SemaExprCXX.cpp revision 8e6b7093c840ddd4054523333b5a0d3262c3c2c2
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, 1338 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs), 1339 AllPlaceArgs, CallType)) 1340 return ExprError(); 1341 1342 NumPlaceArgs = AllPlaceArgs.size(); 1343 if (NumPlaceArgs > 0) 1344 PlaceArgs = &AllPlaceArgs[0]; 1345 1346 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, 1347 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs)); 1348 1349 // FIXME: Missing call to CheckFunctionCall or equivalent 1350 } 1351 1352 // Warn if the type is over-aligned and is being allocated by global operator 1353 // new. 1354 if (NumPlaceArgs == 0 && OperatorNew && 1355 (OperatorNew->isImplicit() || 1356 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1357 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1358 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1359 if (Align > SuitableAlign) 1360 Diag(StartLoc, diag::warn_overaligned_type) 1361 << AllocType 1362 << unsigned(Align / Context.getCharWidth()) 1363 << unsigned(SuitableAlign / Context.getCharWidth()); 1364 } 1365 } 1366 1367 QualType InitType = AllocType; 1368 // Array 'new' can't have any initializers except empty parentheses. 1369 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1370 // dialect distinction. 1371 if (ResultType->isArrayType() || ArraySize) { 1372 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1373 SourceRange InitRange(Inits[0]->getLocStart(), 1374 Inits[NumInits - 1]->getLocEnd()); 1375 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1376 return ExprError(); 1377 } 1378 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1379 // We do the initialization typechecking against the array type 1380 // corresponding to the number of initializers + 1 (to also check 1381 // default-initialization). 1382 unsigned NumElements = ILE->getNumInits() + 1; 1383 InitType = Context.getConstantArrayType(AllocType, 1384 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1385 ArrayType::Normal, 0); 1386 } 1387 } 1388 1389 // If we can perform the initialization, and we've not already done so, 1390 // do it now. 1391 if (!AllocType->isDependentType() && 1392 !Expr::hasAnyTypeDependentArguments( 1393 llvm::makeArrayRef(Inits, NumInits)) && 1394 !HaveCompleteInit) { 1395 // C++11 [expr.new]p15: 1396 // A new-expression that creates an object of type T initializes that 1397 // object as follows: 1398 InitializationKind Kind 1399 // - If the new-initializer is omitted, the object is default- 1400 // initialized (8.5); if no initialization is performed, 1401 // the object has indeterminate value 1402 = initStyle == CXXNewExpr::NoInit 1403 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1404 // - Otherwise, the new-initializer is interpreted according to the 1405 // initialization rules of 8.5 for direct-initialization. 1406 : initStyle == CXXNewExpr::ListInit 1407 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1408 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1409 DirectInitRange.getBegin(), 1410 DirectInitRange.getEnd()); 1411 1412 InitializedEntity Entity 1413 = InitializedEntity::InitializeNew(StartLoc, InitType); 1414 InitializationSequence InitSeq(*this, Entity, Kind, MultiExprArg(Inits, NumInits)); 1415 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1416 MultiExprArg(Inits, NumInits)); 1417 if (FullInit.isInvalid()) 1418 return ExprError(); 1419 1420 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1421 // we don't want the initialized object to be destructed. 1422 if (CXXBindTemporaryExpr *Binder = 1423 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1424 FullInit = Owned(Binder->getSubExpr()); 1425 1426 Initializer = FullInit.take(); 1427 } 1428 1429 // Mark the new and delete operators as referenced. 1430 if (OperatorNew) { 1431 if (DiagnoseUseOfDecl(OperatorNew, StartLoc)) 1432 return ExprError(); 1433 MarkFunctionReferenced(StartLoc, OperatorNew); 1434 } 1435 if (OperatorDelete) { 1436 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc)) 1437 return ExprError(); 1438 MarkFunctionReferenced(StartLoc, OperatorDelete); 1439 } 1440 1441 // C++0x [expr.new]p17: 1442 // If the new expression creates an array of objects of class type, 1443 // access and ambiguity control are done for the destructor. 1444 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1445 if (ArraySize && !BaseAllocType->isDependentType()) { 1446 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) { 1447 if (CXXDestructorDecl *dtor = LookupDestructor( 1448 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) { 1449 MarkFunctionReferenced(StartLoc, dtor); 1450 CheckDestructorAccess(StartLoc, dtor, 1451 PDiag(diag::err_access_dtor) 1452 << BaseAllocType); 1453 if (DiagnoseUseOfDecl(dtor, StartLoc)) 1454 return ExprError(); 1455 } 1456 } 1457 } 1458 1459 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1460 OperatorDelete, 1461 UsualArrayDeleteWantsSize, 1462 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs), 1463 TypeIdParens, 1464 ArraySize, initStyle, Initializer, 1465 ResultType, AllocTypeInfo, 1466 Range, DirectInitRange)); 1467} 1468 1469/// \brief Checks that a type is suitable as the allocated type 1470/// in a new-expression. 1471bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1472 SourceRange R) { 1473 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1474 // abstract class type or array thereof. 1475 if (AllocType->isFunctionType()) 1476 return Diag(Loc, diag::err_bad_new_type) 1477 << AllocType << 0 << R; 1478 else if (AllocType->isReferenceType()) 1479 return Diag(Loc, diag::err_bad_new_type) 1480 << AllocType << 1 << R; 1481 else if (!AllocType->isDependentType() && 1482 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R)) 1483 return true; 1484 else if (RequireNonAbstractType(Loc, AllocType, 1485 diag::err_allocation_of_abstract_type)) 1486 return true; 1487 else if (AllocType->isVariablyModifiedType()) 1488 return Diag(Loc, diag::err_variably_modified_new_type) 1489 << AllocType; 1490 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1491 return Diag(Loc, diag::err_address_space_qualified_new) 1492 << AllocType.getUnqualifiedType() << AddressSpace; 1493 else if (getLangOpts().ObjCAutoRefCount) { 1494 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1495 QualType BaseAllocType = Context.getBaseElementType(AT); 1496 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1497 BaseAllocType->isObjCLifetimeType()) 1498 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1499 << BaseAllocType; 1500 } 1501 } 1502 1503 return false; 1504} 1505 1506/// \brief Determine whether the given function is a non-placement 1507/// deallocation function. 1508static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1509 if (FD->isInvalidDecl()) 1510 return false; 1511 1512 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1513 return Method->isUsualDeallocationFunction(); 1514 1515 return ((FD->getOverloadedOperator() == OO_Delete || 1516 FD->getOverloadedOperator() == OO_Array_Delete) && 1517 FD->getNumParams() == 1); 1518} 1519 1520/// FindAllocationFunctions - Finds the overloads of operator new and delete 1521/// that are appropriate for the allocation. 1522bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1523 bool UseGlobal, QualType AllocType, 1524 bool IsArray, Expr **PlaceArgs, 1525 unsigned NumPlaceArgs, 1526 FunctionDecl *&OperatorNew, 1527 FunctionDecl *&OperatorDelete) { 1528 // --- Choosing an allocation function --- 1529 // C++ 5.3.4p8 - 14 & 18 1530 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1531 // in the scope of the allocated class. 1532 // 2) If an array size is given, look for operator new[], else look for 1533 // operator new. 1534 // 3) The first argument is always size_t. Append the arguments from the 1535 // placement form. 1536 1537 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1538 // We don't care about the actual value of this argument. 1539 // FIXME: Should the Sema create the expression and embed it in the syntax 1540 // tree? Or should the consumer just recalculate the value? 1541 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1542 Context.getTargetInfo().getPointerWidth(0)), 1543 Context.getSizeType(), 1544 SourceLocation()); 1545 AllocArgs[0] = &Size; 1546 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1547 1548 // C++ [expr.new]p8: 1549 // If the allocated type is a non-array type, the allocation 1550 // function's name is operator new and the deallocation function's 1551 // name is operator delete. If the allocated type is an array 1552 // type, the allocation function's name is operator new[] and the 1553 // deallocation function's name is operator delete[]. 1554 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1555 IsArray ? OO_Array_New : OO_New); 1556 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1557 IsArray ? OO_Array_Delete : OO_Delete); 1558 1559 QualType AllocElemType = Context.getBaseElementType(AllocType); 1560 1561 if (AllocElemType->isRecordType() && !UseGlobal) { 1562 CXXRecordDecl *Record 1563 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1564 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, Record, 1565 /*AllowMissing=*/true, 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, TUDecl, 1573 /*AllowMissing=*/false, OperatorNew)) 1574 return true; 1575 } 1576 1577 // We don't need an operator delete if we're running under 1578 // -fno-exceptions. 1579 if (!getLangOpts().Exceptions) { 1580 OperatorDelete = 0; 1581 return false; 1582 } 1583 1584 // FindAllocationOverload can change the passed in arguments, so we need to 1585 // copy them back. 1586 if (NumPlaceArgs > 0) 1587 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1588 1589 // C++ [expr.new]p19: 1590 // 1591 // If the new-expression begins with a unary :: operator, the 1592 // deallocation function's name is looked up in the global 1593 // scope. Otherwise, if the allocated type is a class type T or an 1594 // array thereof, the deallocation function's name is looked up in 1595 // the scope of T. If this lookup fails to find the name, or if 1596 // the allocated type is not a class type or array thereof, the 1597 // deallocation function's name is looked up in the global scope. 1598 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1599 if (AllocElemType->isRecordType() && !UseGlobal) { 1600 CXXRecordDecl *RD 1601 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1602 LookupQualifiedName(FoundDelete, RD); 1603 } 1604 if (FoundDelete.isAmbiguous()) 1605 return true; // FIXME: clean up expressions? 1606 1607 if (FoundDelete.empty()) { 1608 DeclareGlobalNewDelete(); 1609 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1610 } 1611 1612 FoundDelete.suppressDiagnostics(); 1613 1614 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1615 1616 // Whether we're looking for a placement operator delete is dictated 1617 // by whether we selected a placement operator new, not by whether 1618 // we had explicit placement arguments. This matters for things like 1619 // struct A { void *operator new(size_t, int = 0); ... }; 1620 // A *a = new A() 1621 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1622 1623 if (isPlacementNew) { 1624 // C++ [expr.new]p20: 1625 // A declaration of a placement deallocation function matches the 1626 // declaration of a placement allocation function if it has the 1627 // same number of parameters and, after parameter transformations 1628 // (8.3.5), all parameter types except the first are 1629 // identical. [...] 1630 // 1631 // To perform this comparison, we compute the function type that 1632 // the deallocation function should have, and use that type both 1633 // for template argument deduction and for comparison purposes. 1634 // 1635 // FIXME: this comparison should ignore CC and the like. 1636 QualType ExpectedFunctionType; 1637 { 1638 const FunctionProtoType *Proto 1639 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1640 1641 SmallVector<QualType, 4> ArgTypes; 1642 ArgTypes.push_back(Context.VoidPtrTy); 1643 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1644 ArgTypes.push_back(Proto->getArgType(I)); 1645 1646 FunctionProtoType::ExtProtoInfo EPI; 1647 EPI.Variadic = Proto->isVariadic(); 1648 1649 ExpectedFunctionType 1650 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI); 1651 } 1652 1653 for (LookupResult::iterator D = FoundDelete.begin(), 1654 DEnd = FoundDelete.end(); 1655 D != DEnd; ++D) { 1656 FunctionDecl *Fn = 0; 1657 if (FunctionTemplateDecl *FnTmpl 1658 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1659 // Perform template argument deduction to try to match the 1660 // expected function type. 1661 TemplateDeductionInfo Info(StartLoc); 1662 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1663 continue; 1664 } else 1665 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1666 1667 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1668 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1669 } 1670 } else { 1671 // C++ [expr.new]p20: 1672 // [...] Any non-placement deallocation function matches a 1673 // non-placement allocation function. [...] 1674 for (LookupResult::iterator D = FoundDelete.begin(), 1675 DEnd = FoundDelete.end(); 1676 D != DEnd; ++D) { 1677 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1678 if (isNonPlacementDeallocationFunction(Fn)) 1679 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1680 } 1681 } 1682 1683 // C++ [expr.new]p20: 1684 // [...] If the lookup finds a single matching deallocation 1685 // function, that function will be called; otherwise, no 1686 // deallocation function will be called. 1687 if (Matches.size() == 1) { 1688 OperatorDelete = Matches[0].second; 1689 1690 // C++0x [expr.new]p20: 1691 // If the lookup finds the two-parameter form of a usual 1692 // deallocation function (3.7.4.2) and that function, considered 1693 // as a placement deallocation function, would have been 1694 // selected as a match for the allocation function, the program 1695 // is ill-formed. 1696 if (NumPlaceArgs && getLangOpts().CPlusPlus11 && 1697 isNonPlacementDeallocationFunction(OperatorDelete)) { 1698 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1699 << SourceRange(PlaceArgs[0]->getLocStart(), 1700 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1701 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1702 << DeleteName; 1703 } else { 1704 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1705 Matches[0].first); 1706 } 1707 } 1708 1709 return false; 1710} 1711 1712/// FindAllocationOverload - Find an fitting overload for the allocation 1713/// function in the specified scope. 1714bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1715 DeclarationName Name, MultiExprArg Args, 1716 DeclContext *Ctx, 1717 bool AllowMissing, FunctionDecl *&Operator, 1718 bool Diagnose) { 1719 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1720 LookupQualifiedName(R, Ctx); 1721 if (R.empty()) { 1722 if (AllowMissing || !Diagnose) 1723 return false; 1724 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1725 << Name << Range; 1726 } 1727 1728 if (R.isAmbiguous()) 1729 return true; 1730 1731 R.suppressDiagnostics(); 1732 1733 OverloadCandidateSet Candidates(StartLoc); 1734 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1735 Alloc != AllocEnd; ++Alloc) { 1736 // Even member operator new/delete are implicitly treated as 1737 // static, so don't use AddMemberCandidate. 1738 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1739 1740 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1741 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1742 /*ExplicitTemplateArgs=*/0, 1743 Args, Candidates, 1744 /*SuppressUserConversions=*/false); 1745 continue; 1746 } 1747 1748 FunctionDecl *Fn = cast<FunctionDecl>(D); 1749 AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates, 1750 /*SuppressUserConversions=*/false); 1751 } 1752 1753 // Do the resolution. 1754 OverloadCandidateSet::iterator Best; 1755 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1756 case OR_Success: { 1757 // Got one! 1758 FunctionDecl *FnDecl = Best->Function; 1759 MarkFunctionReferenced(StartLoc, FnDecl); 1760 // The first argument is size_t, and the first parameter must be size_t, 1761 // too. This is checked on declaration and can be assumed. (It can't be 1762 // asserted on, though, since invalid decls are left in there.) 1763 // Watch out for variadic allocator function. 1764 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1765 for (unsigned i = 0; (i < Args.size() && i < NumArgsInFnDecl); ++i) { 1766 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1767 FnDecl->getParamDecl(i)); 1768 1769 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1770 return true; 1771 1772 ExprResult Result 1773 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1774 if (Result.isInvalid()) 1775 return true; 1776 1777 Args[i] = Result.takeAs<Expr>(); 1778 } 1779 1780 Operator = FnDecl; 1781 1782 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), 1783 Best->FoundDecl, Diagnose) == AR_inaccessible) 1784 return true; 1785 1786 return false; 1787 } 1788 1789 case OR_No_Viable_Function: 1790 if (Diagnose) { 1791 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1792 << Name << Range; 1793 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args); 1794 } 1795 return true; 1796 1797 case OR_Ambiguous: 1798 if (Diagnose) { 1799 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1800 << Name << Range; 1801 Candidates.NoteCandidates(*this, OCD_ViableCandidates, Args); 1802 } 1803 return true; 1804 1805 case OR_Deleted: { 1806 if (Diagnose) { 1807 Diag(StartLoc, diag::err_ovl_deleted_call) 1808 << Best->Function->isDeleted() 1809 << Name 1810 << getDeletedOrUnavailableSuffix(Best->Function) 1811 << Range; 1812 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args); 1813 } 1814 return true; 1815 } 1816 } 1817 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1818} 1819 1820 1821/// DeclareGlobalNewDelete - Declare the global forms of operator new and 1822/// delete. These are: 1823/// @code 1824/// // C++03: 1825/// void* operator new(std::size_t) throw(std::bad_alloc); 1826/// void* operator new[](std::size_t) throw(std::bad_alloc); 1827/// void operator delete(void *) throw(); 1828/// void operator delete[](void *) throw(); 1829/// // C++0x: 1830/// void* operator new(std::size_t); 1831/// void* operator new[](std::size_t); 1832/// void operator delete(void *); 1833/// void operator delete[](void *); 1834/// @endcode 1835/// C++0x operator delete is implicitly noexcept. 1836/// Note that the placement and nothrow forms of new are *not* implicitly 1837/// declared. Their use requires including \<new\>. 1838void Sema::DeclareGlobalNewDelete() { 1839 if (GlobalNewDeleteDeclared) 1840 return; 1841 1842 // C++ [basic.std.dynamic]p2: 1843 // [...] The following allocation and deallocation functions (18.4) are 1844 // implicitly declared in global scope in each translation unit of a 1845 // program 1846 // 1847 // C++03: 1848 // void* operator new(std::size_t) throw(std::bad_alloc); 1849 // void* operator new[](std::size_t) throw(std::bad_alloc); 1850 // void operator delete(void*) throw(); 1851 // void operator delete[](void*) throw(); 1852 // C++0x: 1853 // void* operator new(std::size_t); 1854 // void* operator new[](std::size_t); 1855 // void operator delete(void*); 1856 // void operator delete[](void*); 1857 // 1858 // These implicit declarations introduce only the function names operator 1859 // new, operator new[], operator delete, operator delete[]. 1860 // 1861 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1862 // "std" or "bad_alloc" as necessary to form the exception specification. 1863 // However, we do not make these implicit declarations visible to name 1864 // lookup. 