1 //===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===// 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 /// \file 11 /// \brief Implements semantic analysis for C++ expressions. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #include "clang/Sema/SemaInternal.h" 16 #include "TypeLocBuilder.h" 17 #include "clang/AST/ASTContext.h" 18 #include "clang/AST/CXXInheritance.h" 19 #include "clang/AST/CharUnits.h" 20 #include "clang/AST/DeclObjC.h" 21 #include "clang/AST/EvaluatedExprVisitor.h" 22 #include "clang/AST/ExprCXX.h" 23 #include "clang/AST/ExprObjC.h" 24 #include "clang/AST/TypeLoc.h" 25 #include "clang/Basic/PartialDiagnostic.h" 26 #include "clang/Basic/TargetInfo.h" 27 #include "clang/Lex/Preprocessor.h" 28 #include "clang/Sema/DeclSpec.h" 29 #include "clang/Sema/Initialization.h" 30 #include "clang/Sema/Lookup.h" 31 #include "clang/Sema/ParsedTemplate.h" 32 #include "clang/Sema/Scope.h" 33 #include "clang/Sema/ScopeInfo.h" 34 #include "clang/Sema/TemplateDeduction.h" 35 #include "llvm/ADT/APInt.h" 36 #include "llvm/ADT/STLExtras.h" 37 #include "llvm/Support/ErrorHandling.h" 38 using namespace clang; 39 using namespace sema; 40 41 ParsedType Sema::getDestructorName(SourceLocation TildeLoc, 42 IdentifierInfo &II, 43 SourceLocation NameLoc, 44 Scope *S, CXXScopeSpec &SS, 45 ParsedType ObjectTypePtr, 46 bool EnteringContext) { 47 // Determine where to perform name lookup. 48 49 // FIXME: This area of the standard is very messy, and the current 50 // wording is rather unclear about which scopes we search for the 51 // destructor name; see core issues 399 and 555. Issue 399 in 52 // particular shows where the current description of destructor name 53 // lookup is completely out of line with existing practice, e.g., 54 // this appears to be ill-formed: 55 // 56 // namespace N { 57 // template <typename T> struct S { 58 // ~S(); 59 // }; 60 // } 61 // 62 // void f(N::S<int>* s) { 63 // s->N::S<int>::~S(); 64 // } 65 // 66 // See also PR6358 and PR6359. 67 // For this reason, we're currently only doing the C++03 version of this 68 // code; the C++0x version has to wait until we get a proper spec. 69 QualType SearchType; 70 DeclContext *LookupCtx = 0; 71 bool isDependent = false; 72 bool LookInScope = false; 73 74 // If we have an object type, it's because we are in a 75 // pseudo-destructor-expression or a member access expression, and 76 // we know what type we're looking for. 77 if (ObjectTypePtr) 78 SearchType = GetTypeFromParser(ObjectTypePtr); 79 80 if (SS.isSet()) { 81 NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 82 83 bool AlreadySearched = false; 84 bool LookAtPrefix = true; 85 // C++ [basic.lookup.qual]p6: 86 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier, 87 // the type-names are looked up as types in the scope designated by the 88 // nested-name-specifier. In a qualified-id of the form: 89 // 90 // ::[opt] nested-name-specifier ~ class-name 91 // 92 // where the nested-name-specifier designates a namespace scope, and in 93 // a qualified-id of the form: 94 // 95 // ::opt nested-name-specifier class-name :: ~ class-name 96 // 97 // the class-names are looked up as types in the scope designated by 98 // the nested-name-specifier. 99 // 100 // Here, we check the first case (completely) and determine whether the 101 // code below is permitted to look at the prefix of the 102 // nested-name-specifier. 103 DeclContext *DC = computeDeclContext(SS, EnteringContext); 104 if (DC && DC->isFileContext()) { 105 AlreadySearched = true; 106 LookupCtx = DC; 107 isDependent = false; 108 } else if (DC && isa<CXXRecordDecl>(DC)) 109 LookAtPrefix = false; 110 111 // The second case from the C++03 rules quoted further above. 112 NestedNameSpecifier *Prefix = 0; 113 if (AlreadySearched) { 114 // Nothing left to do. 115 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) { 116 CXXScopeSpec PrefixSS; 117 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data())); 118 LookupCtx = computeDeclContext(PrefixSS, EnteringContext); 119 isDependent = isDependentScopeSpecifier(PrefixSS); 120 } else if (ObjectTypePtr) { 121 LookupCtx = computeDeclContext(SearchType); 122 isDependent = SearchType->isDependentType(); 123 } else { 124 LookupCtx = computeDeclContext(SS, EnteringContext); 125 isDependent = LookupCtx && LookupCtx->isDependentContext(); 126 } 127 128 LookInScope = false; 129 } else if (ObjectTypePtr) { 130 // C++ [basic.lookup.classref]p3: 131 // If the unqualified-id is ~type-name, the type-name is looked up 132 // in the context of the entire postfix-expression. If the type T 133 // of the object expression is of a class type C, the type-name is 134 // also looked up in the scope of class C. At least one of the 135 // lookups shall find a name that refers to (possibly 136 // cv-qualified) T. 137 LookupCtx = computeDeclContext(SearchType); 138 isDependent = SearchType->isDependentType(); 139 assert((isDependent || !SearchType->isIncompleteType()) && 140 "Caller should have completed object type"); 141 142 LookInScope = true; 143 } else { 144 // Perform lookup into the current scope (only). 145 LookInScope = true; 146 } 147 148 TypeDecl *NonMatchingTypeDecl = 0; 149 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName); 150 for (unsigned Step = 0; Step != 2; ++Step) { 151 // Look for the name first in the computed lookup context (if we 152 // have one) and, if that fails to find a match, in the scope (if 153 // we're allowed to look there). 154 Found.clear(); 155 if (Step == 0 && LookupCtx) 156 LookupQualifiedName(Found, LookupCtx); 157 else if (Step == 1 && LookInScope && S) 158 LookupName(Found, S); 159 else 160 continue; 161 162 // FIXME: Should we be suppressing ambiguities here? 163 if (Found.isAmbiguous()) 164 return ParsedType(); 165 166 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) { 167 QualType T = Context.getTypeDeclType(Type); 168 169 if (SearchType.isNull() || SearchType->isDependentType() || 170 Context.hasSameUnqualifiedType(T, SearchType)) { 171 // We found our type! 172 173 return ParsedType::make(T); 174 } 175 176 if (!SearchType.isNull()) 177 NonMatchingTypeDecl = Type; 178 } 179 180 // If the name that we found is a class template name, and it is 181 // the same name as the template name in the last part of the 182 // nested-name-specifier (if present) or the object type, then 183 // this is the destructor for that class. 184 // FIXME: This is a workaround until we get real drafting for core 185 // issue 399, for which there isn't even an obvious direction. 186 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) { 187 QualType MemberOfType; 188 if (SS.isSet()) { 189 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) { 190 // Figure out the type of the context, if it has one. 191 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) 192 MemberOfType = Context.getTypeDeclType(Record); 193 } 194 } 195 if (MemberOfType.isNull()) 196 MemberOfType = SearchType; 197 198 if (MemberOfType.isNull()) 199 continue; 200 201 // We're referring into a class template specialization. If the 202 // class template we found is the same as the template being 203 // specialized, we found what we are looking for. 204 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) { 205 if (ClassTemplateSpecializationDecl *Spec 206 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) { 207 if (Spec->getSpecializedTemplate()->getCanonicalDecl() == 208 Template->getCanonicalDecl()) 209 return ParsedType::make(MemberOfType); 210 } 211 212 continue; 213 } 214 215 // We're referring to an unresolved class template 216 // specialization. Determine whether we class template we found 217 // is the same as the template being specialized or, if we don't 218 // know which template is being specialized, that it at least 219 // has the same name. 220 if (const TemplateSpecializationType *SpecType 221 = MemberOfType->getAs<TemplateSpecializationType>()) { 222 TemplateName SpecName = SpecType->getTemplateName(); 223 224 // The class template we found is the same template being 225 // specialized. 226 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) { 227 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl()) 228 return ParsedType::make(MemberOfType); 229 230 continue; 231 } 232 233 // The class template we found has the same name as the 234 // (dependent) template name being specialized. 235 if (DependentTemplateName *DepTemplate 236 = SpecName.getAsDependentTemplateName()) { 237 if (DepTemplate->isIdentifier() && 238 DepTemplate->getIdentifier() == Template->getIdentifier()) 239 return ParsedType::make(MemberOfType); 240 241 continue; 242 } 243 } 244 } 245 } 246 247 if (isDependent) { 248 // We didn't find our type, but that's okay: it's dependent 249 // anyway. 250 251 // FIXME: What if we have no nested-name-specifier? 252 QualType T = CheckTypenameType(ETK_None, SourceLocation(), 253 SS.getWithLocInContext(Context), 254 II, NameLoc); 255 return ParsedType::make(T); 256 } 257 258 if (NonMatchingTypeDecl) { 259 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl); 260 Diag(NameLoc, diag::err_destructor_expr_type_mismatch) 261 << T << SearchType; 262 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here) 263 << T; 264 } else if (ObjectTypePtr) 265 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type) 266 << &II; 267 else 268 Diag(NameLoc, diag::err_destructor_class_name); 269 270 return ParsedType(); 271 } 272 273 ParsedType Sema::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) { 274 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType) 275 return ParsedType(); 276 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype 277 && "only get destructor types from declspecs"); 278 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 279 QualType SearchType = GetTypeFromParser(ObjectType); 280 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) { 281 return ParsedType::make(T); 282 } 283 284 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch) 285 << T << SearchType; 286 return ParsedType(); 287 } 288 289 /// \brief Build a C++ typeid expression with a type operand. 290 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 291 SourceLocation TypeidLoc, 292 TypeSourceInfo *Operand, 293 SourceLocation RParenLoc) { 294 // C++ [expr.typeid]p4: 295 // The top-level cv-qualifiers of the lvalue expression or the type-id 296 // that is the operand of typeid are always ignored. 297 // If the type of the type-id is a class type or a reference to a class 298 // type, the class shall be completely-defined. 299 Qualifiers Quals; 300 QualType T 301 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(), 302 Quals); 303 if (T->getAs<RecordType>() && 304 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 305 return ExprError(); 306 307 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 308 Operand, 309 SourceRange(TypeidLoc, RParenLoc))); 310 } 311 312 /// \brief Build a C++ typeid expression with an expression operand. 313 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 314 SourceLocation TypeidLoc, 315 Expr *E, 316 SourceLocation RParenLoc) { 317 if (E && !E->isTypeDependent()) { 318 if (E->getType()->isPlaceholderType()) { 319 ExprResult result = CheckPlaceholderExpr(E); 320 if (result.isInvalid()) return ExprError(); 321 E = result.take(); 322 } 323 324 QualType T = E->getType(); 325 if (const RecordType *RecordT = T->getAs<RecordType>()) { 326 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl()); 327 // C++ [expr.typeid]p3: 328 // [...] If the type of the expression is a class type, the class 329 // shall be completely-defined. 330 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 331 return ExprError(); 332 333 // C++ [expr.typeid]p3: 334 // When typeid is applied to an expression other than an glvalue of a 335 // polymorphic class type [...] [the] expression is an unevaluated 336 // operand. [...] 337 if (RecordD->isPolymorphic() && E->isGLValue()) { 338 // The subexpression is potentially evaluated; switch the context 339 // and recheck the subexpression. 340 ExprResult Result = TransformToPotentiallyEvaluated(E); 341 if (Result.isInvalid()) return ExprError(); 342 E = Result.take(); 343 344 // We require a vtable to query the type at run time. 345 MarkVTableUsed(TypeidLoc, RecordD); 346 } 347 } 348 349 // C++ [expr.typeid]p4: 350 // [...] If the type of the type-id is a reference to a possibly 351 // cv-qualified type, the result of the typeid expression refers to a 352 // std::type_info object representing the cv-unqualified referenced 353 // type. 354 Qualifiers Quals; 355 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals); 356 if (!Context.hasSameType(T, UnqualT)) { 357 T = UnqualT; 358 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).take(); 359 } 360 } 361 362 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 363 E, 364 SourceRange(TypeidLoc, RParenLoc))); 365 } 366 367 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression); 368 ExprResult 369 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc, 370 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 371 // Find the std::type_info type. 372 if (!getStdNamespace()) 373 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 374 375 if (!CXXTypeInfoDecl) { 376 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info"); 377 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName); 378 LookupQualifiedName(R, getStdNamespace()); 379 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 380 // Microsoft's typeinfo doesn't have type_info in std but in the global 381 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153. 382 if (!CXXTypeInfoDecl && LangOpts.MicrosoftMode) { 383 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 384 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 385 } 386 if (!CXXTypeInfoDecl) 387 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 388 } 389 390 if (!getLangOpts().RTTI) { 391 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti)); 392 } 393 394 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl); 395 396 if (isType) { 397 // The operand is a type; handle it as such. 398 TypeSourceInfo *TInfo = 0; 399 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 400 &TInfo); 401 if (T.isNull()) 402 return ExprError(); 403 404 if (!TInfo) 405 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 406 407 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc); 408 } 409 410 // The operand is an expression. 411 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 412 } 413 414 /// \brief Build a Microsoft __uuidof expression with a type operand. 415 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 416 SourceLocation TypeidLoc, 417 TypeSourceInfo *Operand, 418 SourceLocation RParenLoc) { 419 if (!Operand->getType()->isDependentType()) { 420 if (!CXXUuidofExpr::GetUuidAttrOfType(Operand->getType())) 421 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 422 } 423 424 // FIXME: add __uuidof semantic analysis for type operand. 425 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 426 Operand, 427 SourceRange(TypeidLoc, RParenLoc))); 428 } 429 430 /// \brief Build a Microsoft __uuidof expression with an expression operand. 431 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 432 SourceLocation TypeidLoc, 433 Expr *E, 434 SourceLocation RParenLoc) { 435 if (!E->getType()->isDependentType()) { 436 if (!CXXUuidofExpr::GetUuidAttrOfType(E->getType()) && 437 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 438 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 439 } 440 // FIXME: add __uuidof semantic analysis for type operand. 441 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 442 E, 443 SourceRange(TypeidLoc, RParenLoc))); 444 } 445 446 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression); 447 ExprResult 448 Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc, 449 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 450 // If MSVCGuidDecl has not been cached, do the lookup. 451 if (!MSVCGuidDecl) { 452 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID"); 453 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName); 454 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 455 MSVCGuidDecl = R.getAsSingle<RecordDecl>(); 456 if (!MSVCGuidDecl) 457 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof)); 458 } 459 460 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl); 461 462 if (isType) { 463 // The operand is a type; handle it as such. 464 TypeSourceInfo *TInfo = 0; 465 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 466 &TInfo); 467 if (T.isNull()) 468 return ExprError(); 469 470 if (!TInfo) 471 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 472 473 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc); 474 } 475 476 // The operand is an expression. 477 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 478 } 479 480 /// ActOnCXXBoolLiteral - Parse {true,false} literals. 481 ExprResult 482 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 483 assert((Kind == tok::kw_true || Kind == tok::kw_false) && 484 "Unknown C++ Boolean value!"); 485 return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true, 486 Context.BoolTy, OpLoc)); 487 } 488 489 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'. 490 ExprResult 491 Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) { 492 return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc)); 493 } 494 495 /// ActOnCXXThrow - Parse throw expressions. 496 ExprResult 497 Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) { 498 bool IsThrownVarInScope = false; 499 if (Ex) { 500 // C++0x [class.copymove]p31: 501 // When certain criteria are met, an implementation is allowed to omit the 502 // copy/move construction of a class object [...] 503 // 504 // - in a throw-expression, when the operand is the name of a 505 // non-volatile automatic object (other than a function or catch- 506 // clause parameter) whose scope does not extend beyond the end of the 507 // innermost enclosing try-block (if there is one), the copy/move 508 // operation from the operand to the exception object (15.1) can be 509 // omitted by constructing the automatic object directly into the 510 // exception object 511 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens())) 512 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 513 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) { 514 for( ; S; S = S->getParent()) { 515 if (S->isDeclScope(Var)) { 516 IsThrownVarInScope = true; 517 break; 518 } 519 520 if (S->getFlags() & 521 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope | 522 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope | 523 Scope::TryScope)) 524 break; 525 } 526 } 527 } 528 } 529 530 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope); 531 } 532 533 ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex, 534 bool IsThrownVarInScope) { 535 // Don't report an error if 'throw' is used in system headers. 536 if (!getLangOpts().CXXExceptions && 537 !getSourceManager().isInSystemHeader(OpLoc)) 538 Diag(OpLoc, diag::err_exceptions_disabled) << "throw"; 539 540 if (Ex && !Ex->isTypeDependent()) { 541 ExprResult ExRes = CheckCXXThrowOperand(OpLoc, Ex, IsThrownVarInScope); 542 if (ExRes.isInvalid()) 543 return ExprError(); 544 Ex = ExRes.take(); 545 } 546 547 return Owned(new (Context) CXXThrowExpr(Ex, Context.VoidTy, OpLoc, 548 IsThrownVarInScope)); 549 } 550 551 /// CheckCXXThrowOperand - Validate the operand of a throw. 552 ExprResult Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *E, 553 bool IsThrownVarInScope) { 554 // C++ [except.throw]p3: 555 // A throw-expression initializes a temporary object, called the exception 556 // object, the type of which is determined by removing any top-level 557 // cv-qualifiers from the static type of the operand of throw and adjusting 558 // the type from "array of T" or "function returning T" to "pointer to T" 559 // or "pointer to function returning T", [...] 560 if (E->getType().hasQualifiers()) 561 E = ImpCastExprToType(E, E->getType().getUnqualifiedType(), CK_NoOp, 562 E->getValueKind()).take(); 563 564 ExprResult Res = DefaultFunctionArrayConversion(E); 565 if (Res.isInvalid()) 566 return ExprError(); 567 E = Res.take(); 568 569 // If the type of the exception would be an incomplete type or a pointer 570 // to an incomplete type other than (cv) void the program is ill-formed. 571 QualType Ty = E->getType(); 572 bool isPointer = false; 573 if (const PointerType* Ptr = Ty->getAs<PointerType>()) { 574 Ty = Ptr->getPointeeType(); 575 isPointer = true; 576 } 577 if (!isPointer || !Ty->isVoidType()) { 578 if (RequireCompleteType(ThrowLoc, Ty, 579 isPointer? diag::err_throw_incomplete_ptr 580 : diag::err_throw_incomplete, 581 E->getSourceRange())) 582 return ExprError(); 583 584 if (RequireNonAbstractType(ThrowLoc, E->getType(), 585 diag::err_throw_abstract_type, E)) 586 return ExprError(); 587 } 588 589 // Initialize the exception result. This implicitly weeds out 590 // abstract types or types with inaccessible copy constructors. 591 592 // C++0x [class.copymove]p31: 593 // When certain criteria are met, an implementation is allowed to omit the 594 // copy/move construction of a class object [...] 595 // 596 // - in a throw-expression, when the operand is the name of a 597 // non-volatile automatic object (other than a function or catch-clause 598 // parameter) whose scope does not extend beyond the end of the 599 // innermost enclosing try-block (if there is one), the copy/move 600 // operation from the operand to the exception object (15.1) can be 601 // omitted by constructing the automatic object directly into the 602 // exception object 603 const VarDecl *NRVOVariable = 0; 604 if (IsThrownVarInScope) 605 NRVOVariable = getCopyElisionCandidate(QualType(), E, false); 606 607 InitializedEntity Entity = 608 InitializedEntity::InitializeException(ThrowLoc, E->getType(), 609 /*NRVO=*/NRVOVariable != 0); 610 Res = PerformMoveOrCopyInitialization(Entity, NRVOVariable, 611 QualType(), E, 612 IsThrownVarInScope); 613 if (Res.isInvalid()) 614 return ExprError(); 615 E = Res.take(); 616 617 // If the exception has class type, we need additional handling. 618 const RecordType *RecordTy = Ty->getAs<RecordType>(); 619 if (!RecordTy) 620 return Owned(E); 621 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl()); 622 623 // If we are throwing a polymorphic class type or pointer thereof, 624 // exception handling will make use of the vtable. 625 MarkVTableUsed(ThrowLoc, RD); 626 627 // If a pointer is thrown, the referenced object will not be destroyed. 628 if (isPointer) 629 return Owned(E); 630 631 // If the class has a destructor, we must be able to call it. 632 if (RD->hasIrrelevantDestructor()) 633 return Owned(E); 634 635 CXXDestructorDecl *Destructor = LookupDestructor(RD); 636 if (!Destructor) 637 return Owned(E); 638 639 MarkFunctionReferenced(E->getExprLoc(), Destructor); 640 CheckDestructorAccess(E->getExprLoc(), Destructor, 641 PDiag(diag::err_access_dtor_exception) << Ty); 642 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 643 return Owned(E); 644 } 645 646 QualType Sema::getCurrentThisType() { 647 DeclContext *DC = getFunctionLevelDeclContext(); 648 QualType ThisTy = CXXThisTypeOverride; 649 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) { 650 if (method && method->isInstance()) 651 ThisTy = method->getThisType(Context); 652 } 653 654 return ThisTy; 655 } 656 657 Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S, 658 Decl *ContextDecl, 659 unsigned CXXThisTypeQuals, 660 bool Enabled) 661 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false) 662 { 663 if (!Enabled || !ContextDecl) 664 return; 665 666 CXXRecordDecl *Record = 0; 667 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl)) 668 Record = Template->getTemplatedDecl(); 669 else 670 Record = cast<CXXRecordDecl>(ContextDecl); 671 672 S.CXXThisTypeOverride 673 = S.Context.getPointerType( 674 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals)); 675 676 this->Enabled = true; 677 } 678 679 680 Sema::CXXThisScopeRAII::~CXXThisScopeRAII() { 681 if (Enabled) { 682 S.CXXThisTypeOverride = OldCXXThisTypeOverride; 683 } 684 } 685 686 void Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit) { 687 // We don't need to capture this in an unevaluated context. 688 if (ExprEvalContexts.back().Context == Unevaluated && !Explicit) 689 return; 690 691 // Otherwise, check that we can capture 'this'. 692 unsigned NumClosures = 0; 693 for (unsigned idx = FunctionScopes.size() - 1; idx != 0; idx--) { 694 if (CapturingScopeInfo *CSI = 695 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) { 696 if (CSI->CXXThisCaptureIndex != 0) { 697 // 'this' is already being captured; there isn't anything more to do. 698 break; 699 } 700 701 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref || 702 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval || 703 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block || 704 Explicit) { 705 // This closure can capture 'this'; continue looking upwards. 706 NumClosures++; 707 Explicit = false; 708 continue; 709 } 710 // This context can't implicitly capture 'this'; fail out. 711 Diag(Loc, diag::err_this_capture) << Explicit; 712 return; 713 } 714 break; 715 } 716 717 // Mark that we're implicitly capturing 'this' in all the scopes we skipped. 718 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated 719 // contexts. 