SemaDecl.cpp revision 3215398dc9dac2be19a9fc1df929e6b7d83eafca
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->isDefaultConstructor()) 1509 return Sema::CXXDefaultConstructor; 1510 1511 if (Ctor->isCopyConstructor()) 1512 return Sema::CXXCopyConstructor; 1513 1514 if (Ctor->isMoveConstructor()) 1515 return Sema::CXXMoveConstructor; 1516 } else if (isa<CXXDestructorDecl>(MD)) { 1517 return Sema::CXXDestructor; 1518 } else if (MD->isCopyAssignmentOperator()) { 1519 return Sema::CXXCopyAssignment; 1520 } 1521 1522 return Sema::CXXInvalid; 1523} 1524 1525/// canRedefineFunction - checks if a function can be redefined. Currently, 1526/// only extern inline functions can be redefined, and even then only in 1527/// GNU89 mode. 1528static bool canRedefineFunction(const FunctionDecl *FD, 1529 const LangOptions& LangOpts) { 1530 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) && 1531 !LangOpts.CPlusPlus && 1532 FD->isInlineSpecified() && 1533 FD->getStorageClass() == SC_Extern); 1534} 1535 1536/// MergeFunctionDecl - We just parsed a function 'New' from 1537/// declarator D which has the same name and scope as a previous 1538/// declaration 'Old'. Figure out how to resolve this situation, 1539/// merging decls or emitting diagnostics as appropriate. 1540/// 1541/// In C++, New and Old must be declarations that are not 1542/// overloaded. Use IsOverload to determine whether New and Old are 1543/// overloaded, and to select the Old declaration that New should be 1544/// merged with. 1545/// 1546/// Returns true if there was an error, false otherwise. 1547bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1548 // Verify the old decl was also a function. 1549 FunctionDecl *Old = 0; 1550 if (FunctionTemplateDecl *OldFunctionTemplate 1551 = dyn_cast<FunctionTemplateDecl>(OldD)) 1552 Old = OldFunctionTemplate->getTemplatedDecl(); 1553 else 1554 Old = dyn_cast<FunctionDecl>(OldD); 1555 if (!Old) { 1556 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1557 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1558 Diag(Shadow->getTargetDecl()->getLocation(), 1559 diag::note_using_decl_target); 1560 Diag(Shadow->getUsingDecl()->getLocation(), 1561 diag::note_using_decl) << 0; 1562 return true; 1563 } 1564 1565 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1566 << New->getDeclName(); 1567 Diag(OldD->getLocation(), diag::note_previous_definition); 1568 return true; 1569 } 1570 1571 // Determine whether the previous declaration was a definition, 1572 // implicit declaration, or a declaration. 1573 diag::kind PrevDiag; 1574 if (Old->isThisDeclarationADefinition()) 1575 PrevDiag = diag::note_previous_definition; 1576 else if (Old->isImplicit()) 1577 PrevDiag = diag::note_previous_implicit_declaration; 1578 else 1579 PrevDiag = diag::note_previous_declaration; 1580 1581 QualType OldQType = Context.getCanonicalType(Old->getType()); 1582 QualType NewQType = Context.getCanonicalType(New->getType()); 1583 1584 // Don't complain about this if we're in GNU89 mode and the old function 1585 // is an extern inline function. 1586 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1587 New->getStorageClass() == SC_Static && 1588 Old->getStorageClass() != SC_Static && 1589 !canRedefineFunction(Old, getLangOptions())) { 1590 if (getLangOptions().Microsoft) { 1591 Diag(New->getLocation(), diag::warn_static_non_static) << New; 1592 Diag(Old->getLocation(), PrevDiag); 1593 } else { 1594 Diag(New->getLocation(), diag::err_static_non_static) << New; 1595 Diag(Old->getLocation(), PrevDiag); 1596 return true; 1597 } 1598 } 1599 1600 // If a function is first declared with a calling convention, but is 1601 // later declared or defined without one, the second decl assumes the 1602 // calling convention of the first. 1603 // 1604 // For the new decl, we have to look at the NON-canonical type to tell the 1605 // difference between a function that really doesn't have a calling 1606 // convention and one that is declared cdecl. That's because in 1607 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1608 // because it is the default calling convention. 1609 // 1610 // Note also that we DO NOT return at this point, because we still have 1611 // other tests to run. 1612 const FunctionType *OldType = cast<FunctionType>(OldQType); 1613 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1614 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1615 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1616 bool RequiresAdjustment = false; 1617 if (OldTypeInfo.getCC() != CC_Default && 1618 NewTypeInfo.getCC() == CC_Default) { 1619 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1620 RequiresAdjustment = true; 1621 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1622 NewTypeInfo.getCC())) { 1623 // Calling conventions really aren't compatible, so complain. 1624 Diag(New->getLocation(), diag::err_cconv_change) 1625 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1626 << (OldTypeInfo.getCC() == CC_Default) 1627 << (OldTypeInfo.getCC() == CC_Default ? "" : 1628 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1629 Diag(Old->getLocation(), diag::note_previous_declaration); 1630 return true; 1631 } 1632 1633 // FIXME: diagnose the other way around? 1634 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1635 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1636 RequiresAdjustment = true; 1637 } 1638 1639 // Merge regparm attribute. 1640 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || 1641 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1642 if (NewTypeInfo.getHasRegParm()) { 1643 Diag(New->getLocation(), diag::err_regparm_mismatch) 1644 << NewType->getRegParmType() 1645 << OldType->getRegParmType(); 1646 Diag(Old->getLocation(), diag::note_previous_declaration); 1647 return true; 1648 } 1649 1650 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1651 RequiresAdjustment = true; 1652 } 1653 1654 if (RequiresAdjustment) { 1655 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1656 New->setType(QualType(NewType, 0)); 1657 NewQType = Context.getCanonicalType(New->getType()); 1658 } 1659 1660 if (getLangOptions().CPlusPlus) { 1661 // (C++98 13.1p2): 1662 // Certain function declarations cannot be overloaded: 1663 // -- Function declarations that differ only in the return type 1664 // cannot be overloaded. 1665 QualType OldReturnType = OldType->getResultType(); 1666 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1667 QualType ResQT; 1668 if (OldReturnType != NewReturnType) { 1669 if (NewReturnType->isObjCObjectPointerType() 1670 && OldReturnType->isObjCObjectPointerType()) 1671 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1672 if (ResQT.isNull()) { 1673 if (New->isCXXClassMember() && New->isOutOfLine()) 1674 Diag(New->getLocation(), 1675 diag::err_member_def_does_not_match_ret_type) << New; 1676 else 1677 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1678 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1679 return true; 1680 } 1681 else 1682 NewQType = ResQT; 1683 } 1684 1685 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1686 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1687 if (OldMethod && NewMethod) { 1688 // Preserve triviality. 1689 NewMethod->setTrivial(OldMethod->isTrivial()); 1690 1691 bool isFriend = NewMethod->getFriendObjectKind(); 1692 1693 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1694 // -- Member function declarations with the same name and the 1695 // same parameter types cannot be overloaded if any of them 1696 // is a static member function declaration. 1697 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1698 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1699 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1700 return true; 1701 } 1702 1703 // C++ [class.mem]p1: 1704 // [...] A member shall not be declared twice in the 1705 // member-specification, except that a nested class or member 1706 // class template can be declared and then later defined. 1707 unsigned NewDiag; 1708 if (isa<CXXConstructorDecl>(OldMethod)) 1709 NewDiag = diag::err_constructor_redeclared; 1710 else if (isa<CXXDestructorDecl>(NewMethod)) 1711 NewDiag = diag::err_destructor_redeclared; 1712 else if (isa<CXXConversionDecl>(NewMethod)) 1713 NewDiag = diag::err_conv_function_redeclared; 1714 else 1715 NewDiag = diag::err_member_redeclared; 1716 1717 Diag(New->getLocation(), NewDiag); 1718 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1719 1720 // Complain if this is an explicit declaration of a special 1721 // member that was initially declared implicitly. 1722 // 1723 // As an exception, it's okay to befriend such methods in order 1724 // to permit the implicit constructor/destructor/operator calls. 1725 } else if (OldMethod->isImplicit()) { 1726 if (isFriend) { 1727 NewMethod->setImplicit(); 1728 } else { 1729 Diag(NewMethod->getLocation(), 1730 diag::err_definition_of_implicitly_declared_member) 1731 << New << getSpecialMember(OldMethod); 1732 return true; 1733 } 1734 } else if (OldMethod->isExplicitlyDefaulted()) { 1735 Diag(NewMethod->getLocation(), 1736 diag::err_definition_of_explicitly_defaulted_member) 1737 << getSpecialMember(OldMethod); 1738 return true; 1739 } 1740 } 1741 1742 // (C++98 8.3.5p3): 1743 // All declarations for a function shall agree exactly in both the 1744 // return type and the parameter-type-list. 1745 // We also want to respect all the extended bits except noreturn. 1746 1747 // noreturn should now match unless the old type info didn't have it. 1748 QualType OldQTypeForComparison = OldQType; 1749 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1750 assert(OldQType == QualType(OldType, 0)); 1751 const FunctionType *OldTypeForComparison 1752 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1753 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1754 assert(OldQTypeForComparison.isCanonical()); 1755 } 1756 1757 if (OldQTypeForComparison == NewQType) 1758 return MergeCompatibleFunctionDecls(New, Old); 1759 1760 // Fall through for conflicting redeclarations and redefinitions. 1761 } 1762 1763 // C: Function types need to be compatible, not identical. This handles 1764 // duplicate function decls like "void f(int); void f(enum X);" properly. 1765 if (!getLangOptions().CPlusPlus && 1766 Context.typesAreCompatible(OldQType, NewQType)) { 1767 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1768 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1769 const FunctionProtoType *OldProto = 0; 1770 if (isa<FunctionNoProtoType>(NewFuncType) && 1771 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1772 // The old declaration provided a function prototype, but the 1773 // new declaration does not. Merge in the prototype. 1774 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1775 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1776 OldProto->arg_type_end()); 1777 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1778 ParamTypes.data(), ParamTypes.size(), 1779 OldProto->getExtProtoInfo()); 1780 New->setType(NewQType); 1781 New->setHasInheritedPrototype(); 1782 1783 // Synthesize a parameter for each argument type. 1784 llvm::SmallVector<ParmVarDecl*, 16> Params; 1785 for (FunctionProtoType::arg_type_iterator 1786 ParamType = OldProto->arg_type_begin(), 1787 ParamEnd = OldProto->arg_type_end(); 1788 ParamType != ParamEnd; ++ParamType) { 1789 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1790 SourceLocation(), 1791 SourceLocation(), 0, 1792 *ParamType, /*TInfo=*/0, 1793 SC_None, SC_None, 1794 0); 1795 Param->setScopeInfo(0, Params.size()); 1796 Param->setImplicit(); 1797 Params.push_back(Param); 1798 } 1799 1800 New->setParams(Params.data(), Params.size()); 1801 } 1802 1803 return MergeCompatibleFunctionDecls(New, Old); 1804 } 1805 1806 // GNU C permits a K&R definition to follow a prototype declaration 1807 // if the declared types of the parameters in the K&R definition 1808 // match the types in the prototype declaration, even when the 1809 // promoted types of the parameters from the K&R definition differ 1810 // from the types in the prototype. GCC then keeps the types from 1811 // the prototype. 1812 // 1813 // If a variadic prototype is followed by a non-variadic K&R definition, 1814 // the K&R definition becomes variadic. This is sort of an edge case, but 1815 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1816 // C99 6.9.1p8. 1817 if (!getLangOptions().CPlusPlus && 1818 Old->hasPrototype() && !New->hasPrototype() && 1819 New->getType()->getAs<FunctionProtoType>() && 1820 Old->getNumParams() == New->getNumParams()) { 1821 llvm::SmallVector<QualType, 16> ArgTypes; 1822 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1823 const FunctionProtoType *OldProto 1824 = Old->getType()->getAs<FunctionProtoType>(); 1825 const FunctionProtoType *NewProto 1826 = New->getType()->getAs<FunctionProtoType>(); 1827 1828 // Determine whether this is the GNU C extension. 1829 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1830 NewProto->getResultType()); 1831 bool LooseCompatible = !MergedReturn.isNull(); 1832 for (unsigned Idx = 0, End = Old->getNumParams(); 1833 LooseCompatible && Idx != End; ++Idx) { 1834 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1835 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1836 if (Context.typesAreCompatible(OldParm->getType(), 1837 NewProto->getArgType(Idx))) { 1838 ArgTypes.push_back(NewParm->getType()); 1839 } else if (Context.typesAreCompatible(OldParm->getType(), 1840 NewParm->getType(), 1841 /*CompareUnqualified=*/true)) { 1842 GNUCompatibleParamWarning Warn 1843 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1844 Warnings.push_back(Warn); 1845 ArgTypes.push_back(NewParm->getType()); 1846 } else 1847 LooseCompatible = false; 1848 } 1849 1850 if (LooseCompatible) { 1851 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1852 Diag(Warnings[Warn].NewParm->getLocation(), 1853 diag::ext_param_promoted_not_compatible_with_prototype) 1854 << Warnings[Warn].PromotedType 1855 << Warnings[Warn].OldParm->getType(); 1856 if (Warnings[Warn].OldParm->getLocation().isValid()) 1857 Diag(Warnings[Warn].OldParm->getLocation(), 1858 diag::note_previous_declaration); 1859 } 1860 1861 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1862 ArgTypes.size(), 1863 OldProto->getExtProtoInfo())); 1864 return MergeCompatibleFunctionDecls(New, Old); 1865 } 1866 1867 // Fall through to diagnose conflicting types. 1868 } 1869 1870 // A function that has already been declared has been redeclared or defined 1871 // with a different type- show appropriate diagnostic 1872 if (unsigned BuiltinID = Old->getBuiltinID()) { 1873 // The user has declared a builtin function with an incompatible 1874 // signature. 1875 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1876 // The function the user is redeclaring is a library-defined 1877 // function like 'malloc' or 'printf'. Warn about the 1878 // redeclaration, then pretend that we don't know about this 1879 // library built-in. 1880 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1881 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1882 << Old << Old->getType(); 1883 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1884 Old->setInvalidDecl(); 1885 return false; 1886 } 1887 1888 PrevDiag = diag::note_previous_builtin_declaration; 1889 } 1890 1891 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1892 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1893 return true; 1894} 1895 1896/// \brief Completes the merge of two function declarations that are 1897/// known to be compatible. 1898/// 1899/// This routine handles the merging of attributes and other 1900/// properties of function declarations form the old declaration to 1901/// the new declaration, once we know that New is in fact a 1902/// redeclaration of Old. 1903/// 1904/// \returns false 1905bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1906 // Merge the attributes 1907 mergeDeclAttributes(New, Old, Context); 1908 1909 // Merge the storage class. 1910 if (Old->getStorageClass() != SC_Extern && 1911 Old->getStorageClass() != SC_None) 1912 New->setStorageClass(Old->getStorageClass()); 1913 1914 // Merge "pure" flag. 1915 if (Old->isPure()) 1916 New->setPure(); 1917 1918 // Merge attributes from the parameters. These can mismatch with K&R 1919 // declarations. 1920 if (New->getNumParams() == Old->getNumParams()) 1921 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1922 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1923 Context); 1924 1925 if (getLangOptions().CPlusPlus) 1926 return MergeCXXFunctionDecl(New, Old); 1927 1928 return false; 1929} 1930 1931 1932void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1933 const ObjCMethodDecl *oldMethod) { 1934 // Merge the attributes. 1935 mergeDeclAttributes(newMethod, oldMethod, Context); 1936 1937 // Merge attributes from the parameters. 1938 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1939 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1940 ni != ne; ++ni, ++oi) 1941 mergeParamDeclAttributes(*ni, *oi, Context); 1942 1943 CheckObjCMethodOverride(newMethod, oldMethod, true); 1944} 1945 1946/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 1947/// scope as a previous declaration 'Old'. Figure out how to merge their types, 1948/// emitting diagnostics as appropriate. 1949/// 1950/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1951/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1952/// check them before the initializer is attached. 1953/// 1954void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1955 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1956 return; 1957 1958 QualType MergedT; 1959 if (getLangOptions().CPlusPlus) { 1960 AutoType *AT = New->getType()->getContainedAutoType(); 1961 if (AT && !AT->isDeduced()) { 1962 // We don't know what the new type is until the initializer is attached. 1963 return; 1964 } else if (Context.hasSameType(New->getType(), Old->getType())) { 1965 // These could still be something that needs exception specs checked. 1966 return MergeVarDeclExceptionSpecs(New, Old); 1967 } 1968 // C++ [basic.link]p10: 1969 // [...] the types specified by all declarations referring to a given 1970 // object or function shall be identical, except that declarations for an 1971 // array object can specify array types that differ by the presence or 1972 // absence of a major array bound (8.3.4). 1973 else if (Old->getType()->isIncompleteArrayType() && 1974 New->getType()->isArrayType()) { 1975 CanQual<ArrayType> OldArray 1976 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1977 CanQual<ArrayType> NewArray 1978 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1979 if (OldArray->getElementType() == NewArray->getElementType()) 1980 MergedT = New->getType(); 1981 } else if (Old->getType()->isArrayType() && 1982 New->getType()->isIncompleteArrayType()) { 1983 CanQual<ArrayType> OldArray 1984 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1985 CanQual<ArrayType> NewArray 1986 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1987 if (OldArray->getElementType() == NewArray->getElementType()) 1988 MergedT = Old->getType(); 1989 } else if (New->getType()->isObjCObjectPointerType() 1990 && Old->getType()->isObjCObjectPointerType()) { 1991 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1992 Old->getType()); 1993 } 1994 } else { 1995 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1996 } 1997 if (MergedT.isNull()) { 1998 Diag(New->getLocation(), diag::err_redefinition_different_type) 1999 << New->getDeclName(); 2000 Diag(Old->getLocation(), diag::note_previous_definition); 2001 return New->setInvalidDecl(); 2002 } 2003 New->setType(MergedT); 2004} 2005 2006/// MergeVarDecl - We just parsed a variable 'New' which has the same name 2007/// and scope as a previous declaration 'Old'. Figure out how to resolve this 2008/// situation, merging decls or emitting diagnostics as appropriate. 2009/// 2010/// Tentative definition rules (C99 6.9.2p2) are checked by 2011/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 2012/// definitions here, since the initializer hasn't been attached. 2013/// 2014void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 2015 // If the new decl is already invalid, don't do any other checking. 2016 if (New->isInvalidDecl()) 2017 return; 2018 2019 // Verify the old decl was also a variable. 2020 VarDecl *Old = 0; 2021 if (!Previous.isSingleResult() || 2022 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 2023 Diag(New->getLocation(), diag::err_redefinition_different_kind) 2024 << New->getDeclName(); 2025 Diag(Previous.getRepresentativeDecl()->getLocation(), 2026 diag::note_previous_definition); 2027 return New->setInvalidDecl(); 2028 } 2029 2030 // C++ [class.mem]p1: 2031 // A member shall not be declared twice in the member-specification [...] 2032 // 2033 // Here, we need only consider static data members. 2034 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 2035 Diag(New->getLocation(), diag::err_duplicate_member) 2036 << New->getIdentifier(); 2037 Diag(Old->getLocation(), diag::note_previous_declaration); 2038 New->setInvalidDecl(); 2039 } 2040 2041 mergeDeclAttributes(New, Old, Context); 2042 // Warn if an already-declared variable is made a weak_import in a subsequent declaration 2043 if (New->getAttr<WeakImportAttr>() && 2044 Old->getStorageClass() == SC_None && 2045 !Old->getAttr<WeakImportAttr>()) { 2046 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName(); 2047 Diag(Old->getLocation(), diag::note_previous_definition); 2048 // Remove weak_import attribute on new declaration. 2049 New->dropAttr<WeakImportAttr>(); 2050 } 2051 2052 // Merge the types. 2053 MergeVarDeclTypes(New, Old); 2054 if (New->isInvalidDecl()) 2055 return; 2056 2057 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 2058 if (New->getStorageClass() == SC_Static && 2059 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 2060 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 2061 Diag(Old->getLocation(), diag::note_previous_definition); 2062 return New->setInvalidDecl(); 2063 } 2064 // C99 6.2.2p4: 2065 // For an identifier declared with the storage-class specifier 2066 // extern in a scope in which a prior declaration of that 2067 // identifier is visible,23) if the prior declaration specifies 2068 // internal or external linkage, the linkage of the identifier at 2069 // the later declaration is the same as the linkage specified at 2070 // the prior declaration. If no prior declaration is visible, or 2071 // if the prior declaration specifies no linkage, then the 2072 // identifier has external linkage. 2073 if (New->hasExternalStorage() && Old->hasLinkage()) 2074 /* Okay */; 2075 else if (New->getStorageClass() != SC_Static && 2076 Old->getStorageClass() == SC_Static) { 2077 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 2078 Diag(Old->getLocation(), diag::note_previous_definition); 2079 return New->setInvalidDecl(); 2080 } 2081 2082 // Check if extern is followed by non-extern and vice-versa. 2083 if (New->hasExternalStorage() && 2084 !Old->hasLinkage() && Old->isLocalVarDecl()) { 2085 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 2086 Diag(Old->getLocation(), diag::note_previous_definition); 2087 return New->setInvalidDecl(); 2088 } 2089 if (Old->hasExternalStorage() && 2090 !New->hasLinkage() && New->isLocalVarDecl()) { 2091 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 2092 Diag(Old->getLocation(), diag::note_previous_definition); 2093 return New->setInvalidDecl(); 2094 } 2095 2096 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 2097 2098 // FIXME: The test for external storage here seems wrong? We still 2099 // need to check for mismatches. 2100 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 2101 // Don't complain about out-of-line definitions of static members. 2102 !(Old->getLexicalDeclContext()->isRecord() && 2103 !New->getLexicalDeclContext()->isRecord())) { 2104 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 2105 Diag(Old->getLocation(), diag::note_previous_definition); 2106 return New->setInvalidDecl(); 2107 } 2108 2109 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 2110 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 2111 Diag(Old->getLocation(), diag::note_previous_definition); 2112 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 2113 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 2114 Diag(Old->getLocation(), diag::note_previous_definition); 2115 } 2116 2117 // C++ doesn't have tentative definitions, so go right ahead and check here. 2118 const VarDecl *Def; 2119 if (getLangOptions().CPlusPlus && 2120 New->isThisDeclarationADefinition() == VarDecl::Definition && 2121 (Def = Old->getDefinition())) { 2122 Diag(New->getLocation(), diag::err_redefinition) 2123 << New->getDeclName(); 2124 Diag(Def->getLocation(), diag::note_previous_definition); 2125 New->setInvalidDecl(); 2126 return; 2127 } 2128 // c99 6.2.2 P4. 2129 // For an identifier declared with the storage-class specifier extern in a 2130 // scope in which a prior declaration of that identifier is visible, if 2131 // the prior declaration specifies internal or external linkage, the linkage 2132 // of the identifier at the later declaration is the same as the linkage 2133 // specified at the prior declaration. 2134 // FIXME. revisit this code. 2135 if (New->hasExternalStorage() && 2136 Old->getLinkage() == InternalLinkage && 2137 New->getDeclContext() == Old->getDeclContext()) 2138 New->setStorageClass(Old->getStorageClass()); 2139 2140 // Keep a chain of previous declarations. 2141 New->setPreviousDeclaration(Old); 2142 2143 // Inherit access appropriately. 2144 New->setAccess(Old->getAccess()); 2145} 2146 2147/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 2148/// no declarator (e.g. "struct foo;") is parsed. 2149Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 2150 DeclSpec &DS) { 2151 return ParsedFreeStandingDeclSpec(S, AS, DS, 2152 MultiTemplateParamsArg(*this, 0, 0)); 2153} 2154 2155/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 2156/// no declarator (e.g. "struct foo;") is parsed. It also accopts template 2157/// parameters to cope with template friend declarations. 2158Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 2159 DeclSpec &DS, 2160 MultiTemplateParamsArg TemplateParams) { 2161 Decl *TagD = 0; 2162 TagDecl *Tag = 0; 2163 if (DS.getTypeSpecType() == DeclSpec::TST_class || 2164 DS.getTypeSpecType() == DeclSpec::TST_struct || 2165 DS.getTypeSpecType() == DeclSpec::TST_union || 2166 DS.getTypeSpecType() == DeclSpec::TST_enum) { 2167 TagD = DS.getRepAsDecl(); 2168 2169 if (!TagD) // We probably had an error 2170 return 0; 2171 2172 // Note that the above type specs guarantee that the 2173 // type rep is a Decl, whereas in many of the others 2174 // it's a Type. 2175 Tag = dyn_cast<TagDecl>(TagD); 2176 } 2177 2178 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 2179 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 2180 // or incomplete types shall not be restrict-qualified." 2181 if (TypeQuals & DeclSpec::TQ_restrict) 2182 Diag(DS.getRestrictSpecLoc(), 2183 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 2184 << DS.getSourceRange(); 2185 } 2186 2187 if (DS.isFriendSpecified()) { 2188 // If we're dealing with a decl but not a TagDecl, assume that 2189 // whatever routines created it handled the friendship aspect. 2190 if (TagD && !Tag) 2191 return 0; 2192 return ActOnFriendTypeDecl(S, DS, TemplateParams); 2193 } 2194 2195 // Track whether we warned about the fact that there aren't any 2196 // declarators. 2197 bool emittedWarning = false; 2198 2199 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 2200 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 2201 2202 if (!Record->getDeclName() && Record->isDefinition() && 2203 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 2204 if (getLangOptions().CPlusPlus || 2205 Record->getDeclContext()->isRecord()) 2206 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 2207 2208 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 2209 << DS.getSourceRange(); 2210 emittedWarning = true; 2211 } 2212 } 2213 2214 // Check for Microsoft C extension: anonymous struct. 2215 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 2216 CurContext->isRecord() && 2217 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 2218 // Handle 2 kinds of anonymous struct: 2219 // struct STRUCT; 2220 // and 2221 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 2222 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 2223 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 2224 (DS.getTypeSpecType() == DeclSpec::TST_typename && 2225 DS.getRepAsType().get()->isStructureType())) { 2226 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 2227 << DS.getSourceRange(); 2228 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 2229 } 2230 } 2231 2232 if (getLangOptions().CPlusPlus && 2233 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 2234 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 2235 if (Enum->enumerator_begin() == Enum->enumerator_end() && 2236 !Enum->getIdentifier() && !Enum->isInvalidDecl()) { 2237 Diag(Enum->getLocation(), diag::ext_no_declarators) 2238 << DS.getSourceRange(); 2239 emittedWarning = true; 2240 } 2241 2242 // Skip all the checks below if we have a type error. 2243 if (DS.getTypeSpecType() == DeclSpec::TST_error) return TagD; 2244 2245 if (!DS.isMissingDeclaratorOk()) { 2246 // Warn about typedefs of enums without names, since this is an 2247 // extension in both Microsoft and GNU. 2248 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 2249 Tag && isa<EnumDecl>(Tag)) { 2250 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 2251 << DS.getSourceRange(); 2252 return Tag; 2253 } 2254 2255 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 2256 << DS.getSourceRange(); 2257 emittedWarning = true; 2258 } 2259 2260 // We're going to complain about a bunch of spurious specifiers; 2261 // only do this if we're declaring a tag, because otherwise we 2262 // should be getting diag::ext_no_declarators. 2263 if (emittedWarning || (TagD && TagD->isInvalidDecl())) 2264 return TagD; 2265 2266 // Note that a linkage-specification sets a storage class, but 2267 // 'extern "C" struct foo;' is actually valid and not theoretically 2268 // useless. 2269 if (DeclSpec::SCS scs = DS.getStorageClassSpec()) 2270 if (!DS.isExternInLinkageSpec()) 2271 Diag(DS.getStorageClassSpecLoc(), diag::warn_standalone_specifier) 2272 << DeclSpec::getSpecifierName(scs); 2273 2274 if (DS.isThreadSpecified()) 2275 Diag(DS.getThreadSpecLoc(), diag::warn_standalone_specifier) << "__thread"; 2276 if (DS.getTypeQualifiers()) { 2277 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 2278 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "const"; 2279 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 2280 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "volatile"; 2281 // Restrict is covered above. 2282 } 2283 if (DS.isInlineSpecified()) 2284 Diag(DS.getInlineSpecLoc(), diag::warn_standalone_specifier) << "inline"; 2285 if (DS.isVirtualSpecified()) 2286 Diag(DS.getVirtualSpecLoc(), diag::warn_standalone_specifier) << "virtual"; 2287 if (DS.isExplicitSpecified()) 2288 Diag(DS.getExplicitSpecLoc(), diag::warn_standalone_specifier) <<"explicit"; 2289 2290 // FIXME: Warn on useless attributes 2291 2292 return TagD; 2293} 2294 2295/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 2296/// builds a statement for it and returns it so it is evaluated. 2297StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 2298 StmtResult R; 2299 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 2300 Expr *Exp = DS.getRepAsExpr(); 2301 QualType Ty = Exp->getType(); 2302 if (Ty->isPointerType()) { 2303 do 2304 Ty = Ty->getAs<PointerType>()->getPointeeType(); 2305 while (Ty->isPointerType()); 2306 } 2307 if (Ty->isVariableArrayType()) { 2308 R = ActOnExprStmt(MakeFullExpr(Exp)); 2309 } 2310 } 2311 return R; 2312} 2313 2314/// We are trying to inject an anonymous member into the given scope; 2315/// check if there's an existing declaration that can't be overloaded. 2316/// 2317/// \return true if this is a forbidden redeclaration 2318static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 2319 Scope *S, 2320 DeclContext *Owner, 2321 DeclarationName Name, 2322 SourceLocation NameLoc, 2323 unsigned diagnostic) { 2324 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 2325 Sema::ForRedeclaration); 2326 if (!SemaRef.LookupName(R, S)) return false; 2327 2328 if (R.getAsSingle<TagDecl>()) 2329 return false; 2330 2331 // Pick a representative declaration. 2332 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 2333 assert(PrevDecl && "Expected a non-null Decl"); 2334 2335 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 2336 return false; 2337 2338 SemaRef.Diag(NameLoc, diagnostic) << Name; 2339 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 2340 2341 return true; 2342} 2343 2344/// InjectAnonymousStructOrUnionMembers - Inject the members of the 2345/// anonymous struct or union AnonRecord into the owning context Owner 2346/// and scope S. This routine will be invoked just after we realize 2347/// that an unnamed union or struct is actually an anonymous union or 2348/// struct, e.g., 2349/// 2350/// @code 2351/// union { 2352/// int i; 2353/// float f; 2354/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 2355/// // f into the surrounding scope.x 2356/// @endcode 2357/// 2358/// This routine is recursive, injecting the names of nested anonymous 2359/// structs/unions into the owning context and scope as well. 2360static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 2361 DeclContext *Owner, 2362 RecordDecl *AnonRecord, 2363 AccessSpecifier AS, 2364 llvm::SmallVector<NamedDecl*, 2> &Chaining, 2365 bool MSAnonStruct) { 2366 unsigned diagKind 2367 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 2368 : diag::err_anonymous_struct_member_redecl; 2369 2370 bool Invalid = false; 2371 2372 // Look every FieldDecl and IndirectFieldDecl with a name. 2373 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 2374 DEnd = AnonRecord->decls_end(); 2375 D != DEnd; ++D) { 2376 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 2377 cast<NamedDecl>(*D)->getDeclName()) { 2378 ValueDecl *VD = cast<ValueDecl>(*D); 2379 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 2380 VD->getLocation(), diagKind)) { 2381 // C++ [class.union]p2: 2382 // The names of the members of an anonymous union shall be 2383 // distinct from the names of any other entity in the 2384 // scope in which the anonymous union is declared. 2385 Invalid = true; 2386 } else { 2387 // C++ [class.union]p2: 2388 // For the purpose of name lookup, after the anonymous union 2389 // definition, the members of the anonymous union are 2390 // considered to have been defined in the scope in which the 2391 // anonymous union is declared. 