SemaDecl.cpp revision 6f0200e9ebf7f65df74b3cf55b4319b075b244a2
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28using namespace clang; 29 30Sema::TypeTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 31 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 32 33 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 34 isa<ObjCInterfaceDecl>(IIDecl) || 35 isa<TagDecl>(IIDecl))) 36 return IIDecl; 37 return 0; 38} 39 40DeclContext *Sema::getDCParent(DeclContext *DC) { 41 // If CurContext is a ObjC method, getParent() will return NULL. 42 if (isa<ObjCMethodDecl>(DC)) 43 return Context.getTranslationUnitDecl(); 44 45 // A C++ inline method is parsed *after* the topmost class it was declared in 46 // is fully parsed (it's "complete"). 47 // The parsing of a C++ inline method happens at the declaration context of 48 // the topmost (non-nested) class it is declared in. 49 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 50 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 51 DC = MD->getParent(); 52 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getParent())) 53 DC = RD; 54 55 // Return the declaration context of the topmost class the inline method is 56 // declared in. 57 return DC; 58 } 59 60 return DC->getParent(); 61} 62 63void Sema::PushDeclContext(DeclContext *DC) { 64 assert(getDCParent(DC) == CurContext && 65 "The next DeclContext should be directly contained in the current one."); 66 CurContext = DC; 67} 68 69void Sema::PopDeclContext() { 70 assert(CurContext && "DeclContext imbalance!"); 71 CurContext = getDCParent(CurContext); 72} 73 74/// Add this decl to the scope shadowed decl chains. 75void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 76 S->AddDecl(D); 77 78 // C++ [basic.scope]p4: 79 // -- exactly one declaration shall declare a class name or 80 // enumeration name that is not a typedef name and the other 81 // declarations shall all refer to the same object or 82 // enumerator, or all refer to functions and function templates; 83 // in this case the class name or enumeration name is hidden. 84 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 85 // We are pushing the name of a tag (enum or class). 86 IdentifierResolver::iterator 87 I = IdResolver.begin(TD->getIdentifier(), 88 TD->getDeclContext(), false/*LookInParentCtx*/); 89 if (I != IdResolver.end() && 90 IdResolver.isDeclInScope(*I, TD->getDeclContext(), S)) { 91 // There is already a declaration with the same name in the same 92 // scope. It must be found before we find the new declaration, 93 // so swap the order on the shadowed declaration chain. 94 95 IdResolver.AddShadowedDecl(TD, *I); 96 return; 97 } 98 } 99 IdResolver.AddDecl(D); 100} 101 102void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 103 if (S->decl_empty()) return; 104 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 105 106 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 107 I != E; ++I) { 108 Decl *TmpD = static_cast<Decl*>(*I); 109 assert(TmpD && "This decl didn't get pushed??"); 110 111 if (isa<CXXFieldDecl>(TmpD)) continue; 112 113 assert(isa<ScopedDecl>(TmpD) && "Decl isn't ScopedDecl?"); 114 ScopedDecl *D = cast<ScopedDecl>(TmpD); 115 116 IdentifierInfo *II = D->getIdentifier(); 117 if (!II) continue; 118 119 // We only want to remove the decls from the identifier decl chains for 120 // local scopes, when inside a function/method. 121 if (S->getFnParent() != 0) 122 IdResolver.RemoveDecl(D); 123 124 // Chain this decl to the containing DeclContext. 125 D->setNext(CurContext->getDeclChain()); 126 CurContext->setDeclChain(D); 127 } 128} 129 130/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 131/// return 0 if one not found. 132ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 133 // The third "scope" argument is 0 since we aren't enabling lazy built-in 134 // creation from this context. 135 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 136 137 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 138} 139 140/// LookupDecl - Look up the inner-most declaration in the specified 141/// namespace. 142Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 143 Scope *S, bool enableLazyBuiltinCreation) { 144 if (II == 0) return 0; 145 unsigned NS = NSI; 146 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 147 NS |= Decl::IDNS_Tag; 148 149 // Scan up the scope chain looking for a decl that matches this identifier 150 // that is in the appropriate namespace. This search should not take long, as 151 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 152 for (IdentifierResolver::iterator 153 I = IdResolver.begin(II, CurContext), E = IdResolver.end(); I != E; ++I) 154 if ((*I)->getIdentifierNamespace() & NS) 155 return *I; 156 157 // If we didn't find a use of this identifier, and if the identifier 158 // corresponds to a compiler builtin, create the decl object for the builtin 159 // now, injecting it into translation unit scope, and return it. 160 if (NS & Decl::IDNS_Ordinary) { 161 if (enableLazyBuiltinCreation) { 162 // If this is a builtin on this (or all) targets, create the decl. 163 if (unsigned BuiltinID = II->getBuiltinID()) 164 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 165 } 166 if (getLangOptions().ObjC1) { 167 // @interface and @compatibility_alias introduce typedef-like names. 168 // Unlike typedef's, they can only be introduced at file-scope (and are 169 // therefore not scoped decls). They can, however, be shadowed by 170 // other names in IDNS_Ordinary. 171 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 172 if (IDI != ObjCInterfaceDecls.end()) 173 return IDI->second; 174 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 175 if (I != ObjCAliasDecls.end()) 176 return I->second->getClassInterface(); 177 } 178 } 179 return 0; 180} 181 182void Sema::InitBuiltinVaListType() { 183 if (!Context.getBuiltinVaListType().isNull()) 184 return; 185 186 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 187 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 188 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 189 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 190} 191 192/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 193/// lazily create a decl for it. 194ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 195 Scope *S) { 196 Builtin::ID BID = (Builtin::ID)bid; 197 198 if (BID == Builtin::BI__builtin_va_start || 199 BID == Builtin::BI__builtin_va_copy || 200 BID == Builtin::BI__builtin_va_end || 201 BID == Builtin::BI__builtin_stdarg_start) 202 InitBuiltinVaListType(); 203 204 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 205 FunctionDecl *New = FunctionDecl::Create(Context, 206 Context.getTranslationUnitDecl(), 207 SourceLocation(), II, R, 208 FunctionDecl::Extern, false, 0); 209 210 // Create Decl objects for each parameter, adding them to the 211 // FunctionDecl. 212 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 213 llvm::SmallVector<ParmVarDecl*, 16> Params; 214 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 215 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 216 FT->getArgType(i), VarDecl::None, 0, 217 0)); 218 New->setParams(&Params[0], Params.size()); 219 } 220 221 222 223 // TUScope is the translation-unit scope to insert this function into. 224 PushOnScopeChains(New, TUScope); 225 return New; 226} 227 228/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 229/// and scope as a previous declaration 'Old'. Figure out how to resolve this 230/// situation, merging decls or emitting diagnostics as appropriate. 231/// 232TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 233 // Verify the old decl was also a typedef. 234 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 235 if (!Old) { 236 Diag(New->getLocation(), diag::err_redefinition_different_kind, 237 New->getName()); 238 Diag(OldD->getLocation(), diag::err_previous_definition); 239 return New; 240 } 241 242 // If the typedef types are not identical, reject them in all languages and 243 // with any extensions enabled. 244 if (Old->getUnderlyingType() != New->getUnderlyingType() && 245 Context.getCanonicalType(Old->getUnderlyingType()) != 246 Context.getCanonicalType(New->getUnderlyingType())) { 247 Diag(New->getLocation(), diag::err_redefinition_different_typedef, 248 New->getUnderlyingType().getAsString(), 249 Old->getUnderlyingType().getAsString()); 250 Diag(Old->getLocation(), diag::err_previous_definition); 251 return Old; 252 } 253 254 // Allow multiple definitions for ObjC built-in typedefs. 255 // FIXME: Verify the underlying types are equivalent! 256 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 257 return Old; 258 259 if (getLangOptions().Microsoft) return New; 260 261 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 262 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 263 // *either* declaration is in a system header. The code below implements 264 // this adhoc compatibility rule. FIXME: The following code will not 265 // work properly when compiling ".i" files (containing preprocessed output). 266 SourceManager &SrcMgr = Context.getSourceManager(); 267 if (SrcMgr.isInSystemHeader(Old->getLocation())) 268 return New; 269 if (SrcMgr.isInSystemHeader(New->getLocation())) 270 return New; 271 272 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 273 Diag(Old->getLocation(), diag::err_previous_definition); 274 return New; 275} 276 277/// DeclhasAttr - returns true if decl Declaration already has the target 278/// attribute. 279static bool DeclHasAttr(const Decl *decl, const Attr *target) { 280 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 281 if (attr->getKind() == target->getKind()) 282 return true; 283 284 return false; 285} 286 287/// MergeAttributes - append attributes from the Old decl to the New one. 288static void MergeAttributes(Decl *New, Decl *Old) { 289 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 290 291 while (attr) { 292 tmp = attr; 293 attr = attr->getNext(); 294 295 if (!DeclHasAttr(New, tmp)) { 296 New->addAttr(tmp); 297 } else { 298 tmp->setNext(0); 299 delete(tmp); 300 } 301 } 302 303 Old->invalidateAttrs(); 304} 305 306/// MergeFunctionDecl - We just parsed a function 'New' from 307/// declarator D which has the same name and scope as a previous 308/// declaration 'Old'. Figure out how to resolve this situation, 309/// merging decls or emitting diagnostics as appropriate. 310/// Redeclaration will be set true if thisNew is a redeclaration OldD. 311FunctionDecl * 312Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 313 Redeclaration = false; 314 // Verify the old decl was also a function. 315 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 316 if (!Old) { 317 Diag(New->getLocation(), diag::err_redefinition_different_kind, 318 New->getName()); 319 Diag(OldD->getLocation(), diag::err_previous_definition); 320 return New; 321 } 322 323 QualType OldQType = Context.getCanonicalType(Old->getType()); 324 QualType NewQType = Context.getCanonicalType(New->getType()); 325 326 // C++ [dcl.fct]p3: 327 // All declarations for a function shall agree exactly in both the 328 // return type and the parameter-type-list. 329 if (getLangOptions().CPlusPlus && OldQType == NewQType) { 330 MergeAttributes(New, Old); 331 Redeclaration = true; 332 return MergeCXXFunctionDecl(New, Old); 333 } 334 335 // C: Function types need to be compatible, not identical. This handles 336 // duplicate function decls like "void f(int); void f(enum X);" properly. 