SemaDecl.cpp revision 930d8b5ecc074cca01ecd9a522a55f55f3b72396
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/TargetInfo.h" 22#include "clang/Basic/SourceManager.h" 23// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 24#include "clang/Lex/Preprocessor.h" 25#include "clang/Lex/HeaderSearch.h" 26#include "llvm/ADT/SmallSet.h" 27#include "llvm/ADT/STLExtras.h" 28#include <algorithm> 29#include <functional> 30 31using namespace clang; 32 33Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, Scope *S, 34 const CXXScopeSpec *SS) { 35 Decl *IIDecl = 0; 36 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, false); 37 switch (Result.getKind()) { 38 case LookupResult::NotFound: 39 case LookupResult::FoundOverloaded: 40 case LookupResult::AmbiguousBaseSubobjectTypes: 41 case LookupResult::AmbiguousBaseSubobjects: 42 // FIXME: In the event of an ambiguous lookup, we could visit all of 43 // the entities found to determine whether they are all types. This 44 // might provide better diagnostics. 45 return 0; 46 case LookupResult::Found: 47 IIDecl = Result.getAsDecl(); 48 break; 49 } 50 51 if (IIDecl) { 52 if (isa<TypedefDecl>(IIDecl) || 53 isa<ObjCInterfaceDecl>(IIDecl) || 54 isa<TagDecl>(IIDecl) || 55 isa<TemplateTypeParmDecl>(IIDecl)) 56 return IIDecl; 57 } 58 return 0; 59} 60 61DeclContext *Sema::getContainingDC(DeclContext *DC) { 62 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 63 // A C++ out-of-line method will return to the file declaration context. 64 if (MD->isOutOfLineDefinition()) 65 return MD->getLexicalDeclContext(); 66 67 // A C++ inline method is parsed *after* the topmost class it was declared in 68 // is fully parsed (it's "complete"). 69 // The parsing of a C++ inline method happens at the declaration context of 70 // the topmost (non-nested) class it is lexically declared in. 71 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 72 DC = MD->getParent(); 73 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 74 DC = RD; 75 76 // Return the declaration context of the topmost class the inline method is 77 // declared in. 78 return DC; 79 } 80 81 if (isa<ObjCMethodDecl>(DC)) 82 return Context.getTranslationUnitDecl(); 83 84 if (Decl *D = dyn_cast<Decl>(DC)) 85 return D->getLexicalDeclContext(); 86 87 return DC->getLexicalParent(); 88} 89 90void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 91 assert(getContainingDC(DC) == CurContext && 92 "The next DeclContext should be lexically contained in the current one."); 93 CurContext = DC; 94 S->setEntity(DC); 95} 96 97void Sema::PopDeclContext() { 98 assert(CurContext && "DeclContext imbalance!"); 99 100 CurContext = getContainingDC(CurContext); 101} 102 103/// Add this decl to the scope shadowed decl chains. 104void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 105 // Move up the scope chain until we find the nearest enclosing 106 // non-transparent context. The declaration will be introduced into this 107 // scope. 108 while (S->getEntity() && 109 ((DeclContext *)S->getEntity())->isTransparentContext()) 110 S = S->getParent(); 111 112 S->AddDecl(D); 113 114 // Add scoped declarations into their context, so that they can be 115 // found later. Declarations without a context won't be inserted 116 // into any context. 117 CurContext->addDecl(D); 118 119 // C++ [basic.scope]p4: 120 // -- exactly one declaration shall declare a class name or 121 // enumeration name that is not a typedef name and the other 122 // declarations shall all refer to the same object or 123 // enumerator, or all refer to functions and function templates; 124 // in this case the class name or enumeration name is hidden. 125 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 126 // We are pushing the name of a tag (enum or class). 127 if (CurContext->getLookupContext() 128 == TD->getDeclContext()->getLookupContext()) { 129 // We're pushing the tag into the current context, which might 130 // require some reshuffling in the identifier resolver. 131 IdentifierResolver::iterator 132 I = IdResolver.begin(TD->getDeclName()), 133 IEnd = IdResolver.end(); 134 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 135 NamedDecl *PrevDecl = *I; 136 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 137 PrevDecl = *I, ++I) { 138 if (TD->declarationReplaces(*I)) { 139 // This is a redeclaration. Remove it from the chain and 140 // break out, so that we'll add in the shadowed 141 // declaration. 142 S->RemoveDecl(*I); 143 if (PrevDecl == *I) { 144 IdResolver.RemoveDecl(*I); 145 IdResolver.AddDecl(TD); 146 return; 147 } else { 148 IdResolver.RemoveDecl(*I); 149 break; 150 } 151 } 152 } 153 154 // There is already a declaration with the same name in the same 155 // scope, which is not a tag declaration. It must be found 156 // before we find the new declaration, so insert the new 157 // declaration at the end of the chain. 158 IdResolver.AddShadowedDecl(TD, PrevDecl); 159 160 return; 161 } 162 } 163 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 164 // We are pushing the name of a function, which might be an 165 // overloaded name. 166 FunctionDecl *FD = cast<FunctionDecl>(D); 167 IdentifierResolver::iterator Redecl 168 = std::find_if(IdResolver.begin(FD->getDeclName()), 169 IdResolver.end(), 170 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 171 FD)); 172 if (Redecl != IdResolver.end()) { 173 // There is already a declaration of a function on our 174 // IdResolver chain. Replace it with this declaration. 175 S->RemoveDecl(*Redecl); 176 IdResolver.RemoveDecl(*Redecl); 177 } 178 } 179 180 IdResolver.AddDecl(D); 181} 182 183void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 184 if (S->decl_empty()) return; 185 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 186 "Scope shouldn't contain decls!"); 187 188 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 189 I != E; ++I) { 190 Decl *TmpD = static_cast<Decl*>(*I); 191 assert(TmpD && "This decl didn't get pushed??"); 192 193 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 194 NamedDecl *D = cast<NamedDecl>(TmpD); 195 196 if (!D->getDeclName()) continue; 197 198 // Remove this name from our lexical scope. 199 IdResolver.RemoveDecl(D); 200 } 201} 202 203/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 204/// return 0 if one not found. 205ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 206 // The third "scope" argument is 0 since we aren't enabling lazy built-in 207 // creation from this context. 208 Decl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 209 210 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 211} 212 213/// getNonFieldDeclScope - Retrieves the innermost scope, starting 214/// from S, where a non-field would be declared. This routine copes 215/// with the difference between C and C++ scoping rules in structs and 216/// unions. For example, the following code is well-formed in C but 217/// ill-formed in C++: 218/// @code 219/// struct S6 { 220/// enum { BAR } e; 221/// }; 222/// 223/// void test_S6() { 224/// struct S6 a; 225/// a.e = BAR; 226/// } 227/// @endcode 228/// For the declaration of BAR, this routine will return a different 229/// scope. The scope S will be the scope of the unnamed enumeration 230/// within S6. In C++, this routine will return the scope associated 231/// with S6, because the enumeration's scope is a transparent 232/// context but structures can contain non-field names. In C, this 233/// routine will return the translation unit scope, since the 234/// enumeration's scope is a transparent context and structures cannot 235/// contain non-field names. 236Scope *Sema::getNonFieldDeclScope(Scope *S) { 237 while (((S->getFlags() & Scope::DeclScope) == 0) || 238 (S->getEntity() && 239 ((DeclContext *)S->getEntity())->isTransparentContext()) || 240 (S->isClassScope() && !getLangOptions().CPlusPlus)) 241 S = S->getParent(); 242 return S; 243} 244 245void Sema::InitBuiltinVaListType() { 246 if (!Context.getBuiltinVaListType().isNull()) 247 return; 248 249 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 250 Decl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 251 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 252 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 253} 254 255/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 256/// lazily create a decl for it. 257NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 258 Scope *S) { 259 Builtin::ID BID = (Builtin::ID)bid; 260 261 if (Context.BuiltinInfo.hasVAListUse(BID)) 262 InitBuiltinVaListType(); 263 264 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 265 FunctionDecl *New = FunctionDecl::Create(Context, 266 Context.getTranslationUnitDecl(), 267 SourceLocation(), II, R, 268 FunctionDecl::Extern, false); 269 270 // Create Decl objects for each parameter, adding them to the 271 // FunctionDecl. 272 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 273 llvm::SmallVector<ParmVarDecl*, 16> Params; 274 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 275 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 276 FT->getArgType(i), VarDecl::None, 0)); 277 New->setParams(Context, &Params[0], Params.size()); 278 } 279 280 281 282 // TUScope is the translation-unit scope to insert this function into. 283 // FIXME: This is hideous. We need to teach PushOnScopeChains to 284 // relate Scopes to DeclContexts, and probably eliminate CurContext 285 // entirely, but we're not there yet. 286 DeclContext *SavedContext = CurContext; 287 CurContext = Context.getTranslationUnitDecl(); 288 PushOnScopeChains(New, TUScope); 289 CurContext = SavedContext; 290 return New; 291} 292 293/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 294/// everything from the standard library is defined. 295NamespaceDecl *Sema::GetStdNamespace() { 296 if (!StdNamespace) { 297 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 298 DeclContext *Global = Context.getTranslationUnitDecl(); 299 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 300 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 301 } 302 return StdNamespace; 303} 304 305/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 306/// and scope as a previous declaration 'Old'. Figure out how to resolve this 307/// situation, merging decls or emitting diagnostics as appropriate. 308/// 309TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 310 bool objc_types = false; 311 // Allow multiple definitions for ObjC built-in typedefs. 312 // FIXME: Verify the underlying types are equivalent! 313 if (getLangOptions().ObjC1) { 314 const IdentifierInfo *TypeID = New->getIdentifier(); 315 switch (TypeID->getLength()) { 316 default: break; 317 case 2: 318 if (!TypeID->isStr("id")) 319 break; 320 Context.setObjCIdType(New); 321 objc_types = true; 322 break; 323 case 5: 324 if (!TypeID->isStr("Class")) 325 break; 326 Context.setObjCClassType(New); 327 objc_types = true; 328 return New; 329 case 3: 330 if (!TypeID->isStr("SEL")) 331 break; 332 Context.setObjCSelType(New); 333 objc_types = true; 334 return New; 335 case 8: 336 if (!TypeID->isStr("Protocol")) 337 break; 338 Context.setObjCProtoType(New->getUnderlyingType()); 339 objc_types = true; 340 return New; 341 } 342 // Fall through - the typedef name was not a builtin type. 343 } 344 // Verify the old decl was also a type. 345 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 346 if (!Old) { 347 Diag(New->getLocation(), diag::err_redefinition_different_kind) 348 << New->getDeclName(); 349 if (!objc_types) 350 Diag(OldD->getLocation(), diag::note_previous_definition); 351 return New; 352 } 353 354 // Determine the "old" type we'll use for checking and diagnostics. 355 QualType OldType; 356 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 357 OldType = OldTypedef->getUnderlyingType(); 358 else 359 OldType = Context.getTypeDeclType(Old); 360 361 // If the typedef types are not identical, reject them in all languages and 362 // with any extensions enabled. 363 364 if (OldType != New->getUnderlyingType() && 365 Context.getCanonicalType(OldType) != 366 Context.getCanonicalType(New->getUnderlyingType())) { 367 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 368 << New->getUnderlyingType() << OldType; 369 if (!objc_types) 370 Diag(Old->getLocation(), diag::note_previous_definition); 371 return New; 372 } 373 if (objc_types) return New; 374 if (getLangOptions().Microsoft) return New; 375 376 // C++ [dcl.typedef]p2: 377 // In a given non-class scope, a typedef specifier can be used to 378 // redefine the name of any type declared in that scope to refer 379 // to the type to which it already refers. 380 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 381 return New; 382 383 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 384 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 385 // *either* declaration is in a system header. The code below implements 386 // this adhoc compatibility rule. FIXME: The following code will not 387 // work properly when compiling ".i" files (containing preprocessed output). 388 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 389 SourceManager &SrcMgr = Context.getSourceManager(); 390 if (SrcMgr.isInSystemHeader(Old->getLocation())) 391 return New; 392 if (SrcMgr.isInSystemHeader(New->getLocation())) 393 return New; 394 } 395 396 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 397 Diag(Old->getLocation(), diag::note_previous_definition); 398 return New; 399} 400 401/// DeclhasAttr - returns true if decl Declaration already has the target 402/// attribute. 403static bool DeclHasAttr(const Decl *decl, const Attr *target) { 404 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 405 if (attr->getKind() == target->getKind()) 406 return true; 407 408 return false; 409} 410 411/// MergeAttributes - append attributes from the Old decl to the New one. 412static void MergeAttributes(Decl *New, Decl *Old) { 413 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 414 415 while (attr) { 416 tmp = attr; 417 attr = attr->getNext(); 418 419 if (!DeclHasAttr(New, tmp)) { 420 tmp->setInherited(true); 421 New->addAttr(tmp); 422 } else { 423 tmp->setNext(0); 424 delete(tmp); 425 } 426 } 427 428 Old->invalidateAttrs(); 429} 430 431/// MergeFunctionDecl - We just parsed a function 'New' from 432/// declarator D which has the same name and scope as a previous 433/// declaration 'Old'. Figure out how to resolve this situation, 434/// merging decls or emitting diagnostics as appropriate. 435/// Redeclaration will be set true if this New is a redeclaration OldD. 436/// 437/// In C++, New and Old must be declarations that are not 438/// overloaded. Use IsOverload to determine whether New and Old are 439/// overloaded, and to select the Old declaration that New should be 440/// merged with. 441FunctionDecl * 442Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 443 assert(!isa<OverloadedFunctionDecl>(OldD) && 444 "Cannot merge with an overloaded function declaration"); 445 446 Redeclaration = false; 447 // Verify the old decl was also a function. 448 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 449 if (!Old) { 450 Diag(New->getLocation(), diag::err_redefinition_different_kind) 451 << New->getDeclName(); 452 Diag(OldD->getLocation(), diag::note_previous_definition); 453 return New; 454 } 455 456 // Determine whether the previous declaration was a definition, 457 // implicit declaration, or a declaration. 458 diag::kind PrevDiag; 459 if (Old->isThisDeclarationADefinition()) 460 PrevDiag = diag::note_previous_definition; 461 else if (Old->isImplicit()) 462 PrevDiag = diag::note_previous_implicit_declaration; 463 else 464 PrevDiag = diag::note_previous_declaration; 465 466 QualType OldQType = Context.getCanonicalType(Old->getType()); 467 QualType NewQType = Context.getCanonicalType(New->getType()); 468 469 if (getLangOptions().CPlusPlus) { 470 // (C++98 13.1p2): 471 // Certain function declarations cannot be overloaded: 472 // -- Function declarations that differ only in the return type 473 // cannot be overloaded. 474 QualType OldReturnType 475 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 476 QualType NewReturnType 477 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 478 if (OldReturnType != NewReturnType) { 479 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 480 Diag(Old->getLocation(), PrevDiag); 481 Redeclaration = true; 482 return New; 483 } 484 485 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 486 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 487 if (OldMethod && NewMethod) { 488 // -- Member function declarations with the same name and the 489 // same parameter types cannot be overloaded if any of them 490 // is a static member function declaration. 491 if (OldMethod->isStatic() || NewMethod->isStatic()) { 492 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 493 Diag(Old->getLocation(), PrevDiag); 494 return New; 495 } 496 497 // C++ [class.mem]p1: 498 // [...] A member shall not be declared twice in the 499 // member-specification, except that a nested class or member 500 // class template can be declared and then later defined. 