SemaDecl.cpp revision 13591ed054d1b2d6d392151ba05cbc883e640648
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 (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1088 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1089 if (FD->hasAttr<NoReturnAttr>()) { 1090 NoReturnEdge = true; 1091 HasFakeEdge = true; 1092 } 1093 } 1094 } 1095 } 1096 // FIXME: Add noreturn message sends. 1097 if (NoReturnEdge == false) 1098 HasPlainEdge = true; 1099 } 1100 if (!HasPlainEdge) 1101 return NeverFallThrough; 1102 if (HasFakeEdge || HasLiveReturn) 1103 return MaybeFallThrough; 1104 // This says AlwaysFallThrough for calls to functions that are not marked 1105 // noreturn, that don't return. If people would like this warning to be more 1106 // accurate, such functions should be marked as noreturn. 1107 return AlwaysFallThrough; 1108} 1109 1110/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1111/// function that should return a value. Check that we don't fall off the end 1112/// of a noreturn function. We assume that functions not marked noreturn will 1113/// return. 1114void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1115 // FIXME: Would be nice if we had a better way to control cascading errors, 1116 // but for now, avoid them. The problem is that when Parse sees: 1117 // int foo() { return a; } 1118 // The return is eaten and the Sema code sees just: 1119 // int foo() { } 1120 // which this code would then warn about. 1121 if (getDiagnostics().hasErrorOccurred()) 1122 return; 1123 bool ReturnsVoid = false; 1124 bool HasNoReturn = false; 1125 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1126 if (FD->getResultType()->isVoidType()) 1127 ReturnsVoid = true; 1128 if (FD->hasAttr<NoReturnAttr>()) 1129 HasNoReturn = true; 1130 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1131 if (MD->getResultType()->isVoidType()) 1132 ReturnsVoid = true; 1133 if (MD->hasAttr<NoReturnAttr>()) 1134 HasNoReturn = true; 1135 } 1136 1137 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1138 == Diagnostic::Ignored || ReturnsVoid) 1139 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1140 == Diagnostic::Ignored || !HasNoReturn)) 1141 return; 1142 // FIXME: Funtion try block 1143 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1144 switch (CheckFallThrough(Body)) { 1145 case MaybeFallThrough: 1146 if (HasNoReturn) 1147 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1148 else if (!ReturnsVoid) 1149 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1150 break; 1151 case AlwaysFallThrough: 1152 if (HasNoReturn) 1153 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1154 else if (!ReturnsVoid) 1155 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1156 break; 1157 case NeverFallThrough: 1158 break; 1159 } 1160 } 1161} 1162 1163/// CheckParmsForFunctionDef - Check that the parameters of the given 1164/// function are appropriate for the definition of a function. This 1165/// takes care of any checks that cannot be performed on the 1166/// declaration itself, e.g., that the types of each of the function 1167/// parameters are complete. 1168bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1169 bool HasInvalidParm = false; 1170 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1171 ParmVarDecl *Param = FD->getParamDecl(p); 1172 1173 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1174 // function declarator that is part of a function definition of 1175 // that function shall not have incomplete type. 1176 // 1177 // This is also C++ [dcl.fct]p6. 1178 if (!Param->isInvalidDecl() && 1179 RequireCompleteType(Param->getLocation(), Param->getType(), 1180 diag::err_typecheck_decl_incomplete_type)) { 1181 Param->setInvalidDecl(); 1182 HasInvalidParm = true; 1183 } 1184 1185 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1186 // declaration of each parameter shall include an identifier. 1187 if (Param->getIdentifier() == 0 && 1188 !Param->isImplicit() && 1189 !getLangOptions().CPlusPlus) 1190 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1191 } 1192 1193 return HasInvalidParm; 1194} 1195 1196/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1197/// no declarator (e.g. "struct foo;") is parsed. 1198Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1199 // FIXME: Error on auto/register at file scope 1200 // FIXME: Error on inline/virtual/explicit 1201 // FIXME: Error on invalid restrict 1202 // FIXME: Warn on useless __thread 1203 // FIXME: Warn on useless const/volatile 1204 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1205 // FIXME: Warn on useless attributes 1206 TagDecl *Tag = 0; 1207 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1208 DS.getTypeSpecType() == DeclSpec::TST_struct || 1209 DS.getTypeSpecType() == DeclSpec::TST_union || 1210 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1211 if (!DS.getTypeRep()) // We probably had an error 1212 return DeclPtrTy(); 1213 1214 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1215 } 1216 1217 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1218 if (!Record->getDeclName() && Record->isDefinition() && 1219 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1220 if (getLangOptions().CPlusPlus || 1221 Record->getDeclContext()->isRecord()) 1222 return BuildAnonymousStructOrUnion(S, DS, Record); 1223 1224 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1225 << DS.getSourceRange(); 1226 } 1227 1228 // Microsoft allows unnamed struct/union fields. Don't complain 1229 // about them. 1230 // FIXME: Should we support Microsoft's extensions in this area? 1231 if (Record->getDeclName() && getLangOptions().Microsoft) 1232 return DeclPtrTy::make(Tag); 1233 } 1234 1235 if (!DS.isMissingDeclaratorOk() && 1236 DS.getTypeSpecType() != DeclSpec::TST_error) { 1237 // Warn about typedefs of enums without names, since this is an 1238 // extension in both Microsoft an GNU. 1239 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1240 Tag && isa<EnumDecl>(Tag)) { 1241 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1242 << DS.getSourceRange(); 1243 return DeclPtrTy::make(Tag); 1244 } 1245 1246 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1247 << DS.getSourceRange(); 1248 return DeclPtrTy(); 1249 } 1250 1251 return DeclPtrTy::make(Tag); 1252} 1253 1254/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1255/// anonymous struct or union AnonRecord into the owning context Owner 1256/// and scope S. This routine will be invoked just after we realize 1257/// that an unnamed union or struct is actually an anonymous union or 1258/// struct, e.g., 1259/// 1260/// @code 1261/// union { 1262/// int i; 1263/// float f; 1264/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1265/// // f into the surrounding scope.x 1266/// @endcode 1267/// 1268/// This routine is recursive, injecting the names of nested anonymous 1269/// structs/unions into the owning context and scope as well. 1270bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1271 RecordDecl *AnonRecord) { 1272 bool Invalid = false; 1273 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1274 FEnd = AnonRecord->field_end(); 1275 F != FEnd; ++F) { 1276 if ((*F)->getDeclName()) { 1277 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1278 LookupOrdinaryName, true); 1279 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1280 // C++ [class.union]p2: 1281 // The names of the members of an anonymous union shall be 1282 // distinct from the names of any other entity in the 1283 // scope in which the anonymous union is declared. 1284 unsigned diagKind 1285 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1286 : diag::err_anonymous_struct_member_redecl; 1287 Diag((*F)->getLocation(), diagKind) 1288 << (*F)->getDeclName(); 1289 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1290 Invalid = true; 1291 } else { 1292 // C++ [class.union]p2: 1293 // For the purpose of name lookup, after the anonymous union 1294 // definition, the members of the anonymous union are 1295 // considered to have been defined in the scope in which the 1296 // anonymous union is declared. 1297 Owner->makeDeclVisibleInContext(*F); 1298 S->AddDecl(DeclPtrTy::make(*F)); 1299 IdResolver.AddDecl(*F); 1300 } 1301 } else if (const RecordType *InnerRecordType 1302 = (*F)->getType()->getAsRecordType()) { 1303 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1304 if (InnerRecord->isAnonymousStructOrUnion()) 1305 Invalid = Invalid || 1306 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1307 } 1308 } 1309 1310 return Invalid; 1311} 1312 1313/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1314/// anonymous structure or union. Anonymous unions are a C++ feature 1315/// (C++ [class.union]) and a GNU C extension; anonymous structures 1316/// are a GNU C and GNU C++ extension. 1317Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1318 RecordDecl *Record) { 1319 DeclContext *Owner = Record->getDeclContext(); 1320 1321 // Diagnose whether this anonymous struct/union is an extension. 1322 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1323 Diag(Record->getLocation(), diag::ext_anonymous_union); 1324 else if (!Record->isUnion()) 1325 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1326 1327 // C and C++ require different kinds of checks for anonymous 1328 // structs/unions. 1329 bool Invalid = false; 1330 if (getLangOptions().CPlusPlus) { 1331 const char* PrevSpec = 0; 1332 // C++ [class.union]p3: 1333 // Anonymous unions declared in a named namespace or in the 1334 // global namespace shall be declared static. 1335 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1336 (isa<TranslationUnitDecl>(Owner) || 1337 (isa<NamespaceDecl>(Owner) && 1338 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1339 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1340 Invalid = true; 1341 1342 // Recover by adding 'static'. 1343 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1344 } 1345 // C++ [class.union]p3: 1346 // A storage class is not allowed in a declaration of an 1347 // anonymous union in a class scope. 1348 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1349 isa<RecordDecl>(Owner)) { 1350 Diag(DS.getStorageClassSpecLoc(), 1351 diag::err_anonymous_union_with_storage_spec); 1352 Invalid = true; 1353 1354 // Recover by removing the storage specifier. 1355 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1356 PrevSpec); 1357 } 1358 1359 // C++ [class.union]p2: 1360 // The member-specification of an anonymous union shall only 1361 // define non-static data members. [Note: nested types and 1362 // functions cannot be declared within an anonymous union. ] 1363 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1364 MemEnd = Record->decls_end(); 1365 Mem != MemEnd; ++Mem) { 1366 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1367 // C++ [class.union]p3: 1368 // An anonymous union shall not have private or protected 1369 // members (clause 11). 1370 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1371 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1372 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1373 Invalid = true; 1374 } 1375 } else if ((*Mem)->isImplicit()) { 1376 // Any implicit members are fine. 1377 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1378 // This is a type that showed up in an 1379 // elaborated-type-specifier inside the anonymous struct or 1380 // union, but which actually declares a type outside of the 1381 // anonymous struct or union. It's okay. 1382 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1383 if (!MemRecord->isAnonymousStructOrUnion() && 1384 MemRecord->getDeclName()) { 1385 // This is a nested type declaration. 1386 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1387 << (int)Record->isUnion(); 1388 Invalid = true; 1389 } 1390 } else { 1391 // We have something that isn't a non-static data 1392 // member. Complain about it. 1393 unsigned DK = diag::err_anonymous_record_bad_member; 1394 if (isa<TypeDecl>(*Mem)) 1395 DK = diag::err_anonymous_record_with_type; 1396 else if (isa<FunctionDecl>(*Mem)) 1397 DK = diag::err_anonymous_record_with_function; 1398 else if (isa<VarDecl>(*Mem)) 1399 DK = diag::err_anonymous_record_with_static; 1400 Diag((*Mem)->getLocation(), DK) 1401 << (int)Record->isUnion(); 1402 Invalid = true; 1403 } 1404 } 1405 } 1406 1407 if (!Record->isUnion() && !Owner->isRecord()) { 1408 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1409 << (int)getLangOptions().CPlusPlus; 1410 Invalid = true; 1411 } 1412 1413 // Create a declaration for this anonymous struct/union. 1414 NamedDecl *Anon = 0; 1415 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1416 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1417 /*IdentifierInfo=*/0, 1418 Context.getTypeDeclType(Record), 1419 /*BitWidth=*/0, /*Mutable=*/false, 1420 DS.getSourceRange().getBegin()); 1421 Anon->setAccess(AS_public); 1422 if (getLangOptions().CPlusPlus) 1423 FieldCollector->Add(cast<FieldDecl>(Anon)); 1424 } else { 1425 VarDecl::StorageClass SC; 1426 switch (DS.getStorageClassSpec()) { 1427 default: assert(0 && "Unknown storage class!"); 1428 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1429 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1430 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1431 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1432 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1433 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1434 case DeclSpec::SCS_mutable: 1435 // mutable can only appear on non-static class members, so it's always 1436 // an error here 1437 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1438 Invalid = true; 1439 SC = VarDecl::None; 1440 break; 1441 } 1442 1443 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1444 /*IdentifierInfo=*/0, 1445 Context.getTypeDeclType(Record), 1446 SC, DS.getSourceRange().getBegin()); 1447 } 1448 Anon->setImplicit(); 1449 1450 // Add the anonymous struct/union object to the current 1451 // context. We'll be referencing this object when we refer to one of 1452 // its members. 1453 Owner->addDecl(Anon); 1454 1455 // Inject the members of the anonymous struct/union into the owning 1456 // context and into the identifier resolver chain for name lookup 1457 // purposes. 1458 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1459 Invalid = true; 1460 1461 // Mark this as an anonymous struct/union type. Note that we do not 1462 // do this until after we have already checked and injected the 1463 // members of this anonymous struct/union type, because otherwise 1464 // the members could be injected twice: once by DeclContext when it 1465 // builds its lookup table, and once by 1466 // InjectAnonymousStructOrUnionMembers. 1467 Record->setAnonymousStructOrUnion(true); 1468 1469 if (Invalid) 1470 Anon->setInvalidDecl(); 1471 1472 return DeclPtrTy::make(Anon); 1473} 1474 1475 1476/// GetNameForDeclarator - Determine the full declaration name for the 1477/// given Declarator. 1478DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1479 switch (D.getKind()) { 1480 case Declarator::DK_Abstract: 1481 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1482 return DeclarationName(); 1483 1484 case Declarator::DK_Normal: 1485 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1486 return DeclarationName(D.getIdentifier()); 1487 1488 case Declarator::DK_Constructor: { 1489 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1490 Ty = Context.getCanonicalType(Ty); 1491 return Context.DeclarationNames.getCXXConstructorName(Ty); 1492 } 1493 1494 case Declarator::DK_Destructor: { 1495 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1496 Ty = Context.getCanonicalType(Ty); 1497 return Context.DeclarationNames.getCXXDestructorName(Ty); 1498 } 1499 1500 case Declarator::DK_Conversion: { 1501 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1502 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1503 Ty = Context.getCanonicalType(Ty); 1504 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1505 } 1506 1507 case Declarator::DK_Operator: 1508 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1509 return Context.DeclarationNames.getCXXOperatorName( 1510 D.getOverloadedOperator()); 1511 } 1512 1513 assert(false && "Unknown name kind"); 1514 return DeclarationName(); 1515} 1516 1517/// isNearlyMatchingFunction - Determine whether the C++ functions 1518/// Declaration and Definition are "nearly" matching. This heuristic 1519/// is used to improve diagnostics in the case where an out-of-line 1520/// function definition doesn't match any declaration within 1521/// the class or namespace. 1522static bool isNearlyMatchingFunction(ASTContext &Context, 1523 FunctionDecl *Declaration, 1524 FunctionDecl *Definition) { 1525 if (Declaration->param_size() != Definition->param_size()) 1526 return false; 1527 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1528 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1529 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1530 1531 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1532 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1533 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1534 return false; 1535 } 1536 1537 return true; 1538} 1539 1540Sema::DeclPtrTy 1541Sema::HandleDeclarator(Scope *S, Declarator &D, 1542 MultiTemplateParamsArg TemplateParamLists, 1543 bool IsFunctionDefinition) { 1544 DeclarationName Name = GetNameForDeclarator(D); 1545 1546 // All of these full declarators require an identifier. If it doesn't have 1547 // one, the ParsedFreeStandingDeclSpec action should be used. 1548 if (!Name) { 1549 if (!D.isInvalidType()) // Reject this if we think it is valid. 1550 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1551 diag::err_declarator_need_ident) 1552 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1553 return DeclPtrTy(); 1554 } 1555 1556 // The scope passed in may not be a decl scope. Zip up the scope tree until 1557 // we find one that is. 1558 while ((S->getFlags() & Scope::DeclScope) == 0 || 1559 (S->getFlags() & Scope::TemplateParamScope) != 0) 1560 S = S->getParent(); 1561 1562 DeclContext *DC; 1563 NamedDecl *PrevDecl; 1564 NamedDecl *New; 1565 1566 QualType R = GetTypeForDeclarator(D, S); 1567 1568 // See if this is a redefinition of a variable in the same scope. 