SemaDecl.cpp revision b0cb022daec8671406ab25f4b5d5a6d48d823bc4
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/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isSet()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, so build a 91 // TypenameType node to describe the type. 92 // FIXME: Record somewhere that this TypenameType node has no "typename" 93 // keyword associated with it. 94 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 95 II, SS->getRange()).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 102 return 0; 103 } 104 105 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 106 // lookup for class-names. 107 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 108 LookupOrdinaryName; 109 LookupResult Result(*this, &II, NameLoc, Kind); 110 if (LookupCtx) { 111 // Perform "qualified" name lookup into the declaration context we 112 // computed, which is either the type of the base of a member access 113 // expression or the declaration context associated with a prior 114 // nested-name-specifier. 115 LookupQualifiedName(Result, LookupCtx); 116 117 if (ObjectTypePtr && Result.empty()) { 118 // C++ [basic.lookup.classref]p3: 119 // If the unqualified-id is ~type-name, the type-name is looked up 120 // in the context of the entire postfix-expression. If the type T of 121 // the object expression is of a class type C, the type-name is also 122 // looked up in the scope of class C. At least one of the lookups shall 123 // find a name that refers to (possibly cv-qualified) T. 124 LookupName(Result, S); 125 } 126 } else { 127 // Perform unqualified name lookup. 128 LookupName(Result, S); 129 } 130 131 NamedDecl *IIDecl = 0; 132 switch (Result.getResultKind()) { 133 case LookupResult::NotFound: 134 case LookupResult::NotFoundInCurrentInstantiation: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 Result.suppressDiagnostics(); 138 return 0; 139 140 case LookupResult::Ambiguous: 141 // Recover from type-hiding ambiguities by hiding the type. We'll 142 // do the lookup again when looking for an object, and we can 143 // diagnose the error then. If we don't do this, then the error 144 // about hiding the type will be immediately followed by an error 145 // that only makes sense if the identifier was treated like a type. 146 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 147 Result.suppressDiagnostics(); 148 return 0; 149 } 150 151 // Look to see if we have a type anywhere in the list of results. 152 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 153 Res != ResEnd; ++Res) { 154 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 155 if (!IIDecl || 156 (*Res)->getLocation().getRawEncoding() < 157 IIDecl->getLocation().getRawEncoding()) 158 IIDecl = *Res; 159 } 160 } 161 162 if (!IIDecl) { 163 // None of the entities we found is a type, so there is no way 164 // to even assume that the result is a type. In this case, don't 165 // complain about the ambiguity. The parser will either try to 166 // perform this lookup again (e.g., as an object name), which 167 // will produce the ambiguity, or will complain that it expected 168 // a type name. 169 Result.suppressDiagnostics(); 170 return 0; 171 } 172 173 // We found a type within the ambiguous lookup; diagnose the 174 // ambiguity and then return that type. This might be the right 175 // answer, or it might not be, but it suppresses any attempt to 176 // perform the name lookup again. 177 break; 178 179 case LookupResult::Found: 180 IIDecl = Result.getFoundDecl(); 181 break; 182 } 183 184 assert(IIDecl && "Didn't find decl"); 185 186 QualType T; 187 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 188 DiagnoseUseOfDecl(IIDecl, NameLoc); 189 190 if (T.isNull()) 191 T = Context.getTypeDeclType(TD); 192 193 if (SS) 194 T = getQualifiedNameType(*SS, T); 195 196 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 197 T = Context.getObjCInterfaceType(IDecl); 198 } else if (UnresolvedUsingTypenameDecl *UUDecl = 199 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 200 // FIXME: preserve source structure information. 201 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 202 } else { 203 // If it's not plausibly a type, suppress diagnostics. 204 Result.suppressDiagnostics(); 205 return 0; 206 } 207 208 return T.getAsOpaquePtr(); 209} 210 211/// isTagName() - This method is called *for error recovery purposes only* 212/// to determine if the specified name is a valid tag name ("struct foo"). If 213/// so, this returns the TST for the tag corresponding to it (TST_enum, 214/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 215/// where the user forgot to specify the tag. 216DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 217 // Do a tag name lookup in this scope. 218 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 219 LookupName(R, S, false); 220 R.suppressDiagnostics(); 221 if (R.getResultKind() == LookupResult::Found) 222 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 223 switch (TD->getTagKind()) { 224 case TagDecl::TK_struct: return DeclSpec::TST_struct; 225 case TagDecl::TK_union: return DeclSpec::TST_union; 226 case TagDecl::TK_class: return DeclSpec::TST_class; 227 case TagDecl::TK_enum: return DeclSpec::TST_enum; 228 } 229 } 230 231 return DeclSpec::TST_unspecified; 232} 233 234bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 235 SourceLocation IILoc, 236 Scope *S, 237 const CXXScopeSpec *SS, 238 TypeTy *&SuggestedType) { 239 // We don't have anything to suggest (yet). 240 SuggestedType = 0; 241 242 // There may have been a typo in the name of the type. Look up typo 243 // results, in case we have something that we can suggest. 244 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 245 NotForRedeclaration); 246 247 // FIXME: It would be nice if we could correct for typos in built-in 248 // names, such as "itn" for "int". 249 250 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 251 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 252 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 253 !Result->isInvalidDecl()) { 254 // We found a similarly-named type or interface; suggest that. 255 if (!SS || !SS->isSet()) 256 Diag(IILoc, diag::err_unknown_typename_suggest) 257 << &II << Lookup.getLookupName() 258 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else if (DeclContext *DC = computeDeclContext(*SS, false)) 261 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 262 << &II << DC << Lookup.getLookupName() << SS->getRange() 263 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 264 Result->getNameAsString()); 265 else 266 llvm_unreachable("could not have corrected a typo here"); 267 268 Diag(Result->getLocation(), diag::note_previous_decl) 269 << Result->getDeclName(); 270 271 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 272 return true; 273 } 274 } 275 276 // FIXME: Should we move the logic that tries to recover from a missing tag 277 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 278 279 if (!SS || (!SS->isSet() && !SS->isInvalid())) 280 Diag(IILoc, diag::err_unknown_typename) << &II; 281 else if (DeclContext *DC = computeDeclContext(*SS, false)) 282 Diag(IILoc, diag::err_typename_nested_not_found) 283 << &II << DC << SS->getRange(); 284 else if (isDependentScopeSpecifier(*SS)) { 285 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 286 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 287 << SourceRange(SS->getRange().getBegin(), IILoc) 288 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 289 "typename "); 290 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 291 } else { 292 assert(SS && SS->isInvalid() && 293 "Invalid scope specifier has already been diagnosed"); 294 } 295 296 return true; 297} 298 299// Determines the context to return to after temporarily entering a 300// context. This depends in an unnecessarily complicated way on the 301// exact ordering of callbacks from the parser. 302DeclContext *Sema::getContainingDC(DeclContext *DC) { 303 304 // Functions defined inline within classes aren't parsed until we've 305 // finished parsing the top-level class, so the top-level class is 306 // the context we'll need to return to. 307 if (isa<FunctionDecl>(DC)) { 308 DC = DC->getLexicalParent(); 309 310 // A function not defined within a class will always return to its 311 // lexical context. 312 if (!isa<CXXRecordDecl>(DC)) 313 return DC; 314 315 // A C++ inline method/friend is parsed *after* the topmost class 316 // it was declared in is fully parsed ("complete"); the topmost 317 // class is the context we need to return to. 318 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 319 DC = RD; 320 321 // Return the declaration context of the topmost class the inline method is 322 // declared in. 323 return DC; 324 } 325 326 if (isa<ObjCMethodDecl>(DC)) 327 return Context.getTranslationUnitDecl(); 328 329 return DC->getLexicalParent(); 330} 331 332void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 333 assert(getContainingDC(DC) == CurContext && 334 "The next DeclContext should be lexically contained in the current one."); 335 CurContext = DC; 336 S->setEntity(DC); 337} 338 339void Sema::PopDeclContext() { 340 assert(CurContext && "DeclContext imbalance!"); 341 342 CurContext = getContainingDC(CurContext); 343} 344 345/// EnterDeclaratorContext - Used when we must lookup names in the context 346/// of a declarator's nested name specifier. 347/// 348void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 349 // C++0x [basic.lookup.unqual]p13: 350 // A name used in the definition of a static data member of class 351 // X (after the qualified-id of the static member) is looked up as 352 // if the name was used in a member function of X. 353 // C++0x [basic.lookup.unqual]p14: 354 // If a variable member of a namespace is defined outside of the 355 // scope of its namespace then any name used in the definition of 356 // the variable member (after the declarator-id) is looked up as 357 // if the definition of the variable member occurred in its 358 // namespace. 359 // Both of these imply that we should push a scope whose context 360 // is the semantic context of the declaration. We can't use 361 // PushDeclContext here because that context is not necessarily 362 // lexically contained in the current context. Fortunately, 363 // the containing scope should have the appropriate information. 364 365 assert(!S->getEntity() && "scope already has entity"); 366 367#ifndef NDEBUG 368 Scope *Ancestor = S->getParent(); 369 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 370 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 371#endif 372 373 CurContext = DC; 374 S->setEntity(DC); 375} 376 377void Sema::ExitDeclaratorContext(Scope *S) { 378 assert(S->getEntity() == CurContext && "Context imbalance!"); 379 380 // Switch back to the lexical context. The safety of this is 381 // enforced by an assert in EnterDeclaratorContext. 382 Scope *Ancestor = S->getParent(); 383 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 384 CurContext = (DeclContext*) Ancestor->getEntity(); 385 386 // We don't need to do anything with the scope, which is going to 387 // disappear. 388} 389 390/// \brief Determine whether we allow overloading of the function 391/// PrevDecl with another declaration. 392/// 393/// This routine determines whether overloading is possible, not 394/// whether some new function is actually an overload. It will return 395/// true in C++ (where we can always provide overloads) or, as an 396/// extension, in C when the previous function is already an 397/// overloaded function declaration or has the "overloadable" 398/// attribute. 399static bool AllowOverloadingOfFunction(LookupResult &Previous, 400 ASTContext &Context) { 401 if (Context.getLangOptions().CPlusPlus) 402 return true; 403 404 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 405 return true; 406 407 return (Previous.getResultKind() == LookupResult::Found 408 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 409} 410 411/// Add this decl to the scope shadowed decl chains. 412void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 413 // Move up the scope chain until we find the nearest enclosing 414 // non-transparent context. The declaration will be introduced into this 415 // scope. 416 while (S->getEntity() && 417 ((DeclContext *)S->getEntity())->isTransparentContext()) 418 S = S->getParent(); 419 420 // Add scoped declarations into their context, so that they can be 421 // found later. Declarations without a context won't be inserted 422 // into any context. 423 if (AddToContext) 424 CurContext->addDecl(D); 425 426 // Out-of-line definitions shouldn't be pushed into scope in C++. 427 // Out-of-line variable and function definitions shouldn't even in C. 428 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 429 D->isOutOfLine()) 430 return; 431 432 // Template instantiations should also not be pushed into scope. 433 if (isa<FunctionDecl>(D) && 434 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 435 return; 436 437 // If this replaces anything in the current scope, 438 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 439 IEnd = IdResolver.end(); 440 for (; I != IEnd; ++I) { 441 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 442 S->RemoveDecl(DeclPtrTy::make(*I)); 443 IdResolver.RemoveDecl(*I); 444 445 // Should only need to replace one decl. 446 break; 447 } 448 } 449 450 S->AddDecl(DeclPtrTy::make(D)); 451 IdResolver.AddDecl(D); 452} 453 454bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 455 return IdResolver.isDeclInScope(D, Ctx, Context, S); 456} 457 458static bool isOutOfScopePreviousDeclaration(NamedDecl *, 459 DeclContext*, 460 ASTContext&); 461 462/// Filters out lookup results that don't fall within the given scope 463/// as determined by isDeclInScope. 464static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 465 DeclContext *Ctx, Scope *S, 466 bool ConsiderLinkage) { 467 LookupResult::Filter F = R.makeFilter(); 468 while (F.hasNext()) { 469 NamedDecl *D = F.next(); 470 471 if (SemaRef.isDeclInScope(D, Ctx, S)) 472 continue; 473 474 if (ConsiderLinkage && 475 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 476 continue; 477 478 F.erase(); 479 } 480 481 F.done(); 482} 483 484static bool isUsingDecl(NamedDecl *D) { 485 return isa<UsingShadowDecl>(D) || 486 isa<UnresolvedUsingTypenameDecl>(D) || 487 isa<UnresolvedUsingValueDecl>(D); 488} 489 490/// Removes using shadow declarations from the lookup results. 491static void RemoveUsingDecls(LookupResult &R) { 492 LookupResult::Filter F = R.makeFilter(); 493 while (F.hasNext()) 494 if (isUsingDecl(F.next())) 495 F.erase(); 496 497 F.done(); 498} 499 500static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 501 if (D->isInvalidDecl()) 502 return false; 503 504 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 505 return false; 506 507 // White-list anything that isn't a local variable. 508 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 509 !D->getDeclContext()->isFunctionOrMethod()) 510 return false; 511 512 // Types of valid local variables should be complete, so this should succeed. 513 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 514 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 515 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 516 if (!RD->hasTrivialConstructor()) 517 return false; 518 if (!RD->hasTrivialDestructor()) 519 return false; 520 } 521 } 522 } 523 524 return true; 525} 526 527void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 528 if (S->decl_empty()) return; 529 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 530 "Scope shouldn't contain decls!"); 531 532 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 533 I != E; ++I) { 534 Decl *TmpD = (*I).getAs<Decl>(); 535 assert(TmpD && "This decl didn't get pushed??"); 536 537 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 538 NamedDecl *D = cast<NamedDecl>(TmpD); 539 540 if (!D->getDeclName()) continue; 541 542 // Diagnose unused variables in this scope. 543 if (ShouldDiagnoseUnusedDecl(D) && 544 S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 545 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 546 547 // Remove this name from our lexical scope. 548 IdResolver.RemoveDecl(D); 549 } 550} 551 552/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 553/// return 0 if one not found. 554/// 555/// \param Id the name of the Objective-C class we're looking for. If 556/// typo-correction fixes this name, the Id will be updated 557/// to the fixed name. 558/// 559/// \param RecoverLoc if provided, this routine will attempt to 560/// recover from a typo in the name of an existing Objective-C class 561/// and, if successful, will return the lookup that results from 562/// typo-correction. 563ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 564 SourceLocation RecoverLoc) { 565 // The third "scope" argument is 0 since we aren't enabling lazy built-in 566 // creation from this context. 567 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 568 569 if (!IDecl && !RecoverLoc.isInvalid()) { 570 // Perform typo correction at the given location, but only if we 571 // find an Objective-C class name. 572 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 573 if (CorrectTypo(R, TUScope, 0) && 574 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 575 Diag(RecoverLoc, diag::err_undef_interface_suggest) 576 << Id << IDecl->getDeclName() 577 << CodeModificationHint::CreateReplacement(RecoverLoc, 578 IDecl->getNameAsString()); 579 Diag(IDecl->getLocation(), diag::note_previous_decl) 580 << IDecl->getDeclName(); 581 582 Id = IDecl->getIdentifier(); 583 } 584 } 585 586 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 587} 588 589/// getNonFieldDeclScope - Retrieves the innermost scope, starting 590/// from S, where a non-field would be declared. This routine copes 591/// with the difference between C and C++ scoping rules in structs and 592/// unions. For example, the following code is well-formed in C but 593/// ill-formed in C++: 594/// @code 595/// struct S6 { 596/// enum { BAR } e; 597/// }; 598/// 599/// void test_S6() { 600/// struct S6 a; 601/// a.e = BAR; 602/// } 603/// @endcode 604/// For the declaration of BAR, this routine will return a different 605/// scope. The scope S will be the scope of the unnamed enumeration 606/// within S6. In C++, this routine will return the scope associated 607/// with S6, because the enumeration's scope is a transparent 608/// context but structures can contain non-field names. In C, this 609/// routine will return the translation unit scope, since the 610/// enumeration's scope is a transparent context and structures cannot 611/// contain non-field names. 612Scope *Sema::getNonFieldDeclScope(Scope *S) { 613 while (((S->getFlags() & Scope::DeclScope) == 0) || 614 (S->getEntity() && 615 ((DeclContext *)S->getEntity())->isTransparentContext()) || 616 (S->isClassScope() && !getLangOptions().CPlusPlus)) 617 S = S->getParent(); 618 return S; 619} 620 621void Sema::InitBuiltinVaListType() { 622 if (!Context.getBuiltinVaListType().isNull()) 623 return; 624 625 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 626 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 627 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 628 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 629} 630 631/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 632/// file scope. lazily create a decl for it. ForRedeclaration is true 633/// if we're creating this built-in in anticipation of redeclaring the 634/// built-in. 635NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 636 Scope *S, bool ForRedeclaration, 637 SourceLocation Loc) { 638 Builtin::ID BID = (Builtin::ID)bid; 639 640 if (Context.BuiltinInfo.hasVAListUse(BID)) 641 InitBuiltinVaListType(); 642 643 ASTContext::GetBuiltinTypeError Error; 644 QualType R = Context.GetBuiltinType(BID, Error); 645 switch (Error) { 646 case ASTContext::GE_None: 647 // Okay 648 break; 649 650 case ASTContext::GE_Missing_stdio: 651 if (ForRedeclaration) 652 Diag(Loc, diag::err_implicit_decl_requires_stdio) 653 << Context.BuiltinInfo.GetName(BID); 654 return 0; 655 656 case ASTContext::GE_Missing_setjmp: 657 if (ForRedeclaration) 658 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 659 << Context.BuiltinInfo.GetName(BID); 660 return 0; 661 } 662 663 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 664 Diag(Loc, diag::ext_implicit_lib_function_decl) 665 << Context.BuiltinInfo.GetName(BID) 666 << R; 667 if (Context.BuiltinInfo.getHeaderName(BID) && 668 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 669 != Diagnostic::Ignored) 670 Diag(Loc, diag::note_please_include_header) 671 << Context.BuiltinInfo.getHeaderName(BID) 672 << Context.BuiltinInfo.GetName(BID); 673 } 674 675 FunctionDecl *New = FunctionDecl::Create(Context, 676 Context.getTranslationUnitDecl(), 677 Loc, II, R, /*TInfo=*/0, 678 FunctionDecl::Extern, false, 679 /*hasPrototype=*/true); 680 New->setImplicit(); 681 682 // Create Decl objects for each parameter, adding them to the 683 // FunctionDecl. 684 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 685 llvm::SmallVector<ParmVarDecl*, 16> Params; 686 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 687 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 688 FT->getArgType(i), /*TInfo=*/0, 689 VarDecl::None, 0)); 690 New->setParams(Params.data(), Params.size()); 691 } 692 693 AddKnownFunctionAttributes(New); 694 695 // TUScope is the translation-unit scope to insert this function into. 696 // FIXME: This is hideous. We need to teach PushOnScopeChains to 697 // relate Scopes to DeclContexts, and probably eliminate CurContext 698 // entirely, but we're not there yet. 699 DeclContext *SavedContext = CurContext; 700 CurContext = Context.getTranslationUnitDecl(); 701 PushOnScopeChains(New, TUScope); 702 CurContext = SavedContext; 703 return New; 704} 705 706/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 707/// same name and scope as a previous declaration 'Old'. Figure out 708/// how to resolve this situation, merging decls or emitting 709/// diagnostics as appropriate. If there was an error, set New to be invalid. 710/// 711void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 712 // If the new decl is known invalid already, don't bother doing any 713 // merging checks. 714 if (New->isInvalidDecl()) return; 715 716 // Allow multiple definitions for ObjC built-in typedefs. 717 // FIXME: Verify the underlying types are equivalent! 718 if (getLangOptions().ObjC1) { 719 const IdentifierInfo *TypeID = New->getIdentifier(); 720 switch (TypeID->getLength()) { 721 default: break; 722 case 2: 723 if (!TypeID->isStr("id")) 724 break; 725 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 726 // Install the built-in type for 'id', ignoring the current definition. 727 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 728 return; 729 case 5: 730 if (!TypeID->isStr("Class")) 731 break; 732 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 733 // Install the built-in type for 'Class', ignoring the current definition. 734 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 735 return; 736 case 3: 737 if (!TypeID->isStr("SEL")) 738 break; 739 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 740 // Install the built-in type for 'SEL', ignoring the current definition. 741 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 742 return; 743 case 8: 744 if (!TypeID->isStr("Protocol")) 745 break; 746 Context.setObjCProtoType(New->getUnderlyingType()); 747 return; 748 } 749 // Fall through - the typedef name was not a builtin type. 750 } 751 752 // Verify the old decl was also a type. 753 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 754 if (!Old) { 755 Diag(New->getLocation(), diag::err_redefinition_different_kind) 756 << New->getDeclName(); 757 758 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 759 if (OldD->getLocation().isValid()) 760 Diag(OldD->getLocation(), diag::note_previous_definition); 761 762 return New->setInvalidDecl(); 763 } 764 765 // If the old declaration is invalid, just give up here. 766 if (Old->isInvalidDecl()) 767 return New->setInvalidDecl(); 768 769 // Determine the "old" type we'll use for checking and diagnostics. 770 QualType OldType; 771 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 772 OldType = OldTypedef->getUnderlyingType(); 773 else 774 OldType = Context.getTypeDeclType(Old); 775 776 // If the typedef types are not identical, reject them in all languages and 777 // with any extensions enabled. 778 779 if (OldType != New->getUnderlyingType() && 780 Context.getCanonicalType(OldType) != 781 Context.getCanonicalType(New->getUnderlyingType())) { 782 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 783 << New->getUnderlyingType() << OldType; 784 if (Old->getLocation().isValid()) 785 Diag(Old->getLocation(), diag::note_previous_definition); 786 return New->setInvalidDecl(); 787 } 788 789 // The types match. Link up the redeclaration chain if the old 790 // declaration was a typedef. 791 // FIXME: this is a potential source of wierdness if the type 792 // spellings don't match exactly. 793 if (isa<TypedefDecl>(Old)) 794 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 795 796 if (getLangOptions().Microsoft) 797 return; 798 799 if (getLangOptions().CPlusPlus) { 800 // C++ [dcl.typedef]p2: 801 // In a given non-class scope, a typedef specifier can be used to 802 // redefine the name of any type declared in that scope to refer 803 // to the type to which it already refers. 804 if (!isa<CXXRecordDecl>(CurContext)) 805 return; 806 807 // C++0x [dcl.typedef]p4: 808 // In a given class scope, a typedef specifier can be used to redefine 809 // any class-name declared in that scope that is not also a typedef-name 810 // to refer to the type to which it already refers. 811 // 812 // This wording came in via DR424, which was a correction to the 813 // wording in DR56, which accidentally banned code like: 814 // 815 // struct S { 816 // typedef struct A { } A; 817 // }; 818 // 819 // in the C++03 standard. We implement the C++0x semantics, which 820 // allow the above but disallow 821 // 822 // struct S { 823 // typedef int I; 824 // typedef int I; 825 // }; 826 // 827 // since that was the intent of DR56. 828 if (!isa<TypedefDecl >(Old)) 829 return; 830 831 Diag(New->getLocation(), diag::err_redefinition) 832 << New->getDeclName(); 833 Diag(Old->getLocation(), diag::note_previous_definition); 834 return New->setInvalidDecl(); 835 } 836 837 // If we have a redefinition of a typedef in C, emit a warning. This warning 838 // is normally mapped to an error, but can be controlled with 839 // -Wtypedef-redefinition. If either the original or the redefinition is 840 // in a system header, don't emit this for compatibility with GCC. 841 if (getDiagnostics().getSuppressSystemWarnings() && 842 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 843 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 844 return; 845 846 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 847 << New->getDeclName(); 848 Diag(Old->getLocation(), diag::note_previous_definition); 849 return; 850} 851 852/// DeclhasAttr - returns true if decl Declaration already has the target 853/// attribute. 854static bool 855DeclHasAttr(const Decl *decl, const Attr *target) { 856 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 857 if (attr->getKind() == target->getKind()) 858 return true; 859 860 return false; 861} 862 863/// MergeAttributes - append attributes from the Old decl to the New one. 864static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 865 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 866 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 867 Attr *NewAttr = attr->clone(C); 868 NewAttr->setInherited(true); 869 New->addAttr(NewAttr); 870 } 871 } 872} 873 874/// Used in MergeFunctionDecl to keep track of function parameters in 875/// C. 876struct GNUCompatibleParamWarning { 877 ParmVarDecl *OldParm; 878 ParmVarDecl *NewParm; 879 QualType PromotedType; 880}; 881 882 883/// getSpecialMember - get the special member enum for a method. 