337 if (!getLangOptions().CPlusPlus && 338 Context.typesAreCompatible(OldQType, NewQType)) { 339 MergeAttributes(New, Old); 340 Redeclaration = true; 341 return New; 342 } 343 344 // A function that has already been declared has been redeclared or defined 345 // with a different type- show appropriate diagnostic 346 diag::kind PrevDiag; 347 if (Old->isThisDeclarationADefinition()) 348 PrevDiag = diag::err_previous_definition; 349 else if (Old->isImplicit()) 350 PrevDiag = diag::err_previous_implicit_declaration; 351 else 352 PrevDiag = diag::err_previous_declaration; 353 354 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 355 // TODO: This is totally simplistic. It should handle merging functions 356 // together etc, merging extern int X; int X; ... 357 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 358 Diag(Old->getLocation(), PrevDiag); 359 return New; 360} 361 362/// Predicate for C "tentative" external object definitions (C99 6.9.2). 363static bool isTentativeDefinition(VarDecl *VD) { 364 if (VD->isFileVarDecl()) 365 return (!VD->getInit() && 366 (VD->getStorageClass() == VarDecl::None || 367 VD->getStorageClass() == VarDecl::Static)); 368 return false; 369} 370 371/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 372/// when dealing with C "tentative" external object definitions (C99 6.9.2). 373void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 374 bool VDIsTentative = isTentativeDefinition(VD); 375 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 376 377 for (IdentifierResolver::iterator 378 I = IdResolver.begin(VD->getIdentifier(), 379 VD->getDeclContext(), false/*LookInParentCtx*/), 380 E = IdResolver.end(); I != E; ++I) { 381 if (*I != VD && IdResolver.isDeclInScope(*I, VD->getDeclContext(), S)) { 382 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 383 384 // Handle the following case: 385 // int a[10]; 386 // int a[]; - the code below makes sure we set the correct type. 387 // int a[11]; - this is an error, size isn't 10. 388 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 389 OldDecl->getType()->isConstantArrayType()) 390 VD->setType(OldDecl->getType()); 391 392 // Check for "tentative" definitions. We can't accomplish this in 393 // MergeVarDecl since the initializer hasn't been attached. 394 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 395 continue; 396 397 // Handle __private_extern__ just like extern. 398 if (OldDecl->getStorageClass() != VarDecl::Extern && 399 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 400 VD->getStorageClass() != VarDecl::Extern && 401 VD->getStorageClass() != VarDecl::PrivateExtern) { 402 Diag(VD->getLocation(), diag::err_redefinition, VD->getName()); 403 Diag(OldDecl->getLocation(), diag::err_previous_definition); 404 } 405 } 406 } 407} 408 409/// MergeVarDecl - We just parsed a variable 'New' which has the same name 410/// and scope as a previous declaration 'Old'. Figure out how to resolve this 411/// situation, merging decls or emitting diagnostics as appropriate. 412/// 413/// Tentative definition rules (C99 6.9.2p2) are checked by 414/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 415/// definitions here, since the initializer hasn't been attached. 416/// 417VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 418 // Verify the old decl was also a variable. 419 VarDecl *Old = dyn_cast<VarDecl>(OldD); 420 if (!Old) { 421 Diag(New->getLocation(), diag::err_redefinition_different_kind, 422 New->getName()); 423 Diag(OldD->getLocation(), diag::err_previous_definition); 424 return New; 425 } 426 427 MergeAttributes(New, Old); 428 429 // Verify the types match. 430 QualType OldCType = Context.getCanonicalType(Old->getType()); 431 QualType NewCType = Context.getCanonicalType(New->getType()); 432 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 433 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 434 Diag(Old->getLocation(), diag::err_previous_definition); 435 return New; 436 } 437 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 438 if (New->getStorageClass() == VarDecl::Static && 439 (Old->getStorageClass() == VarDecl::None || 440 Old->getStorageClass() == VarDecl::Extern)) { 441 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 442 Diag(Old->getLocation(), diag::err_previous_definition); 443 return New; 444 } 445 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 446 if (New->getStorageClass() != VarDecl::Static && 447 Old->getStorageClass() == VarDecl::Static) { 448 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 449 Diag(Old->getLocation(), diag::err_previous_definition); 450 return New; 451 } 452 // File scoped variables are analyzed in FinalizeDeclaratorGroup. 453 if (!New->isFileVarDecl()) { 454 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 455 Diag(Old->getLocation(), diag::err_previous_definition); 456 } 457 return New; 458} 459 460/// CheckParmsForFunctionDef - Check that the parameters of the given 461/// function are appropriate for the definition of a function. This 462/// takes care of any checks that cannot be performed on the 463/// declaration itself, e.g., that the types of each of the function 464/// parameters are complete. 465bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 466 bool HasInvalidParm = false; 467 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 468 ParmVarDecl *Param = FD->getParamDecl(p); 469 470 // C99 6.7.5.3p4: the parameters in a parameter type list in a 471 // function declarator that is part of a function definition of 472 // that function shall not have incomplete type. 473 if (Param->getType()->isIncompleteType() && 474 !Param->isInvalidDecl()) { 475 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 476 Param->getType().getAsString()); 477 Param->setInvalidDecl(); 478 HasInvalidParm = true; 479 } 480 } 481 482 return HasInvalidParm; 483} 484 485/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 486/// no declarator (e.g. "struct foo;") is parsed. 487Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 488 // TODO: emit error on 'int;' or 'const enum foo;'. 489 // TODO: emit error on 'typedef int;' 490 // if (!DS.isMissingDeclaratorOk()) Diag(...); 491 492 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 493} 494 495bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 496 // Get the type before calling CheckSingleAssignmentConstraints(), since 497 // it can promote the expression. 498 QualType InitType = Init->getType(); 499 500 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 501 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 502 InitType, Init, "initializing"); 503} 504 505bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 506 const ArrayType *AT = Context.getAsArrayType(DeclT); 507 508 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 509 // C99 6.7.8p14. We have an array of character type with unknown size 510 // being initialized to a string literal. 511 llvm::APSInt ConstVal(32); 512 ConstVal = strLiteral->getByteLength() + 1; 513 // Return a new array type (C99 6.7.8p22). 514 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 515 ArrayType::Normal, 0); 516 } else { 517 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 518 // C99 6.7.8p14. We have an array of character type with known size. 519 // FIXME: Avoid truncation for 64-bit length strings. 520 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 521 Diag(strLiteral->getSourceRange().getBegin(), 522 diag::warn_initializer_string_for_char_array_too_long, 523 strLiteral->getSourceRange()); 524 } 525 // Set type from "char *" to "constant array of char". 526 strLiteral->setType(DeclT); 527 // For now, we always return false (meaning success). 528 return false; 529} 530 531StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 532 const ArrayType *AT = Context.getAsArrayType(DeclType); 533 if (AT && AT->getElementType()->isCharType()) { 534 return dyn_cast<StringLiteral>(Init); 535 } 536 return 0; 537} 538 539bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 540 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 541 // of unknown size ("[]") or an object type that is not a variable array type. 542 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 543 return Diag(VAT->getSizeExpr()->getLocStart(), 544 diag::err_variable_object_no_init, 545 VAT->getSizeExpr()->getSourceRange()); 546 547 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 548 if (!InitList) { 549 // FIXME: Handle wide strings 550 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 551 return CheckStringLiteralInit(strLiteral, DeclType); 552 553 if (DeclType->isArrayType()) 554 return Diag(Init->getLocStart(), 555 diag::err_array_init_list_required, 556 Init->getSourceRange()); 557 558 return CheckSingleInitializer(Init, DeclType); 559 } 560 561 InitListChecker CheckInitList(this, InitList, DeclType); 562 return CheckInitList.HadError(); 563} 564 565Sema::DeclTy * 566Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 567 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 568 IdentifierInfo *II = D.getIdentifier(); 569 570 // All of these full declarators require an identifier. If it doesn't have 571 // one, the ParsedFreeStandingDeclSpec action should be used. 572 if (II == 0) { 573 Diag(D.getDeclSpec().getSourceRange().getBegin(), 574 diag::err_declarator_need_ident, 575 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 576 return 0; 577 } 578 579 // The scope passed in may not be a decl scope. Zip up the scope tree until 580 // we find one that is. 581 while ((S->getFlags() & Scope::DeclScope) == 0) 582 S = S->getParent(); 583 584 // See if this is a redefinition of a variable in the same scope. 585 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 586 ScopedDecl *New; 587 bool InvalidDecl = false; 588 589 // In C++, the previous declaration we find might be a tag type 590 // (class or enum). In this case, the new declaration will hide the 591 // tag type. 592 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 593 PrevDecl = 0; 594 595 QualType R = GetTypeForDeclarator(D, S); 596 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 597 598 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 599 // Check that there are no default arguments (C++ only). 600 if (getLangOptions().CPlusPlus) 601 CheckExtraCXXDefaultArguments(D); 602 603 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 604 if (!NewTD) return 0; 605 606 // Handle attributes prior to checking for duplicates in MergeVarDecl 607 ProcessDeclAttributes(NewTD, D); 608 // Merge the decl with the existing one if appropriate. If the decl is 609 // in an outer scope, it isn't the same thing. 610 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 611 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 612 if (NewTD == 0) return 0; 613 } 614 New = NewTD; 615 if (S->getFnParent() == 0) { 616 // C99 6.7.7p2: If a typedef name specifies a variably modified type 617 // then it shall have block scope. 618 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 619 // FIXME: Diagnostic needs to be fixed. 