SemaDecl.cpp revision 4111024be81e7c0525e42dadcc126d27e5bf2425
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/ASTConsumer.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/Attr.h" 18#include "clang/AST/Builtins.h" 19#include "clang/AST/Decl.h" 20#include "clang/AST/DeclCXX.h" 21#include "clang/AST/Expr.h" 22#include "clang/AST/Type.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Parse/Scope.h" 25#include "clang/Basic/LangOptions.h" 26#include "clang/Basic/TargetInfo.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/AST/ExprCXX.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/SmallString.h" 33#include "llvm/ADT/SmallSet.h" 34#include "llvm/ADT/DenseSet.h" 35using namespace clang; 36 37Sema::DeclTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 38 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 39 40 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 41 isa<ObjCInterfaceDecl>(IIDecl) || 42 isa<TagDecl>(IIDecl))) 43 return IIDecl; 44 return 0; 45} 46 47void Sema::PushDeclContext(DeclContext *DC) { 48 assert( ( (isa<ObjCMethodDecl>(DC) && isa<TranslationUnitDecl>(CurContext)) 49 || DC->getParent() == CurContext ) && 50 "The next DeclContext should be directly contained in the current one."); 51 CurContext = DC; 52} 53 54void Sema::PopDeclContext() { 55 assert(CurContext && "DeclContext imbalance!"); 56 // If CurContext is a ObjC method, getParent() will return NULL. 57 CurContext = isa<ObjCMethodDecl>(CurContext) 58 ? Context.getTranslationUnitDecl() 59 : CurContext->getParent(); 60} 61 62/// Add this decl to the scope shadowed decl chains. 63void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 64 S->AddDecl(D); 65 66 // C++ [basic.scope]p4: 67 // -- exactly one declaration shall declare a class name or 68 // enumeration name that is not a typedef name and the other 69 // declarations shall all refer to the same object or 70 // enumerator, or all refer to functions and function templates; 71 // in this case the class name or enumeration name is hidden. 72 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 73 // We are pushing the name of a tag (enum or class). 74 IdentifierResolver::ctx_iterator 75 CIT = IdResolver.ctx_begin(TD->getIdentifier(), TD->getDeclContext()); 76 if (CIT != IdResolver.ctx_end(TD->getIdentifier()) && 77 IdResolver.isDeclInScope(*CIT, TD->getDeclContext(), S)) { 78 // There is already a declaration with the same name in the same 79 // scope. It must be found before we find the new declaration, 80 // so swap the order on the shadowed declaration chain. 81 82 IdResolver.AddShadowedDecl(TD, *CIT); 83 return; 84 } 85 } 86 87 IdResolver.AddDecl(D); 88} 89 90void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 91 if (S->decl_empty()) return; 92 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 93 94 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 95 I != E; ++I) { 96 Decl *TmpD = static_cast<Decl*>(*I); 97 assert(TmpD && "This decl didn't get pushed??"); 98 99 if (isa<CXXFieldDecl>(TmpD)) continue; 100 101 assert(isa<ScopedDecl>(TmpD) && "Decl isn't ScopedDecl?"); 102 ScopedDecl *D = cast<ScopedDecl>(TmpD); 103 104 IdentifierInfo *II = D->getIdentifier(); 105 if (!II) continue; 106 107 // We only want to remove the decls from the identifier decl chains for local 108 // scopes, when inside a function/method. 109 if (S->getFnParent() != 0) 110 IdResolver.RemoveDecl(D); 111 112 // Chain this decl to the containing DeclContext. 113 D->setNext(CurContext->getDeclChain()); 114 CurContext->setDeclChain(D); 115 } 116} 117 118/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 119/// return 0 if one not found. 120ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 121 // The third "scope" argument is 0 since we aren't enabling lazy built-in 122 // creation from this context. 123 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 124 125 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 126} 127 128/// LookupDecl - Look up the inner-most declaration in the specified 129/// namespace. 130Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 131 Scope *S, bool enableLazyBuiltinCreation) { 132 if (II == 0) return 0; 133 unsigned NS = NSI; 134 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 135 NS |= Decl::IDNS_Tag; 136 137 // Scan up the scope chain looking for a decl that matches this identifier 138 // that is in the appropriate namespace. This search should not take long, as 139 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 140 for (IdentifierResolver::iterator 141 I = IdResolver.begin(II, CurContext), E = IdResolver.end(II); I != E; ++I) 142 if ((*I)->getIdentifierNamespace() & NS) 143 return *I; 144 145 // If we didn't find a use of this identifier, and if the identifier 146 // corresponds to a compiler builtin, create the decl object for the builtin 147 // now, injecting it into translation unit scope, and return it. 148 if (NS & Decl::IDNS_Ordinary) { 149 if (enableLazyBuiltinCreation) { 150 // If this is a builtin on this (or all) targets, create the decl. 151 if (unsigned BuiltinID = II->getBuiltinID()) 152 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 153 } 154 if (getLangOptions().ObjC1) { 155 // @interface and @compatibility_alias introduce typedef-like names. 156 // Unlike typedef's, they can only be introduced at file-scope (and are 157 // therefore not scoped decls). They can, however, be shadowed by 158 // other names in IDNS_Ordinary. 159 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 160 if (IDI != ObjCInterfaceDecls.end()) 161 return IDI->second; 162 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 163 if (I != ObjCAliasDecls.end()) 164 return I->second->getClassInterface(); 165 } 166 } 167 return 0; 168} 169 170void Sema::InitBuiltinVaListType() { 171 if (!Context.getBuiltinVaListType().isNull()) 172 return; 173 174 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 175 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 176 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 177 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 178} 179 180/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 181/// lazily create a decl for it. 182ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 183 Scope *S) { 184 Builtin::ID BID = (Builtin::ID)bid; 185 186 if (BID == Builtin::BI__builtin_va_start || 187 BID == Builtin::BI__builtin_va_copy || 188 BID == Builtin::BI__builtin_va_end) 189 InitBuiltinVaListType(); 190 191 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 192 FunctionDecl *New = FunctionDecl::Create(Context, 193 Context.getTranslationUnitDecl(), 194 SourceLocation(), II, R, 195 FunctionDecl::Extern, false, 0); 196 197 // Create Decl objects for each parameter, adding them to the 198 // FunctionDecl. 199 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 200 llvm::SmallVector<ParmVarDecl*, 16> Params; 201 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 202 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 203 FT->getArgType(i), VarDecl::None, 0, 204 0)); 205 New->setParams(&Params[0], Params.size()); 206 } 207 208 209 210 // TUScope is the translation-unit scope to insert this function into. 211 PushOnScopeChains(New, TUScope); 212 return New; 213} 214 215/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 216/// and scope as a previous declaration 'Old'. Figure out how to resolve this 217/// situation, merging decls or emitting diagnostics as appropriate. 218/// 219TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 220 // Verify the old decl was also a typedef. 221 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 222 if (!Old) { 223 Diag(New->getLocation(), diag::err_redefinition_different_kind, 224 New->getName()); 225 Diag(OldD->getLocation(), diag::err_previous_definition); 226 return New; 227 } 228 229 // Allow multiple definitions for ObjC built-in typedefs. 230 // FIXME: Verify the underlying types are equivalent! 231 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 232 return Old; 233 234 if (getLangOptions().Microsoft) return New; 235 236 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 237 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 238 // *either* declaration is in a system header. The code below implements 239 // this adhoc compatibility rule. FIXME: The following code will not 240 // work properly when compiling ".i" files (containing preprocessed output). 241 SourceManager &SrcMgr = Context.getSourceManager(); 242 HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); 243 const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); 244 if (OldDeclFile) { 245 DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); 246 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 247 if (OldDirType != DirectoryLookup::NormalHeaderDir) 248 return New; 249 } 250 const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); 251 if (NewDeclFile) { 252 DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); 253 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 254 if (NewDirType != DirectoryLookup::NormalHeaderDir) 255 return New; 256 } 257 258 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 259 Diag(Old->getLocation(), diag::err_previous_definition); 260 return New; 261} 262 263/// DeclhasAttr - returns true if decl Declaration already has the target attribute. 264static bool DeclHasAttr(const Decl *decl, const Attr *target) { 265 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 266 if (attr->getKind() == target->getKind()) 267 return true; 268 269 return false; 270} 271 272/// MergeAttributes - append attributes from the Old decl to the New one. 273static void MergeAttributes(Decl *New, Decl *Old) { 274 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 275 276 while (attr) { 277 tmp = attr; 278 attr = attr->getNext(); 279 280 if (!DeclHasAttr(New, tmp)) { 281 New->addAttr(tmp); 282 } else { 283 tmp->setNext(0); 284 delete(tmp); 285 } 286 } 287 288 Old->invalidateAttrs(); 289} 290 291/// MergeFunctionDecl - We just parsed a function 'New' from 292/// declarator D which has the same name and scope as a previous 293/// declaration 'Old'. Figure out how to resolve this situation, 294/// merging decls or emitting diagnostics as appropriate. 295/// Redeclaration will be set true if thisNew is a redeclaration OldD. 296FunctionDecl * 297Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 298 Redeclaration = false; 299 // Verify the old decl was also a function. 300 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 301 if (!Old) { 302 Diag(New->getLocation(), diag::err_redefinition_different_kind, 303 New->getName()); 304 Diag(OldD->getLocation(), diag::err_previous_definition); 305 return New; 306 } 307 308 QualType OldQType = Context.getCanonicalType(Old->getType()); 309 QualType NewQType = Context.getCanonicalType(New->getType()); 310 311 // C++ [dcl.fct]p3: 312 // All declarations for a function shall agree exactly in both the 313 // return type and the parameter-type-list. 314 if (getLangOptions().CPlusPlus && OldQType == NewQType) { 315 MergeAttributes(New, Old); 316 Redeclaration = true; 317 return MergeCXXFunctionDecl(New, Old); 318 } 319 320 // C: Function types need to be compatible, not identical. This handles 321 // duplicate function decls like "void f(int); void f(enum X);" properly. 322 if (!getLangOptions().CPlusPlus && 323 Context.functionTypesAreCompatible(OldQType, NewQType)) { 324 MergeAttributes(New, Old); 325 Redeclaration = true; 326 return New; 327 } 328 329 // A function that has already been declared has been redeclared or defined 330 // with a different type- show appropriate diagnostic 331 diag::kind PrevDiag; 332 if (Old->isThisDeclarationADefinition()) 333 PrevDiag = diag::err_previous_definition; 334 else if (Old->isImplicit()) 335 PrevDiag = diag::err_previous_implicit_declaration; 336 else 337 PrevDiag = diag::err_previous_declaration; 338 339 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 340 // TODO: This is totally simplistic. It should handle merging functions 341 // together etc, merging extern int X; int X; ... 342 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 343 Diag(Old->getLocation(), PrevDiag); 344 return New; 345} 346 347/// equivalentArrayTypes - Used to determine whether two array types are 348/// equivalent. 349/// We need to check this explicitly as an incomplete array definition is 350/// considered a VariableArrayType, so will not match a complete array 351/// definition that would be otherwise equivalent. 352static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 353 const ArrayType *NewAT = NewQType->getAsArrayType(); 354 const ArrayType *OldAT = OldQType->getAsArrayType(); 355 356 if (!NewAT || !OldAT) 357 return false; 358 359 // If either (or both) array types in incomplete we need to strip off the 360 // outer VariableArrayType. Once the outer VAT is removed the remaining 361 // types must be identical if the array types are to be considered 362 // equivalent. 