884static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 885 const CXXMethodDecl *MD) { 886 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 887 if (Ctor->isDefaultConstructor()) 888 return Sema::CXXDefaultConstructor; 889 if (Ctor->isCopyConstructor()) 890 return Sema::CXXCopyConstructor; 891 } 892 893 if (isa<CXXDestructorDecl>(MD)) 894 return Sema::CXXDestructor; 895 896 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 897 return Sema::CXXCopyAssignment; 898} 899 900/// canREdefineFunction - checks if a function can be redefined. Currently, 901/// only extern inline functions can be redefined, and even then only in 902/// GNU89 mode. 903static bool canRedefineFunction(const FunctionDecl *FD, 904 const LangOptions& LangOpts) { 905 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 906 FD->isInlineSpecified() && 907 FD->getStorageClass() == FunctionDecl::Extern); 908} 909 910/// MergeFunctionDecl - We just parsed a function 'New' from 911/// declarator D which has the same name and scope as a previous 912/// declaration 'Old'. Figure out how to resolve this situation, 913/// merging decls or emitting diagnostics as appropriate. 914/// 915/// In C++, New and Old must be declarations that are not 916/// overloaded. Use IsOverload to determine whether New and Old are 917/// overloaded, and to select the Old declaration that New should be 918/// merged with. 919/// 920/// Returns true if there was an error, false otherwise. 921bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 922 // Verify the old decl was also a function. 923 FunctionDecl *Old = 0; 924 if (FunctionTemplateDecl *OldFunctionTemplate 925 = dyn_cast<FunctionTemplateDecl>(OldD)) 926 Old = OldFunctionTemplate->getTemplatedDecl(); 927 else 928 Old = dyn_cast<FunctionDecl>(OldD); 929 if (!Old) { 930 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 931 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 932 Diag(Shadow->getTargetDecl()->getLocation(), 933 diag::note_using_decl_target); 934 Diag(Shadow->getUsingDecl()->getLocation(), 935 diag::note_using_decl) << 0; 936 return true; 937 } 938 939 Diag(New->getLocation(), diag::err_redefinition_different_kind) 940 << New->getDeclName(); 941 Diag(OldD->getLocation(), diag::note_previous_definition); 942 return true; 943 } 944 945 // Determine whether the previous declaration was a definition, 946 // implicit declaration, or a declaration. 947 diag::kind PrevDiag; 948 if (Old->isThisDeclarationADefinition()) 949 PrevDiag = diag::note_previous_definition; 950 else if (Old->isImplicit()) 951 PrevDiag = diag::note_previous_implicit_declaration; 952 else 953 PrevDiag = diag::note_previous_declaration; 954 955 QualType OldQType = Context.getCanonicalType(Old->getType()); 956 QualType NewQType = Context.getCanonicalType(New->getType()); 957 958 // Don't complain about this if we're in GNU89 mode and the old function 959 // is an extern inline function. 960 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 961 New->getStorageClass() == FunctionDecl::Static && 962 Old->getStorageClass() != FunctionDecl::Static && 963 !canRedefineFunction(Old, getLangOptions())) { 964 Diag(New->getLocation(), diag::err_static_non_static) 965 << New; 966 Diag(Old->getLocation(), PrevDiag); 967 return true; 968 } 969 970 // If a function is first declared with a calling convention, but is 971 // later declared or defined without one, the second decl assumes the 972 // calling convention of the first. 973 // 974 // For the new decl, we have to look at the NON-canonical type to tell the 975 // difference between a function that really doesn't have a calling 976 // convention and one that is declared cdecl. That's because in 977 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 978 // because it is the default calling convention. 979 // 980 // Note also that we DO NOT return at this point, because we still have 981 // other tests to run. 982 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 983 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 984 if (OldType->getCallConv() != CC_Default && 985 NewType->getCallConv() == CC_Default) { 986 NewQType = Context.getCallConvType(NewQType, OldType->getCallConv()); 987 New->setType(NewQType); 988 NewQType = Context.getCanonicalType(NewQType); 989 } else if (!Context.isSameCallConv(OldType->getCallConv(), 990 NewType->getCallConv())) { 991 // Calling conventions really aren't compatible, so complain. 992 Diag(New->getLocation(), diag::err_cconv_change) 993 << FunctionType::getNameForCallConv(NewType->getCallConv()) 994 << (OldType->getCallConv() == CC_Default) 995 << (OldType->getCallConv() == CC_Default ? "" : 996 FunctionType::getNameForCallConv(OldType->getCallConv())); 997 Diag(Old->getLocation(), diag::note_previous_declaration); 998 return true; 999 } 1000 1001 // FIXME: diagnose the other way around? 1002 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1003 NewQType = Context.getNoReturnType(NewQType); 1004 New->setType(NewQType); 1005 assert(NewQType.isCanonical()); 1006 } 1007 1008 if (getLangOptions().CPlusPlus) { 1009 // (C++98 13.1p2): 1010 // Certain function declarations cannot be overloaded: 1011 // -- Function declarations that differ only in the return type 1012 // cannot be overloaded. 1013 QualType OldReturnType 1014 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1015 QualType NewReturnType 1016 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1017 if (OldReturnType != NewReturnType) { 1018 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1019 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1020 return true; 1021 } 1022 1023 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1024 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1025 if (OldMethod && NewMethod) { 1026 if (!NewMethod->getFriendObjectKind() && 1027 NewMethod->getLexicalDeclContext()->isRecord()) { 1028 // -- Member function declarations with the same name and the 1029 // same parameter types cannot be overloaded if any of them 1030 // is a static member function declaration. 1031 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1032 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1033 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1034 return true; 1035 } 1036 1037 // C++ [class.mem]p1: 1038 // [...] A member shall not be declared twice in the 1039 // member-specification, except that a nested class or member 1040 // class template can be declared and then later defined. 1041 unsigned NewDiag; 1042 if (isa<CXXConstructorDecl>(OldMethod)) 1043 NewDiag = diag::err_constructor_redeclared; 1044 else if (isa<CXXDestructorDecl>(NewMethod)) 1045 NewDiag = diag::err_destructor_redeclared; 1046 else if (isa<CXXConversionDecl>(NewMethod)) 1047 NewDiag = diag::err_conv_function_redeclared; 1048 else 1049 NewDiag = diag::err_member_redeclared; 1050 1051 Diag(New->getLocation(), NewDiag); 1052 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1053 } else { 1054 if (OldMethod->isImplicit()) { 1055 Diag(NewMethod->getLocation(), 1056 diag::err_definition_of_implicitly_declared_member) 1057 << New << getSpecialMember(Context, OldMethod); 1058 1059 Diag(OldMethod->getLocation(), 1060 diag::note_previous_implicit_declaration); 1061 return true; 1062 } 1063 } 1064 } 1065 1066 // (C++98 8.3.5p3): 1067 // All declarations for a function shall agree exactly in both the 1068 // return type and the parameter-type-list. 1069 // attributes should be ignored when comparing. 1070 if (Context.getNoReturnType(OldQType, false) == 1071 Context.getNoReturnType(NewQType, false)) 1072 return MergeCompatibleFunctionDecls(New, Old); 1073 1074 // Fall through for conflicting redeclarations and redefinitions. 1075 } 1076 1077 // C: Function types need to be compatible, not identical. This handles 1078 // duplicate function decls like "void f(int); void f(enum X);" properly. 1079 if (!getLangOptions().CPlusPlus && 1080 Context.typesAreCompatible(OldQType, NewQType)) { 1081 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1082 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1083 const FunctionProtoType *OldProto = 0; 1084 if (isa<FunctionNoProtoType>(NewFuncType) && 1085 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1086 // The old declaration provided a function prototype, but the 1087 // new declaration does not. Merge in the prototype. 1088 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1089 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1090 OldProto->arg_type_end()); 1091 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1092 ParamTypes.data(), ParamTypes.size(), 1093 OldProto->isVariadic(), 1094 OldProto->getTypeQuals(), 1095 false, false, 0, 0, 1096 OldProto->getNoReturnAttr(), 1097 OldProto->getCallConv()); 1098 New->setType(NewQType); 1099 New->setHasInheritedPrototype(); 1100 1101 // Synthesize a parameter for each argument type. 1102 llvm::SmallVector<ParmVarDecl*, 16> Params; 1103 for (FunctionProtoType::arg_type_iterator 1104 ParamType = OldProto->arg_type_begin(), 1105 ParamEnd = OldProto->arg_type_end(); 1106 ParamType != ParamEnd; ++ParamType) { 1107 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1108 SourceLocation(), 0, 1109 *ParamType, /*TInfo=*/0, 1110 VarDecl::None, 0); 1111 Param->setImplicit(); 1112 Params.push_back(Param); 1113 } 1114 1115 New->setParams(Params.data(), Params.size()); 1116 } 1117 1118 return MergeCompatibleFunctionDecls(New, Old); 1119 } 1120 1121 // GNU C permits a K&R definition to follow a prototype declaration 1122 // if the declared types of the parameters in the K&R definition 1123 // match the types in the prototype declaration, even when the 1124 // promoted types of the parameters from the K&R definition differ 1125 // from the types in the prototype. GCC then keeps the types from 1126 // the prototype. 1127 // 1128 // If a variadic prototype is followed by a non-variadic K&R definition, 1129 // the K&R definition becomes variadic. This is sort of an edge case, but 1130 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1131 // C99 6.9.1p8. 1132 if (!getLangOptions().CPlusPlus && 1133 Old->hasPrototype() && !New->hasPrototype() && 1134 New->getType()->getAs<FunctionProtoType>() && 1135 Old->getNumParams() == New->getNumParams()) { 1136 llvm::SmallVector<QualType, 16> ArgTypes; 1137 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1138 const FunctionProtoType *OldProto 1139 = Old->getType()->getAs<FunctionProtoType>(); 1140 const FunctionProtoType *NewProto 1141 = New->getType()->getAs<FunctionProtoType>(); 1142 1143 // Determine whether this is the GNU C extension. 1144 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1145 NewProto->getResultType()); 1146 bool LooseCompatible = !MergedReturn.isNull(); 1147 for (unsigned Idx = 0, End = Old->getNumParams(); 1148 LooseCompatible && Idx != End; ++Idx) { 1149 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1150 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1151 if (Context.typesAreCompatible(OldParm->getType(), 1152 NewProto->getArgType(Idx))) { 1153 ArgTypes.push_back(NewParm->getType()); 1154 } else if (Context.typesAreCompatible(OldParm->getType(), 1155 NewParm->getType())) { 1156 GNUCompatibleParamWarning Warn 1157 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1158 Warnings.push_back(Warn); 1159 ArgTypes.push_back(NewParm->getType()); 1160 } else 1161 LooseCompatible = false; 1162 } 1163 1164 if (LooseCompatible) { 1165 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1166 Diag(Warnings[Warn].NewParm->getLocation(), 1167 diag::ext_param_promoted_not_compatible_with_prototype) 1168 << Warnings[Warn].PromotedType 1169 << Warnings[Warn].OldParm->getType(); 1170 Diag(Warnings[Warn].OldParm->getLocation(), 1171 diag::note_previous_declaration); 1172 } 1173 1174 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1175 ArgTypes.size(), 1176 OldProto->isVariadic(), 0, 1177 false, false, 0, 0, 1178 OldProto->getNoReturnAttr(), 1179 OldProto->getCallConv())); 1180 return MergeCompatibleFunctionDecls(New, Old); 1181 } 1182 1183 // Fall through to diagnose conflicting types. 1184 } 1185 1186 // A function that has already been declared has been redeclared or defined 1187 // with a different type- show appropriate diagnostic 1188 if (unsigned BuiltinID = Old->getBuiltinID()) { 1189 // The user has declared a builtin function with an incompatible 1190 // signature. 1191 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1192 // The function the user is redeclaring is a library-defined 1193 // function like 'malloc' or 'printf'. Warn about the 1194 // redeclaration, then pretend that we don't know about this 1195 // library built-in. 1196 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1197 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1198 << Old << Old->getType(); 1199 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1200 Old->setInvalidDecl(); 1201 return false; 1202 } 1203 1204 PrevDiag = diag::note_previous_builtin_declaration; 1205 } 1206 1207 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1208 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1209 return true; 1210} 1211 1212/// \brief Completes the merge of two function declarations that are 1213/// known to be compatible. 1214/// 1215/// This routine handles the merging of attributes and other 1216/// properties of function declarations form the old declaration to 1217/// the new declaration, once we know that New is in fact a 1218/// redeclaration of Old. 1219/// 1220/// \returns false 1221bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1222 // Merge the attributes 1223 MergeAttributes(New, Old, Context); 1224 1225 // Merge the storage class. 1226 if (Old->getStorageClass() != FunctionDecl::Extern && 1227 Old->getStorageClass() != FunctionDecl::None) 1228 New->setStorageClass(Old->getStorageClass()); 1229 1230 // Merge "pure" flag. 1231 if (Old->isPure()) 1232 New->setPure(); 1233 1234 // Merge the "deleted" flag. 1235 if (Old->isDeleted()) 1236 New->setDeleted(); 1237 1238 if (getLangOptions().CPlusPlus) 1239 return MergeCXXFunctionDecl(New, Old); 1240 1241 return false; 1242} 1243 1244/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1245/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1246/// situation, merging decls or emitting diagnostics as appropriate. 1247/// 1248/// Tentative definition rules (C99 6.9.2p2) are checked by 1249/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1250/// definitions here, since the initializer hasn't been attached. 1251/// 1252void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1253 // If the new decl is already invalid, don't do any other checking. 1254 if (New->isInvalidDecl()) 1255 return; 1256 1257 // Verify the old decl was also a variable. 1258 VarDecl *Old = 0; 1259 if (!Previous.isSingleResult() || 1260 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1261 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1262 << New->getDeclName(); 1263 Diag(Previous.getRepresentativeDecl()->getLocation(), 1264 diag::note_previous_definition); 1265 return New->setInvalidDecl(); 1266 } 1267 1268 MergeAttributes(New, Old, Context); 1269 1270 // Merge the types 1271 QualType MergedT; 1272 if (getLangOptions().CPlusPlus) { 1273 if (Context.hasSameType(New->getType(), Old->getType())) 1274 MergedT = New->getType(); 1275 // C++ [basic.link]p10: 1276 // [...] the types specified by all declarations referring to a given 1277 // object or function shall be identical, except that declarations for an 1278 // array object can specify array types that differ by the presence or 1279 // absence of a major array bound (8.3.4). 1280 else if (Old->getType()->isIncompleteArrayType() && 1281 New->getType()->isArrayType()) { 1282 CanQual<ArrayType> OldArray 1283 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1284 CanQual<ArrayType> NewArray 1285 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1286 if (OldArray->getElementType() == NewArray->getElementType()) 1287 MergedT = New->getType(); 1288 } else if (Old->getType()->isArrayType() && 1289 New->getType()->isIncompleteArrayType()) { 1290 CanQual<ArrayType> OldArray 1291 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1292 CanQual<ArrayType> NewArray 1293 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1294 if (OldArray->getElementType() == NewArray->getElementType()) 1295 MergedT = Old->getType(); 1296 } 1297 } else { 1298 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1299 } 1300 if (MergedT.isNull()) { 1301 Diag(New->getLocation(), diag::err_redefinition_different_type) 1302 << New->getDeclName(); 1303 Diag(Old->getLocation(), diag::note_previous_definition); 1304 return New->setInvalidDecl(); 1305 } 1306 New->setType(MergedT); 1307 1308 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1309 if (New->getStorageClass() == VarDecl::Static && 1310 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1311 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1312 Diag(Old->getLocation(), diag::note_previous_definition); 1313 return New->setInvalidDecl(); 1314 } 1315 // C99 6.2.2p4: 1316 // For an identifier declared with the storage-class specifier 1317 // extern in a scope in which a prior declaration of that 1318 // identifier is visible,23) if the prior declaration specifies 1319 // internal or external linkage, the linkage of the identifier at 1320 // the later declaration is the same as the linkage specified at 1321 // the prior declaration. If no prior declaration is visible, or 1322 // if the prior declaration specifies no linkage, then the 1323 // identifier has external linkage. 1324 if (New->hasExternalStorage() && Old->hasLinkage()) 1325 /* Okay */; 1326 else if (New->getStorageClass() != VarDecl::Static && 1327 Old->getStorageClass() == VarDecl::Static) { 1328 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1329 Diag(Old->getLocation(), diag::note_previous_definition); 1330 return New->setInvalidDecl(); 1331 } 1332 1333 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1334 1335 // FIXME: The test for external storage here seems wrong? We still 1336 // need to check for mismatches. 1337 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1338 // Don't complain about out-of-line definitions of static members. 1339 !(Old->getLexicalDeclContext()->isRecord() && 1340 !New->getLexicalDeclContext()->isRecord())) { 1341 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1342 Diag(Old->getLocation(), diag::note_previous_definition); 1343 return New->setInvalidDecl(); 1344 } 1345 1346 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1347 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1348 Diag(Old->getLocation(), diag::note_previous_definition); 1349 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1350 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1351 Diag(Old->getLocation(), diag::note_previous_definition); 1352 } 1353 1354 // C++ doesn't have tentative definitions, so go right ahead and check here. 1355 const VarDecl *Def; 1356 if (getLangOptions().CPlusPlus && 1357 New->isThisDeclarationADefinition() == VarDecl::Definition && 1358 (Def = Old->getDefinition())) { 1359 Diag(New->getLocation(), diag::err_redefinition) 1360 << New->getDeclName(); 1361 Diag(Def->getLocation(), diag::note_previous_definition); 1362 New->setInvalidDecl(); 1363 return; 1364 } 1365 1366 // Keep a chain of previous declarations. 1367 New->setPreviousDeclaration(Old); 1368 1369 // Inherit access appropriately. 1370 New->setAccess(Old->getAccess()); 1371} 1372 1373/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1374/// no declarator (e.g. "struct foo;") is parsed. 1375Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1376 // FIXME: Error on auto/register at file scope 1377 // FIXME: Error on inline/virtual/explicit 1378 // FIXME: Warn on useless __thread 1379 // FIXME: Warn on useless const/volatile 1380 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1381 // FIXME: Warn on useless attributes 1382 Decl *TagD = 0; 1383 TagDecl *Tag = 0; 1384 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1385 DS.getTypeSpecType() == DeclSpec::TST_struct || 1386 DS.getTypeSpecType() == DeclSpec::TST_union || 1387 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1388 TagD = static_cast<Decl *>(DS.getTypeRep()); 1389 1390 if (!TagD) // We probably had an error 1391 return DeclPtrTy(); 1392 1393 // Note that the above type specs guarantee that the 1394 // type rep is a Decl, whereas in many of the others 1395 // it's a Type. 1396 Tag = dyn_cast<TagDecl>(TagD); 1397 } 1398 1399 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1400 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1401 // or incomplete types shall not be restrict-qualified." 1402 if (TypeQuals & DeclSpec::TQ_restrict) 1403 Diag(DS.getRestrictSpecLoc(), 1404 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1405 << DS.getSourceRange(); 1406 } 1407 1408 if (DS.isFriendSpecified()) { 1409 // If we're dealing with a class template decl, assume that the 1410 // template routines are handling it. 1411 if (TagD && isa<ClassTemplateDecl>(TagD)) 1412 return DeclPtrTy(); 1413 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1414 } 1415 1416 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1417 // If there are attributes in the DeclSpec, apply them to the record. 1418 if (const AttributeList *AL = DS.getAttributes()) 1419 ProcessDeclAttributeList(S, Record, AL); 1420 1421 if (!Record->getDeclName() && Record->isDefinition() && 1422 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1423 if (getLangOptions().CPlusPlus || 1424 Record->getDeclContext()->isRecord()) 1425 return BuildAnonymousStructOrUnion(S, DS, Record); 1426 1427 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1428 << DS.getSourceRange(); 1429 } 1430 1431 // Microsoft allows unnamed struct/union fields. Don't complain 1432 // about them. 1433 // FIXME: Should we support Microsoft's extensions in this area? 1434 if (Record->getDeclName() && getLangOptions().Microsoft) 1435 return DeclPtrTy::make(Tag); 1436 } 1437 1438 if (!DS.isMissingDeclaratorOk() && 1439 DS.getTypeSpecType() != DeclSpec::TST_error) { 1440 // Warn about typedefs of enums without names, since this is an 1441 // extension in both Microsoft an GNU. 1442 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1443 Tag && isa<EnumDecl>(Tag)) { 1444 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1445 << DS.getSourceRange(); 1446 return DeclPtrTy::make(Tag); 1447 } 1448 1449 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1450 << DS.getSourceRange(); 1451 return DeclPtrTy(); 1452 } 1453 1454 return DeclPtrTy::make(Tag); 1455} 1456 1457/// We are trying to inject an anonymous member into the given scope; 1458/// check if there's an existing declaration that can't be overloaded. 1459/// 1460/// \return true if this is a forbidden redeclaration 1461static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1462 Scope *S, 1463 DeclContext *Owner, 1464 DeclarationName Name, 1465 SourceLocation NameLoc, 1466 unsigned diagnostic) { 1467 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1468 Sema::ForRedeclaration); 1469 if (!SemaRef.LookupName(R, S)) return false; 1470 1471 if (R.getAsSingle<TagDecl>()) 1472 return false; 1473 1474 // Pick a representative declaration. 1475 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1476 if (PrevDecl && Owner->isRecord()) { 1477 RecordDecl *Record = cast<RecordDecl>(Owner); 1478 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1479 return false; 1480 } 1481 1482 SemaRef.Diag(NameLoc, diagnostic) << Name; 1483 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1484 1485 return true; 1486} 1487 1488/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1489/// anonymous struct or union AnonRecord into the owning context Owner 1490/// and scope S. This routine will be invoked just after we realize 1491/// that an unnamed union or struct is actually an anonymous union or 1492/// struct, e.g., 1493/// 1494/// @code 1495/// union { 1496/// int i; 1497/// float f; 1498/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1499/// // f into the surrounding scope.x 1500/// @endcode 1501/// 1502/// This routine is recursive, injecting the names of nested anonymous 1503/// structs/unions into the owning context and scope as well. 1504bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1505 RecordDecl *AnonRecord) { 1506 unsigned diagKind 1507 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1508 : diag::err_anonymous_struct_member_redecl; 1509 1510 bool Invalid = false; 1511 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1512 FEnd = AnonRecord->field_end(); 1513 F != FEnd; ++F) { 1514 if ((*F)->getDeclName()) { 1515 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1516 (*F)->getLocation(), diagKind)) { 1517 // C++ [class.union]p2: 1518 // The names of the members of an anonymous union shall be 1519 // distinct from the names of any other entity in the 1520 // scope in which the anonymous union is declared. 1521 Invalid = true; 1522 } else { 1523 // C++ [class.union]p2: 1524 // For the purpose of name lookup, after the anonymous union 1525 // definition, the members of the anonymous union are 1526 // considered to have been defined in the scope in which the 1527 // anonymous union is declared. 1528 Owner->makeDeclVisibleInContext(*F); 1529 S->AddDecl(DeclPtrTy::make(*F)); 1530 IdResolver.AddDecl(*F); 1531 } 1532 } else if (const RecordType *InnerRecordType 1533 = (*F)->getType()->getAs<RecordType>()) { 1534 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1535 if (InnerRecord->isAnonymousStructOrUnion()) 1536 Invalid = Invalid || 1537 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1538 } 1539 } 1540 1541 return Invalid; 1542} 1543 1544/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1545/// anonymous structure or union. Anonymous unions are a C++ feature 1546/// (C++ [class.union]) and a GNU C extension; anonymous structures 1547/// are a GNU C and GNU C++ extension. 1548Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1549 RecordDecl *Record) { 1550 DeclContext *Owner = Record->getDeclContext(); 1551 1552 // Diagnose whether this anonymous struct/union is an extension. 1553 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1554 Diag(Record->getLocation(), diag::ext_anonymous_union); 1555 else if (!Record->isUnion()) 1556 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1557 1558 // C and C++ require different kinds of checks for anonymous 1559 // structs/unions. 1560 bool Invalid = false; 1561 if (getLangOptions().CPlusPlus) { 1562 const char* PrevSpec = 0; 1563 unsigned DiagID; 1564 // C++ [class.union]p3: 1565 // Anonymous unions declared in a named namespace or in the 1566 // global namespace shall be declared static. 1567 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1568 (isa<TranslationUnitDecl>(Owner) || 1569 (isa<NamespaceDecl>(Owner) && 1570 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1571 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1572 Invalid = true; 1573 1574 // Recover by adding 'static'. 1575 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1576 PrevSpec, DiagID); 1577 } 1578 // C++ [class.union]p3: 1579 // A storage class is not allowed in a declaration of an 1580 // anonymous union in a class scope. 1581 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1582 isa<RecordDecl>(Owner)) { 1583 Diag(DS.getStorageClassSpecLoc(), 1584 diag::err_anonymous_union_with_storage_spec); 1585 Invalid = true; 1586 1587 // Recover by removing the storage specifier. 1588 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1589 PrevSpec, DiagID); 1590 } 1591 1592 // C++ [class.union]p2: 1593 // The member-specification of an anonymous union shall only 1594 // define non-static data members. [Note: nested types and 1595 // functions cannot be declared within an anonymous union. ] 1596 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1597 MemEnd = Record->decls_end(); 1598 Mem != MemEnd; ++Mem) { 1599 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1600 // C++ [class.union]p3: 1601 // An anonymous union shall not have private or protected 1602 // members (clause 11). 1603 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1604 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1605 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1606 Invalid = true; 1607 } 1608 } else if ((*Mem)->isImplicit()) { 1609 // Any implicit members are fine. 1610 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1611 // This is a type that showed up in an 1612 // elaborated-type-specifier inside the anonymous struct or 1613 // union, but which actually declares a type outside of the 1614 // anonymous struct or union. It's okay. 1615 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1616 if (!MemRecord->isAnonymousStructOrUnion() && 1617 MemRecord->getDeclName()) { 1618 // This is a nested type declaration. 