501 if (OldMethod->getLexicalDeclContext() == 502 NewMethod->getLexicalDeclContext()) { 503 unsigned NewDiag; 504 if (isa<CXXConstructorDecl>(OldMethod)) 505 NewDiag = diag::err_constructor_redeclared; 506 else if (isa<CXXDestructorDecl>(NewMethod)) 507 NewDiag = diag::err_destructor_redeclared; 508 else if (isa<CXXConversionDecl>(NewMethod)) 509 NewDiag = diag::err_conv_function_redeclared; 510 else 511 NewDiag = diag::err_member_redeclared; 512 513 Diag(New->getLocation(), NewDiag); 514 Diag(Old->getLocation(), PrevDiag); 515 } 516 } 517 518 // (C++98 8.3.5p3): 519 // All declarations for a function shall agree exactly in both the 520 // return type and the parameter-type-list. 521 if (OldQType == NewQType) { 522 // We have a redeclaration. 523 MergeAttributes(New, Old); 524 Redeclaration = true; 525 return MergeCXXFunctionDecl(New, Old); 526 } 527 528 // Fall through for conflicting redeclarations and redefinitions. 529 } 530 531 // C: Function types need to be compatible, not identical. This handles 532 // duplicate function decls like "void f(int); void f(enum X);" properly. 533 if (!getLangOptions().CPlusPlus && 534 Context.typesAreCompatible(OldQType, NewQType)) { 535 MergeAttributes(New, Old); 536 Redeclaration = true; 537 return New; 538 } 539 540 // A function that has already been declared has been redeclared or defined 541 // with a different type- show appropriate diagnostic 542 543 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 544 // TODO: This is totally simplistic. It should handle merging functions 545 // together etc, merging extern int X; int X; ... 546 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 547 Diag(Old->getLocation(), PrevDiag); 548 return New; 549} 550 551/// Predicate for C "tentative" external object definitions (C99 6.9.2). 552static bool isTentativeDefinition(VarDecl *VD) { 553 if (VD->isFileVarDecl()) 554 return (!VD->getInit() && 555 (VD->getStorageClass() == VarDecl::None || 556 VD->getStorageClass() == VarDecl::Static)); 557 return false; 558} 559 560/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 561/// when dealing with C "tentative" external object definitions (C99 6.9.2). 562void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 563 bool VDIsTentative = isTentativeDefinition(VD); 564 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 565 566 // FIXME: I don't think this will actually see all of the 567 // redefinitions. Can't we check this property on-the-fly? 568 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 569 E = IdResolver.end(); 570 I != E; ++I) { 571 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 572 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 573 574 // Handle the following case: 575 // int a[10]; 576 // int a[]; - the code below makes sure we set the correct type. 577 // int a[11]; - this is an error, size isn't 10. 578 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 579 OldDecl->getType()->isConstantArrayType()) 580 VD->setType(OldDecl->getType()); 581 582 // Check for "tentative" definitions. We can't accomplish this in 583 // MergeVarDecl since the initializer hasn't been attached. 584 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 585 continue; 586 587 // Handle __private_extern__ just like extern. 588 if (OldDecl->getStorageClass() != VarDecl::Extern && 589 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 590 VD->getStorageClass() != VarDecl::Extern && 591 VD->getStorageClass() != VarDecl::PrivateExtern) { 592 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 593 Diag(OldDecl->getLocation(), diag::note_previous_definition); 594 } 595 } 596 } 597} 598 599/// MergeVarDecl - We just parsed a variable 'New' which has the same name 600/// and scope as a previous declaration 'Old'. Figure out how to resolve this 601/// situation, merging decls or emitting diagnostics as appropriate. 602/// 603/// Tentative definition rules (C99 6.9.2p2) are checked by 604/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 605/// definitions here, since the initializer hasn't been attached. 606/// 607VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 608 // Verify the old decl was also a variable. 609 VarDecl *Old = dyn_cast<VarDecl>(OldD); 610 if (!Old) { 611 Diag(New->getLocation(), diag::err_redefinition_different_kind) 612 << New->getDeclName(); 613 Diag(OldD->getLocation(), diag::note_previous_definition); 614 return New; 615 } 616 617 MergeAttributes(New, Old); 618 619 // Merge the types 620 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 621 if (MergedT.isNull()) { 622 Diag(New->getLocation(), diag::err_redefinition_different_type) 623 << New->getDeclName(); 624 Diag(Old->getLocation(), diag::note_previous_definition); 625 return New; 626 } 627 New->setType(MergedT); 628 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 629 if (New->getStorageClass() == VarDecl::Static && 630 (Old->getStorageClass() == VarDecl::None || 631 Old->getStorageClass() == VarDecl::Extern)) { 632 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 633 Diag(Old->getLocation(), diag::note_previous_definition); 634 return New; 635 } 636 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 637 if (New->getStorageClass() != VarDecl::Static && 638 Old->getStorageClass() == VarDecl::Static) { 639 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 640 Diag(Old->getLocation(), diag::note_previous_definition); 641 return New; 642 } 643 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 644 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 645 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 646 Diag(Old->getLocation(), diag::note_previous_definition); 647 } 648 return New; 649} 650 651/// CheckParmsForFunctionDef - Check that the parameters of the given 652/// function are appropriate for the definition of a function. This 653/// takes care of any checks that cannot be performed on the 654/// declaration itself, e.g., that the types of each of the function 655/// parameters are complete. 656bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 657 bool HasInvalidParm = false; 658 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 659 ParmVarDecl *Param = FD->getParamDecl(p); 660 661 // C99 6.7.5.3p4: the parameters in a parameter type list in a 662 // function declarator that is part of a function definition of 663 // that function shall not have incomplete type. 664 if (!Param->isInvalidDecl() && 665 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 666 diag::err_typecheck_decl_incomplete_type)) { 667 Param->setInvalidDecl(); 668 HasInvalidParm = true; 669 } 670 671 // C99 6.9.1p5: If the declarator includes a parameter type list, the 672 // declaration of each parameter shall include an identifier. 673 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 674 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 675 } 676 677 return HasInvalidParm; 678} 679 680/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 681/// no declarator (e.g. "struct foo;") is parsed. 682Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 683 TagDecl *Tag 684 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 685 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 686 if (!Record->getDeclName() && Record->isDefinition() && 687 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 688 return BuildAnonymousStructOrUnion(S, DS, Record); 689 690 // Microsoft allows unnamed struct/union fields. Don't complain 691 // about them. 692 // FIXME: Should we support Microsoft's extensions in this area? 693 if (Record->getDeclName() && getLangOptions().Microsoft) 694 return Tag; 695 } 696 697 if (!DS.isMissingDeclaratorOk()) { 698 // Warn about typedefs of enums without names, since this is an 699 // extension in both Microsoft an GNU. 700 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 701 Tag && isa<EnumDecl>(Tag)) { 702 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 703 << DS.getSourceRange(); 704 return Tag; 705 } 706 707 // FIXME: This diagnostic is emitted even when various previous 708 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 709 // DeclSpec has no means of communicating this information, and the 710 // responsible parser functions are quite far apart. 711 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 712 << DS.getSourceRange(); 713 return 0; 714 } 715 716 return Tag; 717} 718 719/// InjectAnonymousStructOrUnionMembers - Inject the members of the 720/// anonymous struct or union AnonRecord into the owning context Owner 721/// and scope S. This routine will be invoked just after we realize 722/// that an unnamed union or struct is actually an anonymous union or 723/// struct, e.g., 724/// 725/// @code 726/// union { 727/// int i; 728/// float f; 729/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 730/// // f into the surrounding scope.x 731/// @endcode 732/// 733/// This routine is recursive, injecting the names of nested anonymous 734/// structs/unions into the owning context and scope as well. 735bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 736 RecordDecl *AnonRecord) { 737 bool Invalid = false; 738 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 739 FEnd = AnonRecord->field_end(); 740 F != FEnd; ++F) { 741 if ((*F)->getDeclName()) { 742 Decl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 743 LookupOrdinaryName, true); 744 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 745 // C++ [class.union]p2: 746 // The names of the members of an anonymous union shall be 747 // distinct from the names of any other entity in the 748 // scope in which the anonymous union is declared. 749 unsigned diagKind 750 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 751 : diag::err_anonymous_struct_member_redecl; 752 Diag((*F)->getLocation(), diagKind) 753 << (*F)->getDeclName(); 754 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 755 Invalid = true; 756 } else { 757 // C++ [class.union]p2: 758 // For the purpose of name lookup, after the anonymous union 759 // definition, the members of the anonymous union are 760 // considered to have been defined in the scope in which the 761 // anonymous union is declared. 762 Owner->makeDeclVisibleInContext(*F); 763 S->AddDecl(*F); 764 IdResolver.AddDecl(*F); 765 } 766 } else if (const RecordType *InnerRecordType 767 = (*F)->getType()->getAsRecordType()) { 768 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 769 if (InnerRecord->isAnonymousStructOrUnion()) 770 Invalid = Invalid || 771 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 772 } 773 } 774 775 return Invalid; 776} 777 778/// ActOnAnonymousStructOrUnion - Handle the declaration of an 779/// anonymous structure or union. Anonymous unions are a C++ feature 780/// (C++ [class.union]) and a GNU C extension; anonymous structures 781/// are a GNU C and GNU C++ extension. 782Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 783 RecordDecl *Record) { 784 DeclContext *Owner = Record->getDeclContext(); 785 786 // Diagnose whether this anonymous struct/union is an extension. 787 if (Record->isUnion() && !getLangOptions().CPlusPlus) 788 Diag(Record->getLocation(), diag::ext_anonymous_union); 789 else if (!Record->isUnion()) 790 Diag(Record->getLocation(), diag::ext_anonymous_struct); 791 792 // C and C++ require different kinds of checks for anonymous 793 // structs/unions. 794 bool Invalid = false; 795 if (getLangOptions().CPlusPlus) { 796 const char* PrevSpec = 0; 797 // C++ [class.union]p3: 798 // Anonymous unions declared in a named namespace or in the 799 // global namespace shall be declared static. 800 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 801 (isa<TranslationUnitDecl>(Owner) || 802 (isa<NamespaceDecl>(Owner) && 803 cast<NamespaceDecl>(Owner)->getDeclName()))) { 804 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 805 Invalid = true; 806 807 // Recover by adding 'static'. 808 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 809 } 810 // C++ [class.union]p3: 811 // A storage class is not allowed in a declaration of an 812 // anonymous union in a class scope. 813 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 814 isa<RecordDecl>(Owner)) { 815 Diag(DS.getStorageClassSpecLoc(), 816 diag::err_anonymous_union_with_storage_spec); 817 Invalid = true; 818 819 // Recover by removing the storage specifier. 820 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 821 PrevSpec); 822 } 823 824 // C++ [class.union]p2: 825 // The member-specification of an anonymous union shall only 826 // define non-static data members. [Note: nested types and 827 // functions cannot be declared within an anonymous union. ] 828 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 829 MemEnd = Record->decls_end(); 830 Mem != MemEnd; ++Mem) { 831 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 832 // C++ [class.union]p3: 833 // An anonymous union shall not have private or protected 834 // members (clause 11). 835 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 836 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 837 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 838 Invalid = true; 839 } 840 } else if ((*Mem)->isImplicit()) { 841 // Any implicit members are fine. 842 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 843 if (!MemRecord->isAnonymousStructOrUnion() && 844 MemRecord->getDeclName()) { 845 // This is a nested type declaration. 846 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 847 << (int)Record->isUnion(); 848 Invalid = true; 849 } 850 } else { 851 // We have something that isn't a non-static data 852 // member. Complain about it. 853 unsigned DK = diag::err_anonymous_record_bad_member; 854 if (isa<TypeDecl>(*Mem)) 855 DK = diag::err_anonymous_record_with_type; 856 else if (isa<FunctionDecl>(*Mem)) 857 DK = diag::err_anonymous_record_with_function; 858 else if (isa<VarDecl>(*Mem)) 859 DK = diag::err_anonymous_record_with_static; 860 Diag((*Mem)->getLocation(), DK) 861 << (int)Record->isUnion(); 862 Invalid = true; 863 } 864 } 865 } else { 866 // FIXME: Check GNU C semantics 867 if (Record->isUnion() && !Owner->isRecord()) { 868 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 869 << (int)getLangOptions().CPlusPlus; 870 Invalid = true; 871 } 872 } 873 874 if (!Record->isUnion() && !Owner->isRecord()) { 875 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 876 << (int)getLangOptions().CPlusPlus; 877 Invalid = true; 878 } 879 880 // Create a declaration for this anonymous struct/union. 881 NamedDecl *Anon = 0; 882 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 883 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 884 /*IdentifierInfo=*/0, 885 Context.getTypeDeclType(Record), 886 /*BitWidth=*/0, /*Mutable=*/false); 887 Anon->setAccess(AS_public); 888 if (getLangOptions().CPlusPlus) 889 FieldCollector->Add(cast<FieldDecl>(Anon)); 890 } else { 891 VarDecl::StorageClass SC; 892 switch (DS.getStorageClassSpec()) { 893 default: assert(0 && "Unknown storage class!"); 894 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 895 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 896 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 897 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 898 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 899 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 900 case DeclSpec::SCS_mutable: 901 // mutable can only appear on non-static class members, so it's always 902 // an error here 903 Diag(Record->getLocation(), diag::err_mutable_nonmember); 904 Invalid = true; 905 SC = VarDecl::None; 906 break; 907 } 908 909 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 910 /*IdentifierInfo=*/0, 911 Context.getTypeDeclType(Record), 912 SC, DS.getSourceRange().getBegin()); 913 } 914 Anon->setImplicit(); 915 916 // Add the anonymous struct/union object to the current 917 // context. We'll be referencing this object when we refer to one of 918 // its members. 919 Owner->addDecl(Anon); 920 921 // Inject the members of the anonymous struct/union into the owning 922 // context and into the identifier resolver chain for name lookup 923 // purposes. 924 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 925 Invalid = true; 926 927 // Mark this as an anonymous struct/union type. Note that we do not 928 // do this until after we have already checked and injected the 929 // members of this anonymous struct/union type, because otherwise 930 // the members could be injected twice: once by DeclContext when it 931 // builds its lookup table, and once by 932 // InjectAnonymousStructOrUnionMembers. 933 Record->setAnonymousStructOrUnion(true); 934 935 if (Invalid) 936 Anon->setInvalidDecl(); 937 938 return Anon; 939} 940 941bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 942 bool DirectInit) { 943 // Get the type before calling CheckSingleAssignmentConstraints(), since 944 // it can promote the expression. 