363 // eg. int[][1] and int[1][1] become 364 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 365 // removing the outermost VAT gives 366 // CAT(1, int) and CAT(1, int) 367 // which are equal, therefore the array types are equivalent. 368 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 369 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 370 return false; 371 NewQType = NewAT->getElementType().getCanonicalType(); 372 OldQType = OldAT->getElementType().getCanonicalType(); 373 } 374 375 return NewQType == OldQType; 376} 377 378/// MergeVarDecl - We just parsed a variable 'New' which has the same name 379/// and scope as a previous declaration 'Old'. Figure out how to resolve this 380/// situation, merging decls or emitting diagnostics as appropriate. 381/// 382/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 383/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 384/// 385VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 386 // Verify the old decl was also a variable. 387 VarDecl *Old = dyn_cast<VarDecl>(OldD); 388 if (!Old) { 389 Diag(New->getLocation(), diag::err_redefinition_different_kind, 390 New->getName()); 391 Diag(OldD->getLocation(), diag::err_previous_definition); 392 return New; 393 } 394 395 MergeAttributes(New, Old); 396 397 // Verify the types match. 398 QualType OldCType = Context.getCanonicalType(Old->getType()); 399 QualType NewCType = Context.getCanonicalType(New->getType()); 400 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 401 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 402 Diag(Old->getLocation(), diag::err_previous_definition); 403 return New; 404 } 405 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 406 if (New->getStorageClass() == VarDecl::Static && 407 (Old->getStorageClass() == VarDecl::None || 408 Old->getStorageClass() == VarDecl::Extern)) { 409 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 410 Diag(Old->getLocation(), diag::err_previous_definition); 411 return New; 412 } 413 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 414 if (New->getStorageClass() != VarDecl::Static && 415 Old->getStorageClass() == VarDecl::Static) { 416 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 417 Diag(Old->getLocation(), diag::err_previous_definition); 418 return New; 419 } 420 // We've verified the types match, now handle "tentative" definitions. 421 if (Old->isFileVarDecl() && New->isFileVarDecl()) { 422 // Handle C "tentative" external object definitions (C99 6.9.2). 423 bool OldIsTentative = false; 424 bool NewIsTentative = false; 425 426 if (!Old->getInit() && 427 (Old->getStorageClass() == VarDecl::None || 428 Old->getStorageClass() == VarDecl::Static)) 429 OldIsTentative = true; 430 431 // FIXME: this check doesn't work (since the initializer hasn't been 432 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 433 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 434 // thrown out the old decl. 435 if (!New->getInit() && 436 (New->getStorageClass() == VarDecl::None || 437 New->getStorageClass() == VarDecl::Static)) 438 ; // change to NewIsTentative = true; once the code is moved. 439 440 if (NewIsTentative || OldIsTentative) 441 return New; 442 } 443 // Handle __private_extern__ just like extern. 444 if (Old->getStorageClass() != VarDecl::Extern && 445 Old->getStorageClass() != VarDecl::PrivateExtern && 446 New->getStorageClass() != VarDecl::Extern && 447 New->getStorageClass() != VarDecl::PrivateExtern) { 448 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 449 Diag(Old->getLocation(), diag::err_previous_definition); 450 } 451 return New; 452} 453 454/// CheckParmsForFunctionDef - Check that the parameters of the given 455/// function are appropriate for the definition of a function. This 456/// takes care of any checks that cannot be performed on the 457/// declaration itself, e.g., that the types of each of the function 458/// parameters are complete. 459bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 460 bool HasInvalidParm = false; 461 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 462 ParmVarDecl *Param = FD->getParamDecl(p); 463 464 // C99 6.7.5.3p4: the parameters in a parameter type list in a 465 // function declarator that is part of a function definition of 466 // that function shall not have incomplete type. 467 if (Param->getType()->isIncompleteType() && 468 !Param->isInvalidDecl()) { 469 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 470 Param->getType().getAsString()); 471 Param->setInvalidDecl(); 472 HasInvalidParm = true; 473 } 474 } 475 476 return HasInvalidParm; 477} 478 479/// CreateImplicitParameter - Creates an implicit function parameter 480/// in the scope S and with the given type. This routine is used, for 481/// example, to create the implicit "self" parameter in an Objective-C 482/// method. 483ImplicitParamDecl * 484Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 485 SourceLocation IdLoc, QualType Type) { 486 ImplicitParamDecl *New = ImplicitParamDecl::Create(Context, CurContext, 487 IdLoc, Id, Type, 0); 488 if (Id) 489 PushOnScopeChains(New, S); 490 491 return New; 492} 493 494/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 495/// no declarator (e.g. "struct foo;") is parsed. 496Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 497 // TODO: emit error on 'int;' or 'const enum foo;'. 498 // TODO: emit error on 'typedef int;' 499 // if (!DS.isMissingDeclaratorOk()) Diag(...); 500 501 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 502} 503 504bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 505 // Get the type before calling CheckSingleAssignmentConstraints(), since 506 // it can promote the expression. 507 QualType InitType = Init->getType(); 508 509 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 510 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 511 InitType, Init, "initializing"); 512} 513 514bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 515 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 516 // C99 6.7.8p14. We have an array of character type with unknown size 517 // being initialized to a string literal. 518 llvm::APSInt ConstVal(32); 519 ConstVal = strLiteral->getByteLength() + 1; 520 // Return a new array type (C99 6.7.8p22). 521 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 522 ArrayType::Normal, 0); 523 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 524 // C99 6.7.8p14. We have an array of character type with known size. 525 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 526 Diag(strLiteral->getSourceRange().getBegin(), 527 diag::warn_initializer_string_for_char_array_too_long, 528 strLiteral->getSourceRange()); 529 } else { 530 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 531 } 532 // Set type from "char *" to "constant array of char". 533 strLiteral->setType(DeclT); 534 // For now, we always return false (meaning success). 535 return false; 536} 537 538StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 539 const ArrayType *AT = DeclType->getAsArrayType(); 540 if (AT && AT->getElementType()->isCharType()) { 541 return dyn_cast<StringLiteral>(Init); 542 } 543 return 0; 544} 545 546bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 547 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 548 // of unknown size ("[]") or an object type that is not a variable array type. 549 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 550 return Diag(VAT->getSizeExpr()->getLocStart(), 551 diag::err_variable_object_no_init, 552 VAT->getSizeExpr()->getSourceRange()); 553 554 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 555 if (!InitList) { 556 // FIXME: Handle wide strings 557 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 558 return CheckStringLiteralInit(strLiteral, DeclType); 559 560 if (DeclType->isArrayType()) 561 return Diag(Init->getLocStart(), 562 diag::err_array_init_list_required, 563 Init->getSourceRange()); 564 565 return CheckSingleInitializer(Init, DeclType); 566 } 567 568 InitListChecker CheckInitList(this, InitList, DeclType); 569 return CheckInitList.HadError(); 570} 571 572Sema::DeclTy * 573Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 574 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 575 IdentifierInfo *II = D.getIdentifier(); 576 577 // All of these full declarators require an identifier. If it doesn't have 578 // one, the ParsedFreeStandingDeclSpec action should be used. 579 if (II == 0) { 580 Diag(D.getDeclSpec().getSourceRange().getBegin(), 581 diag::err_declarator_need_ident, 582 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 583 return 0; 584 } 585 586 // The scope passed in may not be a decl scope. Zip up the scope tree until 587 // we find one that is. 588 while ((S->getFlags() & Scope::DeclScope) == 0) 589 S = S->getParent(); 590 591 // See if this is a redefinition of a variable in the same scope. 592 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 593 ScopedDecl *New; 594 bool InvalidDecl = false; 595 596 // In C++, the previous declaration we find might be a tag type 597 // (class or enum). In this case, the new declaration will hide the 598 // tag type. 599 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 600 PrevDecl = 0; 601 602 QualType R = GetTypeForDeclarator(D, S); 603 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 604 605 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 606 // Check that there are no default arguments (C++ only). 607 if (getLangOptions().CPlusPlus) 608 CheckExtraCXXDefaultArguments(D); 609 610 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 611 if (!NewTD) return 0; 612 613 // Handle attributes prior to checking for duplicates in MergeVarDecl 614 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 615 D.getAttributes()); 616 // Merge the decl with the existing one if appropriate. If the decl is 617 // in an outer scope, it isn't the same thing. 618 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 619 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 620 if (NewTD == 0) return 0; 621 } 622 New = NewTD; 623 if (S->getFnParent() == 0) { 624 // C99 6.7.7p2: If a typedef name specifies a variably modified type 625 // then it shall have block scope. 626 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 627 // FIXME: Diagnostic needs to be fixed. 628 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 629 InvalidDecl = true; 630 } 631 } 632 } else if (R.getTypePtr()->isFunctionType()) { 633 FunctionDecl::StorageClass SC = FunctionDecl::None; 634 switch (D.getDeclSpec().getStorageClassSpec()) { 635 default: assert(0 && "Unknown storage class!"); 636 case DeclSpec::SCS_auto: 637 case DeclSpec::SCS_register: 638 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 639 R.getAsString()); 640 InvalidDecl = true; 641 break; 642 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 643 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 644 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 645 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 646 } 647 648 bool isInline = D.getDeclSpec().isInlineSpecified(); 649 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 650 D.getIdentifierLoc(), 651 II, R, SC, isInline, 652 LastDeclarator); 653 // Handle attributes. 654 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 655 D.getAttributes()); 656 657 // Copy the parameter declarations from the declarator D to 658 // the function declaration NewFD, if they are available. 659 if (D.getNumTypeObjects() > 0 && 660 D.getTypeObject(0).Fun.hasPrototype) { 661 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 662 663 // Create Decl objects for each parameter, adding them to the 664 // FunctionDecl. 665 llvm::SmallVector<ParmVarDecl*, 16> Params; 666 667 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 668 // function that takes no arguments, not a function that takes a 669 // single void argument. 670 // We let through "const void" here because Sema::GetTypeForDeclarator 671 // already checks for that case. 672 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 673 FTI.ArgInfo[0].Param && 674 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 675 // empty arg list, don't push any params. 676 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 677 678 // In C++, the empty parameter-type-list must be spelled "void"; a 679 // typedef of void is not permitted. 680 if (getLangOptions().CPlusPlus && 681 Param->getType().getUnqualifiedType() != Context.VoidTy) { 682 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 683 } 684 685 } else { 686 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 687 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 688 } 689 690 NewFD->setParams(&Params[0], Params.size()); 691 } 692 693 // Merge the decl with the existing one if appropriate. Since C functions 694 // are in a flat namespace, make sure we consider decls in outer scopes. 695 if (PrevDecl && 696 (!getLangOptions().CPlusPlus || 697 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { 698 bool Redeclaration = false; 699 NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); 700 if (NewFD == 0) return 0; 701 if (Redeclaration) { 702 NewFD->setPreviousDeclaration(cast<FunctionDecl>(PrevDecl)); 703 } 704 } 705 New = NewFD; 706 707 // In C++, check default arguments now that we have merged decls. 