1619 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1620 << (int)Record->isUnion(); 1621 Invalid = true; 1622 } 1623 } else { 1624 // We have something that isn't a non-static data 1625 // member. Complain about it. 1626 unsigned DK = diag::err_anonymous_record_bad_member; 1627 if (isa<TypeDecl>(*Mem)) 1628 DK = diag::err_anonymous_record_with_type; 1629 else if (isa<FunctionDecl>(*Mem)) 1630 DK = diag::err_anonymous_record_with_function; 1631 else if (isa<VarDecl>(*Mem)) 1632 DK = diag::err_anonymous_record_with_static; 1633 Diag((*Mem)->getLocation(), DK) 1634 << (int)Record->isUnion(); 1635 Invalid = true; 1636 } 1637 } 1638 } 1639 1640 if (!Record->isUnion() && !Owner->isRecord()) { 1641 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1642 << (int)getLangOptions().CPlusPlus; 1643 Invalid = true; 1644 } 1645 1646 // Mock up a declarator. 1647 Declarator Dc(DS, Declarator::TypeNameContext); 1648 TypeSourceInfo *TInfo = 0; 1649 GetTypeForDeclarator(Dc, S, &TInfo); 1650 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1651 1652 // Create a declaration for this anonymous struct/union. 1653 NamedDecl *Anon = 0; 1654 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1655 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1656 /*IdentifierInfo=*/0, 1657 Context.getTypeDeclType(Record), 1658 TInfo, 1659 /*BitWidth=*/0, /*Mutable=*/false); 1660 Anon->setAccess(AS_public); 1661 if (getLangOptions().CPlusPlus) 1662 FieldCollector->Add(cast<FieldDecl>(Anon)); 1663 } else { 1664 VarDecl::StorageClass SC; 1665 switch (DS.getStorageClassSpec()) { 1666 default: assert(0 && "Unknown storage class!"); 1667 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1668 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1669 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1670 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1671 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1672 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1673 case DeclSpec::SCS_mutable: 1674 // mutable can only appear on non-static class members, so it's always 1675 // an error here 1676 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1677 Invalid = true; 1678 SC = VarDecl::None; 1679 break; 1680 } 1681 1682 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1683 /*IdentifierInfo=*/0, 1684 Context.getTypeDeclType(Record), 1685 TInfo, 1686 SC); 1687 } 1688 Anon->setImplicit(); 1689 1690 // Add the anonymous struct/union object to the current 1691 // context. We'll be referencing this object when we refer to one of 1692 // its members. 1693 Owner->addDecl(Anon); 1694 1695 // Inject the members of the anonymous struct/union into the owning 1696 // context and into the identifier resolver chain for name lookup 1697 // purposes. 1698 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1699 Invalid = true; 1700 1701 // Mark this as an anonymous struct/union type. Note that we do not 1702 // do this until after we have already checked and injected the 1703 // members of this anonymous struct/union type, because otherwise 1704 // the members could be injected twice: once by DeclContext when it 1705 // builds its lookup table, and once by 1706 // InjectAnonymousStructOrUnionMembers. 1707 Record->setAnonymousStructOrUnion(true); 1708 1709 if (Invalid) 1710 Anon->setInvalidDecl(); 1711 1712 return DeclPtrTy::make(Anon); 1713} 1714 1715 1716/// GetNameForDeclarator - Determine the full declaration name for the 1717/// given Declarator. 1718DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1719 return GetNameFromUnqualifiedId(D.getName()); 1720} 1721 1722/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1723DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1724 switch (Name.getKind()) { 1725 case UnqualifiedId::IK_Identifier: 1726 return DeclarationName(Name.Identifier); 1727 1728 case UnqualifiedId::IK_OperatorFunctionId: 1729 return Context.DeclarationNames.getCXXOperatorName( 1730 Name.OperatorFunctionId.Operator); 1731 1732 case UnqualifiedId::IK_LiteralOperatorId: 1733 return Context.DeclarationNames.getCXXLiteralOperatorName( 1734 Name.Identifier); 1735 1736 case UnqualifiedId::IK_ConversionFunctionId: { 1737 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1738 if (Ty.isNull()) 1739 return DeclarationName(); 1740 1741 return Context.DeclarationNames.getCXXConversionFunctionName( 1742 Context.getCanonicalType(Ty)); 1743 } 1744 1745 case UnqualifiedId::IK_ConstructorName: { 1746 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1747 if (Ty.isNull()) 1748 return DeclarationName(); 1749 1750 return Context.DeclarationNames.getCXXConstructorName( 1751 Context.getCanonicalType(Ty)); 1752 } 1753 1754 case UnqualifiedId::IK_ConstructorTemplateId: { 1755 // In well-formed code, we can only have a constructor 1756 // template-id that refers to the current context, so go there 1757 // to find the actual type being constructed. 1758 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1759 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1760 return DeclarationName(); 1761 1762 // Determine the type of the class being constructed. 1763 QualType CurClassType = Context.getTypeDeclType(CurClass); 1764 1765 // FIXME: Check two things: that the template-id names the same type as 1766 // CurClassType, and that the template-id does not occur when the name 1767 // was qualified. 1768 1769 return Context.DeclarationNames.getCXXConstructorName( 1770 Context.getCanonicalType(CurClassType)); 1771 } 1772 1773 case UnqualifiedId::IK_DestructorName: { 1774 QualType Ty = GetTypeFromParser(Name.DestructorName); 1775 if (Ty.isNull()) 1776 return DeclarationName(); 1777 1778 return Context.DeclarationNames.getCXXDestructorName( 1779 Context.getCanonicalType(Ty)); 1780 } 1781 1782 case UnqualifiedId::IK_TemplateId: { 1783 TemplateName TName 1784 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1785 return Context.getNameForTemplate(TName); 1786 } 1787 } 1788 1789 assert(false && "Unknown name kind"); 1790 return DeclarationName(); 1791} 1792 1793/// isNearlyMatchingFunction - Determine whether the C++ functions 1794/// Declaration and Definition are "nearly" matching. This heuristic 1795/// is used to improve diagnostics in the case where an out-of-line 1796/// function definition doesn't match any declaration within 1797/// the class or namespace. 1798static bool isNearlyMatchingFunction(ASTContext &Context, 1799 FunctionDecl *Declaration, 1800 FunctionDecl *Definition) { 1801 if (Declaration->param_size() != Definition->param_size()) 1802 return false; 1803 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1804 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1805 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1806 1807 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1808 DefParamTy.getNonReferenceType())) 1809 return false; 1810 } 1811 1812 return true; 1813} 1814 1815Sema::DeclPtrTy 1816Sema::HandleDeclarator(Scope *S, Declarator &D, 1817 MultiTemplateParamsArg TemplateParamLists, 1818 bool IsFunctionDefinition) { 1819 DeclarationName Name = GetNameForDeclarator(D); 1820 1821 // All of these full declarators require an identifier. If it doesn't have 1822 // one, the ParsedFreeStandingDeclSpec action should be used. 1823 if (!Name) { 1824 if (!D.isInvalidType()) // Reject this if we think it is valid. 1825 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1826 diag::err_declarator_need_ident) 1827 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1828 return DeclPtrTy(); 1829 } 1830 1831 // The scope passed in may not be a decl scope. Zip up the scope tree until 1832 // we find one that is. 1833 while ((S->getFlags() & Scope::DeclScope) == 0 || 1834 (S->getFlags() & Scope::TemplateParamScope) != 0) 1835 S = S->getParent(); 1836 1837 // If this is an out-of-line definition of a member of a class template 1838 // or class template partial specialization, we may need to rebuild the 1839 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1840 // for more information. 1841 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1842 // handle expressions properly. 1843 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1844 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1845 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1846 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1847 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1848 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1849 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1850 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1851 // FIXME: Preserve type source info. 1852 QualType T = GetTypeFromParser(DS.getTypeRep()); 1853 1854 DeclContext *SavedContext = CurContext; 1855 CurContext = DC; 1856 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1857 CurContext = SavedContext; 1858 1859 if (T.isNull()) 1860 return DeclPtrTy(); 1861 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1862 } 1863 } 1864 1865 DeclContext *DC; 1866 NamedDecl *New; 1867 1868 TypeSourceInfo *TInfo = 0; 1869 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1870 1871 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1872 ForRedeclaration); 1873 1874 // See if this is a redefinition of a variable in the same scope. 1875 if (D.getCXXScopeSpec().isInvalid()) { 1876 DC = CurContext; 1877 D.setInvalidType(); 1878 } else if (!D.getCXXScopeSpec().isSet()) { 1879 bool IsLinkageLookup = false; 1880 1881 // If the declaration we're planning to build will be a function 1882 // or object with linkage, then look for another declaration with 1883 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1884 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1885 /* Do nothing*/; 1886 else if (R->isFunctionType()) { 1887 if (CurContext->isFunctionOrMethod() || 1888 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1889 IsLinkageLookup = true; 1890 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1891 IsLinkageLookup = true; 1892 else if (CurContext->getLookupContext()->isTranslationUnit() && 1893 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1894 IsLinkageLookup = true; 1895 1896 if (IsLinkageLookup) 1897 Previous.clear(LookupRedeclarationWithLinkage); 1898 1899 DC = CurContext; 1900 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1901 } else { // Something like "int foo::x;" 1902 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1903 1904 if (!DC) { 1905 // If we could not compute the declaration context, it's because the 1906 // declaration context is dependent but does not refer to a class, 1907 // class template, or class template partial specialization. Complain 1908 // and return early, to avoid the coming semantic disaster. 1909 Diag(D.getIdentifierLoc(), 1910 diag::err_template_qualified_declarator_no_match) 1911 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1912 << D.getCXXScopeSpec().getRange(); 1913 return DeclPtrTy(); 1914 } 1915 1916 if (!DC->isDependentContext() && 1917 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1918 return DeclPtrTy(); 1919 1920 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 1921 Diag(D.getIdentifierLoc(), 1922 diag::err_member_def_undefined_record) 1923 << Name << DC << D.getCXXScopeSpec().getRange(); 1924 D.setInvalidType(); 1925 } 1926 1927 LookupQualifiedName(Previous, DC); 1928 1929 // Don't consider using declarations as previous declarations for 1930 // out-of-line members. 1931 RemoveUsingDecls(Previous); 1932 1933 // C++ 7.3.1.2p2: 1934 // Members (including explicit specializations of templates) of a named 1935 // namespace can also be defined outside that namespace by explicit 1936 // qualification of the name being defined, provided that the entity being 1937 // defined was already declared in the namespace and the definition appears 1938 // after the point of declaration in a namespace that encloses the 1939 // declarations namespace. 1940 // 1941 // Note that we only check the context at this point. We don't yet 1942 // have enough information to make sure that PrevDecl is actually 1943 // the declaration we want to match. For example, given: 1944 // 1945 // class X { 1946 // void f(); 1947 // void f(float); 1948 // }; 1949 // 1950 // void X::f(int) { } // ill-formed 1951 // 1952 // In this case, PrevDecl will point to the overload set 1953 // containing the two f's declared in X, but neither of them 1954 // matches. 1955 1956 // First check whether we named the global scope. 1957 if (isa<TranslationUnitDecl>(DC)) { 1958 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1959 << Name << D.getCXXScopeSpec().getRange(); 1960 } else { 1961 DeclContext *Cur = CurContext; 1962 while (isa<LinkageSpecDecl>(Cur)) 1963 Cur = Cur->getParent(); 1964 if (!Cur->Encloses(DC)) { 1965 // The qualifying scope doesn't enclose the original declaration. 1966 // Emit diagnostic based on current scope. 1967 SourceLocation L = D.getIdentifierLoc(); 1968 SourceRange R = D.getCXXScopeSpec().getRange(); 1969 if (isa<FunctionDecl>(Cur)) 1970 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1971 else 1972 Diag(L, diag::err_invalid_declarator_scope) 1973 << Name << cast<NamedDecl>(DC) << R; 1974 D.setInvalidType(); 1975 } 1976 } 1977 } 1978 1979 if (Previous.isSingleResult() && 1980 Previous.getFoundDecl()->isTemplateParameter()) { 1981 // Maybe we will complain about the shadowed template parameter. 1982 if (!D.isInvalidType()) 1983 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 1984 Previous.getFoundDecl())) 1985 D.setInvalidType(); 1986 1987 // Just pretend that we didn't see the previous declaration. 1988 Previous.clear(); 1989 } 1990 1991 // In C++, the previous declaration we find might be a tag type 1992 // (class or enum). In this case, the new declaration will hide the 1993 // tag type. Note that this does does not apply if we're declaring a 1994 // typedef (C++ [dcl.typedef]p4). 1995 if (Previous.isSingleTagDecl() && 1996 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1997 Previous.clear(); 1998 1999 bool Redeclaration = false; 2000 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2001 if (TemplateParamLists.size()) { 2002 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2003 return DeclPtrTy(); 2004 } 2005 2006 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2007 } else if (R->isFunctionType()) { 2008 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2009 move(TemplateParamLists), 2010 IsFunctionDefinition, Redeclaration); 2011 } else { 2012 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2013 move(TemplateParamLists), 2014 Redeclaration); 2015 } 2016 2017 if (New == 0) 2018 return DeclPtrTy(); 2019 2020 // If this has an identifier and is not an invalid redeclaration or 2021 // function template specialization, add it to the scope stack. 2022 if (Name && !(Redeclaration && New->isInvalidDecl())) 2023 PushOnScopeChains(New, S); 2024 2025 return DeclPtrTy::make(New); 2026} 2027 2028/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2029/// types into constant array types in certain situations which would otherwise 2030/// be errors (for GCC compatibility). 2031static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2032 ASTContext &Context, 2033 bool &SizeIsNegative) { 2034 // This method tries to turn a variable array into a constant 2035 // array even when the size isn't an ICE. This is necessary 2036 // for compatibility with code that depends on gcc's buggy 2037 // constant expression folding, like struct {char x[(int)(char*)2];} 2038 SizeIsNegative = false; 2039 2040 QualifierCollector Qs; 2041 const Type *Ty = Qs.strip(T); 2042 2043 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2044 QualType Pointee = PTy->getPointeeType(); 2045 QualType FixedType = 2046 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2047 if (FixedType.isNull()) return FixedType; 2048 FixedType = Context.getPointerType(FixedType); 2049 return Qs.apply(FixedType); 2050 } 2051 2052 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2053 if (!VLATy) 2054 return QualType(); 2055 // FIXME: We should probably handle this case 2056 if (VLATy->getElementType()->isVariablyModifiedType()) 2057 return QualType(); 2058 2059 Expr::EvalResult EvalResult; 2060 if (!VLATy->getSizeExpr() || 2061 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2062 !EvalResult.Val.isInt()) 2063 return QualType(); 2064 2065 llvm::APSInt &Res = EvalResult.Val.getInt(); 2066 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2067 // TODO: preserve the size expression in declarator info 2068 return Context.getConstantArrayType(VLATy->getElementType(), 2069 Res, ArrayType::Normal, 0); 2070 } 2071 2072 SizeIsNegative = true; 2073 return QualType(); 2074} 2075 2076/// \brief Register the given locally-scoped external C declaration so 2077/// that it can be found later for redeclarations 2078void 2079Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2080 const LookupResult &Previous, 2081 Scope *S) { 2082 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2083 "Decl is not a locally-scoped decl!"); 2084 // Note that we have a locally-scoped external with this name. 2085 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2086 2087 if (!Previous.isSingleResult()) 2088 return; 2089 2090 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2091 2092 // If there was a previous declaration of this variable, it may be 2093 // in our identifier chain. Update the identifier chain with the new 2094 // declaration. 2095 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2096 // The previous declaration was found on the identifer resolver 2097 // chain, so remove it from its scope. 2098 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2099 S = S->getParent(); 2100 2101 if (S) 2102 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2103 } 2104} 2105 2106/// \brief Diagnose function specifiers on a declaration of an identifier that 2107/// does not identify a function. 2108void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2109 // FIXME: We should probably indicate the identifier in question to avoid 2110 // confusion for constructs like "inline int a(), b;" 2111 if (D.getDeclSpec().isInlineSpecified()) 2112 Diag(D.getDeclSpec().getInlineSpecLoc(), 2113 diag::err_inline_non_function); 2114 2115 if (D.getDeclSpec().isVirtualSpecified()) 2116 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2117 diag::err_virtual_non_function); 2118 2119 if (D.getDeclSpec().isExplicitSpecified()) 2120 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2121 diag::err_explicit_non_function); 2122} 2123 2124NamedDecl* 2125Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2126 QualType R, TypeSourceInfo *TInfo, 2127 LookupResult &Previous, bool &Redeclaration) { 2128 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2129 if (D.getCXXScopeSpec().isSet()) { 2130 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2131 << D.getCXXScopeSpec().getRange(); 2132 D.setInvalidType(); 2133 // Pretend we didn't see the scope specifier. 2134 DC = CurContext; 2135 Previous.clear(); 2136 } 2137 2138 if (getLangOptions().CPlusPlus) { 2139 // Check that there are no default arguments (C++ only). 2140 CheckExtraCXXDefaultArguments(D); 2141 } 2142 2143 DiagnoseFunctionSpecifiers(D); 2144 2145 if (D.getDeclSpec().isThreadSpecified()) 2146 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2147 2148 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2149 if (!NewTD) return 0; 2150 2151 // Handle attributes prior to checking for duplicates in MergeVarDecl 2152 ProcessDeclAttributes(S, NewTD, D); 2153 2154 // Merge the decl with the existing one if appropriate. If the decl is 2155 // in an outer scope, it isn't the same thing. 2156 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2157 if (!Previous.empty()) { 2158 Redeclaration = true; 2159 MergeTypeDefDecl(NewTD, Previous); 2160 } 2161 2162 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2163 // then it shall have block scope. 2164 QualType T = NewTD->getUnderlyingType(); 2165 if (T->isVariablyModifiedType()) { 2166 FunctionNeedsScopeChecking() = true; 2167 2168 if (S->getFnParent() == 0) { 2169 bool SizeIsNegative; 2170 QualType FixedTy = 2171 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2172 if (!FixedTy.isNull()) { 2173 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2174 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2175 } else { 2176 if (SizeIsNegative) 2177 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2178 else if (T->isVariableArrayType()) 2179 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2180 else 2181 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2182 NewTD->setInvalidDecl(); 2183 } 2184 } 2185 } 2186 2187 // If this is the C FILE type, notify the AST context. 2188 if (IdentifierInfo *II = NewTD->getIdentifier()) 2189 if (!NewTD->isInvalidDecl() && 2190 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2191 if (II->isStr("FILE")) 2192 Context.setFILEDecl(NewTD); 2193 else if (II->isStr("jmp_buf")) 2194 Context.setjmp_bufDecl(NewTD); 2195 else if (II->isStr("sigjmp_buf")) 2196 Context.setsigjmp_bufDecl(NewTD); 2197 } 2198 2199 return NewTD; 2200} 2201 2202/// \brief Determines whether the given declaration is an out-of-scope 2203/// previous declaration. 2204/// 2205/// This routine should be invoked when name lookup has found a 2206/// previous declaration (PrevDecl) that is not in the scope where a 2207/// new declaration by the same name is being introduced. If the new 2208/// declaration occurs in a local scope, previous declarations with 2209/// linkage may still be considered previous declarations (C99 2210/// 6.2.2p4-5, C++ [basic.link]p6). 2211/// 2212/// \param PrevDecl the previous declaration found by name 2213/// lookup 2214/// 2215/// \param DC the context in which the new declaration is being 2216/// declared. 2217/// 2218/// \returns true if PrevDecl is an out-of-scope previous declaration 2219/// for a new delcaration with the same name. 2220static bool 2221isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2222 ASTContext &Context) { 2223 if (!PrevDecl) 2224 return 0; 2225 2226 if (!PrevDecl->hasLinkage()) 2227 return false; 2228 2229 if (Context.getLangOptions().CPlusPlus) { 2230 // C++ [basic.link]p6: 2231 // If there is a visible declaration of an entity with linkage 2232 // having the same name and type, ignoring entities declared 2233 // outside the innermost enclosing namespace scope, the block 2234 // scope declaration declares that same entity and receives the 2235 // linkage of the previous declaration. 2236 DeclContext *OuterContext = DC->getLookupContext(); 2237 if (!OuterContext->isFunctionOrMethod()) 2238 // This rule only applies to block-scope declarations. 2239 return false; 2240 else { 2241 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2242 if (PrevOuterContext->isRecord()) 2243 // We found a member function: ignore it. 2244 return false; 2245 else { 2246 // Find the innermost enclosing namespace for the new and 2247 // previous declarations. 2248 while (!OuterContext->isFileContext()) 2249 OuterContext = OuterContext->getParent(); 2250 while (!PrevOuterContext->isFileContext()) 2251 PrevOuterContext = PrevOuterContext->getParent(); 2252 2253 // The previous declaration is in a different namespace, so it 2254 // isn't the same function. 2255 if (OuterContext->getPrimaryContext() != 2256 PrevOuterContext->getPrimaryContext()) 2257 return false; 2258 } 2259 } 2260 } 2261 2262 return true; 2263} 2264 2265static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2266 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2267 if (!SS.isSet()) return; 2268 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2269 SS.getRange()); 2270} 2271 2272NamedDecl* 2273Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2274 QualType R, TypeSourceInfo *TInfo, 2275 LookupResult &Previous, 2276 MultiTemplateParamsArg TemplateParamLists, 2277 bool &Redeclaration) { 2278 DeclarationName Name = GetNameForDeclarator(D); 2279 2280 // Check that there are no default arguments (C++ only). 2281 if (getLangOptions().CPlusPlus) 2282 CheckExtraCXXDefaultArguments(D); 2283 2284 VarDecl *NewVD; 2285 VarDecl::StorageClass SC; 2286 switch (D.getDeclSpec().getStorageClassSpec()) { 2287 default: assert(0 && "Unknown storage class!"); 2288 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2289 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2290 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2291 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2292 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2293 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2294 case DeclSpec::SCS_mutable: 2295 // mutable can only appear on non-static class members, so it's always 2296 // an error here 2297 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2298 D.setInvalidType(); 2299 SC = VarDecl::None; 2300 break; 2301 } 2302 2303 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2304 if (!II) { 2305 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2306 << Name.getAsString(); 2307 return 0; 2308 } 2309 2310 DiagnoseFunctionSpecifiers(D); 2311 2312 if (!DC->isRecord() && S->getFnParent() == 0) { 2313 // C99 6.9p2: The storage-class specifiers auto and register shall not 2314 // appear in the declaration specifiers in an external declaration. 2315 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2316 2317 // If this is a register variable with an asm label specified, then this 2318 // is a GNU extension. 2319 if (SC == VarDecl::Register && D.getAsmLabel()) 2320 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2321 else 2322 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2323 D.setInvalidType(); 2324 } 2325 } 2326 if (DC->isRecord() && !CurContext->isRecord()) { 2327 // This is an out-of-line definition of a static data member. 2328 if (SC == VarDecl::Static) { 2329 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2330 diag::err_static_out_of_line) 2331 << CodeModificationHint::CreateRemoval( 2332 D.getDeclSpec().getStorageClassSpecLoc()); 2333 } else if (SC == VarDecl::None) 2334 SC = VarDecl::Static; 2335 } 2336 if (SC == VarDecl::Static) { 2337 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2338 if (RD->isLocalClass()) 2339 Diag(D.getIdentifierLoc(), 2340 diag::err_static_data_member_not_allowed_in_local_class) 2341 << Name << RD->getDeclName(); 2342 } 2343 } 2344 2345 // Match up the template parameter lists with the scope specifier, then 2346 // determine whether we have a template or a template specialization. 2347 bool isExplicitSpecialization = false; 2348 if (TemplateParameterList *TemplateParams 2349 = MatchTemplateParametersToScopeSpecifier( 2350 D.getDeclSpec().getSourceRange().getBegin(), 2351 D.getCXXScopeSpec(), 2352 (TemplateParameterList**)TemplateParamLists.get(), 2353 TemplateParamLists.size(), 2354 isExplicitSpecialization)) { 2355 if (TemplateParams->size() > 0) { 2356 // There is no such thing as a variable template. 2357 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2358 << II 2359 << SourceRange(TemplateParams->getTemplateLoc(), 2360 TemplateParams->getRAngleLoc()); 2361 return 0; 2362 } else { 2363 // There is an extraneous 'template<>' for this variable. Complain 2364 // about it, but allow the declaration of the variable. 2365 Diag(TemplateParams->getTemplateLoc(), 2366 diag::err_template_variable_noparams) 2367 << II 2368 << SourceRange(TemplateParams->getTemplateLoc(), 2369 TemplateParams->getRAngleLoc()); 2370 2371 isExplicitSpecialization = true; 2372 } 2373 } 2374 2375 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2376 II, R, TInfo, SC); 2377 2378 if (D.isInvalidType()) 2379 NewVD->setInvalidDecl(); 2380 2381 SetNestedNameSpecifier(NewVD, D); 2382 2383 if (D.getDeclSpec().isThreadSpecified()) { 2384 if (NewVD->hasLocalStorage()) 2385 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2386 else if (!Context.Target.isTLSSupported()) 2387 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2388 else 2389 NewVD->setThreadSpecified(true); 2390 } 2391 2392 // Set the lexical context. If the declarator has a C++ scope specifier, the 2393 // lexical context will be different from the semantic context. 2394 NewVD->setLexicalDeclContext(CurContext); 2395 2396 // Handle attributes prior to checking for duplicates in MergeVarDecl 2397 ProcessDeclAttributes(S, NewVD, D); 2398 2399 // Handle GNU asm-label extension (encoded as an attribute). 2400 if (Expr *E = (Expr*) D.getAsmLabel()) { 2401 // The parser guarantees this is a string. 2402 StringLiteral *SE = cast<StringLiteral>(E); 2403 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2404 } 2405 2406 // Diagnose shadowed variables before filtering for scope. 