SemaDecl.cpp revision f780abc21c39cd4731b9e38f2d2d9f7d1510bd7b
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31 32using namespace clang; 33 34Sema::TypeTy *Sema::isTypeName(IdentifierInfo &II, Scope *S, 35 const CXXScopeSpec *SS) { 36 DeclContext *DC = 0; 37 if (SS) { 38 if (SS->isInvalid()) 39 return 0; 40 DC = static_cast<DeclContext*>(SS->getScopeRep()); 41 } 42 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC, false); 43 44 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 45 isa<ObjCInterfaceDecl>(IIDecl) || 46 isa<TagDecl>(IIDecl) || 47 isa<TemplateTypeParmDecl>(IIDecl))) 48 return IIDecl; 49 return 0; 50} 51 52DeclContext *Sema::getContainingDC(DeclContext *DC) { 53 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 54 // A C++ out-of-line method will return to the file declaration context. 55 if (MD->isOutOfLineDefinition()) 56 return MD->getLexicalDeclContext(); 57 58 // A C++ inline method is parsed *after* the topmost class it was declared in 59 // is fully parsed (it's "complete"). 60 // The parsing of a C++ inline method happens at the declaration context of 61 // the topmost (non-nested) class it is lexically declared in. 62 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 63 DC = MD->getParent(); 64 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 65 DC = RD; 66 67 // Return the declaration context of the topmost class the inline method is 68 // declared in. 69 return DC; 70 } 71 72 if (isa<ObjCMethodDecl>(DC)) 73 return Context.getTranslationUnitDecl(); 74 75 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(DC)) 76 return SD->getLexicalDeclContext(); 77 78 return DC->getLexicalParent(); 79} 80 81void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 82 assert(getContainingDC(DC) == CurContext && 83 "The next DeclContext should be lexically contained in the current one."); 84 CurContext = DC; 85 S->setEntity(DC); 86} 87 88void Sema::PopDeclContext() { 89 assert(CurContext && "DeclContext imbalance!"); 90 91 CurContext = getContainingDC(CurContext); 92} 93 94/// Add this decl to the scope shadowed decl chains. 95void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 96 S->AddDecl(D); 97 98 // Add scoped declarations into their context, so that they can be 99 // found later. Declarations without a context won't be inserted 100 // into any context. 101 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D)) 102 CurContext->addDecl(Context, SD); 103 104 // C++ [basic.scope]p4: 105 // -- exactly one declaration shall declare a class name or 106 // enumeration name that is not a typedef name and the other 107 // declarations shall all refer to the same object or 108 // enumerator, or all refer to functions and function templates; 109 // in this case the class name or enumeration name is hidden. 110 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 111 // We are pushing the name of a tag (enum or class). 112 if (CurContext == TD->getDeclContext()) { 113 // We're pushing the tag into the current context, which might 114 // require some reshuffling in the identifier resolver. 115 IdentifierResolver::iterator 116 I = IdResolver.begin(TD->getDeclName(), CurContext, 117 false/*LookInParentCtx*/), 118 IEnd = IdResolver.end(); 119 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 120 NamedDecl *PrevDecl = *I; 121 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 122 PrevDecl = *I, ++I) { 123 if (TD->declarationReplaces(*I)) { 124 // This is a redeclaration. Remove it from the chain and 125 // break out, so that we'll add in the shadowed 126 // declaration. 127 S->RemoveDecl(*I); 128 if (PrevDecl == *I) { 129 IdResolver.RemoveDecl(*I); 130 IdResolver.AddDecl(TD); 131 return; 132 } else { 133 IdResolver.RemoveDecl(*I); 134 break; 135 } 136 } 137 } 138 139 // There is already a declaration with the same name in the same 140 // scope, which is not a tag declaration. It must be found 141 // before we find the new declaration, so insert the new 142 // declaration at the end of the chain. 143 IdResolver.AddShadowedDecl(TD, PrevDecl); 144 145 return; 146 } 147 } 148 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 149 // We are pushing the name of a function, which might be an 150 // overloaded name. 151 FunctionDecl *FD = cast<FunctionDecl>(D); 152 IdentifierResolver::iterator Redecl 153 = std::find_if(IdResolver.begin(FD->getDeclName(), CurContext, 154 false/*LookInParentCtx*/), 155 IdResolver.end(), 156 std::bind1st(std::mem_fun(&ScopedDecl::declarationReplaces), 157 FD)); 158 if (Redecl != IdResolver.end()) { 159 // There is already a declaration of a function on our 160 // IdResolver chain. Replace it with this declaration. 161 S->RemoveDecl(*Redecl); 162 IdResolver.RemoveDecl(*Redecl); 163 } 164 } 165 166 IdResolver.AddDecl(D); 167} 168 169void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 170 if (S->decl_empty()) return; 171 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 172 "Scope shouldn't contain decls!"); 173 174 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 175 I != E; ++I) { 176 Decl *TmpD = static_cast<Decl*>(*I); 177 assert(TmpD && "This decl didn't get pushed??"); 178 179 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 180 NamedDecl *D = cast<NamedDecl>(TmpD); 181 182 if (!D->getDeclName()) continue; 183 184 // Remove this name from our lexical scope. 185 IdResolver.RemoveDecl(D); 186 } 187} 188 189/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 190/// return 0 if one not found. 191ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 192 // The third "scope" argument is 0 since we aren't enabling lazy built-in 193 // creation from this context. 194 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 195 196 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 197} 198 199/// MaybeConstructOverloadSet - Name lookup has determined that the 200/// elements in [I, IEnd) have the name that we are looking for, and 201/// *I is a match for the namespace. This routine returns an 202/// appropriate Decl for name lookup, which may either be *I or an 203/// OverloadeFunctionDecl that represents the overloaded functions in 204/// [I, IEnd). 205/// 206/// The existance of this routine is temporary; LookupDecl should 207/// probably be able to return multiple results, to deal with cases of 208/// ambiguity and overloaded functions without needing to create a 209/// Decl node. 210template<typename DeclIterator> 211static Decl * 212MaybeConstructOverloadSet(ASTContext &Context, 213 DeclIterator I, DeclIterator IEnd) { 214 assert(I != IEnd && "Iterator range cannot be empty"); 215 assert(!isa<OverloadedFunctionDecl>(*I) && 216 "Cannot have an overloaded function"); 217 218 if (isa<FunctionDecl>(*I)) { 219 // If we found a function, there might be more functions. If 220 // so, collect them into an overload set. 221 DeclIterator Last = I; 222 OverloadedFunctionDecl *Ovl = 0; 223 for (++Last; Last != IEnd && isa<FunctionDecl>(*Last); ++Last) { 224 if (!Ovl) { 225 // FIXME: We leak this overload set. Eventually, we want to 226 // stop building the declarations for these overload sets, so 227 // there will be nothing to leak. 228 Ovl = OverloadedFunctionDecl::Create(Context, 229 cast<ScopedDecl>(*I)->getDeclContext(), 230 (*I)->getDeclName()); 231 Ovl->addOverload(cast<FunctionDecl>(*I)); 232 } 233 Ovl->addOverload(cast<FunctionDecl>(*Last)); 234 } 235 236 // If we had more than one function, we built an overload 237 // set. Return it. 238 if (Ovl) 239 return Ovl; 240 } 241 242 return *I; 243} 244 245/// LookupDecl - Look up the inner-most declaration in the specified 246/// namespace. NamespaceNameOnly - during lookup only namespace names 247/// are considered as required in C++ [basic.lookup.udir] 3.4.6.p1 248/// 'When looking up a namespace-name in a using-directive or 249/// namespace-alias-definition, only namespace names are considered.' 250Decl *Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 251 const DeclContext *LookupCtx, 252 bool enableLazyBuiltinCreation, 253 bool LookInParent, 254 bool NamespaceNameOnly) { 255 if (!Name) return 0; 256 unsigned NS = NSI; 257 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 258 NS |= Decl::IDNS_Tag; 259 260 if (LookupCtx == 0 && 261 (!getLangOptions().CPlusPlus || (NS == Decl::IDNS_Label))) { 262 // Unqualified name lookup in C/Objective-C and name lookup for 263 // labels in C++ is purely lexical, so search in the 264 // declarations attached to the name. 265 assert(!LookupCtx && "Can't perform qualified name lookup here"); 266 assert(!NamespaceNameOnly && "Can't perform namespace name lookup here"); 267 IdentifierResolver::iterator I 268 = IdResolver.begin(Name, CurContext, LookInParent); 269 270 // Scan up the scope chain looking for a decl that matches this 271 // identifier that is in the appropriate namespace. This search 272 // should not take long, as shadowing of names is uncommon, and 273 // deep shadowing is extremely uncommon. 274 for (; I != IdResolver.end(); ++I) 275 if ((*I)->getIdentifierNamespace() & NS) 276 return *I; 277 } else if (LookupCtx) { 278 // Perform qualified name lookup into the LookupCtx. 279 // FIXME: Will need to look into base classes and such. 280 DeclContext::lookup_const_iterator I, E; 281 for (llvm::tie(I, E) = LookupCtx->lookup(Context, Name); I != E; ++I) 282 if ((*I)->getIdentifierNamespace() & NS) { 283 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) { 284 // Skip non-namespace name. 285 } else { 286 return MaybeConstructOverloadSet(Context, I, E); 287 } 288 } 289 } else { 290 // Name lookup for ordinary names and tag names in C++ requires 291 // looking into scopes that aren't strictly lexical, and 292 // therefore we walk through the context as well as walking 293 // through the scopes. 294 IdentifierResolver::iterator 295 I = IdResolver.begin(Name, CurContext, true/*LookInParentCtx*/), 296 IEnd = IdResolver.end(); 297 for (; S; S = S->getParent()) { 298 // Check whether the IdResolver has anything in this scope. 299 // FIXME: The isDeclScope check could be expensive. Can we do better? 300 for (; I != IEnd && S->isDeclScope(*I); ++I) { 301 if ((*I)->getIdentifierNamespace() & NS) { 302 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) { 303 // Skip non-namespace name. 304 } else { 305 // We found something. Look for anything else in our scope 306 // with this same name and in an acceptable identifier 307 // namespace, so that we can construct an overload set if we 308 // need to. 309 IdentifierResolver::iterator LastI = I; 310 for (++LastI; LastI != IEnd; ++LastI) { 311 if (((*LastI)->getIdentifierNamespace() & NS) == 0 || 312 !S->isDeclScope(*LastI)) 313 break; 314 } 315 return MaybeConstructOverloadSet(Context, I, LastI); 316 } 317 } 318 } 319 320 // If there is an entity associated with this scope, it's a 321 // DeclContext. We might need to perform qualified lookup into 322 // it. 323 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 324 while (Ctx && Ctx->isFunctionOrMethod()) 325 Ctx = Ctx->getParent(); 326 while (Ctx && (Ctx->isNamespace() || Ctx->isCXXRecord())) { 327 // Look for declarations of this name in this scope. 328 DeclContext::lookup_const_iterator I, E; 329 for (llvm::tie(I, E) = Ctx->lookup(Context, Name); I != E; ++I) { 330 // FIXME: Cache this result in the IdResolver 331 if ((*I)->getIdentifierNamespace() & NS) { 332 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) {} 333 else return MaybeConstructOverloadSet(Context, I, E); 334 } 335 } 336 337 Ctx = Ctx->getParent(); 338 } 339 340 if (!LookInParent) 341 return 0; 342 } 343 } 344 345 // If we didn't find a use of this identifier, and if the identifier 346 // corresponds to a compiler builtin, create the decl object for the builtin 347 // now, injecting it into translation unit scope, and return it. 348 if (NS & Decl::IDNS_Ordinary) { 349 IdentifierInfo *II = Name.getAsIdentifierInfo(); 350 if (enableLazyBuiltinCreation && II && 351 (LookupCtx == 0 || isa<TranslationUnitDecl>(LookupCtx))) { 352 // If this is a builtin on this (or all) targets, create the decl. 353 if (unsigned BuiltinID = II->getBuiltinID()) 354 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 355 } 356 if (getLangOptions().ObjC1 && II) { 357 // @interface and @compatibility_alias introduce typedef-like names. 358 // Unlike typedef's, they can only be introduced at file-scope (and are 359 // therefore not scoped decls). They can, however, be shadowed by 360 // other names in IDNS_Ordinary. 361 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 362 if (IDI != ObjCInterfaceDecls.end()) 363 return IDI->second; 364 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 365 if (I != ObjCAliasDecls.end()) 366 return I->second->getClassInterface(); 367 } 368 } 369 return 0; 370} 371 372void Sema::InitBuiltinVaListType() { 373 if (!Context.getBuiltinVaListType().isNull()) 374 return; 375 376 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 377 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 378 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 379 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 380} 381 382/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 383/// lazily create a decl for it. 384ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 385 Scope *S) { 386 Builtin::ID BID = (Builtin::ID)bid; 387 388 if (Context.BuiltinInfo.hasVAListUse(BID)) 389 InitBuiltinVaListType(); 390 391 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 392 FunctionDecl *New = FunctionDecl::Create(Context, 393 Context.getTranslationUnitDecl(), 394 SourceLocation(), II, R, 395 FunctionDecl::Extern, false, 0); 396 397 // Create Decl objects for each parameter, adding them to the 398 // FunctionDecl. 399 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 400 llvm::SmallVector<ParmVarDecl*, 16> Params; 401 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 402 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 403 FT->getArgType(i), VarDecl::None, 0, 404 0)); 405 New->setParams(&Params[0], Params.size()); 406 } 407 408 409 410 // TUScope is the translation-unit scope to insert this function into. 411 PushOnScopeChains(New, TUScope); 412 return New; 413} 414 415/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 416/// everything from the standard library is defined. 417NamespaceDecl *Sema::GetStdNamespace() { 418 if (!StdNamespace) { 419 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 420 DeclContext *Global = Context.getTranslationUnitDecl(); 421 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Tag | Decl::IDNS_Ordinary, 422 0, Global, /*enableLazyBuiltinCreation=*/false); 423 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 424 } 425 return StdNamespace; 426} 427 428/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 429/// and scope as a previous declaration 'Old'. Figure out how to resolve this 430/// situation, merging decls or emitting diagnostics as appropriate. 431/// 432TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 433 // Allow multiple definitions for ObjC built-in typedefs. 434 // FIXME: Verify the underlying types are equivalent! 435 if (getLangOptions().ObjC1) { 436 const IdentifierInfo *TypeID = New->getIdentifier(); 437 switch (TypeID->getLength()) { 438 default: break; 439 case 2: 440 if (!TypeID->isStr("id")) 441 break; 442 Context.setObjCIdType(New); 443 return New; 444 case 5: 445 if (!TypeID->isStr("Class")) 446 break; 447 Context.setObjCClassType(New); 448 return New; 449 case 3: 450 if (!TypeID->isStr("SEL")) 451 break; 452 Context.setObjCSelType(New); 453 return New; 454 case 8: 455 if (!TypeID->isStr("Protocol")) 456 break; 457 Context.setObjCProtoType(New->getUnderlyingType()); 458 return New; 459 } 460 // Fall through - the typedef name was not a builtin type. 461 } 462 // Verify the old decl was also a typedef. 