name; 4828 Diag(Def->getLocation(), diag::note_previous_definition); 4829 // If this is a redefinition, recover by making this 4830 // struct be anonymous, which will make any later 4831 // references get the previous definition. 4832 Name = 0; 4833 Previous.clear(); 4834 Invalid = true; 4835 } 4836 } else { 4837 // If the type is currently being defined, complain 4838 // about a nested redefinition. 4839 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4840 if (Tag->isBeingDefined()) { 4841 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4842 Diag(PrevTagDecl->getLocation(), 4843 diag::note_previous_definition); 4844 Name = 0; 4845 Previous.clear(); 4846 Invalid = true; 4847 } 4848 } 4849 4850 // Okay, this is definition of a previously declared or referenced 4851 // tag PrevDecl. We're going to create a new Decl for it. 4852 } 4853 } 4854 // If we get here we have (another) forward declaration or we 4855 // have a definition. Just create a new decl. 4856 4857 } else { 4858 // If we get here, this is a definition of a new tag type in a nested 4859 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4860 // new decl/type. We set PrevDecl to NULL so that the entities 4861 // have distinct types. 4862 Previous.clear(); 4863 } 4864 // If we get here, we're going to create a new Decl. If PrevDecl 4865 // is non-NULL, it's a definition of the tag declared by 4866 // PrevDecl. If it's NULL, we have a new definition. 4867 } else { 4868 // PrevDecl is a namespace, template, or anything else 4869 // that lives in the IDNS_Tag identifier namespace. 4870 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4871 // The tag name clashes with a namespace name, issue an error and 4872 // recover by making this tag be anonymous. 4873 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4874 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4875 Name = 0; 4876 Previous.clear(); 4877 Invalid = true; 4878 } else { 4879 // The existing declaration isn't relevant to us; we're in a 4880 // new scope, so clear out the previous declaration. 4881 Previous.clear(); 4882 } 4883 } 4884 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4885 // C++ [basic.scope.pdecl]p5: 4886 // -- for an elaborated-type-specifier of the form 4887 // 4888 // class-key identifier 4889 // 4890 // if the elaborated-type-specifier is used in the 4891 // decl-specifier-seq or parameter-declaration-clause of a 4892 // function defined in namespace scope, the identifier is 4893 // declared as a class-name in the namespace that contains 4894 // the declaration; otherwise, except as a friend 4895 // declaration, the identifier is declared in the smallest 4896 // non-class, non-function-prototype scope that contains the 4897 // declaration. 4898 // 4899 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4900 // C structs and unions. 4901 // 4902 // It is an error in C++ to declare (rather than define) an enum 4903 // type, including via an elaborated type specifier. We'll 4904 // diagnose that later; for now, declare the enum in the same 4905 // scope as we would have picked for any other tag type. 4906 // 4907 // GNU C also supports this behavior as part of its incomplete 4908 // enum types extension, while GNU C++ does not. 4909 // 4910 // Find the context where we'll be declaring the tag. 4911 // FIXME: We would like to maintain the current DeclContext as the 4912 // lexical context, 4913 while (SearchDC->isRecord()) 4914 SearchDC = SearchDC->getParent(); 4915 4916 // Find the scope where we'll be declaring the tag. 4917 while (S->isClassScope() || 4918 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4919 ((S->getFlags() & Scope::DeclScope) == 0) || 4920 (S->getEntity() && 4921 ((DeclContext *)S->getEntity())->isTransparentContext())) 4922 S = S->getParent(); 4923 4924 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4925 // C++ [namespace.memdef]p3: 4926 // If a friend declaration in a non-local class first declares a 4927 // class or function, the friend class or function is a member of 4928 // the innermost enclosing namespace. 4929 while (!SearchDC->isFileContext()) 4930 SearchDC = SearchDC->getParent(); 4931 4932 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4933 while (S->getEntity() != SearchDC) 4934 S = S->getParent(); 4935 } 4936 4937CreateNewDecl: 4938 4939 TagDecl *PrevDecl = 0; 4940 if (Previous.isSingleResult()) 4941 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4942 4943 // If there is an identifier, use the location of the identifier as the 4944 // location of the decl, otherwise use the location of the struct/union 4945 // keyword. 4946 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4947 4948 // Otherwise, create a new declaration. If there is a previous 4949 // declaration of the same entity, the two will be linked via 4950 // PrevDecl. 4951 TagDecl *New; 4952 4953 if (Kind == TagDecl::TK_enum) { 4954 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4955 // enum X { A, B, C } D; D should chain to X. 4956 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4957 cast_or_null<EnumDecl>(PrevDecl)); 4958 // If this is an undefined enum, warn. 4959 if (TUK != TUK_Definition && !Invalid) { 4960 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4961 : diag::ext_forward_ref_enum; 4962 Diag(Loc, DK); 4963 } 4964 } else { 4965 // struct/union/class 4966 4967 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4968 // struct X { int A; } D; D should chain to X. 4969 if (getLangOptions().CPlusPlus) { 4970 // FIXME: Look for a way to use RecordDecl for simple structs. 4971 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4972 cast_or_null<CXXRecordDecl>(PrevDecl)); 4973 4974 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4975 StdBadAlloc = cast<CXXRecordDecl>(New); 4976 } else 4977 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4978 cast_or_null<RecordDecl>(PrevDecl)); 4979 } 4980 4981 if (Kind != TagDecl::TK_enum) { 4982 // Handle #pragma pack: if the #pragma pack stack has non-default 4983 // alignment, make up a packed attribute for this decl. These 4984 // attributes are checked when the ASTContext lays out the 4985 // structure. 