720 for (unsigned idx = FunctionScopes.size() - 1; 721 NumClosures; --idx, --NumClosures) { 722 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]); 723 Expr *ThisExpr = 0; 724 QualType ThisTy = getCurrentThisType(); 725 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) { 726 // For lambda expressions, build a field and an initializing expression. 727 CXXRecordDecl *Lambda = LSI->Lambda; 728 FieldDecl *Field 729 = FieldDecl::Create(Context, Lambda, Loc, Loc, 0, ThisTy, 730 Context.getTrivialTypeSourceInfo(ThisTy, Loc), 731 0, false, ICIS_NoInit); 732 Field->setImplicit(true); 733 Field->setAccess(AS_private); 734 Lambda->addDecl(Field); 735 ThisExpr = new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/true); 736 } 737 bool isNested = NumClosures > 1; 738 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr); 739 } 740 } 741 742 ExprResult Sema::ActOnCXXThis(SourceLocation Loc) { 743 /// C++ 9.3.2: In the body of a non-static member function, the keyword this 744 /// is a non-lvalue expression whose value is the address of the object for 745 /// which the function is called. 746 747 QualType ThisTy = getCurrentThisType(); 748 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use); 749 750 CheckCXXThisCapture(Loc); 751 return Owned(new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false)); 752 } 753 754 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) { 755 // If we're outside the body of a member function, then we'll have a specified 756 // type for 'this'. 757 if (CXXThisTypeOverride.isNull()) 758 return false; 759 760 // Determine whether we're looking into a class that's currently being 761 // defined. 762 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl(); 763 return Class && Class->isBeingDefined(); 764 } 765 766 ExprResult 767 Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep, 768 SourceLocation LParenLoc, 769 MultiExprArg exprs, 770 SourceLocation RParenLoc) { 771 if (!TypeRep) 772 return ExprError(); 773 774 TypeSourceInfo *TInfo; 775 QualType Ty = GetTypeFromParser(TypeRep, &TInfo); 776 if (!TInfo) 777 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation()); 778 779 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc); 780 } 781 782 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type. 783 /// Can be interpreted either as function-style casting ("int(x)") 784 /// or class type construction ("ClassType(x,y,z)") 785 /// or creation of a value-initialized type ("int()"). 786 ExprResult 787 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, 788 SourceLocation LParenLoc, 789 MultiExprArg exprs, 790 SourceLocation RParenLoc) { 791 QualType Ty = TInfo->getType(); 792 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); 793 794 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(exprs)) { 795 return Owned(CXXUnresolvedConstructExpr::Create(Context, TInfo, 796 LParenLoc, 797 exprs, 798 RParenLoc)); 799 } 800 801 unsigned NumExprs = exprs.size(); 802 Expr **Exprs = exprs.data(); 803 804 bool ListInitialization = LParenLoc.isInvalid(); 805 assert((!ListInitialization || (NumExprs == 1 && isa<InitListExpr>(Exprs[0]))) 806 && "List initialization must have initializer list as expression."); 807 SourceRange FullRange = SourceRange(TyBeginLoc, 808 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc); 809 810 // C++ [expr.type.conv]p1: 811 // If the expression list is a single expression, the type conversion 812 // expression is equivalent (in definedness, and if defined in meaning) to the 813 // corresponding cast expression. 814 if (NumExprs == 1 && !ListInitialization) { 815 Expr *Arg = Exprs[0]; 816 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc); 817 } 818 819 QualType ElemTy = Ty; 820 if (Ty->isArrayType()) { 821 if (!ListInitialization) 822 return ExprError(Diag(TyBeginLoc, 823 diag::err_value_init_for_array_type) << FullRange); 824 ElemTy = Context.getBaseElementType(Ty); 825 } 826 827 if (!Ty->isVoidType() && 828 RequireCompleteType(TyBeginLoc, ElemTy, 829 diag::err_invalid_incomplete_type_use, FullRange)) 830 return ExprError(); 831 832 if (RequireNonAbstractType(TyBeginLoc, Ty, 833 diag::err_allocation_of_abstract_type)) 834 return ExprError(); 835 836 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo); 837 InitializationKind Kind 838 = NumExprs ? ListInitialization 839 ? InitializationKind::CreateDirectList(TyBeginLoc) 840 : InitializationKind::CreateDirect(TyBeginLoc, 841 LParenLoc, RParenLoc) 842 : InitializationKind::CreateValue(TyBeginLoc, 843 LParenLoc, RParenLoc); 844 InitializationSequence InitSeq(*this, Entity, Kind, Exprs, NumExprs); 845 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, exprs); 846 847 if (!Result.isInvalid() && ListInitialization && 848 isa<InitListExpr>(Result.get())) { 849 // If the list-initialization doesn't involve a constructor call, we'll get 850 // the initializer-list (with corrected type) back, but that's not what we 851 // want, since it will be treated as an initializer list in further 852 // processing. Explicitly insert a cast here. 853 InitListExpr *List = cast<InitListExpr>(Result.take()); 854 Result = Owned(CXXFunctionalCastExpr::Create(Context, List->getType(), 855 Expr::getValueKindForType(TInfo->getType()), 856 TInfo, TyBeginLoc, CK_NoOp, 857 List, /*Path=*/0, RParenLoc)); 858 } 859 860 // FIXME: Improve AST representation? 861 return Result; 862 } 863 864 /// doesUsualArrayDeleteWantSize - Answers whether the usual 865 /// operator delete[] for the given type has a size_t parameter. 866 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc, 867 QualType allocType) { 868 const RecordType *record = 869 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>(); 870 if (!record) return false; 871 872 // Try to find an operator delete[] in class scope. 873 874 DeclarationName deleteName = 875 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete); 876 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName); 877 S.LookupQualifiedName(ops, record->getDecl()); 878 879 // We're just doing this for information. 880 ops.suppressDiagnostics(); 881 882 // Very likely: there's no operator delete[]. 883 if (ops.empty()) return false; 884 885 // If it's ambiguous, it should be illegal to call operator delete[] 886 // on this thing, so it doesn't matter if we allocate extra space or not. 887 if (ops.isAmbiguous()) return false; 888 889 LookupResult::Filter filter = ops.makeFilter(); 890 while (filter.hasNext()) { 891 NamedDecl *del = filter.next()->getUnderlyingDecl(); 892 893 // C++0x [basic.stc.dynamic.deallocation]p2: 894 // A template instance is never a usual deallocation function, 895 // regardless of its signature. 896 if (isa<FunctionTemplateDecl>(del)) { 897 filter.erase(); 898 continue; 899 } 900 901 // C++0x [basic.stc.dynamic.deallocation]p2: 902 // If class T does not declare [an operator delete[] with one 903 // parameter] but does declare a member deallocation function 904 // named operator delete[] with exactly two parameters, the 905 // second of which has type std::size_t, then this function 906 // is a usual deallocation function. 907 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) { 908 filter.erase(); 909 continue; 910 } 911 } 912 filter.done(); 913 914 if (!ops.isSingleResult()) return false; 915 916 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl()); 917 return (del->getNumParams() == 2); 918 } 919 920 /// \brief Parsed a C++ 'new' expression (C++ 5.3.4). 921 /// 922 /// E.g.: 923 /// @code new (memory) int[size][4] @endcode 924 /// or 925 /// @code ::new Foo(23, "hello") @endcode 926 /// 927 /// \param StartLoc The first location of the expression. 928 /// \param UseGlobal True if 'new' was prefixed with '::'. 929 /// \param PlacementLParen Opening paren of the placement arguments. 930 /// \param PlacementArgs Placement new arguments. 931 /// \param PlacementRParen Closing paren of the placement arguments. 932 /// \param TypeIdParens If the type is in parens, the source range. 933 /// \param D The type to be allocated, as well as array dimensions. 934 /// \param Initializer The initializing expression or initializer-list, or null 935 /// if there is none. 936 ExprResult 937 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal, 938 SourceLocation PlacementLParen, MultiExprArg PlacementArgs, 939 SourceLocation PlacementRParen, SourceRange TypeIdParens, 940 Declarator &D, Expr *Initializer) { 941 bool TypeContainsAuto = D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto; 942 943 Expr *ArraySize = 0; 944 // If the specified type is an array, unwrap it and save the expression. 945 if (D.getNumTypeObjects() > 0 && 946 D.getTypeObject(0).Kind == DeclaratorChunk::Array) { 947 DeclaratorChunk &Chunk = D.getTypeObject(0); 948 if (TypeContainsAuto) 949 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto) 950 << D.getSourceRange()); 951 if (Chunk.Arr.hasStatic) 952 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new) 953 << D.getSourceRange()); 954 if (!Chunk.Arr.NumElts) 955 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size) 956 << D.getSourceRange()); 957 958 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts); 959 D.DropFirstTypeObject(); 960 } 961 962 // Every dimension shall be of constant size. 963 if (ArraySize) { 964 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) { 965 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array) 966 break; 967 968 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr; 969 if (Expr *NumElts = (Expr *)Array.NumElts) { 970 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) { 971 Array.NumElts 972 = VerifyIntegerConstantExpression(NumElts, 0, 973 diag::err_new_array_nonconst) 974 .take(); 975 if (!Array.NumElts) 976 return ExprError(); 977 } 978 } 979 } 980 } 981 982 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/0); 983 QualType AllocType = TInfo->getType(); 984 if (D.isInvalidType()) 985 return ExprError(); 986 987 SourceRange DirectInitRange; 988 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) 989 DirectInitRange = List->getSourceRange(); 990 991 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal, 992 PlacementLParen, 993 PlacementArgs, 994 PlacementRParen, 995 TypeIdParens, 996 AllocType, 997 TInfo, 998 ArraySize, 999 DirectInitRange, 1000 Initializer, 1001 TypeContainsAuto); 1002 } 1003 1004 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style, 1005 Expr *Init) { 1006 if (!Init) 1007 return true; 1008 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init)) 1009 return PLE->getNumExprs() == 0; 1010 if (isa<ImplicitValueInitExpr>(Init)) 1011 return true; 1012 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) 1013 return !CCE->isListInitialization() && 1014 CCE->getConstructor()->isDefaultConstructor(); 1015 else if (Style == CXXNewExpr::ListInit) { 1016 assert(isa<InitListExpr>(Init) && 1017 "Shouldn't create list CXXConstructExprs for arrays."); 1018 return true; 1019 } 1020 return false; 1021 } 1022 1023 ExprResult 1024 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal, 1025 SourceLocation PlacementLParen, 1026 MultiExprArg PlacementArgs, 1027 SourceLocation PlacementRParen, 1028 SourceRange TypeIdParens, 1029 QualType AllocType, 1030 TypeSourceInfo *AllocTypeInfo, 1031 Expr *ArraySize, 1032 SourceRange DirectInitRange, 1033 Expr *Initializer, 1034 bool TypeMayContainAuto) { 1035 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange(); 1036 SourceLocation StartLoc = Range.getBegin(); 1037 1038 CXXNewExpr::InitializationStyle initStyle; 1039 if (DirectInitRange.isValid()) { 1040 assert(Initializer && "Have parens but no initializer."); 1041 initStyle = CXXNewExpr::CallInit; 1042 } else if (Initializer && isa<InitListExpr>(Initializer)) 1043 initStyle = CXXNewExpr::ListInit; 1044 else { 1045 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) || 1046 isa<CXXConstructExpr>(Initializer)) && 1047 "Initializer expression that cannot have been implicitly created."); 1048 initStyle = CXXNewExpr::NoInit; 1049 } 1050 1051 Expr **Inits = &Initializer; 1052 unsigned NumInits = Initializer ? 1 : 0; 1053 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) { 1054 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init"); 1055 Inits = List->getExprs(); 1056 NumInits = List->getNumExprs(); 1057 } 1058 1059 // Determine whether we've already built the initializer. 1060 bool HaveCompleteInit = false; 1061 if (Initializer && isa<CXXConstructExpr>(Initializer) && 1062 !isa<CXXTemporaryObjectExpr>(Initializer)) 1063 HaveCompleteInit = true; 1064 else if (Initializer && isa<ImplicitValueInitExpr>(Initializer)) 1065 HaveCompleteInit = true; 1066 1067 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 1068 AutoType *AT = 0; 1069 if (TypeMayContainAuto && 1070 (AT = AllocType->getContainedAutoType()) && !AT->isDeduced()) { 1071 if (initStyle == CXXNewExpr::NoInit || NumInits == 0) 1072 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg) 1073 << AllocType << TypeRange); 1074 if (initStyle == CXXNewExpr::ListInit) 1075 return ExprError(Diag(Inits[0]->getLocStart(), 1076 diag::err_auto_new_requires_parens) 1077 << AllocType << TypeRange); 1078 if (NumInits > 1) { 1079 Expr *FirstBad = Inits[1]; 1080 return ExprError(Diag(FirstBad->getLocStart(), 1081 diag::err_auto_new_ctor_multiple_expressions) 1082 << AllocType << TypeRange); 1083 } 1084 Expr *Deduce = Inits[0]; 1085 TypeSourceInfo *DeducedType = 0; 1086 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed) 1087 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure) 1088 << AllocType << Deduce->getType() 1089 << TypeRange << Deduce->getSourceRange()); 1090 if (!DeducedType) 1091 return ExprError(); 1092 1093 AllocTypeInfo = DeducedType; 1094 AllocType = AllocTypeInfo->getType(); 1095 } 1096 1097 // Per C++0x [expr.new]p5, the type being constructed may be a 1098 // typedef of an array type. 1099 if (!ArraySize) { 1100 if (const ConstantArrayType *Array 1101 = Context.getAsConstantArrayType(AllocType)) { 1102 ArraySize = IntegerLiteral::Create(Context, Array->getSize(), 1103 Context.getSizeType(), 1104 TypeRange.getEnd()); 1105 AllocType = Array->getElementType(); 1106 } 1107 } 1108 1109 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange)) 1110 return ExprError(); 1111 1112 if (initStyle == CXXNewExpr::ListInit && isStdInitializerList(AllocType, 0)) { 1113 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(), 1114 diag::warn_dangling_std_initializer_list) 1115 << /*at end of FE*/0 << Inits[0]->getSourceRange(); 1116 } 1117 1118 // In ARC, infer 'retaining' for the allocated 1119 if (getLangOpts().ObjCAutoRefCount && 1120 AllocType.getObjCLifetime() == Qualifiers::OCL_None && 1121 AllocType->isObjCLifetimeType()) { 1122 AllocType = Context.getLifetimeQualifiedType(AllocType, 1123 AllocType->getObjCARCImplicitLifetime()); 1124 } 1125 1126 QualType ResultType = Context.getPointerType(AllocType); 1127 1128 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have 1129 // integral or enumeration type with a non-negative value." 1130 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped 1131 // enumeration type, or a class type for which a single non-explicit 1132 // conversion function to integral or unscoped enumeration type exists. 1133 if (ArraySize && !ArraySize->isTypeDependent()) { 1134 class SizeConvertDiagnoser : public ICEConvertDiagnoser { 1135 Expr *ArraySize; 1136 1137 public: 1138 SizeConvertDiagnoser(Expr *ArraySize) 1139 : ICEConvertDiagnoser(false, false), ArraySize(ArraySize) { } 1140 1141 virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc, 1142 QualType T) { 1143 return S.Diag(Loc, diag::err_array_size_not_integral) 1144 << S.getLangOpts().CPlusPlus11 << T; 1145 } 1146 1147 virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc, 1148 QualType T) { 1149 return S.Diag(Loc, diag::err_array_size_incomplete_type) 1150 << T << ArraySize->getSourceRange(); 1151 } 1152 1153 virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, 1154 SourceLocation Loc, 1155 QualType T, 1156 QualType ConvTy) { 1157 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy; 1158 } 1159 1160 virtual DiagnosticBuilder noteExplicitConv(Sema &S, 1161 CXXConversionDecl *Conv, 1162 QualType ConvTy) { 1163 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion) 1164 << ConvTy->isEnumeralType() << ConvTy; 1165 } 1166 1167 virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc, 1168 QualType T) { 1169 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T; 1170 } 1171 1172 virtual DiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv, 1173 QualType ConvTy) { 1174 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion) 1175 << ConvTy->isEnumeralType() << ConvTy; 1176 } 1177 1178 virtual DiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc, 1179 QualType T, 1180 QualType ConvTy) { 1181 return S.Diag(Loc, 1182 S.getLangOpts().CPlusPlus11 1183 ? diag::warn_cxx98_compat_array_size_conversion 1184 : diag::ext_array_size_conversion) 1185 << T << ConvTy->isEnumeralType() << ConvTy; 1186 } 1187 } SizeDiagnoser(ArraySize); 1188 1189 ExprResult ConvertedSize 1190 = ConvertToIntegralOrEnumerationType(StartLoc, ArraySize, SizeDiagnoser, 1191 /*AllowScopedEnumerations*/ false); 1192 if (ConvertedSize.isInvalid()) 1193 return ExprError(); 1194 1195 ArraySize = ConvertedSize.take(); 1196 QualType SizeType = ArraySize->getType(); 1197 if (!SizeType->isIntegralOrUnscopedEnumerationType()) 1198 return ExprError(); 1199 1200 // C++98 [expr.new]p7: 1201 // The expression in a direct-new-declarator shall have integral type 1202 // with a non-negative value. 1203 // 1204 // Let's see if this is a constant < 0. If so, we reject it out of 1205 // hand. Otherwise, if it's not a constant, we must have an unparenthesized 1206 // array type. 1207 // 1208 // Note: such a construct has well-defined semantics in C++11: it throws 1209 // std::bad_array_new_length. 1210 if (!ArraySize->isValueDependent()) { 1211 llvm::APSInt Value; 1212 // We've already performed any required implicit conversion to integer or 1213 // unscoped enumeration type. 1214 if (ArraySize->isIntegerConstantExpr(Value, Context)) { 1215 if (Value < llvm::APSInt( 1216 llvm::APInt::getNullValue(Value.getBitWidth()), 1217 Value.isUnsigned())) { 1218 if (getLangOpts().CPlusPlus11) 1219 Diag(ArraySize->getLocStart(), 1220 diag::warn_typecheck_negative_array_new_size) 1221 << ArraySize->getSourceRange(); 1222 else 1223 return ExprError(Diag(ArraySize->getLocStart(), 1224 diag::err_typecheck_negative_array_size) 1225 << ArraySize->getSourceRange()); 1226 } else if (!AllocType->isDependentType()) { 1227 unsigned ActiveSizeBits = 1228 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value); 1229 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 1230 if (getLangOpts().CPlusPlus11) 1231 Diag(ArraySize->getLocStart(), 1232 diag::warn_array_new_too_large) 1233 << Value.toString(10) 1234 << ArraySize->getSourceRange(); 1235 else 1236 return ExprError(Diag(ArraySize->getLocStart(), 1237 diag::err_array_too_large) 1238 << Value.toString(10) 1239 << ArraySize->getSourceRange()); 1240 } 1241 } 1242 } else if (TypeIdParens.isValid()) { 1243 // Can't have dynamic array size when the type-id is in parentheses. 1244 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst) 1245 << ArraySize->getSourceRange() 1246 << FixItHint::CreateRemoval(TypeIdParens.getBegin()) 1247 << FixItHint::CreateRemoval(TypeIdParens.getEnd()); 1248 1249 TypeIdParens = SourceRange(); 1250 } 1251 } 1252 1253 // Note that we do *not* convert the argument in any way. It can 1254 // be signed, larger than size_t, whatever. 1255 } 1256 1257 FunctionDecl *OperatorNew = 0; 1258 FunctionDecl *OperatorDelete = 0; 1259 Expr **PlaceArgs = PlacementArgs.data(); 1260 unsigned NumPlaceArgs = PlacementArgs.size(); 1261 1262 if (!AllocType->isDependentType() && 1263 !Expr::hasAnyTypeDependentArguments( 1264 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs)) && 1265 FindAllocationFunctions(StartLoc, 1266 SourceRange(PlacementLParen, PlacementRParen), 1267 UseGlobal, AllocType, ArraySize, PlaceArgs, 1268 NumPlaceArgs, OperatorNew, OperatorDelete)) 1269 return ExprError(); 1270 1271 // If this is an array allocation, compute whether the usual array 1272 // deallocation function for the type has a size_t parameter. 1273 bool UsualArrayDeleteWantsSize = false; 1274 if (ArraySize && !AllocType->isDependentType()) 1275 UsualArrayDeleteWantsSize 1276 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType); 1277 1278 SmallVector<Expr *, 8> AllPlaceArgs; 1279 if (OperatorNew) { 1280 // Add default arguments, if any. 1281 const FunctionProtoType *Proto = 1282 OperatorNew->getType()->getAs<FunctionProtoType>(); 1283 VariadicCallType CallType = 1284 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 1285 1286 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, 1287 Proto, 1, PlaceArgs, NumPlaceArgs, 1288 AllPlaceArgs, CallType)) 1289 return ExprError(); 1290 1291 NumPlaceArgs = AllPlaceArgs.size(); 1292 if (NumPlaceArgs > 0) 1293 PlaceArgs = &AllPlaceArgs[0]; 1294 1295 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, 1296 PlaceArgs, NumPlaceArgs); 1297 1298 // FIXME: Missing call to CheckFunctionCall or equivalent 1299 } 1300 1301 // Warn if the type is over-aligned and is being allocated by global operator 1302 // new. 1303 if (NumPlaceArgs == 0 && OperatorNew && 1304 (OperatorNew->isImplicit() || 1305 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1306 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1307 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1308 if (Align > SuitableAlign) 1309 Diag(StartLoc, diag::warn_overaligned_type) 1310 << AllocType 1311 << unsigned(Align / Context.getCharWidth()) 1312 << unsigned(SuitableAlign / Context.getCharWidth()); 1313 } 1314 } 1315 1316 QualType InitType = AllocType; 1317 // Array 'new' can't have any initializers except empty parentheses. 1318 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1319 // dialect distinction. 1320 if (ResultType->isArrayType() || ArraySize) { 1321 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1322 SourceRange InitRange(Inits[0]->getLocStart(), 1323 Inits[NumInits - 1]->getLocEnd()); 1324 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1325 return ExprError(); 1326 } 1327 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1328 // We do the initialization typechecking against the array type 1329 // corresponding to the number of initializers + 1 (to also check 1330 // default-initialization). 1331 unsigned NumElements = ILE->getNumInits() + 1; 1332 InitType = Context.getConstantArrayType(AllocType, 1333 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1334 ArrayType::Normal, 0); 1335 } 1336 } 1337 1338 // If we can perform the initialization, and we've not already done so, 1339 // do it now. 1340 if (!AllocType->isDependentType() && 1341 !Expr::hasAnyTypeDependentArguments( 1342 llvm::makeArrayRef(Inits, NumInits)) && 1343 !HaveCompleteInit) { 1344 // C++11 [expr.new]p15: 1345 // A new-expression that creates an object of type T initializes that 1346 // object as follows: 1347 InitializationKind Kind 1348 // - If the new-initializer is omitted, the object is default- 1349 // initialized (8.5); if no initialization is performed, 1350 // the object has indeterminate value 1351 = initStyle == CXXNewExpr::NoInit 1352 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1353 // - Otherwise, the new-initializer is interpreted according to the 1354 // initialization rules of 8.5 for direct-initialization. 1355 : initStyle == CXXNewExpr::ListInit 1356 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1357 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1358 DirectInitRange.getBegin(), 1359 DirectInitRange.getEnd()); 1360 1361 InitializedEntity Entity 1362 = InitializedEntity::InitializeNew(StartLoc, InitType); 1363 InitializationSequence InitSeq(*this, Entity, Kind, Inits, NumInits); 1364 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1365 MultiExprArg(Inits, NumInits)); 1366 if (FullInit.isInvalid()) 1367 return ExprError(); 1368 1369 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1370 // we don't want the initialized object to be destructed. 1371 if (CXXBindTemporaryExpr *Binder = 1372 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1373 FullInit = Owned(Binder->getSubExpr()); 1374 1375 Initializer = FullInit.take(); 1376 } 1377 1378 // Mark the new and delete operators as referenced. 1379 if (OperatorNew) { 1380 DiagnoseUseOfDecl(OperatorNew, StartLoc); 1381 MarkFunctionReferenced(StartLoc, OperatorNew); 1382 } 1383 if (OperatorDelete) { 1384 DiagnoseUseOfDecl(OperatorDelete, StartLoc); 1385 MarkFunctionReferenced(StartLoc, OperatorDelete); 1386 } 1387 1388 // C++0x [expr.new]p17: 1389 // If the new expression creates an array of objects of class type, 1390 // access and ambiguity control are done for the destructor. 1391 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1392 if (ArraySize && !BaseAllocType->isDependentType()) { 1393 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) { 1394 if (CXXDestructorDecl *dtor = LookupDestructor( 1395 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) { 1396 MarkFunctionReferenced(StartLoc, dtor); 1397 CheckDestructorAccess(StartLoc, dtor, 1398 PDiag(diag::err_access_dtor) 1399 << BaseAllocType); 1400 DiagnoseUseOfDecl(dtor, StartLoc); 1401 } 1402 } 1403 } 1404 1405 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1406 OperatorDelete, 1407 UsualArrayDeleteWantsSize, 1408 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs), 1409 TypeIdParens, 1410 ArraySize, initStyle, Initializer, 1411 ResultType, AllocTypeInfo, 1412 Range, DirectInitRange)); 1413 } 1414 1415 /// \brief Checks that a type is suitable as the allocated type 1416 /// in a new-expression. 