620 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 621 InvalidDecl = true; 622 } 623 } 624 } else if (R.getTypePtr()->isFunctionType()) { 625 FunctionDecl::StorageClass SC = FunctionDecl::None; 626 switch (D.getDeclSpec().getStorageClassSpec()) { 627 default: assert(0 && "Unknown storage class!"); 628 case DeclSpec::SCS_auto: 629 case DeclSpec::SCS_register: 630 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 631 R.getAsString()); 632 InvalidDecl = true; 633 break; 634 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 635 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 636 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 637 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 638 } 639 640 bool isInline = D.getDeclSpec().isInlineSpecified(); 641 FunctionDecl *NewFD; 642 if (D.getContext() == Declarator::MemberContext) { 643 // This is a C++ method declaration. 644 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(CurContext), 645 D.getIdentifierLoc(), II, R, 646 (SC == FunctionDecl::Static), isInline, 647 LastDeclarator); 648 } else { 649 NewFD = FunctionDecl::Create(Context, CurContext, 650 D.getIdentifierLoc(), 651 II, R, SC, isInline, 652 LastDeclarator); 653 } 654 // Handle attributes. 655 ProcessDeclAttributes(NewFD, D); 656 657 // Handle GNU asm-label extension (encoded as an attribute). 658 if (Expr *E = (Expr*) D.getAsmLabel()) { 659 // The parser guarantees this is a string. 660 StringLiteral *SE = cast<StringLiteral>(E); 661 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 662 SE->getByteLength()))); 663 } 664 665 // Copy the parameter declarations from the declarator D to 666 // the function declaration NewFD, if they are available. 667 if (D.getNumTypeObjects() > 0) { 668 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 669 670 // Create Decl objects for each parameter, adding them to the 671 // FunctionDecl. 672 llvm::SmallVector<ParmVarDecl*, 16> Params; 673 674 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 675 // function that takes no arguments, not a function that takes a 676 // single void argument. 677 // We let through "const void" here because Sema::GetTypeForDeclarator 678 // already checks for that case. 679 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 680 FTI.ArgInfo[0].Param && 681 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 682 // empty arg list, don't push any params. 683 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 684 685 // In C++, the empty parameter-type-list must be spelled "void"; a 686 // typedef of void is not permitted. 687 if (getLangOptions().CPlusPlus && 688 Param->getType().getUnqualifiedType() != Context.VoidTy) { 689 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 690 } 691 692 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 693 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 694 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 695 } 696 697 NewFD->setParams(&Params[0], Params.size()); 698 } 699 700 // Merge the decl with the existing one if appropriate. Since C functions 701 // are in a flat namespace, make sure we consider decls in outer scopes. 702 if (PrevDecl && 703 (!getLangOptions().CPlusPlus || 704 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { 705 bool Redeclaration = false; 706 NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); 707 if (NewFD == 0) return 0; 708 if (Redeclaration) { 709 NewFD->setPreviousDeclaration(cast<FunctionDecl>(PrevDecl)); 710 } 711 } 712 New = NewFD; 713 714 // In C++, check default arguments now that we have merged decls. 715 if (getLangOptions().CPlusPlus) 716 CheckCXXDefaultArguments(NewFD); 717 } else { 718 // Check that there are no default arguments (C++ only). 719 if (getLangOptions().CPlusPlus) 720 CheckExtraCXXDefaultArguments(D); 721 722 if (R.getTypePtr()->isObjCInterfaceType()) { 723 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 724 D.getIdentifier()->getName()); 725 InvalidDecl = true; 726 } 727 728 VarDecl *NewVD; 729 VarDecl::StorageClass SC; 730 switch (D.getDeclSpec().getStorageClassSpec()) { 731 default: assert(0 && "Unknown storage class!"); 732 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 733 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 734 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 735 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 736 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 737 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 738 } 739 if (D.getContext() == Declarator::MemberContext) { 740 assert(SC == VarDecl::Static && "Invalid storage class for member!"); 741 // This is a static data member for a C++ class. 742 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(CurContext), 743 D.getIdentifierLoc(), II, 744 R, LastDeclarator); 745 } else { 746 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 747 if (S->getFnParent() == 0) { 748 // C99 6.9p2: The storage-class specifiers auto and register shall not 749 // appear in the declaration specifiers in an external declaration. 750 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 751 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 752 R.getAsString()); 753 InvalidDecl = true; 754 } 755 } 756 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 757 II, R, SC, LastDeclarator); 758 NewVD->setThreadSpecified(ThreadSpecified); 759 } 760 // Handle attributes prior to checking for duplicates in MergeVarDecl 761 ProcessDeclAttributes(NewVD, D); 762 763 // Handle GNU asm-label extension (encoded as an attribute). 764 if (Expr *E = (Expr*) D.getAsmLabel()) { 765 // The parser guarantees this is a string. 766 StringLiteral *SE = cast<StringLiteral>(E); 767 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 768 SE->getByteLength()))); 769 } 770 771 // Emit an error if an address space was applied to decl with local storage. 772 // This includes arrays of objects with address space qualifiers, but not 773 // automatic variables that point to other address spaces. 774 // ISO/IEC TR 18037 S5.1.2 775 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 776 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 777 InvalidDecl = true; 778 } 779 // Merge the decl with the existing one if appropriate. If the decl is 780 // in an outer scope, it isn't the same thing. 781 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 782 NewVD = MergeVarDecl(NewVD, PrevDecl); 783 if (NewVD == 0) return 0; 784 } 785 New = NewVD; 786 } 787 788 // If this has an identifier, add it to the scope stack. 789 if (II) 790 PushOnScopeChains(New, S); 791 // If any semantic error occurred, mark the decl as invalid. 792 if (D.getInvalidType() || InvalidDecl) 793 New->setInvalidDecl(); 794 795 return New; 796} 797 798bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 799 switch (Init->getStmtClass()) { 800 default: 801 Diag(Init->getExprLoc(), 802 diag::err_init_element_not_constant, Init->getSourceRange()); 803 return true; 804 case Expr::ParenExprClass: { 805 const ParenExpr* PE = cast<ParenExpr>(Init); 806 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 807 } 808 case Expr::CompoundLiteralExprClass: 809 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 810 case Expr::DeclRefExprClass: { 811 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 812 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 813 if (VD->hasGlobalStorage()) 814 return false; 815 Diag(Init->getExprLoc(), 816 diag::err_init_element_not_constant, Init->getSourceRange()); 817 return true; 818 } 819 if (isa<FunctionDecl>(D)) 820 return false; 821 Diag(Init->getExprLoc(), 822 diag::err_init_element_not_constant, Init->getSourceRange()); 823 return true; 824 } 825 case Expr::MemberExprClass: { 826 const MemberExpr *M = cast<MemberExpr>(Init); 827 if (M->isArrow()) 828 return CheckAddressConstantExpression(M->getBase()); 829 return CheckAddressConstantExpressionLValue(M->getBase()); 830 } 831 case Expr::ArraySubscriptExprClass: { 832 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 833 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 834 return CheckAddressConstantExpression(ASE->getBase()) || 835 CheckArithmeticConstantExpression(ASE->getIdx()); 836 } 837 case Expr::StringLiteralClass: 838 case Expr::PredefinedExprClass: 839 return false; 840 case Expr::UnaryOperatorClass: { 841 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 842 843 // C99 6.6p9 844 if (Exp->getOpcode() == UnaryOperator::Deref) 845 return CheckAddressConstantExpression(Exp->getSubExpr()); 846 847 Diag(Init->getExprLoc(), 848 diag::err_init_element_not_constant, Init->getSourceRange()); 849 return true; 850 } 851 } 852} 853 854bool Sema::CheckAddressConstantExpression(const Expr* Init) { 855 switch (Init->getStmtClass()) { 856 default: 857 Diag(Init->getExprLoc(), 858 diag::err_init_element_not_constant, Init->getSourceRange()); 859 return true; 860 case Expr::ParenExprClass: { 861 const ParenExpr* PE = cast<ParenExpr>(Init); 862 return CheckAddressConstantExpression(PE->getSubExpr()); 863 } 864 case Expr::StringLiteralClass: 865 case Expr::ObjCStringLiteralClass: 866 return false; 867 case Expr::CallExprClass: { 868 const CallExpr *CE = cast<CallExpr>(Init); 869 if (CE->isBuiltinConstantExpr()) 870 return false; 871 Diag(Init->getExprLoc(), 872 diag::err_init_element_not_constant, Init->getSourceRange()); 873 return true; 874 } 875 case Expr::UnaryOperatorClass: { 876 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 877 878 // C99 6.6p9 879 if (Exp->getOpcode() == UnaryOperator::AddrOf) 880 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 881 882 if (Exp->getOpcode() == UnaryOperator::Extension) 883 return CheckAddressConstantExpression(Exp->getSubExpr()); 884 885 Diag(Init->getExprLoc(), 886 diag::err_init_element_not_constant, Init->getSourceRange()); 887 return true; 888 } 889 case Expr::BinaryOperatorClass: { 890 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 891 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 892 893 Expr *PExp = Exp->getLHS(); 894 Expr *IExp = Exp->getRHS(); 895 if (IExp->getType()->isPointerType()) 896 std::swap(PExp, IExp); 897 898 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 899 return CheckAddressConstantExpression(PExp) || 900 CheckArithmeticConstantExpression(IExp); 901 } 902 case Expr::ImplicitCastExprClass: 903 case Expr::ExplicitCastExprClass: { 904 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 905 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 906 // Check for implicit promotion 907 if (SubExpr->getType()->isFunctionType() || 908 SubExpr->getType()->isArrayType()) 909 return CheckAddressConstantExpressionLValue(SubExpr); 910 } 911 912 // Check for pointer->pointer cast 913 if (SubExpr->getType()->isPointerType()) 914 return CheckAddressConstantExpression(SubExpr); 915 916 if (SubExpr->getType()->isIntegralType()) { 917 // Check for the special-case of a pointer->int->pointer cast; 918 // this isn't standard, but some code requires it. See 919 // PR2720 for an example. 