SemaDecl.cpp revision 72de8493647493a81b3d73d39369e5231393a1d5
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/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31 32using namespace clang; 33 34Sema::TypeTy *Sema::isTypeName(IdentifierInfo &II, Scope *S, 35 const CXXScopeSpec *SS) { 36 DeclContext *DC = 0; 37 if (SS) { 38 if (SS->isInvalid()) 39 return 0; 40 DC = static_cast<DeclContext*>(SS->getScopeRep()); 41 } 42 LookupResult Result = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC, false); 43 44 Decl *IIDecl = 0; 45 switch (Result.getKind()) { 46 case LookupResult::NotFound: 47 case LookupResult::FoundOverloaded: 48 case LookupResult::AmbiguousBaseSubobjectTypes: 49 case LookupResult::AmbiguousBaseSubobjects: 50 // FIXME: In the event of an ambiguous lookup, we could visit all of 51 // the entities found to determine whether they are all types. This 52 // might provide better diagnostics. 53 return 0; 54 55 case LookupResult::Found: 56 IIDecl = Result.getAsDecl(); 57 break; 58 } 59 60 if (isa<TypedefDecl>(IIDecl) || 61 isa<ObjCInterfaceDecl>(IIDecl) || 62 isa<TagDecl>(IIDecl) || 63 isa<TemplateTypeParmDecl>(IIDecl)) 64 return IIDecl; 65 return 0; 66} 67 68DeclContext *Sema::getContainingDC(DeclContext *DC) { 69 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 70 // A C++ out-of-line method will return to the file declaration context. 71 if (MD->isOutOfLineDefinition()) 72 return MD->getLexicalDeclContext(); 73 74 // A C++ inline method is parsed *after* the topmost class it was declared in 75 // is fully parsed (it's "complete"). 76 // The parsing of a C++ inline method happens at the declaration context of 77 // the topmost (non-nested) class it is lexically declared in. 78 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 79 DC = MD->getParent(); 80 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 81 DC = RD; 82 83 // Return the declaration context of the topmost class the inline method is 84 // declared in. 85 return DC; 86 } 87 88 if (isa<ObjCMethodDecl>(DC)) 89 return Context.getTranslationUnitDecl(); 90 91 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(DC)) 92 return SD->getLexicalDeclContext(); 93 94 return DC->getLexicalParent(); 95} 96 97void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 98 assert(getContainingDC(DC) == CurContext && 99 "The next DeclContext should be lexically contained in the current one."); 100 CurContext = DC; 101 S->setEntity(DC); 102} 103 104void Sema::PopDeclContext() { 105 assert(CurContext && "DeclContext imbalance!"); 106 107 CurContext = getContainingDC(CurContext); 108} 109 110/// Add this decl to the scope shadowed decl chains. 111void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 112 // Move up the scope chain until we find the nearest enclosing 113 // non-transparent context. The declaration will be introduced into this 114 // scope. 115 while (S->getEntity() && 116 ((DeclContext *)S->getEntity())->isTransparentContext()) 117 S = S->getParent(); 118 119 S->AddDecl(D); 120 121 // Add scoped declarations into their context, so that they can be 122 // found later. Declarations without a context won't be inserted 123 // into any context. 124 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D)) 125 CurContext->addDecl(SD); 126 127 // C++ [basic.scope]p4: 128 // -- exactly one declaration shall declare a class name or 129 // enumeration name that is not a typedef name and the other 130 // declarations shall all refer to the same object or 131 // enumerator, or all refer to functions and function templates; 132 // in this case the class name or enumeration name is hidden. 133 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 134 // We are pushing the name of a tag (enum or class). 135 if (CurContext->getLookupContext() 136 == TD->getDeclContext()->getLookupContext()) { 137 // We're pushing the tag into the current context, which might 138 // require some reshuffling in the identifier resolver. 139 IdentifierResolver::iterator 140 I = IdResolver.begin(TD->getDeclName(), CurContext, 141 false/*LookInParentCtx*/), 142 IEnd = IdResolver.end(); 143 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 144 NamedDecl *PrevDecl = *I; 145 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 146 PrevDecl = *I, ++I) { 147 if (TD->declarationReplaces(*I)) { 148 // This is a redeclaration. Remove it from the chain and 149 // break out, so that we'll add in the shadowed 150 // declaration. 151 S->RemoveDecl(*I); 152 if (PrevDecl == *I) { 153 IdResolver.RemoveDecl(*I); 154 IdResolver.AddDecl(TD); 155 return; 156 } else { 157 IdResolver.RemoveDecl(*I); 158 break; 159 } 160 } 161 } 162 163 // There is already a declaration with the same name in the same 164 // scope, which is not a tag declaration. It must be found 165 // before we find the new declaration, so insert the new 166 // declaration at the end of the chain. 167 IdResolver.AddShadowedDecl(TD, PrevDecl); 168 169 return; 170 } 171 } 172 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 173 // We are pushing the name of a function, which might be an 174 // overloaded name. 175 FunctionDecl *FD = cast<FunctionDecl>(D); 176 DeclContext *DC = FD->getDeclContext()->getLookupContext(); 177 IdentifierResolver::iterator Redecl 178 = std::find_if(IdResolver.begin(FD->getDeclName(), DC, 179 false/*LookInParentCtx*/), 180 IdResolver.end(), 181 std::bind1st(std::mem_fun(&ScopedDecl::declarationReplaces), 182 FD)); 183 if (Redecl != IdResolver.end()) { 184 // There is already a declaration of a function on our 185 // IdResolver chain. Replace it with this declaration. 186 S->RemoveDecl(*Redecl); 187 IdResolver.RemoveDecl(*Redecl); 188 } 189 } 190 191 IdResolver.AddDecl(D); 192} 193 194void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 195 if (S->decl_empty()) return; 196 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 197 "Scope shouldn't contain decls!"); 198 199 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 200 I != E; ++I) { 201 Decl *TmpD = static_cast<Decl*>(*I); 202 assert(TmpD && "This decl didn't get pushed??"); 203 204 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 205 NamedDecl *D = cast<NamedDecl>(TmpD); 206 207 if (!D->getDeclName()) continue; 208 209 // Remove this name from our lexical scope. 210 IdResolver.RemoveDecl(D); 211 } 212} 213 214/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 215/// return 0 if one not found. 216ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 217 // The third "scope" argument is 0 since we aren't enabling lazy built-in 218 // creation from this context. 219 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 220 221 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 222} 223 224/// getNonFieldDeclScope - Retrieves the innermost scope, starting 225/// from S, where a non-field would be declared. This routine copes 226/// with the difference between C and C++ scoping rules in structs and 227/// unions. For example, the following code is well-formed in C but 228/// ill-formed in C++: 229/// @code 230/// struct S6 { 231/// enum { BAR } e; 232/// }; 233/// 234/// void test_S6() { 235/// struct S6 a; 236/// a.e = BAR; 237/// } 238/// @endcode 239/// For the declaration of BAR, this routine will return a different 240/// scope. The scope S will be the scope of the unnamed enumeration 241/// within S6. In C++, this routine will return the scope associated 242/// with S6, because the enumeration's scope is a transparent 243/// context but structures can contain non-field names. In C, this 244/// routine will return the translation unit scope, since the 245/// enumeration's scope is a transparent context and structures cannot 246/// contain non-field names. 247Scope *Sema::getNonFieldDeclScope(Scope *S) { 248 while (((S->getFlags() & Scope::DeclScope) == 0) || 249 (S->getEntity() && 250 ((DeclContext *)S->getEntity())->isTransparentContext()) || 251 (S->isClassScope() && !getLangOptions().CPlusPlus)) 252 S = S->getParent(); 253 return S; 254} 255 256/// LookupDecl - Look up the inner-most declaration in the specified 257/// namespace. NamespaceNameOnly - during lookup only namespace names 258/// are considered as required in C++ [basic.lookup.udir] 3.4.6.p1 259/// 'When looking up a namespace-name in a using-directive or 260/// namespace-alias-definition, only namespace names are considered.' 261/// 262/// Note: The use of this routine is deprecated. Please use 263/// LookupName, LookupQualifiedName, or LookupParsedName instead. 264Sema::LookupResult 265Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 266 const DeclContext *LookupCtx, 267 bool enableLazyBuiltinCreation, 268 bool LookInParent, 269 bool NamespaceNameOnly) { 270 LookupCriteria::NameKind Kind; 271 if (NSI == Decl::IDNS_Ordinary) { 272 if (NamespaceNameOnly) 273 Kind = LookupCriteria::Namespace; 274 else 275 Kind = LookupCriteria::Ordinary; 276 } else if (NSI == Decl::IDNS_Tag) 277 Kind = LookupCriteria::Tag; 278 else { 279 assert(NSI == Decl::IDNS_Member &&"Unable to grok LookupDecl NSI argument"); 280 Kind = LookupCriteria::Member; 281 } 282 283 if (LookupCtx) 284 return LookupQualifiedName(const_cast<DeclContext *>(LookupCtx), Name, 285 LookupCriteria(Kind, !LookInParent, 286 getLangOptions().CPlusPlus)); 287 288 // Unqualified lookup 289 return LookupName(S, Name, 290 LookupCriteria(Kind, !LookInParent, 291 getLangOptions().CPlusPlus)); 292} 293 294void Sema::InitBuiltinVaListType() { 295 if (!Context.getBuiltinVaListType().isNull()) 296 return; 297 298 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 299 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 300 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 301 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 302} 303 304/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 305/// lazily create a decl for it. 306ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 307 Scope *S) { 308 Builtin::ID BID = (Builtin::ID)bid; 309 310 if (Context.BuiltinInfo.hasVAListUse(BID)) 311 InitBuiltinVaListType(); 312 313 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 314 FunctionDecl *New = FunctionDecl::Create(Context, 315 Context.getTranslationUnitDecl(), 316 SourceLocation(), II, R, 317 FunctionDecl::Extern, false, 0); 318 319 // Create Decl objects for each parameter, adding them to the 320 // FunctionDecl. 321 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 322 llvm::SmallVector<ParmVarDecl*, 16> Params; 323 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 324 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 325 FT->getArgType(i), VarDecl::None, 0, 326 0)); 327 New->setParams(Context, &Params[0], Params.size()); 328 } 329 330 331 332 // TUScope is the translation-unit scope to insert this function into. 333 // FIXME: This is hideous. We need to teach PushOnScopeChains to 334 // relate Scopes to DeclContexts, and probably eliminate CurContext 335 // entirely, but we're not there yet. 336 DeclContext *SavedContext = CurContext; 337 CurContext = Context.getTranslationUnitDecl(); 338 PushOnScopeChains(New, TUScope); 339 CurContext = SavedContext; 340 return New; 341} 342 343/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 344/// everything from the standard library is defined. 345NamespaceDecl *Sema::GetStdNamespace() { 346 if (!StdNamespace) { 347 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 348 DeclContext *Global = Context.getTranslationUnitDecl(); 349 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Ordinary, 350 0, Global, /*enableLazyBuiltinCreation=*/false); 351 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 352 } 353 return StdNamespace; 354} 355 356/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 357/// and scope as a previous declaration 'Old'. Figure out how to resolve this 358/// situation, merging decls or emitting diagnostics as appropriate. 359/// 360TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 361 bool objc_types = false; 362 // Allow multiple definitions for ObjC built-in typedefs. 363 // FIXME: Verify the underlying types are equivalent! 364 if (getLangOptions().ObjC1) { 365 const IdentifierInfo *TypeID = New->getIdentifier(); 366 switch (TypeID->getLength()) { 367 default: break; 368 case 2: 369 if (!TypeID->isStr("id")) 370 break; 371 Context.setObjCIdType(New); 372 objc_types = true; 373 break; 374 case 5: 375 if (!TypeID->isStr("Class")) 376 break; 377 Context.setObjCClassType(New); 378 objc_types = true; 379 return New; 380 case 3: 381 if (!TypeID->isStr("SEL")) 382 break; 383 Context.setObjCSelType(New); 384 objc_types = true; 385 return New; 386 case 8: 387 if (!TypeID->isStr("Protocol")) 388 break; 389 Context.setObjCProtoType(New->getUnderlyingType()); 390 objc_types = true; 391 return New; 392 } 393 // Fall through - the typedef name was not a builtin type. 394 } 395 // Verify the old decl was also a typedef. 396 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 397 if (!Old) { 398 Diag(New->getLocation(), diag::err_redefinition_different_kind) 399 << New->getDeclName(); 400 if (!objc_types) 401 Diag(OldD->getLocation(), diag::note_previous_definition); 402 return New; 403 } 404 405 // If the typedef types are not identical, reject them in all languages and 406 // with any extensions enabled. 407 if (Old->getUnderlyingType() != New->getUnderlyingType() && 408 Context.getCanonicalType(Old->getUnderlyingType()) != 409 Context.getCanonicalType(New->getUnderlyingType())) { 410 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 411 << New->getUnderlyingType() << Old->getUnderlyingType(); 412 if (!objc_types) 413 Diag(Old->getLocation(), diag::note_previous_definition); 414 return New; 415 } 416 if (objc_types) return New; 417 if (getLangOptions().Microsoft) return New; 418 419 // C++ [dcl.typedef]p2: 420 // In a given non-class scope, a typedef specifier can be used to 421 // redefine the name of any type declared in that scope to refer 422 // to the type to which it already refers. 423 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 424 return New; 425 426 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 427 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 428 // *either* declaration is in a system header. The code below implements 429 // this adhoc compatibility rule. FIXME: The following code will not 430 // work properly when compiling ".i" files (containing preprocessed output). 431 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 432 SourceManager &SrcMgr = Context.getSourceManager(); 433 if (SrcMgr.isInSystemHeader(Old->getLocation())) 434 return New; 435 if (SrcMgr.isInSystemHeader(New->getLocation())) 436 return New; 437 } 438 439 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 440 Diag(Old->getLocation(), diag::note_previous_definition); 441 return New; 442} 443 444/// DeclhasAttr - returns true if decl Declaration already has the target 445/// attribute. 446static bool DeclHasAttr(const Decl *decl, const Attr *target) { 447 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 448 if (attr->getKind() == target->getKind()) 449 return true; 450 451 return false; 452} 453 454/// MergeAttributes - append attributes from the Old decl to the New one. 455static void MergeAttributes(Decl *New, Decl *Old) { 456 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 457 458 while (attr) { 459 tmp = attr; 460 attr = attr->getNext(); 461 462 if (!DeclHasAttr(New, tmp)) { 463 tmp->setInherited(true); 464 New->addAttr(tmp); 465 } else { 466 tmp->setNext(0); 467 delete(tmp); 468 } 469 } 470 471 Old->invalidateAttrs(); 472} 473 474/// MergeFunctionDecl - We just parsed a function 'New' from 475/// declarator D which has the same name and scope as a previous 476/// declaration 'Old'. Figure out how to resolve this situation, 477/// merging decls or emitting diagnostics as appropriate. 478/// Redeclaration will be set true if this New is a redeclaration OldD. 479/// 480/// In C++, New and Old must be declarations that are not 481/// overloaded. Use IsOverload to determine whether New and Old are 482/// overloaded, and to select the Old declaration that New should be 483/// merged with. 484FunctionDecl * 485Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 486 assert(!isa<OverloadedFunctionDecl>(OldD) && 487 "Cannot merge with an overloaded function declaration"); 488 489 Redeclaration = false; 490 // Verify the old decl was also a function. 491 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 492 if (!Old) { 493 Diag(New->getLocation(), diag::err_redefinition_different_kind) 494 << New->getDeclName(); 495 Diag(OldD->getLocation(), diag::note_previous_definition); 496 return New; 497 } 498 499 // Determine whether the previous declaration was a definition, 500 // implicit declaration, or a declaration. 501 diag::kind PrevDiag; 502 if (Old->isThisDeclarationADefinition()) 503 PrevDiag = diag::note_previous_definition; 504 else if (Old->isImplicit()) 505 PrevDiag = diag::note_previous_implicit_declaration; 506 else 507 PrevDiag = diag::note_previous_declaration; 508 509 QualType OldQType = Context.getCanonicalType(Old->getType()); 510 QualType NewQType = Context.getCanonicalType(New->getType()); 511 512 if (getLangOptions().CPlusPlus) { 513 // (C++98 13.1p2): 514 // Certain function declarations cannot be overloaded: 515 // -- Function declarations that differ only in the return type 516 // cannot be overloaded. 