1417 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1418 SourceRange R) { 1419 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1420 // abstract class type or array thereof. 1421 if (AllocType->isFunctionType()) 1422 return Diag(Loc, diag::err_bad_new_type) 1423 << AllocType << 0 << R; 1424 else if (AllocType->isReferenceType()) 1425 return Diag(Loc, diag::err_bad_new_type) 1426 << AllocType << 1 << R; 1427 else if (!AllocType->isDependentType() && 1428 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R)) 1429 return true; 1430 else if (RequireNonAbstractType(Loc, AllocType, 1431 diag::err_allocation_of_abstract_type)) 1432 return true; 1433 else if (AllocType->isVariablyModifiedType()) 1434 return Diag(Loc, diag::err_variably_modified_new_type) 1435 << AllocType; 1436 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1437 return Diag(Loc, diag::err_address_space_qualified_new) 1438 << AllocType.getUnqualifiedType() << AddressSpace; 1439 else if (getLangOpts().ObjCAutoRefCount) { 1440 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1441 QualType BaseAllocType = Context.getBaseElementType(AT); 1442 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1443 BaseAllocType->isObjCLifetimeType()) 1444 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1445 << BaseAllocType; 1446 } 1447 } 1448 1449 return false; 1450 } 1451 1452 /// \brief Determine whether the given function is a non-placement 1453 /// deallocation function. 1454 static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1455 if (FD->isInvalidDecl()) 1456 return false; 1457 1458 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1459 return Method->isUsualDeallocationFunction(); 1460 1461 return ((FD->getOverloadedOperator() == OO_Delete || 1462 FD->getOverloadedOperator() == OO_Array_Delete) && 1463 FD->getNumParams() == 1); 1464 } 1465 1466 /// FindAllocationFunctions - Finds the overloads of operator new and delete 1467 /// that are appropriate for the allocation. 1468 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1469 bool UseGlobal, QualType AllocType, 1470 bool IsArray, Expr **PlaceArgs, 1471 unsigned NumPlaceArgs, 1472 FunctionDecl *&OperatorNew, 1473 FunctionDecl *&OperatorDelete) { 1474 // --- Choosing an allocation function --- 1475 // C++ 5.3.4p8 - 14 & 18 1476 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1477 // in the scope of the allocated class. 1478 // 2) If an array size is given, look for operator new[], else look for 1479 // operator new. 1480 // 3) The first argument is always size_t. Append the arguments from the 1481 // placement form. 1482 1483 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1484 // We don't care about the actual value of this argument. 1485 // FIXME: Should the Sema create the expression and embed it in the syntax 1486 // tree? Or should the consumer just recalculate the value? 1487 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1488 Context.getTargetInfo().getPointerWidth(0)), 1489 Context.getSizeType(), 1490 SourceLocation()); 1491 AllocArgs[0] = &Size; 1492 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1493 1494 // C++ [expr.new]p8: 1495 // If the allocated type is a non-array type, the allocation 1496 // function's name is operator new and the deallocation function's 1497 // name is operator delete. If the allocated type is an array 1498 // type, the allocation function's name is operator new[] and the 1499 // deallocation function's name is operator delete[]. 1500 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1501 IsArray ? OO_Array_New : OO_New); 1502 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1503 IsArray ? OO_Array_Delete : OO_Delete); 1504 1505 QualType AllocElemType = Context.getBaseElementType(AllocType); 1506 1507 if (AllocElemType->isRecordType() && !UseGlobal) { 1508 CXXRecordDecl *Record 1509 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1510 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1511 AllocArgs.size(), Record, /*AllowMissing=*/true, 1512 OperatorNew)) 1513 return true; 1514 } 1515 if (!OperatorNew) { 1516 // Didn't find a member overload. Look for a global one. 1517 DeclareGlobalNewDelete(); 1518 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1519 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1520 AllocArgs.size(), TUDecl, /*AllowMissing=*/false, 1521 OperatorNew)) 1522 return true; 1523 } 1524 1525 // We don't need an operator delete if we're running under 1526 // -fno-exceptions. 1527 if (!getLangOpts().Exceptions) { 1528 OperatorDelete = 0; 1529 return false; 1530 } 1531 1532 // FindAllocationOverload can change the passed in arguments, so we need to 1533 // copy them back. 1534 if (NumPlaceArgs > 0) 1535 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1536 1537 // C++ [expr.new]p19: 1538 // 1539 // If the new-expression begins with a unary :: operator, the 1540 // deallocation function's name is looked up in the global 1541 // scope. Otherwise, if the allocated type is a class type T or an 1542 // array thereof, the deallocation function's name is looked up in 1543 // the scope of T. If this lookup fails to find the name, or if 1544 // the allocated type is not a class type or array thereof, the 1545 // deallocation function's name is looked up in the global scope. 1546 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1547 if (AllocElemType->isRecordType() && !UseGlobal) { 1548 CXXRecordDecl *RD 1549 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1550 LookupQualifiedName(FoundDelete, RD); 1551 } 1552 if (FoundDelete.isAmbiguous()) 1553 return true; // FIXME: clean up expressions? 1554 1555 if (FoundDelete.empty()) { 1556 DeclareGlobalNewDelete(); 1557 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1558 } 1559 1560 FoundDelete.suppressDiagnostics(); 1561 1562 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1563 1564 // Whether we're looking for a placement operator delete is dictated 1565 // by whether we selected a placement operator new, not by whether 1566 // we had explicit placement arguments. This matters for things like 1567 // struct A { void *operator new(size_t, int = 0); ... }; 1568 // A *a = new A() 1569 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1570 1571 if (isPlacementNew) { 1572 // C++ [expr.new]p20: 1573 // A declaration of a placement deallocation function matches the 1574 // declaration of a placement allocation function if it has the 1575 // same number of parameters and, after parameter transformations 1576 // (8.3.5), all parameter types except the first are 1577 // identical. [...] 1578 // 1579 // To perform this comparison, we compute the function type that 1580 // the deallocation function should have, and use that type both 1581 // for template argument deduction and for comparison purposes. 1582 // 1583 // FIXME: this comparison should ignore CC and the like. 1584 QualType ExpectedFunctionType; 1585 { 1586 const FunctionProtoType *Proto 1587 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1588 1589 SmallVector<QualType, 4> ArgTypes; 1590 ArgTypes.push_back(Context.VoidPtrTy); 1591 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1592 ArgTypes.push_back(Proto->getArgType(I)); 1593 1594 FunctionProtoType::ExtProtoInfo EPI; 1595 EPI.Variadic = Proto->isVariadic(); 1596 1597 ExpectedFunctionType 1598 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI); 1599 } 1600 1601 for (LookupResult::iterator D = FoundDelete.begin(), 1602 DEnd = FoundDelete.end(); 1603 D != DEnd; ++D) { 1604 FunctionDecl *Fn = 0; 1605 if (FunctionTemplateDecl *FnTmpl 1606 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1607 // Perform template argument deduction to try to match the 1608 // expected function type. 1609 TemplateDeductionInfo Info(StartLoc); 1610 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1611 continue; 1612 } else 1613 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1614 1615 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1616 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1617 } 1618 } else { 1619 // C++ [expr.new]p20: 1620 // [...] Any non-placement deallocation function matches a 1621 // non-placement allocation function. [...] 1622 for (LookupResult::iterator D = FoundDelete.begin(), 1623 DEnd = FoundDelete.end(); 1624 D != DEnd; ++D) { 1625 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1626 if (isNonPlacementDeallocationFunction(Fn)) 1627 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1628 } 1629 } 1630 1631 // C++ [expr.new]p20: 1632 // [...] If the lookup finds a single matching deallocation 1633 // function, that function will be called; otherwise, no 1634 // deallocation function will be called. 1635 if (Matches.size() == 1) { 1636 OperatorDelete = Matches[0].second; 1637 1638 // C++0x [expr.new]p20: 1639 // If the lookup finds the two-parameter form of a usual 1640 // deallocation function (3.7.4.2) and that function, considered 1641 // as a placement deallocation function, would have been 1642 // selected as a match for the allocation function, the program 1643 // is ill-formed. 1644 if (NumPlaceArgs && getLangOpts().CPlusPlus11 && 1645 isNonPlacementDeallocationFunction(OperatorDelete)) { 1646 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1647 << SourceRange(PlaceArgs[0]->getLocStart(), 1648 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1649 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1650 << DeleteName; 1651 } else { 1652 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1653 Matches[0].first); 1654 } 1655 } 1656 1657 return false; 1658 } 1659 1660 /// FindAllocationOverload - Find an fitting overload for the allocation 1661 /// function in the specified scope. 1662 bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1663 DeclarationName Name, Expr** Args, 1664 unsigned NumArgs, DeclContext *Ctx, 1665 bool AllowMissing, FunctionDecl *&Operator, 1666 bool Diagnose) { 1667 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1668 LookupQualifiedName(R, Ctx); 1669 if (R.empty()) { 1670 if (AllowMissing || !Diagnose) 1671 return false; 1672 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1673 << Name << Range; 1674 } 1675 1676 if (R.isAmbiguous()) 1677 return true; 1678 1679 R.suppressDiagnostics(); 1680 1681 OverloadCandidateSet Candidates(StartLoc); 1682 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1683 Alloc != AllocEnd; ++Alloc) { 1684 // Even member operator new/delete are implicitly treated as 1685 // static, so don't use AddMemberCandidate. 1686 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1687 1688 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1689 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1690 /*ExplicitTemplateArgs=*/0, 1691 llvm::makeArrayRef(Args, NumArgs), 1692 Candidates, 1693 /*SuppressUserConversions=*/false); 1694 continue; 1695 } 1696 1697 FunctionDecl *Fn = cast<FunctionDecl>(D); 1698 AddOverloadCandidate(Fn, Alloc.getPair(), 1699 llvm::makeArrayRef(Args, NumArgs), Candidates, 1700 /*SuppressUserConversions=*/false); 1701 } 1702 1703 // Do the resolution. 1704 OverloadCandidateSet::iterator Best; 1705 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1706 case OR_Success: { 1707 // Got one! 1708 FunctionDecl *FnDecl = Best->Function; 1709 MarkFunctionReferenced(StartLoc, FnDecl); 1710 // The first argument is size_t, and the first parameter must be size_t, 1711 // too. This is checked on declaration and can be assumed. (It can't be 1712 // asserted on, though, since invalid decls are left in there.) 1713 // Watch out for variadic allocator function. 1714 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1715 for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) { 1716 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1717 FnDecl->getParamDecl(i)); 1718 1719 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1720 return true; 1721 1722 ExprResult Result 1723 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1724 if (Result.isInvalid()) 1725 return true; 1726 1727 Args[i] = Result.takeAs<Expr>(); 1728 } 1729 1730 Operator = FnDecl; 1731 1732 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), 1733 Best->FoundDecl, Diagnose) == AR_inaccessible) 1734 return true; 1735 1736 return false; 1737 } 1738 1739 case OR_No_Viable_Function: 1740 if (Diagnose) { 1741 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1742 << Name << Range; 1743 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1744 llvm::makeArrayRef(Args, NumArgs)); 1745 } 1746 return true; 1747 1748 case OR_Ambiguous: 1749 if (Diagnose) { 1750 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1751 << Name << Range; 1752 Candidates.NoteCandidates(*this, OCD_ViableCandidates, 1753 llvm::makeArrayRef(Args, NumArgs)); 1754 } 1755 return true; 1756 1757 case OR_Deleted: { 1758 if (Diagnose) { 1759 Diag(StartLoc, diag::err_ovl_deleted_call) 1760 << Best->Function->isDeleted() 1761 << Name 1762 << getDeletedOrUnavailableSuffix(Best->Function) 1763 << Range; 1764 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1765 llvm::makeArrayRef(Args, NumArgs)); 1766 } 1767 return true; 1768 } 1769 } 1770 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1771 } 1772 1773 1774 /// DeclareGlobalNewDelete - Declare the global forms of operator new and 1775 /// delete. These are: 1776 /// @code 1777 /// // C++03: 1778 /// void* operator new(std::size_t) throw(std::bad_alloc); 1779 /// void* operator new[](std::size_t) throw(std::bad_alloc); 1780 /// void operator delete(void *) throw(); 1781 /// void operator delete[](void *) throw(); 1782 /// // C++0x: 1783 /// void* operator new(std::size_t); 1784 /// void* operator new[](std::size_t); 1785 /// void operator delete(void *); 1786 /// void operator delete[](void *); 1787 /// @endcode 1788 /// C++0x operator delete is implicitly noexcept. 1789 /// Note that the placement and nothrow forms of new are *not* implicitly 1790 /// declared. Their use requires including \<new\>. 1791 void Sema::DeclareGlobalNewDelete() { 1792 if (GlobalNewDeleteDeclared) 1793 return; 1794 1795 // C++ [basic.std.dynamic]p2: 1796 // [...] The following allocation and deallocation functions (18.4) are 1797 // implicitly declared in global scope in each translation unit of a 1798 // program 1799 // 1800 // C++03: 1801 // void* operator new(std::size_t) throw(std::bad_alloc); 1802 // void* operator new[](std::size_t) throw(std::bad_alloc); 1803 // void operator delete(void*) throw(); 1804 // void operator delete[](void*) throw(); 1805 // C++0x: 1806 // void* operator new(std::size_t); 1807 // void* operator new[](std::size_t); 1808 // void operator delete(void*); 1809 // void operator delete[](void*); 1810 // 1811 // These implicit declarations introduce only the function names operator 1812 // new, operator new[], operator delete, operator delete[]. 1813 // 1814 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1815 // "std" or "bad_alloc" as necessary to form the exception specification. 1816 // However, we do not make these implicit declarations visible to name 1817 // lookup. 1818 // Note that the C++0x versions of operator delete are deallocation functions, 1819 // and thus are implicitly noexcept. 1820 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) { 1821 // The "std::bad_alloc" class has not yet been declared, so build it 1822 // implicitly. 1823 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1824 getOrCreateStdNamespace(), 1825 SourceLocation(), SourceLocation(), 1826 &PP.getIdentifierTable().get("bad_alloc"), 1827 0); 1828 getStdBadAlloc()->setImplicit(true); 1829 } 1830 1831 GlobalNewDeleteDeclared = true; 1832 1833 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1834 QualType SizeT = Context.getSizeType(); 1835 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew; 1836 1837 DeclareGlobalAllocationFunction( 1838 Context.DeclarationNames.getCXXOperatorName(OO_New), 1839 VoidPtr, SizeT, AssumeSaneOperatorNew); 1840 DeclareGlobalAllocationFunction( 1841 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1842 VoidPtr, SizeT, AssumeSaneOperatorNew); 1843 DeclareGlobalAllocationFunction( 1844 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1845 Context.VoidTy, VoidPtr); 1846 DeclareGlobalAllocationFunction( 1847 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1848 Context.VoidTy, VoidPtr); 1849 } 1850 1851 /// DeclareGlobalAllocationFunction - Declares a single implicit global 1852 /// allocation function if it doesn't already exist. 1853 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1854 QualType Return, QualType Argument, 1855 bool AddMallocAttr) { 1856 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1857 1858 // Check if this function is already declared. 1859 { 1860 DeclContext::lookup_result R = GlobalCtx->lookup(Name); 1861 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end(); 1862 Alloc != AllocEnd; ++Alloc) { 1863 // Only look at non-template functions, as it is the predefined, 1864 // non-templated allocation function we are trying to declare here. 1865 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1866 QualType InitialParamType = 1867 Context.getCanonicalType( 1868 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1869 // FIXME: Do we need to check for default arguments here? 1870 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1871 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1872 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1873 return; 1874 } 1875 } 1876 } 1877 } 1878 1879 QualType BadAllocType; 1880 bool HasBadAllocExceptionSpec 1881 = (Name.getCXXOverloadedOperator() == OO_New || 1882 Name.getCXXOverloadedOperator() == OO_Array_New); 1883 if (HasBadAllocExceptionSpec && !getLangOpts().CPlusPlus11) { 1884 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1885 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1886 } 1887 1888 FunctionProtoType::ExtProtoInfo EPI; 1889 if (HasBadAllocExceptionSpec) { 1890 if (!getLangOpts().CPlusPlus11) { 1891 EPI.ExceptionSpecType = EST_Dynamic; 1892 EPI.NumExceptions = 1; 1893 EPI.Exceptions = &BadAllocType; 1894 } 1895 } else { 1896 EPI.ExceptionSpecType = getLangOpts().CPlusPlus11 ? 1897 EST_BasicNoexcept : EST_DynamicNone; 1898 } 1899 1900 QualType FnType = Context.getFunctionType(Return, Argument, EPI); 1901 FunctionDecl *Alloc = 1902 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1903 SourceLocation(), Name, 1904 FnType, /*TInfo=*/0, SC_None, 1905 SC_None, false, true); 1906 Alloc->setImplicit(); 1907 1908 if (AddMallocAttr) 1909 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1910 1911 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1912 SourceLocation(), 0, 1913 Argument, /*TInfo=*/0, 1914 SC_None, SC_None, 0); 1915 Alloc->setParams(Param); 1916 1917 // FIXME: Also add this declaration to the IdentifierResolver, but 1918 // make sure it is at the end of the chain to coincide with the 1919 // global scope. 1920 Context.getTranslationUnitDecl()->addDecl(Alloc); 1921 } 1922 1923 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1924 DeclarationName Name, 1925 FunctionDecl* &Operator, bool Diagnose) { 1926 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1927 // Try to find operator delete/operator delete[] in class scope. 1928 LookupQualifiedName(Found, RD); 1929 1930 if (Found.isAmbiguous()) 1931 return true; 1932 1933 Found.suppressDiagnostics(); 1934 1935 SmallVector<DeclAccessPair,4> Matches; 1936 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1937 F != FEnd; ++F) { 1938 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1939 1940 // Ignore template operator delete members from the check for a usual 1941 // deallocation function. 1942 if (isa<FunctionTemplateDecl>(ND)) 1943 continue; 1944 1945 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1946 Matches.push_back(F.getPair()); 1947 } 1948 1949 // There's exactly one suitable operator; pick it. 1950 if (Matches.size() == 1) { 1951 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 1952 1953 if (Operator->isDeleted()) { 1954 if (Diagnose) { 1955 Diag(StartLoc, diag::err_deleted_function_use); 1956 NoteDeletedFunction(Operator); 1957 } 1958 return true; 1959 } 1960 1961 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 1962 Matches[0], Diagnose) == AR_inaccessible) 1963 return true; 1964 1965 return false; 1966 1967 // We found multiple suitable operators; complain about the ambiguity. 1968 } else if (!Matches.empty()) { 1969 if (Diagnose) { 1970 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 1971 << Name << RD; 1972 1973 for (SmallVectorImpl<DeclAccessPair>::iterator 1974 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 1975 Diag((*F)->getUnderlyingDecl()->getLocation(), 1976 diag::note_member_declared_here) << Name; 1977 } 1978 return true; 1979 } 1980 1981 // We did find operator delete/operator delete[] declarations, but 1982 // none of them were suitable. 1983 if (!Found.empty()) { 1984 if (Diagnose) { 1985 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 1986 << Name << RD; 1987 1988 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1989 F != FEnd; ++F) 1990 Diag((*F)->getUnderlyingDecl()->getLocation(), 1991 diag::note_member_declared_here) << Name; 1992 } 1993 return true; 1994 } 1995 1996 // Look for a global declaration. 1997 DeclareGlobalNewDelete(); 1998 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1999 2000 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 2001 Expr* DeallocArgs[1]; 2002 DeallocArgs[0] = &Null; 2003 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 2004 DeallocArgs, 1, TUDecl, !Diagnose, 2005 Operator, Diagnose)) 2006 return true; 2007 2008 assert(Operator && "Did not find a deallocation function!"); 2009 return false; 2010 } 2011 2012 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 2013 /// @code ::delete ptr; @endcode 2014 /// or 2015 /// @code delete [] ptr; @endcode 2016 ExprResult 2017 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 2018 bool ArrayForm, Expr *ExE) { 2019 // C++ [expr.delete]p1: 2020 // The operand shall have a pointer type, or a class type having a single 2021 // conversion function to a pointer type. The result has type void. 2022 // 2023 // DR599 amends "pointer type" to "pointer to object type" in both cases. 2024 2025 ExprResult Ex = Owned(ExE); 2026 FunctionDecl *OperatorDelete = 0; 2027 bool ArrayFormAsWritten = ArrayForm; 2028 bool UsualArrayDeleteWantsSize = false; 2029 2030 if (!Ex.get()->isTypeDependent()) { 2031 // Perform lvalue-to-rvalue cast, if needed. 2032 Ex = DefaultLvalueConversion(Ex.take()); 2033 if (Ex.isInvalid()) 2034 return ExprError(); 2035 2036 QualType Type = Ex.get()->getType(); 2037 2038 if (const RecordType *Record = Type->getAs<RecordType>()) { 2039 if (RequireCompleteType(StartLoc, Type, 2040 diag::err_delete_incomplete_class_type)) 2041 return ExprError(); 2042 2043 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 2044 2045 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 2046 std::pair<CXXRecordDecl::conversion_iterator, 2047 CXXRecordDecl::conversion_iterator> 2048 Conversions = RD->getVisibleConversionFunctions(); 2049 for (CXXRecordDecl::conversion_iterator 2050 I = Conversions.first, E = Conversions.second; I != E; ++I) { 2051 NamedDecl *D = I.getDecl(); 2052 if (isa<UsingShadowDecl>(D)) 2053 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2054 2055 // Skip over templated conversion functions; they aren't considered. 2056 if (isa<FunctionTemplateDecl>(D)) 2057 continue; 2058 2059 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 2060 2061 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 2062 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 2063 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 2064 ObjectPtrConversions.push_back(Conv); 2065 } 2066 if (ObjectPtrConversions.size() == 1) { 2067 // We have a single conversion to a pointer-to-object type. Perform 2068 // that conversion. 2069 // TODO: don't redo the conversion calculation. 2070 ExprResult Res = 2071 PerformImplicitConversion(Ex.get(), 2072 ObjectPtrConversions.front()->getConversionType(), 2073 AA_Converting); 2074 if (Res.isUsable()) { 2075 Ex = Res; 2076 Type = Ex.get()->getType(); 2077 } 2078 } 2079 else if (ObjectPtrConversions.size() > 1) { 2080 Diag(StartLoc, diag::err_ambiguous_delete_operand) 2081 << Type << Ex.get()->getSourceRange(); 2082 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 2083 NoteOverloadCandidate(ObjectPtrConversions[i]); 2084 return ExprError(); 2085 } 2086 } 2087 2088 if (!Type->isPointerType()) 2089 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2090 << Type << Ex.get()->getSourceRange()); 2091 2092 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2093 QualType PointeeElem = Context.getBaseElementType(Pointee); 2094 2095 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2096 return Diag(Ex.get()->getLocStart(), 2097 diag::err_address_space_qualified_delete) 2098 << Pointee.getUnqualifiedType() << AddressSpace; 2099 2100 CXXRecordDecl *PointeeRD = 0; 2101 if (Pointee->isVoidType() && !isSFINAEContext()) { 2102 // The C++ standard bans deleting a pointer to a non-object type, which 2103 // effectively bans deletion of "void*". However, most compilers support 2104 // this, so we treat it as a warning unless we're in a SFINAE context. 