463 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 464 if (!Old) { 465 Diag(New->getLocation(), diag::err_redefinition_different_kind) 466 << New->getDeclName(); 467 Diag(OldD->getLocation(), diag::note_previous_definition); 468 return New; 469 } 470 471 // If the typedef types are not identical, reject them in all languages and 472 // with any extensions enabled. 473 if (Old->getUnderlyingType() != New->getUnderlyingType() && 474 Context.getCanonicalType(Old->getUnderlyingType()) != 475 Context.getCanonicalType(New->getUnderlyingType())) { 476 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 477 << New->getUnderlyingType() << Old->getUnderlyingType(); 478 Diag(Old->getLocation(), diag::note_previous_definition); 479 return Old; 480 } 481 482 if (getLangOptions().Microsoft) return New; 483 484 // C++ [dcl.typedef]p2: 485 // In a given non-class scope, a typedef specifier can be used to 486 // redefine the name of any type declared in that scope to refer 487 // to the type to which it already refers. 488 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 489 return New; 490 491 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 492 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 493 // *either* declaration is in a system header. The code below implements 494 // this adhoc compatibility rule. FIXME: The following code will not 495 // work properly when compiling ".i" files (containing preprocessed output). 496 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 497 SourceManager &SrcMgr = Context.getSourceManager(); 498 if (SrcMgr.isInSystemHeader(Old->getLocation())) 499 return New; 500 if (SrcMgr.isInSystemHeader(New->getLocation())) 501 return New; 502 } 503 504 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 505 Diag(Old->getLocation(), diag::note_previous_definition); 506 return New; 507} 508 509/// DeclhasAttr - returns true if decl Declaration already has the target 510/// attribute. 511static bool DeclHasAttr(const Decl *decl, const Attr *target) { 512 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 513 if (attr->getKind() == target->getKind()) 514 return true; 515 516 return false; 517} 518 519/// MergeAttributes - append attributes from the Old decl to the New one. 520static void MergeAttributes(Decl *New, Decl *Old) { 521 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 522 523 while (attr) { 524 tmp = attr; 525 attr = attr->getNext(); 526 527 if (!DeclHasAttr(New, tmp)) { 528 tmp->setInherited(true); 529 New->addAttr(tmp); 530 } else { 531 tmp->setNext(0); 532 delete(tmp); 533 } 534 } 535 536 Old->invalidateAttrs(); 537} 538 539/// MergeFunctionDecl - We just parsed a function 'New' from 540/// declarator D which has the same name and scope as a previous 541/// declaration 'Old'. Figure out how to resolve this situation, 542/// merging decls or emitting diagnostics as appropriate. 543/// Redeclaration will be set true if this New is a redeclaration OldD. 544/// 545/// In C++, New and Old must be declarations that are not 546/// overloaded. Use IsOverload to determine whether New and Old are 547/// overloaded, and to select the Old declaration that New should be 548/// merged with. 549FunctionDecl * 550Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 551 assert(!isa<OverloadedFunctionDecl>(OldD) && 552 "Cannot merge with an overloaded function declaration"); 553 554 Redeclaration = false; 555 // Verify the old decl was also a function. 556 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 557 if (!Old) { 558 Diag(New->getLocation(), diag::err_redefinition_different_kind) 559 << New->getDeclName(); 560 Diag(OldD->getLocation(), diag::note_previous_definition); 561 return New; 562 } 563 564 // Determine whether the previous declaration was a definition, 565 // implicit declaration, or a declaration. 566 diag::kind PrevDiag; 567 if (Old->isThisDeclarationADefinition()) 568 PrevDiag = diag::note_previous_definition; 569 else if (Old->isImplicit()) 570 PrevDiag = diag::note_previous_implicit_declaration; 571 else 572 PrevDiag = diag::note_previous_declaration; 573 574 QualType OldQType = Context.getCanonicalType(Old->getType()); 575 QualType NewQType = Context.getCanonicalType(New->getType()); 576 577 if (getLangOptions().CPlusPlus) { 578 // (C++98 13.1p2): 579 // Certain function declarations cannot be overloaded: 580 // -- Function declarations that differ only in the return type 581 // cannot be overloaded. 582 QualType OldReturnType 583 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 584 QualType NewReturnType 585 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 586 if (OldReturnType != NewReturnType) { 587 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 588 Diag(Old->getLocation(), PrevDiag); 589 Redeclaration = true; 590 return New; 591 } 592 593 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 594 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 595 if (OldMethod && NewMethod) { 596 // -- Member function declarations with the same name and the 597 // same parameter types cannot be overloaded if any of them 598 // is a static member function declaration. 599 if (OldMethod->isStatic() || NewMethod->isStatic()) { 600 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 601 Diag(Old->getLocation(), PrevDiag); 602 return New; 603 } 604 605 // C++ [class.mem]p1: 606 // [...] A member shall not be declared twice in the 607 // member-specification, except that a nested class or member 608 // class template can be declared and then later defined. 609 if (OldMethod->getLexicalDeclContext() == 610 NewMethod->getLexicalDeclContext()) { 611 unsigned NewDiag; 612 if (isa<CXXConstructorDecl>(OldMethod)) 613 NewDiag = diag::err_constructor_redeclared; 614 else if (isa<CXXDestructorDecl>(NewMethod)) 615 NewDiag = diag::err_destructor_redeclared; 616 else if (isa<CXXConversionDecl>(NewMethod)) 617 NewDiag = diag::err_conv_function_redeclared; 618 else 619 NewDiag = diag::err_member_redeclared; 620 621 Diag(New->getLocation(), NewDiag); 622 Diag(Old->getLocation(), PrevDiag); 623 } 624 } 625 626 // (C++98 8.3.5p3): 627 // All declarations for a function shall agree exactly in both the 628 // return type and the parameter-type-list. 629 if (OldQType == NewQType) { 630 // We have a redeclaration. 631 MergeAttributes(New, Old); 632 Redeclaration = true; 633 return MergeCXXFunctionDecl(New, Old); 634 } 635 636 // Fall through for conflicting redeclarations and redefinitions. 637 } 638 639 // C: Function types need to be compatible, not identical. This handles 640 // duplicate function decls like "void f(int); void f(enum X);" properly. 641 if (!getLangOptions().CPlusPlus && 642 Context.typesAreCompatible(OldQType, NewQType)) { 643 MergeAttributes(New, Old); 644 Redeclaration = true; 645 return New; 646 } 647 648 // A function that has already been declared has been redeclared or defined 649 // with a different type- show appropriate diagnostic 650 651 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 652 // TODO: This is totally simplistic. It should handle merging functions 653 // together etc, merging extern int X; int X; ... 654 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 655 Diag(Old->getLocation(), PrevDiag); 656 return New; 657} 658 659/// Predicate for C "tentative" external object definitions (C99 6.9.2). 660static bool isTentativeDefinition(VarDecl *VD) { 661 if (VD->isFileVarDecl()) 662 return (!VD->getInit() && 663 (VD->getStorageClass() == VarDecl::None || 664 VD->getStorageClass() == VarDecl::Static)); 665 return false; 666} 667 668/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 669/// when dealing with C "tentative" external object definitions (C99 6.9.2). 670void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 671 bool VDIsTentative = isTentativeDefinition(VD); 672 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 673 674 // FIXME: I don't this will actually see all of the 675 // redefinitions. Can't we check this property on-the-fly? 676 for (IdentifierResolver::iterator 677 I = IdResolver.begin(VD->getIdentifier(), 678 VD->getDeclContext(), false/*LookInParentCtx*/), 679 E = IdResolver.end(); I != E; ++I) { 680 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 681 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 682 683 // Handle the following case: 684 // int a[10]; 685 // int a[]; - the code below makes sure we set the correct type. 686 // int a[11]; - this is an error, size isn't 10. 687 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 688 OldDecl->getType()->isConstantArrayType()) 689 VD->setType(OldDecl->getType()); 690 691 // Check for "tentative" definitions. We can't accomplish this in 692 // MergeVarDecl since the initializer hasn't been attached. 693 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 694 continue; 695 696 // Handle __private_extern__ just like extern. 697 if (OldDecl->getStorageClass() != VarDecl::Extern && 698 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 699 VD->getStorageClass() != VarDecl::Extern && 700 VD->getStorageClass() != VarDecl::PrivateExtern) { 701 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 702 Diag(OldDecl->getLocation(), diag::note_previous_definition); 703 } 704 } 705 } 706} 707 708/// MergeVarDecl - We just parsed a variable 'New' which has the same name 709/// and scope as a previous declaration 'Old'. Figure out how to resolve this 710/// situation, merging decls or emitting diagnostics as appropriate. 711/// 712/// Tentative definition rules (C99 6.9.2p2) are checked by 713/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 714/// definitions here, since the initializer hasn't been attached. 715/// 716VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 717 // Verify the old decl was also a variable. 718 VarDecl *Old = dyn_cast<VarDecl>(OldD); 719 if (!Old) { 720 Diag(New->getLocation(), diag::err_redefinition_different_kind) 721 << New->getDeclName(); 722 Diag(OldD->getLocation(), diag::note_previous_definition); 723 return New; 724 } 725 726 MergeAttributes(New, Old); 727 728 // Verify the types match. 729 QualType OldCType = Context.getCanonicalType(Old->getType()); 730 QualType NewCType = Context.getCanonicalType(New->getType()); 731 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 732 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 733 Diag(Old->getLocation(), diag::note_previous_definition); 734 return New; 735 } 736 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 737 if (New->getStorageClass() == VarDecl::Static && 738 (Old->getStorageClass() == VarDecl::None || 739 Old->getStorageClass() == VarDecl::Extern)) { 740 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 741 Diag(Old->getLocation(), diag::note_previous_definition); 742 return New; 743 } 744 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 745 if (New->getStorageClass() != VarDecl::Static && 746 Old->getStorageClass() == VarDecl::Static) { 747 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 748 Diag(Old->getLocation(), diag::note_previous_definition); 749 return New; 750 } 751 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 752 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 753 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 754 Diag(Old->getLocation(), diag::note_previous_definition); 755 } 756 return New; 757} 758 759/// CheckParmsForFunctionDef - Check that the parameters of the given 760/// function are appropriate for the definition of a function. This 761/// takes care of any checks that cannot be performed on the 762/// declaration itself, e.g., that the types of each of the function 763/// parameters are complete. 764bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 765 bool HasInvalidParm = false; 766 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 767 ParmVarDecl *Param = FD->getParamDecl(p); 768 769 // C99 6.7.5.3p4: the parameters in a parameter type list in a 770 // function declarator that is part of a function definition of 771 // that function shall not have incomplete type. 772 if (Param->getType()->isIncompleteType() && 773 !Param->isInvalidDecl()) { 774 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 775 << Param->getType(); 776 Param->setInvalidDecl(); 777 HasInvalidParm = true; 778 } 779 780 // C99 6.9.1p5: If the declarator includes a parameter type list, the 781 // declaration of each parameter shall include an identifier. 782 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 783 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 784 } 785 786 return HasInvalidParm; 787} 788 789/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 790/// no declarator (e.g. "struct foo;") is parsed. 791Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 792 // FIXME: Isn't that more of a parser diagnostic than a sema diagnostic? 793 if (!DS.isMissingDeclaratorOk()) { 794 // FIXME: This diagnostic is emitted even when various previous 795 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 796 // DeclSpec has no means of communicating this information, and the 797 // responsible parser functions are quite far apart. 798 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 799 << DS.getSourceRange(); 800 return 0; 801 } 802 803 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 804} 805 806bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 807 // Get the type before calling CheckSingleAssignmentConstraints(), since 808 // it can promote the expression. 809 QualType InitType = Init->getType(); 810 811 if (getLangOptions().CPlusPlus) 812 return PerformCopyInitialization(Init, DeclType, "initializing"); 813 814 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 815 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 816 InitType, Init, "initializing"); 817} 818 819bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 820 const ArrayType *AT = Context.getAsArrayType(DeclT); 821 822 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 823 // C99 6.7.8p14. We have an array of character type with unknown size 824 // being initialized to a string literal. 825 llvm::APSInt ConstVal(32); 826 ConstVal = strLiteral->getByteLength() + 1; 827 // Return a new array type (C99 6.7.8p22). 828 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 829 ArrayType::Normal, 0); 830 } else { 831 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 832 // C99 6.7.8p14. We have an array of character type with known size. 833 // FIXME: Avoid truncation for 64-bit length strings. 834 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 835 Diag(strLiteral->getSourceRange().getBegin(), 836 diag::warn_initializer_string_for_char_array_too_long) 837 << strLiteral->getSourceRange(); 838 } 839 // Set type from "char *" to "constant array of char". 840 strLiteral->setType(DeclT); 841 // For now, we always return false (meaning success). 842 return false; 843} 844 845StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 846 const ArrayType *AT = Context.getAsArrayType(DeclType); 847 if (AT && AT->getElementType()->isCharType()) { 848 return dyn_cast<StringLiteral>(Init); 849 } 850 return 0; 851} 852 853bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 854 SourceLocation InitLoc, 855 DeclarationName InitEntity) { 856 if (DeclType->isDependentType() || Init->isTypeDependent()) 857 return false; 858 859 // C++ [dcl.init.ref]p1: 860 // A variable declared to be a T&, that is "reference to type T" 861 // (8.3.2), shall be initialized by an object, or function, of 862 // type T or by an object that can be converted into a T. 863 if (DeclType->isReferenceType()) 864 return CheckReferenceInit(Init, DeclType); 865 866 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 867 // of unknown size ("[]") or an object type that is not a variable array type. 868 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 869 return Diag(InitLoc, diag::err_variable_object_no_init) 870 << VAT->getSizeExpr()->getSourceRange(); 871 872 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 873 if (!InitList) { 874 // FIXME: Handle wide strings 875 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 876 return CheckStringLiteralInit(strLiteral, DeclType); 877 878 // C++ [dcl.init]p14: 879 // -- If the destination type is a (possibly cv-qualified) class 880 // type: 881 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 882 QualType DeclTypeC = Context.getCanonicalType(DeclType); 883 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 884 885 // -- If the initialization is direct-initialization, or if it is 886 // copy-initialization where the cv-unqualified version of the 887 // source type is the same class as, or a derived class of, the 888 // class of the destination, constructors are considered. 