945 QualType InitType = Init->getType(); 946 947 if (getLangOptions().CPlusPlus) { 948 // FIXME: I dislike this error message. A lot. 949 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 950 return Diag(Init->getSourceRange().getBegin(), 951 diag::err_typecheck_convert_incompatible) 952 << DeclType << Init->getType() << "initializing" 953 << Init->getSourceRange(); 954 955 return false; 956 } 957 958 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 959 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 960 InitType, Init, "initializing"); 961} 962 963bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 964 const ArrayType *AT = Context.getAsArrayType(DeclT); 965 966 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 967 // C99 6.7.8p14. We have an array of character type with unknown size 968 // being initialized to a string literal. 969 llvm::APSInt ConstVal(32); 970 ConstVal = strLiteral->getByteLength() + 1; 971 // Return a new array type (C99 6.7.8p22). 972 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 973 ArrayType::Normal, 0); 974 } else { 975 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 976 // C99 6.7.8p14. We have an array of character type with known size. 977 // FIXME: Avoid truncation for 64-bit length strings. 978 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 979 Diag(strLiteral->getSourceRange().getBegin(), 980 diag::warn_initializer_string_for_char_array_too_long) 981 << strLiteral->getSourceRange(); 982 } 983 // Set type from "char *" to "constant array of char". 984 strLiteral->setType(DeclT); 985 // For now, we always return false (meaning success). 986 return false; 987} 988 989StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 990 const ArrayType *AT = Context.getAsArrayType(DeclType); 991 if (AT && AT->getElementType()->isCharType()) { 992 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 993 } 994 return 0; 995} 996 997bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 998 SourceLocation InitLoc, 999 DeclarationName InitEntity, 1000 bool DirectInit) { 1001 if (DeclType->isDependentType() || Init->isTypeDependent()) 1002 return false; 1003 1004 // C++ [dcl.init.ref]p1: 1005 // A variable declared to be a T&, that is "reference to type T" 1006 // (8.3.2), shall be initialized by an object, or function, of 1007 // type T or by an object that can be converted into a T. 1008 if (DeclType->isReferenceType()) 1009 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1010 1011 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1012 // of unknown size ("[]") or an object type that is not a variable array type. 1013 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1014 return Diag(InitLoc, diag::err_variable_object_no_init) 1015 << VAT->getSizeExpr()->getSourceRange(); 1016 1017 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1018 if (!InitList) { 1019 // FIXME: Handle wide strings 1020 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1021 return CheckStringLiteralInit(strLiteral, DeclType); 1022 1023 // C++ [dcl.init]p14: 1024 // -- If the destination type is a (possibly cv-qualified) class 1025 // type: 1026 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1027 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1028 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1029 1030 // -- If the initialization is direct-initialization, or if it is 1031 // copy-initialization where the cv-unqualified version of the 1032 // source type is the same class as, or a derived class of, the 1033 // class of the destination, constructors are considered. 1034 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1035 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1036 CXXConstructorDecl *Constructor 1037 = PerformInitializationByConstructor(DeclType, &Init, 1, 1038 InitLoc, Init->getSourceRange(), 1039 InitEntity, 1040 DirectInit? IK_Direct : IK_Copy); 1041 return Constructor == 0; 1042 } 1043 1044 // -- Otherwise (i.e., for the remaining copy-initialization 1045 // cases), user-defined conversion sequences that can 1046 // convert from the source type to the destination type or 1047 // (when a conversion function is used) to a derived class 1048 // thereof are enumerated as described in 13.3.1.4, and the 1049 // best one is chosen through overload resolution 1050 // (13.3). If the conversion cannot be done or is 1051 // ambiguous, the initialization is ill-formed. The 1052 // function selected is called with the initializer 1053 // expression as its argument; if the function is a 1054 // constructor, the call initializes a temporary of the 1055 // destination type. 1056 // FIXME: We're pretending to do copy elision here; return to 1057 // this when we have ASTs for such things. 1058 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1059 return false; 1060 1061 if (InitEntity) 1062 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1063 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1064 << Init->getType() << Init->getSourceRange(); 1065 else 1066 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1067 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1068 << Init->getType() << Init->getSourceRange(); 1069 } 1070 1071 // C99 6.7.8p16. 1072 if (DeclType->isArrayType()) 1073 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1074 << Init->getSourceRange(); 1075 1076 return CheckSingleInitializer(Init, DeclType, DirectInit); 1077 } 1078 1079 bool hadError = CheckInitList(InitList, DeclType); 1080 Init = InitList; 1081 return hadError; 1082} 1083 1084/// GetNameForDeclarator - Determine the full declaration name for the 1085/// given Declarator. 1086DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1087 switch (D.getKind()) { 1088 case Declarator::DK_Abstract: 1089 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1090 return DeclarationName(); 1091 1092 case Declarator::DK_Normal: 1093 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1094 return DeclarationName(D.getIdentifier()); 1095 1096 case Declarator::DK_Constructor: { 1097 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1098 Ty = Context.getCanonicalType(Ty); 1099 return Context.DeclarationNames.getCXXConstructorName(Ty); 1100 } 1101 1102 case Declarator::DK_Destructor: { 1103 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1104 Ty = Context.getCanonicalType(Ty); 1105 return Context.DeclarationNames.getCXXDestructorName(Ty); 1106 } 1107 1108 case Declarator::DK_Conversion: { 1109 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1110 Ty = Context.getCanonicalType(Ty); 1111 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1112 } 1113 1114 case Declarator::DK_Operator: 1115 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1116 return Context.DeclarationNames.getCXXOperatorName( 1117 D.getOverloadedOperator()); 1118 } 1119 1120 assert(false && "Unknown name kind"); 1121 return DeclarationName(); 1122} 1123 1124/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1125/// functions Declaration and Definition are "nearly" matching. This 1126/// heuristic is used to improve diagnostics in the case where an 1127/// out-of-line member function definition doesn't match any 1128/// declaration within the class. 1129static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1130 FunctionDecl *Declaration, 1131 FunctionDecl *Definition) { 1132 if (Declaration->param_size() != Definition->param_size()) 1133 return false; 1134 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1135 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1136 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1137 1138 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1139 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1140 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1141 return false; 1142 } 1143 1144 return true; 1145} 1146 1147Sema::DeclTy * 1148Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1149 bool IsFunctionDefinition) { 1150 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1151 DeclarationName Name = GetNameForDeclarator(D); 1152 1153 // All of these full declarators require an identifier. If it doesn't have 1154 // one, the ParsedFreeStandingDeclSpec action should be used. 1155 if (!Name) { 1156 if (!D.getInvalidType()) // Reject this if we think it is valid. 1157 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1158 diag::err_declarator_need_ident) 1159 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1160 return 0; 1161 } 1162 1163 // The scope passed in may not be a decl scope. Zip up the scope tree until 1164 // we find one that is. 1165 while ((S->getFlags() & Scope::DeclScope) == 0 || 1166 (S->getFlags() & Scope::TemplateParamScope) != 0) 1167 S = S->getParent(); 1168 1169 DeclContext *DC; 1170 Decl *PrevDecl; 1171 NamedDecl *New; 1172 bool InvalidDecl = false; 1173 1174 // See if this is a redefinition of a variable in the same scope. 1175 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1176 DC = CurContext; 1177 PrevDecl = LookupName(S, Name, LookupOrdinaryName); 1178 } else { // Something like "int foo::x;" 1179 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1180 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName); 1181 1182 // C++ 7.3.1.2p2: 1183 // Members (including explicit specializations of templates) of a named 1184 // namespace can also be defined outside that namespace by explicit 1185 // qualification of the name being defined, provided that the entity being 1186 // defined was already declared in the namespace and the definition appears 1187 // after the point of declaration in a namespace that encloses the 1188 // declarations namespace. 1189 // 1190 // Note that we only check the context at this point. We don't yet 1191 // have enough information to make sure that PrevDecl is actually 1192 // the declaration we want to match. For example, given: 1193 // 1194 // class X { 1195 // void f(); 1196 // void f(float); 1197 // }; 1198 // 1199 // void X::f(int) { } // ill-formed 1200 // 1201 // In this case, PrevDecl will point to the overload set 1202 // containing the two f's declared in X, but neither of them 1203 // matches. 1204 if (!CurContext->Encloses(DC)) { 1205 // The qualifying scope doesn't enclose the original declaration. 1206 // Emit diagnostic based on current scope. 1207 SourceLocation L = D.getIdentifierLoc(); 1208 SourceRange R = D.getCXXScopeSpec().getRange(); 1209 if (isa<FunctionDecl>(CurContext)) { 1210 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1211 } else { 1212 Diag(L, diag::err_invalid_declarator_scope) 1213 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1214 } 1215 InvalidDecl = true; 1216 } 1217 } 1218 1219 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1220 // Maybe we will complain about the shadowed template parameter. 1221 InvalidDecl = InvalidDecl 1222 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1223 // Just pretend that we didn't see the previous declaration. 1224 PrevDecl = 0; 1225 } 1226 1227 // In C++, the previous declaration we find might be a tag type 1228 // (class or enum). In this case, the new declaration will hide the 1229 // tag type. Note that this does does not apply if we're declaring a 1230 // typedef (C++ [dcl.typedef]p4). 1231 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1232 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1233 PrevDecl = 0; 1234 1235 QualType R = GetTypeForDeclarator(D, S); 1236 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1237 1238 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1239 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1240 InvalidDecl); 1241 } else if (R.getTypePtr()->isFunctionType()) { 1242 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1243 IsFunctionDefinition, InvalidDecl); 1244 } else { 1245 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1246 InvalidDecl); 1247 } 1248 1249 if (New == 0) 1250 return 0; 1251 1252 // Set the lexical context. If the declarator has a C++ scope specifier, the 1253 // lexical context will be different from the semantic context. 1254 New->setLexicalDeclContext(CurContext); 1255 1256 // If this has an identifier, add it to the scope stack. 1257 if (Name) 1258 PushOnScopeChains(New, S); 1259 // If any semantic error occurred, mark the decl as invalid. 1260 if (D.getInvalidType() || InvalidDecl) 1261 New->setInvalidDecl(); 1262 1263 return New; 1264} 1265 1266NamedDecl* 1267Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1268 QualType R, Decl* LastDeclarator, 1269 Decl* PrevDecl, bool& InvalidDecl) { 1270 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1271 if (D.getCXXScopeSpec().isSet()) { 1272 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1273 << D.getCXXScopeSpec().getRange(); 1274 InvalidDecl = true; 1275 // Pretend we didn't see the scope specifier. 1276 DC = 0; 1277 } 1278 1279 // Check that there are no default arguments (C++ only). 1280 if (getLangOptions().CPlusPlus) 1281 CheckExtraCXXDefaultArguments(D); 1282 1283 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1284 if (!NewTD) return 0; 1285 1286 // Handle attributes prior to checking for duplicates in MergeVarDecl 1287 ProcessDeclAttributes(NewTD, D); 1288 // Merge the decl with the existing one if appropriate. If the decl is 1289 // in an outer scope, it isn't the same thing. 1290 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1291 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1292 if (NewTD == 0) return 0; 1293 } 1294 1295 if (S->getFnParent() == 0) { 1296 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1297 // then it shall have block scope. 1298 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1299 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1300 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1301 else 1302 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1303 1304 InvalidDecl = true; 1305 } 1306 } 1307 return NewTD; 1308} 1309 1310NamedDecl* 1311Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1312 QualType R, Decl* LastDeclarator, 1313 Decl* PrevDecl, bool& InvalidDecl) { 1314 DeclarationName Name = GetNameForDeclarator(D); 1315 1316 // Check that there are no default arguments (C++ only). 1317 if (getLangOptions().CPlusPlus) 1318 CheckExtraCXXDefaultArguments(D); 1319 1320 if (R.getTypePtr()->isObjCInterfaceType()) { 1321 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1322 << D.getIdentifier(); 1323 InvalidDecl = true; 1324 } 1325 1326 VarDecl *NewVD; 1327 VarDecl::StorageClass SC; 1328 switch (D.getDeclSpec().getStorageClassSpec()) { 1329 default: assert(0 && "Unknown storage class!"); 1330 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1331 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1332 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1333 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1334 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1335 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1336 case DeclSpec::SCS_mutable: 1337 // mutable can only appear on non-static class members, so it's always 1338 // an error here 1339 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1340 InvalidDecl = true; 1341 SC = VarDecl::None; 1342 break; 1343 } 1344 1345 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1346 if (!II) { 1347 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1348 << Name.getAsString(); 1349 return 0; 1350 } 1351 1352 if (DC->isRecord()) { 1353 // This is a static data member for a C++ class. 1354 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1355 D.getIdentifierLoc(), II, 1356 R); 1357 } else { 1358 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1359 if (S->getFnParent() == 0) { 1360 // C99 6.9p2: The storage-class specifiers auto and register shall not 1361 // appear in the declaration specifiers in an external declaration. 1362 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1363 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1364 InvalidDecl = true; 1365 } 1366 } 1367 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1368 II, R, SC, 1369 // FIXME: Move to DeclGroup... 1370 D.getDeclSpec().getSourceRange().getBegin()); 1371 NewVD->setThreadSpecified(ThreadSpecified); 1372 } 1373 NewVD->setNextDeclarator(LastDeclarator); 1374 1375 // Handle attributes prior to checking for duplicates in MergeVarDecl 1376 ProcessDeclAttributes(NewVD, D); 1377 1378 // Handle GNU asm-label extension (encoded as an attribute). 1379 if (Expr *E = (Expr*) D.getAsmLabel()) { 1380 // The parser guarantees this is a string. 1381 StringLiteral *SE = cast<StringLiteral>(E); 1382 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1383 SE->getByteLength()))); 1384 } 1385 1386 // Emit an error if an address space was applied to decl with local storage. 1387 // This includes arrays of objects with address space qualifiers, but not 1388 // automatic variables that point to other address spaces. 1389 // ISO/IEC TR 18037 S5.1.2 1390 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1391 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1392 InvalidDecl = true; 1393 } 1394 // Merge the decl with the existing one if appropriate. If the decl is 1395 // in an outer scope, it isn't the same thing. 1396 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1397 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1398 // The user tried to define a non-static data member 1399 // out-of-line (C++ [dcl.meaning]p1). 1400 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1401 << D.getCXXScopeSpec().getRange(); 1402 NewVD->Destroy(Context); 1403 return 0; 1404 } 1405 1406 NewVD = MergeVarDecl(NewVD, PrevDecl); 1407 if (NewVD == 0) return 0; 1408 1409 if (D.getCXXScopeSpec().isSet()) { 1410 // No previous declaration in the qualifying scope. 