1 //===--- Sema.cpp - AST Builder and Semantic Analysis Implementation ------===// 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 the actions class which performs semantic analysis and 11 // builds an AST out of a parse stream. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "clang/Sema/SemaInternal.h" 16 #include "clang/AST/ASTContext.h" 17 #include "clang/AST/ASTDiagnostic.h" 18 #include "clang/AST/DeclCXX.h" 19 #include "clang/AST/DeclFriend.h" 20 #include "clang/AST/DeclObjC.h" 21 #include "clang/AST/Expr.h" 22 #include "clang/AST/ExprCXX.h" 23 #include "clang/AST/StmtCXX.h" 24 #include "clang/Basic/DiagnosticOptions.h" 25 #include "clang/Basic/FileManager.h" 26 #include "clang/Basic/PartialDiagnostic.h" 27 #include "clang/Basic/TargetInfo.h" 28 #include "clang/Lex/HeaderSearch.h" 29 #include "clang/Lex/Preprocessor.h" 30 #include "clang/Sema/CXXFieldCollector.h" 31 #include "clang/Sema/DelayedDiagnostic.h" 32 #include "clang/Sema/ExternalSemaSource.h" 33 #include "clang/Sema/MultiplexExternalSemaSource.h" 34 #include "clang/Sema/ObjCMethodList.h" 35 #include "clang/Sema/PrettyDeclStackTrace.h" 36 #include "clang/Sema/Scope.h" 37 #include "clang/Sema/ScopeInfo.h" 38 #include "clang/Sema/SemaConsumer.h" 39 #include "clang/Sema/TemplateDeduction.h" 40 #include "llvm/ADT/APFloat.h" 41 #include "llvm/ADT/DenseMap.h" 42 #include "llvm/ADT/SmallSet.h" 43 #include "llvm/Support/CrashRecoveryContext.h" 44 using namespace clang; 45 using namespace sema; 46 47 SourceLocation Sema::getLocForEndOfToken(SourceLocation Loc, unsigned Offset) { 48 return Lexer::getLocForEndOfToken(Loc, Offset, SourceMgr, LangOpts); 49 } 50 51 ModuleLoader &Sema::getModuleLoader() const { return PP.getModuleLoader(); } 52 53 PrintingPolicy Sema::getPrintingPolicy(const ASTContext &Context, 54 const Preprocessor &PP) { 55 PrintingPolicy Policy = Context.getPrintingPolicy(); 56 Policy.Bool = Context.getLangOpts().Bool; 57 if (!Policy.Bool) { 58 if (const MacroInfo * 59 BoolMacro = PP.getMacroInfo(&Context.Idents.get("bool"))) { 60 Policy.Bool = BoolMacro->isObjectLike() && 61 BoolMacro->getNumTokens() == 1 && 62 BoolMacro->getReplacementToken(0).is(tok::kw__Bool); 63 } 64 } 65 66 return Policy; 67 } 68 69 void Sema::ActOnTranslationUnitScope(Scope *S) { 70 TUScope = S; 71 PushDeclContext(S, Context.getTranslationUnitDecl()); 72 } 73 74 Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer, 75 TranslationUnitKind TUKind, 76 CodeCompleteConsumer *CodeCompleter) 77 : ExternalSource(nullptr), 78 isMultiplexExternalSource(false), FPFeatures(pp.getLangOpts()), 79 LangOpts(pp.getLangOpts()), PP(pp), Context(ctxt), Consumer(consumer), 80 Diags(PP.getDiagnostics()), SourceMgr(PP.getSourceManager()), 81 CollectStats(false), CodeCompleter(CodeCompleter), 82 CurContext(nullptr), OriginalLexicalContext(nullptr), 83 PackContext(nullptr), MSStructPragmaOn(false), 84 MSPointerToMemberRepresentationMethod( 85 LangOpts.getMSPointerToMemberRepresentationMethod()), 86 VtorDispModeStack(1, MSVtorDispAttr::Mode(LangOpts.VtorDispMode)), 87 DataSegStack(nullptr), BSSSegStack(nullptr), ConstSegStack(nullptr), 88 CodeSegStack(nullptr), CurInitSeg(nullptr), VisContext(nullptr), 89 IsBuildingRecoveryCallExpr(false), 90 ExprNeedsCleanups(false), LateTemplateParser(nullptr), 91 LateTemplateParserCleanup(nullptr), 92 OpaqueParser(nullptr), IdResolver(pp), StdInitializerList(nullptr), 93 CXXTypeInfoDecl(nullptr), MSVCGuidDecl(nullptr), 94 NSNumberDecl(nullptr), 95 NSStringDecl(nullptr), StringWithUTF8StringMethod(nullptr), 96 NSArrayDecl(nullptr), ArrayWithObjectsMethod(nullptr), 97 NSDictionaryDecl(nullptr), DictionaryWithObjectsMethod(nullptr), 98 MSAsmLabelNameCounter(0), 99 GlobalNewDeleteDeclared(false), 100 TUKind(TUKind), 101 NumSFINAEErrors(0), 102 AccessCheckingSFINAE(false), InNonInstantiationSFINAEContext(false), 103 NonInstantiationEntries(0), ArgumentPackSubstitutionIndex(-1), 104 CurrentInstantiationScope(nullptr), DisableTypoCorrection(false), 105 TyposCorrected(0), AnalysisWarnings(*this), ThreadSafetyDeclCache(nullptr), 106 VarDataSharingAttributesStack(nullptr), CurScope(nullptr), 107 Ident_super(nullptr), Ident___float128(nullptr) 108 { 109 TUScope = nullptr; 110 111 LoadedExternalKnownNamespaces = false; 112 for (unsigned I = 0; I != NSAPI::NumNSNumberLiteralMethods; ++I) 113 NSNumberLiteralMethods[I] = nullptr; 114 115 if (getLangOpts().ObjC1) 116 NSAPIObj.reset(new NSAPI(Context)); 117 118 if (getLangOpts().CPlusPlus) 119 FieldCollector.reset(new CXXFieldCollector()); 120 121 // Tell diagnostics how to render things from the AST library. 122 PP.getDiagnostics().SetArgToStringFn(&FormatASTNodeDiagnosticArgument, 123 &Context); 124 125 ExprEvalContexts.emplace_back(PotentiallyEvaluated, 0, false, nullptr, false); 126 127 FunctionScopes.push_back(new FunctionScopeInfo(Diags)); 128 129 // Initilization of data sharing attributes stack for OpenMP 130 InitDataSharingAttributesStack(); 131 } 132 133 void Sema::addImplicitTypedef(StringRef Name, QualType T) { 134 DeclarationName DN = &Context.Idents.get(Name); 135 if (IdResolver.begin(DN) == IdResolver.end()) 136 PushOnScopeChains(Context.buildImplicitTypedef(T, Name), TUScope); 137 } 138 139 void Sema::Initialize() { 140 // Tell the AST consumer about this Sema object. 141 Consumer.Initialize(Context); 142 143 // FIXME: Isn't this redundant with the initialization above? 144 if (SemaConsumer *SC = dyn_cast<SemaConsumer>(&Consumer)) 145 SC->InitializeSema(*this); 146 147 // Tell the external Sema source about this Sema object. 148 if (ExternalSemaSource *ExternalSema 149 = dyn_cast_or_null<ExternalSemaSource>(Context.getExternalSource())) 150 ExternalSema->InitializeSema(*this); 151 152 // This needs to happen after ExternalSemaSource::InitializeSema(this) or we 153 // will not be able to merge any duplicate __va_list_tag decls correctly. 154 VAListTagName = PP.getIdentifierInfo("__va_list_tag"); 155 156 // Initialize predefined 128-bit integer types, if needed. 157 if (Context.getTargetInfo().hasInt128Type()) { 158 // If either of the 128-bit integer types are unavailable to name lookup, 159 // define them now. 160 DeclarationName Int128 = &Context.Idents.get("__int128_t"); 161 if (IdResolver.begin(Int128) == IdResolver.end()) 162 PushOnScopeChains(Context.getInt128Decl(), TUScope); 163 164 DeclarationName UInt128 = &Context.Idents.get("__uint128_t"); 165 if (IdResolver.begin(UInt128) == IdResolver.end()) 166 PushOnScopeChains(Context.getUInt128Decl(), TUScope); 167 } 168 169 170 // Initialize predefined Objective-C types: 171 if (PP.getLangOpts().ObjC1) { 172 // If 'SEL' does not yet refer to any declarations, make it refer to the 173 // predefined 'SEL'. 174 DeclarationName SEL = &Context.Idents.get("SEL"); 175 if (IdResolver.begin(SEL) == IdResolver.end()) 176 PushOnScopeChains(Context.getObjCSelDecl(), TUScope); 177 178 // If 'id' does not yet refer to any declarations, make it refer to the 179 // predefined 'id'. 