SemaDecl.cpp revision c01a9412aa2701d5582f2c3c6e4787bb0a0c37e6
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/Sema.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, 91 // so build a dependent node to describe the type. 92 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), II, 94 SourceLocation(), SS->getRange(), NameLoc 95 ).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && 102 RequireCompleteDeclContext(*SS, LookupCtx)) 103 return 0; 104 } 105 106 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 107 // lookup for class-names. 108 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 109 LookupOrdinaryName; 110 LookupResult Result(*this, &II, NameLoc, Kind); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::NotFoundInCurrentInstantiation: 136 case LookupResult::FoundOverloaded: 137 case LookupResult::FoundUnresolvedValue: 138 Result.suppressDiagnostics(); 139 return 0; 140 141 case LookupResult::Ambiguous: 142 // Recover from type-hiding ambiguities by hiding the type. We'll 143 // do the lookup again when looking for an object, and we can 144 // diagnose the error then. If we don't do this, then the error 145 // about hiding the type will be immediately followed by an error 146 // that only makes sense if the identifier was treated like a type. 147 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 148 Result.suppressDiagnostics(); 149 return 0; 150 } 151 152 // Look to see if we have a type anywhere in the list of results. 153 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 154 Res != ResEnd; ++Res) { 155 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 156 if (!IIDecl || 157 (*Res)->getLocation().getRawEncoding() < 158 IIDecl->getLocation().getRawEncoding()) 159 IIDecl = *Res; 160 } 161 } 162 163 if (!IIDecl) { 164 // None of the entities we found is a type, so there is no way 165 // to even assume that the result is a type. In this case, don't 166 // complain about the ambiguity. The parser will either try to 167 // perform this lookup again (e.g., as an object name), which 168 // will produce the ambiguity, or will complain that it expected 169 // a type name. 170 Result.suppressDiagnostics(); 171 return 0; 172 } 173 174 // We found a type within the ambiguous lookup; diagnose the 175 // ambiguity and then return that type. This might be the right 176 // answer, or it might not be, but it suppresses any attempt to 177 // perform the name lookup again. 178 break; 179 180 case LookupResult::Found: 181 IIDecl = Result.getFoundDecl(); 182 break; 183 } 184 185 assert(IIDecl && "Didn't find decl"); 186 187 QualType T; 188 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 189 DiagnoseUseOfDecl(IIDecl, NameLoc); 190 191 if (T.isNull()) 192 T = Context.getTypeDeclType(TD); 193 194 if (SS) 195 T = getElaboratedType(ETK_None, *SS, T); 196 197 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 198 T = Context.getObjCInterfaceType(IDecl); 199 } else { 200 // If it's not plausibly a type, suppress diagnostics. 201 Result.suppressDiagnostics(); 202 return 0; 203 } 204 205 return T.getAsOpaquePtr(); 206} 207 208/// isTagName() - This method is called *for error recovery purposes only* 209/// to determine if the specified name is a valid tag name ("struct foo"). If 210/// so, this returns the TST for the tag corresponding to it (TST_enum, 211/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 212/// where the user forgot to specify the tag. 213DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 214 // Do a tag name lookup in this scope. 215 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 216 LookupName(R, S, false); 217 R.suppressDiagnostics(); 218 if (R.getResultKind() == LookupResult::Found) 219 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 220 switch (TD->getTagKind()) { 221 default: return DeclSpec::TST_unspecified; 222 case TTK_Struct: return DeclSpec::TST_struct; 223 case TTK_Union: return DeclSpec::TST_union; 224 case TTK_Class: return DeclSpec::TST_class; 225 case TTK_Enum: return DeclSpec::TST_enum; 226 } 227 } 228 229 return DeclSpec::TST_unspecified; 230} 231 232bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 233 SourceLocation IILoc, 234 Scope *S, 235 CXXScopeSpec *SS, 236 TypeTy *&SuggestedType) { 237 // We don't have anything to suggest (yet). 238 SuggestedType = 0; 239 240 // There may have been a typo in the name of the type. Look up typo 241 // results, in case we have something that we can suggest. 242 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 243 NotForRedeclaration); 244 245 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 246 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 247 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 248 !Result->isInvalidDecl()) { 249 // We found a similarly-named type or interface; suggest that. 250 if (!SS || !SS->isSet()) 251 Diag(IILoc, diag::err_unknown_typename_suggest) 252 << &II << Lookup.getLookupName() 253 << FixItHint::CreateReplacement(SourceRange(IILoc), 254 Result->getNameAsString()); 255 else if (DeclContext *DC = computeDeclContext(*SS, false)) 256 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 257 << &II << DC << Lookup.getLookupName() << SS->getRange() 258 << FixItHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else 261 llvm_unreachable("could not have corrected a typo here"); 262 263 Diag(Result->getLocation(), diag::note_previous_decl) 264 << Result->getDeclName(); 265 266 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 267 return true; 268 } 269 } else if (Lookup.empty()) { 270 // We corrected to a keyword. 271 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Corrected; 274 return true; 275 } 276 } 277 278 if (getLangOptions().CPlusPlus) { 279 // See if II is a class template that the user forgot to pass arguments to. 280 UnqualifiedId Name; 281 Name.setIdentifier(&II, IILoc); 282 CXXScopeSpec EmptySS; 283 TemplateTy TemplateResult; 284 bool MemberOfUnknownSpecialization; 285 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 286 Name, 0, true, TemplateResult, 287 MemberOfUnknownSpecialization) == TNK_Type_template) { 288 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 289 Diag(IILoc, diag::err_template_missing_args) << TplName; 290 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 291 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 292 << TplDecl->getTemplateParameters()->getSourceRange(); 293 } 294 return true; 295 } 296 } 297 298 // FIXME: Should we move the logic that tries to recover from a missing tag 299 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 300 301 if (!SS || (!SS->isSet() && !SS->isInvalid())) 302 Diag(IILoc, diag::err_unknown_typename) << &II; 303 else if (DeclContext *DC = computeDeclContext(*SS, false)) 304 Diag(IILoc, diag::err_typename_nested_not_found) 305 << &II << DC << SS->getRange(); 306 else if (isDependentScopeSpecifier(*SS)) { 307 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 308 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 309 << SourceRange(SS->getRange().getBegin(), IILoc) 310 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 311 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 312 } else { 313 assert(SS && SS->isInvalid() && 314 "Invalid scope specifier has already been diagnosed"); 315 } 316 317 return true; 318} 319 320// Determines the context to return to after temporarily entering a 321// context. This depends in an unnecessarily complicated way on the 322// exact ordering of callbacks from the parser. 323DeclContext *Sema::getContainingDC(DeclContext *DC) { 324 325 // Functions defined inline within classes aren't parsed until we've 326 // finished parsing the top-level class, so the top-level class is 327 // the context we'll need to return to. 328 if (isa<FunctionDecl>(DC)) { 329 DC = DC->getLexicalParent(); 330 331 // A function not defined within a class will always return to its 332 // lexical context. 333 if (!isa<CXXRecordDecl>(DC)) 334 return DC; 335 336 // A C++ inline method/friend is parsed *after* the topmost class 337 // it was declared in is fully parsed ("complete"); the topmost 338 // class is the context we need to return to. 339 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 340 DC = RD; 341 342 // Return the declaration context of the topmost class the inline method is 343 // declared in. 344 return DC; 345 } 346 347 // ObjCMethodDecls are parsed (for some reason) outside the context 348 // of the class. 349 if (isa<ObjCMethodDecl>(DC)) 350 return DC->getLexicalParent()->getLexicalParent(); 351 352 return DC->getLexicalParent(); 353} 354 355void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 356 assert(getContainingDC(DC) == CurContext && 357 "The next DeclContext should be lexically contained in the current one."); 358 CurContext = DC; 359 S->setEntity(DC); 360} 361 362void Sema::PopDeclContext() { 363 assert(CurContext && "DeclContext imbalance!"); 364 365 CurContext = getContainingDC(CurContext); 366 assert(CurContext && "Popped translation unit!"); 367} 368 369/// EnterDeclaratorContext - Used when we must lookup names in the context 370/// of a declarator's nested name specifier. 371/// 372void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 373 // C++0x [basic.lookup.unqual]p13: 374 // A name used in the definition of a static data member of class 375 // X (after the qualified-id of the static member) is looked up as 376 // if the name was used in a member function of X. 377 // C++0x [basic.lookup.unqual]p14: 378 // If a variable member of a namespace is defined outside of the 379 // scope of its namespace then any name used in the definition of 380 // the variable member (after the declarator-id) is looked up as 381 // if the definition of the variable member occurred in its 382 // namespace. 383 // Both of these imply that we should push a scope whose context 384 // is the semantic context of the declaration. We can't use 385 // PushDeclContext here because that context is not necessarily 386 // lexically contained in the current context. Fortunately, 387 // the containing scope should have the appropriate information. 388 389 assert(!S->getEntity() && "scope already has entity"); 390 391#ifndef NDEBUG 392 Scope *Ancestor = S->getParent(); 393 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 394 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 395#endif 396 397 CurContext = DC; 398 S->setEntity(DC); 399} 400 401void Sema::ExitDeclaratorContext(Scope *S) { 402 assert(S->getEntity() == CurContext && "Context imbalance!"); 403 404 // Switch back to the lexical context. The safety of this is 405 // enforced by an assert in EnterDeclaratorContext. 406 Scope *Ancestor = S->getParent(); 407 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 408 CurContext = (DeclContext*) Ancestor->getEntity(); 409 410 // We don't need to do anything with the scope, which is going to 411 // disappear. 412} 413 414/// \brief Determine whether we allow overloading of the function 415/// PrevDecl with another declaration. 416/// 417/// This routine determines whether overloading is possible, not 418/// whether some new function is actually an overload. It will return 419/// true in C++ (where we can always provide overloads) or, as an 420/// extension, in C when the previous function is already an 421/// overloaded function declaration or has the "overloadable" 422/// attribute. 423static bool AllowOverloadingOfFunction(LookupResult &Previous, 424 ASTContext &Context) { 425 if (Context.getLangOptions().CPlusPlus) 426 return true; 427 428 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 429 return true; 430 431 return (Previous.getResultKind() == LookupResult::Found 432 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 433} 434 435/// Add this decl to the scope shadowed decl chains. 436void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 437 // Move up the scope chain until we find the nearest enclosing 438 // non-transparent context. The declaration will be introduced into this 439 // scope. 440 while (S->getEntity() && 441 ((DeclContext *)S->getEntity())->isTransparentContext()) 442 S = S->getParent(); 443 444 // Add scoped declarations into their context, so that they can be 445 // found later. Declarations without a context won't be inserted 446 // into any context. 447 if (AddToContext) 448 CurContext->addDecl(D); 449 450 // Out-of-line definitions shouldn't be pushed into scope in C++. 451 // Out-of-line variable and function definitions shouldn't even in C. 452 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 453 D->isOutOfLine()) 454 return; 455 456 // Template instantiations should also not be pushed into scope. 457 if (isa<FunctionDecl>(D) && 458 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 459 return; 460 461 // If this replaces anything in the current scope, 462 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 463 IEnd = IdResolver.end(); 464 for (; I != IEnd; ++I) { 465 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 466 S->RemoveDecl(DeclPtrTy::make(*I)); 467 IdResolver.RemoveDecl(*I); 468 469 // Should only need to replace one decl. 470 break; 471 } 472 } 473 474 S->AddDecl(DeclPtrTy::make(D)); 475 IdResolver.AddDecl(D); 476} 477 478bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 479 return IdResolver.isDeclInScope(D, Ctx, Context, S); 480} 481 482static bool isOutOfScopePreviousDeclaration(NamedDecl *, 483 DeclContext*, 484 ASTContext&); 485 486/// Filters out lookup results that don't fall within the given scope 487/// as determined by isDeclInScope. 488static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 489 DeclContext *Ctx, Scope *S, 490 bool ConsiderLinkage) { 491 LookupResult::Filter F = R.makeFilter(); 492 while (F.hasNext()) { 493 NamedDecl *D = F.next(); 494 495 if (SemaRef.isDeclInScope(D, Ctx, S)) 496 continue; 497 498 if (ConsiderLinkage && 499 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 500 continue; 501 502 F.erase(); 503 } 504 505 F.done(); 506} 507 508static bool isUsingDecl(NamedDecl *D) { 509 return isa<UsingShadowDecl>(D) || 510 isa<UnresolvedUsingTypenameDecl>(D) || 511 isa<UnresolvedUsingValueDecl>(D); 512} 513 514/// Removes using shadow declarations from the lookup results. 515static void RemoveUsingDecls(LookupResult &R) { 516 LookupResult::Filter F = R.makeFilter(); 517 while (F.hasNext()) 518 if (isUsingDecl(F.next())) 519 F.erase(); 520 521 F.done(); 522} 523 524static bool ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) { 525 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 526 // Warn for static, non-inlined function definitions that 527 // have not been used. 528 // FIXME: Also include static functions declared but not defined. 529 return (!FD->isInvalidDecl() 530 && !FD->isInlined() && FD->getLinkage() == InternalLinkage 531 && !FD->isUsed() && !FD->hasAttr<UnusedAttr>() 532 && !FD->hasAttr<ConstructorAttr>() 533 && !FD->hasAttr<DestructorAttr>()); 534 } 535 536 return false; 537} 538 539void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 540 if (ShouldWarnIfUnusedFileScopedDecl(D)) 541 UnusedFileScopedDecls.push_back(D); 542} 543 544static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 545 if (D->isInvalidDecl()) 546 return false; 547 548 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 549 return false; 550 551 // White-list anything that isn't a local variable. 552 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 553 !D->getDeclContext()->isFunctionOrMethod()) 554 return false; 555 556 // Types of valid local variables should be complete, so this should succeed. 557 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 558 559 // White-list anything with an __attribute__((unused)) type. 560 QualType Ty = VD->getType(); 561 562 // Only look at the outermost level of typedef. 563 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 564 if (TT->getDecl()->hasAttr<UnusedAttr>()) 565 return false; 566 } 567 568 // If we failed to complete the type for some reason, or if the type is 569 // dependent, don't diagnose the variable. 570 if (Ty->isIncompleteType() || Ty->isDependentType()) 571 return false; 572 573 if (const TagType *TT = Ty->getAs<TagType>()) { 574 const TagDecl *Tag = TT->getDecl(); 575 if (Tag->hasAttr<UnusedAttr>()) 576 return false; 577 578 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 579 // FIXME: Checking for the presence of a user-declared constructor 580 // isn't completely accurate; we'd prefer to check that the initializer 581 // has no side effects. 582 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 583 return false; 584 } 585 } 586 587 // TODO: __attribute__((unused)) templates? 588 } 589 590 return true; 591} 592 593void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 594 if (!ShouldDiagnoseUnusedDecl(D)) 595 return; 596 597 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 598 Diag(D->getLocation(), diag::warn_unused_exception_param) 599 << D->getDeclName(); 600 else 601 Diag(D->getLocation(), diag::warn_unused_variable) 602 << D->getDeclName(); 603} 604 605void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 606 if (S->decl_empty()) return; 607 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 608 "Scope shouldn't contain decls!"); 609 610 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 611 I != E; ++I) { 612 Decl *TmpD = (*I).getAs<Decl>(); 613 assert(TmpD && "This decl didn't get pushed??"); 614 615 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 616 NamedDecl *D = cast<NamedDecl>(TmpD); 617 618 if (!D->getDeclName()) continue; 619 620 // Diagnose unused variables in this scope. 621 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 622 DiagnoseUnusedDecl(D); 623 624 // Remove this name from our lexical scope. 625 IdResolver.RemoveDecl(D); 626 } 627} 628 629/// \brief Look for an Objective-C class in the translation unit. 630/// 631/// \param Id The name of the Objective-C class we're looking for. If 632/// typo-correction fixes this name, the Id will be updated 633/// to the fixed name. 634/// 635/// \param IdLoc The location of the name in the translation unit. 636/// 637/// \param TypoCorrection If true, this routine will attempt typo correction 638/// if there is no class with the given name. 639/// 640/// \returns The declaration of the named Objective-C class, or NULL if the 641/// class could not be found. 642ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 643 SourceLocation IdLoc, 644 bool TypoCorrection) { 645 // The third "scope" argument is 0 since we aren't enabling lazy built-in 646 // creation from this context. 647 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 648 649 if (!IDecl && TypoCorrection) { 650 // Perform typo correction at the given location, but only if we 651 // find an Objective-C class name. 652 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 653 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 654 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 655 Diag(IdLoc, diag::err_undef_interface_suggest) 656 << Id << IDecl->getDeclName() 657 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 658 Diag(IDecl->getLocation(), diag::note_previous_decl) 659 << IDecl->getDeclName(); 660 661 Id = IDecl->getIdentifier(); 662 } 663 } 664 665 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 666} 667 668/// getNonFieldDeclScope - Retrieves the innermost scope, starting 669/// from S, where a non-field would be declared. This routine copes 670/// with the difference between C and C++ scoping rules in structs and 671/// unions. For example, the following code is well-formed in C but 672/// ill-formed in C++: 673/// @code 674/// struct S6 { 675/// enum { BAR } e; 676/// }; 677/// 678/// void test_S6() { 679/// struct S6 a; 680/// a.e = BAR; 681/// } 682/// @endcode 683/// For the declaration of BAR, this routine will return a different 684/// scope. The scope S will be the scope of the unnamed enumeration 685/// within S6. In C++, this routine will return the scope associated 686/// with S6, because the enumeration's scope is a transparent 687/// context but structures can contain non-field names. In C, this 688/// routine will return the translation unit scope, since the 689/// enumeration's scope is a transparent context and structures cannot 690/// contain non-field names. 691Scope *Sema::getNonFieldDeclScope(Scope *S) { 692 while (((S->getFlags() & Scope::DeclScope) == 0) || 693 (S->getEntity() && 694 ((DeclContext *)S->getEntity())->isTransparentContext()) || 695 (S->isClassScope() && !getLangOptions().CPlusPlus)) 696 S = S->getParent(); 697 return S; 698} 699 700void Sema::InitBuiltinVaListType() { 701 if (!Context.getBuiltinVaListType().isNull()) 702 return; 703 704 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 705 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 706 LookupOrdinaryName, ForRedeclaration); 707 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 708 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 709} 710 711/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 712/// file scope. lazily create a decl for it. ForRedeclaration is true 713/// if we're creating this built-in in anticipation of redeclaring the 714/// built-in. 715NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 716 Scope *S, bool ForRedeclaration, 717 SourceLocation Loc) { 718 Builtin::ID BID = (Builtin::ID)bid; 719 720 if (Context.BuiltinInfo.hasVAListUse(BID)) 721 InitBuiltinVaListType(); 722 723 ASTContext::GetBuiltinTypeError Error; 724 QualType R = Context.GetBuiltinType(BID, Error); 725 switch (Error) { 726 case ASTContext::GE_None: 727 // Okay 728 break; 729 730 case ASTContext::GE_Missing_stdio: 731 if (ForRedeclaration) 732 Diag(Loc, diag::err_implicit_decl_requires_stdio) 733 << Context.BuiltinInfo.GetName(BID); 734 return 0; 735 736 case ASTContext::GE_Missing_setjmp: 737 if (ForRedeclaration) 738 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 739 << Context.BuiltinInfo.GetName(BID); 740 return 0; 741 } 742 743 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 744 Diag(Loc, diag::ext_implicit_lib_function_decl) 745 << Context.BuiltinInfo.GetName(BID) 746 << R; 747 if (Context.BuiltinInfo.getHeaderName(BID) && 748 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 749 != Diagnostic::Ignored) 750 Diag(Loc, diag::note_please_include_header) 751 << Context.BuiltinInfo.getHeaderName(BID) 752 << Context.BuiltinInfo.GetName(BID); 753 } 754 755 FunctionDecl *New = FunctionDecl::Create(Context, 756 Context.getTranslationUnitDecl(), 757 Loc, II, R, /*TInfo=*/0, 758 FunctionDecl::Extern, 759 FunctionDecl::None, false, 760 /*hasPrototype=*/true); 761 New->setImplicit(); 762 763 // Create Decl objects for each parameter, adding them to the 764 // FunctionDecl. 765 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 766 llvm::SmallVector<ParmVarDecl*, 16> Params; 767 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 768 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 769 FT->getArgType(i), /*TInfo=*/0, 770 VarDecl::None, VarDecl::None, 0)); 771 New->setParams(Params.data(), Params.size()); 772 } 773 774 AddKnownFunctionAttributes(New); 775 776 // TUScope is the translation-unit scope to insert this function into. 777 // FIXME: This is hideous. We need to teach PushOnScopeChains to 778 // relate Scopes to DeclContexts, and probably eliminate CurContext 779 // entirely, but we're not there yet. 780 DeclContext *SavedContext = CurContext; 781 CurContext = Context.getTranslationUnitDecl(); 782 PushOnScopeChains(New, TUScope); 783 CurContext = SavedContext; 784 return New; 785} 786 787/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 788/// same name and scope as a previous declaration 'Old'. Figure out 789/// how to resolve this situation, merging decls or emitting 790/// diagnostics as appropriate. If there was an error, set New to be invalid. 791/// 792void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 793 // If the new decl is known invalid already, don't bother doing any 794 // merging checks. 795 if (New->isInvalidDecl()) return; 796 797 // Allow multiple definitions for ObjC built-in typedefs. 798 // FIXME: Verify the underlying types are equivalent! 799 if (getLangOptions().ObjC1) { 800 const IdentifierInfo *TypeID = New->getIdentifier(); 801 switch (TypeID->getLength()) { 802 default: break; 803 case 2: 804 if (!TypeID->isStr("id")) 805 break; 806 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 807 // Install the built-in type for 'id', ignoring the current definition. 808 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 809 return; 810 case 5: 811 if (!TypeID->isStr("Class")) 812 break; 813 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 814 // Install the built-in type for 'Class', ignoring the current definition. 815 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 816 return; 817 case 3: 818 if (!TypeID->isStr("SEL")) 819 break; 820 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 821 // Install the built-in type for 'SEL', ignoring the current definition. 822 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 823 return; 824 case 8: 825 if (!TypeID->isStr("Protocol")) 826 break; 827 Context.setObjCProtoType(New->getUnderlyingType()); 828 return; 829 } 830 // Fall through - the typedef name was not a builtin type. 831 } 832 833 // Verify the old decl was also a type. 834 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 835 if (!Old) { 836 Diag(New->getLocation(), diag::err_redefinition_different_kind) 837 << New->getDeclName(); 838 839 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 840 if (OldD->getLocation().isValid()) 841 Diag(OldD->getLocation(), diag::note_previous_definition); 842 843 return New->setInvalidDecl(); 844 } 845 846 // If the old declaration is invalid, just give up here. 847 if (Old->isInvalidDecl()) 848 return New->setInvalidDecl(); 849 850 // Determine the "old" type we'll use for checking and diagnostics. 851 QualType OldType; 852 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 853 OldType = OldTypedef->getUnderlyingType(); 854 else 855 OldType = Context.getTypeDeclType(Old); 856 857 // If the typedef types are not identical, reject them in all languages and 858 // with any extensions enabled. 859 860 if (OldType != New->getUnderlyingType() && 861 Context.getCanonicalType(OldType) != 862 Context.getCanonicalType(New->getUnderlyingType())) { 863 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 864 << New->getUnderlyingType() << OldType; 865 if (Old->getLocation().isValid()) 866 Diag(Old->getLocation(), diag::note_previous_definition); 867 return New->setInvalidDecl(); 868 } 869 870 // The types match. Link up the redeclaration chain if the old 871 // declaration was a typedef. 872 // FIXME: this is a potential source of wierdness if the type 873 // spellings don't match exactly. 874 if (isa<TypedefDecl>(Old)) 875 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 876 877 if (getLangOptions().Microsoft) 878 return; 879 880 if (getLangOptions().CPlusPlus) { 881 // C++ [dcl.typedef]p2: 882 // In a given non-class scope, a typedef specifier can be used to 883 // redefine the name of any type declared in that scope to refer 884 // to the type to which it already refers. 885 if (!isa<CXXRecordDecl>(CurContext)) 886 return; 887 888 // C++0x [dcl.typedef]p4: 889 // In a given class scope, a typedef specifier can be used to redefine 890 // any class-name declared in that scope that is not also a typedef-name 891 // to refer to the type to which it already refers. 892 // 893 // This wording came in via DR424, which was a correction to the 894 // wording in DR56, which accidentally banned code like: 895 // 896 // struct S { 897 // typedef struct A { } A; 898 // }; 899 // 900 // in the C++03 standard. We implement the C++0x semantics, which 901 // allow the above but disallow 902 // 903 // struct S { 904 // typedef int I; 905 // typedef int I; 906 // }; 907 // 908 // since that was the intent of DR56. 909 if (!isa<TypedefDecl >(Old)) 910 return; 911 912 Diag(New->getLocation(), diag::err_redefinition) 913 << New->getDeclName(); 914 Diag(Old->getLocation(), diag::note_previous_definition); 915 return New->setInvalidDecl(); 916 } 917 918 // If we have a redefinition of a typedef in C, emit a warning. This warning 919 // is normally mapped to an error, but can be controlled with 920 // -Wtypedef-redefinition. If either the original or the redefinition is 921 // in a system header, don't emit this for compatibility with GCC. 922 if (getDiagnostics().getSuppressSystemWarnings() && 923 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 924 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 925 return; 926 927 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 928 << New->getDeclName(); 929 Diag(Old->getLocation(), diag::note_previous_definition); 930 return; 931} 932 933/// DeclhasAttr - returns true if decl Declaration already has the target 934/// attribute. 935static bool 936DeclHasAttr(const Decl *decl, const Attr *target) { 937 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 938 if (attr->getKind() == target->getKind()) 939 return true; 940 941 return false; 942} 943 944/// MergeAttributes - append attributes from the Old decl to the New one. 945static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 946 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 947 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 948 Attr *NewAttr = attr->clone(C); 949 NewAttr->setInherited(true); 950 New->addAttr(NewAttr); 951 } 952 } 953} 954 955namespace { 956 957/// Used in MergeFunctionDecl to keep track of function parameters in 958/// C. 959struct GNUCompatibleParamWarning { 960 ParmVarDecl *OldParm; 961 ParmVarDecl *NewParm; 962 QualType PromotedType; 963}; 964 965} 966 967/// getSpecialMember - get the special member enum for a method. 968Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 969 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 970 if (Ctor->isCopyConstructor()) 971 return Sema::CXXCopyConstructor; 972 973 return Sema::CXXConstructor; 974 } 975 976 if (isa<CXXDestructorDecl>(MD)) 977 return Sema::CXXDestructor; 978 979 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 980 return Sema::CXXCopyAssignment; 981} 982 983/// canRedefineFunction - checks if a function can be redefined. Currently, 984/// only extern inline functions can be redefined, and even then only in 985/// GNU89 mode. 986static bool canRedefineFunction(const FunctionDecl *FD, 987 const LangOptions& LangOpts) { 988 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 989 FD->isInlineSpecified() && 990 FD->getStorageClass() == FunctionDecl::Extern); 991} 992 993/// MergeFunctionDecl - We just parsed a function 'New' from 994/// declarator D which has the same name and scope as a previous 995/// declaration 'Old'. Figure out how to resolve this situation, 996/// merging decls or emitting diagnostics as appropriate. 997/// 998/// In C++, New and Old must be declarations that are not 999/// overloaded. Use IsOverload to determine whether New and Old are 1000/// overloaded, and to select the Old declaration that New should be 1001/// merged with. 1002/// 1003/// Returns true if there was an error, false otherwise. 1004bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1005 // Verify the old decl was also a function. 