2392 unsigned OldChainingSize = Chaining.size(); 2393 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 2394 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 2395 PE = IF->chain_end(); PI != PE; ++PI) 2396 Chaining.push_back(*PI); 2397 else 2398 Chaining.push_back(VD); 2399 2400 assert(Chaining.size() >= 2); 2401 NamedDecl **NamedChain = 2402 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 2403 for (unsigned i = 0; i < Chaining.size(); i++) 2404 NamedChain[i] = Chaining[i]; 2405 2406 IndirectFieldDecl* IndirectField = 2407 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 2408 VD->getIdentifier(), VD->getType(), 2409 NamedChain, Chaining.size()); 2410 2411 IndirectField->setAccess(AS); 2412 IndirectField->setImplicit(); 2413 SemaRef.PushOnScopeChains(IndirectField, S); 2414 2415 // That includes picking up the appropriate access specifier. 2416 if (AS != AS_none) IndirectField->setAccess(AS); 2417 2418 Chaining.resize(OldChainingSize); 2419 } 2420 } 2421 } 2422 2423 return Invalid; 2424} 2425 2426/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 2427/// a VarDecl::StorageClass. Any error reporting is up to the caller: 2428/// illegal input values are mapped to SC_None. 2429static StorageClass 2430StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2431 switch (StorageClassSpec) { 2432 case DeclSpec::SCS_unspecified: return SC_None; 2433 case DeclSpec::SCS_extern: return SC_Extern; 2434 case DeclSpec::SCS_static: return SC_Static; 2435 case DeclSpec::SCS_auto: return SC_Auto; 2436 case DeclSpec::SCS_register: return SC_Register; 2437 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2438 // Illegal SCSs map to None: error reporting is up to the caller. 2439 case DeclSpec::SCS_mutable: // Fall through. 2440 case DeclSpec::SCS_typedef: return SC_None; 2441 } 2442 llvm_unreachable("unknown storage class specifier"); 2443} 2444 2445/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 2446/// a StorageClass. Any error reporting is up to the caller: 2447/// illegal input values are mapped to SC_None. 2448static StorageClass 2449StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2450 switch (StorageClassSpec) { 2451 case DeclSpec::SCS_unspecified: return SC_None; 2452 case DeclSpec::SCS_extern: return SC_Extern; 2453 case DeclSpec::SCS_static: return SC_Static; 2454 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2455 // Illegal SCSs map to None: error reporting is up to the caller. 2456 case DeclSpec::SCS_auto: // Fall through. 2457 case DeclSpec::SCS_mutable: // Fall through. 2458 case DeclSpec::SCS_register: // Fall through. 2459 case DeclSpec::SCS_typedef: return SC_None; 2460 } 2461 llvm_unreachable("unknown storage class specifier"); 2462} 2463 2464/// BuildAnonymousStructOrUnion - Handle the declaration of an 2465/// anonymous structure or union. Anonymous unions are a C++ feature 2466/// (C++ [class.union]) and a GNU C extension; anonymous structures 2467/// are a GNU C and GNU C++ extension. 2468Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2469 AccessSpecifier AS, 2470 RecordDecl *Record) { 2471 DeclContext *Owner = Record->getDeclContext(); 2472 2473 // Diagnose whether this anonymous struct/union is an extension. 2474 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2475 Diag(Record->getLocation(), diag::ext_anonymous_union); 2476 else if (!Record->isUnion()) 2477 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2478 2479 // C and C++ require different kinds of checks for anonymous 2480 // structs/unions. 2481 bool Invalid = false; 2482 if (getLangOptions().CPlusPlus) { 2483 const char* PrevSpec = 0; 2484 unsigned DiagID; 2485 // C++ [class.union]p3: 2486 // Anonymous unions declared in a named namespace or in the 2487 // global namespace shall be declared static. 2488 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2489 (isa<TranslationUnitDecl>(Owner) || 2490 (isa<NamespaceDecl>(Owner) && 2491 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2492 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2493 Invalid = true; 2494 2495 // Recover by adding 'static'. 2496 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2497 PrevSpec, DiagID, getLangOptions()); 2498 } 2499 // C++ [class.union]p3: 2500 // A storage class is not allowed in a declaration of an 2501 // anonymous union in a class scope. 2502 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2503 isa<RecordDecl>(Owner)) { 2504 Diag(DS.getStorageClassSpecLoc(), 2505 diag::err_anonymous_union_with_storage_spec); 2506 Invalid = true; 2507 2508 // Recover by removing the storage specifier. 2509 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2510 PrevSpec, DiagID, getLangOptions()); 2511 } 2512 2513 // Ignore const/volatile/restrict qualifiers. 2514 if (DS.getTypeQualifiers()) { 2515 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 2516 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified) 2517 << Record->isUnion() << 0 2518 << FixItHint::CreateRemoval(DS.getConstSpecLoc()); 2519 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 2520 Diag(DS.getVolatileSpecLoc(), diag::ext_anonymous_struct_union_qualified) 2521 << Record->isUnion() << 1 2522 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc()); 2523 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict) 2524 Diag(DS.getRestrictSpecLoc(), diag::ext_anonymous_struct_union_qualified) 2525 << Record->isUnion() << 2 2526 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc()); 2527 2528 DS.ClearTypeQualifiers(); 2529 } 2530 2531 // C++ [class.union]p2: 2532 // The member-specification of an anonymous union shall only 2533 // define non-static data members. [Note: nested types and 2534 // functions cannot be declared within an anonymous union. ] 2535 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2536 MemEnd = Record->decls_end(); 2537 Mem != MemEnd; ++Mem) { 2538 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2539 // C++ [class.union]p3: 2540 // An anonymous union shall not have private or protected 2541 // members (clause 11). 2542 assert(FD->getAccess() != AS_none); 2543 if (FD->getAccess() != AS_public) { 2544 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2545 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2546 Invalid = true; 2547 } 2548 2549 // C++ [class.union]p1 2550 // An object of a class with a non-trivial constructor, a non-trivial 2551 // copy constructor, a non-trivial destructor, or a non-trivial copy 2552 // assignment operator cannot be a member of a union, nor can an 2553 // array of such objects. 2554 if (!getLangOptions().CPlusPlus0x && CheckNontrivialField(FD)) 2555 Invalid = true; 2556 } else if ((*Mem)->isImplicit()) { 2557 // Any implicit members are fine. 2558 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2559 // This is a type that showed up in an 2560 // elaborated-type-specifier inside the anonymous struct or 2561 // union, but which actually declares a type outside of the 2562 // anonymous struct or union. It's okay. 2563 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2564 if (!MemRecord->isAnonymousStructOrUnion() && 2565 MemRecord->getDeclName()) { 2566 // Visual C++ allows type definition in anonymous struct or union. 2567 if (getLangOptions().Microsoft) 2568 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2569 << (int)Record->isUnion(); 2570 else { 2571 // This is a nested type declaration. 2572 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2573 << (int)Record->isUnion(); 2574 Invalid = true; 2575 } 2576 } 2577 } else if (isa<AccessSpecDecl>(*Mem)) { 2578 // Any access specifier is fine. 2579 } else { 2580 // We have something that isn't a non-static data 2581 // member. Complain about it. 2582 unsigned DK = diag::err_anonymous_record_bad_member; 2583 if (isa<TypeDecl>(*Mem)) 2584 DK = diag::err_anonymous_record_with_type; 2585 else if (isa<FunctionDecl>(*Mem)) 2586 DK = diag::err_anonymous_record_with_function; 2587 else if (isa<VarDecl>(*Mem)) 2588 DK = diag::err_anonymous_record_with_static; 2589 2590 // Visual C++ allows type definition in anonymous struct or union. 2591 if (getLangOptions().Microsoft && 2592 DK == diag::err_anonymous_record_with_type) 2593 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2594 << (int)Record->isUnion(); 2595 else { 2596 Diag((*Mem)->getLocation(), DK) 2597 << (int)Record->isUnion(); 2598 Invalid = true; 2599 } 2600 } 2601 } 2602 } 2603 2604 if (!Record->isUnion() && !Owner->isRecord()) { 2605 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2606 << (int)getLangOptions().CPlusPlus; 2607 Invalid = true; 2608 } 2609 2610 // Mock up a declarator. 2611 Declarator Dc(DS, Declarator::TypeNameContext); 2612 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2613 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2614 2615 // Create a declaration for this anonymous struct/union. 2616 NamedDecl *Anon = 0; 2617 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2618 Anon = FieldDecl::Create(Context, OwningClass, 2619 DS.getSourceRange().getBegin(), 2620 Record->getLocation(), 2621 /*IdentifierInfo=*/0, 2622 Context.getTypeDeclType(Record), 2623 TInfo, 2624 /*BitWidth=*/0, /*Mutable=*/false, 2625 /*HasInit=*/false); 2626 Anon->setAccess(AS); 2627 if (getLangOptions().CPlusPlus) 2628 FieldCollector->Add(cast<FieldDecl>(Anon)); 2629 } else { 2630 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2631 assert(SCSpec != DeclSpec::SCS_typedef && 2632 "Parser allowed 'typedef' as storage class VarDecl."); 2633 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2634 if (SCSpec == DeclSpec::SCS_mutable) { 2635 // mutable can only appear on non-static class members, so it's always 2636 // an error here 2637 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2638 Invalid = true; 2639 SC = SC_None; 2640 } 2641 SCSpec = DS.getStorageClassSpecAsWritten(); 2642 VarDecl::StorageClass SCAsWritten 2643 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2644 2645 Anon = VarDecl::Create(Context, Owner, 2646 DS.getSourceRange().getBegin(), 2647 Record->getLocation(), /*IdentifierInfo=*/0, 2648 Context.getTypeDeclType(Record), 2649 TInfo, SC, SCAsWritten); 2650 } 2651 Anon->setImplicit(); 2652 2653 // Add the anonymous struct/union object to the current 2654 // context. We'll be referencing this object when we refer to one of 2655 // its members. 2656 Owner->addDecl(Anon); 2657 2658 // Inject the members of the anonymous struct/union into the owning 2659 // context and into the identifier resolver chain for name lookup 2660 // purposes. 2661 llvm::SmallVector<NamedDecl*, 2> Chain; 2662 Chain.push_back(Anon); 2663 2664 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2665 Chain, false)) 2666 Invalid = true; 2667 2668 // Mark this as an anonymous struct/union type. Note that we do not 2669 // do this until after we have already checked and injected the 2670 // members of this anonymous struct/union type, because otherwise 2671 // the members could be injected twice: once by DeclContext when it 2672 // builds its lookup table, and once by 2673 // InjectAnonymousStructOrUnionMembers. 2674 Record->setAnonymousStructOrUnion(true); 2675 2676 if (Invalid) 2677 Anon->setInvalidDecl(); 2678 2679 return Anon; 2680} 2681 2682/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2683/// Microsoft C anonymous structure. 2684/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2685/// Example: 2686/// 2687/// struct A { int a; }; 2688/// struct B { struct A; int b; }; 2689/// 2690/// void foo() { 2691/// B var; 2692/// var.a = 3; 2693/// } 2694/// 2695Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2696 RecordDecl *Record) { 2697 2698 // If there is no Record, get the record via the typedef. 2699 if (!Record) 2700 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2701 2702 // Mock up a declarator. 2703 Declarator Dc(DS, Declarator::TypeNameContext); 2704 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2705 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2706 2707 // Create a declaration for this anonymous struct. 2708 NamedDecl* Anon = FieldDecl::Create(Context, 2709 cast<RecordDecl>(CurContext), 2710 DS.getSourceRange().getBegin(), 2711 DS.getSourceRange().getBegin(), 2712 /*IdentifierInfo=*/0, 2713 Context.getTypeDeclType(Record), 2714 TInfo, 2715 /*BitWidth=*/0, /*Mutable=*/false, 2716 /*HasInit=*/false); 2717 Anon->setImplicit(); 2718 2719 // Add the anonymous struct object to the current context. 2720 CurContext->addDecl(Anon); 2721 2722 // Inject the members of the anonymous struct into the current 2723 // context and into the identifier resolver chain for name lookup 2724 // purposes. 2725 llvm::SmallVector<NamedDecl*, 2> Chain; 2726 Chain.push_back(Anon); 2727 2728 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2729 Record->getDefinition(), 2730 AS_none, Chain, true)) 2731 Anon->setInvalidDecl(); 2732 2733 return Anon; 2734} 2735 2736/// GetNameForDeclarator - Determine the full declaration name for the 2737/// given Declarator. 2738DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2739 return GetNameFromUnqualifiedId(D.getName()); 2740} 2741 2742/// \brief Retrieves the declaration name from a parsed unqualified-id. 2743DeclarationNameInfo 2744Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2745 DeclarationNameInfo NameInfo; 2746 NameInfo.setLoc(Name.StartLocation); 2747 2748 switch (Name.getKind()) { 2749 2750 case UnqualifiedId::IK_Identifier: 2751 NameInfo.setName(Name.Identifier); 2752 NameInfo.setLoc(Name.StartLocation); 2753 return NameInfo; 2754 2755 case UnqualifiedId::IK_OperatorFunctionId: 2756 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2757 Name.OperatorFunctionId.Operator)); 2758 NameInfo.setLoc(Name.StartLocation); 2759 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2760 = Name.OperatorFunctionId.SymbolLocations[0]; 2761 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2762 = Name.EndLocation.getRawEncoding(); 2763 return NameInfo; 2764 2765 case UnqualifiedId::IK_LiteralOperatorId: 2766 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2767 Name.Identifier)); 2768 NameInfo.setLoc(Name.StartLocation); 2769 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2770 return NameInfo; 2771 2772 case UnqualifiedId::IK_ConversionFunctionId: { 2773 TypeSourceInfo *TInfo; 2774 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2775 if (Ty.isNull()) 2776 return DeclarationNameInfo(); 2777 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2778 Context.getCanonicalType(Ty))); 2779 NameInfo.setLoc(Name.StartLocation); 2780 NameInfo.setNamedTypeInfo(TInfo); 2781 return NameInfo; 2782 } 2783 2784 case UnqualifiedId::IK_ConstructorName: { 2785 TypeSourceInfo *TInfo; 2786 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2787 if (Ty.isNull()) 2788 return DeclarationNameInfo(); 2789 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2790 Context.getCanonicalType(Ty))); 2791 NameInfo.setLoc(Name.StartLocation); 2792 NameInfo.setNamedTypeInfo(TInfo); 2793 return NameInfo; 2794 } 2795 2796 case UnqualifiedId::IK_ConstructorTemplateId: { 2797 // In well-formed code, we can only have a constructor 2798 // template-id that refers to the current context, so go there 2799 // to find the actual type being constructed. 2800 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2801 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2802 return DeclarationNameInfo(); 2803 2804 // Determine the type of the class being constructed. 2805 QualType CurClassType = Context.getTypeDeclType(CurClass); 2806 2807 // FIXME: Check two things: that the template-id names the same type as 2808 // CurClassType, and that the template-id does not occur when the name 2809 // was qualified. 2810 2811 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2812 Context.getCanonicalType(CurClassType))); 2813 NameInfo.setLoc(Name.StartLocation); 2814 // FIXME: should we retrieve TypeSourceInfo? 2815 NameInfo.setNamedTypeInfo(0); 2816 return NameInfo; 2817 } 2818 2819 case UnqualifiedId::IK_DestructorName: { 2820 TypeSourceInfo *TInfo; 2821 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2822 if (Ty.isNull()) 2823 return DeclarationNameInfo(); 2824 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2825 Context.getCanonicalType(Ty))); 2826 NameInfo.setLoc(Name.StartLocation); 2827 NameInfo.setNamedTypeInfo(TInfo); 2828 return NameInfo; 2829 } 2830 2831 case UnqualifiedId::IK_TemplateId: { 2832 TemplateName TName = Name.TemplateId->Template.get(); 2833 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2834 return Context.getNameForTemplate(TName, TNameLoc); 2835 } 2836 2837 } // switch (Name.getKind()) 2838 2839 assert(false && "Unknown name kind"); 2840 return DeclarationNameInfo(); 2841} 2842 2843/// isNearlyMatchingFunction - Determine whether the C++ functions 2844/// Declaration and Definition are "nearly" matching. This heuristic 2845/// is used to improve diagnostics in the case where an out-of-line 2846/// function definition doesn't match any declaration within 2847/// the class or namespace. 2848static bool isNearlyMatchingFunction(ASTContext &Context, 2849 FunctionDecl *Declaration, 2850 FunctionDecl *Definition) { 2851 if (Declaration->param_size() != Definition->param_size()) 2852 return false; 2853 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2854 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2855 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2856 2857 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2858 DefParamTy.getNonReferenceType())) 2859 return false; 2860 } 2861 2862 return true; 2863} 2864 2865/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2866/// declarator needs to be rebuilt in the current instantiation. 2867/// Any bits of declarator which appear before the name are valid for 2868/// consideration here. That's specifically the type in the decl spec 2869/// and the base type in any member-pointer chunks. 2870static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2871 DeclarationName Name) { 2872 // The types we specifically need to rebuild are: 2873 // - typenames, typeofs, and decltypes 2874 // - types which will become injected class names 2875 // Of course, we also need to rebuild any type referencing such a 2876 // type. It's safest to just say "dependent", but we call out a 2877 // few cases here. 2878 2879 DeclSpec &DS = D.getMutableDeclSpec(); 2880 switch (DS.getTypeSpecType()) { 2881 case DeclSpec::TST_typename: 2882 case DeclSpec::TST_typeofType: 2883 case DeclSpec::TST_decltype: 2884 case DeclSpec::TST_underlyingType: { 2885 // Grab the type from the parser. 2886 TypeSourceInfo *TSI = 0; 2887 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2888 if (T.isNull() || !T->isDependentType()) break; 2889 2890 // Make sure there's a type source info. This isn't really much 2891 // of a waste; most dependent types should have type source info 2892 // attached already. 2893 if (!TSI) 2894 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2895 2896 // Rebuild the type in the current instantiation. 2897 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2898 if (!TSI) return true; 2899 2900 // Store the new type back in the decl spec. 2901 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2902 DS.UpdateTypeRep(LocType); 2903 break; 2904 } 2905 2906 case DeclSpec::TST_typeofExpr: { 2907 Expr *E = DS.getRepAsExpr(); 2908 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2909 if (Result.isInvalid()) return true; 2910 DS.UpdateExprRep(Result.get()); 2911 break; 2912 } 2913 2914 default: 2915 // Nothing to do for these decl specs. 2916 break; 2917 } 2918 2919 // It doesn't matter what order we do this in. 2920 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2921 DeclaratorChunk &Chunk = D.getTypeObject(I); 2922 2923 // The only type information in the declarator which can come 2924 // before the declaration name is the base type of a member 2925 // pointer. 2926 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2927 continue; 2928 2929 // Rebuild the scope specifier in-place. 2930 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2931 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2932 return true; 2933 } 2934 2935 return false; 2936} 2937 2938Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D, 2939 bool IsFunctionDefinition) { 2940 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), 2941 IsFunctionDefinition); 2942} 2943 2944/// DiagnoseClassNameShadow - Implement C++ [class.mem]p13: 2945/// If T is the name of a class, then each of the following shall have a 2946/// name different from T: 2947/// - every static data member of class T; 2948/// - every member function of class T 2949/// - every member of class T that is itself a type; 2950/// \returns true if the declaration name violates these rules. 2951bool Sema::DiagnoseClassNameShadow(DeclContext *DC, 2952 DeclarationNameInfo NameInfo) { 2953 DeclarationName Name = NameInfo.getName(); 2954 2955 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2956 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2957 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name; 2958 return true; 2959 } 2960 2961 return false; 2962} 2963 2964Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2965 MultiTemplateParamsArg TemplateParamLists, 2966 bool IsFunctionDefinition) { 2967 // TODO: consider using NameInfo for diagnostic. 2968 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2969 DeclarationName Name = NameInfo.getName(); 2970 2971 // All of these full declarators require an identifier. If it doesn't have 2972 // one, the ParsedFreeStandingDeclSpec action should be used. 2973 if (!Name) { 2974 if (!D.isInvalidType()) // Reject this if we think it is valid. 2975 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2976 diag::err_declarator_need_ident) 2977 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2978 return 0; 2979 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2980 return 0; 2981 2982 // The scope passed in may not be a decl scope. Zip up the scope tree until 2983 // we find one that is. 2984 while ((S->getFlags() & Scope::DeclScope) == 0 || 2985 (S->getFlags() & Scope::TemplateParamScope) != 0) 2986 S = S->getParent(); 2987 2988 DeclContext *DC = CurContext; 2989 if (D.getCXXScopeSpec().isInvalid()) 2990 D.setInvalidType(); 2991 else if (D.getCXXScopeSpec().isSet()) { 2992 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2993 UPPC_DeclarationQualifier)) 2994 return 0; 2995 2996 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2997 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2998 if (!DC) { 2999 // If we could not compute the declaration context, it's because the 3000 // declaration context is dependent but does not refer to a class, 3001 // class template, or class template partial specialization. Complain 3002 // and return early, to avoid the coming semantic disaster. 3003 Diag(D.getIdentifierLoc(), 3004 diag::err_template_qualified_declarator_no_match) 3005 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 3006 << D.getCXXScopeSpec().getRange(); 3007 return 0; 3008 } 3009 bool IsDependentContext = DC->isDependentContext(); 3010 3011 if (!IsDependentContext && 3012 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 3013 return 0; 3014 3015 if (isa<CXXRecordDecl>(DC)) { 3016 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 3017 Diag(D.getIdentifierLoc(), 3018 diag::err_member_def_undefined_record) 3019 << Name << DC << D.getCXXScopeSpec().getRange(); 3020 D.setInvalidType(); 3021 } else if (isa<CXXRecordDecl>(CurContext) && 3022 !D.getDeclSpec().isFriendSpecified()) { 3023 // The user provided a superfluous scope specifier inside a class 3024 // definition: 3025 // 3026 // class X { 3027 // void X::f(); 3028 // }; 3029 if (CurContext->Equals(DC)) 3030 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 3031 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 3032 else 3033 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 3034 << Name << D.getCXXScopeSpec().getRange(); 3035 3036 // Pretend that this qualifier was not here. 3037 D.getCXXScopeSpec().clear(); 3038 } 3039 } 3040 3041 // Check whether we need to rebuild the type of the given 3042 // declaration in the current instantiation. 3043 if (EnteringContext && IsDependentContext && 3044 TemplateParamLists.size() != 0) { 3045 ContextRAII SavedContext(*this, DC); 3046 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 3047 D.setInvalidType(); 3048 } 3049 } 3050 3051 if (DiagnoseClassNameShadow(DC, NameInfo)) 3052 // If this is a typedef, we'll end up spewing multiple diagnostics. 3053 // Just return early; it's safer. 3054 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 3055 return 0; 3056 3057 NamedDecl *New; 3058 3059 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 3060 QualType R = TInfo->getType(); 3061 3062 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 3063 UPPC_DeclarationType)) 3064 D.setInvalidType(); 3065 3066 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 3067 ForRedeclaration); 3068 3069 // See if this is a redefinition of a variable in the same scope. 3070 if (!D.getCXXScopeSpec().isSet()) { 3071 bool IsLinkageLookup = false; 3072 3073 // If the declaration we're planning to build will be a function 3074 // or object with linkage, then look for another declaration with 3075 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 3076 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 3077 /* Do nothing*/; 3078 else if (R->isFunctionType()) { 3079 if (CurContext->isFunctionOrMethod() || 3080 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 3081 IsLinkageLookup = true; 3082 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 3083 IsLinkageLookup = true; 3084 else if (CurContext->getRedeclContext()->isTranslationUnit() && 3085 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 3086 IsLinkageLookup = true; 3087 3088 if (IsLinkageLookup) 3089 Previous.clear(LookupRedeclarationWithLinkage); 3090 3091 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 3092 } else { // Something like "int foo::x;" 3093 LookupQualifiedName(Previous, DC); 3094 3095 // Don't consider using declarations as previous declarations for 3096 // out-of-line members. 3097 RemoveUsingDecls(Previous); 3098 3099 // C++ 7.3.1.2p2: 3100 // Members (including explicit specializations of templates) of a named 3101 // namespace can also be defined outside that namespace by explicit 3102 // qualification of the name being defined, provided that the entity being 3103 // defined was already declared in the namespace and the definition appears 3104 // after the point of declaration in a namespace that encloses the 3105 // declarations namespace. 3106 // 3107 // Note that we only check the context at this point. We don't yet 3108 // have enough information to make sure that PrevDecl is actually 3109 // the declaration we want to match. For example, given: 3110 // 3111 // class X { 3112 // void f(); 3113 // void f(float); 3114 // }; 3115 // 3116 // void X::f(int) { } // ill-formed 3117 // 3118 // In this case, PrevDecl will point to the overload set 3119 // containing the two f's declared in X, but neither of them 3120 // matches. 3121 3122 // First check whether we named the global scope. 3123 if (isa<TranslationUnitDecl>(DC)) { 3124 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 3125 << Name << D.getCXXScopeSpec().getRange(); 3126 } else { 3127 DeclContext *Cur = CurContext; 3128 while (isa<LinkageSpecDecl>(Cur)) 3129 Cur = Cur->getParent(); 3130 if (!Cur->Encloses(DC)) { 3131 // The qualifying scope doesn't enclose the original declaration. 3132 // Emit diagnostic based on current scope. 3133 SourceLocation L = D.getIdentifierLoc(); 3134 SourceRange R = D.getCXXScopeSpec().getRange(); 3135 if (isa<FunctionDecl>(Cur)) 3136 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 3137 else 3138 Diag(L, diag::err_invalid_declarator_scope) 3139 << Name << cast<NamedDecl>(DC) << R; 3140 D.setInvalidType(); 3141 } 3142 } 3143 } 3144 3145 if (Previous.isSingleResult() && 3146 Previous.getFoundDecl()->isTemplateParameter()) { 3147 // Maybe we will complain about the shadowed template parameter. 3148 if (!D.isInvalidType()) 3149 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 3150 Previous.getFoundDecl())) 3151 D.setInvalidType(); 3152 3153 // Just pretend that we didn't see the previous declaration. 3154 Previous.clear(); 3155 } 3156 3157 // In C++, the previous declaration we find might be a tag type 3158 // (class or enum). In this case, the new declaration will hide the 3159 // tag type. Note that this does does not apply if we're declaring a 3160 // typedef (C++ [dcl.typedef]p4). 3161 if (Previous.isSingleTagDecl() && 3162 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 3163 Previous.clear(); 3164 3165 bool Redeclaration = false; 3166 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 3167 if (TemplateParamLists.size()) { 3168 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 3169 return 0; 3170 } 3171 3172 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 3173 } else if (R->isFunctionType()) { 3174 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 3175 move(TemplateParamLists), 3176 IsFunctionDefinition, Redeclaration); 3177 } else { 3178 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 3179 move(TemplateParamLists), 3180 Redeclaration); 3181 } 3182 3183 if (New == 0) 3184 return 0; 3185 3186 // If this has an identifier and is not an invalid redeclaration or 3187 // function template specialization, add it to the scope stack. 3188 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 3189 PushOnScopeChains(New, S); 3190 3191 return New; 3192} 3193 3194/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3195/// types into constant array types in certain situations which would otherwise 3196/// be errors (for GCC compatibility). 3197static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3198 ASTContext &Context, 3199 bool &SizeIsNegative, 3200 llvm::APSInt &Oversized) { 3201 // This method tries to turn a variable array into a constant 3202 // array even when the size isn't an ICE. This is necessary 3203 // for compatibility with code that depends on gcc's buggy 3204 // constant expression folding, like struct {char x[(int)(char*)2];} 3205 SizeIsNegative = false; 3206 Oversized = 0; 3207 3208 if (T->isDependentType()) 3209 return QualType(); 3210 3211 QualifierCollector Qs; 3212 const Type *Ty = Qs.strip(T); 3213 3214 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 3215 QualType Pointee = PTy->getPointeeType(); 3216 QualType FixedType = 3217 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 3218 Oversized); 3219 if (FixedType.isNull()) return FixedType; 3220 FixedType = Context.getPointerType(FixedType); 3221 return Qs.apply(Context, FixedType); 3222 } 3223 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 3224 QualType Inner = PTy->getInnerType(); 3225 QualType FixedType = 3226 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 3227 Oversized); 3228 if (FixedType.isNull()) return FixedType; 3229 FixedType = Context.getParenType(FixedType); 3230 return Qs.apply(Context, FixedType); 3231 } 3232 3233 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3234 if (!VLATy) 3235 return QualType(); 3236 // FIXME: We should probably handle this case 3237 if (VLATy->getElementType()->isVariablyModifiedType()) 3238 return QualType(); 3239 3240 Expr::EvalResult EvalResult; 3241 if (!VLATy->getSizeExpr() || 3242 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 3243 !EvalResult.Val.isInt()) 3244 return QualType(); 3245 3246 // Check whether the array size is negative. 3247 llvm::APSInt &Res = EvalResult.Val.getInt(); 3248 if (Res.isSigned() && Res.isNegative()) { 3249 SizeIsNegative = true; 3250 return QualType(); 3251 } 3252 3253 // Check whether the array is too large to be addressed. 3254 unsigned ActiveSizeBits 3255 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 3256 Res); 3257 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 3258 Oversized = Res; 3259 return QualType(); 3260 } 3261 3262 return Context.getConstantArrayType(VLATy->getElementType(), 3263 Res, ArrayType::Normal, 0); 3264} 3265 3266/// \brief Register the given locally-scoped external C declaration so 3267/// that it can be found later for redeclarations 3268void 3269Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 3270 const LookupResult &Previous, 3271 Scope *S) { 3272 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 3273 "Decl is not a locally-scoped decl!"); 3274 // Note that we have a locally-scoped external with this name. 3275 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 3276 3277 if (!Previous.isSingleResult()) 3278 return; 3279 3280 NamedDecl *PrevDecl = Previous.getFoundDecl(); 3281 3282 // If there was a previous declaration of this variable, it may be 3283 // in our identifier chain. Update the identifier chain with the new 3284 // declaration. 3285 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 3286 // The previous declaration was found on the identifer resolver 3287 // chain, so remove it from its scope. 3288 while (S && !S->isDeclScope(PrevDecl)) 3289 S = S->getParent(); 3290 3291 if (S) 3292 S->RemoveDecl(PrevDecl); 3293 } 3294} 3295 3296/// \brief Diagnose function specifiers on a declaration of an identifier that 3297/// does not identify a function. 3298void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 3299 // FIXME: We should probably indicate the identifier in question to avoid 3300 // confusion for constructs like "inline int a(), b;" 3301 if (D.getDeclSpec().isInlineSpecified()) 3302 Diag(D.getDeclSpec().getInlineSpecLoc(), 3303 diag::err_inline_non_function); 3304 3305 if (D.getDeclSpec().isVirtualSpecified()) 3306 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3307 diag::err_virtual_non_function); 3308 3309 if (D.getDeclSpec().isExplicitSpecified()) 3310 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3311 diag::err_explicit_non_function); 3312} 3313 3314NamedDecl* 3315Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3316 QualType R, TypeSourceInfo *TInfo, 3317 LookupResult &Previous, bool &Redeclaration) { 3318 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 3319 if (D.getCXXScopeSpec().isSet()) { 3320 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 3321 << D.getCXXScopeSpec().getRange(); 3322 D.setInvalidType(); 3323 // Pretend we didn't see the scope specifier. 3324 DC = CurContext; 3325 Previous.clear(); 3326 } 3327 3328 if (getLangOptions().CPlusPlus) { 3329 // Check that there are no default arguments (C++ only). 3330 CheckExtraCXXDefaultArguments(D); 3331 } 3332 3333 DiagnoseFunctionSpecifiers(D); 3334 3335 if (D.getDeclSpec().isThreadSpecified()) 3336 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3337 3338 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 3339 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 3340 << D.getName().getSourceRange(); 3341 return 0; 3342 } 3343 3344 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 3345 if (!NewTD) return 0; 3346 3347 // Handle attributes prior to checking for duplicates in MergeVarDecl 3348 ProcessDeclAttributes(S, NewTD, D); 3349 3350 CheckTypedefForVariablyModifiedType(S, NewTD); 3351 3352 return ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration); 3353} 3354 3355void 3356Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) { 3357 // C99 6.7.7p2: If a typedef name specifies a variably modified type 3358 // then it shall have block scope. 