SemaDecl.cpp revision 0feecbb3165b06ff34663a8c233316aaf7f84ce1
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Basic/TargetInfo.h" 27#include "clang/Basic/SourceManager.h" 28// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 29#include "clang/Lex/Preprocessor.h" 30#include "clang/Lex/HeaderSearch.h" 31#include "llvm/ADT/BitVector.h" 32#include "llvm/ADT/SmallSet.h" 33#include "llvm/ADT/STLExtras.h" 34#include <algorithm> 35#include <functional> 36#include <queue> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, const CXXScopeSpec *SS) { 65 // C++ [temp.res]p3: 66 // A qualified-id that refers to a type and in which the 67 // nested-name-specifier depends on a template-parameter (14.6.2) 68 // shall be prefixed by the keyword typename to indicate that the 69 // qualified-id denotes a type, forming an 70 // elaborated-type-specifier (7.1.5.3). 71 // 72 // We therefore do not perform any name lookup if the result would 73 // refer to a member of an unknown specialization. 74 if (SS && isUnknownSpecialization(*SS)) 75 return 0; 76 77 LookupResult Result 78 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 79 80 NamedDecl *IIDecl = 0; 81 switch (Result.getKind()) { 82 case LookupResult::NotFound: 83 case LookupResult::FoundOverloaded: 84 return 0; 85 86 case LookupResult::AmbiguousBaseSubobjectTypes: 87 case LookupResult::AmbiguousBaseSubobjects: 88 case LookupResult::AmbiguousReference: { 89 // Look to see if we have a type anywhere in the list of results. 90 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 91 Res != ResEnd; ++Res) { 92 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 93 if (!IIDecl || 94 (*Res)->getLocation().getRawEncoding() < 95 IIDecl->getLocation().getRawEncoding()) 96 IIDecl = *Res; 97 } 98 } 99 100 if (!IIDecl) { 101 // None of the entities we found is a type, so there is no way 102 // to even assume that the result is a type. In this case, don't 103 // complain about the ambiguity. The parser will either try to 104 // perform this lookup again (e.g., as an object name), which 105 // will produce the ambiguity, or will complain that it expected 106 // a type name. 107 Result.Destroy(); 108 return 0; 109 } 110 111 // We found a type within the ambiguous lookup; diagnose the 112 // ambiguity and then return that type. This might be the right 113 // answer, or it might not be, but it suppresses any attempt to 114 // perform the name lookup again. 115 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 116 break; 117 } 118 119 case LookupResult::Found: 120 IIDecl = Result.getAsDecl(); 121 break; 122 } 123 124 if (IIDecl) { 125 QualType T; 126 127 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 128 // Check whether we can use this type 129 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 130 131 if (getLangOptions().CPlusPlus) { 132 // C++ [temp.local]p2: 133 // Within the scope of a class template specialization or 134 // partial specialization, when the injected-class-name is 135 // not followed by a <, it is equivalent to the 136 // injected-class-name followed by the template-argument s 137 // of the class template specialization or partial 138 // specialization enclosed in <>. 139 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 140 if (RD->isInjectedClassName()) 141 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 142 T = Template->getInjectedClassNameType(Context); 143 } 144 145 if (T.isNull()) 146 T = Context.getTypeDeclType(TD); 147 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 148 // Check whether we can use this interface. 149 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 150 151 T = Context.getObjCInterfaceType(IDecl); 152 } else 153 return 0; 154 155 if (SS) 156 T = getQualifiedNameType(*SS, T); 157 158 return T.getAsOpaquePtr(); 159 } 160 161 return 0; 162} 163 164/// isTagName() - This method is called *for error recovery purposes only* 165/// to determine if the specified name is a valid tag name ("struct foo"). If 166/// so, this returns the TST for the tag corresponding to it (TST_enum, 167/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 168/// where the user forgot to specify the tag. 169DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 170 // Do a tag name lookup in this scope. 171 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 172 if (R.getKind() == LookupResult::Found) 173 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 174 switch (TD->getTagKind()) { 175 case TagDecl::TK_struct: return DeclSpec::TST_struct; 176 case TagDecl::TK_union: return DeclSpec::TST_union; 177 case TagDecl::TK_class: return DeclSpec::TST_class; 178 case TagDecl::TK_enum: return DeclSpec::TST_enum; 179 } 180 } 181 182 return DeclSpec::TST_unspecified; 183} 184 185 186 187DeclContext *Sema::getContainingDC(DeclContext *DC) { 188 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 189 // A C++ out-of-line method will return to the file declaration context. 190 if (MD->isOutOfLine()) 191 return MD->getLexicalDeclContext(); 192 193 // A C++ inline method is parsed *after* the topmost class it was declared 194 // in is fully parsed (it's "complete"). 195 // The parsing of a C++ inline method happens at the declaration context of 196 // the topmost (non-nested) class it is lexically declared in. 197 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 198 DC = MD->getParent(); 199 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 200 DC = RD; 201 202 // Return the declaration context of the topmost class the inline method is 203 // declared in. 204 return DC; 205 } 206 207 if (isa<ObjCMethodDecl>(DC)) 208 return Context.getTranslationUnitDecl(); 209 210 return DC->getLexicalParent(); 211} 212 213void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 214 assert(getContainingDC(DC) == CurContext && 215 "The next DeclContext should be lexically contained in the current one."); 216 CurContext = DC; 217 S->setEntity(DC); 218} 219 220void Sema::PopDeclContext() { 221 assert(CurContext && "DeclContext imbalance!"); 222 223 CurContext = getContainingDC(CurContext); 224} 225 226/// EnterDeclaratorContext - Used when we must lookup names in the context 227/// of a declarator's nested name specifier. 228void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 229 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 230 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 231 CurContext = DC; 232 assert(CurContext && "No context?"); 233 S->setEntity(CurContext); 234} 235 236void Sema::ExitDeclaratorContext(Scope *S) { 237 S->setEntity(PreDeclaratorDC); 238 PreDeclaratorDC = 0; 239 240 // Reset CurContext to the nearest enclosing context. 241 while (!S->getEntity() && S->getParent()) 242 S = S->getParent(); 243 CurContext = static_cast<DeclContext*>(S->getEntity()); 244 assert(CurContext && "No context?"); 245} 246 247/// \brief Determine whether we allow overloading of the function 248/// PrevDecl with another declaration. 249/// 250/// This routine determines whether overloading is possible, not 251/// whether some new function is actually an overload. It will return 252/// true in C++ (where we can always provide overloads) or, as an 253/// extension, in C when the previous function is already an 254/// overloaded function declaration or has the "overloadable" 255/// attribute. 256static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 257 if (Context.getLangOptions().CPlusPlus) 258 return true; 259 260 if (isa<OverloadedFunctionDecl>(PrevDecl)) 261 return true; 262 263 return PrevDecl->getAttr<OverloadableAttr>() != 0; 264} 265 266/// Add this decl to the scope shadowed decl chains. 267void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 268 // Move up the scope chain until we find the nearest enclosing 269 // non-transparent context. The declaration will be introduced into this 270 // scope. 271 while (S->getEntity() && 272 ((DeclContext *)S->getEntity())->isTransparentContext()) 273 S = S->getParent(); 274 275 S->AddDecl(DeclPtrTy::make(D)); 276 277 // Add scoped declarations into their context, so that they can be 278 // found later. Declarations without a context won't be inserted 279 // into any context. 280 CurContext->addDecl(D); 281 282 // C++ [basic.scope]p4: 283 // -- exactly one declaration shall declare a class name or 284 // enumeration name that is not a typedef name and the other 285 // declarations shall all refer to the same object or 286 // enumerator, or all refer to functions and function templates; 287 // in this case the class name or enumeration name is hidden. 288 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 289 // We are pushing the name of a tag (enum or class). 290 if (CurContext->getLookupContext() 291 == TD->getDeclContext()->getLookupContext()) { 292 // We're pushing the tag into the current context, which might 293 // require some reshuffling in the identifier resolver. 294 IdentifierResolver::iterator 295 I = IdResolver.begin(TD->getDeclName()), 296 IEnd = IdResolver.end(); 297 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 298 NamedDecl *PrevDecl = *I; 299 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 300 PrevDecl = *I, ++I) { 301 if (TD->declarationReplaces(*I)) { 302 // This is a redeclaration. Remove it from the chain and 303 // break out, so that we'll add in the shadowed 304 // declaration. 305 S->RemoveDecl(DeclPtrTy::make(*I)); 306 if (PrevDecl == *I) { 307 IdResolver.RemoveDecl(*I); 308 IdResolver.AddDecl(TD); 309 return; 310 } else { 311 IdResolver.RemoveDecl(*I); 312 break; 313 } 314 } 315 } 316 317 // There is already a declaration with the same name in the same 318 // scope, which is not a tag declaration. It must be found 319 // before we find the new declaration, so insert the new 320 // declaration at the end of the chain. 321 IdResolver.AddShadowedDecl(TD, PrevDecl); 322 323 return; 324 } 325 } 326 } else if ((isa<FunctionDecl>(D) && 327 AllowOverloadingOfFunction(D, Context)) || 328 isa<FunctionTemplateDecl>(D)) { 329 // We are pushing the name of a function or function template, 330 // which might be an overloaded name. 331 IdentifierResolver::iterator Redecl 332 = std::find_if(IdResolver.begin(D->getDeclName()), 333 IdResolver.end(), 334 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 335 D)); 336 if (Redecl != IdResolver.end() && 337 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 338 // There is already a declaration of a function on our 339 // IdResolver chain. Replace it with this declaration. 340 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 341 IdResolver.RemoveDecl(*Redecl); 342 } 343 } else if (isa<ObjCInterfaceDecl>(D)) { 344 // We're pushing an Objective-C interface into the current 345 // context. If there is already an alias declaration, remove it first. 346 for (IdentifierResolver::iterator 347 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 348 I != IEnd; ++I) { 349 if (isa<ObjCCompatibleAliasDecl>(*I)) { 350 S->RemoveDecl(DeclPtrTy::make(*I)); 351 IdResolver.RemoveDecl(*I); 352 break; 353 } 354 } 355 } 356 357 IdResolver.AddDecl(D); 358} 359 360void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 361 if (S->decl_empty()) return; 362 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 363 "Scope shouldn't contain decls!"); 364 365 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 366 I != E; ++I) { 367 Decl *TmpD = (*I).getAs<Decl>(); 368 assert(TmpD && "This decl didn't get pushed??"); 369 370 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 371 NamedDecl *D = cast<NamedDecl>(TmpD); 372 373 if (!D->getDeclName()) continue; 374 375 // Remove this name from our lexical scope. 376 IdResolver.RemoveDecl(D); 377 } 378} 379 380/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 381/// return 0 if one not found. 382ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 383 // The third "scope" argument is 0 since we aren't enabling lazy built-in 384 // creation from this context. 385 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 386 387 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 388} 389 390/// getNonFieldDeclScope - Retrieves the innermost scope, starting 391/// from S, where a non-field would be declared. This routine copes 392/// with the difference between C and C++ scoping rules in structs and 393/// unions. For example, the following code is well-formed in C but 394/// ill-formed in C++: 395/// @code 396/// struct S6 { 397/// enum { BAR } e; 398/// }; 399/// 400/// void test_S6() { 401/// struct S6 a; 402/// a.e = BAR; 403/// } 404/// @endcode 405/// For the declaration of BAR, this routine will return a different 406/// scope. The scope S will be the scope of the unnamed enumeration 407/// within S6. In C++, this routine will return the scope associated 408/// with S6, because the enumeration's scope is a transparent 409/// context but structures can contain non-field names. In C, this 410/// routine will return the translation unit scope, since the 411/// enumeration's scope is a transparent context and structures cannot 412/// contain non-field names. 413Scope *Sema::getNonFieldDeclScope(Scope *S) { 414 while (((S->getFlags() & Scope::DeclScope) == 0) || 415 (S->getEntity() && 416 ((DeclContext *)S->getEntity())->isTransparentContext()) || 417 (S->isClassScope() && !getLangOptions().CPlusPlus)) 418 S = S->getParent(); 419 return S; 420} 421 422void Sema::InitBuiltinVaListType() { 423 if (!Context.getBuiltinVaListType().isNull()) 424 return; 425 426 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 427 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 428 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 429 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 430} 431 432/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 433/// file scope. lazily create a decl for it. ForRedeclaration is true 434/// if we're creating this built-in in anticipation of redeclaring the 435/// built-in. 436NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 437 Scope *S, bool ForRedeclaration, 438 SourceLocation Loc) { 439 Builtin::ID BID = (Builtin::ID)bid; 440 441 if (Context.BuiltinInfo.hasVAListUse(BID)) 442 InitBuiltinVaListType(); 443 444 ASTContext::GetBuiltinTypeError Error; 445 QualType R = Context.GetBuiltinType(BID, Error); 446 switch (Error) { 447 case ASTContext::GE_None: 448 // Okay 449 break; 450 451 case ASTContext::GE_Missing_FILE: 452 if (ForRedeclaration) 453 Diag(Loc, diag::err_implicit_decl_requires_stdio) 454 << Context.BuiltinInfo.GetName(BID); 455 return 0; 456 } 457 458 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 459 Diag(Loc, diag::ext_implicit_lib_function_decl) 460 << Context.BuiltinInfo.GetName(BID) 461 << R; 462 if (Context.BuiltinInfo.getHeaderName(BID) && 463 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 464 != Diagnostic::Ignored) 465 Diag(Loc, diag::note_please_include_header) 466 << Context.BuiltinInfo.getHeaderName(BID) 467 << Context.BuiltinInfo.GetName(BID); 468 } 469 470 FunctionDecl *New = FunctionDecl::Create(Context, 471 Context.getTranslationUnitDecl(), 472 Loc, II, R, 473 FunctionDecl::Extern, false, 474 /*hasPrototype=*/true); 475 New->setImplicit(); 476 477 // Create Decl objects for each parameter, adding them to the 478 // FunctionDecl. 479 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 480 llvm::SmallVector<ParmVarDecl*, 16> Params; 481 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 482 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 483 FT->getArgType(i), VarDecl::None, 0)); 484 New->setParams(Context, Params.data(), Params.size()); 485 } 486 487 AddKnownFunctionAttributes(New); 488 489 // TUScope is the translation-unit scope to insert this function into. 490 // FIXME: This is hideous. We need to teach PushOnScopeChains to 491 // relate Scopes to DeclContexts, and probably eliminate CurContext 492 // entirely, but we're not there yet. 493 DeclContext *SavedContext = CurContext; 494 CurContext = Context.getTranslationUnitDecl(); 495 PushOnScopeChains(New, TUScope); 496 CurContext = SavedContext; 497 return New; 498} 499 500/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 501/// everything from the standard library is defined. 502NamespaceDecl *Sema::GetStdNamespace() { 503 if (!StdNamespace) { 504 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 505 DeclContext *Global = Context.getTranslationUnitDecl(); 506 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 507 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 508 } 509 return StdNamespace; 510} 511 512/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 513/// same name and scope as a previous declaration 'Old'. Figure out 514/// how to resolve this situation, merging decls or emitting 515/// diagnostics as appropriate. If there was an error, set New to be invalid. 516/// 517void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 518 // If either decl is known invalid already, set the new one to be invalid and 519 // don't bother doing any merging checks. 520 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 521 return New->setInvalidDecl(); 522 523 // Allow multiple definitions for ObjC built-in typedefs. 524 // FIXME: Verify the underlying types are equivalent! 525 if (getLangOptions().ObjC1) { 526 const IdentifierInfo *TypeID = New->getIdentifier(); 527 switch (TypeID->getLength()) { 528 default: break; 529 case 2: 530 if (!TypeID->isStr("id")) 531 break; 532 // Install the built-in type for 'id', ignoring the current definition. 533 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 534 return; 535 case 5: 536 if (!TypeID->isStr("Class")) 537 break; 538 // Install the built-in type for 'Class', ignoring the current definition. 539 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 540 return; 541 case 3: 542 if (!TypeID->isStr("SEL")) 543 break; 544 Context.setObjCSelType(Context.getTypeDeclType(New)); 545 return; 546 case 8: 547 if (!TypeID->isStr("Protocol")) 548 break; 549 Context.setObjCProtoType(New->getUnderlyingType()); 550 return; 551 } 552 // Fall through - the typedef name was not a builtin type. 553 } 554 // Verify the old decl was also a type. 555 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 556 if (!Old) { 557 Diag(New->getLocation(), diag::err_redefinition_different_kind) 558 << New->getDeclName(); 559 if (OldD->getLocation().isValid()) 560 Diag(OldD->getLocation(), diag::note_previous_definition); 561 return New->setInvalidDecl(); 562 } 563 564 // Determine the "old" type we'll use for checking and diagnostics. 565 QualType OldType; 566 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 567 OldType = OldTypedef->getUnderlyingType(); 568 else 569 OldType = Context.getTypeDeclType(Old); 570 571 // If the typedef types are not identical, reject them in all languages and 572 // with any extensions enabled. 573 574 if (OldType != New->getUnderlyingType() && 575 Context.getCanonicalType(OldType) != 576 Context.getCanonicalType(New->getUnderlyingType())) { 577 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 578 << New->getUnderlyingType() << OldType; 579 if (Old->getLocation().isValid()) 580 Diag(Old->getLocation(), diag::note_previous_definition); 581 return New->setInvalidDecl(); 582 } 583 584 if (getLangOptions().Microsoft) 585 return; 586 587 // C++ [dcl.typedef]p2: 588 // In a given non-class scope, a typedef specifier can be used to 589 // redefine the name of any type declared in that scope to refer 590 // to the type to which it already refers. 591 if (getLangOptions().CPlusPlus) { 592 if (!isa<CXXRecordDecl>(CurContext)) 593 return; 594 Diag(New->getLocation(), diag::err_redefinition) 595 << New->getDeclName(); 596 Diag(Old->getLocation(), diag::note_previous_definition); 597 return New->setInvalidDecl(); 598 } 599 600 // If we have a redefinition of a typedef in C, emit a warning. This warning 601 // is normally mapped to an error, but can be controlled with 602 // -Wtypedef-redefinition. If either the original or the redefinition is 603 // in a system header, don't emit this for compatibility with GCC. 604 if (PP.getDiagnostics().getSuppressSystemWarnings() && 605 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 606 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 607 return; 608 609 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 610 << New->getDeclName(); 611 Diag(Old->getLocation(), diag::note_previous_definition); 612 return; 613} 614 615/// DeclhasAttr - returns true if decl Declaration already has the target 616/// attribute. 617static bool 618DeclHasAttr(const Decl *decl, const Attr *target) { 619 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 620 if (attr->getKind() == target->getKind()) 621 return true; 622 623 return false; 624} 625 626/// MergeAttributes - append attributes from the Old decl to the New one. 627static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 628 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 629 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 630 Attr *NewAttr = attr->clone(C); 631 NewAttr->setInherited(true); 632 New->addAttr(NewAttr); 633 } 634 } 635} 636 637/// Used in MergeFunctionDecl to keep track of function parameters in 638/// C. 639struct GNUCompatibleParamWarning { 640 ParmVarDecl *OldParm; 641 ParmVarDecl *NewParm; 642 QualType PromotedType; 643}; 644 645/// MergeFunctionDecl - We just parsed a function 'New' from 646/// declarator D which has the same name and scope as a previous 647/// declaration 'Old'. Figure out how to resolve this situation, 648/// merging decls or emitting diagnostics as appropriate. 649/// 650/// In C++, New and Old must be declarations that are not 651/// overloaded. Use IsOverload to determine whether New and Old are 652/// overloaded, and to select the Old declaration that New should be 653/// merged with. 654/// 655/// Returns true if there was an error, false otherwise. 656bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 657 assert(!isa<OverloadedFunctionDecl>(OldD) && 658 "Cannot merge with an overloaded function declaration"); 659 660 // Verify the old decl was also a function. 661 FunctionDecl *Old = 0; 662 if (FunctionTemplateDecl *OldFunctionTemplate 663 = dyn_cast<FunctionTemplateDecl>(OldD)) 664 Old = OldFunctionTemplate->getTemplatedDecl(); 665 else 666 Old = dyn_cast<FunctionDecl>(OldD); 667 if (!Old) { 668 Diag(New->getLocation(), diag::err_redefinition_different_kind) 669 << New->getDeclName(); 670 Diag(OldD->getLocation(), diag::note_previous_definition); 671 return true; 672 } 673 674 // Determine whether the previous declaration was a definition, 675 // implicit declaration, or a declaration. 676 diag::kind PrevDiag; 677 if (Old->isThisDeclarationADefinition()) 678 PrevDiag = diag::note_previous_definition; 679 else if (Old->isImplicit()) 680 PrevDiag = diag::note_previous_implicit_declaration; 681 else 682 PrevDiag = diag::note_previous_declaration; 683 684 QualType OldQType = Context.getCanonicalType(Old->getType()); 685 QualType NewQType = Context.getCanonicalType(New->getType()); 686 687 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 688 New->getStorageClass() == FunctionDecl::Static && 689 Old->getStorageClass() != FunctionDecl::Static) { 690 Diag(New->getLocation(), diag::err_static_non_static) 691 << New; 692 Diag(Old->getLocation(), PrevDiag); 693 return true; 694 } 695 696 if (getLangOptions().CPlusPlus) { 697 // (C++98 13.1p2): 698 // Certain function declarations cannot be overloaded: 699 // -- Function declarations that differ only in the return type 700 // cannot be overloaded. 