517 QualType OldReturnType 518 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 519 QualType NewReturnType 520 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 521 if (OldReturnType != NewReturnType) { 522 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 523 Diag(Old->getLocation(), PrevDiag); 524 Redeclaration = true; 525 return New; 526 } 527 528 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 529 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 530 if (OldMethod && NewMethod) { 531 // -- Member function declarations with the same name and the 532 // same parameter types cannot be overloaded if any of them 533 // is a static member function declaration. 534 if (OldMethod->isStatic() || NewMethod->isStatic()) { 535 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 536 Diag(Old->getLocation(), PrevDiag); 537 return New; 538 } 539 540 // C++ [class.mem]p1: 541 // [...] A member shall not be declared twice in the 542 // member-specification, except that a nested class or member 543 // class template can be declared and then later defined. 544 if (OldMethod->getLexicalDeclContext() == 545 NewMethod->getLexicalDeclContext()) { 546 unsigned NewDiag; 547 if (isa<CXXConstructorDecl>(OldMethod)) 548 NewDiag = diag::err_constructor_redeclared; 549 else if (isa<CXXDestructorDecl>(NewMethod)) 550 NewDiag = diag::err_destructor_redeclared; 551 else if (isa<CXXConversionDecl>(NewMethod)) 552 NewDiag = diag::err_conv_function_redeclared; 553 else 554 NewDiag = diag::err_member_redeclared; 555 556 Diag(New->getLocation(), NewDiag); 557 Diag(Old->getLocation(), PrevDiag); 558 } 559 } 560 561 // (C++98 8.3.5p3): 562 // All declarations for a function shall agree exactly in both the 563 // return type and the parameter-type-list. 564 if (OldQType == NewQType) { 565 // We have a redeclaration. 566 MergeAttributes(New, Old); 567 Redeclaration = true; 568 return MergeCXXFunctionDecl(New, Old); 569 } 570 571 // Fall through for conflicting redeclarations and redefinitions. 572 } 573 574 // C: Function types need to be compatible, not identical. This handles 575 // duplicate function decls like "void f(int); void f(enum X);" properly. 576 if (!getLangOptions().CPlusPlus && 577 Context.typesAreCompatible(OldQType, NewQType)) { 578 MergeAttributes(New, Old); 579 Redeclaration = true; 580 return New; 581 } 582 583 // A function that has already been declared has been redeclared or defined 584 // with a different type- show appropriate diagnostic 585 586 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 587 // TODO: This is totally simplistic. It should handle merging functions 588 // together etc, merging extern int X; int X; ... 589 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 590 Diag(Old->getLocation(), PrevDiag); 591 return New; 592} 593 594/// Predicate for C "tentative" external object definitions (C99 6.9.2). 595static bool isTentativeDefinition(VarDecl *VD) { 596 if (VD->isFileVarDecl()) 597 return (!VD->getInit() && 598 (VD->getStorageClass() == VarDecl::None || 599 VD->getStorageClass() == VarDecl::Static)); 600 return false; 601} 602 603/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 604/// when dealing with C "tentative" external object definitions (C99 6.9.2). 605void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 606 bool VDIsTentative = isTentativeDefinition(VD); 607 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 608 609 // FIXME: I don't think this will actually see all of the 610 // redefinitions. Can't we check this property on-the-fly? 611 for (IdentifierResolver::iterator 612 I = IdResolver.begin(VD->getIdentifier(), 613 VD->getDeclContext(), false/*LookInParentCtx*/), 614 E = IdResolver.end(); I != E; ++I) { 615 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 616 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 617 618 // Handle the following case: 619 // int a[10]; 620 // int a[]; - the code below makes sure we set the correct type. 621 // int a[11]; - this is an error, size isn't 10. 622 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 623 OldDecl->getType()->isConstantArrayType()) 624 VD->setType(OldDecl->getType()); 625 626 // Check for "tentative" definitions. We can't accomplish this in 627 // MergeVarDecl since the initializer hasn't been attached. 628 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 629 continue; 630 631 // Handle __private_extern__ just like extern. 632 if (OldDecl->getStorageClass() != VarDecl::Extern && 633 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 634 VD->getStorageClass() != VarDecl::Extern && 635 VD->getStorageClass() != VarDecl::PrivateExtern) { 636 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 637 Diag(OldDecl->getLocation(), diag::note_previous_definition); 638 } 639 } 640 } 641} 642 643/// MergeVarDecl - We just parsed a variable 'New' which has the same name 644/// and scope as a previous declaration 'Old'. Figure out how to resolve this 645/// situation, merging decls or emitting diagnostics as appropriate. 646/// 647/// Tentative definition rules (C99 6.9.2p2) are checked by 648/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 649/// definitions here, since the initializer hasn't been attached. 650/// 651VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 652 // Verify the old decl was also a variable. 653 VarDecl *Old = dyn_cast<VarDecl>(OldD); 654 if (!Old) { 655 Diag(New->getLocation(), diag::err_redefinition_different_kind) 656 << New->getDeclName(); 657 Diag(OldD->getLocation(), diag::note_previous_definition); 658 return New; 659 } 660 661 MergeAttributes(New, Old); 662 663 // Verify the types match. 664 QualType OldCType = Context.getCanonicalType(Old->getType()); 665 QualType NewCType = Context.getCanonicalType(New->getType()); 666 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 667 Diag(New->getLocation(), diag::err_redefinition_different_type) 668 << New->getDeclName(); 669 Diag(Old->getLocation(), diag::note_previous_definition); 670 return New; 671 } 672 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 673 if (New->getStorageClass() == VarDecl::Static && 674 (Old->getStorageClass() == VarDecl::None || 675 Old->getStorageClass() == VarDecl::Extern)) { 676 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 677 Diag(Old->getLocation(), diag::note_previous_definition); 678 return New; 679 } 680 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 681 if (New->getStorageClass() != VarDecl::Static && 682 Old->getStorageClass() == VarDecl::Static) { 683 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 684 Diag(Old->getLocation(), diag::note_previous_definition); 685 return New; 686 } 687 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 688 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 689 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 690 Diag(Old->getLocation(), diag::note_previous_definition); 691 } 692 return New; 693} 694 695/// CheckParmsForFunctionDef - Check that the parameters of the given 696/// function are appropriate for the definition of a function. This 697/// takes care of any checks that cannot be performed on the 698/// declaration itself, e.g., that the types of each of the function 699/// parameters are complete. 700bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 701 bool HasInvalidParm = false; 702 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 703 ParmVarDecl *Param = FD->getParamDecl(p); 704 705 // C99 6.7.5.3p4: the parameters in a parameter type list in a 706 // function declarator that is part of a function definition of 707 // that function shall not have incomplete type. 708 if (Param->getType()->isIncompleteType() && 709 !Param->isInvalidDecl()) { 710 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 711 << Param->getType(); 712 Param->setInvalidDecl(); 713 HasInvalidParm = true; 714 } 715 716 // C99 6.9.1p5: If the declarator includes a parameter type list, the 717 // declaration of each parameter shall include an identifier. 718 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 719 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 720 } 721 722 return HasInvalidParm; 723} 724 725/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 726/// no declarator (e.g. "struct foo;") is parsed. 727Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 728 TagDecl *Tag 729 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 730 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 731 if (!Record->getDeclName() && Record->isDefinition() && 732 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 733 return BuildAnonymousStructOrUnion(S, DS, Record); 734 735 // Microsoft allows unnamed struct/union fields. Don't complain 736 // about them. 737 // FIXME: Should we support Microsoft's extensions in this area? 738 if (Record->getDeclName() && getLangOptions().Microsoft) 739 return Tag; 740 } 741 742 // Permit typedefs without declarators as a Microsoft extension. 743 if (!DS.isMissingDeclaratorOk()) { 744 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 745 Tag && isa<EnumDecl>(Tag)) { 746 Diag(DS.getSourceRange().getBegin(), diag::warn_no_declarators) 747 << DS.getSourceRange(); 748 return Tag; 749 } 750 751 // FIXME: This diagnostic is emitted even when various previous 752 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 753 // DeclSpec has no means of communicating this information, and the 754 // responsible parser functions are quite far apart. 755 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 756 << DS.getSourceRange(); 757 return 0; 758 } 759 760 return Tag; 761} 762 763/// InjectAnonymousStructOrUnionMembers - Inject the members of the 764/// anonymous struct or union AnonRecord into the owning context Owner 765/// and scope S. This routine will be invoked just after we realize 766/// that an unnamed union or struct is actually an anonymous union or 767/// struct, e.g., 768/// 769/// @code 770/// union { 771/// int i; 772/// float f; 773/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 774/// // f into the surrounding scope.x 775/// @endcode 776/// 777/// This routine is recursive, injecting the names of nested anonymous 778/// structs/unions into the owning context and scope as well. 779bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 780 RecordDecl *AnonRecord) { 781 bool Invalid = false; 782 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 783 FEnd = AnonRecord->field_end(); 784 F != FEnd; ++F) { 785 if ((*F)->getDeclName()) { 786 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 787 S, Owner, false, false, false); 788 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 789 // C++ [class.union]p2: 790 // The names of the members of an anonymous union shall be 791 // distinct from the names of any other entity in the 792 // scope in which the anonymous union is declared. 793 unsigned diagKind 794 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 795 : diag::err_anonymous_struct_member_redecl; 796 Diag((*F)->getLocation(), diagKind) 797 << (*F)->getDeclName(); 798 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 799 Invalid = true; 800 } else { 801 // C++ [class.union]p2: 802 // For the purpose of name lookup, after the anonymous union 803 // definition, the members of the anonymous union are 804 // considered to have been defined in the scope in which the 805 // anonymous union is declared. 806 Owner->insert(*F); 807 S->AddDecl(*F); 808 IdResolver.AddDecl(*F); 809 } 810 } else if (const RecordType *InnerRecordType 811 = (*F)->getType()->getAsRecordType()) { 812 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 813 if (InnerRecord->isAnonymousStructOrUnion()) 814 Invalid = Invalid || 815 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 816 } 817 } 818 819 return Invalid; 820} 821 822/// ActOnAnonymousStructOrUnion - Handle the declaration of an 823/// anonymous structure or union. Anonymous unions are a C++ feature 824/// (C++ [class.union]) and a GNU C extension; anonymous structures 825/// are a GNU C and GNU C++ extension. 826Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 827 RecordDecl *Record) { 828 DeclContext *Owner = Record->getDeclContext(); 829 830 // Diagnose whether this anonymous struct/union is an extension. 831 if (Record->isUnion() && !getLangOptions().CPlusPlus) 832 Diag(Record->getLocation(), diag::ext_anonymous_union); 833 else if (!Record->isUnion()) 834 Diag(Record->getLocation(), diag::ext_anonymous_struct); 835 836 // C and C++ require different kinds of checks for anonymous 837 // structs/unions. 838 bool Invalid = false; 839 if (getLangOptions().CPlusPlus) { 840 const char* PrevSpec = 0; 841 // C++ [class.union]p3: 842 // Anonymous unions declared in a named namespace or in the 843 // global namespace shall be declared static. 844 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 845 (isa<TranslationUnitDecl>(Owner) || 846 (isa<NamespaceDecl>(Owner) && 847 cast<NamespaceDecl>(Owner)->getDeclName()))) { 848 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 849 Invalid = true; 850 851 // Recover by adding 'static'. 852 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 853 } 854 // C++ [class.union]p3: 855 // A storage class is not allowed in a declaration of an 856 // anonymous union in a class scope. 857 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 858 isa<RecordDecl>(Owner)) { 859 Diag(DS.getStorageClassSpecLoc(), 860 diag::err_anonymous_union_with_storage_spec); 861 Invalid = true; 862 863 // Recover by removing the storage specifier. 864 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 865 PrevSpec); 866 } 867 868 // C++ [class.union]p2: 869 // The member-specification of an anonymous union shall only 870 // define non-static data members. [Note: nested types and 871 // functions cannot be declared within an anonymous union. ] 872 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 873 MemEnd = Record->decls_end(); 874 Mem != MemEnd; ++Mem) { 875 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 876 // C++ [class.union]p3: 877 // An anonymous union shall not have private or protected 878 // members (clause 11). 879 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 880 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 881 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 882 Invalid = true; 883 } 884 } else if ((*Mem)->isImplicit()) { 885 // Any implicit members are fine. 886 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 887 if (!MemRecord->isAnonymousStructOrUnion() && 888 MemRecord->getDeclName()) { 889 // This is a nested type declaration. 890 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 891 << (int)Record->isUnion(); 892 Invalid = true; 893 } 894 } else { 895 // We have something that isn't a non-static data 896 // member. Complain about it. 897 unsigned DK = diag::err_anonymous_record_bad_member; 898 if (isa<TypeDecl>(*Mem)) 899 DK = diag::err_anonymous_record_with_type; 900 else if (isa<FunctionDecl>(*Mem)) 901 DK = diag::err_anonymous_record_with_function; 902 else if (isa<VarDecl>(*Mem)) 903 DK = diag::err_anonymous_record_with_static; 904 Diag((*Mem)->getLocation(), DK) 905 << (int)Record->isUnion(); 906 Invalid = true; 907 } 908 } 909 } else { 910 // FIXME: Check GNU C semantics 911 if (Record->isUnion() && !Owner->isRecord()) { 912 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 913 << (int)getLangOptions().CPlusPlus; 914 Invalid = true; 915 } 916 } 917 918 if (!Record->isUnion() && !Owner->isRecord()) { 919 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 920 << (int)getLangOptions().CPlusPlus; 921 Invalid = true; 922 } 923 924 // Create a declaration for this anonymous struct/union. 925 ScopedDecl *Anon = 0; 926 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 927 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 928 /*IdentifierInfo=*/0, 929 Context.getTypeDeclType(Record), 930 /*BitWidth=*/0, /*Mutable=*/false, 931 /*PrevDecl=*/0); 932 Anon->setAccess(AS_public); 933 if (getLangOptions().CPlusPlus) 934 FieldCollector->Add(cast<FieldDecl>(Anon)); 935 } else { 936 VarDecl::StorageClass SC; 937 switch (DS.getStorageClassSpec()) { 938 default: assert(0 && "Unknown storage class!"); 939 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 940 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 941 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 942 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 943 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 944 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 945 case DeclSpec::SCS_mutable: 946 // mutable can only appear on non-static class members, so it's always 947 // an error here 948 Diag(Record->getLocation(), diag::err_mutable_nonmember); 949 Invalid = true; 950 SC = VarDecl::None; 951 break; 952 } 953 954 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 955 /*IdentifierInfo=*/0, 956 Context.getTypeDeclType(Record), 957 SC, /*FIXME:LastDeclarator=*/0, 958 DS.getSourceRange().getBegin()); 959 } 960 Anon->setImplicit(); 961 962 // Add the anonymous struct/union object to the current 963 // context. We'll be referencing this object when we refer to one of 964 // its members. 