SemaExprCXX.cpp revision 252723
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" 38using namespace clang; 39using namespace sema; 40 41/// \brief Handle the result of the special case name lookup for inheriting 42/// constructor declarations. 'NS::X::X' and 'NS::X<...>::X' are treated as 43/// constructor names in member using declarations, even if 'X' is not the 44/// name of the corresponding type. 45ParsedType Sema::getInheritingConstructorName(CXXScopeSpec &SS, 46 SourceLocation NameLoc, 47 IdentifierInfo &Name) { 48 NestedNameSpecifier *NNS = SS.getScopeRep(); 49 50 // Convert the nested-name-specifier into a type. 51 QualType Type; 52 switch (NNS->getKind()) { 53 case NestedNameSpecifier::TypeSpec: 54 case NestedNameSpecifier::TypeSpecWithTemplate: 55 Type = QualType(NNS->getAsType(), 0); 56 break; 57 58 case NestedNameSpecifier::Identifier: 59 // Strip off the last layer of the nested-name-specifier and build a 60 // typename type for it. 61 assert(NNS->getAsIdentifier() == &Name && "not a constructor name"); 62 Type = Context.getDependentNameType(ETK_None, NNS->getPrefix(), 63 NNS->getAsIdentifier()); 64 break; 65 66 case NestedNameSpecifier::Global: 67 case NestedNameSpecifier::Namespace: 68 case NestedNameSpecifier::NamespaceAlias: 69 llvm_unreachable("Nested name specifier is not a type for inheriting ctor"); 70 } 71 72 // This reference to the type is located entirely at the location of the 73 // final identifier in the qualified-id. 74 return CreateParsedType(Type, 75 Context.getTrivialTypeSourceInfo(Type, NameLoc)); 76} 77 78ParsedType Sema::getDestructorName(SourceLocation TildeLoc, 79 IdentifierInfo &II, 80 SourceLocation NameLoc, 81 Scope *S, CXXScopeSpec &SS, 82 ParsedType ObjectTypePtr, 83 bool EnteringContext) { 84 // Determine where to perform name lookup. 85 86 // FIXME: This area of the standard is very messy, and the current 87 // wording is rather unclear about which scopes we search for the 88 // destructor name; see core issues 399 and 555. Issue 399 in 89 // particular shows where the current description of destructor name 90 // lookup is completely out of line with existing practice, e.g., 91 // this appears to be ill-formed: 92 // 93 // namespace N { 94 // template <typename T> struct S { 95 // ~S(); 96 // }; 97 // } 98 // 99 // void f(N::S<int>* s) { 100 // s->N::S<int>::~S(); 101 // } 102 // 103 // See also PR6358 and PR6359. 104 // For this reason, we're currently only doing the C++03 version of this 105 // code; the C++0x version has to wait until we get a proper spec. 106 QualType SearchType; 107 DeclContext *LookupCtx = 0; 108 bool isDependent = false; 109 bool LookInScope = false; 110 111 // If we have an object type, it's because we are in a 112 // pseudo-destructor-expression or a member access expression, and 113 // we know what type we're looking for. 114 if (ObjectTypePtr) 115 SearchType = GetTypeFromParser(ObjectTypePtr); 116 117 if (SS.isSet()) { 118 NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 119 120 bool AlreadySearched = false; 121 bool LookAtPrefix = true; 122 // C++ [basic.lookup.qual]p6: 123 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier, 124 // the type-names are looked up as types in the scope designated by the 125 // nested-name-specifier. In a qualified-id of the form: 126 // 127 // ::[opt] nested-name-specifier ~ class-name 128 // 129 // where the nested-name-specifier designates a namespace scope, and in 130 // a qualified-id of the form: 131 // 132 // ::opt nested-name-specifier class-name :: ~ class-name 133 // 134 // the class-names are looked up as types in the scope designated by 135 // the nested-name-specifier. 136 // 137 // Here, we check the first case (completely) and determine whether the 138 // code below is permitted to look at the prefix of the 139 // nested-name-specifier. 140 DeclContext *DC = computeDeclContext(SS, EnteringContext); 141 if (DC && DC->isFileContext()) { 142 AlreadySearched = true; 143 LookupCtx = DC; 144 isDependent = false; 145 } else if (DC && isa<CXXRecordDecl>(DC)) 146 LookAtPrefix = false; 147 148 // The second case from the C++03 rules quoted further above. 149 NestedNameSpecifier *Prefix = 0; 150 if (AlreadySearched) { 151 // Nothing left to do. 152 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) { 153 CXXScopeSpec PrefixSS; 154 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data())); 155 LookupCtx = computeDeclContext(PrefixSS, EnteringContext); 156 isDependent = isDependentScopeSpecifier(PrefixSS); 157 } else if (ObjectTypePtr) { 158 LookupCtx = computeDeclContext(SearchType); 159 isDependent = SearchType->isDependentType(); 160 } else { 161 LookupCtx = computeDeclContext(SS, EnteringContext); 162 isDependent = LookupCtx && LookupCtx->isDependentContext(); 163 } 164 165 LookInScope = false; 166 } else if (ObjectTypePtr) { 167 // C++ [basic.lookup.classref]p3: 168 // If the unqualified-id is ~type-name, the type-name is looked up 169 // in the context of the entire postfix-expression. If the type T 170 // of the object expression is of a class type C, the type-name is 171 // also looked up in the scope of class C. At least one of the 172 // lookups shall find a name that refers to (possibly 173 // cv-qualified) T. 174 LookupCtx = computeDeclContext(SearchType); 175 isDependent = SearchType->isDependentType(); 176 assert((isDependent || !SearchType->isIncompleteType()) && 177 "Caller should have completed object type"); 178 179 LookInScope = true; 180 } else { 181 // Perform lookup into the current scope (only). 182 LookInScope = true; 183 } 184 185 TypeDecl *NonMatchingTypeDecl = 0; 186 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName); 187 for (unsigned Step = 0; Step != 2; ++Step) { 188 // Look for the name first in the computed lookup context (if we 189 // have one) and, if that fails to find a match, in the scope (if 190 // we're allowed to look there). 191 Found.clear(); 192 if (Step == 0 && LookupCtx) 193 LookupQualifiedName(Found, LookupCtx); 194 else if (Step == 1 && LookInScope && S) 195 LookupName(Found, S); 196 else 197 continue; 198 199 // FIXME: Should we be suppressing ambiguities here? 200 if (Found.isAmbiguous()) 201 return ParsedType(); 202 203 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) { 204 QualType T = Context.getTypeDeclType(Type); 205 206 if (SearchType.isNull() || SearchType->isDependentType() || 207 Context.hasSameUnqualifiedType(T, SearchType)) { 208 // We found our type! 209 210 return ParsedType::make(T); 211 } 212 213 if (!SearchType.isNull()) 214 NonMatchingTypeDecl = Type; 215 } 216 217 // If the name that we found is a class template name, and it is 218 // the same name as the template name in the last part of the 219 // nested-name-specifier (if present) or the object type, then 220 // this is the destructor for that class. 221 // FIXME: This is a workaround until we get real drafting for core 222 // issue 399, for which there isn't even an obvious direction. 223 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) { 224 QualType MemberOfType; 225 if (SS.isSet()) { 226 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) { 227 // Figure out the type of the context, if it has one. 228 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) 229 MemberOfType = Context.getTypeDeclType(Record); 230 } 231 } 232 if (MemberOfType.isNull()) 233 MemberOfType = SearchType; 234 235 if (MemberOfType.isNull()) 236 continue; 237 238 // We're referring into a class template specialization. If the 239 // class template we found is the same as the template being 240 // specialized, we found what we are looking for. 241 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) { 242 if (ClassTemplateSpecializationDecl *Spec 243 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) { 244 if (Spec->getSpecializedTemplate()->getCanonicalDecl() == 245 Template->getCanonicalDecl()) 246 return ParsedType::make(MemberOfType); 247 } 248 249 continue; 250 } 251 252 // We're referring to an unresolved class template 253 // specialization. Determine whether we class template we found 254 // is the same as the template being specialized or, if we don't 255 // know which template is being specialized, that it at least 256 // has the same name. 257 if (const TemplateSpecializationType *SpecType 258 = MemberOfType->getAs<TemplateSpecializationType>()) { 259 TemplateName SpecName = SpecType->getTemplateName(); 260 261 // The class template we found is the same template being 262 // specialized. 263 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) { 264 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl()) 265 return ParsedType::make(MemberOfType); 266 267 continue; 268 } 269 270 // The class template we found has the same name as the 271 // (dependent) template name being specialized. 272 if (DependentTemplateName *DepTemplate 273 = SpecName.getAsDependentTemplateName()) { 274 if (DepTemplate->isIdentifier() && 275 DepTemplate->getIdentifier() == Template->getIdentifier()) 276 return ParsedType::make(MemberOfType); 277 278 continue; 279 } 280 } 281 } 282 } 283 284 if (isDependent) { 285 // We didn't find our type, but that's okay: it's dependent 286 // anyway. 287 288 // FIXME: What if we have no nested-name-specifier? 289 QualType T = CheckTypenameType(ETK_None, SourceLocation(), 290 SS.getWithLocInContext(Context), 291 II, NameLoc); 292 return ParsedType::make(T); 293 } 294 295 if (NonMatchingTypeDecl) { 296 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl); 297 Diag(NameLoc, diag::err_destructor_expr_type_mismatch) 298 << T << SearchType; 299 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here) 300 << T; 301 } else if (ObjectTypePtr) 302 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type) 303 << &II; 304 else { 305 SemaDiagnosticBuilder DtorDiag = Diag(NameLoc, 306 diag::err_destructor_class_name); 307 if (S) { 308 const DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity()); 309 if (const CXXRecordDecl *Class = dyn_cast_or_null<CXXRecordDecl>(Ctx)) 310 DtorDiag << FixItHint::CreateReplacement(SourceRange(NameLoc), 311 Class->getNameAsString()); 312 } 313 } 314 315 return ParsedType(); 316} 317 318ParsedType Sema::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) { 319 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType) 320 return ParsedType(); 321 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype 322 && "only get destructor types from declspecs"); 323 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 324 QualType SearchType = GetTypeFromParser(ObjectType); 325 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) { 326 return ParsedType::make(T); 327 } 328 329 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch) 330 << T << SearchType; 331 return ParsedType(); 332} 333 334/// \brief Build a C++ typeid expression with a type operand. 335ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 336 SourceLocation TypeidLoc, 337 TypeSourceInfo *Operand, 338 SourceLocation RParenLoc) { 339 // C++ [expr.typeid]p4: 340 // The top-level cv-qualifiers of the lvalue expression or the type-id 341 // that is the operand of typeid are always ignored. 342 // If the type of the type-id is a class type or a reference to a class 343 // type, the class shall be completely-defined. 344 Qualifiers Quals; 345 QualType T 346 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(), 347 Quals); 348 if (T->getAs<RecordType>() && 349 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 350 return ExprError(); 351 352 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 353 Operand, 354 SourceRange(TypeidLoc, RParenLoc))); 355} 356 357/// \brief Build a C++ typeid expression with an expression operand. 358ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 359 SourceLocation TypeidLoc, 360 Expr *E, 361 SourceLocation RParenLoc) { 362 if (E && !E->isTypeDependent()) { 363 if (E->getType()->isPlaceholderType()) { 364 ExprResult result = CheckPlaceholderExpr(E); 365 if (result.isInvalid()) return ExprError(); 366 E = result.take(); 367 } 368 369 QualType T = E->getType(); 370 if (const RecordType *RecordT = T->getAs<RecordType>()) { 371 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl()); 372 // C++ [expr.typeid]p3: 373 // [...] If the type of the expression is a class type, the class 374 // shall be completely-defined. 375 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 376 return ExprError(); 377 378 // C++ [expr.typeid]p3: 379 // When typeid is applied to an expression other than an glvalue of a 380 // polymorphic class type [...] [the] expression is an unevaluated 381 // operand. [...] 382 if (RecordD->isPolymorphic() && E->isGLValue()) { 383 // The subexpression is potentially evaluated; switch the context 384 // and recheck the subexpression. 385 ExprResult Result = TransformToPotentiallyEvaluated(E); 386 if (Result.isInvalid()) return ExprError(); 387 E = Result.take(); 388 389 // We require a vtable to query the type at run time. 390 MarkVTableUsed(TypeidLoc, RecordD); 391 } 392 } 393 394 // C++ [expr.typeid]p4: 395 // [...] If the type of the type-id is a reference to a possibly 396 // cv-qualified type, the result of the typeid expression refers to a 397 // std::type_info object representing the cv-unqualified referenced 398 // type. 399 Qualifiers Quals; 400 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals); 401 if (!Context.hasSameType(T, UnqualT)) { 402 T = UnqualT; 403 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).take(); 404 } 405 } 406 407 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 408 E, 409 SourceRange(TypeidLoc, RParenLoc))); 410} 411 412/// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression); 413ExprResult 414Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc, 415 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 416 // Find the std::type_info type. 417 if (!getStdNamespace()) 418 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 419 420 if (!CXXTypeInfoDecl) { 421 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info"); 422 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName); 423 LookupQualifiedName(R, getStdNamespace()); 424 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 425 // Microsoft's typeinfo doesn't have type_info in std but in the global 426 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153. 427 if (!CXXTypeInfoDecl && LangOpts.MicrosoftMode) { 428 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 429 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 430 } 431 if (!CXXTypeInfoDecl) 432 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 433 } 434 435 if (!getLangOpts().RTTI) { 436 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti)); 437 } 438 439 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl); 440 441 if (isType) { 442 // The operand is a type; handle it as such. 443 TypeSourceInfo *TInfo = 0; 444 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 445 &TInfo); 446 if (T.isNull()) 447 return ExprError(); 448 449 if (!TInfo) 450 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 451 452 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc); 453 } 454 455 // The operand is an expression. 456 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 457} 458 459/// \brief Build a Microsoft __uuidof expression with a type operand. 460ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 461 SourceLocation TypeidLoc, 462 TypeSourceInfo *Operand, 463 SourceLocation RParenLoc) { 464 if (!Operand->getType()->isDependentType()) { 465 if (!CXXUuidofExpr::GetUuidAttrOfType(Operand->getType())) 466 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 467 } 468 469 // FIXME: add __uuidof semantic analysis for type operand. 470 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 471 Operand, 472 SourceRange(TypeidLoc, RParenLoc))); 473} 474 475/// \brief Build a Microsoft __uuidof expression with an expression operand. 476ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 477 SourceLocation TypeidLoc, 478 Expr *E, 479 SourceLocation RParenLoc) { 480 if (!E->getType()->isDependentType()) { 481 if (!CXXUuidofExpr::GetUuidAttrOfType(E->getType()) && 482 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 483 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 484 } 485 // FIXME: add __uuidof semantic analysis for type operand. 486 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 487 E, 488 SourceRange(TypeidLoc, RParenLoc))); 489} 490 491/// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression); 492ExprResult 493Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc, 494 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 495 // If MSVCGuidDecl has not been cached, do the lookup. 496 if (!MSVCGuidDecl) { 497 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID"); 498 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName); 499 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 500 MSVCGuidDecl = R.getAsSingle<RecordDecl>(); 501 if (!MSVCGuidDecl) 502 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof)); 503 } 504 505 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl); 506 507 if (isType) { 508 // The operand is a type; handle it as such. 509 TypeSourceInfo *TInfo = 0; 510 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 511 &TInfo); 512 if (T.isNull()) 513 return ExprError(); 514 515 if (!TInfo) 516 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 517 518 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc); 519 } 520 521 // The operand is an expression. 522 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 523} 524 525/// ActOnCXXBoolLiteral - Parse {true,false} literals. 526ExprResult 527Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 528 assert((Kind == tok::kw_true || Kind == tok::kw_false) && 529 "Unknown C++ Boolean value!"); 530 return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true, 531 Context.BoolTy, OpLoc)); 532} 533 534/// ActOnCXXNullPtrLiteral - Parse 'nullptr'. 535ExprResult 536Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) { 537 return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc)); 538} 539 540/// ActOnCXXThrow - Parse throw expressions. 541ExprResult 542Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) { 543 bool IsThrownVarInScope = false; 544 if (Ex) { 545 // C++0x [class.copymove]p31: 546 // When certain criteria are met, an implementation is allowed to omit the 547 // copy/move construction of a class object [...] 548 // 549 // - in a throw-expression, when the operand is the name of a 550 // non-volatile automatic object (other than a function or catch- 551 // clause parameter) whose scope does not extend beyond the end of the 552 // innermost enclosing try-block (if there is one), the copy/move 553 // operation from the operand to the exception object (15.1) can be 554 // omitted by constructing the automatic object directly into the 555 // exception object 556 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens())) 557 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 558 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) { 559 for( ; S; S = S->getParent()) { 560 if (S->isDeclScope(Var)) { 561 IsThrownVarInScope = true; 562 break; 563 } 564 565 if (S->getFlags() & 566 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope | 567 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope | 568 Scope::TryScope)) 569 break; 570 } 571 } 572 } 573 } 574 575 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope); 576} 577 578ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex, 579 bool IsThrownVarInScope) { 580 // Don't report an error if 'throw' is used in system headers. 581 if (!getLangOpts().CXXExceptions && 582 !getSourceManager().isInSystemHeader(OpLoc)) 583 Diag(OpLoc, diag::err_exceptions_disabled) << "throw"; 584 585 if (Ex && !Ex->isTypeDependent()) { 586 ExprResult ExRes = CheckCXXThrowOperand(OpLoc, Ex, IsThrownVarInScope); 587 if (ExRes.isInvalid()) 588 return ExprError(); 589 Ex = ExRes.take(); 590 } 591 592 return Owned(new (Context) CXXThrowExpr(Ex, Context.VoidTy, OpLoc, 593 IsThrownVarInScope)); 594} 595 596/// CheckCXXThrowOperand - Validate the operand of a throw. 597ExprResult Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *E, 598 bool IsThrownVarInScope) { 599 // C++ [except.throw]p3: 600 // A throw-expression initializes a temporary object, called the exception 601 // object, the type of which is determined by removing any top-level 602 // cv-qualifiers from the static type of the operand of throw and adjusting 603 // the type from "array of T" or "function returning T" to "pointer to T" 604 // or "pointer to function returning T", [...] 605 if (E->getType().hasQualifiers()) 606 E = ImpCastExprToType(E, E->getType().getUnqualifiedType(), CK_NoOp, 607 E->getValueKind()).take(); 608 609 ExprResult Res = DefaultFunctionArrayConversion(E); 610 if (Res.isInvalid()) 611 return ExprError(); 612 E = Res.take(); 613 614 // If the type of the exception would be an incomplete type or a pointer 615 // to an incomplete type other than (cv) void the program is ill-formed. 616 QualType Ty = E->getType(); 617 bool isPointer = false; 618 if (const PointerType* Ptr = Ty->getAs<PointerType>()) { 619 Ty = Ptr->getPointeeType(); 620 isPointer = true; 621 } 622 if (!isPointer || !Ty->isVoidType()) { 623 if (RequireCompleteType(ThrowLoc, Ty, 624 isPointer? diag::err_throw_incomplete_ptr 625 : diag::err_throw_incomplete, 626 E->getSourceRange())) 627 return ExprError(); 628 629 if (RequireNonAbstractType(ThrowLoc, E->getType(), 630 diag::err_throw_abstract_type, E)) 631 return ExprError(); 632 } 633 634 // Initialize the exception result. This implicitly weeds out 635 // abstract types or types with inaccessible copy constructors. 636 637 // C++0x [class.copymove]p31: 638 // When certain criteria are met, an implementation is allowed to omit the 639 // copy/move construction of a class object [...] 640 // 641 // - in a throw-expression, when the operand is the name of a 642 // non-volatile automatic object (other than a function or catch-clause 643 // parameter) whose scope does not extend beyond the end of the 644 // innermost enclosing try-block (if there is one), the copy/move 645 // operation from the operand to the exception object (15.1) can be 646 // omitted by constructing the automatic object directly into the 647 // exception object 648 const VarDecl *NRVOVariable = 0; 649 if (IsThrownVarInScope) 650 NRVOVariable = getCopyElisionCandidate(QualType(), E, false); 651 652 InitializedEntity Entity = 653 InitializedEntity::InitializeException(ThrowLoc, E->getType(), 654 /*NRVO=*/NRVOVariable != 0); 655 Res = PerformMoveOrCopyInitialization(Entity, NRVOVariable, 656 QualType(), E, 657 IsThrownVarInScope); 658 if (Res.isInvalid()) 659 return ExprError(); 660 E = Res.take(); 661 662 // If the exception has class type, we need additional handling. 663 const RecordType *RecordTy = Ty->getAs<RecordType>(); 664 if (!RecordTy) 665 return Owned(E); 666 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl()); 667 668 // If we are throwing a polymorphic class type or pointer thereof, 669 // exception handling will make use of the vtable. 670 MarkVTableUsed(ThrowLoc, RD); 671 672 // If a pointer is thrown, the referenced object will not be destroyed. 673 if (isPointer) 674 return Owned(E); 675 676 // If the class has a destructor, we must be able to call it. 677 if (RD->hasIrrelevantDestructor()) 678 return Owned(E); 679 680 CXXDestructorDecl *Destructor = LookupDestructor(RD); 681 if (!Destructor) 682 return Owned(E); 683 684 MarkFunctionReferenced(E->getExprLoc(), Destructor); 685 CheckDestructorAccess(E->getExprLoc(), Destructor, 686 PDiag(diag::err_access_dtor_exception) << Ty); 687 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc())) 688 return ExprError(); 689 return Owned(E); 690} 691 692QualType Sema::getCurrentThisType() { 693 DeclContext *DC = getFunctionLevelDeclContext(); 694 QualType ThisTy = CXXThisTypeOverride; 695 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) { 696 if (method && method->isInstance()) 697 ThisTy = method->getThisType(Context); 698 } 699 700 return ThisTy; 701} 702 703Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S, 704 Decl *ContextDecl, 705 unsigned CXXThisTypeQuals, 706 bool Enabled) 707 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false) 708{ 709 if (!Enabled || !ContextDecl) 710 return; 711 712 CXXRecordDecl *Record = 0; 713 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl)) 714 Record = Template->getTemplatedDecl(); 715 else 716 Record = cast<CXXRecordDecl>(ContextDecl); 717 718 S.CXXThisTypeOverride 719 = S.Context.getPointerType( 720 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals)); 721 722 this->Enabled = true; 723} 724 725 726Sema::CXXThisScopeRAII::~CXXThisScopeRAII() { 727 if (Enabled) { 728 S.CXXThisTypeOverride = OldCXXThisTypeOverride; 729 } 730} 731 732static Expr *captureThis(ASTContext &Context, RecordDecl *RD, 733 QualType ThisTy, SourceLocation Loc) { 734 FieldDecl *Field 735 = FieldDecl::Create(Context, RD, Loc, Loc, 0, ThisTy, 736 Context.getTrivialTypeSourceInfo(ThisTy, Loc), 737 0, false, ICIS_NoInit); 738 Field->setImplicit(true); 739 Field->setAccess(AS_private); 740 RD->addDecl(Field); 741 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit*/true); 742} 743 744void Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit) { 745 // We don't need to capture this in an unevaluated context. 746 if (isUnevaluatedContext() && !Explicit) 747 return; 748 749 // Otherwise, check that we can capture 'this'. 