4986 // 4987 // It is important for implementing the correct semantics that this 4988 // happen here (in act on tag decl). The #pragma pack stack is 4989 // maintained as a result of parser callbacks which can occur at 4990 // many points during the parsing of a struct declaration (because 4991 // the #pragma tokens are effectively skipped over during the 4992 // parsing of the struct). 4993 if (unsigned Alignment = getPragmaPackAlignment()) 4994 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4995 } 4996 4997 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4998 // C++ [dcl.typedef]p3: 4999 // [...] Similarly, in a given scope, a class or enumeration 5000 // shall not be declared with the same name as a typedef-name 5001 // that is declared in that scope and refers to a type other 5002 // than the class or enumeration itself. 5003 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5004 ForRedeclaration); 5005 LookupName(Lookup, S); 5006 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5007 NamedDecl *PrevTypedefNamed = PrevTypedef; 5008 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5009 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5010 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5011 Diag(Loc, diag::err_tag_definition_of_typedef) 5012 << Context.getTypeDeclType(New) 5013 << PrevTypedef->getUnderlyingType(); 5014 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5015 Invalid = true; 5016 } 5017 } 5018 5019 // If this is a specialization of a member class (of a class template), 5020 // check the specialization. 5021 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5022 Invalid = true; 5023 5024 if (Invalid) 5025 New->setInvalidDecl(); 5026 5027 if (Attr) 5028 ProcessDeclAttributeList(S, New, Attr); 5029 5030 // If we're declaring or defining a tag in function prototype scope 5031 // in C, note that this type can only be used within the function. 5032 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5033 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5034 5035 // Set the lexical context. If the tag has a C++ scope specifier, the 5036 // lexical context will be different from the semantic context. 5037 New->setLexicalDeclContext(CurContext); 5038 5039 // Mark this as a friend decl if applicable. 5040 if (TUK == TUK_Friend) 5041 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5042 5043 // Set the access specifier. 5044 if (!Invalid && TUK != TUK_Friend) 5045 SetMemberAccessSpecifier(New, PrevDecl, AS); 5046 5047 if (TUK == TUK_Definition) 5048 New->startDefinition(); 5049 5050 // If this has an identifier, add it to the scope stack. 5051 if (TUK == TUK_Friend) { 5052 // We might be replacing an existing declaration in the lookup tables; 5053 // if so, borrow its access specifier. 5054 if (PrevDecl) 5055 New->setAccess(PrevDecl->getAccess()); 5056 5057 // Friend tag decls are visible in fairly strange ways. 5058 if (!CurContext->isDependentContext()) { 5059 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5060 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5061 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5062 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5063 } 5064 } else if (Name) { 5065 S = getNonFieldDeclScope(S); 5066 PushOnScopeChains(New, S); 5067 } else { 5068 CurContext->addDecl(New); 5069 } 5070 5071 // If this is the C FILE type, notify the AST context. 5072 if (IdentifierInfo *II = New->getIdentifier()) 5073 if (!New->isInvalidDecl() && 5074 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5075 II->isStr("FILE")) 5076 Context.setFILEDecl(New); 5077 5078 OwnedDecl = true; 5079 return DeclPtrTy::make(New); 5080} 5081 5082void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5083 AdjustDeclIfTemplate(TagD); 5084 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5085 5086 // Enter the tag context. 5087 PushDeclContext(S, Tag); 5088} 5089 5090void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5091 SourceLocation LBraceLoc) { 5092 AdjustDeclIfTemplate(TagD); 5093 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5094 5095 FieldCollector->StartClass(); 5096 5097 if (!Record->getIdentifier()) 5098 return; 5099 5100 // C++ [class]p2: 5101 // [...] The class-name is also inserted into the scope of the 5102 // class itself; this is known as the injected-class-name. For 5103 // purposes of access checking, the injected-class-name is treated 5104 // as if it were a public member name. 5105 CXXRecordDecl *InjectedClassName 5106 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5107 CurContext, Record->getLocation(), 5108 Record->getIdentifier(), 5109 Record->getTagKeywordLoc(), 5110 Record); 5111 InjectedClassName->setImplicit(); 5112 InjectedClassName->setAccess(AS_public); 5113 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5114 InjectedClassName->setDescribedClassTemplate(Template); 5115 PushOnScopeChains(InjectedClassName, S); 5116 assert(InjectedClassName->isInjectedClassName() && 5117 "Broken injected-class-name"); 5118} 5119 5120// Traverses the class and any nested classes, making a note of any 5121// dynamic classes that have no key function so that we can mark all of 5122// their virtual member functions as "used" at the end of the translation 5123// unit. This ensures that all functions needed by the vtable will get 5124// instantiated/synthesized. 5125static void 5126RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5127 SourceLocation Loc) { 5128 // We don't look at dependent or undefined classes. 5129 if (Record->isDependentContext() || !Record->isDefinition()) 5130 return; 5131 5132 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 5133 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 5134 5135 for (DeclContext::decl_iterator D = Record->decls_begin(), 5136 DEnd = Record->decls_end(); 5137 D != DEnd; ++D) { 5138 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5139 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5140 } 5141} 5142 5143void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5144 SourceLocation RBraceLoc) { 5145 AdjustDeclIfTemplate(TagD); 5146 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5147 Tag->setRBraceLoc(RBraceLoc); 5148 5149 if (isa<CXXRecordDecl>(Tag)) 5150 FieldCollector->FinishClass(); 5151 5152 // Exit this scope of this tag's definition. 