701 QualType OldReturnType 702 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 703 QualType NewReturnType 704 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 705 if (OldReturnType != NewReturnType) { 706 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 707 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 708 return true; 709 } 710 711 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 712 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 713 if (OldMethod && NewMethod && 714 NewMethod->getLexicalDeclContext()->isRecord()) { 715 // -- Member function declarations with the same name and the 716 // same parameter types cannot be overloaded if any of them 717 // is a static member function declaration. 718 if (OldMethod->isStatic() || NewMethod->isStatic()) { 719 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 720 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 721 return true; 722 } 723 724 // C++ [class.mem]p1: 725 // [...] A member shall not be declared twice in the 726 // member-specification, except that a nested class or member 727 // class template can be declared and then later defined. 728 unsigned NewDiag; 729 if (isa<CXXConstructorDecl>(OldMethod)) 730 NewDiag = diag::err_constructor_redeclared; 731 else if (isa<CXXDestructorDecl>(NewMethod)) 732 NewDiag = diag::err_destructor_redeclared; 733 else if (isa<CXXConversionDecl>(NewMethod)) 734 NewDiag = diag::err_conv_function_redeclared; 735 else 736 NewDiag = diag::err_member_redeclared; 737 738 Diag(New->getLocation(), NewDiag); 739 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 740 } 741 742 // (C++98 8.3.5p3): 743 // All declarations for a function shall agree exactly in both the 744 // return type and the parameter-type-list. 745 if (OldQType == NewQType) 746 return MergeCompatibleFunctionDecls(New, Old); 747 748 // Fall through for conflicting redeclarations and redefinitions. 749 } 750 751 // C: Function types need to be compatible, not identical. This handles 752 // duplicate function decls like "void f(int); void f(enum X);" properly. 753 if (!getLangOptions().CPlusPlus && 754 Context.typesAreCompatible(OldQType, NewQType)) { 755 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 756 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 757 const FunctionProtoType *OldProto = 0; 758 if (isa<FunctionNoProtoType>(NewFuncType) && 759 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 760 // The old declaration provided a function prototype, but the 761 // new declaration does not. Merge in the prototype. 762 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 763 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 764 OldProto->arg_type_end()); 765 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 766 ParamTypes.data(), ParamTypes.size(), 767 OldProto->isVariadic(), 768 OldProto->getTypeQuals()); 769 New->setType(NewQType); 770 New->setHasInheritedPrototype(); 771 772 // Synthesize a parameter for each argument type. 773 llvm::SmallVector<ParmVarDecl*, 16> Params; 774 for (FunctionProtoType::arg_type_iterator 775 ParamType = OldProto->arg_type_begin(), 776 ParamEnd = OldProto->arg_type_end(); 777 ParamType != ParamEnd; ++ParamType) { 778 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 779 SourceLocation(), 0, 780 *ParamType, VarDecl::None, 781 0); 782 Param->setImplicit(); 783 Params.push_back(Param); 784 } 785 786 New->setParams(Context, Params.data(), Params.size()); 787 } 788 789 return MergeCompatibleFunctionDecls(New, Old); 790 } 791 792 // GNU C permits a K&R definition to follow a prototype declaration 793 // if the declared types of the parameters in the K&R definition 794 // match the types in the prototype declaration, even when the 795 // promoted types of the parameters from the K&R definition differ 796 // from the types in the prototype. GCC then keeps the types from 797 // the prototype. 798 // 799 // If a variadic prototype is followed by a non-variadic K&R definition, 800 // the K&R definition becomes variadic. This is sort of an edge case, but 801 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 802 // C99 6.9.1p8. 803 if (!getLangOptions().CPlusPlus && 804 Old->hasPrototype() && !New->hasPrototype() && 805 New->getType()->getAsFunctionProtoType() && 806 Old->getNumParams() == New->getNumParams()) { 807 llvm::SmallVector<QualType, 16> ArgTypes; 808 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 809 const FunctionProtoType *OldProto 810 = Old->getType()->getAsFunctionProtoType(); 811 const FunctionProtoType *NewProto 812 = New->getType()->getAsFunctionProtoType(); 813 814 // Determine whether this is the GNU C extension. 815 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 816 NewProto->getResultType()); 817 bool LooseCompatible = !MergedReturn.isNull(); 818 for (unsigned Idx = 0, End = Old->getNumParams(); 819 LooseCompatible && Idx != End; ++Idx) { 820 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 821 ParmVarDecl *NewParm = New->getParamDecl(Idx); 822 if (Context.typesAreCompatible(OldParm->getType(), 823 NewProto->getArgType(Idx))) { 824 ArgTypes.push_back(NewParm->getType()); 825 } else if (Context.typesAreCompatible(OldParm->getType(), 826 NewParm->getType())) { 827 GNUCompatibleParamWarning Warn 828 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 829 Warnings.push_back(Warn); 830 ArgTypes.push_back(NewParm->getType()); 831 } else 832 LooseCompatible = false; 833 } 834 835 if (LooseCompatible) { 836 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 837 Diag(Warnings[Warn].NewParm->getLocation(), 838 diag::ext_param_promoted_not_compatible_with_prototype) 839 << Warnings[Warn].PromotedType 840 << Warnings[Warn].OldParm->getType(); 841 Diag(Warnings[Warn].OldParm->getLocation(), 842 diag::note_previous_declaration); 843 } 844 845 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 846 ArgTypes.size(), 847 OldProto->isVariadic(), 0)); 848 return MergeCompatibleFunctionDecls(New, Old); 849 } 850 851 // Fall through to diagnose conflicting types. 852 } 853 854 // A function that has already been declared has been redeclared or defined 855 // with a different type- show appropriate diagnostic 856 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 857 // The user has declared a builtin function with an incompatible 858 // signature. 859 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 860 // The function the user is redeclaring is a library-defined 861 // function like 'malloc' or 'printf'. Warn about the 862 // redeclaration, then pretend that we don't know about this 863 // library built-in. 864 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 865 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 866 << Old << Old->getType(); 867 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 868 Old->setInvalidDecl(); 869 return false; 870 } 871 872 PrevDiag = diag::note_previous_builtin_declaration; 873 } 874 875 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 876 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 877 return true; 878} 879 880/// \brief Completes the merge of two function declarations that are 881/// known to be compatible. 882/// 883/// This routine handles the merging of attributes and other 884/// properties of function declarations form the old declaration to 885/// the new declaration, once we know that New is in fact a 886/// redeclaration of Old. 887/// 888/// \returns false 889bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 890 // Merge the attributes 891 MergeAttributes(New, Old, Context); 892 893 // Merge the storage class. 894 if (Old->getStorageClass() != FunctionDecl::Extern) 895 New->setStorageClass(Old->getStorageClass()); 896 897 // Merge "inline" 898 if (Old->isInline()) 899 New->setInline(true); 900 901 // If this function declaration by itself qualifies as a C99 inline 902 // definition (C99 6.7.4p6), but the previous definition did not, 903 // then the function is not a C99 inline definition. 904 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 905 New->setC99InlineDefinition(false); 906 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 907 // Mark all preceding definitions as not being C99 inline definitions. 908 for (const FunctionDecl *Prev = Old; Prev; 909 Prev = Prev->getPreviousDeclaration()) 910 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 911 } 912 913 // Merge "pure" flag. 914 if (Old->isPure()) 915 New->setPure(); 916 917 // Merge the "deleted" flag. 918 if (Old->isDeleted()) 919 New->setDeleted(); 920 921 if (getLangOptions().CPlusPlus) 922 return MergeCXXFunctionDecl(New, Old); 923 924 return false; 925} 926 927/// MergeVarDecl - We just parsed a variable 'New' which has the same name 928/// and scope as a previous declaration 'Old'. Figure out how to resolve this 929/// situation, merging decls or emitting diagnostics as appropriate. 930/// 931/// Tentative definition rules (C99 6.9.2p2) are checked by 932/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 933/// definitions here, since the initializer hasn't been attached. 934/// 935void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 936 // If either decl is invalid, make sure the new one is marked invalid and 937 // don't do any other checking. 938 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 939 return New->setInvalidDecl(); 940 941 // Verify the old decl was also a variable. 942 VarDecl *Old = dyn_cast<VarDecl>(OldD); 943 if (!Old) { 944 Diag(New->getLocation(), diag::err_redefinition_different_kind) 945 << New->getDeclName(); 946 Diag(OldD->getLocation(), diag::note_previous_definition); 947 return New->setInvalidDecl(); 948 } 949 950 MergeAttributes(New, Old, Context); 951 952 // Merge the types 953 QualType MergedT; 954 if (getLangOptions().CPlusPlus) { 955 if (Context.hasSameType(New->getType(), Old->getType())) 956 MergedT = New->getType(); 957 } else { 958 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 959 } 960 if (MergedT.isNull()) { 961 Diag(New->getLocation(), diag::err_redefinition_different_type) 962 << New->getDeclName(); 963 Diag(Old->getLocation(), diag::note_previous_definition); 964 return New->setInvalidDecl(); 965 } 966 New->setType(MergedT); 967 968 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 969 if (New->getStorageClass() == VarDecl::Static && 970 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 971 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 972 Diag(Old->getLocation(), diag::note_previous_definition); 973 return New->setInvalidDecl(); 974 } 975 // C99 6.2.2p4: 976 // For an identifier declared with the storage-class specifier 977 // extern in a scope in which a prior declaration of that 978 // identifier is visible,23) if the prior declaration specifies 979 // internal or external linkage, the linkage of the identifier at 980 // the later declaration is the same as the linkage specified at 981 // the prior declaration. If no prior declaration is visible, or 982 // if the prior declaration specifies no linkage, then the 983 // identifier has external linkage. 984 if (New->hasExternalStorage() && Old->hasLinkage()) 985 /* Okay */; 986 else if (New->getStorageClass() != VarDecl::Static && 987 Old->getStorageClass() == VarDecl::Static) { 988 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 989 Diag(Old->getLocation(), diag::note_previous_definition); 990 return New->setInvalidDecl(); 991 } 992 993 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 994 995 // FIXME: The test for external storage here seems wrong? We still 996 // need to check for mismatches. 997 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 998 // Don't complain about out-of-line definitions of static members. 999 !(Old->getLexicalDeclContext()->isRecord() && 1000 !New->getLexicalDeclContext()->isRecord())) { 1001 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1002 Diag(Old->getLocation(), diag::note_previous_definition); 1003 return New->setInvalidDecl(); 1004 } 1005 1006 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1007 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1008 Diag(Old->getLocation(), diag::note_previous_definition); 1009 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1010 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1011 Diag(Old->getLocation(), diag::note_previous_definition); 1012 } 1013 1014 // Keep a chain of previous declarations. 1015 New->setPreviousDeclaration(Old); 1016} 1017 1018/// CheckFallThrough - Check that we don't fall off the end of a 1019/// Statement that should return a value. 1020/// 1021/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1022/// MaybeFallThrough iff we might or might not fall off the end and 1023/// NeverFallThrough iff we never fall off the end of the statement. We assume 1024/// that functions not marked noreturn will return. 1025Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1026 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1027 1028 // FIXME: They should never return 0, fix that, delete this code. 1029 if (cfg == 0) 1030 return NeverFallThrough; 1031 // The CFG leaves in dead things, and we don't want to dead code paths to 1032 // confuse us, so we mark all live things first. 1033 std::queue<CFGBlock*> workq; 1034 llvm::BitVector live(cfg->getNumBlockIDs()); 1035 // Prep work queue 1036 workq.push(&cfg->getEntry()); 1037 // Solve 1038 while (!workq.empty()) { 1039 CFGBlock *item = workq.front(); 1040 workq.pop(); 1041 live.set(item->getBlockID()); 1042 for (CFGBlock::succ_iterator I=item->succ_begin(), 1043 E=item->succ_end(); 1044 I != E; 1045 ++I) { 1046 if ((*I) && !live[(*I)->getBlockID()]) { 1047 live.set((*I)->getBlockID()); 1048 workq.push(*I); 1049 } 1050 } 1051 } 1052 1053 // Now we know what is live, we check the live precessors of the exit block 1054 // and look for fall through paths, being careful to ignore normal returns, 1055 // and exceptional paths. 1056 bool HasLiveReturn = false; 1057 bool HasFakeEdge = false; 1058 bool HasPlainEdge = false; 1059 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1060 E = cfg->getExit().pred_end(); 1061 I != E; 1062 ++I) { 1063 CFGBlock& B = **I; 1064 if (!live[B.getBlockID()]) 1065 continue; 1066 if (B.size() == 0) { 1067 // A labeled empty statement, or the entry block... 1068 HasPlainEdge = true; 1069 continue; 1070 } 1071 Stmt *S = B[B.size()-1]; 1072 if (isa<ReturnStmt>(S)) { 1073 HasLiveReturn = true; 1074 continue; 1075 } 1076 if (isa<ObjCAtThrowStmt>(S)) { 1077 HasFakeEdge = true; 1078 continue; 1079 } 1080 if (isa<CXXThrowExpr>(S)) { 1081 HasFakeEdge = true; 1082 continue; 1083 } 1084 bool NoReturnEdge = false; 1085 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1086 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1087 if (CEE->getType().getNoReturnAttr()) { 1088 NoReturnEdge = true; 1089 HasFakeEdge = true; 1090 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1091 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1092 if (FD->hasAttr<NoReturnAttr>()) { 1093 NoReturnEdge = true; 1094 HasFakeEdge = true; 1095 } 1096 } 1097 } 1098 } 1099 // FIXME: Add noreturn message sends. 1100 if (NoReturnEdge == false) 1101 HasPlainEdge = true; 1102 } 1103 if (!HasPlainEdge) 1104 return NeverFallThrough; 1105 if (HasFakeEdge || HasLiveReturn) 1106 return MaybeFallThrough; 1107 // This says AlwaysFallThrough for calls to functions that are not marked 1108 // noreturn, that don't return. If people would like this warning to be more 1109 // accurate, such functions should be marked as noreturn. 1110 return AlwaysFallThrough; 1111} 1112 1113/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1114/// function that should return a value. Check that we don't fall off the end 1115/// of a noreturn function. We assume that functions not marked noreturn will 1116/// return. 1117void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1118 // FIXME: Would be nice if we had a better way to control cascading errors, 1119 // but for now, avoid them. The problem is that when Parse sees: 1120 // int foo() { return a; } 1121 // The return is eaten and the Sema code sees just: 1122 // int foo() { } 1123 // which this code would then warn about. 1124 if (getDiagnostics().hasErrorOccurred()) 1125 return; 1126 bool ReturnsVoid = false; 1127 bool HasNoReturn = false; 1128 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1129 if (FD->getResultType()->isVoidType()) 1130 ReturnsVoid = true; 1131 if (FD->hasAttr<NoReturnAttr>()) 1132 HasNoReturn = true; 1133 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1134 if (MD->getResultType()->isVoidType()) 1135 ReturnsVoid = true; 1136 if (MD->hasAttr<NoReturnAttr>()) 1137 HasNoReturn = true; 1138 } 1139 1140 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1141 == Diagnostic::Ignored || ReturnsVoid) 1142 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1143 == Diagnostic::Ignored || !HasNoReturn)) 1144 return; 1145 // FIXME: Funtion try block 1146 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1147 switch (CheckFallThrough(Body)) { 1148 case MaybeFallThrough: 1149 if (HasNoReturn) 1150 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1151 else if (!ReturnsVoid) 1152 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1153 break; 1154 case AlwaysFallThrough: 1155 if (HasNoReturn) 1156 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1157 else if (!ReturnsVoid) 1158 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1159 break; 1160 case NeverFallThrough: 1161 break; 1162 } 1163 } 1164} 1165 1166/// CheckParmsForFunctionDef - Check that the parameters of the given 1167/// function are appropriate for the definition of a function. This 1168/// takes care of any checks that cannot be performed on the 1169/// declaration itself, e.g., that the types of each of the function 1170/// parameters are complete. 1171bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1172 bool HasInvalidParm = false; 1173 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1174 ParmVarDecl *Param = FD->getParamDecl(p); 1175 1176 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1177 // function declarator that is part of a function definition of 1178 // that function shall not have incomplete type. 1179 // 1180 // This is also C++ [dcl.fct]p6. 1181 if (!Param->isInvalidDecl() && 1182 RequireCompleteType(Param->getLocation(), Param->getType(), 1183 diag::err_typecheck_decl_incomplete_type)) { 1184 Param->setInvalidDecl(); 1185 HasInvalidParm = true; 1186 } 1187 1188 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1189 // declaration of each parameter shall include an identifier. 1190 if (Param->getIdentifier() == 0 && 1191 !Param->isImplicit() && 1192 !getLangOptions().CPlusPlus) 1193 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1194 } 1195 1196 return HasInvalidParm; 1197} 1198 1199/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1200/// no declarator (e.g. "struct foo;") is parsed. 1201Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1202 // FIXME: Error on auto/register at file scope 1203 // FIXME: Error on inline/virtual/explicit 1204 // FIXME: Error on invalid restrict 1205 // FIXME: Warn on useless __thread 1206 // FIXME: Warn on useless const/volatile 1207 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1208 // FIXME: Warn on useless attributes 1209 TagDecl *Tag = 0; 1210 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1211 DS.getTypeSpecType() == DeclSpec::TST_struct || 1212 DS.getTypeSpecType() == DeclSpec::TST_union || 1213 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1214 if (!DS.getTypeRep()) // We probably had an error 1215 return DeclPtrTy(); 1216 1217 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1218 } 1219 1220 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1221 if (!Record->getDeclName() && Record->isDefinition() && 1222 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1223 if (getLangOptions().CPlusPlus || 1224 Record->getDeclContext()->isRecord()) 1225 return BuildAnonymousStructOrUnion(S, DS, Record); 1226 1227 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1228 << DS.getSourceRange(); 1229 } 1230 1231 // Microsoft allows unnamed struct/union fields. Don't complain 1232 // about them. 1233 // FIXME: Should we support Microsoft's extensions in this area? 1234 if (Record->getDeclName() && getLangOptions().Microsoft) 1235 return DeclPtrTy::make(Tag); 1236 } 1237 1238 if (!DS.isMissingDeclaratorOk() && 1239 DS.getTypeSpecType() != DeclSpec::TST_error) { 1240 // Warn about typedefs of enums without names, since this is an 1241 // extension in both Microsoft an GNU. 1242 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1243 Tag && isa<EnumDecl>(Tag)) { 1244 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1245 << DS.getSourceRange(); 1246 return DeclPtrTy::make(Tag); 1247 } 1248 1249 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1250 << DS.getSourceRange(); 1251 return DeclPtrTy(); 1252 } 1253 1254 return DeclPtrTy::make(Tag); 1255} 1256 1257/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1258/// anonymous struct or union AnonRecord into the owning context Owner 1259/// and scope S. This routine will be invoked just after we realize 1260/// that an unnamed union or struct is actually an anonymous union or 1261/// struct, e.g., 1262/// 1263/// @code 1264/// union { 1265/// int i; 1266/// float f; 1267/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1268/// // f into the surrounding scope.x 1269/// @endcode 1270/// 1271/// This routine is recursive, injecting the names of nested anonymous 1272/// structs/unions into the owning context and scope as well. 1273bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1274 RecordDecl *AnonRecord) { 1275 bool Invalid = false; 1276 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1277 FEnd = AnonRecord->field_end(); 1278 F != FEnd; ++F) { 1279 if ((*F)->getDeclName()) { 1280 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1281 LookupOrdinaryName, true); 1282 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1283 // C++ [class.union]p2: 1284 // The names of the members of an anonymous union shall be 1285 // distinct from the names of any other entity in the 1286 // scope in which the anonymous union is declared. 1287 unsigned diagKind 1288 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1289 : diag::err_anonymous_struct_member_redecl; 1290 Diag((*F)->getLocation(), diagKind) 1291 << (*F)->getDeclName(); 1292 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1293 Invalid = true; 1294 } else { 1295 // C++ [class.union]p2: 1296 // For the purpose of name lookup, after the anonymous union 1297 // definition, the members of the anonymous union are 1298 // considered to have been defined in the scope in which the 1299 // anonymous union is declared. 1300 Owner->makeDeclVisibleInContext(*F); 1301 S->AddDecl(DeclPtrTy::make(*F)); 1302 IdResolver.AddDecl(*F); 1303 } 1304 } else if (const RecordType *InnerRecordType 1305 = (*F)->getType()->getAsRecordType()) { 1306 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1307 if (InnerRecord->isAnonymousStructOrUnion()) 1308 Invalid = Invalid || 1309 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1310 } 1311 } 1312 1313 return Invalid; 1314} 1315 1316/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1317/// anonymous structure or union. Anonymous unions are a C++ feature 1318/// (C++ [class.union]) and a GNU C extension; anonymous structures 1319/// are a GNU C and GNU C++ extension. 