1865 // Note that the C++0x versions of operator delete are deallocation functions, 1866 // and thus are implicitly noexcept. 1867 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) { 1868 // The "std::bad_alloc" class has not yet been declared, so build it 1869 // implicitly. 1870 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1871 getOrCreateStdNamespace(), 1872 SourceLocation(), SourceLocation(), 1873 &PP.getIdentifierTable().get("bad_alloc"), 1874 0); 1875 getStdBadAlloc()->setImplicit(true); 1876 } 1877 1878 GlobalNewDeleteDeclared = true; 1879 1880 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1881 QualType SizeT = Context.getSizeType(); 1882 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew; 1883 1884 DeclareGlobalAllocationFunction( 1885 Context.DeclarationNames.getCXXOperatorName(OO_New), 1886 VoidPtr, SizeT, AssumeSaneOperatorNew); 1887 DeclareGlobalAllocationFunction( 1888 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1889 VoidPtr, SizeT, AssumeSaneOperatorNew); 1890 DeclareGlobalAllocationFunction( 1891 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1892 Context.VoidTy, VoidPtr); 1893 DeclareGlobalAllocationFunction( 1894 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1895 Context.VoidTy, VoidPtr); 1896} 1897 1898/// DeclareGlobalAllocationFunction - Declares a single implicit global 1899/// allocation function if it doesn't already exist. 1900void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1901 QualType Return, QualType Argument, 1902 bool AddMallocAttr) { 1903 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1904 1905 // Check if this function is already declared. 1906 { 1907 DeclContext::lookup_result R = GlobalCtx->lookup(Name); 1908 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end(); 1909 Alloc != AllocEnd; ++Alloc) { 1910 // Only look at non-template functions, as it is the predefined, 1911 // non-templated allocation function we are trying to declare here. 1912 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1913 QualType InitialParamType = 1914 Context.getCanonicalType( 1915 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1916 // FIXME: Do we need to check for default arguments here? 1917 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1918 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1919 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1920 return; 1921 } 1922 } 1923 } 1924 } 1925 1926 QualType BadAllocType; 1927 bool HasBadAllocExceptionSpec 1928 = (Name.getCXXOverloadedOperator() == OO_New || 1929 Name.getCXXOverloadedOperator() == OO_Array_New); 1930 if (HasBadAllocExceptionSpec && !getLangOpts().CPlusPlus11) { 1931 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1932 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1933 } 1934 1935 FunctionProtoType::ExtProtoInfo EPI; 1936 if (HasBadAllocExceptionSpec) { 1937 if (!getLangOpts().CPlusPlus11) { 1938 EPI.ExceptionSpecType = EST_Dynamic; 1939 EPI.NumExceptions = 1; 1940 EPI.Exceptions = &BadAllocType; 1941 } 1942 } else { 1943 EPI.ExceptionSpecType = getLangOpts().CPlusPlus11 ? 1944 EST_BasicNoexcept : EST_DynamicNone; 1945 } 1946 1947 QualType FnType = Context.getFunctionType(Return, Argument, EPI); 1948 FunctionDecl *Alloc = 1949 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1950 SourceLocation(), Name, 1951 FnType, /*TInfo=*/0, SC_None, false, true); 1952 Alloc->setImplicit(); 1953 1954 if (AddMallocAttr) 1955 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1956 1957 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1958 SourceLocation(), 0, 1959 Argument, /*TInfo=*/0, 1960 SC_None, 0); 1961 Alloc->setParams(Param); 1962 1963 // FIXME: Also add this declaration to the IdentifierResolver, but 1964 // make sure it is at the end of the chain to coincide with the 1965 // global scope. 1966 Context.getTranslationUnitDecl()->addDecl(Alloc); 1967} 1968 1969bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1970 DeclarationName Name, 1971 FunctionDecl* &Operator, bool Diagnose) { 1972 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1973 // Try to find operator delete/operator delete[] in class scope. 1974 LookupQualifiedName(Found, RD); 1975 1976 if (Found.isAmbiguous()) 1977 return true; 1978 1979 Found.suppressDiagnostics(); 1980 1981 SmallVector<DeclAccessPair,4> Matches; 1982 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1983 F != FEnd; ++F) { 1984 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1985 1986 // Ignore template operator delete members from the check for a usual 1987 // deallocation function. 1988 if (isa<FunctionTemplateDecl>(ND)) 1989 continue; 1990 1991 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1992 Matches.push_back(F.getPair()); 1993 } 1994 1995 // There's exactly one suitable operator; pick it. 1996 if (Matches.size() == 1) { 1997 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 1998 1999 if (Operator->isDeleted()) { 2000 if (Diagnose) { 2001 Diag(StartLoc, diag::err_deleted_function_use); 2002 NoteDeletedFunction(Operator); 2003 } 2004 return true; 2005 } 2006 2007 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 2008 Matches[0], Diagnose) == AR_inaccessible) 2009 return true; 2010 2011 return false; 2012 2013 // We found multiple suitable operators; complain about the ambiguity. 2014 } else if (!Matches.empty()) { 2015 if (Diagnose) { 2016 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 2017 << Name << RD; 2018 2019 for (SmallVectorImpl<DeclAccessPair>::iterator 2020 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 2021 Diag((*F)->getUnderlyingDecl()->getLocation(), 2022 diag::note_member_declared_here) << Name; 2023 } 2024 return true; 2025 } 2026 2027 // We did find operator delete/operator delete[] declarations, but 2028 // none of them were suitable. 2029 if (!Found.empty()) { 2030 if (Diagnose) { 2031 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 2032 << Name << RD; 2033 2034 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 2035 F != FEnd; ++F) 2036 Diag((*F)->getUnderlyingDecl()->getLocation(), 2037 diag::note_member_declared_here) << Name; 2038 } 2039 return true; 2040 } 2041 2042 // Look for a global declaration. 2043 DeclareGlobalNewDelete(); 2044 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2045 2046 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 2047 Expr *DeallocArgs[1] = { &Null }; 2048 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 2049 DeallocArgs, TUDecl, !Diagnose, 2050 Operator, Diagnose)) 2051 return true; 2052 2053 assert(Operator && "Did not find a deallocation function!"); 2054 return false; 2055} 2056 2057/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 2058/// @code ::delete ptr; @endcode 2059/// or 2060/// @code delete [] ptr; @endcode 2061ExprResult 2062Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 2063 bool ArrayForm, Expr *ExE) { 2064 // C++ [expr.delete]p1: 2065 // The operand shall have a pointer type, or a class type having a single 2066 // conversion function to a pointer type. The result has type void. 2067 // 2068 // DR599 amends "pointer type" to "pointer to object type" in both cases. 2069 2070 ExprResult Ex = Owned(ExE); 2071 FunctionDecl *OperatorDelete = 0; 2072 bool ArrayFormAsWritten = ArrayForm; 2073 bool UsualArrayDeleteWantsSize = false; 2074 2075 if (!Ex.get()->isTypeDependent()) { 2076 // Perform lvalue-to-rvalue cast, if needed. 2077 Ex = DefaultLvalueConversion(Ex.take()); 2078 if (Ex.isInvalid()) 2079 return ExprError(); 2080 2081 QualType Type = Ex.get()->getType(); 2082 2083 if (const RecordType *Record = Type->getAs<RecordType>()) { 2084 if (RequireCompleteType(StartLoc, Type, 2085 diag::err_delete_incomplete_class_type)) 2086 return ExprError(); 2087 2088 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 2089 2090 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 2091 std::pair<CXXRecordDecl::conversion_iterator, 2092 CXXRecordDecl::conversion_iterator> 2093 Conversions = RD->getVisibleConversionFunctions(); 2094 for (CXXRecordDecl::conversion_iterator 2095 I = Conversions.first, E = Conversions.second; I != E; ++I) { 2096 NamedDecl *D = I.getDecl(); 2097 if (isa<UsingShadowDecl>(D)) 2098 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2099 2100 // Skip over templated conversion functions; they aren't considered. 2101 if (isa<FunctionTemplateDecl>(D)) 2102 continue; 2103 2104 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 2105 2106 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 2107 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 2108 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 2109 ObjectPtrConversions.push_back(Conv); 2110 } 2111 if (ObjectPtrConversions.size() == 1) { 2112 // We have a single conversion to a pointer-to-object type. Perform 2113 // that conversion. 2114 // TODO: don't redo the conversion calculation. 2115 ExprResult Res = 2116 PerformImplicitConversion(Ex.get(), 2117 ObjectPtrConversions.front()->getConversionType(), 2118 AA_Converting); 2119 if (Res.isUsable()) { 2120 Ex = Res; 2121 Type = Ex.get()->getType(); 2122 } 2123 } 2124 else if (ObjectPtrConversions.size() > 1) { 2125 Diag(StartLoc, diag::err_ambiguous_delete_operand) 2126 << Type << Ex.get()->getSourceRange(); 2127 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 2128 NoteOverloadCandidate(ObjectPtrConversions[i]); 2129 return ExprError(); 2130 } 2131 } 2132 2133 if (!Type->isPointerType()) 2134 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2135 << Type << Ex.get()->getSourceRange()); 2136 2137 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2138 QualType PointeeElem = Context.getBaseElementType(Pointee); 2139 2140 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2141 return Diag(Ex.get()->getLocStart(), 2142 diag::err_address_space_qualified_delete) 2143 << Pointee.getUnqualifiedType() << AddressSpace; 2144 2145 CXXRecordDecl *PointeeRD = 0; 2146 if (Pointee->isVoidType() && !isSFINAEContext()) { 2147 // The C++ standard bans deleting a pointer to a non-object type, which 2148 // effectively bans deletion of "void*". However, most compilers support 2149 // this, so we treat it as a warning unless we're in a SFINAE context. 2150 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2151 << Type << Ex.get()->getSourceRange(); 2152 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2153 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2154 << Type << Ex.get()->getSourceRange()); 2155 } else if (!Pointee->isDependentType()) { 2156 if (!RequireCompleteType(StartLoc, Pointee, 2157 diag::warn_delete_incomplete, Ex.get())) { 2158 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2159 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2160 } 2161 } 2162 2163 // C++ [expr.delete]p2: 2164 // [Note: a pointer to a const type can be the operand of a 2165 // delete-expression; it is not necessary to cast away the constness 2166 // (5.2.11) of the pointer expression before it is used as the operand 2167 // of the delete-expression. ] 2168 2169 if (Pointee->isArrayType() && !ArrayForm) { 2170 Diag(StartLoc, diag::warn_delete_array_type) 2171 << Type << Ex.get()->getSourceRange() 2172 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2173 ArrayForm = true; 2174 } 2175 2176 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2177 ArrayForm ? OO_Array_Delete : OO_Delete); 2178 2179 if (PointeeRD) { 2180 if (!UseGlobal && 2181 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2182 OperatorDelete)) 2183 return ExprError(); 2184 2185 // If we're allocating an array of records, check whether the 2186 // usual operator delete[] has a size_t parameter. 2187 if (ArrayForm) { 2188 // If the user specifically asked to use the global allocator, 2189 // we'll need to do the lookup into the class. 2190 if (UseGlobal) 2191 UsualArrayDeleteWantsSize = 2192 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2193 2194 // Otherwise, the usual operator delete[] should be the 2195 // function we just found. 2196 else if (isa<CXXMethodDecl>(OperatorDelete)) 2197 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2198 } 2199 2200 if (!PointeeRD->hasIrrelevantDestructor()) 2201 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2202 MarkFunctionReferenced(StartLoc, 2203 const_cast<CXXDestructorDecl*>(Dtor)); 2204 if (DiagnoseUseOfDecl(Dtor, StartLoc)) 2205 return ExprError(); 2206 } 2207 2208 // C++ [expr.delete]p3: 2209 // In the first alternative (delete object), if the static type of the 2210 // object to be deleted is different from its dynamic type, the static 2211 // type shall be a base class of the dynamic type of the object to be 2212 // deleted and the static type shall have a virtual destructor or the 2213 // behavior is undefined. 2214 // 2215 // Note: a final class cannot be derived from, no issue there 2216 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2217 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2218 if (dtor && !dtor->isVirtual()) { 2219 if (PointeeRD->isAbstract()) { 2220 // If the class is abstract, we warn by default, because we're 2221 // sure the code has undefined behavior. 2222 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2223 << PointeeElem; 2224 } else if (!ArrayForm) { 2225 // Otherwise, if this is not an array delete, it's a bit suspect, 2226 // but not necessarily wrong. 2227 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2228 } 2229 } 2230 } 2231 2232 } 2233 2234 if (!OperatorDelete) { 2235 // Look for a global declaration. 2236 DeclareGlobalNewDelete(); 2237 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2238 Expr *Arg = Ex.get(); 2239 Expr *DeallocArgs[1] = { Arg }; 2240 if (!Context.hasSameType(Arg->getType(), Context.VoidPtrTy)) 2241 Arg = ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2242 CK_BitCast, Arg, 0, VK_RValue); 2243 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2244 DeallocArgs, TUDecl, /*AllowMissing=*/false, 2245 OperatorDelete)) 2246 return ExprError(); 2247 } 2248 2249 MarkFunctionReferenced(StartLoc, OperatorDelete); 2250 2251 // Check access and ambiguity of operator delete and destructor. 2252 if (PointeeRD) { 2253 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2254 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2255 PDiag(diag::err_access_dtor) << PointeeElem); 2256 } 2257 } 2258 2259 } 2260 2261 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2262 ArrayFormAsWritten, 2263 UsualArrayDeleteWantsSize, 2264 OperatorDelete, Ex.take(), StartLoc)); 2265} 2266 2267/// \brief Check the use of the given variable as a C++ condition in an if, 2268/// while, do-while, or switch statement. 2269ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2270 SourceLocation StmtLoc, 2271 bool ConvertToBoolean) { 2272 if (ConditionVar->isInvalidDecl()) 2273 return ExprError(); 2274 2275 QualType T = ConditionVar->getType(); 2276 2277 // C++ [stmt.select]p2: 2278 // The declarator shall not specify a function or an array. 2279 if (T->isFunctionType()) 2280 return ExprError(Diag(ConditionVar->getLocation(), 2281 diag::err_invalid_use_of_function_type) 2282 << ConditionVar->getSourceRange()); 2283 else if (T->isArrayType()) 2284 return ExprError(Diag(ConditionVar->getLocation(), 2285 diag::err_invalid_use_of_array_type) 2286 << ConditionVar->getSourceRange()); 2287 2288 ExprResult Condition = 2289 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2290 SourceLocation(), 2291 ConditionVar, 2292 /*enclosing*/ false, 2293 ConditionVar->getLocation(), 2294 ConditionVar->getType().getNonReferenceType(), 2295 VK_LValue)); 2296 2297 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2298 2299 if (ConvertToBoolean) { 2300 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2301 if (Condition.isInvalid()) 2302 return ExprError(); 2303 } 2304 2305 return Condition; 2306} 2307 2308/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2309ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2310 // C++ 6.4p4: 2311 // The value of a condition that is an initialized declaration in a statement 2312 // other than a switch statement is the value of the declared variable 2313 // implicitly converted to type bool. If that conversion is ill-formed, the 2314 // program is ill-formed. 2315 // The value of a condition that is an expression is the value of the 2316 // expression, implicitly converted to bool. 2317 // 2318 return PerformContextuallyConvertToBool(CondExpr); 2319} 2320 2321/// Helper function to determine whether this is the (deprecated) C++ 2322/// conversion from a string literal to a pointer to non-const char or 2323/// non-const wchar_t (for narrow and wide string literals, 2324/// respectively). 2325bool 2326Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2327 // Look inside the implicit cast, if it exists. 2328 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2329 From = Cast->getSubExpr(); 2330 2331 // A string literal (2.13.4) that is not a wide string literal can 2332 // be converted to an rvalue of type "pointer to char"; a wide 2333 // string literal can be converted to an rvalue of type "pointer 2334 // to wchar_t" (C++ 4.2p2). 2335 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2336 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2337 if (const BuiltinType *ToPointeeType 2338 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2339 // This conversion is considered only when there is an 2340 // explicit appropriate pointer target type (C++ 4.2p2). 2341 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2342 switch (StrLit->getKind()) { 2343 case StringLiteral::UTF8: 2344 case StringLiteral::UTF16: 2345 case StringLiteral::UTF32: 2346 // We don't allow UTF literals to be implicitly converted 2347 break; 2348 case StringLiteral::Ascii: 2349 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2350 ToPointeeType->getKind() == BuiltinType::Char_S); 2351 case StringLiteral::Wide: 2352 return ToPointeeType->isWideCharType(); 2353 } 2354 } 2355 } 2356 2357 return false; 2358} 2359 2360static ExprResult BuildCXXCastArgument(Sema &S, 2361 SourceLocation CastLoc, 2362 QualType Ty, 2363 CastKind Kind, 2364 CXXMethodDecl *Method, 2365 DeclAccessPair FoundDecl, 2366 bool HadMultipleCandidates, 2367 Expr *From) { 2368 switch (Kind) { 2369 default: llvm_unreachable("Unhandled cast kind!"); 2370 case CK_ConstructorConversion: { 2371 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2372 SmallVector<Expr*, 8> ConstructorArgs; 2373 2374 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs)) 2375 return ExprError(); 2376 2377 S.CheckConstructorAccess(CastLoc, Constructor, 2378 InitializedEntity::InitializeTemporary(Ty), 2379 Constructor->getAccess()); 2380 2381 ExprResult Result 2382 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2383 ConstructorArgs, HadMultipleCandidates, 2384 /*ListInit*/ false, /*ZeroInit*/ false, 2385 CXXConstructExpr::CK_Complete, SourceRange()); 2386 if (Result.isInvalid()) 2387 return ExprError(); 2388 2389 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2390 } 2391 2392 case CK_UserDefinedConversion: { 2393 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2394 2395 // Create an implicit call expr that calls it. 2396 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method); 2397 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv, 2398 HadMultipleCandidates); 2399 if (Result.isInvalid()) 2400 return ExprError(); 2401 // Record usage of conversion in an implicit cast. 2402 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2403 Result.get()->getType(), 2404 CK_UserDefinedConversion, 2405 Result.get(), 0, 2406 Result.get()->getValueKind())); 2407 2408 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2409 2410 return S.MaybeBindToTemporary(Result.get()); 2411 } 2412 } 2413} 2414 2415/// PerformImplicitConversion - Perform an implicit conversion of the 2416/// expression From to the type ToType using the pre-computed implicit 2417/// conversion sequence ICS. Returns the converted 2418/// expression. Action is the kind of conversion we're performing, 2419/// used in the error message. 