SemaExprCXX.cpp revision bd45d257a404ed1f87090c8a32b5dd75576b7d11
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// This file implements semantic analysis for C++ expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/DeclSpec.h" 16#include "clang/Sema/Initialization.h" 17#include "clang/Sema/Lookup.h" 18#include "clang/Sema/ParsedTemplate.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "clang/Sema/Scope.h" 21#include "clang/Sema/TemplateDeduction.h" 22#include "clang/AST/ASTContext.h" 23#include "clang/AST/CharUnits.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/ExprCXX.h" 27#include "clang/AST/ExprObjC.h" 28#include "clang/AST/TypeLoc.h" 29#include "clang/Basic/PartialDiagnostic.h" 30#include "clang/Basic/TargetInfo.h" 31#include "clang/Lex/Preprocessor.h" 32#include "TypeLocBuilder.h" 33#include "llvm/ADT/APInt.h" 34#include "llvm/ADT/STLExtras.h" 35#include "llvm/Support/ErrorHandling.h" 36using namespace clang; 37using namespace sema; 38 39ParsedType Sema::getDestructorName(SourceLocation TildeLoc, 40 IdentifierInfo &II, 41 SourceLocation NameLoc, 42 Scope *S, CXXScopeSpec &SS, 43 ParsedType ObjectTypePtr, 44 bool EnteringContext) { 45 // Determine where to perform name lookup. 46 47 // FIXME: This area of the standard is very messy, and the current 48 // wording is rather unclear about which scopes we search for the 49 // destructor name; see core issues 399 and 555. Issue 399 in 50 // particular shows where the current description of destructor name 51 // lookup is completely out of line with existing practice, e.g., 52 // this appears to be ill-formed: 53 // 54 // namespace N { 55 // template <typename T> struct S { 56 // ~S(); 57 // }; 58 // } 59 // 60 // void f(N::S<int>* s) { 61 // s->N::S<int>::~S(); 62 // } 63 // 64 // See also PR6358 and PR6359. 65 // For this reason, we're currently only doing the C++03 version of this 66 // code; the C++0x version has to wait until we get a proper spec. 67 QualType SearchType; 68 DeclContext *LookupCtx = 0; 69 bool isDependent = false; 70 bool LookInScope = false; 71 72 // If we have an object type, it's because we are in a 73 // pseudo-destructor-expression or a member access expression, and 74 // we know what type we're looking for. 75 if (ObjectTypePtr) 76 SearchType = GetTypeFromParser(ObjectTypePtr); 77 78 if (SS.isSet()) { 79 NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 80 81 bool AlreadySearched = false; 82 bool LookAtPrefix = true; 83 // C++ [basic.lookup.qual]p6: 84 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier, 85 // the type-names are looked up as types in the scope designated by the 86 // nested-name-specifier. In a qualified-id of the form: 87 // 88 // ::[opt] nested-name-specifier ~ class-name 89 // 90 // where the nested-name-specifier designates a namespace scope, and in 91 // a qualified-id of the form: 92 // 93 // ::opt nested-name-specifier class-name :: ~ class-name 94 // 95 // the class-names are looked up as types in the scope designated by 96 // the nested-name-specifier. 97 // 98 // Here, we check the first case (completely) and determine whether the 99 // code below is permitted to look at the prefix of the 100 // nested-name-specifier. 101 DeclContext *DC = computeDeclContext(SS, EnteringContext); 102 if (DC && DC->isFileContext()) { 103 AlreadySearched = true; 104 LookupCtx = DC; 105 isDependent = false; 106 } else if (DC && isa<CXXRecordDecl>(DC)) 107 LookAtPrefix = false; 108 109 // The second case from the C++03 rules quoted further above. 110 NestedNameSpecifier *Prefix = 0; 111 if (AlreadySearched) { 112 // Nothing left to do. 113 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) { 114 CXXScopeSpec PrefixSS; 115 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data())); 116 LookupCtx = computeDeclContext(PrefixSS, EnteringContext); 117 isDependent = isDependentScopeSpecifier(PrefixSS); 118 } else if (ObjectTypePtr) { 119 LookupCtx = computeDeclContext(SearchType); 120 isDependent = SearchType->isDependentType(); 121 } else { 122 LookupCtx = computeDeclContext(SS, EnteringContext); 123 isDependent = LookupCtx && LookupCtx->isDependentContext(); 124 } 125 126 LookInScope = false; 127 } else if (ObjectTypePtr) { 128 // C++ [basic.lookup.classref]p3: 129 // If the unqualified-id is ~type-name, the type-name is looked up 130 // in the context of the entire postfix-expression. If the type T 131 // of the object expression is of a class type C, the type-name is 132 // also looked up in the scope of class C. At least one of the 133 // lookups shall find a name that refers to (possibly 134 // cv-qualified) T. 135 LookupCtx = computeDeclContext(SearchType); 136 isDependent = SearchType->isDependentType(); 137 assert((isDependent || !SearchType->isIncompleteType()) && 138 "Caller should have completed object type"); 139 140 LookInScope = true; 141 } else { 142 // Perform lookup into the current scope (only). 143 LookInScope = true; 144 } 145 146 TypeDecl *NonMatchingTypeDecl = 0; 147 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName); 148 for (unsigned Step = 0; Step != 2; ++Step) { 149 // Look for the name first in the computed lookup context (if we 150 // have one) and, if that fails to find a match, in the scope (if 151 // we're allowed to look there). 152 Found.clear(); 153 if (Step == 0 && LookupCtx) 154 LookupQualifiedName(Found, LookupCtx); 155 else if (Step == 1 && LookInScope && S) 156 LookupName(Found, S); 157 else 158 continue; 159 160 // FIXME: Should we be suppressing ambiguities here? 161 if (Found.isAmbiguous()) 162 return ParsedType(); 163 164 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) { 165 QualType T = Context.getTypeDeclType(Type); 166 167 if (SearchType.isNull() || SearchType->isDependentType() || 168 Context.hasSameUnqualifiedType(T, SearchType)) { 169 // We found our type! 170 171 return ParsedType::make(T); 172 } 173 174 if (!SearchType.isNull()) 175 NonMatchingTypeDecl = Type; 176 } 177 178 // If the name that we found is a class template name, and it is 179 // the same name as the template name in the last part of the 180 // nested-name-specifier (if present) or the object type, then 181 // this is the destructor for that class. 182 // FIXME: This is a workaround until we get real drafting for core 183 // issue 399, for which there isn't even an obvious direction. 184 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) { 185 QualType MemberOfType; 186 if (SS.isSet()) { 187 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) { 188 // Figure out the type of the context, if it has one. 189 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) 190 MemberOfType = Context.getTypeDeclType(Record); 191 } 192 } 193 if (MemberOfType.isNull()) 194 MemberOfType = SearchType; 195 196 if (MemberOfType.isNull()) 197 continue; 198 199 // We're referring into a class template specialization. If the 200 // class template we found is the same as the template being 201 // specialized, we found what we are looking for. 202 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) { 203 if (ClassTemplateSpecializationDecl *Spec 204 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) { 205 if (Spec->getSpecializedTemplate()->getCanonicalDecl() == 206 Template->getCanonicalDecl()) 207 return ParsedType::make(MemberOfType); 208 } 209 210 continue; 211 } 212 213 // We're referring to an unresolved class template 214 // specialization. Determine whether we class template we found 215 // is the same as the template being specialized or, if we don't 216 // know which template is being specialized, that it at least 217 // has the same name. 218 if (const TemplateSpecializationType *SpecType 219 = MemberOfType->getAs<TemplateSpecializationType>()) { 220 TemplateName SpecName = SpecType->getTemplateName(); 221 222 // The class template we found is the same template being 223 // specialized. 224 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) { 225 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl()) 226 return ParsedType::make(MemberOfType); 227 228 continue; 229 } 230 231 // The class template we found has the same name as the 232 // (dependent) template name being specialized. 233 if (DependentTemplateName *DepTemplate 234 = SpecName.getAsDependentTemplateName()) { 235 if (DepTemplate->isIdentifier() && 236 DepTemplate->getIdentifier() == Template->getIdentifier()) 237 return ParsedType::make(MemberOfType); 238 239 continue; 240 } 241 } 242 } 243 } 244 245 if (isDependent) { 246 // We didn't find our type, but that's okay: it's dependent 247 // anyway. 248 249 // FIXME: What if we have no nested-name-specifier? 250 QualType T = CheckTypenameType(ETK_None, SourceLocation(), 251 SS.getWithLocInContext(Context), 252 II, NameLoc); 253 return ParsedType::make(T); 254 } 255 256 if (NonMatchingTypeDecl) { 257 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl); 258 Diag(NameLoc, diag::err_destructor_expr_type_mismatch) 259 << T << SearchType; 260 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here) 261 << T; 262 } else if (ObjectTypePtr) 263 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type) 264 << &II; 265 else 266 Diag(NameLoc, diag::err_destructor_class_name); 267 268 return ParsedType(); 269} 270 271ParsedType Sema::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) { 272 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType) 273 return ParsedType(); 274 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype 275 && "only get destructor types from declspecs"); 276 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 277 QualType SearchType = GetTypeFromParser(ObjectType); 278 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) { 279 return ParsedType::make(T); 280 } 281 282 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch) 283 << T << SearchType; 284 return ParsedType(); 285} 286 287/// \brief Build a C++ typeid expression with a type operand. 288ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 289 SourceLocation TypeidLoc, 290 TypeSourceInfo *Operand, 291 SourceLocation RParenLoc) { 292 // C++ [expr.typeid]p4: 293 // The top-level cv-qualifiers of the lvalue expression or the type-id 294 // that is the operand of typeid are always ignored. 295 // If the type of the type-id is a class type or a reference to a class 296 // type, the class shall be completely-defined. 297 Qualifiers Quals; 298 QualType T 299 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(), 300 Quals); 301 if (T->getAs<RecordType>() && 302 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 303 return ExprError(); 304 305 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 306 Operand, 307 SourceRange(TypeidLoc, RParenLoc))); 308} 309 310/// \brief Build a C++ typeid expression with an expression operand. 311ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 312 SourceLocation TypeidLoc, 313 Expr *E, 314 SourceLocation RParenLoc) { 315 if (E && !E->isTypeDependent()) { 316 if (E->getType()->isPlaceholderType()) { 317 ExprResult result = CheckPlaceholderExpr(E); 318 if (result.isInvalid()) return ExprError(); 319 E = result.take(); 320 } 321 322 QualType T = E->getType(); 323 if (const RecordType *RecordT = T->getAs<RecordType>()) { 324 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl()); 325 // C++ [expr.typeid]p3: 326 // [...] If the type of the expression is a class type, the class 327 // shall be completely-defined. 328 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 329 return ExprError(); 330 331 // C++ [expr.typeid]p3: 332 // When typeid is applied to an expression other than an glvalue of a 333 // polymorphic class type [...] [the] expression is an unevaluated 334 // operand. [...] 335 if (RecordD->isPolymorphic() && E->Classify(Context).isGLValue()) { 336 // The subexpression is potentially evaluated; switch the context 337 // and recheck the subexpression. 338 ExprResult Result = TranformToPotentiallyEvaluated(E); 339 if (Result.isInvalid()) return ExprError(); 340 E = Result.take(); 341 342 // We require a vtable to query the type at run time. 343 MarkVTableUsed(TypeidLoc, RecordD); 344 } 345 } 346 347 // C++ [expr.typeid]p4: 348 // [...] If the type of the type-id is a reference to a possibly 349 // cv-qualified type, the result of the typeid expression refers to a 350 // std::type_info object representing the cv-unqualified referenced 351 // type. 352 Qualifiers Quals; 353 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals); 354 if (!Context.hasSameType(T, UnqualT)) { 355 T = UnqualT; 356 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).take(); 357 } 358 } 359 360 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 361 E, 362 SourceRange(TypeidLoc, RParenLoc))); 363} 364 365/// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression); 366ExprResult 367Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc, 368 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 369 // Find the std::type_info type. 370 if (!getStdNamespace()) 371 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 372 373 if (!CXXTypeInfoDecl) { 374 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info"); 375 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName); 376 LookupQualifiedName(R, getStdNamespace()); 377 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 378 if (!CXXTypeInfoDecl) 379 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 380 } 381 382 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl); 383 384 if (isType) { 385 // The operand is a type; handle it as such. 386 TypeSourceInfo *TInfo = 0; 387 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 388 &TInfo); 389 if (T.isNull()) 390 return ExprError(); 391 392 if (!TInfo) 393 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 394 395 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc); 396 } 397 398 // The operand is an expression. 399 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 400} 401 402/// Retrieve the UuidAttr associated with QT. 403static UuidAttr *GetUuidAttrOfType(QualType QT) { 404 // Optionally remove one level of pointer, reference or array indirection. 405 const Type *Ty = QT.getTypePtr();; 406 if (QT->isPointerType() || QT->isReferenceType()) 407 Ty = QT->getPointeeType().getTypePtr(); 408 else if (QT->isArrayType()) 409 Ty = cast<ArrayType>(QT)->getElementType().getTypePtr(); 410 411 // Loop all record redeclaration looking for an uuid attribute. 412 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl(); 413 for (CXXRecordDecl::redecl_iterator I = RD->redecls_begin(), 414 E = RD->redecls_end(); I != E; ++I) { 415 if (UuidAttr *Uuid = I->getAttr<UuidAttr>()) 416 return Uuid; 417 } 418 419 return 0; 420} 421 422/// \brief Build a Microsoft __uuidof expression with a type operand. 423ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 424 SourceLocation TypeidLoc, 425 TypeSourceInfo *Operand, 426 SourceLocation RParenLoc) { 427 if (!Operand->getType()->isDependentType()) { 428 if (!GetUuidAttrOfType(Operand->getType())) 429 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 430 } 431 432 // FIXME: add __uuidof semantic analysis for type operand. 433 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 434 Operand, 435 SourceRange(TypeidLoc, RParenLoc))); 436} 437 438/// \brief Build a Microsoft __uuidof expression with an expression operand. 439ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 440 SourceLocation TypeidLoc, 441 Expr *E, 442 SourceLocation RParenLoc) { 443 if (!E->getType()->isDependentType()) { 444 if (!GetUuidAttrOfType(E->getType()) && 445 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 446 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 447 } 448 // FIXME: add __uuidof semantic analysis for type operand. 449 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 450 E, 451 SourceRange(TypeidLoc, RParenLoc))); 452} 453 454/// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression); 455ExprResult 456Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc, 457 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 458 // If MSVCGuidDecl has not been cached, do the lookup. 459 if (!MSVCGuidDecl) { 460 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID"); 461 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName); 462 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 463 MSVCGuidDecl = R.getAsSingle<RecordDecl>(); 464 if (!MSVCGuidDecl) 465 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof)); 466 } 467 468 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl); 469 470 if (isType) { 471 // The operand is a type; handle it as such. 472 TypeSourceInfo *TInfo = 0; 473 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 474 &TInfo); 475 if (T.isNull()) 476 return ExprError(); 477 478 if (!TInfo) 479 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 480 481 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc); 482 } 483 484 // The operand is an expression. 485 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 486} 487 488/// ActOnCXXBoolLiteral - Parse {true,false} literals. 489ExprResult 490Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 491 assert((Kind == tok::kw_true || Kind == tok::kw_false) && 492 "Unknown C++ Boolean value!"); 493 return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true, 494 Context.BoolTy, OpLoc)); 495} 496 497/// ActOnCXXNullPtrLiteral - Parse 'nullptr'. 498ExprResult 499Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) { 500 return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc)); 501} 502 503/// ActOnCXXThrow - Parse throw expressions. 504ExprResult 505Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) { 506 bool IsThrownVarInScope = false; 507 if (Ex) { 508 // C++0x [class.copymove]p31: 509 // When certain criteria are met, an implementation is allowed to omit the 510 // copy/move construction of a class object [...] 511 // 512 // - in a throw-expression, when the operand is the name of a 513 // non-volatile automatic object (other than a function or catch- 514 // clause parameter) whose scope does not extend beyond the end of the 515 // innermost enclosing try-block (if there is one), the copy/move 516 // operation from the operand to the exception object (15.1) can be 517 // omitted by constructing the automatic object directly into the 518 // exception object 519 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens())) 520 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 521 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) { 522 for( ; S; S = S->getParent()) { 523 if (S->isDeclScope(Var)) { 524 IsThrownVarInScope = true; 525 break; 526 } 527 528 if (S->getFlags() & 529 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope | 530 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope | 531 Scope::TryScope)) 532 break; 533 } 534 } 535 } 536 } 537 538 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope); 539} 540 541ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex, 542 bool IsThrownVarInScope) { 543 // Don't report an error if 'throw' is used in system headers. 544 if (!getLangOptions().CXXExceptions && 545 !getSourceManager().isInSystemHeader(OpLoc)) 546 Diag(OpLoc, diag::err_exceptions_disabled) << "throw"; 547 548 if (Ex && !Ex->isTypeDependent()) { 549 ExprResult ExRes = CheckCXXThrowOperand(OpLoc, Ex, IsThrownVarInScope); 550 if (ExRes.isInvalid()) 551 return ExprError(); 552 Ex = ExRes.take(); 553 } 554 555 return Owned(new (Context) CXXThrowExpr(Ex, Context.VoidTy, OpLoc, 556 IsThrownVarInScope)); 557} 558 559/// CheckCXXThrowOperand - Validate the operand of a throw. 560ExprResult Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *E, 561 bool IsThrownVarInScope) { 562 // C++ [except.throw]p3: 563 // A throw-expression initializes a temporary object, called the exception 564 // object, the type of which is determined by removing any top-level 565 // cv-qualifiers from the static type of the operand of throw and adjusting 566 // the type from "array of T" or "function returning T" to "pointer to T" 567 // or "pointer to function returning T", [...] 568 if (E->getType().hasQualifiers()) 569 E = ImpCastExprToType(E, E->getType().getUnqualifiedType(), CK_NoOp, 570 E->getValueKind()).take(); 571 572 ExprResult Res = DefaultFunctionArrayConversion(E); 573 if (Res.isInvalid()) 574 return ExprError(); 575 E = Res.take(); 576 577 // If the type of the exception would be an incomplete type or a pointer 578 // to an incomplete type other than (cv) void the program is ill-formed. 579 QualType Ty = E->getType(); 580 bool isPointer = false; 581 if (const PointerType* Ptr = Ty->getAs<PointerType>()) { 582 Ty = Ptr->getPointeeType(); 583 isPointer = true; 584 } 585 if (!isPointer || !Ty->isVoidType()) { 586 if (RequireCompleteType(ThrowLoc, Ty, 587 PDiag(isPointer ? diag::err_throw_incomplete_ptr 588 : diag::err_throw_incomplete) 589 << E->getSourceRange())) 590 return ExprError(); 591 592 if (RequireNonAbstractType(ThrowLoc, E->getType(), 593 PDiag(diag::err_throw_abstract_type) 594 << E->getSourceRange())) 595 return ExprError(); 596 } 597 598 // Initialize the exception result. This implicitly weeds out 599 // abstract types or types with inaccessible copy constructors. 600 601 // C++0x [class.copymove]p31: 602 // When certain criteria are met, an implementation is allowed to omit the 603 // copy/move construction of a class object [...] 604 // 605 // - in a throw-expression, when the operand is the name of a 606 // non-volatile automatic object (other than a function or catch-clause 607 // parameter) whose scope does not extend beyond the end of the 608 // innermost enclosing try-block (if there is one), the copy/move 609 // operation from the operand to the exception object (15.1) can be 610 // omitted by constructing the automatic object directly into the 611 // exception object 612 const VarDecl *NRVOVariable = 0; 613 if (IsThrownVarInScope) 614 NRVOVariable = getCopyElisionCandidate(QualType(), E, false); 615 616 InitializedEntity Entity = 617 InitializedEntity::InitializeException(ThrowLoc, E->getType(), 618 /*NRVO=*/NRVOVariable != 0); 619 Res = PerformMoveOrCopyInitialization(Entity, NRVOVariable, 620 QualType(), E, 621 IsThrownVarInScope); 622 if (Res.isInvalid()) 623 return ExprError(); 624 E = Res.take(); 625 626 // If the exception has class type, we need additional handling. 627 const RecordType *RecordTy = Ty->getAs<RecordType>(); 628 if (!RecordTy) 629 return Owned(E); 630 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl()); 631 632 // If we are throwing a polymorphic class type or pointer thereof, 633 // exception handling will make use of the vtable. 634 MarkVTableUsed(ThrowLoc, RD); 635 636 // If a pointer is thrown, the referenced object will not be destroyed. 637 if (isPointer) 638 return Owned(E); 639 640 // If the class has a non-trivial destructor, we must be able to call it. 641 if (RD->hasTrivialDestructor()) 642 return Owned(E); 643 644 CXXDestructorDecl *Destructor 645 = const_cast<CXXDestructorDecl*>(LookupDestructor(RD)); 646 if (!Destructor) 647 return Owned(E); 648 649 MarkFunctionReferenced(E->getExprLoc(), Destructor); 650 CheckDestructorAccess(E->getExprLoc(), Destructor, 651 PDiag(diag::err_access_dtor_exception) << Ty); 652 return Owned(E); 653} 654 655QualType Sema::getCurrentThisType() { 656 DeclContext *DC = getFunctionLevelDeclContext(); 657 QualType ThisTy; 658 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) { 659 if (method && method->isInstance()) 660 ThisTy = method->getThisType(Context); 661 } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 662 // C++0x [expr.prim]p4: 663 // Otherwise, if a member-declarator declares a non-static data member 664 // of a class X, the expression this is a prvalue of type "pointer to X" 665 // within the optional brace-or-equal-initializer. 666 Scope *S = getScopeForContext(DC); 667 if (!S || S->getFlags() & Scope::ThisScope) 668 ThisTy = Context.getPointerType(Context.getRecordType(RD)); 669 } 670 671 return ThisTy; 672} 673 674void Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit) { 675 // We don't need to capture this in an unevaluated context. 676 if (ExprEvalContexts.back().Context == Unevaluated && !Explicit) 677 return; 678 679 // Otherwise, check that we can capture 'this'. 680 unsigned NumClosures = 0; 681 for (unsigned idx = FunctionScopes.size() - 1; idx != 0; idx--) { 682 if (CapturingScopeInfo *CSI = 683 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) { 684 if (CSI->CXXThisCaptureIndex != 0) { 685 // 'this' is already being captured; there isn't anything more to do. 686 break; 687 } 688 689 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref || 690 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval || 691 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block || 692 Explicit) { 693 // This closure can capture 'this'; continue looking upwards. 694 NumClosures++; 695 Explicit = false; 696 continue; 697 } 698 // This context can't implicitly capture 'this'; fail out. 699 Diag(Loc, diag::err_this_capture) << Explicit; 700 return; 701 } 702 break; 703 } 704 705 // Mark that we're implicitly capturing 'this' in all the scopes we skipped. 706 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated 707 // contexts. 708 for (unsigned idx = FunctionScopes.size() - 1; 709 NumClosures; --idx, --NumClosures) { 710 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]); 711 Expr *ThisExpr = 0; 712 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) { 713 // For lambda expressions, build a field and an initializing expression. 714 QualType ThisTy = getCurrentThisType(); 715 CXXRecordDecl *Lambda = LSI->Lambda; 716 FieldDecl *Field 717 = FieldDecl::Create(Context, Lambda, Loc, Loc, 0, ThisTy, 718 Context.getTrivialTypeSourceInfo(ThisTy, Loc), 719 0, false, false); 720 Field->setImplicit(true); 721 Field->setAccess(AS_private); 722 Lambda->addDecl(Field); 723 ThisExpr = new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/true); 724 } 725 bool isNested = NumClosures > 1; 726 CSI->AddThisCapture(isNested, Loc, ThisExpr); 727 } 728} 729 730ExprResult Sema::ActOnCXXThis(SourceLocation Loc) { 731 /// C++ 9.3.2: In the body of a non-static member function, the keyword this 732 /// is a non-lvalue expression whose value is the address of the object for 733 /// which the function is called. 734 735 QualType ThisTy = getCurrentThisType(); 736 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use); 737 738 CheckCXXThisCapture(Loc); 739 return Owned(new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false)); 740} 741 742ExprResult 743Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep, 744 SourceLocation LParenLoc, 745 MultiExprArg exprs, 746 SourceLocation RParenLoc) { 747 if (!TypeRep) 748 return ExprError(); 749 750 TypeSourceInfo *TInfo; 751 QualType Ty = GetTypeFromParser(TypeRep, &TInfo); 752 if (!TInfo) 753 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation()); 754 755 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc); 756} 757 758/// ActOnCXXTypeConstructExpr - Parse construction of a specified type. 759/// Can be interpreted either as function-style casting ("int(x)") 760/// or class type construction ("ClassType(x,y,z)") 761/// or creation of a value-initialized type ("int()"). 762ExprResult 763Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, 764 SourceLocation LParenLoc, 765 MultiExprArg exprs, 766 SourceLocation RParenLoc) { 767 QualType Ty = TInfo->getType(); 768 unsigned NumExprs = exprs.size(); 769 Expr **Exprs = (Expr**)exprs.get(); 770 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); 771 772 if (Ty->isDependentType() || 773 CallExpr::hasAnyTypeDependentArguments(Exprs, NumExprs)) { 774 exprs.release(); 775 776 return Owned(CXXUnresolvedConstructExpr::Create(Context, TInfo, 777 LParenLoc, 778 Exprs, NumExprs, 779 RParenLoc)); 780 } 781 782 bool ListInitialization = LParenLoc.isInvalid(); 783 assert((!ListInitialization || (NumExprs == 1 && isa<InitListExpr>(Exprs[0]))) 784 && "List initialization must have initializer list as expression."); 785 SourceRange FullRange = SourceRange(TyBeginLoc, 786 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc); 787 788 if (Ty->isArrayType()) 789 return ExprError(Diag(TyBeginLoc, 790 diag::err_value_init_for_array_type) << FullRange); 791 if (!Ty->isVoidType() && 792 RequireCompleteType(TyBeginLoc, Ty, 793 PDiag(diag::err_invalid_incomplete_type_use) 794 << FullRange)) 795 return ExprError(); 796 797 if (RequireNonAbstractType(TyBeginLoc, Ty, 798 diag::err_allocation_of_abstract_type)) 799 return ExprError(); 800 801 802 // C++ [expr.type.conv]p1: 803 // If the expression list is a single expression, the type conversion 804 // expression is equivalent (in definedness, and if defined in meaning) to the 805 // corresponding cast expression. 