SemaDecl.cpp revision e267ff35b2f4e9d2b0d8bf24109d41cc7398b61b
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29 30using namespace clang; 31 32Sema::TypeTy *Sema::isTypeName(IdentifierInfo &II, Scope *S, 33 const CXXScopeSpec *SS) { 34 DeclContext *DC = 0; 35 if (SS) { 36 if (SS->isInvalid()) 37 return 0; 38 DC = static_cast<DeclContext*>(SS->getScopeRep()); 39 } 40 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC, false); 41 42 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 43 isa<ObjCInterfaceDecl>(IIDecl) || 44 isa<TagDecl>(IIDecl) || 45 isa<TemplateTypeParmDecl>(IIDecl))) 46 return IIDecl; 47 return 0; 48} 49 50DeclContext *Sema::getContainingDC(DeclContext *DC) { 51 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 52 // A C++ out-of-line method will return to the file declaration context. 53 if (MD->isOutOfLineDefinition()) 54 return MD->getLexicalDeclContext(); 55 56 // A C++ inline method is parsed *after* the topmost class it was declared in 57 // is fully parsed (it's "complete"). 58 // The parsing of a C++ inline method happens at the declaration context of 59 // the topmost (non-nested) class it is lexically declared in. 60 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 61 DC = MD->getParent(); 62 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 63 DC = RD; 64 65 // Return the declaration context of the topmost class the inline method is 66 // declared in. 67 return DC; 68 } 69 70 if (isa<ObjCMethodDecl>(DC)) 71 return Context.getTranslationUnitDecl(); 72 73 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(DC)) 74 return SD->getLexicalDeclContext(); 75 76 return DC->getLexicalParent(); 77} 78 79void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 80 assert(getContainingDC(DC) == CurContext && 81 "The next DeclContext should be lexically contained in the current one."); 82 CurContext = DC; 83 S->setEntity(DC); 84} 85 86void Sema::PopDeclContext() { 87 assert(CurContext && "DeclContext imbalance!"); 88 89 CurContext = getContainingDC(CurContext); 90} 91 92/// Add this decl to the scope shadowed decl chains. 93void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 94 S->AddDecl(D); 95 96 // C++ [basic.scope]p4: 97 // -- exactly one declaration shall declare a class name or 98 // enumeration name that is not a typedef name and the other 99 // declarations shall all refer to the same object or 100 // enumerator, or all refer to functions and function templates; 101 // in this case the class name or enumeration name is hidden. 102 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 103 // We are pushing the name of a tag (enum or class). 104 if (CurContext == TD->getDeclContext()) { 105 // We're pushing the tag into the current context, which might 106 // require some reshuffling in the identifier resolver. 107 IdentifierResolver::iterator 108 I = IdResolver.begin(TD->getIdentifier(), CurContext, 109 false/*LookInParentCtx*/); 110 if (I != IdResolver.end()) { 111 // There is already a declaration with the same name in the same 112 // scope. It must be found before we find the new declaration, 113 // so swap the order on the shadowed declaration chain. 114 IdResolver.AddShadowedDecl(TD, *I); 115 116 // Add this declaration to the current context. 117 CurContext->addDecl(Context, TD); 118 119 return; 120 } 121 } 122 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 123 // We are pushing the name of a function, which might be an 124 // overloaded name. 125 FunctionDecl *FD = cast<FunctionDecl>(D); 126 Decl *Prev = LookupDecl(FD->getDeclName(), Decl::IDNS_Ordinary, S, 127 FD->getDeclContext(), false, false); 128 if (Prev && (isa<OverloadedFunctionDecl>(Prev) || isa<FunctionDecl>(Prev))) { 129 // There is already a declaration with the same name in 130 // the same scope. It must be a function or an overloaded 131 // function. 132 OverloadedFunctionDecl* Ovl = dyn_cast<OverloadedFunctionDecl>(Prev); 133 if (!Ovl) { 134 // We haven't yet overloaded this function. Take the existing 135 // FunctionDecl and put it into an OverloadedFunctionDecl. 136 Ovl = OverloadedFunctionDecl::Create(Context, 137 FD->getDeclContext(), 138 FD->getDeclName()); 139 Ovl->addOverload(cast<FunctionDecl>(Prev)); 140 141 // If there is an ame binding for the existing FunctionDecl, 142 // remove it. 143 for (IdentifierResolver::iterator I 144 = IdResolver.begin(FD->getDeclName(), FD->getDeclContext(), 145 false/*LookInParentCtx*/), 146 E = IdResolver.end(); I != E; ++I) { 147 if (*I == Prev) { 148 IdResolver.RemoveDecl(*I); 149 S->RemoveDecl(*I); 150 break; 151 } 152 } 153 154 // Add the name binding for the OverloadedFunctionDecl. 155 IdResolver.AddDecl(Ovl); 156 157 // Update the context with the newly-created overloaded 158 // function set. 159 FD->getDeclContext()->insert(Context, Ovl); 160 161 S->AddDecl(Ovl); 162 } 163 164 // We added this function declaration to the scope earlier, but 165 // we don't want it there because it is part of the overloaded 166 // function declaration. 167 S->RemoveDecl(FD); 168 169 // We have an OverloadedFunctionDecl. Add the new FunctionDecl 170 // to its list of overloads. 171 Ovl->addOverload(FD); 172 173 // Add this new function declaration to the declaration context. 174 CurContext->addDecl(Context, FD, false); 175 176 return; 177 } 178 } 179 180 // Add scoped declarations into their context, so that they can be 181 // found later. Declarations without a context won't be inserted 182 // into any context. 183 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D)) 184 CurContext->addDecl(Context, SD); 185 186 IdResolver.AddDecl(D); 187} 188 189void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 190 if (S->decl_empty()) return; 191 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 192 "Scope shouldn't contain decls!"); 193 194 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 195 I != E; ++I) { 196 Decl *TmpD = static_cast<Decl*>(*I); 197 assert(TmpD && "This decl didn't get pushed??"); 198 199 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 200 NamedDecl *D = cast<NamedDecl>(TmpD); 201 202 if (!D->getDeclName()) continue; 203 204 // Remove this name from our lexical scope. 205 IdResolver.RemoveDecl(D); 206 } 207} 208 209/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 210/// return 0 if one not found. 211ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 212 // The third "scope" argument is 0 since we aren't enabling lazy built-in 213 // creation from this context. 214 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 215 216 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 217} 218 219/// LookupDecl - Look up the inner-most declaration in the specified 220/// namespace. 221Decl *Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 222 const DeclContext *LookupCtx, 223 bool enableLazyBuiltinCreation, 224 bool LookInParent) { 225 if (!Name) return 0; 226 unsigned NS = NSI; 227 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 228 NS |= Decl::IDNS_Tag; 229 230 if (LookupCtx == 0 && 231 (!getLangOptions().CPlusPlus || (NS == Decl::IDNS_Label))) { 232 // Unqualified name lookup in C/Objective-C and name lookup for 233 // labels in C++ is purely lexical, so search in the 234 // declarations attached to the name. 235 assert(!LookupCtx && "Can't perform qualified name lookup here"); 236 IdentifierResolver::iterator I 237 = IdResolver.begin(Name, CurContext, LookInParent); 238 239 // Scan up the scope chain looking for a decl that matches this 240 // identifier that is in the appropriate namespace. This search 241 // should not take long, as shadowing of names is uncommon, and 242 // deep shadowing is extremely uncommon. 243 for (; I != IdResolver.end(); ++I) 244 if ((*I)->getIdentifierNamespace() & NS) 245 return *I; 246 } else if (LookupCtx) { 247 assert(getLangOptions().CPlusPlus && "No qualified name lookup in C"); 248 249 // Perform qualified name lookup into the LookupCtx. 250 // FIXME: Will need to look into base classes and such. 251 DeclContext::lookup_const_iterator I, E; 252 for (llvm::tie(I, E) = LookupCtx->lookup(Context, Name); I != E; ++I) 253 if ((*I)->getIdentifierNamespace() & NS) 254 return *I; 255 } else { 256 // Name lookup for ordinary names and tag names in C++ requires 257 // looking into scopes that aren't strictly lexical, and 258 // therefore we walk through the context as well as walking 259 // through the scopes. 260 IdentifierResolver::iterator 261 I = IdResolver.begin(Name, CurContext, true/*LookInParentCtx*/), 262 IEnd = IdResolver.end(); 263 for (; S; S = S->getParent()) { 264 // Check whether the IdResolver has anything in this scope. 265 // FIXME: The isDeclScope check could be expensive. Can we do better? 266 for (; I != IEnd && S->isDeclScope(*I); ++I) 267 if ((*I)->getIdentifierNamespace() & NS) 268 return *I; 269 270 // If there is an entity associated with this scope, it's a 271 // DeclContext. We might need to perform qualified lookup into 272 // it. 273 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 274 while (Ctx && Ctx->isFunctionOrMethod()) 275 Ctx = Ctx->getParent(); 276 while (Ctx && (Ctx->isNamespace() || Ctx->isCXXRecord())) { 277 // Look for declarations of this name in this scope. 278 DeclContext::lookup_const_iterator I, E; 279 for (llvm::tie(I, E) = Ctx->lookup(Context, Name); I != E; ++I) { 280 // FIXME: Cache this result in the IdResolver 281 if ((*I)->getIdentifierNamespace() & NS) 282 return *I; 283 } 284 285 Ctx = Ctx->getParent(); 286 } 287 288 if (!LookInParent) 289 return 0; 290 } 291 } 292 293 // If we didn't find a use of this identifier, and if the identifier 294 // corresponds to a compiler builtin, create the decl object for the builtin 295 // now, injecting it into translation unit scope, and return it. 296 if (NS & Decl::IDNS_Ordinary) { 297 IdentifierInfo *II = Name.getAsIdentifierInfo(); 298 if (enableLazyBuiltinCreation && II && 299 (LookupCtx == 0 || isa<TranslationUnitDecl>(LookupCtx))) { 300 // If this is a builtin on this (or all) targets, create the decl. 301 if (unsigned BuiltinID = II->getBuiltinID()) 302 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 303 } 304 if (getLangOptions().ObjC1 && II) { 305 // @interface and @compatibility_alias introduce typedef-like names. 306 // Unlike typedef's, they can only be introduced at file-scope (and are 307 // therefore not scoped decls). They can, however, be shadowed by 308 // other names in IDNS_Ordinary. 309 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 310 if (IDI != ObjCInterfaceDecls.end()) 311 return IDI->second; 312 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 313 if (I != ObjCAliasDecls.end()) 314 return I->second->getClassInterface(); 315 } 316 } 317 return 0; 318} 319 320void Sema::InitBuiltinVaListType() { 321 if (!Context.getBuiltinVaListType().isNull()) 322 return; 323 324 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 325 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 326 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 327 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 328} 329 330/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 331/// lazily create a decl for it. 332ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 333 Scope *S) { 334 Builtin::ID BID = (Builtin::ID)bid; 335 336 if (Context.BuiltinInfo.hasVAListUse(BID)) 337 InitBuiltinVaListType(); 338 339 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 340 FunctionDecl *New = FunctionDecl::Create(Context, 341 Context.getTranslationUnitDecl(), 342 SourceLocation(), II, R, 343 FunctionDecl::Extern, false, 0); 344 345 // Create Decl objects for each parameter, adding them to the 346 // FunctionDecl. 347 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 348 llvm::SmallVector<ParmVarDecl*, 16> Params; 349 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 350 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 351 FT->getArgType(i), VarDecl::None, 0, 352 0)); 353 New->setParams(&Params[0], Params.size()); 354 } 355 356 357 358 // TUScope is the translation-unit scope to insert this function into. 359 PushOnScopeChains(New, TUScope); 360 return New; 361} 362 363/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 364/// everything from the standard library is defined. 365NamespaceDecl *Sema::GetStdNamespace() { 366 if (!StdNamespace) { 367 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 368 DeclContext *Global = Context.getTranslationUnitDecl(); 369 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Tag | Decl::IDNS_Ordinary, 370 0, Global, /*enableLazyBuiltinCreation=*/false); 371 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 372 } 373 return StdNamespace; 374} 375 376/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 377/// and scope as a previous declaration 'Old'. Figure out how to resolve this 378/// situation, merging decls or emitting diagnostics as appropriate. 379/// 380TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 381 // Allow multiple definitions for ObjC built-in typedefs. 382 // FIXME: Verify the underlying types are equivalent! 383 if (getLangOptions().ObjC1) { 384 const IdentifierInfo *TypeID = New->getIdentifier(); 385 switch (TypeID->getLength()) { 386 default: break; 387 case 2: 388 if (!TypeID->isStr("id")) 389 break; 390 Context.setObjCIdType(New); 391 return New; 392 case 5: 393 if (!TypeID->isStr("Class")) 394 break; 395 Context.setObjCClassType(New); 396 return New; 397 case 3: 398 if (!TypeID->isStr("SEL")) 399 break; 400 Context.setObjCSelType(New); 401 return New; 402 case 8: 403 if (!TypeID->isStr("Protocol")) 404 break; 405 Context.setObjCProtoType(New->getUnderlyingType()); 406 return New; 407 } 408 // Fall through - the typedef name was not a builtin type. 409 } 410 // Verify the old decl was also a typedef. 411 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 412 if (!Old) { 413 Diag(New->getLocation(), diag::err_redefinition_different_kind) 414 << New->getDeclName(); 415 Diag(OldD->getLocation(), diag::note_previous_definition); 416 return New; 417 } 418 419 // If the typedef types are not identical, reject them in all languages and 420 // with any extensions enabled. 421 if (Old->getUnderlyingType() != New->getUnderlyingType() && 422 Context.getCanonicalType(Old->getUnderlyingType()) != 423 Context.getCanonicalType(New->getUnderlyingType())) { 424 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 425 << New->getUnderlyingType() << Old->getUnderlyingType(); 426 Diag(Old->getLocation(), diag::note_previous_definition); 427 return Old; 428 } 429 430 if (getLangOptions().Microsoft) return New; 431 432 // C++ [dcl.typedef]p2: 433 // In a given non-class scope, a typedef specifier can be used to 434 // redefine the name of any type declared in that scope to refer 435 // to the type to which it already refers. 436 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 437 return New; 438 439 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 440 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 441 // *either* declaration is in a system header. The code below implements 442 // this adhoc compatibility rule. FIXME: The following code will not 443 // work properly when compiling ".i" files (containing preprocessed output). 444 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 445 SourceManager &SrcMgr = Context.getSourceManager(); 446 if (SrcMgr.isInSystemHeader(Old->getLocation())) 447 return New; 448 if (SrcMgr.isInSystemHeader(New->getLocation())) 449 return New; 450 } 451 452 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 453 Diag(Old->getLocation(), diag::note_previous_definition); 454 return New; 455} 456 457/// DeclhasAttr - returns true if decl Declaration already has the target 458/// attribute. 