750 unsigned NumClosures = 0; 751 for (unsigned idx = FunctionScopes.size() - 1; idx != 0; idx--) { 752 if (CapturingScopeInfo *CSI = 753 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) { 754 if (CSI->CXXThisCaptureIndex != 0) { 755 // 'this' is already being captured; there isn't anything more to do. 756 break; 757 } 758 759 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref || 760 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval || 761 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block || 762 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion || 763 Explicit) { 764 // This closure can capture 'this'; continue looking upwards. 765 NumClosures++; 766 Explicit = false; 767 continue; 768 } 769 // This context can't implicitly capture 'this'; fail out. 770 Diag(Loc, diag::err_this_capture) << Explicit; 771 return; 772 } 773 break; 774 } 775 776 // Mark that we're implicitly capturing 'this' in all the scopes we skipped. 777 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated 778 // contexts. 779 for (unsigned idx = FunctionScopes.size() - 1; 780 NumClosures; --idx, --NumClosures) { 781 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]); 782 Expr *ThisExpr = 0; 783 QualType ThisTy = getCurrentThisType(); 784 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) 785 // For lambda expressions, build a field and an initializing expression. 786 ThisExpr = captureThis(Context, LSI->Lambda, ThisTy, Loc); 787 else if (CapturedRegionScopeInfo *RSI 788 = dyn_cast<CapturedRegionScopeInfo>(FunctionScopes[idx])) 789 ThisExpr = captureThis(Context, RSI->TheRecordDecl, ThisTy, Loc); 790 791 bool isNested = NumClosures > 1; 792 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr); 793 } 794} 795 796ExprResult Sema::ActOnCXXThis(SourceLocation Loc) { 797 /// C++ 9.3.2: In the body of a non-static member function, the keyword this 798 /// is a non-lvalue expression whose value is the address of the object for 799 /// which the function is called. 800 801 QualType ThisTy = getCurrentThisType(); 802 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use); 803 804 CheckCXXThisCapture(Loc); 805 return Owned(new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false)); 806} 807 808bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) { 809 // If we're outside the body of a member function, then we'll have a specified 810 // type for 'this'. 811 if (CXXThisTypeOverride.isNull()) 812 return false; 813 814 // Determine whether we're looking into a class that's currently being 815 // defined. 816 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl(); 817 return Class && Class->isBeingDefined(); 818} 819 820ExprResult 821Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep, 822 SourceLocation LParenLoc, 823 MultiExprArg exprs, 824 SourceLocation RParenLoc) { 825 if (!TypeRep) 826 return ExprError(); 827 828 TypeSourceInfo *TInfo; 829 QualType Ty = GetTypeFromParser(TypeRep, &TInfo); 830 if (!TInfo) 831 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation()); 832 833 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc); 834} 835 836/// ActOnCXXTypeConstructExpr - Parse construction of a specified type. 837/// Can be interpreted either as function-style casting ("int(x)") 838/// or class type construction ("ClassType(x,y,z)") 839/// or creation of a value-initialized type ("int()"). 840ExprResult 841Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, 842 SourceLocation LParenLoc, 843 MultiExprArg Exprs, 844 SourceLocation RParenLoc) { 845 QualType Ty = TInfo->getType(); 846 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); 847 848 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) { 849 return Owned(CXXUnresolvedConstructExpr::Create(Context, TInfo, 850 LParenLoc, 851 Exprs, 852 RParenLoc)); 853 } 854 855 bool ListInitialization = LParenLoc.isInvalid(); 856 assert((!ListInitialization || (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0]))) 857 && "List initialization must have initializer list as expression."); 858 SourceRange FullRange = SourceRange(TyBeginLoc, 859 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc); 860 861 // C++ [expr.type.conv]p1: 862 // If the expression list is a single expression, the type conversion 863 // expression is equivalent (in definedness, and if defined in meaning) to the 864 // corresponding cast expression. 865 if (Exprs.size() == 1 && !ListInitialization) { 866 Expr *Arg = Exprs[0]; 867 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc); 868 } 869 870 QualType ElemTy = Ty; 871 if (Ty->isArrayType()) { 872 if (!ListInitialization) 873 return ExprError(Diag(TyBeginLoc, 874 diag::err_value_init_for_array_type) << FullRange); 875 ElemTy = Context.getBaseElementType(Ty); 876 } 877 878 if (!Ty->isVoidType() && 879 RequireCompleteType(TyBeginLoc, ElemTy, 880 diag::err_invalid_incomplete_type_use, FullRange)) 881 return ExprError(); 882 883 if (RequireNonAbstractType(TyBeginLoc, Ty, 884 diag::err_allocation_of_abstract_type)) 885 return ExprError(); 886 887 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo); 888 InitializationKind Kind = 889 Exprs.size() ? ListInitialization 890 ? InitializationKind::CreateDirectList(TyBeginLoc) 891 : InitializationKind::CreateDirect(TyBeginLoc, LParenLoc, RParenLoc) 892 : InitializationKind::CreateValue(TyBeginLoc, LParenLoc, RParenLoc); 893 InitializationSequence InitSeq(*this, Entity, Kind, Exprs); 894 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs); 895 896 if (!Result.isInvalid() && ListInitialization && 897 isa<InitListExpr>(Result.get())) { 898 // If the list-initialization doesn't involve a constructor call, we'll get 899 // the initializer-list (with corrected type) back, but that's not what we 900 // want, since it will be treated as an initializer list in further 901 // processing. Explicitly insert a cast here. 902 InitListExpr *List = cast<InitListExpr>(Result.take()); 903 Result = Owned(CXXFunctionalCastExpr::Create(Context, List->getType(), 904 Expr::getValueKindForType(TInfo->getType()), 905 TInfo, TyBeginLoc, CK_NoOp, 906 List, /*Path=*/0, RParenLoc)); 907 } 908 909 // FIXME: Improve AST representation? 910 return Result; 911} 912 913/// doesUsualArrayDeleteWantSize - Answers whether the usual 914/// operator delete[] for the given type has a size_t parameter. 915static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc, 916 QualType allocType) { 917 const RecordType *record = 918 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>(); 919 if (!record) return false; 920 921 // Try to find an operator delete[] in class scope. 922 923 DeclarationName deleteName = 924 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete); 925 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName); 926 S.LookupQualifiedName(ops, record->getDecl()); 927 928 // We're just doing this for information. 929 ops.suppressDiagnostics(); 930 931 // Very likely: there's no operator delete[]. 932 if (ops.empty()) return false; 933 934 // If it's ambiguous, it should be illegal to call operator delete[] 935 // on this thing, so it doesn't matter if we allocate extra space or not. 936 if (ops.isAmbiguous()) return false; 937 938 LookupResult::Filter filter = ops.makeFilter(); 939 while (filter.hasNext()) { 940 NamedDecl *del = filter.next()->getUnderlyingDecl(); 941 942 // C++0x [basic.stc.dynamic.deallocation]p2: 943 // A template instance is never a usual deallocation function, 944 // regardless of its signature. 945 if (isa<FunctionTemplateDecl>(del)) { 946 filter.erase(); 947 continue; 948 } 949 950 // C++0x [basic.stc.dynamic.deallocation]p2: 951 // If class T does not declare [an operator delete[] with one 952 // parameter] but does declare a member deallocation function 953 // named operator delete[] with exactly two parameters, the 954 // second of which has type std::size_t, then this function 955 // is a usual deallocation function. 956 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) { 957 filter.erase(); 958 continue; 959 } 960 } 961 filter.done(); 962 963 if (!ops.isSingleResult()) return false; 964 965 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl()); 966 return (del->getNumParams() == 2); 967} 968 969/// \brief Parsed a C++ 'new' expression (C++ 5.3.4). 970/// 971/// E.g.: 972/// @code new (memory) int[size][4] @endcode 973/// or 974/// @code ::new Foo(23, "hello") @endcode 975/// 976/// \param StartLoc The first location of the expression. 977/// \param UseGlobal True if 'new' was prefixed with '::'. 978/// \param PlacementLParen Opening paren of the placement arguments. 979/// \param PlacementArgs Placement new arguments. 980/// \param PlacementRParen Closing paren of the placement arguments. 981/// \param TypeIdParens If the type is in parens, the source range. 982/// \param D The type to be allocated, as well as array dimensions. 983/// \param Initializer The initializing expression or initializer-list, or null 984/// if there is none. 985ExprResult 986Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal, 987 SourceLocation PlacementLParen, MultiExprArg PlacementArgs, 988 SourceLocation PlacementRParen, SourceRange TypeIdParens, 989 Declarator &D, Expr *Initializer) { 990 bool TypeContainsAuto = D.getDeclSpec().containsPlaceholderType(); 991 992 Expr *ArraySize = 0; 993 // If the specified type is an array, unwrap it and save the expression. 994 if (D.getNumTypeObjects() > 0 && 995 D.getTypeObject(0).Kind == DeclaratorChunk::Array) { 996 DeclaratorChunk &Chunk = D.getTypeObject(0); 997 if (TypeContainsAuto) 998 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto) 999 << D.getSourceRange()); 1000 if (Chunk.Arr.hasStatic) 1001 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new) 1002 << D.getSourceRange()); 1003 if (!Chunk.Arr.NumElts) 1004 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size) 1005 << D.getSourceRange()); 1006 1007 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts); 1008 D.DropFirstTypeObject(); 1009 } 1010 1011 // Every dimension shall be of constant size. 1012 if (ArraySize) { 1013 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) { 1014 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array) 1015 break; 1016 1017 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr; 1018 if (Expr *NumElts = (Expr *)Array.NumElts) { 1019 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) { 1020 Array.NumElts 1021 = VerifyIntegerConstantExpression(NumElts, 0, 1022 diag::err_new_array_nonconst) 1023 .take(); 1024 if (!Array.NumElts) 1025 return ExprError(); 1026 } 1027 } 1028 } 1029 } 1030 1031 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/0); 1032 QualType AllocType = TInfo->getType(); 1033 if (D.isInvalidType()) 1034 return ExprError(); 1035 1036 SourceRange DirectInitRange; 1037 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) 1038 DirectInitRange = List->getSourceRange(); 1039 1040 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal, 1041 PlacementLParen, 1042 PlacementArgs, 1043 PlacementRParen, 1044 TypeIdParens, 1045 AllocType, 1046 TInfo, 1047 ArraySize, 1048 DirectInitRange, 1049 Initializer, 1050 TypeContainsAuto); 1051} 1052 1053static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style, 1054 Expr *Init) { 1055 if (!Init) 1056 return true; 1057 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init)) 1058 return PLE->getNumExprs() == 0; 1059 if (isa<ImplicitValueInitExpr>(Init)) 1060 return true; 1061 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) 1062 return !CCE->isListInitialization() && 1063 CCE->getConstructor()->isDefaultConstructor(); 1064 else if (Style == CXXNewExpr::ListInit) { 1065 assert(isa<InitListExpr>(Init) && 1066 "Shouldn't create list CXXConstructExprs for arrays."); 1067 return true; 1068 } 1069 return false; 1070} 1071 1072ExprResult 1073Sema::BuildCXXNew(SourceRange Range, bool UseGlobal, 1074 SourceLocation PlacementLParen, 1075 MultiExprArg PlacementArgs, 1076 SourceLocation PlacementRParen, 1077 SourceRange TypeIdParens, 1078 QualType AllocType, 1079 TypeSourceInfo *AllocTypeInfo, 1080 Expr *ArraySize, 1081 SourceRange DirectInitRange, 1082 Expr *Initializer, 1083 bool TypeMayContainAuto) { 1084 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange(); 1085 SourceLocation StartLoc = Range.getBegin(); 1086 1087 CXXNewExpr::InitializationStyle initStyle; 1088 if (DirectInitRange.isValid()) { 1089 assert(Initializer && "Have parens but no initializer."); 1090 initStyle = CXXNewExpr::CallInit; 1091 } else if (Initializer && isa<InitListExpr>(Initializer)) 1092 initStyle = CXXNewExpr::ListInit; 1093 else { 1094 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) || 1095 isa<CXXConstructExpr>(Initializer)) && 1096 "Initializer expression that cannot have been implicitly created."); 1097 initStyle = CXXNewExpr::NoInit; 1098 } 1099 1100 Expr **Inits = &Initializer; 1101 unsigned NumInits = Initializer ? 1 : 0; 1102 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) { 1103 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init"); 1104 Inits = List->getExprs(); 1105 NumInits = List->getNumExprs(); 1106 } 1107 1108 // Determine whether we've already built the initializer. 1109 bool HaveCompleteInit = false; 1110 if (Initializer && isa<CXXConstructExpr>(Initializer) && 1111 !isa<CXXTemporaryObjectExpr>(Initializer)) 1112 HaveCompleteInit = true; 1113 else if (Initializer && isa<ImplicitValueInitExpr>(Initializer)) 1114 HaveCompleteInit = true; 1115 1116 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 1117 if (TypeMayContainAuto && AllocType->isUndeducedType()) { 1118 if (initStyle == CXXNewExpr::NoInit || NumInits == 0) 1119 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg) 1120 << AllocType << TypeRange); 1121 if (initStyle == CXXNewExpr::ListInit) 1122 return ExprError(Diag(Inits[0]->getLocStart(), 1123 diag::err_auto_new_requires_parens) 1124 << AllocType << TypeRange); 1125 if (NumInits > 1) { 1126 Expr *FirstBad = Inits[1]; 1127 return ExprError(Diag(FirstBad->getLocStart(), 1128 diag::err_auto_new_ctor_multiple_expressions) 1129 << AllocType << TypeRange); 1130 } 1131 Expr *Deduce = Inits[0]; 1132 QualType DeducedType; 1133 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed) 1134 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure) 1135 << AllocType << Deduce->getType() 1136 << TypeRange << Deduce->getSourceRange()); 1137 if (DeducedType.isNull()) 1138 return ExprError(); 1139 AllocType = DeducedType; 1140 } 1141 1142 // Per C++0x [expr.new]p5, the type being constructed may be a 1143 // typedef of an array type. 1144 if (!ArraySize) { 1145 if (const ConstantArrayType *Array 1146 = Context.getAsConstantArrayType(AllocType)) { 1147 ArraySize = IntegerLiteral::Create(Context, Array->getSize(), 1148 Context.getSizeType(), 1149 TypeRange.getEnd()); 1150 AllocType = Array->getElementType(); 1151 } 1152 } 1153 1154 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange)) 1155 return ExprError(); 1156 1157 if (initStyle == CXXNewExpr::ListInit && isStdInitializerList(AllocType, 0)) { 1158 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(), 1159 diag::warn_dangling_std_initializer_list) 1160 << /*at end of FE*/0 << Inits[0]->getSourceRange(); 1161 } 1162 1163 // In ARC, infer 'retaining' for the allocated 1164 if (getLangOpts().ObjCAutoRefCount && 1165 AllocType.getObjCLifetime() == Qualifiers::OCL_None && 1166 AllocType->isObjCLifetimeType()) { 1167 AllocType = Context.getLifetimeQualifiedType(AllocType, 1168 AllocType->getObjCARCImplicitLifetime()); 1169 } 1170 1171 QualType ResultType = Context.getPointerType(AllocType); 1172 1173 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) { 1174 ExprResult result = CheckPlaceholderExpr(ArraySize); 1175 if (result.isInvalid()) return ExprError(); 1176 ArraySize = result.take(); 1177 } 1178 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have 1179 // integral or enumeration type with a non-negative value." 1180 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped 1181 // enumeration type, or a class type for which a single non-explicit 1182 // conversion function to integral or unscoped enumeration type exists. 1183 if (ArraySize && !ArraySize->isTypeDependent()) { 1184 class SizeConvertDiagnoser : public ICEConvertDiagnoser { 1185 Expr *ArraySize; 1186 1187 public: 1188 SizeConvertDiagnoser(Expr *ArraySize) 1189 : ICEConvertDiagnoser(false, false), ArraySize(ArraySize) { } 1190 1191 virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc, 1192 QualType T) { 1193 return S.Diag(Loc, diag::err_array_size_not_integral) 1194 << S.getLangOpts().CPlusPlus11 << T; 1195 } 1196 1197 virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc, 1198 QualType T) { 1199 return S.Diag(Loc, diag::err_array_size_incomplete_type) 1200 << T << ArraySize->getSourceRange(); 1201 } 1202 1203 virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, 1204 SourceLocation Loc, 1205 QualType T, 1206 QualType ConvTy) { 1207 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy; 1208 } 1209 1210 virtual DiagnosticBuilder noteExplicitConv(Sema &S, 1211 CXXConversionDecl *Conv, 1212 QualType ConvTy) { 1213 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion) 1214 << ConvTy->isEnumeralType() << ConvTy; 1215 } 1216 1217 virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc, 1218 QualType T) { 1219 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T; 1220 } 1221 1222 virtual DiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv, 1223 QualType ConvTy) { 1224 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion) 1225 << ConvTy->isEnumeralType() << ConvTy; 1226 } 1227 1228 virtual DiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc, 1229 QualType T, 1230 QualType ConvTy) { 1231 return S.Diag(Loc, 1232 S.getLangOpts().CPlusPlus11 1233 ? diag::warn_cxx98_compat_array_size_conversion 1234 : diag::ext_array_size_conversion) 1235 << T << ConvTy->isEnumeralType() << ConvTy; 1236 } 1237 } SizeDiagnoser(ArraySize); 1238 1239 ExprResult ConvertedSize 1240 = ConvertToIntegralOrEnumerationType(StartLoc, ArraySize, SizeDiagnoser, 1241 /*AllowScopedEnumerations*/ false); 1242 if (ConvertedSize.isInvalid()) 1243 return ExprError(); 1244 1245 ArraySize = ConvertedSize.take(); 1246 QualType SizeType = ArraySize->getType(); 1247 if (!SizeType->isIntegralOrUnscopedEnumerationType()) 1248 return ExprError(); 1249 1250 // C++98 [expr.new]p7: 1251 // The expression in a direct-new-declarator shall have integral type 1252 // with a non-negative value. 1253 // 1254 // Let's see if this is a constant < 0. If so, we reject it out of 1255 // hand. Otherwise, if it's not a constant, we must have an unparenthesized 1256 // array type. 1257 // 1258 // Note: such a construct has well-defined semantics in C++11: it throws 1259 // std::bad_array_new_length. 1260 if (!ArraySize->isValueDependent()) { 1261 llvm::APSInt Value; 1262 // We've already performed any required implicit conversion to integer or 1263 // unscoped enumeration type. 1264 if (ArraySize->isIntegerConstantExpr(Value, Context)) { 1265 if (Value < llvm::APSInt( 1266 llvm::APInt::getNullValue(Value.getBitWidth()), 1267 Value.isUnsigned())) { 1268 if (getLangOpts().CPlusPlus11) 1269 Diag(ArraySize->getLocStart(), 1270 diag::warn_typecheck_negative_array_new_size) 1271 << ArraySize->getSourceRange(); 1272 else 1273 return ExprError(Diag(ArraySize->getLocStart(), 1274 diag::err_typecheck_negative_array_size) 1275 << ArraySize->getSourceRange()); 1276 } else if (!AllocType->isDependentType()) { 1277 unsigned ActiveSizeBits = 1278 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value); 1279 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 1280 if (getLangOpts().CPlusPlus11) 1281 Diag(ArraySize->getLocStart(), 1282 diag::warn_array_new_too_large) 1283 << Value.toString(10) 1284 << ArraySize->getSourceRange(); 1285 else 1286 return ExprError(Diag(ArraySize->getLocStart(), 1287 diag::err_array_too_large) 1288 << Value.toString(10) 1289 << ArraySize->getSourceRange()); 1290 } 1291 } 1292 } else if (TypeIdParens.isValid()) { 1293 // Can't have dynamic array size when the type-id is in parentheses. 1294 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst) 1295 << ArraySize->getSourceRange() 1296 << FixItHint::CreateRemoval(TypeIdParens.getBegin()) 1297 << FixItHint::CreateRemoval(TypeIdParens.getEnd()); 1298 1299 TypeIdParens = SourceRange(); 1300 } 1301 } 1302 1303 // Note that we do *not* convert the argument in any way. It can 1304 // be signed, larger than size_t, whatever. 1305 } 1306 1307 FunctionDecl *OperatorNew = 0; 1308 FunctionDecl *OperatorDelete = 0; 1309 Expr **PlaceArgs = PlacementArgs.data(); 1310 unsigned NumPlaceArgs = PlacementArgs.size(); 1311 1312 if (!AllocType->isDependentType() && 1313 !Expr::hasAnyTypeDependentArguments( 1314 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs)) && 1315 FindAllocationFunctions(StartLoc, 1316 SourceRange(PlacementLParen, PlacementRParen), 1317 UseGlobal, AllocType, ArraySize, PlaceArgs, 1318 NumPlaceArgs, OperatorNew, OperatorDelete)) 1319 return ExprError(); 1320 1321 // If this is an array allocation, compute whether the usual array 1322 // deallocation function for the type has a size_t parameter. 1323 bool UsualArrayDeleteWantsSize = false; 1324 if (ArraySize && !AllocType->isDependentType()) 1325 UsualArrayDeleteWantsSize 1326 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType); 1327 1328 SmallVector<Expr *, 8> AllPlaceArgs; 1329 if (OperatorNew) { 1330 // Add default arguments, if any. 1331 const FunctionProtoType *Proto = 1332 OperatorNew->getType()->getAs<FunctionProtoType>(); 1333 VariadicCallType CallType = 1334 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 1335 1336 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, 1337 Proto, 1, PlaceArgs, NumPlaceArgs, 1338 AllPlaceArgs, CallType)) 1339 return ExprError(); 1340 1341 NumPlaceArgs = AllPlaceArgs.size(); 1342 if (NumPlaceArgs > 0) 1343 PlaceArgs = &AllPlaceArgs[0]; 1344 1345 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, 1346 PlaceArgs, NumPlaceArgs); 1347 1348 // FIXME: Missing call to CheckFunctionCall or equivalent 1349 } 1350 1351 // Warn if the type is over-aligned and is being allocated by global operator 1352 // new. 1353 if (NumPlaceArgs == 0 && OperatorNew && 1354 (OperatorNew->isImplicit() || 1355 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1356 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1357 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1358 if (Align > SuitableAlign) 1359 Diag(StartLoc, diag::warn_overaligned_type) 1360 << AllocType 1361 << unsigned(Align / Context.getCharWidth()) 1362 << unsigned(SuitableAlign / Context.getCharWidth()); 1363 } 1364 } 1365 1366 QualType InitType = AllocType; 1367 // Array 'new' can't have any initializers except empty parentheses. 1368 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1369 // dialect distinction. 1370 if (ResultType->isArrayType() || ArraySize) { 1371 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1372 SourceRange InitRange(Inits[0]->getLocStart(), 1373 Inits[NumInits - 1]->getLocEnd()); 1374 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1375 return ExprError(); 1376 } 1377 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1378 // We do the initialization typechecking against the array type 1379 // corresponding to the number of initializers + 1 (to also check 1380 // default-initialization). 1381 unsigned NumElements = ILE->getNumInits() + 1; 1382 InitType = Context.getConstantArrayType(AllocType, 1383 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1384 ArrayType::Normal, 0); 1385 } 1386 } 1387 1388 // If we can perform the initialization, and we've not already done so, 1389 // do it now. 1390 if (!AllocType->isDependentType() && 1391 !Expr::hasAnyTypeDependentArguments( 1392 llvm::makeArrayRef(Inits, NumInits)) && 1393 !HaveCompleteInit) { 1394 // C++11 [expr.new]p15: 1395 // A new-expression that creates an object of type T initializes that 1396 // object as follows: 1397 InitializationKind Kind 1398 // - If the new-initializer is omitted, the object is default- 1399 // initialized (8.5); if no initialization is performed, 1400 // the object has indeterminate value 1401 = initStyle == CXXNewExpr::NoInit 1402 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1403 // - Otherwise, the new-initializer is interpreted according to the 1404 // initialization rules of 8.5 for direct-initialization. 1405 : initStyle == CXXNewExpr::ListInit 1406 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1407 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1408 DirectInitRange.getBegin(), 1409 DirectInitRange.getEnd()); 1410 1411 InitializedEntity Entity 1412 = InitializedEntity::InitializeNew(StartLoc, InitType); 1413 InitializationSequence InitSeq(*this, Entity, Kind, MultiExprArg(Inits, NumInits)); 1414 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1415 MultiExprArg(Inits, NumInits)); 1416 if (FullInit.isInvalid()) 1417 return ExprError(); 1418 1419 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1420 // we don't want the initialized object to be destructed. 1421 if (CXXBindTemporaryExpr *Binder = 1422 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1423 FullInit = Owned(Binder->getSubExpr()); 1424 1425 Initializer = FullInit.take(); 1426 } 1427 1428 // Mark the new and delete operators as referenced. 1429 if (OperatorNew) { 1430 if (DiagnoseUseOfDecl(OperatorNew, StartLoc)) 1431 return ExprError(); 1432 MarkFunctionReferenced(StartLoc, OperatorNew); 1433 } 1434 if (OperatorDelete) { 1435 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc)) 1436 return ExprError(); 1437 MarkFunctionReferenced(StartLoc, OperatorDelete); 1438 } 1439 1440 // C++0x [expr.new]p17: 1441 // If the new expression creates an array of objects of class type, 1442 // access and ambiguity control are done for the destructor. 