889 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 890 IsDerivedFrom(InitTypeC, DeclTypeC)) { 891 CXXConstructorDecl *Constructor 892 = PerformInitializationByConstructor(DeclType, &Init, 1, 893 InitLoc, Init->getSourceRange(), 894 InitEntity, IK_Copy); 895 return Constructor == 0; 896 } 897 898 // -- Otherwise (i.e., for the remaining copy-initialization 899 // cases), user-defined conversion sequences that can 900 // convert from the source type to the destination type or 901 // (when a conversion function is used) to a derived class 902 // thereof are enumerated as described in 13.3.1.4, and the 903 // best one is chosen through overload resolution 904 // (13.3). If the conversion cannot be done or is 905 // ambiguous, the initialization is ill-formed. The 906 // function selected is called with the initializer 907 // expression as its argument; if the function is a 908 // constructor, the call initializes a temporary of the 909 // destination type. 910 // FIXME: We're pretending to do copy elision here; return to 911 // this when we have ASTs for such things. 912 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 913 return false; 914 915 if (InitEntity) 916 return Diag(InitLoc, diag::err_cannot_initialize_decl) 917 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 918 << Init->getType() << Init->getSourceRange(); 919 else 920 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 921 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 922 << Init->getType() << Init->getSourceRange(); 923 } 924 925 // C99 6.7.8p16. 926 if (DeclType->isArrayType()) 927 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 928 << Init->getSourceRange(); 929 930 return CheckSingleInitializer(Init, DeclType); 931 } else if (getLangOptions().CPlusPlus) { 932 // C++ [dcl.init]p14: 933 // [...] If the class is an aggregate (8.5.1), and the initializer 934 // is a brace-enclosed list, see 8.5.1. 935 // 936 // Note: 8.5.1 is handled below; here, we diagnose the case where 937 // we have an initializer list and a destination type that is not 938 // an aggregate. 939 // FIXME: In C++0x, this is yet another form of initialization. 940 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 941 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 942 if (!ClassDecl->isAggregate()) 943 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 944 << DeclType << Init->getSourceRange(); 945 } 946 } 947 948 InitListChecker CheckInitList(this, InitList, DeclType); 949 return CheckInitList.HadError(); 950} 951 952/// GetNameForDeclarator - Determine the full declaration name for the 953/// given Declarator. 954DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 955 switch (D.getKind()) { 956 case Declarator::DK_Abstract: 957 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 958 return DeclarationName(); 959 960 case Declarator::DK_Normal: 961 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 962 return DeclarationName(D.getIdentifier()); 963 964 case Declarator::DK_Constructor: { 965 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 966 Ty = Context.getCanonicalType(Ty); 967 return Context.DeclarationNames.getCXXConstructorName(Ty); 968 } 969 970 case Declarator::DK_Destructor: { 971 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 972 Ty = Context.getCanonicalType(Ty); 973 return Context.DeclarationNames.getCXXDestructorName(Ty); 974 } 975 976 case Declarator::DK_Conversion: { 977 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 978 Ty = Context.getCanonicalType(Ty); 979 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 980 } 981 982 case Declarator::DK_Operator: 983 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 984 return Context.DeclarationNames.getCXXOperatorName( 985 D.getOverloadedOperator()); 986 } 987 988 assert(false && "Unknown name kind"); 989 return DeclarationName(); 990} 991 992/// isNearlyMatchingMemberFunction - Determine whether the C++ member 993/// functions Declaration and Definition are "nearly" matching. This 994/// heuristic is used to improve diagnostics in the case where an 995/// out-of-line member function definition doesn't match any 996/// declaration within the class. 997static bool isNearlyMatchingMemberFunction(ASTContext &Context, 998 FunctionDecl *Declaration, 999 FunctionDecl *Definition) { 1000 if (Declaration->param_size() != Definition->param_size()) 1001 return false; 1002 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1003 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1004 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1005 1006 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1007 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1008 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1009 return false; 1010 } 1011 1012 return true; 1013} 1014 1015Sema::DeclTy * 1016Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1017 bool IsFunctionDefinition) { 1018 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 1019 DeclarationName Name = GetNameForDeclarator(D); 1020 1021 // All of these full declarators require an identifier. If it doesn't have 1022 // one, the ParsedFreeStandingDeclSpec action should be used. 1023 if (!Name) { 1024 if (!D.getInvalidType()) // Reject this if we think it is valid. 1025 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1026 diag::err_declarator_need_ident) 1027 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1028 return 0; 1029 } 1030 1031 // The scope passed in may not be a decl scope. Zip up the scope tree until 1032 // we find one that is. 1033 while ((S->getFlags() & Scope::DeclScope) == 0 || 1034 (S->getFlags() & Scope::TemplateParamScope) != 0) 1035 S = S->getParent(); 1036 1037 DeclContext *DC; 1038 Decl *PrevDecl; 1039 ScopedDecl *New; 1040 bool InvalidDecl = false; 1041 1042 // See if this is a redefinition of a variable in the same scope. 1043 if (!D.getCXXScopeSpec().isSet()) { 1044 DC = CurContext; 1045 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1046 } else { // Something like "int foo::x;" 1047 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1048 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1049 1050 // C++ 7.3.1.2p2: 1051 // Members (including explicit specializations of templates) of a named 1052 // namespace can also be defined outside that namespace by explicit 1053 // qualification of the name being defined, provided that the entity being 1054 // defined was already declared in the namespace and the definition appears 1055 // after the point of declaration in a namespace that encloses the 1056 // declarations namespace. 1057 // 1058 // Note that we only check the context at this point. We don't yet 1059 // have enough information to make sure that PrevDecl is actually 1060 // the declaration we want to match. For example, given: 1061 // 1062 // class X { 1063 // void f(); 1064 // void f(float); 1065 // }; 1066 // 1067 // void X::f(int) { } // ill-formed 1068 // 1069 // In this case, PrevDecl will point to the overload set 1070 // containing the two f's declared in X, but neither of them 1071 // matches. 1072 if (!CurContext->Encloses(DC)) { 1073 // The qualifying scope doesn't enclose the original declaration. 1074 // Emit diagnostic based on current scope. 1075 SourceLocation L = D.getIdentifierLoc(); 1076 SourceRange R = D.getCXXScopeSpec().getRange(); 1077 if (isa<FunctionDecl>(CurContext)) { 1078 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1079 } else { 1080 Diag(L, diag::err_invalid_declarator_scope) 1081 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1082 } 1083 InvalidDecl = true; 1084 } 1085 } 1086 1087 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1088 // Maybe we will complain about the shadowed template parameter. 1089 InvalidDecl = InvalidDecl 1090 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1091 // Just pretend that we didn't see the previous declaration. 1092 PrevDecl = 0; 1093 } 1094 1095 // In C++, the previous declaration we find might be a tag type 1096 // (class or enum). In this case, the new declaration will hide the 1097 // tag type. 1098 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1099 PrevDecl = 0; 1100 1101 QualType R = GetTypeForDeclarator(D, S); 1102 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1103 1104 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1105 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1106 if (D.getCXXScopeSpec().isSet()) { 1107 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1108 << D.getCXXScopeSpec().getRange(); 1109 InvalidDecl = true; 1110 // Pretend we didn't see the scope specifier. 1111 DC = 0; 1112 } 1113 1114 // Check that there are no default arguments (C++ only). 1115 if (getLangOptions().CPlusPlus) 1116 CheckExtraCXXDefaultArguments(D); 1117 1118 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1119 if (!NewTD) return 0; 1120 1121 // Handle attributes prior to checking for duplicates in MergeVarDecl 1122 ProcessDeclAttributes(NewTD, D); 1123 // Merge the decl with the existing one if appropriate. If the decl is 1124 // in an outer scope, it isn't the same thing. 1125 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1126 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1127 if (NewTD == 0) return 0; 1128 } 1129 New = NewTD; 1130 if (S->getFnParent() == 0) { 1131 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1132 // then it shall have block scope. 1133 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1134 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1135 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1136 else 1137 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1138 1139 InvalidDecl = true; 1140 } 1141 } 1142 } else if (R.getTypePtr()->isFunctionType()) { 1143 FunctionDecl::StorageClass SC = FunctionDecl::None; 1144 switch (D.getDeclSpec().getStorageClassSpec()) { 1145 default: assert(0 && "Unknown storage class!"); 1146 case DeclSpec::SCS_auto: 1147 case DeclSpec::SCS_register: 1148 case DeclSpec::SCS_mutable: 1149 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1150 InvalidDecl = true; 1151 break; 1152 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1153 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1154 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1155 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1156 } 1157 1158 bool isInline = D.getDeclSpec().isInlineSpecified(); 1159 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1160 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1161 1162 FunctionDecl *NewFD; 1163 if (D.getKind() == Declarator::DK_Constructor) { 1164 // This is a C++ constructor declaration. 1165 assert(DC->isCXXRecord() && 1166 "Constructors can only be declared in a member context"); 1167 1168 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1169 1170 // Create the new declaration 1171 NewFD = CXXConstructorDecl::Create(Context, 1172 cast<CXXRecordDecl>(DC), 1173 D.getIdentifierLoc(), Name, R, 1174 isExplicit, isInline, 1175 /*isImplicitlyDeclared=*/false); 1176 1177 if (InvalidDecl) 1178 NewFD->setInvalidDecl(); 1179 } else if (D.getKind() == Declarator::DK_Destructor) { 1180 // This is a C++ destructor declaration. 1181 if (DC->isCXXRecord()) { 1182 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1183 1184 NewFD = CXXDestructorDecl::Create(Context, 1185 cast<CXXRecordDecl>(DC), 1186 D.getIdentifierLoc(), Name, R, 1187 isInline, 1188 /*isImplicitlyDeclared=*/false); 1189 1190 if (InvalidDecl) 1191 NewFD->setInvalidDecl(); 1192 } else { 1193 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1194 1195 // Create a FunctionDecl to satisfy the function definition parsing 1196 // code path. 1197 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1198 Name, R, SC, isInline, LastDeclarator, 1199 // FIXME: Move to DeclGroup... 1200 D.getDeclSpec().getSourceRange().getBegin()); 1201 InvalidDecl = true; 1202 NewFD->setInvalidDecl(); 1203 } 1204 } else if (D.getKind() == Declarator::DK_Conversion) { 1205 if (!DC->isCXXRecord()) { 1206 Diag(D.getIdentifierLoc(), 1207 diag::err_conv_function_not_member); 1208 return 0; 1209 } else { 1210 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1211 1212 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1213 D.getIdentifierLoc(), Name, R, 1214 isInline, isExplicit); 1215 1216 if (InvalidDecl) 1217 NewFD->setInvalidDecl(); 1218 } 1219 } else if (DC->isCXXRecord()) { 1220 // This is a C++ method declaration. 1221 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1222 D.getIdentifierLoc(), Name, R, 1223 (SC == FunctionDecl::Static), isInline, 1224 LastDeclarator); 1225 } else { 1226 NewFD = FunctionDecl::Create(Context, DC, 1227 D.getIdentifierLoc(), 1228 Name, R, SC, isInline, LastDeclarator, 1229 // FIXME: Move to DeclGroup... 1230 D.getDeclSpec().getSourceRange().getBegin()); 1231 } 1232 1233 // Set the lexical context. If the declarator has a C++ 1234 // scope specifier, the lexical context will be different 1235 // from the semantic context. 1236 NewFD->setLexicalDeclContext(CurContext); 1237 1238 // Handle GNU asm-label extension (encoded as an attribute). 1239 if (Expr *E = (Expr*) D.getAsmLabel()) { 1240 // The parser guarantees this is a string. 1241 StringLiteral *SE = cast<StringLiteral>(E); 1242 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1243 SE->getByteLength()))); 1244 } 1245 1246 // Copy the parameter declarations from the declarator D to 1247 // the function declaration NewFD, if they are available. 1248 if (D.getNumTypeObjects() > 0) { 1249 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1250 1251 // Create Decl objects for each parameter, adding them to the 1252 // FunctionDecl. 1253 llvm::SmallVector<ParmVarDecl*, 16> Params; 1254 1255 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1256 // function that takes no arguments, not a function that takes a 1257 // single void argument. 1258 // We let through "const void" here because Sema::GetTypeForDeclarator 1259 // already checks for that case. 1260 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1261 FTI.ArgInfo[0].Param && 1262 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1263 // empty arg list, don't push any params. 1264 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1265 1266 // In C++, the empty parameter-type-list must be spelled "void"; a 1267 // typedef of void is not permitted. 1268 if (getLangOptions().CPlusPlus && 1269 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1270 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1271 } 1272 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1273 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1274 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1275 } 1276 1277 NewFD->setParams(&Params[0], Params.size()); 1278 } else if (R->getAsTypedefType()) { 1279 // When we're declaring a function with a typedef, as in the 1280 // following example, we'll need to synthesize (unnamed) 1281 // parameters for use in the declaration. 