1411 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1412 << Name << D.getCXXScopeSpec().getRange(); 1413 InvalidDecl = true; 1414 } 1415 } 1416 return NewVD; 1417} 1418 1419NamedDecl* 1420Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1421 QualType R, Decl *LastDeclarator, 1422 Decl* PrevDecl, bool IsFunctionDefinition, 1423 bool& InvalidDecl) { 1424 assert(R.getTypePtr()->isFunctionType()); 1425 1426 DeclarationName Name = GetNameForDeclarator(D); 1427 FunctionDecl::StorageClass SC = FunctionDecl::None; 1428 switch (D.getDeclSpec().getStorageClassSpec()) { 1429 default: assert(0 && "Unknown storage class!"); 1430 case DeclSpec::SCS_auto: 1431 case DeclSpec::SCS_register: 1432 case DeclSpec::SCS_mutable: 1433 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1434 InvalidDecl = true; 1435 break; 1436 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1437 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1438 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1439 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1440 } 1441 1442 bool isInline = D.getDeclSpec().isInlineSpecified(); 1443 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1444 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1445 1446 FunctionDecl *NewFD; 1447 if (D.getKind() == Declarator::DK_Constructor) { 1448 // This is a C++ constructor declaration. 1449 assert(DC->isRecord() && 1450 "Constructors can only be declared in a member context"); 1451 1452 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1453 1454 // Create the new declaration 1455 NewFD = CXXConstructorDecl::Create(Context, 1456 cast<CXXRecordDecl>(DC), 1457 D.getIdentifierLoc(), Name, R, 1458 isExplicit, isInline, 1459 /*isImplicitlyDeclared=*/false); 1460 1461 if (InvalidDecl) 1462 NewFD->setInvalidDecl(); 1463 } else if (D.getKind() == Declarator::DK_Destructor) { 1464 // This is a C++ destructor declaration. 1465 if (DC->isRecord()) { 1466 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1467 1468 NewFD = CXXDestructorDecl::Create(Context, 1469 cast<CXXRecordDecl>(DC), 1470 D.getIdentifierLoc(), Name, R, 1471 isInline, 1472 /*isImplicitlyDeclared=*/false); 1473 1474 if (InvalidDecl) 1475 NewFD->setInvalidDecl(); 1476 } else { 1477 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1478 1479 // Create a FunctionDecl to satisfy the function definition parsing 1480 // code path. 1481 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1482 Name, R, SC, isInline, 1483 // FIXME: Move to DeclGroup... 1484 D.getDeclSpec().getSourceRange().getBegin()); 1485 InvalidDecl = true; 1486 NewFD->setInvalidDecl(); 1487 } 1488 } else if (D.getKind() == Declarator::DK_Conversion) { 1489 if (!DC->isRecord()) { 1490 Diag(D.getIdentifierLoc(), 1491 diag::err_conv_function_not_member); 1492 return 0; 1493 } else { 1494 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1495 1496 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1497 D.getIdentifierLoc(), Name, R, 1498 isInline, isExplicit); 1499 1500 if (InvalidDecl) 1501 NewFD->setInvalidDecl(); 1502 } 1503 } else if (DC->isRecord()) { 1504 // This is a C++ method declaration. 1505 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1506 D.getIdentifierLoc(), Name, R, 1507 (SC == FunctionDecl::Static), isInline); 1508 } else { 1509 NewFD = FunctionDecl::Create(Context, DC, 1510 D.getIdentifierLoc(), 1511 Name, R, SC, isInline, 1512 // FIXME: Move to DeclGroup... 1513 D.getDeclSpec().getSourceRange().getBegin()); 1514 } 1515 NewFD->setNextDeclarator(LastDeclarator); 1516 1517 // Set the lexical context. If the declarator has a C++ 1518 // scope specifier, the lexical context will be different 1519 // from the semantic context. 1520 NewFD->setLexicalDeclContext(CurContext); 1521 1522 // Handle GNU asm-label extension (encoded as an attribute). 1523 if (Expr *E = (Expr*) D.getAsmLabel()) { 1524 // The parser guarantees this is a string. 1525 StringLiteral *SE = cast<StringLiteral>(E); 1526 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1527 SE->getByteLength()))); 1528 } 1529 1530 // Copy the parameter declarations from the declarator D to 1531 // the function declaration NewFD, if they are available. 1532 if (D.getNumTypeObjects() > 0) { 1533 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1534 1535 // Create Decl objects for each parameter, adding them to the 1536 // FunctionDecl. 1537 llvm::SmallVector<ParmVarDecl*, 16> Params; 1538 1539 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1540 // function that takes no arguments, not a function that takes a 1541 // single void argument. 1542 // We let through "const void" here because Sema::GetTypeForDeclarator 1543 // already checks for that case. 1544 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1545 FTI.ArgInfo[0].Param && 1546 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1547 // empty arg list, don't push any params. 1548 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1549 1550 // In C++, the empty parameter-type-list must be spelled "void"; a 1551 // typedef of void is not permitted. 1552 if (getLangOptions().CPlusPlus && 1553 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1554 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1555 } 1556 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1557 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1558 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1559 } 1560 1561 NewFD->setParams(Context, &Params[0], Params.size()); 1562 } else if (R->getAsTypedefType()) { 1563 // When we're declaring a function with a typedef, as in the 1564 // following example, we'll need to synthesize (unnamed) 1565 // parameters for use in the declaration. 1566 // 1567 // @code 1568 // typedef void fn(int); 1569 // fn f; 1570 // @endcode 1571 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1572 if (!FT) { 1573 // This is a typedef of a function with no prototype, so we 1574 // don't need to do anything. 1575 } else if ((FT->getNumArgs() == 0) || 1576 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1577 FT->getArgType(0)->isVoidType())) { 1578 // This is a zero-argument function. We don't need to do anything. 1579 } else { 1580 // Synthesize a parameter for each argument type. 1581 llvm::SmallVector<ParmVarDecl*, 16> Params; 1582 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1583 ArgType != FT->arg_type_end(); ++ArgType) { 1584 Params.push_back(ParmVarDecl::Create(Context, DC, 1585 SourceLocation(), 0, 1586 *ArgType, VarDecl::None, 1587 0)); 1588 } 1589 1590 NewFD->setParams(Context, &Params[0], Params.size()); 1591 } 1592 } 1593 1594 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1595 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1596 else if (isa<CXXDestructorDecl>(NewFD)) { 1597 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1598 Record->setUserDeclaredDestructor(true); 1599 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1600 // user-defined destructor. 1601 Record->setPOD(false); 1602 } else if (CXXConversionDecl *Conversion = 1603 dyn_cast<CXXConversionDecl>(NewFD)) 1604 ActOnConversionDeclarator(Conversion); 1605 1606 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1607 if (NewFD->isOverloadedOperator() && 1608 CheckOverloadedOperatorDeclaration(NewFD)) 1609 NewFD->setInvalidDecl(); 1610 1611 // Merge the decl with the existing one if appropriate. Since C functions 1612 // are in a flat namespace, make sure we consider decls in outer scopes. 1613 if (PrevDecl && 1614 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1615 bool Redeclaration = false; 1616 1617 // If C++, determine whether NewFD is an overload of PrevDecl or 1618 // a declaration that requires merging. If it's an overload, 1619 // there's no more work to do here; we'll just add the new 1620 // function to the scope. 1621 OverloadedFunctionDecl::function_iterator MatchedDecl; 1622 if (!getLangOptions().CPlusPlus || 1623 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1624 Decl *OldDecl = PrevDecl; 1625 1626 // If PrevDecl was an overloaded function, extract the 1627 // FunctionDecl that matched. 1628 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1629 OldDecl = *MatchedDecl; 1630 1631 // NewFD and PrevDecl represent declarations that need to be 1632 // merged. 1633 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1634 1635 if (NewFD == 0) return 0; 1636 if (Redeclaration) { 1637 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1638 1639 // An out-of-line member function declaration must also be a 1640 // definition (C++ [dcl.meaning]p1). 1641 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1642 !InvalidDecl) { 1643 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1644 << D.getCXXScopeSpec().getRange(); 1645 NewFD->setInvalidDecl(); 1646 } 1647 } 1648 } 1649 1650 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1651 // The user tried to provide an out-of-line definition for a 1652 // member function, but there was no such member function 1653 // declared (C++ [class.mfct]p2). For example: 1654 // 1655 // class X { 1656 // void f() const; 1657 // }; 1658 // 1659 // void X::f() { } // ill-formed 1660 // 1661 // Complain about this problem, and attempt to suggest close 1662 // matches (e.g., those that differ only in cv-qualifiers and 1663 // whether the parameter types are references). 1664 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1665 << cast<CXXRecordDecl>(DC)->getDeclName() 1666 << D.getCXXScopeSpec().getRange(); 1667 InvalidDecl = true; 1668 1669 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName); 1670 if (!PrevDecl) { 1671 // Nothing to suggest. 1672 } else if (OverloadedFunctionDecl *Ovl 1673 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1674 for (OverloadedFunctionDecl::function_iterator 1675 Func = Ovl->function_begin(), 1676 FuncEnd = Ovl->function_end(); 1677 Func != FuncEnd; ++Func) { 1678 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1679 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1680 1681 } 1682 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1683 // Suggest this no matter how mismatched it is; it's the only 1684 // thing we have. 1685 unsigned diag; 1686 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1687 diag = diag::note_member_def_close_match; 1688 else if (Method->getBody()) 1689 diag = diag::note_previous_definition; 1690 else 1691 diag = diag::note_previous_declaration; 1692 Diag(Method->getLocation(), diag); 1693 } 1694 1695 PrevDecl = 0; 1696 } 1697 } 1698 // Handle attributes. We need to have merged decls when handling attributes 1699 // (for example to check for conflicts, etc). 1700 ProcessDeclAttributes(NewFD, D); 1701 1702 if (getLangOptions().CPlusPlus) { 1703 // In C++, check default arguments now that we have merged decls. 1704 CheckCXXDefaultArguments(NewFD); 1705 1706 // An out-of-line member function declaration must also be a 1707 // definition (C++ [dcl.meaning]p1). 1708 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1709 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1710 << D.getCXXScopeSpec().getRange(); 1711 InvalidDecl = true; 1712 } 1713 } 1714 return NewFD; 1715} 1716 1717void Sema::InitializerElementNotConstant(const Expr *Init) { 1718 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1719 << Init->getSourceRange(); 1720} 1721 1722bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1723 switch (Init->getStmtClass()) { 1724 default: 1725 InitializerElementNotConstant(Init); 1726 return true; 1727 case Expr::ParenExprClass: { 1728 const ParenExpr* PE = cast<ParenExpr>(Init); 1729 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1730 } 1731 case Expr::CompoundLiteralExprClass: 1732 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1733 case Expr::DeclRefExprClass: 1734 case Expr::QualifiedDeclRefExprClass: { 1735 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1736 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1737 if (VD->hasGlobalStorage()) 1738 return false; 1739 InitializerElementNotConstant(Init); 1740 return true; 1741 } 1742 if (isa<FunctionDecl>(D)) 1743 return false; 1744 InitializerElementNotConstant(Init); 1745 return true; 1746 } 1747 case Expr::MemberExprClass: { 1748 const MemberExpr *M = cast<MemberExpr>(Init); 1749 if (M->isArrow()) 1750 return CheckAddressConstantExpression(M->getBase()); 1751 return CheckAddressConstantExpressionLValue(M->getBase()); 1752 } 1753 case Expr::ArraySubscriptExprClass: { 1754 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1755 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1756 return CheckAddressConstantExpression(ASE->getBase()) || 1757 CheckArithmeticConstantExpression(ASE->getIdx()); 1758 } 1759 case Expr::StringLiteralClass: 1760 case Expr::PredefinedExprClass: 1761 return false; 1762 case Expr::UnaryOperatorClass: { 1763 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1764 1765 // C99 6.6p9 1766 if (Exp->getOpcode() == UnaryOperator::Deref) 1767 return CheckAddressConstantExpression(Exp->getSubExpr()); 1768 1769 InitializerElementNotConstant(Init); 1770 return true; 1771 } 1772 } 1773} 1774 1775bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1776 switch (Init->getStmtClass()) { 1777 default: 1778 InitializerElementNotConstant(Init); 1779 return true; 1780 case Expr::ParenExprClass: 1781 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1782 case Expr::StringLiteralClass: 1783 case Expr::ObjCStringLiteralClass: 1784 return false; 1785 case Expr::CallExprClass: 1786 case Expr::CXXOperatorCallExprClass: 1787 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1788 if (cast<CallExpr>(Init)->isBuiltinCall() == 1789 Builtin::BI__builtin___CFStringMakeConstantString) 1790 return false; 1791 1792 InitializerElementNotConstant(Init); 1793 return true; 1794 1795 case Expr::UnaryOperatorClass: { 1796 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1797 1798 // C99 6.6p9 1799 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1800 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1801 1802 if (Exp->getOpcode() == UnaryOperator::Extension) 1803 return CheckAddressConstantExpression(Exp->getSubExpr()); 1804 1805 InitializerElementNotConstant(Init); 1806 return true; 1807 } 1808 case Expr::BinaryOperatorClass: { 1809 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1810 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1811 1812 Expr *PExp = Exp->getLHS(); 1813 Expr *IExp = Exp->getRHS(); 1814 if (IExp->getType()->isPointerType()) 1815 std::swap(PExp, IExp); 1816 1817 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1818 return CheckAddressConstantExpression(PExp) || 1819 CheckArithmeticConstantExpression(IExp); 1820 } 1821 case Expr::ImplicitCastExprClass: 1822 case Expr::CStyleCastExprClass: { 1823 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1824 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1825 // Check for implicit promotion 1826 if (SubExpr->getType()->isFunctionType() || 1827 SubExpr->getType()->isArrayType()) 1828 return CheckAddressConstantExpressionLValue(SubExpr); 1829 } 1830 1831 // Check for pointer->pointer cast 1832 if (SubExpr->getType()->isPointerType()) 1833 return CheckAddressConstantExpression(SubExpr); 1834 1835 if (SubExpr->getType()->isIntegralType()) { 1836 // Check for the special-case of a pointer->int->pointer cast; 1837 // this isn't standard, but some code requires it. See 1838 // PR2720 for an example. 