965 Owner->addDecl(Anon); 966 967 // Inject the members of the anonymous struct/union into the owning 968 // context and into the identifier resolver chain for name lookup 969 // purposes. 970 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 971 Invalid = true; 972 973 // Mark this as an anonymous struct/union type. Note that we do not 974 // do this until after we have already checked and injected the 975 // members of this anonymous struct/union type, because otherwise 976 // the members could be injected twice: once by DeclContext when it 977 // builds its lookup table, and once by 978 // InjectAnonymousStructOrUnionMembers. 979 Record->setAnonymousStructOrUnion(true); 980 981 if (Invalid) 982 Anon->setInvalidDecl(); 983 984 return Anon; 985} 986 987bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 988 bool DirectInit) { 989 // Get the type before calling CheckSingleAssignmentConstraints(), since 990 // it can promote the expression. 991 QualType InitType = Init->getType(); 992 993 if (getLangOptions().CPlusPlus) { 994 // FIXME: I dislike this error message. A lot. 995 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 996 return Diag(Init->getSourceRange().getBegin(), 997 diag::err_typecheck_convert_incompatible) 998 << DeclType << Init->getType() << "initializing" 999 << Init->getSourceRange(); 1000 1001 return false; 1002 } 1003 1004 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1005 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1006 InitType, Init, "initializing"); 1007} 1008 1009bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1010 const ArrayType *AT = Context.getAsArrayType(DeclT); 1011 1012 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1013 // C99 6.7.8p14. We have an array of character type with unknown size 1014 // being initialized to a string literal. 1015 llvm::APSInt ConstVal(32); 1016 ConstVal = strLiteral->getByteLength() + 1; 1017 // Return a new array type (C99 6.7.8p22). 1018 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1019 ArrayType::Normal, 0); 1020 } else { 1021 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1022 // C99 6.7.8p14. We have an array of character type with known size. 1023 // FIXME: Avoid truncation for 64-bit length strings. 1024 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1025 Diag(strLiteral->getSourceRange().getBegin(), 1026 diag::warn_initializer_string_for_char_array_too_long) 1027 << strLiteral->getSourceRange(); 1028 } 1029 // Set type from "char *" to "constant array of char". 1030 strLiteral->setType(DeclT); 1031 // For now, we always return false (meaning success). 1032 return false; 1033} 1034 1035StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1036 const ArrayType *AT = Context.getAsArrayType(DeclType); 1037 if (AT && AT->getElementType()->isCharType()) { 1038 return dyn_cast<StringLiteral>(Init); 1039 } 1040 return 0; 1041} 1042 1043bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1044 SourceLocation InitLoc, 1045 DeclarationName InitEntity, 1046 bool DirectInit) { 1047 if (DeclType->isDependentType() || Init->isTypeDependent()) 1048 return false; 1049 1050 // C++ [dcl.init.ref]p1: 1051 // A variable declared to be a T&, that is "reference to type T" 1052 // (8.3.2), shall be initialized by an object, or function, of 1053 // type T or by an object that can be converted into a T. 1054 if (DeclType->isReferenceType()) 1055 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1056 1057 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1058 // of unknown size ("[]") or an object type that is not a variable array type. 1059 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1060 return Diag(InitLoc, diag::err_variable_object_no_init) 1061 << VAT->getSizeExpr()->getSourceRange(); 1062 1063 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1064 if (!InitList) { 1065 // FIXME: Handle wide strings 1066 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1067 return CheckStringLiteralInit(strLiteral, DeclType); 1068 1069 // C++ [dcl.init]p14: 1070 // -- If the destination type is a (possibly cv-qualified) class 1071 // type: 1072 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1073 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1074 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1075 1076 // -- If the initialization is direct-initialization, or if it is 1077 // copy-initialization where the cv-unqualified version of the 1078 // source type is the same class as, or a derived class of, the 1079 // class of the destination, constructors are considered. 1080 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1081 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1082 CXXConstructorDecl *Constructor 1083 = PerformInitializationByConstructor(DeclType, &Init, 1, 1084 InitLoc, Init->getSourceRange(), 1085 InitEntity, 1086 DirectInit? IK_Direct : IK_Copy); 1087 return Constructor == 0; 1088 } 1089 1090 // -- Otherwise (i.e., for the remaining copy-initialization 1091 // cases), user-defined conversion sequences that can 1092 // convert from the source type to the destination type or 1093 // (when a conversion function is used) to a derived class 1094 // thereof are enumerated as described in 13.3.1.4, and the 1095 // best one is chosen through overload resolution 1096 // (13.3). If the conversion cannot be done or is 1097 // ambiguous, the initialization is ill-formed. The 1098 // function selected is called with the initializer 1099 // expression as its argument; if the function is a 1100 // constructor, the call initializes a temporary of the 1101 // destination type. 1102 // FIXME: We're pretending to do copy elision here; return to 1103 // this when we have ASTs for such things. 1104 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1105 return false; 1106 1107 if (InitEntity) 1108 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1109 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1110 << Init->getType() << Init->getSourceRange(); 1111 else 1112 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1113 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1114 << Init->getType() << Init->getSourceRange(); 1115 } 1116 1117 // C99 6.7.8p16. 1118 if (DeclType->isArrayType()) 1119 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1120 << Init->getSourceRange(); 1121 1122 return CheckSingleInitializer(Init, DeclType, DirectInit); 1123 } else if (getLangOptions().CPlusPlus) { 1124 // C++ [dcl.init]p14: 1125 // [...] If the class is an aggregate (8.5.1), and the initializer 1126 // is a brace-enclosed list, see 8.5.1. 1127 // 1128 // Note: 8.5.1 is handled below; here, we diagnose the case where 1129 // we have an initializer list and a destination type that is not 1130 // an aggregate. 1131 // FIXME: In C++0x, this is yet another form of initialization. 1132 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1133 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1134 if (!ClassDecl->isAggregate()) 1135 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1136 << DeclType << Init->getSourceRange(); 1137 } 1138 } 1139 1140 InitListChecker CheckInitList(this, InitList, DeclType); 1141 return CheckInitList.HadError(); 1142} 1143 1144/// GetNameForDeclarator - Determine the full declaration name for the 1145/// given Declarator. 1146DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1147 switch (D.getKind()) { 1148 case Declarator::DK_Abstract: 1149 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1150 return DeclarationName(); 1151 1152 case Declarator::DK_Normal: 1153 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1154 return DeclarationName(D.getIdentifier()); 1155 1156 case Declarator::DK_Constructor: { 1157 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1158 Ty = Context.getCanonicalType(Ty); 1159 return Context.DeclarationNames.getCXXConstructorName(Ty); 1160 } 1161 1162 case Declarator::DK_Destructor: { 1163 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1164 Ty = Context.getCanonicalType(Ty); 1165 return Context.DeclarationNames.getCXXDestructorName(Ty); 1166 } 1167 1168 case Declarator::DK_Conversion: { 1169 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1170 Ty = Context.getCanonicalType(Ty); 1171 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1172 } 1173 1174 case Declarator::DK_Operator: 1175 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1176 return Context.DeclarationNames.getCXXOperatorName( 1177 D.getOverloadedOperator()); 1178 } 1179 1180 assert(false && "Unknown name kind"); 1181 return DeclarationName(); 1182} 1183 1184/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1185/// functions Declaration and Definition are "nearly" matching. This 1186/// heuristic is used to improve diagnostics in the case where an 1187/// out-of-line member function definition doesn't match any 1188/// declaration within the class. 1189static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1190 FunctionDecl *Declaration, 1191 FunctionDecl *Definition) { 1192 if (Declaration->param_size() != Definition->param_size()) 1193 return false; 1194 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1195 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1196 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1197 1198 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1199 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1200 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1201 return false; 1202 } 1203 1204 return true; 1205} 1206 1207Sema::DeclTy * 1208Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1209 bool IsFunctionDefinition) { 1210 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 1211 DeclarationName Name = GetNameForDeclarator(D); 1212 1213 // All of these full declarators require an identifier. If it doesn't have 1214 // one, the ParsedFreeStandingDeclSpec action should be used. 1215 if (!Name) { 1216 if (!D.getInvalidType()) // Reject this if we think it is valid. 1217 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1218 diag::err_declarator_need_ident) 1219 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1220 return 0; 1221 } 1222 1223 // The scope passed in may not be a decl scope. Zip up the scope tree until 1224 // we find one that is. 1225 while ((S->getFlags() & Scope::DeclScope) == 0 || 1226 (S->getFlags() & Scope::TemplateParamScope) != 0) 1227 S = S->getParent(); 1228 1229 DeclContext *DC; 1230 Decl *PrevDecl; 1231 ScopedDecl *New; 1232 bool InvalidDecl = false; 1233 1234 // See if this is a redefinition of a variable in the same scope. 1235 if (!D.getCXXScopeSpec().isSet()) { 1236 DC = CurContext; 1237 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1238 } else { // Something like "int foo::x;" 1239 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1240 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1241 1242 // C++ 7.3.1.2p2: 1243 // Members (including explicit specializations of templates) of a named 1244 // namespace can also be defined outside that namespace by explicit 1245 // qualification of the name being defined, provided that the entity being 1246 // defined was already declared in the namespace and the definition appears 1247 // after the point of declaration in a namespace that encloses the 1248 // declarations namespace. 1249 // 1250 // Note that we only check the context at this point. We don't yet 1251 // have enough information to make sure that PrevDecl is actually 1252 // the declaration we want to match. For example, given: 1253 // 1254 // class X { 1255 // void f(); 1256 // void f(float); 1257 // }; 1258 // 1259 // void X::f(int) { } // ill-formed 1260 // 1261 // In this case, PrevDecl will point to the overload set 1262 // containing the two f's declared in X, but neither of them 1263 // matches. 1264 if (!CurContext->Encloses(DC)) { 1265 // The qualifying scope doesn't enclose the original declaration. 1266 // Emit diagnostic based on current scope. 1267 SourceLocation L = D.getIdentifierLoc(); 1268 SourceRange R = D.getCXXScopeSpec().getRange(); 1269 if (isa<FunctionDecl>(CurContext)) { 1270 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1271 } else { 1272 Diag(L, diag::err_invalid_declarator_scope) 1273 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1274 } 1275 InvalidDecl = true; 1276 } 1277 } 1278 1279 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1280 // Maybe we will complain about the shadowed template parameter. 1281 InvalidDecl = InvalidDecl 1282 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1283 // Just pretend that we didn't see the previous declaration. 1284 PrevDecl = 0; 1285 } 1286 1287 // In C++, the previous declaration we find might be a tag type 1288 // (class or enum). In this case, the new declaration will hide the 1289 // tag type. 1290 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1291 PrevDecl = 0; 1292 1293 QualType R = GetTypeForDeclarator(D, S); 1294 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1295 1296 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1297 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1298 InvalidDecl); 1299 } else if (R.getTypePtr()->isFunctionType()) { 1300 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1301 IsFunctionDefinition, InvalidDecl); 1302 } else { 1303 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1304 InvalidDecl); 1305 } 1306 1307 if (New == 0) 1308 return 0; 1309 1310 // Set the lexical context. If the declarator has a C++ scope specifier, the 1311 // lexical context will be different from the semantic context. 1312 New->setLexicalDeclContext(CurContext); 1313 1314 // If this has an identifier, add it to the scope stack. 1315 if (Name) 1316 PushOnScopeChains(New, S); 1317 // If any semantic error occurred, mark the decl as invalid. 1318 if (D.getInvalidType() || InvalidDecl) 1319 New->setInvalidDecl(); 1320 1321 return New; 1322} 1323 1324ScopedDecl* 1325Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1326 QualType R, ScopedDecl* LastDeclarator, 1327 Decl* PrevDecl, bool& InvalidDecl) { 1328 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1329 if (D.getCXXScopeSpec().isSet()) { 1330 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1331 << D.getCXXScopeSpec().getRange(); 1332 InvalidDecl = true; 1333 // Pretend we didn't see the scope specifier. 1334 DC = 0; 1335 } 1336 1337 // Check that there are no default arguments (C++ only). 1338 if (getLangOptions().CPlusPlus) 1339 CheckExtraCXXDefaultArguments(D); 1340 1341 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1342 if (!NewTD) return 0; 1343 1344 // Handle attributes prior to checking for duplicates in MergeVarDecl 1345 ProcessDeclAttributes(NewTD, D); 1346 // Merge the decl with the existing one if appropriate. If the decl is 1347 // in an outer scope, it isn't the same thing. 1348 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1349 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1350 if (NewTD == 0) return 0; 1351 } 1352 1353 if (S->getFnParent() == 0) { 1354 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1355 // then it shall have block scope. 1356 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1357 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1358 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1359 else 1360 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1361 1362 InvalidDecl = true; 1363 } 1364 } 1365 return NewTD; 1366} 1367 1368ScopedDecl* 1369Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1370 QualType R, ScopedDecl* LastDeclarator, 1371 Decl* PrevDecl, bool& InvalidDecl) { 1372 DeclarationName Name = GetNameForDeclarator(D); 1373 1374 // Check that there are no default arguments (C++ only). 1375 if (getLangOptions().CPlusPlus) 1376 CheckExtraCXXDefaultArguments(D); 1377 1378 if (R.getTypePtr()->isObjCInterfaceType()) { 1379 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1380 << D.getIdentifier(); 1381 InvalidDecl = true; 1382 } 1383 1384 VarDecl *NewVD; 1385 VarDecl::StorageClass SC; 1386 switch (D.getDeclSpec().getStorageClassSpec()) { 1387 default: assert(0 && "Unknown storage class!"); 1388 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1389 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1390 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1391 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1392 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1393 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1394 case DeclSpec::SCS_mutable: 1395 // mutable can only appear on non-static class members, so it's always 1396 // an error here 1397 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1398 InvalidDecl = true; 1399 SC = VarDecl::None; 1400 break; 1401 } 1402 1403 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1404 if (!II) { 1405 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1406 << Name.getAsString(); 1407 return 0; 1408 } 1409 1410 if (DC->isRecord()) { 1411 // This is a static data member for a C++ class. 1412 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1413 D.getIdentifierLoc(), II, 1414 R, LastDeclarator); 1415 } else { 1416 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1417 if (S->getFnParent() == 0) { 1418 // C99 6.9p2: The storage-class specifiers auto and register shall not 1419 // appear in the declaration specifiers in an external declaration. 