708 if (getLangOptions().CPlusPlus) 709 CheckCXXDefaultArguments(NewFD); 710 } else { 711 // Check that there are no default arguments (C++ only). 712 if (getLangOptions().CPlusPlus) 713 CheckExtraCXXDefaultArguments(D); 714 715 if (R.getTypePtr()->isObjCInterfaceType()) { 716 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 717 D.getIdentifier()->getName()); 718 InvalidDecl = true; 719 } 720 721 VarDecl *NewVD; 722 VarDecl::StorageClass SC; 723 switch (D.getDeclSpec().getStorageClassSpec()) { 724 default: assert(0 && "Unknown storage class!"); 725 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 726 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 727 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 728 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 729 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 730 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 731 } 732 if (S->getFnParent() == 0) { 733 // C99 6.9p2: The storage-class specifiers auto and register shall not 734 // appear in the declaration specifiers in an external declaration. 735 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 736 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 737 R.getAsString()); 738 InvalidDecl = true; 739 } 740 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 741 II, R, SC, LastDeclarator); 742 } else { 743 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 744 II, R, SC, LastDeclarator); 745 } 746 // Handle attributes prior to checking for duplicates in MergeVarDecl 747 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 748 D.getAttributes()); 749 750 // Emit an error if an address space was applied to decl with local storage. 751 // This includes arrays of objects with address space qualifiers, but not 752 // automatic variables that point to other address spaces. 753 // ISO/IEC TR 18037 S5.1.2 754 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 755 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 756 InvalidDecl = true; 757 } 758 // Merge the decl with the existing one if appropriate. If the decl is 759 // in an outer scope, it isn't the same thing. 760 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 761 NewVD = MergeVarDecl(NewVD, PrevDecl); 762 if (NewVD == 0) return 0; 763 } 764 New = NewVD; 765 } 766 767 // If this has an identifier, add it to the scope stack. 768 if (II) 769 PushOnScopeChains(New, S); 770 // If any semantic error occurred, mark the decl as invalid. 771 if (D.getInvalidType() || InvalidDecl) 772 New->setInvalidDecl(); 773 774 return New; 775} 776 777bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 778 switch (Init->getStmtClass()) { 779 default: 780 Diag(Init->getExprLoc(), 781 diag::err_init_element_not_constant, Init->getSourceRange()); 782 return true; 783 case Expr::ParenExprClass: { 784 const ParenExpr* PE = cast<ParenExpr>(Init); 785 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 786 } 787 case Expr::CompoundLiteralExprClass: 788 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 789 case Expr::DeclRefExprClass: { 790 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 791 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 792 if (VD->hasGlobalStorage()) 793 return false; 794 Diag(Init->getExprLoc(), 795 diag::err_init_element_not_constant, Init->getSourceRange()); 796 return true; 797 } 798 if (isa<FunctionDecl>(D)) 799 return false; 800 Diag(Init->getExprLoc(), 801 diag::err_init_element_not_constant, Init->getSourceRange()); 802 return true; 803 } 804 case Expr::MemberExprClass: { 805 const MemberExpr *M = cast<MemberExpr>(Init); 806 if (M->isArrow()) 807 return CheckAddressConstantExpression(M->getBase()); 808 return CheckAddressConstantExpressionLValue(M->getBase()); 809 } 810 case Expr::ArraySubscriptExprClass: { 811 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 812 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 813 return CheckAddressConstantExpression(ASE->getBase()) || 814 CheckArithmeticConstantExpression(ASE->getIdx()); 815 } 816 case Expr::StringLiteralClass: 817 case Expr::PreDefinedExprClass: 818 return false; 819 case Expr::UnaryOperatorClass: { 820 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 821 822 // C99 6.6p9 823 if (Exp->getOpcode() == UnaryOperator::Deref) 824 return CheckAddressConstantExpression(Exp->getSubExpr()); 825 826 Diag(Init->getExprLoc(), 827 diag::err_init_element_not_constant, Init->getSourceRange()); 828 return true; 829 } 830 } 831} 832 833bool Sema::CheckAddressConstantExpression(const Expr* Init) { 834 switch (Init->getStmtClass()) { 835 default: 836 Diag(Init->getExprLoc(), 837 diag::err_init_element_not_constant, Init->getSourceRange()); 838 return true; 839 case Expr::ParenExprClass: { 840 const ParenExpr* PE = cast<ParenExpr>(Init); 841 return CheckAddressConstantExpression(PE->getSubExpr()); 842 } 843 case Expr::StringLiteralClass: 844 case Expr::ObjCStringLiteralClass: 845 return false; 846 case Expr::CallExprClass: { 847 const CallExpr *CE = cast<CallExpr>(Init); 848 if (CE->isBuiltinConstantExpr()) 849 return false; 850 Diag(Init->getExprLoc(), 851 diag::err_init_element_not_constant, Init->getSourceRange()); 852 return true; 853 } 854 case Expr::UnaryOperatorClass: { 855 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 856 857 // C99 6.6p9 858 if (Exp->getOpcode() == UnaryOperator::AddrOf) 859 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 860 861 if (Exp->getOpcode() == UnaryOperator::Extension) 862 return CheckAddressConstantExpression(Exp->getSubExpr()); 863 864 Diag(Init->getExprLoc(), 865 diag::err_init_element_not_constant, Init->getSourceRange()); 866 return true; 867 } 868 case Expr::BinaryOperatorClass: { 869 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 870 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 871 872 Expr *PExp = Exp->getLHS(); 873 Expr *IExp = Exp->getRHS(); 874 if (IExp->getType()->isPointerType()) 875 std::swap(PExp, IExp); 876 877 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 878 return CheckAddressConstantExpression(PExp) || 879 CheckArithmeticConstantExpression(IExp); 880 } 881 case Expr::ImplicitCastExprClass: { 882 const Expr* SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 883 884 // Check for implicit promotion 885 if (SubExpr->getType()->isFunctionType() || 886 SubExpr->getType()->isArrayType()) 887 return CheckAddressConstantExpressionLValue(SubExpr); 888 889 // Check for pointer->pointer cast 890 if (SubExpr->getType()->isPointerType()) 891 return CheckAddressConstantExpression(SubExpr); 892 893 if (SubExpr->getType()->isArithmeticType()) 894 return CheckArithmeticConstantExpression(SubExpr); 895 896 Diag(Init->getExprLoc(), 897 diag::err_init_element_not_constant, Init->getSourceRange()); 898 return true; 899 } 900 case Expr::CastExprClass: { 901 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 902 903 // Check for pointer->pointer cast 904 if (SubExpr->getType()->isPointerType()) 905 return CheckAddressConstantExpression(SubExpr); 906 907 // FIXME: Should we pedwarn for (int*)(0+0)? 908 if (SubExpr->getType()->isArithmeticType()) 909 return CheckArithmeticConstantExpression(SubExpr); 910 911 Diag(Init->getExprLoc(), 912 diag::err_init_element_not_constant, Init->getSourceRange()); 913 return true; 914 } 915 case Expr::ConditionalOperatorClass: { 916 // FIXME: Should we pedwarn here? 917 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 918 if (!Exp->getCond()->getType()->isArithmeticType()) { 919 Diag(Init->getExprLoc(), 920 diag::err_init_element_not_constant, Init->getSourceRange()); 921 return true; 922 } 923 if (CheckArithmeticConstantExpression(Exp->getCond())) 924 return true; 925 if (Exp->getLHS() && 926 CheckAddressConstantExpression(Exp->getLHS())) 927 return true; 928 return CheckAddressConstantExpression(Exp->getRHS()); 929 } 930 case Expr::AddrLabelExprClass: 931 return false; 932 } 933} 934 935static const Expr* FindExpressionBaseAddress(const Expr* E); 936 937static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 938 switch (E->getStmtClass()) { 939 default: 940 return E; 941 case Expr::ParenExprClass: { 942 const ParenExpr* PE = cast<ParenExpr>(E); 943 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 944 } 945 case Expr::MemberExprClass: { 946 const MemberExpr *M = cast<MemberExpr>(E); 947 if (M->isArrow()) 948 return FindExpressionBaseAddress(M->getBase()); 949 return FindExpressionBaseAddressLValue(M->getBase()); 950 } 951 case Expr::ArraySubscriptExprClass: { 952 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 953 return FindExpressionBaseAddress(ASE->getBase()); 954 } 955 case Expr::UnaryOperatorClass: { 956 const UnaryOperator *Exp = cast<UnaryOperator>(E); 957 958 if (Exp->getOpcode() == UnaryOperator::Deref) 959 return FindExpressionBaseAddress(Exp->getSubExpr()); 960 961 return E; 962 } 963 } 964} 965 966static const Expr* FindExpressionBaseAddress(const Expr* E) { 967 switch (E->getStmtClass()) { 968 default: 969 return E; 970 case Expr::ParenExprClass: { 971 const ParenExpr* PE = cast<ParenExpr>(E); 972 return FindExpressionBaseAddress(PE->getSubExpr()); 973 } 974 case Expr::UnaryOperatorClass: { 975 const UnaryOperator *Exp = cast<UnaryOperator>(E); 976 977 // C99 6.6p9 978 if (Exp->getOpcode() == UnaryOperator::AddrOf) 979 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 980 981 if (Exp->getOpcode() == UnaryOperator::Extension) 982 return FindExpressionBaseAddress(Exp->getSubExpr()); 983 984 return E; 985 } 986 case Expr::BinaryOperatorClass: { 987 const BinaryOperator *Exp = cast<BinaryOperator>(E); 988 989 Expr *PExp = Exp->getLHS(); 990 Expr *IExp = Exp->getRHS(); 991 if (IExp->getType()->isPointerType()) 992 std::swap(PExp, IExp); 993 994 return FindExpressionBaseAddress(PExp); 995 } 996 case Expr::ImplicitCastExprClass: { 997 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 998 999 // Check for implicit promotion 1000 if (SubExpr->getType()->isFunctionType() || 1001 SubExpr->getType()->isArrayType()) 1002 return FindExpressionBaseAddressLValue(SubExpr); 1003 1004 // Check for pointer->pointer cast 1005 if (SubExpr->getType()->isPointerType()) 1006 return FindExpressionBaseAddress(SubExpr); 1007 1008 // We assume that we have an arithmetic expression here; 1009 // if we don't, we'll figure it out later 1010 return 0; 1011 } 1012 case Expr::CastExprClass: { 1013 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1014 1015 // Check for pointer->pointer cast 1016 if (SubExpr->getType()->isPointerType()) 1017 return FindExpressionBaseAddress(SubExpr); 1018 1019 // We assume that we have an arithmetic expression here; 1020 // if we don't, we'll figure it out later 1021 return 0; 1022 } 1023 } 1024} 1025 1026bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1027 switch (Init->getStmtClass()) { 1028 default: 1029 Diag(Init->getExprLoc(), 1030 diag::err_init_element_not_constant, Init->getSourceRange()); 1031 return true; 1032 case Expr::ParenExprClass: { 1033 const ParenExpr* PE = cast<ParenExpr>(Init); 1034 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1035 } 1036 case Expr::FloatingLiteralClass: 1037 case Expr::IntegerLiteralClass: 1038 case Expr::CharacterLiteralClass: 1039 case Expr::ImaginaryLiteralClass: 1040 case Expr::TypesCompatibleExprClass: 1041 case Expr::CXXBoolLiteralExprClass: 1042 return false; 1043 case Expr::CallExprClass: { 1044 const CallExpr *CE = cast<CallExpr>(Init); 1045 if (CE->isBuiltinConstantExpr()) 1046 return false; 1047 Diag(Init->getExprLoc(), 1048 diag::err_init_element_not_constant, Init->getSourceRange()); 1049 return true; 1050 } 1051 case Expr::DeclRefExprClass: { 1052 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1053 if (isa<EnumConstantDecl>(D)) 1054 return false; 1055 Diag(Init->getExprLoc(), 1056 diag::err_init_element_not_constant, Init->getSourceRange()); 1057 return true; 1058 } 1059 case Expr::CompoundLiteralExprClass: 1060 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1061 // but vectors are allowed to be magic. 1062 if (Init->getType()->isVectorType()) 1063 return false; 1064 Diag(Init->getExprLoc(), 1065 diag::err_init_element_not_constant, Init->getSourceRange()); 1066 return true; 1067 case Expr::UnaryOperatorClass: { 1068 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1069 1070 switch (Exp->getOpcode()) { 1071 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1072 // See C99 6.6p3. 1073 default: 1074 Diag(Init->getExprLoc(), 1075 diag::err_init_element_not_constant, Init->getSourceRange()); 1076 return true; 1077 case UnaryOperator::SizeOf: 1078 case UnaryOperator::AlignOf: 1079 case UnaryOperator::OffsetOf: 1080 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1081 // See C99 6.5.3.4p2 and 6.6p3. 