1282 // 1283 // @code 1284 // typedef void fn(int); 1285 // fn f; 1286 // @endcode 1287 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1288 if (!FT) { 1289 // This is a typedef of a function with no prototype, so we 1290 // don't need to do anything. 1291 } else if ((FT->getNumArgs() == 0) || 1292 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1293 FT->getArgType(0)->isVoidType())) { 1294 // This is a zero-argument function. We don't need to do anything. 1295 } else { 1296 // Synthesize a parameter for each argument type. 1297 llvm::SmallVector<ParmVarDecl*, 16> Params; 1298 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1299 ArgType != FT->arg_type_end(); ++ArgType) { 1300 Params.push_back(ParmVarDecl::Create(Context, DC, 1301 SourceLocation(), 0, 1302 *ArgType, VarDecl::None, 1303 0, 0)); 1304 } 1305 1306 NewFD->setParams(&Params[0], Params.size()); 1307 } 1308 } 1309 1310 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1311 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1312 else if (isa<CXXDestructorDecl>(NewFD)) 1313 cast<CXXRecordDecl>(NewFD->getParent())->setUserDeclaredDestructor(true); 1314 else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(NewFD)) 1315 ActOnConversionDeclarator(Conversion); 1316 1317 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1318 if (NewFD->isOverloadedOperator() && 1319 CheckOverloadedOperatorDeclaration(NewFD)) 1320 NewFD->setInvalidDecl(); 1321 1322 // Merge the decl with the existing one if appropriate. Since C functions 1323 // are in a flat namespace, make sure we consider decls in outer scopes. 1324 if (PrevDecl && 1325 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1326 bool Redeclaration = false; 1327 1328 // If C++, determine whether NewFD is an overload of PrevDecl or 1329 // a declaration that requires merging. If it's an overload, 1330 // there's no more work to do here; we'll just add the new 1331 // function to the scope. 1332 OverloadedFunctionDecl::function_iterator MatchedDecl; 1333 if (!getLangOptions().CPlusPlus || 1334 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1335 Decl *OldDecl = PrevDecl; 1336 1337 // If PrevDecl was an overloaded function, extract the 1338 // FunctionDecl that matched. 1339 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1340 OldDecl = *MatchedDecl; 1341 1342 // NewFD and PrevDecl represent declarations that need to be 1343 // merged. 1344 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1345 1346 if (NewFD == 0) return 0; 1347 if (Redeclaration) { 1348 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1349 1350 // An out-of-line member function declaration must also be a 1351 // definition (C++ [dcl.meaning]p1). 1352 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1353 !InvalidDecl) { 1354 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1355 << D.getCXXScopeSpec().getRange(); 1356 NewFD->setInvalidDecl(); 1357 } 1358 } 1359 } 1360 1361 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1362 // The user tried to provide an out-of-line definition for a 1363 // member function, but there was no such member function 1364 // declared (C++ [class.mfct]p2). For example: 1365 // 1366 // class X { 1367 // void f() const; 1368 // }; 1369 // 1370 // void X::f() { } // ill-formed 1371 // 1372 // Complain about this problem, and attempt to suggest close 1373 // matches (e.g., those that differ only in cv-qualifiers and 1374 // whether the parameter types are references). 1375 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1376 << cast<CXXRecordDecl>(DC)->getDeclName() 1377 << D.getCXXScopeSpec().getRange(); 1378 InvalidDecl = true; 1379 1380 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1381 if (!PrevDecl) { 1382 // Nothing to suggest. 1383 } else if (OverloadedFunctionDecl *Ovl 1384 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1385 for (OverloadedFunctionDecl::function_iterator 1386 Func = Ovl->function_begin(), 1387 FuncEnd = Ovl->function_end(); 1388 Func != FuncEnd; ++Func) { 1389 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1390 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1391 1392 } 1393 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1394 // Suggest this no matter how mismatched it is; it's the only 1395 // thing we have. 1396 unsigned diag; 1397 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1398 diag = diag::note_member_def_close_match; 1399 else if (Method->getBody()) 1400 diag = diag::note_previous_definition; 1401 else 1402 diag = diag::note_previous_declaration; 1403 Diag(Method->getLocation(), diag); 1404 } 1405 1406 PrevDecl = 0; 1407 } 1408 } 1409 // Handle attributes. We need to have merged decls when handling attributes 1410 // (for example to check for conflicts, etc). 1411 ProcessDeclAttributes(NewFD, D); 1412 New = NewFD; 1413 1414 if (getLangOptions().CPlusPlus) { 1415 // In C++, check default arguments now that we have merged decls. 1416 CheckCXXDefaultArguments(NewFD); 1417 1418 // An out-of-line member function declaration must also be a 1419 // definition (C++ [dcl.meaning]p1). 1420 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1421 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1422 << D.getCXXScopeSpec().getRange(); 1423 InvalidDecl = true; 1424 } 1425 } 1426 } else { 1427 // Check that there are no default arguments (C++ only). 1428 if (getLangOptions().CPlusPlus) 1429 CheckExtraCXXDefaultArguments(D); 1430 1431 if (R.getTypePtr()->isObjCInterfaceType()) { 1432 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1433 << D.getIdentifier(); 1434 InvalidDecl = true; 1435 } 1436 1437 VarDecl *NewVD; 1438 VarDecl::StorageClass SC; 1439 switch (D.getDeclSpec().getStorageClassSpec()) { 1440 default: assert(0 && "Unknown storage class!"); 1441 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1442 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1443 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1444 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1445 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1446 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1447 case DeclSpec::SCS_mutable: 1448 // mutable can only appear on non-static class members, so it's always 1449 // an error here 1450 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1451 InvalidDecl = true; 1452 SC = VarDecl::None; 1453 break; 1454 } 1455 1456 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1457 if (!II) { 1458 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1459 << Name.getAsString(); 1460 return 0; 1461 } 1462 1463 if (DC->isCXXRecord()) { 1464 // This is a static data member for a C++ class. 1465 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1466 D.getIdentifierLoc(), II, 1467 R, LastDeclarator); 1468 } else { 1469 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1470 if (S->getFnParent() == 0) { 1471 // C99 6.9p2: The storage-class specifiers auto and register shall not 1472 // appear in the declaration specifiers in an external declaration. 1473 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1474 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1475 InvalidDecl = true; 1476 } 1477 } 1478 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1479 II, R, SC, LastDeclarator, 1480 // FIXME: Move to DeclGroup... 1481 D.getDeclSpec().getSourceRange().getBegin()); 1482 NewVD->setThreadSpecified(ThreadSpecified); 1483 } 1484 // Handle attributes prior to checking for duplicates in MergeVarDecl 1485 ProcessDeclAttributes(NewVD, D); 1486 1487 // Handle GNU asm-label extension (encoded as an attribute). 1488 if (Expr *E = (Expr*) D.getAsmLabel()) { 1489 // The parser guarantees this is a string. 1490 StringLiteral *SE = cast<StringLiteral>(E); 1491 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1492 SE->getByteLength()))); 1493 } 1494 1495 // Emit an error if an address space was applied to decl with local storage. 1496 // This includes arrays of objects with address space qualifiers, but not 1497 // automatic variables that point to other address spaces. 1498 // ISO/IEC TR 18037 S5.1.2 1499 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1500 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1501 InvalidDecl = true; 1502 } 1503 // Merge the decl with the existing one if appropriate. If the decl is 1504 // in an outer scope, it isn't the same thing. 1505 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1506 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1507 // The user tried to define a non-static data member 1508 // out-of-line (C++ [dcl.meaning]p1). 1509 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1510 << D.getCXXScopeSpec().getRange(); 1511 NewVD->Destroy(Context); 1512 return 0; 1513 } 1514 1515 NewVD = MergeVarDecl(NewVD, PrevDecl); 1516 if (NewVD == 0) return 0; 1517 1518 if (D.getCXXScopeSpec().isSet()) { 1519 // No previous declaration in the qualifying scope. 1520 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1521 << Name << D.getCXXScopeSpec().getRange(); 1522 InvalidDecl = true; 1523 } 1524 } 1525 New = NewVD; 1526 } 1527 1528 // Set the lexical context. If the declarator has a C++ scope specifier, the 1529 // lexical context will be different from the semantic context. 1530 New->setLexicalDeclContext(CurContext); 1531 1532 // If this has an identifier, add it to the scope stack. 1533 if (Name) 1534 PushOnScopeChains(New, S); 1535 // If any semantic error occurred, mark the decl as invalid. 1536 if (D.getInvalidType() || InvalidDecl) 1537 New->setInvalidDecl(); 1538 1539 return New; 1540} 1541 1542void Sema::InitializerElementNotConstant(const Expr *Init) { 1543 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1544 << Init->getSourceRange(); 1545} 1546 1547bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1548 switch (Init->getStmtClass()) { 1549 default: 1550 InitializerElementNotConstant(Init); 1551 return true; 1552 case Expr::ParenExprClass: { 1553 const ParenExpr* PE = cast<ParenExpr>(Init); 1554 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1555 } 1556 case Expr::CompoundLiteralExprClass: 1557 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1558 case Expr::DeclRefExprClass: { 1559 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1560 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1561 if (VD->hasGlobalStorage()) 1562 return false; 1563 InitializerElementNotConstant(Init); 1564 return true; 1565 } 1566 if (isa<FunctionDecl>(D)) 1567 return false; 1568 InitializerElementNotConstant(Init); 1569 return true; 1570 } 1571 case Expr::MemberExprClass: { 1572 const MemberExpr *M = cast<MemberExpr>(Init); 1573 if (M->isArrow()) 1574 return CheckAddressConstantExpression(M->getBase()); 1575 return CheckAddressConstantExpressionLValue(M->getBase()); 1576 } 1577 case Expr::ArraySubscriptExprClass: { 1578 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1579 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1580 return CheckAddressConstantExpression(ASE->getBase()) || 1581 CheckArithmeticConstantExpression(ASE->getIdx()); 1582 } 1583 case Expr::StringLiteralClass: 1584 case Expr::PredefinedExprClass: 1585 return false; 1586 case Expr::UnaryOperatorClass: { 1587 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1588 1589 // C99 6.6p9 1590 if (Exp->getOpcode() == UnaryOperator::Deref) 1591 return CheckAddressConstantExpression(Exp->getSubExpr()); 1592 1593 InitializerElementNotConstant(Init); 1594 return true; 1595 } 1596 } 1597} 1598 1599bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1600 switch (Init->getStmtClass()) { 1601 default: 1602 InitializerElementNotConstant(Init); 1603 return true; 1604 case Expr::ParenExprClass: 1605 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1606 case Expr::StringLiteralClass: 1607 case Expr::ObjCStringLiteralClass: 1608 return false; 1609 case Expr::CallExprClass: 1610 case Expr::CXXOperatorCallExprClass: 1611 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1612 if (cast<CallExpr>(Init)->isBuiltinCall() == 1613 Builtin::BI__builtin___CFStringMakeConstantString) 1614 return false; 1615 1616 InitializerElementNotConstant(Init); 1617 return true; 1618 1619 case Expr::UnaryOperatorClass: { 1620 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1621 1622 // C99 6.6p9 1623 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1624 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1625 1626 if (Exp->getOpcode() == UnaryOperator::Extension) 1627 return CheckAddressConstantExpression(Exp->getSubExpr()); 1628 1629 InitializerElementNotConstant(Init); 1630 return true; 1631 } 1632 case Expr::BinaryOperatorClass: { 1633 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1634 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1635 1636 Expr *PExp = Exp->getLHS(); 1637 Expr *IExp = Exp->getRHS(); 1638 if (IExp->getType()->isPointerType()) 1639 std::swap(PExp, IExp); 1640 1641 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1642 return CheckAddressConstantExpression(PExp) || 1643 CheckArithmeticConstantExpression(IExp); 1644 } 1645 case Expr::ImplicitCastExprClass: 1646 case Expr::CStyleCastExprClass: { 1647 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1648 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1649 // Check for implicit promotion 1650 if (SubExpr->getType()->isFunctionType() || 1651 SubExpr->getType()->isArrayType()) 1652 return CheckAddressConstantExpressionLValue(SubExpr); 1653 } 1654 1655 // Check for pointer->pointer cast 1656 if (SubExpr->getType()->isPointerType()) 1657 return CheckAddressConstantExpression(SubExpr); 1658 1659 if (SubExpr->getType()->isIntegralType()) { 1660 // Check for the special-case of a pointer->int->pointer cast; 1661 // this isn't standard, but some code requires it. See 1662 // PR2720 for an example. 