1569 if (D.getCXXScopeSpec().isInvalid()) { 1570 DC = CurContext; 1571 PrevDecl = 0; 1572 D.setInvalidType(); 1573 } else if (!D.getCXXScopeSpec().isSet()) { 1574 LookupNameKind NameKind = LookupOrdinaryName; 1575 1576 // If the declaration we're planning to build will be a function 1577 // or object with linkage, then look for another declaration with 1578 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1579 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1580 /* Do nothing*/; 1581 else if (R->isFunctionType()) { 1582 if (CurContext->isFunctionOrMethod() || 1583 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1584 NameKind = LookupRedeclarationWithLinkage; 1585 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1586 NameKind = LookupRedeclarationWithLinkage; 1587 else if (CurContext->getLookupContext()->isTranslationUnit() && 1588 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1589 NameKind = LookupRedeclarationWithLinkage; 1590 1591 DC = CurContext; 1592 PrevDecl = LookupName(S, Name, NameKind, true, 1593 NameKind == LookupRedeclarationWithLinkage, 1594 D.getIdentifierLoc()); 1595 } else { // Something like "int foo::x;" 1596 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1597 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1598 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1599 1600 // C++ 7.3.1.2p2: 1601 // Members (including explicit specializations of templates) of a named 1602 // namespace can also be defined outside that namespace by explicit 1603 // qualification of the name being defined, provided that the entity being 1604 // defined was already declared in the namespace and the definition appears 1605 // after the point of declaration in a namespace that encloses the 1606 // declarations namespace. 1607 // 1608 // Note that we only check the context at this point. We don't yet 1609 // have enough information to make sure that PrevDecl is actually 1610 // the declaration we want to match. For example, given: 1611 // 1612 // class X { 1613 // void f(); 1614 // void f(float); 1615 // }; 1616 // 1617 // void X::f(int) { } // ill-formed 1618 // 1619 // In this case, PrevDecl will point to the overload set 1620 // containing the two f's declared in X, but neither of them 1621 // matches. 1622 1623 // First check whether we named the global scope. 1624 if (isa<TranslationUnitDecl>(DC)) { 1625 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1626 << Name << D.getCXXScopeSpec().getRange(); 1627 } else if (!CurContext->Encloses(DC)) { 1628 // The qualifying scope doesn't enclose the original declaration. 1629 // Emit diagnostic based on current scope. 1630 SourceLocation L = D.getIdentifierLoc(); 1631 SourceRange R = D.getCXXScopeSpec().getRange(); 1632 if (isa<FunctionDecl>(CurContext)) 1633 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1634 else 1635 Diag(L, diag::err_invalid_declarator_scope) 1636 << Name << cast<NamedDecl>(DC) << R; 1637 D.setInvalidType(); 1638 } 1639 } 1640 1641 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1642 // Maybe we will complain about the shadowed template parameter. 1643 if (!D.isInvalidType()) 1644 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1645 D.setInvalidType(); 1646 1647 // Just pretend that we didn't see the previous declaration. 1648 PrevDecl = 0; 1649 } 1650 1651 // In C++, the previous declaration we find might be a tag type 1652 // (class or enum). In this case, the new declaration will hide the 1653 // tag type. Note that this does does not apply if we're declaring a 1654 // typedef (C++ [dcl.typedef]p4). 1655 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1656 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1657 PrevDecl = 0; 1658 1659 bool Redeclaration = false; 1660 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1661 if (TemplateParamLists.size()) { 1662 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1663 return DeclPtrTy(); 1664 } 1665 1666 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1667 } else if (R->isFunctionType()) { 1668 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1669 move(TemplateParamLists), 1670 IsFunctionDefinition, Redeclaration); 1671 } else { 1672 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1673 move(TemplateParamLists), 1674 Redeclaration); 1675 } 1676 1677 if (New == 0) 1678 return DeclPtrTy(); 1679 1680 // If this has an identifier and is not an invalid redeclaration, 1681 // add it to the scope stack. 1682 if (Name && !(Redeclaration && New->isInvalidDecl())) 1683 PushOnScopeChains(New, S); 1684 1685 return DeclPtrTy::make(New); 1686} 1687 1688/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1689/// types into constant array types in certain situations which would otherwise 1690/// be errors (for GCC compatibility). 1691static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1692 ASTContext &Context, 1693 bool &SizeIsNegative) { 1694 // This method tries to turn a variable array into a constant 1695 // array even when the size isn't an ICE. This is necessary 1696 // for compatibility with code that depends on gcc's buggy 1697 // constant expression folding, like struct {char x[(int)(char*)2];} 1698 SizeIsNegative = false; 1699 1700 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1701 QualType Pointee = PTy->getPointeeType(); 1702 QualType FixedType = 1703 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1704 if (FixedType.isNull()) return FixedType; 1705 FixedType = Context.getPointerType(FixedType); 1706 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1707 return FixedType; 1708 } 1709 1710 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1711 if (!VLATy) 1712 return QualType(); 1713 // FIXME: We should probably handle this case 1714 if (VLATy->getElementType()->isVariablyModifiedType()) 1715 return QualType(); 1716 1717 Expr::EvalResult EvalResult; 1718 if (!VLATy->getSizeExpr() || 1719 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1720 !EvalResult.Val.isInt()) 1721 return QualType(); 1722 1723 llvm::APSInt &Res = EvalResult.Val.getInt(); 1724 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1725 Expr* ArySizeExpr = VLATy->getSizeExpr(); 1726 // FIXME: here we could "steal" (how?) ArySizeExpr from the VLA, 1727 // so as to transfer ownership to the ConstantArrayWithExpr. 1728 // Alternatively, we could "clone" it (how?). 1729 // Since we don't know how to do things above, we just use the 1730 // very same Expr*. 1731 return Context.getConstantArrayWithExprType(VLATy->getElementType(), 1732 Res, ArySizeExpr, 1733 ArrayType::Normal, 0, 1734 VLATy->getBracketsRange()); 1735 } 1736 1737 SizeIsNegative = true; 1738 return QualType(); 1739} 1740 1741/// \brief Register the given locally-scoped external C declaration so 1742/// that it can be found later for redeclarations 1743void 1744Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1745 Scope *S) { 1746 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1747 "Decl is not a locally-scoped decl!"); 1748 // Note that we have a locally-scoped external with this name. 1749 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1750 1751 if (!PrevDecl) 1752 return; 1753 1754 // If there was a previous declaration of this variable, it may be 1755 // in our identifier chain. Update the identifier chain with the new 1756 // declaration. 1757 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1758 // The previous declaration was found on the identifer resolver 1759 // chain, so remove it from its scope. 1760 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1761 S = S->getParent(); 1762 1763 if (S) 1764 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1765 } 1766} 1767 1768/// \brief Diagnose function specifiers on a declaration of an identifier that 1769/// does not identify a function. 1770void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1771 // FIXME: We should probably indicate the identifier in question to avoid 1772 // confusion for constructs like "inline int a(), b;" 1773 if (D.getDeclSpec().isInlineSpecified()) 1774 Diag(D.getDeclSpec().getInlineSpecLoc(), 1775 diag::err_inline_non_function); 1776 1777 if (D.getDeclSpec().isVirtualSpecified()) 1778 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1779 diag::err_virtual_non_function); 1780 1781 if (D.getDeclSpec().isExplicitSpecified()) 1782 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1783 diag::err_explicit_non_function); 1784} 1785 1786NamedDecl* 1787Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1788 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1789 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1790 if (D.getCXXScopeSpec().isSet()) { 1791 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1792 << D.getCXXScopeSpec().getRange(); 1793 D.setInvalidType(); 1794 // Pretend we didn't see the scope specifier. 1795 DC = 0; 1796 } 1797 1798 if (getLangOptions().CPlusPlus) { 1799 // Check that there are no default arguments (C++ only). 1800 CheckExtraCXXDefaultArguments(D); 1801 } 1802 1803 DiagnoseFunctionSpecifiers(D); 1804 1805 if (D.getDeclSpec().isThreadSpecified()) 1806 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1807 1808 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1809 if (!NewTD) return 0; 1810 1811 if (D.isInvalidType()) 1812 NewTD->setInvalidDecl(); 1813 1814 // Handle attributes prior to checking for duplicates in MergeVarDecl 1815 ProcessDeclAttributes(S, NewTD, D); 1816 // Merge the decl with the existing one if appropriate. If the decl is 1817 // in an outer scope, it isn't the same thing. 1818 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1819 Redeclaration = true; 1820 MergeTypeDefDecl(NewTD, PrevDecl); 1821 } 1822 1823 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1824 // then it shall have block scope. 1825 QualType T = NewTD->getUnderlyingType(); 1826 if (T->isVariablyModifiedType()) { 1827 CurFunctionNeedsScopeChecking = true; 1828 1829 if (S->getFnParent() == 0) { 1830 bool SizeIsNegative; 1831 QualType FixedTy = 1832 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1833 if (!FixedTy.isNull()) { 1834 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1835 NewTD->setUnderlyingType(FixedTy); 1836 } else { 1837 if (SizeIsNegative) 1838 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1839 else if (T->isVariableArrayType()) 1840 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1841 else 1842 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1843 NewTD->setInvalidDecl(); 1844 } 1845 } 1846 } 1847 1848 // If this is the C FILE type, notify the AST context. 1849 if (IdentifierInfo *II = NewTD->getIdentifier()) 1850 if (!NewTD->isInvalidDecl() && 1851 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit() && 1852 II->isStr("FILE")) 1853 Context.setFILEDecl(NewTD); 1854 1855 return NewTD; 1856} 1857 1858/// \brief Determines whether the given declaration is an out-of-scope 1859/// previous declaration. 1860/// 1861/// This routine should be invoked when name lookup has found a 1862/// previous declaration (PrevDecl) that is not in the scope where a 1863/// new declaration by the same name is being introduced. If the new 1864/// declaration occurs in a local scope, previous declarations with 1865/// linkage may still be considered previous declarations (C99 1866/// 6.2.2p4-5, C++ [basic.link]p6). 1867/// 1868/// \param PrevDecl the previous declaration found by name 1869/// lookup 1870/// 1871/// \param DC the context in which the new declaration is being 1872/// declared. 1873/// 1874/// \returns true if PrevDecl is an out-of-scope previous declaration 1875/// for a new delcaration with the same name. 1876static bool 1877isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1878 ASTContext &Context) { 1879 if (!PrevDecl) 1880 return 0; 1881 1882 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1883 // case we need to check each of the overloaded functions. 1884 if (!PrevDecl->hasLinkage()) 1885 return false; 1886 1887 if (Context.getLangOptions().CPlusPlus) { 1888 // C++ [basic.link]p6: 1889 // If there is a visible declaration of an entity with linkage 1890 // having the same name and type, ignoring entities declared 1891 // outside the innermost enclosing namespace scope, the block 1892 // scope declaration declares that same entity and receives the 1893 // linkage of the previous declaration. 1894 DeclContext *OuterContext = DC->getLookupContext(); 1895 if (!OuterContext->isFunctionOrMethod()) 1896 // This rule only applies to block-scope declarations. 1897 return false; 1898 else { 1899 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1900 if (PrevOuterContext->isRecord()) 1901 // We found a member function: ignore it. 1902 return false; 1903 else { 1904 // Find the innermost enclosing namespace for the new and 1905 // previous declarations. 1906 while (!OuterContext->isFileContext()) 1907 OuterContext = OuterContext->getParent(); 1908 while (!PrevOuterContext->isFileContext()) 1909 PrevOuterContext = PrevOuterContext->getParent(); 1910 1911 // The previous declaration is in a different namespace, so it 1912 // isn't the same function. 1913 if (OuterContext->getPrimaryContext() != 1914 PrevOuterContext->getPrimaryContext()) 1915 return false; 1916 } 1917 } 1918 } 1919 1920 return true; 1921} 1922 1923NamedDecl* 1924Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1925 QualType R,NamedDecl* PrevDecl, 1926 MultiTemplateParamsArg TemplateParamLists, 1927 bool &Redeclaration) { 1928 DeclarationName Name = GetNameForDeclarator(D); 1929 1930 // Check that there are no default arguments (C++ only). 1931 if (getLangOptions().CPlusPlus) 1932 CheckExtraCXXDefaultArguments(D); 1933 1934 VarDecl *NewVD; 1935 VarDecl::StorageClass SC; 1936 switch (D.getDeclSpec().getStorageClassSpec()) { 1937 default: assert(0 && "Unknown storage class!"); 1938 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1939 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1940 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1941 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1942 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1943 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1944 case DeclSpec::SCS_mutable: 1945 // mutable can only appear on non-static class members, so it's always 1946 // an error here 1947 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1948 D.setInvalidType(); 1949 SC = VarDecl::None; 1950 break; 1951 } 1952 1953 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1954 if (!II) { 1955 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1956 << Name.getAsString(); 1957 return 0; 1958 } 1959 1960 DiagnoseFunctionSpecifiers(D); 1961 1962 if (!DC->isRecord() && S->getFnParent() == 0) { 1963 // C99 6.9p2: The storage-class specifiers auto and register shall not 1964 // appear in the declaration specifiers in an external declaration. 1965 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1966 1967 // If this is a register variable with an asm label specified, then this 1968 // is a GNU extension. 1969 if (SC == VarDecl::Register && D.getAsmLabel()) 1970 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1971 else 1972 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1973 D.setInvalidType(); 1974 } 1975 } 1976 if (DC->isRecord() && !CurContext->isRecord()) { 1977 // This is an out-of-line definition of a static data member. 1978 if (SC == VarDecl::Static) { 1979 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1980 diag::err_static_out_of_line) 1981 << CodeModificationHint::CreateRemoval( 1982 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1983 } else if (SC == VarDecl::None) 1984 SC = VarDecl::Static; 1985 } 1986 if (SC == VarDecl::Static) { 1987 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 1988 if (RD->isLocalClass()) 1989 Diag(D.getIdentifierLoc(), 1990 diag::err_static_data_member_not_allowed_in_local_class) 1991 << Name << RD->getDeclName(); 1992 } 1993 } 1994 1995 // Check that we can declare a template here. 1996 if (TemplateParamLists.size() && 1997 CheckTemplateDeclScope(S, TemplateParamLists)) 1998 return 0; 1999 2000 // Match up the template parameter lists with the scope specifier, then 2001 // determine whether we have a template or a template specialization. 2002 if (TemplateParameterList *TemplateParams 2003 = MatchTemplateParametersToScopeSpecifier( 2004 D.getDeclSpec().getSourceRange().getBegin(), 2005 D.getCXXScopeSpec(), 2006 (TemplateParameterList**)TemplateParamLists.get(), 2007 TemplateParamLists.size())) { 2008 if (TemplateParams->size() > 0) { 2009 // There is no such thing as a variable template. 2010 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2011 << II 2012 << SourceRange(TemplateParams->getTemplateLoc(), 2013 TemplateParams->getRAngleLoc()); 2014 return 0; 2015 } else { 2016 // There is an extraneous 'template<>' for this variable. Complain 2017 // about it, but allow the declaration of the variable. 2018 Diag(TemplateParams->getTemplateLoc(), 2019 diag::err_template_variable_noparams) 2020 << II 2021 << SourceRange(TemplateParams->getTemplateLoc(), 2022 TemplateParams->getRAngleLoc()); 2023 } 2024 } 2025 2026 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2027 II, R, SC, 2028 // FIXME: Move to DeclGroup... 2029 D.getDeclSpec().getSourceRange().getBegin()); 2030 2031 if (D.isInvalidType()) 2032 NewVD->setInvalidDecl(); 2033 2034 if (D.getDeclSpec().isThreadSpecified()) { 2035 if (NewVD->hasLocalStorage()) 2036 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2037 else if (!Context.Target.isTLSSupported()) 2038 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2039 else 2040 NewVD->setThreadSpecified(true); 2041 } 2042 2043 // Set the lexical context. If the declarator has a C++ scope specifier, the 2044 // lexical context will be different from the semantic context. 2045 NewVD->setLexicalDeclContext(CurContext); 2046 2047 // Handle attributes prior to checking for duplicates in MergeVarDecl 2048 ProcessDeclAttributes(S, NewVD, D); 2049 2050 // Handle GNU asm-label extension (encoded as an attribute). 2051 if (Expr *E = (Expr*) D.getAsmLabel()) { 2052 // The parser guarantees this is a string. 2053 StringLiteral *SE = cast<StringLiteral>(E); 2054 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2055 SE->getByteLength()))); 2056 } 2057 2058 // If name lookup finds a previous declaration that is not in the 2059 // same scope as the new declaration, this may still be an 2060 // acceptable redeclaration. 2061 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2062 !(NewVD->hasLinkage() && 2063 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2064 PrevDecl = 0; 2065 2066 // Merge the decl with the existing one if appropriate. 2067 if (PrevDecl) { 2068 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2069 // The user tried to define a non-static data member 2070 // out-of-line (C++ [dcl.meaning]p1). 2071 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2072 << D.getCXXScopeSpec().getRange(); 2073 PrevDecl = 0; 2074 NewVD->setInvalidDecl(); 2075 } 2076 } else if (D.getCXXScopeSpec().isSet()) { 2077 // No previous declaration in the qualifying scope. 