SemaDecl.cpp revision 42c39f39184c5ce9d7f489e5dcb7eec770728a9a
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/TargetInfo.h" 27#include "clang/Basic/SourceManager.h" 28// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 29#include "clang/Lex/Preprocessor.h" 30#include "clang/Lex/HeaderSearch.h" 31#include "llvm/ADT/BitVector.h" 32#include "llvm/ADT/STLExtras.h" 33#include <algorithm> 34#include <functional> 35#include <queue> 36using namespace clang; 37 38/// getDeclName - Return a pretty name for the specified decl if possible, or 39/// an empty string if not. This is used for pretty crash reporting. 40std::string Sema::getDeclName(DeclPtrTy d) { 41 Decl *D = d.getAs<Decl>(); 42 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 43 return DN->getQualifiedNameAsString(); 44 return ""; 45} 46 47Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 48 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 49} 50 51/// \brief If the identifier refers to a type name within this scope, 52/// return the declaration of that type. 53/// 54/// This routine performs ordinary name lookup of the identifier II 55/// within the given scope, with optional C++ scope specifier SS, to 56/// determine whether the name refers to a type. If so, returns an 57/// opaque pointer (actually a QualType) corresponding to that 58/// type. Otherwise, returns NULL. 59/// 60/// If name lookup results in an ambiguity, this routine will complain 61/// and then return NULL. 62Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 63 Scope *S, const CXXScopeSpec *SS, 64 bool isClassName) { 65 // C++ [temp.res]p3: 66 // A qualified-id that refers to a type and in which the 67 // nested-name-specifier depends on a template-parameter (14.6.2) 68 // shall be prefixed by the keyword typename to indicate that the 69 // qualified-id denotes a type, forming an 70 // elaborated-type-specifier (7.1.5.3). 71 // 72 // We therefore do not perform any name lookup if the result would 73 // refer to a member of an unknown specialization. 74 if (SS && isUnknownSpecialization(*SS)) { 75 if (!isClassName) 76 return 0; 77 78 // We know from the grammar that this name refers to a type, so build a 79 // TypenameType node to describe the type. 80 // FIXME: Record somewhere that this TypenameType node has no "typename" 81 // keyword associated with it. 82 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 83 II, SS->getRange()).getAsOpaquePtr(); 84 } 85 86 LookupResult Result 87 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 88 89 NamedDecl *IIDecl = 0; 90 switch (Result.getKind()) { 91 case LookupResult::NotFound: 92 case LookupResult::FoundOverloaded: 93 return 0; 94 95 case LookupResult::AmbiguousBaseSubobjectTypes: 96 case LookupResult::AmbiguousBaseSubobjects: 97 case LookupResult::AmbiguousReference: { 98 // Look to see if we have a type anywhere in the list of results. 99 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 100 Res != ResEnd; ++Res) { 101 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 102 if (!IIDecl || 103 (*Res)->getLocation().getRawEncoding() < 104 IIDecl->getLocation().getRawEncoding()) 105 IIDecl = *Res; 106 } 107 } 108 109 if (!IIDecl) { 110 // None of the entities we found is a type, so there is no way 111 // to even assume that the result is a type. In this case, don't 112 // complain about the ambiguity. The parser will either try to 113 // perform this lookup again (e.g., as an object name), which 114 // will produce the ambiguity, or will complain that it expected 115 // a type name. 116 Result.Destroy(); 117 return 0; 118 } 119 120 // We found a type within the ambiguous lookup; diagnose the 121 // ambiguity and then return that type. This might be the right 122 // answer, or it might not be, but it suppresses any attempt to 123 // perform the name lookup again. 124 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 125 break; 126 } 127 128 case LookupResult::Found: 129 IIDecl = Result.getAsDecl(); 130 break; 131 } 132 133 if (IIDecl) { 134 QualType T; 135 136 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 137 // Check whether we can use this type 138 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 139 140 if (getLangOptions().CPlusPlus) { 141 // C++ [temp.local]p2: 142 // Within the scope of a class template specialization or 143 // partial specialization, when the injected-class-name is 144 // not followed by a <, it is equivalent to the 145 // injected-class-name followed by the template-argument s 146 // of the class template specialization or partial 147 // specialization enclosed in <>. 148 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 149 if (RD->isInjectedClassName()) 150 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 151 T = Template->getInjectedClassNameType(Context); 152 } 153 154 if (T.isNull()) 155 T = Context.getTypeDeclType(TD); 156 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 157 // Check whether we can use this interface. 158 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 159 160 T = Context.getObjCInterfaceType(IDecl); 161 } else 162 return 0; 163 164 if (SS) 165 T = getQualifiedNameType(*SS, T); 166 167 return T.getAsOpaquePtr(); 168 } 169 170 return 0; 171} 172 173/// isTagName() - This method is called *for error recovery purposes only* 174/// to determine if the specified name is a valid tag name ("struct foo"). If 175/// so, this returns the TST for the tag corresponding to it (TST_enum, 176/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 177/// where the user forgot to specify the tag. 178DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 179 // Do a tag name lookup in this scope. 180 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 181 if (R.getKind() == LookupResult::Found) 182 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 183 switch (TD->getTagKind()) { 184 case TagDecl::TK_struct: return DeclSpec::TST_struct; 185 case TagDecl::TK_union: return DeclSpec::TST_union; 186 case TagDecl::TK_class: return DeclSpec::TST_class; 187 case TagDecl::TK_enum: return DeclSpec::TST_enum; 188 } 189 } 190 191 return DeclSpec::TST_unspecified; 192} 193 194 195// Determines the context to return to after temporarily entering a 196// context. This depends in an unnecessarily complicated way on the 197// exact ordering of callbacks from the parser. 198DeclContext *Sema::getContainingDC(DeclContext *DC) { 199 200 // Functions defined inline within classes aren't parsed until we've 201 // finished parsing the top-level class, so the top-level class is 202 // the context we'll need to return to. 203 if (isa<FunctionDecl>(DC)) { 204 DC = DC->getLexicalParent(); 205 206 // A function not defined within a class will always return to its 207 // lexical context. 208 if (!isa<CXXRecordDecl>(DC)) 209 return DC; 210 211 // A C++ inline method/friend is parsed *after* the topmost class 212 // it was declared in is fully parsed ("complete"); the topmost 213 // class is the context we need to return to. 214 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 215 DC = RD; 216 217 // Return the declaration context of the topmost class the inline method is 218 // declared in. 219 return DC; 220 } 221 222 if (isa<ObjCMethodDecl>(DC)) 223 return Context.getTranslationUnitDecl(); 224 225 return DC->getLexicalParent(); 226} 227 228void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 229 assert(getContainingDC(DC) == CurContext && 230 "The next DeclContext should be lexically contained in the current one."); 231 CurContext = DC; 232 S->setEntity(DC); 233} 234 235void Sema::PopDeclContext() { 236 assert(CurContext && "DeclContext imbalance!"); 237 238 CurContext = getContainingDC(CurContext); 239} 240 241/// EnterDeclaratorContext - Used when we must lookup names in the context 242/// of a declarator's nested name specifier. 243void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 244 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 245 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 246 CurContext = DC; 247 assert(CurContext && "No context?"); 248 S->setEntity(CurContext); 249} 250 251void Sema::ExitDeclaratorContext(Scope *S) { 252 S->setEntity(PreDeclaratorDC); 253 PreDeclaratorDC = 0; 254 255 // Reset CurContext to the nearest enclosing context. 256 while (!S->getEntity() && S->getParent()) 257 S = S->getParent(); 258 CurContext = static_cast<DeclContext*>(S->getEntity()); 259 assert(CurContext && "No context?"); 260} 261 262/// \brief Determine whether we allow overloading of the function 263/// PrevDecl with another declaration. 264/// 265/// This routine determines whether overloading is possible, not 266/// whether some new function is actually an overload. It will return 267/// true in C++ (where we can always provide overloads) or, as an 268/// extension, in C when the previous function is already an 269/// overloaded function declaration or has the "overloadable" 270/// attribute. 271static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 272 if (Context.getLangOptions().CPlusPlus) 273 return true; 274 275 if (isa<OverloadedFunctionDecl>(PrevDecl)) 276 return true; 277 278 return PrevDecl->getAttr<OverloadableAttr>() != 0; 279} 280 281/// Add this decl to the scope shadowed decl chains. 282void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 283 // Move up the scope chain until we find the nearest enclosing 284 // non-transparent context. The declaration will be introduced into this 285 // scope. 286 while (S->getEntity() && 287 ((DeclContext *)S->getEntity())->isTransparentContext()) 288 S = S->getParent(); 289 290 S->AddDecl(DeclPtrTy::make(D)); 291 292 // Add scoped declarations into their context, so that they can be 293 // found later. Declarations without a context won't be inserted 294 // into any context. 295 CurContext->addDecl(D); 296 297 // C++ [basic.scope]p4: 298 // -- exactly one declaration shall declare a class name or 299 // enumeration name that is not a typedef name and the other 300 // declarations shall all refer to the same object or 301 // enumerator, or all refer to functions and function templates; 302 // in this case the class name or enumeration name is hidden. 303 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 304 // We are pushing the name of a tag (enum or class). 305 if (CurContext->getLookupContext() 306 == TD->getDeclContext()->getLookupContext()) { 307 // We're pushing the tag into the current context, which might 308 // require some reshuffling in the identifier resolver. 309 IdentifierResolver::iterator 310 I = IdResolver.begin(TD->getDeclName()), 311 IEnd = IdResolver.end(); 312 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 313 NamedDecl *PrevDecl = *I; 314 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 315 PrevDecl = *I, ++I) { 316 if (TD->declarationReplaces(*I)) { 317 // This is a redeclaration. Remove it from the chain and 318 // break out, so that we'll add in the shadowed 319 // declaration. 320 S->RemoveDecl(DeclPtrTy::make(*I)); 321 if (PrevDecl == *I) { 322 IdResolver.RemoveDecl(*I); 323 IdResolver.AddDecl(TD); 324 return; 325 } else { 326 IdResolver.RemoveDecl(*I); 327 break; 328 } 329 } 330 } 331 332 // There is already a declaration with the same name in the same 333 // scope, which is not a tag declaration. It must be found 334 // before we find the new declaration, so insert the new 335 // declaration at the end of the chain. 336 IdResolver.AddShadowedDecl(TD, PrevDecl); 337 338 return; 339 } 340 } 341 } else if ((isa<FunctionDecl>(D) && 342 AllowOverloadingOfFunction(D, Context)) || 343 isa<FunctionTemplateDecl>(D)) { 344 // We are pushing the name of a function or function template, 345 // which might be an overloaded name. 346 IdentifierResolver::iterator Redecl 347 = std::find_if(IdResolver.begin(D->getDeclName()), 348 IdResolver.end(), 349 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 350 D)); 351 if (Redecl != IdResolver.end() && 352 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 353 // There is already a declaration of a function on our 354 // IdResolver chain. Replace it with this declaration. 355 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 356 IdResolver.RemoveDecl(*Redecl); 357 } 358 } else if (isa<ObjCInterfaceDecl>(D)) { 359 // We're pushing an Objective-C interface into the current 360 // context. If there is already an alias declaration, remove it first. 361 for (IdentifierResolver::iterator 362 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 363 I != IEnd; ++I) { 364 if (isa<ObjCCompatibleAliasDecl>(*I)) { 365 S->RemoveDecl(DeclPtrTy::make(*I)); 366 IdResolver.RemoveDecl(*I); 367 break; 368 } 369 } 370 } 371 372 IdResolver.AddDecl(D); 373} 374 375void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 376 if (S->decl_empty()) return; 377 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 378 "Scope shouldn't contain decls!"); 379 380 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 381 I != E; ++I) { 382 Decl *TmpD = (*I).getAs<Decl>(); 383 assert(TmpD && "This decl didn't get pushed??"); 384 385 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 386 NamedDecl *D = cast<NamedDecl>(TmpD); 387 388 if (!D->getDeclName()) continue; 389 390 // Remove this name from our lexical scope. 391 IdResolver.RemoveDecl(D); 392 } 393} 394 395/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 396/// return 0 if one not found. 397ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 398 // The third "scope" argument is 0 since we aren't enabling lazy built-in 399 // creation from this context. 400 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 401 402 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 403} 404 405/// getNonFieldDeclScope - Retrieves the innermost scope, starting 406/// from S, where a non-field would be declared. This routine copes 407/// with the difference between C and C++ scoping rules in structs and 408/// unions. For example, the following code is well-formed in C but 409/// ill-formed in C++: 410/// @code 411/// struct S6 { 412/// enum { BAR } e; 413/// }; 414/// 415/// void test_S6() { 416/// struct S6 a; 417/// a.e = BAR; 418/// } 419/// @endcode 420/// For the declaration of BAR, this routine will return a different 421/// scope. The scope S will be the scope of the unnamed enumeration 422/// within S6. In C++, this routine will return the scope associated 423/// with S6, because the enumeration's scope is a transparent 424/// context but structures can contain non-field names. In C, this 425/// routine will return the translation unit scope, since the 426/// enumeration's scope is a transparent context and structures cannot 427/// contain non-field names. 428Scope *Sema::getNonFieldDeclScope(Scope *S) { 429 while (((S->getFlags() & Scope::DeclScope) == 0) || 430 (S->getEntity() && 431 ((DeclContext *)S->getEntity())->isTransparentContext()) || 432 (S->isClassScope() && !getLangOptions().CPlusPlus)) 433 S = S->getParent(); 434 return S; 435} 436 437void Sema::InitBuiltinVaListType() { 438 if (!Context.getBuiltinVaListType().isNull()) 439 return; 440 441 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 442 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 443 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 444 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 445} 446 447/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 448/// file scope. lazily create a decl for it. ForRedeclaration is true 449/// if we're creating this built-in in anticipation of redeclaring the 450/// built-in. 451NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 452 Scope *S, bool ForRedeclaration, 453 SourceLocation Loc) { 454 Builtin::ID BID = (Builtin::ID)bid; 455 456 if (Context.BuiltinInfo.hasVAListUse(BID)) 457 InitBuiltinVaListType(); 458 459 ASTContext::GetBuiltinTypeError Error; 460 QualType R = Context.GetBuiltinType(BID, Error); 461 switch (Error) { 462 case ASTContext::GE_None: 463 // Okay 464 break; 465 466 case ASTContext::GE_Missing_stdio: 467 if (ForRedeclaration) 468 Diag(Loc, diag::err_implicit_decl_requires_stdio) 469 << Context.BuiltinInfo.GetName(BID); 470 return 0; 471 472 case ASTContext::GE_Missing_setjmp: 473 if (ForRedeclaration) 474 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 475 << Context.BuiltinInfo.GetName(BID); 476 return 0; 477 } 478 479 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 480 Diag(Loc, diag::ext_implicit_lib_function_decl) 481 << Context.BuiltinInfo.GetName(BID) 482 << R; 483 if (Context.BuiltinInfo.getHeaderName(BID) && 484 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 485 != Diagnostic::Ignored) 486 Diag(Loc, diag::note_please_include_header) 487 << Context.BuiltinInfo.getHeaderName(BID) 488 << Context.BuiltinInfo.GetName(BID); 489 } 490 491 FunctionDecl *New = FunctionDecl::Create(Context, 492 Context.getTranslationUnitDecl(), 493 Loc, II, R, /*DInfo=*/0, 494 FunctionDecl::Extern, false, 495 /*hasPrototype=*/true); 496 New->setImplicit(); 497 498 // Create Decl objects for each parameter, adding them to the 499 // FunctionDecl. 500 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 501 llvm::SmallVector<ParmVarDecl*, 16> Params; 502 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 503 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 504 FT->getArgType(i), /*DInfo=*/0, 505 VarDecl::None, 0)); 506 New->setParams(Context, Params.data(), Params.size()); 507 } 508 509 AddKnownFunctionAttributes(New); 510 511 // TUScope is the translation-unit scope to insert this function into. 512 // FIXME: This is hideous. We need to teach PushOnScopeChains to 513 // relate Scopes to DeclContexts, and probably eliminate CurContext 514 // entirely, but we're not there yet. 515 DeclContext *SavedContext = CurContext; 516 CurContext = Context.getTranslationUnitDecl(); 517 PushOnScopeChains(New, TUScope); 518 CurContext = SavedContext; 519 return New; 520} 521 522/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 523/// everything from the standard library is defined. 524NamespaceDecl *Sema::GetStdNamespace() { 525 if (!StdNamespace) { 526 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 527 DeclContext *Global = Context.getTranslationUnitDecl(); 528 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 529 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 530 } 531 return StdNamespace; 532} 533 534/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 535/// same name and scope as a previous declaration 'Old'. Figure out 536/// how to resolve this situation, merging decls or emitting 537/// diagnostics as appropriate. If there was an error, set New to be invalid. 538/// 539void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 540 // If either decl is known invalid already, set the new one to be invalid and 541 // don't bother doing any merging checks. 542 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 543 return New->setInvalidDecl(); 544 545 // Allow multiple definitions for ObjC built-in typedefs. 546 // FIXME: Verify the underlying types are equivalent! 547 if (getLangOptions().ObjC1) { 548 const IdentifierInfo *TypeID = New->getIdentifier(); 549 switch (TypeID->getLength()) { 550 default: break; 551 case 2: 552 if (!TypeID->isStr("id")) 553 break; 554 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 555 // Install the built-in type for 'id', ignoring the current definition. 556 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 557 return; 558 case 5: 559 if (!TypeID->isStr("Class")) 560 break; 561 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 562 // Install the built-in type for 'Class', ignoring the current definition. 563 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 564 return; 565 case 3: 566 if (!TypeID->isStr("SEL")) 567 break; 568 Context.setObjCSelType(Context.getTypeDeclType(New)); 569 return; 570 case 8: 571 if (!TypeID->isStr("Protocol")) 572 break; 573 Context.setObjCProtoType(New->getUnderlyingType()); 574 return; 575 } 576 // Fall through - the typedef name was not a builtin type. 577 } 578 // Verify the old decl was also a type. 579 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 580 if (!Old) { 581 Diag(New->getLocation(), diag::err_redefinition_different_kind) 582 << New->getDeclName(); 583 if (OldD->getLocation().isValid()) 584 Diag(OldD->getLocation(), diag::note_previous_definition); 585 return New->setInvalidDecl(); 586 } 587 588 // Determine the "old" type we'll use for checking and diagnostics. 589 QualType OldType; 590 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 591 OldType = OldTypedef->getUnderlyingType(); 592 else 593 OldType = Context.getTypeDeclType(Old); 594 595 // If the typedef types are not identical, reject them in all languages and 596 // with any extensions enabled. 597 598 if (OldType != New->getUnderlyingType() && 599 Context.getCanonicalType(OldType) != 600 Context.getCanonicalType(New->getUnderlyingType())) { 601 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 602 << New->getUnderlyingType() << OldType; 603 if (Old->getLocation().isValid()) 604 Diag(Old->getLocation(), diag::note_previous_definition); 605 return New->setInvalidDecl(); 606 } 607 608 if (getLangOptions().Microsoft) 609 return; 610 611 // C++ [dcl.typedef]p2: 612 // In a given non-class scope, a typedef specifier can be used to 613 // redefine the name of any type declared in that scope to refer 614 // to the type to which it already refers. 615 if (getLangOptions().CPlusPlus) { 616 if (!isa<CXXRecordDecl>(CurContext)) 617 return; 618 Diag(New->getLocation(), diag::err_redefinition) 619 << New->getDeclName(); 620 Diag(Old->getLocation(), diag::note_previous_definition); 621 return New->setInvalidDecl(); 622 } 623 624 // If we have a redefinition of a typedef in C, emit a warning. This warning 625 // is normally mapped to an error, but can be controlled with 626 // -Wtypedef-redefinition. If either the original or the redefinition is 627 // in a system header, don't emit this for compatibility with GCC. 628 if (PP.getDiagnostics().getSuppressSystemWarnings() && 629 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 630 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 631 return; 632 633 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 634 << New->getDeclName(); 635 Diag(Old->getLocation(), diag::note_previous_definition); 636 return; 637} 638 639/// DeclhasAttr - returns true if decl Declaration already has the target 640/// attribute. 641static bool 642DeclHasAttr(const Decl *decl, const Attr *target) { 643 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 644 if (attr->getKind() == target->getKind()) 645 return true; 646 647 return false; 648} 649 650/// MergeAttributes - append attributes from the Old decl to the New one. 651static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 652 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 653 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 654 Attr *NewAttr = attr->clone(C); 655 NewAttr->setInherited(true); 656 New->addAttr(NewAttr); 657 } 658 } 659} 660 661/// Used in MergeFunctionDecl to keep track of function parameters in 662/// C. 663struct GNUCompatibleParamWarning { 664 ParmVarDecl *OldParm; 665 ParmVarDecl *NewParm; 666 QualType PromotedType; 667}; 668 669/// MergeFunctionDecl - We just parsed a function 'New' from 670/// declarator D which has the same name and scope as a previous 671/// declaration 'Old'. Figure out how to resolve this situation, 672/// merging decls or emitting diagnostics as appropriate. 673/// 674/// In C++, New and Old must be declarations that are not 675/// overloaded. Use IsOverload to determine whether New and Old are 676/// overloaded, and to select the Old declaration that New should be 677/// merged with. 678/// 679/// Returns true if there was an error, false otherwise. 680bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 681 assert(!isa<OverloadedFunctionDecl>(OldD) && 682 "Cannot merge with an overloaded function declaration"); 683 684 // Verify the old decl was also a function. 685 FunctionDecl *Old = 0; 686 if (FunctionTemplateDecl *OldFunctionTemplate 687 = dyn_cast<FunctionTemplateDecl>(OldD)) 688 Old = OldFunctionTemplate->getTemplatedDecl(); 689 else 690 Old = dyn_cast<FunctionDecl>(OldD); 691 if (!Old) { 692 Diag(New->getLocation(), diag::err_redefinition_different_kind) 693 << New->getDeclName(); 694 Diag(OldD->getLocation(), diag::note_previous_definition); 695 return true; 696 } 697 698 // Determine whether the previous declaration was a definition, 699 // implicit declaration, or a declaration. 