2105 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2106 << Type << Ex.get()->getSourceRange(); 2107 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2108 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2109 << Type << Ex.get()->getSourceRange()); 2110 } else if (!Pointee->isDependentType()) { 2111 if (!RequireCompleteType(StartLoc, Pointee, 2112 diag::warn_delete_incomplete, Ex.get())) { 2113 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2114 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2115 } 2116 } 2117 2118 // C++ [expr.delete]p2: 2119 // [Note: a pointer to a const type can be the operand of a 2120 // delete-expression; it is not necessary to cast away the constness 2121 // (5.2.11) of the pointer expression before it is used as the operand 2122 // of the delete-expression. ] 2123 2124 if (Pointee->isArrayType() && !ArrayForm) { 2125 Diag(StartLoc, diag::warn_delete_array_type) 2126 << Type << Ex.get()->getSourceRange() 2127 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2128 ArrayForm = true; 2129 } 2130 2131 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2132 ArrayForm ? OO_Array_Delete : OO_Delete); 2133 2134 if (PointeeRD) { 2135 if (!UseGlobal && 2136 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2137 OperatorDelete)) 2138 return ExprError(); 2139 2140 // If we're allocating an array of records, check whether the 2141 // usual operator delete[] has a size_t parameter. 2142 if (ArrayForm) { 2143 // If the user specifically asked to use the global allocator, 2144 // we'll need to do the lookup into the class. 2145 if (UseGlobal) 2146 UsualArrayDeleteWantsSize = 2147 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2148 2149 // Otherwise, the usual operator delete[] should be the 2150 // function we just found. 2151 else if (isa<CXXMethodDecl>(OperatorDelete)) 2152 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2153 } 2154 2155 if (!PointeeRD->hasIrrelevantDestructor()) 2156 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2157 MarkFunctionReferenced(StartLoc, 2158 const_cast<CXXDestructorDecl*>(Dtor)); 2159 DiagnoseUseOfDecl(Dtor, StartLoc); 2160 } 2161 2162 // C++ [expr.delete]p3: 2163 // In the first alternative (delete object), if the static type of the 2164 // object to be deleted is different from its dynamic type, the static 2165 // type shall be a base class of the dynamic type of the object to be 2166 // deleted and the static type shall have a virtual destructor or the 2167 // behavior is undefined. 2168 // 2169 // Note: a final class cannot be derived from, no issue there 2170 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2171 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2172 if (dtor && !dtor->isVirtual()) { 2173 if (PointeeRD->isAbstract()) { 2174 // If the class is abstract, we warn by default, because we're 2175 // sure the code has undefined behavior. 2176 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2177 << PointeeElem; 2178 } else if (!ArrayForm) { 2179 // Otherwise, if this is not an array delete, it's a bit suspect, 2180 // but not necessarily wrong. 2181 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2182 } 2183 } 2184 } 2185 2186 } 2187 2188 if (!OperatorDelete) { 2189 // Look for a global declaration. 2190 DeclareGlobalNewDelete(); 2191 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2192 Expr *Arg = Ex.get(); 2193 if (!Context.hasSameType(Arg->getType(), Context.VoidPtrTy)) 2194 Arg = ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2195 CK_BitCast, Arg, 0, VK_RValue); 2196 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2197 &Arg, 1, TUDecl, /*AllowMissing=*/false, 2198 OperatorDelete)) 2199 return ExprError(); 2200 } 2201 2202 MarkFunctionReferenced(StartLoc, OperatorDelete); 2203 2204 // Check access and ambiguity of operator delete and destructor. 2205 if (PointeeRD) { 2206 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2207 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2208 PDiag(diag::err_access_dtor) << PointeeElem); 2209 } 2210 } 2211 2212 } 2213 2214 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2215 ArrayFormAsWritten, 2216 UsualArrayDeleteWantsSize, 2217 OperatorDelete, Ex.take(), StartLoc)); 2218 } 2219 2220 /// \brief Check the use of the given variable as a C++ condition in an if, 2221 /// while, do-while, or switch statement. 2222 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2223 SourceLocation StmtLoc, 2224 bool ConvertToBoolean) { 2225 QualType T = ConditionVar->getType(); 2226 2227 // C++ [stmt.select]p2: 2228 // The declarator shall not specify a function or an array. 2229 if (T->isFunctionType()) 2230 return ExprError(Diag(ConditionVar->getLocation(), 2231 diag::err_invalid_use_of_function_type) 2232 << ConditionVar->getSourceRange()); 2233 else if (T->isArrayType()) 2234 return ExprError(Diag(ConditionVar->getLocation(), 2235 diag::err_invalid_use_of_array_type) 2236 << ConditionVar->getSourceRange()); 2237 2238 ExprResult Condition = 2239 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2240 SourceLocation(), 2241 ConditionVar, 2242 /*enclosing*/ false, 2243 ConditionVar->getLocation(), 2244 ConditionVar->getType().getNonReferenceType(), 2245 VK_LValue)); 2246 2247 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2248 2249 if (ConvertToBoolean) { 2250 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2251 if (Condition.isInvalid()) 2252 return ExprError(); 2253 } 2254 2255 return Condition; 2256 } 2257 2258 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2259 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2260 // C++ 6.4p4: 2261 // The value of a condition that is an initialized declaration in a statement 2262 // other than a switch statement is the value of the declared variable 2263 // implicitly converted to type bool. If that conversion is ill-formed, the 2264 // program is ill-formed. 2265 // The value of a condition that is an expression is the value of the 2266 // expression, implicitly converted to bool. 2267 // 2268 return PerformContextuallyConvertToBool(CondExpr); 2269 } 2270 2271 /// Helper function to determine whether this is the (deprecated) C++ 2272 /// conversion from a string literal to a pointer to non-const char or 2273 /// non-const wchar_t (for narrow and wide string literals, 2274 /// respectively). 2275 bool 2276 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2277 // Look inside the implicit cast, if it exists. 2278 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2279 From = Cast->getSubExpr(); 2280 2281 // A string literal (2.13.4) that is not a wide string literal can 2282 // be converted to an rvalue of type "pointer to char"; a wide 2283 // string literal can be converted to an rvalue of type "pointer 2284 // to wchar_t" (C++ 4.2p2). 2285 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2286 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2287 if (const BuiltinType *ToPointeeType 2288 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2289 // This conversion is considered only when there is an 2290 // explicit appropriate pointer target type (C++ 4.2p2). 2291 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2292 switch (StrLit->getKind()) { 2293 case StringLiteral::UTF8: 2294 case StringLiteral::UTF16: 2295 case StringLiteral::UTF32: 2296 // We don't allow UTF literals to be implicitly converted 2297 break; 2298 case StringLiteral::Ascii: 2299 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2300 ToPointeeType->getKind() == BuiltinType::Char_S); 2301 case StringLiteral::Wide: 2302 return ToPointeeType->isWideCharType(); 2303 } 2304 } 2305 } 2306 2307 return false; 2308 } 2309 2310 static ExprResult BuildCXXCastArgument(Sema &S, 2311 SourceLocation CastLoc, 2312 QualType Ty, 2313 CastKind Kind, 2314 CXXMethodDecl *Method, 2315 DeclAccessPair FoundDecl, 2316 bool HadMultipleCandidates, 2317 Expr *From) { 2318 switch (Kind) { 2319 default: llvm_unreachable("Unhandled cast kind!"); 2320 case CK_ConstructorConversion: { 2321 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2322 SmallVector<Expr*, 8> ConstructorArgs; 2323 2324 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs)) 2325 return ExprError(); 2326 2327 S.CheckConstructorAccess(CastLoc, Constructor, 2328 InitializedEntity::InitializeTemporary(Ty), 2329 Constructor->getAccess()); 2330 2331 ExprResult Result 2332 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2333 ConstructorArgs, HadMultipleCandidates, 2334 /*ListInit*/ false, /*ZeroInit*/ false, 2335 CXXConstructExpr::CK_Complete, SourceRange()); 2336 if (Result.isInvalid()) 2337 return ExprError(); 2338 2339 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2340 } 2341 2342 case CK_UserDefinedConversion: { 2343 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2344 2345 // Create an implicit call expr that calls it. 2346 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method); 2347 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv, 2348 HadMultipleCandidates); 2349 if (Result.isInvalid()) 2350 return ExprError(); 2351 // Record usage of conversion in an implicit cast. 2352 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2353 Result.get()->getType(), 2354 CK_UserDefinedConversion, 2355 Result.get(), 0, 2356 Result.get()->getValueKind())); 2357 2358 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2359 2360 return S.MaybeBindToTemporary(Result.get()); 2361 } 2362 } 2363 } 2364 2365 /// PerformImplicitConversion - Perform an implicit conversion of the 2366 /// expression From to the type ToType using the pre-computed implicit 2367 /// conversion sequence ICS. Returns the converted 2368 /// expression. Action is the kind of conversion we're performing, 2369 /// used in the error message. 2370 ExprResult 2371 Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2372 const ImplicitConversionSequence &ICS, 2373 AssignmentAction Action, 2374 CheckedConversionKind CCK) { 2375 switch (ICS.getKind()) { 2376 case ImplicitConversionSequence::StandardConversion: { 2377 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2378 Action, CCK); 2379 if (Res.isInvalid()) 2380 return ExprError(); 2381 From = Res.take(); 2382 break; 2383 } 2384 2385 case ImplicitConversionSequence::UserDefinedConversion: { 2386 2387 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2388 CastKind CastKind; 2389 QualType BeforeToType; 2390 assert(FD && "FIXME: aggregate initialization from init list"); 2391 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2392 CastKind = CK_UserDefinedConversion; 2393 2394 // If the user-defined conversion is specified by a conversion function, 2395 // the initial standard conversion sequence converts the source type to 2396 // the implicit object parameter of the conversion function. 2397 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2398 } else { 2399 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2400 CastKind = CK_ConstructorConversion; 2401 // Do no conversion if dealing with ... for the first conversion. 2402 if (!ICS.UserDefined.EllipsisConversion) { 2403 // If the user-defined conversion is specified by a constructor, the 2404 // initial standard conversion sequence converts the source type to the 2405 // type required by the argument of the constructor 2406 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2407 } 2408 } 2409 // Watch out for elipsis conversion. 2410 if (!ICS.UserDefined.EllipsisConversion) { 2411 ExprResult Res = 2412 PerformImplicitConversion(From, BeforeToType, 2413 ICS.UserDefined.Before, AA_Converting, 2414 CCK); 2415 if (Res.isInvalid()) 2416 return ExprError(); 2417 From = Res.take(); 2418 } 2419 2420 ExprResult CastArg 2421 = BuildCXXCastArgument(*this, 2422 From->getLocStart(), 2423 ToType.getNonReferenceType(), 2424 CastKind, cast<CXXMethodDecl>(FD), 2425 ICS.UserDefined.FoundConversionFunction, 2426 ICS.UserDefined.HadMultipleCandidates, 2427 From); 2428 2429 if (CastArg.isInvalid()) 2430 return ExprError(); 2431 2432 From = CastArg.take(); 2433 2434 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2435 AA_Converting, CCK); 2436 } 2437 2438 case ImplicitConversionSequence::AmbiguousConversion: 2439 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2440 PDiag(diag::err_typecheck_ambiguous_condition) 2441 << From->getSourceRange()); 2442 return ExprError(); 2443 2444 case ImplicitConversionSequence::EllipsisConversion: 2445 llvm_unreachable("Cannot perform an ellipsis conversion"); 2446 2447 case ImplicitConversionSequence::BadConversion: 2448 return ExprError(); 2449 } 2450 2451 // Everything went well. 2452 return Owned(From); 2453 } 2454 2455 /// PerformImplicitConversion - Perform an implicit conversion of the 2456 /// expression From to the type ToType by following the standard 2457 /// conversion sequence SCS. Returns the converted 2458 /// expression. Flavor is the context in which we're performing this 2459 /// conversion, for use in error messages. 2460 ExprResult 2461 Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2462 const StandardConversionSequence& SCS, 2463 AssignmentAction Action, 2464 CheckedConversionKind CCK) { 2465 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2466 2467 // Overall FIXME: we are recomputing too many types here and doing far too 2468 // much extra work. What this means is that we need to keep track of more 2469 // information that is computed when we try the implicit conversion initially, 2470 // so that we don't need to recompute anything here. 2471 QualType FromType = From->getType(); 2472 2473 if (SCS.CopyConstructor) { 2474 // FIXME: When can ToType be a reference type? 2475 assert(!ToType->isReferenceType()); 2476 if (SCS.Second == ICK_Derived_To_Base) { 2477 SmallVector<Expr*, 8> ConstructorArgs; 2478 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2479 From, /*FIXME:ConstructLoc*/SourceLocation(), 2480 ConstructorArgs)) 2481 return ExprError(); 2482 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2483 ToType, SCS.CopyConstructor, 2484 ConstructorArgs, 2485 /*HadMultipleCandidates*/ false, 2486 /*ListInit*/ false, /*ZeroInit*/ false, 2487 CXXConstructExpr::CK_Complete, 2488 SourceRange()); 2489 } 2490 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2491 ToType, SCS.CopyConstructor, 2492 From, /*HadMultipleCandidates*/ false, 2493 /*ListInit*/ false, /*ZeroInit*/ false, 2494 CXXConstructExpr::CK_Complete, 2495 SourceRange()); 2496 } 2497 2498 // Resolve overloaded function references. 2499 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2500 DeclAccessPair Found; 2501 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2502 true, Found); 2503 if (!Fn) 2504 return ExprError(); 2505 2506 if (DiagnoseUseOfDecl(Fn, From->getLocStart())) 2507 return ExprError(); 2508 2509 From = FixOverloadedFunctionReference(From, Found, Fn); 2510 FromType = From->getType(); 2511 } 2512 2513 // Perform the first implicit conversion. 2514 switch (SCS.First) { 2515 case ICK_Identity: 2516 // Nothing to do. 2517 break; 2518 2519 case ICK_Lvalue_To_Rvalue: { 2520 assert(From->getObjectKind() != OK_ObjCProperty); 2521 FromType = FromType.getUnqualifiedType(); 2522 ExprResult FromRes = DefaultLvalueConversion(From); 2523 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2524 From = FromRes.take(); 2525 break; 2526 } 2527 2528 case ICK_Array_To_Pointer: 2529 FromType = Context.getArrayDecayedType(FromType); 2530 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2531 VK_RValue, /*BasePath=*/0, CCK).take(); 2532 break; 2533 2534 case ICK_Function_To_Pointer: 2535 FromType = Context.getPointerType(FromType); 2536 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2537 VK_RValue, /*BasePath=*/0, CCK).take(); 2538 break; 2539 2540 default: 2541 llvm_unreachable("Improper first standard conversion"); 2542 } 2543 2544 // Perform the second implicit conversion 2545 switch (SCS.Second) { 2546 case ICK_Identity: 2547 // If both sides are functions (or pointers/references to them), there could 2548 // be incompatible exception declarations. 2549 if (CheckExceptionSpecCompatibility(From, ToType)) 2550 return ExprError(); 2551 // Nothing else to do. 2552 break; 2553 2554 case ICK_NoReturn_Adjustment: 2555 // If both sides are functions (or pointers/references to them), there could 2556 // be incompatible exception declarations. 2557 if (CheckExceptionSpecCompatibility(From, ToType)) 2558 return ExprError(); 2559 2560 From = ImpCastExprToType(From, ToType, CK_NoOp, 2561 VK_RValue, /*BasePath=*/0, CCK).take(); 2562 break; 2563 2564 case ICK_Integral_Promotion: 2565 case ICK_Integral_Conversion: 2566 if (ToType->isBooleanType()) { 2567 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() && 2568 SCS.Second == ICK_Integral_Promotion && 2569 "only enums with fixed underlying type can promote to bool"); 2570 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean, 2571 VK_RValue, /*BasePath=*/0, CCK).take(); 2572 } else { 2573 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2574 VK_RValue, /*BasePath=*/0, CCK).take(); 2575 } 2576 break; 2577 2578 case ICK_Floating_Promotion: 2579 case ICK_Floating_Conversion: 2580 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2581 VK_RValue, /*BasePath=*/0, CCK).take(); 2582 break; 2583 2584 case ICK_Complex_Promotion: 2585 case ICK_Complex_Conversion: { 2586 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2587 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2588 CastKind CK; 2589 if (FromEl->isRealFloatingType()) { 2590 if (ToEl->isRealFloatingType()) 2591 CK = CK_FloatingComplexCast; 2592 else 2593 CK = CK_FloatingComplexToIntegralComplex; 2594 } else if (ToEl->isRealFloatingType()) { 2595 CK = CK_IntegralComplexToFloatingComplex; 2596 } else { 2597 CK = CK_IntegralComplexCast; 2598 } 2599 From = ImpCastExprToType(From, ToType, CK, 2600 VK_RValue, /*BasePath=*/0, CCK).take(); 2601 break; 2602 } 2603 2604 case ICK_Floating_Integral: 2605 if (ToType->isRealFloatingType()) 2606 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2607 VK_RValue, /*BasePath=*/0, CCK).take(); 2608 else 2609 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2610 VK_RValue, /*BasePath=*/0, CCK).take(); 2611 break; 2612 2613 case ICK_Compatible_Conversion: 2614 From = ImpCastExprToType(From, ToType, CK_NoOp, 2615 VK_RValue, /*BasePath=*/0, CCK).take(); 2616 break; 2617 2618 case ICK_Writeback_Conversion: 2619 case ICK_Pointer_Conversion: { 2620 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2621 // Diagnose incompatible Objective-C conversions 2622 if (Action == AA_Initializing || Action == AA_Assigning) 2623 Diag(From->getLocStart(), 2624 diag::ext_typecheck_convert_incompatible_pointer) 2625 << ToType << From->getType() << Action 2626 << From->getSourceRange() << 0; 2627 else 2628 Diag(From->getLocStart(), 2629 diag::ext_typecheck_convert_incompatible_pointer) 2630 << From->getType() << ToType << Action 2631 << From->getSourceRange() << 0; 2632 2633 if (From->getType()->isObjCObjectPointerType() && 2634 ToType->isObjCObjectPointerType()) 2635 EmitRelatedResultTypeNote(From); 2636 } 2637 else if (getLangOpts().ObjCAutoRefCount && 2638 !CheckObjCARCUnavailableWeakConversion(ToType, 2639 From->getType())) { 2640 if (Action == AA_Initializing) 2641 Diag(From->getLocStart(), 2642 diag::err_arc_weak_unavailable_assign); 2643 else 2644 Diag(From->getLocStart(), 2645 diag::err_arc_convesion_of_weak_unavailable) 2646 << (Action == AA_Casting) << From->getType() << ToType 2647 << From->getSourceRange(); 2648 } 2649 2650 CastKind Kind = CK_Invalid; 2651 CXXCastPath BasePath; 2652 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2653 return ExprError(); 2654 2655 // Make sure we extend blocks if necessary. 2656 // FIXME: doing this here is really ugly. 2657 if (Kind == CK_BlockPointerToObjCPointerCast) { 2658 ExprResult E = From; 2659 (void) PrepareCastToObjCObjectPointer(E); 2660 From = E.take(); 2661 } 2662 2663 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2664 .take(); 2665 break; 2666 } 2667 2668 case ICK_Pointer_Member: { 2669 CastKind Kind = CK_Invalid; 2670 CXXCastPath BasePath; 2671 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2672 return ExprError(); 2673 if (CheckExceptionSpecCompatibility(From, ToType)) 2674 return ExprError(); 2675 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2676 .take(); 2677 break; 2678 } 2679 2680 case ICK_Boolean_Conversion: 2681 // Perform half-to-boolean conversion via float. 2682 if (From->getType()->isHalfType()) { 2683 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2684 FromType = Context.FloatTy; 2685 } 2686 2687 From = ImpCastExprToType(From, Context.BoolTy, 2688 ScalarTypeToBooleanCastKind(FromType), 2689 VK_RValue, /*BasePath=*/0, CCK).take(); 2690 break; 2691 2692 case ICK_Derived_To_Base: { 2693 CXXCastPath BasePath; 2694 if (CheckDerivedToBaseConversion(From->getType(), 2695 ToType.getNonReferenceType(), 2696 From->getLocStart(), 2697 From->getSourceRange(), 2698 &BasePath, 2699 CStyle)) 2700 return ExprError(); 2701 2702 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2703 CK_DerivedToBase, From->getValueKind(), 2704 &BasePath, CCK).take(); 2705 break; 2706 } 2707 2708 case ICK_Vector_Conversion: 2709 From = ImpCastExprToType(From, ToType, CK_BitCast, 2710 VK_RValue, /*BasePath=*/0, CCK).take(); 2711 break; 2712 2713 case ICK_Vector_Splat: 2714 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2715 VK_RValue, /*BasePath=*/0, CCK).take(); 2716 break; 2717 2718 case ICK_Complex_Real: 2719 // Case 1. x -> _Complex y 2720 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2721 QualType ElType = ToComplex->getElementType(); 2722 bool isFloatingComplex = ElType->isRealFloatingType(); 2723 2724 // x -> y 2725 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2726 // do nothing 2727 } else if (From->getType()->isRealFloatingType()) { 2728 From = ImpCastExprToType(From, ElType, 2729 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2730 } else { 2731 assert(From->getType()->isIntegerType()); 2732 From = ImpCastExprToType(From, ElType, 2733 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2734 } 2735 // y -> _Complex y 2736 From = ImpCastExprToType(From, ToType, 2737 isFloatingComplex ? CK_FloatingRealToComplex 2738 : CK_IntegralRealToComplex).take(); 2739 2740 // Case 2. _Complex x -> y 2741 } else { 2742 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2743 assert(FromComplex); 2744 2745 QualType ElType = FromComplex->getElementType(); 2746 bool isFloatingComplex = ElType->isRealFloatingType(); 2747 2748 // _Complex x -> x 2749 From = ImpCastExprToType(From, ElType, 2750 isFloatingComplex ? CK_FloatingComplexToReal 2751 : CK_IntegralComplexToReal, 2752 VK_RValue, /*BasePath=*/0, CCK).take(); 2753 2754 // x -> y 2755 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2756 // do nothing 2757 } else if (ToType->isRealFloatingType()) { 2758 From = ImpCastExprToType(From, ToType, 2759 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2760 VK_RValue, /*BasePath=*/0, CCK).take(); 2761 } else { 2762 assert(ToType->isIntegerType()); 2763 From = ImpCastExprToType(From, ToType, 2764 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2765 VK_RValue, /*BasePath=*/0, CCK).take(); 2766 } 2767 } 2768 break; 2769 2770 case ICK_Block_Pointer_Conversion: { 2771 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2772 VK_RValue, /*BasePath=*/0, CCK).take(); 2773 break; 2774 } 2775 2776 case ICK_TransparentUnionConversion: { 2777 ExprResult FromRes = Owned(From); 2778 Sema::AssignConvertType ConvTy = 2779 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2780 if (FromRes.isInvalid()) 2781 return ExprError(); 2782 From = FromRes.take(); 2783 assert ((ConvTy == Sema::Compatible) && 2784 "Improper transparent union conversion"); 2785 (void)ConvTy; 2786 break; 2787 } 2788 2789 case ICK_Zero_Event_Conversion: 2790 From = ImpCastExprToType(From, ToType, 2791 CK_ZeroToOCLEvent, 2792 From->getValueKind()).take(); 2793 break; 2794 2795 case ICK_Lvalue_To_Rvalue: 2796 case ICK_Array_To_Pointer: 2797 case ICK_Function_To_Pointer: 2798 case ICK_Qualification: 2799 case ICK_Num_Conversion_Kinds: 2800 llvm_unreachable("Improper second standard conversion"); 2801 } 2802 2803 switch (SCS.Third) { 2804 case ICK_Identity: 2805 // Nothing to do. 2806 break; 2807 2808 case ICK_Qualification: { 2809 // The qualification keeps the category of the inner expression, unless the 2810 // target type isn't a reference. 2811 ExprValueKind VK = ToType->isReferenceType() ? 2812 From->getValueKind() : VK_RValue; 2813 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2814 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2815 2816 if (SCS.DeprecatedStringLiteralToCharPtr && 2817 !getLangOpts().WritableStrings) 2818 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2819 << ToType.getNonReferenceType(); 2820 2821 break; 2822 } 2823 2824 default: 2825 llvm_unreachable("Improper third standard conversion"); 2826 } 2827 2828 // If this conversion sequence involved a scalar -> atomic conversion, perform 2829 // that conversion now. 2830 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) 2831 if (Context.hasSameType(ToAtomic->getValueType(), From->getType())) 2832 From = ImpCastExprToType(From, ToType, CK_NonAtomicToAtomic, VK_RValue, 0, 2833 CCK).take(); 2834 2835 return Owned(From); 2836 } 2837 2838 ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2839 SourceLocation KWLoc, 2840 ParsedType Ty, 2841 SourceLocation RParen) { 2842 TypeSourceInfo *TSInfo; 2843 QualType T = GetTypeFromParser(Ty, &TSInfo); 2844 2845 if (!TSInfo) 2846 TSInfo = Context.getTrivialTypeSourceInfo(T); 2847 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2848 } 2849 2850 /// \brief Check the completeness of a type in a unary type trait. 