2078 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 2079 << Name << D.getCXXScopeSpec().getRange(); 2080 NewVD->setInvalidDecl(); 2081 } 2082 2083 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2084 2085 // If this is a locally-scoped extern C variable, update the map of 2086 // such variables. 2087 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 2088 !NewVD->isInvalidDecl()) 2089 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2090 2091 return NewVD; 2092} 2093 2094/// \brief Perform semantic checking on a newly-created variable 2095/// declaration. 2096/// 2097/// This routine performs all of the type-checking required for a 2098/// variable declaration once it has been built. It is used both to 2099/// check variables after they have been parsed and their declarators 2100/// have been translated into a declaration, and to check variables 2101/// that have been instantiated from a template. 2102/// 2103/// Sets NewVD->isInvalidDecl() if an error was encountered. 2104void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2105 bool &Redeclaration) { 2106 // If the decl is already known invalid, don't check it. 2107 if (NewVD->isInvalidDecl()) 2108 return; 2109 2110 QualType T = NewVD->getType(); 2111 2112 if (T->isObjCInterfaceType()) { 2113 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2114 return NewVD->setInvalidDecl(); 2115 } 2116 2117 // The variable can not have an abstract class type. 2118 if (RequireNonAbstractType(NewVD->getLocation(), T, 2119 diag::err_abstract_type_in_decl, 2120 AbstractVariableType)) 2121 return NewVD->setInvalidDecl(); 2122 2123 // Emit an error if an address space was applied to decl with local storage. 2124 // This includes arrays of objects with address space qualifiers, but not 2125 // automatic variables that point to other address spaces. 2126 // ISO/IEC TR 18037 S5.1.2 2127 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2128 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2129 return NewVD->setInvalidDecl(); 2130 } 2131 2132 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2133 && !NewVD->hasAttr<BlocksAttr>()) 2134 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2135 2136 bool isVM = T->isVariablyModifiedType(); 2137 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2138 NewVD->hasAttr<BlocksAttr>()) 2139 CurFunctionNeedsScopeChecking = true; 2140 2141 if ((isVM && NewVD->hasLinkage()) || 2142 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2143 bool SizeIsNegative; 2144 QualType FixedTy = 2145 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2146 2147 if (FixedTy.isNull() && T->isVariableArrayType()) { 2148 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2149 // FIXME: This won't give the correct result for 2150 // int a[10][n]; 2151 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2152 2153 if (NewVD->isFileVarDecl()) 2154 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2155 << SizeRange; 2156 else if (NewVD->getStorageClass() == VarDecl::Static) 2157 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2158 << SizeRange; 2159 else 2160 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2161 << SizeRange; 2162 return NewVD->setInvalidDecl(); 2163 } 2164 2165 if (FixedTy.isNull()) { 2166 if (NewVD->isFileVarDecl()) 2167 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2168 else 2169 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2170 return NewVD->setInvalidDecl(); 2171 } 2172 2173 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2174 NewVD->setType(FixedTy); 2175 } 2176 2177 if (!PrevDecl && NewVD->isExternC(Context)) { 2178 // Since we did not find anything by this name and we're declaring 2179 // an extern "C" variable, look for a non-visible extern "C" 2180 // declaration with the same name. 2181 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2182 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2183 if (Pos != LocallyScopedExternalDecls.end()) 2184 PrevDecl = Pos->second; 2185 } 2186 2187 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2188 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2189 << T; 2190 return NewVD->setInvalidDecl(); 2191 } 2192 2193 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2194 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2195 return NewVD->setInvalidDecl(); 2196 } 2197 2198 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2199 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2200 return NewVD->setInvalidDecl(); 2201 } 2202 2203 if (PrevDecl) { 2204 Redeclaration = true; 2205 MergeVarDecl(NewVD, PrevDecl); 2206 } 2207} 2208 2209NamedDecl* 2210Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2211 QualType R, NamedDecl* PrevDecl, 2212 MultiTemplateParamsArg TemplateParamLists, 2213 bool IsFunctionDefinition, bool &Redeclaration) { 2214 assert(R.getTypePtr()->isFunctionType()); 2215 2216 DeclarationName Name = GetNameForDeclarator(D); 2217 FunctionDecl::StorageClass SC = FunctionDecl::None; 2218 switch (D.getDeclSpec().getStorageClassSpec()) { 2219 default: assert(0 && "Unknown storage class!"); 2220 case DeclSpec::SCS_auto: 2221 case DeclSpec::SCS_register: 2222 case DeclSpec::SCS_mutable: 2223 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2224 diag::err_typecheck_sclass_func); 2225 D.setInvalidType(); 2226 break; 2227 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2228 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2229 case DeclSpec::SCS_static: { 2230 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2231 // C99 6.7.1p5: 2232 // The declaration of an identifier for a function that has 2233 // block scope shall have no explicit storage-class specifier 2234 // other than extern 2235 // See also (C++ [dcl.stc]p4). 2236 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2237 diag::err_static_block_func); 2238 SC = FunctionDecl::None; 2239 } else 2240 SC = FunctionDecl::Static; 2241 break; 2242 } 2243 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2244 } 2245 2246 if (D.getDeclSpec().isThreadSpecified()) 2247 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2248 2249 bool isInline = D.getDeclSpec().isInlineSpecified(); 2250 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2251 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2252 2253 // Check that the return type is not an abstract class type. 2254 // For record types, this is done by the AbstractClassUsageDiagnoser once 2255 // the class has been completely parsed. 2256 if (!DC->isRecord() && 2257 RequireNonAbstractType(D.getIdentifierLoc(), 2258 R->getAsFunctionType()->getResultType(), 2259 diag::err_abstract_type_in_decl, 2260 AbstractReturnType)) 2261 D.setInvalidType(); 2262 2263 // Do not allow returning a objc interface by-value. 2264 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2265 Diag(D.getIdentifierLoc(), 2266 diag::err_object_cannot_be_passed_returned_by_value) << 0 2267 << R->getAsFunctionType()->getResultType(); 2268 D.setInvalidType(); 2269 } 2270 2271 // Check that we can declare a template here. 2272 if (TemplateParamLists.size() && 2273 CheckTemplateDeclScope(S, TemplateParamLists)) 2274 return 0; 2275 2276 bool isVirtualOkay = false; 2277 FunctionDecl *NewFD; 2278 if (D.getKind() == Declarator::DK_Constructor) { 2279 // This is a C++ constructor declaration. 2280 assert(DC->isRecord() && 2281 "Constructors can only be declared in a member context"); 2282 2283 R = CheckConstructorDeclarator(D, R, SC); 2284 2285 // Create the new declaration 2286 NewFD = CXXConstructorDecl::Create(Context, 2287 cast<CXXRecordDecl>(DC), 2288 D.getIdentifierLoc(), Name, R, 2289 isExplicit, isInline, 2290 /*isImplicitlyDeclared=*/false); 2291 } else if (D.getKind() == Declarator::DK_Destructor) { 2292 // This is a C++ destructor declaration. 2293 if (DC->isRecord()) { 2294 R = CheckDestructorDeclarator(D, SC); 2295 2296 NewFD = CXXDestructorDecl::Create(Context, 2297 cast<CXXRecordDecl>(DC), 2298 D.getIdentifierLoc(), Name, R, 2299 isInline, 2300 /*isImplicitlyDeclared=*/false); 2301 2302 isVirtualOkay = true; 2303 } else { 2304 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2305 2306 // Create a FunctionDecl to satisfy the function definition parsing 2307 // code path. 2308 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2309 Name, R, SC, isInline, 2310 /*hasPrototype=*/true, 2311 // FIXME: Move to DeclGroup... 2312 D.getDeclSpec().getSourceRange().getBegin()); 2313 D.setInvalidType(); 2314 } 2315 } else if (D.getKind() == Declarator::DK_Conversion) { 2316 if (!DC->isRecord()) { 2317 Diag(D.getIdentifierLoc(), 2318 diag::err_conv_function_not_member); 2319 return 0; 2320 } 2321 2322 CheckConversionDeclarator(D, R, SC); 2323 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2324 D.getIdentifierLoc(), Name, R, 2325 isInline, isExplicit); 2326 2327 isVirtualOkay = true; 2328 } else if (DC->isRecord()) { 2329 // If the of the function is the same as the name of the record, then this 2330 // must be an invalid constructor that has a return type. 2331 // (The parser checks for a return type and makes the declarator a 2332 // constructor if it has no return type). 2333 // must have an invalid constructor that has a return type 2334 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2335 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2336 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2337 << SourceRange(D.getIdentifierLoc()); 2338 return 0; 2339 } 2340 2341 // This is a C++ method declaration. 2342 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2343 D.getIdentifierLoc(), Name, R, 2344 (SC == FunctionDecl::Static), isInline); 2345 2346 isVirtualOkay = (SC != FunctionDecl::Static); 2347 } else { 2348 // Determine whether the function was written with a 2349 // prototype. This true when: 2350 // - we're in C++ (where every function has a prototype), 2351 // - there is a prototype in the declarator, or 2352 // - the type R of the function is some kind of typedef or other reference 2353 // to a type name (which eventually refers to a function type). 2354 bool HasPrototype = 2355 getLangOptions().CPlusPlus || 2356 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2357 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2358 2359 NewFD = FunctionDecl::Create(Context, DC, 2360 D.getIdentifierLoc(), 2361 Name, R, SC, isInline, HasPrototype, 2362 // FIXME: Move to DeclGroup... 2363 D.getDeclSpec().getSourceRange().getBegin()); 2364 } 2365 2366 if (D.isInvalidType()) 2367 NewFD->setInvalidDecl(); 2368 2369 // Set the lexical context. If the declarator has a C++ 2370 // scope specifier, the lexical context will be different 2371 // from the semantic context. 2372 NewFD->setLexicalDeclContext(CurContext); 2373 2374 // Match up the template parameter lists with the scope specifier, then 2375 // determine whether we have a template or a template specialization. 2376 FunctionTemplateDecl *FunctionTemplate = 0; 2377 if (TemplateParameterList *TemplateParams 2378 = MatchTemplateParametersToScopeSpecifier( 2379 D.getDeclSpec().getSourceRange().getBegin(), 2380 D.getCXXScopeSpec(), 2381 (TemplateParameterList**)TemplateParamLists.get(), 2382 TemplateParamLists.size())) { 2383 if (TemplateParams->size() > 0) { 2384 // This is a function template 2385 FunctionTemplate = FunctionTemplateDecl::Create(Context, CurContext, 2386 NewFD->getLocation(), 2387 Name, TemplateParams, 2388 NewFD); 2389 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2390 } else { 2391 // FIXME: Handle function template specializations 2392 } 2393 2394 // FIXME: Free this memory properly. 2395 TemplateParamLists.release(); 2396 } 2397 2398 // C++ [dcl.fct.spec]p5: 2399 // The virtual specifier shall only be used in declarations of 2400 // nonstatic class member functions that appear within a 2401 // member-specification of a class declaration; see 10.3. 2402 // 2403 if (isVirtual && !NewFD->isInvalidDecl()) { 2404 if (!isVirtualOkay) { 2405 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2406 diag::err_virtual_non_function); 2407 } else if (!CurContext->isRecord()) { 2408 // 'virtual' was specified outside of the class. 2409 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2410 << CodeModificationHint::CreateRemoval( 2411 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2412 } else { 2413 // Okay: Add virtual to the method. 2414 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2415 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2416 CurClass->setAggregate(false); 2417 CurClass->setPOD(false); 2418 CurClass->setPolymorphic(true); 2419 CurClass->setHasTrivialConstructor(false); 2420 CurClass->setHasTrivialCopyConstructor(false); 2421 CurClass->setHasTrivialCopyAssignment(false); 2422 } 2423 } 2424 2425 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2426 // Look for virtual methods in base classes that this method might override. 2427 2428 BasePaths Paths; 2429 if (LookupInBases(cast<CXXRecordDecl>(DC), 2430 MemberLookupCriteria(NewMD), Paths)) { 2431 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2432 E = Paths.found_decls_end(); I != E; ++I) { 2433 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2434 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2435 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2436 NewMD->addOverriddenMethod(OldMD); 2437 } 2438 } 2439 } 2440 } 2441 2442 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2443 !CurContext->isRecord()) { 2444 // C++ [class.static]p1: 2445 // A data or function member of a class may be declared static 2446 // in a class definition, in which case it is a static member of 2447 // the class. 2448 2449 // Complain about the 'static' specifier if it's on an out-of-line 2450 // member function definition. 2451 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2452 diag::err_static_out_of_line) 2453 << CodeModificationHint::CreateRemoval( 2454 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2455 } 2456 2457 // Handle GNU asm-label extension (encoded as an attribute). 2458 if (Expr *E = (Expr*) D.getAsmLabel()) { 2459 // The parser guarantees this is a string. 2460 StringLiteral *SE = cast<StringLiteral>(E); 2461 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2462 SE->getByteLength()))); 2463 } 2464 2465 // Copy the parameter declarations from the declarator D to the function 2466 // declaration NewFD, if they are available. First scavenge them into Params. 2467 llvm::SmallVector<ParmVarDecl*, 16> Params; 2468 if (D.getNumTypeObjects() > 0) { 2469 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2470 2471 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2472 // function that takes no arguments, not a function that takes a 2473 // single void argument. 2474 // We let through "const void" here because Sema::GetTypeForDeclarator 2475 // already checks for that case. 2476 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2477 FTI.ArgInfo[0].Param && 2478 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2479 // Empty arg list, don't push any params. 2480 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2481 2482 // In C++, the empty parameter-type-list must be spelled "void"; a 2483 // typedef of void is not permitted. 2484 if (getLangOptions().CPlusPlus && 2485 Param->getType().getUnqualifiedType() != Context.VoidTy) 2486 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2487 // FIXME: Leaks decl? 2488 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2489 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2490 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2491 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2492 Param->setDeclContext(NewFD); 2493 Params.push_back(Param); 2494 } 2495 } 2496 2497 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2498 // When we're declaring a function with a typedef, typeof, etc as in the 2499 // following example, we'll need to synthesize (unnamed) 2500 // parameters for use in the declaration. 2501 // 2502 // @code 2503 // typedef void fn(int); 2504 // fn f; 2505 // @endcode 2506 2507 // Synthesize a parameter for each argument type. 2508 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2509 AE = FT->arg_type_end(); AI != AE; ++AI) { 2510 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2511 SourceLocation(), 0, 2512 *AI, VarDecl::None, 0); 2513 Param->setImplicit(); 2514 Params.push_back(Param); 2515 } 2516 } else { 2517 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2518 "Should not need args for typedef of non-prototype fn"); 2519 } 2520 // Finally, we know we have the right number of parameters, install them. 2521 NewFD->setParams(Context, Params.data(), Params.size()); 2522 2523 // If name lookup finds a previous declaration that is not in the 2524 // same scope as the new declaration, this may still be an 2525 // acceptable redeclaration. 2526 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2527 !(NewFD->hasLinkage() && 2528 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2529 PrevDecl = 0; 2530 2531 // Perform semantic checking on the function declaration. 2532 bool OverloadableAttrRequired = false; // FIXME: HACK! 2533 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2534 /*FIXME:*/OverloadableAttrRequired); 2535 2536 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2537 // An out-of-line member function declaration must also be a 2538 // definition (C++ [dcl.meaning]p1). 2539 if (!IsFunctionDefinition) { 2540 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2541 << D.getCXXScopeSpec().getRange(); 2542 NewFD->setInvalidDecl(); 2543 } else if (!Redeclaration && (!PrevDecl || !isa<UsingDecl>(PrevDecl))) { 2544 // The user tried to provide an out-of-line definition for a 2545 // function that is a member of a class or namespace, but there 2546 // was no such member function declared (C++ [class.mfct]p2, 2547 // C++ [namespace.memdef]p2). For example: 2548 // 2549 // class X { 2550 // void f() const; 2551 // }; 2552 // 2553 // void X::f() { } // ill-formed 2554 // 2555 // Complain about this problem, and attempt to suggest close 2556 // matches (e.g., those that differ only in cv-qualifiers and 2557 // whether the parameter types are references). 2558 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2559 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2560 NewFD->setInvalidDecl(); 2561 2562 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2563 true); 2564 assert(!Prev.isAmbiguous() && 2565 "Cannot have an ambiguity in previous-declaration lookup"); 2566 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2567 Func != FuncEnd; ++Func) { 2568 if (isa<FunctionDecl>(*Func) && 2569 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2570 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2571 } 2572 2573 PrevDecl = 0; 2574 } 2575 } 2576 2577 // Handle attributes. We need to have merged decls when handling attributes 2578 // (for example to check for conflicts, etc). 