SemaDecl.cpp revision f6b1185f0a8a209c06dfc1efdb6a59cc851e970c
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 "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.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/PartialDiagnostic.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/Basic/TargetInfo.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/BitVector.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37#include <queue> 38using namespace clang; 39 40/// getDeclName - Return a pretty name for the specified decl if possible, or 41/// an empty string if not. This is used for pretty crash reporting. 42std::string Sema::getDeclName(DeclPtrTy d) { 43 Decl *D = d.getAs<Decl>(); 44 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 45 return DN->getQualifiedNameAsString(); 46 return ""; 47} 48 49Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 50 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 51} 52 53/// \brief If the identifier refers to a type name within this scope, 54/// return the declaration of that type. 55/// 56/// This routine performs ordinary name lookup of the identifier II 57/// within the given scope, with optional C++ scope specifier SS, to 58/// determine whether the name refers to a type. If so, returns an 59/// opaque pointer (actually a QualType) corresponding to that 60/// type. Otherwise, returns NULL. 61/// 62/// If name lookup results in an ambiguity, this routine will complain 63/// and then return NULL. 64Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 65 Scope *S, const CXXScopeSpec *SS, 66 bool isClassName) { 67 // C++ [temp.res]p3: 68 // A qualified-id that refers to a type and in which the 69 // nested-name-specifier depends on a template-parameter (14.6.2) 70 // shall be prefixed by the keyword typename to indicate that the 71 // qualified-id denotes a type, forming an 72 // elaborated-type-specifier (7.1.5.3). 73 // 74 // We therefore do not perform any name lookup if the result would 75 // refer to a member of an unknown specialization. 76 if (SS && isUnknownSpecialization(*SS)) { 77 if (!isClassName) 78 return 0; 79 80 // We know from the grammar that this name refers to a type, so build a 81 // TypenameType node to describe the type. 82 // FIXME: Record somewhere that this TypenameType node has no "typename" 83 // keyword associated with it. 84 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 85 II, SS->getRange()).getAsOpaquePtr(); 86 } 87 88 LookupResult Result 89 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 90 91 NamedDecl *IIDecl = 0; 92 switch (Result.getKind()) { 93 case LookupResult::NotFound: 94 case LookupResult::FoundOverloaded: 95 return 0; 96 97 case LookupResult::AmbiguousBaseSubobjectTypes: 98 case LookupResult::AmbiguousBaseSubobjects: 99 case LookupResult::AmbiguousReference: { 100 // Look to see if we have a type anywhere in the list of results. 101 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 102 Res != ResEnd; ++Res) { 103 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 104 if (!IIDecl || 105 (*Res)->getLocation().getRawEncoding() < 106 IIDecl->getLocation().getRawEncoding()) 107 IIDecl = *Res; 108 } 109 } 110 111 if (!IIDecl) { 112 // None of the entities we found is a type, so there is no way 113 // to even assume that the result is a type. In this case, don't 114 // complain about the ambiguity. The parser will either try to 115 // perform this lookup again (e.g., as an object name), which 116 // will produce the ambiguity, or will complain that it expected 117 // a type name. 118 Result.Destroy(); 119 return 0; 120 } 121 122 // We found a type within the ambiguous lookup; diagnose the 123 // ambiguity and then return that type. This might be the right 124 // answer, or it might not be, but it suppresses any attempt to 125 // perform the name lookup again. 126 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 127 break; 128 } 129 130 case LookupResult::Found: 131 IIDecl = Result.getAsDecl(); 132 break; 133 } 134 135 if (IIDecl) { 136 QualType T; 137 138 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 139 // Check whether we can use this type 140 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 141 142 if (getLangOptions().CPlusPlus) { 143 // C++ [temp.local]p2: 144 // Within the scope of a class template specialization or 145 // partial specialization, when the injected-class-name is 146 // not followed by a <, it is equivalent to the 147 // injected-class-name followed by the template-argument s 148 // of the class template specialization or partial 149 // specialization enclosed in <>. 150 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 151 if (RD->isInjectedClassName()) 152 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 153 T = Template->getInjectedClassNameType(Context); 154 } 155 156 if (T.isNull()) 157 T = Context.getTypeDeclType(TD); 158 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 159 // Check whether we can use this interface. 160 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 161 162 T = Context.getObjCInterfaceType(IDecl); 163 } else 164 return 0; 165 166 if (SS) 167 T = getQualifiedNameType(*SS, T); 168 169 return T.getAsOpaquePtr(); 170 } 171 172 return 0; 173} 174 175/// isTagName() - This method is called *for error recovery purposes only* 176/// to determine if the specified name is a valid tag name ("struct foo"). If 177/// so, this returns the TST for the tag corresponding to it (TST_enum, 178/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 179/// where the user forgot to specify the tag. 180DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 181 // Do a tag name lookup in this scope. 182 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 183 if (R.getKind() == LookupResult::Found) 184 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 185 switch (TD->getTagKind()) { 186 case TagDecl::TK_struct: return DeclSpec::TST_struct; 187 case TagDecl::TK_union: return DeclSpec::TST_union; 188 case TagDecl::TK_class: return DeclSpec::TST_class; 189 case TagDecl::TK_enum: return DeclSpec::TST_enum; 190 } 191 } 192 193 return DeclSpec::TST_unspecified; 194} 195 196 197// Determines the context to return to after temporarily entering a 198// context. This depends in an unnecessarily complicated way on the 199// exact ordering of callbacks from the parser. 200DeclContext *Sema::getContainingDC(DeclContext *DC) { 201 202 // Functions defined inline within classes aren't parsed until we've 203 // finished parsing the top-level class, so the top-level class is 204 // the context we'll need to return to. 205 if (isa<FunctionDecl>(DC)) { 206 DC = DC->getLexicalParent(); 207 208 // A function not defined within a class will always return to its 209 // lexical context. 210 if (!isa<CXXRecordDecl>(DC)) 211 return DC; 212 213 // A C++ inline method/friend is parsed *after* the topmost class 214 // it was declared in is fully parsed ("complete"); the topmost 215 // class is the context we need to return to. 216 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 217 DC = RD; 218 219 // Return the declaration context of the topmost class the inline method is 220 // declared in. 221 return DC; 222 } 223 224 if (isa<ObjCMethodDecl>(DC)) 225 return Context.getTranslationUnitDecl(); 226 227 return DC->getLexicalParent(); 228} 229 230void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 231 assert(getContainingDC(DC) == CurContext && 232 "The next DeclContext should be lexically contained in the current one."); 233 CurContext = DC; 234 S->setEntity(DC); 235} 236 237void Sema::PopDeclContext() { 238 assert(CurContext && "DeclContext imbalance!"); 239 240 CurContext = getContainingDC(CurContext); 241} 242 243/// EnterDeclaratorContext - Used when we must lookup names in the context 244/// of a declarator's nested name specifier. 245void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 246 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 247 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 248 CurContext = DC; 249 assert(CurContext && "No context?"); 250 S->setEntity(CurContext); 251} 252 253void Sema::ExitDeclaratorContext(Scope *S) { 254 S->setEntity(PreDeclaratorDC); 255 PreDeclaratorDC = 0; 256 257 // Reset CurContext to the nearest enclosing context. 258 while (!S->getEntity() && S->getParent()) 259 S = S->getParent(); 260 CurContext = static_cast<DeclContext*>(S->getEntity()); 261 assert(CurContext && "No context?"); 262} 263 264/// \brief Determine whether we allow overloading of the function 265/// PrevDecl with another declaration. 266/// 267/// This routine determines whether overloading is possible, not 268/// whether some new function is actually an overload. It will return 269/// true in C++ (where we can always provide overloads) or, as an 270/// extension, in C when the previous function is already an 271/// overloaded function declaration or has the "overloadable" 272/// attribute. 273static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 274 if (Context.getLangOptions().CPlusPlus) 275 return true; 276 277 if (isa<OverloadedFunctionDecl>(PrevDecl)) 278 return true; 279 280 return PrevDecl->getAttr<OverloadableAttr>() != 0; 281} 282 283/// Add this decl to the scope shadowed decl chains. 284void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 285 // Move up the scope chain until we find the nearest enclosing 286 // non-transparent context. The declaration will be introduced into this 287 // scope. 288 while (S->getEntity() && 289 ((DeclContext *)S->getEntity())->isTransparentContext()) 290 S = S->getParent(); 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 if (AddToContext) 296 CurContext->addDecl(D); 297 298 // Out-of-line function and variable definitions should not be pushed into 299 // scope. 300 if ((isa<FunctionTemplateDecl>(D) && 301 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 302 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 303 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 304 return; 305 306 S->AddDecl(DeclPtrTy::make(D)); 307 308 // C++ [basic.scope]p4: 309 // -- exactly one declaration shall declare a class name or 310 // enumeration name that is not a typedef name and the other 311 // declarations shall all refer to the same object or 312 // enumerator, or all refer to functions and function templates; 313 // in this case the class name or enumeration name is hidden. 314 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 315 // We are pushing the name of a tag (enum or class). 316 if (CurContext->getLookupContext() 317 == TD->getDeclContext()->getLookupContext()) { 318 // We're pushing the tag into the current context, which might 319 // require some reshuffling in the identifier resolver. 320 IdentifierResolver::iterator 321 I = IdResolver.begin(TD->getDeclName()), 322 IEnd = IdResolver.end(); 323 NamedDecl *ID = *I; 324 if (I != IEnd && isDeclInScope(ID, CurContext, S)) { 325 NamedDecl *PrevDecl = *I; 326 for (; I != IEnd && isDeclInScope(ID, CurContext, S); 327 PrevDecl = *I, ++I) { 328 if (TD->declarationReplaces(*I)) { 329 // This is a redeclaration. Remove it from the chain and 330 // break out, so that we'll add in the shadowed 331 // declaration. 332 S->RemoveDecl(DeclPtrTy::make(*I)); 333 if (PrevDecl == *I) { 334 IdResolver.RemoveDecl(*I); 335 IdResolver.AddDecl(TD); 336 return; 337 } else { 338 IdResolver.RemoveDecl(*I); 339 break; 340 } 341 } 342 } 343 344 // There is already a declaration with the same name in the same 345 // scope, which is not a tag declaration. It must be found 346 // before we find the new declaration, so insert the new 347 // declaration at the end of the chain. 348 IdResolver.AddShadowedDecl(TD, PrevDecl); 349 350 return; 351 } 352 } 353 } else if ((isa<FunctionDecl>(D) && 354 AllowOverloadingOfFunction(D, Context)) || 355 isa<FunctionTemplateDecl>(D)) { 356 // We are pushing the name of a function or function template, 357 // which might be an overloaded name. 358 IdentifierResolver::iterator Redecl 359 = std::find_if(IdResolver.begin(D->getDeclName()), 360 IdResolver.end(), 361 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 362 D)); 363 if (Redecl != IdResolver.end() && 364 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 365 // There is already a declaration of a function on our 366 // IdResolver chain. Replace it with this declaration. 367 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 368 IdResolver.RemoveDecl(*Redecl); 369 } 370 } else if (isa<ObjCInterfaceDecl>(D)) { 371 // We're pushing an Objective-C interface into the current 372 // context. If there is already an alias declaration, remove it first. 373 for (IdentifierResolver::iterator 374 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 375 I != IEnd; ++I) { 376 if (isa<ObjCCompatibleAliasDecl>(*I)) { 377 S->RemoveDecl(DeclPtrTy::make(*I)); 378 IdResolver.RemoveDecl(*I); 379 break; 380 } 381 } 382 } 383 384 IdResolver.AddDecl(D); 385} 386 387bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 388 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 389 // Look inside the overload set to determine if any of the declarations 390 // are in scope. (Possibly) build a new overload set containing only 391 // those declarations that are in scope. 392 OverloadedFunctionDecl *NewOvl = 0; 393 bool FoundInScope = false; 394 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 395 FEnd = Ovl->function_end(); 396 F != FEnd; ++F) { 397 NamedDecl *FD = F->get(); 398 if (!isDeclInScope(FD, Ctx, S)) { 399 if (!NewOvl && F != Ovl->function_begin()) { 400 NewOvl = OverloadedFunctionDecl::Create(Context, 401 F->get()->getDeclContext(), 402 F->get()->getDeclName()); 403 D = NewOvl; 404 for (OverloadedFunctionDecl::function_iterator 405 First = Ovl->function_begin(); 406 First != F; ++First) 407 NewOvl->addOverload(*First); 408 } 409 } else { 410 FoundInScope = true; 411 if (NewOvl) 412 NewOvl->addOverload(*F); 413 } 414 } 415 416 return FoundInScope; 417 } 418 419 return IdResolver.isDeclInScope(D, Ctx, Context, S); 420} 421 422void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 423 if (S->decl_empty()) return; 424 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 425 "Scope shouldn't contain decls!"); 426 427 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 428 I != E; ++I) { 429 Decl *TmpD = (*I).getAs<Decl>(); 430 assert(TmpD && "This decl didn't get pushed??"); 431 432 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 433 NamedDecl *D = cast<NamedDecl>(TmpD); 434 435 if (!D->getDeclName()) continue; 436 437 // Remove this name from our lexical scope. 438 IdResolver.RemoveDecl(D); 439 } 440} 441 442/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 443/// return 0 if one not found. 444ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 445 // The third "scope" argument is 0 since we aren't enabling lazy built-in 446 // creation from this context. 447 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 448 449 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 450} 451 452/// getNonFieldDeclScope - Retrieves the innermost scope, starting 453/// from S, where a non-field would be declared. This routine copes 454/// with the difference between C and C++ scoping rules in structs and 455/// unions. For example, the following code is well-formed in C but 456/// ill-formed in C++: 457/// @code 458/// struct S6 { 459/// enum { BAR } e; 460/// }; 461/// 462/// void test_S6() { 463/// struct S6 a; 464/// a.e = BAR; 465/// } 466/// @endcode 467/// For the declaration of BAR, this routine will return a different 468/// scope. The scope S will be the scope of the unnamed enumeration 469/// within S6. In C++, this routine will return the scope associated 470/// with S6, because the enumeration's scope is a transparent 471/// context but structures can contain non-field names. In C, this 472/// routine will return the translation unit scope, since the 473/// enumeration's scope is a transparent context and structures cannot 474/// contain non-field names. 475Scope *Sema::getNonFieldDeclScope(Scope *S) { 476 while (((S->getFlags() & Scope::DeclScope) == 0) || 477 (S->getEntity() && 478 ((DeclContext *)S->getEntity())->isTransparentContext()) || 479 (S->isClassScope() && !getLangOptions().CPlusPlus)) 480 S = S->getParent(); 481 return S; 482} 483 484void Sema::InitBuiltinVaListType() { 485 if (!Context.getBuiltinVaListType().isNull()) 486 return; 487 488 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 489 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 490 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 491 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 492} 493 494/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 495/// file scope. lazily create a decl for it. ForRedeclaration is true 496/// if we're creating this built-in in anticipation of redeclaring the 497/// built-in. 498NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 499 Scope *S, bool ForRedeclaration, 500 SourceLocation Loc) { 501 Builtin::ID BID = (Builtin::ID)bid; 502 503 if (Context.BuiltinInfo.hasVAListUse(BID)) 504 InitBuiltinVaListType(); 505 506 ASTContext::GetBuiltinTypeError Error; 507 QualType R = Context.GetBuiltinType(BID, Error); 508 switch (Error) { 509 case ASTContext::GE_None: 510 // Okay 511 break; 512 513 case ASTContext::GE_Missing_stdio: 514 if (ForRedeclaration) 515 Diag(Loc, diag::err_implicit_decl_requires_stdio) 516 << Context.BuiltinInfo.GetName(BID); 517 return 0; 518 519 case ASTContext::GE_Missing_setjmp: 520 if (ForRedeclaration) 521 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 522 << Context.BuiltinInfo.GetName(BID); 523 return 0; 524 } 525 526 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 527 Diag(Loc, diag::ext_implicit_lib_function_decl) 528 << Context.BuiltinInfo.GetName(BID) 529 << R; 530 if (Context.BuiltinInfo.getHeaderName(BID) && 531 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 532 != Diagnostic::Ignored) 533 Diag(Loc, diag::note_please_include_header) 534 << Context.BuiltinInfo.getHeaderName(BID) 535 << Context.BuiltinInfo.GetName(BID); 536 } 537 538 FunctionDecl *New = FunctionDecl::Create(Context, 539 Context.getTranslationUnitDecl(), 540 Loc, II, R, /*DInfo=*/0, 541 FunctionDecl::Extern, false, 542 /*hasPrototype=*/true); 543 New->setImplicit(); 544 545 // Create Decl objects for each parameter, adding them to the 546 // FunctionDecl. 547 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 548 llvm::SmallVector<ParmVarDecl*, 16> Params; 549 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 550 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 551 FT->getArgType(i), /*DInfo=*/0, 552 VarDecl::None, 0)); 553 New->setParams(Context, Params.data(), Params.size()); 554 } 555 556 AddKnownFunctionAttributes(New); 557 558 // TUScope is the translation-unit scope to insert this function into. 559 // FIXME: This is hideous. We need to teach PushOnScopeChains to 560 // relate Scopes to DeclContexts, and probably eliminate CurContext 561 // entirely, but we're not there yet. 562 DeclContext *SavedContext = CurContext; 563 CurContext = Context.getTranslationUnitDecl(); 564 PushOnScopeChains(New, TUScope); 565 CurContext = SavedContext; 566 return New; 567} 568 569/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 570/// same name and scope as a previous declaration 'Old'. Figure out 571/// how to resolve this situation, merging decls or emitting 572/// diagnostics as appropriate. If there was an error, set New to be invalid. 573/// 574void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 575 // If either decl is known invalid already, set the new one to be invalid and 576 // don't bother doing any merging checks. 577 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 578 return New->setInvalidDecl(); 579 580 // Allow multiple definitions for ObjC built-in typedefs. 581 // FIXME: Verify the underlying types are equivalent! 582 if (getLangOptions().ObjC1) { 583 const IdentifierInfo *TypeID = New->getIdentifier(); 584 switch (TypeID->getLength()) { 585 default: break; 586 case 2: 587 if (!TypeID->isStr("id")) 588 break; 589 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 590 // Install the built-in type for 'id', ignoring the current definition. 591 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 592 return; 593 case 5: 594 if (!TypeID->isStr("Class")) 595 break; 596 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 597 // Install the built-in type for 'Class', ignoring the current definition. 598 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 599 return; 600 case 3: 601 if (!TypeID->isStr("SEL")) 602 break; 603 Context.setObjCSelType(Context.getTypeDeclType(New)); 604 return; 605 case 8: 606 if (!TypeID->isStr("Protocol")) 607 break; 608 Context.setObjCProtoType(New->getUnderlyingType()); 609 return; 610 } 611 // Fall through - the typedef name was not a builtin type. 612 } 613 // Verify the old decl was also a type. 614 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 615 if (!Old) { 616 Diag(New->getLocation(), diag::err_redefinition_different_kind) 617 << New->getDeclName(); 618 if (OldD->getLocation().isValid()) 619 Diag(OldD->getLocation(), diag::note_previous_definition); 620 return New->setInvalidDecl(); 621 } 622 623 // Determine the "old" type we'll use for checking and diagnostics. 624 QualType OldType; 625 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 626 OldType = OldTypedef->getUnderlyingType(); 627 else 628 OldType = Context.getTypeDeclType(Old); 629 630 // If the typedef types are not identical, reject them in all languages and 631 // with any extensions enabled. 632 633 if (OldType != New->getUnderlyingType() && 634 Context.getCanonicalType(OldType) != 635 Context.getCanonicalType(New->getUnderlyingType())) { 636 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 637 << New->getUnderlyingType() << OldType; 638 if (Old->getLocation().isValid()) 639 Diag(Old->getLocation(), diag::note_previous_definition); 640 return New->setInvalidDecl(); 641 } 642 643 if (getLangOptions().Microsoft) 644 return; 645 646 // C++ [dcl.typedef]p2: 647 // In a given non-class scope, a typedef specifier can be used to 648 // redefine the name of any type declared in that scope to refer 649 // to the type to which it already refers. 650 if (getLangOptions().CPlusPlus) { 651 if (!isa<CXXRecordDecl>(CurContext)) 652 return; 653 Diag(New->getLocation(), diag::err_redefinition) 654 << New->getDeclName(); 655 Diag(Old->getLocation(), diag::note_previous_definition); 656 return New->setInvalidDecl(); 657 } 658 659 // If we have a redefinition of a typedef in C, emit a warning. This warning 660 // is normally mapped to an error, but can be controlled with 661 // -Wtypedef-redefinition. If either the original or the redefinition is 662 // in a system header, don't emit this for compatibility with GCC. 663 if (PP.getDiagnostics().getSuppressSystemWarnings() && 664 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 665 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 666 return; 667 668 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 669 << New->getDeclName(); 670 Diag(Old->getLocation(), diag::note_previous_definition); 671 return; 672} 673 674/// DeclhasAttr - returns true if decl Declaration already has the target 675/// attribute. 676static bool 677DeclHasAttr(const Decl *decl, const Attr *target) { 678 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 679 if (attr->getKind() == target->getKind()) 680 return true; 681 682 return false; 683} 684 685/// MergeAttributes - append attributes from the Old decl to the New one. 686static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 687 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 688 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 689 Attr *NewAttr = attr->clone(C); 690 NewAttr->setInherited(true); 691 New->addAttr(NewAttr); 692 } 693 } 694} 695 696/// Used in MergeFunctionDecl to keep track of function parameters in 697/// C. 698struct GNUCompatibleParamWarning { 699 ParmVarDecl *OldParm; 700 ParmVarDecl *NewParm; 701 QualType PromotedType; 702}; 703 704/// MergeFunctionDecl - We just parsed a function 'New' from 705/// declarator D which has the same name and scope as a previous 706/// declaration 'Old'. Figure out how to resolve this situation, 707/// merging decls or emitting diagnostics as appropriate. 708/// 709/// In C++, New and Old must be declarations that are not 710/// overloaded. Use IsOverload to determine whether New and Old are 711/// overloaded, and to select the Old declaration that New should be 712/// merged with. 713/// 714/// Returns true if there was an error, false otherwise. 715bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 716 assert(!isa<OverloadedFunctionDecl>(OldD) && 717 "Cannot merge with an overloaded function declaration"); 718 719 // Verify the old decl was also a function. 720 FunctionDecl *Old = 0; 721 if (FunctionTemplateDecl *OldFunctionTemplate 722 = dyn_cast<FunctionTemplateDecl>(OldD)) 723 Old = OldFunctionTemplate->getTemplatedDecl(); 724 else 725 Old = dyn_cast<FunctionDecl>(OldD); 726 if (!Old) { 727 Diag(New->getLocation(), diag::err_redefinition_different_kind) 728 << New->getDeclName(); 729 Diag(OldD->getLocation(), diag::note_previous_definition); 730 return true; 731 } 732 733 // Determine whether the previous declaration was a definition, 734 // implicit declaration, or a declaration. 