2420ExprResult 2421Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2422 const ImplicitConversionSequence &ICS, 2423 AssignmentAction Action, 2424 CheckedConversionKind CCK) { 2425 switch (ICS.getKind()) { 2426 case ImplicitConversionSequence::StandardConversion: { 2427 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2428 Action, CCK); 2429 if (Res.isInvalid()) 2430 return ExprError(); 2431 From = Res.take(); 2432 break; 2433 } 2434 2435 case ImplicitConversionSequence::UserDefinedConversion: { 2436 2437 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2438 CastKind CastKind; 2439 QualType BeforeToType; 2440 assert(FD && "FIXME: aggregate initialization from init list"); 2441 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2442 CastKind = CK_UserDefinedConversion; 2443 2444 // If the user-defined conversion is specified by a conversion function, 2445 // the initial standard conversion sequence converts the source type to 2446 // the implicit object parameter of the conversion function. 2447 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2448 } else { 2449 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2450 CastKind = CK_ConstructorConversion; 2451 // Do no conversion if dealing with ... for the first conversion. 2452 if (!ICS.UserDefined.EllipsisConversion) { 2453 // If the user-defined conversion is specified by a constructor, the 2454 // initial standard conversion sequence converts the source type to the 2455 // type required by the argument of the constructor 2456 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2457 } 2458 } 2459 // Watch out for elipsis conversion. 2460 if (!ICS.UserDefined.EllipsisConversion) { 2461 ExprResult Res = 2462 PerformImplicitConversion(From, BeforeToType, 2463 ICS.UserDefined.Before, AA_Converting, 2464 CCK); 2465 if (Res.isInvalid()) 2466 return ExprError(); 2467 From = Res.take(); 2468 } 2469 2470 ExprResult CastArg 2471 = BuildCXXCastArgument(*this, 2472 From->getLocStart(), 2473 ToType.getNonReferenceType(), 2474 CastKind, cast<CXXMethodDecl>(FD), 2475 ICS.UserDefined.FoundConversionFunction, 2476 ICS.UserDefined.HadMultipleCandidates, 2477 From); 2478 2479 if (CastArg.isInvalid()) 2480 return ExprError(); 2481 2482 From = CastArg.take(); 2483 2484 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2485 AA_Converting, CCK); 2486 } 2487 2488 case ImplicitConversionSequence::AmbiguousConversion: 2489 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2490 PDiag(diag::err_typecheck_ambiguous_condition) 2491 << From->getSourceRange()); 2492 return ExprError(); 2493 2494 case ImplicitConversionSequence::EllipsisConversion: 2495 llvm_unreachable("Cannot perform an ellipsis conversion"); 2496 2497 case ImplicitConversionSequence::BadConversion: 2498 return ExprError(); 2499 } 2500 2501 // Everything went well. 2502 return Owned(From); 2503} 2504 2505/// PerformImplicitConversion - Perform an implicit conversion of the 2506/// expression From to the type ToType by following the standard 2507/// conversion sequence SCS. Returns the converted 2508/// expression. Flavor is the context in which we're performing this 2509/// conversion, for use in error messages. 2510ExprResult 2511Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2512 const StandardConversionSequence& SCS, 2513 AssignmentAction Action, 2514 CheckedConversionKind CCK) { 2515 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2516 2517 // Overall FIXME: we are recomputing too many types here and doing far too 2518 // much extra work. What this means is that we need to keep track of more 2519 // information that is computed when we try the implicit conversion initially, 2520 // so that we don't need to recompute anything here. 2521 QualType FromType = From->getType(); 2522 2523 if (SCS.CopyConstructor) { 2524 // FIXME: When can ToType be a reference type? 2525 assert(!ToType->isReferenceType()); 2526 if (SCS.Second == ICK_Derived_To_Base) { 2527 SmallVector<Expr*, 8> ConstructorArgs; 2528 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2529 From, /*FIXME:ConstructLoc*/SourceLocation(), 2530 ConstructorArgs)) 2531 return ExprError(); 2532 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2533 ToType, SCS.CopyConstructor, 2534 ConstructorArgs, 2535 /*HadMultipleCandidates*/ false, 2536 /*ListInit*/ false, /*ZeroInit*/ false, 2537 CXXConstructExpr::CK_Complete, 2538 SourceRange()); 2539 } 2540 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2541 ToType, SCS.CopyConstructor, 2542 From, /*HadMultipleCandidates*/ false, 2543 /*ListInit*/ false, /*ZeroInit*/ false, 2544 CXXConstructExpr::CK_Complete, 2545 SourceRange()); 2546 } 2547 2548 // Resolve overloaded function references. 2549 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2550 DeclAccessPair Found; 2551 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2552 true, Found); 2553 if (!Fn) 2554 return ExprError(); 2555 2556 if (DiagnoseUseOfDecl(Fn, From->getLocStart())) 2557 return ExprError(); 2558 2559 From = FixOverloadedFunctionReference(From, Found, Fn); 2560 FromType = From->getType(); 2561 } 2562 2563 // Perform the first implicit conversion. 2564 switch (SCS.First) { 2565 case ICK_Identity: 2566 // Nothing to do. 2567 break; 2568 2569 case ICK_Lvalue_To_Rvalue: { 2570 assert(From->getObjectKind() != OK_ObjCProperty); 2571 FromType = FromType.getUnqualifiedType(); 2572 ExprResult FromRes = DefaultLvalueConversion(From); 2573 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2574 From = FromRes.take(); 2575 break; 2576 } 2577 2578 case ICK_Array_To_Pointer: 2579 FromType = Context.getArrayDecayedType(FromType); 2580 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2581 VK_RValue, /*BasePath=*/0, CCK).take(); 2582 break; 2583 2584 case ICK_Function_To_Pointer: 2585 FromType = Context.getPointerType(FromType); 2586 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2587 VK_RValue, /*BasePath=*/0, CCK).take(); 2588 break; 2589 2590 default: 2591 llvm_unreachable("Improper first standard conversion"); 2592 } 2593 2594 // Perform the second implicit conversion 2595 switch (SCS.Second) { 2596 case ICK_Identity: 2597 // If both sides are functions (or pointers/references to them), there could 2598 // be incompatible exception declarations. 2599 if (CheckExceptionSpecCompatibility(From, ToType)) 2600 return ExprError(); 2601 // Nothing else to do. 2602 break; 2603 2604 case ICK_NoReturn_Adjustment: 2605 // If both sides are functions (or pointers/references to them), there could 2606 // be incompatible exception declarations. 2607 if (CheckExceptionSpecCompatibility(From, ToType)) 2608 return ExprError(); 2609 2610 From = ImpCastExprToType(From, ToType, CK_NoOp, 2611 VK_RValue, /*BasePath=*/0, CCK).take(); 2612 break; 2613 2614 case ICK_Integral_Promotion: 2615 case ICK_Integral_Conversion: 2616 if (ToType->isBooleanType()) { 2617 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() && 2618 SCS.Second == ICK_Integral_Promotion && 2619 "only enums with fixed underlying type can promote to bool"); 2620 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean, 2621 VK_RValue, /*BasePath=*/0, CCK).take(); 2622 } else { 2623 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2624 VK_RValue, /*BasePath=*/0, CCK).take(); 2625 } 2626 break; 2627 2628 case ICK_Floating_Promotion: 2629 case ICK_Floating_Conversion: 2630 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2631 VK_RValue, /*BasePath=*/0, CCK).take(); 2632 break; 2633 2634 case ICK_Complex_Promotion: 2635 case ICK_Complex_Conversion: { 2636 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2637 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2638 CastKind CK; 2639 if (FromEl->isRealFloatingType()) { 2640 if (ToEl->isRealFloatingType()) 2641 CK = CK_FloatingComplexCast; 2642 else 2643 CK = CK_FloatingComplexToIntegralComplex; 2644 } else if (ToEl->isRealFloatingType()) { 2645 CK = CK_IntegralComplexToFloatingComplex; 2646 } else { 2647 CK = CK_IntegralComplexCast; 2648 } 2649 From = ImpCastExprToType(From, ToType, CK, 2650 VK_RValue, /*BasePath=*/0, CCK).take(); 2651 break; 2652 } 2653 2654 case ICK_Floating_Integral: 2655 if (ToType->isRealFloatingType()) 2656 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2657 VK_RValue, /*BasePath=*/0, CCK).take(); 2658 else 2659 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2660 VK_RValue, /*BasePath=*/0, CCK).take(); 2661 break; 2662 2663 case ICK_Compatible_Conversion: 2664 From = ImpCastExprToType(From, ToType, CK_NoOp, 2665 VK_RValue, /*BasePath=*/0, CCK).take(); 2666 break; 2667 2668 case ICK_Writeback_Conversion: 2669 case ICK_Pointer_Conversion: { 2670 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2671 // Diagnose incompatible Objective-C conversions 2672 if (Action == AA_Initializing || Action == AA_Assigning) 2673 Diag(From->getLocStart(), 2674 diag::ext_typecheck_convert_incompatible_pointer) 2675 << ToType << From->getType() << Action 2676 << From->getSourceRange() << 0; 2677 else 2678 Diag(From->getLocStart(), 2679 diag::ext_typecheck_convert_incompatible_pointer) 2680 << From->getType() << ToType << Action 2681 << From->getSourceRange() << 0; 2682 2683 if (From->getType()->isObjCObjectPointerType() && 2684 ToType->isObjCObjectPointerType()) 2685 EmitRelatedResultTypeNote(From); 2686 } 2687 else if (getLangOpts().ObjCAutoRefCount && 2688 !CheckObjCARCUnavailableWeakConversion(ToType, 2689 From->getType())) { 2690 if (Action == AA_Initializing) 2691 Diag(From->getLocStart(), 2692 diag::err_arc_weak_unavailable_assign); 2693 else 2694 Diag(From->getLocStart(), 2695 diag::err_arc_convesion_of_weak_unavailable) 2696 << (Action == AA_Casting) << From->getType() << ToType 2697 << From->getSourceRange(); 2698 } 2699 2700 CastKind Kind = CK_Invalid; 2701 CXXCastPath BasePath; 2702 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2703 return ExprError(); 2704 2705 // Make sure we extend blocks if necessary. 2706 // FIXME: doing this here is really ugly. 2707 if (Kind == CK_BlockPointerToObjCPointerCast) { 2708 ExprResult E = From; 2709 (void) PrepareCastToObjCObjectPointer(E); 2710 From = E.take(); 2711 } 2712 2713 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2714 .take(); 2715 break; 2716 } 2717 2718 case ICK_Pointer_Member: { 2719 CastKind Kind = CK_Invalid; 2720 CXXCastPath BasePath; 2721 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2722 return ExprError(); 2723 if (CheckExceptionSpecCompatibility(From, ToType)) 2724 return ExprError(); 2725 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2726 .take(); 2727 break; 2728 } 2729 2730 case ICK_Boolean_Conversion: 2731 // Perform half-to-boolean conversion via float. 2732 if (From->getType()->isHalfType()) { 2733 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2734 FromType = Context.FloatTy; 2735 } 2736 2737 From = ImpCastExprToType(From, Context.BoolTy, 2738 ScalarTypeToBooleanCastKind(FromType), 2739 VK_RValue, /*BasePath=*/0, CCK).take(); 2740 break; 2741 2742 case ICK_Derived_To_Base: { 2743 CXXCastPath BasePath; 2744 if (CheckDerivedToBaseConversion(From->getType(), 2745 ToType.getNonReferenceType(), 2746 From->getLocStart(), 2747 From->getSourceRange(), 2748 &BasePath, 2749 CStyle)) 2750 return ExprError(); 2751 2752 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2753 CK_DerivedToBase, From->getValueKind(), 2754 &BasePath, CCK).take(); 2755 break; 2756 } 2757 2758 case ICK_Vector_Conversion: 2759 From = ImpCastExprToType(From, ToType, CK_BitCast, 2760 VK_RValue, /*BasePath=*/0, CCK).take(); 2761 break; 2762 2763 case ICK_Vector_Splat: 2764 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2765 VK_RValue, /*BasePath=*/0, CCK).take(); 2766 break; 2767 2768 case ICK_Complex_Real: 2769 // Case 1. x -> _Complex y 2770 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2771 QualType ElType = ToComplex->getElementType(); 2772 bool isFloatingComplex = ElType->isRealFloatingType(); 2773 2774 // x -> y 2775 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2776 // do nothing 2777 } else if (From->getType()->isRealFloatingType()) { 2778 From = ImpCastExprToType(From, ElType, 2779 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2780 } else { 2781 assert(From->getType()->isIntegerType()); 2782 From = ImpCastExprToType(From, ElType, 2783 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2784 } 2785 // y -> _Complex y 2786 From = ImpCastExprToType(From, ToType, 2787 isFloatingComplex ? CK_FloatingRealToComplex 2788 : CK_IntegralRealToComplex).take(); 2789 2790 // Case 2. _Complex x -> y 2791 } else { 2792 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2793 assert(FromComplex); 2794 2795 QualType ElType = FromComplex->getElementType(); 2796 bool isFloatingComplex = ElType->isRealFloatingType(); 2797 2798 // _Complex x -> x 2799 From = ImpCastExprToType(From, ElType, 2800 isFloatingComplex ? CK_FloatingComplexToReal 2801 : CK_IntegralComplexToReal, 2802 VK_RValue, /*BasePath=*/0, CCK).take(); 2803 2804 // x -> y 2805 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2806 // do nothing 2807 } else if (ToType->isRealFloatingType()) { 2808 From = ImpCastExprToType(From, ToType, 2809 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2810 VK_RValue, /*BasePath=*/0, CCK).take(); 2811 } else { 2812 assert(ToType->isIntegerType()); 2813 From = ImpCastExprToType(From, ToType, 2814 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2815 VK_RValue, /*BasePath=*/0, CCK).take(); 2816 } 2817 } 2818 break; 2819 2820 case ICK_Block_Pointer_Conversion: { 2821 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2822 VK_RValue, /*BasePath=*/0, CCK).take(); 2823 break; 2824 } 2825 2826 case ICK_TransparentUnionConversion: { 2827 ExprResult FromRes = Owned(From); 2828 Sema::AssignConvertType ConvTy = 2829 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2830 if (FromRes.isInvalid()) 2831 return ExprError(); 2832 From = FromRes.take(); 2833 assert ((ConvTy == Sema::Compatible) && 2834 "Improper transparent union conversion"); 2835 (void)ConvTy; 2836 break; 2837 } 2838 2839 case ICK_Zero_Event_Conversion: 2840 From = ImpCastExprToType(From, ToType, 2841 CK_ZeroToOCLEvent, 2842 From->getValueKind()).take(); 2843 break; 2844 2845 case ICK_Lvalue_To_Rvalue: 2846 case ICK_Array_To_Pointer: 2847 case ICK_Function_To_Pointer: 2848 case ICK_Qualification: 2849 case ICK_Num_Conversion_Kinds: 2850 llvm_unreachable("Improper second standard conversion"); 2851 } 2852 2853 switch (SCS.Third) { 2854 case ICK_Identity: 2855 // Nothing to do. 2856 break; 2857 2858 case ICK_Qualification: { 2859 // The qualification keeps the category of the inner expression, unless the 2860 // target type isn't a reference. 2861 ExprValueKind VK = ToType->isReferenceType() ? 2862 From->getValueKind() : VK_RValue; 2863 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2864 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2865 2866 if (SCS.DeprecatedStringLiteralToCharPtr && 2867 !getLangOpts().WritableStrings) 2868 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2869 << ToType.getNonReferenceType(); 2870 2871 break; 2872 } 2873 2874 default: 2875 llvm_unreachable("Improper third standard conversion"); 2876 } 2877 2878 // If this conversion sequence involved a scalar -> atomic conversion, perform 2879 // that conversion now. 2880 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) 2881 if (Context.hasSameType(ToAtomic->getValueType(), From->getType())) 2882 From = ImpCastExprToType(From, ToType, CK_NonAtomicToAtomic, VK_RValue, 0, 2883 CCK).take(); 2884 2885 return Owned(From); 2886} 2887 2888ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2889 SourceLocation KWLoc, 2890 ParsedType Ty, 2891 SourceLocation RParen) { 2892 TypeSourceInfo *TSInfo; 2893 QualType T = GetTypeFromParser(Ty, &TSInfo); 2894 2895 if (!TSInfo) 2896 TSInfo = Context.getTrivialTypeSourceInfo(T); 2897 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2898} 2899 2900/// \brief Check the completeness of a type in a unary type trait. 2901/// 2902/// If the particular type trait requires a complete type, tries to complete 2903/// it. If completing the type fails, a diagnostic is emitted and false 2904/// returned. If completing the type succeeds or no completion was required, 2905/// returns true. 2906static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2907 UnaryTypeTrait UTT, 2908 SourceLocation Loc, 2909 QualType ArgTy) { 2910 // C++0x [meta.unary.prop]p3: 2911 // For all of the class templates X declared in this Clause, instantiating 2912 // that template with a template argument that is a class template 2913 // specialization may result in the implicit instantiation of the template 2914 // argument if and only if the semantics of X require that the argument 2915 // must be a complete type. 2916 // We apply this rule to all the type trait expressions used to implement 2917 // these class templates. We also try to follow any GCC documented behavior 2918 // in these expressions to ensure portability of standard libraries. 2919 switch (UTT) { 2920 // is_complete_type somewhat obviously cannot require a complete type. 2921 case UTT_IsCompleteType: 2922 // Fall-through 2923 2924 // These traits are modeled on the type predicates in C++0x 2925 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2926 // requiring a complete type, as whether or not they return true cannot be 2927 // impacted by the completeness of the type. 2928 case UTT_IsVoid: 2929 case UTT_IsIntegral: 2930 case UTT_IsFloatingPoint: 2931 case UTT_IsArray: 2932 case UTT_IsPointer: 2933 case UTT_IsLvalueReference: 2934 case UTT_IsRvalueReference: 2935 case UTT_IsMemberFunctionPointer: 2936 case UTT_IsMemberObjectPointer: 2937 case UTT_IsEnum: 2938 case UTT_IsUnion: 2939 case UTT_IsClass: 2940 case UTT_IsFunction: 2941 case UTT_IsReference: 2942 case UTT_IsArithmetic: 2943 case UTT_IsFundamental: 2944 case UTT_IsObject: 2945 case UTT_IsScalar: 2946 case UTT_IsCompound: 2947 case UTT_IsMemberPointer: 2948 // Fall-through 2949 2950 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2951 // which requires some of its traits to have the complete type. However, 2952 // the completeness of the type cannot impact these traits' semantics, and 2953 // so they don't require it. This matches the comments on these traits in 2954 // Table 49. 2955 case UTT_IsConst: 2956 case UTT_IsVolatile: 2957 case UTT_IsSigned: 2958 case UTT_IsUnsigned: 2959 return true; 2960 2961 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2962 // applied to a complete type. 2963 case UTT_IsTrivial: 2964 case UTT_IsTriviallyCopyable: 2965 case UTT_IsStandardLayout: 2966 case UTT_IsPOD: 2967 case UTT_IsLiteral: 2968 case UTT_IsEmpty: 2969 case UTT_IsPolymorphic: 2970 case UTT_IsAbstract: 2971 case UTT_IsInterfaceClass: 2972 // Fall-through 2973 2974 // These traits require a complete type. 2975 case UTT_IsFinal: 2976 2977 // These trait expressions are designed to help implement predicates in 2978 // [meta.unary.prop] despite not being named the same. They are specified 2979 // by both GCC and the Embarcadero C++ compiler, and require the complete 2980 // type due to the overarching C++0x type predicates being implemented 2981 // requiring the complete type. 2982 case UTT_HasNothrowAssign: 2983 case UTT_HasNothrowMoveAssign: 2984 case UTT_HasNothrowConstructor: 2985 case UTT_HasNothrowCopy: 2986 case UTT_HasTrivialAssign: 2987 case UTT_HasTrivialMoveAssign: 2988 case UTT_HasTrivialDefaultConstructor: 2989 case UTT_HasTrivialMoveConstructor: 2990 case UTT_HasTrivialCopy: 2991 case UTT_HasTrivialDestructor: 2992 case UTT_HasVirtualDestructor: 2993 // Arrays of unknown bound are expressly allowed. 