2851 /// 2852 /// If the particular type trait requires a complete type, tries to complete 2853 /// it. If completing the type fails, a diagnostic is emitted and false 2854 /// returned. If completing the type succeeds or no completion was required, 2855 /// returns true. 2856 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2857 UnaryTypeTrait UTT, 2858 SourceLocation Loc, 2859 QualType ArgTy) { 2860 // C++0x [meta.unary.prop]p3: 2861 // For all of the class templates X declared in this Clause, instantiating 2862 // that template with a template argument that is a class template 2863 // specialization may result in the implicit instantiation of the template 2864 // argument if and only if the semantics of X require that the argument 2865 // must be a complete type. 2866 // We apply this rule to all the type trait expressions used to implement 2867 // these class templates. We also try to follow any GCC documented behavior 2868 // in these expressions to ensure portability of standard libraries. 2869 switch (UTT) { 2870 // is_complete_type somewhat obviously cannot require a complete type. 2871 case UTT_IsCompleteType: 2872 // Fall-through 2873 2874 // These traits are modeled on the type predicates in C++0x 2875 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2876 // requiring a complete type, as whether or not they return true cannot be 2877 // impacted by the completeness of the type. 2878 case UTT_IsVoid: 2879 case UTT_IsIntegral: 2880 case UTT_IsFloatingPoint: 2881 case UTT_IsArray: 2882 case UTT_IsPointer: 2883 case UTT_IsLvalueReference: 2884 case UTT_IsRvalueReference: 2885 case UTT_IsMemberFunctionPointer: 2886 case UTT_IsMemberObjectPointer: 2887 case UTT_IsEnum: 2888 case UTT_IsUnion: 2889 case UTT_IsClass: 2890 case UTT_IsFunction: 2891 case UTT_IsReference: 2892 case UTT_IsArithmetic: 2893 case UTT_IsFundamental: 2894 case UTT_IsObject: 2895 case UTT_IsScalar: 2896 case UTT_IsCompound: 2897 case UTT_IsMemberPointer: 2898 // Fall-through 2899 2900 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2901 // which requires some of its traits to have the complete type. However, 2902 // the completeness of the type cannot impact these traits' semantics, and 2903 // so they don't require it. This matches the comments on these traits in 2904 // Table 49. 2905 case UTT_IsConst: 2906 case UTT_IsVolatile: 2907 case UTT_IsSigned: 2908 case UTT_IsUnsigned: 2909 return true; 2910 2911 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2912 // applied to a complete type. 2913 case UTT_IsTrivial: 2914 case UTT_IsTriviallyCopyable: 2915 case UTT_IsStandardLayout: 2916 case UTT_IsPOD: 2917 case UTT_IsLiteral: 2918 case UTT_IsEmpty: 2919 case UTT_IsPolymorphic: 2920 case UTT_IsAbstract: 2921 case UTT_IsInterfaceClass: 2922 // Fall-through 2923 2924 // These traits require a complete type. 2925 case UTT_IsFinal: 2926 2927 // These trait expressions are designed to help implement predicates in 2928 // [meta.unary.prop] despite not being named the same. They are specified 2929 // by both GCC and the Embarcadero C++ compiler, and require the complete 2930 // type due to the overarching C++0x type predicates being implemented 2931 // requiring the complete type. 2932 case UTT_HasNothrowAssign: 2933 case UTT_HasNothrowConstructor: 2934 case UTT_HasNothrowCopy: 2935 case UTT_HasTrivialAssign: 2936 case UTT_HasTrivialDefaultConstructor: 2937 case UTT_HasTrivialCopy: 2938 case UTT_HasTrivialDestructor: 2939 case UTT_HasVirtualDestructor: 2940 // Arrays of unknown bound are expressly allowed. 2941 QualType ElTy = ArgTy; 2942 if (ArgTy->isIncompleteArrayType()) 2943 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 2944 2945 // The void type is expressly allowed. 2946 if (ElTy->isVoidType()) 2947 return true; 2948 2949 return !S.RequireCompleteType( 2950 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 2951 } 2952 llvm_unreachable("Type trait not handled by switch"); 2953 } 2954 2955 static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 2956 SourceLocation KeyLoc, QualType T) { 2957 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 2958 2959 ASTContext &C = Self.Context; 2960 switch(UTT) { 2961 // Type trait expressions corresponding to the primary type category 2962 // predicates in C++0x [meta.unary.cat]. 2963 case UTT_IsVoid: 2964 return T->isVoidType(); 2965 case UTT_IsIntegral: 2966 return T->isIntegralType(C); 2967 case UTT_IsFloatingPoint: 2968 return T->isFloatingType(); 2969 case UTT_IsArray: 2970 return T->isArrayType(); 2971 case UTT_IsPointer: 2972 return T->isPointerType(); 2973 case UTT_IsLvalueReference: 2974 return T->isLValueReferenceType(); 2975 case UTT_IsRvalueReference: 2976 return T->isRValueReferenceType(); 2977 case UTT_IsMemberFunctionPointer: 2978 return T->isMemberFunctionPointerType(); 2979 case UTT_IsMemberObjectPointer: 2980 return T->isMemberDataPointerType(); 2981 case UTT_IsEnum: 2982 return T->isEnumeralType(); 2983 case UTT_IsUnion: 2984 return T->isUnionType(); 2985 case UTT_IsClass: 2986 return T->isClassType() || T->isStructureType() || T->isInterfaceType(); 2987 case UTT_IsFunction: 2988 return T->isFunctionType(); 2989 2990 // Type trait expressions which correspond to the convenient composition 2991 // predicates in C++0x [meta.unary.comp]. 2992 case UTT_IsReference: 2993 return T->isReferenceType(); 2994 case UTT_IsArithmetic: 2995 return T->isArithmeticType() && !T->isEnumeralType(); 2996 case UTT_IsFundamental: 2997 return T->isFundamentalType(); 2998 case UTT_IsObject: 2999 return T->isObjectType(); 3000 case UTT_IsScalar: 3001 // Note: semantic analysis depends on Objective-C lifetime types to be 3002 // considered scalar types. However, such types do not actually behave 3003 // like scalar types at run time (since they may require retain/release 3004 // operations), so we report them as non-scalar. 3005 if (T->isObjCLifetimeType()) { 3006 switch (T.getObjCLifetime()) { 3007 case Qualifiers::OCL_None: 3008 case Qualifiers::OCL_ExplicitNone: 3009 return true; 3010 3011 case Qualifiers::OCL_Strong: 3012 case Qualifiers::OCL_Weak: 3013 case Qualifiers::OCL_Autoreleasing: 3014 return false; 3015 } 3016 } 3017 3018 return T->isScalarType(); 3019 case UTT_IsCompound: 3020 return T->isCompoundType(); 3021 case UTT_IsMemberPointer: 3022 return T->isMemberPointerType(); 3023 3024 // Type trait expressions which correspond to the type property predicates 3025 // in C++0x [meta.unary.prop]. 3026 case UTT_IsConst: 3027 return T.isConstQualified(); 3028 case UTT_IsVolatile: 3029 return T.isVolatileQualified(); 3030 case UTT_IsTrivial: 3031 return T.isTrivialType(Self.Context); 3032 case UTT_IsTriviallyCopyable: 3033 return T.isTriviallyCopyableType(Self.Context); 3034 case UTT_IsStandardLayout: 3035 return T->isStandardLayoutType(); 3036 case UTT_IsPOD: 3037 return T.isPODType(Self.Context); 3038 case UTT_IsLiteral: 3039 return T->isLiteralType(); 3040 case UTT_IsEmpty: 3041 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3042 return !RD->isUnion() && RD->isEmpty(); 3043 return false; 3044 case UTT_IsPolymorphic: 3045 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3046 return RD->isPolymorphic(); 3047 return false; 3048 case UTT_IsAbstract: 3049 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3050 return RD->isAbstract(); 3051 return false; 3052 case UTT_IsInterfaceClass: 3053 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3054 return RD->isInterface(); 3055 return false; 3056 case UTT_IsFinal: 3057 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3058 return RD->hasAttr<FinalAttr>(); 3059 return false; 3060 case UTT_IsSigned: 3061 return T->isSignedIntegerType(); 3062 case UTT_IsUnsigned: 3063 return T->isUnsignedIntegerType(); 3064 3065 // Type trait expressions which query classes regarding their construction, 3066 // destruction, and copying. Rather than being based directly on the 3067 // related type predicates in the standard, they are specified by both 3068 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 3069 // specifications. 3070 // 3071 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 3072 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3073 // 3074 // Note that these builtins do not behave as documented in g++: if a class 3075 // has both a trivial and a non-trivial special member of a particular kind, 3076 // they return false! For now, we emulate this behavior. 3077 // FIXME: This appears to be a g++ bug: more complex cases reveal that it 3078 // does not correctly compute triviality in the presence of multiple special 3079 // members of the same kind. Revisit this once the g++ bug is fixed. 3080 case UTT_HasTrivialDefaultConstructor: 3081 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3082 // If __is_pod (type) is true then the trait is true, else if type is 3083 // a cv class or union type (or array thereof) with a trivial default 3084 // constructor ([class.ctor]) then the trait is true, else it is false. 3085 if (T.isPODType(Self.Context)) 3086 return true; 3087 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3088 return RD->hasTrivialDefaultConstructor() && 3089 !RD->hasNonTrivialDefaultConstructor(); 3090 return false; 3091 case UTT_HasTrivialCopy: 3092 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3093 // If __is_pod (type) is true or type is a reference type then 3094 // the trait is true, else if type is a cv class or union type 3095 // with a trivial copy constructor ([class.copy]) then the trait 3096 // is true, else it is false. 3097 if (T.isPODType(Self.Context) || T->isReferenceType()) 3098 return true; 3099 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3100 return RD->hasTrivialCopyConstructor() && 3101 !RD->hasNonTrivialCopyConstructor(); 3102 return false; 3103 case UTT_HasTrivialAssign: 3104 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3105 // If type is const qualified or is a reference type then the 3106 // trait is false. Otherwise if __is_pod (type) is true then the 3107 // trait is true, else if type is a cv class or union type with 3108 // a trivial copy assignment ([class.copy]) then the trait is 3109 // true, else it is false. 3110 // Note: the const and reference restrictions are interesting, 3111 // given that const and reference members don't prevent a class 3112 // from having a trivial copy assignment operator (but do cause 3113 // errors if the copy assignment operator is actually used, q.v. 3114 // [class.copy]p12). 3115 3116 if (T.isConstQualified()) 3117 return false; 3118 if (T.isPODType(Self.Context)) 3119 return true; 3120 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3121 return RD->hasTrivialCopyAssignment() && 3122 !RD->hasNonTrivialCopyAssignment(); 3123 return false; 3124 case UTT_HasTrivialDestructor: 3125 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3126 // If __is_pod (type) is true or type is a reference type 3127 // then the trait is true, else if type is a cv class or union 3128 // type (or array thereof) with a trivial destructor 3129 // ([class.dtor]) then the trait is true, else it is 3130 // false. 3131 if (T.isPODType(Self.Context) || T->isReferenceType()) 3132 return true; 3133 3134 // Objective-C++ ARC: autorelease types don't require destruction. 3135 if (T->isObjCLifetimeType() && 3136 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3137 return true; 3138 3139 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3140 return RD->hasTrivialDestructor(); 3141 return false; 3142 // TODO: Propagate nothrowness for implicitly declared special members. 3143 case UTT_HasNothrowAssign: 3144 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3145 // If type is const qualified or is a reference type then the 3146 // trait is false. Otherwise if __has_trivial_assign (type) 3147 // is true then the trait is true, else if type is a cv class 3148 // or union type with copy assignment operators that are known 3149 // not to throw an exception then the trait is true, else it is 3150 // false. 3151 if (C.getBaseElementType(T).isConstQualified()) 3152 return false; 3153 if (T->isReferenceType()) 3154 return false; 3155 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3156 return true; 3157 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) { 3158 if (RD->hasTrivialCopyAssignment() && !RD->hasNonTrivialCopyAssignment()) 3159 return true; 3160 3161 bool FoundAssign = false; 3162 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(OO_Equal); 3163 LookupResult Res(Self, DeclarationNameInfo(Name, KeyLoc), 3164 Sema::LookupOrdinaryName); 3165 if (Self.LookupQualifiedName(Res, RD)) { 3166 Res.suppressDiagnostics(); 3167 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3168 Op != OpEnd; ++Op) { 3169 if (isa<FunctionTemplateDecl>(*Op)) 3170 continue; 3171 3172 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3173 if (Operator->isCopyAssignmentOperator()) { 3174 FoundAssign = true; 3175 const FunctionProtoType *CPT 3176 = Operator->getType()->getAs<FunctionProtoType>(); 3177 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3178 if (!CPT) 3179 return false; 3180 if (!CPT->isNothrow(Self.Context)) 3181 return false; 3182 } 3183 } 3184 } 3185 3186 return FoundAssign; 3187 } 3188 return false; 3189 case UTT_HasNothrowCopy: 3190 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3191 // If __has_trivial_copy (type) is true then the trait is true, else 3192 // if type is a cv class or union type with copy constructors that are 3193 // known not to throw an exception then the trait is true, else it is 3194 // false. 3195 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3196 return true; 3197 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) { 3198 if (RD->hasTrivialCopyConstructor() && 3199 !RD->hasNonTrivialCopyConstructor()) 3200 return true; 3201 3202 bool FoundConstructor = false; 3203 unsigned FoundTQs; 3204 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3205 for (DeclContext::lookup_const_iterator Con = R.begin(), 3206 ConEnd = R.end(); Con != ConEnd; ++Con) { 3207 // A template constructor is never a copy constructor. 3208 // FIXME: However, it may actually be selected at the actual overload 3209 // resolution point. 3210 if (isa<FunctionTemplateDecl>(*Con)) 3211 continue; 3212 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3213 if (Constructor->isCopyConstructor(FoundTQs)) { 3214 FoundConstructor = true; 3215 const FunctionProtoType *CPT 3216 = Constructor->getType()->getAs<FunctionProtoType>(); 3217 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3218 if (!CPT) 3219 return false; 3220 // FIXME: check whether evaluating default arguments can throw. 3221 // For now, we'll be conservative and assume that they can throw. 3222 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3223 return false; 3224 } 3225 } 3226 3227 return FoundConstructor; 3228 } 3229 return false; 3230 case UTT_HasNothrowConstructor: 3231 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3232 // If __has_trivial_constructor (type) is true then the trait is 3233 // true, else if type is a cv class or union type (or array 3234 // thereof) with a default constructor that is known not to 3235 // throw an exception then the trait is true, else it is false. 3236 if (T.isPODType(C) || T->isObjCLifetimeType()) 3237 return true; 3238 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) { 3239 if (RD->hasTrivialDefaultConstructor() && 3240 !RD->hasNonTrivialDefaultConstructor()) 3241 return true; 3242 3243 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3244 for (DeclContext::lookup_const_iterator Con = R.begin(), 3245 ConEnd = R.end(); Con != ConEnd; ++Con) { 3246 // FIXME: In C++0x, a constructor template can be a default constructor. 3247 if (isa<FunctionTemplateDecl>(*Con)) 3248 continue; 3249 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3250 if (Constructor->isDefaultConstructor()) { 3251 const FunctionProtoType *CPT 3252 = Constructor->getType()->getAs<FunctionProtoType>(); 3253 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3254 if (!CPT) 3255 return false; 3256 // TODO: check whether evaluating default arguments can throw. 3257 // For now, we'll be conservative and assume that they can throw. 3258 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3259 } 3260 } 3261 } 3262 return false; 3263 case UTT_HasVirtualDestructor: 3264 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3265 // If type is a class type with a virtual destructor ([class.dtor]) 3266 // then the trait is true, else it is false. 3267 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3268 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3269 return Destructor->isVirtual(); 3270 return false; 3271 3272 // These type trait expressions are modeled on the specifications for the 3273 // Embarcadero C++0x type trait functions: 3274 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3275 case UTT_IsCompleteType: 3276 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3277 // Returns True if and only if T is a complete type at the point of the 3278 // function call. 3279 return !T->isIncompleteType(); 3280 } 3281 llvm_unreachable("Type trait not covered by switch"); 3282 } 3283 3284 ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3285 SourceLocation KWLoc, 3286 TypeSourceInfo *TSInfo, 3287 SourceLocation RParen) { 3288 QualType T = TSInfo->getType(); 3289 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3290 return ExprError(); 3291 3292 bool Value = false; 3293 if (!T->isDependentType()) 3294 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3295 3296 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3297 RParen, Context.BoolTy)); 3298 } 3299 3300 ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3301 SourceLocation KWLoc, 3302 ParsedType LhsTy, 3303 ParsedType RhsTy, 3304 SourceLocation RParen) { 3305 TypeSourceInfo *LhsTSInfo; 3306 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3307 if (!LhsTSInfo) 3308 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3309 3310 TypeSourceInfo *RhsTSInfo; 3311 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3312 if (!RhsTSInfo) 3313 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3314 3315 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3316 } 3317 3318 /// \brief Determine whether T has a non-trivial Objective-C lifetime in 3319 /// ARC mode. 3320 static bool hasNontrivialObjCLifetime(QualType T) { 3321 switch (T.getObjCLifetime()) { 3322 case Qualifiers::OCL_ExplicitNone: 3323 return false; 3324 3325 case Qualifiers::OCL_Strong: 3326 case Qualifiers::OCL_Weak: 3327 case Qualifiers::OCL_Autoreleasing: 3328 return true; 3329 3330 case Qualifiers::OCL_None: 3331 return T->isObjCLifetimeType(); 3332 } 3333 3334 llvm_unreachable("Unknown ObjC lifetime qualifier"); 3335 } 3336 3337 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc, 3338 ArrayRef<TypeSourceInfo *> Args, 3339 SourceLocation RParenLoc) { 3340 switch (Kind) { 3341 case clang::TT_IsTriviallyConstructible: { 3342 // C++11 [meta.unary.prop]: 3343 // is_trivially_constructible is defined as: 3344 // 3345 // is_constructible<T, Args...>::value is true and the variable 3346 // definition for is_constructible, as defined below, is known to call no 3347 // operation that is not trivial. 3348 // 3349 // The predicate condition for a template specialization 3350 // is_constructible<T, Args...> shall be satisfied if and only if the 3351 // following variable definition would be well-formed for some invented 3352 // variable t: 3353 // 3354 // T t(create<Args>()...); 3355 if (Args.empty()) { 3356 S.Diag(KWLoc, diag::err_type_trait_arity) 3357 << 1 << 1 << 1 << (int)Args.size(); 3358 return false; 3359 } 3360 3361 bool SawVoid = false; 3362 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3363 if (Args[I]->getType()->isVoidType()) { 3364 SawVoid = true; 3365 continue; 3366 } 3367 3368 if (!Args[I]->getType()->isIncompleteType() && 3369 S.RequireCompleteType(KWLoc, Args[I]->getType(), 3370 diag::err_incomplete_type_used_in_type_trait_expr)) 3371 return false; 3372 } 3373 3374 // If any argument was 'void', of course it won't type-check. 3375 if (SawVoid) 3376 return false; 3377 3378 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs; 3379 SmallVector<Expr *, 2> ArgExprs; 3380 ArgExprs.reserve(Args.size() - 1); 3381 for (unsigned I = 1, N = Args.size(); I != N; ++I) { 3382 QualType T = Args[I]->getType(); 3383 if (T->isObjectType() || T->isFunctionType()) 3384 T = S.Context.getRValueReferenceType(T); 3385 OpaqueArgExprs.push_back( 3386 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(), 3387 T.getNonLValueExprType(S.Context), 3388 Expr::getValueKindForType(T))); 3389 ArgExprs.push_back(&OpaqueArgExprs.back()); 3390 } 3391 3392 // Perform the initialization in an unevaluated context within a SFINAE 3393 // trap at translation unit scope. 3394 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated); 3395 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true); 3396 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); 3397 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0])); 3398 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc, 3399 RParenLoc)); 3400 InitializationSequence Init(S, To, InitKind, 3401 ArgExprs.begin(), ArgExprs.size()); 3402 if (Init.Failed()) 3403 return false; 3404 3405 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs); 3406 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3407 return false; 3408 3409 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3410 // lifetime, this is a non-trivial construction. 3411 if (S.getLangOpts().ObjCAutoRefCount && 3412 hasNontrivialObjCLifetime(Args[0]->getType().getNonReferenceType())) 3413 return false; 3414 3415 // The initialization succeeded; now make sure there are no non-trivial 3416 // calls. 3417 return !Result.get()->hasNonTrivialCall(S.Context); 3418 } 3419 } 3420 3421 return false; 3422 } 3423 3424 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3425 ArrayRef<TypeSourceInfo *> Args, 3426 SourceLocation RParenLoc) { 3427 bool Dependent = false; 3428 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3429 if (Args[I]->getType()->isDependentType()) { 3430 Dependent = true; 3431 break; 3432 } 3433 } 3434 3435 bool Value = false; 3436 if (!Dependent) 3437 Value = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc); 3438 3439 return TypeTraitExpr::Create(Context, Context.BoolTy, KWLoc, Kind, 3440 Args, RParenLoc, Value); 3441 } 3442 3443 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3444 ArrayRef<ParsedType> Args, 3445 SourceLocation RParenLoc) { 3446 SmallVector<TypeSourceInfo *, 4> ConvertedArgs; 3447 ConvertedArgs.reserve(Args.size()); 3448 3449 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3450 TypeSourceInfo *TInfo; 3451 QualType T = GetTypeFromParser(Args[I], &TInfo); 3452 if (!TInfo) 3453 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc); 3454 3455 ConvertedArgs.push_back(TInfo); 3456 } 3457 3458 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc); 3459 } 3460 3461 static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3462 QualType LhsT, QualType RhsT, 3463 SourceLocation KeyLoc) { 3464 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3465 "Cannot evaluate traits of dependent types"); 3466 3467 switch(BTT) { 3468 case BTT_IsBaseOf: { 3469 // C++0x [meta.rel]p2 3470 // Base is a base class of Derived without regard to cv-qualifiers or 3471 // Base and Derived are not unions and name the same class type without 3472 // regard to cv-qualifiers. 3473 3474 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3475 if (!lhsRecord) return false; 3476 3477 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3478 if (!rhsRecord) return false; 3479 3480 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3481 == (lhsRecord == rhsRecord)); 3482 3483 if (lhsRecord == rhsRecord) 3484 return !lhsRecord->getDecl()->isUnion(); 3485 3486 // C++0x [meta.rel]p2: 3487 // If Base and Derived are class types and are different types 3488 // (ignoring possible cv-qualifiers) then Derived shall be a 3489 // complete type. 3490 if (Self.RequireCompleteType(KeyLoc, RhsT, 3491 diag::err_incomplete_type_used_in_type_trait_expr)) 3492 return false; 3493 3494 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3495 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3496 } 3497 case BTT_IsSame: 3498 return Self.Context.hasSameType(LhsT, RhsT); 3499 case BTT_TypeCompatible: 3500 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3501 RhsT.getUnqualifiedType()); 3502 case BTT_IsConvertible: 3503 case BTT_IsConvertibleTo: { 3504 // C++0x [meta.rel]p4: 3505 // Given the following function prototype: 3506 // 3507 // template <class T> 3508 // typename add_rvalue_reference<T>::type create(); 3509 // 3510 // the predicate condition for a template specialization 3511 // is_convertible<From, To> shall be satisfied if and only if 3512 // the return expression in the following code would be 3513 // well-formed, including any implicit conversions to the return 3514 // type of the function: 3515 // 3516 // To test() { 3517 // return create<From>(); 3518 // } 3519 // 3520 // Access checking is performed as if in a context unrelated to To and 3521 // From. Only the validity of the immediate context of the expression 3522 // of the return-statement (including conversions to the return type) 3523 // is considered. 