3359 // Note that variably modified types must be fixed before merging the decl so 3360 // that redeclarations will match. 3361 QualType T = NewTD->getUnderlyingType(); 3362 if (T->isVariablyModifiedType()) { 3363 getCurFunction()->setHasBranchProtectedScope(); 3364 3365 if (S->getFnParent() == 0) { 3366 bool SizeIsNegative; 3367 llvm::APSInt Oversized; 3368 QualType FixedTy = 3369 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3370 Oversized); 3371 if (!FixedTy.isNull()) { 3372 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size); 3373 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 3374 } else { 3375 if (SizeIsNegative) 3376 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size); 3377 else if (T->isVariableArrayType()) 3378 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope); 3379 else if (Oversized.getBoolValue()) 3380 Diag(NewTD->getLocation(), diag::err_array_too_large) << Oversized.toString(10); 3381 else 3382 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope); 3383 NewTD->setInvalidDecl(); 3384 } 3385 } 3386 } 3387} 3388 3389 3390/// ActOnTypedefNameDecl - Perform semantic checking for a declaration which 3391/// declares a typedef-name, either using the 'typedef' type specifier or via 3392/// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'. 3393NamedDecl* 3394Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD, 3395 LookupResult &Previous, bool &Redeclaration) { 3396 // Merge the decl with the existing one if appropriate. If the decl is 3397 // in an outer scope, it isn't the same thing. 3398 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/ false, 3399 /*ExplicitInstantiationOrSpecialization=*/false); 3400 if (!Previous.empty()) { 3401 Redeclaration = true; 3402 MergeTypedefNameDecl(NewTD, Previous); 3403 } 3404 3405 // If this is the C FILE type, notify the AST context. 3406 if (IdentifierInfo *II = NewTD->getIdentifier()) 3407 if (!NewTD->isInvalidDecl() && 3408 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 3409 if (II->isStr("FILE")) 3410 Context.setFILEDecl(NewTD); 3411 else if (II->isStr("jmp_buf")) 3412 Context.setjmp_bufDecl(NewTD); 3413 else if (II->isStr("sigjmp_buf")) 3414 Context.setsigjmp_bufDecl(NewTD); 3415 else if (II->isStr("__builtin_va_list")) 3416 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 3417 } 3418 3419 return NewTD; 3420} 3421 3422/// \brief Determines whether the given declaration is an out-of-scope 3423/// previous declaration. 3424/// 3425/// This routine should be invoked when name lookup has found a 3426/// previous declaration (PrevDecl) that is not in the scope where a 3427/// new declaration by the same name is being introduced. If the new 3428/// declaration occurs in a local scope, previous declarations with 3429/// linkage may still be considered previous declarations (C99 3430/// 6.2.2p4-5, C++ [basic.link]p6). 3431/// 3432/// \param PrevDecl the previous declaration found by name 3433/// lookup 3434/// 3435/// \param DC the context in which the new declaration is being 3436/// declared. 3437/// 3438/// \returns true if PrevDecl is an out-of-scope previous declaration 3439/// for a new delcaration with the same name. 3440static bool 3441isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 3442 ASTContext &Context) { 3443 if (!PrevDecl) 3444 return false; 3445 3446 if (!PrevDecl->hasLinkage()) 3447 return false; 3448 3449 if (Context.getLangOptions().CPlusPlus) { 3450 // C++ [basic.link]p6: 3451 // If there is a visible declaration of an entity with linkage 3452 // having the same name and type, ignoring entities declared 3453 // outside the innermost enclosing namespace scope, the block 3454 // scope declaration declares that same entity and receives the 3455 // linkage of the previous declaration. 3456 DeclContext *OuterContext = DC->getRedeclContext(); 3457 if (!OuterContext->isFunctionOrMethod()) 3458 // This rule only applies to block-scope declarations. 3459 return false; 3460 3461 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 3462 if (PrevOuterContext->isRecord()) 3463 // We found a member function: ignore it. 3464 return false; 3465 3466 // Find the innermost enclosing namespace for the new and 3467 // previous declarations. 3468 OuterContext = OuterContext->getEnclosingNamespaceContext(); 3469 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 3470 3471 // The previous declaration is in a different namespace, so it 3472 // isn't the same function. 3473 if (!OuterContext->Equals(PrevOuterContext)) 3474 return false; 3475 } 3476 3477 return true; 3478} 3479 3480static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 3481 CXXScopeSpec &SS = D.getCXXScopeSpec(); 3482 if (!SS.isSet()) return; 3483 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 3484} 3485 3486bool Sema::inferObjCARCLifetime(ValueDecl *decl) { 3487 QualType type = decl->getType(); 3488 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime(); 3489 if (lifetime == Qualifiers::OCL_Autoreleasing) { 3490 // Various kinds of declaration aren't allowed to be __autoreleasing. 3491 unsigned kind = -1U; 3492 if (VarDecl *var = dyn_cast<VarDecl>(decl)) { 3493 if (var->hasAttr<BlocksAttr>()) 3494 kind = 0; // __block 3495 else if (!var->hasLocalStorage()) 3496 kind = 1; // global 3497 } else if (isa<ObjCIvarDecl>(decl)) { 3498 kind = 3; // ivar 3499 } else if (isa<FieldDecl>(decl)) { 3500 kind = 2; // field 3501 } 3502 3503 if (kind != -1U) { 3504 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var) 3505 << kind; 3506 } 3507 } else if (lifetime == Qualifiers::OCL_None) { 3508 // Try to infer lifetime. 3509 if (!type->isObjCLifetimeType()) 3510 return false; 3511 3512 lifetime = type->getObjCARCImplicitLifetime(); 3513 type = Context.getLifetimeQualifiedType(type, lifetime); 3514 decl->setType(type); 3515 } 3516 3517 if (VarDecl *var = dyn_cast<VarDecl>(decl)) { 3518 // Thread-local variables cannot have lifetime. 3519 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone && 3520 var->isThreadSpecified()) { 3521 Diag(var->getLocation(), diag::err_arc_thread_ownership) 3522 << var->getType(); 3523 return true; 3524 } 3525 } 3526 3527 return false; 3528} 3529 3530NamedDecl* 3531Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 3532 QualType R, TypeSourceInfo *TInfo, 3533 LookupResult &Previous, 3534 MultiTemplateParamsArg TemplateParamLists, 3535 bool &Redeclaration) { 3536 DeclarationName Name = GetNameForDeclarator(D).getName(); 3537 3538 // Check that there are no default arguments (C++ only). 3539 if (getLangOptions().CPlusPlus) 3540 CheckExtraCXXDefaultArguments(D); 3541 3542 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 3543 assert(SCSpec != DeclSpec::SCS_typedef && 3544 "Parser allowed 'typedef' as storage class VarDecl."); 3545 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 3546 if (SCSpec == DeclSpec::SCS_mutable) { 3547 // mutable can only appear on non-static class members, so it's always 3548 // an error here 3549 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 3550 D.setInvalidType(); 3551 SC = SC_None; 3552 } 3553 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3554 VarDecl::StorageClass SCAsWritten 3555 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3556 3557 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3558 if (!II) { 3559 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3560 << Name.getAsString(); 3561 return 0; 3562 } 3563 3564 DiagnoseFunctionSpecifiers(D); 3565 3566 if (!DC->isRecord() && S->getFnParent() == 0) { 3567 // C99 6.9p2: The storage-class specifiers auto and register shall not 3568 // appear in the declaration specifiers in an external declaration. 3569 if (SC == SC_Auto || SC == SC_Register) { 3570 3571 // If this is a register variable with an asm label specified, then this 3572 // is a GNU extension. 3573 if (SC == SC_Register && D.getAsmLabel()) 3574 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3575 else 3576 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3577 D.setInvalidType(); 3578 } 3579 } 3580 3581 bool isExplicitSpecialization = false; 3582 VarDecl *NewVD; 3583 if (!getLangOptions().CPlusPlus) { 3584 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3585 D.getIdentifierLoc(), II, 3586 R, TInfo, SC, SCAsWritten); 3587 3588 if (D.isInvalidType()) 3589 NewVD->setInvalidDecl(); 3590 } else { 3591 if (DC->isRecord() && !CurContext->isRecord()) { 3592 // This is an out-of-line definition of a static data member. 3593 if (SC == SC_Static) { 3594 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3595 diag::err_static_out_of_line) 3596 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3597 } else if (SC == SC_None) 3598 SC = SC_Static; 3599 } 3600 if (SC == SC_Static) { 3601 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3602 if (RD->isLocalClass()) 3603 Diag(D.getIdentifierLoc(), 3604 diag::err_static_data_member_not_allowed_in_local_class) 3605 << Name << RD->getDeclName(); 3606 3607 // C++ [class.union]p1: If a union contains a static data member, 3608 // the program is ill-formed. 3609 // 3610 // We also disallow static data members in anonymous structs. 3611 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3612 Diag(D.getIdentifierLoc(), 3613 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3614 << Name << RD->isUnion(); 3615 } 3616 } 3617 3618 // Match up the template parameter lists with the scope specifier, then 3619 // determine whether we have a template or a template specialization. 3620 isExplicitSpecialization = false; 3621 bool Invalid = false; 3622 if (TemplateParameterList *TemplateParams 3623 = MatchTemplateParametersToScopeSpecifier( 3624 D.getDeclSpec().getSourceRange().getBegin(), 3625 D.getIdentifierLoc(), 3626 D.getCXXScopeSpec(), 3627 TemplateParamLists.get(), 3628 TemplateParamLists.size(), 3629 /*never a friend*/ false, 3630 isExplicitSpecialization, 3631 Invalid)) { 3632 if (TemplateParams->size() > 0) { 3633 // There is no such thing as a variable template. 3634 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3635 << II 3636 << SourceRange(TemplateParams->getTemplateLoc(), 3637 TemplateParams->getRAngleLoc()); 3638 return 0; 3639 } else { 3640 // There is an extraneous 'template<>' for this variable. Complain 3641 // about it, but allow the declaration of the variable. 3642 Diag(TemplateParams->getTemplateLoc(), 3643 diag::err_template_variable_noparams) 3644 << II 3645 << SourceRange(TemplateParams->getTemplateLoc(), 3646 TemplateParams->getRAngleLoc()); 3647 } 3648 } 3649 3650 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3651 D.getIdentifierLoc(), II, 3652 R, TInfo, SC, SCAsWritten); 3653 3654 // If this decl has an auto type in need of deduction, make a note of the 3655 // Decl so we can diagnose uses of it in its own initializer. 3656 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3657 R->getContainedAutoType()) 3658 ParsingInitForAutoVars.insert(NewVD); 3659 3660 if (D.isInvalidType() || Invalid) 3661 NewVD->setInvalidDecl(); 3662 3663 SetNestedNameSpecifier(NewVD, D); 3664 3665 if (TemplateParamLists.size() > 0 && D.getCXXScopeSpec().isSet()) { 3666 NewVD->setTemplateParameterListsInfo(Context, 3667 TemplateParamLists.size(), 3668 TemplateParamLists.release()); 3669 } 3670 } 3671 3672 if (D.getDeclSpec().isThreadSpecified()) { 3673 if (NewVD->hasLocalStorage()) 3674 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3675 else if (!Context.Target.isTLSSupported()) 3676 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3677 else 3678 NewVD->setThreadSpecified(true); 3679 } 3680 3681 // Set the lexical context. If the declarator has a C++ scope specifier, the 3682 // lexical context will be different from the semantic context. 3683 NewVD->setLexicalDeclContext(CurContext); 3684 3685 // Handle attributes prior to checking for duplicates in MergeVarDecl 3686 ProcessDeclAttributes(S, NewVD, D); 3687 3688 // In auto-retain/release, infer strong retension for variables of 3689 // retainable type. 3690 if (getLangOptions().ObjCAutoRefCount && inferObjCARCLifetime(NewVD)) 3691 NewVD->setInvalidDecl(); 3692 3693 // Handle GNU asm-label extension (encoded as an attribute). 3694 if (Expr *E = (Expr*)D.getAsmLabel()) { 3695 // The parser guarantees this is a string. 3696 StringLiteral *SE = cast<StringLiteral>(E); 3697 llvm::StringRef Label = SE->getString(); 3698 if (S->getFnParent() != 0) { 3699 switch (SC) { 3700 case SC_None: 3701 case SC_Auto: 3702 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3703 break; 3704 case SC_Register: 3705 if (!Context.Target.isValidGCCRegisterName(Label)) 3706 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3707 break; 3708 case SC_Static: 3709 case SC_Extern: 3710 case SC_PrivateExtern: 3711 break; 3712 } 3713 } 3714 3715 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3716 Context, Label)); 3717 } 3718 3719 // Diagnose shadowed variables before filtering for scope. 3720 if (!D.getCXXScopeSpec().isSet()) 3721 CheckShadow(S, NewVD, Previous); 3722 3723 // Don't consider existing declarations that are in a different 3724 // scope and are out-of-semantic-context declarations (if the new 3725 // declaration has linkage). 3726 FilterLookupForScope(Previous, DC, S, NewVD->hasLinkage(), 3727 isExplicitSpecialization); 3728 3729 if (!getLangOptions().CPlusPlus) 3730 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3731 else { 3732 // Merge the decl with the existing one if appropriate. 3733 if (!Previous.empty()) { 3734 if (Previous.isSingleResult() && 3735 isa<FieldDecl>(Previous.getFoundDecl()) && 3736 D.getCXXScopeSpec().isSet()) { 3737 // The user tried to define a non-static data member 3738 // out-of-line (C++ [dcl.meaning]p1). 3739 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3740 << D.getCXXScopeSpec().getRange(); 3741 Previous.clear(); 3742 NewVD->setInvalidDecl(); 3743 } 3744 } else if (D.getCXXScopeSpec().isSet()) { 3745 // No previous declaration in the qualifying scope. 3746 Diag(D.getIdentifierLoc(), diag::err_no_member) 3747 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3748 << D.getCXXScopeSpec().getRange(); 3749 NewVD->setInvalidDecl(); 3750 } 3751 3752 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3753 3754 // This is an explicit specialization of a static data member. Check it. 3755 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3756 CheckMemberSpecialization(NewVD, Previous)) 3757 NewVD->setInvalidDecl(); 3758 } 3759 3760 // attributes declared post-definition are currently ignored 3761 // FIXME: This should be handled in attribute merging, not 3762 // here. 3763 if (Previous.isSingleResult()) { 3764 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3765 if (Def && (Def = Def->getDefinition()) && 3766 Def != NewVD && D.hasAttributes()) { 3767 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3768 Diag(Def->getLocation(), diag::note_previous_definition); 3769 } 3770 } 3771 3772 // If this is a locally-scoped extern C variable, update the map of 3773 // such variables. 3774 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3775 !NewVD->isInvalidDecl()) 3776 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3777 3778 // If there's a #pragma GCC visibility in scope, and this isn't a class 3779 // member, set the visibility of this variable. 3780 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3781 AddPushedVisibilityAttribute(NewVD); 3782 3783 MarkUnusedFileScopedDecl(NewVD); 3784 3785 return NewVD; 3786} 3787 3788/// \brief Diagnose variable or built-in function shadowing. Implements 3789/// -Wshadow. 3790/// 3791/// This method is called whenever a VarDecl is added to a "useful" 3792/// scope. 3793/// 3794/// \param S the scope in which the shadowing name is being declared 3795/// \param R the lookup of the name 3796/// 3797void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3798 // Return if warning is ignored. 3799 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3800 Diagnostic::Ignored) 3801 return; 3802 3803 // Don't diagnose declarations at file scope. 3804 if (D->hasGlobalStorage()) 3805 return; 3806 3807 DeclContext *NewDC = D->getDeclContext(); 3808 3809 // Only diagnose if we're shadowing an unambiguous field or variable. 3810 if (R.getResultKind() != LookupResult::Found) 3811 return; 3812 3813 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3814 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3815 return; 3816 3817 // Fields are not shadowed by variables in C++ static methods. 3818 if (isa<FieldDecl>(ShadowedDecl)) 3819 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3820 if (MD->isStatic()) 3821 return; 3822 3823 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3824 if (shadowedVar->isExternC()) { 3825 // For shadowing external vars, make sure that we point to the global 3826 // declaration, not a locally scoped extern declaration. 3827 for (VarDecl::redecl_iterator 3828 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3829 I != E; ++I) 3830 if (I->isFileVarDecl()) { 3831 ShadowedDecl = *I; 3832 break; 3833 } 3834 } 3835 3836 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3837 3838 // Only warn about certain kinds of shadowing for class members. 3839 if (NewDC && NewDC->isRecord()) { 3840 // In particular, don't warn about shadowing non-class members. 3841 if (!OldDC->isRecord()) 3842 return; 3843 3844 // TODO: should we warn about static data members shadowing 3845 // static data members from base classes? 3846 3847 // TODO: don't diagnose for inaccessible shadowed members. 3848 // This is hard to do perfectly because we might friend the 3849 // shadowing context, but that's just a false negative. 3850 } 3851 3852 // Determine what kind of declaration we're shadowing. 3853 unsigned Kind; 3854 if (isa<RecordDecl>(OldDC)) { 3855 if (isa<FieldDecl>(ShadowedDecl)) 3856 Kind = 3; // field 3857 else 3858 Kind = 2; // static data member 3859 } else if (OldDC->isFileContext()) 3860 Kind = 1; // global 3861 else 3862 Kind = 0; // local 3863 3864 DeclarationName Name = R.getLookupName(); 3865 3866 // Emit warning and note. 3867 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3868 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3869} 3870 3871/// \brief Check -Wshadow without the advantage of a previous lookup. 3872void Sema::CheckShadow(Scope *S, VarDecl *D) { 3873 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3874 Diagnostic::Ignored) 3875 return; 3876 3877 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3878 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3879 LookupName(R, S); 3880 CheckShadow(S, D, R); 3881} 3882 3883/// \brief Perform semantic checking on a newly-created variable 3884/// declaration. 3885/// 3886/// This routine performs all of the type-checking required for a 3887/// variable declaration once it has been built. It is used both to 3888/// check variables after they have been parsed and their declarators 3889/// have been translated into a declaration, and to check variables 3890/// that have been instantiated from a template. 3891/// 3892/// Sets NewVD->isInvalidDecl() if an error was encountered. 3893void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3894 LookupResult &Previous, 3895 bool &Redeclaration) { 3896 // If the decl is already known invalid, don't check it. 3897 if (NewVD->isInvalidDecl()) 3898 return; 3899 3900 QualType T = NewVD->getType(); 3901 3902 if (T->isObjCObjectType()) { 3903 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3904 return NewVD->setInvalidDecl(); 3905 } 3906 3907 // Emit an error if an address space was applied to decl with local storage. 3908 // This includes arrays of objects with address space qualifiers, but not 3909 // automatic variables that point to other address spaces. 3910 // ISO/IEC TR 18037 S5.1.2 3911 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3912 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3913 return NewVD->setInvalidDecl(); 3914 } 3915 3916 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3917 && !NewVD->hasAttr<BlocksAttr>()) { 3918 if (getLangOptions().getGCMode() != LangOptions::NonGC) 3919 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local); 3920 else 3921 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3922 } 3923 3924 bool isVM = T->isVariablyModifiedType(); 3925 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3926 NewVD->hasAttr<BlocksAttr>()) 3927 getCurFunction()->setHasBranchProtectedScope(); 3928 3929 if ((isVM && NewVD->hasLinkage()) || 3930 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3931 bool SizeIsNegative; 3932 llvm::APSInt Oversized; 3933 QualType FixedTy = 3934 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3935 Oversized); 3936 3937 if (FixedTy.isNull() && T->isVariableArrayType()) { 3938 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3939 // FIXME: This won't give the correct result for 3940 // int a[10][n]; 3941 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3942 3943 if (NewVD->isFileVarDecl()) 3944 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3945 << SizeRange; 3946 else if (NewVD->getStorageClass() == SC_Static) 3947 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3948 << SizeRange; 3949 else 3950 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3951 << SizeRange; 3952 return NewVD->setInvalidDecl(); 3953 } 3954 3955 if (FixedTy.isNull()) { 3956 if (NewVD->isFileVarDecl()) 3957 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3958 else 3959 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3960 return NewVD->setInvalidDecl(); 3961 } 3962 3963 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3964 NewVD->setType(FixedTy); 3965 } 3966 3967 if (Previous.empty() && NewVD->isExternC()) { 3968 // Since we did not find anything by this name and we're declaring 3969 // an extern "C" variable, look for a non-visible extern "C" 3970 // declaration with the same name. 3971 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3972 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3973 if (Pos != LocallyScopedExternalDecls.end()) 3974 Previous.addDecl(Pos->second); 3975 } 3976 3977 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3978 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3979 << T; 3980 return NewVD->setInvalidDecl(); 3981 } 3982 3983 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3984 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3985 return NewVD->setInvalidDecl(); 3986 } 3987 3988 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3989 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3990 return NewVD->setInvalidDecl(); 3991 } 3992 3993 // Function pointers and references cannot have qualified function type, only 3994 // function pointer-to-members can do that. 3995 QualType Pointee; 3996 unsigned PtrOrRef = 0; 3997 if (const PointerType *Ptr = T->getAs<PointerType>()) 3998 Pointee = Ptr->getPointeeType(); 3999 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 4000 Pointee = Ref->getPointeeType(); 4001 PtrOrRef = 1; 4002 } 4003 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 4004 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 4005 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 4006 << PtrOrRef; 4007 return NewVD->setInvalidDecl(); 4008 } 4009 4010 if (!Previous.empty()) { 4011 Redeclaration = true; 4012 MergeVarDecl(NewVD, Previous); 4013 } 4014} 4015 4016/// \brief Data used with FindOverriddenMethod 4017struct FindOverriddenMethodData { 4018 Sema *S; 4019 CXXMethodDecl *Method; 4020}; 4021 4022/// \brief Member lookup function that determines whether a given C++ 4023/// method overrides a method in a base class, to be used with 4024/// CXXRecordDecl::lookupInBases(). 4025static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 4026 CXXBasePath &Path, 4027 void *UserData) { 4028 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 4029 4030 FindOverriddenMethodData *Data 4031 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 4032 4033 DeclarationName Name = Data->Method->getDeclName(); 4034 4035 // FIXME: Do we care about other names here too? 4036 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4037 // We really want to find the base class destructor here. 4038 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 4039 CanQualType CT = Data->S->Context.getCanonicalType(T); 4040 4041 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 4042 } 4043 4044 for (Path.Decls = BaseRecord->lookup(Name); 4045 Path.Decls.first != Path.Decls.second; 4046 ++Path.Decls.first) { 4047 NamedDecl *D = *Path.Decls.first; 4048 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 4049 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 4050 return true; 4051 } 4052 } 4053 4054 return false; 4055} 4056 4057/// AddOverriddenMethods - See if a method overrides any in the base classes, 4058/// and if so, check that it's a valid override and remember it. 4059bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 4060 // Look for virtual methods in base classes that this method might override. 4061 CXXBasePaths Paths; 4062 FindOverriddenMethodData Data; 4063 Data.Method = MD; 4064 Data.S = this; 4065 bool AddedAny = false; 4066 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 4067 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 4068 E = Paths.found_decls_end(); I != E; ++I) { 4069 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 4070 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 4071 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 4072 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 4073 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 4074 AddedAny = true; 4075 } 4076 } 4077 } 4078 } 4079 4080 return AddedAny; 4081} 4082 4083static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 4084 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 4085 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 4086 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 4087 assert(!Prev.isAmbiguous() && 4088 "Cannot have an ambiguity in previous-declaration lookup"); 4089 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 4090 Func != FuncEnd; ++Func) { 4091 if (isa<FunctionDecl>(*Func) && 4092 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 4093 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 4094 } 4095} 4096 4097NamedDecl* 4098Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 4099 QualType R, TypeSourceInfo *TInfo, 4100 LookupResult &Previous, 4101 MultiTemplateParamsArg TemplateParamLists, 4102 bool IsFunctionDefinition, bool &Redeclaration) { 4103 assert(R.getTypePtr()->isFunctionType()); 4104 4105 // TODO: consider using NameInfo for diagnostic. 4106 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 4107 DeclarationName Name = NameInfo.getName(); 4108 FunctionDecl::StorageClass SC = SC_None; 4109 switch (D.getDeclSpec().getStorageClassSpec()) { 4110 default: assert(0 && "Unknown storage class!"); 4111 case DeclSpec::SCS_auto: 4112 case DeclSpec::SCS_register: 4113 case DeclSpec::SCS_mutable: 4114 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4115 diag::err_typecheck_sclass_func); 4116 D.setInvalidType(); 4117 break; 4118 case DeclSpec::SCS_unspecified: SC = SC_None; break; 4119 case DeclSpec::SCS_extern: SC = SC_Extern; break; 4120 case DeclSpec::SCS_static: { 4121 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 4122 // C99 6.7.1p5: 4123 // The declaration of an identifier for a function that has 4124 // block scope shall have no explicit storage-class specifier 4125 // other than extern 4126 // See also (C++ [dcl.stc]p4). 4127 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4128 diag::err_static_block_func); 4129 SC = SC_None; 4130 } else 4131 SC = SC_Static; 4132 break; 4133 } 4134 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 4135 } 4136 4137 if (D.getDeclSpec().isThreadSpecified()) 4138 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4139 4140 // Do not allow returning a objc interface by-value. 4141 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 4142 Diag(D.getIdentifierLoc(), 4143 diag::err_object_cannot_be_passed_returned_by_value) << 0 4144 << R->getAs<FunctionType>()->getResultType(); 4145 D.setInvalidType(); 4146 } 4147 4148 FunctionDecl *NewFD; 4149 bool isInline = D.getDeclSpec().isInlineSpecified(); 4150 bool isFriend = false; 4151 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 4152 FunctionDecl::StorageClass SCAsWritten 4153 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 4154 FunctionTemplateDecl *FunctionTemplate = 0; 4155 bool isExplicitSpecialization = false; 4156 bool isFunctionTemplateSpecialization = false; 4157 4158 if (!getLangOptions().CPlusPlus) { 4159 // Determine whether the function was written with a 4160 // prototype. This true when: 4161 // - there is a prototype in the declarator, or 4162 // - the type R of the function is some kind of typedef or other reference 4163 // to a type name (which eventually refers to a function type). 4164 bool HasPrototype = 4165 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 4166 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 4167 4168 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4169 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 4170 HasPrototype); 4171 if (D.isInvalidType()) 4172 NewFD->setInvalidDecl(); 4173 4174 // Set the lexical context. 4175 NewFD->setLexicalDeclContext(CurContext); 4176 // Filter out previous declarations that don't match the scope. 4177 FilterLookupForScope(Previous, DC, S, NewFD->hasLinkage(), 4178 /*ExplicitInstantiationOrSpecialization=*/false); 4179 } else { 4180 isFriend = D.getDeclSpec().isFriendSpecified(); 4181 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 4182 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 4183 bool isVirtualOkay = false; 4184 4185 // Check that the return type is not an abstract class type. 4186 // For record types, this is done by the AbstractClassUsageDiagnoser once 4187 // the class has been completely parsed. 4188 if (!DC->isRecord() && 4189 RequireNonAbstractType(D.getIdentifierLoc(), 4190 R->getAs<FunctionType>()->getResultType(), 4191 diag::err_abstract_type_in_decl, 4192 AbstractReturnType)) 4193 D.setInvalidType(); 4194 4195 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 4196 // This is a C++ constructor declaration. 4197 assert(DC->isRecord() && 4198 "Constructors can only be declared in a member context"); 4199 4200 R = CheckConstructorDeclarator(D, R, SC); 4201 4202 // Create the new declaration 4203 CXXConstructorDecl *NewCD = CXXConstructorDecl::Create( 4204 Context, 4205 cast<CXXRecordDecl>(DC), 4206 D.getSourceRange().getBegin(), 4207 NameInfo, R, TInfo, 4208 isExplicit, isInline, 4209 /*isImplicitlyDeclared=*/false); 4210 4211 NewFD = NewCD; 4212 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4213 // This is a C++ destructor declaration. 4214 if (DC->isRecord()) { 4215 R = CheckDestructorDeclarator(D, R, SC); 4216 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 4217 4218 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(Context, Record, 4219 D.getSourceRange().getBegin(), 4220 NameInfo, R, TInfo, 4221 isInline, 4222 /*isImplicitlyDeclared=*/false); 4223 NewFD = NewDD; 4224 isVirtualOkay = true; 4225 4226 // If the class is complete, then we now create the implicit exception 4227 // specification. If the class is incomplete or dependent, we can't do 4228 // it yet. 4229 if (getLangOptions().CPlusPlus0x && !Record->isDependentType() && 4230 Record->getDefinition() && !Record->isBeingDefined() && 4231 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) { 4232 AdjustDestructorExceptionSpec(Record, NewDD); 4233 } 4234 4235 } else { 4236 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 4237 4238 // Create a FunctionDecl to satisfy the function definition parsing 4239 // code path. 4240 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4241 D.getIdentifierLoc(), Name, R, TInfo, 4242 SC, SCAsWritten, isInline, 4243 /*hasPrototype=*/true); 4244 D.setInvalidType(); 4245 } 4246 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 4247 if (!DC->isRecord()) { 4248 Diag(D.getIdentifierLoc(), 4249 diag::err_conv_function_not_member); 4250 return 0; 4251 } 4252 4253 CheckConversionDeclarator(D, R, SC); 4254 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 4255 D.getSourceRange().getBegin(), 4256 NameInfo, R, TInfo, 4257 isInline, isExplicit, 4258 SourceLocation()); 4259 4260 isVirtualOkay = true; 4261 } else if (DC->isRecord()) { 4262 // If the of the function is the same as the name of the record, then this 4263 // must be an invalid constructor that has a return type. 4264 // (The parser checks for a return type and makes the declarator a 4265 // constructor if it has no return type). 4266 // must have an invalid constructor that has a return type 4267 if (Name.getAsIdentifierInfo() && 4268 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 4269 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 4270 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 4271 << SourceRange(D.getIdentifierLoc()); 4272 return 0; 4273 } 4274 4275 bool isStatic = SC == SC_Static; 4276 4277 // [class.free]p1: 4278 // Any allocation function for a class T is a static member 4279 // (even if not explicitly declared static). 4280 if (Name.getCXXOverloadedOperator() == OO_New || 4281 Name.getCXXOverloadedOperator() == OO_Array_New) 4282 isStatic = true; 4283 4284 // [class.free]p6 Any deallocation function for a class X is a static member 4285 // (even if not explicitly declared static). 4286 if (Name.getCXXOverloadedOperator() == OO_Delete || 4287 Name.getCXXOverloadedOperator() == OO_Array_Delete) 4288 isStatic = true; 4289 4290 // This is a C++ method declaration. 4291 CXXMethodDecl *NewMD = CXXMethodDecl::Create( 4292 Context, cast<CXXRecordDecl>(DC), 4293 D.getSourceRange().getBegin(), 4294 NameInfo, R, TInfo, 4295 isStatic, SCAsWritten, isInline, 4296 SourceLocation()); 4297 NewFD = NewMD; 4298 4299 isVirtualOkay = !isStatic; 4300 } else { 4301 // Determine whether the function was written with a 4302 // prototype. This true when: 4303 // - we're in C++ (where every function has a prototype), 4304 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 4305 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 4306 true/*HasPrototype*/); 4307 } 4308 4309 if (isFriend && !isInline && IsFunctionDefinition) { 4310 // C++ [class.friend]p5 4311 // A function can be defined in a friend declaration of a 4312 // class . . . . Such a function is implicitly inline. 4313 NewFD->setImplicitlyInline(); 4314 } 4315 4316 SetNestedNameSpecifier(NewFD, D); 4317 isExplicitSpecialization = false; 4318 isFunctionTemplateSpecialization = false; 4319 if (D.isInvalidType()) 4320 NewFD->setInvalidDecl(); 4321 4322 // Set the lexical context. If the declarator has a C++ 4323 // scope specifier, or is the object of a friend declaration, the 4324 // lexical context will be different from the semantic context. 