2994 QualType ElTy = ArgTy; 2995 if (ArgTy->isIncompleteArrayType()) 2996 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 2997 2998 // The void type is expressly allowed. 2999 if (ElTy->isVoidType()) 3000 return true; 3001 3002 return !S.RequireCompleteType( 3003 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 3004 } 3005 llvm_unreachable("Type trait not handled by switch"); 3006} 3007 3008static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op, 3009 Sema &Self, SourceLocation KeyLoc, ASTContext &C, 3010 bool (CXXRecordDecl::*HasTrivial)() const, 3011 bool (CXXRecordDecl::*HasNonTrivial)() const, 3012 bool (CXXMethodDecl::*IsDesiredOp)() const) 3013{ 3014 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3015 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)()) 3016 return true; 3017 3018 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op); 3019 DeclarationNameInfo NameInfo(Name, KeyLoc); 3020 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName); 3021 if (Self.LookupQualifiedName(Res, RD)) { 3022 bool FoundOperator = false; 3023 Res.suppressDiagnostics(); 3024 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3025 Op != OpEnd; ++Op) { 3026 if (isa<FunctionTemplateDecl>(*Op)) 3027 continue; 3028 3029 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3030 if((Operator->*IsDesiredOp)()) { 3031 FoundOperator = true; 3032 const FunctionProtoType *CPT = 3033 Operator->getType()->getAs<FunctionProtoType>(); 3034 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3035 if (!CPT || !CPT->isNothrow(Self.Context)) 3036 return false; 3037 } 3038 } 3039 return FoundOperator; 3040 } 3041 return false; 3042} 3043 3044static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 3045 SourceLocation KeyLoc, QualType T) { 3046 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3047 3048 ASTContext &C = Self.Context; 3049 switch(UTT) { 3050 // Type trait expressions corresponding to the primary type category 3051 // predicates in C++0x [meta.unary.cat]. 3052 case UTT_IsVoid: 3053 return T->isVoidType(); 3054 case UTT_IsIntegral: 3055 return T->isIntegralType(C); 3056 case UTT_IsFloatingPoint: 3057 return T->isFloatingType(); 3058 case UTT_IsArray: 3059 return T->isArrayType(); 3060 case UTT_IsPointer: 3061 return T->isPointerType(); 3062 case UTT_IsLvalueReference: 3063 return T->isLValueReferenceType(); 3064 case UTT_IsRvalueReference: 3065 return T->isRValueReferenceType(); 3066 case UTT_IsMemberFunctionPointer: 3067 return T->isMemberFunctionPointerType(); 3068 case UTT_IsMemberObjectPointer: 3069 return T->isMemberDataPointerType(); 3070 case UTT_IsEnum: 3071 return T->isEnumeralType(); 3072 case UTT_IsUnion: 3073 return T->isUnionType(); 3074 case UTT_IsClass: 3075 return T->isClassType() || T->isStructureType() || T->isInterfaceType(); 3076 case UTT_IsFunction: 3077 return T->isFunctionType(); 3078 3079 // Type trait expressions which correspond to the convenient composition 3080 // predicates in C++0x [meta.unary.comp]. 3081 case UTT_IsReference: 3082 return T->isReferenceType(); 3083 case UTT_IsArithmetic: 3084 return T->isArithmeticType() && !T->isEnumeralType(); 3085 case UTT_IsFundamental: 3086 return T->isFundamentalType(); 3087 case UTT_IsObject: 3088 return T->isObjectType(); 3089 case UTT_IsScalar: 3090 // Note: semantic analysis depends on Objective-C lifetime types to be 3091 // considered scalar types. However, such types do not actually behave 3092 // like scalar types at run time (since they may require retain/release 3093 // operations), so we report them as non-scalar. 3094 if (T->isObjCLifetimeType()) { 3095 switch (T.getObjCLifetime()) { 3096 case Qualifiers::OCL_None: 3097 case Qualifiers::OCL_ExplicitNone: 3098 return true; 3099 3100 case Qualifiers::OCL_Strong: 3101 case Qualifiers::OCL_Weak: 3102 case Qualifiers::OCL_Autoreleasing: 3103 return false; 3104 } 3105 } 3106 3107 return T->isScalarType(); 3108 case UTT_IsCompound: 3109 return T->isCompoundType(); 3110 case UTT_IsMemberPointer: 3111 return T->isMemberPointerType(); 3112 3113 // Type trait expressions which correspond to the type property predicates 3114 // in C++0x [meta.unary.prop]. 3115 case UTT_IsConst: 3116 return T.isConstQualified(); 3117 case UTT_IsVolatile: 3118 return T.isVolatileQualified(); 3119 case UTT_IsTrivial: 3120 return T.isTrivialType(Self.Context); 3121 case UTT_IsTriviallyCopyable: 3122 return T.isTriviallyCopyableType(Self.Context); 3123 case UTT_IsStandardLayout: 3124 return T->isStandardLayoutType(); 3125 case UTT_IsPOD: 3126 return T.isPODType(Self.Context); 3127 case UTT_IsLiteral: 3128 return T->isLiteralType(Self.Context); 3129 case UTT_IsEmpty: 3130 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3131 return !RD->isUnion() && RD->isEmpty(); 3132 return false; 3133 case UTT_IsPolymorphic: 3134 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3135 return RD->isPolymorphic(); 3136 return false; 3137 case UTT_IsAbstract: 3138 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3139 return RD->isAbstract(); 3140 return false; 3141 case UTT_IsInterfaceClass: 3142 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3143 return RD->isInterface(); 3144 return false; 3145 case UTT_IsFinal: 3146 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3147 return RD->hasAttr<FinalAttr>(); 3148 return false; 3149 case UTT_IsSigned: 3150 return T->isSignedIntegerType(); 3151 case UTT_IsUnsigned: 3152 return T->isUnsignedIntegerType(); 3153 3154 // Type trait expressions which query classes regarding their construction, 3155 // destruction, and copying. Rather than being based directly on the 3156 // related type predicates in the standard, they are specified by both 3157 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 3158 // specifications. 3159 // 3160 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 3161 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3162 // 3163 // Note that these builtins do not behave as documented in g++: if a class 3164 // has both a trivial and a non-trivial special member of a particular kind, 3165 // they return false! For now, we emulate this behavior. 3166 // FIXME: This appears to be a g++ bug: more complex cases reveal that it 3167 // does not correctly compute triviality in the presence of multiple special 3168 // members of the same kind. Revisit this once the g++ bug is fixed. 3169 case UTT_HasTrivialDefaultConstructor: 3170 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3171 // If __is_pod (type) is true then the trait is true, else if type is 3172 // a cv class or union type (or array thereof) with a trivial default 3173 // constructor ([class.ctor]) then the trait is true, else it is false. 3174 if (T.isPODType(Self.Context)) 3175 return true; 3176 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3177 return RD->hasTrivialDefaultConstructor() && 3178 !RD->hasNonTrivialDefaultConstructor(); 3179 return false; 3180 case UTT_HasTrivialMoveConstructor: 3181 // This trait is implemented by MSVC 2012 and needed to parse the 3182 // standard library headers. Specifically this is used as the logic 3183 // behind std::is_trivially_move_constructible (20.9.4.3). 3184 if (T.isPODType(Self.Context)) 3185 return true; 3186 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3187 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor(); 3188 return false; 3189 case UTT_HasTrivialCopy: 3190 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3191 // If __is_pod (type) is true or type is a reference type then 3192 // the trait is true, else if type is a cv class or union type 3193 // with a trivial copy constructor ([class.copy]) then the trait 3194 // is true, else it is false. 3195 if (T.isPODType(Self.Context) || T->isReferenceType()) 3196 return true; 3197 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3198 return RD->hasTrivialCopyConstructor() && 3199 !RD->hasNonTrivialCopyConstructor(); 3200 return false; 3201 case UTT_HasTrivialMoveAssign: 3202 // This trait is implemented by MSVC 2012 and needed to parse the 3203 // standard library headers. Specifically it is used as the logic 3204 // behind std::is_trivially_move_assignable (20.9.4.3) 3205 if (T.isPODType(Self.Context)) 3206 return true; 3207 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3208 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment(); 3209 return false; 3210 case UTT_HasTrivialAssign: 3211 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3212 // If type is const qualified or is a reference type then the 3213 // trait is false. Otherwise if __is_pod (type) is true then the 3214 // trait is true, else if type is a cv class or union type with 3215 // a trivial copy assignment ([class.copy]) then the trait is 3216 // true, else it is false. 3217 // Note: the const and reference restrictions are interesting, 3218 // given that const and reference members don't prevent a class 3219 // from having a trivial copy assignment operator (but do cause 3220 // errors if the copy assignment operator is actually used, q.v. 3221 // [class.copy]p12). 3222 3223 if (T.isConstQualified()) 3224 return false; 3225 if (T.isPODType(Self.Context)) 3226 return true; 3227 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3228 return RD->hasTrivialCopyAssignment() && 3229 !RD->hasNonTrivialCopyAssignment(); 3230 return false; 3231 case UTT_HasTrivialDestructor: 3232 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3233 // If __is_pod (type) is true or type is a reference type 3234 // then the trait is true, else if type is a cv class or union 3235 // type (or array thereof) with a trivial destructor 3236 // ([class.dtor]) then the trait is true, else it is 3237 // false. 3238 if (T.isPODType(Self.Context) || T->isReferenceType()) 3239 return true; 3240 3241 // Objective-C++ ARC: autorelease types don't require destruction. 3242 if (T->isObjCLifetimeType() && 3243 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3244 return true; 3245 3246 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3247 return RD->hasTrivialDestructor(); 3248 return false; 3249 // TODO: Propagate nothrowness for implicitly declared special members. 3250 case UTT_HasNothrowAssign: 3251 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3252 // If type is const qualified or is a reference type then the 3253 // trait is false. Otherwise if __has_trivial_assign (type) 3254 // is true then the trait is true, else if type is a cv class 3255 // or union type with copy assignment operators that are known 3256 // not to throw an exception then the trait is true, else it is 3257 // false. 3258 if (C.getBaseElementType(T).isConstQualified()) 3259 return false; 3260 if (T->isReferenceType()) 3261 return false; 3262 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3263 return true; 3264 3265 if (const RecordType *RT = T->getAs<RecordType>()) 3266 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C, 3267 &CXXRecordDecl::hasTrivialCopyAssignment, 3268 &CXXRecordDecl::hasNonTrivialCopyAssignment, 3269 &CXXMethodDecl::isCopyAssignmentOperator); 3270 return false; 3271 case UTT_HasNothrowMoveAssign: 3272 // This trait is implemented by MSVC 2012 and needed to parse the 3273 // standard library headers. Specifically this is used as the logic 3274 // behind std::is_nothrow_move_assignable (20.9.4.3). 3275 if (T.isPODType(Self.Context)) 3276 return true; 3277 3278 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) 3279 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C, 3280 &CXXRecordDecl::hasTrivialMoveAssignment, 3281 &CXXRecordDecl::hasNonTrivialMoveAssignment, 3282 &CXXMethodDecl::isMoveAssignmentOperator); 3283 return false; 3284 case UTT_HasNothrowCopy: 3285 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3286 // If __has_trivial_copy (type) is true then the trait is true, else 3287 // if type is a cv class or union type with copy constructors that are 3288 // known not to throw an exception then the trait is true, else it is 3289 // false. 3290 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3291 return true; 3292 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) { 3293 if (RD->hasTrivialCopyConstructor() && 3294 !RD->hasNonTrivialCopyConstructor()) 3295 return true; 3296 3297 bool FoundConstructor = false; 3298 unsigned FoundTQs; 3299 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3300 for (DeclContext::lookup_const_iterator Con = R.begin(), 3301 ConEnd = R.end(); Con != ConEnd; ++Con) { 3302 // A template constructor is never a copy constructor. 3303 // FIXME: However, it may actually be selected at the actual overload 3304 // resolution point. 3305 if (isa<FunctionTemplateDecl>(*Con)) 3306 continue; 3307 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3308 if (Constructor->isCopyConstructor(FoundTQs)) { 3309 FoundConstructor = true; 3310 const FunctionProtoType *CPT 3311 = Constructor->getType()->getAs<FunctionProtoType>(); 3312 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3313 if (!CPT) 3314 return false; 3315 // FIXME: check whether evaluating default arguments can throw. 3316 // For now, we'll be conservative and assume that they can throw. 3317 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3318 return false; 3319 } 3320 } 3321 3322 return FoundConstructor; 3323 } 3324 return false; 3325 case UTT_HasNothrowConstructor: 3326 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3327 // If __has_trivial_constructor (type) is true then the trait is 3328 // true, else if type is a cv class or union type (or array 3329 // thereof) with a default constructor that is known not to 3330 // throw an exception then the trait is true, else it is false. 3331 if (T.isPODType(C) || T->isObjCLifetimeType()) 3332 return true; 3333 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) { 3334 if (RD->hasTrivialDefaultConstructor() && 3335 !RD->hasNonTrivialDefaultConstructor()) 3336 return true; 3337 3338 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3339 for (DeclContext::lookup_const_iterator Con = R.begin(), 3340 ConEnd = R.end(); Con != ConEnd; ++Con) { 3341 // FIXME: In C++0x, a constructor template can be a default constructor. 3342 if (isa<FunctionTemplateDecl>(*Con)) 3343 continue; 3344 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3345 if (Constructor->isDefaultConstructor()) { 3346 const FunctionProtoType *CPT 3347 = Constructor->getType()->getAs<FunctionProtoType>(); 3348 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3349 if (!CPT) 3350 return false; 3351 // TODO: check whether evaluating default arguments can throw. 3352 // For now, we'll be conservative and assume that they can throw. 3353 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3354 } 3355 } 3356 } 3357 return false; 3358 case UTT_HasVirtualDestructor: 3359 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3360 // If type is a class type with a virtual destructor ([class.dtor]) 3361 // then the trait is true, else it is false. 3362 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3363 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3364 return Destructor->isVirtual(); 3365 return false; 3366 3367 // These type trait expressions are modeled on the specifications for the 3368 // Embarcadero C++0x type trait functions: 3369 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3370 case UTT_IsCompleteType: 3371 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3372 // Returns True if and only if T is a complete type at the point of the 3373 // function call. 3374 return !T->isIncompleteType(); 3375 } 3376 llvm_unreachable("Type trait not covered by switch"); 3377} 3378 3379ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3380 SourceLocation KWLoc, 3381 TypeSourceInfo *TSInfo, 3382 SourceLocation RParen) { 3383 QualType T = TSInfo->getType(); 3384 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3385 return ExprError(); 3386 3387 bool Value = false; 3388 if (!T->isDependentType()) 3389 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3390 3391 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3392 RParen, Context.BoolTy)); 3393} 3394 3395ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3396 SourceLocation KWLoc, 3397 ParsedType LhsTy, 3398 ParsedType RhsTy, 3399 SourceLocation RParen) { 3400 TypeSourceInfo *LhsTSInfo; 3401 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3402 if (!LhsTSInfo) 3403 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3404 3405 TypeSourceInfo *RhsTSInfo; 3406 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3407 if (!RhsTSInfo) 3408 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3409 3410 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3411} 3412 3413/// \brief Determine whether T has a non-trivial Objective-C lifetime in 3414/// ARC mode. 3415static bool hasNontrivialObjCLifetime(QualType T) { 3416 switch (T.getObjCLifetime()) { 3417 case Qualifiers::OCL_ExplicitNone: 3418 return false; 3419 3420 case Qualifiers::OCL_Strong: 3421 case Qualifiers::OCL_Weak: 3422 case Qualifiers::OCL_Autoreleasing: 3423 return true; 3424 3425 case Qualifiers::OCL_None: 3426 return T->isObjCLifetimeType(); 3427 } 3428 3429 llvm_unreachable("Unknown ObjC lifetime qualifier"); 3430} 3431 3432static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc, 3433 ArrayRef<TypeSourceInfo *> Args, 3434 SourceLocation RParenLoc) { 3435 switch (Kind) { 3436 case clang::TT_IsTriviallyConstructible: { 3437 // C++11 [meta.unary.prop]: 3438 // is_trivially_constructible is defined as: 3439 // 3440 // is_constructible<T, Args...>::value is true and the variable 3441 // definition for is_constructible, as defined below, is known to call no 3442 // operation that is not trivial. 3443 // 3444 // The predicate condition for a template specialization 3445 // is_constructible<T, Args...> shall be satisfied if and only if the 3446 // following variable definition would be well-formed for some invented 3447 // variable t: 3448 // 3449 // T t(create<Args>()...); 3450 if (Args.empty()) { 3451 S.Diag(KWLoc, diag::err_type_trait_arity) 3452 << 1 << 1 << 1 << (int)Args.size(); 3453 return false; 3454 } 3455 3456 bool SawVoid = false; 3457 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3458 if (Args[I]->getType()->isVoidType()) { 3459 SawVoid = true; 3460 continue; 3461 } 3462 3463 if (!Args[I]->getType()->isIncompleteType() && 3464 S.RequireCompleteType(KWLoc, Args[I]->getType(), 3465 diag::err_incomplete_type_used_in_type_trait_expr)) 3466 return false; 3467 } 3468 3469 // If any argument was 'void', of course it won't type-check. 3470 if (SawVoid) 3471 return false; 3472 3473 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs; 3474 SmallVector<Expr *, 2> ArgExprs; 3475 ArgExprs.reserve(Args.size() - 1); 3476 for (unsigned I = 1, N = Args.size(); I != N; ++I) { 3477 QualType T = Args[I]->getType(); 3478 if (T->isObjectType() || T->isFunctionType()) 3479 T = S.Context.getRValueReferenceType(T); 3480 OpaqueArgExprs.push_back( 3481 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(), 3482 T.getNonLValueExprType(S.Context), 3483 Expr::getValueKindForType(T))); 3484 ArgExprs.push_back(&OpaqueArgExprs.back()); 3485 } 3486 3487 // Perform the initialization in an unevaluated context within a SFINAE 3488 // trap at translation unit scope. 3489 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated); 3490 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true); 3491 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); 3492 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0])); 3493 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc, 3494 RParenLoc)); 3495 InitializationSequence Init(S, To, InitKind, ArgExprs); 3496 if (Init.Failed()) 3497 return false; 3498 3499 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs); 3500 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3501 return false; 3502 3503 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3504 // lifetime, this is a non-trivial construction. 