735 diag::kind PrevDiag; 736 if (Old->isThisDeclarationADefinition()) 737 PrevDiag = diag::note_previous_definition; 738 else if (Old->isImplicit()) 739 PrevDiag = diag::note_previous_implicit_declaration; 740 else 741 PrevDiag = diag::note_previous_declaration; 742 743 QualType OldQType = Context.getCanonicalType(Old->getType()); 744 QualType NewQType = Context.getCanonicalType(New->getType()); 745 746 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 747 New->getStorageClass() == FunctionDecl::Static && 748 Old->getStorageClass() != FunctionDecl::Static) { 749 Diag(New->getLocation(), diag::err_static_non_static) 750 << New; 751 Diag(Old->getLocation(), PrevDiag); 752 return true; 753 } 754 755 if (getLangOptions().CPlusPlus) { 756 // (C++98 13.1p2): 757 // Certain function declarations cannot be overloaded: 758 // -- Function declarations that differ only in the return type 759 // cannot be overloaded. 760 QualType OldReturnType 761 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 762 QualType NewReturnType 763 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 764 if (OldReturnType != NewReturnType) { 765 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 766 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 767 return true; 768 } 769 770 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 771 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 772 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 773 NewMethod->getLexicalDeclContext()->isRecord()) { 774 // -- Member function declarations with the same name and the 775 // same parameter types cannot be overloaded if any of them 776 // is a static member function declaration. 777 if (OldMethod->isStatic() || NewMethod->isStatic()) { 778 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 779 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 780 return true; 781 } 782 783 // C++ [class.mem]p1: 784 // [...] A member shall not be declared twice in the 785 // member-specification, except that a nested class or member 786 // class template can be declared and then later defined. 787 unsigned NewDiag; 788 if (isa<CXXConstructorDecl>(OldMethod)) 789 NewDiag = diag::err_constructor_redeclared; 790 else if (isa<CXXDestructorDecl>(NewMethod)) 791 NewDiag = diag::err_destructor_redeclared; 792 else if (isa<CXXConversionDecl>(NewMethod)) 793 NewDiag = diag::err_conv_function_redeclared; 794 else 795 NewDiag = diag::err_member_redeclared; 796 797 Diag(New->getLocation(), NewDiag); 798 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 799 } 800 801 // (C++98 8.3.5p3): 802 // All declarations for a function shall agree exactly in both the 803 // return type and the parameter-type-list. 804 if (OldQType == NewQType) 805 return MergeCompatibleFunctionDecls(New, Old); 806 807 // Fall through for conflicting redeclarations and redefinitions. 808 } 809 810 // C: Function types need to be compatible, not identical. This handles 811 // duplicate function decls like "void f(int); void f(enum X);" properly. 812 if (!getLangOptions().CPlusPlus && 813 Context.typesAreCompatible(OldQType, NewQType)) { 814 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 815 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 816 const FunctionProtoType *OldProto = 0; 817 if (isa<FunctionNoProtoType>(NewFuncType) && 818 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 819 // The old declaration provided a function prototype, but the 820 // new declaration does not. Merge in the prototype. 821 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 822 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 823 OldProto->arg_type_end()); 824 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 825 ParamTypes.data(), ParamTypes.size(), 826 OldProto->isVariadic(), 827 OldProto->getTypeQuals()); 828 New->setType(NewQType); 829 New->setHasInheritedPrototype(); 830 831 // Synthesize a parameter for each argument type. 832 llvm::SmallVector<ParmVarDecl*, 16> Params; 833 for (FunctionProtoType::arg_type_iterator 834 ParamType = OldProto->arg_type_begin(), 835 ParamEnd = OldProto->arg_type_end(); 836 ParamType != ParamEnd; ++ParamType) { 837 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 838 SourceLocation(), 0, 839 *ParamType, /*DInfo=*/0, 840 VarDecl::None, 0); 841 Param->setImplicit(); 842 Params.push_back(Param); 843 } 844 845 New->setParams(Context, Params.data(), Params.size()); 846 } 847 848 return MergeCompatibleFunctionDecls(New, Old); 849 } 850 851 // GNU C permits a K&R definition to follow a prototype declaration 852 // if the declared types of the parameters in the K&R definition 853 // match the types in the prototype declaration, even when the 854 // promoted types of the parameters from the K&R definition differ 855 // from the types in the prototype. GCC then keeps the types from 856 // the prototype. 857 // 858 // If a variadic prototype is followed by a non-variadic K&R definition, 859 // the K&R definition becomes variadic. This is sort of an edge case, but 860 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 861 // C99 6.9.1p8. 862 if (!getLangOptions().CPlusPlus && 863 Old->hasPrototype() && !New->hasPrototype() && 864 New->getType()->getAs<FunctionProtoType>() && 865 Old->getNumParams() == New->getNumParams()) { 866 llvm::SmallVector<QualType, 16> ArgTypes; 867 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 868 const FunctionProtoType *OldProto 869 = Old->getType()->getAs<FunctionProtoType>(); 870 const FunctionProtoType *NewProto 871 = New->getType()->getAs<FunctionProtoType>(); 872 873 // Determine whether this is the GNU C extension. 874 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 875 NewProto->getResultType()); 876 bool LooseCompatible = !MergedReturn.isNull(); 877 for (unsigned Idx = 0, End = Old->getNumParams(); 878 LooseCompatible && Idx != End; ++Idx) { 879 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 880 ParmVarDecl *NewParm = New->getParamDecl(Idx); 881 if (Context.typesAreCompatible(OldParm->getType(), 882 NewProto->getArgType(Idx))) { 883 ArgTypes.push_back(NewParm->getType()); 884 } else if (Context.typesAreCompatible(OldParm->getType(), 885 NewParm->getType())) { 886 GNUCompatibleParamWarning Warn 887 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 888 Warnings.push_back(Warn); 889 ArgTypes.push_back(NewParm->getType()); 890 } else 891 LooseCompatible = false; 892 } 893 894 if (LooseCompatible) { 895 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 896 Diag(Warnings[Warn].NewParm->getLocation(), 897 diag::ext_param_promoted_not_compatible_with_prototype) 898 << Warnings[Warn].PromotedType 899 << Warnings[Warn].OldParm->getType(); 900 Diag(Warnings[Warn].OldParm->getLocation(), 901 diag::note_previous_declaration); 902 } 903 904 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 905 ArgTypes.size(), 906 OldProto->isVariadic(), 0)); 907 return MergeCompatibleFunctionDecls(New, Old); 908 } 909 910 // Fall through to diagnose conflicting types. 911 } 912 913 // A function that has already been declared has been redeclared or defined 914 // with a different type- show appropriate diagnostic 915 if (unsigned BuiltinID = Old->getBuiltinID()) { 916 // The user has declared a builtin function with an incompatible 917 // signature. 918 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 919 // The function the user is redeclaring is a library-defined 920 // function like 'malloc' or 'printf'. Warn about the 921 // redeclaration, then pretend that we don't know about this 922 // library built-in. 923 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 924 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 925 << Old << Old->getType(); 926 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 927 Old->setInvalidDecl(); 928 return false; 929 } 930 931 PrevDiag = diag::note_previous_builtin_declaration; 932 } 933 934 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 935 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 936 return true; 937} 938 939/// \brief Completes the merge of two function declarations that are 940/// known to be compatible. 941/// 942/// This routine handles the merging of attributes and other 943/// properties of function declarations form the old declaration to 944/// the new declaration, once we know that New is in fact a 945/// redeclaration of Old. 946/// 947/// \returns false 948bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 949 // Merge the attributes 950 MergeAttributes(New, Old, Context); 951 952 // Merge the storage class. 953 if (Old->getStorageClass() != FunctionDecl::Extern && 954 Old->getStorageClass() != FunctionDecl::None) 955 New->setStorageClass(Old->getStorageClass()); 956 957 // Merge "pure" flag. 958 if (Old->isPure()) 959 New->setPure(); 960 961 // Merge the "deleted" flag. 962 if (Old->isDeleted()) 963 New->setDeleted(); 964 965 if (getLangOptions().CPlusPlus) 966 return MergeCXXFunctionDecl(New, Old); 967 968 return false; 969} 970 971/// MergeVarDecl - We just parsed a variable 'New' which has the same name 972/// and scope as a previous declaration 'Old'. Figure out how to resolve this 973/// situation, merging decls or emitting diagnostics as appropriate. 974/// 975/// Tentative definition rules (C99 6.9.2p2) are checked by 976/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 977/// definitions here, since the initializer hasn't been attached. 978/// 979void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 980 // If either decl is invalid, make sure the new one is marked invalid and 981 // don't do any other checking. 982 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 983 return New->setInvalidDecl(); 984 985 // Verify the old decl was also a variable. 986 VarDecl *Old = dyn_cast<VarDecl>(OldD); 987 if (!Old) { 988 Diag(New->getLocation(), diag::err_redefinition_different_kind) 989 << New->getDeclName(); 990 Diag(OldD->getLocation(), diag::note_previous_definition); 991 return New->setInvalidDecl(); 992 } 993 994 MergeAttributes(New, Old, Context); 995 996 // Merge the types 997 QualType MergedT; 998 if (getLangOptions().CPlusPlus) { 999 if (Context.hasSameType(New->getType(), Old->getType())) 1000 MergedT = New->getType(); 1001 // C++ [basic.types]p7: 1002 // [...] The declared type of an array object might be an array of 1003 // unknown size and therefore be incomplete at one point in a 1004 // translation unit and complete later on; [...] 1005 else if (Old->getType()->isIncompleteArrayType() && 1006 New->getType()->isArrayType()) { 1007 CanQual<ArrayType> OldArray 1008 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1009 CanQual<ArrayType> NewArray 1010 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1011 if (OldArray->getElementType() == NewArray->getElementType()) 1012 MergedT = New->getType(); 1013 } 1014 } else { 1015 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1016 } 1017 if (MergedT.isNull()) { 1018 Diag(New->getLocation(), diag::err_redefinition_different_type) 1019 << New->getDeclName(); 1020 Diag(Old->getLocation(), diag::note_previous_definition); 1021 return New->setInvalidDecl(); 1022 } 1023 New->setType(MergedT); 1024 1025 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1026 if (New->getStorageClass() == VarDecl::Static && 1027 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1028 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1029 Diag(Old->getLocation(), diag::note_previous_definition); 1030 return New->setInvalidDecl(); 1031 } 1032 // C99 6.2.2p4: 1033 // For an identifier declared with the storage-class specifier 1034 // extern in a scope in which a prior declaration of that 1035 // identifier is visible,23) if the prior declaration specifies 1036 // internal or external linkage, the linkage of the identifier at 1037 // the later declaration is the same as the linkage specified at 1038 // the prior declaration. If no prior declaration is visible, or 1039 // if the prior declaration specifies no linkage, then the 1040 // identifier has external linkage. 1041 if (New->hasExternalStorage() && Old->hasLinkage()) 1042 /* Okay */; 1043 else if (New->getStorageClass() != VarDecl::Static && 1044 Old->getStorageClass() == VarDecl::Static) { 1045 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1046 Diag(Old->getLocation(), diag::note_previous_definition); 1047 return New->setInvalidDecl(); 1048 } 1049 1050 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1051 1052 // FIXME: The test for external storage here seems wrong? We still 1053 // need to check for mismatches. 1054 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1055 // Don't complain about out-of-line definitions of static members. 1056 !(Old->getLexicalDeclContext()->isRecord() && 1057 !New->getLexicalDeclContext()->isRecord())) { 1058 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1059 Diag(Old->getLocation(), diag::note_previous_definition); 1060 return New->setInvalidDecl(); 1061 } 1062 1063 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1064 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1065 Diag(Old->getLocation(), diag::note_previous_definition); 1066 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1067 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1068 Diag(Old->getLocation(), diag::note_previous_definition); 1069 } 1070 1071 // Keep a chain of previous declarations. 1072 New->setPreviousDeclaration(Old); 1073} 1074 1075/// CheckFallThrough - Check that we don't fall off the end of a 1076/// Statement that should return a value. 1077/// 1078/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1079/// MaybeFallThrough iff we might or might not fall off the end and 1080/// NeverFallThrough iff we never fall off the end of the statement. We assume 1081/// that functions not marked noreturn will return. 1082Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1083 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1084 1085 // FIXME: They should never return 0, fix that, delete this code. 1086 if (cfg == 0) 1087 return NeverFallThrough; 1088 // The CFG leaves in dead things, and we don't want to dead code paths to 1089 // confuse us, so we mark all live things first. 1090 std::queue<CFGBlock*> workq; 1091 llvm::BitVector live(cfg->getNumBlockIDs()); 1092 // Prep work queue 1093 workq.push(&cfg->getEntry()); 1094 // Solve 1095 while (!workq.empty()) { 1096 CFGBlock *item = workq.front(); 1097 workq.pop(); 1098 live.set(item->getBlockID()); 1099 for (CFGBlock::succ_iterator I=item->succ_begin(), 1100 E=item->succ_end(); 1101 I != E; 1102 ++I) { 1103 if ((*I) && !live[(*I)->getBlockID()]) { 1104 live.set((*I)->getBlockID()); 1105 workq.push(*I); 1106 } 1107 } 1108 } 1109 1110 // Now we know what is live, we check the live precessors of the exit block 1111 // and look for fall through paths, being careful to ignore normal returns, 1112 // and exceptional paths. 1113 bool HasLiveReturn = false; 1114 bool HasFakeEdge = false; 1115 bool HasPlainEdge = false; 1116 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1117 E = cfg->getExit().pred_end(); 1118 I != E; 1119 ++I) { 1120 CFGBlock& B = **I; 1121 if (!live[B.getBlockID()]) 1122 continue; 1123 if (B.size() == 0) { 1124 // A labeled empty statement, or the entry block... 1125 HasPlainEdge = true; 1126 continue; 1127 } 1128 Stmt *S = B[B.size()-1]; 1129 if (isa<ReturnStmt>(S)) { 1130 HasLiveReturn = true; 1131 continue; 1132 } 1133 if (isa<ObjCAtThrowStmt>(S)) { 1134 HasFakeEdge = true; 1135 continue; 1136 } 1137 if (isa<CXXThrowExpr>(S)) { 1138 HasFakeEdge = true; 1139 continue; 1140 } 1141 bool NoReturnEdge = false; 1142 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1143 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1144 if (CEE->getType().getNoReturnAttr()) { 1145 NoReturnEdge = true; 1146 HasFakeEdge = true; 1147 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1148 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1149 if (FD->hasAttr<NoReturnAttr>()) { 1150 NoReturnEdge = true; 1151 HasFakeEdge = true; 1152 } 1153 } 1154 } 1155 } 1156 // FIXME: Add noreturn message sends. 1157 if (NoReturnEdge == false) 1158 HasPlainEdge = true; 1159 } 1160 if (!HasPlainEdge) 1161 return NeverFallThrough; 1162 if (HasFakeEdge || HasLiveReturn) 1163 return MaybeFallThrough; 1164 // This says AlwaysFallThrough for calls to functions that are not marked 1165 // noreturn, that don't return. If people would like this warning to be more 1166 // accurate, such functions should be marked as noreturn. 1167 return AlwaysFallThrough; 1168} 1169 1170/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1171/// function that should return a value. Check that we don't fall off the end 1172/// of a noreturn function. We assume that functions and blocks not marked 1173/// noreturn will return. 1174void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1175 // FIXME: Would be nice if we had a better way to control cascading errors, 1176 // but for now, avoid them. The problem is that when Parse sees: 1177 // int foo() { return a; } 1178 // The return is eaten and the Sema code sees just: 1179 // int foo() { } 1180 // which this code would then warn about. 1181 if (getDiagnostics().hasErrorOccurred()) 1182 return; 1183 bool ReturnsVoid = false; 1184 bool HasNoReturn = false; 1185 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1186 // If the result type of the function is a dependent type, we don't know 1187 // whether it will be void or not, so don't 1188 if (FD->getResultType()->isDependentType()) 1189 return; 1190 if (FD->getResultType()->isVoidType()) 1191 ReturnsVoid = true; 1192 if (FD->hasAttr<NoReturnAttr>()) 1193 HasNoReturn = true; 1194 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1195 if (MD->getResultType()->isVoidType()) 1196 ReturnsVoid = true; 1197 if (MD->hasAttr<NoReturnAttr>()) 1198 HasNoReturn = true; 1199 } 1200 1201 // Short circuit for compilation speed. 1202 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1203 == Diagnostic::Ignored || ReturnsVoid) 1204 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1205 == Diagnostic::Ignored || !HasNoReturn) 1206 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1207 == Diagnostic::Ignored || !ReturnsVoid)) 1208 return; 1209 // FIXME: Function try block 1210 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1211 switch (CheckFallThrough(Body)) { 1212 case MaybeFallThrough: 1213 if (HasNoReturn) 1214 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1215 else if (!ReturnsVoid) 1216 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1217 break; 1218 case AlwaysFallThrough: 1219 if (HasNoReturn) 1220 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1221 else if (!ReturnsVoid) 1222 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1223 break; 1224 case NeverFallThrough: 1225 if (ReturnsVoid) 1226 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1227 break; 1228 } 1229 } 1230} 1231 1232/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1233/// that should return a value. Check that we don't fall off the end of a 1234/// noreturn block. We assume that functions and blocks not marked noreturn 1235/// will return. 1236void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1237 // FIXME: Would be nice if we had a better way to control cascading errors, 1238 // but for now, avoid them. The problem is that when Parse sees: 1239 // int foo() { return a; } 1240 // The return is eaten and the Sema code sees just: 1241 // int foo() { } 1242 // which this code would then warn about. 1243 if (getDiagnostics().hasErrorOccurred()) 1244 return; 1245 bool ReturnsVoid = false; 1246 bool HasNoReturn = false; 1247 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1248 if (FT->getResultType()->isVoidType()) 1249 ReturnsVoid = true; 1250 if (FT->getNoReturnAttr()) 1251 HasNoReturn = true; 1252 } 1253 1254 // Short circuit for compilation speed. 1255 if (ReturnsVoid 1256 && !HasNoReturn 1257 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1258 == Diagnostic::Ignored || !ReturnsVoid)) 1259 return; 1260 // FIXME: Funtion try block 1261 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1262 switch (CheckFallThrough(Body)) { 1263 case MaybeFallThrough: 1264 if (HasNoReturn) 1265 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1266 else if (!ReturnsVoid) 1267 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1268 break; 1269 case AlwaysFallThrough: 1270 if (HasNoReturn) 1271 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1272 else if (!ReturnsVoid) 1273 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1274 break; 1275 case NeverFallThrough: 1276 if (ReturnsVoid) 1277 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1278 break; 1279 } 1280 } 1281} 1282 1283/// CheckParmsForFunctionDef - Check that the parameters of the given 1284/// function are appropriate for the definition of a function. This 1285/// takes care of any checks that cannot be performed on the 1286/// declaration itself, e.g., that the types of each of the function 1287/// parameters are complete. 1288bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1289 bool HasInvalidParm = false; 1290 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1291 ParmVarDecl *Param = FD->getParamDecl(p); 1292 1293 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1294 // function declarator that is part of a function definition of 1295 // that function shall not have incomplete type. 1296 // 1297 // This is also C++ [dcl.fct]p6. 1298 if (!Param->isInvalidDecl() && 1299 RequireCompleteType(Param->getLocation(), Param->getType(), 1300 diag::err_typecheck_decl_incomplete_type)) { 1301 Param->setInvalidDecl(); 1302 HasInvalidParm = true; 1303 } 1304 1305 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1306 // declaration of each parameter shall include an identifier. 1307 if (Param->getIdentifier() == 0 && 1308 !Param->isImplicit() && 1309 !getLangOptions().CPlusPlus) 1310 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1311 } 1312 1313 return HasInvalidParm; 1314} 1315 1316/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1317/// no declarator (e.g. "struct foo;") is parsed. 1318Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1319 // FIXME: Error on auto/register at file scope 1320 // FIXME: Error on inline/virtual/explicit 1321 // FIXME: Error on invalid restrict 1322 // FIXME: Warn on useless __thread 1323 // FIXME: Warn on useless const/volatile 1324 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1325 // FIXME: Warn on useless attributes 1326 Decl *TagD = 0; 1327 TagDecl *Tag = 0; 1328 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1329 DS.getTypeSpecType() == DeclSpec::TST_struct || 1330 DS.getTypeSpecType() == DeclSpec::TST_union || 1331 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1332 TagD = static_cast<Decl *>(DS.getTypeRep()); 1333 1334 if (!TagD) // We probably had an error 1335 return DeclPtrTy(); 1336 1337 // Note that the above type specs guarantee that the 1338 // type rep is a Decl, whereas in many of the others 1339 // it's a Type. 1340 Tag = dyn_cast<TagDecl>(TagD); 1341 } 1342 1343 if (DS.isFriendSpecified()) { 1344 // If we're dealing with a class template decl, assume that the 1345 // template routines are handling it. 1346 if (TagD && isa<ClassTemplateDecl>(TagD)) 1347 return DeclPtrTy(); 1348 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1349 } 1350 1351 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1352 if (!Record->getDeclName() && Record->isDefinition() && 1353 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1354 if (getLangOptions().CPlusPlus || 1355 Record->getDeclContext()->isRecord()) 1356 return BuildAnonymousStructOrUnion(S, DS, Record); 1357 1358 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1359 << DS.getSourceRange(); 1360 } 1361 1362 // Microsoft allows unnamed struct/union fields. Don't complain 1363 // about them. 1364 // FIXME: Should we support Microsoft's extensions in this area? 1365 if (Record->getDeclName() && getLangOptions().Microsoft) 1366 return DeclPtrTy::make(Tag); 1367 } 1368 1369 if (!DS.isMissingDeclaratorOk() && 1370 DS.getTypeSpecType() != DeclSpec::TST_error) { 1371 // Warn about typedefs of enums without names, since this is an 1372 // extension in both Microsoft an GNU. 1373 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1374 Tag && isa<EnumDecl>(Tag)) { 1375 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1376 << DS.getSourceRange(); 1377 return DeclPtrTy::make(Tag); 1378 } 1379 1380 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1381 << DS.getSourceRange(); 1382 return DeclPtrTy(); 1383 } 1384 1385 return DeclPtrTy::make(Tag); 1386} 1387 1388/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1389/// anonymous struct or union AnonRecord into the owning context Owner 1390/// and scope S. This routine will be invoked just after we realize 1391/// that an unnamed union or struct is actually an anonymous union or 1392/// struct, e.g., 1393/// 1394/// @code 1395/// union { 1396/// int i; 1397/// float f; 1398/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1399/// // f into the surrounding scope.x 1400/// @endcode 1401/// 1402/// This routine is recursive, injecting the names of nested anonymous 1403/// structs/unions into the owning context and scope as well. 1404bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1405 RecordDecl *AnonRecord) { 1406 bool Invalid = false; 1407 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1408 FEnd = AnonRecord->field_end(); 1409 F != FEnd; ++F) { 1410 if ((*F)->getDeclName()) { 1411 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1412 LookupOrdinaryName, true); 1413 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1414 // C++ [class.union]p2: 1415 // The names of the members of an anonymous union shall be 1416 // distinct from the names of any other entity in the 1417 // scope in which the anonymous union is declared. 