1006 FunctionDecl *Old = 0; 1007 if (FunctionTemplateDecl *OldFunctionTemplate 1008 = dyn_cast<FunctionTemplateDecl>(OldD)) 1009 Old = OldFunctionTemplate->getTemplatedDecl(); 1010 else 1011 Old = dyn_cast<FunctionDecl>(OldD); 1012 if (!Old) { 1013 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1014 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1015 Diag(Shadow->getTargetDecl()->getLocation(), 1016 diag::note_using_decl_target); 1017 Diag(Shadow->getUsingDecl()->getLocation(), 1018 diag::note_using_decl) << 0; 1019 return true; 1020 } 1021 1022 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1023 << New->getDeclName(); 1024 Diag(OldD->getLocation(), diag::note_previous_definition); 1025 return true; 1026 } 1027 1028 // Determine whether the previous declaration was a definition, 1029 // implicit declaration, or a declaration. 1030 diag::kind PrevDiag; 1031 if (Old->isThisDeclarationADefinition()) 1032 PrevDiag = diag::note_previous_definition; 1033 else if (Old->isImplicit()) 1034 PrevDiag = diag::note_previous_implicit_declaration; 1035 else 1036 PrevDiag = diag::note_previous_declaration; 1037 1038 QualType OldQType = Context.getCanonicalType(Old->getType()); 1039 QualType NewQType = Context.getCanonicalType(New->getType()); 1040 1041 // Don't complain about this if we're in GNU89 mode and the old function 1042 // is an extern inline function. 1043 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1044 New->getStorageClass() == FunctionDecl::Static && 1045 Old->getStorageClass() != FunctionDecl::Static && 1046 !canRedefineFunction(Old, getLangOptions())) { 1047 Diag(New->getLocation(), diag::err_static_non_static) 1048 << New; 1049 Diag(Old->getLocation(), PrevDiag); 1050 return true; 1051 } 1052 1053 // If a function is first declared with a calling convention, but is 1054 // later declared or defined without one, the second decl assumes the 1055 // calling convention of the first. 1056 // 1057 // For the new decl, we have to look at the NON-canonical type to tell the 1058 // difference between a function that really doesn't have a calling 1059 // convention and one that is declared cdecl. That's because in 1060 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1061 // because it is the default calling convention. 1062 // 1063 // Note also that we DO NOT return at this point, because we still have 1064 // other tests to run. 1065 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1066 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1067 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1068 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1069 if (OldTypeInfo.getCC() != CC_Default && 1070 NewTypeInfo.getCC() == CC_Default) { 1071 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1072 New->setType(NewQType); 1073 NewQType = Context.getCanonicalType(NewQType); 1074 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1075 NewTypeInfo.getCC())) { 1076 // Calling conventions really aren't compatible, so complain. 1077 Diag(New->getLocation(), diag::err_cconv_change) 1078 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1079 << (OldTypeInfo.getCC() == CC_Default) 1080 << (OldTypeInfo.getCC() == CC_Default ? "" : 1081 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1082 Diag(Old->getLocation(), diag::note_previous_declaration); 1083 return true; 1084 } 1085 1086 // FIXME: diagnose the other way around? 1087 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1088 NewQType = Context.getNoReturnType(NewQType); 1089 New->setType(NewQType); 1090 assert(NewQType.isCanonical()); 1091 } 1092 1093 // Merge regparm attribute. 1094 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1095 if (NewType->getRegParmType()) { 1096 Diag(New->getLocation(), diag::err_regparm_mismatch) 1097 << NewType->getRegParmType() 1098 << OldType->getRegParmType(); 1099 Diag(Old->getLocation(), diag::note_previous_declaration); 1100 return true; 1101 } 1102 1103 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1104 New->setType(NewQType); 1105 assert(NewQType.isCanonical()); 1106 } 1107 1108 if (getLangOptions().CPlusPlus) { 1109 // (C++98 13.1p2): 1110 // Certain function declarations cannot be overloaded: 1111 // -- Function declarations that differ only in the return type 1112 // cannot be overloaded. 1113 QualType OldReturnType 1114 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1115 QualType NewReturnType 1116 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1117 QualType ResQT; 1118 if (OldReturnType != NewReturnType) { 1119 if (NewReturnType->isObjCObjectPointerType() 1120 && OldReturnType->isObjCObjectPointerType()) 1121 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1122 if (ResQT.isNull()) { 1123 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1124 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1125 return true; 1126 } 1127 else 1128 NewQType = ResQT; 1129 } 1130 1131 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1132 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1133 if (OldMethod && NewMethod) { 1134 // Preserve triviality. 1135 NewMethod->setTrivial(OldMethod->isTrivial()); 1136 1137 bool isFriend = NewMethod->getFriendObjectKind(); 1138 1139 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1140 // -- Member function declarations with the same name and the 1141 // same parameter types cannot be overloaded if any of them 1142 // is a static member function declaration. 1143 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1144 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1145 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1146 return true; 1147 } 1148 1149 // C++ [class.mem]p1: 1150 // [...] A member shall not be declared twice in the 1151 // member-specification, except that a nested class or member 1152 // class template can be declared and then later defined. 1153 unsigned NewDiag; 1154 if (isa<CXXConstructorDecl>(OldMethod)) 1155 NewDiag = diag::err_constructor_redeclared; 1156 else if (isa<CXXDestructorDecl>(NewMethod)) 1157 NewDiag = diag::err_destructor_redeclared; 1158 else if (isa<CXXConversionDecl>(NewMethod)) 1159 NewDiag = diag::err_conv_function_redeclared; 1160 else 1161 NewDiag = diag::err_member_redeclared; 1162 1163 Diag(New->getLocation(), NewDiag); 1164 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1165 1166 // Complain if this is an explicit declaration of a special 1167 // member that was initially declared implicitly. 1168 // 1169 // As an exception, it's okay to befriend such methods in order 1170 // to permit the implicit constructor/destructor/operator calls. 1171 } else if (OldMethod->isImplicit()) { 1172 if (isFriend) { 1173 NewMethod->setImplicit(); 1174 } else { 1175 Diag(NewMethod->getLocation(), 1176 diag::err_definition_of_implicitly_declared_member) 1177 << New << getSpecialMember(OldMethod); 1178 return true; 1179 } 1180 } 1181 } 1182 1183 // (C++98 8.3.5p3): 1184 // All declarations for a function shall agree exactly in both the 1185 // return type and the parameter-type-list. 1186 // attributes should be ignored when comparing. 1187 if (Context.getNoReturnType(OldQType, false) == 1188 Context.getNoReturnType(NewQType, false)) 1189 return MergeCompatibleFunctionDecls(New, Old); 1190 1191 // Fall through for conflicting redeclarations and redefinitions. 1192 } 1193 1194 // C: Function types need to be compatible, not identical. This handles 1195 // duplicate function decls like "void f(int); void f(enum X);" properly. 1196 if (!getLangOptions().CPlusPlus && 1197 Context.typesAreCompatible(OldQType, NewQType)) { 1198 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1199 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1200 const FunctionProtoType *OldProto = 0; 1201 if (isa<FunctionNoProtoType>(NewFuncType) && 1202 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1203 // The old declaration provided a function prototype, but the 1204 // new declaration does not. Merge in the prototype. 1205 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1206 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1207 OldProto->arg_type_end()); 1208 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1209 ParamTypes.data(), ParamTypes.size(), 1210 OldProto->isVariadic(), 1211 OldProto->getTypeQuals(), 1212 false, false, 0, 0, 1213 OldProto->getExtInfo()); 1214 New->setType(NewQType); 1215 New->setHasInheritedPrototype(); 1216 1217 // Synthesize a parameter for each argument type. 1218 llvm::SmallVector<ParmVarDecl*, 16> Params; 1219 for (FunctionProtoType::arg_type_iterator 1220 ParamType = OldProto->arg_type_begin(), 1221 ParamEnd = OldProto->arg_type_end(); 1222 ParamType != ParamEnd; ++ParamType) { 1223 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1224 SourceLocation(), 0, 1225 *ParamType, /*TInfo=*/0, 1226 VarDecl::None, VarDecl::None, 1227 0); 1228 Param->setImplicit(); 1229 Params.push_back(Param); 1230 } 1231 1232 New->setParams(Params.data(), Params.size()); 1233 } 1234 1235 return MergeCompatibleFunctionDecls(New, Old); 1236 } 1237 1238 // GNU C permits a K&R definition to follow a prototype declaration 1239 // if the declared types of the parameters in the K&R definition 1240 // match the types in the prototype declaration, even when the 1241 // promoted types of the parameters from the K&R definition differ 1242 // from the types in the prototype. GCC then keeps the types from 1243 // the prototype. 1244 // 1245 // If a variadic prototype is followed by a non-variadic K&R definition, 1246 // the K&R definition becomes variadic. This is sort of an edge case, but 1247 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1248 // C99 6.9.1p8. 1249 if (!getLangOptions().CPlusPlus && 1250 Old->hasPrototype() && !New->hasPrototype() && 1251 New->getType()->getAs<FunctionProtoType>() && 1252 Old->getNumParams() == New->getNumParams()) { 1253 llvm::SmallVector<QualType, 16> ArgTypes; 1254 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1255 const FunctionProtoType *OldProto 1256 = Old->getType()->getAs<FunctionProtoType>(); 1257 const FunctionProtoType *NewProto 1258 = New->getType()->getAs<FunctionProtoType>(); 1259 1260 // Determine whether this is the GNU C extension. 1261 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1262 NewProto->getResultType()); 1263 bool LooseCompatible = !MergedReturn.isNull(); 1264 for (unsigned Idx = 0, End = Old->getNumParams(); 1265 LooseCompatible && Idx != End; ++Idx) { 1266 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1267 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1268 if (Context.typesAreCompatible(OldParm->getType(), 1269 NewProto->getArgType(Idx))) { 1270 ArgTypes.push_back(NewParm->getType()); 1271 } else if (Context.typesAreCompatible(OldParm->getType(), 1272 NewParm->getType(), 1273 /*CompareUnqualified=*/true)) { 1274 GNUCompatibleParamWarning Warn 1275 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1276 Warnings.push_back(Warn); 1277 ArgTypes.push_back(NewParm->getType()); 1278 } else 1279 LooseCompatible = false; 1280 } 1281 1282 if (LooseCompatible) { 1283 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1284 Diag(Warnings[Warn].NewParm->getLocation(), 1285 diag::ext_param_promoted_not_compatible_with_prototype) 1286 << Warnings[Warn].PromotedType 1287 << Warnings[Warn].OldParm->getType(); 1288 if (Warnings[Warn].OldParm->getLocation().isValid()) 1289 Diag(Warnings[Warn].OldParm->getLocation(), 1290 diag::note_previous_declaration); 1291 } 1292 1293 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1294 ArgTypes.size(), 1295 OldProto->isVariadic(), 0, 1296 false, false, 0, 0, 1297 OldProto->getExtInfo())); 1298 return MergeCompatibleFunctionDecls(New, Old); 1299 } 1300 1301 // Fall through to diagnose conflicting types. 1302 } 1303 1304 // A function that has already been declared has been redeclared or defined 1305 // with a different type- show appropriate diagnostic 1306 if (unsigned BuiltinID = Old->getBuiltinID()) { 1307 // The user has declared a builtin function with an incompatible 1308 // signature. 1309 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1310 // The function the user is redeclaring is a library-defined 1311 // function like 'malloc' or 'printf'. Warn about the 1312 // redeclaration, then pretend that we don't know about this 1313 // library built-in. 1314 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1315 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1316 << Old << Old->getType(); 1317 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1318 Old->setInvalidDecl(); 1319 return false; 1320 } 1321 1322 PrevDiag = diag::note_previous_builtin_declaration; 1323 } 1324 1325 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1326 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1327 return true; 1328} 1329 1330/// \brief Completes the merge of two function declarations that are 1331/// known to be compatible. 1332/// 1333/// This routine handles the merging of attributes and other 1334/// properties of function declarations form the old declaration to 1335/// the new declaration, once we know that New is in fact a 1336/// redeclaration of Old. 1337/// 1338/// \returns false 1339bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1340 // Merge the attributes 1341 MergeAttributes(New, Old, Context); 1342 1343 // Merge the storage class. 1344 if (Old->getStorageClass() != FunctionDecl::Extern && 1345 Old->getStorageClass() != FunctionDecl::None) 1346 New->setStorageClass(Old->getStorageClass()); 1347 1348 // Merge "pure" flag. 1349 if (Old->isPure()) 1350 New->setPure(); 1351 1352 // Merge the "deleted" flag. 1353 if (Old->isDeleted()) 1354 New->setDeleted(); 1355 1356 if (getLangOptions().CPlusPlus) 1357 return MergeCXXFunctionDecl(New, Old); 1358 1359 return false; 1360} 1361 1362/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1363/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1364/// situation, merging decls or emitting diagnostics as appropriate. 1365/// 1366/// Tentative definition rules (C99 6.9.2p2) are checked by 1367/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1368/// definitions here, since the initializer hasn't been attached. 1369/// 1370void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1371 // If the new decl is already invalid, don't do any other checking. 1372 if (New->isInvalidDecl()) 1373 return; 1374 1375 // Verify the old decl was also a variable. 1376 VarDecl *Old = 0; 1377 if (!Previous.isSingleResult() || 1378 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1379 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1380 << New->getDeclName(); 1381 Diag(Previous.getRepresentativeDecl()->getLocation(), 1382 diag::note_previous_definition); 1383 return New->setInvalidDecl(); 1384 } 1385 1386 MergeAttributes(New, Old, Context); 1387 1388 // Merge the types 1389 QualType MergedT; 1390 if (getLangOptions().CPlusPlus) { 1391 if (Context.hasSameType(New->getType(), Old->getType())) 1392 MergedT = New->getType(); 1393 // C++ [basic.link]p10: 1394 // [...] the types specified by all declarations referring to a given 1395 // object or function shall be identical, except that declarations for an 1396 // array object can specify array types that differ by the presence or 1397 // absence of a major array bound (8.3.4). 1398 else if (Old->getType()->isIncompleteArrayType() && 1399 New->getType()->isArrayType()) { 1400 CanQual<ArrayType> OldArray 1401 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1402 CanQual<ArrayType> NewArray 1403 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1404 if (OldArray->getElementType() == NewArray->getElementType()) 1405 MergedT = New->getType(); 1406 } else if (Old->getType()->isArrayType() && 1407 New->getType()->isIncompleteArrayType()) { 1408 CanQual<ArrayType> OldArray 1409 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1410 CanQual<ArrayType> NewArray 1411 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1412 if (OldArray->getElementType() == NewArray->getElementType()) 1413 MergedT = Old->getType(); 1414 } else if (New->getType()->isObjCObjectPointerType() 1415 && Old->getType()->isObjCObjectPointerType()) { 1416 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1417 } 1418 } else { 1419 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1420 } 1421 if (MergedT.isNull()) { 1422 Diag(New->getLocation(), diag::err_redefinition_different_type) 1423 << New->getDeclName(); 1424 Diag(Old->getLocation(), diag::note_previous_definition); 1425 return New->setInvalidDecl(); 1426 } 1427 New->setType(MergedT); 1428 1429 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1430 if (New->getStorageClass() == VarDecl::Static && 1431 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1432 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1433 Diag(Old->getLocation(), diag::note_previous_definition); 1434 return New->setInvalidDecl(); 1435 } 1436 // C99 6.2.2p4: 1437 // For an identifier declared with the storage-class specifier 1438 // extern in a scope in which a prior declaration of that 1439 // identifier is visible,23) if the prior declaration specifies 1440 // internal or external linkage, the linkage of the identifier at 1441 // the later declaration is the same as the linkage specified at 1442 // the prior declaration. If no prior declaration is visible, or 1443 // if the prior declaration specifies no linkage, then the 1444 // identifier has external linkage. 1445 if (New->hasExternalStorage() && Old->hasLinkage()) 1446 /* Okay */; 1447 else if (New->getStorageClass() != VarDecl::Static && 1448 Old->getStorageClass() == VarDecl::Static) { 1449 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1450 Diag(Old->getLocation(), diag::note_previous_definition); 1451 return New->setInvalidDecl(); 1452 } 1453 1454 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1455 1456 // FIXME: The test for external storage here seems wrong? We still 1457 // need to check for mismatches. 1458 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1459 // Don't complain about out-of-line definitions of static members. 1460 !(Old->getLexicalDeclContext()->isRecord() && 1461 !New->getLexicalDeclContext()->isRecord())) { 1462 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1463 Diag(Old->getLocation(), diag::note_previous_definition); 1464 return New->setInvalidDecl(); 1465 } 1466 1467 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1468 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1469 Diag(Old->getLocation(), diag::note_previous_definition); 1470 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1471 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1472 Diag(Old->getLocation(), diag::note_previous_definition); 1473 } 1474 1475 // C++ doesn't have tentative definitions, so go right ahead and check here. 1476 const VarDecl *Def; 1477 if (getLangOptions().CPlusPlus && 1478 New->isThisDeclarationADefinition() == VarDecl::Definition && 1479 (Def = Old->getDefinition())) { 1480 Diag(New->getLocation(), diag::err_redefinition) 1481 << New->getDeclName(); 1482 Diag(Def->getLocation(), diag::note_previous_definition); 1483 New->setInvalidDecl(); 1484 return; 1485 } 1486 // c99 6.2.2 P4. 1487 // For an identifier declared with the storage-class specifier extern in a 1488 // scope in which a prior declaration of that identifier is visible, if 1489 // the prior declaration specifies internal or external linkage, the linkage 1490 // of the identifier at the later declaration is the same as the linkage 1491 // specified at the prior declaration. 1492 // FIXME. revisit this code. 1493 if (New->hasExternalStorage() && 1494 Old->getLinkage() == InternalLinkage && 1495 New->getDeclContext() == Old->getDeclContext()) 1496 New->setStorageClass(Old->getStorageClass()); 1497 1498 // Keep a chain of previous declarations. 1499 New->setPreviousDeclaration(Old); 1500 1501 // Inherit access appropriately. 1502 New->setAccess(Old->getAccess()); 1503} 1504 1505/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1506/// no declarator (e.g. "struct foo;") is parsed. 1507Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1508 DeclSpec &DS) { 1509 // FIXME: Error on auto/register at file scope 1510 // FIXME: Error on inline/virtual/explicit 1511 // FIXME: Warn on useless __thread 1512 // FIXME: Warn on useless const/volatile 1513 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1514 // FIXME: Warn on useless attributes 1515 Decl *TagD = 0; 1516 TagDecl *Tag = 0; 1517 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1518 DS.getTypeSpecType() == DeclSpec::TST_struct || 1519 DS.getTypeSpecType() == DeclSpec::TST_union || 1520 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1521 TagD = static_cast<Decl *>(DS.getTypeRep()); 1522 1523 if (!TagD) // We probably had an error 1524 return DeclPtrTy(); 1525 1526 // Note that the above type specs guarantee that the 1527 // type rep is a Decl, whereas in many of the others 1528 // it's a Type. 1529 Tag = dyn_cast<TagDecl>(TagD); 1530 } 1531 1532 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1533 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1534 // or incomplete types shall not be restrict-qualified." 1535 if (TypeQuals & DeclSpec::TQ_restrict) 1536 Diag(DS.getRestrictSpecLoc(), 1537 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1538 << DS.getSourceRange(); 1539 } 1540 1541 if (DS.isFriendSpecified()) { 1542 // If we're dealing with a class template decl, assume that the 1543 // template routines are handling it. 1544 if (TagD && isa<ClassTemplateDecl>(TagD)) 1545 return DeclPtrTy(); 1546 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1547 } 1548 1549 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1550 // If there are attributes in the DeclSpec, apply them to the record. 1551 if (const AttributeList *AL = DS.getAttributes()) 1552 ProcessDeclAttributeList(S, Record, AL); 1553 1554 if (!Record->getDeclName() && Record->isDefinition() && 1555 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1556 if (getLangOptions().CPlusPlus || 1557 Record->getDeclContext()->isRecord()) 1558 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1559 1560 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1561 << DS.getSourceRange(); 1562 } 1563 1564 // Microsoft allows unnamed struct/union fields. Don't complain 1565 // about them. 1566 // FIXME: Should we support Microsoft's extensions in this area? 1567 if (Record->getDeclName() && getLangOptions().Microsoft) 1568 return DeclPtrTy::make(Tag); 1569 } 1570 1571 if (getLangOptions().CPlusPlus && 1572 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1573 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1574 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1575 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1576 Diag(Enum->getLocation(), diag::ext_no_declarators) 1577 << DS.getSourceRange(); 1578 1579 if (!DS.isMissingDeclaratorOk() && 1580 DS.getTypeSpecType() != DeclSpec::TST_error) { 1581 // Warn about typedefs of enums without names, since this is an 1582 // extension in both Microsoft and GNU. 1583 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1584 Tag && isa<EnumDecl>(Tag)) { 1585 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1586 << DS.getSourceRange(); 1587 return DeclPtrTy::make(Tag); 1588 } 1589 1590 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1591 << DS.getSourceRange(); 1592 } 1593 1594 return DeclPtrTy::make(TagD); 1595} 1596 1597/// We are trying to inject an anonymous member into the given scope; 1598/// check if there's an existing declaration that can't be overloaded. 1599/// 1600/// \return true if this is a forbidden redeclaration 1601static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1602 Scope *S, 1603 DeclContext *Owner, 1604 DeclarationName Name, 1605 SourceLocation NameLoc, 1606 unsigned diagnostic) { 1607 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1608 Sema::ForRedeclaration); 1609 if (!SemaRef.LookupName(R, S)) return false; 1610 1611 if (R.getAsSingle<TagDecl>()) 1612 return false; 1613 1614 // Pick a representative declaration. 1615 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1616 if (PrevDecl && Owner->isRecord()) { 1617 RecordDecl *Record = cast<RecordDecl>(Owner); 1618 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1619 return false; 1620 } 1621 1622 SemaRef.Diag(NameLoc, diagnostic) << Name; 1623 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1624 1625 return true; 1626} 1627 1628/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1629/// anonymous struct or union AnonRecord into the owning context Owner 1630/// and scope S. This routine will be invoked just after we realize 1631/// that an unnamed union or struct is actually an anonymous union or 1632/// struct, e.g., 1633/// 1634/// @code 1635/// union { 1636/// int i; 1637/// float f; 1638/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1639/// // f into the surrounding scope.x 1640/// @endcode 1641/// 1642/// This routine is recursive, injecting the names of nested anonymous 1643/// structs/unions into the owning context and scope as well. 1644static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1645 DeclContext *Owner, 1646 RecordDecl *AnonRecord, 1647 AccessSpecifier AS) { 1648 unsigned diagKind 1649 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1650 : diag::err_anonymous_struct_member_redecl; 1651 1652 bool Invalid = false; 1653 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1654 FEnd = AnonRecord->field_end(); 1655 F != FEnd; ++F) { 1656 if ((*F)->getDeclName()) { 1657 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1658 (*F)->getLocation(), diagKind)) { 1659 // C++ [class.union]p2: 1660 // The names of the members of an anonymous union shall be 1661 // distinct from the names of any other entity in the 1662 // scope in which the anonymous union is declared. 1663 Invalid = true; 1664 } else { 1665 // C++ [class.union]p2: 1666 // For the purpose of name lookup, after the anonymous union 1667 // definition, the members of the anonymous union are 1668 // considered to have been defined in the scope in which the 1669 // anonymous union is declared. 1670 Owner->makeDeclVisibleInContext(*F); 1671 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1672 SemaRef.IdResolver.AddDecl(*F); 1673 1674 // That includes picking up the appropriate access specifier. 1675 if (AS != AS_none) (*F)->setAccess(AS); 1676 } 1677 } else if (const RecordType *InnerRecordType 1678 = (*F)->getType()->getAs<RecordType>()) { 1679 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1680 if (InnerRecord->isAnonymousStructOrUnion()) 1681 Invalid = Invalid || 1682 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1683 InnerRecord, AS); 1684 } 1685 } 1686 1687 return Invalid; 1688} 1689 1690/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1691/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1692/// illegal input values are mapped to VarDecl::None. 1693static VarDecl::StorageClass 1694StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1695 switch (StorageClassSpec) { 1696 case DeclSpec::SCS_unspecified: return VarDecl::None; 1697 case DeclSpec::SCS_extern: return VarDecl::Extern; 1698 case DeclSpec::SCS_static: return VarDecl::Static; 1699 case DeclSpec::SCS_auto: return VarDecl::Auto; 1700 case DeclSpec::SCS_register: return VarDecl::Register; 1701 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1702 // Illegal SCSs map to None: error reporting is up to the caller. 1703 case DeclSpec::SCS_mutable: // Fall through. 1704 case DeclSpec::SCS_typedef: return VarDecl::None; 1705 } 1706 llvm_unreachable("unknown storage class specifier"); 1707} 1708 1709/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1710/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1711/// illegal input values are mapped to FunctionDecl::None. 1712static FunctionDecl::StorageClass 1713StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 1714 switch (StorageClassSpec) { 1715 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1716 case DeclSpec::SCS_extern: return FunctionDecl::Extern; 1717 case DeclSpec::SCS_static: return FunctionDecl::Static; 1718 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1719 // Illegal SCSs map to None: error reporting is up to the caller. 1720 case DeclSpec::SCS_auto: // Fall through. 1721 case DeclSpec::SCS_mutable: // Fall through. 1722 case DeclSpec::SCS_register: // Fall through. 1723 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1724 } 1725 llvm_unreachable("unknown storage class specifier"); 1726} 1727 1728/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1729/// anonymous structure or union. Anonymous unions are a C++ feature 1730/// (C++ [class.union]) and a GNU C extension; anonymous structures 1731/// are a GNU C and GNU C++ extension. 1732Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1733 AccessSpecifier AS, 1734 RecordDecl *Record) { 1735 DeclContext *Owner = Record->getDeclContext(); 1736 1737 // Diagnose whether this anonymous struct/union is an extension. 1738 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1739 Diag(Record->getLocation(), diag::ext_anonymous_union); 1740 else if (!Record->isUnion()) 1741 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1742 1743 // C and C++ require different kinds of checks for anonymous 1744 // structs/unions. 1745 bool Invalid = false; 1746 if (getLangOptions().CPlusPlus) { 1747 const char* PrevSpec = 0; 1748 unsigned DiagID; 1749 // C++ [class.union]p3: 1750 // Anonymous unions declared in a named namespace or in the 1751 // global namespace shall be declared static. 1752 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1753 (isa<TranslationUnitDecl>(Owner) || 1754 (isa<NamespaceDecl>(Owner) && 1755 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1756 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1757 Invalid = true; 1758 1759 // Recover by adding 'static'. 1760 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1761 PrevSpec, DiagID); 1762 } 1763 // C++ [class.union]p3: 1764 // A storage class is not allowed in a declaration of an 1765 // anonymous union in a class scope. 1766 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1767 isa<RecordDecl>(Owner)) { 1768 Diag(DS.getStorageClassSpecLoc(), 1769 diag::err_anonymous_union_with_storage_spec); 1770 Invalid = true; 1771 1772 // Recover by removing the storage specifier. 1773 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1774 PrevSpec, DiagID); 1775 } 1776 1777 // C++ [class.union]p2: 1778 // The member-specification of an anonymous union shall only 1779 // define non-static data members. [Note: nested types and 1780 // functions cannot be declared within an anonymous union. ] 1781 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1782 MemEnd = Record->decls_end(); 1783 Mem != MemEnd; ++Mem) { 1784 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1785 // C++ [class.union]p3: 1786 // An anonymous union shall not have private or protected 1787 // members (clause 11). 