2407 if (!D.getCXXScopeSpec().isSet()) 2408 CheckShadow(S, NewVD, Previous); 2409 2410 // Don't consider existing declarations that are in a different 2411 // scope and are out-of-semantic-context declarations (if the new 2412 // declaration has linkage). 2413 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2414 2415 // Merge the decl with the existing one if appropriate. 2416 if (!Previous.empty()) { 2417 if (Previous.isSingleResult() && 2418 isa<FieldDecl>(Previous.getFoundDecl()) && 2419 D.getCXXScopeSpec().isSet()) { 2420 // The user tried to define a non-static data member 2421 // out-of-line (C++ [dcl.meaning]p1). 2422 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2423 << D.getCXXScopeSpec().getRange(); 2424 Previous.clear(); 2425 NewVD->setInvalidDecl(); 2426 } 2427 } else if (D.getCXXScopeSpec().isSet()) { 2428 // No previous declaration in the qualifying scope. 2429 Diag(D.getIdentifierLoc(), diag::err_no_member) 2430 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2431 << D.getCXXScopeSpec().getRange(); 2432 NewVD->setInvalidDecl(); 2433 } 2434 2435 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2436 2437 // This is an explicit specialization of a static data member. Check it. 2438 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2439 CheckMemberSpecialization(NewVD, Previous)) 2440 NewVD->setInvalidDecl(); 2441 2442 // attributes declared post-definition are currently ignored 2443 if (Previous.isSingleResult()) { 2444 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2445 if (Def && (Def = Def->getDefinition()) && 2446 Def != NewVD && D.hasAttributes()) { 2447 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2448 Diag(Def->getLocation(), diag::note_previous_definition); 2449 } 2450 } 2451 2452 // If this is a locally-scoped extern C variable, update the map of 2453 // such variables. 2454 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2455 !NewVD->isInvalidDecl()) 2456 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2457 2458 return NewVD; 2459} 2460 2461/// \brief Diagnose variable or built-in function shadowing. Implements 2462/// -Wshadow. 2463/// 2464/// This method is called whenever a VarDecl is added to a "useful" 2465/// scope. 2466/// 2467/// \param S the scope in which the shadowing name is being declared 2468/// \param R the lookup of the name 2469/// 2470void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2471 // Return if warning is ignored. 2472 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2473 return; 2474 2475 // Don't diagnose declarations at file scope. The scope might not 2476 // have a DeclContext if (e.g.) we're parsing a function prototype. 2477 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2478 if (NewDC && NewDC->isFileContext()) 2479 return; 2480 2481 // Only diagnose if we're shadowing an unambiguous field or variable. 2482 if (R.getResultKind() != LookupResult::Found) 2483 return; 2484 2485 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2486 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2487 return; 2488 2489 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2490 2491 // Only warn about certain kinds of shadowing for class members. 2492 if (NewDC && NewDC->isRecord()) { 2493 // In particular, don't warn about shadowing non-class members. 2494 if (!OldDC->isRecord()) 2495 return; 2496 2497 // TODO: should we warn about static data members shadowing 2498 // static data members from base classes? 2499 2500 // TODO: don't diagnose for inaccessible shadowed members. 2501 // This is hard to do perfectly because we might friend the 2502 // shadowing context, but that's just a false negative. 2503 } 2504 2505 // Determine what kind of declaration we're shadowing. 2506 unsigned Kind; 2507 if (isa<RecordDecl>(OldDC)) { 2508 if (isa<FieldDecl>(ShadowedDecl)) 2509 Kind = 3; // field 2510 else 2511 Kind = 2; // static data member 2512 } else if (OldDC->isFileContext()) 2513 Kind = 1; // global 2514 else 2515 Kind = 0; // local 2516 2517 DeclarationName Name = R.getLookupName(); 2518 2519 // Emit warning and note. 2520 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2521 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2522} 2523 2524/// \brief Check -Wshadow without the advantage of a previous lookup. 2525void Sema::CheckShadow(Scope *S, VarDecl *D) { 2526 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2527 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2528 LookupName(R, S); 2529 CheckShadow(S, D, R); 2530} 2531 2532/// \brief Perform semantic checking on a newly-created variable 2533/// declaration. 2534/// 2535/// This routine performs all of the type-checking required for a 2536/// variable declaration once it has been built. It is used both to 2537/// check variables after they have been parsed and their declarators 2538/// have been translated into a declaration, and to check variables 2539/// that have been instantiated from a template. 2540/// 2541/// Sets NewVD->isInvalidDecl() if an error was encountered. 2542void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2543 LookupResult &Previous, 2544 bool &Redeclaration) { 2545 // If the decl is already known invalid, don't check it. 2546 if (NewVD->isInvalidDecl()) 2547 return; 2548 2549 QualType T = NewVD->getType(); 2550 2551 if (T->isObjCInterfaceType()) { 2552 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2553 return NewVD->setInvalidDecl(); 2554 } 2555 2556 // Emit an error if an address space was applied to decl with local storage. 2557 // This includes arrays of objects with address space qualifiers, but not 2558 // automatic variables that point to other address spaces. 2559 // ISO/IEC TR 18037 S5.1.2 2560 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2561 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2562 return NewVD->setInvalidDecl(); 2563 } 2564 2565 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2566 && !NewVD->hasAttr<BlocksAttr>()) 2567 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2568 2569 bool isVM = T->isVariablyModifiedType(); 2570 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2571 NewVD->hasAttr<BlocksAttr>() || 2572 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2573 // However, this turns on the scope checker for everything with a variable 2574 // which may impact compile time. See if we can find a better solution 2575 // to this, perhaps only checking functions that contain gotos in C++? 2576 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2577 FunctionNeedsScopeChecking() = true; 2578 2579 if ((isVM && NewVD->hasLinkage()) || 2580 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2581 bool SizeIsNegative; 2582 QualType FixedTy = 2583 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2584 2585 if (FixedTy.isNull() && T->isVariableArrayType()) { 2586 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2587 // FIXME: This won't give the correct result for 2588 // int a[10][n]; 2589 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2590 2591 if (NewVD->isFileVarDecl()) 2592 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2593 << SizeRange; 2594 else if (NewVD->getStorageClass() == VarDecl::Static) 2595 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2596 << SizeRange; 2597 else 2598 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2599 << SizeRange; 2600 return NewVD->setInvalidDecl(); 2601 } 2602 2603 if (FixedTy.isNull()) { 2604 if (NewVD->isFileVarDecl()) 2605 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2606 else 2607 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2608 return NewVD->setInvalidDecl(); 2609 } 2610 2611 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2612 NewVD->setType(FixedTy); 2613 } 2614 2615 if (Previous.empty() && NewVD->isExternC()) { 2616 // Since we did not find anything by this name and we're declaring 2617 // an extern "C" variable, look for a non-visible extern "C" 2618 // declaration with the same name. 2619 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2620 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2621 if (Pos != LocallyScopedExternalDecls.end()) 2622 Previous.addDecl(Pos->second); 2623 } 2624 2625 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2626 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2627 << T; 2628 return NewVD->setInvalidDecl(); 2629 } 2630 2631 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2632 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2633 return NewVD->setInvalidDecl(); 2634 } 2635 2636 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2637 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2638 return NewVD->setInvalidDecl(); 2639 } 2640 2641 if (!Previous.empty()) { 2642 Redeclaration = true; 2643 MergeVarDecl(NewVD, Previous); 2644 } 2645} 2646 2647/// \brief Data used with FindOverriddenMethod 2648struct FindOverriddenMethodData { 2649 Sema *S; 2650 CXXMethodDecl *Method; 2651}; 2652 2653/// \brief Member lookup function that determines whether a given C++ 2654/// method overrides a method in a base class, to be used with 2655/// CXXRecordDecl::lookupInBases(). 2656static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2657 CXXBasePath &Path, 2658 void *UserData) { 2659 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2660 2661 FindOverriddenMethodData *Data 2662 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2663 2664 DeclarationName Name = Data->Method->getDeclName(); 2665 2666 // FIXME: Do we care about other names here too? 2667 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2668 // We really want to find the base class constructor here. 2669 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2670 CanQualType CT = Data->S->Context.getCanonicalType(T); 2671 2672 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2673 } 2674 2675 for (Path.Decls = BaseRecord->lookup(Name); 2676 Path.Decls.first != Path.Decls.second; 2677 ++Path.Decls.first) { 2678 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2679 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2680 return true; 2681 } 2682 } 2683 2684 return false; 2685} 2686 2687/// AddOverriddenMethods - See if a method overrides any in the base classes, 2688/// and if so, check that it's a valid override and remember it. 2689void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2690 // Look for virtual methods in base classes that this method might override. 2691 CXXBasePaths Paths; 2692 FindOverriddenMethodData Data; 2693 Data.Method = MD; 2694 Data.S = this; 2695 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2696 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2697 E = Paths.found_decls_end(); I != E; ++I) { 2698 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2699 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2700 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2701 !CheckOverridingFunctionAttributes(MD, OldMD)) 2702 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2703 } 2704 } 2705 } 2706} 2707 2708NamedDecl* 2709Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2710 QualType R, TypeSourceInfo *TInfo, 2711 LookupResult &Previous, 2712 MultiTemplateParamsArg TemplateParamLists, 2713 bool IsFunctionDefinition, bool &Redeclaration) { 2714 assert(R.getTypePtr()->isFunctionType()); 2715 2716 DeclarationName Name = GetNameForDeclarator(D); 2717 FunctionDecl::StorageClass SC = FunctionDecl::None; 2718 switch (D.getDeclSpec().getStorageClassSpec()) { 2719 default: assert(0 && "Unknown storage class!"); 2720 case DeclSpec::SCS_auto: 2721 case DeclSpec::SCS_register: 2722 case DeclSpec::SCS_mutable: 2723 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2724 diag::err_typecheck_sclass_func); 2725 D.setInvalidType(); 2726 break; 2727 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2728 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2729 case DeclSpec::SCS_static: { 2730 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2731 // C99 6.7.1p5: 2732 // The declaration of an identifier for a function that has 2733 // block scope shall have no explicit storage-class specifier 2734 // other than extern 2735 // See also (C++ [dcl.stc]p4). 2736 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2737 diag::err_static_block_func); 2738 SC = FunctionDecl::None; 2739 } else 2740 SC = FunctionDecl::Static; 2741 break; 2742 } 2743 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2744 } 2745 2746 if (D.getDeclSpec().isThreadSpecified()) 2747 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2748 2749 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2750 bool isInline = D.getDeclSpec().isInlineSpecified(); 2751 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2752 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2753 2754 // Check that the return type is not an abstract class type. 2755 // For record types, this is done by the AbstractClassUsageDiagnoser once 2756 // the class has been completely parsed. 2757 if (!DC->isRecord() && 2758 RequireNonAbstractType(D.getIdentifierLoc(), 2759 R->getAs<FunctionType>()->getResultType(), 2760 diag::err_abstract_type_in_decl, 2761 AbstractReturnType)) 2762 D.setInvalidType(); 2763 2764 // Do not allow returning a objc interface by-value. 2765 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2766 Diag(D.getIdentifierLoc(), 2767 diag::err_object_cannot_be_passed_returned_by_value) << 0 2768 << R->getAs<FunctionType>()->getResultType(); 2769 D.setInvalidType(); 2770 } 2771 2772 bool isVirtualOkay = false; 2773 FunctionDecl *NewFD; 2774 2775 if (isFriend) { 2776 // C++ [class.friend]p5 2777 // A function can be defined in a friend declaration of a 2778 // class . . . . Such a function is implicitly inline. 2779 isInline |= IsFunctionDefinition; 2780 } 2781 2782 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2783 // This is a C++ constructor declaration. 2784 assert(DC->isRecord() && 2785 "Constructors can only be declared in a member context"); 2786 2787 R = CheckConstructorDeclarator(D, R, SC); 2788 2789 // Create the new declaration 2790 NewFD = CXXConstructorDecl::Create(Context, 2791 cast<CXXRecordDecl>(DC), 2792 D.getIdentifierLoc(), Name, R, TInfo, 2793 isExplicit, isInline, 2794 /*isImplicitlyDeclared=*/false); 2795 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2796 // This is a C++ destructor declaration. 2797 if (DC->isRecord()) { 2798 R = CheckDestructorDeclarator(D, SC); 2799 2800 NewFD = CXXDestructorDecl::Create(Context, 2801 cast<CXXRecordDecl>(DC), 2802 D.getIdentifierLoc(), Name, R, 2803 isInline, 2804 /*isImplicitlyDeclared=*/false); 2805 NewFD->setTypeSourceInfo(TInfo); 2806 2807 isVirtualOkay = true; 2808 } else { 2809 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2810 2811 // Create a FunctionDecl to satisfy the function definition parsing 2812 // code path. 2813 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2814 Name, R, TInfo, SC, isInline, 2815 /*hasPrototype=*/true); 2816 D.setInvalidType(); 2817 } 2818 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2819 if (!DC->isRecord()) { 2820 Diag(D.getIdentifierLoc(), 2821 diag::err_conv_function_not_member); 2822 return 0; 2823 } 2824 2825 CheckConversionDeclarator(D, R, SC); 2826 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2827 D.getIdentifierLoc(), Name, R, TInfo, 2828 isInline, isExplicit); 2829 2830 isVirtualOkay = true; 2831 } else if (DC->isRecord()) { 2832 // If the of the function is the same as the name of the record, then this 2833 // must be an invalid constructor that has a return type. 2834 // (The parser checks for a return type and makes the declarator a 2835 // constructor if it has no return type). 2836 // must have an invalid constructor that has a return type 2837 if (Name.getAsIdentifierInfo() && 2838 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2839 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2840 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2841 << SourceRange(D.getIdentifierLoc()); 2842 return 0; 2843 } 2844 2845 bool isStatic = SC == FunctionDecl::Static; 2846 2847 // [class.free]p1: 2848 // Any allocation function for a class T is a static member 2849 // (even if not explicitly declared static). 2850 if (Name.getCXXOverloadedOperator() == OO_New || 2851 Name.getCXXOverloadedOperator() == OO_Array_New) 2852 isStatic = true; 2853 2854 // [class.free]p6 Any deallocation function for a class X is a static member 2855 // (even if not explicitly declared static). 2856 if (Name.getCXXOverloadedOperator() == OO_Delete || 2857 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2858 isStatic = true; 2859 2860 // This is a C++ method declaration. 2861 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2862 D.getIdentifierLoc(), Name, R, TInfo, 2863 isStatic, isInline); 2864 2865 isVirtualOkay = !isStatic; 2866 } else { 2867 // Determine whether the function was written with a 2868 // prototype. This true when: 2869 // - we're in C++ (where every function has a prototype), 2870 // - there is a prototype in the declarator, or 2871 // - the type R of the function is some kind of typedef or other reference 2872 // to a type name (which eventually refers to a function type). 2873 bool HasPrototype = 2874 getLangOptions().CPlusPlus || 2875 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2876 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2877 2878 NewFD = FunctionDecl::Create(Context, DC, 2879 D.getIdentifierLoc(), 2880 Name, R, TInfo, SC, isInline, HasPrototype); 2881 } 2882 2883 if (D.isInvalidType()) 2884 NewFD->setInvalidDecl(); 2885 2886 SetNestedNameSpecifier(NewFD, D); 2887 2888 // Set the lexical context. If the declarator has a C++ 2889 // scope specifier, or is the object of a friend declaration, the 2890 // lexical context will be different from the semantic context. 2891 NewFD->setLexicalDeclContext(CurContext); 2892 2893 // Match up the template parameter lists with the scope specifier, then 2894 // determine whether we have a template or a template specialization. 2895 FunctionTemplateDecl *FunctionTemplate = 0; 2896 bool isExplicitSpecialization = false; 2897 bool isFunctionTemplateSpecialization = false; 2898 if (TemplateParameterList *TemplateParams 2899 = MatchTemplateParametersToScopeSpecifier( 2900 D.getDeclSpec().getSourceRange().getBegin(), 2901 D.getCXXScopeSpec(), 2902 (TemplateParameterList**)TemplateParamLists.get(), 2903 TemplateParamLists.size(), 2904 isExplicitSpecialization)) { 2905 if (TemplateParams->size() > 0) { 2906 // This is a function template 2907 2908 // Check that we can declare a template here. 2909 if (CheckTemplateDeclScope(S, TemplateParams)) 2910 return 0; 2911 2912 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2913 NewFD->getLocation(), 2914 Name, TemplateParams, 2915 NewFD); 2916 FunctionTemplate->setLexicalDeclContext(CurContext); 2917 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2918 } else { 2919 // This is a function template specialization. 2920 isFunctionTemplateSpecialization = true; 2921 2922 // C++0x [temp.expl.spec]p20 forbids "template<> void foo(int);". 2923 if (isFriend && isFunctionTemplateSpecialization) { 2924 // We want to remove the "template<>", found here. 2925 SourceRange RemoveRange = TemplateParams->getSourceRange(); 2926 2927 // If we remove the template<> and the name is not a 2928 // template-id, we're actually silently creating a problem: 2929 // the friend declaration will refer to an untemplated decl, 2930 // and clearly the user wants a template specialization. So 2931 // we need to insert '<>' after the name. 2932 SourceLocation InsertLoc; 2933 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 2934 InsertLoc = D.getName().getSourceRange().getEnd(); 2935 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 2936 } 2937 2938 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 2939 << Name << RemoveRange 2940 << CodeModificationHint::CreateRemoval(RemoveRange) 2941 << CodeModificationHint::CreateInsertion(InsertLoc, "<>"); 2942 } 2943 } 2944 2945 // FIXME: Free this memory properly. 2946 TemplateParamLists.release(); 2947 } 2948 2949 // C++ [dcl.fct.spec]p5: 2950 // The virtual specifier shall only be used in declarations of 2951 // nonstatic class member functions that appear within a 2952 // member-specification of a class declaration; see 10.3. 2953 // 2954 if (isVirtual && !NewFD->isInvalidDecl()) { 2955 if (!isVirtualOkay) { 2956 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2957 diag::err_virtual_non_function); 2958 } else if (!CurContext->isRecord()) { 2959 // 'virtual' was specified outside of the class. 2960 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2961 << CodeModificationHint::CreateRemoval( 2962 D.getDeclSpec().getVirtualSpecLoc()); 2963 } else { 2964 // Okay: Add virtual to the method. 2965 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2966 CurClass->setMethodAsVirtual(NewFD); 2967 } 2968 } 2969 2970 // C++ [dcl.fct.spec]p6: 2971 // The explicit specifier shall be used only in the declaration of a 2972 // constructor or conversion function within its class definition; see 12.3.1 2973 // and 12.3.2. 2974 if (isExplicit && !NewFD->isInvalidDecl()) { 2975 if (!CurContext->isRecord()) { 2976 // 'explicit' was specified outside of the class. 2977 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2978 diag::err_explicit_out_of_class) 2979 << CodeModificationHint::CreateRemoval( 2980 D.getDeclSpec().getExplicitSpecLoc()); 2981 } else if (!isa<CXXConstructorDecl>(NewFD) && 2982 !isa<CXXConversionDecl>(NewFD)) { 2983 // 'explicit' was specified on a function that wasn't a constructor 2984 // or conversion function. 2985 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2986 diag::err_explicit_non_ctor_or_conv_function) 2987 << CodeModificationHint::CreateRemoval( 2988 D.getDeclSpec().getExplicitSpecLoc()); 2989 } 2990 } 2991 2992 // Filter out previous declarations that don't match the scope. 2993 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2994 2995 if (isFriend) { 2996 // DC is the namespace in which the function is being declared. 2997 assert((DC->isFileContext() || !Previous.empty()) && 2998 "previously-undeclared friend function being created " 2999 "in a non-namespace context"); 3000 3001 // For now, claim that the objects have no previous declaration. 3002 if (FunctionTemplate) { 3003 FunctionTemplate->setObjectOfFriendDecl(false); 3004 FunctionTemplate->setAccess(AS_public); 3005 } else { 3006 NewFD->setObjectOfFriendDecl(false); 3007 } 3008 3009 NewFD->setAccess(AS_public); 3010 } 3011 3012 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3013 !CurContext->isRecord()) { 3014 // C++ [class.static]p1: 3015 // A data or function member of a class may be declared static 3016 // in a class definition, in which case it is a static member of 3017 // the class. 3018 3019 // Complain about the 'static' specifier if it's on an out-of-line 3020 // member function definition. 3021 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3022 diag::err_static_out_of_line) 3023 << CodeModificationHint::CreateRemoval( 3024 D.getDeclSpec().getStorageClassSpecLoc()); 3025 } 3026 3027 // Handle GNU asm-label extension (encoded as an attribute). 3028 if (Expr *E = (Expr*) D.getAsmLabel()) { 3029 // The parser guarantees this is a string. 3030 StringLiteral *SE = cast<StringLiteral>(E); 3031 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3032 } 3033 3034 // Copy the parameter declarations from the declarator D to the function 3035 // declaration NewFD, if they are available. First scavenge them into Params. 3036 llvm::SmallVector<ParmVarDecl*, 16> Params; 3037 if (D.getNumTypeObjects() > 0) { 3038 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3039 3040 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3041 // function that takes no arguments, not a function that takes a 3042 // single void argument. 3043 // We let through "const void" here because Sema::GetTypeForDeclarator 3044 // already checks for that case. 3045 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3046 FTI.ArgInfo[0].Param && 3047 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3048 // Empty arg list, don't push any params. 3049 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3050 3051 // In C++, the empty parameter-type-list must be spelled "void"; a 3052 // typedef of void is not permitted. 3053 if (getLangOptions().CPlusPlus && 3054 Param->getType().getUnqualifiedType() != Context.VoidTy) 3055 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3056 // FIXME: Leaks decl? 3057 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3058 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3059 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3060 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3061 Param->setDeclContext(NewFD); 3062 Params.push_back(Param); 3063 } 3064 } 3065 3066 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3067 // When we're declaring a function with a typedef, typeof, etc as in the 3068 // following example, we'll need to synthesize (unnamed) 3069 // parameters for use in the declaration. 3070 // 3071 // @code 3072 // typedef void fn(int); 3073 // fn f; 3074 // @endcode 3075 3076 // Synthesize a parameter for each argument type. 3077 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3078 AE = FT->arg_type_end(); AI != AE; ++AI) { 3079 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 3080 SourceLocation(), 0, 3081 *AI, /*TInfo=*/0, 3082 VarDecl::None, 0); 3083 Param->setImplicit(); 3084 Params.push_back(Param); 3085 } 3086 } else { 3087 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3088 "Should not need args for typedef of non-prototype fn"); 3089 } 3090 // Finally, we know we have the right number of parameters, install them. 3091 NewFD->setParams(Params.data(), Params.size()); 3092 3093 // If the declarator is a template-id, translate the parser's template 3094 // argument list into our AST format. 3095 bool HasExplicitTemplateArgs = false; 3096 TemplateArgumentListInfo TemplateArgs; 3097 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3098 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3099 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3100 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3101 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3102 TemplateId->getTemplateArgs(), 3103 TemplateId->NumArgs); 3104 translateTemplateArguments(TemplateArgsPtr, 3105 TemplateArgs); 3106 TemplateArgsPtr.release(); 3107 3108 HasExplicitTemplateArgs = true; 3109 3110 if (FunctionTemplate) { 3111 // FIXME: Diagnose function template with explicit template 3112 // arguments. 3113 HasExplicitTemplateArgs = false; 3114 } else if (!isFunctionTemplateSpecialization && 3115 !D.getDeclSpec().isFriendSpecified()) { 3116 // We have encountered something that the user meant to be a 3117 // specialization (because it has explicitly-specified template 3118 // arguments) but that was not introduced with a "template<>" (or had 3119 // too few of them). 3120 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3121 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3122 << CodeModificationHint::CreateInsertion( 3123 D.getDeclSpec().getSourceRange().getBegin(), 3124 "template<> "); 3125 isFunctionTemplateSpecialization = true; 3126 } else { 3127 // "friend void foo<>(int);" is an implicit specialization decl. 3128 isFunctionTemplateSpecialization = true; 3129 } 3130 } 3131 3132 if (isFunctionTemplateSpecialization) { 3133 if (isFriend && NewFD->getType()->isDependentType()) { 3134 // FIXME: When we see a friend of a function template 3135 // specialization with a dependent type, we can't match it now; 3136 // for now, we just drop it, until we have a reasonable way to 3137 // represent the parsed-but-not-matched friend function template 3138 // specialization in the AST. 3139 return 0; 3140 } else if (CheckFunctionTemplateSpecialization(NewFD, 3141 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3142 Previous)) 3143 NewFD->setInvalidDecl(); 3144 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3145 CheckMemberSpecialization(NewFD, Previous)) 3146 NewFD->setInvalidDecl(); 3147 3148 // Perform semantic checking on the function declaration. 