180 DeclarationName Id = &Context.Idents.get("id"); 181 if (IdResolver.begin(Id) == IdResolver.end()) 182 PushOnScopeChains(Context.getObjCIdDecl(), TUScope); 183 184 // Create the built-in typedef for 'Class'. 185 DeclarationName Class = &Context.Idents.get("Class"); 186 if (IdResolver.begin(Class) == IdResolver.end()) 187 PushOnScopeChains(Context.getObjCClassDecl(), TUScope); 188 189 // Create the built-in forward declaratino for 'Protocol'. 190 DeclarationName Protocol = &Context.Idents.get("Protocol"); 191 if (IdResolver.begin(Protocol) == IdResolver.end()) 192 PushOnScopeChains(Context.getObjCProtocolDecl(), TUScope); 193 } 194 195 // Initialize Microsoft "predefined C++ types". 196 if (PP.getLangOpts().MSVCCompat) { 197 if (PP.getLangOpts().CPlusPlus && 198 IdResolver.begin(&Context.Idents.get("type_info")) == IdResolver.end()) 199 PushOnScopeChains(Context.buildImplicitRecord("type_info", TTK_Class), 200 TUScope); 201 202 addImplicitTypedef("size_t", Context.getSizeType()); 203 } 204 205 // Initialize predefined OpenCL types. 206 if (PP.getLangOpts().OpenCL) { 207 addImplicitTypedef("image1d_t", Context.OCLImage1dTy); 208 addImplicitTypedef("image1d_array_t", Context.OCLImage1dArrayTy); 209 addImplicitTypedef("image1d_buffer_t", Context.OCLImage1dBufferTy); 210 addImplicitTypedef("image2d_t", Context.OCLImage2dTy); 211 addImplicitTypedef("image2d_array_t", Context.OCLImage2dArrayTy); 212 addImplicitTypedef("image3d_t", Context.OCLImage3dTy); 213 addImplicitTypedef("sampler_t", Context.OCLSamplerTy); 214 addImplicitTypedef("event_t", Context.OCLEventTy); 215 if (getLangOpts().OpenCLVersion >= 200) { 216 addImplicitTypedef("atomic_int", Context.getAtomicType(Context.IntTy)); 217 addImplicitTypedef("atomic_uint", 218 Context.getAtomicType(Context.UnsignedIntTy)); 219 addImplicitTypedef("atomic_long", Context.getAtomicType(Context.LongTy)); 220 addImplicitTypedef("atomic_ulong", 221 Context.getAtomicType(Context.UnsignedLongTy)); 222 addImplicitTypedef("atomic_float", 223 Context.getAtomicType(Context.FloatTy)); 224 addImplicitTypedef("atomic_double", 225 Context.getAtomicType(Context.DoubleTy)); 226 // OpenCLC v2.0, s6.13.11.6 requires that atomic_flag is implemented as 227 // 32-bit integer and OpenCLC v2.0, s6.1.1 int is always 32-bit wide. 228 addImplicitTypedef("atomic_flag", Context.getAtomicType(Context.IntTy)); 229 addImplicitTypedef("atomic_intptr_t", 230 Context.getAtomicType(Context.getIntPtrType())); 231 addImplicitTypedef("atomic_uintptr_t", 232 Context.getAtomicType(Context.getUIntPtrType())); 233 addImplicitTypedef("atomic_size_t", 234 Context.getAtomicType(Context.getSizeType())); 235 addImplicitTypedef("atomic_ptrdiff_t", 236 Context.getAtomicType(Context.getPointerDiffType())); 237 } 238 } 239 240 DeclarationName BuiltinVaList = &Context.Idents.get("__builtin_va_list"); 241 if (IdResolver.begin(BuiltinVaList) == IdResolver.end()) 242 PushOnScopeChains(Context.getBuiltinVaListDecl(), TUScope); 243 } 244 245 Sema::~Sema() { 246 llvm::DeleteContainerSeconds(LateParsedTemplateMap); 247 if (PackContext) FreePackedContext(); 248 if (VisContext) FreeVisContext(); 249 // Kill all the active scopes. 250 for (unsigned I = 1, E = FunctionScopes.size(); I != E; ++I) 251 delete FunctionScopes[I]; 252 if (FunctionScopes.size() == 1) 253 delete FunctionScopes[0]; 254 255 // Tell the SemaConsumer to forget about us; we're going out of scope. 256 if (SemaConsumer *SC = dyn_cast<SemaConsumer>(&Consumer)) 257 SC->ForgetSema(); 258 259 // Detach from the external Sema source. 260 if (ExternalSemaSource *ExternalSema 261 = dyn_cast_or_null<ExternalSemaSource>(Context.getExternalSource())) 262 ExternalSema->ForgetSema(); 263 264 // If Sema's ExternalSource is the multiplexer - we own it. 265 if (isMultiplexExternalSource) 266 delete ExternalSource; 267 268 threadSafety::threadSafetyCleanup(ThreadSafetyDeclCache); 269 270 // Destroys data sharing attributes stack for OpenMP 271 DestroyDataSharingAttributesStack(); 272 273 assert(DelayedTypos.empty() && "Uncorrected typos!"); 274 } 275 276 /// makeUnavailableInSystemHeader - There is an error in the current 277 /// context. If we're still in a system header, and we can plausibly 278 /// make the relevant declaration unavailable instead of erroring, do 279 /// so and return true. 280 bool Sema::makeUnavailableInSystemHeader(SourceLocation loc, 281 StringRef msg) { 282 // If we're not in a function, it's an error. 283 FunctionDecl *fn = dyn_cast<FunctionDecl>(CurContext); 284 if (!fn) return false; 285 286 // If we're in template instantiation, it's an error. 287 if (!ActiveTemplateInstantiations.empty()) 288 return false; 289 290 // If that function's not in a system header, it's an error. 291 if (!Context.getSourceManager().isInSystemHeader(loc)) 292 return false; 293 294 // If the function is already unavailable, it's not an error. 295 if (fn->hasAttr<UnavailableAttr>()) return true; 296 297 fn->addAttr(UnavailableAttr::CreateImplicit(Context, msg, loc)); 298 return true; 299 } 300 301 ASTMutationListener *Sema::getASTMutationListener() const { 302 return getASTConsumer().GetASTMutationListener(); 303 } 304 305 ///\brief Registers an external source. If an external source already exists, 306 /// creates a multiplex external source and appends to it. 307 /// 308 ///\param[in] E - A non-null external sema source. 309 /// 310 void Sema::addExternalSource(ExternalSemaSource *E) { 311 assert(E && "Cannot use with NULL ptr"); 312 313 if (!ExternalSource) { 314 ExternalSource = E; 315 return; 316 } 317 318 if (isMultiplexExternalSource) 319 static_cast<MultiplexExternalSemaSource*>(ExternalSource)->addSource(*E); 320 else { 321 ExternalSource = new MultiplexExternalSemaSource(*ExternalSource, *E); 322 isMultiplexExternalSource = true; 323 } 324 } 325 326 /// \brief Print out statistics about the semantic analysis. 327 void Sema::PrintStats() const { 328 llvm::errs() << "\n*** Semantic Analysis Stats:\n"; 329 llvm::errs() << NumSFINAEErrors << " SFINAE diagnostics trapped.\n"; 330 331 BumpAlloc.PrintStats(); 332 AnalysisWarnings.PrintStats(); 333 } 334 335 /// ImpCastExprToType - If Expr is not of type 'Type', insert an implicit cast. 336 /// If there is already an implicit cast, merge into the existing one. 337 /// The result is of the given category. 