SemaDecl.cpp revision e885e188b25dc218132402d1f48fb35e175bfb2e
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 "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "TypeLocBuilder.h" 21#include "clang/AST/APValue.h" 22#include "clang/AST/ASTConsumer.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclCXX.h" 26#include "clang/AST/DeclObjC.h" 27#include "clang/AST/DeclTemplate.h" 28#include "clang/AST/EvaluatedExprVisitor.h" 29#include "clang/AST/ExprCXX.h" 30#include "clang/AST/StmtCXX.h" 31#include "clang/AST/CharUnits.h" 32#include "clang/Sema/DeclSpec.h" 33#include "clang/Sema/ParsedTemplate.h" 34#include "clang/Parse/ParseDiagnostic.h" 35#include "clang/Basic/PartialDiagnostic.h" 36#include "clang/Basic/SourceManager.h" 37#include "clang/Basic/TargetInfo.h" 38// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 39#include "clang/Lex/Preprocessor.h" 40#include "clang/Lex/HeaderSearch.h" 41#include "llvm/ADT/Triple.h" 42#include <algorithm> 43#include <cstring> 44#include <functional> 45using namespace clang; 46using namespace sema; 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 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. 63ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, bool HasTrailingDot, 66 ParsedType ObjectTypePtr, 67 bool WantNontrivialTypeSourceInfo) { 68 // Determine where we will perform name lookup. 69 DeclContext *LookupCtx = 0; 70 if (ObjectTypePtr) { 71 QualType ObjectType = ObjectTypePtr.get(); 72 if (ObjectType->isRecordType()) 73 LookupCtx = computeDeclContext(ObjectType); 74 } else if (SS && SS->isNotEmpty()) { 75 LookupCtx = computeDeclContext(*SS, false); 76 77 if (!LookupCtx) { 78 if (isDependentScopeSpecifier(*SS)) { 79 // C++ [temp.res]p3: 80 // A qualified-id that refers to a type and in which the 81 // nested-name-specifier depends on a template-parameter (14.6.2) 82 // shall be prefixed by the keyword typename to indicate that the 83 // qualified-id denotes a type, forming an 84 // elaborated-type-specifier (7.1.5.3). 85 // 86 // We therefore do not perform any name lookup if the result would 87 // refer to a member of an unknown specialization. 88 if (!isClassName) 89 return ParsedType(); 90 91 // We know from the grammar that this name refers to a type, 92 // so build a dependent node to describe the type. 93 if (WantNontrivialTypeSourceInfo) 94 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 95 96 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 97 QualType T = 98 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 99 II, NameLoc); 100 101 return ParsedType::make(T); 102 } 103 104 return ParsedType(); 105 } 106 107 if (!LookupCtx->isDependentContext() && 108 RequireCompleteDeclContext(*SS, LookupCtx)) 109 return ParsedType(); 110 } 111 112 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 113 // lookup for class-names. 114 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 115 LookupOrdinaryName; 116 LookupResult Result(*this, &II, NameLoc, Kind); 117 if (LookupCtx) { 118 // Perform "qualified" name lookup into the declaration context we 119 // computed, which is either the type of the base of a member access 120 // expression or the declaration context associated with a prior 121 // nested-name-specifier. 122 LookupQualifiedName(Result, LookupCtx); 123 124 if (ObjectTypePtr && Result.empty()) { 125 // C++ [basic.lookup.classref]p3: 126 // If the unqualified-id is ~type-name, the type-name is looked up 127 // in the context of the entire postfix-expression. If the type T of 128 // the object expression is of a class type C, the type-name is also 129 // looked up in the scope of class C. At least one of the lookups shall 130 // find a name that refers to (possibly cv-qualified) T. 131 LookupName(Result, S); 132 } 133 } else { 134 // Perform unqualified name lookup. 135 LookupName(Result, S); 136 } 137 138 NamedDecl *IIDecl = 0; 139 switch (Result.getResultKind()) { 140 case LookupResult::NotFound: 141 case LookupResult::NotFoundInCurrentInstantiation: 142 case LookupResult::FoundOverloaded: 143 case LookupResult::FoundUnresolvedValue: 144 Result.suppressDiagnostics(); 145 return ParsedType(); 146 147 case LookupResult::Ambiguous: 148 // Recover from type-hiding ambiguities by hiding the type. We'll 149 // do the lookup again when looking for an object, and we can 150 // diagnose the error then. If we don't do this, then the error 151 // about hiding the type will be immediately followed by an error 152 // that only makes sense if the identifier was treated like a type. 153 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 154 Result.suppressDiagnostics(); 155 return ParsedType(); 156 } 157 158 // Look to see if we have a type anywhere in the list of results. 159 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 160 Res != ResEnd; ++Res) { 161 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 162 if (!IIDecl || 163 (*Res)->getLocation().getRawEncoding() < 164 IIDecl->getLocation().getRawEncoding()) 165 IIDecl = *Res; 166 } 167 } 168 169 if (!IIDecl) { 170 // None of the entities we found is a type, so there is no way 171 // to even assume that the result is a type. In this case, don't 172 // complain about the ambiguity. The parser will either try to 173 // perform this lookup again (e.g., as an object name), which 174 // will produce the ambiguity, or will complain that it expected 175 // a type name. 176 Result.suppressDiagnostics(); 177 return ParsedType(); 178 } 179 180 // We found a type within the ambiguous lookup; diagnose the 181 // ambiguity and then return that type. This might be the right 182 // answer, or it might not be, but it suppresses any attempt to 183 // perform the name lookup again. 184 break; 185 186 case LookupResult::Found: 187 IIDecl = Result.getFoundDecl(); 188 break; 189 } 190 191 assert(IIDecl && "Didn't find decl"); 192 193 QualType T; 194 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 195 DiagnoseUseOfDecl(IIDecl, NameLoc); 196 197 if (T.isNull()) 198 T = Context.getTypeDeclType(TD); 199 200 if (SS && SS->isNotEmpty()) { 201 if (WantNontrivialTypeSourceInfo) { 202 // Construct a type with type-source information. 203 TypeLocBuilder Builder; 204 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 205 206 T = getElaboratedType(ETK_None, *SS, T); 207 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 208 ElabTL.setKeywordLoc(SourceLocation()); 209 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 210 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 211 } else { 212 T = getElaboratedType(ETK_None, *SS, T); 213 } 214 } 215 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 216 (void)DiagnoseUseOfDecl(IDecl, NameLoc); 217 if (!HasTrailingDot) 218 T = Context.getObjCInterfaceType(IDecl); 219 } 220 221 if (T.isNull()) { 222 // If it's not plausibly a type, suppress diagnostics. 223 Result.suppressDiagnostics(); 224 return ParsedType(); 225 } 226 return ParsedType::make(T); 227} 228 229/// isTagName() - This method is called *for error recovery purposes only* 230/// to determine if the specified name is a valid tag name ("struct foo"). If 231/// so, this returns the TST for the tag corresponding to it (TST_enum, 232/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 233/// where the user forgot to specify the tag. 234DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 235 // Do a tag name lookup in this scope. 236 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 237 LookupName(R, S, false); 238 R.suppressDiagnostics(); 239 if (R.getResultKind() == LookupResult::Found) 240 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 241 switch (TD->getTagKind()) { 242 default: return DeclSpec::TST_unspecified; 243 case TTK_Struct: return DeclSpec::TST_struct; 244 case TTK_Union: return DeclSpec::TST_union; 245 case TTK_Class: return DeclSpec::TST_class; 246 case TTK_Enum: return DeclSpec::TST_enum; 247 } 248 } 249 250 return DeclSpec::TST_unspecified; 251} 252 253/// isMicrosoftMissingTypename - In Microsoft mode, within class scope, 254/// if a CXXScopeSpec's type is equal to the type of one of the base classes 255/// then downgrade the missing typename error to a warning. 256/// This is needed for MSVC compatibility; Example: 257/// @code 258/// template<class T> class A { 259/// public: 260/// typedef int TYPE; 261/// }; 262/// template<class T> class B : public A<T> { 263/// public: 264/// A<T>::TYPE a; // no typename required because A<T> is a base class. 265/// }; 266/// @endcode 267bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS) { 268 if (CurContext->isRecord()) { 269 const Type *Ty = SS->getScopeRep()->getAsType(); 270 271 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext); 272 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 273 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) 274 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base->getType())) 275 return true; 276 } 277 return false; 278} 279 280bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 281 SourceLocation IILoc, 282 Scope *S, 283 CXXScopeSpec *SS, 284 ParsedType &SuggestedType) { 285 // We don't have anything to suggest (yet). 286 SuggestedType = ParsedType(); 287 288 // There may have been a typo in the name of the type. Look up typo 289 // results, in case we have something that we can suggest. 290 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 291 NotForRedeclaration); 292 293 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 294 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 295 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 296 !Result->isInvalidDecl()) { 297 // We found a similarly-named type or interface; suggest that. 298 if (!SS || !SS->isSet()) 299 Diag(IILoc, diag::err_unknown_typename_suggest) 300 << &II << Lookup.getLookupName() 301 << FixItHint::CreateReplacement(SourceRange(IILoc), 302 Result->getNameAsString()); 303 else if (DeclContext *DC = computeDeclContext(*SS, false)) 304 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 305 << &II << DC << Lookup.getLookupName() << SS->getRange() 306 << FixItHint::CreateReplacement(SourceRange(IILoc), 307 Result->getNameAsString()); 308 else 309 llvm_unreachable("could not have corrected a typo here"); 310 311 Diag(Result->getLocation(), diag::note_previous_decl) 312 << Result->getDeclName(); 313 314 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 315 false, false, ParsedType(), 316 /*NonTrivialTypeSourceInfo=*/true); 317 return true; 318 } 319 } else if (Lookup.empty()) { 320 // We corrected to a keyword. 321 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 322 Diag(IILoc, diag::err_unknown_typename_suggest) 323 << &II << Corrected; 324 return true; 325 } 326 } 327 328 if (getLangOptions().CPlusPlus) { 329 // See if II is a class template that the user forgot to pass arguments to. 330 UnqualifiedId Name; 331 Name.setIdentifier(&II, IILoc); 332 CXXScopeSpec EmptySS; 333 TemplateTy TemplateResult; 334 bool MemberOfUnknownSpecialization; 335 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 336 Name, ParsedType(), true, TemplateResult, 337 MemberOfUnknownSpecialization) == TNK_Type_template) { 338 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 339 Diag(IILoc, diag::err_template_missing_args) << TplName; 340 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 341 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 342 << TplDecl->getTemplateParameters()->getSourceRange(); 343 } 344 return true; 345 } 346 } 347 348 // FIXME: Should we move the logic that tries to recover from a missing tag 349 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 350 351 if (!SS || (!SS->isSet() && !SS->isInvalid())) 352 Diag(IILoc, diag::err_unknown_typename) << &II; 353 else if (DeclContext *DC = computeDeclContext(*SS, false)) 354 Diag(IILoc, diag::err_typename_nested_not_found) 355 << &II << DC << SS->getRange(); 356 else if (isDependentScopeSpecifier(*SS)) { 357 unsigned DiagID = diag::err_typename_missing; 358 if (getLangOptions().Microsoft && isMicrosoftMissingTypename(SS)) 359 DiagID = diag::warn_typename_missing; 360 361 Diag(SS->getRange().getBegin(), DiagID) 362 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 363 << SourceRange(SS->getRange().getBegin(), IILoc) 364 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 365 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 366 } else { 367 assert(SS && SS->isInvalid() && 368 "Invalid scope specifier has already been diagnosed"); 369 } 370 371 return true; 372} 373 374/// \brief Determine whether the given result set contains either a type name 375/// or 376static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) { 377 bool CheckTemplate = R.getSema().getLangOptions().CPlusPlus && 378 NextToken.is(tok::less); 379 380 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) { 381 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I)) 382 return true; 383 384 if (CheckTemplate && isa<TemplateDecl>(*I)) 385 return true; 386 } 387 388 return false; 389} 390 391Sema::NameClassification Sema::ClassifyName(Scope *S, 392 CXXScopeSpec &SS, 393 IdentifierInfo *&Name, 394 SourceLocation NameLoc, 395 const Token &NextToken) { 396 DeclarationNameInfo NameInfo(Name, NameLoc); 397 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 398 399 if (NextToken.is(tok::coloncolon)) { 400 BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(), 401 QualType(), false, SS, 0, false); 402 403 } 404 405 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); 406 LookupParsedName(Result, S, &SS, !CurMethod); 407 408 // Perform lookup for Objective-C instance variables (including automatically 409 // synthesized instance variables), if we're in an Objective-C method. 410 // FIXME: This lookup really, really needs to be folded in to the normal 411 // unqualified lookup mechanism. 412 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) { 413 ExprResult E = LookupInObjCMethod(Result, S, Name, true); 414 if (E.get() || E.isInvalid()) 415 return E; 416 417 // Synthesize ivars lazily. 418 if (getLangOptions().ObjCDefaultSynthProperties && 419 getLangOptions().ObjCNonFragileABI2) { 420 if (SynthesizeProvisionalIvar(Result, Name, NameLoc)) { 421 if (const ObjCPropertyDecl *Property = 422 canSynthesizeProvisionalIvar(Name)) { 423 Diag(NameLoc, diag::warn_synthesized_ivar_access) << Name; 424 Diag(Property->getLocation(), diag::note_property_declare); 425 } 426 427 // FIXME: This is strange. Shouldn't we just take the ivar returned 428 // from SynthesizeProvisionalIvar and continue with that? 429 E = LookupInObjCMethod(Result, S, Name, true); 430 if (E.get() || E.isInvalid()) 431 return E; 432 } 433 } 434 } 435 436 bool SecondTry = false; 437 bool IsFilteredTemplateName = false; 438 439Corrected: 440 switch (Result.getResultKind()) { 441 case LookupResult::NotFound: 442 // If an unqualified-id is followed by a '(', then we have a function 443 // call. 444 if (!SS.isSet() && NextToken.is(tok::l_paren)) { 445 // In C++, this is an ADL-only call. 446 // FIXME: Reference? 447 if (getLangOptions().CPlusPlus) 448 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true); 449 450 // C90 6.3.2.2: 451 // If the expression that precedes the parenthesized argument list in a 452 // function call consists solely of an identifier, and if no 453 // declaration is visible for this identifier, the identifier is 454 // implicitly declared exactly as if, in the innermost block containing 455 // the function call, the declaration 456 // 457 // extern int identifier (); 458 // 459 // appeared. 460 // 461 // We also allow this in C99 as an extension. 462 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) { 463 Result.addDecl(D); 464 Result.resolveKind(); 465 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false); 466 } 467 } 468 469 // In C, we first see whether there is a tag type by the same name, in 470 // which case it's likely that the user just forget to write "enum", 471 // "struct", or "union". 472 if (!getLangOptions().CPlusPlus && !SecondTry) { 473 Result.clear(LookupTagName); 474 LookupParsedName(Result, S, &SS); 475 if (TagDecl *Tag = Result.getAsSingle<TagDecl>()) { 476 const char *TagName = 0; 477 const char *FixItTagName = 0; 478 switch (Tag->getTagKind()) { 479 case TTK_Class: 480 TagName = "class"; 481 FixItTagName = "class "; 482 break; 483 484 case TTK_Enum: 485 TagName = "enum"; 486 FixItTagName = "enum "; 487 break; 488 489 case TTK_Struct: 490 TagName = "struct"; 491 FixItTagName = "struct "; 492 break; 493 494 case TTK_Union: 495 TagName = "union"; 496 FixItTagName = "union "; 497 break; 498 } 499 500 Diag(NameLoc, diag::err_use_of_tag_name_without_tag) 501 << Name << TagName << getLangOptions().CPlusPlus 502 << FixItHint::CreateInsertion(NameLoc, FixItTagName); 503 break; 504 } 505 506 Result.clear(LookupOrdinaryName); 507 } 508 509 // Perform typo correction to determine if there is another name that is 510 // close to this name. 511 if (!SecondTry) { 512 if (DeclarationName Corrected = CorrectTypo(Result, S, &SS)) { 513 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest; 514 unsigned QualifiedDiag = diag::err_no_member_suggest; 515 516 NamedDecl *FirstDecl = Result.empty()? 0 : *Result.begin(); 517 NamedDecl *UnderlyingFirstDecl 518 = FirstDecl? FirstDecl->getUnderlyingDecl() : 0; 519 if (getLangOptions().CPlusPlus && NextToken.is(tok::less) && 520 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) { 521 UnqualifiedDiag = diag::err_no_template_suggest; 522 QualifiedDiag = diag::err_no_member_template_suggest; 523 } else if (UnderlyingFirstDecl && 524 (isa<TypeDecl>(UnderlyingFirstDecl) || 525 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) || 526 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) { 527 UnqualifiedDiag = diag::err_unknown_typename_suggest; 528 QualifiedDiag = diag::err_unknown_nested_typename_suggest; 529 } 530 531 if (SS.isEmpty()) 532 Diag(NameLoc, UnqualifiedDiag) 533 << Name << Corrected 534 << FixItHint::CreateReplacement(NameLoc, Corrected.getAsString()); 535 else 536 Diag(NameLoc, QualifiedDiag) 537 << Name << computeDeclContext(SS, false) << Corrected 538 << SS.getRange() 539 << FixItHint::CreateReplacement(NameLoc, Corrected.getAsString()); 540 541 // Update the name, so that the caller has the new name. 542 Name = Corrected.getAsIdentifierInfo(); 543 544 // Typo correction corrected to a keyword. 545 if (Result.empty()) 546 return Corrected.getAsIdentifierInfo(); 547 548 Diag(FirstDecl->getLocation(), diag::note_previous_decl) 549 << FirstDecl->getDeclName(); 550 551 // If we found an Objective-C instance variable, let 552 // LookupInObjCMethod build the appropriate expression to 553 // reference the ivar. 554 // FIXME: This is a gross hack. 555 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) { 556 Result.clear(); 557 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier())); 558 return move(E); 559 } 560 561 goto Corrected; 562 } 563 } 564 565 // We failed to correct; just fall through and let the parser deal with it. 566 Result.suppressDiagnostics(); 567 return NameClassification::Unknown(); 568 569 case LookupResult::NotFoundInCurrentInstantiation: 570 // We performed name lookup into the current instantiation, and there were 571 // dependent bases, so we treat this result the same way as any other 572 // dependent nested-name-specifier. 573 574 // C++ [temp.res]p2: 575 // A name used in a template declaration or definition and that is 576 // dependent on a template-parameter is assumed not to name a type 577 // unless the applicable name lookup finds a type name or the name is 578 // qualified by the keyword typename. 579 // 580 // FIXME: If the next token is '<', we might want to ask the parser to 581 // perform some heroics to see if we actually have a 582 // template-argument-list, which would indicate a missing 'template' 583 // keyword here. 584 return BuildDependentDeclRefExpr(SS, NameInfo, /*TemplateArgs=*/0); 585 586 case LookupResult::Found: 587 case LookupResult::FoundOverloaded: 588 case LookupResult::FoundUnresolvedValue: 589 break; 590 591 case LookupResult::Ambiguous: 592 if (getLangOptions().CPlusPlus && NextToken.is(tok::less) && 593 hasAnyAcceptableTemplateNames(Result)) { 594 // C++ [temp.local]p3: 595 // A lookup that finds an injected-class-name (10.2) can result in an 596 // ambiguity in certain cases (for example, if it is found in more than 597 // one base class). If all of the injected-class-names that are found 598 // refer to specializations of the same class template, and if the name 599 // is followed by a template-argument-list, the reference refers to the 600 // class template itself and not a specialization thereof, and is not 601 // ambiguous. 602 // 603 // This filtering can make an ambiguous result into an unambiguous one, 604 // so try again after filtering out template names. 605 FilterAcceptableTemplateNames(Result); 606 if (!Result.isAmbiguous()) { 607 IsFilteredTemplateName = true; 608 break; 609 } 610 } 611 612 // Diagnose the ambiguity and return an error. 613 return NameClassification::Error(); 614 } 615 616 if (getLangOptions().CPlusPlus && NextToken.is(tok::less) && 617 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) { 618 // C++ [temp.names]p3: 619 // After name lookup (3.4) finds that a name is a template-name or that 620 // an operator-function-id or a literal- operator-id refers to a set of 621 // overloaded functions any member of which is a function template if 622 // this is followed by a <, the < is always taken as the delimiter of a 623 // template-argument-list and never as the less-than operator. 624 if (!IsFilteredTemplateName) 625 FilterAcceptableTemplateNames(Result); 626 627 if (!Result.empty()) { 628 bool IsFunctionTemplate; 629 TemplateName Template; 630 if (Result.end() - Result.begin() > 1) { 631 IsFunctionTemplate = true; 632 Template = Context.getOverloadedTemplateName(Result.begin(), 633 Result.end()); 634 } else { 635 TemplateDecl *TD 636 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl()); 637 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD); 638 639 if (SS.isSet() && !SS.isInvalid()) 640 Template = Context.getQualifiedTemplateName(SS.getScopeRep(), 641 /*TemplateKeyword=*/false, 642 TD); 643 else 644 Template = TemplateName(TD); 645 } 646 647 if (IsFunctionTemplate) { 648 // Function templates always go through overload resolution, at which 649 // point we'll perform the various checks (e.g., accessibility) we need 650 // to based on which function we selected. 651 Result.suppressDiagnostics(); 652 653 return NameClassification::FunctionTemplate(Template); 654 } 655 656 return NameClassification::TypeTemplate(Template); 657 } 658 } 659 660 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl(); 661 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) { 662 DiagnoseUseOfDecl(Type, NameLoc); 663 QualType T = Context.getTypeDeclType(Type); 664 return ParsedType::make(T); 665 } 666 667 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl); 668 if (!Class) { 669 // FIXME: It's unfortunate that we don't have a Type node for handling this. 670 if (ObjCCompatibleAliasDecl *Alias 671 = dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl)) 672 Class = Alias->getClassInterface(); 673 } 674 675 if (Class) { 676 DiagnoseUseOfDecl(Class, NameLoc); 677 678 if (NextToken.is(tok::period)) { 679 // Interface. <something> is parsed as a property reference expression. 680 // Just return "unknown" as a fall-through for now. 681 Result.suppressDiagnostics(); 682 return NameClassification::Unknown(); 683 } 684 685 QualType T = Context.getObjCInterfaceType(Class); 686 return ParsedType::make(T); 687 } 688 689 if (!Result.empty() && (*Result.begin())->isCXXClassMember()) 690 return BuildPossibleImplicitMemberExpr(SS, Result, 0); 691 692 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren)); 693 return BuildDeclarationNameExpr(SS, Result, ADL); 694} 695 696// Determines the context to return to after temporarily entering a 697// context. This depends in an unnecessarily complicated way on the 698// exact ordering of callbacks from the parser. 699DeclContext *Sema::getContainingDC(DeclContext *DC) { 700 701 // Functions defined inline within classes aren't parsed until we've 702 // finished parsing the top-level class, so the top-level class is 703 // the context we'll need to return to. 704 if (isa<FunctionDecl>(DC)) { 705 DC = DC->getLexicalParent(); 706 707 // A function not defined within a class will always return to its 708 // lexical context. 709 if (!isa<CXXRecordDecl>(DC)) 710 return DC; 711 712 // A C++ inline method/friend is parsed *after* the topmost class 713 // it was declared in is fully parsed ("complete"); the topmost 714 // class is the context we need to return to. 715 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 716 DC = RD; 717 718 // Return the declaration context of the topmost class the inline method is 719 // declared in. 720 return DC; 721 } 722 723 // ObjCMethodDecls are parsed (for some reason) outside the context 724 // of the class. 725 if (isa<ObjCMethodDecl>(DC)) 726 return DC->getLexicalParent()->getLexicalParent(); 727 728 return DC->getLexicalParent(); 729} 730 731void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 732 assert(getContainingDC(DC) == CurContext && 733 "The next DeclContext should be lexically contained in the current one."); 734 CurContext = DC; 735 S->setEntity(DC); 736} 737 738void Sema::PopDeclContext() { 739 assert(CurContext && "DeclContext imbalance!"); 740 741 CurContext = getContainingDC(CurContext); 742 assert(CurContext && "Popped translation unit!"); 743} 744 745/// EnterDeclaratorContext - Used when we must lookup names in the context 746/// of a declarator's nested name specifier. 747/// 748void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 749 // C++0x [basic.lookup.unqual]p13: 750 // A name used in the definition of a static data member of class 751 // X (after the qualified-id of the static member) is looked up as 752 // if the name was used in a member function of X. 753 // C++0x [basic.lookup.unqual]p14: 754 // If a variable member of a namespace is defined outside of the 755 // scope of its namespace then any name used in the definition of 756 // the variable member (after the declarator-id) is looked up as 757 // if the definition of the variable member occurred in its 758 // namespace. 759 // Both of these imply that we should push a scope whose context 760 // is the semantic context of the declaration. We can't use 761 // PushDeclContext here because that context is not necessarily 762 // lexically contained in the current context. Fortunately, 763 // the containing scope should have the appropriate information. 764 765 assert(!S->getEntity() && "scope already has entity"); 766 767#ifndef NDEBUG 768 Scope *Ancestor = S->getParent(); 769 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 770 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 771#endif 772 773 CurContext = DC; 774 S->setEntity(DC); 775} 776 777void Sema::ExitDeclaratorContext(Scope *S) { 778 assert(S->getEntity() == CurContext && "Context imbalance!"); 779 780 // Switch back to the lexical context. The safety of this is 781 // enforced by an assert in EnterDeclaratorContext. 782 Scope *Ancestor = S->getParent(); 783 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 784 CurContext = (DeclContext*) Ancestor->getEntity(); 785 786 // We don't need to do anything with the scope, which is going to 787 // disappear. 788} 789 790/// \brief Determine whether we allow overloading of the function 791/// PrevDecl with another declaration. 792/// 793/// This routine determines whether overloading is possible, not 794/// whether some new function is actually an overload. It will return 795/// true in C++ (where we can always provide overloads) or, as an 796/// extension, in C when the previous function is already an 797/// overloaded function declaration or has the "overloadable" 798/// attribute. 799static bool AllowOverloadingOfFunction(LookupResult &Previous, 800 ASTContext &Context) { 801 if (Context.getLangOptions().CPlusPlus) 802 return true; 803 804 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 805 return true; 806 807 return (Previous.getResultKind() == LookupResult::Found 808 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 809} 810 811/// Add this decl to the scope shadowed decl chains. 812void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 813 // Move up the scope chain until we find the nearest enclosing 814 // non-transparent context. The declaration will be introduced into this 815 // scope. 816 while (S->getEntity() && 817 ((DeclContext *)S->getEntity())->isTransparentContext()) 818 S = S->getParent(); 819 820 // Add scoped declarations into their context, so that they can be 821 // found later. Declarations without a context won't be inserted 822 // into any context. 823 if (AddToContext) 824 CurContext->addDecl(D); 825 826 // Out-of-line definitions shouldn't be pushed into scope in C++. 827 // Out-of-line variable and function definitions shouldn't even in C. 828 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 829 D->isOutOfLine()) 830 return; 831 832 // Template instantiations should also not be pushed into scope. 833 if (isa<FunctionDecl>(D) && 834 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 835 return; 836 837 // If this replaces anything in the current scope, 838 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 839 IEnd = IdResolver.end(); 840 for (; I != IEnd; ++I) { 841 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 842 S->RemoveDecl(*I); 843 IdResolver.RemoveDecl(*I); 844 845 // Should only need to replace one decl. 846 break; 847 } 848 } 849 850 S->AddDecl(D); 851 852 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { 853 // Implicitly-generated labels may end up getting generated in an order that 854 // isn't strictly lexical, which breaks name lookup. Be careful to insert 855 // the label at the appropriate place in the identifier chain. 856 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { 857 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); 858 if (IDC == CurContext) { 859 if (!S->isDeclScope(*I)) 860 continue; 861 } else if (IDC->Encloses(CurContext)) 862 break; 863 } 864 865 IdResolver.InsertDeclAfter(I, D); 866 } else { 867 IdResolver.AddDecl(D); 868 } 869} 870 871bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, 872 bool ExplicitInstantiationOrSpecialization) { 873 return IdResolver.isDeclInScope(D, Ctx, Context, S, 874 ExplicitInstantiationOrSpecialization); 875} 876 877Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 878 DeclContext *TargetDC = DC->getPrimaryContext(); 879 do { 880 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 881 if (ScopeDC->getPrimaryContext() == TargetDC) 882 return S; 883 } while ((S = S->getParent())); 884 885 return 0; 886} 887 888static bool isOutOfScopePreviousDeclaration(NamedDecl *, 889 DeclContext*, 890 ASTContext&); 891 892/// Filters out lookup results that don't fall within the given scope 893/// as determined by isDeclInScope. 894void Sema::FilterLookupForScope(LookupResult &R, 895 DeclContext *Ctx, Scope *S, 896 bool ConsiderLinkage, 897 bool ExplicitInstantiationOrSpecialization) { 898 LookupResult::Filter F = R.makeFilter(); 899 while (F.hasNext()) { 900 NamedDecl *D = F.next(); 901 902 if (isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) 903 continue; 904 905 if (ConsiderLinkage && 906 isOutOfScopePreviousDeclaration(D, Ctx, Context)) 907 continue; 908 909 F.erase(); 910 } 911 912 F.done(); 913} 914 915static bool isUsingDecl(NamedDecl *D) { 916 return isa<UsingShadowDecl>(D) || 917 isa<UnresolvedUsingTypenameDecl>(D) || 918 isa<UnresolvedUsingValueDecl>(D); 919} 920 921/// Removes using shadow declarations from the lookup results. 922static void RemoveUsingDecls(LookupResult &R) { 923 LookupResult::Filter F = R.makeFilter(); 924 while (F.hasNext()) 925 if (isUsingDecl(F.next())) 926 F.erase(); 927 928 F.done(); 929} 930 931/// \brief Check for this common pattern: 932/// @code 933/// class S { 934/// S(const S&); // DO NOT IMPLEMENT 935/// void operator=(const S&); // DO NOT IMPLEMENT 936/// }; 937/// @endcode 938static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 939 // FIXME: Should check for private access too but access is set after we get 940 // the decl here. 941 if (D->doesThisDeclarationHaveABody()) 942 return false; 943 944 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 945 return CD->isCopyConstructor(); 946 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 947 return Method->isCopyAssignmentOperator(); 948 return false; 949} 950 951bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 952 assert(D); 953 954 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 955 return false; 956 957 // Ignore class templates. 958 if (D->getDeclContext()->isDependentContext() || 959 D->getLexicalDeclContext()->isDependentContext()) 960 return false; 961 962 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 963 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 964 return false; 965 966 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 967 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 968 return false; 969 } else { 970 // 'static inline' functions are used in headers; don't warn. 971 if (FD->getStorageClass() == SC_Static && 972 FD->isInlineSpecified()) 973 return false; 974 } 975 976 if (FD->doesThisDeclarationHaveABody() && 977 Context.DeclMustBeEmitted(FD)) 978 return false; 979 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 980 if (!VD->isFileVarDecl() || 981 VD->getType().isConstant(Context) || 982 Context.DeclMustBeEmitted(VD)) 983 return false; 984 985 if (VD->isStaticDataMember() && 986 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 987 return false; 988 989 } else { 990 return false; 991 } 992 993 // Only warn for unused decls internal to the translation unit. 994 if (D->getLinkage() == ExternalLinkage) 995 return false; 996 997 return true; 998} 999 1000void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 1001 if (!D) 1002 return; 1003 1004 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1005 const FunctionDecl *First = FD->getFirstDeclaration(); 1006 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 1007 return; // First should already be in the vector. 1008 } 1009 1010 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1011 const VarDecl *First = VD->getFirstDeclaration(); 1012 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 1013 return; // First should already be in the vector. 1014 } 1015 1016 if (ShouldWarnIfUnusedFileScopedDecl(D)) 1017 UnusedFileScopedDecls.push_back(D); 1018 } 1019 1020static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 1021 if (D->isInvalidDecl()) 1022 return false; 1023 1024 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 1025 return false; 1026 1027 if (isa<LabelDecl>(D)) 1028 return true; 1029 1030 // White-list anything that isn't a local variable. 1031 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 1032 !D->getDeclContext()->isFunctionOrMethod()) 1033 return false; 1034 1035 // Types of valid local variables should be complete, so this should succeed. 1036 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 1037 1038 // White-list anything with an __attribute__((unused)) type. 1039 QualType Ty = VD->getType(); 1040 1041 // Only look at the outermost level of typedef. 1042 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 1043 if (TT->getDecl()->hasAttr<UnusedAttr>()) 1044 return false; 1045 } 1046 1047 // If we failed to complete the type for some reason, or if the type is 1048 // dependent, don't diagnose the variable. 1049 if (Ty->isIncompleteType() || Ty->isDependentType()) 1050 return false; 1051 1052 if (const TagType *TT = Ty->getAs<TagType>()) { 1053 const TagDecl *Tag = TT->getDecl(); 1054 if (Tag->hasAttr<UnusedAttr>()) 1055 return false; 1056 1057 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 1058 // FIXME: Checking for the presence of a user-declared constructor 1059 // isn't completely accurate; we'd prefer to check that the initializer 1060 // has no side effects. 1061 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 1062 return false; 1063 } 1064 } 1065 1066 // TODO: __attribute__((unused)) templates? 1067 } 1068 1069 return true; 1070} 1071 1072/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 1073/// unless they are marked attr(unused). 1074void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 1075 if (!ShouldDiagnoseUnusedDecl(D)) 1076 return; 1077 1078 unsigned DiagID; 1079 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 1080 DiagID = diag::warn_unused_exception_param; 1081 else if (isa<LabelDecl>(D)) 1082 DiagID = diag::warn_unused_label; 1083 else 1084 DiagID = diag::warn_unused_variable; 1085 1086 Diag(D->getLocation(), DiagID) << D->getDeclName(); 1087} 1088 1089static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 1090 // Verify that we have no forward references left. If so, there was a goto 1091 // or address of a label taken, but no definition of it. Label fwd 1092 // definitions are indicated with a null substmt. 1093 if (L->getStmt() == 0) 1094 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 1095} 1096 1097void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 1098 if (S->decl_empty()) return; 1099 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 1100 "Scope shouldn't contain decls!"); 1101 1102 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 1103 I != E; ++I) { 1104 Decl *TmpD = (*I); 1105 assert(TmpD && "This decl didn't get pushed??"); 1106 1107 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 1108 NamedDecl *D = cast<NamedDecl>(TmpD); 1109 1110 if (!D->getDeclName()) continue; 1111 1112 // Diagnose unused variables in this scope. 1113 if (!S->hasErrorOccurred()) 1114 DiagnoseUnusedDecl(D); 1115 1116 // If this was a forward reference to a label, verify it was defined. 1117 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 1118 CheckPoppedLabel(LD, *this); 1119 1120 // Remove this name from our lexical scope. 1121 IdResolver.RemoveDecl(D); 1122 } 1123} 1124 1125/// \brief Look for an Objective-C class in the translation unit. 1126/// 1127/// \param Id The name of the Objective-C class we're looking for. If 1128/// typo-correction fixes this name, the Id will be updated 1129/// to the fixed name. 1130/// 1131/// \param IdLoc The location of the name in the translation unit. 1132/// 1133/// \param TypoCorrection If true, this routine will attempt typo correction 1134/// if there is no class with the given name. 1135/// 1136/// \returns The declaration of the named Objective-C class, or NULL if the 1137/// class could not be found. 1138ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 1139 SourceLocation IdLoc, 1140 bool TypoCorrection) { 1141 // The third "scope" argument is 0 since we aren't enabling lazy built-in 1142 // creation from this context. 1143 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 1144 1145 if (!IDecl && TypoCorrection) { 1146 // Perform typo correction at the given location, but only if we 1147 // find an Objective-C class name. 1148 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 1149 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 1150 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 1151 Diag(IdLoc, diag::err_undef_interface_suggest) 1152 << Id << IDecl->getDeclName() 1153 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 1154 Diag(IDecl->getLocation(), diag::note_previous_decl) 1155 << IDecl->getDeclName(); 1156 1157 Id = IDecl->getIdentifier(); 1158 } 1159 } 1160 1161 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 1162} 1163 1164/// getNonFieldDeclScope - Retrieves the innermost scope, starting 1165/// from S, where a non-field would be declared. This routine copes 1166/// with the difference between C and C++ scoping rules in structs and 1167/// unions. For example, the following code is well-formed in C but 1168/// ill-formed in C++: 1169/// @code 1170/// struct S6 { 1171/// enum { BAR } e; 1172/// }; 1173/// 1174/// void test_S6() { 1175/// struct S6 a; 1176/// a.e = BAR; 1177/// } 1178/// @endcode 1179/// For the declaration of BAR, this routine will return a different 1180/// scope. The scope S will be the scope of the unnamed enumeration 1181/// within S6. In C++, this routine will return the scope associated 1182/// with S6, because the enumeration's scope is a transparent 1183/// context but structures can contain non-field names. In C, this 1184/// routine will return the translation unit scope, since the 1185/// enumeration's scope is a transparent context and structures cannot 1186/// contain non-field names. 