920 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 921 if (SubCast->getSubExpr()->getType()->isPointerType()) { 922 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 923 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 924 if (IntWidth >= PointerWidth) { 925 return CheckAddressConstantExpression(SubCast->getSubExpr()); 926 } 927 } 928 } 929 } 930 if (SubExpr->getType()->isArithmeticType()) { 931 return CheckArithmeticConstantExpression(SubExpr); 932 } 933 934 Diag(Init->getExprLoc(), 935 diag::err_init_element_not_constant, Init->getSourceRange()); 936 return true; 937 } 938 case Expr::ConditionalOperatorClass: { 939 // FIXME: Should we pedwarn here? 940 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 941 if (!Exp->getCond()->getType()->isArithmeticType()) { 942 Diag(Init->getExprLoc(), 943 diag::err_init_element_not_constant, Init->getSourceRange()); 944 return true; 945 } 946 if (CheckArithmeticConstantExpression(Exp->getCond())) 947 return true; 948 if (Exp->getLHS() && 949 CheckAddressConstantExpression(Exp->getLHS())) 950 return true; 951 return CheckAddressConstantExpression(Exp->getRHS()); 952 } 953 case Expr::AddrLabelExprClass: 954 return false; 955 } 956} 957 958static const Expr* FindExpressionBaseAddress(const Expr* E); 959 960static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 961 switch (E->getStmtClass()) { 962 default: 963 return E; 964 case Expr::ParenExprClass: { 965 const ParenExpr* PE = cast<ParenExpr>(E); 966 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 967 } 968 case Expr::MemberExprClass: { 969 const MemberExpr *M = cast<MemberExpr>(E); 970 if (M->isArrow()) 971 return FindExpressionBaseAddress(M->getBase()); 972 return FindExpressionBaseAddressLValue(M->getBase()); 973 } 974 case Expr::ArraySubscriptExprClass: { 975 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 976 return FindExpressionBaseAddress(ASE->getBase()); 977 } 978 case Expr::UnaryOperatorClass: { 979 const UnaryOperator *Exp = cast<UnaryOperator>(E); 980 981 if (Exp->getOpcode() == UnaryOperator::Deref) 982 return FindExpressionBaseAddress(Exp->getSubExpr()); 983 984 return E; 985 } 986 } 987} 988 989static const Expr* FindExpressionBaseAddress(const Expr* E) { 990 switch (E->getStmtClass()) { 991 default: 992 return E; 993 case Expr::ParenExprClass: { 994 const ParenExpr* PE = cast<ParenExpr>(E); 995 return FindExpressionBaseAddress(PE->getSubExpr()); 996 } 997 case Expr::UnaryOperatorClass: { 998 const UnaryOperator *Exp = cast<UnaryOperator>(E); 999 1000 // C99 6.6p9 1001 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1002 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1003 1004 if (Exp->getOpcode() == UnaryOperator::Extension) 1005 return FindExpressionBaseAddress(Exp->getSubExpr()); 1006 1007 return E; 1008 } 1009 case Expr::BinaryOperatorClass: { 1010 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1011 1012 Expr *PExp = Exp->getLHS(); 1013 Expr *IExp = Exp->getRHS(); 1014 if (IExp->getType()->isPointerType()) 1015 std::swap(PExp, IExp); 1016 1017 return FindExpressionBaseAddress(PExp); 1018 } 1019 case Expr::ImplicitCastExprClass: { 1020 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1021 1022 // Check for implicit promotion 1023 if (SubExpr->getType()->isFunctionType() || 1024 SubExpr->getType()->isArrayType()) 1025 return FindExpressionBaseAddressLValue(SubExpr); 1026 1027 // Check for pointer->pointer cast 1028 if (SubExpr->getType()->isPointerType()) 1029 return FindExpressionBaseAddress(SubExpr); 1030 1031 // We assume that we have an arithmetic expression here; 1032 // if we don't, we'll figure it out later 1033 return 0; 1034 } 1035 case Expr::ExplicitCastExprClass: { 1036 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1037 1038 // Check for pointer->pointer cast 1039 if (SubExpr->getType()->isPointerType()) 1040 return FindExpressionBaseAddress(SubExpr); 1041 1042 // We assume that we have an arithmetic expression here; 1043 // if we don't, we'll figure it out later 1044 return 0; 1045 } 1046 } 1047} 1048 1049bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1050 switch (Init->getStmtClass()) { 1051 default: 1052 Diag(Init->getExprLoc(), 1053 diag::err_init_element_not_constant, Init->getSourceRange()); 1054 return true; 1055 case Expr::ParenExprClass: { 1056 const ParenExpr* PE = cast<ParenExpr>(Init); 1057 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1058 } 1059 case Expr::FloatingLiteralClass: 1060 case Expr::IntegerLiteralClass: 1061 case Expr::CharacterLiteralClass: 1062 case Expr::ImaginaryLiteralClass: 1063 case Expr::TypesCompatibleExprClass: 1064 case Expr::CXXBoolLiteralExprClass: 1065 return false; 1066 case Expr::CallExprClass: { 1067 const CallExpr *CE = cast<CallExpr>(Init); 1068 if (CE->isBuiltinConstantExpr()) 1069 return false; 1070 Diag(Init->getExprLoc(), 1071 diag::err_init_element_not_constant, Init->getSourceRange()); 1072 return true; 1073 } 1074 case Expr::DeclRefExprClass: { 1075 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1076 if (isa<EnumConstantDecl>(D)) 1077 return false; 1078 Diag(Init->getExprLoc(), 1079 diag::err_init_element_not_constant, Init->getSourceRange()); 1080 return true; 1081 } 1082 case Expr::CompoundLiteralExprClass: 1083 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1084 // but vectors are allowed to be magic. 1085 if (Init->getType()->isVectorType()) 1086 return false; 1087 Diag(Init->getExprLoc(), 1088 diag::err_init_element_not_constant, Init->getSourceRange()); 1089 return true; 1090 case Expr::UnaryOperatorClass: { 1091 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1092 1093 switch (Exp->getOpcode()) { 1094 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1095 // See C99 6.6p3. 1096 default: 1097 Diag(Init->getExprLoc(), 1098 diag::err_init_element_not_constant, Init->getSourceRange()); 1099 return true; 1100 case UnaryOperator::SizeOf: 1101 case UnaryOperator::AlignOf: 1102 case UnaryOperator::OffsetOf: 1103 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1104 // See C99 6.5.3.4p2 and 6.6p3. 1105 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1106 return false; 1107 Diag(Init->getExprLoc(), 1108 diag::err_init_element_not_constant, Init->getSourceRange()); 1109 return true; 1110 case UnaryOperator::Extension: 1111 case UnaryOperator::LNot: 1112 case UnaryOperator::Plus: 1113 case UnaryOperator::Minus: 1114 case UnaryOperator::Not: 1115 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1116 } 1117 } 1118 case Expr::SizeOfAlignOfTypeExprClass: { 1119 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1120 // Special check for void types, which are allowed as an extension 1121 if (Exp->getArgumentType()->isVoidType()) 1122 return false; 1123 // alignof always evaluates to a constant. 1124 // FIXME: is sizeof(int[3.0]) a constant expression? 1125 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1126 Diag(Init->getExprLoc(), 1127 diag::err_init_element_not_constant, Init->getSourceRange()); 1128 return true; 1129 } 1130 return false; 1131 } 1132 case Expr::BinaryOperatorClass: { 1133 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1134 1135 if (Exp->getLHS()->getType()->isArithmeticType() && 1136 Exp->getRHS()->getType()->isArithmeticType()) { 1137 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1138 CheckArithmeticConstantExpression(Exp->getRHS()); 1139 } 1140 1141 if (Exp->getLHS()->getType()->isPointerType() && 1142 Exp->getRHS()->getType()->isPointerType()) { 1143 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1144 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1145 1146 // Only allow a null (constant integer) base; we could 1147 // allow some additional cases if necessary, but this 1148 // is sufficient to cover offsetof-like constructs. 1149 if (!LHSBase && !RHSBase) { 1150 return CheckAddressConstantExpression(Exp->getLHS()) || 1151 CheckAddressConstantExpression(Exp->getRHS()); 1152 } 1153 } 1154 1155 Diag(Init->getExprLoc(), 1156 diag::err_init_element_not_constant, Init->getSourceRange()); 1157 return true; 1158 } 1159 case Expr::ImplicitCastExprClass: 1160 case Expr::ExplicitCastExprClass: { 1161 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1162 if (SubExpr->getType()->isArithmeticType()) 1163 return CheckArithmeticConstantExpression(SubExpr); 1164 1165 if (SubExpr->getType()->isPointerType()) { 1166 const Expr* Base = FindExpressionBaseAddress(SubExpr); 1167 // If the pointer has a null base, this is an offsetof-like construct 1168 if (!Base) 1169 return CheckAddressConstantExpression(SubExpr); 1170 } 1171 1172 Diag(Init->getExprLoc(), 1173 diag::err_init_element_not_constant, Init->getSourceRange()); 1174 return true; 1175 } 1176 case Expr::ConditionalOperatorClass: { 1177 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1178 if (CheckArithmeticConstantExpression(Exp->getCond())) 1179 return true; 1180 if (Exp->getLHS() && 1181 CheckArithmeticConstantExpression(Exp->getLHS())) 1182 return true; 1183 return CheckArithmeticConstantExpression(Exp->getRHS()); 1184 } 1185 } 1186} 1187 1188bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1189 Init = Init->IgnoreParens(); 1190 1191 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1192 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1193 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1194 1195 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 1196 return CheckForConstantInitializer(e->getInitializer(), DclT); 1197 1198 if (Init->getType()->isReferenceType()) { 1199 // FIXME: Work out how the heck reference types work 1200 return false; 1201#if 0 1202 // A reference is constant if the address of the expression 1203 // is constant 1204 // We look through initlists here to simplify 1205 // CheckAddressConstantExpressionLValue. 1206 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1207 assert(Exp->getNumInits() > 0 && 1208 "Refernce initializer cannot be empty"); 1209 Init = Exp->getInit(0); 1210 } 1211 return CheckAddressConstantExpressionLValue(Init); 1212#endif 1213 } 1214 1215 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1216 unsigned numInits = Exp->getNumInits(); 1217 for (unsigned i = 0; i < numInits; i++) { 1218 // FIXME: Need to get the type of the declaration for C++, 1219 // because it could be a reference? 1220 if (CheckForConstantInitializer(Exp->getInit(i), 1221 Exp->getInit(i)->getType())) 1222 return true; 1223 } 1224 return false; 1225 } 1226 1227 if (Init->isNullPointerConstant(Context)) 1228 return false; 1229 if (Init->getType()->isArithmeticType()) { 1230 QualType InitTy = Context.getCanonicalType(Init->getType()) 1231 .getUnqualifiedType(); 1232 if (InitTy == Context.BoolTy) { 1233 // Special handling for pointers implicitly cast to bool; 1234 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1235 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1236 Expr* SubE = ICE->getSubExpr(); 1237 if (SubE->getType()->isPointerType() || 1238 SubE->getType()->isArrayType() || 1239 SubE->getType()->isFunctionType()) { 1240 return CheckAddressConstantExpression(Init); 1241 } 1242 } 1243 } else if (InitTy->isIntegralType()) { 1244 Expr* SubE = 0; 1245 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1246 SubE = CE->getSubExpr(); 1247 // Special check for pointer cast to int; we allow as an extension 1248 // an address constant cast to an integer if the integer 1249 // is of an appropriate width (this sort of code is apparently used 1250 // in some places). 1251 // FIXME: Add pedwarn? 