1788 assert(FD->getAccess() != AS_none); 1789 if (FD->getAccess() != AS_public) { 1790 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1791 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1792 Invalid = true; 1793 } 1794 } else if ((*Mem)->isImplicit()) { 1795 // Any implicit members are fine. 1796 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1797 // This is a type that showed up in an 1798 // elaborated-type-specifier inside the anonymous struct or 1799 // union, but which actually declares a type outside of the 1800 // anonymous struct or union. It's okay. 1801 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1802 if (!MemRecord->isAnonymousStructOrUnion() && 1803 MemRecord->getDeclName()) { 1804 // This is a nested type declaration. 1805 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1806 << (int)Record->isUnion(); 1807 Invalid = true; 1808 } 1809 } else if (isa<AccessSpecDecl>(*Mem)) { 1810 // Any access specifier is fine. 1811 } else { 1812 // We have something that isn't a non-static data 1813 // member. Complain about it. 1814 unsigned DK = diag::err_anonymous_record_bad_member; 1815 if (isa<TypeDecl>(*Mem)) 1816 DK = diag::err_anonymous_record_with_type; 1817 else if (isa<FunctionDecl>(*Mem)) 1818 DK = diag::err_anonymous_record_with_function; 1819 else if (isa<VarDecl>(*Mem)) 1820 DK = diag::err_anonymous_record_with_static; 1821 Diag((*Mem)->getLocation(), DK) 1822 << (int)Record->isUnion(); 1823 Invalid = true; 1824 } 1825 } 1826 } 1827 1828 if (!Record->isUnion() && !Owner->isRecord()) { 1829 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1830 << (int)getLangOptions().CPlusPlus; 1831 Invalid = true; 1832 } 1833 1834 // Mock up a declarator. 1835 Declarator Dc(DS, Declarator::TypeNameContext); 1836 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1837 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1838 1839 // Create a declaration for this anonymous struct/union. 1840 NamedDecl *Anon = 0; 1841 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1842 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1843 /*IdentifierInfo=*/0, 1844 Context.getTypeDeclType(Record), 1845 TInfo, 1846 /*BitWidth=*/0, /*Mutable=*/false); 1847 Anon->setAccess(AS); 1848 if (getLangOptions().CPlusPlus) { 1849 FieldCollector->Add(cast<FieldDecl>(Anon)); 1850 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1851 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1852 } 1853 } else { 1854 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1855 assert(SCSpec != DeclSpec::SCS_typedef && 1856 "Parser allowed 'typedef' as storage class VarDecl."); 1857 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 1858 if (SCSpec == DeclSpec::SCS_mutable) { 1859 // mutable can only appear on non-static class members, so it's always 1860 // an error here 1861 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1862 Invalid = true; 1863 SC = VarDecl::None; 1864 } 1865 SCSpec = DS.getStorageClassSpecAsWritten(); 1866 VarDecl::StorageClass SCAsWritten 1867 = StorageClassSpecToVarDeclStorageClass(SCSpec); 1868 1869 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1870 /*IdentifierInfo=*/0, 1871 Context.getTypeDeclType(Record), 1872 TInfo, SC, SCAsWritten); 1873 } 1874 Anon->setImplicit(); 1875 1876 // Add the anonymous struct/union object to the current 1877 // context. We'll be referencing this object when we refer to one of 1878 // its members. 1879 Owner->addDecl(Anon); 1880 1881 // Inject the members of the anonymous struct/union into the owning 1882 // context and into the identifier resolver chain for name lookup 1883 // purposes. 1884 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1885 Invalid = true; 1886 1887 // Mark this as an anonymous struct/union type. Note that we do not 1888 // do this until after we have already checked and injected the 1889 // members of this anonymous struct/union type, because otherwise 1890 // the members could be injected twice: once by DeclContext when it 1891 // builds its lookup table, and once by 1892 // InjectAnonymousStructOrUnionMembers. 1893 Record->setAnonymousStructOrUnion(true); 1894 1895 if (Invalid) 1896 Anon->setInvalidDecl(); 1897 1898 return DeclPtrTy::make(Anon); 1899} 1900 1901 1902/// GetNameForDeclarator - Determine the full declaration name for the 1903/// given Declarator. 1904DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 1905 return GetNameFromUnqualifiedId(D.getName()); 1906} 1907 1908/// \brief Retrieves the declaration name from a parsed unqualified-id. 1909DeclarationNameInfo 1910Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1911 DeclarationNameInfo NameInfo; 1912 NameInfo.setLoc(Name.StartLocation); 1913 1914 switch (Name.getKind()) { 1915 1916 case UnqualifiedId::IK_Identifier: 1917 NameInfo.setName(Name.Identifier); 1918 NameInfo.setLoc(Name.StartLocation); 1919 return NameInfo; 1920 1921 case UnqualifiedId::IK_OperatorFunctionId: 1922 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 1923 Name.OperatorFunctionId.Operator)); 1924 NameInfo.setLoc(Name.StartLocation); 1925 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 1926 = Name.OperatorFunctionId.SymbolLocations[0]; 1927 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 1928 = Name.EndLocation.getRawEncoding(); 1929 return NameInfo; 1930 1931 case UnqualifiedId::IK_LiteralOperatorId: 1932 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 1933 Name.Identifier)); 1934 NameInfo.setLoc(Name.StartLocation); 1935 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 1936 return NameInfo; 1937 1938 case UnqualifiedId::IK_ConversionFunctionId: { 1939 TypeSourceInfo *TInfo; 1940 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 1941 if (Ty.isNull()) 1942 return DeclarationNameInfo(); 1943 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 1944 Context.getCanonicalType(Ty))); 1945 NameInfo.setLoc(Name.StartLocation); 1946 NameInfo.setNamedTypeInfo(TInfo); 1947 return NameInfo; 1948 } 1949 1950 case UnqualifiedId::IK_ConstructorName: { 1951 TypeSourceInfo *TInfo; 1952 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 1953 if (Ty.isNull()) 1954 return DeclarationNameInfo(); 1955 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 1956 Context.getCanonicalType(Ty))); 1957 NameInfo.setLoc(Name.StartLocation); 1958 NameInfo.setNamedTypeInfo(TInfo); 1959 return NameInfo; 1960 } 1961 1962 case UnqualifiedId::IK_ConstructorTemplateId: { 1963 // In well-formed code, we can only have a constructor 1964 // template-id that refers to the current context, so go there 1965 // to find the actual type being constructed. 1966 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1967 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1968 return DeclarationNameInfo(); 1969 1970 // Determine the type of the class being constructed. 1971 QualType CurClassType = Context.getTypeDeclType(CurClass); 1972 1973 // FIXME: Check two things: that the template-id names the same type as 1974 // CurClassType, and that the template-id does not occur when the name 1975 // was qualified. 1976 1977 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 1978 Context.getCanonicalType(CurClassType))); 1979 NameInfo.setLoc(Name.StartLocation); 1980 // FIXME: should we retrieve TypeSourceInfo? 1981 NameInfo.setNamedTypeInfo(0); 1982 return NameInfo; 1983 } 1984 1985 case UnqualifiedId::IK_DestructorName: { 1986 TypeSourceInfo *TInfo; 1987 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 1988 if (Ty.isNull()) 1989 return DeclarationNameInfo(); 1990 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 1991 Context.getCanonicalType(Ty))); 1992 NameInfo.setLoc(Name.StartLocation); 1993 NameInfo.setNamedTypeInfo(TInfo); 1994 return NameInfo; 1995 } 1996 1997 case UnqualifiedId::IK_TemplateId: { 1998 TemplateName TName 1999 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 2000 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2001 return Context.getNameForTemplate(TName, TNameLoc); 2002 } 2003 2004 } // switch (Name.getKind()) 2005 2006 assert(false && "Unknown name kind"); 2007 return DeclarationNameInfo(); 2008} 2009 2010/// isNearlyMatchingFunction - Determine whether the C++ functions 2011/// Declaration and Definition are "nearly" matching. This heuristic 2012/// is used to improve diagnostics in the case where an out-of-line 2013/// function definition doesn't match any declaration within 2014/// the class or namespace. 2015static bool isNearlyMatchingFunction(ASTContext &Context, 2016 FunctionDecl *Declaration, 2017 FunctionDecl *Definition) { 2018 if (Declaration->param_size() != Definition->param_size()) 2019 return false; 2020 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2021 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2022 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2023 2024 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2025 DefParamTy.getNonReferenceType())) 2026 return false; 2027 } 2028 2029 return true; 2030} 2031 2032/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2033/// declarator needs to be rebuilt in the current instantiation. 2034/// Any bits of declarator which appear before the name are valid for 2035/// consideration here. That's specifically the type in the decl spec 2036/// and the base type in any member-pointer chunks. 2037static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2038 DeclarationName Name) { 2039 // The types we specifically need to rebuild are: 2040 // - typenames, typeofs, and decltypes 2041 // - types which will become injected class names 2042 // Of course, we also need to rebuild any type referencing such a 2043 // type. It's safest to just say "dependent", but we call out a 2044 // few cases here. 2045 2046 DeclSpec &DS = D.getMutableDeclSpec(); 2047 switch (DS.getTypeSpecType()) { 2048 case DeclSpec::TST_typename: 2049 case DeclSpec::TST_typeofType: 2050 case DeclSpec::TST_typeofExpr: 2051 case DeclSpec::TST_decltype: { 2052 // Grab the type from the parser. 2053 TypeSourceInfo *TSI = 0; 2054 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2055 if (T.isNull() || !T->isDependentType()) break; 2056 2057 // Make sure there's a type source info. This isn't really much 2058 // of a waste; most dependent types should have type source info 2059 // attached already. 2060 if (!TSI) 2061 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2062 2063 // Rebuild the type in the current instantiation. 2064 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2065 if (!TSI) return true; 2066 2067 // Store the new type back in the decl spec. 2068 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2069 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2070 break; 2071 } 2072 2073 default: 2074 // Nothing to do for these decl specs. 2075 break; 2076 } 2077 2078 // It doesn't matter what order we do this in. 2079 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2080 DeclaratorChunk &Chunk = D.getTypeObject(I); 2081 2082 // The only type information in the declarator which can come 2083 // before the declaration name is the base type of a member 2084 // pointer. 2085 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2086 continue; 2087 2088 // Rebuild the scope specifier in-place. 2089 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2090 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2091 return true; 2092 } 2093 2094 return false; 2095} 2096 2097Sema::DeclPtrTy 2098Sema::HandleDeclarator(Scope *S, Declarator &D, 2099 MultiTemplateParamsArg TemplateParamLists, 2100 bool IsFunctionDefinition) { 2101 // TODO: consider using NameInfo for diagnostic. 2102 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2103 DeclarationName Name = NameInfo.getName(); 2104 2105 // All of these full declarators require an identifier. If it doesn't have 2106 // one, the ParsedFreeStandingDeclSpec action should be used. 2107 if (!Name) { 2108 if (!D.isInvalidType()) // Reject this if we think it is valid. 2109 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2110 diag::err_declarator_need_ident) 2111 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2112 return DeclPtrTy(); 2113 } 2114 2115 // The scope passed in may not be a decl scope. Zip up the scope tree until 2116 // we find one that is. 2117 while ((S->getFlags() & Scope::DeclScope) == 0 || 2118 (S->getFlags() & Scope::TemplateParamScope) != 0) 2119 S = S->getParent(); 2120 2121 DeclContext *DC = CurContext; 2122 if (D.getCXXScopeSpec().isInvalid()) 2123 D.setInvalidType(); 2124 else if (D.getCXXScopeSpec().isSet()) { 2125 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2126 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2127 if (!DC) { 2128 // If we could not compute the declaration context, it's because the 2129 // declaration context is dependent but does not refer to a class, 2130 // class template, or class template partial specialization. Complain 2131 // and return early, to avoid the coming semantic disaster. 2132 Diag(D.getIdentifierLoc(), 2133 diag::err_template_qualified_declarator_no_match) 2134 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2135 << D.getCXXScopeSpec().getRange(); 2136 return DeclPtrTy(); 2137 } 2138 2139 bool IsDependentContext = DC->isDependentContext(); 2140 2141 if (!IsDependentContext && 2142 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2143 return DeclPtrTy(); 2144 2145 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2146 Diag(D.getIdentifierLoc(), 2147 diag::err_member_def_undefined_record) 2148 << Name << DC << D.getCXXScopeSpec().getRange(); 2149 D.setInvalidType(); 2150 } 2151 2152 // Check whether we need to rebuild the type of the given 2153 // declaration in the current instantiation. 2154 if (EnteringContext && IsDependentContext && 2155 TemplateParamLists.size() != 0) { 2156 ContextRAII SavedContext(*this, DC); 2157 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2158 D.setInvalidType(); 2159 } 2160 } 2161 2162 NamedDecl *New; 2163 2164 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2165 QualType R = TInfo->getType(); 2166 2167 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2168 ForRedeclaration); 2169 2170 // See if this is a redefinition of a variable in the same scope. 2171 if (!D.getCXXScopeSpec().isSet()) { 2172 bool IsLinkageLookup = false; 2173 2174 // If the declaration we're planning to build will be a function 2175 // or object with linkage, then look for another declaration with 2176 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2177 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2178 /* Do nothing*/; 2179 else if (R->isFunctionType()) { 2180 if (CurContext->isFunctionOrMethod() || 2181 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2182 IsLinkageLookup = true; 2183 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2184 IsLinkageLookup = true; 2185 else if (CurContext->getLookupContext()->isTranslationUnit() && 2186 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2187 IsLinkageLookup = true; 2188 2189 if (IsLinkageLookup) 2190 Previous.clear(LookupRedeclarationWithLinkage); 2191 2192 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2193 } else { // Something like "int foo::x;" 2194 LookupQualifiedName(Previous, DC); 2195 2196 // Don't consider using declarations as previous declarations for 2197 // out-of-line members. 2198 RemoveUsingDecls(Previous); 2199 2200 // C++ 7.3.1.2p2: 2201 // Members (including explicit specializations of templates) of a named 2202 // namespace can also be defined outside that namespace by explicit 2203 // qualification of the name being defined, provided that the entity being 2204 // defined was already declared in the namespace and the definition appears 2205 // after the point of declaration in a namespace that encloses the 2206 // declarations namespace. 2207 // 2208 // Note that we only check the context at this point. We don't yet 2209 // have enough information to make sure that PrevDecl is actually 2210 // the declaration we want to match. For example, given: 2211 // 2212 // class X { 2213 // void f(); 2214 // void f(float); 2215 // }; 2216 // 2217 // void X::f(int) { } // ill-formed 2218 // 2219 // In this case, PrevDecl will point to the overload set 2220 // containing the two f's declared in X, but neither of them 2221 // matches. 2222 2223 // First check whether we named the global scope. 2224 if (isa<TranslationUnitDecl>(DC)) { 2225 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2226 << Name << D.getCXXScopeSpec().getRange(); 2227 } else { 2228 DeclContext *Cur = CurContext; 2229 while (isa<LinkageSpecDecl>(Cur)) 2230 Cur = Cur->getParent(); 2231 if (!Cur->Encloses(DC)) { 2232 // The qualifying scope doesn't enclose the original declaration. 2233 // Emit diagnostic based on current scope. 2234 SourceLocation L = D.getIdentifierLoc(); 2235 SourceRange R = D.getCXXScopeSpec().getRange(); 2236 if (isa<FunctionDecl>(Cur)) 2237 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2238 else 2239 Diag(L, diag::err_invalid_declarator_scope) 2240 << Name << cast<NamedDecl>(DC) << R; 2241 D.setInvalidType(); 2242 } 2243 } 2244 } 2245 2246 if (Previous.isSingleResult() && 2247 Previous.getFoundDecl()->isTemplateParameter()) { 2248 // Maybe we will complain about the shadowed template parameter. 2249 if (!D.isInvalidType()) 2250 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2251 Previous.getFoundDecl())) 2252 D.setInvalidType(); 2253 2254 // Just pretend that we didn't see the previous declaration. 2255 Previous.clear(); 2256 } 2257 2258 // In C++, the previous declaration we find might be a tag type 2259 // (class or enum). In this case, the new declaration will hide the 2260 // tag type. Note that this does does not apply if we're declaring a 2261 // typedef (C++ [dcl.typedef]p4). 2262 if (Previous.isSingleTagDecl() && 2263 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2264 Previous.clear(); 2265 2266 bool Redeclaration = false; 2267 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2268 if (TemplateParamLists.size()) { 2269 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2270 return DeclPtrTy(); 2271 } 2272 2273 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2274 } else if (R->isFunctionType()) { 2275 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2276 move(TemplateParamLists), 2277 IsFunctionDefinition, Redeclaration); 2278 } else { 2279 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2280 move(TemplateParamLists), 2281 Redeclaration); 2282 } 2283 2284 if (New == 0) 2285 return DeclPtrTy(); 2286 2287 // If this has an identifier and is not an invalid redeclaration or 2288 // function template specialization, add it to the scope stack. 2289 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2290 PushOnScopeChains(New, S); 2291 2292 return DeclPtrTy::make(New); 2293} 2294 2295/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2296/// types into constant array types in certain situations which would otherwise 2297/// be errors (for GCC compatibility). 2298static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2299 ASTContext &Context, 2300 bool &SizeIsNegative) { 2301 // This method tries to turn a variable array into a constant 2302 // array even when the size isn't an ICE. This is necessary 2303 // for compatibility with code that depends on gcc's buggy 2304 // constant expression folding, like struct {char x[(int)(char*)2];} 2305 SizeIsNegative = false; 2306 2307 QualifierCollector Qs; 2308 const Type *Ty = Qs.strip(T); 2309 2310 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2311 QualType Pointee = PTy->getPointeeType(); 2312 QualType FixedType = 2313 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2314 if (FixedType.isNull()) return FixedType; 2315 FixedType = Context.getPointerType(FixedType); 2316 return Qs.apply(FixedType); 2317 } 2318 2319 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2320 if (!VLATy) 2321 return QualType(); 2322 // FIXME: We should probably handle this case 2323 if (VLATy->getElementType()->isVariablyModifiedType()) 2324 return QualType(); 2325 2326 Expr::EvalResult EvalResult; 2327 if (!VLATy->getSizeExpr() || 2328 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2329 !EvalResult.Val.isInt()) 2330 return QualType(); 2331 2332 llvm::APSInt &Res = EvalResult.Val.getInt(); 2333 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2334 // TODO: preserve the size expression in declarator info 2335 return Context.getConstantArrayType(VLATy->getElementType(), 2336 Res, ArrayType::Normal, 0); 2337 } 2338 2339 SizeIsNegative = true; 2340 return QualType(); 2341} 2342 2343/// \brief Register the given locally-scoped external C declaration so 2344/// that it can be found later for redeclarations 2345void 2346Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2347 const LookupResult &Previous, 2348 Scope *S) { 2349 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2350 "Decl is not a locally-scoped decl!"); 2351 // Note that we have a locally-scoped external with this name. 2352 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2353 2354 if (!Previous.isSingleResult()) 2355 return; 2356 2357 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2358 2359 // If there was a previous declaration of this variable, it may be 2360 // in our identifier chain. Update the identifier chain with the new 2361 // declaration. 2362 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2363 // The previous declaration was found on the identifer resolver 2364 // chain, so remove it from its scope. 2365 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2366 S = S->getParent(); 2367 2368 if (S) 2369 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2370 } 2371} 2372 2373/// \brief Diagnose function specifiers on a declaration of an identifier that 2374/// does not identify a function. 2375void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2376 // FIXME: We should probably indicate the identifier in question to avoid 2377 // confusion for constructs like "inline int a(), b;" 2378 if (D.getDeclSpec().isInlineSpecified()) 2379 Diag(D.getDeclSpec().getInlineSpecLoc(), 2380 diag::err_inline_non_function); 2381 2382 if (D.getDeclSpec().isVirtualSpecified()) 2383 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2384 diag::err_virtual_non_function); 2385 2386 if (D.getDeclSpec().isExplicitSpecified()) 2387 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2388 diag::err_explicit_non_function); 2389} 2390 2391NamedDecl* 2392Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2393 QualType R, TypeSourceInfo *TInfo, 2394 LookupResult &Previous, bool &Redeclaration) { 2395 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2396 if (D.getCXXScopeSpec().isSet()) { 2397 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2398 << D.getCXXScopeSpec().getRange(); 2399 D.setInvalidType(); 2400 // Pretend we didn't see the scope specifier. 2401 DC = CurContext; 2402 Previous.clear(); 2403 } 2404 2405 if (getLangOptions().CPlusPlus) { 2406 // Check that there are no default arguments (C++ only). 2407 CheckExtraCXXDefaultArguments(D); 2408 } 2409 2410 DiagnoseFunctionSpecifiers(D); 2411 2412 if (D.getDeclSpec().isThreadSpecified()) 2413 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2414 2415 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2416 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2417 << D.getName().getSourceRange(); 2418 return 0; 2419 } 2420 2421 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2422 if (!NewTD) return 0; 2423 2424 // Handle attributes prior to checking for duplicates in MergeVarDecl 2425 ProcessDeclAttributes(S, NewTD, D); 2426 2427 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2428 // then it shall have block scope. 2429 // Note that variably modified types must be fixed before merging the decl so 2430 // that redeclarations will match. 2431 QualType T = NewTD->getUnderlyingType(); 2432 if (T->isVariablyModifiedType()) { 2433 setFunctionHasBranchProtectedScope(); 2434 2435 if (S->getFnParent() == 0) { 2436 bool SizeIsNegative; 2437 QualType FixedTy = 2438 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2439 if (!FixedTy.isNull()) { 2440 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2441 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2442 } else { 2443 if (SizeIsNegative) 2444 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2445 else if (T->isVariableArrayType()) 2446 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2447 else 2448 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2449 NewTD->setInvalidDecl(); 2450 } 2451 } 2452 } 2453 2454 // Merge the decl with the existing one if appropriate. If the decl is 2455 // in an outer scope, it isn't the same thing. 2456 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2457 if (!Previous.empty()) { 2458 Redeclaration = true; 2459 MergeTypeDefDecl(NewTD, Previous); 2460 } 2461 2462 // If this is the C FILE type, notify the AST context. 2463 if (IdentifierInfo *II = NewTD->getIdentifier()) 2464 if (!NewTD->isInvalidDecl() && 2465 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2466 if (II->isStr("FILE")) 2467 Context.setFILEDecl(NewTD); 2468 else if (II->isStr("jmp_buf")) 2469 Context.setjmp_bufDecl(NewTD); 2470 else if (II->isStr("sigjmp_buf")) 2471 Context.setsigjmp_bufDecl(NewTD); 2472 } 2473 2474 return NewTD; 2475} 2476 2477/// \brief Determines whether the given declaration is an out-of-scope 2478/// previous declaration. 2479/// 2480/// This routine should be invoked when name lookup has found a 2481/// previous declaration (PrevDecl) that is not in the scope where a 2482/// new declaration by the same name is being introduced. If the new 2483/// declaration occurs in a local scope, previous declarations with 2484/// linkage may still be considered previous declarations (C99 2485/// 6.2.2p4-5, C++ [basic.link]p6). 2486/// 2487/// \param PrevDecl the previous declaration found by name 2488/// lookup 2489/// 2490/// \param DC the context in which the new declaration is being 2491/// declared. 2492/// 2493/// \returns true if PrevDecl is an out-of-scope previous declaration 2494/// for a new delcaration with the same name. 2495static bool 2496isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2497 ASTContext &Context) { 2498 if (!PrevDecl) 2499 return 0; 2500 2501 if (!PrevDecl->hasLinkage()) 2502 return false; 2503 2504 if (Context.getLangOptions().CPlusPlus) { 2505 // C++ [basic.link]p6: 2506 // If there is a visible declaration of an entity with linkage 2507 // having the same name and type, ignoring entities declared 2508 // outside the innermost enclosing namespace scope, the block 2509 // scope declaration declares that same entity and receives the 2510 // linkage of the previous declaration. 2511 DeclContext *OuterContext = DC->getLookupContext(); 2512 if (!OuterContext->isFunctionOrMethod()) 2513 // This rule only applies to block-scope declarations. 2514 return false; 2515 else { 2516 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2517 if (PrevOuterContext->isRecord()) 2518 // We found a member function: ignore it. 2519 return false; 2520 else { 2521 // Find the innermost enclosing namespace for the new and 2522 // previous declarations. 2523 while (!OuterContext->isFileContext()) 2524 OuterContext = OuterContext->getParent(); 2525 while (!PrevOuterContext->isFileContext()) 2526 PrevOuterContext = PrevOuterContext->getParent(); 2527 2528 // The previous declaration is in a different namespace, so it 2529 // isn't the same function. 2530 if (OuterContext->getPrimaryContext() != 2531 PrevOuterContext->getPrimaryContext()) 2532 return false; 2533 } 2534 } 2535 } 2536 2537 return true; 2538} 2539 2540static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2541 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2542 if (!SS.isSet()) return; 2543 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2544 SS.getRange()); 2545} 2546 2547NamedDecl* 2548Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2549 QualType R, TypeSourceInfo *TInfo, 2550 LookupResult &Previous, 2551 MultiTemplateParamsArg TemplateParamLists, 2552 bool &Redeclaration) { 2553 DeclarationName Name = GetNameForDeclarator(D).getName(); 2554 2555 // Check that there are no default arguments (C++ only). 2556 if (getLangOptions().CPlusPlus) 2557 CheckExtraCXXDefaultArguments(D); 2558 2559 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2560 assert(SCSpec != DeclSpec::SCS_typedef && 2561 "Parser allowed 'typedef' as storage class VarDecl."); 2562 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2563 if (SCSpec == DeclSpec::SCS_mutable) { 2564 // mutable can only appear on non-static class members, so it's always 2565 // an error here 2566 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2567 D.setInvalidType(); 2568 SC = VarDecl::None; 2569 } 2570 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2571 VarDecl::StorageClass SCAsWritten 2572 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2573 2574 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2575 if (!II) { 2576 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2577 << Name.getAsString(); 2578 return 0; 2579 } 2580 2581 DiagnoseFunctionSpecifiers(D); 2582 2583 if (!DC->isRecord() && S->getFnParent() == 0) { 2584 // C99 6.9p2: The storage-class specifiers auto and register shall not 2585 // appear in the declaration specifiers in an external declaration. 2586 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2587 2588 // If this is a register variable with an asm label specified, then this 2589 // is a GNU extension. 2590 if (SC == VarDecl::Register && D.getAsmLabel()) 2591 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2592 else 2593 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2594 D.setInvalidType(); 2595 } 2596 } 2597 if (DC->isRecord() && !CurContext->isRecord()) { 2598 // This is an out-of-line definition of a static data member. 2599 if (SC == VarDecl::Static) { 2600 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2601 diag::err_static_out_of_line) 2602 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2603 } else if (SC == VarDecl::None) 2604 SC = VarDecl::Static; 2605 } 2606 if (SC == VarDecl::Static) { 2607 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2608 if (RD->isLocalClass()) 2609 Diag(D.getIdentifierLoc(), 2610 diag::err_static_data_member_not_allowed_in_local_class) 2611 << Name << RD->getDeclName(); 2612 } 2613 } 2614 2615 // Match up the template parameter lists with the scope specifier, then 2616 // determine whether we have a template or a template specialization. 2617 bool isExplicitSpecialization = false; 2618 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2619 bool Invalid = false; 2620 if (TemplateParameterList *TemplateParams 2621 = MatchTemplateParametersToScopeSpecifier( 2622 D.getDeclSpec().getSourceRange().getBegin(), 2623 D.getCXXScopeSpec(), 2624 (TemplateParameterList**)TemplateParamLists.get(), 2625 TemplateParamLists.size(), 2626 /*never a friend*/ false, 2627 isExplicitSpecialization, 2628 Invalid)) { 2629 // All but one template parameter lists have been matching. 2630 --NumMatchedTemplateParamLists; 2631 2632 if (TemplateParams->size() > 0) { 2633 // There is no such thing as a variable template. 2634 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2635 << II 2636 << SourceRange(TemplateParams->getTemplateLoc(), 2637 TemplateParams->getRAngleLoc()); 2638 return 0; 2639 } else { 2640 // There is an extraneous 'template<>' for this variable. Complain 2641 // about it, but allow the declaration of the variable. 