3149 bool OverloadableAttrRequired = false; // FIXME: HACK! 3150 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3151 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3152 3153 assert((NewFD->isInvalidDecl() || !Redeclaration || 3154 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3155 "previous declaration set still overloaded"); 3156 3157 if (isFriend && Redeclaration) { 3158 AccessSpecifier Access = NewFD->getPreviousDeclaration()->getAccess(); 3159 if (FunctionTemplate) { 3160 FunctionTemplate->setObjectOfFriendDecl(true); 3161 FunctionTemplate->setAccess(Access); 3162 } else { 3163 NewFD->setObjectOfFriendDecl(true); 3164 } 3165 NewFD->setAccess(Access); 3166 } 3167 3168 // If we have a function template, check the template parameter 3169 // list. This will check and merge default template arguments. 3170 if (FunctionTemplate) { 3171 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3172 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3173 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3174 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3175 : TPC_FunctionTemplate); 3176 } 3177 3178 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3179 // Fake up an access specifier if it's supposed to be a class member. 3180 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3181 NewFD->setAccess(AS_public); 3182 3183 // An out-of-line member function declaration must also be a 3184 // definition (C++ [dcl.meaning]p1). 3185 // Note that this is not the case for explicit specializations of 3186 // function templates or member functions of class templates, per 3187 // C++ [temp.expl.spec]p2. 3188 if (!IsFunctionDefinition && !isFriend && 3189 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3190 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3191 << D.getCXXScopeSpec().getRange(); 3192 NewFD->setInvalidDecl(); 3193 } else if (!Redeclaration && 3194 !(isFriend && CurContext->isDependentContext())) { 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 3272 // Keep track of static, non-inlined function definitions that 3273 // have not been used. We will warn later. 3274 // FIXME: Also include static functions declared but not defined. 3275 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3276 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3277 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>()) 3278 UnusedStaticFuncs.push_back(NewFD); 3279 3280 return NewFD; 3281} 3282 3283/// \brief Perform semantic checking of a new function declaration. 3284/// 3285/// Performs semantic analysis of the new function declaration 3286/// NewFD. This routine performs all semantic checking that does not 3287/// require the actual declarator involved in the declaration, and is 3288/// used both for the declaration of functions as they are parsed 3289/// (called via ActOnDeclarator) and for the declaration of functions 3290/// that have been instantiated via C++ template instantiation (called 3291/// via InstantiateDecl). 3292/// 3293/// \param IsExplicitSpecialiation whether this new function declaration is 3294/// an explicit specialization of the previous declaration. 3295/// 3296/// This sets NewFD->isInvalidDecl() to true if there was an error. 3297void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3298 LookupResult &Previous, 3299 bool IsExplicitSpecialization, 3300 bool &Redeclaration, 3301 bool &OverloadableAttrRequired) { 3302 // If NewFD is already known erroneous, don't do any of this checking. 3303 if (NewFD->isInvalidDecl()) 3304 return; 3305 3306 if (NewFD->getResultType()->isVariablyModifiedType()) { 3307 // Functions returning a variably modified type violate C99 6.7.5.2p2 3308 // because all functions have linkage. 3309 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3310 return NewFD->setInvalidDecl(); 3311 } 3312 3313 if (NewFD->isMain()) 3314 CheckMain(NewFD); 3315 3316 // Check for a previous declaration of this name. 3317 if (Previous.empty() && NewFD->isExternC()) { 3318 // Since we did not find anything by this name and we're declaring 3319 // an extern "C" function, look for a non-visible extern "C" 3320 // declaration with the same name. 3321 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3322 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3323 if (Pos != LocallyScopedExternalDecls.end()) 3324 Previous.addDecl(Pos->second); 3325 } 3326 3327 // Merge or overload the declaration with an existing declaration of 3328 // the same name, if appropriate. 3329 if (!Previous.empty()) { 3330 // Determine whether NewFD is an overload of PrevDecl or 3331 // a declaration that requires merging. If it's an overload, 3332 // there's no more work to do here; we'll just add the new 3333 // function to the scope. 3334 3335 NamedDecl *OldDecl = 0; 3336 if (!AllowOverloadingOfFunction(Previous, Context)) { 3337 Redeclaration = true; 3338 OldDecl = Previous.getFoundDecl(); 3339 } else { 3340 if (!getLangOptions().CPlusPlus) { 3341 OverloadableAttrRequired = true; 3342 3343 // Functions marked "overloadable" must have a prototype (that 3344 // we can't get through declaration merging). 3345 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3346 Diag(NewFD->getLocation(), 3347 diag::err_attribute_overloadable_no_prototype) 3348 << NewFD; 3349 Redeclaration = true; 3350 3351 // Turn this into a variadic function with no parameters. 3352 QualType R = Context.getFunctionType( 3353 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3354 0, 0, true, 0, false, false, 0, 0, false, CC_Default); 3355 NewFD->setType(R); 3356 return NewFD->setInvalidDecl(); 3357 } 3358 } 3359 3360 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3361 case Ovl_Match: 3362 Redeclaration = true; 3363 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3364 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3365 Redeclaration = false; 3366 } 3367 break; 3368 3369 case Ovl_NonFunction: 3370 Redeclaration = true; 3371 break; 3372 3373 case Ovl_Overload: 3374 Redeclaration = false; 3375 break; 3376 } 3377 } 3378 3379 if (Redeclaration) { 3380 // NewFD and OldDecl represent declarations that need to be 3381 // merged. 3382 if (MergeFunctionDecl(NewFD, OldDecl)) 3383 return NewFD->setInvalidDecl(); 3384 3385 Previous.clear(); 3386 Previous.addDecl(OldDecl); 3387 3388 if (FunctionTemplateDecl *OldTemplateDecl 3389 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3390 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3391 FunctionTemplateDecl *NewTemplateDecl 3392 = NewFD->getDescribedFunctionTemplate(); 3393 assert(NewTemplateDecl && "Template/non-template mismatch"); 3394 if (CXXMethodDecl *Method 3395 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3396 Method->setAccess(OldTemplateDecl->getAccess()); 3397 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3398 } 3399 3400 // If this is an explicit specialization of a member that is a function 3401 // template, mark it as a member specialization. 3402 if (IsExplicitSpecialization && 3403 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3404 NewTemplateDecl->setMemberSpecialization(); 3405 assert(OldTemplateDecl->isMemberSpecialization()); 3406 } 3407 } else { 3408 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3409 NewFD->setAccess(OldDecl->getAccess()); 3410 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3411 } 3412 } 3413 } 3414 3415 // Semantic checking for this function declaration (in isolation). 3416 if (getLangOptions().CPlusPlus) { 3417 // C++-specific checks. 3418 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3419 CheckConstructor(Constructor); 3420 } else if (CXXDestructorDecl *Destructor = 3421 dyn_cast<CXXDestructorDecl>(NewFD)) { 3422 CXXRecordDecl *Record = Destructor->getParent(); 3423 QualType ClassType = Context.getTypeDeclType(Record); 3424 3425 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3426 // type is dependent? Both gcc and edg can handle that. 3427 if (!ClassType->isDependentType()) { 3428 DeclarationName Name 3429 = Context.DeclarationNames.getCXXDestructorName( 3430 Context.getCanonicalType(ClassType)); 3431 if (NewFD->getDeclName() != Name) { 3432 Diag(NewFD->getLocation(), diag::err_destructor_name); 3433 return NewFD->setInvalidDecl(); 3434 } 3435 } 3436 3437 Record->setUserDeclaredDestructor(true); 3438 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3439 // user-defined destructor. 3440 Record->setPOD(false); 3441 3442 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3443 // declared destructor. 3444 // FIXME: C++0x: don't do this for "= default" destructors 3445 Record->setHasTrivialDestructor(false); 3446 } else if (CXXConversionDecl *Conversion 3447 = dyn_cast<CXXConversionDecl>(NewFD)) { 3448 ActOnConversionDeclarator(Conversion); 3449 } 3450 3451 // Find any virtual functions that this function overrides. 3452 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3453 if (!Method->isFunctionTemplateSpecialization() && 3454 !Method->getDescribedFunctionTemplate()) 3455 AddOverriddenMethods(Method->getParent(), Method); 3456 } 3457 3458 // Additional checks for the destructor; make sure we do this after we 3459 // figure out whether the destructor is virtual. 3460 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3461 if (!Destructor->getParent()->isDependentType()) 3462 CheckDestructor(Destructor); 3463 3464 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3465 if (NewFD->isOverloadedOperator() && 3466 CheckOverloadedOperatorDeclaration(NewFD)) 3467 return NewFD->setInvalidDecl(); 3468 3469 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3470 if (NewFD->getLiteralIdentifier() && 3471 CheckLiteralOperatorDeclaration(NewFD)) 3472 return NewFD->setInvalidDecl(); 3473 3474 // In C++, check default arguments now that we have merged decls. Unless 3475 // the lexical context is the class, because in this case this is done 3476 // during delayed parsing anyway. 3477 if (!CurContext->isRecord()) 3478 CheckCXXDefaultArguments(NewFD); 3479 } 3480} 3481 3482void Sema::CheckMain(FunctionDecl* FD) { 3483 // C++ [basic.start.main]p3: A program that declares main to be inline 3484 // or static is ill-formed. 3485 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3486 // shall not appear in a declaration of main. 3487 // static main is not an error under C99, but we should warn about it. 3488 bool isInline = FD->isInlineSpecified(); 3489 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3490 if (isInline || isStatic) { 3491 unsigned diagID = diag::warn_unusual_main_decl; 3492 if (isInline || getLangOptions().CPlusPlus) 3493 diagID = diag::err_unusual_main_decl; 3494 3495 int which = isStatic + (isInline << 1) - 1; 3496 Diag(FD->getLocation(), diagID) << which; 3497 } 3498 3499 QualType T = FD->getType(); 3500 assert(T->isFunctionType() && "function decl is not of function type"); 3501 const FunctionType* FT = T->getAs<FunctionType>(); 3502 3503 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3504 // TODO: add a replacement fixit to turn the return type into 'int'. 3505 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3506 FD->setInvalidDecl(true); 3507 } 3508 3509 // Treat protoless main() as nullary. 3510 if (isa<FunctionNoProtoType>(FT)) return; 3511 3512 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3513 unsigned nparams = FTP->getNumArgs(); 3514 assert(FD->getNumParams() == nparams); 3515 3516 bool HasExtraParameters = (nparams > 3); 3517 3518 // Darwin passes an undocumented fourth argument of type char**. If 3519 // other platforms start sprouting these, the logic below will start 3520 // getting shifty. 3521 if (nparams == 4 && 3522 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3523 HasExtraParameters = false; 3524 3525 if (HasExtraParameters) { 3526 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3527 FD->setInvalidDecl(true); 3528 nparams = 3; 3529 } 3530 3531 // FIXME: a lot of the following diagnostics would be improved 3532 // if we had some location information about types. 3533 3534 QualType CharPP = 3535 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3536 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3537 3538 for (unsigned i = 0; i < nparams; ++i) { 3539 QualType AT = FTP->getArgType(i); 3540 3541 bool mismatch = true; 3542 3543 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3544 mismatch = false; 3545 else if (Expected[i] == CharPP) { 3546 // As an extension, the following forms are okay: 3547 // char const ** 3548 // char const * const * 3549 // char * const * 3550 3551 QualifierCollector qs; 3552 const PointerType* PT; 3553 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3554 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3555 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3556 qs.removeConst(); 3557 mismatch = !qs.empty(); 3558 } 3559 } 3560 3561 if (mismatch) { 3562 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3563 // TODO: suggest replacing given type with expected type 3564 FD->setInvalidDecl(true); 3565 } 3566 } 3567 3568 if (nparams == 1 && !FD->isInvalidDecl()) { 3569 Diag(FD->getLocation(), diag::warn_main_one_arg); 3570 } 3571} 3572 3573bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3574 // FIXME: Need strict checking. In C89, we need to check for 3575 // any assignment, increment, decrement, function-calls, or 3576 // commas outside of a sizeof. In C99, it's the same list, 3577 // except that the aforementioned are allowed in unevaluated 3578 // expressions. Everything else falls under the 3579 // "may accept other forms of constant expressions" exception. 3580 // (We never end up here for C++, so the constant expression 3581 // rules there don't matter.) 3582 if (Init->isConstantInitializer(Context)) 3583 return false; 3584 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3585 << Init->getSourceRange(); 3586 return true; 3587} 3588 3589void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3590 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3591} 3592 3593/// AddInitializerToDecl - Adds the initializer Init to the 3594/// declaration dcl. If DirectInit is true, this is C++ direct 3595/// initialization rather than copy initialization. 3596void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3597 Decl *RealDecl = dcl.getAs<Decl>(); 3598 // If there is no declaration, there was an error parsing it. Just ignore 3599 // the initializer. 3600 if (RealDecl == 0) 3601 return; 3602 3603 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3604 // With declarators parsed the way they are, the parser cannot 3605 // distinguish between a normal initializer and a pure-specifier. 3606 // Thus this grotesque test. 3607 IntegerLiteral *IL; 3608 Expr *Init = static_cast<Expr *>(init.get()); 3609 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3610 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3611 CheckPureMethod(Method, Init->getSourceRange()); 3612 else { 3613 Diag(Method->getLocation(), diag::err_member_function_initialization) 3614 << Method->getDeclName() << Init->getSourceRange(); 3615 Method->setInvalidDecl(); 3616 } 3617 return; 3618 } 3619 3620 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3621 if (!VDecl) { 3622 if (getLangOptions().CPlusPlus && 3623 RealDecl->getLexicalDeclContext()->isRecord() && 3624 isa<NamedDecl>(RealDecl)) 3625 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3626 << cast<NamedDecl>(RealDecl)->getDeclName(); 3627 else 3628 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3629 RealDecl->setInvalidDecl(); 3630 return; 3631 } 3632 3633 // A definition must end up with a complete type, which means it must be 3634 // complete with the restriction that an array type might be completed by the 3635 // initializer; note that later code assumes this restriction. 3636 QualType BaseDeclType = VDecl->getType(); 3637 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3638 BaseDeclType = Array->getElementType(); 3639 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3640 diag::err_typecheck_decl_incomplete_type)) { 3641 RealDecl->setInvalidDecl(); 3642 return; 3643 } 3644 3645 // The variable can not have an abstract class type. 3646 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3647 diag::err_abstract_type_in_decl, 3648 AbstractVariableType)) 3649 VDecl->setInvalidDecl(); 3650 3651 const VarDecl *Def; 3652 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3653 Diag(VDecl->getLocation(), diag::err_redefinition) 3654 << VDecl->getDeclName(); 3655 Diag(Def->getLocation(), diag::note_previous_definition); 3656 VDecl->setInvalidDecl(); 3657 return; 3658 } 3659 3660 // Take ownership of the expression, now that we're sure we have somewhere 3661 // to put it. 3662 Expr *Init = init.takeAs<Expr>(); 3663 assert(Init && "missing initializer"); 3664 3665 // Capture the variable that is being initialized and the style of 3666 // initialization. 3667 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3668 3669 // FIXME: Poor source location information. 3670 InitializationKind Kind 3671 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3672 Init->getLocStart(), 3673 Init->getLocEnd()) 3674 : InitializationKind::CreateCopy(VDecl->getLocation(), 3675 Init->getLocStart()); 3676 3677 // Get the decls type and save a reference for later, since 3678 // CheckInitializerTypes may change it. 3679 QualType DclT = VDecl->getType(), SavT = DclT; 3680 if (VDecl->isBlockVarDecl()) { 3681 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3682 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3683 VDecl->setInvalidDecl(); 3684 } else if (!VDecl->isInvalidDecl()) { 3685 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3686 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3687 MultiExprArg(*this, (void**)&Init, 1), 3688 &DclT); 3689 if (Result.isInvalid()) { 3690 VDecl->setInvalidDecl(); 3691 return; 3692 } 3693 3694 Init = Result.takeAs<Expr>(); 3695 3696 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3697 // Don't check invalid declarations to avoid emitting useless diagnostics. 3698 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3699 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3700 CheckForConstantInitializer(Init, DclT); 3701 } 3702 } 3703 } else if (VDecl->isStaticDataMember() && 3704 VDecl->getLexicalDeclContext()->isRecord()) { 3705 // This is an in-class initialization for a static data member, e.g., 3706 // 3707 // struct S { 3708 // static const int value = 17; 3709 // }; 3710 3711 // Attach the initializer 3712 VDecl->setInit(Init); 3713 3714 // C++ [class.mem]p4: 3715 // A member-declarator can contain a constant-initializer only 3716 // if it declares a static member (9.4) of const integral or 3717 // const enumeration type, see 9.4.2. 3718 QualType T = VDecl->getType(); 3719 if (!T->isDependentType() && 3720 (!Context.getCanonicalType(T).isConstQualified() || 3721 !T->isIntegralType())) { 3722 Diag(VDecl->getLocation(), diag::err_member_initialization) 3723 << VDecl->getDeclName() << Init->getSourceRange(); 3724 VDecl->setInvalidDecl(); 3725 } else { 3726 // C++ [class.static.data]p4: 3727 // If a static data member is of const integral or const 3728 // enumeration type, its declaration in the class definition 3729 // can specify a constant-initializer which shall be an 3730 // integral constant expression (5.19). 3731 if (!Init->isTypeDependent() && 3732 !Init->getType()->isIntegralType()) { 3733 // We have a non-dependent, non-integral or enumeration type. 3734 Diag(Init->getSourceRange().getBegin(), 3735 diag::err_in_class_initializer_non_integral_type) 3736 << Init->getType() << Init->getSourceRange(); 3737 VDecl->setInvalidDecl(); 3738 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3739 // Check whether the expression is a constant expression. 3740 llvm::APSInt Value; 3741 SourceLocation Loc; 3742 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3743 Diag(Loc, diag::err_in_class_initializer_non_constant) 3744 << Init->getSourceRange(); 3745 VDecl->setInvalidDecl(); 3746 } else if (!VDecl->getType()->isDependentType()) 3747 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3748 } 3749 } 3750 } else if (VDecl->isFileVarDecl()) { 3751 if (VDecl->getStorageClass() == VarDecl::Extern) 3752 Diag(VDecl->getLocation(), diag::warn_extern_init); 3753 if (!VDecl->isInvalidDecl()) { 3754 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3755 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3756 MultiExprArg(*this, (void**)&Init, 1), 3757 &DclT); 3758 if (Result.isInvalid()) { 3759 VDecl->setInvalidDecl(); 3760 return; 3761 } 3762 3763 Init = Result.takeAs<Expr>(); 3764 } 3765 3766 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3767 // Don't check invalid declarations to avoid emitting useless diagnostics. 3768 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3769 // C99 6.7.8p4. All file scoped initializers need to be constant. 3770 CheckForConstantInitializer(Init, DclT); 3771 } 3772 } 3773 // If the type changed, it means we had an incomplete type that was 3774 // completed by the initializer. For example: 3775 // int ary[] = { 1, 3, 5 }; 3776 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3777 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3778 VDecl->setType(DclT); 3779 Init->setType(DclT); 3780 } 3781 3782 Init = MaybeCreateCXXExprWithTemporaries(Init); 3783 // Attach the initializer to the decl. 3784 VDecl->setInit(Init); 3785 3786 if (getLangOptions().CPlusPlus) { 3787 // Make sure we mark the destructor as used if necessary. 3788 QualType InitType = VDecl->getType(); 3789 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3790 InitType = Context.getBaseElementType(Array); 3791 if (const RecordType *Record = InitType->getAs<RecordType>()) 3792 FinalizeVarWithDestructor(VDecl, Record); 3793 } 3794 3795 return; 3796} 3797 3798void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3799 bool TypeContainsUndeducedAuto) { 3800 Decl *RealDecl = dcl.getAs<Decl>(); 3801 3802 // If there is no declaration, there was an error parsing it. Just ignore it. 3803 if (RealDecl == 0) 3804 return; 3805 3806 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3807 QualType Type = Var->getType(); 3808 3809 // C++0x [dcl.spec.auto]p3 3810 if (TypeContainsUndeducedAuto) { 3811 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3812 << Var->getDeclName() << Type; 3813 Var->setInvalidDecl(); 3814 return; 3815 } 3816 3817 switch (Var->isThisDeclarationADefinition()) { 3818 case VarDecl::Definition: 3819 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 3820 break; 3821 3822 // We have an out-of-line definition of a static data member 3823 // that has an in-class initializer, so we type-check this like 3824 // a declaration. 3825 // 3826 // Fall through 3827 3828 case VarDecl::DeclarationOnly: 3829 // It's only a declaration. 3830 3831 // Block scope. C99 6.7p7: If an identifier for an object is 3832 // declared with no linkage (C99 6.2.2p6), the type for the 3833 // object shall be complete. 3834 if (!Type->isDependentType() && Var->isBlockVarDecl() && 3835 !Var->getLinkage() && !Var->isInvalidDecl() && 3836 RequireCompleteType(Var->getLocation(), Type, 3837 diag::err_typecheck_decl_incomplete_type)) 3838 Var->setInvalidDecl(); 3839 3840 // Make sure that the type is not abstract. 3841 if (!Type->isDependentType() && !Var->isInvalidDecl() && 3842 RequireNonAbstractType(Var->getLocation(), Type, 3843 diag::err_abstract_type_in_decl, 3844 AbstractVariableType)) 3845 Var->setInvalidDecl(); 3846 return; 3847 3848 case VarDecl::TentativeDefinition: 3849 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3850 // object that has file scope without an initializer, and without a 3851 // storage-class specifier or with the storage-class specifier "static", 3852 // constitutes a tentative definition. Note: A tentative definition with 3853 // external linkage is valid (C99 6.2.2p5). 3854 if (!Var->isInvalidDecl()) { 3855 if (const IncompleteArrayType *ArrayT 3856 = Context.getAsIncompleteArrayType(Type)) { 3857 if (RequireCompleteType(Var->getLocation(), 3858 ArrayT->getElementType(), 3859 diag::err_illegal_decl_array_incomplete_type)) 3860 Var->setInvalidDecl(); 3861 } else if (Var->getStorageClass() == VarDecl::Static) { 3862 // C99 6.9.2p3: If the declaration of an identifier for an object is 3863 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3864 // declared type shall not be an incomplete type. 3865 // NOTE: code such as the following 3866 // static struct s; 3867 // struct s { int a; }; 3868 // is accepted by gcc. Hence here we issue a warning instead of 3869 // an error and we do not invalidate the static declaration. 3870 // NOTE: to avoid multiple warnings, only check the first declaration. 3871 if (Var->getPreviousDeclaration() == 0) 3872 RequireCompleteType(Var->getLocation(), Type, 3873 diag::ext_typecheck_decl_incomplete_type); 3874 } 3875 } 3876 3877 // Record the tentative definition; we're done. 3878 if (!Var->isInvalidDecl()) 3879 TentativeDefinitions.push_back(Var); 3880 return; 3881 } 3882 3883 // Provide a specific diagnostic for uninitialized variable 3884 // definitions with incomplete array type. 3885 if (Type->isIncompleteArrayType()) { 3886 Diag(Var->getLocation(), 3887 diag::err_typecheck_incomplete_array_needs_initializer); 3888 Var->setInvalidDecl(); 3889 return; 3890 } 3891 3892 // Provide a specific diagnostic for uninitialized variable 3893 // definitions with reference type. 3894 if (Type->isReferenceType()) { 3895 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3896 << Var->getDeclName() 3897 << SourceRange(Var->getLocation(), Var->getLocation()); 3898 Var->setInvalidDecl(); 3899 return; 3900 } 3901 3902 // Do not attempt to type-check the default initializer for a 3903 // variable with dependent type. 3904 if (Type->isDependentType()) 3905 return; 3906 3907 if (Var->isInvalidDecl()) 3908 return; 3909 3910 if (RequireCompleteType(Var->getLocation(), 3911 Context.getBaseElementType(Type), 3912 diag::err_typecheck_decl_incomplete_type)) { 3913 Var->setInvalidDecl(); 3914 return; 3915 } 3916 3917 // The variable can not have an abstract class type. 3918 if (RequireNonAbstractType(Var->getLocation(), Type, 3919 diag::err_abstract_type_in_decl, 3920 AbstractVariableType)) { 3921 Var->setInvalidDecl(); 3922 return; 3923 } 3924 3925 const RecordType *Record 3926 = Context.getBaseElementType(Type)->getAs<RecordType>(); 3927 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 3928 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 3929 // C++03 [dcl.init]p9: 3930 // If no initializer is specified for an object, and the 3931 // object is of (possibly cv-qualified) non-POD class type (or 3932 // array thereof), the object shall be default-initialized; if 3933 // the object is of const-qualified type, the underlying class 3934 // type shall have a user-declared default 3935 // constructor. Otherwise, if no initializer is specified for 3936 // a non- static object, the object and its subobjects, if 3937 // any, have an indeterminate initial value); if the object 3938 // or any of its subobjects are of const-qualified type, the 3939 // program is ill-formed. 3940 // FIXME: DPG thinks it is very fishy that C++0x disables this. 3941 } else { 3942 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 3943 InitializationKind Kind 3944 = InitializationKind::CreateDefault(Var->getLocation()); 3945 3946 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 3947 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 3948 MultiExprArg(*this, 0, 0)); 3949 if (Init.isInvalid()) 3950 Var->setInvalidDecl(); 3951 else if (Init.get()) 3952 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 3953 } 3954 3955 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 3956 FinalizeVarWithDestructor(Var, Record); 3957 } 3958} 3959 3960Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3961 DeclPtrTy *Group, 3962 unsigned NumDecls) { 3963 llvm::SmallVector<Decl*, 8> Decls; 3964 3965 if (DS.isTypeSpecOwned()) 3966 Decls.push_back((Decl*)DS.getTypeRep()); 3967 3968 for (unsigned i = 0; i != NumDecls; ++i) 3969 if (Decl *D = Group[i].getAs<Decl>()) 3970 Decls.push_back(D); 3971 3972 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3973 Decls.data(), Decls.size())); 3974} 3975 3976 3977/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3978/// to introduce parameters into function prototype scope. 3979Sema::DeclPtrTy 3980Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3981 const DeclSpec &DS = D.getDeclSpec(); 3982 3983 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3984 VarDecl::StorageClass StorageClass = VarDecl::None; 3985 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3986 StorageClass = VarDecl::Register; 3987 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3988 Diag(DS.getStorageClassSpecLoc(), 3989 diag::err_invalid_storage_class_in_func_decl); 3990 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3991 } 3992 3993 if (D.getDeclSpec().isThreadSpecified()) 3994 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3995 3996 DiagnoseFunctionSpecifiers(D); 3997 3998 // Check that there are no default arguments inside the type of this 3999 // parameter (C++ only). 