1839 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1840 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1841 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1842 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1843 if (IntWidth >= PointerWidth) { 1844 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1845 } 1846 } 1847 } 1848 } 1849 if (SubExpr->getType()->isArithmeticType()) { 1850 return CheckArithmeticConstantExpression(SubExpr); 1851 } 1852 1853 InitializerElementNotConstant(Init); 1854 return true; 1855 } 1856 case Expr::ConditionalOperatorClass: { 1857 // FIXME: Should we pedwarn here? 1858 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1859 if (!Exp->getCond()->getType()->isArithmeticType()) { 1860 InitializerElementNotConstant(Init); 1861 return true; 1862 } 1863 if (CheckArithmeticConstantExpression(Exp->getCond())) 1864 return true; 1865 if (Exp->getLHS() && 1866 CheckAddressConstantExpression(Exp->getLHS())) 1867 return true; 1868 return CheckAddressConstantExpression(Exp->getRHS()); 1869 } 1870 case Expr::AddrLabelExprClass: 1871 return false; 1872 } 1873} 1874 1875static const Expr* FindExpressionBaseAddress(const Expr* E); 1876 1877static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1878 switch (E->getStmtClass()) { 1879 default: 1880 return E; 1881 case Expr::ParenExprClass: { 1882 const ParenExpr* PE = cast<ParenExpr>(E); 1883 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1884 } 1885 case Expr::MemberExprClass: { 1886 const MemberExpr *M = cast<MemberExpr>(E); 1887 if (M->isArrow()) 1888 return FindExpressionBaseAddress(M->getBase()); 1889 return FindExpressionBaseAddressLValue(M->getBase()); 1890 } 1891 case Expr::ArraySubscriptExprClass: { 1892 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1893 return FindExpressionBaseAddress(ASE->getBase()); 1894 } 1895 case Expr::UnaryOperatorClass: { 1896 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1897 1898 if (Exp->getOpcode() == UnaryOperator::Deref) 1899 return FindExpressionBaseAddress(Exp->getSubExpr()); 1900 1901 return E; 1902 } 1903 } 1904} 1905 1906static const Expr* FindExpressionBaseAddress(const Expr* E) { 1907 switch (E->getStmtClass()) { 1908 default: 1909 return E; 1910 case Expr::ParenExprClass: { 1911 const ParenExpr* PE = cast<ParenExpr>(E); 1912 return FindExpressionBaseAddress(PE->getSubExpr()); 1913 } 1914 case Expr::UnaryOperatorClass: { 1915 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1916 1917 // C99 6.6p9 1918 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1919 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1920 1921 if (Exp->getOpcode() == UnaryOperator::Extension) 1922 return FindExpressionBaseAddress(Exp->getSubExpr()); 1923 1924 return E; 1925 } 1926 case Expr::BinaryOperatorClass: { 1927 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1928 1929 Expr *PExp = Exp->getLHS(); 1930 Expr *IExp = Exp->getRHS(); 1931 if (IExp->getType()->isPointerType()) 1932 std::swap(PExp, IExp); 1933 1934 return FindExpressionBaseAddress(PExp); 1935 } 1936 case Expr::ImplicitCastExprClass: { 1937 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1938 1939 // Check for implicit promotion 1940 if (SubExpr->getType()->isFunctionType() || 1941 SubExpr->getType()->isArrayType()) 1942 return FindExpressionBaseAddressLValue(SubExpr); 1943 1944 // Check for pointer->pointer cast 1945 if (SubExpr->getType()->isPointerType()) 1946 return FindExpressionBaseAddress(SubExpr); 1947 1948 // We assume that we have an arithmetic expression here; 1949 // if we don't, we'll figure it out later 1950 return 0; 1951 } 1952 case Expr::CStyleCastExprClass: { 1953 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1954 1955 // Check for pointer->pointer cast 1956 if (SubExpr->getType()->isPointerType()) 1957 return FindExpressionBaseAddress(SubExpr); 1958 1959 // We assume that we have an arithmetic expression here; 1960 // if we don't, we'll figure it out later 1961 return 0; 1962 } 1963 } 1964} 1965 1966bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1967 switch (Init->getStmtClass()) { 1968 default: 1969 InitializerElementNotConstant(Init); 1970 return true; 1971 case Expr::ParenExprClass: { 1972 const ParenExpr* PE = cast<ParenExpr>(Init); 1973 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1974 } 1975 case Expr::FloatingLiteralClass: 1976 case Expr::IntegerLiteralClass: 1977 case Expr::CharacterLiteralClass: 1978 case Expr::ImaginaryLiteralClass: 1979 case Expr::TypesCompatibleExprClass: 1980 case Expr::CXXBoolLiteralExprClass: 1981 return false; 1982 case Expr::CallExprClass: 1983 case Expr::CXXOperatorCallExprClass: { 1984 const CallExpr *CE = cast<CallExpr>(Init); 1985 1986 // Allow any constant foldable calls to builtins. 1987 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1988 return false; 1989 1990 InitializerElementNotConstant(Init); 1991 return true; 1992 } 1993 case Expr::DeclRefExprClass: 1994 case Expr::QualifiedDeclRefExprClass: { 1995 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1996 if (isa<EnumConstantDecl>(D)) 1997 return false; 1998 InitializerElementNotConstant(Init); 1999 return true; 2000 } 2001 case Expr::CompoundLiteralExprClass: 2002 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2003 // but vectors are allowed to be magic. 2004 if (Init->getType()->isVectorType()) 2005 return false; 2006 InitializerElementNotConstant(Init); 2007 return true; 2008 case Expr::UnaryOperatorClass: { 2009 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2010 2011 switch (Exp->getOpcode()) { 2012 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2013 // See C99 6.6p3. 2014 default: 2015 InitializerElementNotConstant(Init); 2016 return true; 2017 case UnaryOperator::OffsetOf: 2018 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2019 return false; 2020 InitializerElementNotConstant(Init); 2021 return true; 2022 case UnaryOperator::Extension: 2023 case UnaryOperator::LNot: 2024 case UnaryOperator::Plus: 2025 case UnaryOperator::Minus: 2026 case UnaryOperator::Not: 2027 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2028 } 2029 } 2030 case Expr::SizeOfAlignOfExprClass: { 2031 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2032 // Special check for void types, which are allowed as an extension 2033 if (Exp->getTypeOfArgument()->isVoidType()) 2034 return false; 2035 // alignof always evaluates to a constant. 2036 // FIXME: is sizeof(int[3.0]) a constant expression? 2037 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2038 InitializerElementNotConstant(Init); 2039 return true; 2040 } 2041 return false; 2042 } 2043 case Expr::BinaryOperatorClass: { 2044 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2045 2046 if (Exp->getLHS()->getType()->isArithmeticType() && 2047 Exp->getRHS()->getType()->isArithmeticType()) { 2048 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2049 CheckArithmeticConstantExpression(Exp->getRHS()); 2050 } 2051 2052 if (Exp->getLHS()->getType()->isPointerType() && 2053 Exp->getRHS()->getType()->isPointerType()) { 2054 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2055 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2056 2057 // Only allow a null (constant integer) base; we could 2058 // allow some additional cases if necessary, but this 2059 // is sufficient to cover offsetof-like constructs. 2060 if (!LHSBase && !RHSBase) { 2061 return CheckAddressConstantExpression(Exp->getLHS()) || 2062 CheckAddressConstantExpression(Exp->getRHS()); 2063 } 2064 } 2065 2066 InitializerElementNotConstant(Init); 2067 return true; 2068 } 2069 case Expr::ImplicitCastExprClass: 2070 case Expr::CStyleCastExprClass: { 2071 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2072 if (SubExpr->getType()->isArithmeticType()) 2073 return CheckArithmeticConstantExpression(SubExpr); 2074 2075 if (SubExpr->getType()->isPointerType()) { 2076 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2077 // If the pointer has a null base, this is an offsetof-like construct 2078 if (!Base) 2079 return CheckAddressConstantExpression(SubExpr); 2080 } 2081 2082 InitializerElementNotConstant(Init); 2083 return true; 2084 } 2085 case Expr::ConditionalOperatorClass: { 2086 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2087 2088 // If GNU extensions are disabled, we require all operands to be arithmetic 2089 // constant expressions. 2090 if (getLangOptions().NoExtensions) { 2091 return CheckArithmeticConstantExpression(Exp->getCond()) || 2092 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2093 CheckArithmeticConstantExpression(Exp->getRHS()); 2094 } 2095 2096 // Otherwise, we have to emulate some of the behavior of fold here. 2097 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2098 // because it can constant fold things away. To retain compatibility with 2099 // GCC code, we see if we can fold the condition to a constant (which we 2100 // should always be able to do in theory). If so, we only require the 2101 // specified arm of the conditional to be a constant. This is a horrible 2102 // hack, but is require by real world code that uses __builtin_constant_p. 2103 Expr::EvalResult EvalResult; 2104 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2105 EvalResult.HasSideEffects) { 2106 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2107 // won't be able to either. Use it to emit the diagnostic though. 2108 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2109 assert(Res && "Evaluate couldn't evaluate this constant?"); 2110 return Res; 2111 } 2112 2113 // Verify that the side following the condition is also a constant. 2114 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2115 if (EvalResult.Val.getInt() == 0) 2116 std::swap(TrueSide, FalseSide); 2117 2118 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2119 return true; 2120 2121 // Okay, the evaluated side evaluates to a constant, so we accept this. 2122 // Check to see if the other side is obviously not a constant. If so, 2123 // emit a warning that this is a GNU extension. 2124 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2125 Diag(Init->getExprLoc(), 2126 diag::ext_typecheck_expression_not_constant_but_accepted) 2127 << FalseSide->getSourceRange(); 2128 return false; 2129 } 2130 } 2131} 2132 2133bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2134 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2135 Init = DIE->getInit(); 2136 2137 Init = Init->IgnoreParens(); 2138 2139 if (Init->isEvaluatable(Context)) 2140 return false; 2141 2142 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2143 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2144 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2145 2146 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2147 return CheckForConstantInitializer(e->getInitializer(), DclT); 2148 2149 if (isa<ImplicitValueInitExpr>(Init)) { 2150 // FIXME: In C++, check for non-POD types. 2151 return false; 2152 } 2153 2154 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2155 unsigned numInits = Exp->getNumInits(); 2156 for (unsigned i = 0; i < numInits; i++) { 2157 // FIXME: Need to get the type of the declaration for C++, 2158 // because it could be a reference? 2159 2160 if (CheckForConstantInitializer(Exp->getInit(i), 2161 Exp->getInit(i)->getType())) 2162 return true; 2163 } 2164 return false; 2165 } 2166 2167 // FIXME: We can probably remove some of this code below, now that 2168 // Expr::Evaluate is doing the heavy lifting for scalars. 2169 2170 if (Init->isNullPointerConstant(Context)) 2171 return false; 2172 if (Init->getType()->isArithmeticType()) { 2173 QualType InitTy = Context.getCanonicalType(Init->getType()) 2174 .getUnqualifiedType(); 2175 if (InitTy == Context.BoolTy) { 2176 // Special handling for pointers implicitly cast to bool; 2177 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2178 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2179 Expr* SubE = ICE->getSubExpr(); 2180 if (SubE->getType()->isPointerType() || 2181 SubE->getType()->isArrayType() || 2182 SubE->getType()->isFunctionType()) { 2183 return CheckAddressConstantExpression(Init); 2184 } 2185 } 2186 } else if (InitTy->isIntegralType()) { 2187 Expr* SubE = 0; 2188 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2189 SubE = CE->getSubExpr(); 2190 // Special check for pointer cast to int; we allow as an extension 2191 // an address constant cast to an integer if the integer 2192 // is of an appropriate width (this sort of code is apparently used 2193 // in some places). 2194 // FIXME: Add pedwarn? 2195 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2196 if (SubE && (SubE->getType()->isPointerType() || 2197 SubE->getType()->isArrayType() || 2198 SubE->getType()->isFunctionType())) { 2199 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2200 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2201 if (IntWidth >= PointerWidth) 2202 return CheckAddressConstantExpression(Init); 2203 } 2204 } 2205 2206 return CheckArithmeticConstantExpression(Init); 2207 } 2208 2209 if (Init->getType()->isPointerType()) 2210 return CheckAddressConstantExpression(Init); 2211 2212 // An array type at the top level that isn't an init-list must 2213 // be a string literal 2214 if (Init->getType()->isArrayType()) 2215 return false; 2216 2217 if (Init->getType()->isFunctionType()) 2218 return false; 2219 2220 // Allow block exprs at top level. 2221 if (Init->getType()->isBlockPointerType()) 2222 return false; 2223 2224 // GCC cast to union extension 2225 // note: the validity of the cast expr is checked by CheckCastTypes() 2226 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2227 QualType T = C->getType(); 2228 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2229 } 2230 2231 InitializerElementNotConstant(Init); 2232 return true; 2233} 2234 2235void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2236 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2237} 2238 2239/// AddInitializerToDecl - Adds the initializer Init to the 2240/// declaration dcl. If DirectInit is true, this is C++ direct 2241/// initialization rather than copy initialization. 2242void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2243 Decl *RealDecl = static_cast<Decl *>(dcl); 2244 Expr *Init = static_cast<Expr *>(init.release()); 2245 assert(Init && "missing initializer"); 2246 2247 // If there is no declaration, there was an error parsing it. Just ignore 2248 // the initializer. 2249 if (RealDecl == 0) { 2250 delete Init; 2251 return; 2252 } 2253 2254 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2255 if (!VDecl) { 2256 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2257 RealDecl->setInvalidDecl(); 2258 return; 2259 } 2260 // Get the decls type and save a reference for later, since 2261 // CheckInitializerTypes may change it. 2262 QualType DclT = VDecl->getType(), SavT = DclT; 2263 if (VDecl->isBlockVarDecl()) { 2264 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2265 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2266 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2267 VDecl->setInvalidDecl(); 2268 } else if (!VDecl->isInvalidDecl()) { 2269 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2270 VDecl->getDeclName(), DirectInit)) 2271 VDecl->setInvalidDecl(); 2272 2273 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2274 if (!getLangOptions().CPlusPlus) { 2275 if (SC == VarDecl::Static) // C99 6.7.8p4. 2276 CheckForConstantInitializer(Init, DclT); 2277 } 2278 } 2279 } else if (VDecl->isFileVarDecl()) { 2280 if (VDecl->getStorageClass() == VarDecl::Extern) 2281 Diag(VDecl->getLocation(), diag::warn_extern_init); 2282 if (!VDecl->isInvalidDecl()) 2283 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2284 VDecl->getDeclName(), DirectInit)) 2285 VDecl->setInvalidDecl(); 2286 2287 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2288 if (!getLangOptions().CPlusPlus) { 2289 // C99 6.7.8p4. All file scoped initializers need to be constant. 2290 CheckForConstantInitializer(Init, DclT); 2291 } 2292 } 2293 // If the type changed, it means we had an incomplete type that was 2294 // completed by the initializer. For example: 2295 // int ary[] = { 1, 3, 5 }; 2296 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2297 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2298 VDecl->setType(DclT); 2299 Init->setType(DclT); 2300 } 2301 2302 // Attach the initializer to the decl. 2303 VDecl->setInit(Init); 2304 return; 2305} 2306 2307void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2308 Decl *RealDecl = static_cast<Decl *>(dcl); 2309 2310 // If there is no declaration, there was an error parsing it. Just ignore it. 2311 if (RealDecl == 0) 2312 return; 2313 2314 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2315 QualType Type = Var->getType(); 2316 // C++ [dcl.init.ref]p3: 2317 // The initializer can be omitted for a reference only in a 2318 // parameter declaration (8.3.5), in the declaration of a 2319 // function return type, in the declaration of a class member 2320 // within its class declaration (9.2), and where the extern 2321 // specifier is explicitly used. 2322 if (Type->isReferenceType() && 2323 Var->getStorageClass() != VarDecl::Extern && 2324 Var->getStorageClass() != VarDecl::PrivateExtern) { 2325 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2326 << Var->getDeclName() 2327 << SourceRange(Var->getLocation(), Var->getLocation()); 2328 Var->setInvalidDecl(); 2329 return; 2330 } 2331 2332 // C++ [dcl.init]p9: 2333 // 2334 // If no initializer is specified for an object, and the object 2335 // is of (possibly cv-qualified) non-POD class type (or array 2336 // thereof), the object shall be default-initialized; if the 2337 // object is of const-qualified type, the underlying class type 2338 // shall have a user-declared default constructor. 2339 if (getLangOptions().CPlusPlus) { 2340 QualType InitType = Type; 2341 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2342 InitType = Array->getElementType(); 2343 if (Var->getStorageClass() != VarDecl::Extern && 2344 Var->getStorageClass() != VarDecl::PrivateExtern && 2345 InitType->isRecordType()) { 2346 const CXXConstructorDecl *Constructor 2347 = PerformInitializationByConstructor(InitType, 0, 0, 2348 Var->getLocation(), 2349 SourceRange(Var->getLocation(), 2350 Var->getLocation()), 2351 Var->getDeclName(), 2352 IK_Default); 2353 if (!Constructor) 2354 Var->setInvalidDecl(); 2355 } 2356 } 2357 2358#if 0 2359 // FIXME: Temporarily disabled because we are not properly parsing 2360 // linkage specifications on declarations, e.g., 2361 // 2362 // extern "C" const CGPoint CGPointerZero; 2363 // 2364 // C++ [dcl.init]p9: 2365 // 2366 // If no initializer is specified for an object, and the 2367 // object is of (possibly cv-qualified) non-POD class type (or 2368 // array thereof), the object shall be default-initialized; if 2369 // the object is of const-qualified type, the underlying class 2370 // type shall have a user-declared default 2371 // constructor. Otherwise, if no initializer is specified for 2372 // an object, the object and its subobjects, if any, have an 2373 // indeterminate initial value; if the object or any of its 2374 // subobjects are of const-qualified type, the program is 2375 // ill-formed. 