2642 Diag(TemplateParams->getTemplateLoc(), 2643 diag::err_template_variable_noparams) 2644 << II 2645 << SourceRange(TemplateParams->getTemplateLoc(), 2646 TemplateParams->getRAngleLoc()); 2647 2648 isExplicitSpecialization = true; 2649 } 2650 } 2651 2652 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2653 II, R, TInfo, SC, SCAsWritten); 2654 2655 if (D.isInvalidType() || Invalid) 2656 NewVD->setInvalidDecl(); 2657 2658 SetNestedNameSpecifier(NewVD, D); 2659 2660 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2661 NewVD->setTemplateParameterListsInfo(Context, 2662 NumMatchedTemplateParamLists, 2663 (TemplateParameterList**)TemplateParamLists.release()); 2664 } 2665 2666 if (D.getDeclSpec().isThreadSpecified()) { 2667 if (NewVD->hasLocalStorage()) 2668 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2669 else if (!Context.Target.isTLSSupported()) 2670 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2671 else 2672 NewVD->setThreadSpecified(true); 2673 } 2674 2675 // Set the lexical context. If the declarator has a C++ scope specifier, the 2676 // lexical context will be different from the semantic context. 2677 NewVD->setLexicalDeclContext(CurContext); 2678 2679 // Handle attributes prior to checking for duplicates in MergeVarDecl 2680 ProcessDeclAttributes(S, NewVD, D); 2681 2682 // Handle GNU asm-label extension (encoded as an attribute). 2683 if (Expr *E = (Expr*) D.getAsmLabel()) { 2684 // The parser guarantees this is a string. 2685 StringLiteral *SE = cast<StringLiteral>(E); 2686 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2687 } 2688 2689 // Diagnose shadowed variables before filtering for scope. 2690 if (!D.getCXXScopeSpec().isSet()) 2691 CheckShadow(S, NewVD, Previous); 2692 2693 // Don't consider existing declarations that are in a different 2694 // scope and are out-of-semantic-context declarations (if the new 2695 // declaration has linkage). 2696 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2697 2698 // Merge the decl with the existing one if appropriate. 2699 if (!Previous.empty()) { 2700 if (Previous.isSingleResult() && 2701 isa<FieldDecl>(Previous.getFoundDecl()) && 2702 D.getCXXScopeSpec().isSet()) { 2703 // The user tried to define a non-static data member 2704 // out-of-line (C++ [dcl.meaning]p1). 2705 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2706 << D.getCXXScopeSpec().getRange(); 2707 Previous.clear(); 2708 NewVD->setInvalidDecl(); 2709 } 2710 } else if (D.getCXXScopeSpec().isSet()) { 2711 // No previous declaration in the qualifying scope. 2712 Diag(D.getIdentifierLoc(), diag::err_no_member) 2713 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2714 << D.getCXXScopeSpec().getRange(); 2715 NewVD->setInvalidDecl(); 2716 } 2717 2718 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2719 2720 // This is an explicit specialization of a static data member. Check it. 2721 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2722 CheckMemberSpecialization(NewVD, Previous)) 2723 NewVD->setInvalidDecl(); 2724 2725 // attributes declared post-definition are currently ignored 2726 if (Previous.isSingleResult()) { 2727 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2728 if (Def && (Def = Def->getDefinition()) && 2729 Def != NewVD && D.hasAttributes()) { 2730 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2731 Diag(Def->getLocation(), diag::note_previous_definition); 2732 } 2733 } 2734 2735 // If this is a locally-scoped extern C variable, update the map of 2736 // such variables. 2737 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2738 !NewVD->isInvalidDecl()) 2739 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2740 2741 // If there's a #pragma GCC visibility in scope, and this isn't a class 2742 // member, set the visibility of this variable. 2743 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 2744 AddPushedVisibilityAttribute(NewVD); 2745 2746 return NewVD; 2747} 2748 2749/// \brief Diagnose variable or built-in function shadowing. Implements 2750/// -Wshadow. 2751/// 2752/// This method is called whenever a VarDecl is added to a "useful" 2753/// scope. 2754/// 2755/// \param S the scope in which the shadowing name is being declared 2756/// \param R the lookup of the name 2757/// 2758void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2759 // Return if warning is ignored. 2760 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2761 return; 2762 2763 // Don't diagnose declarations at file scope. The scope might not 2764 // have a DeclContext if (e.g.) we're parsing a function prototype. 2765 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2766 if (NewDC && NewDC->isFileContext()) 2767 return; 2768 2769 // Only diagnose if we're shadowing an unambiguous field or variable. 2770 if (R.getResultKind() != LookupResult::Found) 2771 return; 2772 2773 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2774 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2775 return; 2776 2777 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2778 2779 // Only warn about certain kinds of shadowing for class members. 2780 if (NewDC && NewDC->isRecord()) { 2781 // In particular, don't warn about shadowing non-class members. 2782 if (!OldDC->isRecord()) 2783 return; 2784 2785 // TODO: should we warn about static data members shadowing 2786 // static data members from base classes? 2787 2788 // TODO: don't diagnose for inaccessible shadowed members. 2789 // This is hard to do perfectly because we might friend the 2790 // shadowing context, but that's just a false negative. 2791 } 2792 2793 // Determine what kind of declaration we're shadowing. 2794 unsigned Kind; 2795 if (isa<RecordDecl>(OldDC)) { 2796 if (isa<FieldDecl>(ShadowedDecl)) 2797 Kind = 3; // field 2798 else 2799 Kind = 2; // static data member 2800 } else if (OldDC->isFileContext()) 2801 Kind = 1; // global 2802 else 2803 Kind = 0; // local 2804 2805 DeclarationName Name = R.getLookupName(); 2806 2807 // Emit warning and note. 2808 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2809 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2810} 2811 2812/// \brief Check -Wshadow without the advantage of a previous lookup. 2813void Sema::CheckShadow(Scope *S, VarDecl *D) { 2814 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2815 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2816 LookupName(R, S); 2817 CheckShadow(S, D, R); 2818} 2819 2820/// \brief Perform semantic checking on a newly-created variable 2821/// declaration. 2822/// 2823/// This routine performs all of the type-checking required for a 2824/// variable declaration once it has been built. It is used both to 2825/// check variables after they have been parsed and their declarators 2826/// have been translated into a declaration, and to check variables 2827/// that have been instantiated from a template. 2828/// 2829/// Sets NewVD->isInvalidDecl() if an error was encountered. 2830void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2831 LookupResult &Previous, 2832 bool &Redeclaration) { 2833 // If the decl is already known invalid, don't check it. 2834 if (NewVD->isInvalidDecl()) 2835 return; 2836 2837 QualType T = NewVD->getType(); 2838 2839 if (T->isObjCObjectType()) { 2840 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2841 return NewVD->setInvalidDecl(); 2842 } 2843 2844 // Emit an error if an address space was applied to decl with local storage. 2845 // This includes arrays of objects with address space qualifiers, but not 2846 // automatic variables that point to other address spaces. 2847 // ISO/IEC TR 18037 S5.1.2 2848 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2849 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2850 return NewVD->setInvalidDecl(); 2851 } 2852 2853 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2854 && !NewVD->hasAttr<BlocksAttr>()) 2855 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2856 2857 bool isVM = T->isVariablyModifiedType(); 2858 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2859 NewVD->hasAttr<BlocksAttr>()) 2860 setFunctionHasBranchProtectedScope(); 2861 2862 if ((isVM && NewVD->hasLinkage()) || 2863 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2864 bool SizeIsNegative; 2865 QualType FixedTy = 2866 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2867 2868 if (FixedTy.isNull() && T->isVariableArrayType()) { 2869 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2870 // FIXME: This won't give the correct result for 2871 // int a[10][n]; 2872 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2873 2874 if (NewVD->isFileVarDecl()) 2875 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2876 << SizeRange; 2877 else if (NewVD->getStorageClass() == VarDecl::Static) 2878 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2879 << SizeRange; 2880 else 2881 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2882 << SizeRange; 2883 return NewVD->setInvalidDecl(); 2884 } 2885 2886 if (FixedTy.isNull()) { 2887 if (NewVD->isFileVarDecl()) 2888 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2889 else 2890 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2891 return NewVD->setInvalidDecl(); 2892 } 2893 2894 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2895 NewVD->setType(FixedTy); 2896 } 2897 2898 if (Previous.empty() && NewVD->isExternC()) { 2899 // Since we did not find anything by this name and we're declaring 2900 // an extern "C" variable, look for a non-visible extern "C" 2901 // declaration with the same name. 2902 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2903 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2904 if (Pos != LocallyScopedExternalDecls.end()) 2905 Previous.addDecl(Pos->second); 2906 } 2907 2908 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2909 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2910 << T; 2911 return NewVD->setInvalidDecl(); 2912 } 2913 2914 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2915 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2916 return NewVD->setInvalidDecl(); 2917 } 2918 2919 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2920 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2921 return NewVD->setInvalidDecl(); 2922 } 2923 2924 // Function pointers and references cannot have qualified function type, only 2925 // function pointer-to-members can do that. 2926 QualType Pointee; 2927 unsigned PtrOrRef = 0; 2928 if (const PointerType *Ptr = T->getAs<PointerType>()) 2929 Pointee = Ptr->getPointeeType(); 2930 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 2931 Pointee = Ref->getPointeeType(); 2932 PtrOrRef = 1; 2933 } 2934 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 2935 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 2936 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 2937 << PtrOrRef; 2938 return NewVD->setInvalidDecl(); 2939 } 2940 2941 if (!Previous.empty()) { 2942 Redeclaration = true; 2943 MergeVarDecl(NewVD, Previous); 2944 } 2945} 2946 2947/// \brief Data used with FindOverriddenMethod 2948struct FindOverriddenMethodData { 2949 Sema *S; 2950 CXXMethodDecl *Method; 2951}; 2952 2953/// \brief Member lookup function that determines whether a given C++ 2954/// method overrides a method in a base class, to be used with 2955/// CXXRecordDecl::lookupInBases(). 2956static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2957 CXXBasePath &Path, 2958 void *UserData) { 2959 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2960 2961 FindOverriddenMethodData *Data 2962 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2963 2964 DeclarationName Name = Data->Method->getDeclName(); 2965 2966 // FIXME: Do we care about other names here too? 2967 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2968 // We really want to find the base class destructor here. 2969 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2970 CanQualType CT = Data->S->Context.getCanonicalType(T); 2971 2972 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2973 } 2974 2975 for (Path.Decls = BaseRecord->lookup(Name); 2976 Path.Decls.first != Path.Decls.second; 2977 ++Path.Decls.first) { 2978 NamedDecl *D = *Path.Decls.first; 2979 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 2980 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 2981 return true; 2982 } 2983 } 2984 2985 return false; 2986} 2987 2988/// AddOverriddenMethods - See if a method overrides any in the base classes, 2989/// and if so, check that it's a valid override and remember it. 2990void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2991 // Look for virtual methods in base classes that this method might override. 2992 CXXBasePaths Paths; 2993 FindOverriddenMethodData Data; 2994 Data.Method = MD; 2995 Data.S = this; 2996 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2997 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2998 E = Paths.found_decls_end(); I != E; ++I) { 2999 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3000 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3001 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3002 !CheckOverridingFunctionAttributes(MD, OldMD)) 3003 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3004 } 3005 } 3006 } 3007} 3008 3009NamedDecl* 3010Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3011 QualType R, TypeSourceInfo *TInfo, 3012 LookupResult &Previous, 3013 MultiTemplateParamsArg TemplateParamLists, 3014 bool IsFunctionDefinition, bool &Redeclaration) { 3015 assert(R.getTypePtr()->isFunctionType()); 3016 3017 // TODO: consider using NameInfo for diagnostic. 3018 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3019 DeclarationName Name = NameInfo.getName(); 3020 FunctionDecl::StorageClass SC = FunctionDecl::None; 3021 switch (D.getDeclSpec().getStorageClassSpec()) { 3022 default: assert(0 && "Unknown storage class!"); 3023 case DeclSpec::SCS_auto: 3024 case DeclSpec::SCS_register: 3025 case DeclSpec::SCS_mutable: 3026 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3027 diag::err_typecheck_sclass_func); 3028 D.setInvalidType(); 3029 break; 3030 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 3031 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 3032 case DeclSpec::SCS_static: { 3033 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 3034 // C99 6.7.1p5: 3035 // The declaration of an identifier for a function that has 3036 // block scope shall have no explicit storage-class specifier 3037 // other than extern 3038 // See also (C++ [dcl.stc]p4). 3039 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3040 diag::err_static_block_func); 3041 SC = FunctionDecl::None; 3042 } else 3043 SC = FunctionDecl::Static; 3044 break; 3045 } 3046 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 3047 } 3048 3049 if (D.getDeclSpec().isThreadSpecified()) 3050 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3051 3052 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3053 bool isInline = D.getDeclSpec().isInlineSpecified(); 3054 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3055 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3056 3057 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3058 FunctionDecl::StorageClass SCAsWritten 3059 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3060 3061 // Check that the return type is not an abstract class type. 3062 // For record types, this is done by the AbstractClassUsageDiagnoser once 3063 // the class has been completely parsed. 3064 if (!DC->isRecord() && 3065 RequireNonAbstractType(D.getIdentifierLoc(), 3066 R->getAs<FunctionType>()->getResultType(), 3067 diag::err_abstract_type_in_decl, 3068 AbstractReturnType)) 3069 D.setInvalidType(); 3070 3071 // Do not allow returning a objc interface by-value. 3072 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3073 Diag(D.getIdentifierLoc(), 3074 diag::err_object_cannot_be_passed_returned_by_value) << 0 3075 << R->getAs<FunctionType>()->getResultType(); 3076 D.setInvalidType(); 3077 } 3078 3079 bool isVirtualOkay = false; 3080 FunctionDecl *NewFD; 3081 3082 if (isFriend) { 3083 // C++ [class.friend]p5 3084 // A function can be defined in a friend declaration of a 3085 // class . . . . Such a function is implicitly inline. 3086 isInline |= IsFunctionDefinition; 3087 } 3088 3089 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3090 // This is a C++ constructor declaration. 3091 assert(DC->isRecord() && 3092 "Constructors can only be declared in a member context"); 3093 3094 R = CheckConstructorDeclarator(D, R, SC); 3095 3096 // Create the new declaration 3097 NewFD = CXXConstructorDecl::Create(Context, 3098 cast<CXXRecordDecl>(DC), 3099 NameInfo, R, TInfo, 3100 isExplicit, isInline, 3101 /*isImplicitlyDeclared=*/false); 3102 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3103 // This is a C++ destructor declaration. 3104 if (DC->isRecord()) { 3105 R = CheckDestructorDeclarator(D, R, SC); 3106 3107 NewFD = CXXDestructorDecl::Create(Context, 3108 cast<CXXRecordDecl>(DC), 3109 NameInfo, R, 3110 isInline, 3111 /*isImplicitlyDeclared=*/false); 3112 NewFD->setTypeSourceInfo(TInfo); 3113 3114 isVirtualOkay = true; 3115 } else { 3116 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3117 3118 // Create a FunctionDecl to satisfy the function definition parsing 3119 // code path. 3120 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3121 Name, R, TInfo, SC, SCAsWritten, isInline, 3122 /*hasPrototype=*/true); 3123 D.setInvalidType(); 3124 } 3125 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3126 if (!DC->isRecord()) { 3127 Diag(D.getIdentifierLoc(), 3128 diag::err_conv_function_not_member); 3129 return 0; 3130 } 3131 3132 CheckConversionDeclarator(D, R, SC); 3133 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3134 NameInfo, R, TInfo, 3135 isInline, isExplicit); 3136 3137 isVirtualOkay = true; 3138 } else if (DC->isRecord()) { 3139 // If the of the function is the same as the name of the record, then this 3140 // must be an invalid constructor that has a return type. 3141 // (The parser checks for a return type and makes the declarator a 3142 // constructor if it has no return type). 3143 // must have an invalid constructor that has a return type 3144 if (Name.getAsIdentifierInfo() && 3145 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3146 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3147 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3148 << SourceRange(D.getIdentifierLoc()); 3149 return 0; 3150 } 3151 3152 bool isStatic = SC == FunctionDecl::Static; 3153 3154 // [class.free]p1: 3155 // Any allocation function for a class T is a static member 3156 // (even if not explicitly declared static). 3157 if (Name.getCXXOverloadedOperator() == OO_New || 3158 Name.getCXXOverloadedOperator() == OO_Array_New) 3159 isStatic = true; 3160 3161 // [class.free]p6 Any deallocation function for a class X is a static member 3162 // (even if not explicitly declared static). 3163 if (Name.getCXXOverloadedOperator() == OO_Delete || 3164 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3165 isStatic = true; 3166 3167 // This is a C++ method declaration. 3168 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3169 NameInfo, R, TInfo, 3170 isStatic, SCAsWritten, isInline); 3171 3172 isVirtualOkay = !isStatic; 3173 } else { 3174 // Determine whether the function was written with a 3175 // prototype. This true when: 3176 // - we're in C++ (where every function has a prototype), 3177 // - there is a prototype in the declarator, or 3178 // - the type R of the function is some kind of typedef or other reference 3179 // to a type name (which eventually refers to a function type). 3180 bool HasPrototype = 3181 getLangOptions().CPlusPlus || 3182 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3183 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3184 3185 NewFD = FunctionDecl::Create(Context, DC, 3186 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3187 HasPrototype); 3188 } 3189 3190 if (D.isInvalidType()) 3191 NewFD->setInvalidDecl(); 3192 3193 SetNestedNameSpecifier(NewFD, D); 3194 3195 // Set the lexical context. If the declarator has a C++ 3196 // scope specifier, or is the object of a friend declaration, the 3197 // lexical context will be different from the semantic context. 3198 NewFD->setLexicalDeclContext(CurContext); 3199 3200 // Match up the template parameter lists with the scope specifier, then 3201 // determine whether we have a template or a template specialization. 3202 FunctionTemplateDecl *FunctionTemplate = 0; 3203 bool isExplicitSpecialization = false; 3204 bool isFunctionTemplateSpecialization = false; 3205 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3206 bool Invalid = false; 3207 if (TemplateParameterList *TemplateParams 3208 = MatchTemplateParametersToScopeSpecifier( 3209 D.getDeclSpec().getSourceRange().getBegin(), 3210 D.getCXXScopeSpec(), 3211 (TemplateParameterList**)TemplateParamLists.get(), 3212 TemplateParamLists.size(), 3213 isFriend, 3214 isExplicitSpecialization, 3215 Invalid)) { 3216 // All but one template parameter lists have been matching. 3217 --NumMatchedTemplateParamLists; 3218 3219 if (TemplateParams->size() > 0) { 3220 // This is a function template 3221 3222 // Check that we can declare a template here. 3223 if (CheckTemplateDeclScope(S, TemplateParams)) 3224 return 0; 3225 3226 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3227 NewFD->getLocation(), 3228 Name, TemplateParams, 3229 NewFD); 3230 FunctionTemplate->setLexicalDeclContext(CurContext); 3231 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3232 } else { 3233 // This is a function template specialization. 3234 isFunctionTemplateSpecialization = true; 3235 3236 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3237 if (isFriend && isFunctionTemplateSpecialization) { 3238 // We want to remove the "template<>", found here. 3239 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3240 3241 // If we remove the template<> and the name is not a 3242 // template-id, we're actually silently creating a problem: 3243 // the friend declaration will refer to an untemplated decl, 3244 // and clearly the user wants a template specialization. So 3245 // we need to insert '<>' after the name. 3246 SourceLocation InsertLoc; 3247 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3248 InsertLoc = D.getName().getSourceRange().getEnd(); 3249 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3250 } 3251 3252 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3253 << Name << RemoveRange 3254 << FixItHint::CreateRemoval(RemoveRange) 3255 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3256 } 3257 } 3258 } 3259 3260 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3261 NewFD->setTemplateParameterListsInfo(Context, 3262 NumMatchedTemplateParamLists, 3263 (TemplateParameterList**)TemplateParamLists.release()); 3264 } 3265 3266 if (Invalid) { 3267 NewFD->setInvalidDecl(); 3268 if (FunctionTemplate) 3269 FunctionTemplate->setInvalidDecl(); 3270 } 3271 3272 // C++ [dcl.fct.spec]p5: 3273 // The virtual specifier shall only be used in declarations of 3274 // nonstatic class member functions that appear within a 3275 // member-specification of a class declaration; see 10.3. 3276 // 3277 if (isVirtual && !NewFD->isInvalidDecl()) { 3278 if (!isVirtualOkay) { 3279 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3280 diag::err_virtual_non_function); 3281 } else if (!CurContext->isRecord()) { 3282 // 'virtual' was specified outside of the class. 3283 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3284 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3285 } else { 3286 // Okay: Add virtual to the method. 3287 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3288 CurClass->setMethodAsVirtual(NewFD); 3289 } 3290 } 3291 3292 // C++ [dcl.fct.spec]p3: 3293 // The inline specifier shall not appear on a block scope function declaration. 3294 if (isInline && !NewFD->isInvalidDecl() && getLangOptions().CPlusPlus) { 3295 if (CurContext->isFunctionOrMethod()) { 3296 // 'inline' is not allowed on block scope function declaration. 3297 Diag(D.getDeclSpec().getInlineSpecLoc(), 3298 diag::err_inline_declaration_block_scope) << Name 3299 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3300 } 3301 } 3302 3303 // C++ [dcl.fct.spec]p6: 3304 // The explicit specifier shall be used only in the declaration of a 3305 // constructor or conversion function within its class definition; see 12.3.1 3306 // and 12.3.2. 3307 if (isExplicit && !NewFD->isInvalidDecl()) { 3308 if (!CurContext->isRecord()) { 3309 // 'explicit' was specified outside of the class. 3310 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3311 diag::err_explicit_out_of_class) 3312 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3313 } else if (!isa<CXXConstructorDecl>(NewFD) && 3314 !isa<CXXConversionDecl>(NewFD)) { 3315 // 'explicit' was specified on a function that wasn't a constructor 3316 // or conversion function. 3317 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3318 diag::err_explicit_non_ctor_or_conv_function) 3319 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3320 } 3321 } 3322 3323 // Filter out previous declarations that don't match the scope. 3324 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3325 3326 if (isFriend) { 3327 // DC is the namespace in which the function is being declared. 3328 assert((DC->isFileContext() || !Previous.empty()) && 3329 "previously-undeclared friend function being created " 3330 "in a non-namespace context"); 3331 3332 // For now, claim that the objects have no previous declaration. 3333 if (FunctionTemplate) { 3334 FunctionTemplate->setObjectOfFriendDecl(false); 3335 FunctionTemplate->setAccess(AS_public); 3336 } 3337 NewFD->setObjectOfFriendDecl(false); 3338 NewFD->setAccess(AS_public); 3339 } 3340 3341 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3342 !CurContext->isRecord()) { 3343 // C++ [class.static]p1: 3344 // A data or function member of a class may be declared static 3345 // in a class definition, in which case it is a static member of 3346 // the class. 3347 3348 // Complain about the 'static' specifier if it's on an out-of-line 3349 // member function definition. 3350 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3351 diag::err_static_out_of_line) 3352 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3353 } 3354 3355 // Handle GNU asm-label extension (encoded as an attribute). 3356 if (Expr *E = (Expr*) D.getAsmLabel()) { 3357 // The parser guarantees this is a string. 3358 StringLiteral *SE = cast<StringLiteral>(E); 3359 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3360 } 3361 3362 // Copy the parameter declarations from the declarator D to the function 3363 // declaration NewFD, if they are available. First scavenge them into Params. 3364 llvm::SmallVector<ParmVarDecl*, 16> Params; 3365 if (D.getNumTypeObjects() > 0) { 3366 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3367 3368 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3369 // function that takes no arguments, not a function that takes a 3370 // single void argument. 3371 // We let through "const void" here because Sema::GetTypeForDeclarator 3372 // already checks for that case. 3373 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3374 FTI.ArgInfo[0].Param && 3375 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3376 // Empty arg list, don't push any params. 3377 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3378 3379 // In C++, the empty parameter-type-list must be spelled "void"; a 3380 // typedef of void is not permitted. 3381 if (getLangOptions().CPlusPlus && 3382 Param->getType().getUnqualifiedType() != Context.VoidTy) 3383 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3384 // FIXME: Leaks decl? 3385 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3386 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3387 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3388 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3389 Param->setDeclContext(NewFD); 3390 Params.push_back(Param); 3391 3392 if (Param->isInvalidDecl()) 3393 NewFD->setInvalidDecl(); 3394 } 3395 } 3396 3397 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3398 // When we're declaring a function with a typedef, typeof, etc as in the 3399 // following example, we'll need to synthesize (unnamed) 3400 // parameters for use in the declaration. 3401 // 3402 // @code 3403 // typedef void fn(int); 3404 // fn f; 3405 // @endcode 3406 3407 // Synthesize a parameter for each argument type. 3408 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3409 AE = FT->arg_type_end(); AI != AE; ++AI) { 3410 ParmVarDecl *Param = 3411 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3412 Params.push_back(Param); 3413 } 3414 } else { 3415 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3416 "Should not need args for typedef of non-prototype fn"); 3417 } 3418 // Finally, we know we have the right number of parameters, install them. 3419 NewFD->setParams(Params.data(), Params.size()); 3420 3421 // If the declarator is a template-id, translate the parser's template 3422 // argument list into our AST format. 3423 bool HasExplicitTemplateArgs = false; 3424 TemplateArgumentListInfo TemplateArgs; 3425 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3426 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3427 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3428 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3429 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3430 TemplateId->getTemplateArgs(), 3431 TemplateId->NumArgs); 3432 translateTemplateArguments(TemplateArgsPtr, 3433 TemplateArgs); 3434 TemplateArgsPtr.release(); 3435 3436 HasExplicitTemplateArgs = true; 3437 3438 if (FunctionTemplate) { 3439 // FIXME: Diagnose function template with explicit template 3440 // arguments. 3441 HasExplicitTemplateArgs = false; 3442 } else if (!isFunctionTemplateSpecialization && 3443 !D.getDeclSpec().isFriendSpecified()) { 3444 // We have encountered something that the user meant to be a 3445 // specialization (because it has explicitly-specified template 3446 // arguments) but that was not introduced with a "template<>" (or had 3447 // too few of them). 3448 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3449 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3450 << FixItHint::CreateInsertion( 3451 D.getDeclSpec().getSourceRange().getBegin(), 3452 "template<> "); 3453 isFunctionTemplateSpecialization = true; 3454 } else { 3455 // "friend void foo<>(int);" is an implicit specialization decl. 3456 isFunctionTemplateSpecialization = true; 3457 } 3458 } else if (isFriend && isFunctionTemplateSpecialization) { 3459 // This combination is only possible in a recovery case; the user 3460 // wrote something like: 3461 // template <> friend void foo(int); 3462 // which we're recovering from as if the user had written: 3463 // friend void foo<>(int); 3464 // Go ahead and fake up a template id. 3465 HasExplicitTemplateArgs = true; 3466 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3467 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3468 } 3469 3470 // If it's a friend (and only if it's a friend), it's possible 3471 // that either the specialized function type or the specialized 3472 // template is dependent, and therefore matching will fail. In 3473 // this case, don't check the specialization yet. 3474 if (isFunctionTemplateSpecialization && isFriend && 3475 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3476 assert(HasExplicitTemplateArgs && 3477 "friend function specialization without template args"); 3478 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3479 Previous)) 3480 NewFD->setInvalidDecl(); 3481 } else if (isFunctionTemplateSpecialization) { 3482 if (CheckFunctionTemplateSpecialization(NewFD, 3483 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3484 Previous)) 3485 NewFD->setInvalidDecl(); 3486 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3487 if (CheckMemberSpecialization(NewFD, Previous)) 3488 NewFD->setInvalidDecl(); 3489 } 3490 3491 // Perform semantic checking on the function declaration. 