1418 unsigned diagKind 1419 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1420 : diag::err_anonymous_struct_member_redecl; 1421 Diag((*F)->getLocation(), diagKind) 1422 << (*F)->getDeclName(); 1423 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1424 Invalid = true; 1425 } else { 1426 // C++ [class.union]p2: 1427 // For the purpose of name lookup, after the anonymous union 1428 // definition, the members of the anonymous union are 1429 // considered to have been defined in the scope in which the 1430 // anonymous union is declared. 1431 Owner->makeDeclVisibleInContext(*F); 1432 S->AddDecl(DeclPtrTy::make(*F)); 1433 IdResolver.AddDecl(*F); 1434 } 1435 } else if (const RecordType *InnerRecordType 1436 = (*F)->getType()->getAs<RecordType>()) { 1437 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1438 if (InnerRecord->isAnonymousStructOrUnion()) 1439 Invalid = Invalid || 1440 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1441 } 1442 } 1443 1444 return Invalid; 1445} 1446 1447/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1448/// anonymous structure or union. Anonymous unions are a C++ feature 1449/// (C++ [class.union]) and a GNU C extension; anonymous structures 1450/// are a GNU C and GNU C++ extension. 1451Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1452 RecordDecl *Record) { 1453 DeclContext *Owner = Record->getDeclContext(); 1454 1455 // Diagnose whether this anonymous struct/union is an extension. 1456 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1457 Diag(Record->getLocation(), diag::ext_anonymous_union); 1458 else if (!Record->isUnion()) 1459 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1460 1461 // C and C++ require different kinds of checks for anonymous 1462 // structs/unions. 1463 bool Invalid = false; 1464 if (getLangOptions().CPlusPlus) { 1465 const char* PrevSpec = 0; 1466 unsigned DiagID; 1467 // C++ [class.union]p3: 1468 // Anonymous unions declared in a named namespace or in the 1469 // global namespace shall be declared static. 1470 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1471 (isa<TranslationUnitDecl>(Owner) || 1472 (isa<NamespaceDecl>(Owner) && 1473 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1474 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1475 Invalid = true; 1476 1477 // Recover by adding 'static'. 1478 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1479 PrevSpec, DiagID); 1480 } 1481 // C++ [class.union]p3: 1482 // A storage class is not allowed in a declaration of an 1483 // anonymous union in a class scope. 1484 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1485 isa<RecordDecl>(Owner)) { 1486 Diag(DS.getStorageClassSpecLoc(), 1487 diag::err_anonymous_union_with_storage_spec); 1488 Invalid = true; 1489 1490 // Recover by removing the storage specifier. 1491 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1492 PrevSpec, DiagID); 1493 } 1494 1495 // C++ [class.union]p2: 1496 // The member-specification of an anonymous union shall only 1497 // define non-static data members. [Note: nested types and 1498 // functions cannot be declared within an anonymous union. ] 1499 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1500 MemEnd = Record->decls_end(); 1501 Mem != MemEnd; ++Mem) { 1502 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1503 // C++ [class.union]p3: 1504 // An anonymous union shall not have private or protected 1505 // members (clause 11). 1506 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1507 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1508 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1509 Invalid = true; 1510 } 1511 } else if ((*Mem)->isImplicit()) { 1512 // Any implicit members are fine. 1513 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1514 // This is a type that showed up in an 1515 // elaborated-type-specifier inside the anonymous struct or 1516 // union, but which actually declares a type outside of the 1517 // anonymous struct or union. It's okay. 1518 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1519 if (!MemRecord->isAnonymousStructOrUnion() && 1520 MemRecord->getDeclName()) { 1521 // This is a nested type declaration. 1522 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1523 << (int)Record->isUnion(); 1524 Invalid = true; 1525 } 1526 } else { 1527 // We have something that isn't a non-static data 1528 // member. Complain about it. 1529 unsigned DK = diag::err_anonymous_record_bad_member; 1530 if (isa<TypeDecl>(*Mem)) 1531 DK = diag::err_anonymous_record_with_type; 1532 else if (isa<FunctionDecl>(*Mem)) 1533 DK = diag::err_anonymous_record_with_function; 1534 else if (isa<VarDecl>(*Mem)) 1535 DK = diag::err_anonymous_record_with_static; 1536 Diag((*Mem)->getLocation(), DK) 1537 << (int)Record->isUnion(); 1538 Invalid = true; 1539 } 1540 } 1541 } 1542 1543 if (!Record->isUnion() && !Owner->isRecord()) { 1544 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1545 << (int)getLangOptions().CPlusPlus; 1546 Invalid = true; 1547 } 1548 1549 // Create a declaration for this anonymous struct/union. 1550 NamedDecl *Anon = 0; 1551 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1552 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1553 /*IdentifierInfo=*/0, 1554 Context.getTypeDeclType(Record), 1555 // FIXME: Type source info. 1556 /*DInfo=*/0, 1557 /*BitWidth=*/0, /*Mutable=*/false); 1558 Anon->setAccess(AS_public); 1559 if (getLangOptions().CPlusPlus) 1560 FieldCollector->Add(cast<FieldDecl>(Anon)); 1561 } else { 1562 VarDecl::StorageClass SC; 1563 switch (DS.getStorageClassSpec()) { 1564 default: assert(0 && "Unknown storage class!"); 1565 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1566 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1567 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1568 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1569 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1570 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1571 case DeclSpec::SCS_mutable: 1572 // mutable can only appear on non-static class members, so it's always 1573 // an error here 1574 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1575 Invalid = true; 1576 SC = VarDecl::None; 1577 break; 1578 } 1579 1580 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1581 /*IdentifierInfo=*/0, 1582 Context.getTypeDeclType(Record), 1583 // FIXME: Type source info. 1584 /*DInfo=*/0, 1585 SC); 1586 } 1587 Anon->setImplicit(); 1588 1589 // Add the anonymous struct/union object to the current 1590 // context. We'll be referencing this object when we refer to one of 1591 // its members. 1592 Owner->addDecl(Anon); 1593 1594 // Inject the members of the anonymous struct/union into the owning 1595 // context and into the identifier resolver chain for name lookup 1596 // purposes. 1597 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1598 Invalid = true; 1599 1600 // Mark this as an anonymous struct/union type. Note that we do not 1601 // do this until after we have already checked and injected the 1602 // members of this anonymous struct/union type, because otherwise 1603 // the members could be injected twice: once by DeclContext when it 1604 // builds its lookup table, and once by 1605 // InjectAnonymousStructOrUnionMembers. 1606 Record->setAnonymousStructOrUnion(true); 1607 1608 if (Invalid) 1609 Anon->setInvalidDecl(); 1610 1611 return DeclPtrTy::make(Anon); 1612} 1613 1614 1615/// GetNameForDeclarator - Determine the full declaration name for the 1616/// given Declarator. 1617DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1618 switch (D.getKind()) { 1619 case Declarator::DK_Abstract: 1620 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1621 return DeclarationName(); 1622 1623 case Declarator::DK_Normal: 1624 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1625 return DeclarationName(D.getIdentifier()); 1626 1627 case Declarator::DK_Constructor: { 1628 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1629 return Context.DeclarationNames.getCXXConstructorName( 1630 Context.getCanonicalType(Ty)); 1631 } 1632 1633 case Declarator::DK_Destructor: { 1634 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1635 return Context.DeclarationNames.getCXXDestructorName( 1636 Context.getCanonicalType(Ty)); 1637 } 1638 1639 case Declarator::DK_Conversion: { 1640 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1641 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1642 return Context.DeclarationNames.getCXXConversionFunctionName( 1643 Context.getCanonicalType(Ty)); 1644 } 1645 1646 case Declarator::DK_Operator: 1647 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1648 return Context.DeclarationNames.getCXXOperatorName( 1649 D.getOverloadedOperator()); 1650 1651 case Declarator::DK_TemplateId: { 1652 TemplateName Name 1653 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1654 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1655 return Template->getDeclName(); 1656 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1657 return Ovl->getDeclName(); 1658 1659 return DeclarationName(); 1660 } 1661 } 1662 1663 assert(false && "Unknown name kind"); 1664 return DeclarationName(); 1665} 1666 1667/// isNearlyMatchingFunction - Determine whether the C++ functions 1668/// Declaration and Definition are "nearly" matching. This heuristic 1669/// is used to improve diagnostics in the case where an out-of-line 1670/// function definition doesn't match any declaration within 1671/// the class or namespace. 1672static bool isNearlyMatchingFunction(ASTContext &Context, 1673 FunctionDecl *Declaration, 1674 FunctionDecl *Definition) { 1675 if (Declaration->param_size() != Definition->param_size()) 1676 return false; 1677 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1678 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1679 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1680 1681 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1682 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1683 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1684 return false; 1685 } 1686 1687 return true; 1688} 1689 1690Sema::DeclPtrTy 1691Sema::HandleDeclarator(Scope *S, Declarator &D, 1692 MultiTemplateParamsArg TemplateParamLists, 1693 bool IsFunctionDefinition) { 1694 DeclarationName Name = GetNameForDeclarator(D); 1695 1696 // All of these full declarators require an identifier. If it doesn't have 1697 // one, the ParsedFreeStandingDeclSpec action should be used. 1698 if (!Name) { 1699 if (!D.isInvalidType()) // Reject this if we think it is valid. 1700 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1701 diag::err_declarator_need_ident) 1702 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1703 return DeclPtrTy(); 1704 } 1705 1706 // The scope passed in may not be a decl scope. Zip up the scope tree until 1707 // we find one that is. 1708 while ((S->getFlags() & Scope::DeclScope) == 0 || 1709 (S->getFlags() & Scope::TemplateParamScope) != 0) 1710 S = S->getParent(); 1711 1712 // If this is an out-of-line definition of a member of a class template 1713 // or class template partial specialization, we may need to rebuild the 1714 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1715 // for more information. 1716 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1717 // handle expressions properly. 1718 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1719 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1720 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1721 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1722 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1723 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1724 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1725 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1726 // FIXME: Preserve type source info. 1727 QualType T = GetTypeFromParser(DS.getTypeRep()); 1728 EnterDeclaratorContext(S, DC); 1729 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1730 ExitDeclaratorContext(S); 1731 if (T.isNull()) 1732 return DeclPtrTy(); 1733 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1734 } 1735 } 1736 1737 DeclContext *DC; 1738 NamedDecl *PrevDecl; 1739 NamedDecl *New; 1740 1741 DeclaratorInfo *DInfo = 0; 1742 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1743 1744 // See if this is a redefinition of a variable in the same scope. 1745 if (D.getCXXScopeSpec().isInvalid()) { 1746 DC = CurContext; 1747 PrevDecl = 0; 1748 D.setInvalidType(); 1749 } else if (!D.getCXXScopeSpec().isSet()) { 1750 LookupNameKind NameKind = LookupOrdinaryName; 1751 1752 // If the declaration we're planning to build will be a function 1753 // or object with linkage, then look for another declaration with 1754 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1755 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1756 /* Do nothing*/; 1757 else if (R->isFunctionType()) { 1758 if (CurContext->isFunctionOrMethod() || 1759 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1760 NameKind = LookupRedeclarationWithLinkage; 1761 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1762 NameKind = LookupRedeclarationWithLinkage; 1763 else if (CurContext->getLookupContext()->isTranslationUnit() && 1764 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1765 NameKind = LookupRedeclarationWithLinkage; 1766 1767 DC = CurContext; 1768 PrevDecl = LookupName(S, Name, NameKind, true, 1769 NameKind == LookupRedeclarationWithLinkage, 1770 D.getIdentifierLoc()); 1771 } else { // Something like "int foo::x;" 1772 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1773 1774 if (!DC) { 1775 // If we could not compute the declaration context, it's because the 1776 // declaration context is dependent but does not refer to a class, 1777 // class template, or class template partial specialization. Complain 1778 // and return early, to avoid the coming semantic disaster. 1779 Diag(D.getIdentifierLoc(), 1780 diag::err_template_qualified_declarator_no_match) 1781 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1782 << D.getCXXScopeSpec().getRange(); 1783 return DeclPtrTy(); 1784 } 1785 1786 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1787 1788 // C++ 7.3.1.2p2: 1789 // Members (including explicit specializations of templates) of a named 1790 // namespace can also be defined outside that namespace by explicit 1791 // qualification of the name being defined, provided that the entity being 1792 // defined was already declared in the namespace and the definition appears 1793 // after the point of declaration in a namespace that encloses the 1794 // declarations namespace. 1795 // 1796 // Note that we only check the context at this point. We don't yet 1797 // have enough information to make sure that PrevDecl is actually 1798 // the declaration we want to match. For example, given: 1799 // 1800 // class X { 1801 // void f(); 1802 // void f(float); 1803 // }; 1804 // 1805 // void X::f(int) { } // ill-formed 1806 // 1807 // In this case, PrevDecl will point to the overload set 1808 // containing the two f's declared in X, but neither of them 1809 // matches. 1810 1811 // First check whether we named the global scope. 1812 if (isa<TranslationUnitDecl>(DC)) { 1813 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1814 << Name << D.getCXXScopeSpec().getRange(); 1815 } else if (!CurContext->Encloses(DC)) { 1816 // The qualifying scope doesn't enclose the original declaration. 1817 // Emit diagnostic based on current scope. 1818 SourceLocation L = D.getIdentifierLoc(); 1819 SourceRange R = D.getCXXScopeSpec().getRange(); 1820 if (isa<FunctionDecl>(CurContext)) 1821 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1822 else 1823 Diag(L, diag::err_invalid_declarator_scope) 1824 << Name << cast<NamedDecl>(DC) << R; 1825 D.setInvalidType(); 1826 } 1827 } 1828 1829 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1830 // Maybe we will complain about the shadowed template parameter. 1831 if (!D.isInvalidType()) 1832 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1833 D.setInvalidType(); 1834 1835 // Just pretend that we didn't see the previous declaration. 1836 PrevDecl = 0; 1837 } 1838 1839 // In C++, the previous declaration we find might be a tag type 1840 // (class or enum). In this case, the new declaration will hide the 1841 // tag type. Note that this does does not apply if we're declaring a 1842 // typedef (C++ [dcl.typedef]p4). 1843 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1844 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1845 PrevDecl = 0; 1846 1847 bool Redeclaration = false; 1848 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1849 if (TemplateParamLists.size()) { 1850 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1851 return DeclPtrTy(); 1852 } 1853 1854 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1855 } else if (R->isFunctionType()) { 1856 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1857 move(TemplateParamLists), 1858 IsFunctionDefinition, Redeclaration); 1859 } else { 1860 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1861 move(TemplateParamLists), 1862 Redeclaration); 1863 } 1864 1865 if (New == 0) 1866 return DeclPtrTy(); 1867 1868 // If this has an identifier and is not an invalid redeclaration or 1869 // function template specialization, add it to the scope stack. 1870 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1871 !(isa<FunctionDecl>(New) && 1872 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1873 PushOnScopeChains(New, S); 1874 1875 return DeclPtrTy::make(New); 1876} 1877 1878/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1879/// types into constant array types in certain situations which would otherwise 1880/// be errors (for GCC compatibility). 1881static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1882 ASTContext &Context, 1883 bool &SizeIsNegative) { 1884 // This method tries to turn a variable array into a constant 1885 // array even when the size isn't an ICE. This is necessary 1886 // for compatibility with code that depends on gcc's buggy 1887 // constant expression folding, like struct {char x[(int)(char*)2];} 1888 SizeIsNegative = false; 1889 1890 QualifierCollector Qs; 1891 const Type *Ty = Qs.strip(T); 1892 1893 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1894 QualType Pointee = PTy->getPointeeType(); 1895 QualType FixedType = 1896 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1897 if (FixedType.isNull()) return FixedType; 1898 FixedType = Context.getPointerType(FixedType); 1899 return Qs.apply(FixedType); 1900 } 1901 1902 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1903 if (!VLATy) 1904 return QualType(); 1905 // FIXME: We should probably handle this case 1906 if (VLATy->getElementType()->isVariablyModifiedType()) 1907 return QualType(); 1908 1909 Expr::EvalResult EvalResult; 1910 if (!VLATy->getSizeExpr() || 1911 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1912 !EvalResult.Val.isInt()) 1913 return QualType(); 1914 1915 llvm::APSInt &Res = EvalResult.Val.getInt(); 1916 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1917 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1918 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1919 // so as to transfer ownership to the ConstantArrayWithExpr. 1920 // Alternatively, we could "clone" it (how?). 1921 // Since we don't know how to do things above, we just use the 1922 // very same Expr*. 1923 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1924 Res, ArySizeExpr, 1925 ArrayType::Normal, 0, 1926 VLATy->getBracketsRange()); 1927 } 1928 1929 SizeIsNegative = true; 1930 return QualType(); 1931} 1932 1933/// \brief Register the given locally-scoped external C declaration so 1934/// that it can be found later for redeclarations 1935void 1936Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1937 Scope *S) { 1938 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1939 "Decl is not a locally-scoped decl!"); 1940 // Note that we have a locally-scoped external with this name. 1941 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1942 1943 if (!PrevDecl) 1944 return; 1945 1946 // If there was a previous declaration of this variable, it may be 1947 // in our identifier chain. Update the identifier chain with the new 1948 // declaration. 1949 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1950 // The previous declaration was found on the identifer resolver 1951 // chain, so remove it from its scope. 1952 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1953 S = S->getParent(); 1954 1955 if (S) 1956 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1957 } 1958} 1959 1960/// \brief Diagnose function specifiers on a declaration of an identifier that 1961/// does not identify a function. 1962void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1963 // FIXME: We should probably indicate the identifier in question to avoid 1964 // confusion for constructs like "inline int a(), b;" 1965 if (D.getDeclSpec().isInlineSpecified()) 1966 Diag(D.getDeclSpec().getInlineSpecLoc(), 1967 diag::err_inline_non_function); 1968 1969 if (D.getDeclSpec().isVirtualSpecified()) 1970 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1971 diag::err_virtual_non_function); 1972 1973 if (D.getDeclSpec().isExplicitSpecified()) 1974 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1975 diag::err_explicit_non_function); 1976} 1977 1978NamedDecl* 1979Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1980 QualType R, DeclaratorInfo *DInfo, 1981 NamedDecl* PrevDecl, bool &Redeclaration) { 1982 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1983 if (D.getCXXScopeSpec().isSet()) { 1984 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1985 << D.getCXXScopeSpec().getRange(); 1986 D.setInvalidType(); 1987 // Pretend we didn't see the scope specifier. 1988 DC = 0; 1989 } 1990 1991 if (getLangOptions().CPlusPlus) { 1992 // Check that there are no default arguments (C++ only). 1993 CheckExtraCXXDefaultArguments(D); 1994 } 1995 1996 DiagnoseFunctionSpecifiers(D); 1997 1998 if (D.getDeclSpec().isThreadSpecified()) 1999 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2000 2001 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 2002 if (!NewTD) return 0; 2003 2004 if (D.isInvalidType()) 2005 NewTD->setInvalidDecl(); 2006 2007 // Handle attributes prior to checking for duplicates in MergeVarDecl 2008 ProcessDeclAttributes(S, NewTD, D); 2009 // Merge the decl with the existing one if appropriate. If the decl is 2010 // in an outer scope, it isn't the same thing. 2011 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2012 Redeclaration = true; 2013 MergeTypeDefDecl(NewTD, PrevDecl); 2014 } 2015 2016 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2017 // then it shall have block scope. 2018 QualType T = NewTD->getUnderlyingType(); 2019 if (T->isVariablyModifiedType()) { 2020 CurFunctionNeedsScopeChecking = true; 2021 2022 if (S->getFnParent() == 0) { 2023 bool SizeIsNegative; 2024 QualType FixedTy = 2025 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2026 if (!FixedTy.isNull()) { 2027 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2028 NewTD->setUnderlyingType(FixedTy); 2029 } else { 2030 if (SizeIsNegative) 2031 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2032 else if (T->isVariableArrayType()) 2033 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2034 else 2035 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2036 NewTD->setInvalidDecl(); 2037 } 2038 } 2039 } 2040 2041 // If this is the C FILE type, notify the AST context. 2042 if (IdentifierInfo *II = NewTD->getIdentifier()) 2043 if (!NewTD->isInvalidDecl() && 2044 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2045 if (II->isStr("FILE")) 2046 Context.setFILEDecl(NewTD); 2047 else if (II->isStr("jmp_buf")) 2048 Context.setjmp_bufDecl(NewTD); 2049 else if (II->isStr("sigjmp_buf")) 2050 Context.setsigjmp_bufDecl(NewTD); 2051 } 2052 2053 return NewTD; 2054} 2055 2056/// \brief Determines whether the given declaration is an out-of-scope 2057/// previous declaration. 2058/// 2059/// This routine should be invoked when name lookup has found a 2060/// previous declaration (PrevDecl) that is not in the scope where a 2061/// new declaration by the same name is being introduced. If the new 2062/// declaration occurs in a local scope, previous declarations with 2063/// linkage may still be considered previous declarations (C99 2064/// 6.2.2p4-5, C++ [basic.link]p6). 2065/// 2066/// \param PrevDecl the previous declaration found by name 2067/// lookup 2068/// 2069/// \param DC the context in which the new declaration is being 2070/// declared. 2071/// 2072/// \returns true if PrevDecl is an out-of-scope previous declaration 2073/// for a new delcaration with the same name. 2074static bool 2075isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2076 ASTContext &Context) { 2077 if (!PrevDecl) 2078 return 0; 2079 2080 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2081 // case we need to check each of the overloaded functions. 2082 if (!PrevDecl->hasLinkage()) 2083 return false; 2084 2085 if (Context.getLangOptions().CPlusPlus) { 2086 // C++ [basic.link]p6: 2087 // If there is a visible declaration of an entity with linkage 2088 // having the same name and type, ignoring entities declared 2089 // outside the innermost enclosing namespace scope, the block 2090 // scope declaration declares that same entity and receives the 2091 // linkage of the previous declaration. 2092 DeclContext *OuterContext = DC->getLookupContext(); 2093 if (!OuterContext->isFunctionOrMethod()) 2094 // This rule only applies to block-scope declarations. 