1443 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1444 if (ArraySize && !BaseAllocType->isDependentType()) { 1445 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) { 1446 if (CXXDestructorDecl *dtor = LookupDestructor( 1447 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) { 1448 MarkFunctionReferenced(StartLoc, dtor); 1449 CheckDestructorAccess(StartLoc, dtor, 1450 PDiag(diag::err_access_dtor) 1451 << BaseAllocType); 1452 if (DiagnoseUseOfDecl(dtor, StartLoc)) 1453 return ExprError(); 1454 } 1455 } 1456 } 1457 1458 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1459 OperatorDelete, 1460 UsualArrayDeleteWantsSize, 1461 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs), 1462 TypeIdParens, 1463 ArraySize, initStyle, Initializer, 1464 ResultType, AllocTypeInfo, 1465 Range, DirectInitRange)); 1466} 1467 1468/// \brief Checks that a type is suitable as the allocated type 1469/// in a new-expression. 1470bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1471 SourceRange R) { 1472 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1473 // abstract class type or array thereof. 1474 if (AllocType->isFunctionType()) 1475 return Diag(Loc, diag::err_bad_new_type) 1476 << AllocType << 0 << R; 1477 else if (AllocType->isReferenceType()) 1478 return Diag(Loc, diag::err_bad_new_type) 1479 << AllocType << 1 << R; 1480 else if (!AllocType->isDependentType() && 1481 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R)) 1482 return true; 1483 else if (RequireNonAbstractType(Loc, AllocType, 1484 diag::err_allocation_of_abstract_type)) 1485 return true; 1486 else if (AllocType->isVariablyModifiedType()) 1487 return Diag(Loc, diag::err_variably_modified_new_type) 1488 << AllocType; 1489 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1490 return Diag(Loc, diag::err_address_space_qualified_new) 1491 << AllocType.getUnqualifiedType() << AddressSpace; 1492 else if (getLangOpts().ObjCAutoRefCount) { 1493 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1494 QualType BaseAllocType = Context.getBaseElementType(AT); 1495 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1496 BaseAllocType->isObjCLifetimeType()) 1497 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1498 << BaseAllocType; 1499 } 1500 } 1501 1502 return false; 1503} 1504 1505/// \brief Determine whether the given function is a non-placement 1506/// deallocation function. 1507static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1508 if (FD->isInvalidDecl()) 1509 return false; 1510 1511 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1512 return Method->isUsualDeallocationFunction(); 1513 1514 return ((FD->getOverloadedOperator() == OO_Delete || 1515 FD->getOverloadedOperator() == OO_Array_Delete) && 1516 FD->getNumParams() == 1); 1517} 1518 1519/// FindAllocationFunctions - Finds the overloads of operator new and delete 1520/// that are appropriate for the allocation. 1521bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1522 bool UseGlobal, QualType AllocType, 1523 bool IsArray, Expr **PlaceArgs, 1524 unsigned NumPlaceArgs, 1525 FunctionDecl *&OperatorNew, 1526 FunctionDecl *&OperatorDelete) { 1527 // --- Choosing an allocation function --- 1528 // C++ 5.3.4p8 - 14 & 18 1529 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1530 // in the scope of the allocated class. 1531 // 2) If an array size is given, look for operator new[], else look for 1532 // operator new. 1533 // 3) The first argument is always size_t. Append the arguments from the 1534 // placement form. 1535 1536 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1537 // We don't care about the actual value of this argument. 1538 // FIXME: Should the Sema create the expression and embed it in the syntax 1539 // tree? Or should the consumer just recalculate the value? 1540 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1541 Context.getTargetInfo().getPointerWidth(0)), 1542 Context.getSizeType(), 1543 SourceLocation()); 1544 AllocArgs[0] = &Size; 1545 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1546 1547 // C++ [expr.new]p8: 1548 // If the allocated type is a non-array type, the allocation 1549 // function's name is operator new and the deallocation function's 1550 // name is operator delete. If the allocated type is an array 1551 // type, the allocation function's name is operator new[] and the 1552 // deallocation function's name is operator delete[]. 1553 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1554 IsArray ? OO_Array_New : OO_New); 1555 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1556 IsArray ? OO_Array_Delete : OO_Delete); 1557 1558 QualType AllocElemType = Context.getBaseElementType(AllocType); 1559 1560 if (AllocElemType->isRecordType() && !UseGlobal) { 1561 CXXRecordDecl *Record 1562 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1563 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1564 AllocArgs.size(), Record, /*AllowMissing=*/true, 1565 OperatorNew)) 1566 return true; 1567 } 1568 if (!OperatorNew) { 1569 // Didn't find a member overload. Look for a global one. 1570 DeclareGlobalNewDelete(); 1571 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1572 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1573 AllocArgs.size(), TUDecl, /*AllowMissing=*/false, 1574 OperatorNew)) 1575 return true; 1576 } 1577 1578 // We don't need an operator delete if we're running under 1579 // -fno-exceptions. 1580 if (!getLangOpts().Exceptions) { 1581 OperatorDelete = 0; 1582 return false; 1583 } 1584 1585 // FindAllocationOverload can change the passed in arguments, so we need to 1586 // copy them back. 1587 if (NumPlaceArgs > 0) 1588 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1589 1590 // C++ [expr.new]p19: 1591 // 1592 // If the new-expression begins with a unary :: operator, the 1593 // deallocation function's name is looked up in the global 1594 // scope. Otherwise, if the allocated type is a class type T or an 1595 // array thereof, the deallocation function's name is looked up in 1596 // the scope of T. If this lookup fails to find the name, or if 1597 // the allocated type is not a class type or array thereof, the 1598 // deallocation function's name is looked up in the global scope. 1599 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1600 if (AllocElemType->isRecordType() && !UseGlobal) { 1601 CXXRecordDecl *RD 1602 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1603 LookupQualifiedName(FoundDelete, RD); 1604 } 1605 if (FoundDelete.isAmbiguous()) 1606 return true; // FIXME: clean up expressions? 1607 1608 if (FoundDelete.empty()) { 1609 DeclareGlobalNewDelete(); 1610 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1611 } 1612 1613 FoundDelete.suppressDiagnostics(); 1614 1615 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1616 1617 // Whether we're looking for a placement operator delete is dictated 1618 // by whether we selected a placement operator new, not by whether 1619 // we had explicit placement arguments. This matters for things like 1620 // struct A { void *operator new(size_t, int = 0); ... }; 1621 // A *a = new A() 1622 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1623 1624 if (isPlacementNew) { 1625 // C++ [expr.new]p20: 1626 // A declaration of a placement deallocation function matches the 1627 // declaration of a placement allocation function if it has the 1628 // same number of parameters and, after parameter transformations 1629 // (8.3.5), all parameter types except the first are 1630 // identical. [...] 1631 // 1632 // To perform this comparison, we compute the function type that 1633 // the deallocation function should have, and use that type both 1634 // for template argument deduction and for comparison purposes. 1635 // 1636 // FIXME: this comparison should ignore CC and the like. 1637 QualType ExpectedFunctionType; 1638 { 1639 const FunctionProtoType *Proto 1640 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1641 1642 SmallVector<QualType, 4> ArgTypes; 1643 ArgTypes.push_back(Context.VoidPtrTy); 1644 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1645 ArgTypes.push_back(Proto->getArgType(I)); 1646 1647 FunctionProtoType::ExtProtoInfo EPI; 1648 EPI.Variadic = Proto->isVariadic(); 1649 1650 ExpectedFunctionType 1651 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI); 1652 } 1653 1654 for (LookupResult::iterator D = FoundDelete.begin(), 1655 DEnd = FoundDelete.end(); 1656 D != DEnd; ++D) { 1657 FunctionDecl *Fn = 0; 1658 if (FunctionTemplateDecl *FnTmpl 1659 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1660 // Perform template argument deduction to try to match the 1661 // expected function type. 1662 TemplateDeductionInfo Info(StartLoc); 1663 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1664 continue; 1665 } else 1666 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1667 1668 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1669 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1670 } 1671 } else { 1672 // C++ [expr.new]p20: 1673 // [...] Any non-placement deallocation function matches a 1674 // non-placement allocation function. [...] 1675 for (LookupResult::iterator D = FoundDelete.begin(), 1676 DEnd = FoundDelete.end(); 1677 D != DEnd; ++D) { 1678 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1679 if (isNonPlacementDeallocationFunction(Fn)) 1680 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1681 } 1682 } 1683 1684 // C++ [expr.new]p20: 1685 // [...] If the lookup finds a single matching deallocation 1686 // function, that function will be called; otherwise, no 1687 // deallocation function will be called. 1688 if (Matches.size() == 1) { 1689 OperatorDelete = Matches[0].second; 1690 1691 // C++0x [expr.new]p20: 1692 // If the lookup finds the two-parameter form of a usual 1693 // deallocation function (3.7.4.2) and that function, considered 1694 // as a placement deallocation function, would have been 1695 // selected as a match for the allocation function, the program 1696 // is ill-formed. 1697 if (NumPlaceArgs && getLangOpts().CPlusPlus11 && 1698 isNonPlacementDeallocationFunction(OperatorDelete)) { 1699 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1700 << SourceRange(PlaceArgs[0]->getLocStart(), 1701 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1702 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1703 << DeleteName; 1704 } else { 1705 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1706 Matches[0].first); 1707 } 1708 } 1709 1710 return false; 1711} 1712 1713/// FindAllocationOverload - Find an fitting overload for the allocation 1714/// function in the specified scope. 1715bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1716 DeclarationName Name, Expr** Args, 1717 unsigned NumArgs, DeclContext *Ctx, 1718 bool AllowMissing, FunctionDecl *&Operator, 1719 bool Diagnose) { 1720 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1721 LookupQualifiedName(R, Ctx); 1722 if (R.empty()) { 1723 if (AllowMissing || !Diagnose) 1724 return false; 1725 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1726 << Name << Range; 1727 } 1728 1729 if (R.isAmbiguous()) 1730 return true; 1731 1732 R.suppressDiagnostics(); 1733 1734 OverloadCandidateSet Candidates(StartLoc); 1735 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1736 Alloc != AllocEnd; ++Alloc) { 1737 // Even member operator new/delete are implicitly treated as 1738 // static, so don't use AddMemberCandidate. 1739 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1740 1741 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1742 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1743 /*ExplicitTemplateArgs=*/0, 1744 llvm::makeArrayRef(Args, NumArgs), 1745 Candidates, 1746 /*SuppressUserConversions=*/false); 1747 continue; 1748 } 1749 1750 FunctionDecl *Fn = cast<FunctionDecl>(D); 1751 AddOverloadCandidate(Fn, Alloc.getPair(), 1752 llvm::makeArrayRef(Args, NumArgs), Candidates, 1753 /*SuppressUserConversions=*/false); 1754 } 1755 1756 // Do the resolution. 1757 OverloadCandidateSet::iterator Best; 1758 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1759 case OR_Success: { 1760 // Got one! 1761 FunctionDecl *FnDecl = Best->Function; 1762 MarkFunctionReferenced(StartLoc, FnDecl); 1763 // The first argument is size_t, and the first parameter must be size_t, 1764 // too. This is checked on declaration and can be assumed. (It can't be 1765 // asserted on, though, since invalid decls are left in there.) 1766 // Watch out for variadic allocator function. 1767 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1768 for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) { 1769 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1770 FnDecl->getParamDecl(i)); 1771 1772 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1773 return true; 1774 1775 ExprResult Result 1776 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1777 if (Result.isInvalid()) 1778 return true; 1779 1780 Args[i] = Result.takeAs<Expr>(); 1781 } 1782 1783 Operator = FnDecl; 1784 1785 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), 1786 Best->FoundDecl, Diagnose) == AR_inaccessible) 1787 return true; 1788 1789 return false; 1790 } 1791 1792 case OR_No_Viable_Function: 1793 if (Diagnose) { 1794 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1795 << Name << Range; 1796 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1797 llvm::makeArrayRef(Args, NumArgs)); 1798 } 1799 return true; 1800 1801 case OR_Ambiguous: 1802 if (Diagnose) { 1803 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1804 << Name << Range; 1805 Candidates.NoteCandidates(*this, OCD_ViableCandidates, 1806 llvm::makeArrayRef(Args, NumArgs)); 1807 } 1808 return true; 1809 1810 case OR_Deleted: { 1811 if (Diagnose) { 1812 Diag(StartLoc, diag::err_ovl_deleted_call) 1813 << Best->Function->isDeleted() 1814 << Name 1815 << getDeletedOrUnavailableSuffix(Best->Function) 1816 << Range; 1817 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1818 llvm::makeArrayRef(Args, NumArgs)); 1819 } 1820 return true; 1821 } 1822 } 1823 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1824} 1825 1826 1827/// DeclareGlobalNewDelete - Declare the global forms of operator new and 1828/// delete. These are: 1829/// @code 1830/// // C++03: 1831/// void* operator new(std::size_t) throw(std::bad_alloc); 1832/// void* operator new[](std::size_t) throw(std::bad_alloc); 1833/// void operator delete(void *) throw(); 1834/// void operator delete[](void *) throw(); 1835/// // C++0x: 1836/// void* operator new(std::size_t); 1837/// void* operator new[](std::size_t); 1838/// void operator delete(void *); 1839/// void operator delete[](void *); 1840/// @endcode 1841/// C++0x operator delete is implicitly noexcept. 1842/// Note that the placement and nothrow forms of new are *not* implicitly 1843/// declared. Their use requires including \<new\>. 1844void Sema::DeclareGlobalNewDelete() { 1845 if (GlobalNewDeleteDeclared) 1846 return; 1847 1848 // C++ [basic.std.dynamic]p2: 1849 // [...] The following allocation and deallocation functions (18.4) are 1850 // implicitly declared in global scope in each translation unit of a 1851 // program 1852 // 1853 // C++03: 1854 // void* operator new(std::size_t) throw(std::bad_alloc); 1855 // void* operator new[](std::size_t) throw(std::bad_alloc); 1856 // void operator delete(void*) throw(); 1857 // void operator delete[](void*) throw(); 1858 // C++0x: 1859 // void* operator new(std::size_t); 1860 // void* operator new[](std::size_t); 1861 // void operator delete(void*); 1862 // void operator delete[](void*); 1863 // 1864 // These implicit declarations introduce only the function names operator 1865 // new, operator new[], operator delete, operator delete[]. 1866 // 1867 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1868 // "std" or "bad_alloc" as necessary to form the exception specification. 1869 // However, we do not make these implicit declarations visible to name 1870 // lookup. 1871 // Note that the C++0x versions of operator delete are deallocation functions, 1872 // and thus are implicitly noexcept. 1873 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) { 1874 // The "std::bad_alloc" class has not yet been declared, so build it 1875 // implicitly. 1876 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1877 getOrCreateStdNamespace(), 1878 SourceLocation(), SourceLocation(), 1879 &PP.getIdentifierTable().get("bad_alloc"), 1880 0); 1881 getStdBadAlloc()->setImplicit(true); 1882 } 1883 1884 GlobalNewDeleteDeclared = true; 1885 1886 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1887 QualType SizeT = Context.getSizeType(); 1888 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew; 1889 1890 DeclareGlobalAllocationFunction( 1891 Context.DeclarationNames.getCXXOperatorName(OO_New), 1892 VoidPtr, SizeT, AssumeSaneOperatorNew); 1893 DeclareGlobalAllocationFunction( 1894 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1895 VoidPtr, SizeT, AssumeSaneOperatorNew); 1896 DeclareGlobalAllocationFunction( 1897 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1898 Context.VoidTy, VoidPtr); 1899 DeclareGlobalAllocationFunction( 1900 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1901 Context.VoidTy, VoidPtr); 1902} 1903 1904/// DeclareGlobalAllocationFunction - Declares a single implicit global 1905/// allocation function if it doesn't already exist. 1906void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1907 QualType Return, QualType Argument, 1908 bool AddMallocAttr) { 1909 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1910 1911 // Check if this function is already declared. 1912 { 1913 DeclContext::lookup_result R = GlobalCtx->lookup(Name); 1914 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end(); 1915 Alloc != AllocEnd; ++Alloc) { 1916 // Only look at non-template functions, as it is the predefined, 1917 // non-templated allocation function we are trying to declare here. 1918 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1919 QualType InitialParamType = 1920 Context.getCanonicalType( 1921 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1922 // FIXME: Do we need to check for default arguments here? 1923 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1924 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1925 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1926 return; 1927 } 1928 } 1929 } 1930 } 1931 1932 QualType BadAllocType; 1933 bool HasBadAllocExceptionSpec 1934 = (Name.getCXXOverloadedOperator() == OO_New || 1935 Name.getCXXOverloadedOperator() == OO_Array_New); 1936 if (HasBadAllocExceptionSpec && !getLangOpts().CPlusPlus11) { 1937 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1938 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1939 } 1940 1941 FunctionProtoType::ExtProtoInfo EPI; 1942 if (HasBadAllocExceptionSpec) { 1943 if (!getLangOpts().CPlusPlus11) { 1944 EPI.ExceptionSpecType = EST_Dynamic; 1945 EPI.NumExceptions = 1; 1946 EPI.Exceptions = &BadAllocType; 1947 } 1948 } else { 1949 EPI.ExceptionSpecType = getLangOpts().CPlusPlus11 ? 1950 EST_BasicNoexcept : EST_DynamicNone; 1951 } 1952 1953 QualType FnType = Context.getFunctionType(Return, Argument, EPI); 1954 FunctionDecl *Alloc = 1955 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1956 SourceLocation(), Name, 1957 FnType, /*TInfo=*/0, SC_None, false, true); 1958 Alloc->setImplicit(); 1959 1960 if (AddMallocAttr) 1961 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1962 1963 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1964 SourceLocation(), 0, 1965 Argument, /*TInfo=*/0, 1966 SC_None, 0); 1967 Alloc->setParams(Param); 1968 1969 // FIXME: Also add this declaration to the IdentifierResolver, but 1970 // make sure it is at the end of the chain to coincide with the 1971 // global scope. 1972 Context.getTranslationUnitDecl()->addDecl(Alloc); 1973} 1974 1975bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1976 DeclarationName Name, 1977 FunctionDecl* &Operator, bool Diagnose) { 1978 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1979 // Try to find operator delete/operator delete[] in class scope. 1980 LookupQualifiedName(Found, RD); 1981 1982 if (Found.isAmbiguous()) 1983 return true; 1984 1985 Found.suppressDiagnostics(); 1986 1987 SmallVector<DeclAccessPair,4> Matches; 1988 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1989 F != FEnd; ++F) { 1990 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1991 1992 // Ignore template operator delete members from the check for a usual 1993 // deallocation function. 1994 if (isa<FunctionTemplateDecl>(ND)) 1995 continue; 1996 1997 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1998 Matches.push_back(F.getPair()); 1999 } 2000 2001 // There's exactly one suitable operator; pick it. 2002 if (Matches.size() == 1) { 2003 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 2004 2005 if (Operator->isDeleted()) { 2006 if (Diagnose) { 2007 Diag(StartLoc, diag::err_deleted_function_use); 2008 NoteDeletedFunction(Operator); 2009 } 2010 return true; 2011 } 2012 2013 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 2014 Matches[0], Diagnose) == AR_inaccessible) 2015 return true; 2016 2017 return false; 2018 2019 // We found multiple suitable operators; complain about the ambiguity. 2020 } else if (!Matches.empty()) { 2021 if (Diagnose) { 2022 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 2023 << Name << RD; 2024 2025 for (SmallVectorImpl<DeclAccessPair>::iterator 2026 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 2027 Diag((*F)->getUnderlyingDecl()->getLocation(), 2028 diag::note_member_declared_here) << Name; 2029 } 2030 return true; 2031 } 2032 2033 // We did find operator delete/operator delete[] declarations, but 2034 // none of them were suitable. 2035 if (!Found.empty()) { 2036 if (Diagnose) { 2037 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 2038 << Name << RD; 2039 2040 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 2041 F != FEnd; ++F) 2042 Diag((*F)->getUnderlyingDecl()->getLocation(), 2043 diag::note_member_declared_here) << Name; 2044 } 2045 return true; 2046 } 2047 2048 // Look for a global declaration. 2049 DeclareGlobalNewDelete(); 2050 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2051 2052 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 2053 Expr* DeallocArgs[1]; 2054 DeallocArgs[0] = &Null; 2055 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 2056 DeallocArgs, 1, TUDecl, !Diagnose, 2057 Operator, Diagnose)) 2058 return true; 2059 2060 assert(Operator && "Did not find a deallocation function!"); 2061 return false; 2062} 2063 2064/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 2065/// @code ::delete ptr; @endcode 2066/// or 2067/// @code delete [] ptr; @endcode 2068ExprResult 2069Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 2070 bool ArrayForm, Expr *ExE) { 2071 // C++ [expr.delete]p1: 2072 // The operand shall have a pointer type, or a class type having a single 2073 // conversion function to a pointer type. The result has type void. 2074 // 2075 // DR599 amends "pointer type" to "pointer to object type" in both cases. 2076 2077 ExprResult Ex = Owned(ExE); 2078 FunctionDecl *OperatorDelete = 0; 2079 bool ArrayFormAsWritten = ArrayForm; 2080 bool UsualArrayDeleteWantsSize = false; 2081 2082 if (!Ex.get()->isTypeDependent()) { 2083 // Perform lvalue-to-rvalue cast, if needed. 2084 Ex = DefaultLvalueConversion(Ex.take()); 2085 if (Ex.isInvalid()) 2086 return ExprError(); 2087 2088 QualType Type = Ex.get()->getType(); 2089 2090 if (const RecordType *Record = Type->getAs<RecordType>()) { 2091 if (RequireCompleteType(StartLoc, Type, 2092 diag::err_delete_incomplete_class_type)) 2093 return ExprError(); 2094 2095 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 2096 2097 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 2098 std::pair<CXXRecordDecl::conversion_iterator, 2099 CXXRecordDecl::conversion_iterator> 2100 Conversions = RD->getVisibleConversionFunctions(); 2101 for (CXXRecordDecl::conversion_iterator 2102 I = Conversions.first, E = Conversions.second; I != E; ++I) { 2103 NamedDecl *D = I.getDecl(); 2104 if (isa<UsingShadowDecl>(D)) 2105 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2106 2107 // Skip over templated conversion functions; they aren't considered. 2108 if (isa<FunctionTemplateDecl>(D)) 2109 continue; 2110 2111 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 2112 2113 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 2114 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 2115 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 2116 ObjectPtrConversions.push_back(Conv); 2117 } 2118 if (ObjectPtrConversions.size() == 1) { 2119 // We have a single conversion to a pointer-to-object type. Perform 2120 // that conversion. 2121 // TODO: don't redo the conversion calculation. 2122 ExprResult Res = 2123 PerformImplicitConversion(Ex.get(), 2124 ObjectPtrConversions.front()->getConversionType(), 2125 AA_Converting); 2126 if (Res.isUsable()) { 2127 Ex = Res; 2128 Type = Ex.get()->getType(); 2129 } 2130 } 2131 else if (ObjectPtrConversions.size() > 1) { 2132 Diag(StartLoc, diag::err_ambiguous_delete_operand) 2133 << Type << Ex.get()->getSourceRange(); 2134 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 2135 NoteOverloadCandidate(ObjectPtrConversions[i]); 2136 return ExprError(); 2137 } 2138 } 2139 2140 if (!Type->isPointerType()) 2141 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2142 << Type << Ex.get()->getSourceRange()); 2143 2144 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2145 QualType PointeeElem = Context.getBaseElementType(Pointee); 2146 2147 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2148 return Diag(Ex.get()->getLocStart(), 2149 diag::err_address_space_qualified_delete) 2150 << Pointee.getUnqualifiedType() << AddressSpace; 2151 2152 CXXRecordDecl *PointeeRD = 0; 2153 if (Pointee->isVoidType() && !isSFINAEContext()) { 2154 // The C++ standard bans deleting a pointer to a non-object type, which 2155 // effectively bans deletion of "void*". However, most compilers support 2156 // this, so we treat it as a warning unless we're in a SFINAE context. 