459static bool DeclHasAttr(const Decl *decl, const Attr *target) { 460 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 461 if (attr->getKind() == target->getKind()) 462 return true; 463 464 return false; 465} 466 467/// MergeAttributes - append attributes from the Old decl to the New one. 468static void MergeAttributes(Decl *New, Decl *Old) { 469 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 470 471 while (attr) { 472 tmp = attr; 473 attr = attr->getNext(); 474 475 if (!DeclHasAttr(New, tmp)) { 476 New->addAttr(tmp); 477 } else { 478 tmp->setNext(0); 479 delete(tmp); 480 } 481 } 482 483 Old->invalidateAttrs(); 484} 485 486/// MergeFunctionDecl - We just parsed a function 'New' from 487/// declarator D which has the same name and scope as a previous 488/// declaration 'Old'. Figure out how to resolve this situation, 489/// merging decls or emitting diagnostics as appropriate. 490/// Redeclaration will be set true if this New is a redeclaration OldD. 491/// 492/// In C++, New and Old must be declarations that are not 493/// overloaded. Use IsOverload to determine whether New and Old are 494/// overloaded, and to select the Old declaration that New should be 495/// merged with. 496FunctionDecl * 497Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 498 assert(!isa<OverloadedFunctionDecl>(OldD) && 499 "Cannot merge with an overloaded function declaration"); 500 501 Redeclaration = false; 502 // Verify the old decl was also a function. 503 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 504 if (!Old) { 505 Diag(New->getLocation(), diag::err_redefinition_different_kind) 506 << New->getDeclName(); 507 Diag(OldD->getLocation(), diag::note_previous_definition); 508 return New; 509 } 510 511 // Determine whether the previous declaration was a definition, 512 // implicit declaration, or a declaration. 513 diag::kind PrevDiag; 514 if (Old->isThisDeclarationADefinition()) 515 PrevDiag = diag::note_previous_definition; 516 else if (Old->isImplicit()) 517 PrevDiag = diag::note_previous_implicit_declaration; 518 else 519 PrevDiag = diag::note_previous_declaration; 520 521 QualType OldQType = Context.getCanonicalType(Old->getType()); 522 QualType NewQType = Context.getCanonicalType(New->getType()); 523 524 if (getLangOptions().CPlusPlus) { 525 // (C++98 13.1p2): 526 // Certain function declarations cannot be overloaded: 527 // -- Function declarations that differ only in the return type 528 // cannot be overloaded. 529 QualType OldReturnType 530 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 531 QualType NewReturnType 532 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 533 if (OldReturnType != NewReturnType) { 534 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 535 Diag(Old->getLocation(), PrevDiag); 536 return New; 537 } 538 539 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 540 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 541 if (OldMethod && NewMethod) { 542 // -- Member function declarations with the same name and the 543 // same parameter types cannot be overloaded if any of them 544 // is a static member function declaration. 545 if (OldMethod->isStatic() || NewMethod->isStatic()) { 546 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 547 Diag(Old->getLocation(), PrevDiag); 548 return New; 549 } 550 } 551 552 // (C++98 8.3.5p3): 553 // All declarations for a function shall agree exactly in both the 554 // return type and the parameter-type-list. 555 if (OldQType == NewQType) { 556 // We have a redeclaration. 557 MergeAttributes(New, Old); 558 Redeclaration = true; 559 return MergeCXXFunctionDecl(New, Old); 560 } 561 562 // Fall through for conflicting redeclarations and redefinitions. 563 } 564 565 // C: Function types need to be compatible, not identical. This handles 566 // duplicate function decls like "void f(int); void f(enum X);" properly. 567 if (!getLangOptions().CPlusPlus && 568 Context.typesAreCompatible(OldQType, NewQType)) { 569 MergeAttributes(New, Old); 570 Redeclaration = true; 571 return New; 572 } 573 574 // A function that has already been declared has been redeclared or defined 575 // with a different type- show appropriate diagnostic 576 577 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 578 // TODO: This is totally simplistic. It should handle merging functions 579 // together etc, merging extern int X; int X; ... 580 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 581 Diag(Old->getLocation(), PrevDiag); 582 return New; 583} 584 585/// Predicate for C "tentative" external object definitions (C99 6.9.2). 586static bool isTentativeDefinition(VarDecl *VD) { 587 if (VD->isFileVarDecl()) 588 return (!VD->getInit() && 589 (VD->getStorageClass() == VarDecl::None || 590 VD->getStorageClass() == VarDecl::Static)); 591 return false; 592} 593 594/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 595/// when dealing with C "tentative" external object definitions (C99 6.9.2). 596void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 597 bool VDIsTentative = isTentativeDefinition(VD); 598 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 599 600 for (IdentifierResolver::iterator 601 I = IdResolver.begin(VD->getIdentifier(), 602 VD->getDeclContext(), false/*LookInParentCtx*/), 603 E = IdResolver.end(); I != E; ++I) { 604 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 605 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 606 607 // Handle the following case: 608 // int a[10]; 609 // int a[]; - the code below makes sure we set the correct type. 610 // int a[11]; - this is an error, size isn't 10. 611 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 612 OldDecl->getType()->isConstantArrayType()) 613 VD->setType(OldDecl->getType()); 614 615 // Check for "tentative" definitions. We can't accomplish this in 616 // MergeVarDecl since the initializer hasn't been attached. 617 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 618 continue; 619 620 // Handle __private_extern__ just like extern. 621 if (OldDecl->getStorageClass() != VarDecl::Extern && 622 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 623 VD->getStorageClass() != VarDecl::Extern && 624 VD->getStorageClass() != VarDecl::PrivateExtern) { 625 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 626 Diag(OldDecl->getLocation(), diag::note_previous_definition); 627 } 628 } 629 } 630} 631 632/// MergeVarDecl - We just parsed a variable 'New' which has the same name 633/// and scope as a previous declaration 'Old'. Figure out how to resolve this 634/// situation, merging decls or emitting diagnostics as appropriate. 635/// 636/// Tentative definition rules (C99 6.9.2p2) are checked by 637/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 638/// definitions here, since the initializer hasn't been attached. 639/// 640VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 641 // Verify the old decl was also a variable. 642 VarDecl *Old = dyn_cast<VarDecl>(OldD); 643 if (!Old) { 644 Diag(New->getLocation(), diag::err_redefinition_different_kind) 645 << New->getDeclName(); 646 Diag(OldD->getLocation(), diag::note_previous_definition); 647 return New; 648 } 649 650 MergeAttributes(New, Old); 651 652 // Verify the types match. 653 QualType OldCType = Context.getCanonicalType(Old->getType()); 654 QualType NewCType = Context.getCanonicalType(New->getType()); 655 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 656 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 657 Diag(Old->getLocation(), diag::note_previous_definition); 658 return New; 659 } 660 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 661 if (New->getStorageClass() == VarDecl::Static && 662 (Old->getStorageClass() == VarDecl::None || 663 Old->getStorageClass() == VarDecl::Extern)) { 664 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 665 Diag(Old->getLocation(), diag::note_previous_definition); 666 return New; 667 } 668 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 669 if (New->getStorageClass() != VarDecl::Static && 670 Old->getStorageClass() == VarDecl::Static) { 671 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 672 Diag(Old->getLocation(), diag::note_previous_definition); 673 return New; 674 } 675 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 676 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 677 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 678 Diag(Old->getLocation(), diag::note_previous_definition); 679 } 680 return New; 681} 682 683/// CheckParmsForFunctionDef - Check that the parameters of the given 684/// function are appropriate for the definition of a function. This 685/// takes care of any checks that cannot be performed on the 686/// declaration itself, e.g., that the types of each of the function 687/// parameters are complete. 688bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 689 bool HasInvalidParm = false; 690 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 691 ParmVarDecl *Param = FD->getParamDecl(p); 692 693 // C99 6.7.5.3p4: the parameters in a parameter type list in a 694 // function declarator that is part of a function definition of 695 // that function shall not have incomplete type. 696 if (Param->getType()->isIncompleteType() && 697 !Param->isInvalidDecl()) { 698 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 699 << Param->getType(); 700 Param->setInvalidDecl(); 701 HasInvalidParm = true; 702 } 703 } 704 705 return HasInvalidParm; 706} 707 708/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 709/// no declarator (e.g. "struct foo;") is parsed. 710Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 711 // TODO: emit error on 'int;' or 'const enum foo;'. 712 // TODO: emit error on 'typedef int;' 713 // if (!DS.isMissingDeclaratorOk()) Diag(...); 714 715 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 716} 717 718bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 719 // Get the type before calling CheckSingleAssignmentConstraints(), since 720 // it can promote the expression. 721 QualType InitType = Init->getType(); 722 723 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 724 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 725 InitType, Init, "initializing"); 726} 727 728bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 729 const ArrayType *AT = Context.getAsArrayType(DeclT); 730 731 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 732 // C99 6.7.8p14. We have an array of character type with unknown size 733 // being initialized to a string literal. 734 llvm::APSInt ConstVal(32); 735 ConstVal = strLiteral->getByteLength() + 1; 736 // Return a new array type (C99 6.7.8p22). 737 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 738 ArrayType::Normal, 0); 739 } else { 740 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 741 // C99 6.7.8p14. We have an array of character type with known size. 742 // FIXME: Avoid truncation for 64-bit length strings. 743 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 744 Diag(strLiteral->getSourceRange().getBegin(), 745 diag::warn_initializer_string_for_char_array_too_long) 746 << strLiteral->getSourceRange(); 747 } 748 // Set type from "char *" to "constant array of char". 749 strLiteral->setType(DeclT); 750 // For now, we always return false (meaning success). 751 return false; 752} 753 754StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 755 const ArrayType *AT = Context.getAsArrayType(DeclType); 756 if (AT && AT->getElementType()->isCharType()) { 757 return dyn_cast<StringLiteral>(Init); 758 } 759 return 0; 760} 761 762bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 763 SourceLocation InitLoc, 764 DeclarationName InitEntity) { 765 // C++ [dcl.init.ref]p1: 766 // A variable declared to be a T&, that is "reference to type T" 767 // (8.3.2), shall be initialized by an object, or function, of 768 // type T or by an object that can be converted into a T. 769 if (DeclType->isReferenceType()) 770 return CheckReferenceInit(Init, DeclType); 771 772 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 773 // of unknown size ("[]") or an object type that is not a variable array type. 774 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 775 return Diag(InitLoc, diag::err_variable_object_no_init) 776 << VAT->getSizeExpr()->getSourceRange(); 777 778 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 779 if (!InitList) { 780 // FIXME: Handle wide strings 781 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 782 return CheckStringLiteralInit(strLiteral, DeclType); 783 784 // C++ [dcl.init]p14: 785 // -- If the destination type is a (possibly cv-qualified) class 786 // type: 787 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 788 QualType DeclTypeC = Context.getCanonicalType(DeclType); 789 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 790 791 // -- If the initialization is direct-initialization, or if it is 792 // copy-initialization where the cv-unqualified version of the 793 // source type is the same class as, or a derived class of, the 794 // class of the destination, constructors are considered. 795 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 796 IsDerivedFrom(InitTypeC, DeclTypeC)) { 797 CXXConstructorDecl *Constructor 798 = PerformInitializationByConstructor(DeclType, &Init, 1, 799 InitLoc, Init->getSourceRange(), 800 InitEntity, IK_Copy); 801 return Constructor == 0; 802 } 803 804 // -- Otherwise (i.e., for the remaining copy-initialization 805 // cases), user-defined conversion sequences that can 806 // convert from the source type to the destination type or 807 // (when a conversion function is used) to a derived class 808 // thereof are enumerated as described in 13.3.1.4, and the 809 // best one is chosen through overload resolution 810 // (13.3). If the conversion cannot be done or is 811 // ambiguous, the initialization is ill-formed. The 812 // function selected is called with the initializer 813 // expression as its argument; if the function is a 814 // constructor, the call initializes a temporary of the 815 // destination type. 816 // FIXME: We're pretending to do copy elision here; return to 817 // this when we have ASTs for such things. 818 if (!PerformImplicitConversion(Init, DeclType)) 819 return false; 820 821 return Diag(InitLoc, diag::err_typecheck_convert_incompatible) 822 << DeclType << InitEntity << "initializing" 823 << Init->getSourceRange(); 824 } 825 826 // C99 6.7.8p16. 827 if (DeclType->isArrayType()) 828 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 829 << Init->getSourceRange(); 830 831 return CheckSingleInitializer(Init, DeclType); 832 } else if (getLangOptions().CPlusPlus) { 833 // C++ [dcl.init]p14: 834 // [...] If the class is an aggregate (8.5.1), and the initializer 835 // is a brace-enclosed list, see 8.5.1. 836 // 837 // Note: 8.5.1 is handled below; here, we diagnose the case where 838 // we have an initializer list and a destination type that is not 839 // an aggregate. 840 // FIXME: In C++0x, this is yet another form of initialization. 841 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 842 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 843 if (!ClassDecl->isAggregate()) 844 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 845 << DeclType << Init->getSourceRange(); 846 } 847 } 848 849 InitListChecker CheckInitList(this, InitList, DeclType); 850 return CheckInitList.HadError(); 851} 852 853/// GetNameForDeclarator - Determine the full declaration name for the 854/// given Declarator. 855DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 856 switch (D.getKind()) { 857 case Declarator::DK_Abstract: 858 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 859 return DeclarationName(); 860 861 case Declarator::DK_Normal: 862 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 863 return DeclarationName(D.getIdentifier()); 864 865 case Declarator::DK_Constructor: { 866 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 867 Ty = Context.getCanonicalType(Ty); 868 return Context.DeclarationNames.getCXXConstructorName(Ty); 869 } 870 871 case Declarator::DK_Destructor: { 872 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 873 Ty = Context.getCanonicalType(Ty); 874 return Context.DeclarationNames.getCXXDestructorName(Ty); 875 } 876 877 case Declarator::DK_Conversion: { 878 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 879 Ty = Context.getCanonicalType(Ty); 880 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 881 } 882 883 case Declarator::DK_Operator: 884 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 885 return Context.DeclarationNames.getCXXOperatorName( 886 D.getOverloadedOperator()); 887 } 888 889 assert(false && "Unknown name kind"); 890 return DeclarationName(); 891} 892 893Sema::DeclTy * 894Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 895 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 896 DeclarationName Name = GetNameForDeclarator(D); 897 898 // All of these full declarators require an identifier. If it doesn't have 899 // one, the ParsedFreeStandingDeclSpec action should be used. 900 if (!Name) { 901 if (!D.getInvalidType()) // Reject this if we think it is valid. 902 Diag(D.getDeclSpec().getSourceRange().getBegin(), 903 diag::err_declarator_need_ident) 904 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 905 return 0; 906 } 907 908 // The scope passed in may not be a decl scope. Zip up the scope tree until 909 // we find one that is. 910 while ((S->getFlags() & Scope::DeclScope) == 0 || 911 (S->getFlags() & Scope::TemplateParamScope) != 0) 912 S = S->getParent(); 913 914 DeclContext *DC; 915 Decl *PrevDecl; 916 ScopedDecl *New; 917 bool InvalidDecl = false; 918 919 // See if this is a redefinition of a variable in the same scope. 920 if (!D.getCXXScopeSpec().isSet()) { 921 DC = CurContext; 922 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 923 } else { // Something like "int foo::x;" 924 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 925 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 926 927 // C++ 7.3.1.2p2: 928 // Members (including explicit specializations of templates) of a named 929 // namespace can also be defined outside that namespace by explicit 930 // qualification of the name being defined, provided that the entity being 931 // defined was already declared in the namespace and the definition appears 932 // after the point of declaration in a namespace that encloses the 933 // declarations namespace. 934 // 935 if (PrevDecl == 0) { 936 // No previous declaration in the qualifying scope. 937 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 938 << Name << D.getCXXScopeSpec().getRange(); 939 InvalidDecl = true; 940 } else if (!CurContext->Encloses(DC)) { 941 // The qualifying scope doesn't enclose the original declaration. 942 // Emit diagnostic based on current scope. 943 SourceLocation L = D.getIdentifierLoc(); 944 SourceRange R = D.getCXXScopeSpec().getRange(); 945 if (isa<FunctionDecl>(CurContext)) { 946 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 947 } else { 948 Diag(L, diag::err_invalid_declarator_scope) 949 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 950 } 951 InvalidDecl = true; 952 } 953 } 954 955 if (PrevDecl && PrevDecl->isTemplateParameter()) { 956 // Maybe we will complain about the shadowed template parameter. 957 InvalidDecl = InvalidDecl 958 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 959 // Just pretend that we didn't see the previous declaration. 960 PrevDecl = 0; 961 } 962 963 // In C++, the previous declaration we find might be a tag type 964 // (class or enum). In this case, the new declaration will hide the 965 // tag type. 966 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 967 PrevDecl = 0; 968 969 QualType R = GetTypeForDeclarator(D, S); 970 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 971 972 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 973 // Check that there are no default arguments (C++ only). 974 if (getLangOptions().CPlusPlus) 975 CheckExtraCXXDefaultArguments(D); 976 977 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 978 if (!NewTD) return 0; 979 980 // Handle attributes prior to checking for duplicates in MergeVarDecl 981 ProcessDeclAttributes(NewTD, D); 982 // Merge the decl with the existing one if appropriate. If the decl is 983 // in an outer scope, it isn't the same thing. 984 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 985 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 986 if (NewTD == 0) return 0; 987 } 988 New = NewTD; 989 if (S->getFnParent() == 0) { 990 // C99 6.7.7p2: If a typedef name specifies a variably modified type 991 // then it shall have block scope. 992 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 993 if (NewTD->getUnderlyingType()->isVariableArrayType()) 994 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 995 else 996 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 997 998 InvalidDecl = true; 999 } 1000 } 1001 } else if (R.getTypePtr()->isFunctionType()) { 1002 FunctionDecl::StorageClass SC = FunctionDecl::None; 1003 switch (D.getDeclSpec().getStorageClassSpec()) { 1004 default: assert(0 && "Unknown storage class!"); 1005 case DeclSpec::SCS_auto: 1006 case DeclSpec::SCS_register: 1007 case DeclSpec::SCS_mutable: 1008 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1009 InvalidDecl = true; 1010 break; 1011 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1012 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1013 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1014 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1015 } 1016 1017 bool isInline = D.getDeclSpec().isInlineSpecified(); 1018 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1019 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1020 1021 FunctionDecl *NewFD; 1022 if (D.getKind() == Declarator::DK_Constructor) { 1023 // This is a C++ constructor declaration. 1024 assert(DC->isCXXRecord() && 1025 "Constructors can only be declared in a member context"); 1026 1027 bool isInvalidDecl = CheckConstructorDeclarator(D, R, SC); 1028 1029 // Create the new declaration 1030 NewFD = CXXConstructorDecl::Create(Context, 1031 cast<CXXRecordDecl>(DC), 1032 D.getIdentifierLoc(), Name, R, 1033 isExplicit, isInline, 1034 /*isImplicitlyDeclared=*/false); 1035 1036 if (isInvalidDecl) 1037 NewFD->setInvalidDecl(); 1038 } else if (D.getKind() == Declarator::DK_Destructor) { 1039 // This is a C++ destructor declaration. 1040 if (DC->isCXXRecord()) { 1041 bool isInvalidDecl = CheckDestructorDeclarator(D, R, SC); 1042 1043 NewFD = CXXDestructorDecl::Create(Context, 1044 cast<CXXRecordDecl>(DC), 1045 D.getIdentifierLoc(), Name, R, 1046 isInline, 1047 /*isImplicitlyDeclared=*/false); 1048 1049 if (isInvalidDecl) 1050 NewFD->setInvalidDecl(); 1051 } else { 1052 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1053 // Create a FunctionDecl to satisfy the function definition parsing 1054 // code path. 1055 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1056 Name, R, SC, isInline, LastDeclarator, 1057 // FIXME: Move to DeclGroup... 1058 D.getDeclSpec().getSourceRange().getBegin()); 1059 NewFD->setInvalidDecl(); 1060 } 1061 } else if (D.getKind() == Declarator::DK_Conversion) { 1062 if (!DC->isCXXRecord()) { 1063 Diag(D.getIdentifierLoc(), 1064 diag::err_conv_function_not_member); 1065 return 0; 1066 } else { 1067 bool isInvalidDecl = CheckConversionDeclarator(D, R, SC); 1068 1069 NewFD = CXXConversionDecl::Create(Context, 1070 cast<CXXRecordDecl>(DC), 1071 D.getIdentifierLoc(), Name, R, 1072 isInline, isExplicit); 1073 1074 if (isInvalidDecl) 1075 NewFD->setInvalidDecl(); 1076 } 1077 } else if (DC->isCXXRecord()) { 1078 // This is a C++ method declaration. 1079 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1080 D.getIdentifierLoc(), Name, R, 1081 (SC == FunctionDecl::Static), isInline, 1082 LastDeclarator); 1083 } else { 1084 NewFD = FunctionDecl::Create(Context, DC, 1085 D.getIdentifierLoc(), 1086 Name, R, SC, isInline, LastDeclarator, 1087 // FIXME: Move to DeclGroup... 1088 D.getDeclSpec().getSourceRange().getBegin()); 1089 } 1090 // Handle attributes. 1091 ProcessDeclAttributes(NewFD, D); 1092 1093 // Handle GNU asm-label extension (encoded as an attribute). 1094 if (Expr *E = (Expr*) D.getAsmLabel()) { 1095 // The parser guarantees this is a string. 1096 StringLiteral *SE = cast<StringLiteral>(E); 1097 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1098 SE->getByteLength()))); 1099 } 1100 1101 // Copy the parameter declarations from the declarator D to 1102 // the function declaration NewFD, if they are available. 1103 if (D.getNumTypeObjects() > 0) { 1104 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1105 1106 // Create Decl objects for each parameter, adding them to the 1107 // FunctionDecl. 1108 llvm::SmallVector<ParmVarDecl*, 16> Params; 1109 1110 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1111 // function that takes no arguments, not a function that takes a 1112 // single void argument. 1113 // We let through "const void" here because Sema::GetTypeForDeclarator 1114 // already checks for that case. 1115 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1116 FTI.ArgInfo[0].Param && 1117 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1118 // empty arg list, don't push any params. 1119 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1120 1121 // In C++, the empty parameter-type-list must be spelled "void"; a 1122 // typedef of void is not permitted. 1123 if (getLangOptions().CPlusPlus && 1124 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1125 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1126 } 1127 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1128 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1129 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1130 } 1131 1132 NewFD->setParams(&Params[0], Params.size()); 1133 } else if (R->getAsTypedefType()) { 1134 // When we're declaring a function with a typedef, as in the 1135 // following example, we'll need to synthesize (unnamed) 1136 // parameters for use in the declaration. 1137 // 1138 // @code 1139 // typedef void fn(int); 1140 // fn f; 1141 // @endcode 1142 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1143 if (!FT) { 1144 // This is a typedef of a function with no prototype, so we 1145 // don't need to do anything. 1146 } else if ((FT->getNumArgs() == 0) || 1147 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1148 FT->getArgType(0)->isVoidType())) { 1149 // This is a zero-argument function. We don't need to do anything. 1150 } else { 1151 // Synthesize a parameter for each argument type. 1152 llvm::SmallVector<ParmVarDecl*, 16> Params; 1153 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1154 ArgType != FT->arg_type_end(); ++ArgType) { 1155 Params.push_back(ParmVarDecl::Create(Context, DC, 1156 SourceLocation(), 0, 1157 *ArgType, VarDecl::None, 1158 0, 0)); 1159 } 1160 1161 NewFD->setParams(&Params[0], Params.size()); 1162 } 1163 } 1164 1165 // C++ constructors and destructors are handled by separate 1166 // routines, since they don't require any declaration merging (C++ 1167 // [class.mfct]p2) and they aren't ever pushed into scope, because 1168 // they can't be found by name lookup anyway (C++ [class.ctor]p2). 1169 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1170 return ActOnConstructorDeclarator(Constructor); 1171 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 1172 return ActOnDestructorDeclarator(Destructor); 1173 1174 // Extra checking for conversion functions, including recording 1175 // the conversion function in its class. 1176 if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(NewFD)) 1177 ActOnConversionDeclarator(Conversion); 1178 1179 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1180 if (NewFD->isOverloadedOperator() && 1181 CheckOverloadedOperatorDeclaration(NewFD)) 1182 NewFD->setInvalidDecl(); 1183 1184 // Merge the decl with the existing one if appropriate. Since C functions 1185 // are in a flat namespace, make sure we consider decls in outer scopes. 1186 if (PrevDecl && 1187 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1188 bool Redeclaration = false; 1189 1190 // If C++, determine whether NewFD is an overload of PrevDecl or 1191 // a declaration that requires merging. If it's an overload, 1192 // there's no more work to do here; we'll just add the new 1193 // function to the scope. 1194 OverloadedFunctionDecl::function_iterator MatchedDecl; 1195 if (!getLangOptions().CPlusPlus || 1196 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1197 Decl *OldDecl = PrevDecl; 1198 1199 // If PrevDecl was an overloaded function, extract the 1200 // FunctionDecl that matched. 1201 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1202 OldDecl = *MatchedDecl; 1203 1204 // NewFD and PrevDecl represent declarations that need to be 1205 // merged. 1206 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1207 1208 if (NewFD == 0) return 0; 1209 if (Redeclaration) { 1210 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1211 1212 if (OldDecl == PrevDecl) { 1213 // Remove the name binding for the previous 1214 // declaration. 1215 if (S->isDeclScope(PrevDecl)) { 1216 IdResolver.RemoveDecl(cast<NamedDecl>(PrevDecl)); 1217 S->RemoveDecl(PrevDecl); 1218 } 1219 1220 // Introduce the new binding for this declaration. 1221 IdResolver.AddDecl(NewFD); 1222 if (getLangOptions().CPlusPlus && NewFD->getParent()) 1223 NewFD->getParent()->insert(Context, NewFD); 1224 1225 // Add the redeclaration to the current scope, since we'll 1226 // be skipping PushOnScopeChains. 1227 S->AddDecl(NewFD); 1228 } else { 1229 // We need to update the OverloadedFunctionDecl with the 1230 // latest declaration of this function, so that name 1231 // lookup will always refer to the latest declaration of 1232 // this function. 1233 *MatchedDecl = NewFD; 1234 } 1235 1236 if (getLangOptions().CPlusPlus) { 1237 // Add this declaration to the current context. 1238 CurContext->addDecl(Context, NewFD, false); 1239 1240 // Check default arguments now that we have merged decls. 1241 CheckCXXDefaultArguments(NewFD); 1242 } 1243 1244 // Set the lexical context. If the declarator has a C++ 1245 // scope specifier, the lexical context will be different 1246 // from the semantic context. 1247 NewFD->setLexicalDeclContext(CurContext); 1248 1249 return NewFD; 1250 } 1251 } 1252 } 1253 New = NewFD; 1254 1255 // In C++, check default arguments now that we have merged decls. 1256 if (getLangOptions().CPlusPlus) 1257 CheckCXXDefaultArguments(NewFD); 1258 } else { 1259 // Check that there are no default arguments (C++ only). 