1320Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1321 RecordDecl *Record) { 1322 DeclContext *Owner = Record->getDeclContext(); 1323 1324 // Diagnose whether this anonymous struct/union is an extension. 1325 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1326 Diag(Record->getLocation(), diag::ext_anonymous_union); 1327 else if (!Record->isUnion()) 1328 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1329 1330 // C and C++ require different kinds of checks for anonymous 1331 // structs/unions. 1332 bool Invalid = false; 1333 if (getLangOptions().CPlusPlus) { 1334 const char* PrevSpec = 0; 1335 // C++ [class.union]p3: 1336 // Anonymous unions declared in a named namespace or in the 1337 // global namespace shall be declared static. 1338 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1339 (isa<TranslationUnitDecl>(Owner) || 1340 (isa<NamespaceDecl>(Owner) && 1341 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1342 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1343 Invalid = true; 1344 1345 // Recover by adding 'static'. 1346 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1347 } 1348 // C++ [class.union]p3: 1349 // A storage class is not allowed in a declaration of an 1350 // anonymous union in a class scope. 1351 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1352 isa<RecordDecl>(Owner)) { 1353 Diag(DS.getStorageClassSpecLoc(), 1354 diag::err_anonymous_union_with_storage_spec); 1355 Invalid = true; 1356 1357 // Recover by removing the storage specifier. 1358 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1359 PrevSpec); 1360 } 1361 1362 // C++ [class.union]p2: 1363 // The member-specification of an anonymous union shall only 1364 // define non-static data members. [Note: nested types and 1365 // functions cannot be declared within an anonymous union. ] 1366 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1367 MemEnd = Record->decls_end(); 1368 Mem != MemEnd; ++Mem) { 1369 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1370 // C++ [class.union]p3: 1371 // An anonymous union shall not have private or protected 1372 // members (clause 11). 1373 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1374 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1375 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1376 Invalid = true; 1377 } 1378 } else if ((*Mem)->isImplicit()) { 1379 // Any implicit members are fine. 1380 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1381 // This is a type that showed up in an 1382 // elaborated-type-specifier inside the anonymous struct or 1383 // union, but which actually declares a type outside of the 1384 // anonymous struct or union. It's okay. 1385 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1386 if (!MemRecord->isAnonymousStructOrUnion() && 1387 MemRecord->getDeclName()) { 1388 // This is a nested type declaration. 1389 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1390 << (int)Record->isUnion(); 1391 Invalid = true; 1392 } 1393 } else { 1394 // We have something that isn't a non-static data 1395 // member. Complain about it. 1396 unsigned DK = diag::err_anonymous_record_bad_member; 1397 if (isa<TypeDecl>(*Mem)) 1398 DK = diag::err_anonymous_record_with_type; 1399 else if (isa<FunctionDecl>(*Mem)) 1400 DK = diag::err_anonymous_record_with_function; 1401 else if (isa<VarDecl>(*Mem)) 1402 DK = diag::err_anonymous_record_with_static; 1403 Diag((*Mem)->getLocation(), DK) 1404 << (int)Record->isUnion(); 1405 Invalid = true; 1406 } 1407 } 1408 } 1409 1410 if (!Record->isUnion() && !Owner->isRecord()) { 1411 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1412 << (int)getLangOptions().CPlusPlus; 1413 Invalid = true; 1414 } 1415 1416 // Create a declaration for this anonymous struct/union. 1417 NamedDecl *Anon = 0; 1418 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1419 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1420 /*IdentifierInfo=*/0, 1421 Context.getTypeDeclType(Record), 1422 /*BitWidth=*/0, /*Mutable=*/false, 1423 DS.getSourceRange().getBegin()); 1424 Anon->setAccess(AS_public); 1425 if (getLangOptions().CPlusPlus) 1426 FieldCollector->Add(cast<FieldDecl>(Anon)); 1427 } else { 1428 VarDecl::StorageClass SC; 1429 switch (DS.getStorageClassSpec()) { 1430 default: assert(0 && "Unknown storage class!"); 1431 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1432 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1433 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1434 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1435 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1436 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1437 case DeclSpec::SCS_mutable: 1438 // mutable can only appear on non-static class members, so it's always 1439 // an error here 1440 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1441 Invalid = true; 1442 SC = VarDecl::None; 1443 break; 1444 } 1445 1446 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1447 /*IdentifierInfo=*/0, 1448 Context.getTypeDeclType(Record), 1449 SC, DS.getSourceRange().getBegin()); 1450 } 1451 Anon->setImplicit(); 1452 1453 // Add the anonymous struct/union object to the current 1454 // context. We'll be referencing this object when we refer to one of 1455 // its members. 1456 Owner->addDecl(Anon); 1457 1458 // Inject the members of the anonymous struct/union into the owning 1459 // context and into the identifier resolver chain for name lookup 1460 // purposes. 1461 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1462 Invalid = true; 1463 1464 // Mark this as an anonymous struct/union type. Note that we do not 1465 // do this until after we have already checked and injected the 1466 // members of this anonymous struct/union type, because otherwise 1467 // the members could be injected twice: once by DeclContext when it 1468 // builds its lookup table, and once by 1469 // InjectAnonymousStructOrUnionMembers. 1470 Record->setAnonymousStructOrUnion(true); 1471 1472 if (Invalid) 1473 Anon->setInvalidDecl(); 1474 1475 return DeclPtrTy::make(Anon); 1476} 1477 1478 1479/// GetNameForDeclarator - Determine the full declaration name for the 1480/// given Declarator. 1481DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1482 switch (D.getKind()) { 1483 case Declarator::DK_Abstract: 1484 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1485 return DeclarationName(); 1486 1487 case Declarator::DK_Normal: 1488 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1489 return DeclarationName(D.getIdentifier()); 1490 1491 case Declarator::DK_Constructor: { 1492 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1493 Ty = Context.getCanonicalType(Ty); 1494 return Context.DeclarationNames.getCXXConstructorName(Ty); 1495 } 1496 1497 case Declarator::DK_Destructor: { 1498 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1499 Ty = Context.getCanonicalType(Ty); 1500 return Context.DeclarationNames.getCXXDestructorName(Ty); 1501 } 1502 1503 case Declarator::DK_Conversion: { 1504 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1505 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1506 Ty = Context.getCanonicalType(Ty); 1507 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1508 } 1509 1510 case Declarator::DK_Operator: 1511 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1512 return Context.DeclarationNames.getCXXOperatorName( 1513 D.getOverloadedOperator()); 1514 } 1515 1516 assert(false && "Unknown name kind"); 1517 return DeclarationName(); 1518} 1519 1520/// isNearlyMatchingFunction - Determine whether the C++ functions 1521/// Declaration and Definition are "nearly" matching. This heuristic 1522/// is used to improve diagnostics in the case where an out-of-line 1523/// function definition doesn't match any declaration within 1524/// the class or namespace. 1525static bool isNearlyMatchingFunction(ASTContext &Context, 1526 FunctionDecl *Declaration, 1527 FunctionDecl *Definition) { 1528 if (Declaration->param_size() != Definition->param_size()) 1529 return false; 1530 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1531 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1532 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1533 1534 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1535 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1536 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1537 return false; 1538 } 1539 1540 return true; 1541} 1542 1543Sema::DeclPtrTy 1544Sema::HandleDeclarator(Scope *S, Declarator &D, 1545 MultiTemplateParamsArg TemplateParamLists, 1546 bool IsFunctionDefinition) { 1547 DeclarationName Name = GetNameForDeclarator(D); 1548 1549 // All of these full declarators require an identifier. If it doesn't have 1550 // one, the ParsedFreeStandingDeclSpec action should be used. 1551 if (!Name) { 1552 if (!D.isInvalidType()) // Reject this if we think it is valid. 1553 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1554 diag::err_declarator_need_ident) 1555 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1556 return DeclPtrTy(); 1557 } 1558 1559 // The scope passed in may not be a decl scope. Zip up the scope tree until 1560 // we find one that is. 1561 while ((S->getFlags() & Scope::DeclScope) == 0 || 1562 (S->getFlags() & Scope::TemplateParamScope) != 0) 1563 S = S->getParent(); 1564 1565 DeclContext *DC; 1566 NamedDecl *PrevDecl; 1567 NamedDecl *New; 1568 1569 QualType R = GetTypeForDeclarator(D, S); 1570 1571 // See if this is a redefinition of a variable in the same scope. 1572 if (D.getCXXScopeSpec().isInvalid()) { 1573 DC = CurContext; 1574 PrevDecl = 0; 1575 D.setInvalidType(); 1576 } else if (!D.getCXXScopeSpec().isSet()) { 1577 LookupNameKind NameKind = LookupOrdinaryName; 1578 1579 // If the declaration we're planning to build will be a function 1580 // or object with linkage, then look for another declaration with 1581 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1582 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1583 /* Do nothing*/; 1584 else if (R->isFunctionType()) { 1585 if (CurContext->isFunctionOrMethod() || 1586 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1587 NameKind = LookupRedeclarationWithLinkage; 1588 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1589 NameKind = LookupRedeclarationWithLinkage; 1590 else if (CurContext->getLookupContext()->isTranslationUnit() && 1591 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1592 NameKind = LookupRedeclarationWithLinkage; 1593 1594 DC = CurContext; 1595 PrevDecl = LookupName(S, Name, NameKind, true, 1596 NameKind == LookupRedeclarationWithLinkage, 1597 D.getIdentifierLoc()); 1598 } else { // Something like "int foo::x;" 1599 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1600 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1601 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1602 1603 // C++ 7.3.1.2p2: 1604 // Members (including explicit specializations of templates) of a named 1605 // namespace can also be defined outside that namespace by explicit 1606 // qualification of the name being defined, provided that the entity being 1607 // defined was already declared in the namespace and the definition appears 1608 // after the point of declaration in a namespace that encloses the 1609 // declarations namespace. 1610 // 1611 // Note that we only check the context at this point. We don't yet 1612 // have enough information to make sure that PrevDecl is actually 1613 // the declaration we want to match. For example, given: 1614 // 1615 // class X { 1616 // void f(); 1617 // void f(float); 1618 // }; 1619 // 1620 // void X::f(int) { } // ill-formed 1621 // 1622 // In this case, PrevDecl will point to the overload set 1623 // containing the two f's declared in X, but neither of them 1624 // matches. 1625 1626 // First check whether we named the global scope. 1627 if (isa<TranslationUnitDecl>(DC)) { 1628 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1629 << Name << D.getCXXScopeSpec().getRange(); 1630 } else if (!CurContext->Encloses(DC)) { 1631 // The qualifying scope doesn't enclose the original declaration. 1632 // Emit diagnostic based on current scope. 1633 SourceLocation L = D.getIdentifierLoc(); 1634 SourceRange R = D.getCXXScopeSpec().getRange(); 1635 if (isa<FunctionDecl>(CurContext)) 1636 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1637 else 1638 Diag(L, diag::err_invalid_declarator_scope) 1639 << Name << cast<NamedDecl>(DC) << R; 1640 D.setInvalidType(); 1641 } 1642 } 1643 1644 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1645 // Maybe we will complain about the shadowed template parameter. 1646 if (!D.isInvalidType()) 1647 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1648 D.setInvalidType(); 1649 1650 // Just pretend that we didn't see the previous declaration. 1651 PrevDecl = 0; 1652 } 1653 1654 // In C++, the previous declaration we find might be a tag type 1655 // (class or enum). In this case, the new declaration will hide the 1656 // tag type. Note that this does does not apply if we're declaring a 1657 // typedef (C++ [dcl.typedef]p4). 1658 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1659 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1660 PrevDecl = 0; 1661 1662 bool Redeclaration = false; 1663 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1664 if (TemplateParamLists.size()) { 1665 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1666 return DeclPtrTy(); 1667 } 1668 1669 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1670 } else if (R->isFunctionType()) { 1671 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1672 move(TemplateParamLists), 1673 IsFunctionDefinition, Redeclaration); 1674 } else { 1675 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1676 move(TemplateParamLists), 1677 Redeclaration); 1678 } 1679 1680 if (New == 0) 1681 return DeclPtrTy(); 1682 1683 // If this has an identifier and is not an invalid redeclaration, 1684 // add it to the scope stack. 1685 if (Name && !(Redeclaration && New->isInvalidDecl())) 1686 PushOnScopeChains(New, S); 1687 1688 return DeclPtrTy::make(New); 1689} 1690 1691/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1692/// types into constant array types in certain situations which would otherwise 1693/// be errors (for GCC compatibility). 1694static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1695 ASTContext &Context, 1696 bool &SizeIsNegative) { 1697 // This method tries to turn a variable array into a constant 1698 // array even when the size isn't an ICE. This is necessary 1699 // for compatibility with code that depends on gcc's buggy 1700 // constant expression folding, like struct {char x[(int)(char*)2];} 1701 SizeIsNegative = false; 1702 1703 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1704 QualType Pointee = PTy->getPointeeType(); 1705 QualType FixedType = 1706 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1707 if (FixedType.isNull()) return FixedType; 1708 FixedType = Context.getPointerType(FixedType); 1709 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1710 return FixedType; 1711 } 1712 1713 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1714 if (!VLATy) 1715 return QualType(); 1716 // FIXME: We should probably handle this case 1717 if (VLATy->getElementType()->isVariablyModifiedType()) 1718 return QualType(); 1719 1720 Expr::EvalResult EvalResult; 1721 if (!VLATy->getSizeExpr() || 1722 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1723 !EvalResult.Val.isInt()) 1724 return QualType(); 1725 1726 llvm::APSInt &Res = EvalResult.Val.getInt(); 1727 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1728 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1729 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1730 // so as to transfer ownership to the ConstantArrayWithExpr. 1731 // Alternatively, we could "clone" it (how?). 1732 // Since we don't know how to do things above, we just use the 1733 // very same Expr*. 1734 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1735 Res, ArySizeExpr, 1736 ArrayType::Normal, 0, 1737 VLATy->getBracketsRange()); 1738 } 1739 1740 SizeIsNegative = true; 1741 return QualType(); 1742} 1743 1744/// \brief Register the given locally-scoped external C declaration so 1745/// that it can be found later for redeclarations 1746void 1747Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1748 Scope *S) { 1749 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1750 "Decl is not a locally-scoped decl!"); 1751 // Note that we have a locally-scoped external with this name. 1752 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1753 1754 if (!PrevDecl) 1755 return; 1756 1757 // If there was a previous declaration of this variable, it may be 1758 // in our identifier chain. Update the identifier chain with the new 1759 // declaration. 1760 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1761 // The previous declaration was found on the identifer resolver 1762 // chain, so remove it from its scope. 1763 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1764 S = S->getParent(); 1765 1766 if (S) 1767 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1768 } 1769} 1770 1771/// \brief Diagnose function specifiers on a declaration of an identifier that 1772/// does not identify a function. 1773void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1774 // FIXME: We should probably indicate the identifier in question to avoid 1775 // confusion for constructs like "inline int a(), b;" 1776 if (D.getDeclSpec().isInlineSpecified()) 1777 Diag(D.getDeclSpec().getInlineSpecLoc(), 1778 diag::err_inline_non_function); 1779 1780 if (D.getDeclSpec().isVirtualSpecified()) 1781 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1782 diag::err_virtual_non_function); 1783 1784 if (D.getDeclSpec().isExplicitSpecified()) 1785 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1786 diag::err_explicit_non_function); 1787} 1788 1789NamedDecl* 1790Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1791 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1792 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1793 if (D.getCXXScopeSpec().isSet()) { 1794 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1795 << D.getCXXScopeSpec().getRange(); 1796 D.setInvalidType(); 1797 // Pretend we didn't see the scope specifier. 1798 DC = 0; 1799 } 1800 1801 if (getLangOptions().CPlusPlus) { 1802 // Check that there are no default arguments (C++ only). 1803 CheckExtraCXXDefaultArguments(D); 1804 } 1805 1806 DiagnoseFunctionSpecifiers(D); 1807 1808 if (D.getDeclSpec().isThreadSpecified()) 1809 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1810 1811 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1812 if (!NewTD) return 0; 1813 1814 if (D.isInvalidType()) 1815 NewTD->setInvalidDecl(); 1816 1817 // Handle attributes prior to checking for duplicates in MergeVarDecl 1818 ProcessDeclAttributes(S, NewTD, D); 1819 // Merge the decl with the existing one if appropriate. If the decl is 1820 // in an outer scope, it isn't the same thing. 1821 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1822 Redeclaration = true; 1823 MergeTypeDefDecl(NewTD, PrevDecl); 1824 } 1825 1826 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1827 // then it shall have block scope. 1828 QualType T = NewTD->getUnderlyingType(); 1829 if (T->isVariablyModifiedType()) { 1830 CurFunctionNeedsScopeChecking = true; 1831 1832 if (S->getFnParent() == 0) { 1833 bool SizeIsNegative; 1834 QualType FixedTy = 1835 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1836 if (!FixedTy.isNull()) { 1837 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1838 NewTD->setUnderlyingType(FixedTy); 1839 } else { 1840 if (SizeIsNegative) 1841 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1842 else if (T->isVariableArrayType()) 1843 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1844 else 1845 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1846 NewTD->setInvalidDecl(); 1847 } 1848 } 1849 } 1850 1851 // If this is the C FILE type, notify the AST context. 1852 if (IdentifierInfo *II = NewTD->getIdentifier()) 1853 if (!NewTD->isInvalidDecl() && 1854 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit() && 1855 II->isStr("FILE")) 1856 Context.setFILEDecl(NewTD); 1857 1858 return NewTD; 1859} 1860 1861/// \brief Determines whether the given declaration is an out-of-scope 1862/// previous declaration. 1863/// 1864/// This routine should be invoked when name lookup has found a 1865/// previous declaration (PrevDecl) that is not in the scope where a 1866/// new declaration by the same name is being introduced. If the new 1867/// declaration occurs in a local scope, previous declarations with 1868/// linkage may still be considered previous declarations (C99 1869/// 6.2.2p4-5, C++ [basic.link]p6). 1870/// 1871/// \param PrevDecl the previous declaration found by name 1872/// lookup 1873/// 1874/// \param DC the context in which the new declaration is being 1875/// declared. 1876/// 1877/// \returns true if PrevDecl is an out-of-scope previous declaration 1878/// for a new delcaration with the same name. 1879static bool 1880isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1881 ASTContext &Context) { 1882 if (!PrevDecl) 1883 return 0; 1884 1885 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1886 // case we need to check each of the overloaded functions. 1887 if (!PrevDecl->hasLinkage()) 1888 return false; 1889 1890 if (Context.getLangOptions().CPlusPlus) { 1891 // C++ [basic.link]p6: 1892 // If there is a visible declaration of an entity with linkage 1893 // having the same name and type, ignoring entities declared 1894 // outside the innermost enclosing namespace scope, the block 1895 // scope declaration declares that same entity and receives the 1896 // linkage of the previous declaration. 1897 DeclContext *OuterContext = DC->getLookupContext(); 1898 if (!OuterContext->isFunctionOrMethod()) 1899 // This rule only applies to block-scope declarations. 1900 return false; 1901 else { 1902 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1903 if (PrevOuterContext->isRecord()) 1904 // We found a member function: ignore it. 1905 return false; 1906 else { 1907 // Find the innermost enclosing namespace for the new and 1908 // previous declarations. 1909 while (!OuterContext->isFileContext()) 1910 OuterContext = OuterContext->getParent(); 1911 while (!PrevOuterContext->isFileContext()) 1912 PrevOuterContext = PrevOuterContext->getParent(); 1913 1914 // The previous declaration is in a different namespace, so it 1915 // isn't the same function. 1916 if (OuterContext->getPrimaryContext() != 1917 PrevOuterContext->getPrimaryContext()) 1918 return false; 1919 } 1920 } 1921 } 1922 1923 return true; 1924} 1925 1926NamedDecl* 1927Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1928 QualType R,NamedDecl* PrevDecl, 1929 MultiTemplateParamsArg TemplateParamLists, 1930 bool &Redeclaration) { 1931 DeclarationName Name = GetNameForDeclarator(D); 1932 1933 // Check that there are no default arguments (C++ only). 