2095 return false; 2096 else { 2097 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2098 if (PrevOuterContext->isRecord()) 2099 // We found a member function: ignore it. 2100 return false; 2101 else { 2102 // Find the innermost enclosing namespace for the new and 2103 // previous declarations. 2104 while (!OuterContext->isFileContext()) 2105 OuterContext = OuterContext->getParent(); 2106 while (!PrevOuterContext->isFileContext()) 2107 PrevOuterContext = PrevOuterContext->getParent(); 2108 2109 // The previous declaration is in a different namespace, so it 2110 // isn't the same function. 2111 if (OuterContext->getPrimaryContext() != 2112 PrevOuterContext->getPrimaryContext()) 2113 return false; 2114 } 2115 } 2116 } 2117 2118 return true; 2119} 2120 2121NamedDecl* 2122Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2123 QualType R, DeclaratorInfo *DInfo, 2124 NamedDecl* PrevDecl, 2125 MultiTemplateParamsArg TemplateParamLists, 2126 bool &Redeclaration) { 2127 DeclarationName Name = GetNameForDeclarator(D); 2128 2129 // Check that there are no default arguments (C++ only). 2130 if (getLangOptions().CPlusPlus) 2131 CheckExtraCXXDefaultArguments(D); 2132 2133 VarDecl *NewVD; 2134 VarDecl::StorageClass SC; 2135 switch (D.getDeclSpec().getStorageClassSpec()) { 2136 default: assert(0 && "Unknown storage class!"); 2137 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2138 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2139 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2140 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2141 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2142 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2143 case DeclSpec::SCS_mutable: 2144 // mutable can only appear on non-static class members, so it's always 2145 // an error here 2146 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2147 D.setInvalidType(); 2148 SC = VarDecl::None; 2149 break; 2150 } 2151 2152 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2153 if (!II) { 2154 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2155 << Name.getAsString(); 2156 return 0; 2157 } 2158 2159 DiagnoseFunctionSpecifiers(D); 2160 2161 if (!DC->isRecord() && S->getFnParent() == 0) { 2162 // C99 6.9p2: The storage-class specifiers auto and register shall not 2163 // appear in the declaration specifiers in an external declaration. 2164 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2165 2166 // If this is a register variable with an asm label specified, then this 2167 // is a GNU extension. 2168 if (SC == VarDecl::Register && D.getAsmLabel()) 2169 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2170 else 2171 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2172 D.setInvalidType(); 2173 } 2174 } 2175 if (DC->isRecord() && !CurContext->isRecord()) { 2176 // This is an out-of-line definition of a static data member. 2177 if (SC == VarDecl::Static) { 2178 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2179 diag::err_static_out_of_line) 2180 << CodeModificationHint::CreateRemoval( 2181 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2182 } else if (SC == VarDecl::None) 2183 SC = VarDecl::Static; 2184 } 2185 if (SC == VarDecl::Static) { 2186 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2187 if (RD->isLocalClass()) 2188 Diag(D.getIdentifierLoc(), 2189 diag::err_static_data_member_not_allowed_in_local_class) 2190 << Name << RD->getDeclName(); 2191 } 2192 } 2193 2194 // Match up the template parameter lists with the scope specifier, then 2195 // determine whether we have a template or a template specialization. 2196 bool isExplicitSpecialization = false; 2197 if (TemplateParameterList *TemplateParams 2198 = MatchTemplateParametersToScopeSpecifier( 2199 D.getDeclSpec().getSourceRange().getBegin(), 2200 D.getCXXScopeSpec(), 2201 (TemplateParameterList**)TemplateParamLists.get(), 2202 TemplateParamLists.size(), 2203 isExplicitSpecialization)) { 2204 if (TemplateParams->size() > 0) { 2205 // There is no such thing as a variable template. 2206 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2207 << II 2208 << SourceRange(TemplateParams->getTemplateLoc(), 2209 TemplateParams->getRAngleLoc()); 2210 return 0; 2211 } else { 2212 // There is an extraneous 'template<>' for this variable. Complain 2213 // about it, but allow the declaration of the variable. 2214 Diag(TemplateParams->getTemplateLoc(), 2215 diag::err_template_variable_noparams) 2216 << II 2217 << SourceRange(TemplateParams->getTemplateLoc(), 2218 TemplateParams->getRAngleLoc()); 2219 2220 isExplicitSpecialization = true; 2221 } 2222 } 2223 2224 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2225 II, R, DInfo, SC); 2226 2227 if (D.isInvalidType()) 2228 NewVD->setInvalidDecl(); 2229 2230 if (D.getDeclSpec().isThreadSpecified()) { 2231 if (NewVD->hasLocalStorage()) 2232 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2233 else if (!Context.Target.isTLSSupported()) 2234 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2235 else 2236 NewVD->setThreadSpecified(true); 2237 } 2238 2239 // Set the lexical context. If the declarator has a C++ scope specifier, the 2240 // lexical context will be different from the semantic context. 2241 NewVD->setLexicalDeclContext(CurContext); 2242 2243 // Handle attributes prior to checking for duplicates in MergeVarDecl 2244 ProcessDeclAttributes(S, NewVD, D); 2245 2246 // Handle GNU asm-label extension (encoded as an attribute). 2247 if (Expr *E = (Expr*) D.getAsmLabel()) { 2248 // The parser guarantees this is a string. 2249 StringLiteral *SE = cast<StringLiteral>(E); 2250 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2251 SE->getByteLength()))); 2252 } 2253 2254 // If name lookup finds a previous declaration that is not in the 2255 // same scope as the new declaration, this may still be an 2256 // acceptable redeclaration. 2257 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2258 !(NewVD->hasLinkage() && 2259 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2260 PrevDecl = 0; 2261 2262 // Merge the decl with the existing one if appropriate. 2263 if (PrevDecl) { 2264 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2265 // The user tried to define a non-static data member 2266 // out-of-line (C++ [dcl.meaning]p1). 2267 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2268 << D.getCXXScopeSpec().getRange(); 2269 PrevDecl = 0; 2270 NewVD->setInvalidDecl(); 2271 } 2272 } else if (D.getCXXScopeSpec().isSet()) { 2273 // No previous declaration in the qualifying scope. 2274 NestedNameSpecifier *NNS = 2275 (NestedNameSpecifier *)D.getCXXScopeSpec().getScopeRep(); 2276 DiagnoseMissingMember(D.getIdentifierLoc(), Name, NNS, 2277 D.getCXXScopeSpec().getRange()); 2278 NewVD->setInvalidDecl(); 2279 } 2280 2281 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2282 2283 // This is an explicit specialization of a static data member. Check it. 2284 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2285 CheckMemberSpecialization(NewVD, PrevDecl)) 2286 NewVD->setInvalidDecl(); 2287 2288 // attributes declared post-definition are currently ignored 2289 if (PrevDecl) { 2290 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2291 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2292 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2293 Diag(Def->getLocation(), diag::note_previous_definition); 2294 } 2295 } 2296 2297 // If this is a locally-scoped extern C variable, update the map of 2298 // such variables. 2299 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2300 !NewVD->isInvalidDecl()) 2301 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2302 2303 return NewVD; 2304} 2305 2306/// \brief Perform semantic checking on a newly-created variable 2307/// declaration. 2308/// 2309/// This routine performs all of the type-checking required for a 2310/// variable declaration once it has been built. It is used both to 2311/// check variables after they have been parsed and their declarators 2312/// have been translated into a declaration, and to check variables 2313/// that have been instantiated from a template. 2314/// 2315/// Sets NewVD->isInvalidDecl() if an error was encountered. 2316void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2317 bool &Redeclaration) { 2318 // If the decl is already known invalid, don't check it. 2319 if (NewVD->isInvalidDecl()) 2320 return; 2321 2322 QualType T = NewVD->getType(); 2323 2324 if (T->isObjCInterfaceType()) { 2325 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2326 return NewVD->setInvalidDecl(); 2327 } 2328 2329 // The variable can not have an abstract class type. 2330 if (RequireNonAbstractType(NewVD->getLocation(), T, 2331 diag::err_abstract_type_in_decl, 2332 AbstractVariableType)) 2333 return NewVD->setInvalidDecl(); 2334 2335 // Emit an error if an address space was applied to decl with local storage. 2336 // This includes arrays of objects with address space qualifiers, but not 2337 // automatic variables that point to other address spaces. 2338 // ISO/IEC TR 18037 S5.1.2 2339 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2340 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2341 return NewVD->setInvalidDecl(); 2342 } 2343 2344 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2345 && !NewVD->hasAttr<BlocksAttr>()) 2346 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2347 2348 bool isVM = T->isVariablyModifiedType(); 2349 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2350 NewVD->hasAttr<BlocksAttr>()) 2351 CurFunctionNeedsScopeChecking = true; 2352 2353 if ((isVM && NewVD->hasLinkage()) || 2354 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2355 bool SizeIsNegative; 2356 QualType FixedTy = 2357 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2358 2359 if (FixedTy.isNull() && T->isVariableArrayType()) { 2360 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2361 // FIXME: This won't give the correct result for 2362 // int a[10][n]; 2363 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2364 2365 if (NewVD->isFileVarDecl()) 2366 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2367 << SizeRange; 2368 else if (NewVD->getStorageClass() == VarDecl::Static) 2369 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2370 << SizeRange; 2371 else 2372 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2373 << SizeRange; 2374 return NewVD->setInvalidDecl(); 2375 } 2376 2377 if (FixedTy.isNull()) { 2378 if (NewVD->isFileVarDecl()) 2379 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2380 else 2381 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2382 return NewVD->setInvalidDecl(); 2383 } 2384 2385 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2386 NewVD->setType(FixedTy); 2387 } 2388 2389 if (!PrevDecl && NewVD->isExternC()) { 2390 // Since we did not find anything by this name and we're declaring 2391 // an extern "C" variable, look for a non-visible extern "C" 2392 // declaration with the same name. 2393 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2394 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2395 if (Pos != LocallyScopedExternalDecls.end()) 2396 PrevDecl = Pos->second; 2397 } 2398 2399 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2400 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2401 << T; 2402 return NewVD->setInvalidDecl(); 2403 } 2404 2405 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2406 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2407 return NewVD->setInvalidDecl(); 2408 } 2409 2410 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2411 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2412 return NewVD->setInvalidDecl(); 2413 } 2414 2415 if (PrevDecl) { 2416 Redeclaration = true; 2417 MergeVarDecl(NewVD, PrevDecl); 2418 } 2419} 2420 2421static bool isUsingDecl(Decl *D) { 2422 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2423} 2424 2425/// \brief Data used with FindOverriddenMethod 2426struct FindOverriddenMethodData { 2427 Sema *S; 2428 CXXMethodDecl *Method; 2429}; 2430 2431/// \brief Member lookup function that determines whether a given C++ 2432/// method overrides a method in a base class, to be used with 2433/// CXXRecordDecl::lookupInBases(). 2434static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2435 CXXBasePath &Path, 2436 void *UserData) { 2437 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2438 2439 FindOverriddenMethodData *Data 2440 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2441 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2442 Path.Decls.first != Path.Decls.second; 2443 ++Path.Decls.first) { 2444 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2445 OverloadedFunctionDecl::function_iterator MatchedDecl; 2446 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2447 return true; 2448 } 2449 } 2450 2451 return false; 2452} 2453 2454NamedDecl* 2455Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2456 QualType R, DeclaratorInfo *DInfo, 2457 NamedDecl* PrevDecl, 2458 MultiTemplateParamsArg TemplateParamLists, 2459 bool IsFunctionDefinition, bool &Redeclaration) { 2460 assert(R.getTypePtr()->isFunctionType()); 2461 2462 DeclarationName Name = GetNameForDeclarator(D); 2463 FunctionDecl::StorageClass SC = FunctionDecl::None; 2464 switch (D.getDeclSpec().getStorageClassSpec()) { 2465 default: assert(0 && "Unknown storage class!"); 2466 case DeclSpec::SCS_auto: 2467 case DeclSpec::SCS_register: 2468 case DeclSpec::SCS_mutable: 2469 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2470 diag::err_typecheck_sclass_func); 2471 D.setInvalidType(); 2472 break; 2473 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2474 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2475 case DeclSpec::SCS_static: { 2476 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2477 // C99 6.7.1p5: 2478 // The declaration of an identifier for a function that has 2479 // block scope shall have no explicit storage-class specifier 2480 // other than extern 2481 // See also (C++ [dcl.stc]p4). 2482 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2483 diag::err_static_block_func); 2484 SC = FunctionDecl::None; 2485 } else 2486 SC = FunctionDecl::Static; 2487 break; 2488 } 2489 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2490 } 2491 2492 if (D.getDeclSpec().isThreadSpecified()) 2493 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2494 2495 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2496 bool isInline = D.getDeclSpec().isInlineSpecified(); 2497 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2498 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2499 2500 // Check that the return type is not an abstract class type. 2501 // For record types, this is done by the AbstractClassUsageDiagnoser once 2502 // the class has been completely parsed. 2503 if (!DC->isRecord() && 2504 RequireNonAbstractType(D.getIdentifierLoc(), 2505 R->getAs<FunctionType>()->getResultType(), 2506 diag::err_abstract_type_in_decl, 2507 AbstractReturnType)) 2508 D.setInvalidType(); 2509 2510 // Do not allow returning a objc interface by-value. 2511 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2512 Diag(D.getIdentifierLoc(), 2513 diag::err_object_cannot_be_passed_returned_by_value) << 0 2514 << R->getAs<FunctionType>()->getResultType(); 2515 D.setInvalidType(); 2516 } 2517 2518 bool isVirtualOkay = false; 2519 FunctionDecl *NewFD; 2520 2521 if (isFriend) { 2522 // DC is the namespace in which the function is being declared. 2523 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2524 "friend function being created in a non-namespace context"); 2525 2526 // C++ [class.friend]p5 2527 // A function can be defined in a friend declaration of a 2528 // class . . . . Such a function is implicitly inline. 2529 isInline |= IsFunctionDefinition; 2530 } 2531 2532 if (D.getKind() == Declarator::DK_Constructor) { 2533 // This is a C++ constructor declaration. 2534 assert(DC->isRecord() && 2535 "Constructors can only be declared in a member context"); 2536 2537 R = CheckConstructorDeclarator(D, R, SC); 2538 2539 // Create the new declaration 2540 NewFD = CXXConstructorDecl::Create(Context, 2541 cast<CXXRecordDecl>(DC), 2542 D.getIdentifierLoc(), Name, R, DInfo, 2543 isExplicit, isInline, 2544 /*isImplicitlyDeclared=*/false); 2545 } else if (D.getKind() == Declarator::DK_Destructor) { 2546 // This is a C++ destructor declaration. 2547 if (DC->isRecord()) { 2548 R = CheckDestructorDeclarator(D, SC); 2549 2550 NewFD = CXXDestructorDecl::Create(Context, 2551 cast<CXXRecordDecl>(DC), 2552 D.getIdentifierLoc(), Name, R, 2553 isInline, 2554 /*isImplicitlyDeclared=*/false); 2555 2556 isVirtualOkay = true; 2557 } else { 2558 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2559 2560 // Create a FunctionDecl to satisfy the function definition parsing 2561 // code path. 2562 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2563 Name, R, DInfo, SC, isInline, 2564 /*hasPrototype=*/true); 2565 D.setInvalidType(); 2566 } 2567 } else if (D.getKind() == Declarator::DK_Conversion) { 2568 if (!DC->isRecord()) { 2569 Diag(D.getIdentifierLoc(), 2570 diag::err_conv_function_not_member); 2571 return 0; 2572 } 2573 2574 CheckConversionDeclarator(D, R, SC); 2575 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2576 D.getIdentifierLoc(), Name, R, DInfo, 2577 isInline, isExplicit); 2578 2579 isVirtualOkay = true; 2580 } else if (DC->isRecord()) { 2581 // If the of the function is the same as the name of the record, then this 2582 // must be an invalid constructor that has a return type. 2583 // (The parser checks for a return type and makes the declarator a 2584 // constructor if it has no return type). 2585 // must have an invalid constructor that has a return type 2586 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2587 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2588 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2589 << SourceRange(D.getIdentifierLoc()); 2590 return 0; 2591 } 2592 2593 // This is a C++ method declaration. 2594 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2595 D.getIdentifierLoc(), Name, R, DInfo, 2596 (SC == FunctionDecl::Static), isInline); 2597 2598 isVirtualOkay = (SC != FunctionDecl::Static); 2599 } else { 2600 // Determine whether the function was written with a 2601 // prototype. This true when: 2602 // - we're in C++ (where every function has a prototype), 2603 // - there is a prototype in the declarator, or 2604 // - the type R of the function is some kind of typedef or other reference 2605 // to a type name (which eventually refers to a function type). 2606 bool HasPrototype = 2607 getLangOptions().CPlusPlus || 2608 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2609 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2610 2611 NewFD = FunctionDecl::Create(Context, DC, 2612 D.getIdentifierLoc(), 2613 Name, R, DInfo, SC, isInline, HasPrototype); 2614 } 2615 2616 if (D.isInvalidType()) 2617 NewFD->setInvalidDecl(); 2618 2619 // Set the lexical context. If the declarator has a C++ 2620 // scope specifier, or is the object of a friend declaration, the 2621 // lexical context will be different from the semantic context. 2622 NewFD->setLexicalDeclContext(CurContext); 2623 2624 if (isFriend) 2625 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2626 2627 // Match up the template parameter lists with the scope specifier, then 2628 // determine whether we have a template or a template specialization. 2629 FunctionTemplateDecl *FunctionTemplate = 0; 2630 bool isExplicitSpecialization = false; 2631 bool isFunctionTemplateSpecialization = false; 2632 if (TemplateParameterList *TemplateParams 2633 = MatchTemplateParametersToScopeSpecifier( 2634 D.getDeclSpec().getSourceRange().getBegin(), 2635 D.getCXXScopeSpec(), 2636 (TemplateParameterList**)TemplateParamLists.get(), 2637 TemplateParamLists.size(), 2638 isExplicitSpecialization)) { 2639 if (TemplateParams->size() > 0) { 2640 // This is a function template 2641 2642 // Check that we can declare a template here. 2643 if (CheckTemplateDeclScope(S, TemplateParams)) 2644 return 0; 2645 2646 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2647 NewFD->getLocation(), 2648 Name, TemplateParams, 2649 NewFD); 2650 FunctionTemplate->setLexicalDeclContext(CurContext); 2651 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2652 } else { 2653 // This is a function template specialization. 2654 isFunctionTemplateSpecialization = true; 2655 } 2656 2657 // FIXME: Free this memory properly. 2658 TemplateParamLists.release(); 2659 } 2660 2661 // C++ [dcl.fct.spec]p5: 2662 // The virtual specifier shall only be used in declarations of 2663 // nonstatic class member functions that appear within a 2664 // member-specification of a class declaration; see 10.3. 2665 // 2666 if (isVirtual && !NewFD->isInvalidDecl()) { 2667 if (!isVirtualOkay) { 2668 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2669 diag::err_virtual_non_function); 2670 } else if (!CurContext->isRecord()) { 2671 // 'virtual' was specified outside of the class. 2672 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2673 << CodeModificationHint::CreateRemoval( 2674 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2675 } else { 2676 // Okay: Add virtual to the method. 2677 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2678 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2679 CurClass->setAggregate(false); 2680 CurClass->setPOD(false); 2681 CurClass->setEmpty(false); 2682 CurClass->setPolymorphic(true); 2683 CurClass->setHasTrivialConstructor(false); 2684 CurClass->setHasTrivialCopyConstructor(false); 2685 CurClass->setHasTrivialCopyAssignment(false); 2686 } 2687 } 2688 2689 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2690 // Look for virtual methods in base classes that this method might override. 2691 CXXBasePaths Paths; 2692 FindOverriddenMethodData Data; 2693 Data.Method = NewMD; 2694 Data.S = this; 2695 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2696 Paths)) { 2697 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2698 E = Paths.found_decls_end(); I != E; ++I) { 2699 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2700 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2701 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2702 NewMD->addOverriddenMethod(OldMD); 2703 } 2704 } 2705 } 2706 } 2707 2708 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2709 !CurContext->isRecord()) { 2710 // C++ [class.static]p1: 2711 // A data or function member of a class may be declared static 2712 // in a class definition, in which case it is a static member of 2713 // the class. 2714 2715 // Complain about the 'static' specifier if it's on an out-of-line 2716 // member function definition. 2717 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2718 diag::err_static_out_of_line) 2719 << CodeModificationHint::CreateRemoval( 2720 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2721 } 2722 2723 // Handle GNU asm-label extension (encoded as an attribute). 2724 if (Expr *E = (Expr*) D.getAsmLabel()) { 2725 // The parser guarantees this is a string. 2726 StringLiteral *SE = cast<StringLiteral>(E); 2727 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2728 SE->getByteLength()))); 2729 } 2730 2731 // Copy the parameter declarations from the declarator D to the function 2732 // declaration NewFD, if they are available. First scavenge them into Params. 2733 llvm::SmallVector<ParmVarDecl*, 16> Params; 2734 if (D.getNumTypeObjects() > 0) { 2735 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2736 2737 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2738 // function that takes no arguments, not a function that takes a 2739 // single void argument. 2740 // We let through "const void" here because Sema::GetTypeForDeclarator 2741 // already checks for that case. 2742 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2743 FTI.ArgInfo[0].Param && 2744 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2745 // Empty arg list, don't push any params. 2746 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2747 2748 // In C++, the empty parameter-type-list must be spelled "void"; a 2749 // typedef of void is not permitted. 2750 if (getLangOptions().CPlusPlus && 2751 Param->getType().getUnqualifiedType() != Context.VoidTy) 2752 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2753 // FIXME: Leaks decl? 2754 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2755 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2756 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2757 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2758 Param->setDeclContext(NewFD); 2759 Params.push_back(Param); 2760 } 2761 } 2762 2763 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2764 // When we're declaring a function with a typedef, typeof, etc as in the 2765 // following example, we'll need to synthesize (unnamed) 2766 // parameters for use in the declaration. 2767 // 2768 // @code 2769 // typedef void fn(int); 2770 // fn f; 2771 // @endcode 2772 2773 // Synthesize a parameter for each argument type. 2774 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2775 AE = FT->arg_type_end(); AI != AE; ++AI) { 2776 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2777 SourceLocation(), 0, 2778 *AI, /*DInfo=*/0, 2779 VarDecl::None, 0); 2780 Param->setImplicit(); 2781 Params.push_back(Param); 2782 } 2783 } else { 2784 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2785 "Should not need args for typedef of non-prototype fn"); 2786 } 2787 // Finally, we know we have the right number of parameters, install them. 2788 NewFD->setParams(Context, Params.data(), Params.size()); 2789 2790 // If name lookup finds a previous declaration that is not in the 2791 // same scope as the new declaration, this may still be an 2792 // acceptable redeclaration. 