4325 NewFD->setLexicalDeclContext(CurContext); 4326 4327 // Match up the template parameter lists with the scope specifier, then 4328 // determine whether we have a template or a template specialization. 4329 bool Invalid = false; 4330 if (TemplateParameterList *TemplateParams 4331 = MatchTemplateParametersToScopeSpecifier( 4332 D.getDeclSpec().getSourceRange().getBegin(), 4333 D.getIdentifierLoc(), 4334 D.getCXXScopeSpec(), 4335 TemplateParamLists.get(), 4336 TemplateParamLists.size(), 4337 isFriend, 4338 isExplicitSpecialization, 4339 Invalid)) { 4340 if (TemplateParams->size() > 0) { 4341 // This is a function template 4342 4343 // Check that we can declare a template here. 4344 if (CheckTemplateDeclScope(S, TemplateParams)) 4345 return 0; 4346 4347 // A destructor cannot be a template. 4348 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 4349 Diag(NewFD->getLocation(), diag::err_destructor_template); 4350 return 0; 4351 } 4352 4353 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 4354 NewFD->getLocation(), 4355 Name, TemplateParams, 4356 NewFD); 4357 FunctionTemplate->setLexicalDeclContext(CurContext); 4358 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 4359 4360 // For source fidelity, store the other template param lists. 4361 if (TemplateParamLists.size() > 1) { 4362 NewFD->setTemplateParameterListsInfo(Context, 4363 TemplateParamLists.size() - 1, 4364 TemplateParamLists.release()); 4365 } 4366 } else { 4367 // This is a function template specialization. 4368 isFunctionTemplateSpecialization = true; 4369 // For source fidelity, store all the template param lists. 4370 NewFD->setTemplateParameterListsInfo(Context, 4371 TemplateParamLists.size(), 4372 TemplateParamLists.release()); 4373 4374 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 4375 if (isFriend) { 4376 // We want to remove the "template<>", found here. 4377 SourceRange RemoveRange = TemplateParams->getSourceRange(); 4378 4379 // If we remove the template<> and the name is not a 4380 // template-id, we're actually silently creating a problem: 4381 // the friend declaration will refer to an untemplated decl, 4382 // and clearly the user wants a template specialization. So 4383 // we need to insert '<>' after the name. 4384 SourceLocation InsertLoc; 4385 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 4386 InsertLoc = D.getName().getSourceRange().getEnd(); 4387 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 4388 } 4389 4390 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 4391 << Name << RemoveRange 4392 << FixItHint::CreateRemoval(RemoveRange) 4393 << FixItHint::CreateInsertion(InsertLoc, "<>"); 4394 } 4395 } 4396 } 4397 else { 4398 // All template param lists were matched against the scope specifier: 4399 // this is NOT (an explicit specialization of) a template. 4400 if (TemplateParamLists.size() > 0) 4401 // For source fidelity, store all the template param lists. 4402 NewFD->setTemplateParameterListsInfo(Context, 4403 TemplateParamLists.size(), 4404 TemplateParamLists.release()); 4405 } 4406 4407 if (Invalid) { 4408 NewFD->setInvalidDecl(); 4409 if (FunctionTemplate) 4410 FunctionTemplate->setInvalidDecl(); 4411 } 4412 4413 // C++ [dcl.fct.spec]p5: 4414 // The virtual specifier shall only be used in declarations of 4415 // nonstatic class member functions that appear within a 4416 // member-specification of a class declaration; see 10.3. 4417 // 4418 if (isVirtual && !NewFD->isInvalidDecl()) { 4419 if (!isVirtualOkay) { 4420 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4421 diag::err_virtual_non_function); 4422 } else if (!CurContext->isRecord()) { 4423 // 'virtual' was specified outside of the class. 4424 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4425 diag::err_virtual_out_of_class) 4426 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 4427 } else if (NewFD->getDescribedFunctionTemplate()) { 4428 // C++ [temp.mem]p3: 4429 // A member function template shall not be virtual. 4430 Diag(D.getDeclSpec().getVirtualSpecLoc(), 4431 diag::err_virtual_member_function_template) 4432 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 4433 } else { 4434 // Okay: Add virtual to the method. 4435 NewFD->setVirtualAsWritten(true); 4436 } 4437 } 4438 4439 // C++ [dcl.fct.spec]p3: 4440 // The inline specifier shall not appear on a block scope function declaration. 4441 if (isInline && !NewFD->isInvalidDecl()) { 4442 if (CurContext->isFunctionOrMethod()) { 4443 // 'inline' is not allowed on block scope function declaration. 4444 Diag(D.getDeclSpec().getInlineSpecLoc(), 4445 diag::err_inline_declaration_block_scope) << Name 4446 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 4447 } 4448 } 4449 4450 // C++ [dcl.fct.spec]p6: 4451 // The explicit specifier shall be used only in the declaration of a 4452 // constructor or conversion function within its class definition; see 12.3.1 4453 // and 12.3.2. 4454 if (isExplicit && !NewFD->isInvalidDecl()) { 4455 if (!CurContext->isRecord()) { 4456 // 'explicit' was specified outside of the class. 4457 Diag(D.getDeclSpec().getExplicitSpecLoc(), 4458 diag::err_explicit_out_of_class) 4459 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 4460 } else if (!isa<CXXConstructorDecl>(NewFD) && 4461 !isa<CXXConversionDecl>(NewFD)) { 4462 // 'explicit' was specified on a function that wasn't a constructor 4463 // or conversion function. 4464 Diag(D.getDeclSpec().getExplicitSpecLoc(), 4465 diag::err_explicit_non_ctor_or_conv_function) 4466 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 4467 } 4468 } 4469 4470 // Filter out previous declarations that don't match the scope. 4471 FilterLookupForScope(Previous, DC, S, NewFD->hasLinkage(), 4472 isExplicitSpecialization || 4473 isFunctionTemplateSpecialization); 4474 4475 if (isFriend) { 4476 // For now, claim that the objects have no previous declaration. 4477 if (FunctionTemplate) { 4478 FunctionTemplate->setObjectOfFriendDecl(false); 4479 FunctionTemplate->setAccess(AS_public); 4480 } 4481 NewFD->setObjectOfFriendDecl(false); 4482 NewFD->setAccess(AS_public); 4483 } 4484 4485 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 4486 // A method is implicitly inline if it's defined in its class 4487 // definition. 4488 NewFD->setImplicitlyInline(); 4489 } 4490 4491 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 4492 !CurContext->isRecord()) { 4493 // C++ [class.static]p1: 4494 // A data or function member of a class may be declared static 4495 // in a class definition, in which case it is a static member of 4496 // the class. 4497 4498 // Complain about the 'static' specifier if it's on an out-of-line 4499 // member function definition. 4500 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4501 diag::err_static_out_of_line) 4502 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4503 } 4504 } 4505 4506 // Handle GNU asm-label extension (encoded as an attribute). 4507 if (Expr *E = (Expr*) D.getAsmLabel()) { 4508 // The parser guarantees this is a string. 4509 StringLiteral *SE = cast<StringLiteral>(E); 4510 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 4511 SE->getString())); 4512 } 4513 4514 // Copy the parameter declarations from the declarator D to the function 4515 // declaration NewFD, if they are available. First scavenge them into Params. 4516 llvm::SmallVector<ParmVarDecl*, 16> Params; 4517 if (D.isFunctionDeclarator()) { 4518 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 4519 4520 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 4521 // function that takes no arguments, not a function that takes a 4522 // single void argument. 4523 // We let through "const void" here because Sema::GetTypeForDeclarator 4524 // already checks for that case. 4525 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4526 FTI.ArgInfo[0].Param && 4527 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 4528 // Empty arg list, don't push any params. 4529 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 4530 4531 // In C++, the empty parameter-type-list must be spelled "void"; a 4532 // typedef of void is not permitted. 4533 if (getLangOptions().CPlusPlus && 4534 Param->getType().getUnqualifiedType() != Context.VoidTy) { 4535 bool IsTypeAlias = false; 4536 if (const TypedefType *TT = Param->getType()->getAs<TypedefType>()) 4537 IsTypeAlias = isa<TypeAliasDecl>(TT->getDecl()); 4538 else if (const TemplateSpecializationType *TST = 4539 Param->getType()->getAs<TemplateSpecializationType>()) 4540 IsTypeAlias = TST->isTypeAlias(); 4541 Diag(Param->getLocation(), diag::err_param_typedef_of_void) 4542 << IsTypeAlias; 4543 } 4544 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 4545 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 4546 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 4547 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 4548 Param->setDeclContext(NewFD); 4549 Params.push_back(Param); 4550 4551 if (Param->isInvalidDecl()) 4552 NewFD->setInvalidDecl(); 4553 } 4554 } 4555 4556 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 4557 // When we're declaring a function with a typedef, typeof, etc as in the 4558 // following example, we'll need to synthesize (unnamed) 4559 // parameters for use in the declaration. 4560 // 4561 // @code 4562 // typedef void fn(int); 4563 // fn f; 4564 // @endcode 4565 4566 // Synthesize a parameter for each argument type. 4567 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 4568 AE = FT->arg_type_end(); AI != AE; ++AI) { 4569 ParmVarDecl *Param = 4570 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 4571 Param->setScopeInfo(0, Params.size()); 4572 Params.push_back(Param); 4573 } 4574 } else { 4575 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 4576 "Should not need args for typedef of non-prototype fn"); 4577 } 4578 // Finally, we know we have the right number of parameters, install them. 4579 NewFD->setParams(Params.data(), Params.size()); 4580 4581 // Process the non-inheritable attributes on this declaration. 4582 ProcessDeclAttributes(S, NewFD, D, 4583 /*NonInheritable=*/true, /*Inheritable=*/false); 4584 4585 if (!getLangOptions().CPlusPlus) { 4586 // Perform semantic checking on the function declaration. 4587 bool isExplicitSpecialization=false; 4588 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4589 Redeclaration); 4590 assert((NewFD->isInvalidDecl() || !Redeclaration || 4591 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4592 "previous declaration set still overloaded"); 4593 } else { 4594 // If the declarator is a template-id, translate the parser's template 4595 // argument list into our AST format. 4596 bool HasExplicitTemplateArgs = false; 4597 TemplateArgumentListInfo TemplateArgs; 4598 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4599 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4600 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4601 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4602 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4603 TemplateId->getTemplateArgs(), 4604 TemplateId->NumArgs); 4605 translateTemplateArguments(TemplateArgsPtr, 4606 TemplateArgs); 4607 TemplateArgsPtr.release(); 4608 4609 HasExplicitTemplateArgs = true; 4610 4611 if (NewFD->isInvalidDecl()) { 4612 HasExplicitTemplateArgs = false; 4613 } else if (FunctionTemplate) { 4614 // Function template with explicit template arguments. 4615 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4616 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4617 4618 HasExplicitTemplateArgs = false; 4619 } else if (!isFunctionTemplateSpecialization && 4620 !D.getDeclSpec().isFriendSpecified()) { 4621 // We have encountered something that the user meant to be a 4622 // specialization (because it has explicitly-specified template 4623 // arguments) but that was not introduced with a "template<>" (or had 4624 // too few of them). 4625 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4626 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4627 << FixItHint::CreateInsertion( 4628 D.getDeclSpec().getSourceRange().getBegin(), 4629 "template<> "); 4630 isFunctionTemplateSpecialization = true; 4631 } else { 4632 // "friend void foo<>(int);" is an implicit specialization decl. 4633 isFunctionTemplateSpecialization = true; 4634 } 4635 } else if (isFriend && isFunctionTemplateSpecialization) { 4636 // This combination is only possible in a recovery case; the user 4637 // wrote something like: 4638 // template <> friend void foo(int); 4639 // which we're recovering from as if the user had written: 4640 // friend void foo<>(int); 4641 // Go ahead and fake up a template id. 4642 HasExplicitTemplateArgs = true; 4643 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4644 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4645 } 4646 4647 // If it's a friend (and only if it's a friend), it's possible 4648 // that either the specialized function type or the specialized 4649 // template is dependent, and therefore matching will fail. In 4650 // this case, don't check the specialization yet. 4651 if (isFunctionTemplateSpecialization && isFriend && 4652 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4653 assert(HasExplicitTemplateArgs && 4654 "friend function specialization without template args"); 4655 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4656 Previous)) 4657 NewFD->setInvalidDecl(); 4658 } else if (isFunctionTemplateSpecialization) { 4659 if (CurContext->isDependentContext() && CurContext->isRecord() 4660 && !isFriend) { 4661 Diag(NewFD->getLocation(), diag::err_function_specialization_in_class) 4662 << NewFD->getDeclName(); 4663 NewFD->setInvalidDecl(); 4664 return 0; 4665 } else if (CheckFunctionTemplateSpecialization(NewFD, 4666 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4667 Previous)) 4668 NewFD->setInvalidDecl(); 4669 4670 // C++ [dcl.stc]p1: 4671 // A storage-class-specifier shall not be specified in an explicit 4672 // specialization (14.7.3) 4673 if (SC != SC_None) { 4674 if (SC != NewFD->getStorageClass()) 4675 Diag(NewFD->getLocation(), 4676 diag::err_explicit_specialization_inconsistent_storage_class) 4677 << SC 4678 << FixItHint::CreateRemoval( 4679 D.getDeclSpec().getStorageClassSpecLoc()); 4680 4681 else 4682 Diag(NewFD->getLocation(), 4683 diag::ext_explicit_specialization_storage_class) 4684 << FixItHint::CreateRemoval( 4685 D.getDeclSpec().getStorageClassSpecLoc()); 4686 } 4687 4688 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4689 if (CheckMemberSpecialization(NewFD, Previous)) 4690 NewFD->setInvalidDecl(); 4691 } 4692 4693 // Perform semantic checking on the function declaration. 4694 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4695 Redeclaration); 4696 4697 assert((NewFD->isInvalidDecl() || !Redeclaration || 4698 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4699 "previous declaration set still overloaded"); 4700 4701 NamedDecl *PrincipalDecl = (FunctionTemplate 4702 ? cast<NamedDecl>(FunctionTemplate) 4703 : NewFD); 4704 4705 if (isFriend && Redeclaration) { 4706 AccessSpecifier Access = AS_public; 4707 if (!NewFD->isInvalidDecl()) 4708 Access = NewFD->getPreviousDeclaration()->getAccess(); 4709 4710 NewFD->setAccess(Access); 4711 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4712 4713 PrincipalDecl->setObjectOfFriendDecl(true); 4714 } 4715 4716 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4717 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4718 PrincipalDecl->setNonMemberOperator(); 4719 4720 // If we have a function template, check the template parameter 4721 // list. This will check and merge default template arguments. 4722 if (FunctionTemplate) { 4723 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4724 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4725 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4726 D.getDeclSpec().isFriendSpecified() 4727 ? (IsFunctionDefinition 4728 ? TPC_FriendFunctionTemplateDefinition 4729 : TPC_FriendFunctionTemplate) 4730 : (D.getCXXScopeSpec().isSet() && 4731 DC && DC->isRecord() && 4732 DC->isDependentContext()) 4733 ? TPC_ClassTemplateMember 4734 : TPC_FunctionTemplate); 4735 } 4736 4737 if (NewFD->isInvalidDecl()) { 4738 // Ignore all the rest of this. 4739 } else if (!Redeclaration) { 4740 // Fake up an access specifier if it's supposed to be a class member. 4741 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4742 NewFD->setAccess(AS_public); 4743 4744 // Qualified decls generally require a previous declaration. 4745 if (D.getCXXScopeSpec().isSet()) { 4746 // ...with the major exception of templated-scope or 4747 // dependent-scope friend declarations. 4748 4749 // TODO: we currently also suppress this check in dependent 4750 // contexts because (1) the parameter depth will be off when 4751 // matching friend templates and (2) we might actually be 4752 // selecting a friend based on a dependent factor. But there 4753 // are situations where these conditions don't apply and we 4754 // can actually do this check immediately. 4755 if (isFriend && 4756 (TemplateParamLists.size() || 4757 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4758 CurContext->isDependentContext())) { 4759 // ignore these 4760 } else { 4761 // The user tried to provide an out-of-line definition for a 4762 // function that is a member of a class or namespace, but there 4763 // was no such member function declared (C++ [class.mfct]p2, 4764 // C++ [namespace.memdef]p2). For example: 4765 // 4766 // class X { 4767 // void f() const; 4768 // }; 4769 // 4770 // void X::f() { } // ill-formed 4771 // 4772 // Complain about this problem, and attempt to suggest close 4773 // matches (e.g., those that differ only in cv-qualifiers and 4774 // whether the parameter types are references). 4775 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4776 << Name << DC << D.getCXXScopeSpec().getRange(); 4777 NewFD->setInvalidDecl(); 4778 4779 DiagnoseInvalidRedeclaration(*this, NewFD); 4780 } 4781 4782 // Unqualified local friend declarations are required to resolve 4783 // to something. 4784 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4785 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4786 NewFD->setInvalidDecl(); 4787 DiagnoseInvalidRedeclaration(*this, NewFD); 4788 } 4789 4790 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4791 !isFriend && !isFunctionTemplateSpecialization && 4792 !isExplicitSpecialization) { 4793 // An out-of-line member function declaration must also be a 4794 // definition (C++ [dcl.meaning]p1). 4795 // Note that this is not the case for explicit specializations of 4796 // function templates or member functions of class templates, per 4797 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4798 // for compatibility with old SWIG code which likes to generate them. 4799 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4800 << D.getCXXScopeSpec().getRange(); 4801 } 4802 } 4803 4804 4805 // Handle attributes. We need to have merged decls when handling attributes 4806 // (for example to check for conflicts, etc). 4807 // FIXME: This needs to happen before we merge declarations. Then, 4808 // let attribute merging cope with attribute conflicts. 4809 ProcessDeclAttributes(S, NewFD, D, 4810 /*NonInheritable=*/false, /*Inheritable=*/true); 4811 4812 // attributes declared post-definition are currently ignored 4813 // FIXME: This should happen during attribute merging 4814 if (Redeclaration && Previous.isSingleResult()) { 4815 const FunctionDecl *Def; 4816 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4817 if (PrevFD && PrevFD->isDefined(Def) && D.hasAttributes()) { 4818 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4819 Diag(Def->getLocation(), diag::note_previous_definition); 4820 } 4821 } 4822 4823 AddKnownFunctionAttributes(NewFD); 4824 4825 if (NewFD->hasAttr<OverloadableAttr>() && 4826 !NewFD->getType()->getAs<FunctionProtoType>()) { 4827 Diag(NewFD->getLocation(), 4828 diag::err_attribute_overloadable_no_prototype) 4829 << NewFD; 4830 4831 // Turn this into a variadic function with no parameters. 4832 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4833 FunctionProtoType::ExtProtoInfo EPI; 4834 EPI.Variadic = true; 4835 EPI.ExtInfo = FT->getExtInfo(); 4836 4837 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4838 NewFD->setType(R); 4839 } 4840 4841 // If there's a #pragma GCC visibility in scope, and this isn't a class 4842 // member, set the visibility of this function. 4843 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4844 AddPushedVisibilityAttribute(NewFD); 4845 4846 // If this is a locally-scoped extern C function, update the 4847 // map of such names. 4848 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4849 && !NewFD->isInvalidDecl()) 4850 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4851 4852 // Set this FunctionDecl's range up to the right paren. 4853 NewFD->setRangeEnd(D.getSourceRange().getEnd()); 4854 4855 if (getLangOptions().CPlusPlus) { 4856 if (FunctionTemplate) { 4857 if (NewFD->isInvalidDecl()) 4858 FunctionTemplate->setInvalidDecl(); 4859 return FunctionTemplate; 4860 } 4861 } 4862 4863 MarkUnusedFileScopedDecl(NewFD); 4864 4865 if (getLangOptions().CUDA) 4866 if (IdentifierInfo *II = NewFD->getIdentifier()) 4867 if (!NewFD->isInvalidDecl() && 4868 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4869 if (II->isStr("cudaConfigureCall")) { 4870 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4871 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4872 4873 Context.setcudaConfigureCallDecl(NewFD); 4874 } 4875 } 4876 4877 return NewFD; 4878} 4879 4880/// \brief Perform semantic checking of a new function declaration. 4881/// 4882/// Performs semantic analysis of the new function declaration 4883/// NewFD. This routine performs all semantic checking that does not 4884/// require the actual declarator involved in the declaration, and is 4885/// used both for the declaration of functions as they are parsed 4886/// (called via ActOnDeclarator) and for the declaration of functions 4887/// that have been instantiated via C++ template instantiation (called 4888/// via InstantiateDecl). 4889/// 4890/// \param IsExplicitSpecialiation whether this new function declaration is 4891/// an explicit specialization of the previous declaration. 4892/// 4893/// This sets NewFD->isInvalidDecl() to true if there was an error. 4894void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4895 LookupResult &Previous, 4896 bool IsExplicitSpecialization, 4897 bool &Redeclaration) { 4898 // If NewFD is already known erroneous, don't do any of this checking. 4899 if (NewFD->isInvalidDecl()) { 4900 // If this is a class member, mark the class invalid immediately. 4901 // This avoids some consistency errors later. 4902 if (isa<CXXMethodDecl>(NewFD)) 4903 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4904 4905 return; 4906 } 4907 4908 if (NewFD->getResultType()->isVariablyModifiedType()) { 4909 // Functions returning a variably modified type violate C99 6.7.5.2p2 4910 // because all functions have linkage. 4911 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4912 return NewFD->setInvalidDecl(); 4913 } 4914 4915 if (NewFD->isMain()) 4916 CheckMain(NewFD); 4917 4918 // Check for a previous declaration of this name. 4919 if (Previous.empty() && NewFD->isExternC()) { 4920 // Since we did not find anything by this name and we're declaring 4921 // an extern "C" function, look for a non-visible extern "C" 4922 // declaration with the same name. 4923 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4924 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4925 if (Pos != LocallyScopedExternalDecls.end()) 4926 Previous.addDecl(Pos->second); 4927 } 4928 4929 // Merge or overload the declaration with an existing declaration of 4930 // the same name, if appropriate. 4931 if (!Previous.empty()) { 4932 // Determine whether NewFD is an overload of PrevDecl or 4933 // a declaration that requires merging. If it's an overload, 4934 // there's no more work to do here; we'll just add the new 4935 // function to the scope. 4936 4937 NamedDecl *OldDecl = 0; 4938 if (!AllowOverloadingOfFunction(Previous, Context)) { 4939 Redeclaration = true; 4940 OldDecl = Previous.getFoundDecl(); 4941 } else { 4942 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4943 /*NewIsUsingDecl*/ false)) { 4944 case Ovl_Match: 4945 Redeclaration = true; 4946 break; 4947 4948 case Ovl_NonFunction: 4949 Redeclaration = true; 4950 break; 4951 4952 case Ovl_Overload: 4953 Redeclaration = false; 4954 break; 4955 } 4956 4957 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4958 // If a function name is overloadable in C, then every function 4959 // with that name must be marked "overloadable". 4960 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4961 << Redeclaration << NewFD; 4962 NamedDecl *OverloadedDecl = 0; 4963 if (Redeclaration) 4964 OverloadedDecl = OldDecl; 4965 else if (!Previous.empty()) 4966 OverloadedDecl = Previous.getRepresentativeDecl(); 4967 if (OverloadedDecl) 4968 Diag(OverloadedDecl->getLocation(), 4969 diag::note_attribute_overloadable_prev_overload); 4970 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4971 Context)); 4972 } 4973 } 4974 4975 if (Redeclaration) { 4976 // NewFD and OldDecl represent declarations that need to be 4977 // merged. 4978 if (MergeFunctionDecl(NewFD, OldDecl)) 4979 return NewFD->setInvalidDecl(); 4980 4981 Previous.clear(); 4982 Previous.addDecl(OldDecl); 4983 4984 if (FunctionTemplateDecl *OldTemplateDecl 4985 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4986 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4987 FunctionTemplateDecl *NewTemplateDecl 4988 = NewFD->getDescribedFunctionTemplate(); 4989 assert(NewTemplateDecl && "Template/non-template mismatch"); 4990 if (CXXMethodDecl *Method 4991 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4992 Method->setAccess(OldTemplateDecl->getAccess()); 4993 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4994 } 4995 4996 // If this is an explicit specialization of a member that is a function 4997 // template, mark it as a member specialization. 4998 if (IsExplicitSpecialization && 4999 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 5000 NewTemplateDecl->setMemberSpecialization(); 5001 assert(OldTemplateDecl->isMemberSpecialization()); 5002 } 5003 } else { 5004 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 5005 NewFD->setAccess(OldDecl->getAccess()); 5006 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 5007 } 5008 } 5009 } 5010 5011 // Semantic checking for this function declaration (in isolation). 5012 if (getLangOptions().CPlusPlus) { 5013 // C++-specific checks. 5014 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 5015 CheckConstructor(Constructor); 5016 } else if (CXXDestructorDecl *Destructor = 5017 dyn_cast<CXXDestructorDecl>(NewFD)) { 5018 CXXRecordDecl *Record = Destructor->getParent(); 5019 QualType ClassType = Context.getTypeDeclType(Record); 5020 5021 // FIXME: Shouldn't we be able to perform this check even when the class 5022 // type is dependent? Both gcc and edg can handle that. 5023 if (!ClassType->isDependentType()) { 5024 DeclarationName Name 5025 = Context.DeclarationNames.getCXXDestructorName( 5026 Context.getCanonicalType(ClassType)); 5027 if (NewFD->getDeclName() != Name) { 5028 Diag(NewFD->getLocation(), diag::err_destructor_name); 5029 return NewFD->setInvalidDecl(); 5030 } 5031 } 5032 } else if (CXXConversionDecl *Conversion 5033 = dyn_cast<CXXConversionDecl>(NewFD)) { 5034 ActOnConversionDeclarator(Conversion); 5035 } 5036 5037 // Find any virtual functions that this function overrides. 5038 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 5039 if (!Method->isFunctionTemplateSpecialization() && 5040 !Method->getDescribedFunctionTemplate()) { 5041 if (AddOverriddenMethods(Method->getParent(), Method)) { 5042 // If the function was marked as "static", we have a problem. 5043 if (NewFD->getStorageClass() == SC_Static) { 5044 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 5045 << NewFD->getDeclName(); 5046 for (CXXMethodDecl::method_iterator 5047 Overridden = Method->begin_overridden_methods(), 5048 OverriddenEnd = Method->end_overridden_methods(); 5049 Overridden != OverriddenEnd; 5050 ++Overridden) { 5051 Diag((*Overridden)->getLocation(), 5052 diag::note_overridden_virtual_function); 5053 } 5054 } 5055 } 5056 } 5057 } 5058 5059 // Extra checking for C++ overloaded operators (C++ [over.oper]). 5060 if (NewFD->isOverloadedOperator() && 5061 CheckOverloadedOperatorDeclaration(NewFD)) 5062 return NewFD->setInvalidDecl(); 5063 5064 // Extra checking for C++0x literal operators (C++0x [over.literal]). 5065 if (NewFD->getLiteralIdentifier() && 5066 CheckLiteralOperatorDeclaration(NewFD)) 5067 return NewFD->setInvalidDecl(); 5068 5069 // In C++, check default arguments now that we have merged decls. Unless 5070 // the lexical context is the class, because in this case this is done 5071 // during delayed parsing anyway. 5072 if (!CurContext->isRecord()) 5073 CheckCXXDefaultArguments(NewFD); 5074 5075 // If this function declares a builtin function, check the type of this 5076 // declaration against the expected type for the builtin. 5077 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 5078 ASTContext::GetBuiltinTypeError Error; 5079 QualType T = Context.GetBuiltinType(BuiltinID, Error); 5080 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 5081 // The type of this function differs from the type of the builtin, 5082 // so forget about the builtin entirely. 5083 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 5084 } 5085 } 5086 } 5087} 5088 5089void Sema::CheckMain(FunctionDecl* FD) { 5090 // C++ [basic.start.main]p3: A program that declares main to be inline 5091 // or static is ill-formed. 5092 // C99 6.7.4p4: In a hosted environment, the inline function specifier 5093 // shall not appear in a declaration of main. 5094 // static main is not an error under C99, but we should warn about it. 5095 bool isInline = FD->isInlineSpecified(); 5096 bool isStatic = FD->getStorageClass() == SC_Static; 5097 if (isInline || isStatic) { 5098 unsigned diagID = diag::warn_unusual_main_decl; 5099 if (isInline || getLangOptions().CPlusPlus) 5100 diagID = diag::err_unusual_main_decl; 5101 5102 int which = isStatic + (isInline << 1) - 1; 5103 Diag(FD->getLocation(), diagID) << which; 5104 } 5105 5106 QualType T = FD->getType(); 5107 assert(T->isFunctionType() && "function decl is not of function type"); 5108 const FunctionType* FT = T->getAs<FunctionType>(); 5109 5110 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 5111 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 5112 FD->setInvalidDecl(true); 5113 } 5114 5115 // Treat protoless main() as nullary. 5116 if (isa<FunctionNoProtoType>(FT)) return; 5117 5118 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 5119 unsigned nparams = FTP->getNumArgs(); 5120 assert(FD->getNumParams() == nparams); 5121 5122 bool HasExtraParameters = (nparams > 3); 5123 5124 // Darwin passes an undocumented fourth argument of type char**. If 5125 // other platforms start sprouting these, the logic below will start 5126 // getting shifty. 5127 if (nparams == 4 && Context.Target.getTriple().isOSDarwin()) 5128 HasExtraParameters = false; 5129 5130 if (HasExtraParameters) { 5131 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 5132 FD->setInvalidDecl(true); 5133 nparams = 3; 5134 } 5135 5136 // FIXME: a lot of the following diagnostics would be improved 5137 // if we had some location information about types. 5138 5139 QualType CharPP = 5140 Context.getPointerType(Context.getPointerType(Context.CharTy)); 5141 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 5142 5143 for (unsigned i = 0; i < nparams; ++i) { 5144 QualType AT = FTP->getArgType(i); 5145 5146 bool mismatch = true; 5147 5148 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 5149 mismatch = false; 5150 else if (Expected[i] == CharPP) { 5151 // As an extension, the following forms are okay: 5152 // char const ** 5153 // char const * const * 5154 // char * const * 5155 5156 QualifierCollector qs; 5157 const PointerType* PT; 5158 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 5159 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 5160 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 5161 qs.removeConst(); 5162 mismatch = !qs.empty(); 5163 } 5164 } 5165 5166 if (mismatch) { 5167 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 5168 // TODO: suggest replacing given type with expected type 5169 FD->setInvalidDecl(true); 5170 } 5171 } 5172 5173 if (nparams == 1 && !FD->isInvalidDecl()) { 5174 Diag(FD->getLocation(), diag::warn_main_one_arg); 5175 } 5176 5177 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 5178 Diag(FD->getLocation(), diag::err_main_template_decl); 5179 FD->setInvalidDecl(); 5180 } 5181} 5182 5183bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 5184 // FIXME: Need strict checking. In C89, we need to check for 5185 // any assignment, increment, decrement, function-calls, or 5186 // commas outside of a sizeof. In C99, it's the same list, 5187 // except that the aforementioned are allowed in unevaluated 5188 // expressions. Everything else falls under the 5189 // "may accept other forms of constant expressions" exception. 5190 // (We never end up here for C++, so the constant expression 5191 // rules there don't matter.) 5192 if (Init->isConstantInitializer(Context, false)) 5193 return false; 5194 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 5195 << Init->getSourceRange(); 5196 return true; 5197} 5198 5199namespace { 5200 // Visits an initialization expression to see if OrigDecl is evaluated in 5201 // its own initialization and throws a warning if it does. 5202 class SelfReferenceChecker 5203 : public EvaluatedExprVisitor<SelfReferenceChecker> { 5204 Sema &S; 5205 Decl *OrigDecl; 5206 5207 public: 5208 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited; 5209 5210 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context), 5211 S(S), OrigDecl(OrigDecl) { } 5212 5213 void VisitExpr(Expr *E) { 5214 if (isa<ObjCMessageExpr>(*E)) return; 5215 Inherited::VisitExpr(E); 5216 } 5217 5218 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 5219 CheckForSelfReference(E); 5220 Inherited::VisitImplicitCastExpr(E); 5221 } 5222 5223 void CheckForSelfReference(ImplicitCastExpr *E) { 5224 if (E->getCastKind() != CK_LValueToRValue) return; 5225 Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts(); 5226 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr); 5227 if (!DRE) return; 5228 Decl* ReferenceDecl = DRE->getDecl(); 5229 if (OrigDecl != ReferenceDecl) return; 5230 LookupResult Result(S, DRE->getNameInfo(), Sema::LookupOrdinaryName, 5231 Sema::NotForRedeclaration); 5232 S.DiagRuntimeBehavior(SubExpr->getLocStart(), SubExpr, 5233 S.PDiag(diag::warn_uninit_self_reference_in_init) 5234 << Result.getLookupName() 5235 << OrigDecl->getLocation() 5236 << SubExpr->getSourceRange()); 5237 } 5238 }; 5239} 5240 5241/// AddInitializerToDecl - Adds the initializer Init to the 5242/// declaration dcl. If DirectInit is true, this is C++ direct 5243/// initialization rather than copy initialization. 