1663 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1664 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1665 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1666 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1667 if (IntWidth >= PointerWidth) { 1668 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1669 } 1670 } 1671 } 1672 } 1673 if (SubExpr->getType()->isArithmeticType()) { 1674 return CheckArithmeticConstantExpression(SubExpr); 1675 } 1676 1677 InitializerElementNotConstant(Init); 1678 return true; 1679 } 1680 case Expr::ConditionalOperatorClass: { 1681 // FIXME: Should we pedwarn here? 1682 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1683 if (!Exp->getCond()->getType()->isArithmeticType()) { 1684 InitializerElementNotConstant(Init); 1685 return true; 1686 } 1687 if (CheckArithmeticConstantExpression(Exp->getCond())) 1688 return true; 1689 if (Exp->getLHS() && 1690 CheckAddressConstantExpression(Exp->getLHS())) 1691 return true; 1692 return CheckAddressConstantExpression(Exp->getRHS()); 1693 } 1694 case Expr::AddrLabelExprClass: 1695 return false; 1696 } 1697} 1698 1699static const Expr* FindExpressionBaseAddress(const Expr* E); 1700 1701static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1702 switch (E->getStmtClass()) { 1703 default: 1704 return E; 1705 case Expr::ParenExprClass: { 1706 const ParenExpr* PE = cast<ParenExpr>(E); 1707 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1708 } 1709 case Expr::MemberExprClass: { 1710 const MemberExpr *M = cast<MemberExpr>(E); 1711 if (M->isArrow()) 1712 return FindExpressionBaseAddress(M->getBase()); 1713 return FindExpressionBaseAddressLValue(M->getBase()); 1714 } 1715 case Expr::ArraySubscriptExprClass: { 1716 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1717 return FindExpressionBaseAddress(ASE->getBase()); 1718 } 1719 case Expr::UnaryOperatorClass: { 1720 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1721 1722 if (Exp->getOpcode() == UnaryOperator::Deref) 1723 return FindExpressionBaseAddress(Exp->getSubExpr()); 1724 1725 return E; 1726 } 1727 } 1728} 1729 1730static const Expr* FindExpressionBaseAddress(const Expr* E) { 1731 switch (E->getStmtClass()) { 1732 default: 1733 return E; 1734 case Expr::ParenExprClass: { 1735 const ParenExpr* PE = cast<ParenExpr>(E); 1736 return FindExpressionBaseAddress(PE->getSubExpr()); 1737 } 1738 case Expr::UnaryOperatorClass: { 1739 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1740 1741 // C99 6.6p9 1742 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1743 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1744 1745 if (Exp->getOpcode() == UnaryOperator::Extension) 1746 return FindExpressionBaseAddress(Exp->getSubExpr()); 1747 1748 return E; 1749 } 1750 case Expr::BinaryOperatorClass: { 1751 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1752 1753 Expr *PExp = Exp->getLHS(); 1754 Expr *IExp = Exp->getRHS(); 1755 if (IExp->getType()->isPointerType()) 1756 std::swap(PExp, IExp); 1757 1758 return FindExpressionBaseAddress(PExp); 1759 } 1760 case Expr::ImplicitCastExprClass: { 1761 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1762 1763 // Check for implicit promotion 1764 if (SubExpr->getType()->isFunctionType() || 1765 SubExpr->getType()->isArrayType()) 1766 return FindExpressionBaseAddressLValue(SubExpr); 1767 1768 // Check for pointer->pointer cast 1769 if (SubExpr->getType()->isPointerType()) 1770 return FindExpressionBaseAddress(SubExpr); 1771 1772 // We assume that we have an arithmetic expression here; 1773 // if we don't, we'll figure it out later 1774 return 0; 1775 } 1776 case Expr::CStyleCastExprClass: { 1777 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1778 1779 // Check for pointer->pointer cast 1780 if (SubExpr->getType()->isPointerType()) 1781 return FindExpressionBaseAddress(SubExpr); 1782 1783 // We assume that we have an arithmetic expression here; 1784 // if we don't, we'll figure it out later 1785 return 0; 1786 } 1787 } 1788} 1789 1790bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1791 switch (Init->getStmtClass()) { 1792 default: 1793 InitializerElementNotConstant(Init); 1794 return true; 1795 case Expr::ParenExprClass: { 1796 const ParenExpr* PE = cast<ParenExpr>(Init); 1797 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1798 } 1799 case Expr::FloatingLiteralClass: 1800 case Expr::IntegerLiteralClass: 1801 case Expr::CharacterLiteralClass: 1802 case Expr::ImaginaryLiteralClass: 1803 case Expr::TypesCompatibleExprClass: 1804 case Expr::CXXBoolLiteralExprClass: 1805 return false; 1806 case Expr::CallExprClass: 1807 case Expr::CXXOperatorCallExprClass: { 1808 const CallExpr *CE = cast<CallExpr>(Init); 1809 1810 // Allow any constant foldable calls to builtins. 1811 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1812 return false; 1813 1814 InitializerElementNotConstant(Init); 1815 return true; 1816 } 1817 case Expr::DeclRefExprClass: { 1818 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1819 if (isa<EnumConstantDecl>(D)) 1820 return false; 1821 InitializerElementNotConstant(Init); 1822 return true; 1823 } 1824 case Expr::CompoundLiteralExprClass: 1825 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1826 // but vectors are allowed to be magic. 1827 if (Init->getType()->isVectorType()) 1828 return false; 1829 InitializerElementNotConstant(Init); 1830 return true; 1831 case Expr::UnaryOperatorClass: { 1832 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1833 1834 switch (Exp->getOpcode()) { 1835 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1836 // See C99 6.6p3. 1837 default: 1838 InitializerElementNotConstant(Init); 1839 return true; 1840 case UnaryOperator::OffsetOf: 1841 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1842 return false; 1843 InitializerElementNotConstant(Init); 1844 return true; 1845 case UnaryOperator::Extension: 1846 case UnaryOperator::LNot: 1847 case UnaryOperator::Plus: 1848 case UnaryOperator::Minus: 1849 case UnaryOperator::Not: 1850 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1851 } 1852 } 1853 case Expr::SizeOfAlignOfExprClass: { 1854 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 1855 // Special check for void types, which are allowed as an extension 1856 if (Exp->getTypeOfArgument()->isVoidType()) 1857 return false; 1858 // alignof always evaluates to a constant. 1859 // FIXME: is sizeof(int[3.0]) a constant expression? 1860 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 1861 InitializerElementNotConstant(Init); 1862 return true; 1863 } 1864 return false; 1865 } 1866 case Expr::BinaryOperatorClass: { 1867 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1868 1869 if (Exp->getLHS()->getType()->isArithmeticType() && 1870 Exp->getRHS()->getType()->isArithmeticType()) { 1871 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1872 CheckArithmeticConstantExpression(Exp->getRHS()); 1873 } 1874 1875 if (Exp->getLHS()->getType()->isPointerType() && 1876 Exp->getRHS()->getType()->isPointerType()) { 1877 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1878 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1879 1880 // Only allow a null (constant integer) base; we could 1881 // allow some additional cases if necessary, but this 1882 // is sufficient to cover offsetof-like constructs. 1883 if (!LHSBase && !RHSBase) { 1884 return CheckAddressConstantExpression(Exp->getLHS()) || 1885 CheckAddressConstantExpression(Exp->getRHS()); 1886 } 1887 } 1888 1889 InitializerElementNotConstant(Init); 1890 return true; 1891 } 1892 case Expr::ImplicitCastExprClass: 1893 case Expr::CStyleCastExprClass: { 1894 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1895 if (SubExpr->getType()->isArithmeticType()) 1896 return CheckArithmeticConstantExpression(SubExpr); 1897 1898 if (SubExpr->getType()->isPointerType()) { 1899 const Expr* Base = FindExpressionBaseAddress(SubExpr); 1900 // If the pointer has a null base, this is an offsetof-like construct 1901 if (!Base) 1902 return CheckAddressConstantExpression(SubExpr); 1903 } 1904 1905 InitializerElementNotConstant(Init); 1906 return true; 1907 } 1908 case Expr::ConditionalOperatorClass: { 1909 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1910 1911 // If GNU extensions are disabled, we require all operands to be arithmetic 1912 // constant expressions. 1913 if (getLangOptions().NoExtensions) { 1914 return CheckArithmeticConstantExpression(Exp->getCond()) || 1915 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 1916 CheckArithmeticConstantExpression(Exp->getRHS()); 1917 } 1918 1919 // Otherwise, we have to emulate some of the behavior of fold here. 1920 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 1921 // because it can constant fold things away. To retain compatibility with 1922 // GCC code, we see if we can fold the condition to a constant (which we 1923 // should always be able to do in theory). If so, we only require the 1924 // specified arm of the conditional to be a constant. This is a horrible 1925 // hack, but is require by real world code that uses __builtin_constant_p. 1926 Expr::EvalResult EvalResult; 1927 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 1928 EvalResult.HasSideEffects) { 1929 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 1930 // won't be able to either. Use it to emit the diagnostic though. 1931 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 1932 assert(Res && "Evaluate couldn't evaluate this constant?"); 1933 return Res; 1934 } 1935 1936 // Verify that the side following the condition is also a constant. 1937 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 1938 if (EvalResult.Val.getInt() == 0) 1939 std::swap(TrueSide, FalseSide); 1940 1941 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 1942 return true; 1943 1944 // Okay, the evaluated side evaluates to a constant, so we accept this. 1945 // Check to see if the other side is obviously not a constant. If so, 1946 // emit a warning that this is a GNU extension. 1947 if (FalseSide && !FalseSide->isEvaluatable(Context)) 1948 Diag(Init->getExprLoc(), 1949 diag::ext_typecheck_expression_not_constant_but_accepted) 1950 << FalseSide->getSourceRange(); 1951 return false; 1952 } 1953 } 1954} 1955 1956bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1957 Expr::EvalResult Result; 1958 1959 Init = Init->IgnoreParens(); 1960 1961 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 1962 return false; 1963 1964 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1965 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1966 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1967 1968 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 1969 return CheckForConstantInitializer(e->getInitializer(), DclT); 1970 1971 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1972 unsigned numInits = Exp->getNumInits(); 1973 for (unsigned i = 0; i < numInits; i++) { 1974 // FIXME: Need to get the type of the declaration for C++, 1975 // because it could be a reference? 1976 if (CheckForConstantInitializer(Exp->getInit(i), 1977 Exp->getInit(i)->getType())) 1978 return true; 1979 } 1980 return false; 1981 } 1982 1983 // FIXME: We can probably remove some of this code below, now that 1984 // Expr::Evaluate is doing the heavy lifting for scalars. 1985 1986 if (Init->isNullPointerConstant(Context)) 1987 return false; 1988 if (Init->getType()->isArithmeticType()) { 1989 QualType InitTy = Context.getCanonicalType(Init->getType()) 1990 .getUnqualifiedType(); 1991 if (InitTy == Context.BoolTy) { 1992 // Special handling for pointers implicitly cast to bool; 1993 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1994 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1995 Expr* SubE = ICE->getSubExpr(); 1996 if (SubE->getType()->isPointerType() || 1997 SubE->getType()->isArrayType() || 1998 SubE->getType()->isFunctionType()) { 1999 return CheckAddressConstantExpression(Init); 2000 } 2001 } 2002 } else if (InitTy->isIntegralType()) { 2003 Expr* SubE = 0; 2004 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2005 SubE = CE->getSubExpr(); 2006 // Special check for pointer cast to int; we allow as an extension 2007 // an address constant cast to an integer if the integer 2008 // is of an appropriate width (this sort of code is apparently used 2009 // in some places). 2010 // FIXME: Add pedwarn? 2011 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2012 if (SubE && (SubE->getType()->isPointerType() || 2013 SubE->getType()->isArrayType() || 2014 SubE->getType()->isFunctionType())) { 2015 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2016 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2017 if (IntWidth >= PointerWidth) 2018 return CheckAddressConstantExpression(Init); 2019 } 2020 } 2021 2022 return CheckArithmeticConstantExpression(Init); 2023 } 2024 2025 if (Init->getType()->isPointerType()) 2026 return CheckAddressConstantExpression(Init); 2027 2028 // An array type at the top level that isn't an init-list must 2029 // be a string literal 2030 if (Init->getType()->isArrayType()) 2031 return false; 2032 2033 if (Init->getType()->isFunctionType()) 2034 return false; 2035 2036 // Allow block exprs at top level. 2037 if (Init->getType()->isBlockPointerType()) 2038 return false; 2039 2040 InitializerElementNotConstant(Init); 2041 return true; 2042} 2043 2044void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2045 Decl *RealDecl = static_cast<Decl *>(dcl); 2046 Expr *Init = static_cast<Expr *>(init.release()); 2047 assert(Init && "missing initializer"); 2048 2049 // If there is no declaration, there was an error parsing it. Just ignore 2050 // the initializer. 2051 if (RealDecl == 0) { 2052 delete Init; 2053 return; 2054 } 2055 2056 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2057 if (!VDecl) { 2058 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2059 diag::err_illegal_initializer); 2060 RealDecl->setInvalidDecl(); 2061 return; 2062 } 2063 // Get the decls type and save a reference for later, since 2064 // CheckInitializerTypes may change it. 2065 QualType DclT = VDecl->getType(), SavT = DclT; 2066 if (VDecl->isBlockVarDecl()) { 2067 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2068 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2069 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2070 VDecl->setInvalidDecl(); 2071 } else if (!VDecl->isInvalidDecl()) { 2072 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2073 VDecl->getDeclName())) 2074 VDecl->setInvalidDecl(); 2075 2076 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2077 if (!getLangOptions().CPlusPlus) { 2078 if (SC == VarDecl::Static) // C99 6.7.8p4. 2079 CheckForConstantInitializer(Init, DclT); 2080 } 2081 } 2082 } else if (VDecl->isFileVarDecl()) { 2083 if (VDecl->getStorageClass() == VarDecl::Extern) 2084 Diag(VDecl->getLocation(), diag::warn_extern_init); 2085 if (!VDecl->isInvalidDecl()) 2086 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2087 VDecl->getDeclName())) 2088 VDecl->setInvalidDecl(); 2089 2090 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2091 if (!getLangOptions().CPlusPlus) { 2092 // C99 6.7.8p4. All file scoped initializers need to be constant. 2093 CheckForConstantInitializer(Init, DclT); 2094 } 2095 } 2096 // If the type changed, it means we had an incomplete type that was 2097 // completed by the initializer. For example: 2098 // int ary[] = { 1, 3, 5 }; 2099 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2100 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2101 VDecl->setType(DclT); 2102 Init->setType(DclT); 2103 } 2104 2105 // Attach the initializer to the decl. 2106 VDecl->setInit(Init); 2107 return; 2108} 2109 2110void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2111 Decl *RealDecl = static_cast<Decl *>(dcl); 2112 2113 // If there is no declaration, there was an error parsing it. Just ignore it. 2114 if (RealDecl == 0) 2115 return; 2116 2117 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2118 QualType Type = Var->getType(); 2119 // C++ [dcl.init.ref]p3: 2120 // The initializer can be omitted for a reference only in a 2121 // parameter declaration (8.3.5), in the declaration of a 2122 // function return type, in the declaration of a class member 2123 // within its class declaration (9.2), and where the extern 2124 // specifier is explicitly used. 2125 if (Type->isReferenceType() && 2126 Var->getStorageClass() != VarDecl::Extern && 2127 Var->getStorageClass() != VarDecl::PrivateExtern) { 2128 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2129 << Var->getDeclName() 2130 << SourceRange(Var->getLocation(), Var->getLocation()); 2131 Var->setInvalidDecl(); 2132 return; 2133 } 2134 2135 // C++ [dcl.init]p9: 2136 // 2137 // If no initializer is specified for an object, and the object 2138 // is of (possibly cv-qualified) non-POD class type (or array 2139 // thereof), the object shall be default-initialized; if the 2140 // object is of const-qualified type, the underlying class type 2141 // shall have a user-declared default constructor. 2142 if (getLangOptions().CPlusPlus) { 2143 QualType InitType = Type; 2144 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2145 InitType = Array->getElementType(); 2146 if (Var->getStorageClass() != VarDecl::Extern && 2147 Var->getStorageClass() != VarDecl::PrivateExtern && 2148 InitType->isRecordType()) { 2149 const CXXConstructorDecl *Constructor 2150 = PerformInitializationByConstructor(InitType, 0, 0, 2151 Var->getLocation(), 2152 SourceRange(Var->getLocation(), 2153 Var->getLocation()), 2154 Var->getDeclName(), 2155 IK_Default); 2156 if (!Constructor) 2157 Var->setInvalidDecl(); 2158 } 2159 } 2160 2161#if 0 2162 // FIXME: Temporarily disabled because we are not properly parsing 2163 // linkage specifications on declarations, e.g., 2164 // 2165 // extern "C" const CGPoint CGPointerZero; 2166 // 2167 // C++ [dcl.init]p9: 2168 // 2169 // If no initializer is specified for an object, and the 2170 // object is of (possibly cv-qualified) non-POD class type (or 2171 // array thereof), the object shall be default-initialized; if 2172 // the object is of const-qualified type, the underlying class 2173 // type shall have a user-declared default 2174 // constructor. Otherwise, if no initializer is specified for 2175 // an object, the object and its subobjects, if any, have an 2176 // indeterminate initial value; if the object or any of its 2177 // subobjects are of const-qualified type, the program is 2178 // ill-formed. 