2793 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2794 !(NewFD->hasLinkage() && 2795 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2796 PrevDecl = 0; 2797 2798 // If the declarator is a template-id, translate the parser's template 2799 // argument list into our AST format. 2800 bool HasExplicitTemplateArgs = false; 2801 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2802 SourceLocation LAngleLoc, RAngleLoc; 2803 if (D.getKind() == Declarator::DK_TemplateId) { 2804 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2805 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2806 TemplateId->getTemplateArgs(), 2807 TemplateId->getTemplateArgIsType(), 2808 TemplateId->NumArgs); 2809 translateTemplateArguments(TemplateArgsPtr, 2810 TemplateId->getTemplateArgLocations(), 2811 TemplateArgs); 2812 TemplateArgsPtr.release(); 2813 2814 HasExplicitTemplateArgs = true; 2815 LAngleLoc = TemplateId->LAngleLoc; 2816 RAngleLoc = TemplateId->RAngleLoc; 2817 2818 if (FunctionTemplate) { 2819 // FIXME: Diagnose function template with explicit template 2820 // arguments. 2821 HasExplicitTemplateArgs = false; 2822 } else if (!isFunctionTemplateSpecialization && 2823 !D.getDeclSpec().isFriendSpecified()) { 2824 // We have encountered something that the user meant to be a 2825 // specialization (because it has explicitly-specified template 2826 // arguments) but that was not introduced with a "template<>" (or had 2827 // too few of them). 2828 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2829 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2830 << CodeModificationHint::CreateInsertion( 2831 D.getDeclSpec().getSourceRange().getBegin(), 2832 "template<> "); 2833 isFunctionTemplateSpecialization = true; 2834 } 2835 } 2836 2837 if (isFunctionTemplateSpecialization) { 2838 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2839 LAngleLoc, TemplateArgs.data(), 2840 TemplateArgs.size(), RAngleLoc, 2841 PrevDecl)) 2842 NewFD->setInvalidDecl(); 2843 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2844 CheckMemberSpecialization(NewFD, PrevDecl)) 2845 NewFD->setInvalidDecl(); 2846 2847 // Perform semantic checking on the function declaration. 2848 bool OverloadableAttrRequired = false; // FIXME: HACK! 2849 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2850 /*FIXME:*/OverloadableAttrRequired); 2851 2852 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2853 // An out-of-line member function declaration must also be a 2854 // definition (C++ [dcl.meaning]p1). 2855 // FIXME: Find a better way to recognize out-of-line specializations! 2856 if (!IsFunctionDefinition && !isFriend && 2857 !(TemplateParamLists.size() && !FunctionTemplate)) { 2858 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2859 << D.getCXXScopeSpec().getRange(); 2860 NewFD->setInvalidDecl(); 2861 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2862 // The user tried to provide an out-of-line definition for a 2863 // function that is a member of a class or namespace, but there 2864 // was no such member function declared (C++ [class.mfct]p2, 2865 // C++ [namespace.memdef]p2). For example: 2866 // 2867 // class X { 2868 // void f() const; 2869 // }; 2870 // 2871 // void X::f() { } // ill-formed 2872 // 2873 // Complain about this problem, and attempt to suggest close 2874 // matches (e.g., those that differ only in cv-qualifiers and 2875 // whether the parameter types are references). 2876 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2877 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2878 NewFD->setInvalidDecl(); 2879 2880 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2881 true); 2882 assert(!Prev.isAmbiguous() && 2883 "Cannot have an ambiguity in previous-declaration lookup"); 2884 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2885 Func != FuncEnd; ++Func) { 2886 if (isa<FunctionDecl>(*Func) && 2887 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2888 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2889 } 2890 2891 PrevDecl = 0; 2892 } 2893 } 2894 2895 // Handle attributes. We need to have merged decls when handling attributes 2896 // (for example to check for conflicts, etc). 2897 // FIXME: This needs to happen before we merge declarations. Then, 2898 // let attribute merging cope with attribute conflicts. 2899 ProcessDeclAttributes(S, NewFD, D); 2900 2901 // attributes declared post-definition are currently ignored 2902 if (Redeclaration && PrevDecl) { 2903 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2904 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2905 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2906 Diag(Def->getLocation(), diag::note_previous_definition); 2907 } 2908 } 2909 2910 AddKnownFunctionAttributes(NewFD); 2911 2912 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2913 // If a function name is overloadable in C, then every function 2914 // with that name must be marked "overloadable". 2915 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2916 << Redeclaration << NewFD; 2917 if (PrevDecl) 2918 Diag(PrevDecl->getLocation(), 2919 diag::note_attribute_overloadable_prev_overload); 2920 NewFD->addAttr(::new (Context) OverloadableAttr()); 2921 } 2922 2923 // If this is a locally-scoped extern C function, update the 2924 // map of such names. 2925 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2926 && !NewFD->isInvalidDecl()) 2927 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2928 2929 // Set this FunctionDecl's range up to the right paren. 2930 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2931 2932 if (FunctionTemplate && NewFD->isInvalidDecl()) 2933 FunctionTemplate->setInvalidDecl(); 2934 2935 if (FunctionTemplate) 2936 return FunctionTemplate; 2937 2938 return NewFD; 2939} 2940 2941/// \brief Perform semantic checking of a new function declaration. 2942/// 2943/// Performs semantic analysis of the new function declaration 2944/// NewFD. This routine performs all semantic checking that does not 2945/// require the actual declarator involved in the declaration, and is 2946/// used both for the declaration of functions as they are parsed 2947/// (called via ActOnDeclarator) and for the declaration of functions 2948/// that have been instantiated via C++ template instantiation (called 2949/// via InstantiateDecl). 2950/// 2951/// This sets NewFD->isInvalidDecl() to true if there was an error. 2952void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2953 bool &Redeclaration, 2954 bool &OverloadableAttrRequired) { 2955 // If NewFD is already known erroneous, don't do any of this checking. 2956 if (NewFD->isInvalidDecl()) 2957 return; 2958 2959 if (NewFD->getResultType()->isVariablyModifiedType()) { 2960 // Functions returning a variably modified type violate C99 6.7.5.2p2 2961 // because all functions have linkage. 2962 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2963 return NewFD->setInvalidDecl(); 2964 } 2965 2966 if (NewFD->isMain()) 2967 CheckMain(NewFD); 2968 2969 // Check for a previous declaration of this name. 2970 if (!PrevDecl && NewFD->isExternC()) { 2971 // Since we did not find anything by this name and we're declaring 2972 // an extern "C" function, look for a non-visible extern "C" 2973 // declaration with the same name. 2974 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2975 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2976 if (Pos != LocallyScopedExternalDecls.end()) 2977 PrevDecl = Pos->second; 2978 } 2979 2980 // Merge or overload the declaration with an existing declaration of 2981 // the same name, if appropriate. 2982 if (PrevDecl) { 2983 // Determine whether NewFD is an overload of PrevDecl or 2984 // a declaration that requires merging. If it's an overload, 2985 // there's no more work to do here; we'll just add the new 2986 // function to the scope. 2987 OverloadedFunctionDecl::function_iterator MatchedDecl; 2988 2989 if (!getLangOptions().CPlusPlus && 2990 AllowOverloadingOfFunction(PrevDecl, Context)) { 2991 OverloadableAttrRequired = true; 2992 2993 // Functions marked "overloadable" must have a prototype (that 2994 // we can't get through declaration merging). 2995 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2996 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2997 << NewFD; 2998 Redeclaration = true; 2999 3000 // Turn this into a variadic function with no parameters. 3001 QualType R = Context.getFunctionType( 3002 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3003 0, 0, true, 0); 3004 NewFD->setType(R); 3005 return NewFD->setInvalidDecl(); 3006 } 3007 } 3008 3009 if (PrevDecl && 3010 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3011 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3012 Redeclaration = true; 3013 Decl *OldDecl = PrevDecl; 3014 3015 // If PrevDecl was an overloaded function, extract the 3016 // FunctionDecl that matched. 3017 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3018 OldDecl = *MatchedDecl; 3019 3020 // NewFD and OldDecl represent declarations that need to be 3021 // merged. 3022 if (MergeFunctionDecl(NewFD, OldDecl)) 3023 return NewFD->setInvalidDecl(); 3024 3025 if (FunctionTemplateDecl *OldTemplateDecl 3026 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 3027 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3028 else { 3029 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3030 NewFD->setAccess(OldDecl->getAccess()); 3031 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3032 } 3033 } 3034 } 3035 3036 // Semantic checking for this function declaration (in isolation). 3037 if (getLangOptions().CPlusPlus) { 3038 // C++-specific checks. 3039 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3040 CheckConstructor(Constructor); 3041 } else if (isa<CXXDestructorDecl>(NewFD)) { 3042 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3043 QualType ClassType = Context.getTypeDeclType(Record); 3044 if (!ClassType->isDependentType()) { 3045 DeclarationName Name 3046 = Context.DeclarationNames.getCXXDestructorName( 3047 Context.getCanonicalType(ClassType)); 3048 if (NewFD->getDeclName() != Name) { 3049 Diag(NewFD->getLocation(), diag::err_destructor_name); 3050 return NewFD->setInvalidDecl(); 3051 } 3052 } 3053 Record->setUserDeclaredDestructor(true); 3054 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3055 // user-defined destructor. 3056 Record->setPOD(false); 3057 3058 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3059 // declared destructor. 3060 // FIXME: C++0x: don't do this for "= default" destructors 3061 Record->setHasTrivialDestructor(false); 3062 } else if (CXXConversionDecl *Conversion 3063 = dyn_cast<CXXConversionDecl>(NewFD)) 3064 ActOnConversionDeclarator(Conversion); 3065 3066 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3067 if (NewFD->isOverloadedOperator() && 3068 CheckOverloadedOperatorDeclaration(NewFD)) 3069 return NewFD->setInvalidDecl(); 3070 3071 // In C++, check default arguments now that we have merged decls. Unless 3072 // the lexical context is the class, because in this case this is done 3073 // during delayed parsing anyway. 3074 if (!CurContext->isRecord()) 3075 CheckCXXDefaultArguments(NewFD); 3076 } 3077} 3078 3079void Sema::CheckMain(FunctionDecl* FD) { 3080 // C++ [basic.start.main]p3: A program that declares main to be inline 3081 // or static is ill-formed. 3082 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3083 // shall not appear in a declaration of main. 3084 // static main is not an error under C99, but we should warn about it. 3085 bool isInline = FD->isInline(); 3086 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3087 if (isInline || isStatic) { 3088 unsigned diagID = diag::warn_unusual_main_decl; 3089 if (isInline || getLangOptions().CPlusPlus) 3090 diagID = diag::err_unusual_main_decl; 3091 3092 int which = isStatic + (isInline << 1) - 1; 3093 Diag(FD->getLocation(), diagID) << which; 3094 } 3095 3096 QualType T = FD->getType(); 3097 assert(T->isFunctionType() && "function decl is not of function type"); 3098 const FunctionType* FT = T->getAs<FunctionType>(); 3099 3100 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3101 // TODO: add a replacement fixit to turn the return type into 'int'. 3102 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3103 FD->setInvalidDecl(true); 3104 } 3105 3106 // Treat protoless main() as nullary. 3107 if (isa<FunctionNoProtoType>(FT)) return; 3108 3109 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3110 unsigned nparams = FTP->getNumArgs(); 3111 assert(FD->getNumParams() == nparams); 3112 3113 if (nparams > 3) { 3114 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3115 FD->setInvalidDecl(true); 3116 nparams = 3; 3117 } 3118 3119 // FIXME: a lot of the following diagnostics would be improved 3120 // if we had some location information about types. 3121 3122 QualType CharPP = 3123 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3124 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3125 3126 for (unsigned i = 0; i < nparams; ++i) { 3127 QualType AT = FTP->getArgType(i); 3128 3129 bool mismatch = true; 3130 3131 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3132 mismatch = false; 3133 else if (Expected[i] == CharPP) { 3134 // As an extension, the following forms are okay: 3135 // char const ** 3136 // char const * const * 3137 // char * const * 3138 3139 QualifierCollector qs; 3140 const PointerType* PT; 3141 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3142 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3143 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3144 qs.removeConst(); 3145 mismatch = !qs.empty(); 3146 } 3147 } 3148 3149 if (mismatch) { 3150 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3151 // TODO: suggest replacing given type with expected type 3152 FD->setInvalidDecl(true); 3153 } 3154 } 3155 3156 if (nparams == 1 && !FD->isInvalidDecl()) { 3157 Diag(FD->getLocation(), diag::warn_main_one_arg); 3158 } 3159} 3160 3161bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3162 // FIXME: Need strict checking. In C89, we need to check for 3163 // any assignment, increment, decrement, function-calls, or 3164 // commas outside of a sizeof. In C99, it's the same list, 3165 // except that the aforementioned are allowed in unevaluated 3166 // expressions. Everything else falls under the 3167 // "may accept other forms of constant expressions" exception. 3168 // (We never end up here for C++, so the constant expression 3169 // rules there don't matter.) 3170 if (Init->isConstantInitializer(Context)) 3171 return false; 3172 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3173 << Init->getSourceRange(); 3174 return true; 3175} 3176 3177void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3178 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3179} 3180 3181/// AddInitializerToDecl - Adds the initializer Init to the 3182/// declaration dcl. If DirectInit is true, this is C++ direct 3183/// initialization rather than copy initialization. 3184void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3185 Decl *RealDecl = dcl.getAs<Decl>(); 3186 // If there is no declaration, there was an error parsing it. Just ignore 3187 // the initializer. 3188 if (RealDecl == 0) 3189 return; 3190 3191 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3192 // With declarators parsed the way they are, the parser cannot 3193 // distinguish between a normal initializer and a pure-specifier. 3194 // Thus this grotesque test. 3195 IntegerLiteral *IL; 3196 Expr *Init = static_cast<Expr *>(init.get()); 3197 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3198 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3199 if (Method->isVirtualAsWritten()) { 3200 Method->setPure(); 3201 3202 // A class is abstract if at least one function is pure virtual. 3203 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3204 } else if (!Method->isInvalidDecl()) { 3205 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3206 << Method->getDeclName() << Init->getSourceRange(); 3207 Method->setInvalidDecl(); 3208 } 3209 } else { 3210 Diag(Method->getLocation(), diag::err_member_function_initialization) 3211 << Method->getDeclName() << Init->getSourceRange(); 3212 Method->setInvalidDecl(); 3213 } 3214 return; 3215 } 3216 3217 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3218 if (!VDecl) { 3219 if (getLangOptions().CPlusPlus && 3220 RealDecl->getLexicalDeclContext()->isRecord() && 3221 isa<NamedDecl>(RealDecl)) 3222 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3223 << cast<NamedDecl>(RealDecl)->getDeclName(); 3224 else 3225 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3226 RealDecl->setInvalidDecl(); 3227 return; 3228 } 3229 3230 if (!VDecl->getType()->isArrayType() && 3231 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3232 diag::err_typecheck_decl_incomplete_type)) { 3233 RealDecl->setInvalidDecl(); 3234 return; 3235 } 3236 3237 const VarDecl *Def = 0; 3238 if (VDecl->getDefinition(Def)) { 3239 Diag(VDecl->getLocation(), diag::err_redefinition) 3240 << VDecl->getDeclName(); 3241 Diag(Def->getLocation(), diag::note_previous_definition); 3242 VDecl->setInvalidDecl(); 3243 return; 3244 } 3245 3246 // Take ownership of the expression, now that we're sure we have somewhere 3247 // to put it. 3248 Expr *Init = init.takeAs<Expr>(); 3249 assert(Init && "missing initializer"); 3250 3251 // Get the decls type and save a reference for later, since 3252 // CheckInitializerTypes may change it. 3253 QualType DclT = VDecl->getType(), SavT = DclT; 3254 if (VDecl->isBlockVarDecl()) { 3255 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3256 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3257 VDecl->setInvalidDecl(); 3258 } else if (!VDecl->isInvalidDecl()) { 3259 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3260 VDecl->getDeclName(), DirectInit)) 3261 VDecl->setInvalidDecl(); 3262 3263 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3264 // Don't check invalid declarations to avoid emitting useless diagnostics. 3265 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3266 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3267 CheckForConstantInitializer(Init, DclT); 3268 } 3269 } 3270 } else if (VDecl->isStaticDataMember() && 3271 VDecl->getLexicalDeclContext()->isRecord()) { 3272 // This is an in-class initialization for a static data member, e.g., 3273 // 3274 // struct S { 3275 // static const int value = 17; 3276 // }; 3277 3278 // Attach the initializer 3279 VDecl->setInit(Context, Init); 3280 3281 // C++ [class.mem]p4: 3282 // A member-declarator can contain a constant-initializer only 3283 // if it declares a static member (9.4) of const integral or 3284 // const enumeration type, see 9.4.2. 3285 QualType T = VDecl->getType(); 3286 if (!T->isDependentType() && 3287 (!Context.getCanonicalType(T).isConstQualified() || 3288 !T->isIntegralType())) { 3289 Diag(VDecl->getLocation(), diag::err_member_initialization) 3290 << VDecl->getDeclName() << Init->getSourceRange(); 3291 VDecl->setInvalidDecl(); 3292 } else { 3293 // C++ [class.static.data]p4: 3294 // If a static data member is of const integral or const 3295 // enumeration type, its declaration in the class definition 3296 // can specify a constant-initializer which shall be an 3297 // integral constant expression (5.19). 3298 if (!Init->isTypeDependent() && 3299 !Init->getType()->isIntegralType()) { 3300 // We have a non-dependent, non-integral or enumeration type. 3301 Diag(Init->getSourceRange().getBegin(), 3302 diag::err_in_class_initializer_non_integral_type) 3303 << Init->getType() << Init->getSourceRange(); 3304 VDecl->setInvalidDecl(); 3305 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3306 // Check whether the expression is a constant expression. 3307 llvm::APSInt Value; 3308 SourceLocation Loc; 3309 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3310 Diag(Loc, diag::err_in_class_initializer_non_constant) 3311 << Init->getSourceRange(); 3312 VDecl->setInvalidDecl(); 3313 } else if (!VDecl->getType()->isDependentType()) 3314 ImpCastExprToType(Init, VDecl->getType()); 3315 } 3316 } 3317 } else if (VDecl->isFileVarDecl()) { 3318 if (VDecl->getStorageClass() == VarDecl::Extern) 3319 Diag(VDecl->getLocation(), diag::warn_extern_init); 3320 if (!VDecl->isInvalidDecl()) 3321 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3322 VDecl->getDeclName(), DirectInit)) 3323 VDecl->setInvalidDecl(); 3324 3325 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3326 // Don't check invalid declarations to avoid emitting useless diagnostics. 3327 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3328 // C99 6.7.8p4. All file scoped initializers need to be constant. 3329 CheckForConstantInitializer(Init, DclT); 3330 } 3331 } 3332 // If the type changed, it means we had an incomplete type that was 3333 // completed by the initializer. For example: 3334 // int ary[] = { 1, 3, 5 }; 3335 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3336 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3337 VDecl->setType(DclT); 3338 Init->setType(DclT); 3339 } 3340 3341 Init = MaybeCreateCXXExprWithTemporaries(Init, 3342 /*ShouldDestroyTemporaries=*/true); 3343 // Attach the initializer to the decl. 3344 VDecl->setInit(Context, Init); 3345 3346 // If the previous declaration of VDecl was a tentative definition, 3347 // remove it from the set of tentative definitions. 3348 if (VDecl->getPreviousDeclaration() && 3349 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3350 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3351 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3352 } 3353 3354 return; 3355} 3356 3357void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3358 bool TypeContainsUndeducedAuto) { 3359 Decl *RealDecl = dcl.getAs<Decl>(); 3360 3361 // If there is no declaration, there was an error parsing it. Just ignore it. 3362 if (RealDecl == 0) 3363 return; 3364 3365 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3366 QualType Type = Var->getType(); 3367 3368 // Record tentative definitions. 3369 if (Var->isTentativeDefinition(Context)) { 3370 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3371 InsertPair = 3372 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3373 3374 // Keep the latest definition in the map. If we see 'int i; int i;' we 3375 // want the second one in the map. 3376 InsertPair.first->second = Var; 3377 3378 // However, for the list, we don't care about the order, just make sure 3379 // that there are no dupes for a given declaration name. 3380 if (InsertPair.second) 3381 TentativeDefinitionList.push_back(Var->getDeclName()); 3382 } 3383 3384 // C++ [dcl.init.ref]p3: 3385 // The initializer can be omitted for a reference only in a 3386 // parameter declaration (8.3.5), in the declaration of a 3387 // function return type, in the declaration of a class member 3388 // within its class declaration (9.2), and where the extern 3389 // specifier is explicitly used. 3390 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3391 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3392 << Var->getDeclName() 3393 << SourceRange(Var->getLocation(), Var->getLocation()); 3394 Var->setInvalidDecl(); 3395 return; 3396 } 3397 3398 // C++0x [dcl.spec.auto]p3 3399 if (TypeContainsUndeducedAuto) { 3400 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3401 << Var->getDeclName() << Type; 3402 Var->setInvalidDecl(); 3403 return; 3404 } 3405 3406 // C++ [temp.expl.spec]p15: 3407 // An explicit specialization of a static data member of a template is a 3408 // definition if the declaration includes an initializer; otherwise, it 3409 // is a declaration. 3410 if (Var->isStaticDataMember() && 3411 Var->getInstantiatedFromStaticDataMember() && 3412 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3413 return; 3414 3415 // C++ [dcl.init]p9: 3416 // If no initializer is specified for an object, and the object 3417 // is of (possibly cv-qualified) non-POD class type (or array 3418 // thereof), the object shall be default-initialized; if the 3419 // object is of const-qualified type, the underlying class type 3420 // shall have a user-declared default constructor. 3421 // 3422 // FIXME: Diagnose the "user-declared default constructor" bit. 3423 if (getLangOptions().CPlusPlus) { 3424 QualType InitType = Type; 3425 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3426 InitType = Array->getElementType(); 3427 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3428 InitType->isRecordType() && !InitType->isDependentType()) { 3429 if (!RequireCompleteType(Var->getLocation(), InitType, 3430 diag::err_invalid_incomplete_type_use)) { 3431 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3432 3433 CXXConstructorDecl *Constructor 3434 = PerformInitializationByConstructor(InitType, 3435 MultiExprArg(*this, 0, 0), 3436 Var->getLocation(), 3437 SourceRange(Var->getLocation(), 3438 Var->getLocation()), 3439 Var->getDeclName(), 3440 IK_Default, 3441 ConstructorArgs); 3442 3443 // FIXME: Location info for the variable initialization? 