1420 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1421 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1422 InvalidDecl = true; 1423 } 1424 } 1425 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1426 II, R, SC, LastDeclarator, 1427 // FIXME: Move to DeclGroup... 1428 D.getDeclSpec().getSourceRange().getBegin()); 1429 NewVD->setThreadSpecified(ThreadSpecified); 1430 } 1431 // Handle attributes prior to checking for duplicates in MergeVarDecl 1432 ProcessDeclAttributes(NewVD, D); 1433 1434 // Handle GNU asm-label extension (encoded as an attribute). 1435 if (Expr *E = (Expr*) D.getAsmLabel()) { 1436 // The parser guarantees this is a string. 1437 StringLiteral *SE = cast<StringLiteral>(E); 1438 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1439 SE->getByteLength()))); 1440 } 1441 1442 // Emit an error if an address space was applied to decl with local storage. 1443 // This includes arrays of objects with address space qualifiers, but not 1444 // automatic variables that point to other address spaces. 1445 // ISO/IEC TR 18037 S5.1.2 1446 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1447 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1448 InvalidDecl = true; 1449 } 1450 // Merge the decl with the existing one if appropriate. If the decl is 1451 // in an outer scope, it isn't the same thing. 1452 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1453 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1454 // The user tried to define a non-static data member 1455 // out-of-line (C++ [dcl.meaning]p1). 1456 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1457 << D.getCXXScopeSpec().getRange(); 1458 NewVD->Destroy(Context); 1459 return 0; 1460 } 1461 1462 NewVD = MergeVarDecl(NewVD, PrevDecl); 1463 if (NewVD == 0) return 0; 1464 1465 if (D.getCXXScopeSpec().isSet()) { 1466 // No previous declaration in the qualifying scope. 1467 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1468 << Name << D.getCXXScopeSpec().getRange(); 1469 InvalidDecl = true; 1470 } 1471 } 1472 return NewVD; 1473} 1474 1475ScopedDecl* 1476Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1477 QualType R, ScopedDecl *LastDeclarator, 1478 Decl* PrevDecl, bool IsFunctionDefinition, 1479 bool& InvalidDecl) { 1480 assert(R.getTypePtr()->isFunctionType()); 1481 1482 DeclarationName Name = GetNameForDeclarator(D); 1483 FunctionDecl::StorageClass SC = FunctionDecl::None; 1484 switch (D.getDeclSpec().getStorageClassSpec()) { 1485 default: assert(0 && "Unknown storage class!"); 1486 case DeclSpec::SCS_auto: 1487 case DeclSpec::SCS_register: 1488 case DeclSpec::SCS_mutable: 1489 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1490 InvalidDecl = true; 1491 break; 1492 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1493 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1494 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1495 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1496 } 1497 1498 bool isInline = D.getDeclSpec().isInlineSpecified(); 1499 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1500 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1501 1502 FunctionDecl *NewFD; 1503 if (D.getKind() == Declarator::DK_Constructor) { 1504 // This is a C++ constructor declaration. 1505 assert(DC->isRecord() && 1506 "Constructors can only be declared in a member context"); 1507 1508 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1509 1510 // Create the new declaration 1511 NewFD = CXXConstructorDecl::Create(Context, 1512 cast<CXXRecordDecl>(DC), 1513 D.getIdentifierLoc(), Name, R, 1514 isExplicit, isInline, 1515 /*isImplicitlyDeclared=*/false); 1516 1517 if (InvalidDecl) 1518 NewFD->setInvalidDecl(); 1519 } else if (D.getKind() == Declarator::DK_Destructor) { 1520 // This is a C++ destructor declaration. 1521 if (DC->isRecord()) { 1522 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1523 1524 NewFD = CXXDestructorDecl::Create(Context, 1525 cast<CXXRecordDecl>(DC), 1526 D.getIdentifierLoc(), Name, R, 1527 isInline, 1528 /*isImplicitlyDeclared=*/false); 1529 1530 if (InvalidDecl) 1531 NewFD->setInvalidDecl(); 1532 } else { 1533 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1534 1535 // Create a FunctionDecl to satisfy the function definition parsing 1536 // code path. 1537 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1538 Name, R, SC, isInline, LastDeclarator, 1539 // FIXME: Move to DeclGroup... 1540 D.getDeclSpec().getSourceRange().getBegin()); 1541 InvalidDecl = true; 1542 NewFD->setInvalidDecl(); 1543 } 1544 } else if (D.getKind() == Declarator::DK_Conversion) { 1545 if (!DC->isRecord()) { 1546 Diag(D.getIdentifierLoc(), 1547 diag::err_conv_function_not_member); 1548 return 0; 1549 } else { 1550 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1551 1552 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1553 D.getIdentifierLoc(), Name, R, 1554 isInline, isExplicit); 1555 1556 if (InvalidDecl) 1557 NewFD->setInvalidDecl(); 1558 } 1559 } else if (DC->isRecord()) { 1560 // This is a C++ method declaration. 1561 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1562 D.getIdentifierLoc(), Name, R, 1563 (SC == FunctionDecl::Static), isInline, 1564 LastDeclarator); 1565 } else { 1566 NewFD = FunctionDecl::Create(Context, DC, 1567 D.getIdentifierLoc(), 1568 Name, R, SC, isInline, LastDeclarator, 1569 // FIXME: Move to DeclGroup... 1570 D.getDeclSpec().getSourceRange().getBegin()); 1571 } 1572 1573 // Set the lexical context. If the declarator has a C++ 1574 // scope specifier, the lexical context will be different 1575 // from the semantic context. 1576 NewFD->setLexicalDeclContext(CurContext); 1577 1578 // Handle GNU asm-label extension (encoded as an attribute). 1579 if (Expr *E = (Expr*) D.getAsmLabel()) { 1580 // The parser guarantees this is a string. 1581 StringLiteral *SE = cast<StringLiteral>(E); 1582 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1583 SE->getByteLength()))); 1584 } 1585 1586 // Copy the parameter declarations from the declarator D to 1587 // the function declaration NewFD, if they are available. 1588 if (D.getNumTypeObjects() > 0) { 1589 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1590 1591 // Create Decl objects for each parameter, adding them to the 1592 // FunctionDecl. 1593 llvm::SmallVector<ParmVarDecl*, 16> Params; 1594 1595 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1596 // function that takes no arguments, not a function that takes a 1597 // single void argument. 1598 // We let through "const void" here because Sema::GetTypeForDeclarator 1599 // already checks for that case. 1600 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1601 FTI.ArgInfo[0].Param && 1602 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1603 // empty arg list, don't push any params. 1604 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1605 1606 // In C++, the empty parameter-type-list must be spelled "void"; a 1607 // typedef of void is not permitted. 1608 if (getLangOptions().CPlusPlus && 1609 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1610 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1611 } 1612 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1613 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1614 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1615 } 1616 1617 NewFD->setParams(Context, &Params[0], Params.size()); 1618 } else if (R->getAsTypedefType()) { 1619 // When we're declaring a function with a typedef, as in the 1620 // following example, we'll need to synthesize (unnamed) 1621 // parameters for use in the declaration. 1622 // 1623 // @code 1624 // typedef void fn(int); 1625 // fn f; 1626 // @endcode 1627 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1628 if (!FT) { 1629 // This is a typedef of a function with no prototype, so we 1630 // don't need to do anything. 1631 } else if ((FT->getNumArgs() == 0) || 1632 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1633 FT->getArgType(0)->isVoidType())) { 1634 // This is a zero-argument function. We don't need to do anything. 1635 } else { 1636 // Synthesize a parameter for each argument type. 1637 llvm::SmallVector<ParmVarDecl*, 16> Params; 1638 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1639 ArgType != FT->arg_type_end(); ++ArgType) { 1640 Params.push_back(ParmVarDecl::Create(Context, DC, 1641 SourceLocation(), 0, 1642 *ArgType, VarDecl::None, 1643 0, 0)); 1644 } 1645 1646 NewFD->setParams(Context, &Params[0], Params.size()); 1647 } 1648 } 1649 1650 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1651 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1652 else if (isa<CXXDestructorDecl>(NewFD)) { 1653 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1654 Record->setUserDeclaredDestructor(true); 1655 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1656 // user-defined destructor. 1657 Record->setPOD(false); 1658 } else if (CXXConversionDecl *Conversion = 1659 dyn_cast<CXXConversionDecl>(NewFD)) 1660 ActOnConversionDeclarator(Conversion); 1661 1662 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1663 if (NewFD->isOverloadedOperator() && 1664 CheckOverloadedOperatorDeclaration(NewFD)) 1665 NewFD->setInvalidDecl(); 1666 1667 // Merge the decl with the existing one if appropriate. Since C functions 1668 // are in a flat namespace, make sure we consider decls in outer scopes. 1669 if (PrevDecl && 1670 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1671 bool Redeclaration = false; 1672 1673 // If C++, determine whether NewFD is an overload of PrevDecl or 1674 // a declaration that requires merging. If it's an overload, 1675 // there's no more work to do here; we'll just add the new 1676 // function to the scope. 1677 OverloadedFunctionDecl::function_iterator MatchedDecl; 1678 if (!getLangOptions().CPlusPlus || 1679 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1680 Decl *OldDecl = PrevDecl; 1681 1682 // If PrevDecl was an overloaded function, extract the 1683 // FunctionDecl that matched. 1684 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1685 OldDecl = *MatchedDecl; 1686 1687 // NewFD and PrevDecl represent declarations that need to be 1688 // merged. 1689 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1690 1691 if (NewFD == 0) return 0; 1692 if (Redeclaration) { 1693 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1694 1695 // An out-of-line member function declaration must also be a 1696 // definition (C++ [dcl.meaning]p1). 1697 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1698 !InvalidDecl) { 1699 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1700 << D.getCXXScopeSpec().getRange(); 1701 NewFD->setInvalidDecl(); 1702 } 1703 } 1704 } 1705 1706 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1707 // The user tried to provide an out-of-line definition for a 1708 // member function, but there was no such member function 1709 // declared (C++ [class.mfct]p2). For example: 1710 // 1711 // class X { 1712 // void f() const; 1713 // }; 1714 // 1715 // void X::f() { } // ill-formed 1716 // 1717 // Complain about this problem, and attempt to suggest close 1718 // matches (e.g., those that differ only in cv-qualifiers and 1719 // whether the parameter types are references). 1720 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1721 << cast<CXXRecordDecl>(DC)->getDeclName() 1722 << D.getCXXScopeSpec().getRange(); 1723 InvalidDecl = true; 1724 1725 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1726 if (!PrevDecl) { 1727 // Nothing to suggest. 1728 } else if (OverloadedFunctionDecl *Ovl 1729 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1730 for (OverloadedFunctionDecl::function_iterator 1731 Func = Ovl->function_begin(), 1732 FuncEnd = Ovl->function_end(); 1733 Func != FuncEnd; ++Func) { 1734 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1735 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1736 1737 } 1738 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1739 // Suggest this no matter how mismatched it is; it's the only 1740 // thing we have. 1741 unsigned diag; 1742 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1743 diag = diag::note_member_def_close_match; 1744 else if (Method->getBody()) 1745 diag = diag::note_previous_definition; 1746 else 1747 diag = diag::note_previous_declaration; 1748 Diag(Method->getLocation(), diag); 1749 } 1750 1751 PrevDecl = 0; 1752 } 1753 } 1754 // Handle attributes. We need to have merged decls when handling attributes 1755 // (for example to check for conflicts, etc). 1756 ProcessDeclAttributes(NewFD, D); 1757 1758 if (getLangOptions().CPlusPlus) { 1759 // In C++, check default arguments now that we have merged decls. 1760 CheckCXXDefaultArguments(NewFD); 1761 1762 // An out-of-line member function declaration must also be a 1763 // definition (C++ [dcl.meaning]p1). 1764 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1765 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1766 << D.getCXXScopeSpec().getRange(); 1767 InvalidDecl = true; 1768 } 1769 } 1770 return NewFD; 1771} 1772 1773void Sema::InitializerElementNotConstant(const Expr *Init) { 1774 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1775 << Init->getSourceRange(); 1776} 1777 1778bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1779 switch (Init->getStmtClass()) { 1780 default: 1781 InitializerElementNotConstant(Init); 1782 return true; 1783 case Expr::ParenExprClass: { 1784 const ParenExpr* PE = cast<ParenExpr>(Init); 1785 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1786 } 1787 case Expr::CompoundLiteralExprClass: 1788 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1789 case Expr::DeclRefExprClass: 1790 case Expr::QualifiedDeclRefExprClass: { 1791 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1792 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1793 if (VD->hasGlobalStorage()) 1794 return false; 1795 InitializerElementNotConstant(Init); 1796 return true; 1797 } 1798 if (isa<FunctionDecl>(D)) 1799 return false; 1800 InitializerElementNotConstant(Init); 1801 return true; 1802 } 1803 case Expr::MemberExprClass: { 1804 const MemberExpr *M = cast<MemberExpr>(Init); 1805 if (M->isArrow()) 1806 return CheckAddressConstantExpression(M->getBase()); 1807 return CheckAddressConstantExpressionLValue(M->getBase()); 1808 } 1809 case Expr::ArraySubscriptExprClass: { 1810 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1811 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1812 return CheckAddressConstantExpression(ASE->getBase()) || 1813 CheckArithmeticConstantExpression(ASE->getIdx()); 1814 } 1815 case Expr::StringLiteralClass: 1816 case Expr::PredefinedExprClass: 1817 return false; 1818 case Expr::UnaryOperatorClass: { 1819 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1820 1821 // C99 6.6p9 1822 if (Exp->getOpcode() == UnaryOperator::Deref) 1823 return CheckAddressConstantExpression(Exp->getSubExpr()); 1824 1825 InitializerElementNotConstant(Init); 1826 return true; 1827 } 1828 } 1829} 1830 1831bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1832 switch (Init->getStmtClass()) { 1833 default: 1834 InitializerElementNotConstant(Init); 1835 return true; 1836 case Expr::ParenExprClass: 1837 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1838 case Expr::StringLiteralClass: 1839 case Expr::ObjCStringLiteralClass: 1840 return false; 1841 case Expr::CallExprClass: 1842 case Expr::CXXOperatorCallExprClass: 1843 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1844 if (cast<CallExpr>(Init)->isBuiltinCall() == 1845 Builtin::BI__builtin___CFStringMakeConstantString) 1846 return false; 1847 1848 InitializerElementNotConstant(Init); 1849 return true; 1850 1851 case Expr::UnaryOperatorClass: { 1852 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1853 1854 // C99 6.6p9 1855 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1856 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1857 1858 if (Exp->getOpcode() == UnaryOperator::Extension) 1859 return CheckAddressConstantExpression(Exp->getSubExpr()); 1860 1861 InitializerElementNotConstant(Init); 1862 return true; 1863 } 1864 case Expr::BinaryOperatorClass: { 1865 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1866 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1867 1868 Expr *PExp = Exp->getLHS(); 1869 Expr *IExp = Exp->getRHS(); 1870 if (IExp->getType()->isPointerType()) 1871 std::swap(PExp, IExp); 1872 1873 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1874 return CheckAddressConstantExpression(PExp) || 1875 CheckArithmeticConstantExpression(IExp); 1876 } 1877 case Expr::ImplicitCastExprClass: 1878 case Expr::CStyleCastExprClass: { 1879 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1880 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1881 // Check for implicit promotion 1882 if (SubExpr->getType()->isFunctionType() || 1883 SubExpr->getType()->isArrayType()) 1884 return CheckAddressConstantExpressionLValue(SubExpr); 1885 } 1886 1887 // Check for pointer->pointer cast 1888 if (SubExpr->getType()->isPointerType()) 1889 return CheckAddressConstantExpression(SubExpr); 1890 1891 if (SubExpr->getType()->isIntegralType()) { 1892 // Check for the special-case of a pointer->int->pointer cast; 1893 // this isn't standard, but some code requires it. See 1894 // PR2720 for an example. 