1187Scope *Sema::getNonFieldDeclScope(Scope *S) { 1188 while (((S->getFlags() & Scope::DeclScope) == 0) || 1189 (S->getEntity() && 1190 ((DeclContext *)S->getEntity())->isTransparentContext()) || 1191 (S->isClassScope() && !getLangOptions().CPlusPlus)) 1192 S = S->getParent(); 1193 return S; 1194} 1195 1196/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 1197/// file scope. lazily create a decl for it. ForRedeclaration is true 1198/// if we're creating this built-in in anticipation of redeclaring the 1199/// built-in. 1200NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 1201 Scope *S, bool ForRedeclaration, 1202 SourceLocation Loc) { 1203 Builtin::ID BID = (Builtin::ID)bid; 1204 1205 ASTContext::GetBuiltinTypeError Error; 1206 QualType R = Context.GetBuiltinType(BID, Error); 1207 switch (Error) { 1208 case ASTContext::GE_None: 1209 // Okay 1210 break; 1211 1212 case ASTContext::GE_Missing_stdio: 1213 if (ForRedeclaration) 1214 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 1215 << Context.BuiltinInfo.GetName(BID); 1216 return 0; 1217 1218 case ASTContext::GE_Missing_setjmp: 1219 if (ForRedeclaration) 1220 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 1221 << Context.BuiltinInfo.GetName(BID); 1222 return 0; 1223 } 1224 1225 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 1226 Diag(Loc, diag::ext_implicit_lib_function_decl) 1227 << Context.BuiltinInfo.GetName(BID) 1228 << R; 1229 if (Context.BuiltinInfo.getHeaderName(BID) && 1230 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 1231 != Diagnostic::Ignored) 1232 Diag(Loc, diag::note_please_include_header) 1233 << Context.BuiltinInfo.getHeaderName(BID) 1234 << Context.BuiltinInfo.GetName(BID); 1235 } 1236 1237 FunctionDecl *New = FunctionDecl::Create(Context, 1238 Context.getTranslationUnitDecl(), 1239 Loc, Loc, II, R, /*TInfo=*/0, 1240 SC_Extern, 1241 SC_None, false, 1242 /*hasPrototype=*/true); 1243 New->setImplicit(); 1244 1245 // Create Decl objects for each parameter, adding them to the 1246 // FunctionDecl. 1247 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 1248 llvm::SmallVector<ParmVarDecl*, 16> Params; 1249 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) { 1250 ParmVarDecl *parm = 1251 ParmVarDecl::Create(Context, New, SourceLocation(), 1252 SourceLocation(), 0, 1253 FT->getArgType(i), /*TInfo=*/0, 1254 SC_None, SC_None, 0); 1255 parm->setScopeInfo(0, i); 1256 Params.push_back(parm); 1257 } 1258 New->setParams(Params.data(), Params.size()); 1259 } 1260 1261 AddKnownFunctionAttributes(New); 1262 1263 // TUScope is the translation-unit scope to insert this function into. 1264 // FIXME: This is hideous. We need to teach PushOnScopeChains to 1265 // relate Scopes to DeclContexts, and probably eliminate CurContext 1266 // entirely, but we're not there yet. 1267 DeclContext *SavedContext = CurContext; 1268 CurContext = Context.getTranslationUnitDecl(); 1269 PushOnScopeChains(New, TUScope); 1270 CurContext = SavedContext; 1271 return New; 1272} 1273 1274/// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the 1275/// same name and scope as a previous declaration 'Old'. Figure out 1276/// how to resolve this situation, merging decls or emitting 1277/// diagnostics as appropriate. If there was an error, set New to be invalid. 1278/// 1279void Sema::MergeTypedefNameDecl(TypedefNameDecl *New, LookupResult &OldDecls) { 1280 // If the new decl is known invalid already, don't bother doing any 1281 // merging checks. 1282 if (New->isInvalidDecl()) return; 1283 1284 // Allow multiple definitions for ObjC built-in typedefs. 1285 // FIXME: Verify the underlying types are equivalent! 1286 if (getLangOptions().ObjC1) { 1287 const IdentifierInfo *TypeID = New->getIdentifier(); 1288 switch (TypeID->getLength()) { 1289 default: break; 1290 case 2: 1291 if (!TypeID->isStr("id")) 1292 break; 1293 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 1294 // Install the built-in type for 'id', ignoring the current definition. 1295 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 1296 return; 1297 case 5: 1298 if (!TypeID->isStr("Class")) 1299 break; 1300 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 1301 // Install the built-in type for 'Class', ignoring the current definition. 1302 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 1303 return; 1304 case 3: 1305 if (!TypeID->isStr("SEL")) 1306 break; 1307 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 1308 // Install the built-in type for 'SEL', ignoring the current definition. 1309 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 1310 return; 1311 case 8: 1312 if (!TypeID->isStr("Protocol")) 1313 break; 1314 Context.setObjCProtoType(New->getUnderlyingType()); 1315 return; 1316 } 1317 // Fall through - the typedef name was not a builtin type. 1318 } 1319 1320 // Verify the old decl was also a type. 1321 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 1322 if (!Old) { 1323 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1324 << New->getDeclName(); 1325 1326 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 1327 if (OldD->getLocation().isValid()) 1328 Diag(OldD->getLocation(), diag::note_previous_definition); 1329 1330 return New->setInvalidDecl(); 1331 } 1332 1333 // If the old declaration is invalid, just give up here. 1334 if (Old->isInvalidDecl()) 1335 return New->setInvalidDecl(); 1336 1337 // Determine the "old" type we'll use for checking and diagnostics. 1338 QualType OldType; 1339 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old)) 1340 OldType = OldTypedef->getUnderlyingType(); 1341 else 1342 OldType = Context.getTypeDeclType(Old); 1343 1344 // If the typedef types are not identical, reject them in all languages and 1345 // with any extensions enabled. 1346 1347 if (OldType != New->getUnderlyingType() && 1348 Context.getCanonicalType(OldType) != 1349 Context.getCanonicalType(New->getUnderlyingType())) { 1350 int Kind = 0; 1351 if (isa<TypeAliasDecl>(Old)) 1352 Kind = 1; 1353 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 1354 << Kind << New->getUnderlyingType() << OldType; 1355 if (Old->getLocation().isValid()) 1356 Diag(Old->getLocation(), diag::note_previous_definition); 1357 return New->setInvalidDecl(); 1358 } 1359 1360 // The types match. Link up the redeclaration chain if the old 1361 // declaration was a typedef. 1362 // FIXME: this is a potential source of wierdness if the type 1363 // spellings don't match exactly. 1364 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) 1365 New->setPreviousDeclaration(Typedef); 1366 1367 if (getLangOptions().Microsoft) 1368 return; 1369 1370 if (getLangOptions().CPlusPlus) { 1371 // C++ [dcl.typedef]p2: 1372 // In a given non-class scope, a typedef specifier can be used to 1373 // redefine the name of any type declared in that scope to refer 1374 // to the type to which it already refers. 1375 if (!isa<CXXRecordDecl>(CurContext)) 1376 return; 1377 1378 // C++0x [dcl.typedef]p4: 1379 // In a given class scope, a typedef specifier can be used to redefine 1380 // any class-name declared in that scope that is not also a typedef-name 1381 // to refer to the type to which it already refers. 1382 // 1383 // This wording came in via DR424, which was a correction to the 1384 // wording in DR56, which accidentally banned code like: 1385 // 1386 // struct S { 1387 // typedef struct A { } A; 1388 // }; 1389 // 1390 // in the C++03 standard. We implement the C++0x semantics, which 1391 // allow the above but disallow 1392 // 1393 // struct S { 1394 // typedef int I; 1395 // typedef int I; 1396 // }; 1397 // 1398 // since that was the intent of DR56. 1399 if (!isa<TypedefNameDecl>(Old)) 1400 return; 1401 1402 Diag(New->getLocation(), diag::err_redefinition) 1403 << New->getDeclName(); 1404 Diag(Old->getLocation(), diag::note_previous_definition); 1405 return New->setInvalidDecl(); 1406 } 1407 1408 // If we have a redefinition of a typedef in C, emit a warning. This warning 1409 // is normally mapped to an error, but can be controlled with 1410 // -Wtypedef-redefinition. If either the original or the redefinition is 1411 // in a system header, don't emit this for compatibility with GCC. 1412 if (getDiagnostics().getSuppressSystemWarnings() && 1413 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1414 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1415 return; 1416 1417 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1418 << New->getDeclName(); 1419 Diag(Old->getLocation(), diag::note_previous_definition); 1420 return; 1421} 1422 1423/// DeclhasAttr - returns true if decl Declaration already has the target 1424/// attribute. 1425static bool 1426DeclHasAttr(const Decl *D, const Attr *A) { 1427 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1428 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1429 if ((*i)->getKind() == A->getKind()) { 1430 // FIXME: Don't hardcode this check 1431 if (OA && isa<OwnershipAttr>(*i)) 1432 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1433 return true; 1434 } 1435 1436 return false; 1437} 1438 1439/// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 1440static void mergeDeclAttributes(Decl *newDecl, const Decl *oldDecl, 1441 ASTContext &C) { 1442 if (!oldDecl->hasAttrs()) 1443 return; 1444 1445 bool foundAny = newDecl->hasAttrs(); 1446 1447 // Ensure that any moving of objects within the allocated map is done before 1448 // we process them. 1449 if (!foundAny) newDecl->setAttrs(AttrVec()); 1450 1451 for (specific_attr_iterator<InheritableAttr> 1452 i = oldDecl->specific_attr_begin<InheritableAttr>(), 1453 e = oldDecl->specific_attr_end<InheritableAttr>(); i != e; ++i) { 1454 if (!DeclHasAttr(newDecl, *i)) { 1455 InheritableAttr *newAttr = cast<InheritableAttr>((*i)->clone(C)); 1456 newAttr->setInherited(true); 1457 newDecl->addAttr(newAttr); 1458 foundAny = true; 1459 } 1460 } 1461 1462 if (!foundAny) newDecl->dropAttrs(); 1463} 1464 1465/// mergeParamDeclAttributes - Copy attributes from the old parameter 1466/// to the new one. 1467static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 1468 const ParmVarDecl *oldDecl, 1469 ASTContext &C) { 1470 if (!oldDecl->hasAttrs()) 1471 return; 1472 1473 bool foundAny = newDecl->hasAttrs(); 1474 1475 // Ensure that any moving of objects within the allocated map is 1476 // done before we process them. 1477 if (!foundAny) newDecl->setAttrs(AttrVec()); 1478 1479 for (specific_attr_iterator<InheritableParamAttr> 1480 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 1481 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 1482 if (!DeclHasAttr(newDecl, *i)) { 1483 InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(C)); 1484 newAttr->setInherited(true); 1485 newDecl->addAttr(newAttr); 1486 foundAny = true; 1487 } 1488 } 1489 1490 if (!foundAny) newDecl->dropAttrs(); 1491} 1492 1493namespace { 1494 1495/// Used in MergeFunctionDecl to keep track of function parameters in 1496/// C. 1497struct GNUCompatibleParamWarning { 1498 ParmVarDecl *OldParm; 1499 ParmVarDecl *NewParm; 1500 QualType PromotedType; 1501}; 1502 1503} 1504 1505/// getSpecialMember - get the special member enum for a method. 1506Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1507 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1508 if (Ctor->isCopyConstructor()) 1509 return Sema::CXXCopyConstructor; 1510 1511 if (Ctor->isDefaultConstructor()) 1512 return Sema::CXXDefaultConstructor; 1513 } 1514 1515 if (isa<CXXDestructorDecl>(MD)) 1516 return Sema::CXXDestructor; 1517 1518 if (MD->isCopyAssignmentOperator()) 1519 return Sema::CXXCopyAssignment; 1520 1521 return Sema::CXXInvalid; 1522} 1523 1524/// canRedefineFunction - checks if a function can be redefined. Currently, 1525/// only extern inline functions can be redefined, and even then only in 1526/// GNU89 mode. 1527static bool canRedefineFunction(const FunctionDecl *FD, 1528 const LangOptions& LangOpts) { 1529 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1530 FD->isInlineSpecified() && 1531 FD->getStorageClass() == SC_Extern); 1532} 1533 1534/// MergeFunctionDecl - We just parsed a function 'New' from 1535/// declarator D which has the same name and scope as a previous 1536/// declaration 'Old'. Figure out how to resolve this situation, 1537/// merging decls or emitting diagnostics as appropriate. 1538/// 1539/// In C++, New and Old must be declarations that are not 1540/// overloaded. Use IsOverload to determine whether New and Old are 1541/// overloaded, and to select the Old declaration that New should be 1542/// merged with. 1543/// 1544/// Returns true if there was an error, false otherwise. 1545bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1546 // Verify the old decl was also a function. 1547 FunctionDecl *Old = 0; 1548 if (FunctionTemplateDecl *OldFunctionTemplate 1549 = dyn_cast<FunctionTemplateDecl>(OldD)) 1550 Old = OldFunctionTemplate->getTemplatedDecl(); 1551 else 1552 Old = dyn_cast<FunctionDecl>(OldD); 1553 if (!Old) { 1554 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1555 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1556 Diag(Shadow->getTargetDecl()->getLocation(), 1557 diag::note_using_decl_target); 1558 Diag(Shadow->getUsingDecl()->getLocation(), 1559 diag::note_using_decl) << 0; 1560 return true; 1561 } 1562 1563 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1564 << New->getDeclName(); 1565 Diag(OldD->getLocation(), diag::note_previous_definition); 1566 return true; 1567 } 1568 1569 // Determine whether the previous declaration was a definition, 1570 // implicit declaration, or a declaration. 1571 diag::kind PrevDiag; 1572 if (Old->isThisDeclarationADefinition()) 1573 PrevDiag = diag::note_previous_definition; 1574 else if (Old->isImplicit()) 1575 PrevDiag = diag::note_previous_implicit_declaration; 1576 else 1577 PrevDiag = diag::note_previous_declaration; 1578 1579 QualType OldQType = Context.getCanonicalType(Old->getType()); 1580 QualType NewQType = Context.getCanonicalType(New->getType()); 1581 1582 // Don't complain about this if we're in GNU89 mode and the old function 1583 // is an extern inline function. 1584 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1585 New->getStorageClass() == SC_Static && 1586 Old->getStorageClass() != SC_Static && 1587 !canRedefineFunction(Old, getLangOptions())) { 1588 if (getLangOptions().Microsoft) { 1589 Diag(New->getLocation(), diag::warn_static_non_static) << New; 1590 Diag(Old->getLocation(), PrevDiag); 1591 } else { 1592 Diag(New->getLocation(), diag::err_static_non_static) << New; 1593 Diag(Old->getLocation(), PrevDiag); 1594 return true; 1595 } 1596 } 1597 1598 // If a function is first declared with a calling convention, but is 1599 // later declared or defined without one, the second decl assumes the 1600 // calling convention of the first. 1601 // 1602 // For the new decl, we have to look at the NON-canonical type to tell the 1603 // difference between a function that really doesn't have a calling 1604 // convention and one that is declared cdecl. That's because in 1605 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1606 // because it is the default calling convention. 1607 // 1608 // Note also that we DO NOT return at this point, because we still have 1609 // other tests to run. 1610 const FunctionType *OldType = cast<FunctionType>(OldQType); 1611 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1612 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1613 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1614 bool RequiresAdjustment = false; 1615 if (OldTypeInfo.getCC() != CC_Default && 1616 NewTypeInfo.getCC() == CC_Default) { 1617 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1618 RequiresAdjustment = true; 1619 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1620 NewTypeInfo.getCC())) { 1621 // Calling conventions really aren't compatible, so complain. 1622 Diag(New->getLocation(), diag::err_cconv_change) 1623 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1624 << (OldTypeInfo.getCC() == CC_Default) 1625 << (OldTypeInfo.getCC() == CC_Default ? "" : 1626 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1627 Diag(Old->getLocation(), diag::note_previous_declaration); 1628 return true; 1629 } 1630 1631 // FIXME: diagnose the other way around? 1632 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1633 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1634 RequiresAdjustment = true; 1635 } 1636 1637 // Merge regparm attribute. 1638 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || 1639 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1640 if (NewTypeInfo.getHasRegParm()) { 1641 Diag(New->getLocation(), diag::err_regparm_mismatch) 1642 << NewType->getRegParmType() 1643 << OldType->getRegParmType(); 1644 Diag(Old->getLocation(), diag::note_previous_declaration); 1645 return true; 1646 } 1647 1648 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1649 RequiresAdjustment = true; 1650 } 1651 1652 if (RequiresAdjustment) { 1653 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1654 New->setType(QualType(NewType, 0)); 1655 NewQType = Context.getCanonicalType(New->getType()); 1656 } 1657 1658 if (getLangOptions().CPlusPlus) { 1659 // (C++98 13.1p2): 1660 // Certain function declarations cannot be overloaded: 1661 // -- Function declarations that differ only in the return type 1662 // cannot be overloaded. 1663 QualType OldReturnType = OldType->getResultType(); 1664 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1665 QualType ResQT; 1666 if (OldReturnType != NewReturnType) { 1667 if (NewReturnType->isObjCObjectPointerType() 1668 && OldReturnType->isObjCObjectPointerType()) 1669 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1670 if (ResQT.isNull()) { 1671 if (New->isCXXClassMember() && New->isOutOfLine()) 1672 Diag(New->getLocation(), 1673 diag::err_member_def_does_not_match_ret_type) << New; 1674 else 1675 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1676 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1677 return true; 1678 } 1679 else 1680 NewQType = ResQT; 1681 } 1682 1683 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1684 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1685 if (OldMethod && NewMethod) { 1686 // Preserve triviality. 1687 NewMethod->setTrivial(OldMethod->isTrivial()); 1688 1689 bool isFriend = NewMethod->getFriendObjectKind(); 1690 1691 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1692 // -- Member function declarations with the same name and the 1693 // same parameter types cannot be overloaded if any of them 1694 // is a static member function declaration. 1695 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1696 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1697 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1698 return true; 1699 } 1700 1701 // C++ [class.mem]p1: 1702 // [...] A member shall not be declared twice in the 1703 // member-specification, except that a nested class or member 1704 // class template can be declared and then later defined. 1705 unsigned NewDiag; 1706 if (isa<CXXConstructorDecl>(OldMethod)) 1707 NewDiag = diag::err_constructor_redeclared; 1708 else if (isa<CXXDestructorDecl>(NewMethod)) 1709 NewDiag = diag::err_destructor_redeclared; 1710 else if (isa<CXXConversionDecl>(NewMethod)) 1711 NewDiag = diag::err_conv_function_redeclared; 1712 else 1713 NewDiag = diag::err_member_redeclared; 1714 1715 Diag(New->getLocation(), NewDiag); 1716 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1717 1718 // Complain if this is an explicit declaration of a special 1719 // member that was initially declared implicitly. 1720 // 1721 // As an exception, it's okay to befriend such methods in order 1722 // to permit the implicit constructor/destructor/operator calls. 1723 } else if (OldMethod->isImplicit()) { 1724 if (isFriend) { 1725 NewMethod->setImplicit(); 1726 } else { 1727 Diag(NewMethod->getLocation(), 1728 diag::err_definition_of_implicitly_declared_member) 1729 << New << getSpecialMember(OldMethod); 1730 return true; 1731 } 1732 } else if (OldMethod->isExplicitlyDefaulted()) { 1733 Diag(NewMethod->getLocation(), 1734 diag::err_definition_of_explicitly_defaulted_member) 1735 << getSpecialMember(OldMethod); 1736 return true; 1737 } 1738 } 1739 1740 // (C++98 8.3.5p3): 1741 // All declarations for a function shall agree exactly in both the 1742 // return type and the parameter-type-list. 1743 // We also want to respect all the extended bits except noreturn. 1744 1745 // noreturn should now match unless the old type info didn't have it. 1746 QualType OldQTypeForComparison = OldQType; 1747 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1748 assert(OldQType == QualType(OldType, 0)); 1749 const FunctionType *OldTypeForComparison 1750 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1751 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1752 assert(OldQTypeForComparison.isCanonical()); 1753 } 1754 1755 if (OldQTypeForComparison == NewQType) 1756 return MergeCompatibleFunctionDecls(New, Old); 1757 1758 // Fall through for conflicting redeclarations and redefinitions. 1759 } 1760 1761 // C: Function types need to be compatible, not identical. This handles 1762 // duplicate function decls like "void f(int); void f(enum X);" properly. 1763 if (!getLangOptions().CPlusPlus && 1764 Context.typesAreCompatible(OldQType, NewQType)) { 1765 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1766 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1767 const FunctionProtoType *OldProto = 0; 1768 if (isa<FunctionNoProtoType>(NewFuncType) && 1769 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1770 // The old declaration provided a function prototype, but the 1771 // new declaration does not. Merge in the prototype. 1772 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1773 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1774 OldProto->arg_type_end()); 1775 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1776 ParamTypes.data(), ParamTypes.size(), 1777 OldProto->getExtProtoInfo()); 1778 New->setType(NewQType); 1779 New->setHasInheritedPrototype(); 1780 1781 // Synthesize a parameter for each argument type. 1782 llvm::SmallVector<ParmVarDecl*, 16> Params; 1783 for (FunctionProtoType::arg_type_iterator 1784 ParamType = OldProto->arg_type_begin(), 1785 ParamEnd = OldProto->arg_type_end(); 1786 ParamType != ParamEnd; ++ParamType) { 1787 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1788 SourceLocation(), 1789 SourceLocation(), 0, 1790 *ParamType, /*TInfo=*/0, 1791 SC_None, SC_None, 1792 0); 1793 Param->setScopeInfo(0, Params.size()); 1794 Param->setImplicit(); 1795 Params.push_back(Param); 1796 } 1797 1798 New->setParams(Params.data(), Params.size()); 1799 } 1800 1801 return MergeCompatibleFunctionDecls(New, Old); 1802 } 1803 1804 // GNU C permits a K&R definition to follow a prototype declaration 1805 // if the declared types of the parameters in the K&R definition 1806 // match the types in the prototype declaration, even when the 1807 // promoted types of the parameters from the K&R definition differ 1808 // from the types in the prototype. GCC then keeps the types from 1809 // the prototype. 1810 // 1811 // If a variadic prototype is followed by a non-variadic K&R definition, 1812 // the K&R definition becomes variadic. This is sort of an edge case, but 1813 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1814 // C99 6.9.1p8. 1815 if (!getLangOptions().CPlusPlus && 1816 Old->hasPrototype() && !New->hasPrototype() && 1817 New->getType()->getAs<FunctionProtoType>() && 1818 Old->getNumParams() == New->getNumParams()) { 1819 llvm::SmallVector<QualType, 16> ArgTypes; 1820 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1821 const FunctionProtoType *OldProto 1822 = Old->getType()->getAs<FunctionProtoType>(); 1823 const FunctionProtoType *NewProto 1824 = New->getType()->getAs<FunctionProtoType>(); 1825 1826 // Determine whether this is the GNU C extension. 1827 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1828 NewProto->getResultType()); 1829 bool LooseCompatible = !MergedReturn.isNull(); 1830 for (unsigned Idx = 0, End = Old->getNumParams(); 1831 LooseCompatible && Idx != End; ++Idx) { 1832 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1833 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1834 if (Context.typesAreCompatible(OldParm->getType(), 1835 NewProto->getArgType(Idx))) { 1836 ArgTypes.push_back(NewParm->getType()); 1837 } else if (Context.typesAreCompatible(OldParm->getType(), 1838 NewParm->getType(), 1839 /*CompareUnqualified=*/true)) { 1840 GNUCompatibleParamWarning Warn 1841 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1842 Warnings.push_back(Warn); 1843 ArgTypes.push_back(NewParm->getType()); 1844 } else 1845 LooseCompatible = false; 1846 } 1847 1848 if (LooseCompatible) { 1849 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1850 Diag(Warnings[Warn].NewParm->getLocation(), 1851 diag::ext_param_promoted_not_compatible_with_prototype) 1852 << Warnings[Warn].PromotedType 1853 << Warnings[Warn].OldParm->getType(); 1854 if (Warnings[Warn].OldParm->getLocation().isValid()) 1855 Diag(Warnings[Warn].OldParm->getLocation(), 1856 diag::note_previous_declaration); 1857 } 1858 1859 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1860 ArgTypes.size(), 1861 OldProto->getExtProtoInfo())); 1862 return MergeCompatibleFunctionDecls(New, Old); 1863 } 1864 1865 // Fall through to diagnose conflicting types. 1866 } 1867 1868 // A function that has already been declared has been redeclared or defined 1869 // with a different type- show appropriate diagnostic 1870 if (unsigned BuiltinID = Old->getBuiltinID()) { 1871 // The user has declared a builtin function with an incompatible 1872 // signature. 1873 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1874 // The function the user is redeclaring is a library-defined 1875 // function like 'malloc' or 'printf'. Warn about the 1876 // redeclaration, then pretend that we don't know about this 1877 // library built-in. 1878 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1879 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1880 << Old << Old->getType(); 1881 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1882 Old->setInvalidDecl(); 1883 return false; 1884 } 1885 1886 PrevDiag = diag::note_previous_builtin_declaration; 1887 } 1888 1889 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1890 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1891 return true; 1892} 1893 1894/// \brief Completes the merge of two function declarations that are 1895/// known to be compatible. 1896/// 1897/// This routine handles the merging of attributes and other 1898/// properties of function declarations form the old declaration to 1899/// the new declaration, once we know that New is in fact a 1900/// redeclaration of Old. 1901/// 1902/// \returns false 1903bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1904 // Merge the attributes 1905 mergeDeclAttributes(New, Old, Context); 1906 1907 // Merge the storage class. 1908 if (Old->getStorageClass() != SC_Extern && 1909 Old->getStorageClass() != SC_None) 1910 New->setStorageClass(Old->getStorageClass()); 1911 1912 // Merge "pure" flag. 1913 if (Old->isPure()) 1914 New->setPure(); 1915 1916 // Merge attributes from the parameters. These can mismatch with K&R 1917 // declarations. 1918 if (New->getNumParams() == Old->getNumParams()) 1919 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1920 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1921 Context); 1922 1923 if (getLangOptions().CPlusPlus) 1924 return MergeCXXFunctionDecl(New, Old); 1925 1926 return false; 1927} 1928 1929void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1930 const ObjCMethodDecl *oldMethod) { 1931 // Merge the attributes. 1932 mergeDeclAttributes(newMethod, oldMethod, Context); 1933 1934 // Merge attributes from the parameters. 1935 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1936 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1937 ni != ne; ++ni, ++oi) 1938 mergeParamDeclAttributes(*ni, *oi, Context); 1939} 1940 1941/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 1942/// scope as a previous declaration 'Old'. Figure out how to merge their types, 1943/// emitting diagnostics as appropriate. 1944/// 1945/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1946/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1947/// check them before the initializer is attached. 1948/// 1949void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1950 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1951 return; 1952 1953 QualType MergedT; 1954 if (getLangOptions().CPlusPlus) { 1955 AutoType *AT = New->getType()->getContainedAutoType(); 1956 if (AT && !AT->isDeduced()) { 1957 // We don't know what the new type is until the initializer is attached. 1958 return; 1959 } else if (Context.hasSameType(New->getType(), Old->getType())) { 1960 // These could still be something that needs exception specs checked. 1961 return MergeVarDeclExceptionSpecs(New, Old); 1962 } 1963 // C++ [basic.link]p10: 1964 // [...] the types specified by all declarations referring to a given 1965 // object or function shall be identical, except that declarations for an 1966 // array object can specify array types that differ by the presence or 1967 // absence of a major array bound (8.3.4). 1968 else if (Old->getType()->isIncompleteArrayType() && 1969 New->getType()->isArrayType()) { 1970 CanQual<ArrayType> OldArray 1971 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1972 CanQual<ArrayType> NewArray 1973 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1974 if (OldArray->getElementType() == NewArray->getElementType()) 1975 MergedT = New->getType(); 1976 } else if (Old->getType()->isArrayType() && 1977 New->getType()->isIncompleteArrayType()) { 1978 CanQual<ArrayType> OldArray 1979 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1980 CanQual<ArrayType> NewArray 1981 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1982 if (OldArray->getElementType() == NewArray->getElementType()) 1983 MergedT = Old->getType(); 1984 } else if (New->getType()->isObjCObjectPointerType() 1985 && Old->getType()->isObjCObjectPointerType()) { 1986 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1987 Old->getType()); 1988 } 1989 } else { 1990 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1991 } 1992 if (MergedT.isNull()) { 1993 Diag(New->getLocation(), diag::err_redefinition_different_type) 1994 << New->getDeclName(); 1995 Diag(Old->getLocation(), diag::note_previous_definition); 1996 return New->setInvalidDecl(); 1997 } 1998 New->setType(MergedT); 1999} 2000 2001/// MergeVarDecl - We just parsed a variable 'New' which has the same name 2002/// and scope as a previous declaration 'Old'. Figure out how to resolve this 2003/// situation, merging decls or emitting diagnostics as appropriate. 2004/// 2005/// Tentative definition rules (C99 6.9.2p2) are checked by 2006/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 2007/// definitions here, since the initializer hasn't been attached. 2008/// 2009void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 2010 // If the new decl is already invalid, don't do any other checking. 2011 if (New->isInvalidDecl()) 2012 return; 2013 2014 // Verify the old decl was also a variable. 2015 VarDecl *Old = 0; 2016 if (!Previous.isSingleResult() || 2017 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 2018 Diag(New->getLocation(), diag::err_redefinition_different_kind) 2019 << New->getDeclName(); 2020 Diag(Previous.getRepresentativeDecl()->getLocation(), 2021 diag::note_previous_definition); 2022 return New->setInvalidDecl(); 2023 } 2024 2025 // C++ [class.mem]p1: 2026 // A member shall not be declared twice in the member-specification [...] 2027 // 2028 // Here, we need only consider static data members. 2029 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 2030 Diag(New->getLocation(), diag::err_duplicate_member) 2031 << New->getIdentifier(); 2032 Diag(Old->getLocation(), diag::note_previous_declaration); 2033 New->setInvalidDecl(); 2034 } 2035 2036 mergeDeclAttributes(New, Old, Context); 2037 2038 // Merge the types. 2039 MergeVarDeclTypes(New, Old); 2040 if (New->isInvalidDecl()) 2041 return; 2042 2043 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 2044 if (New->getStorageClass() == SC_Static && 2045 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 2046 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 2047 Diag(Old->getLocation(), diag::note_previous_definition); 2048 return New->setInvalidDecl(); 2049 } 2050 // C99 6.2.2p4: 2051 // For an identifier declared with the storage-class specifier 2052 // extern in a scope in which a prior declaration of that 2053 // identifier is visible,23) if the prior declaration specifies 2054 // internal or external linkage, the linkage of the identifier at 2055 // the later declaration is the same as the linkage specified at 2056 // the prior declaration. If no prior declaration is visible, or 2057 // if the prior declaration specifies no linkage, then the 2058 // identifier has external linkage. 2059 if (New->hasExternalStorage() && Old->hasLinkage()) 2060 /* Okay */; 2061 else if (New->getStorageClass() != SC_Static && 2062 Old->getStorageClass() == SC_Static) { 2063 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 2064 Diag(Old->getLocation(), diag::note_previous_definition); 2065 return New->setInvalidDecl(); 2066 } 2067 2068 // Check if extern is followed by non-extern and vice-versa. 2069 if (New->hasExternalStorage() && 2070 !Old->hasLinkage() && Old->isLocalVarDecl()) { 2071 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 2072 Diag(Old->getLocation(), diag::note_previous_definition); 2073 return New->setInvalidDecl(); 2074 } 2075 if (Old->hasExternalStorage() && 2076 !New->hasLinkage() && New->isLocalVarDecl()) { 2077 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 2078 Diag(Old->getLocation(), diag::note_previous_definition); 2079 return New->setInvalidDecl(); 2080 } 2081 2082 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 2083 2084 // FIXME: The test for external storage here seems wrong? We still 2085 // need to check for mismatches. 2086 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 2087 // Don't complain about out-of-line definitions of static members. 2088 !(Old->getLexicalDeclContext()->isRecord() && 2089 !New->getLexicalDeclContext()->isRecord())) { 2090 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 2091 Diag(Old->getLocation(), diag::note_previous_definition); 2092 return New->setInvalidDecl(); 2093 } 2094 2095 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 2096 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 2097 Diag(Old->getLocation(), diag::note_previous_definition); 2098 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 2099 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 2100 Diag(Old->getLocation(), diag::note_previous_definition); 2101 } 2102 2103 // C++ doesn't have tentative definitions, so go right ahead and check here. 2104 const VarDecl *Def; 2105 if (getLangOptions().CPlusPlus && 2106 New->isThisDeclarationADefinition() == VarDecl::Definition && 2107 (Def = Old->getDefinition())) { 2108 Diag(New->getLocation(), diag::err_redefinition) 2109 << New->getDeclName(); 2110 Diag(Def->getLocation(), diag::note_previous_definition); 2111 New->setInvalidDecl(); 2112 return; 2113 } 2114 // c99 6.2.2 P4. 2115 // For an identifier declared with the storage-class specifier extern in a 2116 // scope in which a prior declaration of that identifier is visible, if 2117 // the prior declaration specifies internal or external linkage, the linkage 2118 // of the identifier at the later declaration is the same as the linkage 2119 // specified at the prior declaration. 2120 // FIXME. revisit this code. 2121 if (New->hasExternalStorage() && 2122 Old->getLinkage() == InternalLinkage && 2123 New->getDeclContext() == Old->getDeclContext()) 2124 New->setStorageClass(Old->getStorageClass()); 2125 2126 // Keep a chain of previous declarations. 2127 New->setPreviousDeclaration(Old); 2128 2129 // Inherit access appropriately. 2130 New->setAccess(Old->getAccess()); 2131} 2132 2133/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 2134/// no declarator (e.g. "struct foo;") is parsed. 2135Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 2136 DeclSpec &DS) { 2137 return ParsedFreeStandingDeclSpec(S, AS, DS, 2138 MultiTemplateParamsArg(*this, 0, 0)); 2139} 2140 2141/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 2142/// no declarator (e.g. "struct foo;") is parsed. It also accopts template 2143/// parameters to cope with template friend declarations. 2144Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 2145 DeclSpec &DS, 2146 MultiTemplateParamsArg TemplateParams) { 2147 Decl *TagD = 0; 2148 TagDecl *Tag = 0; 2149 if (DS.getTypeSpecType() == DeclSpec::TST_class || 2150 DS.getTypeSpecType() == DeclSpec::TST_struct || 2151 DS.getTypeSpecType() == DeclSpec::TST_union || 2152 DS.getTypeSpecType() == DeclSpec::TST_enum) { 2153 TagD = DS.getRepAsDecl(); 2154 2155 if (!TagD) // We probably had an error 2156 return 0; 2157 2158 // Note that the above type specs guarantee that the 2159 // type rep is a Decl, whereas in many of the others 2160 // it's a Type. 2161 Tag = dyn_cast<TagDecl>(TagD); 2162 } 2163 2164 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 2165 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 2166 // or incomplete types shall not be restrict-qualified." 2167 if (TypeQuals & DeclSpec::TQ_restrict) 2168 Diag(DS.getRestrictSpecLoc(), 2169 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 2170 << DS.getSourceRange(); 2171 } 2172 2173 if (DS.isFriendSpecified()) { 2174 // If we're dealing with a decl but not a TagDecl, assume that 2175 // whatever routines created it handled the friendship aspect. 2176 if (TagD && !Tag) 2177 return 0; 2178 return ActOnFriendTypeDecl(S, DS, TemplateParams); 2179 } 2180 2181 // Track whether we warned about the fact that there aren't any 2182 // declarators. 2183 bool emittedWarning = false; 2184 2185 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 2186 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 2187 2188 if (!Record->getDeclName() && Record->isDefinition() && 2189 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 2190 if (getLangOptions().CPlusPlus || 2191 Record->getDeclContext()->isRecord()) 2192 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 2193 2194 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 2195 << DS.getSourceRange(); 2196 emittedWarning = true; 2197 } 2198 } 2199 2200 // Check for Microsoft C extension: anonymous struct. 2201 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 2202 CurContext->isRecord() && 2203 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 2204 // Handle 2 kinds of anonymous struct: 2205 // struct STRUCT; 2206 // and 2207 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 2208 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 2209 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 2210 (DS.getTypeSpecType() == DeclSpec::TST_typename && 2211 DS.getRepAsType().get()->isStructureType())) { 2212 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 2213 << DS.getSourceRange(); 2214 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 2215 } 2216 } 2217 2218 if (getLangOptions().CPlusPlus && 2219 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 2220 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 2221 if (Enum->enumerator_begin() == Enum->enumerator_end() && 2222 !Enum->getIdentifier() && !Enum->isInvalidDecl()) { 2223 Diag(Enum->getLocation(), diag::ext_no_declarators) 2224 << DS.getSourceRange(); 2225 emittedWarning = true; 2226 } 2227 2228 // Skip all the checks below if we have a type error. 