3444 if (!Constructor) 3445 Var->setInvalidDecl(); 3446 else { 3447 // FIXME: Cope with initialization of arrays 3448 if (!Constructor->isTrivial() && 3449 InitializeVarWithConstructor(Var, Constructor, InitType, 3450 move_arg(ConstructorArgs))) 3451 Var->setInvalidDecl(); 3452 3453 FinalizeVarWithDestructor(Var, InitType); 3454 } 3455 } 3456 } 3457 } 3458 3459#if 0 3460 // FIXME: Temporarily disabled because we are not properly parsing 3461 // linkage specifications on declarations, e.g., 3462 // 3463 // extern "C" const CGPoint CGPointerZero; 3464 // 3465 // C++ [dcl.init]p9: 3466 // 3467 // If no initializer is specified for an object, and the 3468 // object is of (possibly cv-qualified) non-POD class type (or 3469 // array thereof), the object shall be default-initialized; if 3470 // the object is of const-qualified type, the underlying class 3471 // type shall have a user-declared default 3472 // constructor. Otherwise, if no initializer is specified for 3473 // an object, the object and its subobjects, if any, have an 3474 // indeterminate initial value; if the object or any of its 3475 // subobjects are of const-qualified type, the program is 3476 // ill-formed. 3477 // 3478 // This isn't technically an error in C, so we don't diagnose it. 3479 // 3480 // FIXME: Actually perform the POD/user-defined default 3481 // constructor check. 3482 if (getLangOptions().CPlusPlus && 3483 Context.getCanonicalType(Type).isConstQualified() && 3484 !Var->hasExternalStorage()) 3485 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3486 << Var->getName() 3487 << SourceRange(Var->getLocation(), Var->getLocation()); 3488#endif 3489 } 3490} 3491 3492Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3493 DeclPtrTy *Group, 3494 unsigned NumDecls) { 3495 llvm::SmallVector<Decl*, 8> Decls; 3496 3497 if (DS.isTypeSpecOwned()) 3498 Decls.push_back((Decl*)DS.getTypeRep()); 3499 3500 for (unsigned i = 0; i != NumDecls; ++i) 3501 if (Decl *D = Group[i].getAs<Decl>()) 3502 Decls.push_back(D); 3503 3504 // Perform semantic analysis that depends on having fully processed both 3505 // the declarator and initializer. 3506 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3507 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3508 if (!IDecl) 3509 continue; 3510 QualType T = IDecl->getType(); 3511 3512 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3513 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3514 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3515 if (!IDecl->isInvalidDecl() && 3516 RequireCompleteType(IDecl->getLocation(), T, 3517 diag::err_typecheck_decl_incomplete_type)) 3518 IDecl->setInvalidDecl(); 3519 } 3520 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3521 // object that has file scope without an initializer, and without a 3522 // storage-class specifier or with the storage-class specifier "static", 3523 // constitutes a tentative definition. Note: A tentative definition with 3524 // external linkage is valid (C99 6.2.2p5). 3525 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3526 if (const IncompleteArrayType *ArrayT 3527 = Context.getAsIncompleteArrayType(T)) { 3528 if (RequireCompleteType(IDecl->getLocation(), 3529 ArrayT->getElementType(), 3530 diag::err_illegal_decl_array_incomplete_type)) 3531 IDecl->setInvalidDecl(); 3532 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3533 // C99 6.9.2p3: If the declaration of an identifier for an object is 3534 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3535 // declared type shall not be an incomplete type. 3536 // NOTE: code such as the following 3537 // static struct s; 3538 // struct s { int a; }; 3539 // is accepted by gcc. Hence here we issue a warning instead of 3540 // an error and we do not invalidate the static declaration. 3541 // NOTE: to avoid multiple warnings, only check the first declaration. 3542 if (IDecl->getPreviousDeclaration() == 0) 3543 RequireCompleteType(IDecl->getLocation(), T, 3544 diag::ext_typecheck_decl_incomplete_type); 3545 } 3546 } 3547 } 3548 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3549 Decls.data(), Decls.size())); 3550} 3551 3552 3553/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3554/// to introduce parameters into function prototype scope. 3555Sema::DeclPtrTy 3556Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3557 const DeclSpec &DS = D.getDeclSpec(); 3558 3559 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3560 VarDecl::StorageClass StorageClass = VarDecl::None; 3561 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3562 StorageClass = VarDecl::Register; 3563 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3564 Diag(DS.getStorageClassSpecLoc(), 3565 diag::err_invalid_storage_class_in_func_decl); 3566 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3567 } 3568 3569 if (D.getDeclSpec().isThreadSpecified()) 3570 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3571 3572 DiagnoseFunctionSpecifiers(D); 3573 3574 // Check that there are no default arguments inside the type of this 3575 // parameter (C++ only). 3576 if (getLangOptions().CPlusPlus) 3577 CheckExtraCXXDefaultArguments(D); 3578 3579 DeclaratorInfo *DInfo = 0; 3580 TagDecl *OwnedDecl = 0; 3581 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3582 &OwnedDecl); 3583 3584 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3585 // C++ [dcl.fct]p6: 3586 // Types shall not be defined in return or parameter types. 3587 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3588 << Context.getTypeDeclType(OwnedDecl); 3589 } 3590 3591 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3592 // Can this happen for params? We already checked that they don't conflict 3593 // among each other. Here they can only shadow globals, which is ok. 3594 IdentifierInfo *II = D.getIdentifier(); 3595 if (II) { 3596 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3597 if (PrevDecl->isTemplateParameter()) { 3598 // Maybe we will complain about the shadowed template parameter. 3599 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3600 // Just pretend that we didn't see the previous declaration. 3601 PrevDecl = 0; 3602 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3603 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3604 3605 // Recover by removing the name 3606 II = 0; 3607 D.SetIdentifier(0, D.getIdentifierLoc()); 3608 } 3609 } 3610 } 3611 3612 // Parameters can not be abstract class types. 3613 // For record types, this is done by the AbstractClassUsageDiagnoser once 3614 // the class has been completely parsed. 3615 if (!CurContext->isRecord() && 3616 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3617 diag::err_abstract_type_in_decl, 3618 AbstractParamType)) 3619 D.setInvalidType(true); 3620 3621 QualType T = adjustParameterType(parmDeclType); 3622 3623 ParmVarDecl *New; 3624 if (T == parmDeclType) // parameter type did not need adjustment 3625 New = ParmVarDecl::Create(Context, CurContext, 3626 D.getIdentifierLoc(), II, 3627 parmDeclType, DInfo, StorageClass, 3628 0); 3629 else // keep track of both the adjusted and unadjusted types 3630 New = OriginalParmVarDecl::Create(Context, CurContext, 3631 D.getIdentifierLoc(), II, T, DInfo, 3632 parmDeclType, StorageClass, 0); 3633 3634 if (D.isInvalidType()) 3635 New->setInvalidDecl(); 3636 3637 // Parameter declarators cannot be interface types. All ObjC objects are 3638 // passed by reference. 3639 if (T->isObjCInterfaceType()) { 3640 Diag(D.getIdentifierLoc(), 3641 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3642 New->setInvalidDecl(); 3643 } 3644 3645 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3646 if (D.getCXXScopeSpec().isSet()) { 3647 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3648 << D.getCXXScopeSpec().getRange(); 3649 New->setInvalidDecl(); 3650 } 3651 3652 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3653 // duration shall not be qualified by an address-space qualifier." 3654 // Since all parameters have automatic store duration, they can not have 3655 // an address space. 3656 if (T.getAddressSpace() != 0) { 3657 Diag(D.getIdentifierLoc(), 3658 diag::err_arg_with_address_space); 3659 New->setInvalidDecl(); 3660 } 3661 3662 3663 // Add the parameter declaration into this scope. 3664 S->AddDecl(DeclPtrTy::make(New)); 3665 if (II) 3666 IdResolver.AddDecl(New); 3667 3668 ProcessDeclAttributes(S, New, D); 3669 3670 if (New->hasAttr<BlocksAttr>()) { 3671 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3672 } 3673 return DeclPtrTy::make(New); 3674} 3675 3676void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3677 SourceLocation LocAfterDecls) { 3678 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3679 "Not a function declarator!"); 3680 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3681 3682 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3683 // for a K&R function. 3684 if (!FTI.hasPrototype) { 3685 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3686 --i; 3687 if (FTI.ArgInfo[i].Param == 0) { 3688 std::string Code = " int "; 3689 Code += FTI.ArgInfo[i].Ident->getName(); 3690 Code += ";\n"; 3691 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3692 << FTI.ArgInfo[i].Ident 3693 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3694 3695 // Implicitly declare the argument as type 'int' for lack of a better 3696 // type. 3697 DeclSpec DS; 3698 const char* PrevSpec; // unused 3699 unsigned DiagID; // unused 3700 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3701 PrevSpec, DiagID); 3702 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3703 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3704 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3705 } 3706 } 3707 } 3708} 3709 3710Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3711 Declarator &D) { 3712 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3713 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3714 "Not a function declarator!"); 3715 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3716 3717 if (FTI.hasPrototype) { 3718 // FIXME: Diagnose arguments without names in C. 3719 } 3720 3721 Scope *ParentScope = FnBodyScope->getParent(); 3722 3723 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3724 MultiTemplateParamsArg(*this), 3725 /*IsFunctionDefinition=*/true); 3726 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3727} 3728 3729Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3730 if (!D) 3731 return D; 3732 FunctionDecl *FD = 0; 3733 3734 if (FunctionTemplateDecl *FunTmpl 3735 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3736 FD = FunTmpl->getTemplatedDecl(); 3737 else 3738 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3739 3740 CurFunctionNeedsScopeChecking = false; 3741 3742 // See if this is a redefinition. 3743 const FunctionDecl *Definition; 3744 if (FD->getBody(Definition)) { 3745 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3746 Diag(Definition->getLocation(), diag::note_previous_definition); 3747 } 3748 3749 // Builtin functions cannot be defined. 3750 if (unsigned BuiltinID = FD->getBuiltinID()) { 3751 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3752 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3753 FD->setInvalidDecl(); 3754 } 3755 } 3756 3757 // The return type of a function definition must be complete 3758 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3759 QualType ResultType = FD->getResultType(); 3760 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3761 !FD->isInvalidDecl() && 3762 RequireCompleteType(FD->getLocation(), ResultType, 3763 diag::err_func_def_incomplete_result)) 3764 FD->setInvalidDecl(); 3765 3766 // GNU warning -Wmissing-prototypes: 3767 // Warn if a global function is defined without a previous 3768 // prototype declaration. This warning is issued even if the 3769 // definition itself provides a prototype. The aim is to detect 3770 // global functions that fail to be declared in header files. 3771 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3772 !FD->isMain()) { 3773 bool MissingPrototype = true; 3774 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3775 Prev; Prev = Prev->getPreviousDeclaration()) { 3776 // Ignore any declarations that occur in function or method 3777 // scope, because they aren't visible from the header. 3778 if (Prev->getDeclContext()->isFunctionOrMethod()) 3779 continue; 3780 3781 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3782 break; 3783 } 3784 3785 if (MissingPrototype) 3786 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3787 } 3788 3789 if (FnBodyScope) 3790 PushDeclContext(FnBodyScope, FD); 3791 3792 // Check the validity of our function parameters 3793 CheckParmsForFunctionDef(FD); 3794 3795 // Introduce our parameters into the function scope 3796 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3797 ParmVarDecl *Param = FD->getParamDecl(p); 3798 Param->setOwningFunction(FD); 3799 3800 // If this has an identifier, add it to the scope stack. 3801 if (Param->getIdentifier() && FnBodyScope) 3802 PushOnScopeChains(Param, FnBodyScope); 3803 } 3804 3805 // Checking attributes of current function definition 3806 // dllimport attribute. 3807 if (FD->getAttr<DLLImportAttr>() && 3808 (!FD->getAttr<DLLExportAttr>())) { 3809 // dllimport attribute cannot be applied to definition. 3810 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3811 Diag(FD->getLocation(), 3812 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3813 << "dllimport"; 3814 FD->setInvalidDecl(); 3815 return DeclPtrTy::make(FD); 3816 } else { 3817 // If a symbol previously declared dllimport is later defined, the 3818 // attribute is ignored in subsequent references, and a warning is 3819 // emitted. 3820 Diag(FD->getLocation(), 3821 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3822 << FD->getNameAsCString() << "dllimport"; 3823 } 3824 } 3825 return DeclPtrTy::make(FD); 3826} 3827 3828Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3829 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3830} 3831 3832Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3833 bool IsInstantiation) { 3834 Decl *dcl = D.getAs<Decl>(); 3835 Stmt *Body = BodyArg.takeAs<Stmt>(); 3836 3837 FunctionDecl *FD = 0; 3838 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3839 if (FunTmpl) 3840 FD = FunTmpl->getTemplatedDecl(); 3841 else 3842 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3843 3844 if (FD) { 3845 FD->setBody(Body); 3846 if (FD->isMain()) 3847 // C and C++ allow for main to automagically return 0. 3848 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3849 FD->setHasImplicitReturnZero(true); 3850 else 3851 CheckFallThroughForFunctionDef(FD, Body); 3852 3853 if (!FD->isInvalidDecl()) 3854 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3855 3856 // C++ [basic.def.odr]p2: 3857 // [...] A virtual member function is used if it is not pure. [...] 3858 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3859 if (Method->isVirtual() && !Method->isPure()) 3860 MarkDeclarationReferenced(Method->getLocation(), Method); 3861 3862 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3863 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3864 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3865 MD->setBody(Body); 3866 CheckFallThroughForFunctionDef(MD, Body); 3867 MD->setEndLoc(Body->getLocEnd()); 3868 3869 if (!MD->isInvalidDecl()) 3870 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3871 } else { 3872 Body->Destroy(Context); 3873 return DeclPtrTy(); 3874 } 3875 if (!IsInstantiation) 3876 PopDeclContext(); 3877 3878 // Verify and clean out per-function state. 3879 3880 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3881 3882 // Check goto/label use. 3883 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3884 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3885 LabelStmt *L = I->second; 3886 3887 // Verify that we have no forward references left. If so, there was a goto 3888 // or address of a label taken, but no definition of it. Label fwd 3889 // definitions are indicated with a null substmt. 3890 if (L->getSubStmt() != 0) 3891 continue; 3892 3893 // Emit error. 3894 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3895 3896 // At this point, we have gotos that use the bogus label. Stitch it into 3897 // the function body so that they aren't leaked and that the AST is well 3898 // formed. 3899 if (Body == 0) { 3900 // The whole function wasn't parsed correctly, just delete this. 3901 L->Destroy(Context); 3902 continue; 3903 } 3904 3905 // Otherwise, the body is valid: we want to stitch the label decl into the 3906 // function somewhere so that it is properly owned and so that the goto 3907 // has a valid target. Do this by creating a new compound stmt with the 3908 // label in it. 3909 3910 // Give the label a sub-statement. 3911 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3912 3913 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3914 cast<CXXTryStmt>(Body)->getTryBlock() : 3915 cast<CompoundStmt>(Body); 3916 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3917 Elements.push_back(L); 3918 Compound->setStmts(Context, &Elements[0], Elements.size()); 3919 } 3920 FunctionLabelMap.clear(); 3921 3922 if (!Body) return D; 3923 3924 // Verify that that gotos and switch cases don't jump into scopes illegally. 3925 if (CurFunctionNeedsScopeChecking) 3926 DiagnoseInvalidJumps(Body); 3927 3928 // C++ constructors that have function-try-blocks can't have return 3929 // statements in the handlers of that block. (C++ [except.handle]p14) 3930 // Verify this. 3931 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3932 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3933 3934 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3935 computeBaseOrMembersToDestroy(Destructor); 3936 return D; 3937} 3938 3939/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3940/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3941NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3942 IdentifierInfo &II, Scope *S) { 3943 // Before we produce a declaration for an implicitly defined 3944 // function, see whether there was a locally-scoped declaration of 3945 // this name as a function or variable. If so, use that 3946 // (non-visible) declaration, and complain about it. 3947 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3948 = LocallyScopedExternalDecls.find(&II); 3949 if (Pos != LocallyScopedExternalDecls.end()) { 3950 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3951 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3952 return Pos->second; 3953 } 3954 3955 // Extension in C99. Legal in C90, but warn about it. 3956 static const unsigned int BuiltinLen = strlen("__builtin_"); 3957 if (II.getLength() > BuiltinLen && 3958 std::equal(II.getName(), II.getName() + BuiltinLen, "__builtin_")) 3959 Diag(Loc, diag::warn_builtin_unknown) << &II; 3960 else if (getLangOptions().C99) 3961 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3962 else 3963 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3964 3965 // Set a Declarator for the implicit definition: int foo(); 3966 const char *Dummy; 3967 DeclSpec DS; 3968 unsigned DiagID; 3969 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3970 Error = Error; // Silence warning. 3971 assert(!Error && "Error setting up implicit decl!"); 3972 Declarator D(DS, Declarator::BlockContext); 3973 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3974 0, 0, false, SourceLocation(), 3975 false, 0,0,0, Loc, Loc, D), 3976 SourceLocation()); 3977 D.SetIdentifier(&II, Loc); 3978 3979 // Insert this function into translation-unit scope. 3980 3981 DeclContext *PrevDC = CurContext; 3982 CurContext = Context.getTranslationUnitDecl(); 3983 3984 FunctionDecl *FD = 3985 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3986 FD->setImplicit(); 3987 3988 CurContext = PrevDC; 3989 3990 AddKnownFunctionAttributes(FD); 3991 3992 return FD; 3993} 3994 3995/// \brief Adds any function attributes that we know a priori based on 3996/// the declaration of this function. 3997/// 3998/// These attributes can apply both to implicitly-declared builtins 3999/// (like __builtin___printf_chk) or to library-declared functions 4000/// like NSLog or printf. 4001void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4002 if (FD->isInvalidDecl()) 4003 return; 4004 4005 // If this is a built-in function, map its builtin attributes to 4006 // actual attributes. 4007 if (unsigned BuiltinID = FD->getBuiltinID()) { 4008 // Handle printf-formatting attributes. 4009 unsigned FormatIdx; 4010 bool HasVAListArg; 4011 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4012 if (!FD->getAttr<FormatAttr>()) 4013 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4014 HasVAListArg ? 0 : FormatIdx + 2)); 4015 } 4016 4017 // Mark const if we don't care about errno and that is the only 4018 // thing preventing the function from being const. This allows 4019 // IRgen to use LLVM intrinsics for such functions. 4020 if (!getLangOptions().MathErrno && 4021 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4022 if (!FD->getAttr<ConstAttr>()) 4023 FD->addAttr(::new (Context) ConstAttr()); 4024 } 4025 4026 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4027 FD->addAttr(::new (Context) NoReturnAttr()); 4028 } 4029 4030 IdentifierInfo *Name = FD->getIdentifier(); 4031 if (!Name) 4032 return; 4033 if ((!getLangOptions().CPlusPlus && 4034 FD->getDeclContext()->isTranslationUnit()) || 4035 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4036 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4037 LinkageSpecDecl::lang_c)) { 4038 // Okay: this could be a libc/libm/Objective-C function we know 4039 // about. 4040 } else 4041 return; 4042 4043 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4044 // FIXME: NSLog and NSLogv should be target specific 4045 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4046 // FIXME: We known better than our headers. 4047 const_cast<FormatAttr *>(Format)->setType("printf"); 4048 } else 4049 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4050 Name->isStr("NSLogv") ? 0 : 2)); 4051 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4052 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4053 // target-specific builtins, perhaps? 4054 if (!FD->getAttr<FormatAttr>()) 4055 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4056 Name->isStr("vasprintf") ? 0 : 3)); 4057 } 4058} 4059 4060TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 4061 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4062 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4063 4064 // Scope manipulation handled by caller. 4065 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4066 D.getIdentifierLoc(), 4067 D.getIdentifier(), 4068 T); 4069 4070 if (const TagType *TT = T->getAs<TagType>()) { 4071 TagDecl *TD = TT->getDecl(); 4072 4073 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4074 // keep track of the TypedefDecl. 4075 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4076 TD->setTypedefForAnonDecl(NewTD); 4077 } 4078 4079 if (D.isInvalidType()) 4080 NewTD->setInvalidDecl(); 4081 return NewTD; 4082} 4083 4084 4085/// \brief Determine whether a tag with a given kind is acceptable 4086/// as a redeclaration of the given tag declaration. 4087/// 4088/// \returns true if the new tag kind is acceptable, false otherwise. 4089bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4090 TagDecl::TagKind NewTag, 4091 SourceLocation NewTagLoc, 4092 const IdentifierInfo &Name) { 4093 // C++ [dcl.type.elab]p3: 4094 // The class-key or enum keyword present in the 4095 // elaborated-type-specifier shall agree in kind with the 4096 // declaration to which the name in theelaborated-type-specifier 4097 // refers. This rule also applies to the form of 4098 // elaborated-type-specifier that declares a class-name or 4099 // friend class since it can be construed as referring to the 4100 // definition of the class. Thus, in any 4101 // elaborated-type-specifier, the enum keyword shall be used to 4102 // refer to an enumeration (7.2), the union class-keyshall be 4103 // used to refer to a union (clause 9), and either the class or 4104 // struct class-key shall be used to refer to a class (clause 9) 4105 // declared using the class or struct class-key. 4106 TagDecl::TagKind OldTag = Previous->getTagKind(); 4107 if (OldTag == NewTag) 4108 return true; 4109 4110 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4111 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4112 // Warn about the struct/class tag mismatch. 4113 bool isTemplate = false; 4114 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4115 isTemplate = Record->getDescribedClassTemplate(); 4116 4117 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4118 << (NewTag == TagDecl::TK_class) 4119 << isTemplate << &Name 4120 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4121 OldTag == TagDecl::TK_class? "class" : "struct"); 4122 Diag(Previous->getLocation(), diag::note_previous_use); 4123 return true; 4124 } 4125 return false; 4126} 4127 4128/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4129/// former case, Name will be non-null. In the later case, Name will be null. 4130/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4131/// reference/declaration/definition of a tag. 4132Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4133 SourceLocation KWLoc, const CXXScopeSpec &SS, 4134 IdentifierInfo *Name, SourceLocation NameLoc, 4135 AttributeList *Attr, AccessSpecifier AS, 4136 MultiTemplateParamsArg TemplateParameterLists, 4137 bool &OwnedDecl, bool &IsDependent) { 4138 // If this is not a definition, it must have a name. 4139 assert((Name != 0 || TUK == TUK_Definition) && 4140 "Nameless record must be a definition!"); 4141 4142 OwnedDecl = false; 4143 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4144 4145 // FIXME: Check explicit specializations more carefully. 