4000 if (getLangOptions().CPlusPlus) 4001 CheckExtraCXXDefaultArguments(D); 4002 4003 TypeSourceInfo *TInfo = 0; 4004 TagDecl *OwnedDecl = 0; 4005 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 4006 4007 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4008 // C++ [dcl.fct]p6: 4009 // Types shall not be defined in return or parameter types. 4010 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4011 << Context.getTypeDeclType(OwnedDecl); 4012 } 4013 4014 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4015 IdentifierInfo *II = D.getIdentifier(); 4016 if (II) { 4017 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4018 ForRedeclaration); 4019 LookupName(R, S); 4020 if (R.isSingleResult()) { 4021 NamedDecl *PrevDecl = R.getFoundDecl(); 4022 if (PrevDecl->isTemplateParameter()) { 4023 // Maybe we will complain about the shadowed template parameter. 4024 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4025 // Just pretend that we didn't see the previous declaration. 4026 PrevDecl = 0; 4027 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4028 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4029 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4030 4031 // Recover by removing the name 4032 II = 0; 4033 D.SetIdentifier(0, D.getIdentifierLoc()); 4034 D.setInvalidType(true); 4035 } 4036 } 4037 } 4038 4039 // Parameters can not be abstract class types. 4040 // For record types, this is done by the AbstractClassUsageDiagnoser once 4041 // the class has been completely parsed. 4042 if (!CurContext->isRecord() && 4043 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 4044 diag::err_abstract_type_in_decl, 4045 AbstractParamType)) 4046 D.setInvalidType(true); 4047 4048 QualType T = adjustParameterType(parmDeclType); 4049 4050 // Temporarily put parameter variables in the translation unit, not 4051 // the enclosing context. This prevents them from accidentally 4052 // looking like class members in C++. 4053 DeclContext *DC = Context.getTranslationUnitDecl(); 4054 4055 ParmVarDecl *New 4056 = ParmVarDecl::Create(Context, DC, D.getIdentifierLoc(), II, 4057 T, TInfo, StorageClass, 0); 4058 4059 if (D.isInvalidType()) 4060 New->setInvalidDecl(); 4061 4062 // Parameter declarators cannot be interface types. All ObjC objects are 4063 // passed by reference. 4064 if (T->isObjCInterfaceType()) { 4065 Diag(D.getIdentifierLoc(), 4066 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4067 New->setInvalidDecl(); 4068 } 4069 4070 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4071 if (D.getCXXScopeSpec().isSet()) { 4072 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4073 << D.getCXXScopeSpec().getRange(); 4074 New->setInvalidDecl(); 4075 } 4076 4077 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4078 // duration shall not be qualified by an address-space qualifier." 4079 // Since all parameters have automatic store duration, they can not have 4080 // an address space. 4081 if (T.getAddressSpace() != 0) { 4082 Diag(D.getIdentifierLoc(), 4083 diag::err_arg_with_address_space); 4084 New->setInvalidDecl(); 4085 } 4086 4087 4088 // Add the parameter declaration into this scope. 4089 S->AddDecl(DeclPtrTy::make(New)); 4090 if (II) 4091 IdResolver.AddDecl(New); 4092 4093 ProcessDeclAttributes(S, New, D); 4094 4095 if (New->hasAttr<BlocksAttr>()) { 4096 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4097 } 4098 return DeclPtrTy::make(New); 4099} 4100 4101void Sema::ActOnObjCCatchParam(DeclPtrTy D) { 4102 ParmVarDecl *Param = cast<ParmVarDecl>(D.getAs<Decl>()); 4103 Param->setDeclContext(CurContext); 4104} 4105 4106void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4107 SourceLocation LocAfterDecls) { 4108 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4109 "Not a function declarator!"); 4110 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4111 4112 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4113 // for a K&R function. 4114 if (!FTI.hasPrototype) { 4115 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4116 --i; 4117 if (FTI.ArgInfo[i].Param == 0) { 4118 llvm::SmallString<256> Code; 4119 llvm::raw_svector_ostream(Code) << " int " 4120 << FTI.ArgInfo[i].Ident->getName() 4121 << ";\n"; 4122 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4123 << FTI.ArgInfo[i].Ident 4124 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4125 4126 // Implicitly declare the argument as type 'int' for lack of a better 4127 // type. 4128 DeclSpec DS; 4129 const char* PrevSpec; // unused 4130 unsigned DiagID; // unused 4131 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4132 PrevSpec, DiagID); 4133 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4134 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4135 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4136 } 4137 } 4138 } 4139} 4140 4141Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4142 Declarator &D) { 4143 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4144 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4145 "Not a function declarator!"); 4146 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4147 4148 if (FTI.hasPrototype) { 4149 // FIXME: Diagnose arguments without names in C. 4150 } 4151 4152 Scope *ParentScope = FnBodyScope->getParent(); 4153 4154 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4155 MultiTemplateParamsArg(*this), 4156 /*IsFunctionDefinition=*/true); 4157 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4158} 4159 4160static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4161 // Don't warn about invalid declarations. 4162 if (FD->isInvalidDecl()) 4163 return false; 4164 4165 // Or declarations that aren't global. 4166 if (!FD->isGlobal()) 4167 return false; 4168 4169 // Don't warn about C++ member functions. 4170 if (isa<CXXMethodDecl>(FD)) 4171 return false; 4172 4173 // Don't warn about 'main'. 4174 if (FD->isMain()) 4175 return false; 4176 4177 // Don't warn about inline functions. 4178 if (FD->isInlineSpecified()) 4179 return false; 4180 4181 // Don't warn about function templates. 4182 if (FD->getDescribedFunctionTemplate()) 4183 return false; 4184 4185 // Don't warn about function template specializations. 4186 if (FD->isFunctionTemplateSpecialization()) 4187 return false; 4188 4189 bool MissingPrototype = true; 4190 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4191 Prev; Prev = Prev->getPreviousDeclaration()) { 4192 // Ignore any declarations that occur in function or method 4193 // scope, because they aren't visible from the header. 4194 if (Prev->getDeclContext()->isFunctionOrMethod()) 4195 continue; 4196 4197 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4198 break; 4199 } 4200 4201 return MissingPrototype; 4202} 4203 4204Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4205 // Clear the last template instantiation error context. 4206 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4207 4208 if (!D) 4209 return D; 4210 FunctionDecl *FD = 0; 4211 4212 if (FunctionTemplateDecl *FunTmpl 4213 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4214 FD = FunTmpl->getTemplatedDecl(); 4215 else 4216 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4217 4218 // Enter a new function scope 4219 PushFunctionScope(); 4220 4221 // See if this is a redefinition. 4222 // But don't complain if we're in GNU89 mode and the previous definition 4223 // was an extern inline function. 4224 const FunctionDecl *Definition; 4225 if (FD->getBody(Definition) && 4226 !canRedefineFunction(Definition, getLangOptions())) { 4227 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4228 Diag(Definition->getLocation(), diag::note_previous_definition); 4229 } 4230 4231 // Builtin functions cannot be defined. 4232 if (unsigned BuiltinID = FD->getBuiltinID()) { 4233 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4234 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4235 FD->setInvalidDecl(); 4236 } 4237 } 4238 4239 // The return type of a function definition must be complete 4240 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4241 QualType ResultType = FD->getResultType(); 4242 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4243 !FD->isInvalidDecl() && 4244 RequireCompleteType(FD->getLocation(), ResultType, 4245 diag::err_func_def_incomplete_result)) 4246 FD->setInvalidDecl(); 4247 4248 // GNU warning -Wmissing-prototypes: 4249 // Warn if a global function is defined without a previous 4250 // prototype declaration. This warning is issued even if the 4251 // definition itself provides a prototype. The aim is to detect 4252 // global functions that fail to be declared in header files. 4253 if (ShouldWarnAboutMissingPrototype(FD)) 4254 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4255 4256 if (FnBodyScope) 4257 PushDeclContext(FnBodyScope, FD); 4258 4259 // Check the validity of our function parameters 4260 CheckParmsForFunctionDef(FD); 4261 4262 bool ShouldCheckShadow = 4263 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4264 4265 // Introduce our parameters into the function scope 4266 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4267 ParmVarDecl *Param = FD->getParamDecl(p); 4268 Param->setOwningFunction(FD); 4269 4270 // If this has an identifier, add it to the scope stack. 4271 if (Param->getIdentifier() && FnBodyScope) { 4272 if (ShouldCheckShadow) 4273 CheckShadow(FnBodyScope, Param); 4274 4275 PushOnScopeChains(Param, FnBodyScope); 4276 } 4277 } 4278 4279 // Checking attributes of current function definition 4280 // dllimport attribute. 4281 if (FD->getAttr<DLLImportAttr>() && 4282 (!FD->getAttr<DLLExportAttr>())) { 4283 // dllimport attribute cannot be applied to definition. 4284 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4285 Diag(FD->getLocation(), 4286 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4287 << "dllimport"; 4288 FD->setInvalidDecl(); 4289 return DeclPtrTy::make(FD); 4290 } 4291 4292 // Visual C++ appears to not think this is an issue, so only issue 4293 // a warning when Microsoft extensions are disabled. 4294 if (!LangOpts.Microsoft) { 4295 // If a symbol previously declared dllimport is later defined, the 4296 // attribute is ignored in subsequent references, and a warning is 4297 // emitted. 4298 Diag(FD->getLocation(), 4299 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4300 << FD->getNameAsCString() << "dllimport"; 4301 } 4302 } 4303 return DeclPtrTy::make(FD); 4304} 4305 4306Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4307 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4308} 4309 4310Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4311 bool IsInstantiation) { 4312 Decl *dcl = D.getAs<Decl>(); 4313 Stmt *Body = BodyArg.takeAs<Stmt>(); 4314 4315 FunctionDecl *FD = 0; 4316 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4317 if (FunTmpl) 4318 FD = FunTmpl->getTemplatedDecl(); 4319 else 4320 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4321 4322 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4323 4324 if (FD) { 4325 FD->setBody(Body); 4326 if (FD->isMain()) { 4327 // C and C++ allow for main to automagically return 0. 4328 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4329 FD->setHasImplicitReturnZero(true); 4330 WP.disableCheckFallThrough(); 4331 } 4332 4333 if (!FD->isInvalidDecl()) 4334 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4335 4336 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4337 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4338 4339 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4340 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4341 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4342 MD->setBody(Body); 4343 MD->setEndLoc(Body->getLocEnd()); 4344 if (!MD->isInvalidDecl()) 4345 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4346 } else { 4347 Body->Destroy(Context); 4348 return DeclPtrTy(); 4349 } 4350 4351 // Verify and clean out per-function state. 4352 4353 // Check goto/label use. 4354 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4355 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4356 LabelStmt *L = I->second; 4357 4358 // Verify that we have no forward references left. If so, there was a goto 4359 // or address of a label taken, but no definition of it. Label fwd 4360 // definitions are indicated with a null substmt. 4361 if (L->getSubStmt() != 0) 4362 continue; 4363 4364 // Emit error. 4365 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4366 4367 // At this point, we have gotos that use the bogus label. Stitch it into 4368 // the function body so that they aren't leaked and that the AST is well 4369 // formed. 4370 if (Body == 0) { 4371 // The whole function wasn't parsed correctly, just delete this. 4372 L->Destroy(Context); 4373 continue; 4374 } 4375 4376 // Otherwise, the body is valid: we want to stitch the label decl into the 4377 // function somewhere so that it is properly owned and so that the goto 4378 // has a valid target. Do this by creating a new compound stmt with the 4379 // label in it. 4380 4381 // Give the label a sub-statement. 4382 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4383 4384 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4385 cast<CXXTryStmt>(Body)->getTryBlock() : 4386 cast<CompoundStmt>(Body); 4387 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4388 Compound->body_end()); 4389 Elements.push_back(L); 4390 Compound->setStmts(Context, Elements.data(), Elements.size()); 4391 } 4392 4393 if (Body) { 4394 // C++ constructors that have function-try-blocks can't have return 4395 // statements in the handlers of that block. (C++ [except.handle]p14) 4396 // Verify this. 4397 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4398 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4399 4400 // Verify that that gotos and switch cases don't jump into scopes illegally. 4401 // Verify that that gotos and switch cases don't jump into scopes illegally. 4402 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 4403 DiagnoseInvalidJumps(Body); 4404 4405 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4406 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4407 Destructor->getParent()); 4408 4409 // If any errors have occurred, clear out any temporaries that may have 4410 // been leftover. This ensures that these temporaries won't be picked up for 4411 // deletion in some later function. 4412 if (PP.getDiagnostics().hasErrorOccurred()) 4413 ExprTemporaries.clear(); 4414 else if (!isa<FunctionTemplateDecl>(dcl)) { 4415 // Since the body is valid, issue any analysis-based warnings that are 4416 // enabled. 4417 QualType ResultType; 4418 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4419 ResultType = FD->getResultType(); 4420 } 4421 else { 4422 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4423 ResultType = MD->getResultType(); 4424 } 4425 AnalysisWarnings.IssueWarnings(WP, dcl); 4426 } 4427 4428 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4429 } 4430 4431 if (!IsInstantiation) 4432 PopDeclContext(); 4433 4434 PopFunctionOrBlockScope(); 4435 4436 // If any errors have occurred, clear out any temporaries that may have 4437 // been leftover. This ensures that these temporaries won't be picked up for 4438 // deletion in some later function. 4439 if (getDiagnostics().hasErrorOccurred()) 4440 ExprTemporaries.clear(); 4441 4442 return D; 4443} 4444 4445/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4446/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4447NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4448 IdentifierInfo &II, Scope *S) { 4449 // Before we produce a declaration for an implicitly defined 4450 // function, see whether there was a locally-scoped declaration of 4451 // this name as a function or variable. If so, use that 4452 // (non-visible) declaration, and complain about it. 4453 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4454 = LocallyScopedExternalDecls.find(&II); 4455 if (Pos != LocallyScopedExternalDecls.end()) { 4456 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4457 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4458 return Pos->second; 4459 } 4460 4461 // Extension in C99. Legal in C90, but warn about it. 4462 if (II.getName().startswith("__builtin_")) 4463 Diag(Loc, diag::warn_builtin_unknown) << &II; 4464 else if (getLangOptions().C99) 4465 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4466 else 4467 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4468 4469 // Set a Declarator for the implicit definition: int foo(); 4470 const char *Dummy; 4471 DeclSpec DS; 4472 unsigned DiagID; 4473 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4474 Error = Error; // Silence warning. 4475 assert(!Error && "Error setting up implicit decl!"); 4476 Declarator D(DS, Declarator::BlockContext); 4477 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4478 0, 0, false, SourceLocation(), 4479 false, 0,0,0, Loc, Loc, D), 4480 SourceLocation()); 4481 D.SetIdentifier(&II, Loc); 4482 4483 // Insert this function into translation-unit scope. 4484 4485 DeclContext *PrevDC = CurContext; 4486 CurContext = Context.getTranslationUnitDecl(); 4487 4488 FunctionDecl *FD = 4489 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4490 FD->setImplicit(); 4491 4492 CurContext = PrevDC; 4493 4494 AddKnownFunctionAttributes(FD); 4495 4496 return FD; 4497} 4498 4499/// \brief Adds any function attributes that we know a priori based on 4500/// the declaration of this function. 4501/// 4502/// These attributes can apply both to implicitly-declared builtins 4503/// (like __builtin___printf_chk) or to library-declared functions 4504/// like NSLog or printf. 4505void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4506 if (FD->isInvalidDecl()) 4507 return; 4508 4509 // If this is a built-in function, map its builtin attributes to 4510 // actual attributes. 4511 if (unsigned BuiltinID = FD->getBuiltinID()) { 4512 // Handle printf-formatting attributes. 4513 unsigned FormatIdx; 4514 bool HasVAListArg; 4515 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4516 if (!FD->getAttr<FormatAttr>()) 4517 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4518 HasVAListArg ? 0 : FormatIdx+2)); 4519 } 4520 4521 // Mark const if we don't care about errno and that is the only 4522 // thing preventing the function from being const. This allows 4523 // IRgen to use LLVM intrinsics for such functions. 4524 if (!getLangOptions().MathErrno && 4525 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4526 if (!FD->getAttr<ConstAttr>()) 4527 FD->addAttr(::new (Context) ConstAttr()); 4528 } 4529 4530 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4531 FD->setType(Context.getNoReturnType(FD->getType())); 4532 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4533 FD->addAttr(::new (Context) NoThrowAttr()); 4534 if (Context.BuiltinInfo.isConst(BuiltinID)) 4535 FD->addAttr(::new (Context) ConstAttr()); 4536 } 4537 4538 IdentifierInfo *Name = FD->getIdentifier(); 4539 if (!Name) 4540 return; 4541 if ((!getLangOptions().CPlusPlus && 4542 FD->getDeclContext()->isTranslationUnit()) || 4543 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4544 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4545 LinkageSpecDecl::lang_c)) { 4546 // Okay: this could be a libc/libm/Objective-C function we know 4547 // about. 4548 } else 4549 return; 4550 4551 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4552 // FIXME: NSLog and NSLogv should be target specific 4553 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4554 // FIXME: We known better than our headers. 4555 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4556 } else 4557 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4558 Name->isStr("NSLogv") ? 0 : 2)); 4559 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4560 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4561 // target-specific builtins, perhaps? 4562 if (!FD->getAttr<FormatAttr>()) 4563 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4564 Name->isStr("vasprintf") ? 0 : 3)); 4565 } 4566} 4567 4568TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4569 TypeSourceInfo *TInfo) { 4570 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4571 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4572 4573 if (!TInfo) { 4574 assert(D.isInvalidType() && "no declarator info for valid type"); 4575 TInfo = Context.getTrivialTypeSourceInfo(T); 4576 } 4577 4578 // Scope manipulation handled by caller. 4579 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4580 D.getIdentifierLoc(), 4581 D.getIdentifier(), 4582 TInfo); 4583 4584 if (const TagType *TT = T->getAs<TagType>()) { 4585 TagDecl *TD = TT->getDecl(); 4586 4587 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4588 // keep track of the TypedefDecl. 4589 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4590 TD->setTypedefForAnonDecl(NewTD); 4591 } 4592 4593 if (D.isInvalidType()) 4594 NewTD->setInvalidDecl(); 4595 return NewTD; 4596} 4597 4598 4599/// \brief Determine whether a tag with a given kind is acceptable 4600/// as a redeclaration of the given tag declaration. 4601/// 4602/// \returns true if the new tag kind is acceptable, false otherwise. 4603bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4604 TagDecl::TagKind NewTag, 4605 SourceLocation NewTagLoc, 4606 const IdentifierInfo &Name) { 4607 // C++ [dcl.type.elab]p3: 4608 // The class-key or enum keyword present in the 4609 // elaborated-type-specifier shall agree in kind with the 4610 // declaration to which the name in theelaborated-type-specifier 4611 // refers. This rule also applies to the form of 4612 // elaborated-type-specifier that declares a class-name or 4613 // friend class since it can be construed as referring to the 4614 // definition of the class. Thus, in any 4615 // elaborated-type-specifier, the enum keyword shall be used to 4616 // refer to an enumeration (7.2), the union class-keyshall be 4617 // used to refer to a union (clause 9), and either the class or 4618 // struct class-key shall be used to refer to a class (clause 9) 4619 // declared using the class or struct class-key. 4620 TagDecl::TagKind OldTag = Previous->getTagKind(); 4621 if (OldTag == NewTag) 4622 return true; 4623 4624 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4625 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4626 // Warn about the struct/class tag mismatch. 4627 bool isTemplate = false; 4628 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4629 isTemplate = Record->getDescribedClassTemplate(); 4630 4631 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4632 << (NewTag == TagDecl::TK_class) 4633 << isTemplate << &Name 4634 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4635 OldTag == TagDecl::TK_class? "class" : "struct"); 4636 Diag(Previous->getLocation(), diag::note_previous_use); 4637 return true; 4638 } 4639 return false; 4640} 4641 4642/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4643/// former case, Name will be non-null. In the later case, Name will be null. 4644/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4645/// reference/declaration/definition of a tag. 4646Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4647 SourceLocation KWLoc, const CXXScopeSpec &SS, 4648 IdentifierInfo *Name, SourceLocation NameLoc, 4649 AttributeList *Attr, AccessSpecifier AS, 4650 MultiTemplateParamsArg TemplateParameterLists, 4651 bool &OwnedDecl, bool &IsDependent) { 4652 // If this is not a definition, it must have a name. 4653 assert((Name != 0 || TUK == TUK_Definition) && 4654 "Nameless record must be a definition!"); 4655 4656 OwnedDecl = false; 4657 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4658 4659 // FIXME: Check explicit specializations more carefully. 4660 bool isExplicitSpecialization = false; 4661 if (TUK != TUK_Reference) { 4662 if (TemplateParameterList *TemplateParams 4663 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4664 (TemplateParameterList**)TemplateParameterLists.get(), 4665 TemplateParameterLists.size(), 4666 isExplicitSpecialization)) { 4667 if (TemplateParams->size() > 0) { 4668 // This is a declaration or definition of a class template (which may 4669 // be a member of another template). 4670 OwnedDecl = false; 4671 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4672 SS, Name, NameLoc, Attr, 4673 TemplateParams, 4674 AS); 4675 TemplateParameterLists.release(); 4676 return Result.get(); 4677 } else { 4678 // The "template<>" header is extraneous. 4679 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4680 << ElaboratedType::getNameForTagKind(Kind) << Name; 4681 isExplicitSpecialization = true; 4682 } 4683 } 4684 4685 TemplateParameterLists.release(); 4686 } 4687 4688 DeclContext *SearchDC = CurContext; 4689 DeclContext *DC = CurContext; 4690 bool isStdBadAlloc = false; 4691 bool Invalid = false; 4692 4693 RedeclarationKind Redecl = ForRedeclaration; 4694 if (TUK == TUK_Friend || TUK == TUK_Reference) 4695 Redecl = NotForRedeclaration; 4696 4697 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4698 4699 if (Name && SS.isNotEmpty()) { 4700 // We have a nested-name tag ('struct foo::bar'). 4701 4702 // Check for invalid 'foo::'. 4703 if (SS.isInvalid()) { 4704 Name = 0; 4705 goto CreateNewDecl; 4706 } 4707 4708 // If this is a friend or a reference to a class in a dependent 4709 // context, don't try to make a decl for it. 4710 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4711 DC = computeDeclContext(SS, false); 4712 if (!DC) { 4713 IsDependent = true; 4714 return DeclPtrTy(); 4715 } 4716 } 4717 4718 if (RequireCompleteDeclContext(SS)) 4719 return DeclPtrTy::make((Decl *)0); 4720 4721 DC = computeDeclContext(SS, true); 4722 SearchDC = DC; 4723 // Look-up name inside 'foo::'. 4724 LookupQualifiedName(Previous, DC); 4725 4726 if (Previous.isAmbiguous()) 4727 return DeclPtrTy(); 4728 4729 if (Previous.empty()) { 4730 // Name lookup did not find anything. However, if the 4731 // nested-name-specifier refers to the current instantiation, 4732 // and that current instantiation has any dependent base 4733 // classes, we might find something at instantiation time: treat 4734 // this as a dependent elaborated-type-specifier. 4735 if (Previous.wasNotFoundInCurrentInstantiation()) { 4736 IsDependent = true; 4737 return DeclPtrTy(); 4738 } 4739 4740 // A tag 'foo::bar' must already exist. 4741 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4742 Name = 0; 4743 Invalid = true; 4744 goto CreateNewDecl; 4745 } 4746 } else if (Name) { 4747 // If this is a named struct, check to see if there was a previous forward 4748 // declaration or definition. 4749 // FIXME: We're looking into outer scopes here, even when we 4750 // shouldn't be. Doing so can result in ambiguities that we 4751 // shouldn't be diagnosing. 4752 LookupName(Previous, S); 4753 4754 // Note: there used to be some attempt at recovery here. 4755 if (Previous.isAmbiguous()) 4756 return DeclPtrTy(); 4757 4758 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4759 // FIXME: This makes sure that we ignore the contexts associated 4760 // with C structs, unions, and enums when looking for a matching 4761 // tag declaration or definition. See the similar lookup tweak 4762 // in Sema::LookupName; is there a better way to deal with this? 4763 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4764 SearchDC = SearchDC->getParent(); 4765 } 4766 } 4767 4768 if (Previous.isSingleResult() && 4769 Previous.getFoundDecl()->isTemplateParameter()) { 4770 // Maybe we will complain about the shadowed template parameter. 4771 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4772 // Just pretend that we didn't see the previous declaration. 4773 Previous.clear(); 4774 } 4775 4776 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4777 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4778 // This is a declaration of or a reference to "std::bad_alloc". 4779 isStdBadAlloc = true; 4780 4781 if (Previous.empty() && StdBadAlloc) { 4782 // std::bad_alloc has been implicitly declared (but made invisible to 4783 // name lookup). Fill in this implicit declaration as the previous 4784 // declaration, so that the declarations get chained appropriately. 