806 if (NumExprs == 1 && !ListInitialization) { 807 Expr *Arg = Exprs[0]; 808 exprs.release(); 809 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc); 810 } 811 812 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo); 813 InitializationKind Kind 814 = NumExprs ? ListInitialization 815 ? InitializationKind::CreateDirectList(TyBeginLoc) 816 : InitializationKind::CreateDirect(TyBeginLoc, 817 LParenLoc, RParenLoc) 818 : InitializationKind::CreateValue(TyBeginLoc, 819 LParenLoc, RParenLoc); 820 InitializationSequence InitSeq(*this, Entity, Kind, Exprs, NumExprs); 821 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, move(exprs)); 822 823 if (!Result.isInvalid() && ListInitialization && 824 isa<InitListExpr>(Result.get())) { 825 // If the list-initialization doesn't involve a constructor call, we'll get 826 // the initializer-list (with corrected type) back, but that's not what we 827 // want, since it will be treated as an initializer list in further 828 // processing. Explicitly insert a cast here. 829 InitListExpr *List = cast<InitListExpr>(Result.take()); 830 Result = Owned(CXXFunctionalCastExpr::Create(Context, List->getType(), 831 Expr::getValueKindForType(TInfo->getType()), 832 TInfo, TyBeginLoc, CK_NoOp, 833 List, /*Path=*/0, RParenLoc)); 834 } 835 836 // FIXME: Improve AST representation? 837 return move(Result); 838} 839 840/// doesUsualArrayDeleteWantSize - Answers whether the usual 841/// operator delete[] for the given type has a size_t parameter. 842static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc, 843 QualType allocType) { 844 const RecordType *record = 845 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>(); 846 if (!record) return false; 847 848 // Try to find an operator delete[] in class scope. 849 850 DeclarationName deleteName = 851 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete); 852 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName); 853 S.LookupQualifiedName(ops, record->getDecl()); 854 855 // We're just doing this for information. 856 ops.suppressDiagnostics(); 857 858 // Very likely: there's no operator delete[]. 859 if (ops.empty()) return false; 860 861 // If it's ambiguous, it should be illegal to call operator delete[] 862 // on this thing, so it doesn't matter if we allocate extra space or not. 863 if (ops.isAmbiguous()) return false; 864 865 LookupResult::Filter filter = ops.makeFilter(); 866 while (filter.hasNext()) { 867 NamedDecl *del = filter.next()->getUnderlyingDecl(); 868 869 // C++0x [basic.stc.dynamic.deallocation]p2: 870 // A template instance is never a usual deallocation function, 871 // regardless of its signature. 872 if (isa<FunctionTemplateDecl>(del)) { 873 filter.erase(); 874 continue; 875 } 876 877 // C++0x [basic.stc.dynamic.deallocation]p2: 878 // If class T does not declare [an operator delete[] with one 879 // parameter] but does declare a member deallocation function 880 // named operator delete[] with exactly two parameters, the 881 // second of which has type std::size_t, then this function 882 // is a usual deallocation function. 883 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) { 884 filter.erase(); 885 continue; 886 } 887 } 888 filter.done(); 889 890 if (!ops.isSingleResult()) return false; 891 892 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl()); 893 return (del->getNumParams() == 2); 894} 895 896/// \brief Parsed a C++ 'new' expression (C++ 5.3.4). 897 898/// E.g.: 899/// @code new (memory) int[size][4] @endcode 900/// or 901/// @code ::new Foo(23, "hello") @endcode 902/// 903/// \param StartLoc The first location of the expression. 904/// \param UseGlobal True if 'new' was prefixed with '::'. 905/// \param PlacementLParen Opening paren of the placement arguments. 906/// \param PlacementArgs Placement new arguments. 907/// \param PlacementRParen Closing paren of the placement arguments. 908/// \param TypeIdParens If the type is in parens, the source range. 909/// \param D The type to be allocated, as well as array dimensions. 910/// \param ConstructorLParen Opening paren of the constructor args, empty if 911/// initializer-list syntax is used. 912/// \param ConstructorArgs Constructor/initialization arguments. 913/// \param ConstructorRParen Closing paren of the constructor args. 914ExprResult 915Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal, 916 SourceLocation PlacementLParen, MultiExprArg PlacementArgs, 917 SourceLocation PlacementRParen, SourceRange TypeIdParens, 918 Declarator &D, Expr *Initializer) { 919 bool TypeContainsAuto = D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto; 920 921 Expr *ArraySize = 0; 922 // If the specified type is an array, unwrap it and save the expression. 923 if (D.getNumTypeObjects() > 0 && 924 D.getTypeObject(0).Kind == DeclaratorChunk::Array) { 925 DeclaratorChunk &Chunk = D.getTypeObject(0); 926 if (TypeContainsAuto) 927 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto) 928 << D.getSourceRange()); 929 if (Chunk.Arr.hasStatic) 930 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new) 931 << D.getSourceRange()); 932 if (!Chunk.Arr.NumElts) 933 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size) 934 << D.getSourceRange()); 935 936 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts); 937 D.DropFirstTypeObject(); 938 } 939 940 // Every dimension shall be of constant size. 941 if (ArraySize) { 942 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) { 943 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array) 944 break; 945 946 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr; 947 if (Expr *NumElts = (Expr *)Array.NumElts) { 948 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) { 949 Array.NumElts = VerifyIntegerConstantExpression(NumElts, 0, 950 PDiag(diag::err_new_array_nonconst)).take(); 951 if (!Array.NumElts) 952 return ExprError(); 953 } 954 } 955 } 956 } 957 958 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/0); 959 QualType AllocType = TInfo->getType(); 960 if (D.isInvalidType()) 961 return ExprError(); 962 963 SourceRange DirectInitRange; 964 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) 965 DirectInitRange = List->getSourceRange(); 966 967 return BuildCXXNew(StartLoc, UseGlobal, 968 PlacementLParen, 969 move(PlacementArgs), 970 PlacementRParen, 971 TypeIdParens, 972 AllocType, 973 TInfo, 974 ArraySize, 975 DirectInitRange, 976 Initializer, 977 TypeContainsAuto); 978} 979 980static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style, 981 Expr *Init) { 982 if (!Init) 983 return true; 984 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init)) { 985 if (PLE->getNumExprs() != 1) 986 return PLE->getNumExprs() == 0; 987 Init = PLE->getExpr(0); 988 } 989 if (isa<ImplicitValueInitExpr>(Init)) 990 return true; 991 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) 992 return !CCE->isListInitialization() && 993 CCE->getConstructor()->isDefaultConstructor(); 994 else if (Style == CXXNewExpr::ListInit) { 995 assert(isa<InitListExpr>(Init) && 996 "Shouldn't create list CXXConstructExprs for arrays."); 997 return true; 998 } 999 return false; 1000} 1001 1002ExprResult 1003Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal, 1004 SourceLocation PlacementLParen, 1005 MultiExprArg PlacementArgs, 1006 SourceLocation PlacementRParen, 1007 SourceRange TypeIdParens, 1008 QualType AllocType, 1009 TypeSourceInfo *AllocTypeInfo, 1010 Expr *ArraySize, 1011 SourceRange DirectInitRange, 1012 Expr *Initializer, 1013 bool TypeMayContainAuto) { 1014 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange(); 1015 1016 CXXNewExpr::InitializationStyle initStyle; 1017 if (DirectInitRange.isValid()) { 1018 assert(Initializer && "Have parens but no initializer."); 1019 initStyle = CXXNewExpr::CallInit; 1020 } else if (Initializer && isa<InitListExpr>(Initializer)) 1021 initStyle = CXXNewExpr::ListInit; 1022 else { 1023 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) || 1024 isa<CXXConstructExpr>(Initializer)) && 1025 "Initializer expression that cannot have been implicitly created."); 1026 initStyle = CXXNewExpr::NoInit; 1027 } 1028 1029 Expr **Inits = &Initializer; 1030 unsigned NumInits = Initializer ? 1 : 0; 1031 if (initStyle == CXXNewExpr::CallInit) { 1032 if (ParenListExpr *List = dyn_cast<ParenListExpr>(Initializer)) { 1033 Inits = List->getExprs(); 1034 NumInits = List->getNumExprs(); 1035 } else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Initializer)){ 1036 if (!isa<CXXTemporaryObjectExpr>(CCE)) { 1037 // Can happen in template instantiation. Since this is just an implicit 1038 // construction, we just take it apart and rebuild it. 1039 Inits = CCE->getArgs(); 1040 NumInits = CCE->getNumArgs(); 1041 } 1042 } 1043 } 1044 1045 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 1046 if (TypeMayContainAuto && AllocType->getContainedAutoType()) { 1047 if (initStyle == CXXNewExpr::NoInit || NumInits == 0) 1048 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg) 1049 << AllocType << TypeRange); 1050 if (initStyle == CXXNewExpr::ListInit) 1051 return ExprError(Diag(Inits[0]->getSourceRange().getBegin(), 1052 diag::err_auto_new_requires_parens) 1053 << AllocType << TypeRange); 1054 if (NumInits > 1) { 1055 Expr *FirstBad = Inits[1]; 1056 return ExprError(Diag(FirstBad->getSourceRange().getBegin(), 1057 diag::err_auto_new_ctor_multiple_expressions) 1058 << AllocType << TypeRange); 1059 } 1060 Expr *Deduce = Inits[0]; 1061 TypeSourceInfo *DeducedType = 0; 1062 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == 1063 DAR_Failed) 1064 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure) 1065 << AllocType << Deduce->getType() 1066 << TypeRange << Deduce->getSourceRange()); 1067 if (!DeducedType) 1068 return ExprError(); 1069 1070 AllocTypeInfo = DeducedType; 1071 AllocType = AllocTypeInfo->getType(); 1072 } 1073 1074 // Per C++0x [expr.new]p5, the type being constructed may be a 1075 // typedef of an array type. 1076 if (!ArraySize) { 1077 if (const ConstantArrayType *Array 1078 = Context.getAsConstantArrayType(AllocType)) { 1079 ArraySize = IntegerLiteral::Create(Context, Array->getSize(), 1080 Context.getSizeType(), 1081 TypeRange.getEnd()); 1082 AllocType = Array->getElementType(); 1083 } 1084 } 1085 1086 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange)) 1087 return ExprError(); 1088 1089 if (initStyle == CXXNewExpr::ListInit && isStdInitializerList(AllocType, 0)) { 1090 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(), 1091 diag::warn_dangling_std_initializer_list) 1092 << /*at end of FE*/0 << Inits[0]->getSourceRange(); 1093 } 1094 1095 // In ARC, infer 'retaining' for the allocated 1096 if (getLangOptions().ObjCAutoRefCount && 1097 AllocType.getObjCLifetime() == Qualifiers::OCL_None && 1098 AllocType->isObjCLifetimeType()) { 1099 AllocType = Context.getLifetimeQualifiedType(AllocType, 1100 AllocType->getObjCARCImplicitLifetime()); 1101 } 1102 1103 QualType ResultType = Context.getPointerType(AllocType); 1104 1105 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have 1106 // integral or enumeration type with a non-negative value." 1107 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped 1108 // enumeration type, or a class type for which a single non-explicit 1109 // conversion function to integral or unscoped enumeration type exists. 1110 if (ArraySize && !ArraySize->isTypeDependent()) { 1111 ExprResult ConvertedSize = ConvertToIntegralOrEnumerationType( 1112 StartLoc, ArraySize, 1113 PDiag(diag::err_array_size_not_integral) << getLangOptions().CPlusPlus0x, 1114 PDiag(diag::err_array_size_incomplete_type) 1115 << ArraySize->getSourceRange(), 1116 PDiag(diag::err_array_size_explicit_conversion), 1117 PDiag(diag::note_array_size_conversion), 1118 PDiag(diag::err_array_size_ambiguous_conversion), 1119 PDiag(diag::note_array_size_conversion), 1120 PDiag(getLangOptions().CPlusPlus0x ? 1121 diag::warn_cxx98_compat_array_size_conversion : 1122 diag::ext_array_size_conversion), 1123 /*AllowScopedEnumerations*/ false); 1124 if (ConvertedSize.isInvalid()) 1125 return ExprError(); 1126 1127 ArraySize = ConvertedSize.take(); 1128 QualType SizeType = ArraySize->getType(); 1129 if (!SizeType->isIntegralOrUnscopedEnumerationType()) 1130 return ExprError(); 1131 1132 // C++98 [expr.new]p7: 1133 // The expression in a direct-new-declarator shall have integral type 1134 // with a non-negative value. 1135 // 1136 // Let's see if this is a constant < 0. If so, we reject it out of 1137 // hand. Otherwise, if it's not a constant, we must have an unparenthesized 1138 // array type. 1139 // 1140 // Note: such a construct has well-defined semantics in C++11: it throws 1141 // std::bad_array_new_length. 1142 if (!ArraySize->isValueDependent()) { 1143 llvm::APSInt Value; 1144 // We've already performed any required implicit conversion to integer or 1145 // unscoped enumeration type. 1146 if (ArraySize->isIntegerConstantExpr(Value, Context)) { 1147 if (Value < llvm::APSInt( 1148 llvm::APInt::getNullValue(Value.getBitWidth()), 1149 Value.isUnsigned())) { 1150 if (getLangOptions().CPlusPlus0x) 1151 Diag(ArraySize->getSourceRange().getBegin(), 1152 diag::warn_typecheck_negative_array_new_size) 1153 << ArraySize->getSourceRange(); 1154 else 1155 return ExprError(Diag(ArraySize->getSourceRange().getBegin(), 1156 diag::err_typecheck_negative_array_size) 1157 << ArraySize->getSourceRange()); 1158 } else if (!AllocType->isDependentType()) { 1159 unsigned ActiveSizeBits = 1160 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value); 1161 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 1162 if (getLangOptions().CPlusPlus0x) 1163 Diag(ArraySize->getSourceRange().getBegin(), 1164 diag::warn_array_new_too_large) 1165 << Value.toString(10) 1166 << ArraySize->getSourceRange(); 1167 else 1168 return ExprError(Diag(ArraySize->getSourceRange().getBegin(), 1169 diag::err_array_too_large) 1170 << Value.toString(10) 1171 << ArraySize->getSourceRange()); 1172 } 1173 } 1174 } else if (TypeIdParens.isValid()) { 1175 // Can't have dynamic array size when the type-id is in parentheses. 1176 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst) 1177 << ArraySize->getSourceRange() 1178 << FixItHint::CreateRemoval(TypeIdParens.getBegin()) 1179 << FixItHint::CreateRemoval(TypeIdParens.getEnd()); 1180 1181 TypeIdParens = SourceRange(); 1182 } 1183 } 1184 1185 // ARC: warn about ABI issues. 1186 if (getLangOptions().ObjCAutoRefCount) { 1187 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1188 if (BaseAllocType.hasStrongOrWeakObjCLifetime()) 1189 Diag(StartLoc, diag::warn_err_new_delete_object_array) 1190 << 0 << BaseAllocType; 1191 } 1192 1193 // Note that we do *not* convert the argument in any way. It can 1194 // be signed, larger than size_t, whatever. 1195 } 1196 1197 FunctionDecl *OperatorNew = 0; 1198 FunctionDecl *OperatorDelete = 0; 1199 Expr **PlaceArgs = (Expr**)PlacementArgs.get(); 1200 unsigned NumPlaceArgs = PlacementArgs.size(); 1201 1202 if (!AllocType->isDependentType() && 1203 !Expr::hasAnyTypeDependentArguments(PlaceArgs, NumPlaceArgs) && 1204 FindAllocationFunctions(StartLoc, 1205 SourceRange(PlacementLParen, PlacementRParen), 1206 UseGlobal, AllocType, ArraySize, PlaceArgs, 1207 NumPlaceArgs, OperatorNew, OperatorDelete)) 1208 return ExprError(); 1209 1210 // If this is an array allocation, compute whether the usual array 1211 // deallocation function for the type has a size_t parameter. 