338 ExprResult Sema::ImpCastExprToType(Expr *E, QualType Ty, 339 CastKind Kind, ExprValueKind VK, 340 const CXXCastPath *BasePath, 341 CheckedConversionKind CCK) { 342 #ifndef NDEBUG 343 if (VK == VK_RValue && !E->isRValue()) { 344 switch (Kind) { 345 default: 346 llvm_unreachable("can't implicitly cast lvalue to rvalue with this cast " 347 "kind"); 348 case CK_LValueToRValue: 349 case CK_ArrayToPointerDecay: 350 case CK_FunctionToPointerDecay: 351 case CK_ToVoid: 352 break; 353 } 354 } 355 assert((VK == VK_RValue || !E->isRValue()) && "can't cast rvalue to lvalue"); 356 #endif 357 358 QualType ExprTy = Context.getCanonicalType(E->getType()); 359 QualType TypeTy = Context.getCanonicalType(Ty); 360 361 if (ExprTy == TypeTy) 362 return E; 363 364 if (ImplicitCastExpr *ImpCast = dyn_cast<ImplicitCastExpr>(E)) { 365 if (ImpCast->getCastKind() == Kind && (!BasePath || BasePath->empty())) { 366 ImpCast->setType(Ty); 367 ImpCast->setValueKind(VK); 368 return E; 369 } 370 } 371 372 return ImplicitCastExpr::Create(Context, Ty, Kind, E, BasePath, VK); 373 } 374 375 /// ScalarTypeToBooleanCastKind - Returns the cast kind corresponding 376 /// to the conversion from scalar type ScalarTy to the Boolean type. 377 CastKind Sema::ScalarTypeToBooleanCastKind(QualType ScalarTy) { 378 switch (ScalarTy->getScalarTypeKind()) { 379 case Type::STK_Bool: return CK_NoOp; 380 case Type::STK_CPointer: return CK_PointerToBoolean; 381 case Type::STK_BlockPointer: return CK_PointerToBoolean; 382 case Type::STK_ObjCObjectPointer: return CK_PointerToBoolean; 383 case Type::STK_MemberPointer: return CK_MemberPointerToBoolean; 384 case Type::STK_Integral: return CK_IntegralToBoolean; 385 case Type::STK_Floating: return CK_FloatingToBoolean; 386 case Type::STK_IntegralComplex: return CK_IntegralComplexToBoolean; 387 case Type::STK_FloatingComplex: return CK_FloatingComplexToBoolean; 388 } 389 return CK_Invalid; 390 } 391 392 /// \brief Used to prune the decls of Sema's UnusedFileScopedDecls vector. 393 static bool ShouldRemoveFromUnused(Sema *SemaRef, const DeclaratorDecl *D) { 394 if (D->getMostRecentDecl()->isUsed()) 395 return true; 396 397 if (D->isExternallyVisible()) 398 return true; 399 400 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 401 // UnusedFileScopedDecls stores the first declaration. 402 // The declaration may have become definition so check again. 403 const FunctionDecl *DeclToCheck; 404 if (FD->hasBody(DeclToCheck)) 405 return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); 406 407 // Later redecls may add new information resulting in not having to warn, 408 // so check again. 409 DeclToCheck = FD->getMostRecentDecl(); 410 if (DeclToCheck != FD) 411 return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); 412 } 413 414 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 415 // If a variable usable in constant expressions is referenced, 416 // don't warn if it isn't used: if the value of a variable is required 417 // for the computation of a constant expression, it doesn't make sense to 418 // warn even if the variable isn't odr-used. (isReferenced doesn't 419 // precisely reflect that, but it's a decent approximation.) 420 if (VD->isReferenced() && 421 VD->isUsableInConstantExpressions(SemaRef->Context)) 422 return true; 423 424 // UnusedFileScopedDecls stores the first declaration. 425 // The declaration may have become definition so check again. 426 const VarDecl *DeclToCheck = VD->getDefinition(); 427 if (DeclToCheck) 428 return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); 429 430 // Later redecls may add new information resulting in not having to warn, 431 // so check again. 432 DeclToCheck = VD->getMostRecentDecl(); 433 if (DeclToCheck != VD) 434 return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); 435 } 436 437 return false; 438 } 439 440 /// Obtains a sorted list of functions that are undefined but ODR-used. 441 void Sema::getUndefinedButUsed( 442 SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> > &Undefined) { 443 for (llvm::DenseMap<NamedDecl *, SourceLocation>::iterator 444 I = UndefinedButUsed.begin(), E = UndefinedButUsed.end(); 445 I != E; ++I) { 446 NamedDecl *ND = I->first; 447 448 // Ignore attributes that have become invalid. 449 if (ND->isInvalidDecl()) continue; 450 451 // __attribute__((weakref)) is basically a definition. 452 if (ND->hasAttr<WeakRefAttr>()) continue; 453 454 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) { 455 if (FD->isDefined()) 456 continue; 457 if (FD->isExternallyVisible() && 458 !FD->getMostRecentDecl()->isInlined()) 459 continue; 460 } else { 461 if (cast<VarDecl>(ND)->hasDefinition() != VarDecl::DeclarationOnly) 462 continue; 463 if (ND->isExternallyVisible()) 464 continue; 465 } 466 467 Undefined.push_back(std::make_pair(ND, I->second)); 468 } 469 470 // Sort (in order of use site) so that we're not dependent on the iteration 471 // order through an llvm::DenseMap. 472 SourceManager &SM = Context.getSourceManager(); 473 std::sort(Undefined.begin(), Undefined.end(), 474 [&SM](const std::pair<NamedDecl *, SourceLocation> &l, 475 const std::pair<NamedDecl *, SourceLocation> &r) { 476 if (l.second.isValid() && !r.second.isValid()) 477 return true; 478 if (!l.second.isValid() && r.second.isValid()) 479 return false; 480 if (l.second != r.second) 481 return SM.isBeforeInTranslationUnit(l.second, r.second); 482 return SM.isBeforeInTranslationUnit(l.first->getLocation(), 483 r.first->getLocation()); 484 }); 485 } 486 487 /// checkUndefinedButUsed - Check for undefined objects with internal linkage 488 /// or that are inline. 489 static void checkUndefinedButUsed(Sema &S) { 490 if (S.UndefinedButUsed.empty()) return; 491 492 // Collect all the still-undefined entities with internal linkage. 493 SmallVector<std::pair<NamedDecl *, SourceLocation>, 16> Undefined; 494 S.getUndefinedButUsed(Undefined); 495 if (Undefined.empty()) return; 496 497 for (SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> >::iterator 498 I = Undefined.begin(), E = Undefined.end(); I != E; ++I) { 499 NamedDecl *ND = I->first; 500 501 if (ND->hasAttr<DLLImportAttr>() || ND->hasAttr<DLLExportAttr>()) { 502 // An exported function will always be emitted when defined, so even if 503 // the function is inline, it doesn't have to be emitted in this TU. An 504 // imported function implies that it has been exported somewhere else. 505 continue; 506 } 507 508 if (!ND->isExternallyVisible()) { 509 S.Diag(ND->getLocation(), diag::warn_undefined_internal) 510 << isa<VarDecl>(ND) << ND; 511 } else { 512 assert(cast<FunctionDecl>(ND)->getMostRecentDecl()->isInlined() && 513 "used object requires definition but isn't inline or internal?"); 514 S.Diag(ND->getLocation(), diag::warn_undefined_inline) << ND; 515 } 516 if (I->second.isValid()) 517 S.Diag(I->second, diag::note_used_here); 518 } 519 } 520 521 void Sema::LoadExternalWeakUndeclaredIdentifiers() { 522 if (!ExternalSource) 523 return; 524 525 SmallVector<std::pair<IdentifierInfo *, WeakInfo>, 4> WeakIDs; 526 ExternalSource->ReadWeakUndeclaredIdentifiers(WeakIDs); 527 for (auto &WeakID : WeakIDs) 528 WeakUndeclaredIdentifiers.insert(WeakID); 529 } 530 531 532 typedef llvm::DenseMap<const CXXRecordDecl*, bool> RecordCompleteMap; 533 534 /// \brief Returns true, if all methods and nested classes of the given 535 /// CXXRecordDecl are defined in this translation unit. 536 /// 537 /// Should only be called from ActOnEndOfTranslationUnit so that all 538 /// definitions are actually read. 539 static bool MethodsAndNestedClassesComplete(const CXXRecordDecl *RD, 540 RecordCompleteMap &MNCComplete) { 541 RecordCompleteMap::iterator Cache = MNCComplete.find(RD); 542 if (Cache != MNCComplete.end()) 543 return Cache->second; 544 if (!RD->isCompleteDefinition()) 545 return false; 546 bool Complete = true; 547 for (DeclContext::decl_iterator I = RD->decls_begin(), 548 E = RD->decls_end(); 549 I != E && Complete; ++I) { 550 if (const CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(*I)) 551 Complete = M->isDefined() || (M->isPure() && !isa<CXXDestructorDecl>(M)); 552 else if (const FunctionTemplateDecl *F = dyn_cast<FunctionTemplateDecl>(*I)) 553 // If the template function is marked as late template parsed at this point, 554 // it has not been instantiated and therefore we have not performed semantic 555 // analysis on it yet, so we cannot know if the type can be considered 556 // complete. 