3492 bool OverloadableAttrRequired = false; // FIXME: HACK! 3493 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3494 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3495 3496 assert((NewFD->isInvalidDecl() || !Redeclaration || 3497 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3498 "previous declaration set still overloaded"); 3499 3500 NamedDecl *PrincipalDecl = (FunctionTemplate 3501 ? cast<NamedDecl>(FunctionTemplate) 3502 : NewFD); 3503 3504 if (isFriend && Redeclaration) { 3505 AccessSpecifier Access = AS_public; 3506 if (!NewFD->isInvalidDecl()) 3507 Access = NewFD->getPreviousDeclaration()->getAccess(); 3508 3509 NewFD->setAccess(Access); 3510 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3511 3512 PrincipalDecl->setObjectOfFriendDecl(true); 3513 } 3514 3515 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3516 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3517 PrincipalDecl->setNonMemberOperator(); 3518 3519 // If we have a function template, check the template parameter 3520 // list. This will check and merge default template arguments. 3521 if (FunctionTemplate) { 3522 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3523 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3524 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3525 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3526 : TPC_FunctionTemplate); 3527 } 3528 3529 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3530 // Fake up an access specifier if it's supposed to be a class member. 3531 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3532 NewFD->setAccess(AS_public); 3533 3534 // An out-of-line member function declaration must also be a 3535 // definition (C++ [dcl.meaning]p1). 3536 // Note that this is not the case for explicit specializations of 3537 // function templates or member functions of class templates, per 3538 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3539 // for compatibility with old SWIG code which likes to generate them. 3540 if (!IsFunctionDefinition && !isFriend && 3541 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3542 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3543 << D.getCXXScopeSpec().getRange(); 3544 } 3545 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3546 // The user tried to provide an out-of-line definition for a 3547 // function that is a member of a class or namespace, but there 3548 // was no such member function declared (C++ [class.mfct]p2, 3549 // C++ [namespace.memdef]p2). For example: 3550 // 3551 // class X { 3552 // void f() const; 3553 // }; 3554 // 3555 // void X::f() { } // ill-formed 3556 // 3557 // Complain about this problem, and attempt to suggest close 3558 // matches (e.g., those that differ only in cv-qualifiers and 3559 // whether the parameter types are references). 3560 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3561 << Name << DC << D.getCXXScopeSpec().getRange(); 3562 NewFD->setInvalidDecl(); 3563 3564 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3565 ForRedeclaration); 3566 LookupQualifiedName(Prev, DC); 3567 assert(!Prev.isAmbiguous() && 3568 "Cannot have an ambiguity in previous-declaration lookup"); 3569 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3570 Func != FuncEnd; ++Func) { 3571 if (isa<FunctionDecl>(*Func) && 3572 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3573 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3574 } 3575 } 3576 } 3577 3578 // Handle attributes. We need to have merged decls when handling attributes 3579 // (for example to check for conflicts, etc). 3580 // FIXME: This needs to happen before we merge declarations. Then, 3581 // let attribute merging cope with attribute conflicts. 3582 ProcessDeclAttributes(S, NewFD, D); 3583 3584 // attributes declared post-definition are currently ignored 3585 if (Redeclaration && Previous.isSingleResult()) { 3586 const FunctionDecl *Def; 3587 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3588 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3589 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3590 Diag(Def->getLocation(), diag::note_previous_definition); 3591 } 3592 } 3593 3594 AddKnownFunctionAttributes(NewFD); 3595 3596 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3597 // If a function name is overloadable in C, then every function 3598 // with that name must be marked "overloadable". 3599 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3600 << Redeclaration << NewFD; 3601 if (!Previous.empty()) 3602 Diag(Previous.getRepresentativeDecl()->getLocation(), 3603 diag::note_attribute_overloadable_prev_overload); 3604 NewFD->addAttr(::new (Context) OverloadableAttr()); 3605 } 3606 3607 if (NewFD->hasAttr<OverloadableAttr>() && 3608 !NewFD->getType()->getAs<FunctionProtoType>()) { 3609 Diag(NewFD->getLocation(), 3610 diag::err_attribute_overloadable_no_prototype) 3611 << NewFD; 3612 3613 // Turn this into a variadic function with no parameters. 3614 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 3615 QualType R = Context.getFunctionType(FT->getResultType(), 3616 0, 0, true, 0, false, false, 0, 0, 3617 FT->getExtInfo()); 3618 NewFD->setType(R); 3619 } 3620 3621 // If there's a #pragma GCC visibility in scope, and this isn't a class 3622 // member, set the visibility of this function. 3623 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3624 AddPushedVisibilityAttribute(NewFD); 3625 3626 // If this is a locally-scoped extern C function, update the 3627 // map of such names. 3628 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3629 && !NewFD->isInvalidDecl()) 3630 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3631 3632 // Set this FunctionDecl's range up to the right paren. 3633 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3634 3635 if (FunctionTemplate && NewFD->isInvalidDecl()) 3636 FunctionTemplate->setInvalidDecl(); 3637 3638 if (FunctionTemplate) 3639 return FunctionTemplate; 3640 3641 if (IsFunctionDefinition) 3642 MarkUnusedFileScopedDecl(NewFD); 3643 3644 return NewFD; 3645} 3646 3647/// \brief Perform semantic checking of a new function declaration. 3648/// 3649/// Performs semantic analysis of the new function declaration 3650/// NewFD. This routine performs all semantic checking that does not 3651/// require the actual declarator involved in the declaration, and is 3652/// used both for the declaration of functions as they are parsed 3653/// (called via ActOnDeclarator) and for the declaration of functions 3654/// that have been instantiated via C++ template instantiation (called 3655/// via InstantiateDecl). 3656/// 3657/// \param IsExplicitSpecialiation whether this new function declaration is 3658/// an explicit specialization of the previous declaration. 3659/// 3660/// This sets NewFD->isInvalidDecl() to true if there was an error. 3661void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3662 LookupResult &Previous, 3663 bool IsExplicitSpecialization, 3664 bool &Redeclaration, 3665 bool &OverloadableAttrRequired) { 3666 // If NewFD is already known erroneous, don't do any of this checking. 3667 if (NewFD->isInvalidDecl()) { 3668 // If this is a class member, mark the class invalid immediately. 3669 // This avoids some consistency errors later. 3670 if (isa<CXXMethodDecl>(NewFD)) 3671 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 3672 3673 return; 3674 } 3675 3676 if (NewFD->getResultType()->isVariablyModifiedType()) { 3677 // Functions returning a variably modified type violate C99 6.7.5.2p2 3678 // because all functions have linkage. 3679 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3680 return NewFD->setInvalidDecl(); 3681 } 3682 3683 if (NewFD->isMain()) 3684 CheckMain(NewFD); 3685 3686 // Check for a previous declaration of this name. 3687 if (Previous.empty() && NewFD->isExternC()) { 3688 // Since we did not find anything by this name and we're declaring 3689 // an extern "C" function, look for a non-visible extern "C" 3690 // declaration with the same name. 3691 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3692 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3693 if (Pos != LocallyScopedExternalDecls.end()) 3694 Previous.addDecl(Pos->second); 3695 } 3696 3697 // Merge or overload the declaration with an existing declaration of 3698 // the same name, if appropriate. 3699 if (!Previous.empty()) { 3700 // Determine whether NewFD is an overload of PrevDecl or 3701 // a declaration that requires merging. If it's an overload, 3702 // there's no more work to do here; we'll just add the new 3703 // function to the scope. 3704 3705 NamedDecl *OldDecl = 0; 3706 if (!AllowOverloadingOfFunction(Previous, Context)) { 3707 Redeclaration = true; 3708 OldDecl = Previous.getFoundDecl(); 3709 } else { 3710 if (!getLangOptions().CPlusPlus) 3711 OverloadableAttrRequired = true; 3712 3713 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3714 /*NewIsUsingDecl*/ false)) { 3715 case Ovl_Match: 3716 Redeclaration = true; 3717 break; 3718 3719 case Ovl_NonFunction: 3720 Redeclaration = true; 3721 break; 3722 3723 case Ovl_Overload: 3724 Redeclaration = false; 3725 break; 3726 } 3727 } 3728 3729 if (Redeclaration) { 3730 // NewFD and OldDecl represent declarations that need to be 3731 // merged. 3732 if (MergeFunctionDecl(NewFD, OldDecl)) 3733 return NewFD->setInvalidDecl(); 3734 3735 Previous.clear(); 3736 Previous.addDecl(OldDecl); 3737 3738 if (FunctionTemplateDecl *OldTemplateDecl 3739 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3740 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3741 FunctionTemplateDecl *NewTemplateDecl 3742 = NewFD->getDescribedFunctionTemplate(); 3743 assert(NewTemplateDecl && "Template/non-template mismatch"); 3744 if (CXXMethodDecl *Method 3745 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3746 Method->setAccess(OldTemplateDecl->getAccess()); 3747 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3748 } 3749 3750 // If this is an explicit specialization of a member that is a function 3751 // template, mark it as a member specialization. 3752 if (IsExplicitSpecialization && 3753 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3754 NewTemplateDecl->setMemberSpecialization(); 3755 assert(OldTemplateDecl->isMemberSpecialization()); 3756 } 3757 } else { 3758 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3759 NewFD->setAccess(OldDecl->getAccess()); 3760 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3761 } 3762 } 3763 } 3764 3765 // Semantic checking for this function declaration (in isolation). 3766 if (getLangOptions().CPlusPlus) { 3767 // C++-specific checks. 3768 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3769 CheckConstructor(Constructor); 3770 } else if (CXXDestructorDecl *Destructor = 3771 dyn_cast<CXXDestructorDecl>(NewFD)) { 3772 CXXRecordDecl *Record = Destructor->getParent(); 3773 QualType ClassType = Context.getTypeDeclType(Record); 3774 3775 // FIXME: Shouldn't we be able to perform this check even when the class 3776 // type is dependent? Both gcc and edg can handle that. 3777 if (!ClassType->isDependentType()) { 3778 DeclarationName Name 3779 = Context.DeclarationNames.getCXXDestructorName( 3780 Context.getCanonicalType(ClassType)); 3781// NewFD->getDeclName().dump(); 3782// Name.dump(); 3783 if (NewFD->getDeclName() != Name) { 3784 Diag(NewFD->getLocation(), diag::err_destructor_name); 3785 return NewFD->setInvalidDecl(); 3786 } 3787 } 3788 3789 Record->setUserDeclaredDestructor(true); 3790 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3791 // user-defined destructor. 3792 Record->setPOD(false); 3793 3794 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3795 // declared destructor. 3796 // FIXME: C++0x: don't do this for "= default" destructors 3797 Record->setHasTrivialDestructor(false); 3798 } else if (CXXConversionDecl *Conversion 3799 = dyn_cast<CXXConversionDecl>(NewFD)) { 3800 ActOnConversionDeclarator(Conversion); 3801 } 3802 3803 // Find any virtual functions that this function overrides. 3804 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3805 if (!Method->isFunctionTemplateSpecialization() && 3806 !Method->getDescribedFunctionTemplate()) 3807 AddOverriddenMethods(Method->getParent(), Method); 3808 } 3809 3810 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3811 if (NewFD->isOverloadedOperator() && 3812 CheckOverloadedOperatorDeclaration(NewFD)) 3813 return NewFD->setInvalidDecl(); 3814 3815 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3816 if (NewFD->getLiteralIdentifier() && 3817 CheckLiteralOperatorDeclaration(NewFD)) 3818 return NewFD->setInvalidDecl(); 3819 3820 // In C++, check default arguments now that we have merged decls. Unless 3821 // the lexical context is the class, because in this case this is done 3822 // during delayed parsing anyway. 3823 if (!CurContext->isRecord()) 3824 CheckCXXDefaultArguments(NewFD); 3825 } 3826} 3827 3828void Sema::CheckMain(FunctionDecl* FD) { 3829 // C++ [basic.start.main]p3: A program that declares main to be inline 3830 // or static is ill-formed. 3831 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3832 // shall not appear in a declaration of main. 3833 // static main is not an error under C99, but we should warn about it. 3834 bool isInline = FD->isInlineSpecified(); 3835 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3836 if (isInline || isStatic) { 3837 unsigned diagID = diag::warn_unusual_main_decl; 3838 if (isInline || getLangOptions().CPlusPlus) 3839 diagID = diag::err_unusual_main_decl; 3840 3841 int which = isStatic + (isInline << 1) - 1; 3842 Diag(FD->getLocation(), diagID) << which; 3843 } 3844 3845 QualType T = FD->getType(); 3846 assert(T->isFunctionType() && "function decl is not of function type"); 3847 const FunctionType* FT = T->getAs<FunctionType>(); 3848 3849 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3850 // TODO: add a replacement fixit to turn the return type into 'int'. 3851 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3852 FD->setInvalidDecl(true); 3853 } 3854 3855 // Treat protoless main() as nullary. 3856 if (isa<FunctionNoProtoType>(FT)) return; 3857 3858 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3859 unsigned nparams = FTP->getNumArgs(); 3860 assert(FD->getNumParams() == nparams); 3861 3862 bool HasExtraParameters = (nparams > 3); 3863 3864 // Darwin passes an undocumented fourth argument of type char**. If 3865 // other platforms start sprouting these, the logic below will start 3866 // getting shifty. 3867 if (nparams == 4 && 3868 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3869 HasExtraParameters = false; 3870 3871 if (HasExtraParameters) { 3872 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3873 FD->setInvalidDecl(true); 3874 nparams = 3; 3875 } 3876 3877 // FIXME: a lot of the following diagnostics would be improved 3878 // if we had some location information about types. 3879 3880 QualType CharPP = 3881 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3882 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3883 3884 for (unsigned i = 0; i < nparams; ++i) { 3885 QualType AT = FTP->getArgType(i); 3886 3887 bool mismatch = true; 3888 3889 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3890 mismatch = false; 3891 else if (Expected[i] == CharPP) { 3892 // As an extension, the following forms are okay: 3893 // char const ** 3894 // char const * const * 3895 // char * const * 3896 3897 QualifierCollector qs; 3898 const PointerType* PT; 3899 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3900 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3901 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3902 qs.removeConst(); 3903 mismatch = !qs.empty(); 3904 } 3905 } 3906 3907 if (mismatch) { 3908 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3909 // TODO: suggest replacing given type with expected type 3910 FD->setInvalidDecl(true); 3911 } 3912 } 3913 3914 if (nparams == 1 && !FD->isInvalidDecl()) { 3915 Diag(FD->getLocation(), diag::warn_main_one_arg); 3916 } 3917} 3918 3919bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3920 // FIXME: Need strict checking. In C89, we need to check for 3921 // any assignment, increment, decrement, function-calls, or 3922 // commas outside of a sizeof. In C99, it's the same list, 3923 // except that the aforementioned are allowed in unevaluated 3924 // expressions. Everything else falls under the 3925 // "may accept other forms of constant expressions" exception. 3926 // (We never end up here for C++, so the constant expression 3927 // rules there don't matter.) 3928 if (Init->isConstantInitializer(Context, false)) 3929 return false; 3930 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3931 << Init->getSourceRange(); 3932 return true; 3933} 3934 3935void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3936 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3937} 3938 3939/// AddInitializerToDecl - Adds the initializer Init to the 3940/// declaration dcl. If DirectInit is true, this is C++ direct 3941/// initialization rather than copy initialization. 3942void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3943 Decl *RealDecl = dcl.getAs<Decl>(); 3944 // If there is no declaration, there was an error parsing it. Just ignore 3945 // the initializer. 3946 if (RealDecl == 0) 3947 return; 3948 3949 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3950 // With declarators parsed the way they are, the parser cannot 3951 // distinguish between a normal initializer and a pure-specifier. 3952 // Thus this grotesque test. 3953 IntegerLiteral *IL; 3954 Expr *Init = static_cast<Expr *>(init.get()); 3955 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3956 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3957 CheckPureMethod(Method, Init->getSourceRange()); 3958 else { 3959 Diag(Method->getLocation(), diag::err_member_function_initialization) 3960 << Method->getDeclName() << Init->getSourceRange(); 3961 Method->setInvalidDecl(); 3962 } 3963 return; 3964 } 3965 3966 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3967 if (!VDecl) { 3968 if (getLangOptions().CPlusPlus && 3969 RealDecl->getLexicalDeclContext()->isRecord() && 3970 isa<NamedDecl>(RealDecl)) 3971 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3972 << cast<NamedDecl>(RealDecl)->getDeclName(); 3973 else 3974 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3975 RealDecl->setInvalidDecl(); 3976 return; 3977 } 3978 3979 // A definition must end up with a complete type, which means it must be 3980 // complete with the restriction that an array type might be completed by the 3981 // initializer; note that later code assumes this restriction. 3982 QualType BaseDeclType = VDecl->getType(); 3983 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3984 BaseDeclType = Array->getElementType(); 3985 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3986 diag::err_typecheck_decl_incomplete_type)) { 3987 RealDecl->setInvalidDecl(); 3988 return; 3989 } 3990 3991 // The variable can not have an abstract class type. 3992 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3993 diag::err_abstract_type_in_decl, 3994 AbstractVariableType)) 3995 VDecl->setInvalidDecl(); 3996 3997 const VarDecl *Def; 3998 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3999 Diag(VDecl->getLocation(), diag::err_redefinition) 4000 << VDecl->getDeclName(); 4001 Diag(Def->getLocation(), diag::note_previous_definition); 4002 VDecl->setInvalidDecl(); 4003 return; 4004 } 4005 4006 if (getLangOptions().CPlusPlus && VDecl->hasLocalStorage()) 4007 setFunctionHasBranchProtectedScope(); 4008 4009 // Take ownership of the expression, now that we're sure we have somewhere 4010 // to put it. 4011 Expr *Init = init.takeAs<Expr>(); 4012 assert(Init && "missing initializer"); 4013 4014 // Capture the variable that is being initialized and the style of 4015 // initialization. 4016 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4017 4018 // FIXME: Poor source location information. 4019 InitializationKind Kind 4020 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4021 Init->getLocStart(), 4022 Init->getLocEnd()) 4023 : InitializationKind::CreateCopy(VDecl->getLocation(), 4024 Init->getLocStart()); 4025 4026 // Get the decls type and save a reference for later, since 4027 // CheckInitializerTypes may change it. 4028 QualType DclT = VDecl->getType(), SavT = DclT; 4029 if (VDecl->isBlockVarDecl()) { 4030 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4031 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4032 VDecl->setInvalidDecl(); 4033 } else if (!VDecl->isInvalidDecl()) { 4034 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4035 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4036 MultiExprArg(*this, (void**)&Init, 1), 4037 &DclT); 4038 if (Result.isInvalid()) { 4039 VDecl->setInvalidDecl(); 4040 return; 4041 } 4042 4043 Init = Result.takeAs<Expr>(); 4044 4045 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4046 // Don't check invalid declarations to avoid emitting useless diagnostics. 4047 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4048 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 4049 CheckForConstantInitializer(Init, DclT); 4050 } 4051 } 4052 } else if (VDecl->isStaticDataMember() && 4053 VDecl->getLexicalDeclContext()->isRecord()) { 4054 // This is an in-class initialization for a static data member, e.g., 4055 // 4056 // struct S { 4057 // static const int value = 17; 4058 // }; 4059 4060 // Attach the initializer 4061 VDecl->setInit(Init); 4062 4063 // C++ [class.mem]p4: 4064 // A member-declarator can contain a constant-initializer only 4065 // if it declares a static member (9.4) of const integral or 4066 // const enumeration type, see 9.4.2. 4067 QualType T = VDecl->getType(); 4068 if (!T->isDependentType() && 4069 (!Context.getCanonicalType(T).isConstQualified() || 4070 !T->isIntegralOrEnumerationType())) { 4071 Diag(VDecl->getLocation(), diag::err_member_initialization) 4072 << VDecl->getDeclName() << Init->getSourceRange(); 4073 VDecl->setInvalidDecl(); 4074 } else { 4075 // C++ [class.static.data]p4: 4076 // If a static data member is of const integral or const 4077 // enumeration type, its declaration in the class definition 4078 // can specify a constant-initializer which shall be an 4079 // integral constant expression (5.19). 4080 if (!Init->isTypeDependent() && 4081 !Init->getType()->isIntegralOrEnumerationType()) { 4082 // We have a non-dependent, non-integral or enumeration type. 4083 Diag(Init->getSourceRange().getBegin(), 4084 diag::err_in_class_initializer_non_integral_type) 4085 << Init->getType() << Init->getSourceRange(); 4086 VDecl->setInvalidDecl(); 4087 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4088 // Check whether the expression is a constant expression. 4089 llvm::APSInt Value; 4090 SourceLocation Loc; 4091 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4092 Diag(Loc, diag::err_in_class_initializer_non_constant) 4093 << Init->getSourceRange(); 4094 VDecl->setInvalidDecl(); 4095 } else if (!VDecl->getType()->isDependentType()) 4096 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4097 } 4098 } 4099 } else if (VDecl->isFileVarDecl()) { 4100 if (VDecl->getStorageClass() == VarDecl::Extern && 4101 (!getLangOptions().CPlusPlus || 4102 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4103 Diag(VDecl->getLocation(), diag::warn_extern_init); 4104 if (!VDecl->isInvalidDecl()) { 4105 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4106 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4107 MultiExprArg(*this, (void**)&Init, 1), 4108 &DclT); 4109 if (Result.isInvalid()) { 4110 VDecl->setInvalidDecl(); 4111 return; 4112 } 4113 4114 Init = Result.takeAs<Expr>(); 4115 } 4116 4117 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4118 // Don't check invalid declarations to avoid emitting useless diagnostics. 4119 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4120 // C99 6.7.8p4. All file scoped initializers need to be constant. 4121 CheckForConstantInitializer(Init, DclT); 4122 } 4123 } 4124 // If the type changed, it means we had an incomplete type that was 4125 // completed by the initializer. For example: 4126 // int ary[] = { 1, 3, 5 }; 4127 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4128 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4129 VDecl->setType(DclT); 4130 Init->setType(DclT); 4131 } 4132 4133 Init = MaybeCreateCXXExprWithTemporaries(Init); 4134 // Attach the initializer to the decl. 4135 VDecl->setInit(Init); 4136 4137 if (getLangOptions().CPlusPlus) { 4138 if (!VDecl->isInvalidDecl() && 4139 !VDecl->getDeclContext()->isDependentContext() && 4140 VDecl->hasGlobalStorage() && 4141 !Init->isConstantInitializer(Context, 4142 VDecl->getType()->isReferenceType())) 4143 Diag(VDecl->getLocation(), diag::warn_global_constructor) 4144 << Init->getSourceRange(); 4145 4146 // Make sure we mark the destructor as used if necessary. 4147 QualType InitType = VDecl->getType(); 4148 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4149 InitType = Context.getBaseElementType(Array); 4150 if (const RecordType *Record = InitType->getAs<RecordType>()) 4151 FinalizeVarWithDestructor(VDecl, Record); 4152 } 4153 4154 return; 4155} 4156 4157/// ActOnInitializerError - Given that there was an error parsing an 4158/// initializer for the given declaration, try to return to some form 4159/// of sanity. 4160void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4161 // Our main concern here is re-establishing invariants like "a 4162 // variable's type is either dependent or complete". 4163 Decl *D = dcl.getAs<Decl>(); 4164 if (!D || D->isInvalidDecl()) return; 4165 4166 VarDecl *VD = dyn_cast<VarDecl>(D); 4167 if (!VD) return; 4168 4169 QualType Ty = VD->getType(); 4170 if (Ty->isDependentType()) return; 4171 4172 // Require a complete type. 4173 if (RequireCompleteType(VD->getLocation(), 4174 Context.getBaseElementType(Ty), 4175 diag::err_typecheck_decl_incomplete_type)) { 4176 VD->setInvalidDecl(); 4177 return; 4178 } 4179 4180 // Require an abstract type. 4181 if (RequireNonAbstractType(VD->getLocation(), Ty, 4182 diag::err_abstract_type_in_decl, 4183 AbstractVariableType)) { 4184 VD->setInvalidDecl(); 4185 return; 4186 } 4187 4188 // Don't bother complaining about constructors or destructors, 4189 // though. 4190} 4191 4192void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4193 bool TypeContainsUndeducedAuto) { 4194 Decl *RealDecl = dcl.getAs<Decl>(); 4195 4196 // If there is no declaration, there was an error parsing it. Just ignore it. 4197 if (RealDecl == 0) 4198 return; 4199 4200 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4201 QualType Type = Var->getType(); 4202 4203 // C++0x [dcl.spec.auto]p3 4204 if (TypeContainsUndeducedAuto) { 4205 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4206 << Var->getDeclName() << Type; 4207 Var->setInvalidDecl(); 4208 return; 4209 } 4210 4211 switch (Var->isThisDeclarationADefinition()) { 4212 case VarDecl::Definition: 4213 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4214 break; 4215 4216 // We have an out-of-line definition of a static data member 4217 // that has an in-class initializer, so we type-check this like 4218 // a declaration. 4219 // 4220 // Fall through 4221 4222 case VarDecl::DeclarationOnly: 4223 // It's only a declaration. 4224 4225 // Block scope. C99 6.7p7: If an identifier for an object is 4226 // declared with no linkage (C99 6.2.2p6), the type for the 4227 // object shall be complete. 4228 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4229 !Var->getLinkage() && !Var->isInvalidDecl() && 4230 RequireCompleteType(Var->getLocation(), Type, 4231 diag::err_typecheck_decl_incomplete_type)) 4232 Var->setInvalidDecl(); 4233 4234 // Make sure that the type is not abstract. 4235 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4236 RequireNonAbstractType(Var->getLocation(), Type, 4237 diag::err_abstract_type_in_decl, 4238 AbstractVariableType)) 4239 Var->setInvalidDecl(); 4240 return; 4241 4242 case VarDecl::TentativeDefinition: 4243 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4244 // object that has file scope without an initializer, and without a 4245 // storage-class specifier or with the storage-class specifier "static", 4246 // constitutes a tentative definition. Note: A tentative definition with 4247 // external linkage is valid (C99 6.2.2p5). 4248 if (!Var->isInvalidDecl()) { 4249 if (const IncompleteArrayType *ArrayT 4250 = Context.getAsIncompleteArrayType(Type)) { 4251 if (RequireCompleteType(Var->getLocation(), 4252 ArrayT->getElementType(), 4253 diag::err_illegal_decl_array_incomplete_type)) 4254 Var->setInvalidDecl(); 4255 } else if (Var->getStorageClass() == VarDecl::Static) { 4256 // C99 6.9.2p3: If the declaration of an identifier for an object is 4257 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4258 // declared type shall not be an incomplete type. 4259 // NOTE: code such as the following 4260 // static struct s; 4261 // struct s { int a; }; 4262 // is accepted by gcc. Hence here we issue a warning instead of 4263 // an error and we do not invalidate the static declaration. 4264 // NOTE: to avoid multiple warnings, only check the first declaration. 4265 if (Var->getPreviousDeclaration() == 0) 4266 RequireCompleteType(Var->getLocation(), Type, 4267 diag::ext_typecheck_decl_incomplete_type); 4268 } 4269 } 4270 4271 // Record the tentative definition; we're done. 4272 if (!Var->isInvalidDecl()) 4273 TentativeDefinitions.push_back(Var); 4274 return; 4275 } 4276 4277 // Provide a specific diagnostic for uninitialized variable 4278 // definitions with incomplete array type. 4279 if (Type->isIncompleteArrayType()) { 4280 Diag(Var->getLocation(), 4281 diag::err_typecheck_incomplete_array_needs_initializer); 4282 Var->setInvalidDecl(); 4283 return; 4284 } 4285 4286 // Provide a specific diagnostic for uninitialized variable 4287 // definitions with reference type. 4288 if (Type->isReferenceType()) { 4289 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4290 << Var->getDeclName() 4291 << SourceRange(Var->getLocation(), Var->getLocation()); 4292 Var->setInvalidDecl(); 4293 return; 4294 } 4295 4296 // Do not attempt to type-check the default initializer for a 4297 // variable with dependent type. 4298 if (Type->isDependentType()) 4299 return; 4300 4301 if (Var->isInvalidDecl()) 4302 return; 4303 4304 if (RequireCompleteType(Var->getLocation(), 4305 Context.getBaseElementType(Type), 4306 diag::err_typecheck_decl_incomplete_type)) { 4307 Var->setInvalidDecl(); 4308 return; 4309 } 4310 4311 // The variable can not have an abstract class type. 4312 if (RequireNonAbstractType(Var->getLocation(), Type, 4313 diag::err_abstract_type_in_decl, 4314 AbstractVariableType)) { 4315 Var->setInvalidDecl(); 4316 return; 4317 } 4318 4319 const RecordType *Record 4320 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4321 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4322 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4323 // C++03 [dcl.init]p9: 4324 // If no initializer is specified for an object, and the 4325 // object is of (possibly cv-qualified) non-POD class type (or 4326 // array thereof), the object shall be default-initialized; if 4327 // the object is of const-qualified type, the underlying class 4328 // type shall have a user-declared default 4329 // constructor. Otherwise, if no initializer is specified for 4330 // a non- static object, the object and its subobjects, if 4331 // any, have an indeterminate initial value); if the object 4332 // or any of its subobjects are of const-qualified type, the 4333 // program is ill-formed. 