1212 bool UsualArrayDeleteWantsSize = false; 1213 if (ArraySize && !AllocType->isDependentType()) 1214 UsualArrayDeleteWantsSize 1215 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType); 1216 1217 SmallVector<Expr *, 8> AllPlaceArgs; 1218 if (OperatorNew) { 1219 // Add default arguments, if any. 1220 const FunctionProtoType *Proto = 1221 OperatorNew->getType()->getAs<FunctionProtoType>(); 1222 VariadicCallType CallType = 1223 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 1224 1225 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, 1226 Proto, 1, PlaceArgs, NumPlaceArgs, 1227 AllPlaceArgs, CallType)) 1228 return ExprError(); 1229 1230 NumPlaceArgs = AllPlaceArgs.size(); 1231 if (NumPlaceArgs > 0) 1232 PlaceArgs = &AllPlaceArgs[0]; 1233 } 1234 1235 // Warn if the type is over-aligned and is being allocated by global operator 1236 // new. 1237 if (NumPlaceArgs == 0 && OperatorNew && 1238 (OperatorNew->isImplicit() || 1239 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1240 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1241 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1242 if (Align > SuitableAlign) 1243 Diag(StartLoc, diag::warn_overaligned_type) 1244 << AllocType 1245 << unsigned(Align / Context.getCharWidth()) 1246 << unsigned(SuitableAlign / Context.getCharWidth()); 1247 } 1248 } 1249 1250 QualType InitType = AllocType; 1251 // Array 'new' can't have any initializers except empty parentheses. 1252 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1253 // dialect distinction. 1254 if (ResultType->isArrayType() || ArraySize) { 1255 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1256 SourceRange InitRange(Inits[0]->getLocStart(), 1257 Inits[NumInits - 1]->getLocEnd()); 1258 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1259 return ExprError(); 1260 } 1261 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1262 // We do the initialization typechecking against the array type 1263 // corresponding to the number of initializers + 1 (to also check 1264 // default-initialization). 1265 unsigned NumElements = ILE->getNumInits() + 1; 1266 InitType = Context.getConstantArrayType(AllocType, 1267 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1268 ArrayType::Normal, 0); 1269 } 1270 } 1271 1272 if (!AllocType->isDependentType() && 1273 !Expr::hasAnyTypeDependentArguments(Inits, NumInits)) { 1274 // C++11 [expr.new]p15: 1275 // A new-expression that creates an object of type T initializes that 1276 // object as follows: 1277 InitializationKind Kind 1278 // - If the new-initializer is omitted, the object is default- 1279 // initialized (8.5); if no initialization is performed, 1280 // the object has indeterminate value 1281 = initStyle == CXXNewExpr::NoInit 1282 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1283 // - Otherwise, the new-initializer is interpreted according to the 1284 // initialization rules of 8.5 for direct-initialization. 1285 : initStyle == CXXNewExpr::ListInit 1286 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1287 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1288 DirectInitRange.getBegin(), 1289 DirectInitRange.getEnd()); 1290 1291 InitializedEntity Entity 1292 = InitializedEntity::InitializeNew(StartLoc, InitType); 1293 InitializationSequence InitSeq(*this, Entity, Kind, Inits, NumInits); 1294 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1295 MultiExprArg(Inits, NumInits)); 1296 if (FullInit.isInvalid()) 1297 return ExprError(); 1298 1299 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1300 // we don't want the initialized object to be destructed. 1301 if (CXXBindTemporaryExpr *Binder = 1302 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1303 FullInit = Owned(Binder->getSubExpr()); 1304 1305 Initializer = FullInit.take(); 1306 } 1307 1308 // Mark the new and delete operators as referenced. 1309 if (OperatorNew) 1310 MarkFunctionReferenced(StartLoc, OperatorNew); 1311 if (OperatorDelete) 1312 MarkFunctionReferenced(StartLoc, OperatorDelete); 1313 1314 // C++0x [expr.new]p17: 1315 // If the new expression creates an array of objects of class type, 1316 // access and ambiguity control are done for the destructor. 1317 if (ArraySize && AllocType->isRecordType() && !AllocType->isDependentType()) { 1318 if (CXXDestructorDecl *dtor = LookupDestructor( 1319 cast<CXXRecordDecl>(AllocType->getAs<RecordType>()->getDecl()))) { 1320 MarkFunctionReferenced(StartLoc, dtor); 1321 CheckDestructorAccess(StartLoc, dtor, 1322 PDiag(diag::err_access_dtor) 1323 << Context.getBaseElementType(AllocType)); 1324 } 1325 } 1326 1327 PlacementArgs.release(); 1328 1329 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1330 OperatorDelete, 1331 UsualArrayDeleteWantsSize, 1332 PlaceArgs, NumPlaceArgs, TypeIdParens, 1333 ArraySize, initStyle, Initializer, 1334 ResultType, AllocTypeInfo, 1335 StartLoc, DirectInitRange)); 1336} 1337 1338/// \brief Checks that a type is suitable as the allocated type 1339/// in a new-expression. 1340bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1341 SourceRange R) { 1342 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1343 // abstract class type or array thereof. 1344 if (AllocType->isFunctionType()) 1345 return Diag(Loc, diag::err_bad_new_type) 1346 << AllocType << 0 << R; 1347 else if (AllocType->isReferenceType()) 1348 return Diag(Loc, diag::err_bad_new_type) 1349 << AllocType << 1 << R; 1350 else if (!AllocType->isDependentType() && 1351 RequireCompleteType(Loc, AllocType, 1352 PDiag(diag::err_new_incomplete_type) 1353 << R)) 1354 return true; 1355 else if (RequireNonAbstractType(Loc, AllocType, 1356 diag::err_allocation_of_abstract_type)) 1357 return true; 1358 else if (AllocType->isVariablyModifiedType()) 1359 return Diag(Loc, diag::err_variably_modified_new_type) 1360 << AllocType; 1361 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1362 return Diag(Loc, diag::err_address_space_qualified_new) 1363 << AllocType.getUnqualifiedType() << AddressSpace; 1364 else if (getLangOptions().ObjCAutoRefCount) { 1365 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1366 QualType BaseAllocType = Context.getBaseElementType(AT); 1367 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1368 BaseAllocType->isObjCLifetimeType()) 1369 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1370 << BaseAllocType; 1371 } 1372 } 1373 1374 return false; 1375} 1376 1377/// \brief Determine whether the given function is a non-placement 1378/// deallocation function. 1379static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1380 if (FD->isInvalidDecl()) 1381 return false; 1382 1383 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1384 return Method->isUsualDeallocationFunction(); 1385 1386 return ((FD->getOverloadedOperator() == OO_Delete || 1387 FD->getOverloadedOperator() == OO_Array_Delete) && 1388 FD->getNumParams() == 1); 1389} 1390 1391/// FindAllocationFunctions - Finds the overloads of operator new and delete 1392/// that are appropriate for the allocation. 1393bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1394 bool UseGlobal, QualType AllocType, 1395 bool IsArray, Expr **PlaceArgs, 1396 unsigned NumPlaceArgs, 1397 FunctionDecl *&OperatorNew, 1398 FunctionDecl *&OperatorDelete) { 1399 // --- Choosing an allocation function --- 1400 // C++ 5.3.4p8 - 14 & 18 1401 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1402 // in the scope of the allocated class. 1403 // 2) If an array size is given, look for operator new[], else look for 1404 // operator new. 1405 // 3) The first argument is always size_t. Append the arguments from the 1406 // placement form. 1407 1408 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1409 // We don't care about the actual value of this argument. 1410 // FIXME: Should the Sema create the expression and embed it in the syntax 1411 // tree? Or should the consumer just recalculate the value? 1412 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1413 Context.getTargetInfo().getPointerWidth(0)), 1414 Context.getSizeType(), 1415 SourceLocation()); 1416 AllocArgs[0] = &Size; 1417 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1418 1419 // C++ [expr.new]p8: 1420 // If the allocated type is a non-array type, the allocation 1421 // function's name is operator new and the deallocation function's 1422 // name is operator delete. If the allocated type is an array 1423 // type, the allocation function's name is operator new[] and the 1424 // deallocation function's name is operator delete[]. 1425 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1426 IsArray ? OO_Array_New : OO_New); 1427 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1428 IsArray ? OO_Array_Delete : OO_Delete); 1429 1430 QualType AllocElemType = Context.getBaseElementType(AllocType); 1431 1432 if (AllocElemType->isRecordType() && !UseGlobal) { 1433 CXXRecordDecl *Record 1434 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1435 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1436 AllocArgs.size(), Record, /*AllowMissing=*/true, 1437 OperatorNew)) 1438 return true; 1439 } 1440 if (!OperatorNew) { 1441 // Didn't find a member overload. Look for a global one. 1442 DeclareGlobalNewDelete(); 1443 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1444 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1445 AllocArgs.size(), TUDecl, /*AllowMissing=*/false, 1446 OperatorNew)) 1447 return true; 1448 } 1449 1450 // We don't need an operator delete if we're running under 1451 // -fno-exceptions. 1452 if (!getLangOptions().Exceptions) { 1453 OperatorDelete = 0; 1454 return false; 1455 } 1456 1457 // FindAllocationOverload can change the passed in arguments, so we need to 1458 // copy them back. 1459 if (NumPlaceArgs > 0) 1460 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1461 1462 // C++ [expr.new]p19: 1463 // 1464 // If the new-expression begins with a unary :: operator, the 1465 // deallocation function's name is looked up in the global 1466 // scope. Otherwise, if the allocated type is a class type T or an 1467 // array thereof, the deallocation function's name is looked up in 1468 // the scope of T. If this lookup fails to find the name, or if 1469 // the allocated type is not a class type or array thereof, the 1470 // deallocation function's name is looked up in the global scope. 1471 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1472 if (AllocElemType->isRecordType() && !UseGlobal) { 1473 CXXRecordDecl *RD 1474 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1475 LookupQualifiedName(FoundDelete, RD); 1476 } 1477 if (FoundDelete.isAmbiguous()) 1478 return true; // FIXME: clean up expressions? 1479 1480 if (FoundDelete.empty()) { 1481 DeclareGlobalNewDelete(); 1482 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1483 } 1484 1485 FoundDelete.suppressDiagnostics(); 1486 1487 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1488 1489 // Whether we're looking for a placement operator delete is dictated 1490 // by whether we selected a placement operator new, not by whether 1491 // we had explicit placement arguments. This matters for things like 1492 // struct A { void *operator new(size_t, int = 0); ... }; 1493 // A *a = new A() 1494 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1495 1496 if (isPlacementNew) { 1497 // C++ [expr.new]p20: 1498 // A declaration of a placement deallocation function matches the 1499 // declaration of a placement allocation function if it has the 1500 // same number of parameters and, after parameter transformations 1501 // (8.3.5), all parameter types except the first are 1502 // identical. [...] 1503 // 1504 // To perform this comparison, we compute the function type that 1505 // the deallocation function should have, and use that type both 1506 // for template argument deduction and for comparison purposes. 1507 // 1508 // FIXME: this comparison should ignore CC and the like. 1509 QualType ExpectedFunctionType; 1510 { 1511 const FunctionProtoType *Proto 1512 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1513 1514 SmallVector<QualType, 4> ArgTypes; 1515 ArgTypes.push_back(Context.VoidPtrTy); 1516 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1517 ArgTypes.push_back(Proto->getArgType(I)); 1518 1519 FunctionProtoType::ExtProtoInfo EPI; 1520 EPI.Variadic = Proto->isVariadic(); 1521 1522 ExpectedFunctionType 1523 = Context.getFunctionType(Context.VoidTy, ArgTypes.data(), 1524 ArgTypes.size(), EPI); 1525 } 1526 1527 for (LookupResult::iterator D = FoundDelete.begin(), 1528 DEnd = FoundDelete.end(); 1529 D != DEnd; ++D) { 1530 FunctionDecl *Fn = 0; 1531 if (FunctionTemplateDecl *FnTmpl 1532 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1533 // Perform template argument deduction to try to match the 1534 // expected function type. 1535 TemplateDeductionInfo Info(Context, StartLoc); 1536 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1537 continue; 1538 } else 1539 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1540 1541 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1542 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1543 } 1544 } else { 1545 // C++ [expr.new]p20: 1546 // [...] Any non-placement deallocation function matches a 1547 // non-placement allocation function. [...] 1548 for (LookupResult::iterator D = FoundDelete.begin(), 1549 DEnd = FoundDelete.end(); 1550 D != DEnd; ++D) { 1551 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1552 if (isNonPlacementDeallocationFunction(Fn)) 1553 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1554 } 1555 } 1556 1557 // C++ [expr.new]p20: 1558 // [...] If the lookup finds a single matching deallocation 1559 // function, that function will be called; otherwise, no 1560 // deallocation function will be called. 1561 if (Matches.size() == 1) { 1562 OperatorDelete = Matches[0].second; 1563 1564 // C++0x [expr.new]p20: 1565 // If the lookup finds the two-parameter form of a usual 1566 // deallocation function (3.7.4.2) and that function, considered 1567 // as a placement deallocation function, would have been 1568 // selected as a match for the allocation function, the program 1569 // is ill-formed. 1570 if (NumPlaceArgs && getLangOptions().CPlusPlus0x && 1571 isNonPlacementDeallocationFunction(OperatorDelete)) { 1572 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1573 << SourceRange(PlaceArgs[0]->getLocStart(), 1574 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1575 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1576 << DeleteName; 1577 } else { 1578 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1579 Matches[0].first); 1580 } 1581 } 1582 1583 return false; 1584} 1585 1586/// FindAllocationOverload - Find an fitting overload for the allocation 1587/// function in the specified scope. 