1934 if (getLangOptions().CPlusPlus) 1935 CheckExtraCXXDefaultArguments(D); 1936 1937 VarDecl *NewVD; 1938 VarDecl::StorageClass SC; 1939 switch (D.getDeclSpec().getStorageClassSpec()) { 1940 default: assert(0 && "Unknown storage class!"); 1941 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1942 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1943 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1944 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1945 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1946 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1947 case DeclSpec::SCS_mutable: 1948 // mutable can only appear on non-static class members, so it's always 1949 // an error here 1950 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1951 D.setInvalidType(); 1952 SC = VarDecl::None; 1953 break; 1954 } 1955 1956 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1957 if (!II) { 1958 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1959 << Name.getAsString(); 1960 return 0; 1961 } 1962 1963 DiagnoseFunctionSpecifiers(D); 1964 1965 if (!DC->isRecord() && S->getFnParent() == 0) { 1966 // C99 6.9p2: The storage-class specifiers auto and register shall not 1967 // appear in the declaration specifiers in an external declaration. 1968 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1969 1970 // If this is a register variable with an asm label specified, then this 1971 // is a GNU extension. 1972 if (SC == VarDecl::Register && D.getAsmLabel()) 1973 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1974 else 1975 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1976 D.setInvalidType(); 1977 } 1978 } 1979 if (DC->isRecord() && !CurContext->isRecord()) { 1980 // This is an out-of-line definition of a static data member. 1981 if (SC == VarDecl::Static) { 1982 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1983 diag::err_static_out_of_line) 1984 << CodeModificationHint::CreateRemoval( 1985 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1986 } else if (SC == VarDecl::None) 1987 SC = VarDecl::Static; 1988 } 1989 if (SC == VarDecl::Static) { 1990 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 1991 if (RD->isLocalClass()) 1992 Diag(D.getIdentifierLoc(), 1993 diag::err_static_data_member_not_allowed_in_local_class) 1994 << Name << RD->getDeclName(); 1995 } 1996 } 1997 1998 // Check that we can declare a template here. 1999 if (TemplateParamLists.size() && 2000 CheckTemplateDeclScope(S, TemplateParamLists)) 2001 return 0; 2002 2003 // Match up the template parameter lists with the scope specifier, then 2004 // determine whether we have a template or a template specialization. 2005 if (TemplateParameterList *TemplateParams 2006 = MatchTemplateParametersToScopeSpecifier( 2007 D.getDeclSpec().getSourceRange().getBegin(), 2008 D.getCXXScopeSpec(), 2009 (TemplateParameterList**)TemplateParamLists.get(), 2010 TemplateParamLists.size())) { 2011 if (TemplateParams->size() > 0) { 2012 // There is no such thing as a variable template. 2013 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2014 << II 2015 << SourceRange(TemplateParams->getTemplateLoc(), 2016 TemplateParams->getRAngleLoc()); 2017 return 0; 2018 } else { 2019 // There is an extraneous 'template<>' for this variable. Complain 2020 // about it, but allow the declaration of the variable. 2021 Diag(TemplateParams->getTemplateLoc(), 2022 diag::err_template_variable_noparams) 2023 << II 2024 << SourceRange(TemplateParams->getTemplateLoc(), 2025 TemplateParams->getRAngleLoc()); 2026 } 2027 } 2028 2029 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2030 II, R, SC, 2031 // FIXME: Move to DeclGroup... 2032 D.getDeclSpec().getSourceRange().getBegin()); 2033 2034 if (D.isInvalidType()) 2035 NewVD->setInvalidDecl(); 2036 2037 if (D.getDeclSpec().isThreadSpecified()) { 2038 if (NewVD->hasLocalStorage()) 2039 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2040 else if (!Context.Target.isTLSSupported()) 2041 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2042 else 2043 NewVD->setThreadSpecified(true); 2044 } 2045 2046 // Set the lexical context. If the declarator has a C++ scope specifier, the 2047 // lexical context will be different from the semantic context. 2048 NewVD->setLexicalDeclContext(CurContext); 2049 2050 // Handle attributes prior to checking for duplicates in MergeVarDecl 2051 ProcessDeclAttributes(S, NewVD, D); 2052 2053 // Handle GNU asm-label extension (encoded as an attribute). 2054 if (Expr *E = (Expr*) D.getAsmLabel()) { 2055 // The parser guarantees this is a string. 2056 StringLiteral *SE = cast<StringLiteral>(E); 2057 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2058 SE->getByteLength()))); 2059 } 2060 2061 // If name lookup finds a previous declaration that is not in the 2062 // same scope as the new declaration, this may still be an 2063 // acceptable redeclaration. 2064 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2065 !(NewVD->hasLinkage() && 2066 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2067 PrevDecl = 0; 2068 2069 // Merge the decl with the existing one if appropriate. 2070 if (PrevDecl) { 2071 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2072 // The user tried to define a non-static data member 2073 // out-of-line (C++ [dcl.meaning]p1). 2074 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2075 << D.getCXXScopeSpec().getRange(); 2076 PrevDecl = 0; 2077 NewVD->setInvalidDecl(); 2078 } 2079 } else if (D.getCXXScopeSpec().isSet()) { 2080 // No previous declaration in the qualifying scope. 2081 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 2082 << Name << D.getCXXScopeSpec().getRange(); 2083 NewVD->setInvalidDecl(); 2084 } 2085 2086 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2087 2088 // attributes declared post-definition are currently ignored 2089 if (PrevDecl) { 2090 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2091 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2092 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2093 Diag(Def->getLocation(), diag::note_previous_definition); 2094 } 2095 } 2096 2097 // If this is a locally-scoped extern C variable, update the map of 2098 // such variables. 2099 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2100 !NewVD->isInvalidDecl()) 2101 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2102 2103 return NewVD; 2104} 2105 2106/// \brief Perform semantic checking on a newly-created variable 2107/// declaration. 2108/// 2109/// This routine performs all of the type-checking required for a 2110/// variable declaration once it has been built. It is used both to 2111/// check variables after they have been parsed and their declarators 2112/// have been translated into a declaration, and to check variables 2113/// that have been instantiated from a template. 2114/// 2115/// Sets NewVD->isInvalidDecl() if an error was encountered. 2116void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2117 bool &Redeclaration) { 2118 // If the decl is already known invalid, don't check it. 2119 if (NewVD->isInvalidDecl()) 2120 return; 2121 2122 QualType T = NewVD->getType(); 2123 2124 if (T->isObjCInterfaceType()) { 2125 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2126 return NewVD->setInvalidDecl(); 2127 } 2128 2129 // The variable can not have an abstract class type. 2130 if (RequireNonAbstractType(NewVD->getLocation(), T, 2131 diag::err_abstract_type_in_decl, 2132 AbstractVariableType)) 2133 return NewVD->setInvalidDecl(); 2134 2135 // Emit an error if an address space was applied to decl with local storage. 2136 // This includes arrays of objects with address space qualifiers, but not 2137 // automatic variables that point to other address spaces. 2138 // ISO/IEC TR 18037 S5.1.2 2139 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2140 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2141 return NewVD->setInvalidDecl(); 2142 } 2143 2144 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2145 && !NewVD->hasAttr<BlocksAttr>()) 2146 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2147 2148 bool isVM = T->isVariablyModifiedType(); 2149 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2150 NewVD->hasAttr<BlocksAttr>()) 2151 CurFunctionNeedsScopeChecking = true; 2152 2153 if ((isVM && NewVD->hasLinkage()) || 2154 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2155 bool SizeIsNegative; 2156 QualType FixedTy = 2157 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2158 2159 if (FixedTy.isNull() && T->isVariableArrayType()) { 2160 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2161 // FIXME: This won't give the correct result for 2162 // int a[10][n]; 2163 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2164 2165 if (NewVD->isFileVarDecl()) 2166 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2167 << SizeRange; 2168 else if (NewVD->getStorageClass() == VarDecl::Static) 2169 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2170 << SizeRange; 2171 else 2172 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2173 << SizeRange; 2174 return NewVD->setInvalidDecl(); 2175 } 2176 2177 if (FixedTy.isNull()) { 2178 if (NewVD->isFileVarDecl()) 2179 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2180 else 2181 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2182 return NewVD->setInvalidDecl(); 2183 } 2184 2185 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2186 NewVD->setType(FixedTy); 2187 } 2188 2189 if (!PrevDecl && NewVD->isExternC(Context)) { 2190 // Since we did not find anything by this name and we're declaring 2191 // an extern "C" variable, look for a non-visible extern "C" 2192 // declaration with the same name. 2193 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2194 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2195 if (Pos != LocallyScopedExternalDecls.end()) 2196 PrevDecl = Pos->second; 2197 } 2198 2199 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2200 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2201 << T; 2202 return NewVD->setInvalidDecl(); 2203 } 2204 2205 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2206 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2207 return NewVD->setInvalidDecl(); 2208 } 2209 2210 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2211 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2212 return NewVD->setInvalidDecl(); 2213 } 2214 2215 if (PrevDecl) { 2216 Redeclaration = true; 2217 MergeVarDecl(NewVD, PrevDecl); 2218 } 2219} 2220 2221NamedDecl* 2222Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2223 QualType R, NamedDecl* PrevDecl, 2224 MultiTemplateParamsArg TemplateParamLists, 2225 bool IsFunctionDefinition, bool &Redeclaration) { 2226 assert(R.getTypePtr()->isFunctionType()); 2227 2228 DeclarationName Name = GetNameForDeclarator(D); 2229 FunctionDecl::StorageClass SC = FunctionDecl::None; 2230 switch (D.getDeclSpec().getStorageClassSpec()) { 2231 default: assert(0 && "Unknown storage class!"); 2232 case DeclSpec::SCS_auto: 2233 case DeclSpec::SCS_register: 2234 case DeclSpec::SCS_mutable: 2235 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2236 diag::err_typecheck_sclass_func); 2237 D.setInvalidType(); 2238 break; 2239 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2240 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2241 case DeclSpec::SCS_static: { 2242 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2243 // C99 6.7.1p5: 2244 // The declaration of an identifier for a function that has 2245 // block scope shall have no explicit storage-class specifier 2246 // other than extern 2247 // See also (C++ [dcl.stc]p4). 2248 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2249 diag::err_static_block_func); 2250 SC = FunctionDecl::None; 2251 } else 2252 SC = FunctionDecl::Static; 2253 break; 2254 } 2255 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2256 } 2257 2258 if (D.getDeclSpec().isThreadSpecified()) 2259 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2260 2261 bool isInline = D.getDeclSpec().isInlineSpecified(); 2262 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2263 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2264 2265 // Check that the return type is not an abstract class type. 2266 // For record types, this is done by the AbstractClassUsageDiagnoser once 2267 // the class has been completely parsed. 2268 if (!DC->isRecord() && 2269 RequireNonAbstractType(D.getIdentifierLoc(), 2270 R->getAsFunctionType()->getResultType(), 2271 diag::err_abstract_type_in_decl, 2272 AbstractReturnType)) 2273 D.setInvalidType(); 2274 2275 // Do not allow returning a objc interface by-value. 2276 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2277 Diag(D.getIdentifierLoc(), 2278 diag::err_object_cannot_be_passed_returned_by_value) << 0 2279 << R->getAsFunctionType()->getResultType(); 2280 D.setInvalidType(); 2281 } 2282 2283 // Check that we can declare a template here. 2284 if (TemplateParamLists.size() && 2285 CheckTemplateDeclScope(S, TemplateParamLists)) 2286 return 0; 2287 2288 bool isVirtualOkay = false; 2289 FunctionDecl *NewFD; 2290 if (D.getKind() == Declarator::DK_Constructor) { 2291 // This is a C++ constructor declaration. 2292 assert(DC->isRecord() && 2293 "Constructors can only be declared in a member context"); 2294 2295 R = CheckConstructorDeclarator(D, R, SC); 2296 2297 // Create the new declaration 2298 NewFD = CXXConstructorDecl::Create(Context, 2299 cast<CXXRecordDecl>(DC), 2300 D.getIdentifierLoc(), Name, R, 2301 isExplicit, isInline, 2302 /*isImplicitlyDeclared=*/false); 2303 } else if (D.getKind() == Declarator::DK_Destructor) { 2304 // This is a C++ destructor declaration. 2305 if (DC->isRecord()) { 2306 R = CheckDestructorDeclarator(D, SC); 2307 2308 NewFD = CXXDestructorDecl::Create(Context, 2309 cast<CXXRecordDecl>(DC), 2310 D.getIdentifierLoc(), Name, R, 2311 isInline, 2312 /*isImplicitlyDeclared=*/false); 2313 2314 isVirtualOkay = true; 2315 } else { 2316 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2317 2318 // Create a FunctionDecl to satisfy the function definition parsing 2319 // code path. 2320 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2321 Name, R, SC, isInline, 2322 /*hasPrototype=*/true, 2323 // FIXME: Move to DeclGroup... 2324 D.getDeclSpec().getSourceRange().getBegin()); 2325 D.setInvalidType(); 2326 } 2327 } else if (D.getKind() == Declarator::DK_Conversion) { 2328 if (!DC->isRecord()) { 2329 Diag(D.getIdentifierLoc(), 2330 diag::err_conv_function_not_member); 2331 return 0; 2332 } 2333 2334 CheckConversionDeclarator(D, R, SC); 2335 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2336 D.getIdentifierLoc(), Name, R, 2337 isInline, isExplicit); 2338 2339 isVirtualOkay = true; 2340 } else if (DC->isRecord()) { 2341 // If the of the function is the same as the name of the record, then this 2342 // must be an invalid constructor that has a return type. 2343 // (The parser checks for a return type and makes the declarator a 2344 // constructor if it has no return type). 2345 // must have an invalid constructor that has a return type 2346 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2347 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2348 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2349 << SourceRange(D.getIdentifierLoc()); 2350 return 0; 2351 } 2352 2353 // This is a C++ method declaration. 2354 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2355 D.getIdentifierLoc(), Name, R, 2356 (SC == FunctionDecl::Static), isInline); 2357 2358 isVirtualOkay = (SC != FunctionDecl::Static); 2359 } else { 2360 // Determine whether the function was written with a 2361 // prototype. This true when: 2362 // - we're in C++ (where every function has a prototype), 2363 // - there is a prototype in the declarator, or 2364 // - the type R of the function is some kind of typedef or other reference 2365 // to a type name (which eventually refers to a function type). 2366 bool HasPrototype = 2367 getLangOptions().CPlusPlus || 2368 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2369 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2370 2371 NewFD = FunctionDecl::Create(Context, DC, 2372 D.getIdentifierLoc(), 2373 Name, R, SC, isInline, HasPrototype, 2374 // FIXME: Move to DeclGroup... 2375 D.getDeclSpec().getSourceRange().getBegin()); 2376 } 2377 2378 if (D.isInvalidType()) 2379 NewFD->setInvalidDecl(); 2380 2381 // Set the lexical context. If the declarator has a C++ 2382 // scope specifier, the lexical context will be different 2383 // from the semantic context. 2384 NewFD->setLexicalDeclContext(CurContext); 2385 2386 // Match up the template parameter lists with the scope specifier, then 2387 // determine whether we have a template or a template specialization. 2388 FunctionTemplateDecl *FunctionTemplate = 0; 2389 if (TemplateParameterList *TemplateParams 2390 = MatchTemplateParametersToScopeSpecifier( 2391 D.getDeclSpec().getSourceRange().getBegin(), 2392 D.getCXXScopeSpec(), 2393 (TemplateParameterList**)TemplateParamLists.get(), 2394 TemplateParamLists.size())) { 2395 if (TemplateParams->size() > 0) { 2396 // This is a function template 2397 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2398 NewFD->getLocation(), 2399 Name, TemplateParams, 2400 NewFD); 2401 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2402 } else { 2403 // FIXME: Handle function template specializations 2404 } 2405 2406 // FIXME: Free this memory properly. 2407 TemplateParamLists.release(); 2408 } 2409 2410 // C++ [dcl.fct.spec]p5: 2411 // The virtual specifier shall only be used in declarations of 2412 // nonstatic class member functions that appear within a 2413 // member-specification of a class declaration; see 10.3. 2414 // 2415 if (isVirtual && !NewFD->isInvalidDecl()) { 2416 if (!isVirtualOkay) { 2417 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2418 diag::err_virtual_non_function); 2419 } else if (!CurContext->isRecord()) { 2420 // 'virtual' was specified outside of the class. 2421 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2422 << CodeModificationHint::CreateRemoval( 2423 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2424 } else { 2425 // Okay: Add virtual to the method. 2426 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2427 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2428 CurClass->setAggregate(false); 2429 CurClass->setPOD(false); 2430 CurClass->setPolymorphic(true); 2431 CurClass->setHasTrivialConstructor(false); 2432 CurClass->setHasTrivialCopyConstructor(false); 2433 CurClass->setHasTrivialCopyAssignment(false); 2434 } 2435 } 2436 2437 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2438 // Look for virtual methods in base classes that this method might override. 2439 2440 BasePaths Paths; 2441 if (LookupInBases(cast<CXXRecordDecl>(DC), 2442 MemberLookupCriteria(NewMD), Paths)) { 2443 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2444 E = Paths.found_decls_end(); I != E; ++I) { 2445 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2446 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2447 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2448 NewMD->addOverriddenMethod(OldMD); 2449 } 2450 } 2451 } 2452 } 2453 2454 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2455 !CurContext->isRecord()) { 2456 // C++ [class.static]p1: 2457 // A data or function member of a class may be declared static 2458 // in a class definition, in which case it is a static member of 2459 // the class. 2460 2461 // Complain about the 'static' specifier if it's on an out-of-line 2462 // member function definition. 2463 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2464 diag::err_static_out_of_line) 2465 << CodeModificationHint::CreateRemoval( 2466 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2467 } 2468 2469 // Handle GNU asm-label extension (encoded as an attribute). 2470 if (Expr *E = (Expr*) D.getAsmLabel()) { 2471 // The parser guarantees this is a string. 2472 StringLiteral *SE = cast<StringLiteral>(E); 2473 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2474 SE->getByteLength()))); 2475 } 2476 2477 // Copy the parameter declarations from the declarator D to the function 2478 // declaration NewFD, if they are available. First scavenge them into Params. 2479 llvm::SmallVector<ParmVarDecl*, 16> Params; 2480 if (D.getNumTypeObjects() > 0) { 2481 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2482 2483 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2484 // function that takes no arguments, not a function that takes a 2485 // single void argument. 2486 // We let through "const void" here because Sema::GetTypeForDeclarator 2487 // already checks for that case. 2488 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2489 FTI.ArgInfo[0].Param && 2490 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2491 // Empty arg list, don't push any params. 2492 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2493 2494 // In C++, the empty parameter-type-list must be spelled "void"; a 2495 // typedef of void is not permitted. 2496 if (getLangOptions().CPlusPlus && 2497 Param->getType().getUnqualifiedType() != Context.VoidTy) 2498 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2499 // FIXME: Leaks decl? 2500 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2501 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2502 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2503 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2504 Param->setDeclContext(NewFD); 2505 Params.push_back(Param); 2506 } 2507 } 2508 2509 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2510 // When we're declaring a function with a typedef, typeof, etc as in the 2511 // following example, we'll need to synthesize (unnamed) 2512 // parameters for use in the declaration. 2513 // 2514 // @code 2515 // typedef void fn(int); 2516 // fn f; 2517 // @endcode 2518 2519 // Synthesize a parameter for each argument type. 2520 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2521 AE = FT->arg_type_end(); AI != AE; ++AI) { 2522 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2523 SourceLocation(), 0, 2524 *AI, VarDecl::None, 0); 2525 Param->setImplicit(); 2526 Params.push_back(Param); 2527 } 2528 } else { 2529 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2530 "Should not need args for typedef of non-prototype fn"); 2531 } 2532 // Finally, we know we have the right number of parameters, install them. 2533 NewFD->setParams(Context, Params.data(), Params.size()); 2534 2535 // If name lookup finds a previous declaration that is not in the 2536 // same scope as the new declaration, this may still be an 2537 // acceptable redeclaration. 2538 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2539 !(NewFD->hasLinkage() && 2540 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2541 PrevDecl = 0; 2542 2543 // Perform semantic checking on the function declaration. 2544 bool OverloadableAttrRequired = false; // FIXME: HACK! 2545 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2546 /*FIXME:*/OverloadableAttrRequired); 2547 2548 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2549 // An out-of-line member function declaration must also be a 2550 // definition (C++ [dcl.meaning]p1). 2551 if (!IsFunctionDefinition) { 2552 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2553 << D.getCXXScopeSpec().getRange(); 2554 NewFD->setInvalidDecl(); 2555 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2556 // The user tried to provide an out-of-line definition for a 2557 // function that is a member of a class or namespace, but there 2558 // was no such member function declared (C++ [class.mfct]p2, 2559 // C++ [namespace.memdef]p2). For example: 2560 // 2561 // class X { 2562 // void f() const; 2563 // }; 2564 // 2565 // void X::f() { } // ill-formed 2566 // 2567 // Complain about this problem, and attempt to suggest close 2568 // matches (e.g., those that differ only in cv-qualifiers and 2569 // whether the parameter types are references). 