2376 // 2377 // This isn't technically an error in C, so we don't diagnose it. 2378 // 2379 // FIXME: Actually perform the POD/user-defined default 2380 // constructor check. 2381 if (getLangOptions().CPlusPlus && 2382 Context.getCanonicalType(Type).isConstQualified() && 2383 Var->getStorageClass() != VarDecl::Extern) 2384 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2385 << Var->getName() 2386 << SourceRange(Var->getLocation(), Var->getLocation()); 2387#endif 2388 } 2389} 2390 2391/// The declarators are chained together backwards, reverse the list. 2392Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2393 // Often we have single declarators, handle them quickly. 2394 Decl *GroupDecl = static_cast<Decl*>(group); 2395 if (GroupDecl == 0) 2396 return 0; 2397 2398 Decl *Group = dyn_cast<Decl>(GroupDecl); 2399 Decl *NewGroup = 0; 2400 if (Group->getNextDeclarator() == 0) 2401 NewGroup = Group; 2402 else { // reverse the list. 2403 while (Group) { 2404 Decl *Next = Group->getNextDeclarator(); 2405 Group->setNextDeclarator(NewGroup); 2406 NewGroup = Group; 2407 Group = Next; 2408 } 2409 } 2410 // Perform semantic analysis that depends on having fully processed both 2411 // the declarator and initializer. 2412 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2413 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2414 if (!IDecl) 2415 continue; 2416 QualType T = IDecl->getType(); 2417 2418 if (T->isVariableArrayType()) { 2419 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2420 2421 // FIXME: This won't give the correct result for 2422 // int a[10][n]; 2423 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2424 if (IDecl->isFileVarDecl()) { 2425 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2426 SizeRange; 2427 2428 IDecl->setInvalidDecl(); 2429 } else { 2430 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2431 // static storage duration, it shall not have a variable length array. 2432 if (IDecl->getStorageClass() == VarDecl::Static) { 2433 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2434 << SizeRange; 2435 IDecl->setInvalidDecl(); 2436 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2437 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2438 << SizeRange; 2439 IDecl->setInvalidDecl(); 2440 } 2441 } 2442 } else if (T->isVariablyModifiedType()) { 2443 if (IDecl->isFileVarDecl()) { 2444 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2445 IDecl->setInvalidDecl(); 2446 } else { 2447 if (IDecl->getStorageClass() == VarDecl::Extern) { 2448 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2449 IDecl->setInvalidDecl(); 2450 } 2451 } 2452 } 2453 2454 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2455 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2456 if (IDecl->isBlockVarDecl() && 2457 IDecl->getStorageClass() != VarDecl::Extern) { 2458 if (!IDecl->isInvalidDecl() && 2459 DiagnoseIncompleteType(IDecl->getLocation(), T, 2460 diag::err_typecheck_decl_incomplete_type)) 2461 IDecl->setInvalidDecl(); 2462 } 2463 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2464 // object that has file scope without an initializer, and without a 2465 // storage-class specifier or with the storage-class specifier "static", 2466 // constitutes a tentative definition. Note: A tentative definition with 2467 // external linkage is valid (C99 6.2.2p5). 2468 if (isTentativeDefinition(IDecl)) { 2469 if (T->isIncompleteArrayType()) { 2470 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2471 // array to be completed. Don't issue a diagnostic. 2472 } else if (!IDecl->isInvalidDecl() && 2473 DiagnoseIncompleteType(IDecl->getLocation(), T, 2474 diag::err_typecheck_decl_incomplete_type)) 2475 // C99 6.9.2p3: If the declaration of an identifier for an object is 2476 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2477 // declared type shall not be an incomplete type. 2478 IDecl->setInvalidDecl(); 2479 } 2480 if (IDecl->isFileVarDecl()) 2481 CheckForFileScopedRedefinitions(S, IDecl); 2482 } 2483 return NewGroup; 2484} 2485 2486/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2487/// to introduce parameters into function prototype scope. 2488Sema::DeclTy * 2489Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2490 const DeclSpec &DS = D.getDeclSpec(); 2491 2492 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2493 VarDecl::StorageClass StorageClass = VarDecl::None; 2494 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2495 StorageClass = VarDecl::Register; 2496 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2497 Diag(DS.getStorageClassSpecLoc(), 2498 diag::err_invalid_storage_class_in_func_decl); 2499 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2500 } 2501 if (DS.isThreadSpecified()) { 2502 Diag(DS.getThreadSpecLoc(), 2503 diag::err_invalid_storage_class_in_func_decl); 2504 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2505 } 2506 2507 // Check that there are no default arguments inside the type of this 2508 // parameter (C++ only). 2509 if (getLangOptions().CPlusPlus) 2510 CheckExtraCXXDefaultArguments(D); 2511 2512 // In this context, we *do not* check D.getInvalidType(). If the declarator 2513 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2514 // though it will not reflect the user specified type. 2515 QualType parmDeclType = GetTypeForDeclarator(D, S); 2516 2517 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2518 2519 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2520 // Can this happen for params? We already checked that they don't conflict 2521 // among each other. Here they can only shadow globals, which is ok. 2522 IdentifierInfo *II = D.getIdentifier(); 2523 if (II) { 2524 if (Decl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2525 if (PrevDecl->isTemplateParameter()) { 2526 // Maybe we will complain about the shadowed template parameter. 2527 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2528 // Just pretend that we didn't see the previous declaration. 2529 PrevDecl = 0; 2530 } else if (S->isDeclScope(PrevDecl)) { 2531 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2532 2533 // Recover by removing the name 2534 II = 0; 2535 D.SetIdentifier(0, D.getIdentifierLoc()); 2536 } 2537 } 2538 } 2539 2540 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2541 // Doing the promotion here has a win and a loss. The win is the type for 2542 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2543 // code generator). The loss is the orginal type isn't preserved. For example: 2544 // 2545 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2546 // int blockvardecl[5]; 2547 // sizeof(parmvardecl); // size == 4 2548 // sizeof(blockvardecl); // size == 20 2549 // } 2550 // 2551 // For expressions, all implicit conversions are captured using the 2552 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2553 // 2554 // FIXME: If a source translation tool needs to see the original type, then 2555 // we need to consider storing both types (in ParmVarDecl)... 2556 // 2557 if (parmDeclType->isArrayType()) { 2558 // int x[restrict 4] -> int *restrict 2559 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2560 } else if (parmDeclType->isFunctionType()) 2561 parmDeclType = Context.getPointerType(parmDeclType); 2562 2563 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2564 D.getIdentifierLoc(), II, 2565 parmDeclType, StorageClass, 2566 0); 2567 2568 if (D.getInvalidType()) 2569 New->setInvalidDecl(); 2570 2571 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2572 if (D.getCXXScopeSpec().isSet()) { 2573 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2574 << D.getCXXScopeSpec().getRange(); 2575 New->setInvalidDecl(); 2576 } 2577 2578 // Add the parameter declaration into this scope. 2579 S->AddDecl(New); 2580 if (II) 2581 IdResolver.AddDecl(New); 2582 2583 ProcessDeclAttributes(New, D); 2584 return New; 2585 2586} 2587 2588void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2589 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2590 "Not a function declarator!"); 2591 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2592 2593 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2594 // for a K&R function. 2595 if (!FTI.hasPrototype) { 2596 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2597 if (FTI.ArgInfo[i].Param == 0) { 2598 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2599 << FTI.ArgInfo[i].Ident; 2600 // Implicitly declare the argument as type 'int' for lack of a better 2601 // type. 2602 DeclSpec DS; 2603 const char* PrevSpec; // unused 2604 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2605 PrevSpec); 2606 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2607 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2608 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2609 } 2610 } 2611 } 2612} 2613 2614Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2615 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2616 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2617 "Not a function declarator!"); 2618 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2619 2620 if (FTI.hasPrototype) { 2621 // FIXME: Diagnose arguments without names in C. 2622 } 2623 2624 Scope *ParentScope = FnBodyScope->getParent(); 2625 2626 return ActOnStartOfFunctionDef(FnBodyScope, 2627 ActOnDeclarator(ParentScope, D, 0, 2628 /*IsFunctionDefinition=*/true)); 2629} 2630 2631Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2632 Decl *decl = static_cast<Decl*>(D); 2633 FunctionDecl *FD = cast<FunctionDecl>(decl); 2634 2635 // See if this is a redefinition. 2636 const FunctionDecl *Definition; 2637 if (FD->getBody(Definition)) { 2638 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2639 Diag(Definition->getLocation(), diag::note_previous_definition); 2640 } 2641 2642 PushDeclContext(FnBodyScope, FD); 2643 2644 // Check the validity of our function parameters 2645 CheckParmsForFunctionDef(FD); 2646 2647 // Introduce our parameters into the function scope 2648 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2649 ParmVarDecl *Param = FD->getParamDecl(p); 2650 Param->setOwningFunction(FD); 2651 2652 // If this has an identifier, add it to the scope stack. 2653 if (Param->getIdentifier()) 2654 PushOnScopeChains(Param, FnBodyScope); 2655 } 2656 2657 // Checking attributes of current function definition 2658 // dllimport attribute. 2659 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2660 // dllimport attribute cannot be applied to definition. 2661 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2662 Diag(FD->getLocation(), 2663 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2664 << "dllimport"; 2665 FD->setInvalidDecl(); 2666 return FD; 2667 } else { 2668 // If a symbol previously declared dllimport is later defined, the 2669 // attribute is ignored in subsequent references, and a warning is 2670 // emitted. 2671 Diag(FD->getLocation(), 2672 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2673 << FD->getNameAsCString() << "dllimport"; 2674 } 2675 } 2676 return FD; 2677} 2678 2679Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2680 Decl *dcl = static_cast<Decl *>(D); 2681 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2682 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2683 FD->setBody(Body); 2684 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2685 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2686 MD->setBody((Stmt*)Body); 2687 } else 2688 return 0; 2689 PopDeclContext(); 2690 // Verify and clean out per-function state. 2691 2692 // Check goto/label use. 2693 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2694 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2695 // Verify that we have no forward references left. If so, there was a goto 2696 // or address of a label taken, but no definition of it. Label fwd 2697 // definitions are indicated with a null substmt. 2698 if (I->second->getSubStmt() == 0) { 2699 LabelStmt *L = I->second; 2700 // Emit error. 2701 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2702 2703 // At this point, we have gotos that use the bogus label. Stitch it into 2704 // the function body so that they aren't leaked and that the AST is well 2705 // formed. 2706 if (Body) { 2707 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2708 cast<CompoundStmt>(Body)->push_back(L); 2709 } else { 2710 // The whole function wasn't parsed correctly, just delete this. 2711 delete L; 2712 } 2713 } 2714 } 2715 LabelMap.clear(); 2716 2717 return D; 2718} 2719 2720/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2721/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2722NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2723 IdentifierInfo &II, Scope *S) { 2724 // Extension in C99. Legal in C90, but warn about it. 2725 if (getLangOptions().C99) 2726 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2727 else 2728 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2729 2730 // FIXME: handle stuff like: 2731 // void foo() { extern float X(); } 2732 // void bar() { X(); } <-- implicit decl for X in another scope. 2733 2734 // Set a Declarator for the implicit definition: int foo(); 2735 const char *Dummy; 2736 DeclSpec DS; 2737 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2738 Error = Error; // Silence warning. 2739 assert(!Error && "Error setting up implicit decl!"); 2740 Declarator D(DS, Declarator::BlockContext); 2741 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D)); 2742 D.SetIdentifier(&II, Loc); 2743 2744 // Insert this function into translation-unit scope. 2745 2746 DeclContext *PrevDC = CurContext; 2747 CurContext = Context.getTranslationUnitDecl(); 2748 2749 FunctionDecl *FD = 2750 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2751 FD->setImplicit(); 2752 2753 CurContext = PrevDC; 2754 2755 return FD; 2756} 2757 2758 2759TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2760 Decl *LastDeclarator) { 2761 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2762 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2763 2764 // Scope manipulation handled by caller. 2765 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2766 D.getIdentifierLoc(), 2767 D.getIdentifier(), 2768 T); 2769 NewTD->setNextDeclarator(LastDeclarator); 2770 if (D.getInvalidType()) 2771 NewTD->setInvalidDecl(); 2772 return NewTD; 2773} 2774 2775/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2776/// former case, Name will be non-null. In the later case, Name will be null. 2777/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2778/// reference/declaration/definition of a tag. 2779Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2780 SourceLocation KWLoc, const CXXScopeSpec &SS, 2781 IdentifierInfo *Name, SourceLocation NameLoc, 2782 AttributeList *Attr, 2783 MultiTemplateParamsArg TemplateParameterLists) { 2784 // If this is not a definition, it must have a name. 2785 assert((Name != 0 || TK == TK_Definition) && 2786 "Nameless record must be a definition!"); 2787 2788 TagDecl::TagKind Kind; 2789 switch (TagSpec) { 2790 default: assert(0 && "Unknown tag type!"); 2791 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2792 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2793 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2794 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2795 } 2796 2797 DeclContext *SearchDC = CurContext; 2798 DeclContext *DC = CurContext; 2799 DeclContext *LexicalContext = CurContext; 2800 Decl *PrevDecl = 0; 2801 2802 bool Invalid = false; 2803 2804 if (Name && SS.isNotEmpty()) { 2805 // We have a nested-name tag ('struct foo::bar'). 2806 2807 // Check for invalid 'foo::'. 2808 if (SS.isInvalid()) { 2809 Name = 0; 2810 goto CreateNewDecl; 2811 } 2812 2813 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2814 // Look-up name inside 'foo::'. 2815 PrevDecl = dyn_cast_or_null<TagDecl>( 2816 LookupQualifiedName(DC, Name, LookupTagName).getAsDecl()); 2817 2818 // A tag 'foo::bar' must already exist. 2819 if (PrevDecl == 0) { 2820 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2821 Name = 0; 2822 goto CreateNewDecl; 2823 } 2824 } else if (Name) { 2825 // If this is a named struct, check to see if there was a previous forward 2826 // declaration or definition. 2827 Decl *D = LookupName(S, Name, LookupTagName); 2828 PrevDecl = dyn_cast_or_null<NamedDecl>(D); 2829 2830 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2831 // FIXME: This makes sure that we ignore the contexts associated 2832 // with C structs, unions, and enums when looking for a matching 2833 // tag declaration or definition. See the similar lookup tweak 2834 // in Sema::LookupName; is there a better way to deal with this? 2835 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2836 SearchDC = SearchDC->getParent(); 2837 } 2838 } 2839 2840 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2841 // Maybe we will complain about the shadowed template parameter. 