1588bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1589 DeclarationName Name, Expr** Args, 1590 unsigned NumArgs, DeclContext *Ctx, 1591 bool AllowMissing, FunctionDecl *&Operator, 1592 bool Diagnose) { 1593 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1594 LookupQualifiedName(R, Ctx); 1595 if (R.empty()) { 1596 if (AllowMissing || !Diagnose) 1597 return false; 1598 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1599 << Name << Range; 1600 } 1601 1602 if (R.isAmbiguous()) 1603 return true; 1604 1605 R.suppressDiagnostics(); 1606 1607 OverloadCandidateSet Candidates(StartLoc); 1608 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1609 Alloc != AllocEnd; ++Alloc) { 1610 // Even member operator new/delete are implicitly treated as 1611 // static, so don't use AddMemberCandidate. 1612 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1613 1614 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1615 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1616 /*ExplicitTemplateArgs=*/0, Args, NumArgs, 1617 Candidates, 1618 /*SuppressUserConversions=*/false); 1619 continue; 1620 } 1621 1622 FunctionDecl *Fn = cast<FunctionDecl>(D); 1623 AddOverloadCandidate(Fn, Alloc.getPair(), Args, NumArgs, Candidates, 1624 /*SuppressUserConversions=*/false); 1625 } 1626 1627 // Do the resolution. 1628 OverloadCandidateSet::iterator Best; 1629 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1630 case OR_Success: { 1631 // Got one! 1632 FunctionDecl *FnDecl = Best->Function; 1633 MarkFunctionReferenced(StartLoc, FnDecl); 1634 // The first argument is size_t, and the first parameter must be size_t, 1635 // too. This is checked on declaration and can be assumed. (It can't be 1636 // asserted on, though, since invalid decls are left in there.) 1637 // Watch out for variadic allocator function. 1638 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1639 for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) { 1640 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1641 FnDecl->getParamDecl(i)); 1642 1643 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1644 return true; 1645 1646 ExprResult Result 1647 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1648 if (Result.isInvalid()) 1649 return true; 1650 1651 Args[i] = Result.takeAs<Expr>(); 1652 } 1653 Operator = FnDecl; 1654 CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), Best->FoundDecl, 1655 Diagnose); 1656 return false; 1657 } 1658 1659 case OR_No_Viable_Function: 1660 if (Diagnose) { 1661 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1662 << Name << Range; 1663 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 1664 } 1665 return true; 1666 1667 case OR_Ambiguous: 1668 if (Diagnose) { 1669 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1670 << Name << Range; 1671 Candidates.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 1672 } 1673 return true; 1674 1675 case OR_Deleted: { 1676 if (Diagnose) { 1677 Diag(StartLoc, diag::err_ovl_deleted_call) 1678 << Best->Function->isDeleted() 1679 << Name 1680 << getDeletedOrUnavailableSuffix(Best->Function) 1681 << Range; 1682 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 1683 } 1684 return true; 1685 } 1686 } 1687 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1688} 1689 1690 1691/// DeclareGlobalNewDelete - Declare the global forms of operator new and 1692/// delete. These are: 1693/// @code 1694/// // C++03: 1695/// void* operator new(std::size_t) throw(std::bad_alloc); 1696/// void* operator new[](std::size_t) throw(std::bad_alloc); 1697/// void operator delete(void *) throw(); 1698/// void operator delete[](void *) throw(); 1699/// // C++0x: 1700/// void* operator new(std::size_t); 1701/// void* operator new[](std::size_t); 1702/// void operator delete(void *); 1703/// void operator delete[](void *); 1704/// @endcode 1705/// C++0x operator delete is implicitly noexcept. 1706/// Note that the placement and nothrow forms of new are *not* implicitly 1707/// declared. Their use requires including \<new\>. 1708void Sema::DeclareGlobalNewDelete() { 1709 if (GlobalNewDeleteDeclared) 1710 return; 1711 1712 // C++ [basic.std.dynamic]p2: 1713 // [...] The following allocation and deallocation functions (18.4) are 1714 // implicitly declared in global scope in each translation unit of a 1715 // program 1716 // 1717 // C++03: 1718 // void* operator new(std::size_t) throw(std::bad_alloc); 1719 // void* operator new[](std::size_t) throw(std::bad_alloc); 1720 // void operator delete(void*) throw(); 1721 // void operator delete[](void*) throw(); 1722 // C++0x: 1723 // void* operator new(std::size_t); 1724 // void* operator new[](std::size_t); 1725 // void operator delete(void*); 1726 // void operator delete[](void*); 1727 // 1728 // These implicit declarations introduce only the function names operator 1729 // new, operator new[], operator delete, operator delete[]. 1730 // 1731 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1732 // "std" or "bad_alloc" as necessary to form the exception specification. 1733 // However, we do not make these implicit declarations visible to name 1734 // lookup. 1735 // Note that the C++0x versions of operator delete are deallocation functions, 1736 // and thus are implicitly noexcept. 1737 if (!StdBadAlloc && !getLangOptions().CPlusPlus0x) { 1738 // The "std::bad_alloc" class has not yet been declared, so build it 1739 // implicitly. 1740 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1741 getOrCreateStdNamespace(), 1742 SourceLocation(), SourceLocation(), 1743 &PP.getIdentifierTable().get("bad_alloc"), 1744 0); 1745 getStdBadAlloc()->setImplicit(true); 1746 } 1747 1748 GlobalNewDeleteDeclared = true; 1749 1750 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1751 QualType SizeT = Context.getSizeType(); 1752 bool AssumeSaneOperatorNew = getLangOptions().AssumeSaneOperatorNew; 1753 1754 DeclareGlobalAllocationFunction( 1755 Context.DeclarationNames.getCXXOperatorName(OO_New), 1756 VoidPtr, SizeT, AssumeSaneOperatorNew); 1757 DeclareGlobalAllocationFunction( 1758 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1759 VoidPtr, SizeT, AssumeSaneOperatorNew); 1760 DeclareGlobalAllocationFunction( 1761 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1762 Context.VoidTy, VoidPtr); 1763 DeclareGlobalAllocationFunction( 1764 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1765 Context.VoidTy, VoidPtr); 1766} 1767 1768/// DeclareGlobalAllocationFunction - Declares a single implicit global 1769/// allocation function if it doesn't already exist. 1770void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1771 QualType Return, QualType Argument, 1772 bool AddMallocAttr) { 1773 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1774 1775 // Check if this function is already declared. 1776 { 1777 DeclContext::lookup_iterator Alloc, AllocEnd; 1778 for (llvm::tie(Alloc, AllocEnd) = GlobalCtx->lookup(Name); 1779 Alloc != AllocEnd; ++Alloc) { 1780 // Only look at non-template functions, as it is the predefined, 1781 // non-templated allocation function we are trying to declare here. 1782 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1783 QualType InitialParamType = 1784 Context.getCanonicalType( 1785 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1786 // FIXME: Do we need to check for default arguments here? 1787 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1788 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1789 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1790 return; 1791 } 1792 } 1793 } 1794 } 1795 1796 QualType BadAllocType; 1797 bool HasBadAllocExceptionSpec 1798 = (Name.getCXXOverloadedOperator() == OO_New || 1799 Name.getCXXOverloadedOperator() == OO_Array_New); 1800 if (HasBadAllocExceptionSpec && !getLangOptions().CPlusPlus0x) { 1801 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1802 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1803 } 1804 1805 FunctionProtoType::ExtProtoInfo EPI; 1806 if (HasBadAllocExceptionSpec) { 1807 if (!getLangOptions().CPlusPlus0x) { 1808 EPI.ExceptionSpecType = EST_Dynamic; 1809 EPI.NumExceptions = 1; 1810 EPI.Exceptions = &BadAllocType; 1811 } 1812 } else { 1813 EPI.ExceptionSpecType = getLangOptions().CPlusPlus0x ? 1814 EST_BasicNoexcept : EST_DynamicNone; 1815 } 1816 1817 QualType FnType = Context.getFunctionType(Return, &Argument, 1, EPI); 1818 FunctionDecl *Alloc = 1819 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1820 SourceLocation(), Name, 1821 FnType, /*TInfo=*/0, SC_None, 1822 SC_None, false, true); 1823 Alloc->setImplicit(); 1824 1825 if (AddMallocAttr) 1826 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1827 1828 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1829 SourceLocation(), 0, 1830 Argument, /*TInfo=*/0, 1831 SC_None, SC_None, 0); 1832 Alloc->setParams(Param); 1833 1834 // FIXME: Also add this declaration to the IdentifierResolver, but 1835 // make sure it is at the end of the chain to coincide with the 1836 // global scope. 1837 Context.getTranslationUnitDecl()->addDecl(Alloc); 1838} 1839 1840bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1841 DeclarationName Name, 1842 FunctionDecl* &Operator, bool Diagnose) { 1843 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1844 // Try to find operator delete/operator delete[] in class scope. 1845 LookupQualifiedName(Found, RD); 1846 1847 if (Found.isAmbiguous()) 1848 return true; 1849 1850 Found.suppressDiagnostics(); 1851 1852 SmallVector<DeclAccessPair,4> Matches; 1853 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1854 F != FEnd; ++F) { 1855 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1856 1857 // Ignore template operator delete members from the check for a usual 1858 // deallocation function. 1859 if (isa<FunctionTemplateDecl>(ND)) 1860 continue; 1861 1862 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1863 Matches.push_back(F.getPair()); 1864 } 1865 1866 // There's exactly one suitable operator; pick it. 1867 if (Matches.size() == 1) { 1868 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 1869 1870 if (Operator->isDeleted()) { 1871 if (Diagnose) { 1872 Diag(StartLoc, diag::err_deleted_function_use); 1873 Diag(Operator->getLocation(), diag::note_unavailable_here) << true; 1874 } 1875 return true; 1876 } 1877 1878 CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 1879 Matches[0], Diagnose); 1880 return false; 1881 1882 // We found multiple suitable operators; complain about the ambiguity. 1883 } else if (!Matches.empty()) { 1884 if (Diagnose) { 1885 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 1886 << Name << RD; 1887 1888 for (SmallVectorImpl<DeclAccessPair>::iterator 1889 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 1890 Diag((*F)->getUnderlyingDecl()->getLocation(), 1891 diag::note_member_declared_here) << Name; 1892 } 1893 return true; 1894 } 1895 1896 // We did find operator delete/operator delete[] declarations, but 1897 // none of them were suitable. 1898 if (!Found.empty()) { 1899 if (Diagnose) { 1900 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 1901 << Name << RD; 1902 1903 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1904 F != FEnd; ++F) 1905 Diag((*F)->getUnderlyingDecl()->getLocation(), 1906 diag::note_member_declared_here) << Name; 1907 } 1908 return true; 1909 } 1910 1911 // Look for a global declaration. 1912 DeclareGlobalNewDelete(); 1913 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1914 1915 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 1916 Expr* DeallocArgs[1]; 1917 DeallocArgs[0] = &Null; 1918 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 1919 DeallocArgs, 1, TUDecl, !Diagnose, 1920 Operator, Diagnose)) 1921 return true; 1922 1923 assert(Operator && "Did not find a deallocation function!"); 1924 return false; 1925} 1926 1927/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 1928/// @code ::delete ptr; @endcode 1929/// or 1930/// @code delete [] ptr; @endcode 1931ExprResult 1932Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 1933 bool ArrayForm, Expr *ExE) { 1934 // C++ [expr.delete]p1: 1935 // The operand shall have a pointer type, or a class type having a single 1936 // conversion function to a pointer type. The result has type void. 1937 // 1938 // DR599 amends "pointer type" to "pointer to object type" in both cases. 1939 1940 ExprResult Ex = Owned(ExE); 1941 FunctionDecl *OperatorDelete = 0; 1942 bool ArrayFormAsWritten = ArrayForm; 1943 bool UsualArrayDeleteWantsSize = false; 1944 1945 if (!Ex.get()->isTypeDependent()) { 1946 QualType Type = Ex.get()->getType(); 1947 1948 if (const RecordType *Record = Type->getAs<RecordType>()) { 1949 if (RequireCompleteType(StartLoc, Type, 1950 PDiag(diag::err_delete_incomplete_class_type))) 1951 return ExprError(); 1952 1953 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 1954 1955 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 1956 const UnresolvedSetImpl *Conversions = RD->getVisibleConversionFunctions(); 1957 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 1958 E = Conversions->end(); I != E; ++I) { 1959 NamedDecl *D = I.getDecl(); 1960 if (isa<UsingShadowDecl>(D)) 1961 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1962 1963 // Skip over templated conversion functions; they aren't considered. 1964 if (isa<FunctionTemplateDecl>(D)) 1965 continue; 1966 1967 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 1968 1969 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 1970 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 1971 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 1972 ObjectPtrConversions.push_back(Conv); 1973 } 1974 if (ObjectPtrConversions.size() == 1) { 1975 // We have a single conversion to a pointer-to-object type. Perform 1976 // that conversion. 1977 // TODO: don't redo the conversion calculation. 