2229 if (DS.getTypeSpecType() == DeclSpec::TST_error) return TagD; 2230 2231 if (!DS.isMissingDeclaratorOk()) { 2232 // Warn about typedefs of enums without names, since this is an 2233 // extension in both Microsoft and GNU. 2234 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 2235 Tag && isa<EnumDecl>(Tag)) { 2236 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 2237 << DS.getSourceRange(); 2238 return Tag; 2239 } 2240 2241 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 2242 << DS.getSourceRange(); 2243 emittedWarning = true; 2244 } 2245 2246 // We're going to complain about a bunch of spurious specifiers; 2247 // only do this if we're declaring a tag, because otherwise we 2248 // should be getting diag::ext_no_declarators. 2249 if (emittedWarning || (TagD && TagD->isInvalidDecl())) 2250 return TagD; 2251 2252 // Note that a linkage-specification sets a storage class, but 2253 // 'extern "C" struct foo;' is actually valid and not theoretically 2254 // useless. 2255 if (DeclSpec::SCS scs = DS.getStorageClassSpec()) 2256 if (!DS.isExternInLinkageSpec()) 2257 Diag(DS.getStorageClassSpecLoc(), diag::warn_standalone_specifier) 2258 << DeclSpec::getSpecifierName(scs); 2259 2260 if (DS.isThreadSpecified()) 2261 Diag(DS.getThreadSpecLoc(), diag::warn_standalone_specifier) << "__thread"; 2262 if (DS.getTypeQualifiers()) { 2263 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 2264 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "const"; 2265 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 2266 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "volatile"; 2267 // Restrict is covered above. 2268 } 2269 if (DS.isInlineSpecified()) 2270 Diag(DS.getInlineSpecLoc(), diag::warn_standalone_specifier) << "inline"; 2271 if (DS.isVirtualSpecified()) 2272 Diag(DS.getVirtualSpecLoc(), diag::warn_standalone_specifier) << "virtual"; 2273 if (DS.isExplicitSpecified()) 2274 Diag(DS.getExplicitSpecLoc(), diag::warn_standalone_specifier) <<"explicit"; 2275 2276 // FIXME: Warn on useless attributes 2277 2278 return TagD; 2279} 2280 2281/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 2282/// builds a statement for it and returns it so it is evaluated. 2283StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 2284 StmtResult R; 2285 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 2286 Expr *Exp = DS.getRepAsExpr(); 2287 QualType Ty = Exp->getType(); 2288 if (Ty->isPointerType()) { 2289 do 2290 Ty = Ty->getAs<PointerType>()->getPointeeType(); 2291 while (Ty->isPointerType()); 2292 } 2293 if (Ty->isVariableArrayType()) { 2294 R = ActOnExprStmt(MakeFullExpr(Exp)); 2295 } 2296 } 2297 return R; 2298} 2299 2300/// We are trying to inject an anonymous member into the given scope; 2301/// check if there's an existing declaration that can't be overloaded. 2302/// 2303/// \return true if this is a forbidden redeclaration 2304static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 2305 Scope *S, 2306 DeclContext *Owner, 2307 DeclarationName Name, 2308 SourceLocation NameLoc, 2309 unsigned diagnostic) { 2310 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 2311 Sema::ForRedeclaration); 2312 if (!SemaRef.LookupName(R, S)) return false; 2313 2314 if (R.getAsSingle<TagDecl>()) 2315 return false; 2316 2317 // Pick a representative declaration. 2318 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 2319 assert(PrevDecl && "Expected a non-null Decl"); 2320 2321 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 2322 return false; 2323 2324 SemaRef.Diag(NameLoc, diagnostic) << Name; 2325 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 2326 2327 return true; 2328} 2329 2330/// InjectAnonymousStructOrUnionMembers - Inject the members of the 2331/// anonymous struct or union AnonRecord into the owning context Owner 2332/// and scope S. This routine will be invoked just after we realize 2333/// that an unnamed union or struct is actually an anonymous union or 2334/// struct, e.g., 2335/// 2336/// @code 2337/// union { 2338/// int i; 2339/// float f; 2340/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 2341/// // f into the surrounding scope.x 2342/// @endcode 2343/// 2344/// This routine is recursive, injecting the names of nested anonymous 2345/// structs/unions into the owning context and scope as well. 2346static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 2347 DeclContext *Owner, 2348 RecordDecl *AnonRecord, 2349 AccessSpecifier AS, 2350 llvm::SmallVector<NamedDecl*, 2> &Chaining, 2351 bool MSAnonStruct) { 2352 unsigned diagKind 2353 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 2354 : diag::err_anonymous_struct_member_redecl; 2355 2356 bool Invalid = false; 2357 2358 // Look every FieldDecl and IndirectFieldDecl with a name. 2359 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 2360 DEnd = AnonRecord->decls_end(); 2361 D != DEnd; ++D) { 2362 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 2363 cast<NamedDecl>(*D)->getDeclName()) { 2364 ValueDecl *VD = cast<ValueDecl>(*D); 2365 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 2366 VD->getLocation(), diagKind)) { 2367 // C++ [class.union]p2: 2368 // The names of the members of an anonymous union shall be 2369 // distinct from the names of any other entity in the 2370 // scope in which the anonymous union is declared. 2371 Invalid = true; 2372 } else { 2373 // C++ [class.union]p2: 2374 // For the purpose of name lookup, after the anonymous union 2375 // definition, the members of the anonymous union are 2376 // considered to have been defined in the scope in which the 2377 // anonymous union is declared. 2378 unsigned OldChainingSize = Chaining.size(); 2379 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 2380 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 2381 PE = IF->chain_end(); PI != PE; ++PI) 2382 Chaining.push_back(*PI); 2383 else 2384 Chaining.push_back(VD); 2385 2386 assert(Chaining.size() >= 2); 2387 NamedDecl **NamedChain = 2388 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 2389 for (unsigned i = 0; i < Chaining.size(); i++) 2390 NamedChain[i] = Chaining[i]; 2391 2392 IndirectFieldDecl* IndirectField = 2393 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 2394 VD->getIdentifier(), VD->getType(), 2395 NamedChain, Chaining.size()); 2396 2397 IndirectField->setAccess(AS); 2398 IndirectField->setImplicit(); 2399 SemaRef.PushOnScopeChains(IndirectField, S); 2400 2401 // That includes picking up the appropriate access specifier. 2402 if (AS != AS_none) IndirectField->setAccess(AS); 2403 2404 Chaining.resize(OldChainingSize); 2405 } 2406 } 2407 } 2408 2409 return Invalid; 2410} 2411 2412/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 2413/// a VarDecl::StorageClass. Any error reporting is up to the caller: 2414/// illegal input values are mapped to SC_None. 2415static StorageClass 2416StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2417 switch (StorageClassSpec) { 2418 case DeclSpec::SCS_unspecified: return SC_None; 2419 case DeclSpec::SCS_extern: return SC_Extern; 2420 case DeclSpec::SCS_static: return SC_Static; 2421 case DeclSpec::SCS_auto: return SC_Auto; 2422 case DeclSpec::SCS_register: return SC_Register; 2423 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2424 // Illegal SCSs map to None: error reporting is up to the caller. 2425 case DeclSpec::SCS_mutable: // Fall through. 2426 case DeclSpec::SCS_typedef: return SC_None; 2427 } 2428 llvm_unreachable("unknown storage class specifier"); 2429} 2430 2431/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 2432/// a StorageClass. Any error reporting is up to the caller: 2433/// illegal input values are mapped to SC_None. 2434static StorageClass 2435StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2436 switch (StorageClassSpec) { 2437 case DeclSpec::SCS_unspecified: return SC_None; 2438 case DeclSpec::SCS_extern: return SC_Extern; 2439 case DeclSpec::SCS_static: return SC_Static; 2440 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2441 // Illegal SCSs map to None: error reporting is up to the caller. 2442 case DeclSpec::SCS_auto: // Fall through. 2443 case DeclSpec::SCS_mutable: // Fall through. 2444 case DeclSpec::SCS_register: // Fall through. 2445 case DeclSpec::SCS_typedef: return SC_None; 2446 } 2447 llvm_unreachable("unknown storage class specifier"); 2448} 2449 2450/// BuildAnonymousStructOrUnion - Handle the declaration of an 2451/// anonymous structure or union. Anonymous unions are a C++ feature 2452/// (C++ [class.union]) and a GNU C extension; anonymous structures 2453/// are a GNU C and GNU C++ extension. 2454Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2455 AccessSpecifier AS, 2456 RecordDecl *Record) { 2457 DeclContext *Owner = Record->getDeclContext(); 2458 2459 // Diagnose whether this anonymous struct/union is an extension. 2460 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2461 Diag(Record->getLocation(), diag::ext_anonymous_union); 2462 else if (!Record->isUnion()) 2463 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2464 2465 // C and C++ require different kinds of checks for anonymous 2466 // structs/unions. 2467 bool Invalid = false; 2468 if (getLangOptions().CPlusPlus) { 2469 const char* PrevSpec = 0; 2470 unsigned DiagID; 2471 // C++ [class.union]p3: 2472 // Anonymous unions declared in a named namespace or in the 2473 // global namespace shall be declared static. 2474 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2475 (isa<TranslationUnitDecl>(Owner) || 2476 (isa<NamespaceDecl>(Owner) && 2477 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2478 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2479 Invalid = true; 2480 2481 // Recover by adding 'static'. 2482 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2483 PrevSpec, DiagID, getLangOptions()); 2484 } 2485 // C++ [class.union]p3: 2486 // A storage class is not allowed in a declaration of an 2487 // anonymous union in a class scope. 2488 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2489 isa<RecordDecl>(Owner)) { 2490 Diag(DS.getStorageClassSpecLoc(), 2491 diag::err_anonymous_union_with_storage_spec); 2492 Invalid = true; 2493 2494 // Recover by removing the storage specifier. 2495 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2496 PrevSpec, DiagID, getLangOptions()); 2497 } 2498 2499 // Ignore const/volatile/restrict qualifiers. 2500 if (DS.getTypeQualifiers()) { 2501 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 2502 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified) 2503 << Record->isUnion() << 0 2504 << FixItHint::CreateRemoval(DS.getConstSpecLoc()); 2505 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 2506 Diag(DS.getVolatileSpecLoc(), diag::ext_anonymous_struct_union_qualified) 2507 << Record->isUnion() << 1 2508 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc()); 2509 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict) 2510 Diag(DS.getRestrictSpecLoc(), diag::ext_anonymous_struct_union_qualified) 2511 << Record->isUnion() << 2 2512 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc()); 2513 2514 DS.ClearTypeQualifiers(); 2515 } 2516 2517 // C++ [class.union]p2: 2518 // The member-specification of an anonymous union shall only 2519 // define non-static data members. [Note: nested types and 2520 // functions cannot be declared within an anonymous union. ] 2521 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2522 MemEnd = Record->decls_end(); 2523 Mem != MemEnd; ++Mem) { 2524 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2525 // C++ [class.union]p3: 2526 // An anonymous union shall not have private or protected 2527 // members (clause 11). 2528 assert(FD->getAccess() != AS_none); 2529 if (FD->getAccess() != AS_public) { 2530 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2531 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2532 Invalid = true; 2533 } 2534 2535 // C++ [class.union]p1 2536 // An object of a class with a non-trivial constructor, a non-trivial 2537 // copy constructor, a non-trivial destructor, or a non-trivial copy 2538 // assignment operator cannot be a member of a union, nor can an 2539 // array of such objects. 2540 if (!getLangOptions().CPlusPlus0x && CheckNontrivialField(FD)) 2541 Invalid = true; 2542 } else if ((*Mem)->isImplicit()) { 2543 // Any implicit members are fine. 2544 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2545 // This is a type that showed up in an 2546 // elaborated-type-specifier inside the anonymous struct or 2547 // union, but which actually declares a type outside of the 2548 // anonymous struct or union. It's okay. 2549 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2550 if (!MemRecord->isAnonymousStructOrUnion() && 2551 MemRecord->getDeclName()) { 2552 // Visual C++ allows type definition in anonymous struct or union. 2553 if (getLangOptions().Microsoft) 2554 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2555 << (int)Record->isUnion(); 2556 else { 2557 // This is a nested type declaration. 2558 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2559 << (int)Record->isUnion(); 2560 Invalid = true; 2561 } 2562 } 2563 } else if (isa<AccessSpecDecl>(*Mem)) { 2564 // Any access specifier is fine. 2565 } else { 2566 // We have something that isn't a non-static data 2567 // member. Complain about it. 2568 unsigned DK = diag::err_anonymous_record_bad_member; 2569 if (isa<TypeDecl>(*Mem)) 2570 DK = diag::err_anonymous_record_with_type; 2571 else if (isa<FunctionDecl>(*Mem)) 2572 DK = diag::err_anonymous_record_with_function; 2573 else if (isa<VarDecl>(*Mem)) 2574 DK = diag::err_anonymous_record_with_static; 2575 2576 // Visual C++ allows type definition in anonymous struct or union. 2577 if (getLangOptions().Microsoft && 2578 DK == diag::err_anonymous_record_with_type) 2579 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2580 << (int)Record->isUnion(); 2581 else { 2582 Diag((*Mem)->getLocation(), DK) 2583 << (int)Record->isUnion(); 2584 Invalid = true; 2585 } 2586 } 2587 } 2588 } 2589 2590 if (!Record->isUnion() && !Owner->isRecord()) { 2591 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2592 << (int)getLangOptions().CPlusPlus; 2593 Invalid = true; 2594 } 2595 2596 // Mock up a declarator. 2597 Declarator Dc(DS, Declarator::TypeNameContext); 2598 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2599 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2600 2601 // Create a declaration for this anonymous struct/union. 2602 NamedDecl *Anon = 0; 2603 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2604 Anon = FieldDecl::Create(Context, OwningClass, 2605 DS.getSourceRange().getBegin(), 2606 Record->getLocation(), 2607 /*IdentifierInfo=*/0, 2608 Context.getTypeDeclType(Record), 2609 TInfo, 2610 /*BitWidth=*/0, /*Mutable=*/false); 2611 Anon->setAccess(AS); 2612 if (getLangOptions().CPlusPlus) 2613 FieldCollector->Add(cast<FieldDecl>(Anon)); 2614 } else { 2615 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2616 assert(SCSpec != DeclSpec::SCS_typedef && 2617 "Parser allowed 'typedef' as storage class VarDecl."); 2618 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2619 if (SCSpec == DeclSpec::SCS_mutable) { 2620 // mutable can only appear on non-static class members, so it's always 2621 // an error here 2622 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2623 Invalid = true; 2624 SC = SC_None; 2625 } 2626 SCSpec = DS.getStorageClassSpecAsWritten(); 2627 VarDecl::StorageClass SCAsWritten 2628 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2629 2630 Anon = VarDecl::Create(Context, Owner, 2631 DS.getSourceRange().getBegin(), 2632 Record->getLocation(), /*IdentifierInfo=*/0, 2633 Context.getTypeDeclType(Record), 2634 TInfo, SC, SCAsWritten); 2635 } 2636 Anon->setImplicit(); 2637 2638 // Add the anonymous struct/union object to the current 2639 // context. We'll be referencing this object when we refer to one of 2640 // its members. 2641 Owner->addDecl(Anon); 2642 2643 // Inject the members of the anonymous struct/union into the owning 2644 // context and into the identifier resolver chain for name lookup 2645 // purposes. 2646 llvm::SmallVector<NamedDecl*, 2> Chain; 2647 Chain.push_back(Anon); 2648 2649 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2650 Chain, false)) 2651 Invalid = true; 2652 2653 // Mark this as an anonymous struct/union type. Note that we do not 2654 // do this until after we have already checked and injected the 2655 // members of this anonymous struct/union type, because otherwise 2656 // the members could be injected twice: once by DeclContext when it 2657 // builds its lookup table, and once by 2658 // InjectAnonymousStructOrUnionMembers. 2659 Record->setAnonymousStructOrUnion(true); 2660 2661 if (Invalid) 2662 Anon->setInvalidDecl(); 2663 2664 return Anon; 2665} 2666 2667/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2668/// Microsoft C anonymous structure. 2669/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2670/// Example: 2671/// 2672/// struct A { int a; }; 2673/// struct B { struct A; int b; }; 2674/// 2675/// void foo() { 2676/// B var; 2677/// var.a = 3; 2678/// } 2679/// 2680Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2681 RecordDecl *Record) { 2682 2683 // If there is no Record, get the record via the typedef. 2684 if (!Record) 2685 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2686 2687 // Mock up a declarator. 2688 Declarator Dc(DS, Declarator::TypeNameContext); 2689 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2690 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2691 2692 // Create a declaration for this anonymous struct. 2693 NamedDecl* Anon = FieldDecl::Create(Context, 2694 cast<RecordDecl>(CurContext), 2695 DS.getSourceRange().getBegin(), 2696 DS.getSourceRange().getBegin(), 2697 /*IdentifierInfo=*/0, 2698 Context.getTypeDeclType(Record), 2699 TInfo, 2700 /*BitWidth=*/0, /*Mutable=*/false); 2701 Anon->setImplicit(); 2702 2703 // Add the anonymous struct object to the current context. 2704 CurContext->addDecl(Anon); 2705 2706 // Inject the members of the anonymous struct into the current 2707 // context and into the identifier resolver chain for name lookup 2708 // purposes. 2709 llvm::SmallVector<NamedDecl*, 2> Chain; 2710 Chain.push_back(Anon); 2711 2712 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2713 Record->getDefinition(), 2714 AS_none, Chain, true)) 2715 Anon->setInvalidDecl(); 2716 2717 return Anon; 2718} 2719 2720/// GetNameForDeclarator - Determine the full declaration name for the 2721/// given Declarator. 2722DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2723 return GetNameFromUnqualifiedId(D.getName()); 2724} 2725 2726/// \brief Retrieves the declaration name from a parsed unqualified-id. 2727DeclarationNameInfo 2728Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2729 DeclarationNameInfo NameInfo; 2730 NameInfo.setLoc(Name.StartLocation); 2731 2732 switch (Name.getKind()) { 2733 2734 case UnqualifiedId::IK_Identifier: 2735 NameInfo.setName(Name.Identifier); 2736 NameInfo.setLoc(Name.StartLocation); 2737 return NameInfo; 2738 2739 case UnqualifiedId::IK_OperatorFunctionId: 2740 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2741 Name.OperatorFunctionId.Operator)); 2742 NameInfo.setLoc(Name.StartLocation); 2743 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2744 = Name.OperatorFunctionId.SymbolLocations[0]; 2745 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2746 = Name.EndLocation.getRawEncoding(); 2747 return NameInfo; 2748 2749 case UnqualifiedId::IK_LiteralOperatorId: 2750 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2751 Name.Identifier)); 2752 NameInfo.setLoc(Name.StartLocation); 2753 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2754 return NameInfo; 2755 2756 case UnqualifiedId::IK_ConversionFunctionId: { 2757 TypeSourceInfo *TInfo; 2758 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2759 if (Ty.isNull()) 2760 return DeclarationNameInfo(); 2761 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2762 Context.getCanonicalType(Ty))); 2763 NameInfo.setLoc(Name.StartLocation); 2764 NameInfo.setNamedTypeInfo(TInfo); 2765 return NameInfo; 2766 } 2767 2768 case UnqualifiedId::IK_ConstructorName: { 2769 TypeSourceInfo *TInfo; 2770 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2771 if (Ty.isNull()) 2772 return DeclarationNameInfo(); 2773 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2774 Context.getCanonicalType(Ty))); 2775 NameInfo.setLoc(Name.StartLocation); 2776 NameInfo.setNamedTypeInfo(TInfo); 2777 return NameInfo; 2778 } 2779 2780 case UnqualifiedId::IK_ConstructorTemplateId: { 2781 // In well-formed code, we can only have a constructor 2782 // template-id that refers to the current context, so go there 2783 // to find the actual type being constructed. 2784 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2785 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2786 return DeclarationNameInfo(); 2787 2788 // Determine the type of the class being constructed. 2789 QualType CurClassType = Context.getTypeDeclType(CurClass); 2790 2791 // FIXME: Check two things: that the template-id names the same type as 2792 // CurClassType, and that the template-id does not occur when the name 2793 // was qualified. 2794 2795 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2796 Context.getCanonicalType(CurClassType))); 2797 NameInfo.setLoc(Name.StartLocation); 2798 // FIXME: should we retrieve TypeSourceInfo? 2799 NameInfo.setNamedTypeInfo(0); 2800 return NameInfo; 2801 } 2802 2803 case UnqualifiedId::IK_DestructorName: { 2804 TypeSourceInfo *TInfo; 2805 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2806 if (Ty.isNull()) 2807 return DeclarationNameInfo(); 2808 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2809 Context.getCanonicalType(Ty))); 2810 NameInfo.setLoc(Name.StartLocation); 2811 NameInfo.setNamedTypeInfo(TInfo); 2812 return NameInfo; 2813 } 2814 2815 case UnqualifiedId::IK_TemplateId: { 2816 TemplateName TName = Name.TemplateId->Template.get(); 2817 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2818 return Context.getNameForTemplate(TName, TNameLoc); 2819 } 2820 2821 } // switch (Name.getKind()) 2822 2823 assert(false && "Unknown name kind"); 2824 return DeclarationNameInfo(); 2825} 2826 2827/// isNearlyMatchingFunction - Determine whether the C++ functions 2828/// Declaration and Definition are "nearly" matching. This heuristic 2829/// is used to improve diagnostics in the case where an out-of-line 2830/// function definition doesn't match any declaration within 2831/// the class or namespace. 2832static bool isNearlyMatchingFunction(ASTContext &Context, 2833 FunctionDecl *Declaration, 2834 FunctionDecl *Definition) { 2835 if (Declaration->param_size() != Definition->param_size()) 2836 return false; 2837 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2838 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2839 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2840 2841 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2842 DefParamTy.getNonReferenceType())) 2843 return false; 2844 } 2845 2846 return true; 2847} 2848 2849/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2850/// declarator needs to be rebuilt in the current instantiation. 2851/// Any bits of declarator which appear before the name are valid for 2852/// consideration here. That's specifically the type in the decl spec 2853/// and the base type in any member-pointer chunks. 2854static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2855 DeclarationName Name) { 2856 // The types we specifically need to rebuild are: 2857 // - typenames, typeofs, and decltypes 2858 // - types which will become injected class names 2859 // Of course, we also need to rebuild any type referencing such a 2860 // type. It's safest to just say "dependent", but we call out a 2861 // few cases here. 2862 2863 DeclSpec &DS = D.getMutableDeclSpec(); 2864 switch (DS.getTypeSpecType()) { 2865 case DeclSpec::TST_typename: 2866 case DeclSpec::TST_typeofType: 2867 case DeclSpec::TST_decltype: 2868 case DeclSpec::TST_underlying_type: { 2869 // Grab the type from the parser. 2870 TypeSourceInfo *TSI = 0; 2871 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2872 if (T.isNull() || !T->isDependentType()) break; 2873 2874 // Make sure there's a type source info. This isn't really much 2875 // of a waste; most dependent types should have type source info 2876 // attached already. 2877 if (!TSI) 2878 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2879 2880 // Rebuild the type in the current instantiation. 2881 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2882 if (!TSI) return true; 2883 2884 // Store the new type back in the decl spec. 2885 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2886 DS.UpdateTypeRep(LocType); 2887 break; 2888 } 2889 2890 case DeclSpec::TST_typeofExpr: { 2891 Expr *E = DS.getRepAsExpr(); 2892 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2893 if (Result.isInvalid()) return true; 2894 DS.UpdateExprRep(Result.get()); 2895 break; 2896 } 2897 2898 default: 2899 // Nothing to do for these decl specs. 2900 break; 2901 } 2902 2903 // It doesn't matter what order we do this in. 2904 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2905 DeclaratorChunk &Chunk = D.getTypeObject(I); 2906 2907 // The only type information in the declarator which can come 2908 // before the declaration name is the base type of a member 2909 // pointer. 2910 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2911 continue; 2912 2913 // Rebuild the scope specifier in-place. 2914 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2915 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2916 return true; 2917 } 2918 2919 return false; 2920} 2921 2922Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D, 2923 bool IsFunctionDefinition) { 2924 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), 2925 IsFunctionDefinition); 2926} 2927 2928/// DiagnoseClassNameShadow - Implement C++ [class.mem]p13: 2929/// If T is the name of a class, then each of the following shall have a 2930/// name different from T: 2931/// - every static data member of class T; 2932/// - every member function of class T 2933/// - every member of class T that is itself a type; 2934/// \returns true if the declaration name violates these rules. 2935bool Sema::DiagnoseClassNameShadow(DeclContext *DC, 2936 DeclarationNameInfo NameInfo) { 2937 DeclarationName Name = NameInfo.getName(); 2938 2939 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2940 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2941 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name; 2942 return true; 2943 } 2944 2945 return false; 2946} 2947 2948Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2949 MultiTemplateParamsArg TemplateParamLists, 2950 bool IsFunctionDefinition) { 2951 // TODO: consider using NameInfo for diagnostic. 2952 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2953 DeclarationName Name = NameInfo.getName(); 2954 2955 // All of these full declarators require an identifier. If it doesn't have 2956 // one, the ParsedFreeStandingDeclSpec action should be used. 2957 if (!Name) { 2958 if (!D.isInvalidType()) // Reject this if we think it is valid. 2959 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2960 diag::err_declarator_need_ident) 2961 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2962 return 0; 2963 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2964 return 0; 2965 2966 // The scope passed in may not be a decl scope. Zip up the scope tree until 2967 // we find one that is. 2968 while ((S->getFlags() & Scope::DeclScope) == 0 || 2969 (S->getFlags() & Scope::TemplateParamScope) != 0) 2970 S = S->getParent(); 2971 2972 DeclContext *DC = CurContext; 2973 if (D.getCXXScopeSpec().isInvalid()) 2974 D.setInvalidType(); 2975 else if (D.getCXXScopeSpec().isSet()) { 2976 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2977 UPPC_DeclarationQualifier)) 2978 return 0; 2979 2980 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2981 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2982 if (!DC) { 2983 // If we could not compute the declaration context, it's because the 2984 // declaration context is dependent but does not refer to a class, 2985 // class template, or class template partial specialization. Complain 2986 // and return early, to avoid the coming semantic disaster. 2987 Diag(D.getIdentifierLoc(), 2988 diag::err_template_qualified_declarator_no_match) 2989 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2990 << D.getCXXScopeSpec().getRange(); 2991 return 0; 2992 } 2993 bool IsDependentContext = DC->isDependentContext(); 2994 2995 if (!IsDependentContext && 2996 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2997 return 0; 2998 2999 if (isa<CXXRecordDecl>(DC)) { 3000 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 3001 Diag(D.getIdentifierLoc(), 3002 diag::err_member_def_undefined_record) 3003 << Name << DC << D.getCXXScopeSpec().getRange(); 3004 D.setInvalidType(); 3005 } else if (isa<CXXRecordDecl>(CurContext) && 3006 !D.getDeclSpec().isFriendSpecified()) { 3007 // The user provided a superfluous scope specifier inside a class 3008 // definition: 3009 // 3010 // class X { 3011 // void X::f(); 3012 // }; 3013 if (CurContext->Equals(DC)) 3014 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 3015 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 3016 else 3017 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 3018 << Name << D.getCXXScopeSpec().getRange(); 3019 3020 // Pretend that this qualifier was not here. 3021 D.getCXXScopeSpec().clear(); 3022 } 3023 } 3024 3025 // Check whether we need to rebuild the type of the given 3026 // declaration in the current instantiation. 3027 if (EnteringContext && IsDependentContext && 3028 TemplateParamLists.size() != 0) { 3029 ContextRAII SavedContext(*this, DC); 3030 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 3031 D.setInvalidType(); 3032 } 3033 } 3034 3035 if (DiagnoseClassNameShadow(DC, NameInfo)) 3036 // If this is a typedef, we'll end up spewing multiple diagnostics. 3037 // Just return early; it's safer. 3038 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 3039 return 0; 3040 3041 NamedDecl *New; 3042 3043 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 3044 QualType R = TInfo->getType(); 3045 3046 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 3047 UPPC_DeclarationType)) 3048 D.setInvalidType(); 3049 3050 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 3051 ForRedeclaration); 3052 3053 // See if this is a redefinition of a variable in the same scope. 3054 if (!D.getCXXScopeSpec().isSet()) { 3055 bool IsLinkageLookup = false; 3056 3057 // If the declaration we're planning to build will be a function 3058 // or object with linkage, then look for another declaration with 3059 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 3060 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 3061 /* Do nothing*/; 3062 else if (R->isFunctionType()) { 3063 if (CurContext->isFunctionOrMethod() || 3064 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 3065 IsLinkageLookup = true; 3066 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 3067 IsLinkageLookup = true; 3068 else if (CurContext->getRedeclContext()->isTranslationUnit() && 3069 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 3070 IsLinkageLookup = true; 3071 3072 if (IsLinkageLookup) 3073 Previous.clear(LookupRedeclarationWithLinkage); 3074 3075 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 3076 } else { // Something like "int foo::x;" 3077 LookupQualifiedName(Previous, DC); 3078 3079 // Don't consider using declarations as previous declarations for 3080 // out-of-line members. 3081 RemoveUsingDecls(Previous); 3082 3083 // C++ 7.3.1.2p2: 3084 // Members (including explicit specializations of templates) of a named 3085 // namespace can also be defined outside that namespace by explicit 3086 // qualification of the name being defined, provided that the entity being 3087 // defined was already declared in the namespace and the definition appears 3088 // after the point of declaration in a namespace that encloses the 3089 // declarations namespace. 3090 // 3091 // Note that we only check the context at this point. We don't yet 3092 // have enough information to make sure that PrevDecl is actually 3093 // the declaration we want to match. For example, given: 3094 // 3095 // class X { 3096 // void f(); 3097 // void f(float); 3098 // }; 3099 // 3100 // void X::f(int) { } // ill-formed 3101 // 3102 // In this case, PrevDecl will point to the overload set 3103 // containing the two f's declared in X, but neither of them 3104 // matches. 3105 3106 // First check whether we named the global scope. 3107 if (isa<TranslationUnitDecl>(DC)) { 3108 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 3109 << Name << D.getCXXScopeSpec().getRange(); 3110 } else { 3111 DeclContext *Cur = CurContext; 3112 while (isa<LinkageSpecDecl>(Cur)) 3113 Cur = Cur->getParent(); 3114 if (!Cur->Encloses(DC)) { 3115 // The qualifying scope doesn't enclose the original declaration. 3116 // Emit diagnostic based on current scope. 3117 SourceLocation L = D.getIdentifierLoc(); 3118 SourceRange R = D.getCXXScopeSpec().getRange(); 3119 if (isa<FunctionDecl>(Cur)) 3120 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 3121 else 3122 Diag(L, diag::err_invalid_declarator_scope) 3123 << Name << cast<NamedDecl>(DC) << R; 3124 D.setInvalidType(); 3125 } 3126 } 3127 } 3128 3129 if (Previous.isSingleResult() && 3130 Previous.getFoundDecl()->isTemplateParameter()) { 3131 // Maybe we will complain about the shadowed template parameter. 3132 if (!D.isInvalidType()) 3133 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 3134 Previous.getFoundDecl())) 3135 D.setInvalidType(); 3136 3137 // Just pretend that we didn't see the previous declaration. 3138 Previous.clear(); 3139 } 3140 3141 // In C++, the previous declaration we find might be a tag type 3142 // (class or enum). In this case, the new declaration will hide the 3143 // tag type. Note that this does does not apply if we're declaring a 3144 // typedef (C++ [dcl.typedef]p4). 3145 if (Previous.isSingleTagDecl() && 3146 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 3147 Previous.clear(); 3148 3149 bool Redeclaration = false; 3150 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 3151 if (TemplateParamLists.size()) { 3152 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 3153 return 0; 3154 } 3155 3156 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 3157 } else if (R->isFunctionType()) { 3158 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 3159 move(TemplateParamLists), 3160 IsFunctionDefinition, Redeclaration); 3161 } else { 3162 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 3163 move(TemplateParamLists), 3164 Redeclaration); 3165 } 3166 3167 if (New == 0) 3168 return 0; 3169 3170 // If this has an identifier and is not an invalid redeclaration or 3171 // function template specialization, add it to the scope stack. 3172 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 3173 PushOnScopeChains(New, S); 3174 3175 return New; 3176} 3177 3178/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3179/// types into constant array types in certain situations which would otherwise 3180/// be errors (for GCC compatibility). 3181static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3182 ASTContext &Context, 3183 bool &SizeIsNegative, 3184 llvm::APSInt &Oversized) { 3185 // This method tries to turn a variable array into a constant 3186 // array even when the size isn't an ICE. This is necessary 3187 // for compatibility with code that depends on gcc's buggy 3188 // constant expression folding, like struct {char x[(int)(char*)2];} 3189 SizeIsNegative = false; 3190 Oversized = 0; 3191 3192 if (T->isDependentType()) 3193 return QualType(); 3194 3195 QualifierCollector Qs; 3196 const Type *Ty = Qs.strip(T); 3197 3198 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 3199 QualType Pointee = PTy->getPointeeType(); 3200 QualType FixedType = 3201 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 3202 Oversized); 3203 if (FixedType.isNull()) return FixedType; 3204 FixedType = Context.getPointerType(FixedType); 3205 return Qs.apply(Context, FixedType); 3206 } 3207 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 3208 QualType Inner = PTy->getInnerType(); 3209 QualType FixedType = 3210 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 3211 Oversized); 3212 if (FixedType.isNull()) return FixedType; 3213 FixedType = Context.getParenType(FixedType); 3214 return Qs.apply(Context, FixedType); 3215 } 3216 3217 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3218 if (!VLATy) 3219 return QualType(); 3220 // FIXME: We should probably handle this case 3221 if (VLATy->getElementType()->isVariablyModifiedType()) 3222 return QualType(); 3223 3224 Expr::EvalResult EvalResult; 3225 if (!VLATy->getSizeExpr() || 3226 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 3227 !EvalResult.Val.isInt()) 3228 return QualType(); 3229 3230 // Check whether the array size is negative. 3231 llvm::APSInt &Res = EvalResult.Val.getInt(); 3232 if (Res.isSigned() && Res.isNegative()) { 3233 SizeIsNegative = true; 3234 return QualType(); 3235 } 3236 3237 // Check whether the array is too large to be addressed. 3238 unsigned ActiveSizeBits 3239 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 3240 Res); 3241 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 3242 Oversized = Res; 3243 return QualType(); 3244 } 3245 3246 return Context.getConstantArrayType(VLATy->getElementType(), 3247 Res, ArrayType::Normal, 0); 3248} 3249 3250/// \brief Register the given locally-scoped external C declaration so 3251/// that it can be found later for redeclarations 3252void 3253Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 3254 const LookupResult &Previous, 3255 Scope *S) { 3256 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 3257 "Decl is not a locally-scoped decl!"); 3258 // Note that we have a locally-scoped external with this name. 3259 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 3260 3261 if (!Previous.isSingleResult()) 3262 return; 3263 3264 NamedDecl *PrevDecl = Previous.getFoundDecl(); 3265 3266 // If there was a previous declaration of this variable, it may be 3267 // in our identifier chain. Update the identifier chain with the new 3268 // declaration. 3269 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 3270 // The previous declaration was found on the identifer resolver 3271 // chain, so remove it from its scope. 3272 while (S && !S->isDeclScope(PrevDecl)) 3273 S = S->getParent(); 3274 3275 if (S) 3276 S->RemoveDecl(PrevDecl); 3277 } 3278} 3279 3280/// \brief Diagnose function specifiers on a declaration of an identifier that 3281/// does not identify a function. 3282void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 3283 // FIXME: We should probably indicate the identifier in question to avoid 3284 // confusion for constructs like "inline int a(), b;" 3285 if (D.getDeclSpec().isInlineSpecified()) 3286 Diag(D.getDeclSpec().getInlineSpecLoc(), 3287 diag::err_inline_non_function); 3288 3289 if (D.getDeclSpec().isVirtualSpecified()) 3290 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3291 diag::err_virtual_non_function); 3292 3293 if (D.getDeclSpec().isExplicitSpecified()) 3294 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3295 diag::err_explicit_non_function); 3296} 3297 3298NamedDecl* 3299Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3300 QualType R, TypeSourceInfo *TInfo, 3301 LookupResult &Previous, bool &Redeclaration) { 3302 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 3303 if (D.getCXXScopeSpec().isSet()) { 3304 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 3305 << D.getCXXScopeSpec().getRange(); 3306 D.setInvalidType(); 3307 // Pretend we didn't see the scope specifier. 