1895 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1896 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1897 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1898 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1899 if (IntWidth >= PointerWidth) { 1900 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1901 } 1902 } 1903 } 1904 } 1905 if (SubExpr->getType()->isArithmeticType()) { 1906 return CheckArithmeticConstantExpression(SubExpr); 1907 } 1908 1909 InitializerElementNotConstant(Init); 1910 return true; 1911 } 1912 case Expr::ConditionalOperatorClass: { 1913 // FIXME: Should we pedwarn here? 1914 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1915 if (!Exp->getCond()->getType()->isArithmeticType()) { 1916 InitializerElementNotConstant(Init); 1917 return true; 1918 } 1919 if (CheckArithmeticConstantExpression(Exp->getCond())) 1920 return true; 1921 if (Exp->getLHS() && 1922 CheckAddressConstantExpression(Exp->getLHS())) 1923 return true; 1924 return CheckAddressConstantExpression(Exp->getRHS()); 1925 } 1926 case Expr::AddrLabelExprClass: 1927 return false; 1928 } 1929} 1930 1931static const Expr* FindExpressionBaseAddress(const Expr* E); 1932 1933static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1934 switch (E->getStmtClass()) { 1935 default: 1936 return E; 1937 case Expr::ParenExprClass: { 1938 const ParenExpr* PE = cast<ParenExpr>(E); 1939 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1940 } 1941 case Expr::MemberExprClass: { 1942 const MemberExpr *M = cast<MemberExpr>(E); 1943 if (M->isArrow()) 1944 return FindExpressionBaseAddress(M->getBase()); 1945 return FindExpressionBaseAddressLValue(M->getBase()); 1946 } 1947 case Expr::ArraySubscriptExprClass: { 1948 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1949 return FindExpressionBaseAddress(ASE->getBase()); 1950 } 1951 case Expr::UnaryOperatorClass: { 1952 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1953 1954 if (Exp->getOpcode() == UnaryOperator::Deref) 1955 return FindExpressionBaseAddress(Exp->getSubExpr()); 1956 1957 return E; 1958 } 1959 } 1960} 1961 1962static const Expr* FindExpressionBaseAddress(const Expr* E) { 1963 switch (E->getStmtClass()) { 1964 default: 1965 return E; 1966 case Expr::ParenExprClass: { 1967 const ParenExpr* PE = cast<ParenExpr>(E); 1968 return FindExpressionBaseAddress(PE->getSubExpr()); 1969 } 1970 case Expr::UnaryOperatorClass: { 1971 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1972 1973 // C99 6.6p9 1974 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1975 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1976 1977 if (Exp->getOpcode() == UnaryOperator::Extension) 1978 return FindExpressionBaseAddress(Exp->getSubExpr()); 1979 1980 return E; 1981 } 1982 case Expr::BinaryOperatorClass: { 1983 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1984 1985 Expr *PExp = Exp->getLHS(); 1986 Expr *IExp = Exp->getRHS(); 1987 if (IExp->getType()->isPointerType()) 1988 std::swap(PExp, IExp); 1989 1990 return FindExpressionBaseAddress(PExp); 1991 } 1992 case Expr::ImplicitCastExprClass: { 1993 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1994 1995 // Check for implicit promotion 1996 if (SubExpr->getType()->isFunctionType() || 1997 SubExpr->getType()->isArrayType()) 1998 return FindExpressionBaseAddressLValue(SubExpr); 1999 2000 // Check for pointer->pointer cast 2001 if (SubExpr->getType()->isPointerType()) 2002 return FindExpressionBaseAddress(SubExpr); 2003 2004 // We assume that we have an arithmetic expression here; 2005 // if we don't, we'll figure it out later 2006 return 0; 2007 } 2008 case Expr::CStyleCastExprClass: { 2009 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2010 2011 // Check for pointer->pointer cast 2012 if (SubExpr->getType()->isPointerType()) 2013 return FindExpressionBaseAddress(SubExpr); 2014 2015 // We assume that we have an arithmetic expression here; 2016 // if we don't, we'll figure it out later 2017 return 0; 2018 } 2019 } 2020} 2021 2022bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2023 switch (Init->getStmtClass()) { 2024 default: 2025 InitializerElementNotConstant(Init); 2026 return true; 2027 case Expr::ParenExprClass: { 2028 const ParenExpr* PE = cast<ParenExpr>(Init); 2029 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2030 } 2031 case Expr::FloatingLiteralClass: 2032 case Expr::IntegerLiteralClass: 2033 case Expr::CharacterLiteralClass: 2034 case Expr::ImaginaryLiteralClass: 2035 case Expr::TypesCompatibleExprClass: 2036 case Expr::CXXBoolLiteralExprClass: 2037 return false; 2038 case Expr::CallExprClass: 2039 case Expr::CXXOperatorCallExprClass: { 2040 const CallExpr *CE = cast<CallExpr>(Init); 2041 2042 // Allow any constant foldable calls to builtins. 2043 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2044 return false; 2045 2046 InitializerElementNotConstant(Init); 2047 return true; 2048 } 2049 case Expr::DeclRefExprClass: 2050 case Expr::QualifiedDeclRefExprClass: { 2051 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2052 if (isa<EnumConstantDecl>(D)) 2053 return false; 2054 InitializerElementNotConstant(Init); 2055 return true; 2056 } 2057 case Expr::CompoundLiteralExprClass: 2058 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2059 // but vectors are allowed to be magic. 2060 if (Init->getType()->isVectorType()) 2061 return false; 2062 InitializerElementNotConstant(Init); 2063 return true; 2064 case Expr::UnaryOperatorClass: { 2065 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2066 2067 switch (Exp->getOpcode()) { 2068 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2069 // See C99 6.6p3. 2070 default: 2071 InitializerElementNotConstant(Init); 2072 return true; 2073 case UnaryOperator::OffsetOf: 2074 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2075 return false; 2076 InitializerElementNotConstant(Init); 2077 return true; 2078 case UnaryOperator::Extension: 2079 case UnaryOperator::LNot: 2080 case UnaryOperator::Plus: 2081 case UnaryOperator::Minus: 2082 case UnaryOperator::Not: 2083 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2084 } 2085 } 2086 case Expr::SizeOfAlignOfExprClass: { 2087 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2088 // Special check for void types, which are allowed as an extension 2089 if (Exp->getTypeOfArgument()->isVoidType()) 2090 return false; 2091 // alignof always evaluates to a constant. 2092 // FIXME: is sizeof(int[3.0]) a constant expression? 2093 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2094 InitializerElementNotConstant(Init); 2095 return true; 2096 } 2097 return false; 2098 } 2099 case Expr::BinaryOperatorClass: { 2100 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2101 2102 if (Exp->getLHS()->getType()->isArithmeticType() && 2103 Exp->getRHS()->getType()->isArithmeticType()) { 2104 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2105 CheckArithmeticConstantExpression(Exp->getRHS()); 2106 } 2107 2108 if (Exp->getLHS()->getType()->isPointerType() && 2109 Exp->getRHS()->getType()->isPointerType()) { 2110 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2111 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2112 2113 // Only allow a null (constant integer) base; we could 2114 // allow some additional cases if necessary, but this 2115 // is sufficient to cover offsetof-like constructs. 2116 if (!LHSBase && !RHSBase) { 2117 return CheckAddressConstantExpression(Exp->getLHS()) || 2118 CheckAddressConstantExpression(Exp->getRHS()); 2119 } 2120 } 2121 2122 InitializerElementNotConstant(Init); 2123 return true; 2124 } 2125 case Expr::ImplicitCastExprClass: 2126 case Expr::CStyleCastExprClass: { 2127 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2128 if (SubExpr->getType()->isArithmeticType()) 2129 return CheckArithmeticConstantExpression(SubExpr); 2130 2131 if (SubExpr->getType()->isPointerType()) { 2132 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2133 // If the pointer has a null base, this is an offsetof-like construct 2134 if (!Base) 2135 return CheckAddressConstantExpression(SubExpr); 2136 } 2137 2138 InitializerElementNotConstant(Init); 2139 return true; 2140 } 2141 case Expr::ConditionalOperatorClass: { 2142 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2143 2144 // If GNU extensions are disabled, we require all operands to be arithmetic 2145 // constant expressions. 2146 if (getLangOptions().NoExtensions) { 2147 return CheckArithmeticConstantExpression(Exp->getCond()) || 2148 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2149 CheckArithmeticConstantExpression(Exp->getRHS()); 2150 } 2151 2152 // Otherwise, we have to emulate some of the behavior of fold here. 2153 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2154 // because it can constant fold things away. To retain compatibility with 2155 // GCC code, we see if we can fold the condition to a constant (which we 2156 // should always be able to do in theory). If so, we only require the 2157 // specified arm of the conditional to be a constant. This is a horrible 2158 // hack, but is require by real world code that uses __builtin_constant_p. 2159 Expr::EvalResult EvalResult; 2160 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2161 EvalResult.HasSideEffects) { 2162 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2163 // won't be able to either. Use it to emit the diagnostic though. 2164 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2165 assert(Res && "Evaluate couldn't evaluate this constant?"); 2166 return Res; 2167 } 2168 2169 // Verify that the side following the condition is also a constant. 2170 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2171 if (EvalResult.Val.getInt() == 0) 2172 std::swap(TrueSide, FalseSide); 2173 2174 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2175 return true; 2176 2177 // Okay, the evaluated side evaluates to a constant, so we accept this. 2178 // Check to see if the other side is obviously not a constant. If so, 2179 // emit a warning that this is a GNU extension. 2180 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2181 Diag(Init->getExprLoc(), 2182 diag::ext_typecheck_expression_not_constant_but_accepted) 2183 << FalseSide->getSourceRange(); 2184 return false; 2185 } 2186 } 2187} 2188 2189bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2190 Expr::EvalResult Result; 2191 2192 Init = Init->IgnoreParens(); 2193 2194 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 2195 return false; 2196 2197 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2198 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2199 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2200 2201 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2202 return CheckForConstantInitializer(e->getInitializer(), DclT); 2203 2204 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2205 unsigned numInits = Exp->getNumInits(); 2206 for (unsigned i = 0; i < numInits; i++) { 2207 // FIXME: Need to get the type of the declaration for C++, 2208 // because it could be a reference? 2209 if (CheckForConstantInitializer(Exp->getInit(i), 2210 Exp->getInit(i)->getType())) 2211 return true; 2212 } 2213 return false; 2214 } 2215 2216 // FIXME: We can probably remove some of this code below, now that 2217 // Expr::Evaluate is doing the heavy lifting for scalars. 2218 2219 if (Init->isNullPointerConstant(Context)) 2220 return false; 2221 if (Init->getType()->isArithmeticType()) { 2222 QualType InitTy = Context.getCanonicalType(Init->getType()) 2223 .getUnqualifiedType(); 2224 if (InitTy == Context.BoolTy) { 2225 // Special handling for pointers implicitly cast to bool; 2226 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2227 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2228 Expr* SubE = ICE->getSubExpr(); 2229 if (SubE->getType()->isPointerType() || 2230 SubE->getType()->isArrayType() || 2231 SubE->getType()->isFunctionType()) { 2232 return CheckAddressConstantExpression(Init); 2233 } 2234 } 2235 } else if (InitTy->isIntegralType()) { 2236 Expr* SubE = 0; 2237 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2238 SubE = CE->getSubExpr(); 2239 // Special check for pointer cast to int; we allow as an extension 2240 // an address constant cast to an integer if the integer 2241 // is of an appropriate width (this sort of code is apparently used 2242 // in some places). 2243 // FIXME: Add pedwarn? 2244 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2245 if (SubE && (SubE->getType()->isPointerType() || 2246 SubE->getType()->isArrayType() || 2247 SubE->getType()->isFunctionType())) { 2248 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2249 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2250 if (IntWidth >= PointerWidth) 2251 return CheckAddressConstantExpression(Init); 2252 } 2253 } 2254 2255 return CheckArithmeticConstantExpression(Init); 2256 } 2257 2258 if (Init->getType()->isPointerType()) 2259 return CheckAddressConstantExpression(Init); 2260 2261 // An array type at the top level that isn't an init-list must 2262 // be a string literal 2263 if (Init->getType()->isArrayType()) 2264 return false; 2265 2266 if (Init->getType()->isFunctionType()) 2267 return false; 2268 2269 // Allow block exprs at top level. 2270 if (Init->getType()->isBlockPointerType()) 2271 return false; 2272 2273 // GCC cast to union extension 2274 // note: the validity of the cast expr is checked by CheckCastTypes() 2275 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2276 QualType T = C->getType(); 2277 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2278 } 2279 2280 InitializerElementNotConstant(Init); 2281 return true; 2282} 2283 2284void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2285 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2286} 2287 2288/// AddInitializerToDecl - Adds the initializer Init to the 2289/// declaration dcl. If DirectInit is true, this is C++ direct 2290/// initialization rather than copy initialization. 2291void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2292 Decl *RealDecl = static_cast<Decl *>(dcl); 2293 Expr *Init = static_cast<Expr *>(init.release()); 2294 assert(Init && "missing initializer"); 2295 2296 // If there is no declaration, there was an error parsing it. Just ignore 2297 // the initializer. 2298 if (RealDecl == 0) { 2299 delete Init; 2300 return; 2301 } 2302 2303 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2304 if (!VDecl) { 2305 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2306 diag::err_illegal_initializer); 2307 RealDecl->setInvalidDecl(); 2308 return; 2309 } 2310 // Get the decls type and save a reference for later, since 2311 // CheckInitializerTypes may change it. 2312 QualType DclT = VDecl->getType(), SavT = DclT; 2313 if (VDecl->isBlockVarDecl()) { 2314 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2315 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2316 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2317 VDecl->setInvalidDecl(); 2318 } else if (!VDecl->isInvalidDecl()) { 2319 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2320 VDecl->getDeclName(), DirectInit)) 2321 VDecl->setInvalidDecl(); 2322 2323 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2324 if (!getLangOptions().CPlusPlus) { 2325 if (SC == VarDecl::Static) // C99 6.7.8p4. 2326 CheckForConstantInitializer(Init, DclT); 2327 } 2328 } 2329 } else if (VDecl->isFileVarDecl()) { 2330 if (VDecl->getStorageClass() == VarDecl::Extern) 2331 Diag(VDecl->getLocation(), diag::warn_extern_init); 2332 if (!VDecl->isInvalidDecl()) 2333 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2334 VDecl->getDeclName(), DirectInit)) 2335 VDecl->setInvalidDecl(); 2336 2337 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2338 if (!getLangOptions().CPlusPlus) { 2339 // C99 6.7.8p4. All file scoped initializers need to be constant. 2340 CheckForConstantInitializer(Init, DclT); 2341 } 2342 } 2343 // If the type changed, it means we had an incomplete type that was 2344 // completed by the initializer. For example: 2345 // int ary[] = { 1, 3, 5 }; 2346 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2347 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2348 VDecl->setType(DclT); 2349 Init->setType(DclT); 2350 } 2351 2352 // Attach the initializer to the decl. 2353 VDecl->setInit(Init); 2354 return; 2355} 2356 2357void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2358 Decl *RealDecl = static_cast<Decl *>(dcl); 2359 2360 // If there is no declaration, there was an error parsing it. Just ignore it. 2361 if (RealDecl == 0) 2362 return; 2363 2364 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2365 QualType Type = Var->getType(); 2366 // C++ [dcl.init.ref]p3: 2367 // The initializer can be omitted for a reference only in a 2368 // parameter declaration (8.3.5), in the declaration of a 2369 // function return type, in the declaration of a class member 2370 // within its class declaration (9.2), and where the extern 2371 // specifier is explicitly used. 2372 if (Type->isReferenceType() && 2373 Var->getStorageClass() != VarDecl::Extern && 2374 Var->getStorageClass() != VarDecl::PrivateExtern) { 2375 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2376 << Var->getDeclName() 2377 << SourceRange(Var->getLocation(), Var->getLocation()); 2378 Var->setInvalidDecl(); 2379 return; 2380 } 2381 2382 // C++ [dcl.init]p9: 2383 // 2384 // If no initializer is specified for an object, and the object 2385 // is of (possibly cv-qualified) non-POD class type (or array 2386 // thereof), the object shall be default-initialized; if the 2387 // object is of const-qualified type, the underlying class type 2388 // shall have a user-declared default constructor. 