4334 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4335 } else { 4336 // Check for jumps past the implicit initializer. C++0x 4337 // clarifies that this applies to a "variable with automatic 4338 // storage duration", not a "local variable". 4339 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 4340 setFunctionHasBranchProtectedScope(); 4341 4342 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4343 InitializationKind Kind 4344 = InitializationKind::CreateDefault(Var->getLocation()); 4345 4346 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4347 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4348 MultiExprArg(*this, 0, 0)); 4349 if (Init.isInvalid()) 4350 Var->setInvalidDecl(); 4351 else if (Init.get()) { 4352 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4353 4354 if (getLangOptions().CPlusPlus && !Var->isInvalidDecl() && 4355 Var->hasGlobalStorage() && 4356 !Var->getDeclContext()->isDependentContext() && 4357 !Var->getInit()->isConstantInitializer(Context, false)) 4358 Diag(Var->getLocation(), diag::warn_global_constructor); 4359 } 4360 } 4361 4362 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4363 FinalizeVarWithDestructor(Var, Record); 4364 } 4365} 4366 4367Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4368 DeclPtrTy *Group, 4369 unsigned NumDecls) { 4370 llvm::SmallVector<Decl*, 8> Decls; 4371 4372 if (DS.isTypeSpecOwned()) 4373 Decls.push_back((Decl*)DS.getTypeRep()); 4374 4375 for (unsigned i = 0; i != NumDecls; ++i) 4376 if (Decl *D = Group[i].getAs<Decl>()) 4377 Decls.push_back(D); 4378 4379 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4380 Decls.data(), Decls.size())); 4381} 4382 4383 4384/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4385/// to introduce parameters into function prototype scope. 4386Sema::DeclPtrTy 4387Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4388 const DeclSpec &DS = D.getDeclSpec(); 4389 4390 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4391 VarDecl::StorageClass StorageClass = VarDecl::None; 4392 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4393 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4394 StorageClass = VarDecl::Register; 4395 StorageClassAsWritten = VarDecl::Register; 4396 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4397 Diag(DS.getStorageClassSpecLoc(), 4398 diag::err_invalid_storage_class_in_func_decl); 4399 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4400 } 4401 4402 if (D.getDeclSpec().isThreadSpecified()) 4403 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4404 4405 DiagnoseFunctionSpecifiers(D); 4406 4407 // Check that there are no default arguments inside the type of this 4408 // parameter (C++ only). 4409 if (getLangOptions().CPlusPlus) 4410 CheckExtraCXXDefaultArguments(D); 4411 4412 TagDecl *OwnedDecl = 0; 4413 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4414 QualType parmDeclType = TInfo->getType(); 4415 4416 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4417 // C++ [dcl.fct]p6: 4418 // Types shall not be defined in return or parameter types. 4419 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4420 << Context.getTypeDeclType(OwnedDecl); 4421 } 4422 4423 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4424 IdentifierInfo *II = D.getIdentifier(); 4425 if (II) { 4426 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4427 ForRedeclaration); 4428 LookupName(R, S); 4429 if (R.isSingleResult()) { 4430 NamedDecl *PrevDecl = R.getFoundDecl(); 4431 if (PrevDecl->isTemplateParameter()) { 4432 // Maybe we will complain about the shadowed template parameter. 4433 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4434 // Just pretend that we didn't see the previous declaration. 4435 PrevDecl = 0; 4436 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4437 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4438 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4439 4440 // Recover by removing the name 4441 II = 0; 4442 D.SetIdentifier(0, D.getIdentifierLoc()); 4443 D.setInvalidType(true); 4444 } 4445 } 4446 } 4447 4448 // Temporarily put parameter variables in the translation unit, not 4449 // the enclosing context. This prevents them from accidentally 4450 // looking like class members in C++. 4451 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4452 TInfo, parmDeclType, II, 4453 D.getIdentifierLoc(), 4454 StorageClass, StorageClassAsWritten); 4455 4456 if (D.isInvalidType()) 4457 New->setInvalidDecl(); 4458 4459 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4460 if (D.getCXXScopeSpec().isSet()) { 4461 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4462 << D.getCXXScopeSpec().getRange(); 4463 New->setInvalidDecl(); 4464 } 4465 4466 // Add the parameter declaration into this scope. 4467 S->AddDecl(DeclPtrTy::make(New)); 4468 if (II) 4469 IdResolver.AddDecl(New); 4470 4471 ProcessDeclAttributes(S, New, D); 4472 4473 if (New->hasAttr<BlocksAttr>()) { 4474 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4475 } 4476 return DeclPtrTy::make(New); 4477} 4478 4479/// \brief Synthesizes a variable for a parameter arising from a 4480/// typedef. 4481ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4482 SourceLocation Loc, 4483 QualType T) { 4484 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4485 T, Context.getTrivialTypeSourceInfo(T, Loc), 4486 VarDecl::None, VarDecl::None, 0); 4487 Param->setImplicit(); 4488 return Param; 4489} 4490 4491ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4492 TypeSourceInfo *TSInfo, QualType T, 4493 IdentifierInfo *Name, 4494 SourceLocation NameLoc, 4495 VarDecl::StorageClass StorageClass, 4496 VarDecl::StorageClass StorageClassAsWritten) { 4497 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4498 adjustParameterType(T), TSInfo, 4499 StorageClass, StorageClassAsWritten, 4500 0); 4501 4502 // Parameters can not be abstract class types. 4503 // For record types, this is done by the AbstractClassUsageDiagnoser once 4504 // the class has been completely parsed. 4505 if (!CurContext->isRecord() && 4506 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4507 AbstractParamType)) 4508 New->setInvalidDecl(); 4509 4510 // Parameter declarators cannot be interface types. All ObjC objects are 4511 // passed by reference. 4512 if (T->isObjCObjectType()) { 4513 Diag(NameLoc, 4514 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4515 New->setInvalidDecl(); 4516 } 4517 4518 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4519 // duration shall not be qualified by an address-space qualifier." 4520 // Since all parameters have automatic store duration, they can not have 4521 // an address space. 4522 if (T.getAddressSpace() != 0) { 4523 Diag(NameLoc, diag::err_arg_with_address_space); 4524 New->setInvalidDecl(); 4525 } 4526 4527 return New; 4528} 4529 4530void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4531 SourceLocation LocAfterDecls) { 4532 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4533 "Not a function declarator!"); 4534 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4535 4536 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4537 // for a K&R function. 4538 if (!FTI.hasPrototype) { 4539 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4540 --i; 4541 if (FTI.ArgInfo[i].Param == 0) { 4542 llvm::SmallString<256> Code; 4543 llvm::raw_svector_ostream(Code) << " int " 4544 << FTI.ArgInfo[i].Ident->getName() 4545 << ";\n"; 4546 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4547 << FTI.ArgInfo[i].Ident 4548 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4549 4550 // Implicitly declare the argument as type 'int' for lack of a better 4551 // type. 4552 DeclSpec DS; 4553 const char* PrevSpec; // unused 4554 unsigned DiagID; // unused 4555 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4556 PrevSpec, DiagID); 4557 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4558 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4559 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4560 } 4561 } 4562 } 4563} 4564 4565Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4566 Declarator &D) { 4567 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4568 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4569 "Not a function declarator!"); 4570 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4571 4572 if (FTI.hasPrototype) { 4573 // FIXME: Diagnose arguments without names in C. 4574 } 4575 4576 Scope *ParentScope = FnBodyScope->getParent(); 4577 4578 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4579 MultiTemplateParamsArg(*this), 4580 /*IsFunctionDefinition=*/true); 4581 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4582} 4583 4584static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4585 // Don't warn about invalid declarations. 4586 if (FD->isInvalidDecl()) 4587 return false; 4588 4589 // Or declarations that aren't global. 4590 if (!FD->isGlobal()) 4591 return false; 4592 4593 // Don't warn about C++ member functions. 4594 if (isa<CXXMethodDecl>(FD)) 4595 return false; 4596 4597 // Don't warn about 'main'. 4598 if (FD->isMain()) 4599 return false; 4600 4601 // Don't warn about inline functions. 4602 if (FD->isInlineSpecified()) 4603 return false; 4604 4605 // Don't warn about function templates. 4606 if (FD->getDescribedFunctionTemplate()) 4607 return false; 4608 4609 // Don't warn about function template specializations. 4610 if (FD->isFunctionTemplateSpecialization()) 4611 return false; 4612 4613 bool MissingPrototype = true; 4614 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4615 Prev; Prev = Prev->getPreviousDeclaration()) { 4616 // Ignore any declarations that occur in function or method 4617 // scope, because they aren't visible from the header. 4618 if (Prev->getDeclContext()->isFunctionOrMethod()) 4619 continue; 4620 4621 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4622 break; 4623 } 4624 4625 return MissingPrototype; 4626} 4627 4628Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4629 // Clear the last template instantiation error context. 4630 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4631 4632 if (!D) 4633 return D; 4634 FunctionDecl *FD = 0; 4635 4636 if (FunctionTemplateDecl *FunTmpl 4637 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4638 FD = FunTmpl->getTemplatedDecl(); 4639 else 4640 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4641 4642 // Enter a new function scope 4643 PushFunctionScope(); 4644 4645 // See if this is a redefinition. 4646 // But don't complain if we're in GNU89 mode and the previous definition 4647 // was an extern inline function. 4648 const FunctionDecl *Definition; 4649 if (FD->hasBody(Definition) && 4650 !canRedefineFunction(Definition, getLangOptions())) { 4651 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4652 Diag(Definition->getLocation(), diag::note_previous_definition); 4653 } 4654 4655 // Builtin functions cannot be defined. 4656 if (unsigned BuiltinID = FD->getBuiltinID()) { 4657 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4658 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4659 FD->setInvalidDecl(); 4660 } 4661 } 4662 4663 // The return type of a function definition must be complete 4664 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4665 QualType ResultType = FD->getResultType(); 4666 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4667 !FD->isInvalidDecl() && 4668 RequireCompleteType(FD->getLocation(), ResultType, 4669 diag::err_func_def_incomplete_result)) 4670 FD->setInvalidDecl(); 4671 4672 // GNU warning -Wmissing-prototypes: 4673 // Warn if a global function is defined without a previous 4674 // prototype declaration. This warning is issued even if the 4675 // definition itself provides a prototype. The aim is to detect 4676 // global functions that fail to be declared in header files. 4677 if (ShouldWarnAboutMissingPrototype(FD)) 4678 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4679 4680 if (FnBodyScope) 4681 PushDeclContext(FnBodyScope, FD); 4682 4683 // Check the validity of our function parameters 4684 CheckParmsForFunctionDef(FD); 4685 4686 bool ShouldCheckShadow = 4687 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4688 4689 // Introduce our parameters into the function scope 4690 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4691 ParmVarDecl *Param = FD->getParamDecl(p); 4692 Param->setOwningFunction(FD); 4693 4694 // If this has an identifier, add it to the scope stack. 4695 if (Param->getIdentifier() && FnBodyScope) { 4696 if (ShouldCheckShadow) 4697 CheckShadow(FnBodyScope, Param); 4698 4699 PushOnScopeChains(Param, FnBodyScope); 4700 } 4701 } 4702 4703 // Checking attributes of current function definition 4704 // dllimport attribute. 4705 if (FD->getAttr<DLLImportAttr>() && 4706 (!FD->getAttr<DLLExportAttr>())) { 4707 // dllimport attribute cannot be applied to definition. 4708 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4709 Diag(FD->getLocation(), 4710 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4711 << "dllimport"; 4712 FD->setInvalidDecl(); 4713 return DeclPtrTy::make(FD); 4714 } 4715 4716 // Visual C++ appears to not think this is an issue, so only issue 4717 // a warning when Microsoft extensions are disabled. 4718 if (!LangOpts.Microsoft) { 4719 // If a symbol previously declared dllimport is later defined, the 4720 // attribute is ignored in subsequent references, and a warning is 4721 // emitted. 4722 Diag(FD->getLocation(), 4723 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4724 << FD->getNameAsCString() << "dllimport"; 4725 } 4726 } 4727 return DeclPtrTy::make(FD); 4728} 4729 4730/// \brief Given the set of return statements within a function body, 4731/// compute the variables that are subject to the named return value 4732/// optimization. 4733/// 4734/// Each of the variables that is subject to the named return value 4735/// optimization will be marked as NRVO variables in the AST, and any 4736/// return statement that has a marked NRVO variable as its NRVO candidate can 4737/// use the named return value optimization. 4738/// 4739/// This function applies a very simplistic algorithm for NRVO: if every return 4740/// statement in the function has the same NRVO candidate, that candidate is 4741/// the NRVO variable. 4742/// 4743/// FIXME: Employ a smarter algorithm that accounts for multiple return 4744/// statements and the lifetimes of the NRVO candidates. We should be able to 4745/// find a maximal set of NRVO variables. 4746static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4747 const VarDecl *NRVOCandidate = 0; 4748 for (unsigned I = 0; I != NumReturns; ++I) { 4749 if (!Returns[I]->getNRVOCandidate()) 4750 return; 4751 4752 if (!NRVOCandidate) 4753 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4754 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4755 return; 4756 } 4757 4758 if (NRVOCandidate) 4759 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4760} 4761 4762Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4763 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4764} 4765 4766Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4767 bool IsInstantiation) { 4768 Decl *dcl = D.getAs<Decl>(); 4769 Stmt *Body = BodyArg.takeAs<Stmt>(); 4770 4771 FunctionDecl *FD = 0; 4772 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4773 if (FunTmpl) 4774 FD = FunTmpl->getTemplatedDecl(); 4775 else 4776 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4777 4778 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4779 4780 if (FD) { 4781 FD->setBody(Body); 4782 if (FD->isMain()) { 4783 // C and C++ allow for main to automagically return 0. 4784 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4785 FD->setHasImplicitReturnZero(true); 4786 WP.disableCheckFallThrough(); 4787 } 4788 4789 if (!FD->isInvalidDecl()) { 4790 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4791 4792 // If this is a constructor, we need a vtable. 4793 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4794 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4795 4796 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4797 FunctionScopes.back()->Returns.size()); 4798 } 4799 4800 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4801 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4802 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4803 MD->setBody(Body); 4804 MD->setEndLoc(Body->getLocEnd()); 4805 if (!MD->isInvalidDecl()) 4806 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4807 } else { 4808 return DeclPtrTy(); 4809 } 4810 4811 // Verify and clean out per-function state. 4812 4813 // Check goto/label use. 4814 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4815 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4816 LabelStmt *L = I->second; 4817 4818 // Verify that we have no forward references left. If so, there was a goto 4819 // or address of a label taken, but no definition of it. Label fwd 4820 // definitions are indicated with a null substmt. 4821 if (L->getSubStmt() != 0) 4822 continue; 4823 4824 // Emit error. 4825 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4826 4827 // At this point, we have gotos that use the bogus label. Stitch it into 4828 // the function body so that they aren't leaked and that the AST is well 4829 // formed. 4830 if (Body == 0) { 4831 // The whole function wasn't parsed correctly. 4832 continue; 4833 } 4834 4835 // Otherwise, the body is valid: we want to stitch the label decl into the 4836 // function somewhere so that it is properly owned and so that the goto 4837 // has a valid target. Do this by creating a new compound stmt with the 4838 // label in it. 4839 4840 // Give the label a sub-statement. 4841 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4842 4843 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4844 cast<CXXTryStmt>(Body)->getTryBlock() : 4845 cast<CompoundStmt>(Body); 4846 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4847 Compound->body_end()); 4848 Elements.push_back(L); 4849 Compound->setStmts(Context, Elements.data(), Elements.size()); 4850 } 4851 4852 if (Body) { 4853 // C++ constructors that have function-try-blocks can't have return 4854 // statements in the handlers of that block. (C++ [except.handle]p14) 4855 // Verify this. 4856 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4857 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4858 4859 // Verify that that gotos and switch cases don't jump into scopes illegally. 4860 // Verify that that gotos and switch cases don't jump into scopes illegally. 4861 if (FunctionNeedsScopeChecking() && 4862 !dcl->isInvalidDecl() && 4863 !hasAnyErrorsInThisFunction()) 4864 DiagnoseInvalidJumps(Body); 4865 4866 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 4867 if (!Destructor->getParent()->isDependentType()) 4868 CheckDestructor(Destructor); 4869 4870 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4871 Destructor->getParent()); 4872 } 4873 4874 // If any errors have occurred, clear out any temporaries that may have 4875 // been leftover. This ensures that these temporaries won't be picked up for 4876 // deletion in some later function. 4877 if (PP.getDiagnostics().hasErrorOccurred()) 4878 ExprTemporaries.clear(); 4879 else if (!isa<FunctionTemplateDecl>(dcl)) { 4880 // Since the body is valid, issue any analysis-based warnings that are 4881 // enabled. 4882 QualType ResultType; 4883 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4884 ResultType = FD->getResultType(); 4885 } 4886 else { 4887 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4888 ResultType = MD->getResultType(); 4889 } 4890 AnalysisWarnings.IssueWarnings(WP, dcl); 4891 } 4892 4893 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4894 } 4895 4896 if (!IsInstantiation) 4897 PopDeclContext(); 4898 4899 PopFunctionOrBlockScope(); 4900 4901 // If any errors have occurred, clear out any temporaries that may have 4902 // been leftover. This ensures that these temporaries won't be picked up for 4903 // deletion in some later function. 4904 if (getDiagnostics().hasErrorOccurred()) 4905 ExprTemporaries.clear(); 4906 4907 return D; 4908} 4909 4910/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4911/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4912NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4913 IdentifierInfo &II, Scope *S) { 4914 // Before we produce a declaration for an implicitly defined 4915 // function, see whether there was a locally-scoped declaration of 4916 // this name as a function or variable. If so, use that 4917 // (non-visible) declaration, and complain about it. 4918 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4919 = LocallyScopedExternalDecls.find(&II); 4920 if (Pos != LocallyScopedExternalDecls.end()) { 4921 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4922 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4923 return Pos->second; 4924 } 4925 4926 // Extension in C99. Legal in C90, but warn about it. 4927 if (II.getName().startswith("__builtin_")) 4928 Diag(Loc, diag::warn_builtin_unknown) << &II; 4929 else if (getLangOptions().C99) 4930 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4931 else 4932 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4933 4934 // Set a Declarator for the implicit definition: int foo(); 4935 const char *Dummy; 4936 DeclSpec DS; 4937 unsigned DiagID; 4938 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4939 Error = Error; // Silence warning. 4940 assert(!Error && "Error setting up implicit decl!"); 4941 Declarator D(DS, Declarator::BlockContext); 4942 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4943 0, 0, false, SourceLocation(), 4944 false, 0,0,0, Loc, Loc, D), 4945 SourceLocation()); 4946 D.SetIdentifier(&II, Loc); 4947 4948 // Insert this function into translation-unit scope. 4949 4950 DeclContext *PrevDC = CurContext; 4951 CurContext = Context.getTranslationUnitDecl(); 4952 4953 FunctionDecl *FD = 4954 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4955 FD->setImplicit(); 4956 4957 CurContext = PrevDC; 4958 4959 AddKnownFunctionAttributes(FD); 4960 4961 return FD; 4962} 4963 4964/// \brief Adds any function attributes that we know a priori based on 4965/// the declaration of this function. 4966/// 4967/// These attributes can apply both to implicitly-declared builtins 4968/// (like __builtin___printf_chk) or to library-declared functions 4969/// like NSLog or printf. 4970void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4971 if (FD->isInvalidDecl()) 4972 return; 4973 4974 // If this is a built-in function, map its builtin attributes to 4975 // actual attributes. 4976 if (unsigned BuiltinID = FD->getBuiltinID()) { 4977 // Handle printf-formatting attributes. 4978 unsigned FormatIdx; 4979 bool HasVAListArg; 4980 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4981 if (!FD->getAttr<FormatAttr>()) 4982 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4983 HasVAListArg ? 0 : FormatIdx+2)); 4984 } 4985 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 4986 HasVAListArg)) { 4987 if (!FD->getAttr<FormatAttr>()) 4988 FD->addAttr(::new (Context) FormatAttr(Context, "scanf", FormatIdx+1, 4989 HasVAListArg ? 0 : FormatIdx+2)); 4990 } 4991 4992 // Mark const if we don't care about errno and that is the only 4993 // thing preventing the function from being const. This allows 4994 // IRgen to use LLVM intrinsics for such functions. 4995 if (!getLangOptions().MathErrno && 4996 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4997 if (!FD->getAttr<ConstAttr>()) 4998 FD->addAttr(::new (Context) ConstAttr()); 4999 } 5000 5001 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 5002 FD->setType(Context.getNoReturnType(FD->getType())); 5003 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 5004 FD->addAttr(::new (Context) NoThrowAttr()); 5005 if (Context.BuiltinInfo.isConst(BuiltinID)) 5006 FD->addAttr(::new (Context) ConstAttr()); 5007 } 5008 5009 IdentifierInfo *Name = FD->getIdentifier(); 5010 if (!Name) 5011 return; 5012 if ((!getLangOptions().CPlusPlus && 5013 FD->getDeclContext()->isTranslationUnit()) || 5014 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 5015 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 5016 LinkageSpecDecl::lang_c)) { 5017 // Okay: this could be a libc/libm/Objective-C function we know 5018 // about. 5019 } else 5020 return; 5021 5022 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 5023 // FIXME: NSLog and NSLogv should be target specific 5024 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 5025 // FIXME: We known better than our headers. 5026 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 5027 } else 5028 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 5029 Name->isStr("NSLogv") ? 0 : 2)); 5030 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 5031 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 5032 // target-specific builtins, perhaps? 5033 if (!FD->getAttr<FormatAttr>()) 5034 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 5035 Name->isStr("vasprintf") ? 0 : 3)); 5036 } 5037} 5038 5039TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 5040 TypeSourceInfo *TInfo) { 5041 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 5042 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 5043 5044 if (!TInfo) { 5045 assert(D.isInvalidType() && "no declarator info for valid type"); 5046 TInfo = Context.getTrivialTypeSourceInfo(T); 5047 } 5048 5049 // Scope manipulation handled by caller. 5050 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 5051 D.getIdentifierLoc(), 5052 D.getIdentifier(), 5053 TInfo); 5054 5055 if (const TagType *TT = T->getAs<TagType>()) { 5056 TagDecl *TD = TT->getDecl(); 5057 5058 // If the TagDecl that the TypedefDecl points to is an anonymous decl 5059 // keep track of the TypedefDecl. 5060 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 5061 TD->setTypedefForAnonDecl(NewTD); 5062 } 5063 5064 if (D.isInvalidType()) 5065 NewTD->setInvalidDecl(); 5066 return NewTD; 5067} 5068 5069 5070/// \brief Determine whether a tag with a given kind is acceptable 5071/// as a redeclaration of the given tag declaration. 5072/// 5073/// \returns true if the new tag kind is acceptable, false otherwise. 5074bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5075 TagTypeKind NewTag, 5076 SourceLocation NewTagLoc, 5077 const IdentifierInfo &Name) { 5078 // C++ [dcl.type.elab]p3: 5079 // The class-key or enum keyword present in the 5080 // elaborated-type-specifier shall agree in kind with the 5081 // declaration to which the name in the elaborated-type-specifier 5082 // refers. This rule also applies to the form of 5083 // elaborated-type-specifier that declares a class-name or 5084 // friend class since it can be construed as referring to the 5085 // definition of the class. Thus, in any 5086 // elaborated-type-specifier, the enum keyword shall be used to 5087 // refer to an enumeration (7.2), the union class-key shall be 5088 // used to refer to a union (clause 9), and either the class or 5089 // struct class-key shall be used to refer to a class (clause 9) 5090 // declared using the class or struct class-key. 5091 TagTypeKind OldTag = Previous->getTagKind(); 5092 if (OldTag == NewTag) 5093 return true; 5094 5095 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5096 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5097 // Warn about the struct/class tag mismatch. 5098 bool isTemplate = false; 5099 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5100 isTemplate = Record->getDescribedClassTemplate(); 5101 5102 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5103 << (NewTag == TTK_Class) 5104 << isTemplate << &Name 5105 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5106 OldTag == TTK_Class? "class" : "struct"); 5107 Diag(Previous->getLocation(), diag::note_previous_use); 5108 return true; 5109 } 5110 return false; 5111} 5112 5113/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5114/// former case, Name will be non-null. In the later case, Name will be null. 5115/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5116/// reference/declaration/definition of a tag. 5117Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5118 SourceLocation KWLoc, CXXScopeSpec &SS, 5119 IdentifierInfo *Name, SourceLocation NameLoc, 5120 AttributeList *Attr, AccessSpecifier AS, 5121 MultiTemplateParamsArg TemplateParameterLists, 5122 bool &OwnedDecl, bool &IsDependent) { 5123 // If this is not a definition, it must have a name. 5124 assert((Name != 0 || TUK == TUK_Definition) && 5125 "Nameless record must be a definition!"); 5126 5127 OwnedDecl = false; 5128 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5129 5130 // FIXME: Check explicit specializations more carefully. 5131 bool isExplicitSpecialization = false; 5132 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5133 bool Invalid = false; 5134 if (TUK != TUK_Reference) { 5135 if (TemplateParameterList *TemplateParams 5136 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5137 (TemplateParameterList**)TemplateParameterLists.get(), 5138 TemplateParameterLists.size(), 5139 TUK == TUK_Friend, 5140 isExplicitSpecialization, 5141 Invalid)) { 5142 // All but one template parameter lists have been matching. 5143 --NumMatchedTemplateParamLists; 5144 5145 if (TemplateParams->size() > 0) { 5146 // This is a declaration or definition of a class template (which may 5147 // be a member of another template). 5148 if (Invalid) 5149 return DeclPtrTy(); 5150 5151 OwnedDecl = false; 5152 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5153 SS, Name, NameLoc, Attr, 5154 TemplateParams, 5155 AS); 5156 TemplateParameterLists.release(); 5157 return Result.get(); 5158 } else { 5159 // The "template<>" header is extraneous. 5160 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5161 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5162 isExplicitSpecialization = true; 5163 } 5164 } 5165 } 5166 5167 DeclContext *SearchDC = CurContext; 5168 DeclContext *DC = CurContext; 5169 bool isStdBadAlloc = false; 5170 5171 RedeclarationKind Redecl = ForRedeclaration; 5172 if (TUK == TUK_Friend || TUK == TUK_Reference) 5173 Redecl = NotForRedeclaration; 5174 5175 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5176 5177 if (Name && SS.isNotEmpty()) { 5178 // We have a nested-name tag ('struct foo::bar'). 