3505 if (S.getLangOpts().ObjCAutoRefCount && 3506 hasNontrivialObjCLifetime(Args[0]->getType().getNonReferenceType())) 3507 return false; 3508 3509 // The initialization succeeded; now make sure there are no non-trivial 3510 // calls. 3511 return !Result.get()->hasNonTrivialCall(S.Context); 3512 } 3513 } 3514 3515 return false; 3516} 3517 3518ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3519 ArrayRef<TypeSourceInfo *> Args, 3520 SourceLocation RParenLoc) { 3521 bool Dependent = false; 3522 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3523 if (Args[I]->getType()->isDependentType()) { 3524 Dependent = true; 3525 break; 3526 } 3527 } 3528 3529 bool Value = false; 3530 if (!Dependent) 3531 Value = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc); 3532 3533 return TypeTraitExpr::Create(Context, Context.BoolTy, KWLoc, Kind, 3534 Args, RParenLoc, Value); 3535} 3536 3537ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3538 ArrayRef<ParsedType> Args, 3539 SourceLocation RParenLoc) { 3540 SmallVector<TypeSourceInfo *, 4> ConvertedArgs; 3541 ConvertedArgs.reserve(Args.size()); 3542 3543 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3544 TypeSourceInfo *TInfo; 3545 QualType T = GetTypeFromParser(Args[I], &TInfo); 3546 if (!TInfo) 3547 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc); 3548 3549 ConvertedArgs.push_back(TInfo); 3550 } 3551 3552 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc); 3553} 3554 3555static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3556 QualType LhsT, QualType RhsT, 3557 SourceLocation KeyLoc) { 3558 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3559 "Cannot evaluate traits of dependent types"); 3560 3561 switch(BTT) { 3562 case BTT_IsBaseOf: { 3563 // C++0x [meta.rel]p2 3564 // Base is a base class of Derived without regard to cv-qualifiers or 3565 // Base and Derived are not unions and name the same class type without 3566 // regard to cv-qualifiers. 3567 3568 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3569 if (!lhsRecord) return false; 3570 3571 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3572 if (!rhsRecord) return false; 3573 3574 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3575 == (lhsRecord == rhsRecord)); 3576 3577 if (lhsRecord == rhsRecord) 3578 return !lhsRecord->getDecl()->isUnion(); 3579 3580 // C++0x [meta.rel]p2: 3581 // If Base and Derived are class types and are different types 3582 // (ignoring possible cv-qualifiers) then Derived shall be a 3583 // complete type. 3584 if (Self.RequireCompleteType(KeyLoc, RhsT, 3585 diag::err_incomplete_type_used_in_type_trait_expr)) 3586 return false; 3587 3588 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3589 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3590 } 3591 case BTT_IsSame: 3592 return Self.Context.hasSameType(LhsT, RhsT); 3593 case BTT_TypeCompatible: 3594 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3595 RhsT.getUnqualifiedType()); 3596 case BTT_IsConvertible: 3597 case BTT_IsConvertibleTo: { 3598 // C++0x [meta.rel]p4: 3599 // Given the following function prototype: 3600 // 3601 // template <class T> 3602 // typename add_rvalue_reference<T>::type create(); 3603 // 3604 // the predicate condition for a template specialization 3605 // is_convertible<From, To> shall be satisfied if and only if 3606 // the return expression in the following code would be 3607 // well-formed, including any implicit conversions to the return 3608 // type of the function: 3609 // 3610 // To test() { 3611 // return create<From>(); 3612 // } 3613 // 3614 // Access checking is performed as if in a context unrelated to To and 3615 // From. Only the validity of the immediate context of the expression 3616 // of the return-statement (including conversions to the return type) 3617 // is considered. 3618 // 3619 // We model the initialization as a copy-initialization of a temporary 3620 // of the appropriate type, which for this expression is identical to the 3621 // return statement (since NRVO doesn't apply). 3622 3623 // Functions aren't allowed to return function or array types. 3624 if (RhsT->isFunctionType() || RhsT->isArrayType()) 3625 return false; 3626 3627 // A return statement in a void function must have void type. 3628 if (RhsT->isVoidType()) 3629 return LhsT->isVoidType(); 3630 3631 // A function definition requires a complete, non-abstract return type. 3632 if (Self.RequireCompleteType(KeyLoc, RhsT, 0) || 3633 Self.RequireNonAbstractType(KeyLoc, RhsT, 0)) 3634 return false; 3635 3636 // Compute the result of add_rvalue_reference. 3637 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3638 LhsT = Self.Context.getRValueReferenceType(LhsT); 3639 3640 // Build a fake source and destination for initialization. 3641 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3642 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3643 Expr::getValueKindForType(LhsT)); 3644 Expr *FromPtr = &From; 3645 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3646 SourceLocation())); 3647 3648 // Perform the initialization in an unevaluated context within a SFINAE 3649 // trap at translation unit scope. 3650 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3651 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3652 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3653 InitializationSequence Init(Self, To, Kind, FromPtr); 3654 if (Init.Failed()) 3655 return false; 3656 3657 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr); 3658 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3659 } 3660 3661 case BTT_IsTriviallyAssignable: { 3662 // C++11 [meta.unary.prop]p3: 3663 // is_trivially_assignable is defined as: 3664 // is_assignable<T, U>::value is true and the assignment, as defined by 3665 // is_assignable, is known to call no operation that is not trivial 3666 // 3667 // is_assignable is defined as: 3668 // The expression declval<T>() = declval<U>() is well-formed when 3669 // treated as an unevaluated operand (Clause 5). 3670 // 3671 // For both, T and U shall be complete types, (possibly cv-qualified) 3672 // void, or arrays of unknown bound. 3673 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() && 3674 Self.RequireCompleteType(KeyLoc, LhsT, 3675 diag::err_incomplete_type_used_in_type_trait_expr)) 3676 return false; 3677 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() && 3678 Self.RequireCompleteType(KeyLoc, RhsT, 3679 diag::err_incomplete_type_used_in_type_trait_expr)) 3680 return false; 3681 3682 // cv void is never assignable. 3683 if (LhsT->isVoidType() || RhsT->isVoidType()) 3684 return false; 3685 3686 // Build expressions that emulate the effect of declval<T>() and 3687 // declval<U>(). 3688 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3689 LhsT = Self.Context.getRValueReferenceType(LhsT); 3690 if (RhsT->isObjectType() || RhsT->isFunctionType()) 3691 RhsT = Self.Context.getRValueReferenceType(RhsT); 3692 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3693 Expr::getValueKindForType(LhsT)); 3694 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context), 3695 Expr::getValueKindForType(RhsT)); 3696 3697 // Attempt the assignment in an unevaluated context within a SFINAE 3698 // trap at translation unit scope. 3699 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3700 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3701 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3702 ExprResult Result = Self.BuildBinOp(/*S=*/0, KeyLoc, BO_Assign, &Lhs, &Rhs); 3703 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3704 return false; 3705 3706 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3707 // lifetime, this is a non-trivial assignment. 3708 if (Self.getLangOpts().ObjCAutoRefCount && 3709 hasNontrivialObjCLifetime(LhsT.getNonReferenceType())) 3710 return false; 3711 3712 return !Result.get()->hasNonTrivialCall(Self.Context); 3713 } 3714 } 3715 llvm_unreachable("Unknown type trait or not implemented"); 3716} 3717 3718ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3719 SourceLocation KWLoc, 3720 TypeSourceInfo *LhsTSInfo, 3721 TypeSourceInfo *RhsTSInfo, 3722 SourceLocation RParen) { 3723 QualType LhsT = LhsTSInfo->getType(); 3724 QualType RhsT = RhsTSInfo->getType(); 3725 3726 if (BTT == BTT_TypeCompatible) { 3727 if (getLangOpts().CPlusPlus) { 3728 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3729 << SourceRange(KWLoc, RParen); 3730 return ExprError(); 3731 } 3732 } 3733 3734 bool Value = false; 3735 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3736 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3737 3738 // Select trait result type. 3739 QualType ResultType; 3740 switch (BTT) { 3741 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3742 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3743 case BTT_IsSame: ResultType = Context.BoolTy; break; 3744 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3745 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3746 case BTT_IsTriviallyAssignable: ResultType = Context.BoolTy; 3747 } 3748 3749 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3750 RhsTSInfo, Value, RParen, 3751 ResultType)); 3752} 3753 3754ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3755 SourceLocation KWLoc, 3756 ParsedType Ty, 3757 Expr* DimExpr, 3758 SourceLocation RParen) { 3759 TypeSourceInfo *TSInfo; 3760 QualType T = GetTypeFromParser(Ty, &TSInfo); 3761 if (!TSInfo) 3762 TSInfo = Context.getTrivialTypeSourceInfo(T); 3763 3764 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3765} 3766 3767static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3768 QualType T, Expr *DimExpr, 3769 SourceLocation KeyLoc) { 3770 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3771 3772 switch(ATT) { 3773 case ATT_ArrayRank: 3774 if (T->isArrayType()) { 3775 unsigned Dim = 0; 3776 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3777 ++Dim; 3778 T = AT->getElementType(); 3779 } 3780 return Dim; 3781 } 3782 return 0; 3783 3784 case ATT_ArrayExtent: { 3785 llvm::APSInt Value; 3786 uint64_t Dim; 3787 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3788 diag::err_dimension_expr_not_constant_integer, 3789 false).isInvalid()) 3790 return 0; 3791 if (Value.isSigned() && Value.isNegative()) { 3792 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer) 3793 << DimExpr->getSourceRange(); 3794 return 0; 3795 } 3796 Dim = Value.getLimitedValue(); 3797 3798 if (T->isArrayType()) { 3799 unsigned D = 0; 3800 bool Matched = false; 3801 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3802 if (Dim == D) { 3803 Matched = true; 3804 break; 3805 } 3806 ++D; 3807 T = AT->getElementType(); 3808 } 3809 3810 if (Matched && T->isArrayType()) { 3811 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3812 return CAT->getSize().getLimitedValue(); 3813 } 3814 } 3815 return 0; 3816 } 3817 } 3818 llvm_unreachable("Unknown type trait or not implemented"); 3819} 3820 3821ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3822 SourceLocation KWLoc, 3823 TypeSourceInfo *TSInfo, 3824 Expr* DimExpr, 3825 SourceLocation RParen) { 3826 QualType T = TSInfo->getType(); 3827 3828 // FIXME: This should likely be tracked as an APInt to remove any host 3829 // assumptions about the width of size_t on the target. 3830 uint64_t Value = 0; 3831 if (!T->isDependentType()) 3832 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3833 3834 // While the specification for these traits from the Embarcadero C++ 3835 // compiler's documentation says the return type is 'unsigned int', Clang 3836 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3837 // compiler, there is no difference. On several other platforms this is an 3838 // important distinction. 3839 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3840 DimExpr, RParen, 3841 Context.getSizeType())); 3842} 3843 3844ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3845 SourceLocation KWLoc, 3846 Expr *Queried, 3847 SourceLocation RParen) { 3848 // If error parsing the expression, ignore. 3849 if (!Queried) 3850 return ExprError(); 3851 3852 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3853 3854 return Result; 3855} 3856 3857static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3858 switch (ET) { 3859 case ET_IsLValueExpr: return E->isLValue(); 3860 case ET_IsRValueExpr: return E->isRValue(); 3861 } 3862 llvm_unreachable("Expression trait not covered by switch"); 3863} 3864 3865ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3866 SourceLocation KWLoc, 3867 Expr *Queried, 3868 SourceLocation RParen) { 3869 if (Queried->isTypeDependent()) { 3870 // Delay type-checking for type-dependent expressions. 3871 } else if (Queried->getType()->isPlaceholderType()) { 3872 ExprResult PE = CheckPlaceholderExpr(Queried); 3873 if (PE.isInvalid()) return ExprError(); 3874 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3875 } 3876 3877 bool Value = EvaluateExpressionTrait(ET, Queried); 3878 3879 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3880 RParen, Context.BoolTy)); 3881} 3882 3883QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3884 ExprValueKind &VK, 3885 SourceLocation Loc, 3886 bool isIndirect) { 3887 assert(!LHS.get()->getType()->isPlaceholderType() && 3888 !RHS.get()->getType()->isPlaceholderType() && 3889 "placeholders should have been weeded out by now"); 3890 3891 // The LHS undergoes lvalue conversions if this is ->*. 3892 if (isIndirect) { 3893 LHS = DefaultLvalueConversion(LHS.take()); 3894 if (LHS.isInvalid()) return QualType(); 3895 } 3896 3897 // The RHS always undergoes lvalue conversions. 3898 RHS = DefaultLvalueConversion(RHS.take()); 3899 if (RHS.isInvalid()) return QualType(); 3900 3901 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3902 // C++ 5.5p2 3903 // The binary operator .* [p3: ->*] binds its second operand, which shall 3904 // be of type "pointer to member of T" (where T is a completely-defined 3905 // class type) [...] 3906 QualType RHSType = RHS.get()->getType(); 3907 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3908 if (!MemPtr) { 3909 Diag(Loc, diag::err_bad_memptr_rhs) 3910 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3911 return QualType(); 3912 } 3913 3914 QualType Class(MemPtr->getClass(), 0); 3915 3916 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3917 // member pointer points must be completely-defined. However, there is no 3918 // reason for this semantic distinction, and the rule is not enforced by 3919 // other compilers. Therefore, we do not check this property, as it is 3920 // likely to be considered a defect. 3921 3922 // C++ 5.5p2 3923 // [...] to its first operand, which shall be of class T or of a class of 3924 // which T is an unambiguous and accessible base class. [p3: a pointer to 3925 // such a class] 3926 QualType LHSType = LHS.get()->getType(); 3927 if (isIndirect) { 3928 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3929 LHSType = Ptr->getPointeeType(); 3930 else { 3931 Diag(Loc, diag::err_bad_memptr_lhs) 3932 << OpSpelling << 1 << LHSType 3933 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3934 return QualType(); 3935 } 3936 } 3937 3938 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3939 // If we want to check the hierarchy, we need a complete type. 3940 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs, 3941 OpSpelling, (int)isIndirect)) { 3942 return QualType(); 3943 } 3944 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3945 /*DetectVirtual=*/false); 3946 // FIXME: Would it be useful to print full ambiguity paths, or is that 3947 // overkill? 3948 if (!IsDerivedFrom(LHSType, Class, Paths) || 3949 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3950 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3951 << (int)isIndirect << LHS.get()->getType(); 3952 return QualType(); 3953 } 3954 // Cast LHS to type of use. 3955 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3956 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3957 3958 CXXCastPath BasePath; 3959 BuildBasePathArray(Paths, BasePath); 3960 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3961 &BasePath); 3962 } 3963 3964 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3965 // Diagnose use of pointer-to-member type which when used as 3966 // the functional cast in a pointer-to-member expression. 3967 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3968 return QualType(); 3969 } 3970 3971 // C++ 5.5p2 3972 // The result is an object or a function of the type specified by the 3973 // second operand. 3974 // The cv qualifiers are the union of those in the pointer and the left side, 3975 // in accordance with 5.5p5 and 5.2.5. 3976 QualType Result = MemPtr->getPointeeType(); 3977 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3978 3979 // C++0x [expr.mptr.oper]p6: 3980 // In a .* expression whose object expression is an rvalue, the program is 3981 // ill-formed if the second operand is a pointer to member function with 3982 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3983 // expression is an lvalue, the program is ill-formed if the second operand 3984 // is a pointer to member function with ref-qualifier &&. 3985 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3986 switch (Proto->getRefQualifier()) { 3987 case RQ_None: 3988 // Do nothing 3989 break; 3990 3991 case RQ_LValue: 3992 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3993 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3994 << RHSType << 1 << LHS.get()->getSourceRange(); 3995 break; 3996 3997 case RQ_RValue: 3998 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 3999 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 4000 << RHSType << 0 << LHS.get()->getSourceRange(); 4001 break; 4002 } 4003 } 4004 4005 // C++ [expr.mptr.oper]p6: 4006 // The result of a .* expression whose second operand is a pointer 4007 // to a data member is of the same value category as its 4008 // first operand. The result of a .* expression whose second 4009 // operand is a pointer to a member function is a prvalue. The 4010 // result of an ->* expression is an lvalue if its second operand 4011 // is a pointer to data member and a prvalue otherwise. 4012 if (Result->isFunctionType()) { 4013 VK = VK_RValue; 4014 return Context.BoundMemberTy; 4015 } else if (isIndirect) { 4016 VK = VK_LValue; 4017 } else { 4018 VK = LHS.get()->getValueKind(); 4019 } 4020 4021 return Result; 4022} 4023 4024/// \brief Try to convert a type to another according to C++0x 5.16p3. 4025/// 4026/// This is part of the parameter validation for the ? operator. If either 4027/// value operand is a class type, the two operands are attempted to be 4028/// converted to each other. This function does the conversion in one direction. 4029/// It returns true if the program is ill-formed and has already been diagnosed 4030/// as such. 4031static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 4032 SourceLocation QuestionLoc, 4033 bool &HaveConversion, 4034 QualType &ToType) { 4035 HaveConversion = false; 4036 ToType = To->getType(); 4037 4038 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 4039 SourceLocation()); 4040 // C++0x 5.16p3 4041 // The process for determining whether an operand expression E1 of type T1 4042 // can be converted to match an operand expression E2 of type T2 is defined 4043 // as follows: 4044 // -- If E2 is an lvalue: 4045 bool ToIsLvalue = To->isLValue(); 4046 if (ToIsLvalue) { 4047 // E1 can be converted to match E2 if E1 can be implicitly converted to 4048 // type "lvalue reference to T2", subject to the constraint that in the 4049 // conversion the reference must bind directly to E1. 