700 diag::kind PrevDiag; 701 if (Old->isThisDeclarationADefinition()) 702 PrevDiag = diag::note_previous_definition; 703 else if (Old->isImplicit()) 704 PrevDiag = diag::note_previous_implicit_declaration; 705 else 706 PrevDiag = diag::note_previous_declaration; 707 708 QualType OldQType = Context.getCanonicalType(Old->getType()); 709 QualType NewQType = Context.getCanonicalType(New->getType()); 710 711 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 712 New->getStorageClass() == FunctionDecl::Static && 713 Old->getStorageClass() != FunctionDecl::Static) { 714 Diag(New->getLocation(), diag::err_static_non_static) 715 << New; 716 Diag(Old->getLocation(), PrevDiag); 717 return true; 718 } 719 720 if (getLangOptions().CPlusPlus) { 721 // (C++98 13.1p2): 722 // Certain function declarations cannot be overloaded: 723 // -- Function declarations that differ only in the return type 724 // cannot be overloaded. 725 QualType OldReturnType 726 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 727 QualType NewReturnType 728 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 729 if (OldReturnType != NewReturnType) { 730 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 731 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 732 return true; 733 } 734 735 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 736 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 737 if (OldMethod && NewMethod && 738 NewMethod->getLexicalDeclContext()->isRecord()) { 739 // -- Member function declarations with the same name and the 740 // same parameter types cannot be overloaded if any of them 741 // is a static member function declaration. 742 if (OldMethod->isStatic() || NewMethod->isStatic()) { 743 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 744 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 745 return true; 746 } 747 748 // C++ [class.mem]p1: 749 // [...] A member shall not be declared twice in the 750 // member-specification, except that a nested class or member 751 // class template can be declared and then later defined. 752 unsigned NewDiag; 753 if (isa<CXXConstructorDecl>(OldMethod)) 754 NewDiag = diag::err_constructor_redeclared; 755 else if (isa<CXXDestructorDecl>(NewMethod)) 756 NewDiag = diag::err_destructor_redeclared; 757 else if (isa<CXXConversionDecl>(NewMethod)) 758 NewDiag = diag::err_conv_function_redeclared; 759 else 760 NewDiag = diag::err_member_redeclared; 761 762 Diag(New->getLocation(), NewDiag); 763 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 764 } 765 766 // (C++98 8.3.5p3): 767 // All declarations for a function shall agree exactly in both the 768 // return type and the parameter-type-list. 769 if (OldQType == NewQType) 770 return MergeCompatibleFunctionDecls(New, Old); 771 772 // Fall through for conflicting redeclarations and redefinitions. 773 } 774 775 // C: Function types need to be compatible, not identical. This handles 776 // duplicate function decls like "void f(int); void f(enum X);" properly. 777 if (!getLangOptions().CPlusPlus && 778 Context.typesAreCompatible(OldQType, NewQType)) { 779 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 780 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 781 const FunctionProtoType *OldProto = 0; 782 if (isa<FunctionNoProtoType>(NewFuncType) && 783 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 784 // The old declaration provided a function prototype, but the 785 // new declaration does not. Merge in the prototype. 786 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 787 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 788 OldProto->arg_type_end()); 789 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 790 ParamTypes.data(), ParamTypes.size(), 791 OldProto->isVariadic(), 792 OldProto->getTypeQuals()); 793 New->setType(NewQType); 794 New->setHasInheritedPrototype(); 795 796 // Synthesize a parameter for each argument type. 797 llvm::SmallVector<ParmVarDecl*, 16> Params; 798 for (FunctionProtoType::arg_type_iterator 799 ParamType = OldProto->arg_type_begin(), 800 ParamEnd = OldProto->arg_type_end(); 801 ParamType != ParamEnd; ++ParamType) { 802 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 803 SourceLocation(), 0, 804 *ParamType, /*DInfo=*/0, 805 VarDecl::None, 0); 806 Param->setImplicit(); 807 Params.push_back(Param); 808 } 809 810 New->setParams(Context, Params.data(), Params.size()); 811 } 812 813 return MergeCompatibleFunctionDecls(New, Old); 814 } 815 816 // GNU C permits a K&R definition to follow a prototype declaration 817 // if the declared types of the parameters in the K&R definition 818 // match the types in the prototype declaration, even when the 819 // promoted types of the parameters from the K&R definition differ 820 // from the types in the prototype. GCC then keeps the types from 821 // the prototype. 822 // 823 // If a variadic prototype is followed by a non-variadic K&R definition, 824 // the K&R definition becomes variadic. This is sort of an edge case, but 825 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 826 // C99 6.9.1p8. 827 if (!getLangOptions().CPlusPlus && 828 Old->hasPrototype() && !New->hasPrototype() && 829 New->getType()->getAsFunctionProtoType() && 830 Old->getNumParams() == New->getNumParams()) { 831 llvm::SmallVector<QualType, 16> ArgTypes; 832 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 833 const FunctionProtoType *OldProto 834 = Old->getType()->getAsFunctionProtoType(); 835 const FunctionProtoType *NewProto 836 = New->getType()->getAsFunctionProtoType(); 837 838 // Determine whether this is the GNU C extension. 839 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 840 NewProto->getResultType()); 841 bool LooseCompatible = !MergedReturn.isNull(); 842 for (unsigned Idx = 0, End = Old->getNumParams(); 843 LooseCompatible && Idx != End; ++Idx) { 844 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 845 ParmVarDecl *NewParm = New->getParamDecl(Idx); 846 if (Context.typesAreCompatible(OldParm->getType(), 847 NewProto->getArgType(Idx))) { 848 ArgTypes.push_back(NewParm->getType()); 849 } else if (Context.typesAreCompatible(OldParm->getType(), 850 NewParm->getType())) { 851 GNUCompatibleParamWarning Warn 852 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 853 Warnings.push_back(Warn); 854 ArgTypes.push_back(NewParm->getType()); 855 } else 856 LooseCompatible = false; 857 } 858 859 if (LooseCompatible) { 860 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 861 Diag(Warnings[Warn].NewParm->getLocation(), 862 diag::ext_param_promoted_not_compatible_with_prototype) 863 << Warnings[Warn].PromotedType 864 << Warnings[Warn].OldParm->getType(); 865 Diag(Warnings[Warn].OldParm->getLocation(), 866 diag::note_previous_declaration); 867 } 868 869 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 870 ArgTypes.size(), 871 OldProto->isVariadic(), 0)); 872 return MergeCompatibleFunctionDecls(New, Old); 873 } 874 875 // Fall through to diagnose conflicting types. 876 } 877 878 // A function that has already been declared has been redeclared or defined 879 // with a different type- show appropriate diagnostic 880 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 881 // The user has declared a builtin function with an incompatible 882 // signature. 883 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 884 // The function the user is redeclaring is a library-defined 885 // function like 'malloc' or 'printf'. Warn about the 886 // redeclaration, then pretend that we don't know about this 887 // library built-in. 888 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 889 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 890 << Old << Old->getType(); 891 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 892 Old->setInvalidDecl(); 893 return false; 894 } 895 896 PrevDiag = diag::note_previous_builtin_declaration; 897 } 898 899 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 900 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 901 return true; 902} 903 904/// \brief Completes the merge of two function declarations that are 905/// known to be compatible. 906/// 907/// This routine handles the merging of attributes and other 908/// properties of function declarations form the old declaration to 909/// the new declaration, once we know that New is in fact a 910/// redeclaration of Old. 911/// 912/// \returns false 913bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 914 // Merge the attributes 915 MergeAttributes(New, Old, Context); 916 917 // Merge the storage class. 918 if (Old->getStorageClass() != FunctionDecl::Extern) 919 New->setStorageClass(Old->getStorageClass()); 920 921 // Merge "inline" 922 if (Old->isInline()) 923 New->setInline(true); 924 925 // If this function declaration by itself qualifies as a C99 inline 926 // definition (C99 6.7.4p6), but the previous definition did not, 927 // then the function is not a C99 inline definition. 928 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 929 New->setC99InlineDefinition(false); 930 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 931 // Mark all preceding definitions as not being C99 inline definitions. 932 for (const FunctionDecl *Prev = Old; Prev; 933 Prev = Prev->getPreviousDeclaration()) 934 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 935 } 936 937 // Merge "pure" flag. 938 if (Old->isPure()) 939 New->setPure(); 940 941 // Merge the "deleted" flag. 942 if (Old->isDeleted()) 943 New->setDeleted(); 944 945 if (getLangOptions().CPlusPlus) 946 return MergeCXXFunctionDecl(New, Old); 947 948 return false; 949} 950 951/// MergeVarDecl - We just parsed a variable 'New' which has the same name 952/// and scope as a previous declaration 'Old'. Figure out how to resolve this 953/// situation, merging decls or emitting diagnostics as appropriate. 954/// 955/// Tentative definition rules (C99 6.9.2p2) are checked by 956/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 957/// definitions here, since the initializer hasn't been attached. 958/// 959void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 960 // If either decl is invalid, make sure the new one is marked invalid and 961 // don't do any other checking. 962 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 963 return New->setInvalidDecl(); 964 965 // Verify the old decl was also a variable. 966 VarDecl *Old = dyn_cast<VarDecl>(OldD); 967 if (!Old) { 968 Diag(New->getLocation(), diag::err_redefinition_different_kind) 969 << New->getDeclName(); 970 Diag(OldD->getLocation(), diag::note_previous_definition); 971 return New->setInvalidDecl(); 972 } 973 974 MergeAttributes(New, Old, Context); 975 976 // Merge the types 977 QualType MergedT; 978 if (getLangOptions().CPlusPlus) { 979 if (Context.hasSameType(New->getType(), Old->getType())) 980 MergedT = New->getType(); 981 } else { 982 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 983 } 984 if (MergedT.isNull()) { 985 Diag(New->getLocation(), diag::err_redefinition_different_type) 986 << New->getDeclName(); 987 Diag(Old->getLocation(), diag::note_previous_definition); 988 return New->setInvalidDecl(); 989 } 990 New->setType(MergedT); 991 992 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 993 if (New->getStorageClass() == VarDecl::Static && 994 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 995 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 996 Diag(Old->getLocation(), diag::note_previous_definition); 997 return New->setInvalidDecl(); 998 } 999 // C99 6.2.2p4: 1000 // For an identifier declared with the storage-class specifier 1001 // extern in a scope in which a prior declaration of that 1002 // identifier is visible,23) if the prior declaration specifies 1003 // internal or external linkage, the linkage of the identifier at 1004 // the later declaration is the same as the linkage specified at 1005 // the prior declaration. If no prior declaration is visible, or 1006 // if the prior declaration specifies no linkage, then the 1007 // identifier has external linkage. 1008 if (New->hasExternalStorage() && Old->hasLinkage()) 1009 /* Okay */; 1010 else if (New->getStorageClass() != VarDecl::Static && 1011 Old->getStorageClass() == VarDecl::Static) { 1012 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1013 Diag(Old->getLocation(), diag::note_previous_definition); 1014 return New->setInvalidDecl(); 1015 } 1016 1017 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1018 1019 // FIXME: The test for external storage here seems wrong? We still 1020 // need to check for mismatches. 1021 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1022 // Don't complain about out-of-line definitions of static members. 1023 !(Old->getLexicalDeclContext()->isRecord() && 1024 !New->getLexicalDeclContext()->isRecord())) { 1025 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1026 Diag(Old->getLocation(), diag::note_previous_definition); 1027 return New->setInvalidDecl(); 1028 } 1029 1030 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1031 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1032 Diag(Old->getLocation(), diag::note_previous_definition); 1033 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1034 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1035 Diag(Old->getLocation(), diag::note_previous_definition); 1036 } 1037 1038 // Keep a chain of previous declarations. 1039 New->setPreviousDeclaration(Old); 1040} 1041 1042/// CheckFallThrough - Check that we don't fall off the end of a 1043/// Statement that should return a value. 1044/// 1045/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1046/// MaybeFallThrough iff we might or might not fall off the end and 1047/// NeverFallThrough iff we never fall off the end of the statement. We assume 1048/// that functions not marked noreturn will return. 1049Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1050 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1051 1052 // FIXME: They should never return 0, fix that, delete this code. 1053 if (cfg == 0) 1054 return NeverFallThrough; 1055 // The CFG leaves in dead things, and we don't want to dead code paths to 1056 // confuse us, so we mark all live things first. 1057 std::queue<CFGBlock*> workq; 1058 llvm::BitVector live(cfg->getNumBlockIDs()); 1059 // Prep work queue 1060 workq.push(&cfg->getEntry()); 1061 // Solve 1062 while (!workq.empty()) { 1063 CFGBlock *item = workq.front(); 1064 workq.pop(); 1065 live.set(item->getBlockID()); 1066 for (CFGBlock::succ_iterator I=item->succ_begin(), 1067 E=item->succ_end(); 1068 I != E; 1069 ++I) { 1070 if ((*I) && !live[(*I)->getBlockID()]) { 1071 live.set((*I)->getBlockID()); 1072 workq.push(*I); 1073 } 1074 } 1075 } 1076 1077 // Now we know what is live, we check the live precessors of the exit block 1078 // and look for fall through paths, being careful to ignore normal returns, 1079 // and exceptional paths. 1080 bool HasLiveReturn = false; 1081 bool HasFakeEdge = false; 1082 bool HasPlainEdge = false; 1083 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1084 E = cfg->getExit().pred_end(); 1085 I != E; 1086 ++I) { 1087 CFGBlock& B = **I; 1088 if (!live[B.getBlockID()]) 1089 continue; 1090 if (B.size() == 0) { 1091 // A labeled empty statement, or the entry block... 1092 HasPlainEdge = true; 1093 continue; 1094 } 1095 Stmt *S = B[B.size()-1]; 1096 if (isa<ReturnStmt>(S)) { 1097 HasLiveReturn = true; 1098 continue; 1099 } 1100 if (isa<ObjCAtThrowStmt>(S)) { 1101 HasFakeEdge = true; 1102 continue; 1103 } 1104 if (isa<CXXThrowExpr>(S)) { 1105 HasFakeEdge = true; 1106 continue; 1107 } 1108 bool NoReturnEdge = false; 1109 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1110 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1111 if (CEE->getType().getNoReturnAttr()) { 1112 NoReturnEdge = true; 1113 HasFakeEdge = true; 1114 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1115 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1116 if (FD->hasAttr<NoReturnAttr>()) { 1117 NoReturnEdge = true; 1118 HasFakeEdge = true; 1119 } 1120 } 1121 } 1122 } 1123 // FIXME: Add noreturn message sends. 1124 if (NoReturnEdge == false) 1125 HasPlainEdge = true; 1126 } 1127 if (!HasPlainEdge) 1128 return NeverFallThrough; 1129 if (HasFakeEdge || HasLiveReturn) 1130 return MaybeFallThrough; 1131 // This says AlwaysFallThrough for calls to functions that are not marked 1132 // noreturn, that don't return. If people would like this warning to be more 1133 // accurate, such functions should be marked as noreturn. 1134 return AlwaysFallThrough; 1135} 1136 1137/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1138/// function that should return a value. Check that we don't fall off the end 1139/// of a noreturn function. We assume that functions and blocks not marked 1140/// noreturn will return. 1141void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1142 // FIXME: Would be nice if we had a better way to control cascading errors, 1143 // but for now, avoid them. The problem is that when Parse sees: 1144 // int foo() { return a; } 1145 // The return is eaten and the Sema code sees just: 1146 // int foo() { } 1147 // which this code would then warn about. 1148 if (getDiagnostics().hasErrorOccurred()) 1149 return; 1150 bool ReturnsVoid = false; 1151 bool HasNoReturn = false; 1152 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1153 if (FD->getResultType()->isVoidType()) 1154 ReturnsVoid = true; 1155 if (FD->hasAttr<NoReturnAttr>()) 1156 HasNoReturn = true; 1157 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1158 if (MD->getResultType()->isVoidType()) 1159 ReturnsVoid = true; 1160 if (MD->hasAttr<NoReturnAttr>()) 1161 HasNoReturn = true; 1162 } 1163 1164 // Short circuit for compilation speed. 1165 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1166 == Diagnostic::Ignored || ReturnsVoid) 1167 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1168 == Diagnostic::Ignored || !HasNoReturn) 1169 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1170 == Diagnostic::Ignored || !ReturnsVoid)) 1171 return; 1172 // FIXME: Funtion try block 1173 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1174 switch (CheckFallThrough(Body)) { 1175 case MaybeFallThrough: 1176 if (HasNoReturn) 1177 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1178 else if (!ReturnsVoid) 1179 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1180 break; 1181 case AlwaysFallThrough: 1182 if (HasNoReturn) 1183 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1184 else if (!ReturnsVoid) 1185 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1186 break; 1187 case NeverFallThrough: 1188 if (ReturnsVoid) 1189 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1190 break; 1191 } 1192 } 1193} 1194 1195/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1196/// that should return a value. Check that we don't fall off the end of a 1197/// noreturn block. We assume that functions and blocks not marked noreturn 1198/// will return. 1199void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1200 // FIXME: Would be nice if we had a better way to control cascading errors, 1201 // but for now, avoid them. The problem is that when Parse sees: 1202 // int foo() { return a; } 1203 // The return is eaten and the Sema code sees just: 1204 // int foo() { } 1205 // which this code would then warn about. 1206 if (getDiagnostics().hasErrorOccurred()) 1207 return; 1208 bool ReturnsVoid = false; 1209 bool HasNoReturn = false; 1210 if (const FunctionType *FT = BlockTy->getPointeeType()->getAsFunctionType()) { 1211 if (FT->getResultType()->isVoidType()) 1212 ReturnsVoid = true; 1213 if (FT->getNoReturnAttr()) 1214 HasNoReturn = true; 1215 } 1216 1217 // Short circuit for compilation speed. 1218 if (ReturnsVoid 1219 && !HasNoReturn 1220 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1221 == Diagnostic::Ignored || !ReturnsVoid)) 1222 return; 1223 // FIXME: Funtion try block 1224 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1225 switch (CheckFallThrough(Body)) { 1226 case MaybeFallThrough: 1227 if (HasNoReturn) 1228 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1229 else if (!ReturnsVoid) 1230 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1231 break; 1232 case AlwaysFallThrough: 1233 if (HasNoReturn) 1234 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1235 else if (!ReturnsVoid) 1236 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1237 break; 1238 case NeverFallThrough: 1239 if (ReturnsVoid) 1240 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1241 break; 1242 } 1243 } 1244} 1245 1246/// CheckParmsForFunctionDef - Check that the parameters of the given 1247/// function are appropriate for the definition of a function. This 1248/// takes care of any checks that cannot be performed on the 1249/// declaration itself, e.g., that the types of each of the function 1250/// parameters are complete. 1251bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1252 bool HasInvalidParm = false; 1253 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1254 ParmVarDecl *Param = FD->getParamDecl(p); 1255 1256 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1257 // function declarator that is part of a function definition of 1258 // that function shall not have incomplete type. 1259 // 1260 // This is also C++ [dcl.fct]p6. 1261 if (!Param->isInvalidDecl() && 1262 RequireCompleteType(Param->getLocation(), Param->getType(), 1263 diag::err_typecheck_decl_incomplete_type)) { 1264 Param->setInvalidDecl(); 1265 HasInvalidParm = true; 1266 } 1267 1268 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1269 // declaration of each parameter shall include an identifier. 1270 if (Param->getIdentifier() == 0 && 1271 !Param->isImplicit() && 1272 !getLangOptions().CPlusPlus) 1273 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1274 } 1275 1276 return HasInvalidParm; 1277} 1278 1279/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1280/// no declarator (e.g. "struct foo;") is parsed. 1281Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1282 // FIXME: Error on auto/register at file scope 1283 // FIXME: Error on inline/virtual/explicit 1284 // FIXME: Error on invalid restrict 1285 // FIXME: Warn on useless __thread 1286 // FIXME: Warn on useless const/volatile 1287 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1288 // FIXME: Warn on useless attributes 1289 TagDecl *Tag = 0; 1290 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1291 DS.getTypeSpecType() == DeclSpec::TST_struct || 1292 DS.getTypeSpecType() == DeclSpec::TST_union || 1293 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1294 if (!DS.getTypeRep()) // We probably had an error 1295 return DeclPtrTy(); 1296 1297 // Note that the above type specs guarantee that the 1298 // type rep is a Decl, whereas in many of the others 1299 // it's a Type. 1300 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1301 } 1302 1303 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1304 if (!Record->getDeclName() && Record->isDefinition() && 1305 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1306 if (getLangOptions().CPlusPlus || 1307 Record->getDeclContext()->isRecord()) 1308 return BuildAnonymousStructOrUnion(S, DS, Record); 1309 1310 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1311 << DS.getSourceRange(); 1312 } 1313 1314 // Microsoft allows unnamed struct/union fields. Don't complain 1315 // about them. 1316 // FIXME: Should we support Microsoft's extensions in this area? 1317 if (Record->getDeclName() && getLangOptions().Microsoft) 1318 return DeclPtrTy::make(Tag); 1319 } 1320 1321 if (!DS.isMissingDeclaratorOk() && 1322 DS.getTypeSpecType() != DeclSpec::TST_error) { 1323 // Warn about typedefs of enums without names, since this is an 1324 // extension in both Microsoft an GNU. 1325 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1326 Tag && isa<EnumDecl>(Tag)) { 1327 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1328 << DS.getSourceRange(); 1329 return DeclPtrTy::make(Tag); 1330 } 1331 1332 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1333 << DS.getSourceRange(); 1334 return DeclPtrTy(); 1335 } 1336 1337 return DeclPtrTy::make(Tag); 1338} 1339 1340/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1341/// anonymous struct or union AnonRecord into the owning context Owner 1342/// and scope S. This routine will be invoked just after we realize 1343/// that an unnamed union or struct is actually an anonymous union or 1344/// struct, e.g., 1345/// 1346/// @code 1347/// union { 1348/// int i; 1349/// float f; 1350/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1351/// // f into the surrounding scope.x 1352/// @endcode 1353/// 1354/// This routine is recursive, injecting the names of nested anonymous 1355/// structs/unions into the owning context and scope as well. 1356bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1357 RecordDecl *AnonRecord) { 1358 bool Invalid = false; 1359 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1360 FEnd = AnonRecord->field_end(); 1361 F != FEnd; ++F) { 1362 if ((*F)->getDeclName()) { 1363 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1364 LookupOrdinaryName, true); 1365 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1366 // C++ [class.union]p2: 1367 // The names of the members of an anonymous union shall be 1368 // distinct from the names of any other entity in the 1369 // scope in which the anonymous union is declared. 