1252 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1253 if (SubE && (SubE->getType()->isPointerType() || 1254 SubE->getType()->isArrayType() || 1255 SubE->getType()->isFunctionType())) { 1256 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1257 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1258 if (IntWidth >= PointerWidth) 1259 return CheckAddressConstantExpression(Init); 1260 } 1261 } 1262 1263 return CheckArithmeticConstantExpression(Init); 1264 } 1265 1266 if (Init->getType()->isPointerType()) 1267 return CheckAddressConstantExpression(Init); 1268 1269 // An array type at the top level that isn't an init-list must 1270 // be a string literal 1271 if (Init->getType()->isArrayType()) 1272 return false; 1273 1274 if (Init->getType()->isFunctionType()) 1275 return false; 1276 1277 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1278 Init->getSourceRange()); 1279 return true; 1280} 1281 1282void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1283 Decl *RealDecl = static_cast<Decl *>(dcl); 1284 Expr *Init = static_cast<Expr *>(init); 1285 assert(Init && "missing initializer"); 1286 1287 // If there is no declaration, there was an error parsing it. Just ignore 1288 // the initializer. 1289 if (RealDecl == 0) { 1290 delete Init; 1291 return; 1292 } 1293 1294 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1295 if (!VDecl) { 1296 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1297 diag::err_illegal_initializer); 1298 RealDecl->setInvalidDecl(); 1299 return; 1300 } 1301 // Get the decls type and save a reference for later, since 1302 // CheckInitializerTypes may change it. 1303 QualType DclT = VDecl->getType(), SavT = DclT; 1304 if (VDecl->isBlockVarDecl()) { 1305 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1306 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1307 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1308 VDecl->setInvalidDecl(); 1309 } else if (!VDecl->isInvalidDecl()) { 1310 if (CheckInitializerTypes(Init, DclT)) 1311 VDecl->setInvalidDecl(); 1312 1313 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 1314 if (!getLangOptions().CPlusPlus) { 1315 if (SC == VarDecl::Static) // C99 6.7.8p4. 1316 CheckForConstantInitializer(Init, DclT); 1317 } 1318 } 1319 } else if (VDecl->isFileVarDecl()) { 1320 if (VDecl->getStorageClass() == VarDecl::Extern) 1321 Diag(VDecl->getLocation(), diag::warn_extern_init); 1322 if (!VDecl->isInvalidDecl()) 1323 if (CheckInitializerTypes(Init, DclT)) 1324 VDecl->setInvalidDecl(); 1325 1326 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 1327 if (!getLangOptions().CPlusPlus) { 1328 // C99 6.7.8p4. All file scoped initializers need to be constant. 1329 CheckForConstantInitializer(Init, DclT); 1330 } 1331 } 1332 // If the type changed, it means we had an incomplete type that was 1333 // completed by the initializer. For example: 1334 // int ary[] = { 1, 3, 5 }; 1335 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1336 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1337 VDecl->setType(DclT); 1338 Init->setType(DclT); 1339 } 1340 1341 // Attach the initializer to the decl. 1342 VDecl->setInit(Init); 1343 return; 1344} 1345 1346/// The declarators are chained together backwards, reverse the list. 1347Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1348 // Often we have single declarators, handle them quickly. 1349 Decl *GroupDecl = static_cast<Decl*>(group); 1350 if (GroupDecl == 0) 1351 return 0; 1352 1353 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1354 ScopedDecl *NewGroup = 0; 1355 if (Group->getNextDeclarator() == 0) 1356 NewGroup = Group; 1357 else { // reverse the list. 1358 while (Group) { 1359 ScopedDecl *Next = Group->getNextDeclarator(); 1360 Group->setNextDeclarator(NewGroup); 1361 NewGroup = Group; 1362 Group = Next; 1363 } 1364 } 1365 // Perform semantic analysis that depends on having fully processed both 1366 // the declarator and initializer. 1367 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1368 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1369 if (!IDecl) 1370 continue; 1371 QualType T = IDecl->getType(); 1372 1373 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1374 // static storage duration, it shall not have a variable length array. 1375 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1376 IDecl->getStorageClass() == VarDecl::Static) { 1377 if (T->isVariableArrayType()) { 1378 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1379 IDecl->setInvalidDecl(); 1380 } 1381 } 1382 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1383 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1384 if (IDecl->isBlockVarDecl() && 1385 IDecl->getStorageClass() != VarDecl::Extern) { 1386 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1387 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1388 T.getAsString()); 1389 IDecl->setInvalidDecl(); 1390 } 1391 } 1392 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1393 // object that has file scope without an initializer, and without a 1394 // storage-class specifier or with the storage-class specifier "static", 1395 // constitutes a tentative definition. Note: A tentative definition with 1396 // external linkage is valid (C99 6.2.2p5). 1397 if (isTentativeDefinition(IDecl)) { 1398 if (T->isIncompleteArrayType()) { 1399 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1400 // array to be completed. Don't issue a diagnostic. 1401 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1402 // C99 6.9.2p3: If the declaration of an identifier for an object is 1403 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1404 // declared type shall not be an incomplete type. 1405 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1406 T.getAsString()); 1407 IDecl->setInvalidDecl(); 1408 } 1409 } 1410 if (IDecl->isFileVarDecl()) 1411 CheckForFileScopedRedefinitions(S, IDecl); 1412 } 1413 return NewGroup; 1414} 1415 1416/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1417/// to introduce parameters into function prototype scope. 1418Sema::DeclTy * 1419Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1420 const DeclSpec &DS = D.getDeclSpec(); 1421 1422 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1423 VarDecl::StorageClass StorageClass = VarDecl::None; 1424 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 1425 StorageClass = VarDecl::Register; 1426 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 1427 Diag(DS.getStorageClassSpecLoc(), 1428 diag::err_invalid_storage_class_in_func_decl); 1429 D.getMutableDeclSpec().ClearStorageClassSpecs(); 1430 } 1431 if (DS.isThreadSpecified()) { 1432 Diag(DS.getThreadSpecLoc(), 1433 diag::err_invalid_storage_class_in_func_decl); 1434 D.getMutableDeclSpec().ClearStorageClassSpecs(); 1435 } 1436 1437 // Check that there are no default arguments inside the type of this 1438 // parameter (C++ only). 1439 if (getLangOptions().CPlusPlus) 1440 CheckExtraCXXDefaultArguments(D); 1441 1442 // In this context, we *do not* check D.getInvalidType(). If the declarator 1443 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1444 // though it will not reflect the user specified type. 1445 QualType parmDeclType = GetTypeForDeclarator(D, S); 1446 1447 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1448 1449 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1450 // Can this happen for params? We already checked that they don't conflict 1451 // among each other. Here they can only shadow globals, which is ok. 1452 IdentifierInfo *II = D.getIdentifier(); 1453 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1454 if (S->isDeclScope(PrevDecl)) { 1455 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1456 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1457 1458 // Recover by removing the name 1459 II = 0; 1460 D.SetIdentifier(0, D.getIdentifierLoc()); 1461 } 1462 } 1463 1464 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1465 // Doing the promotion here has a win and a loss. The win is the type for 1466 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1467 // code generator). The loss is the orginal type isn't preserved. For example: 1468 // 1469 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1470 // int blockvardecl[5]; 1471 // sizeof(parmvardecl); // size == 4 1472 // sizeof(blockvardecl); // size == 20 1473 // } 1474 // 1475 // For expressions, all implicit conversions are captured using the 1476 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1477 // 1478 // FIXME: If a source translation tool needs to see the original type, then 1479 // we need to consider storing both types (in ParmVarDecl)... 1480 // 1481 if (parmDeclType->isArrayType()) { 1482 // int x[restrict 4] -> int *restrict 1483 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1484 } else if (parmDeclType->isFunctionType()) 1485 parmDeclType = Context.getPointerType(parmDeclType); 1486 1487 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1488 D.getIdentifierLoc(), II, 1489 parmDeclType, StorageClass, 1490 0, 0); 1491 1492 if (D.getInvalidType()) 1493 New->setInvalidDecl(); 1494 1495 if (II) 1496 PushOnScopeChains(New, S); 1497 1498 ProcessDeclAttributes(New, D); 1499 return New; 1500 1501} 1502 1503Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1504 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 1505 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1506 "Not a function declarator!"); 1507 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1508 1509 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1510 // for a K&R function. 1511 if (!FTI.hasPrototype) { 1512 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1513 if (FTI.ArgInfo[i].Param == 0) { 1514 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1515 FTI.ArgInfo[i].Ident->getName()); 1516 // Implicitly declare the argument as type 'int' for lack of a better 1517 // type. 1518 DeclSpec DS; 1519 const char* PrevSpec; // unused 1520 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1521 PrevSpec); 1522 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1523 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1524 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1525 } 1526 } 1527 } else { 1528 // FIXME: Diagnose arguments without names in C. 1529 } 1530 1531 Scope *GlobalScope = FnBodyScope->getParent(); 1532 1533 // See if this is a redefinition. 1534 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1535 GlobalScope); 1536 if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { 1537 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1538 const FunctionDecl *Definition; 1539 if (FD->getBody(Definition)) { 1540 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1541 D.getIdentifier()->getName()); 1542 Diag(Definition->getLocation(), diag::err_previous_definition); 1543 } 1544 } 1545 } 1546 1547 return ActOnStartOfFunctionDef(FnBodyScope, 1548 ActOnDeclarator(GlobalScope, D, 0)); 1549} 1550 1551Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 1552 Decl *decl = static_cast<Decl*>(D); 1553 FunctionDecl *FD = cast<FunctionDecl>(decl); 1554 PushDeclContext(FD); 1555 1556 // Check the validity of our function parameters 1557 CheckParmsForFunctionDef(FD); 1558 1559 // Introduce our parameters into the function scope 1560 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1561 ParmVarDecl *Param = FD->getParamDecl(p); 1562 // If this has an identifier, add it to the scope stack. 