2179 // 2180 // This isn't technically an error in C, so we don't diagnose it. 2181 // 2182 // FIXME: Actually perform the POD/user-defined default 2183 // constructor check. 2184 if (getLangOptions().CPlusPlus && 2185 Context.getCanonicalType(Type).isConstQualified() && 2186 Var->getStorageClass() != VarDecl::Extern) 2187 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2188 << Var->getName() 2189 << SourceRange(Var->getLocation(), Var->getLocation()); 2190#endif 2191 } 2192} 2193 2194/// The declarators are chained together backwards, reverse the list. 2195Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2196 // Often we have single declarators, handle them quickly. 2197 Decl *GroupDecl = static_cast<Decl*>(group); 2198 if (GroupDecl == 0) 2199 return 0; 2200 2201 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2202 ScopedDecl *NewGroup = 0; 2203 if (Group->getNextDeclarator() == 0) 2204 NewGroup = Group; 2205 else { // reverse the list. 2206 while (Group) { 2207 ScopedDecl *Next = Group->getNextDeclarator(); 2208 Group->setNextDeclarator(NewGroup); 2209 NewGroup = Group; 2210 Group = Next; 2211 } 2212 } 2213 // Perform semantic analysis that depends on having fully processed both 2214 // the declarator and initializer. 2215 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2216 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2217 if (!IDecl) 2218 continue; 2219 QualType T = IDecl->getType(); 2220 2221 if (T->isVariableArrayType()) { 2222 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2223 2224 // FIXME: This won't give the correct result for 2225 // int a[10][n]; 2226 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2227 if (IDecl->isFileVarDecl()) { 2228 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2229 SizeRange; 2230 2231 IDecl->setInvalidDecl(); 2232 } else { 2233 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2234 // static storage duration, it shall not have a variable length array. 2235 if (IDecl->getStorageClass() == VarDecl::Static) { 2236 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2237 << SizeRange; 2238 IDecl->setInvalidDecl(); 2239 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2240 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2241 << SizeRange; 2242 IDecl->setInvalidDecl(); 2243 } 2244 } 2245 } else if (T->isVariablyModifiedType()) { 2246 if (IDecl->isFileVarDecl()) { 2247 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2248 IDecl->setInvalidDecl(); 2249 } else { 2250 if (IDecl->getStorageClass() == VarDecl::Extern) { 2251 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2252 IDecl->setInvalidDecl(); 2253 } 2254 } 2255 } 2256 2257 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2258 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2259 if (IDecl->isBlockVarDecl() && 2260 IDecl->getStorageClass() != VarDecl::Extern) { 2261 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2262 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2263 IDecl->setInvalidDecl(); 2264 } 2265 } 2266 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2267 // object that has file scope without an initializer, and without a 2268 // storage-class specifier or with the storage-class specifier "static", 2269 // constitutes a tentative definition. Note: A tentative definition with 2270 // external linkage is valid (C99 6.2.2p5). 2271 if (isTentativeDefinition(IDecl)) { 2272 if (T->isIncompleteArrayType()) { 2273 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2274 // array to be completed. Don't issue a diagnostic. 2275 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2276 // C99 6.9.2p3: If the declaration of an identifier for an object is 2277 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2278 // declared type shall not be an incomplete type. 2279 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2280 IDecl->setInvalidDecl(); 2281 } 2282 } 2283 if (IDecl->isFileVarDecl()) 2284 CheckForFileScopedRedefinitions(S, IDecl); 2285 } 2286 return NewGroup; 2287} 2288 2289/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2290/// to introduce parameters into function prototype scope. 2291Sema::DeclTy * 2292Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2293 const DeclSpec &DS = D.getDeclSpec(); 2294 2295 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2296 VarDecl::StorageClass StorageClass = VarDecl::None; 2297 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2298 StorageClass = VarDecl::Register; 2299 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2300 Diag(DS.getStorageClassSpecLoc(), 2301 diag::err_invalid_storage_class_in_func_decl); 2302 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2303 } 2304 if (DS.isThreadSpecified()) { 2305 Diag(DS.getThreadSpecLoc(), 2306 diag::err_invalid_storage_class_in_func_decl); 2307 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2308 } 2309 2310 // Check that there are no default arguments inside the type of this 2311 // parameter (C++ only). 2312 if (getLangOptions().CPlusPlus) 2313 CheckExtraCXXDefaultArguments(D); 2314 2315 // In this context, we *do not* check D.getInvalidType(). If the declarator 2316 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2317 // though it will not reflect the user specified type. 2318 QualType parmDeclType = GetTypeForDeclarator(D, S); 2319 2320 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2321 2322 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2323 // Can this happen for params? We already checked that they don't conflict 2324 // among each other. Here they can only shadow globals, which is ok. 2325 IdentifierInfo *II = D.getIdentifier(); 2326 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2327 if (PrevDecl->isTemplateParameter()) { 2328 // Maybe we will complain about the shadowed template parameter. 2329 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2330 // Just pretend that we didn't see the previous declaration. 2331 PrevDecl = 0; 2332 } else if (S->isDeclScope(PrevDecl)) { 2333 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2334 2335 // Recover by removing the name 2336 II = 0; 2337 D.SetIdentifier(0, D.getIdentifierLoc()); 2338 } 2339 } 2340 2341 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2342 // Doing the promotion here has a win and a loss. The win is the type for 2343 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2344 // code generator). The loss is the orginal type isn't preserved. For example: 2345 // 2346 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2347 // int blockvardecl[5]; 2348 // sizeof(parmvardecl); // size == 4 2349 // sizeof(blockvardecl); // size == 20 2350 // } 2351 // 2352 // For expressions, all implicit conversions are captured using the 2353 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2354 // 2355 // FIXME: If a source translation tool needs to see the original type, then 2356 // we need to consider storing both types (in ParmVarDecl)... 2357 // 2358 if (parmDeclType->isArrayType()) { 2359 // int x[restrict 4] -> int *restrict 2360 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2361 } else if (parmDeclType->isFunctionType()) 2362 parmDeclType = Context.getPointerType(parmDeclType); 2363 2364 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2365 D.getIdentifierLoc(), II, 2366 parmDeclType, StorageClass, 2367 0, 0); 2368 2369 if (D.getInvalidType()) 2370 New->setInvalidDecl(); 2371 2372 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2373 if (D.getCXXScopeSpec().isSet()) { 2374 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2375 << D.getCXXScopeSpec().getRange(); 2376 New->setInvalidDecl(); 2377 } 2378 2379 // Add the parameter declaration into this scope. 2380 S->AddDecl(New); 2381 if (II) 2382 IdResolver.AddDecl(New); 2383 2384 ProcessDeclAttributes(New, D); 2385 return New; 2386 2387} 2388 2389Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2390 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2391 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2392 "Not a function declarator!"); 2393 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2394 2395 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2396 // for a K&R function. 2397 if (!FTI.hasPrototype) { 2398 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2399 if (FTI.ArgInfo[i].Param == 0) { 2400 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2401 << FTI.ArgInfo[i].Ident; 2402 // Implicitly declare the argument as type 'int' for lack of a better 2403 // type. 2404 DeclSpec DS; 2405 const char* PrevSpec; // unused 2406 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2407 PrevSpec); 2408 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2409 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2410 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2411 } 2412 } 2413 } else { 2414 // FIXME: Diagnose arguments without names in C. 2415 } 2416 2417 Scope *ParentScope = FnBodyScope->getParent(); 2418 2419 return ActOnStartOfFunctionDef(FnBodyScope, 2420 ActOnDeclarator(ParentScope, D, 0, 2421 /*IsFunctionDefinition=*/true)); 2422} 2423 2424Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2425 Decl *decl = static_cast<Decl*>(D); 2426 FunctionDecl *FD = cast<FunctionDecl>(decl); 2427 2428 // See if this is a redefinition. 2429 const FunctionDecl *Definition; 2430 if (FD->getBody(Definition)) { 2431 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2432 Diag(Definition->getLocation(), diag::note_previous_definition); 2433 } 2434 2435 PushDeclContext(FnBodyScope, FD); 2436 2437 // Check the validity of our function parameters 2438 CheckParmsForFunctionDef(FD); 2439 2440 // Introduce our parameters into the function scope 2441 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2442 ParmVarDecl *Param = FD->getParamDecl(p); 2443 // If this has an identifier, add it to the scope stack. 2444 if (Param->getIdentifier()) 2445 PushOnScopeChains(Param, FnBodyScope); 2446 } 2447 2448 // Checking attributes of current function definition 2449 // dllimport attribute. 2450 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2451 // dllimport attribute cannot be applied to definition. 2452 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2453 Diag(FD->getLocation(), 2454 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2455 << "dllimport"; 2456 FD->setInvalidDecl(); 2457 return FD; 2458 } else { 2459 // If a symbol previously declared dllimport is later defined, the 2460 // attribute is ignored in subsequent references, and a warning is 2461 // emitted. 2462 Diag(FD->getLocation(), 2463 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2464 << FD->getNameAsCString() << "dllimport"; 2465 } 2466 } 2467 return FD; 2468} 2469 2470Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2471 Decl *dcl = static_cast<Decl *>(D); 2472 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2473 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2474 FD->setBody(Body); 2475 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2476 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2477 MD->setBody((Stmt*)Body); 2478 } else 2479 return 0; 2480 PopDeclContext(); 2481 // Verify and clean out per-function state. 2482 2483 // Check goto/label use. 2484 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2485 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2486 // Verify that we have no forward references left. If so, there was a goto 2487 // or address of a label taken, but no definition of it. Label fwd 2488 // definitions are indicated with a null substmt. 2489 if (I->second->getSubStmt() == 0) { 2490 LabelStmt *L = I->second; 2491 // Emit error. 2492 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2493 2494 // At this point, we have gotos that use the bogus label. Stitch it into 2495 // the function body so that they aren't leaked and that the AST is well 2496 // formed. 2497 if (Body) { 2498 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2499 cast<CompoundStmt>(Body)->push_back(L); 2500 } else { 2501 // The whole function wasn't parsed correctly, just delete this. 2502 delete L; 2503 } 2504 } 2505 } 2506 LabelMap.clear(); 2507 2508 return D; 2509} 2510 2511/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2512/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2513ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2514 IdentifierInfo &II, Scope *S) { 2515 // Extension in C99. Legal in C90, but warn about it. 2516 if (getLangOptions().C99) 2517 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2518 else 2519 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2520 2521 // FIXME: handle stuff like: 2522 // void foo() { extern float X(); } 2523 // void bar() { X(); } <-- implicit decl for X in another scope. 2524 2525 // Set a Declarator for the implicit definition: int foo(); 2526 const char *Dummy; 2527 DeclSpec DS; 2528 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2529 Error = Error; // Silence warning. 2530 assert(!Error && "Error setting up implicit decl!"); 2531 Declarator D(DS, Declarator::BlockContext); 2532 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2533 D.SetIdentifier(&II, Loc); 2534 2535 // Insert this function into translation-unit scope. 2536 2537 DeclContext *PrevDC = CurContext; 2538 CurContext = Context.getTranslationUnitDecl(); 2539 2540 FunctionDecl *FD = 2541 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2542 FD->setImplicit(); 2543 2544 CurContext = PrevDC; 2545 2546 return FD; 2547} 2548 2549 2550TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2551 ScopedDecl *LastDeclarator) { 2552 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2553 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2554 2555 // Scope manipulation handled by caller. 2556 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2557 D.getIdentifierLoc(), 2558 D.getIdentifier(), 2559 T, LastDeclarator); 2560 if (D.getInvalidType()) 2561 NewTD->setInvalidDecl(); 2562 return NewTD; 2563} 2564 2565/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2566/// former case, Name will be non-null. In the later case, Name will be null. 2567/// TagType indicates what kind of tag this is. TK indicates whether this is a 2568/// reference/declaration/definition of a tag. 2569Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2570 SourceLocation KWLoc, const CXXScopeSpec &SS, 2571 IdentifierInfo *Name, SourceLocation NameLoc, 2572 AttributeList *Attr, 2573 MultiTemplateParamsArg TemplateParameterLists) { 2574 // If this is not a definition, it must have a name. 2575 assert((Name != 0 || TK == TK_Definition) && 2576 "Nameless record must be a definition!"); 2577 2578 TagDecl::TagKind Kind; 2579 switch (TagType) { 2580 default: assert(0 && "Unknown tag type!"); 2581 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2582 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2583 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2584 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2585 } 2586 2587 DeclContext *DC = CurContext; 2588 ScopedDecl *PrevDecl = 0; 2589 2590 if (Name && SS.isNotEmpty()) { 2591 // We have a nested-name tag ('struct foo::bar'). 2592 2593 // Check for invalid 'foo::'. 