1082 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1083 return false; 1084 Diag(Init->getExprLoc(), 1085 diag::err_init_element_not_constant, Init->getSourceRange()); 1086 return true; 1087 case UnaryOperator::Extension: 1088 case UnaryOperator::LNot: 1089 case UnaryOperator::Plus: 1090 case UnaryOperator::Minus: 1091 case UnaryOperator::Not: 1092 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1093 } 1094 } 1095 case Expr::SizeOfAlignOfTypeExprClass: { 1096 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1097 // Special check for void types, which are allowed as an extension 1098 if (Exp->getArgumentType()->isVoidType()) 1099 return false; 1100 // alignof always evaluates to a constant. 1101 // FIXME: is sizeof(int[3.0]) a constant expression? 1102 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1103 Diag(Init->getExprLoc(), 1104 diag::err_init_element_not_constant, Init->getSourceRange()); 1105 return true; 1106 } 1107 return false; 1108 } 1109 case Expr::BinaryOperatorClass: { 1110 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1111 1112 if (Exp->getLHS()->getType()->isArithmeticType() && 1113 Exp->getRHS()->getType()->isArithmeticType()) { 1114 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1115 CheckArithmeticConstantExpression(Exp->getRHS()); 1116 } 1117 1118 if (Exp->getLHS()->getType()->isPointerType() && 1119 Exp->getRHS()->getType()->isPointerType()) { 1120 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1121 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1122 1123 // Only allow a null (constant integer) base; we could 1124 // allow some additional cases if necessary, but this 1125 // is sufficient to cover offsetof-like constructs. 1126 if (!LHSBase && !RHSBase) { 1127 return CheckAddressConstantExpression(Exp->getLHS()) || 1128 CheckAddressConstantExpression(Exp->getRHS()); 1129 } 1130 } 1131 1132 Diag(Init->getExprLoc(), 1133 diag::err_init_element_not_constant, Init->getSourceRange()); 1134 return true; 1135 } 1136 case Expr::ImplicitCastExprClass: 1137 case Expr::CastExprClass: { 1138 const Expr *SubExpr; 1139 if (const CastExpr *C = dyn_cast<CastExpr>(Init)) { 1140 SubExpr = C->getSubExpr(); 1141 } else { 1142 SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1143 } 1144 1145 if (SubExpr->getType()->isArithmeticType()) 1146 return CheckArithmeticConstantExpression(SubExpr); 1147 1148 Diag(Init->getExprLoc(), 1149 diag::err_init_element_not_constant, Init->getSourceRange()); 1150 return true; 1151 } 1152 case Expr::ConditionalOperatorClass: { 1153 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1154 if (CheckArithmeticConstantExpression(Exp->getCond())) 1155 return true; 1156 if (Exp->getLHS() && 1157 CheckArithmeticConstantExpression(Exp->getLHS())) 1158 return true; 1159 return CheckArithmeticConstantExpression(Exp->getRHS()); 1160 } 1161 } 1162} 1163 1164bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1165 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1166 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1167 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1168 1169 if (Init->getType()->isReferenceType()) { 1170 // FIXME: Work out how the heck reference types work 1171 return false; 1172#if 0 1173 // A reference is constant if the address of the expression 1174 // is constant 1175 // We look through initlists here to simplify 1176 // CheckAddressConstantExpressionLValue. 1177 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1178 assert(Exp->getNumInits() > 0 && 1179 "Refernce initializer cannot be empty"); 1180 Init = Exp->getInit(0); 1181 } 1182 return CheckAddressConstantExpressionLValue(Init); 1183#endif 1184 } 1185 1186 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1187 unsigned numInits = Exp->getNumInits(); 1188 for (unsigned i = 0; i < numInits; i++) { 1189 // FIXME: Need to get the type of the declaration for C++, 1190 // because it could be a reference? 1191 if (CheckForConstantInitializer(Exp->getInit(i), 1192 Exp->getInit(i)->getType())) 1193 return true; 1194 } 1195 return false; 1196 } 1197 1198 if (Init->isNullPointerConstant(Context)) 1199 return false; 1200 if (Init->getType()->isArithmeticType()) { 1201 QualType InitTy = Init->getType().getCanonicalType().getUnqualifiedType(); 1202 if (InitTy == Context.BoolTy) { 1203 // Special handling for pointers implicitly cast to bool; 1204 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1205 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1206 Expr* SubE = ICE->getSubExpr(); 1207 if (SubE->getType()->isPointerType() || 1208 SubE->getType()->isArrayType() || 1209 SubE->getType()->isFunctionType()) { 1210 return CheckAddressConstantExpression(Init); 1211 } 1212 } 1213 } else if (InitTy->isIntegralType()) { 1214 Expr* SubE = 0; 1215 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) 1216 SubE = ICE->getSubExpr(); 1217 else if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1218 SubE = CE->getSubExpr(); 1219 // Special check for pointer cast to int; we allow as an extension 1220 // an address constant cast to an integer if the integer 1221 // is of an appropriate width (this sort of code is apparently used 1222 // in some places). 1223 // FIXME: Add pedwarn? 1224 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1225 if (SubE && (SubE->getType()->isPointerType() || 1226 SubE->getType()->isArrayType() || 1227 SubE->getType()->isFunctionType())) { 1228 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1229 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1230 if (IntWidth >= PointerWidth) 1231 return CheckAddressConstantExpression(Init); 1232 } 1233 } 1234 1235 return CheckArithmeticConstantExpression(Init); 1236 } 1237 1238 if (Init->getType()->isPointerType()) 1239 return CheckAddressConstantExpression(Init); 1240 1241 // An array type at the top level that isn't an init-list must 1242 // be a string literal 1243 if (Init->getType()->isArrayType()) 1244 return false; 1245 1246 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1247 Init->getSourceRange()); 1248 return true; 1249} 1250 1251void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1252 Decl *RealDecl = static_cast<Decl *>(dcl); 1253 Expr *Init = static_cast<Expr *>(init); 1254 assert(Init && "missing initializer"); 1255 1256 // If there is no declaration, there was an error parsing it. Just ignore 1257 // the initializer. 1258 if (RealDecl == 0) { 1259 delete Init; 1260 return; 1261 } 1262 1263 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1264 if (!VDecl) { 1265 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1266 diag::err_illegal_initializer); 1267 RealDecl->setInvalidDecl(); 1268 return; 1269 } 1270 // Get the decls type and save a reference for later, since 1271 // CheckInitializerTypes may change it. 1272 QualType DclT = VDecl->getType(), SavT = DclT; 1273 if (VDecl->isBlockVarDecl()) { 1274 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1275 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1276 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1277 VDecl->setInvalidDecl(); 1278 } else if (!VDecl->isInvalidDecl()) { 1279 if (CheckInitializerTypes(Init, DclT)) 1280 VDecl->setInvalidDecl(); 1281 if (SC == VarDecl::Static) // C99 6.7.8p4. 1282 CheckForConstantInitializer(Init, DclT); 1283 } 1284 } else if (VDecl->isFileVarDecl()) { 1285 if (VDecl->getStorageClass() == VarDecl::Extern) 1286 Diag(VDecl->getLocation(), diag::warn_extern_init); 1287 if (!VDecl->isInvalidDecl()) 1288 if (CheckInitializerTypes(Init, DclT)) 1289 VDecl->setInvalidDecl(); 1290 1291 // C99 6.7.8p4. All file scoped initializers need to be constant. 1292 CheckForConstantInitializer(Init, DclT); 1293 } 1294 // If the type changed, it means we had an incomplete type that was 1295 // completed by the initializer. For example: 1296 // int ary[] = { 1, 3, 5 }; 1297 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1298 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1299 VDecl->setType(DclT); 1300 Init->setType(DclT); 1301 } 1302 1303 // Attach the initializer to the decl. 1304 VDecl->setInit(Init); 1305 return; 1306} 1307 1308/// The declarators are chained together backwards, reverse the list. 1309Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1310 // Often we have single declarators, handle them quickly. 1311 Decl *GroupDecl = static_cast<Decl*>(group); 1312 if (GroupDecl == 0) 1313 return 0; 1314 1315 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1316 ScopedDecl *NewGroup = 0; 1317 if (Group->getNextDeclarator() == 0) 1318 NewGroup = Group; 1319 else { // reverse the list. 1320 while (Group) { 1321 ScopedDecl *Next = Group->getNextDeclarator(); 1322 Group->setNextDeclarator(NewGroup); 1323 NewGroup = Group; 1324 Group = Next; 1325 } 1326 } 1327 // Perform semantic analysis that depends on having fully processed both 1328 // the declarator and initializer. 1329 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1330 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1331 if (!IDecl) 1332 continue; 1333 QualType T = IDecl->getType(); 1334 1335 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1336 // static storage duration, it shall not have a variable length array. 1337 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1338 IDecl->getStorageClass() == VarDecl::Static) { 1339 if (T->getAsVariableArrayType()) { 1340 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1341 IDecl->setInvalidDecl(); 1342 } 1343 } 1344 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1345 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1346 if (IDecl->isBlockVarDecl() && 1347 IDecl->getStorageClass() != VarDecl::Extern) { 1348 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1349 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1350 T.getAsString()); 1351 IDecl->setInvalidDecl(); 1352 } 1353 } 1354 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1355 // object that has file scope without an initializer, and without a 1356 // storage-class specifier or with the storage-class specifier "static", 1357 // constitutes a tentative definition. Note: A tentative definition with 1358 // external linkage is valid (C99 6.2.2p5). 1359 if (IDecl && !IDecl->getInit() && 1360 (IDecl->getStorageClass() == VarDecl::Static || 1361 IDecl->getStorageClass() == VarDecl::None)) { 1362 if (T->isIncompleteArrayType()) { 1363 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1364 // array to be completed. Don't issue a diagnostic. 1365 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1366 // C99 6.9.2p3: If the declaration of an identifier for an object is 1367 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1368 // declared type shall not be an incomplete type. 1369 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1370 T.getAsString()); 1371 IDecl->setInvalidDecl(); 1372 } 1373 } 1374 } 1375 return NewGroup; 1376} 1377 1378/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1379/// to introduce parameters into function prototype scope. 1380Sema::DeclTy * 1381Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1382 DeclSpec &DS = D.getDeclSpec(); 1383 1384 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1385 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1386 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1387 Diag(DS.getStorageClassSpecLoc(), 1388 diag::err_invalid_storage_class_in_func_decl); 1389 DS.ClearStorageClassSpecs(); 1390 } 1391 if (DS.isThreadSpecified()) { 1392 Diag(DS.getThreadSpecLoc(), 1393 diag::err_invalid_storage_class_in_func_decl); 1394 DS.ClearStorageClassSpecs(); 1395 } 1396 1397 // Check that there are no default arguments inside the type of this 1398 // parameter (C++ only). 1399 if (getLangOptions().CPlusPlus) 1400 CheckExtraCXXDefaultArguments(D); 1401 1402 // In this context, we *do not* check D.getInvalidType(). If the declarator 1403 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1404 // though it will not reflect the user specified type. 1405 QualType parmDeclType = GetTypeForDeclarator(D, S); 1406 1407 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1408 1409 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1410 // Can this happen for params? We already checked that they don't conflict 1411 // among each other. Here they can only shadow globals, which is ok. 1412 IdentifierInfo *II = D.getIdentifier(); 1413 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1414 if (S->isDeclScope(PrevDecl)) { 1415 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1416 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1417 1418 // Recover by removing the name 1419 II = 0; 1420 D.SetIdentifier(0, D.getIdentifierLoc()); 1421 } 1422 } 1423 1424 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1425 // Doing the promotion here has a win and a loss. The win is the type for 1426 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1427 // code generator). The loss is the orginal type isn't preserved. For example: 1428 // 1429 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1430 // int blockvardecl[5]; 1431 // sizeof(parmvardecl); // size == 4 1432 // sizeof(blockvardecl); // size == 20 1433 // } 1434 // 1435 // For expressions, all implicit conversions are captured using the 1436 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1437 // 1438 // FIXME: If a source translation tool needs to see the original type, then 1439 // we need to consider storing both types (in ParmVarDecl)... 