557 Complete = !F->getTemplatedDecl()->isLateTemplateParsed() && 558 F->getTemplatedDecl()->isDefined(); 559 else if (const CXXRecordDecl *R = dyn_cast<CXXRecordDecl>(*I)) { 560 if (R->isInjectedClassName()) 561 continue; 562 if (R->hasDefinition()) 563 Complete = MethodsAndNestedClassesComplete(R->getDefinition(), 564 MNCComplete); 565 else 566 Complete = false; 567 } 568 } 569 MNCComplete[RD] = Complete; 570 return Complete; 571 } 572 573 /// \brief Returns true, if the given CXXRecordDecl is fully defined in this 574 /// translation unit, i.e. all methods are defined or pure virtual and all 575 /// friends, friend functions and nested classes are fully defined in this 576 /// translation unit. 577 /// 578 /// Should only be called from ActOnEndOfTranslationUnit so that all 579 /// definitions are actually read. 580 static bool IsRecordFullyDefined(const CXXRecordDecl *RD, 581 RecordCompleteMap &RecordsComplete, 582 RecordCompleteMap &MNCComplete) { 583 RecordCompleteMap::iterator Cache = RecordsComplete.find(RD); 584 if (Cache != RecordsComplete.end()) 585 return Cache->second; 586 bool Complete = MethodsAndNestedClassesComplete(RD, MNCComplete); 587 for (CXXRecordDecl::friend_iterator I = RD->friend_begin(), 588 E = RD->friend_end(); 589 I != E && Complete; ++I) { 590 // Check if friend classes and methods are complete. 591 if (TypeSourceInfo *TSI = (*I)->getFriendType()) { 592 // Friend classes are available as the TypeSourceInfo of the FriendDecl. 593 if (CXXRecordDecl *FriendD = TSI->getType()->getAsCXXRecordDecl()) 594 Complete = MethodsAndNestedClassesComplete(FriendD, MNCComplete); 595 else 596 Complete = false; 597 } else { 598 // Friend functions are available through the NamedDecl of FriendDecl. 599 if (const FunctionDecl *FD = 600 dyn_cast<FunctionDecl>((*I)->getFriendDecl())) 601 Complete = FD->isDefined(); 602 else 603 // This is a template friend, give up. 604 Complete = false; 605 } 606 } 607 RecordsComplete[RD] = Complete; 608 return Complete; 609 } 610 611 void Sema::emitAndClearUnusedLocalTypedefWarnings() { 612 if (ExternalSource) 613 ExternalSource->ReadUnusedLocalTypedefNameCandidates( 614 UnusedLocalTypedefNameCandidates); 615 for (const TypedefNameDecl *TD : UnusedLocalTypedefNameCandidates) { 616 if (TD->isReferenced()) 617 continue; 618 Diag(TD->getLocation(), diag::warn_unused_local_typedef) 619 << isa<TypeAliasDecl>(TD) << TD->getDeclName(); 620 } 621 UnusedLocalTypedefNameCandidates.clear(); 622 } 623 624 /// ActOnEndOfTranslationUnit - This is called at the very end of the 625 /// translation unit when EOF is reached and all but the top-level scope is 626 /// popped. 627 void Sema::ActOnEndOfTranslationUnit() { 628 assert(DelayedDiagnostics.getCurrentPool() == nullptr 629 && "reached end of translation unit with a pool attached?"); 630 631 // If code completion is enabled, don't perform any end-of-translation-unit 632 // work. 633 if (PP.isCodeCompletionEnabled()) 634 return; 635 636 // Complete translation units and modules define vtables and perform implicit 637 // instantiations. PCH files do not. 638 if (TUKind != TU_Prefix) { 639 DiagnoseUseOfUnimplementedSelectors(); 640 641 // If DefinedUsedVTables ends up marking any virtual member functions it 642 // might lead to more pending template instantiations, which we then need 643 // to instantiate. 644 DefineUsedVTables(); 645 646 // C++: Perform implicit template instantiations. 647 // 648 // FIXME: When we perform these implicit instantiations, we do not 649 // carefully keep track of the point of instantiation (C++ [temp.point]). 650 // This means that name lookup that occurs within the template 651 // instantiation will always happen at the end of the translation unit, 652 // so it will find some names that are not required to be found. This is 653 // valid, but we could do better by diagnosing if an instantiation uses a 654 // name that was not visible at its first point of instantiation. 655 if (ExternalSource) { 656 // Load pending instantiations from the external source. 657 SmallVector<PendingImplicitInstantiation, 4> Pending; 658 ExternalSource->ReadPendingInstantiations(Pending); 659 PendingInstantiations.insert(PendingInstantiations.begin(), 660 Pending.begin(), Pending.end()); 661 } 662 PerformPendingInstantiations(); 663 664 if (LateTemplateParserCleanup) 665 LateTemplateParserCleanup(OpaqueParser); 666 667 CheckDelayedMemberExceptionSpecs(); 668 } 669 670 // All delayed member exception specs should be checked or we end up accepting 671 // incompatible declarations. 672 // FIXME: This is wrong for TUKind == TU_Prefix. In that case, we need to 673 // write out the lists to the AST file (if any). 674 assert(DelayedDefaultedMemberExceptionSpecs.empty()); 675 assert(DelayedExceptionSpecChecks.empty()); 676 677 // Remove file scoped decls that turned out to be used. 678 UnusedFileScopedDecls.erase( 679 std::remove_if(UnusedFileScopedDecls.begin(nullptr, true), 680 UnusedFileScopedDecls.end(), 681 std::bind1st(std::ptr_fun(ShouldRemoveFromUnused), this)), 682 UnusedFileScopedDecls.end()); 683 684 if (TUKind == TU_Prefix) { 685 // Translation unit prefixes don't need any of the checking below. 686 TUScope = nullptr; 687 return; 688 } 689 690 // Check for #pragma weak identifiers that were never declared 691 LoadExternalWeakUndeclaredIdentifiers(); 692 for (auto WeakID : WeakUndeclaredIdentifiers) { 693 if (WeakID.second.getUsed()) 694 continue; 695 696 Diag(WeakID.second.getLocation(), diag::warn_weak_identifier_undeclared) 697 << WeakID.first; 698 } 699 700 if (LangOpts.CPlusPlus11 && 701 !Diags.isIgnored(diag::warn_delegating_ctor_cycle, SourceLocation())) 702 CheckDelegatingCtorCycles(); 703 704 if (TUKind == TU_Module) { 705 // If we are building a module, resolve all of the exported declarations 706 // now. 707 if (Module *CurrentModule = PP.getCurrentModule()) { 708 ModuleMap &ModMap = PP.getHeaderSearchInfo().getModuleMap(); 709 710 SmallVector<Module *, 2> Stack; 711 Stack.push_back(CurrentModule); 712 while (!Stack.empty()) { 713 Module *Mod = Stack.pop_back_val(); 714 715 // Resolve the exported declarations and conflicts. 