3308 DC = CurContext; 3309 Previous.clear(); 3310 } 3311 3312 if (getLangOptions().CPlusPlus) { 3313 // Check that there are no default arguments (C++ only). 3314 CheckExtraCXXDefaultArguments(D); 3315 } 3316 3317 DiagnoseFunctionSpecifiers(D); 3318 3319 if (D.getDeclSpec().isThreadSpecified()) 3320 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3321 3322 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 3323 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 3324 << D.getName().getSourceRange(); 3325 return 0; 3326 } 3327 3328 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 3329 if (!NewTD) return 0; 3330 3331 // Handle attributes prior to checking for duplicates in MergeVarDecl 3332 ProcessDeclAttributes(S, NewTD, D); 3333 3334 CheckTypedefForVariablyModifiedType(S, NewTD); 3335 3336 return ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration); 3337} 3338 3339void 3340Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) { 3341 // C99 6.7.7p2: If a typedef name specifies a variably modified type 3342 // then it shall have block scope. 3343 // Note that variably modified types must be fixed before merging the decl so 3344 // that redeclarations will match. 3345 QualType T = NewTD->getUnderlyingType(); 3346 if (T->isVariablyModifiedType()) { 3347 getCurFunction()->setHasBranchProtectedScope(); 3348 3349 if (S->getFnParent() == 0) { 3350 bool SizeIsNegative; 3351 llvm::APSInt Oversized; 3352 QualType FixedTy = 3353 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3354 Oversized); 3355 if (!FixedTy.isNull()) { 3356 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size); 3357 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 3358 } else { 3359 if (SizeIsNegative) 3360 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size); 3361 else if (T->isVariableArrayType()) 3362 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope); 3363 else if (Oversized.getBoolValue()) 3364 Diag(NewTD->getLocation(), diag::err_array_too_large) << Oversized.toString(10); 3365 else 3366 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope); 3367 NewTD->setInvalidDecl(); 3368 } 3369 } 3370 } 3371} 3372 3373 3374/// ActOnTypedefNameDecl - Perform semantic checking for a declaration which 3375/// declares a typedef-name, either using the 'typedef' type specifier or via 3376/// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'. 3377NamedDecl* 3378Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD, 3379 LookupResult &Previous, bool &Redeclaration) { 3380 // Merge the decl with the existing one if appropriate. If the decl is 3381 // in an outer scope, it isn't the same thing. 3382 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/ false, 3383 /*ExplicitInstantiationOrSpecialization=*/false); 3384 if (!Previous.empty()) { 3385 Redeclaration = true; 3386 MergeTypedefNameDecl(NewTD, Previous); 3387 } 3388 3389 // If this is the C FILE type, notify the AST context. 3390 if (IdentifierInfo *II = NewTD->getIdentifier()) 3391 if (!NewTD->isInvalidDecl() && 3392 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 3393 if (II->isStr("FILE")) 3394 Context.setFILEDecl(NewTD); 3395 else if (II->isStr("jmp_buf")) 3396 Context.setjmp_bufDecl(NewTD); 3397 else if (II->isStr("sigjmp_buf")) 3398 Context.setsigjmp_bufDecl(NewTD); 3399 else if (II->isStr("__builtin_va_list")) 3400 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 3401 } 3402 3403 return NewTD; 3404} 3405 3406/// \brief Determines whether the given declaration is an out-of-scope 3407/// previous declaration. 3408/// 3409/// This routine should be invoked when name lookup has found a 3410/// previous declaration (PrevDecl) that is not in the scope where a 3411/// new declaration by the same name is being introduced. If the new 3412/// declaration occurs in a local scope, previous declarations with 3413/// linkage may still be considered previous declarations (C99 3414/// 6.2.2p4-5, C++ [basic.link]p6). 3415/// 3416/// \param PrevDecl the previous declaration found by name 3417/// lookup 3418/// 3419/// \param DC the context in which the new declaration is being 3420/// declared. 3421/// 3422/// \returns true if PrevDecl is an out-of-scope previous declaration 3423/// for a new delcaration with the same name. 3424static bool 3425isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 3426 ASTContext &Context) { 3427 if (!PrevDecl) 3428 return false; 3429 3430 if (!PrevDecl->hasLinkage()) 3431 return false; 3432 3433 if (Context.getLangOptions().CPlusPlus) { 3434 // C++ [basic.link]p6: 3435 // If there is a visible declaration of an entity with linkage 3436 // having the same name and type, ignoring entities declared 3437 // outside the innermost enclosing namespace scope, the block 3438 // scope declaration declares that same entity and receives the 3439 // linkage of the previous declaration. 3440 DeclContext *OuterContext = DC->getRedeclContext(); 3441 if (!OuterContext->isFunctionOrMethod()) 3442 // This rule only applies to block-scope declarations. 3443 return false; 3444 3445 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 3446 if (PrevOuterContext->isRecord()) 3447 // We found a member function: ignore it. 3448 return false; 3449 3450 // Find the innermost enclosing namespace for the new and 3451 // previous declarations. 3452 OuterContext = OuterContext->getEnclosingNamespaceContext(); 3453 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 3454 3455 // The previous declaration is in a different namespace, so it 3456 // isn't the same function. 3457 if (!OuterContext->Equals(PrevOuterContext)) 3458 return false; 3459 } 3460 3461 return true; 3462} 3463 3464static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 3465 CXXScopeSpec &SS = D.getCXXScopeSpec(); 3466 if (!SS.isSet()) return; 3467 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 3468} 3469 3470NamedDecl* 3471Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 3472 QualType R, TypeSourceInfo *TInfo, 3473 LookupResult &Previous, 3474 MultiTemplateParamsArg TemplateParamLists, 3475 bool &Redeclaration) { 3476 DeclarationName Name = GetNameForDeclarator(D).getName(); 3477 3478 // Check that there are no default arguments (C++ only). 3479 if (getLangOptions().CPlusPlus) 3480 CheckExtraCXXDefaultArguments(D); 3481 3482 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 3483 assert(SCSpec != DeclSpec::SCS_typedef && 3484 "Parser allowed 'typedef' as storage class VarDecl."); 3485 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 3486 if (SCSpec == DeclSpec::SCS_mutable) { 3487 // mutable can only appear on non-static class members, so it's always 3488 // an error here 3489 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 3490 D.setInvalidType(); 3491 SC = SC_None; 3492 } 3493 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3494 VarDecl::StorageClass SCAsWritten 3495 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3496 3497 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3498 if (!II) { 3499 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3500 << Name.getAsString(); 3501 return 0; 3502 } 3503 3504 DiagnoseFunctionSpecifiers(D); 3505 3506 if (!DC->isRecord() && S->getFnParent() == 0) { 3507 // C99 6.9p2: The storage-class specifiers auto and register shall not 3508 // appear in the declaration specifiers in an external declaration. 3509 if (SC == SC_Auto || SC == SC_Register) { 3510 3511 // If this is a register variable with an asm label specified, then this 3512 // is a GNU extension. 3513 if (SC == SC_Register && D.getAsmLabel()) 3514 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3515 else 3516 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3517 D.setInvalidType(); 3518 } 3519 } 3520 3521 bool isExplicitSpecialization = false; 3522 VarDecl *NewVD; 3523 if (!getLangOptions().CPlusPlus) { 3524 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3525 D.getIdentifierLoc(), II, 3526 R, TInfo, SC, SCAsWritten); 3527 3528 if (D.isInvalidType()) 3529 NewVD->setInvalidDecl(); 3530 } else { 3531 if (DC->isRecord() && !CurContext->isRecord()) { 3532 // This is an out-of-line definition of a static data member. 3533 if (SC == SC_Static) { 3534 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3535 diag::err_static_out_of_line) 3536 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3537 } else if (SC == SC_None) 3538 SC = SC_Static; 3539 } 3540 if (SC == SC_Static) { 3541 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3542 if (RD->isLocalClass()) 3543 Diag(D.getIdentifierLoc(), 3544 diag::err_static_data_member_not_allowed_in_local_class) 3545 << Name << RD->getDeclName(); 3546 3547 // C++ [class.union]p1: If a union contains a static data member, 3548 // the program is ill-formed. 3549 // 3550 // We also disallow static data members in anonymous structs. 3551 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3552 Diag(D.getIdentifierLoc(), 3553 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3554 << Name << RD->isUnion(); 3555 } 3556 } 3557 3558 // Match up the template parameter lists with the scope specifier, then 3559 // determine whether we have a template or a template specialization. 3560 isExplicitSpecialization = false; 3561 bool Invalid = false; 3562 if (TemplateParameterList *TemplateParams 3563 = MatchTemplateParametersToScopeSpecifier( 3564 D.getDeclSpec().getSourceRange().getBegin(), 3565 D.getIdentifierLoc(), 3566 D.getCXXScopeSpec(), 3567 TemplateParamLists.get(), 3568 TemplateParamLists.size(), 3569 /*never a friend*/ false, 3570 isExplicitSpecialization, 3571 Invalid)) { 3572 if (TemplateParams->size() > 0) { 3573 // There is no such thing as a variable template. 3574 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3575 << II 3576 << SourceRange(TemplateParams->getTemplateLoc(), 3577 TemplateParams->getRAngleLoc()); 3578 return 0; 3579 } else { 3580 // There is an extraneous 'template<>' for this variable. Complain 3581 // about it, but allow the declaration of the variable. 3582 Diag(TemplateParams->getTemplateLoc(), 3583 diag::err_template_variable_noparams) 3584 << II 3585 << SourceRange(TemplateParams->getTemplateLoc(), 3586 TemplateParams->getRAngleLoc()); 3587 } 3588 } 3589 3590 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3591 D.getIdentifierLoc(), II, 3592 R, TInfo, SC, SCAsWritten); 3593 3594 // If this decl has an auto type in need of deduction, make a note of the 3595 // Decl so we can diagnose uses of it in its own initializer. 3596 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3597 R->getContainedAutoType()) 3598 ParsingInitForAutoVars.insert(NewVD); 3599 3600 if (D.isInvalidType() || Invalid) 3601 NewVD->setInvalidDecl(); 3602 3603 SetNestedNameSpecifier(NewVD, D); 3604 3605 if (TemplateParamLists.size() > 0 && D.getCXXScopeSpec().isSet()) { 3606 NewVD->setTemplateParameterListsInfo(Context, 3607 TemplateParamLists.size(), 3608 TemplateParamLists.release()); 3609 } 3610 } 3611 3612 if (D.getDeclSpec().isThreadSpecified()) { 3613 if (NewVD->hasLocalStorage()) 3614 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3615 else if (!Context.Target.isTLSSupported()) 3616 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3617 else 3618 NewVD->setThreadSpecified(true); 3619 } 3620 3621 // Set the lexical context. If the declarator has a C++ scope specifier, the 3622 // lexical context will be different from the semantic context. 3623 NewVD->setLexicalDeclContext(CurContext); 3624 3625 // Handle attributes prior to checking for duplicates in MergeVarDecl 3626 ProcessDeclAttributes(S, NewVD, D); 3627 3628 // Handle GNU asm-label extension (encoded as an attribute). 3629 if (Expr *E = (Expr*)D.getAsmLabel()) { 3630 // The parser guarantees this is a string. 3631 StringLiteral *SE = cast<StringLiteral>(E); 3632 llvm::StringRef Label = SE->getString(); 3633 if (S->getFnParent() != 0) { 3634 switch (SC) { 3635 case SC_None: 3636 case SC_Auto: 3637 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3638 break; 3639 case SC_Register: 3640 if (!Context.Target.isValidGCCRegisterName(Label)) 3641 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3642 break; 3643 case SC_Static: 3644 case SC_Extern: 3645 case SC_PrivateExtern: 3646 break; 3647 } 3648 } 3649 3650 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3651 Context, Label)); 3652 } 3653 3654 // Diagnose shadowed variables before filtering for scope. 3655 if (!D.getCXXScopeSpec().isSet()) 3656 CheckShadow(S, NewVD, Previous); 3657 3658 // Don't consider existing declarations that are in a different 3659 // scope and are out-of-semantic-context declarations (if the new 3660 // declaration has linkage). 3661 FilterLookupForScope(Previous, DC, S, NewVD->hasLinkage(), 3662 isExplicitSpecialization); 3663 3664 if (!getLangOptions().CPlusPlus) 3665 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3666 else { 3667 // Merge the decl with the existing one if appropriate. 3668 if (!Previous.empty()) { 3669 if (Previous.isSingleResult() && 3670 isa<FieldDecl>(Previous.getFoundDecl()) && 3671 D.getCXXScopeSpec().isSet()) { 3672 // The user tried to define a non-static data member 3673 // out-of-line (C++ [dcl.meaning]p1). 3674 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3675 << D.getCXXScopeSpec().getRange(); 3676 Previous.clear(); 3677 NewVD->setInvalidDecl(); 3678 } 3679 } else if (D.getCXXScopeSpec().isSet()) { 3680 // No previous declaration in the qualifying scope. 3681 Diag(D.getIdentifierLoc(), diag::err_no_member) 3682 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3683 << D.getCXXScopeSpec().getRange(); 3684 NewVD->setInvalidDecl(); 3685 } 3686 3687 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3688 3689 // This is an explicit specialization of a static data member. Check it. 3690 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3691 CheckMemberSpecialization(NewVD, Previous)) 3692 NewVD->setInvalidDecl(); 3693 } 3694 3695 // attributes declared post-definition are currently ignored 3696 // FIXME: This should be handled in attribute merging, not 3697 // here. 3698 if (Previous.isSingleResult()) { 3699 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3700 if (Def && (Def = Def->getDefinition()) && 3701 Def != NewVD && D.hasAttributes()) { 3702 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3703 Diag(Def->getLocation(), diag::note_previous_definition); 3704 } 3705 } 3706 3707 // If this is a locally-scoped extern C variable, update the map of 3708 // such variables. 3709 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3710 !NewVD->isInvalidDecl()) 3711 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3712 3713 // If there's a #pragma GCC visibility in scope, and this isn't a class 3714 // member, set the visibility of this variable. 3715 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3716 AddPushedVisibilityAttribute(NewVD); 3717 3718 MarkUnusedFileScopedDecl(NewVD); 3719 3720 return NewVD; 3721} 3722 3723/// \brief Diagnose variable or built-in function shadowing. Implements 3724/// -Wshadow. 3725/// 3726/// This method is called whenever a VarDecl is added to a "useful" 3727/// scope. 3728/// 3729/// \param S the scope in which the shadowing name is being declared 3730/// \param R the lookup of the name 3731/// 3732void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3733 // Return if warning is ignored. 3734 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3735 Diagnostic::Ignored) 3736 return; 3737 3738 // Don't diagnose declarations at file scope. 3739 if (D->hasGlobalStorage()) 3740 return; 3741 3742 DeclContext *NewDC = D->getDeclContext(); 3743 3744 // Only diagnose if we're shadowing an unambiguous field or variable. 3745 if (R.getResultKind() != LookupResult::Found) 3746 return; 3747 3748 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3749 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3750 return; 3751 3752 // Fields are not shadowed by variables in C++ static methods. 3753 if (isa<FieldDecl>(ShadowedDecl)) 3754 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3755 if (MD->isStatic()) 3756 return; 3757 3758 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3759 if (shadowedVar->isExternC()) { 3760 // For shadowing external vars, make sure that we point to the global 3761 // declaration, not a locally scoped extern declaration. 3762 for (VarDecl::redecl_iterator 3763 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3764 I != E; ++I) 3765 if (I->isFileVarDecl()) { 3766 ShadowedDecl = *I; 3767 break; 3768 } 3769 } 3770 3771 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3772 3773 // Only warn about certain kinds of shadowing for class members. 3774 if (NewDC && NewDC->isRecord()) { 3775 // In particular, don't warn about shadowing non-class members. 3776 if (!OldDC->isRecord()) 3777 return; 3778 3779 // TODO: should we warn about static data members shadowing 3780 // static data members from base classes? 3781 3782 // TODO: don't diagnose for inaccessible shadowed members. 3783 // This is hard to do perfectly because we might friend the 3784 // shadowing context, but that's just a false negative. 3785 } 3786 3787 // Determine what kind of declaration we're shadowing. 3788 unsigned Kind; 3789 if (isa<RecordDecl>(OldDC)) { 3790 if (isa<FieldDecl>(ShadowedDecl)) 3791 Kind = 3; // field 3792 else 3793 Kind = 2; // static data member 3794 } else if (OldDC->isFileContext()) 3795 Kind = 1; // global 3796 else 3797 Kind = 0; // local 3798 3799 DeclarationName Name = R.getLookupName(); 3800 3801 // Emit warning and note. 3802 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3803 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3804} 3805 3806/// \brief Check -Wshadow without the advantage of a previous lookup. 3807void Sema::CheckShadow(Scope *S, VarDecl *D) { 3808 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3809 Diagnostic::Ignored) 3810 return; 3811 3812 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3813 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3814 LookupName(R, S); 3815 CheckShadow(S, D, R); 3816} 3817 3818/// \brief Perform semantic checking on a newly-created variable 3819/// declaration. 3820/// 3821/// This routine performs all of the type-checking required for a 3822/// variable declaration once it has been built. It is used both to 3823/// check variables after they have been parsed and their declarators 3824/// have been translated into a declaration, and to check variables 3825/// that have been instantiated from a template. 3826/// 3827/// Sets NewVD->isInvalidDecl() if an error was encountered. 3828void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3829 LookupResult &Previous, 3830 bool &Redeclaration) { 3831 // If the decl is already known invalid, don't check it. 3832 if (NewVD->isInvalidDecl()) 3833 return; 3834 3835 QualType T = NewVD->getType(); 3836 3837 if (T->isObjCObjectType()) { 3838 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3839 return NewVD->setInvalidDecl(); 3840 } 3841 3842 // Emit an error if an address space was applied to decl with local storage. 3843 // This includes arrays of objects with address space qualifiers, but not 3844 // automatic variables that point to other address spaces. 3845 // ISO/IEC TR 18037 S5.1.2 3846 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3847 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3848 return NewVD->setInvalidDecl(); 3849 } 3850 3851 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3852 && !NewVD->hasAttr<BlocksAttr>()) 3853 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3854 3855 bool isVM = T->isVariablyModifiedType(); 3856 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3857 NewVD->hasAttr<BlocksAttr>()) 3858 getCurFunction()->setHasBranchProtectedScope(); 3859 3860 if ((isVM && NewVD->hasLinkage()) || 3861 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3862 bool SizeIsNegative; 3863 llvm::APSInt Oversized; 3864 QualType FixedTy = 3865 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3866 Oversized); 3867 3868 if (FixedTy.isNull() && T->isVariableArrayType()) { 3869 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3870 // FIXME: This won't give the correct result for 3871 // int a[10][n]; 3872 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3873 3874 if (NewVD->isFileVarDecl()) 3875 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3876 << SizeRange; 3877 else if (NewVD->getStorageClass() == SC_Static) 3878 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3879 << SizeRange; 3880 else 3881 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3882 << SizeRange; 3883 return NewVD->setInvalidDecl(); 3884 } 3885 3886 if (FixedTy.isNull()) { 3887 if (NewVD->isFileVarDecl()) 3888 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3889 else 3890 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3891 return NewVD->setInvalidDecl(); 3892 } 3893 3894 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3895 NewVD->setType(FixedTy); 3896 } 3897 3898 if (Previous.empty() && NewVD->isExternC()) { 3899 // Since we did not find anything by this name and we're declaring 3900 // an extern "C" variable, look for a non-visible extern "C" 3901 // declaration with the same name. 3902 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3903 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3904 if (Pos != LocallyScopedExternalDecls.end()) 3905 Previous.addDecl(Pos->second); 3906 } 3907 3908 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3909 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3910 << T; 3911 return NewVD->setInvalidDecl(); 3912 } 3913 3914 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3915 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3916 return NewVD->setInvalidDecl(); 3917 } 3918 3919 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3920 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3921 return NewVD->setInvalidDecl(); 3922 } 3923 3924 // Function pointers and references cannot have qualified function type, only 3925 // function pointer-to-members can do that. 3926 QualType Pointee; 3927 unsigned PtrOrRef = 0; 3928 if (const PointerType *Ptr = T->getAs<PointerType>()) 3929 Pointee = Ptr->getPointeeType(); 3930 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3931 Pointee = Ref->getPointeeType(); 3932 PtrOrRef = 1; 3933 } 3934 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3935 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3936 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3937 << PtrOrRef; 3938 return NewVD->setInvalidDecl(); 3939 } 3940 3941 if (!Previous.empty()) { 3942 Redeclaration = true; 3943 MergeVarDecl(NewVD, Previous); 3944 } 3945} 3946 3947/// \brief Data used with FindOverriddenMethod 3948struct FindOverriddenMethodData { 3949 Sema *S; 3950 CXXMethodDecl *Method; 3951}; 3952 3953/// \brief Member lookup function that determines whether a given C++ 3954/// method overrides a method in a base class, to be used with 3955/// CXXRecordDecl::lookupInBases(). 3956static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3957 CXXBasePath &Path, 3958 void *UserData) { 3959 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3960 3961 FindOverriddenMethodData *Data 3962 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3963 3964 DeclarationName Name = Data->Method->getDeclName(); 3965 3966 // FIXME: Do we care about other names here too? 3967 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3968 // We really want to find the base class destructor here. 3969 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3970 CanQualType CT = Data->S->Context.getCanonicalType(T); 3971 3972 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3973 } 3974 3975 for (Path.Decls = BaseRecord->lookup(Name); 3976 Path.Decls.first != Path.Decls.second; 3977 ++Path.Decls.first) { 3978 NamedDecl *D = *Path.Decls.first; 3979 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3980 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3981 return true; 3982 } 3983 } 3984 3985 return false; 3986} 3987 3988/// AddOverriddenMethods - See if a method overrides any in the base classes, 3989/// and if so, check that it's a valid override and remember it. 3990bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3991 // Look for virtual methods in base classes that this method might override. 3992 CXXBasePaths Paths; 3993 FindOverriddenMethodData Data; 3994 Data.Method = MD; 3995 Data.S = this; 3996 bool AddedAny = false; 3997 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3998 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3999 E = Paths.found_decls_end(); I != E; ++I) { 4000 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 4001 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 4002 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 4003 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 4004 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 4005 AddedAny = true; 4006 } 4007 } 4008 } 4009 } 4010 4011 return AddedAny; 4012} 4013 4014static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 4015 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 4016 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 4017 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 4018 assert(!Prev.isAmbiguous() && 4019 "Cannot have an ambiguity in previous-declaration lookup"); 4020 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 4021 Func != FuncEnd; ++Func) { 4022 if (isa<FunctionDecl>(*Func) && 4023 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 4024 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 4025 } 4026} 4027 4028NamedDecl* 4029Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 4030 QualType R, TypeSourceInfo *TInfo, 4031 LookupResult &Previous, 4032 MultiTemplateParamsArg TemplateParamLists, 4033 bool IsFunctionDefinition, bool &Redeclaration) { 4034 assert(R.getTypePtr()->isFunctionType()); 4035 4036 // TODO: consider using NameInfo for diagnostic. 4037 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 4038 DeclarationName Name = NameInfo.getName(); 4039 FunctionDecl::StorageClass SC = SC_None; 4040 switch (D.getDeclSpec().getStorageClassSpec()) { 4041 default: assert(0 && "Unknown storage class!"); 4042 case DeclSpec::SCS_auto: 4043 case DeclSpec::SCS_register: 4044 case DeclSpec::SCS_mutable: 4045 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4046 diag::err_typecheck_sclass_func); 4047 D.setInvalidType(); 4048 break; 4049 case DeclSpec::SCS_unspecified: SC = SC_None; break; 4050 case DeclSpec::SCS_extern: SC = SC_Extern; break; 4051 case DeclSpec::SCS_static: { 4052 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 4053 // C99 6.7.1p5: 4054 // The declaration of an identifier for a function that has 4055 // block scope shall have no explicit storage-class specifier 4056 // other than extern 4057 // See also (C++ [dcl.stc]p4). 4058 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4059 diag::err_static_block_func); 4060 SC = SC_None; 4061 } else 4062 SC = SC_Static; 4063 break; 4064 } 4065 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 4066 } 4067 4068 if (D.getDeclSpec().isThreadSpecified()) 4069 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4070 4071 // Do not allow returning a objc interface by-value. 4072 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 4073 Diag(D.getIdentifierLoc(), 4074 diag::err_object_cannot_be_passed_returned_by_value) << 0 4075 << R->getAs<FunctionType>()->getResultType(); 4076 D.setInvalidType(); 4077 } 4078 4079 FunctionDecl *NewFD; 4080 bool isInline = D.getDeclSpec().isInlineSpecified(); 4081 bool isFriend = false; 4082 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 4083 FunctionDecl::StorageClass SCAsWritten 4084 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 4085 FunctionTemplateDecl *FunctionTemplate = 0; 4086 bool isExplicitSpecialization = false; 4087 bool isFunctionTemplateSpecialization = false; 4088 4089 if (!getLangOptions().CPlusPlus) { 4090 // Determine whether the function was written with a 4091 // prototype. This true when: 4092 // - there is a prototype in the declarator, or 4093 // - the type R of the function is some kind of typedef or other reference 4094 // to a type name (which eventually refers to a function type). 4095 bool HasPrototype = 4096 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 4097 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 4098 4099 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4100 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 4101 HasPrototype); 4102 if (D.isInvalidType()) 4103 NewFD->setInvalidDecl(); 4104 4105 // Set the lexical context. 4106 NewFD->setLexicalDeclContext(CurContext); 4107 // Filter out previous declarations that don't match the scope. 4108 FilterLookupForScope(Previous, DC, S, NewFD->hasLinkage(), 4109 /*ExplicitInstantiationOrSpecialization=*/false); 4110 } else { 4111 isFriend = D.getDeclSpec().isFriendSpecified(); 4112 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 4113 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 4114 bool isVirtualOkay = false; 4115 4116 // Check that the return type is not an abstract class type. 4117 // For record types, this is done by the AbstractClassUsageDiagnoser once 4118 // the class has been completely parsed. 4119 if (!DC->isRecord() && 4120 RequireNonAbstractType(D.getIdentifierLoc(), 4121 R->getAs<FunctionType>()->getResultType(), 4122 diag::err_abstract_type_in_decl, 4123 AbstractReturnType)) 4124 D.setInvalidType(); 4125 4126 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 4127 // This is a C++ constructor declaration. 4128 assert(DC->isRecord() && 4129 "Constructors can only be declared in a member context"); 4130 4131 R = CheckConstructorDeclarator(D, R, SC); 4132 4133 // Create the new declaration 4134 CXXConstructorDecl *NewCD = CXXConstructorDecl::Create( 4135 Context, 4136 cast<CXXRecordDecl>(DC), 4137 D.getSourceRange().getBegin(), 4138 NameInfo, R, TInfo, 4139 isExplicit, isInline, 4140 /*isImplicitlyDeclared=*/false); 4141 4142 NewFD = NewCD; 4143 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4144 // This is a C++ destructor declaration. 4145 if (DC->isRecord()) { 4146 R = CheckDestructorDeclarator(D, R, SC); 4147 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 4148 4149 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(Context, Record, 4150 D.getSourceRange().getBegin(), 4151 NameInfo, R, TInfo, 4152 isInline, 4153 /*isImplicitlyDeclared=*/false); 4154 NewFD = NewDD; 4155 isVirtualOkay = true; 4156 4157 // If the class is complete, then we now create the implicit exception 4158 // specification. If the class is incomplete or dependent, we can't do 4159 // it yet. 4160 if (getLangOptions().CPlusPlus0x && !Record->isDependentType() && 4161 Record->getDefinition() && !Record->isBeingDefined() && 4162 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) { 4163 AdjustDestructorExceptionSpec(Record, NewDD); 4164 } 4165 4166 } else { 4167 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 4168 4169 // Create a FunctionDecl to satisfy the function definition parsing 4170 // code path. 4171 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4172 D.getIdentifierLoc(), Name, R, TInfo, 4173 SC, SCAsWritten, isInline, 4174 /*hasPrototype=*/true); 4175 D.setInvalidType(); 4176 } 4177 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 4178 if (!DC->isRecord()) { 4179 Diag(D.getIdentifierLoc(), 4180 diag::err_conv_function_not_member); 4181 return 0; 4182 } 4183 4184 CheckConversionDeclarator(D, R, SC); 4185 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 4186 D.getSourceRange().getBegin(), 4187 NameInfo, R, TInfo, 4188 isInline, isExplicit, 4189 SourceLocation()); 4190 4191 isVirtualOkay = true; 4192 } else if (DC->isRecord()) { 4193 // If the of the function is the same as the name of the record, then this 4194 // must be an invalid constructor that has a return type. 4195 // (The parser checks for a return type and makes the declarator a 4196 // constructor if it has no return type). 4197 // must have an invalid constructor that has a return type 4198 if (Name.getAsIdentifierInfo() && 4199 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 4200 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 4201 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 4202 << SourceRange(D.getIdentifierLoc()); 4203 return 0; 4204 } 4205 4206 bool isStatic = SC == SC_Static; 4207 4208 // [class.free]p1: 4209 // Any allocation function for a class T is a static member 4210 // (even if not explicitly declared static). 4211 if (Name.getCXXOverloadedOperator() == OO_New || 4212 Name.getCXXOverloadedOperator() == OO_Array_New) 4213 isStatic = true; 4214 4215 // [class.free]p6 Any deallocation function for a class X is a static member 4216 // (even if not explicitly declared static). 4217 if (Name.getCXXOverloadedOperator() == OO_Delete || 4218 Name.getCXXOverloadedOperator() == OO_Array_Delete) 4219 isStatic = true; 4220 4221 // This is a C++ method declaration. 4222 CXXMethodDecl *NewMD = CXXMethodDecl::Create( 4223 Context, cast<CXXRecordDecl>(DC), 4224 D.getSourceRange().getBegin(), 4225 NameInfo, R, TInfo, 4226 isStatic, SCAsWritten, isInline, 4227 SourceLocation()); 4228 NewFD = NewMD; 4229 4230 isVirtualOkay = !isStatic; 4231 } else { 4232 // Determine whether the function was written with a 4233 // prototype. This true when: 4234 // - we're in C++ (where every function has a prototype), 4235 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4236 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 4237 true/*HasPrototype*/); 4238 } 4239 4240 if (isFriend && !isInline && IsFunctionDefinition) { 4241 // C++ [class.friend]p5 4242 // A function can be defined in a friend declaration of a 4243 // class . . . . Such a function is implicitly inline. 4244 NewFD->setImplicitlyInline(); 4245 } 4246 4247 SetNestedNameSpecifier(NewFD, D); 4248 isExplicitSpecialization = false; 4249 isFunctionTemplateSpecialization = false; 4250 if (D.isInvalidType()) 4251 NewFD->setInvalidDecl(); 4252 4253 // Set the lexical context. If the declarator has a C++ 4254 // scope specifier, or is the object of a friend declaration, the 4255 // lexical context will be different from the semantic context. 4256 NewFD->setLexicalDeclContext(CurContext); 4257 4258 // Match up the template parameter lists with the scope specifier, then 4259 // determine whether we have a template or a template specialization. 4260 bool Invalid = false; 4261 if (TemplateParameterList *TemplateParams 4262 = MatchTemplateParametersToScopeSpecifier( 4263 D.getDeclSpec().getSourceRange().getBegin(), 4264 D.getIdentifierLoc(), 4265 D.getCXXScopeSpec(), 4266 TemplateParamLists.get(), 4267 TemplateParamLists.size(), 4268 isFriend, 4269 isExplicitSpecialization, 4270 Invalid)) { 4271 if (TemplateParams->size() > 0) { 4272 // This is a function template 4273 4274 // Check that we can declare a template here. 4275 if (CheckTemplateDeclScope(S, TemplateParams)) 4276 return 0; 4277 4278 // A destructor cannot be a template. 4279 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4280 Diag(NewFD->getLocation(), diag::err_destructor_template); 4281 return 0; 4282 } 4283 4284 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 4285 NewFD->getLocation(), 4286 Name, TemplateParams, 4287 NewFD); 4288 FunctionTemplate->setLexicalDeclContext(CurContext); 4289 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 4290 4291 // For source fidelity, store the other template param lists. 4292 if (TemplateParamLists.size() > 1) { 4293 NewFD->setTemplateParameterListsInfo(Context, 4294 TemplateParamLists.size() - 1, 4295 TemplateParamLists.release()); 4296 } 4297 } else { 4298 // This is a function template specialization. 4299 isFunctionTemplateSpecialization = true; 4300 // For source fidelity, store all the template param lists. 4301 NewFD->setTemplateParameterListsInfo(Context, 4302 TemplateParamLists.size(), 4303 TemplateParamLists.release()); 4304 4305 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 4306 if (isFriend) { 4307 // We want to remove the "template<>", found here. 4308 SourceRange RemoveRange = TemplateParams->getSourceRange(); 4309 4310 // If we remove the template<> and the name is not a 4311 // template-id, we're actually silently creating a problem: 4312 // the friend declaration will refer to an untemplated decl, 4313 // and clearly the user wants a template specialization. So 4314 // we need to insert '<>' after the name. 4315 SourceLocation InsertLoc; 4316 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 4317 InsertLoc = D.getName().getSourceRange().getEnd(); 4318 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 4319 } 4320 4321 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 4322 << Name << RemoveRange 4323 << FixItHint::CreateRemoval(RemoveRange) 4324 << FixItHint::CreateInsertion(InsertLoc, "<>"); 4325 } 4326 } 4327 } 4328 else { 4329 // All template param lists were matched against the scope specifier: 4330 // this is NOT (an explicit specialization of) a template. 4331 if (TemplateParamLists.size() > 0) 4332 // For source fidelity, store all the template param lists. 4333 NewFD->setTemplateParameterListsInfo(Context, 4334 TemplateParamLists.size(), 4335 TemplateParamLists.release()); 4336 } 4337 4338 if (Invalid) { 4339 NewFD->setInvalidDecl(); 4340 if (FunctionTemplate) 4341 FunctionTemplate->setInvalidDecl(); 4342 } 4343 4344 // C++ [dcl.fct.spec]p5: 4345 // The virtual specifier shall only be used in declarations of 4346 // nonstatic class member functions that appear within a 4347 // member-specification of a class declaration; see 10.3. 4348 // 4349 if (isVirtual && !NewFD->isInvalidDecl()) { 4350 if (!isVirtualOkay) { 4351 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4352 diag::err_virtual_non_function); 4353 } else if (!CurContext->isRecord()) { 4354 // 'virtual' was specified outside of the class. 4355 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4356 diag::err_virtual_out_of_class) 4357 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 4358 } else if (NewFD->getDescribedFunctionTemplate()) { 4359 // C++ [temp.mem]p3: 4360 // A member function template shall not be virtual. 4361 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4362 diag::err_virtual_member_function_template) 4363 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 4364 } else { 4365 // Okay: Add virtual to the method. 4366 NewFD->setVirtualAsWritten(true); 4367 } 4368 } 4369 4370 // C++ [dcl.fct.spec]p3: 4371 // The inline specifier shall not appear on a block scope function declaration. 4372 if (isInline && !NewFD->isInvalidDecl()) { 4373 if (CurContext->isFunctionOrMethod()) { 4374 // 'inline' is not allowed on block scope function declaration. 4375 Diag(D.getDeclSpec().getInlineSpecLoc(), 4376 diag::err_inline_declaration_block_scope) << Name 4377 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 4378 } 4379 } 4380 4381 // C++ [dcl.fct.spec]p6: 4382 // The explicit specifier shall be used only in the declaration of a 4383 // constructor or conversion function within its class definition; see 12.3.1 4384 // and 12.3.2. 4385 if (isExplicit && !NewFD->isInvalidDecl()) { 4386 if (!CurContext->isRecord()) { 4387 // 'explicit' was specified outside of the class. 4388 Diag(D.getDeclSpec().getExplicitSpecLoc(), 4389 diag::err_explicit_out_of_class) 4390 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 4391 } else if (!isa<CXXConstructorDecl>(NewFD) && 4392 !isa<CXXConversionDecl>(NewFD)) { 4393 // 'explicit' was specified on a function that wasn't a constructor 4394 // or conversion function. 4395 Diag(D.getDeclSpec().getExplicitSpecLoc(), 4396 diag::err_explicit_non_ctor_or_conv_function) 4397 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 4398 } 4399 } 4400 4401 // Filter out previous declarations that don't match the scope. 