2842 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2843 // Just pretend that we didn't see the previous declaration. 2844 PrevDecl = 0; 2845 } 2846 2847 if (PrevDecl) { 2848 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2849 // If this is a use of a previous tag, or if the tag is already declared 2850 // in the same scope (so that the definition/declaration completes or 2851 // rementions the tag), reuse the decl. 2852 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2853 // Make sure that this wasn't declared as an enum and now used as a 2854 // struct or something similar. 2855 if (PrevTagDecl->getTagKind() != Kind) { 2856 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2857 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2858 // Recover by making this an anonymous redefinition. 2859 Name = 0; 2860 PrevDecl = 0; 2861 Invalid = true; 2862 } else { 2863 // If this is a use, just return the declaration we found. 2864 2865 // FIXME: In the future, return a variant or some other clue 2866 // for the consumer of this Decl to know it doesn't own it. 2867 // For our current ASTs this shouldn't be a problem, but will 2868 // need to be changed with DeclGroups. 2869 if (TK == TK_Reference) 2870 return PrevDecl; 2871 2872 // Diagnose attempts to redefine a tag. 2873 if (TK == TK_Definition) { 2874 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2875 Diag(NameLoc, diag::err_redefinition) << Name; 2876 Diag(Def->getLocation(), diag::note_previous_definition); 2877 // If this is a redefinition, recover by making this 2878 // struct be anonymous, which will make any later 2879 // references get the previous definition. 2880 Name = 0; 2881 PrevDecl = 0; 2882 Invalid = true; 2883 } else { 2884 // If the type is currently being defined, complain 2885 // about a nested redefinition. 2886 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2887 if (Tag->isBeingDefined()) { 2888 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2889 Diag(PrevTagDecl->getLocation(), 2890 diag::note_previous_definition); 2891 Name = 0; 2892 PrevDecl = 0; 2893 Invalid = true; 2894 } 2895 } 2896 2897 // Okay, this is definition of a previously declared or referenced 2898 // tag PrevDecl. We're going to create a new Decl for it. 2899 } 2900 } 2901 // If we get here we have (another) forward declaration or we 2902 // have a definition. Just create a new decl. 2903 } else { 2904 // If we get here, this is a definition of a new tag type in a nested 2905 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2906 // new decl/type. We set PrevDecl to NULL so that the entities 2907 // have distinct types. 2908 PrevDecl = 0; 2909 } 2910 // If we get here, we're going to create a new Decl. If PrevDecl 2911 // is non-NULL, it's a definition of the tag declared by 2912 // PrevDecl. If it's NULL, we have a new definition. 2913 } else { 2914 // PrevDecl is a namespace, template, or anything else 2915 // that lives in the IDNS_Tag identifier namespace. 2916 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2917 // The tag name clashes with a namespace name, issue an error and 2918 // recover by making this tag be anonymous. 2919 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2920 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2921 Name = 0; 2922 PrevDecl = 0; 2923 Invalid = true; 2924 } else { 2925 // The existing declaration isn't relevant to us; we're in a 2926 // new scope, so clear out the previous declaration. 2927 PrevDecl = 0; 2928 } 2929 } 2930 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2931 (Kind != TagDecl::TK_enum)) { 2932 // C++ [basic.scope.pdecl]p5: 2933 // -- for an elaborated-type-specifier of the form 2934 // 2935 // class-key identifier 2936 // 2937 // if the elaborated-type-specifier is used in the 2938 // decl-specifier-seq or parameter-declaration-clause of a 2939 // function defined in namespace scope, the identifier is 2940 // declared as a class-name in the namespace that contains 2941 // the declaration; otherwise, except as a friend 2942 // declaration, the identifier is declared in the smallest 2943 // non-class, non-function-prototype scope that contains the 2944 // declaration. 2945 // 2946 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2947 // C structs and unions. 2948 2949 // Find the context where we'll be declaring the tag. 2950 // FIXME: We would like to maintain the current DeclContext as the 2951 // lexical context, 2952 while (DC->isRecord()) 2953 DC = DC->getParent(); 2954 LexicalContext = DC; 2955 2956 // Find the scope where we'll be declaring the tag. 2957 while (S->isClassScope() || 2958 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 2959 ((S->getFlags() & Scope::DeclScope) == 0) || 2960 (S->getEntity() && 2961 ((DeclContext *)S->getEntity())->isTransparentContext())) 2962 S = S->getParent(); 2963 } 2964 2965CreateNewDecl: 2966 2967 // If there is an identifier, use the location of the identifier as the 2968 // location of the decl, otherwise use the location of the struct/union 2969 // keyword. 2970 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2971 2972 // Otherwise, create a new declaration. If there is a previous 2973 // declaration of the same entity, the two will be linked via 2974 // PrevDecl. 2975 TagDecl *New; 2976 2977 if (Kind == TagDecl::TK_enum) { 2978 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2979 // enum X { A, B, C } D; D should chain to X. 2980 New = EnumDecl::Create(Context, DC, Loc, Name, 2981 cast_or_null<EnumDecl>(PrevDecl)); 2982 // If this is an undefined enum, warn. 2983 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2984 } else { 2985 // struct/union/class 2986 2987 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2988 // struct X { int A; } D; D should chain to X. 2989 if (getLangOptions().CPlusPlus) 2990 // FIXME: Look for a way to use RecordDecl for simple structs. 2991 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2992 cast_or_null<CXXRecordDecl>(PrevDecl)); 2993 else 2994 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2995 cast_or_null<RecordDecl>(PrevDecl)); 2996 } 2997 2998 if (Kind != TagDecl::TK_enum) { 2999 // Handle #pragma pack: if the #pragma pack stack has non-default 3000 // alignment, make up a packed attribute for this decl. These 3001 // attributes are checked when the ASTContext lays out the 3002 // structure. 3003 // 3004 // It is important for implementing the correct semantics that this 3005 // happen here (in act on tag decl). The #pragma pack stack is 3006 // maintained as a result of parser callbacks which can occur at 3007 // many points during the parsing of a struct declaration (because 3008 // the #pragma tokens are effectively skipped over during the 3009 // parsing of the struct). 3010 if (unsigned Alignment = PackContext.getAlignment()) 3011 New->addAttr(new PackedAttr(Alignment * 8)); 3012 } 3013 3014 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3015 // C++ [dcl.typedef]p3: 3016 // [...] Similarly, in a given scope, a class or enumeration 3017 // shall not be declared with the same name as a typedef-name 3018 // that is declared in that scope and refers to a type other 3019 // than the class or enumeration itself. 3020 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3021 TypedefDecl *PrevTypedef = 0; 3022 if (Lookup.getKind() == LookupResult::Found) 3023 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3024 3025 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3026 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3027 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3028 Diag(Loc, diag::err_tag_definition_of_typedef) 3029 << Context.getTypeDeclType(New) 3030 << PrevTypedef->getUnderlyingType(); 3031 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3032 Invalid = true; 3033 } 3034 } 3035 3036 if (Invalid) 3037 New->setInvalidDecl(); 3038 3039 if (Attr) 3040 ProcessDeclAttributeList(New, Attr); 3041 3042 // If we're declaring or defining a tag in function prototype scope 3043 // in C, note that this type can only be used within the function. 3044 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3045 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3046 3047 // Set the lexical context. If the tag has a C++ scope specifier, the 3048 // lexical context will be different from the semantic context. 3049 New->setLexicalDeclContext(LexicalContext); 3050 3051 if (TK == TK_Definition) 3052 New->startDefinition(); 3053 3054 // If this has an identifier, add it to the scope stack. 3055 if (Name) { 3056 S = getNonFieldDeclScope(S); 3057 3058 // Add it to the decl chain. 3059 if (LexicalContext != CurContext) { 3060 // FIXME: PushOnScopeChains should not rely on CurContext! 3061 DeclContext *OldContext = CurContext; 3062 CurContext = LexicalContext; 3063 PushOnScopeChains(New, S); 3064 CurContext = OldContext; 3065 } else 3066 PushOnScopeChains(New, S); 3067 } else { 3068 LexicalContext->addDecl(New); 3069 } 3070 3071 return New; 3072} 3073 3074void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3075 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3076 3077 // Enter the tag context. 3078 PushDeclContext(S, Tag); 3079 3080 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3081 FieldCollector->StartClass(); 3082 3083 if (Record->getIdentifier()) { 3084 // C++ [class]p2: 3085 // [...] The class-name is also inserted into the scope of the 3086 // class itself; this is known as the injected-class-name. For 3087 // purposes of access checking, the injected-class-name is treated 3088 // as if it were a public member name. 3089 RecordDecl *InjectedClassName 3090 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3091 CurContext, Record->getLocation(), 3092 Record->getIdentifier(), Record); 3093 InjectedClassName->setImplicit(); 3094 PushOnScopeChains(InjectedClassName, S); 3095 } 3096 } 3097} 3098 3099void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3100 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3101 3102 if (isa<CXXRecordDecl>(Tag)) 3103 FieldCollector->FinishClass(); 3104 3105 // Exit this scope of this tag's definition. 3106 PopDeclContext(); 3107 3108 // Notify the consumer that we've defined a tag. 3109 Consumer.HandleTagDeclDefinition(Tag); 3110} 3111 3112/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3113/// types into constant array types in certain situations which would otherwise 3114/// be errors (for GCC compatibility). 3115static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3116 ASTContext &Context) { 3117 // This method tries to turn a variable array into a constant 3118 // array even when the size isn't an ICE. This is necessary 3119 // for compatibility with code that depends on gcc's buggy 3120 // constant expression folding, like struct {char x[(int)(char*)2];} 3121 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3122 if (!VLATy) return QualType(); 3123 3124 Expr::EvalResult EvalResult; 3125 if (!VLATy->getSizeExpr() || 3126 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3127 return QualType(); 3128 3129 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3130 llvm::APSInt &Res = EvalResult.Val.getInt(); 3131 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3132 return Context.getConstantArrayType(VLATy->getElementType(), 3133 Res, ArrayType::Normal, 0); 3134 return QualType(); 3135} 3136 3137bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3138 QualType FieldTy, const Expr *BitWidth) { 3139 // FIXME: 6.7.2.1p4 - verify the field type. 3140 3141 llvm::APSInt Value; 3142 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3143 return true; 3144 3145 // Zero-width bitfield is ok for anonymous field. 3146 if (Value == 0 && FieldName) 3147 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3148 3149 if (Value.isNegative()) 3150 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3151 3152 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3153 // FIXME: We won't need the 0 size once we check that the field type is valid. 3154 if (TypeSize && Value.getZExtValue() > TypeSize) 3155 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3156 << FieldName << (unsigned)TypeSize; 3157 3158 return false; 3159} 3160 3161/// ActOnField - Each field of a struct/union/class is passed into this in order 3162/// to create a FieldDecl object for it. 3163Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3164 SourceLocation DeclStart, 3165 Declarator &D, ExprTy *BitfieldWidth) { 3166 IdentifierInfo *II = D.getIdentifier(); 3167 Expr *BitWidth = (Expr*)BitfieldWidth; 3168 SourceLocation Loc = DeclStart; 3169 RecordDecl *Record = (RecordDecl *)TagD; 3170 if (II) Loc = D.getIdentifierLoc(); 3171 3172 // FIXME: Unnamed fields can be handled in various different ways, for 3173 // example, unnamed unions inject all members into the struct namespace! 3174 3175 QualType T = GetTypeForDeclarator(D, S); 3176 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3177 bool InvalidDecl = false; 3178 3179 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3180 // than a variably modified type. 3181 if (T->isVariablyModifiedType()) { 3182 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3183 if (!FixedTy.isNull()) { 3184 Diag(Loc, diag::warn_illegal_constant_array_size); 3185 T = FixedTy; 3186 } else { 3187 Diag(Loc, diag::err_typecheck_field_variable_size); 3188 T = Context.IntTy; 3189 InvalidDecl = true; 3190 } 3191 } 3192 3193 if (BitWidth) { 3194 if (VerifyBitField(Loc, II, T, BitWidth)) 3195 InvalidDecl = true; 3196 } else { 3197 // Not a bitfield. 3198 3199 // validate II. 3200 3201 } 3202 3203 // FIXME: Chain fielddecls together. 3204 FieldDecl *NewFD; 3205 3206 NewFD = FieldDecl::Create(Context, Record, 3207 Loc, II, T, BitWidth, 3208 D.getDeclSpec().getStorageClassSpec() == 3209 DeclSpec::SCS_mutable); 3210 3211 if (II) { 3212 Decl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3213 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3214 && !isa<TagDecl>(PrevDecl)) { 3215 Diag(Loc, diag::err_duplicate_member) << II; 3216 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3217 NewFD->setInvalidDecl(); 3218 Record->setInvalidDecl(); 3219 } 3220 } 3221 3222 if (getLangOptions().CPlusPlus) { 3223 CheckExtraCXXDefaultArguments(D); 3224 if (!T->isPODType()) 3225 cast<CXXRecordDecl>(Record)->setPOD(false); 3226 } 3227 3228 ProcessDeclAttributes(NewFD, D); 3229 3230 if (D.getInvalidType() || InvalidDecl) 3231 NewFD->setInvalidDecl(); 3232 3233 if (II) { 3234 PushOnScopeChains(NewFD, S); 3235 } else 3236 Record->addDecl(NewFD); 3237 3238 return NewFD; 3239} 3240 3241/// TranslateIvarVisibility - Translate visibility from a token ID to an 3242/// AST enum value. 3243static ObjCIvarDecl::AccessControl 3244TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3245 switch (ivarVisibility) { 3246 default: assert(0 && "Unknown visitibility kind"); 3247 case tok::objc_private: return ObjCIvarDecl::Private; 3248 case tok::objc_public: return ObjCIvarDecl::Public; 3249 case tok::objc_protected: return ObjCIvarDecl::Protected; 3250 case tok::objc_package: return ObjCIvarDecl::Package; 3251 } 3252} 3253 3254/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3255/// in order to create an IvarDecl object for it. 3256Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3257 SourceLocation DeclStart, 3258 Declarator &D, ExprTy *BitfieldWidth, 3259 tok::ObjCKeywordKind Visibility) { 3260 3261 IdentifierInfo *II = D.getIdentifier(); 3262 Expr *BitWidth = (Expr*)BitfieldWidth; 3263 SourceLocation Loc = DeclStart; 3264 if (II) Loc = D.getIdentifierLoc(); 3265 3266 // FIXME: Unnamed fields can be handled in various different ways, for 3267 // example, unnamed unions inject all members into the struct namespace! 3268 3269 QualType T = GetTypeForDeclarator(D, S); 3270 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3271 bool InvalidDecl = false; 3272 3273 if (BitWidth) { 3274 // TODO: Validate. 3275 //printf("WARNING: BITFIELDS IGNORED!\n"); 3276 3277 // 6.7.2.1p3 3278 // 6.7.2.1p4 3279 3280 } else { 3281 // Not a bitfield. 3282 3283 // validate II. 3284 3285 } 3286 3287 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3288 // than a variably modified type. 3289 if (T->isVariablyModifiedType()) { 3290 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3291 InvalidDecl = true; 3292 } 3293 3294 // Get the visibility (access control) for this ivar. 3295 ObjCIvarDecl::AccessControl ac = 3296 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3297 : ObjCIvarDecl::None; 3298 3299 // Construct the decl. 3300 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3301 (Expr *)BitfieldWidth); 3302 3303 if (II) { 3304 Decl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3305 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3306 && !isa<TagDecl>(PrevDecl)) { 3307 Diag(Loc, diag::err_duplicate_member) << II; 3308 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3309 NewID->setInvalidDecl(); 3310 } 3311 } 3312 3313 // Process attributes attached to the ivar. 3314 ProcessDeclAttributes(NewID, D); 3315 3316 if (D.getInvalidType() || InvalidDecl) 3317 NewID->setInvalidDecl(); 3318 3319 if (II) { 3320 // FIXME: When interfaces are DeclContexts, we'll need to add 3321 // these to the interface. 