716 // FIXME: Actually complain, once we figure out how to teach the 717 // diagnostic client to deal with complaints in the module map at this 718 // point. 719 ModMap.resolveExports(Mod, /*Complain=*/false); 720 ModMap.resolveUses(Mod, /*Complain=*/false); 721 ModMap.resolveConflicts(Mod, /*Complain=*/false); 722 723 // Queue the submodules, so their exports will also be resolved. 724 for (Module::submodule_iterator Sub = Mod->submodule_begin(), 725 SubEnd = Mod->submodule_end(); 726 Sub != SubEnd; ++Sub) { 727 Stack.push_back(*Sub); 728 } 729 } 730 } 731 732 // Warnings emitted in ActOnEndOfTranslationUnit() should be emitted for 733 // modules when they are built, not every time they are used. 734 emitAndClearUnusedLocalTypedefWarnings(); 735 736 // Modules don't need any of the checking below. 737 TUScope = nullptr; 738 return; 739 } 740 741 // C99 6.9.2p2: 742 // A declaration of an identifier for an object that has file 743 // scope without an initializer, and without a storage-class 744 // specifier or with the storage-class specifier static, 745 // constitutes a tentative definition. If a translation unit 746 // contains one or more tentative definitions for an identifier, 747 // and the translation unit contains no external definition for 748 // that identifier, then the behavior is exactly as if the 749 // translation unit contains a file scope declaration of that 750 // identifier, with the composite type as of the end of the 751 // translation unit, with an initializer equal to 0. 752 llvm::SmallSet<VarDecl *, 32> Seen; 753 for (TentativeDefinitionsType::iterator 754 T = TentativeDefinitions.begin(ExternalSource), 755 TEnd = TentativeDefinitions.end(); 756 T != TEnd; ++T) 757 { 758 VarDecl *VD = (*T)->getActingDefinition(); 759 760 // If the tentative definition was completed, getActingDefinition() returns 761 // null. If we've already seen this variable before, insert()'s second 762 // return value is false. 763 if (!VD || VD->isInvalidDecl() || !Seen.insert(VD).second) 764 continue; 765 766 if (const IncompleteArrayType *ArrayT 767 = Context.getAsIncompleteArrayType(VD->getType())) { 768 // Set the length of the array to 1 (C99 6.9.2p5). 769 Diag(VD->getLocation(), diag::warn_tentative_incomplete_array); 770 llvm::APInt One(Context.getTypeSize(Context.getSizeType()), true); 771 QualType T = Context.getConstantArrayType(ArrayT->getElementType(), 772 One, ArrayType::Normal, 0); 773 VD->setType(T); 774 } else if (RequireCompleteType(VD->getLocation(), VD->getType(), 775 diag::err_tentative_def_incomplete_type)) 776 VD->setInvalidDecl(); 777 778 CheckCompleteVariableDeclaration(VD); 779 780 // Notify the consumer that we've completed a tentative definition. 781 if (!VD->isInvalidDecl()) 782 Consumer.CompleteTentativeDefinition(VD); 783 784 } 785 786 // If there were errors, disable 'unused' warnings since they will mostly be 787 // noise. 788 if (!Diags.hasErrorOccurred()) { 789 // Output warning for unused file scoped decls. 790 for (UnusedFileScopedDeclsType::iterator 791 I = UnusedFileScopedDecls.begin(ExternalSource), 792 E = UnusedFileScopedDecls.end(); I != E; ++I) { 793 if (ShouldRemoveFromUnused(this, *I)) 794 continue; 795 796 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 797 const FunctionDecl *DiagD; 798 if (!FD->hasBody(DiagD)) 799 DiagD = FD; 800 if (DiagD->isDeleted()) 801 continue; // Deleted functions are supposed to be unused. 802 if (DiagD->isReferenced()) { 803 if (isa<CXXMethodDecl>(DiagD)) 804 Diag(DiagD->getLocation(), diag::warn_unneeded_member_function) 805 << DiagD->getDeclName(); 806 else { 807 if (FD->getStorageClass() == SC_Static && 808 !FD->isInlineSpecified() && 809 !SourceMgr.isInMainFile( 810 SourceMgr.getExpansionLoc(FD->getLocation()))) 811 Diag(DiagD->getLocation(), 812 diag::warn_unneeded_static_internal_decl) 813 << DiagD->getDeclName(); 814 else 815 Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl) 816 << /*function*/0 << DiagD->getDeclName(); 817 } 818 } else { 819 Diag(DiagD->getLocation(), 820 isa<CXXMethodDecl>(DiagD) ? diag::warn_unused_member_function 821 : diag::warn_unused_function) 822 << DiagD->getDeclName(); 823 } 824 } else { 825 const VarDecl *DiagD = cast<VarDecl>(*I)->getDefinition(); 826 if (!DiagD) 827 DiagD = cast<VarDecl>(*I); 828 if (DiagD->isReferenced()) { 829 Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl) 830 << /*variable*/1 << DiagD->getDeclName(); 831 } else if (DiagD->getType().isConstQualified()) { 832 Diag(DiagD->getLocation(), diag::warn_unused_const_variable) 833 << DiagD->getDeclName(); 834 } else { 835 Diag(DiagD->getLocation(), diag::warn_unused_variable) 836 << DiagD->getDeclName(); 837 } 838 } 839 } 840 841 if (ExternalSource) 842 ExternalSource->ReadUndefinedButUsed(UndefinedButUsed); 843 checkUndefinedButUsed(*this); 844 845 emitAndClearUnusedLocalTypedefWarnings(); 846 } 847 848 if (!Diags.isIgnored(diag::warn_unused_private_field, SourceLocation())) { 849 RecordCompleteMap RecordsComplete; 850 RecordCompleteMap MNCComplete; 851 for (NamedDeclSetType::iterator I = UnusedPrivateFields.begin(), 852 E = UnusedPrivateFields.end(); I != E; ++I) { 853 const NamedDecl *D = *I; 854 const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext()); 855 if (RD && !RD->isUnion() && 856 IsRecordFullyDefined(RD, RecordsComplete, MNCComplete)) { 857 Diag(D->getLocation(), diag::warn_unused_private_field) 858 << D->getDeclName(); 859 } 860 } 861 } 862 863 // Check we've noticed that we're no longer parsing the initializer for every 864 // variable. If we miss cases, then at best we have a performance issue and 865 // at worst a rejects-valid bug. 866 assert(ParsingInitForAutoVars.empty() && 867 "Didn't unmark var as having its initializer parsed"); 868 869 TUScope = nullptr; 870 } 871 872 873 //===----------------------------------------------------------------------===// 874 // Helper functions. 875 //===----------------------------------------------------------------------===// 876 877 DeclContext *Sema::getFunctionLevelDeclContext() { 878 DeclContext *DC = CurContext; 879 880 while (true) { 881 if (isa<BlockDecl>(DC) || isa<EnumDecl>(DC) || isa<CapturedDecl>(DC)) { 882 DC = DC->getParent(); 883 } else if (isa<CXXMethodDecl>(DC) && 884 cast<CXXMethodDecl>(DC)->getOverloadedOperator() == OO_Call && 885 cast<CXXRecordDecl>(DC->getParent())->isLambda()) { 886 DC = DC->getParent()->getParent(); 887 } 888 else break; 889 } 890 891 return DC; 892 } 893 894 /// getCurFunctionDecl - If inside of a function body, this returns a pointer 895 /// to the function decl for the function being parsed. If we're currently 896 /// in a 'block', this returns the containing context. 