2579 // FIXME: This needs to happen before we merge declarations. Then, 2580 // let attribute merging cope with attribute conflicts. 2581 ProcessDeclAttributes(S, NewFD, D); 2582 AddKnownFunctionAttributes(NewFD); 2583 2584 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2585 // If a function name is overloadable in C, then every function 2586 // with that name must be marked "overloadable". 2587 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2588 << Redeclaration << NewFD; 2589 if (PrevDecl) 2590 Diag(PrevDecl->getLocation(), 2591 diag::note_attribute_overloadable_prev_overload); 2592 NewFD->addAttr(::new (Context) OverloadableAttr()); 2593 } 2594 2595 // If this is a locally-scoped extern C function, update the 2596 // map of such names. 2597 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2598 && !NewFD->isInvalidDecl()) 2599 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2600 2601 // Set this FunctionDecl's range up to the right paren. 2602 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2603 2604 if (FunctionTemplate && NewFD->isInvalidDecl()) 2605 FunctionTemplate->setInvalidDecl(); 2606 2607 if (FunctionTemplate) 2608 return FunctionTemplate; 2609 2610 return NewFD; 2611} 2612 2613/// \brief Perform semantic checking of a new function declaration. 2614/// 2615/// Performs semantic analysis of the new function declaration 2616/// NewFD. This routine performs all semantic checking that does not 2617/// require the actual declarator involved in the declaration, and is 2618/// used both for the declaration of functions as they are parsed 2619/// (called via ActOnDeclarator) and for the declaration of functions 2620/// that have been instantiated via C++ template instantiation (called 2621/// via InstantiateDecl). 2622/// 2623/// This sets NewFD->isInvalidDecl() to true if there was an error. 2624void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2625 bool &Redeclaration, 2626 bool &OverloadableAttrRequired) { 2627 // If NewFD is already known erroneous, don't do any of this checking. 2628 if (NewFD->isInvalidDecl()) 2629 return; 2630 2631 if (NewFD->getResultType()->isVariablyModifiedType()) { 2632 // Functions returning a variably modified type violate C99 6.7.5.2p2 2633 // because all functions have linkage. 2634 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2635 return NewFD->setInvalidDecl(); 2636 } 2637 2638 if (NewFD->isMain()) CheckMain(NewFD); 2639 2640 // Semantic checking for this function declaration (in isolation). 2641 if (getLangOptions().CPlusPlus) { 2642 // C++-specific checks. 2643 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2644 CheckConstructor(Constructor); 2645 } else if (isa<CXXDestructorDecl>(NewFD)) { 2646 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2647 QualType ClassType = Context.getTypeDeclType(Record); 2648 if (!ClassType->isDependentType()) { 2649 ClassType = Context.getCanonicalType(ClassType); 2650 DeclarationName Name 2651 = Context.DeclarationNames.getCXXDestructorName(ClassType); 2652 if (NewFD->getDeclName() != Name) { 2653 Diag(NewFD->getLocation(), diag::err_destructor_name); 2654 return NewFD->setInvalidDecl(); 2655 } 2656 } 2657 Record->setUserDeclaredDestructor(true); 2658 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2659 // user-defined destructor. 2660 Record->setPOD(false); 2661 2662 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2663 // declared destructor. 2664 // FIXME: C++0x: don't do this for "= default" destructors 2665 Record->setHasTrivialDestructor(false); 2666 } else if (CXXConversionDecl *Conversion 2667 = dyn_cast<CXXConversionDecl>(NewFD)) 2668 ActOnConversionDeclarator(Conversion); 2669 2670 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2671 if (NewFD->isOverloadedOperator() && 2672 CheckOverloadedOperatorDeclaration(NewFD)) 2673 return NewFD->setInvalidDecl(); 2674 } 2675 2676 // C99 6.7.4p6: 2677 // [... ] For a function with external linkage, the following 2678 // restrictions apply: [...] If all of the file scope declarations 2679 // for a function in a translation unit include the inline 2680 // function specifier without extern, then the definition in that 2681 // translation unit is an inline definition. An inline definition 2682 // does not provide an external definition for the function, and 2683 // does not forbid an external definition in another translation 2684 // unit. 2685 // 2686 // Here we determine whether this function, in isolation, would be a 2687 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2688 // previous declarations. 2689 if (NewFD->isInline() && getLangOptions().C99 && 2690 NewFD->getStorageClass() == FunctionDecl::None && 2691 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2692 NewFD->setC99InlineDefinition(true); 2693 2694 // Check for a previous declaration of this name. 2695 if (!PrevDecl && NewFD->isExternC(Context)) { 2696 // Since we did not find anything by this name and we're declaring 2697 // an extern "C" function, look for a non-visible extern "C" 2698 // declaration with the same name. 2699 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2700 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2701 if (Pos != LocallyScopedExternalDecls.end()) 2702 PrevDecl = Pos->second; 2703 } 2704 2705 // Merge or overload the declaration with an existing declaration of 2706 // the same name, if appropriate. 2707 if (PrevDecl) { 2708 // Determine whether NewFD is an overload of PrevDecl or 2709 // a declaration that requires merging. If it's an overload, 2710 // there's no more work to do here; we'll just add the new 2711 // function to the scope. 2712 OverloadedFunctionDecl::function_iterator MatchedDecl; 2713 2714 if (!getLangOptions().CPlusPlus && 2715 AllowOverloadingOfFunction(PrevDecl, Context)) { 2716 OverloadableAttrRequired = true; 2717 2718 // Functions marked "overloadable" must have a prototype (that 2719 // we can't get through declaration merging). 2720 if (!NewFD->getType()->getAsFunctionProtoType()) { 2721 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2722 << NewFD; 2723 Redeclaration = true; 2724 2725 // Turn this into a variadic function with no parameters. 2726 QualType R = Context.getFunctionType( 2727 NewFD->getType()->getAsFunctionType()->getResultType(), 2728 0, 0, true, 0); 2729 NewFD->setType(R); 2730 return NewFD->setInvalidDecl(); 2731 } 2732 } 2733 2734 if (PrevDecl && 2735 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2736 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && 2737 !isa<UsingDecl>(PrevDecl)) { 2738 Redeclaration = true; 2739 Decl *OldDecl = PrevDecl; 2740 2741 // If PrevDecl was an overloaded function, extract the 2742 // FunctionDecl that matched. 2743 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2744 OldDecl = *MatchedDecl; 2745 2746 // NewFD and OldDecl represent declarations that need to be 2747 // merged. 2748 if (MergeFunctionDecl(NewFD, OldDecl)) 2749 return NewFD->setInvalidDecl(); 2750 2751 if (FunctionTemplateDecl *OldTemplateDecl 2752 = dyn_cast<FunctionTemplateDecl>(OldDecl)) 2753 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 2754 else { 2755 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 2756 NewFD->setAccess(OldDecl->getAccess()); 2757 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2758 } 2759 } 2760 } 2761 2762 // In C++, check default arguments now that we have merged decls. Unless 2763 // the lexical context is the class, because in this case this is done 2764 // during delayed parsing anyway. 2765 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2766 CheckCXXDefaultArguments(NewFD); 2767} 2768 2769void Sema::CheckMain(FunctionDecl* FD) { 2770 // C++ [basic.start.main]p3: A program that declares main to be inline 2771 // or static is ill-formed. 2772 // C99 6.7.4p4: In a hosted environment, the inline function specifier 2773 // shall not appear in a declaration of main. 2774 // static main is not an error under C99, but we should warn about it. 2775 bool isInline = FD->isInline(); 2776 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 2777 if (isInline || isStatic) { 2778 unsigned diagID = diag::warn_unusual_main_decl; 2779 if (isInline || getLangOptions().CPlusPlus) 2780 diagID = diag::err_unusual_main_decl; 2781 2782 int which = isStatic + (isInline << 1) - 1; 2783 Diag(FD->getLocation(), diagID) << which; 2784 } 2785 2786 QualType T = FD->getType(); 2787 assert(T->isFunctionType() && "function decl is not of function type"); 2788 const FunctionType* FT = T->getAsFunctionType(); 2789 2790 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 2791 // TODO: add a replacement fixit to turn the return type into 'int'. 2792 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 2793 FD->setInvalidDecl(true); 2794 } 2795 2796 // Treat protoless main() as nullary. 2797 if (isa<FunctionNoProtoType>(FT)) return; 2798 2799 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 2800 unsigned nparams = FTP->getNumArgs(); 2801 assert(FD->getNumParams() == nparams); 2802 2803 if (nparams > 3) { 2804 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 2805 FD->setInvalidDecl(true); 2806 nparams = 3; 2807 } 2808 2809 // FIXME: a lot of the following diagnostics would be improved 2810 // if we had some location information about types. 2811 2812 QualType CharPP = 2813 Context.getPointerType(Context.getPointerType(Context.CharTy)); 2814 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 2815 2816 for (unsigned i = 0; i < nparams; ++i) { 2817 QualType AT = FTP->getArgType(i); 2818 2819 bool mismatch = true; 2820 2821 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 2822 mismatch = false; 2823 else if (Expected[i] == CharPP) { 2824 // As an extension, the following forms are okay: 2825 // char const ** 2826 // char const * const * 2827 // char * const * 2828 2829 QualifierSet qs; 2830 const PointerType* PT; 2831 if ((PT = qs.strip(AT)->getAsPointerType()) && 2832 (PT = qs.strip(PT->getPointeeType())->getAsPointerType()) && 2833 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 2834 qs.removeConst(); 2835 mismatch = !qs.empty(); 2836 } 2837 } 2838 2839 if (mismatch) { 2840 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 2841 // TODO: suggest replacing given type with expected type 2842 FD->setInvalidDecl(true); 2843 } 2844 } 2845 2846 if (nparams == 1 && !FD->isInvalidDecl()) { 2847 Diag(FD->getLocation(), diag::warn_main_one_arg); 2848 } 2849} 2850 2851bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2852 // FIXME: Need strict checking. In C89, we need to check for 2853 // any assignment, increment, decrement, function-calls, or 2854 // commas outside of a sizeof. In C99, it's the same list, 2855 // except that the aforementioned are allowed in unevaluated 2856 // expressions. Everything else falls under the 2857 // "may accept other forms of constant expressions" exception. 2858 // (We never end up here for C++, so the constant expression 2859 // rules there don't matter.) 2860 if (Init->isConstantInitializer(Context)) 2861 return false; 2862 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2863 << Init->getSourceRange(); 2864 return true; 2865} 2866 2867void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2868 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2869} 2870 2871/// AddInitializerToDecl - Adds the initializer Init to the 2872/// declaration dcl. If DirectInit is true, this is C++ direct 2873/// initialization rather than copy initialization. 2874void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2875 Decl *RealDecl = dcl.getAs<Decl>(); 2876 // If there is no declaration, there was an error parsing it. Just ignore 2877 // the initializer. 2878 if (RealDecl == 0) 2879 return; 2880 2881 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2882 // With declarators parsed the way they are, the parser cannot 2883 // distinguish between a normal initializer and a pure-specifier. 2884 // Thus this grotesque test. 2885 IntegerLiteral *IL; 2886 Expr *Init = static_cast<Expr *>(init.get()); 2887 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2888 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2889 if (Method->isVirtualAsWritten()) { 2890 Method->setPure(); 2891 2892 // A class is abstract if at least one function is pure virtual. 2893 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2894 } else if (!Method->isInvalidDecl()) { 2895 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2896 << Method->getDeclName() << Init->getSourceRange(); 2897 Method->setInvalidDecl(); 2898 } 2899 } else { 2900 Diag(Method->getLocation(), diag::err_member_function_initialization) 2901 << Method->getDeclName() << Init->getSourceRange(); 2902 Method->setInvalidDecl(); 2903 } 2904 return; 2905 } 2906 2907 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2908 if (!VDecl) { 2909 if (getLangOptions().CPlusPlus && 2910 RealDecl->getLexicalDeclContext()->isRecord() && 2911 isa<NamedDecl>(RealDecl)) 2912 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2913 << cast<NamedDecl>(RealDecl)->getDeclName(); 2914 else 2915 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2916 RealDecl->setInvalidDecl(); 2917 return; 2918 } 2919 2920 if (!VDecl->getType()->isArrayType() && 2921 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2922 diag::err_typecheck_decl_incomplete_type)) { 2923 RealDecl->setInvalidDecl(); 2924 return; 2925 } 2926 2927 const VarDecl *Def = 0; 2928 if (VDecl->getDefinition(Def)) { 2929 Diag(VDecl->getLocation(), diag::err_redefinition) 2930 << VDecl->getDeclName(); 2931 Diag(Def->getLocation(), diag::note_previous_definition); 2932 VDecl->setInvalidDecl(); 2933 return; 2934 } 2935 2936 // Take ownership of the expression, now that we're sure we have somewhere 2937 // to put it. 2938 Expr *Init = init.takeAs<Expr>(); 2939 assert(Init && "missing initializer"); 2940 2941 // Get the decls type and save a reference for later, since 2942 // CheckInitializerTypes may change it. 2943 QualType DclT = VDecl->getType(), SavT = DclT; 2944 if (VDecl->isBlockVarDecl()) { 2945 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2946 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2947 VDecl->setInvalidDecl(); 2948 } else if (!VDecl->isInvalidDecl()) { 2949 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2950 VDecl->getDeclName(), DirectInit)) 2951 VDecl->setInvalidDecl(); 2952 2953 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2954 // Don't check invalid declarations to avoid emitting useless diagnostics. 2955 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2956 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2957 CheckForConstantInitializer(Init, DclT); 2958 } 2959 } 2960 } else if (VDecl->isStaticDataMember() && 2961 VDecl->getLexicalDeclContext()->isRecord()) { 2962 // This is an in-class initialization for a static data member, e.g., 2963 // 2964 // struct S { 2965 // static const int value = 17; 2966 // }; 2967 2968 // Attach the initializer 2969 VDecl->setInit(Context, Init); 2970 2971 // C++ [class.mem]p4: 2972 // A member-declarator can contain a constant-initializer only 2973 // if it declares a static member (9.4) of const integral or 2974 // const enumeration type, see 9.4.2. 2975 QualType T = VDecl->getType(); 2976 if (!T->isDependentType() && 2977 (!Context.getCanonicalType(T).isConstQualified() || 2978 !T->isIntegralType())) { 2979 Diag(VDecl->getLocation(), diag::err_member_initialization) 2980 << VDecl->getDeclName() << Init->getSourceRange(); 2981 VDecl->setInvalidDecl(); 2982 } else { 2983 // C++ [class.static.data]p4: 2984 // If a static data member is of const integral or const 2985 // enumeration type, its declaration in the class definition 2986 // can specify a constant-initializer which shall be an 2987 // integral constant expression (5.19). 2988 if (!Init->isTypeDependent() && 2989 !Init->getType()->isIntegralType()) { 2990 // We have a non-dependent, non-integral or enumeration type. 2991 Diag(Init->getSourceRange().getBegin(), 2992 diag::err_in_class_initializer_non_integral_type) 2993 << Init->getType() << Init->getSourceRange(); 2994 VDecl->setInvalidDecl(); 2995 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2996 // Check whether the expression is a constant expression. 2997 llvm::APSInt Value; 2998 SourceLocation Loc; 2999 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3000 Diag(Loc, diag::err_in_class_initializer_non_constant) 3001 << Init->getSourceRange(); 3002 VDecl->setInvalidDecl(); 3003 } else if (!VDecl->getType()->isDependentType()) 3004 ImpCastExprToType(Init, VDecl->getType()); 3005 } 3006 } 3007 } else if (VDecl->isFileVarDecl()) { 3008 if (VDecl->getStorageClass() == VarDecl::Extern) 3009 Diag(VDecl->getLocation(), diag::warn_extern_init); 3010 if (!VDecl->isInvalidDecl()) 3011 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3012 VDecl->getDeclName(), DirectInit)) 3013 VDecl->setInvalidDecl(); 3014 3015 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3016 // Don't check invalid declarations to avoid emitting useless diagnostics. 3017 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3018 // C99 6.7.8p4. All file scoped initializers need to be constant. 3019 CheckForConstantInitializer(Init, DclT); 3020 } 3021 } 3022 // If the type changed, it means we had an incomplete type that was 3023 // completed by the initializer. For example: 3024 // int ary[] = { 1, 3, 5 }; 3025 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3026 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3027 VDecl->setType(DclT); 3028 Init->setType(DclT); 3029 } 3030 3031 // Attach the initializer to the decl. 3032 VDecl->setInit(Context, Init); 3033 3034 // If the previous declaration of VDecl was a tentative definition, 3035 // remove it from the set of tentative definitions. 3036 if (VDecl->getPreviousDeclaration() && 3037 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3038 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 3039 = TentativeDefinitions.find(VDecl->getDeclName()); 3040 assert(Pos != TentativeDefinitions.end() && 3041 "Unrecorded tentative definition?"); 3042 TentativeDefinitions.erase(Pos); 3043 } 3044 3045 return; 3046} 3047 3048void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3049 bool TypeContainsUndeducedAuto) { 3050 Decl *RealDecl = dcl.getAs<Decl>(); 3051 3052 // If there is no declaration, there was an error parsing it. Just ignore it. 3053 if (RealDecl == 0) 3054 return; 3055 3056 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3057 QualType Type = Var->getType(); 3058 3059 // Record tentative definitions. 