2157 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2158 << Type << Ex.get()->getSourceRange(); 2159 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2160 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2161 << Type << Ex.get()->getSourceRange()); 2162 } else if (!Pointee->isDependentType()) { 2163 if (!RequireCompleteType(StartLoc, Pointee, 2164 diag::warn_delete_incomplete, Ex.get())) { 2165 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2166 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2167 } 2168 } 2169 2170 // C++ [expr.delete]p2: 2171 // [Note: a pointer to a const type can be the operand of a 2172 // delete-expression; it is not necessary to cast away the constness 2173 // (5.2.11) of the pointer expression before it is used as the operand 2174 // of the delete-expression. ] 2175 2176 if (Pointee->isArrayType() && !ArrayForm) { 2177 Diag(StartLoc, diag::warn_delete_array_type) 2178 << Type << Ex.get()->getSourceRange() 2179 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2180 ArrayForm = true; 2181 } 2182 2183 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2184 ArrayForm ? OO_Array_Delete : OO_Delete); 2185 2186 if (PointeeRD) { 2187 if (!UseGlobal && 2188 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2189 OperatorDelete)) 2190 return ExprError(); 2191 2192 // If we're allocating an array of records, check whether the 2193 // usual operator delete[] has a size_t parameter. 2194 if (ArrayForm) { 2195 // If the user specifically asked to use the global allocator, 2196 // we'll need to do the lookup into the class. 2197 if (UseGlobal) 2198 UsualArrayDeleteWantsSize = 2199 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2200 2201 // Otherwise, the usual operator delete[] should be the 2202 // function we just found. 2203 else if (isa<CXXMethodDecl>(OperatorDelete)) 2204 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2205 } 2206 2207 if (!PointeeRD->hasIrrelevantDestructor()) 2208 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2209 MarkFunctionReferenced(StartLoc, 2210 const_cast<CXXDestructorDecl*>(Dtor)); 2211 if (DiagnoseUseOfDecl(Dtor, StartLoc)) 2212 return ExprError(); 2213 } 2214 2215 // C++ [expr.delete]p3: 2216 // In the first alternative (delete object), if the static type of the 2217 // object to be deleted is different from its dynamic type, the static 2218 // type shall be a base class of the dynamic type of the object to be 2219 // deleted and the static type shall have a virtual destructor or the 2220 // behavior is undefined. 2221 // 2222 // Note: a final class cannot be derived from, no issue there 2223 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2224 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2225 if (dtor && !dtor->isVirtual()) { 2226 if (PointeeRD->isAbstract()) { 2227 // If the class is abstract, we warn by default, because we're 2228 // sure the code has undefined behavior. 2229 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2230 << PointeeElem; 2231 } else if (!ArrayForm) { 2232 // Otherwise, if this is not an array delete, it's a bit suspect, 2233 // but not necessarily wrong. 2234 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2235 } 2236 } 2237 } 2238 2239 } 2240 2241 if (!OperatorDelete) { 2242 // Look for a global declaration. 2243 DeclareGlobalNewDelete(); 2244 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2245 Expr *Arg = Ex.get(); 2246 if (!Context.hasSameType(Arg->getType(), Context.VoidPtrTy)) 2247 Arg = ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2248 CK_BitCast, Arg, 0, VK_RValue); 2249 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2250 &Arg, 1, TUDecl, /*AllowMissing=*/false, 2251 OperatorDelete)) 2252 return ExprError(); 2253 } 2254 2255 MarkFunctionReferenced(StartLoc, OperatorDelete); 2256 2257 // Check access and ambiguity of operator delete and destructor. 2258 if (PointeeRD) { 2259 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2260 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2261 PDiag(diag::err_access_dtor) << PointeeElem); 2262 } 2263 } 2264 2265 } 2266 2267 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2268 ArrayFormAsWritten, 2269 UsualArrayDeleteWantsSize, 2270 OperatorDelete, Ex.take(), StartLoc)); 2271} 2272 2273/// \brief Check the use of the given variable as a C++ condition in an if, 2274/// while, do-while, or switch statement. 2275ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2276 SourceLocation StmtLoc, 2277 bool ConvertToBoolean) { 2278 if (ConditionVar->isInvalidDecl()) 2279 return ExprError(); 2280 2281 QualType T = ConditionVar->getType(); 2282 2283 // C++ [stmt.select]p2: 2284 // The declarator shall not specify a function or an array. 2285 if (T->isFunctionType()) 2286 return ExprError(Diag(ConditionVar->getLocation(), 2287 diag::err_invalid_use_of_function_type) 2288 << ConditionVar->getSourceRange()); 2289 else if (T->isArrayType()) 2290 return ExprError(Diag(ConditionVar->getLocation(), 2291 diag::err_invalid_use_of_array_type) 2292 << ConditionVar->getSourceRange()); 2293 2294 ExprResult Condition = 2295 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2296 SourceLocation(), 2297 ConditionVar, 2298 /*enclosing*/ false, 2299 ConditionVar->getLocation(), 2300 ConditionVar->getType().getNonReferenceType(), 2301 VK_LValue)); 2302 2303 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2304 2305 if (ConvertToBoolean) { 2306 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2307 if (Condition.isInvalid()) 2308 return ExprError(); 2309 } 2310 2311 return Condition; 2312} 2313 2314/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2315ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2316 // C++ 6.4p4: 2317 // The value of a condition that is an initialized declaration in a statement 2318 // other than a switch statement is the value of the declared variable 2319 // implicitly converted to type bool. If that conversion is ill-formed, the 2320 // program is ill-formed. 2321 // The value of a condition that is an expression is the value of the 2322 // expression, implicitly converted to bool. 2323 // 2324 return PerformContextuallyConvertToBool(CondExpr); 2325} 2326 2327/// Helper function to determine whether this is the (deprecated) C++ 2328/// conversion from a string literal to a pointer to non-const char or 2329/// non-const wchar_t (for narrow and wide string literals, 2330/// respectively). 2331bool 2332Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2333 // Look inside the implicit cast, if it exists. 2334 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2335 From = Cast->getSubExpr(); 2336 2337 // A string literal (2.13.4) that is not a wide string literal can 2338 // be converted to an rvalue of type "pointer to char"; a wide 2339 // string literal can be converted to an rvalue of type "pointer 2340 // to wchar_t" (C++ 4.2p2). 2341 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2342 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2343 if (const BuiltinType *ToPointeeType 2344 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2345 // This conversion is considered only when there is an 2346 // explicit appropriate pointer target type (C++ 4.2p2). 2347 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2348 switch (StrLit->getKind()) { 2349 case StringLiteral::UTF8: 2350 case StringLiteral::UTF16: 2351 case StringLiteral::UTF32: 2352 // We don't allow UTF literals to be implicitly converted 2353 break; 2354 case StringLiteral::Ascii: 2355 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2356 ToPointeeType->getKind() == BuiltinType::Char_S); 2357 case StringLiteral::Wide: 2358 return ToPointeeType->isWideCharType(); 2359 } 2360 } 2361 } 2362 2363 return false; 2364} 2365 2366static ExprResult BuildCXXCastArgument(Sema &S, 2367 SourceLocation CastLoc, 2368 QualType Ty, 2369 CastKind Kind, 2370 CXXMethodDecl *Method, 2371 DeclAccessPair FoundDecl, 2372 bool HadMultipleCandidates, 2373 Expr *From) { 2374 switch (Kind) { 2375 default: llvm_unreachable("Unhandled cast kind!"); 2376 case CK_ConstructorConversion: { 2377 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2378 SmallVector<Expr*, 8> ConstructorArgs; 2379 2380 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs)) 2381 return ExprError(); 2382 2383 S.CheckConstructorAccess(CastLoc, Constructor, 2384 InitializedEntity::InitializeTemporary(Ty), 2385 Constructor->getAccess()); 2386 2387 ExprResult Result 2388 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2389 ConstructorArgs, HadMultipleCandidates, 2390 /*ListInit*/ false, /*ZeroInit*/ false, 2391 CXXConstructExpr::CK_Complete, SourceRange()); 2392 if (Result.isInvalid()) 2393 return ExprError(); 2394 2395 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2396 } 2397 2398 case CK_UserDefinedConversion: { 2399 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2400 2401 // Create an implicit call expr that calls it. 2402 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method); 2403 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv, 2404 HadMultipleCandidates); 2405 if (Result.isInvalid()) 2406 return ExprError(); 2407 // Record usage of conversion in an implicit cast. 2408 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2409 Result.get()->getType(), 2410 CK_UserDefinedConversion, 2411 Result.get(), 0, 2412 Result.get()->getValueKind())); 2413 2414 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2415 2416 return S.MaybeBindToTemporary(Result.get()); 2417 } 2418 } 2419} 2420 2421/// PerformImplicitConversion - Perform an implicit conversion of the 2422/// expression From to the type ToType using the pre-computed implicit 2423/// conversion sequence ICS. Returns the converted 2424/// expression. Action is the kind of conversion we're performing, 2425/// used in the error message. 2426ExprResult 2427Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2428 const ImplicitConversionSequence &ICS, 2429 AssignmentAction Action, 2430 CheckedConversionKind CCK) { 2431 switch (ICS.getKind()) { 2432 case ImplicitConversionSequence::StandardConversion: { 2433 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2434 Action, CCK); 2435 if (Res.isInvalid()) 2436 return ExprError(); 2437 From = Res.take(); 2438 break; 2439 } 2440 2441 case ImplicitConversionSequence::UserDefinedConversion: { 2442 2443 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2444 CastKind CastKind; 2445 QualType BeforeToType; 2446 assert(FD && "FIXME: aggregate initialization from init list"); 2447 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2448 CastKind = CK_UserDefinedConversion; 2449 2450 // If the user-defined conversion is specified by a conversion function, 2451 // the initial standard conversion sequence converts the source type to 2452 // the implicit object parameter of the conversion function. 2453 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2454 } else { 2455 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2456 CastKind = CK_ConstructorConversion; 2457 // Do no conversion if dealing with ... for the first conversion. 2458 if (!ICS.UserDefined.EllipsisConversion) { 2459 // If the user-defined conversion is specified by a constructor, the 2460 // initial standard conversion sequence converts the source type to the 2461 // type required by the argument of the constructor 2462 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2463 } 2464 } 2465 // Watch out for elipsis conversion. 2466 if (!ICS.UserDefined.EllipsisConversion) { 2467 ExprResult Res = 2468 PerformImplicitConversion(From, BeforeToType, 2469 ICS.UserDefined.Before, AA_Converting, 2470 CCK); 2471 if (Res.isInvalid()) 2472 return ExprError(); 2473 From = Res.take(); 2474 } 2475 2476 ExprResult CastArg 2477 = BuildCXXCastArgument(*this, 2478 From->getLocStart(), 2479 ToType.getNonReferenceType(), 2480 CastKind, cast<CXXMethodDecl>(FD), 2481 ICS.UserDefined.FoundConversionFunction, 2482 ICS.UserDefined.HadMultipleCandidates, 2483 From); 2484 2485 if (CastArg.isInvalid()) 2486 return ExprError(); 2487 2488 From = CastArg.take(); 2489 2490 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2491 AA_Converting, CCK); 2492 } 2493 2494 case ImplicitConversionSequence::AmbiguousConversion: 2495 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2496 PDiag(diag::err_typecheck_ambiguous_condition) 2497 << From->getSourceRange()); 2498 return ExprError(); 2499 2500 case ImplicitConversionSequence::EllipsisConversion: 2501 llvm_unreachable("Cannot perform an ellipsis conversion"); 2502 2503 case ImplicitConversionSequence::BadConversion: 2504 return ExprError(); 2505 } 2506 2507 // Everything went well. 2508 return Owned(From); 2509} 2510 2511/// PerformImplicitConversion - Perform an implicit conversion of the 2512/// expression From to the type ToType by following the standard 2513/// conversion sequence SCS. Returns the converted 2514/// expression. Flavor is the context in which we're performing this 2515/// conversion, for use in error messages. 2516ExprResult 2517Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2518 const StandardConversionSequence& SCS, 2519 AssignmentAction Action, 2520 CheckedConversionKind CCK) { 2521 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2522 2523 // Overall FIXME: we are recomputing too many types here and doing far too 2524 // much extra work. What this means is that we need to keep track of more 2525 // information that is computed when we try the implicit conversion initially, 2526 // so that we don't need to recompute anything here. 2527 QualType FromType = From->getType(); 2528 2529 if (SCS.CopyConstructor) { 2530 // FIXME: When can ToType be a reference type? 2531 assert(!ToType->isReferenceType()); 2532 if (SCS.Second == ICK_Derived_To_Base) { 2533 SmallVector<Expr*, 8> ConstructorArgs; 2534 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2535 From, /*FIXME:ConstructLoc*/SourceLocation(), 2536 ConstructorArgs)) 2537 return ExprError(); 2538 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2539 ToType, SCS.CopyConstructor, 2540 ConstructorArgs, 2541 /*HadMultipleCandidates*/ false, 2542 /*ListInit*/ false, /*ZeroInit*/ false, 2543 CXXConstructExpr::CK_Complete, 2544 SourceRange()); 2545 } 2546 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2547 ToType, SCS.CopyConstructor, 2548 From, /*HadMultipleCandidates*/ false, 2549 /*ListInit*/ false, /*ZeroInit*/ false, 2550 CXXConstructExpr::CK_Complete, 2551 SourceRange()); 2552 } 2553 2554 // Resolve overloaded function references. 2555 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2556 DeclAccessPair Found; 2557 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2558 true, Found); 2559 if (!Fn) 2560 return ExprError(); 2561 2562 if (DiagnoseUseOfDecl(Fn, From->getLocStart())) 2563 return ExprError(); 2564 2565 From = FixOverloadedFunctionReference(From, Found, Fn); 2566 FromType = From->getType(); 2567 } 2568 2569 // Perform the first implicit conversion. 2570 switch (SCS.First) { 2571 case ICK_Identity: 2572 // Nothing to do. 2573 break; 2574 2575 case ICK_Lvalue_To_Rvalue: { 2576 assert(From->getObjectKind() != OK_ObjCProperty); 2577 FromType = FromType.getUnqualifiedType(); 2578 ExprResult FromRes = DefaultLvalueConversion(From); 2579 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2580 From = FromRes.take(); 2581 break; 2582 } 2583 2584 case ICK_Array_To_Pointer: 2585 FromType = Context.getArrayDecayedType(FromType); 2586 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2587 VK_RValue, /*BasePath=*/0, CCK).take(); 2588 break; 2589 2590 case ICK_Function_To_Pointer: 2591 FromType = Context.getPointerType(FromType); 2592 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2593 VK_RValue, /*BasePath=*/0, CCK).take(); 2594 break; 2595 2596 default: 2597 llvm_unreachable("Improper first standard conversion"); 2598 } 2599 2600 // Perform the second implicit conversion 2601 switch (SCS.Second) { 2602 case ICK_Identity: 2603 // If both sides are functions (or pointers/references to them), there could 2604 // be incompatible exception declarations. 2605 if (CheckExceptionSpecCompatibility(From, ToType)) 2606 return ExprError(); 2607 // Nothing else to do. 2608 break; 2609 2610 case ICK_NoReturn_Adjustment: 2611 // If both sides are functions (or pointers/references to them), there could 2612 // be incompatible exception declarations. 2613 if (CheckExceptionSpecCompatibility(From, ToType)) 2614 return ExprError(); 2615 2616 From = ImpCastExprToType(From, ToType, CK_NoOp, 2617 VK_RValue, /*BasePath=*/0, CCK).take(); 2618 break; 2619 2620 case ICK_Integral_Promotion: 2621 case ICK_Integral_Conversion: 2622 if (ToType->isBooleanType()) { 2623 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() && 2624 SCS.Second == ICK_Integral_Promotion && 2625 "only enums with fixed underlying type can promote to bool"); 2626 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean, 2627 VK_RValue, /*BasePath=*/0, CCK).take(); 2628 } else { 2629 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2630 VK_RValue, /*BasePath=*/0, CCK).take(); 2631 } 2632 break; 2633 2634 case ICK_Floating_Promotion: 2635 case ICK_Floating_Conversion: 2636 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2637 VK_RValue, /*BasePath=*/0, CCK).take(); 2638 break; 2639 2640 case ICK_Complex_Promotion: 2641 case ICK_Complex_Conversion: { 2642 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2643 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2644 CastKind CK; 2645 if (FromEl->isRealFloatingType()) { 2646 if (ToEl->isRealFloatingType()) 2647 CK = CK_FloatingComplexCast; 2648 else 2649 CK = CK_FloatingComplexToIntegralComplex; 2650 } else if (ToEl->isRealFloatingType()) { 2651 CK = CK_IntegralComplexToFloatingComplex; 2652 } else { 2653 CK = CK_IntegralComplexCast; 2654 } 2655 From = ImpCastExprToType(From, ToType, CK, 2656 VK_RValue, /*BasePath=*/0, CCK).take(); 2657 break; 2658 } 2659 2660 case ICK_Floating_Integral: 2661 if (ToType->isRealFloatingType()) 2662 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2663 VK_RValue, /*BasePath=*/0, CCK).take(); 2664 else 2665 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2666 VK_RValue, /*BasePath=*/0, CCK).take(); 2667 break; 2668 2669 case ICK_Compatible_Conversion: 2670 From = ImpCastExprToType(From, ToType, CK_NoOp, 2671 VK_RValue, /*BasePath=*/0, CCK).take(); 2672 break; 2673 2674 case ICK_Writeback_Conversion: 2675 case ICK_Pointer_Conversion: { 2676 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2677 // Diagnose incompatible Objective-C conversions 2678 if (Action == AA_Initializing || Action == AA_Assigning) 2679 Diag(From->getLocStart(), 2680 diag::ext_typecheck_convert_incompatible_pointer) 2681 << ToType << From->getType() << Action 2682 << From->getSourceRange() << 0; 2683 else 2684 Diag(From->getLocStart(), 2685 diag::ext_typecheck_convert_incompatible_pointer) 2686 << From->getType() << ToType << Action 2687 << From->getSourceRange() << 0; 2688 2689 if (From->getType()->isObjCObjectPointerType() && 2690 ToType->isObjCObjectPointerType()) 2691 EmitRelatedResultTypeNote(From); 2692 } 2693 else if (getLangOpts().ObjCAutoRefCount && 2694 !CheckObjCARCUnavailableWeakConversion(ToType, 2695 From->getType())) { 2696 if (Action == AA_Initializing) 2697 Diag(From->getLocStart(), 2698 diag::err_arc_weak_unavailable_assign); 2699 else 2700 Diag(From->getLocStart(), 2701 diag::err_arc_convesion_of_weak_unavailable) 2702 << (Action == AA_Casting) << From->getType() << ToType 2703 << From->getSourceRange(); 2704 } 2705 2706 CastKind Kind = CK_Invalid; 2707 CXXCastPath BasePath; 2708 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2709 return ExprError(); 2710 2711 // Make sure we extend blocks if necessary. 2712 // FIXME: doing this here is really ugly. 2713 if (Kind == CK_BlockPointerToObjCPointerCast) { 2714 ExprResult E = From; 2715 (void) PrepareCastToObjCObjectPointer(E); 2716 From = E.take(); 2717 } 2718 2719 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2720 .take(); 2721 break; 2722 } 2723 2724 case ICK_Pointer_Member: { 2725 CastKind Kind = CK_Invalid; 2726 CXXCastPath BasePath; 2727 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2728 return ExprError(); 2729 if (CheckExceptionSpecCompatibility(From, ToType)) 2730 return ExprError(); 2731 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2732 .take(); 2733 break; 2734 } 2735 2736 case ICK_Boolean_Conversion: 2737 // Perform half-to-boolean conversion via float. 2738 if (From->getType()->isHalfType()) { 2739 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2740 FromType = Context.FloatTy; 2741 } 2742 2743 From = ImpCastExprToType(From, Context.BoolTy, 2744 ScalarTypeToBooleanCastKind(FromType), 2745 VK_RValue, /*BasePath=*/0, CCK).take(); 2746 break; 2747 2748 case ICK_Derived_To_Base: { 2749 CXXCastPath BasePath; 2750 if (CheckDerivedToBaseConversion(From->getType(), 2751 ToType.getNonReferenceType(), 2752 From->getLocStart(), 2753 From->getSourceRange(), 2754 &BasePath, 2755 CStyle)) 2756 return ExprError(); 2757 2758 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2759 CK_DerivedToBase, From->getValueKind(), 2760 &BasePath, CCK).take(); 2761 break; 2762 } 2763 2764 case ICK_Vector_Conversion: 2765 From = ImpCastExprToType(From, ToType, CK_BitCast, 2766 VK_RValue, /*BasePath=*/0, CCK).take(); 2767 break; 2768 2769 case ICK_Vector_Splat: 2770 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2771 VK_RValue, /*BasePath=*/0, CCK).take(); 2772 break; 2773 2774 case ICK_Complex_Real: 2775 // Case 1. x -> _Complex y 2776 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2777 QualType ElType = ToComplex->getElementType(); 2778 bool isFloatingComplex = ElType->isRealFloatingType(); 2779 2780 // x -> y 2781 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2782 // do nothing 2783 } else if (From->getType()->isRealFloatingType()) { 2784 From = ImpCastExprToType(From, ElType, 2785 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2786 } else { 2787 assert(From->getType()->isIntegerType()); 2788 From = ImpCastExprToType(From, ElType, 2789 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2790 } 2791 // y -> _Complex y 2792 From = ImpCastExprToType(From, ToType, 2793 isFloatingComplex ? CK_FloatingRealToComplex 2794 : CK_IntegralRealToComplex).take(); 2795 2796 // Case 2. _Complex x -> y 2797 } else { 2798 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2799 assert(FromComplex); 2800 2801 QualType ElType = FromComplex->getElementType(); 2802 bool isFloatingComplex = ElType->isRealFloatingType(); 2803 2804 // _Complex x -> x 2805 From = ImpCastExprToType(From, ElType, 2806 isFloatingComplex ? CK_FloatingComplexToReal 2807 : CK_IntegralComplexToReal, 2808 VK_RValue, /*BasePath=*/0, CCK).take(); 2809 2810 // x -> y 2811 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2812 // do nothing 2813 } else if (ToType->isRealFloatingType()) { 2814 From = ImpCastExprToType(From, ToType, 2815 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2816 VK_RValue, /*BasePath=*/0, CCK).take(); 2817 } else { 2818 assert(ToType->isIntegerType()); 2819 From = ImpCastExprToType(From, ToType, 2820 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2821 VK_RValue, /*BasePath=*/0, CCK).take(); 2822 } 2823 } 2824 break; 2825 2826 case ICK_Block_Pointer_Conversion: { 2827 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2828 VK_RValue, /*BasePath=*/0, CCK).take(); 2829 break; 2830 } 2831 2832 case ICK_TransparentUnionConversion: { 2833 ExprResult FromRes = Owned(From); 2834 Sema::AssignConvertType ConvTy = 2835 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2836 if (FromRes.isInvalid()) 2837 return ExprError(); 2838 From = FromRes.take(); 2839 assert ((ConvTy == Sema::Compatible) && 2840 "Improper transparent union conversion"); 2841 (void)ConvTy; 2842 break; 2843 } 2844 2845 case ICK_Zero_Event_Conversion: 2846 From = ImpCastExprToType(From, ToType, 2847 CK_ZeroToOCLEvent, 2848 From->getValueKind()).take(); 2849 break; 2850 2851 case ICK_Lvalue_To_Rvalue: 2852 case ICK_Array_To_Pointer: 2853 case ICK_Function_To_Pointer: 2854 case ICK_Qualification: 2855 case ICK_Num_Conversion_Kinds: 2856 llvm_unreachable("Improper second standard conversion"); 2857 } 2858 2859 switch (SCS.Third) { 2860 case ICK_Identity: 2861 // Nothing to do. 2862 break; 2863 2864 case ICK_Qualification: { 2865 // The qualification keeps the category of the inner expression, unless the 2866 // target type isn't a reference. 2867 ExprValueKind VK = ToType->isReferenceType() ? 2868 From->getValueKind() : VK_RValue; 2869 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2870 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2871 2872 if (SCS.DeprecatedStringLiteralToCharPtr && 2873 !getLangOpts().WritableStrings) 2874 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2875 << ToType.getNonReferenceType(); 2876 2877 break; 2878 } 2879 2880 default: 2881 llvm_unreachable("Improper third standard conversion"); 2882 } 2883 2884 // If this conversion sequence involved a scalar -> atomic conversion, perform 2885 // that conversion now. 2886 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) 2887 if (Context.hasSameType(ToAtomic->getValueType(), From->getType())) 2888 From = ImpCastExprToType(From, ToType, CK_NonAtomicToAtomic, VK_RValue, 0, 2889 CCK).take(); 2890 2891 return Owned(From); 2892} 2893 2894ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2895 SourceLocation KWLoc, 2896 ParsedType Ty, 2897 SourceLocation RParen) { 2898 TypeSourceInfo *TSInfo; 2899 QualType T = GetTypeFromParser(Ty, &TSInfo); 2900 2901 if (!TSInfo) 2902 TSInfo = Context.getTrivialTypeSourceInfo(T); 2903 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2904} 2905 2906/// \brief Check the completeness of a type in a unary type trait. 