5179 5180 // Check for invalid 'foo::'. 5181 if (SS.isInvalid()) { 5182 Name = 0; 5183 goto CreateNewDecl; 5184 } 5185 5186 // If this is a friend or a reference to a class in a dependent 5187 // context, don't try to make a decl for it. 5188 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5189 DC = computeDeclContext(SS, false); 5190 if (!DC) { 5191 IsDependent = true; 5192 return DeclPtrTy(); 5193 } 5194 } else { 5195 DC = computeDeclContext(SS, true); 5196 if (!DC) { 5197 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5198 << SS.getRange(); 5199 return DeclPtrTy(); 5200 } 5201 } 5202 5203 if (RequireCompleteDeclContext(SS, DC)) 5204 return DeclPtrTy::make((Decl *)0); 5205 5206 SearchDC = DC; 5207 // Look-up name inside 'foo::'. 5208 LookupQualifiedName(Previous, DC); 5209 5210 if (Previous.isAmbiguous()) 5211 return DeclPtrTy(); 5212 5213 if (Previous.empty()) { 5214 // Name lookup did not find anything. However, if the 5215 // nested-name-specifier refers to the current instantiation, 5216 // and that current instantiation has any dependent base 5217 // classes, we might find something at instantiation time: treat 5218 // this as a dependent elaborated-type-specifier. 5219 if (Previous.wasNotFoundInCurrentInstantiation()) { 5220 IsDependent = true; 5221 return DeclPtrTy(); 5222 } 5223 5224 // A tag 'foo::bar' must already exist. 5225 Diag(NameLoc, diag::err_not_tag_in_scope) 5226 << Kind << Name << DC << SS.getRange(); 5227 Name = 0; 5228 Invalid = true; 5229 goto CreateNewDecl; 5230 } 5231 } else if (Name) { 5232 // If this is a named struct, check to see if there was a previous forward 5233 // declaration or definition. 5234 // FIXME: We're looking into outer scopes here, even when we 5235 // shouldn't be. Doing so can result in ambiguities that we 5236 // shouldn't be diagnosing. 5237 LookupName(Previous, S); 5238 5239 // Note: there used to be some attempt at recovery here. 5240 if (Previous.isAmbiguous()) 5241 return DeclPtrTy(); 5242 5243 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5244 // FIXME: This makes sure that we ignore the contexts associated 5245 // with C structs, unions, and enums when looking for a matching 5246 // tag declaration or definition. See the similar lookup tweak 5247 // in Sema::LookupName; is there a better way to deal with this? 5248 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5249 SearchDC = SearchDC->getParent(); 5250 } 5251 } 5252 5253 if (Previous.isSingleResult() && 5254 Previous.getFoundDecl()->isTemplateParameter()) { 5255 // Maybe we will complain about the shadowed template parameter. 5256 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5257 // Just pretend that we didn't see the previous declaration. 5258 Previous.clear(); 5259 } 5260 5261 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5262 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 5263 // This is a declaration of or a reference to "std::bad_alloc". 5264 isStdBadAlloc = true; 5265 5266 if (Previous.empty() && StdBadAlloc) { 5267 // std::bad_alloc has been implicitly declared (but made invisible to 5268 // name lookup). Fill in this implicit declaration as the previous 5269 // declaration, so that the declarations get chained appropriately. 5270 Previous.addDecl(getStdBadAlloc()); 5271 } 5272 } 5273 5274 // If we didn't find a previous declaration, and this is a reference 5275 // (or friend reference), move to the correct scope. In C++, we 5276 // also need to do a redeclaration lookup there, just in case 5277 // there's a shadow friend decl. 5278 if (Name && Previous.empty() && 5279 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5280 if (Invalid) goto CreateNewDecl; 5281 assert(SS.isEmpty()); 5282 5283 if (TUK == TUK_Reference) { 5284 // C++ [basic.scope.pdecl]p5: 5285 // -- for an elaborated-type-specifier of the form 5286 // 5287 // class-key identifier 5288 // 5289 // if the elaborated-type-specifier is used in the 5290 // decl-specifier-seq or parameter-declaration-clause of a 5291 // function defined in namespace scope, the identifier is 5292 // declared as a class-name in the namespace that contains 5293 // the declaration; otherwise, except as a friend 5294 // declaration, the identifier is declared in the smallest 5295 // non-class, non-function-prototype scope that contains the 5296 // declaration. 5297 // 5298 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5299 // C structs and unions. 5300 // 5301 // It is an error in C++ to declare (rather than define) an enum 5302 // type, including via an elaborated type specifier. We'll 5303 // diagnose that later; for now, declare the enum in the same 5304 // scope as we would have picked for any other tag type. 5305 // 5306 // GNU C also supports this behavior as part of its incomplete 5307 // enum types extension, while GNU C++ does not. 5308 // 5309 // Find the context where we'll be declaring the tag. 5310 // FIXME: We would like to maintain the current DeclContext as the 5311 // lexical context, 5312 while (SearchDC->isRecord()) 5313 SearchDC = SearchDC->getParent(); 5314 5315 // Find the scope where we'll be declaring the tag. 5316 while (S->isClassScope() || 5317 (getLangOptions().CPlusPlus && 5318 S->isFunctionPrototypeScope()) || 5319 ((S->getFlags() & Scope::DeclScope) == 0) || 5320 (S->getEntity() && 5321 ((DeclContext *)S->getEntity())->isTransparentContext())) 5322 S = S->getParent(); 5323 } else { 5324 assert(TUK == TUK_Friend); 5325 // C++ [namespace.memdef]p3: 5326 // If a friend declaration in a non-local class first declares a 5327 // class or function, the friend class or function is a member of 5328 // the innermost enclosing namespace. 5329 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5330 } 5331 5332 // In C++, we need to do a redeclaration lookup to properly 5333 // diagnose some problems. 5334 if (getLangOptions().CPlusPlus) { 5335 Previous.setRedeclarationKind(ForRedeclaration); 5336 LookupQualifiedName(Previous, SearchDC); 5337 } 5338 } 5339 5340 if (!Previous.empty()) { 5341 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5342 5343 // It's okay to have a tag decl in the same scope as a typedef 5344 // which hides a tag decl in the same scope. Finding this 5345 // insanity with a redeclaration lookup can only actually happen 5346 // in C++. 5347 // 5348 // This is also okay for elaborated-type-specifiers, which is 5349 // technically forbidden by the current standard but which is 5350 // okay according to the likely resolution of an open issue; 5351 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5352 if (getLangOptions().CPlusPlus) { 5353 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5354 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5355 TagDecl *Tag = TT->getDecl(); 5356 if (Tag->getDeclName() == Name && 5357 Tag->getDeclContext()->getLookupContext() 5358 ->Equals(TD->getDeclContext()->getLookupContext())) { 5359 PrevDecl = Tag; 5360 Previous.clear(); 5361 Previous.addDecl(Tag); 5362 } 5363 } 5364 } 5365 } 5366 5367 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5368 // If this is a use of a previous tag, or if the tag is already declared 5369 // in the same scope (so that the definition/declaration completes or 5370 // rementions the tag), reuse the decl. 5371 if (TUK == TUK_Reference || TUK == TUK_Friend || 5372 isDeclInScope(PrevDecl, SearchDC, S)) { 5373 // Make sure that this wasn't declared as an enum and now used as a 5374 // struct or something similar. 5375 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5376 bool SafeToContinue 5377 = (PrevTagDecl->getTagKind() != TTK_Enum && 5378 Kind != TTK_Enum); 5379 if (SafeToContinue) 5380 Diag(KWLoc, diag::err_use_with_wrong_tag) 5381 << Name 5382 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5383 PrevTagDecl->getKindName()); 5384 else 5385 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5386 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5387 5388 if (SafeToContinue) 5389 Kind = PrevTagDecl->getTagKind(); 5390 else { 5391 // Recover by making this an anonymous redefinition. 5392 Name = 0; 5393 Previous.clear(); 5394 Invalid = true; 5395 } 5396 } 5397 5398 if (!Invalid) { 5399 // If this is a use, just return the declaration we found. 5400 5401 // FIXME: In the future, return a variant or some other clue 5402 // for the consumer of this Decl to know it doesn't own it. 5403 // For our current ASTs this shouldn't be a problem, but will 5404 // need to be changed with DeclGroups. 5405 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5406 TUK == TUK_Friend) 5407 return DeclPtrTy::make(PrevTagDecl); 5408 5409 // Diagnose attempts to redefine a tag. 5410 if (TUK == TUK_Definition) { 5411 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5412 // If we're defining a specialization and the previous definition 5413 // is from an implicit instantiation, don't emit an error 5414 // here; we'll catch this in the general case below. 5415 if (!isExplicitSpecialization || 5416 !isa<CXXRecordDecl>(Def) || 5417 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5418 == TSK_ExplicitSpecialization) { 5419 Diag(NameLoc, diag::err_redefinition) << Name; 5420 Diag(Def->getLocation(), diag::note_previous_definition); 5421 // If this is a redefinition, recover by making this 5422 // struct be anonymous, which will make any later 5423 // references get the previous definition. 5424 Name = 0; 5425 Previous.clear(); 5426 Invalid = true; 5427 } 5428 } else { 5429 // If the type is currently being defined, complain 5430 // about a nested redefinition. 5431 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5432 if (Tag->isBeingDefined()) { 5433 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5434 Diag(PrevTagDecl->getLocation(), 5435 diag::note_previous_definition); 5436 Name = 0; 5437 Previous.clear(); 5438 Invalid = true; 5439 } 5440 } 5441 5442 // Okay, this is definition of a previously declared or referenced 5443 // tag PrevDecl. We're going to create a new Decl for it. 5444 } 5445 } 5446 // If we get here we have (another) forward declaration or we 5447 // have a definition. Just create a new decl. 5448 5449 } else { 5450 // If we get here, this is a definition of a new tag type in a nested 5451 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5452 // new decl/type. We set PrevDecl to NULL so that the entities 5453 // have distinct types. 5454 Previous.clear(); 5455 } 5456 // If we get here, we're going to create a new Decl. If PrevDecl 5457 // is non-NULL, it's a definition of the tag declared by 5458 // PrevDecl. If it's NULL, we have a new definition. 5459 5460 5461 // Otherwise, PrevDecl is not a tag, but was found with tag 5462 // lookup. This is only actually possible in C++, where a few 5463 // things like templates still live in the tag namespace. 5464 } else { 5465 assert(getLangOptions().CPlusPlus); 5466 5467 // Use a better diagnostic if an elaborated-type-specifier 5468 // found the wrong kind of type on the first 5469 // (non-redeclaration) lookup. 5470 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5471 !Previous.isForRedeclaration()) { 5472 unsigned Kind = 0; 5473 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5474 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5475 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5476 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5477 Invalid = true; 5478 5479 // Otherwise, only diagnose if the declaration is in scope. 5480 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5481 // do nothing 5482 5483 // Diagnose implicit declarations introduced by elaborated types. 5484 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5485 unsigned Kind = 0; 5486 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5487 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5488 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5489 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5490 Invalid = true; 5491 5492 // Otherwise it's a declaration. Call out a particularly common 5493 // case here. 5494 } else if (isa<TypedefDecl>(PrevDecl)) { 5495 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5496 << Name 5497 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5498 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5499 Invalid = true; 5500 5501 // Otherwise, diagnose. 5502 } else { 5503 // The tag name clashes with something else in the target scope, 5504 // issue an error and recover by making this tag be anonymous. 5505 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5506 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5507 Name = 0; 5508 Invalid = true; 5509 } 5510 5511 // The existing declaration isn't relevant to us; we're in a 5512 // new scope, so clear out the previous declaration. 5513 Previous.clear(); 5514 } 5515 } 5516 5517CreateNewDecl: 5518 5519 TagDecl *PrevDecl = 0; 5520 if (Previous.isSingleResult()) 5521 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5522 5523 // If there is an identifier, use the location of the identifier as the 5524 // location of the decl, otherwise use the location of the struct/union 5525 // keyword. 5526 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5527 5528 // Otherwise, create a new declaration. If there is a previous 5529 // declaration of the same entity, the two will be linked via 5530 // PrevDecl. 5531 TagDecl *New; 5532 5533 if (Kind == TTK_Enum) { 5534 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5535 // enum X { A, B, C } D; D should chain to X. 5536 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5537 cast_or_null<EnumDecl>(PrevDecl)); 5538 // If this is an undefined enum, warn. 5539 if (TUK != TUK_Definition && !Invalid) { 5540 TagDecl *Def; 5541 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5542 Diag(Loc, diag::ext_forward_ref_enum_def) 5543 << New; 5544 Diag(Def->getLocation(), diag::note_previous_definition); 5545 } else { 5546 Diag(Loc, 5547 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5548 : diag::ext_forward_ref_enum); 5549 } 5550 } 5551 } else { 5552 // struct/union/class 5553 5554 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5555 // struct X { int A; } D; D should chain to X. 5556 if (getLangOptions().CPlusPlus) { 5557 // FIXME: Look for a way to use RecordDecl for simple structs. 5558 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5559 cast_or_null<CXXRecordDecl>(PrevDecl)); 5560 5561 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 5562 StdBadAlloc = cast<CXXRecordDecl>(New); 5563 } else 5564 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5565 cast_or_null<RecordDecl>(PrevDecl)); 5566 } 5567 5568 // Maybe add qualifier info. 5569 if (SS.isNotEmpty()) { 5570 if (SS.isSet()) { 5571 NestedNameSpecifier *NNS 5572 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5573 New->setQualifierInfo(NNS, SS.getRange()); 5574 if (NumMatchedTemplateParamLists > 0) { 5575 New->setTemplateParameterListsInfo(Context, 5576 NumMatchedTemplateParamLists, 5577 (TemplateParameterList**) TemplateParameterLists.release()); 5578 } 5579 } 5580 else 5581 Invalid = true; 5582 } 5583 5584 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5585 // Add alignment attributes if necessary; these attributes are checked when 5586 // the ASTContext lays out the structure. 5587 // 5588 // It is important for implementing the correct semantics that this 5589 // happen here (in act on tag decl). The #pragma pack stack is 5590 // maintained as a result of parser callbacks which can occur at 5591 // many points during the parsing of a struct declaration (because 5592 // the #pragma tokens are effectively skipped over during the 5593 // parsing of the struct). 5594 AddAlignmentAttributesForRecord(RD); 5595 } 5596 5597 // If this is a specialization of a member class (of a class template), 5598 // check the specialization. 5599 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5600 Invalid = true; 5601 5602 if (Invalid) 5603 New->setInvalidDecl(); 5604 5605 if (Attr) 5606 ProcessDeclAttributeList(S, New, Attr); 5607 5608 // If we're declaring or defining a tag in function prototype scope 5609 // in C, note that this type can only be used within the function. 5610 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5611 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5612 5613 // Set the lexical context. If the tag has a C++ scope specifier, the 5614 // lexical context will be different from the semantic context. 5615 New->setLexicalDeclContext(CurContext); 5616 5617 // Mark this as a friend decl if applicable. 5618 if (TUK == TUK_Friend) 5619 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5620 5621 // Set the access specifier. 5622 if (!Invalid && SearchDC->isRecord()) 5623 SetMemberAccessSpecifier(New, PrevDecl, AS); 5624 5625 if (TUK == TUK_Definition) 5626 New->startDefinition(); 5627 5628 // If this has an identifier, add it to the scope stack. 5629 if (TUK == TUK_Friend) { 5630 // We might be replacing an existing declaration in the lookup tables; 5631 // if so, borrow its access specifier. 5632 if (PrevDecl) 5633 New->setAccess(PrevDecl->getAccess()); 5634 5635 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5636 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5637 if (Name) // can be null along some error paths 5638 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5639 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5640 } else if (Name) { 5641 S = getNonFieldDeclScope(S); 5642 PushOnScopeChains(New, S); 5643 } else { 5644 CurContext->addDecl(New); 5645 } 5646 5647 // If this is the C FILE type, notify the AST context. 5648 if (IdentifierInfo *II = New->getIdentifier()) 5649 if (!New->isInvalidDecl() && 5650 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5651 II->isStr("FILE")) 5652 Context.setFILEDecl(New); 5653 5654 OwnedDecl = true; 5655 return DeclPtrTy::make(New); 5656} 5657 5658void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5659 AdjustDeclIfTemplate(TagD); 5660 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5661 5662 // Enter the tag context. 5663 PushDeclContext(S, Tag); 5664} 5665 5666void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5667 SourceLocation LBraceLoc) { 5668 AdjustDeclIfTemplate(TagD); 5669 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5670 5671 FieldCollector->StartClass(); 5672 5673 if (!Record->getIdentifier()) 5674 return; 5675 5676 // C++ [class]p2: 5677 // [...] The class-name is also inserted into the scope of the 5678 // class itself; this is known as the injected-class-name. For 5679 // purposes of access checking, the injected-class-name is treated 5680 // as if it were a public member name. 5681 CXXRecordDecl *InjectedClassName 5682 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5683 CurContext, Record->getLocation(), 5684 Record->getIdentifier(), 5685 Record->getTagKeywordLoc(), 5686 Record); 5687 InjectedClassName->setImplicit(); 5688 InjectedClassName->setAccess(AS_public); 5689 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5690 InjectedClassName->setDescribedClassTemplate(Template); 5691 PushOnScopeChains(InjectedClassName, S); 5692 assert(InjectedClassName->isInjectedClassName() && 5693 "Broken injected-class-name"); 5694} 5695 5696void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5697 SourceLocation RBraceLoc) { 5698 AdjustDeclIfTemplate(TagD); 5699 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5700 Tag->setRBraceLoc(RBraceLoc); 5701 5702 if (isa<CXXRecordDecl>(Tag)) 5703 FieldCollector->FinishClass(); 5704 5705 // Exit this scope of this tag's definition. 5706 PopDeclContext(); 5707 5708 // Notify the consumer that we've defined a tag. 5709 Consumer.HandleTagDeclDefinition(Tag); 5710} 5711 5712void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5713 AdjustDeclIfTemplate(TagD); 5714 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5715 Tag->setInvalidDecl(); 5716 5717 // We're undoing ActOnTagStartDefinition here, not 5718 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5719 // the FieldCollector. 5720 5721 PopDeclContext(); 5722} 5723 5724// Note that FieldName may be null for anonymous bitfields. 5725bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5726 QualType FieldTy, const Expr *BitWidth, 5727 bool *ZeroWidth) { 5728 // Default to true; that shouldn't confuse checks for emptiness 5729 if (ZeroWidth) 5730 *ZeroWidth = true; 5731 5732 // C99 6.7.2.1p4 - verify the field type. 5733 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5734 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5735 // Handle incomplete types with specific error. 5736 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5737 return true; 5738 if (FieldName) 5739 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5740 << FieldName << FieldTy << BitWidth->getSourceRange(); 5741 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5742 << FieldTy << BitWidth->getSourceRange(); 5743 } 5744 5745 // If the bit-width is type- or value-dependent, don't try to check 5746 // it now. 5747 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5748 return false; 5749 5750 llvm::APSInt Value; 5751 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5752 return true; 5753 5754 if (Value != 0 && ZeroWidth) 5755 *ZeroWidth = false; 5756 5757 // Zero-width bitfield is ok for anonymous field. 5758 if (Value == 0 && FieldName) 5759 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5760 5761 if (Value.isSigned() && Value.isNegative()) { 5762 if (FieldName) 5763 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5764 << FieldName << Value.toString(10); 5765 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5766 << Value.toString(10); 5767 } 5768 5769 if (!FieldTy->isDependentType()) { 5770 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5771 if (Value.getZExtValue() > TypeSize) { 5772 if (!getLangOptions().CPlusPlus) { 5773 if (FieldName) 5774 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5775 << FieldName << (unsigned)Value.getZExtValue() 5776 << (unsigned)TypeSize; 5777 5778 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5779 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5780 } 5781 5782 if (FieldName) 5783 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5784 << FieldName << (unsigned)Value.getZExtValue() 5785 << (unsigned)TypeSize; 5786 else 5787 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5788 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5789 } 5790 } 5791 5792 return false; 5793} 5794 5795/// ActOnField - Each field of a struct/union/class is passed into this in order 5796/// to create a FieldDecl object for it. 5797Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5798 SourceLocation DeclStart, 5799 Declarator &D, ExprTy *BitfieldWidth) { 5800 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5801 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5802 AS_public); 5803 return DeclPtrTy::make(Res); 5804} 5805 5806/// HandleField - Analyze a field of a C struct or a C++ data member. 5807/// 5808FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5809 SourceLocation DeclStart, 5810 Declarator &D, Expr *BitWidth, 5811 AccessSpecifier AS) { 5812 IdentifierInfo *II = D.getIdentifier(); 5813 SourceLocation Loc = DeclStart; 5814 if (II) Loc = D.getIdentifierLoc(); 5815 5816 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5817 QualType T = TInfo->getType(); 5818 if (getLangOptions().CPlusPlus) 5819 CheckExtraCXXDefaultArguments(D); 5820 5821 DiagnoseFunctionSpecifiers(D); 5822 5823 if (D.getDeclSpec().isThreadSpecified()) 5824 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5825 5826 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5827 ForRedeclaration); 5828 5829 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5830 // Maybe we will complain about the shadowed template parameter. 5831 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5832 // Just pretend that we didn't see the previous declaration. 5833 PrevDecl = 0; 5834 } 5835 5836 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5837 PrevDecl = 0; 5838 5839 bool Mutable 5840 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5841 SourceLocation TSSL = D.getSourceRange().getBegin(); 5842 FieldDecl *NewFD 5843 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5844 AS, PrevDecl, &D); 5845 5846 if (NewFD->isInvalidDecl()) 5847 Record->setInvalidDecl(); 5848 5849 if (NewFD->isInvalidDecl() && PrevDecl) { 5850 // Don't introduce NewFD into scope; there's already something 5851 // with the same name in the same scope. 5852 } else if (II) { 5853 PushOnScopeChains(NewFD, S); 5854 } else 5855 Record->addDecl(NewFD); 5856 5857 return NewFD; 5858} 5859 5860/// \brief Build a new FieldDecl and check its well-formedness. 5861/// 5862/// This routine builds a new FieldDecl given the fields name, type, 5863/// record, etc. \p PrevDecl should refer to any previous declaration 5864/// with the same name and in the same scope as the field to be 5865/// created. 5866/// 5867/// \returns a new FieldDecl. 5868/// 5869/// \todo The Declarator argument is a hack. It will be removed once 5870FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5871 TypeSourceInfo *TInfo, 5872 RecordDecl *Record, SourceLocation Loc, 5873 bool Mutable, Expr *BitWidth, 5874 SourceLocation TSSL, 5875 AccessSpecifier AS, NamedDecl *PrevDecl, 5876 Declarator *D) { 5877 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5878 bool InvalidDecl = false; 5879 if (D) InvalidDecl = D->isInvalidType(); 5880 5881 // If we receive a broken type, recover by assuming 'int' and 5882 // marking this declaration as invalid. 5883 if (T.isNull()) { 5884 InvalidDecl = true; 5885 T = Context.IntTy; 5886 } 5887 5888 QualType EltTy = Context.getBaseElementType(T); 5889 if (!EltTy->isDependentType() && 5890 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5891 InvalidDecl = true; 5892 5893 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5894 // than a variably modified type. 5895 if (!InvalidDecl && T->isVariablyModifiedType()) { 5896 bool SizeIsNegative; 5897 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5898 SizeIsNegative); 5899 if (!FixedTy.isNull()) { 5900 Diag(Loc, diag::warn_illegal_constant_array_size); 5901 T = FixedTy; 5902 } else { 5903 if (SizeIsNegative) 5904 Diag(Loc, diag::err_typecheck_negative_array_size); 5905 else 5906 Diag(Loc, diag::err_typecheck_field_variable_size); 5907 InvalidDecl = true; 5908 } 5909 } 5910 5911 // Fields can not have abstract class types 5912 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5913 diag::err_abstract_type_in_decl, 5914 AbstractFieldType)) 5915 InvalidDecl = true; 5916 5917 bool ZeroWidth = false; 5918 // If this is declared as a bit-field, check the bit-field. 5919 if (!InvalidDecl && BitWidth && 5920 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5921 InvalidDecl = true; 5922 DeleteExpr(BitWidth); 5923 BitWidth = 0; 5924 ZeroWidth = false; 5925 } 5926 5927 // Check that 'mutable' is consistent with the type of the declaration. 5928 if (!InvalidDecl && Mutable) { 5929 unsigned DiagID = 0; 5930 if (T->isReferenceType()) 5931 DiagID = diag::err_mutable_reference; 5932 else if (T.isConstQualified()) 5933 DiagID = diag::err_mutable_const; 5934 5935 if (DiagID) { 5936 SourceLocation ErrLoc = Loc; 5937 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5938 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5939 Diag(ErrLoc, DiagID); 5940 Mutable = false; 5941 InvalidDecl = true; 5942 } 5943 } 5944 5945 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5946 BitWidth, Mutable); 5947 if (InvalidDecl) 5948 NewFD->setInvalidDecl(); 5949 5950 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5951 Diag(Loc, diag::err_duplicate_member) << II; 5952 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5953 NewFD->setInvalidDecl(); 5954 } 5955 5956 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5957 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5958 5959 if (!T->isPODType()) 5960 CXXRecord->setPOD(false); 5961 if (!ZeroWidth) 5962 CXXRecord->setEmpty(false); 5963 5964 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5965 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5966 if (RDecl->getDefinition()) { 5967 if (!RDecl->hasTrivialConstructor()) 5968 CXXRecord->setHasTrivialConstructor(false); 5969 if (!RDecl->hasTrivialCopyConstructor()) 5970 CXXRecord->setHasTrivialCopyConstructor(false); 5971 if (!RDecl->hasTrivialCopyAssignment()) 5972 CXXRecord->setHasTrivialCopyAssignment(false); 5973 if (!RDecl->hasTrivialDestructor()) 5974 CXXRecord->setHasTrivialDestructor(false); 5975 5976 // C++ 9.5p1: An object of a class with a non-trivial 5977 // constructor, a non-trivial copy constructor, a non-trivial 5978 // destructor, or a non-trivial copy assignment operator 5979 // cannot be a member of a union, nor can an array of such 5980 // objects. 5981 // TODO: C++0x alters this restriction significantly. 5982 if (Record->isUnion()) { 5983 // We check for copy constructors before constructors 5984 // because otherwise we'll never get complaints about 5985 // copy constructors. 5986 5987 CXXSpecialMember member = CXXInvalid; 5988 if (!RDecl->hasTrivialCopyConstructor()) 5989 member = CXXCopyConstructor; 5990 else if (!RDecl->hasTrivialConstructor()) 5991 member = CXXConstructor; 5992 else if (!RDecl->hasTrivialCopyAssignment()) 5993 member = CXXCopyAssignment; 5994 else if (!RDecl->hasTrivialDestructor()) 5995 member = CXXDestructor; 5996 5997 if (member != CXXInvalid) { 5998 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5999 DiagnoseNontrivial(RT, member); 6000 NewFD->setInvalidDecl(); 6001 } 6002 } 6003 } 6004 } 6005 } 6006 6007 // FIXME: We need to pass in the attributes given an AST 6008 // representation, not a parser representation. 6009 if (D) 6010 // FIXME: What to pass instead of TUScope? 6011 ProcessDeclAttributes(TUScope, NewFD, *D); 6012 6013 if (T.isObjCGCWeak()) 6014 Diag(Loc, diag::warn_attribute_weak_on_field); 6015 6016 NewFD->setAccess(AS); 6017 6018 // C++ [dcl.init.aggr]p1: 6019 // An aggregate is an array or a class (clause 9) with [...] no 6020 // private or protected non-static data members (clause 11). 6021 // A POD must be an aggregate. 6022 if (getLangOptions().CPlusPlus && 6023 (AS == AS_private || AS == AS_protected)) { 6024 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 6025 CXXRecord->setAggregate(false); 6026 CXXRecord->setPOD(false); 6027 } 6028 6029 return NewFD; 6030} 6031 6032/// DiagnoseNontrivial - Given that a class has a non-trivial 6033/// special member, figure out why. 6034void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 6035 QualType QT(T, 0U); 6036 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 6037 6038 // Check whether the member was user-declared. 