2389 if (getLangOptions().CPlusPlus) { 2390 QualType InitType = Type; 2391 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2392 InitType = Array->getElementType(); 2393 if (Var->getStorageClass() != VarDecl::Extern && 2394 Var->getStorageClass() != VarDecl::PrivateExtern && 2395 InitType->isRecordType()) { 2396 const CXXConstructorDecl *Constructor 2397 = PerformInitializationByConstructor(InitType, 0, 0, 2398 Var->getLocation(), 2399 SourceRange(Var->getLocation(), 2400 Var->getLocation()), 2401 Var->getDeclName(), 2402 IK_Default); 2403 if (!Constructor) 2404 Var->setInvalidDecl(); 2405 } 2406 } 2407 2408#if 0 2409 // FIXME: Temporarily disabled because we are not properly parsing 2410 // linkage specifications on declarations, e.g., 2411 // 2412 // extern "C" const CGPoint CGPointerZero; 2413 // 2414 // C++ [dcl.init]p9: 2415 // 2416 // If no initializer is specified for an object, and the 2417 // object is of (possibly cv-qualified) non-POD class type (or 2418 // array thereof), the object shall be default-initialized; if 2419 // the object is of const-qualified type, the underlying class 2420 // type shall have a user-declared default 2421 // constructor. Otherwise, if no initializer is specified for 2422 // an object, the object and its subobjects, if any, have an 2423 // indeterminate initial value; if the object or any of its 2424 // subobjects are of const-qualified type, the program is 2425 // ill-formed. 2426 // 2427 // This isn't technically an error in C, so we don't diagnose it. 2428 // 2429 // FIXME: Actually perform the POD/user-defined default 2430 // constructor check. 2431 if (getLangOptions().CPlusPlus && 2432 Context.getCanonicalType(Type).isConstQualified() && 2433 Var->getStorageClass() != VarDecl::Extern) 2434 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2435 << Var->getName() 2436 << SourceRange(Var->getLocation(), Var->getLocation()); 2437#endif 2438 } 2439} 2440 2441/// The declarators are chained together backwards, reverse the list. 2442Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2443 // Often we have single declarators, handle them quickly. 2444 Decl *GroupDecl = static_cast<Decl*>(group); 2445 if (GroupDecl == 0) 2446 return 0; 2447 2448 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2449 ScopedDecl *NewGroup = 0; 2450 if (Group->getNextDeclarator() == 0) 2451 NewGroup = Group; 2452 else { // reverse the list. 2453 while (Group) { 2454 ScopedDecl *Next = Group->getNextDeclarator(); 2455 Group->setNextDeclarator(NewGroup); 2456 NewGroup = Group; 2457 Group = Next; 2458 } 2459 } 2460 // Perform semantic analysis that depends on having fully processed both 2461 // the declarator and initializer. 2462 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2463 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2464 if (!IDecl) 2465 continue; 2466 QualType T = IDecl->getType(); 2467 2468 if (T->isVariableArrayType()) { 2469 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2470 2471 // FIXME: This won't give the correct result for 2472 // int a[10][n]; 2473 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2474 if (IDecl->isFileVarDecl()) { 2475 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2476 SizeRange; 2477 2478 IDecl->setInvalidDecl(); 2479 } else { 2480 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2481 // static storage duration, it shall not have a variable length array. 2482 if (IDecl->getStorageClass() == VarDecl::Static) { 2483 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2484 << SizeRange; 2485 IDecl->setInvalidDecl(); 2486 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2487 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2488 << SizeRange; 2489 IDecl->setInvalidDecl(); 2490 } 2491 } 2492 } else if (T->isVariablyModifiedType()) { 2493 if (IDecl->isFileVarDecl()) { 2494 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2495 IDecl->setInvalidDecl(); 2496 } else { 2497 if (IDecl->getStorageClass() == VarDecl::Extern) { 2498 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2499 IDecl->setInvalidDecl(); 2500 } 2501 } 2502 } 2503 2504 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2505 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2506 if (IDecl->isBlockVarDecl() && 2507 IDecl->getStorageClass() != VarDecl::Extern) { 2508 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2509 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2510 IDecl->setInvalidDecl(); 2511 } 2512 } 2513 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2514 // object that has file scope without an initializer, and without a 2515 // storage-class specifier or with the storage-class specifier "static", 2516 // constitutes a tentative definition. Note: A tentative definition with 2517 // external linkage is valid (C99 6.2.2p5). 2518 if (isTentativeDefinition(IDecl)) { 2519 if (T->isIncompleteArrayType()) { 2520 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2521 // array to be completed. Don't issue a diagnostic. 2522 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2523 // C99 6.9.2p3: If the declaration of an identifier for an object is 2524 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2525 // declared type shall not be an incomplete type. 2526 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2527 IDecl->setInvalidDecl(); 2528 } 2529 } 2530 if (IDecl->isFileVarDecl()) 2531 CheckForFileScopedRedefinitions(S, IDecl); 2532 } 2533 return NewGroup; 2534} 2535 2536/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2537/// to introduce parameters into function prototype scope. 2538Sema::DeclTy * 2539Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2540 const DeclSpec &DS = D.getDeclSpec(); 2541 2542 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2543 VarDecl::StorageClass StorageClass = VarDecl::None; 2544 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2545 StorageClass = VarDecl::Register; 2546 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2547 Diag(DS.getStorageClassSpecLoc(), 2548 diag::err_invalid_storage_class_in_func_decl); 2549 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2550 } 2551 if (DS.isThreadSpecified()) { 2552 Diag(DS.getThreadSpecLoc(), 2553 diag::err_invalid_storage_class_in_func_decl); 2554 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2555 } 2556 2557 // Check that there are no default arguments inside the type of this 2558 // parameter (C++ only). 2559 if (getLangOptions().CPlusPlus) 2560 CheckExtraCXXDefaultArguments(D); 2561 2562 // In this context, we *do not* check D.getInvalidType(). If the declarator 2563 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2564 // though it will not reflect the user specified type. 2565 QualType parmDeclType = GetTypeForDeclarator(D, S); 2566 2567 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2568 2569 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2570 // Can this happen for params? We already checked that they don't conflict 2571 // among each other. Here they can only shadow globals, which is ok. 2572 IdentifierInfo *II = D.getIdentifier(); 2573 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2574 if (PrevDecl->isTemplateParameter()) { 2575 // Maybe we will complain about the shadowed template parameter. 2576 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2577 // Just pretend that we didn't see the previous declaration. 2578 PrevDecl = 0; 2579 } else if (S->isDeclScope(PrevDecl)) { 2580 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2581 2582 // Recover by removing the name 2583 II = 0; 2584 D.SetIdentifier(0, D.getIdentifierLoc()); 2585 } 2586 } 2587 2588 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2589 // Doing the promotion here has a win and a loss. The win is the type for 2590 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2591 // code generator). The loss is the orginal type isn't preserved. For example: 2592 // 2593 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2594 // int blockvardecl[5]; 2595 // sizeof(parmvardecl); // size == 4 2596 // sizeof(blockvardecl); // size == 20 2597 // } 2598 // 2599 // For expressions, all implicit conversions are captured using the 2600 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2601 // 2602 // FIXME: If a source translation tool needs to see the original type, then 2603 // we need to consider storing both types (in ParmVarDecl)... 2604 // 2605 if (parmDeclType->isArrayType()) { 2606 // int x[restrict 4] -> int *restrict 2607 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2608 } else if (parmDeclType->isFunctionType()) 2609 parmDeclType = Context.getPointerType(parmDeclType); 2610 2611 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2612 D.getIdentifierLoc(), II, 2613 parmDeclType, StorageClass, 2614 0, 0); 2615 2616 if (D.getInvalidType()) 2617 New->setInvalidDecl(); 2618 2619 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2620 if (D.getCXXScopeSpec().isSet()) { 2621 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2622 << D.getCXXScopeSpec().getRange(); 2623 New->setInvalidDecl(); 2624 } 2625 2626 // Add the parameter declaration into this scope. 2627 S->AddDecl(New); 2628 if (II) 2629 IdResolver.AddDecl(New); 2630 2631 ProcessDeclAttributes(New, D); 2632 return New; 2633 2634} 2635 2636Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2637 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2638 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2639 "Not a function declarator!"); 2640 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2641 2642 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2643 // for a K&R function. 2644 if (!FTI.hasPrototype) { 2645 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2646 if (FTI.ArgInfo[i].Param == 0) { 2647 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2648 << FTI.ArgInfo[i].Ident; 2649 // Implicitly declare the argument as type 'int' for lack of a better 2650 // type. 2651 DeclSpec DS; 2652 const char* PrevSpec; // unused 2653 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2654 PrevSpec); 2655 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2656 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2657 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2658 } 2659 } 2660 } else { 2661 // FIXME: Diagnose arguments without names in C. 2662 } 2663 2664 Scope *ParentScope = FnBodyScope->getParent(); 2665 2666 return ActOnStartOfFunctionDef(FnBodyScope, 2667 ActOnDeclarator(ParentScope, D, 0, 2668 /*IsFunctionDefinition=*/true)); 2669} 2670 2671Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2672 Decl *decl = static_cast<Decl*>(D); 2673 FunctionDecl *FD = cast<FunctionDecl>(decl); 2674 2675 // See if this is a redefinition. 2676 const FunctionDecl *Definition; 2677 if (FD->getBody(Definition)) { 2678 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2679 Diag(Definition->getLocation(), diag::note_previous_definition); 2680 } 2681 2682 PushDeclContext(FnBodyScope, FD); 2683 2684 // Check the validity of our function parameters 2685 CheckParmsForFunctionDef(FD); 2686 2687 // Introduce our parameters into the function scope 2688 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2689 ParmVarDecl *Param = FD->getParamDecl(p); 2690 Param->setOwningFunction(FD); 2691 2692 // If this has an identifier, add it to the scope stack. 2693 if (Param->getIdentifier()) 2694 PushOnScopeChains(Param, FnBodyScope); 2695 } 2696 2697 // Checking attributes of current function definition 2698 // dllimport attribute. 2699 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2700 // dllimport attribute cannot be applied to definition. 2701 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2702 Diag(FD->getLocation(), 2703 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2704 << "dllimport"; 2705 FD->setInvalidDecl(); 2706 return FD; 2707 } else { 2708 // If a symbol previously declared dllimport is later defined, the 2709 // attribute is ignored in subsequent references, and a warning is 2710 // emitted. 2711 Diag(FD->getLocation(), 2712 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2713 << FD->getNameAsCString() << "dllimport"; 2714 } 2715 } 2716 return FD; 2717} 2718 2719Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2720 Decl *dcl = static_cast<Decl *>(D); 2721 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2722 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2723 FD->setBody(Body); 2724 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2725 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2726 MD->setBody((Stmt*)Body); 2727 } else 2728 return 0; 2729 PopDeclContext(); 2730 // Verify and clean out per-function state. 2731 2732 // Check goto/label use. 2733 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2734 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2735 // Verify that we have no forward references left. If so, there was a goto 2736 // or address of a label taken, but no definition of it. Label fwd 2737 // definitions are indicated with a null substmt. 2738 if (I->second->getSubStmt() == 0) { 2739 LabelStmt *L = I->second; 2740 // Emit error. 2741 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2742 2743 // At this point, we have gotos that use the bogus label. Stitch it into 2744 // the function body so that they aren't leaked and that the AST is well 2745 // formed. 2746 if (Body) { 2747 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2748 cast<CompoundStmt>(Body)->push_back(L); 2749 } else { 2750 // The whole function wasn't parsed correctly, just delete this. 2751 delete L; 2752 } 2753 } 2754 } 2755 LabelMap.clear(); 2756 2757 return D; 2758} 2759 2760/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2761/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2762ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2763 IdentifierInfo &II, Scope *S) { 2764 // Extension in C99. Legal in C90, but warn about it. 2765 if (getLangOptions().C99) 2766 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2767 else 2768 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2769 2770 // FIXME: handle stuff like: 2771 // void foo() { extern float X(); } 2772 // void bar() { X(); } <-- implicit decl for X in another scope. 2773 2774 // Set a Declarator for the implicit definition: int foo(); 2775 const char *Dummy; 2776 DeclSpec DS; 2777 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2778 Error = Error; // Silence warning. 2779 assert(!Error && "Error setting up implicit decl!"); 2780 Declarator D(DS, Declarator::BlockContext); 2781 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2782 D.SetIdentifier(&II, Loc); 2783 2784 // Insert this function into translation-unit scope. 2785 2786 DeclContext *PrevDC = CurContext; 2787 CurContext = Context.getTranslationUnitDecl(); 2788 2789 FunctionDecl *FD = 2790 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2791 FD->setImplicit(); 2792 2793 CurContext = PrevDC; 2794 2795 return FD; 2796} 2797 2798 2799TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2800 ScopedDecl *LastDeclarator) { 2801 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2802 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2803 2804 // Scope manipulation handled by caller. 2805 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2806 D.getIdentifierLoc(), 2807 D.getIdentifier(), 2808 T, LastDeclarator); 2809 if (D.getInvalidType()) 2810 NewTD->setInvalidDecl(); 2811 return NewTD; 2812} 2813 2814/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2815/// former case, Name will be non-null. In the later case, Name will be null. 2816/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2817/// reference/declaration/definition of a tag. 2818Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2819 SourceLocation KWLoc, const CXXScopeSpec &SS, 2820 IdentifierInfo *Name, SourceLocation NameLoc, 2821 AttributeList *Attr, 2822 MultiTemplateParamsArg TemplateParameterLists) { 2823 // If this is not a definition, it must have a name. 2824 assert((Name != 0 || TK == TK_Definition) && 2825 "Nameless record must be a definition!"); 2826 2827 TagDecl::TagKind Kind; 2828 switch (TagSpec) { 2829 default: assert(0 && "Unknown tag type!"); 2830 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2831 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2832 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2833 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2834 } 2835 2836 DeclContext *SearchDC = CurContext; 2837 DeclContext *DC = CurContext; 2838 DeclContext *LexicalContext = CurContext; 2839 ScopedDecl *PrevDecl = 0; 2840 2841 bool Invalid = false; 2842 2843 if (Name && SS.isNotEmpty()) { 2844 // We have a nested-name tag ('struct foo::bar'). 