1978 ExprResult Res = 1979 PerformImplicitConversion(Ex.get(), 1980 ObjectPtrConversions.front()->getConversionType(), 1981 AA_Converting); 1982 if (Res.isUsable()) { 1983 Ex = move(Res); 1984 Type = Ex.get()->getType(); 1985 } 1986 } 1987 else if (ObjectPtrConversions.size() > 1) { 1988 Diag(StartLoc, diag::err_ambiguous_delete_operand) 1989 << Type << Ex.get()->getSourceRange(); 1990 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 1991 NoteOverloadCandidate(ObjectPtrConversions[i]); 1992 return ExprError(); 1993 } 1994 } 1995 1996 if (!Type->isPointerType()) 1997 return ExprError(Diag(StartLoc, diag::err_delete_operand) 1998 << Type << Ex.get()->getSourceRange()); 1999 2000 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2001 QualType PointeeElem = Context.getBaseElementType(Pointee); 2002 2003 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2004 return Diag(Ex.get()->getLocStart(), 2005 diag::err_address_space_qualified_delete) 2006 << Pointee.getUnqualifiedType() << AddressSpace; 2007 2008 CXXRecordDecl *PointeeRD = 0; 2009 if (Pointee->isVoidType() && !isSFINAEContext()) { 2010 // The C++ standard bans deleting a pointer to a non-object type, which 2011 // effectively bans deletion of "void*". However, most compilers support 2012 // this, so we treat it as a warning unless we're in a SFINAE context. 2013 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2014 << Type << Ex.get()->getSourceRange(); 2015 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2016 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2017 << Type << Ex.get()->getSourceRange()); 2018 } else if (!Pointee->isDependentType()) { 2019 if (!RequireCompleteType(StartLoc, Pointee, 2020 PDiag(diag::warn_delete_incomplete) 2021 << Ex.get()->getSourceRange())) { 2022 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2023 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2024 } 2025 } 2026 2027 // Perform lvalue-to-rvalue cast, if needed. 2028 Ex = DefaultLvalueConversion(Ex.take()); 2029 2030 // C++ [expr.delete]p2: 2031 // [Note: a pointer to a const type can be the operand of a 2032 // delete-expression; it is not necessary to cast away the constness 2033 // (5.2.11) of the pointer expression before it is used as the operand 2034 // of the delete-expression. ] 2035 if (!Context.hasSameType(Ex.get()->getType(), Context.VoidPtrTy)) 2036 Ex = Owned(ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2037 CK_BitCast, Ex.take(), 0, VK_RValue)); 2038 2039 if (Pointee->isArrayType() && !ArrayForm) { 2040 Diag(StartLoc, diag::warn_delete_array_type) 2041 << Type << Ex.get()->getSourceRange() 2042 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2043 ArrayForm = true; 2044 } 2045 2046 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2047 ArrayForm ? OO_Array_Delete : OO_Delete); 2048 2049 if (PointeeRD) { 2050 if (!UseGlobal && 2051 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2052 OperatorDelete)) 2053 return ExprError(); 2054 2055 // If we're allocating an array of records, check whether the 2056 // usual operator delete[] has a size_t parameter. 2057 if (ArrayForm) { 2058 // If the user specifically asked to use the global allocator, 2059 // we'll need to do the lookup into the class. 2060 if (UseGlobal) 2061 UsualArrayDeleteWantsSize = 2062 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2063 2064 // Otherwise, the usual operator delete[] should be the 2065 // function we just found. 2066 else if (isa<CXXMethodDecl>(OperatorDelete)) 2067 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2068 } 2069 2070 if (!PointeeRD->hasTrivialDestructor()) 2071 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2072 MarkFunctionReferenced(StartLoc, 2073 const_cast<CXXDestructorDecl*>(Dtor)); 2074 DiagnoseUseOfDecl(Dtor, StartLoc); 2075 } 2076 2077 // C++ [expr.delete]p3: 2078 // In the first alternative (delete object), if the static type of the 2079 // object to be deleted is different from its dynamic type, the static 2080 // type shall be a base class of the dynamic type of the object to be 2081 // deleted and the static type shall have a virtual destructor or the 2082 // behavior is undefined. 2083 // 2084 // Note: a final class cannot be derived from, no issue there 2085 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2086 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2087 if (dtor && !dtor->isVirtual()) { 2088 if (PointeeRD->isAbstract()) { 2089 // If the class is abstract, we warn by default, because we're 2090 // sure the code has undefined behavior. 2091 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2092 << PointeeElem; 2093 } else if (!ArrayForm) { 2094 // Otherwise, if this is not an array delete, it's a bit suspect, 2095 // but not necessarily wrong. 2096 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2097 } 2098 } 2099 } 2100 2101 } else if (getLangOptions().ObjCAutoRefCount && 2102 PointeeElem->isObjCLifetimeType() && 2103 (PointeeElem.getObjCLifetime() == Qualifiers::OCL_Strong || 2104 PointeeElem.getObjCLifetime() == Qualifiers::OCL_Weak) && 2105 ArrayForm) { 2106 Diag(StartLoc, diag::warn_err_new_delete_object_array) 2107 << 1 << PointeeElem; 2108 } 2109 2110 if (!OperatorDelete) { 2111 // Look for a global declaration. 2112 DeclareGlobalNewDelete(); 2113 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2114 Expr *Arg = Ex.get(); 2115 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2116 &Arg, 1, TUDecl, /*AllowMissing=*/false, 2117 OperatorDelete)) 2118 return ExprError(); 2119 } 2120 2121 MarkFunctionReferenced(StartLoc, OperatorDelete); 2122 2123 // Check access and ambiguity of operator delete and destructor. 2124 if (PointeeRD) { 2125 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2126 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2127 PDiag(diag::err_access_dtor) << PointeeElem); 2128 } 2129 } 2130 2131 } 2132 2133 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2134 ArrayFormAsWritten, 2135 UsualArrayDeleteWantsSize, 2136 OperatorDelete, Ex.take(), StartLoc)); 2137} 2138 2139/// \brief Check the use of the given variable as a C++ condition in an if, 2140/// while, do-while, or switch statement. 2141ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2142 SourceLocation StmtLoc, 2143 bool ConvertToBoolean) { 2144 QualType T = ConditionVar->getType(); 2145 2146 // C++ [stmt.select]p2: 2147 // The declarator shall not specify a function or an array. 2148 if (T->isFunctionType()) 2149 return ExprError(Diag(ConditionVar->getLocation(), 2150 diag::err_invalid_use_of_function_type) 2151 << ConditionVar->getSourceRange()); 2152 else if (T->isArrayType()) 2153 return ExprError(Diag(ConditionVar->getLocation(), 2154 diag::err_invalid_use_of_array_type) 2155 << ConditionVar->getSourceRange()); 2156 2157 ExprResult Condition = 2158 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2159 SourceLocation(), 2160 ConditionVar, 2161 ConditionVar->getLocation(), 2162 ConditionVar->getType().getNonReferenceType(), 2163 VK_LValue)); 2164 2165 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2166 2167 if (ConvertToBoolean) { 2168 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2169 if (Condition.isInvalid()) 2170 return ExprError(); 2171 } 2172 2173 return move(Condition); 2174} 2175 2176/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2177ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2178 // C++ 6.4p4: 2179 // The value of a condition that is an initialized declaration in a statement 2180 // other than a switch statement is the value of the declared variable 2181 // implicitly converted to type bool. If that conversion is ill-formed, the 2182 // program is ill-formed. 2183 // The value of a condition that is an expression is the value of the 2184 // expression, implicitly converted to bool. 2185 // 2186 return PerformContextuallyConvertToBool(CondExpr); 2187} 2188 2189/// Helper function to determine whether this is the (deprecated) C++ 2190/// conversion from a string literal to a pointer to non-const char or 2191/// non-const wchar_t (for narrow and wide string literals, 2192/// respectively). 2193bool 2194Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2195 // Look inside the implicit cast, if it exists. 2196 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2197 From = Cast->getSubExpr(); 2198 2199 // A string literal (2.13.4) that is not a wide string literal can 2200 // be converted to an rvalue of type "pointer to char"; a wide 2201 // string literal can be converted to an rvalue of type "pointer 2202 // to wchar_t" (C++ 4.2p2). 2203 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2204 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2205 if (const BuiltinType *ToPointeeType 2206 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2207 // This conversion is considered only when there is an 2208 // explicit appropriate pointer target type (C++ 4.2p2). 2209 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2210 switch (StrLit->getKind()) { 2211 case StringLiteral::UTF8: 2212 case StringLiteral::UTF16: 2213 case StringLiteral::UTF32: 2214 // We don't allow UTF literals to be implicitly converted 2215 break; 2216 case StringLiteral::Ascii: 2217 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2218 ToPointeeType->getKind() == BuiltinType::Char_S); 2219 case StringLiteral::Wide: 2220 return ToPointeeType->isWideCharType(); 2221 } 2222 } 2223 } 2224 2225 return false; 2226} 2227 2228static ExprResult BuildCXXCastArgument(Sema &S, 2229 SourceLocation CastLoc, 2230 QualType Ty, 2231 CastKind Kind, 2232 CXXMethodDecl *Method, 2233 DeclAccessPair FoundDecl, 2234 bool HadMultipleCandidates, 2235 Expr *From) { 2236 switch (Kind) { 2237 default: llvm_unreachable("Unhandled cast kind!"); 2238 case CK_ConstructorConversion: { 2239 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2240 ASTOwningVector<Expr*> ConstructorArgs(S); 2241 2242 if (S.CompleteConstructorCall(Constructor, 2243 MultiExprArg(&From, 1), 2244 CastLoc, ConstructorArgs)) 2245 return ExprError(); 2246 2247 S.CheckConstructorAccess(CastLoc, Constructor, Constructor->getAccess(), 2248 S.PDiag(diag::err_access_ctor)); 2249 2250 ExprResult Result 2251 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2252 move_arg(ConstructorArgs), 2253 HadMultipleCandidates, /*ZeroInit*/ false, 2254 CXXConstructExpr::CK_Complete, SourceRange()); 2255 if (Result.isInvalid()) 2256 return ExprError(); 2257 2258 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2259 } 2260 2261 case CK_UserDefinedConversion: { 2262 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2263 2264 // Create an implicit call expr that calls it. 2265 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Method, 2266 HadMultipleCandidates); 2267 if (Result.isInvalid()) 2268 return ExprError(); 2269 // Record usage of conversion in an implicit cast. 2270 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2271 Result.get()->getType(), 2272 CK_UserDefinedConversion, 2273 Result.get(), 0, 2274 Result.get()->getValueKind())); 2275 2276 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2277 2278 return S.MaybeBindToTemporary(Result.get()); 2279 } 2280 } 2281} 2282 2283/// PerformImplicitConversion - Perform an implicit conversion of the 2284/// expression From to the type ToType using the pre-computed implicit 2285/// conversion sequence ICS. Returns the converted 2286/// expression. Action is the kind of conversion we're performing, 2287/// used in the error message. 2288ExprResult 2289Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2290 const ImplicitConversionSequence &ICS, 2291 AssignmentAction Action, 2292 CheckedConversionKind CCK) { 2293 switch (ICS.getKind()) { 2294 case ImplicitConversionSequence::StandardConversion: { 2295 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2296 Action, CCK); 2297 if (Res.isInvalid()) 2298 return ExprError(); 2299 From = Res.take(); 2300 break; 2301 } 2302 2303 case ImplicitConversionSequence::UserDefinedConversion: { 2304 2305 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2306 CastKind CastKind; 2307 QualType BeforeToType; 2308 assert(FD && "FIXME: aggregate initialization from init list"); 2309 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2310 CastKind = CK_UserDefinedConversion; 2311 2312 // If the user-defined conversion is specified by a conversion function, 2313 // the initial standard conversion sequence converts the source type to 2314 // the implicit object parameter of the conversion function. 2315 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2316 } else { 2317 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2318 CastKind = CK_ConstructorConversion; 2319 // Do no conversion if dealing with ... for the first conversion. 2320 if (!ICS.UserDefined.EllipsisConversion) { 2321 // If the user-defined conversion is specified by a constructor, the 2322 // initial standard conversion sequence converts the source type to the 2323 // type required by the argument of the constructor 2324 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2325 } 2326 } 2327 // Watch out for elipsis conversion. 2328 if (!ICS.UserDefined.EllipsisConversion) { 2329 ExprResult Res = 2330 PerformImplicitConversion(From, BeforeToType, 2331 ICS.UserDefined.Before, AA_Converting, 2332 CCK); 2333 if (Res.isInvalid()) 2334 return ExprError(); 2335 From = Res.take(); 2336 } 2337 2338 ExprResult CastArg 2339 = BuildCXXCastArgument(*this, 2340 From->getLocStart(), 2341 ToType.getNonReferenceType(), 2342 CastKind, cast<CXXMethodDecl>(FD), 2343 ICS.UserDefined.FoundConversionFunction, 2344 ICS.UserDefined.HadMultipleCandidates, 2345 From); 2346 2347 if (CastArg.isInvalid()) 2348 return ExprError(); 2349 2350 From = CastArg.take(); 2351 2352 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2353 AA_Converting, CCK); 2354 } 2355 2356 case ImplicitConversionSequence::AmbiguousConversion: 2357 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2358 PDiag(diag::err_typecheck_ambiguous_condition) 2359 << From->getSourceRange()); 2360 return ExprError(); 2361 2362 case ImplicitConversionSequence::EllipsisConversion: 2363 llvm_unreachable("Cannot perform an ellipsis conversion"); 2364 2365 case ImplicitConversionSequence::BadConversion: 2366 return ExprError(); 2367 } 2368 2369 // Everything went well. 2370 return Owned(From); 2371} 2372 2373/// PerformImplicitConversion - Perform an implicit conversion of the 2374/// expression From to the type ToType by following the standard 2375/// conversion sequence SCS. Returns the converted 2376/// expression. Flavor is the context in which we're performing this 2377/// conversion, for use in error messages. 