3060 if (Var->isTentativeDefinition(Context)) 3061 TentativeDefinitions[Var->getDeclName()] = Var; 3062 3063 // C++ [dcl.init.ref]p3: 3064 // The initializer can be omitted for a reference only in a 3065 // parameter declaration (8.3.5), in the declaration of a 3066 // function return type, in the declaration of a class member 3067 // within its class declaration (9.2), and where the extern 3068 // specifier is explicitly used. 3069 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3070 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3071 << Var->getDeclName() 3072 << SourceRange(Var->getLocation(), Var->getLocation()); 3073 Var->setInvalidDecl(); 3074 return; 3075 } 3076 3077 // C++0x [dcl.spec.auto]p3 3078 if (TypeContainsUndeducedAuto) { 3079 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3080 << Var->getDeclName() << Type; 3081 Var->setInvalidDecl(); 3082 return; 3083 } 3084 3085 // C++ [dcl.init]p9: 3086 // 3087 // If no initializer is specified for an object, and the object 3088 // is of (possibly cv-qualified) non-POD class type (or array 3089 // thereof), the object shall be default-initialized; if the 3090 // object is of const-qualified type, the underlying class type 3091 // shall have a user-declared default constructor. 3092 if (getLangOptions().CPlusPlus) { 3093 QualType InitType = Type; 3094 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3095 InitType = Array->getElementType(); 3096 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 3097 InitType->isRecordType() && !InitType->isDependentType()) { 3098 CXXRecordDecl *RD = 3099 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 3100 CXXConstructorDecl *Constructor = 0; 3101 if (!RequireCompleteType(Var->getLocation(), InitType, 3102 diag::err_invalid_incomplete_type_use)) 3103 Constructor 3104 = PerformInitializationByConstructor(InitType, 0, 0, 3105 Var->getLocation(), 3106 SourceRange(Var->getLocation(), 3107 Var->getLocation()), 3108 Var->getDeclName(), 3109 IK_Default); 3110 if (!Constructor) 3111 Var->setInvalidDecl(); 3112 else { 3113 if (!RD->hasTrivialConstructor()) 3114 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 3115 // FIXME. Must do all that is needed to destroy the object 3116 // on scope exit. For now, just mark the destructor as used. 3117 MarkDestructorReferenced(Var->getLocation(), InitType); 3118 } 3119 } 3120 } 3121 3122#if 0 3123 // FIXME: Temporarily disabled because we are not properly parsing 3124 // linkage specifications on declarations, e.g., 3125 // 3126 // extern "C" const CGPoint CGPointerZero; 3127 // 3128 // C++ [dcl.init]p9: 3129 // 3130 // If no initializer is specified for an object, and the 3131 // object is of (possibly cv-qualified) non-POD class type (or 3132 // array thereof), the object shall be default-initialized; if 3133 // the object is of const-qualified type, the underlying class 3134 // type shall have a user-declared default 3135 // constructor. Otherwise, if no initializer is specified for 3136 // an object, the object and its subobjects, if any, have an 3137 // indeterminate initial value; if the object or any of its 3138 // subobjects are of const-qualified type, the program is 3139 // ill-formed. 3140 // 3141 // This isn't technically an error in C, so we don't diagnose it. 3142 // 3143 // FIXME: Actually perform the POD/user-defined default 3144 // constructor check. 3145 if (getLangOptions().CPlusPlus && 3146 Context.getCanonicalType(Type).isConstQualified() && 3147 !Var->hasExternalStorage()) 3148 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3149 << Var->getName() 3150 << SourceRange(Var->getLocation(), Var->getLocation()); 3151#endif 3152 } 3153} 3154 3155Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3156 DeclPtrTy *Group, 3157 unsigned NumDecls) { 3158 llvm::SmallVector<Decl*, 8> Decls; 3159 3160 if (DS.isTypeSpecOwned()) 3161 Decls.push_back((Decl*)DS.getTypeRep()); 3162 3163 for (unsigned i = 0; i != NumDecls; ++i) 3164 if (Decl *D = Group[i].getAs<Decl>()) 3165 Decls.push_back(D); 3166 3167 // Perform semantic analysis that depends on having fully processed both 3168 // the declarator and initializer. 3169 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3170 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3171 if (!IDecl) 3172 continue; 3173 QualType T = IDecl->getType(); 3174 3175 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3176 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3177 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3178 if (!IDecl->isInvalidDecl() && 3179 RequireCompleteType(IDecl->getLocation(), T, 3180 diag::err_typecheck_decl_incomplete_type)) 3181 IDecl->setInvalidDecl(); 3182 } 3183 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3184 // object that has file scope without an initializer, and without a 3185 // storage-class specifier or with the storage-class specifier "static", 3186 // constitutes a tentative definition. Note: A tentative definition with 3187 // external linkage is valid (C99 6.2.2p5). 3188 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3189 if (const IncompleteArrayType *ArrayT 3190 = Context.getAsIncompleteArrayType(T)) { 3191 if (RequireCompleteType(IDecl->getLocation(), 3192 ArrayT->getElementType(), 3193 diag::err_illegal_decl_array_incomplete_type)) 3194 IDecl->setInvalidDecl(); 3195 } 3196 else if (IDecl->getStorageClass() == VarDecl::Static) { 3197 // C99 6.9.2p3: If the declaration of an identifier for an object is 3198 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3199 // declared type shall not be an incomplete type. 3200 // NOTE: code such as the following 3201 // static struct s; 3202 // struct s { int a; }; 3203 // is accepted by gcc. Hence here we issue a warning instead of 3204 // an error and we do not invalidate the static declaration. 3205 // NOTE: to avoid multiple warnings, only check the first declaration. 3206 if (IDecl->getPreviousDeclaration() == 0) 3207 RequireCompleteType(IDecl->getLocation(), T, 3208 diag::ext_typecheck_decl_incomplete_type); 3209 } 3210 } 3211 } 3212 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3213 Decls.data(), Decls.size())); 3214} 3215 3216 3217/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3218/// to introduce parameters into function prototype scope. 3219Sema::DeclPtrTy 3220Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3221 const DeclSpec &DS = D.getDeclSpec(); 3222 3223 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3224 VarDecl::StorageClass StorageClass = VarDecl::None; 3225 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3226 StorageClass = VarDecl::Register; 3227 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3228 Diag(DS.getStorageClassSpecLoc(), 3229 diag::err_invalid_storage_class_in_func_decl); 3230 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3231 } 3232 3233 if (D.getDeclSpec().isThreadSpecified()) 3234 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3235 3236 DiagnoseFunctionSpecifiers(D); 3237 3238 // Check that there are no default arguments inside the type of this 3239 // parameter (C++ only). 3240 if (getLangOptions().CPlusPlus) 3241 CheckExtraCXXDefaultArguments(D); 3242 3243 TagDecl *OwnedDecl = 0; 3244 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 3245 3246 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3247 // C++ [dcl.fct]p6: 3248 // Types shall not be defined in return or parameter types. 3249 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3250 << Context.getTypeDeclType(OwnedDecl); 3251 } 3252 3253 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3254 // Can this happen for params? We already checked that they don't conflict 3255 // among each other. Here they can only shadow globals, which is ok. 3256 IdentifierInfo *II = D.getIdentifier(); 3257 if (II) { 3258 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 3259 if (PrevDecl->isTemplateParameter()) { 3260 // Maybe we will complain about the shadowed template parameter. 3261 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3262 // Just pretend that we didn't see the previous declaration. 3263 PrevDecl = 0; 3264 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3265 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3266 3267 // Recover by removing the name 3268 II = 0; 3269 D.SetIdentifier(0, D.getIdentifierLoc()); 3270 } 3271 } 3272 } 3273 3274 // Parameters can not be abstract class types. 3275 // For record types, this is done by the AbstractClassUsageDiagnoser once 3276 // the class has been completely parsed. 3277 if (!CurContext->isRecord() && 3278 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3279 diag::err_abstract_type_in_decl, 3280 AbstractParamType)) 3281 D.setInvalidType(true); 3282 3283 QualType T = adjustParameterType(parmDeclType); 3284 3285 ParmVarDecl *New; 3286 if (T == parmDeclType) // parameter type did not need adjustment 3287 New = ParmVarDecl::Create(Context, CurContext, 3288 D.getIdentifierLoc(), II, 3289 parmDeclType, StorageClass, 3290 0); 3291 else // keep track of both the adjusted and unadjusted types 3292 New = OriginalParmVarDecl::Create(Context, CurContext, 3293 D.getIdentifierLoc(), II, T, 3294 parmDeclType, StorageClass, 0); 3295 3296 if (D.isInvalidType()) 3297 New->setInvalidDecl(); 3298 3299 // Parameter declarators cannot be interface types. All ObjC objects are 3300 // passed by reference. 3301 if (T->isObjCInterfaceType()) { 3302 Diag(D.getIdentifierLoc(), 3303 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3304 New->setInvalidDecl(); 3305 } 3306 3307 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3308 if (D.getCXXScopeSpec().isSet()) { 3309 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3310 << D.getCXXScopeSpec().getRange(); 3311 New->setInvalidDecl(); 3312 } 3313 3314 // Add the parameter declaration into this scope. 3315 S->AddDecl(DeclPtrTy::make(New)); 3316 if (II) 3317 IdResolver.AddDecl(New); 3318 3319 ProcessDeclAttributes(S, New, D); 3320 3321 if (New->hasAttr<BlocksAttr>()) { 3322 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3323 } 3324 return DeclPtrTy::make(New); 3325} 3326 3327void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3328 SourceLocation LocAfterDecls) { 3329 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3330 "Not a function declarator!"); 3331 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3332 3333 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3334 // for a K&R function. 3335 if (!FTI.hasPrototype) { 3336 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3337 --i; 3338 if (FTI.ArgInfo[i].Param == 0) { 3339 std::string Code = " int "; 3340 Code += FTI.ArgInfo[i].Ident->getName(); 3341 Code += ";\n"; 3342 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3343 << FTI.ArgInfo[i].Ident 3344 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3345 3346 // Implicitly declare the argument as type 'int' for lack of a better 3347 // type. 3348 DeclSpec DS; 3349 const char* PrevSpec; // unused 3350 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3351 PrevSpec); 3352 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3353 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3354 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3355 } 3356 } 3357 } 3358} 3359 3360Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3361 Declarator &D) { 3362 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3363 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3364 "Not a function declarator!"); 3365 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3366 3367 if (FTI.hasPrototype) { 3368 // FIXME: Diagnose arguments without names in C. 3369 } 3370 3371 Scope *ParentScope = FnBodyScope->getParent(); 3372 3373 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3374 MultiTemplateParamsArg(*this), 3375 /*IsFunctionDefinition=*/true); 3376 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3377} 3378 3379Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3380 if (!D) 3381 return D; 3382 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 3383 3384 CurFunctionNeedsScopeChecking = false; 3385 3386 // See if this is a redefinition. 3387 const FunctionDecl *Definition; 3388 if (FD->getBody(Definition)) { 3389 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3390 Diag(Definition->getLocation(), diag::note_previous_definition); 3391 } 3392 3393 // Builtin functions cannot be defined. 3394 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3395 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3396 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3397 FD->setInvalidDecl(); 3398 } 3399 } 3400 3401 // The return type of a function definition must be complete 3402 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3403 QualType ResultType = FD->getResultType(); 3404 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3405 !FD->isInvalidDecl() && 3406 RequireCompleteType(FD->getLocation(), ResultType, 3407 diag::err_func_def_incomplete_result)) 3408 FD->setInvalidDecl(); 3409 3410 // GNU warning -Wmissing-prototypes: 3411 // Warn if a global function is defined without a previous 3412 // prototype declaration. This warning is issued even if the 3413 // definition itself provides a prototype. The aim is to detect 3414 // global functions that fail to be declared in header files. 3415 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3416 !FD->isMain()) { 3417 bool MissingPrototype = true; 3418 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3419 Prev; Prev = Prev->getPreviousDeclaration()) { 3420 // Ignore any declarations that occur in function or method 3421 // scope, because they aren't visible from the header. 3422 if (Prev->getDeclContext()->isFunctionOrMethod()) 3423 continue; 3424 3425 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3426 break; 3427 } 3428 3429 if (MissingPrototype) 3430 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3431 } 3432 3433 if (FnBodyScope) 3434 PushDeclContext(FnBodyScope, FD); 3435 3436 // Check the validity of our function parameters 3437 CheckParmsForFunctionDef(FD); 3438 3439 // Introduce our parameters into the function scope 3440 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3441 ParmVarDecl *Param = FD->getParamDecl(p); 3442 Param->setOwningFunction(FD); 3443 3444 // If this has an identifier, add it to the scope stack. 3445 if (Param->getIdentifier() && FnBodyScope) 3446 PushOnScopeChains(Param, FnBodyScope); 3447 } 3448 3449 // Checking attributes of current function definition 3450 // dllimport attribute. 3451 if (FD->getAttr<DLLImportAttr>() && 3452 (!FD->getAttr<DLLExportAttr>())) { 3453 // dllimport attribute cannot be applied to definition. 3454 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3455 Diag(FD->getLocation(), 3456 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3457 << "dllimport"; 3458 FD->setInvalidDecl(); 3459 return DeclPtrTy::make(FD); 3460 } else { 3461 // If a symbol previously declared dllimport is later defined, the 3462 // attribute is ignored in subsequent references, and a warning is 3463 // emitted. 3464 Diag(FD->getLocation(), 3465 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3466 << FD->getNameAsCString() << "dllimport"; 3467 } 3468 } 3469 return DeclPtrTy::make(FD); 3470} 3471 3472Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3473 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3474} 3475 3476Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3477 bool IsInstantiation) { 3478 Decl *dcl = D.getAs<Decl>(); 3479 Stmt *Body = BodyArg.takeAs<Stmt>(); 3480 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3481 FD->setBody(Body); 3482 if (!FD->isMain()) 3483 // C and C++ allow for main to automagically return 0. 3484 CheckFallThroughForFunctionDef(FD, Body); 3485 3486 if (!FD->isInvalidDecl()) 3487 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3488 3489 // C++ [basic.def.odr]p2: 3490 // [...] A virtual member function is used if it is not pure. [...] 3491 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3492 if (Method->isVirtual() && !Method->isPure()) 3493 MarkDeclarationReferenced(Method->getLocation(), Method); 3494 3495 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3496 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3497 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3498 MD->setBody(Body); 3499 CheckFallThroughForFunctionDef(MD, Body); 3500 MD->setEndLoc(Body->getLocEnd()); 3501 3502 if (!MD->isInvalidDecl()) 3503 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3504 } else { 3505 Body->Destroy(Context); 3506 return DeclPtrTy(); 3507 } 3508 if (!IsInstantiation) 3509 PopDeclContext(); 3510 3511 // Verify and clean out per-function state. 3512 3513 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3514 3515 // Check goto/label use. 3516 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3517 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3518 LabelStmt *L = I->second; 3519 3520 // Verify that we have no forward references left. If so, there was a goto 3521 // or address of a label taken, but no definition of it. Label fwd 3522 // definitions are indicated with a null substmt. 3523 if (L->getSubStmt() != 0) 3524 continue; 3525 3526 // Emit error. 3527 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3528 3529 // At this point, we have gotos that use the bogus label. Stitch it into 3530 // the function body so that they aren't leaked and that the AST is well 3531 // formed. 3532 if (Body == 0) { 3533 // The whole function wasn't parsed correctly, just delete this. 3534 L->Destroy(Context); 3535 continue; 3536 } 3537 3538 // Otherwise, the body is valid: we want to stitch the label decl into the 3539 // function somewhere so that it is properly owned and so that the goto 3540 // has a valid target. Do this by creating a new compound stmt with the 3541 // label in it. 3542 3543 // Give the label a sub-statement. 3544 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3545 3546 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3547 cast<CXXTryStmt>(Body)->getTryBlock() : 3548 cast<CompoundStmt>(Body); 3549 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3550 Elements.push_back(L); 3551 Compound->setStmts(Context, &Elements[0], Elements.size()); 3552 } 3553 FunctionLabelMap.clear(); 3554 3555 if (!Body) return D; 3556 3557 // Verify that that gotos and switch cases don't jump into scopes illegally. 