4402 FilterLookupForScope(Previous, DC, S, NewFD->hasLinkage(), 4403 isExplicitSpecialization || 4404 isFunctionTemplateSpecialization); 4405 4406 if (isFriend) { 4407 // For now, claim that the objects have no previous declaration. 4408 if (FunctionTemplate) { 4409 FunctionTemplate->setObjectOfFriendDecl(false); 4410 FunctionTemplate->setAccess(AS_public); 4411 } 4412 NewFD->setObjectOfFriendDecl(false); 4413 NewFD->setAccess(AS_public); 4414 } 4415 4416 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 4417 // A method is implicitly inline if it's defined in its class 4418 // definition. 4419 NewFD->setImplicitlyInline(); 4420 } 4421 4422 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 4423 !CurContext->isRecord()) { 4424 // C++ [class.static]p1: 4425 // A data or function member of a class may be declared static 4426 // in a class definition, in which case it is a static member of 4427 // the class. 4428 4429 // Complain about the 'static' specifier if it's on an out-of-line 4430 // member function definition. 4431 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4432 diag::err_static_out_of_line) 4433 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4434 } 4435 } 4436 4437 // Handle GNU asm-label extension (encoded as an attribute). 4438 if (Expr *E = (Expr*) D.getAsmLabel()) { 4439 // The parser guarantees this is a string. 4440 StringLiteral *SE = cast<StringLiteral>(E); 4441 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 4442 SE->getString())); 4443 } 4444 4445 // Copy the parameter declarations from the declarator D to the function 4446 // declaration NewFD, if they are available. First scavenge them into Params. 4447 llvm::SmallVector<ParmVarDecl*, 16> Params; 4448 if (D.isFunctionDeclarator()) { 4449 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 4450 4451 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 4452 // function that takes no arguments, not a function that takes a 4453 // single void argument. 4454 // We let through "const void" here because Sema::GetTypeForDeclarator 4455 // already checks for that case. 4456 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4457 FTI.ArgInfo[0].Param && 4458 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 4459 // Empty arg list, don't push any params. 4460 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 4461 4462 // In C++, the empty parameter-type-list must be spelled "void"; a 4463 // typedef of void is not permitted. 4464 if (getLangOptions().CPlusPlus && 4465 Param->getType().getUnqualifiedType() != Context.VoidTy) { 4466 bool IsTypeAlias = false; 4467 if (const TypedefType *TT = Param->getType()->getAs<TypedefType>()) 4468 IsTypeAlias = isa<TypeAliasDecl>(TT->getDecl()); 4469 else if (const TemplateSpecializationType *TST = 4470 Param->getType()->getAs<TemplateSpecializationType>()) 4471 IsTypeAlias = TST->isTypeAlias(); 4472 Diag(Param->getLocation(), diag::err_param_typedef_of_void) 4473 << IsTypeAlias; 4474 } 4475 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 4476 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 4477 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 4478 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 4479 Param->setDeclContext(NewFD); 4480 Params.push_back(Param); 4481 4482 if (Param->isInvalidDecl()) 4483 NewFD->setInvalidDecl(); 4484 } 4485 } 4486 4487 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 4488 // When we're declaring a function with a typedef, typeof, etc as in the 4489 // following example, we'll need to synthesize (unnamed) 4490 // parameters for use in the declaration. 4491 // 4492 // @code 4493 // typedef void fn(int); 4494 // fn f; 4495 // @endcode 4496 4497 // Synthesize a parameter for each argument type. 4498 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 4499 AE = FT->arg_type_end(); AI != AE; ++AI) { 4500 ParmVarDecl *Param = 4501 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 4502 Param->setScopeInfo(0, Params.size()); 4503 Params.push_back(Param); 4504 } 4505 } else { 4506 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 4507 "Should not need args for typedef of non-prototype fn"); 4508 } 4509 // Finally, we know we have the right number of parameters, install them. 4510 NewFD->setParams(Params.data(), Params.size()); 4511 4512 // Process the non-inheritable attributes on this declaration. 4513 ProcessDeclAttributes(S, NewFD, D, 4514 /*NonInheritable=*/true, /*Inheritable=*/false); 4515 4516 if (!getLangOptions().CPlusPlus) { 4517 // Perform semantic checking on the function declaration. 4518 bool isExplctSpecialization=false; 4519 CheckFunctionDeclaration(S, NewFD, Previous, isExplctSpecialization, 4520 Redeclaration); 4521 assert((NewFD->isInvalidDecl() || !Redeclaration || 4522 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4523 "previous declaration set still overloaded"); 4524 } else { 4525 // If the declarator is a template-id, translate the parser's template 4526 // argument list into our AST format. 4527 bool HasExplicitTemplateArgs = false; 4528 TemplateArgumentListInfo TemplateArgs; 4529 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4530 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4531 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4532 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4533 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4534 TemplateId->getTemplateArgs(), 4535 TemplateId->NumArgs); 4536 translateTemplateArguments(TemplateArgsPtr, 4537 TemplateArgs); 4538 TemplateArgsPtr.release(); 4539 4540 HasExplicitTemplateArgs = true; 4541 4542 if (FunctionTemplate) { 4543 // Function template with explicit template arguments. 4544 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4545 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4546 4547 HasExplicitTemplateArgs = false; 4548 } else if (!isFunctionTemplateSpecialization && 4549 !D.getDeclSpec().isFriendSpecified()) { 4550 // We have encountered something that the user meant to be a 4551 // specialization (because it has explicitly-specified template 4552 // arguments) but that was not introduced with a "template<>" (or had 4553 // too few of them). 4554 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4555 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4556 << FixItHint::CreateInsertion( 4557 D.getDeclSpec().getSourceRange().getBegin(), 4558 "template<> "); 4559 isFunctionTemplateSpecialization = true; 4560 } else { 4561 // "friend void foo<>(int);" is an implicit specialization decl. 4562 isFunctionTemplateSpecialization = true; 4563 } 4564 } else if (isFriend && isFunctionTemplateSpecialization) { 4565 // This combination is only possible in a recovery case; the user 4566 // wrote something like: 4567 // template <> friend void foo(int); 4568 // which we're recovering from as if the user had written: 4569 // friend void foo<>(int); 4570 // Go ahead and fake up a template id. 4571 HasExplicitTemplateArgs = true; 4572 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4573 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4574 } 4575 4576 // If it's a friend (and only if it's a friend), it's possible 4577 // that either the specialized function type or the specialized 4578 // template is dependent, and therefore matching will fail. In 4579 // this case, don't check the specialization yet. 4580 if (isFunctionTemplateSpecialization && isFriend && 4581 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4582 assert(HasExplicitTemplateArgs && 4583 "friend function specialization without template args"); 4584 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4585 Previous)) 4586 NewFD->setInvalidDecl(); 4587 } else if (isFunctionTemplateSpecialization) { 4588 if (CurContext->isDependentContext() && CurContext->isRecord() 4589 && !isFriend && !getLangOptions().Microsoft) { 4590 Diag(NewFD->getLocation(), diag::err_function_specialization_in_class) 4591 << NewFD->getDeclName(); 4592 NewFD->setInvalidDecl(); 4593 return 0; 4594 } else if (CheckFunctionTemplateSpecialization(NewFD, 4595 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4596 Previous)) 4597 NewFD->setInvalidDecl(); 4598 4599 // C++ [dcl.stc]p1: 4600 // A storage-class-specifier shall not be specified in an explicit 4601 // specialization (14.7.3) 4602 if (SC != SC_None) { 4603 Diag(NewFD->getLocation(), 4604 diag::err_explicit_specialization_storage_class) 4605 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4606 } 4607 4608 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4609 if (CheckMemberSpecialization(NewFD, Previous)) 4610 NewFD->setInvalidDecl(); 4611 } 4612 4613 // Perform semantic checking on the function declaration. 4614 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4615 Redeclaration); 4616 4617 assert((NewFD->isInvalidDecl() || !Redeclaration || 4618 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4619 "previous declaration set still overloaded"); 4620 4621 NamedDecl *PrincipalDecl = (FunctionTemplate 4622 ? cast<NamedDecl>(FunctionTemplate) 4623 : NewFD); 4624 4625 if (isFriend && Redeclaration) { 4626 AccessSpecifier Access = AS_public; 4627 if (!NewFD->isInvalidDecl()) 4628 Access = NewFD->getPreviousDeclaration()->getAccess(); 4629 4630 NewFD->setAccess(Access); 4631 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4632 4633 PrincipalDecl->setObjectOfFriendDecl(true); 4634 } 4635 4636 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4637 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4638 PrincipalDecl->setNonMemberOperator(); 4639 4640 // If we have a function template, check the template parameter 4641 // list. This will check and merge default template arguments. 4642 if (FunctionTemplate) { 4643 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4644 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4645 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4646 D.getDeclSpec().isFriendSpecified() 4647 ? (IsFunctionDefinition 4648 ? TPC_FriendFunctionTemplateDefinition 4649 : TPC_FriendFunctionTemplate) 4650 : (D.getCXXScopeSpec().isSet() && 4651 DC && DC->isRecord() && 4652 DC->isDependentContext()) 4653 ? TPC_ClassTemplateMember 4654 : TPC_FunctionTemplate); 4655 } 4656 4657 if (NewFD->isInvalidDecl()) { 4658 // Ignore all the rest of this. 4659 } else if (!Redeclaration) { 4660 // Fake up an access specifier if it's supposed to be a class member. 4661 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4662 NewFD->setAccess(AS_public); 4663 4664 // Qualified decls generally require a previous declaration. 4665 if (D.getCXXScopeSpec().isSet()) { 4666 // ...with the major exception of templated-scope or 4667 // dependent-scope friend declarations. 4668 4669 // TODO: we currently also suppress this check in dependent 4670 // contexts because (1) the parameter depth will be off when 4671 // matching friend templates and (2) we might actually be 4672 // selecting a friend based on a dependent factor. But there 4673 // are situations where these conditions don't apply and we 4674 // can actually do this check immediately. 4675 if (isFriend && 4676 (TemplateParamLists.size() || 4677 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4678 CurContext->isDependentContext())) { 4679 // ignore these 4680 } else { 4681 // The user tried to provide an out-of-line definition for a 4682 // function that is a member of a class or namespace, but there 4683 // was no such member function declared (C++ [class.mfct]p2, 4684 // C++ [namespace.memdef]p2). For example: 4685 // 4686 // class X { 4687 // void f() const; 4688 // }; 4689 // 4690 // void X::f() { } // ill-formed 4691 // 4692 // Complain about this problem, and attempt to suggest close 4693 // matches (e.g., those that differ only in cv-qualifiers and 4694 // whether the parameter types are references). 4695 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4696 << Name << DC << D.getCXXScopeSpec().getRange(); 4697 NewFD->setInvalidDecl(); 4698 4699 DiagnoseInvalidRedeclaration(*this, NewFD); 4700 } 4701 4702 // Unqualified local friend declarations are required to resolve 4703 // to something. 4704 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4705 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4706 NewFD->setInvalidDecl(); 4707 DiagnoseInvalidRedeclaration(*this, NewFD); 4708 } 4709 4710 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4711 !isFriend && !isFunctionTemplateSpecialization && 4712 !isExplicitSpecialization) { 4713 // An out-of-line member function declaration must also be a 4714 // definition (C++ [dcl.meaning]p1). 4715 // Note that this is not the case for explicit specializations of 4716 // function templates or member functions of class templates, per 4717 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4718 // for compatibility with old SWIG code which likes to generate them. 4719 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4720 << D.getCXXScopeSpec().getRange(); 4721 } 4722 } 4723 4724 4725 // Handle attributes. We need to have merged decls when handling attributes 4726 // (for example to check for conflicts, etc). 4727 // FIXME: This needs to happen before we merge declarations. Then, 4728 // let attribute merging cope with attribute conflicts. 4729 ProcessDeclAttributes(S, NewFD, D, 4730 /*NonInheritable=*/false, /*Inheritable=*/true); 4731 4732 // attributes declared post-definition are currently ignored 4733 // FIXME: This should happen during attribute merging 4734 if (Redeclaration && Previous.isSingleResult()) { 4735 const FunctionDecl *Def; 4736 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4737 if (PrevFD && PrevFD->isDefined(Def) && D.hasAttributes()) { 4738 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4739 Diag(Def->getLocation(), diag::note_previous_definition); 4740 } 4741 } 4742 4743 AddKnownFunctionAttributes(NewFD); 4744 4745 if (NewFD->hasAttr<OverloadableAttr>() && 4746 !NewFD->getType()->getAs<FunctionProtoType>()) { 4747 Diag(NewFD->getLocation(), 4748 diag::err_attribute_overloadable_no_prototype) 4749 << NewFD; 4750 4751 // Turn this into a variadic function with no parameters. 4752 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4753 FunctionProtoType::ExtProtoInfo EPI; 4754 EPI.Variadic = true; 4755 EPI.ExtInfo = FT->getExtInfo(); 4756 4757 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4758 NewFD->setType(R); 4759 } 4760 4761 // If there's a #pragma GCC visibility in scope, and this isn't a class 4762 // member, set the visibility of this function. 4763 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4764 AddPushedVisibilityAttribute(NewFD); 4765 4766 // If this is a locally-scoped extern C function, update the 4767 // map of such names. 4768 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4769 && !NewFD->isInvalidDecl()) 4770 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4771 4772 // Set this FunctionDecl's range up to the right paren. 4773 NewFD->setRangeEnd(D.getSourceRange().getEnd()); 4774 4775 if (getLangOptions().CPlusPlus) { 4776 if (FunctionTemplate) { 4777 if (NewFD->isInvalidDecl()) 4778 FunctionTemplate->setInvalidDecl(); 4779 return FunctionTemplate; 4780 } 4781 } 4782 4783 MarkUnusedFileScopedDecl(NewFD); 4784 4785 if (getLangOptions().CUDA) 4786 if (IdentifierInfo *II = NewFD->getIdentifier()) 4787 if (!NewFD->isInvalidDecl() && 4788 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4789 if (II->isStr("cudaConfigureCall")) { 4790 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4791 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4792 4793 Context.setcudaConfigureCallDecl(NewFD); 4794 } 4795 } 4796 4797 return NewFD; 4798} 4799 4800/// \brief Perform semantic checking of a new function declaration. 4801/// 4802/// Performs semantic analysis of the new function declaration 4803/// NewFD. This routine performs all semantic checking that does not 4804/// require the actual declarator involved in the declaration, and is 4805/// used both for the declaration of functions as they are parsed 4806/// (called via ActOnDeclarator) and for the declaration of functions 4807/// that have been instantiated via C++ template instantiation (called 4808/// via InstantiateDecl). 4809/// 4810/// \param IsExplicitSpecialiation whether this new function declaration is 4811/// an explicit specialization of the previous declaration. 4812/// 4813/// This sets NewFD->isInvalidDecl() to true if there was an error. 4814void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4815 LookupResult &Previous, 4816 bool IsExplicitSpecialization, 4817 bool &Redeclaration) { 4818 // If NewFD is already known erroneous, don't do any of this checking. 4819 if (NewFD->isInvalidDecl()) { 4820 // If this is a class member, mark the class invalid immediately. 4821 // This avoids some consistency errors later. 4822 if (isa<CXXMethodDecl>(NewFD)) 4823 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4824 4825 return; 4826 } 4827 4828 if (NewFD->getResultType()->isVariablyModifiedType()) { 4829 // Functions returning a variably modified type violate C99 6.7.5.2p2 4830 // because all functions have linkage. 4831 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4832 return NewFD->setInvalidDecl(); 4833 } 4834 4835 if (NewFD->isMain()) 4836 CheckMain(NewFD); 4837 4838 // Check for a previous declaration of this name. 4839 if (Previous.empty() && NewFD->isExternC()) { 4840 // Since we did not find anything by this name and we're declaring 4841 // an extern "C" function, look for a non-visible extern "C" 4842 // declaration with the same name. 4843 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4844 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4845 if (Pos != LocallyScopedExternalDecls.end()) 4846 Previous.addDecl(Pos->second); 4847 } 4848 4849 // Merge or overload the declaration with an existing declaration of 4850 // the same name, if appropriate. 4851 if (!Previous.empty()) { 4852 // Determine whether NewFD is an overload of PrevDecl or 4853 // a declaration that requires merging. If it's an overload, 4854 // there's no more work to do here; we'll just add the new 4855 // function to the scope. 4856 4857 NamedDecl *OldDecl = 0; 4858 if (!AllowOverloadingOfFunction(Previous, Context)) { 4859 Redeclaration = true; 4860 OldDecl = Previous.getFoundDecl(); 4861 } else { 4862 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4863 /*NewIsUsingDecl*/ false)) { 4864 case Ovl_Match: 4865 Redeclaration = true; 4866 break; 4867 4868 case Ovl_NonFunction: 4869 Redeclaration = true; 4870 break; 4871 4872 case Ovl_Overload: 4873 Redeclaration = false; 4874 break; 4875 } 4876 4877 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4878 // If a function name is overloadable in C, then every function 4879 // with that name must be marked "overloadable". 4880 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4881 << Redeclaration << NewFD; 4882 NamedDecl *OverloadedDecl = 0; 4883 if (Redeclaration) 4884 OverloadedDecl = OldDecl; 4885 else if (!Previous.empty()) 4886 OverloadedDecl = Previous.getRepresentativeDecl(); 4887 if (OverloadedDecl) 4888 Diag(OverloadedDecl->getLocation(), 4889 diag::note_attribute_overloadable_prev_overload); 4890 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4891 Context)); 4892 } 4893 } 4894 4895 if (Redeclaration) { 4896 // NewFD and OldDecl represent declarations that need to be 4897 // merged. 4898 if (MergeFunctionDecl(NewFD, OldDecl)) 4899 return NewFD->setInvalidDecl(); 4900 4901 Previous.clear(); 4902 Previous.addDecl(OldDecl); 4903 4904 if (FunctionTemplateDecl *OldTemplateDecl 4905 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4906 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4907 FunctionTemplateDecl *NewTemplateDecl 4908 = NewFD->getDescribedFunctionTemplate(); 4909 assert(NewTemplateDecl && "Template/non-template mismatch"); 4910 if (CXXMethodDecl *Method 4911 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4912 Method->setAccess(OldTemplateDecl->getAccess()); 4913 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4914 } 4915 4916 // If this is an explicit specialization of a member that is a function 4917 // template, mark it as a member specialization. 4918 if (IsExplicitSpecialization && 4919 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4920 NewTemplateDecl->setMemberSpecialization(); 4921 assert(OldTemplateDecl->isMemberSpecialization()); 4922 } 4923 } else { 4924 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4925 NewFD->setAccess(OldDecl->getAccess()); 4926 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4927 } 4928 } 4929 } 4930 4931 // Semantic checking for this function declaration (in isolation). 4932 if (getLangOptions().CPlusPlus) { 4933 // C++-specific checks. 4934 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4935 CheckConstructor(Constructor); 4936 } else if (CXXDestructorDecl *Destructor = 4937 dyn_cast<CXXDestructorDecl>(NewFD)) { 4938 CXXRecordDecl *Record = Destructor->getParent(); 4939 QualType ClassType = Context.getTypeDeclType(Record); 4940 4941 // FIXME: Shouldn't we be able to perform this check even when the class 4942 // type is dependent? Both gcc and edg can handle that. 4943 if (!ClassType->isDependentType()) { 4944 DeclarationName Name 4945 = Context.DeclarationNames.getCXXDestructorName( 4946 Context.getCanonicalType(ClassType)); 4947 if (NewFD->getDeclName() != Name) { 4948 Diag(NewFD->getLocation(), diag::err_destructor_name); 4949 return NewFD->setInvalidDecl(); 4950 } 4951 } 4952 } else if (CXXConversionDecl *Conversion 4953 = dyn_cast<CXXConversionDecl>(NewFD)) { 4954 ActOnConversionDeclarator(Conversion); 4955 } 4956 4957 // Find any virtual functions that this function overrides. 4958 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4959 if (!Method->isFunctionTemplateSpecialization() && 4960 !Method->getDescribedFunctionTemplate()) { 4961 if (AddOverriddenMethods(Method->getParent(), Method)) { 4962 // If the function was marked as "static", we have a problem. 4963 if (NewFD->getStorageClass() == SC_Static) { 4964 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4965 << NewFD->getDeclName(); 4966 for (CXXMethodDecl::method_iterator 4967 Overridden = Method->begin_overridden_methods(), 4968 OverriddenEnd = Method->end_overridden_methods(); 4969 Overridden != OverriddenEnd; 4970 ++Overridden) { 4971 Diag((*Overridden)->getLocation(), 4972 diag::note_overridden_virtual_function); 4973 } 4974 } 4975 } 4976 } 4977 } 4978 4979 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4980 if (NewFD->isOverloadedOperator() && 4981 CheckOverloadedOperatorDeclaration(NewFD)) 4982 return NewFD->setInvalidDecl(); 4983 4984 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4985 if (NewFD->getLiteralIdentifier() && 4986 CheckLiteralOperatorDeclaration(NewFD)) 4987 return NewFD->setInvalidDecl(); 4988 4989 // In C++, check default arguments now that we have merged decls. Unless 4990 // the lexical context is the class, because in this case this is done 4991 // during delayed parsing anyway. 4992 if (!CurContext->isRecord()) 4993 CheckCXXDefaultArguments(NewFD); 4994 4995 // If this function declares a builtin function, check the type of this 4996 // declaration against the expected type for the builtin. 4997 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 4998 ASTContext::GetBuiltinTypeError Error; 4999 QualType T = Context.GetBuiltinType(BuiltinID, Error); 5000 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 5001 // The type of this function differs from the type of the builtin, 5002 // so forget about the builtin entirely. 5003 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 5004 } 5005 } 5006 } 5007} 5008 5009void Sema::CheckMain(FunctionDecl* FD) { 5010 // C++ [basic.start.main]p3: A program that declares main to be inline 5011 // or static is ill-formed. 5012 // C99 6.7.4p4: In a hosted environment, the inline function specifier 5013 // shall not appear in a declaration of main. 5014 // static main is not an error under C99, but we should warn about it. 5015 bool isInline = FD->isInlineSpecified(); 5016 bool isStatic = FD->getStorageClass() == SC_Static; 5017 if (isInline || isStatic) { 5018 unsigned diagID = diag::warn_unusual_main_decl; 5019 if (isInline || getLangOptions().CPlusPlus) 5020 diagID = diag::err_unusual_main_decl; 5021 5022 int which = isStatic + (isInline << 1) - 1; 5023 Diag(FD->getLocation(), diagID) << which; 5024 } 5025 5026 QualType T = FD->getType(); 5027 assert(T->isFunctionType() && "function decl is not of function type"); 5028 const FunctionType* FT = T->getAs<FunctionType>(); 5029 5030 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 5031 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 5032 FD->setInvalidDecl(true); 5033 } 5034 5035 // Treat protoless main() as nullary. 5036 if (isa<FunctionNoProtoType>(FT)) return; 5037 5038 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 5039 unsigned nparams = FTP->getNumArgs(); 5040 assert(FD->getNumParams() == nparams); 5041 5042 bool HasExtraParameters = (nparams > 3); 5043 5044 // Darwin passes an undocumented fourth argument of type char**. If 5045 // other platforms start sprouting these, the logic below will start 5046 // getting shifty. 5047 if (nparams == 4 && Context.Target.getTriple().isOSDarwin()) 5048 HasExtraParameters = false; 5049 5050 if (HasExtraParameters) { 5051 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 5052 FD->setInvalidDecl(true); 5053 nparams = 3; 5054 } 5055 5056 // FIXME: a lot of the following diagnostics would be improved 5057 // if we had some location information about types. 5058 5059 QualType CharPP = 5060 Context.getPointerType(Context.getPointerType(Context.CharTy)); 5061 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 5062 5063 for (unsigned i = 0; i < nparams; ++i) { 5064 QualType AT = FTP->getArgType(i); 5065 5066 bool mismatch = true; 5067 5068 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 5069 mismatch = false; 5070 else if (Expected[i] == CharPP) { 5071 // As an extension, the following forms are okay: 5072 // char const ** 5073 // char const * const * 5074 // char * const * 5075 5076 QualifierCollector qs; 5077 const PointerType* PT; 5078 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 5079 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 5080 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 5081 qs.removeConst(); 5082 mismatch = !qs.empty(); 5083 } 5084 } 5085 5086 if (mismatch) { 5087 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 5088 // TODO: suggest replacing given type with expected type 5089 FD->setInvalidDecl(true); 5090 } 5091 } 5092 5093 if (nparams == 1 && !FD->isInvalidDecl()) { 5094 Diag(FD->getLocation(), diag::warn_main_one_arg); 5095 } 5096 5097 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 5098 Diag(FD->getLocation(), diag::err_main_template_decl); 5099 FD->setInvalidDecl(); 5100 } 5101} 5102 5103bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 5104 // FIXME: Need strict checking. In C89, we need to check for 5105 // any assignment, increment, decrement, function-calls, or 5106 // commas outside of a sizeof. In C99, it's the same list, 5107 // except that the aforementioned are allowed in unevaluated 5108 // expressions. Everything else falls under the 5109 // "may accept other forms of constant expressions" exception. 5110 // (We never end up here for C++, so the constant expression 5111 // rules there don't matter.) 5112 if (Init->isConstantInitializer(Context, false)) 5113 return false; 5114 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 5115 << Init->getSourceRange(); 5116 return true; 5117} 5118 5119namespace { 5120 // Visits an initialization expression to see if OrigDecl is evaluated in 5121 // its own initialization and throws a warning if it does. 5122 class SelfReferenceChecker 5123 : public EvaluatedExprVisitor<SelfReferenceChecker> { 5124 Sema &S; 5125 Decl *OrigDecl; 5126 5127 public: 5128 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited; 5129 5130 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context), 5131 S(S), OrigDecl(OrigDecl) { } 5132 5133 void VisitExpr(Expr *E) { 5134 if (isa<ObjCMessageExpr>(*E)) return; 5135 Inherited::VisitExpr(E); 5136 } 5137 5138 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 5139 CheckForSelfReference(E); 5140 Inherited::VisitImplicitCastExpr(E); 5141 } 5142 5143 void CheckForSelfReference(ImplicitCastExpr *E) { 5144 if (E->getCastKind() != CK_LValueToRValue) return; 5145 Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts(); 5146 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr); 5147 if (!DRE) return; 5148 Decl* ReferenceDecl = DRE->getDecl(); 5149 if (OrigDecl != ReferenceDecl) return; 5150 LookupResult Result(S, DRE->getNameInfo(), Sema::LookupOrdinaryName, 5151 Sema::NotForRedeclaration); 5152 S.Diag(SubExpr->getLocStart(), diag::warn_uninit_self_reference_in_init) 5153 << Result.getLookupName() << OrigDecl->getLocation() 5154 << SubExpr->getSourceRange(); 5155 } 5156 }; 5157} 5158 5159/// AddInitializerToDecl - Adds the initializer Init to the 5160/// declaration dcl. If DirectInit is true, this is C++ direct 5161/// initialization rather than copy initialization. 5162void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 5163 bool DirectInit, bool TypeMayContainAuto) { 5164 // If there is no declaration, there was an error parsing it. Just ignore 5165 // the initializer. 5166 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 5167 return; 5168 5169 // Check for self-references within variable initializers. 5170 if (VarDecl *vd = dyn_cast<VarDecl>(RealDecl)) { 5171 // Variables declared within a function/method body are handled 5172 // by a dataflow analysis. 5173 if (!vd->hasLocalStorage() && !vd->isStaticLocal()) 5174 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 5175 } 5176 else { 5177 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 5178 } 5179 5180 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 5181 // With declarators parsed the way they are, the parser cannot 5182 // distinguish between a normal initializer and a pure-specifier. 5183 // Thus this grotesque test. 5184 IntegerLiteral *IL; 5185 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 5186 Context.getCanonicalType(IL->getType()) == Context.IntTy) 5187 CheckPureMethod(Method, Init->getSourceRange()); 5188 else { 5189 Diag(Method->getLocation(), diag::err_member_function_initialization) 5190 << Method->getDeclName() << Init->getSourceRange(); 5191 Method->setInvalidDecl(); 5192 } 5193 return; 5194 } 5195 5196 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 5197 if (!VDecl) { 5198 if (getLangOptions().CPlusPlus && 5199 RealDecl->getLexicalDeclContext()->isRecord() && 5200 isa<NamedDecl>(RealDecl)) 5201 Diag(RealDecl->getLocation(), diag::err_member_initialization); 5202 else 5203 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 5204 RealDecl->setInvalidDecl(); 5205 return; 5206 } 5207 5208 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 5209 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 5210 TypeSourceInfo *DeducedType = 0; 5211 if (!DeduceAutoType(VDecl->getTypeSourceInfo(), Init, DeducedType)) 5212 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 5213 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 5214 << Init->getSourceRange(); 5215 if (!DeducedType) { 5216 RealDecl->setInvalidDecl(); 5217 return; 5218 } 5219 VDecl->setTypeSourceInfo(DeducedType); 5220 VDecl->setType(DeducedType->getType()); 5221 5222 // If this is a redeclaration, check that the type we just deduced matches 5223 // the previously declared type. 5224 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 5225 MergeVarDeclTypes(VDecl, Old); 5226 } 5227 5228 5229 // A definition must end up with a complete type, which means it must be 5230 // complete with the restriction that an array type might be completed by the 5231 // initializer; note that later code assumes this restriction. 5232 QualType BaseDeclType = VDecl->getType(); 5233 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 5234 BaseDeclType = Array->getElementType(); 5235 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 5236 diag::err_typecheck_decl_incomplete_type)) { 5237 RealDecl->setInvalidDecl(); 5238 return; 5239 } 5240 5241 // The variable can not have an abstract class type. 5242 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 5243 diag::err_abstract_type_in_decl, 5244 AbstractVariableType)) 5245 VDecl->setInvalidDecl(); 5246 5247 const VarDecl *Def; 5248 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 5249 Diag(VDecl->getLocation(), diag::err_redefinition) 5250 << VDecl->getDeclName(); 5251 Diag(Def->getLocation(), diag::note_previous_definition); 5252 VDecl->setInvalidDecl(); 5253 return; 5254 } 5255 5256 const VarDecl* PrevInit = 0; 5257 if (getLangOptions().CPlusPlus) { 5258 // C++ [class.static.data]p4 5259 // If a static data member is of const integral or const 5260 // enumeration type, its declaration in the class definition can 5261 // specify a constant-initializer which shall be an integral 5262 // constant expression (5.19). In that case, the member can appear 5263 // in integral constant expressions. The member shall still be 5264 // defined in a namespace scope if it is used in the program and the 5265 // namespace scope definition shall not contain an initializer. 5266 // 5267 // We already performed a redefinition check above, but for static 5268 // data members we also need to check whether there was an in-class 5269 // declaration with an initializer. 5270 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 5271 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 5272 Diag(PrevInit->getLocation(), diag::note_previous_definition); 5273 return; 5274 } 5275 5276 if (VDecl->hasLocalStorage()) 5277 getCurFunction()->setHasBranchProtectedScope(); 5278 5279 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 5280 VDecl->setInvalidDecl(); 5281 return; 5282 } 5283 } 5284 5285 // Capture the variable that is being initialized and the style of 5286 // initialization. 5287 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 5288 5289 // FIXME: Poor source location information. 5290 InitializationKind Kind 5291 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 5292 Init->getLocStart(), 5293 Init->getLocEnd()) 5294 : InitializationKind::CreateCopy(VDecl->getLocation(), 5295 Init->getLocStart()); 5296 5297 // Get the decls type and save a reference for later, since 5298 // CheckInitializerTypes may change it. 5299 QualType DclT = VDecl->getType(), SavT = DclT; 5300 if (VDecl->isLocalVarDecl()) { 5301 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 5302 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 5303 VDecl->setInvalidDecl(); 5304 } else if (!VDecl->isInvalidDecl()) { 5305 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5306 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5307 MultiExprArg(*this, &Init, 1), 5308 &DclT); 5309 if (Result.isInvalid()) { 5310 VDecl->setInvalidDecl(); 5311 return; 5312 } 5313 5314 Init = Result.takeAs<Expr>(); 5315 5316 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 5317 // Don't check invalid declarations to avoid emitting useless diagnostics. 5318 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5319 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 5320 CheckForConstantInitializer(Init, DclT); 5321 } 5322 } 5323 } else if (VDecl->isStaticDataMember() && 5324 VDecl->getLexicalDeclContext()->isRecord()) { 5325 // This is an in-class initialization for a static data member, e.g., 5326 // 5327 // struct S { 5328 // static const int value = 17; 5329 // }; 5330 5331 // Try to perform the initialization regardless. 5332 if (!VDecl->isInvalidDecl()) { 5333 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5334 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5335 MultiExprArg(*this, &Init, 1), 5336 &DclT); 5337 if (Result.isInvalid()) { 5338 VDecl->setInvalidDecl(); 5339 return; 5340 } 5341 5342 Init = Result.takeAs<Expr>(); 5343 } 5344 5345 // C++ [class.mem]p4: 5346 // A member-declarator can contain a constant-initializer only 5347 // if it declares a static member (9.4) of const integral or 5348 // const enumeration type, see 9.4.2. 5349 QualType T = VDecl->getType(); 5350 5351 // Do nothing on dependent types. 5352 if (T->isDependentType()) { 5353 5354 // Require constness. 5355 } else if (!T.isConstQualified()) { 5356 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 5357 << Init->getSourceRange(); 5358 VDecl->setInvalidDecl(); 5359 5360 // We allow integer constant expressions in all cases. 5361 } else if (T->isIntegralOrEnumerationType()) { 5362 if (!Init->isValueDependent()) { 5363 // Check whether the expression is a constant expression. 5364 llvm::APSInt Value; 5365 SourceLocation Loc; 5366 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 5367 Diag(Loc, diag::err_in_class_initializer_non_constant) 5368 << Init->getSourceRange(); 5369 VDecl->setInvalidDecl(); 5370 } 5371 } 5372 5373 // We allow floating-point constants as an extension in C++03, and 5374 // C++0x has far more complicated rules that we don't really 5375 // implement fully. 5376 } else { 5377 bool Allowed = false; 5378 if (getLangOptions().CPlusPlus0x) { 5379 Allowed = T->isLiteralType(); 5380 } else if (T->isFloatingType()) { // also permits complex, which is ok 5381 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 5382 << T << Init->getSourceRange(); 5383 Allowed = true; 5384 } 5385 5386 if (!Allowed) { 5387 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 5388 << T << Init->getSourceRange(); 5389 VDecl->setInvalidDecl(); 5390 5391 // TODO: there are probably expressions that pass here that shouldn't. 5392 } else if (!Init->isValueDependent() && 5393 !Init->isConstantInitializer(Context, false)) { 5394 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 5395 << Init->getSourceRange(); 5396 VDecl->setInvalidDecl(); 5397 } 5398 } 5399 } else if (VDecl->isFileVarDecl()) { 5400 if (VDecl->getStorageClassAsWritten() == SC_Extern && 5401 (!getLangOptions().CPlusPlus || 5402 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 5403 Diag(VDecl->getLocation(), diag::warn_extern_init); 5404 if (!VDecl->isInvalidDecl()) { 5405 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5406 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5407 MultiExprArg(*this, &Init, 1), 5408 &DclT); 5409 if (Result.isInvalid()) { 5410 VDecl->setInvalidDecl(); 5411 return; 5412 } 5413 5414 Init = Result.takeAs<Expr>(); 5415 } 5416 5417 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 5418 // Don't check invalid declarations to avoid emitting useless diagnostics. 5419 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5420 // C99 6.7.8p4. All file scoped initializers need to be constant. 5421 CheckForConstantInitializer(Init, DclT); 5422 } 5423 } 5424 // If the type changed, it means we had an incomplete type that was 5425 // completed by the initializer. For example: 5426 // int ary[] = { 1, 3, 5 }; 5427 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 5428 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 5429 VDecl->setType(DclT); 5430 Init->setType(DclT); 5431 } 5432 5433 5434 // If this variable is a local declaration with record type, make sure it 5435 // doesn't have a flexible member initialization. We only support this as a 5436 // global/static definition. 5437 if (VDecl->hasLocalStorage()) 5438 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 5439 if (RT->getDecl()->hasFlexibleArrayMember()) { 5440 // Check whether the initializer tries to initialize the flexible 5441 // array member itself to anything other than an empty initializer list. 5442 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 5443 unsigned Index = std::distance(RT->getDecl()->field_begin(), 5444 RT->getDecl()->field_end()) - 1; 5445 if (Index < ILE->getNumInits() && 5446 !(isa<InitListExpr>(ILE->getInit(Index)) && 5447 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 5448 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 5449 VDecl->setInvalidDecl(); 5450 } 5451 } 5452 } 5453 5454 // Check any implicit conversions within the expression. 