3524 // 3525 // We model the initialization as a copy-initialization of a temporary 3526 // of the appropriate type, which for this expression is identical to the 3527 // return statement (since NRVO doesn't apply). 3528 3529 // Functions aren't allowed to return function or array types. 3530 if (RhsT->isFunctionType() || RhsT->isArrayType()) 3531 return false; 3532 3533 // A return statement in a void function must have void type. 3534 if (RhsT->isVoidType()) 3535 return LhsT->isVoidType(); 3536 3537 // A function definition requires a complete, non-abstract return type. 3538 if (Self.RequireCompleteType(KeyLoc, RhsT, 0) || 3539 Self.RequireNonAbstractType(KeyLoc, RhsT, 0)) 3540 return false; 3541 3542 // Compute the result of add_rvalue_reference. 3543 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3544 LhsT = Self.Context.getRValueReferenceType(LhsT); 3545 3546 // Build a fake source and destination for initialization. 3547 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3548 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3549 Expr::getValueKindForType(LhsT)); 3550 Expr *FromPtr = &From; 3551 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3552 SourceLocation())); 3553 3554 // Perform the initialization in an unevaluated context within a SFINAE 3555 // trap at translation unit scope. 3556 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3557 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3558 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3559 InitializationSequence Init(Self, To, Kind, &FromPtr, 1); 3560 if (Init.Failed()) 3561 return false; 3562 3563 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr); 3564 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3565 } 3566 3567 case BTT_IsTriviallyAssignable: { 3568 // C++11 [meta.unary.prop]p3: 3569 // is_trivially_assignable is defined as: 3570 // is_assignable<T, U>::value is true and the assignment, as defined by 3571 // is_assignable, is known to call no operation that is not trivial 3572 // 3573 // is_assignable is defined as: 3574 // The expression declval<T>() = declval<U>() is well-formed when 3575 // treated as an unevaluated operand (Clause 5). 3576 // 3577 // For both, T and U shall be complete types, (possibly cv-qualified) 3578 // void, or arrays of unknown bound. 3579 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() && 3580 Self.RequireCompleteType(KeyLoc, LhsT, 3581 diag::err_incomplete_type_used_in_type_trait_expr)) 3582 return false; 3583 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() && 3584 Self.RequireCompleteType(KeyLoc, RhsT, 3585 diag::err_incomplete_type_used_in_type_trait_expr)) 3586 return false; 3587 3588 // cv void is never assignable. 3589 if (LhsT->isVoidType() || RhsT->isVoidType()) 3590 return false; 3591 3592 // Build expressions that emulate the effect of declval<T>() and 3593 // declval<U>(). 3594 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3595 LhsT = Self.Context.getRValueReferenceType(LhsT); 3596 if (RhsT->isObjectType() || RhsT->isFunctionType()) 3597 RhsT = Self.Context.getRValueReferenceType(RhsT); 3598 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3599 Expr::getValueKindForType(LhsT)); 3600 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context), 3601 Expr::getValueKindForType(RhsT)); 3602 3603 // Attempt the assignment in an unevaluated context within a SFINAE 3604 // trap at translation unit scope. 3605 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3606 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3607 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3608 ExprResult Result = Self.BuildBinOp(/*S=*/0, KeyLoc, BO_Assign, &Lhs, &Rhs); 3609 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3610 return false; 3611 3612 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3613 // lifetime, this is a non-trivial assignment. 3614 if (Self.getLangOpts().ObjCAutoRefCount && 3615 hasNontrivialObjCLifetime(LhsT.getNonReferenceType())) 3616 return false; 3617 3618 return !Result.get()->hasNonTrivialCall(Self.Context); 3619 } 3620 } 3621 llvm_unreachable("Unknown type trait or not implemented"); 3622 } 3623 3624 ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3625 SourceLocation KWLoc, 3626 TypeSourceInfo *LhsTSInfo, 3627 TypeSourceInfo *RhsTSInfo, 3628 SourceLocation RParen) { 3629 QualType LhsT = LhsTSInfo->getType(); 3630 QualType RhsT = RhsTSInfo->getType(); 3631 3632 if (BTT == BTT_TypeCompatible) { 3633 if (getLangOpts().CPlusPlus) { 3634 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3635 << SourceRange(KWLoc, RParen); 3636 return ExprError(); 3637 } 3638 } 3639 3640 bool Value = false; 3641 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3642 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3643 3644 // Select trait result type. 3645 QualType ResultType; 3646 switch (BTT) { 3647 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3648 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3649 case BTT_IsSame: ResultType = Context.BoolTy; break; 3650 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3651 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3652 case BTT_IsTriviallyAssignable: ResultType = Context.BoolTy; 3653 } 3654 3655 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3656 RhsTSInfo, Value, RParen, 3657 ResultType)); 3658 } 3659 3660 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3661 SourceLocation KWLoc, 3662 ParsedType Ty, 3663 Expr* DimExpr, 3664 SourceLocation RParen) { 3665 TypeSourceInfo *TSInfo; 3666 QualType T = GetTypeFromParser(Ty, &TSInfo); 3667 if (!TSInfo) 3668 TSInfo = Context.getTrivialTypeSourceInfo(T); 3669 3670 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3671 } 3672 3673 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3674 QualType T, Expr *DimExpr, 3675 SourceLocation KeyLoc) { 3676 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3677 3678 switch(ATT) { 3679 case ATT_ArrayRank: 3680 if (T->isArrayType()) { 3681 unsigned Dim = 0; 3682 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3683 ++Dim; 3684 T = AT->getElementType(); 3685 } 3686 return Dim; 3687 } 3688 return 0; 3689 3690 case ATT_ArrayExtent: { 3691 llvm::APSInt Value; 3692 uint64_t Dim; 3693 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3694 diag::err_dimension_expr_not_constant_integer, 3695 false).isInvalid()) 3696 return 0; 3697 if (Value.isSigned() && Value.isNegative()) { 3698 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer) 3699 << DimExpr->getSourceRange(); 3700 return 0; 3701 } 3702 Dim = Value.getLimitedValue(); 3703 3704 if (T->isArrayType()) { 3705 unsigned D = 0; 3706 bool Matched = false; 3707 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3708 if (Dim == D) { 3709 Matched = true; 3710 break; 3711 } 3712 ++D; 3713 T = AT->getElementType(); 3714 } 3715 3716 if (Matched && T->isArrayType()) { 3717 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3718 return CAT->getSize().getLimitedValue(); 3719 } 3720 } 3721 return 0; 3722 } 3723 } 3724 llvm_unreachable("Unknown type trait or not implemented"); 3725 } 3726 3727 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3728 SourceLocation KWLoc, 3729 TypeSourceInfo *TSInfo, 3730 Expr* DimExpr, 3731 SourceLocation RParen) { 3732 QualType T = TSInfo->getType(); 3733 3734 // FIXME: This should likely be tracked as an APInt to remove any host 3735 // assumptions about the width of size_t on the target. 3736 uint64_t Value = 0; 3737 if (!T->isDependentType()) 3738 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3739 3740 // While the specification for these traits from the Embarcadero C++ 3741 // compiler's documentation says the return type is 'unsigned int', Clang 3742 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3743 // compiler, there is no difference. On several other platforms this is an 3744 // important distinction. 3745 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3746 DimExpr, RParen, 3747 Context.getSizeType())); 3748 } 3749 3750 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3751 SourceLocation KWLoc, 3752 Expr *Queried, 3753 SourceLocation RParen) { 3754 // If error parsing the expression, ignore. 3755 if (!Queried) 3756 return ExprError(); 3757 3758 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3759 3760 return Result; 3761 } 3762 3763 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3764 switch (ET) { 3765 case ET_IsLValueExpr: return E->isLValue(); 3766 case ET_IsRValueExpr: return E->isRValue(); 3767 } 3768 llvm_unreachable("Expression trait not covered by switch"); 3769 } 3770 3771 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3772 SourceLocation KWLoc, 3773 Expr *Queried, 3774 SourceLocation RParen) { 3775 if (Queried->isTypeDependent()) { 3776 // Delay type-checking for type-dependent expressions. 3777 } else if (Queried->getType()->isPlaceholderType()) { 3778 ExprResult PE = CheckPlaceholderExpr(Queried); 3779 if (PE.isInvalid()) return ExprError(); 3780 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3781 } 3782 3783 bool Value = EvaluateExpressionTrait(ET, Queried); 3784 3785 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3786 RParen, Context.BoolTy)); 3787 } 3788 3789 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3790 ExprValueKind &VK, 3791 SourceLocation Loc, 3792 bool isIndirect) { 3793 assert(!LHS.get()->getType()->isPlaceholderType() && 3794 !RHS.get()->getType()->isPlaceholderType() && 3795 "placeholders should have been weeded out by now"); 3796 3797 // The LHS undergoes lvalue conversions if this is ->*. 3798 if (isIndirect) { 3799 LHS = DefaultLvalueConversion(LHS.take()); 3800 if (LHS.isInvalid()) return QualType(); 3801 } 3802 3803 // The RHS always undergoes lvalue conversions. 3804 RHS = DefaultLvalueConversion(RHS.take()); 3805 if (RHS.isInvalid()) return QualType(); 3806 3807 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3808 // C++ 5.5p2 3809 // The binary operator .* [p3: ->*] binds its second operand, which shall 3810 // be of type "pointer to member of T" (where T is a completely-defined 3811 // class type) [...] 3812 QualType RHSType = RHS.get()->getType(); 3813 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3814 if (!MemPtr) { 3815 Diag(Loc, diag::err_bad_memptr_rhs) 3816 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3817 return QualType(); 3818 } 3819 3820 QualType Class(MemPtr->getClass(), 0); 3821 3822 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3823 // member pointer points must be completely-defined. However, there is no 3824 // reason for this semantic distinction, and the rule is not enforced by 3825 // other compilers. Therefore, we do not check this property, as it is 3826 // likely to be considered a defect. 3827 3828 // C++ 5.5p2 3829 // [...] to its first operand, which shall be of class T or of a class of 3830 // which T is an unambiguous and accessible base class. [p3: a pointer to 3831 // such a class] 3832 QualType LHSType = LHS.get()->getType(); 3833 if (isIndirect) { 3834 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3835 LHSType = Ptr->getPointeeType(); 3836 else { 3837 Diag(Loc, diag::err_bad_memptr_lhs) 3838 << OpSpelling << 1 << LHSType 3839 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3840 return QualType(); 3841 } 3842 } 3843 3844 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3845 // If we want to check the hierarchy, we need a complete type. 3846 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs, 3847 OpSpelling, (int)isIndirect)) { 3848 return QualType(); 3849 } 3850 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3851 /*DetectVirtual=*/false); 3852 // FIXME: Would it be useful to print full ambiguity paths, or is that 3853 // overkill? 3854 if (!IsDerivedFrom(LHSType, Class, Paths) || 3855 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3856 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3857 << (int)isIndirect << LHS.get()->getType(); 3858 return QualType(); 3859 } 3860 // Cast LHS to type of use. 3861 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3862 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3863 3864 CXXCastPath BasePath; 3865 BuildBasePathArray(Paths, BasePath); 3866 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3867 &BasePath); 3868 } 3869 3870 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3871 // Diagnose use of pointer-to-member type which when used as 3872 // the functional cast in a pointer-to-member expression. 3873 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3874 return QualType(); 3875 } 3876 3877 // C++ 5.5p2 3878 // The result is an object or a function of the type specified by the 3879 // second operand. 3880 // The cv qualifiers are the union of those in the pointer and the left side, 3881 // in accordance with 5.5p5 and 5.2.5. 3882 QualType Result = MemPtr->getPointeeType(); 3883 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3884 3885 // C++0x [expr.mptr.oper]p6: 3886 // In a .* expression whose object expression is an rvalue, the program is 3887 // ill-formed if the second operand is a pointer to member function with 3888 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3889 // expression is an lvalue, the program is ill-formed if the second operand 3890 // is a pointer to member function with ref-qualifier &&. 3891 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3892 switch (Proto->getRefQualifier()) { 3893 case RQ_None: 3894 // Do nothing 3895 break; 3896 3897 case RQ_LValue: 3898 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3899 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3900 << RHSType << 1 << LHS.get()->getSourceRange(); 3901 break; 3902 3903 case RQ_RValue: 3904 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 3905 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3906 << RHSType << 0 << LHS.get()->getSourceRange(); 3907 break; 3908 } 3909 } 3910 3911 // C++ [expr.mptr.oper]p6: 3912 // The result of a .* expression whose second operand is a pointer 3913 // to a data member is of the same value category as its 3914 // first operand. The result of a .* expression whose second 3915 // operand is a pointer to a member function is a prvalue. The 3916 // result of an ->* expression is an lvalue if its second operand 3917 // is a pointer to data member and a prvalue otherwise. 3918 if (Result->isFunctionType()) { 3919 VK = VK_RValue; 3920 return Context.BoundMemberTy; 3921 } else if (isIndirect) { 3922 VK = VK_LValue; 3923 } else { 3924 VK = LHS.get()->getValueKind(); 3925 } 3926 3927 return Result; 3928 } 3929 3930 /// \brief Try to convert a type to another according to C++0x 5.16p3. 3931 /// 3932 /// This is part of the parameter validation for the ? operator. If either 3933 /// value operand is a class type, the two operands are attempted to be 3934 /// converted to each other. This function does the conversion in one direction. 3935 /// It returns true if the program is ill-formed and has already been diagnosed 3936 /// as such. 3937 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 3938 SourceLocation QuestionLoc, 3939 bool &HaveConversion, 3940 QualType &ToType) { 3941 HaveConversion = false; 3942 ToType = To->getType(); 3943 3944 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 3945 SourceLocation()); 3946 // C++0x 5.16p3 3947 // The process for determining whether an operand expression E1 of type T1 3948 // can be converted to match an operand expression E2 of type T2 is defined 3949 // as follows: 3950 // -- If E2 is an lvalue: 3951 bool ToIsLvalue = To->isLValue(); 3952 if (ToIsLvalue) { 3953 // E1 can be converted to match E2 if E1 can be implicitly converted to 3954 // type "lvalue reference to T2", subject to the constraint that in the 3955 // conversion the reference must bind directly to E1. 3956 QualType T = Self.Context.getLValueReferenceType(ToType); 3957 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3958 3959 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3960 if (InitSeq.isDirectReferenceBinding()) { 3961 ToType = T; 3962 HaveConversion = true; 3963 return false; 3964 } 3965 3966 if (InitSeq.isAmbiguous()) 3967 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3968 } 3969 3970 // -- If E2 is an rvalue, or if the conversion above cannot be done: 3971 // -- if E1 and E2 have class type, and the underlying class types are 3972 // the same or one is a base class of the other: 3973 QualType FTy = From->getType(); 3974 QualType TTy = To->getType(); 3975 const RecordType *FRec = FTy->getAs<RecordType>(); 3976 const RecordType *TRec = TTy->getAs<RecordType>(); 3977 bool FDerivedFromT = FRec && TRec && FRec != TRec && 3978 Self.IsDerivedFrom(FTy, TTy); 3979 if (FRec && TRec && 3980 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 3981 // E1 can be converted to match E2 if the class of T2 is the 3982 // same type as, or a base class of, the class of T1, and 3983 // [cv2 > cv1]. 3984 if (FRec == TRec || FDerivedFromT) { 3985 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 3986 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3987 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3988 if (InitSeq) { 3989 HaveConversion = true; 3990 return false; 3991 } 3992 3993 if (InitSeq.isAmbiguous()) 3994 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3995 } 3996 } 3997 3998 return false; 3999 } 4000 4001 // -- Otherwise: E1 can be converted to match E2 if E1 can be 4002 // implicitly converted to the type that expression E2 would have 4003 // if E2 were converted to an rvalue (or the type it has, if E2 is 4004 // an rvalue). 4005 // 4006 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 4007 // to the array-to-pointer or function-to-pointer conversions. 4008 if (!TTy->getAs<TagType>()) 4009 TTy = TTy.getUnqualifiedType(); 4010 4011 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 4012 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 4013 HaveConversion = !InitSeq.Failed(); 4014 ToType = TTy; 4015 if (InitSeq.isAmbiguous()) 4016 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 4017 4018 return false; 4019 } 4020 4021 /// \brief Try to find a common type for two according to C++0x 5.16p5. 4022 /// 4023 /// This is part of the parameter validation for the ? operator. If either 4024 /// value operand is a class type, overload resolution is used to find a 4025 /// conversion to a common type. 4026 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 4027 SourceLocation QuestionLoc) { 4028 Expr *Args[2] = { LHS.get(), RHS.get() }; 4029 OverloadCandidateSet CandidateSet(QuestionLoc); 4030 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 2, 4031 CandidateSet); 4032 4033 OverloadCandidateSet::iterator Best; 4034 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 4035 case OR_Success: { 4036 // We found a match. Perform the conversions on the arguments and move on. 4037 ExprResult LHSRes = 4038 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 4039 Best->Conversions[0], Sema::AA_Converting); 4040 if (LHSRes.isInvalid()) 4041 break; 4042 LHS = LHSRes; 4043 4044 ExprResult RHSRes = 4045 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 4046 Best->Conversions[1], Sema::AA_Converting); 4047 if (RHSRes.isInvalid()) 4048 break; 4049 RHS = RHSRes; 4050 if (Best->Function) 4051 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 4052 return false; 4053 } 4054 4055 case OR_No_Viable_Function: 4056 4057 // Emit a better diagnostic if one of the expressions is a null pointer 4058 // constant and the other is a pointer type. In this case, the user most 4059 // likely forgot to take the address of the other expression. 4060 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4061 return true; 4062 4063 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4064 << LHS.get()->getType() << RHS.get()->getType() 4065 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4066 return true; 4067 4068 case OR_Ambiguous: 4069 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 4070 << LHS.get()->getType() << RHS.get()->getType() 4071 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4072 // FIXME: Print the possible common types by printing the return types of 4073 // the viable candidates. 4074 break; 4075 4076 case OR_Deleted: 4077 llvm_unreachable("Conditional operator has only built-in overloads"); 4078 } 4079 return true; 4080 } 4081 4082 /// \brief Perform an "extended" implicit conversion as returned by 4083 /// TryClassUnification. 4084 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 4085 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 4086 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 4087 SourceLocation()); 4088 Expr *Arg = E.take(); 4089 InitializationSequence InitSeq(Self, Entity, Kind, &Arg, 1); 4090 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg); 4091 if (Result.isInvalid()) 4092 return true; 4093 4094 E = Result; 4095 return false; 4096 } 4097 4098 /// \brief Check the operands of ?: under C++ semantics. 4099 /// 4100 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 4101 /// extension. In this case, LHS == Cond. (But they're not aliases.) 4102 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 4103 ExprResult &RHS, ExprValueKind &VK, 4104 ExprObjectKind &OK, 4105 SourceLocation QuestionLoc) { 4106 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 4107 // interface pointers. 4108 4109 // C++11 [expr.cond]p1 4110 // The first expression is contextually converted to bool. 4111 if (!Cond.get()->isTypeDependent()) { 4112 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 4113 if (CondRes.isInvalid()) 4114 return QualType(); 4115 Cond = CondRes; 4116 } 4117 4118 // Assume r-value. 4119 VK = VK_RValue; 4120 OK = OK_Ordinary; 4121 4122 // Either of the arguments dependent? 4123 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 4124 return Context.DependentTy; 4125 4126 // C++11 [expr.cond]p2 4127 // If either the second or the third operand has type (cv) void, ... 4128 QualType LTy = LHS.get()->getType(); 4129 QualType RTy = RHS.get()->getType(); 4130 bool LVoid = LTy->isVoidType(); 4131 bool RVoid = RTy->isVoidType(); 4132 if (LVoid || RVoid) { 4133 // ... then the [l2r] conversions are performed on the second and third 4134 // operands ... 4135 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4136 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4137 if (LHS.isInvalid() || RHS.isInvalid()) 4138 return QualType(); 4139 4140 // Finish off the lvalue-to-rvalue conversion by copy-initializing a 4141 // temporary if necessary. DefaultFunctionArrayLvalueConversion doesn't 4142 // do this part for us. 4143 ExprResult &NonVoid = LVoid ? RHS : LHS; 4144 if (NonVoid.get()->getType()->isRecordType() && 4145 NonVoid.get()->isGLValue()) { 4146 if (RequireNonAbstractType(QuestionLoc, NonVoid.get()->getType(), 4147 diag::err_allocation_of_abstract_type)) 4148 return QualType(); 4149 InitializedEntity Entity = 4150 InitializedEntity::InitializeTemporary(NonVoid.get()->getType()); 4151 NonVoid = PerformCopyInitialization(Entity, SourceLocation(), NonVoid); 4152 if (NonVoid.isInvalid()) 4153 return QualType(); 4154 } 4155 4156 LTy = LHS.get()->getType(); 4157 RTy = RHS.get()->getType(); 4158 4159 // ... and one of the following shall hold: 4160 // -- The second or the third operand (but not both) is a throw- 4161 // expression; the result is of the type of the other and is a prvalue. 4162 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 4163 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 4164 if (LThrow && !RThrow) 4165 return RTy; 4166 if (RThrow && !LThrow) 4167 return LTy; 4168 4169 // -- Both the second and third operands have type void; the result is of 4170 // type void and is a prvalue. 4171 if (LVoid && RVoid) 4172 return Context.VoidTy; 4173 4174 // Neither holds, error. 4175 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 4176 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 4177 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4178 return QualType(); 4179 } 4180 4181 // Neither is void. 4182 4183 // C++11 [expr.cond]p3 4184 // Otherwise, if the second and third operand have different types, and 4185 // either has (cv) class type [...] an attempt is made to convert each of 4186 // those operands to the type of the other. 4187 if (!Context.hasSameType(LTy, RTy) && 4188 (LTy->isRecordType() || RTy->isRecordType())) { 4189 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 4190 // These return true if a single direction is already ambiguous. 4191 QualType L2RType, R2LType; 4192 bool HaveL2R, HaveR2L; 4193 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 4194 return QualType(); 4195 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 4196 return QualType(); 4197 4198 // If both can be converted, [...] the program is ill-formed. 