897 FunctionDecl *Sema::getCurFunctionDecl() { 898 DeclContext *DC = getFunctionLevelDeclContext(); 899 return dyn_cast<FunctionDecl>(DC); 900 } 901 902 ObjCMethodDecl *Sema::getCurMethodDecl() { 903 DeclContext *DC = getFunctionLevelDeclContext(); 904 while (isa<RecordDecl>(DC)) 905 DC = DC->getParent(); 906 return dyn_cast<ObjCMethodDecl>(DC); 907 } 908 909 NamedDecl *Sema::getCurFunctionOrMethodDecl() { 910 DeclContext *DC = getFunctionLevelDeclContext(); 911 if (isa<ObjCMethodDecl>(DC) || isa<FunctionDecl>(DC)) 912 return cast<NamedDecl>(DC); 913 return nullptr; 914 } 915 916 void Sema::EmitCurrentDiagnostic(unsigned DiagID) { 917 // FIXME: It doesn't make sense to me that DiagID is an incoming argument here 918 // and yet we also use the current diag ID on the DiagnosticsEngine. This has 919 // been made more painfully obvious by the refactor that introduced this 920 // function, but it is possible that the incoming argument can be 921 // eliminnated. If it truly cannot be (for example, there is some reentrancy 922 // issue I am not seeing yet), then there should at least be a clarifying 923 // comment somewhere. 924 if (Optional<TemplateDeductionInfo*> Info = isSFINAEContext()) { 925 switch (DiagnosticIDs::getDiagnosticSFINAEResponse( 926 Diags.getCurrentDiagID())) { 927 case DiagnosticIDs::SFINAE_Report: 928 // We'll report the diagnostic below. 929 break; 930 931 case DiagnosticIDs::SFINAE_SubstitutionFailure: 932 // Count this failure so that we know that template argument deduction 933 // has failed. 934 ++NumSFINAEErrors; 935 936 // Make a copy of this suppressed diagnostic and store it with the 937 // template-deduction information. 938 if (*Info && !(*Info)->hasSFINAEDiagnostic()) { 939 Diagnostic DiagInfo(&Diags); 940 (*Info)->addSFINAEDiagnostic(DiagInfo.getLocation(), 941 PartialDiagnostic(DiagInfo, Context.getDiagAllocator())); 942 } 943 944 Diags.setLastDiagnosticIgnored(); 945 Diags.Clear(); 946 return; 947 948 case DiagnosticIDs::SFINAE_AccessControl: { 949 // Per C++ Core Issue 1170, access control is part of SFINAE. 950 // Additionally, the AccessCheckingSFINAE flag can be used to temporarily 951 // make access control a part of SFINAE for the purposes of checking 952 // type traits. 953 if (!AccessCheckingSFINAE && !getLangOpts().CPlusPlus11) 954 break; 955 956 SourceLocation Loc = Diags.getCurrentDiagLoc(); 957 958 // Suppress this diagnostic. 959 ++NumSFINAEErrors; 960 961 // Make a copy of this suppressed diagnostic and store it with the 962 // template-deduction information. 963 if (*Info && !(*Info)->hasSFINAEDiagnostic()) { 964 Diagnostic DiagInfo(&Diags); 965 (*Info)->addSFINAEDiagnostic(DiagInfo.getLocation(), 966 PartialDiagnostic(DiagInfo, Context.getDiagAllocator())); 967 } 968 969 Diags.setLastDiagnosticIgnored(); 970 Diags.Clear(); 971 972 // Now the diagnostic state is clear, produce a C++98 compatibility 973 // warning. 974 Diag(Loc, diag::warn_cxx98_compat_sfinae_access_control); 975 976 // The last diagnostic which Sema produced was ignored. Suppress any 977 // notes attached to it. 978 Diags.setLastDiagnosticIgnored(); 979 return; 980 } 981 982 case DiagnosticIDs::SFINAE_Suppress: 983 // Make a copy of this suppressed diagnostic and store it with the 984 // template-deduction information; 985 if (*Info) { 986 Diagnostic DiagInfo(&Diags); 987 (*Info)->addSuppressedDiagnostic(DiagInfo.getLocation(), 988 PartialDiagnostic(DiagInfo, Context.getDiagAllocator())); 989 } 990 991 // Suppress this diagnostic. 992 Diags.setLastDiagnosticIgnored(); 993 Diags.Clear(); 994 return; 995 } 996 } 997 998 // Set up the context's printing policy based on our current state. 999 Context.setPrintingPolicy(getPrintingPolicy()); 1000 1001 // Emit the diagnostic. 1002 if (!Diags.EmitCurrentDiagnostic()) 1003 return; 1004 1005 // If this is not a note, and we're in a template instantiation 1006 // that is different from the last template instantiation where 1007 // we emitted an error, print a template instantiation 1008 // backtrace. 1009 if (!DiagnosticIDs::isBuiltinNote(DiagID) && 1010 !ActiveTemplateInstantiations.empty() && 1011 ActiveTemplateInstantiations.back() 1012 != LastTemplateInstantiationErrorContext) { 1013 PrintInstantiationStack(); 1014 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiations.back(); 1015 } 1016 } 1017 1018 Sema::SemaDiagnosticBuilder 1019 Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) { 1020 SemaDiagnosticBuilder Builder(Diag(Loc, PD.getDiagID())); 1021 PD.Emit(Builder); 1022 1023 return Builder; 1024 } 1025 1026 /// \brief Looks through the macro-expansion chain for the given 1027 /// location, looking for a macro expansion with the given name. 1028 /// If one is found, returns true and sets the location to that 1029 /// expansion loc. 1030 bool Sema::findMacroSpelling(SourceLocation &locref, StringRef name) { 1031 SourceLocation loc = locref; 1032 if (!loc.isMacroID()) return false; 1033 1034 // There's no good way right now to look at the intermediate 1035 // expansions, so just jump to the expansion location. 1036 loc = getSourceManager().getExpansionLoc(loc); 1037 1038 // If that's written with the name, stop here. 1039 SmallVector<char, 16> buffer; 1040 if (getPreprocessor().getSpelling(loc, buffer) == name) { 1041 locref = loc; 1042 return true; 1043 } 1044 return false; 1045 } 1046 1047 /// \brief Determines the active Scope associated with the given declaration 1048 /// context. 1049 /// 1050 /// This routine maps a declaration context to the active Scope object that 1051 /// represents that declaration context in the parser. It is typically used 1052 /// from "scope-less" code (e.g., template instantiation, lazy creation of 1053 /// declarations) that injects a name for name-lookup purposes and, therefore, 1054 /// must update the Scope. 1055 /// 1056 /// \returns The scope corresponding to the given declaraion context, or NULL 1057 /// if no such scope is open. 1058 Scope *Sema::getScopeForContext(DeclContext *Ctx) { 1059 1060 if (!Ctx) 1061 return nullptr; 1062 1063 Ctx = Ctx->getPrimaryContext(); 1064 for (Scope *S = getCurScope(); S; S = S->getParent()) { 1065 // Ignore scopes that cannot have declarations. This is important for 1066 // out-of-line definitions of static class members. 1067 if (S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) 1068 if (DeclContext *Entity = S->getEntity()) 1069 if (Ctx == Entity->getPrimaryContext()) 1070 return S; 1071 } 1072 1073 return nullptr; 1074 } 1075 1076 /// \brief Enter a new function scope 1077 void Sema::PushFunctionScope() { 1078 if (FunctionScopes.size() == 1) { 1079 // Use the "top" function scope rather than having to allocate 1080 // memory for a new scope. 