1440 // 1441 if (parmDeclType->isArrayType()) { 1442 // int x[restrict 4] -> int *restrict 1443 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1444 } else if (parmDeclType->isFunctionType()) 1445 parmDeclType = Context.getPointerType(parmDeclType); 1446 1447 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1448 D.getIdentifierLoc(), II, 1449 parmDeclType, VarDecl::None, 1450 0, 0); 1451 1452 if (D.getInvalidType()) 1453 New->setInvalidDecl(); 1454 1455 if (II) 1456 PushOnScopeChains(New, S); 1457 1458 HandleDeclAttributes(New, D.getDeclSpec().getAttributes(), 1459 D.getAttributes()); 1460 return New; 1461 1462} 1463 1464Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1465 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1466 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1467 "Not a function declarator!"); 1468 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1469 1470 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1471 // for a K&R function. 1472 if (!FTI.hasPrototype) { 1473 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1474 if (FTI.ArgInfo[i].Param == 0) { 1475 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1476 FTI.ArgInfo[i].Ident->getName()); 1477 // Implicitly declare the argument as type 'int' for lack of a better 1478 // type. 1479 DeclSpec DS; 1480 const char* PrevSpec; // unused 1481 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1482 PrevSpec); 1483 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1484 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1485 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1486 } 1487 } 1488 1489 // Since this is a function definition, act as though we have information 1490 // about the arguments. 1491 if (FTI.NumArgs) 1492 FTI.hasPrototype = true; 1493 } else { 1494 // FIXME: Diagnose arguments without names in C. 1495 } 1496 1497 Scope *GlobalScope = FnBodyScope->getParent(); 1498 1499 // See if this is a redefinition. 1500 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1501 GlobalScope); 1502 if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { 1503 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1504 const FunctionDecl *Definition; 1505 if (FD->getBody(Definition)) { 1506 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1507 D.getIdentifier()->getName()); 1508 Diag(Definition->getLocation(), diag::err_previous_definition); 1509 } 1510 } 1511 } 1512 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1513 FunctionDecl *FD = cast<FunctionDecl>(decl); 1514 CurFunctionDecl = FD; 1515 PushDeclContext(FD); 1516 1517 // Check the validity of our function parameters 1518 CheckParmsForFunctionDef(FD); 1519 1520 // Introduce our parameters into the function scope 1521 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1522 ParmVarDecl *Param = FD->getParamDecl(p); 1523 // If this has an identifier, add it to the scope stack. 1524 if (Param->getIdentifier()) 1525 PushOnScopeChains(Param, FnBodyScope); 1526 } 1527 1528 return FD; 1529} 1530 1531Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1532 Decl *dcl = static_cast<Decl *>(D); 1533 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1534 FD->setBody((Stmt*)Body); 1535 assert(FD == CurFunctionDecl && "Function parsing confused"); 1536 CurFunctionDecl = 0; 1537 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1538 MD->setBody((Stmt*)Body); 1539 CurMethodDecl = 0; 1540 } 1541 PopDeclContext(); 1542 // Verify and clean out per-function state. 1543 1544 // Check goto/label use. 1545 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1546 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1547 // Verify that we have no forward references left. If so, there was a goto 1548 // or address of a label taken, but no definition of it. Label fwd 1549 // definitions are indicated with a null substmt. 1550 if (I->second->getSubStmt() == 0) { 1551 LabelStmt *L = I->second; 1552 // Emit error. 1553 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1554 1555 // At this point, we have gotos that use the bogus label. Stitch it into 1556 // the function body so that they aren't leaked and that the AST is well 1557 // formed. 1558 if (Body) { 1559 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1560 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1561 } else { 1562 // The whole function wasn't parsed correctly, just delete this. 1563 delete L; 1564 } 1565 } 1566 } 1567 LabelMap.clear(); 1568 1569 return D; 1570} 1571 1572/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1573/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1574ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1575 IdentifierInfo &II, Scope *S) { 1576 // Extension in C99. Legal in C90, but warn about it. 1577 if (getLangOptions().C99) 1578 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1579 else 1580 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1581 1582 // FIXME: handle stuff like: 1583 // void foo() { extern float X(); } 1584 // void bar() { X(); } <-- implicit decl for X in another scope. 1585 1586 // Set a Declarator for the implicit definition: int foo(); 1587 const char *Dummy; 1588 DeclSpec DS; 1589 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1590 Error = Error; // Silence warning. 1591 assert(!Error && "Error setting up implicit decl!"); 1592 Declarator D(DS, Declarator::BlockContext); 1593 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1594 D.SetIdentifier(&II, Loc); 1595 1596 // Insert this function into translation-unit scope. 1597 1598 DeclContext *PrevDC = CurContext; 1599 CurContext = Context.getTranslationUnitDecl(); 1600 1601 FunctionDecl *FD = 1602 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1603 FD->setImplicit(); 1604 1605 CurContext = PrevDC; 1606 1607 return FD; 1608} 1609 1610 1611TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1612 ScopedDecl *LastDeclarator) { 1613 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1614 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1615 1616 // Scope manipulation handled by caller. 1617 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1618 D.getIdentifierLoc(), 1619 D.getIdentifier(), 1620 T, LastDeclarator); 1621 if (D.getInvalidType()) 1622 NewTD->setInvalidDecl(); 1623 return NewTD; 1624} 1625 1626/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1627/// former case, Name will be non-null. In the later case, Name will be null. 1628/// TagType indicates what kind of tag this is. TK indicates whether this is a 1629/// reference/declaration/definition of a tag. 1630Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1631 SourceLocation KWLoc, IdentifierInfo *Name, 1632 SourceLocation NameLoc, AttributeList *Attr) { 1633 // If this is a use of an existing tag, it must have a name. 1634 assert((Name != 0 || TK == TK_Definition) && 1635 "Nameless record must be a definition!"); 1636 1637 TagDecl::TagKind Kind; 1638 switch (TagType) { 1639 default: assert(0 && "Unknown tag type!"); 1640 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 1641 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 1642 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 1643 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 1644 } 1645 1646 // If this is a named struct, check to see if there was a previous forward 1647 // declaration or definition. 1648 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1649 if (ScopedDecl *PrevDecl = 1650 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1651 1652 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1653 "unexpected Decl type"); 1654 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1655 // If this is a use of a previous tag, or if the tag is already declared in 1656 // the same scope (so that the definition/declaration completes or 1657 // rementions the tag), reuse the decl. 1658 if (TK == TK_Reference || 1659 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1660 // Make sure that this wasn't declared as an enum and now used as a struct 1661 // or something similar. 1662 if (PrevTagDecl->getTagKind() != Kind) { 1663 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1664 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1665 } 1666 1667 // If this is a use or a forward declaration, we're good. 1668 if (TK != TK_Definition) 1669 return PrevDecl; 1670 1671 // Diagnose attempts to redefine a tag. 1672 if (PrevTagDecl->isDefinition()) { 1673 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1674 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1675 // If this is a redefinition, recover by making this struct be 1676 // anonymous, which will make any later references get the previous 1677 // definition. 1678 Name = 0; 1679 } else { 1680 // Okay, this is definition of a previously declared or referenced tag. 1681 // Move the location of the decl to be the definition site. 1682 PrevDecl->setLocation(NameLoc); 1683 return PrevDecl; 1684 } 1685 } 1686 // If we get here, this is a definition of a new struct type in a nested 1687 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1688 // type. 1689 } else { 1690 // The tag name clashes with a namespace name, issue an error and recover 1691 // by making this tag be anonymous. 1692 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1693 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1694 Name = 0; 1695 } 1696 } 1697 1698 // If there is an identifier, use the location of the identifier as the 1699 // location of the decl, otherwise use the location of the struct/union 1700 // keyword. 1701 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1702 1703 // Otherwise, if this is the first time we've seen this tag, create the decl. 1704 TagDecl *New; 1705 if (Kind == TagDecl::TK_enum) { 1706 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1707 // enum X { A, B, C } D; D should chain to X. 1708 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1709 // If this is an undefined enum, warn. 1710 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1711 } else { 1712 // struct/union/class 1713 1714 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1715 // struct X { int A; } D; D should chain to X. 1716 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1717 } 1718 1719 // If this has an identifier, add it to the scope stack. 1720 if (Name) { 1721 // The scope passed in may not be a decl scope. Zip up the scope tree until 1722 // we find one that is. 1723 while ((S->getFlags() & Scope::DeclScope) == 0) 1724 S = S->getParent(); 1725 1726 // Add it to the decl chain. 1727 PushOnScopeChains(New, S); 1728 } 1729 1730 HandleDeclAttributes(New, Attr, 0); 1731 return New; 1732} 1733 1734static bool CalcFakeICEVal(const Expr* Expr, 1735 llvm::APSInt& Result, 1736 ASTContext& Context) { 1737 // Calculate the value of an expression that has a calculatable 1738 // value, but isn't an ICE. Currently, this only supports 1739 // a very narrow set of extensions, but it can be expanded if needed. 1740 if (const ParenExpr *PE = dyn_cast<ParenExpr>(Expr)) 1741 return CalcFakeICEVal(PE->getSubExpr(), Result, Context); 1742 1743 if (const CastExpr *CE = dyn_cast<CastExpr>(Expr)) { 1744 QualType CETy = CE->getType(); 1745 if ((CETy->isIntegralType() && !CETy->isBooleanType()) || 1746 CETy->isPointerType()) { 1747 if (CalcFakeICEVal(CE->getSubExpr(), Result, Context)) { 1748 Result.extOrTrunc(Context.getTypeSize(CETy)); 1749 // FIXME: This assumes pointers are signed. 1750 Result.setIsSigned(CETy->isSignedIntegerType() || 1751 CETy->isPointerType()); 1752 return true; 1753 } 1754 } 1755 } 1756 1757 if (Expr->getType()->isIntegralType()) 1758 return Expr->isIntegerConstantExpr(Result, Context); 1759 1760 return false; 1761} 1762 1763QualType Sema::TryFixInvalidVariablyModifiedType(QualType T) { 1764 // This method tries to turn a variable array into a constant 1765 // array even when the size isn't an ICE. This is necessary 1766 // for compatibility with code that depends on gcc's buggy 1767 // constant expression folding, like struct {char x[(int)(char*)2];} 1768 if (const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T)) { 1769 llvm::APSInt Result(32); 1770 if (VLATy->getSizeExpr() && 1771 CalcFakeICEVal(VLATy->getSizeExpr(), Result, Context) && 1772 Result > llvm::APSInt(Result.getBitWidth(), Result.isUnsigned())) { 1773 return Context.getConstantArrayType(VLATy->getElementType(), 1774 Result, ArrayType::Normal, 0); 1775 } 1776 } 1777 return QualType(); 1778} 1779 1780/// ActOnField - Each field of a struct/union/class is passed into this in order 1781/// to create a FieldDecl object for it. 1782Sema::DeclTy *Sema::ActOnField(Scope *S, 1783 SourceLocation DeclStart, 1784 Declarator &D, ExprTy *BitfieldWidth) { 1785 IdentifierInfo *II = D.getIdentifier(); 1786 Expr *BitWidth = (Expr*)BitfieldWidth; 1787 SourceLocation Loc = DeclStart; 1788 if (II) Loc = D.getIdentifierLoc(); 1789 1790 // FIXME: Unnamed fields can be handled in various different ways, for 1791 // example, unnamed unions inject all members into the struct namespace! 