3558 if (CurFunctionNeedsScopeChecking) 3559 DiagnoseInvalidJumps(Body); 3560 3561 // C++ constructors that have function-try-blocks can't have return 3562 // statements in the handlers of that block. (C++ [except.handle]p14) 3563 // Verify this. 3564 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3565 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3566 3567 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3568 Destructor->computeBaseOrMembersToDestroy(Context); 3569 return D; 3570} 3571 3572/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3573/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3574NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3575 IdentifierInfo &II, Scope *S) { 3576 // Before we produce a declaration for an implicitly defined 3577 // function, see whether there was a locally-scoped declaration of 3578 // this name as a function or variable. If so, use that 3579 // (non-visible) declaration, and complain about it. 3580 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3581 = LocallyScopedExternalDecls.find(&II); 3582 if (Pos != LocallyScopedExternalDecls.end()) { 3583 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3584 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3585 return Pos->second; 3586 } 3587 3588 // Extension in C99. Legal in C90, but warn about it. 3589 if (getLangOptions().C99) 3590 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3591 else 3592 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3593 3594 // FIXME: handle stuff like: 3595 // void foo() { extern float X(); } 3596 // void bar() { X(); } <-- implicit decl for X in another scope. 3597 3598 // Set a Declarator for the implicit definition: int foo(); 3599 const char *Dummy; 3600 DeclSpec DS; 3601 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3602 Error = Error; // Silence warning. 3603 assert(!Error && "Error setting up implicit decl!"); 3604 Declarator D(DS, Declarator::BlockContext); 3605 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3606 0, 0, false, SourceLocation(), 3607 false, 0,0,0, Loc, D), 3608 SourceLocation()); 3609 D.SetIdentifier(&II, Loc); 3610 3611 // Insert this function into translation-unit scope. 3612 3613 DeclContext *PrevDC = CurContext; 3614 CurContext = Context.getTranslationUnitDecl(); 3615 3616 FunctionDecl *FD = 3617 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3618 FD->setImplicit(); 3619 3620 CurContext = PrevDC; 3621 3622 AddKnownFunctionAttributes(FD); 3623 3624 return FD; 3625} 3626 3627/// \brief Adds any function attributes that we know a priori based on 3628/// the declaration of this function. 3629/// 3630/// These attributes can apply both to implicitly-declared builtins 3631/// (like __builtin___printf_chk) or to library-declared functions 3632/// like NSLog or printf. 3633void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3634 if (FD->isInvalidDecl()) 3635 return; 3636 3637 // If this is a built-in function, map its builtin attributes to 3638 // actual attributes. 3639 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3640 // Handle printf-formatting attributes. 3641 unsigned FormatIdx; 3642 bool HasVAListArg; 3643 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3644 if (!FD->getAttr<FormatAttr>()) 3645 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3646 HasVAListArg ? 0 : FormatIdx + 2)); 3647 } 3648 3649 // Mark const if we don't care about errno and that is the only 3650 // thing preventing the function from being const. This allows 3651 // IRgen to use LLVM intrinsics for such functions. 3652 if (!getLangOptions().MathErrno && 3653 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3654 if (!FD->getAttr<ConstAttr>()) 3655 FD->addAttr(::new (Context) ConstAttr()); 3656 } 3657 } 3658 3659 IdentifierInfo *Name = FD->getIdentifier(); 3660 if (!Name) 3661 return; 3662 if ((!getLangOptions().CPlusPlus && 3663 FD->getDeclContext()->isTranslationUnit()) || 3664 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3665 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3666 LinkageSpecDecl::lang_c)) { 3667 // Okay: this could be a libc/libm/Objective-C function we know 3668 // about. 3669 } else 3670 return; 3671 3672 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3673 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3674 // FIXME: We known better than our headers. 3675 const_cast<FormatAttr *>(Format)->setType("printf"); 3676 } else 3677 FD->addAttr(::new (Context) FormatAttr("printf", 1, 3678 Name->isStr("NSLogv") ? 0 : 2)); 3679 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3680 if (!FD->getAttr<FormatAttr>()) 3681 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3682 Name->isStr("vasprintf") ? 0 : 3)); 3683 } 3684} 3685 3686TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3687 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3688 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3689 3690 // Scope manipulation handled by caller. 3691 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3692 D.getIdentifierLoc(), 3693 D.getIdentifier(), 3694 T); 3695 3696 if (TagType *TT = dyn_cast<TagType>(T)) { 3697 TagDecl *TD = TT->getDecl(); 3698 3699 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3700 // keep track of the TypedefDecl. 3701 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3702 TD->setTypedefForAnonDecl(NewTD); 3703 } 3704 3705 if (D.isInvalidType()) 3706 NewTD->setInvalidDecl(); 3707 return NewTD; 3708} 3709 3710 3711/// \brief Determine whether a tag with a given kind is acceptable 3712/// as a redeclaration of the given tag declaration. 3713/// 3714/// \returns true if the new tag kind is acceptable, false otherwise. 3715bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3716 TagDecl::TagKind NewTag, 3717 SourceLocation NewTagLoc, 3718 const IdentifierInfo &Name) { 3719 // C++ [dcl.type.elab]p3: 3720 // The class-key or enum keyword present in the 3721 // elaborated-type-specifier shall agree in kind with the 3722 // declaration to which the name in theelaborated-type-specifier 3723 // refers. This rule also applies to the form of 3724 // elaborated-type-specifier that declares a class-name or 3725 // friend class since it can be construed as referring to the 3726 // definition of the class. Thus, in any 3727 // elaborated-type-specifier, the enum keyword shall be used to 3728 // refer to an enumeration (7.2), the union class-keyshall be 3729 // used to refer to a union (clause 9), and either the class or 3730 // struct class-key shall be used to refer to a class (clause 9) 3731 // declared using the class or struct class-key. 3732 TagDecl::TagKind OldTag = Previous->getTagKind(); 3733 if (OldTag == NewTag) 3734 return true; 3735 3736 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3737 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3738 // Warn about the struct/class tag mismatch. 3739 bool isTemplate = false; 3740 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3741 isTemplate = Record->getDescribedClassTemplate(); 3742 3743 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3744 << (NewTag == TagDecl::TK_class) 3745 << isTemplate << &Name 3746 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3747 OldTag == TagDecl::TK_class? "class" : "struct"); 3748 Diag(Previous->getLocation(), diag::note_previous_use); 3749 return true; 3750 } 3751 return false; 3752} 3753 3754/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3755/// former case, Name will be non-null. In the later case, Name will be null. 3756/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3757/// reference/declaration/definition of a tag. 3758Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3759 SourceLocation KWLoc, const CXXScopeSpec &SS, 3760 IdentifierInfo *Name, SourceLocation NameLoc, 3761 AttributeList *Attr, AccessSpecifier AS, 3762 MultiTemplateParamsArg TemplateParameterLists, 3763 bool &OwnedDecl) { 3764 // If this is not a definition, it must have a name. 3765 assert((Name != 0 || TK == TK_Definition) && 3766 "Nameless record must be a definition!"); 3767 3768 OwnedDecl = false; 3769 TagDecl::TagKind Kind; 3770 switch (TagSpec) { 3771 default: assert(0 && "Unknown tag type!"); 3772 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3773 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3774 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3775 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3776 } 3777 3778 if (TK != TK_Reference) { 3779 if (TemplateParameterList *TemplateParams 3780 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 3781 (TemplateParameterList**)TemplateParameterLists.get(), 3782 TemplateParameterLists.size())) { 3783 if (TemplateParams->size() > 0) { 3784 // This is a declaration or definition of a class template (which may 3785 // be a member of another template). 3786 OwnedDecl = false; 3787 DeclResult Result = CheckClassTemplate(S, TagSpec, TK, KWLoc, 3788 SS, Name, NameLoc, Attr, 3789 move(TemplateParameterLists), 3790 AS); 3791 return Result.get(); 3792 } else { 3793 // FIXME: diagnose the extraneous 'template<>', once we recover 3794 // slightly better in ParseTemplate.cpp from bogus template 3795 // parameters. 3796 } 3797 } 3798 } 3799 3800 DeclContext *SearchDC = CurContext; 3801 DeclContext *DC = CurContext; 3802 NamedDecl *PrevDecl = 0; 3803 3804 bool Invalid = false; 3805 3806 if (Name && SS.isNotEmpty()) { 3807 // We have a nested-name tag ('struct foo::bar'). 3808 3809 // Check for invalid 'foo::'. 3810 if (SS.isInvalid()) { 3811 Name = 0; 3812 goto CreateNewDecl; 3813 } 3814 3815 if (RequireCompleteDeclContext(SS)) 3816 return DeclPtrTy::make((Decl *)0); 3817 3818 DC = computeDeclContext(SS, true); 3819 SearchDC = DC; 3820 // Look-up name inside 'foo::'. 3821 PrevDecl 3822 = dyn_cast_or_null<TagDecl>( 3823 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3824 3825 // A tag 'foo::bar' must already exist. 3826 if (PrevDecl == 0) { 3827 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3828 Name = 0; 3829 Invalid = true; 3830 goto CreateNewDecl; 3831 } 3832 } else if (Name) { 3833 // If this is a named struct, check to see if there was a previous forward 3834 // declaration or definition. 3835 // FIXME: We're looking into outer scopes here, even when we 3836 // shouldn't be. Doing so can result in ambiguities that we 3837 // shouldn't be diagnosing. 3838 LookupResult R = LookupName(S, Name, LookupTagName, 3839 /*RedeclarationOnly=*/(TK != TK_Reference)); 3840 if (R.isAmbiguous()) { 3841 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3842 // FIXME: This is not best way to recover from case like: 3843 // 3844 // struct S s; 3845 // 3846 // causes needless "incomplete type" error later. 3847 Name = 0; 3848 PrevDecl = 0; 3849 Invalid = true; 3850 } 3851 else 3852 PrevDecl = R; 3853 3854 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3855 // FIXME: This makes sure that we ignore the contexts associated 3856 // with C structs, unions, and enums when looking for a matching 3857 // tag declaration or definition. See the similar lookup tweak 3858 // in Sema::LookupName; is there a better way to deal with this? 3859 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3860 SearchDC = SearchDC->getParent(); 3861 } 3862 } 3863 3864 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3865 // Maybe we will complain about the shadowed template parameter. 3866 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3867 // Just pretend that we didn't see the previous declaration. 3868 PrevDecl = 0; 3869 } 3870 3871 if (PrevDecl) { 3872 // Check whether the previous declaration is usable. 3873 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3874 3875 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3876 // If this is a use of a previous tag, or if the tag is already declared 3877 // in the same scope (so that the definition/declaration completes or 3878 // rementions the tag), reuse the decl. 3879 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3880 // Make sure that this wasn't declared as an enum and now used as a 3881 // struct or something similar. 3882 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3883 bool SafeToContinue 3884 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3885 Kind != TagDecl::TK_enum); 3886 if (SafeToContinue) 3887 Diag(KWLoc, diag::err_use_with_wrong_tag) 3888 << Name 3889 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3890 PrevTagDecl->getKindName()); 3891 else 3892 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3893 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3894 3895 if (SafeToContinue) 3896 Kind = PrevTagDecl->getTagKind(); 3897 else { 3898 // Recover by making this an anonymous redefinition. 3899 Name = 0; 3900 PrevDecl = 0; 3901 Invalid = true; 3902 } 3903 } 3904 3905 if (!Invalid) { 3906 // If this is a use, just return the declaration we found. 3907 3908 // FIXME: In the future, return a variant or some other clue 3909 // for the consumer of this Decl to know it doesn't own it. 3910 // For our current ASTs this shouldn't be a problem, but will 3911 // need to be changed with DeclGroups. 3912 if (TK == TK_Reference) 3913 return DeclPtrTy::make(PrevDecl); 3914 3915 // Diagnose attempts to redefine a tag. 3916 if (TK == TK_Definition) { 3917 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3918 Diag(NameLoc, diag::err_redefinition) << Name; 3919 Diag(Def->getLocation(), diag::note_previous_definition); 3920 // If this is a redefinition, recover by making this 3921 // struct be anonymous, which will make any later 3922 // references get the previous definition. 3923 Name = 0; 3924 PrevDecl = 0; 3925 Invalid = true; 3926 } else { 3927 // If the type is currently being defined, complain 3928 // about a nested redefinition. 3929 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3930 if (Tag->isBeingDefined()) { 3931 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3932 Diag(PrevTagDecl->getLocation(), 3933 diag::note_previous_definition); 3934 Name = 0; 3935 PrevDecl = 0; 3936 Invalid = true; 3937 } 3938 } 3939 3940 // Okay, this is definition of a previously declared or referenced 3941 // tag PrevDecl. We're going to create a new Decl for it. 3942 } 3943 } 3944 // If we get here we have (another) forward declaration or we 3945 // have a definition. Just create a new decl. 3946 } else { 3947 // If we get here, this is a definition of a new tag type in a nested 3948 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3949 // new decl/type. We set PrevDecl to NULL so that the entities 3950 // have distinct types. 3951 PrevDecl = 0; 3952 } 3953 // If we get here, we're going to create a new Decl. If PrevDecl 3954 // is non-NULL, it's a definition of the tag declared by 3955 // PrevDecl. If it's NULL, we have a new definition. 3956 } else { 3957 // PrevDecl is a namespace, template, or anything else 3958 // that lives in the IDNS_Tag identifier namespace. 3959 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3960 // The tag name clashes with a namespace name, issue an error and 3961 // recover by making this tag be anonymous. 3962 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3963 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3964 Name = 0; 3965 PrevDecl = 0; 3966 Invalid = true; 3967 } else { 3968 // The existing declaration isn't relevant to us; we're in a 3969 // new scope, so clear out the previous declaration. 3970 PrevDecl = 0; 3971 } 3972 } 3973 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3974 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3975 // C++ [basic.scope.pdecl]p5: 3976 // -- for an elaborated-type-specifier of the form 3977 // 3978 // class-key identifier 3979 // 3980 // if the elaborated-type-specifier is used in the 3981 // decl-specifier-seq or parameter-declaration-clause of a 3982 // function defined in namespace scope, the identifier is 3983 // declared as a class-name in the namespace that contains 3984 // the declaration; otherwise, except as a friend 3985 // declaration, the identifier is declared in the smallest 3986 // non-class, non-function-prototype scope that contains the 3987 // declaration. 3988 // 3989 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3990 // C structs and unions. 3991 // 3992 // GNU C also supports this behavior as part of its incomplete 3993 // enum types extension, while GNU C++ does not. 3994 // 3995 // Find the context where we'll be declaring the tag. 3996 // FIXME: We would like to maintain the current DeclContext as the 3997 // lexical context, 3998 while (SearchDC->isRecord()) 3999 SearchDC = SearchDC->getParent(); 4000 4001 // Find the scope where we'll be declaring the tag. 4002 while (S->isClassScope() || 4003 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4004 ((S->getFlags() & Scope::DeclScope) == 0) || 4005 (S->getEntity() && 4006 ((DeclContext *)S->getEntity())->isTransparentContext())) 4007 S = S->getParent(); 4008 } 4009 4010CreateNewDecl: 4011 4012 // If there is an identifier, use the location of the identifier as the 4013 // location of the decl, otherwise use the location of the struct/union 4014 // keyword. 4015 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4016 4017 // Otherwise, create a new declaration. If there is a previous 4018 // declaration of the same entity, the two will be linked via 4019 // PrevDecl. 4020 TagDecl *New; 4021 4022 if (Kind == TagDecl::TK_enum) { 4023 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4024 // enum X { A, B, C } D; D should chain to X. 4025 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4026 cast_or_null<EnumDecl>(PrevDecl)); 4027 // If this is an undefined enum, warn. 4028 if (TK != TK_Definition && !Invalid) { 4029 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4030 : diag::ext_forward_ref_enum; 4031 Diag(Loc, DK); 4032 } 4033 } else { 4034 // struct/union/class 4035 4036 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4037 // struct X { int A; } D; D should chain to X. 4038 if (getLangOptions().CPlusPlus) 4039 // FIXME: Look for a way to use RecordDecl for simple structs. 4040 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4041 cast_or_null<CXXRecordDecl>(PrevDecl)); 4042 else 4043 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4044 cast_or_null<RecordDecl>(PrevDecl)); 4045 } 4046 4047 if (Kind != TagDecl::TK_enum) { 4048 // Handle #pragma pack: if the #pragma pack stack has non-default 4049 // alignment, make up a packed attribute for this decl. These 4050 // attributes are checked when the ASTContext lays out the 4051 // structure. 