2845 2846 // Check for invalid 'foo::'. 2847 if (SS.isInvalid()) { 2848 Name = 0; 2849 goto CreateNewDecl; 2850 } 2851 2852 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2853 // Look-up name inside 'foo::'. 2854 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC) 2855 .getAsDecl()); 2856 2857 // A tag 'foo::bar' must already exist. 2858 if (PrevDecl == 0) { 2859 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2860 Name = 0; 2861 goto CreateNewDecl; 2862 } 2863 } else { 2864 // If this is a named struct, check to see if there was a previous forward 2865 // declaration or definition. 2866 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2867 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S) 2868 .getAsDecl()); 2869 2870 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2871 // FIXME: This makes sure that we ignore the contexts associated 2872 // with C structs, unions, and enums when looking for a matching 2873 // tag declaration or definition. See the similar lookup tweak 2874 // in Sema::LookupDecl; is there a better way to deal with this? 2875 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2876 SearchDC = SearchDC->getParent(); 2877 } 2878 } 2879 2880 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2881 // Maybe we will complain about the shadowed template parameter. 2882 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2883 // Just pretend that we didn't see the previous declaration. 2884 PrevDecl = 0; 2885 } 2886 2887 if (PrevDecl) { 2888 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2889 "unexpected Decl type"); 2890 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2891 // If this is a use of a previous tag, or if the tag is already declared 2892 // in the same scope (so that the definition/declaration completes or 2893 // rementions the tag), reuse the decl. 2894 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2895 // Make sure that this wasn't declared as an enum and now used as a 2896 // struct or something similar. 2897 if (PrevTagDecl->getTagKind() != Kind) { 2898 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2899 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2900 // Recover by making this an anonymous redefinition. 2901 Name = 0; 2902 PrevDecl = 0; 2903 Invalid = true; 2904 } else { 2905 // If this is a use, just return the declaration we found. 2906 2907 // FIXME: In the future, return a variant or some other clue 2908 // for the consumer of this Decl to know it doesn't own it. 2909 // For our current ASTs this shouldn't be a problem, but will 2910 // need to be changed with DeclGroups. 2911 if (TK == TK_Reference) 2912 return PrevDecl; 2913 2914 // Diagnose attempts to redefine a tag. 2915 if (TK == TK_Definition) { 2916 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2917 Diag(NameLoc, diag::err_redefinition) << Name; 2918 Diag(Def->getLocation(), diag::note_previous_definition); 2919 // If this is a redefinition, recover by making this 2920 // struct be anonymous, which will make any later 2921 // references get the previous definition. 2922 Name = 0; 2923 PrevDecl = 0; 2924 Invalid = true; 2925 } else { 2926 // If the type is currently being defined, complain 2927 // about a nested redefinition. 2928 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2929 if (Tag->isBeingDefined()) { 2930 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2931 Diag(PrevTagDecl->getLocation(), 2932 diag::note_previous_definition); 2933 Name = 0; 2934 PrevDecl = 0; 2935 Invalid = true; 2936 } 2937 } 2938 2939 // Okay, this is definition of a previously declared or referenced 2940 // tag PrevDecl. We're going to create a new Decl for it. 2941 } 2942 } 2943 // If we get here we have (another) forward declaration or we 2944 // have a definition. Just create a new decl. 2945 } else { 2946 // If we get here, this is a definition of a new tag type in a nested 2947 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2948 // new decl/type. We set PrevDecl to NULL so that the entities 2949 // have distinct types. 2950 PrevDecl = 0; 2951 } 2952 // If we get here, we're going to create a new Decl. If PrevDecl 2953 // is non-NULL, it's a definition of the tag declared by 2954 // PrevDecl. If it's NULL, we have a new definition. 2955 } else { 2956 // PrevDecl is a namespace. 2957 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2958 // The tag name clashes with a namespace name, issue an error and 2959 // recover by making this tag be anonymous. 2960 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2961 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2962 Name = 0; 2963 PrevDecl = 0; 2964 Invalid = true; 2965 } else { 2966 // The existing declaration isn't relevant to us; we're in a 2967 // new scope, so clear out the previous declaration. 2968 PrevDecl = 0; 2969 } 2970 } 2971 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2972 (Kind != TagDecl::TK_enum)) { 2973 // C++ [basic.scope.pdecl]p5: 2974 // -- for an elaborated-type-specifier of the form 2975 // 2976 // class-key identifier 2977 // 2978 // if the elaborated-type-specifier is used in the 2979 // decl-specifier-seq or parameter-declaration-clause of a 2980 // function defined in namespace scope, the identifier is 2981 // declared as a class-name in the namespace that contains 2982 // the declaration; otherwise, except as a friend 2983 // declaration, the identifier is declared in the smallest 2984 // non-class, non-function-prototype scope that contains the 2985 // declaration. 2986 // 2987 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2988 // C structs and unions. 2989 2990 // Find the context where we'll be declaring the tag. 2991 // FIXME: We would like to maintain the current DeclContext as the 2992 // lexical context, 2993 while (DC->isRecord()) 2994 DC = DC->getParent(); 2995 LexicalContext = DC; 2996 2997 // Find the scope where we'll be declaring the tag. 2998 while (S->isClassScope() || 2999 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3000 ((S->getFlags() & Scope::DeclScope) == 0) || 3001 (S->getEntity() && 3002 ((DeclContext *)S->getEntity())->isTransparentContext())) 3003 S = S->getParent(); 3004 } 3005 3006CreateNewDecl: 3007 3008 // If there is an identifier, use the location of the identifier as the 3009 // location of the decl, otherwise use the location of the struct/union 3010 // keyword. 3011 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3012 3013 // Otherwise, create a new declaration. If there is a previous 3014 // declaration of the same entity, the two will be linked via 3015 // PrevDecl. 3016 TagDecl *New; 3017 3018 if (Kind == TagDecl::TK_enum) { 3019 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3020 // enum X { A, B, C } D; D should chain to X. 3021 New = EnumDecl::Create(Context, DC, Loc, Name, 3022 cast_or_null<EnumDecl>(PrevDecl)); 3023 // If this is an undefined enum, warn. 3024 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3025 } else { 3026 // struct/union/class 3027 3028 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3029 // struct X { int A; } D; D should chain to X. 3030 if (getLangOptions().CPlusPlus) 3031 // FIXME: Look for a way to use RecordDecl for simple structs. 3032 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 3033 cast_or_null<CXXRecordDecl>(PrevDecl)); 3034 else 3035 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 3036 cast_or_null<RecordDecl>(PrevDecl)); 3037 } 3038 3039 if (Kind != TagDecl::TK_enum) { 3040 // Handle #pragma pack: if the #pragma pack stack has non-default 3041 // alignment, make up a packed attribute for this decl. These 3042 // attributes are checked when the ASTContext lays out the 3043 // structure. 3044 // 3045 // It is important for implementing the correct semantics that this 3046 // happen here (in act on tag decl). The #pragma pack stack is 3047 // maintained as a result of parser callbacks which can occur at 3048 // many points during the parsing of a struct declaration (because 3049 // the #pragma tokens are effectively skipped over during the 3050 // parsing of the struct). 3051 if (unsigned Alignment = PackContext.getAlignment()) 3052 New->addAttr(new PackedAttr(Alignment * 8)); 3053 } 3054 3055 if (Invalid) 3056 New->setInvalidDecl(); 3057 3058 if (Attr) 3059 ProcessDeclAttributeList(New, Attr); 3060 3061 // If we're declaring or defining a tag in function prototype scope 3062 // in C, note that this type can only be used within the function. 3063 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3064 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3065 3066 // Set the lexical context. If the tag has a C++ scope specifier, the 3067 // lexical context will be different from the semantic context. 3068 New->setLexicalDeclContext(LexicalContext); 3069 3070 if (TK == TK_Definition) 3071 New->startDefinition(); 3072 3073 // If this has an identifier, add it to the scope stack. 3074 if (Name) { 3075 S = getNonFieldDeclScope(S); 3076 3077 // Add it to the decl chain. 3078 if (LexicalContext != CurContext) { 3079 // FIXME: PushOnScopeChains should not rely on CurContext! 3080 DeclContext *OldContext = CurContext; 3081 CurContext = LexicalContext; 3082 PushOnScopeChains(New, S); 3083 CurContext = OldContext; 3084 } else 3085 PushOnScopeChains(New, S); 3086 } else { 3087 LexicalContext->addDecl(New); 3088 } 3089 3090 return New; 3091} 3092 3093void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3094 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3095 3096 // Enter the tag context. 3097 PushDeclContext(S, Tag); 3098 3099 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3100 FieldCollector->StartClass(); 3101 3102 if (Record->getIdentifier()) { 3103 // C++ [class]p2: 3104 // [...] The class-name is also inserted into the scope of the 3105 // class itself; this is known as the injected-class-name. For 3106 // purposes of access checking, the injected-class-name is treated 3107 // as if it were a public member name. 3108 RecordDecl *InjectedClassName 3109 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3110 CurContext, Record->getLocation(), 3111 Record->getIdentifier(), Record); 3112 InjectedClassName->setImplicit(); 3113 PushOnScopeChains(InjectedClassName, S); 3114 } 3115 } 3116} 3117 3118void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3119 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3120 3121 if (isa<CXXRecordDecl>(Tag)) 3122 FieldCollector->FinishClass(); 3123 3124 // Exit this scope of this tag's definition. 3125 PopDeclContext(); 3126 3127 // Notify the consumer that we've defined a tag. 3128 Consumer.HandleTagDeclDefinition(Tag); 3129} 3130 3131/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3132/// types into constant array types in certain situations which would otherwise 3133/// be errors (for GCC compatibility). 3134static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3135 ASTContext &Context) { 3136 // This method tries to turn a variable array into a constant 3137 // array even when the size isn't an ICE. This is necessary 3138 // for compatibility with code that depends on gcc's buggy 3139 // constant expression folding, like struct {char x[(int)(char*)2];} 3140 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3141 if (!VLATy) return QualType(); 3142 3143 Expr::EvalResult EvalResult; 3144 if (!VLATy->getSizeExpr() || 3145 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3146 return QualType(); 3147 3148 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3149 llvm::APSInt &Res = EvalResult.Val.getInt(); 3150 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3151 return Context.getConstantArrayType(VLATy->getElementType(), 3152 Res, ArrayType::Normal, 0); 3153 return QualType(); 3154} 3155 3156bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3157 QualType FieldTy, const Expr *BitWidth) { 3158 // FIXME: 6.7.2.1p4 - verify the field type. 3159 3160 llvm::APSInt Value; 3161 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3162 return true; 3163 3164 // Zero-width bitfield is ok for anonymous field. 3165 if (Value == 0 && FieldName) 3166 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3167 3168 if (Value.isNegative()) 3169 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3170 3171 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3172 // FIXME: We won't need the 0 size once we check that the field type is valid. 3173 if (TypeSize && Value.getZExtValue() > TypeSize) 3174 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3175 << FieldName << (unsigned)TypeSize; 3176 3177 return false; 3178} 3179 3180/// ActOnField - Each field of a struct/union/class is passed into this in order 3181/// to create a FieldDecl object for it. 3182Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3183 SourceLocation DeclStart, 3184 Declarator &D, ExprTy *BitfieldWidth) { 3185 IdentifierInfo *II = D.getIdentifier(); 3186 Expr *BitWidth = (Expr*)BitfieldWidth; 3187 SourceLocation Loc = DeclStart; 3188 RecordDecl *Record = (RecordDecl *)TagD; 3189 if (II) Loc = D.getIdentifierLoc(); 3190 3191 // FIXME: Unnamed fields can be handled in various different ways, for 3192 // example, unnamed unions inject all members into the struct namespace! 3193 3194 QualType T = GetTypeForDeclarator(D, S); 3195 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3196 bool InvalidDecl = false; 3197 3198 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3199 // than a variably modified type. 3200 if (T->isVariablyModifiedType()) { 3201 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3202 if (!FixedTy.isNull()) { 3203 Diag(Loc, diag::warn_illegal_constant_array_size); 3204 T = FixedTy; 3205 } else { 3206 Diag(Loc, diag::err_typecheck_field_variable_size); 3207 T = Context.IntTy; 3208 InvalidDecl = true; 3209 } 3210 } 3211 3212 if (BitWidth) { 3213 if (VerifyBitField(Loc, II, T, BitWidth)) 3214 InvalidDecl = true; 3215 } else { 3216 // Not a bitfield. 3217 3218 // validate II. 3219 3220 } 3221 3222 // FIXME: Chain fielddecls together. 3223 FieldDecl *NewFD; 3224 3225 NewFD = FieldDecl::Create(Context, Record, 3226 Loc, II, T, BitWidth, 3227 D.getDeclSpec().getStorageClassSpec() == 3228 DeclSpec::SCS_mutable, 3229 /*PrevDecl=*/0); 3230 3231 if (II) { 3232 Decl *PrevDecl 3233 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3234 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3235 && !isa<TagDecl>(PrevDecl)) { 3236 Diag(Loc, diag::err_duplicate_member) << II; 3237 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3238 NewFD->setInvalidDecl(); 3239 Record->setInvalidDecl(); 3240 } 3241 } 3242 3243 if (getLangOptions().CPlusPlus) { 3244 CheckExtraCXXDefaultArguments(D); 3245 if (!T->isPODType()) 3246 cast<CXXRecordDecl>(Record)->setPOD(false); 3247 } 3248 3249 ProcessDeclAttributes(NewFD, D); 3250 3251 if (D.getInvalidType() || InvalidDecl) 3252 NewFD->setInvalidDecl(); 3253 3254 if (II) { 3255 PushOnScopeChains(NewFD, S); 3256 } else 3257 Record->addDecl(NewFD); 3258 3259 return NewFD; 3260} 3261 3262/// TranslateIvarVisibility - Translate visibility from a token ID to an 3263/// AST enum value. 3264static ObjCIvarDecl::AccessControl 3265TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3266 switch (ivarVisibility) { 3267 default: assert(0 && "Unknown visitibility kind"); 3268 case tok::objc_private: return ObjCIvarDecl::Private; 3269 case tok::objc_public: return ObjCIvarDecl::Public; 3270 case tok::objc_protected: return ObjCIvarDecl::Protected; 3271 case tok::objc_package: return ObjCIvarDecl::Package; 3272 } 3273} 3274 3275/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3276/// in order to create an IvarDecl object for it. 3277Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3278 SourceLocation DeclStart, 3279 Declarator &D, ExprTy *BitfieldWidth, 3280 tok::ObjCKeywordKind Visibility) { 3281 3282 IdentifierInfo *II = D.getIdentifier(); 3283 Expr *BitWidth = (Expr*)BitfieldWidth; 3284 SourceLocation Loc = DeclStart; 3285 if (II) Loc = D.getIdentifierLoc(); 3286 3287 // FIXME: Unnamed fields can be handled in various different ways, for 3288 // example, unnamed unions inject all members into the struct namespace! 3289 3290 QualType T = GetTypeForDeclarator(D, S); 3291 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3292 bool InvalidDecl = false; 3293 3294 if (BitWidth) { 3295 // TODO: Validate. 3296 //printf("WARNING: BITFIELDS IGNORED!\n"); 3297 3298 // 6.7.2.1p3 3299 // 6.7.2.1p4 3300 3301 } else { 3302 // Not a bitfield. 3303 3304 // validate II. 3305 3306 } 3307 3308 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3309 // than a variably modified type. 3310 if (T->isVariablyModifiedType()) { 3311 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3312 InvalidDecl = true; 3313 } 3314 3315 // Get the visibility (access control) for this ivar. 3316 ObjCIvarDecl::AccessControl ac = 3317 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3318 : ObjCIvarDecl::None; 3319 3320 // Construct the decl. 3321 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3322 (Expr *)BitfieldWidth); 3323 3324 if (II) { 3325 Decl *PrevDecl 3326 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3327 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3328 && !isa<TagDecl>(PrevDecl)) { 3329 Diag(Loc, diag::err_duplicate_member) << II; 3330 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3331 NewID->setInvalidDecl(); 3332 } 3333 } 3334 3335 // Process attributes attached to the ivar. 3336 ProcessDeclAttributes(NewID, D); 3337 3338 if (D.getInvalidType() || InvalidDecl) 3339 NewID->setInvalidDecl(); 3340 3341 if (II) { 3342 // FIXME: When interfaces are DeclContexts, we'll need to add 3343 // these to the interface. 