1260 if (getLangOptions().CPlusPlus) 1261 CheckExtraCXXDefaultArguments(D); 1262 1263 if (R.getTypePtr()->isObjCInterfaceType()) { 1264 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1265 << D.getIdentifier(); 1266 InvalidDecl = true; 1267 } 1268 1269 VarDecl *NewVD; 1270 VarDecl::StorageClass SC; 1271 switch (D.getDeclSpec().getStorageClassSpec()) { 1272 default: assert(0 && "Unknown storage class!"); 1273 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1274 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1275 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1276 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1277 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1278 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1279 case DeclSpec::SCS_mutable: 1280 // mutable can only appear on non-static class members, so it's always 1281 // an error here 1282 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1283 InvalidDecl = true; 1284 SC = VarDecl::None; 1285 break; 1286 } 1287 1288 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1289 if (!II) { 1290 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1291 << Name.getAsString(); 1292 return 0; 1293 } 1294 1295 if (DC->isCXXRecord()) { 1296 assert(SC == VarDecl::Static && "Invalid storage class for member!"); 1297 // This is a static data member for a C++ class. 1298 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1299 D.getIdentifierLoc(), II, 1300 R, LastDeclarator); 1301 } else { 1302 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1303 if (S->getFnParent() == 0) { 1304 // C99 6.9p2: The storage-class specifiers auto and register shall not 1305 // appear in the declaration specifiers in an external declaration. 1306 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1307 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1308 InvalidDecl = true; 1309 } 1310 } 1311 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1312 II, R, SC, LastDeclarator, 1313 // FIXME: Move to DeclGroup... 1314 D.getDeclSpec().getSourceRange().getBegin()); 1315 NewVD->setThreadSpecified(ThreadSpecified); 1316 } 1317 // Handle attributes prior to checking for duplicates in MergeVarDecl 1318 ProcessDeclAttributes(NewVD, D); 1319 1320 // Handle GNU asm-label extension (encoded as an attribute). 1321 if (Expr *E = (Expr*) D.getAsmLabel()) { 1322 // The parser guarantees this is a string. 1323 StringLiteral *SE = cast<StringLiteral>(E); 1324 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1325 SE->getByteLength()))); 1326 } 1327 1328 // Emit an error if an address space was applied to decl with local storage. 1329 // This includes arrays of objects with address space qualifiers, but not 1330 // automatic variables that point to other address spaces. 1331 // ISO/IEC TR 18037 S5.1.2 1332 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1333 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1334 InvalidDecl = true; 1335 } 1336 // Merge the decl with the existing one if appropriate. If the decl is 1337 // in an outer scope, it isn't the same thing. 1338 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1339 NewVD = MergeVarDecl(NewVD, PrevDecl); 1340 if (NewVD == 0) return 0; 1341 } 1342 New = NewVD; 1343 } 1344 1345 // Set the lexical context. If the declarator has a C++ scope specifier, the 1346 // lexical context will be different from the semantic context. 1347 New->setLexicalDeclContext(CurContext); 1348 1349 // If this has an identifier, add it to the scope stack. 1350 if (Name) 1351 PushOnScopeChains(New, S); 1352 // If any semantic error occurred, mark the decl as invalid. 1353 if (D.getInvalidType() || InvalidDecl) 1354 New->setInvalidDecl(); 1355 1356 return New; 1357} 1358 1359void Sema::InitializerElementNotConstant(const Expr *Init) { 1360 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1361 << Init->getSourceRange(); 1362} 1363 1364bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1365 switch (Init->getStmtClass()) { 1366 default: 1367 InitializerElementNotConstant(Init); 1368 return true; 1369 case Expr::ParenExprClass: { 1370 const ParenExpr* PE = cast<ParenExpr>(Init); 1371 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1372 } 1373 case Expr::CompoundLiteralExprClass: 1374 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1375 case Expr::DeclRefExprClass: { 1376 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1377 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1378 if (VD->hasGlobalStorage()) 1379 return false; 1380 InitializerElementNotConstant(Init); 1381 return true; 1382 } 1383 if (isa<FunctionDecl>(D)) 1384 return false; 1385 InitializerElementNotConstant(Init); 1386 return true; 1387 } 1388 case Expr::MemberExprClass: { 1389 const MemberExpr *M = cast<MemberExpr>(Init); 1390 if (M->isArrow()) 1391 return CheckAddressConstantExpression(M->getBase()); 1392 return CheckAddressConstantExpressionLValue(M->getBase()); 1393 } 1394 case Expr::ArraySubscriptExprClass: { 1395 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1396 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1397 return CheckAddressConstantExpression(ASE->getBase()) || 1398 CheckArithmeticConstantExpression(ASE->getIdx()); 1399 } 1400 case Expr::StringLiteralClass: 1401 case Expr::PredefinedExprClass: 1402 return false; 1403 case Expr::UnaryOperatorClass: { 1404 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1405 1406 // C99 6.6p9 1407 if (Exp->getOpcode() == UnaryOperator::Deref) 1408 return CheckAddressConstantExpression(Exp->getSubExpr()); 1409 1410 InitializerElementNotConstant(Init); 1411 return true; 1412 } 1413 } 1414} 1415 1416bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1417 switch (Init->getStmtClass()) { 1418 default: 1419 InitializerElementNotConstant(Init); 1420 return true; 1421 case Expr::ParenExprClass: 1422 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1423 case Expr::StringLiteralClass: 1424 case Expr::ObjCStringLiteralClass: 1425 return false; 1426 case Expr::CallExprClass: 1427 case Expr::CXXOperatorCallExprClass: 1428 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1429 if (cast<CallExpr>(Init)->isBuiltinCall() == 1430 Builtin::BI__builtin___CFStringMakeConstantString) 1431 return false; 1432 1433 InitializerElementNotConstant(Init); 1434 return true; 1435 1436 case Expr::UnaryOperatorClass: { 1437 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1438 1439 // C99 6.6p9 1440 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1441 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1442 1443 if (Exp->getOpcode() == UnaryOperator::Extension) 1444 return CheckAddressConstantExpression(Exp->getSubExpr()); 1445 1446 InitializerElementNotConstant(Init); 1447 return true; 1448 } 1449 case Expr::BinaryOperatorClass: { 1450 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1451 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1452 1453 Expr *PExp = Exp->getLHS(); 1454 Expr *IExp = Exp->getRHS(); 1455 if (IExp->getType()->isPointerType()) 1456 std::swap(PExp, IExp); 1457 1458 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1459 return CheckAddressConstantExpression(PExp) || 1460 CheckArithmeticConstantExpression(IExp); 1461 } 1462 case Expr::ImplicitCastExprClass: 1463 case Expr::CStyleCastExprClass: { 1464 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1465 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1466 // Check for implicit promotion 1467 if (SubExpr->getType()->isFunctionType() || 1468 SubExpr->getType()->isArrayType()) 1469 return CheckAddressConstantExpressionLValue(SubExpr); 1470 } 1471 1472 // Check for pointer->pointer cast 1473 if (SubExpr->getType()->isPointerType()) 1474 return CheckAddressConstantExpression(SubExpr); 1475 1476 if (SubExpr->getType()->isIntegralType()) { 1477 // Check for the special-case of a pointer->int->pointer cast; 1478 // this isn't standard, but some code requires it. See 1479 // PR2720 for an example. 1480 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1481 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1482 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1483 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1484 if (IntWidth >= PointerWidth) { 1485 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1486 } 1487 } 1488 } 1489 } 1490 if (SubExpr->getType()->isArithmeticType()) { 1491 return CheckArithmeticConstantExpression(SubExpr); 1492 } 1493 1494 InitializerElementNotConstant(Init); 1495 return true; 1496 } 1497 case Expr::ConditionalOperatorClass: { 1498 // FIXME: Should we pedwarn here? 1499 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1500 if (!Exp->getCond()->getType()->isArithmeticType()) { 1501 InitializerElementNotConstant(Init); 1502 return true; 1503 } 1504 if (CheckArithmeticConstantExpression(Exp->getCond())) 1505 return true; 1506 if (Exp->getLHS() && 1507 CheckAddressConstantExpression(Exp->getLHS())) 1508 return true; 1509 return CheckAddressConstantExpression(Exp->getRHS()); 1510 } 1511 case Expr::AddrLabelExprClass: 1512 return false; 1513 } 1514} 1515 1516static const Expr* FindExpressionBaseAddress(const Expr* E); 1517 1518static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1519 switch (E->getStmtClass()) { 1520 default: 1521 return E; 1522 case Expr::ParenExprClass: { 1523 const ParenExpr* PE = cast<ParenExpr>(E); 1524 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1525 } 1526 case Expr::MemberExprClass: { 1527 const MemberExpr *M = cast<MemberExpr>(E); 1528 if (M->isArrow()) 1529 return FindExpressionBaseAddress(M->getBase()); 1530 return FindExpressionBaseAddressLValue(M->getBase()); 1531 } 1532 case Expr::ArraySubscriptExprClass: { 1533 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1534 return FindExpressionBaseAddress(ASE->getBase()); 1535 } 1536 case Expr::UnaryOperatorClass: { 1537 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1538 1539 if (Exp->getOpcode() == UnaryOperator::Deref) 1540 return FindExpressionBaseAddress(Exp->getSubExpr()); 1541 1542 return E; 1543 } 1544 } 1545} 1546 1547static const Expr* FindExpressionBaseAddress(const Expr* E) { 1548 switch (E->getStmtClass()) { 1549 default: 1550 return E; 1551 case Expr::ParenExprClass: { 1552 const ParenExpr* PE = cast<ParenExpr>(E); 1553 return FindExpressionBaseAddress(PE->getSubExpr()); 1554 } 1555 case Expr::UnaryOperatorClass: { 1556 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1557 1558 // C99 6.6p9 1559 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1560 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1561 1562 if (Exp->getOpcode() == UnaryOperator::Extension) 1563 return FindExpressionBaseAddress(Exp->getSubExpr()); 1564 1565 return E; 1566 } 1567 case Expr::BinaryOperatorClass: { 1568 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1569 1570 Expr *PExp = Exp->getLHS(); 1571 Expr *IExp = Exp->getRHS(); 1572 if (IExp->getType()->isPointerType()) 1573 std::swap(PExp, IExp); 1574 1575 return FindExpressionBaseAddress(PExp); 1576 } 1577 case Expr::ImplicitCastExprClass: { 1578 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1579 1580 // Check for implicit promotion 1581 if (SubExpr->getType()->isFunctionType() || 1582 SubExpr->getType()->isArrayType()) 1583 return FindExpressionBaseAddressLValue(SubExpr); 1584 1585 // Check for pointer->pointer cast 1586 if (SubExpr->getType()->isPointerType()) 1587 return FindExpressionBaseAddress(SubExpr); 1588 1589 // We assume that we have an arithmetic expression here; 1590 // if we don't, we'll figure it out later 1591 return 0; 1592 } 1593 case Expr::CStyleCastExprClass: { 1594 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1595 1596 // Check for pointer->pointer cast 1597 if (SubExpr->getType()->isPointerType()) 1598 return FindExpressionBaseAddress(SubExpr); 1599 1600 // We assume that we have an arithmetic expression here; 1601 // if we don't, we'll figure it out later 1602 return 0; 1603 } 1604 } 1605} 1606 1607bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1608 switch (Init->getStmtClass()) { 1609 default: 1610 InitializerElementNotConstant(Init); 1611 return true; 1612 case Expr::ParenExprClass: { 1613 const ParenExpr* PE = cast<ParenExpr>(Init); 1614 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1615 } 1616 case Expr::FloatingLiteralClass: 1617 case Expr::IntegerLiteralClass: 1618 case Expr::CharacterLiteralClass: 1619 case Expr::ImaginaryLiteralClass: 1620 case Expr::TypesCompatibleExprClass: 1621 case Expr::CXXBoolLiteralExprClass: 1622 return false; 1623 case Expr::CallExprClass: 1624 case Expr::CXXOperatorCallExprClass: { 1625 const CallExpr *CE = cast<CallExpr>(Init); 1626 1627 // Allow any constant foldable calls to builtins. 1628 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1629 return false; 1630 1631 InitializerElementNotConstant(Init); 1632 return true; 1633 } 1634 case Expr::DeclRefExprClass: { 1635 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1636 if (isa<EnumConstantDecl>(D)) 1637 return false; 1638 InitializerElementNotConstant(Init); 1639 return true; 1640 } 1641 case Expr::CompoundLiteralExprClass: 1642 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1643 // but vectors are allowed to be magic. 1644 if (Init->getType()->isVectorType()) 1645 return false; 1646 InitializerElementNotConstant(Init); 1647 return true; 1648 case Expr::UnaryOperatorClass: { 1649 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1650 1651 switch (Exp->getOpcode()) { 1652 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1653 // See C99 6.6p3. 1654 default: 1655 InitializerElementNotConstant(Init); 1656 return true; 1657 case UnaryOperator::OffsetOf: 1658 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1659 return false; 1660 InitializerElementNotConstant(Init); 1661 return true; 1662 case UnaryOperator::Extension: 1663 case UnaryOperator::LNot: 1664 case UnaryOperator::Plus: 1665 case UnaryOperator::Minus: 1666 case UnaryOperator::Not: 1667 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1668 } 1669 } 1670 case Expr::SizeOfAlignOfExprClass: { 1671 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 1672 // Special check for void types, which are allowed as an extension 1673 if (Exp->getTypeOfArgument()->isVoidType()) 1674 return false; 1675 // alignof always evaluates to a constant. 1676 // FIXME: is sizeof(int[3.0]) a constant expression? 1677 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 1678 InitializerElementNotConstant(Init); 1679 return true; 1680 } 1681 return false; 1682 } 1683 case Expr::BinaryOperatorClass: { 1684 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1685 1686 if (Exp->getLHS()->getType()->isArithmeticType() && 1687 Exp->getRHS()->getType()->isArithmeticType()) { 1688 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1689 CheckArithmeticConstantExpression(Exp->getRHS()); 1690 } 1691 1692 if (Exp->getLHS()->getType()->isPointerType() && 1693 Exp->getRHS()->getType()->isPointerType()) { 1694 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1695 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1696 1697 // Only allow a null (constant integer) base; we could 1698 // allow some additional cases if necessary, but this 1699 // is sufficient to cover offsetof-like constructs. 