4146 bool isExplicitSpecialization = false; 4147 if (TUK != TUK_Reference) { 4148 if (TemplateParameterList *TemplateParams 4149 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4150 (TemplateParameterList**)TemplateParameterLists.get(), 4151 TemplateParameterLists.size(), 4152 isExplicitSpecialization)) { 4153 if (TemplateParams->size() > 0) { 4154 // This is a declaration or definition of a class template (which may 4155 // be a member of another template). 4156 OwnedDecl = false; 4157 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4158 SS, Name, NameLoc, Attr, 4159 TemplateParams, 4160 AS); 4161 TemplateParameterLists.release(); 4162 return Result.get(); 4163 } else { 4164 // The "template<>" header is extraneous. 4165 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4166 << ElaboratedType::getNameForTagKind(Kind) << Name; 4167 isExplicitSpecialization = true; 4168 } 4169 } 4170 4171 TemplateParameterLists.release(); 4172 } 4173 4174 DeclContext *SearchDC = CurContext; 4175 DeclContext *DC = CurContext; 4176 NamedDecl *PrevDecl = 0; 4177 bool isStdBadAlloc = false; 4178 bool Invalid = false; 4179 4180 if (Name && SS.isNotEmpty()) { 4181 // We have a nested-name tag ('struct foo::bar'). 4182 4183 // Check for invalid 'foo::'. 4184 if (SS.isInvalid()) { 4185 Name = 0; 4186 goto CreateNewDecl; 4187 } 4188 4189 // If this is a friend or a reference to a class in a dependent 4190 // context, don't try to make a decl for it. 4191 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4192 DC = computeDeclContext(SS, false); 4193 if (!DC) { 4194 IsDependent = true; 4195 return DeclPtrTy(); 4196 } 4197 } 4198 4199 if (RequireCompleteDeclContext(SS)) 4200 return DeclPtrTy::make((Decl *)0); 4201 4202 DC = computeDeclContext(SS, true); 4203 SearchDC = DC; 4204 // Look-up name inside 'foo::'. 4205 PrevDecl 4206 = dyn_cast_or_null<TagDecl>( 4207 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 4208 4209 // A tag 'foo::bar' must already exist. 4210 if (PrevDecl == 0) { 4211 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4212 Name = 0; 4213 Invalid = true; 4214 goto CreateNewDecl; 4215 } 4216 } else if (Name) { 4217 // If this is a named struct, check to see if there was a previous forward 4218 // declaration or definition. 4219 // FIXME: We're looking into outer scopes here, even when we 4220 // shouldn't be. Doing so can result in ambiguities that we 4221 // shouldn't be diagnosing. 4222 LookupResult R = LookupName(S, Name, LookupTagName, 4223 /*RedeclarationOnly=*/(TUK != TUK_Reference)); 4224 if (R.isAmbiguous()) { 4225 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4226 // FIXME: This is not best way to recover from case like: 4227 // 4228 // struct S s; 4229 // 4230 // causes needless "incomplete type" error later. 4231 Name = 0; 4232 PrevDecl = 0; 4233 Invalid = true; 4234 } else 4235 PrevDecl = R; 4236 4237 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4238 // FIXME: This makes sure that we ignore the contexts associated 4239 // with C structs, unions, and enums when looking for a matching 4240 // tag declaration or definition. See the similar lookup tweak 4241 // in Sema::LookupName; is there a better way to deal with this? 4242 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4243 SearchDC = SearchDC->getParent(); 4244 } 4245 } 4246 4247 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4248 // Maybe we will complain about the shadowed template parameter. 4249 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4250 // Just pretend that we didn't see the previous declaration. 4251 PrevDecl = 0; 4252 } 4253 4254 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4255 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4256 // This is a declaration of or a reference to "std::bad_alloc". 4257 isStdBadAlloc = true; 4258 4259 if (!PrevDecl && StdBadAlloc) { 4260 // std::bad_alloc has been implicitly declared (but made invisible to 4261 // name lookup). Fill in this implicit declaration as the previous 4262 // declaration, so that the declarations get chained appropriately. 4263 PrevDecl = StdBadAlloc; 4264 } 4265 } 4266 4267 if (PrevDecl) { 4268 // Check whether the previous declaration is usable. 4269 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4270 4271 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4272 // If this is a use of a previous tag, or if the tag is already declared 4273 // in the same scope (so that the definition/declaration completes or 4274 // rementions the tag), reuse the decl. 4275 if (TUK == TUK_Reference || TUK == TUK_Friend || 4276 isDeclInScope(PrevDecl, SearchDC, S)) { 4277 // Make sure that this wasn't declared as an enum and now used as a 4278 // struct or something similar. 4279 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4280 bool SafeToContinue 4281 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4282 Kind != TagDecl::TK_enum); 4283 if (SafeToContinue) 4284 Diag(KWLoc, diag::err_use_with_wrong_tag) 4285 << Name 4286 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4287 PrevTagDecl->getKindName()); 4288 else 4289 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4290 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4291 4292 if (SafeToContinue) 4293 Kind = PrevTagDecl->getTagKind(); 4294 else { 4295 // Recover by making this an anonymous redefinition. 4296 Name = 0; 4297 PrevDecl = 0; 4298 Invalid = true; 4299 } 4300 } 4301 4302 if (!Invalid) { 4303 // If this is a use, just return the declaration we found. 4304 4305 // FIXME: In the future, return a variant or some other clue 4306 // for the consumer of this Decl to know it doesn't own it. 4307 // For our current ASTs this shouldn't be a problem, but will 4308 // need to be changed with DeclGroups. 4309 if (TUK == TUK_Reference || TUK == TUK_Friend) 4310 return DeclPtrTy::make(PrevDecl); 4311 4312 // Diagnose attempts to redefine a tag. 4313 if (TUK == TUK_Definition) { 4314 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4315 Diag(NameLoc, diag::err_redefinition) << Name; 4316 Diag(Def->getLocation(), diag::note_previous_definition); 4317 // If this is a redefinition, recover by making this 4318 // struct be anonymous, which will make any later 4319 // references get the previous definition. 4320 Name = 0; 4321 PrevDecl = 0; 4322 Invalid = true; 4323 } else { 4324 // If the type is currently being defined, complain 4325 // about a nested redefinition. 4326 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4327 if (Tag->isBeingDefined()) { 4328 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4329 Diag(PrevTagDecl->getLocation(), 4330 diag::note_previous_definition); 4331 Name = 0; 4332 PrevDecl = 0; 4333 Invalid = true; 4334 } 4335 } 4336 4337 // Okay, this is definition of a previously declared or referenced 4338 // tag PrevDecl. We're going to create a new Decl for it. 4339 } 4340 } 4341 // If we get here we have (another) forward declaration or we 4342 // have a definition. Just create a new decl. 4343 4344 } else { 4345 // If we get here, this is a definition of a new tag type in a nested 4346 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4347 // new decl/type. We set PrevDecl to NULL so that the entities 4348 // have distinct types. 4349 PrevDecl = 0; 4350 } 4351 // If we get here, we're going to create a new Decl. If PrevDecl 4352 // is non-NULL, it's a definition of the tag declared by 4353 // PrevDecl. If it's NULL, we have a new definition. 4354 } else { 4355 // PrevDecl is a namespace, template, or anything else 4356 // that lives in the IDNS_Tag identifier namespace. 4357 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4358 // The tag name clashes with a namespace name, issue an error and 4359 // recover by making this tag be anonymous. 4360 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4361 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4362 Name = 0; 4363 PrevDecl = 0; 4364 Invalid = true; 4365 } else { 4366 // The existing declaration isn't relevant to us; we're in a 4367 // new scope, so clear out the previous declaration. 4368 PrevDecl = 0; 4369 } 4370 } 4371 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4372 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4373 // C++ [basic.scope.pdecl]p5: 4374 // -- for an elaborated-type-specifier of the form 4375 // 4376 // class-key identifier 4377 // 4378 // if the elaborated-type-specifier is used in the 4379 // decl-specifier-seq or parameter-declaration-clause of a 4380 // function defined in namespace scope, the identifier is 4381 // declared as a class-name in the namespace that contains 4382 // the declaration; otherwise, except as a friend 4383 // declaration, the identifier is declared in the smallest 4384 // non-class, non-function-prototype scope that contains the 4385 // declaration. 4386 // 4387 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4388 // C structs and unions. 4389 // 4390 // GNU C also supports this behavior as part of its incomplete 4391 // enum types extension, while GNU C++ does not. 4392 // 4393 // Find the context where we'll be declaring the tag. 4394 // FIXME: We would like to maintain the current DeclContext as the 4395 // lexical context, 4396 while (SearchDC->isRecord()) 4397 SearchDC = SearchDC->getParent(); 4398 4399 // Find the scope where we'll be declaring the tag. 4400 while (S->isClassScope() || 4401 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4402 ((S->getFlags() & Scope::DeclScope) == 0) || 4403 (S->getEntity() && 4404 ((DeclContext *)S->getEntity())->isTransparentContext())) 4405 S = S->getParent(); 4406 4407 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4408 // C++ [namespace.memdef]p3: 4409 // If a friend declaration in a non-local class first declares a 4410 // class or function, the friend class or function is a member of 4411 // the innermost enclosing namespace. 4412 while (!SearchDC->isFileContext()) 4413 SearchDC = SearchDC->getParent(); 4414 4415 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4416 while (S->getEntity() != SearchDC) 4417 S = S->getParent(); 4418 } 4419 4420CreateNewDecl: 4421 4422 // If there is an identifier, use the location of the identifier as the 4423 // location of the decl, otherwise use the location of the struct/union 4424 // keyword. 4425 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4426 4427 // Otherwise, create a new declaration. If there is a previous 4428 // declaration of the same entity, the two will be linked via 4429 // PrevDecl. 4430 TagDecl *New; 4431 4432 if (Kind == TagDecl::TK_enum) { 4433 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4434 // enum X { A, B, C } D; D should chain to X. 4435 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4436 cast_or_null<EnumDecl>(PrevDecl)); 4437 // If this is an undefined enum, warn. 4438 if (TUK != TUK_Definition && !Invalid) { 4439 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4440 : diag::ext_forward_ref_enum; 4441 Diag(Loc, DK); 4442 } 4443 } else { 4444 // struct/union/class 4445 4446 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4447 // struct X { int A; } D; D should chain to X. 4448 if (getLangOptions().CPlusPlus) { 4449 // FIXME: Look for a way to use RecordDecl for simple structs. 4450 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4451 cast_or_null<CXXRecordDecl>(PrevDecl)); 4452 4453 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4454 StdBadAlloc = cast<CXXRecordDecl>(New); 4455 } else 4456 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4457 cast_or_null<RecordDecl>(PrevDecl)); 4458 } 4459 4460 if (Kind != TagDecl::TK_enum) { 4461 // Handle #pragma pack: if the #pragma pack stack has non-default 4462 // alignment, make up a packed attribute for this decl. These 4463 // attributes are checked when the ASTContext lays out the 4464 // structure. 4465 // 4466 // It is important for implementing the correct semantics that this 4467 // happen here (in act on tag decl). The #pragma pack stack is 4468 // maintained as a result of parser callbacks which can occur at 4469 // many points during the parsing of a struct declaration (because 4470 // the #pragma tokens are effectively skipped over during the 4471 // parsing of the struct). 4472 if (unsigned Alignment = getPragmaPackAlignment()) 4473 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4474 } 4475 4476 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4477 // C++ [dcl.typedef]p3: 4478 // [...] Similarly, in a given scope, a class or enumeration 4479 // shall not be declared with the same name as a typedef-name 4480 // that is declared in that scope and refers to a type other 4481 // than the class or enumeration itself. 4482 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4483 TypedefDecl *PrevTypedef = 0; 4484 if (Lookup.getKind() == LookupResult::Found) 4485 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4486 4487 NamedDecl *PrevTypedefNamed = PrevTypedef; 4488 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4489 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4490 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4491 Diag(Loc, diag::err_tag_definition_of_typedef) 4492 << Context.getTypeDeclType(New) 4493 << PrevTypedef->getUnderlyingType(); 4494 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4495 Invalid = true; 4496 } 4497 } 4498 4499 // If this is a specialization of a member class (of a class template), 4500 // check the specialization. 4501 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4502 Invalid = true; 4503 4504 if (Invalid) 4505 New->setInvalidDecl(); 4506 4507 if (Attr) 4508 ProcessDeclAttributeList(S, New, Attr); 4509 4510 // If we're declaring or defining a tag in function prototype scope 4511 // in C, note that this type can only be used within the function. 4512 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4513 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4514 4515 // Set the lexical context. If the tag has a C++ scope specifier, the 4516 // lexical context will be different from the semantic context. 4517 New->setLexicalDeclContext(CurContext); 4518 4519 // Mark this as a friend decl if applicable. 4520 if (TUK == TUK_Friend) 4521 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4522 4523 // Set the access specifier. 4524 if (!Invalid && TUK != TUK_Friend) 4525 SetMemberAccessSpecifier(New, PrevDecl, AS); 4526 4527 if (TUK == TUK_Definition) 4528 New->startDefinition(); 4529 4530 // If this has an identifier, add it to the scope stack. 4531 if (TUK == TUK_Friend) { 4532 // We might be replacing an existing declaration in the lookup tables; 4533 // if so, borrow its access specifier. 4534 if (PrevDecl) 4535 New->setAccess(PrevDecl->getAccess()); 4536 4537 // Friend tag decls are visible in fairly strange ways. 4538 if (!CurContext->isDependentContext()) { 4539 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4540 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4541 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4542 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4543 } 4544 } else if (Name) { 4545 S = getNonFieldDeclScope(S); 4546 PushOnScopeChains(New, S); 4547 } else { 4548 CurContext->addDecl(New); 4549 } 4550 4551 // If this is the C FILE type, notify the AST context. 4552 if (IdentifierInfo *II = New->getIdentifier()) 4553 if (!New->isInvalidDecl() && 4554 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4555 II->isStr("FILE")) 4556 Context.setFILEDecl(New); 4557 4558 OwnedDecl = true; 4559 return DeclPtrTy::make(New); 4560} 4561 4562void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4563 AdjustDeclIfTemplate(TagD); 4564 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4565 4566 // Enter the tag context. 4567 PushDeclContext(S, Tag); 4568 4569 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4570 FieldCollector->StartClass(); 4571 4572 if (Record->getIdentifier()) { 4573 // C++ [class]p2: 4574 // [...] The class-name is also inserted into the scope of the 4575 // class itself; this is known as the injected-class-name. For 4576 // purposes of access checking, the injected-class-name is treated 4577 // as if it were a public member name. 4578 CXXRecordDecl *InjectedClassName 4579 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4580 CurContext, Record->getLocation(), 4581 Record->getIdentifier(), 4582 Record->getTagKeywordLoc(), 4583 Record); 4584 InjectedClassName->setImplicit(); 4585 InjectedClassName->setAccess(AS_public); 4586 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4587 InjectedClassName->setDescribedClassTemplate(Template); 4588 PushOnScopeChains(InjectedClassName, S); 4589 assert(InjectedClassName->isInjectedClassName() && 4590 "Broken injected-class-name"); 4591 } 4592 } 4593} 4594 4595void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4596 SourceLocation RBraceLoc) { 4597 AdjustDeclIfTemplate(TagD); 4598 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4599 Tag->setRBraceLoc(RBraceLoc); 4600 4601 if (isa<CXXRecordDecl>(Tag)) 4602 FieldCollector->FinishClass(); 4603 4604 // Exit this scope of this tag's definition. 4605 PopDeclContext(); 4606 4607 // Notify the consumer that we've defined a tag. 4608 Consumer.HandleTagDeclDefinition(Tag); 4609} 4610 4611// Note that FieldName may be null for anonymous bitfields. 4612bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4613 QualType FieldTy, const Expr *BitWidth, 4614 bool *ZeroWidth) { 4615 // Default to true; that shouldn't confuse checks for emptiness 4616 if (ZeroWidth) 4617 *ZeroWidth = true; 4618 4619 // C99 6.7.2.1p4 - verify the field type. 4620 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4621 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4622 // Handle incomplete types with specific error. 4623 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4624 return true; 4625 if (FieldName) 4626 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4627 << FieldName << FieldTy << BitWidth->getSourceRange(); 4628 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4629 << FieldTy << BitWidth->getSourceRange(); 4630 } 4631 4632 // If the bit-width is type- or value-dependent, don't try to check 4633 // it now. 4634 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4635 return false; 4636 4637 llvm::APSInt Value; 4638 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4639 return true; 4640 4641 if (Value != 0 && ZeroWidth) 4642 *ZeroWidth = false; 4643 4644 // Zero-width bitfield is ok for anonymous field. 4645 if (Value == 0 && FieldName) 4646 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4647 4648 if (Value.isSigned() && Value.isNegative()) { 4649 if (FieldName) 4650 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4651 << FieldName << Value.toString(10); 4652 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4653 << Value.toString(10); 4654 } 4655 4656 if (!FieldTy->isDependentType()) { 4657 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4658 if (Value.getZExtValue() > TypeSize) { 4659 if (FieldName) 4660 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4661 << FieldName << (unsigned)TypeSize; 4662 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4663 << (unsigned)TypeSize; 4664 } 4665 } 4666 4667 return false; 4668} 4669 4670/// ActOnField - Each field of a struct/union/class is passed into this in order 4671/// to create a FieldDecl object for it. 4672Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4673 SourceLocation DeclStart, 4674 Declarator &D, ExprTy *BitfieldWidth) { 4675 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4676 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4677 AS_public); 4678 return DeclPtrTy::make(Res); 4679} 4680 4681/// HandleField - Analyze a field of a C struct or a C++ data member. 4682/// 4683FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4684 SourceLocation DeclStart, 4685 Declarator &D, Expr *BitWidth, 4686 AccessSpecifier AS) { 4687 IdentifierInfo *II = D.getIdentifier(); 4688 SourceLocation Loc = DeclStart; 4689 if (II) Loc = D.getIdentifierLoc(); 4690 4691 DeclaratorInfo *DInfo = 0; 4692 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4693 if (getLangOptions().CPlusPlus) 4694 CheckExtraCXXDefaultArguments(D); 4695 4696 DiagnoseFunctionSpecifiers(D); 4697 4698 if (D.getDeclSpec().isThreadSpecified()) 4699 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4700 4701 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4702 4703 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4704 // Maybe we will complain about the shadowed template parameter. 4705 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4706 // Just pretend that we didn't see the previous declaration. 4707 PrevDecl = 0; 4708 } 4709 4710 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4711 PrevDecl = 0; 4712 4713 bool Mutable 4714 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4715 SourceLocation TSSL = D.getSourceRange().getBegin(); 4716 FieldDecl *NewFD 4717 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4718 AS, PrevDecl, &D); 4719 if (NewFD->isInvalidDecl() && PrevDecl) { 4720 // Don't introduce NewFD into scope; there's already something 4721 // with the same name in the same scope. 4722 } else if (II) { 4723 PushOnScopeChains(NewFD, S); 4724 } else 4725 Record->addDecl(NewFD); 4726 4727 return NewFD; 4728} 4729 4730/// \brief Build a new FieldDecl and check its well-formedness. 4731/// 4732/// This routine builds a new FieldDecl given the fields name, type, 4733/// record, etc. \p PrevDecl should refer to any previous declaration 4734/// with the same name and in the same scope as the field to be 4735/// created. 4736/// 4737/// \returns a new FieldDecl. 4738/// 4739/// \todo The Declarator argument is a hack. It will be removed once 4740FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4741 DeclaratorInfo *DInfo, 4742 RecordDecl *Record, SourceLocation Loc, 4743 bool Mutable, Expr *BitWidth, 4744 SourceLocation TSSL, 4745 AccessSpecifier AS, NamedDecl *PrevDecl, 4746 Declarator *D) { 4747 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4748 bool InvalidDecl = false; 4749 if (D) InvalidDecl = D->isInvalidType(); 4750 4751 // If we receive a broken type, recover by assuming 'int' and 4752 // marking this declaration as invalid. 4753 if (T.isNull()) { 4754 InvalidDecl = true; 4755 T = Context.IntTy; 4756 } 4757 4758 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4759 // than a variably modified type. 4760 if (T->isVariablyModifiedType()) { 4761 bool SizeIsNegative; 4762 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4763 SizeIsNegative); 4764 if (!FixedTy.isNull()) { 4765 Diag(Loc, diag::warn_illegal_constant_array_size); 4766 T = FixedTy; 4767 } else { 4768 if (SizeIsNegative) 4769 Diag(Loc, diag::err_typecheck_negative_array_size); 4770 else 4771 Diag(Loc, diag::err_typecheck_field_variable_size); 4772 InvalidDecl = true; 4773 } 4774 } 4775 4776 // Fields can not have abstract class types 4777 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4778 AbstractFieldType)) 4779 InvalidDecl = true; 4780 4781 bool ZeroWidth = false; 4782 // If this is declared as a bit-field, check the bit-field. 4783 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4784 InvalidDecl = true; 4785 DeleteExpr(BitWidth); 4786 BitWidth = 0; 4787 ZeroWidth = false; 4788 } 4789 4790 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4791 BitWidth, Mutable); 4792 if (InvalidDecl) 4793 NewFD->setInvalidDecl(); 4794 4795 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4796 Diag(Loc, diag::err_duplicate_member) << II; 4797 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4798 NewFD->setInvalidDecl(); 4799 } 4800 4801 if (getLangOptions().CPlusPlus) { 4802 QualType EltTy = Context.getBaseElementType(T); 4803 4804 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4805 4806 if (!T->isPODType()) 4807 CXXRecord->setPOD(false); 4808 if (!ZeroWidth) 4809 CXXRecord->setEmpty(false); 4810 4811 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4812 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4813 4814 if (!RDecl->hasTrivialConstructor()) 4815 CXXRecord->setHasTrivialConstructor(false); 4816 if (!RDecl->hasTrivialCopyConstructor()) 4817 CXXRecord->setHasTrivialCopyConstructor(false); 4818 if (!RDecl->hasTrivialCopyAssignment()) 4819 CXXRecord->setHasTrivialCopyAssignment(false); 4820 if (!RDecl->hasTrivialDestructor()) 4821 CXXRecord->setHasTrivialDestructor(false); 4822 4823 // C++ 9.5p1: An object of a class with a non-trivial 4824 // constructor, a non-trivial copy constructor, a non-trivial 4825 // destructor, or a non-trivial copy assignment operator 4826 // cannot be a member of a union, nor can an array of such 4827 // objects. 4828 // TODO: C++0x alters this restriction significantly. 4829 if (Record->isUnion()) { 4830 // We check for copy constructors before constructors 4831 // because otherwise we'll never get complaints about 4832 // copy constructors. 4833 4834 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4835 4836 CXXSpecialMember member; 4837 if (!RDecl->hasTrivialCopyConstructor()) 4838 member = CXXCopyConstructor; 4839 else if (!RDecl->hasTrivialConstructor()) 4840 member = CXXDefaultConstructor; 4841 else if (!RDecl->hasTrivialCopyAssignment()) 4842 member = CXXCopyAssignment; 4843 else if (!RDecl->hasTrivialDestructor()) 4844 member = CXXDestructor; 4845 else 4846 member = invalid; 4847 4848 if (member != invalid) { 4849 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4850 DiagnoseNontrivial(RT, member); 4851 NewFD->setInvalidDecl(); 4852 } 4853 } 4854 } 4855 } 4856 4857 // FIXME: We need to pass in the attributes given an AST 4858 // representation, not a parser representation. 4859 if (D) 4860 // FIXME: What to pass instead of TUScope? 