5153 PopDeclContext(); 5154 5155 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 5156 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5157 RBraceLoc); 5158 5159 // Notify the consumer that we've defined a tag. 5160 Consumer.HandleTagDeclDefinition(Tag); 5161} 5162 5163// Note that FieldName may be null for anonymous bitfields. 5164bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5165 QualType FieldTy, const Expr *BitWidth, 5166 bool *ZeroWidth) { 5167 // Default to true; that shouldn't confuse checks for emptiness 5168 if (ZeroWidth) 5169 *ZeroWidth = true; 5170 5171 // C99 6.7.2.1p4 - verify the field type. 5172 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5173 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5174 // Handle incomplete types with specific error. 5175 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5176 return true; 5177 if (FieldName) 5178 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5179 << FieldName << FieldTy << BitWidth->getSourceRange(); 5180 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5181 << FieldTy << BitWidth->getSourceRange(); 5182 } 5183 5184 // If the bit-width is type- or value-dependent, don't try to check 5185 // it now. 5186 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5187 return false; 5188 5189 llvm::APSInt Value; 5190 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5191 return true; 5192 5193 if (Value != 0 && ZeroWidth) 5194 *ZeroWidth = false; 5195 5196 // Zero-width bitfield is ok for anonymous field. 5197 if (Value == 0 && FieldName) 5198 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5199 5200 if (Value.isSigned() && Value.isNegative()) { 5201 if (FieldName) 5202 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5203 << FieldName << Value.toString(10); 5204 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5205 << Value.toString(10); 5206 } 5207 5208 if (!FieldTy->isDependentType()) { 5209 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5210 if (Value.getZExtValue() > TypeSize) { 5211 if (FieldName) 5212 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5213 << FieldName << (unsigned)TypeSize; 5214 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5215 << (unsigned)TypeSize; 5216 } 5217 } 5218 5219 return false; 5220} 5221 5222/// ActOnField - Each field of a struct/union/class is passed into this in order 5223/// to create a FieldDecl object for it. 5224Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5225 SourceLocation DeclStart, 5226 Declarator &D, ExprTy *BitfieldWidth) { 5227 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5228 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5229 AS_public); 5230 return DeclPtrTy::make(Res); 5231} 5232 5233/// HandleField - Analyze a field of a C struct or a C++ data member. 5234/// 5235FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5236 SourceLocation DeclStart, 5237 Declarator &D, Expr *BitWidth, 5238 AccessSpecifier AS) { 5239 IdentifierInfo *II = D.getIdentifier(); 5240 SourceLocation Loc = DeclStart; 5241 if (II) Loc = D.getIdentifierLoc(); 5242 5243 TypeSourceInfo *TInfo = 0; 5244 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5245 if (getLangOptions().CPlusPlus) 5246 CheckExtraCXXDefaultArguments(D); 5247 5248 DiagnoseFunctionSpecifiers(D); 5249 5250 if (D.getDeclSpec().isThreadSpecified()) 5251 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5252 5253 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5254 ForRedeclaration); 5255 5256 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5257 // Maybe we will complain about the shadowed template parameter. 5258 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5259 // Just pretend that we didn't see the previous declaration. 5260 PrevDecl = 0; 5261 } 5262 5263 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5264 PrevDecl = 0; 5265 5266 bool Mutable 5267 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5268 SourceLocation TSSL = D.getSourceRange().getBegin(); 5269 FieldDecl *NewFD 5270 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5271 AS, PrevDecl, &D); 5272 if (NewFD->isInvalidDecl() && PrevDecl) { 5273 // Don't introduce NewFD into scope; there's already something 5274 // with the same name in the same scope. 5275 } else if (II) { 5276 PushOnScopeChains(NewFD, S); 5277 } else 5278 Record->addDecl(NewFD); 5279 5280 return NewFD; 5281} 5282 5283/// \brief Build a new FieldDecl and check its well-formedness. 5284/// 5285/// This routine builds a new FieldDecl given the fields name, type, 5286/// record, etc. \p PrevDecl should refer to any previous declaration 5287/// with the same name and in the same scope as the field to be 5288/// created. 5289/// 5290/// \returns a new FieldDecl. 5291/// 5292/// \todo The Declarator argument is a hack. It will be removed once 5293FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5294 TypeSourceInfo *TInfo, 5295 RecordDecl *Record, SourceLocation Loc, 5296 bool Mutable, Expr *BitWidth, 5297 SourceLocation TSSL, 5298 AccessSpecifier AS, NamedDecl *PrevDecl, 5299 Declarator *D) { 5300 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5301 bool InvalidDecl = false; 5302 if (D) InvalidDecl = D->isInvalidType(); 5303 5304 // If we receive a broken type, recover by assuming 'int' and 5305 // marking this declaration as invalid. 5306 if (T.isNull()) { 5307 InvalidDecl = true; 5308 T = Context.IntTy; 5309 } 5310 5311 QualType EltTy = Context.getBaseElementType(T); 5312 if (!EltTy->isDependentType() && 5313 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5314 InvalidDecl = true; 5315 5316 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5317 // than a variably modified type. 5318 if (!InvalidDecl && T->isVariablyModifiedType()) { 5319 bool SizeIsNegative; 5320 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5321 SizeIsNegative); 5322 if (!FixedTy.isNull()) { 5323 Diag(Loc, diag::warn_illegal_constant_array_size); 5324 T = FixedTy; 5325 } else { 5326 if (SizeIsNegative) 5327 Diag(Loc, diag::err_typecheck_negative_array_size); 5328 else 5329 Diag(Loc, diag::err_typecheck_field_variable_size); 5330 InvalidDecl = true; 5331 } 5332 } 5333 5334 // Fields can not have abstract class types 5335 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5336 diag::err_abstract_type_in_decl, 5337 AbstractFieldType)) 5338 InvalidDecl = true; 5339 5340 bool ZeroWidth = false; 5341 // If this is declared as a bit-field, check the bit-field. 