1081 FunctionScopes.back()->Clear(); 1082 FunctionScopes.push_back(FunctionScopes.back()); 1083 return; 1084 } 1085 1086 FunctionScopes.push_back(new FunctionScopeInfo(getDiagnostics())); 1087 } 1088 1089 void Sema::PushBlockScope(Scope *BlockScope, BlockDecl *Block) { 1090 FunctionScopes.push_back(new BlockScopeInfo(getDiagnostics(), 1091 BlockScope, Block)); 1092 } 1093 1094 LambdaScopeInfo *Sema::PushLambdaScope() { 1095 LambdaScopeInfo *const LSI = new LambdaScopeInfo(getDiagnostics()); 1096 FunctionScopes.push_back(LSI); 1097 return LSI; 1098 } 1099 1100 void Sema::RecordParsingTemplateParameterDepth(unsigned Depth) { 1101 if (LambdaScopeInfo *const LSI = getCurLambda()) { 1102 LSI->AutoTemplateParameterDepth = Depth; 1103 return; 1104 } 1105 llvm_unreachable( 1106 "Remove assertion if intentionally called in a non-lambda context."); 1107 } 1108 1109 void Sema::PopFunctionScopeInfo(const AnalysisBasedWarnings::Policy *WP, 1110 const Decl *D, const BlockExpr *blkExpr) { 1111 FunctionScopeInfo *Scope = FunctionScopes.pop_back_val(); 1112 assert(!FunctionScopes.empty() && "mismatched push/pop!"); 1113 1114 // Issue any analysis-based warnings. 1115 if (WP && D) 1116 AnalysisWarnings.IssueWarnings(*WP, Scope, D, blkExpr); 1117 else 1118 for (const auto &PUD : Scope->PossiblyUnreachableDiags) 1119 Diag(PUD.Loc, PUD.PD); 1120 1121 if (FunctionScopes.back() != Scope) 1122 delete Scope; 1123 } 1124 1125 void Sema::PushCompoundScope() { 1126 getCurFunction()->CompoundScopes.push_back(CompoundScopeInfo()); 1127 } 1128 1129 void Sema::PopCompoundScope() { 1130 FunctionScopeInfo *CurFunction = getCurFunction(); 1131 assert(!CurFunction->CompoundScopes.empty() && "mismatched push/pop"); 1132 1133 CurFunction->CompoundScopes.pop_back(); 1134 } 1135 1136 /// \brief Determine whether any errors occurred within this function/method/ 1137 /// block. 1138 bool Sema::hasAnyUnrecoverableErrorsInThisFunction() const { 1139 return getCurFunction()->ErrorTrap.hasUnrecoverableErrorOccurred(); 1140 } 1141 1142 BlockScopeInfo *Sema::getCurBlock() { 1143 if (FunctionScopes.empty()) 1144 return nullptr; 1145 1146 auto CurBSI = dyn_cast<BlockScopeInfo>(FunctionScopes.back()); 1147 if (CurBSI && CurBSI->TheDecl && 1148 !CurBSI->TheDecl->Encloses(CurContext)) { 1149 // We have switched contexts due to template instantiation. 1150 assert(!ActiveTemplateInstantiations.empty()); 1151 return nullptr; 1152 } 1153 1154 return CurBSI; 1155 } 1156 1157 LambdaScopeInfo *Sema::getCurLambda() { 1158 if (FunctionScopes.empty()) 1159 return nullptr; 1160 1161 auto CurLSI = dyn_cast<LambdaScopeInfo>(FunctionScopes.back()); 1162 if (CurLSI && CurLSI->Lambda && 1163 !CurLSI->Lambda->Encloses(CurContext)) { 1164 // We have switched contexts due to template instantiation. 1165 assert(!ActiveTemplateInstantiations.empty()); 1166 return nullptr; 1167 } 1168 1169 return CurLSI; 1170 } 1171 // We have a generic lambda if we parsed auto parameters, or we have 1172 // an associated template parameter list. 1173 LambdaScopeInfo *Sema::getCurGenericLambda() { 1174 if (LambdaScopeInfo *LSI = getCurLambda()) { 1175 return (LSI->AutoTemplateParams.size() || 1176 LSI->GLTemplateParameterList) ? LSI : nullptr; 1177 } 1178 return nullptr; 1179 } 1180 1181 1182 void Sema::ActOnComment(SourceRange Comment) { 1183 if (!LangOpts.RetainCommentsFromSystemHeaders && 1184 SourceMgr.isInSystemHeader(Comment.getBegin())) 1185 return; 1186 RawComment RC(SourceMgr, Comment, false, 1187 LangOpts.CommentOpts.ParseAllComments); 1188 if (RC.isAlmostTrailingComment()) { 1189 SourceRange MagicMarkerRange(Comment.getBegin(), 1190 Comment.getBegin().getLocWithOffset(3)); 1191 StringRef MagicMarkerText; 1192 switch (RC.getKind()) { 1193 case RawComment::RCK_OrdinaryBCPL: 1194 MagicMarkerText = "///<"; 1195 break; 1196 case RawComment::RCK_OrdinaryC: 1197 MagicMarkerText = "/**<"; 1198 break; 1199 default: 1200 llvm_unreachable("if this is an almost Doxygen comment, " 1201 "it should be ordinary"); 1202 } 1203 Diag(Comment.getBegin(), diag::warn_not_a_doxygen_trailing_member_comment) << 1204 FixItHint::CreateReplacement(MagicMarkerRange, MagicMarkerText); 1205 } 1206 Context.addComment(RC); 1207 } 1208 1209 // Pin this vtable to this file. 1210 ExternalSemaSource::~ExternalSemaSource() {} 1211 1212 void ExternalSemaSource::ReadMethodPool(Selector Sel) { } 1213 1214 void ExternalSemaSource::ReadKnownNamespaces( 1215 SmallVectorImpl<NamespaceDecl *> &Namespaces) { 1216 } 1217 1218 void ExternalSemaSource::ReadUndefinedButUsed( 1219 llvm::DenseMap<NamedDecl *, SourceLocation> &Undefined) { 1220 } 1221 1222 void PrettyDeclStackTraceEntry::print(raw_ostream &OS) const { 1223 SourceLocation Loc = this->Loc; 1224 if (!Loc.isValid() && TheDecl) Loc = TheDecl->getLocation(); 1225 if (Loc.isValid()) { 1226 Loc.print(OS, S.getSourceManager()); 1227 OS << ": "; 1228 } 1229 OS << Message; 1230 1231 if (TheDecl && isa<NamedDecl>(TheDecl)) { 1232 std::string Name = cast<NamedDecl>(TheDecl)->getNameAsString(); 1233 if (!Name.empty()) 1234 OS << " '" << Name << '\''; 1235 } 1236 1237 OS << '\n'; 1238 } 1239 1240 /// \brief Figure out if an expression could be turned into a call. 1241 /// 1242 /// Use this when trying to recover from an error where the programmer may have 1243 /// written just the name of a function instead of actually calling it. 1244 /// 1245 /// \param E - The expression to examine. 1246 /// \param ZeroArgCallReturnTy - If the expression can be turned into a call 1247 /// with no arguments, this parameter is set to the type returned by such a 1248 /// call; otherwise, it is set to an empty QualType. 1249 /// \param OverloadSet - If the expression is an overloaded function 1250 /// name, this parameter is populated with the decls of the various overloads. 1251 bool Sema::tryExprAsCall(Expr &E, QualType &ZeroArgCallReturnTy, 1252 UnresolvedSetImpl &OverloadSet) { 1253 ZeroArgCallReturnTy = QualType(); 1254 OverloadSet.clear(); 1255 1256 const OverloadExpr *Overloads = nullptr; 1257 bool IsMemExpr = false; 1258 if (E.getType() == Context.OverloadTy) { 1259 OverloadExpr::FindResult FR = OverloadExpr::find(const_cast<Expr*>(&E)); 1260 1261 // Ignore overloads that are pointer-to-member constants. 1262 if (FR.HasFormOfMemberPointer) 1263 return false; 1264 1265 Overloads = FR.Expression; 1266 } else if (E.getType() == Context.BoundMemberTy) { 1267 Overloads = dyn_cast<UnresolvedMemberExpr>(E.IgnoreParens()); 1268 IsMemExpr = true; 1269 } 1270 1271 bool Ambiguous = false; 1272 1273 if (Overloads) { 1274 for (OverloadExpr::decls_iterator it = Overloads->decls_begin(), 1275 DeclsEnd = Overloads->decls_end(); it != DeclsEnd; ++it) { 1276 OverloadSet.addDecl(*it); 1277 1278 // Check whether the function is a non-template, non-member which takes no 1279 // arguments. 