1700 if (!LHSBase && !RHSBase) { 1701 return CheckAddressConstantExpression(Exp->getLHS()) || 1702 CheckAddressConstantExpression(Exp->getRHS()); 1703 } 1704 } 1705 1706 InitializerElementNotConstant(Init); 1707 return true; 1708 } 1709 case Expr::ImplicitCastExprClass: 1710 case Expr::CStyleCastExprClass: { 1711 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1712 if (SubExpr->getType()->isArithmeticType()) 1713 return CheckArithmeticConstantExpression(SubExpr); 1714 1715 if (SubExpr->getType()->isPointerType()) { 1716 const Expr* Base = FindExpressionBaseAddress(SubExpr); 1717 // If the pointer has a null base, this is an offsetof-like construct 1718 if (!Base) 1719 return CheckAddressConstantExpression(SubExpr); 1720 } 1721 1722 InitializerElementNotConstant(Init); 1723 return true; 1724 } 1725 case Expr::ConditionalOperatorClass: { 1726 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1727 1728 // If GNU extensions are disabled, we require all operands to be arithmetic 1729 // constant expressions. 1730 if (getLangOptions().NoExtensions) { 1731 return CheckArithmeticConstantExpression(Exp->getCond()) || 1732 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 1733 CheckArithmeticConstantExpression(Exp->getRHS()); 1734 } 1735 1736 // Otherwise, we have to emulate some of the behavior of fold here. 1737 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 1738 // because it can constant fold things away. To retain compatibility with 1739 // GCC code, we see if we can fold the condition to a constant (which we 1740 // should always be able to do in theory). If so, we only require the 1741 // specified arm of the conditional to be a constant. This is a horrible 1742 // hack, but is require by real world code that uses __builtin_constant_p. 1743 APValue Val; 1744 if (!Exp->getCond()->Evaluate(Val, Context)) { 1745 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 1746 // won't be able to either. Use it to emit the diagnostic though. 1747 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 1748 assert(Res && "Evaluate couldn't evaluate this constant?"); 1749 return Res; 1750 } 1751 1752 // Verify that the side following the condition is also a constant. 1753 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 1754 if (Val.getInt() == 0) 1755 std::swap(TrueSide, FalseSide); 1756 1757 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 1758 return true; 1759 1760 // Okay, the evaluated side evaluates to a constant, so we accept this. 1761 // Check to see if the other side is obviously not a constant. If so, 1762 // emit a warning that this is a GNU extension. 1763 if (FalseSide && !FalseSide->isEvaluatable(Context)) 1764 Diag(Init->getExprLoc(), 1765 diag::ext_typecheck_expression_not_constant_but_accepted) 1766 << FalseSide->getSourceRange(); 1767 return false; 1768 } 1769 } 1770} 1771 1772bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1773 Expr::EvalResult Result; 1774 1775 Init = Init->IgnoreParens(); 1776 1777 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 1778 return false; 1779 1780 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1781 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1782 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1783 1784 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 1785 return CheckForConstantInitializer(e->getInitializer(), DclT); 1786 1787 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1788 unsigned numInits = Exp->getNumInits(); 1789 for (unsigned i = 0; i < numInits; i++) { 1790 // FIXME: Need to get the type of the declaration for C++, 1791 // because it could be a reference? 1792 if (CheckForConstantInitializer(Exp->getInit(i), 1793 Exp->getInit(i)->getType())) 1794 return true; 1795 } 1796 return false; 1797 } 1798 1799 // FIXME: We can probably remove some of this code below, now that 1800 // Expr::Evaluate is doing the heavy lifting for scalars. 1801 1802 if (Init->isNullPointerConstant(Context)) 1803 return false; 1804 if (Init->getType()->isArithmeticType()) { 1805 QualType InitTy = Context.getCanonicalType(Init->getType()) 1806 .getUnqualifiedType(); 1807 if (InitTy == Context.BoolTy) { 1808 // Special handling for pointers implicitly cast to bool; 1809 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1810 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1811 Expr* SubE = ICE->getSubExpr(); 1812 if (SubE->getType()->isPointerType() || 1813 SubE->getType()->isArrayType() || 1814 SubE->getType()->isFunctionType()) { 1815 return CheckAddressConstantExpression(Init); 1816 } 1817 } 1818 } else if (InitTy->isIntegralType()) { 1819 Expr* SubE = 0; 1820 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1821 SubE = CE->getSubExpr(); 1822 // Special check for pointer cast to int; we allow as an extension 1823 // an address constant cast to an integer if the integer 1824 // is of an appropriate width (this sort of code is apparently used 1825 // in some places). 1826 // FIXME: Add pedwarn? 1827 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1828 if (SubE && (SubE->getType()->isPointerType() || 1829 SubE->getType()->isArrayType() || 1830 SubE->getType()->isFunctionType())) { 1831 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1832 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1833 if (IntWidth >= PointerWidth) 1834 return CheckAddressConstantExpression(Init); 1835 } 1836 } 1837 1838 return CheckArithmeticConstantExpression(Init); 1839 } 1840 1841 if (Init->getType()->isPointerType()) 1842 return CheckAddressConstantExpression(Init); 1843 1844 // An array type at the top level that isn't an init-list must 1845 // be a string literal 1846 if (Init->getType()->isArrayType()) 1847 return false; 1848 1849 if (Init->getType()->isFunctionType()) 1850 return false; 1851 1852 // Allow block exprs at top level. 1853 if (Init->getType()->isBlockPointerType()) 1854 return false; 1855 1856 InitializerElementNotConstant(Init); 1857 return true; 1858} 1859 1860void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1861 Decl *RealDecl = static_cast<Decl *>(dcl); 1862 Expr *Init = static_cast<Expr *>(init); 1863 assert(Init && "missing initializer"); 1864 1865 // If there is no declaration, there was an error parsing it. Just ignore 1866 // the initializer. 1867 if (RealDecl == 0) { 1868 delete Init; 1869 return; 1870 } 1871 1872 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1873 if (!VDecl) { 1874 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1875 diag::err_illegal_initializer); 1876 RealDecl->setInvalidDecl(); 1877 return; 1878 } 1879 // Get the decls type and save a reference for later, since 1880 // CheckInitializerTypes may change it. 1881 QualType DclT = VDecl->getType(), SavT = DclT; 1882 if (VDecl->isBlockVarDecl()) { 1883 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1884 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1885 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1886 VDecl->setInvalidDecl(); 1887 } else if (!VDecl->isInvalidDecl()) { 1888 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 1889 VDecl->getDeclName())) 1890 VDecl->setInvalidDecl(); 1891 1892 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 1893 if (!getLangOptions().CPlusPlus) { 1894 if (SC == VarDecl::Static) // C99 6.7.8p4. 1895 CheckForConstantInitializer(Init, DclT); 1896 } 1897 } 1898 } else if (VDecl->isFileVarDecl()) { 1899 if (VDecl->getStorageClass() == VarDecl::Extern) 1900 Diag(VDecl->getLocation(), diag::warn_extern_init); 1901 if (!VDecl->isInvalidDecl()) 1902 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 1903 VDecl->getDeclName())) 1904 VDecl->setInvalidDecl(); 1905 1906 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 1907 if (!getLangOptions().CPlusPlus) { 1908 // C99 6.7.8p4. All file scoped initializers need to be constant. 1909 CheckForConstantInitializer(Init, DclT); 1910 } 1911 } 1912 // If the type changed, it means we had an incomplete type that was 1913 // completed by the initializer. For example: 1914 // int ary[] = { 1, 3, 5 }; 1915 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1916 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1917 VDecl->setType(DclT); 1918 Init->setType(DclT); 1919 } 1920 1921 // Attach the initializer to the decl. 1922 VDecl->setInit(Init); 1923 return; 1924} 1925 1926void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 1927 Decl *RealDecl = static_cast<Decl *>(dcl); 1928 1929 // If there is no declaration, there was an error parsing it. Just ignore it. 1930 if (RealDecl == 0) 1931 return; 1932 1933 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 1934 QualType Type = Var->getType(); 1935 // C++ [dcl.init.ref]p3: 1936 // The initializer can be omitted for a reference only in a 1937 // parameter declaration (8.3.5), in the declaration of a 1938 // function return type, in the declaration of a class member 1939 // within its class declaration (9.2), and where the extern 1940 // specifier is explicitly used. 1941 if (Type->isReferenceType() && Var->getStorageClass() != VarDecl::Extern) { 1942 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 1943 << Var->getDeclName() 1944 << SourceRange(Var->getLocation(), Var->getLocation()); 1945 Var->setInvalidDecl(); 1946 return; 1947 } 1948 1949 // C++ [dcl.init]p9: 1950 // 1951 // If no initializer is specified for an object, and the object 1952 // is of (possibly cv-qualified) non-POD class type (or array 1953 // thereof), the object shall be default-initialized; if the 1954 // object is of const-qualified type, the underlying class type 1955 // shall have a user-declared default constructor. 1956 if (getLangOptions().CPlusPlus) { 1957 QualType InitType = Type; 1958 if (const ArrayType *Array = Context.getAsArrayType(Type)) 1959 InitType = Array->getElementType(); 1960 if (InitType->isRecordType()) { 1961 const CXXConstructorDecl *Constructor 1962 = PerformInitializationByConstructor(InitType, 0, 0, 1963 Var->getLocation(), 1964 SourceRange(Var->getLocation(), 1965 Var->getLocation()), 1966 Var->getDeclName(), 1967 IK_Default); 1968 if (!Constructor) 1969 Var->setInvalidDecl(); 1970 } 1971 } 1972 1973#if 0 1974 // FIXME: Temporarily disabled because we are not properly parsing 1975 // linkage specifications on declarations, e.g., 1976 // 1977 // extern "C" const CGPoint CGPointerZero; 1978 // 1979 // C++ [dcl.init]p9: 1980 // 1981 // If no initializer is specified for an object, and the 1982 // object is of (possibly cv-qualified) non-POD class type (or 1983 // array thereof), the object shall be default-initialized; if 1984 // the object is of const-qualified type, the underlying class 1985 // type shall have a user-declared default 1986 // constructor. Otherwise, if no initializer is specified for 1987 // an object, the object and its subobjects, if any, have an 1988 // indeterminate initial value; if the object or any of its 1989 // subobjects are of const-qualified type, the program is 1990 // ill-formed. 1991 // 1992 // This isn't technically an error in C, so we don't diagnose it. 1993 // 1994 // FIXME: Actually perform the POD/user-defined default 1995 // constructor check. 1996 if (getLangOptions().CPlusPlus && 1997 Context.getCanonicalType(Type).isConstQualified() && 1998 Var->getStorageClass() != VarDecl::Extern) 1999 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2000 << Var->getName() 2001 << SourceRange(Var->getLocation(), Var->getLocation()); 2002#endif 2003 } 2004} 2005 2006/// The declarators are chained together backwards, reverse the list. 2007Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2008 // Often we have single declarators, handle them quickly. 2009 Decl *GroupDecl = static_cast<Decl*>(group); 2010 if (GroupDecl == 0) 2011 return 0; 2012 2013 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2014 ScopedDecl *NewGroup = 0; 2015 if (Group->getNextDeclarator() == 0) 2016 NewGroup = Group; 2017 else { // reverse the list. 2018 while (Group) { 2019 ScopedDecl *Next = Group->getNextDeclarator(); 2020 Group->setNextDeclarator(NewGroup); 2021 NewGroup = Group; 2022 Group = Next; 2023 } 2024 } 2025 // Perform semantic analysis that depends on having fully processed both 2026 // the declarator and initializer. 2027 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2028 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2029 if (!IDecl) 2030 continue; 2031 QualType T = IDecl->getType(); 2032 2033 if (T->isVariableArrayType()) { 2034 const VariableArrayType *VAT = 2035 cast<VariableArrayType>(T.getUnqualifiedType()); 2036 2037 // FIXME: This won't give the correct result for 2038 // int a[10][n]; 2039 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2040 if (IDecl->isFileVarDecl()) { 2041 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2042 SizeRange; 2043 2044 IDecl->setInvalidDecl(); 2045 } else { 2046 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2047 // static storage duration, it shall not have a variable length array. 2048 if (IDecl->getStorageClass() == VarDecl::Static) { 2049 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2050 << SizeRange; 2051 IDecl->setInvalidDecl(); 2052 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2053 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2054 << SizeRange; 2055 IDecl->setInvalidDecl(); 2056 } 2057 } 2058 } else if (T->isVariablyModifiedType()) { 2059 if (IDecl->isFileVarDecl()) { 2060 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2061 IDecl->setInvalidDecl(); 2062 } else { 2063 if (IDecl->getStorageClass() == VarDecl::Extern) { 2064 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2065 IDecl->setInvalidDecl(); 2066 } 2067 } 2068 } 2069 2070 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2071 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2072 if (IDecl->isBlockVarDecl() && 2073 IDecl->getStorageClass() != VarDecl::Extern) { 2074 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2075 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2076 IDecl->setInvalidDecl(); 2077 } 2078 } 2079 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2080 // object that has file scope without an initializer, and without a 2081 // storage-class specifier or with the storage-class specifier "static", 2082 // constitutes a tentative definition. Note: A tentative definition with 2083 // external linkage is valid (C99 6.2.2p5). 2084 if (isTentativeDefinition(IDecl)) { 2085 if (T->isIncompleteArrayType()) { 2086 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2087 // array to be completed. Don't issue a diagnostic. 2088 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2089 // C99 6.9.2p3: If the declaration of an identifier for an object is 2090 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2091 // declared type shall not be an incomplete type. 2092 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2093 IDecl->setInvalidDecl(); 2094 } 2095 } 2096 if (IDecl->isFileVarDecl()) 2097 CheckForFileScopedRedefinitions(S, IDecl); 2098 } 2099 return NewGroup; 2100} 2101 2102/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2103/// to introduce parameters into function prototype scope. 2104Sema::DeclTy * 2105Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2106 // FIXME: disallow CXXScopeSpec for param declarators. 2107 const DeclSpec &DS = D.getDeclSpec(); 2108 2109 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2110 VarDecl::StorageClass StorageClass = VarDecl::None; 2111 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2112 StorageClass = VarDecl::Register; 2113 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2114 Diag(DS.getStorageClassSpecLoc(), 2115 diag::err_invalid_storage_class_in_func_decl); 2116 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2117 } 2118 if (DS.isThreadSpecified()) { 2119 Diag(DS.getThreadSpecLoc(), 2120 diag::err_invalid_storage_class_in_func_decl); 2121 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2122 } 2123 2124 // Check that there are no default arguments inside the type of this 2125 // parameter (C++ only). 