5342 if (!InvalidDecl && BitWidth && 5343 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5344 InvalidDecl = true; 5345 DeleteExpr(BitWidth); 5346 BitWidth = 0; 5347 ZeroWidth = false; 5348 } 5349 5350 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5351 BitWidth, Mutable); 5352 if (InvalidDecl) 5353 NewFD->setInvalidDecl(); 5354 5355 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5356 Diag(Loc, diag::err_duplicate_member) << II; 5357 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5358 NewFD->setInvalidDecl(); 5359 } 5360 5361 if (getLangOptions().CPlusPlus) { 5362 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5363 5364 if (!T->isPODType()) 5365 CXXRecord->setPOD(false); 5366 if (!ZeroWidth) 5367 CXXRecord->setEmpty(false); 5368 5369 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5370 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5371 5372 if (!RDecl->hasTrivialConstructor()) 5373 CXXRecord->setHasTrivialConstructor(false); 5374 if (!RDecl->hasTrivialCopyConstructor()) 5375 CXXRecord->setHasTrivialCopyConstructor(false); 5376 if (!RDecl->hasTrivialCopyAssignment()) 5377 CXXRecord->setHasTrivialCopyAssignment(false); 5378 if (!RDecl->hasTrivialDestructor()) 5379 CXXRecord->setHasTrivialDestructor(false); 5380 5381 // C++ 9.5p1: An object of a class with a non-trivial 5382 // constructor, a non-trivial copy constructor, a non-trivial 5383 // destructor, or a non-trivial copy assignment operator 5384 // cannot be a member of a union, nor can an array of such 5385 // objects. 5386 // TODO: C++0x alters this restriction significantly. 5387 if (Record->isUnion()) { 5388 // We check for copy constructors before constructors 5389 // because otherwise we'll never get complaints about 5390 // copy constructors. 5391 5392 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5393 5394 CXXSpecialMember member; 5395 if (!RDecl->hasTrivialCopyConstructor()) 5396 member = CXXCopyConstructor; 5397 else if (!RDecl->hasTrivialConstructor()) 5398 member = CXXDefaultConstructor; 5399 else if (!RDecl->hasTrivialCopyAssignment()) 5400 member = CXXCopyAssignment; 5401 else if (!RDecl->hasTrivialDestructor()) 5402 member = CXXDestructor; 5403 else 5404 member = invalid; 5405 5406 if (member != invalid) { 5407 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5408 DiagnoseNontrivial(RT, member); 5409 NewFD->setInvalidDecl(); 5410 } 5411 } 5412 } 5413 } 5414 5415 // FIXME: We need to pass in the attributes given an AST 5416 // representation, not a parser representation. 5417 if (D) 5418 // FIXME: What to pass instead of TUScope? 5419 ProcessDeclAttributes(TUScope, NewFD, *D); 5420 5421 if (T.isObjCGCWeak()) 5422 Diag(Loc, diag::warn_attribute_weak_on_field); 5423 5424 NewFD->setAccess(AS); 5425 5426 // C++ [dcl.init.aggr]p1: 5427 // An aggregate is an array or a class (clause 9) with [...] no 5428 // private or protected non-static data members (clause 11). 5429 // A POD must be an aggregate. 5430 if (getLangOptions().CPlusPlus && 5431 (AS == AS_private || AS == AS_protected)) { 5432 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5433 CXXRecord->setAggregate(false); 5434 CXXRecord->setPOD(false); 5435 } 5436 5437 return NewFD; 5438} 5439 5440/// DiagnoseNontrivial - Given that a class has a non-trivial 5441/// special member, figure out why. 5442void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5443 QualType QT(T, 0U); 5444 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5445 5446 // Check whether the member was user-declared. 5447 switch (member) { 5448 case CXXDefaultConstructor: 5449 if (RD->hasUserDeclaredConstructor()) { 5450 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5451 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5452 const FunctionDecl *body = 0; 5453 ci->getBody(body); 5454 if (!body || 5455 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5456 SourceLocation CtorLoc = ci->getLocation(); 5457 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5458 return; 5459 } 5460 } 5461 5462 assert(0 && "found no user-declared constructors"); 5463 return; 5464 } 5465 break; 5466 5467 case CXXCopyConstructor: 5468 if (RD->hasUserDeclaredCopyConstructor()) { 5469 SourceLocation CtorLoc = 5470 RD->getCopyConstructor(Context, 0)->getLocation(); 5471 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5472 return; 5473 } 5474 break; 5475 5476 case CXXCopyAssignment: 5477 if (RD->hasUserDeclaredCopyAssignment()) { 5478 // FIXME: this should use the location of the copy 5479 // assignment, not the type. 5480 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5481 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5482 return; 5483 } 5484 break; 5485 5486 case CXXDestructor: 5487 if (RD->hasUserDeclaredDestructor()) { 5488 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5489 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5490 return; 5491 } 5492 break; 5493 } 5494 5495 typedef CXXRecordDecl::base_class_iterator base_iter; 5496 5497 // Virtual bases and members inhibit trivial copying/construction, 5498 // but not trivial destruction. 5499 if (member != CXXDestructor) { 5500 // Check for virtual bases. vbases includes indirect virtual bases, 5501 // so we just iterate through the direct bases. 5502 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5503 if (bi->isVirtual()) { 5504 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5505 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5506 return; 5507 } 5508 5509 // Check for virtual methods. 