2570 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2571 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2572 NewFD->setInvalidDecl(); 2573 2574 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2575 true); 2576 assert(!Prev.isAmbiguous() && 2577 "Cannot have an ambiguity in previous-declaration lookup"); 2578 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2579 Func != FuncEnd; ++Func) { 2580 if (isa<FunctionDecl>(*Func) && 2581 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2582 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2583 } 2584 2585 PrevDecl = 0; 2586 } 2587 } 2588 2589 // Handle attributes. We need to have merged decls when handling attributes 2590 // (for example to check for conflicts, etc). 2591 // FIXME: This needs to happen before we merge declarations. Then, 2592 // let attribute merging cope with attribute conflicts. 2593 ProcessDeclAttributes(S, NewFD, D); 2594 2595 // attributes declared post-definition are currently ignored 2596 if (PrevDecl) { 2597 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2598 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2599 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2600 Diag(Def->getLocation(), diag::note_previous_definition); 2601 } 2602 } 2603 2604 AddKnownFunctionAttributes(NewFD); 2605 2606 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2607 // If a function name is overloadable in C, then every function 2608 // with that name must be marked "overloadable". 2609 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2610 << Redeclaration << NewFD; 2611 if (PrevDecl) 2612 Diag(PrevDecl->getLocation(), 2613 diag::note_attribute_overloadable_prev_overload); 2614 NewFD->addAttr(::new (Context) OverloadableAttr()); 2615 } 2616 2617 // If this is a locally-scoped extern C function, update the 2618 // map of such names. 2619 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2620 && !NewFD->isInvalidDecl()) 2621 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2622 2623 // Set this FunctionDecl's range up to the right paren. 2624 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2625 2626 if (FunctionTemplate && NewFD->isInvalidDecl()) 2627 FunctionTemplate->setInvalidDecl(); 2628 2629 if (FunctionTemplate) 2630 return FunctionTemplate; 2631 2632 return NewFD; 2633} 2634 2635/// \brief Perform semantic checking of a new function declaration. 2636/// 2637/// Performs semantic analysis of the new function declaration 2638/// NewFD. This routine performs all semantic checking that does not 2639/// require the actual declarator involved in the declaration, and is 2640/// used both for the declaration of functions as they are parsed 2641/// (called via ActOnDeclarator) and for the declaration of functions 2642/// that have been instantiated via C++ template instantiation (called 2643/// via InstantiateDecl). 2644/// 2645/// This sets NewFD->isInvalidDecl() to true if there was an error. 2646void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2647 bool &Redeclaration, 2648 bool &OverloadableAttrRequired) { 2649 // If NewFD is already known erroneous, don't do any of this checking. 2650 if (NewFD->isInvalidDecl()) 2651 return; 2652 2653 if (NewFD->getResultType()->isVariablyModifiedType()) { 2654 // Functions returning a variably modified type violate C99 6.7.5.2p2 2655 // because all functions have linkage. 2656 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2657 return NewFD->setInvalidDecl(); 2658 } 2659 2660 if (NewFD->isMain()) CheckMain(NewFD); 2661 2662 // Semantic checking for this function declaration (in isolation). 2663 if (getLangOptions().CPlusPlus) { 2664 // C++-specific checks. 2665 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2666 CheckConstructor(Constructor); 2667 } else if (isa<CXXDestructorDecl>(NewFD)) { 2668 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2669 QualType ClassType = Context.getTypeDeclType(Record); 2670 if (!ClassType->isDependentType()) { 2671 ClassType = Context.getCanonicalType(ClassType); 2672 DeclarationName Name 2673 = Context.DeclarationNames.getCXXDestructorName(ClassType); 2674 if (NewFD->getDeclName() != Name) { 2675 Diag(NewFD->getLocation(), diag::err_destructor_name); 2676 return NewFD->setInvalidDecl(); 2677 } 2678 } 2679 Record->setUserDeclaredDestructor(true); 2680 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2681 // user-defined destructor. 2682 Record->setPOD(false); 2683 2684 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2685 // declared destructor. 2686 // FIXME: C++0x: don't do this for "= default" destructors 2687 Record->setHasTrivialDestructor(false); 2688 } else if (CXXConversionDecl *Conversion 2689 = dyn_cast<CXXConversionDecl>(NewFD)) 2690 ActOnConversionDeclarator(Conversion); 2691 2692 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2693 if (NewFD->isOverloadedOperator() && 2694 CheckOverloadedOperatorDeclaration(NewFD)) 2695 return NewFD->setInvalidDecl(); 2696 } 2697 2698 // C99 6.7.4p6: 2699 // [... ] For a function with external linkage, the following 2700 // restrictions apply: [...] If all of the file scope declarations 2701 // for a function in a translation unit include the inline 2702 // function specifier without extern, then the definition in that 2703 // translation unit is an inline definition. An inline definition 2704 // does not provide an external definition for the function, and 2705 // does not forbid an external definition in another translation 2706 // unit. 2707 // 2708 // Here we determine whether this function, in isolation, would be a 2709 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2710 // previous declarations. 2711 if (NewFD->isInline() && getLangOptions().C99 && 2712 NewFD->getStorageClass() == FunctionDecl::None && 2713 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2714 NewFD->setC99InlineDefinition(true); 2715 2716 // Check for a previous declaration of this name. 2717 if (!PrevDecl && NewFD->isExternC(Context)) { 2718 // Since we did not find anything by this name and we're declaring 2719 // an extern "C" function, look for a non-visible extern "C" 2720 // declaration with the same name. 2721 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2722 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2723 if (Pos != LocallyScopedExternalDecls.end()) 2724 PrevDecl = Pos->second; 2725 } 2726 2727 // Merge or overload the declaration with an existing declaration of 2728 // the same name, if appropriate. 2729 if (PrevDecl) { 2730 // Determine whether NewFD is an overload of PrevDecl or 2731 // a declaration that requires merging. If it's an overload, 2732 // there's no more work to do here; we'll just add the new 2733 // function to the scope. 2734 OverloadedFunctionDecl::function_iterator MatchedDecl; 2735 2736 if (!getLangOptions().CPlusPlus && 2737 AllowOverloadingOfFunction(PrevDecl, Context)) { 2738 OverloadableAttrRequired = true; 2739 2740 // Functions marked "overloadable" must have a prototype (that 2741 // we can't get through declaration merging). 2742 if (!NewFD->getType()->getAsFunctionProtoType()) { 2743 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2744 << NewFD; 2745 Redeclaration = true; 2746 2747 // Turn this into a variadic function with no parameters. 2748 QualType R = Context.getFunctionType( 2749 NewFD->getType()->getAsFunctionType()->getResultType(), 2750 0, 0, true, 0); 2751 NewFD->setType(R); 2752 return NewFD->setInvalidDecl(); 2753 } 2754 } 2755 2756 if (PrevDecl && 2757 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2758 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2759 !isa<UsingDecl>(PrevDecl)) { 2760 Redeclaration = true; 2761 Decl *OldDecl = PrevDecl; 2762 2763 // If PrevDecl was an overloaded function, extract the 2764 // FunctionDecl that matched. 2765 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2766 OldDecl = *MatchedDecl; 2767 2768 // NewFD and OldDecl represent declarations that need to be 2769 // merged. 2770 if (MergeFunctionDecl(NewFD, OldDecl)) 2771 return NewFD->setInvalidDecl(); 2772 2773 if (FunctionTemplateDecl *OldTemplateDecl 2774 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2775 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2776 else { 2777 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2778 NewFD->setAccess(OldDecl->getAccess()); 2779 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2780 } 2781 } 2782 } 2783 2784 // In C++, check default arguments now that we have merged decls. Unless 2785 // the lexical context is the class, because in this case this is done 2786 // during delayed parsing anyway. 2787 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2788 CheckCXXDefaultArguments(NewFD); 2789} 2790 2791void Sema::CheckMain(FunctionDecl* FD) { 2792 // C++ [basic.start.main]p3: A program that declares main to be inline 2793 // or static is ill-formed. 2794 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2795 // shall not appear in a declaration of main. 2796 // static main is not an error under C99, but we should warn about it. 2797 bool isInline = FD->isInline(); 2798 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2799 if (isInline || isStatic) { 2800 unsigned diagID = diag::warn_unusual_main_decl; 2801 if (isInline || getLangOptions().CPlusPlus) 2802 diagID = diag::err_unusual_main_decl; 2803 2804 int which = isStatic + (isInline << 1) - 1; 2805 Diag(FD->getLocation(), diagID) << which; 2806 } 2807 2808 QualType T = FD->getType(); 2809 assert(T->isFunctionType() && "function decl is not of function type"); 2810 const FunctionType* FT = T->getAsFunctionType(); 2811 2812 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2813 // TODO: add a replacement fixit to turn the return type into 'int'. 2814 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2815 FD->setInvalidDecl(true); 2816 } 2817 2818 // Treat protoless main() as nullary. 2819 if (isa<FunctionNoProtoType>(FT)) return; 2820 2821 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2822 unsigned nparams = FTP->getNumArgs(); 2823 assert(FD->getNumParams() == nparams); 2824 2825 if (nparams > 3) { 2826 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2827 FD->setInvalidDecl(true); 2828 nparams = 3; 2829 } 2830 2831 // FIXME: a lot of the following diagnostics would be improved 2832 // if we had some location information about types. 2833 2834 QualType CharPP = 2835 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2836 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2837 2838 for (unsigned i = 0; i < nparams; ++i) { 2839 QualType AT = FTP->getArgType(i); 2840 2841 bool mismatch = true; 2842 2843 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2844 mismatch = false; 2845 else if (Expected[i] == CharPP) { 2846 // As an extension, the following forms are okay: 2847 // char const ** 2848 // char const * const * 2849 // char * const * 2850 2851 QualifierSet qs; 2852 const PointerType* PT; 2853 if ((PT = qs.strip(AT)->getAsPointerType()) && 2854 (PT = qs.strip(PT->getPointeeType())->getAsPointerType()) && 2855 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2856 qs.removeConst(); 2857 mismatch = !qs.empty(); 2858 } 2859 } 2860 2861 if (mismatch) { 2862 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 2863 // TODO: suggest replacing given type with expected type 2864 FD->setInvalidDecl(true); 2865 } 2866 } 2867 2868 if (nparams == 1 && !FD->isInvalidDecl()) { 2869 Diag(FD->getLocation(), diag::warn_main_one_arg); 2870 } 2871} 2872 2873bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2874 // FIXME: Need strict checking. In C89, we need to check for 2875 // any assignment, increment, decrement, function-calls, or 2876 // commas outside of a sizeof. In C99, it's the same list, 2877 // except that the aforementioned are allowed in unevaluated 2878 // expressions. Everything else falls under the 2879 // "may accept other forms of constant expressions" exception. 2880 // (We never end up here for C++, so the constant expression 2881 // rules there don't matter.) 2882 if (Init->isConstantInitializer(Context)) 2883 return false; 2884 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2885 << Init->getSourceRange(); 2886 return true; 2887} 2888 2889void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2890 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2891} 2892 2893/// AddInitializerToDecl - Adds the initializer Init to the 2894/// declaration dcl. If DirectInit is true, this is C++ direct 2895/// initialization rather than copy initialization. 2896void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2897 Decl *RealDecl = dcl.getAs<Decl>(); 2898 // If there is no declaration, there was an error parsing it. Just ignore 2899 // the initializer. 2900 if (RealDecl == 0) 2901 return; 2902 2903 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2904 // With declarators parsed the way they are, the parser cannot 2905 // distinguish between a normal initializer and a pure-specifier. 2906 // Thus this grotesque test. 2907 IntegerLiteral *IL; 2908 Expr *Init = static_cast<Expr *>(init.get()); 2909 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2910 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2911 if (Method->isVirtualAsWritten()) { 2912 Method->setPure(); 2913 2914 // A class is abstract if at least one function is pure virtual. 2915 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2916 } else if (!Method->isInvalidDecl()) { 2917 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2918 << Method->getDeclName() << Init->getSourceRange(); 2919 Method->setInvalidDecl(); 2920 } 2921 } else { 2922 Diag(Method->getLocation(), diag::err_member_function_initialization) 2923 << Method->getDeclName() << Init->getSourceRange(); 2924 Method->setInvalidDecl(); 2925 } 2926 return; 2927 } 2928 2929 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2930 if (!VDecl) { 2931 if (getLangOptions().CPlusPlus && 2932 RealDecl->getLexicalDeclContext()->isRecord() && 2933 isa<NamedDecl>(RealDecl)) 2934 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2935 << cast<NamedDecl>(RealDecl)->getDeclName(); 2936 else 2937 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2938 RealDecl->setInvalidDecl(); 2939 return; 2940 } 2941 2942 if (!VDecl->getType()->isArrayType() && 2943 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2944 diag::err_typecheck_decl_incomplete_type)) { 2945 RealDecl->setInvalidDecl(); 2946 return; 2947 } 2948 2949 const VarDecl *Def = 0; 2950 if (VDecl->getDefinition(Def)) { 2951 Diag(VDecl->getLocation(), diag::err_redefinition) 2952 << VDecl->getDeclName(); 2953 Diag(Def->getLocation(), diag::note_previous_definition); 2954 VDecl->setInvalidDecl(); 2955 return; 2956 } 2957 2958 // Take ownership of the expression, now that we're sure we have somewhere 2959 // to put it. 2960 Expr *Init = init.takeAs<Expr>(); 2961 assert(Init && "missing initializer"); 2962 2963 // Get the decls type and save a reference for later, since 2964 // CheckInitializerTypes may change it. 2965 QualType DclT = VDecl->getType(), SavT = DclT; 2966 if (VDecl->isBlockVarDecl()) { 2967 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2968 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2969 VDecl->setInvalidDecl(); 2970 } else if (!VDecl->isInvalidDecl()) { 2971 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2972 VDecl->getDeclName(), DirectInit)) 2973 VDecl->setInvalidDecl(); 2974 2975 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2976 // Don't check invalid declarations to avoid emitting useless diagnostics. 2977 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2978 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2979 CheckForConstantInitializer(Init, DclT); 2980 } 2981 } 2982 } else if (VDecl->isStaticDataMember() && 2983 VDecl->getLexicalDeclContext()->isRecord()) { 2984 // This is an in-class initialization for a static data member, e.g., 2985 // 2986 // struct S { 2987 // static const int value = 17; 2988 // }; 2989 2990 // Attach the initializer 2991 VDecl->setInit(Context, Init); 2992 2993 // C++ [class.mem]p4: 2994 // A member-declarator can contain a constant-initializer only 2995 // if it declares a static member (9.4) of const integral or 2996 // const enumeration type, see 9.4.2. 2997 QualType T = VDecl->getType(); 2998 if (!T->isDependentType() && 2999 (!Context.getCanonicalType(T).isConstQualified() || 3000 !T->isIntegralType())) { 3001 Diag(VDecl->getLocation(), diag::err_member_initialization) 3002 << VDecl->getDeclName() << Init->getSourceRange(); 3003 VDecl->setInvalidDecl(); 3004 } else { 3005 // C++ [class.static.data]p4: 3006 // If a static data member is of const integral or const 3007 // enumeration type, its declaration in the class definition 3008 // can specify a constant-initializer which shall be an 3009 // integral constant expression (5.19). 3010 if (!Init->isTypeDependent() && 3011 !Init->getType()->isIntegralType()) { 3012 // We have a non-dependent, non-integral or enumeration type. 3013 Diag(Init->getSourceRange().getBegin(), 3014 diag::err_in_class_initializer_non_integral_type) 3015 << Init->getType() << Init->getSourceRange(); 3016 VDecl->setInvalidDecl(); 3017 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3018 // Check whether the expression is a constant expression. 3019 llvm::APSInt Value; 3020 SourceLocation Loc; 3021 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3022 Diag(Loc, diag::err_in_class_initializer_non_constant) 3023 << Init->getSourceRange(); 3024 VDecl->setInvalidDecl(); 3025 } else if (!VDecl->getType()->isDependentType()) 3026 ImpCastExprToType(Init, VDecl->getType()); 3027 } 3028 } 3029 } else if (VDecl->isFileVarDecl()) { 3030 if (VDecl->getStorageClass() == VarDecl::Extern) 3031 Diag(VDecl->getLocation(), diag::warn_extern_init); 3032 if (!VDecl->isInvalidDecl()) 3033 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3034 VDecl->getDeclName(), DirectInit)) 3035 VDecl->setInvalidDecl(); 3036 3037 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3038 // Don't check invalid declarations to avoid emitting useless diagnostics. 3039 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3040 // C99 6.7.8p4. All file scoped initializers need to be constant. 3041 CheckForConstantInitializer(Init, DclT); 3042 } 3043 } 3044 // If the type changed, it means we had an incomplete type that was 3045 // completed by the initializer. For example: 3046 // int ary[] = { 1, 3, 5 }; 3047 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3048 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3049 VDecl->setType(DclT); 3050 Init->setType(DclT); 3051 } 3052 3053 // Attach the initializer to the decl. 3054 VDecl->setInit(Context, Init); 3055 3056 // If the previous declaration of VDecl was a tentative definition, 3057 // remove it from the set of tentative definitions. 3058 if (VDecl->getPreviousDeclaration() && 3059 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3060 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3061 = TentativeDefinitions.find(VDecl->getDeclName()); 3062 assert(Pos != TentativeDefinitions.end() && 3063 "Unrecorded tentative definition?"); 3064 TentativeDefinitions.erase(Pos); 3065 } 3066 3067 return; 3068} 3069 3070void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3071 bool TypeContainsUndeducedAuto) { 3072 Decl *RealDecl = dcl.getAs<Decl>(); 3073 3074 // If there is no declaration, there was an error parsing it. Just ignore it. 3075 if (RealDecl == 0) 3076 return; 3077 3078 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3079 QualType Type = Var->getType(); 3080 3081 // Record tentative definitions. 3082 if (Var->isTentativeDefinition(Context)) 3083 TentativeDefinitions[Var->getDeclName()] = Var; 3084 3085 // C++ [dcl.init.ref]p3: 3086 // The initializer can be omitted for a reference only in a 3087 // parameter declaration (8.3.5), in the declaration of a 3088 // function return type, in the declaration of a class member 3089 // within its class declaration (9.2), and where the extern 3090 // specifier is explicitly used. 3091 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3092 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3093 << Var->getDeclName() 3094 << SourceRange(Var->getLocation(), Var->getLocation()); 3095 Var->setInvalidDecl(); 3096 return; 3097 } 3098 3099 // C++0x [dcl.spec.auto]p3 3100 if (TypeContainsUndeducedAuto) { 3101 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3102 << Var->getDeclName() << Type; 3103 Var->setInvalidDecl(); 3104 return; 3105 } 3106 3107 // C++ [dcl.init]p9: 3108 // 3109 // If no initializer is specified for an object, and the object 3110 // is of (possibly cv-qualified) non-POD class type (or array 3111 // thereof), the object shall be default-initialized; if the 3112 // object is of const-qualified type, the underlying class type 3113 // shall have a user-declared default constructor. 3114 if (getLangOptions().CPlusPlus) { 3115 QualType InitType = Type; 3116 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3117 InitType = Array->getElementType(); 3118 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3119 InitType->isRecordType() && !InitType->isDependentType()) { 3120 CXXRecordDecl *RD = 3121 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 3122 CXXConstructorDecl *Constructor = 0; 3123 if (!RequireCompleteType(Var->getLocation(), InitType, 3124 diag::err_invalid_incomplete_type_use)) 3125 Constructor 3126 = PerformInitializationByConstructor(InitType, 0, 0, 3127 Var->getLocation(), 3128 SourceRange(Var->getLocation(), 3129 Var->getLocation()), 3130 Var->getDeclName(), 3131 IK_Default); 3132 if (!Constructor) 3133 Var->setInvalidDecl(); 3134 else { 3135 if (!RD->hasTrivialConstructor()) 3136 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 3137 // FIXME. Must do all that is needed to destroy the object 3138 // on scope exit. For now, just mark the destructor as used. 3139 MarkDestructorReferenced(Var->getLocation(), InitType); 3140 } 3141 } 3142 } 3143 3144#if 0 3145 // FIXME: Temporarily disabled because we are not properly parsing 3146 // linkage specifications on declarations, e.g., 3147 // 3148 // extern "C" const CGPoint CGPointerZero; 3149 // 3150 // C++ [dcl.init]p9: 3151 // 3152 // If no initializer is specified for an object, and the 3153 // object is of (possibly cv-qualified) non-POD class type (or 3154 // array thereof), the object shall be default-initialized; if 3155 // the object is of const-qualified type, the underlying class 3156 // type shall have a user-declared default 3157 // constructor. Otherwise, if no initializer is specified for 3158 // an object, the object and its subobjects, if any, have an 3159 // indeterminate initial value; if the object or any of its 3160 // subobjects are of const-qualified type, the program is 3161 // ill-formed. 3162 // 3163 // This isn't technically an error in C, so we don't diagnose it. 3164 // 3165 // FIXME: Actually perform the POD/user-defined default 3166 // constructor check. 3167 if (getLangOptions().CPlusPlus && 3168 Context.getCanonicalType(Type).isConstQualified() && 3169 !Var->hasExternalStorage()) 3170 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3171 << Var->getName() 3172 << SourceRange(Var->getLocation(), Var->getLocation()); 3173#endif 3174 } 3175} 3176 3177Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3178 DeclPtrTy *Group, 3179 unsigned NumDecls) { 3180 llvm::SmallVector<Decl*, 8> Decls; 3181 3182 if (DS.isTypeSpecOwned()) 3183 Decls.push_back((Decl*)DS.getTypeRep()); 3184 3185 for (unsigned i = 0; i != NumDecls; ++i) 3186 if (Decl *D = Group[i].getAs<Decl>()) 3187 Decls.push_back(D); 3188 3189 // Perform semantic analysis that depends on having fully processed both 3190 // the declarator and initializer. 