1792 1793 1794 if (BitWidth) { 1795 // TODO: Validate. 1796 //printf("WARNING: BITFIELDS IGNORED!\n"); 1797 1798 // 6.7.2.1p3 1799 // 6.7.2.1p4 1800 1801 } else { 1802 // Not a bitfield. 1803 1804 // validate II. 1805 1806 } 1807 1808 QualType T = GetTypeForDeclarator(D, S); 1809 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1810 bool InvalidDecl = false; 1811 1812 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1813 // than a variably modified type. 1814 if (T->isVariablyModifiedType()) { 1815 QualType FixedTy = TryFixInvalidVariablyModifiedType(T); 1816 if (!FixedTy.isNull()) { 1817 Diag(Loc, diag::warn_illegal_constant_array_size, Loc); 1818 T = FixedTy; 1819 } else { 1820 // FIXME: This diagnostic needs work 1821 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1822 InvalidDecl = true; 1823 } 1824 } 1825 // FIXME: Chain fielddecls together. 1826 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1827 1828 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1829 D.getAttributes()); 1830 1831 if (D.getInvalidType() || InvalidDecl) 1832 NewFD->setInvalidDecl(); 1833 return NewFD; 1834} 1835 1836/// TranslateIvarVisibility - Translate visibility from a token ID to an 1837/// AST enum value. 1838static ObjCIvarDecl::AccessControl 1839TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1840 switch (ivarVisibility) { 1841 case tok::objc_private: return ObjCIvarDecl::Private; 1842 case tok::objc_public: return ObjCIvarDecl::Public; 1843 case tok::objc_protected: return ObjCIvarDecl::Protected; 1844 case tok::objc_package: return ObjCIvarDecl::Package; 1845 default: assert(false && "Unknown visitibility kind"); 1846 } 1847} 1848 1849/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1850/// in order to create an IvarDecl object for it. 1851Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1852 SourceLocation DeclStart, 1853 Declarator &D, ExprTy *BitfieldWidth, 1854 tok::ObjCKeywordKind Visibility) { 1855 IdentifierInfo *II = D.getIdentifier(); 1856 Expr *BitWidth = (Expr*)BitfieldWidth; 1857 SourceLocation Loc = DeclStart; 1858 if (II) Loc = D.getIdentifierLoc(); 1859 1860 // FIXME: Unnamed fields can be handled in various different ways, for 1861 // example, unnamed unions inject all members into the struct namespace! 1862 1863 1864 if (BitWidth) { 1865 // TODO: Validate. 1866 //printf("WARNING: BITFIELDS IGNORED!\n"); 1867 1868 // 6.7.2.1p3 1869 // 6.7.2.1p4 1870 1871 } else { 1872 // Not a bitfield. 1873 1874 // validate II. 1875 1876 } 1877 1878 QualType T = GetTypeForDeclarator(D, S); 1879 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1880 bool InvalidDecl = false; 1881 1882 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1883 // than a variably modified type. 1884 if (T->isVariablyModifiedType()) { 1885 // FIXME: This diagnostic needs work 1886 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1887 InvalidDecl = true; 1888 } 1889 1890 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1891 1892 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1893 D.getAttributes()); 1894 1895 if (D.getInvalidType() || InvalidDecl) 1896 NewID->setInvalidDecl(); 1897 // If we have visibility info, make sure the AST is set accordingly. 1898 if (Visibility != tok::objc_not_keyword) 1899 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1900 return NewID; 1901} 1902 1903void Sema::ActOnFields(Scope* S, 1904 SourceLocation RecLoc, DeclTy *RecDecl, 1905 DeclTy **Fields, unsigned NumFields, 1906 SourceLocation LBrac, SourceLocation RBrac) { 1907 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1908 assert(EnclosingDecl && "missing record or interface decl"); 1909 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1910 1911 if (Record && Record->isDefinition()) { 1912 // Diagnose code like: 1913 // struct S { struct S {} X; }; 1914 // We discover this when we complete the outer S. Reject and ignore the 1915 // outer S. 1916 Diag(Record->getLocation(), diag::err_nested_redefinition, 1917 Record->getKindName()); 1918 Diag(RecLoc, diag::err_previous_definition); 1919 Record->setInvalidDecl(); 1920 return; 1921 } 1922 // Verify that all the fields are okay. 1923 unsigned NumNamedMembers = 0; 1924 llvm::SmallVector<FieldDecl*, 32> RecFields; 1925 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1926 1927 for (unsigned i = 0; i != NumFields; ++i) { 1928 1929 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1930 assert(FD && "missing field decl"); 1931 1932 // Remember all fields. 1933 RecFields.push_back(FD); 1934 1935 // Get the type for the field. 1936 Type *FDTy = FD->getType().getTypePtr(); 1937 1938 // C99 6.7.2.1p2 - A field may not be a function type. 1939 if (FDTy->isFunctionType()) { 1940 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1941 FD->getName()); 1942 FD->setInvalidDecl(); 1943 EnclosingDecl->setInvalidDecl(); 1944 continue; 1945 } 1946 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 1947 if (FDTy->isIncompleteType()) { 1948 if (!Record) { // Incomplete ivar type is always an error. 1949 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1950 FD->setInvalidDecl(); 1951 EnclosingDecl->setInvalidDecl(); 1952 continue; 1953 } 1954 if (i != NumFields-1 || // ... that the last member ... 1955 !Record->isStruct() || // ... of a structure ... 1956 !FDTy->isArrayType()) { //... may have incomplete array type. 1957 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1958 FD->setInvalidDecl(); 1959 EnclosingDecl->setInvalidDecl(); 1960 continue; 1961 } 1962 if (NumNamedMembers < 1) { //... must have more than named member ... 1963 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 1964 FD->getName()); 1965 FD->setInvalidDecl(); 1966 EnclosingDecl->setInvalidDecl(); 1967 continue; 1968 } 1969 // Okay, we have a legal flexible array member at the end of the struct. 1970 if (Record) 1971 Record->setHasFlexibleArrayMember(true); 1972 } 1973 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 1974 /// field of another structure or the element of an array. 1975 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 1976 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 1977 // If this is a member of a union, then entire union becomes "flexible". 1978 if (Record && Record->isUnion()) { 1979 Record->setHasFlexibleArrayMember(true); 1980 } else { 1981 // If this is a struct/class and this is not the last element, reject 1982 // it. Note that GCC supports variable sized arrays in the middle of 1983 // structures. 1984 if (i != NumFields-1) { 1985 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 1986 FD->getName()); 1987 FD->setInvalidDecl(); 1988 EnclosingDecl->setInvalidDecl(); 1989 continue; 1990 } 1991 // We support flexible arrays at the end of structs in other structs 1992 // as an extension. 1993 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 1994 FD->getName()); 1995 if (Record) 1996 Record->setHasFlexibleArrayMember(true); 1997 } 1998 } 1999 } 2000 /// A field cannot be an Objective-c object 2001 if (FDTy->isObjCInterfaceType()) { 2002 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2003 FD->getName()); 2004 FD->setInvalidDecl(); 2005 EnclosingDecl->setInvalidDecl(); 2006 continue; 2007 } 2008 // Keep track of the number of named members. 2009 if (IdentifierInfo *II = FD->getIdentifier()) { 2010 // Detect duplicate member names. 2011 if (!FieldIDs.insert(II)) { 2012 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2013 // Find the previous decl. 2014 SourceLocation PrevLoc; 2015 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 2016 assert(i != e && "Didn't find previous def!"); 2017 if (RecFields[i]->getIdentifier() == II) { 2018 PrevLoc = RecFields[i]->getLocation(); 2019 break; 2020 } 2021 } 2022 Diag(PrevLoc, diag::err_previous_definition); 2023 FD->setInvalidDecl(); 2024 EnclosingDecl->setInvalidDecl(); 2025 continue; 2026 } 2027 ++NumNamedMembers; 2028 } 2029 } 2030 2031 // Okay, we successfully defined 'Record'. 2032 if (Record) { 2033 Record->defineBody(&RecFields[0], RecFields.size()); 2034 Consumer.HandleTagDeclDefinition(Record); 2035 } else { 2036 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2037 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2038 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2039 else if (ObjCImplementationDecl *IMPDecl = 2040 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2041 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2042 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2043 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2044 } 2045 } 2046} 2047 2048Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2049 DeclTy *lastEnumConst, 2050 SourceLocation IdLoc, IdentifierInfo *Id, 2051 SourceLocation EqualLoc, ExprTy *val) { 2052 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2053 EnumConstantDecl *LastEnumConst = 2054 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2055 Expr *Val = static_cast<Expr*>(val); 2056 2057 // The scope passed in may not be a decl scope. Zip up the scope tree until 2058 // we find one that is. 2059 while ((S->getFlags() & Scope::DeclScope) == 0) 2060 S = S->getParent(); 2061 2062 // Verify that there isn't already something declared with this name in this 2063 // scope. 2064 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2065 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 2066 if (isa<EnumConstantDecl>(PrevDecl)) 2067 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2068 else 2069 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2070 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2071 delete Val; 2072 return 0; 2073 } 2074 } 2075 2076 llvm::APSInt EnumVal(32); 2077 QualType EltTy; 2078 if (Val) { 2079 // Make sure to promote the operand type to int. 2080 UsualUnaryConversions(Val); 2081 2082 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2083 SourceLocation ExpLoc; 2084 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2085 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2086 Id->getName()); 2087 delete Val; 2088 Val = 0; // Just forget about it. 2089 } else { 2090 EltTy = Val->getType(); 2091 } 2092 } 2093 2094 if (!Val) { 2095 if (LastEnumConst) { 2096 // Assign the last value + 1. 2097 EnumVal = LastEnumConst->getInitVal(); 2098 ++EnumVal; 2099 2100 // Check for overflow on increment. 2101 if (EnumVal < LastEnumConst->getInitVal()) 2102 Diag(IdLoc, diag::warn_enum_value_overflow); 2103 2104 EltTy = LastEnumConst->getType(); 2105 } else { 2106 // First value, set to zero. 2107 EltTy = Context.IntTy; 2108 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2109 } 2110 } 2111 2112 EnumConstantDecl *New = 2113 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2114 Val, EnumVal, 2115 LastEnumConst); 2116 2117 // Register this decl in the current scope stack. 2118 PushOnScopeChains(New, S); 2119 return New; 2120} 2121 2122void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2123 DeclTy **Elements, unsigned NumElements) { 2124 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2125 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 2126 2127 // TODO: If the result value doesn't fit in an int, it must be a long or long 2128 // long value. ISO C does not support this, but GCC does as an extension, 2129 // emit a warning. 2130 unsigned IntWidth = Context.Target.getIntWidth(); 2131 2132 // Verify that all the values are okay, compute the size of the values, and 2133 // reverse the list. 2134 unsigned NumNegativeBits = 0; 2135 unsigned NumPositiveBits = 0; 2136 2137 // Keep track of whether all elements have type int. 2138 bool AllElementsInt = true; 2139 2140 EnumConstantDecl *EltList = 0; 2141 for (unsigned i = 0; i != NumElements; ++i) { 2142 EnumConstantDecl *ECD = 2143 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2144 if (!ECD) continue; // Already issued a diagnostic. 2145 2146 // If the enum value doesn't fit in an int, emit an extension warning. 2147 const llvm::APSInt &InitVal = ECD->getInitVal(); 2148 assert(InitVal.getBitWidth() >= IntWidth && 2149 "Should have promoted value to int"); 2150 if (InitVal.getBitWidth() > IntWidth) { 2151 llvm::APSInt V(InitVal); 2152 V.trunc(IntWidth); 2153 V.extend(InitVal.getBitWidth()); 2154 if (V != InitVal) 2155 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2156 InitVal.toString()); 2157 } 2158 2159 // Keep track of the size of positive and negative values. 2160 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2161 NumPositiveBits = std::max(NumPositiveBits, 2162 (unsigned)InitVal.getActiveBits()); 2163 else 2164 NumNegativeBits = std::max(NumNegativeBits, 2165 (unsigned)InitVal.getMinSignedBits()); 2166 2167 // Keep track of whether every enum element has type int (very commmon). 