2594 if (SS.isInvalid()) { 2595 Name = 0; 2596 goto CreateNewDecl; 2597 } 2598 2599 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2600 // Look-up name inside 'foo::'. 2601 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2602 2603 // A tag 'foo::bar' must already exist. 2604 if (PrevDecl == 0) { 2605 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2606 Name = 0; 2607 goto CreateNewDecl; 2608 } 2609 } else { 2610 // If this is a named struct, check to see if there was a previous forward 2611 // declaration or definition. 2612 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2613 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2614 } 2615 2616 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2617 // Maybe we will complain about the shadowed template parameter. 2618 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2619 // Just pretend that we didn't see the previous declaration. 2620 PrevDecl = 0; 2621 } 2622 2623 if (PrevDecl) { 2624 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2625 "unexpected Decl type"); 2626 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2627 // If this is a use of a previous tag, or if the tag is already declared 2628 // in the same scope (so that the definition/declaration completes or 2629 // rementions the tag), reuse the decl. 2630 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2631 // Make sure that this wasn't declared as an enum and now used as a 2632 // struct or something similar. 2633 if (PrevTagDecl->getTagKind() != Kind) { 2634 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2635 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2636 // Recover by making this an anonymous redefinition. 2637 Name = 0; 2638 PrevDecl = 0; 2639 } else { 2640 // If this is a use, just return the declaration we found. 2641 2642 // FIXME: In the future, return a variant or some other clue 2643 // for the consumer of this Decl to know it doesn't own it. 2644 // For our current ASTs this shouldn't be a problem, but will 2645 // need to be changed with DeclGroups. 2646 if (TK == TK_Reference) 2647 return PrevDecl; 2648 2649 // Diagnose attempts to redefine a tag. 2650 if (TK == TK_Definition) { 2651 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2652 Diag(NameLoc, diag::err_redefinition) << Name; 2653 Diag(Def->getLocation(), diag::note_previous_definition); 2654 // If this is a redefinition, recover by making this struct be 2655 // anonymous, which will make any later references get the previous 2656 // definition. 2657 Name = 0; 2658 PrevDecl = 0; 2659 } 2660 // Okay, this is definition of a previously declared or referenced 2661 // tag PrevDecl. We're going to create a new Decl for it. 2662 } 2663 } 2664 // If we get here we have (another) forward declaration or we 2665 // have a definition. Just create a new decl. 2666 } else { 2667 // If we get here, this is a definition of a new tag type in a nested 2668 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2669 // new decl/type. We set PrevDecl to NULL so that the entities 2670 // have distinct types. 2671 PrevDecl = 0; 2672 } 2673 // If we get here, we're going to create a new Decl. If PrevDecl 2674 // is non-NULL, it's a definition of the tag declared by 2675 // PrevDecl. If it's NULL, we have a new definition. 2676 } else { 2677 // PrevDecl is a namespace. 2678 if (isDeclInScope(PrevDecl, DC, S)) { 2679 // The tag name clashes with a namespace name, issue an error and 2680 // recover by making this tag be anonymous. 2681 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2682 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2683 Name = 0; 2684 PrevDecl = 0; 2685 } else { 2686 // The existing declaration isn't relevant to us; we're in a 2687 // new scope, so clear out the previous declaration. 2688 PrevDecl = 0; 2689 } 2690 } 2691 } 2692 2693CreateNewDecl: 2694 2695 // If there is an identifier, use the location of the identifier as the 2696 // location of the decl, otherwise use the location of the struct/union 2697 // keyword. 2698 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2699 2700 // Otherwise, create a new declaration. If there is a previous 2701 // declaration of the same entity, the two will be linked via 2702 // PrevDecl. 2703 TagDecl *New; 2704 if (Kind == TagDecl::TK_enum) { 2705 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2706 // enum X { A, B, C } D; D should chain to X. 2707 New = EnumDecl::Create(Context, DC, Loc, Name, 2708 cast_or_null<EnumDecl>(PrevDecl)); 2709 // If this is an undefined enum, warn. 2710 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2711 } else { 2712 // struct/union/class 2713 2714 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2715 // struct X { int A; } D; D should chain to X. 2716 if (getLangOptions().CPlusPlus) 2717 // FIXME: Look for a way to use RecordDecl for simple structs. 2718 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2719 cast_or_null<CXXRecordDecl>(PrevDecl)); 2720 else 2721 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2722 cast_or_null<RecordDecl>(PrevDecl)); 2723 } 2724 2725 if (Kind != TagDecl::TK_enum) { 2726 // Handle #pragma pack: if the #pragma pack stack has non-default 2727 // alignment, make up a packed attribute for this decl. These 2728 // attributes are checked when the ASTContext lays out the 2729 // structure. 2730 // 2731 // It is important for implementing the correct semantics that this 2732 // happen here (in act on tag decl). The #pragma pack stack is 2733 // maintained as a result of parser callbacks which can occur at 2734 // many points during the parsing of a struct declaration (because 2735 // the #pragma tokens are effectively skipped over during the 2736 // parsing of the struct). 2737 if (unsigned Alignment = PackContext.getAlignment()) 2738 New->addAttr(new PackedAttr(Alignment * 8)); 2739 } 2740 2741 if (Attr) 2742 ProcessDeclAttributeList(New, Attr); 2743 2744 // Set the lexical context. If the tag has a C++ scope specifier, the 2745 // lexical context will be different from the semantic context. 2746 New->setLexicalDeclContext(CurContext); 2747 2748 // If this has an identifier, add it to the scope stack. 2749 if (Name) { 2750 // The scope passed in may not be a decl scope. Zip up the scope tree until 2751 // we find one that is. 2752 while ((S->getFlags() & Scope::DeclScope) == 0) 2753 S = S->getParent(); 2754 2755 // Add it to the decl chain. 2756 PushOnScopeChains(New, S); 2757 } 2758 2759 return New; 2760} 2761 2762 2763/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2764/// types into constant array types in certain situations which would otherwise 2765/// be errors (for GCC compatibility). 2766static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2767 ASTContext &Context) { 2768 // This method tries to turn a variable array into a constant 2769 // array even when the size isn't an ICE. This is necessary 2770 // for compatibility with code that depends on gcc's buggy 2771 // constant expression folding, like struct {char x[(int)(char*)2];} 2772 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2773 if (!VLATy) return QualType(); 2774 2775 Expr::EvalResult EvalResult; 2776 if (!VLATy->getSizeExpr() || 2777 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 2778 return QualType(); 2779 2780 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 2781 llvm::APSInt &Res = EvalResult.Val.getInt(); 2782 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 2783 return Context.getConstantArrayType(VLATy->getElementType(), 2784 Res, ArrayType::Normal, 0); 2785 return QualType(); 2786} 2787 2788bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 2789 QualType FieldTy, const Expr *BitWidth) { 2790 // FIXME: 6.7.2.1p4 - verify the field type. 2791 2792 llvm::APSInt Value; 2793 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 2794 return true; 2795 2796 // Zero-width bitfield is ok for anonymous field. 2797 if (Value == 0 && FieldName) 2798 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 2799 2800 if (Value.isNegative()) 2801 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 2802 2803 uint64_t TypeSize = Context.getTypeSize(FieldTy); 2804 // FIXME: We won't need the 0 size once we check that the field type is valid. 2805 if (TypeSize && Value.getZExtValue() > TypeSize) 2806 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 2807 << FieldName << (unsigned)TypeSize; 2808 2809 return false; 2810} 2811 2812/// ActOnField - Each field of a struct/union/class is passed into this in order 2813/// to create a FieldDecl object for it. 2814Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 2815 SourceLocation DeclStart, 2816 Declarator &D, ExprTy *BitfieldWidth) { 2817 IdentifierInfo *II = D.getIdentifier(); 2818 Expr *BitWidth = (Expr*)BitfieldWidth; 2819 SourceLocation Loc = DeclStart; 2820 RecordDecl *Record = (RecordDecl *)TagD; 2821 if (II) Loc = D.getIdentifierLoc(); 2822 2823 // FIXME: Unnamed fields can be handled in various different ways, for 2824 // example, unnamed unions inject all members into the struct namespace! 2825 2826 QualType T = GetTypeForDeclarator(D, S); 2827 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2828 bool InvalidDecl = false; 2829 2830 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2831 // than a variably modified type. 2832 if (T->isVariablyModifiedType()) { 2833 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 2834 if (!FixedTy.isNull()) { 2835 Diag(Loc, diag::warn_illegal_constant_array_size); 2836 T = FixedTy; 2837 } else { 2838 Diag(Loc, diag::err_typecheck_field_variable_size); 2839 T = Context.IntTy; 2840 InvalidDecl = true; 2841 } 2842 } 2843 2844 if (BitWidth) { 2845 if (VerifyBitField(Loc, II, T, BitWidth)) 2846 InvalidDecl = true; 2847 } else { 2848 // Not a bitfield. 2849 2850 // validate II. 2851 2852 } 2853 2854 // FIXME: Chain fielddecls together. 2855 FieldDecl *NewFD; 2856 2857 // FIXME: We don't want CurContext for C, do we? No, we'll need some 2858 // other way to determine the current RecordDecl. 2859 NewFD = FieldDecl::Create(Context, Record, 2860 Loc, II, T, BitWidth, 2861 D.getDeclSpec().getStorageClassSpec() == 2862 DeclSpec::SCS_mutable, 2863 /*PrevDecl=*/0); 2864 2865 if (getLangOptions().CPlusPlus) 2866 CheckExtraCXXDefaultArguments(D); 2867 2868 ProcessDeclAttributes(NewFD, D); 2869 2870 if (D.getInvalidType() || InvalidDecl) 2871 NewFD->setInvalidDecl(); 2872 2873 if (II && getLangOptions().CPlusPlus) 2874 PushOnScopeChains(NewFD, S); 2875 else 2876 Record->addDecl(Context, NewFD); 2877 2878 return NewFD; 2879} 2880 2881/// TranslateIvarVisibility - Translate visibility from a token ID to an 2882/// AST enum value. 2883static ObjCIvarDecl::AccessControl 2884TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 2885 switch (ivarVisibility) { 2886 default: assert(0 && "Unknown visitibility kind"); 2887 case tok::objc_private: return ObjCIvarDecl::Private; 2888 case tok::objc_public: return ObjCIvarDecl::Public; 2889 case tok::objc_protected: return ObjCIvarDecl::Protected; 2890 case tok::objc_package: return ObjCIvarDecl::Package; 2891 } 2892} 2893 2894/// ActOnIvar - Each ivar field of an objective-c class is passed into this 2895/// in order to create an IvarDecl object for it. 2896Sema::DeclTy *Sema::ActOnIvar(Scope *S, 2897 SourceLocation DeclStart, 2898 Declarator &D, ExprTy *BitfieldWidth, 2899 tok::ObjCKeywordKind Visibility) { 2900 IdentifierInfo *II = D.getIdentifier(); 2901 Expr *BitWidth = (Expr*)BitfieldWidth; 2902 SourceLocation Loc = DeclStart; 2903 if (II) Loc = D.getIdentifierLoc(); 2904 2905 // FIXME: Unnamed fields can be handled in various different ways, for 2906 // example, unnamed unions inject all members into the struct namespace! 2907 2908 QualType T = GetTypeForDeclarator(D, S); 2909 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2910 bool InvalidDecl = false; 2911 2912 if (BitWidth) { 2913 // TODO: Validate. 2914 //printf("WARNING: BITFIELDS IGNORED!\n"); 2915 2916 // 6.7.2.1p3 2917 // 6.7.2.1p4 2918 2919 } else { 2920 // Not a bitfield. 2921 2922 // validate II. 2923 2924 } 2925 2926 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2927 // than a variably modified type. 2928 if (T->isVariablyModifiedType()) { 2929 Diag(Loc, diag::err_typecheck_ivar_variable_size); 2930 InvalidDecl = true; 2931 } 2932 2933 // Get the visibility (access control) for this ivar. 2934 ObjCIvarDecl::AccessControl ac = 2935 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 2936 : ObjCIvarDecl::None; 2937 2938 // Construct the decl. 2939 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 2940 (Expr *)BitfieldWidth); 2941 2942 // Process attributes attached to the ivar. 2943 ProcessDeclAttributes(NewID, D); 2944 2945 if (D.getInvalidType() || InvalidDecl) 2946 NewID->setInvalidDecl(); 2947 2948 return NewID; 2949} 2950 2951void Sema::ActOnFields(Scope* S, 2952 SourceLocation RecLoc, DeclTy *RecDecl, 2953 DeclTy **Fields, unsigned NumFields, 2954 SourceLocation LBrac, SourceLocation RBrac, 2955 AttributeList *Attr) { 2956 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 2957 assert(EnclosingDecl && "missing record or interface decl"); 2958 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 2959 2960 if (Record) 2961 if (RecordDecl* DefRecord = Record->getDefinition(Context)) { 2962 // Diagnose code like: 2963 // struct S { struct S {} X; }; 2964 // We discover this when we complete the outer S. Reject and ignore the 2965 // outer S. 2966 Diag(DefRecord->getLocation(), diag::err_nested_redefinition) 2967 << DefRecord->getDeclName(); 2968 Diag(RecLoc, diag::note_previous_definition); 2969 Record->setInvalidDecl(); 2970 return; 2971 } 2972 2973 // Verify that all the fields are okay. 2974 unsigned NumNamedMembers = 0; 2975 llvm::SmallVector<FieldDecl*, 32> RecFields; 2976 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 2977 2978 for (unsigned i = 0; i != NumFields; ++i) { 2979 2980 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 2981 assert(FD && "missing field decl"); 2982 2983 // Remember all fields. 2984 RecFields.push_back(FD); 2985 2986 // Get the type for the field. 2987 Type *FDTy = FD->getType().getTypePtr(); 2988 2989 // C99 6.7.2.1p2 - A field may not be a function type. 2990 if (FDTy->isFunctionType()) { 2991 Diag(FD->getLocation(), diag::err_field_declared_as_function) 2992 << FD->getDeclName(); 2993 FD->setInvalidDecl(); 2994 EnclosingDecl->setInvalidDecl(); 2995 continue; 2996 } 2997 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 2998 if (FDTy->isIncompleteType()) { 2999 if (!Record) { // Incomplete ivar type is always an error. 3000 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3001 FD->setInvalidDecl(); 3002 EnclosingDecl->setInvalidDecl(); 3003 continue; 3004 } 3005 if (i != NumFields-1 || // ... that the last member ... 3006 !Record->isStruct() || // ... of a structure ... 3007 !FDTy->isArrayType()) { //... may have incomplete array type. 3008 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3009 FD->setInvalidDecl(); 3010 EnclosingDecl->setInvalidDecl(); 3011 continue; 3012 } 3013 if (NumNamedMembers < 1) { //... must have more than named member ... 3014 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3015 << FD->getDeclName(); 3016 FD->setInvalidDecl(); 3017 EnclosingDecl->setInvalidDecl(); 3018 continue; 3019 } 3020 // Okay, we have a legal flexible array member at the end of the struct. 3021 if (Record) 3022 Record->setHasFlexibleArrayMember(true); 3023 } 3024 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3025 /// field of another structure or the element of an array. 3026 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3027 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3028 // If this is a member of a union, then entire union becomes "flexible". 