5244void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 5245 bool DirectInit, bool TypeMayContainAuto) { 5246 // If there is no declaration, there was an error parsing it. Just ignore 5247 // the initializer. 5248 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 5249 return; 5250 5251 // Check for self-references within variable initializers. 5252 if (VarDecl *vd = dyn_cast<VarDecl>(RealDecl)) { 5253 // Variables declared within a function/method body are handled 5254 // by a dataflow analysis. 5255 if (!vd->hasLocalStorage() && !vd->isStaticLocal()) 5256 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 5257 } 5258 else { 5259 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 5260 } 5261 5262 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 5263 // With declarators parsed the way they are, the parser cannot 5264 // distinguish between a normal initializer and a pure-specifier. 5265 // Thus this grotesque test. 5266 IntegerLiteral *IL; 5267 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 5268 Context.getCanonicalType(IL->getType()) == Context.IntTy) 5269 CheckPureMethod(Method, Init->getSourceRange()); 5270 else { 5271 Diag(Method->getLocation(), diag::err_member_function_initialization) 5272 << Method->getDeclName() << Init->getSourceRange(); 5273 Method->setInvalidDecl(); 5274 } 5275 return; 5276 } 5277 5278 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 5279 if (!VDecl) { 5280 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here"); 5281 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 5282 RealDecl->setInvalidDecl(); 5283 return; 5284 } 5285 5286 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 5287 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 5288 TypeSourceInfo *DeducedType = 0; 5289 if (!DeduceAutoType(VDecl->getTypeSourceInfo(), Init, DeducedType)) 5290 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 5291 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 5292 << Init->getSourceRange(); 5293 if (!DeducedType) { 5294 RealDecl->setInvalidDecl(); 5295 return; 5296 } 5297 VDecl->setTypeSourceInfo(DeducedType); 5298 VDecl->setType(DeducedType->getType()); 5299 5300 // In ARC, infer lifetime. 5301 if (getLangOptions().ObjCAutoRefCount && inferObjCARCLifetime(VDecl)) 5302 VDecl->setInvalidDecl(); 5303 5304 // If this is a redeclaration, check that the type we just deduced matches 5305 // the previously declared type. 5306 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 5307 MergeVarDeclTypes(VDecl, Old); 5308 } 5309 5310 5311 // A definition must end up with a complete type, which means it must be 5312 // complete with the restriction that an array type might be completed by the 5313 // initializer; note that later code assumes this restriction. 5314 QualType BaseDeclType = VDecl->getType(); 5315 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 5316 BaseDeclType = Array->getElementType(); 5317 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 5318 diag::err_typecheck_decl_incomplete_type)) { 5319 RealDecl->setInvalidDecl(); 5320 return; 5321 } 5322 5323 // The variable can not have an abstract class type. 5324 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 5325 diag::err_abstract_type_in_decl, 5326 AbstractVariableType)) 5327 VDecl->setInvalidDecl(); 5328 5329 const VarDecl *Def; 5330 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 5331 Diag(VDecl->getLocation(), diag::err_redefinition) 5332 << VDecl->getDeclName(); 5333 Diag(Def->getLocation(), diag::note_previous_definition); 5334 VDecl->setInvalidDecl(); 5335 return; 5336 } 5337 5338 const VarDecl* PrevInit = 0; 5339 if (getLangOptions().CPlusPlus) { 5340 // C++ [class.static.data]p4 5341 // If a static data member is of const integral or const 5342 // enumeration type, its declaration in the class definition can 5343 // specify a constant-initializer which shall be an integral 5344 // constant expression (5.19). In that case, the member can appear 5345 // in integral constant expressions. The member shall still be 5346 // defined in a namespace scope if it is used in the program and the 5347 // namespace scope definition shall not contain an initializer. 5348 // 5349 // We already performed a redefinition check above, but for static 5350 // data members we also need to check whether there was an in-class 5351 // declaration with an initializer. 5352 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 5353 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 5354 Diag(PrevInit->getLocation(), diag::note_previous_definition); 5355 return; 5356 } 5357 5358 if (VDecl->hasLocalStorage()) 5359 getCurFunction()->setHasBranchProtectedScope(); 5360 5361 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 5362 VDecl->setInvalidDecl(); 5363 return; 5364 } 5365 } 5366 5367 // Capture the variable that is being initialized and the style of 5368 // initialization. 5369 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 5370 5371 // FIXME: Poor source location information. 5372 InitializationKind Kind 5373 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 5374 Init->getLocStart(), 5375 Init->getLocEnd()) 5376 : InitializationKind::CreateCopy(VDecl->getLocation(), 5377 Init->getLocStart()); 5378 5379 // Get the decls type and save a reference for later, since 5380 // CheckInitializerTypes may change it. 5381 QualType DclT = VDecl->getType(), SavT = DclT; 5382 if (VDecl->isLocalVarDecl()) { 5383 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 5384 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 5385 VDecl->setInvalidDecl(); 5386 } else if (!VDecl->isInvalidDecl()) { 5387 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5388 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5389 MultiExprArg(*this, &Init, 1), 5390 &DclT); 5391 if (Result.isInvalid()) { 5392 VDecl->setInvalidDecl(); 5393 return; 5394 } 5395 5396 Init = Result.takeAs<Expr>(); 5397 5398 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 5399 // Don't check invalid declarations to avoid emitting useless diagnostics. 5400 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5401 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 5402 CheckForConstantInitializer(Init, DclT); 5403 } 5404 } 5405 } else if (VDecl->isStaticDataMember() && 5406 VDecl->getLexicalDeclContext()->isRecord()) { 5407 // This is an in-class initialization for a static data member, e.g., 5408 // 5409 // struct S { 5410 // static const int value = 17; 5411 // }; 5412 5413 // Try to perform the initialization regardless. 5414 if (!VDecl->isInvalidDecl()) { 5415 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5416 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5417 MultiExprArg(*this, &Init, 1), 5418 &DclT); 5419 if (Result.isInvalid()) { 5420 VDecl->setInvalidDecl(); 5421 return; 5422 } 5423 5424 Init = Result.takeAs<Expr>(); 5425 } 5426 5427 // C++ [class.mem]p4: 5428 // A member-declarator can contain a constant-initializer only 5429 // if it declares a static member (9.4) of const integral or 5430 // const enumeration type, see 9.4.2. 5431 QualType T = VDecl->getType(); 5432 5433 // Do nothing on dependent types. 5434 if (T->isDependentType()) { 5435 5436 // Require constness. 5437 } else if (!T.isConstQualified()) { 5438 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 5439 << Init->getSourceRange(); 5440 VDecl->setInvalidDecl(); 5441 5442 // We allow integer constant expressions in all cases. 5443 } else if (T->isIntegralOrEnumerationType()) { 5444 // Check whether the expression is a constant expression. 5445 SourceLocation Loc; 5446 if (Init->isValueDependent()) 5447 ; // Nothing to check. 5448 else if (Init->isIntegerConstantExpr(Context, &Loc)) 5449 ; // Ok, it's an ICE! 5450 else if (Init->isEvaluatable(Context)) { 5451 // If we can constant fold the initializer through heroics, accept it, 5452 // but report this as a use of an extension for -pedantic. 5453 Diag(Loc, diag::ext_in_class_initializer_non_constant) 5454 << Init->getSourceRange(); 5455 } else { 5456 // Otherwise, this is some crazy unknown case. Report the issue at the 5457 // location provided by the isIntegerConstantExpr failed check. 5458 Diag(Loc, diag::err_in_class_initializer_non_constant) 5459 << Init->getSourceRange(); 5460 VDecl->setInvalidDecl(); 5461 } 5462 5463 // We allow floating-point constants as an extension in C++03, and 5464 // C++0x has far more complicated rules that we don't really 5465 // implement fully. 5466 } else { 5467 bool Allowed = false; 5468 if (getLangOptions().CPlusPlus0x) { 5469 Allowed = T->isLiteralType(); 5470 } else if (T->isFloatingType()) { // also permits complex, which is ok 5471 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 5472 << T << Init->getSourceRange(); 5473 Allowed = true; 5474 } 5475 5476 if (!Allowed) { 5477 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 5478 << T << Init->getSourceRange(); 5479 VDecl->setInvalidDecl(); 5480 5481 // TODO: there are probably expressions that pass here that shouldn't. 5482 } else if (!Init->isValueDependent() && 5483 !Init->isConstantInitializer(Context, false)) { 5484 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 5485 << Init->getSourceRange(); 5486 VDecl->setInvalidDecl(); 5487 } 5488 } 5489 } else if (VDecl->isFileVarDecl()) { 5490 if (VDecl->getStorageClassAsWritten() == SC_Extern && 5491 (!getLangOptions().CPlusPlus || 5492 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 5493 Diag(VDecl->getLocation(), diag::warn_extern_init); 5494 if (!VDecl->isInvalidDecl()) { 5495 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 5496 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5497 MultiExprArg(*this, &Init, 1), 5498 &DclT); 5499 if (Result.isInvalid()) { 5500 VDecl->setInvalidDecl(); 5501 return; 5502 } 5503 5504 Init = Result.takeAs<Expr>(); 5505 } 5506 5507 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 5508 // Don't check invalid declarations to avoid emitting useless diagnostics. 5509 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5510 // C99 6.7.8p4. All file scoped initializers need to be constant. 5511 CheckForConstantInitializer(Init, DclT); 5512 } 5513 } 5514 // If the type changed, it means we had an incomplete type that was 5515 // completed by the initializer. For example: 5516 // int ary[] = { 1, 3, 5 }; 5517 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 5518 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 5519 VDecl->setType(DclT); 5520 Init->setType(DclT); 5521 } 5522 5523 5524 // If this variable is a local declaration with record type, make sure it 5525 // doesn't have a flexible member initialization. We only support this as a 5526 // global/static definition. 5527 if (VDecl->hasLocalStorage()) 5528 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 5529 if (RT->getDecl()->hasFlexibleArrayMember()) { 5530 // Check whether the initializer tries to initialize the flexible 5531 // array member itself to anything other than an empty initializer list. 5532 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 5533 unsigned Index = std::distance(RT->getDecl()->field_begin(), 5534 RT->getDecl()->field_end()) - 1; 5535 if (Index < ILE->getNumInits() && 5536 !(isa<InitListExpr>(ILE->getInit(Index)) && 5537 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 5538 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 5539 VDecl->setInvalidDecl(); 5540 } 5541 } 5542 } 5543 5544 // Check any implicit conversions within the expression. 5545 CheckImplicitConversions(Init, VDecl->getLocation()); 5546 5547 if (!VDecl->isInvalidDecl()) 5548 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init); 5549 5550 Init = MaybeCreateExprWithCleanups(Init); 5551 // Attach the initializer to the decl. 5552 VDecl->setInit(Init); 5553 5554 CheckCompleteVariableDeclaration(VDecl); 5555} 5556 5557/// ActOnInitializerError - Given that there was an error parsing an 5558/// initializer for the given declaration, try to return to some form 5559/// of sanity. 5560void Sema::ActOnInitializerError(Decl *D) { 5561 // Our main concern here is re-establishing invariants like "a 5562 // variable's type is either dependent or complete". 5563 if (!D || D->isInvalidDecl()) return; 5564 5565 VarDecl *VD = dyn_cast<VarDecl>(D); 5566 if (!VD) return; 5567 5568 // Auto types are meaningless if we can't make sense of the initializer. 5569 if (ParsingInitForAutoVars.count(D)) { 5570 D->setInvalidDecl(); 5571 return; 5572 } 5573 5574 QualType Ty = VD->getType(); 5575 if (Ty->isDependentType()) return; 5576 5577 // Require a complete type. 5578 if (RequireCompleteType(VD->getLocation(), 5579 Context.getBaseElementType(Ty), 5580 diag::err_typecheck_decl_incomplete_type)) { 5581 VD->setInvalidDecl(); 5582 return; 5583 } 5584 5585 // Require an abstract type. 5586 if (RequireNonAbstractType(VD->getLocation(), Ty, 5587 diag::err_abstract_type_in_decl, 5588 AbstractVariableType)) { 5589 VD->setInvalidDecl(); 5590 return; 5591 } 5592 5593 // Don't bother complaining about constructors or destructors, 5594 // though. 5595} 5596 5597void Sema::ActOnUninitializedDecl(Decl *RealDecl, 5598 bool TypeMayContainAuto) { 5599 // If there is no declaration, there was an error parsing it. Just ignore it. 5600 if (RealDecl == 0) 5601 return; 5602 5603 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 5604 QualType Type = Var->getType(); 5605 5606 // C++0x [dcl.spec.auto]p3 5607 if (TypeMayContainAuto && Type->getContainedAutoType()) { 5608 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 5609 << Var->getDeclName() << Type; 5610 Var->setInvalidDecl(); 5611 return; 5612 } 5613 5614 switch (Var->isThisDeclarationADefinition()) { 5615 case VarDecl::Definition: 5616 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 5617 break; 5618 5619 // We have an out-of-line definition of a static data member 5620 // that has an in-class initializer, so we type-check this like 5621 // a declaration. 5622 // 5623 // Fall through 5624 5625 case VarDecl::DeclarationOnly: 5626 // It's only a declaration. 5627 5628 // Block scope. C99 6.7p7: If an identifier for an object is 5629 // declared with no linkage (C99 6.2.2p6), the type for the 5630 // object shall be complete. 5631 if (!Type->isDependentType() && Var->isLocalVarDecl() && 5632 !Var->getLinkage() && !Var->isInvalidDecl() && 5633 RequireCompleteType(Var->getLocation(), Type, 5634 diag::err_typecheck_decl_incomplete_type)) 5635 Var->setInvalidDecl(); 5636 5637 // Make sure that the type is not abstract. 5638 if (!Type->isDependentType() && !Var->isInvalidDecl() && 5639 RequireNonAbstractType(Var->getLocation(), Type, 5640 diag::err_abstract_type_in_decl, 5641 AbstractVariableType)) 5642 Var->setInvalidDecl(); 5643 return; 5644 5645 case VarDecl::TentativeDefinition: 5646 // File scope. C99 6.9.2p2: A declaration of an identifier for an 5647 // object that has file scope without an initializer, and without a 5648 // storage-class specifier or with the storage-class specifier "static", 5649 // constitutes a tentative definition. Note: A tentative definition with 5650 // external linkage is valid (C99 6.2.2p5). 5651 if (!Var->isInvalidDecl()) { 5652 if (const IncompleteArrayType *ArrayT 5653 = Context.getAsIncompleteArrayType(Type)) { 5654 if (RequireCompleteType(Var->getLocation(), 5655 ArrayT->getElementType(), 5656 diag::err_illegal_decl_array_incomplete_type)) 5657 Var->setInvalidDecl(); 5658 } else if (Var->getStorageClass() == SC_Static) { 5659 // C99 6.9.2p3: If the declaration of an identifier for an object is 5660 // a tentative definition and has internal linkage (C99 6.2.2p3), the 5661 // declared type shall not be an incomplete type. 5662 // NOTE: code such as the following 5663 // static struct s; 5664 // struct s { int a; }; 5665 // is accepted by gcc. Hence here we issue a warning instead of 5666 // an error and we do not invalidate the static declaration. 5667 // NOTE: to avoid multiple warnings, only check the first declaration. 5668 if (Var->getPreviousDeclaration() == 0) 5669 RequireCompleteType(Var->getLocation(), Type, 5670 diag::ext_typecheck_decl_incomplete_type); 5671 } 5672 } 5673 5674 // Record the tentative definition; we're done. 5675 if (!Var->isInvalidDecl()) 5676 TentativeDefinitions.push_back(Var); 5677 return; 5678 } 5679 5680 // Provide a specific diagnostic for uninitialized variable 5681 // definitions with incomplete array type. 5682 if (Type->isIncompleteArrayType()) { 5683 Diag(Var->getLocation(), 5684 diag::err_typecheck_incomplete_array_needs_initializer); 5685 Var->setInvalidDecl(); 5686 return; 5687 } 5688 5689 // Provide a specific diagnostic for uninitialized variable 5690 // definitions with reference type. 5691 if (Type->isReferenceType()) { 5692 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5693 << Var->getDeclName() 5694 << SourceRange(Var->getLocation(), Var->getLocation()); 5695 Var->setInvalidDecl(); 5696 return; 5697 } 5698 5699 // Do not attempt to type-check the default initializer for a 5700 // variable with dependent type. 5701 if (Type->isDependentType()) 5702 return; 5703 5704 if (Var->isInvalidDecl()) 5705 return; 5706 5707 if (RequireCompleteType(Var->getLocation(), 5708 Context.getBaseElementType(Type), 5709 diag::err_typecheck_decl_incomplete_type)) { 5710 Var->setInvalidDecl(); 5711 return; 5712 } 5713 5714 // The variable can not have an abstract class type. 5715 if (RequireNonAbstractType(Var->getLocation(), Type, 5716 diag::err_abstract_type_in_decl, 5717 AbstractVariableType)) { 5718 Var->setInvalidDecl(); 5719 return; 5720 } 5721 5722 // Check for jumps past the implicit initializer. C++0x 5723 // clarifies that this applies to a "variable with automatic 5724 // storage duration", not a "local variable". 5725 // C++0x [stmt.dcl]p3 5726 // A program that jumps from a point where a variable with automatic 5727 // storage duration is not in scope to a point where it is in scope is 5728 // ill-formed unless the variable has scalar type, class type with a 5729 // trivial default constructor and a trivial destructor, a cv-qualified 5730 // version of one of these types, or an array of one of the preceding 5731 // types and is declared without an initializer. 5732 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) { 5733 if (const RecordType *Record 5734 = Context.getBaseElementType(Type)->getAs<RecordType>()) { 5735 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl()); 5736 if ((!getLangOptions().CPlusPlus0x && !CXXRecord->isPOD()) || 5737 (getLangOptions().CPlusPlus0x && 5738 (!CXXRecord->hasTrivialDefaultConstructor() || 5739 !CXXRecord->hasTrivialDestructor()))) 5740 getCurFunction()->setHasBranchProtectedScope(); 5741 } 5742 } 5743 5744 // C++03 [dcl.init]p9: 5745 // If no initializer is specified for an object, and the 5746 // object is of (possibly cv-qualified) non-POD class type (or 5747 // array thereof), the object shall be default-initialized; if 5748 // the object is of const-qualified type, the underlying class 5749 // type shall have a user-declared default 5750 // constructor. Otherwise, if no initializer is specified for 5751 // a non- static object, the object and its subobjects, if 5752 // any, have an indeterminate initial value); if the object 5753 // or any of its subobjects are of const-qualified type, the 5754 // program is ill-formed. 5755 // C++0x [dcl.init]p11: 5756 // If no initializer is specified for an object, the object is 5757 // default-initialized; [...]. 5758 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5759 InitializationKind Kind 5760 = InitializationKind::CreateDefault(Var->getLocation()); 5761 5762 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5763 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5764 MultiExprArg(*this, 0, 0)); 5765 if (Init.isInvalid()) 5766 Var->setInvalidDecl(); 5767 else if (Init.get()) 5768 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5769 5770 CheckCompleteVariableDeclaration(Var); 5771 } 5772} 5773 5774void Sema::ActOnCXXForRangeDecl(Decl *D) { 5775 VarDecl *VD = dyn_cast<VarDecl>(D); 5776 if (!VD) { 5777 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var); 5778 D->setInvalidDecl(); 5779 return; 5780 } 5781 5782 VD->setCXXForRangeDecl(true); 5783 5784 // for-range-declaration cannot be given a storage class specifier. 5785 int Error = -1; 5786 switch (VD->getStorageClassAsWritten()) { 5787 case SC_None: 5788 break; 5789 case SC_Extern: 5790 Error = 0; 5791 break; 5792 case SC_Static: 5793 Error = 1; 5794 break; 5795 case SC_PrivateExtern: 5796 Error = 2; 5797 break; 5798 case SC_Auto: 5799 Error = 3; 5800 break; 5801 case SC_Register: 5802 Error = 4; 5803 break; 5804 } 5805 // FIXME: constexpr isn't allowed here. 5806 //if (DS.isConstexprSpecified()) 5807 // Error = 5; 5808 if (Error != -1) { 5809 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class) 5810 << VD->getDeclName() << Error; 5811 D->setInvalidDecl(); 5812 } 5813} 5814 5815void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5816 if (var->isInvalidDecl()) return; 5817 5818 // In ARC, don't allow jumps past the implicit initialization of a 5819 // local retaining variable. 5820 if (getLangOptions().ObjCAutoRefCount && 5821 var->hasLocalStorage()) { 5822 switch (var->getType().getObjCLifetime()) { 5823 case Qualifiers::OCL_None: 5824 case Qualifiers::OCL_ExplicitNone: 5825 case Qualifiers::OCL_Autoreleasing: 5826 break; 5827 5828 case Qualifiers::OCL_Weak: 5829 case Qualifiers::OCL_Strong: 5830 getCurFunction()->setHasBranchProtectedScope(); 5831 break; 5832 } 5833 } 5834 5835 // All the following checks are C++ only. 5836 if (!getLangOptions().CPlusPlus) return; 5837 5838 QualType baseType = Context.getBaseElementType(var->getType()); 5839 if (baseType->isDependentType()) return; 5840 5841 // __block variables might require us to capture a copy-initializer. 5842 if (var->hasAttr<BlocksAttr>()) { 5843 // It's currently invalid to ever have a __block variable with an 5844 // array type; should we diagnose that here? 5845 5846 // Regardless, we don't want to ignore array nesting when 5847 // constructing this copy. 5848 QualType type = var->getType(); 5849 5850 if (type->isStructureOrClassType()) { 5851 SourceLocation poi = var->getLocation(); 5852 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5853 ExprResult result = 5854 PerformCopyInitialization( 5855 InitializedEntity::InitializeBlock(poi, type, false), 5856 poi, Owned(varRef)); 5857 if (!result.isInvalid()) { 5858 result = MaybeCreateExprWithCleanups(result); 5859 Expr *init = result.takeAs<Expr>(); 5860 Context.setBlockVarCopyInits(var, init); 5861 } 5862 } 5863 } 5864 5865 // Check for global constructors. 5866 if (!var->getDeclContext()->isDependentContext() && 5867 var->hasGlobalStorage() && 5868 !var->isStaticLocal() && 5869 var->getInit() && 5870 !var->getInit()->isConstantInitializer(Context, 5871 baseType->isReferenceType())) 5872 Diag(var->getLocation(), diag::warn_global_constructor) 5873 << var->getInit()->getSourceRange(); 5874 5875 // Require the destructor. 5876 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5877 FinalizeVarWithDestructor(var, recordType); 5878} 5879 5880/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5881/// any semantic actions necessary after any initializer has been attached. 5882void 5883Sema::FinalizeDeclaration(Decl *ThisDecl) { 5884 // Note that we are no longer parsing the initializer for this declaration. 5885 ParsingInitForAutoVars.erase(ThisDecl); 5886} 5887 5888Sema::DeclGroupPtrTy 5889Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5890 Decl **Group, unsigned NumDecls) { 5891 llvm::SmallVector<Decl*, 8> Decls; 5892 5893 if (DS.isTypeSpecOwned()) 5894 Decls.push_back(DS.getRepAsDecl()); 5895 5896 for (unsigned i = 0; i != NumDecls; ++i) 5897 if (Decl *D = Group[i]) 5898 Decls.push_back(D); 5899 5900 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5901 DS.getTypeSpecType() == DeclSpec::TST_auto); 5902} 5903 5904/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5905/// group, performing any necessary semantic checking. 5906Sema::DeclGroupPtrTy 5907Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5908 bool TypeMayContainAuto) { 5909 // C++0x [dcl.spec.auto]p7: 5910 // If the type deduced for the template parameter U is not the same in each 5911 // deduction, the program is ill-formed. 5912 // FIXME: When initializer-list support is added, a distinction is needed 5913 // between the deduced type U and the deduced type which 'auto' stands for. 5914 // auto a = 0, b = { 1, 2, 3 }; 5915 // is legal because the deduced type U is 'int' in both cases. 5916 if (TypeMayContainAuto && NumDecls > 1) { 5917 QualType Deduced; 5918 CanQualType DeducedCanon; 5919 VarDecl *DeducedDecl = 0; 5920 for (unsigned i = 0; i != NumDecls; ++i) { 5921 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5922 AutoType *AT = D->getType()->getContainedAutoType(); 5923 // Don't reissue diagnostics when instantiating a template. 5924 if (AT && D->isInvalidDecl()) 5925 break; 5926 if (AT && AT->isDeduced()) { 5927 QualType U = AT->getDeducedType(); 5928 CanQualType UCanon = Context.getCanonicalType(U); 5929 if (Deduced.isNull()) { 5930 Deduced = U; 5931 DeducedCanon = UCanon; 5932 DeducedDecl = D; 5933 } else if (DeducedCanon != UCanon) { 5934 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5935 diag::err_auto_different_deductions) 5936 << Deduced << DeducedDecl->getDeclName() 5937 << U << D->getDeclName() 5938 << DeducedDecl->getInit()->getSourceRange() 5939 << D->getInit()->getSourceRange(); 5940 D->setInvalidDecl(); 5941 break; 5942 } 5943 } 5944 } 5945 } 5946 } 5947 5948 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5949} 5950 5951 5952/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5953/// to introduce parameters into function prototype scope. 5954Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5955 const DeclSpec &DS = D.getDeclSpec(); 5956 5957 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5958 VarDecl::StorageClass StorageClass = SC_None; 5959 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5960 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5961 StorageClass = SC_Register; 5962 StorageClassAsWritten = SC_Register; 5963 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5964 Diag(DS.getStorageClassSpecLoc(), 5965 diag::err_invalid_storage_class_in_func_decl); 5966 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5967 } 5968 5969 if (D.getDeclSpec().isThreadSpecified()) 5970 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5971 5972 DiagnoseFunctionSpecifiers(D); 5973 5974 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5975 QualType parmDeclType = TInfo->getType(); 5976 5977 if (getLangOptions().CPlusPlus) { 5978 // Check that there are no default arguments inside the type of this 5979 // parameter. 5980 CheckExtraCXXDefaultArguments(D); 5981 5982 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5983 if (D.getCXXScopeSpec().isSet()) { 5984 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5985 << D.getCXXScopeSpec().getRange(); 5986 D.getCXXScopeSpec().clear(); 5987 } 5988 } 5989 5990 // Ensure we have a valid name 5991 IdentifierInfo *II = 0; 5992 if (D.hasName()) { 5993 II = D.getIdentifier(); 5994 if (!II) { 5995 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5996 << GetNameForDeclarator(D).getName().getAsString(); 5997 D.setInvalidType(true); 5998 } 5999 } 6000 6001 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 6002 if (II) { 6003 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 6004 ForRedeclaration); 6005 LookupName(R, S); 6006 if (R.isSingleResult()) { 6007 NamedDecl *PrevDecl = R.getFoundDecl(); 6008 if (PrevDecl->isTemplateParameter()) { 6009 // Maybe we will complain about the shadowed template parameter. 6010 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6011 // Just pretend that we didn't see the previous declaration. 6012 PrevDecl = 0; 6013 } else if (S->isDeclScope(PrevDecl)) { 6014 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 6015 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6016 6017 // Recover by removing the name 6018 II = 0; 6019 D.SetIdentifier(0, D.getIdentifierLoc()); 6020 D.setInvalidType(true); 6021 } 6022 } 6023 } 6024 6025 // Temporarily put parameter variables in the translation unit, not 6026 // the enclosing context. This prevents them from accidentally 6027 // looking like class members in C++. 6028 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 6029 D.getSourceRange().getBegin(), 6030 D.getIdentifierLoc(), II, 6031 parmDeclType, TInfo, 6032 StorageClass, StorageClassAsWritten); 6033 6034 if (D.isInvalidType()) 6035 New->setInvalidDecl(); 6036 6037 assert(S->isFunctionPrototypeScope()); 6038 assert(S->getFunctionPrototypeDepth() >= 1); 6039 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1, 6040 S->getNextFunctionPrototypeIndex()); 6041 6042 // Add the parameter declaration into this scope. 6043 S->AddDecl(New); 6044 if (II) 6045 IdResolver.AddDecl(New); 6046 6047 ProcessDeclAttributes(S, New, D); 6048 6049 if (New->hasAttr<BlocksAttr>()) { 6050 Diag(New->getLocation(), diag::err_block_on_nonlocal); 6051 } 6052 return New; 6053} 6054 6055/// \brief Synthesizes a variable for a parameter arising from a 6056/// typedef. 6057ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 6058 SourceLocation Loc, 6059 QualType T) { 6060 /* FIXME: setting StartLoc == Loc. 6061 Would it be worth to modify callers so as to provide proper source 6062 location for the unnamed parameters, embedding the parameter's type? */ 6063 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, 6064 T, Context.getTrivialTypeSourceInfo(T, Loc), 6065 SC_None, SC_None, 0); 6066 Param->setImplicit(); 6067 return Param; 6068} 6069 6070void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 6071 ParmVarDecl * const *ParamEnd) { 6072 // Don't diagnose unused-parameter errors in template instantiations; we 6073 // will already have done so in the template itself. 6074 if (!ActiveTemplateInstantiations.empty()) 6075 return; 6076 6077 for (; Param != ParamEnd; ++Param) { 6078 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 6079 !(*Param)->hasAttr<UnusedAttr>()) { 6080 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 6081 << (*Param)->getDeclName(); 6082 } 6083 } 6084} 6085 6086void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 6087 ParmVarDecl * const *ParamEnd, 6088 QualType ReturnTy, 6089 NamedDecl *D) { 6090 if (LangOpts.NumLargeByValueCopy == 0) // No check. 6091 return; 6092 6093 // Warn if the return value is pass-by-value and larger than the specified 6094 // threshold. 6095 if (ReturnTy.isPODType(Context)) { 6096 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 6097 if (Size > LangOpts.NumLargeByValueCopy) 6098 Diag(D->getLocation(), diag::warn_return_value_size) 6099 << D->getDeclName() << Size; 6100 } 6101 6102 // Warn if any parameter is pass-by-value and larger than the specified 6103 // threshold. 6104 for (; Param != ParamEnd; ++Param) { 6105 QualType T = (*Param)->getType(); 6106 if (!T.isPODType(Context)) 6107 continue; 6108 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 6109 if (Size > LangOpts.NumLargeByValueCopy) 6110 Diag((*Param)->getLocation(), diag::warn_parameter_size) 6111 << (*Param)->getDeclName() << Size; 6112 } 6113} 6114 6115ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, 6116 SourceLocation NameLoc, IdentifierInfo *Name, 6117 QualType T, TypeSourceInfo *TSInfo, 6118 VarDecl::StorageClass StorageClass, 6119 VarDecl::StorageClass StorageClassAsWritten) { 6120 // In ARC, infer a lifetime qualifier for appropriate parameter types. 6121 if (getLangOptions().ObjCAutoRefCount && 6122 T.getObjCLifetime() == Qualifiers::OCL_None && 6123 T->isObjCLifetimeType()) { 6124 6125 Qualifiers::ObjCLifetime lifetime; 6126 6127 // Special cases for arrays: 6128 // - if it's const, use __unsafe_unretained 6129 // - otherwise, it's an error 6130 if (T->isArrayType()) { 6131 if (!T.isConstQualified()) { 6132 Diag(NameLoc, diag::err_arc_array_param_no_ownership) 6133 << TSInfo->getTypeLoc().getSourceRange(); 6134 } 6135 lifetime = Qualifiers::OCL_ExplicitNone; 6136 } else { 6137 lifetime = T->getObjCARCImplicitLifetime(); 6138 } 6139 T = Context.getLifetimeQualifiedType(T, lifetime); 6140 } 6141 6142 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, 6143 adjustParameterType(T), TSInfo, 6144 StorageClass, StorageClassAsWritten, 6145 0); 6146 6147 // Parameters can not be abstract class types. 6148 // For record types, this is done by the AbstractClassUsageDiagnoser once 6149 // the class has been completely parsed. 6150 if (!CurContext->isRecord() && 6151 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 6152 AbstractParamType)) 6153 New->setInvalidDecl(); 6154 6155 // Parameter declarators cannot be interface types. All ObjC objects are 6156 // passed by reference. 6157 if (T->isObjCObjectType()) { 6158 Diag(NameLoc, 6159 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 6160 New->setInvalidDecl(); 6161 } 6162 6163 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 6164 // duration shall not be qualified by an address-space qualifier." 6165 // Since all parameters have automatic store duration, they can not have 6166 // an address space. 6167 if (T.getAddressSpace() != 0) { 6168 Diag(NameLoc, diag::err_arg_with_address_space); 6169 New->setInvalidDecl(); 6170 } 6171 6172 return New; 6173} 6174 6175void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 6176 SourceLocation LocAfterDecls) { 6177 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 6178 6179 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 6180 // for a K&R function. 6181 if (!FTI.hasPrototype) { 6182 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 6183 --i; 6184 if (FTI.ArgInfo[i].Param == 0) { 6185 llvm::SmallString<256> Code; 6186 llvm::raw_svector_ostream(Code) << " int " 6187 << FTI.ArgInfo[i].Ident->getName() 6188 << ";\n"; 6189 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 6190 << FTI.ArgInfo[i].Ident 6191 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 6192 6193 // Implicitly declare the argument as type 'int' for lack of a better 6194 // type. 6195 AttributeFactory attrs; 6196 DeclSpec DS(attrs); 6197 const char* PrevSpec; // unused 6198 unsigned DiagID; // unused 6199 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 6200 PrevSpec, DiagID); 6201 Declarator ParamD(DS, Declarator::KNRTypeListContext); 6202 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 6203 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 6204 } 6205 } 6206 } 6207} 6208 6209Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 6210 Declarator &D) { 6211 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 6212 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 6213 Scope *ParentScope = FnBodyScope->getParent(); 6214 6215 Decl *DP = HandleDeclarator(ParentScope, D, 6216 MultiTemplateParamsArg(*this), 6217 /*IsFunctionDefinition=*/true); 6218 return ActOnStartOfFunctionDef(FnBodyScope, DP); 6219} 6220 6221static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 6222 // Don't warn about invalid declarations. 