5510 typedef CXXRecordDecl::method_iterator meth_iter; 5511 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5512 ++mi) { 5513 if (mi->isVirtual()) { 5514 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5515 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5516 return; 5517 } 5518 } 5519 } 5520 5521 bool (CXXRecordDecl::*hasTrivial)() const; 5522 switch (member) { 5523 case CXXDefaultConstructor: 5524 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5525 case CXXCopyConstructor: 5526 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5527 case CXXCopyAssignment: 5528 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5529 case CXXDestructor: 5530 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5531 default: 5532 assert(0 && "unexpected special member"); return; 5533 } 5534 5535 // Check for nontrivial bases (and recurse). 5536 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5537 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5538 assert(BaseRT && "Don't know how to handle dependent bases"); 5539 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5540 if (!(BaseRecTy->*hasTrivial)()) { 5541 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5542 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5543 DiagnoseNontrivial(BaseRT, member); 5544 return; 5545 } 5546 } 5547 5548 // Check for nontrivial members (and recurse). 5549 typedef RecordDecl::field_iterator field_iter; 5550 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5551 ++fi) { 5552 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5553 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5554 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5555 5556 if (!(EltRD->*hasTrivial)()) { 5557 SourceLocation FLoc = (*fi)->getLocation(); 5558 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5559 DiagnoseNontrivial(EltRT, member); 5560 return; 5561 } 5562 } 5563 } 5564 5565 assert(0 && "found no explanation for non-trivial member"); 5566} 5567 5568/// TranslateIvarVisibility - Translate visibility from a token ID to an 5569/// AST enum value. 5570static ObjCIvarDecl::AccessControl 5571TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5572 switch (ivarVisibility) { 5573 default: assert(0 && "Unknown visitibility kind"); 5574 case tok::objc_private: return ObjCIvarDecl::Private; 5575 case tok::objc_public: return ObjCIvarDecl::Public; 5576 case tok::objc_protected: return ObjCIvarDecl::Protected; 5577 case tok::objc_package: return ObjCIvarDecl::Package; 5578 } 5579} 5580 5581/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5582/// in order to create an IvarDecl object for it. 5583Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5584 SourceLocation DeclStart, 5585 DeclPtrTy IntfDecl, 5586 Declarator &D, ExprTy *BitfieldWidth, 5587 tok::ObjCKeywordKind Visibility) { 5588 5589 IdentifierInfo *II = D.getIdentifier(); 5590 Expr *BitWidth = (Expr*)BitfieldWidth; 5591 SourceLocation Loc = DeclStart; 5592 if (II) Loc = D.getIdentifierLoc(); 5593 5594 // FIXME: Unnamed fields can be handled in various different ways, for 5595 // example, unnamed unions inject all members into the struct namespace! 5596 5597 TypeSourceInfo *TInfo = 0; 5598 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5599 5600 if (BitWidth) { 5601 // 6.7.2.1p3, 6.7.2.1p4 5602 if (VerifyBitField(Loc, II, T, BitWidth)) { 5603 D.setInvalidType(); 5604 DeleteExpr(BitWidth); 5605 BitWidth = 0; 5606 } 5607 } else { 5608 // Not a bitfield. 5609 5610 // validate II. 5611 5612 } 5613 5614 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5615 // than a variably modified type. 5616 if (T->isVariablyModifiedType()) { 5617 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5618 D.setInvalidType(); 5619 } 5620 5621 // Get the visibility (access control) for this ivar. 5622 ObjCIvarDecl::AccessControl ac = 5623 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5624 : ObjCIvarDecl::None; 5625 // Must set ivar's DeclContext to its enclosing interface. 5626 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5627 DeclContext *EnclosingContext; 5628 if (ObjCImplementationDecl *IMPDecl = 5629 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5630 // Case of ivar declared in an implementation. Context is that of its class. 5631 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5632 assert(IDecl && "No class- ActOnIvar"); 5633 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5634 } else 5635 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5636 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5637 5638 // Construct the decl. 5639 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5640 EnclosingContext, Loc, II, T, 5641 TInfo, ac, (Expr *)BitfieldWidth); 5642 5643 if (II) { 5644 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5645 ForRedeclaration); 5646 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5647 && !isa<TagDecl>(PrevDecl)) { 5648 Diag(Loc, diag::err_duplicate_member) << II; 5649 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5650 NewID->setInvalidDecl(); 5651 } 5652 } 5653 5654 // Process attributes attached to the ivar. 5655 ProcessDeclAttributes(S, NewID, D); 5656 5657 if (D.isInvalidType()) 5658 NewID->setInvalidDecl(); 5659 5660 if (II) { 5661 // FIXME: When interfaces are DeclContexts, we'll need to add 5662 // these to the interface. 5663 S->AddDecl(DeclPtrTy::make(NewID)); 5664 IdResolver.AddDecl(NewID); 5665 } 5666 5667 return DeclPtrTy::make(NewID); 5668} 5669 5670void Sema::ActOnFields(Scope* S, 5671 SourceLocation RecLoc, DeclPtrTy RecDecl, 5672 DeclPtrTy *Fields, unsigned NumFields, 5673 SourceLocation LBrac, SourceLocation RBrac, 5674 AttributeList *Attr) { 5675 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5676 assert(EnclosingDecl && "missing record or interface decl"); 5677 5678 // If the decl this is being inserted into is invalid, then it may be a 5679 // redeclaration or some other bogus case. Don't try to add fields to it. 5680 if (EnclosingDecl->isInvalidDecl()) { 5681 // FIXME: Deallocate fields? 5682 return; 5683 } 5684 5685 5686 // Verify that all the fields are okay. 5687 unsigned NumNamedMembers = 0; 5688 llvm::SmallVector<FieldDecl*, 32> RecFields; 5689 5690 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5691 for (unsigned i = 0; i != NumFields; ++i) { 5692 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5693 5694 // Get the type for the field. 