2907/// 2908/// If the particular type trait requires a complete type, tries to complete 2909/// it. If completing the type fails, a diagnostic is emitted and false 2910/// returned. If completing the type succeeds or no completion was required, 2911/// returns true. 2912static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2913 UnaryTypeTrait UTT, 2914 SourceLocation Loc, 2915 QualType ArgTy) { 2916 // C++0x [meta.unary.prop]p3: 2917 // For all of the class templates X declared in this Clause, instantiating 2918 // that template with a template argument that is a class template 2919 // specialization may result in the implicit instantiation of the template 2920 // argument if and only if the semantics of X require that the argument 2921 // must be a complete type. 2922 // We apply this rule to all the type trait expressions used to implement 2923 // these class templates. We also try to follow any GCC documented behavior 2924 // in these expressions to ensure portability of standard libraries. 2925 switch (UTT) { 2926 // is_complete_type somewhat obviously cannot require a complete type. 2927 case UTT_IsCompleteType: 2928 // Fall-through 2929 2930 // These traits are modeled on the type predicates in C++0x 2931 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2932 // requiring a complete type, as whether or not they return true cannot be 2933 // impacted by the completeness of the type. 2934 case UTT_IsVoid: 2935 case UTT_IsIntegral: 2936 case UTT_IsFloatingPoint: 2937 case UTT_IsArray: 2938 case UTT_IsPointer: 2939 case UTT_IsLvalueReference: 2940 case UTT_IsRvalueReference: 2941 case UTT_IsMemberFunctionPointer: 2942 case UTT_IsMemberObjectPointer: 2943 case UTT_IsEnum: 2944 case UTT_IsUnion: 2945 case UTT_IsClass: 2946 case UTT_IsFunction: 2947 case UTT_IsReference: 2948 case UTT_IsArithmetic: 2949 case UTT_IsFundamental: 2950 case UTT_IsObject: 2951 case UTT_IsScalar: 2952 case UTT_IsCompound: 2953 case UTT_IsMemberPointer: 2954 // Fall-through 2955 2956 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2957 // which requires some of its traits to have the complete type. However, 2958 // the completeness of the type cannot impact these traits' semantics, and 2959 // so they don't require it. This matches the comments on these traits in 2960 // Table 49. 2961 case UTT_IsConst: 2962 case UTT_IsVolatile: 2963 case UTT_IsSigned: 2964 case UTT_IsUnsigned: 2965 return true; 2966 2967 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2968 // applied to a complete type. 2969 case UTT_IsTrivial: 2970 case UTT_IsTriviallyCopyable: 2971 case UTT_IsStandardLayout: 2972 case UTT_IsPOD: 2973 case UTT_IsLiteral: 2974 case UTT_IsEmpty: 2975 case UTT_IsPolymorphic: 2976 case UTT_IsAbstract: 2977 case UTT_IsInterfaceClass: 2978 // Fall-through 2979 2980 // These traits require a complete type. 2981 case UTT_IsFinal: 2982 2983 // These trait expressions are designed to help implement predicates in 2984 // [meta.unary.prop] despite not being named the same. They are specified 2985 // by both GCC and the Embarcadero C++ compiler, and require the complete 2986 // type due to the overarching C++0x type predicates being implemented 2987 // requiring the complete type. 2988 case UTT_HasNothrowAssign: 2989 case UTT_HasNothrowMoveAssign: 2990 case UTT_HasNothrowConstructor: 2991 case UTT_HasNothrowCopy: 2992 case UTT_HasTrivialAssign: 2993 case UTT_HasTrivialMoveAssign: 2994 case UTT_HasTrivialDefaultConstructor: 2995 case UTT_HasTrivialMoveConstructor: 2996 case UTT_HasTrivialCopy: 2997 case UTT_HasTrivialDestructor: 2998 case UTT_HasVirtualDestructor: 2999 // Arrays of unknown bound are expressly allowed. 3000 QualType ElTy = ArgTy; 3001 if (ArgTy->isIncompleteArrayType()) 3002 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 3003 3004 // The void type is expressly allowed. 3005 if (ElTy->isVoidType()) 3006 return true; 3007 3008 return !S.RequireCompleteType( 3009 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 3010 } 3011 llvm_unreachable("Type trait not handled by switch"); 3012} 3013 3014static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op, 3015 Sema &Self, SourceLocation KeyLoc, ASTContext &C, 3016 bool (CXXRecordDecl::*HasTrivial)() const, 3017 bool (CXXRecordDecl::*HasNonTrivial)() const, 3018 bool (CXXMethodDecl::*IsDesiredOp)() const) 3019{ 3020 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3021 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)()) 3022 return true; 3023 3024 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op); 3025 DeclarationNameInfo NameInfo(Name, KeyLoc); 3026 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName); 3027 if (Self.LookupQualifiedName(Res, RD)) { 3028 bool FoundOperator = false; 3029 Res.suppressDiagnostics(); 3030 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3031 Op != OpEnd; ++Op) { 3032 if (isa<FunctionTemplateDecl>(*Op)) 3033 continue; 3034 3035 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3036 if((Operator->*IsDesiredOp)()) { 3037 FoundOperator = true; 3038 const FunctionProtoType *CPT = 3039 Operator->getType()->getAs<FunctionProtoType>(); 3040 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3041 if (!CPT || !CPT->isNothrow(Self.Context)) 3042 return false; 3043 } 3044 } 3045 return FoundOperator; 3046 } 3047 return false; 3048} 3049 3050static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 3051 SourceLocation KeyLoc, QualType T) { 3052 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3053 3054 ASTContext &C = Self.Context; 3055 switch(UTT) { 3056 // Type trait expressions corresponding to the primary type category 3057 // predicates in C++0x [meta.unary.cat]. 3058 case UTT_IsVoid: 3059 return T->isVoidType(); 3060 case UTT_IsIntegral: 3061 return T->isIntegralType(C); 3062 case UTT_IsFloatingPoint: 3063 return T->isFloatingType(); 3064 case UTT_IsArray: 3065 return T->isArrayType(); 3066 case UTT_IsPointer: 3067 return T->isPointerType(); 3068 case UTT_IsLvalueReference: 3069 return T->isLValueReferenceType(); 3070 case UTT_IsRvalueReference: 3071 return T->isRValueReferenceType(); 3072 case UTT_IsMemberFunctionPointer: 3073 return T->isMemberFunctionPointerType(); 3074 case UTT_IsMemberObjectPointer: 3075 return T->isMemberDataPointerType(); 3076 case UTT_IsEnum: 3077 return T->isEnumeralType(); 3078 case UTT_IsUnion: 3079 return T->isUnionType(); 3080 case UTT_IsClass: 3081 return T->isClassType() || T->isStructureType() || T->isInterfaceType(); 3082 case UTT_IsFunction: 3083 return T->isFunctionType(); 3084 3085 // Type trait expressions which correspond to the convenient composition 3086 // predicates in C++0x [meta.unary.comp]. 3087 case UTT_IsReference: 3088 return T->isReferenceType(); 3089 case UTT_IsArithmetic: 3090 return T->isArithmeticType() && !T->isEnumeralType(); 3091 case UTT_IsFundamental: 3092 return T->isFundamentalType(); 3093 case UTT_IsObject: 3094 return T->isObjectType(); 3095 case UTT_IsScalar: 3096 // Note: semantic analysis depends on Objective-C lifetime types to be 3097 // considered scalar types. However, such types do not actually behave 3098 // like scalar types at run time (since they may require retain/release 3099 // operations), so we report them as non-scalar. 3100 if (T->isObjCLifetimeType()) { 3101 switch (T.getObjCLifetime()) { 3102 case Qualifiers::OCL_None: 3103 case Qualifiers::OCL_ExplicitNone: 3104 return true; 3105 3106 case Qualifiers::OCL_Strong: 3107 case Qualifiers::OCL_Weak: 3108 case Qualifiers::OCL_Autoreleasing: 3109 return false; 3110 } 3111 } 3112 3113 return T->isScalarType(); 3114 case UTT_IsCompound: 3115 return T->isCompoundType(); 3116 case UTT_IsMemberPointer: 3117 return T->isMemberPointerType(); 3118 3119 // Type trait expressions which correspond to the type property predicates 3120 // in C++0x [meta.unary.prop]. 3121 case UTT_IsConst: 3122 return T.isConstQualified(); 3123 case UTT_IsVolatile: 3124 return T.isVolatileQualified(); 3125 case UTT_IsTrivial: 3126 return T.isTrivialType(Self.Context); 3127 case UTT_IsTriviallyCopyable: 3128 return T.isTriviallyCopyableType(Self.Context); 3129 case UTT_IsStandardLayout: 3130 return T->isStandardLayoutType(); 3131 case UTT_IsPOD: 3132 return T.isPODType(Self.Context); 3133 case UTT_IsLiteral: 3134 return T->isLiteralType(Self.Context); 3135 case UTT_IsEmpty: 3136 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3137 return !RD->isUnion() && RD->isEmpty(); 3138 return false; 3139 case UTT_IsPolymorphic: 3140 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3141 return RD->isPolymorphic(); 3142 return false; 3143 case UTT_IsAbstract: 3144 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3145 return RD->isAbstract(); 3146 return false; 3147 case UTT_IsInterfaceClass: 3148 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3149 return RD->isInterface(); 3150 return false; 3151 case UTT_IsFinal: 3152 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3153 return RD->hasAttr<FinalAttr>(); 3154 return false; 3155 case UTT_IsSigned: 3156 return T->isSignedIntegerType(); 3157 case UTT_IsUnsigned: 3158 return T->isUnsignedIntegerType(); 3159 3160 // Type trait expressions which query classes regarding their construction, 3161 // destruction, and copying. Rather than being based directly on the 3162 // related type predicates in the standard, they are specified by both 3163 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 3164 // specifications. 3165 // 3166 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 3167 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3168 // 3169 // Note that these builtins do not behave as documented in g++: if a class 3170 // has both a trivial and a non-trivial special member of a particular kind, 3171 // they return false! For now, we emulate this behavior. 3172 // FIXME: This appears to be a g++ bug: more complex cases reveal that it 3173 // does not correctly compute triviality in the presence of multiple special 3174 // members of the same kind. Revisit this once the g++ bug is fixed. 3175 case UTT_HasTrivialDefaultConstructor: 3176 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3177 // If __is_pod (type) is true then the trait is true, else if type is 3178 // a cv class or union type (or array thereof) with a trivial default 3179 // constructor ([class.ctor]) then the trait is true, else it is false. 3180 if (T.isPODType(Self.Context)) 3181 return true; 3182 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3183 return RD->hasTrivialDefaultConstructor() && 3184 !RD->hasNonTrivialDefaultConstructor(); 3185 return false; 3186 case UTT_HasTrivialMoveConstructor: 3187 // This trait is implemented by MSVC 2012 and needed to parse the 3188 // standard library headers. Specifically this is used as the logic 3189 // behind std::is_trivially_move_constructible (20.9.4.3). 3190 if (T.isPODType(Self.Context)) 3191 return true; 3192 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3193 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor(); 3194 return false; 3195 case UTT_HasTrivialCopy: 3196 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3197 // If __is_pod (type) is true or type is a reference type then 3198 // the trait is true, else if type is a cv class or union type 3199 // with a trivial copy constructor ([class.copy]) then the trait 3200 // is true, else it is false. 3201 if (T.isPODType(Self.Context) || T->isReferenceType()) 3202 return true; 3203 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3204 return RD->hasTrivialCopyConstructor() && 3205 !RD->hasNonTrivialCopyConstructor(); 3206 return false; 3207 case UTT_HasTrivialMoveAssign: 3208 // This trait is implemented by MSVC 2012 and needed to parse the 3209 // standard library headers. Specifically it is used as the logic 3210 // behind std::is_trivially_move_assignable (20.9.4.3) 3211 if (T.isPODType(Self.Context)) 3212 return true; 3213 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3214 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment(); 3215 return false; 3216 case UTT_HasTrivialAssign: 3217 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3218 // If type is const qualified or is a reference type then the 3219 // trait is false. Otherwise if __is_pod (type) is true then the 3220 // trait is true, else if type is a cv class or union type with 3221 // a trivial copy assignment ([class.copy]) then the trait is 3222 // true, else it is false. 3223 // Note: the const and reference restrictions are interesting, 3224 // given that const and reference members don't prevent a class 3225 // from having a trivial copy assignment operator (but do cause 3226 // errors if the copy assignment operator is actually used, q.v. 3227 // [class.copy]p12). 3228 3229 if (T.isConstQualified()) 3230 return false; 3231 if (T.isPODType(Self.Context)) 3232 return true; 3233 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3234 return RD->hasTrivialCopyAssignment() && 3235 !RD->hasNonTrivialCopyAssignment(); 3236 return false; 3237 case UTT_HasTrivialDestructor: 3238 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3239 // If __is_pod (type) is true or type is a reference type 3240 // then the trait is true, else if type is a cv class or union 3241 // type (or array thereof) with a trivial destructor 3242 // ([class.dtor]) then the trait is true, else it is 3243 // false. 3244 if (T.isPODType(Self.Context) || T->isReferenceType()) 3245 return true; 3246 3247 // Objective-C++ ARC: autorelease types don't require destruction. 3248 if (T->isObjCLifetimeType() && 3249 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3250 return true; 3251 3252 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3253 return RD->hasTrivialDestructor(); 3254 return false; 3255 // TODO: Propagate nothrowness for implicitly declared special members. 3256 case UTT_HasNothrowAssign: 3257 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3258 // If type is const qualified or is a reference type then the 3259 // trait is false. Otherwise if __has_trivial_assign (type) 3260 // is true then the trait is true, else if type is a cv class 3261 // or union type with copy assignment operators that are known 3262 // not to throw an exception then the trait is true, else it is 3263 // false. 3264 if (C.getBaseElementType(T).isConstQualified()) 3265 return false; 3266 if (T->isReferenceType()) 3267 return false; 3268 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3269 return true; 3270 3271 if (const RecordType *RT = T->getAs<RecordType>()) 3272 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C, 3273 &CXXRecordDecl::hasTrivialCopyAssignment, 3274 &CXXRecordDecl::hasNonTrivialCopyAssignment, 3275 &CXXMethodDecl::isCopyAssignmentOperator); 3276 return false; 3277 case UTT_HasNothrowMoveAssign: 3278 // This trait is implemented by MSVC 2012 and needed to parse the 3279 // standard library headers. Specifically this is used as the logic 3280 // behind std::is_nothrow_move_assignable (20.9.4.3). 3281 if (T.isPODType(Self.Context)) 3282 return true; 3283 3284 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) 3285 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C, 3286 &CXXRecordDecl::hasTrivialMoveAssignment, 3287 &CXXRecordDecl::hasNonTrivialMoveAssignment, 3288 &CXXMethodDecl::isMoveAssignmentOperator); 3289 return false; 3290 case UTT_HasNothrowCopy: 3291 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3292 // If __has_trivial_copy (type) is true then the trait is true, else 3293 // if type is a cv class or union type with copy constructors that are 3294 // known not to throw an exception then the trait is true, else it is 3295 // false. 3296 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3297 return true; 3298 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) { 3299 if (RD->hasTrivialCopyConstructor() && 3300 !RD->hasNonTrivialCopyConstructor()) 3301 return true; 3302 3303 bool FoundConstructor = false; 3304 unsigned FoundTQs; 3305 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3306 for (DeclContext::lookup_const_iterator Con = R.begin(), 3307 ConEnd = R.end(); Con != ConEnd; ++Con) { 3308 // A template constructor is never a copy constructor. 3309 // FIXME: However, it may actually be selected at the actual overload 3310 // resolution point. 3311 if (isa<FunctionTemplateDecl>(*Con)) 3312 continue; 3313 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3314 if (Constructor->isCopyConstructor(FoundTQs)) { 3315 FoundConstructor = true; 3316 const FunctionProtoType *CPT 3317 = Constructor->getType()->getAs<FunctionProtoType>(); 3318 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3319 if (!CPT) 3320 return false; 3321 // FIXME: check whether evaluating default arguments can throw. 3322 // For now, we'll be conservative and assume that they can throw. 3323 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3324 return false; 3325 } 3326 } 3327 3328 return FoundConstructor; 3329 } 3330 return false; 3331 case UTT_HasNothrowConstructor: 3332 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3333 // If __has_trivial_constructor (type) is true then the trait is 3334 // true, else if type is a cv class or union type (or array 3335 // thereof) with a default constructor that is known not to 3336 // throw an exception then the trait is true, else it is false. 3337 if (T.isPODType(C) || T->isObjCLifetimeType()) 3338 return true; 3339 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) { 3340 if (RD->hasTrivialDefaultConstructor() && 3341 !RD->hasNonTrivialDefaultConstructor()) 3342 return true; 3343 3344 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3345 for (DeclContext::lookup_const_iterator Con = R.begin(), 3346 ConEnd = R.end(); Con != ConEnd; ++Con) { 3347 // FIXME: In C++0x, a constructor template can be a default constructor. 3348 if (isa<FunctionTemplateDecl>(*Con)) 3349 continue; 3350 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3351 if (Constructor->isDefaultConstructor()) { 3352 const FunctionProtoType *CPT 3353 = Constructor->getType()->getAs<FunctionProtoType>(); 3354 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3355 if (!CPT) 3356 return false; 3357 // TODO: check whether evaluating default arguments can throw. 3358 // For now, we'll be conservative and assume that they can throw. 3359 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3360 } 3361 } 3362 } 3363 return false; 3364 case UTT_HasVirtualDestructor: 3365 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3366 // If type is a class type with a virtual destructor ([class.dtor]) 3367 // then the trait is true, else it is false. 3368 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3369 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3370 return Destructor->isVirtual(); 3371 return false; 3372 3373 // These type trait expressions are modeled on the specifications for the 3374 // Embarcadero C++0x type trait functions: 3375 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3376 case UTT_IsCompleteType: 3377 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3378 // Returns True if and only if T is a complete type at the point of the 3379 // function call. 3380 return !T->isIncompleteType(); 3381 } 3382 llvm_unreachable("Type trait not covered by switch"); 3383} 3384 3385ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3386 SourceLocation KWLoc, 3387 TypeSourceInfo *TSInfo, 3388 SourceLocation RParen) { 3389 QualType T = TSInfo->getType(); 3390 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3391 return ExprError(); 3392 3393 bool Value = false; 3394 if (!T->isDependentType()) 3395 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3396 3397 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3398 RParen, Context.BoolTy)); 3399} 3400 3401ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3402 SourceLocation KWLoc, 3403 ParsedType LhsTy, 3404 ParsedType RhsTy, 3405 SourceLocation RParen) { 3406 TypeSourceInfo *LhsTSInfo; 3407 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3408 if (!LhsTSInfo) 3409 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3410 3411 TypeSourceInfo *RhsTSInfo; 3412 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3413 if (!RhsTSInfo) 3414 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3415 3416 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3417} 3418 3419/// \brief Determine whether T has a non-trivial Objective-C lifetime in 3420/// ARC mode. 3421static bool hasNontrivialObjCLifetime(QualType T) { 3422 switch (T.getObjCLifetime()) { 3423 case Qualifiers::OCL_ExplicitNone: 3424 return false; 3425 3426 case Qualifiers::OCL_Strong: 3427 case Qualifiers::OCL_Weak: 3428 case Qualifiers::OCL_Autoreleasing: 3429 return true; 3430 3431 case Qualifiers::OCL_None: 3432 return T->isObjCLifetimeType(); 3433 } 3434 3435 llvm_unreachable("Unknown ObjC lifetime qualifier"); 3436} 3437 3438static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc, 3439 ArrayRef<TypeSourceInfo *> Args, 3440 SourceLocation RParenLoc) { 3441 switch (Kind) { 3442 case clang::TT_IsTriviallyConstructible: { 3443 // C++11 [meta.unary.prop]: 3444 // is_trivially_constructible is defined as: 3445 // 3446 // is_constructible<T, Args...>::value is true and the variable 3447 // definition for is_constructible, as defined below, is known to call no 3448 // operation that is not trivial. 3449 // 3450 // The predicate condition for a template specialization 3451 // is_constructible<T, Args...> shall be satisfied if and only if the 3452 // following variable definition would be well-formed for some invented 3453 // variable t: 3454 // 3455 // T t(create<Args>()...); 3456 if (Args.empty()) { 3457 S.Diag(KWLoc, diag::err_type_trait_arity) 3458 << 1 << 1 << 1 << (int)Args.size(); 3459 return false; 3460 } 3461 3462 bool SawVoid = false; 3463 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3464 if (Args[I]->getType()->isVoidType()) { 3465 SawVoid = true; 3466 continue; 3467 } 3468 3469 if (!Args[I]->getType()->isIncompleteType() && 3470 S.RequireCompleteType(KWLoc, Args[I]->getType(), 3471 diag::err_incomplete_type_used_in_type_trait_expr)) 3472 return false; 3473 } 3474 3475 // If any argument was 'void', of course it won't type-check. 3476 if (SawVoid) 3477 return false; 3478 3479 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs; 3480 SmallVector<Expr *, 2> ArgExprs; 3481 ArgExprs.reserve(Args.size() - 1); 3482 for (unsigned I = 1, N = Args.size(); I != N; ++I) { 3483 QualType T = Args[I]->getType(); 3484 if (T->isObjectType() || T->isFunctionType()) 3485 T = S.Context.getRValueReferenceType(T); 3486 OpaqueArgExprs.push_back( 3487 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(), 3488 T.getNonLValueExprType(S.Context), 3489 Expr::getValueKindForType(T))); 3490 ArgExprs.push_back(&OpaqueArgExprs.back()); 3491 } 3492 3493 // Perform the initialization in an unevaluated context within a SFINAE 3494 // trap at translation unit scope. 3495 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated); 3496 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true); 3497 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); 3498 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0])); 3499 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc, 3500 RParenLoc)); 3501 InitializationSequence Init(S, To, InitKind, ArgExprs); 3502 if (Init.Failed()) 3503 return false; 3504 3505 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs); 3506 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3507 return false; 3508 3509 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3510 // lifetime, this is a non-trivial construction. 3511 if (S.getLangOpts().ObjCAutoRefCount && 3512 hasNontrivialObjCLifetime(Args[0]->getType().getNonReferenceType())) 3513 return false; 3514 3515 // The initialization succeeded; now make sure there are no non-trivial 3516 // calls. 3517 return !Result.get()->hasNonTrivialCall(S.Context); 3518 } 3519 } 3520 3521 return false; 3522} 3523 3524ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3525 ArrayRef<TypeSourceInfo *> Args, 3526 SourceLocation RParenLoc) { 3527 bool Dependent = false; 3528 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3529 if (Args[I]->getType()->isDependentType()) { 3530 Dependent = true; 3531 break; 3532 } 3533 } 3534 3535 bool Value = false; 3536 if (!Dependent) 3537 Value = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc); 3538 3539 return TypeTraitExpr::Create(Context, Context.BoolTy, KWLoc, Kind, 3540 Args, RParenLoc, Value); 3541} 3542 3543ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3544 ArrayRef<ParsedType> Args, 3545 SourceLocation RParenLoc) { 3546 SmallVector<TypeSourceInfo *, 4> ConvertedArgs; 3547 ConvertedArgs.reserve(Args.size()); 3548 3549 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3550 TypeSourceInfo *TInfo; 3551 QualType T = GetTypeFromParser(Args[I], &TInfo); 3552 if (!TInfo) 3553 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc); 3554 3555 ConvertedArgs.push_back(TInfo); 3556 } 3557 3558 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc); 3559} 3560 3561static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3562 QualType LhsT, QualType RhsT, 3563 SourceLocation KeyLoc) { 3564 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3565 "Cannot evaluate traits of dependent types"); 3566 3567 switch(BTT) { 3568 case BTT_IsBaseOf: { 3569 // C++0x [meta.rel]p2 3570 // Base is a base class of Derived without regard to cv-qualifiers or 3571 // Base and Derived are not unions and name the same class type without 3572 // regard to cv-qualifiers. 