1370 unsigned diagKind 1371 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1372 : diag::err_anonymous_struct_member_redecl; 1373 Diag((*F)->getLocation(), diagKind) 1374 << (*F)->getDeclName(); 1375 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1376 Invalid = true; 1377 } else { 1378 // C++ [class.union]p2: 1379 // For the purpose of name lookup, after the anonymous union 1380 // definition, the members of the anonymous union are 1381 // considered to have been defined in the scope in which the 1382 // anonymous union is declared. 1383 Owner->makeDeclVisibleInContext(*F); 1384 S->AddDecl(DeclPtrTy::make(*F)); 1385 IdResolver.AddDecl(*F); 1386 } 1387 } else if (const RecordType *InnerRecordType 1388 = (*F)->getType()->getAs<RecordType>()) { 1389 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1390 if (InnerRecord->isAnonymousStructOrUnion()) 1391 Invalid = Invalid || 1392 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1393 } 1394 } 1395 1396 return Invalid; 1397} 1398 1399/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1400/// anonymous structure or union. Anonymous unions are a C++ feature 1401/// (C++ [class.union]) and a GNU C extension; anonymous structures 1402/// are a GNU C and GNU C++ extension. 1403Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1404 RecordDecl *Record) { 1405 DeclContext *Owner = Record->getDeclContext(); 1406 1407 // Diagnose whether this anonymous struct/union is an extension. 1408 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1409 Diag(Record->getLocation(), diag::ext_anonymous_union); 1410 else if (!Record->isUnion()) 1411 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1412 1413 // C and C++ require different kinds of checks for anonymous 1414 // structs/unions. 1415 bool Invalid = false; 1416 if (getLangOptions().CPlusPlus) { 1417 const char* PrevSpec = 0; 1418 unsigned DiagID; 1419 // C++ [class.union]p3: 1420 // Anonymous unions declared in a named namespace or in the 1421 // global namespace shall be declared static. 1422 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1423 (isa<TranslationUnitDecl>(Owner) || 1424 (isa<NamespaceDecl>(Owner) && 1425 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1426 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1427 Invalid = true; 1428 1429 // Recover by adding 'static'. 1430 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1431 PrevSpec, DiagID); 1432 } 1433 // C++ [class.union]p3: 1434 // A storage class is not allowed in a declaration of an 1435 // anonymous union in a class scope. 1436 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1437 isa<RecordDecl>(Owner)) { 1438 Diag(DS.getStorageClassSpecLoc(), 1439 diag::err_anonymous_union_with_storage_spec); 1440 Invalid = true; 1441 1442 // Recover by removing the storage specifier. 1443 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1444 PrevSpec, DiagID); 1445 } 1446 1447 // C++ [class.union]p2: 1448 // The member-specification of an anonymous union shall only 1449 // define non-static data members. [Note: nested types and 1450 // functions cannot be declared within an anonymous union. ] 1451 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1452 MemEnd = Record->decls_end(); 1453 Mem != MemEnd; ++Mem) { 1454 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1455 // C++ [class.union]p3: 1456 // An anonymous union shall not have private or protected 1457 // members (clause 11). 1458 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1459 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1460 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1461 Invalid = true; 1462 } 1463 } else if ((*Mem)->isImplicit()) { 1464 // Any implicit members are fine. 1465 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1466 // This is a type that showed up in an 1467 // elaborated-type-specifier inside the anonymous struct or 1468 // union, but which actually declares a type outside of the 1469 // anonymous struct or union. It's okay. 1470 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1471 if (!MemRecord->isAnonymousStructOrUnion() && 1472 MemRecord->getDeclName()) { 1473 // This is a nested type declaration. 1474 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1475 << (int)Record->isUnion(); 1476 Invalid = true; 1477 } 1478 } else { 1479 // We have something that isn't a non-static data 1480 // member. Complain about it. 1481 unsigned DK = diag::err_anonymous_record_bad_member; 1482 if (isa<TypeDecl>(*Mem)) 1483 DK = diag::err_anonymous_record_with_type; 1484 else if (isa<FunctionDecl>(*Mem)) 1485 DK = diag::err_anonymous_record_with_function; 1486 else if (isa<VarDecl>(*Mem)) 1487 DK = diag::err_anonymous_record_with_static; 1488 Diag((*Mem)->getLocation(), DK) 1489 << (int)Record->isUnion(); 1490 Invalid = true; 1491 } 1492 } 1493 } 1494 1495 if (!Record->isUnion() && !Owner->isRecord()) { 1496 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1497 << (int)getLangOptions().CPlusPlus; 1498 Invalid = true; 1499 } 1500 1501 // Create a declaration for this anonymous struct/union. 1502 NamedDecl *Anon = 0; 1503 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1504 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1505 /*IdentifierInfo=*/0, 1506 Context.getTypeDeclType(Record), 1507 // FIXME: Type source info. 1508 /*DInfo=*/0, 1509 /*BitWidth=*/0, /*Mutable=*/false); 1510 Anon->setAccess(AS_public); 1511 if (getLangOptions().CPlusPlus) 1512 FieldCollector->Add(cast<FieldDecl>(Anon)); 1513 } else { 1514 VarDecl::StorageClass SC; 1515 switch (DS.getStorageClassSpec()) { 1516 default: assert(0 && "Unknown storage class!"); 1517 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1518 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1519 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1520 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1521 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1522 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1523 case DeclSpec::SCS_mutable: 1524 // mutable can only appear on non-static class members, so it's always 1525 // an error here 1526 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1527 Invalid = true; 1528 SC = VarDecl::None; 1529 break; 1530 } 1531 1532 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1533 /*IdentifierInfo=*/0, 1534 Context.getTypeDeclType(Record), 1535 // FIXME: Type source info. 1536 /*DInfo=*/0, 1537 SC); 1538 } 1539 Anon->setImplicit(); 1540 1541 // Add the anonymous struct/union object to the current 1542 // context. We'll be referencing this object when we refer to one of 1543 // its members. 1544 Owner->addDecl(Anon); 1545 1546 // Inject the members of the anonymous struct/union into the owning 1547 // context and into the identifier resolver chain for name lookup 1548 // purposes. 1549 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1550 Invalid = true; 1551 1552 // Mark this as an anonymous struct/union type. Note that we do not 1553 // do this until after we have already checked and injected the 1554 // members of this anonymous struct/union type, because otherwise 1555 // the members could be injected twice: once by DeclContext when it 1556 // builds its lookup table, and once by 1557 // InjectAnonymousStructOrUnionMembers. 1558 Record->setAnonymousStructOrUnion(true); 1559 1560 if (Invalid) 1561 Anon->setInvalidDecl(); 1562 1563 return DeclPtrTy::make(Anon); 1564} 1565 1566 1567/// GetNameForDeclarator - Determine the full declaration name for the 1568/// given Declarator. 1569DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1570 switch (D.getKind()) { 1571 case Declarator::DK_Abstract: 1572 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1573 return DeclarationName(); 1574 1575 case Declarator::DK_Normal: 1576 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1577 return DeclarationName(D.getIdentifier()); 1578 1579 case Declarator::DK_Constructor: { 1580 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1581 return Context.DeclarationNames.getCXXConstructorName( 1582 Context.getCanonicalType(Ty)); 1583 } 1584 1585 case Declarator::DK_Destructor: { 1586 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1587 return Context.DeclarationNames.getCXXDestructorName( 1588 Context.getCanonicalType(Ty)); 1589 } 1590 1591 case Declarator::DK_Conversion: { 1592 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1593 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1594 return Context.DeclarationNames.getCXXConversionFunctionName( 1595 Context.getCanonicalType(Ty)); 1596 } 1597 1598 case Declarator::DK_Operator: 1599 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1600 return Context.DeclarationNames.getCXXOperatorName( 1601 D.getOverloadedOperator()); 1602 } 1603 1604 assert(false && "Unknown name kind"); 1605 return DeclarationName(); 1606} 1607 1608/// isNearlyMatchingFunction - Determine whether the C++ functions 1609/// Declaration and Definition are "nearly" matching. This heuristic 1610/// is used to improve diagnostics in the case where an out-of-line 1611/// function definition doesn't match any declaration within 1612/// the class or namespace. 1613static bool isNearlyMatchingFunction(ASTContext &Context, 1614 FunctionDecl *Declaration, 1615 FunctionDecl *Definition) { 1616 if (Declaration->param_size() != Definition->param_size()) 1617 return false; 1618 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1619 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1620 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1621 1622 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1623 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1624 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1625 return false; 1626 } 1627 1628 return true; 1629} 1630 1631Sema::DeclPtrTy 1632Sema::HandleDeclarator(Scope *S, Declarator &D, 1633 MultiTemplateParamsArg TemplateParamLists, 1634 bool IsFunctionDefinition) { 1635 DeclarationName Name = GetNameForDeclarator(D); 1636 1637 // All of these full declarators require an identifier. If it doesn't have 1638 // one, the ParsedFreeStandingDeclSpec action should be used. 1639 if (!Name) { 1640 if (!D.isInvalidType()) // Reject this if we think it is valid. 1641 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1642 diag::err_declarator_need_ident) 1643 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1644 return DeclPtrTy(); 1645 } 1646 1647 // The scope passed in may not be a decl scope. Zip up the scope tree until 1648 // we find one that is. 1649 while ((S->getFlags() & Scope::DeclScope) == 0 || 1650 (S->getFlags() & Scope::TemplateParamScope) != 0) 1651 S = S->getParent(); 1652 1653 // If this is an out-of-line definition of a member of a class template 1654 // or class template partial specialization, we may need to rebuild the 1655 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1656 // for more information. 1657 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1658 // handle expressions properly. 1659 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1660 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1661 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1662 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1663 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1664 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1665 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1666 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1667 // FIXME: Preserve type source info. 1668 QualType T = GetTypeFromParser(DS.getTypeRep()); 1669 EnterDeclaratorContext(S, DC); 1670 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1671 ExitDeclaratorContext(S); 1672 if (T.isNull()) 1673 return DeclPtrTy(); 1674 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1675 } 1676 } 1677 1678 DeclContext *DC; 1679 NamedDecl *PrevDecl; 1680 NamedDecl *New; 1681 1682 DeclaratorInfo *DInfo = 0; 1683 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1684 1685 // See if this is a redefinition of a variable in the same scope. 1686 if (D.getCXXScopeSpec().isInvalid()) { 1687 DC = CurContext; 1688 PrevDecl = 0; 1689 D.setInvalidType(); 1690 } else if (!D.getCXXScopeSpec().isSet()) { 1691 LookupNameKind NameKind = LookupOrdinaryName; 1692 1693 // If the declaration we're planning to build will be a function 1694 // or object with linkage, then look for another declaration with 1695 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1696 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1697 /* Do nothing*/; 1698 else if (R->isFunctionType()) { 1699 if (CurContext->isFunctionOrMethod() || 1700 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1701 NameKind = LookupRedeclarationWithLinkage; 1702 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1703 NameKind = LookupRedeclarationWithLinkage; 1704 else if (CurContext->getLookupContext()->isTranslationUnit() && 1705 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1706 NameKind = LookupRedeclarationWithLinkage; 1707 1708 DC = CurContext; 1709 PrevDecl = LookupName(S, Name, NameKind, true, 1710 NameKind == LookupRedeclarationWithLinkage, 1711 D.getIdentifierLoc()); 1712 } else { // Something like "int foo::x;" 1713 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1714 1715 if (!DC) { 1716 // If we could not compute the declaration context, it's because the 1717 // declaration context is dependent but does not refer to a class, 1718 // class template, or class template partial specialization. Complain 1719 // and return early, to avoid the coming semantic disaster. 1720 Diag(D.getIdentifierLoc(), 1721 diag::err_template_qualified_declarator_no_match) 1722 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1723 << D.getCXXScopeSpec().getRange(); 1724 return DeclPtrTy(); 1725 } 1726 1727 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1728 1729 // C++ 7.3.1.2p2: 1730 // Members (including explicit specializations of templates) of a named 1731 // namespace can also be defined outside that namespace by explicit 1732 // qualification of the name being defined, provided that the entity being 1733 // defined was already declared in the namespace and the definition appears 1734 // after the point of declaration in a namespace that encloses the 1735 // declarations namespace. 1736 // 1737 // Note that we only check the context at this point. We don't yet 1738 // have enough information to make sure that PrevDecl is actually 1739 // the declaration we want to match. For example, given: 1740 // 1741 // class X { 1742 // void f(); 1743 // void f(float); 1744 // }; 1745 // 1746 // void X::f(int) { } // ill-formed 1747 // 1748 // In this case, PrevDecl will point to the overload set 1749 // containing the two f's declared in X, but neither of them 1750 // matches. 1751 1752 // First check whether we named the global scope. 1753 if (isa<TranslationUnitDecl>(DC)) { 1754 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1755 << Name << D.getCXXScopeSpec().getRange(); 1756 } else if (!CurContext->Encloses(DC)) { 1757 // The qualifying scope doesn't enclose the original declaration. 1758 // Emit diagnostic based on current scope. 1759 SourceLocation L = D.getIdentifierLoc(); 1760 SourceRange R = D.getCXXScopeSpec().getRange(); 1761 if (isa<FunctionDecl>(CurContext)) 1762 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1763 else 1764 Diag(L, diag::err_invalid_declarator_scope) 1765 << Name << cast<NamedDecl>(DC) << R; 1766 D.setInvalidType(); 1767 } 1768 } 1769 1770 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1771 // Maybe we will complain about the shadowed template parameter. 1772 if (!D.isInvalidType()) 1773 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1774 D.setInvalidType(); 1775 1776 // Just pretend that we didn't see the previous declaration. 1777 PrevDecl = 0; 1778 } 1779 1780 // In C++, the previous declaration we find might be a tag type 1781 // (class or enum). In this case, the new declaration will hide the 1782 // tag type. Note that this does does not apply if we're declaring a 1783 // typedef (C++ [dcl.typedef]p4). 1784 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1785 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1786 PrevDecl = 0; 1787 1788 bool Redeclaration = false; 1789 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1790 if (TemplateParamLists.size()) { 1791 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1792 return DeclPtrTy(); 1793 } 1794 1795 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1796 } else if (R->isFunctionType()) { 1797 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1798 move(TemplateParamLists), 1799 IsFunctionDefinition, Redeclaration); 1800 } else { 1801 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1802 move(TemplateParamLists), 1803 Redeclaration); 1804 } 1805 1806 if (New == 0) 1807 return DeclPtrTy(); 1808 1809 // If this has an identifier and is not an invalid redeclaration, 1810 // add it to the scope stack. 1811 if (Name && !(Redeclaration && New->isInvalidDecl())) 1812 PushOnScopeChains(New, S); 1813 1814 return DeclPtrTy::make(New); 1815} 1816 1817/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1818/// types into constant array types in certain situations which would otherwise 1819/// be errors (for GCC compatibility). 1820static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1821 ASTContext &Context, 1822 bool &SizeIsNegative) { 1823 // This method tries to turn a variable array into a constant 1824 // array even when the size isn't an ICE. This is necessary 1825 // for compatibility with code that depends on gcc's buggy 1826 // constant expression folding, like struct {char x[(int)(char*)2];} 1827 SizeIsNegative = false; 1828 1829 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1830 QualType Pointee = PTy->getPointeeType(); 1831 QualType FixedType = 1832 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1833 if (FixedType.isNull()) return FixedType; 1834 FixedType = Context.getPointerType(FixedType); 1835 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1836 return FixedType; 1837 } 1838 1839 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1840 if (!VLATy) 1841 return QualType(); 1842 // FIXME: We should probably handle this case 1843 if (VLATy->getElementType()->isVariablyModifiedType()) 1844 return QualType(); 1845 1846 Expr::EvalResult EvalResult; 1847 if (!VLATy->getSizeExpr() || 1848 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1849 !EvalResult.Val.isInt()) 1850 return QualType(); 1851 1852 llvm::APSInt &Res = EvalResult.Val.getInt(); 1853 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1854 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1855 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1856 // so as to transfer ownership to the ConstantArrayWithExpr. 1857 // Alternatively, we could "clone" it (how?). 1858 // Since we don't know how to do things above, we just use the 1859 // very same Expr*. 1860 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1861 Res, ArySizeExpr, 1862 ArrayType::Normal, 0, 1863 VLATy->getBracketsRange()); 1864 } 1865 1866 SizeIsNegative = true; 1867 return QualType(); 1868} 1869 1870/// \brief Register the given locally-scoped external C declaration so 1871/// that it can be found later for redeclarations 1872void 1873Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1874 Scope *S) { 1875 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1876 "Decl is not a locally-scoped decl!"); 1877 // Note that we have a locally-scoped external with this name. 1878 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1879 1880 if (!PrevDecl) 1881 return; 1882 1883 // If there was a previous declaration of this variable, it may be 1884 // in our identifier chain. Update the identifier chain with the new 1885 // declaration. 1886 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1887 // The previous declaration was found on the identifer resolver 1888 // chain, so remove it from its scope. 1889 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1890 S = S->getParent(); 1891 1892 if (S) 1893 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1894 } 1895} 1896 1897/// \brief Diagnose function specifiers on a declaration of an identifier that 1898/// does not identify a function. 1899void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1900 // FIXME: We should probably indicate the identifier in question to avoid 1901 // confusion for constructs like "inline int a(), b;" 1902 if (D.getDeclSpec().isInlineSpecified()) 1903 Diag(D.getDeclSpec().getInlineSpecLoc(), 1904 diag::err_inline_non_function); 1905 1906 if (D.getDeclSpec().isVirtualSpecified()) 1907 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1908 diag::err_virtual_non_function); 1909 1910 if (D.getDeclSpec().isExplicitSpecified()) 1911 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1912 diag::err_explicit_non_function); 1913} 1914 1915NamedDecl* 1916Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1917 QualType R, DeclaratorInfo *DInfo, 1918 Decl* PrevDecl, bool &Redeclaration) { 1919 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1920 if (D.getCXXScopeSpec().isSet()) { 1921 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1922 << D.getCXXScopeSpec().getRange(); 1923 D.setInvalidType(); 1924 // Pretend we didn't see the scope specifier. 1925 DC = 0; 1926 } 1927 1928 if (getLangOptions().CPlusPlus) { 1929 // Check that there are no default arguments (C++ only). 1930 CheckExtraCXXDefaultArguments(D); 1931 } 1932 1933 DiagnoseFunctionSpecifiers(D); 1934 1935 if (D.getDeclSpec().isThreadSpecified()) 1936 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1937 1938 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1939 if (!NewTD) return 0; 1940 1941 if (D.isInvalidType()) 1942 NewTD->setInvalidDecl(); 1943 1944 // Handle attributes prior to checking for duplicates in MergeVarDecl 1945 ProcessDeclAttributes(S, NewTD, D); 1946 // Merge the decl with the existing one if appropriate. If the decl is 1947 // in an outer scope, it isn't the same thing. 1948 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1949 Redeclaration = true; 1950 MergeTypeDefDecl(NewTD, PrevDecl); 1951 } 1952 1953 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1954 // then it shall have block scope. 1955 QualType T = NewTD->getUnderlyingType(); 1956 if (T->isVariablyModifiedType()) { 1957 CurFunctionNeedsScopeChecking = true; 1958 1959 if (S->getFnParent() == 0) { 1960 bool SizeIsNegative; 1961 QualType FixedTy = 1962 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1963 if (!FixedTy.isNull()) { 1964 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1965 NewTD->setUnderlyingType(FixedTy); 1966 } else { 1967 if (SizeIsNegative) 1968 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1969 else if (T->isVariableArrayType()) 1970 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1971 else 1972 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1973 NewTD->setInvalidDecl(); 1974 } 1975 } 1976 } 1977 1978 // If this is the C FILE type, notify the AST context. 1979 if (IdentifierInfo *II = NewTD->getIdentifier()) 1980 if (!NewTD->isInvalidDecl() && 1981 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 1982 if (II->isStr("FILE")) 1983 Context.setFILEDecl(NewTD); 1984 else if (II->isStr("jmp_buf")) 1985 Context.setjmp_bufDecl(NewTD); 1986 else if (II->isStr("sigjmp_buf")) 1987 Context.setsigjmp_bufDecl(NewTD); 1988 } 1989 1990 return NewTD; 1991} 1992 1993/// \brief Determines whether the given declaration is an out-of-scope 1994/// previous declaration. 1995/// 1996/// This routine should be invoked when name lookup has found a 1997/// previous declaration (PrevDecl) that is not in the scope where a 1998/// new declaration by the same name is being introduced. If the new 1999/// declaration occurs in a local scope, previous declarations with 2000/// linkage may still be considered previous declarations (C99 2001/// 6.2.2p4-5, C++ [basic.link]p6). 2002/// 2003/// \param PrevDecl the previous declaration found by name 2004/// lookup 2005/// 2006/// \param DC the context in which the new declaration is being 2007/// declared. 