2168 if (AllElementsInt) 2169 AllElementsInt = ECD->getType() == Context.IntTy; 2170 2171 ECD->setNextDeclarator(EltList); 2172 EltList = ECD; 2173 } 2174 2175 // Figure out the type that should be used for this enum. 2176 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2177 QualType BestType; 2178 unsigned BestWidth; 2179 2180 if (NumNegativeBits) { 2181 // If there is a negative value, figure out the smallest integer type (of 2182 // int/long/longlong) that fits. 2183 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2184 BestType = Context.IntTy; 2185 BestWidth = IntWidth; 2186 } else { 2187 BestWidth = Context.Target.getLongWidth(); 2188 2189 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2190 BestType = Context.LongTy; 2191 else { 2192 BestWidth = Context.Target.getLongLongWidth(); 2193 2194 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2195 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2196 BestType = Context.LongLongTy; 2197 } 2198 } 2199 } else { 2200 // If there is no negative value, figure out which of uint, ulong, ulonglong 2201 // fits. 2202 if (NumPositiveBits <= IntWidth) { 2203 BestType = Context.UnsignedIntTy; 2204 BestWidth = IntWidth; 2205 } else if (NumPositiveBits <= 2206 (BestWidth = Context.Target.getLongWidth())) { 2207 BestType = Context.UnsignedLongTy; 2208 } else { 2209 BestWidth = Context.Target.getLongLongWidth(); 2210 assert(NumPositiveBits <= BestWidth && 2211 "How could an initializer get larger than ULL?"); 2212 BestType = Context.UnsignedLongLongTy; 2213 } 2214 } 2215 2216 // Loop over all of the enumerator constants, changing their types to match 2217 // the type of the enum if needed. 2218 for (unsigned i = 0; i != NumElements; ++i) { 2219 EnumConstantDecl *ECD = 2220 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2221 if (!ECD) continue; // Already issued a diagnostic. 2222 2223 // Standard C says the enumerators have int type, but we allow, as an 2224 // extension, the enumerators to be larger than int size. If each 2225 // enumerator value fits in an int, type it as an int, otherwise type it the 2226 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2227 // that X has type 'int', not 'unsigned'. 2228 if (ECD->getType() == Context.IntTy) { 2229 // Make sure the init value is signed. 2230 llvm::APSInt IV = ECD->getInitVal(); 2231 IV.setIsSigned(true); 2232 ECD->setInitVal(IV); 2233 continue; // Already int type. 2234 } 2235 2236 // Determine whether the value fits into an int. 2237 llvm::APSInt InitVal = ECD->getInitVal(); 2238 bool FitsInInt; 2239 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2240 FitsInInt = InitVal.getActiveBits() < IntWidth; 2241 else 2242 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2243 2244 // If it fits into an integer type, force it. Otherwise force it to match 2245 // the enum decl type. 2246 QualType NewTy; 2247 unsigned NewWidth; 2248 bool NewSign; 2249 if (FitsInInt) { 2250 NewTy = Context.IntTy; 2251 NewWidth = IntWidth; 2252 NewSign = true; 2253 } else if (ECD->getType() == BestType) { 2254 // Already the right type! 2255 continue; 2256 } else { 2257 NewTy = BestType; 2258 NewWidth = BestWidth; 2259 NewSign = BestType->isSignedIntegerType(); 2260 } 2261 2262 // Adjust the APSInt value. 2263 InitVal.extOrTrunc(NewWidth); 2264 InitVal.setIsSigned(NewSign); 2265 ECD->setInitVal(InitVal); 2266 2267 // Adjust the Expr initializer and type. 2268 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2269 ECD->setType(NewTy); 2270 } 2271 2272 Enum->defineElements(EltList, BestType); 2273 Consumer.HandleTagDeclDefinition(Enum); 2274} 2275 2276Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2277 ExprTy *expr) { 2278 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2279 2280 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2281} 2282 2283Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2284 SourceLocation LBrace, 2285 SourceLocation RBrace, 2286 const char *Lang, 2287 unsigned StrSize, 2288 DeclTy *D) { 2289 LinkageSpecDecl::LanguageIDs Language; 2290 Decl *dcl = static_cast<Decl *>(D); 2291 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2292 Language = LinkageSpecDecl::lang_c; 2293 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2294 Language = LinkageSpecDecl::lang_cxx; 2295 else { 2296 Diag(Loc, diag::err_bad_language); 2297 return 0; 2298 } 2299 2300 // FIXME: Add all the various semantics of linkage specifications 2301 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2302} 2303 2304void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { 2305 2306 switch (Attr->getKind()) { 2307 case AttributeList::AT_vector_size: 2308 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2309 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 2310 if (!newType.isNull()) // install the new vector type into the decl 2311 vDecl->setType(newType); 2312 } 2313 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2314 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 2315 Attr); 2316 if (!newType.isNull()) // install the new vector type into the decl 2317 tDecl->setUnderlyingType(newType); 2318 } 2319 break; 2320 case AttributeList::AT_ext_vector_type: 2321 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 2322 HandleExtVectorTypeAttribute(tDecl, Attr); 2323 else 2324 Diag(Attr->getLoc(), 2325 diag::err_typecheck_ext_vector_not_typedef); 2326 break; 2327 case AttributeList::AT_address_space: 2328 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2329 QualType newType = HandleAddressSpaceTypeAttribute( 2330 tDecl->getUnderlyingType(), 2331 Attr); 2332 tDecl->setUnderlyingType(newType); 2333 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2334 QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), 2335 Attr); 2336 // install the new addr spaced type into the decl 2337 vDecl->setType(newType); 2338 } 2339 break; 2340 case AttributeList::AT_mode: 2341 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2342 QualType newType = HandleModeTypeAttribute(tDecl->getUnderlyingType(), 2343 Attr); 2344 tDecl->setUnderlyingType(newType); 2345 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2346 QualType newType = HandleModeTypeAttribute(vDecl->getType(), Attr); 2347 vDecl->setType(newType); 2348 } 2349 // FIXME: Diagnostic? 2350 break; 2351 case AttributeList::AT_alias: 2352 HandleAliasAttribute(New, Attr); 2353 break; 2354 case AttributeList::AT_deprecated: 2355 HandleDeprecatedAttribute(New, Attr); 2356 break; 2357 case AttributeList::AT_visibility: 2358 HandleVisibilityAttribute(New, Attr); 2359 break; 2360 case AttributeList::AT_weak: 2361 HandleWeakAttribute(New, Attr); 2362 break; 2363 case AttributeList::AT_dllimport: 2364 HandleDLLImportAttribute(New, Attr); 2365 break; 2366 case AttributeList::AT_dllexport: 2367 HandleDLLExportAttribute(New, Attr); 2368 break; 2369 case AttributeList::AT_nothrow: 2370 HandleNothrowAttribute(New, Attr); 2371 break; 2372 case AttributeList::AT_stdcall: 2373 HandleStdCallAttribute(New, Attr); 2374 break; 2375 case AttributeList::AT_fastcall: 2376 HandleFastCallAttribute(New, Attr); 2377 break; 2378 case AttributeList::AT_aligned: 2379 HandleAlignedAttribute(New, Attr); 2380 break; 2381 case AttributeList::AT_packed: 2382 HandlePackedAttribute(New, Attr); 2383 break; 2384 case AttributeList::AT_annotate: 2385 HandleAnnotateAttribute(New, Attr); 2386 break; 2387 case AttributeList::AT_noreturn: 2388 HandleNoReturnAttribute(New, Attr); 2389 break; 2390 case AttributeList::AT_format: 2391 HandleFormatAttribute(New, Attr); 2392 break; 2393 case AttributeList::AT_transparent_union: 2394 HandleTransparentUnionAttribute(New, Attr); 2395 break; 2396 default: 2397#if 0 2398 // TODO: when we have the full set of attributes, warn about unknown ones. 2399 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 2400 Attr->getName()->getName()); 2401#endif 2402 break; 2403 } 2404} 2405 2406void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, 2407 AttributeList *declarator_postfix) { 2408 while (declspec_prefix) { 2409 HandleDeclAttribute(New, declspec_prefix); 2410 declspec_prefix = declspec_prefix->getNext(); 2411 } 2412 while (declarator_postfix) { 2413 HandleDeclAttribute(New, declarator_postfix); 2414 declarator_postfix = declarator_postfix->getNext(); 2415 } 2416} 2417 2418void Sema::HandleExtVectorTypeAttribute(TypedefDecl *tDecl, 2419 AttributeList *rawAttr) { 2420 QualType curType = tDecl->getUnderlyingType(); 2421 // check the attribute arguments. 2422 if (rawAttr->getNumArgs() != 1) { 2423 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2424 std::string("1")); 2425 return; 2426 } 2427 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2428 llvm::APSInt vecSize(32); 2429 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2430 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2431 "ext_vector_type", sizeExpr->getSourceRange()); 2432 return; 2433 } 2434 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2435 // in conjunction with complex types (pointers, arrays, functions, etc.). 2436 Type *canonType = curType.getCanonicalType().getTypePtr(); 2437 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2438 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2439 curType.getCanonicalType().getAsString()); 2440 return; 2441 } 2442 // unlike gcc's vector_size attribute, the size is specified as the 2443 // number of elements, not the number of bytes. 2444 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2445 2446 if (vectorSize == 0) { 2447 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2448 sizeExpr->getSourceRange()); 2449 return; 2450 } 2451 // Instantiate/Install the vector type, the number of elements is > 0. 2452 tDecl->setUnderlyingType(Context.getExtVectorType(curType, vectorSize)); 2453 // Remember this typedef decl, we will need it later for diagnostics. 2454 ExtVectorDecls.push_back(tDecl); 2455} 2456 2457QualType Sema::HandleVectorTypeAttribute(QualType curType, 2458 AttributeList *rawAttr) { 2459 // check the attribute arugments. 2460 if (rawAttr->getNumArgs() != 1) { 2461 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2462 std::string("1")); 2463 return QualType(); 2464 } 2465 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2466 llvm::APSInt vecSize(32); 2467 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2468 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2469 "vector_size", sizeExpr->getSourceRange()); 2470 return QualType(); 2471 } 2472 // navigate to the base type - we need to provide for vector pointers, 2473 // vector arrays, and functions returning vectors. 2474 Type *canonType = curType.getCanonicalType().getTypePtr(); 2475 2476 if (canonType->isPointerType() || canonType->isArrayType() || 2477 canonType->isFunctionType()) { 2478 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2479 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2480 do { 2481 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2482 canonType = PT->getPointeeType().getTypePtr(); 2483 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2484 canonType = AT->getElementType().getTypePtr(); 2485 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2486 canonType = FT->getResultType().getTypePtr(); 2487 } while (canonType->isPointerType() || canonType->isArrayType() || 2488 canonType->isFunctionType()); 2489 */ 2490 } 2491 // the base type must be integer or float. 2492 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2493 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2494 curType.getCanonicalType().getAsString()); 2495 return QualType(); 2496 } 2497 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2498 // vecSize is specified in bytes - convert to bits. 2499 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2500 2501 // the vector size needs to be an integral multiple of the type size. 2502 if (vectorSize % typeSize) { 2503 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2504 sizeExpr->getSourceRange()); 2505 return QualType(); 2506 } 2507 if (vectorSize == 0) { 2508 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2509 sizeExpr->getSourceRange()); 2510 return QualType(); 2511 } 2512 // Instantiate the vector type, the number of elements is > 0, and not 2513 // required to be a power of 2, unlike GCC. 2514 return Context.getVectorType(curType, vectorSize/typeSize); 2515} 2516 2517void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { 2518 // check the attribute arguments. 2519 if (rawAttr->getNumArgs() > 0) { 2520 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2521 std::string("0")); 2522 return; 2523 } 2524 2525 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2526 TD->addAttr(new PackedAttr); 2527 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2528 // If the alignment is less than or equal to 8 bits, the packed attribute 2529 // has no effect. 2530 if (!FD->getType()->isIncompleteType() && 2531 Context.getTypeAlign(FD->getType()) <= 8) 2532 Diag(rawAttr->getLoc(), 2533 diag::warn_attribute_ignored_for_field_of_type, 2534 rawAttr->getName()->getName(), FD->getType().getAsString()); 2535 else 2536 FD->addAttr(new PackedAttr); 2537 } else 2538 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2539 rawAttr->getName()->getName()); 2540} 2541 2542void Sema::HandleAliasAttribute(Decl *d, AttributeList *rawAttr) { 2543 // check the attribute arguments. 