1563 if (Param->getIdentifier()) 1564 PushOnScopeChains(Param, FnBodyScope); 1565 } 1566 1567 return FD; 1568} 1569 1570Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1571 Decl *dcl = static_cast<Decl *>(D); 1572 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 1573 FD->setBody((Stmt*)Body); 1574 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 1575 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 1576 MD->setBody((Stmt*)Body); 1577 } else 1578 return 0; 1579 PopDeclContext(); 1580 // Verify and clean out per-function state. 1581 1582 // Check goto/label use. 1583 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1584 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1585 // Verify that we have no forward references left. If so, there was a goto 1586 // or address of a label taken, but no definition of it. Label fwd 1587 // definitions are indicated with a null substmt. 1588 if (I->second->getSubStmt() == 0) { 1589 LabelStmt *L = I->second; 1590 // Emit error. 1591 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1592 1593 // At this point, we have gotos that use the bogus label. Stitch it into 1594 // the function body so that they aren't leaked and that the AST is well 1595 // formed. 1596 if (Body) { 1597 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1598 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1599 } else { 1600 // The whole function wasn't parsed correctly, just delete this. 1601 delete L; 1602 } 1603 } 1604 } 1605 LabelMap.clear(); 1606 1607 return D; 1608} 1609 1610/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1611/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1612ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1613 IdentifierInfo &II, Scope *S) { 1614 // Extension in C99. Legal in C90, but warn about it. 1615 if (getLangOptions().C99) 1616 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1617 else 1618 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1619 1620 // FIXME: handle stuff like: 1621 // void foo() { extern float X(); } 1622 // void bar() { X(); } <-- implicit decl for X in another scope. 1623 1624 // Set a Declarator for the implicit definition: int foo(); 1625 const char *Dummy; 1626 DeclSpec DS; 1627 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1628 Error = Error; // Silence warning. 1629 assert(!Error && "Error setting up implicit decl!"); 1630 Declarator D(DS, Declarator::BlockContext); 1631 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1632 D.SetIdentifier(&II, Loc); 1633 1634 // Insert this function into translation-unit scope. 1635 1636 DeclContext *PrevDC = CurContext; 1637 CurContext = Context.getTranslationUnitDecl(); 1638 1639 FunctionDecl *FD = 1640 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1641 FD->setImplicit(); 1642 1643 CurContext = PrevDC; 1644 1645 return FD; 1646} 1647 1648 1649TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1650 ScopedDecl *LastDeclarator) { 1651 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1652 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1653 1654 // Scope manipulation handled by caller. 1655 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1656 D.getIdentifierLoc(), 1657 D.getIdentifier(), 1658 T, LastDeclarator); 1659 if (D.getInvalidType()) 1660 NewTD->setInvalidDecl(); 1661 return NewTD; 1662} 1663 1664/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1665/// former case, Name will be non-null. In the later case, Name will be null. 1666/// TagType indicates what kind of tag this is. TK indicates whether this is a 1667/// reference/declaration/definition of a tag. 1668Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1669 SourceLocation KWLoc, IdentifierInfo *Name, 1670 SourceLocation NameLoc, AttributeList *Attr) { 1671 // If this is a use of an existing tag, it must have a name. 1672 assert((Name != 0 || TK == TK_Definition) && 1673 "Nameless record must be a definition!"); 1674 1675 TagDecl::TagKind Kind; 1676 switch (TagType) { 1677 default: assert(0 && "Unknown tag type!"); 1678 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 1679 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 1680 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 1681 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 1682 } 1683 1684 // Two code paths: a new one for structs/unions/classes where we create 1685 // separate decls for forward declarations, and an old (eventually to 1686 // be removed) code path for enums. 1687 if (Kind != TagDecl::TK_enum) 1688 return ActOnTagStruct(S, Kind, TK, KWLoc, Name, NameLoc, Attr); 1689 1690 // If this is a named struct, check to see if there was a previous forward 1691 // declaration or definition. 1692 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1693 ScopedDecl *PrevDecl = 1694 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S)); 1695 1696 if (PrevDecl) { 1697 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1698 "unexpected Decl type"); 1699 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1700 // If this is a use of a previous tag, or if the tag is already declared 1701 // in the same scope (so that the definition/declaration completes or 1702 // rementions the tag), reuse the decl. 1703 if (TK == TK_Reference || 1704 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1705 // Make sure that this wasn't declared as an enum and now used as a 1706 // struct or something similar. 1707 if (PrevTagDecl->getTagKind() != Kind) { 1708 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1709 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1710 // Recover by making this an anonymous redefinition. 1711 Name = 0; 1712 PrevDecl = 0; 1713 } else { 1714 // If this is a use or a forward declaration, we're good. 1715 if (TK != TK_Definition) 1716 return PrevDecl; 1717 1718 // Diagnose attempts to redefine a tag. 1719 if (PrevTagDecl->isDefinition()) { 1720 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1721 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1722 // If this is a redefinition, recover by making this struct be 1723 // anonymous, which will make any later references get the previous 1724 // definition. 1725 Name = 0; 1726 } else { 1727 // Okay, this is definition of a previously declared or referenced 1728 // tag. Move the location of the decl to be the definition site. 1729 PrevDecl->setLocation(NameLoc); 1730 return PrevDecl; 1731 } 1732 } 1733 } 1734 // If we get here, this is a definition of a new struct type in a nested 1735 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1736 // type. 1737 } else { 1738 // PrevDecl is a namespace. 1739 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1740 // The tag name clashes with a namespace name, issue an error and 1741 // recover by making this tag be anonymous. 1742 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1743 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1744 Name = 0; 1745 } 1746 } 1747 } 1748 1749 // If there is an identifier, use the location of the identifier as the 1750 // location of the decl, otherwise use the location of the struct/union 1751 // keyword. 1752 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1753 1754 // Otherwise, if this is the first time we've seen this tag, create the decl. 1755 TagDecl *New; 1756 if (Kind == TagDecl::TK_enum) { 1757 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1758 // enum X { A, B, C } D; D should chain to X. 1759 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1760 // If this is an undefined enum, warn. 1761 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1762 } else { 1763 // struct/union/class 1764 1765 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1766 // struct X { int A; } D; D should chain to X. 1767 if (getLangOptions().CPlusPlus) 1768 // FIXME: Look for a way to use RecordDecl for simple structs. 1769 New = CXXRecordDecl::Create(Context, Kind, CurContext, Loc, Name); 1770 else 1771 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name); 1772 } 1773 1774 // If this has an identifier, add it to the scope stack. 1775 if (Name) { 1776 // The scope passed in may not be a decl scope. Zip up the scope tree until 1777 // we find one that is. 1778 while ((S->getFlags() & Scope::DeclScope) == 0) 1779 S = S->getParent(); 1780 1781 // Add it to the decl chain. 1782 PushOnScopeChains(New, S); 1783 } 1784 1785 if (Attr) 1786 ProcessDeclAttributeList(New, Attr); 1787 return New; 1788} 1789 1790/// ActOnTagStruct - New "ActOnTag" logic for structs/unions/classes. Unlike 1791/// the logic for enums, we create separate decls for forward declarations. 1792/// This is called by ActOnTag, but eventually will replace its logic. 1793Sema::DeclTy *Sema::ActOnTagStruct(Scope *S, TagDecl::TagKind Kind, TagKind TK, 1794 SourceLocation KWLoc, IdentifierInfo *Name, 1795 SourceLocation NameLoc, AttributeList *Attr) { 1796 1797 // If this is a named struct, check to see if there was a previous forward 1798 // declaration or definition. 1799 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1800 ScopedDecl *PrevDecl = 1801 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S)); 1802 1803 if (PrevDecl) { 1804 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1805 "unexpected Decl type"); 1806 1807 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1808 // If this is a use of a previous tag, or if the tag is already declared 1809 // in the same scope (so that the definition/declaration completes or 1810 // rementions the tag), reuse the decl. 1811 if (TK == TK_Reference || 1812 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1813 // Make sure that this wasn't declared as an enum and now used as a 1814 // struct or something similar. 1815 if (PrevTagDecl->getTagKind() != Kind) { 1816 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1817 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1818 // Recover by making this an anonymous redefinition. 1819 Name = 0; 1820 PrevDecl = 0; 1821 } else { 1822 // If this is a use, return the original decl. 1823 1824 // FIXME: In the future, return a variant or some other clue 1825 // for the consumer of this Decl to know it doesn't own it. 1826 // For our current ASTs this shouldn't be a problem, but will 1827 // need to be changed with DeclGroups. 1828 if (TK == TK_Reference) 1829 return PrevDecl; 1830 1831 // The new decl is a definition? 1832 if (TK == TK_Definition) { 1833 // Diagnose attempts to redefine a tag. 1834 if (RecordDecl* DefRecord = 1835 cast<RecordDecl>(PrevTagDecl)->getDefinition(Context)) { 1836 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1837 Diag(DefRecord->getLocation(), diag::err_previous_definition); 1838 // If this is a redefinition, recover by making this struct be 1839 // anonymous, which will make any later references get the previous 1840 // definition. 1841 Name = 0; 1842 PrevDecl = 0; 1843 } 1844 // Okay, this is definition of a previously declared or referenced 1845 // tag. We're going to create a new Decl. 1846 } 1847 } 1848 // If we get here we have (another) forward declaration. Just create 1849 // a new decl. 1850 } 1851 else { 1852 // If we get here, this is a definition of a new struct type in a nested 1853 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 1854 // new decl/type. We set PrevDecl to NULL so that the Records 1855 // have distinct types. 1856 PrevDecl = 0; 1857 } 1858 } else { 1859 // PrevDecl is a namespace. 