4052 // 4053 // It is important for implementing the correct semantics that this 4054 // happen here (in act on tag decl). The #pragma pack stack is 4055 // maintained as a result of parser callbacks which can occur at 4056 // many points during the parsing of a struct declaration (because 4057 // the #pragma tokens are effectively skipped over during the 4058 // parsing of the struct). 4059 if (unsigned Alignment = getPragmaPackAlignment()) 4060 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 4061 } 4062 4063 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4064 // C++ [dcl.typedef]p3: 4065 // [...] Similarly, in a given scope, a class or enumeration 4066 // shall not be declared with the same name as a typedef-name 4067 // that is declared in that scope and refers to a type other 4068 // than the class or enumeration itself. 4069 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 4070 TypedefDecl *PrevTypedef = 0; 4071 if (Lookup.getKind() == LookupResult::Found) 4072 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 4073 4074 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 4075 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4076 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4077 Diag(Loc, diag::err_tag_definition_of_typedef) 4078 << Context.getTypeDeclType(New) 4079 << PrevTypedef->getUnderlyingType(); 4080 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4081 Invalid = true; 4082 } 4083 } 4084 4085 if (Invalid) 4086 New->setInvalidDecl(); 4087 4088 if (Attr) 4089 ProcessDeclAttributeList(S, New, Attr); 4090 4091 // If we're declaring or defining a tag in function prototype scope 4092 // in C, note that this type can only be used within the function. 4093 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4094 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4095 4096 // Set the lexical context. If the tag has a C++ scope specifier, the 4097 // lexical context will be different from the semantic context. 4098 New->setLexicalDeclContext(CurContext); 4099 4100 // Set the access specifier. 4101 if (!Invalid) 4102 SetMemberAccessSpecifier(New, PrevDecl, AS); 4103 4104 if (TK == TK_Definition) 4105 New->startDefinition(); 4106 4107 // If this has an identifier, add it to the scope stack. 4108 if (Name) { 4109 S = getNonFieldDeclScope(S); 4110 PushOnScopeChains(New, S); 4111 } else { 4112 CurContext->addDecl(New); 4113 } 4114 4115 // If this is the C FILE type, notify the AST context. 4116 if (IdentifierInfo *II = New->getIdentifier()) 4117 if (!New->isInvalidDecl() && 4118 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4119 II->isStr("FILE")) 4120 Context.setFILEDecl(New); 4121 4122 OwnedDecl = true; 4123 return DeclPtrTy::make(New); 4124} 4125 4126void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4127 AdjustDeclIfTemplate(TagD); 4128 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4129 4130 // Enter the tag context. 4131 PushDeclContext(S, Tag); 4132 4133 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4134 FieldCollector->StartClass(); 4135 4136 if (Record->getIdentifier()) { 4137 // C++ [class]p2: 4138 // [...] The class-name is also inserted into the scope of the 4139 // class itself; this is known as the injected-class-name. For 4140 // purposes of access checking, the injected-class-name is treated 4141 // as if it were a public member name. 4142 CXXRecordDecl *InjectedClassName 4143 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4144 CurContext, Record->getLocation(), 4145 Record->getIdentifier(), 4146 Record->getTagKeywordLoc(), 4147 Record); 4148 InjectedClassName->setImplicit(); 4149 InjectedClassName->setAccess(AS_public); 4150 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4151 InjectedClassName->setDescribedClassTemplate(Template); 4152 PushOnScopeChains(InjectedClassName, S); 4153 assert(InjectedClassName->isInjectedClassName() && 4154 "Broken injected-class-name"); 4155 } 4156 } 4157} 4158 4159void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4160 SourceLocation RBraceLoc) { 4161 AdjustDeclIfTemplate(TagD); 4162 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4163 Tag->setRBraceLoc(RBraceLoc); 4164 4165 if (isa<CXXRecordDecl>(Tag)) 4166 FieldCollector->FinishClass(); 4167 4168 // Exit this scope of this tag's definition. 4169 PopDeclContext(); 4170 4171 // Notify the consumer that we've defined a tag. 4172 Consumer.HandleTagDeclDefinition(Tag); 4173} 4174 4175// Note that FieldName may be null for anonymous bitfields. 4176bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4177 QualType FieldTy, const Expr *BitWidth) { 4178 4179 // C99 6.7.2.1p4 - verify the field type. 4180 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4181 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4182 // Handle incomplete types with specific error. 4183 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4184 return true; 4185 if (FieldName) 4186 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4187 << FieldName << FieldTy << BitWidth->getSourceRange(); 4188 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4189 << FieldTy << BitWidth->getSourceRange(); 4190 } 4191 4192 // If the bit-width is type- or value-dependent, don't try to check 4193 // it now. 4194 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4195 return false; 4196 4197 llvm::APSInt Value; 4198 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4199 return true; 4200 4201 // Zero-width bitfield is ok for anonymous field. 4202 if (Value == 0 && FieldName) 4203 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4204 4205 if (Value.isSigned() && Value.isNegative()) { 4206 if (FieldName) 4207 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4208 << FieldName << Value.toString(10); 4209 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4210 << Value.toString(10); 4211 } 4212 4213 if (!FieldTy->isDependentType()) { 4214 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4215 if (Value.getZExtValue() > TypeSize) { 4216 if (FieldName) 4217 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4218 << FieldName << (unsigned)TypeSize; 4219 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4220 << (unsigned)TypeSize; 4221 } 4222 } 4223 4224 return false; 4225} 4226 4227/// ActOnField - Each field of a struct/union/class is passed into this in order 4228/// to create a FieldDecl object for it. 4229Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4230 SourceLocation DeclStart, 4231 Declarator &D, ExprTy *BitfieldWidth) { 4232 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4233 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4234 AS_public); 4235 return DeclPtrTy::make(Res); 4236} 4237 4238/// HandleField - Analyze a field of a C struct or a C++ data member. 4239/// 4240FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4241 SourceLocation DeclStart, 4242 Declarator &D, Expr *BitWidth, 4243 AccessSpecifier AS) { 4244 IdentifierInfo *II = D.getIdentifier(); 4245 SourceLocation Loc = DeclStart; 4246 if (II) Loc = D.getIdentifierLoc(); 4247 4248 QualType T = GetTypeForDeclarator(D, S); 4249 if (getLangOptions().CPlusPlus) 4250 CheckExtraCXXDefaultArguments(D); 4251 4252 DiagnoseFunctionSpecifiers(D); 4253 4254 if (D.getDeclSpec().isThreadSpecified()) 4255 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4256 4257 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4258 4259 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4260 // Maybe we will complain about the shadowed template parameter. 4261 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4262 // Just pretend that we didn't see the previous declaration. 4263 PrevDecl = 0; 4264 } 4265 4266 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4267 PrevDecl = 0; 4268 4269 bool Mutable 4270 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4271 SourceLocation TSSL = D.getSourceRange().getBegin(); 4272 FieldDecl *NewFD 4273 = CheckFieldDecl(II, T, Record, Loc, Mutable, BitWidth, TSSL, 4274 AS, PrevDecl, &D); 4275 if (NewFD->isInvalidDecl() && PrevDecl) { 4276 // Don't introduce NewFD into scope; there's already something 4277 // with the same name in the same scope. 4278 } else if (II) { 4279 PushOnScopeChains(NewFD, S); 4280 } else 4281 Record->addDecl(NewFD); 4282 4283 return NewFD; 4284} 4285 4286/// \brief Build a new FieldDecl and check its well-formedness. 4287/// 4288/// This routine builds a new FieldDecl given the fields name, type, 4289/// record, etc. \p PrevDecl should refer to any previous declaration 4290/// with the same name and in the same scope as the field to be 4291/// created. 4292/// 4293/// \returns a new FieldDecl. 4294/// 4295/// \todo The Declarator argument is a hack. It will be removed once 4296FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4297 RecordDecl *Record, SourceLocation Loc, 4298 bool Mutable, Expr *BitWidth, 4299 SourceLocation TSSL, 4300 AccessSpecifier AS, NamedDecl *PrevDecl, 4301 Declarator *D) { 4302 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4303 bool InvalidDecl = false; 4304 if (D) InvalidDecl = D->isInvalidType(); 4305 4306 // If we receive a broken type, recover by assuming 'int' and 4307 // marking this declaration as invalid. 4308 if (T.isNull()) { 4309 InvalidDecl = true; 4310 T = Context.IntTy; 4311 } 4312 4313 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4314 // than a variably modified type. 4315 if (T->isVariablyModifiedType()) { 4316 bool SizeIsNegative; 4317 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4318 SizeIsNegative); 4319 if (!FixedTy.isNull()) { 4320 Diag(Loc, diag::warn_illegal_constant_array_size); 4321 T = FixedTy; 4322 } else { 4323 if (SizeIsNegative) 4324 Diag(Loc, diag::err_typecheck_negative_array_size); 4325 else 4326 Diag(Loc, diag::err_typecheck_field_variable_size); 4327 InvalidDecl = true; 4328 } 4329 } 4330 4331 // Fields can not have abstract class types 4332 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4333 AbstractFieldType)) 4334 InvalidDecl = true; 4335 4336 // If this is declared as a bit-field, check the bit-field. 4337 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 4338 InvalidDecl = true; 4339 DeleteExpr(BitWidth); 4340 BitWidth = 0; 4341 } 4342 4343 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 4344 Mutable, TSSL); 4345 if (InvalidDecl) 4346 NewFD->setInvalidDecl(); 4347 4348 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4349 Diag(Loc, diag::err_duplicate_member) << II; 4350 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4351 NewFD->setInvalidDecl(); 4352 } 4353 4354 if (getLangOptions().CPlusPlus) { 4355 QualType EltTy = Context.getBaseElementType(T); 4356 4357 if (const RecordType *RT = EltTy->getAsRecordType()) { 4358 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4359 4360 if (!RDecl->hasTrivialConstructor()) 4361 cast<CXXRecordDecl>(Record)->setHasTrivialConstructor(false); 4362 if (!RDecl->hasTrivialCopyConstructor()) 4363 cast<CXXRecordDecl>(Record)->setHasTrivialCopyConstructor(false); 4364 if (!RDecl->hasTrivialCopyAssignment()) 4365 cast<CXXRecordDecl>(Record)->setHasTrivialCopyAssignment(false); 4366 if (!RDecl->hasTrivialDestructor()) 4367 cast<CXXRecordDecl>(Record)->setHasTrivialDestructor(false); 4368 4369 // C++ 9.5p1: An object of a class with a non-trivial 4370 // constructor, a non-trivial copy constructor, a non-trivial 4371 // destructor, or a non-trivial copy assignment operator 4372 // cannot be a member of a union, nor can an array of such 4373 // objects. 4374 // TODO: C++0x alters this restriction significantly. 4375 if (Record->isUnion()) { 4376 // We check for copy constructors before constructors 4377 // because otherwise we'll never get complaints about 4378 // copy constructors. 4379 4380 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4381 4382 CXXSpecialMember member; 4383 if (!RDecl->hasTrivialCopyConstructor()) 4384 member = CXXCopyConstructor; 4385 else if (!RDecl->hasTrivialConstructor()) 4386 member = CXXDefaultConstructor; 4387 else if (!RDecl->hasTrivialCopyAssignment()) 4388 member = CXXCopyAssignment; 4389 else if (!RDecl->hasTrivialDestructor()) 4390 member = CXXDestructor; 4391 else 4392 member = invalid; 4393 4394 if (member != invalid) { 4395 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4396 DiagnoseNontrivial(RT, member); 4397 NewFD->setInvalidDecl(); 4398 } 4399 } 4400 } 4401 } 4402 4403 if (getLangOptions().CPlusPlus && !T->isPODType()) 4404 cast<CXXRecordDecl>(Record)->setPOD(false); 4405 4406 // FIXME: We need to pass in the attributes given an AST 4407 // representation, not a parser representation. 4408 if (D) 4409 // FIXME: What to pass instead of TUScope? 4410 ProcessDeclAttributes(TUScope, NewFD, *D); 4411 4412 if (T.isObjCGCWeak()) 4413 Diag(Loc, diag::warn_attribute_weak_on_field); 4414 4415 NewFD->setAccess(AS); 4416 4417 // C++ [dcl.init.aggr]p1: 4418 // An aggregate is an array or a class (clause 9) with [...] no 4419 // private or protected non-static data members (clause 11). 4420 // A POD must be an aggregate. 4421 if (getLangOptions().CPlusPlus && 4422 (AS == AS_private || AS == AS_protected)) { 4423 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4424 CXXRecord->setAggregate(false); 4425 CXXRecord->setPOD(false); 4426 } 4427 4428 return NewFD; 4429} 4430 4431/// DiagnoseNontrivial - Given that a class has a non-trivial 4432/// special member, figure out why. 4433void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4434 QualType QT(T, 0U); 4435 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4436 4437 // Check whether the member was user-declared. 4438 switch (member) { 4439 case CXXDefaultConstructor: 4440 if (RD->hasUserDeclaredConstructor()) { 4441 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4442 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4443 if (!ci->isImplicitlyDefined(Context)) { 4444 SourceLocation CtorLoc = ci->getLocation(); 4445 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4446 return; 4447 } 4448 4449 assert(0 && "found no user-declared constructors"); 4450 return; 4451 } 4452 break; 4453 4454 case CXXCopyConstructor: 4455 if (RD->hasUserDeclaredCopyConstructor()) { 4456 SourceLocation CtorLoc = 4457 RD->getCopyConstructor(Context, 0)->getLocation(); 4458 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4459 return; 4460 } 4461 break; 4462 4463 case CXXCopyAssignment: 4464 if (RD->hasUserDeclaredCopyAssignment()) { 4465 // FIXME: this should use the location of the copy 4466 // assignment, not the type. 4467 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4468 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4469 return; 4470 } 4471 break; 4472 4473 case CXXDestructor: 4474 if (RD->hasUserDeclaredDestructor()) { 4475 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4476 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4477 return; 4478 } 4479 break; 4480 } 4481 4482 typedef CXXRecordDecl::base_class_iterator base_iter; 4483 4484 // Virtual bases and members inhibit trivial copying/construction, 4485 // but not trivial destruction. 4486 if (member != CXXDestructor) { 4487 // Check for virtual bases. vbases includes indirect virtual bases, 4488 // so we just iterate through the direct bases. 4489 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4490 if (bi->isVirtual()) { 4491 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4492 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4493 return; 4494 } 4495 4496 // Check for virtual methods. 4497 typedef CXXRecordDecl::method_iterator meth_iter; 4498 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4499 ++mi) { 4500 if (mi->isVirtual()) { 4501 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4502 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4503 return; 4504 } 4505 } 4506 } 4507 4508 bool (CXXRecordDecl::*hasTrivial)() const; 4509 switch (member) { 4510 case CXXDefaultConstructor: 4511 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4512 case CXXCopyConstructor: 4513 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4514 case CXXCopyAssignment: 4515 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4516 case CXXDestructor: 4517 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 4518 default: 4519 assert(0 && "unexpected special member"); return; 4520 } 4521 4522 // Check for nontrivial bases (and recurse). 4523 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 4524 const RecordType *BaseRT = bi->getType()->getAsRecordType(); 4525 assert(BaseRT); 4526 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 4527 if (!(BaseRecTy->*hasTrivial)()) { 4528 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4529 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 4530 DiagnoseNontrivial(BaseRT, member); 4531 return; 4532 } 4533 } 4534 4535 // Check for nontrivial members (and recurse). 4536 typedef RecordDecl::field_iterator field_iter; 4537 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 4538 ++fi) { 4539 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 4540 if (const RecordType *EltRT = EltTy->getAsRecordType()) { 4541 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 4542 4543 if (!(EltRD->*hasTrivial)()) { 4544 SourceLocation FLoc = (*fi)->getLocation(); 4545 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 4546 DiagnoseNontrivial(EltRT, member); 4547 return; 4548 } 4549 } 4550 } 4551 4552 assert(0 && "found no explanation for non-trivial member"); 4553} 4554 4555/// TranslateIvarVisibility - Translate visibility from a token ID to an 4556/// AST enum value. 4557static ObjCIvarDecl::AccessControl 4558TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 4559 switch (ivarVisibility) { 4560 default: assert(0 && "Unknown visitibility kind"); 4561 case tok::objc_private: return ObjCIvarDecl::Private; 4562 case tok::objc_public: return ObjCIvarDecl::Public; 4563 case tok::objc_protected: return ObjCIvarDecl::Protected; 4564 case tok::objc_package: return ObjCIvarDecl::Package; 4565 } 4566} 4567 4568/// ActOnIvar - Each ivar field of an objective-c class is passed into this 4569/// in order to create an IvarDecl object for it. 4570Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 4571 SourceLocation DeclStart, 4572 DeclPtrTy IntfDecl, 4573 Declarator &D, ExprTy *BitfieldWidth, 4574 tok::ObjCKeywordKind Visibility) { 4575 4576 IdentifierInfo *II = D.getIdentifier(); 4577 Expr *BitWidth = (Expr*)BitfieldWidth; 4578 SourceLocation Loc = DeclStart; 4579 if (II) Loc = D.getIdentifierLoc(); 4580 4581 // FIXME: Unnamed fields can be handled in various different ways, for 4582 // example, unnamed unions inject all members into the struct namespace! 