6223 if (FD->isInvalidDecl()) 6224 return false; 6225 6226 // Or declarations that aren't global. 6227 if (!FD->isGlobal()) 6228 return false; 6229 6230 // Don't warn about C++ member functions. 6231 if (isa<CXXMethodDecl>(FD)) 6232 return false; 6233 6234 // Don't warn about 'main'. 6235 if (FD->isMain()) 6236 return false; 6237 6238 // Don't warn about inline functions. 6239 if (FD->isInlined()) 6240 return false; 6241 6242 // Don't warn about function templates. 6243 if (FD->getDescribedFunctionTemplate()) 6244 return false; 6245 6246 // Don't warn about function template specializations. 6247 if (FD->isFunctionTemplateSpecialization()) 6248 return false; 6249 6250 bool MissingPrototype = true; 6251 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 6252 Prev; Prev = Prev->getPreviousDeclaration()) { 6253 // Ignore any declarations that occur in function or method 6254 // scope, because they aren't visible from the header. 6255 if (Prev->getDeclContext()->isFunctionOrMethod()) 6256 continue; 6257 6258 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 6259 break; 6260 } 6261 6262 return MissingPrototype; 6263} 6264 6265void Sema::CheckForFunctionRedefinition(FunctionDecl *FD) { 6266 // Don't complain if we're in GNU89 mode and the previous definition 6267 // was an extern inline function. 6268 const FunctionDecl *Definition; 6269 if (FD->isDefined(Definition) && 6270 !canRedefineFunction(Definition, getLangOptions())) { 6271 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 6272 Definition->getStorageClass() == SC_Extern) 6273 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 6274 << FD->getDeclName() << getLangOptions().CPlusPlus; 6275 else 6276 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 6277 Diag(Definition->getLocation(), diag::note_previous_definition); 6278 } 6279} 6280 6281Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 6282 // Clear the last template instantiation error context. 6283 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 6284 6285 if (!D) 6286 return D; 6287 FunctionDecl *FD = 0; 6288 6289 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 6290 FD = FunTmpl->getTemplatedDecl(); 6291 else 6292 FD = cast<FunctionDecl>(D); 6293 6294 // Enter a new function scope 6295 PushFunctionScope(); 6296 6297 // See if this is a redefinition. 6298 if (!FD->isLateTemplateParsed()) 6299 CheckForFunctionRedefinition(FD); 6300 6301 // Builtin functions cannot be defined. 6302 if (unsigned BuiltinID = FD->getBuiltinID()) { 6303 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 6304 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 6305 FD->setInvalidDecl(); 6306 } 6307 } 6308 6309 // The return type of a function definition must be complete 6310 // (C99 6.9.1p3, C++ [dcl.fct]p6). 6311 QualType ResultType = FD->getResultType(); 6312 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 6313 !FD->isInvalidDecl() && 6314 RequireCompleteType(FD->getLocation(), ResultType, 6315 diag::err_func_def_incomplete_result)) 6316 FD->setInvalidDecl(); 6317 6318 // GNU warning -Wmissing-prototypes: 6319 // Warn if a global function is defined without a previous 6320 // prototype declaration. This warning is issued even if the 6321 // definition itself provides a prototype. The aim is to detect 6322 // global functions that fail to be declared in header files. 6323 if (ShouldWarnAboutMissingPrototype(FD)) 6324 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 6325 6326 if (FnBodyScope) 6327 PushDeclContext(FnBodyScope, FD); 6328 6329 // Check the validity of our function parameters 6330 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 6331 /*CheckParameterNames=*/true); 6332 6333 // Introduce our parameters into the function scope 6334 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 6335 ParmVarDecl *Param = FD->getParamDecl(p); 6336 Param->setOwningFunction(FD); 6337 6338 // If this has an identifier, add it to the scope stack. 6339 if (Param->getIdentifier() && FnBodyScope) { 6340 CheckShadow(FnBodyScope, Param); 6341 6342 PushOnScopeChains(Param, FnBodyScope); 6343 } 6344 } 6345 6346 // Checking attributes of current function definition 6347 // dllimport attribute. 6348 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 6349 if (DA && (!FD->getAttr<DLLExportAttr>())) { 6350 // dllimport attribute cannot be directly applied to definition. 6351 // Microsoft accepts dllimport for functions defined within class scope. 6352 if (!DA->isInherited() && 6353 !(LangOpts.Microsoft && FD->getLexicalDeclContext()->isRecord())) { 6354 Diag(FD->getLocation(), 6355 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 6356 << "dllimport"; 6357 FD->setInvalidDecl(); 6358 return FD; 6359 } 6360 6361 // Visual C++ appears to not think this is an issue, so only issue 6362 // a warning when Microsoft extensions are disabled. 6363 if (!LangOpts.Microsoft) { 6364 // If a symbol previously declared dllimport is later defined, the 6365 // attribute is ignored in subsequent references, and a warning is 6366 // emitted. 6367 Diag(FD->getLocation(), 6368 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 6369 << FD->getName() << "dllimport"; 6370 } 6371 } 6372 return FD; 6373} 6374 6375/// \brief Given the set of return statements within a function body, 6376/// compute the variables that are subject to the named return value 6377/// optimization. 6378/// 6379/// Each of the variables that is subject to the named return value 6380/// optimization will be marked as NRVO variables in the AST, and any 6381/// return statement that has a marked NRVO variable as its NRVO candidate can 6382/// use the named return value optimization. 6383/// 6384/// This function applies a very simplistic algorithm for NRVO: if every return 6385/// statement in the function has the same NRVO candidate, that candidate is 6386/// the NRVO variable. 6387/// 6388/// FIXME: Employ a smarter algorithm that accounts for multiple return 6389/// statements and the lifetimes of the NRVO candidates. We should be able to 6390/// find a maximal set of NRVO variables. 6391static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 6392 ReturnStmt **Returns = Scope->Returns.data(); 6393 6394 const VarDecl *NRVOCandidate = 0; 6395 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 6396 if (!Returns[I]->getNRVOCandidate()) 6397 return; 6398 6399 if (!NRVOCandidate) 6400 NRVOCandidate = Returns[I]->getNRVOCandidate(); 6401 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 6402 return; 6403 } 6404 6405 if (NRVOCandidate) 6406 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 6407} 6408 6409Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 6410 return ActOnFinishFunctionBody(D, move(BodyArg), false); 6411} 6412 6413Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 6414 bool IsInstantiation) { 6415 FunctionDecl *FD = 0; 6416 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 6417 if (FunTmpl) 6418 FD = FunTmpl->getTemplatedDecl(); 6419 else 6420 FD = dyn_cast_or_null<FunctionDecl>(dcl); 6421 6422 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 6423 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 6424 6425 if (FD) { 6426 FD->setBody(Body); 6427 if (FD->isMain()) { 6428 // C and C++ allow for main to automagically return 0. 6429 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 6430 FD->setHasImplicitReturnZero(true); 6431 WP.disableCheckFallThrough(); 6432 } 6433 6434 // MSVC permits the use of pure specifier (=0) on function definition, 6435 // defined at class scope, warn about this non standard construct. 6436 if (getLangOptions().Microsoft && FD->isPure()) 6437 Diag(FD->getLocation(), diag::warn_pure_function_definition); 6438 6439 if (!FD->isInvalidDecl()) { 6440 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 6441 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 6442 FD->getResultType(), FD); 6443 6444 // If this is a constructor, we need a vtable. 6445 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 6446 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 6447 6448 ComputeNRVO(Body, getCurFunction()); 6449 } 6450 6451 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 6452 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 6453 assert(MD == getCurMethodDecl() && "Method parsing confused"); 6454 MD->setBody(Body); 6455 if (Body) 6456 MD->setEndLoc(Body->getLocEnd()); 6457 if (!MD->isInvalidDecl()) { 6458 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 6459 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 6460 MD->getResultType(), MD); 6461 } 6462 } else { 6463 return 0; 6464 } 6465 6466 // Verify and clean out per-function state. 6467 if (Body) { 6468 // C++ constructors that have function-try-blocks can't have return 6469 // statements in the handlers of that block. (C++ [except.handle]p14) 6470 // Verify this. 6471 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 6472 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 6473 6474 // Verify that that gotos and switch cases don't jump into scopes illegally. 6475 // Verify that that gotos and switch cases don't jump into scopes illegally. 6476 if (getCurFunction()->NeedsScopeChecking() && 6477 !dcl->isInvalidDecl() && 6478 !hasAnyUnrecoverableErrorsInThisFunction()) 6479 DiagnoseInvalidJumps(Body); 6480 6481 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 6482 if (!Destructor->getParent()->isDependentType()) 6483 CheckDestructor(Destructor); 6484 6485 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 6486 Destructor->getParent()); 6487 } 6488 6489 // If any errors have occurred, clear out any temporaries that may have 6490 // been leftover. This ensures that these temporaries won't be picked up for 6491 // deletion in some later function. 6492 if (PP.getDiagnostics().hasErrorOccurred() || 6493 PP.getDiagnostics().getSuppressAllDiagnostics()) { 6494 ExprTemporaries.clear(); 6495 ExprNeedsCleanups = false; 6496 } else if (!isa<FunctionTemplateDecl>(dcl)) { 6497 // Since the body is valid, issue any analysis-based warnings that are 6498 // enabled. 6499 ActivePolicy = &WP; 6500 } 6501 6502 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 6503 assert(!ExprNeedsCleanups && "Unaccounted cleanups in function"); 6504 } 6505 6506 if (!IsInstantiation) 6507 PopDeclContext(); 6508 6509 PopFunctionOrBlockScope(ActivePolicy, dcl); 6510 6511 // If any errors have occurred, clear out any temporaries that may have 6512 // been leftover. This ensures that these temporaries won't be picked up for 6513 // deletion in some later function. 6514 if (getDiagnostics().hasErrorOccurred()) { 6515 ExprTemporaries.clear(); 6516 ExprNeedsCleanups = false; 6517 } 6518 6519 return dcl; 6520} 6521 6522/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 6523/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 6524NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 6525 IdentifierInfo &II, Scope *S) { 6526 // Before we produce a declaration for an implicitly defined 6527 // function, see whether there was a locally-scoped declaration of 6528 // this name as a function or variable. If so, use that 6529 // (non-visible) declaration, and complain about it. 6530 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 6531 = LocallyScopedExternalDecls.find(&II); 6532 if (Pos != LocallyScopedExternalDecls.end()) { 6533 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 6534 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 6535 return Pos->second; 6536 } 6537 6538 // Extension in C99. Legal in C90, but warn about it. 6539 if (II.getName().startswith("__builtin_")) 6540 Diag(Loc, diag::warn_builtin_unknown) << &II; 6541 else if (getLangOptions().C99) 6542 Diag(Loc, diag::ext_implicit_function_decl) << &II; 6543 else 6544 Diag(Loc, diag::warn_implicit_function_decl) << &II; 6545 6546 // Set a Declarator for the implicit definition: int foo(); 6547 const char *Dummy; 6548 AttributeFactory attrFactory; 6549 DeclSpec DS(attrFactory); 6550 unsigned DiagID; 6551 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 6552 (void)Error; // Silence warning. 6553 assert(!Error && "Error setting up implicit decl!"); 6554 Declarator D(DS, Declarator::BlockContext); 6555 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 6556 0, 0, true, SourceLocation(), 6557 EST_None, SourceLocation(), 6558 0, 0, 0, 0, Loc, Loc, D), 6559 DS.getAttributes(), 6560 SourceLocation()); 6561 D.SetIdentifier(&II, Loc); 6562 6563 // Insert this function into translation-unit scope. 6564 6565 DeclContext *PrevDC = CurContext; 6566 CurContext = Context.getTranslationUnitDecl(); 6567 6568 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 6569 FD->setImplicit(); 6570 6571 CurContext = PrevDC; 6572 6573 AddKnownFunctionAttributes(FD); 6574 6575 return FD; 6576} 6577 6578/// \brief Adds any function attributes that we know a priori based on 6579/// the declaration of this function. 6580/// 6581/// These attributes can apply both to implicitly-declared builtins 6582/// (like __builtin___printf_chk) or to library-declared functions 6583/// like NSLog or printf. 6584/// 6585/// We need to check for duplicate attributes both here and where user-written 6586/// attributes are applied to declarations. 6587void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 6588 if (FD->isInvalidDecl()) 6589 return; 6590 6591 // If this is a built-in function, map its builtin attributes to 6592 // actual attributes. 6593 if (unsigned BuiltinID = FD->getBuiltinID()) { 6594 // Handle printf-formatting attributes. 6595 unsigned FormatIdx; 6596 bool HasVAListArg; 6597 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 6598 if (!FD->getAttr<FormatAttr>()) 6599 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6600 "printf", FormatIdx+1, 6601 HasVAListArg ? 0 : FormatIdx+2)); 6602 } 6603 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 6604 HasVAListArg)) { 6605 if (!FD->getAttr<FormatAttr>()) 6606 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6607 "scanf", FormatIdx+1, 6608 HasVAListArg ? 0 : FormatIdx+2)); 6609 } 6610 6611 // Mark const if we don't care about errno and that is the only 6612 // thing preventing the function from being const. This allows 6613 // IRgen to use LLVM intrinsics for such functions. 6614 if (!getLangOptions().MathErrno && 6615 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 6616 if (!FD->getAttr<ConstAttr>()) 6617 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6618 } 6619 6620 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->getAttr<NoThrowAttr>()) 6621 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 6622 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->getAttr<ConstAttr>()) 6623 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6624 } 6625 6626 IdentifierInfo *Name = FD->getIdentifier(); 6627 if (!Name) 6628 return; 6629 if ((!getLangOptions().CPlusPlus && 6630 FD->getDeclContext()->isTranslationUnit()) || 6631 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 6632 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 6633 LinkageSpecDecl::lang_c)) { 6634 // Okay: this could be a libc/libm/Objective-C function we know 6635 // about. 6636 } else 6637 return; 6638 6639 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 6640 // FIXME: NSLog and NSLogv should be target specific 6641 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 6642 // FIXME: We known better than our headers. 6643 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 6644 } else 6645 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6646 "printf", 1, 6647 Name->isStr("NSLogv") ? 0 : 2)); 6648 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 6649 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 6650 // target-specific builtins, perhaps? 6651 if (!FD->getAttr<FormatAttr>()) 6652 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6653 "printf", 2, 6654 Name->isStr("vasprintf") ? 0 : 3)); 6655 } 6656} 6657 6658TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 6659 TypeSourceInfo *TInfo) { 6660 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 6661 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 6662 6663 if (!TInfo) { 6664 assert(D.isInvalidType() && "no declarator info for valid type"); 6665 TInfo = Context.getTrivialTypeSourceInfo(T); 6666 } 6667 6668 // Scope manipulation handled by caller. 6669 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 6670 D.getSourceRange().getBegin(), 6671 D.getIdentifierLoc(), 6672 D.getIdentifier(), 6673 TInfo); 6674 6675 // Bail out immediately if we have an invalid declaration. 6676 if (D.isInvalidType()) { 6677 NewTD->setInvalidDecl(); 6678 return NewTD; 6679 } 6680 6681 // C++ [dcl.typedef]p8: 6682 // If the typedef declaration defines an unnamed class (or 6683 // enum), the first typedef-name declared by the declaration 6684 // to be that class type (or enum type) is used to denote the 6685 // class type (or enum type) for linkage purposes only. 6686 // We need to check whether the type was declared in the declaration. 6687 switch (D.getDeclSpec().getTypeSpecType()) { 6688 case TST_enum: 6689 case TST_struct: 6690 case TST_union: 6691 case TST_class: { 6692 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 6693 6694 // Do nothing if the tag is not anonymous or already has an 6695 // associated typedef (from an earlier typedef in this decl group). 6696 if (tagFromDeclSpec->getIdentifier()) break; 6697 if (tagFromDeclSpec->getTypedefNameForAnonDecl()) break; 6698 6699 // A well-formed anonymous tag must always be a TUK_Definition. 6700 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 6701 6702 // The type must match the tag exactly; no qualifiers allowed. 6703 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 6704 break; 6705 6706 // Otherwise, set this is the anon-decl typedef for the tag. 6707 tagFromDeclSpec->setTypedefNameForAnonDecl(NewTD); 6708 break; 6709 } 6710 6711 default: 6712 break; 6713 } 6714 6715 return NewTD; 6716} 6717 6718 6719/// \brief Determine whether a tag with a given kind is acceptable 6720/// as a redeclaration of the given tag declaration. 6721/// 6722/// \returns true if the new tag kind is acceptable, false otherwise. 6723bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 6724 TagTypeKind NewTag, bool isDefinition, 6725 SourceLocation NewTagLoc, 6726 const IdentifierInfo &Name) { 6727 // C++ [dcl.type.elab]p3: 6728 // The class-key or enum keyword present in the 6729 // elaborated-type-specifier shall agree in kind with the 6730 // declaration to which the name in the elaborated-type-specifier 6731 // refers. This rule also applies to the form of 6732 // elaborated-type-specifier that declares a class-name or 6733 // friend class since it can be construed as referring to the 6734 // definition of the class. Thus, in any 6735 // elaborated-type-specifier, the enum keyword shall be used to 6736 // refer to an enumeration (7.2), the union class-key shall be 6737 // used to refer to a union (clause 9), and either the class or 6738 // struct class-key shall be used to refer to a class (clause 9) 6739 // declared using the class or struct class-key. 6740 TagTypeKind OldTag = Previous->getTagKind(); 6741 if (!isDefinition || (NewTag != TTK_Class && NewTag != TTK_Struct)) 6742 if (OldTag == NewTag) 6743 return true; 6744 6745 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 6746 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 6747 // Warn about the struct/class tag mismatch. 6748 bool isTemplate = false; 6749 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 6750 isTemplate = Record->getDescribedClassTemplate(); 6751 6752 if (!ActiveTemplateInstantiations.empty()) { 6753 // In a template instantiation, do not offer fix-its for tag mismatches 6754 // since they usually mess up the template instead of fixing the problem. 6755 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6756 << (NewTag == TTK_Class) << isTemplate << &Name; 6757 return true; 6758 } 6759 6760 if (isDefinition) { 6761 // On definitions, check previous tags and issue a fix-it for each 6762 // one that doesn't match the current tag. 6763 if (Previous->getDefinition()) { 6764 // Don't suggest fix-its for redefinitions. 6765 return true; 6766 } 6767 6768 bool previousMismatch = false; 6769 for (TagDecl::redecl_iterator I(Previous->redecls_begin()), 6770 E(Previous->redecls_end()); I != E; ++I) { 6771 if (I->getTagKind() != NewTag) { 6772 if (!previousMismatch) { 6773 previousMismatch = true; 6774 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch) 6775 << (NewTag == TTK_Class) << isTemplate << &Name; 6776 } 6777 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion) 6778 << (NewTag == TTK_Class) 6779 << FixItHint::CreateReplacement(I->getInnerLocStart(), 6780 NewTag == TTK_Class? 6781 "class" : "struct"); 6782 } 6783 } 6784 return true; 6785 } 6786 6787 // Check for a previous definition. If current tag and definition 6788 // are same type, do nothing. If no definition, but disagree with 6789 // with previous tag type, give a warning, but no fix-it. 6790 const TagDecl *Redecl = Previous->getDefinition() ? 6791 Previous->getDefinition() : Previous; 6792 if (Redecl->getTagKind() == NewTag) { 6793 return true; 6794 } 6795 6796 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6797 << (NewTag == TTK_Class) 6798 << isTemplate << &Name; 6799 Diag(Redecl->getLocation(), diag::note_previous_use); 6800 6801 // If there is a previous defintion, suggest a fix-it. 6802 if (Previous->getDefinition()) { 6803 Diag(NewTagLoc, diag::note_struct_class_suggestion) 6804 << (Redecl->getTagKind() == TTK_Class) 6805 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 6806 Redecl->getTagKind() == TTK_Class? "class" : "struct"); 6807 } 6808 6809 return true; 6810 } 6811 return false; 6812} 6813 6814/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 6815/// former case, Name will be non-null. In the later case, Name will be null. 6816/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 6817/// reference/declaration/definition of a tag. 6818Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 6819 SourceLocation KWLoc, CXXScopeSpec &SS, 6820 IdentifierInfo *Name, SourceLocation NameLoc, 6821 AttributeList *Attr, AccessSpecifier AS, 6822 MultiTemplateParamsArg TemplateParameterLists, 6823 bool &OwnedDecl, bool &IsDependent, 6824 bool ScopedEnum, bool ScopedEnumUsesClassTag, 6825 TypeResult UnderlyingType) { 6826 // If this is not a definition, it must have a name. 6827 assert((Name != 0 || TUK == TUK_Definition) && 6828 "Nameless record must be a definition!"); 6829 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 6830 6831 OwnedDecl = false; 6832 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 6833 6834 // FIXME: Check explicit specializations more carefully. 6835 bool isExplicitSpecialization = false; 6836 bool Invalid = false; 6837 6838 // We only need to do this matching if we have template parameters 6839 // or a scope specifier, which also conveniently avoids this work 6840 // for non-C++ cases. 6841 if (TemplateParameterLists.size() > 0 || 6842 (SS.isNotEmpty() && TUK != TUK_Reference)) { 6843 if (TemplateParameterList *TemplateParams 6844 = MatchTemplateParametersToScopeSpecifier(KWLoc, NameLoc, SS, 6845 TemplateParameterLists.get(), 6846 TemplateParameterLists.size(), 6847 TUK == TUK_Friend, 6848 isExplicitSpecialization, 6849 Invalid)) { 6850 if (TemplateParams->size() > 0) { 6851 // This is a declaration or definition of a class template (which may 6852 // be a member of another template). 6853 6854 if (Invalid) 6855 return 0; 6856 6857 OwnedDecl = false; 6858 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6859 SS, Name, NameLoc, Attr, 6860 TemplateParams, AS, 6861 TemplateParameterLists.size() - 1, 6862 (TemplateParameterList**) TemplateParameterLists.release()); 6863 return Result.get(); 6864 } else { 6865 // The "template<>" header is extraneous. 6866 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6867 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6868 isExplicitSpecialization = true; 6869 } 6870 } 6871 } 6872 6873 // Figure out the underlying type if this a enum declaration. We need to do 6874 // this early, because it's needed to detect if this is an incompatible 6875 // redeclaration. 6876 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6877 6878 if (Kind == TTK_Enum) { 6879 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6880 // No underlying type explicitly specified, or we failed to parse the 6881 // type, default to int. 6882 EnumUnderlying = Context.IntTy.getTypePtr(); 6883 else if (UnderlyingType.get()) { 6884 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6885 // integral type; any cv-qualification is ignored. 6886 TypeSourceInfo *TI = 0; 6887 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6888 EnumUnderlying = TI; 6889 6890 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6891 6892 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6893 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6894 << T; 6895 // Recover by falling back to int. 6896 EnumUnderlying = Context.IntTy.getTypePtr(); 6897 } 6898 6899 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6900 UPPC_FixedUnderlyingType)) 6901 EnumUnderlying = Context.IntTy.getTypePtr(); 6902 6903 } else if (getLangOptions().Microsoft) 6904 // Microsoft enums are always of int type. 6905 EnumUnderlying = Context.IntTy.getTypePtr(); 6906 } 6907 6908 DeclContext *SearchDC = CurContext; 6909 DeclContext *DC = CurContext; 6910 bool isStdBadAlloc = false; 6911 6912 RedeclarationKind Redecl = ForRedeclaration; 6913 if (TUK == TUK_Friend || TUK == TUK_Reference) 6914 Redecl = NotForRedeclaration; 6915 6916 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6917 6918 if (Name && SS.isNotEmpty()) { 6919 // We have a nested-name tag ('struct foo::bar'). 6920 6921 // Check for invalid 'foo::'. 6922 if (SS.isInvalid()) { 6923 Name = 0; 6924 goto CreateNewDecl; 6925 } 6926 6927 // If this is a friend or a reference to a class in a dependent 6928 // context, don't try to make a decl for it. 6929 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6930 DC = computeDeclContext(SS, false); 6931 if (!DC) { 6932 IsDependent = true; 6933 return 0; 6934 } 6935 } else { 6936 DC = computeDeclContext(SS, true); 6937 if (!DC) { 6938 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6939 << SS.getRange(); 6940 return 0; 6941 } 6942 } 6943 6944 if (RequireCompleteDeclContext(SS, DC)) 6945 return 0; 6946 6947 SearchDC = DC; 6948 // Look-up name inside 'foo::'. 6949 LookupQualifiedName(Previous, DC); 6950 6951 if (Previous.isAmbiguous()) 6952 return 0; 6953 6954 if (Previous.empty()) { 6955 // Name lookup did not find anything. However, if the 6956 // nested-name-specifier refers to the current instantiation, 6957 // and that current instantiation has any dependent base 6958 // classes, we might find something at instantiation time: treat 6959 // this as a dependent elaborated-type-specifier. 6960 // But this only makes any sense for reference-like lookups. 6961 if (Previous.wasNotFoundInCurrentInstantiation() && 6962 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6963 IsDependent = true; 6964 return 0; 6965 } 6966 6967 // A tag 'foo::bar' must already exist. 6968 Diag(NameLoc, diag::err_not_tag_in_scope) 6969 << Kind << Name << DC << SS.getRange(); 6970 Name = 0; 6971 Invalid = true; 6972 goto CreateNewDecl; 6973 } 6974 } else if (Name) { 6975 // If this is a named struct, check to see if there was a previous forward 6976 // declaration or definition. 6977 // FIXME: We're looking into outer scopes here, even when we 6978 // shouldn't be. Doing so can result in ambiguities that we 6979 // shouldn't be diagnosing. 6980 LookupName(Previous, S); 6981 6982 if (Previous.isAmbiguous() && 6983 (TUK == TUK_Definition || TUK == TUK_Declaration)) { 6984 LookupResult::Filter F = Previous.makeFilter(); 6985 while (F.hasNext()) { 6986 NamedDecl *ND = F.next(); 6987 if (ND->getDeclContext()->getRedeclContext() != SearchDC) 6988 F.erase(); 6989 } 6990 F.done(); 6991 } 6992 6993 // Note: there used to be some attempt at recovery here. 6994 if (Previous.isAmbiguous()) 6995 return 0; 6996 6997 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6998 // FIXME: This makes sure that we ignore the contexts associated 6999 // with C structs, unions, and enums when looking for a matching 7000 // tag declaration or definition. See the similar lookup tweak 7001 // in Sema::LookupName; is there a better way to deal with this? 7002 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 7003 SearchDC = SearchDC->getParent(); 7004 } 7005 } else if (S->isFunctionPrototypeScope()) { 7006 // If this is an enum declaration in function prototype scope, set its 7007 // initial context to the translation unit. 7008 SearchDC = Context.getTranslationUnitDecl(); 7009 } 7010 7011 if (Previous.isSingleResult() && 7012 Previous.getFoundDecl()->isTemplateParameter()) { 7013 // Maybe we will complain about the shadowed template parameter. 7014 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 7015 // Just pretend that we didn't see the previous declaration. 7016 Previous.clear(); 7017 } 7018 7019 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 7020 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 7021 // This is a declaration of or a reference to "std::bad_alloc". 7022 isStdBadAlloc = true; 7023 7024 if (Previous.empty() && StdBadAlloc) { 7025 // std::bad_alloc has been implicitly declared (but made invisible to 7026 // name lookup). Fill in this implicit declaration as the previous 7027 // declaration, so that the declarations get chained appropriately. 7028 Previous.addDecl(getStdBadAlloc()); 7029 } 7030 } 7031 7032 // If we didn't find a previous declaration, and this is a reference 7033 // (or friend reference), move to the correct scope. In C++, we 7034 // also need to do a redeclaration lookup there, just in case 7035 // there's a shadow friend decl. 7036 if (Name && Previous.empty() && 7037 (TUK == TUK_Reference || TUK == TUK_Friend)) { 7038 if (Invalid) goto CreateNewDecl; 7039 assert(SS.isEmpty()); 7040 7041 if (TUK == TUK_Reference) { 7042 // C++ [basic.scope.pdecl]p5: 7043 // -- for an elaborated-type-specifier of the form 7044 // 7045 // class-key identifier 7046 // 7047 // if the elaborated-type-specifier is used in the 7048 // decl-specifier-seq or parameter-declaration-clause of a 7049 // function defined in namespace scope, the identifier is 7050 // declared as a class-name in the namespace that contains 7051 // the declaration; otherwise, except as a friend 7052 // declaration, the identifier is declared in the smallest 7053 // non-class, non-function-prototype scope that contains the 7054 // declaration. 7055 // 7056 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 7057 // C structs and unions. 7058 // 7059 // It is an error in C++ to declare (rather than define) an enum 7060 // type, including via an elaborated type specifier. We'll 7061 // diagnose that later; for now, declare the enum in the same 7062 // scope as we would have picked for any other tag type. 7063 // 7064 // GNU C also supports this behavior as part of its incomplete 7065 // enum types extension, while GNU C++ does not. 7066 // 7067 // Find the context where we'll be declaring the tag. 7068 // FIXME: We would like to maintain the current DeclContext as the 7069 // lexical context, 7070 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 7071 SearchDC = SearchDC->getParent(); 7072 7073 // Find the scope where we'll be declaring the tag. 7074 while (S->isClassScope() || 7075 (getLangOptions().CPlusPlus && 7076 S->isFunctionPrototypeScope()) || 7077 ((S->getFlags() & Scope::DeclScope) == 0) || 7078 (S->getEntity() && 7079 ((DeclContext *)S->getEntity())->isTransparentContext())) 7080 S = S->getParent(); 7081 } else { 7082 assert(TUK == TUK_Friend); 7083 // C++ [namespace.memdef]p3: 7084 // If a friend declaration in a non-local class first declares a 7085 // class or function, the friend class or function is a member of 7086 // the innermost enclosing namespace. 7087 SearchDC = SearchDC->getEnclosingNamespaceContext(); 7088 } 7089 7090 // In C++, we need to do a redeclaration lookup to properly 7091 // diagnose some problems. 7092 if (getLangOptions().CPlusPlus) { 7093 Previous.setRedeclarationKind(ForRedeclaration); 7094 LookupQualifiedName(Previous, SearchDC); 7095 } 7096 } 7097 7098 if (!Previous.empty()) { 7099 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 7100 7101 // It's okay to have a tag decl in the same scope as a typedef 7102 // which hides a tag decl in the same scope. Finding this 7103 // insanity with a redeclaration lookup can only actually happen 7104 // in C++. 7105 // 7106 // This is also okay for elaborated-type-specifiers, which is 7107 // technically forbidden by the current standard but which is 7108 // okay according to the likely resolution of an open issue; 7109 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 7110 if (getLangOptions().CPlusPlus) { 7111 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) { 7112 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 7113 TagDecl *Tag = TT->getDecl(); 7114 if (Tag->getDeclName() == Name && 7115 Tag->getDeclContext()->getRedeclContext() 7116 ->Equals(TD->getDeclContext()->getRedeclContext())) { 7117 PrevDecl = Tag; 7118 Previous.clear(); 7119 Previous.addDecl(Tag); 7120 Previous.resolveKind(); 7121 } 7122 } 7123 } 7124 } 7125 7126 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 7127 // If this is a use of a previous tag, or if the tag is already declared 7128 // in the same scope (so that the definition/declaration completes or 7129 // rementions the tag), reuse the decl. 7130 if (TUK == TUK_Reference || TUK == TUK_Friend || 7131 isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { 7132 // Make sure that this wasn't declared as an enum and now used as a 7133 // struct or something similar. 7134 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, 7135 TUK == TUK_Definition, KWLoc, 7136 *Name)) { 7137 bool SafeToContinue 7138 = (PrevTagDecl->getTagKind() != TTK_Enum && 7139 Kind != TTK_Enum); 7140 if (SafeToContinue) 7141 Diag(KWLoc, diag::err_use_with_wrong_tag) 7142 << Name 7143 << FixItHint::CreateReplacement(SourceRange(KWLoc), 7144 PrevTagDecl->getKindName()); 7145 else 7146 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 7147 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 7148 7149 if (SafeToContinue) 7150 Kind = PrevTagDecl->getTagKind(); 7151 else { 7152 // Recover by making this an anonymous redefinition. 7153 Name = 0; 7154 Previous.clear(); 7155 Invalid = true; 7156 } 7157 } 7158 7159 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 7160 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 7161 7162 // All conflicts with previous declarations are recovered by 7163 // returning the previous declaration. 