5455 CheckImplicitConversions(Init, VDecl->getLocation()); 5456 5457 Init = MaybeCreateExprWithCleanups(Init); 5458 // Attach the initializer to the decl. 5459 VDecl->setInit(Init); 5460 5461 CheckCompleteVariableDeclaration(VDecl); 5462} 5463 5464/// ActOnInitializerError - Given that there was an error parsing an 5465/// initializer for the given declaration, try to return to some form 5466/// of sanity. 5467void Sema::ActOnInitializerError(Decl *D) { 5468 // Our main concern here is re-establishing invariants like "a 5469 // variable's type is either dependent or complete". 5470 if (!D || D->isInvalidDecl()) return; 5471 5472 VarDecl *VD = dyn_cast<VarDecl>(D); 5473 if (!VD) return; 5474 5475 // Auto types are meaningless if we can't make sense of the initializer. 5476 if (ParsingInitForAutoVars.count(D)) { 5477 D->setInvalidDecl(); 5478 return; 5479 } 5480 5481 QualType Ty = VD->getType(); 5482 if (Ty->isDependentType()) return; 5483 5484 // Require a complete type. 5485 if (RequireCompleteType(VD->getLocation(), 5486 Context.getBaseElementType(Ty), 5487 diag::err_typecheck_decl_incomplete_type)) { 5488 VD->setInvalidDecl(); 5489 return; 5490 } 5491 5492 // Require an abstract type. 5493 if (RequireNonAbstractType(VD->getLocation(), Ty, 5494 diag::err_abstract_type_in_decl, 5495 AbstractVariableType)) { 5496 VD->setInvalidDecl(); 5497 return; 5498 } 5499 5500 // Don't bother complaining about constructors or destructors, 5501 // though. 5502} 5503 5504void Sema::ActOnUninitializedDecl(Decl *RealDecl, 5505 bool TypeMayContainAuto) { 5506 // If there is no declaration, there was an error parsing it. Just ignore it. 5507 if (RealDecl == 0) 5508 return; 5509 5510 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 5511 QualType Type = Var->getType(); 5512 5513 // C++0x [dcl.spec.auto]p3 5514 if (TypeMayContainAuto && Type->getContainedAutoType()) { 5515 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 5516 << Var->getDeclName() << Type; 5517 Var->setInvalidDecl(); 5518 return; 5519 } 5520 5521 switch (Var->isThisDeclarationADefinition()) { 5522 case VarDecl::Definition: 5523 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 5524 break; 5525 5526 // We have an out-of-line definition of a static data member 5527 // that has an in-class initializer, so we type-check this like 5528 // a declaration. 5529 // 5530 // Fall through 5531 5532 case VarDecl::DeclarationOnly: 5533 // It's only a declaration. 5534 5535 // Block scope. C99 6.7p7: If an identifier for an object is 5536 // declared with no linkage (C99 6.2.2p6), the type for the 5537 // object shall be complete. 5538 if (!Type->isDependentType() && Var->isLocalVarDecl() && 5539 !Var->getLinkage() && !Var->isInvalidDecl() && 5540 RequireCompleteType(Var->getLocation(), Type, 5541 diag::err_typecheck_decl_incomplete_type)) 5542 Var->setInvalidDecl(); 5543 5544 // Make sure that the type is not abstract. 5545 if (!Type->isDependentType() && !Var->isInvalidDecl() && 5546 RequireNonAbstractType(Var->getLocation(), Type, 5547 diag::err_abstract_type_in_decl, 5548 AbstractVariableType)) 5549 Var->setInvalidDecl(); 5550 return; 5551 5552 case VarDecl::TentativeDefinition: 5553 // File scope. C99 6.9.2p2: A declaration of an identifier for an 5554 // object that has file scope without an initializer, and without a 5555 // storage-class specifier or with the storage-class specifier "static", 5556 // constitutes a tentative definition. Note: A tentative definition with 5557 // external linkage is valid (C99 6.2.2p5). 5558 if (!Var->isInvalidDecl()) { 5559 if (const IncompleteArrayType *ArrayT 5560 = Context.getAsIncompleteArrayType(Type)) { 5561 if (RequireCompleteType(Var->getLocation(), 5562 ArrayT->getElementType(), 5563 diag::err_illegal_decl_array_incomplete_type)) 5564 Var->setInvalidDecl(); 5565 } else if (Var->getStorageClass() == SC_Static) { 5566 // C99 6.9.2p3: If the declaration of an identifier for an object is 5567 // a tentative definition and has internal linkage (C99 6.2.2p3), the 5568 // declared type shall not be an incomplete type. 5569 // NOTE: code such as the following 5570 // static struct s; 5571 // struct s { int a; }; 5572 // is accepted by gcc. Hence here we issue a warning instead of 5573 // an error and we do not invalidate the static declaration. 5574 // NOTE: to avoid multiple warnings, only check the first declaration. 5575 if (Var->getPreviousDeclaration() == 0) 5576 RequireCompleteType(Var->getLocation(), Type, 5577 diag::ext_typecheck_decl_incomplete_type); 5578 } 5579 } 5580 5581 // Record the tentative definition; we're done. 5582 if (!Var->isInvalidDecl()) 5583 TentativeDefinitions.push_back(Var); 5584 return; 5585 } 5586 5587 // Provide a specific diagnostic for uninitialized variable 5588 // definitions with incomplete array type. 5589 if (Type->isIncompleteArrayType()) { 5590 Diag(Var->getLocation(), 5591 diag::err_typecheck_incomplete_array_needs_initializer); 5592 Var->setInvalidDecl(); 5593 return; 5594 } 5595 5596 // Provide a specific diagnostic for uninitialized variable 5597 // definitions with reference type. 5598 if (Type->isReferenceType()) { 5599 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5600 << Var->getDeclName() 5601 << SourceRange(Var->getLocation(), Var->getLocation()); 5602 Var->setInvalidDecl(); 5603 return; 5604 } 5605 5606 // Do not attempt to type-check the default initializer for a 5607 // variable with dependent type. 5608 if (Type->isDependentType()) 5609 return; 5610 5611 if (Var->isInvalidDecl()) 5612 return; 5613 5614 if (RequireCompleteType(Var->getLocation(), 5615 Context.getBaseElementType(Type), 5616 diag::err_typecheck_decl_incomplete_type)) { 5617 Var->setInvalidDecl(); 5618 return; 5619 } 5620 5621 // The variable can not have an abstract class type. 5622 if (RequireNonAbstractType(Var->getLocation(), Type, 5623 diag::err_abstract_type_in_decl, 5624 AbstractVariableType)) { 5625 Var->setInvalidDecl(); 5626 return; 5627 } 5628 5629 // Check for jumps past the implicit initializer. C++0x 5630 // clarifies that this applies to a "variable with automatic 5631 // storage duration", not a "local variable". 5632 // C++0x [stmt.dcl]p3 5633 // A program that jumps from a point where a variable with automatic 5634 // storage duration is not in scope to a point where it is in scope is 5635 // ill-formed unless the variable has scalar type, class type with a 5636 // trivial default constructor and a trivial destructor, a cv-qualified 5637 // version of one of these types, or an array of one of the preceding 5638 // types and is declared without an initializer. 5639 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) { 5640 if (const RecordType *Record 5641 = Context.getBaseElementType(Type)->getAs<RecordType>()) { 5642 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl()); 5643 if ((!getLangOptions().CPlusPlus0x && !CXXRecord->isPOD()) || 5644 (getLangOptions().CPlusPlus0x && 5645 (!CXXRecord->hasTrivialDefaultConstructor() || 5646 (!CXXRecord->hasTrivialDestructor())))) 5647 getCurFunction()->setHasBranchProtectedScope(); 5648 } 5649 } 5650 5651 // C++03 [dcl.init]p9: 5652 // If no initializer is specified for an object, and the 5653 // object is of (possibly cv-qualified) non-POD class type (or 5654 // array thereof), the object shall be default-initialized; if 5655 // the object is of const-qualified type, the underlying class 5656 // type shall have a user-declared default 5657 // constructor. Otherwise, if no initializer is specified for 5658 // a non- static object, the object and its subobjects, if 5659 // any, have an indeterminate initial value); if the object 5660 // or any of its subobjects are of const-qualified type, the 5661 // program is ill-formed. 5662 // C++0x [dcl.init]p11: 5663 // If no initializer is specified for an object, the object is 5664 // default-initialized; [...]. 5665 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5666 InitializationKind Kind 5667 = InitializationKind::CreateDefault(Var->getLocation()); 5668 5669 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5670 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5671 MultiExprArg(*this, 0, 0)); 5672 if (Init.isInvalid()) 5673 Var->setInvalidDecl(); 5674 else if (Init.get()) 5675 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5676 5677 CheckCompleteVariableDeclaration(Var); 5678 } 5679} 5680 5681void Sema::ActOnCXXForRangeDecl(Decl *D) { 5682 VarDecl *VD = dyn_cast<VarDecl>(D); 5683 if (!VD) { 5684 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var); 5685 D->setInvalidDecl(); 5686 return; 5687 } 5688 5689 VD->setCXXForRangeDecl(true); 5690 5691 // for-range-declaration cannot be given a storage class specifier. 5692 int Error = -1; 5693 switch (VD->getStorageClassAsWritten()) { 5694 case SC_None: 5695 break; 5696 case SC_Extern: 5697 Error = 0; 5698 break; 5699 case SC_Static: 5700 Error = 1; 5701 break; 5702 case SC_PrivateExtern: 5703 Error = 2; 5704 break; 5705 case SC_Auto: 5706 Error = 3; 5707 break; 5708 case SC_Register: 5709 Error = 4; 5710 break; 5711 } 5712 // FIXME: constexpr isn't allowed here. 5713 //if (DS.isConstexprSpecified()) 5714 // Error = 5; 5715 if (Error != -1) { 5716 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class) 5717 << VD->getDeclName() << Error; 5718 D->setInvalidDecl(); 5719 } 5720} 5721 5722void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5723 if (var->isInvalidDecl()) return; 5724 5725 // All the following checks are C++ only. 5726 if (!getLangOptions().CPlusPlus) return; 5727 5728 QualType baseType = Context.getBaseElementType(var->getType()); 5729 if (baseType->isDependentType()) return; 5730 5731 // __block variables might require us to capture a copy-initializer. 5732 if (var->hasAttr<BlocksAttr>()) { 5733 // It's currently invalid to ever have a __block variable with an 5734 // array type; should we diagnose that here? 5735 5736 // Regardless, we don't want to ignore array nesting when 5737 // constructing this copy. 5738 QualType type = var->getType(); 5739 5740 if (type->isStructureOrClassType()) { 5741 SourceLocation poi = var->getLocation(); 5742 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5743 ExprResult result = 5744 PerformCopyInitialization( 5745 InitializedEntity::InitializeBlock(poi, type, false), 5746 poi, Owned(varRef)); 5747 if (!result.isInvalid()) { 5748 result = MaybeCreateExprWithCleanups(result); 5749 Expr *init = result.takeAs<Expr>(); 5750 Context.setBlockVarCopyInits(var, init); 5751 } 5752 } 5753 } 5754 5755 // Check for global constructors. 5756 if (!var->getDeclContext()->isDependentContext() && 5757 var->hasGlobalStorage() && 5758 !var->isStaticLocal() && 5759 var->getInit() && 5760 !var->getInit()->isConstantInitializer(Context, 5761 baseType->isReferenceType())) 5762 Diag(var->getLocation(), diag::warn_global_constructor) 5763 << var->getInit()->getSourceRange(); 5764 5765 // Require the destructor. 5766 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5767 FinalizeVarWithDestructor(var, recordType); 5768} 5769 5770/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5771/// any semantic actions necessary after any initializer has been attached. 5772void 5773Sema::FinalizeDeclaration(Decl *ThisDecl) { 5774 // Note that we are no longer parsing the initializer for this declaration. 5775 ParsingInitForAutoVars.erase(ThisDecl); 5776} 5777 5778Sema::DeclGroupPtrTy 5779Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5780 Decl **Group, unsigned NumDecls) { 5781 llvm::SmallVector<Decl*, 8> Decls; 5782 5783 if (DS.isTypeSpecOwned()) 5784 Decls.push_back(DS.getRepAsDecl()); 5785 5786 for (unsigned i = 0; i != NumDecls; ++i) 5787 if (Decl *D = Group[i]) 5788 Decls.push_back(D); 5789 5790 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5791 DS.getTypeSpecType() == DeclSpec::TST_auto); 5792} 5793 5794/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5795/// group, performing any necessary semantic checking. 5796Sema::DeclGroupPtrTy 5797Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5798 bool TypeMayContainAuto) { 5799 // C++0x [dcl.spec.auto]p7: 5800 // If the type deduced for the template parameter U is not the same in each 5801 // deduction, the program is ill-formed. 5802 // FIXME: When initializer-list support is added, a distinction is needed 5803 // between the deduced type U and the deduced type which 'auto' stands for. 5804 // auto a = 0, b = { 1, 2, 3 }; 5805 // is legal because the deduced type U is 'int' in both cases. 5806 if (TypeMayContainAuto && NumDecls > 1) { 5807 QualType Deduced; 5808 CanQualType DeducedCanon; 5809 VarDecl *DeducedDecl = 0; 5810 for (unsigned i = 0; i != NumDecls; ++i) { 5811 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5812 AutoType *AT = D->getType()->getContainedAutoType(); 5813 // Don't reissue diagnostics when instantiating a template. 5814 if (AT && D->isInvalidDecl()) 5815 break; 5816 if (AT && AT->isDeduced()) { 5817 QualType U = AT->getDeducedType(); 5818 CanQualType UCanon = Context.getCanonicalType(U); 5819 if (Deduced.isNull()) { 5820 Deduced = U; 5821 DeducedCanon = UCanon; 5822 DeducedDecl = D; 5823 } else if (DeducedCanon != UCanon) { 5824 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5825 diag::err_auto_different_deductions) 5826 << Deduced << DeducedDecl->getDeclName() 5827 << U << D->getDeclName() 5828 << DeducedDecl->getInit()->getSourceRange() 5829 << D->getInit()->getSourceRange(); 5830 D->setInvalidDecl(); 5831 break; 5832 } 5833 } 5834 } 5835 } 5836 } 5837 5838 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5839} 5840 5841 5842/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5843/// to introduce parameters into function prototype scope. 5844Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5845 const DeclSpec &DS = D.getDeclSpec(); 5846 5847 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5848 VarDecl::StorageClass StorageClass = SC_None; 5849 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5850 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5851 StorageClass = SC_Register; 5852 StorageClassAsWritten = SC_Register; 5853 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5854 Diag(DS.getStorageClassSpecLoc(), 5855 diag::err_invalid_storage_class_in_func_decl); 5856 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5857 } 5858 5859 if (D.getDeclSpec().isThreadSpecified()) 5860 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5861 5862 DiagnoseFunctionSpecifiers(D); 5863 5864 TagDecl *OwnedDecl = 0; 5865 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 5866 QualType parmDeclType = TInfo->getType(); 5867 5868 if (getLangOptions().CPlusPlus) { 5869 // Check that there are no default arguments inside the type of this 5870 // parameter. 5871 CheckExtraCXXDefaultArguments(D); 5872 5873 if (OwnedDecl && OwnedDecl->isDefinition()) { 5874 // C++ [dcl.fct]p6: 5875 // Types shall not be defined in return or parameter types. 5876 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 5877 << Context.getTypeDeclType(OwnedDecl); 5878 } 5879 5880 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5881 if (D.getCXXScopeSpec().isSet()) { 5882 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5883 << D.getCXXScopeSpec().getRange(); 5884 D.getCXXScopeSpec().clear(); 5885 } 5886 } 5887 5888 // Ensure we have a valid name 5889 IdentifierInfo *II = 0; 5890 if (D.hasName()) { 5891 II = D.getIdentifier(); 5892 if (!II) { 5893 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5894 << GetNameForDeclarator(D).getName().getAsString(); 5895 D.setInvalidType(true); 5896 } 5897 } 5898 5899 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 5900 if (II) { 5901 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 5902 ForRedeclaration); 5903 LookupName(R, S); 5904 if (R.isSingleResult()) { 5905 NamedDecl *PrevDecl = R.getFoundDecl(); 5906 if (PrevDecl->isTemplateParameter()) { 5907 // Maybe we will complain about the shadowed template parameter. 5908 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5909 // Just pretend that we didn't see the previous declaration. 5910 PrevDecl = 0; 5911 } else if (S->isDeclScope(PrevDecl)) { 5912 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 5913 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5914 5915 // Recover by removing the name 5916 II = 0; 5917 D.SetIdentifier(0, D.getIdentifierLoc()); 5918 D.setInvalidType(true); 5919 } 5920 } 5921 } 5922 5923 // Temporarily put parameter variables in the translation unit, not 5924 // the enclosing context. This prevents them from accidentally 5925 // looking like class members in C++. 5926 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 5927 D.getSourceRange().getBegin(), 5928 D.getIdentifierLoc(), II, 5929 parmDeclType, TInfo, 5930 StorageClass, StorageClassAsWritten); 5931 5932 if (D.isInvalidType()) 5933 New->setInvalidDecl(); 5934 5935 assert(S->isFunctionPrototypeScope()); 5936 assert(S->getFunctionPrototypeDepth() >= 1); 5937 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1, 5938 S->getNextFunctionPrototypeIndex()); 5939 5940 // Add the parameter declaration into this scope. 5941 S->AddDecl(New); 5942 if (II) 5943 IdResolver.AddDecl(New); 5944 5945 ProcessDeclAttributes(S, New, D); 5946 5947 if (New->hasAttr<BlocksAttr>()) { 5948 Diag(New->getLocation(), diag::err_block_on_nonlocal); 5949 } 5950 return New; 5951} 5952 5953/// \brief Synthesizes a variable for a parameter arising from a 5954/// typedef. 5955ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 5956 SourceLocation Loc, 5957 QualType T) { 5958 /* FIXME: setting StartLoc == Loc. 5959 Would it be worth to modify callers so as to provide proper source 5960 location for the unnamed parameters, embedding the parameter's type? */ 5961 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, 5962 T, Context.getTrivialTypeSourceInfo(T, Loc), 5963 SC_None, SC_None, 0); 5964 Param->setImplicit(); 5965 return Param; 5966} 5967 5968void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 5969 ParmVarDecl * const *ParamEnd) { 5970 // Don't diagnose unused-parameter errors in template instantiations; we 5971 // will already have done so in the template itself. 5972 if (!ActiveTemplateInstantiations.empty()) 5973 return; 5974 5975 for (; Param != ParamEnd; ++Param) { 5976 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 5977 !(*Param)->hasAttr<UnusedAttr>()) { 5978 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 5979 << (*Param)->getDeclName(); 5980 } 5981 } 5982} 5983 5984void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 5985 ParmVarDecl * const *ParamEnd, 5986 QualType ReturnTy, 5987 NamedDecl *D) { 5988 if (LangOpts.NumLargeByValueCopy == 0) // No check. 5989 return; 5990 5991 // Warn if the return value is pass-by-value and larger than the specified 5992 // threshold. 5993 if (ReturnTy->isPODType()) { 5994 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 5995 if (Size > LangOpts.NumLargeByValueCopy) 5996 Diag(D->getLocation(), diag::warn_return_value_size) 5997 << D->getDeclName() << Size; 5998 } 5999 6000 // Warn if any parameter is pass-by-value and larger than the specified 6001 // threshold. 6002 for (; Param != ParamEnd; ++Param) { 6003 QualType T = (*Param)->getType(); 6004 if (!T->isPODType()) 6005 continue; 6006 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 6007 if (Size > LangOpts.NumLargeByValueCopy) 6008 Diag((*Param)->getLocation(), diag::warn_parameter_size) 6009 << (*Param)->getDeclName() << Size; 6010 } 6011} 6012 6013ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, 6014 SourceLocation NameLoc, IdentifierInfo *Name, 6015 QualType T, TypeSourceInfo *TSInfo, 6016 VarDecl::StorageClass StorageClass, 6017 VarDecl::StorageClass StorageClassAsWritten) { 6018 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, 6019 adjustParameterType(T), TSInfo, 6020 StorageClass, StorageClassAsWritten, 6021 0); 6022 6023 // Parameters can not be abstract class types. 6024 // For record types, this is done by the AbstractClassUsageDiagnoser once 6025 // the class has been completely parsed. 6026 if (!CurContext->isRecord() && 6027 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 6028 AbstractParamType)) 6029 New->setInvalidDecl(); 6030 6031 // Parameter declarators cannot be interface types. All ObjC objects are 6032 // passed by reference. 6033 if (T->isObjCObjectType()) { 6034 Diag(NameLoc, 6035 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 6036 New->setInvalidDecl(); 6037 } 6038 6039 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 6040 // duration shall not be qualified by an address-space qualifier." 6041 // Since all parameters have automatic store duration, they can not have 6042 // an address space. 6043 if (T.getAddressSpace() != 0) { 6044 Diag(NameLoc, diag::err_arg_with_address_space); 6045 New->setInvalidDecl(); 6046 } 6047 6048 return New; 6049} 6050 6051void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 6052 SourceLocation LocAfterDecls) { 6053 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 6054 6055 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 6056 // for a K&R function. 6057 if (!FTI.hasPrototype) { 6058 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 6059 --i; 6060 if (FTI.ArgInfo[i].Param == 0) { 6061 llvm::SmallString<256> Code; 6062 llvm::raw_svector_ostream(Code) << " int " 6063 << FTI.ArgInfo[i].Ident->getName() 6064 << ";\n"; 6065 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 6066 << FTI.ArgInfo[i].Ident 6067 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 6068 6069 // Implicitly declare the argument as type 'int' for lack of a better 6070 // type. 6071 AttributeFactory attrs; 6072 DeclSpec DS(attrs); 6073 const char* PrevSpec; // unused 6074 unsigned DiagID; // unused 6075 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 6076 PrevSpec, DiagID); 6077 Declarator ParamD(DS, Declarator::KNRTypeListContext); 6078 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 6079 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 6080 } 6081 } 6082 } 6083} 6084 6085Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 6086 Declarator &D) { 6087 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 6088 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 6089 Scope *ParentScope = FnBodyScope->getParent(); 6090 6091 Decl *DP = HandleDeclarator(ParentScope, D, 6092 MultiTemplateParamsArg(*this), 6093 /*IsFunctionDefinition=*/true); 6094 return ActOnStartOfFunctionDef(FnBodyScope, DP); 6095} 6096 6097static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 6098 // Don't warn about invalid declarations. 6099 if (FD->isInvalidDecl()) 6100 return false; 6101 6102 // Or declarations that aren't global. 6103 if (!FD->isGlobal()) 6104 return false; 6105 6106 // Don't warn about C++ member functions. 6107 if (isa<CXXMethodDecl>(FD)) 6108 return false; 6109 6110 // Don't warn about 'main'. 6111 if (FD->isMain()) 6112 return false; 6113 6114 // Don't warn about inline functions. 6115 if (FD->isInlined()) 6116 return false; 6117 6118 // Don't warn about function templates. 6119 if (FD->getDescribedFunctionTemplate()) 6120 return false; 6121 6122 // Don't warn about function template specializations. 6123 if (FD->isFunctionTemplateSpecialization()) 6124 return false; 6125 6126 bool MissingPrototype = true; 6127 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 6128 Prev; Prev = Prev->getPreviousDeclaration()) { 6129 // Ignore any declarations that occur in function or method 6130 // scope, because they aren't visible from the header. 6131 if (Prev->getDeclContext()->isFunctionOrMethod()) 6132 continue; 6133 6134 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 6135 break; 6136 } 6137 6138 return MissingPrototype; 6139} 6140 6141void Sema::CheckForFunctionRedefinition(FunctionDecl *FD) { 6142 // Don't complain if we're in GNU89 mode and the previous definition 6143 // was an extern inline function. 6144 const FunctionDecl *Definition; 6145 if (FD->isDefined(Definition) && 6146 !canRedefineFunction(Definition, getLangOptions())) { 6147 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 6148 Definition->getStorageClass() == SC_Extern) 6149 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 6150 << FD->getDeclName() << getLangOptions().CPlusPlus; 6151 else 6152 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 6153 Diag(Definition->getLocation(), diag::note_previous_definition); 6154 } 6155} 6156 6157Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 6158 // Clear the last template instantiation error context. 6159 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 6160 6161 if (!D) 6162 return D; 6163 FunctionDecl *FD = 0; 6164 6165 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 6166 FD = FunTmpl->getTemplatedDecl(); 6167 else 6168 FD = cast<FunctionDecl>(D); 6169 6170 // Enter a new function scope 6171 PushFunctionScope(); 6172 6173 // See if this is a redefinition. 6174 if (!FD->isLateTemplateParsed()) 6175 CheckForFunctionRedefinition(FD); 6176 6177 // Builtin functions cannot be defined. 6178 if (unsigned BuiltinID = FD->getBuiltinID()) { 6179 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 6180 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 6181 FD->setInvalidDecl(); 6182 } 6183 } 6184 6185 // The return type of a function definition must be complete 6186 // (C99 6.9.1p3, C++ [dcl.fct]p6). 6187 QualType ResultType = FD->getResultType(); 6188 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 6189 !FD->isInvalidDecl() && 6190 RequireCompleteType(FD->getLocation(), ResultType, 6191 diag::err_func_def_incomplete_result)) 6192 FD->setInvalidDecl(); 6193 6194 // GNU warning -Wmissing-prototypes: 6195 // Warn if a global function is defined without a previous 6196 // prototype declaration. This warning is issued even if the 6197 // definition itself provides a prototype. The aim is to detect 6198 // global functions that fail to be declared in header files. 6199 if (ShouldWarnAboutMissingPrototype(FD)) 6200 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 6201 6202 if (FnBodyScope) 6203 PushDeclContext(FnBodyScope, FD); 6204 6205 // Check the validity of our function parameters 6206 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 6207 /*CheckParameterNames=*/true); 6208 6209 // Introduce our parameters into the function scope 6210 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 6211 ParmVarDecl *Param = FD->getParamDecl(p); 6212 Param->setOwningFunction(FD); 6213 6214 // If this has an identifier, add it to the scope stack. 6215 if (Param->getIdentifier() && FnBodyScope) { 6216 CheckShadow(FnBodyScope, Param); 6217 6218 PushOnScopeChains(Param, FnBodyScope); 6219 } 6220 } 6221 6222 // Checking attributes of current function definition 6223 // dllimport attribute. 6224 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 6225 if (DA && (!FD->getAttr<DLLExportAttr>())) { 6226 // dllimport attribute cannot be directly applied to definition. 6227 // Microsoft accepts dllimport for functions defined within class scope. 6228 if (!DA->isInherited() && 6229 !(LangOpts.Microsoft && FD->getLexicalDeclContext()->isRecord())) { 6230 Diag(FD->getLocation(), 6231 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 6232 << "dllimport"; 6233 FD->setInvalidDecl(); 6234 return FD; 6235 } 6236 6237 // Visual C++ appears to not think this is an issue, so only issue 6238 // a warning when Microsoft extensions are disabled. 6239 if (!LangOpts.Microsoft) { 6240 // If a symbol previously declared dllimport is later defined, the 6241 // attribute is ignored in subsequent references, and a warning is 6242 // emitted. 6243 Diag(FD->getLocation(), 6244 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 6245 << FD->getName() << "dllimport"; 6246 } 6247 } 6248 return FD; 6249} 6250 6251/// \brief Given the set of return statements within a function body, 6252/// compute the variables that are subject to the named return value 6253/// optimization. 6254/// 6255/// Each of the variables that is subject to the named return value 6256/// optimization will be marked as NRVO variables in the AST, and any 6257/// return statement that has a marked NRVO variable as its NRVO candidate can 6258/// use the named return value optimization. 6259/// 6260/// This function applies a very simplistic algorithm for NRVO: if every return 6261/// statement in the function has the same NRVO candidate, that candidate is 6262/// the NRVO variable. 6263/// 6264/// FIXME: Employ a smarter algorithm that accounts for multiple return 6265/// statements and the lifetimes of the NRVO candidates. We should be able to 6266/// find a maximal set of NRVO variables. 6267static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 6268 ReturnStmt **Returns = Scope->Returns.data(); 6269 6270 const VarDecl *NRVOCandidate = 0; 6271 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 6272 if (!Returns[I]->getNRVOCandidate()) 6273 return; 6274 6275 if (!NRVOCandidate) 6276 NRVOCandidate = Returns[I]->getNRVOCandidate(); 6277 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 6278 return; 6279 } 6280 6281 if (NRVOCandidate) 6282 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 6283} 6284 6285Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 6286 return ActOnFinishFunctionBody(D, move(BodyArg), false); 6287} 6288 6289Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 6290 bool IsInstantiation) { 6291 FunctionDecl *FD = 0; 6292 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 6293 if (FunTmpl) 6294 FD = FunTmpl->getTemplatedDecl(); 6295 else 6296 FD = dyn_cast_or_null<FunctionDecl>(dcl); 6297 6298 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 6299 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 6300 6301 if (FD) { 6302 FD->setBody(Body); 6303 if (FD->isMain()) { 6304 // C and C++ allow for main to automagically return 0. 6305 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 6306 FD->setHasImplicitReturnZero(true); 6307 WP.disableCheckFallThrough(); 6308 } 6309 6310 // MSVC permits the use of pure specifier (=0) on function definition, 6311 // defined at class scope, warn about this non standard construct. 6312 if (getLangOptions().Microsoft && FD->isPure()) 6313 Diag(FD->getLocation(), diag::warn_pure_function_definition); 6314 6315 if (!FD->isInvalidDecl()) { 6316 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 6317 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 6318 FD->getResultType(), FD); 6319 6320 // If this is a constructor, we need a vtable. 6321 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 6322 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 6323 6324 ComputeNRVO(Body, getCurFunction()); 6325 } 6326 6327 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 6328 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 6329 assert(MD == getCurMethodDecl() && "Method parsing confused"); 6330 MD->setBody(Body); 6331 if (Body) 6332 MD->setEndLoc(Body->getLocEnd()); 6333 if (!MD->isInvalidDecl()) { 6334 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 6335 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 6336 MD->getResultType(), MD); 6337 } 6338 } else { 6339 return 0; 6340 } 6341 6342 // Verify and clean out per-function state. 6343 if (Body) { 6344 // C++ constructors that have function-try-blocks can't have return 6345 // statements in the handlers of that block. (C++ [except.handle]p14) 6346 // Verify this. 6347 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 6348 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 6349 6350 // Verify that that gotos and switch cases don't jump into scopes illegally. 6351 // Verify that that gotos and switch cases don't jump into scopes illegally. 6352 if (getCurFunction()->NeedsScopeChecking() && 6353 !dcl->isInvalidDecl() && 6354 !hasAnyErrorsInThisFunction()) 6355 DiagnoseInvalidJumps(Body); 6356 6357 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 6358 if (!Destructor->getParent()->isDependentType()) 6359 CheckDestructor(Destructor); 6360 6361 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 6362 Destructor->getParent()); 6363 } 6364 6365 // If any errors have occurred, clear out any temporaries that may have 6366 // been leftover. This ensures that these temporaries won't be picked up for 6367 // deletion in some later function. 6368 if (PP.getDiagnostics().hasErrorOccurred() || 6369 PP.getDiagnostics().getSuppressAllDiagnostics()) 6370 ExprTemporaries.clear(); 6371 else if (!isa<FunctionTemplateDecl>(dcl)) { 6372 // Since the body is valid, issue any analysis-based warnings that are 6373 // enabled. 6374 ActivePolicy = &WP; 6375 } 6376 6377 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 6378 } 6379 6380 if (!IsInstantiation) 6381 PopDeclContext(); 6382 6383 PopFunctionOrBlockScope(ActivePolicy, dcl); 6384 6385 // If any errors have occurred, clear out any temporaries that may have 6386 // been leftover. This ensures that these temporaries won't be picked up for 6387 // deletion in some later function. 6388 if (getDiagnostics().hasErrorOccurred()) 6389 ExprTemporaries.clear(); 6390 6391 return dcl; 6392} 6393 6394/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 6395/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 6396NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 6397 IdentifierInfo &II, Scope *S) { 6398 // Before we produce a declaration for an implicitly defined 6399 // function, see whether there was a locally-scoped declaration of 6400 // this name as a function or variable. If so, use that 6401 // (non-visible) declaration, and complain about it. 6402 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 6403 = LocallyScopedExternalDecls.find(&II); 6404 if (Pos != LocallyScopedExternalDecls.end()) { 6405 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 6406 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 6407 return Pos->second; 6408 } 6409 6410 // Extension in C99. Legal in C90, but warn about it. 6411 if (II.getName().startswith("__builtin_")) 6412 Diag(Loc, diag::warn_builtin_unknown) << &II; 6413 else if (getLangOptions().C99) 6414 Diag(Loc, diag::ext_implicit_function_decl) << &II; 6415 else 6416 Diag(Loc, diag::warn_implicit_function_decl) << &II; 6417 6418 // Set a Declarator for the implicit definition: int foo(); 6419 const char *Dummy; 6420 AttributeFactory attrFactory; 6421 DeclSpec DS(attrFactory); 6422 unsigned DiagID; 6423 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 6424 (void)Error; // Silence warning. 6425 assert(!Error && "Error setting up implicit decl!"); 6426 Declarator D(DS, Declarator::BlockContext); 6427 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 6428 0, 0, true, SourceLocation(), 6429 EST_None, SourceLocation(), 6430 0, 0, 0, 0, Loc, Loc, D), 6431 DS.getAttributes(), 6432 SourceLocation()); 6433 D.SetIdentifier(&II, Loc); 6434 6435 // Insert this function into translation-unit scope. 6436 6437 DeclContext *PrevDC = CurContext; 6438 CurContext = Context.getTranslationUnitDecl(); 6439 6440 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 6441 FD->setImplicit(); 6442 6443 CurContext = PrevDC; 6444 6445 AddKnownFunctionAttributes(FD); 6446 6447 return FD; 6448} 6449 6450/// \brief Adds any function attributes that we know a priori based on 6451/// the declaration of this function. 6452/// 6453/// These attributes can apply both to implicitly-declared builtins 6454/// (like __builtin___printf_chk) or to library-declared functions 6455/// like NSLog or printf. 6456void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 6457 if (FD->isInvalidDecl()) 6458 return; 6459 6460 // If this is a built-in function, map its builtin attributes to 6461 // actual attributes. 6462 if (unsigned BuiltinID = FD->getBuiltinID()) { 6463 // Handle printf-formatting attributes. 6464 unsigned FormatIdx; 6465 bool HasVAListArg; 6466 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 6467 if (!FD->getAttr<FormatAttr>()) 6468 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6469 "printf", FormatIdx+1, 6470 HasVAListArg ? 0 : FormatIdx+2)); 6471 } 6472 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 6473 HasVAListArg)) { 6474 if (!FD->getAttr<FormatAttr>()) 6475 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6476 "scanf", FormatIdx+1, 6477 HasVAListArg ? 0 : FormatIdx+2)); 6478 } 6479 6480 // Mark const if we don't care about errno and that is the only 6481 // thing preventing the function from being const. This allows 6482 // IRgen to use LLVM intrinsics for such functions. 6483 if (!getLangOptions().MathErrno && 6484 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 6485 if (!FD->getAttr<ConstAttr>()) 6486 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6487 } 6488 6489 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 6490 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 6491 if (Context.BuiltinInfo.isConst(BuiltinID)) 6492 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6493 } 6494 6495 IdentifierInfo *Name = FD->getIdentifier(); 6496 if (!Name) 6497 return; 6498 if ((!getLangOptions().CPlusPlus && 6499 FD->getDeclContext()->isTranslationUnit()) || 6500 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 6501 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 6502 LinkageSpecDecl::lang_c)) { 6503 // Okay: this could be a libc/libm/Objective-C function we know 6504 // about. 6505 } else 6506 return; 6507 6508 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 6509 // FIXME: NSLog and NSLogv should be target specific 6510 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 6511 // FIXME: We known better than our headers. 6512 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 6513 } else 6514 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6515 "printf", 1, 6516 Name->isStr("NSLogv") ? 0 : 2)); 6517 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 6518 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 6519 // target-specific builtins, perhaps? 6520 if (!FD->getAttr<FormatAttr>()) 6521 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6522 "printf", 2, 6523 Name->isStr("vasprintf") ? 0 : 3)); 6524 } 6525} 6526 6527TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 6528 TypeSourceInfo *TInfo) { 6529 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 6530 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 6531 6532 if (!TInfo) { 6533 assert(D.isInvalidType() && "no declarator info for valid type"); 6534 TInfo = Context.getTrivialTypeSourceInfo(T); 6535 } 6536 6537 // Scope manipulation handled by caller. 6538 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 6539 D.getSourceRange().getBegin(), 6540 D.getIdentifierLoc(), 6541 D.getIdentifier(), 6542 TInfo); 6543 6544 // Bail out immediately if we have an invalid declaration. 6545 if (D.isInvalidType()) { 6546 NewTD->setInvalidDecl(); 6547 return NewTD; 6548 } 6549 6550 // C++ [dcl.typedef]p8: 6551 // If the typedef declaration defines an unnamed class (or 6552 // enum), the first typedef-name declared by the declaration 6553 // to be that class type (or enum type) is used to denote the 6554 // class type (or enum type) for linkage purposes only. 6555 // We need to check whether the type was declared in the declaration. 6556 switch (D.getDeclSpec().getTypeSpecType()) { 6557 case TST_enum: 6558 case TST_struct: 6559 case TST_union: 6560 case TST_class: { 6561 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 6562 6563 // Do nothing if the tag is not anonymous or already has an 6564 // associated typedef (from an earlier typedef in this decl group). 6565 if (tagFromDeclSpec->getIdentifier()) break; 6566 if (tagFromDeclSpec->getTypedefNameForAnonDecl()) break; 6567 6568 // A well-formed anonymous tag must always be a TUK_Definition. 6569 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 6570 6571 // The type must match the tag exactly; no qualifiers allowed. 