3029 if (Record && Record->isUnion()) { 3030 Record->setHasFlexibleArrayMember(true); 3031 } else { 3032 // If this is a struct/class and this is not the last element, reject 3033 // it. Note that GCC supports variable sized arrays in the middle of 3034 // structures. 3035 if (i != NumFields-1) { 3036 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3037 << FD->getDeclName(); 3038 FD->setInvalidDecl(); 3039 EnclosingDecl->setInvalidDecl(); 3040 continue; 3041 } 3042 // We support flexible arrays at the end of structs in other structs 3043 // as an extension. 3044 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3045 << FD->getDeclName(); 3046 if (Record) 3047 Record->setHasFlexibleArrayMember(true); 3048 } 3049 } 3050 } 3051 /// A field cannot be an Objective-c object 3052 if (FDTy->isObjCInterfaceType()) { 3053 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3054 << FD->getDeclName(); 3055 FD->setInvalidDecl(); 3056 EnclosingDecl->setInvalidDecl(); 3057 continue; 3058 } 3059 // Keep track of the number of named members. 3060 if (IdentifierInfo *II = FD->getIdentifier()) { 3061 // Detect duplicate member names. 3062 if (!FieldIDs.insert(II)) { 3063 Diag(FD->getLocation(), diag::err_duplicate_member) << II; 3064 // Find the previous decl. 3065 SourceLocation PrevLoc; 3066 for (unsigned i = 0; ; ++i) { 3067 assert(i != RecFields.size() && "Didn't find previous def!"); 3068 if (RecFields[i]->getIdentifier() == II) { 3069 PrevLoc = RecFields[i]->getLocation(); 3070 break; 3071 } 3072 } 3073 Diag(PrevLoc, diag::note_previous_definition); 3074 FD->setInvalidDecl(); 3075 EnclosingDecl->setInvalidDecl(); 3076 continue; 3077 } 3078 ++NumNamedMembers; 3079 } 3080 } 3081 3082 // Okay, we successfully defined 'Record'. 3083 if (Record) { 3084 Record->completeDefinition(Context); 3085 // If this is a C++ record, HandleTagDeclDefinition will be invoked in 3086 // Sema::ActOnFinishCXXClassDef. 3087 if (!isa<CXXRecordDecl>(Record)) 3088 Consumer.HandleTagDeclDefinition(Record); 3089 } else { 3090 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3091 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3092 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3093 // Must enforce the rule that ivars in the base classes may not be 3094 // duplicates. 3095 if (ID->getSuperClass()) { 3096 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3097 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3098 ObjCIvarDecl* Ivar = (*IVI); 3099 IdentifierInfo *II = Ivar->getIdentifier(); 3100 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3101 if (prevIvar) { 3102 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3103 Diag(prevIvar->getLocation(), diag::note_previous_definition); 3104 } 3105 } 3106 } 3107 } 3108 else if (ObjCImplementationDecl *IMPDecl = 3109 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3110 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3111 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3112 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3113 } 3114 } 3115 3116 if (Attr) 3117 ProcessDeclAttributeList(Record, Attr); 3118} 3119 3120Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3121 DeclTy *lastEnumConst, 3122 SourceLocation IdLoc, IdentifierInfo *Id, 3123 SourceLocation EqualLoc, ExprTy *val) { 3124 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3125 EnumConstantDecl *LastEnumConst = 3126 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3127 Expr *Val = static_cast<Expr*>(val); 3128 3129 // The scope passed in may not be a decl scope. Zip up the scope tree until 3130 // we find one that is. 3131 while ((S->getFlags() & Scope::DeclScope) == 0) 3132 S = S->getParent(); 3133 3134 // Verify that there isn't already something declared with this name in this 3135 // scope. 3136 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3137 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3138 // Maybe we will complain about the shadowed template parameter. 3139 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3140 // Just pretend that we didn't see the previous declaration. 3141 PrevDecl = 0; 3142 } 3143 3144 if (PrevDecl) { 3145 // When in C++, we may get a TagDecl with the same name; in this case the 3146 // enum constant will 'hide' the tag. 3147 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3148 "Received TagDecl when not in C++!"); 3149 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3150 if (isa<EnumConstantDecl>(PrevDecl)) 3151 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3152 else 3153 Diag(IdLoc, diag::err_redefinition) << Id; 3154 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3155 delete Val; 3156 return 0; 3157 } 3158 } 3159 3160 llvm::APSInt EnumVal(32); 3161 QualType EltTy; 3162 if (Val) { 3163 // Make sure to promote the operand type to int. 3164 UsualUnaryConversions(Val); 3165 3166 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3167 SourceLocation ExpLoc; 3168 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3169 delete Val; 3170 Val = 0; // Just forget about it. 3171 } else { 3172 EltTy = Val->getType(); 3173 } 3174 } 3175 3176 if (!Val) { 3177 if (LastEnumConst) { 3178 // Assign the last value + 1. 3179 EnumVal = LastEnumConst->getInitVal(); 3180 ++EnumVal; 3181 3182 // Check for overflow on increment. 3183 if (EnumVal < LastEnumConst->getInitVal()) 3184 Diag(IdLoc, diag::warn_enum_value_overflow); 3185 3186 EltTy = LastEnumConst->getType(); 3187 } else { 3188 // First value, set to zero. 3189 EltTy = Context.IntTy; 3190 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3191 } 3192 } 3193 3194 EnumConstantDecl *New = 3195 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3196 Val, EnumVal, 3197 LastEnumConst); 3198 3199 // Register this decl in the current scope stack. 3200 PushOnScopeChains(New, S); 3201 3202 // Add this enumerator into the enum itself. 3203 // FIXME: This means that the enumerator is stored in two 3204 // DeclContexts. This is not a long-term solution. 3205 New->setLexicalDeclContext(TheEnumDecl); 3206 TheEnumDecl->addDecl(Context, New, true); 3207 return New; 3208} 3209 3210// FIXME: For consistency with ActOnFields(), we should have the parser 3211// pass in the source location for the left/right braces. 3212void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3213 DeclTy **Elements, unsigned NumElements) { 3214 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3215 3216 if (Enum) { 3217 if (EnumDecl *Def = cast_or_null<EnumDecl>(Enum->getDefinition(Context))) { 3218 // Diagnose code like: 3219 // enum e0 { 3220 // E0 = sizeof(enum e0 { E1 }) 3221 // }; 3222 Diag(Def->getLocation(), diag::err_nested_redefinition) 3223 << Enum->getDeclName(); 3224 Diag(Enum->getLocation(), diag::note_previous_definition); 3225 Enum->setInvalidDecl(); 3226 return; 3227 } 3228 } 3229 // TODO: If the result value doesn't fit in an int, it must be a long or long 3230 // long value. ISO C does not support this, but GCC does as an extension, 3231 // emit a warning. 3232 unsigned IntWidth = Context.Target.getIntWidth(); 3233 3234 // Verify that all the values are okay, compute the size of the values, and 3235 // reverse the list. 3236 unsigned NumNegativeBits = 0; 3237 unsigned NumPositiveBits = 0; 3238 3239 // Keep track of whether all elements have type int. 3240 bool AllElementsInt = true; 3241 3242 QualType EnumType = Context.getTypeDeclType(Enum); 3243 EnumConstantDecl *EltList = 0; 3244 for (unsigned i = 0; i != NumElements; ++i) { 3245 EnumConstantDecl *ECD = 3246 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3247 if (!ECD) continue; // Already issued a diagnostic. 3248 3249 // If the enum value doesn't fit in an int, emit an extension warning. 3250 const llvm::APSInt &InitVal = ECD->getInitVal(); 3251 assert(InitVal.getBitWidth() >= IntWidth && 3252 "Should have promoted value to int"); 3253 if (InitVal.getBitWidth() > IntWidth) { 3254 llvm::APSInt V(InitVal); 3255 V.trunc(IntWidth); 3256 V.extend(InitVal.getBitWidth()); 3257 if (V != InitVal) 3258 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3259 << InitVal.toString(10); 3260 } 3261 3262 // Keep track of the size of positive and negative values. 3263 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3264 NumPositiveBits = std::max(NumPositiveBits, 3265 (unsigned)InitVal.getActiveBits()); 3266 else 3267 NumNegativeBits = std::max(NumNegativeBits, 3268 (unsigned)InitVal.getMinSignedBits()); 3269 3270 // Keep track of whether every enum element has type int (very commmon). 3271 if (AllElementsInt) 3272 AllElementsInt = ECD->getType() == Context.IntTy; 3273 3274 ECD->setNextDeclarator(EltList); 3275 EltList = ECD; 3276 } 3277 3278 // Figure out the type that should be used for this enum. 3279 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3280 QualType BestType; 3281 unsigned BestWidth; 3282 3283 if (NumNegativeBits) { 3284 // If there is a negative value, figure out the smallest integer type (of 3285 // int/long/longlong) that fits. 3286 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3287 BestType = Context.IntTy; 3288 BestWidth = IntWidth; 3289 } else { 3290 BestWidth = Context.Target.getLongWidth(); 3291 3292 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3293 BestType = Context.LongTy; 3294 else { 3295 BestWidth = Context.Target.getLongLongWidth(); 3296 3297 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3298 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3299 BestType = Context.LongLongTy; 3300 } 3301 } 3302 } else { 3303 // If there is no negative value, figure out which of uint, ulong, ulonglong 3304 // fits. 3305 if (NumPositiveBits <= IntWidth) { 3306 BestType = Context.UnsignedIntTy; 3307 BestWidth = IntWidth; 3308 } else if (NumPositiveBits <= 3309 (BestWidth = Context.Target.getLongWidth())) { 3310 BestType = Context.UnsignedLongTy; 3311 } else { 3312 BestWidth = Context.Target.getLongLongWidth(); 3313 assert(NumPositiveBits <= BestWidth && 3314 "How could an initializer get larger than ULL?"); 3315 BestType = Context.UnsignedLongLongTy; 3316 } 3317 } 3318 3319 // Loop over all of the enumerator constants, changing their types to match 3320 // the type of the enum if needed. 3321 for (unsigned i = 0; i != NumElements; ++i) { 3322 EnumConstantDecl *ECD = 3323 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3324 if (!ECD) continue; // Already issued a diagnostic. 3325 3326 // Standard C says the enumerators have int type, but we allow, as an 3327 // extension, the enumerators to be larger than int size. If each 3328 // enumerator value fits in an int, type it as an int, otherwise type it the 3329 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3330 // that X has type 'int', not 'unsigned'. 3331 if (ECD->getType() == Context.IntTy) { 3332 // Make sure the init value is signed. 3333 llvm::APSInt IV = ECD->getInitVal(); 3334 IV.setIsSigned(true); 3335 ECD->setInitVal(IV); 3336 3337 if (getLangOptions().CPlusPlus) 3338 // C++ [dcl.enum]p4: Following the closing brace of an 3339 // enum-specifier, each enumerator has the type of its 3340 // enumeration. 3341 ECD->setType(EnumType); 3342 continue; // Already int type. 3343 } 3344 3345 // Determine whether the value fits into an int. 3346 llvm::APSInt InitVal = ECD->getInitVal(); 3347 bool FitsInInt; 3348 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3349 FitsInInt = InitVal.getActiveBits() < IntWidth; 3350 else 3351 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3352 3353 // If it fits into an integer type, force it. Otherwise force it to match 3354 // the enum decl type. 3355 QualType NewTy; 3356 unsigned NewWidth; 3357 bool NewSign; 3358 if (FitsInInt) { 3359 NewTy = Context.IntTy; 3360 NewWidth = IntWidth; 3361 NewSign = true; 3362 } else if (ECD->getType() == BestType) { 3363 // Already the right type! 3364 if (getLangOptions().CPlusPlus) 3365 // C++ [dcl.enum]p4: Following the closing brace of an 3366 // enum-specifier, each enumerator has the type of its 3367 // enumeration. 3368 ECD->setType(EnumType); 3369 continue; 3370 } else { 3371 NewTy = BestType; 3372 NewWidth = BestWidth; 3373 NewSign = BestType->isSignedIntegerType(); 3374 } 3375 3376 // Adjust the APSInt value. 3377 InitVal.extOrTrunc(NewWidth); 3378 InitVal.setIsSigned(NewSign); 3379 ECD->setInitVal(InitVal); 3380 3381 // Adjust the Expr initializer and type. 3382 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3383 /*isLvalue=*/false)); 3384 if (getLangOptions().CPlusPlus) 3385 // C++ [dcl.enum]p4: Following the closing brace of an 3386 // enum-specifier, each enumerator has the type of its 3387 // enumeration. 3388 ECD->setType(EnumType); 3389 else 3390 ECD->setType(NewTy); 3391 } 3392 3393 Enum->completeDefinition(Context, BestType); 3394 Consumer.HandleTagDeclDefinition(Enum); 3395} 3396 3397Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3398 ExprArg expr) { 3399 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3400 3401 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3402} 3403 3404 3405void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3406 ExprTy *alignment, SourceLocation PragmaLoc, 3407 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3408 Expr *Alignment = static_cast<Expr *>(alignment); 3409 3410 // If specified then alignment must be a "small" power of two. 3411 unsigned AlignmentVal = 0; 3412 if (Alignment) { 3413 llvm::APSInt Val; 3414 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3415 !Val.isPowerOf2() || 3416 Val.getZExtValue() > 16) { 3417 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3418 delete Alignment; 3419 return; // Ignore 3420 } 3421 3422 AlignmentVal = (unsigned) Val.getZExtValue(); 3423 } 3424 3425 switch (Kind) { 3426 case Action::PPK_Default: // pack([n]) 3427 PackContext.setAlignment(AlignmentVal); 3428 break; 3429 3430 case Action::PPK_Show: // pack(show) 3431 // Show the current alignment, making sure to show the right value 3432 // for the default. 3433 AlignmentVal = PackContext.getAlignment(); 3434 // FIXME: This should come from the target. 3435 if (AlignmentVal == 0) 3436 AlignmentVal = 8; 3437 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3438 break; 3439 3440 case Action::PPK_Push: // pack(push [, id] [, [n]) 3441 PackContext.push(Name); 3442 // Set the new alignment if specified. 3443 if (Alignment) 3444 PackContext.setAlignment(AlignmentVal); 3445 break; 3446 3447 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3448 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3449 // "#pragma pack(pop, identifier, n) is undefined" 3450 if (Alignment && Name) 3451 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3452 3453 // Do the pop. 3454 if (!PackContext.pop(Name)) { 3455 // If a name was specified then failure indicates the name 3456 // wasn't found. Otherwise failure indicates the stack was 3457 // empty. 3458 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3459 << (Name ? "no record matching name" : "stack empty"); 3460 3461 // FIXME: Warn about popping named records as MSVC does. 3462 } else { 3463 // Pop succeeded, set the new alignment if specified. 3464 if (Alignment) 3465 PackContext.setAlignment(AlignmentVal); 3466 } 3467 break; 3468 3469 default: 3470 assert(0 && "Invalid #pragma pack kind."); 3471 } 3472} 3473 3474bool PragmaPackStack::pop(IdentifierInfo *Name) { 3475 if (Stack.empty()) 3476 return false; 3477 3478 // If name is empty just pop top. 3479 if (!Name) { 3480 Alignment = Stack.back().first; 3481 Stack.pop_back(); 3482 return true; 3483 } 3484 3485 // Otherwise, find the named record. 3486 for (unsigned i = Stack.size(); i != 0; ) { 3487 --i; 3488 if (Stack[i].second == Name) { 3489 // Found it, pop up to and including this record. 3490 Alignment = Stack[i].first; 3491 Stack.erase(Stack.begin() + i, Stack.end()); 3492 return true; 3493 } 3494 } 3495 3496 return false; 3497} 3498