7164 if (ScopedEnum != PrevEnum->isScoped()) { 7165 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 7166 << PrevEnum->isScoped(); 7167 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 7168 return PrevTagDecl; 7169 } 7170 else if (EnumUnderlying && PrevEnum->isFixed()) { 7171 QualType T; 7172 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 7173 T = TI->getType(); 7174 else 7175 T = QualType(EnumUnderlying.get<const Type*>(), 0); 7176 7177 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 7178 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 7179 diag::err_enum_redeclare_type_mismatch) 7180 << T 7181 << PrevEnum->getIntegerType(); 7182 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 7183 return PrevTagDecl; 7184 } 7185 } 7186 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 7187 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 7188 << PrevEnum->isFixed(); 7189 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 7190 return PrevTagDecl; 7191 } 7192 } 7193 7194 if (!Invalid) { 7195 // If this is a use, just return the declaration we found. 7196 7197 // FIXME: In the future, return a variant or some other clue 7198 // for the consumer of this Decl to know it doesn't own it. 7199 // For our current ASTs this shouldn't be a problem, but will 7200 // need to be changed with DeclGroups. 7201 if ((TUK == TUK_Reference && (!PrevTagDecl->getFriendObjectKind() || 7202 getLangOptions().Microsoft)) || TUK == TUK_Friend) 7203 return PrevTagDecl; 7204 7205 // Diagnose attempts to redefine a tag. 7206 if (TUK == TUK_Definition) { 7207 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 7208 // If we're defining a specialization and the previous definition 7209 // is from an implicit instantiation, don't emit an error 7210 // here; we'll catch this in the general case below. 7211 if (!isExplicitSpecialization || 7212 !isa<CXXRecordDecl>(Def) || 7213 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 7214 == TSK_ExplicitSpecialization) { 7215 Diag(NameLoc, diag::err_redefinition) << Name; 7216 Diag(Def->getLocation(), diag::note_previous_definition); 7217 // If this is a redefinition, recover by making this 7218 // struct be anonymous, which will make any later 7219 // references get the previous definition. 7220 Name = 0; 7221 Previous.clear(); 7222 Invalid = true; 7223 } 7224 } else { 7225 // If the type is currently being defined, complain 7226 // about a nested redefinition. 7227 const TagType *Tag 7228 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 7229 if (Tag->isBeingDefined()) { 7230 Diag(NameLoc, diag::err_nested_redefinition) << Name; 7231 Diag(PrevTagDecl->getLocation(), 7232 diag::note_previous_definition); 7233 Name = 0; 7234 Previous.clear(); 7235 Invalid = true; 7236 } 7237 } 7238 7239 // Okay, this is definition of a previously declared or referenced 7240 // tag PrevDecl. We're going to create a new Decl for it. 7241 } 7242 } 7243 // If we get here we have (another) forward declaration or we 7244 // have a definition. Just create a new decl. 7245 7246 } else { 7247 // If we get here, this is a definition of a new tag type in a nested 7248 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 7249 // new decl/type. We set PrevDecl to NULL so that the entities 7250 // have distinct types. 7251 Previous.clear(); 7252 } 7253 // If we get here, we're going to create a new Decl. If PrevDecl 7254 // is non-NULL, it's a definition of the tag declared by 7255 // PrevDecl. If it's NULL, we have a new definition. 7256 7257 7258 // Otherwise, PrevDecl is not a tag, but was found with tag 7259 // lookup. This is only actually possible in C++, where a few 7260 // things like templates still live in the tag namespace. 7261 } else { 7262 assert(getLangOptions().CPlusPlus); 7263 7264 // Use a better diagnostic if an elaborated-type-specifier 7265 // found the wrong kind of type on the first 7266 // (non-redeclaration) lookup. 7267 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 7268 !Previous.isForRedeclaration()) { 7269 unsigned Kind = 0; 7270 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 7271 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; 7272 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; 7273 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 7274 Diag(PrevDecl->getLocation(), diag::note_declared_at); 7275 Invalid = true; 7276 7277 // Otherwise, only diagnose if the declaration is in scope. 7278 } else if (!isDeclInScope(PrevDecl, SearchDC, S, 7279 isExplicitSpecialization)) { 7280 // do nothing 7281 7282 // Diagnose implicit declarations introduced by elaborated types. 7283 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 7284 unsigned Kind = 0; 7285 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 7286 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; 7287 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; 7288 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 7289 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 7290 Invalid = true; 7291 7292 // Otherwise it's a declaration. Call out a particularly common 7293 // case here. 7294 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) { 7295 unsigned Kind = 0; 7296 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1; 7297 Diag(NameLoc, diag::err_tag_definition_of_typedef) 7298 << Name << Kind << TND->getUnderlyingType(); 7299 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 7300 Invalid = true; 7301 7302 // Otherwise, diagnose. 7303 } else { 7304 // The tag name clashes with something else in the target scope, 7305 // issue an error and recover by making this tag be anonymous. 7306 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 7307 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7308 Name = 0; 7309 Invalid = true; 7310 } 7311 7312 // The existing declaration isn't relevant to us; we're in a 7313 // new scope, so clear out the previous declaration. 7314 Previous.clear(); 7315 } 7316 } 7317 7318CreateNewDecl: 7319 7320 TagDecl *PrevDecl = 0; 7321 if (Previous.isSingleResult()) 7322 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 7323 7324 // If there is an identifier, use the location of the identifier as the 7325 // location of the decl, otherwise use the location of the struct/union 7326 // keyword. 7327 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 7328 7329 // Otherwise, create a new declaration. If there is a previous 7330 // declaration of the same entity, the two will be linked via 7331 // PrevDecl. 7332 TagDecl *New; 7333 7334 bool IsForwardReference = false; 7335 if (Kind == TTK_Enum) { 7336 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 7337 // enum X { A, B, C } D; D should chain to X. 7338 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, 7339 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 7340 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 7341 // If this is an undefined enum, warn. 7342 if (TUK != TUK_Definition && !Invalid) { 7343 TagDecl *Def; 7344 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 7345 // C++0x: 7.2p2: opaque-enum-declaration. 7346 // Conflicts are diagnosed above. Do nothing. 7347 } 7348 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 7349 Diag(Loc, diag::ext_forward_ref_enum_def) 7350 << New; 7351 Diag(Def->getLocation(), diag::note_previous_definition); 7352 } else { 7353 unsigned DiagID = diag::ext_forward_ref_enum; 7354 if (getLangOptions().Microsoft) 7355 DiagID = diag::ext_ms_forward_ref_enum; 7356 else if (getLangOptions().CPlusPlus) 7357 DiagID = diag::err_forward_ref_enum; 7358 Diag(Loc, DiagID); 7359 7360 // If this is a forward-declared reference to an enumeration, make a 7361 // note of it; we won't actually be introducing the declaration into 7362 // the declaration context. 7363 if (TUK == TUK_Reference) 7364 IsForwardReference = true; 7365 } 7366 } 7367 7368 if (EnumUnderlying) { 7369 EnumDecl *ED = cast<EnumDecl>(New); 7370 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 7371 ED->setIntegerTypeSourceInfo(TI); 7372 else 7373 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 7374 ED->setPromotionType(ED->getIntegerType()); 7375 } 7376 7377 } else { 7378 // struct/union/class 7379 7380 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 7381 // struct X { int A; } D; D should chain to X. 7382 if (getLangOptions().CPlusPlus) { 7383 // FIXME: Look for a way to use RecordDecl for simple structs. 7384 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 7385 cast_or_null<CXXRecordDecl>(PrevDecl)); 7386 7387 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 7388 StdBadAlloc = cast<CXXRecordDecl>(New); 7389 } else 7390 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 7391 cast_or_null<RecordDecl>(PrevDecl)); 7392 } 7393 7394 // Maybe add qualifier info. 7395 if (SS.isNotEmpty()) { 7396 if (SS.isSet()) { 7397 New->setQualifierInfo(SS.getWithLocInContext(Context)); 7398 if (TemplateParameterLists.size() > 0) { 7399 New->setTemplateParameterListsInfo(Context, 7400 TemplateParameterLists.size(), 7401 (TemplateParameterList**) TemplateParameterLists.release()); 7402 } 7403 } 7404 else 7405 Invalid = true; 7406 } 7407 7408 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 7409 // Add alignment attributes if necessary; these attributes are checked when 7410 // the ASTContext lays out the structure. 7411 // 7412 // It is important for implementing the correct semantics that this 7413 // happen here (in act on tag decl). The #pragma pack stack is 7414 // maintained as a result of parser callbacks which can occur at 7415 // many points during the parsing of a struct declaration (because 7416 // the #pragma tokens are effectively skipped over during the 7417 // parsing of the struct). 7418 AddAlignmentAttributesForRecord(RD); 7419 7420 AddMsStructLayoutForRecord(RD); 7421 } 7422 7423 // If this is a specialization of a member class (of a class template), 7424 // check the specialization. 7425 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 7426 Invalid = true; 7427 7428 if (Invalid) 7429 New->setInvalidDecl(); 7430 7431 if (Attr) 7432 ProcessDeclAttributeList(S, New, Attr); 7433 7434 // If we're declaring or defining a tag in function prototype scope 7435 // in C, note that this type can only be used within the function. 7436 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 7437 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 7438 7439 // Set the lexical context. If the tag has a C++ scope specifier, the 7440 // lexical context will be different from the semantic context. 7441 New->setLexicalDeclContext(CurContext); 7442 7443 // Mark this as a friend decl if applicable. 7444 // In Microsoft mode, a friend declaration also acts as a forward 7445 // declaration so we always pass true to setObjectOfFriendDecl to make 7446 // the tag name visible. 7447 if (TUK == TUK_Friend) 7448 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty() || 7449 getLangOptions().Microsoft); 7450 7451 // Set the access specifier. 7452 if (!Invalid && SearchDC->isRecord()) 7453 SetMemberAccessSpecifier(New, PrevDecl, AS); 7454 7455 if (TUK == TUK_Definition) 7456 New->startDefinition(); 7457 7458 // If this has an identifier, add it to the scope stack. 7459 if (TUK == TUK_Friend) { 7460 // We might be replacing an existing declaration in the lookup tables; 7461 // if so, borrow its access specifier. 7462 if (PrevDecl) 7463 New->setAccess(PrevDecl->getAccess()); 7464 7465 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 7466 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 7467 if (Name) // can be null along some error paths 7468 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 7469 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 7470 } else if (Name) { 7471 S = getNonFieldDeclScope(S); 7472 PushOnScopeChains(New, S, !IsForwardReference); 7473 if (IsForwardReference) 7474 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 7475 7476 } else { 7477 CurContext->addDecl(New); 7478 } 7479 7480 // If this is the C FILE type, notify the AST context. 7481 if (IdentifierInfo *II = New->getIdentifier()) 7482 if (!New->isInvalidDecl() && 7483 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 7484 II->isStr("FILE")) 7485 Context.setFILEDecl(New); 7486 7487 OwnedDecl = true; 7488 return New; 7489} 7490 7491void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 7492 AdjustDeclIfTemplate(TagD); 7493 TagDecl *Tag = cast<TagDecl>(TagD); 7494 7495 // Enter the tag context. 7496 PushDeclContext(S, Tag); 7497} 7498 7499void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 7500 SourceLocation FinalLoc, 7501 SourceLocation LBraceLoc) { 7502 AdjustDeclIfTemplate(TagD); 7503 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 7504 7505 FieldCollector->StartClass(); 7506 7507 if (!Record->getIdentifier()) 7508 return; 7509 7510 if (FinalLoc.isValid()) 7511 Record->addAttr(new (Context) FinalAttr(FinalLoc, Context)); 7512 7513 // C++ [class]p2: 7514 // [...] The class-name is also inserted into the scope of the 7515 // class itself; this is known as the injected-class-name. For 7516 // purposes of access checking, the injected-class-name is treated 7517 // as if it were a public member name. 7518 CXXRecordDecl *InjectedClassName 7519 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, 7520 Record->getLocStart(), Record->getLocation(), 7521 Record->getIdentifier(), 7522 /*PrevDecl=*/0, 7523 /*DelayTypeCreation=*/true); 7524 Context.getTypeDeclType(InjectedClassName, Record); 7525 InjectedClassName->setImplicit(); 7526 InjectedClassName->setAccess(AS_public); 7527 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 7528 InjectedClassName->setDescribedClassTemplate(Template); 7529 PushOnScopeChains(InjectedClassName, S); 7530 assert(InjectedClassName->isInjectedClassName() && 7531 "Broken injected-class-name"); 7532} 7533 7534void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 7535 SourceLocation RBraceLoc) { 7536 AdjustDeclIfTemplate(TagD); 7537 TagDecl *Tag = cast<TagDecl>(TagD); 7538 Tag->setRBraceLoc(RBraceLoc); 7539 7540 if (isa<CXXRecordDecl>(Tag)) 7541 FieldCollector->FinishClass(); 7542 7543 // Exit this scope of this tag's definition. 7544 PopDeclContext(); 7545 7546 // Notify the consumer that we've defined a tag. 7547 Consumer.HandleTagDeclDefinition(Tag); 7548} 7549 7550void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 7551 AdjustDeclIfTemplate(TagD); 7552 TagDecl *Tag = cast<TagDecl>(TagD); 7553 Tag->setInvalidDecl(); 7554 7555 // We're undoing ActOnTagStartDefinition here, not 7556 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 7557 // the FieldCollector. 7558 7559 PopDeclContext(); 7560} 7561 7562// Note that FieldName may be null for anonymous bitfields. 7563bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 7564 QualType FieldTy, const Expr *BitWidth, 7565 bool *ZeroWidth) { 7566 // Default to true; that shouldn't confuse checks for emptiness 7567 if (ZeroWidth) 7568 *ZeroWidth = true; 7569 7570 // C99 6.7.2.1p4 - verify the field type. 7571 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 7572 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 7573 // Handle incomplete types with specific error. 7574 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 7575 return true; 7576 if (FieldName) 7577 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 7578 << FieldName << FieldTy << BitWidth->getSourceRange(); 7579 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 7580 << FieldTy << BitWidth->getSourceRange(); 7581 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 7582 UPPC_BitFieldWidth)) 7583 return true; 7584 7585 // If the bit-width is type- or value-dependent, don't try to check 7586 // it now. 7587 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 7588 return false; 7589 7590 llvm::APSInt Value; 7591 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 7592 return true; 7593 7594 if (Value != 0 && ZeroWidth) 7595 *ZeroWidth = false; 7596 7597 // Zero-width bitfield is ok for anonymous field. 7598 if (Value == 0 && FieldName) 7599 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 7600 7601 if (Value.isSigned() && Value.isNegative()) { 7602 if (FieldName) 7603 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 7604 << FieldName << Value.toString(10); 7605 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 7606 << Value.toString(10); 7607 } 7608 7609 if (!FieldTy->isDependentType()) { 7610 uint64_t TypeSize = Context.getTypeSize(FieldTy); 7611 if (Value.getZExtValue() > TypeSize) { 7612 if (!getLangOptions().CPlusPlus) { 7613 if (FieldName) 7614 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 7615 << FieldName << (unsigned)Value.getZExtValue() 7616 << (unsigned)TypeSize; 7617 7618 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 7619 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 7620 } 7621 7622 if (FieldName) 7623 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 7624 << FieldName << (unsigned)Value.getZExtValue() 7625 << (unsigned)TypeSize; 7626 else 7627 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 7628 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 7629 } 7630 } 7631 7632 return false; 7633} 7634 7635/// ActOnField - Each field of a C struct/union is passed into this in order 7636/// to create a FieldDecl object for it. 7637Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart, 7638 Declarator &D, ExprTy *BitfieldWidth) { 7639 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 7640 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 7641 /*HasInit=*/false, AS_public); 7642 return Res; 7643} 7644 7645/// HandleField - Analyze a field of a C struct or a C++ data member. 7646/// 7647FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 7648 SourceLocation DeclStart, 7649 Declarator &D, Expr *BitWidth, bool HasInit, 7650 AccessSpecifier AS) { 7651 IdentifierInfo *II = D.getIdentifier(); 7652 SourceLocation Loc = DeclStart; 7653 if (II) Loc = D.getIdentifierLoc(); 7654 7655 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7656 QualType T = TInfo->getType(); 7657 if (getLangOptions().CPlusPlus) { 7658 CheckExtraCXXDefaultArguments(D); 7659 7660 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 7661 UPPC_DataMemberType)) { 7662 D.setInvalidType(); 7663 T = Context.IntTy; 7664 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 7665 } 7666 } 7667 7668 DiagnoseFunctionSpecifiers(D); 7669 7670 if (D.getDeclSpec().isThreadSpecified()) 7671 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 7672 7673 // Check to see if this name was declared as a member previously 7674 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 7675 LookupName(Previous, S); 7676 assert((Previous.empty() || Previous.isOverloadedResult() || 7677 Previous.isSingleResult()) 7678 && "Lookup of member name should be either overloaded, single or null"); 7679 7680 // If the name is overloaded then get any declaration else get the single result 7681 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 7682 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 7683 7684 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7685 // Maybe we will complain about the shadowed template parameter. 7686 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 7687 // Just pretend that we didn't see the previous declaration. 7688 PrevDecl = 0; 7689 } 7690 7691 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 7692 PrevDecl = 0; 7693 7694 bool Mutable 7695 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 7696 SourceLocation TSSL = D.getSourceRange().getBegin(); 7697 FieldDecl *NewFD 7698 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, HasInit, 7699 TSSL, AS, PrevDecl, &D); 7700 7701 if (NewFD->isInvalidDecl()) 7702 Record->setInvalidDecl(); 7703 7704 if (NewFD->isInvalidDecl() && PrevDecl) { 7705 // Don't introduce NewFD into scope; there's already something 7706 // with the same name in the same scope. 7707 } else if (II) { 7708 PushOnScopeChains(NewFD, S); 7709 } else 7710 Record->addDecl(NewFD); 7711 7712 return NewFD; 7713} 7714 7715/// \brief Build a new FieldDecl and check its well-formedness. 7716/// 7717/// This routine builds a new FieldDecl given the fields name, type, 7718/// record, etc. \p PrevDecl should refer to any previous declaration 7719/// with the same name and in the same scope as the field to be 7720/// created. 7721/// 7722/// \returns a new FieldDecl. 7723/// 7724/// \todo The Declarator argument is a hack. It will be removed once 7725FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 7726 TypeSourceInfo *TInfo, 7727 RecordDecl *Record, SourceLocation Loc, 7728 bool Mutable, Expr *BitWidth, bool HasInit, 7729 SourceLocation TSSL, 7730 AccessSpecifier AS, NamedDecl *PrevDecl, 7731 Declarator *D) { 7732 IdentifierInfo *II = Name.getAsIdentifierInfo(); 7733 bool InvalidDecl = false; 7734 if (D) InvalidDecl = D->isInvalidType(); 7735 7736 // If we receive a broken type, recover by assuming 'int' and 7737 // marking this declaration as invalid. 7738 if (T.isNull()) { 7739 InvalidDecl = true; 7740 T = Context.IntTy; 7741 } 7742 7743 QualType EltTy = Context.getBaseElementType(T); 7744 if (!EltTy->isDependentType() && 7745 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 7746 // Fields of incomplete type force their record to be invalid. 7747 Record->setInvalidDecl(); 7748 InvalidDecl = true; 7749 } 7750 7751 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7752 // than a variably modified type. 7753 if (!InvalidDecl && T->isVariablyModifiedType()) { 7754 bool SizeIsNegative; 7755 llvm::APSInt Oversized; 7756 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 7757 SizeIsNegative, 7758 Oversized); 7759 if (!FixedTy.isNull()) { 7760 Diag(Loc, diag::warn_illegal_constant_array_size); 7761 T = FixedTy; 7762 } else { 7763 if (SizeIsNegative) 7764 Diag(Loc, diag::err_typecheck_negative_array_size); 7765 else if (Oversized.getBoolValue()) 7766 Diag(Loc, diag::err_array_too_large) 7767 << Oversized.toString(10); 7768 else 7769 Diag(Loc, diag::err_typecheck_field_variable_size); 7770 InvalidDecl = true; 7771 } 7772 } 7773 7774 // Fields can not have abstract class types 7775 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 7776 diag::err_abstract_type_in_decl, 7777 AbstractFieldType)) 7778 InvalidDecl = true; 7779 7780 bool ZeroWidth = false; 7781 // If this is declared as a bit-field, check the bit-field. 7782 if (!InvalidDecl && BitWidth && 7783 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 7784 InvalidDecl = true; 7785 BitWidth = 0; 7786 ZeroWidth = false; 7787 } 7788 7789 // Check that 'mutable' is consistent with the type of the declaration. 7790 if (!InvalidDecl && Mutable) { 7791 unsigned DiagID = 0; 7792 if (T->isReferenceType()) 7793 DiagID = diag::err_mutable_reference; 7794 else if (T.isConstQualified()) 7795 DiagID = diag::err_mutable_const; 7796 7797 if (DiagID) { 7798 SourceLocation ErrLoc = Loc; 7799 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 7800 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 7801 Diag(ErrLoc, DiagID); 7802 Mutable = false; 7803 InvalidDecl = true; 7804 } 7805 } 7806 7807 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, 7808 BitWidth, Mutable, HasInit); 7809 if (InvalidDecl) 7810 NewFD->setInvalidDecl(); 7811 7812 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 7813 Diag(Loc, diag::err_duplicate_member) << II; 7814 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7815 NewFD->setInvalidDecl(); 7816 } 7817 7818 if (!InvalidDecl && getLangOptions().CPlusPlus) { 7819 if (Record->isUnion()) { 7820 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7821 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7822 if (RDecl->getDefinition()) { 7823 // C++ [class.union]p1: An object of a class with a non-trivial 7824 // constructor, a non-trivial copy constructor, a non-trivial 7825 // destructor, or a non-trivial copy assignment operator 7826 // cannot be a member of a union, nor can an array of such 7827 // objects. 7828 if (!getLangOptions().CPlusPlus0x && CheckNontrivialField(NewFD)) 7829 NewFD->setInvalidDecl(); 7830 } 7831 } 7832 7833 // C++ [class.union]p1: If a union contains a member of reference type, 7834 // the program is ill-formed. 7835 if (EltTy->isReferenceType()) { 7836 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 7837 << NewFD->getDeclName() << EltTy; 7838 NewFD->setInvalidDecl(); 7839 } 7840 } 7841 } 7842 7843 // FIXME: We need to pass in the attributes given an AST 7844 // representation, not a parser representation. 7845 if (D) 7846 // FIXME: What to pass instead of TUScope? 7847 ProcessDeclAttributes(TUScope, NewFD, *D); 7848 7849 // In auto-retain/release, infer strong retension for fields of 7850 // retainable type. 7851 if (getLangOptions().ObjCAutoRefCount && inferObjCARCLifetime(NewFD)) 7852 NewFD->setInvalidDecl(); 7853 7854 if (T.isObjCGCWeak()) 7855 Diag(Loc, diag::warn_attribute_weak_on_field); 7856 7857 NewFD->setAccess(AS); 7858 return NewFD; 7859} 7860 7861bool Sema::CheckNontrivialField(FieldDecl *FD) { 7862 assert(FD); 7863 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 7864 7865 if (FD->isInvalidDecl()) 7866 return true; 7867 7868 QualType EltTy = Context.getBaseElementType(FD->getType()); 7869 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7870 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7871 if (RDecl->getDefinition()) { 7872 // We check for copy constructors before constructors 7873 // because otherwise we'll never get complaints about 7874 // copy constructors. 7875 7876 CXXSpecialMember member = CXXInvalid; 7877 if (!RDecl->hasTrivialCopyConstructor()) 7878 member = CXXCopyConstructor; 7879 else if (!RDecl->hasTrivialDefaultConstructor()) 7880 member = CXXDefaultConstructor; 7881 else if (!RDecl->hasTrivialCopyAssignment()) 7882 member = CXXCopyAssignment; 7883 else if (!RDecl->hasTrivialDestructor()) 7884 member = CXXDestructor; 7885 7886 if (member != CXXInvalid) { 7887 if (getLangOptions().ObjCAutoRefCount && RDecl->hasObjectMember()) { 7888 // Objective-C++ ARC: it is an error to have a non-trivial field of 7889 // a union. However, system headers in Objective-C programs 7890 // occasionally have Objective-C lifetime objects within unions, 7891 // and rather than cause the program to fail, we make those 7892 // members unavailable. 7893 SourceLocation Loc = FD->getLocation(); 7894 if (getSourceManager().isInSystemHeader(Loc)) { 7895 if (!FD->hasAttr<UnavailableAttr>()) 7896 FD->addAttr(new (Context) UnavailableAttr(Loc, Context, 7897 "this system field has retaining ownership")); 7898 return false; 7899 } 7900 } 7901 7902 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7903 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7904 DiagnoseNontrivial(RT, member); 7905 return true; 7906 } 7907 } 7908 } 7909 7910 return false; 7911} 7912 7913/// DiagnoseNontrivial - Given that a class has a non-trivial 7914/// special member, figure out why. 7915void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7916 QualType QT(T, 0U); 7917 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7918 7919 // Check whether the member was user-declared. 7920 switch (member) { 7921 case CXXInvalid: 7922 break; 7923 7924 case CXXDefaultConstructor: 7925 if (RD->hasUserDeclaredConstructor()) { 7926 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7927 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7928 const FunctionDecl *body = 0; 7929 ci->hasBody(body); 7930 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7931 SourceLocation CtorLoc = ci->getLocation(); 7932 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7933 return; 7934 } 7935 } 7936 7937 assert(0 && "found no user-declared constructors"); 7938 return; 7939 } 7940 break; 7941 7942 case CXXCopyConstructor: 7943 if (RD->hasUserDeclaredCopyConstructor()) { 7944 SourceLocation CtorLoc = 7945 RD->getCopyConstructor(0)->getLocation(); 7946 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7947 return; 7948 } 7949 break; 7950 7951 case CXXMoveConstructor: 7952 if (RD->hasUserDeclaredMoveConstructor()) { 7953 SourceLocation CtorLoc = RD->getMoveConstructor()->getLocation(); 7954 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7955 return; 7956 } 7957 break; 7958 7959 case CXXCopyAssignment: 7960 if (RD->hasUserDeclaredCopyAssignment()) { 7961 // FIXME: this should use the location of the copy 7962 // assignment, not the type. 7963 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7964 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7965 return; 7966 } 7967 break; 7968 7969 case CXXMoveAssignment: 7970 if (RD->hasUserDeclaredMoveAssignment()) { 7971 SourceLocation AssignLoc = RD->getMoveAssignmentOperator()->getLocation(); 7972 Diag(AssignLoc, diag::note_nontrivial_user_defined) << QT << member; 7973 return; 7974 } 7975 break; 7976 7977 case CXXDestructor: 7978 if (RD->hasUserDeclaredDestructor()) { 7979 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7980 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7981 return; 7982 } 7983 break; 7984 } 7985 7986 typedef CXXRecordDecl::base_class_iterator base_iter; 7987 7988 // Virtual bases and members inhibit trivial copying/construction, 7989 // but not trivial destruction. 7990 if (member != CXXDestructor) { 7991 // Check for virtual bases. vbases includes indirect virtual bases, 7992 // so we just iterate through the direct bases. 7993 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7994 if (bi->isVirtual()) { 7995 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7996 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7997 return; 7998 } 7999 8000 // Check for virtual methods. 8001 typedef CXXRecordDecl::method_iterator meth_iter; 8002 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 8003 ++mi) { 8004 if (mi->isVirtual()) { 8005 SourceLocation MLoc = mi->getSourceRange().getBegin(); 8006 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 8007 return; 8008 } 8009 } 8010 } 8011 8012 bool (CXXRecordDecl::*hasTrivial)() const; 8013 switch (member) { 8014 case CXXDefaultConstructor: 8015 hasTrivial = &CXXRecordDecl::hasTrivialDefaultConstructor; break; 8016 case CXXCopyConstructor: 8017 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 8018 case CXXCopyAssignment: 8019 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 8020 case CXXDestructor: 8021 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 8022 default: 8023 assert(0 && "unexpected special member"); return; 8024 } 8025 8026 // Check for nontrivial bases (and recurse). 8027 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 8028 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 8029 assert(BaseRT && "Don't know how to handle dependent bases"); 8030 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 8031 if (!(BaseRecTy->*hasTrivial)()) { 8032 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 8033 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 8034 DiagnoseNontrivial(BaseRT, member); 8035 return; 8036 } 8037 } 8038 8039 // Check for nontrivial members (and recurse). 8040 typedef RecordDecl::field_iterator field_iter; 8041 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 8042 ++fi) { 8043 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 8044 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 8045 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 8046 8047 if (!(EltRD->*hasTrivial)()) { 8048 SourceLocation FLoc = (*fi)->getLocation(); 8049 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 8050 DiagnoseNontrivial(EltRT, member); 8051 return; 8052 } 8053 } 8054 8055 if (EltTy->isObjCLifetimeType()) { 8056 switch (EltTy.getObjCLifetime()) { 8057 case Qualifiers::OCL_None: 8058 case Qualifiers::OCL_ExplicitNone: 8059 break; 8060 8061 case Qualifiers::OCL_Autoreleasing: 8062 case Qualifiers::OCL_Weak: 8063 case Qualifiers::OCL_Strong: 8064 Diag((*fi)->getLocation(), diag::note_nontrivial_objc_ownership) 8065 << QT << EltTy.getObjCLifetime(); 8066 return; 8067 } 8068 } 8069 } 8070 8071 assert(0 && "found no explanation for non-trivial member"); 8072} 8073 8074/// TranslateIvarVisibility - Translate visibility from a token ID to an 8075/// AST enum value. 8076static ObjCIvarDecl::AccessControl 8077TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 8078 switch (ivarVisibility) { 8079 default: assert(0 && "Unknown visitibility kind"); 8080 case tok::objc_private: return ObjCIvarDecl::Private; 8081 case tok::objc_public: return ObjCIvarDecl::Public; 8082 case tok::objc_protected: return ObjCIvarDecl::Protected; 8083 case tok::objc_package: return ObjCIvarDecl::Package; 8084 } 8085} 8086 8087/// ActOnIvar - Each ivar field of an objective-c class is passed into this 8088/// in order to create an IvarDecl object for it. 8089Decl *Sema::ActOnIvar(Scope *S, 8090 SourceLocation DeclStart, 8091 Decl *IntfDecl, 8092 Declarator &D, ExprTy *BitfieldWidth, 8093 tok::ObjCKeywordKind Visibility) { 8094 8095 IdentifierInfo *II = D.getIdentifier(); 8096 Expr *BitWidth = (Expr*)BitfieldWidth; 8097 SourceLocation Loc = DeclStart; 8098 if (II) Loc = D.getIdentifierLoc(); 8099 8100 // FIXME: Unnamed fields can be handled in various different ways, for 8101 // example, unnamed unions inject all members into the struct namespace! 8102 8103 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 8104 QualType T = TInfo->getType(); 8105 8106 if (BitWidth) { 8107 // 6.7.2.1p3, 6.7.2.1p4 8108 if (VerifyBitField(Loc, II, T, BitWidth)) { 8109 D.setInvalidType(); 8110 BitWidth = 0; 8111 } 8112 } else { 8113 // Not a bitfield. 8114 8115 // validate II. 8116 8117 } 8118 if (T->isReferenceType()) { 8119 Diag(Loc, diag::err_ivar_reference_type); 8120 D.setInvalidType(); 8121 } 8122 // C99 6.7.2.1p8: A member of a structure or union may have any type other 8123 // than a variably modified type. 8124 else if (T->isVariablyModifiedType()) { 8125 Diag(Loc, diag::err_typecheck_ivar_variable_size); 8126 D.setInvalidType(); 8127 } 8128 8129 // Get the visibility (access control) for this ivar. 8130 ObjCIvarDecl::AccessControl ac = 8131 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 8132 : ObjCIvarDecl::None; 8133 // Must set ivar's DeclContext to its enclosing interface. 8134 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 8135 ObjCContainerDecl *EnclosingContext; 8136 if (ObjCImplementationDecl *IMPDecl = 8137 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 8138 if (!LangOpts.ObjCNonFragileABI2) { 8139 // Case of ivar declared in an implementation. Context is that of its class. 