6572 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 6573 break; 6574 6575 // Otherwise, set this is the anon-decl typedef for the tag. 6576 tagFromDeclSpec->setTypedefNameForAnonDecl(NewTD); 6577 break; 6578 } 6579 6580 default: 6581 break; 6582 } 6583 6584 return NewTD; 6585} 6586 6587 6588/// \brief Determine whether a tag with a given kind is acceptable 6589/// as a redeclaration of the given tag declaration. 6590/// 6591/// \returns true if the new tag kind is acceptable, false otherwise. 6592bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 6593 TagTypeKind NewTag, 6594 SourceLocation NewTagLoc, 6595 const IdentifierInfo &Name) { 6596 // C++ [dcl.type.elab]p3: 6597 // The class-key or enum keyword present in the 6598 // elaborated-type-specifier shall agree in kind with the 6599 // declaration to which the name in the elaborated-type-specifier 6600 // refers. This rule also applies to the form of 6601 // elaborated-type-specifier that declares a class-name or 6602 // friend class since it can be construed as referring to the 6603 // definition of the class. Thus, in any 6604 // elaborated-type-specifier, the enum keyword shall be used to 6605 // refer to an enumeration (7.2), the union class-key shall be 6606 // used to refer to a union (clause 9), and either the class or 6607 // struct class-key shall be used to refer to a class (clause 9) 6608 // declared using the class or struct class-key. 6609 TagTypeKind OldTag = Previous->getTagKind(); 6610 if (OldTag == NewTag) 6611 return true; 6612 6613 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 6614 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 6615 // Warn about the struct/class tag mismatch. 6616 bool isTemplate = false; 6617 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 6618 isTemplate = Record->getDescribedClassTemplate(); 6619 6620 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6621 << (NewTag == TTK_Class) 6622 << isTemplate << &Name 6623 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 6624 OldTag == TTK_Class? "class" : "struct"); 6625 Diag(Previous->getLocation(), diag::note_previous_use); 6626 return true; 6627 } 6628 return false; 6629} 6630 6631/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 6632/// former case, Name will be non-null. In the later case, Name will be null. 6633/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 6634/// reference/declaration/definition of a tag. 6635Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 6636 SourceLocation KWLoc, CXXScopeSpec &SS, 6637 IdentifierInfo *Name, SourceLocation NameLoc, 6638 AttributeList *Attr, AccessSpecifier AS, 6639 MultiTemplateParamsArg TemplateParameterLists, 6640 bool &OwnedDecl, bool &IsDependent, 6641 bool ScopedEnum, bool ScopedEnumUsesClassTag, 6642 TypeResult UnderlyingType) { 6643 // If this is not a definition, it must have a name. 6644 assert((Name != 0 || TUK == TUK_Definition) && 6645 "Nameless record must be a definition!"); 6646 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 6647 6648 OwnedDecl = false; 6649 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 6650 6651 // FIXME: Check explicit specializations more carefully. 6652 bool isExplicitSpecialization = false; 6653 bool Invalid = false; 6654 6655 // We only need to do this matching if we have template parameters 6656 // or a scope specifier, which also conveniently avoids this work 6657 // for non-C++ cases. 6658 if (TemplateParameterLists.size() > 0 || 6659 (SS.isNotEmpty() && TUK != TUK_Reference)) { 6660 if (TemplateParameterList *TemplateParams 6661 = MatchTemplateParametersToScopeSpecifier(KWLoc, NameLoc, SS, 6662 TemplateParameterLists.get(), 6663 TemplateParameterLists.size(), 6664 TUK == TUK_Friend, 6665 isExplicitSpecialization, 6666 Invalid)) { 6667 if (TemplateParams->size() > 0) { 6668 // This is a declaration or definition of a class template (which may 6669 // be a member of another template). 6670 6671 if (Invalid) 6672 return 0; 6673 6674 OwnedDecl = false; 6675 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6676 SS, Name, NameLoc, Attr, 6677 TemplateParams, AS, 6678 TemplateParameterLists.size() - 1, 6679 (TemplateParameterList**) TemplateParameterLists.release()); 6680 return Result.get(); 6681 } else { 6682 // The "template<>" header is extraneous. 6683 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6684 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6685 isExplicitSpecialization = true; 6686 } 6687 } 6688 } 6689 6690 // Figure out the underlying type if this a enum declaration. We need to do 6691 // this early, because it's needed to detect if this is an incompatible 6692 // redeclaration. 6693 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6694 6695 if (Kind == TTK_Enum) { 6696 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6697 // No underlying type explicitly specified, or we failed to parse the 6698 // type, default to int. 6699 EnumUnderlying = Context.IntTy.getTypePtr(); 6700 else if (UnderlyingType.get()) { 6701 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6702 // integral type; any cv-qualification is ignored. 6703 TypeSourceInfo *TI = 0; 6704 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6705 EnumUnderlying = TI; 6706 6707 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6708 6709 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6710 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6711 << T; 6712 // Recover by falling back to int. 6713 EnumUnderlying = Context.IntTy.getTypePtr(); 6714 } 6715 6716 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6717 UPPC_FixedUnderlyingType)) 6718 EnumUnderlying = Context.IntTy.getTypePtr(); 6719 6720 } else if (getLangOptions().Microsoft) 6721 // Microsoft enums are always of int type. 6722 EnumUnderlying = Context.IntTy.getTypePtr(); 6723 } 6724 6725 DeclContext *SearchDC = CurContext; 6726 DeclContext *DC = CurContext; 6727 bool isStdBadAlloc = false; 6728 6729 RedeclarationKind Redecl = ForRedeclaration; 6730 if (TUK == TUK_Friend || TUK == TUK_Reference) 6731 Redecl = NotForRedeclaration; 6732 6733 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6734 6735 if (Name && SS.isNotEmpty()) { 6736 // We have a nested-name tag ('struct foo::bar'). 6737 6738 // Check for invalid 'foo::'. 6739 if (SS.isInvalid()) { 6740 Name = 0; 6741 goto CreateNewDecl; 6742 } 6743 6744 // If this is a friend or a reference to a class in a dependent 6745 // context, don't try to make a decl for it. 6746 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6747 DC = computeDeclContext(SS, false); 6748 if (!DC) { 6749 IsDependent = true; 6750 return 0; 6751 } 6752 } else { 6753 DC = computeDeclContext(SS, true); 6754 if (!DC) { 6755 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6756 << SS.getRange(); 6757 return 0; 6758 } 6759 } 6760 6761 if (RequireCompleteDeclContext(SS, DC)) 6762 return 0; 6763 6764 SearchDC = DC; 6765 // Look-up name inside 'foo::'. 6766 LookupQualifiedName(Previous, DC); 6767 6768 if (Previous.isAmbiguous()) 6769 return 0; 6770 6771 if (Previous.empty()) { 6772 // Name lookup did not find anything. However, if the 6773 // nested-name-specifier refers to the current instantiation, 6774 // and that current instantiation has any dependent base 6775 // classes, we might find something at instantiation time: treat 6776 // this as a dependent elaborated-type-specifier. 6777 // But this only makes any sense for reference-like lookups. 6778 if (Previous.wasNotFoundInCurrentInstantiation() && 6779 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6780 IsDependent = true; 6781 return 0; 6782 } 6783 6784 // A tag 'foo::bar' must already exist. 6785 Diag(NameLoc, diag::err_not_tag_in_scope) 6786 << Kind << Name << DC << SS.getRange(); 6787 Name = 0; 6788 Invalid = true; 6789 goto CreateNewDecl; 6790 } 6791 } else if (Name) { 6792 // If this is a named struct, check to see if there was a previous forward 6793 // declaration or definition. 6794 // FIXME: We're looking into outer scopes here, even when we 6795 // shouldn't be. Doing so can result in ambiguities that we 6796 // shouldn't be diagnosing. 6797 LookupName(Previous, S); 6798 6799 if (Previous.isAmbiguous() && 6800 (TUK == TUK_Definition || TUK == TUK_Declaration)) { 6801 LookupResult::Filter F = Previous.makeFilter(); 6802 while (F.hasNext()) { 6803 NamedDecl *ND = F.next(); 6804 if (ND->getDeclContext()->getRedeclContext() != SearchDC) 6805 F.erase(); 6806 } 6807 F.done(); 6808 } 6809 6810 // Note: there used to be some attempt at recovery here. 6811 if (Previous.isAmbiguous()) 6812 return 0; 6813 6814 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6815 // FIXME: This makes sure that we ignore the contexts associated 6816 // with C structs, unions, and enums when looking for a matching 6817 // tag declaration or definition. See the similar lookup tweak 6818 // in Sema::LookupName; is there a better way to deal with this? 6819 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 6820 SearchDC = SearchDC->getParent(); 6821 } 6822 } else if (S->isFunctionPrototypeScope()) { 6823 // If this is an enum declaration in function prototype scope, set its 6824 // initial context to the translation unit. 6825 SearchDC = Context.getTranslationUnitDecl(); 6826 } 6827 6828 if (Previous.isSingleResult() && 6829 Previous.getFoundDecl()->isTemplateParameter()) { 6830 // Maybe we will complain about the shadowed template parameter. 6831 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 6832 // Just pretend that we didn't see the previous declaration. 6833 Previous.clear(); 6834 } 6835 6836 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 6837 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 6838 // This is a declaration of or a reference to "std::bad_alloc". 6839 isStdBadAlloc = true; 6840 6841 if (Previous.empty() && StdBadAlloc) { 6842 // std::bad_alloc has been implicitly declared (but made invisible to 6843 // name lookup). Fill in this implicit declaration as the previous 6844 // declaration, so that the declarations get chained appropriately. 6845 Previous.addDecl(getStdBadAlloc()); 6846 } 6847 } 6848 6849 // If we didn't find a previous declaration, and this is a reference 6850 // (or friend reference), move to the correct scope. In C++, we 6851 // also need to do a redeclaration lookup there, just in case 6852 // there's a shadow friend decl. 6853 if (Name && Previous.empty() && 6854 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6855 if (Invalid) goto CreateNewDecl; 6856 assert(SS.isEmpty()); 6857 6858 if (TUK == TUK_Reference) { 6859 // C++ [basic.scope.pdecl]p5: 6860 // -- for an elaborated-type-specifier of the form 6861 // 6862 // class-key identifier 6863 // 6864 // if the elaborated-type-specifier is used in the 6865 // decl-specifier-seq or parameter-declaration-clause of a 6866 // function defined in namespace scope, the identifier is 6867 // declared as a class-name in the namespace that contains 6868 // the declaration; otherwise, except as a friend 6869 // declaration, the identifier is declared in the smallest 6870 // non-class, non-function-prototype scope that contains the 6871 // declaration. 6872 // 6873 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 6874 // C structs and unions. 6875 // 6876 // It is an error in C++ to declare (rather than define) an enum 6877 // type, including via an elaborated type specifier. We'll 6878 // diagnose that later; for now, declare the enum in the same 6879 // scope as we would have picked for any other tag type. 6880 // 6881 // GNU C also supports this behavior as part of its incomplete 6882 // enum types extension, while GNU C++ does not. 6883 // 6884 // Find the context where we'll be declaring the tag. 6885 // FIXME: We would like to maintain the current DeclContext as the 6886 // lexical context, 6887 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 6888 SearchDC = SearchDC->getParent(); 6889 6890 // Find the scope where we'll be declaring the tag. 6891 while (S->isClassScope() || 6892 (getLangOptions().CPlusPlus && 6893 S->isFunctionPrototypeScope()) || 6894 ((S->getFlags() & Scope::DeclScope) == 0) || 6895 (S->getEntity() && 6896 ((DeclContext *)S->getEntity())->isTransparentContext())) 6897 S = S->getParent(); 6898 } else { 6899 assert(TUK == TUK_Friend); 6900 // C++ [namespace.memdef]p3: 6901 // If a friend declaration in a non-local class first declares a 6902 // class or function, the friend class or function is a member of 6903 // the innermost enclosing namespace. 6904 SearchDC = SearchDC->getEnclosingNamespaceContext(); 6905 } 6906 6907 // In C++, we need to do a redeclaration lookup to properly 6908 // diagnose some problems. 6909 if (getLangOptions().CPlusPlus) { 6910 Previous.setRedeclarationKind(ForRedeclaration); 6911 LookupQualifiedName(Previous, SearchDC); 6912 } 6913 } 6914 6915 if (!Previous.empty()) { 6916 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 6917 6918 // It's okay to have a tag decl in the same scope as a typedef 6919 // which hides a tag decl in the same scope. Finding this 6920 // insanity with a redeclaration lookup can only actually happen 6921 // in C++. 6922 // 6923 // This is also okay for elaborated-type-specifiers, which is 6924 // technically forbidden by the current standard but which is 6925 // okay according to the likely resolution of an open issue; 6926 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 6927 if (getLangOptions().CPlusPlus) { 6928 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) { 6929 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 6930 TagDecl *Tag = TT->getDecl(); 6931 if (Tag->getDeclName() == Name && 6932 Tag->getDeclContext()->getRedeclContext() 6933 ->Equals(TD->getDeclContext()->getRedeclContext())) { 6934 PrevDecl = Tag; 6935 Previous.clear(); 6936 Previous.addDecl(Tag); 6937 Previous.resolveKind(); 6938 } 6939 } 6940 } 6941 } 6942 6943 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 6944 // If this is a use of a previous tag, or if the tag is already declared 6945 // in the same scope (so that the definition/declaration completes or 6946 // rementions the tag), reuse the decl. 6947 if (TUK == TUK_Reference || TUK == TUK_Friend || 6948 isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { 6949 // Make sure that this wasn't declared as an enum and now used as a 6950 // struct or something similar. 6951 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 6952 bool SafeToContinue 6953 = (PrevTagDecl->getTagKind() != TTK_Enum && 6954 Kind != TTK_Enum); 6955 if (SafeToContinue) 6956 Diag(KWLoc, diag::err_use_with_wrong_tag) 6957 << Name 6958 << FixItHint::CreateReplacement(SourceRange(KWLoc), 6959 PrevTagDecl->getKindName()); 6960 else 6961 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 6962 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6963 6964 if (SafeToContinue) 6965 Kind = PrevTagDecl->getTagKind(); 6966 else { 6967 // Recover by making this an anonymous redefinition. 6968 Name = 0; 6969 Previous.clear(); 6970 Invalid = true; 6971 } 6972 } 6973 6974 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 6975 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 6976 6977 // All conflicts with previous declarations are recovered by 6978 // returning the previous declaration. 6979 if (ScopedEnum != PrevEnum->isScoped()) { 6980 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 6981 << PrevEnum->isScoped(); 6982 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6983 return PrevTagDecl; 6984 } 6985 else if (EnumUnderlying && PrevEnum->isFixed()) { 6986 QualType T; 6987 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6988 T = TI->getType(); 6989 else 6990 T = QualType(EnumUnderlying.get<const Type*>(), 0); 6991 6992 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 6993 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 6994 diag::err_enum_redeclare_type_mismatch) 6995 << T 6996 << PrevEnum->getIntegerType(); 6997 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6998 return PrevTagDecl; 6999 } 7000 } 7001 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 7002 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 7003 << PrevEnum->isFixed(); 7004 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 7005 return PrevTagDecl; 7006 } 7007 } 7008 7009 if (!Invalid) { 7010 // If this is a use, just return the declaration we found. 7011 7012 // FIXME: In the future, return a variant or some other clue 7013 // for the consumer of this Decl to know it doesn't own it. 7014 // For our current ASTs this shouldn't be a problem, but will 7015 // need to be changed with DeclGroups. 7016 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 7017 TUK == TUK_Friend) 7018 return PrevTagDecl; 7019 7020 // Diagnose attempts to redefine a tag. 7021 if (TUK == TUK_Definition) { 7022 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 7023 // If we're defining a specialization and the previous definition 7024 // is from an implicit instantiation, don't emit an error 7025 // here; we'll catch this in the general case below. 7026 if (!isExplicitSpecialization || 7027 !isa<CXXRecordDecl>(Def) || 7028 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 7029 == TSK_ExplicitSpecialization) { 7030 Diag(NameLoc, diag::err_redefinition) << Name; 7031 Diag(Def->getLocation(), diag::note_previous_definition); 7032 // If this is a redefinition, recover by making this 7033 // struct be anonymous, which will make any later 7034 // references get the previous definition. 7035 Name = 0; 7036 Previous.clear(); 7037 Invalid = true; 7038 } 7039 } else { 7040 // If the type is currently being defined, complain 7041 // about a nested redefinition. 7042 const TagType *Tag 7043 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 7044 if (Tag->isBeingDefined()) { 7045 Diag(NameLoc, diag::err_nested_redefinition) << Name; 7046 Diag(PrevTagDecl->getLocation(), 7047 diag::note_previous_definition); 7048 Name = 0; 7049 Previous.clear(); 7050 Invalid = true; 7051 } 7052 } 7053 7054 // Okay, this is definition of a previously declared or referenced 7055 // tag PrevDecl. We're going to create a new Decl for it. 7056 } 7057 } 7058 // If we get here we have (another) forward declaration or we 7059 // have a definition. Just create a new decl. 7060 7061 } else { 7062 // If we get here, this is a definition of a new tag type in a nested 7063 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 7064 // new decl/type. We set PrevDecl to NULL so that the entities 7065 // have distinct types. 7066 Previous.clear(); 7067 } 7068 // If we get here, we're going to create a new Decl. If PrevDecl 7069 // is non-NULL, it's a definition of the tag declared by 7070 // PrevDecl. If it's NULL, we have a new definition. 7071 7072 7073 // Otherwise, PrevDecl is not a tag, but was found with tag 7074 // lookup. This is only actually possible in C++, where a few 7075 // things like templates still live in the tag namespace. 7076 } else { 7077 assert(getLangOptions().CPlusPlus); 7078 7079 // Use a better diagnostic if an elaborated-type-specifier 7080 // found the wrong kind of type on the first 7081 // (non-redeclaration) lookup. 7082 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 7083 !Previous.isForRedeclaration()) { 7084 unsigned Kind = 0; 7085 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 7086 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; 7087 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; 7088 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 7089 Diag(PrevDecl->getLocation(), diag::note_declared_at); 7090 Invalid = true; 7091 7092 // Otherwise, only diagnose if the declaration is in scope. 7093 } else if (!isDeclInScope(PrevDecl, SearchDC, S, 7094 isExplicitSpecialization)) { 7095 // do nothing 7096 7097 // Diagnose implicit declarations introduced by elaborated types. 7098 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 7099 unsigned Kind = 0; 7100 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 7101 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; 7102 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; 7103 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 7104 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 7105 Invalid = true; 7106 7107 // Otherwise it's a declaration. Call out a particularly common 7108 // case here. 7109 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) { 7110 unsigned Kind = 0; 7111 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1; 7112 Diag(NameLoc, diag::err_tag_definition_of_typedef) 7113 << Name << Kind << TND->getUnderlyingType(); 7114 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 7115 Invalid = true; 7116 7117 // Otherwise, diagnose. 7118 } else { 7119 // The tag name clashes with something else in the target scope, 7120 // issue an error and recover by making this tag be anonymous. 7121 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 7122 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7123 Name = 0; 7124 Invalid = true; 7125 } 7126 7127 // The existing declaration isn't relevant to us; we're in a 7128 // new scope, so clear out the previous declaration. 7129 Previous.clear(); 7130 } 7131 } 7132 7133CreateNewDecl: 7134 7135 TagDecl *PrevDecl = 0; 7136 if (Previous.isSingleResult()) 7137 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 7138 7139 // If there is an identifier, use the location of the identifier as the 7140 // location of the decl, otherwise use the location of the struct/union 7141 // keyword. 7142 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 7143 7144 // Otherwise, create a new declaration. If there is a previous 7145 // declaration of the same entity, the two will be linked via 7146 // PrevDecl. 7147 TagDecl *New; 7148 7149 bool IsForwardReference = false; 7150 if (Kind == TTK_Enum) { 7151 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 7152 // enum X { A, B, C } D; D should chain to X. 7153 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, 7154 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 7155 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 7156 // If this is an undefined enum, warn. 7157 if (TUK != TUK_Definition && !Invalid) { 7158 TagDecl *Def; 7159 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 7160 // C++0x: 7.2p2: opaque-enum-declaration. 7161 // Conflicts are diagnosed above. Do nothing. 7162 } 7163 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 7164 Diag(Loc, diag::ext_forward_ref_enum_def) 7165 << New; 7166 Diag(Def->getLocation(), diag::note_previous_definition); 7167 } else { 7168 unsigned DiagID = diag::ext_forward_ref_enum; 7169 if (getLangOptions().Microsoft) 7170 DiagID = diag::ext_ms_forward_ref_enum; 7171 else if (getLangOptions().CPlusPlus) 7172 DiagID = diag::err_forward_ref_enum; 7173 Diag(Loc, DiagID); 7174 7175 // If this is a forward-declared reference to an enumeration, make a 7176 // note of it; we won't actually be introducing the declaration into 7177 // the declaration context. 7178 if (TUK == TUK_Reference) 7179 IsForwardReference = true; 7180 } 7181 } 7182 7183 if (EnumUnderlying) { 7184 EnumDecl *ED = cast<EnumDecl>(New); 7185 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 7186 ED->setIntegerTypeSourceInfo(TI); 7187 else 7188 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 7189 ED->setPromotionType(ED->getIntegerType()); 7190 } 7191 7192 } else { 7193 // struct/union/class 7194 7195 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 7196 // struct X { int A; } D; D should chain to X. 7197 if (getLangOptions().CPlusPlus) { 7198 // FIXME: Look for a way to use RecordDecl for simple structs. 7199 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 7200 cast_or_null<CXXRecordDecl>(PrevDecl)); 7201 7202 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 7203 StdBadAlloc = cast<CXXRecordDecl>(New); 7204 } else 7205 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 7206 cast_or_null<RecordDecl>(PrevDecl)); 7207 } 7208 7209 // Maybe add qualifier info. 7210 if (SS.isNotEmpty()) { 7211 if (SS.isSet()) { 7212 New->setQualifierInfo(SS.getWithLocInContext(Context)); 7213 if (TemplateParameterLists.size() > 0) { 7214 New->setTemplateParameterListsInfo(Context, 7215 TemplateParameterLists.size(), 7216 (TemplateParameterList**) TemplateParameterLists.release()); 7217 } 7218 } 7219 else 7220 Invalid = true; 7221 } 7222 7223 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 7224 // Add alignment attributes if necessary; these attributes are checked when 7225 // the ASTContext lays out the structure. 7226 // 7227 // It is important for implementing the correct semantics that this 7228 // happen here (in act on tag decl). The #pragma pack stack is 7229 // maintained as a result of parser callbacks which can occur at 7230 // many points during the parsing of a struct declaration (because 7231 // the #pragma tokens are effectively skipped over during the 7232 // parsing of the struct). 7233 AddAlignmentAttributesForRecord(RD); 7234 7235 AddMsStructLayoutForRecord(RD); 7236 } 7237 7238 // If this is a specialization of a member class (of a class template), 7239 // check the specialization. 7240 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 7241 Invalid = true; 7242 7243 if (Invalid) 7244 New->setInvalidDecl(); 7245 7246 if (Attr) 7247 ProcessDeclAttributeList(S, New, Attr); 7248 7249 // If we're declaring or defining a tag in function prototype scope 7250 // in C, note that this type can only be used within the function. 7251 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 7252 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 7253 7254 // Set the lexical context. If the tag has a C++ scope specifier, the 7255 // lexical context will be different from the semantic context. 7256 New->setLexicalDeclContext(CurContext); 7257 7258 // Mark this as a friend decl if applicable. 7259 if (TUK == TUK_Friend) 7260 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 7261 7262 // Set the access specifier. 7263 if (!Invalid && SearchDC->isRecord()) 7264 SetMemberAccessSpecifier(New, PrevDecl, AS); 7265 7266 if (TUK == TUK_Definition) 7267 New->startDefinition(); 7268 7269 // If this has an identifier, add it to the scope stack. 7270 if (TUK == TUK_Friend) { 7271 // We might be replacing an existing declaration in the lookup tables; 7272 // if so, borrow its access specifier. 7273 if (PrevDecl) 7274 New->setAccess(PrevDecl->getAccess()); 7275 7276 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 7277 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 7278 if (Name) // can be null along some error paths 7279 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 7280 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 7281 } else if (Name) { 7282 S = getNonFieldDeclScope(S); 7283 PushOnScopeChains(New, S, !IsForwardReference); 7284 if (IsForwardReference) 7285 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 7286 7287 } else { 7288 CurContext->addDecl(New); 7289 } 7290 7291 // If this is the C FILE type, notify the AST context. 7292 if (IdentifierInfo *II = New->getIdentifier()) 7293 if (!New->isInvalidDecl() && 7294 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 7295 II->isStr("FILE")) 7296 Context.setFILEDecl(New); 7297 7298 OwnedDecl = true; 7299 return New; 7300} 7301 7302void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 7303 AdjustDeclIfTemplate(TagD); 7304 TagDecl *Tag = cast<TagDecl>(TagD); 7305 7306 // Enter the tag context. 7307 PushDeclContext(S, Tag); 7308} 7309 7310void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 7311 SourceLocation FinalLoc, 7312 SourceLocation LBraceLoc) { 7313 AdjustDeclIfTemplate(TagD); 7314 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 7315 7316 FieldCollector->StartClass(); 7317 7318 if (!Record->getIdentifier()) 7319 return; 7320 7321 if (FinalLoc.isValid()) 7322 Record->addAttr(new (Context) FinalAttr(FinalLoc, Context)); 7323 7324 // C++ [class]p2: 7325 // [...] The class-name is also inserted into the scope of the 7326 // class itself; this is known as the injected-class-name. For 7327 // purposes of access checking, the injected-class-name is treated 7328 // as if it were a public member name. 7329 CXXRecordDecl *InjectedClassName 7330 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, 7331 Record->getLocStart(), Record->getLocation(), 7332 Record->getIdentifier(), 7333 /*PrevDecl=*/0, 7334 /*DelayTypeCreation=*/true); 7335 Context.getTypeDeclType(InjectedClassName, Record); 7336 InjectedClassName->setImplicit(); 7337 InjectedClassName->setAccess(AS_public); 7338 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 7339 InjectedClassName->setDescribedClassTemplate(Template); 7340 PushOnScopeChains(InjectedClassName, S); 7341 assert(InjectedClassName->isInjectedClassName() && 7342 "Broken injected-class-name"); 7343} 7344 7345void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 7346 SourceLocation RBraceLoc) { 7347 AdjustDeclIfTemplate(TagD); 7348 TagDecl *Tag = cast<TagDecl>(TagD); 7349 Tag->setRBraceLoc(RBraceLoc); 7350 7351 if (isa<CXXRecordDecl>(Tag)) 7352 FieldCollector->FinishClass(); 7353 7354 // Exit this scope of this tag's definition. 7355 PopDeclContext(); 7356 7357 // Notify the consumer that we've defined a tag. 7358 Consumer.HandleTagDeclDefinition(Tag); 7359} 7360 7361void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 7362 AdjustDeclIfTemplate(TagD); 7363 TagDecl *Tag = cast<TagDecl>(TagD); 7364 Tag->setInvalidDecl(); 7365 7366 // We're undoing ActOnTagStartDefinition here, not 7367 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 7368 // the FieldCollector. 7369 7370 PopDeclContext(); 7371} 7372 7373// Note that FieldName may be null for anonymous bitfields. 7374bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 7375 QualType FieldTy, const Expr *BitWidth, 7376 bool *ZeroWidth) { 7377 // Default to true; that shouldn't confuse checks for emptiness 7378 if (ZeroWidth) 7379 *ZeroWidth = true; 7380 7381 // C99 6.7.2.1p4 - verify the field type. 7382 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 7383 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 7384 // Handle incomplete types with specific error. 7385 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 7386 return true; 7387 if (FieldName) 7388 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 7389 << FieldName << FieldTy << BitWidth->getSourceRange(); 7390 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 7391 << FieldTy << BitWidth->getSourceRange(); 7392 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 7393 UPPC_BitFieldWidth)) 7394 return true; 7395 7396 // If the bit-width is type- or value-dependent, don't try to check 7397 // it now. 7398 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 7399 return false; 7400 7401 llvm::APSInt Value; 7402 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 7403 return true; 7404 7405 if (Value != 0 && ZeroWidth) 7406 *ZeroWidth = false; 7407 7408 // Zero-width bitfield is ok for anonymous field. 7409 if (Value == 0 && FieldName) 7410 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 7411 7412 if (Value.isSigned() && Value.isNegative()) { 7413 if (FieldName) 7414 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 7415 << FieldName << Value.toString(10); 7416 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 7417 << Value.toString(10); 7418 } 7419 7420 if (!FieldTy->isDependentType()) { 7421 uint64_t TypeSize = Context.getTypeSize(FieldTy); 7422 if (Value.getZExtValue() > TypeSize) { 7423 if (!getLangOptions().CPlusPlus) { 7424 if (FieldName) 7425 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 7426 << FieldName << (unsigned)Value.getZExtValue() 7427 << (unsigned)TypeSize; 7428 7429 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 7430 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 7431 } 7432 7433 if (FieldName) 7434 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 7435 << FieldName << (unsigned)Value.getZExtValue() 7436 << (unsigned)TypeSize; 7437 else 7438 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 7439 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 7440 } 7441 } 7442 7443 return false; 7444} 7445 7446/// ActOnField - Each field of a struct/union/class is passed into this in order 7447/// to create a FieldDecl object for it. 7448Decl *Sema::ActOnField(Scope *S, Decl *TagD, 7449 SourceLocation DeclStart, 7450 Declarator &D, ExprTy *BitfieldWidth) { 7451 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 7452 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 7453 AS_public); 7454 return Res; 7455} 7456 7457/// HandleField - Analyze a field of a C struct or a C++ data member. 7458/// 7459FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 7460 SourceLocation DeclStart, 7461 Declarator &D, Expr *BitWidth, 7462 AccessSpecifier AS) { 7463 IdentifierInfo *II = D.getIdentifier(); 7464 SourceLocation Loc = DeclStart; 7465 if (II) Loc = D.getIdentifierLoc(); 7466 7467 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7468 QualType T = TInfo->getType(); 7469 if (getLangOptions().CPlusPlus) { 7470 CheckExtraCXXDefaultArguments(D); 7471 7472 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 7473 UPPC_DataMemberType)) { 7474 D.setInvalidType(); 7475 T = Context.IntTy; 7476 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 7477 } 7478 } 7479 7480 DiagnoseFunctionSpecifiers(D); 7481 7482 if (D.getDeclSpec().isThreadSpecified()) 7483 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 7484 7485 // Check to see if this name was declared as a member previously 7486 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 7487 LookupName(Previous, S); 7488 assert((Previous.empty() || Previous.isOverloadedResult() || 7489 Previous.isSingleResult()) 7490 && "Lookup of member name should be either overloaded, single or null"); 7491 7492 // If the name is overloaded then get any declaration else get the single result 7493 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 7494 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 7495 7496 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7497 // Maybe we will complain about the shadowed template parameter. 7498 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 7499 // Just pretend that we didn't see the previous declaration. 7500 PrevDecl = 0; 7501 } 7502 7503 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 7504 PrevDecl = 0; 7505 7506 bool Mutable 7507 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 7508 SourceLocation TSSL = D.getSourceRange().getBegin(); 7509 FieldDecl *NewFD 7510 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 7511 AS, PrevDecl, &D); 7512 7513 if (NewFD->isInvalidDecl()) 7514 Record->setInvalidDecl(); 7515 7516 if (NewFD->isInvalidDecl() && PrevDecl) { 7517 // Don't introduce NewFD into scope; there's already something 7518 // with the same name in the same scope. 7519 } else if (II) { 7520 PushOnScopeChains(NewFD, S); 7521 } else 7522 Record->addDecl(NewFD); 7523 7524 return NewFD; 7525} 7526 7527/// \brief Build a new FieldDecl and check its well-formedness. 7528/// 7529/// This routine builds a new FieldDecl given the fields name, type, 7530/// record, etc. \p PrevDecl should refer to any previous declaration 7531/// with the same name and in the same scope as the field to be 7532/// created. 7533/// 7534/// \returns a new FieldDecl. 7535/// 7536/// \todo The Declarator argument is a hack. It will be removed once 7537FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 7538 TypeSourceInfo *TInfo, 7539 RecordDecl *Record, SourceLocation Loc, 7540 bool Mutable, Expr *BitWidth, 7541 SourceLocation TSSL, 7542 AccessSpecifier AS, NamedDecl *PrevDecl, 7543 Declarator *D) { 7544 IdentifierInfo *II = Name.getAsIdentifierInfo(); 7545 bool InvalidDecl = false; 7546 if (D) InvalidDecl = D->isInvalidType(); 7547 7548 // If we receive a broken type, recover by assuming 'int' and 7549 // marking this declaration as invalid. 7550 if (T.isNull()) { 7551 InvalidDecl = true; 7552 T = Context.IntTy; 7553 } 7554 7555 QualType EltTy = Context.getBaseElementType(T); 7556 if (!EltTy->isDependentType() && 7557 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 7558 // Fields of incomplete type force their record to be invalid. 7559 Record->setInvalidDecl(); 7560 InvalidDecl = true; 7561 } 7562 7563 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7564 // than a variably modified type. 7565 if (!InvalidDecl && T->isVariablyModifiedType()) { 7566 bool SizeIsNegative; 7567 llvm::APSInt Oversized; 7568 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 7569 SizeIsNegative, 7570 Oversized); 7571 if (!FixedTy.isNull()) { 7572 Diag(Loc, diag::warn_illegal_constant_array_size); 7573 T = FixedTy; 7574 } else { 7575 if (SizeIsNegative) 7576 Diag(Loc, diag::err_typecheck_negative_array_size); 7577 else if (Oversized.getBoolValue()) 7578 Diag(Loc, diag::err_array_too_large) 7579 << Oversized.toString(10); 7580 else 7581 Diag(Loc, diag::err_typecheck_field_variable_size); 7582 InvalidDecl = true; 7583 } 7584 } 7585 7586 // Fields can not have abstract class types 7587 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 7588 diag::err_abstract_type_in_decl, 7589 AbstractFieldType)) 7590 InvalidDecl = true; 7591 7592 bool ZeroWidth = false; 7593 // If this is declared as a bit-field, check the bit-field. 7594 if (!InvalidDecl && BitWidth && 7595 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 7596 InvalidDecl = true; 7597 BitWidth = 0; 7598 ZeroWidth = false; 7599 } 7600 7601 // Check that 'mutable' is consistent with the type of the declaration. 7602 if (!InvalidDecl && Mutable) { 7603 unsigned DiagID = 0; 7604 if (T->isReferenceType()) 7605 DiagID = diag::err_mutable_reference; 7606 else if (T.isConstQualified()) 7607 DiagID = diag::err_mutable_const; 7608 7609 if (DiagID) { 7610 SourceLocation ErrLoc = Loc; 7611 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 7612 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 7613 Diag(ErrLoc, DiagID); 7614 Mutable = false; 7615 InvalidDecl = true; 7616 } 7617 } 7618 7619 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, 7620 BitWidth, Mutable); 7621 if (InvalidDecl) 7622 NewFD->setInvalidDecl(); 7623 7624 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 7625 Diag(Loc, diag::err_duplicate_member) << II; 7626 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7627 NewFD->setInvalidDecl(); 7628 } 7629 7630 if (!InvalidDecl && getLangOptions().CPlusPlus) { 7631 if (Record->isUnion()) { 7632 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7633 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7634 if (RDecl->getDefinition()) { 7635 // C++ [class.union]p1: An object of a class with a non-trivial 7636 // constructor, a non-trivial copy constructor, a non-trivial 7637 // destructor, or a non-trivial copy assignment operator 7638 // cannot be a member of a union, nor can an array of such 7639 // objects. 7640 if (!getLangOptions().CPlusPlus0x && CheckNontrivialField(NewFD)) 7641 NewFD->setInvalidDecl(); 7642 } 7643 } 7644 7645 // C++ [class.union]p1: If a union contains a member of reference type, 7646 // the program is ill-formed. 7647 if (EltTy->isReferenceType()) { 7648 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 7649 << NewFD->getDeclName() << EltTy; 7650 NewFD->setInvalidDecl(); 7651 } 7652 } 7653 } 7654 7655 // FIXME: We need to pass in the attributes given an AST 7656 // representation, not a parser representation. 7657 if (D) 7658 // FIXME: What to pass instead of TUScope? 7659 ProcessDeclAttributes(TUScope, NewFD, *D); 7660 7661 if (T.isObjCGCWeak()) 7662 Diag(Loc, diag::warn_attribute_weak_on_field); 7663 7664 NewFD->setAccess(AS); 7665 return NewFD; 7666} 7667 7668bool Sema::CheckNontrivialField(FieldDecl *FD) { 7669 assert(FD); 7670 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 7671 7672 if (FD->isInvalidDecl()) 7673 return true; 7674 7675 QualType EltTy = Context.getBaseElementType(FD->getType()); 7676 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7677 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7678 if (RDecl->getDefinition()) { 7679 // We check for copy constructors before constructors 7680 // because otherwise we'll never get complaints about 7681 // copy constructors. 