4050 QualType T = Self.Context.getLValueReferenceType(ToType); 4051 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 4052 4053 InitializationSequence InitSeq(Self, Entity, Kind, From); 4054 if (InitSeq.isDirectReferenceBinding()) { 4055 ToType = T; 4056 HaveConversion = true; 4057 return false; 4058 } 4059 4060 if (InitSeq.isAmbiguous()) 4061 return InitSeq.Diagnose(Self, Entity, Kind, From); 4062 } 4063 4064 // -- If E2 is an rvalue, or if the conversion above cannot be done: 4065 // -- if E1 and E2 have class type, and the underlying class types are 4066 // the same or one is a base class of the other: 4067 QualType FTy = From->getType(); 4068 QualType TTy = To->getType(); 4069 const RecordType *FRec = FTy->getAs<RecordType>(); 4070 const RecordType *TRec = TTy->getAs<RecordType>(); 4071 bool FDerivedFromT = FRec && TRec && FRec != TRec && 4072 Self.IsDerivedFrom(FTy, TTy); 4073 if (FRec && TRec && 4074 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 4075 // E1 can be converted to match E2 if the class of T2 is the 4076 // same type as, or a base class of, the class of T1, and 4077 // [cv2 > cv1]. 4078 if (FRec == TRec || FDerivedFromT) { 4079 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 4080 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 4081 InitializationSequence InitSeq(Self, Entity, Kind, From); 4082 if (InitSeq) { 4083 HaveConversion = true; 4084 return false; 4085 } 4086 4087 if (InitSeq.isAmbiguous()) 4088 return InitSeq.Diagnose(Self, Entity, Kind, From); 4089 } 4090 } 4091 4092 return false; 4093 } 4094 4095 // -- Otherwise: E1 can be converted to match E2 if E1 can be 4096 // implicitly converted to the type that expression E2 would have 4097 // if E2 were converted to an rvalue (or the type it has, if E2 is 4098 // an rvalue). 4099 // 4100 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 4101 // to the array-to-pointer or function-to-pointer conversions. 4102 if (!TTy->getAs<TagType>()) 4103 TTy = TTy.getUnqualifiedType(); 4104 4105 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 4106 InitializationSequence InitSeq(Self, Entity, Kind, From); 4107 HaveConversion = !InitSeq.Failed(); 4108 ToType = TTy; 4109 if (InitSeq.isAmbiguous()) 4110 return InitSeq.Diagnose(Self, Entity, Kind, From); 4111 4112 return false; 4113} 4114 4115/// \brief Try to find a common type for two according to C++0x 5.16p5. 4116/// 4117/// This is part of the parameter validation for the ? operator. If either 4118/// value operand is a class type, overload resolution is used to find a 4119/// conversion to a common type. 4120static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 4121 SourceLocation QuestionLoc) { 4122 Expr *Args[2] = { LHS.get(), RHS.get() }; 4123 OverloadCandidateSet CandidateSet(QuestionLoc); 4124 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 4125 CandidateSet); 4126 4127 OverloadCandidateSet::iterator Best; 4128 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 4129 case OR_Success: { 4130 // We found a match. Perform the conversions on the arguments and move on. 4131 ExprResult LHSRes = 4132 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 4133 Best->Conversions[0], Sema::AA_Converting); 4134 if (LHSRes.isInvalid()) 4135 break; 4136 LHS = LHSRes; 4137 4138 ExprResult RHSRes = 4139 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 4140 Best->Conversions[1], Sema::AA_Converting); 4141 if (RHSRes.isInvalid()) 4142 break; 4143 RHS = RHSRes; 4144 if (Best->Function) 4145 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 4146 return false; 4147 } 4148 4149 case OR_No_Viable_Function: 4150 4151 // Emit a better diagnostic if one of the expressions is a null pointer 4152 // constant and the other is a pointer type. In this case, the user most 4153 // likely forgot to take the address of the other expression. 4154 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4155 return true; 4156 4157 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4158 << LHS.get()->getType() << RHS.get()->getType() 4159 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4160 return true; 4161 4162 case OR_Ambiguous: 4163 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 4164 << LHS.get()->getType() << RHS.get()->getType() 4165 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4166 // FIXME: Print the possible common types by printing the return types of 4167 // the viable candidates. 4168 break; 4169 4170 case OR_Deleted: 4171 llvm_unreachable("Conditional operator has only built-in overloads"); 4172 } 4173 return true; 4174} 4175 4176/// \brief Perform an "extended" implicit conversion as returned by 4177/// TryClassUnification. 4178static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 4179 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 4180 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 4181 SourceLocation()); 4182 Expr *Arg = E.take(); 4183 InitializationSequence InitSeq(Self, Entity, Kind, Arg); 4184 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg); 4185 if (Result.isInvalid()) 4186 return true; 4187 4188 E = Result; 4189 return false; 4190} 4191 4192/// \brief Check the operands of ?: under C++ semantics. 4193/// 4194/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 4195/// extension. In this case, LHS == Cond. (But they're not aliases.) 4196QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 4197 ExprResult &RHS, ExprValueKind &VK, 4198 ExprObjectKind &OK, 4199 SourceLocation QuestionLoc) { 4200 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 4201 // interface pointers. 4202 4203 // C++11 [expr.cond]p1 4204 // The first expression is contextually converted to bool. 4205 if (!Cond.get()->isTypeDependent()) { 4206 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 4207 if (CondRes.isInvalid()) 4208 return QualType(); 4209 Cond = CondRes; 4210 } 4211 4212 // Assume r-value. 4213 VK = VK_RValue; 4214 OK = OK_Ordinary; 4215 4216 // Either of the arguments dependent? 4217 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 4218 return Context.DependentTy; 4219 4220 // C++11 [expr.cond]p2 4221 // If either the second or the third operand has type (cv) void, ... 4222 QualType LTy = LHS.get()->getType(); 4223 QualType RTy = RHS.get()->getType(); 4224 bool LVoid = LTy->isVoidType(); 4225 bool RVoid = RTy->isVoidType(); 4226 if (LVoid || RVoid) { 4227 // ... then the [l2r] conversions are performed on the second and third 4228 // operands ... 4229 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4230 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4231 if (LHS.isInvalid() || RHS.isInvalid()) 4232 return QualType(); 4233 4234 // Finish off the lvalue-to-rvalue conversion by copy-initializing a 4235 // temporary if necessary. DefaultFunctionArrayLvalueConversion doesn't 4236 // do this part for us. 4237 ExprResult &NonVoid = LVoid ? RHS : LHS; 4238 if (NonVoid.get()->getType()->isRecordType() && 4239 NonVoid.get()->isGLValue()) { 4240 if (RequireNonAbstractType(QuestionLoc, NonVoid.get()->getType(), 4241 diag::err_allocation_of_abstract_type)) 4242 return QualType(); 4243 InitializedEntity Entity = 4244 InitializedEntity::InitializeTemporary(NonVoid.get()->getType()); 4245 NonVoid = PerformCopyInitialization(Entity, SourceLocation(), NonVoid); 4246 if (NonVoid.isInvalid()) 4247 return QualType(); 4248 } 4249 4250 LTy = LHS.get()->getType(); 4251 RTy = RHS.get()->getType(); 4252 4253 // ... and one of the following shall hold: 4254 // -- The second or the third operand (but not both) is a throw- 4255 // expression; the result is of the type of the other and is a prvalue. 4256 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 4257 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 4258 if (LThrow && !RThrow) 4259 return RTy; 4260 if (RThrow && !LThrow) 4261 return LTy; 4262 4263 // -- Both the second and third operands have type void; the result is of 4264 // type void and is a prvalue. 4265 if (LVoid && RVoid) 4266 return Context.VoidTy; 4267 4268 // Neither holds, error. 4269 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 4270 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 4271 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4272 return QualType(); 4273 } 4274 4275 // Neither is void. 4276 4277 // C++11 [expr.cond]p3 4278 // Otherwise, if the second and third operand have different types, and 4279 // either has (cv) class type [...] an attempt is made to convert each of 4280 // those operands to the type of the other. 4281 if (!Context.hasSameType(LTy, RTy) && 4282 (LTy->isRecordType() || RTy->isRecordType())) { 4283 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 4284 // These return true if a single direction is already ambiguous. 4285 QualType L2RType, R2LType; 4286 bool HaveL2R, HaveR2L; 4287 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 4288 return QualType(); 4289 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 4290 return QualType(); 4291 4292 // If both can be converted, [...] the program is ill-formed. 4293 if (HaveL2R && HaveR2L) { 4294 Diag(QuestionLoc, diag::err_conditional_ambiguous) 4295 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4296 return QualType(); 4297 } 4298 4299 // If exactly one conversion is possible, that conversion is applied to 4300 // the chosen operand and the converted operands are used in place of the 4301 // original operands for the remainder of this section. 4302 if (HaveL2R) { 4303 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 4304 return QualType(); 4305 LTy = LHS.get()->getType(); 4306 } else if (HaveR2L) { 4307 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 4308 return QualType(); 4309 RTy = RHS.get()->getType(); 4310 } 4311 } 4312 4313 // C++11 [expr.cond]p3 4314 // if both are glvalues of the same value category and the same type except 4315 // for cv-qualification, an attempt is made to convert each of those 4316 // operands to the type of the other. 4317 ExprValueKind LVK = LHS.get()->getValueKind(); 4318 ExprValueKind RVK = RHS.get()->getValueKind(); 4319 if (!Context.hasSameType(LTy, RTy) && 4320 Context.hasSameUnqualifiedType(LTy, RTy) && 4321 LVK == RVK && LVK != VK_RValue) { 4322 // Since the unqualified types are reference-related and we require the 4323 // result to be as if a reference bound directly, the only conversion 4324 // we can perform is to add cv-qualifiers. 4325 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers()); 4326 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers()); 4327 if (RCVR.isStrictSupersetOf(LCVR)) { 4328 LHS = ImpCastExprToType(LHS.take(), RTy, CK_NoOp, LVK); 4329 LTy = LHS.get()->getType(); 4330 } 4331 else if (LCVR.isStrictSupersetOf(RCVR)) { 4332 RHS = ImpCastExprToType(RHS.take(), LTy, CK_NoOp, RVK); 4333 RTy = RHS.get()->getType(); 4334 } 4335 } 4336 4337 // C++11 [expr.cond]p4 4338 // If the second and third operands are glvalues of the same value 4339 // category and have the same type, the result is of that type and 4340 // value category and it is a bit-field if the second or the third 4341 // operand is a bit-field, or if both are bit-fields. 4342 // We only extend this to bitfields, not to the crazy other kinds of 4343 // l-values. 4344 bool Same = Context.hasSameType(LTy, RTy); 4345 if (Same && LVK == RVK && LVK != VK_RValue && 4346 LHS.get()->isOrdinaryOrBitFieldObject() && 4347 RHS.get()->isOrdinaryOrBitFieldObject()) { 4348 VK = LHS.get()->getValueKind(); 4349 if (LHS.get()->getObjectKind() == OK_BitField || 4350 RHS.get()->getObjectKind() == OK_BitField) 4351 OK = OK_BitField; 4352 return LTy; 4353 } 4354 4355 // C++11 [expr.cond]p5 4356 // Otherwise, the result is a prvalue. If the second and third operands 4357 // do not have the same type, and either has (cv) class type, ... 4358 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 4359 // ... overload resolution is used to determine the conversions (if any) 4360 // to be applied to the operands. If the overload resolution fails, the 4361 // program is ill-formed. 4362 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 4363 return QualType(); 4364 } 4365 4366 // C++11 [expr.cond]p6 4367 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard 4368 // conversions are performed on the second and third operands. 4369 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4370 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4371 if (LHS.isInvalid() || RHS.isInvalid()) 4372 return QualType(); 4373 LTy = LHS.get()->getType(); 4374 RTy = RHS.get()->getType(); 4375 4376 // After those conversions, one of the following shall hold: 4377 // -- The second and third operands have the same type; the result 4378 // is of that type. If the operands have class type, the result 4379 // is a prvalue temporary of the result type, which is 4380 // copy-initialized from either the second operand or the third 4381 // operand depending on the value of the first operand. 4382 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 4383 if (LTy->isRecordType()) { 4384 // The operands have class type. Make a temporary copy. 4385 if (RequireNonAbstractType(QuestionLoc, LTy, 4386 diag::err_allocation_of_abstract_type)) 4387 return QualType(); 4388 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 4389 4390 ExprResult LHSCopy = PerformCopyInitialization(Entity, 4391 SourceLocation(), 4392 LHS); 4393 if (LHSCopy.isInvalid()) 4394 return QualType(); 4395 4396 ExprResult RHSCopy = PerformCopyInitialization(Entity, 4397 SourceLocation(), 4398 RHS); 4399 if (RHSCopy.isInvalid()) 4400 return QualType(); 4401 4402 LHS = LHSCopy; 4403 RHS = RHSCopy; 4404 } 4405 4406 return LTy; 4407 } 4408 4409 // Extension: conditional operator involving vector types. 4410 if (LTy->isVectorType() || RTy->isVectorType()) 4411 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4412 4413 // -- The second and third operands have arithmetic or enumeration type; 4414 // the usual arithmetic conversions are performed to bring them to a 4415 // common type, and the result is of that type. 4416 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 4417 UsualArithmeticConversions(LHS, RHS); 4418 if (LHS.isInvalid() || RHS.isInvalid()) 4419 return QualType(); 4420 return LHS.get()->getType(); 4421 } 4422 4423 // -- The second and third operands have pointer type, or one has pointer 4424 // type and the other is a null pointer constant, or both are null 4425 // pointer constants, at least one of which is non-integral; pointer 4426 // conversions and qualification conversions are performed to bring them 4427 // to their composite pointer type. The result is of the composite 4428 // pointer type. 4429 // -- The second and third operands have pointer to member type, or one has 4430 // pointer to member type and the other is a null pointer constant; 4431 // pointer to member conversions and qualification conversions are 4432 // performed to bring them to a common type, whose cv-qualification 4433 // shall match the cv-qualification of either the second or the third 4434 // operand. The result is of the common type. 4435 bool NonStandardCompositeType = false; 4436 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 4437 isSFINAEContext()? 0 : &NonStandardCompositeType); 4438 if (!Composite.isNull()) { 4439 if (NonStandardCompositeType) 4440 Diag(QuestionLoc, 4441 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 4442 << LTy << RTy << Composite 4443 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4444 4445 return Composite; 4446 } 4447 4448 // Similarly, attempt to find composite type of two objective-c pointers. 4449 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 4450 if (!Composite.isNull()) 4451 return Composite; 4452 4453 // Check if we are using a null with a non-pointer type. 4454 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4455 return QualType(); 4456 4457 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4458 << LHS.get()->getType() << RHS.get()->getType() 4459 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4460 return QualType(); 4461} 4462 4463/// \brief Find a merged pointer type and convert the two expressions to it. 4464/// 4465/// This finds the composite pointer type (or member pointer type) for @p E1 4466/// and @p E2 according to C++11 5.9p2. It converts both expressions to this 4467/// type and returns it. 4468/// It does not emit diagnostics. 4469/// 4470/// \param Loc The location of the operator requiring these two expressions to 4471/// be converted to the composite pointer type. 4472/// 4473/// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4474/// a non-standard (but still sane) composite type to which both expressions 4475/// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4476/// will be set true. 4477QualType Sema::FindCompositePointerType(SourceLocation Loc, 4478 Expr *&E1, Expr *&E2, 4479 bool *NonStandardCompositeType) { 4480 if (NonStandardCompositeType) 4481 *NonStandardCompositeType = false; 4482 4483 assert(getLangOpts().CPlusPlus && "This function assumes C++"); 4484 QualType T1 = E1->getType(), T2 = E2->getType(); 4485 4486 // C++11 5.9p2 4487 // Pointer conversions and qualification conversions are performed on 4488 // pointer operands to bring them to their composite pointer type. If 4489 // one operand is a null pointer constant, the composite pointer type is 4490 // std::nullptr_t if the other operand is also a null pointer constant or, 4491 // if the other operand is a pointer, the type of the other operand. 4492 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4493 !T2->isAnyPointerType() && !T2->isMemberPointerType()) { 4494 if (T1->isNullPtrType() && 4495 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4496 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4497 return T1; 4498 } 4499 if (T2->isNullPtrType() && 4500 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4501 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4502 return T2; 4503 } 4504 return QualType(); 4505 } 4506 4507 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4508 if (T2->isMemberPointerType()) 4509 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4510 else 4511 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4512 return T2; 4513 } 4514 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4515 if (T1->isMemberPointerType()) 4516 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4517 else 4518 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4519 return T1; 4520 } 4521 4522 // Now both have to be pointers or member pointers. 4523 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4524 (!T2->isPointerType() && !T2->isMemberPointerType())) 4525 return QualType(); 4526 4527 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4528 // the other has type "pointer to cv2 T" and the composite pointer type is 4529 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4530 // Otherwise, the composite pointer type is a pointer type similar to the 4531 // type of one of the operands, with a cv-qualification signature that is 4532 // the union of the cv-qualification signatures of the operand types. 4533 // In practice, the first part here is redundant; it's subsumed by the second. 4534 // What we do here is, we build the two possible composite types, and try the 4535 // conversions in both directions. If only one works, or if the two composite 4536 // types are the same, we have succeeded. 4537 // FIXME: extended qualifiers? 4538 typedef SmallVector<unsigned, 4> QualifierVector; 4539 QualifierVector QualifierUnion; 4540 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4541 ContainingClassVector; 4542 ContainingClassVector MemberOfClass; 4543 QualType Composite1 = Context.getCanonicalType(T1), 4544 Composite2 = Context.getCanonicalType(T2); 4545 unsigned NeedConstBefore = 0; 4546 do { 4547 const PointerType *Ptr1, *Ptr2; 4548 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4549 (Ptr2 = Composite2->getAs<PointerType>())) { 4550 Composite1 = Ptr1->getPointeeType(); 4551 Composite2 = Ptr2->getPointeeType(); 4552 4553 // If we're allowed to create a non-standard composite type, keep track 4554 // of where we need to fill in additional 'const' qualifiers. 