2126 if (getLangOptions().CPlusPlus) 2127 CheckExtraCXXDefaultArguments(D); 2128 2129 // In this context, we *do not* check D.getInvalidType(). If the declarator 2130 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2131 // though it will not reflect the user specified type. 2132 QualType parmDeclType = GetTypeForDeclarator(D, S); 2133 2134 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2135 2136 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2137 // Can this happen for params? We already checked that they don't conflict 2138 // among each other. Here they can only shadow globals, which is ok. 2139 IdentifierInfo *II = D.getIdentifier(); 2140 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2141 if (PrevDecl->isTemplateParameter()) { 2142 // Maybe we will complain about the shadowed template parameter. 2143 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2144 // Just pretend that we didn't see the previous declaration. 2145 PrevDecl = 0; 2146 } else if (S->isDeclScope(PrevDecl)) { 2147 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2148 2149 // Recover by removing the name 2150 II = 0; 2151 D.SetIdentifier(0, D.getIdentifierLoc()); 2152 } 2153 } 2154 2155 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2156 // Doing the promotion here has a win and a loss. The win is the type for 2157 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2158 // code generator). The loss is the orginal type isn't preserved. For example: 2159 // 2160 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2161 // int blockvardecl[5]; 2162 // sizeof(parmvardecl); // size == 4 2163 // sizeof(blockvardecl); // size == 20 2164 // } 2165 // 2166 // For expressions, all implicit conversions are captured using the 2167 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2168 // 2169 // FIXME: If a source translation tool needs to see the original type, then 2170 // we need to consider storing both types (in ParmVarDecl)... 2171 // 2172 if (parmDeclType->isArrayType()) { 2173 // int x[restrict 4] -> int *restrict 2174 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2175 } else if (parmDeclType->isFunctionType()) 2176 parmDeclType = Context.getPointerType(parmDeclType); 2177 2178 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2179 D.getIdentifierLoc(), II, 2180 parmDeclType, StorageClass, 2181 0, 0); 2182 2183 if (D.getInvalidType()) 2184 New->setInvalidDecl(); 2185 2186 // Add the parameter declaration into this scope. 2187 S->AddDecl(New); 2188 if (II) 2189 IdResolver.AddDecl(New); 2190 2191 ProcessDeclAttributes(New, D); 2192 return New; 2193 2194} 2195 2196Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2197 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2198 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2199 "Not a function declarator!"); 2200 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2201 2202 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2203 // for a K&R function. 2204 if (!FTI.hasPrototype) { 2205 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2206 if (FTI.ArgInfo[i].Param == 0) { 2207 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2208 << FTI.ArgInfo[i].Ident; 2209 // Implicitly declare the argument as type 'int' for lack of a better 2210 // type. 2211 DeclSpec DS; 2212 const char* PrevSpec; // unused 2213 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2214 PrevSpec); 2215 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2216 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2217 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2218 } 2219 } 2220 } else { 2221 // FIXME: Diagnose arguments without names in C. 2222 } 2223 2224 Scope *GlobalScope = FnBodyScope->getParent(); 2225 2226 return ActOnStartOfFunctionDef(FnBodyScope, 2227 ActOnDeclarator(GlobalScope, D, 0)); 2228} 2229 2230Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2231 Decl *decl = static_cast<Decl*>(D); 2232 FunctionDecl *FD = cast<FunctionDecl>(decl); 2233 2234 // See if this is a redefinition. 2235 const FunctionDecl *Definition; 2236 if (FD->getBody(Definition)) { 2237 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2238 Diag(Definition->getLocation(), diag::note_previous_definition); 2239 } 2240 2241 PushDeclContext(FnBodyScope, FD); 2242 2243 // Check the validity of our function parameters 2244 CheckParmsForFunctionDef(FD); 2245 2246 // Introduce our parameters into the function scope 2247 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2248 ParmVarDecl *Param = FD->getParamDecl(p); 2249 // If this has an identifier, add it to the scope stack. 2250 if (Param->getIdentifier()) 2251 PushOnScopeChains(Param, FnBodyScope); 2252 } 2253 2254 return FD; 2255} 2256 2257Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 2258 Decl *dcl = static_cast<Decl *>(D); 2259 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2260 FD->setBody((Stmt*)Body); 2261 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2262 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2263 MD->setBody((Stmt*)Body); 2264 } else 2265 return 0; 2266 PopDeclContext(); 2267 // Verify and clean out per-function state. 2268 2269 // Check goto/label use. 2270 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2271 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2272 // Verify that we have no forward references left. If so, there was a goto 2273 // or address of a label taken, but no definition of it. Label fwd 2274 // definitions are indicated with a null substmt. 2275 if (I->second->getSubStmt() == 0) { 2276 LabelStmt *L = I->second; 2277 // Emit error. 2278 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2279 2280 // At this point, we have gotos that use the bogus label. Stitch it into 2281 // the function body so that they aren't leaked and that the AST is well 2282 // formed. 2283 if (Body) { 2284 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2285 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 2286 } else { 2287 // The whole function wasn't parsed correctly, just delete this. 2288 delete L; 2289 } 2290 } 2291 } 2292 LabelMap.clear(); 2293 2294 return D; 2295} 2296 2297/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2298/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2299ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2300 IdentifierInfo &II, Scope *S) { 2301 // Extension in C99. Legal in C90, but warn about it. 2302 if (getLangOptions().C99) 2303 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2304 else 2305 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2306 2307 // FIXME: handle stuff like: 2308 // void foo() { extern float X(); } 2309 // void bar() { X(); } <-- implicit decl for X in another scope. 2310 2311 // Set a Declarator for the implicit definition: int foo(); 2312 const char *Dummy; 2313 DeclSpec DS; 2314 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2315 Error = Error; // Silence warning. 2316 assert(!Error && "Error setting up implicit decl!"); 2317 Declarator D(DS, Declarator::BlockContext); 2318 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2319 D.SetIdentifier(&II, Loc); 2320 2321 // Insert this function into translation-unit scope. 2322 2323 DeclContext *PrevDC = CurContext; 2324 CurContext = Context.getTranslationUnitDecl(); 2325 2326 FunctionDecl *FD = 2327 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2328 FD->setImplicit(); 2329 2330 CurContext = PrevDC; 2331 2332 return FD; 2333} 2334 2335 2336TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2337 ScopedDecl *LastDeclarator) { 2338 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2339 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2340 2341 // Scope manipulation handled by caller. 2342 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2343 D.getIdentifierLoc(), 2344 D.getIdentifier(), 2345 T, LastDeclarator); 2346 if (D.getInvalidType()) 2347 NewTD->setInvalidDecl(); 2348 return NewTD; 2349} 2350 2351/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2352/// former case, Name will be non-null. In the later case, Name will be null. 2353/// TagType indicates what kind of tag this is. TK indicates whether this is a 2354/// reference/declaration/definition of a tag. 2355Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2356 SourceLocation KWLoc, const CXXScopeSpec &SS, 2357 IdentifierInfo *Name, SourceLocation NameLoc, 2358 AttributeList *Attr) { 2359 // If this is a use of an existing tag, it must have a name. 2360 assert((Name != 0 || TK == TK_Definition) && 2361 "Nameless record must be a definition!"); 2362 2363 TagDecl::TagKind Kind; 2364 switch (TagType) { 2365 default: assert(0 && "Unknown tag type!"); 2366 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2367 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2368 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2369 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2370 } 2371 2372 // Two code paths: a new one for structs/unions/classes where we create 2373 // separate decls for forward declarations, and an old (eventually to 2374 // be removed) code path for enums. 2375 if (Kind != TagDecl::TK_enum) 2376 return ActOnTagStruct(S, Kind, TK, KWLoc, SS, Name, NameLoc, Attr); 2377 2378 DeclContext *DC = CurContext; 2379 ScopedDecl *PrevDecl = 0; 2380 2381 if (Name && SS.isNotEmpty()) { 2382 // We have a nested-name tag ('struct foo::bar'). 2383 2384 // Check for invalid 'foo::'. 2385 if (SS.isInvalid()) { 2386 Name = 0; 2387 goto CreateNewDecl; 2388 } 2389 2390 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2391 // Look-up name inside 'foo::'. 2392 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2393 2394 // A tag 'foo::bar' must already exist. 2395 if (PrevDecl == 0) { 2396 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2397 Name = 0; 2398 goto CreateNewDecl; 2399 } 2400 } else { 2401 // If this is a named struct, check to see if there was a previous forward 2402 // declaration or definition. 2403 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2404 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2405 } 2406 2407 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2408 // Maybe we will complain about the shadowed template parameter. 2409 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2410 // Just pretend that we didn't see the previous declaration. 2411 PrevDecl = 0; 2412 } 2413 2414 if (PrevDecl) { 2415 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2416 "unexpected Decl type"); 2417 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2418 // If this is a use of a previous tag, or if the tag is already declared 2419 // in the same scope (so that the definition/declaration completes or 2420 // rementions the tag), reuse the decl. 2421 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2422 // Make sure that this wasn't declared as an enum and now used as a 2423 // struct or something similar. 2424 if (PrevTagDecl->getTagKind() != Kind) { 2425 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2426 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2427 // Recover by making this an anonymous redefinition. 2428 Name = 0; 2429 PrevDecl = 0; 2430 } else { 2431 // If this is a use or a forward declaration, we're good. 2432 if (TK != TK_Definition) 2433 return PrevDecl; 2434 2435 // Diagnose attempts to redefine a tag. 2436 if (PrevTagDecl->isDefinition()) { 2437 Diag(NameLoc, diag::err_redefinition) << Name; 2438 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2439 // If this is a redefinition, recover by making this struct be 2440 // anonymous, which will make any later references get the previous 2441 // definition. 2442 Name = 0; 2443 } else { 2444 // Okay, this is definition of a previously declared or referenced 2445 // tag. Move the location of the decl to be the definition site. 2446 PrevDecl->setLocation(NameLoc); 2447 return PrevDecl; 2448 } 2449 } 2450 } 2451 // If we get here, this is a definition of a new struct type in a nested 2452 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 2453 // type. 2454 } else { 2455 // PrevDecl is a namespace. 2456 if (isDeclInScope(PrevDecl, DC, S)) { 2457 // The tag name clashes with a namespace name, issue an error and 2458 // recover by making this tag be anonymous. 2459 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2460 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2461 Name = 0; 2462 } 2463 } 2464 } 2465 2466 CreateNewDecl: 2467 2468 // If there is an identifier, use the location of the identifier as the 2469 // location of the decl, otherwise use the location of the struct/union 2470 // keyword. 2471 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2472 2473 // Otherwise, if this is the first time we've seen this tag, create the decl. 2474 TagDecl *New; 2475 if (Kind == TagDecl::TK_enum) { 2476 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2477 // enum X { A, B, C } D; D should chain to X. 2478 New = EnumDecl::Create(Context, DC, Loc, Name, 0); 2479 // If this is an undefined enum, warn. 2480 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2481 } else { 2482 // struct/union/class 2483 2484 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2485 // struct X { int A; } D; D should chain to X. 2486 if (getLangOptions().CPlusPlus) 2487 // FIXME: Look for a way to use RecordDecl for simple structs. 2488 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name); 2489 else 2490 New = RecordDecl::Create(Context, Kind, DC, Loc, Name); 2491 } 2492 2493 // If this has an identifier, add it to the scope stack. 2494 if (Name) { 2495 // The scope passed in may not be a decl scope. Zip up the scope tree until 2496 // we find one that is. 2497 while ((S->getFlags() & Scope::DeclScope) == 0) 2498 S = S->getParent(); 2499 2500 // Add it to the decl chain. 2501 PushOnScopeChains(New, S); 2502 } 2503 2504 if (Attr) 2505 ProcessDeclAttributeList(New, Attr); 2506 2507 // Set the lexical context. If the tag has a C++ scope specifier, the 2508 // lexical context will be different from the semantic context. 2509 New->setLexicalDeclContext(CurContext); 2510 2511 return New; 2512} 2513 2514/// ActOnTagStruct - New "ActOnTag" logic for structs/unions/classes. Unlike 2515/// the logic for enums, we create separate decls for forward declarations. 2516/// This is called by ActOnTag, but eventually will replace its logic. 2517Sema::DeclTy *Sema::ActOnTagStruct(Scope *S, TagDecl::TagKind Kind, TagKind TK, 2518 SourceLocation KWLoc, const CXXScopeSpec &SS, 2519 IdentifierInfo *Name, SourceLocation NameLoc, 2520 AttributeList *Attr) { 2521 DeclContext *DC = CurContext; 2522 ScopedDecl *PrevDecl = 0; 2523 2524 if (Name && SS.isNotEmpty()) { 2525 // We have a nested-name tag ('struct foo::bar'). 2526 2527 // Check for invalid 'foo::'. 2528 if (SS.isInvalid()) { 2529 Name = 0; 2530 goto CreateNewDecl; 2531 } 2532 2533 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2534 // Look-up name inside 'foo::'. 2535 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2536 2537 // A tag 'foo::bar' must already exist. 2538 if (PrevDecl == 0) { 2539 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2540 Name = 0; 2541 goto CreateNewDecl; 2542 } 2543 } else { 2544 // If this is a named struct, check to see if there was a previous forward 2545 // declaration or definition. 