3573 3574 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3575 if (!lhsRecord) return false; 3576 3577 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3578 if (!rhsRecord) return false; 3579 3580 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3581 == (lhsRecord == rhsRecord)); 3582 3583 if (lhsRecord == rhsRecord) 3584 return !lhsRecord->getDecl()->isUnion(); 3585 3586 // C++0x [meta.rel]p2: 3587 // If Base and Derived are class types and are different types 3588 // (ignoring possible cv-qualifiers) then Derived shall be a 3589 // complete type. 3590 if (Self.RequireCompleteType(KeyLoc, RhsT, 3591 diag::err_incomplete_type_used_in_type_trait_expr)) 3592 return false; 3593 3594 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3595 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3596 } 3597 case BTT_IsSame: 3598 return Self.Context.hasSameType(LhsT, RhsT); 3599 case BTT_TypeCompatible: 3600 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3601 RhsT.getUnqualifiedType()); 3602 case BTT_IsConvertible: 3603 case BTT_IsConvertibleTo: { 3604 // C++0x [meta.rel]p4: 3605 // Given the following function prototype: 3606 // 3607 // template <class T> 3608 // typename add_rvalue_reference<T>::type create(); 3609 // 3610 // the predicate condition for a template specialization 3611 // is_convertible<From, To> shall be satisfied if and only if 3612 // the return expression in the following code would be 3613 // well-formed, including any implicit conversions to the return 3614 // type of the function: 3615 // 3616 // To test() { 3617 // return create<From>(); 3618 // } 3619 // 3620 // Access checking is performed as if in a context unrelated to To and 3621 // From. Only the validity of the immediate context of the expression 3622 // of the return-statement (including conversions to the return type) 3623 // is considered. 3624 // 3625 // We model the initialization as a copy-initialization of a temporary 3626 // of the appropriate type, which for this expression is identical to the 3627 // return statement (since NRVO doesn't apply). 3628 3629 // Functions aren't allowed to return function or array types. 3630 if (RhsT->isFunctionType() || RhsT->isArrayType()) 3631 return false; 3632 3633 // A return statement in a void function must have void type. 3634 if (RhsT->isVoidType()) 3635 return LhsT->isVoidType(); 3636 3637 // A function definition requires a complete, non-abstract return type. 3638 if (Self.RequireCompleteType(KeyLoc, RhsT, 0) || 3639 Self.RequireNonAbstractType(KeyLoc, RhsT, 0)) 3640 return false; 3641 3642 // Compute the result of add_rvalue_reference. 3643 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3644 LhsT = Self.Context.getRValueReferenceType(LhsT); 3645 3646 // Build a fake source and destination for initialization. 3647 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3648 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3649 Expr::getValueKindForType(LhsT)); 3650 Expr *FromPtr = &From; 3651 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3652 SourceLocation())); 3653 3654 // Perform the initialization in an unevaluated context within a SFINAE 3655 // trap at translation unit scope. 3656 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3657 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3658 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3659 InitializationSequence Init(Self, To, Kind, FromPtr); 3660 if (Init.Failed()) 3661 return false; 3662 3663 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr); 3664 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3665 } 3666 3667 case BTT_IsTriviallyAssignable: { 3668 // C++11 [meta.unary.prop]p3: 3669 // is_trivially_assignable is defined as: 3670 // is_assignable<T, U>::value is true and the assignment, as defined by 3671 // is_assignable, is known to call no operation that is not trivial 3672 // 3673 // is_assignable is defined as: 3674 // The expression declval<T>() = declval<U>() is well-formed when 3675 // treated as an unevaluated operand (Clause 5). 3676 // 3677 // For both, T and U shall be complete types, (possibly cv-qualified) 3678 // void, or arrays of unknown bound. 3679 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() && 3680 Self.RequireCompleteType(KeyLoc, LhsT, 3681 diag::err_incomplete_type_used_in_type_trait_expr)) 3682 return false; 3683 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() && 3684 Self.RequireCompleteType(KeyLoc, RhsT, 3685 diag::err_incomplete_type_used_in_type_trait_expr)) 3686 return false; 3687 3688 // cv void is never assignable. 3689 if (LhsT->isVoidType() || RhsT->isVoidType()) 3690 return false; 3691 3692 // Build expressions that emulate the effect of declval<T>() and 3693 // declval<U>(). 3694 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3695 LhsT = Self.Context.getRValueReferenceType(LhsT); 3696 if (RhsT->isObjectType() || RhsT->isFunctionType()) 3697 RhsT = Self.Context.getRValueReferenceType(RhsT); 3698 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3699 Expr::getValueKindForType(LhsT)); 3700 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context), 3701 Expr::getValueKindForType(RhsT)); 3702 3703 // Attempt the assignment in an unevaluated context within a SFINAE 3704 // trap at translation unit scope. 3705 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3706 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3707 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3708 ExprResult Result = Self.BuildBinOp(/*S=*/0, KeyLoc, BO_Assign, &Lhs, &Rhs); 3709 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3710 return false; 3711 3712 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3713 // lifetime, this is a non-trivial assignment. 3714 if (Self.getLangOpts().ObjCAutoRefCount && 3715 hasNontrivialObjCLifetime(LhsT.getNonReferenceType())) 3716 return false; 3717 3718 return !Result.get()->hasNonTrivialCall(Self.Context); 3719 } 3720 } 3721 llvm_unreachable("Unknown type trait or not implemented"); 3722} 3723 3724ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3725 SourceLocation KWLoc, 3726 TypeSourceInfo *LhsTSInfo, 3727 TypeSourceInfo *RhsTSInfo, 3728 SourceLocation RParen) { 3729 QualType LhsT = LhsTSInfo->getType(); 3730 QualType RhsT = RhsTSInfo->getType(); 3731 3732 if (BTT == BTT_TypeCompatible) { 3733 if (getLangOpts().CPlusPlus) { 3734 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3735 << SourceRange(KWLoc, RParen); 3736 return ExprError(); 3737 } 3738 } 3739 3740 bool Value = false; 3741 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3742 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3743 3744 // Select trait result type. 3745 QualType ResultType; 3746 switch (BTT) { 3747 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3748 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3749 case BTT_IsSame: ResultType = Context.BoolTy; break; 3750 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3751 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3752 case BTT_IsTriviallyAssignable: ResultType = Context.BoolTy; 3753 } 3754 3755 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3756 RhsTSInfo, Value, RParen, 3757 ResultType)); 3758} 3759 3760ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3761 SourceLocation KWLoc, 3762 ParsedType Ty, 3763 Expr* DimExpr, 3764 SourceLocation RParen) { 3765 TypeSourceInfo *TSInfo; 3766 QualType T = GetTypeFromParser(Ty, &TSInfo); 3767 if (!TSInfo) 3768 TSInfo = Context.getTrivialTypeSourceInfo(T); 3769 3770 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3771} 3772 3773static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3774 QualType T, Expr *DimExpr, 3775 SourceLocation KeyLoc) { 3776 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3777 3778 switch(ATT) { 3779 case ATT_ArrayRank: 3780 if (T->isArrayType()) { 3781 unsigned Dim = 0; 3782 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3783 ++Dim; 3784 T = AT->getElementType(); 3785 } 3786 return Dim; 3787 } 3788 return 0; 3789 3790 case ATT_ArrayExtent: { 3791 llvm::APSInt Value; 3792 uint64_t Dim; 3793 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3794 diag::err_dimension_expr_not_constant_integer, 3795 false).isInvalid()) 3796 return 0; 3797 if (Value.isSigned() && Value.isNegative()) { 3798 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer) 3799 << DimExpr->getSourceRange(); 3800 return 0; 3801 } 3802 Dim = Value.getLimitedValue(); 3803 3804 if (T->isArrayType()) { 3805 unsigned D = 0; 3806 bool Matched = false; 3807 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3808 if (Dim == D) { 3809 Matched = true; 3810 break; 3811 } 3812 ++D; 3813 T = AT->getElementType(); 3814 } 3815 3816 if (Matched && T->isArrayType()) { 3817 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3818 return CAT->getSize().getLimitedValue(); 3819 } 3820 } 3821 return 0; 3822 } 3823 } 3824 llvm_unreachable("Unknown type trait or not implemented"); 3825} 3826 3827ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3828 SourceLocation KWLoc, 3829 TypeSourceInfo *TSInfo, 3830 Expr* DimExpr, 3831 SourceLocation RParen) { 3832 QualType T = TSInfo->getType(); 3833 3834 // FIXME: This should likely be tracked as an APInt to remove any host 3835 // assumptions about the width of size_t on the target. 3836 uint64_t Value = 0; 3837 if (!T->isDependentType()) 3838 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3839 3840 // While the specification for these traits from the Embarcadero C++ 3841 // compiler's documentation says the return type is 'unsigned int', Clang 3842 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3843 // compiler, there is no difference. On several other platforms this is an 3844 // important distinction. 3845 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3846 DimExpr, RParen, 3847 Context.getSizeType())); 3848} 3849 3850ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3851 SourceLocation KWLoc, 3852 Expr *Queried, 3853 SourceLocation RParen) { 3854 // If error parsing the expression, ignore. 3855 if (!Queried) 3856 return ExprError(); 3857 3858 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3859 3860 return Result; 3861} 3862 3863static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3864 switch (ET) { 3865 case ET_IsLValueExpr: return E->isLValue(); 3866 case ET_IsRValueExpr: return E->isRValue(); 3867 } 3868 llvm_unreachable("Expression trait not covered by switch"); 3869} 3870 3871ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3872 SourceLocation KWLoc, 3873 Expr *Queried, 3874 SourceLocation RParen) { 3875 if (Queried->isTypeDependent()) { 3876 // Delay type-checking for type-dependent expressions. 3877 } else if (Queried->getType()->isPlaceholderType()) { 3878 ExprResult PE = CheckPlaceholderExpr(Queried); 3879 if (PE.isInvalid()) return ExprError(); 3880 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3881 } 3882 3883 bool Value = EvaluateExpressionTrait(ET, Queried); 3884 3885 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3886 RParen, Context.BoolTy)); 3887} 3888 3889QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3890 ExprValueKind &VK, 3891 SourceLocation Loc, 3892 bool isIndirect) { 3893 assert(!LHS.get()->getType()->isPlaceholderType() && 3894 !RHS.get()->getType()->isPlaceholderType() && 3895 "placeholders should have been weeded out by now"); 3896 3897 // The LHS undergoes lvalue conversions if this is ->*. 3898 if (isIndirect) { 3899 LHS = DefaultLvalueConversion(LHS.take()); 3900 if (LHS.isInvalid()) return QualType(); 3901 } 3902 3903 // The RHS always undergoes lvalue conversions. 3904 RHS = DefaultLvalueConversion(RHS.take()); 3905 if (RHS.isInvalid()) return QualType(); 3906 3907 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3908 // C++ 5.5p2 3909 // The binary operator .* [p3: ->*] binds its second operand, which shall 3910 // be of type "pointer to member of T" (where T is a completely-defined 3911 // class type) [...] 3912 QualType RHSType = RHS.get()->getType(); 3913 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3914 if (!MemPtr) { 3915 Diag(Loc, diag::err_bad_memptr_rhs) 3916 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3917 return QualType(); 3918 } 3919 3920 QualType Class(MemPtr->getClass(), 0); 3921 3922 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3923 // member pointer points must be completely-defined. However, there is no 3924 // reason for this semantic distinction, and the rule is not enforced by 3925 // other compilers. Therefore, we do not check this property, as it is 3926 // likely to be considered a defect. 3927 3928 // C++ 5.5p2 3929 // [...] to its first operand, which shall be of class T or of a class of 3930 // which T is an unambiguous and accessible base class. [p3: a pointer to 3931 // such a class] 3932 QualType LHSType = LHS.get()->getType(); 3933 if (isIndirect) { 3934 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3935 LHSType = Ptr->getPointeeType(); 3936 else { 3937 Diag(Loc, diag::err_bad_memptr_lhs) 3938 << OpSpelling << 1 << LHSType 3939 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3940 return QualType(); 3941 } 3942 } 3943 3944 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3945 // If we want to check the hierarchy, we need a complete type. 3946 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs, 3947 OpSpelling, (int)isIndirect)) { 3948 return QualType(); 3949 } 3950 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3951 /*DetectVirtual=*/false); 3952 // FIXME: Would it be useful to print full ambiguity paths, or is that 3953 // overkill? 3954 if (!IsDerivedFrom(LHSType, Class, Paths) || 3955 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3956 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3957 << (int)isIndirect << LHS.get()->getType(); 3958 return QualType(); 3959 } 3960 // Cast LHS to type of use. 3961 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3962 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3963 3964 CXXCastPath BasePath; 3965 BuildBasePathArray(Paths, BasePath); 3966 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3967 &BasePath); 3968 } 3969 3970 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3971 // Diagnose use of pointer-to-member type which when used as 3972 // the functional cast in a pointer-to-member expression. 3973 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3974 return QualType(); 3975 } 3976 3977 // C++ 5.5p2 3978 // The result is an object or a function of the type specified by the 3979 // second operand. 3980 // The cv qualifiers are the union of those in the pointer and the left side, 3981 // in accordance with 5.5p5 and 5.2.5. 3982 QualType Result = MemPtr->getPointeeType(); 3983 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3984 3985 // C++0x [expr.mptr.oper]p6: 3986 // In a .* expression whose object expression is an rvalue, the program is 3987 // ill-formed if the second operand is a pointer to member function with 3988 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3989 // expression is an lvalue, the program is ill-formed if the second operand 3990 // is a pointer to member function with ref-qualifier &&. 3991 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3992 switch (Proto->getRefQualifier()) { 3993 case RQ_None: 3994 // Do nothing 3995 break; 3996 3997 case RQ_LValue: 3998 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3999 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 4000 << RHSType << 1 << LHS.get()->getSourceRange(); 4001 break; 4002 4003 case RQ_RValue: 4004 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 4005 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 4006 << RHSType << 0 << LHS.get()->getSourceRange(); 4007 break; 4008 } 4009 } 4010 4011 // C++ [expr.mptr.oper]p6: 4012 // The result of a .* expression whose second operand is a pointer 4013 // to a data member is of the same value category as its 4014 // first operand. The result of a .* expression whose second 4015 // operand is a pointer to a member function is a prvalue. The 4016 // result of an ->* expression is an lvalue if its second operand 4017 // is a pointer to data member and a prvalue otherwise. 4018 if (Result->isFunctionType()) { 4019 VK = VK_RValue; 4020 return Context.BoundMemberTy; 4021 } else if (isIndirect) { 4022 VK = VK_LValue; 4023 } else { 4024 VK = LHS.get()->getValueKind(); 4025 } 4026 4027 return Result; 4028} 4029 4030/// \brief Try to convert a type to another according to C++0x 5.16p3. 4031/// 4032/// This is part of the parameter validation for the ? operator. If either 4033/// value operand is a class type, the two operands are attempted to be 4034/// converted to each other. This function does the conversion in one direction. 4035/// It returns true if the program is ill-formed and has already been diagnosed 4036/// as such. 4037static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 4038 SourceLocation QuestionLoc, 4039 bool &HaveConversion, 4040 QualType &ToType) { 4041 HaveConversion = false; 4042 ToType = To->getType(); 4043 4044 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 4045 SourceLocation()); 4046 // C++0x 5.16p3 4047 // The process for determining whether an operand expression E1 of type T1 4048 // can be converted to match an operand expression E2 of type T2 is defined 4049 // as follows: 4050 // -- If E2 is an lvalue: 4051 bool ToIsLvalue = To->isLValue(); 4052 if (ToIsLvalue) { 4053 // E1 can be converted to match E2 if E1 can be implicitly converted to 4054 // type "lvalue reference to T2", subject to the constraint that in the 4055 // conversion the reference must bind directly to E1. 4056 QualType T = Self.Context.getLValueReferenceType(ToType); 4057 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 4058 4059 InitializationSequence InitSeq(Self, Entity, Kind, From); 4060 if (InitSeq.isDirectReferenceBinding()) { 4061 ToType = T; 4062 HaveConversion = true; 4063 return false; 4064 } 4065 4066 if (InitSeq.isAmbiguous()) 4067 return InitSeq.Diagnose(Self, Entity, Kind, From); 4068 } 4069 4070 // -- If E2 is an rvalue, or if the conversion above cannot be done: 4071 // -- if E1 and E2 have class type, and the underlying class types are 4072 // the same or one is a base class of the other: 4073 QualType FTy = From->getType(); 4074 QualType TTy = To->getType(); 4075 const RecordType *FRec = FTy->getAs<RecordType>(); 4076 const RecordType *TRec = TTy->getAs<RecordType>(); 4077 bool FDerivedFromT = FRec && TRec && FRec != TRec && 4078 Self.IsDerivedFrom(FTy, TTy); 4079 if (FRec && TRec && 4080 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 4081 // E1 can be converted to match E2 if the class of T2 is the 4082 // same type as, or a base class of, the class of T1, and 4083 // [cv2 > cv1]. 4084 if (FRec == TRec || FDerivedFromT) { 4085 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 4086 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 4087 InitializationSequence InitSeq(Self, Entity, Kind, From); 4088 if (InitSeq) { 4089 HaveConversion = true; 4090 return false; 4091 } 4092 4093 if (InitSeq.isAmbiguous()) 4094 return InitSeq.Diagnose(Self, Entity, Kind, From); 4095 } 4096 } 4097 4098 return false; 4099 } 4100 4101 // -- Otherwise: E1 can be converted to match E2 if E1 can be 4102 // implicitly converted to the type that expression E2 would have 4103 // if E2 were converted to an rvalue (or the type it has, if E2 is 4104 // an rvalue). 4105 // 4106 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 4107 // to the array-to-pointer or function-to-pointer conversions. 4108 if (!TTy->getAs<TagType>()) 4109 TTy = TTy.getUnqualifiedType(); 4110 4111 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 4112 InitializationSequence InitSeq(Self, Entity, Kind, From); 4113 HaveConversion = !InitSeq.Failed(); 4114 ToType = TTy; 4115 if (InitSeq.isAmbiguous()) 4116 return InitSeq.Diagnose(Self, Entity, Kind, From); 4117 4118 return false; 4119} 4120 4121/// \brief Try to find a common type for two according to C++0x 5.16p5. 4122/// 4123/// This is part of the parameter validation for the ? operator. If either 4124/// value operand is a class type, overload resolution is used to find a 4125/// conversion to a common type. 4126static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 4127 SourceLocation QuestionLoc) { 4128 Expr *Args[2] = { LHS.get(), RHS.get() }; 4129 OverloadCandidateSet CandidateSet(QuestionLoc); 4130 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 4131 CandidateSet); 4132 4133 OverloadCandidateSet::iterator Best; 4134 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 4135 case OR_Success: { 4136 // We found a match. Perform the conversions on the arguments and move on. 4137 ExprResult LHSRes = 4138 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 4139 Best->Conversions[0], Sema::AA_Converting); 4140 if (LHSRes.isInvalid()) 4141 break; 4142 LHS = LHSRes; 4143 4144 ExprResult RHSRes = 4145 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 4146 Best->Conversions[1], Sema::AA_Converting); 4147 if (RHSRes.isInvalid()) 4148 break; 4149 RHS = RHSRes; 4150 if (Best->Function) 4151 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 4152 return false; 4153 } 4154 4155 case OR_No_Viable_Function: 4156 4157 // Emit a better diagnostic if one of the expressions is a null pointer 4158 // constant and the other is a pointer type. In this case, the user most 4159 // likely forgot to take the address of the other expression. 4160 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4161 return true; 4162 4163 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4164 << LHS.get()->getType() << RHS.get()->getType() 4165 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4166 return true; 4167 4168 case OR_Ambiguous: 4169 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 4170 << LHS.get()->getType() << RHS.get()->getType() 4171 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4172 // FIXME: Print the possible common types by printing the return types of 4173 // the viable candidates. 4174 break; 4175 4176 case OR_Deleted: 4177 llvm_unreachable("Conditional operator has only built-in overloads"); 4178 } 4179 return true; 4180} 4181 4182/// \brief Perform an "extended" implicit conversion as returned by 4183/// TryClassUnification. 4184static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 4185 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 4186 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 4187 SourceLocation()); 4188 Expr *Arg = E.take(); 4189 InitializationSequence InitSeq(Self, Entity, Kind, Arg); 4190 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg); 4191 if (Result.isInvalid()) 4192 return true; 4193 4194 E = Result; 4195 return false; 4196} 4197 4198/// \brief Check the operands of ?: under C++ semantics. 4199/// 4200/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 4201/// extension. In this case, LHS == Cond. (But they're not aliases.) 4202QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 4203 ExprResult &RHS, ExprValueKind &VK, 4204 ExprObjectKind &OK, 4205 SourceLocation QuestionLoc) { 4206 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 4207 // interface pointers. 4208 4209 // C++11 [expr.cond]p1 4210 // The first expression is contextually converted to bool. 4211 if (!Cond.get()->isTypeDependent()) { 4212 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 4213 if (CondRes.isInvalid()) 4214 return QualType(); 4215 Cond = CondRes; 4216 } 4217 4218 // Assume r-value. 4219 VK = VK_RValue; 4220 OK = OK_Ordinary; 4221 4222 // Either of the arguments dependent? 4223 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 4224 return Context.DependentTy; 4225 4226 // C++11 [expr.cond]p2 4227 // If either the second or the third operand has type (cv) void, ... 4228 QualType LTy = LHS.get()->getType(); 4229 QualType RTy = RHS.get()->getType(); 4230 bool LVoid = LTy->isVoidType(); 4231 bool RVoid = RTy->isVoidType(); 4232 if (LVoid || RVoid) { 4233 // ... then the [l2r] conversions are performed on the second and third 4234 // operands ... 4235 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4236 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4237 if (LHS.isInvalid() || RHS.isInvalid()) 4238 return QualType(); 4239 4240 // Finish off the lvalue-to-rvalue conversion by copy-initializing a 4241 // temporary if necessary. DefaultFunctionArrayLvalueConversion doesn't 4242 // do this part for us. 4243 ExprResult &NonVoid = LVoid ? RHS : LHS; 4244 if (NonVoid.get()->getType()->isRecordType() && 4245 NonVoid.get()->isGLValue()) { 4246 if (RequireNonAbstractType(QuestionLoc, NonVoid.get()->getType(), 4247 diag::err_allocation_of_abstract_type)) 4248 return QualType(); 4249 InitializedEntity Entity = 4250 InitializedEntity::InitializeTemporary(NonVoid.get()->getType()); 4251 NonVoid = PerformCopyInitialization(Entity, SourceLocation(), NonVoid); 4252 if (NonVoid.isInvalid()) 4253 return QualType(); 4254 } 4255 4256 LTy = LHS.get()->getType(); 4257 RTy = RHS.get()->getType(); 4258 4259 // ... and one of the following shall hold: 4260 // -- The second or the third operand (but not both) is a throw- 4261 // expression; the result is of the type of the other and is a prvalue. 4262 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 4263 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 4264 if (LThrow && !RThrow) 4265 return RTy; 4266 if (RThrow && !LThrow) 4267 return LTy; 4268 4269 // -- Both the second and third operands have type void; the result is of 4270 // type void and is a prvalue. 4271 if (LVoid && RVoid) 4272 return Context.VoidTy; 4273 4274 // Neither holds, error. 