1860 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1861 // The tag name clashes with a namespace name, issue an error and 1862 // recover by making this tag be anonymous. 1863 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1864 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1865 Name = 0; 1866 } 1867 } 1868 } 1869 1870 // If there is an identifier, use the location of the identifier as the 1871 // location of the decl, otherwise use the location of the struct/union 1872 // keyword. 1873 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1874 1875 // Otherwise, if this is the first time we've seen this tag, create the decl. 1876 TagDecl *New; 1877 1878 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1879 // struct X { int A; } D; D should chain to X. 1880 if (getLangOptions().CPlusPlus) 1881 // FIXME: Look for a way to use RecordDecl for simple structs. 1882 New = CXXRecordDecl::Create(Context, Kind, CurContext, Loc, Name, 1883 dyn_cast_or_null<CXXRecordDecl>(PrevDecl)); 1884 else 1885 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 1886 dyn_cast_or_null<RecordDecl>(PrevDecl)); 1887 1888 // If this has an identifier, add it to the scope stack. 1889 if ((TK == TK_Definition || !PrevDecl) && Name) { 1890 // The scope passed in may not be a decl scope. Zip up the scope tree until 1891 // we find one that is. 1892 while ((S->getFlags() & Scope::DeclScope) == 0) 1893 S = S->getParent(); 1894 1895 // Add it to the decl chain. 1896 PushOnScopeChains(New, S); 1897 } 1898 1899 if (Attr) 1900 ProcessDeclAttributeList(New, Attr); 1901 1902 return New; 1903} 1904 1905 1906/// Collect the instance variables declared in an Objective-C object. Used in 1907/// the creation of structures from objects using the @defs directive. 1908static void CollectIvars(ObjCInterfaceDecl *Class, ASTContext& Ctx, 1909 llvm::SmallVectorImpl<Sema::DeclTy*> &ivars) { 1910 if (Class->getSuperClass()) 1911 CollectIvars(Class->getSuperClass(), Ctx, ivars); 1912 1913 // For each ivar, create a fresh ObjCAtDefsFieldDecl. 1914 for (ObjCInterfaceDecl::ivar_iterator 1915 I=Class->ivar_begin(), E=Class->ivar_end(); I!=E; ++I) { 1916 1917 ObjCIvarDecl* ID = *I; 1918 ivars.push_back(ObjCAtDefsFieldDecl::Create(Ctx, ID->getLocation(), 1919 ID->getIdentifier(), 1920 ID->getType(), 1921 ID->getBitWidth())); 1922 } 1923} 1924 1925/// Called whenever @defs(ClassName) is encountered in the source. Inserts the 1926/// instance variables of ClassName into Decls. 1927void Sema::ActOnDefs(Scope *S, SourceLocation DeclStart, 1928 IdentifierInfo *ClassName, 1929 llvm::SmallVectorImpl<DeclTy*> &Decls) { 1930 // Check that ClassName is a valid class 1931 ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName); 1932 if (!Class) { 1933 Diag(DeclStart, diag::err_undef_interface, ClassName->getName()); 1934 return; 1935 } 1936 // Collect the instance variables 1937 CollectIvars(Class, Context, Decls); 1938} 1939 1940QualType Sema::TryFixInvalidVariablyModifiedType(QualType T) { 1941 // This method tries to turn a variable array into a constant 1942 // array even when the size isn't an ICE. This is necessary 1943 // for compatibility with code that depends on gcc's buggy 1944 // constant expression folding, like struct {char x[(int)(char*)2];} 1945 if (const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T)) { 1946 APValue Result; 1947 if (VLATy->getSizeExpr() && 1948 VLATy->getSizeExpr()->tryEvaluate(Result, Context) && Result.isInt()) { 1949 llvm::APSInt &Res = Result.getInt(); 1950 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1951 return Context.getConstantArrayType(VLATy->getElementType(), 1952 Res, ArrayType::Normal, 0); 1953 } 1954 } 1955 return QualType(); 1956} 1957 1958/// ActOnField - Each field of a struct/union/class is passed into this in order 1959/// to create a FieldDecl object for it. 1960Sema::DeclTy *Sema::ActOnField(Scope *S, 1961 SourceLocation DeclStart, 1962 Declarator &D, ExprTy *BitfieldWidth) { 1963 IdentifierInfo *II = D.getIdentifier(); 1964 Expr *BitWidth = (Expr*)BitfieldWidth; 1965 SourceLocation Loc = DeclStart; 1966 if (II) Loc = D.getIdentifierLoc(); 1967 1968 // FIXME: Unnamed fields can be handled in various different ways, for 1969 // example, unnamed unions inject all members into the struct namespace! 1970 1971 if (BitWidth) { 1972 // TODO: Validate. 1973 //printf("WARNING: BITFIELDS IGNORED!\n"); 1974 1975 // 6.7.2.1p3 1976 // 6.7.2.1p4 1977 1978 } else { 1979 // Not a bitfield. 1980 1981 // validate II. 1982 1983 } 1984 1985 QualType T = GetTypeForDeclarator(D, S); 1986 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1987 bool InvalidDecl = false; 1988 1989 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1990 // than a variably modified type. 1991 if (T->isVariablyModifiedType()) { 1992 QualType FixedTy = TryFixInvalidVariablyModifiedType(T); 1993 if (!FixedTy.isNull()) { 1994 Diag(Loc, diag::warn_illegal_constant_array_size, Loc); 1995 T = FixedTy; 1996 } else { 1997 // FIXME: This diagnostic needs work 1998 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1999 InvalidDecl = true; 2000 } 2001 } 2002 // FIXME: Chain fielddecls together. 2003 FieldDecl *NewFD; 2004 2005 if (getLangOptions().CPlusPlus) { 2006 // FIXME: Replace CXXFieldDecls with FieldDecls for simple structs. 2007 NewFD = CXXFieldDecl::Create(Context, cast<CXXRecordDecl>(CurContext), 2008 Loc, II, T, BitWidth); 2009 if (II) 2010 PushOnScopeChains(NewFD, S); 2011 } 2012 else 2013 NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 2014 2015 ProcessDeclAttributes(NewFD, D); 2016 2017 if (D.getInvalidType() || InvalidDecl) 2018 NewFD->setInvalidDecl(); 2019 return NewFD; 2020} 2021 2022/// TranslateIvarVisibility - Translate visibility from a token ID to an 2023/// AST enum value. 2024static ObjCIvarDecl::AccessControl 2025TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 2026 switch (ivarVisibility) { 2027 case tok::objc_private: return ObjCIvarDecl::Private; 2028 case tok::objc_public: return ObjCIvarDecl::Public; 2029 case tok::objc_protected: return ObjCIvarDecl::Protected; 2030 case tok::objc_package: return ObjCIvarDecl::Package; 2031 default: assert(false && "Unknown visitibility kind"); 2032 } 2033} 2034 2035/// ActOnIvar - Each ivar field of an objective-c class is passed into this 2036/// in order to create an IvarDecl object for it. 2037Sema::DeclTy *Sema::ActOnIvar(Scope *S, 2038 SourceLocation DeclStart, 2039 Declarator &D, ExprTy *BitfieldWidth, 2040 tok::ObjCKeywordKind Visibility) { 2041 IdentifierInfo *II = D.getIdentifier(); 2042 Expr *BitWidth = (Expr*)BitfieldWidth; 2043 SourceLocation Loc = DeclStart; 2044 if (II) Loc = D.getIdentifierLoc(); 2045 2046 // FIXME: Unnamed fields can be handled in various different ways, for 2047 // example, unnamed unions inject all members into the struct namespace! 2048 2049 2050 if (BitWidth) { 2051 // TODO: Validate. 2052 //printf("WARNING: BITFIELDS IGNORED!\n"); 2053 2054 // 6.7.2.1p3 2055 // 6.7.2.1p4 2056 2057 } else { 2058 // Not a bitfield. 2059 2060 // validate II. 2061 2062 } 2063 2064 QualType T = GetTypeForDeclarator(D, S); 2065 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2066 bool InvalidDecl = false; 2067 2068 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2069 // than a variably modified type. 2070 if (T->isVariablyModifiedType()) { 2071 // FIXME: This diagnostic needs work 2072 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 2073 InvalidDecl = true; 2074 } 2075 2076 // Get the visibility (access control) for this ivar. 2077 ObjCIvarDecl::AccessControl ac = 2078 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 2079 : ObjCIvarDecl::None; 2080 2081 // Construct the decl. 2082 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 2083 (Expr *)BitfieldWidth); 2084 2085 // Process attributes attached to the ivar. 2086 ProcessDeclAttributes(NewID, D); 2087 2088 if (D.getInvalidType() || InvalidDecl) 2089 NewID->setInvalidDecl(); 2090 2091 return NewID; 2092} 2093 2094void Sema::ActOnFields(Scope* S, 2095 SourceLocation RecLoc, DeclTy *RecDecl, 2096 DeclTy **Fields, unsigned NumFields, 2097 SourceLocation LBrac, SourceLocation RBrac) { 2098 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 2099 assert(EnclosingDecl && "missing record or interface decl"); 2100 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 2101 2102 if (Record) 2103 if (RecordDecl* DefRecord = Record->getDefinition(Context)) { 2104 // Diagnose code like: 2105 // struct S { struct S {} X; }; 2106 // We discover this when we complete the outer S. Reject and ignore the 2107 // outer S. 2108 Diag(DefRecord->getLocation(), diag::err_nested_redefinition, 2109 DefRecord->getKindName()); 2110 Diag(RecLoc, diag::err_previous_definition); 2111 Record->setInvalidDecl(); 2112 return; 2113 } 2114 2115 // Verify that all the fields are okay. 2116 unsigned NumNamedMembers = 0; 2117 llvm::SmallVector<FieldDecl*, 32> RecFields; 2118 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 2119 2120 for (unsigned i = 0; i != NumFields; ++i) { 2121 2122 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 2123 assert(FD && "missing field decl"); 2124 2125 // Remember all fields. 2126 RecFields.push_back(FD); 2127 2128 // Get the type for the field. 2129 Type *FDTy = FD->getType().getTypePtr(); 2130 2131 // C99 6.7.2.1p2 - A field may not be a function type. 2132 if (FDTy->isFunctionType()) { 2133 Diag(FD->getLocation(), diag::err_field_declared_as_function, 2134 FD->getName()); 2135 FD->setInvalidDecl(); 2136 EnclosingDecl->setInvalidDecl(); 2137 continue; 2138 } 2139 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 2140 if (FDTy->isIncompleteType()) { 2141 if (!Record) { // Incomplete ivar type is always an error. 2142 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2143 FD->setInvalidDecl(); 2144 EnclosingDecl->setInvalidDecl(); 2145 continue; 2146 } 2147 if (i != NumFields-1 || // ... that the last member ... 2148 !Record->isStruct() || // ... of a structure ... 2149 !FDTy->isArrayType()) { //... may have incomplete array type. 2150 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2151 FD->setInvalidDecl(); 2152 EnclosingDecl->setInvalidDecl(); 2153 continue; 2154 } 2155 if (NumNamedMembers < 1) { //... must have more than named member ... 2156 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 2157 FD->getName()); 2158 FD->setInvalidDecl(); 2159 EnclosingDecl->setInvalidDecl(); 2160 continue; 2161 } 2162 // Okay, we have a legal flexible array member at the end of the struct. 2163 if (Record) 2164 Record->setHasFlexibleArrayMember(true); 2165 } 2166 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 2167 /// field of another structure or the element of an array. 2168 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 2169 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 2170 // If this is a member of a union, then entire union becomes "flexible". 2171 if (Record && Record->isUnion()) { 2172 Record->setHasFlexibleArrayMember(true); 2173 } else { 2174 // If this is a struct/class and this is not the last element, reject 2175 // it. Note that GCC supports variable sized arrays in the middle of 2176 // structures. 2177 if (i != NumFields-1) { 2178 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 2179 FD->getName()); 2180 FD->setInvalidDecl(); 2181 EnclosingDecl->setInvalidDecl(); 2182 continue; 2183 } 2184 // We support flexible arrays at the end of structs in other structs 2185 // as an extension. 