5695 Type *FDTy = FD->getType().getTypePtr(); 5696 5697 if (!FD->isAnonymousStructOrUnion()) { 5698 // Remember all fields written by the user. 5699 RecFields.push_back(FD); 5700 } 5701 5702 // If the field is already invalid for some reason, don't emit more 5703 // diagnostics about it. 5704 if (FD->isInvalidDecl()) { 5705 EnclosingDecl->setInvalidDecl(); 5706 continue; 5707 } 5708 5709 // C99 6.7.2.1p2: 5710 // A structure or union shall not contain a member with 5711 // incomplete or function type (hence, a structure shall not 5712 // contain an instance of itself, but may contain a pointer to 5713 // an instance of itself), except that the last member of a 5714 // structure with more than one named member may have incomplete 5715 // array type; such a structure (and any union containing, 5716 // possibly recursively, a member that is such a structure) 5717 // shall not be a member of a structure or an element of an 5718 // array. 5719 if (FDTy->isFunctionType()) { 5720 // Field declared as a function. 5721 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5722 << FD->getDeclName(); 5723 FD->setInvalidDecl(); 5724 EnclosingDecl->setInvalidDecl(); 5725 continue; 5726 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5727 Record && Record->isStruct()) { 5728 // Flexible array member. 5729 if (NumNamedMembers < 1) { 5730 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5731 << FD->getDeclName(); 5732 FD->setInvalidDecl(); 5733 EnclosingDecl->setInvalidDecl(); 5734 continue; 5735 } 5736 // Okay, we have a legal flexible array member at the end of the struct. 5737 if (Record) 5738 Record->setHasFlexibleArrayMember(true); 5739 } else if (!FDTy->isDependentType() && 5740 RequireCompleteType(FD->getLocation(), FD->getType(), 5741 diag::err_field_incomplete)) { 5742 // Incomplete type 5743 FD->setInvalidDecl(); 5744 EnclosingDecl->setInvalidDecl(); 5745 continue; 5746 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5747 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5748 // If this is a member of a union, then entire union becomes "flexible". 5749 if (Record && Record->isUnion()) { 5750 Record->setHasFlexibleArrayMember(true); 5751 } else { 5752 // If this is a struct/class and this is not the last element, reject 5753 // it. Note that GCC supports variable sized arrays in the middle of 5754 // structures. 5755 if (i != NumFields-1) 5756 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5757 << FD->getDeclName() << FD->getType(); 5758 else { 5759 // We support flexible arrays at the end of structs in 5760 // other structs as an extension. 5761 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5762 << FD->getDeclName(); 5763 if (Record) 5764 Record->setHasFlexibleArrayMember(true); 5765 } 5766 } 5767 } 5768 if (Record && FDTTy->getDecl()->hasObjectMember()) 5769 Record->setHasObjectMember(true); 5770 } else if (FDTy->isObjCInterfaceType()) { 5771 /// A field cannot be an Objective-c object 5772 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5773 FD->setInvalidDecl(); 5774 EnclosingDecl->setInvalidDecl(); 5775 continue; 5776 } else if (getLangOptions().ObjC1 && 5777 getLangOptions().getGCMode() != LangOptions::NonGC && 5778 Record && 5779 (FD->getType()->isObjCObjectPointerType() || 5780 FD->getType().isObjCGCStrong())) 5781 Record->setHasObjectMember(true); 5782 // Keep track of the number of named members. 5783 if (FD->getIdentifier()) 5784 ++NumNamedMembers; 5785 } 5786 5787 // Okay, we successfully defined 'Record'. 5788 if (Record) { 5789 Record->completeDefinition(Context); 5790 } else { 5791 ObjCIvarDecl **ClsFields = 5792 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5793 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5794 ID->setIVarList(ClsFields, RecFields.size(), Context); 5795 ID->setLocEnd(RBrac); 5796 // Add ivar's to class's DeclContext. 5797 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5798 ClsFields[i]->setLexicalDeclContext(ID); 5799 ID->addDecl(ClsFields[i]); 5800 } 5801 // Must enforce the rule that ivars in the base classes may not be 5802 // duplicates. 5803 if (ID->getSuperClass()) { 5804 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5805 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5806 ObjCIvarDecl* Ivar = (*IVI); 5807 5808 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5809 ObjCIvarDecl* prevIvar = 5810 ID->getSuperClass()->lookupInstanceVariable(II); 5811 if (prevIvar) { 5812 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5813 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5814 } 5815 } 5816 } 5817 } 5818 } else if (ObjCImplementationDecl *IMPDecl = 5819 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5820 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5821 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5822 // Ivar declared in @implementation never belongs to the implementation. 5823 // Only it is in implementation's lexical context. 5824 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5825 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5826 } 5827 } 5828 5829 if (Attr) 5830 ProcessDeclAttributeList(S, Record, Attr); 5831} 5832 5833EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5834 EnumConstantDecl *LastEnumConst, 5835 SourceLocation IdLoc, 5836 IdentifierInfo *Id, 5837 ExprArg val) { 5838 Expr *Val = (Expr *)val.get(); 5839 5840 llvm::APSInt EnumVal(32); 5841 QualType EltTy; 5842 if (Val) { 5843 if (Enum->isDependentType()) 5844 EltTy = Context.DependentTy; 5845 else { 5846 // Make sure to promote the operand type to int. 5847 UsualUnaryConversions(Val); 5848 if (Val != val.get()) { 5849 val.release(); 5850 val = Val; 5851 } 5852 5853 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5854 SourceLocation ExpLoc; 5855 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5856 Val = 0; 5857 } else { 5858 EltTy = Val->getType(); 5859 } 5860 } 5861 } 5862 5863 if (!Val) { 5864 if (Enum->isDependentType()) 5865 EltTy = Context.DependentTy; 5866 else if (LastEnumConst) { 5867 // Assign the last value + 1. 