2378ExprResult 2379Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2380 const StandardConversionSequence& SCS, 2381 AssignmentAction Action, 2382 CheckedConversionKind CCK) { 2383 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2384 2385 // Overall FIXME: we are recomputing too many types here and doing far too 2386 // much extra work. What this means is that we need to keep track of more 2387 // information that is computed when we try the implicit conversion initially, 2388 // so that we don't need to recompute anything here. 2389 QualType FromType = From->getType(); 2390 2391 if (SCS.CopyConstructor) { 2392 // FIXME: When can ToType be a reference type? 2393 assert(!ToType->isReferenceType()); 2394 if (SCS.Second == ICK_Derived_To_Base) { 2395 ASTOwningVector<Expr*> ConstructorArgs(*this); 2396 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2397 MultiExprArg(*this, &From, 1), 2398 /*FIXME:ConstructLoc*/SourceLocation(), 2399 ConstructorArgs)) 2400 return ExprError(); 2401 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2402 ToType, SCS.CopyConstructor, 2403 move_arg(ConstructorArgs), 2404 /*HadMultipleCandidates*/ false, 2405 /*ZeroInit*/ false, 2406 CXXConstructExpr::CK_Complete, 2407 SourceRange()); 2408 } 2409 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2410 ToType, SCS.CopyConstructor, 2411 MultiExprArg(*this, &From, 1), 2412 /*HadMultipleCandidates*/ false, 2413 /*ZeroInit*/ false, 2414 CXXConstructExpr::CK_Complete, 2415 SourceRange()); 2416 } 2417 2418 // Resolve overloaded function references. 2419 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2420 DeclAccessPair Found; 2421 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2422 true, Found); 2423 if (!Fn) 2424 return ExprError(); 2425 2426 if (DiagnoseUseOfDecl(Fn, From->getSourceRange().getBegin())) 2427 return ExprError(); 2428 2429 From = FixOverloadedFunctionReference(From, Found, Fn); 2430 FromType = From->getType(); 2431 } 2432 2433 // Perform the first implicit conversion. 2434 switch (SCS.First) { 2435 case ICK_Identity: 2436 // Nothing to do. 2437 break; 2438 2439 case ICK_Lvalue_To_Rvalue: { 2440 assert(From->getObjectKind() != OK_ObjCProperty); 2441 FromType = FromType.getUnqualifiedType(); 2442 ExprResult FromRes = DefaultLvalueConversion(From); 2443 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2444 From = FromRes.take(); 2445 break; 2446 } 2447 2448 case ICK_Array_To_Pointer: 2449 FromType = Context.getArrayDecayedType(FromType); 2450 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2451 VK_RValue, /*BasePath=*/0, CCK).take(); 2452 break; 2453 2454 case ICK_Function_To_Pointer: 2455 FromType = Context.getPointerType(FromType); 2456 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2457 VK_RValue, /*BasePath=*/0, CCK).take(); 2458 break; 2459 2460 default: 2461 llvm_unreachable("Improper first standard conversion"); 2462 } 2463 2464 // Perform the second implicit conversion 2465 switch (SCS.Second) { 2466 case ICK_Identity: 2467 // If both sides are functions (or pointers/references to them), there could 2468 // be incompatible exception declarations. 2469 if (CheckExceptionSpecCompatibility(From, ToType)) 2470 return ExprError(); 2471 // Nothing else to do. 2472 break; 2473 2474 case ICK_NoReturn_Adjustment: 2475 // If both sides are functions (or pointers/references to them), there could 2476 // be incompatible exception declarations. 2477 if (CheckExceptionSpecCompatibility(From, ToType)) 2478 return ExprError(); 2479 2480 From = ImpCastExprToType(From, ToType, CK_NoOp, 2481 VK_RValue, /*BasePath=*/0, CCK).take(); 2482 break; 2483 2484 case ICK_Integral_Promotion: 2485 case ICK_Integral_Conversion: 2486 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2487 VK_RValue, /*BasePath=*/0, CCK).take(); 2488 break; 2489 2490 case ICK_Floating_Promotion: 2491 case ICK_Floating_Conversion: 2492 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2493 VK_RValue, /*BasePath=*/0, CCK).take(); 2494 break; 2495 2496 case ICK_Complex_Promotion: 2497 case ICK_Complex_Conversion: { 2498 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2499 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2500 CastKind CK; 2501 if (FromEl->isRealFloatingType()) { 2502 if (ToEl->isRealFloatingType()) 2503 CK = CK_FloatingComplexCast; 2504 else 2505 CK = CK_FloatingComplexToIntegralComplex; 2506 } else if (ToEl->isRealFloatingType()) { 2507 CK = CK_IntegralComplexToFloatingComplex; 2508 } else { 2509 CK = CK_IntegralComplexCast; 2510 } 2511 From = ImpCastExprToType(From, ToType, CK, 2512 VK_RValue, /*BasePath=*/0, CCK).take(); 2513 break; 2514 } 2515 2516 case ICK_Floating_Integral: 2517 if (ToType->isRealFloatingType()) 2518 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2519 VK_RValue, /*BasePath=*/0, CCK).take(); 2520 else 2521 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2522 VK_RValue, /*BasePath=*/0, CCK).take(); 2523 break; 2524 2525 case ICK_Compatible_Conversion: 2526 From = ImpCastExprToType(From, ToType, CK_NoOp, 2527 VK_RValue, /*BasePath=*/0, CCK).take(); 2528 break; 2529 2530 case ICK_Writeback_Conversion: 2531 case ICK_Pointer_Conversion: { 2532 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2533 // Diagnose incompatible Objective-C conversions 2534 if (Action == AA_Initializing || Action == AA_Assigning) 2535 Diag(From->getSourceRange().getBegin(), 2536 diag::ext_typecheck_convert_incompatible_pointer) 2537 << ToType << From->getType() << Action 2538 << From->getSourceRange() << 0; 2539 else 2540 Diag(From->getSourceRange().getBegin(), 2541 diag::ext_typecheck_convert_incompatible_pointer) 2542 << From->getType() << ToType << Action 2543 << From->getSourceRange() << 0; 2544 2545 if (From->getType()->isObjCObjectPointerType() && 2546 ToType->isObjCObjectPointerType()) 2547 EmitRelatedResultTypeNote(From); 2548 } 2549 else if (getLangOptions().ObjCAutoRefCount && 2550 !CheckObjCARCUnavailableWeakConversion(ToType, 2551 From->getType())) { 2552 if (Action == AA_Initializing) 2553 Diag(From->getSourceRange().getBegin(), 2554 diag::err_arc_weak_unavailable_assign); 2555 else 2556 Diag(From->getSourceRange().getBegin(), 2557 diag::err_arc_convesion_of_weak_unavailable) 2558 << (Action == AA_Casting) << From->getType() << ToType 2559 << From->getSourceRange(); 2560 } 2561 2562 CastKind Kind = CK_Invalid; 2563 CXXCastPath BasePath; 2564 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2565 return ExprError(); 2566 2567 // Make sure we extend blocks if necessary. 2568 // FIXME: doing this here is really ugly. 2569 if (Kind == CK_BlockPointerToObjCPointerCast) { 2570 ExprResult E = From; 2571 (void) PrepareCastToObjCObjectPointer(E); 2572 From = E.take(); 2573 } 2574 2575 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2576 .take(); 2577 break; 2578 } 2579 2580 case ICK_Pointer_Member: { 2581 CastKind Kind = CK_Invalid; 2582 CXXCastPath BasePath; 2583 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2584 return ExprError(); 2585 if (CheckExceptionSpecCompatibility(From, ToType)) 2586 return ExprError(); 2587 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2588 .take(); 2589 break; 2590 } 2591 2592 case ICK_Boolean_Conversion: 2593 // Perform half-to-boolean conversion via float. 2594 if (From->getType()->isHalfType()) { 2595 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2596 FromType = Context.FloatTy; 2597 } 2598 2599 From = ImpCastExprToType(From, Context.BoolTy, 2600 ScalarTypeToBooleanCastKind(FromType), 2601 VK_RValue, /*BasePath=*/0, CCK).take(); 2602 break; 2603 2604 case ICK_Derived_To_Base: { 2605 CXXCastPath BasePath; 2606 if (CheckDerivedToBaseConversion(From->getType(), 2607 ToType.getNonReferenceType(), 2608 From->getLocStart(), 2609 From->getSourceRange(), 2610 &BasePath, 2611 CStyle)) 2612 return ExprError(); 2613 2614 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2615 CK_DerivedToBase, From->getValueKind(), 2616 &BasePath, CCK).take(); 2617 break; 2618 } 2619 2620 case ICK_Vector_Conversion: 2621 From = ImpCastExprToType(From, ToType, CK_BitCast, 2622 VK_RValue, /*BasePath=*/0, CCK).take(); 2623 break; 2624 2625 case ICK_Vector_Splat: 2626 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2627 VK_RValue, /*BasePath=*/0, CCK).take(); 2628 break; 2629 2630 case ICK_Complex_Real: 2631 // Case 1. x -> _Complex y 2632 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2633 QualType ElType = ToComplex->getElementType(); 2634 bool isFloatingComplex = ElType->isRealFloatingType(); 2635 2636 // x -> y 2637 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2638 // do nothing 2639 } else if (From->getType()->isRealFloatingType()) { 2640 From = ImpCastExprToType(From, ElType, 2641 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2642 } else { 2643 assert(From->getType()->isIntegerType()); 2644 From = ImpCastExprToType(From, ElType, 2645 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2646 } 2647 // y -> _Complex y 2648 From = ImpCastExprToType(From, ToType, 2649 isFloatingComplex ? CK_FloatingRealToComplex 2650 : CK_IntegralRealToComplex).take(); 2651 2652 // Case 2. _Complex x -> y 2653 } else { 2654 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2655 assert(FromComplex); 2656 2657 QualType ElType = FromComplex->getElementType(); 2658 bool isFloatingComplex = ElType->isRealFloatingType(); 2659 2660 // _Complex x -> x 2661 From = ImpCastExprToType(From, ElType, 2662 isFloatingComplex ? CK_FloatingComplexToReal 2663 : CK_IntegralComplexToReal, 2664 VK_RValue, /*BasePath=*/0, CCK).take(); 2665 2666 // x -> y 2667 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2668 // do nothing 2669 } else if (ToType->isRealFloatingType()) { 2670 From = ImpCastExprToType(From, ToType, 2671 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2672 VK_RValue, /*BasePath=*/0, CCK).take(); 2673 } else { 2674 assert(ToType->isIntegerType()); 2675 From = ImpCastExprToType(From, ToType, 2676 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2677 VK_RValue, /*BasePath=*/0, CCK).take(); 2678 } 2679 } 2680 break; 2681 2682 case ICK_Block_Pointer_Conversion: { 2683 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2684 VK_RValue, /*BasePath=*/0, CCK).take(); 2685 break; 2686 } 2687 2688 case ICK_TransparentUnionConversion: { 2689 ExprResult FromRes = Owned(From); 2690 Sema::AssignConvertType ConvTy = 2691 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2692 if (FromRes.isInvalid()) 2693 return ExprError(); 2694 From = FromRes.take(); 2695 assert ((ConvTy == Sema::Compatible) && 2696 "Improper transparent union conversion"); 2697 (void)ConvTy; 2698 break; 2699 } 2700 2701 case ICK_Lvalue_To_Rvalue: 2702 case ICK_Array_To_Pointer: 2703 case ICK_Function_To_Pointer: 2704 case ICK_Qualification: 2705 case ICK_Num_Conversion_Kinds: 2706 llvm_unreachable("Improper second standard conversion"); 2707 } 2708 2709 switch (SCS.Third) { 2710 case ICK_Identity: 2711 // Nothing to do. 2712 break; 2713 2714 case ICK_Qualification: { 2715 // The qualification keeps the category of the inner expression, unless the 2716 // target type isn't a reference. 2717 ExprValueKind VK = ToType->isReferenceType() ? 2718 From->getValueKind() : VK_RValue; 2719 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2720 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2721 2722 if (SCS.DeprecatedStringLiteralToCharPtr && 2723 !getLangOptions().WritableStrings) 2724 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2725 << ToType.getNonReferenceType(); 2726 2727 break; 2728 } 2729 2730 default: 2731 llvm_unreachable("Improper third standard conversion"); 2732 } 2733 2734 return Owned(From); 2735} 2736 2737ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2738 SourceLocation KWLoc, 2739 ParsedType Ty, 2740 SourceLocation RParen) { 2741 TypeSourceInfo *TSInfo; 2742 QualType T = GetTypeFromParser(Ty, &TSInfo); 2743 2744 if (!TSInfo) 2745 TSInfo = Context.getTrivialTypeSourceInfo(T); 2746 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2747} 2748 2749/// \brief Check the completeness of a type in a unary type trait. 2750/// 2751/// If the particular type trait requires a complete type, tries to complete 2752/// it. If completing the type fails, a diagnostic is emitted and false 2753/// returned. If completing the type succeeds or no completion was required, 2754/// returns true. 2755static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2756 UnaryTypeTrait UTT, 2757 SourceLocation Loc, 2758 QualType ArgTy) { 2759 // C++0x [meta.unary.prop]p3: 2760 // For all of the class templates X declared in this Clause, instantiating 2761 // that template with a template argument that is a class template 2762 // specialization may result in the implicit instantiation of the template 2763 // argument if and only if the semantics of X require that the argument 2764 // must be a complete type. 2765 // We apply this rule to all the type trait expressions used to implement 2766 // these class templates. We also try to follow any GCC documented behavior 2767 // in these expressions to ensure portability of standard libraries. 2768 switch (UTT) { 2769 // is_complete_type somewhat obviously cannot require a complete type. 2770 case UTT_IsCompleteType: 2771 // Fall-through 2772 2773 // These traits are modeled on the type predicates in C++0x 2774 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2775 // requiring a complete type, as whether or not they return true cannot be 2776 // impacted by the completeness of the type. 2777 case UTT_IsVoid: 2778 case UTT_IsIntegral: 2779 case UTT_IsFloatingPoint: 2780 case UTT_IsArray: 2781 case UTT_IsPointer: 2782 case UTT_IsLvalueReference: 2783 case UTT_IsRvalueReference: 2784 case UTT_IsMemberFunctionPointer: 2785 case UTT_IsMemberObjectPointer: 2786 case UTT_IsEnum: 2787 case UTT_IsUnion: 2788 case UTT_IsClass: 2789 case UTT_IsFunction: 2790 case UTT_IsReference: 2791 case UTT_IsArithmetic: 2792 case UTT_IsFundamental: 2793 case UTT_IsObject: 2794 case UTT_IsScalar: 2795 case UTT_IsCompound: 2796 case UTT_IsMemberPointer: 2797 // Fall-through 2798 2799 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2800 // which requires some of its traits to have the complete type. However, 2801 // the completeness of the type cannot impact these traits' semantics, and 2802 // so they don't require it. This matches the comments on these traits in 2803 // Table 49. 2804 case UTT_IsConst: 2805 case UTT_IsVolatile: 2806 case UTT_IsSigned: 2807 case UTT_IsUnsigned: 2808 return true; 2809 2810 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2811 // applied to a complete type. 2812 case UTT_IsTrivial: 2813 case UTT_IsTriviallyCopyable: 2814 case UTT_IsStandardLayout: 2815 case UTT_IsPOD: 2816 case UTT_IsLiteral: 2817 case UTT_IsEmpty: 2818 case UTT_IsPolymorphic: 2819 case UTT_IsAbstract: 2820 // Fall-through 2821 2822 // These traits require a complete type. 2823 case UTT_IsFinal: 2824 2825 // These trait expressions are designed to help implement predicates in 2826 // [meta.unary.prop] despite not being named the same. They are specified 2827 // by both GCC and the Embarcadero C++ compiler, and require the complete 2828 // type due to the overarching C++0x type predicates being implemented 2829 // requiring the complete type. 2830 case UTT_HasNothrowAssign: 2831 case UTT_HasNothrowConstructor: 2832 case UTT_HasNothrowCopy: 2833 case UTT_HasTrivialAssign: 2834 case UTT_HasTrivialDefaultConstructor: 2835 case UTT_HasTrivialCopy: 2836 case UTT_HasTrivialDestructor: 2837 case UTT_HasVirtualDestructor: 2838 // Arrays of unknown bound are expressly allowed. 