8140 EnclosingContext = IMPDecl->getClassInterface(); 8141 assert(EnclosingContext && "Implementation has no class interface!"); 8142 } 8143 else 8144 EnclosingContext = EnclosingDecl; 8145 } else { 8146 if (ObjCCategoryDecl *CDecl = 8147 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 8148 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 8149 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 8150 return 0; 8151 } 8152 } 8153 EnclosingContext = EnclosingDecl; 8154 } 8155 8156 // Construct the decl. 8157 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, 8158 DeclStart, Loc, II, T, 8159 TInfo, ac, (Expr *)BitfieldWidth); 8160 8161 if (II) { 8162 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 8163 ForRedeclaration); 8164 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 8165 && !isa<TagDecl>(PrevDecl)) { 8166 Diag(Loc, diag::err_duplicate_member) << II; 8167 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 8168 NewID->setInvalidDecl(); 8169 } 8170 } 8171 8172 // Process attributes attached to the ivar. 8173 ProcessDeclAttributes(S, NewID, D); 8174 8175 if (D.isInvalidType()) 8176 NewID->setInvalidDecl(); 8177 8178 // In ARC, infer 'retaining' for ivars of retainable type. 8179 if (getLangOptions().ObjCAutoRefCount && inferObjCARCLifetime(NewID)) 8180 NewID->setInvalidDecl(); 8181 8182 if (II) { 8183 // FIXME: When interfaces are DeclContexts, we'll need to add 8184 // these to the interface. 8185 S->AddDecl(NewID); 8186 IdResolver.AddDecl(NewID); 8187 } 8188 8189 return NewID; 8190} 8191 8192/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 8193/// class and class extensions. For every class @interface and class 8194/// extension @interface, if the last ivar is a bitfield of any type, 8195/// then add an implicit `char :0` ivar to the end of that interface. 8196void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 8197 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 8198 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 8199 return; 8200 8201 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 8202 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 8203 8204 if (!Ivar->isBitField()) 8205 return; 8206 uint64_t BitFieldSize = 8207 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 8208 if (BitFieldSize == 0) 8209 return; 8210 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 8211 if (!ID) { 8212 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 8213 if (!CD->IsClassExtension()) 8214 return; 8215 } 8216 // No need to add this to end of @implementation. 8217 else 8218 return; 8219 } 8220 // All conditions are met. Add a new bitfield to the tail end of ivars. 8221 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 8222 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 8223 8224 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 8225 DeclLoc, DeclLoc, 0, 8226 Context.CharTy, 8227 Context.CreateTypeSourceInfo(Context.CharTy), 8228 ObjCIvarDecl::Private, BW, 8229 true); 8230 AllIvarDecls.push_back(Ivar); 8231} 8232 8233void Sema::ActOnFields(Scope* S, 8234 SourceLocation RecLoc, Decl *EnclosingDecl, 8235 Decl **Fields, unsigned NumFields, 8236 SourceLocation LBrac, SourceLocation RBrac, 8237 AttributeList *Attr) { 8238 assert(EnclosingDecl && "missing record or interface decl"); 8239 8240 // If the decl this is being inserted into is invalid, then it may be a 8241 // redeclaration or some other bogus case. Don't try to add fields to it. 8242 if (EnclosingDecl->isInvalidDecl()) { 8243 // FIXME: Deallocate fields? 8244 return; 8245 } 8246 8247 8248 // Verify that all the fields are okay. 8249 unsigned NumNamedMembers = 0; 8250 llvm::SmallVector<FieldDecl*, 32> RecFields; 8251 8252 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 8253 bool ARCErrReported = false; 8254 for (unsigned i = 0; i != NumFields; ++i) { 8255 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 8256 8257 // Get the type for the field. 8258 const Type *FDTy = FD->getType().getTypePtr(); 8259 8260 if (!FD->isAnonymousStructOrUnion()) { 8261 // Remember all fields written by the user. 8262 RecFields.push_back(FD); 8263 } 8264 8265 // If the field is already invalid for some reason, don't emit more 8266 // diagnostics about it. 8267 if (FD->isInvalidDecl()) { 8268 EnclosingDecl->setInvalidDecl(); 8269 continue; 8270 } 8271 8272 // C99 6.7.2.1p2: 8273 // A structure or union shall not contain a member with 8274 // incomplete or function type (hence, a structure shall not 8275 // contain an instance of itself, but may contain a pointer to 8276 // an instance of itself), except that the last member of a 8277 // structure with more than one named member may have incomplete 8278 // array type; such a structure (and any union containing, 8279 // possibly recursively, a member that is such a structure) 8280 // shall not be a member of a structure or an element of an 8281 // array. 8282 if (FDTy->isFunctionType()) { 8283 // Field declared as a function. 8284 Diag(FD->getLocation(), diag::err_field_declared_as_function) 8285 << FD->getDeclName(); 8286 FD->setInvalidDecl(); 8287 EnclosingDecl->setInvalidDecl(); 8288 continue; 8289 } else if (FDTy->isIncompleteArrayType() && Record && 8290 ((i == NumFields - 1 && !Record->isUnion()) || 8291 ((getLangOptions().Microsoft || getLangOptions().CPlusPlus) && 8292 (i == NumFields - 1 || Record->isUnion())))) { 8293 // Flexible array member. 8294 // Microsoft and g++ is more permissive regarding flexible array. 8295 // It will accept flexible array in union and also 8296 // as the sole element of a struct/class. 8297 if (getLangOptions().Microsoft) { 8298 if (Record->isUnion()) 8299 Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) 8300 << FD->getDeclName(); 8301 else if (NumFields == 1) 8302 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) 8303 << FD->getDeclName() << Record->getTagKind(); 8304 } else if (getLangOptions().CPlusPlus) { 8305 if (Record->isUnion()) 8306 Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) 8307 << FD->getDeclName(); 8308 else if (NumFields == 1) 8309 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) 8310 << FD->getDeclName() << Record->getTagKind(); 8311 } else if (NumNamedMembers < 1) { 8312 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 8313 << FD->getDeclName(); 8314 FD->setInvalidDecl(); 8315 EnclosingDecl->setInvalidDecl(); 8316 continue; 8317 } 8318 if (!FD->getType()->isDependentType() && 8319 !Context.getBaseElementType(FD->getType()).isPODType(Context)) { 8320 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 8321 << FD->getDeclName() << FD->getType(); 8322 FD->setInvalidDecl(); 8323 EnclosingDecl->setInvalidDecl(); 8324 continue; 8325 } 8326 // Okay, we have a legal flexible array member at the end of the struct. 8327 if (Record) 8328 Record->setHasFlexibleArrayMember(true); 8329 } else if (!FDTy->isDependentType() && 8330 RequireCompleteType(FD->getLocation(), FD->getType(), 8331 diag::err_field_incomplete)) { 8332 // Incomplete type 8333 FD->setInvalidDecl(); 8334 EnclosingDecl->setInvalidDecl(); 8335 continue; 8336 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 8337 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 8338 // If this is a member of a union, then entire union becomes "flexible". 8339 if (Record && Record->isUnion()) { 8340 Record->setHasFlexibleArrayMember(true); 8341 } else { 8342 // If this is a struct/class and this is not the last element, reject 8343 // it. Note that GCC supports variable sized arrays in the middle of 8344 // structures. 8345 if (i != NumFields-1) 8346 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 8347 << FD->getDeclName() << FD->getType(); 8348 else { 8349 // We support flexible arrays at the end of structs in 8350 // other structs as an extension. 8351 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 8352 << FD->getDeclName(); 8353 if (Record) 8354 Record->setHasFlexibleArrayMember(true); 8355 } 8356 } 8357 } 8358 if (Record && FDTTy->getDecl()->hasObjectMember()) 8359 Record->setHasObjectMember(true); 8360 } else if (FDTy->isObjCObjectType()) { 8361 /// A field cannot be an Objective-c object 8362 Diag(FD->getLocation(), diag::err_statically_allocated_object); 8363 FD->setInvalidDecl(); 8364 EnclosingDecl->setInvalidDecl(); 8365 continue; 8366 } 8367 else if (!getLangOptions().CPlusPlus) { 8368 if (getLangOptions().ObjCAutoRefCount && Record && !ARCErrReported) { 8369 // It's an error in ARC if a field has lifetime. 8370 // We don't want to report this in a system header, though, 8371 // so we just make the field unavailable. 8372 // FIXME: that's really not sufficient; we need to make the type 8373 // itself invalid to, say, initialize or copy. 8374 QualType T = FD->getType(); 8375 Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime(); 8376 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) { 8377 SourceLocation loc = FD->getLocation(); 8378 if (getSourceManager().isInSystemHeader(loc)) { 8379 if (!FD->hasAttr<UnavailableAttr>()) { 8380 FD->addAttr(new (Context) UnavailableAttr(loc, Context, 8381 "this system field has retaining ownership")); 8382 } 8383 } else { 8384 Diag(FD->getLocation(), diag::err_arc_objc_object_in_struct); 8385 } 8386 ARCErrReported = true; 8387 } 8388 } 8389 else if (getLangOptions().ObjC1 && 8390 getLangOptions().getGCMode() != LangOptions::NonGC && 8391 Record && !Record->hasObjectMember()) { 8392 if (FD->getType()->isObjCObjectPointerType() || 8393 FD->getType().isObjCGCStrong()) 8394 Record->setHasObjectMember(true); 8395 else if (Context.getAsArrayType(FD->getType())) { 8396 QualType BaseType = Context.getBaseElementType(FD->getType()); 8397 if (BaseType->isRecordType() && 8398 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 8399 Record->setHasObjectMember(true); 8400 else if (BaseType->isObjCObjectPointerType() || 8401 BaseType.isObjCGCStrong()) 8402 Record->setHasObjectMember(true); 8403 } 8404 } 8405 } 8406 // Keep track of the number of named members. 8407 if (FD->getIdentifier()) 8408 ++NumNamedMembers; 8409 } 8410 8411 // Okay, we successfully defined 'Record'. 8412 if (Record) { 8413 bool Completed = false; 8414 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 8415 if (!CXXRecord->isInvalidDecl()) { 8416 // Set access bits correctly on the directly-declared conversions. 8417 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 8418 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 8419 I != E; ++I) 8420 Convs->setAccess(I, (*I)->getAccess()); 8421 8422 if (!CXXRecord->isDependentType()) { 8423 // Objective-C Automatic Reference Counting: 8424 // If a class has a non-static data member of Objective-C pointer 8425 // type (or array thereof), it is a non-POD type and its 8426 // default constructor (if any), copy constructor, copy assignment 8427 // operator, and destructor are non-trivial. 8428 // 8429 // This rule is also handled by CXXRecordDecl::completeDefinition(). 8430 // However, here we check whether this particular class is only 8431 // non-POD because of the presence of an Objective-C pointer member. 8432 // If so, objects of this type cannot be shared between code compiled 8433 // with instant objects and code compiled with manual retain/release. 8434 if (getLangOptions().ObjCAutoRefCount && 8435 CXXRecord->hasObjectMember() && 8436 CXXRecord->getLinkage() == ExternalLinkage) { 8437 if (CXXRecord->isPOD()) { 8438 Diag(CXXRecord->getLocation(), 8439 diag::warn_arc_non_pod_class_with_object_member) 8440 << CXXRecord; 8441 } else { 8442 // FIXME: Fix-Its would be nice here, but finding a good location 8443 // for them is going to be tricky. 8444 if (CXXRecord->hasTrivialCopyConstructor()) 8445 Diag(CXXRecord->getLocation(), 8446 diag::warn_arc_trivial_member_function_with_object_member) 8447 << CXXRecord << 0; 8448 if (CXXRecord->hasTrivialCopyAssignment()) 8449 Diag(CXXRecord->getLocation(), 8450 diag::warn_arc_trivial_member_function_with_object_member) 8451 << CXXRecord << 1; 8452 if (CXXRecord->hasTrivialDestructor()) 8453 Diag(CXXRecord->getLocation(), 8454 diag::warn_arc_trivial_member_function_with_object_member) 8455 << CXXRecord << 2; 8456 } 8457 } 8458 8459 // Adjust user-defined destructor exception spec. 8460 if (getLangOptions().CPlusPlus0x && 8461 CXXRecord->hasUserDeclaredDestructor()) 8462 AdjustDestructorExceptionSpec(CXXRecord,CXXRecord->getDestructor()); 8463 8464 // Add any implicitly-declared members to this class. 8465 AddImplicitlyDeclaredMembersToClass(CXXRecord); 8466 8467 // If we have virtual base classes, we may end up finding multiple 8468 // final overriders for a given virtual function. Check for this 8469 // problem now. 8470 if (CXXRecord->getNumVBases()) { 8471 CXXFinalOverriderMap FinalOverriders; 8472 CXXRecord->getFinalOverriders(FinalOverriders); 8473 8474 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 8475 MEnd = FinalOverriders.end(); 8476 M != MEnd; ++M) { 8477 for (OverridingMethods::iterator SO = M->second.begin(), 8478 SOEnd = M->second.end(); 8479 SO != SOEnd; ++SO) { 8480 assert(SO->second.size() > 0 && 8481 "Virtual function without overridding functions?"); 8482 if (SO->second.size() == 1) 8483 continue; 8484 8485 // C++ [class.virtual]p2: 8486 // In a derived class, if a virtual member function of a base 8487 // class subobject has more than one final overrider the 8488 // program is ill-formed. 8489 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 8490 << (NamedDecl *)M->first << Record; 8491 Diag(M->first->getLocation(), 8492 diag::note_overridden_virtual_function); 8493 for (OverridingMethods::overriding_iterator 8494 OM = SO->second.begin(), 8495 OMEnd = SO->second.end(); 8496 OM != OMEnd; ++OM) 8497 Diag(OM->Method->getLocation(), diag::note_final_overrider) 8498 << (NamedDecl *)M->first << OM->Method->getParent(); 8499 8500 Record->setInvalidDecl(); 8501 } 8502 } 8503 CXXRecord->completeDefinition(&FinalOverriders); 8504 Completed = true; 8505 } 8506 } 8507 } 8508 } 8509 8510 if (!Completed) 8511 Record->completeDefinition(); 8512 8513 // Now that the record is complete, do any delayed exception spec checks 8514 // we were missing. 8515 while (!DelayedDestructorExceptionSpecChecks.empty()) { 8516 const CXXDestructorDecl *Dtor = 8517 DelayedDestructorExceptionSpecChecks.back().first; 8518 if (Dtor->getParent() != Record) 8519 break; 8520 8521 assert(!Dtor->getParent()->isDependentType() && 8522 "Should not ever add destructors of templates into the list."); 8523 CheckOverridingFunctionExceptionSpec(Dtor, 8524 DelayedDestructorExceptionSpecChecks.back().second); 8525 DelayedDestructorExceptionSpecChecks.pop_back(); 8526 } 8527 8528 } else { 8529 ObjCIvarDecl **ClsFields = 8530 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 8531 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 8532 ID->setLocEnd(RBrac); 8533 // Add ivar's to class's DeclContext. 8534 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 8535 ClsFields[i]->setLexicalDeclContext(ID); 8536 ID->addDecl(ClsFields[i]); 8537 } 8538 // Must enforce the rule that ivars in the base classes may not be 8539 // duplicates. 8540 if (ID->getSuperClass()) 8541 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 8542 } else if (ObjCImplementationDecl *IMPDecl = 8543 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 8544 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 8545 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 8546 // Ivar declared in @implementation never belongs to the implementation. 8547 // Only it is in implementation's lexical context. 8548 ClsFields[I]->setLexicalDeclContext(IMPDecl); 8549 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 8550 } else if (ObjCCategoryDecl *CDecl = 8551 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 8552 // case of ivars in class extension; all other cases have been 8553 // reported as errors elsewhere. 8554 // FIXME. Class extension does not have a LocEnd field. 8555 // CDecl->setLocEnd(RBrac); 8556 // Add ivar's to class extension's DeclContext. 8557 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 8558 ClsFields[i]->setLexicalDeclContext(CDecl); 8559 CDecl->addDecl(ClsFields[i]); 8560 } 8561 } 8562 } 8563 8564 if (Attr) 8565 ProcessDeclAttributeList(S, Record, Attr); 8566 8567 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 8568 // set the visibility of this record. 8569 if (Record && !Record->getDeclContext()->isRecord()) 8570 AddPushedVisibilityAttribute(Record); 8571} 8572 8573/// \brief Determine whether the given integral value is representable within 8574/// the given type T. 8575static bool isRepresentableIntegerValue(ASTContext &Context, 8576 llvm::APSInt &Value, 8577 QualType T) { 8578 assert(T->isIntegralType(Context) && "Integral type required!"); 8579 unsigned BitWidth = Context.getIntWidth(T); 8580 8581 if (Value.isUnsigned() || Value.isNonNegative()) { 8582 if (T->isSignedIntegerOrEnumerationType()) 8583 --BitWidth; 8584 return Value.getActiveBits() <= BitWidth; 8585 } 8586 return Value.getMinSignedBits() <= BitWidth; 8587} 8588 8589// \brief Given an integral type, return the next larger integral type 8590// (or a NULL type of no such type exists). 8591static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 8592 // FIXME: Int128/UInt128 support, which also needs to be introduced into 8593 // enum checking below. 8594 assert(T->isIntegralType(Context) && "Integral type required!"); 8595 const unsigned NumTypes = 4; 8596 QualType SignedIntegralTypes[NumTypes] = { 8597 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 8598 }; 8599 QualType UnsignedIntegralTypes[NumTypes] = { 8600 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 8601 Context.UnsignedLongLongTy 8602 }; 8603 8604 unsigned BitWidth = Context.getTypeSize(T); 8605 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes 8606 : UnsignedIntegralTypes; 8607 for (unsigned I = 0; I != NumTypes; ++I) 8608 if (Context.getTypeSize(Types[I]) > BitWidth) 8609 return Types[I]; 8610 8611 return QualType(); 8612} 8613 8614EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 8615 EnumConstantDecl *LastEnumConst, 8616 SourceLocation IdLoc, 8617 IdentifierInfo *Id, 8618 Expr *Val) { 8619 unsigned IntWidth = Context.Target.getIntWidth(); 8620 llvm::APSInt EnumVal(IntWidth); 8621 QualType EltTy; 8622 8623 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 8624 Val = 0; 8625 8626 if (Val) { 8627 if (Enum->isDependentType() || Val->isTypeDependent()) 8628 EltTy = Context.DependentTy; 8629 else { 8630 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 8631 SourceLocation ExpLoc; 8632 if (!Val->isValueDependent() && 8633 VerifyIntegerConstantExpression(Val, &EnumVal)) { 8634 Val = 0; 8635 } else { 8636 if (!getLangOptions().CPlusPlus) { 8637 // C99 6.7.2.2p2: 8638 // The expression that defines the value of an enumeration constant 8639 // shall be an integer constant expression that has a value 8640 // representable as an int. 8641 8642 // Complain if the value is not representable in an int. 8643 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 8644 Diag(IdLoc, diag::ext_enum_value_not_int) 8645 << EnumVal.toString(10) << Val->getSourceRange() 8646 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 8647 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 8648 // Force the type of the expression to 'int'. 8649 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).take(); 8650 } 8651 } 8652 8653 if (Enum->isFixed()) { 8654 EltTy = Enum->getIntegerType(); 8655 8656 // C++0x [dcl.enum]p5: 8657 // ... if the initializing value of an enumerator cannot be 8658 // represented by the underlying type, the program is ill-formed. 8659 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 8660 if (getLangOptions().Microsoft) { 8661 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 8662 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 8663 } else 8664 Diag(IdLoc, diag::err_enumerator_too_large) 8665 << EltTy; 8666 } else 8667 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 8668 } 8669 else { 8670 // C++0x [dcl.enum]p5: 8671 // If the underlying type is not fixed, the type of each enumerator 8672 // is the type of its initializing value: 8673 // - If an initializer is specified for an enumerator, the 8674 // initializing value has the same type as the expression. 8675 EltTy = Val->getType(); 8676 } 8677 } 8678 } 8679 } 8680 8681 if (!Val) { 8682 if (Enum->isDependentType()) 8683 EltTy = Context.DependentTy; 8684 else if (!LastEnumConst) { 8685 // C++0x [dcl.enum]p5: 8686 // If the underlying type is not fixed, the type of each enumerator 8687 // is the type of its initializing value: 8688 // - If no initializer is specified for the first enumerator, the 8689 // initializing value has an unspecified integral type. 8690 // 8691 // GCC uses 'int' for its unspecified integral type, as does 8692 // C99 6.7.2.2p3. 8693 if (Enum->isFixed()) { 8694 EltTy = Enum->getIntegerType(); 8695 } 8696 else { 8697 EltTy = Context.IntTy; 8698 } 8699 } else { 8700 // Assign the last value + 1. 8701 EnumVal = LastEnumConst->getInitVal(); 8702 ++EnumVal; 8703 EltTy = LastEnumConst->getType(); 8704 8705 // Check for overflow on increment. 8706 if (EnumVal < LastEnumConst->getInitVal()) { 8707 // C++0x [dcl.enum]p5: 8708 // If the underlying type is not fixed, the type of each enumerator 8709 // is the type of its initializing value: 8710 // 8711 // - Otherwise the type of the initializing value is the same as 8712 // the type of the initializing value of the preceding enumerator 8713 // unless the incremented value is not representable in that type, 8714 // in which case the type is an unspecified integral type 8715 // sufficient to contain the incremented value. If no such type 8716 // exists, the program is ill-formed. 8717 QualType T = getNextLargerIntegralType(Context, EltTy); 8718 if (T.isNull() || Enum->isFixed()) { 8719 // There is no integral type larger enough to represent this 8720 // value. Complain, then allow the value to wrap around. 8721 EnumVal = LastEnumConst->getInitVal(); 8722 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 8723 ++EnumVal; 8724 if (Enum->isFixed()) 8725 // When the underlying type is fixed, this is ill-formed. 8726 Diag(IdLoc, diag::err_enumerator_wrapped) 8727 << EnumVal.toString(10) 8728 << EltTy; 8729 else 8730 Diag(IdLoc, diag::warn_enumerator_too_large) 8731 << EnumVal.toString(10); 8732 } else { 8733 EltTy = T; 8734 } 8735 8736 // Retrieve the last enumerator's value, extent that type to the 8737 // type that is supposed to be large enough to represent the incremented 8738 // value, then increment. 8739 EnumVal = LastEnumConst->getInitVal(); 8740 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType()); 8741 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 8742 ++EnumVal; 8743 8744 // If we're not in C++, diagnose the overflow of enumerator values, 8745 // which in C99 means that the enumerator value is not representable in 8746 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 8747 // permits enumerator values that are representable in some larger 8748 // integral type. 8749 if (!getLangOptions().CPlusPlus && !T.isNull()) 8750 Diag(IdLoc, diag::warn_enum_value_overflow); 8751 } else if (!getLangOptions().CPlusPlus && 8752 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 8753 // Enforce C99 6.7.2.2p2 even when we compute the next value. 8754 Diag(IdLoc, diag::ext_enum_value_not_int) 8755 << EnumVal.toString(10) << 1; 8756 } 8757 } 8758 } 8759 8760 if (!EltTy->isDependentType()) { 8761 // Make the enumerator value match the signedness and size of the 8762 // enumerator's type. 8763 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 8764 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType()); 8765 } 8766 8767 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 8768 Val, EnumVal); 8769} 8770 8771 8772Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 8773 SourceLocation IdLoc, IdentifierInfo *Id, 8774 AttributeList *Attr, 8775 SourceLocation EqualLoc, ExprTy *val) { 8776 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 8777 EnumConstantDecl *LastEnumConst = 8778 cast_or_null<EnumConstantDecl>(lastEnumConst); 8779 Expr *Val = static_cast<Expr*>(val); 8780 8781 // The scope passed in may not be a decl scope. Zip up the scope tree until 8782 // we find one that is. 8783 S = getNonFieldDeclScope(S); 8784 8785 // Verify that there isn't already something declared with this name in this 8786 // scope. 8787 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 8788 ForRedeclaration); 8789 if (PrevDecl && PrevDecl->isTemplateParameter()) { 8790 // Maybe we will complain about the shadowed template parameter. 8791 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 8792 // Just pretend that we didn't see the previous declaration. 8793 PrevDecl = 0; 8794 } 8795 8796 if (PrevDecl) { 8797 // When in C++, we may get a TagDecl with the same name; in this case the 8798 // enum constant will 'hide' the tag. 8799 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 8800 "Received TagDecl when not in C++!"); 8801 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 8802 if (isa<EnumConstantDecl>(PrevDecl)) 8803 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 8804 else 8805 Diag(IdLoc, diag::err_redefinition) << Id; 8806 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 8807 return 0; 8808 } 8809 } 8810 8811 // C++ [class.mem]p13: 8812 // If T is the name of a class, then each of the following shall have a 8813 // name different from T: 8814 // - every enumerator of every member of class T that is an enumerated 8815 // type 8816 if (CXXRecordDecl *Record 8817 = dyn_cast<CXXRecordDecl>( 8818 TheEnumDecl->getDeclContext()->getRedeclContext())) 8819 if (Record->getIdentifier() && Record->getIdentifier() == Id) 8820 Diag(IdLoc, diag::err_member_name_of_class) << Id; 8821 8822 EnumConstantDecl *New = 8823 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 8824 8825 if (New) { 8826 // Process attributes. 8827 if (Attr) ProcessDeclAttributeList(S, New, Attr); 8828 8829 // Register this decl in the current scope stack. 8830 New->setAccess(TheEnumDecl->getAccess()); 8831 PushOnScopeChains(New, S); 8832 } 8833 8834 return New; 8835} 8836 8837void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 8838 SourceLocation RBraceLoc, Decl *EnumDeclX, 8839 Decl **Elements, unsigned NumElements, 8840 Scope *S, AttributeList *Attr) { 8841 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 8842 QualType EnumType = Context.getTypeDeclType(Enum); 8843 8844 if (Attr) 8845 ProcessDeclAttributeList(S, Enum, Attr); 8846 8847 if (Enum->isDependentType()) { 8848 for (unsigned i = 0; i != NumElements; ++i) { 8849 EnumConstantDecl *ECD = 8850 cast_or_null<EnumConstantDecl>(Elements[i]); 8851 if (!ECD) continue; 8852 8853 ECD->setType(EnumType); 8854 } 8855 8856 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 8857 return; 8858 } 8859 8860 // TODO: If the result value doesn't fit in an int, it must be a long or long 8861 // long value. ISO C does not support this, but GCC does as an extension, 8862 // emit a warning. 8863 unsigned IntWidth = Context.Target.getIntWidth(); 8864 unsigned CharWidth = Context.Target.getCharWidth(); 8865 unsigned ShortWidth = Context.Target.getShortWidth(); 8866 8867 // Verify that all the values are okay, compute the size of the values, and 8868 // reverse the list. 8869 unsigned NumNegativeBits = 0; 8870 unsigned NumPositiveBits = 0; 8871 8872 // Keep track of whether all elements have type int. 8873 bool AllElementsInt = true; 8874 8875 for (unsigned i = 0; i != NumElements; ++i) { 8876 EnumConstantDecl *ECD = 8877 cast_or_null<EnumConstantDecl>(Elements[i]); 8878 if (!ECD) continue; // Already issued a diagnostic. 8879 8880 const llvm::APSInt &InitVal = ECD->getInitVal(); 8881 8882 // Keep track of the size of positive and negative values. 8883 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 8884 NumPositiveBits = std::max(NumPositiveBits, 8885 (unsigned)InitVal.getActiveBits()); 8886 else 8887 NumNegativeBits = std::max(NumNegativeBits, 8888 (unsigned)InitVal.getMinSignedBits()); 8889 8890 // Keep track of whether every enum element has type int (very commmon). 8891 if (AllElementsInt) 8892 AllElementsInt = ECD->getType() == Context.IntTy; 8893 } 8894 8895 // Figure out the type that should be used for this enum. 8896 QualType BestType; 8897 unsigned BestWidth; 8898 8899 // C++0x N3000 [conv.prom]p3: 8900 // An rvalue of an unscoped enumeration type whose underlying 8901 // type is not fixed can be converted to an rvalue of the first 8902 // of the following types that can represent all the values of 8903 // the enumeration: int, unsigned int, long int, unsigned long 8904 // int, long long int, or unsigned long long int. 8905 // C99 6.4.4.3p2: 8906 // An identifier declared as an enumeration constant has type int. 8907 // The C99 rule is modified by a gcc extension 8908 QualType BestPromotionType; 8909 8910 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 8911 // -fshort-enums is the equivalent to specifying the packed attribute on all 8912 // enum definitions. 8913 if (LangOpts.ShortEnums) 8914 Packed = true; 8915 8916 if (Enum->isFixed()) { 8917 BestType = BestPromotionType = Enum->getIntegerType(); 8918 // We don't need to set BestWidth, because BestType is going to be the type 8919 // of the enumerators, but we do anyway because otherwise some compilers 8920 // warn that it might be used uninitialized. 8921 BestWidth = CharWidth; 8922 } 8923 else if (NumNegativeBits) { 8924 // If there is a negative value, figure out the smallest integer type (of 8925 // int/long/longlong) that fits. 8926 // If it's packed, check also if it fits a char or a short. 8927 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 8928 BestType = Context.SignedCharTy; 8929 BestWidth = CharWidth; 8930 } else if (Packed && NumNegativeBits <= ShortWidth && 8931 NumPositiveBits < ShortWidth) { 8932 BestType = Context.ShortTy; 8933 BestWidth = ShortWidth; 8934 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 8935 BestType = Context.IntTy; 8936 BestWidth = IntWidth; 8937 } else { 8938 BestWidth = Context.Target.getLongWidth(); 8939 8940 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 8941 BestType = Context.LongTy; 8942 } else { 8943 BestWidth = Context.Target.getLongLongWidth(); 8944 8945 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 8946 Diag(Enum->getLocation(), diag::warn_enum_too_large); 8947 BestType = Context.LongLongTy; 8948 } 8949 } 8950 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 8951 } else { 8952 // If there is no negative value, figure out the smallest type that fits 8953 // all of the enumerator values. 8954 // If it's packed, check also if it fits a char or a short. 8955 if (Packed && NumPositiveBits <= CharWidth) { 8956 BestType = Context.UnsignedCharTy; 8957 BestPromotionType = Context.IntTy; 8958 BestWidth = CharWidth; 8959 } else if (Packed && NumPositiveBits <= ShortWidth) { 8960 BestType = Context.UnsignedShortTy; 8961 BestPromotionType = Context.IntTy; 8962 BestWidth = ShortWidth; 8963 } else if (NumPositiveBits <= IntWidth) { 8964 BestType = Context.UnsignedIntTy; 8965 BestWidth = IntWidth; 8966 BestPromotionType 8967 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8968 ? Context.UnsignedIntTy : Context.IntTy; 8969 } else if (NumPositiveBits <= 8970 (BestWidth = Context.Target.getLongWidth())) { 8971 BestType = Context.UnsignedLongTy; 8972 BestPromotionType 8973 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8974 ? Context.UnsignedLongTy : Context.LongTy; 8975 } else { 8976 BestWidth = Context.Target.getLongLongWidth(); 8977 assert(NumPositiveBits <= BestWidth && 8978 "How could an initializer get larger than ULL?"); 8979 BestType = Context.UnsignedLongLongTy; 8980 BestPromotionType 8981 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8982 ? Context.UnsignedLongLongTy : Context.LongLongTy; 8983 } 8984 } 8985 8986 // Loop over all of the enumerator constants, changing their types to match 8987 // the type of the enum if needed. 8988 for (unsigned i = 0; i != NumElements; ++i) { 8989 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 8990 if (!ECD) continue; // Already issued a diagnostic. 8991 8992 // Standard C says the enumerators have int type, but we allow, as an 8993 // extension, the enumerators to be larger than int size. If each 8994 // enumerator value fits in an int, type it as an int, otherwise type it the 8995 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 8996 // that X has type 'int', not 'unsigned'. 8997 8998 // Determine whether the value fits into an int. 8999 llvm::APSInt InitVal = ECD->getInitVal(); 9000 9001 // If it fits into an integer type, force it. Otherwise force it to match 9002 // the enum decl type. 9003 QualType NewTy; 9004 unsigned NewWidth; 9005 bool NewSign; 9006 if (!getLangOptions().CPlusPlus && 9007 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 9008 NewTy = Context.IntTy; 9009 NewWidth = IntWidth; 9010 NewSign = true; 9011 } else if (ECD->getType() == BestType) { 9012 // Already the right type! 9013 if (getLangOptions().CPlusPlus) 9014 // C++ [dcl.enum]p4: Following the closing brace of an 9015 // enum-specifier, each enumerator has the type of its 9016 // enumeration. 9017 ECD->setType(EnumType); 9018 continue; 9019 } else { 9020 NewTy = BestType; 9021 NewWidth = BestWidth; 9022 NewSign = BestType->isSignedIntegerOrEnumerationType(); 9023 } 9024 9025 // Adjust the APSInt value. 9026 InitVal = InitVal.extOrTrunc(NewWidth); 9027 InitVal.setIsSigned(NewSign); 9028 ECD->setInitVal(InitVal); 9029 9030 // Adjust the Expr initializer and type. 9031 if (ECD->getInitExpr() && 9032 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 9033 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 9034 CK_IntegralCast, 9035 ECD->getInitExpr(), 9036 /*base paths*/ 0, 9037 VK_RValue)); 9038 if (getLangOptions().CPlusPlus) 9039 // C++ [dcl.enum]p4: Following the closing brace of an 9040 // enum-specifier, each enumerator has the type of its 9041 // enumeration. 9042 ECD->setType(EnumType); 9043 else 9044 ECD->setType(NewTy); 9045 } 9046 9047 Enum->completeDefinition(BestType, BestPromotionType, 9048 NumPositiveBits, NumNegativeBits); 9049} 9050 9051Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 9052 SourceLocation StartLoc, 9053 SourceLocation EndLoc) { 9054 StringLiteral *AsmString = cast<StringLiteral>(expr); 9055 9056 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 9057 AsmString, StartLoc, 9058 EndLoc); 9059 CurContext->addDecl(New); 9060 return New; 9061} 9062 9063void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 9064 SourceLocation PragmaLoc, 9065 SourceLocation NameLoc) { 9066 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 9067 9068 if (PrevDecl) { 9069 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 9070 } else { 9071 (void)WeakUndeclaredIdentifiers.insert( 9072 std::pair<IdentifierInfo*,WeakInfo> 9073 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 9074 } 9075} 9076 9077void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 9078 IdentifierInfo* AliasName, 9079 SourceLocation PragmaLoc, 9080 SourceLocation NameLoc, 9081 SourceLocation AliasNameLoc) { 9082 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 9083 LookupOrdinaryName); 9084 WeakInfo W = WeakInfo(Name, NameLoc); 9085 9086 if (PrevDecl) { 9087 if (!PrevDecl->hasAttr<AliasAttr>()) 9088 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 9089 DeclApplyPragmaWeak(TUScope, ND, W); 9090 } else { 9091 (void)WeakUndeclaredIdentifiers.insert( 9092 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 9093 } 9094} 9095