2008/// 2009/// \returns true if PrevDecl is an out-of-scope previous declaration 2010/// for a new delcaration with the same name. 2011static bool 2012isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2013 ASTContext &Context) { 2014 if (!PrevDecl) 2015 return 0; 2016 2017 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2018 // case we need to check each of the overloaded functions. 2019 if (!PrevDecl->hasLinkage()) 2020 return false; 2021 2022 if (Context.getLangOptions().CPlusPlus) { 2023 // C++ [basic.link]p6: 2024 // If there is a visible declaration of an entity with linkage 2025 // having the same name and type, ignoring entities declared 2026 // outside the innermost enclosing namespace scope, the block 2027 // scope declaration declares that same entity and receives the 2028 // linkage of the previous declaration. 2029 DeclContext *OuterContext = DC->getLookupContext(); 2030 if (!OuterContext->isFunctionOrMethod()) 2031 // This rule only applies to block-scope declarations. 2032 return false; 2033 else { 2034 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2035 if (PrevOuterContext->isRecord()) 2036 // We found a member function: ignore it. 2037 return false; 2038 else { 2039 // Find the innermost enclosing namespace for the new and 2040 // previous declarations. 2041 while (!OuterContext->isFileContext()) 2042 OuterContext = OuterContext->getParent(); 2043 while (!PrevOuterContext->isFileContext()) 2044 PrevOuterContext = PrevOuterContext->getParent(); 2045 2046 // The previous declaration is in a different namespace, so it 2047 // isn't the same function. 2048 if (OuterContext->getPrimaryContext() != 2049 PrevOuterContext->getPrimaryContext()) 2050 return false; 2051 } 2052 } 2053 } 2054 2055 return true; 2056} 2057 2058NamedDecl* 2059Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2060 QualType R, DeclaratorInfo *DInfo, 2061 NamedDecl* PrevDecl, 2062 MultiTemplateParamsArg TemplateParamLists, 2063 bool &Redeclaration) { 2064 DeclarationName Name = GetNameForDeclarator(D); 2065 2066 // Check that there are no default arguments (C++ only). 2067 if (getLangOptions().CPlusPlus) 2068 CheckExtraCXXDefaultArguments(D); 2069 2070 VarDecl *NewVD; 2071 VarDecl::StorageClass SC; 2072 switch (D.getDeclSpec().getStorageClassSpec()) { 2073 default: assert(0 && "Unknown storage class!"); 2074 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2075 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2076 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2077 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2078 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2079 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2080 case DeclSpec::SCS_mutable: 2081 // mutable can only appear on non-static class members, so it's always 2082 // an error here 2083 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2084 D.setInvalidType(); 2085 SC = VarDecl::None; 2086 break; 2087 } 2088 2089 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2090 if (!II) { 2091 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2092 << Name.getAsString(); 2093 return 0; 2094 } 2095 2096 DiagnoseFunctionSpecifiers(D); 2097 2098 if (!DC->isRecord() && S->getFnParent() == 0) { 2099 // C99 6.9p2: The storage-class specifiers auto and register shall not 2100 // appear in the declaration specifiers in an external declaration. 2101 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2102 2103 // If this is a register variable with an asm label specified, then this 2104 // is a GNU extension. 2105 if (SC == VarDecl::Register && D.getAsmLabel()) 2106 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2107 else 2108 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2109 D.setInvalidType(); 2110 } 2111 } 2112 if (DC->isRecord() && !CurContext->isRecord()) { 2113 // This is an out-of-line definition of a static data member. 2114 if (SC == VarDecl::Static) { 2115 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2116 diag::err_static_out_of_line) 2117 << CodeModificationHint::CreateRemoval( 2118 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2119 } else if (SC == VarDecl::None) 2120 SC = VarDecl::Static; 2121 } 2122 if (SC == VarDecl::Static) { 2123 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2124 if (RD->isLocalClass()) 2125 Diag(D.getIdentifierLoc(), 2126 diag::err_static_data_member_not_allowed_in_local_class) 2127 << Name << RD->getDeclName(); 2128 } 2129 } 2130 2131 // Match up the template parameter lists with the scope specifier, then 2132 // determine whether we have a template or a template specialization. 2133 if (TemplateParameterList *TemplateParams 2134 = MatchTemplateParametersToScopeSpecifier( 2135 D.getDeclSpec().getSourceRange().getBegin(), 2136 D.getCXXScopeSpec(), 2137 (TemplateParameterList**)TemplateParamLists.get(), 2138 TemplateParamLists.size())) { 2139 if (TemplateParams->size() > 0) { 2140 // There is no such thing as a variable template. 2141 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2142 << II 2143 << SourceRange(TemplateParams->getTemplateLoc(), 2144 TemplateParams->getRAngleLoc()); 2145 return 0; 2146 } else { 2147 // There is an extraneous 'template<>' for this variable. Complain 2148 // about it, but allow the declaration of the variable. 2149 Diag(TemplateParams->getTemplateLoc(), 2150 diag::err_template_variable_noparams) 2151 << II 2152 << SourceRange(TemplateParams->getTemplateLoc(), 2153 TemplateParams->getRAngleLoc()); 2154 } 2155 } 2156 2157 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2158 II, R, DInfo, SC); 2159 2160 if (D.isInvalidType()) 2161 NewVD->setInvalidDecl(); 2162 2163 if (D.getDeclSpec().isThreadSpecified()) { 2164 if (NewVD->hasLocalStorage()) 2165 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2166 else if (!Context.Target.isTLSSupported()) 2167 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2168 else 2169 NewVD->setThreadSpecified(true); 2170 } 2171 2172 // Set the lexical context. If the declarator has a C++ scope specifier, the 2173 // lexical context will be different from the semantic context. 2174 NewVD->setLexicalDeclContext(CurContext); 2175 2176 // Handle attributes prior to checking for duplicates in MergeVarDecl 2177 ProcessDeclAttributes(S, NewVD, D); 2178 2179 // Handle GNU asm-label extension (encoded as an attribute). 2180 if (Expr *E = (Expr*) D.getAsmLabel()) { 2181 // The parser guarantees this is a string. 2182 StringLiteral *SE = cast<StringLiteral>(E); 2183 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2184 SE->getByteLength()))); 2185 } 2186 2187 // If name lookup finds a previous declaration that is not in the 2188 // same scope as the new declaration, this may still be an 2189 // acceptable redeclaration. 2190 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2191 !(NewVD->hasLinkage() && 2192 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2193 PrevDecl = 0; 2194 2195 // Merge the decl with the existing one if appropriate. 2196 if (PrevDecl) { 2197 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2198 // The user tried to define a non-static data member 2199 // out-of-line (C++ [dcl.meaning]p1). 2200 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2201 << D.getCXXScopeSpec().getRange(); 2202 PrevDecl = 0; 2203 NewVD->setInvalidDecl(); 2204 } 2205 } else if (D.getCXXScopeSpec().isSet()) { 2206 // No previous declaration in the qualifying scope. 2207 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 2208 << Name << D.getCXXScopeSpec().getRange(); 2209 NewVD->setInvalidDecl(); 2210 } 2211 2212 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2213 2214 // attributes declared post-definition are currently ignored 2215 if (PrevDecl) { 2216 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2217 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2218 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2219 Diag(Def->getLocation(), diag::note_previous_definition); 2220 } 2221 } 2222 2223 // If this is a locally-scoped extern C variable, update the map of 2224 // such variables. 2225 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2226 !NewVD->isInvalidDecl()) 2227 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2228 2229 return NewVD; 2230} 2231 2232/// \brief Perform semantic checking on a newly-created variable 2233/// declaration. 2234/// 2235/// This routine performs all of the type-checking required for a 2236/// variable declaration once it has been built. It is used both to 2237/// check variables after they have been parsed and their declarators 2238/// have been translated into a declaration, and to check variables 2239/// that have been instantiated from a template. 2240/// 2241/// Sets NewVD->isInvalidDecl() if an error was encountered. 2242void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2243 bool &Redeclaration) { 2244 // If the decl is already known invalid, don't check it. 2245 if (NewVD->isInvalidDecl()) 2246 return; 2247 2248 QualType T = NewVD->getType(); 2249 2250 if (T->isObjCInterfaceType()) { 2251 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2252 return NewVD->setInvalidDecl(); 2253 } 2254 2255 // The variable can not have an abstract class type. 2256 if (RequireNonAbstractType(NewVD->getLocation(), T, 2257 diag::err_abstract_type_in_decl, 2258 AbstractVariableType)) 2259 return NewVD->setInvalidDecl(); 2260 2261 // Emit an error if an address space was applied to decl with local storage. 2262 // This includes arrays of objects with address space qualifiers, but not 2263 // automatic variables that point to other address spaces. 2264 // ISO/IEC TR 18037 S5.1.2 2265 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2266 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2267 return NewVD->setInvalidDecl(); 2268 } 2269 2270 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2271 && !NewVD->hasAttr<BlocksAttr>()) 2272 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2273 2274 bool isVM = T->isVariablyModifiedType(); 2275 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2276 NewVD->hasAttr<BlocksAttr>()) 2277 CurFunctionNeedsScopeChecking = true; 2278 2279 if ((isVM && NewVD->hasLinkage()) || 2280 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2281 bool SizeIsNegative; 2282 QualType FixedTy = 2283 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2284 2285 if (FixedTy.isNull() && T->isVariableArrayType()) { 2286 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2287 // FIXME: This won't give the correct result for 2288 // int a[10][n]; 2289 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2290 2291 if (NewVD->isFileVarDecl()) 2292 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2293 << SizeRange; 2294 else if (NewVD->getStorageClass() == VarDecl::Static) 2295 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2296 << SizeRange; 2297 else 2298 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2299 << SizeRange; 2300 return NewVD->setInvalidDecl(); 2301 } 2302 2303 if (FixedTy.isNull()) { 2304 if (NewVD->isFileVarDecl()) 2305 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2306 else 2307 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2308 return NewVD->setInvalidDecl(); 2309 } 2310 2311 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2312 NewVD->setType(FixedTy); 2313 } 2314 2315 if (!PrevDecl && NewVD->isExternC(Context)) { 2316 // Since we did not find anything by this name and we're declaring 2317 // an extern "C" variable, look for a non-visible extern "C" 2318 // declaration with the same name. 2319 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2320 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2321 if (Pos != LocallyScopedExternalDecls.end()) 2322 PrevDecl = Pos->second; 2323 } 2324 2325 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2326 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2327 << T; 2328 return NewVD->setInvalidDecl(); 2329 } 2330 2331 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2332 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2333 return NewVD->setInvalidDecl(); 2334 } 2335 2336 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2337 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2338 return NewVD->setInvalidDecl(); 2339 } 2340 2341 if (PrevDecl) { 2342 Redeclaration = true; 2343 MergeVarDecl(NewVD, PrevDecl); 2344 } 2345} 2346 2347NamedDecl* 2348Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2349 QualType R, DeclaratorInfo *DInfo, 2350 NamedDecl* PrevDecl, 2351 MultiTemplateParamsArg TemplateParamLists, 2352 bool IsFunctionDefinition, bool &Redeclaration) { 2353 assert(R.getTypePtr()->isFunctionType()); 2354 2355 DeclarationName Name = GetNameForDeclarator(D); 2356 FunctionDecl::StorageClass SC = FunctionDecl::None; 2357 switch (D.getDeclSpec().getStorageClassSpec()) { 2358 default: assert(0 && "Unknown storage class!"); 2359 case DeclSpec::SCS_auto: 2360 case DeclSpec::SCS_register: 2361 case DeclSpec::SCS_mutable: 2362 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2363 diag::err_typecheck_sclass_func); 2364 D.setInvalidType(); 2365 break; 2366 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2367 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2368 case DeclSpec::SCS_static: { 2369 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2370 // C99 6.7.1p5: 2371 // The declaration of an identifier for a function that has 2372 // block scope shall have no explicit storage-class specifier 2373 // other than extern 2374 // See also (C++ [dcl.stc]p4). 2375 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2376 diag::err_static_block_func); 2377 SC = FunctionDecl::None; 2378 } else 2379 SC = FunctionDecl::Static; 2380 break; 2381 } 2382 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2383 } 2384 2385 if (D.getDeclSpec().isThreadSpecified()) 2386 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2387 2388 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2389 bool isInline = D.getDeclSpec().isInlineSpecified(); 2390 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2391 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2392 2393 // Check that the return type is not an abstract class type. 2394 // For record types, this is done by the AbstractClassUsageDiagnoser once 2395 // the class has been completely parsed. 2396 if (!DC->isRecord() && 2397 RequireNonAbstractType(D.getIdentifierLoc(), 2398 R->getAsFunctionType()->getResultType(), 2399 diag::err_abstract_type_in_decl, 2400 AbstractReturnType)) 2401 D.setInvalidType(); 2402 2403 // Do not allow returning a objc interface by-value. 2404 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2405 Diag(D.getIdentifierLoc(), 2406 diag::err_object_cannot_be_passed_returned_by_value) << 0 2407 << R->getAsFunctionType()->getResultType(); 2408 D.setInvalidType(); 2409 } 2410 2411 bool isVirtualOkay = false; 2412 FunctionDecl *NewFD; 2413 if (isFriend) { 2414 // DC is the namespace in which the function is being declared. 2415 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2416 "friend function being created in a non-namespace context"); 2417 2418 // C++ [class.friend]p5 2419 // A function can be defined in a friend declaration of a 2420 // class . . . . Such a function is implicitly inline. 2421 isInline |= IsFunctionDefinition; 2422 2423 NewFD = FriendFunctionDecl::Create(Context, DC, 2424 D.getIdentifierLoc(), Name, R, DInfo, 2425 isInline, 2426 D.getDeclSpec().getFriendSpecLoc()); 2427 2428 } else if (D.getKind() == Declarator::DK_Constructor) { 2429 // This is a C++ constructor declaration. 2430 assert(DC->isRecord() && 2431 "Constructors can only be declared in a member context"); 2432 2433 R = CheckConstructorDeclarator(D, R, SC); 2434 2435 // Create the new declaration 2436 NewFD = CXXConstructorDecl::Create(Context, 2437 cast<CXXRecordDecl>(DC), 2438 D.getIdentifierLoc(), Name, R, DInfo, 2439 isExplicit, isInline, 2440 /*isImplicitlyDeclared=*/false); 2441 } else if (D.getKind() == Declarator::DK_Destructor) { 2442 // This is a C++ destructor declaration. 2443 if (DC->isRecord()) { 2444 R = CheckDestructorDeclarator(D, SC); 2445 2446 NewFD = CXXDestructorDecl::Create(Context, 2447 cast<CXXRecordDecl>(DC), 2448 D.getIdentifierLoc(), Name, R, 2449 isInline, 2450 /*isImplicitlyDeclared=*/false); 2451 2452 isVirtualOkay = true; 2453 } else { 2454 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2455 2456 // Create a FunctionDecl to satisfy the function definition parsing 2457 // code path. 2458 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2459 Name, R, DInfo, SC, isInline, 2460 /*hasPrototype=*/true); 2461 D.setInvalidType(); 2462 } 2463 } else if (D.getKind() == Declarator::DK_Conversion) { 2464 if (!DC->isRecord()) { 2465 Diag(D.getIdentifierLoc(), 2466 diag::err_conv_function_not_member); 2467 return 0; 2468 } 2469 2470 CheckConversionDeclarator(D, R, SC); 2471 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2472 D.getIdentifierLoc(), Name, R, DInfo, 2473 isInline, isExplicit); 2474 2475 isVirtualOkay = true; 2476 } else if (DC->isRecord()) { 2477 // If the of the function is the same as the name of the record, then this 2478 // must be an invalid constructor that has a return type. 2479 // (The parser checks for a return type and makes the declarator a 2480 // constructor if it has no return type). 2481 // must have an invalid constructor that has a return type 2482 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2483 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2484 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2485 << SourceRange(D.getIdentifierLoc()); 2486 return 0; 2487 } 2488 2489 // This is a C++ method declaration. 2490 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2491 D.getIdentifierLoc(), Name, R, DInfo, 2492 (SC == FunctionDecl::Static), isInline); 2493 2494 isVirtualOkay = (SC != FunctionDecl::Static); 2495 } else { 2496 // Determine whether the function was written with a 2497 // prototype. This true when: 2498 // - we're in C++ (where every function has a prototype), 2499 // - there is a prototype in the declarator, or 2500 // - the type R of the function is some kind of typedef or other reference 2501 // to a type name (which eventually refers to a function type). 2502 bool HasPrototype = 2503 getLangOptions().CPlusPlus || 2504 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2505 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2506 2507 NewFD = FunctionDecl::Create(Context, DC, 2508 D.getIdentifierLoc(), 2509 Name, R, DInfo, SC, isInline, HasPrototype); 2510 } 2511 2512 if (D.isInvalidType()) 2513 NewFD->setInvalidDecl(); 2514 2515 // Set the lexical context. If the declarator has a C++ 2516 // scope specifier, the lexical context will be different 2517 // from the semantic context. 2518 NewFD->setLexicalDeclContext(CurContext); 2519 2520 // Match up the template parameter lists with the scope specifier, then 2521 // determine whether we have a template or a template specialization. 2522 FunctionTemplateDecl *FunctionTemplate = 0; 2523 if (TemplateParameterList *TemplateParams 2524 = MatchTemplateParametersToScopeSpecifier( 2525 D.getDeclSpec().getSourceRange().getBegin(), 2526 D.getCXXScopeSpec(), 2527 (TemplateParameterList**)TemplateParamLists.get(), 2528 TemplateParamLists.size())) { 2529 if (TemplateParams->size() > 0) { 2530 // This is a function template 2531 2532 // Check that we can declare a template here. 2533 if (CheckTemplateDeclScope(S, TemplateParams)) 2534 return 0; 2535 2536 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2537 NewFD->getLocation(), 2538 Name, TemplateParams, 2539 NewFD); 2540 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2541 } else { 2542 // FIXME: Handle function template specializations 2543 } 2544 2545 // FIXME: Free this memory properly. 2546 TemplateParamLists.release(); 2547 } 2548 2549 // C++ [dcl.fct.spec]p5: 2550 // The virtual specifier shall only be used in declarations of 2551 // nonstatic class member functions that appear within a 2552 // member-specification of a class declaration; see 10.3. 2553 // 2554 if (isVirtual && !NewFD->isInvalidDecl()) { 2555 if (!isVirtualOkay) { 2556 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2557 diag::err_virtual_non_function); 2558 } else if (!CurContext->isRecord()) { 2559 // 'virtual' was specified outside of the class. 2560 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2561 << CodeModificationHint::CreateRemoval( 2562 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2563 } else { 2564 // Okay: Add virtual to the method. 2565 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2566 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2567 CurClass->setAggregate(false); 2568 CurClass->setPOD(false); 2569 CurClass->setEmpty(false); 2570 CurClass->setPolymorphic(true); 2571 CurClass->setHasTrivialConstructor(false); 2572 CurClass->setHasTrivialCopyConstructor(false); 2573 CurClass->setHasTrivialCopyAssignment(false); 2574 } 2575 } 2576 2577 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2578 // Look for virtual methods in base classes that this method might override. 2579 2580 BasePaths Paths; 2581 if (LookupInBases(cast<CXXRecordDecl>(DC), 2582 MemberLookupCriteria(NewMD), Paths)) { 2583 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2584 E = Paths.found_decls_end(); I != E; ++I) { 2585 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2586 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2587 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2588 NewMD->addOverriddenMethod(OldMD); 2589 } 2590 } 2591 } 2592 } 2593 2594 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2595 !CurContext->isRecord()) { 2596 // C++ [class.static]p1: 2597 // A data or function member of a class may be declared static 2598 // in a class definition, in which case it is a static member of 2599 // the class. 2600 2601 // Complain about the 'static' specifier if it's on an out-of-line 2602 // member function definition. 2603 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2604 diag::err_static_out_of_line) 2605 << CodeModificationHint::CreateRemoval( 2606 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2607 } 2608 2609 // Handle GNU asm-label extension (encoded as an attribute). 2610 if (Expr *E = (Expr*) D.getAsmLabel()) { 2611 // The parser guarantees this is a string. 2612 StringLiteral *SE = cast<StringLiteral>(E); 2613 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2614 SE->getByteLength()))); 2615 } 2616 2617 // Copy the parameter declarations from the declarator D to the function 2618 // declaration NewFD, if they are available. First scavenge them into Params. 2619 llvm::SmallVector<ParmVarDecl*, 16> Params; 2620 if (D.getNumTypeObjects() > 0) { 2621 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2622 2623 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2624 // function that takes no arguments, not a function that takes a 2625 // single void argument. 2626 // We let through "const void" here because Sema::GetTypeForDeclarator 2627 // already checks for that case. 2628 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2629 FTI.ArgInfo[0].Param && 2630 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2631 // Empty arg list, don't push any params. 2632 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2633 2634 // In C++, the empty parameter-type-list must be spelled "void"; a 2635 // typedef of void is not permitted. 2636 if (getLangOptions().CPlusPlus && 2637 Param->getType().getUnqualifiedType() != Context.VoidTy) 2638 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2639 // FIXME: Leaks decl? 2640 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2641 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2642 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2643 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2644 Param->setDeclContext(NewFD); 2645 Params.push_back(Param); 2646 } 2647 } 2648 2649 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2650 // When we're declaring a function with a typedef, typeof, etc as in the 2651 // following example, we'll need to synthesize (unnamed) 2652 // parameters for use in the declaration. 2653 // 2654 // @code 2655 // typedef void fn(int); 2656 // fn f; 2657 // @endcode 2658 2659 // Synthesize a parameter for each argument type. 2660 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2661 AE = FT->arg_type_end(); AI != AE; ++AI) { 2662 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2663 SourceLocation(), 0, 2664 *AI, /*DInfo=*/0, 2665 VarDecl::None, 0); 2666 Param->setImplicit(); 2667 Params.push_back(Param); 2668 } 2669 } else { 2670 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2671 "Should not need args for typedef of non-prototype fn"); 2672 } 2673 // Finally, we know we have the right number of parameters, install them. 2674 NewFD->setParams(Context, Params.data(), Params.size()); 2675 2676 // If name lookup finds a previous declaration that is not in the 2677 // same scope as the new declaration, this may still be an 2678 // acceptable redeclaration. 