4583 4584 QualType T = GetTypeForDeclarator(D, S); 4585 4586 if (BitWidth) { 4587 // 6.7.2.1p3, 6.7.2.1p4 4588 if (VerifyBitField(Loc, II, T, BitWidth)) { 4589 D.setInvalidType(); 4590 DeleteExpr(BitWidth); 4591 BitWidth = 0; 4592 } 4593 } else { 4594 // Not a bitfield. 4595 4596 // validate II. 4597 4598 } 4599 4600 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4601 // than a variably modified type. 4602 if (T->isVariablyModifiedType()) { 4603 Diag(Loc, diag::err_typecheck_ivar_variable_size); 4604 D.setInvalidType(); 4605 } 4606 4607 // Get the visibility (access control) for this ivar. 4608 ObjCIvarDecl::AccessControl ac = 4609 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 4610 : ObjCIvarDecl::None; 4611 // Must set ivar's DeclContext to its enclosing interface. 4612 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4613 DeclContext *EnclosingContext; 4614 if (ObjCImplementationDecl *IMPDecl = 4615 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4616 // Case of ivar declared in an implementation. Context is that of its class. 4617 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4618 assert(IDecl && "No class- ActOnIvar"); 4619 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4620 } 4621 else 4622 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4623 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4624 4625 // Construct the decl. 4626 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4627 EnclosingContext, Loc, II, T,ac, 4628 (Expr *)BitfieldWidth); 4629 4630 if (II) { 4631 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4632 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4633 && !isa<TagDecl>(PrevDecl)) { 4634 Diag(Loc, diag::err_duplicate_member) << II; 4635 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4636 NewID->setInvalidDecl(); 4637 } 4638 } 4639 4640 // Process attributes attached to the ivar. 4641 ProcessDeclAttributes(S, NewID, D); 4642 4643 if (D.isInvalidType()) 4644 NewID->setInvalidDecl(); 4645 4646 if (II) { 4647 // FIXME: When interfaces are DeclContexts, we'll need to add 4648 // these to the interface. 4649 S->AddDecl(DeclPtrTy::make(NewID)); 4650 IdResolver.AddDecl(NewID); 4651 } 4652 4653 return DeclPtrTy::make(NewID); 4654} 4655 4656void Sema::ActOnFields(Scope* S, 4657 SourceLocation RecLoc, DeclPtrTy RecDecl, 4658 DeclPtrTy *Fields, unsigned NumFields, 4659 SourceLocation LBrac, SourceLocation RBrac, 4660 AttributeList *Attr) { 4661 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4662 assert(EnclosingDecl && "missing record or interface decl"); 4663 4664 // If the decl this is being inserted into is invalid, then it may be a 4665 // redeclaration or some other bogus case. Don't try to add fields to it. 4666 if (EnclosingDecl->isInvalidDecl()) { 4667 // FIXME: Deallocate fields? 4668 return; 4669 } 4670 4671 4672 // Verify that all the fields are okay. 4673 unsigned NumNamedMembers = 0; 4674 llvm::SmallVector<FieldDecl*, 32> RecFields; 4675 4676 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4677 for (unsigned i = 0; i != NumFields; ++i) { 4678 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4679 4680 // Get the type for the field. 4681 Type *FDTy = FD->getType().getTypePtr(); 4682 4683 if (!FD->isAnonymousStructOrUnion()) { 4684 // Remember all fields written by the user. 4685 RecFields.push_back(FD); 4686 } 4687 4688 // If the field is already invalid for some reason, don't emit more 4689 // diagnostics about it. 4690 if (FD->isInvalidDecl()) 4691 continue; 4692 4693 // C99 6.7.2.1p2: 4694 // A structure or union shall not contain a member with 4695 // incomplete or function type (hence, a structure shall not 4696 // contain an instance of itself, but may contain a pointer to 4697 // an instance of itself), except that the last member of a 4698 // structure with more than one named member may have incomplete 4699 // array type; such a structure (and any union containing, 4700 // possibly recursively, a member that is such a structure) 4701 // shall not be a member of a structure or an element of an 4702 // array. 4703 if (FDTy->isFunctionType()) { 4704 // Field declared as a function. 4705 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4706 << FD->getDeclName(); 4707 FD->setInvalidDecl(); 4708 EnclosingDecl->setInvalidDecl(); 4709 continue; 4710 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4711 Record && Record->isStruct()) { 4712 // Flexible array member. 4713 if (NumNamedMembers < 1) { 4714 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4715 << FD->getDeclName(); 4716 FD->setInvalidDecl(); 4717 EnclosingDecl->setInvalidDecl(); 4718 continue; 4719 } 4720 // Okay, we have a legal flexible array member at the end of the struct. 4721 if (Record) 4722 Record->setHasFlexibleArrayMember(true); 4723 } else if (!FDTy->isDependentType() && 4724 RequireCompleteType(FD->getLocation(), FD->getType(), 4725 diag::err_field_incomplete)) { 4726 // Incomplete type 4727 FD->setInvalidDecl(); 4728 EnclosingDecl->setInvalidDecl(); 4729 continue; 4730 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4731 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4732 // If this is a member of a union, then entire union becomes "flexible". 4733 if (Record && Record->isUnion()) { 4734 Record->setHasFlexibleArrayMember(true); 4735 } else { 4736 // If this is a struct/class and this is not the last element, reject 4737 // it. Note that GCC supports variable sized arrays in the middle of 4738 // structures. 4739 if (i != NumFields-1) 4740 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4741 << FD->getDeclName() << FD->getType(); 4742 else { 4743 // We support flexible arrays at the end of structs in 4744 // other structs as an extension. 4745 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4746 << FD->getDeclName(); 4747 if (Record) 4748 Record->setHasFlexibleArrayMember(true); 4749 } 4750 } 4751 } 4752 if (Record && FDTTy->getDecl()->hasObjectMember()) 4753 Record->setHasObjectMember(true); 4754 } else if (FDTy->isObjCInterfaceType()) { 4755 /// A field cannot be an Objective-c object 4756 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4757 FD->setInvalidDecl(); 4758 EnclosingDecl->setInvalidDecl(); 4759 continue; 4760 } 4761 else if (getLangOptions().ObjC1 && 4762 getLangOptions().getGCMode() != LangOptions::NonGC && 4763 Record && 4764 (FD->getType()->isObjCObjectPointerType() || 4765 FD->getType().isObjCGCStrong())) 4766 Record->setHasObjectMember(true); 4767 // Keep track of the number of named members. 4768 if (FD->getIdentifier()) 4769 ++NumNamedMembers; 4770 } 4771 4772 // Okay, we successfully defined 'Record'. 4773 if (Record) { 4774 Record->completeDefinition(Context); 4775 } else { 4776 ObjCIvarDecl **ClsFields = 4777 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4778 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4779 ID->setIVarList(ClsFields, RecFields.size(), Context); 4780 ID->setLocEnd(RBrac); 4781 // Add ivar's to class's DeclContext. 4782 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4783 ClsFields[i]->setLexicalDeclContext(ID); 4784 ID->addDecl(ClsFields[i]); 4785 } 4786 // Must enforce the rule that ivars in the base classes may not be 4787 // duplicates. 4788 if (ID->getSuperClass()) { 4789 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4790 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4791 ObjCIvarDecl* Ivar = (*IVI); 4792 4793 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4794 ObjCIvarDecl* prevIvar = 4795 ID->getSuperClass()->lookupInstanceVariable(II); 4796 if (prevIvar) { 4797 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4798 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4799 } 4800 } 4801 } 4802 } 4803 } else if (ObjCImplementationDecl *IMPDecl = 4804 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4805 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4806 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4807 // Ivar declared in @implementation never belongs to the implementation. 4808 // Only it is in implementation's lexical context. 4809 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4810 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4811 } 4812 } 4813 4814 if (Attr) 4815 ProcessDeclAttributeList(S, Record, Attr); 4816} 4817 4818EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4819 EnumConstantDecl *LastEnumConst, 4820 SourceLocation IdLoc, 4821 IdentifierInfo *Id, 4822 ExprArg val) { 4823 Expr *Val = (Expr *)val.get(); 4824 4825 llvm::APSInt EnumVal(32); 4826 QualType EltTy; 4827 if (Val && !Val->isTypeDependent()) { 4828 // Make sure to promote the operand type to int. 4829 UsualUnaryConversions(Val); 4830 if (Val != val.get()) { 4831 val.release(); 4832 val = Val; 4833 } 4834 4835 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4836 SourceLocation ExpLoc; 4837 if (!Val->isValueDependent() && 4838 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4839 Val = 0; 4840 } else { 4841 EltTy = Val->getType(); 4842 } 4843 } 4844 4845 if (!Val) { 4846 if (LastEnumConst) { 4847 // Assign the last value + 1. 4848 EnumVal = LastEnumConst->getInitVal(); 4849 ++EnumVal; 4850 4851 // Check for overflow on increment. 4852 if (EnumVal < LastEnumConst->getInitVal()) 4853 Diag(IdLoc, diag::warn_enum_value_overflow); 4854 4855 EltTy = LastEnumConst->getType(); 4856 } else { 4857 // First value, set to zero. 4858 EltTy = Context.IntTy; 4859 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4860 } 4861 } 4862 4863 val.release(); 4864 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4865 Val, EnumVal); 4866} 4867 4868 4869Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4870 DeclPtrTy lastEnumConst, 4871 SourceLocation IdLoc, 4872 IdentifierInfo *Id, 4873 SourceLocation EqualLoc, ExprTy *val) { 4874 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4875 EnumConstantDecl *LastEnumConst = 4876 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4877 Expr *Val = static_cast<Expr*>(val); 4878 4879 // The scope passed in may not be a decl scope. Zip up the scope tree until 4880 // we find one that is. 4881 S = getNonFieldDeclScope(S); 4882 4883 // Verify that there isn't already something declared with this name in this 4884 // scope. 4885 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4886 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4887 // Maybe we will complain about the shadowed template parameter. 4888 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4889 // Just pretend that we didn't see the previous declaration. 4890 PrevDecl = 0; 4891 } 4892 4893 if (PrevDecl) { 4894 // When in C++, we may get a TagDecl with the same name; in this case the 4895 // enum constant will 'hide' the tag. 4896 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4897 "Received TagDecl when not in C++!"); 4898 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4899 if (isa<EnumConstantDecl>(PrevDecl)) 4900 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4901 else 4902 Diag(IdLoc, diag::err_redefinition) << Id; 4903 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4904 if (Val) Val->Destroy(Context); 4905 return DeclPtrTy(); 4906 } 4907 } 4908 4909 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4910 IdLoc, Id, Owned(Val)); 4911 4912 // Register this decl in the current scope stack. 4913 if (New) 4914 PushOnScopeChains(New, S); 4915 4916 return DeclPtrTy::make(New); 4917} 4918 4919void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4920 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4921 DeclPtrTy *Elements, unsigned NumElements) { 4922 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4923 QualType EnumType = Context.getTypeDeclType(Enum); 4924 4925 // TODO: If the result value doesn't fit in an int, it must be a long or long 4926 // long value. ISO C does not support this, but GCC does as an extension, 4927 // emit a warning. 4928 unsigned IntWidth = Context.Target.getIntWidth(); 4929 4930 // Verify that all the values are okay, compute the size of the values, and 4931 // reverse the list. 4932 unsigned NumNegativeBits = 0; 4933 unsigned NumPositiveBits = 0; 4934 4935 // Keep track of whether all elements have type int. 4936 bool AllElementsInt = true; 4937 4938 for (unsigned i = 0; i != NumElements; ++i) { 4939 EnumConstantDecl *ECD = 4940 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4941 if (!ECD) continue; // Already issued a diagnostic. 4942 4943 // If the enum value doesn't fit in an int, emit an extension warning. 4944 const llvm::APSInt &InitVal = ECD->getInitVal(); 4945 assert(InitVal.getBitWidth() >= IntWidth && 4946 "Should have promoted value to int"); 4947 if (InitVal.getBitWidth() > IntWidth) { 4948 llvm::APSInt V(InitVal); 4949 V.trunc(IntWidth); 4950 V.extend(InitVal.getBitWidth()); 4951 if (V != InitVal) 4952 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4953 << InitVal.toString(10); 4954 } 4955 4956 // Keep track of the size of positive and negative values. 4957 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4958 NumPositiveBits = std::max(NumPositiveBits, 4959 (unsigned)InitVal.getActiveBits()); 4960 else 4961 NumNegativeBits = std::max(NumNegativeBits, 4962 (unsigned)InitVal.getMinSignedBits()); 4963 4964 // Keep track of whether every enum element has type int (very commmon). 4965 if (AllElementsInt) 4966 AllElementsInt = ECD->getType() == Context.IntTy; 4967 } 4968 4969 // Figure out the type that should be used for this enum. 4970 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4971 QualType BestType; 4972 unsigned BestWidth; 4973 4974 if (NumNegativeBits) { 4975 // If there is a negative value, figure out the smallest integer type (of 4976 // int/long/longlong) that fits. 4977 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4978 BestType = Context.IntTy; 4979 BestWidth = IntWidth; 4980 } else { 4981 BestWidth = Context.Target.getLongWidth(); 4982 4983 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4984 BestType = Context.LongTy; 4985 else { 4986 BestWidth = Context.Target.getLongLongWidth(); 4987 4988 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4989 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4990 BestType = Context.LongLongTy; 4991 } 4992 } 4993 } else { 4994 // If there is no negative value, figure out which of uint, ulong, ulonglong 4995 // fits. 4996 if (NumPositiveBits <= IntWidth) { 4997 BestType = Context.UnsignedIntTy; 4998 BestWidth = IntWidth; 4999 } else if (NumPositiveBits <= 5000 (BestWidth = Context.Target.getLongWidth())) { 5001 BestType = Context.UnsignedLongTy; 5002 } else { 5003 BestWidth = Context.Target.getLongLongWidth(); 5004 assert(NumPositiveBits <= BestWidth && 5005 "How could an initializer get larger than ULL?"); 5006 BestType = Context.UnsignedLongLongTy; 5007 } 5008 } 5009 5010 // Loop over all of the enumerator constants, changing their types to match 5011 // the type of the enum if needed. 5012 for (unsigned i = 0; i != NumElements; ++i) { 5013 EnumConstantDecl *ECD = 5014 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5015 if (!ECD) continue; // Already issued a diagnostic. 5016 5017 // Standard C says the enumerators have int type, but we allow, as an 5018 // extension, the enumerators to be larger than int size. If each 5019 // enumerator value fits in an int, type it as an int, otherwise type it the 5020 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5021 // that X has type 'int', not 'unsigned'. 5022 if (ECD->getType() == Context.IntTy) { 5023 // Make sure the init value is signed. 5024 llvm::APSInt IV = ECD->getInitVal(); 5025 IV.setIsSigned(true); 5026 ECD->setInitVal(IV); 5027 5028 if (getLangOptions().CPlusPlus) 5029 // C++ [dcl.enum]p4: Following the closing brace of an 5030 // enum-specifier, each enumerator has the type of its 5031 // enumeration. 5032 ECD->setType(EnumType); 5033 continue; // Already int type. 5034 } 5035 5036 // Determine whether the value fits into an int. 5037 llvm::APSInt InitVal = ECD->getInitVal(); 5038 bool FitsInInt; 5039 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5040 FitsInInt = InitVal.getActiveBits() < IntWidth; 5041 else 5042 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5043 5044 // If it fits into an integer type, force it. Otherwise force it to match 5045 // the enum decl type. 5046 QualType NewTy; 5047 unsigned NewWidth; 5048 bool NewSign; 5049 if (FitsInInt) { 5050 NewTy = Context.IntTy; 5051 NewWidth = IntWidth; 5052 NewSign = true; 5053 } else if (ECD->getType() == BestType) { 5054 // Already the right type! 5055 if (getLangOptions().CPlusPlus) 5056 // C++ [dcl.enum]p4: Following the closing brace of an 5057 // enum-specifier, each enumerator has the type of its 5058 // enumeration. 5059 ECD->setType(EnumType); 5060 continue; 5061 } else { 5062 NewTy = BestType; 5063 NewWidth = BestWidth; 5064 NewSign = BestType->isSignedIntegerType(); 5065 } 5066 5067 // Adjust the APSInt value. 5068 InitVal.extOrTrunc(NewWidth); 5069 InitVal.setIsSigned(NewSign); 5070 ECD->setInitVal(InitVal); 5071 5072 // Adjust the Expr initializer and type. 5073 if (ECD->getInitExpr()) 5074 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 5075 /*isLvalue=*/false)); 5076 if (getLangOptions().CPlusPlus) 5077 // C++ [dcl.enum]p4: Following the closing brace of an 5078 // enum-specifier, each enumerator has the type of its 5079 // enumeration. 5080 ECD->setType(EnumType); 5081 else 5082 ECD->setType(NewTy); 5083 } 5084 5085 Enum->completeDefinition(Context, BestType); 5086} 5087 5088Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5089 ExprArg expr) { 5090 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5091 5092 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5093 Loc, AsmString); 5094 CurContext->addDecl(New); 5095 return DeclPtrTy::make(New); 5096} 5097 5098void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5099 SourceLocation PragmaLoc, 5100 SourceLocation NameLoc) { 5101 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5102 5103 // FIXME: This implementation is an ugly hack! 5104 if (PrevDecl) { 5105 PrevDecl->addAttr(::new (Context) WeakAttr()); 5106 return; 5107 } 5108 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 5109 return; 5110} 5111 5112void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5113 IdentifierInfo* AliasName, 5114 SourceLocation PragmaLoc, 5115 SourceLocation NameLoc, 5116 SourceLocation AliasNameLoc) { 5117 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 5118 5119 // FIXME: This implementation is an ugly hack! 5120 if (PrevDecl) { 5121 PrevDecl->addAttr(::new (Context) AliasAttr(AliasName->getName())); 5122 PrevDecl->addAttr(::new (Context) WeakAttr()); 5123 return; 5124 } 5125 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 5126 return; 5127} 5128