1280 if (IsMemExpr) 1281 continue; 1282 if (const FunctionDecl *OverloadDecl 1283 = dyn_cast<FunctionDecl>((*it)->getUnderlyingDecl())) { 1284 if (OverloadDecl->getMinRequiredArguments() == 0) { 1285 if (!ZeroArgCallReturnTy.isNull() && !Ambiguous) { 1286 ZeroArgCallReturnTy = QualType(); 1287 Ambiguous = true; 1288 } else 1289 ZeroArgCallReturnTy = OverloadDecl->getReturnType(); 1290 } 1291 } 1292 } 1293 1294 // If it's not a member, use better machinery to try to resolve the call 1295 if (!IsMemExpr) 1296 return !ZeroArgCallReturnTy.isNull(); 1297 } 1298 1299 // Attempt to call the member with no arguments - this will correctly handle 1300 // member templates with defaults/deduction of template arguments, overloads 1301 // with default arguments, etc. 1302 if (IsMemExpr && !E.isTypeDependent()) { 1303 bool Suppress = getDiagnostics().getSuppressAllDiagnostics(); 1304 getDiagnostics().setSuppressAllDiagnostics(true); 1305 ExprResult R = BuildCallToMemberFunction(nullptr, &E, SourceLocation(), 1306 None, SourceLocation()); 1307 getDiagnostics().setSuppressAllDiagnostics(Suppress); 1308 if (R.isUsable()) { 1309 ZeroArgCallReturnTy = R.get()->getType(); 1310 return true; 1311 } 1312 return false; 1313 } 1314 1315 if (const DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E.IgnoreParens())) { 1316 if (const FunctionDecl *Fun = dyn_cast<FunctionDecl>(DeclRef->getDecl())) { 1317 if (Fun->getMinRequiredArguments() == 0) 1318 ZeroArgCallReturnTy = Fun->getReturnType(); 1319 return true; 1320 } 1321 } 1322 1323 // We don't have an expression that's convenient to get a FunctionDecl from, 1324 // but we can at least check if the type is "function of 0 arguments". 1325 QualType ExprTy = E.getType(); 1326 const FunctionType *FunTy = nullptr; 1327 QualType PointeeTy = ExprTy->getPointeeType(); 1328 if (!PointeeTy.isNull()) 1329 FunTy = PointeeTy->getAs<FunctionType>(); 1330 if (!FunTy) 1331 FunTy = ExprTy->getAs<FunctionType>(); 1332 1333 if (const FunctionProtoType *FPT = 1334 dyn_cast_or_null<FunctionProtoType>(FunTy)) { 1335 if (FPT->getNumParams() == 0) 1336 ZeroArgCallReturnTy = FunTy->getReturnType(); 1337 return true; 1338 } 1339 return false; 1340 } 1341 1342 /// \brief Give notes for a set of overloads. 1343 /// 1344 /// A companion to tryExprAsCall. In cases when the name that the programmer 1345 /// wrote was an overloaded function, we may be able to make some guesses about 1346 /// plausible overloads based on their return types; such guesses can be handed 1347 /// off to this method to be emitted as notes. 1348 /// 1349 /// \param Overloads - The overloads to note. 1350 /// \param FinalNoteLoc - If we've suppressed printing some overloads due to 1351 /// -fshow-overloads=best, this is the location to attach to the note about too 1352 /// many candidates. Typically this will be the location of the original 1353 /// ill-formed expression. 1354 static void noteOverloads(Sema &S, const UnresolvedSetImpl &Overloads, 1355 const SourceLocation FinalNoteLoc) { 1356 int ShownOverloads = 0; 1357 int SuppressedOverloads = 0; 1358 for (UnresolvedSetImpl::iterator It = Overloads.begin(), 1359 DeclsEnd = Overloads.end(); It != DeclsEnd; ++It) { 1360 // FIXME: Magic number for max shown overloads stolen from 1361 // OverloadCandidateSet::NoteCandidates. 1362 if (ShownOverloads >= 4 && S.Diags.getShowOverloads() == Ovl_Best) { 1363 ++SuppressedOverloads; 1364 continue; 1365 } 1366 1367 NamedDecl *Fn = (*It)->getUnderlyingDecl(); 1368 S.Diag(Fn->getLocation(), diag::note_possible_target_of_call); 1369 ++ShownOverloads; 1370 } 1371 1372 if (SuppressedOverloads) 1373 S.Diag(FinalNoteLoc, diag::note_ovl_too_many_candidates) 1374 << SuppressedOverloads; 1375 } 1376 1377 static void notePlausibleOverloads(Sema &S, SourceLocation Loc, 1378 const UnresolvedSetImpl &Overloads, 1379 bool (*IsPlausibleResult)(QualType)) { 1380 if (!IsPlausibleResult) 1381 return noteOverloads(S, Overloads, Loc); 1382 1383 UnresolvedSet<2> PlausibleOverloads; 1384 for (OverloadExpr::decls_iterator It = Overloads.begin(), 1385 DeclsEnd = Overloads.end(); It != DeclsEnd; ++It) { 1386 const FunctionDecl *OverloadDecl = cast<FunctionDecl>(*It); 1387 QualType OverloadResultTy = OverloadDecl->getReturnType(); 1388 if (IsPlausibleResult(OverloadResultTy)) 1389 PlausibleOverloads.addDecl(It.getDecl()); 1390 } 1391 noteOverloads(S, PlausibleOverloads, Loc); 1392 } 1393 1394 /// Determine whether the given expression can be called by just 1395 /// putting parentheses after it. Notably, expressions with unary 1396 /// operators can't be because the unary operator will start parsing 1397 /// outside the call. 1398 static bool IsCallableWithAppend(Expr *E) { 1399 E = E->IgnoreImplicit(); 1400 return (!isa<CStyleCastExpr>(E) && 1401 !isa<UnaryOperator>(E) && 1402 !isa<BinaryOperator>(E) && 1403 !isa<CXXOperatorCallExpr>(E)); 1404 } 1405 1406 bool Sema::tryToRecoverWithCall(ExprResult &E, const PartialDiagnostic &PD, 1407 bool ForceComplain, 1408 bool (*IsPlausibleResult)(QualType)) { 1409 SourceLocation Loc = E.get()->getExprLoc(); 1410 SourceRange Range = E.get()->getSourceRange(); 1411 1412 QualType ZeroArgCallTy; 1413 UnresolvedSet<4> Overloads; 1414 if (tryExprAsCall(*E.get(), ZeroArgCallTy, Overloads) && 1415 !ZeroArgCallTy.isNull() && 1416 (!IsPlausibleResult || IsPlausibleResult(ZeroArgCallTy))) { 1417 // At this point, we know E is potentially callable with 0 1418 // arguments and that it returns something of a reasonable type, 1419 // so we can emit a fixit and carry on pretending that E was 1420 // actually a CallExpr. 1421 SourceLocation ParenInsertionLoc = PP.getLocForEndOfToken(Range.getEnd()); 1422 Diag(Loc, PD) 1423 << /*zero-arg*/ 1 << Range 1424 << (IsCallableWithAppend(E.get()) 1425 ? FixItHint::CreateInsertion(ParenInsertionLoc, "()") 1426 : FixItHint()); 1427 notePlausibleOverloads(*this, Loc, Overloads, IsPlausibleResult); 1428 1429 // FIXME: Try this before emitting the fixit, and suppress diagnostics 1430 // while doing so. 1431 E = ActOnCallExpr(nullptr, E.get(), Range.getEnd(), None, 1432 Range.getEnd().getLocWithOffset(1)); 1433 return true; 1434 } 1435 1436 if (!ForceComplain) return false; 1437 1438 Diag(Loc, PD) << /*not zero-arg*/ 0 << Range; 1439 notePlausibleOverloads(*this, Loc, Overloads, IsPlausibleResult); 1440 E = ExprError(); 1441 return true; 1442 } 1443 1444 IdentifierInfo *Sema::getSuperIdentifier() const { 1445 if (!Ident_super) 1446 Ident_super = &Context.Idents.get("super"); 1447 return Ident_super; 1448 } 1449 1450 IdentifierInfo *Sema::getFloat128Identifier() const { 1451 if (!Ident___float128) 1452 Ident___float128 = &Context.Idents.get("__float128"); 1453 return Ident___float128; 1454 } 1455 1456 void Sema::PushCapturedRegionScope(Scope *S, CapturedDecl *CD, RecordDecl *RD, 1457 CapturedRegionKind K) { 1458 CapturingScopeInfo *CSI = new CapturedRegionScopeInfo( 1459 getDiagnostics(), S, CD, RD, CD->getContextParam(), K); 1460 CSI->ReturnType = Context.VoidTy; 1461 FunctionScopes.push_back(CSI); 1462 } 1463 1464 CapturedRegionScopeInfo *Sema::getCurCapturedRegion() { 1465 if (FunctionScopes.empty()) 1466 return nullptr; 1467 1468 return dyn_cast<CapturedRegionScopeInfo>(FunctionScopes.back()); 1469 } 1470