2679 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2680 !(NewFD->hasLinkage() && 2681 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2682 PrevDecl = 0; 2683 2684 // Perform semantic checking on the function declaration. 2685 bool OverloadableAttrRequired = false; // FIXME: HACK! 2686 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2687 /*FIXME:*/OverloadableAttrRequired); 2688 2689 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2690 // An out-of-line member function declaration must also be a 2691 // definition (C++ [dcl.meaning]p1). 2692 if (!IsFunctionDefinition && !isFriend) { 2693 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2694 << D.getCXXScopeSpec().getRange(); 2695 NewFD->setInvalidDecl(); 2696 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2697 // The user tried to provide an out-of-line definition for a 2698 // function that is a member of a class or namespace, but there 2699 // was no such member function declared (C++ [class.mfct]p2, 2700 // C++ [namespace.memdef]p2). For example: 2701 // 2702 // class X { 2703 // void f() const; 2704 // }; 2705 // 2706 // void X::f() { } // ill-formed 2707 // 2708 // Complain about this problem, and attempt to suggest close 2709 // matches (e.g., those that differ only in cv-qualifiers and 2710 // whether the parameter types are references). 2711 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2712 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2713 NewFD->setInvalidDecl(); 2714 2715 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2716 true); 2717 assert(!Prev.isAmbiguous() && 2718 "Cannot have an ambiguity in previous-declaration lookup"); 2719 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2720 Func != FuncEnd; ++Func) { 2721 if (isa<FunctionDecl>(*Func) && 2722 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2723 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2724 } 2725 2726 PrevDecl = 0; 2727 } 2728 } 2729 2730 // Handle attributes. We need to have merged decls when handling attributes 2731 // (for example to check for conflicts, etc). 2732 // FIXME: This needs to happen before we merge declarations. Then, 2733 // let attribute merging cope with attribute conflicts. 2734 ProcessDeclAttributes(S, NewFD, D); 2735 2736 // attributes declared post-definition are currently ignored 2737 if (PrevDecl) { 2738 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2739 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2740 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2741 Diag(Def->getLocation(), diag::note_previous_definition); 2742 } 2743 } 2744 2745 AddKnownFunctionAttributes(NewFD); 2746 2747 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2748 // If a function name is overloadable in C, then every function 2749 // with that name must be marked "overloadable". 2750 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2751 << Redeclaration << NewFD; 2752 if (PrevDecl) 2753 Diag(PrevDecl->getLocation(), 2754 diag::note_attribute_overloadable_prev_overload); 2755 NewFD->addAttr(::new (Context) OverloadableAttr()); 2756 } 2757 2758 // If this is a locally-scoped extern C function, update the 2759 // map of such names. 2760 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2761 && !NewFD->isInvalidDecl()) 2762 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2763 2764 // Set this FunctionDecl's range up to the right paren. 2765 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2766 2767 if (FunctionTemplate && NewFD->isInvalidDecl()) 2768 FunctionTemplate->setInvalidDecl(); 2769 2770 if (FunctionTemplate) 2771 return FunctionTemplate; 2772 2773 return NewFD; 2774} 2775 2776/// \brief Perform semantic checking of a new function declaration. 2777/// 2778/// Performs semantic analysis of the new function declaration 2779/// NewFD. This routine performs all semantic checking that does not 2780/// require the actual declarator involved in the declaration, and is 2781/// used both for the declaration of functions as they are parsed 2782/// (called via ActOnDeclarator) and for the declaration of functions 2783/// that have been instantiated via C++ template instantiation (called 2784/// via InstantiateDecl). 2785/// 2786/// This sets NewFD->isInvalidDecl() to true if there was an error. 2787void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2788 bool &Redeclaration, 2789 bool &OverloadableAttrRequired) { 2790 // If NewFD is already known erroneous, don't do any of this checking. 2791 if (NewFD->isInvalidDecl()) 2792 return; 2793 2794 if (NewFD->getResultType()->isVariablyModifiedType()) { 2795 // Functions returning a variably modified type violate C99 6.7.5.2p2 2796 // because all functions have linkage. 2797 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2798 return NewFD->setInvalidDecl(); 2799 } 2800 2801 if (NewFD->isMain(Context)) CheckMain(NewFD); 2802 2803 // Semantic checking for this function declaration (in isolation). 2804 if (getLangOptions().CPlusPlus) { 2805 // C++-specific checks. 2806 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2807 CheckConstructor(Constructor); 2808 } else if (isa<CXXDestructorDecl>(NewFD)) { 2809 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2810 QualType ClassType = Context.getTypeDeclType(Record); 2811 if (!ClassType->isDependentType()) { 2812 DeclarationName Name 2813 = Context.DeclarationNames.getCXXDestructorName( 2814 Context.getCanonicalType(ClassType)); 2815 if (NewFD->getDeclName() != Name) { 2816 Diag(NewFD->getLocation(), diag::err_destructor_name); 2817 return NewFD->setInvalidDecl(); 2818 } 2819 } 2820 Record->setUserDeclaredDestructor(true); 2821 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2822 // user-defined destructor. 2823 Record->setPOD(false); 2824 2825 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2826 // declared destructor. 2827 // FIXME: C++0x: don't do this for "= default" destructors 2828 Record->setHasTrivialDestructor(false); 2829 } else if (CXXConversionDecl *Conversion 2830 = dyn_cast<CXXConversionDecl>(NewFD)) 2831 ActOnConversionDeclarator(Conversion); 2832 2833 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2834 if (NewFD->isOverloadedOperator() && 2835 CheckOverloadedOperatorDeclaration(NewFD)) 2836 return NewFD->setInvalidDecl(); 2837 } 2838 2839 // C99 6.7.4p6: 2840 // [... ] For a function with external linkage, the following 2841 // restrictions apply: [...] If all of the file scope declarations 2842 // for a function in a translation unit include the inline 2843 // function specifier without extern, then the definition in that 2844 // translation unit is an inline definition. An inline definition 2845 // does not provide an external definition for the function, and 2846 // does not forbid an external definition in another translation 2847 // unit. 2848 // 2849 // Here we determine whether this function, in isolation, would be a 2850 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2851 // previous declarations. 2852 if (NewFD->isInline() && getLangOptions().C99 && 2853 NewFD->getStorageClass() == FunctionDecl::None && 2854 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2855 NewFD->setC99InlineDefinition(true); 2856 2857 // Check for a previous declaration of this name. 2858 if (!PrevDecl && NewFD->isExternC(Context)) { 2859 // Since we did not find anything by this name and we're declaring 2860 // an extern "C" function, look for a non-visible extern "C" 2861 // declaration with the same name. 2862 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2863 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2864 if (Pos != LocallyScopedExternalDecls.end()) 2865 PrevDecl = Pos->second; 2866 } 2867 2868 // Merge or overload the declaration with an existing declaration of 2869 // the same name, if appropriate. 2870 if (PrevDecl) { 2871 // Determine whether NewFD is an overload of PrevDecl or 2872 // a declaration that requires merging. If it's an overload, 2873 // there's no more work to do here; we'll just add the new 2874 // function to the scope. 2875 OverloadedFunctionDecl::function_iterator MatchedDecl; 2876 2877 if (!getLangOptions().CPlusPlus && 2878 AllowOverloadingOfFunction(PrevDecl, Context)) { 2879 OverloadableAttrRequired = true; 2880 2881 // Functions marked "overloadable" must have a prototype (that 2882 // we can't get through declaration merging). 2883 if (!NewFD->getType()->getAsFunctionProtoType()) { 2884 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2885 << NewFD; 2886 Redeclaration = true; 2887 2888 // Turn this into a variadic function with no parameters. 2889 QualType R = Context.getFunctionType( 2890 NewFD->getType()->getAsFunctionType()->getResultType(), 2891 0, 0, true, 0); 2892 NewFD->setType(R); 2893 return NewFD->setInvalidDecl(); 2894 } 2895 } 2896 2897 if (PrevDecl && 2898 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2899 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2900 !isa<UsingDecl>(PrevDecl)) { 2901 Redeclaration = true; 2902 Decl *OldDecl = PrevDecl; 2903 2904 // If PrevDecl was an overloaded function, extract the 2905 // FunctionDecl that matched. 2906 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2907 OldDecl = *MatchedDecl; 2908 2909 // NewFD and OldDecl represent declarations that need to be 2910 // merged. 2911 if (MergeFunctionDecl(NewFD, OldDecl)) 2912 return NewFD->setInvalidDecl(); 2913 2914 if (FunctionTemplateDecl *OldTemplateDecl 2915 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2916 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2917 else { 2918 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2919 NewFD->setAccess(OldDecl->getAccess()); 2920 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2921 } 2922 } 2923 } 2924 2925 // In C++, check default arguments now that we have merged decls. Unless 2926 // the lexical context is the class, because in this case this is done 2927 // during delayed parsing anyway. 2928 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2929 CheckCXXDefaultArguments(NewFD); 2930} 2931 2932void Sema::CheckMain(FunctionDecl* FD) { 2933 // C++ [basic.start.main]p3: A program that declares main to be inline 2934 // or static is ill-formed. 2935 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2936 // shall not appear in a declaration of main. 2937 // static main is not an error under C99, but we should warn about it. 2938 bool isInline = FD->isInline(); 2939 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2940 if (isInline || isStatic) { 2941 unsigned diagID = diag::warn_unusual_main_decl; 2942 if (isInline || getLangOptions().CPlusPlus) 2943 diagID = diag::err_unusual_main_decl; 2944 2945 int which = isStatic + (isInline << 1) - 1; 2946 Diag(FD->getLocation(), diagID) << which; 2947 } 2948 2949 QualType T = FD->getType(); 2950 assert(T->isFunctionType() && "function decl is not of function type"); 2951 const FunctionType* FT = T->getAsFunctionType(); 2952 2953 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2954 // TODO: add a replacement fixit to turn the return type into 'int'. 2955 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2956 FD->setInvalidDecl(true); 2957 } 2958 2959 // Treat protoless main() as nullary. 2960 if (isa<FunctionNoProtoType>(FT)) return; 2961 2962 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2963 unsigned nparams = FTP->getNumArgs(); 2964 assert(FD->getNumParams() == nparams); 2965 2966 if (nparams > 3) { 2967 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2968 FD->setInvalidDecl(true); 2969 nparams = 3; 2970 } 2971 2972 // FIXME: a lot of the following diagnostics would be improved 2973 // if we had some location information about types. 2974 2975 QualType CharPP = 2976 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2977 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2978 2979 for (unsigned i = 0; i < nparams; ++i) { 2980 QualType AT = FTP->getArgType(i); 2981 2982 bool mismatch = true; 2983 2984 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2985 mismatch = false; 2986 else if (Expected[i] == CharPP) { 2987 // As an extension, the following forms are okay: 2988 // char const ** 2989 // char const * const * 2990 // char * const * 2991 2992 QualifierSet qs; 2993 const PointerType* PT; 2994 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 2995 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 2996 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2997 qs.removeConst(); 2998 mismatch = !qs.empty(); 2999 } 3000 } 3001 3002 if (mismatch) { 3003 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3004 // TODO: suggest replacing given type with expected type 3005 FD->setInvalidDecl(true); 3006 } 3007 } 3008 3009 if (nparams == 1 && !FD->isInvalidDecl()) { 3010 Diag(FD->getLocation(), diag::warn_main_one_arg); 3011 } 3012} 3013 3014bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3015 // FIXME: Need strict checking. In C89, we need to check for 3016 // any assignment, increment, decrement, function-calls, or 3017 // commas outside of a sizeof. In C99, it's the same list, 3018 // except that the aforementioned are allowed in unevaluated 3019 // expressions. Everything else falls under the 3020 // "may accept other forms of constant expressions" exception. 3021 // (We never end up here for C++, so the constant expression 3022 // rules there don't matter.) 3023 if (Init->isConstantInitializer(Context)) 3024 return false; 3025 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3026 << Init->getSourceRange(); 3027 return true; 3028} 3029 3030void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3031 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3032} 3033 3034/// AddInitializerToDecl - Adds the initializer Init to the 3035/// declaration dcl. If DirectInit is true, this is C++ direct 3036/// initialization rather than copy initialization. 3037void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3038 Decl *RealDecl = dcl.getAs<Decl>(); 3039 // If there is no declaration, there was an error parsing it. Just ignore 3040 // the initializer. 3041 if (RealDecl == 0) 3042 return; 3043 3044 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3045 // With declarators parsed the way they are, the parser cannot 3046 // distinguish between a normal initializer and a pure-specifier. 3047 // Thus this grotesque test. 3048 IntegerLiteral *IL; 3049 Expr *Init = static_cast<Expr *>(init.get()); 3050 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3051 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3052 if (Method->isVirtualAsWritten()) { 3053 Method->setPure(); 3054 3055 // A class is abstract if at least one function is pure virtual. 3056 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3057 } else if (!Method->isInvalidDecl()) { 3058 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3059 << Method->getDeclName() << Init->getSourceRange(); 3060 Method->setInvalidDecl(); 3061 } 3062 } else { 3063 Diag(Method->getLocation(), diag::err_member_function_initialization) 3064 << Method->getDeclName() << Init->getSourceRange(); 3065 Method->setInvalidDecl(); 3066 } 3067 return; 3068 } 3069 3070 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3071 if (!VDecl) { 3072 if (getLangOptions().CPlusPlus && 3073 RealDecl->getLexicalDeclContext()->isRecord() && 3074 isa<NamedDecl>(RealDecl)) 3075 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3076 << cast<NamedDecl>(RealDecl)->getDeclName(); 3077 else 3078 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3079 RealDecl->setInvalidDecl(); 3080 return; 3081 } 3082 3083 if (!VDecl->getType()->isArrayType() && 3084 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3085 diag::err_typecheck_decl_incomplete_type)) { 3086 RealDecl->setInvalidDecl(); 3087 return; 3088 } 3089 3090 const VarDecl *Def = 0; 3091 if (VDecl->getDefinition(Def)) { 3092 Diag(VDecl->getLocation(), diag::err_redefinition) 3093 << VDecl->getDeclName(); 3094 Diag(Def->getLocation(), diag::note_previous_definition); 3095 VDecl->setInvalidDecl(); 3096 return; 3097 } 3098 3099 // Take ownership of the expression, now that we're sure we have somewhere 3100 // to put it. 3101 Expr *Init = init.takeAs<Expr>(); 3102 assert(Init && "missing initializer"); 3103 3104 // Get the decls type and save a reference for later, since 3105 // CheckInitializerTypes may change it. 3106 QualType DclT = VDecl->getType(), SavT = DclT; 3107 if (VDecl->isBlockVarDecl()) { 3108 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3109 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3110 VDecl->setInvalidDecl(); 3111 } else if (!VDecl->isInvalidDecl()) { 3112 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3113 VDecl->getDeclName(), DirectInit)) 3114 VDecl->setInvalidDecl(); 3115 3116 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3117 // Don't check invalid declarations to avoid emitting useless diagnostics. 3118 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3119 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3120 CheckForConstantInitializer(Init, DclT); 3121 } 3122 } 3123 } else if (VDecl->isStaticDataMember() && 3124 VDecl->getLexicalDeclContext()->isRecord()) { 3125 // This is an in-class initialization for a static data member, e.g., 3126 // 3127 // struct S { 3128 // static const int value = 17; 3129 // }; 3130 3131 // Attach the initializer 3132 VDecl->setInit(Context, Init); 3133 3134 // C++ [class.mem]p4: 3135 // A member-declarator can contain a constant-initializer only 3136 // if it declares a static member (9.4) of const integral or 3137 // const enumeration type, see 9.4.2. 3138 QualType T = VDecl->getType(); 3139 if (!T->isDependentType() && 3140 (!Context.getCanonicalType(T).isConstQualified() || 3141 !T->isIntegralType())) { 3142 Diag(VDecl->getLocation(), diag::err_member_initialization) 3143 << VDecl->getDeclName() << Init->getSourceRange(); 3144 VDecl->setInvalidDecl(); 3145 } else { 3146 // C++ [class.static.data]p4: 3147 // If a static data member is of const integral or const 3148 // enumeration type, its declaration in the class definition 3149 // can specify a constant-initializer which shall be an 3150 // integral constant expression (5.19). 3151 if (!Init->isTypeDependent() && 3152 !Init->getType()->isIntegralType()) { 3153 // We have a non-dependent, non-integral or enumeration type. 3154 Diag(Init->getSourceRange().getBegin(), 3155 diag::err_in_class_initializer_non_integral_type) 3156 << Init->getType() << Init->getSourceRange(); 3157 VDecl->setInvalidDecl(); 3158 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3159 // Check whether the expression is a constant expression. 3160 llvm::APSInt Value; 3161 SourceLocation Loc; 3162 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3163 Diag(Loc, diag::err_in_class_initializer_non_constant) 3164 << Init->getSourceRange(); 3165 VDecl->setInvalidDecl(); 3166 } else if (!VDecl->getType()->isDependentType()) 3167 ImpCastExprToType(Init, VDecl->getType()); 3168 } 3169 } 3170 } else if (VDecl->isFileVarDecl()) { 3171 if (VDecl->getStorageClass() == VarDecl::Extern) 3172 Diag(VDecl->getLocation(), diag::warn_extern_init); 3173 if (!VDecl->isInvalidDecl()) 3174 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3175 VDecl->getDeclName(), DirectInit)) 3176 VDecl->setInvalidDecl(); 3177 3178 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3179 // Don't check invalid declarations to avoid emitting useless diagnostics. 3180 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3181 // C99 6.7.8p4. All file scoped initializers need to be constant. 3182 CheckForConstantInitializer(Init, DclT); 3183 } 3184 } 3185 // If the type changed, it means we had an incomplete type that was 3186 // completed by the initializer. For example: 3187 // int ary[] = { 1, 3, 5 }; 3188 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3189 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3190 VDecl->setType(DclT); 3191 Init->setType(DclT); 3192 } 3193 3194 Init = MaybeCreateCXXExprWithTemporaries(Init, 3195 /*ShouldDestroyTemporaries=*/true); 3196 // Attach the initializer to the decl. 3197 VDecl->setInit(Context, Init); 3198 3199 // If the previous declaration of VDecl was a tentative definition, 3200 // remove it from the set of tentative definitions. 3201 if (VDecl->getPreviousDeclaration() && 3202 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3203 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3204 = TentativeDefinitions.find(VDecl->getDeclName()); 3205 assert(Pos != TentativeDefinitions.end() && 3206 "Unrecorded tentative definition?"); 3207 TentativeDefinitions.erase(Pos); 3208 } 3209 3210 return; 3211} 3212 3213void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3214 bool TypeContainsUndeducedAuto) { 3215 Decl *RealDecl = dcl.getAs<Decl>(); 3216 3217 // If there is no declaration, there was an error parsing it. Just ignore it. 3218 if (RealDecl == 0) 3219 return; 3220 3221 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3222 QualType Type = Var->getType(); 3223 3224 // Record tentative definitions. 3225 if (Var->isTentativeDefinition(Context)) 3226 TentativeDefinitions[Var->getDeclName()] = Var; 3227 3228 // C++ [dcl.init.ref]p3: 3229 // The initializer can be omitted for a reference only in a 3230 // parameter declaration (8.3.5), in the declaration of a 3231 // function return type, in the declaration of a class member 3232 // within its class declaration (9.2), and where the extern 3233 // specifier is explicitly used. 3234 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3235 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3236 << Var->getDeclName() 3237 << SourceRange(Var->getLocation(), Var->getLocation()); 3238 Var->setInvalidDecl(); 3239 return; 3240 } 3241 3242 // C++0x [dcl.spec.auto]p3 3243 if (TypeContainsUndeducedAuto) { 3244 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3245 << Var->getDeclName() << Type; 3246 Var->setInvalidDecl(); 3247 return; 3248 } 3249 3250 // C++ [dcl.init]p9: 3251 // 3252 // If no initializer is specified for an object, and the object 3253 // is of (possibly cv-qualified) non-POD class type (or array 3254 // thereof), the object shall be default-initialized; if the 3255 // object is of const-qualified type, the underlying class type 3256 // shall have a user-declared default constructor. 3257 if (getLangOptions().CPlusPlus) { 3258 QualType InitType = Type; 3259 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3260 InitType = Array->getElementType(); 3261 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3262 InitType->isRecordType() && !InitType->isDependentType()) { 3263 CXXRecordDecl *RD = 3264 cast<CXXRecordDecl>(InitType->getAs<RecordType>()->getDecl()); 3265 CXXConstructorDecl *Constructor = 0; 3266 if (!RequireCompleteType(Var->getLocation(), InitType, 3267 diag::err_invalid_incomplete_type_use)) 3268 Constructor 3269 = PerformInitializationByConstructor(InitType, 0, 0, 3270 Var->getLocation(), 3271 SourceRange(Var->getLocation(), 3272 Var->getLocation()), 3273 Var->getDeclName(), 3274 IK_Default); 3275 if (!Constructor) 3276 Var->setInvalidDecl(); 3277 else { 3278 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) { 3279 if (InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0)) 3280 Var->setInvalidDecl(); 3281 } 3282 3283 FinalizeVarWithDestructor(Var, InitType); 3284 } 3285 } 3286 } 3287 3288#if 0 3289 // FIXME: Temporarily disabled because we are not properly parsing 3290 // linkage specifications on declarations, e.g., 3291 // 3292 // extern "C" const CGPoint CGPointerZero; 3293 // 3294 // C++ [dcl.init]p9: 3295 // 3296 // If no initializer is specified for an object, and the 3297 // object is of (possibly cv-qualified) non-POD class type (or 3298 // array thereof), the object shall be default-initialized; if 3299 // the object is of const-qualified type, the underlying class 3300 // type shall have a user-declared default 3301 // constructor. Otherwise, if no initializer is specified for 3302 // an object, the object and its subobjects, if any, have an 3303 // indeterminate initial value; if the object or any of its 3304 // subobjects are of const-qualified type, the program is 3305 // ill-formed. 