4199 if (HaveL2R && HaveR2L) { 4200 Diag(QuestionLoc, diag::err_conditional_ambiguous) 4201 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4202 return QualType(); 4203 } 4204 4205 // If exactly one conversion is possible, that conversion is applied to 4206 // the chosen operand and the converted operands are used in place of the 4207 // original operands for the remainder of this section. 4208 if (HaveL2R) { 4209 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 4210 return QualType(); 4211 LTy = LHS.get()->getType(); 4212 } else if (HaveR2L) { 4213 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 4214 return QualType(); 4215 RTy = RHS.get()->getType(); 4216 } 4217 } 4218 4219 // C++11 [expr.cond]p3 4220 // if both are glvalues of the same value category and the same type except 4221 // for cv-qualification, an attempt is made to convert each of those 4222 // operands to the type of the other. 4223 ExprValueKind LVK = LHS.get()->getValueKind(); 4224 ExprValueKind RVK = RHS.get()->getValueKind(); 4225 if (!Context.hasSameType(LTy, RTy) && 4226 Context.hasSameUnqualifiedType(LTy, RTy) && 4227 LVK == RVK && LVK != VK_RValue) { 4228 // Since the unqualified types are reference-related and we require the 4229 // result to be as if a reference bound directly, the only conversion 4230 // we can perform is to add cv-qualifiers. 4231 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers()); 4232 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers()); 4233 if (RCVR.isStrictSupersetOf(LCVR)) { 4234 LHS = ImpCastExprToType(LHS.take(), RTy, CK_NoOp, LVK); 4235 LTy = LHS.get()->getType(); 4236 } 4237 else if (LCVR.isStrictSupersetOf(RCVR)) { 4238 RHS = ImpCastExprToType(RHS.take(), LTy, CK_NoOp, RVK); 4239 RTy = RHS.get()->getType(); 4240 } 4241 } 4242 4243 // C++11 [expr.cond]p4 4244 // If the second and third operands are glvalues of the same value 4245 // category and have the same type, the result is of that type and 4246 // value category and it is a bit-field if the second or the third 4247 // operand is a bit-field, or if both are bit-fields. 4248 // We only extend this to bitfields, not to the crazy other kinds of 4249 // l-values. 4250 bool Same = Context.hasSameType(LTy, RTy); 4251 if (Same && LVK == RVK && LVK != VK_RValue && 4252 LHS.get()->isOrdinaryOrBitFieldObject() && 4253 RHS.get()->isOrdinaryOrBitFieldObject()) { 4254 VK = LHS.get()->getValueKind(); 4255 if (LHS.get()->getObjectKind() == OK_BitField || 4256 RHS.get()->getObjectKind() == OK_BitField) 4257 OK = OK_BitField; 4258 return LTy; 4259 } 4260 4261 // C++11 [expr.cond]p5 4262 // Otherwise, the result is a prvalue. If the second and third operands 4263 // do not have the same type, and either has (cv) class type, ... 4264 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 4265 // ... overload resolution is used to determine the conversions (if any) 4266 // to be applied to the operands. If the overload resolution fails, the 4267 // program is ill-formed. 4268 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 4269 return QualType(); 4270 } 4271 4272 // C++11 [expr.cond]p6 4273 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard 4274 // conversions are performed on the second and third operands. 4275 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4276 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4277 if (LHS.isInvalid() || RHS.isInvalid()) 4278 return QualType(); 4279 LTy = LHS.get()->getType(); 4280 RTy = RHS.get()->getType(); 4281 4282 // After those conversions, one of the following shall hold: 4283 // -- The second and third operands have the same type; the result 4284 // is of that type. If the operands have class type, the result 4285 // is a prvalue temporary of the result type, which is 4286 // copy-initialized from either the second operand or the third 4287 // operand depending on the value of the first operand. 4288 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 4289 if (LTy->isRecordType()) { 4290 // The operands have class type. Make a temporary copy. 4291 if (RequireNonAbstractType(QuestionLoc, LTy, 4292 diag::err_allocation_of_abstract_type)) 4293 return QualType(); 4294 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 4295 4296 ExprResult LHSCopy = PerformCopyInitialization(Entity, 4297 SourceLocation(), 4298 LHS); 4299 if (LHSCopy.isInvalid()) 4300 return QualType(); 4301 4302 ExprResult RHSCopy = PerformCopyInitialization(Entity, 4303 SourceLocation(), 4304 RHS); 4305 if (RHSCopy.isInvalid()) 4306 return QualType(); 4307 4308 LHS = LHSCopy; 4309 RHS = RHSCopy; 4310 } 4311 4312 return LTy; 4313 } 4314 4315 // Extension: conditional operator involving vector types. 4316 if (LTy->isVectorType() || RTy->isVectorType()) 4317 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4318 4319 // -- The second and third operands have arithmetic or enumeration type; 4320 // the usual arithmetic conversions are performed to bring them to a 4321 // common type, and the result is of that type. 4322 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 4323 UsualArithmeticConversions(LHS, RHS); 4324 if (LHS.isInvalid() || RHS.isInvalid()) 4325 return QualType(); 4326 return LHS.get()->getType(); 4327 } 4328 4329 // -- The second and third operands have pointer type, or one has pointer 4330 // type and the other is a null pointer constant, or both are null 4331 // pointer constants, at least one of which is non-integral; pointer 4332 // conversions and qualification conversions are performed to bring them 4333 // to their composite pointer type. The result is of the composite 4334 // pointer type. 4335 // -- The second and third operands have pointer to member type, or one has 4336 // pointer to member type and the other is a null pointer constant; 4337 // pointer to member conversions and qualification conversions are 4338 // performed to bring them to a common type, whose cv-qualification 4339 // shall match the cv-qualification of either the second or the third 4340 // operand. The result is of the common type. 4341 bool NonStandardCompositeType = false; 4342 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 4343 isSFINAEContext()? 0 : &NonStandardCompositeType); 4344 if (!Composite.isNull()) { 4345 if (NonStandardCompositeType) 4346 Diag(QuestionLoc, 4347 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 4348 << LTy << RTy << Composite 4349 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4350 4351 return Composite; 4352 } 4353 4354 // Similarly, attempt to find composite type of two objective-c pointers. 4355 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 4356 if (!Composite.isNull()) 4357 return Composite; 4358 4359 // Check if we are using a null with a non-pointer type. 4360 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4361 return QualType(); 4362 4363 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4364 << LHS.get()->getType() << RHS.get()->getType() 4365 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4366 return QualType(); 4367 } 4368 4369 /// \brief Find a merged pointer type and convert the two expressions to it. 4370 /// 4371 /// This finds the composite pointer type (or member pointer type) for @p E1 4372 /// and @p E2 according to C++11 5.9p2. It converts both expressions to this 4373 /// type and returns it. 4374 /// It does not emit diagnostics. 4375 /// 4376 /// \param Loc The location of the operator requiring these two expressions to 4377 /// be converted to the composite pointer type. 4378 /// 4379 /// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4380 /// a non-standard (but still sane) composite type to which both expressions 4381 /// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4382 /// will be set true. 4383 QualType Sema::FindCompositePointerType(SourceLocation Loc, 4384 Expr *&E1, Expr *&E2, 4385 bool *NonStandardCompositeType) { 4386 if (NonStandardCompositeType) 4387 *NonStandardCompositeType = false; 4388 4389 assert(getLangOpts().CPlusPlus && "This function assumes C++"); 4390 QualType T1 = E1->getType(), T2 = E2->getType(); 4391 4392 // C++11 5.9p2 4393 // Pointer conversions and qualification conversions are performed on 4394 // pointer operands to bring them to their composite pointer type. If 4395 // one operand is a null pointer constant, the composite pointer type is 4396 // std::nullptr_t if the other operand is also a null pointer constant or, 4397 // if the other operand is a pointer, the type of the other operand. 4398 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4399 !T2->isAnyPointerType() && !T2->isMemberPointerType()) { 4400 if (T1->isNullPtrType() && 4401 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4402 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4403 return T1; 4404 } 4405 if (T2->isNullPtrType() && 4406 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4407 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4408 return T2; 4409 } 4410 return QualType(); 4411 } 4412 4413 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4414 if (T2->isMemberPointerType()) 4415 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4416 else 4417 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4418 return T2; 4419 } 4420 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4421 if (T1->isMemberPointerType()) 4422 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4423 else 4424 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4425 return T1; 4426 } 4427 4428 // Now both have to be pointers or member pointers. 4429 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4430 (!T2->isPointerType() && !T2->isMemberPointerType())) 4431 return QualType(); 4432 4433 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4434 // the other has type "pointer to cv2 T" and the composite pointer type is 4435 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4436 // Otherwise, the composite pointer type is a pointer type similar to the 4437 // type of one of the operands, with a cv-qualification signature that is 4438 // the union of the cv-qualification signatures of the operand types. 4439 // In practice, the first part here is redundant; it's subsumed by the second. 4440 // What we do here is, we build the two possible composite types, and try the 4441 // conversions in both directions. If only one works, or if the two composite 4442 // types are the same, we have succeeded. 4443 // FIXME: extended qualifiers? 4444 typedef SmallVector<unsigned, 4> QualifierVector; 4445 QualifierVector QualifierUnion; 4446 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4447 ContainingClassVector; 4448 ContainingClassVector MemberOfClass; 4449 QualType Composite1 = Context.getCanonicalType(T1), 4450 Composite2 = Context.getCanonicalType(T2); 4451 unsigned NeedConstBefore = 0; 4452 do { 4453 const PointerType *Ptr1, *Ptr2; 4454 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4455 (Ptr2 = Composite2->getAs<PointerType>())) { 4456 Composite1 = Ptr1->getPointeeType(); 4457 Composite2 = Ptr2->getPointeeType(); 4458 4459 // If we're allowed to create a non-standard composite type, keep track 4460 // of where we need to fill in additional 'const' qualifiers. 4461 if (NonStandardCompositeType && 4462 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4463 NeedConstBefore = QualifierUnion.size(); 4464 4465 QualifierUnion.push_back( 4466 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4467 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4468 continue; 4469 } 4470 4471 const MemberPointerType *MemPtr1, *MemPtr2; 4472 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4473 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4474 Composite1 = MemPtr1->getPointeeType(); 4475 Composite2 = MemPtr2->getPointeeType(); 4476 4477 // If we're allowed to create a non-standard composite type, keep track 4478 // of where we need to fill in additional 'const' qualifiers. 4479 if (NonStandardCompositeType && 4480 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4481 NeedConstBefore = QualifierUnion.size(); 4482 4483 QualifierUnion.push_back( 4484 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4485 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4486 MemPtr2->getClass())); 4487 continue; 4488 } 4489 4490 // FIXME: block pointer types? 4491 4492 // Cannot unwrap any more types. 4493 break; 4494 } while (true); 4495 4496 if (NeedConstBefore && NonStandardCompositeType) { 4497 // Extension: Add 'const' to qualifiers that come before the first qualifier 4498 // mismatch, so that our (non-standard!) composite type meets the 4499 // requirements of C++ [conv.qual]p4 bullet 3. 4500 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4501 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4502 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4503 *NonStandardCompositeType = true; 4504 } 4505 } 4506 } 4507 4508 // Rewrap the composites as pointers or member pointers with the union CVRs. 4509 ContainingClassVector::reverse_iterator MOC 4510 = MemberOfClass.rbegin(); 4511 for (QualifierVector::reverse_iterator 4512 I = QualifierUnion.rbegin(), 4513 E = QualifierUnion.rend(); 4514 I != E; (void)++I, ++MOC) { 4515 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4516 if (MOC->first && MOC->second) { 4517 // Rebuild member pointer type 4518 Composite1 = Context.getMemberPointerType( 4519 Context.getQualifiedType(Composite1, Quals), 4520 MOC->first); 4521 Composite2 = Context.getMemberPointerType( 4522 Context.getQualifiedType(Composite2, Quals), 4523 MOC->second); 4524 } else { 4525 // Rebuild pointer type 4526 Composite1 4527 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4528 Composite2 4529 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4530 } 4531 } 4532 4533 // Try to convert to the first composite pointer type. 4534 InitializedEntity Entity1 4535 = InitializedEntity::InitializeTemporary(Composite1); 4536 InitializationKind Kind 4537 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4538 InitializationSequence E1ToC1(*this, Entity1, Kind, &E1, 1); 4539 InitializationSequence E2ToC1(*this, Entity1, Kind, &E2, 1); 4540 4541 if (E1ToC1 && E2ToC1) { 4542 // Conversion to Composite1 is viable. 4543 if (!Context.hasSameType(Composite1, Composite2)) { 4544 // Composite2 is a different type from Composite1. Check whether 4545 // Composite2 is also viable. 4546 InitializedEntity Entity2 4547 = InitializedEntity::InitializeTemporary(Composite2); 4548 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4549 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4550 if (E1ToC2 && E2ToC2) { 4551 // Both Composite1 and Composite2 are viable and are different; 4552 // this is an ambiguity. 4553 return QualType(); 4554 } 4555 } 4556 4557 // Convert E1 to Composite1 4558 ExprResult E1Result 4559 = E1ToC1.Perform(*this, Entity1, Kind, E1); 4560 if (E1Result.isInvalid()) 4561 return QualType(); 4562 E1 = E1Result.takeAs<Expr>(); 4563 4564 // Convert E2 to Composite1 4565 ExprResult E2Result 4566 = E2ToC1.Perform(*this, Entity1, Kind, E2); 4567 if (E2Result.isInvalid()) 4568 return QualType(); 4569 E2 = E2Result.takeAs<Expr>(); 4570 4571 return Composite1; 4572 } 4573 4574 // Check whether Composite2 is viable. 4575 InitializedEntity Entity2 4576 = InitializedEntity::InitializeTemporary(Composite2); 4577 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4578 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4579 if (!E1ToC2 || !E2ToC2) 4580 return QualType(); 4581 4582 // Convert E1 to Composite2 4583 ExprResult E1Result 4584 = E1ToC2.Perform(*this, Entity2, Kind, E1); 4585 if (E1Result.isInvalid()) 4586 return QualType(); 4587 E1 = E1Result.takeAs<Expr>(); 4588 4589 // Convert E2 to Composite2 4590 ExprResult E2Result 4591 = E2ToC2.Perform(*this, Entity2, Kind, E2); 4592 if (E2Result.isInvalid()) 4593 return QualType(); 4594 E2 = E2Result.takeAs<Expr>(); 4595 4596 return Composite2; 4597 } 4598 4599 ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4600 if (!E) 4601 return ExprError(); 4602 4603 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4604 4605 // If the result is a glvalue, we shouldn't bind it. 4606 if (!E->isRValue()) 4607 return Owned(E); 4608 4609 // In ARC, calls that return a retainable type can return retained, 4610 // in which case we have to insert a consuming cast. 4611 if (getLangOpts().ObjCAutoRefCount && 4612 E->getType()->isObjCRetainableType()) { 4613 4614 bool ReturnsRetained; 4615 4616 // For actual calls, we compute this by examining the type of the 4617 // called value. 4618 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4619 Expr *Callee = Call->getCallee()->IgnoreParens(); 4620 QualType T = Callee->getType(); 4621 4622 if (T == Context.BoundMemberTy) { 4623 // Handle pointer-to-members. 4624 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4625 T = BinOp->getRHS()->getType(); 4626 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4627 T = Mem->getMemberDecl()->getType(); 4628 } 4629 4630 if (const PointerType *Ptr = T->getAs<PointerType>()) 4631 T = Ptr->getPointeeType(); 4632 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4633 T = Ptr->getPointeeType(); 4634 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4635 T = MemPtr->getPointeeType(); 4636 4637 const FunctionType *FTy = T->getAs<FunctionType>(); 4638 assert(FTy && "call to value not of function type?"); 4639 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4640 4641 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4642 // type always produce a +1 object. 4643 } else if (isa<StmtExpr>(E)) { 4644 ReturnsRetained = true; 4645 4646 // We hit this case with the lambda conversion-to-block optimization; 4647 // we don't want any extra casts here. 4648 } else if (isa<CastExpr>(E) && 4649 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) { 4650 return Owned(E); 4651 4652 // For message sends and property references, we try to find an 4653 // actual method. FIXME: we should infer retention by selector in 4654 // cases where we don't have an actual method. 4655 } else { 4656 ObjCMethodDecl *D = 0; 4657 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4658 D = Send->getMethodDecl(); 4659 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) { 4660 D = BoxedExpr->getBoxingMethod(); 4661 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) { 4662 D = ArrayLit->getArrayWithObjectsMethod(); 4663 } else if (ObjCDictionaryLiteral *DictLit 4664 = dyn_cast<ObjCDictionaryLiteral>(E)) { 4665 D = DictLit->getDictWithObjectsMethod(); 4666 } 4667 4668 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4669 4670 // Don't do reclaims on performSelector calls; despite their 4671 // return type, the invoked method doesn't necessarily actually 4672 // return an object. 4673 if (!ReturnsRetained && 4674 D && D->getMethodFamily() == OMF_performSelector) 4675 return Owned(E); 4676 } 4677 4678 // Don't reclaim an object of Class type. 4679 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4680 return Owned(E); 4681 4682 ExprNeedsCleanups = true; 4683 4684 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4685 : CK_ARCReclaimReturnedObject); 4686 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4687 VK_RValue)); 4688 } 4689 4690 if (!getLangOpts().CPlusPlus) 4691 return Owned(E); 4692 4693 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4694 // a fast path for the common case that the type is directly a RecordType. 4695 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4696 const RecordType *RT = 0; 4697 while (!RT) { 4698 switch (T->getTypeClass()) { 4699 case Type::Record: 4700 RT = cast<RecordType>(T); 4701 break; 4702 case Type::ConstantArray: 4703 case Type::IncompleteArray: 4704 case Type::VariableArray: 4705 case Type::DependentSizedArray: 4706 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4707 break; 4708 default: 4709 return Owned(E); 4710 } 4711 } 4712 4713 // That should be enough to guarantee that this type is complete, if we're 4714 // not processing a decltype expression. 4715 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4716 if (RD->isInvalidDecl() || RD->isDependentContext()) 4717 return Owned(E); 4718 4719 bool IsDecltype = ExprEvalContexts.back().IsDecltype; 4720 CXXDestructorDecl *Destructor = IsDecltype ? 0 : LookupDestructor(RD); 4721 4722 if (Destructor) { 4723 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4724 CheckDestructorAccess(E->getExprLoc(), Destructor, 4725 PDiag(diag::err_access_dtor_temp) 4726 << E->getType()); 4727 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 4728 4729 // If destructor is trivial, we can avoid the extra copy. 4730 if (Destructor->isTrivial()) 4731 return Owned(E); 4732 4733 // We need a cleanup, but we don't need to remember the temporary. 4734 ExprNeedsCleanups = true; 4735 } 4736 4737 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4738 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E); 4739 4740 if (IsDecltype) 4741 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind); 4742 4743 return Owned(Bind); 4744 } 4745 4746 ExprResult 4747 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4748 if (SubExpr.isInvalid()) 4749 return ExprError(); 4750 4751 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4752 } 4753 4754 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4755 assert(SubExpr && "sub expression can't be null!"); 4756 4757 CleanupVarDeclMarking(); 4758 4759 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4760 assert(ExprCleanupObjects.size() >= FirstCleanup); 4761 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4762 if (!ExprNeedsCleanups) 4763 return SubExpr; 4764 4765 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4766 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4767 ExprCleanupObjects.size() - FirstCleanup); 4768 4769 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4770 DiscardCleanupsInEvaluationContext(); 4771 4772 return E; 4773 } 4774 4775 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4776 assert(SubStmt && "sub statement can't be null!"); 4777 4778 CleanupVarDeclMarking(); 4779 4780 if (!ExprNeedsCleanups) 4781 return SubStmt; 4782 4783 // FIXME: In order to attach the temporaries, wrap the statement into 4784 // a StmtExpr; currently this is only used for asm statements. 4785 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4786 // a new AsmStmtWithTemporaries. 4787 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt, 4788 SourceLocation(), 4789 SourceLocation()); 4790 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4791 SourceLocation()); 4792 return MaybeCreateExprWithCleanups(E); 4793 } 4794 4795 /// Process the expression contained within a decltype. For such expressions, 4796 /// certain semantic checks on temporaries are delayed until this point, and 4797 /// are omitted for the 'topmost' call in the decltype expression. If the 4798 /// topmost call bound a temporary, strip that temporary off the expression. 4799 ExprResult Sema::ActOnDecltypeExpression(Expr *E) { 4800 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression"); 4801 4802 // C++11 [expr.call]p11: 4803 // If a function call is a prvalue of object type, 4804 // -- if the function call is either 4805 // -- the operand of a decltype-specifier, or 4806 // -- the right operand of a comma operator that is the operand of a 4807 // decltype-specifier, 4808 // a temporary object is not introduced for the prvalue. 4809 4810 // Recursively rebuild ParenExprs and comma expressions to strip out the 4811 // outermost CXXBindTemporaryExpr, if any. 4812 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 4813 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr()); 4814 if (SubExpr.isInvalid()) 4815 return ExprError(); 4816 if (SubExpr.get() == PE->getSubExpr()) 4817 return Owned(E); 4818 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.take()); 4819 } 4820 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 4821 if (BO->getOpcode() == BO_Comma) { 4822 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS()); 4823 if (RHS.isInvalid()) 4824 return ExprError(); 4825 if (RHS.get() == BO->getRHS()) 4826 return Owned(E); 4827 return Owned(new (Context) BinaryOperator(BO->getLHS(), RHS.take(), 4828 BO_Comma, BO->getType(), 4829 BO->getValueKind(), 4830 BO->getObjectKind(), 4831 BO->getOperatorLoc(), 4832 BO->isFPContractable())); 4833 } 4834 } 4835 4836 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E); 4837 if (TopBind) 4838 E = TopBind->getSubExpr(); 4839 4840 // Disable the special decltype handling now. 4841 ExprEvalContexts.back().IsDecltype = false; 4842 4843 // In MS mode, don't perform any extra checking of call return types within a 4844 // decltype expression. 4845 if (getLangOpts().MicrosoftMode) 4846 return Owned(E); 4847 4848 // Perform the semantic checks we delayed until this point. 4849 CallExpr *TopCall = dyn_cast<CallExpr>(E); 4850 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size(); 4851 I != N; ++I) { 4852 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I]; 4853 if (Call == TopCall) 4854 continue; 4855 4856 if (CheckCallReturnType(Call->getCallReturnType(), 4857 Call->getLocStart(), 4858 Call, Call->getDirectCallee())) 4859 return ExprError(); 4860 } 4861 4862 // Now all relevant types are complete, check the destructors are accessible 4863 // and non-deleted, and annotate them on the temporaries. 