4555 if (NonStandardCompositeType && 4556 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4557 NeedConstBefore = QualifierUnion.size(); 4558 4559 QualifierUnion.push_back( 4560 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4561 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4562 continue; 4563 } 4564 4565 const MemberPointerType *MemPtr1, *MemPtr2; 4566 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4567 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4568 Composite1 = MemPtr1->getPointeeType(); 4569 Composite2 = MemPtr2->getPointeeType(); 4570 4571 // If we're allowed to create a non-standard composite type, keep track 4572 // of where we need to fill in additional 'const' qualifiers. 4573 if (NonStandardCompositeType && 4574 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4575 NeedConstBefore = QualifierUnion.size(); 4576 4577 QualifierUnion.push_back( 4578 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4579 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4580 MemPtr2->getClass())); 4581 continue; 4582 } 4583 4584 // FIXME: block pointer types? 4585 4586 // Cannot unwrap any more types. 4587 break; 4588 } while (true); 4589 4590 if (NeedConstBefore && NonStandardCompositeType) { 4591 // Extension: Add 'const' to qualifiers that come before the first qualifier 4592 // mismatch, so that our (non-standard!) composite type meets the 4593 // requirements of C++ [conv.qual]p4 bullet 3. 4594 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4595 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4596 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4597 *NonStandardCompositeType = true; 4598 } 4599 } 4600 } 4601 4602 // Rewrap the composites as pointers or member pointers with the union CVRs. 4603 ContainingClassVector::reverse_iterator MOC 4604 = MemberOfClass.rbegin(); 4605 for (QualifierVector::reverse_iterator 4606 I = QualifierUnion.rbegin(), 4607 E = QualifierUnion.rend(); 4608 I != E; (void)++I, ++MOC) { 4609 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4610 if (MOC->first && MOC->second) { 4611 // Rebuild member pointer type 4612 Composite1 = Context.getMemberPointerType( 4613 Context.getQualifiedType(Composite1, Quals), 4614 MOC->first); 4615 Composite2 = Context.getMemberPointerType( 4616 Context.getQualifiedType(Composite2, Quals), 4617 MOC->second); 4618 } else { 4619 // Rebuild pointer type 4620 Composite1 4621 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4622 Composite2 4623 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4624 } 4625 } 4626 4627 // Try to convert to the first composite pointer type. 4628 InitializedEntity Entity1 4629 = InitializedEntity::InitializeTemporary(Composite1); 4630 InitializationKind Kind 4631 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4632 InitializationSequence E1ToC1(*this, Entity1, Kind, E1); 4633 InitializationSequence E2ToC1(*this, Entity1, Kind, E2); 4634 4635 if (E1ToC1 && E2ToC1) { 4636 // Conversion to Composite1 is viable. 4637 if (!Context.hasSameType(Composite1, Composite2)) { 4638 // Composite2 is a different type from Composite1. Check whether 4639 // Composite2 is also viable. 4640 InitializedEntity Entity2 4641 = InitializedEntity::InitializeTemporary(Composite2); 4642 InitializationSequence E1ToC2(*this, Entity2, Kind, E1); 4643 InitializationSequence E2ToC2(*this, Entity2, Kind, E2); 4644 if (E1ToC2 && E2ToC2) { 4645 // Both Composite1 and Composite2 are viable and are different; 4646 // this is an ambiguity. 4647 return QualType(); 4648 } 4649 } 4650 4651 // Convert E1 to Composite1 4652 ExprResult E1Result 4653 = E1ToC1.Perform(*this, Entity1, Kind, E1); 4654 if (E1Result.isInvalid()) 4655 return QualType(); 4656 E1 = E1Result.takeAs<Expr>(); 4657 4658 // Convert E2 to Composite1 4659 ExprResult E2Result 4660 = E2ToC1.Perform(*this, Entity1, Kind, E2); 4661 if (E2Result.isInvalid()) 4662 return QualType(); 4663 E2 = E2Result.takeAs<Expr>(); 4664 4665 return Composite1; 4666 } 4667 4668 // Check whether Composite2 is viable. 4669 InitializedEntity Entity2 4670 = InitializedEntity::InitializeTemporary(Composite2); 4671 InitializationSequence E1ToC2(*this, Entity2, Kind, E1); 4672 InitializationSequence E2ToC2(*this, Entity2, Kind, E2); 4673 if (!E1ToC2 || !E2ToC2) 4674 return QualType(); 4675 4676 // Convert E1 to Composite2 4677 ExprResult E1Result 4678 = E1ToC2.Perform(*this, Entity2, Kind, E1); 4679 if (E1Result.isInvalid()) 4680 return QualType(); 4681 E1 = E1Result.takeAs<Expr>(); 4682 4683 // Convert E2 to Composite2 4684 ExprResult E2Result 4685 = E2ToC2.Perform(*this, Entity2, Kind, E2); 4686 if (E2Result.isInvalid()) 4687 return QualType(); 4688 E2 = E2Result.takeAs<Expr>(); 4689 4690 return Composite2; 4691} 4692 4693ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4694 if (!E) 4695 return ExprError(); 4696 4697 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4698 4699 // If the result is a glvalue, we shouldn't bind it. 4700 if (!E->isRValue()) 4701 return Owned(E); 4702 4703 // In ARC, calls that return a retainable type can return retained, 4704 // in which case we have to insert a consuming cast. 4705 if (getLangOpts().ObjCAutoRefCount && 4706 E->getType()->isObjCRetainableType()) { 4707 4708 bool ReturnsRetained; 4709 4710 // For actual calls, we compute this by examining the type of the 4711 // called value. 4712 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4713 Expr *Callee = Call->getCallee()->IgnoreParens(); 4714 QualType T = Callee->getType(); 4715 4716 if (T == Context.BoundMemberTy) { 4717 // Handle pointer-to-members. 4718 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4719 T = BinOp->getRHS()->getType(); 4720 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4721 T = Mem->getMemberDecl()->getType(); 4722 } 4723 4724 if (const PointerType *Ptr = T->getAs<PointerType>()) 4725 T = Ptr->getPointeeType(); 4726 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4727 T = Ptr->getPointeeType(); 4728 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4729 T = MemPtr->getPointeeType(); 4730 4731 const FunctionType *FTy = T->getAs<FunctionType>(); 4732 assert(FTy && "call to value not of function type?"); 4733 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4734 4735 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4736 // type always produce a +1 object. 4737 } else if (isa<StmtExpr>(E)) { 4738 ReturnsRetained = true; 4739 4740 // We hit this case with the lambda conversion-to-block optimization; 4741 // we don't want any extra casts here. 4742 } else if (isa<CastExpr>(E) && 4743 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) { 4744 return Owned(E); 4745 4746 // For message sends and property references, we try to find an 4747 // actual method. FIXME: we should infer retention by selector in 4748 // cases where we don't have an actual method. 4749 } else { 4750 ObjCMethodDecl *D = 0; 4751 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4752 D = Send->getMethodDecl(); 4753 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) { 4754 D = BoxedExpr->getBoxingMethod(); 4755 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) { 4756 D = ArrayLit->getArrayWithObjectsMethod(); 4757 } else if (ObjCDictionaryLiteral *DictLit 4758 = dyn_cast<ObjCDictionaryLiteral>(E)) { 4759 D = DictLit->getDictWithObjectsMethod(); 4760 } 4761 4762 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4763 4764 // Don't do reclaims on performSelector calls; despite their 4765 // return type, the invoked method doesn't necessarily actually 4766 // return an object. 4767 if (!ReturnsRetained && 4768 D && D->getMethodFamily() == OMF_performSelector) 4769 return Owned(E); 4770 } 4771 4772 // Don't reclaim an object of Class type. 4773 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4774 return Owned(E); 4775 4776 ExprNeedsCleanups = true; 4777 4778 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4779 : CK_ARCReclaimReturnedObject); 4780 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4781 VK_RValue)); 4782 } 4783 4784 if (!getLangOpts().CPlusPlus) 4785 return Owned(E); 4786 4787 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4788 // a fast path for the common case that the type is directly a RecordType. 4789 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4790 const RecordType *RT = 0; 4791 while (!RT) { 4792 switch (T->getTypeClass()) { 4793 case Type::Record: 4794 RT = cast<RecordType>(T); 4795 break; 4796 case Type::ConstantArray: 4797 case Type::IncompleteArray: 4798 case Type::VariableArray: 4799 case Type::DependentSizedArray: 4800 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4801 break; 4802 default: 4803 return Owned(E); 4804 } 4805 } 4806 4807 // That should be enough to guarantee that this type is complete, if we're 4808 // not processing a decltype expression. 4809 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4810 if (RD->isInvalidDecl() || RD->isDependentContext()) 4811 return Owned(E); 4812 4813 bool IsDecltype = ExprEvalContexts.back().IsDecltype; 4814 CXXDestructorDecl *Destructor = IsDecltype ? 0 : LookupDestructor(RD); 4815 4816 if (Destructor) { 4817 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4818 CheckDestructorAccess(E->getExprLoc(), Destructor, 4819 PDiag(diag::err_access_dtor_temp) 4820 << E->getType()); 4821 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc())) 4822 return ExprError(); 4823 4824 // If destructor is trivial, we can avoid the extra copy. 4825 if (Destructor->isTrivial()) 4826 return Owned(E); 4827 4828 // We need a cleanup, but we don't need to remember the temporary. 4829 ExprNeedsCleanups = true; 4830 } 4831 4832 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4833 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E); 4834 4835 if (IsDecltype) 4836 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind); 4837 4838 return Owned(Bind); 4839} 4840 4841ExprResult 4842Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4843 if (SubExpr.isInvalid()) 4844 return ExprError(); 4845 4846 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4847} 4848 4849Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4850 assert(SubExpr && "sub expression can't be null!"); 4851 4852 CleanupVarDeclMarking(); 4853 4854 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4855 assert(ExprCleanupObjects.size() >= FirstCleanup); 4856 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4857 if (!ExprNeedsCleanups) 4858 return SubExpr; 4859 4860 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4861 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4862 ExprCleanupObjects.size() - FirstCleanup); 4863 4864 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4865 DiscardCleanupsInEvaluationContext(); 4866 4867 return E; 4868} 4869 4870Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4871 assert(SubStmt && "sub statement can't be null!"); 4872 4873 CleanupVarDeclMarking(); 4874 4875 if (!ExprNeedsCleanups) 4876 return SubStmt; 4877 4878 // FIXME: In order to attach the temporaries, wrap the statement into 4879 // a StmtExpr; currently this is only used for asm statements. 4880 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4881 // a new AsmStmtWithTemporaries. 4882 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt, 4883 SourceLocation(), 4884 SourceLocation()); 4885 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4886 SourceLocation()); 4887 return MaybeCreateExprWithCleanups(E); 4888} 4889 4890/// Process the expression contained within a decltype. For such expressions, 4891/// certain semantic checks on temporaries are delayed until this point, and 4892/// are omitted for the 'topmost' call in the decltype expression. If the 4893/// topmost call bound a temporary, strip that temporary off the expression. 4894ExprResult Sema::ActOnDecltypeExpression(Expr *E) { 4895 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression"); 4896 4897 // C++11 [expr.call]p11: 4898 // If a function call is a prvalue of object type, 4899 // -- if the function call is either 4900 // -- the operand of a decltype-specifier, or 4901 // -- the right operand of a comma operator that is the operand of a 4902 // decltype-specifier, 4903 // a temporary object is not introduced for the prvalue. 4904 4905 // Recursively rebuild ParenExprs and comma expressions to strip out the 4906 // outermost CXXBindTemporaryExpr, if any. 4907 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 4908 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr()); 4909 if (SubExpr.isInvalid()) 4910 return ExprError(); 4911 if (SubExpr.get() == PE->getSubExpr()) 4912 return Owned(E); 4913 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.take()); 4914 } 4915 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 4916 if (BO->getOpcode() == BO_Comma) { 4917 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS()); 4918 if (RHS.isInvalid()) 4919 return ExprError(); 4920 if (RHS.get() == BO->getRHS()) 4921 return Owned(E); 4922 return Owned(new (Context) BinaryOperator(BO->getLHS(), RHS.take(), 4923 BO_Comma, BO->getType(), 4924 BO->getValueKind(), 4925 BO->getObjectKind(), 4926 BO->getOperatorLoc(), 4927 BO->isFPContractable())); 4928 } 4929 } 4930 4931 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E); 4932 if (TopBind) 4933 E = TopBind->getSubExpr(); 4934 4935 // Disable the special decltype handling now. 4936 ExprEvalContexts.back().IsDecltype = false; 4937 4938 // In MS mode, don't perform any extra checking of call return types within a 4939 // decltype expression. 4940 if (getLangOpts().MicrosoftMode) 4941 return Owned(E); 4942 4943 // Perform the semantic checks we delayed until this point. 4944 CallExpr *TopCall = dyn_cast<CallExpr>(E); 4945 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size(); 4946 I != N; ++I) { 4947 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I]; 4948 if (Call == TopCall) 4949 continue; 4950 4951 if (CheckCallReturnType(Call->getCallReturnType(), 4952 Call->getLocStart(), 4953 Call, Call->getDirectCallee())) 4954 return ExprError(); 4955 } 4956 4957 // Now all relevant types are complete, check the destructors are accessible 4958 // and non-deleted, and annotate them on the temporaries. 4959 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size(); 4960 I != N; ++I) { 4961 CXXBindTemporaryExpr *Bind = 4962 ExprEvalContexts.back().DelayedDecltypeBinds[I]; 4963 if (Bind == TopBind) 4964 continue; 4965 4966 CXXTemporary *Temp = Bind->getTemporary(); 4967 4968 CXXRecordDecl *RD = 4969 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 4970 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4971 Temp->setDestructor(Destructor); 4972 4973 MarkFunctionReferenced(Bind->getExprLoc(), Destructor); 4974 CheckDestructorAccess(Bind->getExprLoc(), Destructor, 4975 PDiag(diag::err_access_dtor_temp) 4976 << Bind->getType()); 4977 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc())) 4978 return ExprError(); 4979 4980 // We need a cleanup, but we don't need to remember the temporary. 4981 ExprNeedsCleanups = true; 4982 } 4983 4984 // Possibly strip off the top CXXBindTemporaryExpr. 4985 return Owned(E); 4986} 4987 4988ExprResult 4989Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4990 tok::TokenKind OpKind, ParsedType &ObjectType, 4991 bool &MayBePseudoDestructor) { 4992 // Since this might be a postfix expression, get rid of ParenListExprs. 4993 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4994 if (Result.isInvalid()) return ExprError(); 4995 Base = Result.get(); 4996 4997 Result = CheckPlaceholderExpr(Base); 4998 if (Result.isInvalid()) return ExprError(); 4999 Base = Result.take(); 5000 5001 QualType BaseType = Base->getType(); 5002 MayBePseudoDestructor = false; 5003 if (BaseType->isDependentType()) { 5004 // If we have a pointer to a dependent type and are using the -> operator, 5005 // the object type is the type that the pointer points to. We might still 5006 // have enough information about that type to do something useful. 5007 if (OpKind == tok::arrow) 5008 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 5009 BaseType = Ptr->getPointeeType(); 5010 5011 ObjectType = ParsedType::make(BaseType); 5012 MayBePseudoDestructor = true; 5013 return Owned(Base); 5014 } 5015 5016 // C++ [over.match.oper]p8: 5017 // [...] When operator->returns, the operator-> is applied to the value 5018 // returned, with the original second operand. 5019 if (OpKind == tok::arrow) { 5020 // The set of types we've considered so far. 5021 llvm::SmallPtrSet<CanQualType,8> CTypes; 5022 SmallVector<SourceLocation, 8> Locations; 5023 CTypes.insert(Context.getCanonicalType(BaseType)); 5024 5025 while (BaseType->isRecordType()) { 5026 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 5027 if (Result.isInvalid()) 5028 return ExprError(); 5029 Base = Result.get(); 5030 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 5031 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 5032 BaseType = Base->getType(); 5033 CanQualType CBaseType = Context.getCanonicalType(BaseType); 5034 if (!CTypes.insert(CBaseType)) { 5035 Diag(OpLoc, diag::err_operator_arrow_circular); 5036 for (unsigned i = 0; i < Locations.size(); i++) 5037 Diag(Locations[i], diag::note_declared_at); 5038 return ExprError(); 5039 } 5040 } 5041 5042 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 5043 BaseType = BaseType->getPointeeType(); 5044 } 5045 5046 // Objective-C properties allow "." access on Objective-C pointer types, 5047 // so adjust the base type to the object type itself. 5048 if (BaseType->isObjCObjectPointerType()) 5049 BaseType = BaseType->getPointeeType(); 5050 5051 // C++ [basic.lookup.classref]p2: 5052 // [...] If the type of the object expression is of pointer to scalar 5053 // type, the unqualified-id is looked up in the context of the complete 5054 // postfix-expression. 5055 // 5056 // This also indicates that we could be parsing a pseudo-destructor-name. 5057 // Note that Objective-C class and object types can be pseudo-destructor 5058 // expressions or normal member (ivar or property) access expressions. 5059 if (BaseType->isObjCObjectOrInterfaceType()) { 5060 MayBePseudoDestructor = true; 5061 } else if (!BaseType->isRecordType()) { 5062 ObjectType = ParsedType(); 5063 MayBePseudoDestructor = true; 5064 return Owned(Base); 5065 } 5066 5067 // The object type must be complete (or dependent), or 5068 // C++11 [expr.prim.general]p3: 5069 // Unlike the object expression in other contexts, *this is not required to 5070 // be of complete type for purposes of class member access (5.2.5) outside 5071 // the member function body. 5072 if (!BaseType->isDependentType() && 5073 !isThisOutsideMemberFunctionBody(BaseType) && 5074 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access)) 5075 return ExprError(); 5076 5077 // C++ [basic.lookup.classref]p2: 5078 // If the id-expression in a class member access (5.2.5) is an 5079 // unqualified-id, and the type of the object expression is of a class 5080 // type C (or of pointer to a class type C), the unqualified-id is looked 5081 // up in the scope of class C. [...] 5082 ObjectType = ParsedType::make(BaseType); 5083 return Base; 5084} 5085 5086ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 5087 Expr *MemExpr) { 5088 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 5089 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 5090 << isa<CXXPseudoDestructorExpr>(MemExpr) 5091 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 5092 5093 return ActOnCallExpr(/*Scope*/ 0, 5094 MemExpr, 5095 /*LPLoc*/ ExpectedLParenLoc, 5096 None, 5097 /*RPLoc*/ ExpectedLParenLoc); 5098} 5099 5100static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 5101 tok::TokenKind& OpKind, SourceLocation OpLoc) { 5102 if (Base->hasPlaceholderType()) { 5103 ExprResult result = S.CheckPlaceholderExpr(Base); 5104 if (result.isInvalid()) return true; 5105 Base = result.take(); 5106 } 5107 ObjectType = Base->getType(); 5108 5109 // C++ [expr.pseudo]p2: 5110 // The left-hand side of the dot operator shall be of scalar type. The 5111 // left-hand side of the arrow operator shall be of pointer to scalar type. 5112 // This scalar type is the object type. 5113 // Note that this is rather different from the normal handling for the 5114 // arrow operator. 