3191 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3192 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3193 if (!IDecl) 3194 continue; 3195 QualType T = IDecl->getType(); 3196 3197 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3198 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3199 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3200 if (!IDecl->isInvalidDecl() && 3201 RequireCompleteType(IDecl->getLocation(), T, 3202 diag::err_typecheck_decl_incomplete_type)) 3203 IDecl->setInvalidDecl(); 3204 } 3205 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3206 // object that has file scope without an initializer, and without a 3207 // storage-class specifier or with the storage-class specifier "static", 3208 // constitutes a tentative definition. Note: A tentative definition with 3209 // external linkage is valid (C99 6.2.2p5). 3210 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3211 if (const IncompleteArrayType *ArrayT 3212 = Context.getAsIncompleteArrayType(T)) { 3213 if (RequireCompleteType(IDecl->getLocation(), 3214 ArrayT->getElementType(), 3215 diag::err_illegal_decl_array_incomplete_type)) 3216 IDecl->setInvalidDecl(); 3217 } 3218 else if (IDecl->getStorageClass() == VarDecl::Static) { 3219 // C99 6.9.2p3: If the declaration of an identifier for an object is 3220 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3221 // declared type shall not be an incomplete type. 3222 // NOTE: code such as the following 3223 // static struct s; 3224 // struct s { int a; }; 3225 // is accepted by gcc. Hence here we issue a warning instead of 3226 // an error and we do not invalidate the static declaration. 3227 // NOTE: to avoid multiple warnings, only check the first declaration. 3228 if (IDecl->getPreviousDeclaration() == 0) 3229 RequireCompleteType(IDecl->getLocation(), T, 3230 diag::ext_typecheck_decl_incomplete_type); 3231 } 3232 } 3233 } 3234 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3235 Decls.data(), Decls.size())); 3236} 3237 3238 3239/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3240/// to introduce parameters into function prototype scope. 3241Sema::DeclPtrTy 3242Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3243 const DeclSpec &DS = D.getDeclSpec(); 3244 3245 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3246 VarDecl::StorageClass StorageClass = VarDecl::None; 3247 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3248 StorageClass = VarDecl::Register; 3249 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3250 Diag(DS.getStorageClassSpecLoc(), 3251 diag::err_invalid_storage_class_in_func_decl); 3252 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3253 } 3254 3255 if (D.getDeclSpec().isThreadSpecified()) 3256 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3257 3258 DiagnoseFunctionSpecifiers(D); 3259 3260 // Check that there are no default arguments inside the type of this 3261 // parameter (C++ only). 3262 if (getLangOptions().CPlusPlus) 3263 CheckExtraCXXDefaultArguments(D); 3264 3265 TagDecl *OwnedDecl = 0; 3266 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 3267 3268 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3269 // C++ [dcl.fct]p6: 3270 // Types shall not be defined in return or parameter types. 3271 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3272 << Context.getTypeDeclType(OwnedDecl); 3273 } 3274 3275 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3276 // Can this happen for params? We already checked that they don't conflict 3277 // among each other. Here they can only shadow globals, which is ok. 3278 IdentifierInfo *II = D.getIdentifier(); 3279 if (II) { 3280 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3281 if (PrevDecl->isTemplateParameter()) { 3282 // Maybe we will complain about the shadowed template parameter. 3283 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3284 // Just pretend that we didn't see the previous declaration. 3285 PrevDecl = 0; 3286 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3287 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3288 3289 // Recover by removing the name 3290 II = 0; 3291 D.SetIdentifier(0, D.getIdentifierLoc()); 3292 } 3293 } 3294 } 3295 3296 // Parameters can not be abstract class types. 3297 // For record types, this is done by the AbstractClassUsageDiagnoser once 3298 // the class has been completely parsed. 3299 if (!CurContext->isRecord() && 3300 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3301 diag::err_abstract_type_in_decl, 3302 AbstractParamType)) 3303 D.setInvalidType(true); 3304 3305 QualType T = adjustParameterType(parmDeclType); 3306 3307 ParmVarDecl *New; 3308 if (T == parmDeclType) // parameter type did not need adjustment 3309 New = ParmVarDecl::Create(Context, CurContext, 3310 D.getIdentifierLoc(), II, 3311 parmDeclType, StorageClass, 3312 0); 3313 else // keep track of both the adjusted and unadjusted types 3314 New = OriginalParmVarDecl::Create(Context, CurContext, 3315 D.getIdentifierLoc(), II, T, 3316 parmDeclType, StorageClass, 0); 3317 3318 if (D.isInvalidType()) 3319 New->setInvalidDecl(); 3320 3321 // Parameter declarators cannot be interface types. All ObjC objects are 3322 // passed by reference. 3323 if (T->isObjCInterfaceType()) { 3324 Diag(D.getIdentifierLoc(), 3325 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3326 New->setInvalidDecl(); 3327 } 3328 3329 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3330 if (D.getCXXScopeSpec().isSet()) { 3331 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3332 << D.getCXXScopeSpec().getRange(); 3333 New->setInvalidDecl(); 3334 } 3335 3336 // Add the parameter declaration into this scope. 3337 S->AddDecl(DeclPtrTy::make(New)); 3338 if (II) 3339 IdResolver.AddDecl(New); 3340 3341 ProcessDeclAttributes(S, New, D); 3342 3343 if (New->hasAttr<BlocksAttr>()) { 3344 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3345 } 3346 return DeclPtrTy::make(New); 3347} 3348 3349void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3350 SourceLocation LocAfterDecls) { 3351 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3352 "Not a function declarator!"); 3353 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3354 3355 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3356 // for a K&R function. 3357 if (!FTI.hasPrototype) { 3358 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3359 --i; 3360 if (FTI.ArgInfo[i].Param == 0) { 3361 std::string Code = " int "; 3362 Code += FTI.ArgInfo[i].Ident->getName(); 3363 Code += ";\n"; 3364 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3365 << FTI.ArgInfo[i].Ident 3366 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3367 3368 // Implicitly declare the argument as type 'int' for lack of a better 3369 // type. 3370 DeclSpec DS; 3371 const char* PrevSpec; // unused 3372 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3373 PrevSpec); 3374 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3375 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3376 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3377 } 3378 } 3379 } 3380} 3381 3382Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3383 Declarator &D) { 3384 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3385 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3386 "Not a function declarator!"); 3387 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3388 3389 if (FTI.hasPrototype) { 3390 // FIXME: Diagnose arguments without names in C. 3391 } 3392 3393 Scope *ParentScope = FnBodyScope->getParent(); 3394 3395 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3396 MultiTemplateParamsArg(*this), 3397 /*IsFunctionDefinition=*/true); 3398 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3399} 3400 3401Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3402 if (!D) 3403 return D; 3404 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3405 3406 CurFunctionNeedsScopeChecking = false; 3407 3408 // See if this is a redefinition. 3409 const FunctionDecl *Definition; 3410 if (FD->getBody(Definition)) { 3411 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3412 Diag(Definition->getLocation(), diag::note_previous_definition); 3413 } 3414 3415 // Builtin functions cannot be defined. 3416 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3417 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3418 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3419 FD->setInvalidDecl(); 3420 } 3421 } 3422 3423 // The return type of a function definition must be complete 3424 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3425 QualType ResultType = FD->getResultType(); 3426 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3427 !FD->isInvalidDecl() && 3428 RequireCompleteType(FD->getLocation(), ResultType, 3429 diag::err_func_def_incomplete_result)) 3430 FD->setInvalidDecl(); 3431 3432 // GNU warning -Wmissing-prototypes: 3433 // Warn if a global function is defined without a previous 3434 // prototype declaration. This warning is issued even if the 3435 // definition itself provides a prototype. The aim is to detect 3436 // global functions that fail to be declared in header files. 3437 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3438 !FD->isMain()) { 3439 bool MissingPrototype = true; 3440 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3441 Prev; Prev = Prev->getPreviousDeclaration()) { 3442 // Ignore any declarations that occur in function or method 3443 // scope, because they aren't visible from the header. 3444 if (Prev->getDeclContext()->isFunctionOrMethod()) 3445 continue; 3446 3447 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3448 break; 3449 } 3450 3451 if (MissingPrototype) 3452 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3453 } 3454 3455 if (FnBodyScope) 3456 PushDeclContext(FnBodyScope, FD); 3457 3458 // Check the validity of our function parameters 3459 CheckParmsForFunctionDef(FD); 3460 3461 // Introduce our parameters into the function scope 3462 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3463 ParmVarDecl *Param = FD->getParamDecl(p); 3464 Param->setOwningFunction(FD); 3465 3466 // If this has an identifier, add it to the scope stack. 3467 if (Param->getIdentifier() && FnBodyScope) 3468 PushOnScopeChains(Param, FnBodyScope); 3469 } 3470 3471 // Checking attributes of current function definition 3472 // dllimport attribute. 3473 if (FD->getAttr<DLLImportAttr>() && 3474 (!FD->getAttr<DLLExportAttr>())) { 3475 // dllimport attribute cannot be applied to definition. 3476 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3477 Diag(FD->getLocation(), 3478 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3479 << "dllimport"; 3480 FD->setInvalidDecl(); 3481 return DeclPtrTy::make(FD); 3482 } else { 3483 // If a symbol previously declared dllimport is later defined, the 3484 // attribute is ignored in subsequent references, and a warning is 3485 // emitted. 3486 Diag(FD->getLocation(), 3487 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3488 << FD->getNameAsCString() << "dllimport"; 3489 } 3490 } 3491 return DeclPtrTy::make(FD); 3492} 3493 3494Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3495 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3496} 3497 3498Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3499 bool IsInstantiation) { 3500 Decl *dcl = D.getAs<Decl>(); 3501 Stmt *Body = BodyArg.takeAs<Stmt>(); 3502 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3503 FD->setBody(Body); 3504 if (!FD->isMain()) 3505 // C and C++ allow for main to automagically return 0. 3506 CheckFallThroughForFunctionDef(FD, Body); 3507 3508 if (!FD->isInvalidDecl()) 3509 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3510 3511 // C++ [basic.def.odr]p2: 3512 // [...] A virtual member function is used if it is not pure. [...] 3513 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3514 if (Method->isVirtual() && !Method->isPure()) 3515 MarkDeclarationReferenced(Method->getLocation(), Method); 3516 3517 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3518 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3519 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3520 MD->setBody(Body); 3521 CheckFallThroughForFunctionDef(MD, Body); 3522 MD->setEndLoc(Body->getLocEnd()); 3523 3524 if (!MD->isInvalidDecl()) 3525 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3526 } else { 3527 Body->Destroy(Context); 3528 return DeclPtrTy(); 3529 } 3530 if (!IsInstantiation) 3531 PopDeclContext(); 3532 3533 // Verify and clean out per-function state. 3534 3535 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3536 3537 // Check goto/label use. 3538 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3539 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3540 LabelStmt *L = I->second; 3541 3542 // Verify that we have no forward references left. If so, there was a goto 3543 // or address of a label taken, but no definition of it. Label fwd 3544 // definitions are indicated with a null substmt. 3545 if (L->getSubStmt() != 0) 3546 continue; 3547 3548 // Emit error. 3549 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3550 3551 // At this point, we have gotos that use the bogus label. Stitch it into 3552 // the function body so that they aren't leaked and that the AST is well 3553 // formed. 3554 if (Body == 0) { 3555 // The whole function wasn't parsed correctly, just delete this. 3556 L->Destroy(Context); 3557 continue; 3558 } 3559 3560 // Otherwise, the body is valid: we want to stitch the label decl into the 3561 // function somewhere so that it is properly owned and so that the goto 3562 // has a valid target. Do this by creating a new compound stmt with the 3563 // label in it. 3564 3565 // Give the label a sub-statement. 3566 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3567 3568 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3569 cast<CXXTryStmt>(Body)->getTryBlock() : 3570 cast<CompoundStmt>(Body); 3571 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3572 Elements.push_back(L); 3573 Compound->setStmts(Context, &Elements[0], Elements.size()); 3574 } 3575 FunctionLabelMap.clear(); 3576 3577 if (!Body) return D; 3578 3579 // Verify that that gotos and switch cases don't jump into scopes illegally. 3580 if (CurFunctionNeedsScopeChecking) 3581 DiagnoseInvalidJumps(Body); 3582 3583 // C++ constructors that have function-try-blocks can't have return 3584 // statements in the handlers of that block. (C++ [except.handle]p14) 3585 // Verify this. 3586 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3587 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3588 3589 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3590 Destructor->computeBaseOrMembersToDestroy(Context); 3591 return D; 3592} 3593 3594/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3595/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3596NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3597 IdentifierInfo &II, Scope *S) { 3598 // Before we produce a declaration for an implicitly defined 3599 // function, see whether there was a locally-scoped declaration of 3600 // this name as a function or variable. If so, use that 3601 // (non-visible) declaration, and complain about it. 3602 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3603 = LocallyScopedExternalDecls.find(&II); 3604 if (Pos != LocallyScopedExternalDecls.end()) { 3605 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3606 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3607 return Pos->second; 3608 } 3609 3610 // Extension in C99. Legal in C90, but warn about it. 3611 if (getLangOptions().C99) 3612 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3613 else 3614 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3615 3616 // FIXME: handle stuff like: 3617 // void foo() { extern float X(); } 3618 // void bar() { X(); } <-- implicit decl for X in another scope. 3619 3620 // Set a Declarator for the implicit definition: int foo(); 3621 const char *Dummy; 3622 DeclSpec DS; 3623 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3624 Error = Error; // Silence warning. 3625 assert(!Error && "Error setting up implicit decl!"); 3626 Declarator D(DS, Declarator::BlockContext); 3627 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3628 0, 0, false, SourceLocation(), 3629 false, 0,0,0, Loc, D), 3630 SourceLocation()); 3631 D.SetIdentifier(&II, Loc); 3632 3633 // Insert this function into translation-unit scope. 3634 3635 DeclContext *PrevDC = CurContext; 3636 CurContext = Context.getTranslationUnitDecl(); 3637 3638 FunctionDecl *FD = 3639 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3640 FD->setImplicit(); 3641 3642 CurContext = PrevDC; 3643 3644 AddKnownFunctionAttributes(FD); 3645 3646 return FD; 3647} 3648 3649/// \brief Adds any function attributes that we know a priori based on 3650/// the declaration of this function. 3651/// 3652/// These attributes can apply both to implicitly-declared builtins 3653/// (like __builtin___printf_chk) or to library-declared functions 3654/// like NSLog or printf. 3655void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3656 if (FD->isInvalidDecl()) 3657 return; 3658 3659 // If this is a built-in function, map its builtin attributes to 3660 // actual attributes. 3661 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3662 // Handle printf-formatting attributes. 3663 unsigned FormatIdx; 3664 bool HasVAListArg; 3665 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3666 if (!FD->getAttr<FormatAttr>()) 3667 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3668 HasVAListArg ? 0 : FormatIdx + 2)); 3669 } 3670 3671 // Mark const if we don't care about errno and that is the only 3672 // thing preventing the function from being const. This allows 3673 // IRgen to use LLVM intrinsics for such functions. 3674 if (!getLangOptions().MathErrno && 3675 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3676 if (!FD->getAttr<ConstAttr>()) 3677 FD->addAttr(::new (Context) ConstAttr()); 3678 } 3679 3680 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 3681 FD->addAttr(::new (Context) NoReturnAttr()); 3682 } 3683 3684 IdentifierInfo *Name = FD->getIdentifier(); 3685 if (!Name) 3686 return; 3687 if ((!getLangOptions().CPlusPlus && 3688 FD->getDeclContext()->isTranslationUnit()) || 3689 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3690 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3691 LinkageSpecDecl::lang_c)) { 3692 // Okay: this could be a libc/libm/Objective-C function we know 3693 // about. 3694 } else 3695 return; 3696 3697 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3698 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3699 // FIXME: We known better than our headers. 3700 const_cast<FormatAttr *>(Format)->setType("printf"); 3701 } else 3702 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3703 Name->isStr("NSLogv") ? 0 : 2)); 3704 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3705 if (!FD->getAttr<FormatAttr>()) 3706 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3707 Name->isStr("vasprintf") ? 0 : 3)); 3708 } 3709} 3710 3711TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3712 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3713 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3714 3715 // Scope manipulation handled by caller. 3716 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3717 D.getIdentifierLoc(), 3718 D.getIdentifier(), 3719 T); 3720 3721 if (TagType *TT = dyn_cast<TagType>(T)) { 3722 TagDecl *TD = TT->getDecl(); 3723 3724 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3725 // keep track of the TypedefDecl. 3726 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3727 TD->setTypedefForAnonDecl(NewTD); 3728 } 3729 3730 if (D.isInvalidType()) 3731 NewTD->setInvalidDecl(); 3732 return NewTD; 3733} 3734 3735 3736/// \brief Determine whether a tag with a given kind is acceptable 3737/// as a redeclaration of the given tag declaration. 3738/// 3739/// \returns true if the new tag kind is acceptable, false otherwise. 3740bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3741 TagDecl::TagKind NewTag, 3742 SourceLocation NewTagLoc, 3743 const IdentifierInfo &Name) { 3744 // C++ [dcl.type.elab]p3: 3745 // The class-key or enum keyword present in the 3746 // elaborated-type-specifier shall agree in kind with the 3747 // declaration to which the name in theelaborated-type-specifier 3748 // refers. This rule also applies to the form of 3749 // elaborated-type-specifier that declares a class-name or 3750 // friend class since it can be construed as referring to the 3751 // definition of the class. Thus, in any 3752 // elaborated-type-specifier, the enum keyword shall be used to 3753 // refer to an enumeration (7.2), the union class-keyshall be 3754 // used to refer to a union (clause 9), and either the class or 3755 // struct class-key shall be used to refer to a class (clause 9) 3756 // declared using the class or struct class-key. 3757 TagDecl::TagKind OldTag = Previous->getTagKind(); 3758 if (OldTag == NewTag) 3759 return true; 3760 3761 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3762 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3763 // Warn about the struct/class tag mismatch. 3764 bool isTemplate = false; 3765 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3766 isTemplate = Record->getDescribedClassTemplate(); 3767 3768 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3769 << (NewTag == TagDecl::TK_class) 3770 << isTemplate << &Name 3771 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3772 OldTag == TagDecl::TK_class? "class" : "struct"); 3773 Diag(Previous->getLocation(), diag::note_previous_use); 3774 return true; 3775 } 3776 return false; 3777} 3778 3779/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3780/// former case, Name will be non-null. In the later case, Name will be null. 3781/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3782/// reference/declaration/definition of a tag. 3783Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3784 SourceLocation KWLoc, const CXXScopeSpec &SS, 3785 IdentifierInfo *Name, SourceLocation NameLoc, 3786 AttributeList *Attr, AccessSpecifier AS, 3787 MultiTemplateParamsArg TemplateParameterLists, 3788 bool &OwnedDecl) { 3789 // If this is not a definition, it must have a name. 3790 assert((Name != 0 || TK == TK_Definition) && 3791 "Nameless record must be a definition!"); 3792 3793 OwnedDecl = false; 3794 TagDecl::TagKind Kind; 3795 switch (TagSpec) { 3796 default: assert(0 && "Unknown tag type!"); 3797 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3798 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3799 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3800 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3801 } 3802 3803 if (TK != TK_Reference) { 3804 if (TemplateParameterList *TemplateParams 3805 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3806 (TemplateParameterList**)TemplateParameterLists.get(), 3807 TemplateParameterLists.size())) { 3808 if (TemplateParams->size() > 0) { 3809 // This is a declaration or definition of a class template (which may 3810 // be a member of another template). 