4861 ProcessDeclAttributes(TUScope, NewFD, *D); 4862 4863 if (T.isObjCGCWeak()) 4864 Diag(Loc, diag::warn_attribute_weak_on_field); 4865 4866 NewFD->setAccess(AS); 4867 4868 // C++ [dcl.init.aggr]p1: 4869 // An aggregate is an array or a class (clause 9) with [...] no 4870 // private or protected non-static data members (clause 11). 4871 // A POD must be an aggregate. 4872 if (getLangOptions().CPlusPlus && 4873 (AS == AS_private || AS == AS_protected)) { 4874 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4875 CXXRecord->setAggregate(false); 4876 CXXRecord->setPOD(false); 4877 } 4878 4879 return NewFD; 4880} 4881 4882/// DiagnoseNontrivial - Given that a class has a non-trivial 4883/// special member, figure out why. 4884void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4885 QualType QT(T, 0U); 4886 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4887 4888 // Check whether the member was user-declared. 4889 switch (member) { 4890 case CXXDefaultConstructor: 4891 if (RD->hasUserDeclaredConstructor()) { 4892 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4893 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4894 if (!ci->isImplicitlyDefined(Context)) { 4895 SourceLocation CtorLoc = ci->getLocation(); 4896 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4897 return; 4898 } 4899 4900 assert(0 && "found no user-declared constructors"); 4901 return; 4902 } 4903 break; 4904 4905 case CXXCopyConstructor: 4906 if (RD->hasUserDeclaredCopyConstructor()) { 4907 SourceLocation CtorLoc = 4908 RD->getCopyConstructor(Context, 0)->getLocation(); 4909 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4910 return; 4911 } 4912 break; 4913 4914 case CXXCopyAssignment: 4915 if (RD->hasUserDeclaredCopyAssignment()) { 4916 // FIXME: this should use the location of the copy 4917 // assignment, not the type. 4918 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4919 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4920 return; 4921 } 4922 break; 4923 4924 case CXXDestructor: 4925 if (RD->hasUserDeclaredDestructor()) { 4926 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4927 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4928 return; 4929 } 4930 break; 4931 } 4932 4933 typedef CXXRecordDecl::base_class_iterator base_iter; 4934 4935 // Virtual bases and members inhibit trivial copying/construction, 4936 // but not trivial destruction. 4937 if (member != CXXDestructor) { 4938 // Check for virtual bases. vbases includes indirect virtual bases, 4939 // so we just iterate through the direct bases. 4940 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4941 if (bi->isVirtual()) { 4942 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4943 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4944 return; 4945 } 4946 4947 // Check for virtual methods. 4948 typedef CXXRecordDecl::method_iterator meth_iter; 4949 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4950 ++mi) { 4951 if (mi->isVirtual()) { 4952 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4953 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4954 return; 4955 } 4956 } 4957 } 4958 4959 bool (CXXRecordDecl::*hasTrivial)() const; 4960 switch (member) { 4961 case CXXDefaultConstructor: 4962 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4963 case CXXCopyConstructor: 4964 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4965 case CXXCopyAssignment: 4966 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4967 case CXXDestructor: 4968 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4969 default: 4970 assert(0 && "unexpected special member"); return; 4971 } 4972 4973 // Check for nontrivial bases (and recurse). 4974 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4975 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 4976 assert(BaseRT); 4977 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4978 if (!(BaseRecTy->*hasTrivial)()) { 4979 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4980 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4981 DiagnoseNontrivial(BaseRT, member); 4982 return; 4983 } 4984 } 4985 4986 // Check for nontrivial members (and recurse). 4987 typedef RecordDecl::field_iterator field_iter; 4988 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4989 ++fi) { 4990 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4991 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 4992 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4993 4994 if (!(EltRD->*hasTrivial)()) { 4995 SourceLocation FLoc = (*fi)->getLocation(); 4996 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4997 DiagnoseNontrivial(EltRT, member); 4998 return; 4999 } 5000 } 5001 } 5002 5003 assert(0 && "found no explanation for non-trivial member"); 5004} 5005 5006/// TranslateIvarVisibility - Translate visibility from a token ID to an 5007/// AST enum value. 5008static ObjCIvarDecl::AccessControl 5009TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5010 switch (ivarVisibility) { 5011 default: assert(0 && "Unknown visitibility kind"); 5012 case tok::objc_private: return ObjCIvarDecl::Private; 5013 case tok::objc_public: return ObjCIvarDecl::Public; 5014 case tok::objc_protected: return ObjCIvarDecl::Protected; 5015 case tok::objc_package: return ObjCIvarDecl::Package; 5016 } 5017} 5018 5019/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5020/// in order to create an IvarDecl object for it. 5021Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5022 SourceLocation DeclStart, 5023 DeclPtrTy IntfDecl, 5024 Declarator &D, ExprTy *BitfieldWidth, 5025 tok::ObjCKeywordKind Visibility) { 5026 5027 IdentifierInfo *II = D.getIdentifier(); 5028 Expr *BitWidth = (Expr*)BitfieldWidth; 5029 SourceLocation Loc = DeclStart; 5030 if (II) Loc = D.getIdentifierLoc(); 5031 5032 // FIXME: Unnamed fields can be handled in various different ways, for 5033 // example, unnamed unions inject all members into the struct namespace! 5034 5035 DeclaratorInfo *DInfo = 0; 5036 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5037 5038 if (BitWidth) { 5039 // 6.7.2.1p3, 6.7.2.1p4 5040 if (VerifyBitField(Loc, II, T, BitWidth)) { 5041 D.setInvalidType(); 5042 DeleteExpr(BitWidth); 5043 BitWidth = 0; 5044 } 5045 } else { 5046 // Not a bitfield. 5047 5048 // validate II. 5049 5050 } 5051 5052 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5053 // than a variably modified type. 5054 if (T->isVariablyModifiedType()) { 5055 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5056 D.setInvalidType(); 5057 } 5058 5059 // Get the visibility (access control) for this ivar. 5060 ObjCIvarDecl::AccessControl ac = 5061 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5062 : ObjCIvarDecl::None; 5063 // Must set ivar's DeclContext to its enclosing interface. 5064 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5065 DeclContext *EnclosingContext; 5066 if (ObjCImplementationDecl *IMPDecl = 5067 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5068 // Case of ivar declared in an implementation. Context is that of its class. 5069 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5070 assert(IDecl && "No class- ActOnIvar"); 5071 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5072 } else 5073 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5074 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5075 5076 // Construct the decl. 5077 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5078 EnclosingContext, Loc, II, T, 5079 DInfo, ac, (Expr *)BitfieldWidth); 5080 5081 if (II) { 5082 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 5083 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5084 && !isa<TagDecl>(PrevDecl)) { 5085 Diag(Loc, diag::err_duplicate_member) << II; 5086 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5087 NewID->setInvalidDecl(); 5088 } 5089 } 5090 5091 // Process attributes attached to the ivar. 5092 ProcessDeclAttributes(S, NewID, D); 5093 5094 if (D.isInvalidType()) 5095 NewID->setInvalidDecl(); 5096 5097 if (II) { 5098 // FIXME: When interfaces are DeclContexts, we'll need to add 5099 // these to the interface. 5100 S->AddDecl(DeclPtrTy::make(NewID)); 5101 IdResolver.AddDecl(NewID); 5102 } 5103 5104 return DeclPtrTy::make(NewID); 5105} 5106 5107void Sema::ActOnFields(Scope* S, 5108 SourceLocation RecLoc, DeclPtrTy RecDecl, 5109 DeclPtrTy *Fields, unsigned NumFields, 5110 SourceLocation LBrac, SourceLocation RBrac, 5111 AttributeList *Attr) { 5112 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5113 assert(EnclosingDecl && "missing record or interface decl"); 5114 5115 // If the decl this is being inserted into is invalid, then it may be a 5116 // redeclaration or some other bogus case. Don't try to add fields to it. 5117 if (EnclosingDecl->isInvalidDecl()) { 5118 // FIXME: Deallocate fields? 5119 return; 5120 } 5121 5122 5123 // Verify that all the fields are okay. 5124 unsigned NumNamedMembers = 0; 5125 llvm::SmallVector<FieldDecl*, 32> RecFields; 5126 5127 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5128 for (unsigned i = 0; i != NumFields; ++i) { 5129 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5130 5131 // Get the type for the field. 5132 Type *FDTy = FD->getType().getTypePtr(); 5133 5134 if (!FD->isAnonymousStructOrUnion()) { 5135 // Remember all fields written by the user. 5136 RecFields.push_back(FD); 5137 } 5138 5139 // If the field is already invalid for some reason, don't emit more 5140 // diagnostics about it. 5141 if (FD->isInvalidDecl()) 5142 continue; 5143 5144 // C99 6.7.2.1p2: 5145 // A structure or union shall not contain a member with 5146 // incomplete or function type (hence, a structure shall not 5147 // contain an instance of itself, but may contain a pointer to 5148 // an instance of itself), except that the last member of a 5149 // structure with more than one named member may have incomplete 5150 // array type; such a structure (and any union containing, 5151 // possibly recursively, a member that is such a structure) 5152 // shall not be a member of a structure or an element of an 5153 // array. 5154 if (FDTy->isFunctionType()) { 5155 // Field declared as a function. 5156 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5157 << FD->getDeclName(); 5158 FD->setInvalidDecl(); 5159 EnclosingDecl->setInvalidDecl(); 5160 continue; 5161 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5162 Record && Record->isStruct()) { 5163 // Flexible array member. 5164 if (NumNamedMembers < 1) { 5165 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5166 << FD->getDeclName(); 5167 FD->setInvalidDecl(); 5168 EnclosingDecl->setInvalidDecl(); 5169 continue; 5170 } 5171 // Okay, we have a legal flexible array member at the end of the struct. 5172 if (Record) 5173 Record->setHasFlexibleArrayMember(true); 5174 } else if (!FDTy->isDependentType() && 5175 RequireCompleteType(FD->getLocation(), FD->getType(), 5176 diag::err_field_incomplete)) { 5177 // Incomplete type 5178 FD->setInvalidDecl(); 5179 EnclosingDecl->setInvalidDecl(); 5180 continue; 5181 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5182 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5183 // If this is a member of a union, then entire union becomes "flexible". 5184 if (Record && Record->isUnion()) { 5185 Record->setHasFlexibleArrayMember(true); 5186 } else { 5187 // If this is a struct/class and this is not the last element, reject 5188 // it. Note that GCC supports variable sized arrays in the middle of 5189 // structures. 5190 if (i != NumFields-1) 5191 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5192 << FD->getDeclName() << FD->getType(); 5193 else { 5194 // We support flexible arrays at the end of structs in 5195 // other structs as an extension. 5196 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5197 << FD->getDeclName(); 5198 if (Record) 5199 Record->setHasFlexibleArrayMember(true); 5200 } 5201 } 5202 } 5203 if (Record && FDTTy->getDecl()->hasObjectMember()) 5204 Record->setHasObjectMember(true); 5205 } else if (FDTy->isObjCInterfaceType()) { 5206 /// A field cannot be an Objective-c object 5207 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5208 FD->setInvalidDecl(); 5209 EnclosingDecl->setInvalidDecl(); 5210 continue; 5211 } else if (getLangOptions().ObjC1 && 5212 getLangOptions().getGCMode() != LangOptions::NonGC && 5213 Record && 5214 (FD->getType()->isObjCObjectPointerType() || 5215 FD->getType().isObjCGCStrong())) 5216 Record->setHasObjectMember(true); 5217 // Keep track of the number of named members. 5218 if (FD->getIdentifier()) 5219 ++NumNamedMembers; 5220 } 5221 5222 // Okay, we successfully defined 'Record'. 5223 if (Record) { 5224 Record->completeDefinition(Context); 5225 } else { 5226 ObjCIvarDecl **ClsFields = 5227 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5228 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5229 ID->setIVarList(ClsFields, RecFields.size(), Context); 5230 ID->setLocEnd(RBrac); 5231 // Add ivar's to class's DeclContext. 5232 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5233 ClsFields[i]->setLexicalDeclContext(ID); 5234 ID->addDecl(ClsFields[i]); 5235 } 5236 // Must enforce the rule that ivars in the base classes may not be 5237 // duplicates. 5238 if (ID->getSuperClass()) { 5239 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5240 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5241 ObjCIvarDecl* Ivar = (*IVI); 5242 5243 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5244 ObjCIvarDecl* prevIvar = 5245 ID->getSuperClass()->lookupInstanceVariable(II); 5246 if (prevIvar) { 5247 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5248 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5249 } 5250 } 5251 } 5252 } 5253 } else if (ObjCImplementationDecl *IMPDecl = 5254 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5255 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5256 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5257 // Ivar declared in @implementation never belongs to the implementation. 5258 // Only it is in implementation's lexical context. 5259 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5260 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5261 } 5262 } 5263 5264 if (Attr) 5265 ProcessDeclAttributeList(S, Record, Attr); 5266} 5267 5268EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5269 EnumConstantDecl *LastEnumConst, 5270 SourceLocation IdLoc, 5271 IdentifierInfo *Id, 5272 ExprArg val) { 5273 Expr *Val = (Expr *)val.get(); 5274 5275 llvm::APSInt EnumVal(32); 5276 QualType EltTy; 5277 if (Val && !Val->isTypeDependent()) { 5278 // Make sure to promote the operand type to int. 5279 UsualUnaryConversions(Val); 5280 if (Val != val.get()) { 5281 val.release(); 5282 val = Val; 5283 } 5284 5285 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5286 SourceLocation ExpLoc; 5287 if (!Val->isValueDependent() && 5288 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5289 Val = 0; 5290 } else { 5291 EltTy = Val->getType(); 5292 } 5293 } 5294 5295 if (!Val) { 5296 if (LastEnumConst) { 5297 // Assign the last value + 1. 5298 EnumVal = LastEnumConst->getInitVal(); 5299 ++EnumVal; 5300 5301 // Check for overflow on increment. 5302 if (EnumVal < LastEnumConst->getInitVal()) 5303 Diag(IdLoc, diag::warn_enum_value_overflow); 5304 5305 EltTy = LastEnumConst->getType(); 5306 } else { 5307 // First value, set to zero. 5308 EltTy = Context.IntTy; 5309 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5310 } 5311 } 5312 5313 val.release(); 5314 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5315 Val, EnumVal); 5316} 5317 5318 5319Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5320 DeclPtrTy lastEnumConst, 5321 SourceLocation IdLoc, 5322 IdentifierInfo *Id, 5323 SourceLocation EqualLoc, ExprTy *val) { 5324 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5325 EnumConstantDecl *LastEnumConst = 5326 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5327 Expr *Val = static_cast<Expr*>(val); 5328 5329 // The scope passed in may not be a decl scope. Zip up the scope tree until 5330 // we find one that is. 5331 S = getNonFieldDeclScope(S); 5332 5333 // Verify that there isn't already something declared with this name in this 5334 // scope. 5335 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 5336 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5337 // Maybe we will complain about the shadowed template parameter. 5338 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5339 // Just pretend that we didn't see the previous declaration. 5340 PrevDecl = 0; 5341 } 5342 5343 if (PrevDecl) { 5344 // When in C++, we may get a TagDecl with the same name; in this case the 5345 // enum constant will 'hide' the tag. 5346 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5347 "Received TagDecl when not in C++!"); 5348 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5349 if (isa<EnumConstantDecl>(PrevDecl)) 5350 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5351 else 5352 Diag(IdLoc, diag::err_redefinition) << Id; 5353 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5354 if (Val) Val->Destroy(Context); 5355 return DeclPtrTy(); 5356 } 5357 } 5358 5359 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5360 IdLoc, Id, Owned(Val)); 5361 5362 // Register this decl in the current scope stack. 5363 if (New) 5364 PushOnScopeChains(New, S); 5365 5366 return DeclPtrTy::make(New); 5367} 5368 5369void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5370 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5371 DeclPtrTy *Elements, unsigned NumElements, 5372 Scope *S, AttributeList *Attr) { 5373 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5374 QualType EnumType = Context.getTypeDeclType(Enum); 5375 5376 if (Attr) 5377 ProcessDeclAttributeList(S, Enum, Attr); 5378 5379 // TODO: If the result value doesn't fit in an int, it must be a long or long 5380 // long value. ISO C does not support this, but GCC does as an extension, 5381 // emit a warning. 5382 unsigned IntWidth = Context.Target.getIntWidth(); 5383 unsigned CharWidth = Context.Target.getCharWidth(); 5384 unsigned ShortWidth = Context.Target.getShortWidth(); 5385 5386 // Verify that all the values are okay, compute the size of the values, and 5387 // reverse the list. 5388 unsigned NumNegativeBits = 0; 5389 unsigned NumPositiveBits = 0; 5390 5391 // Keep track of whether all elements have type int. 5392 bool AllElementsInt = true; 5393 5394 for (unsigned i = 0; i != NumElements; ++i) { 5395 EnumConstantDecl *ECD = 5396 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5397 if (!ECD) continue; // Already issued a diagnostic. 5398 5399 // If the enum value doesn't fit in an int, emit an extension warning. 5400 const llvm::APSInt &InitVal = ECD->getInitVal(); 5401 assert(InitVal.getBitWidth() >= IntWidth && 5402 "Should have promoted value to int"); 5403 if (InitVal.getBitWidth() > IntWidth) { 5404 llvm::APSInt V(InitVal); 5405 V.trunc(IntWidth); 5406 V.extend(InitVal.getBitWidth()); 5407 if (V != InitVal) 5408 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5409 << InitVal.toString(10); 5410 } 5411 5412 // Keep track of the size of positive and negative values. 5413 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5414 NumPositiveBits = std::max(NumPositiveBits, 5415 (unsigned)InitVal.getActiveBits()); 5416 else 5417 NumNegativeBits = std::max(NumNegativeBits, 5418 (unsigned)InitVal.getMinSignedBits()); 5419 5420 // Keep track of whether every enum element has type int (very commmon). 5421 if (AllElementsInt) 5422 AllElementsInt = ECD->getType() == Context.IntTy; 5423 } 5424 5425 // Figure out the type that should be used for this enum. 5426 // FIXME: Support -fshort-enums. 5427 QualType BestType; 5428 unsigned BestWidth; 5429 5430 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5431 5432 if (NumNegativeBits) { 5433 // If there is a negative value, figure out the smallest integer type (of 5434 // int/long/longlong) that fits. 5435 // If it's packed, check also if it fits a char or a short. 5436 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5437 BestType = Context.SignedCharTy; 5438 BestWidth = CharWidth; 5439 } else if (Packed && NumNegativeBits <= ShortWidth && 5440 NumPositiveBits < ShortWidth) { 5441 BestType = Context.ShortTy; 5442 BestWidth = ShortWidth; 5443 } 5444 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5445 BestType = Context.IntTy; 5446 BestWidth = IntWidth; 5447 } else { 5448 BestWidth = Context.Target.getLongWidth(); 5449 5450 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5451 BestType = Context.LongTy; 5452 else { 5453 BestWidth = Context.Target.getLongLongWidth(); 5454 5455 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5456 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5457 BestType = Context.LongLongTy; 5458 } 5459 } 5460 } else { 5461 // If there is no negative value, figure out which of uint, ulong, ulonglong 5462 // fits. 5463 // If it's packed, check also if it fits a char or a short. 5464 if (Packed && NumPositiveBits <= CharWidth) { 5465 BestType = Context.UnsignedCharTy; 5466 BestWidth = CharWidth; 5467 } else if (Packed && NumPositiveBits <= ShortWidth) { 5468 BestType = Context.UnsignedShortTy; 5469 BestWidth = ShortWidth; 5470 } 5471 else if (NumPositiveBits <= IntWidth) { 5472 BestType = Context.UnsignedIntTy; 5473 BestWidth = IntWidth; 5474 } else if (NumPositiveBits <= 5475 (BestWidth = Context.Target.getLongWidth())) { 5476 BestType = Context.UnsignedLongTy; 5477 } else { 5478 BestWidth = Context.Target.getLongLongWidth(); 5479 assert(NumPositiveBits <= BestWidth && 5480 "How could an initializer get larger than ULL?"); 5481 BestType = Context.UnsignedLongLongTy; 5482 } 5483 } 5484 5485 // Loop over all of the enumerator constants, changing their types to match 5486 // the type of the enum if needed. 5487 for (unsigned i = 0; i != NumElements; ++i) { 5488 EnumConstantDecl *ECD = 5489 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5490 if (!ECD) continue; // Already issued a diagnostic. 5491 5492 // Standard C says the enumerators have int type, but we allow, as an 5493 // extension, the enumerators to be larger than int size. If each 5494 // enumerator value fits in an int, type it as an int, otherwise type it the 5495 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5496 // that X has type 'int', not 'unsigned'. 5497 if (ECD->getType() == Context.IntTy) { 5498 // Make sure the init value is signed. 5499 llvm::APSInt IV = ECD->getInitVal(); 5500 IV.setIsSigned(true); 5501 ECD->setInitVal(IV); 5502 5503 if (getLangOptions().CPlusPlus) 5504 // C++ [dcl.enum]p4: Following the closing brace of an 5505 // enum-specifier, each enumerator has the type of its 5506 // enumeration. 5507 ECD->setType(EnumType); 5508 continue; // Already int type. 5509 } 5510 5511 // Determine whether the value fits into an int. 5512 llvm::APSInt InitVal = ECD->getInitVal(); 5513 bool FitsInInt; 5514 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5515 FitsInInt = InitVal.getActiveBits() < IntWidth; 5516 else 5517 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5518 5519 // If it fits into an integer type, force it. Otherwise force it to match 5520 // the enum decl type. 5521 QualType NewTy; 5522 unsigned NewWidth; 5523 bool NewSign; 5524 if (FitsInInt) { 5525 NewTy = Context.IntTy; 5526 NewWidth = IntWidth; 5527 NewSign = true; 5528 } else if (ECD->getType() == BestType) { 5529 // Already the right type! 5530 if (getLangOptions().CPlusPlus) 5531 // C++ [dcl.enum]p4: Following the closing brace of an 5532 // enum-specifier, each enumerator has the type of its 5533 // enumeration. 5534 ECD->setType(EnumType); 5535 continue; 5536 } else { 5537 NewTy = BestType; 5538 NewWidth = BestWidth; 5539 NewSign = BestType->isSignedIntegerType(); 5540 } 5541 5542 // Adjust the APSInt value. 5543 InitVal.extOrTrunc(NewWidth); 5544 InitVal.setIsSigned(NewSign); 5545 ECD->setInitVal(InitVal); 5546 5547 // Adjust the Expr initializer and type. 5548 if (ECD->getInitExpr()) 5549 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5550 CastExpr::CK_Unknown, 5551 ECD->getInitExpr(), 5552 /*isLvalue=*/false)); 5553 if (getLangOptions().CPlusPlus) 5554 // C++ [dcl.enum]p4: Following the closing brace of an 5555 // enum-specifier, each enumerator has the type of its 5556 // enumeration. 5557 ECD->setType(EnumType); 5558 else 5559 ECD->setType(NewTy); 5560 } 5561 5562 Enum->completeDefinition(Context, BestType); 5563} 5564 5565Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5566 ExprArg expr) { 5567 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5568 5569 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5570 Loc, AsmString); 5571 CurContext->addDecl(New); 5572 return DeclPtrTy::make(New); 5573} 5574 5575void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5576 SourceLocation PragmaLoc, 5577 SourceLocation NameLoc) { 5578 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5579 5580 if (PrevDecl) { 5581 PrevDecl->addAttr(::new (Context) WeakAttr()); 5582 } else { 5583 (void)WeakUndeclaredIdentifiers.insert( 5584 std::pair<IdentifierInfo*,WeakInfo> 5585 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5586 } 5587} 5588 5589void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5590 IdentifierInfo* AliasName, 5591 SourceLocation PragmaLoc, 5592 SourceLocation NameLoc, 5593 SourceLocation AliasNameLoc) { 5594 Decl *PrevDecl = LookupName(TUScope, AliasName, LookupOrdinaryName); 5595 WeakInfo W = WeakInfo(Name, NameLoc); 5596 5597 if (PrevDecl) { 5598 if (!PrevDecl->hasAttr<AliasAttr>()) 5599 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5600 DeclApplyPragmaWeak(TUScope, ND, W); 5601 } else { 5602 (void)WeakUndeclaredIdentifiers.insert( 5603 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5604 } 5605} 5606