4275 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 4276 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 4277 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4278 return QualType(); 4279 } 4280 4281 // Neither is void. 4282 4283 // C++11 [expr.cond]p3 4284 // Otherwise, if the second and third operand have different types, and 4285 // either has (cv) class type [...] an attempt is made to convert each of 4286 // those operands to the type of the other. 4287 if (!Context.hasSameType(LTy, RTy) && 4288 (LTy->isRecordType() || RTy->isRecordType())) { 4289 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 4290 // These return true if a single direction is already ambiguous. 4291 QualType L2RType, R2LType; 4292 bool HaveL2R, HaveR2L; 4293 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 4294 return QualType(); 4295 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 4296 return QualType(); 4297 4298 // If both can be converted, [...] the program is ill-formed. 4299 if (HaveL2R && HaveR2L) { 4300 Diag(QuestionLoc, diag::err_conditional_ambiguous) 4301 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4302 return QualType(); 4303 } 4304 4305 // If exactly one conversion is possible, that conversion is applied to 4306 // the chosen operand and the converted operands are used in place of the 4307 // original operands for the remainder of this section. 4308 if (HaveL2R) { 4309 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 4310 return QualType(); 4311 LTy = LHS.get()->getType(); 4312 } else if (HaveR2L) { 4313 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 4314 return QualType(); 4315 RTy = RHS.get()->getType(); 4316 } 4317 } 4318 4319 // C++11 [expr.cond]p3 4320 // if both are glvalues of the same value category and the same type except 4321 // for cv-qualification, an attempt is made to convert each of those 4322 // operands to the type of the other. 4323 ExprValueKind LVK = LHS.get()->getValueKind(); 4324 ExprValueKind RVK = RHS.get()->getValueKind(); 4325 if (!Context.hasSameType(LTy, RTy) && 4326 Context.hasSameUnqualifiedType(LTy, RTy) && 4327 LVK == RVK && LVK != VK_RValue) { 4328 // Since the unqualified types are reference-related and we require the 4329 // result to be as if a reference bound directly, the only conversion 4330 // we can perform is to add cv-qualifiers. 4331 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers()); 4332 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers()); 4333 if (RCVR.isStrictSupersetOf(LCVR)) { 4334 LHS = ImpCastExprToType(LHS.take(), RTy, CK_NoOp, LVK); 4335 LTy = LHS.get()->getType(); 4336 } 4337 else if (LCVR.isStrictSupersetOf(RCVR)) { 4338 RHS = ImpCastExprToType(RHS.take(), LTy, CK_NoOp, RVK); 4339 RTy = RHS.get()->getType(); 4340 } 4341 } 4342 4343 // C++11 [expr.cond]p4 4344 // If the second and third operands are glvalues of the same value 4345 // category and have the same type, the result is of that type and 4346 // value category and it is a bit-field if the second or the third 4347 // operand is a bit-field, or if both are bit-fields. 4348 // We only extend this to bitfields, not to the crazy other kinds of 4349 // l-values. 4350 bool Same = Context.hasSameType(LTy, RTy); 4351 if (Same && LVK == RVK && LVK != VK_RValue && 4352 LHS.get()->isOrdinaryOrBitFieldObject() && 4353 RHS.get()->isOrdinaryOrBitFieldObject()) { 4354 VK = LHS.get()->getValueKind(); 4355 if (LHS.get()->getObjectKind() == OK_BitField || 4356 RHS.get()->getObjectKind() == OK_BitField) 4357 OK = OK_BitField; 4358 return LTy; 4359 } 4360 4361 // C++11 [expr.cond]p5 4362 // Otherwise, the result is a prvalue. If the second and third operands 4363 // do not have the same type, and either has (cv) class type, ... 4364 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 4365 // ... overload resolution is used to determine the conversions (if any) 4366 // to be applied to the operands. If the overload resolution fails, the 4367 // program is ill-formed. 4368 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 4369 return QualType(); 4370 } 4371 4372 // C++11 [expr.cond]p6 4373 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard 4374 // conversions are performed on the second and third operands. 4375 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4376 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4377 if (LHS.isInvalid() || RHS.isInvalid()) 4378 return QualType(); 4379 LTy = LHS.get()->getType(); 4380 RTy = RHS.get()->getType(); 4381 4382 // After those conversions, one of the following shall hold: 4383 // -- The second and third operands have the same type; the result 4384 // is of that type. If the operands have class type, the result 4385 // is a prvalue temporary of the result type, which is 4386 // copy-initialized from either the second operand or the third 4387 // operand depending on the value of the first operand. 4388 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 4389 if (LTy->isRecordType()) { 4390 // The operands have class type. Make a temporary copy. 4391 if (RequireNonAbstractType(QuestionLoc, LTy, 4392 diag::err_allocation_of_abstract_type)) 4393 return QualType(); 4394 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 4395 4396 ExprResult LHSCopy = PerformCopyInitialization(Entity, 4397 SourceLocation(), 4398 LHS); 4399 if (LHSCopy.isInvalid()) 4400 return QualType(); 4401 4402 ExprResult RHSCopy = PerformCopyInitialization(Entity, 4403 SourceLocation(), 4404 RHS); 4405 if (RHSCopy.isInvalid()) 4406 return QualType(); 4407 4408 LHS = LHSCopy; 4409 RHS = RHSCopy; 4410 } 4411 4412 return LTy; 4413 } 4414 4415 // Extension: conditional operator involving vector types. 4416 if (LTy->isVectorType() || RTy->isVectorType()) 4417 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4418 4419 // -- The second and third operands have arithmetic or enumeration type; 4420 // the usual arithmetic conversions are performed to bring them to a 4421 // common type, and the result is of that type. 4422 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 4423 UsualArithmeticConversions(LHS, RHS); 4424 if (LHS.isInvalid() || RHS.isInvalid()) 4425 return QualType(); 4426 return LHS.get()->getType(); 4427 } 4428 4429 // -- The second and third operands have pointer type, or one has pointer 4430 // type and the other is a null pointer constant, or both are null 4431 // pointer constants, at least one of which is non-integral; pointer 4432 // conversions and qualification conversions are performed to bring them 4433 // to their composite pointer type. The result is of the composite 4434 // pointer type. 4435 // -- The second and third operands have pointer to member type, or one has 4436 // pointer to member type and the other is a null pointer constant; 4437 // pointer to member conversions and qualification conversions are 4438 // performed to bring them to a common type, whose cv-qualification 4439 // shall match the cv-qualification of either the second or the third 4440 // operand. The result is of the common type. 4441 bool NonStandardCompositeType = false; 4442 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 4443 isSFINAEContext()? 0 : &NonStandardCompositeType); 4444 if (!Composite.isNull()) { 4445 if (NonStandardCompositeType) 4446 Diag(QuestionLoc, 4447 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 4448 << LTy << RTy << Composite 4449 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4450 4451 return Composite; 4452 } 4453 4454 // Similarly, attempt to find composite type of two objective-c pointers. 4455 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 4456 if (!Composite.isNull()) 4457 return Composite; 4458 4459 // Check if we are using a null with a non-pointer type. 4460 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4461 return QualType(); 4462 4463 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4464 << LHS.get()->getType() << RHS.get()->getType() 4465 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4466 return QualType(); 4467} 4468 4469/// \brief Find a merged pointer type and convert the two expressions to it. 4470/// 4471/// This finds the composite pointer type (or member pointer type) for @p E1 4472/// and @p E2 according to C++11 5.9p2. It converts both expressions to this 4473/// type and returns it. 4474/// It does not emit diagnostics. 4475/// 4476/// \param Loc The location of the operator requiring these two expressions to 4477/// be converted to the composite pointer type. 4478/// 4479/// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4480/// a non-standard (but still sane) composite type to which both expressions 4481/// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4482/// will be set true. 4483QualType Sema::FindCompositePointerType(SourceLocation Loc, 4484 Expr *&E1, Expr *&E2, 4485 bool *NonStandardCompositeType) { 4486 if (NonStandardCompositeType) 4487 *NonStandardCompositeType = false; 4488 4489 assert(getLangOpts().CPlusPlus && "This function assumes C++"); 4490 QualType T1 = E1->getType(), T2 = E2->getType(); 4491 4492 // C++11 5.9p2 4493 // Pointer conversions and qualification conversions are performed on 4494 // pointer operands to bring them to their composite pointer type. If 4495 // one operand is a null pointer constant, the composite pointer type is 4496 // std::nullptr_t if the other operand is also a null pointer constant or, 4497 // if the other operand is a pointer, the type of the other operand. 4498 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4499 !T2->isAnyPointerType() && !T2->isMemberPointerType()) { 4500 if (T1->isNullPtrType() && 4501 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4502 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4503 return T1; 4504 } 4505 if (T2->isNullPtrType() && 4506 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4507 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4508 return T2; 4509 } 4510 return QualType(); 4511 } 4512 4513 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4514 if (T2->isMemberPointerType()) 4515 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4516 else 4517 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4518 return T2; 4519 } 4520 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4521 if (T1->isMemberPointerType()) 4522 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4523 else 4524 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4525 return T1; 4526 } 4527 4528 // Now both have to be pointers or member pointers. 4529 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4530 (!T2->isPointerType() && !T2->isMemberPointerType())) 4531 return QualType(); 4532 4533 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4534 // the other has type "pointer to cv2 T" and the composite pointer type is 4535 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4536 // Otherwise, the composite pointer type is a pointer type similar to the 4537 // type of one of the operands, with a cv-qualification signature that is 4538 // the union of the cv-qualification signatures of the operand types. 4539 // In practice, the first part here is redundant; it's subsumed by the second. 4540 // What we do here is, we build the two possible composite types, and try the 4541 // conversions in both directions. If only one works, or if the two composite 4542 // types are the same, we have succeeded. 4543 // FIXME: extended qualifiers? 4544 typedef SmallVector<unsigned, 4> QualifierVector; 4545 QualifierVector QualifierUnion; 4546 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4547 ContainingClassVector; 4548 ContainingClassVector MemberOfClass; 4549 QualType Composite1 = Context.getCanonicalType(T1), 4550 Composite2 = Context.getCanonicalType(T2); 4551 unsigned NeedConstBefore = 0; 4552 do { 4553 const PointerType *Ptr1, *Ptr2; 4554 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4555 (Ptr2 = Composite2->getAs<PointerType>())) { 4556 Composite1 = Ptr1->getPointeeType(); 4557 Composite2 = Ptr2->getPointeeType(); 4558 4559 // If we're allowed to create a non-standard composite type, keep track 4560 // of where we need to fill in additional 'const' qualifiers. 4561 if (NonStandardCompositeType && 4562 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4563 NeedConstBefore = QualifierUnion.size(); 4564 4565 QualifierUnion.push_back( 4566 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4567 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4568 continue; 4569 } 4570 4571 const MemberPointerType *MemPtr1, *MemPtr2; 4572 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4573 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4574 Composite1 = MemPtr1->getPointeeType(); 4575 Composite2 = MemPtr2->getPointeeType(); 4576 4577 // If we're allowed to create a non-standard composite type, keep track 4578 // of where we need to fill in additional 'const' qualifiers. 4579 if (NonStandardCompositeType && 4580 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4581 NeedConstBefore = QualifierUnion.size(); 4582 4583 QualifierUnion.push_back( 4584 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4585 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4586 MemPtr2->getClass())); 4587 continue; 4588 } 4589 4590 // FIXME: block pointer types? 4591 4592 // Cannot unwrap any more types. 4593 break; 4594 } while (true); 4595 4596 if (NeedConstBefore && NonStandardCompositeType) { 4597 // Extension: Add 'const' to qualifiers that come before the first qualifier 4598 // mismatch, so that our (non-standard!) composite type meets the 4599 // requirements of C++ [conv.qual]p4 bullet 3. 4600 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4601 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4602 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4603 *NonStandardCompositeType = true; 4604 } 4605 } 4606 } 4607 4608 // Rewrap the composites as pointers or member pointers with the union CVRs. 4609 ContainingClassVector::reverse_iterator MOC 4610 = MemberOfClass.rbegin(); 4611 for (QualifierVector::reverse_iterator 4612 I = QualifierUnion.rbegin(), 4613 E = QualifierUnion.rend(); 4614 I != E; (void)++I, ++MOC) { 4615 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4616 if (MOC->first && MOC->second) { 4617 // Rebuild member pointer type 4618 Composite1 = Context.getMemberPointerType( 4619 Context.getQualifiedType(Composite1, Quals), 4620 MOC->first); 4621 Composite2 = Context.getMemberPointerType( 4622 Context.getQualifiedType(Composite2, Quals), 4623 MOC->second); 4624 } else { 4625 // Rebuild pointer type 4626 Composite1 4627 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4628 Composite2 4629 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4630 } 4631 } 4632 4633 // Try to convert to the first composite pointer type. 4634 InitializedEntity Entity1 4635 = InitializedEntity::InitializeTemporary(Composite1); 4636 InitializationKind Kind 4637 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4638 InitializationSequence E1ToC1(*this, Entity1, Kind, E1); 4639 InitializationSequence E2ToC1(*this, Entity1, Kind, E2); 4640 4641 if (E1ToC1 && E2ToC1) { 4642 // Conversion to Composite1 is viable. 4643 if (!Context.hasSameType(Composite1, Composite2)) { 4644 // Composite2 is a different type from Composite1. Check whether 4645 // Composite2 is also viable. 4646 InitializedEntity Entity2 4647 = InitializedEntity::InitializeTemporary(Composite2); 4648 InitializationSequence E1ToC2(*this, Entity2, Kind, E1); 4649 InitializationSequence E2ToC2(*this, Entity2, Kind, E2); 4650 if (E1ToC2 && E2ToC2) { 4651 // Both Composite1 and Composite2 are viable and are different; 4652 // this is an ambiguity. 4653 return QualType(); 4654 } 4655 } 4656 4657 // Convert E1 to Composite1 4658 ExprResult E1Result 4659 = E1ToC1.Perform(*this, Entity1, Kind, E1); 4660 if (E1Result.isInvalid()) 4661 return QualType(); 4662 E1 = E1Result.takeAs<Expr>(); 4663 4664 // Convert E2 to Composite1 4665 ExprResult E2Result 4666 = E2ToC1.Perform(*this, Entity1, Kind, E2); 4667 if (E2Result.isInvalid()) 4668 return QualType(); 4669 E2 = E2Result.takeAs<Expr>(); 4670 4671 return Composite1; 4672 } 4673 4674 // Check whether Composite2 is viable. 4675 InitializedEntity Entity2 4676 = InitializedEntity::InitializeTemporary(Composite2); 4677 InitializationSequence E1ToC2(*this, Entity2, Kind, E1); 4678 InitializationSequence E2ToC2(*this, Entity2, Kind, E2); 4679 if (!E1ToC2 || !E2ToC2) 4680 return QualType(); 4681 4682 // Convert E1 to Composite2 4683 ExprResult E1Result 4684 = E1ToC2.Perform(*this, Entity2, Kind, E1); 4685 if (E1Result.isInvalid()) 4686 return QualType(); 4687 E1 = E1Result.takeAs<Expr>(); 4688 4689 // Convert E2 to Composite2 4690 ExprResult E2Result 4691 = E2ToC2.Perform(*this, Entity2, Kind, E2); 4692 if (E2Result.isInvalid()) 4693 return QualType(); 4694 E2 = E2Result.takeAs<Expr>(); 4695 4696 return Composite2; 4697} 4698 4699ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4700 if (!E) 4701 return ExprError(); 4702 4703 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4704 4705 // If the result is a glvalue, we shouldn't bind it. 4706 if (!E->isRValue()) 4707 return Owned(E); 4708 4709 // In ARC, calls that return a retainable type can return retained, 4710 // in which case we have to insert a consuming cast. 4711 if (getLangOpts().ObjCAutoRefCount && 4712 E->getType()->isObjCRetainableType()) { 4713 4714 bool ReturnsRetained; 4715 4716 // For actual calls, we compute this by examining the type of the 4717 // called value. 4718 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4719 Expr *Callee = Call->getCallee()->IgnoreParens(); 4720 QualType T = Callee->getType(); 4721 4722 if (T == Context.BoundMemberTy) { 4723 // Handle pointer-to-members. 4724 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4725 T = BinOp->getRHS()->getType(); 4726 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4727 T = Mem->getMemberDecl()->getType(); 4728 } 4729 4730 if (const PointerType *Ptr = T->getAs<PointerType>()) 4731 T = Ptr->getPointeeType(); 4732 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4733 T = Ptr->getPointeeType(); 4734 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4735 T = MemPtr->getPointeeType(); 4736 4737 const FunctionType *FTy = T->getAs<FunctionType>(); 4738 assert(FTy && "call to value not of function type?"); 4739 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4740 4741 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4742 // type always produce a +1 object. 4743 } else if (isa<StmtExpr>(E)) { 4744 ReturnsRetained = true; 4745 4746 // We hit this case with the lambda conversion-to-block optimization; 4747 // we don't want any extra casts here. 4748 } else if (isa<CastExpr>(E) && 4749 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) { 4750 return Owned(E); 4751 4752 // For message sends and property references, we try to find an 4753 // actual method. FIXME: we should infer retention by selector in 4754 // cases where we don't have an actual method. 4755 } else { 4756 ObjCMethodDecl *D = 0; 4757 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4758 D = Send->getMethodDecl(); 4759 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) { 4760 D = BoxedExpr->getBoxingMethod(); 4761 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) { 4762 D = ArrayLit->getArrayWithObjectsMethod(); 4763 } else if (ObjCDictionaryLiteral *DictLit 4764 = dyn_cast<ObjCDictionaryLiteral>(E)) { 4765 D = DictLit->getDictWithObjectsMethod(); 4766 } 4767 4768 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4769 4770 // Don't do reclaims on performSelector calls; despite their 4771 // return type, the invoked method doesn't necessarily actually 4772 // return an object. 4773 if (!ReturnsRetained && 4774 D && D->getMethodFamily() == OMF_performSelector) 4775 return Owned(E); 4776 } 4777 4778 // Don't reclaim an object of Class type. 4779 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4780 return Owned(E); 4781 4782 ExprNeedsCleanups = true; 4783 4784 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4785 : CK_ARCReclaimReturnedObject); 4786 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4787 VK_RValue)); 4788 } 4789 4790 if (!getLangOpts().CPlusPlus) 4791 return Owned(E); 4792 4793 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4794 // a fast path for the common case that the type is directly a RecordType. 4795 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4796 const RecordType *RT = 0; 4797 while (!RT) { 4798 switch (T->getTypeClass()) { 4799 case Type::Record: 4800 RT = cast<RecordType>(T); 4801 break; 4802 case Type::ConstantArray: 4803 case Type::IncompleteArray: 4804 case Type::VariableArray: 4805 case Type::DependentSizedArray: 4806 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4807 break; 4808 default: 4809 return Owned(E); 4810 } 4811 } 4812 4813 // That should be enough to guarantee that this type is complete, if we're 4814 // not processing a decltype expression. 4815 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4816 if (RD->isInvalidDecl() || RD->isDependentContext()) 4817 return Owned(E); 4818 4819 bool IsDecltype = ExprEvalContexts.back().IsDecltype; 4820 CXXDestructorDecl *Destructor = IsDecltype ? 0 : LookupDestructor(RD); 4821 4822 if (Destructor) { 4823 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4824 CheckDestructorAccess(E->getExprLoc(), Destructor, 4825 PDiag(diag::err_access_dtor_temp) 4826 << E->getType()); 4827 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc())) 4828 return ExprError(); 4829 4830 // If destructor is trivial, we can avoid the extra copy. 4831 if (Destructor->isTrivial()) 4832 return Owned(E); 4833 4834 // We need a cleanup, but we don't need to remember the temporary. 4835 ExprNeedsCleanups = true; 4836 } 4837 4838 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4839 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E); 4840 4841 if (IsDecltype) 4842 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind); 4843 4844 return Owned(Bind); 4845} 4846 4847ExprResult 4848Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4849 if (SubExpr.isInvalid()) 4850 return ExprError(); 4851 4852 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4853} 4854 4855Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4856 assert(SubExpr && "sub expression can't be null!"); 4857 4858 CleanupVarDeclMarking(); 4859 4860 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4861 assert(ExprCleanupObjects.size() >= FirstCleanup); 4862 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4863 if (!ExprNeedsCleanups) 4864 return SubExpr; 4865 4866 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4867 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4868 ExprCleanupObjects.size() - FirstCleanup); 4869 4870 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4871 DiscardCleanupsInEvaluationContext(); 4872 4873 return E; 4874} 4875 4876Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4877 assert(SubStmt && "sub statement can't be null!"); 4878 4879 CleanupVarDeclMarking(); 4880 4881 if (!ExprNeedsCleanups) 4882 return SubStmt; 4883 4884 // FIXME: In order to attach the temporaries, wrap the statement into 4885 // a StmtExpr; currently this is only used for asm statements. 4886 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4887 // a new AsmStmtWithTemporaries. 4888 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt, 4889 SourceLocation(), 4890 SourceLocation()); 4891 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4892 SourceLocation()); 4893 return MaybeCreateExprWithCleanups(E); 4894} 4895 4896/// Process the expression contained within a decltype. For such expressions, 4897/// certain semantic checks on temporaries are delayed until this point, and 4898/// are omitted for the 'topmost' call in the decltype expression. If the 4899/// topmost call bound a temporary, strip that temporary off the expression. 4900ExprResult Sema::ActOnDecltypeExpression(Expr *E) { 4901 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression"); 4902 4903 // C++11 [expr.call]p11: 4904 // If a function call is a prvalue of object type, 4905 // -- if the function call is either 4906 // -- the operand of a decltype-specifier, or 4907 // -- the right operand of a comma operator that is the operand of a 4908 // decltype-specifier, 4909 // a temporary object is not introduced for the prvalue. 4910 4911 // Recursively rebuild ParenExprs and comma expressions to strip out the 4912 // outermost CXXBindTemporaryExpr, if any. 4913 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 4914 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr()); 4915 if (SubExpr.isInvalid()) 4916 return ExprError(); 4917 if (SubExpr.get() == PE->getSubExpr()) 4918 return Owned(E); 4919 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.take()); 4920 } 4921 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 4922 if (BO->getOpcode() == BO_Comma) { 4923 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS()); 4924 if (RHS.isInvalid()) 4925 return ExprError(); 4926 if (RHS.get() == BO->getRHS()) 4927 return Owned(E); 4928 return Owned(new (Context) BinaryOperator(BO->getLHS(), RHS.take(), 4929 BO_Comma, BO->getType(), 4930 BO->getValueKind(), 4931 BO->getObjectKind(), 4932 BO->getOperatorLoc(), 4933 BO->isFPContractable())); 4934 } 4935 } 4936 4937 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E); 4938 if (TopBind) 4939 E = TopBind->getSubExpr(); 4940 4941 // Disable the special decltype handling now. 4942 ExprEvalContexts.back().IsDecltype = false; 4943 4944 // In MS mode, don't perform any extra checking of call return types within a 4945 // decltype expression. 4946 if (getLangOpts().MicrosoftMode) 4947 return Owned(E); 4948 4949 // Perform the semantic checks we delayed until this point. 