3811 OwnedDecl = false; 3812 DeclResult Result = CheckClassTemplate(S, TagSpec, TK, KWLoc, 3813 SS, Name, NameLoc, Attr, 3814 move(TemplateParameterLists), 3815 AS); 3816 return Result.get(); 3817 } else { 3818 // FIXME: diagnose the extraneous 'template<>', once we recover 3819 // slightly better in ParseTemplate.cpp from bogus template 3820 // parameters. 3821 } 3822 } 3823 } 3824 3825 DeclContext *SearchDC = CurContext; 3826 DeclContext *DC = CurContext; 3827 NamedDecl *PrevDecl = 0; 3828 3829 bool Invalid = false; 3830 3831 if (Name && SS.isNotEmpty()) { 3832 // We have a nested-name tag ('struct foo::bar'). 3833 3834 // Check for invalid 'foo::'. 3835 if (SS.isInvalid()) { 3836 Name = 0; 3837 goto CreateNewDecl; 3838 } 3839 3840 if (RequireCompleteDeclContext(SS)) 3841 return DeclPtrTy::make((Decl *)0); 3842 3843 DC = computeDeclContext(SS, true); 3844 SearchDC = DC; 3845 // Look-up name inside 'foo::'. 3846 PrevDecl 3847 = dyn_cast_or_null<TagDecl>( 3848 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3849 3850 // A tag 'foo::bar' must already exist. 3851 if (PrevDecl == 0) { 3852 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3853 Name = 0; 3854 Invalid = true; 3855 goto CreateNewDecl; 3856 } 3857 } else if (Name) { 3858 // If this is a named struct, check to see if there was a previous forward 3859 // declaration or definition. 3860 // FIXME: We're looking into outer scopes here, even when we 3861 // shouldn't be. Doing so can result in ambiguities that we 3862 // shouldn't be diagnosing. 3863 LookupResult R = LookupName(S, Name, LookupTagName, 3864 /*RedeclarationOnly=*/(TK != TK_Reference)); 3865 if (R.isAmbiguous()) { 3866 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3867 // FIXME: This is not best way to recover from case like: 3868 // 3869 // struct S s; 3870 // 3871 // causes needless "incomplete type" error later. 3872 Name = 0; 3873 PrevDecl = 0; 3874 Invalid = true; 3875 } 3876 else 3877 PrevDecl = R; 3878 3879 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3880 // FIXME: This makes sure that we ignore the contexts associated 3881 // with C structs, unions, and enums when looking for a matching 3882 // tag declaration or definition. See the similar lookup tweak 3883 // in Sema::LookupName; is there a better way to deal with this? 3884 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3885 SearchDC = SearchDC->getParent(); 3886 } 3887 } 3888 3889 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3890 // Maybe we will complain about the shadowed template parameter. 3891 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3892 // Just pretend that we didn't see the previous declaration. 3893 PrevDecl = 0; 3894 } 3895 3896 if (PrevDecl) { 3897 // Check whether the previous declaration is usable. 3898 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3899 3900 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3901 // If this is a use of a previous tag, or if the tag is already declared 3902 // in the same scope (so that the definition/declaration completes or 3903 // rementions the tag), reuse the decl. 3904 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3905 // Make sure that this wasn't declared as an enum and now used as a 3906 // struct or something similar. 3907 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3908 bool SafeToContinue 3909 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3910 Kind != TagDecl::TK_enum); 3911 if (SafeToContinue) 3912 Diag(KWLoc, diag::err_use_with_wrong_tag) 3913 << Name 3914 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3915 PrevTagDecl->getKindName()); 3916 else 3917 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3918 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3919 3920 if (SafeToContinue) 3921 Kind = PrevTagDecl->getTagKind(); 3922 else { 3923 // Recover by making this an anonymous redefinition. 3924 Name = 0; 3925 PrevDecl = 0; 3926 Invalid = true; 3927 } 3928 } 3929 3930 if (!Invalid) { 3931 // If this is a use, just return the declaration we found. 3932 3933 // FIXME: In the future, return a variant or some other clue 3934 // for the consumer of this Decl to know it doesn't own it. 3935 // For our current ASTs this shouldn't be a problem, but will 3936 // need to be changed with DeclGroups. 3937 if (TK == TK_Reference) 3938 return DeclPtrTy::make(PrevDecl); 3939 3940 // Diagnose attempts to redefine a tag. 3941 if (TK == TK_Definition) { 3942 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3943 Diag(NameLoc, diag::err_redefinition) << Name; 3944 Diag(Def->getLocation(), diag::note_previous_definition); 3945 // If this is a redefinition, recover by making this 3946 // struct be anonymous, which will make any later 3947 // references get the previous definition. 3948 Name = 0; 3949 PrevDecl = 0; 3950 Invalid = true; 3951 } else { 3952 // If the type is currently being defined, complain 3953 // about a nested redefinition. 3954 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3955 if (Tag->isBeingDefined()) { 3956 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3957 Diag(PrevTagDecl->getLocation(), 3958 diag::note_previous_definition); 3959 Name = 0; 3960 PrevDecl = 0; 3961 Invalid = true; 3962 } 3963 } 3964 3965 // Okay, this is definition of a previously declared or referenced 3966 // tag PrevDecl. We're going to create a new Decl for it. 3967 } 3968 } 3969 // If we get here we have (another) forward declaration or we 3970 // have a definition. Just create a new decl. 3971 } else { 3972 // If we get here, this is a definition of a new tag type in a nested 3973 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3974 // new decl/type. We set PrevDecl to NULL so that the entities 3975 // have distinct types. 3976 PrevDecl = 0; 3977 } 3978 // If we get here, we're going to create a new Decl. If PrevDecl 3979 // is non-NULL, it's a definition of the tag declared by 3980 // PrevDecl. If it's NULL, we have a new definition. 3981 } else { 3982 // PrevDecl is a namespace, template, or anything else 3983 // that lives in the IDNS_Tag identifier namespace. 3984 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3985 // The tag name clashes with a namespace name, issue an error and 3986 // recover by making this tag be anonymous. 3987 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3988 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3989 Name = 0; 3990 PrevDecl = 0; 3991 Invalid = true; 3992 } else { 3993 // The existing declaration isn't relevant to us; we're in a 3994 // new scope, so clear out the previous declaration. 3995 PrevDecl = 0; 3996 } 3997 } 3998 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3999 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4000 // C++ [basic.scope.pdecl]p5: 4001 // -- for an elaborated-type-specifier of the form 4002 // 4003 // class-key identifier 4004 // 4005 // if the elaborated-type-specifier is used in the 4006 // decl-specifier-seq or parameter-declaration-clause of a 4007 // function defined in namespace scope, the identifier is 4008 // declared as a class-name in the namespace that contains 4009 // the declaration; otherwise, except as a friend 4010 // declaration, the identifier is declared in the smallest 4011 // non-class, non-function-prototype scope that contains the 4012 // declaration. 4013 // 4014 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4015 // C structs and unions. 4016 // 4017 // GNU C also supports this behavior as part of its incomplete 4018 // enum types extension, while GNU C++ does not. 4019 // 4020 // Find the context where we'll be declaring the tag. 4021 // FIXME: We would like to maintain the current DeclContext as the 4022 // lexical context, 4023 while (SearchDC->isRecord()) 4024 SearchDC = SearchDC->getParent(); 4025 4026 // Find the scope where we'll be declaring the tag. 4027 while (S->isClassScope() || 4028 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4029 ((S->getFlags() & Scope::DeclScope) == 0) || 4030 (S->getEntity() && 4031 ((DeclContext *)S->getEntity())->isTransparentContext())) 4032 S = S->getParent(); 4033 } 4034 4035CreateNewDecl: 4036 4037 // If there is an identifier, use the location of the identifier as the 4038 // location of the decl, otherwise use the location of the struct/union 4039 // keyword. 4040 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4041 4042 // Otherwise, create a new declaration. If there is a previous 4043 // declaration of the same entity, the two will be linked via 4044 // PrevDecl. 4045 TagDecl *New; 4046 4047 if (Kind == TagDecl::TK_enum) { 4048 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4049 // enum X { A, B, C } D; D should chain to X. 4050 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4051 cast_or_null<EnumDecl>(PrevDecl)); 4052 // If this is an undefined enum, warn. 4053 if (TK != TK_Definition && !Invalid) { 4054 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4055 : diag::ext_forward_ref_enum; 4056 Diag(Loc, DK); 4057 } 4058 } else { 4059 // struct/union/class 4060 4061 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4062 // struct X { int A; } D; D should chain to X. 4063 if (getLangOptions().CPlusPlus) 4064 // FIXME: Look for a way to use RecordDecl for simple structs. 4065 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4066 cast_or_null<CXXRecordDecl>(PrevDecl)); 4067 else 4068 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4069 cast_or_null<RecordDecl>(PrevDecl)); 4070 } 4071 4072 if (Kind != TagDecl::TK_enum) { 4073 // Handle #pragma pack: if the #pragma pack stack has non-default 4074 // alignment, make up a packed attribute for this decl. These 4075 // attributes are checked when the ASTContext lays out the 4076 // structure. 4077 // 4078 // It is important for implementing the correct semantics that this 4079 // happen here (in act on tag decl). The #pragma pack stack is 4080 // maintained as a result of parser callbacks which can occur at 4081 // many points during the parsing of a struct declaration (because 4082 // the #pragma tokens are effectively skipped over during the 4083 // parsing of the struct). 4084 if (unsigned Alignment = getPragmaPackAlignment()) 4085 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 4086 } 4087 4088 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4089 // C++ [dcl.typedef]p3: 4090 // [...] Similarly, in a given scope, a class or enumeration 4091 // shall not be declared with the same name as a typedef-name 4092 // that is declared in that scope and refers to a type other 4093 // than the class or enumeration itself. 4094 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4095 TypedefDecl *PrevTypedef = 0; 4096 if (Lookup.getKind() == LookupResult::Found) 4097 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4098 4099 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4100 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4101 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4102 Diag(Loc, diag::err_tag_definition_of_typedef) 4103 << Context.getTypeDeclType(New) 4104 << PrevTypedef->getUnderlyingType(); 4105 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4106 Invalid = true; 4107 } 4108 } 4109 4110 if (Invalid) 4111 New->setInvalidDecl(); 4112 4113 if (Attr) 4114 ProcessDeclAttributeList(S, New, Attr); 4115 4116 // If we're declaring or defining a tag in function prototype scope 4117 // in C, note that this type can only be used within the function. 4118 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4119 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4120 4121 // Set the lexical context. If the tag has a C++ scope specifier, the 4122 // lexical context will be different from the semantic context. 4123 New->setLexicalDeclContext(CurContext); 4124 4125 // Set the access specifier. 4126 if (!Invalid) 4127 SetMemberAccessSpecifier(New, PrevDecl, AS); 4128 4129 if (TK == TK_Definition) 4130 New->startDefinition(); 4131 4132 // If this has an identifier, add it to the scope stack. 4133 if (Name) { 4134 S = getNonFieldDeclScope(S); 4135 PushOnScopeChains(New, S); 4136 } else { 4137 CurContext->addDecl(New); 4138 } 4139 4140 // If this is the C FILE type, notify the AST context. 4141 if (IdentifierInfo *II = New->getIdentifier()) 4142 if (!New->isInvalidDecl() && 4143 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4144 II->isStr("FILE")) 4145 Context.setFILEDecl(New); 4146 4147 OwnedDecl = true; 4148 return DeclPtrTy::make(New); 4149} 4150 4151void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4152 AdjustDeclIfTemplate(TagD); 4153 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4154 4155 // Enter the tag context. 4156 PushDeclContext(S, Tag); 4157 4158 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4159 FieldCollector->StartClass(); 4160 4161 if (Record->getIdentifier()) { 4162 // C++ [class]p2: 4163 // [...] The class-name is also inserted into the scope of the 4164 // class itself; this is known as the injected-class-name. For 4165 // purposes of access checking, the injected-class-name is treated 4166 // as if it were a public member name. 4167 CXXRecordDecl *InjectedClassName 4168 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4169 CurContext, Record->getLocation(), 4170 Record->getIdentifier(), 4171 Record->getTagKeywordLoc(), 4172 Record); 4173 InjectedClassName->setImplicit(); 4174 InjectedClassName->setAccess(AS_public); 4175 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4176 InjectedClassName->setDescribedClassTemplate(Template); 4177 PushOnScopeChains(InjectedClassName, S); 4178 assert(InjectedClassName->isInjectedClassName() && 4179 "Broken injected-class-name"); 4180 } 4181 } 4182} 4183 4184void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4185 SourceLocation RBraceLoc) { 4186 AdjustDeclIfTemplate(TagD); 4187 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4188 Tag->setRBraceLoc(RBraceLoc); 4189 4190 if (isa<CXXRecordDecl>(Tag)) 4191 FieldCollector->FinishClass(); 4192 4193 // Exit this scope of this tag's definition. 4194 PopDeclContext(); 4195 4196 // Notify the consumer that we've defined a tag. 4197 Consumer.HandleTagDeclDefinition(Tag); 4198} 4199 4200// Note that FieldName may be null for anonymous bitfields. 4201bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4202 QualType FieldTy, const Expr *BitWidth) { 4203 4204 // C99 6.7.2.1p4 - verify the field type. 4205 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4206 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4207 // Handle incomplete types with specific error. 4208 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4209 return true; 4210 if (FieldName) 4211 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4212 << FieldName << FieldTy << BitWidth->getSourceRange(); 4213 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4214 << FieldTy << BitWidth->getSourceRange(); 4215 } 4216 4217 // If the bit-width is type- or value-dependent, don't try to check 4218 // it now. 4219 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4220 return false; 4221 4222 llvm::APSInt Value; 4223 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4224 return true; 4225 4226 // Zero-width bitfield is ok for anonymous field. 4227 if (Value == 0 && FieldName) 4228 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4229 4230 if (Value.isSigned() && Value.isNegative()) { 4231 if (FieldName) 4232 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4233 << FieldName << Value.toString(10); 4234 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4235 << Value.toString(10); 4236 } 4237 4238 if (!FieldTy->isDependentType()) { 4239 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4240 if (Value.getZExtValue() > TypeSize) { 4241 if (FieldName) 4242 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4243 << FieldName << (unsigned)TypeSize; 4244 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4245 << (unsigned)TypeSize; 4246 } 4247 } 4248 4249 return false; 4250} 4251 4252/// ActOnField - Each field of a struct/union/class is passed into this in order 4253/// to create a FieldDecl object for it. 4254Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4255 SourceLocation DeclStart, 4256 Declarator &D, ExprTy *BitfieldWidth) { 4257 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4258 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4259 AS_public); 4260 return DeclPtrTy::make(Res); 4261} 4262 4263/// HandleField - Analyze a field of a C struct or a C++ data member. 4264/// 4265FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4266 SourceLocation DeclStart, 4267 Declarator &D, Expr *BitWidth, 4268 AccessSpecifier AS) { 4269 IdentifierInfo *II = D.getIdentifier(); 4270 SourceLocation Loc = DeclStart; 4271 if (II) Loc = D.getIdentifierLoc(); 4272 4273 QualType T = GetTypeForDeclarator(D, S); 4274 if (getLangOptions().CPlusPlus) 4275 CheckExtraCXXDefaultArguments(D); 4276 4277 DiagnoseFunctionSpecifiers(D); 4278 4279 if (D.getDeclSpec().isThreadSpecified()) 4280 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4281 4282 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4283 4284 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4285 // Maybe we will complain about the shadowed template parameter. 4286 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4287 // Just pretend that we didn't see the previous declaration. 4288 PrevDecl = 0; 4289 } 4290 4291 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4292 PrevDecl = 0; 4293 4294 bool Mutable 4295 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4296 SourceLocation TSSL = D.getSourceRange().getBegin(); 4297 FieldDecl *NewFD 4298 = CheckFieldDecl(II, T, Record, Loc, Mutable, BitWidth, TSSL, 4299 AS, PrevDecl, &D); 4300 if (NewFD->isInvalidDecl() && PrevDecl) { 4301 // Don't introduce NewFD into scope; there's already something 4302 // with the same name in the same scope. 4303 } else if (II) { 4304 PushOnScopeChains(NewFD, S); 4305 } else 4306 Record->addDecl(NewFD); 4307 4308 return NewFD; 4309} 4310 4311/// \brief Build a new FieldDecl and check its well-formedness. 4312/// 4313/// This routine builds a new FieldDecl given the fields name, type, 4314/// record, etc. \p PrevDecl should refer to any previous declaration 4315/// with the same name and in the same scope as the field to be 4316/// created. 4317/// 4318/// \returns a new FieldDecl. 4319/// 4320/// \todo The Declarator argument is a hack. It will be removed once 4321FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4322 RecordDecl *Record, SourceLocation Loc, 4323 bool Mutable, Expr *BitWidth, 4324 SourceLocation TSSL, 4325 AccessSpecifier AS, NamedDecl *PrevDecl, 4326 Declarator *D) { 4327 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4328 bool InvalidDecl = false; 4329 if (D) InvalidDecl = D->isInvalidType(); 4330 4331 // If we receive a broken type, recover by assuming 'int' and 4332 // marking this declaration as invalid. 4333 if (T.isNull()) { 4334 InvalidDecl = true; 4335 T = Context.IntTy; 4336 } 4337 4338 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4339 // than a variably modified type. 4340 if (T->isVariablyModifiedType()) { 4341 bool SizeIsNegative; 4342 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4343 SizeIsNegative); 4344 if (!FixedTy.isNull()) { 4345 Diag(Loc, diag::warn_illegal_constant_array_size); 4346 T = FixedTy; 4347 } else { 4348 if (SizeIsNegative) 4349 Diag(Loc, diag::err_typecheck_negative_array_size); 4350 else 4351 Diag(Loc, diag::err_typecheck_field_variable_size); 4352 InvalidDecl = true; 4353 } 4354 } 4355 4356 // Fields can not have abstract class types 4357 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4358 AbstractFieldType)) 4359 InvalidDecl = true; 4360 4361 // If this is declared as a bit-field, check the bit-field. 4362 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 4363 InvalidDecl = true; 4364 DeleteExpr(BitWidth); 4365 BitWidth = 0; 4366 } 4367 4368 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 4369 Mutable, TSSL); 4370 if (InvalidDecl) 4371 NewFD->setInvalidDecl(); 4372 4373 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4374 Diag(Loc, diag::err_duplicate_member) << II; 4375 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4376 NewFD->setInvalidDecl(); 4377 } 4378 4379 if (getLangOptions().CPlusPlus) { 4380 QualType EltTy = Context.getBaseElementType(T); 4381 4382 if (const RecordType *RT = EltTy->getAsRecordType()) { 4383 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4384 4385 if (!RDecl->hasTrivialConstructor()) 4386 cast<CXXRecordDecl>(Record)->setHasTrivialConstructor(false); 4387 if (!RDecl->hasTrivialCopyConstructor()) 4388 cast<CXXRecordDecl>(Record)->setHasTrivialCopyConstructor(false); 4389 if (!RDecl->hasTrivialCopyAssignment()) 4390 cast<CXXRecordDecl>(Record)->setHasTrivialCopyAssignment(false); 4391 if (!RDecl->hasTrivialDestructor()) 4392 cast<CXXRecordDecl>(Record)->setHasTrivialDestructor(false); 4393 4394 // C++ 9.5p1: An object of a class with a non-trivial 4395 // constructor, a non-trivial copy constructor, a non-trivial 4396 // destructor, or a non-trivial copy assignment operator 4397 // cannot be a member of a union, nor can an array of such 4398 // objects. 4399 // TODO: C++0x alters this restriction significantly. 4400 if (Record->isUnion()) { 4401 // We check for copy constructors before constructors 4402 // because otherwise we'll never get complaints about 4403 // copy constructors. 4404 4405 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4406 4407 CXXSpecialMember member; 4408 if (!RDecl->hasTrivialCopyConstructor()) 4409 member = CXXCopyConstructor; 4410 else if (!RDecl->hasTrivialConstructor()) 4411 member = CXXDefaultConstructor; 4412 else if (!RDecl->hasTrivialCopyAssignment()) 4413 member = CXXCopyAssignment; 4414 else if (!RDecl->hasTrivialDestructor()) 4415 member = CXXDestructor; 4416 else 4417 member = invalid; 4418 4419 if (member != invalid) { 4420 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4421 DiagnoseNontrivial(RT, member); 4422 NewFD->setInvalidDecl(); 4423 } 4424 } 4425 } 4426 } 4427 4428 if (getLangOptions().CPlusPlus && !T->isPODType()) 4429 cast<CXXRecordDecl>(Record)->setPOD(false); 4430 4431 // FIXME: We need to pass in the attributes given an AST 4432 // representation, not a parser representation. 4433 if (D) 4434 // FIXME: What to pass instead of TUScope? 4435 ProcessDeclAttributes(TUScope, NewFD, *D); 4436 4437 if (T.isObjCGCWeak()) 4438 Diag(Loc, diag::warn_attribute_weak_on_field); 4439 4440 NewFD->setAccess(AS); 4441 4442 // C++ [dcl.init.aggr]p1: 4443 // An aggregate is an array or a class (clause 9) with [...] no 4444 // private or protected non-static data members (clause 11). 4445 // A POD must be an aggregate. 4446 if (getLangOptions().CPlusPlus && 4447 (AS == AS_private || AS == AS_protected)) { 4448 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4449 CXXRecord->setAggregate(false); 4450 CXXRecord->setPOD(false); 4451 } 4452 4453 return NewFD; 4454} 4455 4456/// DiagnoseNontrivial - Given that a class has a non-trivial 4457/// special member, figure out why. 4458void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4459 QualType QT(T, 0U); 4460 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4461 4462 // Check whether the member was user-declared. 