2544 if (rawAttr->getNumArgs() != 1) { 2545 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2546 std::string("1")); 2547 return; 2548 } 2549 2550 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2551 Arg = Arg->IgnoreParenCasts(); 2552 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2553 2554 if (Str == 0 || Str->isWide()) { 2555 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2556 "alias", std::string("1")); 2557 return; 2558 } 2559 2560 const char *Alias = Str->getStrData(); 2561 unsigned AliasLen = Str->getByteLength(); 2562 2563 // FIXME: check if target symbol exists in current file 2564 2565 d->addAttr(new AliasAttr(std::string(Alias, AliasLen))); 2566} 2567 2568void Sema::HandleNoReturnAttribute(Decl *d, AttributeList *rawAttr) { 2569 // check the attribute arguments. 2570 if (rawAttr->getNumArgs() != 0) { 2571 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2572 std::string("0")); 2573 return; 2574 } 2575 2576 FunctionDecl *Fn = dyn_cast<FunctionDecl>(d); 2577 2578 if (!Fn) { 2579 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2580 "noreturn", "function"); 2581 return; 2582 } 2583 2584 d->addAttr(new NoReturnAttr()); 2585} 2586 2587void Sema::HandleDeprecatedAttribute(Decl *d, AttributeList *rawAttr) { 2588 // check the attribute arguments. 2589 if (rawAttr->getNumArgs() != 0) { 2590 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2591 std::string("0")); 2592 return; 2593 } 2594 2595 d->addAttr(new DeprecatedAttr()); 2596} 2597 2598void Sema::HandleVisibilityAttribute(Decl *d, AttributeList *rawAttr) { 2599 // check the attribute arguments. 2600 if (rawAttr->getNumArgs() != 1) { 2601 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2602 std::string("1")); 2603 return; 2604 } 2605 2606 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2607 Arg = Arg->IgnoreParenCasts(); 2608 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2609 2610 if (Str == 0 || Str->isWide()) { 2611 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2612 "visibility", std::string("1")); 2613 return; 2614 } 2615 2616 const char *TypeStr = Str->getStrData(); 2617 unsigned TypeLen = Str->getByteLength(); 2618 VisibilityAttr::VisibilityTypes type; 2619 2620 if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) 2621 type = VisibilityAttr::DefaultVisibility; 2622 else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) 2623 type = VisibilityAttr::HiddenVisibility; 2624 else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) 2625 type = VisibilityAttr::HiddenVisibility; // FIXME 2626 else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) 2627 type = VisibilityAttr::ProtectedVisibility; 2628 else { 2629 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2630 "visibility", TypeStr); 2631 return; 2632 } 2633 2634 d->addAttr(new VisibilityAttr(type)); 2635} 2636 2637void Sema::HandleWeakAttribute(Decl *d, AttributeList *rawAttr) { 2638 // check the attribute arguments. 2639 if (rawAttr->getNumArgs() != 0) { 2640 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2641 std::string("0")); 2642 return; 2643 } 2644 2645 d->addAttr(new WeakAttr()); 2646} 2647 2648void Sema::HandleDLLImportAttribute(Decl *d, AttributeList *rawAttr) { 2649 // check the attribute arguments. 2650 if (rawAttr->getNumArgs() != 0) { 2651 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2652 std::string("0")); 2653 return; 2654 } 2655 2656 d->addAttr(new DLLImportAttr()); 2657} 2658 2659void Sema::HandleDLLExportAttribute(Decl *d, AttributeList *rawAttr) { 2660 // check the attribute arguments. 2661 if (rawAttr->getNumArgs() != 0) { 2662 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2663 std::string("0")); 2664 return; 2665 } 2666 2667 d->addAttr(new DLLExportAttr()); 2668} 2669 2670void Sema::HandleStdCallAttribute(Decl *d, AttributeList *rawAttr) { 2671 // check the attribute arguments. 2672 if (rawAttr->getNumArgs() != 0) { 2673 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2674 std::string("0")); 2675 return; 2676 } 2677 2678 d->addAttr(new StdCallAttr()); 2679} 2680 2681void Sema::HandleFastCallAttribute(Decl *d, AttributeList *rawAttr) { 2682 // check the attribute arguments. 2683 if (rawAttr->getNumArgs() != 0) { 2684 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2685 std::string("0")); 2686 return; 2687 } 2688 2689 d->addAttr(new FastCallAttr()); 2690} 2691 2692void Sema::HandleNothrowAttribute(Decl *d, AttributeList *rawAttr) { 2693 // check the attribute arguments. 2694 if (rawAttr->getNumArgs() != 0) { 2695 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2696 std::string("0")); 2697 return; 2698 } 2699 2700 d->addAttr(new NoThrowAttr()); 2701} 2702 2703static const FunctionTypeProto *getFunctionProto(Decl *d) { 2704 QualType Ty; 2705 2706 if (ValueDecl *decl = dyn_cast<ValueDecl>(d)) 2707 Ty = decl->getType(); 2708 else if (FieldDecl *decl = dyn_cast<FieldDecl>(d)) 2709 Ty = decl->getType(); 2710 else if (TypedefDecl* decl = dyn_cast<TypedefDecl>(d)) 2711 Ty = decl->getUnderlyingType(); 2712 else 2713 return 0; 2714 2715 if (Ty->isFunctionPointerType()) { 2716 const PointerType *PtrTy = Ty->getAsPointerType(); 2717 Ty = PtrTy->getPointeeType(); 2718 } 2719 2720 if (const FunctionType *FnTy = Ty->getAsFunctionType()) 2721 return dyn_cast<FunctionTypeProto>(FnTy->getAsFunctionType()); 2722 2723 return 0; 2724} 2725 2726static inline bool isNSStringType(QualType T, ASTContext &Ctx) { 2727 if (!T->isPointerType()) 2728 return false; 2729 2730 T = T->getAsPointerType()->getPointeeType().getCanonicalType(); 2731 ObjCInterfaceType* ClsT = dyn_cast<ObjCInterfaceType>(T.getTypePtr()); 2732 2733 if (!ClsT) 2734 return false; 2735 2736 IdentifierInfo* ClsName = ClsT->getDecl()->getIdentifier(); 2737 2738 // FIXME: Should we walk the chain of classes? 2739 return ClsName == &Ctx.Idents.get("NSString") || 2740 ClsName == &Ctx.Idents.get("NSMutableString"); 2741} 2742 2743/// Handle __attribute__((format(type,idx,firstarg))) attributes 2744/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html 2745void Sema::HandleFormatAttribute(Decl *d, AttributeList *rawAttr) { 2746 2747 if (!rawAttr->getParameterName()) { 2748 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2749 "format", std::string("1")); 2750 return; 2751 } 2752 2753 if (rawAttr->getNumArgs() != 2) { 2754 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2755 std::string("3")); 2756 return; 2757 } 2758 2759 // GCC ignores the format attribute on K&R style function 2760 // prototypes, so we ignore it as well 2761 const FunctionTypeProto *proto = getFunctionProto(d); 2762 2763 if (!proto) { 2764 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2765 "format", "function"); 2766 return; 2767 } 2768 2769 // FIXME: in C++ the implicit 'this' function parameter also counts. 2770 // this is needed in order to be compatible with GCC 2771 // the index must start in 1 and the limit is numargs+1 2772 unsigned NumArgs = proto->getNumArgs(); 2773 unsigned FirstIdx = 1; 2774 2775 const char *Format = rawAttr->getParameterName()->getName(); 2776 unsigned FormatLen = rawAttr->getParameterName()->getLength(); 2777 2778 // Normalize the argument, __foo__ becomes foo. 2779 if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && 2780 Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { 2781 Format += 2; 2782 FormatLen -= 4; 2783 } 2784 2785 bool Supported = false; 2786 bool is_NSString = false; 2787 bool is_strftime = false; 2788 2789 switch (FormatLen) { 2790 default: break; 2791 case 5: 2792 Supported = !memcmp(Format, "scanf", 5); 2793 break; 2794 case 6: 2795 Supported = !memcmp(Format, "printf", 6); 2796 break; 2797 case 7: 2798 Supported = !memcmp(Format, "strfmon", 7); 2799 break; 2800 case 8: 2801 Supported = (is_strftime = !memcmp(Format, "strftime", 8)) || 2802 (is_NSString = !memcmp(Format, "NSString", 8)); 2803 break; 2804 } 2805 2806 if (!Supported) { 2807 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2808 "format", rawAttr->getParameterName()->getName()); 2809 return; 2810 } 2811 2812 // checks for the 2nd argument 2813 Expr *IdxExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2814 llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); 2815 if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { 2816 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2817 "format", std::string("2"), IdxExpr->getSourceRange()); 2818 return; 2819 } 2820 2821 if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { 2822 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2823 "format", std::string("2"), IdxExpr->getSourceRange()); 2824 return; 2825 } 2826 2827 // FIXME: Do we need to bounds check? 2828 unsigned ArgIdx = Idx.getZExtValue() - 1; 2829 2830 // make sure the format string is really a string 2831 QualType Ty = proto->getArgType(ArgIdx); 2832 2833 if (is_NSString) { 2834 // FIXME: do we need to check if the type is NSString*? What are 2835 // the semantics? 2836 if (!isNSStringType(Ty, Context)) { 2837 // FIXME: Should highlight the actual expression that has the 2838 // wrong type. 2839 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_NSString, 2840 IdxExpr->getSourceRange()); 2841 return; 2842 } 2843 } 2844 else if (!Ty->isPointerType() || 2845 !Ty->getAsPointerType()->getPointeeType()->isCharType()) { 2846 // FIXME: Should highlight the actual expression that has the 2847 // wrong type. 2848 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, 2849 IdxExpr->getSourceRange()); 2850 return; 2851 } 2852 2853 // check the 3rd argument 2854 Expr *FirstArgExpr = static_cast<Expr *>(rawAttr->getArg(1)); 2855 llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); 2856 if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { 2857 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2858 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2859 return; 2860 } 2861 2862 // check if the function is variadic if the 3rd argument non-zero 2863 if (FirstArg != 0) { 2864 if (proto->isVariadic()) { 2865 ++NumArgs; // +1 for ... 2866 } else { 2867 Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); 2868 return; 2869 } 2870 } 2871 2872 // strftime requires FirstArg to be 0 because it doesn't read from any variable 2873 // the input is just the current time + the format string 2874 if (is_strftime) { 2875 if (FirstArg != 0) { 2876 Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, 2877 FirstArgExpr->getSourceRange()); 2878 return; 2879 } 2880 // if 0 it disables parameter checking (to use with e.g. va_list) 2881 } else if (FirstArg != 0 && FirstArg != NumArgs) { 2882 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2883 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2884 return; 2885 } 2886 2887 d->addAttr(new FormatAttr(std::string(Format, FormatLen), 2888 Idx.getZExtValue(), FirstArg.getZExtValue())); 2889} 2890 2891void Sema::HandleTransparentUnionAttribute(Decl *d, AttributeList *rawAttr) { 2892 // check the attribute arguments. 2893 if (rawAttr->getNumArgs() != 0) { 2894 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2895 std::string("0")); 2896 return; 2897 } 2898 2899 TypeDecl *decl = dyn_cast<TypeDecl>(d); 2900 2901 if (!decl || !Context.getTypeDeclType(decl)->isUnionType()) { 2902 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2903 "transparent_union", "union"); 2904 return; 2905 } 2906 2907 //QualType QTy = Context.getTypeDeclType(decl); 2908 //const RecordType *Ty = QTy->getAsUnionType(); 2909 2910// FIXME 2911// Ty->addAttr(new TransparentUnionAttr()); 2912} 2913 2914void Sema::HandleAnnotateAttribute(Decl *d, AttributeList *rawAttr) { 2915 // check the attribute arguments. 2916 if (rawAttr->getNumArgs() != 1) { 2917 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2918 std::string("1")); 2919 return; 2920 } 2921 Expr *argExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2922 StringLiteral *SE = dyn_cast<StringLiteral>(argExpr); 2923 2924 // Make sure that there is a string literal as the annotation's single 2925 // argument. 2926 if (!SE) { 2927 Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); 2928 return; 2929 } 2930 d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), 2931 SE->getByteLength()))); 2932} 2933 2934void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr) 2935{ 2936 // check the attribute arguments. 2937 if (rawAttr->getNumArgs() > 1) { 2938 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2939 std::string("1")); 2940 return; 2941 } 2942 2943 unsigned Align = 0; 2944 2945 if (rawAttr->getNumArgs() == 0) { 2946 // FIXME: This should be the target specific maximum alignment. 2947 // (For now we just use 128 bits which is the maximum on X86. 2948 Align = 128; 2949 return; 2950 } else { 2951 Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2952 llvm::APSInt alignment(32); 2953 if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { 2954 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2955 "aligned", alignmentExpr->getSourceRange()); 2956 return; 2957 } 2958 2959 Align = alignment.getZExtValue() * 8; 2960 } 2961 2962 d->addAttr(new AlignedAttr(Align)); 2963} 2964