3322 S->AddDecl(NewID); 3323 IdResolver.AddDecl(NewID); 3324 } 3325 3326 return NewID; 3327} 3328 3329void Sema::ActOnFields(Scope* S, 3330 SourceLocation RecLoc, DeclTy *RecDecl, 3331 DeclTy **Fields, unsigned NumFields, 3332 SourceLocation LBrac, SourceLocation RBrac, 3333 AttributeList *Attr) { 3334 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3335 assert(EnclosingDecl && "missing record or interface decl"); 3336 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3337 3338 // Verify that all the fields are okay. 3339 unsigned NumNamedMembers = 0; 3340 llvm::SmallVector<FieldDecl*, 32> RecFields; 3341 3342 for (unsigned i = 0; i != NumFields; ++i) { 3343 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3344 assert(FD && "missing field decl"); 3345 3346 // Get the type for the field. 3347 Type *FDTy = FD->getType().getTypePtr(); 3348 3349 if (!FD->isAnonymousStructOrUnion()) { 3350 // Remember all fields written by the user. 3351 RecFields.push_back(FD); 3352 } 3353 3354 // C99 6.7.2.1p2 - A field may not be a function type. 3355 if (FDTy->isFunctionType()) { 3356 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3357 << FD->getDeclName(); 3358 FD->setInvalidDecl(); 3359 EnclosingDecl->setInvalidDecl(); 3360 continue; 3361 } 3362 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3363 if (FDTy->isIncompleteType()) { 3364 if (!Record) { // Incomplete ivar type is always an error. 3365 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3366 diag::err_field_incomplete); 3367 FD->setInvalidDecl(); 3368 EnclosingDecl->setInvalidDecl(); 3369 continue; 3370 } 3371 if (i != NumFields-1 || // ... that the last member ... 3372 !Record->isStruct() || // ... of a structure ... 3373 !FDTy->isArrayType()) { //... may have incomplete array type. 3374 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3375 diag::err_field_incomplete); 3376 FD->setInvalidDecl(); 3377 EnclosingDecl->setInvalidDecl(); 3378 continue; 3379 } 3380 if (NumNamedMembers < 1) { //... must have more than named member ... 3381 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3382 << FD->getDeclName(); 3383 FD->setInvalidDecl(); 3384 EnclosingDecl->setInvalidDecl(); 3385 continue; 3386 } 3387 // Okay, we have a legal flexible array member at the end of the struct. 3388 if (Record) 3389 Record->setHasFlexibleArrayMember(true); 3390 } 3391 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3392 /// field of another structure or the element of an array. 3393 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3394 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3395 // If this is a member of a union, then entire union becomes "flexible". 3396 if (Record && Record->isUnion()) { 3397 Record->setHasFlexibleArrayMember(true); 3398 } else { 3399 // If this is a struct/class and this is not the last element, reject 3400 // it. Note that GCC supports variable sized arrays in the middle of 3401 // structures. 3402 if (i != NumFields-1) { 3403 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3404 << FD->getDeclName(); 3405 FD->setInvalidDecl(); 3406 EnclosingDecl->setInvalidDecl(); 3407 continue; 3408 } 3409 // We support flexible arrays at the end of structs in other structs 3410 // as an extension. 3411 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3412 << FD->getDeclName(); 3413 if (Record) 3414 Record->setHasFlexibleArrayMember(true); 3415 } 3416 } 3417 } 3418 /// A field cannot be an Objective-c object 3419 if (FDTy->isObjCInterfaceType()) { 3420 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3421 << FD->getDeclName(); 3422 FD->setInvalidDecl(); 3423 EnclosingDecl->setInvalidDecl(); 3424 continue; 3425 } 3426 // Keep track of the number of named members. 3427 if (FD->getIdentifier()) 3428 ++NumNamedMembers; 3429 } 3430 3431 // Okay, we successfully defined 'Record'. 3432 if (Record) { 3433 Record->completeDefinition(Context); 3434 } else { 3435 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3436 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3437 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3438 // Must enforce the rule that ivars in the base classes may not be 3439 // duplicates. 3440 if (ID->getSuperClass()) { 3441 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3442 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3443 ObjCIvarDecl* Ivar = (*IVI); 3444 IdentifierInfo *II = Ivar->getIdentifier(); 3445 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3446 if (prevIvar) { 3447 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3448 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3449 } 3450 } 3451 } 3452 } 3453 else if (ObjCImplementationDecl *IMPDecl = 3454 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3455 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3456 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3457 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3458 } 3459 } 3460 3461 if (Attr) 3462 ProcessDeclAttributeList(Record, Attr); 3463} 3464 3465Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3466 DeclTy *lastEnumConst, 3467 SourceLocation IdLoc, IdentifierInfo *Id, 3468 SourceLocation EqualLoc, ExprTy *val) { 3469 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3470 EnumConstantDecl *LastEnumConst = 3471 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3472 Expr *Val = static_cast<Expr*>(val); 3473 3474 // The scope passed in may not be a decl scope. Zip up the scope tree until 3475 // we find one that is. 3476 S = getNonFieldDeclScope(S); 3477 3478 // Verify that there isn't already something declared with this name in this 3479 // scope. 3480 Decl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3481 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3482 // Maybe we will complain about the shadowed template parameter. 3483 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3484 // Just pretend that we didn't see the previous declaration. 3485 PrevDecl = 0; 3486 } 3487 3488 if (PrevDecl) { 3489 // When in C++, we may get a TagDecl with the same name; in this case the 3490 // enum constant will 'hide' the tag. 3491 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3492 "Received TagDecl when not in C++!"); 3493 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3494 if (isa<EnumConstantDecl>(PrevDecl)) 3495 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3496 else 3497 Diag(IdLoc, diag::err_redefinition) << Id; 3498 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3499 delete Val; 3500 return 0; 3501 } 3502 } 3503 3504 llvm::APSInt EnumVal(32); 3505 QualType EltTy; 3506 if (Val) { 3507 // Make sure to promote the operand type to int. 3508 UsualUnaryConversions(Val); 3509 3510 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3511 SourceLocation ExpLoc; 3512 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3513 delete Val; 3514 Val = 0; // Just forget about it. 3515 } else { 3516 EltTy = Val->getType(); 3517 } 3518 } 3519 3520 if (!Val) { 3521 if (LastEnumConst) { 3522 // Assign the last value + 1. 3523 EnumVal = LastEnumConst->getInitVal(); 3524 ++EnumVal; 3525 3526 // Check for overflow on increment. 3527 if (EnumVal < LastEnumConst->getInitVal()) 3528 Diag(IdLoc, diag::warn_enum_value_overflow); 3529 3530 EltTy = LastEnumConst->getType(); 3531 } else { 3532 // First value, set to zero. 3533 EltTy = Context.IntTy; 3534 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3535 } 3536 } 3537 3538 EnumConstantDecl *New = 3539 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3540 Val, EnumVal); 3541 3542 // Register this decl in the current scope stack. 3543 PushOnScopeChains(New, S); 3544 3545 return New; 3546} 3547 3548// FIXME: For consistency with ActOnFields(), we should have the parser 3549// pass in the source location for the left/right braces. 3550void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3551 DeclTy **Elements, unsigned NumElements) { 3552 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3553 QualType EnumType = Context.getTypeDeclType(Enum); 3554 3555 // TODO: If the result value doesn't fit in an int, it must be a long or long 3556 // long value. ISO C does not support this, but GCC does as an extension, 3557 // emit a warning. 3558 unsigned IntWidth = Context.Target.getIntWidth(); 3559 3560 // Verify that all the values are okay, compute the size of the values, and 3561 // reverse the list. 3562 unsigned NumNegativeBits = 0; 3563 unsigned NumPositiveBits = 0; 3564 3565 // Keep track of whether all elements have type int. 3566 bool AllElementsInt = true; 3567 3568 for (unsigned i = 0; i != NumElements; ++i) { 3569 EnumConstantDecl *ECD = 3570 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3571 if (!ECD) continue; // Already issued a diagnostic. 3572 3573 // If the enum value doesn't fit in an int, emit an extension warning. 3574 const llvm::APSInt &InitVal = ECD->getInitVal(); 3575 assert(InitVal.getBitWidth() >= IntWidth && 3576 "Should have promoted value to int"); 3577 if (InitVal.getBitWidth() > IntWidth) { 3578 llvm::APSInt V(InitVal); 3579 V.trunc(IntWidth); 3580 V.extend(InitVal.getBitWidth()); 3581 if (V != InitVal) 3582 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3583 << InitVal.toString(10); 3584 } 3585 3586 // Keep track of the size of positive and negative values. 3587 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3588 NumPositiveBits = std::max(NumPositiveBits, 3589 (unsigned)InitVal.getActiveBits()); 3590 else 3591 NumNegativeBits = std::max(NumNegativeBits, 3592 (unsigned)InitVal.getMinSignedBits()); 3593 3594 // Keep track of whether every enum element has type int (very commmon). 3595 if (AllElementsInt) 3596 AllElementsInt = ECD->getType() == Context.IntTy; 3597 } 3598 3599 // Figure out the type that should be used for this enum. 3600 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3601 QualType BestType; 3602 unsigned BestWidth; 3603 3604 if (NumNegativeBits) { 3605 // If there is a negative value, figure out the smallest integer type (of 3606 // int/long/longlong) that fits. 3607 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3608 BestType = Context.IntTy; 3609 BestWidth = IntWidth; 3610 } else { 3611 BestWidth = Context.Target.getLongWidth(); 3612 3613 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3614 BestType = Context.LongTy; 3615 else { 3616 BestWidth = Context.Target.getLongLongWidth(); 3617 3618 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3619 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3620 BestType = Context.LongLongTy; 3621 } 3622 } 3623 } else { 3624 // If there is no negative value, figure out which of uint, ulong, ulonglong 3625 // fits. 3626 if (NumPositiveBits <= IntWidth) { 3627 BestType = Context.UnsignedIntTy; 3628 BestWidth = IntWidth; 3629 } else if (NumPositiveBits <= 3630 (BestWidth = Context.Target.getLongWidth())) { 3631 BestType = Context.UnsignedLongTy; 3632 } else { 3633 BestWidth = Context.Target.getLongLongWidth(); 3634 assert(NumPositiveBits <= BestWidth && 3635 "How could an initializer get larger than ULL?"); 3636 BestType = Context.UnsignedLongLongTy; 3637 } 3638 } 3639 3640 // Loop over all of the enumerator constants, changing their types to match 3641 // the type of the enum if needed. 3642 for (unsigned i = 0; i != NumElements; ++i) { 3643 EnumConstantDecl *ECD = 3644 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3645 if (!ECD) continue; // Already issued a diagnostic. 3646 3647 // Standard C says the enumerators have int type, but we allow, as an 3648 // extension, the enumerators to be larger than int size. If each 3649 // enumerator value fits in an int, type it as an int, otherwise type it the 3650 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3651 // that X has type 'int', not 'unsigned'. 3652 if (ECD->getType() == Context.IntTy) { 3653 // Make sure the init value is signed. 3654 llvm::APSInt IV = ECD->getInitVal(); 3655 IV.setIsSigned(true); 3656 ECD->setInitVal(IV); 3657 3658 if (getLangOptions().CPlusPlus) 3659 // C++ [dcl.enum]p4: Following the closing brace of an 3660 // enum-specifier, each enumerator has the type of its 3661 // enumeration. 3662 ECD->setType(EnumType); 3663 continue; // Already int type. 3664 } 3665 3666 // Determine whether the value fits into an int. 3667 llvm::APSInt InitVal = ECD->getInitVal(); 3668 bool FitsInInt; 3669 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3670 FitsInInt = InitVal.getActiveBits() < IntWidth; 3671 else 3672 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3673 3674 // If it fits into an integer type, force it. Otherwise force it to match 3675 // the enum decl type. 3676 QualType NewTy; 3677 unsigned NewWidth; 3678 bool NewSign; 3679 if (FitsInInt) { 3680 NewTy = Context.IntTy; 3681 NewWidth = IntWidth; 3682 NewSign = true; 3683 } else if (ECD->getType() == BestType) { 3684 // Already the right type! 3685 if (getLangOptions().CPlusPlus) 3686 // C++ [dcl.enum]p4: Following the closing brace of an 3687 // enum-specifier, each enumerator has the type of its 3688 // enumeration. 3689 ECD->setType(EnumType); 3690 continue; 3691 } else { 3692 NewTy = BestType; 3693 NewWidth = BestWidth; 3694 NewSign = BestType->isSignedIntegerType(); 3695 } 3696 3697 // Adjust the APSInt value. 3698 InitVal.extOrTrunc(NewWidth); 3699 InitVal.setIsSigned(NewSign); 3700 ECD->setInitVal(InitVal); 3701 3702 // Adjust the Expr initializer and type. 3703 if (ECD->getInitExpr()) 3704 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3705 /*isLvalue=*/false)); 3706 if (getLangOptions().CPlusPlus) 3707 // C++ [dcl.enum]p4: Following the closing brace of an 3708 // enum-specifier, each enumerator has the type of its 3709 // enumeration. 3710 ECD->setType(EnumType); 3711 else 3712 ECD->setType(NewTy); 3713 } 3714 3715 Enum->completeDefinition(Context, BestType); 3716} 3717 3718Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3719 ExprArg expr) { 3720 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3721 3722 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3723} 3724 3725 3726void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3727 ExprTy *alignment, SourceLocation PragmaLoc, 3728 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3729 Expr *Alignment = static_cast<Expr *>(alignment); 3730 3731 // If specified then alignment must be a "small" power of two. 3732 unsigned AlignmentVal = 0; 3733 if (Alignment) { 3734 llvm::APSInt Val; 3735 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3736 !Val.isPowerOf2() || 3737 Val.getZExtValue() > 16) { 3738 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3739 delete Alignment; 3740 return; // Ignore 3741 } 3742 3743 AlignmentVal = (unsigned) Val.getZExtValue(); 3744 } 3745 3746 switch (Kind) { 3747 case Action::PPK_Default: // pack([n]) 3748 PackContext.setAlignment(AlignmentVal); 3749 break; 3750 3751 case Action::PPK_Show: // pack(show) 3752 // Show the current alignment, making sure to show the right value 3753 // for the default. 3754 AlignmentVal = PackContext.getAlignment(); 3755 // FIXME: This should come from the target. 3756 if (AlignmentVal == 0) 3757 AlignmentVal = 8; 3758 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3759 break; 3760 3761 case Action::PPK_Push: // pack(push [, id] [, [n]) 3762 PackContext.push(Name); 3763 // Set the new alignment if specified. 3764 if (Alignment) 3765 PackContext.setAlignment(AlignmentVal); 3766 break; 3767 3768 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3769 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3770 // "#pragma pack(pop, identifier, n) is undefined" 3771 if (Alignment && Name) 3772 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3773 3774 // Do the pop. 3775 if (!PackContext.pop(Name)) { 3776 // If a name was specified then failure indicates the name 3777 // wasn't found. Otherwise failure indicates the stack was 3778 // empty. 3779 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3780 << (Name ? "no record matching name" : "stack empty"); 3781 3782 // FIXME: Warn about popping named records as MSVC does. 3783 } else { 3784 // Pop succeeded, set the new alignment if specified. 3785 if (Alignment) 3786 PackContext.setAlignment(AlignmentVal); 3787 } 3788 break; 3789 3790 default: 3791 assert(0 && "Invalid #pragma pack kind."); 3792 } 3793} 3794 3795bool PragmaPackStack::pop(IdentifierInfo *Name) { 3796 if (Stack.empty()) 3797 return false; 3798 3799 // If name is empty just pop top. 3800 if (!Name) { 3801 Alignment = Stack.back().first; 3802 Stack.pop_back(); 3803 return true; 3804 } 3805 3806 // Otherwise, find the named record. 3807 for (unsigned i = Stack.size(); i != 0; ) { 3808 --i; 3809 if (Stack[i].second == Name) { 3810 // Found it, pop up to and including this record. 3811 Alignment = Stack[i].first; 3812 Stack.erase(Stack.begin() + i, Stack.end()); 3813 return true; 3814 } 3815 } 3816 3817 return false; 3818} 3819