4785 Previous.addDecl(StdBadAlloc); 4786 } 4787 } 4788 4789 // If we didn't find a previous declaration, and this is a reference 4790 // (or friend reference), move to the correct scope. In C++, we 4791 // also need to do a redeclaration lookup there, just in case 4792 // there's a shadow friend decl. 4793 if (Name && Previous.empty() && 4794 (TUK == TUK_Reference || TUK == TUK_Friend)) { 4795 if (Invalid) goto CreateNewDecl; 4796 assert(SS.isEmpty()); 4797 4798 if (TUK == TUK_Reference) { 4799 // C++ [basic.scope.pdecl]p5: 4800 // -- for an elaborated-type-specifier of the form 4801 // 4802 // class-key identifier 4803 // 4804 // if the elaborated-type-specifier is used in the 4805 // decl-specifier-seq or parameter-declaration-clause of a 4806 // function defined in namespace scope, the identifier is 4807 // declared as a class-name in the namespace that contains 4808 // the declaration; otherwise, except as a friend 4809 // declaration, the identifier is declared in the smallest 4810 // non-class, non-function-prototype scope that contains the 4811 // declaration. 4812 // 4813 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4814 // C structs and unions. 4815 // 4816 // It is an error in C++ to declare (rather than define) an enum 4817 // type, including via an elaborated type specifier. We'll 4818 // diagnose that later; for now, declare the enum in the same 4819 // scope as we would have picked for any other tag type. 4820 // 4821 // GNU C also supports this behavior as part of its incomplete 4822 // enum types extension, while GNU C++ does not. 4823 // 4824 // Find the context where we'll be declaring the tag. 4825 // FIXME: We would like to maintain the current DeclContext as the 4826 // lexical context, 4827 while (SearchDC->isRecord()) 4828 SearchDC = SearchDC->getParent(); 4829 4830 // Find the scope where we'll be declaring the tag. 4831 while (S->isClassScope() || 4832 (getLangOptions().CPlusPlus && 4833 S->isFunctionPrototypeScope()) || 4834 ((S->getFlags() & Scope::DeclScope) == 0) || 4835 (S->getEntity() && 4836 ((DeclContext *)S->getEntity())->isTransparentContext())) 4837 S = S->getParent(); 4838 } else { 4839 assert(TUK == TUK_Friend); 4840 // C++ [namespace.memdef]p3: 4841 // If a friend declaration in a non-local class first declares a 4842 // class or function, the friend class or function is a member of 4843 // the innermost enclosing namespace. 4844 SearchDC = SearchDC->getEnclosingNamespaceContext(); 4845 4846 // Look up through our scopes until we find one with an entity which 4847 // matches our declaration context. 4848 while (S->getEntity() && 4849 ((DeclContext *)S->getEntity())->getPrimaryContext() != SearchDC) { 4850 S = S->getParent(); 4851 assert(S && "No enclosing scope matching the enclosing namespace."); 4852 } 4853 } 4854 4855 // In C++, look for a shadow friend decl. 4856 if (getLangOptions().CPlusPlus) { 4857 Previous.setRedeclarationKind(ForRedeclaration); 4858 LookupQualifiedName(Previous, SearchDC); 4859 } 4860 } 4861 4862 if (!Previous.empty()) { 4863 assert(Previous.isSingleResult()); 4864 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4865 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4866 // If this is a use of a previous tag, or if the tag is already declared 4867 // in the same scope (so that the definition/declaration completes or 4868 // rementions the tag), reuse the decl. 4869 if (TUK == TUK_Reference || TUK == TUK_Friend || 4870 isDeclInScope(PrevDecl, SearchDC, S)) { 4871 // Make sure that this wasn't declared as an enum and now used as a 4872 // struct or something similar. 4873 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4874 bool SafeToContinue 4875 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4876 Kind != TagDecl::TK_enum); 4877 if (SafeToContinue) 4878 Diag(KWLoc, diag::err_use_with_wrong_tag) 4879 << Name 4880 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4881 PrevTagDecl->getKindName()); 4882 else 4883 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4884 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4885 4886 if (SafeToContinue) 4887 Kind = PrevTagDecl->getTagKind(); 4888 else { 4889 // Recover by making this an anonymous redefinition. 4890 Name = 0; 4891 Previous.clear(); 4892 Invalid = true; 4893 } 4894 } 4895 4896 if (!Invalid) { 4897 // If this is a use, just return the declaration we found. 4898 4899 // FIXME: In the future, return a variant or some other clue 4900 // for the consumer of this Decl to know it doesn't own it. 4901 // For our current ASTs this shouldn't be a problem, but will 4902 // need to be changed with DeclGroups. 4903 if (TUK == TUK_Reference || TUK == TUK_Friend) 4904 return DeclPtrTy::make(PrevTagDecl); 4905 4906 // Diagnose attempts to redefine a tag. 4907 if (TUK == TUK_Definition) { 4908 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 4909 // If we're defining a specialization and the previous definition 4910 // is from an implicit instantiation, don't emit an error 4911 // here; we'll catch this in the general case below. 4912 if (!isExplicitSpecialization || 4913 !isa<CXXRecordDecl>(Def) || 4914 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4915 == TSK_ExplicitSpecialization) { 4916 Diag(NameLoc, diag::err_redefinition) << Name; 4917 Diag(Def->getLocation(), diag::note_previous_definition); 4918 // If this is a redefinition, recover by making this 4919 // struct be anonymous, which will make any later 4920 // references get the previous definition. 4921 Name = 0; 4922 Previous.clear(); 4923 Invalid = true; 4924 } 4925 } else { 4926 // If the type is currently being defined, complain 4927 // about a nested redefinition. 4928 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4929 if (Tag->isBeingDefined()) { 4930 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4931 Diag(PrevTagDecl->getLocation(), 4932 diag::note_previous_definition); 4933 Name = 0; 4934 Previous.clear(); 4935 Invalid = true; 4936 } 4937 } 4938 4939 // Okay, this is definition of a previously declared or referenced 4940 // tag PrevDecl. We're going to create a new Decl for it. 4941 } 4942 } 4943 // If we get here we have (another) forward declaration or we 4944 // have a definition. Just create a new decl. 4945 4946 } else { 4947 // If we get here, this is a definition of a new tag type in a nested 4948 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4949 // new decl/type. We set PrevDecl to NULL so that the entities 4950 // have distinct types. 4951 Previous.clear(); 4952 } 4953 // If we get here, we're going to create a new Decl. If PrevDecl 4954 // is non-NULL, it's a definition of the tag declared by 4955 // PrevDecl. If it's NULL, we have a new definition. 4956 } else { 4957 // PrevDecl is a namespace, template, or anything else 4958 // that lives in the IDNS_Tag identifier namespace. 4959 if (TUK == TUK_Reference || TUK == TUK_Friend || 4960 isDeclInScope(PrevDecl, SearchDC, S)) { 4961 // The tag name clashes with a namespace name, issue an error and 4962 // recover by making this tag be anonymous. 4963 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4964 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4965 Name = 0; 4966 Previous.clear(); 4967 Invalid = true; 4968 } else { 4969 // The existing declaration isn't relevant to us; we're in a 4970 // new scope, so clear out the previous declaration. 4971 Previous.clear(); 4972 } 4973 } 4974 } 4975 4976CreateNewDecl: 4977 4978 TagDecl *PrevDecl = 0; 4979 if (Previous.isSingleResult()) 4980 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4981 4982 // If there is an identifier, use the location of the identifier as the 4983 // location of the decl, otherwise use the location of the struct/union 4984 // keyword. 4985 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4986 4987 // Otherwise, create a new declaration. If there is a previous 4988 // declaration of the same entity, the two will be linked via 4989 // PrevDecl. 4990 TagDecl *New; 4991 4992 if (Kind == TagDecl::TK_enum) { 4993 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4994 // enum X { A, B, C } D; D should chain to X. 4995 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4996 cast_or_null<EnumDecl>(PrevDecl)); 4997 // If this is an undefined enum, warn. 4998 if (TUK != TUK_Definition && !Invalid) { 4999 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5000 : diag::ext_forward_ref_enum; 5001 Diag(Loc, DK); 5002 } 5003 } else { 5004 // struct/union/class 5005 5006 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5007 // struct X { int A; } D; D should chain to X. 5008 if (getLangOptions().CPlusPlus) { 5009 // FIXME: Look for a way to use RecordDecl for simple structs. 5010 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5011 cast_or_null<CXXRecordDecl>(PrevDecl)); 5012 5013 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5014 StdBadAlloc = cast<CXXRecordDecl>(New); 5015 } else 5016 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5017 cast_or_null<RecordDecl>(PrevDecl)); 5018 } 5019 5020 // Maybe add qualifier info. 5021 if (SS.isNotEmpty()) { 5022 NestedNameSpecifier *NNS 5023 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5024 New->setQualifierInfo(NNS, SS.getRange()); 5025 } 5026 5027 if (Kind != TagDecl::TK_enum) { 5028 // Handle #pragma pack: if the #pragma pack stack has non-default 5029 // alignment, make up a packed attribute for this decl. These 5030 // attributes are checked when the ASTContext lays out the 5031 // structure. 5032 // 5033 // It is important for implementing the correct semantics that this 5034 // happen here (in act on tag decl). The #pragma pack stack is 5035 // maintained as a result of parser callbacks which can occur at 5036 // many points during the parsing of a struct declaration (because 5037 // the #pragma tokens are effectively skipped over during the 5038 // parsing of the struct). 5039 if (unsigned Alignment = getPragmaPackAlignment()) 5040 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 5041 } 5042 5043 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 5044 // C++ [dcl.typedef]p3: 5045 // [...] Similarly, in a given scope, a class or enumeration 5046 // shall not be declared with the same name as a typedef-name 5047 // that is declared in that scope and refers to a type other 5048 // than the class or enumeration itself. 5049 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 5050 ForRedeclaration); 5051 LookupName(Lookup, S); 5052 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 5053 NamedDecl *PrevTypedefNamed = PrevTypedef; 5054 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 5055 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 5056 Context.getCanonicalType(Context.getTypeDeclType(New))) { 5057 Diag(Loc, diag::err_tag_definition_of_typedef) 5058 << Context.getTypeDeclType(New) 5059 << PrevTypedef->getUnderlyingType(); 5060 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 5061 Invalid = true; 5062 } 5063 } 5064 5065 // If this is a specialization of a member class (of a class template), 5066 // check the specialization. 5067 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5068 Invalid = true; 5069 5070 if (Invalid) 5071 New->setInvalidDecl(); 5072 5073 if (Attr) 5074 ProcessDeclAttributeList(S, New, Attr); 5075 5076 // If we're declaring or defining a tag in function prototype scope 5077 // in C, note that this type can only be used within the function. 5078 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5079 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5080 5081 // Set the lexical context. If the tag has a C++ scope specifier, the 5082 // lexical context will be different from the semantic context. 5083 New->setLexicalDeclContext(CurContext); 5084 5085 // Mark this as a friend decl if applicable. 5086 if (TUK == TUK_Friend) 5087 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5088 5089 // Set the access specifier. 5090 if (!Invalid && SearchDC->isRecord()) 5091 SetMemberAccessSpecifier(New, PrevDecl, AS); 5092 5093 if (TUK == TUK_Definition) 5094 New->startDefinition(); 5095 5096 // If this has an identifier, add it to the scope stack. 5097 if (TUK == TUK_Friend) { 5098 // We might be replacing an existing declaration in the lookup tables; 5099 // if so, borrow its access specifier. 5100 if (PrevDecl) 5101 New->setAccess(PrevDecl->getAccess()); 5102 5103 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5104 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5105 if (Name) // can be null along some error paths 5106 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5107 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5108 } else if (Name) { 5109 S = getNonFieldDeclScope(S); 5110 PushOnScopeChains(New, S); 5111 } else { 5112 CurContext->addDecl(New); 5113 } 5114 5115 // If this is the C FILE type, notify the AST context. 5116 if (IdentifierInfo *II = New->getIdentifier()) 5117 if (!New->isInvalidDecl() && 5118 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5119 II->isStr("FILE")) 5120 Context.setFILEDecl(New); 5121 5122 OwnedDecl = true; 5123 return DeclPtrTy::make(New); 5124} 5125 5126void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5127 AdjustDeclIfTemplate(TagD); 5128 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5129 5130 // Enter the tag context. 5131 PushDeclContext(S, Tag); 5132} 5133 5134void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5135 SourceLocation LBraceLoc) { 5136 AdjustDeclIfTemplate(TagD); 5137 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5138 5139 FieldCollector->StartClass(); 5140 5141 if (!Record->getIdentifier()) 5142 return; 5143 5144 // C++ [class]p2: 5145 // [...] The class-name is also inserted into the scope of the 5146 // class itself; this is known as the injected-class-name. For 5147 // purposes of access checking, the injected-class-name is treated 5148 // as if it were a public member name. 5149 CXXRecordDecl *InjectedClassName 5150 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5151 CurContext, Record->getLocation(), 5152 Record->getIdentifier(), 5153 Record->getTagKeywordLoc(), 5154 Record); 5155 InjectedClassName->setImplicit(); 5156 InjectedClassName->setAccess(AS_public); 5157 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5158 InjectedClassName->setDescribedClassTemplate(Template); 5159 PushOnScopeChains(InjectedClassName, S); 5160 assert(InjectedClassName->isInjectedClassName() && 5161 "Broken injected-class-name"); 5162} 5163 5164// Traverses the class and any nested classes, making a note of any 5165// dynamic classes that have no key function so that we can mark all of 5166// their virtual member functions as "used" at the end of the translation 5167// unit. This ensures that all functions needed by the vtable will get 5168// instantiated/synthesized. 5169static void 5170RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 5171 SourceLocation Loc) { 5172 // We don't look at dependent or undefined classes. 5173 if (Record->isDependentContext() || !Record->isDefinition()) 5174 return; 5175 5176 if (Record->isDynamicClass()) { 5177 const CXXMethodDecl *KeyFunction = S.Context.getKeyFunction(Record); 5178 5179 if (!KeyFunction) 5180 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, 5181 Loc)); 5182 5183 if ((!KeyFunction || (KeyFunction->getBody() && KeyFunction->isInlined())) 5184 && Record->getLinkage() == ExternalLinkage) 5185 S.Diag(Record->getLocation(), diag::warn_weak_vtable) << Record; 5186 } 5187 for (DeclContext::decl_iterator D = Record->decls_begin(), 5188 DEnd = Record->decls_end(); 5189 D != DEnd; ++D) { 5190 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 5191 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 5192 } 5193} 5194 5195void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5196 SourceLocation RBraceLoc) { 5197 AdjustDeclIfTemplate(TagD); 5198 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5199 Tag->setRBraceLoc(RBraceLoc); 5200 5201 if (isa<CXXRecordDecl>(Tag)) 5202 FieldCollector->FinishClass(); 5203 5204 // Exit this scope of this tag's definition. 5205 PopDeclContext(); 5206 5207 if (isa<CXXRecordDecl>(Tag) && !Tag->getLexicalDeclContext()->isRecord()) 5208 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 5209 RBraceLoc); 5210 5211 // Notify the consumer that we've defined a tag. 5212 Consumer.HandleTagDeclDefinition(Tag); 5213} 5214 5215void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5216 AdjustDeclIfTemplate(TagD); 5217 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5218 Tag->setInvalidDecl(); 5219 5220 // We're undoing ActOnTagStartDefinition here, not 5221 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5222 // the FieldCollector. 5223 5224 PopDeclContext(); 5225} 5226 5227// Note that FieldName may be null for anonymous bitfields. 5228bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5229 QualType FieldTy, const Expr *BitWidth, 5230 bool *ZeroWidth) { 5231 // Default to true; that shouldn't confuse checks for emptiness 5232 if (ZeroWidth) 5233 *ZeroWidth = true; 5234 5235 // C99 6.7.2.1p4 - verify the field type. 5236 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5237 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5238 // Handle incomplete types with specific error. 5239 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5240 return true; 5241 if (FieldName) 5242 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5243 << FieldName << FieldTy << BitWidth->getSourceRange(); 5244 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5245 << FieldTy << BitWidth->getSourceRange(); 5246 } 5247 5248 // If the bit-width is type- or value-dependent, don't try to check 5249 // it now. 5250 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5251 return false; 5252 5253 llvm::APSInt Value; 5254 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5255 return true; 5256 5257 if (Value != 0 && ZeroWidth) 5258 *ZeroWidth = false; 5259 5260 // Zero-width bitfield is ok for anonymous field. 5261 if (Value == 0 && FieldName) 5262 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5263 5264 if (Value.isSigned() && Value.isNegative()) { 5265 if (FieldName) 5266 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5267 << FieldName << Value.toString(10); 5268 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5269 << Value.toString(10); 5270 } 5271 5272 if (!FieldTy->isDependentType()) { 5273 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5274 if (Value.getZExtValue() > TypeSize) { 5275 if (FieldName) 5276 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5277 << FieldName << (unsigned)TypeSize; 5278 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5279 << (unsigned)TypeSize; 5280 } 5281 } 5282 5283 return false; 5284} 5285 5286/// ActOnField - Each field of a struct/union/class is passed into this in order 5287/// to create a FieldDecl object for it. 5288Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5289 SourceLocation DeclStart, 5290 Declarator &D, ExprTy *BitfieldWidth) { 5291 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5292 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5293 AS_public); 5294 return DeclPtrTy::make(Res); 5295} 5296 5297/// HandleField - Analyze a field of a C struct or a C++ data member. 5298/// 5299FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5300 SourceLocation DeclStart, 5301 Declarator &D, Expr *BitWidth, 5302 AccessSpecifier AS) { 5303 IdentifierInfo *II = D.getIdentifier(); 5304 SourceLocation Loc = DeclStart; 5305 if (II) Loc = D.getIdentifierLoc(); 5306 5307 TypeSourceInfo *TInfo = 0; 5308 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5309 if (getLangOptions().CPlusPlus) 5310 CheckExtraCXXDefaultArguments(D); 5311 5312 DiagnoseFunctionSpecifiers(D); 5313 5314 if (D.getDeclSpec().isThreadSpecified()) 5315 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5316 5317 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5318 ForRedeclaration); 5319 5320 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5321 // Maybe we will complain about the shadowed template parameter. 5322 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5323 // Just pretend that we didn't see the previous declaration. 5324 PrevDecl = 0; 5325 } 5326 5327 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5328 PrevDecl = 0; 5329 5330 bool Mutable 5331 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5332 SourceLocation TSSL = D.getSourceRange().getBegin(); 5333 FieldDecl *NewFD 5334 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5335 AS, PrevDecl, &D); 5336 5337 if (NewFD->isInvalidDecl()) 5338 Record->setInvalidDecl(); 5339 5340 if (NewFD->isInvalidDecl() && PrevDecl) { 5341 // Don't introduce NewFD into scope; there's already something 5342 // with the same name in the same scope. 5343 } else if (II) { 5344 PushOnScopeChains(NewFD, S); 5345 } else 5346 Record->addDecl(NewFD); 5347 5348 return NewFD; 5349} 5350 5351/// \brief Build a new FieldDecl and check its well-formedness. 5352/// 5353/// This routine builds a new FieldDecl given the fields name, type, 5354/// record, etc. \p PrevDecl should refer to any previous declaration 5355/// with the same name and in the same scope as the field to be 5356/// created. 5357/// 5358/// \returns a new FieldDecl. 5359/// 5360/// \todo The Declarator argument is a hack. It will be removed once 5361FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5362 TypeSourceInfo *TInfo, 5363 RecordDecl *Record, SourceLocation Loc, 5364 bool Mutable, Expr *BitWidth, 5365 SourceLocation TSSL, 5366 AccessSpecifier AS, NamedDecl *PrevDecl, 5367 Declarator *D) { 5368 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5369 bool InvalidDecl = false; 5370 if (D) InvalidDecl = D->isInvalidType(); 5371 5372 // If we receive a broken type, recover by assuming 'int' and 5373 // marking this declaration as invalid. 5374 if (T.isNull()) { 5375 InvalidDecl = true; 5376 T = Context.IntTy; 5377 } 5378 5379 QualType EltTy = Context.getBaseElementType(T); 5380 if (!EltTy->isDependentType() && 5381 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5382 InvalidDecl = true; 5383 5384 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5385 // than a variably modified type. 5386 if (!InvalidDecl && T->isVariablyModifiedType()) { 5387 bool SizeIsNegative; 5388 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5389 SizeIsNegative); 5390 if (!FixedTy.isNull()) { 5391 Diag(Loc, diag::warn_illegal_constant_array_size); 5392 T = FixedTy; 5393 } else { 5394 if (SizeIsNegative) 5395 Diag(Loc, diag::err_typecheck_negative_array_size); 5396 else 5397 Diag(Loc, diag::err_typecheck_field_variable_size); 5398 InvalidDecl = true; 5399 } 5400 } 5401 5402 // Fields can not have abstract class types 5403 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5404 diag::err_abstract_type_in_decl, 5405 AbstractFieldType)) 5406 InvalidDecl = true; 5407 5408 bool ZeroWidth = false; 5409 // If this is declared as a bit-field, check the bit-field. 5410 if (!InvalidDecl && BitWidth && 5411 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5412 InvalidDecl = true; 5413 DeleteExpr(BitWidth); 5414 BitWidth = 0; 5415 ZeroWidth = false; 5416 } 5417 5418 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5419 BitWidth, Mutable); 5420 if (InvalidDecl) 5421 NewFD->setInvalidDecl(); 5422 5423 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5424 Diag(Loc, diag::err_duplicate_member) << II; 5425 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5426 NewFD->setInvalidDecl(); 5427 } 5428 5429 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5430 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5431 5432 if (!T->isPODType()) 5433 CXXRecord->setPOD(false); 5434 if (!ZeroWidth) 5435 CXXRecord->setEmpty(false); 5436 5437 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5438 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5439 5440 if (!RDecl->hasTrivialConstructor()) 5441 CXXRecord->setHasTrivialConstructor(false); 5442 if (!RDecl->hasTrivialCopyConstructor()) 5443 CXXRecord->setHasTrivialCopyConstructor(false); 5444 if (!RDecl->hasTrivialCopyAssignment()) 5445 CXXRecord->setHasTrivialCopyAssignment(false); 5446 if (!RDecl->hasTrivialDestructor()) 5447 CXXRecord->setHasTrivialDestructor(false); 5448 5449 // C++ 9.5p1: An object of a class with a non-trivial 5450 // constructor, a non-trivial copy constructor, a non-trivial 5451 // destructor, or a non-trivial copy assignment operator 5452 // cannot be a member of a union, nor can an array of such 5453 // objects. 5454 // TODO: C++0x alters this restriction significantly. 5455 if (Record->isUnion()) { 5456 // We check for copy constructors before constructors 5457 // because otherwise we'll never get complaints about 5458 // copy constructors. 5459 5460 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5461 5462 CXXSpecialMember member; 5463 if (!RDecl->hasTrivialCopyConstructor()) 5464 member = CXXCopyConstructor; 5465 else if (!RDecl->hasTrivialConstructor()) 5466 member = CXXDefaultConstructor; 5467 else if (!RDecl->hasTrivialCopyAssignment()) 5468 member = CXXCopyAssignment; 5469 else if (!RDecl->hasTrivialDestructor()) 5470 member = CXXDestructor; 5471 else 5472 member = invalid; 5473 5474 if (member != invalid) { 5475 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5476 DiagnoseNontrivial(RT, member); 5477 NewFD->setInvalidDecl(); 5478 } 5479 } 5480 } 5481 } 5482 5483 // FIXME: We need to pass in the attributes given an AST 5484 // representation, not a parser representation. 5485 if (D) 5486 // FIXME: What to pass instead of TUScope? 5487 ProcessDeclAttributes(TUScope, NewFD, *D); 5488 5489 if (T.isObjCGCWeak()) 5490 Diag(Loc, diag::warn_attribute_weak_on_field); 5491 5492 NewFD->setAccess(AS); 5493 5494 // C++ [dcl.init.aggr]p1: 5495 // An aggregate is an array or a class (clause 9) with [...] no 5496 // private or protected non-static data members (clause 11). 5497 // A POD must be an aggregate. 5498 if (getLangOptions().CPlusPlus && 5499 (AS == AS_private || AS == AS_protected)) { 5500 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5501 CXXRecord->setAggregate(false); 5502 CXXRecord->setPOD(false); 5503 } 5504 5505 return NewFD; 5506} 5507 5508/// DiagnoseNontrivial - Given that a class has a non-trivial 5509/// special member, figure out why. 5510void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5511 QualType QT(T, 0U); 5512 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5513 5514 // Check whether the member was user-declared. 5515 switch (member) { 5516 case CXXDefaultConstructor: 5517 if (RD->hasUserDeclaredConstructor()) { 5518 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5519 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5520 const FunctionDecl *body = 0; 5521 ci->getBody(body); 5522 if (!body || 5523 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5524 SourceLocation CtorLoc = ci->getLocation(); 5525 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5526 return; 5527 } 5528 } 5529 5530 assert(0 && "found no user-declared constructors"); 5531 return; 5532 } 5533 break; 5534 5535 case CXXCopyConstructor: 5536 if (RD->hasUserDeclaredCopyConstructor()) { 5537 SourceLocation CtorLoc = 5538 RD->getCopyConstructor(Context, 0)->getLocation(); 5539 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5540 return; 5541 } 5542 break; 5543 5544 case CXXCopyAssignment: 5545 if (RD->hasUserDeclaredCopyAssignment()) { 5546 // FIXME: this should use the location of the copy 5547 // assignment, not the type. 5548 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5549 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5550 return; 5551 } 5552 break; 5553 5554 case CXXDestructor: 5555 if (RD->hasUserDeclaredDestructor()) { 5556 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5557 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5558 return; 5559 } 5560 break; 5561 } 5562 5563 typedef CXXRecordDecl::base_class_iterator base_iter; 5564 5565 // Virtual bases and members inhibit trivial copying/construction, 5566 // but not trivial destruction. 5567 if (member != CXXDestructor) { 5568 // Check for virtual bases. vbases includes indirect virtual bases, 5569 // so we just iterate through the direct bases. 5570 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5571 if (bi->isVirtual()) { 5572 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5573 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5574 return; 5575 } 5576 5577 // Check for virtual methods. 