3306 // 3307 // This isn't technically an error in C, so we don't diagnose it. 3308 // 3309 // FIXME: Actually perform the POD/user-defined default 3310 // constructor check. 3311 if (getLangOptions().CPlusPlus && 3312 Context.getCanonicalType(Type).isConstQualified() && 3313 !Var->hasExternalStorage()) 3314 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3315 << Var->getName() 3316 << SourceRange(Var->getLocation(), Var->getLocation()); 3317#endif 3318 } 3319} 3320 3321Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3322 DeclPtrTy *Group, 3323 unsigned NumDecls) { 3324 llvm::SmallVector<Decl*, 8> Decls; 3325 3326 if (DS.isTypeSpecOwned()) 3327 Decls.push_back((Decl*)DS.getTypeRep()); 3328 3329 for (unsigned i = 0; i != NumDecls; ++i) 3330 if (Decl *D = Group[i].getAs<Decl>()) 3331 Decls.push_back(D); 3332 3333 // Perform semantic analysis that depends on having fully processed both 3334 // the declarator and initializer. 3335 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3336 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3337 if (!IDecl) 3338 continue; 3339 QualType T = IDecl->getType(); 3340 3341 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3342 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3343 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3344 if (!IDecl->isInvalidDecl() && 3345 RequireCompleteType(IDecl->getLocation(), T, 3346 diag::err_typecheck_decl_incomplete_type)) 3347 IDecl->setInvalidDecl(); 3348 } 3349 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3350 // object that has file scope without an initializer, and without a 3351 // storage-class specifier or with the storage-class specifier "static", 3352 // constitutes a tentative definition. Note: A tentative definition with 3353 // external linkage is valid (C99 6.2.2p5). 3354 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3355 if (const IncompleteArrayType *ArrayT 3356 = Context.getAsIncompleteArrayType(T)) { 3357 if (RequireCompleteType(IDecl->getLocation(), 3358 ArrayT->getElementType(), 3359 diag::err_illegal_decl_array_incomplete_type)) 3360 IDecl->setInvalidDecl(); 3361 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3362 // C99 6.9.2p3: If the declaration of an identifier for an object is 3363 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3364 // declared type shall not be an incomplete type. 3365 // NOTE: code such as the following 3366 // static struct s; 3367 // struct s { int a; }; 3368 // is accepted by gcc. Hence here we issue a warning instead of 3369 // an error and we do not invalidate the static declaration. 3370 // NOTE: to avoid multiple warnings, only check the first declaration. 3371 if (IDecl->getPreviousDeclaration() == 0) 3372 RequireCompleteType(IDecl->getLocation(), T, 3373 diag::ext_typecheck_decl_incomplete_type); 3374 } 3375 } 3376 } 3377 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3378 Decls.data(), Decls.size())); 3379} 3380 3381 3382/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3383/// to introduce parameters into function prototype scope. 3384Sema::DeclPtrTy 3385Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3386 const DeclSpec &DS = D.getDeclSpec(); 3387 3388 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3389 VarDecl::StorageClass StorageClass = VarDecl::None; 3390 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3391 StorageClass = VarDecl::Register; 3392 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3393 Diag(DS.getStorageClassSpecLoc(), 3394 diag::err_invalid_storage_class_in_func_decl); 3395 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3396 } 3397 3398 if (D.getDeclSpec().isThreadSpecified()) 3399 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3400 3401 DiagnoseFunctionSpecifiers(D); 3402 3403 // Check that there are no default arguments inside the type of this 3404 // parameter (C++ only). 3405 if (getLangOptions().CPlusPlus) 3406 CheckExtraCXXDefaultArguments(D); 3407 3408 DeclaratorInfo *DInfo = 0; 3409 TagDecl *OwnedDecl = 0; 3410 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3411 &OwnedDecl); 3412 3413 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3414 // C++ [dcl.fct]p6: 3415 // Types shall not be defined in return or parameter types. 3416 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3417 << Context.getTypeDeclType(OwnedDecl); 3418 } 3419 3420 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3421 // Can this happen for params? We already checked that they don't conflict 3422 // among each other. Here they can only shadow globals, which is ok. 3423 IdentifierInfo *II = D.getIdentifier(); 3424 if (II) { 3425 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3426 if (PrevDecl->isTemplateParameter()) { 3427 // Maybe we will complain about the shadowed template parameter. 3428 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3429 // Just pretend that we didn't see the previous declaration. 3430 PrevDecl = 0; 3431 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3432 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3433 3434 // Recover by removing the name 3435 II = 0; 3436 D.SetIdentifier(0, D.getIdentifierLoc()); 3437 } 3438 } 3439 } 3440 3441 // Parameters can not be abstract class types. 3442 // For record types, this is done by the AbstractClassUsageDiagnoser once 3443 // the class has been completely parsed. 3444 if (!CurContext->isRecord() && 3445 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3446 diag::err_abstract_type_in_decl, 3447 AbstractParamType)) 3448 D.setInvalidType(true); 3449 3450 QualType T = adjustParameterType(parmDeclType); 3451 3452 ParmVarDecl *New; 3453 if (T == parmDeclType) // parameter type did not need adjustment 3454 New = ParmVarDecl::Create(Context, CurContext, 3455 D.getIdentifierLoc(), II, 3456 parmDeclType, DInfo, StorageClass, 3457 0); 3458 else // keep track of both the adjusted and unadjusted types 3459 New = OriginalParmVarDecl::Create(Context, CurContext, 3460 D.getIdentifierLoc(), II, T, DInfo, 3461 parmDeclType, StorageClass, 0); 3462 3463 if (D.isInvalidType()) 3464 New->setInvalidDecl(); 3465 3466 // Parameter declarators cannot be interface types. All ObjC objects are 3467 // passed by reference. 3468 if (T->isObjCInterfaceType()) { 3469 Diag(D.getIdentifierLoc(), 3470 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3471 New->setInvalidDecl(); 3472 } 3473 3474 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3475 if (D.getCXXScopeSpec().isSet()) { 3476 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3477 << D.getCXXScopeSpec().getRange(); 3478 New->setInvalidDecl(); 3479 } 3480 3481 // Add the parameter declaration into this scope. 3482 S->AddDecl(DeclPtrTy::make(New)); 3483 if (II) 3484 IdResolver.AddDecl(New); 3485 3486 ProcessDeclAttributes(S, New, D); 3487 3488 if (New->hasAttr<BlocksAttr>()) { 3489 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3490 } 3491 return DeclPtrTy::make(New); 3492} 3493 3494void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3495 SourceLocation LocAfterDecls) { 3496 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3497 "Not a function declarator!"); 3498 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3499 3500 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3501 // for a K&R function. 3502 if (!FTI.hasPrototype) { 3503 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3504 --i; 3505 if (FTI.ArgInfo[i].Param == 0) { 3506 std::string Code = " int "; 3507 Code += FTI.ArgInfo[i].Ident->getName(); 3508 Code += ";\n"; 3509 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3510 << FTI.ArgInfo[i].Ident 3511 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3512 3513 // Implicitly declare the argument as type 'int' for lack of a better 3514 // type. 3515 DeclSpec DS; 3516 const char* PrevSpec; // unused 3517 unsigned DiagID; // unused 3518 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3519 PrevSpec, DiagID); 3520 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3521 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3522 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3523 } 3524 } 3525 } 3526} 3527 3528Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3529 Declarator &D) { 3530 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3531 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3532 "Not a function declarator!"); 3533 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3534 3535 if (FTI.hasPrototype) { 3536 // FIXME: Diagnose arguments without names in C. 3537 } 3538 3539 Scope *ParentScope = FnBodyScope->getParent(); 3540 3541 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3542 MultiTemplateParamsArg(*this), 3543 /*IsFunctionDefinition=*/true); 3544 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3545} 3546 3547Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3548 if (!D) 3549 return D; 3550 FunctionDecl *FD = 0; 3551 3552 if (FunctionTemplateDecl *FunTmpl 3553 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3554 FD = FunTmpl->getTemplatedDecl(); 3555 else 3556 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3557 3558 CurFunctionNeedsScopeChecking = false; 3559 3560 // See if this is a redefinition. 3561 const FunctionDecl *Definition; 3562 if (FD->getBody(Definition)) { 3563 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3564 Diag(Definition->getLocation(), diag::note_previous_definition); 3565 } 3566 3567 // Builtin functions cannot be defined. 3568 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3569 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3570 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3571 FD->setInvalidDecl(); 3572 } 3573 } 3574 3575 // The return type of a function definition must be complete 3576 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3577 QualType ResultType = FD->getResultType(); 3578 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3579 !FD->isInvalidDecl() && 3580 RequireCompleteType(FD->getLocation(), ResultType, 3581 diag::err_func_def_incomplete_result)) 3582 FD->setInvalidDecl(); 3583 3584 // GNU warning -Wmissing-prototypes: 3585 // Warn if a global function is defined without a previous 3586 // prototype declaration. This warning is issued even if the 3587 // definition itself provides a prototype. The aim is to detect 3588 // global functions that fail to be declared in header files. 3589 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3590 !FD->isMain(Context)) { 3591 bool MissingPrototype = true; 3592 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3593 Prev; Prev = Prev->getPreviousDeclaration()) { 3594 // Ignore any declarations that occur in function or method 3595 // scope, because they aren't visible from the header. 3596 if (Prev->getDeclContext()->isFunctionOrMethod()) 3597 continue; 3598 3599 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3600 break; 3601 } 3602 3603 if (MissingPrototype) 3604 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3605 } 3606 3607 if (FnBodyScope) 3608 PushDeclContext(FnBodyScope, FD); 3609 3610 // Check the validity of our function parameters 3611 CheckParmsForFunctionDef(FD); 3612 3613 // Introduce our parameters into the function scope 3614 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3615 ParmVarDecl *Param = FD->getParamDecl(p); 3616 Param->setOwningFunction(FD); 3617 3618 // If this has an identifier, add it to the scope stack. 3619 if (Param->getIdentifier() && FnBodyScope) 3620 PushOnScopeChains(Param, FnBodyScope); 3621 } 3622 3623 // Checking attributes of current function definition 3624 // dllimport attribute. 3625 if (FD->getAttr<DLLImportAttr>() && 3626 (!FD->getAttr<DLLExportAttr>())) { 3627 // dllimport attribute cannot be applied to definition. 3628 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3629 Diag(FD->getLocation(), 3630 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3631 << "dllimport"; 3632 FD->setInvalidDecl(); 3633 return DeclPtrTy::make(FD); 3634 } else { 3635 // If a symbol previously declared dllimport is later defined, the 3636 // attribute is ignored in subsequent references, and a warning is 3637 // emitted. 3638 Diag(FD->getLocation(), 3639 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3640 << FD->getNameAsCString() << "dllimport"; 3641 } 3642 } 3643 return DeclPtrTy::make(FD); 3644} 3645 3646Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3647 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3648} 3649 3650Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3651 bool IsInstantiation) { 3652 Decl *dcl = D.getAs<Decl>(); 3653 Stmt *Body = BodyArg.takeAs<Stmt>(); 3654 3655 FunctionDecl *FD = 0; 3656 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3657 if (FunTmpl) 3658 FD = FunTmpl->getTemplatedDecl(); 3659 else 3660 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3661 3662 if (FD) { 3663 FD->setBody(Body); 3664 if (FD->isMain(Context)) 3665 // C and C++ allow for main to automagically return 0. 3666 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3667 FD->setHasImplicitReturnZero(true); 3668 else 3669 CheckFallThroughForFunctionDef(FD, Body); 3670 3671 if (!FD->isInvalidDecl()) 3672 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3673 3674 // C++ [basic.def.odr]p2: 3675 // [...] A virtual member function is used if it is not pure. [...] 3676 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3677 if (Method->isVirtual() && !Method->isPure()) 3678 MarkDeclarationReferenced(Method->getLocation(), Method); 3679 3680 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3681 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3682 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3683 MD->setBody(Body); 3684 CheckFallThroughForFunctionDef(MD, Body); 3685 MD->setEndLoc(Body->getLocEnd()); 3686 3687 if (!MD->isInvalidDecl()) 3688 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3689 } else { 3690 Body->Destroy(Context); 3691 return DeclPtrTy(); 3692 } 3693 if (!IsInstantiation) 3694 PopDeclContext(); 3695 3696 // Verify and clean out per-function state. 3697 3698 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3699 3700 // Check goto/label use. 3701 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3702 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3703 LabelStmt *L = I->second; 3704 3705 // Verify that we have no forward references left. If so, there was a goto 3706 // or address of a label taken, but no definition of it. Label fwd 3707 // definitions are indicated with a null substmt. 3708 if (L->getSubStmt() != 0) 3709 continue; 3710 3711 // Emit error. 3712 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3713 3714 // At this point, we have gotos that use the bogus label. Stitch it into 3715 // the function body so that they aren't leaked and that the AST is well 3716 // formed. 3717 if (Body == 0) { 3718 // The whole function wasn't parsed correctly, just delete this. 3719 L->Destroy(Context); 3720 continue; 3721 } 3722 3723 // Otherwise, the body is valid: we want to stitch the label decl into the 3724 // function somewhere so that it is properly owned and so that the goto 3725 // has a valid target. Do this by creating a new compound stmt with the 3726 // label in it. 3727 3728 // Give the label a sub-statement. 3729 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3730 3731 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3732 cast<CXXTryStmt>(Body)->getTryBlock() : 3733 cast<CompoundStmt>(Body); 3734 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3735 Elements.push_back(L); 3736 Compound->setStmts(Context, &Elements[0], Elements.size()); 3737 } 3738 FunctionLabelMap.clear(); 3739 3740 if (!Body) return D; 3741 3742 // Verify that that gotos and switch cases don't jump into scopes illegally. 3743 if (CurFunctionNeedsScopeChecking) 3744 DiagnoseInvalidJumps(Body); 3745 3746 // C++ constructors that have function-try-blocks can't have return 3747 // statements in the handlers of that block. (C++ [except.handle]p14) 3748 // Verify this. 3749 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3750 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3751 3752 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3753 Destructor->computeBaseOrMembersToDestroy(Context); 3754 return D; 3755} 3756 3757/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3758/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3759NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3760 IdentifierInfo &II, Scope *S) { 3761 // Before we produce a declaration for an implicitly defined 3762 // function, see whether there was a locally-scoped declaration of 3763 // this name as a function or variable. If so, use that 3764 // (non-visible) declaration, and complain about it. 3765 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3766 = LocallyScopedExternalDecls.find(&II); 3767 if (Pos != LocallyScopedExternalDecls.end()) { 3768 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3769 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3770 return Pos->second; 3771 } 3772 3773 // Extension in C99. Legal in C90, but warn about it. 3774 if (getLangOptions().C99) 3775 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3776 else 3777 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3778 3779 // FIXME: handle stuff like: 3780 // void foo() { extern float X(); } 3781 // void bar() { X(); } <-- implicit decl for X in another scope. 3782 3783 // Set a Declarator for the implicit definition: int foo(); 3784 const char *Dummy; 3785 DeclSpec DS; 3786 unsigned DiagID; 3787 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3788 Error = Error; // Silence warning. 3789 assert(!Error && "Error setting up implicit decl!"); 3790 Declarator D(DS, Declarator::BlockContext); 3791 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3792 0, 0, false, SourceLocation(), 3793 false, 0,0,0, Loc, Loc, D), 3794 SourceLocation()); 3795 D.SetIdentifier(&II, Loc); 3796 3797 // Insert this function into translation-unit scope. 3798 3799 DeclContext *PrevDC = CurContext; 3800 CurContext = Context.getTranslationUnitDecl(); 3801 3802 FunctionDecl *FD = 3803 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3804 FD->setImplicit(); 3805 3806 CurContext = PrevDC; 3807 3808 AddKnownFunctionAttributes(FD); 3809 3810 return FD; 3811} 3812 3813/// \brief Adds any function attributes that we know a priori based on 3814/// the declaration of this function. 3815/// 3816/// These attributes can apply both to implicitly-declared builtins 3817/// (like __builtin___printf_chk) or to library-declared functions 3818/// like NSLog or printf. 3819void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3820 if (FD->isInvalidDecl()) 3821 return; 3822 3823 // If this is a built-in function, map its builtin attributes to 3824 // actual attributes. 3825 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3826 // Handle printf-formatting attributes. 3827 unsigned FormatIdx; 3828 bool HasVAListArg; 3829 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3830 if (!FD->getAttr<FormatAttr>()) 3831 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3832 HasVAListArg ? 0 : FormatIdx + 2)); 3833 } 3834 3835 // Mark const if we don't care about errno and that is the only 3836 // thing preventing the function from being const. This allows 3837 // IRgen to use LLVM intrinsics for such functions. 3838 if (!getLangOptions().MathErrno && 3839 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3840 if (!FD->getAttr<ConstAttr>()) 3841 FD->addAttr(::new (Context) ConstAttr()); 3842 } 3843 3844 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3845 FD->addAttr(::new (Context) NoReturnAttr()); 3846 } 3847 3848 IdentifierInfo *Name = FD->getIdentifier(); 3849 if (!Name) 3850 return; 3851 if ((!getLangOptions().CPlusPlus && 3852 FD->getDeclContext()->isTranslationUnit()) || 3853 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3854 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3855 LinkageSpecDecl::lang_c)) { 3856 // Okay: this could be a libc/libm/Objective-C function we know 3857 // about. 3858 } else 3859 return; 3860 3861 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3862 // FIXME: NSLog and NSLogv should be target specific 3863 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3864 // FIXME: We known better than our headers. 3865 const_cast<FormatAttr *>(Format)->setType("printf"); 3866 } else 3867 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3868 Name->isStr("NSLogv") ? 0 : 2)); 3869 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3870 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 3871 // target-specific builtins, perhaps? 3872 if (!FD->getAttr<FormatAttr>()) 3873 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3874 Name->isStr("vasprintf") ? 0 : 3)); 3875 } 3876} 3877 3878TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3879 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3880 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3881 3882 // Scope manipulation handled by caller. 3883 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3884 D.getIdentifierLoc(), 3885 D.getIdentifier(), 3886 T); 3887 3888 if (TagType *TT = dyn_cast<TagType>(T)) { 3889 TagDecl *TD = TT->getDecl(); 3890 3891 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3892 // keep track of the TypedefDecl. 3893 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3894 TD->setTypedefForAnonDecl(NewTD); 3895 } 3896 3897 if (D.isInvalidType()) 3898 NewTD->setInvalidDecl(); 3899 return NewTD; 3900} 3901 3902 3903/// \brief Determine whether a tag with a given kind is acceptable 3904/// as a redeclaration of the given tag declaration. 3905/// 3906/// \returns true if the new tag kind is acceptable, false otherwise. 3907bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3908 TagDecl::TagKind NewTag, 3909 SourceLocation NewTagLoc, 3910 const IdentifierInfo &Name) { 3911 // C++ [dcl.type.elab]p3: 3912 // The class-key or enum keyword present in the 3913 // elaborated-type-specifier shall agree in kind with the 3914 // declaration to which the name in theelaborated-type-specifier 3915 // refers. This rule also applies to the form of 3916 // elaborated-type-specifier that declares a class-name or 3917 // friend class since it can be construed as referring to the 3918 // definition of the class. Thus, in any 3919 // elaborated-type-specifier, the enum keyword shall be used to 3920 // refer to an enumeration (7.2), the union class-keyshall be 3921 // used to refer to a union (clause 9), and either the class or 3922 // struct class-key shall be used to refer to a class (clause 9) 3923 // declared using the class or struct class-key. 3924 TagDecl::TagKind OldTag = Previous->getTagKind(); 3925 if (OldTag == NewTag) 3926 return true; 3927 3928 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3929 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3930 // Warn about the struct/class tag mismatch. 3931 bool isTemplate = false; 3932 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3933 isTemplate = Record->getDescribedClassTemplate(); 3934 3935 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3936 << (NewTag == TagDecl::TK_class) 3937 << isTemplate << &Name 3938 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3939 OldTag == TagDecl::TK_class? "class" : "struct"); 3940 Diag(Previous->getLocation(), diag::note_previous_use); 3941 return true; 3942 } 3943 return false; 3944} 3945 3946/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3947/// former case, Name will be non-null. In the later case, Name will be null. 3948/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 3949/// reference/declaration/definition of a tag. 3950Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 3951 SourceLocation KWLoc, const CXXScopeSpec &SS, 3952 IdentifierInfo *Name, SourceLocation NameLoc, 3953 AttributeList *Attr, AccessSpecifier AS, 3954 MultiTemplateParamsArg TemplateParameterLists, 3955 bool &OwnedDecl) { 3956 // If this is not a definition, it must have a name. 3957 assert((Name != 0 || TUK == TUK_Definition) && 3958 "Nameless record must be a definition!"); 3959 3960 OwnedDecl = false; 3961 TagDecl::TagKind Kind; 3962 switch (TagSpec) { 3963 default: assert(0 && "Unknown tag type!"); 3964 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3965 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3966 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3967 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3968 } 3969 3970 if (TUK != TUK_Reference) { 3971 if (TemplateParameterList *TemplateParams 3972 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3973 (TemplateParameterList**)TemplateParameterLists.get(), 3974 TemplateParameterLists.size())) { 3975 if (TemplateParams->size() > 0) { 3976 // This is a declaration or definition of a class template (which may 3977 // be a member of another template). 