4950 CallExpr *TopCall = dyn_cast<CallExpr>(E); 4951 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size(); 4952 I != N; ++I) { 4953 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I]; 4954 if (Call == TopCall) 4955 continue; 4956 4957 if (CheckCallReturnType(Call->getCallReturnType(), 4958 Call->getLocStart(), 4959 Call, Call->getDirectCallee())) 4960 return ExprError(); 4961 } 4962 4963 // Now all relevant types are complete, check the destructors are accessible 4964 // and non-deleted, and annotate them on the temporaries. 4965 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size(); 4966 I != N; ++I) { 4967 CXXBindTemporaryExpr *Bind = 4968 ExprEvalContexts.back().DelayedDecltypeBinds[I]; 4969 if (Bind == TopBind) 4970 continue; 4971 4972 CXXTemporary *Temp = Bind->getTemporary(); 4973 4974 CXXRecordDecl *RD = 4975 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 4976 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4977 Temp->setDestructor(Destructor); 4978 4979 MarkFunctionReferenced(Bind->getExprLoc(), Destructor); 4980 CheckDestructorAccess(Bind->getExprLoc(), Destructor, 4981 PDiag(diag::err_access_dtor_temp) 4982 << Bind->getType()); 4983 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc())) 4984 return ExprError(); 4985 4986 // We need a cleanup, but we don't need to remember the temporary. 4987 ExprNeedsCleanups = true; 4988 } 4989 4990 // Possibly strip off the top CXXBindTemporaryExpr. 4991 return Owned(E); 4992} 4993 4994ExprResult 4995Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4996 tok::TokenKind OpKind, ParsedType &ObjectType, 4997 bool &MayBePseudoDestructor) { 4998 // Since this might be a postfix expression, get rid of ParenListExprs. 4999 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 5000 if (Result.isInvalid()) return ExprError(); 5001 Base = Result.get(); 5002 5003 Result = CheckPlaceholderExpr(Base); 5004 if (Result.isInvalid()) return ExprError(); 5005 Base = Result.take(); 5006 5007 QualType BaseType = Base->getType(); 5008 MayBePseudoDestructor = false; 5009 if (BaseType->isDependentType()) { 5010 // If we have a pointer to a dependent type and are using the -> operator, 5011 // the object type is the type that the pointer points to. We might still 5012 // have enough information about that type to do something useful. 5013 if (OpKind == tok::arrow) 5014 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 5015 BaseType = Ptr->getPointeeType(); 5016 5017 ObjectType = ParsedType::make(BaseType); 5018 MayBePseudoDestructor = true; 5019 return Owned(Base); 5020 } 5021 5022 // C++ [over.match.oper]p8: 5023 // [...] When operator->returns, the operator-> is applied to the value 5024 // returned, with the original second operand. 5025 if (OpKind == tok::arrow) { 5026 // The set of types we've considered so far. 5027 llvm::SmallPtrSet<CanQualType,8> CTypes; 5028 SmallVector<SourceLocation, 8> Locations; 5029 CTypes.insert(Context.getCanonicalType(BaseType)); 5030 5031 while (BaseType->isRecordType()) { 5032 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 5033 if (Result.isInvalid()) 5034 return ExprError(); 5035 Base = Result.get(); 5036 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 5037 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 5038 BaseType = Base->getType(); 5039 CanQualType CBaseType = Context.getCanonicalType(BaseType); 5040 if (!CTypes.insert(CBaseType)) { 5041 Diag(OpLoc, diag::err_operator_arrow_circular); 5042 for (unsigned i = 0; i < Locations.size(); i++) 5043 Diag(Locations[i], diag::note_declared_at); 5044 return ExprError(); 5045 } 5046 } 5047 5048 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 5049 BaseType = BaseType->getPointeeType(); 5050 } 5051 5052 // Objective-C properties allow "." access on Objective-C pointer types, 5053 // so adjust the base type to the object type itself. 5054 if (BaseType->isObjCObjectPointerType()) 5055 BaseType = BaseType->getPointeeType(); 5056 5057 // C++ [basic.lookup.classref]p2: 5058 // [...] If the type of the object expression is of pointer to scalar 5059 // type, the unqualified-id is looked up in the context of the complete 5060 // postfix-expression. 5061 // 5062 // This also indicates that we could be parsing a pseudo-destructor-name. 5063 // Note that Objective-C class and object types can be pseudo-destructor 5064 // expressions or normal member (ivar or property) access expressions. 5065 if (BaseType->isObjCObjectOrInterfaceType()) { 5066 MayBePseudoDestructor = true; 5067 } else if (!BaseType->isRecordType()) { 5068 ObjectType = ParsedType(); 5069 MayBePseudoDestructor = true; 5070 return Owned(Base); 5071 } 5072 5073 // The object type must be complete (or dependent), or 5074 // C++11 [expr.prim.general]p3: 5075 // Unlike the object expression in other contexts, *this is not required to 5076 // be of complete type for purposes of class member access (5.2.5) outside 5077 // the member function body. 5078 if (!BaseType->isDependentType() && 5079 !isThisOutsideMemberFunctionBody(BaseType) && 5080 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access)) 5081 return ExprError(); 5082 5083 // C++ [basic.lookup.classref]p2: 5084 // If the id-expression in a class member access (5.2.5) is an 5085 // unqualified-id, and the type of the object expression is of a class 5086 // type C (or of pointer to a class type C), the unqualified-id is looked 5087 // up in the scope of class C. [...] 5088 ObjectType = ParsedType::make(BaseType); 5089 return Base; 5090} 5091 5092ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 5093 Expr *MemExpr) { 5094 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 5095 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 5096 << isa<CXXPseudoDestructorExpr>(MemExpr) 5097 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 5098 5099 return ActOnCallExpr(/*Scope*/ 0, 5100 MemExpr, 5101 /*LPLoc*/ ExpectedLParenLoc, 5102 None, 5103 /*RPLoc*/ ExpectedLParenLoc); 5104} 5105 5106static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 5107 tok::TokenKind& OpKind, SourceLocation OpLoc) { 5108 if (Base->hasPlaceholderType()) { 5109 ExprResult result = S.CheckPlaceholderExpr(Base); 5110 if (result.isInvalid()) return true; 5111 Base = result.take(); 5112 } 5113 ObjectType = Base->getType(); 5114 5115 // C++ [expr.pseudo]p2: 5116 // The left-hand side of the dot operator shall be of scalar type. The 5117 // left-hand side of the arrow operator shall be of pointer to scalar type. 5118 // This scalar type is the object type. 5119 // Note that this is rather different from the normal handling for the 5120 // arrow operator. 5121 if (OpKind == tok::arrow) { 5122 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 5123 ObjectType = Ptr->getPointeeType(); 5124 } else if (!Base->isTypeDependent()) { 5125 // The user wrote "p->" when she probably meant "p."; fix it. 5126 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 5127 << ObjectType << true 5128 << FixItHint::CreateReplacement(OpLoc, "."); 5129 if (S.isSFINAEContext()) 5130 return true; 5131 5132 OpKind = tok::period; 5133 } 5134 } 5135 5136 return false; 5137} 5138 5139ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 5140 SourceLocation OpLoc, 5141 tok::TokenKind OpKind, 5142 const CXXScopeSpec &SS, 5143 TypeSourceInfo *ScopeTypeInfo, 5144 SourceLocation CCLoc, 5145 SourceLocation TildeLoc, 5146 PseudoDestructorTypeStorage Destructed, 5147 bool HasTrailingLParen) { 5148 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 5149 5150 QualType ObjectType; 5151 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5152 return ExprError(); 5153 5154 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() && 5155 !ObjectType->isVectorType()) { 5156 if (getLangOpts().MicrosoftMode && ObjectType->isVoidType()) 5157 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 5158 else 5159 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 5160 << ObjectType << Base->getSourceRange(); 5161 return ExprError(); 5162 } 5163 5164 // C++ [expr.pseudo]p2: 5165 // [...] The cv-unqualified versions of the object type and of the type 5166 // designated by the pseudo-destructor-name shall be the same type. 5167 if (DestructedTypeInfo) { 5168 QualType DestructedType = DestructedTypeInfo->getType(); 5169 SourceLocation DestructedTypeStart 5170 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 5171 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 5172 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 5173 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 5174 << ObjectType << DestructedType << Base->getSourceRange() 5175 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5176 5177 // Recover by setting the destructed type to the object type. 5178 DestructedType = ObjectType; 5179 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5180 DestructedTypeStart); 5181 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5182 } else if (DestructedType.getObjCLifetime() != 5183 ObjectType.getObjCLifetime()) { 5184 5185 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 5186 // Okay: just pretend that the user provided the correctly-qualified 5187 // type. 5188 } else { 5189 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 5190 << ObjectType << DestructedType << Base->getSourceRange() 5191 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5192 } 5193 5194 // Recover by setting the destructed type to the object type. 5195 DestructedType = ObjectType; 5196 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5197 DestructedTypeStart); 5198 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5199 } 5200 } 5201 } 5202 5203 // C++ [expr.pseudo]p2: 5204 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 5205 // form 5206 // 5207 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 5208 // 5209 // shall designate the same scalar type. 5210 if (ScopeTypeInfo) { 5211 QualType ScopeType = ScopeTypeInfo->getType(); 5212 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 5213 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 5214 5215 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 5216 diag::err_pseudo_dtor_type_mismatch) 5217 << ObjectType << ScopeType << Base->getSourceRange() 5218 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 5219 5220 ScopeType = QualType(); 5221 ScopeTypeInfo = 0; 5222 } 5223 } 5224 5225 Expr *Result 5226 = new (Context) CXXPseudoDestructorExpr(Context, Base, 5227 OpKind == tok::arrow, OpLoc, 5228 SS.getWithLocInContext(Context), 5229 ScopeTypeInfo, 5230 CCLoc, 5231 TildeLoc, 5232 Destructed); 5233 5234 if (HasTrailingLParen) 5235 return Owned(Result); 5236 5237 return DiagnoseDtorReference(Destructed.getLocation(), Result); 5238} 5239 5240ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5241 SourceLocation OpLoc, 5242 tok::TokenKind OpKind, 5243 CXXScopeSpec &SS, 5244 UnqualifiedId &FirstTypeName, 5245 SourceLocation CCLoc, 5246 SourceLocation TildeLoc, 5247 UnqualifiedId &SecondTypeName, 5248 bool HasTrailingLParen) { 5249 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5250 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5251 "Invalid first type name in pseudo-destructor"); 5252 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5253 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5254 "Invalid second type name in pseudo-destructor"); 5255 5256 QualType ObjectType; 5257 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5258 return ExprError(); 5259 5260 // Compute the object type that we should use for name lookup purposes. Only 5261 // record types and dependent types matter. 5262 ParsedType ObjectTypePtrForLookup; 5263 if (!SS.isSet()) { 5264 if (ObjectType->isRecordType()) 5265 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 5266 else if (ObjectType->isDependentType()) 5267 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 5268 } 5269 5270 // Convert the name of the type being destructed (following the ~) into a 5271 // type (with source-location information). 5272 QualType DestructedType; 5273 TypeSourceInfo *DestructedTypeInfo = 0; 5274 PseudoDestructorTypeStorage Destructed; 5275 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5276 ParsedType T = getTypeName(*SecondTypeName.Identifier, 5277 SecondTypeName.StartLocation, 5278 S, &SS, true, false, ObjectTypePtrForLookup); 5279 if (!T && 5280 ((SS.isSet() && !computeDeclContext(SS, false)) || 5281 (!SS.isSet() && ObjectType->isDependentType()))) { 5282 // The name of the type being destroyed is a dependent name, and we 5283 // couldn't find anything useful in scope. Just store the identifier and 5284 // it's location, and we'll perform (qualified) name lookup again at 5285 // template instantiation time. 5286 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 5287 SecondTypeName.StartLocation); 5288 } else if (!T) { 5289 Diag(SecondTypeName.StartLocation, 5290 diag::err_pseudo_dtor_destructor_non_type) 5291 << SecondTypeName.Identifier << ObjectType; 5292 if (isSFINAEContext()) 5293 return ExprError(); 5294 5295 // Recover by assuming we had the right type all along. 5296 DestructedType = ObjectType; 5297 } else 5298 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 5299 } else { 5300 // Resolve the template-id to a type. 5301 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 5302 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5303 TemplateId->NumArgs); 5304 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5305 TemplateId->TemplateKWLoc, 5306 TemplateId->Template, 5307 TemplateId->TemplateNameLoc, 5308 TemplateId->LAngleLoc, 5309 TemplateArgsPtr, 5310 TemplateId->RAngleLoc); 5311 if (T.isInvalid() || !T.get()) { 5312 // Recover by assuming we had the right type all along. 5313 DestructedType = ObjectType; 5314 } else 5315 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 5316 } 5317 5318 // If we've performed some kind of recovery, (re-)build the type source 5319 // information. 5320 if (!DestructedType.isNull()) { 5321 if (!DestructedTypeInfo) 5322 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 5323 SecondTypeName.StartLocation); 5324 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5325 } 5326 5327 // Convert the name of the scope type (the type prior to '::') into a type. 5328 TypeSourceInfo *ScopeTypeInfo = 0; 5329 QualType ScopeType; 5330 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5331 FirstTypeName.Identifier) { 5332 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5333 ParsedType T = getTypeName(*FirstTypeName.Identifier, 5334 FirstTypeName.StartLocation, 5335 S, &SS, true, false, ObjectTypePtrForLookup); 5336 if (!T) { 5337 Diag(FirstTypeName.StartLocation, 5338 diag::err_pseudo_dtor_destructor_non_type) 5339 << FirstTypeName.Identifier << ObjectType; 5340 5341 if (isSFINAEContext()) 5342 return ExprError(); 5343 5344 // Just drop this type. It's unnecessary anyway. 5345 ScopeType = QualType(); 5346 } else 5347 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 5348 } else { 5349 // Resolve the template-id to a type. 5350 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 5351 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5352 TemplateId->NumArgs); 5353 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5354 TemplateId->TemplateKWLoc, 5355 TemplateId->Template, 5356 TemplateId->TemplateNameLoc, 5357 TemplateId->LAngleLoc, 5358 TemplateArgsPtr, 5359 TemplateId->RAngleLoc); 5360 if (T.isInvalid() || !T.get()) { 5361 // Recover by dropping this type. 5362 ScopeType = QualType(); 5363 } else 5364 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 5365 } 5366 } 5367 5368 if (!ScopeType.isNull() && !ScopeTypeInfo) 5369 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 5370 FirstTypeName.StartLocation); 5371 5372 5373 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 5374 ScopeTypeInfo, CCLoc, TildeLoc, 5375 Destructed, HasTrailingLParen); 5376} 5377 5378ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5379 SourceLocation OpLoc, 5380 tok::TokenKind OpKind, 5381 SourceLocation TildeLoc, 5382 const DeclSpec& DS, 5383 bool HasTrailingLParen) { 5384 QualType ObjectType; 5385 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5386 return ExprError(); 5387 5388 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 5389 5390 TypeLocBuilder TLB; 5391 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 5392 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 5393 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 5394 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 5395 5396 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 5397 0, SourceLocation(), TildeLoc, 5398 Destructed, HasTrailingLParen); 5399} 5400 5401ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 5402 CXXConversionDecl *Method, 5403 bool HadMultipleCandidates) { 5404 if (Method->getParent()->isLambda() && 5405 Method->getConversionType()->isBlockPointerType()) { 5406 // This is a lambda coversion to block pointer; check if the argument 5407 // is a LambdaExpr. 5408 Expr *SubE = E; 5409 CastExpr *CE = dyn_cast<CastExpr>(SubE); 5410 if (CE && CE->getCastKind() == CK_NoOp) 5411 SubE = CE->getSubExpr(); 5412 SubE = SubE->IgnoreParens(); 5413 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE)) 5414 SubE = BE->getSubExpr(); 5415 if (isa<LambdaExpr>(SubE)) { 5416 // For the conversion to block pointer on a lambda expression, we 5417 // construct a special BlockLiteral instead; this doesn't really make 5418 // a difference in ARC, but outside of ARC the resulting block literal 5419 // follows the normal lifetime rules for block literals instead of being 5420 // autoreleased. 5421 DiagnosticErrorTrap Trap(Diags); 5422 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(), 5423 E->getExprLoc(), 5424 Method, E); 5425 if (Exp.isInvalid()) 5426 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv); 5427 return Exp; 5428 } 5429 } 5430 5431 5432 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 5433 FoundDecl, Method); 5434 if (Exp.isInvalid()) 5435 return true; 5436 5437 MemberExpr *ME = 5438 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 5439 SourceLocation(), Context.BoundMemberTy, 5440 VK_RValue, OK_Ordinary); 5441 if (HadMultipleCandidates) 5442 ME->setHadMultipleCandidates(true); 5443 MarkMemberReferenced(ME); 5444 5445 QualType ResultType = Method->getResultType(); 5446 ExprValueKind VK = Expr::getValueKindForType(ResultType); 5447 ResultType = ResultType.getNonLValueExprType(Context); 5448 5449 CXXMemberCallExpr *CE = 5450 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK, 5451 Exp.get()->getLocEnd()); 5452 return CE; 5453} 5454 5455ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 5456 SourceLocation RParen) { 5457 CanThrowResult CanThrow = canThrow(Operand); 5458 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 5459 CanThrow, KeyLoc, RParen)); 5460} 5461 5462ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 5463 Expr *Operand, SourceLocation RParen) { 5464 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 5465} 5466 5467static bool IsSpecialDiscardedValue(Expr *E) { 5468 // In C++11, discarded-value expressions of a certain form are special, 5469 // according to [expr]p10: 5470 // The lvalue-to-rvalue conversion (4.1) is applied only if the 5471 // expression is an lvalue of volatile-qualified type and it has 5472 // one of the following forms: 5473 E = E->IgnoreParens(); 5474 5475 // - id-expression (5.1.1), 5476 if (isa<DeclRefExpr>(E)) 5477 return true; 5478 5479 // - subscripting (5.2.1), 5480 if (isa<ArraySubscriptExpr>(E)) 5481 return true; 5482 5483 // - class member access (5.2.5), 5484 if (isa<MemberExpr>(E)) 5485 return true; 5486 5487 // - indirection (5.3.1), 5488 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) 5489 if (UO->getOpcode() == UO_Deref) 5490 return true; 5491 5492 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 5493 // - pointer-to-member operation (5.5), 5494 if (BO->isPtrMemOp()) 5495 return true; 5496 5497 // - comma expression (5.18) where the right operand is one of the above. 5498 if (BO->getOpcode() == BO_Comma) 5499 return IsSpecialDiscardedValue(BO->getRHS()); 5500 } 5501 5502 // - conditional expression (5.16) where both the second and the third 5503 // operands are one of the above, or 5504 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) 5505 return IsSpecialDiscardedValue(CO->getTrueExpr()) && 5506 IsSpecialDiscardedValue(CO->getFalseExpr()); 5507 // The related edge case of "*x ?: *x". 5508 if (BinaryConditionalOperator *BCO = 5509 dyn_cast<BinaryConditionalOperator>(E)) { 5510 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr())) 5511 return IsSpecialDiscardedValue(OVE->getSourceExpr()) && 5512 IsSpecialDiscardedValue(BCO->getFalseExpr()); 5513 } 5514 5515 // Objective-C++ extensions to the rule. 5516 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E)) 5517 return true; 5518 5519 return false; 5520} 5521 5522/// Perform the conversions required for an expression used in a 5523/// context that ignores the result. 5524ExprResult Sema::IgnoredValueConversions(Expr *E) { 5525 if (E->hasPlaceholderType()) { 5526 ExprResult result = CheckPlaceholderExpr(E); 5527 if (result.isInvalid()) return Owned(E); 5528 E = result.take(); 5529 } 5530 5531 // C99 6.3.2.1: 5532 // [Except in specific positions,] an lvalue that does not have 5533 // array type is converted to the value stored in the 5534 // designated object (and is no longer an lvalue). 5535 if (E->isRValue()) { 5536 // In C, function designators (i.e. expressions of function type) 5537 // are r-values, but we still want to do function-to-pointer decay 5538 // on them. This is both technically correct and convenient for 5539 // some clients. 5540 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType()) 5541 return DefaultFunctionArrayConversion(E); 5542 5543 return Owned(E); 5544 } 5545 5546 if (getLangOpts().CPlusPlus) { 5547 // The C++11 standard defines the notion of a discarded-value expression; 5548 // normally, we don't need to do anything to handle it, but if it is a 5549 // volatile lvalue with a special form, we perform an lvalue-to-rvalue 5550 // conversion. 5551 if (getLangOpts().CPlusPlus11 && E->isGLValue() && 5552 E->getType().isVolatileQualified() && 5553 IsSpecialDiscardedValue(E)) { 5554 ExprResult Res = DefaultLvalueConversion(E); 5555 if (Res.isInvalid()) 5556 return Owned(E); 5557 E = Res.take(); 5558 } 5559 return Owned(E); 5560 } 5561 5562 // GCC seems to also exclude expressions of incomplete enum type. 5563 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 5564 if (!T->getDecl()->isComplete()) { 5565 // FIXME: stupid workaround for a codegen bug! 5566 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 5567 return Owned(E); 5568 } 5569 } 5570 5571 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 5572 if (Res.isInvalid()) 5573 return Owned(E); 5574 E = Res.take(); 5575 5576 if (!E->getType()->isVoidType()) 5577 RequireCompleteType(E->getExprLoc(), E->getType(), 5578 diag::err_incomplete_type); 5579 return Owned(E); 5580} 5581 5582ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC, 5583 bool DiscardedValue, 5584 bool IsConstexpr) { 5585 ExprResult FullExpr = Owned(FE); 5586 5587 if (!FullExpr.get()) 5588 return ExprError(); 5589 5590 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 5591 return ExprError(); 5592 5593 // Top-level expressions default to 'id' when we're in a debugger. 5594 if (DiscardedValue && getLangOpts().DebuggerCastResultToId && 5595 FullExpr.get()->getType() == Context.UnknownAnyTy) { 5596 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 5597 if (FullExpr.isInvalid()) 5598 return ExprError(); 5599 } 5600 5601 if (DiscardedValue) { 5602 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 5603 if (FullExpr.isInvalid()) 5604 return ExprError(); 5605 5606 FullExpr = IgnoredValueConversions(FullExpr.take()); 5607 if (FullExpr.isInvalid()) 5608 return ExprError(); 5609 } 5610 5611 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr); 5612 return MaybeCreateExprWithCleanups(FullExpr); 5613} 5614 5615StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 5616 if (!FullStmt) return StmtError(); 5617 5618 return MaybeCreateStmtWithCleanups(FullStmt); 5619} 5620 5621Sema::IfExistsResult 5622Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 5623 CXXScopeSpec &SS, 5624 const DeclarationNameInfo &TargetNameInfo) { 5625 DeclarationName TargetName = TargetNameInfo.getName(); 5626 if (!TargetName) 5627 return IER_DoesNotExist; 5628 5629 // If the name itself is dependent, then the result is dependent. 5630 if (TargetName.isDependentName()) 5631 return IER_Dependent; 5632 5633 // Do the redeclaration lookup in the current scope. 5634 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 5635 Sema::NotForRedeclaration); 5636 LookupParsedName(R, S, &SS); 5637 R.suppressDiagnostics(); 5638 5639 switch (R.getResultKind()) { 5640 case LookupResult::Found: 5641 case LookupResult::FoundOverloaded: 5642 case LookupResult::FoundUnresolvedValue: 5643 case LookupResult::Ambiguous: 5644 return IER_Exists; 5645 5646 case LookupResult::NotFound: 5647 return IER_DoesNotExist; 5648 5649 case LookupResult::NotFoundInCurrentInstantiation: 5650 return IER_Dependent; 5651 } 5652 5653 llvm_unreachable("Invalid LookupResult Kind!"); 5654} 5655 5656Sema::IfExistsResult 5657Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 5658 bool IsIfExists, CXXScopeSpec &SS, 5659 UnqualifiedId &Name) { 5660 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 5661 5662 // Check for unexpanded parameter packs. 5663 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 5664 collectUnexpandedParameterPacks(SS, Unexpanded); 5665 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 5666 if (!Unexpanded.empty()) { 5667 DiagnoseUnexpandedParameterPacks(KeywordLoc, 5668 IsIfExists? UPPC_IfExists 5669 : UPPC_IfNotExists, 5670 Unexpanded); 5671 return IER_Error; 5672 } 5673 5674 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 5675} 5676