5868 EnumVal = LastEnumConst->getInitVal(); 5869 ++EnumVal; 5870 5871 // Check for overflow on increment. 5872 if (EnumVal < LastEnumConst->getInitVal()) 5873 Diag(IdLoc, diag::warn_enum_value_overflow); 5874 5875 EltTy = LastEnumConst->getType(); 5876 } else { 5877 // First value, set to zero. 5878 EltTy = Context.IntTy; 5879 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5880 EnumVal.setIsSigned(true); 5881 } 5882 } 5883 5884 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5885 5886 val.release(); 5887 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5888 Val, EnumVal); 5889} 5890 5891 5892Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5893 DeclPtrTy lastEnumConst, 5894 SourceLocation IdLoc, 5895 IdentifierInfo *Id, 5896 SourceLocation EqualLoc, ExprTy *val) { 5897 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5898 EnumConstantDecl *LastEnumConst = 5899 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5900 Expr *Val = static_cast<Expr*>(val); 5901 5902 // The scope passed in may not be a decl scope. Zip up the scope tree until 5903 // we find one that is. 5904 S = getNonFieldDeclScope(S); 5905 5906 // Verify that there isn't already something declared with this name in this 5907 // scope. 5908 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5909 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5910 // Maybe we will complain about the shadowed template parameter. 5911 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5912 // Just pretend that we didn't see the previous declaration. 5913 PrevDecl = 0; 5914 } 5915 5916 if (PrevDecl) { 5917 // When in C++, we may get a TagDecl with the same name; in this case the 5918 // enum constant will 'hide' the tag. 5919 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5920 "Received TagDecl when not in C++!"); 5921 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5922 if (isa<EnumConstantDecl>(PrevDecl)) 5923 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5924 else 5925 Diag(IdLoc, diag::err_redefinition) << Id; 5926 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5927 if (Val) Val->Destroy(Context); 5928 return DeclPtrTy(); 5929 } 5930 } 5931 5932 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5933 IdLoc, Id, Owned(Val)); 5934 5935 // Register this decl in the current scope stack. 5936 if (New) 5937 PushOnScopeChains(New, S); 5938 5939 return DeclPtrTy::make(New); 5940} 5941 5942void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5943 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5944 DeclPtrTy *Elements, unsigned NumElements, 5945 Scope *S, AttributeList *Attr) { 5946 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5947 QualType EnumType = Context.getTypeDeclType(Enum); 5948 5949 if (Attr) 5950 ProcessDeclAttributeList(S, Enum, Attr); 5951 5952 if (Enum->isDependentType()) { 5953 for (unsigned i = 0; i != NumElements; ++i) { 5954 EnumConstantDecl *ECD = 5955 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5956 if (!ECD) continue; 5957 5958 ECD->setType(EnumType); 5959 } 5960 5961 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 5962 return; 5963 } 5964 5965 // TODO: If the result value doesn't fit in an int, it must be a long or long 5966 // long value. ISO C does not support this, but GCC does as an extension, 5967 // emit a warning. 5968 unsigned IntWidth = Context.Target.getIntWidth(); 5969 unsigned CharWidth = Context.Target.getCharWidth(); 5970 unsigned ShortWidth = Context.Target.getShortWidth(); 5971 5972 // Verify that all the values are okay, compute the size of the values, and 5973 // reverse the list. 5974 unsigned NumNegativeBits = 0; 5975 unsigned NumPositiveBits = 0; 5976 5977 // Keep track of whether all elements have type int. 5978 bool AllElementsInt = true; 5979 5980 for (unsigned i = 0; i != NumElements; ++i) { 5981 EnumConstantDecl *ECD = 5982 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5983 if (!ECD) continue; // Already issued a diagnostic. 5984 5985 // If the enum value doesn't fit in an int, emit an extension warning. 5986 const llvm::APSInt &InitVal = ECD->getInitVal(); 5987 assert(InitVal.getBitWidth() >= IntWidth && 5988 "Should have promoted value to int"); 5989 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 5990 llvm::APSInt V(InitVal); 5991 V.trunc(IntWidth); 5992 V.extend(InitVal.getBitWidth()); 5993 if (V != InitVal) 5994 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5995 << InitVal.toString(10); 5996 } 5997 5998 // Keep track of the size of positive and negative values. 5999 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6000 NumPositiveBits = std::max(NumPositiveBits, 6001 (unsigned)InitVal.getActiveBits()); 6002 else 6003 NumNegativeBits = std::max(NumNegativeBits, 6004 (unsigned)InitVal.getMinSignedBits()); 6005 6006 // Keep track of whether every enum element has type int (very commmon). 6007 if (AllElementsInt) 6008 AllElementsInt = ECD->getType() == Context.IntTy; 6009 } 6010 6011 // Figure out the type that should be used for this enum. 6012 // FIXME: Support -fshort-enums. 6013 QualType BestType; 6014 unsigned BestWidth; 6015 6016 // C++0x N3000 [conv.prom]p3: 6017 // An rvalue of an unscoped enumeration type whose underlying 6018 // type is not fixed can be converted to an rvalue of the first 6019 // of the following types that can represent all the values of 6020 // the enumeration: int, unsigned int, long int, unsigned long 6021 // int, long long int, or unsigned long long int. 6022 // C99 6.4.4.3p2: 6023 // An identifier declared as an enumeration constant has type int. 6024 // The C99 rule is modified by a gcc extension 6025 QualType BestPromotionType; 6026 6027 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6028 6029 if (NumNegativeBits) { 6030 // If there is a negative value, figure out the smallest integer type (of 6031 // int/long/longlong) that fits. 6032 // If it's packed, check also if it fits a char or a short. 