7682 7683 CXXSpecialMember member = CXXInvalid; 7684 if (!RDecl->hasTrivialCopyConstructor()) 7685 member = CXXCopyConstructor; 7686 else if (!RDecl->hasTrivialDefaultConstructor()) 7687 member = CXXDefaultConstructor; 7688 else if (!RDecl->hasTrivialCopyAssignment()) 7689 member = CXXCopyAssignment; 7690 else if (!RDecl->hasTrivialDestructor()) 7691 member = CXXDestructor; 7692 7693 if (member != CXXInvalid) { 7694 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7695 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7696 DiagnoseNontrivial(RT, member); 7697 return true; 7698 } 7699 } 7700 } 7701 7702 return false; 7703} 7704 7705/// DiagnoseNontrivial - Given that a class has a non-trivial 7706/// special member, figure out why. 7707void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7708 QualType QT(T, 0U); 7709 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7710 7711 // Check whether the member was user-declared. 7712 switch (member) { 7713 case CXXInvalid: 7714 break; 7715 7716 case CXXDefaultConstructor: 7717 if (RD->hasUserDeclaredConstructor()) { 7718 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7719 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7720 const FunctionDecl *body = 0; 7721 ci->hasBody(body); 7722 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7723 SourceLocation CtorLoc = ci->getLocation(); 7724 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7725 return; 7726 } 7727 } 7728 7729 assert(0 && "found no user-declared constructors"); 7730 return; 7731 } 7732 break; 7733 7734 case CXXCopyConstructor: 7735 if (RD->hasUserDeclaredCopyConstructor()) { 7736 SourceLocation CtorLoc = 7737 RD->getCopyConstructor(Context, 0)->getLocation(); 7738 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7739 return; 7740 } 7741 break; 7742 7743 case CXXCopyAssignment: 7744 if (RD->hasUserDeclaredCopyAssignment()) { 7745 // FIXME: this should use the location of the copy 7746 // assignment, not the type. 7747 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7748 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7749 return; 7750 } 7751 break; 7752 7753 case CXXDestructor: 7754 if (RD->hasUserDeclaredDestructor()) { 7755 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7756 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7757 return; 7758 } 7759 break; 7760 } 7761 7762 typedef CXXRecordDecl::base_class_iterator base_iter; 7763 7764 // Virtual bases and members inhibit trivial copying/construction, 7765 // but not trivial destruction. 7766 if (member != CXXDestructor) { 7767 // Check for virtual bases. vbases includes indirect virtual bases, 7768 // so we just iterate through the direct bases. 7769 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7770 if (bi->isVirtual()) { 7771 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7772 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7773 return; 7774 } 7775 7776 // Check for virtual methods. 7777 typedef CXXRecordDecl::method_iterator meth_iter; 7778 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 7779 ++mi) { 7780 if (mi->isVirtual()) { 7781 SourceLocation MLoc = mi->getSourceRange().getBegin(); 7782 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 7783 return; 7784 } 7785 } 7786 } 7787 7788 bool (CXXRecordDecl::*hasTrivial)() const; 7789 switch (member) { 7790 case CXXDefaultConstructor: 7791 hasTrivial = &CXXRecordDecl::hasTrivialDefaultConstructor; break; 7792 case CXXCopyConstructor: 7793 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 7794 case CXXCopyAssignment: 7795 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 7796 case CXXDestructor: 7797 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 7798 default: 7799 assert(0 && "unexpected special member"); return; 7800 } 7801 7802 // Check for nontrivial bases (and recurse). 7803 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 7804 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 7805 assert(BaseRT && "Don't know how to handle dependent bases"); 7806 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 7807 if (!(BaseRecTy->*hasTrivial)()) { 7808 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7809 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 7810 DiagnoseNontrivial(BaseRT, member); 7811 return; 7812 } 7813 } 7814 7815 // Check for nontrivial members (and recurse). 7816 typedef RecordDecl::field_iterator field_iter; 7817 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 7818 ++fi) { 7819 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 7820 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 7821 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 7822 7823 if (!(EltRD->*hasTrivial)()) { 7824 SourceLocation FLoc = (*fi)->getLocation(); 7825 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 7826 DiagnoseNontrivial(EltRT, member); 7827 return; 7828 } 7829 } 7830 } 7831 7832 assert(0 && "found no explanation for non-trivial member"); 7833} 7834 7835/// TranslateIvarVisibility - Translate visibility from a token ID to an 7836/// AST enum value. 7837static ObjCIvarDecl::AccessControl 7838TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 7839 switch (ivarVisibility) { 7840 default: assert(0 && "Unknown visitibility kind"); 7841 case tok::objc_private: return ObjCIvarDecl::Private; 7842 case tok::objc_public: return ObjCIvarDecl::Public; 7843 case tok::objc_protected: return ObjCIvarDecl::Protected; 7844 case tok::objc_package: return ObjCIvarDecl::Package; 7845 } 7846} 7847 7848/// ActOnIvar - Each ivar field of an objective-c class is passed into this 7849/// in order to create an IvarDecl object for it. 7850Decl *Sema::ActOnIvar(Scope *S, 7851 SourceLocation DeclStart, 7852 Decl *IntfDecl, 7853 Declarator &D, ExprTy *BitfieldWidth, 7854 tok::ObjCKeywordKind Visibility) { 7855 7856 IdentifierInfo *II = D.getIdentifier(); 7857 Expr *BitWidth = (Expr*)BitfieldWidth; 7858 SourceLocation Loc = DeclStart; 7859 if (II) Loc = D.getIdentifierLoc(); 7860 7861 // FIXME: Unnamed fields can be handled in various different ways, for 7862 // example, unnamed unions inject all members into the struct namespace! 7863 7864 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7865 QualType T = TInfo->getType(); 7866 7867 if (BitWidth) { 7868 // 6.7.2.1p3, 6.7.2.1p4 7869 if (VerifyBitField(Loc, II, T, BitWidth)) { 7870 D.setInvalidType(); 7871 BitWidth = 0; 7872 } 7873 } else { 7874 // Not a bitfield. 7875 7876 // validate II. 7877 7878 } 7879 if (T->isReferenceType()) { 7880 Diag(Loc, diag::err_ivar_reference_type); 7881 D.setInvalidType(); 7882 } 7883 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7884 // than a variably modified type. 7885 else if (T->isVariablyModifiedType()) { 7886 Diag(Loc, diag::err_typecheck_ivar_variable_size); 7887 D.setInvalidType(); 7888 } 7889 7890 // Get the visibility (access control) for this ivar. 7891 ObjCIvarDecl::AccessControl ac = 7892 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 7893 : ObjCIvarDecl::None; 7894 // Must set ivar's DeclContext to its enclosing interface. 7895 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 7896 ObjCContainerDecl *EnclosingContext; 7897 if (ObjCImplementationDecl *IMPDecl = 7898 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7899 if (!LangOpts.ObjCNonFragileABI2) { 7900 // Case of ivar declared in an implementation. Context is that of its class. 7901 EnclosingContext = IMPDecl->getClassInterface(); 7902 assert(EnclosingContext && "Implementation has no class interface!"); 7903 } 7904 else 7905 EnclosingContext = EnclosingDecl; 7906 } else { 7907 if (ObjCCategoryDecl *CDecl = 7908 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7909 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 7910 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 7911 return 0; 7912 } 7913 } 7914 EnclosingContext = EnclosingDecl; 7915 } 7916 7917 // Construct the decl. 7918 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, 7919 DeclStart, Loc, II, T, 7920 TInfo, ac, (Expr *)BitfieldWidth); 7921 7922 if (II) { 7923 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 7924 ForRedeclaration); 7925 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 7926 && !isa<TagDecl>(PrevDecl)) { 7927 Diag(Loc, diag::err_duplicate_member) << II; 7928 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7929 NewID->setInvalidDecl(); 7930 } 7931 } 7932 7933 // Process attributes attached to the ivar. 7934 ProcessDeclAttributes(S, NewID, D); 7935 7936 if (D.isInvalidType()) 7937 NewID->setInvalidDecl(); 7938 7939 if (II) { 7940 // FIXME: When interfaces are DeclContexts, we'll need to add 7941 // these to the interface. 7942 S->AddDecl(NewID); 7943 IdResolver.AddDecl(NewID); 7944 } 7945 7946 return NewID; 7947} 7948 7949/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 7950/// class and class extensions. For every class @interface and class 7951/// extension @interface, if the last ivar is a bitfield of any type, 7952/// then add an implicit `char :0` ivar to the end of that interface. 7953void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 7954 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 7955 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 7956 return; 7957 7958 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 7959 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 7960 7961 if (!Ivar->isBitField()) 7962 return; 7963 uint64_t BitFieldSize = 7964 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 7965 if (BitFieldSize == 0) 7966 return; 7967 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 7968 if (!ID) { 7969 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7970 if (!CD->IsClassExtension()) 7971 return; 7972 } 7973 // No need to add this to end of @implementation. 7974 else 7975 return; 7976 } 7977 // All conditions are met. Add a new bitfield to the tail end of ivars. 7978 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 7979 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 7980 7981 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 7982 DeclLoc, DeclLoc, 0, 7983 Context.CharTy, 7984 Context.CreateTypeSourceInfo(Context.CharTy), 7985 ObjCIvarDecl::Private, BW, 7986 true); 7987 AllIvarDecls.push_back(Ivar); 7988} 7989 7990void Sema::ActOnFields(Scope* S, 7991 SourceLocation RecLoc, Decl *EnclosingDecl, 7992 Decl **Fields, unsigned NumFields, 7993 SourceLocation LBrac, SourceLocation RBrac, 7994 AttributeList *Attr) { 7995 assert(EnclosingDecl && "missing record or interface decl"); 7996 7997 // If the decl this is being inserted into is invalid, then it may be a 7998 // redeclaration or some other bogus case. Don't try to add fields to it. 7999 if (EnclosingDecl->isInvalidDecl()) { 8000 // FIXME: Deallocate fields? 8001 return; 8002 } 8003 8004 8005 // Verify that all the fields are okay. 8006 unsigned NumNamedMembers = 0; 8007 llvm::SmallVector<FieldDecl*, 32> RecFields; 8008 8009 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 8010 for (unsigned i = 0; i != NumFields; ++i) { 8011 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 8012 8013 // Get the type for the field. 8014 const Type *FDTy = FD->getType().getTypePtr(); 8015 8016 if (!FD->isAnonymousStructOrUnion()) { 8017 // Remember all fields written by the user. 8018 RecFields.push_back(FD); 8019 } 8020 8021 // If the field is already invalid for some reason, don't emit more 8022 // diagnostics about it. 8023 if (FD->isInvalidDecl()) { 8024 EnclosingDecl->setInvalidDecl(); 8025 continue; 8026 } 8027 8028 // C99 6.7.2.1p2: 8029 // A structure or union shall not contain a member with 8030 // incomplete or function type (hence, a structure shall not 8031 // contain an instance of itself, but may contain a pointer to 8032 // an instance of itself), except that the last member of a 8033 // structure with more than one named member may have incomplete 8034 // array type; such a structure (and any union containing, 8035 // possibly recursively, a member that is such a structure) 8036 // shall not be a member of a structure or an element of an 8037 // array. 8038 if (FDTy->isFunctionType()) { 8039 // Field declared as a function. 8040 Diag(FD->getLocation(), diag::err_field_declared_as_function) 8041 << FD->getDeclName(); 8042 FD->setInvalidDecl(); 8043 EnclosingDecl->setInvalidDecl(); 8044 continue; 8045 } else if (FDTy->isIncompleteArrayType() && Record && 8046 ((i == NumFields - 1 && !Record->isUnion()) || 8047 ((getLangOptions().Microsoft || getLangOptions().CPlusPlus) && 8048 (i == NumFields - 1 || Record->isUnion())))) { 8049 // Flexible array member. 8050 // Microsoft and g++ is more permissive regarding flexible array. 8051 // It will accept flexible array in union and also 8052 // as the sole element of a struct/class. 8053 if (getLangOptions().Microsoft) { 8054 if (Record->isUnion()) 8055 Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) 8056 << FD->getDeclName(); 8057 else if (NumFields == 1) 8058 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) 8059 << FD->getDeclName() << Record->getTagKind(); 8060 } else if (getLangOptions().CPlusPlus) { 8061 if (Record->isUnion()) 8062 Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) 8063 << FD->getDeclName(); 8064 else if (NumFields == 1) 8065 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) 8066 << FD->getDeclName() << Record->getTagKind(); 8067 } else if (NumNamedMembers < 1) { 8068 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 8069 << FD->getDeclName(); 8070 FD->setInvalidDecl(); 8071 EnclosingDecl->setInvalidDecl(); 8072 continue; 8073 } 8074 if (!FD->getType()->isDependentType() && 8075 !Context.getBaseElementType(FD->getType())->isPODType()) { 8076 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 8077 << FD->getDeclName() << FD->getType(); 8078 FD->setInvalidDecl(); 8079 EnclosingDecl->setInvalidDecl(); 8080 continue; 8081 } 8082 // Okay, we have a legal flexible array member at the end of the struct. 8083 if (Record) 8084 Record->setHasFlexibleArrayMember(true); 8085 } else if (!FDTy->isDependentType() && 8086 RequireCompleteType(FD->getLocation(), FD->getType(), 8087 diag::err_field_incomplete)) { 8088 // Incomplete type 8089 FD->setInvalidDecl(); 8090 EnclosingDecl->setInvalidDecl(); 8091 continue; 8092 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 8093 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 8094 // If this is a member of a union, then entire union becomes "flexible". 8095 if (Record && Record->isUnion()) { 8096 Record->setHasFlexibleArrayMember(true); 8097 } else { 8098 // If this is a struct/class and this is not the last element, reject 8099 // it. Note that GCC supports variable sized arrays in the middle of 8100 // structures. 8101 if (i != NumFields-1) 8102 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 8103 << FD->getDeclName() << FD->getType(); 8104 else { 8105 // We support flexible arrays at the end of structs in 8106 // other structs as an extension. 8107 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 8108 << FD->getDeclName(); 8109 if (Record) 8110 Record->setHasFlexibleArrayMember(true); 8111 } 8112 } 8113 } 8114 if (Record && FDTTy->getDecl()->hasObjectMember()) 8115 Record->setHasObjectMember(true); 8116 } else if (FDTy->isObjCObjectType()) { 8117 /// A field cannot be an Objective-c object 8118 Diag(FD->getLocation(), diag::err_statically_allocated_object); 8119 FD->setInvalidDecl(); 8120 EnclosingDecl->setInvalidDecl(); 8121 continue; 8122 } else if (getLangOptions().ObjC1 && 8123 getLangOptions().getGCMode() != LangOptions::NonGC && 8124 Record && 8125 (FD->getType()->isObjCObjectPointerType() || 8126 FD->getType().isObjCGCStrong())) 8127 Record->setHasObjectMember(true); 8128 else if (Context.getAsArrayType(FD->getType())) { 8129 QualType BaseType = Context.getBaseElementType(FD->getType()); 8130 if (Record && BaseType->isRecordType() && 8131 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 8132 Record->setHasObjectMember(true); 8133 } 8134 // Keep track of the number of named members. 8135 if (FD->getIdentifier()) 8136 ++NumNamedMembers; 8137 } 8138 8139 // Okay, we successfully defined 'Record'. 8140 if (Record) { 8141 bool Completed = false; 8142 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 8143 if (!CXXRecord->isInvalidDecl()) { 8144 // Set access bits correctly on the directly-declared conversions. 8145 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 8146 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 8147 I != E; ++I) 8148 Convs->setAccess(I, (*I)->getAccess()); 8149 8150 if (!CXXRecord->isDependentType()) { 8151 // Adjust user-defined destructor exception spec. 8152 if (getLangOptions().CPlusPlus0x && 8153 CXXRecord->hasUserDeclaredDestructor()) 8154 AdjustDestructorExceptionSpec(CXXRecord,CXXRecord->getDestructor()); 8155 8156 // Add any implicitly-declared members to this class. 8157 AddImplicitlyDeclaredMembersToClass(CXXRecord); 8158 8159 // If we have virtual base classes, we may end up finding multiple 8160 // final overriders for a given virtual function. Check for this 8161 // problem now. 8162 if (CXXRecord->getNumVBases()) { 8163 CXXFinalOverriderMap FinalOverriders; 8164 CXXRecord->getFinalOverriders(FinalOverriders); 8165 8166 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 8167 MEnd = FinalOverriders.end(); 8168 M != MEnd; ++M) { 8169 for (OverridingMethods::iterator SO = M->second.begin(), 8170 SOEnd = M->second.end(); 8171 SO != SOEnd; ++SO) { 8172 assert(SO->second.size() > 0 && 8173 "Virtual function without overridding functions?"); 8174 if (SO->second.size() == 1) 8175 continue; 8176 8177 // C++ [class.virtual]p2: 8178 // In a derived class, if a virtual member function of a base 8179 // class subobject has more than one final overrider the 8180 // program is ill-formed. 8181 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 8182 << (NamedDecl *)M->first << Record; 8183 Diag(M->first->getLocation(), 8184 diag::note_overridden_virtual_function); 8185 for (OverridingMethods::overriding_iterator 8186 OM = SO->second.begin(), 8187 OMEnd = SO->second.end(); 8188 OM != OMEnd; ++OM) 8189 Diag(OM->Method->getLocation(), diag::note_final_overrider) 8190 << (NamedDecl *)M->first << OM->Method->getParent(); 8191 8192 Record->setInvalidDecl(); 8193 } 8194 } 8195 CXXRecord->completeDefinition(&FinalOverriders); 8196 Completed = true; 8197 } 8198 } 8199 } 8200 } 8201 8202 if (!Completed) 8203 Record->completeDefinition(); 8204 8205 // Now that the record is complete, do any delayed exception spec checks 8206 // we were missing. 8207 if (!DelayedDestructorExceptionSpecChecks.empty()) { 8208 const CXXDestructorDecl *Dtor = 8209 DelayedDestructorExceptionSpecChecks.back().first; 8210 if (Dtor->getParent() == Record) { 8211 assert(!Dtor->getParent()->isDependentType() && 8212 "Should not ever add destructors of templates into the list."); 8213 CheckOverridingFunctionExceptionSpec(Dtor, 8214 DelayedDestructorExceptionSpecChecks.back().second); 8215 DelayedDestructorExceptionSpecChecks.pop_back(); 8216 } 8217 } 8218 8219 } else { 8220 ObjCIvarDecl **ClsFields = 8221 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 8222 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 8223 ID->setLocEnd(RBrac); 8224 // Add ivar's to class's DeclContext. 8225 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 8226 ClsFields[i]->setLexicalDeclContext(ID); 8227 ID->addDecl(ClsFields[i]); 8228 } 8229 // Must enforce the rule that ivars in the base classes may not be 8230 // duplicates. 8231 if (ID->getSuperClass()) 8232 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 8233 } else if (ObjCImplementationDecl *IMPDecl = 8234 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 8235 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 8236 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 8237 // Ivar declared in @implementation never belongs to the implementation. 8238 // Only it is in implementation's lexical context. 8239 ClsFields[I]->setLexicalDeclContext(IMPDecl); 8240 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 8241 } else if (ObjCCategoryDecl *CDecl = 8242 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 8243 // case of ivars in class extension; all other cases have been 8244 // reported as errors elsewhere. 8245 // FIXME. Class extension does not have a LocEnd field. 8246 // CDecl->setLocEnd(RBrac); 8247 // Add ivar's to class extension's DeclContext. 8248 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 8249 ClsFields[i]->setLexicalDeclContext(CDecl); 8250 CDecl->addDecl(ClsFields[i]); 8251 } 8252 } 8253 } 8254 8255 if (Attr) 8256 ProcessDeclAttributeList(S, Record, Attr); 8257 8258 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 8259 // set the visibility of this record. 8260 if (Record && !Record->getDeclContext()->isRecord()) 8261 AddPushedVisibilityAttribute(Record); 8262} 8263 8264/// \brief Determine whether the given integral value is representable within 8265/// the given type T. 8266static bool isRepresentableIntegerValue(ASTContext &Context, 8267 llvm::APSInt &Value, 8268 QualType T) { 8269 assert(T->isIntegralType(Context) && "Integral type required!"); 8270 unsigned BitWidth = Context.getIntWidth(T); 8271 8272 if (Value.isUnsigned() || Value.isNonNegative()) { 8273 if (T->isSignedIntegerOrEnumerationType()) 8274 --BitWidth; 8275 return Value.getActiveBits() <= BitWidth; 8276 } 8277 return Value.getMinSignedBits() <= BitWidth; 8278} 8279 8280// \brief Given an integral type, return the next larger integral type 8281// (or a NULL type of no such type exists). 8282static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 8283 // FIXME: Int128/UInt128 support, which also needs to be introduced into 8284 // enum checking below. 8285 assert(T->isIntegralType(Context) && "Integral type required!"); 8286 const unsigned NumTypes = 4; 8287 QualType SignedIntegralTypes[NumTypes] = { 8288 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 8289 }; 8290 QualType UnsignedIntegralTypes[NumTypes] = { 8291 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 8292 Context.UnsignedLongLongTy 8293 }; 8294 8295 unsigned BitWidth = Context.getTypeSize(T); 8296 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes 8297 : UnsignedIntegralTypes; 8298 for (unsigned I = 0; I != NumTypes; ++I) 8299 if (Context.getTypeSize(Types[I]) > BitWidth) 8300 return Types[I]; 8301 8302 return QualType(); 8303} 8304 8305EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 8306 EnumConstantDecl *LastEnumConst, 8307 SourceLocation IdLoc, 8308 IdentifierInfo *Id, 8309 Expr *Val) { 8310 unsigned IntWidth = Context.Target.getIntWidth(); 8311 llvm::APSInt EnumVal(IntWidth); 8312 QualType EltTy; 8313 8314 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 8315 Val = 0; 8316 8317 if (Val) { 8318 if (Enum->isDependentType() || Val->isTypeDependent()) 8319 EltTy = Context.DependentTy; 8320 else { 8321 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 8322 SourceLocation ExpLoc; 8323 if (!Val->isValueDependent() && 8324 VerifyIntegerConstantExpression(Val, &EnumVal)) { 8325 Val = 0; 8326 } else { 8327 if (!getLangOptions().CPlusPlus) { 8328 // C99 6.7.2.2p2: 8329 // The expression that defines the value of an enumeration constant 8330 // shall be an integer constant expression that has a value 8331 // representable as an int. 8332 8333 // Complain if the value is not representable in an int. 8334 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 8335 Diag(IdLoc, diag::ext_enum_value_not_int) 8336 << EnumVal.toString(10) << Val->getSourceRange() 8337 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 8338 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 8339 // Force the type of the expression to 'int'. 8340 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).take(); 8341 } 8342 } 8343 8344 if (Enum->isFixed()) { 8345 EltTy = Enum->getIntegerType(); 8346 8347 // C++0x [dcl.enum]p5: 8348 // ... if the initializing value of an enumerator cannot be 8349 // represented by the underlying type, the program is ill-formed. 8350 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 8351 if (getLangOptions().Microsoft) { 8352 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 8353 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 8354 } else 8355 Diag(IdLoc, diag::err_enumerator_too_large) 8356 << EltTy; 8357 } else 8358 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 8359 } 8360 else { 8361 // C++0x [dcl.enum]p5: 8362 // If the underlying type is not fixed, the type of each enumerator 8363 // is the type of its initializing value: 8364 // - If an initializer is specified for an enumerator, the 8365 // initializing value has the same type as the expression. 8366 EltTy = Val->getType(); 8367 } 8368 } 8369 } 8370 } 8371 8372 if (!Val) { 8373 if (Enum->isDependentType()) 8374 EltTy = Context.DependentTy; 8375 else if (!LastEnumConst) { 8376 // C++0x [dcl.enum]p5: 8377 // If the underlying type is not fixed, the type of each enumerator 8378 // is the type of its initializing value: 8379 // - If no initializer is specified for the first enumerator, the 8380 // initializing value has an unspecified integral type. 8381 // 8382 // GCC uses 'int' for its unspecified integral type, as does 8383 // C99 6.7.2.2p3. 8384 if (Enum->isFixed()) { 8385 EltTy = Enum->getIntegerType(); 8386 } 8387 else { 8388 EltTy = Context.IntTy; 8389 } 8390 } else { 8391 // Assign the last value + 1. 8392 EnumVal = LastEnumConst->getInitVal(); 8393 ++EnumVal; 8394 EltTy = LastEnumConst->getType(); 8395 8396 // Check for overflow on increment. 8397 if (EnumVal < LastEnumConst->getInitVal()) { 8398 // C++0x [dcl.enum]p5: 8399 // If the underlying type is not fixed, the type of each enumerator 8400 // is the type of its initializing value: 8401 // 8402 // - Otherwise the type of the initializing value is the same as 8403 // the type of the initializing value of the preceding enumerator 8404 // unless the incremented value is not representable in that type, 8405 // in which case the type is an unspecified integral type 8406 // sufficient to contain the incremented value. If no such type 8407 // exists, the program is ill-formed. 8408 QualType T = getNextLargerIntegralType(Context, EltTy); 8409 if (T.isNull() || Enum->isFixed()) { 8410 // There is no integral type larger enough to represent this 8411 // value. Complain, then allow the value to wrap around. 8412 EnumVal = LastEnumConst->getInitVal(); 8413 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 8414 ++EnumVal; 8415 if (Enum->isFixed()) 8416 // When the underlying type is fixed, this is ill-formed. 8417 Diag(IdLoc, diag::err_enumerator_wrapped) 8418 << EnumVal.toString(10) 8419 << EltTy; 8420 else 8421 Diag(IdLoc, diag::warn_enumerator_too_large) 8422 << EnumVal.toString(10); 8423 } else { 8424 EltTy = T; 8425 } 8426 8427 // Retrieve the last enumerator's value, extent that type to the 8428 // type that is supposed to be large enough to represent the incremented 8429 // value, then increment. 8430 EnumVal = LastEnumConst->getInitVal(); 8431 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType()); 8432 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 8433 ++EnumVal; 8434 8435 // If we're not in C++, diagnose the overflow of enumerator values, 8436 // which in C99 means that the enumerator value is not representable in 8437 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 8438 // permits enumerator values that are representable in some larger 8439 // integral type. 8440 if (!getLangOptions().CPlusPlus && !T.isNull()) 8441 Diag(IdLoc, diag::warn_enum_value_overflow); 8442 } else if (!getLangOptions().CPlusPlus && 8443 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 8444 // Enforce C99 6.7.2.2p2 even when we compute the next value. 8445 Diag(IdLoc, diag::ext_enum_value_not_int) 8446 << EnumVal.toString(10) << 1; 8447 } 8448 } 8449 } 8450 8451 if (!EltTy->isDependentType()) { 8452 // Make the enumerator value match the signedness and size of the 8453 // enumerator's type. 8454 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 8455 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType()); 8456 } 8457 8458 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 8459 Val, EnumVal); 8460} 8461 8462 8463Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 8464 SourceLocation IdLoc, IdentifierInfo *Id, 8465 AttributeList *Attr, 8466 SourceLocation EqualLoc, ExprTy *val) { 8467 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 8468 EnumConstantDecl *LastEnumConst = 8469 cast_or_null<EnumConstantDecl>(lastEnumConst); 8470 Expr *Val = static_cast<Expr*>(val); 8471 8472 // The scope passed in may not be a decl scope. Zip up the scope tree until 8473 // we find one that is. 8474 S = getNonFieldDeclScope(S); 8475 8476 // Verify that there isn't already something declared with this name in this 8477 // scope. 8478 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 8479 ForRedeclaration); 8480 if (PrevDecl && PrevDecl->isTemplateParameter()) { 8481 // Maybe we will complain about the shadowed template parameter. 8482 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 8483 // Just pretend that we didn't see the previous declaration. 8484 PrevDecl = 0; 8485 } 8486 8487 if (PrevDecl) { 8488 // When in C++, we may get a TagDecl with the same name; in this case the 8489 // enum constant will 'hide' the tag. 8490 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 8491 "Received TagDecl when not in C++!"); 8492 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 8493 if (isa<EnumConstantDecl>(PrevDecl)) 8494 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 8495 else 8496 Diag(IdLoc, diag::err_redefinition) << Id; 8497 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 8498 return 0; 8499 } 8500 } 8501 8502 // C++ [class.mem]p13: 8503 // If T is the name of a class, then each of the following shall have a 8504 // name different from T: 8505 // - every enumerator of every member of class T that is an enumerated 8506 // type 8507 if (CXXRecordDecl *Record 8508 = dyn_cast<CXXRecordDecl>( 8509 TheEnumDecl->getDeclContext()->getRedeclContext())) 8510 if (Record->getIdentifier() && Record->getIdentifier() == Id) 8511 Diag(IdLoc, diag::err_member_name_of_class) << Id; 8512 8513 EnumConstantDecl *New = 8514 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 8515 8516 if (New) { 8517 // Process attributes. 8518 if (Attr) ProcessDeclAttributeList(S, New, Attr); 8519 8520 // Register this decl in the current scope stack. 8521 New->setAccess(TheEnumDecl->getAccess()); 8522 PushOnScopeChains(New, S); 8523 } 8524 8525 return New; 8526} 8527 8528void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 8529 SourceLocation RBraceLoc, Decl *EnumDeclX, 8530 Decl **Elements, unsigned NumElements, 8531 Scope *S, AttributeList *Attr) { 8532 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 8533 QualType EnumType = Context.getTypeDeclType(Enum); 8534 8535 if (Attr) 8536 ProcessDeclAttributeList(S, Enum, Attr); 8537 8538 if (Enum->isDependentType()) { 8539 for (unsigned i = 0; i != NumElements; ++i) { 8540 EnumConstantDecl *ECD = 8541 cast_or_null<EnumConstantDecl>(Elements[i]); 8542 if (!ECD) continue; 8543 8544 ECD->setType(EnumType); 8545 } 8546 8547 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 8548 return; 8549 } 8550 8551 // TODO: If the result value doesn't fit in an int, it must be a long or long 8552 // long value. ISO C does not support this, but GCC does as an extension, 8553 // emit a warning. 8554 unsigned IntWidth = Context.Target.getIntWidth(); 8555 unsigned CharWidth = Context.Target.getCharWidth(); 8556 unsigned ShortWidth = Context.Target.getShortWidth(); 8557 8558 // Verify that all the values are okay, compute the size of the values, and 8559 // reverse the list. 8560 unsigned NumNegativeBits = 0; 8561 unsigned NumPositiveBits = 0; 8562 8563 // Keep track of whether all elements have type int. 8564 bool AllElementsInt = true; 8565 8566 for (unsigned i = 0; i != NumElements; ++i) { 8567 EnumConstantDecl *ECD = 8568 cast_or_null<EnumConstantDecl>(Elements[i]); 8569 if (!ECD) continue; // Already issued a diagnostic. 8570 8571 const llvm::APSInt &InitVal = ECD->getInitVal(); 8572 8573 // Keep track of the size of positive and negative values. 8574 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 8575 NumPositiveBits = std::max(NumPositiveBits, 8576 (unsigned)InitVal.getActiveBits()); 8577 else 8578 NumNegativeBits = std::max(NumNegativeBits, 8579 (unsigned)InitVal.getMinSignedBits()); 8580 8581 // Keep track of whether every enum element has type int (very commmon). 8582 if (AllElementsInt) 8583 AllElementsInt = ECD->getType() == Context.IntTy; 8584 } 8585 8586 // Figure out the type that should be used for this enum. 8587 QualType BestType; 8588 unsigned BestWidth; 8589 8590 // C++0x N3000 [conv.prom]p3: 8591 // An rvalue of an unscoped enumeration type whose underlying 8592 // type is not fixed can be converted to an rvalue of the first 8593 // of the following types that can represent all the values of 8594 // the enumeration: int, unsigned int, long int, unsigned long 8595 // int, long long int, or unsigned long long int. 8596 // C99 6.4.4.3p2: 8597 // An identifier declared as an enumeration constant has type int. 8598 // The C99 rule is modified by a gcc extension 8599 QualType BestPromotionType; 8600 8601 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 8602 // -fshort-enums is the equivalent to specifying the packed attribute on all 8603 // enum definitions. 8604 if (LangOpts.ShortEnums) 8605 Packed = true; 8606 8607 if (Enum->isFixed()) { 8608 BestType = BestPromotionType = Enum->getIntegerType(); 8609 // We don't need to set BestWidth, because BestType is going to be the type 8610 // of the enumerators, but we do anyway because otherwise some compilers 8611 // warn that it might be used uninitialized. 8612 BestWidth = CharWidth; 8613 } 8614 else if (NumNegativeBits) { 8615 // If there is a negative value, figure out the smallest integer type (of 8616 // int/long/longlong) that fits. 8617 // If it's packed, check also if it fits a char or a short. 8618 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 8619 BestType = Context.SignedCharTy; 8620 BestWidth = CharWidth; 8621 } else if (Packed && NumNegativeBits <= ShortWidth && 8622 NumPositiveBits < ShortWidth) { 8623 BestType = Context.ShortTy; 8624 BestWidth = ShortWidth; 8625 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 8626 BestType = Context.IntTy; 8627 BestWidth = IntWidth; 8628 } else { 8629 BestWidth = Context.Target.getLongWidth(); 8630 8631 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 8632 BestType = Context.LongTy; 8633 } else { 8634 BestWidth = Context.Target.getLongLongWidth(); 8635 8636 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 8637 Diag(Enum->getLocation(), diag::warn_enum_too_large); 8638 BestType = Context.LongLongTy; 8639 } 8640 } 8641 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 8642 } else { 8643 // If there is no negative value, figure out the smallest type that fits 8644 // all of the enumerator values. 8645 // If it's packed, check also if it fits a char or a short. 8646 if (Packed && NumPositiveBits <= CharWidth) { 8647 BestType = Context.UnsignedCharTy; 8648 BestPromotionType = Context.IntTy; 8649 BestWidth = CharWidth; 8650 } else if (Packed && NumPositiveBits <= ShortWidth) { 8651 BestType = Context.UnsignedShortTy; 8652 BestPromotionType = Context.IntTy; 8653 BestWidth = ShortWidth; 8654 } else if (NumPositiveBits <= IntWidth) { 8655 BestType = Context.UnsignedIntTy; 8656 BestWidth = IntWidth; 8657 BestPromotionType 8658 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8659 ? Context.UnsignedIntTy : Context.IntTy; 8660 } else if (NumPositiveBits <= 8661 (BestWidth = Context.Target.getLongWidth())) { 8662 BestType = Context.UnsignedLongTy; 8663 BestPromotionType 8664 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8665 ? Context.UnsignedLongTy : Context.LongTy; 8666 } else { 8667 BestWidth = Context.Target.getLongLongWidth(); 8668 assert(NumPositiveBits <= BestWidth && 8669 "How could an initializer get larger than ULL?"); 8670 BestType = Context.UnsignedLongLongTy; 8671 BestPromotionType 8672 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8673 ? Context.UnsignedLongLongTy : Context.LongLongTy; 8674 } 8675 } 8676 8677 // Loop over all of the enumerator constants, changing their types to match 8678 // the type of the enum if needed. 8679 for (unsigned i = 0; i != NumElements; ++i) { 8680 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 8681 if (!ECD) continue; // Already issued a diagnostic. 8682 8683 // Standard C says the enumerators have int type, but we allow, as an 8684 // extension, the enumerators to be larger than int size. If each 8685 // enumerator value fits in an int, type it as an int, otherwise type it the 8686 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 8687 // that X has type 'int', not 'unsigned'. 8688 8689 // Determine whether the value fits into an int. 8690 llvm::APSInt InitVal = ECD->getInitVal(); 8691 8692 // If it fits into an integer type, force it. Otherwise force it to match 8693 // the enum decl type. 8694 QualType NewTy; 8695 unsigned NewWidth; 8696 bool NewSign; 8697 if (!getLangOptions().CPlusPlus && 8698 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 8699 NewTy = Context.IntTy; 8700 NewWidth = IntWidth; 8701 NewSign = true; 8702 } else if (ECD->getType() == BestType) { 8703 // Already the right type! 8704 if (getLangOptions().CPlusPlus) 8705 // C++ [dcl.enum]p4: Following the closing brace of an 8706 // enum-specifier, each enumerator has the type of its 8707 // enumeration. 8708 ECD->setType(EnumType); 8709 continue; 8710 } else { 8711 NewTy = BestType; 8712 NewWidth = BestWidth; 8713 NewSign = BestType->isSignedIntegerOrEnumerationType(); 8714 } 8715 8716 // Adjust the APSInt value. 8717 InitVal = InitVal.extOrTrunc(NewWidth); 8718 InitVal.setIsSigned(NewSign); 8719 ECD->setInitVal(InitVal); 8720 8721 // Adjust the Expr initializer and type. 8722 if (ECD->getInitExpr() && 8723 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 8724 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 8725 CK_IntegralCast, 8726 ECD->getInitExpr(), 8727 /*base paths*/ 0, 8728 VK_RValue)); 8729 if (getLangOptions().CPlusPlus) 8730 // C++ [dcl.enum]p4: Following the closing brace of an 8731 // enum-specifier, each enumerator has the type of its 8732 // enumeration. 8733 ECD->setType(EnumType); 8734 else 8735 ECD->setType(NewTy); 8736 } 8737 8738 Enum->completeDefinition(BestType, BestPromotionType, 8739 NumPositiveBits, NumNegativeBits); 8740} 8741 8742Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 8743 SourceLocation StartLoc, 8744 SourceLocation EndLoc) { 8745 StringLiteral *AsmString = cast<StringLiteral>(expr); 8746 8747 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 8748 AsmString, StartLoc, 8749 EndLoc); 8750 CurContext->addDecl(New); 8751 return New; 8752} 8753 8754void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 8755 SourceLocation PragmaLoc, 8756 SourceLocation NameLoc) { 8757 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 8758 8759 if (PrevDecl) { 8760 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 8761 } else { 8762 (void)WeakUndeclaredIdentifiers.insert( 8763 std::pair<IdentifierInfo*,WeakInfo> 8764 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 8765 } 8766} 8767 8768void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 8769 IdentifierInfo* AliasName, 8770 SourceLocation PragmaLoc, 8771 SourceLocation NameLoc, 8772 SourceLocation AliasNameLoc) { 8773 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 8774 LookupOrdinaryName); 8775 WeakInfo W = WeakInfo(Name, NameLoc); 8776 8777 if (PrevDecl) { 8778 if (!PrevDecl->hasAttr<AliasAttr>()) 8779 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 8780 DeclApplyPragmaWeak(TUScope, ND, W); 8781 } else { 8782 (void)WeakUndeclaredIdentifiers.insert( 8783 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 8784 } 8785} 8786