2186 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 2187 FD->getName()); 2188 if (Record) 2189 Record->setHasFlexibleArrayMember(true); 2190 } 2191 } 2192 } 2193 /// A field cannot be an Objective-c object 2194 if (FDTy->isObjCInterfaceType()) { 2195 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2196 FD->getName()); 2197 FD->setInvalidDecl(); 2198 EnclosingDecl->setInvalidDecl(); 2199 continue; 2200 } 2201 // Keep track of the number of named members. 2202 if (IdentifierInfo *II = FD->getIdentifier()) { 2203 // Detect duplicate member names. 2204 if (!FieldIDs.insert(II)) { 2205 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2206 // Find the previous decl. 2207 SourceLocation PrevLoc; 2208 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 2209 assert(i != e && "Didn't find previous def!"); 2210 if (RecFields[i]->getIdentifier() == II) { 2211 PrevLoc = RecFields[i]->getLocation(); 2212 break; 2213 } 2214 } 2215 Diag(PrevLoc, diag::err_previous_definition); 2216 FD->setInvalidDecl(); 2217 EnclosingDecl->setInvalidDecl(); 2218 continue; 2219 } 2220 ++NumNamedMembers; 2221 } 2222 } 2223 2224 // Okay, we successfully defined 'Record'. 2225 if (Record) { 2226 Record->defineBody(Context, &RecFields[0], RecFields.size()); 2227 // If this is a C++ record, HandleTagDeclDefinition will be invoked in 2228 // Sema::ActOnFinishCXXClassDef. 2229 if (!isa<CXXRecordDecl>(Record)) 2230 Consumer.HandleTagDeclDefinition(Record); 2231 } else { 2232 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2233 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2234 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2235 else if (ObjCImplementationDecl *IMPDecl = 2236 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2237 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2238 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2239 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2240 } 2241 } 2242} 2243 2244Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2245 DeclTy *lastEnumConst, 2246 SourceLocation IdLoc, IdentifierInfo *Id, 2247 SourceLocation EqualLoc, ExprTy *val) { 2248 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2249 EnumConstantDecl *LastEnumConst = 2250 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2251 Expr *Val = static_cast<Expr*>(val); 2252 2253 // The scope passed in may not be a decl scope. Zip up the scope tree until 2254 // we find one that is. 2255 while ((S->getFlags() & Scope::DeclScope) == 0) 2256 S = S->getParent(); 2257 2258 // Verify that there isn't already something declared with this name in this 2259 // scope. 2260 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2261 // When in C++, we may get a TagDecl with the same name; in this case the 2262 // enum constant will 'hide' the tag. 2263 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 2264 "Received TagDecl when not in C++!"); 2265 if (!isa<TagDecl>(PrevDecl) && 2266 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 2267 if (isa<EnumConstantDecl>(PrevDecl)) 2268 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2269 else 2270 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2271 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2272 delete Val; 2273 return 0; 2274 } 2275 } 2276 2277 llvm::APSInt EnumVal(32); 2278 QualType EltTy; 2279 if (Val) { 2280 // Make sure to promote the operand type to int. 2281 UsualUnaryConversions(Val); 2282 2283 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2284 SourceLocation ExpLoc; 2285 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2286 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2287 Id->getName()); 2288 delete Val; 2289 Val = 0; // Just forget about it. 2290 } else { 2291 EltTy = Val->getType(); 2292 } 2293 } 2294 2295 if (!Val) { 2296 if (LastEnumConst) { 2297 // Assign the last value + 1. 2298 EnumVal = LastEnumConst->getInitVal(); 2299 ++EnumVal; 2300 2301 // Check for overflow on increment. 2302 if (EnumVal < LastEnumConst->getInitVal()) 2303 Diag(IdLoc, diag::warn_enum_value_overflow); 2304 2305 EltTy = LastEnumConst->getType(); 2306 } else { 2307 // First value, set to zero. 2308 EltTy = Context.IntTy; 2309 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2310 } 2311 } 2312 2313 EnumConstantDecl *New = 2314 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2315 Val, EnumVal, 2316 LastEnumConst); 2317 2318 // Register this decl in the current scope stack. 2319 PushOnScopeChains(New, S); 2320 return New; 2321} 2322 2323// FIXME: For consistency with ActOnFields(), we should have the parser 2324// pass in the source location for the left/right braces. 2325void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2326 DeclTy **Elements, unsigned NumElements) { 2327 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2328 2329 if (Enum && Enum->isDefinition()) { 2330 // Diagnose code like: 2331 // enum e0 { 2332 // E0 = sizeof(enum e0 { E1 }) 2333 // }; 2334 Diag(Enum->getLocation(), diag::err_nested_redefinition, 2335 Enum->getName()); 2336 Diag(EnumLoc, diag::err_previous_definition); 2337 Enum->setInvalidDecl(); 2338 return; 2339 } 2340 // TODO: If the result value doesn't fit in an int, it must be a long or long 2341 // long value. ISO C does not support this, but GCC does as an extension, 2342 // emit a warning. 2343 unsigned IntWidth = Context.Target.getIntWidth(); 2344 2345 // Verify that all the values are okay, compute the size of the values, and 2346 // reverse the list. 2347 unsigned NumNegativeBits = 0; 2348 unsigned NumPositiveBits = 0; 2349 2350 // Keep track of whether all elements have type int. 2351 bool AllElementsInt = true; 2352 2353 EnumConstantDecl *EltList = 0; 2354 for (unsigned i = 0; i != NumElements; ++i) { 2355 EnumConstantDecl *ECD = 2356 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2357 if (!ECD) continue; // Already issued a diagnostic. 2358 2359 // If the enum value doesn't fit in an int, emit an extension warning. 2360 const llvm::APSInt &InitVal = ECD->getInitVal(); 2361 assert(InitVal.getBitWidth() >= IntWidth && 2362 "Should have promoted value to int"); 2363 if (InitVal.getBitWidth() > IntWidth) { 2364 llvm::APSInt V(InitVal); 2365 V.trunc(IntWidth); 2366 V.extend(InitVal.getBitWidth()); 2367 if (V != InitVal) 2368 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2369 InitVal.toString(10)); 2370 } 2371 2372 // Keep track of the size of positive and negative values. 2373 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2374 NumPositiveBits = std::max(NumPositiveBits, 2375 (unsigned)InitVal.getActiveBits()); 2376 else 2377 NumNegativeBits = std::max(NumNegativeBits, 2378 (unsigned)InitVal.getMinSignedBits()); 2379 2380 // Keep track of whether every enum element has type int (very commmon). 2381 if (AllElementsInt) 2382 AllElementsInt = ECD->getType() == Context.IntTy; 2383 2384 ECD->setNextDeclarator(EltList); 2385 EltList = ECD; 2386 } 2387 2388 // Figure out the type that should be used for this enum. 2389 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2390 QualType BestType; 2391 unsigned BestWidth; 2392 2393 if (NumNegativeBits) { 2394 // If there is a negative value, figure out the smallest integer type (of 2395 // int/long/longlong) that fits. 2396 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2397 BestType = Context.IntTy; 2398 BestWidth = IntWidth; 2399 } else { 2400 BestWidth = Context.Target.getLongWidth(); 2401 2402 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2403 BestType = Context.LongTy; 2404 else { 2405 BestWidth = Context.Target.getLongLongWidth(); 2406 2407 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2408 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2409 BestType = Context.LongLongTy; 2410 } 2411 } 2412 } else { 2413 // If there is no negative value, figure out which of uint, ulong, ulonglong 2414 // fits. 2415 if (NumPositiveBits <= IntWidth) { 2416 BestType = Context.UnsignedIntTy; 2417 BestWidth = IntWidth; 2418 } else if (NumPositiveBits <= 2419 (BestWidth = Context.Target.getLongWidth())) { 2420 BestType = Context.UnsignedLongTy; 2421 } else { 2422 BestWidth = Context.Target.getLongLongWidth(); 2423 assert(NumPositiveBits <= BestWidth && 2424 "How could an initializer get larger than ULL?"); 2425 BestType = Context.UnsignedLongLongTy; 2426 } 2427 } 2428 2429 // Loop over all of the enumerator constants, changing their types to match 2430 // the type of the enum if needed. 2431 for (unsigned i = 0; i != NumElements; ++i) { 2432 EnumConstantDecl *ECD = 2433 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2434 if (!ECD) continue; // Already issued a diagnostic. 2435 2436 // Standard C says the enumerators have int type, but we allow, as an 2437 // extension, the enumerators to be larger than int size. If each 2438 // enumerator value fits in an int, type it as an int, otherwise type it the 2439 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2440 // that X has type 'int', not 'unsigned'. 2441 if (ECD->getType() == Context.IntTy) { 2442 // Make sure the init value is signed. 2443 llvm::APSInt IV = ECD->getInitVal(); 2444 IV.setIsSigned(true); 2445 ECD->setInitVal(IV); 2446 continue; // Already int type. 2447 } 2448 2449 // Determine whether the value fits into an int. 2450 llvm::APSInt InitVal = ECD->getInitVal(); 2451 bool FitsInInt; 2452 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2453 FitsInInt = InitVal.getActiveBits() < IntWidth; 2454 else 2455 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2456 2457 // If it fits into an integer type, force it. Otherwise force it to match 2458 // the enum decl type. 2459 QualType NewTy; 2460 unsigned NewWidth; 2461 bool NewSign; 2462 if (FitsInInt) { 2463 NewTy = Context.IntTy; 2464 NewWidth = IntWidth; 2465 NewSign = true; 2466 } else if (ECD->getType() == BestType) { 2467 // Already the right type! 2468 continue; 2469 } else { 2470 NewTy = BestType; 2471 NewWidth = BestWidth; 2472 NewSign = BestType->isSignedIntegerType(); 2473 } 2474 2475 // Adjust the APSInt value. 2476 InitVal.extOrTrunc(NewWidth); 2477 InitVal.setIsSigned(NewSign); 2478 ECD->setInitVal(InitVal); 2479 2480 // Adjust the Expr initializer and type. 2481 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2482 ECD->setType(NewTy); 2483 } 2484 2485 Enum->defineElements(EltList, BestType); 2486 Consumer.HandleTagDeclDefinition(Enum); 2487} 2488 2489Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2490 ExprTy *expr) { 2491 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2492 2493 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2494} 2495 2496Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2497 SourceLocation LBrace, 2498 SourceLocation RBrace, 2499 const char *Lang, 2500 unsigned StrSize, 2501 DeclTy *D) { 2502 LinkageSpecDecl::LanguageIDs Language; 2503 Decl *dcl = static_cast<Decl *>(D); 2504 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2505 Language = LinkageSpecDecl::lang_c; 2506 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2507 Language = LinkageSpecDecl::lang_cxx; 2508 else { 2509 Diag(Loc, diag::err_bad_language); 2510 return 0; 2511 } 2512 2513 // FIXME: Add all the various semantics of linkage specifications 2514 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2515} 2516