4463 switch (member) { 4464 case CXXDefaultConstructor: 4465 if (RD->hasUserDeclaredConstructor()) { 4466 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4467 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4468 if (!ci->isImplicitlyDefined(Context)) { 4469 SourceLocation CtorLoc = ci->getLocation(); 4470 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4471 return; 4472 } 4473 4474 assert(0 && "found no user-declared constructors"); 4475 return; 4476 } 4477 break; 4478 4479 case CXXCopyConstructor: 4480 if (RD->hasUserDeclaredCopyConstructor()) { 4481 SourceLocation CtorLoc = 4482 RD->getCopyConstructor(Context, 0)->getLocation(); 4483 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4484 return; 4485 } 4486 break; 4487 4488 case CXXCopyAssignment: 4489 if (RD->hasUserDeclaredCopyAssignment()) { 4490 // FIXME: this should use the location of the copy 4491 // assignment, not the type. 4492 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4493 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4494 return; 4495 } 4496 break; 4497 4498 case CXXDestructor: 4499 if (RD->hasUserDeclaredDestructor()) { 4500 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4501 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4502 return; 4503 } 4504 break; 4505 } 4506 4507 typedef CXXRecordDecl::base_class_iterator base_iter; 4508 4509 // Virtual bases and members inhibit trivial copying/construction, 4510 // but not trivial destruction. 4511 if (member != CXXDestructor) { 4512 // Check for virtual bases. vbases includes indirect virtual bases, 4513 // so we just iterate through the direct bases. 4514 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4515 if (bi->isVirtual()) { 4516 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4517 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4518 return; 4519 } 4520 4521 // Check for virtual methods. 4522 typedef CXXRecordDecl::method_iterator meth_iter; 4523 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4524 ++mi) { 4525 if (mi->isVirtual()) { 4526 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4527 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4528 return; 4529 } 4530 } 4531 } 4532 4533 bool (CXXRecordDecl::*hasTrivial)() const; 4534 switch (member) { 4535 case CXXDefaultConstructor: 4536 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4537 case CXXCopyConstructor: 4538 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4539 case CXXCopyAssignment: 4540 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4541 case CXXDestructor: 4542 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4543 default: 4544 assert(0 && "unexpected special member"); return; 4545 } 4546 4547 // Check for nontrivial bases (and recurse). 4548 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4549 const RecordType *BaseRT = bi->getType()->getAsRecordType(); 4550 assert(BaseRT); 4551 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4552 if (!(BaseRecTy->*hasTrivial)()) { 4553 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4554 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4555 DiagnoseNontrivial(BaseRT, member); 4556 return; 4557 } 4558 } 4559 4560 // Check for nontrivial members (and recurse). 4561 typedef RecordDecl::field_iterator field_iter; 4562 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4563 ++fi) { 4564 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4565 if (const RecordType *EltRT = EltTy->getAsRecordType()) { 4566 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4567 4568 if (!(EltRD->*hasTrivial)()) { 4569 SourceLocation FLoc = (*fi)->getLocation(); 4570 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4571 DiagnoseNontrivial(EltRT, member); 4572 return; 4573 } 4574 } 4575 } 4576 4577 assert(0 && "found no explanation for non-trivial member"); 4578} 4579 4580/// TranslateIvarVisibility - Translate visibility from a token ID to an 4581/// AST enum value. 4582static ObjCIvarDecl::AccessControl 4583TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4584 switch (ivarVisibility) { 4585 default: assert(0 && "Unknown visitibility kind"); 4586 case tok::objc_private: return ObjCIvarDecl::Private; 4587 case tok::objc_public: return ObjCIvarDecl::Public; 4588 case tok::objc_protected: return ObjCIvarDecl::Protected; 4589 case tok::objc_package: return ObjCIvarDecl::Package; 4590 } 4591} 4592 4593/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4594/// in order to create an IvarDecl object for it. 4595Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4596 SourceLocation DeclStart, 4597 DeclPtrTy IntfDecl, 4598 Declarator &D, ExprTy *BitfieldWidth, 4599 tok::ObjCKeywordKind Visibility) { 4600 4601 IdentifierInfo *II = D.getIdentifier(); 4602 Expr *BitWidth = (Expr*)BitfieldWidth; 4603 SourceLocation Loc = DeclStart; 4604 if (II) Loc = D.getIdentifierLoc(); 4605 4606 // FIXME: Unnamed fields can be handled in various different ways, for 4607 // example, unnamed unions inject all members into the struct namespace! 4608 4609 QualType T = GetTypeForDeclarator(D, S); 4610 4611 if (BitWidth) { 4612 // 6.7.2.1p3, 6.7.2.1p4 4613 if (VerifyBitField(Loc, II, T, BitWidth)) { 4614 D.setInvalidType(); 4615 DeleteExpr(BitWidth); 4616 BitWidth = 0; 4617 } 4618 } else { 4619 // Not a bitfield. 4620 4621 // validate II. 4622 4623 } 4624 4625 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4626 // than a variably modified type. 4627 if (T->isVariablyModifiedType()) { 4628 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4629 D.setInvalidType(); 4630 } 4631 4632 // Get the visibility (access control) for this ivar. 4633 ObjCIvarDecl::AccessControl ac = 4634 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4635 : ObjCIvarDecl::None; 4636 // Must set ivar's DeclContext to its enclosing interface. 4637 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4638 DeclContext *EnclosingContext; 4639 if (ObjCImplementationDecl *IMPDecl = 4640 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4641 // Case of ivar declared in an implementation. Context is that of its class. 4642 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4643 assert(IDecl && "No class- ActOnIvar"); 4644 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4645 } 4646 else 4647 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4648 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4649 4650 // Construct the decl. 4651 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4652 EnclosingContext, Loc, II, T,ac, 4653 (Expr *)BitfieldWidth); 4654 4655 if (II) { 4656 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4657 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4658 && !isa<TagDecl>(PrevDecl)) { 4659 Diag(Loc, diag::err_duplicate_member) << II; 4660 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4661 NewID->setInvalidDecl(); 4662 } 4663 } 4664 4665 // Process attributes attached to the ivar. 4666 ProcessDeclAttributes(S, NewID, D); 4667 4668 if (D.isInvalidType()) 4669 NewID->setInvalidDecl(); 4670 4671 if (II) { 4672 // FIXME: When interfaces are DeclContexts, we'll need to add 4673 // these to the interface. 4674 S->AddDecl(DeclPtrTy::make(NewID)); 4675 IdResolver.AddDecl(NewID); 4676 } 4677 4678 return DeclPtrTy::make(NewID); 4679} 4680 4681void Sema::ActOnFields(Scope* S, 4682 SourceLocation RecLoc, DeclPtrTy RecDecl, 4683 DeclPtrTy *Fields, unsigned NumFields, 4684 SourceLocation LBrac, SourceLocation RBrac, 4685 AttributeList *Attr) { 4686 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4687 assert(EnclosingDecl && "missing record or interface decl"); 4688 4689 // If the decl this is being inserted into is invalid, then it may be a 4690 // redeclaration or some other bogus case. Don't try to add fields to it. 4691 if (EnclosingDecl->isInvalidDecl()) { 4692 // FIXME: Deallocate fields? 4693 return; 4694 } 4695 4696 4697 // Verify that all the fields are okay. 4698 unsigned NumNamedMembers = 0; 4699 llvm::SmallVector<FieldDecl*, 32> RecFields; 4700 4701 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4702 for (unsigned i = 0; i != NumFields; ++i) { 4703 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4704 4705 // Get the type for the field. 4706 Type *FDTy = FD->getType().getTypePtr(); 4707 4708 if (!FD->isAnonymousStructOrUnion()) { 4709 // Remember all fields written by the user. 4710 RecFields.push_back(FD); 4711 } 4712 4713 // If the field is already invalid for some reason, don't emit more 4714 // diagnostics about it. 4715 if (FD->isInvalidDecl()) 4716 continue; 4717 4718 // C99 6.7.2.1p2: 4719 // A structure or union shall not contain a member with 4720 // incomplete or function type (hence, a structure shall not 4721 // contain an instance of itself, but may contain a pointer to 4722 // an instance of itself), except that the last member of a 4723 // structure with more than one named member may have incomplete 4724 // array type; such a structure (and any union containing, 4725 // possibly recursively, a member that is such a structure) 4726 // shall not be a member of a structure or an element of an 4727 // array. 4728 if (FDTy->isFunctionType()) { 4729 // Field declared as a function. 4730 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4731 << FD->getDeclName(); 4732 FD->setInvalidDecl(); 4733 EnclosingDecl->setInvalidDecl(); 4734 continue; 4735 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4736 Record && Record->isStruct()) { 4737 // Flexible array member. 4738 if (NumNamedMembers < 1) { 4739 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4740 << FD->getDeclName(); 4741 FD->setInvalidDecl(); 4742 EnclosingDecl->setInvalidDecl(); 4743 continue; 4744 } 4745 // Okay, we have a legal flexible array member at the end of the struct. 4746 if (Record) 4747 Record->setHasFlexibleArrayMember(true); 4748 } else if (!FDTy->isDependentType() && 4749 RequireCompleteType(FD->getLocation(), FD->getType(), 4750 diag::err_field_incomplete)) { 4751 // Incomplete type 4752 FD->setInvalidDecl(); 4753 EnclosingDecl->setInvalidDecl(); 4754 continue; 4755 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4756 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4757 // If this is a member of a union, then entire union becomes "flexible". 4758 if (Record && Record->isUnion()) { 4759 Record->setHasFlexibleArrayMember(true); 4760 } else { 4761 // If this is a struct/class and this is not the last element, reject 4762 // it. Note that GCC supports variable sized arrays in the middle of 4763 // structures. 4764 if (i != NumFields-1) 4765 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4766 << FD->getDeclName() << FD->getType(); 4767 else { 4768 // We support flexible arrays at the end of structs in 4769 // other structs as an extension. 4770 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4771 << FD->getDeclName(); 4772 if (Record) 4773 Record->setHasFlexibleArrayMember(true); 4774 } 4775 } 4776 } 4777 if (Record && FDTTy->getDecl()->hasObjectMember()) 4778 Record->setHasObjectMember(true); 4779 } else if (FDTy->isObjCInterfaceType()) { 4780 /// A field cannot be an Objective-c object 4781 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4782 FD->setInvalidDecl(); 4783 EnclosingDecl->setInvalidDecl(); 4784 continue; 4785 } 4786 else if (getLangOptions().ObjC1 && 4787 getLangOptions().getGCMode() != LangOptions::NonGC && 4788 Record && 4789 (FD->getType()->isObjCObjectPointerType() || 4790 FD->getType().isObjCGCStrong())) 4791 Record->setHasObjectMember(true); 4792 // Keep track of the number of named members. 4793 if (FD->getIdentifier()) 4794 ++NumNamedMembers; 4795 } 4796 4797 // Okay, we successfully defined 'Record'. 4798 if (Record) { 4799 Record->completeDefinition(Context); 4800 } else { 4801 ObjCIvarDecl **ClsFields = 4802 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4803 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4804 ID->setIVarList(ClsFields, RecFields.size(), Context); 4805 ID->setLocEnd(RBrac); 4806 // Add ivar's to class's DeclContext. 4807 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4808 ClsFields[i]->setLexicalDeclContext(ID); 4809 ID->addDecl(ClsFields[i]); 4810 } 4811 // Must enforce the rule that ivars in the base classes may not be 4812 // duplicates. 4813 if (ID->getSuperClass()) { 4814 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4815 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4816 ObjCIvarDecl* Ivar = (*IVI); 4817 4818 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4819 ObjCIvarDecl* prevIvar = 4820 ID->getSuperClass()->lookupInstanceVariable(II); 4821 if (prevIvar) { 4822 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4823 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4824 } 4825 } 4826 } 4827 } 4828 } else if (ObjCImplementationDecl *IMPDecl = 4829 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4830 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4831 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4832 // Ivar declared in @implementation never belongs to the implementation. 4833 // Only it is in implementation's lexical context. 4834 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4835 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4836 } 4837 } 4838 4839 if (Attr) 4840 ProcessDeclAttributeList(S, Record, Attr); 4841} 4842 4843EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4844 EnumConstantDecl *LastEnumConst, 4845 SourceLocation IdLoc, 4846 IdentifierInfo *Id, 4847 ExprArg val) { 4848 Expr *Val = (Expr *)val.get(); 4849 4850 llvm::APSInt EnumVal(32); 4851 QualType EltTy; 4852 if (Val && !Val->isTypeDependent()) { 4853 // Make sure to promote the operand type to int. 4854 UsualUnaryConversions(Val); 4855 if (Val != val.get()) { 4856 val.release(); 4857 val = Val; 4858 } 4859 4860 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4861 SourceLocation ExpLoc; 4862 if (!Val->isValueDependent() && 4863 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4864 Val = 0; 4865 } else { 4866 EltTy = Val->getType(); 4867 } 4868 } 4869 4870 if (!Val) { 4871 if (LastEnumConst) { 4872 // Assign the last value + 1. 4873 EnumVal = LastEnumConst->getInitVal(); 4874 ++EnumVal; 4875 4876 // Check for overflow on increment. 4877 if (EnumVal < LastEnumConst->getInitVal()) 4878 Diag(IdLoc, diag::warn_enum_value_overflow); 4879 4880 EltTy = LastEnumConst->getType(); 4881 } else { 4882 // First value, set to zero. 4883 EltTy = Context.IntTy; 4884 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4885 } 4886 } 4887 4888 val.release(); 4889 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4890 Val, EnumVal); 4891} 4892 4893 4894Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4895 DeclPtrTy lastEnumConst, 4896 SourceLocation IdLoc, 4897 IdentifierInfo *Id, 4898 SourceLocation EqualLoc, ExprTy *val) { 4899 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4900 EnumConstantDecl *LastEnumConst = 4901 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4902 Expr *Val = static_cast<Expr*>(val); 4903 4904 // The scope passed in may not be a decl scope. Zip up the scope tree until 4905 // we find one that is. 4906 S = getNonFieldDeclScope(S); 4907 4908 // Verify that there isn't already something declared with this name in this 4909 // scope. 4910 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4911 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4912 // Maybe we will complain about the shadowed template parameter. 4913 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4914 // Just pretend that we didn't see the previous declaration. 4915 PrevDecl = 0; 4916 } 4917 4918 if (PrevDecl) { 4919 // When in C++, we may get a TagDecl with the same name; in this case the 4920 // enum constant will 'hide' the tag. 4921 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4922 "Received TagDecl when not in C++!"); 4923 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4924 if (isa<EnumConstantDecl>(PrevDecl)) 4925 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4926 else 4927 Diag(IdLoc, diag::err_redefinition) << Id; 4928 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4929 if (Val) Val->Destroy(Context); 4930 return DeclPtrTy(); 4931 } 4932 } 4933 4934 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4935 IdLoc, Id, Owned(Val)); 4936 4937 // Register this decl in the current scope stack. 4938 if (New) 4939 PushOnScopeChains(New, S); 4940 4941 return DeclPtrTy::make(New); 4942} 4943 4944void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4945 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4946 DeclPtrTy *Elements, unsigned NumElements) { 4947 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4948 QualType EnumType = Context.getTypeDeclType(Enum); 4949 4950 // TODO: If the result value doesn't fit in an int, it must be a long or long 4951 // long value. ISO C does not support this, but GCC does as an extension, 4952 // emit a warning. 4953 unsigned IntWidth = Context.Target.getIntWidth(); 4954 4955 // Verify that all the values are okay, compute the size of the values, and 4956 // reverse the list. 4957 unsigned NumNegativeBits = 0; 4958 unsigned NumPositiveBits = 0; 4959 4960 // Keep track of whether all elements have type int. 4961 bool AllElementsInt = true; 4962 4963 for (unsigned i = 0; i != NumElements; ++i) { 4964 EnumConstantDecl *ECD = 4965 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4966 if (!ECD) continue; // Already issued a diagnostic. 4967 4968 // If the enum value doesn't fit in an int, emit an extension warning. 4969 const llvm::APSInt &InitVal = ECD->getInitVal(); 4970 assert(InitVal.getBitWidth() >= IntWidth && 4971 "Should have promoted value to int"); 4972 if (InitVal.getBitWidth() > IntWidth) { 4973 llvm::APSInt V(InitVal); 4974 V.trunc(IntWidth); 4975 V.extend(InitVal.getBitWidth()); 4976 if (V != InitVal) 4977 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4978 << InitVal.toString(10); 4979 } 4980 4981 // Keep track of the size of positive and negative values. 4982 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4983 NumPositiveBits = std::max(NumPositiveBits, 4984 (unsigned)InitVal.getActiveBits()); 4985 else 4986 NumNegativeBits = std::max(NumNegativeBits, 4987 (unsigned)InitVal.getMinSignedBits()); 4988 4989 // Keep track of whether every enum element has type int (very commmon). 4990 if (AllElementsInt) 4991 AllElementsInt = ECD->getType() == Context.IntTy; 4992 } 4993 4994 // Figure out the type that should be used for this enum. 4995 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4996 QualType BestType; 4997 unsigned BestWidth; 4998 4999 if (NumNegativeBits) { 5000 // If there is a negative value, figure out the smallest integer type (of 5001 // int/long/longlong) that fits. 5002 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5003 BestType = Context.IntTy; 5004 BestWidth = IntWidth; 5005 } else { 5006 BestWidth = Context.Target.getLongWidth(); 5007 5008 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5009 BestType = Context.LongTy; 5010 else { 5011 BestWidth = Context.Target.getLongLongWidth(); 5012 5013 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5014 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5015 BestType = Context.LongLongTy; 5016 } 5017 } 5018 } else { 5019 // If there is no negative value, figure out which of uint, ulong, ulonglong 5020 // fits. 5021 if (NumPositiveBits <= IntWidth) { 5022 BestType = Context.UnsignedIntTy; 5023 BestWidth = IntWidth; 5024 } else if (NumPositiveBits <= 5025 (BestWidth = Context.Target.getLongWidth())) { 5026 BestType = Context.UnsignedLongTy; 5027 } else { 5028 BestWidth = Context.Target.getLongLongWidth(); 5029 assert(NumPositiveBits <= BestWidth && 5030 "How could an initializer get larger than ULL?"); 5031 BestType = Context.UnsignedLongLongTy; 5032 } 5033 } 5034 5035 // Loop over all of the enumerator constants, changing their types to match 5036 // the type of the enum if needed. 5037 for (unsigned i = 0; i != NumElements; ++i) { 5038 EnumConstantDecl *ECD = 5039 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5040 if (!ECD) continue; // Already issued a diagnostic. 5041 5042 // Standard C says the enumerators have int type, but we allow, as an 5043 // extension, the enumerators to be larger than int size. If each 5044 // enumerator value fits in an int, type it as an int, otherwise type it the 5045 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5046 // that X has type 'int', not 'unsigned'. 5047 if (ECD->getType() == Context.IntTy) { 5048 // Make sure the init value is signed. 5049 llvm::APSInt IV = ECD->getInitVal(); 5050 IV.setIsSigned(true); 5051 ECD->setInitVal(IV); 5052 5053 if (getLangOptions().CPlusPlus) 5054 // C++ [dcl.enum]p4: Following the closing brace of an 5055 // enum-specifier, each enumerator has the type of its 5056 // enumeration. 5057 ECD->setType(EnumType); 5058 continue; // Already int type. 5059 } 5060 5061 // Determine whether the value fits into an int. 5062 llvm::APSInt InitVal = ECD->getInitVal(); 5063 bool FitsInInt; 5064 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5065 FitsInInt = InitVal.getActiveBits() < IntWidth; 5066 else 5067 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5068 5069 // If it fits into an integer type, force it. Otherwise force it to match 5070 // the enum decl type. 5071 QualType NewTy; 5072 unsigned NewWidth; 5073 bool NewSign; 5074 if (FitsInInt) { 5075 NewTy = Context.IntTy; 5076 NewWidth = IntWidth; 5077 NewSign = true; 5078 } else if (ECD->getType() == BestType) { 5079 // Already the right type! 5080 if (getLangOptions().CPlusPlus) 5081 // C++ [dcl.enum]p4: Following the closing brace of an 5082 // enum-specifier, each enumerator has the type of its 5083 // enumeration. 5084 ECD->setType(EnumType); 5085 continue; 5086 } else { 5087 NewTy = BestType; 5088 NewWidth = BestWidth; 5089 NewSign = BestType->isSignedIntegerType(); 5090 } 5091 5092 // Adjust the APSInt value. 5093 InitVal.extOrTrunc(NewWidth); 5094 InitVal.setIsSigned(NewSign); 5095 ECD->setInitVal(InitVal); 5096 5097 // Adjust the Expr initializer and type. 5098 if (ECD->getInitExpr()) 5099 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 5100 /*isLvalue=*/false)); 5101 if (getLangOptions().CPlusPlus) 5102 // C++ [dcl.enum]p4: Following the closing brace of an 5103 // enum-specifier, each enumerator has the type of its 5104 // enumeration. 5105 ECD->setType(EnumType); 5106 else 5107 ECD->setType(NewTy); 5108 } 5109 5110 Enum->completeDefinition(Context, BestType); 5111} 5112 5113Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5114 ExprArg expr) { 5115 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5116 5117 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5118 Loc, AsmString); 5119 CurContext->addDecl(New); 5120 return DeclPtrTy::make(New); 5121} 5122 5123void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5124 SourceLocation PragmaLoc, 5125 SourceLocation NameLoc) { 5126 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5127 5128 // FIXME: This implementation is an ugly hack! 5129 if (PrevDecl) { 5130 PrevDecl->addAttr(::new (Context) WeakAttr()); 5131 return; 5132 } 5133 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 5134 return; 5135} 5136 5137void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5138 IdentifierInfo* AliasName, 5139 SourceLocation PragmaLoc, 5140 SourceLocation NameLoc, 5141 SourceLocation AliasNameLoc) { 5142 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5143 5144 // FIXME: This implementation is an ugly hack! 5145 if (PrevDecl) { 5146 PrevDecl->addAttr(::new (Context) AliasAttr(AliasName->getName())); 5147 PrevDecl->addAttr(::new (Context) WeakAttr()); 5148 return; 5149 } 5150 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 5151 return; 5152} 5153