2546 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2547 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2548 } 2549 2550 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2551 // Maybe we will complain about the shadowed template parameter. 2552 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2553 // Just pretend that we didn't see the previous declaration. 2554 PrevDecl = 0; 2555 } 2556 2557 if (PrevDecl) { 2558 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2559 "unexpected Decl type"); 2560 2561 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2562 // If this is a use of a previous tag, or if the tag is already declared 2563 // in the same scope (so that the definition/declaration completes or 2564 // rementions the tag), reuse the decl. 2565 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2566 // Make sure that this wasn't declared as an enum and now used as a 2567 // struct or something similar. 2568 if (PrevTagDecl->getTagKind() != Kind) { 2569 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2570 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2571 // Recover by making this an anonymous redefinition. 2572 Name = 0; 2573 PrevDecl = 0; 2574 } else { 2575 // If this is a use, return the original decl. 2576 2577 // FIXME: In the future, return a variant or some other clue 2578 // for the consumer of this Decl to know it doesn't own it. 2579 // For our current ASTs this shouldn't be a problem, but will 2580 // need to be changed with DeclGroups. 2581 if (TK == TK_Reference) 2582 return PrevDecl; 2583 2584 // The new decl is a definition? 2585 if (TK == TK_Definition) { 2586 // Diagnose attempts to redefine a tag. 2587 if (RecordDecl* DefRecord = 2588 cast<RecordDecl>(PrevTagDecl)->getDefinition(Context)) { 2589 Diag(NameLoc, diag::err_redefinition) << Name; 2590 Diag(DefRecord->getLocation(), diag::note_previous_definition); 2591 // If this is a redefinition, recover by making this struct be 2592 // anonymous, which will make any later references get the previous 2593 // definition. 2594 Name = 0; 2595 PrevDecl = 0; 2596 } 2597 // Okay, this is definition of a previously declared or referenced 2598 // tag. We're going to create a new Decl. 2599 } 2600 } 2601 // If we get here we have (another) forward declaration. Just create 2602 // a new decl. 2603 } 2604 else { 2605 // If we get here, this is a definition of a new struct type in a nested 2606 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2607 // new decl/type. We set PrevDecl to NULL so that the Records 2608 // have distinct types. 2609 PrevDecl = 0; 2610 } 2611 } else { 2612 // PrevDecl is a namespace. 2613 if (isDeclInScope(PrevDecl, DC, S)) { 2614 // The tag name clashes with a namespace name, issue an error and 2615 // recover by making this tag be anonymous. 2616 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2617 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2618 Name = 0; 2619 } 2620 } 2621 } 2622 2623 CreateNewDecl: 2624 2625 // If there is an identifier, use the location of the identifier as the 2626 // location of the decl, otherwise use the location of the struct/union 2627 // keyword. 2628 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2629 2630 // Otherwise, if this is the first time we've seen this tag, create the decl. 2631 TagDecl *New; 2632 2633 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2634 // struct X { int A; } D; D should chain to X. 2635 if (getLangOptions().CPlusPlus) 2636 // FIXME: Look for a way to use RecordDecl for simple structs. 2637 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2638 dyn_cast_or_null<CXXRecordDecl>(PrevDecl)); 2639 else 2640 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2641 dyn_cast_or_null<RecordDecl>(PrevDecl)); 2642 2643 // If this has an identifier, add it to the scope stack. 2644 if ((TK == TK_Definition || !PrevDecl) && Name) { 2645 // The scope passed in may not be a decl scope. Zip up the scope tree until 2646 // we find one that is. 2647 while ((S->getFlags() & Scope::DeclScope) == 0) 2648 S = S->getParent(); 2649 2650 // Add it to the decl chain. 2651 PushOnScopeChains(New, S); 2652 } 2653 2654 // Handle #pragma pack: if the #pragma pack stack has non-default 2655 // alignment, make up a packed attribute for this decl. These 2656 // attributes are checked when the ASTContext lays out the 2657 // structure. 2658 // 2659 // It is important for implementing the correct semantics that this 2660 // happen here (in act on tag decl). The #pragma pack stack is 2661 // maintained as a result of parser callbacks which can occur at 2662 // many points during the parsing of a struct declaration (because 2663 // the #pragma tokens are effectively skipped over during the 2664 // parsing of the struct). 2665 if (unsigned Alignment = PackContext.getAlignment()) 2666 New->addAttr(new PackedAttr(Alignment * 8)); 2667 2668 if (Attr) 2669 ProcessDeclAttributeList(New, Attr); 2670 2671 // Set the lexical context. If the tag has a C++ scope specifier, the 2672 // lexical context will be different from the semantic context. 2673 New->setLexicalDeclContext(CurContext); 2674 2675 return New; 2676} 2677 2678 2679/// Collect the instance variables declared in an Objective-C object. Used in 2680/// the creation of structures from objects using the @defs directive. 2681static void CollectIvars(ObjCInterfaceDecl *Class, RecordDecl *Record, 2682 ASTContext& Ctx, 2683 llvm::SmallVectorImpl<Sema::DeclTy*> &ivars) { 2684 if (Class->getSuperClass()) 2685 CollectIvars(Class->getSuperClass(), Record, Ctx, ivars); 2686 2687 // For each ivar, create a fresh ObjCAtDefsFieldDecl. 2688 for (ObjCInterfaceDecl::ivar_iterator 2689 I=Class->ivar_begin(), E=Class->ivar_end(); I!=E; ++I) { 2690 2691 ObjCIvarDecl* ID = *I; 2692 ivars.push_back(ObjCAtDefsFieldDecl::Create(Ctx, Record, 2693 ID->getLocation(), 2694 ID->getIdentifier(), 2695 ID->getType(), 2696 ID->getBitWidth())); 2697 } 2698} 2699 2700/// Called whenever @defs(ClassName) is encountered in the source. Inserts the 2701/// instance variables of ClassName into Decls. 2702void Sema::ActOnDefs(Scope *S, DeclTy *TagD, SourceLocation DeclStart, 2703 IdentifierInfo *ClassName, 2704 llvm::SmallVectorImpl<DeclTy*> &Decls) { 2705 // Check that ClassName is a valid class 2706 ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName); 2707 if (!Class) { 2708 Diag(DeclStart, diag::err_undef_interface) << ClassName; 2709 return; 2710 } 2711 // Collect the instance variables 2712 CollectIvars(Class, dyn_cast<RecordDecl>((Decl*)TagD), Context, Decls); 2713 2714 // Introduce all of these fields into the appropriate scope. 2715 for (llvm::SmallVectorImpl<DeclTy*>::iterator D = Decls.begin(); 2716 D != Decls.end(); ++D) { 2717 FieldDecl *FD = cast<FieldDecl>((Decl*)*D); 2718 if (getLangOptions().CPlusPlus) 2719 PushOnScopeChains(cast<FieldDecl>(FD), S); 2720 else if (RecordDecl *Record = dyn_cast<RecordDecl>((Decl*)TagD)) 2721 Record->addDecl(Context, FD); 2722 } 2723} 2724 2725/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2726/// types into constant array types in certain situations which would otherwise 2727/// be errors (for GCC compatibility). 2728static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2729 ASTContext &Context) { 2730 // This method tries to turn a variable array into a constant 2731 // array even when the size isn't an ICE. This is necessary 2732 // for compatibility with code that depends on gcc's buggy 2733 // constant expression folding, like struct {char x[(int)(char*)2];} 2734 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2735 if (!VLATy) return QualType(); 2736 2737 APValue Result; 2738 if (!VLATy->getSizeExpr() || 2739 !VLATy->getSizeExpr()->Evaluate(Result, Context)) 2740 return QualType(); 2741 2742 assert(Result.isInt() && "Size expressions must be integers!"); 2743 llvm::APSInt &Res = Result.getInt(); 2744 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 2745 return Context.getConstantArrayType(VLATy->getElementType(), 2746 Res, ArrayType::Normal, 0); 2747 return QualType(); 2748} 2749 2750bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 2751 QualType FieldTy, const Expr *BitWidth) 2752{ 2753 // FIXME: 6.7.2.1p4 - verify the field type. 2754 2755 llvm::APSInt Value; 2756 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 2757 return true; 2758 2759 if (Value.isNegative()) { 2760 Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 2761 return true; 2762 } 2763 2764 uint64_t TypeSize = Context.getTypeSize(FieldTy); 2765 // FIXME: We won't need the 0 size once we check that the field type is valid. 2766 if (TypeSize && Value.getZExtValue() > TypeSize) { 2767 Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) << 2768 FieldName << (unsigned)TypeSize; 2769 return true; 2770 } 2771 2772 return false; 2773} 2774 2775/// ActOnField - Each field of a struct/union/class is passed into this in order 2776/// to create a FieldDecl object for it. 2777Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 2778 SourceLocation DeclStart, 2779 Declarator &D, ExprTy *BitfieldWidth) { 2780 IdentifierInfo *II = D.getIdentifier(); 2781 Expr *BitWidth = (Expr*)BitfieldWidth; 2782 SourceLocation Loc = DeclStart; 2783 RecordDecl *Record = (RecordDecl *)TagD; 2784 if (II) Loc = D.getIdentifierLoc(); 2785 2786 // FIXME: Unnamed fields can be handled in various different ways, for 2787 // example, unnamed unions inject all members into the struct namespace! 2788 2789 QualType T = GetTypeForDeclarator(D, S); 2790 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2791 bool InvalidDecl = false; 2792 2793 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2794 // than a variably modified type. 2795 if (T->isVariablyModifiedType()) { 2796 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 2797 if (!FixedTy.isNull()) { 2798 Diag(Loc, diag::warn_illegal_constant_array_size); 2799 T = FixedTy; 2800 } else { 2801 Diag(Loc, diag::err_typecheck_field_variable_size); 2802 T = Context.IntTy; 2803 InvalidDecl = true; 2804 } 2805 } 2806 2807 if (BitWidth) { 2808 if (VerifyBitField(Loc, II, T, BitWidth)) 2809 InvalidDecl = true; 2810 } else { 2811 // Not a bitfield. 2812 2813 // validate II. 2814 2815 } 2816 2817 // FIXME: Chain fielddecls together. 2818 FieldDecl *NewFD; 2819 2820 // FIXME: We don't want CurContext for C, do we? No, we'll need some 2821 // other way to determine the current RecordDecl. 2822 NewFD = FieldDecl::Create(Context, Record, 2823 Loc, II, T, BitWidth, 2824 D.getDeclSpec().getStorageClassSpec() == 2825 DeclSpec::SCS_mutable, 2826 /*PrevDecl=*/0); 2827 2828 ProcessDeclAttributes(NewFD, D); 2829 2830 if (D.getInvalidType() || InvalidDecl) 2831 NewFD->setInvalidDecl(); 2832 2833 if (II && getLangOptions().CPlusPlus) 2834 PushOnScopeChains(NewFD, S); 2835 else 2836 Record->addDecl(Context, NewFD); 2837 2838 return NewFD; 2839} 2840 2841/// TranslateIvarVisibility - Translate visibility from a token ID to an 2842/// AST enum value. 2843static ObjCIvarDecl::AccessControl 2844TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 2845 switch (ivarVisibility) { 2846 default: assert(0 && "Unknown visitibility kind"); 2847 case tok::objc_private: return ObjCIvarDecl::Private; 2848 case tok::objc_public: return ObjCIvarDecl::Public; 2849 case tok::objc_protected: return ObjCIvarDecl::Protected; 2850 case tok::objc_package: return ObjCIvarDecl::Package; 2851 } 2852} 2853 2854/// ActOnIvar - Each ivar field of an objective-c class is passed into this 2855/// in order to create an IvarDecl object for it. 2856Sema::DeclTy *Sema::ActOnIvar(Scope *S, 2857 SourceLocation DeclStart, 2858 Declarator &D, ExprTy *BitfieldWidth, 2859 tok::ObjCKeywordKind Visibility) { 2860 IdentifierInfo *II = D.getIdentifier(); 2861 Expr *BitWidth = (Expr*)BitfieldWidth; 2862 SourceLocation Loc = DeclStart; 2863 if (II) Loc = D.getIdentifierLoc(); 2864 2865 // FIXME: Unnamed fields can be handled in various different ways, for 2866 // example, unnamed unions inject all members into the struct namespace! 2867 2868 QualType T = GetTypeForDeclarator(D, S); 2869 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2870 bool InvalidDecl = false; 2871 2872 if (BitWidth) { 2873 // TODO: Validate. 2874 //printf("WARNING: BITFIELDS IGNORED!\n"); 2875 2876 // 6.7.2.1p3 2877 // 6.7.2.1p4 2878 2879 } else { 2880 // Not a bitfield. 2881 2882 // validate II. 2883 2884 } 2885 2886 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2887 // than a variably modified type. 2888 if (T->isVariablyModifiedType()) { 2889 Diag(Loc, diag::err_typecheck_ivar_variable_size); 2890 InvalidDecl = true; 2891 } 2892 2893 // Get the visibility (access control) for this ivar. 2894 ObjCIvarDecl::AccessControl ac = 2895 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 2896 : ObjCIvarDecl::None; 2897 2898 // Construct the decl. 2899 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 2900 (Expr *)BitfieldWidth); 2901 2902 // Process attributes attached to the ivar. 2903 ProcessDeclAttributes(NewID, D); 2904 2905 if (D.getInvalidType() || InvalidDecl) 2906 NewID->setInvalidDecl(); 2907 2908 return NewID; 2909} 2910 2911void Sema::ActOnFields(Scope* S, 2912 SourceLocation RecLoc, DeclTy *RecDecl, 2913 DeclTy **Fields, unsigned NumFields, 2914 SourceLocation LBrac, SourceLocation RBrac, 2915 AttributeList *Attr) { 2916 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 2917 assert(EnclosingDecl && "missing record or interface decl"); 2918 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 2919 2920 if (Record) 2921 if (RecordDecl* DefRecord = Record->getDefinition(Context)) { 2922 // Diagnose code like: 2923 // struct S { struct S {} X; }; 2924 // We discover this when we complete the outer S. Reject and ignore the 2925 // outer S. 2926 Diag(DefRecord->getLocation(), diag::err_nested_redefinition) 2927 << DefRecord->getDeclName(); 2928 Diag(RecLoc, diag::note_previous_definition); 2929 Record->setInvalidDecl(); 2930 return; 2931 } 2932 2933 // Verify that all the fields are okay. 2934 unsigned NumNamedMembers = 0; 2935 llvm::SmallVector<FieldDecl*, 32> RecFields; 2936 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 2937 2938 for (unsigned i = 0; i != NumFields; ++i) { 2939 2940 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 2941 assert(FD && "missing field decl"); 2942 2943 // Remember all fields. 2944 RecFields.push_back(FD); 2945 2946 // Get the type for the field. 2947 Type *FDTy = FD->getType().getTypePtr(); 2948 2949 // C99 6.7.2.1p2 - A field may not be a function type. 2950 if (FDTy->isFunctionType()) { 2951 Diag(FD->getLocation(), diag::err_field_declared_as_function) 2952 << FD->getDeclName(); 2953 FD->setInvalidDecl(); 2954 EnclosingDecl->setInvalidDecl(); 2955 continue; 2956 } 2957 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 2958 if (FDTy->isIncompleteType()) { 2959 if (!Record) { // Incomplete ivar type is always an error. 2960 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 2961 FD->setInvalidDecl(); 2962 EnclosingDecl->setInvalidDecl(); 2963 continue; 2964 } 2965 if (i != NumFields-1 || // ... that the last member ... 2966 !Record->isStruct() || // ... of a structure ... 2967 !FDTy->isArrayType()) { //... may have incomplete array type. 2968 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 2969 FD->setInvalidDecl(); 2970 EnclosingDecl->setInvalidDecl(); 2971 continue; 2972 } 2973 if (NumNamedMembers < 1) { //... must have more than named member ... 