3978 OwnedDecl = false; 3979 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 3980 SS, Name, NameLoc, Attr, 3981 TemplateParams, 3982 AS); 3983 TemplateParameterLists.release(); 3984 return Result.get(); 3985 } else { 3986 // FIXME: diagnose the extraneous 'template<>', once we recover 3987 // slightly better in ParseTemplate.cpp from bogus template 3988 // parameters. 3989 } 3990 } 3991 } 3992 3993 DeclContext *SearchDC = CurContext; 3994 DeclContext *DC = CurContext; 3995 NamedDecl *PrevDecl = 0; 3996 3997 bool Invalid = false; 3998 3999 if (Name && SS.isNotEmpty()) { 4000 // We have a nested-name tag ('struct foo::bar'). 4001 4002 // Check for invalid 'foo::'. 4003 if (SS.isInvalid()) { 4004 Name = 0; 4005 goto CreateNewDecl; 4006 } 4007 4008 if (RequireCompleteDeclContext(SS)) 4009 return DeclPtrTy::make((Decl *)0); 4010 4011 DC = computeDeclContext(SS, true); 4012 SearchDC = DC; 4013 // Look-up name inside 'foo::'. 4014 PrevDecl 4015 = dyn_cast_or_null<TagDecl>( 4016 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4017 4018 // A tag 'foo::bar' must already exist. 4019 if (PrevDecl == 0) { 4020 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4021 Name = 0; 4022 Invalid = true; 4023 goto CreateNewDecl; 4024 } 4025 } else if (Name) { 4026 // If this is a named struct, check to see if there was a previous forward 4027 // declaration or definition. 4028 // FIXME: We're looking into outer scopes here, even when we 4029 // shouldn't be. Doing so can result in ambiguities that we 4030 // shouldn't be diagnosing. 4031 LookupResult R = LookupName(S, Name, LookupTagName, 4032 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4033 if (R.isAmbiguous()) { 4034 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4035 // FIXME: This is not best way to recover from case like: 4036 // 4037 // struct S s; 4038 // 4039 // causes needless "incomplete type" error later. 4040 Name = 0; 4041 PrevDecl = 0; 4042 Invalid = true; 4043 } else 4044 PrevDecl = R; 4045 4046 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4047 // FIXME: This makes sure that we ignore the contexts associated 4048 // with C structs, unions, and enums when looking for a matching 4049 // tag declaration or definition. See the similar lookup tweak 4050 // in Sema::LookupName; is there a better way to deal with this? 4051 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4052 SearchDC = SearchDC->getParent(); 4053 } 4054 } 4055 4056 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4057 // Maybe we will complain about the shadowed template parameter. 4058 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4059 // Just pretend that we didn't see the previous declaration. 4060 PrevDecl = 0; 4061 } 4062 4063 if (PrevDecl) { 4064 // Check whether the previous declaration is usable. 4065 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4066 4067 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4068 // If this is a use of a previous tag, or if the tag is already declared 4069 // in the same scope (so that the definition/declaration completes or 4070 // rementions the tag), reuse the decl. 4071 if (TUK == TUK_Reference || TUK == TUK_Friend || 4072 isDeclInScope(PrevDecl, SearchDC, S)) { 4073 // Make sure that this wasn't declared as an enum and now used as a 4074 // struct or something similar. 4075 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4076 bool SafeToContinue 4077 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4078 Kind != TagDecl::TK_enum); 4079 if (SafeToContinue) 4080 Diag(KWLoc, diag::err_use_with_wrong_tag) 4081 << Name 4082 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4083 PrevTagDecl->getKindName()); 4084 else 4085 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4086 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4087 4088 if (SafeToContinue) 4089 Kind = PrevTagDecl->getTagKind(); 4090 else { 4091 // Recover by making this an anonymous redefinition. 4092 Name = 0; 4093 PrevDecl = 0; 4094 Invalid = true; 4095 } 4096 } 4097 4098 if (!Invalid) { 4099 // If this is a use, just return the declaration we found. 4100 4101 // FIXME: In the future, return a variant or some other clue 4102 // for the consumer of this Decl to know it doesn't own it. 4103 // For our current ASTs this shouldn't be a problem, but will 4104 // need to be changed with DeclGroups. 4105 if (TUK == TUK_Reference) 4106 return DeclPtrTy::make(PrevDecl); 4107 4108 // If this is a friend, make sure we create the new 4109 // declaration in the appropriate semantic context. 4110 if (TUK == TUK_Friend) 4111 SearchDC = PrevDecl->getDeclContext(); 4112 4113 // Diagnose attempts to redefine a tag. 4114 if (TUK == TUK_Definition) { 4115 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4116 Diag(NameLoc, diag::err_redefinition) << Name; 4117 Diag(Def->getLocation(), diag::note_previous_definition); 4118 // If this is a redefinition, recover by making this 4119 // struct be anonymous, which will make any later 4120 // references get the previous definition. 4121 Name = 0; 4122 PrevDecl = 0; 4123 Invalid = true; 4124 } else { 4125 // If the type is currently being defined, complain 4126 // about a nested redefinition. 4127 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4128 if (Tag->isBeingDefined()) { 4129 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4130 Diag(PrevTagDecl->getLocation(), 4131 diag::note_previous_definition); 4132 Name = 0; 4133 PrevDecl = 0; 4134 Invalid = true; 4135 } 4136 } 4137 4138 // Okay, this is definition of a previously declared or referenced 4139 // tag PrevDecl. We're going to create a new Decl for it. 4140 } 4141 } 4142 // If we get here we have (another) forward declaration or we 4143 // have a definition. Just create a new decl. 4144 4145 } else { 4146 // If we get here, this is a definition of a new tag type in a nested 4147 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4148 // new decl/type. We set PrevDecl to NULL so that the entities 4149 // have distinct types. 4150 PrevDecl = 0; 4151 } 4152 // If we get here, we're going to create a new Decl. If PrevDecl 4153 // is non-NULL, it's a definition of the tag declared by 4154 // PrevDecl. If it's NULL, we have a new definition. 4155 } else { 4156 // PrevDecl is a namespace, template, or anything else 4157 // that lives in the IDNS_Tag identifier namespace. 4158 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4159 // The tag name clashes with a namespace name, issue an error and 4160 // recover by making this tag be anonymous. 4161 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4162 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4163 Name = 0; 4164 PrevDecl = 0; 4165 Invalid = true; 4166 } else { 4167 // The existing declaration isn't relevant to us; we're in a 4168 // new scope, so clear out the previous declaration. 4169 PrevDecl = 0; 4170 } 4171 } 4172 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4173 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4174 // C++ [basic.scope.pdecl]p5: 4175 // -- for an elaborated-type-specifier of the form 4176 // 4177 // class-key identifier 4178 // 4179 // if the elaborated-type-specifier is used in the 4180 // decl-specifier-seq or parameter-declaration-clause of a 4181 // function defined in namespace scope, the identifier is 4182 // declared as a class-name in the namespace that contains 4183 // the declaration; otherwise, except as a friend 4184 // declaration, the identifier is declared in the smallest 4185 // non-class, non-function-prototype scope that contains the 4186 // declaration. 4187 // 4188 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4189 // C structs and unions. 4190 // 4191 // GNU C also supports this behavior as part of its incomplete 4192 // enum types extension, while GNU C++ does not. 4193 // 4194 // Find the context where we'll be declaring the tag. 4195 // FIXME: We would like to maintain the current DeclContext as the 4196 // lexical context, 4197 while (SearchDC->isRecord()) 4198 SearchDC = SearchDC->getParent(); 4199 4200 // Find the scope where we'll be declaring the tag. 4201 while (S->isClassScope() || 4202 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4203 ((S->getFlags() & Scope::DeclScope) == 0) || 4204 (S->getEntity() && 4205 ((DeclContext *)S->getEntity())->isTransparentContext())) 4206 S = S->getParent(); 4207 4208 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4209 // C++ [namespace.memdef]p3: 4210 // If a friend declaration in a non-local class first declares a 4211 // class or function, the friend class or function is a member of 4212 // the innermost enclosing namespace. 4213 while (!SearchDC->isFileContext()) 4214 SearchDC = SearchDC->getParent(); 4215 4216 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4217 while (S->getEntity() != SearchDC) 4218 S = S->getParent(); 4219 } 4220 4221CreateNewDecl: 4222 4223 // If there is an identifier, use the location of the identifier as the 4224 // location of the decl, otherwise use the location of the struct/union 4225 // keyword. 4226 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4227 4228 // Otherwise, create a new declaration. If there is a previous 4229 // declaration of the same entity, the two will be linked via 4230 // PrevDecl. 4231 TagDecl *New; 4232 4233 if (Kind == TagDecl::TK_enum) { 4234 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4235 // enum X { A, B, C } D; D should chain to X. 4236 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4237 cast_or_null<EnumDecl>(PrevDecl)); 4238 // If this is an undefined enum, warn. 4239 if (TUK != TUK_Definition && !Invalid) { 4240 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4241 : diag::ext_forward_ref_enum; 4242 Diag(Loc, DK); 4243 } 4244 } else { 4245 // struct/union/class 4246 4247 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4248 // struct X { int A; } D; D should chain to X. 4249 if (getLangOptions().CPlusPlus) 4250 // FIXME: Look for a way to use RecordDecl for simple structs. 4251 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4252 cast_or_null<CXXRecordDecl>(PrevDecl)); 4253 else 4254 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4255 cast_or_null<RecordDecl>(PrevDecl)); 4256 } 4257 4258 if (Kind != TagDecl::TK_enum) { 4259 // Handle #pragma pack: if the #pragma pack stack has non-default 4260 // alignment, make up a packed attribute for this decl. These 4261 // attributes are checked when the ASTContext lays out the 4262 // structure. 4263 // 4264 // It is important for implementing the correct semantics that this 4265 // happen here (in act on tag decl). The #pragma pack stack is 4266 // maintained as a result of parser callbacks which can occur at 4267 // many points during the parsing of a struct declaration (because 4268 // the #pragma tokens are effectively skipped over during the 4269 // parsing of the struct). 4270 if (unsigned Alignment = getPragmaPackAlignment()) 4271 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4272 } 4273 4274 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4275 // C++ [dcl.typedef]p3: 4276 // [...] Similarly, in a given scope, a class or enumeration 4277 // shall not be declared with the same name as a typedef-name 4278 // that is declared in that scope and refers to a type other 4279 // than the class or enumeration itself. 4280 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4281 TypedefDecl *PrevTypedef = 0; 4282 if (Lookup.getKind() == LookupResult::Found) 4283 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4284 4285 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4286 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4287 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4288 Diag(Loc, diag::err_tag_definition_of_typedef) 4289 << Context.getTypeDeclType(New) 4290 << PrevTypedef->getUnderlyingType(); 4291 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4292 Invalid = true; 4293 } 4294 } 4295 4296 if (Invalid) 4297 New->setInvalidDecl(); 4298 4299 if (Attr) 4300 ProcessDeclAttributeList(S, New, Attr); 4301 4302 // If we're declaring or defining a tag in function prototype scope 4303 // in C, note that this type can only be used within the function. 4304 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4305 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4306 4307 // Set the lexical context. If the tag has a C++ scope specifier, the 4308 // lexical context will be different from the semantic context. 4309 New->setLexicalDeclContext(CurContext); 4310 4311 // Set the access specifier. 4312 if (!Invalid && TUK != TUK_Friend) 4313 SetMemberAccessSpecifier(New, PrevDecl, AS); 4314 4315 if (TUK == TUK_Definition) 4316 New->startDefinition(); 4317 4318 // If this has an identifier, add it to the scope stack. 4319 if (Name && TUK != TUK_Friend) { 4320 S = getNonFieldDeclScope(S); 4321 PushOnScopeChains(New, S); 4322 } else { 4323 CurContext->addDecl(New); 4324 } 4325 4326 // If this is the C FILE type, notify the AST context. 4327 if (IdentifierInfo *II = New->getIdentifier()) 4328 if (!New->isInvalidDecl() && 4329 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4330 II->isStr("FILE")) 4331 Context.setFILEDecl(New); 4332 4333 OwnedDecl = true; 4334 return DeclPtrTy::make(New); 4335} 4336 4337void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4338 AdjustDeclIfTemplate(TagD); 4339 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4340 4341 // Enter the tag context. 4342 PushDeclContext(S, Tag); 4343 4344 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4345 FieldCollector->StartClass(); 4346 4347 if (Record->getIdentifier()) { 4348 // C++ [class]p2: 4349 // [...] The class-name is also inserted into the scope of the 4350 // class itself; this is known as the injected-class-name. For 4351 // purposes of access checking, the injected-class-name is treated 4352 // as if it were a public member name. 4353 CXXRecordDecl *InjectedClassName 4354 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4355 CurContext, Record->getLocation(), 4356 Record->getIdentifier(), 4357 Record->getTagKeywordLoc(), 4358 Record); 4359 InjectedClassName->setImplicit(); 4360 InjectedClassName->setAccess(AS_public); 4361 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4362 InjectedClassName->setDescribedClassTemplate(Template); 4363 PushOnScopeChains(InjectedClassName, S); 4364 assert(InjectedClassName->isInjectedClassName() && 4365 "Broken injected-class-name"); 4366 } 4367 } 4368} 4369 4370void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4371 SourceLocation RBraceLoc) { 4372 AdjustDeclIfTemplate(TagD); 4373 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4374 Tag->setRBraceLoc(RBraceLoc); 4375 4376 if (isa<CXXRecordDecl>(Tag)) 4377 FieldCollector->FinishClass(); 4378 4379 // Exit this scope of this tag's definition. 4380 PopDeclContext(); 4381 4382 // Notify the consumer that we've defined a tag. 4383 Consumer.HandleTagDeclDefinition(Tag); 4384} 4385 4386// Note that FieldName may be null for anonymous bitfields. 4387bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4388 QualType FieldTy, const Expr *BitWidth, 4389 bool *ZeroWidth) { 4390 // Default to true; that shouldn't confuse checks for emptiness 4391 if (ZeroWidth) 4392 *ZeroWidth = true; 4393 4394 // C99 6.7.2.1p4 - verify the field type. 4395 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4396 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4397 // Handle incomplete types with specific error. 4398 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4399 return true; 4400 if (FieldName) 4401 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4402 << FieldName << FieldTy << BitWidth->getSourceRange(); 4403 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4404 << FieldTy << BitWidth->getSourceRange(); 4405 } 4406 4407 // If the bit-width is type- or value-dependent, don't try to check 4408 // it now. 4409 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4410 return false; 4411 4412 llvm::APSInt Value; 4413 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4414 return true; 4415 4416 if (Value != 0 && ZeroWidth) 4417 *ZeroWidth = false; 4418 4419 // Zero-width bitfield is ok for anonymous field. 4420 if (Value == 0 && FieldName) 4421 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4422 4423 if (Value.isSigned() && Value.isNegative()) { 4424 if (FieldName) 4425 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4426 << FieldName << Value.toString(10); 4427 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4428 << Value.toString(10); 4429 } 4430 4431 if (!FieldTy->isDependentType()) { 4432 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4433 if (Value.getZExtValue() > TypeSize) { 4434 if (FieldName) 4435 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4436 << FieldName << (unsigned)TypeSize; 4437 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4438 << (unsigned)TypeSize; 4439 } 4440 } 4441 4442 return false; 4443} 4444 4445/// ActOnField - Each field of a struct/union/class is passed into this in order 4446/// to create a FieldDecl object for it. 4447Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4448 SourceLocation DeclStart, 4449 Declarator &D, ExprTy *BitfieldWidth) { 4450 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4451 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4452 AS_public); 4453 return DeclPtrTy::make(Res); 4454} 4455 4456/// HandleField - Analyze a field of a C struct or a C++ data member. 4457/// 4458FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4459 SourceLocation DeclStart, 4460 Declarator &D, Expr *BitWidth, 4461 AccessSpecifier AS) { 4462 IdentifierInfo *II = D.getIdentifier(); 4463 SourceLocation Loc = DeclStart; 4464 if (II) Loc = D.getIdentifierLoc(); 4465 4466 DeclaratorInfo *DInfo = 0; 4467 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4468 if (getLangOptions().CPlusPlus) 4469 CheckExtraCXXDefaultArguments(D); 4470 4471 DiagnoseFunctionSpecifiers(D); 4472 4473 if (D.getDeclSpec().isThreadSpecified()) 4474 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4475 4476 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4477 4478 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4479 // Maybe we will complain about the shadowed template parameter. 4480 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4481 // Just pretend that we didn't see the previous declaration. 4482 PrevDecl = 0; 4483 } 4484 4485 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4486 PrevDecl = 0; 4487 4488 bool Mutable 4489 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4490 SourceLocation TSSL = D.getSourceRange().getBegin(); 4491 FieldDecl *NewFD 4492 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4493 AS, PrevDecl, &D); 4494 if (NewFD->isInvalidDecl() && PrevDecl) { 4495 // Don't introduce NewFD into scope; there's already something 4496 // with the same name in the same scope. 4497 } else if (II) { 4498 PushOnScopeChains(NewFD, S); 4499 } else 4500 Record->addDecl(NewFD); 4501 4502 return NewFD; 4503} 4504 4505/// \brief Build a new FieldDecl and check its well-formedness. 4506/// 4507/// This routine builds a new FieldDecl given the fields name, type, 4508/// record, etc. \p PrevDecl should refer to any previous declaration 4509/// with the same name and in the same scope as the field to be 4510/// created. 4511/// 4512/// \returns a new FieldDecl. 4513/// 4514/// \todo The Declarator argument is a hack. It will be removed once 4515FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4516 DeclaratorInfo *DInfo, 4517 RecordDecl *Record, SourceLocation Loc, 4518 bool Mutable, Expr *BitWidth, 4519 SourceLocation TSSL, 4520 AccessSpecifier AS, NamedDecl *PrevDecl, 4521 Declarator *D) { 4522 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4523 bool InvalidDecl = false; 4524 if (D) InvalidDecl = D->isInvalidType(); 4525 4526 // If we receive a broken type, recover by assuming 'int' and 4527 // marking this declaration as invalid. 4528 if (T.isNull()) { 4529 InvalidDecl = true; 4530 T = Context.IntTy; 4531 } 4532 4533 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4534 // than a variably modified type. 4535 if (T->isVariablyModifiedType()) { 4536 bool SizeIsNegative; 4537 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4538 SizeIsNegative); 4539 if (!FixedTy.isNull()) { 4540 Diag(Loc, diag::warn_illegal_constant_array_size); 4541 T = FixedTy; 4542 } else { 4543 if (SizeIsNegative) 4544 Diag(Loc, diag::err_typecheck_negative_array_size); 4545 else 4546 Diag(Loc, diag::err_typecheck_field_variable_size); 4547 InvalidDecl = true; 4548 } 4549 } 4550 4551 // Fields can not have abstract class types 4552 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4553 AbstractFieldType)) 4554 InvalidDecl = true; 4555 4556 bool ZeroWidth = false; 4557 // If this is declared as a bit-field, check the bit-field. 4558 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4559 InvalidDecl = true; 4560 DeleteExpr(BitWidth); 4561 BitWidth = 0; 4562 ZeroWidth = false; 4563 } 4564 4565 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4566 BitWidth, Mutable); 4567 if (InvalidDecl) 4568 NewFD->setInvalidDecl(); 4569 4570 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4571 Diag(Loc, diag::err_duplicate_member) << II; 4572 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4573 NewFD->setInvalidDecl(); 4574 } 4575 4576 if (getLangOptions().CPlusPlus) { 4577 QualType EltTy = Context.getBaseElementType(T); 4578 4579 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4580 4581 if (!T->isPODType()) 4582 CXXRecord->setPOD(false); 4583 if (!ZeroWidth) 4584 CXXRecord->setEmpty(false); 4585 4586 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4587 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4588 4589 if (!RDecl->hasTrivialConstructor()) 4590 CXXRecord->setHasTrivialConstructor(false); 4591 if (!RDecl->hasTrivialCopyConstructor()) 4592 CXXRecord->setHasTrivialCopyConstructor(false); 4593 if (!RDecl->hasTrivialCopyAssignment()) 4594 CXXRecord->setHasTrivialCopyAssignment(false); 4595 if (!RDecl->hasTrivialDestructor()) 4596 CXXRecord->setHasTrivialDestructor(false); 4597 4598 // C++ 9.5p1: An object of a class with a non-trivial 4599 // constructor, a non-trivial copy constructor, a non-trivial 4600 // destructor, or a non-trivial copy assignment operator 4601 // cannot be a member of a union, nor can an array of such 4602 // objects. 4603 // TODO: C++0x alters this restriction significantly. 4604 if (Record->isUnion()) { 4605 // We check for copy constructors before constructors 4606 // because otherwise we'll never get complaints about 4607 // copy constructors. 4608 4609 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4610 4611 CXXSpecialMember member; 4612 if (!RDecl->hasTrivialCopyConstructor()) 4613 member = CXXCopyConstructor; 4614 else if (!RDecl->hasTrivialConstructor()) 4615 member = CXXDefaultConstructor; 4616 else if (!RDecl->hasTrivialCopyAssignment()) 4617 member = CXXCopyAssignment; 4618 else if (!RDecl->hasTrivialDestructor()) 4619 member = CXXDestructor; 4620 else 4621 member = invalid; 4622 4623 if (member != invalid) { 4624 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4625 DiagnoseNontrivial(RT, member); 4626 NewFD->setInvalidDecl(); 4627 } 4628 } 4629 } 4630 } 4631 4632 // FIXME: We need to pass in the attributes given an AST 4633 // representation, not a parser representation. 4634 if (D) 4635 // FIXME: What to pass instead of TUScope? 4636 ProcessDeclAttributes(TUScope, NewFD, *D); 4637 4638 if (T.isObjCGCWeak()) 4639 Diag(Loc, diag::warn_attribute_weak_on_field); 4640 4641 NewFD->setAccess(AS); 4642 4643 // C++ [dcl.init.aggr]p1: 4644 // An aggregate is an array or a class (clause 9) with [...] no 4645 // private or protected non-static data members (clause 11). 4646 // A POD must be an aggregate. 4647 if (getLangOptions().CPlusPlus && 4648 (AS == AS_private || AS == AS_protected)) { 4649 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4650 CXXRecord->setAggregate(false); 4651 CXXRecord->setPOD(false); 4652 } 4653 4654 return NewFD; 4655} 4656 4657/// DiagnoseNontrivial - Given that a class has a non-trivial 4658/// special member, figure out why. 4659void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4660 QualType QT(T, 0U); 4661 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4662 4663 // Check whether the member was user-declared. 