6033 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6034 BestType = Context.SignedCharTy; 6035 BestWidth = CharWidth; 6036 } else if (Packed && NumNegativeBits <= ShortWidth && 6037 NumPositiveBits < ShortWidth) { 6038 BestType = Context.ShortTy; 6039 BestWidth = ShortWidth; 6040 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6041 BestType = Context.IntTy; 6042 BestWidth = IntWidth; 6043 } else { 6044 BestWidth = Context.Target.getLongWidth(); 6045 6046 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6047 BestType = Context.LongTy; 6048 } else { 6049 BestWidth = Context.Target.getLongLongWidth(); 6050 6051 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6052 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6053 BestType = Context.LongLongTy; 6054 } 6055 } 6056 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6057 } else { 6058 // If there is no negative value, figure out which of uint, ulong, ulonglong 6059 // fits. 6060 // If it's packed, check also if it fits a char or a short. 6061 if (Packed && NumPositiveBits <= CharWidth) { 6062 BestType = Context.UnsignedCharTy; 6063 BestPromotionType = Context.IntTy; 6064 BestWidth = CharWidth; 6065 } else if (Packed && NumPositiveBits <= ShortWidth) { 6066 BestType = Context.UnsignedShortTy; 6067 BestPromotionType = Context.IntTy; 6068 BestWidth = ShortWidth; 6069 } else if (NumPositiveBits <= IntWidth) { 6070 BestType = Context.UnsignedIntTy; 6071 BestWidth = IntWidth; 6072 BestPromotionType = (NumPositiveBits == BestWidth 6073 ? Context.UnsignedIntTy : Context.IntTy); 6074 } else if (NumPositiveBits <= 6075 (BestWidth = Context.Target.getLongWidth())) { 6076 BestType = Context.UnsignedLongTy; 6077 BestPromotionType = (NumPositiveBits == BestWidth 6078 ? Context.UnsignedLongTy : Context.LongTy); 6079 } else { 6080 BestWidth = Context.Target.getLongLongWidth(); 6081 assert(NumPositiveBits <= BestWidth && 6082 "How could an initializer get larger than ULL?"); 6083 BestType = Context.UnsignedLongLongTy; 6084 BestPromotionType = (NumPositiveBits == BestWidth 6085 ? Context.UnsignedLongLongTy : Context.LongLongTy); 6086 } 6087 } 6088 6089 // If we're in C and the promotion type is larger than an int, just 6090 // use the underlying type, which is generally the unsigned integer 6091 // type of the same rank as the promotion type. This is how the gcc 6092 // extension works. 6093 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 6094 BestPromotionType = BestType; 6095 6096 // Loop over all of the enumerator constants, changing their types to match 6097 // the type of the enum if needed. 6098 for (unsigned i = 0; i != NumElements; ++i) { 6099 EnumConstantDecl *ECD = 6100 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6101 if (!ECD) continue; // Already issued a diagnostic. 6102 6103 // Standard C says the enumerators have int type, but we allow, as an 6104 // extension, the enumerators to be larger than int size. If each 6105 // enumerator value fits in an int, type it as an int, otherwise type it the 6106 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6107 // that X has type 'int', not 'unsigned'. 6108 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 6109 continue; 6110 6111 // Determine whether the value fits into an int. 6112 llvm::APSInt InitVal = ECD->getInitVal(); 6113 bool FitsInInt; 6114 if (InitVal.isUnsigned() || !InitVal.isNegative()) 6115 FitsInInt = InitVal.getActiveBits() < IntWidth; 6116 else 6117 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 6118 6119 // If it fits into an integer type, force it. Otherwise force it to match 6120 // the enum decl type. 6121 QualType NewTy; 6122 unsigned NewWidth; 6123 bool NewSign; 6124 if (FitsInInt && !getLangOptions().CPlusPlus) { 6125 NewTy = Context.IntTy; 6126 NewWidth = IntWidth; 6127 NewSign = true; 6128 } else if (ECD->getType() == BestType) { 6129 // Already the right type! 6130 if (getLangOptions().CPlusPlus) 6131 // C++ [dcl.enum]p4: Following the closing brace of an 6132 // enum-specifier, each enumerator has the type of its 6133 // enumeration. 6134 ECD->setType(EnumType); 6135 continue; 6136 } else { 6137 NewTy = BestType; 6138 NewWidth = BestWidth; 6139 NewSign = BestType->isSignedIntegerType(); 6140 } 6141 6142 // Adjust the APSInt value. 6143 InitVal.extOrTrunc(NewWidth); 6144 InitVal.setIsSigned(NewSign); 6145 ECD->setInitVal(InitVal); 6146 6147 // Adjust the Expr initializer and type. 6148 if (ECD->getInitExpr()) 6149 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6150 CastExpr::CK_IntegralCast, 6151 ECD->getInitExpr(), 6152 /*isLvalue=*/false)); 6153 if (getLangOptions().CPlusPlus) 6154 // C++ [dcl.enum]p4: Following the closing brace of an 6155 // enum-specifier, each enumerator has the type of its 6156 // enumeration. 6157 ECD->setType(EnumType); 6158 else 6159 ECD->setType(NewTy); 6160 } 6161 6162 Enum->completeDefinition(Context, BestType, BestPromotionType); 6163} 6164 6165Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6166 ExprArg expr) { 6167 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6168 6169 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6170 Loc, AsmString); 6171 CurContext->addDecl(New); 6172 return DeclPtrTy::make(New); 6173} 6174 6175void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6176 SourceLocation PragmaLoc, 6177 SourceLocation NameLoc) { 6178 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6179 6180 if (PrevDecl) { 6181 PrevDecl->addAttr(::new (Context) WeakAttr()); 6182 } else { 6183 (void)WeakUndeclaredIdentifiers.insert( 6184 std::pair<IdentifierInfo*,WeakInfo> 6185 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6186 } 6187} 6188 6189void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6190 IdentifierInfo* AliasName, 6191 SourceLocation PragmaLoc, 6192 SourceLocation NameLoc, 6193 SourceLocation AliasNameLoc) { 6194 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6195 WeakInfo W = WeakInfo(Name, NameLoc); 6196 6197 if (PrevDecl) { 6198 if (!PrevDecl->hasAttr<AliasAttr>()) 6199 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6200 DeclApplyPragmaWeak(TUScope, ND, W); 6201 } else { 6202 (void)WeakUndeclaredIdentifiers.insert( 6203 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6204 } 6205} 6206