5578 typedef CXXRecordDecl::method_iterator meth_iter; 5579 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5580 ++mi) { 5581 if (mi->isVirtual()) { 5582 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5583 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5584 return; 5585 } 5586 } 5587 } 5588 5589 bool (CXXRecordDecl::*hasTrivial)() const; 5590 switch (member) { 5591 case CXXDefaultConstructor: 5592 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5593 case CXXCopyConstructor: 5594 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5595 case CXXCopyAssignment: 5596 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5597 case CXXDestructor: 5598 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5599 default: 5600 assert(0 && "unexpected special member"); return; 5601 } 5602 5603 // Check for nontrivial bases (and recurse). 5604 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5605 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5606 assert(BaseRT && "Don't know how to handle dependent bases"); 5607 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5608 if (!(BaseRecTy->*hasTrivial)()) { 5609 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5610 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5611 DiagnoseNontrivial(BaseRT, member); 5612 return; 5613 } 5614 } 5615 5616 // Check for nontrivial members (and recurse). 5617 typedef RecordDecl::field_iterator field_iter; 5618 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5619 ++fi) { 5620 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5621 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5622 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5623 5624 if (!(EltRD->*hasTrivial)()) { 5625 SourceLocation FLoc = (*fi)->getLocation(); 5626 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5627 DiagnoseNontrivial(EltRT, member); 5628 return; 5629 } 5630 } 5631 } 5632 5633 assert(0 && "found no explanation for non-trivial member"); 5634} 5635 5636/// TranslateIvarVisibility - Translate visibility from a token ID to an 5637/// AST enum value. 5638static ObjCIvarDecl::AccessControl 5639TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5640 switch (ivarVisibility) { 5641 default: assert(0 && "Unknown visitibility kind"); 5642 case tok::objc_private: return ObjCIvarDecl::Private; 5643 case tok::objc_public: return ObjCIvarDecl::Public; 5644 case tok::objc_protected: return ObjCIvarDecl::Protected; 5645 case tok::objc_package: return ObjCIvarDecl::Package; 5646 } 5647} 5648 5649/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5650/// in order to create an IvarDecl object for it. 5651Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5652 SourceLocation DeclStart, 5653 DeclPtrTy IntfDecl, 5654 Declarator &D, ExprTy *BitfieldWidth, 5655 tok::ObjCKeywordKind Visibility) { 5656 5657 IdentifierInfo *II = D.getIdentifier(); 5658 Expr *BitWidth = (Expr*)BitfieldWidth; 5659 SourceLocation Loc = DeclStart; 5660 if (II) Loc = D.getIdentifierLoc(); 5661 5662 // FIXME: Unnamed fields can be handled in various different ways, for 5663 // example, unnamed unions inject all members into the struct namespace! 5664 5665 TypeSourceInfo *TInfo = 0; 5666 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5667 5668 if (BitWidth) { 5669 // 6.7.2.1p3, 6.7.2.1p4 5670 if (VerifyBitField(Loc, II, T, BitWidth)) { 5671 D.setInvalidType(); 5672 DeleteExpr(BitWidth); 5673 BitWidth = 0; 5674 } 5675 } else { 5676 // Not a bitfield. 5677 5678 // validate II. 5679 5680 } 5681 5682 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5683 // than a variably modified type. 5684 if (T->isVariablyModifiedType()) { 5685 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5686 D.setInvalidType(); 5687 } 5688 5689 // Get the visibility (access control) for this ivar. 5690 ObjCIvarDecl::AccessControl ac = 5691 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5692 : ObjCIvarDecl::None; 5693 // Must set ivar's DeclContext to its enclosing interface. 5694 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5695 DeclContext *EnclosingContext; 5696 if (ObjCImplementationDecl *IMPDecl = 5697 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5698 // Case of ivar declared in an implementation. Context is that of its class. 5699 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5700 assert(IDecl && "No class- ActOnIvar"); 5701 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5702 } else 5703 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5704 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5705 5706 // Construct the decl. 5707 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5708 EnclosingContext, Loc, II, T, 5709 TInfo, ac, (Expr *)BitfieldWidth); 5710 5711 if (II) { 5712 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5713 ForRedeclaration); 5714 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5715 && !isa<TagDecl>(PrevDecl)) { 5716 Diag(Loc, diag::err_duplicate_member) << II; 5717 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5718 NewID->setInvalidDecl(); 5719 } 5720 } 5721 5722 // Process attributes attached to the ivar. 5723 ProcessDeclAttributes(S, NewID, D); 5724 5725 if (D.isInvalidType()) 5726 NewID->setInvalidDecl(); 5727 5728 if (II) { 5729 // FIXME: When interfaces are DeclContexts, we'll need to add 5730 // these to the interface. 5731 S->AddDecl(DeclPtrTy::make(NewID)); 5732 IdResolver.AddDecl(NewID); 5733 } 5734 5735 return DeclPtrTy::make(NewID); 5736} 5737 5738void Sema::ActOnFields(Scope* S, 5739 SourceLocation RecLoc, DeclPtrTy RecDecl, 5740 DeclPtrTy *Fields, unsigned NumFields, 5741 SourceLocation LBrac, SourceLocation RBrac, 5742 AttributeList *Attr) { 5743 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5744 assert(EnclosingDecl && "missing record or interface decl"); 5745 5746 // If the decl this is being inserted into is invalid, then it may be a 5747 // redeclaration or some other bogus case. Don't try to add fields to it. 5748 if (EnclosingDecl->isInvalidDecl()) { 5749 // FIXME: Deallocate fields? 5750 return; 5751 } 5752 5753 5754 // Verify that all the fields are okay. 5755 unsigned NumNamedMembers = 0; 5756 llvm::SmallVector<FieldDecl*, 32> RecFields; 5757 5758 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5759 for (unsigned i = 0; i != NumFields; ++i) { 5760 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5761 5762 // Get the type for the field. 5763 Type *FDTy = FD->getType().getTypePtr(); 5764 5765 if (!FD->isAnonymousStructOrUnion()) { 5766 // Remember all fields written by the user. 5767 RecFields.push_back(FD); 5768 } 5769 5770 // If the field is already invalid for some reason, don't emit more 5771 // diagnostics about it. 5772 if (FD->isInvalidDecl()) { 5773 EnclosingDecl->setInvalidDecl(); 5774 continue; 5775 } 5776 5777 // C99 6.7.2.1p2: 5778 // A structure or union shall not contain a member with 5779 // incomplete or function type (hence, a structure shall not 5780 // contain an instance of itself, but may contain a pointer to 5781 // an instance of itself), except that the last member of a 5782 // structure with more than one named member may have incomplete 5783 // array type; such a structure (and any union containing, 5784 // possibly recursively, a member that is such a structure) 5785 // shall not be a member of a structure or an element of an 5786 // array. 5787 if (FDTy->isFunctionType()) { 5788 // Field declared as a function. 5789 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5790 << FD->getDeclName(); 5791 FD->setInvalidDecl(); 5792 EnclosingDecl->setInvalidDecl(); 5793 continue; 5794 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5795 Record && Record->isStruct()) { 5796 // Flexible array member. 5797 if (NumNamedMembers < 1) { 5798 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5799 << FD->getDeclName(); 5800 FD->setInvalidDecl(); 5801 EnclosingDecl->setInvalidDecl(); 5802 continue; 5803 } 5804 // Okay, we have a legal flexible array member at the end of the struct. 5805 if (Record) 5806 Record->setHasFlexibleArrayMember(true); 5807 } else if (!FDTy->isDependentType() && 5808 RequireCompleteType(FD->getLocation(), FD->getType(), 5809 diag::err_field_incomplete)) { 5810 // Incomplete type 5811 FD->setInvalidDecl(); 5812 EnclosingDecl->setInvalidDecl(); 5813 continue; 5814 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5815 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5816 // If this is a member of a union, then entire union becomes "flexible". 5817 if (Record && Record->isUnion()) { 5818 Record->setHasFlexibleArrayMember(true); 5819 } else { 5820 // If this is a struct/class and this is not the last element, reject 5821 // it. Note that GCC supports variable sized arrays in the middle of 5822 // structures. 5823 if (i != NumFields-1) 5824 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5825 << FD->getDeclName() << FD->getType(); 5826 else { 5827 // We support flexible arrays at the end of structs in 5828 // other structs as an extension. 5829 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5830 << FD->getDeclName(); 5831 if (Record) 5832 Record->setHasFlexibleArrayMember(true); 5833 } 5834 } 5835 } 5836 if (Record && FDTTy->getDecl()->hasObjectMember()) 5837 Record->setHasObjectMember(true); 5838 } else if (FDTy->isObjCInterfaceType()) { 5839 /// A field cannot be an Objective-c object 5840 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5841 FD->setInvalidDecl(); 5842 EnclosingDecl->setInvalidDecl(); 5843 continue; 5844 } else if (getLangOptions().ObjC1 && 5845 getLangOptions().getGCMode() != LangOptions::NonGC && 5846 Record && 5847 (FD->getType()->isObjCObjectPointerType() || 5848 FD->getType().isObjCGCStrong())) 5849 Record->setHasObjectMember(true); 5850 // Keep track of the number of named members. 5851 if (FD->getIdentifier()) 5852 ++NumNamedMembers; 5853 } 5854 5855 // Okay, we successfully defined 'Record'. 5856 if (Record) { 5857 Record->completeDefinition(); 5858 } else { 5859 ObjCIvarDecl **ClsFields = 5860 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5861 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5862 ID->setLocEnd(RBrac); 5863 // Add ivar's to class's DeclContext. 5864 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5865 ClsFields[i]->setLexicalDeclContext(ID); 5866 ID->addDecl(ClsFields[i]); 5867 } 5868 // Must enforce the rule that ivars in the base classes may not be 5869 // duplicates. 5870 if (ID->getSuperClass()) 5871 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 5872 } else if (ObjCImplementationDecl *IMPDecl = 5873 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5874 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5875 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5876 // Ivar declared in @implementation never belongs to the implementation. 5877 // Only it is in implementation's lexical context. 5878 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5879 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5880 } else if (ObjCCategoryDecl *CDecl = 5881 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 5882 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) 5883 Diag(LBrac, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 5884 else { 5885 // FIXME. Class extension does not have a LocEnd field. 5886 // CDecl->setLocEnd(RBrac); 5887 // Add ivar's to class extension's DeclContext. 5888 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5889 ClsFields[i]->setLexicalDeclContext(CDecl); 5890 CDecl->addDecl(ClsFields[i]); 5891 } 5892 } 5893 } 5894 } 5895 5896 if (Attr) 5897 ProcessDeclAttributeList(S, Record, Attr); 5898} 5899 5900/// \brief Determine whether the given integral value is representable within 5901/// the given type T. 5902static bool isRepresentableIntegerValue(ASTContext &Context, 5903 llvm::APSInt &Value, 5904 QualType T) { 5905 assert(T->isIntegralType() && "Integral type required!"); 5906 unsigned BitWidth = Context.getTypeSize(T); 5907 5908 if (Value.isUnsigned() || Value.isNonNegative()) 5909 return Value.getActiveBits() < BitWidth; 5910 5911 return Value.getMinSignedBits() <= BitWidth; 5912} 5913 5914// \brief Given an integral type, return the next larger integral type 5915// (or a NULL type of no such type exists). 5916static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 5917 // FIXME: Int128/UInt128 support, which also needs to be introduced into 5918 // enum checking below. 5919 assert(T->isIntegralType() && "Integral type required!"); 5920 const unsigned NumTypes = 4; 5921 QualType SignedIntegralTypes[NumTypes] = { 5922 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 5923 }; 5924 QualType UnsignedIntegralTypes[NumTypes] = { 5925 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 5926 Context.UnsignedLongLongTy 5927 }; 5928 5929 unsigned BitWidth = Context.getTypeSize(T); 5930 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 5931 : UnsignedIntegralTypes; 5932 for (unsigned I = 0; I != NumTypes; ++I) 5933 if (Context.getTypeSize(Types[I]) > BitWidth) 5934 return Types[I]; 5935 5936 return QualType(); 5937} 5938 5939EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5940 EnumConstantDecl *LastEnumConst, 5941 SourceLocation IdLoc, 5942 IdentifierInfo *Id, 5943 ExprArg val) { 5944 Expr *Val = (Expr *)val.get(); 5945 5946 unsigned IntWidth = Context.Target.getIntWidth(); 5947 llvm::APSInt EnumVal(IntWidth); 5948 QualType EltTy; 5949 if (Val) { 5950 if (Enum->isDependentType() || Val->isTypeDependent()) 5951 EltTy = Context.DependentTy; 5952 else { 5953 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5954 SourceLocation ExpLoc; 5955 if (!Val->isValueDependent() && 5956 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5957 Val = 0; 5958 } else { 5959 if (!getLangOptions().CPlusPlus) { 5960 // C99 6.7.2.2p2: 5961 // The expression that defines the value of an enumeration constant 5962 // shall be an integer constant expression that has a value 5963 // representable as an int. 5964 5965 // Complain if the value is not representable in an int. 5966 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 5967 Diag(IdLoc, diag::ext_enum_value_not_int) 5968 << EnumVal.toString(10) << Val->getSourceRange() 5969 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 5970 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 5971 // Force the type of the expression to 'int'. 5972 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 5973 5974 if (Val != val.get()) { 5975 val.release(); 5976 val = Val; 5977 } 5978 } 5979 } 5980 5981 // C++0x [dcl.enum]p5: 5982 // If the underlying type is not fixed, the type of each enumerator 5983 // is the type of its initializing value: 5984 // - If an initializer is specified for an enumerator, the 5985 // initializing value has the same type as the expression. 5986 EltTy = Val->getType(); 5987 } 5988 } 5989 } 5990 5991 if (!Val) { 5992 if (Enum->isDependentType()) 5993 EltTy = Context.DependentTy; 5994 else if (!LastEnumConst) { 5995 // C++0x [dcl.enum]p5: 5996 // If the underlying type is not fixed, the type of each enumerator 5997 // is the type of its initializing value: 5998 // - If no initializer is specified for the first enumerator, the 5999 // initializing value has an unspecified integral type. 6000 // 6001 // GCC uses 'int' for its unspecified integral type, as does 6002 // C99 6.7.2.2p3. 6003 EltTy = Context.IntTy; 6004 } else { 6005 // Assign the last value + 1. 6006 EnumVal = LastEnumConst->getInitVal(); 6007 ++EnumVal; 6008 EltTy = LastEnumConst->getType(); 6009 6010 // Check for overflow on increment. 6011 if (EnumVal < LastEnumConst->getInitVal()) { 6012 // C++0x [dcl.enum]p5: 6013 // If the underlying type is not fixed, the type of each enumerator 6014 // is the type of its initializing value: 6015 // 6016 // - Otherwise the type of the initializing value is the same as 6017 // the type of the initializing value of the preceding enumerator 6018 // unless the incremented value is not representable in that type, 6019 // in which case the type is an unspecified integral type 6020 // sufficient to contain the incremented value. If no such type 6021 // exists, the program is ill-formed. 6022 QualType T = getNextLargerIntegralType(Context, EltTy); 6023 if (T.isNull()) { 6024 // There is no integral type larger enough to represent this 6025 // value. Complain, then allow the value to wrap around. 6026 EnumVal = LastEnumConst->getInitVal(); 6027 EnumVal.zext(EnumVal.getBitWidth() * 2); 6028 Diag(IdLoc, diag::warn_enumerator_too_large) 6029 << EnumVal.toString(10); 6030 } else { 6031 EltTy = T; 6032 } 6033 6034 // Retrieve the last enumerator's value, extent that type to the 6035 // type that is supposed to be large enough to represent the incremented 6036 // value, then increment. 6037 EnumVal = LastEnumConst->getInitVal(); 6038 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6039 EnumVal.zextOrTrunc(Context.getTypeSize(EltTy)); 6040 ++EnumVal; 6041 6042 // If we're not in C++, diagnose the overflow of enumerator values, 6043 // which in C99 means that the enumerator value is not representable in 6044 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6045 // permits enumerator values that are representable in some larger 6046 // integral type. 6047 if (!getLangOptions().CPlusPlus && !T.isNull()) 6048 Diag(IdLoc, diag::warn_enum_value_overflow); 6049 } else if (!getLangOptions().CPlusPlus && 6050 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6051 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6052 Diag(IdLoc, diag::ext_enum_value_not_int) 6053 << EnumVal.toString(10) << 1; 6054 } 6055 } 6056 } 6057 6058 if (!EltTy->isDependentType()) { 6059 // Make the enumerator value match the signedness and size of the 6060 // enumerator's type. 6061 EnumVal.zextOrTrunc(Context.getTypeSize(EltTy)); 6062 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6063 } 6064 6065 val.release(); 6066 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6067 Val, EnumVal); 6068} 6069 6070 6071Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6072 DeclPtrTy lastEnumConst, 6073 SourceLocation IdLoc, 6074 IdentifierInfo *Id, 6075 SourceLocation EqualLoc, ExprTy *val) { 6076 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6077 EnumConstantDecl *LastEnumConst = 6078 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6079 Expr *Val = static_cast<Expr*>(val); 6080 6081 // The scope passed in may not be a decl scope. Zip up the scope tree until 6082 // we find one that is. 6083 S = getNonFieldDeclScope(S); 6084 6085 // Verify that there isn't already something declared with this name in this 6086 // scope. 6087 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName, 6088 ForRedeclaration); 6089 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6090 // Maybe we will complain about the shadowed template parameter. 6091 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6092 // Just pretend that we didn't see the previous declaration. 6093 PrevDecl = 0; 6094 } 6095 6096 if (PrevDecl) { 6097 // When in C++, we may get a TagDecl with the same name; in this case the 6098 // enum constant will 'hide' the tag. 6099 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6100 "Received TagDecl when not in C++!"); 6101 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6102 if (isa<EnumConstantDecl>(PrevDecl)) 6103 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6104 else 6105 Diag(IdLoc, diag::err_redefinition) << Id; 6106 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6107 if (Val) Val->Destroy(Context); 6108 return DeclPtrTy(); 6109 } 6110 } 6111 6112 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6113 IdLoc, Id, Owned(Val)); 6114 6115 // Register this decl in the current scope stack. 6116 if (New) { 6117 New->setAccess(TheEnumDecl->getAccess()); 6118 PushOnScopeChains(New, S); 6119 } 6120 6121 return DeclPtrTy::make(New); 6122} 6123 6124void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6125 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6126 DeclPtrTy *Elements, unsigned NumElements, 6127 Scope *S, AttributeList *Attr) { 6128 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6129 QualType EnumType = Context.getTypeDeclType(Enum); 6130 6131 if (Attr) 6132 ProcessDeclAttributeList(S, Enum, Attr); 6133 6134 if (Enum->isDependentType()) { 6135 for (unsigned i = 0; i != NumElements; ++i) { 6136 EnumConstantDecl *ECD = 6137 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6138 if (!ECD) continue; 6139 6140 ECD->setType(EnumType); 6141 } 6142 6143 Enum->completeDefinition(Context.DependentTy, Context.DependentTy); 6144 return; 6145 } 6146 6147 // TODO: If the result value doesn't fit in an int, it must be a long or long 6148 // long value. ISO C does not support this, but GCC does as an extension, 6149 // emit a warning. 6150 unsigned IntWidth = Context.Target.getIntWidth(); 6151 unsigned CharWidth = Context.Target.getCharWidth(); 6152 unsigned ShortWidth = Context.Target.getShortWidth(); 6153 6154 // Verify that all the values are okay, compute the size of the values, and 6155 // reverse the list. 6156 unsigned NumNegativeBits = 0; 6157 unsigned NumPositiveBits = 0; 6158 6159 // Keep track of whether all elements have type int. 6160 bool AllElementsInt = true; 6161 6162 for (unsigned i = 0; i != NumElements; ++i) { 6163 EnumConstantDecl *ECD = 6164 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6165 if (!ECD) continue; // Already issued a diagnostic. 6166 6167 const llvm::APSInt &InitVal = ECD->getInitVal(); 6168 6169 // Keep track of the size of positive and negative values. 6170 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6171 NumPositiveBits = std::max(NumPositiveBits, 6172 (unsigned)InitVal.getActiveBits()); 6173 else 6174 NumNegativeBits = std::max(NumNegativeBits, 6175 (unsigned)InitVal.getMinSignedBits()); 6176 6177 // Keep track of whether every enum element has type int (very commmon). 6178 if (AllElementsInt) 6179 AllElementsInt = ECD->getType() == Context.IntTy; 6180 } 6181 6182 // Figure out the type that should be used for this enum. 6183 // FIXME: Support -fshort-enums. 6184 QualType BestType; 6185 unsigned BestWidth; 6186 6187 // C++0x N3000 [conv.prom]p3: 6188 // An rvalue of an unscoped enumeration type whose underlying 6189 // type is not fixed can be converted to an rvalue of the first 6190 // of the following types that can represent all the values of 6191 // the enumeration: int, unsigned int, long int, unsigned long 6192 // int, long long int, or unsigned long long int. 6193 // C99 6.4.4.3p2: 6194 // An identifier declared as an enumeration constant has type int. 6195 // The C99 rule is modified by a gcc extension 6196 QualType BestPromotionType; 6197 6198 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6199 6200 if (NumNegativeBits) { 6201 // If there is a negative value, figure out the smallest integer type (of 6202 // int/long/longlong) that fits. 6203 // If it's packed, check also if it fits a char or a short. 6204 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6205 BestType = Context.SignedCharTy; 6206 BestWidth = CharWidth; 6207 } else if (Packed && NumNegativeBits <= ShortWidth && 6208 NumPositiveBits < ShortWidth) { 6209 BestType = Context.ShortTy; 6210 BestWidth = ShortWidth; 6211 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6212 BestType = Context.IntTy; 6213 BestWidth = IntWidth; 6214 } else { 6215 BestWidth = Context.Target.getLongWidth(); 6216 6217 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6218 BestType = Context.LongTy; 6219 } else { 6220 BestWidth = Context.Target.getLongLongWidth(); 6221 6222 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6223 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6224 BestType = Context.LongLongTy; 6225 } 6226 } 6227 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6228 } else { 6229 // If there is no negative value, figure out the smallest type that fits 6230 // all of the enumerator values. 6231 // If it's packed, check also if it fits a char or a short. 6232 if (Packed && NumPositiveBits <= CharWidth) { 6233 BestType = Context.UnsignedCharTy; 6234 BestPromotionType = Context.IntTy; 6235 BestWidth = CharWidth; 6236 } else if (Packed && NumPositiveBits <= ShortWidth) { 6237 BestType = Context.UnsignedShortTy; 6238 BestPromotionType = Context.IntTy; 6239 BestWidth = ShortWidth; 6240 } else if (NumPositiveBits <= IntWidth) { 6241 BestType = Context.UnsignedIntTy; 6242 BestWidth = IntWidth; 6243 BestPromotionType 6244 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6245 ? Context.UnsignedIntTy : Context.IntTy; 6246 } else if (NumPositiveBits <= 6247 (BestWidth = Context.Target.getLongWidth())) { 6248 BestType = Context.UnsignedLongTy; 6249 BestPromotionType 6250 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6251 ? Context.UnsignedLongTy : Context.LongTy; 6252 } else { 6253 BestWidth = Context.Target.getLongLongWidth(); 6254 assert(NumPositiveBits <= BestWidth && 6255 "How could an initializer get larger than ULL?"); 6256 BestType = Context.UnsignedLongLongTy; 6257 BestPromotionType 6258 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6259 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6260 } 6261 } 6262 6263 // Loop over all of the enumerator constants, changing their types to match 6264 // the type of the enum if needed. 6265 for (unsigned i = 0; i != NumElements; ++i) { 6266 EnumConstantDecl *ECD = 6267 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6268 if (!ECD) continue; // Already issued a diagnostic. 6269 6270 // Standard C says the enumerators have int type, but we allow, as an 6271 // extension, the enumerators to be larger than int size. If each 6272 // enumerator value fits in an int, type it as an int, otherwise type it the 6273 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6274 // that X has type 'int', not 'unsigned'. 6275 6276 // Determine whether the value fits into an int. 6277 llvm::APSInt InitVal = ECD->getInitVal(); 6278 6279 // If it fits into an integer type, force it. Otherwise force it to match 6280 // the enum decl type. 6281 QualType NewTy; 6282 unsigned NewWidth; 6283 bool NewSign; 6284 if (!getLangOptions().CPlusPlus && 6285 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6286 NewTy = Context.IntTy; 6287 NewWidth = IntWidth; 6288 NewSign = true; 6289 } else if (ECD->getType() == BestType) { 6290 // Already the right type! 6291 if (getLangOptions().CPlusPlus) 6292 // C++ [dcl.enum]p4: Following the closing brace of an 6293 // enum-specifier, each enumerator has the type of its 6294 // enumeration. 6295 ECD->setType(EnumType); 6296 continue; 6297 } else { 6298 NewTy = BestType; 6299 NewWidth = BestWidth; 6300 NewSign = BestType->isSignedIntegerType(); 6301 } 6302 6303 // Adjust the APSInt value. 6304 InitVal.extOrTrunc(NewWidth); 6305 InitVal.setIsSigned(NewSign); 6306 ECD->setInitVal(InitVal); 6307 6308 // Adjust the Expr initializer and type. 6309 if (ECD->getInitExpr()) 6310 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6311 CastExpr::CK_IntegralCast, 6312 ECD->getInitExpr(), 6313 /*isLvalue=*/false)); 6314 if (getLangOptions().CPlusPlus) 6315 // C++ [dcl.enum]p4: Following the closing brace of an 6316 // enum-specifier, each enumerator has the type of its 6317 // enumeration. 6318 ECD->setType(EnumType); 6319 else 6320 ECD->setType(NewTy); 6321 } 6322 6323 Enum->completeDefinition(BestType, BestPromotionType); 6324} 6325 6326Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6327 ExprArg expr) { 6328 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6329 6330 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6331 Loc, AsmString); 6332 CurContext->addDecl(New); 6333 return DeclPtrTy::make(New); 6334} 6335 6336void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6337 SourceLocation PragmaLoc, 6338 SourceLocation NameLoc) { 6339 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6340 6341 if (PrevDecl) { 6342 PrevDecl->addAttr(::new (Context) WeakAttr()); 6343 } else { 6344 (void)WeakUndeclaredIdentifiers.insert( 6345 std::pair<IdentifierInfo*,WeakInfo> 6346 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6347 } 6348} 6349 6350void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6351 IdentifierInfo* AliasName, 6352 SourceLocation PragmaLoc, 6353 SourceLocation NameLoc, 6354 SourceLocation AliasNameLoc) { 6355 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6356 WeakInfo W = WeakInfo(Name, NameLoc); 6357 6358 if (PrevDecl) { 6359 if (!PrevDecl->hasAttr<AliasAttr>()) 6360 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6361 DeclApplyPragmaWeak(TUScope, ND, W); 6362 } else { 6363 (void)WeakUndeclaredIdentifiers.insert( 6364 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6365 } 6366} 6367