6039 switch (member) { 6040 case CXXInvalid: 6041 break; 6042 6043 case CXXConstructor: 6044 if (RD->hasUserDeclaredConstructor()) { 6045 typedef CXXRecordDecl::ctor_iterator ctor_iter; 6046 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 6047 const FunctionDecl *body = 0; 6048 ci->hasBody(body); 6049 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 6050 SourceLocation CtorLoc = ci->getLocation(); 6051 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6052 return; 6053 } 6054 } 6055 6056 assert(0 && "found no user-declared constructors"); 6057 return; 6058 } 6059 break; 6060 6061 case CXXCopyConstructor: 6062 if (RD->hasUserDeclaredCopyConstructor()) { 6063 SourceLocation CtorLoc = 6064 RD->getCopyConstructor(Context, 0)->getLocation(); 6065 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6066 return; 6067 } 6068 break; 6069 6070 case CXXCopyAssignment: 6071 if (RD->hasUserDeclaredCopyAssignment()) { 6072 // FIXME: this should use the location of the copy 6073 // assignment, not the type. 6074 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6075 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6076 return; 6077 } 6078 break; 6079 6080 case CXXDestructor: 6081 if (RD->hasUserDeclaredDestructor()) { 6082 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6083 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6084 return; 6085 } 6086 break; 6087 } 6088 6089 typedef CXXRecordDecl::base_class_iterator base_iter; 6090 6091 // Virtual bases and members inhibit trivial copying/construction, 6092 // but not trivial destruction. 6093 if (member != CXXDestructor) { 6094 // Check for virtual bases. vbases includes indirect virtual bases, 6095 // so we just iterate through the direct bases. 6096 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6097 if (bi->isVirtual()) { 6098 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6099 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6100 return; 6101 } 6102 6103 // Check for virtual methods. 6104 typedef CXXRecordDecl::method_iterator meth_iter; 6105 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6106 ++mi) { 6107 if (mi->isVirtual()) { 6108 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6109 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6110 return; 6111 } 6112 } 6113 } 6114 6115 bool (CXXRecordDecl::*hasTrivial)() const; 6116 switch (member) { 6117 case CXXConstructor: 6118 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6119 case CXXCopyConstructor: 6120 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6121 case CXXCopyAssignment: 6122 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6123 case CXXDestructor: 6124 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6125 default: 6126 assert(0 && "unexpected special member"); return; 6127 } 6128 6129 // Check for nontrivial bases (and recurse). 6130 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6131 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6132 assert(BaseRT && "Don't know how to handle dependent bases"); 6133 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6134 if (!(BaseRecTy->*hasTrivial)()) { 6135 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6136 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6137 DiagnoseNontrivial(BaseRT, member); 6138 return; 6139 } 6140 } 6141 6142 // Check for nontrivial members (and recurse). 6143 typedef RecordDecl::field_iterator field_iter; 6144 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6145 ++fi) { 6146 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6147 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6148 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6149 6150 if (!(EltRD->*hasTrivial)()) { 6151 SourceLocation FLoc = (*fi)->getLocation(); 6152 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6153 DiagnoseNontrivial(EltRT, member); 6154 return; 6155 } 6156 } 6157 } 6158 6159 assert(0 && "found no explanation for non-trivial member"); 6160} 6161 6162/// TranslateIvarVisibility - Translate visibility from a token ID to an 6163/// AST enum value. 6164static ObjCIvarDecl::AccessControl 6165TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6166 switch (ivarVisibility) { 6167 default: assert(0 && "Unknown visitibility kind"); 6168 case tok::objc_private: return ObjCIvarDecl::Private; 6169 case tok::objc_public: return ObjCIvarDecl::Public; 6170 case tok::objc_protected: return ObjCIvarDecl::Protected; 6171 case tok::objc_package: return ObjCIvarDecl::Package; 6172 } 6173} 6174 6175/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6176/// in order to create an IvarDecl object for it. 6177Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6178 SourceLocation DeclStart, 6179 DeclPtrTy IntfDecl, 6180 Declarator &D, ExprTy *BitfieldWidth, 6181 tok::ObjCKeywordKind Visibility) { 6182 6183 IdentifierInfo *II = D.getIdentifier(); 6184 Expr *BitWidth = (Expr*)BitfieldWidth; 6185 SourceLocation Loc = DeclStart; 6186 if (II) Loc = D.getIdentifierLoc(); 6187 6188 // FIXME: Unnamed fields can be handled in various different ways, for 6189 // example, unnamed unions inject all members into the struct namespace! 6190 6191 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6192 QualType T = TInfo->getType(); 6193 6194 if (BitWidth) { 6195 // 6.7.2.1p3, 6.7.2.1p4 6196 if (VerifyBitField(Loc, II, T, BitWidth)) { 6197 D.setInvalidType(); 6198 DeleteExpr(BitWidth); 6199 BitWidth = 0; 6200 } 6201 } else { 6202 // Not a bitfield. 6203 6204 // validate II. 6205 6206 } 6207 if (T->isReferenceType()) { 6208 Diag(Loc, diag::err_ivar_reference_type); 6209 D.setInvalidType(); 6210 } 6211 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6212 // than a variably modified type. 6213 else if (T->isVariablyModifiedType()) { 6214 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6215 D.setInvalidType(); 6216 } 6217 6218 // Get the visibility (access control) for this ivar. 6219 ObjCIvarDecl::AccessControl ac = 6220 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6221 : ObjCIvarDecl::None; 6222 // Must set ivar's DeclContext to its enclosing interface. 6223 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6224 ObjCContainerDecl *EnclosingContext; 6225 if (ObjCImplementationDecl *IMPDecl = 6226 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6227 // Case of ivar declared in an implementation. Context is that of its class. 6228 EnclosingContext = IMPDecl->getClassInterface(); 6229 assert(EnclosingContext && "Implementation has no class interface!"); 6230 } else { 6231 if (ObjCCategoryDecl *CDecl = 6232 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6233 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6234 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6235 return DeclPtrTy(); 6236 } 6237 } 6238 EnclosingContext = EnclosingDecl; 6239 } 6240 6241 // Construct the decl. 6242 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6243 EnclosingContext, Loc, II, T, 6244 TInfo, ac, (Expr *)BitfieldWidth); 6245 6246 if (II) { 6247 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6248 ForRedeclaration); 6249 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6250 && !isa<TagDecl>(PrevDecl)) { 6251 Diag(Loc, diag::err_duplicate_member) << II; 6252 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6253 NewID->setInvalidDecl(); 6254 } 6255 } 6256 6257 // Process attributes attached to the ivar. 6258 ProcessDeclAttributes(S, NewID, D); 6259 6260 if (D.isInvalidType()) 6261 NewID->setInvalidDecl(); 6262 6263 if (II) { 6264 // FIXME: When interfaces are DeclContexts, we'll need to add 6265 // these to the interface. 6266 S->AddDecl(DeclPtrTy::make(NewID)); 6267 IdResolver.AddDecl(NewID); 6268 } 6269 6270 return DeclPtrTy::make(NewID); 6271} 6272 6273void Sema::ActOnFields(Scope* S, 6274 SourceLocation RecLoc, DeclPtrTy RecDecl, 6275 DeclPtrTy *Fields, unsigned NumFields, 6276 SourceLocation LBrac, SourceLocation RBrac, 6277 AttributeList *Attr) { 6278 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6279 assert(EnclosingDecl && "missing record or interface decl"); 6280 6281 // If the decl this is being inserted into is invalid, then it may be a 6282 // redeclaration or some other bogus case. Don't try to add fields to it. 6283 if (EnclosingDecl->isInvalidDecl()) { 6284 // FIXME: Deallocate fields? 6285 return; 6286 } 6287 6288 6289 // Verify that all the fields are okay. 6290 unsigned NumNamedMembers = 0; 6291 llvm::SmallVector<FieldDecl*, 32> RecFields; 6292 6293 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6294 for (unsigned i = 0; i != NumFields; ++i) { 6295 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6296 6297 // Get the type for the field. 6298 Type *FDTy = FD->getType().getTypePtr(); 6299 6300 if (!FD->isAnonymousStructOrUnion()) { 6301 // Remember all fields written by the user. 6302 RecFields.push_back(FD); 6303 } 6304 6305 // If the field is already invalid for some reason, don't emit more 6306 // diagnostics about it. 6307 if (FD->isInvalidDecl()) { 6308 EnclosingDecl->setInvalidDecl(); 6309 continue; 6310 } 6311 6312 // C99 6.7.2.1p2: 6313 // A structure or union shall not contain a member with 6314 // incomplete or function type (hence, a structure shall not 6315 // contain an instance of itself, but may contain a pointer to 6316 // an instance of itself), except that the last member of a 6317 // structure with more than one named member may have incomplete 6318 // array type; such a structure (and any union containing, 6319 // possibly recursively, a member that is such a structure) 6320 // shall not be a member of a structure or an element of an 6321 // array. 6322 if (FDTy->isFunctionType()) { 6323 // Field declared as a function. 6324 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6325 << FD->getDeclName(); 6326 FD->setInvalidDecl(); 6327 EnclosingDecl->setInvalidDecl(); 6328 continue; 6329 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6330 Record && Record->isStruct()) { 6331 // Flexible array member. 6332 if (NumNamedMembers < 1) { 6333 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6334 << FD->getDeclName(); 6335 FD->setInvalidDecl(); 6336 EnclosingDecl->setInvalidDecl(); 6337 continue; 6338 } 6339 if (!FD->getType()->isDependentType() && 6340 !Context.getBaseElementType(FD->getType())->isPODType()) { 6341 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6342 << FD->getDeclName() << FD->getType(); 6343 FD->setInvalidDecl(); 6344 EnclosingDecl->setInvalidDecl(); 6345 continue; 6346 } 6347 6348 // Okay, we have a legal flexible array member at the end of the struct. 6349 if (Record) 6350 Record->setHasFlexibleArrayMember(true); 6351 } else if (!FDTy->isDependentType() && 6352 RequireCompleteType(FD->getLocation(), FD->getType(), 6353 diag::err_field_incomplete)) { 6354 // Incomplete type 6355 FD->setInvalidDecl(); 6356 EnclosingDecl->setInvalidDecl(); 6357 continue; 6358 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6359 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6360 // If this is a member of a union, then entire union becomes "flexible". 6361 if (Record && Record->isUnion()) { 6362 Record->setHasFlexibleArrayMember(true); 6363 } else { 6364 // If this is a struct/class and this is not the last element, reject 6365 // it. Note that GCC supports variable sized arrays in the middle of 6366 // structures. 6367 if (i != NumFields-1) 6368 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6369 << FD->getDeclName() << FD->getType(); 6370 else { 6371 // We support flexible arrays at the end of structs in 6372 // other structs as an extension. 6373 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6374 << FD->getDeclName(); 6375 if (Record) 6376 Record->setHasFlexibleArrayMember(true); 6377 } 6378 } 6379 } 6380 if (Record && FDTTy->getDecl()->hasObjectMember()) 6381 Record->setHasObjectMember(true); 6382 } else if (FDTy->isObjCObjectType()) { 6383 /// A field cannot be an Objective-c object 6384 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6385 FD->setInvalidDecl(); 6386 EnclosingDecl->setInvalidDecl(); 6387 continue; 6388 } else if (getLangOptions().ObjC1 && 6389 getLangOptions().getGCMode() != LangOptions::NonGC && 6390 Record && 6391 (FD->getType()->isObjCObjectPointerType() || 6392 FD->getType().isObjCGCStrong())) 6393 Record->setHasObjectMember(true); 6394 else if (Context.getAsArrayType(FD->getType())) { 6395 QualType BaseType = Context.getBaseElementType(FD->getType()); 6396 if (Record && BaseType->isRecordType() && 6397 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6398 Record->setHasObjectMember(true); 6399 } 6400 // Keep track of the number of named members. 6401 if (FD->getIdentifier()) 6402 ++NumNamedMembers; 6403 } 6404 6405 // Okay, we successfully defined 'Record'. 6406 if (Record) { 6407 Record->completeDefinition(); 6408 } else { 6409 ObjCIvarDecl **ClsFields = 6410 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6411 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6412 ID->setLocEnd(RBrac); 6413 // Add ivar's to class's DeclContext. 6414 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6415 ClsFields[i]->setLexicalDeclContext(ID); 6416 ID->addDecl(ClsFields[i]); 6417 } 6418 // Must enforce the rule that ivars in the base classes may not be 6419 // duplicates. 6420 if (ID->getSuperClass()) 6421 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6422 } else if (ObjCImplementationDecl *IMPDecl = 6423 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6424 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6425 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6426 // Ivar declared in @implementation never belongs to the implementation. 6427 // Only it is in implementation's lexical context. 6428 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6429 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6430 } else if (ObjCCategoryDecl *CDecl = 6431 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6432 // case of ivars in class extension; all other cases have been 6433 // reported as errors elsewhere. 6434 // FIXME. Class extension does not have a LocEnd field. 6435 // CDecl->setLocEnd(RBrac); 6436 // Add ivar's to class extension's DeclContext. 6437 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6438 ClsFields[i]->setLexicalDeclContext(CDecl); 6439 CDecl->addDecl(ClsFields[i]); 6440 } 6441 } 6442 } 6443 6444 if (Attr) 6445 ProcessDeclAttributeList(S, Record, Attr); 6446 6447 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 6448 // set the visibility of this record. 6449 if (Record && !Record->getDeclContext()->isRecord()) 6450 AddPushedVisibilityAttribute(Record); 6451} 6452 6453/// \brief Determine whether the given integral value is representable within 6454/// the given type T. 6455static bool isRepresentableIntegerValue(ASTContext &Context, 6456 llvm::APSInt &Value, 6457 QualType T) { 6458 assert(T->isIntegralType(Context) && "Integral type required!"); 6459 unsigned BitWidth = Context.getIntWidth(T); 6460 6461 if (Value.isUnsigned() || Value.isNonNegative()) 6462 return Value.getActiveBits() < BitWidth; 6463 6464 return Value.getMinSignedBits() <= BitWidth; 6465} 6466 6467// \brief Given an integral type, return the next larger integral type 6468// (or a NULL type of no such type exists). 6469static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6470 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6471 // enum checking below. 6472 assert(T->isIntegralType(Context) && "Integral type required!"); 6473 const unsigned NumTypes = 4; 6474 QualType SignedIntegralTypes[NumTypes] = { 6475 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6476 }; 6477 QualType UnsignedIntegralTypes[NumTypes] = { 6478 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6479 Context.UnsignedLongLongTy 6480 }; 6481 6482 unsigned BitWidth = Context.getTypeSize(T); 6483 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6484 : UnsignedIntegralTypes; 6485 for (unsigned I = 0; I != NumTypes; ++I) 6486 if (Context.getTypeSize(Types[I]) > BitWidth) 6487 return Types[I]; 6488 6489 return QualType(); 6490} 6491 6492EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6493 EnumConstantDecl *LastEnumConst, 6494 SourceLocation IdLoc, 6495 IdentifierInfo *Id, 6496 ExprArg val) { 6497 Expr *Val = (Expr *)val.get(); 6498 6499 unsigned IntWidth = Context.Target.getIntWidth(); 6500 llvm::APSInt EnumVal(IntWidth); 6501 QualType EltTy; 6502 if (Val) { 6503 if (Enum->isDependentType() || Val->isTypeDependent()) 6504 EltTy = Context.DependentTy; 6505 else { 6506 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6507 SourceLocation ExpLoc; 6508 if (!Val->isValueDependent() && 6509 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6510 Val = 0; 6511 } else { 6512 if (!getLangOptions().CPlusPlus) { 6513 // C99 6.7.2.2p2: 6514 // The expression that defines the value of an enumeration constant 6515 // shall be an integer constant expression that has a value 6516 // representable as an int. 6517 6518 // Complain if the value is not representable in an int. 6519 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6520 Diag(IdLoc, diag::ext_enum_value_not_int) 6521 << EnumVal.toString(10) << Val->getSourceRange() 6522 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6523 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6524 // Force the type of the expression to 'int'. 6525 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6526 6527 if (Val != val.get()) { 6528 val.release(); 6529 val = Val; 6530 } 6531 } 6532 } 6533 6534 // C++0x [dcl.enum]p5: 6535 // If the underlying type is not fixed, the type of each enumerator 6536 // is the type of its initializing value: 6537 // - If an initializer is specified for an enumerator, the 6538 // initializing value has the same type as the expression. 6539 EltTy = Val->getType(); 6540 } 6541 } 6542 } 6543 6544 if (!Val) { 6545 if (Enum->isDependentType()) 6546 EltTy = Context.DependentTy; 6547 else if (!LastEnumConst) { 6548 // C++0x [dcl.enum]p5: 6549 // If the underlying type is not fixed, the type of each enumerator 6550 // is the type of its initializing value: 6551 // - If no initializer is specified for the first enumerator, the 6552 // initializing value has an unspecified integral type. 6553 // 6554 // GCC uses 'int' for its unspecified integral type, as does 6555 // C99 6.7.2.2p3. 6556 EltTy = Context.IntTy; 6557 } else { 6558 // Assign the last value + 1. 6559 EnumVal = LastEnumConst->getInitVal(); 6560 ++EnumVal; 6561 EltTy = LastEnumConst->getType(); 6562 6563 // Check for overflow on increment. 6564 if (EnumVal < LastEnumConst->getInitVal()) { 6565 // C++0x [dcl.enum]p5: 6566 // If the underlying type is not fixed, the type of each enumerator 6567 // is the type of its initializing value: 6568 // 6569 // - Otherwise the type of the initializing value is the same as 6570 // the type of the initializing value of the preceding enumerator 6571 // unless the incremented value is not representable in that type, 6572 // in which case the type is an unspecified integral type 6573 // sufficient to contain the incremented value. If no such type 6574 // exists, the program is ill-formed. 6575 QualType T = getNextLargerIntegralType(Context, EltTy); 6576 if (T.isNull()) { 6577 // There is no integral type larger enough to represent this 6578 // value. Complain, then allow the value to wrap around. 6579 EnumVal = LastEnumConst->getInitVal(); 6580 EnumVal.zext(EnumVal.getBitWidth() * 2); 6581 Diag(IdLoc, diag::warn_enumerator_too_large) 6582 << EnumVal.toString(10); 6583 } else { 6584 EltTy = T; 6585 } 6586 6587 // Retrieve the last enumerator's value, extent that type to the 6588 // type that is supposed to be large enough to represent the incremented 6589 // value, then increment. 6590 EnumVal = LastEnumConst->getInitVal(); 6591 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6592 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6593 ++EnumVal; 6594 6595 // If we're not in C++, diagnose the overflow of enumerator values, 6596 // which in C99 means that the enumerator value is not representable in 6597 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6598 // permits enumerator values that are representable in some larger 6599 // integral type. 6600 if (!getLangOptions().CPlusPlus && !T.isNull()) 6601 Diag(IdLoc, diag::warn_enum_value_overflow); 6602 } else if (!getLangOptions().CPlusPlus && 6603 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6604 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6605 Diag(IdLoc, diag::ext_enum_value_not_int) 6606 << EnumVal.toString(10) << 1; 6607 } 6608 } 6609 } 6610 6611 if (!EltTy->isDependentType()) { 6612 // Make the enumerator value match the signedness and size of the 6613 // enumerator's type. 6614 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6615 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6616 } 6617 6618 val.release(); 6619 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6620 Val, EnumVal); 6621} 6622 6623 6624Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6625 DeclPtrTy lastEnumConst, 6626 SourceLocation IdLoc, 6627 IdentifierInfo *Id, 6628 SourceLocation EqualLoc, ExprTy *val) { 6629 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6630 EnumConstantDecl *LastEnumConst = 6631 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6632 Expr *Val = static_cast<Expr*>(val); 6633 6634 // The scope passed in may not be a decl scope. Zip up the scope tree until 6635 // we find one that is. 6636 S = getNonFieldDeclScope(S); 6637 6638 // Verify that there isn't already something declared with this name in this 6639 // scope. 6640 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6641 ForRedeclaration); 6642 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6643 // Maybe we will complain about the shadowed template parameter. 6644 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6645 // Just pretend that we didn't see the previous declaration. 6646 PrevDecl = 0; 6647 } 6648 6649 if (PrevDecl) { 6650 // When in C++, we may get a TagDecl with the same name; in this case the 6651 // enum constant will 'hide' the tag. 6652 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6653 "Received TagDecl when not in C++!"); 6654 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6655 if (isa<EnumConstantDecl>(PrevDecl)) 6656 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6657 else 6658 Diag(IdLoc, diag::err_redefinition) << Id; 6659 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6660 return DeclPtrTy(); 6661 } 6662 } 6663 6664 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6665 IdLoc, Id, Owned(Val)); 6666 6667 // Register this decl in the current scope stack. 6668 if (New) { 6669 New->setAccess(TheEnumDecl->getAccess()); 6670 PushOnScopeChains(New, S); 6671 } 6672 6673 return DeclPtrTy::make(New); 6674} 6675 6676void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6677 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6678 DeclPtrTy *Elements, unsigned NumElements, 6679 Scope *S, AttributeList *Attr) { 6680 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6681 QualType EnumType = Context.getTypeDeclType(Enum); 6682 6683 if (Attr) 6684 ProcessDeclAttributeList(S, Enum, Attr); 6685 6686 if (Enum->isDependentType()) { 6687 for (unsigned i = 0; i != NumElements; ++i) { 6688 EnumConstantDecl *ECD = 6689 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6690 if (!ECD) continue; 6691 6692 ECD->setType(EnumType); 6693 } 6694 6695 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6696 return; 6697 } 6698 6699 // TODO: If the result value doesn't fit in an int, it must be a long or long 6700 // long value. ISO C does not support this, but GCC does as an extension, 6701 // emit a warning. 6702 unsigned IntWidth = Context.Target.getIntWidth(); 6703 unsigned CharWidth = Context.Target.getCharWidth(); 6704 unsigned ShortWidth = Context.Target.getShortWidth(); 6705 6706 // Verify that all the values are okay, compute the size of the values, and 6707 // reverse the list. 6708 unsigned NumNegativeBits = 0; 6709 unsigned NumPositiveBits = 0; 6710 6711 // Keep track of whether all elements have type int. 6712 bool AllElementsInt = true; 6713 6714 for (unsigned i = 0; i != NumElements; ++i) { 6715 EnumConstantDecl *ECD = 6716 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6717 if (!ECD) continue; // Already issued a diagnostic. 6718 6719 const llvm::APSInt &InitVal = ECD->getInitVal(); 6720 6721 // Keep track of the size of positive and negative values. 6722 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6723 NumPositiveBits = std::max(NumPositiveBits, 6724 (unsigned)InitVal.getActiveBits()); 6725 else 6726 NumNegativeBits = std::max(NumNegativeBits, 6727 (unsigned)InitVal.getMinSignedBits()); 6728 6729 // Keep track of whether every enum element has type int (very commmon). 6730 if (AllElementsInt) 6731 AllElementsInt = ECD->getType() == Context.IntTy; 6732 } 6733 6734 // Figure out the type that should be used for this enum. 6735 // FIXME: Support -fshort-enums. 6736 QualType BestType; 6737 unsigned BestWidth; 6738 6739 // C++0x N3000 [conv.prom]p3: 6740 // An rvalue of an unscoped enumeration type whose underlying 6741 // type is not fixed can be converted to an rvalue of the first 6742 // of the following types that can represent all the values of 6743 // the enumeration: int, unsigned int, long int, unsigned long 6744 // int, long long int, or unsigned long long int. 6745 // C99 6.4.4.3p2: 6746 // An identifier declared as an enumeration constant has type int. 6747 // The C99 rule is modified by a gcc extension 6748 QualType BestPromotionType; 6749 6750 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6751 6752 if (NumNegativeBits) { 6753 // If there is a negative value, figure out the smallest integer type (of 6754 // int/long/longlong) that fits. 6755 // If it's packed, check also if it fits a char or a short. 6756 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6757 BestType = Context.SignedCharTy; 6758 BestWidth = CharWidth; 6759 } else if (Packed && NumNegativeBits <= ShortWidth && 6760 NumPositiveBits < ShortWidth) { 6761 BestType = Context.ShortTy; 6762 BestWidth = ShortWidth; 6763 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6764 BestType = Context.IntTy; 6765 BestWidth = IntWidth; 6766 } else { 6767 BestWidth = Context.Target.getLongWidth(); 6768 6769 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6770 BestType = Context.LongTy; 6771 } else { 6772 BestWidth = Context.Target.getLongLongWidth(); 6773 6774 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6775 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6776 BestType = Context.LongLongTy; 6777 } 6778 } 6779 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6780 } else { 6781 // If there is no negative value, figure out the smallest type that fits 6782 // all of the enumerator values. 6783 // If it's packed, check also if it fits a char or a short. 6784 if (Packed && NumPositiveBits <= CharWidth) { 6785 BestType = Context.UnsignedCharTy; 6786 BestPromotionType = Context.IntTy; 6787 BestWidth = CharWidth; 6788 } else if (Packed && NumPositiveBits <= ShortWidth) { 6789 BestType = Context.UnsignedShortTy; 6790 BestPromotionType = Context.IntTy; 6791 BestWidth = ShortWidth; 6792 } else if (NumPositiveBits <= IntWidth) { 6793 BestType = Context.UnsignedIntTy; 6794 BestWidth = IntWidth; 6795 BestPromotionType 6796 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6797 ? Context.UnsignedIntTy : Context.IntTy; 6798 } else if (NumPositiveBits <= 6799 (BestWidth = Context.Target.getLongWidth())) { 6800 BestType = Context.UnsignedLongTy; 6801 BestPromotionType 6802 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6803 ? Context.UnsignedLongTy : Context.LongTy; 6804 } else { 6805 BestWidth = Context.Target.getLongLongWidth(); 6806 assert(NumPositiveBits <= BestWidth && 6807 "How could an initializer get larger than ULL?"); 6808 BestType = Context.UnsignedLongLongTy; 6809 BestPromotionType 6810 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6811 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6812 } 6813 } 6814 6815 // Loop over all of the enumerator constants, changing their types to match 6816 // the type of the enum if needed. 6817 for (unsigned i = 0; i != NumElements; ++i) { 6818 EnumConstantDecl *ECD = 6819 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6820 if (!ECD) continue; // Already issued a diagnostic. 6821 6822 // Standard C says the enumerators have int type, but we allow, as an 6823 // extension, the enumerators to be larger than int size. If each 6824 // enumerator value fits in an int, type it as an int, otherwise type it the 6825 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6826 // that X has type 'int', not 'unsigned'. 6827 6828 // Determine whether the value fits into an int. 6829 llvm::APSInt InitVal = ECD->getInitVal(); 6830 6831 // If it fits into an integer type, force it. Otherwise force it to match 6832 // the enum decl type. 6833 QualType NewTy; 6834 unsigned NewWidth; 6835 bool NewSign; 6836 if (!getLangOptions().CPlusPlus && 6837 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6838 NewTy = Context.IntTy; 6839 NewWidth = IntWidth; 6840 NewSign = true; 6841 } else if (ECD->getType() == BestType) { 6842 // Already the right type! 6843 if (getLangOptions().CPlusPlus) 6844 // C++ [dcl.enum]p4: Following the closing brace of an 6845 // enum-specifier, each enumerator has the type of its 6846 // enumeration. 6847 ECD->setType(EnumType); 6848 continue; 6849 } else { 6850 NewTy = BestType; 6851 NewWidth = BestWidth; 6852 NewSign = BestType->isSignedIntegerType(); 6853 } 6854 6855 // Adjust the APSInt value. 6856 InitVal.extOrTrunc(NewWidth); 6857 InitVal.setIsSigned(NewSign); 6858 ECD->setInitVal(InitVal); 6859 6860 // Adjust the Expr initializer and type. 6861 if (ECD->getInitExpr()) 6862 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 6863 CastExpr::CK_IntegralCast, 6864 ECD->getInitExpr(), 6865 /*base paths*/ 0, 6866 ImplicitCastExpr::RValue)); 6867 if (getLangOptions().CPlusPlus) 6868 // C++ [dcl.enum]p4: Following the closing brace of an 6869 // enum-specifier, each enumerator has the type of its 6870 // enumeration. 6871 ECD->setType(EnumType); 6872 else 6873 ECD->setType(NewTy); 6874 } 6875 6876 Enum->completeDefinition(BestType, BestPromotionType, 6877 NumPositiveBits, NumNegativeBits); 6878} 6879 6880Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6881 ExprArg expr) { 6882 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6883 6884 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6885 Loc, AsmString); 6886 CurContext->addDecl(New); 6887 return DeclPtrTy::make(New); 6888} 6889 6890void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6891 SourceLocation PragmaLoc, 6892 SourceLocation NameLoc) { 6893 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6894 6895 if (PrevDecl) { 6896 PrevDecl->addAttr(::new (Context) WeakAttr()); 6897 } else { 6898 (void)WeakUndeclaredIdentifiers.insert( 6899 std::pair<IdentifierInfo*,WeakInfo> 6900 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6901 } 6902} 6903 6904void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6905 IdentifierInfo* AliasName, 6906 SourceLocation PragmaLoc, 6907 SourceLocation NameLoc, 6908 SourceLocation AliasNameLoc) { 6909 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6910 LookupOrdinaryName); 6911 WeakInfo W = WeakInfo(Name, NameLoc); 6912 6913 if (PrevDecl) { 6914 if (!PrevDecl->hasAttr<AliasAttr>()) 6915 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6916 DeclApplyPragmaWeak(TUScope, ND, W); 6917 } else { 6918 (void)WeakUndeclaredIdentifiers.insert( 6919 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6920 } 6921} 6922