5115 if (OpKind == tok::arrow) { 5116 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 5117 ObjectType = Ptr->getPointeeType(); 5118 } else if (!Base->isTypeDependent()) { 5119 // The user wrote "p->" when she probably meant "p."; fix it. 5120 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 5121 << ObjectType << true 5122 << FixItHint::CreateReplacement(OpLoc, "."); 5123 if (S.isSFINAEContext()) 5124 return true; 5125 5126 OpKind = tok::period; 5127 } 5128 } 5129 5130 return false; 5131} 5132 5133ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 5134 SourceLocation OpLoc, 5135 tok::TokenKind OpKind, 5136 const CXXScopeSpec &SS, 5137 TypeSourceInfo *ScopeTypeInfo, 5138 SourceLocation CCLoc, 5139 SourceLocation TildeLoc, 5140 PseudoDestructorTypeStorage Destructed, 5141 bool HasTrailingLParen) { 5142 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 5143 5144 QualType ObjectType; 5145 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5146 return ExprError(); 5147 5148 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() && 5149 !ObjectType->isVectorType()) { 5150 if (getLangOpts().MicrosoftMode && ObjectType->isVoidType()) 5151 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 5152 else 5153 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 5154 << ObjectType << Base->getSourceRange(); 5155 return ExprError(); 5156 } 5157 5158 // C++ [expr.pseudo]p2: 5159 // [...] The cv-unqualified versions of the object type and of the type 5160 // designated by the pseudo-destructor-name shall be the same type. 5161 if (DestructedTypeInfo) { 5162 QualType DestructedType = DestructedTypeInfo->getType(); 5163 SourceLocation DestructedTypeStart 5164 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 5165 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 5166 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 5167 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 5168 << ObjectType << DestructedType << Base->getSourceRange() 5169 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5170 5171 // Recover by setting the destructed type to the object type. 5172 DestructedType = ObjectType; 5173 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5174 DestructedTypeStart); 5175 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5176 } else if (DestructedType.getObjCLifetime() != 5177 ObjectType.getObjCLifetime()) { 5178 5179 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 5180 // Okay: just pretend that the user provided the correctly-qualified 5181 // type. 5182 } else { 5183 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 5184 << ObjectType << DestructedType << Base->getSourceRange() 5185 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5186 } 5187 5188 // Recover by setting the destructed type to the object type. 5189 DestructedType = ObjectType; 5190 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5191 DestructedTypeStart); 5192 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5193 } 5194 } 5195 } 5196 5197 // C++ [expr.pseudo]p2: 5198 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 5199 // form 5200 // 5201 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 5202 // 5203 // shall designate the same scalar type. 5204 if (ScopeTypeInfo) { 5205 QualType ScopeType = ScopeTypeInfo->getType(); 5206 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 5207 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 5208 5209 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 5210 diag::err_pseudo_dtor_type_mismatch) 5211 << ObjectType << ScopeType << Base->getSourceRange() 5212 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 5213 5214 ScopeType = QualType(); 5215 ScopeTypeInfo = 0; 5216 } 5217 } 5218 5219 Expr *Result 5220 = new (Context) CXXPseudoDestructorExpr(Context, Base, 5221 OpKind == tok::arrow, OpLoc, 5222 SS.getWithLocInContext(Context), 5223 ScopeTypeInfo, 5224 CCLoc, 5225 TildeLoc, 5226 Destructed); 5227 5228 if (HasTrailingLParen) 5229 return Owned(Result); 5230 5231 return DiagnoseDtorReference(Destructed.getLocation(), Result); 5232} 5233 5234ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5235 SourceLocation OpLoc, 5236 tok::TokenKind OpKind, 5237 CXXScopeSpec &SS, 5238 UnqualifiedId &FirstTypeName, 5239 SourceLocation CCLoc, 5240 SourceLocation TildeLoc, 5241 UnqualifiedId &SecondTypeName, 5242 bool HasTrailingLParen) { 5243 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5244 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5245 "Invalid first type name in pseudo-destructor"); 5246 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5247 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5248 "Invalid second type name in pseudo-destructor"); 5249 5250 QualType ObjectType; 5251 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5252 return ExprError(); 5253 5254 // Compute the object type that we should use for name lookup purposes. Only 5255 // record types and dependent types matter. 5256 ParsedType ObjectTypePtrForLookup; 5257 if (!SS.isSet()) { 5258 if (ObjectType->isRecordType()) 5259 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 5260 else if (ObjectType->isDependentType()) 5261 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 5262 } 5263 5264 // Convert the name of the type being destructed (following the ~) into a 5265 // type (with source-location information). 5266 QualType DestructedType; 5267 TypeSourceInfo *DestructedTypeInfo = 0; 5268 PseudoDestructorTypeStorage Destructed; 5269 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5270 ParsedType T = getTypeName(*SecondTypeName.Identifier, 5271 SecondTypeName.StartLocation, 5272 S, &SS, true, false, ObjectTypePtrForLookup); 5273 if (!T && 5274 ((SS.isSet() && !computeDeclContext(SS, false)) || 5275 (!SS.isSet() && ObjectType->isDependentType()))) { 5276 // The name of the type being destroyed is a dependent name, and we 5277 // couldn't find anything useful in scope. Just store the identifier and 5278 // it's location, and we'll perform (qualified) name lookup again at 5279 // template instantiation time. 5280 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 5281 SecondTypeName.StartLocation); 5282 } else if (!T) { 5283 Diag(SecondTypeName.StartLocation, 5284 diag::err_pseudo_dtor_destructor_non_type) 5285 << SecondTypeName.Identifier << ObjectType; 5286 if (isSFINAEContext()) 5287 return ExprError(); 5288 5289 // Recover by assuming we had the right type all along. 5290 DestructedType = ObjectType; 5291 } else 5292 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 5293 } else { 5294 // Resolve the template-id to a type. 5295 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 5296 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5297 TemplateId->NumArgs); 5298 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5299 TemplateId->TemplateKWLoc, 5300 TemplateId->Template, 5301 TemplateId->TemplateNameLoc, 5302 TemplateId->LAngleLoc, 5303 TemplateArgsPtr, 5304 TemplateId->RAngleLoc); 5305 if (T.isInvalid() || !T.get()) { 5306 // Recover by assuming we had the right type all along. 5307 DestructedType = ObjectType; 5308 } else 5309 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 5310 } 5311 5312 // If we've performed some kind of recovery, (re-)build the type source 5313 // information. 5314 if (!DestructedType.isNull()) { 5315 if (!DestructedTypeInfo) 5316 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 5317 SecondTypeName.StartLocation); 5318 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5319 } 5320 5321 // Convert the name of the scope type (the type prior to '::') into a type. 5322 TypeSourceInfo *ScopeTypeInfo = 0; 5323 QualType ScopeType; 5324 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5325 FirstTypeName.Identifier) { 5326 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5327 ParsedType T = getTypeName(*FirstTypeName.Identifier, 5328 FirstTypeName.StartLocation, 5329 S, &SS, true, false, ObjectTypePtrForLookup); 5330 if (!T) { 5331 Diag(FirstTypeName.StartLocation, 5332 diag::err_pseudo_dtor_destructor_non_type) 5333 << FirstTypeName.Identifier << ObjectType; 5334 5335 if (isSFINAEContext()) 5336 return ExprError(); 5337 5338 // Just drop this type. It's unnecessary anyway. 5339 ScopeType = QualType(); 5340 } else 5341 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 5342 } else { 5343 // Resolve the template-id to a type. 5344 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 5345 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5346 TemplateId->NumArgs); 5347 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5348 TemplateId->TemplateKWLoc, 5349 TemplateId->Template, 5350 TemplateId->TemplateNameLoc, 5351 TemplateId->LAngleLoc, 5352 TemplateArgsPtr, 5353 TemplateId->RAngleLoc); 5354 if (T.isInvalid() || !T.get()) { 5355 // Recover by dropping this type. 5356 ScopeType = QualType(); 5357 } else 5358 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 5359 } 5360 } 5361 5362 if (!ScopeType.isNull() && !ScopeTypeInfo) 5363 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 5364 FirstTypeName.StartLocation); 5365 5366 5367 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 5368 ScopeTypeInfo, CCLoc, TildeLoc, 5369 Destructed, HasTrailingLParen); 5370} 5371 5372ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5373 SourceLocation OpLoc, 5374 tok::TokenKind OpKind, 5375 SourceLocation TildeLoc, 5376 const DeclSpec& DS, 5377 bool HasTrailingLParen) { 5378 QualType ObjectType; 5379 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5380 return ExprError(); 5381 5382 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 5383 5384 TypeLocBuilder TLB; 5385 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 5386 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 5387 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 5388 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 5389 5390 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 5391 0, SourceLocation(), TildeLoc, 5392 Destructed, HasTrailingLParen); 5393} 5394 5395ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 5396 CXXConversionDecl *Method, 5397 bool HadMultipleCandidates) { 5398 if (Method->getParent()->isLambda() && 5399 Method->getConversionType()->isBlockPointerType()) { 5400 // This is a lambda coversion to block pointer; check if the argument 5401 // is a LambdaExpr. 5402 Expr *SubE = E; 5403 CastExpr *CE = dyn_cast<CastExpr>(SubE); 5404 if (CE && CE->getCastKind() == CK_NoOp) 5405 SubE = CE->getSubExpr(); 5406 SubE = SubE->IgnoreParens(); 5407 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE)) 5408 SubE = BE->getSubExpr(); 5409 if (isa<LambdaExpr>(SubE)) { 5410 // For the conversion to block pointer on a lambda expression, we 5411 // construct a special BlockLiteral instead; this doesn't really make 5412 // a difference in ARC, but outside of ARC the resulting block literal 5413 // follows the normal lifetime rules for block literals instead of being 5414 // autoreleased. 5415 DiagnosticErrorTrap Trap(Diags); 5416 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(), 5417 E->getExprLoc(), 5418 Method, E); 5419 if (Exp.isInvalid()) 5420 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv); 5421 return Exp; 5422 } 5423 } 5424 5425 5426 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 5427 FoundDecl, Method); 5428 if (Exp.isInvalid()) 5429 return true; 5430 5431 MemberExpr *ME = 5432 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 5433 SourceLocation(), Context.BoundMemberTy, 5434 VK_RValue, OK_Ordinary); 5435 if (HadMultipleCandidates) 5436 ME->setHadMultipleCandidates(true); 5437 MarkMemberReferenced(ME); 5438 5439 QualType ResultType = Method->getResultType(); 5440 ExprValueKind VK = Expr::getValueKindForType(ResultType); 5441 ResultType = ResultType.getNonLValueExprType(Context); 5442 5443 CXXMemberCallExpr *CE = 5444 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK, 5445 Exp.get()->getLocEnd()); 5446 return CE; 5447} 5448 5449ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 5450 SourceLocation RParen) { 5451 CanThrowResult CanThrow = canThrow(Operand); 5452 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 5453 CanThrow, KeyLoc, RParen)); 5454} 5455 5456ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 5457 Expr *Operand, SourceLocation RParen) { 5458 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 5459} 5460 5461static bool IsSpecialDiscardedValue(Expr *E) { 5462 // In C++11, discarded-value expressions of a certain form are special, 5463 // according to [expr]p10: 5464 // The lvalue-to-rvalue conversion (4.1) is applied only if the 5465 // expression is an lvalue of volatile-qualified type and it has 5466 // one of the following forms: 5467 E = E->IgnoreParens(); 5468 5469 // - id-expression (5.1.1), 5470 if (isa<DeclRefExpr>(E)) 5471 return true; 5472 5473 // - subscripting (5.2.1), 5474 if (isa<ArraySubscriptExpr>(E)) 5475 return true; 5476 5477 // - class member access (5.2.5), 5478 if (isa<MemberExpr>(E)) 5479 return true; 5480 5481 // - indirection (5.3.1), 5482 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) 5483 if (UO->getOpcode() == UO_Deref) 5484 return true; 5485 5486 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 5487 // - pointer-to-member operation (5.5), 5488 if (BO->isPtrMemOp()) 5489 return true; 5490 5491 // - comma expression (5.18) where the right operand is one of the above. 5492 if (BO->getOpcode() == BO_Comma) 5493 return IsSpecialDiscardedValue(BO->getRHS()); 5494 } 5495 5496 // - conditional expression (5.16) where both the second and the third 5497 // operands are one of the above, or 5498 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) 5499 return IsSpecialDiscardedValue(CO->getTrueExpr()) && 5500 IsSpecialDiscardedValue(CO->getFalseExpr()); 5501 // The related edge case of "*x ?: *x". 5502 if (BinaryConditionalOperator *BCO = 5503 dyn_cast<BinaryConditionalOperator>(E)) { 5504 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr())) 5505 return IsSpecialDiscardedValue(OVE->getSourceExpr()) && 5506 IsSpecialDiscardedValue(BCO->getFalseExpr()); 5507 } 5508 5509 // Objective-C++ extensions to the rule. 5510 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E)) 5511 return true; 5512 5513 return false; 5514} 5515 5516/// Perform the conversions required for an expression used in a 5517/// context that ignores the result. 5518ExprResult Sema::IgnoredValueConversions(Expr *E) { 5519 if (E->hasPlaceholderType()) { 5520 ExprResult result = CheckPlaceholderExpr(E); 5521 if (result.isInvalid()) return Owned(E); 5522 E = result.take(); 5523 } 5524 5525 // C99 6.3.2.1: 5526 // [Except in specific positions,] an lvalue that does not have 5527 // array type is converted to the value stored in the 5528 // designated object (and is no longer an lvalue). 5529 if (E->isRValue()) { 5530 // In C, function designators (i.e. expressions of function type) 5531 // are r-values, but we still want to do function-to-pointer decay 5532 // on them. This is both technically correct and convenient for 5533 // some clients. 5534 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType()) 5535 return DefaultFunctionArrayConversion(E); 5536 5537 return Owned(E); 5538 } 5539 5540 if (getLangOpts().CPlusPlus) { 5541 // The C++11 standard defines the notion of a discarded-value expression; 5542 // normally, we don't need to do anything to handle it, but if it is a 5543 // volatile lvalue with a special form, we perform an lvalue-to-rvalue 5544 // conversion. 5545 if (getLangOpts().CPlusPlus11 && E->isGLValue() && 5546 E->getType().isVolatileQualified() && 5547 IsSpecialDiscardedValue(E)) { 5548 ExprResult Res = DefaultLvalueConversion(E); 5549 if (Res.isInvalid()) 5550 return Owned(E); 5551 E = Res.take(); 5552 } 5553 return Owned(E); 5554 } 5555 5556 // GCC seems to also exclude expressions of incomplete enum type. 5557 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 5558 if (!T->getDecl()->isComplete()) { 5559 // FIXME: stupid workaround for a codegen bug! 5560 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 5561 return Owned(E); 5562 } 5563 } 5564 5565 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 5566 if (Res.isInvalid()) 5567 return Owned(E); 5568 E = Res.take(); 5569 5570 if (!E->getType()->isVoidType()) 5571 RequireCompleteType(E->getExprLoc(), E->getType(), 5572 diag::err_incomplete_type); 5573 return Owned(E); 5574} 5575 5576ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC, 5577 bool DiscardedValue, 5578 bool IsConstexpr) { 5579 ExprResult FullExpr = Owned(FE); 5580 5581 if (!FullExpr.get()) 5582 return ExprError(); 5583 5584 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 5585 return ExprError(); 5586 5587 // Top-level expressions default to 'id' when we're in a debugger. 5588 if (DiscardedValue && getLangOpts().DebuggerCastResultToId && 5589 FullExpr.get()->getType() == Context.UnknownAnyTy) { 5590 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 5591 if (FullExpr.isInvalid()) 5592 return ExprError(); 5593 } 5594 5595 if (DiscardedValue) { 5596 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 5597 if (FullExpr.isInvalid()) 5598 return ExprError(); 5599 5600 FullExpr = IgnoredValueConversions(FullExpr.take()); 5601 if (FullExpr.isInvalid()) 5602 return ExprError(); 5603 } 5604 5605 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr); 5606 return MaybeCreateExprWithCleanups(FullExpr); 5607} 5608 5609StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 5610 if (!FullStmt) return StmtError(); 5611 5612 return MaybeCreateStmtWithCleanups(FullStmt); 5613} 5614 5615Sema::IfExistsResult 5616Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 5617 CXXScopeSpec &SS, 5618 const DeclarationNameInfo &TargetNameInfo) { 5619 DeclarationName TargetName = TargetNameInfo.getName(); 5620 if (!TargetName) 5621 return IER_DoesNotExist; 5622 5623 // If the name itself is dependent, then the result is dependent. 5624 if (TargetName.isDependentName()) 5625 return IER_Dependent; 5626 5627 // Do the redeclaration lookup in the current scope. 5628 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 5629 Sema::NotForRedeclaration); 5630 LookupParsedName(R, S, &SS); 5631 R.suppressDiagnostics(); 5632 5633 switch (R.getResultKind()) { 5634 case LookupResult::Found: 5635 case LookupResult::FoundOverloaded: 5636 case LookupResult::FoundUnresolvedValue: 5637 case LookupResult::Ambiguous: 5638 return IER_Exists; 5639 5640 case LookupResult::NotFound: 5641 return IER_DoesNotExist; 5642 5643 case LookupResult::NotFoundInCurrentInstantiation: 5644 return IER_Dependent; 5645 } 5646 5647 llvm_unreachable("Invalid LookupResult Kind!"); 5648} 5649 5650Sema::IfExistsResult 5651Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 5652 bool IsIfExists, CXXScopeSpec &SS, 5653 UnqualifiedId &Name) { 5654 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 5655 5656 // Check for unexpanded parameter packs. 5657 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 5658 collectUnexpandedParameterPacks(SS, Unexpanded); 5659 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 5660 if (!Unexpanded.empty()) { 5661 DiagnoseUnexpandedParameterPacks(KeywordLoc, 5662 IsIfExists? UPPC_IfExists 5663 : UPPC_IfNotExists, 5664 Unexpanded); 5665 return IER_Error; 5666 } 5667 5668 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 5669} 5670