4664 switch (member) { 4665 case CXXDefaultConstructor: 4666 if (RD->hasUserDeclaredConstructor()) { 4667 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4668 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4669 if (!ci->isImplicitlyDefined(Context)) { 4670 SourceLocation CtorLoc = ci->getLocation(); 4671 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4672 return; 4673 } 4674 4675 assert(0 && "found no user-declared constructors"); 4676 return; 4677 } 4678 break; 4679 4680 case CXXCopyConstructor: 4681 if (RD->hasUserDeclaredCopyConstructor()) { 4682 SourceLocation CtorLoc = 4683 RD->getCopyConstructor(Context, 0)->getLocation(); 4684 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4685 return; 4686 } 4687 break; 4688 4689 case CXXCopyAssignment: 4690 if (RD->hasUserDeclaredCopyAssignment()) { 4691 // FIXME: this should use the location of the copy 4692 // assignment, not the type. 4693 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4694 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4695 return; 4696 } 4697 break; 4698 4699 case CXXDestructor: 4700 if (RD->hasUserDeclaredDestructor()) { 4701 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4702 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4703 return; 4704 } 4705 break; 4706 } 4707 4708 typedef CXXRecordDecl::base_class_iterator base_iter; 4709 4710 // Virtual bases and members inhibit trivial copying/construction, 4711 // but not trivial destruction. 4712 if (member != CXXDestructor) { 4713 // Check for virtual bases. vbases includes indirect virtual bases, 4714 // so we just iterate through the direct bases. 4715 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4716 if (bi->isVirtual()) { 4717 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4718 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4719 return; 4720 } 4721 4722 // Check for virtual methods. 4723 typedef CXXRecordDecl::method_iterator meth_iter; 4724 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4725 ++mi) { 4726 if (mi->isVirtual()) { 4727 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4728 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4729 return; 4730 } 4731 } 4732 } 4733 4734 bool (CXXRecordDecl::*hasTrivial)() const; 4735 switch (member) { 4736 case CXXDefaultConstructor: 4737 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4738 case CXXCopyConstructor: 4739 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4740 case CXXCopyAssignment: 4741 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4742 case CXXDestructor: 4743 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4744 default: 4745 assert(0 && "unexpected special member"); return; 4746 } 4747 4748 // Check for nontrivial bases (and recurse). 4749 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4750 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4751 assert(BaseRT); 4752 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4753 if (!(BaseRecTy->*hasTrivial)()) { 4754 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4755 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4756 DiagnoseNontrivial(BaseRT, member); 4757 return; 4758 } 4759 } 4760 4761 // Check for nontrivial members (and recurse). 4762 typedef RecordDecl::field_iterator field_iter; 4763 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4764 ++fi) { 4765 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4766 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4767 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4768 4769 if (!(EltRD->*hasTrivial)()) { 4770 SourceLocation FLoc = (*fi)->getLocation(); 4771 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4772 DiagnoseNontrivial(EltRT, member); 4773 return; 4774 } 4775 } 4776 } 4777 4778 assert(0 && "found no explanation for non-trivial member"); 4779} 4780 4781/// TranslateIvarVisibility - Translate visibility from a token ID to an 4782/// AST enum value. 4783static ObjCIvarDecl::AccessControl 4784TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4785 switch (ivarVisibility) { 4786 default: assert(0 && "Unknown visitibility kind"); 4787 case tok::objc_private: return ObjCIvarDecl::Private; 4788 case tok::objc_public: return ObjCIvarDecl::Public; 4789 case tok::objc_protected: return ObjCIvarDecl::Protected; 4790 case tok::objc_package: return ObjCIvarDecl::Package; 4791 } 4792} 4793 4794/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4795/// in order to create an IvarDecl object for it. 4796Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4797 SourceLocation DeclStart, 4798 DeclPtrTy IntfDecl, 4799 Declarator &D, ExprTy *BitfieldWidth, 4800 tok::ObjCKeywordKind Visibility) { 4801 4802 IdentifierInfo *II = D.getIdentifier(); 4803 Expr *BitWidth = (Expr*)BitfieldWidth; 4804 SourceLocation Loc = DeclStart; 4805 if (II) Loc = D.getIdentifierLoc(); 4806 4807 // FIXME: Unnamed fields can be handled in various different ways, for 4808 // example, unnamed unions inject all members into the struct namespace! 4809 4810 DeclaratorInfo *DInfo = 0; 4811 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4812 4813 if (BitWidth) { 4814 // 6.7.2.1p3, 6.7.2.1p4 4815 if (VerifyBitField(Loc, II, T, BitWidth)) { 4816 D.setInvalidType(); 4817 DeleteExpr(BitWidth); 4818 BitWidth = 0; 4819 } 4820 } else { 4821 // Not a bitfield. 4822 4823 // validate II. 4824 4825 } 4826 4827 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4828 // than a variably modified type. 4829 if (T->isVariablyModifiedType()) { 4830 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4831 D.setInvalidType(); 4832 } 4833 4834 // Get the visibility (access control) for this ivar. 4835 ObjCIvarDecl::AccessControl ac = 4836 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4837 : ObjCIvarDecl::None; 4838 // Must set ivar's DeclContext to its enclosing interface. 4839 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4840 DeclContext *EnclosingContext; 4841 if (ObjCImplementationDecl *IMPDecl = 4842 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4843 // Case of ivar declared in an implementation. Context is that of its class. 4844 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4845 assert(IDecl && "No class- ActOnIvar"); 4846 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4847 } else 4848 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4849 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4850 4851 // Construct the decl. 4852 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4853 EnclosingContext, Loc, II, T, 4854 DInfo, ac, (Expr *)BitfieldWidth); 4855 4856 if (II) { 4857 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4858 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4859 && !isa<TagDecl>(PrevDecl)) { 4860 Diag(Loc, diag::err_duplicate_member) << II; 4861 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4862 NewID->setInvalidDecl(); 4863 } 4864 } 4865 4866 // Process attributes attached to the ivar. 4867 ProcessDeclAttributes(S, NewID, D); 4868 4869 if (D.isInvalidType()) 4870 NewID->setInvalidDecl(); 4871 4872 if (II) { 4873 // FIXME: When interfaces are DeclContexts, we'll need to add 4874 // these to the interface. 4875 S->AddDecl(DeclPtrTy::make(NewID)); 4876 IdResolver.AddDecl(NewID); 4877 } 4878 4879 return DeclPtrTy::make(NewID); 4880} 4881 4882void Sema::ActOnFields(Scope* S, 4883 SourceLocation RecLoc, DeclPtrTy RecDecl, 4884 DeclPtrTy *Fields, unsigned NumFields, 4885 SourceLocation LBrac, SourceLocation RBrac, 4886 AttributeList *Attr) { 4887 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4888 assert(EnclosingDecl && "missing record or interface decl"); 4889 4890 // If the decl this is being inserted into is invalid, then it may be a 4891 // redeclaration or some other bogus case. Don't try to add fields to it. 4892 if (EnclosingDecl->isInvalidDecl()) { 4893 // FIXME: Deallocate fields? 4894 return; 4895 } 4896 4897 4898 // Verify that all the fields are okay. 4899 unsigned NumNamedMembers = 0; 4900 llvm::SmallVector<FieldDecl*, 32> RecFields; 4901 4902 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4903 for (unsigned i = 0; i != NumFields; ++i) { 4904 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4905 4906 // Get the type for the field. 4907 Type *FDTy = FD->getType().getTypePtr(); 4908 4909 if (!FD->isAnonymousStructOrUnion()) { 4910 // Remember all fields written by the user. 4911 RecFields.push_back(FD); 4912 } 4913 4914 // If the field is already invalid for some reason, don't emit more 4915 // diagnostics about it. 4916 if (FD->isInvalidDecl()) 4917 continue; 4918 4919 // C99 6.7.2.1p2: 4920 // A structure or union shall not contain a member with 4921 // incomplete or function type (hence, a structure shall not 4922 // contain an instance of itself, but may contain a pointer to 4923 // an instance of itself), except that the last member of a 4924 // structure with more than one named member may have incomplete 4925 // array type; such a structure (and any union containing, 4926 // possibly recursively, a member that is such a structure) 4927 // shall not be a member of a structure or an element of an 4928 // array. 4929 if (FDTy->isFunctionType()) { 4930 // Field declared as a function. 4931 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4932 << FD->getDeclName(); 4933 FD->setInvalidDecl(); 4934 EnclosingDecl->setInvalidDecl(); 4935 continue; 4936 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4937 Record && Record->isStruct()) { 4938 // Flexible array member. 4939 if (NumNamedMembers < 1) { 4940 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4941 << FD->getDeclName(); 4942 FD->setInvalidDecl(); 4943 EnclosingDecl->setInvalidDecl(); 4944 continue; 4945 } 4946 // Okay, we have a legal flexible array member at the end of the struct. 4947 if (Record) 4948 Record->setHasFlexibleArrayMember(true); 4949 } else if (!FDTy->isDependentType() && 4950 RequireCompleteType(FD->getLocation(), FD->getType(), 4951 diag::err_field_incomplete)) { 4952 // Incomplete type 4953 FD->setInvalidDecl(); 4954 EnclosingDecl->setInvalidDecl(); 4955 continue; 4956 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 4957 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4958 // If this is a member of a union, then entire union becomes "flexible". 4959 if (Record && Record->isUnion()) { 4960 Record->setHasFlexibleArrayMember(true); 4961 } else { 4962 // If this is a struct/class and this is not the last element, reject 4963 // it. Note that GCC supports variable sized arrays in the middle of 4964 // structures. 4965 if (i != NumFields-1) 4966 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4967 << FD->getDeclName() << FD->getType(); 4968 else { 4969 // We support flexible arrays at the end of structs in 4970 // other structs as an extension. 4971 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4972 << FD->getDeclName(); 4973 if (Record) 4974 Record->setHasFlexibleArrayMember(true); 4975 } 4976 } 4977 } 4978 if (Record && FDTTy->getDecl()->hasObjectMember()) 4979 Record->setHasObjectMember(true); 4980 } else if (FDTy->isObjCInterfaceType()) { 4981 /// A field cannot be an Objective-c object 4982 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4983 FD->setInvalidDecl(); 4984 EnclosingDecl->setInvalidDecl(); 4985 continue; 4986 } else if (getLangOptions().ObjC1 && 4987 getLangOptions().getGCMode() != LangOptions::NonGC && 4988 Record && 4989 (FD->getType()->isObjCObjectPointerType() || 4990 FD->getType().isObjCGCStrong())) 4991 Record->setHasObjectMember(true); 4992 // Keep track of the number of named members. 4993 if (FD->getIdentifier()) 4994 ++NumNamedMembers; 4995 } 4996 4997 // Okay, we successfully defined 'Record'. 4998 if (Record) { 4999 Record->completeDefinition(Context); 5000 } else { 5001 ObjCIvarDecl **ClsFields = 5002 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5003 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5004 ID->setIVarList(ClsFields, RecFields.size(), Context); 5005 ID->setLocEnd(RBrac); 5006 // Add ivar's to class's DeclContext. 5007 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5008 ClsFields[i]->setLexicalDeclContext(ID); 5009 ID->addDecl(ClsFields[i]); 5010 } 5011 // Must enforce the rule that ivars in the base classes may not be 5012 // duplicates. 5013 if (ID->getSuperClass()) { 5014 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5015 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5016 ObjCIvarDecl* Ivar = (*IVI); 5017 5018 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5019 ObjCIvarDecl* prevIvar = 5020 ID->getSuperClass()->lookupInstanceVariable(II); 5021 if (prevIvar) { 5022 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5023 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5024 } 5025 } 5026 } 5027 } 5028 } else if (ObjCImplementationDecl *IMPDecl = 5029 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5030 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5031 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5032 // Ivar declared in @implementation never belongs to the implementation. 5033 // Only it is in implementation's lexical context. 5034 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5035 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5036 } 5037 } 5038 5039 if (Attr) 5040 ProcessDeclAttributeList(S, Record, Attr); 5041} 5042 5043EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5044 EnumConstantDecl *LastEnumConst, 5045 SourceLocation IdLoc, 5046 IdentifierInfo *Id, 5047 ExprArg val) { 5048 Expr *Val = (Expr *)val.get(); 5049 5050 llvm::APSInt EnumVal(32); 5051 QualType EltTy; 5052 if (Val && !Val->isTypeDependent()) { 5053 // Make sure to promote the operand type to int. 5054 UsualUnaryConversions(Val); 5055 if (Val != val.get()) { 5056 val.release(); 5057 val = Val; 5058 } 5059 5060 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5061 SourceLocation ExpLoc; 5062 if (!Val->isValueDependent() && 5063 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5064 Val = 0; 5065 } else { 5066 EltTy = Val->getType(); 5067 } 5068 } 5069 5070 if (!Val) { 5071 if (LastEnumConst) { 5072 // Assign the last value + 1. 5073 EnumVal = LastEnumConst->getInitVal(); 5074 ++EnumVal; 5075 5076 // Check for overflow on increment. 5077 if (EnumVal < LastEnumConst->getInitVal()) 5078 Diag(IdLoc, diag::warn_enum_value_overflow); 5079 5080 EltTy = LastEnumConst->getType(); 5081 } else { 5082 // First value, set to zero. 5083 EltTy = Context.IntTy; 5084 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5085 } 5086 } 5087 5088 val.release(); 5089 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5090 Val, EnumVal); 5091} 5092 5093 5094Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5095 DeclPtrTy lastEnumConst, 5096 SourceLocation IdLoc, 5097 IdentifierInfo *Id, 5098 SourceLocation EqualLoc, ExprTy *val) { 5099 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5100 EnumConstantDecl *LastEnumConst = 5101 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5102 Expr *Val = static_cast<Expr*>(val); 5103 5104 // The scope passed in may not be a decl scope. Zip up the scope tree until 5105 // we find one that is. 5106 S = getNonFieldDeclScope(S); 5107 5108 // Verify that there isn't already something declared with this name in this 5109 // scope. 5110 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5111 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5112 // Maybe we will complain about the shadowed template parameter. 5113 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5114 // Just pretend that we didn't see the previous declaration. 5115 PrevDecl = 0; 5116 } 5117 5118 if (PrevDecl) { 5119 // When in C++, we may get a TagDecl with the same name; in this case the 5120 // enum constant will 'hide' the tag. 5121 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5122 "Received TagDecl when not in C++!"); 5123 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5124 if (isa<EnumConstantDecl>(PrevDecl)) 5125 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5126 else 5127 Diag(IdLoc, diag::err_redefinition) << Id; 5128 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5129 if (Val) Val->Destroy(Context); 5130 return DeclPtrTy(); 5131 } 5132 } 5133 5134 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5135 IdLoc, Id, Owned(Val)); 5136 5137 // Register this decl in the current scope stack. 5138 if (New) 5139 PushOnScopeChains(New, S); 5140 5141 return DeclPtrTy::make(New); 5142} 5143 5144void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5145 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5146 DeclPtrTy *Elements, unsigned NumElements, 5147 Scope *S, AttributeList *Attr) { 5148 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5149 QualType EnumType = Context.getTypeDeclType(Enum); 5150 5151 if (Attr) 5152 ProcessDeclAttributeList(S, Enum, Attr); 5153 5154 // TODO: If the result value doesn't fit in an int, it must be a long or long 5155 // long value. ISO C does not support this, but GCC does as an extension, 5156 // emit a warning. 5157 unsigned IntWidth = Context.Target.getIntWidth(); 5158 unsigned CharWidth = Context.Target.getCharWidth(); 5159 unsigned ShortWidth = Context.Target.getShortWidth(); 5160 5161 // Verify that all the values are okay, compute the size of the values, and 5162 // reverse the list. 5163 unsigned NumNegativeBits = 0; 5164 unsigned NumPositiveBits = 0; 5165 5166 // Keep track of whether all elements have type int. 5167 bool AllElementsInt = true; 5168 5169 for (unsigned i = 0; i != NumElements; ++i) { 5170 EnumConstantDecl *ECD = 5171 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5172 if (!ECD) continue; // Already issued a diagnostic. 5173 5174 // If the enum value doesn't fit in an int, emit an extension warning. 5175 const llvm::APSInt &InitVal = ECD->getInitVal(); 5176 assert(InitVal.getBitWidth() >= IntWidth && 5177 "Should have promoted value to int"); 5178 if (InitVal.getBitWidth() > IntWidth) { 5179 llvm::APSInt V(InitVal); 5180 V.trunc(IntWidth); 5181 V.extend(InitVal.getBitWidth()); 5182 if (V != InitVal) 5183 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5184 << InitVal.toString(10); 5185 } 5186 5187 // Keep track of the size of positive and negative values. 5188 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5189 NumPositiveBits = std::max(NumPositiveBits, 5190 (unsigned)InitVal.getActiveBits()); 5191 else 5192 NumNegativeBits = std::max(NumNegativeBits, 5193 (unsigned)InitVal.getMinSignedBits()); 5194 5195 // Keep track of whether every enum element has type int (very commmon). 5196 if (AllElementsInt) 5197 AllElementsInt = ECD->getType() == Context.IntTy; 5198 } 5199 5200 // Figure out the type that should be used for this enum. 5201 // FIXME: Support -fshort-enums. 5202 QualType BestType; 5203 unsigned BestWidth; 5204 5205 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5206 5207 if (NumNegativeBits) { 5208 // If there is a negative value, figure out the smallest integer type (of 5209 // int/long/longlong) that fits. 5210 // If it's packed, check also if it fits a char or a short. 5211 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5212 BestType = Context.SignedCharTy; 5213 BestWidth = CharWidth; 5214 } else if (Packed && NumNegativeBits <= ShortWidth && 5215 NumPositiveBits < ShortWidth) { 5216 BestType = Context.ShortTy; 5217 BestWidth = ShortWidth; 5218 } 5219 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5220 BestType = Context.IntTy; 5221 BestWidth = IntWidth; 5222 } else { 5223 BestWidth = Context.Target.getLongWidth(); 5224 5225 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5226 BestType = Context.LongTy; 5227 else { 5228 BestWidth = Context.Target.getLongLongWidth(); 5229 5230 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5231 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5232 BestType = Context.LongLongTy; 5233 } 5234 } 5235 } else { 5236 // If there is no negative value, figure out which of uint, ulong, ulonglong 5237 // fits. 5238 // If it's packed, check also if it fits a char or a short. 5239 if (Packed && NumPositiveBits <= CharWidth) { 5240 BestType = Context.UnsignedCharTy; 5241 BestWidth = CharWidth; 5242 } else if (Packed && NumPositiveBits <= ShortWidth) { 5243 BestType = Context.UnsignedShortTy; 5244 BestWidth = ShortWidth; 5245 } 5246 else if (NumPositiveBits <= IntWidth) { 5247 BestType = Context.UnsignedIntTy; 5248 BestWidth = IntWidth; 5249 } else if (NumPositiveBits <= 5250 (BestWidth = Context.Target.getLongWidth())) { 5251 BestType = Context.UnsignedLongTy; 5252 } else { 5253 BestWidth = Context.Target.getLongLongWidth(); 5254 assert(NumPositiveBits <= BestWidth && 5255 "How could an initializer get larger than ULL?"); 5256 BestType = Context.UnsignedLongLongTy; 5257 } 5258 } 5259 5260 // Loop over all of the enumerator constants, changing their types to match 5261 // the type of the enum if needed. 5262 for (unsigned i = 0; i != NumElements; ++i) { 5263 EnumConstantDecl *ECD = 5264 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5265 if (!ECD) continue; // Already issued a diagnostic. 5266 5267 // Standard C says the enumerators have int type, but we allow, as an 5268 // extension, the enumerators to be larger than int size. If each 5269 // enumerator value fits in an int, type it as an int, otherwise type it the 5270 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5271 // that X has type 'int', not 'unsigned'. 5272 if (ECD->getType() == Context.IntTy) { 5273 // Make sure the init value is signed. 5274 llvm::APSInt IV = ECD->getInitVal(); 5275 IV.setIsSigned(true); 5276 ECD->setInitVal(IV); 5277 5278 if (getLangOptions().CPlusPlus) 5279 // C++ [dcl.enum]p4: Following the closing brace of an 5280 // enum-specifier, each enumerator has the type of its 5281 // enumeration. 5282 ECD->setType(EnumType); 5283 continue; // Already int type. 5284 } 5285 5286 // Determine whether the value fits into an int. 5287 llvm::APSInt InitVal = ECD->getInitVal(); 5288 bool FitsInInt; 5289 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5290 FitsInInt = InitVal.getActiveBits() < IntWidth; 5291 else 5292 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5293 5294 // If it fits into an integer type, force it. Otherwise force it to match 5295 // the enum decl type. 5296 QualType NewTy; 5297 unsigned NewWidth; 5298 bool NewSign; 5299 if (FitsInInt) { 5300 NewTy = Context.IntTy; 5301 NewWidth = IntWidth; 5302 NewSign = true; 5303 } else if (ECD->getType() == BestType) { 5304 // Already the right type! 5305 if (getLangOptions().CPlusPlus) 5306 // C++ [dcl.enum]p4: Following the closing brace of an 5307 // enum-specifier, each enumerator has the type of its 5308 // enumeration. 5309 ECD->setType(EnumType); 5310 continue; 5311 } else { 5312 NewTy = BestType; 5313 NewWidth = BestWidth; 5314 NewSign = BestType->isSignedIntegerType(); 5315 } 5316 5317 // Adjust the APSInt value. 5318 InitVal.extOrTrunc(NewWidth); 5319 InitVal.setIsSigned(NewSign); 5320 ECD->setInitVal(InitVal); 5321 5322 // Adjust the Expr initializer and type. 5323 if (ECD->getInitExpr()) 5324 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5325 CastExpr::CK_Unknown, 5326 ECD->getInitExpr(), 5327 /*isLvalue=*/false)); 5328 if (getLangOptions().CPlusPlus) 5329 // C++ [dcl.enum]p4: Following the closing brace of an 5330 // enum-specifier, each enumerator has the type of its 5331 // enumeration. 5332 ECD->setType(EnumType); 5333 else 5334 ECD->setType(NewTy); 5335 } 5336 5337 Enum->completeDefinition(Context, BestType); 5338} 5339 5340Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5341 ExprArg expr) { 5342 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5343 5344 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5345 Loc, AsmString); 5346 CurContext->addDecl(New); 5347 return DeclPtrTy::make(New); 5348} 5349 5350void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5351 SourceLocation PragmaLoc, 5352 SourceLocation NameLoc) { 5353 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5354 5355 if (PrevDecl) { 5356 PrevDecl->addAttr(::new (Context) WeakAttr()); 5357 } else { 5358 (void)WeakUndeclaredIdentifiers.insert( 5359 std::pair<IdentifierInfo*,WeakInfo> 5360 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5361 } 5362} 5363 5364void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5365 IdentifierInfo* AliasName, 5366 SourceLocation PragmaLoc, 5367 SourceLocation NameLoc, 5368 SourceLocation AliasNameLoc) { 5369 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5370 WeakInfo W = WeakInfo(Name, NameLoc); 5371 5372 if (PrevDecl) { 5373 if (!PrevDecl->hasAttr<AliasAttr>()) 5374 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5375 DeclApplyPragmaWeak(TUScope, ND, W); 5376 } else { 5377 (void)WeakUndeclaredIdentifiers.insert( 5378 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5379 } 5380} 5381