3344 S->AddDecl(NewID); 3345 IdResolver.AddDecl(NewID); 3346 } 3347 3348 return NewID; 3349} 3350 3351void Sema::ActOnFields(Scope* S, 3352 SourceLocation RecLoc, DeclTy *RecDecl, 3353 DeclTy **Fields, unsigned NumFields, 3354 SourceLocation LBrac, SourceLocation RBrac, 3355 AttributeList *Attr) { 3356 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3357 assert(EnclosingDecl && "missing record or interface decl"); 3358 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3359 3360 // Verify that all the fields are okay. 3361 unsigned NumNamedMembers = 0; 3362 llvm::SmallVector<FieldDecl*, 32> RecFields; 3363 3364 for (unsigned i = 0; i != NumFields; ++i) { 3365 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3366 assert(FD && "missing field decl"); 3367 3368 // Get the type for the field. 3369 Type *FDTy = FD->getType().getTypePtr(); 3370 3371 if (!FD->isAnonymousStructOrUnion()) { 3372 // Remember all fields written by the user. 3373 RecFields.push_back(FD); 3374 } 3375 3376 // C99 6.7.2.1p2 - A field may not be a function type. 3377 if (FDTy->isFunctionType()) { 3378 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3379 << FD->getDeclName(); 3380 FD->setInvalidDecl(); 3381 EnclosingDecl->setInvalidDecl(); 3382 continue; 3383 } 3384 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3385 if (FDTy->isIncompleteType()) { 3386 if (!Record) { // Incomplete ivar type is always an error. 3387 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3388 FD->setInvalidDecl(); 3389 EnclosingDecl->setInvalidDecl(); 3390 continue; 3391 } 3392 if (i != NumFields-1 || // ... that the last member ... 3393 !Record->isStruct() || // ... of a structure ... 3394 !FDTy->isArrayType()) { //... may have incomplete array type. 3395 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3396 FD->setInvalidDecl(); 3397 EnclosingDecl->setInvalidDecl(); 3398 continue; 3399 } 3400 if (NumNamedMembers < 1) { //... must have more than named member ... 3401 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3402 << FD->getDeclName(); 3403 FD->setInvalidDecl(); 3404 EnclosingDecl->setInvalidDecl(); 3405 continue; 3406 } 3407 // Okay, we have a legal flexible array member at the end of the struct. 3408 if (Record) 3409 Record->setHasFlexibleArrayMember(true); 3410 } 3411 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3412 /// field of another structure or the element of an array. 3413 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3414 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3415 // If this is a member of a union, then entire union becomes "flexible". 3416 if (Record && Record->isUnion()) { 3417 Record->setHasFlexibleArrayMember(true); 3418 } else { 3419 // If this is a struct/class and this is not the last element, reject 3420 // it. Note that GCC supports variable sized arrays in the middle of 3421 // structures. 3422 if (i != NumFields-1) { 3423 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3424 << FD->getDeclName(); 3425 FD->setInvalidDecl(); 3426 EnclosingDecl->setInvalidDecl(); 3427 continue; 3428 } 3429 // We support flexible arrays at the end of structs in other structs 3430 // as an extension. 3431 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3432 << FD->getDeclName(); 3433 if (Record) 3434 Record->setHasFlexibleArrayMember(true); 3435 } 3436 } 3437 } 3438 /// A field cannot be an Objective-c object 3439 if (FDTy->isObjCInterfaceType()) { 3440 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3441 << FD->getDeclName(); 3442 FD->setInvalidDecl(); 3443 EnclosingDecl->setInvalidDecl(); 3444 continue; 3445 } 3446 // Keep track of the number of named members. 3447 if (FD->getIdentifier()) 3448 ++NumNamedMembers; 3449 } 3450 3451 // Okay, we successfully defined 'Record'. 3452 if (Record) { 3453 Record->completeDefinition(Context); 3454 } else { 3455 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3456 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3457 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3458 // Must enforce the rule that ivars in the base classes may not be 3459 // duplicates. 3460 if (ID->getSuperClass()) { 3461 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3462 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3463 ObjCIvarDecl* Ivar = (*IVI); 3464 IdentifierInfo *II = Ivar->getIdentifier(); 3465 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3466 if (prevIvar) { 3467 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3468 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3469 } 3470 } 3471 } 3472 } 3473 else if (ObjCImplementationDecl *IMPDecl = 3474 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3475 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3476 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3477 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3478 } 3479 } 3480 3481 if (Attr) 3482 ProcessDeclAttributeList(Record, Attr); 3483} 3484 3485Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3486 DeclTy *lastEnumConst, 3487 SourceLocation IdLoc, IdentifierInfo *Id, 3488 SourceLocation EqualLoc, ExprTy *val) { 3489 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3490 EnumConstantDecl *LastEnumConst = 3491 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3492 Expr *Val = static_cast<Expr*>(val); 3493 3494 // The scope passed in may not be a decl scope. Zip up the scope tree until 3495 // we find one that is. 3496 S = getNonFieldDeclScope(S); 3497 3498 // Verify that there isn't already something declared with this name in this 3499 // scope. 3500 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3501 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3502 // Maybe we will complain about the shadowed template parameter. 3503 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3504 // Just pretend that we didn't see the previous declaration. 3505 PrevDecl = 0; 3506 } 3507 3508 if (PrevDecl) { 3509 // When in C++, we may get a TagDecl with the same name; in this case the 3510 // enum constant will 'hide' the tag. 3511 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3512 "Received TagDecl when not in C++!"); 3513 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3514 if (isa<EnumConstantDecl>(PrevDecl)) 3515 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3516 else 3517 Diag(IdLoc, diag::err_redefinition) << Id; 3518 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3519 delete Val; 3520 return 0; 3521 } 3522 } 3523 3524 llvm::APSInt EnumVal(32); 3525 QualType EltTy; 3526 if (Val) { 3527 // Make sure to promote the operand type to int. 3528 UsualUnaryConversions(Val); 3529 3530 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3531 SourceLocation ExpLoc; 3532 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3533 delete Val; 3534 Val = 0; // Just forget about it. 3535 } else { 3536 EltTy = Val->getType(); 3537 } 3538 } 3539 3540 if (!Val) { 3541 if (LastEnumConst) { 3542 // Assign the last value + 1. 3543 EnumVal = LastEnumConst->getInitVal(); 3544 ++EnumVal; 3545 3546 // Check for overflow on increment. 3547 if (EnumVal < LastEnumConst->getInitVal()) 3548 Diag(IdLoc, diag::warn_enum_value_overflow); 3549 3550 EltTy = LastEnumConst->getType(); 3551 } else { 3552 // First value, set to zero. 3553 EltTy = Context.IntTy; 3554 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3555 } 3556 } 3557 3558 EnumConstantDecl *New = 3559 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3560 Val, EnumVal, 3561 LastEnumConst); 3562 3563 // Register this decl in the current scope stack. 3564 PushOnScopeChains(New, S); 3565 3566 return New; 3567} 3568 3569// FIXME: For consistency with ActOnFields(), we should have the parser 3570// pass in the source location for the left/right braces. 3571void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3572 DeclTy **Elements, unsigned NumElements) { 3573 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3574 QualType EnumType = Context.getTypeDeclType(Enum); 3575 3576 // TODO: If the result value doesn't fit in an int, it must be a long or long 3577 // long value. ISO C does not support this, but GCC does as an extension, 3578 // emit a warning. 3579 unsigned IntWidth = Context.Target.getIntWidth(); 3580 3581 // Verify that all the values are okay, compute the size of the values, and 3582 // reverse the list. 3583 unsigned NumNegativeBits = 0; 3584 unsigned NumPositiveBits = 0; 3585 3586 // Keep track of whether all elements have type int. 3587 bool AllElementsInt = true; 3588 3589 for (unsigned i = 0; i != NumElements; ++i) { 3590 EnumConstantDecl *ECD = 3591 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3592 if (!ECD) continue; // Already issued a diagnostic. 3593 3594 // If the enum value doesn't fit in an int, emit an extension warning. 3595 const llvm::APSInt &InitVal = ECD->getInitVal(); 3596 assert(InitVal.getBitWidth() >= IntWidth && 3597 "Should have promoted value to int"); 3598 if (InitVal.getBitWidth() > IntWidth) { 3599 llvm::APSInt V(InitVal); 3600 V.trunc(IntWidth); 3601 V.extend(InitVal.getBitWidth()); 3602 if (V != InitVal) 3603 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3604 << InitVal.toString(10); 3605 } 3606 3607 // Keep track of the size of positive and negative values. 3608 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3609 NumPositiveBits = std::max(NumPositiveBits, 3610 (unsigned)InitVal.getActiveBits()); 3611 else 3612 NumNegativeBits = std::max(NumNegativeBits, 3613 (unsigned)InitVal.getMinSignedBits()); 3614 3615 // Keep track of whether every enum element has type int (very commmon). 3616 if (AllElementsInt) 3617 AllElementsInt = ECD->getType() == Context.IntTy; 3618 } 3619 3620 // Figure out the type that should be used for this enum. 3621 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3622 QualType BestType; 3623 unsigned BestWidth; 3624 3625 if (NumNegativeBits) { 3626 // If there is a negative value, figure out the smallest integer type (of 3627 // int/long/longlong) that fits. 3628 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3629 BestType = Context.IntTy; 3630 BestWidth = IntWidth; 3631 } else { 3632 BestWidth = Context.Target.getLongWidth(); 3633 3634 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3635 BestType = Context.LongTy; 3636 else { 3637 BestWidth = Context.Target.getLongLongWidth(); 3638 3639 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3640 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3641 BestType = Context.LongLongTy; 3642 } 3643 } 3644 } else { 3645 // If there is no negative value, figure out which of uint, ulong, ulonglong 3646 // fits. 3647 if (NumPositiveBits <= IntWidth) { 3648 BestType = Context.UnsignedIntTy; 3649 BestWidth = IntWidth; 3650 } else if (NumPositiveBits <= 3651 (BestWidth = Context.Target.getLongWidth())) { 3652 BestType = Context.UnsignedLongTy; 3653 } else { 3654 BestWidth = Context.Target.getLongLongWidth(); 3655 assert(NumPositiveBits <= BestWidth && 3656 "How could an initializer get larger than ULL?"); 3657 BestType = Context.UnsignedLongLongTy; 3658 } 3659 } 3660 3661 // Loop over all of the enumerator constants, changing their types to match 3662 // the type of the enum if needed. 3663 for (unsigned i = 0; i != NumElements; ++i) { 3664 EnumConstantDecl *ECD = 3665 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3666 if (!ECD) continue; // Already issued a diagnostic. 3667 3668 // Standard C says the enumerators have int type, but we allow, as an 3669 // extension, the enumerators to be larger than int size. If each 3670 // enumerator value fits in an int, type it as an int, otherwise type it the 3671 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3672 // that X has type 'int', not 'unsigned'. 3673 if (ECD->getType() == Context.IntTy) { 3674 // Make sure the init value is signed. 3675 llvm::APSInt IV = ECD->getInitVal(); 3676 IV.setIsSigned(true); 3677 ECD->setInitVal(IV); 3678 3679 if (getLangOptions().CPlusPlus) 3680 // C++ [dcl.enum]p4: Following the closing brace of an 3681 // enum-specifier, each enumerator has the type of its 3682 // enumeration. 3683 ECD->setType(EnumType); 3684 continue; // Already int type. 3685 } 3686 3687 // Determine whether the value fits into an int. 3688 llvm::APSInt InitVal = ECD->getInitVal(); 3689 bool FitsInInt; 3690 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3691 FitsInInt = InitVal.getActiveBits() < IntWidth; 3692 else 3693 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3694 3695 // If it fits into an integer type, force it. Otherwise force it to match 3696 // the enum decl type. 3697 QualType NewTy; 3698 unsigned NewWidth; 3699 bool NewSign; 3700 if (FitsInInt) { 3701 NewTy = Context.IntTy; 3702 NewWidth = IntWidth; 3703 NewSign = true; 3704 } else if (ECD->getType() == BestType) { 3705 // Already the right type! 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 continue; 3712 } else { 3713 NewTy = BestType; 3714 NewWidth = BestWidth; 3715 NewSign = BestType->isSignedIntegerType(); 3716 } 3717 3718 // Adjust the APSInt value. 3719 InitVal.extOrTrunc(NewWidth); 3720 InitVal.setIsSigned(NewSign); 3721 ECD->setInitVal(InitVal); 3722 3723 // Adjust the Expr initializer and type. 3724 if (ECD->getInitExpr()) 3725 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3726 /*isLvalue=*/false)); 3727 if (getLangOptions().CPlusPlus) 3728 // C++ [dcl.enum]p4: Following the closing brace of an 3729 // enum-specifier, each enumerator has the type of its 3730 // enumeration. 3731 ECD->setType(EnumType); 3732 else 3733 ECD->setType(NewTy); 3734 } 3735 3736 Enum->completeDefinition(Context, BestType); 3737} 3738 3739Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3740 ExprArg expr) { 3741 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3742 3743 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3744} 3745 3746 3747void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3748 ExprTy *alignment, SourceLocation PragmaLoc, 3749 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3750 Expr *Alignment = static_cast<Expr *>(alignment); 3751 3752 // If specified then alignment must be a "small" power of two. 3753 unsigned AlignmentVal = 0; 3754 if (Alignment) { 3755 llvm::APSInt Val; 3756 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3757 !Val.isPowerOf2() || 3758 Val.getZExtValue() > 16) { 3759 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3760 delete Alignment; 3761 return; // Ignore 3762 } 3763 3764 AlignmentVal = (unsigned) Val.getZExtValue(); 3765 } 3766 3767 switch (Kind) { 3768 case Action::PPK_Default: // pack([n]) 3769 PackContext.setAlignment(AlignmentVal); 3770 break; 3771 3772 case Action::PPK_Show: // pack(show) 3773 // Show the current alignment, making sure to show the right value 3774 // for the default. 3775 AlignmentVal = PackContext.getAlignment(); 3776 // FIXME: This should come from the target. 3777 if (AlignmentVal == 0) 3778 AlignmentVal = 8; 3779 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3780 break; 3781 3782 case Action::PPK_Push: // pack(push [, id] [, [n]) 3783 PackContext.push(Name); 3784 // Set the new alignment if specified. 3785 if (Alignment) 3786 PackContext.setAlignment(AlignmentVal); 3787 break; 3788 3789 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3790 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3791 // "#pragma pack(pop, identifier, n) is undefined" 3792 if (Alignment && Name) 3793 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3794 3795 // Do the pop. 3796 if (!PackContext.pop(Name)) { 3797 // If a name was specified then failure indicates the name 3798 // wasn't found. Otherwise failure indicates the stack was 3799 // empty. 3800 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3801 << (Name ? "no record matching name" : "stack empty"); 3802 3803 // FIXME: Warn about popping named records as MSVC does. 3804 } else { 3805 // Pop succeeded, set the new alignment if specified. 3806 if (Alignment) 3807 PackContext.setAlignment(AlignmentVal); 3808 } 3809 break; 3810 3811 default: 3812 assert(0 && "Invalid #pragma pack kind."); 3813 } 3814} 3815 3816bool PragmaPackStack::pop(IdentifierInfo *Name) { 3817 if (Stack.empty()) 3818 return false; 3819 3820 // If name is empty just pop top. 3821 if (!Name) { 3822 Alignment = Stack.back().first; 3823 Stack.pop_back(); 3824 return true; 3825 } 3826 3827 // Otherwise, find the named record. 3828 for (unsigned i = Stack.size(); i != 0; ) { 3829 --i; 3830 if (Stack[i].second == Name) { 3831 // Found it, pop up to and including this record. 3832 Alignment = Stack[i].first; 3833 Stack.erase(Stack.begin() + i, Stack.end()); 3834 return true; 3835 } 3836 } 3837 3838 return false; 3839} 3840