4864 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size(); 4865 I != N; ++I) { 4866 CXXBindTemporaryExpr *Bind = 4867 ExprEvalContexts.back().DelayedDecltypeBinds[I]; 4868 if (Bind == TopBind) 4869 continue; 4870 4871 CXXTemporary *Temp = Bind->getTemporary(); 4872 4873 CXXRecordDecl *RD = 4874 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 4875 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4876 Temp->setDestructor(Destructor); 4877 4878 MarkFunctionReferenced(Bind->getExprLoc(), Destructor); 4879 CheckDestructorAccess(Bind->getExprLoc(), Destructor, 4880 PDiag(diag::err_access_dtor_temp) 4881 << Bind->getType()); 4882 DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()); 4883 4884 // We need a cleanup, but we don't need to remember the temporary. 4885 ExprNeedsCleanups = true; 4886 } 4887 4888 // Possibly strip off the top CXXBindTemporaryExpr. 4889 return Owned(E); 4890 } 4891 4892 ExprResult 4893 Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4894 tok::TokenKind OpKind, ParsedType &ObjectType, 4895 bool &MayBePseudoDestructor) { 4896 // Since this might be a postfix expression, get rid of ParenListExprs. 4897 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4898 if (Result.isInvalid()) return ExprError(); 4899 Base = Result.get(); 4900 4901 Result = CheckPlaceholderExpr(Base); 4902 if (Result.isInvalid()) return ExprError(); 4903 Base = Result.take(); 4904 4905 QualType BaseType = Base->getType(); 4906 MayBePseudoDestructor = false; 4907 if (BaseType->isDependentType()) { 4908 // If we have a pointer to a dependent type and are using the -> operator, 4909 // the object type is the type that the pointer points to. We might still 4910 // have enough information about that type to do something useful. 4911 if (OpKind == tok::arrow) 4912 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 4913 BaseType = Ptr->getPointeeType(); 4914 4915 ObjectType = ParsedType::make(BaseType); 4916 MayBePseudoDestructor = true; 4917 return Owned(Base); 4918 } 4919 4920 // C++ [over.match.oper]p8: 4921 // [...] When operator->returns, the operator-> is applied to the value 4922 // returned, with the original second operand. 4923 if (OpKind == tok::arrow) { 4924 // The set of types we've considered so far. 4925 llvm::SmallPtrSet<CanQualType,8> CTypes; 4926 SmallVector<SourceLocation, 8> Locations; 4927 CTypes.insert(Context.getCanonicalType(BaseType)); 4928 4929 while (BaseType->isRecordType()) { 4930 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 4931 if (Result.isInvalid()) 4932 return ExprError(); 4933 Base = Result.get(); 4934 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 4935 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 4936 BaseType = Base->getType(); 4937 CanQualType CBaseType = Context.getCanonicalType(BaseType); 4938 if (!CTypes.insert(CBaseType)) { 4939 Diag(OpLoc, diag::err_operator_arrow_circular); 4940 for (unsigned i = 0; i < Locations.size(); i++) 4941 Diag(Locations[i], diag::note_declared_at); 4942 return ExprError(); 4943 } 4944 } 4945 4946 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 4947 BaseType = BaseType->getPointeeType(); 4948 } 4949 4950 // Objective-C properties allow "." access on Objective-C pointer types, 4951 // so adjust the base type to the object type itself. 4952 if (BaseType->isObjCObjectPointerType()) 4953 BaseType = BaseType->getPointeeType(); 4954 4955 // C++ [basic.lookup.classref]p2: 4956 // [...] If the type of the object expression is of pointer to scalar 4957 // type, the unqualified-id is looked up in the context of the complete 4958 // postfix-expression. 4959 // 4960 // This also indicates that we could be parsing a pseudo-destructor-name. 4961 // Note that Objective-C class and object types can be pseudo-destructor 4962 // expressions or normal member (ivar or property) access expressions. 4963 if (BaseType->isObjCObjectOrInterfaceType()) { 4964 MayBePseudoDestructor = true; 4965 } else if (!BaseType->isRecordType()) { 4966 ObjectType = ParsedType(); 4967 MayBePseudoDestructor = true; 4968 return Owned(Base); 4969 } 4970 4971 // The object type must be complete (or dependent), or 4972 // C++11 [expr.prim.general]p3: 4973 // Unlike the object expression in other contexts, *this is not required to 4974 // be of complete type for purposes of class member access (5.2.5) outside 4975 // the member function body. 4976 if (!BaseType->isDependentType() && 4977 !isThisOutsideMemberFunctionBody(BaseType) && 4978 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access)) 4979 return ExprError(); 4980 4981 // C++ [basic.lookup.classref]p2: 4982 // If the id-expression in a class member access (5.2.5) is an 4983 // unqualified-id, and the type of the object expression is of a class 4984 // type C (or of pointer to a class type C), the unqualified-id is looked 4985 // up in the scope of class C. [...] 4986 ObjectType = ParsedType::make(BaseType); 4987 return Base; 4988 } 4989 4990 ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 4991 Expr *MemExpr) { 4992 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 4993 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 4994 << isa<CXXPseudoDestructorExpr>(MemExpr) 4995 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 4996 4997 return ActOnCallExpr(/*Scope*/ 0, 4998 MemExpr, 4999 /*LPLoc*/ ExpectedLParenLoc, 5000 MultiExprArg(), 5001 /*RPLoc*/ ExpectedLParenLoc); 5002 } 5003 5004 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 5005 tok::TokenKind& OpKind, SourceLocation OpLoc) { 5006 if (Base->hasPlaceholderType()) { 5007 ExprResult result = S.CheckPlaceholderExpr(Base); 5008 if (result.isInvalid()) return true; 5009 Base = result.take(); 5010 } 5011 ObjectType = Base->getType(); 5012 5013 // C++ [expr.pseudo]p2: 5014 // The left-hand side of the dot operator shall be of scalar type. The 5015 // left-hand side of the arrow operator shall be of pointer to scalar type. 5016 // This scalar type is the object type. 5017 // Note that this is rather different from the normal handling for the 5018 // arrow operator. 5019 if (OpKind == tok::arrow) { 5020 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 5021 ObjectType = Ptr->getPointeeType(); 5022 } else if (!Base->isTypeDependent()) { 5023 // The user wrote "p->" when she probably meant "p."; fix it. 5024 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 5025 << ObjectType << true 5026 << FixItHint::CreateReplacement(OpLoc, "."); 5027 if (S.isSFINAEContext()) 5028 return true; 5029 5030 OpKind = tok::period; 5031 } 5032 } 5033 5034 return false; 5035 } 5036 5037 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 5038 SourceLocation OpLoc, 5039 tok::TokenKind OpKind, 5040 const CXXScopeSpec &SS, 5041 TypeSourceInfo *ScopeTypeInfo, 5042 SourceLocation CCLoc, 5043 SourceLocation TildeLoc, 5044 PseudoDestructorTypeStorage Destructed, 5045 bool HasTrailingLParen) { 5046 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 5047 5048 QualType ObjectType; 5049 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5050 return ExprError(); 5051 5052 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() && 5053 !ObjectType->isVectorType()) { 5054 if (getLangOpts().MicrosoftMode && ObjectType->isVoidType()) 5055 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 5056 else 5057 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 5058 << ObjectType << Base->getSourceRange(); 5059 return ExprError(); 5060 } 5061 5062 // C++ [expr.pseudo]p2: 5063 // [...] The cv-unqualified versions of the object type and of the type 5064 // designated by the pseudo-destructor-name shall be the same type. 5065 if (DestructedTypeInfo) { 5066 QualType DestructedType = DestructedTypeInfo->getType(); 5067 SourceLocation DestructedTypeStart 5068 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 5069 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 5070 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 5071 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 5072 << ObjectType << DestructedType << Base->getSourceRange() 5073 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5074 5075 // Recover by setting the destructed type to the object type. 5076 DestructedType = ObjectType; 5077 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5078 DestructedTypeStart); 5079 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5080 } else if (DestructedType.getObjCLifetime() != 5081 ObjectType.getObjCLifetime()) { 5082 5083 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 5084 // Okay: just pretend that the user provided the correctly-qualified 5085 // type. 5086 } else { 5087 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 5088 << ObjectType << DestructedType << Base->getSourceRange() 5089 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5090 } 5091 5092 // Recover by setting the destructed type to the object type. 5093 DestructedType = ObjectType; 5094 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5095 DestructedTypeStart); 5096 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5097 } 5098 } 5099 } 5100 5101 // C++ [expr.pseudo]p2: 5102 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 5103 // form 5104 // 5105 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 5106 // 5107 // shall designate the same scalar type. 5108 if (ScopeTypeInfo) { 5109 QualType ScopeType = ScopeTypeInfo->getType(); 5110 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 5111 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 5112 5113 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 5114 diag::err_pseudo_dtor_type_mismatch) 5115 << ObjectType << ScopeType << Base->getSourceRange() 5116 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 5117 5118 ScopeType = QualType(); 5119 ScopeTypeInfo = 0; 5120 } 5121 } 5122 5123 Expr *Result 5124 = new (Context) CXXPseudoDestructorExpr(Context, Base, 5125 OpKind == tok::arrow, OpLoc, 5126 SS.getWithLocInContext(Context), 5127 ScopeTypeInfo, 5128 CCLoc, 5129 TildeLoc, 5130 Destructed); 5131 5132 if (HasTrailingLParen) 5133 return Owned(Result); 5134 5135 return DiagnoseDtorReference(Destructed.getLocation(), Result); 5136 } 5137 5138 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5139 SourceLocation OpLoc, 5140 tok::TokenKind OpKind, 5141 CXXScopeSpec &SS, 5142 UnqualifiedId &FirstTypeName, 5143 SourceLocation CCLoc, 5144 SourceLocation TildeLoc, 5145 UnqualifiedId &SecondTypeName, 5146 bool HasTrailingLParen) { 5147 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5148 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5149 "Invalid first type name in pseudo-destructor"); 5150 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5151 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5152 "Invalid second type name in pseudo-destructor"); 5153 5154 QualType ObjectType; 5155 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5156 return ExprError(); 5157 5158 // Compute the object type that we should use for name lookup purposes. Only 5159 // record types and dependent types matter. 5160 ParsedType ObjectTypePtrForLookup; 5161 if (!SS.isSet()) { 5162 if (ObjectType->isRecordType()) 5163 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 5164 else if (ObjectType->isDependentType()) 5165 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 5166 } 5167 5168 // Convert the name of the type being destructed (following the ~) into a 5169 // type (with source-location information). 5170 QualType DestructedType; 5171 TypeSourceInfo *DestructedTypeInfo = 0; 5172 PseudoDestructorTypeStorage Destructed; 5173 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5174 ParsedType T = getTypeName(*SecondTypeName.Identifier, 5175 SecondTypeName.StartLocation, 5176 S, &SS, true, false, ObjectTypePtrForLookup); 5177 if (!T && 5178 ((SS.isSet() && !computeDeclContext(SS, false)) || 5179 (!SS.isSet() && ObjectType->isDependentType()))) { 5180 // The name of the type being destroyed is a dependent name, and we 5181 // couldn't find anything useful in scope. Just store the identifier and 5182 // it's location, and we'll perform (qualified) name lookup again at 5183 // template instantiation time. 5184 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 5185 SecondTypeName.StartLocation); 5186 } else if (!T) { 5187 Diag(SecondTypeName.StartLocation, 5188 diag::err_pseudo_dtor_destructor_non_type) 5189 << SecondTypeName.Identifier << ObjectType; 5190 if (isSFINAEContext()) 5191 return ExprError(); 5192 5193 // Recover by assuming we had the right type all along. 5194 DestructedType = ObjectType; 5195 } else 5196 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 5197 } else { 5198 // Resolve the template-id to a type. 5199 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 5200 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5201 TemplateId->NumArgs); 5202 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5203 TemplateId->TemplateKWLoc, 5204 TemplateId->Template, 5205 TemplateId->TemplateNameLoc, 5206 TemplateId->LAngleLoc, 5207 TemplateArgsPtr, 5208 TemplateId->RAngleLoc); 5209 if (T.isInvalid() || !T.get()) { 5210 // Recover by assuming we had the right type all along. 5211 DestructedType = ObjectType; 5212 } else 5213 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 5214 } 5215 5216 // If we've performed some kind of recovery, (re-)build the type source 5217 // information. 5218 if (!DestructedType.isNull()) { 5219 if (!DestructedTypeInfo) 5220 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 5221 SecondTypeName.StartLocation); 5222 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5223 } 5224 5225 // Convert the name of the scope type (the type prior to '::') into a type. 5226 TypeSourceInfo *ScopeTypeInfo = 0; 5227 QualType ScopeType; 5228 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5229 FirstTypeName.Identifier) { 5230 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5231 ParsedType T = getTypeName(*FirstTypeName.Identifier, 5232 FirstTypeName.StartLocation, 5233 S, &SS, true, false, ObjectTypePtrForLookup); 5234 if (!T) { 5235 Diag(FirstTypeName.StartLocation, 5236 diag::err_pseudo_dtor_destructor_non_type) 5237 << FirstTypeName.Identifier << ObjectType; 5238 5239 if (isSFINAEContext()) 5240 return ExprError(); 5241 5242 // Just drop this type. It's unnecessary anyway. 5243 ScopeType = QualType(); 5244 } else 5245 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 5246 } else { 5247 // Resolve the template-id to a type. 5248 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 5249 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5250 TemplateId->NumArgs); 5251 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5252 TemplateId->TemplateKWLoc, 5253 TemplateId->Template, 5254 TemplateId->TemplateNameLoc, 5255 TemplateId->LAngleLoc, 5256 TemplateArgsPtr, 5257 TemplateId->RAngleLoc); 5258 if (T.isInvalid() || !T.get()) { 5259 // Recover by dropping this type. 5260 ScopeType = QualType(); 5261 } else 5262 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 5263 } 5264 } 5265 5266 if (!ScopeType.isNull() && !ScopeTypeInfo) 5267 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 5268 FirstTypeName.StartLocation); 5269 5270 5271 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 5272 ScopeTypeInfo, CCLoc, TildeLoc, 5273 Destructed, HasTrailingLParen); 5274 } 5275 5276 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5277 SourceLocation OpLoc, 5278 tok::TokenKind OpKind, 5279 SourceLocation TildeLoc, 5280 const DeclSpec& DS, 5281 bool HasTrailingLParen) { 5282 QualType ObjectType; 5283 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5284 return ExprError(); 5285 5286 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 5287 5288 TypeLocBuilder TLB; 5289 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 5290 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 5291 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 5292 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 5293 5294 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 5295 0, SourceLocation(), TildeLoc, 5296 Destructed, HasTrailingLParen); 5297 } 5298 5299 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 5300 CXXConversionDecl *Method, 5301 bool HadMultipleCandidates) { 5302 if (Method->getParent()->isLambda() && 5303 Method->getConversionType()->isBlockPointerType()) { 5304 // This is a lambda coversion to block pointer; check if the argument 5305 // is a LambdaExpr. 5306 Expr *SubE = E; 5307 CastExpr *CE = dyn_cast<CastExpr>(SubE); 5308 if (CE && CE->getCastKind() == CK_NoOp) 5309 SubE = CE->getSubExpr(); 5310 SubE = SubE->IgnoreParens(); 5311 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE)) 5312 SubE = BE->getSubExpr(); 5313 if (isa<LambdaExpr>(SubE)) { 5314 // For the conversion to block pointer on a lambda expression, we 5315 // construct a special BlockLiteral instead; this doesn't really make 5316 // a difference in ARC, but outside of ARC the resulting block literal 5317 // follows the normal lifetime rules for block literals instead of being 5318 // autoreleased. 5319 DiagnosticErrorTrap Trap(Diags); 5320 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(), 5321 E->getExprLoc(), 5322 Method, E); 5323 if (Exp.isInvalid()) 5324 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv); 5325 return Exp; 5326 } 5327 } 5328 5329 5330 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 5331 FoundDecl, Method); 5332 if (Exp.isInvalid()) 5333 return true; 5334 5335 MemberExpr *ME = 5336 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 5337 SourceLocation(), Context.BoundMemberTy, 5338 VK_RValue, OK_Ordinary); 5339 if (HadMultipleCandidates) 5340 ME->setHadMultipleCandidates(true); 5341 MarkMemberReferenced(ME); 5342 5343 QualType ResultType = Method->getResultType(); 5344 ExprValueKind VK = Expr::getValueKindForType(ResultType); 5345 ResultType = ResultType.getNonLValueExprType(Context); 5346 5347 CXXMemberCallExpr *CE = 5348 new (Context) CXXMemberCallExpr(Context, ME, MultiExprArg(), ResultType, VK, 5349 Exp.get()->getLocEnd()); 5350 return CE; 5351 } 5352 5353 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 5354 SourceLocation RParen) { 5355 CanThrowResult CanThrow = canThrow(Operand); 5356 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 5357 CanThrow, KeyLoc, RParen)); 5358 } 5359 5360 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 5361 Expr *Operand, SourceLocation RParen) { 5362 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 5363 } 5364 5365 static bool IsSpecialDiscardedValue(Expr *E) { 5366 // In C++11, discarded-value expressions of a certain form are special, 5367 // according to [expr]p10: 5368 // The lvalue-to-rvalue conversion (4.1) is applied only if the 5369 // expression is an lvalue of volatile-qualified type and it has 5370 // one of the following forms: 5371 E = E->IgnoreParens(); 5372 5373 // - id-expression (5.1.1), 5374 if (isa<DeclRefExpr>(E)) 5375 return true; 5376 5377 // - subscripting (5.2.1), 5378 if (isa<ArraySubscriptExpr>(E)) 5379 return true; 5380 5381 // - class member access (5.2.5), 5382 if (isa<MemberExpr>(E)) 5383 return true; 5384 5385 // - indirection (5.3.1), 5386 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) 5387 if (UO->getOpcode() == UO_Deref) 5388 return true; 5389 5390 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 5391 // - pointer-to-member operation (5.5), 5392 if (BO->isPtrMemOp()) 5393 return true; 5394 5395 // - comma expression (5.18) where the right operand is one of the above. 5396 if (BO->getOpcode() == BO_Comma) 5397 return IsSpecialDiscardedValue(BO->getRHS()); 5398 } 5399 5400 // - conditional expression (5.16) where both the second and the third 5401 // operands are one of the above, or 5402 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) 5403 return IsSpecialDiscardedValue(CO->getTrueExpr()) && 5404 IsSpecialDiscardedValue(CO->getFalseExpr()); 5405 // The related edge case of "*x ?: *x". 5406 if (BinaryConditionalOperator *BCO = 5407 dyn_cast<BinaryConditionalOperator>(E)) { 5408 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr())) 5409 return IsSpecialDiscardedValue(OVE->getSourceExpr()) && 5410 IsSpecialDiscardedValue(BCO->getFalseExpr()); 5411 } 5412 5413 // Objective-C++ extensions to the rule. 5414 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E)) 5415 return true; 5416 5417 return false; 5418 } 5419 5420 /// Perform the conversions required for an expression used in a 5421 /// context that ignores the result. 5422 ExprResult Sema::IgnoredValueConversions(Expr *E) { 5423 if (E->hasPlaceholderType()) { 5424 ExprResult result = CheckPlaceholderExpr(E); 5425 if (result.isInvalid()) return Owned(E); 5426 E = result.take(); 5427 } 5428 5429 // C99 6.3.2.1: 5430 // [Except in specific positions,] an lvalue that does not have 5431 // array type is converted to the value stored in the 5432 // designated object (and is no longer an lvalue). 5433 if (E->isRValue()) { 5434 // In C, function designators (i.e. expressions of function type) 5435 // are r-values, but we still want to do function-to-pointer decay 5436 // on them. This is both technically correct and convenient for 5437 // some clients. 5438 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType()) 5439 return DefaultFunctionArrayConversion(E); 5440 5441 return Owned(E); 5442 } 5443 5444 if (getLangOpts().CPlusPlus) { 5445 // The C++11 standard defines the notion of a discarded-value expression; 5446 // normally, we don't need to do anything to handle it, but if it is a 5447 // volatile lvalue with a special form, we perform an lvalue-to-rvalue 5448 // conversion. 5449 if (getLangOpts().CPlusPlus11 && E->isGLValue() && 5450 E->getType().isVolatileQualified() && 5451 IsSpecialDiscardedValue(E)) { 5452 ExprResult Res = DefaultLvalueConversion(E); 5453 if (Res.isInvalid()) 5454 return Owned(E); 5455 E = Res.take(); 5456 } 5457 return Owned(E); 5458 } 5459 5460 // GCC seems to also exclude expressions of incomplete enum type. 5461 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 5462 if (!T->getDecl()->isComplete()) { 5463 // FIXME: stupid workaround for a codegen bug! 5464 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 5465 return Owned(E); 5466 } 5467 } 5468 5469 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 5470 if (Res.isInvalid()) 5471 return Owned(E); 5472 E = Res.take(); 5473 5474 if (!E->getType()->isVoidType()) 5475 RequireCompleteType(E->getExprLoc(), E->getType(), 5476 diag::err_incomplete_type); 5477 return Owned(E); 5478 } 5479 5480 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC, 5481 bool DiscardedValue, 5482 bool IsConstexpr) { 5483 ExprResult FullExpr = Owned(FE); 5484 5485 if (!FullExpr.get()) 5486 return ExprError(); 5487 5488 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 5489 return ExprError(); 5490 5491 // Top-level expressions default to 'id' when we're in a debugger. 5492 if (DiscardedValue && getLangOpts().DebuggerCastResultToId && 5493 FullExpr.get()->getType() == Context.UnknownAnyTy) { 5494 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 5495 if (FullExpr.isInvalid()) 5496 return ExprError(); 5497 } 5498 5499 if (DiscardedValue) { 5500 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 5501 if (FullExpr.isInvalid()) 5502 return ExprError(); 5503 5504 FullExpr = IgnoredValueConversions(FullExpr.take()); 5505 if (FullExpr.isInvalid()) 5506 return ExprError(); 5507 } 5508 5509 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr); 5510 return MaybeCreateExprWithCleanups(FullExpr); 5511 } 5512 5513 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 5514 if (!FullStmt) return StmtError(); 5515 5516 return MaybeCreateStmtWithCleanups(FullStmt); 5517 } 5518 5519 Sema::IfExistsResult 5520 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 5521 CXXScopeSpec &SS, 5522 const DeclarationNameInfo &TargetNameInfo) { 5523 DeclarationName TargetName = TargetNameInfo.getName(); 5524 if (!TargetName) 5525 return IER_DoesNotExist; 5526 5527 // If the name itself is dependent, then the result is dependent. 5528 if (TargetName.isDependentName()) 5529 return IER_Dependent; 5530 5531 // Do the redeclaration lookup in the current scope. 5532 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 5533 Sema::NotForRedeclaration); 5534 LookupParsedName(R, S, &SS); 5535 R.suppressDiagnostics(); 5536 5537 switch (R.getResultKind()) { 5538 case LookupResult::Found: 5539 case LookupResult::FoundOverloaded: 5540 case LookupResult::FoundUnresolvedValue: 5541 case LookupResult::Ambiguous: 5542 return IER_Exists; 5543 5544 case LookupResult::NotFound: 5545 return IER_DoesNotExist; 5546 5547 case LookupResult::NotFoundInCurrentInstantiation: 5548 return IER_Dependent; 5549 } 5550 5551 llvm_unreachable("Invalid LookupResult Kind!"); 5552 } 5553 5554 Sema::IfExistsResult 5555 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 5556 bool IsIfExists, CXXScopeSpec &SS, 5557 UnqualifiedId &Name) { 5558 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 5559 5560 // Check for unexpanded parameter packs. 5561 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 5562 collectUnexpandedParameterPacks(SS, Unexpanded); 5563 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 5564 if (!Unexpanded.empty()) { 5565 DiagnoseUnexpandedParameterPacks(KeywordLoc, 5566 IsIfExists? UPPC_IfExists 5567 : UPPC_IfNotExists, 5568 Unexpanded); 5569 return IER_Error; 5570 } 5571 5572 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 5573 } 5574