2974 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 2975 << FD->getDeclName(); 2976 FD->setInvalidDecl(); 2977 EnclosingDecl->setInvalidDecl(); 2978 continue; 2979 } 2980 // Okay, we have a legal flexible array member at the end of the struct. 2981 if (Record) 2982 Record->setHasFlexibleArrayMember(true); 2983 } 2984 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 2985 /// field of another structure or the element of an array. 2986 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 2987 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 2988 // If this is a member of a union, then entire union becomes "flexible". 2989 if (Record && Record->isUnion()) { 2990 Record->setHasFlexibleArrayMember(true); 2991 } else { 2992 // If this is a struct/class and this is not the last element, reject 2993 // it. Note that GCC supports variable sized arrays in the middle of 2994 // structures. 2995 if (i != NumFields-1) { 2996 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 2997 << FD->getDeclName(); 2998 FD->setInvalidDecl(); 2999 EnclosingDecl->setInvalidDecl(); 3000 continue; 3001 } 3002 // We support flexible arrays at the end of structs in other structs 3003 // as an extension. 3004 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3005 << FD->getDeclName(); 3006 if (Record) 3007 Record->setHasFlexibleArrayMember(true); 3008 } 3009 } 3010 } 3011 /// A field cannot be an Objective-c object 3012 if (FDTy->isObjCInterfaceType()) { 3013 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3014 << FD->getDeclName(); 3015 FD->setInvalidDecl(); 3016 EnclosingDecl->setInvalidDecl(); 3017 continue; 3018 } 3019 // Keep track of the number of named members. 3020 if (IdentifierInfo *II = FD->getIdentifier()) { 3021 // Detect duplicate member names. 3022 if (!FieldIDs.insert(II)) { 3023 Diag(FD->getLocation(), diag::err_duplicate_member) << II; 3024 // Find the previous decl. 3025 SourceLocation PrevLoc; 3026 for (unsigned i = 0; ; ++i) { 3027 assert(i != RecFields.size() && "Didn't find previous def!"); 3028 if (RecFields[i]->getIdentifier() == II) { 3029 PrevLoc = RecFields[i]->getLocation(); 3030 break; 3031 } 3032 } 3033 Diag(PrevLoc, diag::note_previous_definition); 3034 FD->setInvalidDecl(); 3035 EnclosingDecl->setInvalidDecl(); 3036 continue; 3037 } 3038 ++NumNamedMembers; 3039 } 3040 } 3041 3042 // Okay, we successfully defined 'Record'. 3043 if (Record) { 3044 Record->completeDefinition(Context); 3045 // If this is a C++ record, HandleTagDeclDefinition will be invoked in 3046 // Sema::ActOnFinishCXXClassDef. 3047 if (!isa<CXXRecordDecl>(Record)) 3048 Consumer.HandleTagDeclDefinition(Record); 3049 } else { 3050 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3051 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 3052 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3053 else if (ObjCImplementationDecl *IMPDecl = 3054 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3055 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3056 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3057 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3058 } 3059 } 3060 3061 if (Attr) 3062 ProcessDeclAttributeList(Record, Attr); 3063} 3064 3065Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3066 DeclTy *lastEnumConst, 3067 SourceLocation IdLoc, IdentifierInfo *Id, 3068 SourceLocation EqualLoc, ExprTy *val) { 3069 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3070 EnumConstantDecl *LastEnumConst = 3071 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3072 Expr *Val = static_cast<Expr*>(val); 3073 3074 // The scope passed in may not be a decl scope. Zip up the scope tree until 3075 // we find one that is. 3076 while ((S->getFlags() & Scope::DeclScope) == 0) 3077 S = S->getParent(); 3078 3079 // Verify that there isn't already something declared with this name in this 3080 // scope. 3081 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3082 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3083 // Maybe we will complain about the shadowed template parameter. 3084 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3085 // Just pretend that we didn't see the previous declaration. 3086 PrevDecl = 0; 3087 } 3088 3089 if (PrevDecl) { 3090 // When in C++, we may get a TagDecl with the same name; in this case the 3091 // enum constant will 'hide' the tag. 3092 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3093 "Received TagDecl when not in C++!"); 3094 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3095 if (isa<EnumConstantDecl>(PrevDecl)) 3096 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3097 else 3098 Diag(IdLoc, diag::err_redefinition) << Id; 3099 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3100 delete Val; 3101 return 0; 3102 } 3103 } 3104 3105 llvm::APSInt EnumVal(32); 3106 QualType EltTy; 3107 if (Val) { 3108 // Make sure to promote the operand type to int. 3109 UsualUnaryConversions(Val); 3110 3111 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3112 SourceLocation ExpLoc; 3113 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3114 delete Val; 3115 Val = 0; // Just forget about it. 3116 } else { 3117 EltTy = Val->getType(); 3118 } 3119 } 3120 3121 if (!Val) { 3122 if (LastEnumConst) { 3123 // Assign the last value + 1. 3124 EnumVal = LastEnumConst->getInitVal(); 3125 ++EnumVal; 3126 3127 // Check for overflow on increment. 3128 if (EnumVal < LastEnumConst->getInitVal()) 3129 Diag(IdLoc, diag::warn_enum_value_overflow); 3130 3131 EltTy = LastEnumConst->getType(); 3132 } else { 3133 // First value, set to zero. 3134 EltTy = Context.IntTy; 3135 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3136 } 3137 } 3138 3139 EnumConstantDecl *New = 3140 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3141 Val, EnumVal, 3142 LastEnumConst); 3143 3144 // Register this decl in the current scope stack. 3145 PushOnScopeChains(New, S); 3146 return New; 3147} 3148 3149// FIXME: For consistency with ActOnFields(), we should have the parser 3150// pass in the source location for the left/right braces. 3151void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3152 DeclTy **Elements, unsigned NumElements) { 3153 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3154 3155 if (Enum && Enum->isDefinition()) { 3156 // Diagnose code like: 3157 // enum e0 { 3158 // E0 = sizeof(enum e0 { E1 }) 3159 // }; 3160 Diag(Enum->getLocation(), diag::err_nested_redefinition) 3161 << Enum->getDeclName(); 3162 Diag(EnumLoc, diag::note_previous_definition); 3163 Enum->setInvalidDecl(); 3164 return; 3165 } 3166 // TODO: If the result value doesn't fit in an int, it must be a long or long 3167 // long value. ISO C does not support this, but GCC does as an extension, 3168 // emit a warning. 3169 unsigned IntWidth = Context.Target.getIntWidth(); 3170 3171 // Verify that all the values are okay, compute the size of the values, and 3172 // reverse the list. 3173 unsigned NumNegativeBits = 0; 3174 unsigned NumPositiveBits = 0; 3175 3176 // Keep track of whether all elements have type int. 3177 bool AllElementsInt = true; 3178 3179 EnumConstantDecl *EltList = 0; 3180 for (unsigned i = 0; i != NumElements; ++i) { 3181 EnumConstantDecl *ECD = 3182 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3183 if (!ECD) continue; // Already issued a diagnostic. 3184 3185 // If the enum value doesn't fit in an int, emit an extension warning. 3186 const llvm::APSInt &InitVal = ECD->getInitVal(); 3187 assert(InitVal.getBitWidth() >= IntWidth && 3188 "Should have promoted value to int"); 3189 if (InitVal.getBitWidth() > IntWidth) { 3190 llvm::APSInt V(InitVal); 3191 V.trunc(IntWidth); 3192 V.extend(InitVal.getBitWidth()); 3193 if (V != InitVal) 3194 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3195 << InitVal.toString(10); 3196 } 3197 3198 // Keep track of the size of positive and negative values. 3199 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3200 NumPositiveBits = std::max(NumPositiveBits, 3201 (unsigned)InitVal.getActiveBits()); 3202 else 3203 NumNegativeBits = std::max(NumNegativeBits, 3204 (unsigned)InitVal.getMinSignedBits()); 3205 3206 // Keep track of whether every enum element has type int (very commmon). 3207 if (AllElementsInt) 3208 AllElementsInt = ECD->getType() == Context.IntTy; 3209 3210 ECD->setNextDeclarator(EltList); 3211 EltList = ECD; 3212 } 3213 3214 // Figure out the type that should be used for this enum. 3215 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3216 QualType BestType; 3217 unsigned BestWidth; 3218 3219 if (NumNegativeBits) { 3220 // If there is a negative value, figure out the smallest integer type (of 3221 // int/long/longlong) that fits. 3222 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3223 BestType = Context.IntTy; 3224 BestWidth = IntWidth; 3225 } else { 3226 BestWidth = Context.Target.getLongWidth(); 3227 3228 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3229 BestType = Context.LongTy; 3230 else { 3231 BestWidth = Context.Target.getLongLongWidth(); 3232 3233 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3234 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3235 BestType = Context.LongLongTy; 3236 } 3237 } 3238 } else { 3239 // If there is no negative value, figure out which of uint, ulong, ulonglong 3240 // fits. 3241 if (NumPositiveBits <= IntWidth) { 3242 BestType = Context.UnsignedIntTy; 3243 BestWidth = IntWidth; 3244 } else if (NumPositiveBits <= 3245 (BestWidth = Context.Target.getLongWidth())) { 3246 BestType = Context.UnsignedLongTy; 3247 } else { 3248 BestWidth = Context.Target.getLongLongWidth(); 3249 assert(NumPositiveBits <= BestWidth && 3250 "How could an initializer get larger than ULL?"); 3251 BestType = Context.UnsignedLongLongTy; 3252 } 3253 } 3254 3255 // Loop over all of the enumerator constants, changing their types to match 3256 // the type of the enum if needed. 3257 for (unsigned i = 0; i != NumElements; ++i) { 3258 EnumConstantDecl *ECD = 3259 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3260 if (!ECD) continue; // Already issued a diagnostic. 3261 3262 // Standard C says the enumerators have int type, but we allow, as an 3263 // extension, the enumerators to be larger than int size. If each 3264 // enumerator value fits in an int, type it as an int, otherwise type it the 3265 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3266 // that X has type 'int', not 'unsigned'. 3267 if (ECD->getType() == Context.IntTy) { 3268 // Make sure the init value is signed. 3269 llvm::APSInt IV = ECD->getInitVal(); 3270 IV.setIsSigned(true); 3271 ECD->setInitVal(IV); 3272 continue; // Already int type. 3273 } 3274 3275 // Determine whether the value fits into an int. 3276 llvm::APSInt InitVal = ECD->getInitVal(); 3277 bool FitsInInt; 3278 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3279 FitsInInt = InitVal.getActiveBits() < IntWidth; 3280 else 3281 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3282 3283 // If it fits into an integer type, force it. Otherwise force it to match 3284 // the enum decl type. 3285 QualType NewTy; 3286 unsigned NewWidth; 3287 bool NewSign; 3288 if (FitsInInt) { 3289 NewTy = Context.IntTy; 3290 NewWidth = IntWidth; 3291 NewSign = true; 3292 } else if (ECD->getType() == BestType) { 3293 // Already the right type! 3294 continue; 3295 } else { 3296 NewTy = BestType; 3297 NewWidth = BestWidth; 3298 NewSign = BestType->isSignedIntegerType(); 3299 } 3300 3301 // Adjust the APSInt value. 3302 InitVal.extOrTrunc(NewWidth); 3303 InitVal.setIsSigned(NewSign); 3304 ECD->setInitVal(InitVal); 3305 3306 // Adjust the Expr initializer and type. 3307 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3308 /*isLvalue=*/false)); 3309 ECD->setType(NewTy); 3310 } 3311 3312 Enum->completeDefinition(Context, BestType); 3313 Consumer.HandleTagDeclDefinition(Enum); 3314} 3315 3316Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3317 ExprTy *expr) { 3318 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 3319 3320 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3321} 3322 3323Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 3324 SourceLocation LBrace, 3325 SourceLocation RBrace, 3326 const char *Lang, 3327 unsigned StrSize, 3328 DeclTy *D) { 3329 LinkageSpecDecl::LanguageIDs Language; 3330 Decl *dcl = static_cast<Decl *>(D); 3331 if (strncmp(Lang, "\"C\"", StrSize) == 0) 3332 Language = LinkageSpecDecl::lang_c; 3333 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 3334 Language = LinkageSpecDecl::lang_cxx; 3335 else { 3336 Diag(Loc, diag::err_bad_language); 3337 return 0; 3338 } 3339 3340 // FIXME: Add all the various semantics of linkage specifications 3341 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 3342} 3343 3344void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3345 ExprTy *alignment, SourceLocation PragmaLoc, 3346 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3347 Expr *Alignment = static_cast<Expr *>(alignment); 3348 3349 // If specified then alignment must be a "small" power of two. 3350 unsigned AlignmentVal = 0; 3351 if (Alignment) { 3352 llvm::APSInt Val; 3353 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3354 !Val.isPowerOf2() || 3355 Val.getZExtValue() > 16) { 3356 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3357 delete Alignment; 3358 return; // Ignore 3359 } 3360 3361 AlignmentVal = (unsigned) Val.getZExtValue(); 3362 } 3363 3364 switch (Kind) { 3365 case Action::PPK_Default: // pack([n]) 3366 PackContext.setAlignment(AlignmentVal); 3367 break; 3368 3369 case Action::PPK_Show: // pack(show) 3370 // Show the current alignment, making sure to show the right value 3371 // for the default. 3372 AlignmentVal = PackContext.getAlignment(); 3373 // FIXME: This should come from the target. 3374 if (AlignmentVal == 0) 3375 AlignmentVal = 8; 3376 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3377 break; 3378 3379 case Action::PPK_Push: // pack(push [, id] [, [n]) 3380 PackContext.push(Name); 3381 // Set the new alignment if specified. 3382 if (Alignment) 3383 PackContext.setAlignment(AlignmentVal); 3384 break; 3385 3386 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3387 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3388 // "#pragma pack(pop, identifier, n) is undefined" 3389 if (Alignment && Name) 3390 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3391 3392 // Do the pop. 3393 if (!PackContext.pop(Name)) { 3394 // If a name was specified then failure indicates the name 3395 // wasn't found. Otherwise failure indicates the stack was 3396 // empty. 3397 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3398 << (Name ? "no record matching name" : "stack empty"); 3399 3400 // FIXME: Warn about popping named records as MSVC does. 3401 } else { 3402 // Pop succeeded, set the new alignment if specified. 3403 if (Alignment) 3404 PackContext.setAlignment(AlignmentVal); 3405 } 3406 break; 3407 3408 default: 3409 assert(0 && "Invalid #pragma pack kind."); 3410 } 3411} 3412 3413bool PragmaPackStack::pop(IdentifierInfo *Name) { 3414 if (Stack.empty()) 3415 return false; 3416 3417 // If name is empty just pop top. 3418 if (!Name) { 3419 Alignment = Stack.back().first; 3420 Stack.pop_back(); 3421 return true; 3422 } 3423 3424 // Otherwise, find the named record. 3425 for (unsigned i = Stack.size(); i != 0; ) { 3426 --i; 3427 if (Stack[i].second == Name) { 3428 // Found it, pop up to and including this record. 3429 Alignment = Stack[i].first; 3430 Stack.erase(Stack.begin() + i, Stack.end()); 3431 return true; 3432 } 3433 } 3434 3435 return false; 3436} 3437