2839 QualType ElTy = ArgTy; 2840 if (ArgTy->isIncompleteArrayType()) 2841 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 2842 2843 // The void type is expressly allowed. 2844 if (ElTy->isVoidType()) 2845 return true; 2846 2847 return !S.RequireCompleteType( 2848 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 2849 } 2850 llvm_unreachable("Type trait not handled by switch"); 2851} 2852 2853static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 2854 SourceLocation KeyLoc, QualType T) { 2855 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 2856 2857 ASTContext &C = Self.Context; 2858 switch(UTT) { 2859 // Type trait expressions corresponding to the primary type category 2860 // predicates in C++0x [meta.unary.cat]. 2861 case UTT_IsVoid: 2862 return T->isVoidType(); 2863 case UTT_IsIntegral: 2864 return T->isIntegralType(C); 2865 case UTT_IsFloatingPoint: 2866 return T->isFloatingType(); 2867 case UTT_IsArray: 2868 return T->isArrayType(); 2869 case UTT_IsPointer: 2870 return T->isPointerType(); 2871 case UTT_IsLvalueReference: 2872 return T->isLValueReferenceType(); 2873 case UTT_IsRvalueReference: 2874 return T->isRValueReferenceType(); 2875 case UTT_IsMemberFunctionPointer: 2876 return T->isMemberFunctionPointerType(); 2877 case UTT_IsMemberObjectPointer: 2878 return T->isMemberDataPointerType(); 2879 case UTT_IsEnum: 2880 return T->isEnumeralType(); 2881 case UTT_IsUnion: 2882 return T->isUnionType(); 2883 case UTT_IsClass: 2884 return T->isClassType() || T->isStructureType(); 2885 case UTT_IsFunction: 2886 return T->isFunctionType(); 2887 2888 // Type trait expressions which correspond to the convenient composition 2889 // predicates in C++0x [meta.unary.comp]. 2890 case UTT_IsReference: 2891 return T->isReferenceType(); 2892 case UTT_IsArithmetic: 2893 return T->isArithmeticType() && !T->isEnumeralType(); 2894 case UTT_IsFundamental: 2895 return T->isFundamentalType(); 2896 case UTT_IsObject: 2897 return T->isObjectType(); 2898 case UTT_IsScalar: 2899 // Note: semantic analysis depends on Objective-C lifetime types to be 2900 // considered scalar types. However, such types do not actually behave 2901 // like scalar types at run time (since they may require retain/release 2902 // operations), so we report them as non-scalar. 2903 if (T->isObjCLifetimeType()) { 2904 switch (T.getObjCLifetime()) { 2905 case Qualifiers::OCL_None: 2906 case Qualifiers::OCL_ExplicitNone: 2907 return true; 2908 2909 case Qualifiers::OCL_Strong: 2910 case Qualifiers::OCL_Weak: 2911 case Qualifiers::OCL_Autoreleasing: 2912 return false; 2913 } 2914 } 2915 2916 return T->isScalarType(); 2917 case UTT_IsCompound: 2918 return T->isCompoundType(); 2919 case UTT_IsMemberPointer: 2920 return T->isMemberPointerType(); 2921 2922 // Type trait expressions which correspond to the type property predicates 2923 // in C++0x [meta.unary.prop]. 2924 case UTT_IsConst: 2925 return T.isConstQualified(); 2926 case UTT_IsVolatile: 2927 return T.isVolatileQualified(); 2928 case UTT_IsTrivial: 2929 return T.isTrivialType(Self.Context); 2930 case UTT_IsTriviallyCopyable: 2931 return T.isTriviallyCopyableType(Self.Context); 2932 case UTT_IsStandardLayout: 2933 return T->isStandardLayoutType(); 2934 case UTT_IsPOD: 2935 return T.isPODType(Self.Context); 2936 case UTT_IsLiteral: 2937 return T->isLiteralType(); 2938 case UTT_IsEmpty: 2939 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2940 return !RD->isUnion() && RD->isEmpty(); 2941 return false; 2942 case UTT_IsPolymorphic: 2943 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2944 return RD->isPolymorphic(); 2945 return false; 2946 case UTT_IsAbstract: 2947 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2948 return RD->isAbstract(); 2949 return false; 2950 case UTT_IsFinal: 2951 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2952 return RD->hasAttr<FinalAttr>(); 2953 return false; 2954 case UTT_IsSigned: 2955 return T->isSignedIntegerType(); 2956 case UTT_IsUnsigned: 2957 return T->isUnsignedIntegerType(); 2958 2959 // Type trait expressions which query classes regarding their construction, 2960 // destruction, and copying. Rather than being based directly on the 2961 // related type predicates in the standard, they are specified by both 2962 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 2963 // specifications. 2964 // 2965 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 2966 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 2967 case UTT_HasTrivialDefaultConstructor: 2968 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 2969 // If __is_pod (type) is true then the trait is true, else if type is 2970 // a cv class or union type (or array thereof) with a trivial default 2971 // constructor ([class.ctor]) then the trait is true, else it is false. 2972 if (T.isPODType(Self.Context)) 2973 return true; 2974 if (const RecordType *RT = 2975 C.getBaseElementType(T)->getAs<RecordType>()) 2976 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDefaultConstructor(); 2977 return false; 2978 case UTT_HasTrivialCopy: 2979 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 2980 // If __is_pod (type) is true or type is a reference type then 2981 // the trait is true, else if type is a cv class or union type 2982 // with a trivial copy constructor ([class.copy]) then the trait 2983 // is true, else it is false. 2984 if (T.isPODType(Self.Context) || T->isReferenceType()) 2985 return true; 2986 if (const RecordType *RT = T->getAs<RecordType>()) 2987 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyConstructor(); 2988 return false; 2989 case UTT_HasTrivialAssign: 2990 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 2991 // If type is const qualified or is a reference type then the 2992 // trait is false. Otherwise if __is_pod (type) is true then the 2993 // trait is true, else if type is a cv class or union type with 2994 // a trivial copy assignment ([class.copy]) then the trait is 2995 // true, else it is false. 2996 // Note: the const and reference restrictions are interesting, 2997 // given that const and reference members don't prevent a class 2998 // from having a trivial copy assignment operator (but do cause 2999 // errors if the copy assignment operator is actually used, q.v. 3000 // [class.copy]p12). 3001 3002 if (C.getBaseElementType(T).isConstQualified()) 3003 return false; 3004 if (T.isPODType(Self.Context)) 3005 return true; 3006 if (const RecordType *RT = T->getAs<RecordType>()) 3007 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyAssignment(); 3008 return false; 3009 case UTT_HasTrivialDestructor: 3010 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3011 // If __is_pod (type) is true or type is a reference type 3012 // then the trait is true, else if type is a cv class or union 3013 // type (or array thereof) with a trivial destructor 3014 // ([class.dtor]) then the trait is true, else it is 3015 // false. 3016 if (T.isPODType(Self.Context) || T->isReferenceType()) 3017 return true; 3018 3019 // Objective-C++ ARC: autorelease types don't require destruction. 3020 if (T->isObjCLifetimeType() && 3021 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3022 return true; 3023 3024 if (const RecordType *RT = 3025 C.getBaseElementType(T)->getAs<RecordType>()) 3026 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDestructor(); 3027 return false; 3028 // TODO: Propagate nothrowness for implicitly declared special members. 3029 case UTT_HasNothrowAssign: 3030 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3031 // If type is const qualified or is a reference type then the 3032 // trait is false. Otherwise if __has_trivial_assign (type) 3033 // is true then the trait is true, else if type is a cv class 3034 // or union type with copy assignment operators that are known 3035 // not to throw an exception then the trait is true, else it is 3036 // false. 3037 if (C.getBaseElementType(T).isConstQualified()) 3038 return false; 3039 if (T->isReferenceType()) 3040 return false; 3041 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3042 return true; 3043 if (const RecordType *RT = T->getAs<RecordType>()) { 3044 CXXRecordDecl* RD = cast<CXXRecordDecl>(RT->getDecl()); 3045 if (RD->hasTrivialCopyAssignment()) 3046 return true; 3047 3048 bool FoundAssign = false; 3049 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(OO_Equal); 3050 LookupResult Res(Self, DeclarationNameInfo(Name, KeyLoc), 3051 Sema::LookupOrdinaryName); 3052 if (Self.LookupQualifiedName(Res, RD)) { 3053 Res.suppressDiagnostics(); 3054 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3055 Op != OpEnd; ++Op) { 3056 if (isa<FunctionTemplateDecl>(*Op)) 3057 continue; 3058 3059 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3060 if (Operator->isCopyAssignmentOperator()) { 3061 FoundAssign = true; 3062 const FunctionProtoType *CPT 3063 = Operator->getType()->getAs<FunctionProtoType>(); 3064 if (CPT->getExceptionSpecType() == EST_Delayed) 3065 return false; 3066 if (!CPT->isNothrow(Self.Context)) 3067 return false; 3068 } 3069 } 3070 } 3071 3072 return FoundAssign; 3073 } 3074 return false; 3075 case UTT_HasNothrowCopy: 3076 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3077 // If __has_trivial_copy (type) is true then the trait is true, else 3078 // if type is a cv class or union type with copy constructors that are 3079 // known not to throw an exception then the trait is true, else it is 3080 // false. 3081 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3082 return true; 3083 if (const RecordType *RT = T->getAs<RecordType>()) { 3084 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3085 if (RD->hasTrivialCopyConstructor()) 3086 return true; 3087 3088 bool FoundConstructor = false; 3089 unsigned FoundTQs; 3090 DeclContext::lookup_const_iterator Con, ConEnd; 3091 for (llvm::tie(Con, ConEnd) = Self.LookupConstructors(RD); 3092 Con != ConEnd; ++Con) { 3093 // A template constructor is never a copy constructor. 3094 // FIXME: However, it may actually be selected at the actual overload 3095 // resolution point. 3096 if (isa<FunctionTemplateDecl>(*Con)) 3097 continue; 3098 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3099 if (Constructor->isCopyConstructor(FoundTQs)) { 3100 FoundConstructor = true; 3101 const FunctionProtoType *CPT 3102 = Constructor->getType()->getAs<FunctionProtoType>(); 3103 if (CPT->getExceptionSpecType() == EST_Delayed) 3104 return false; 3105 // FIXME: check whether evaluating default arguments can throw. 3106 // For now, we'll be conservative and assume that they can throw. 3107 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3108 return false; 3109 } 3110 } 3111 3112 return FoundConstructor; 3113 } 3114 return false; 3115 case UTT_HasNothrowConstructor: 3116 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3117 // If __has_trivial_constructor (type) is true then the trait is 3118 // true, else if type is a cv class or union type (or array 3119 // thereof) with a default constructor that is known not to 3120 // throw an exception then the trait is true, else it is false. 3121 if (T.isPODType(C) || T->isObjCLifetimeType()) 3122 return true; 3123 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) { 3124 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3125 if (RD->hasTrivialDefaultConstructor()) 3126 return true; 3127 3128 DeclContext::lookup_const_iterator Con, ConEnd; 3129 for (llvm::tie(Con, ConEnd) = Self.LookupConstructors(RD); 3130 Con != ConEnd; ++Con) { 3131 // FIXME: In C++0x, a constructor template can be a default constructor. 3132 if (isa<FunctionTemplateDecl>(*Con)) 3133 continue; 3134 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3135 if (Constructor->isDefaultConstructor()) { 3136 const FunctionProtoType *CPT 3137 = Constructor->getType()->getAs<FunctionProtoType>(); 3138 if (CPT->getExceptionSpecType() == EST_Delayed) 3139 return false; 3140 // TODO: check whether evaluating default arguments can throw. 3141 // For now, we'll be conservative and assume that they can throw. 3142 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3143 } 3144 } 3145 } 3146 return false; 3147 case UTT_HasVirtualDestructor: 3148 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3149 // If type is a class type with a virtual destructor ([class.dtor]) 3150 // then the trait is true, else it is false. 3151 if (const RecordType *Record = T->getAs<RecordType>()) { 3152 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 3153 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3154 return Destructor->isVirtual(); 3155 } 3156 return false; 3157 3158 // These type trait expressions are modeled on the specifications for the 3159 // Embarcadero C++0x type trait functions: 3160 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3161 case UTT_IsCompleteType: 3162 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3163 // Returns True if and only if T is a complete type at the point of the 3164 // function call. 3165 return !T->isIncompleteType(); 3166 } 3167 llvm_unreachable("Type trait not covered by switch"); 3168} 3169 3170ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3171 SourceLocation KWLoc, 3172 TypeSourceInfo *TSInfo, 3173 SourceLocation RParen) { 3174 QualType T = TSInfo->getType(); 3175 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3176 return ExprError(); 3177 3178 bool Value = false; 3179 if (!T->isDependentType()) 3180 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3181 3182 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3183 RParen, Context.BoolTy)); 3184} 3185 3186ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3187 SourceLocation KWLoc, 3188 ParsedType LhsTy, 3189 ParsedType RhsTy, 3190 SourceLocation RParen) { 3191 TypeSourceInfo *LhsTSInfo; 3192 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3193 if (!LhsTSInfo) 3194 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3195 3196 TypeSourceInfo *RhsTSInfo; 3197 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3198 if (!RhsTSInfo) 3199 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3200 3201 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3202} 3203 3204static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3205 QualType LhsT, QualType RhsT, 3206 SourceLocation KeyLoc) { 3207 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3208 "Cannot evaluate traits of dependent types"); 3209 3210 switch(BTT) { 3211 case BTT_IsBaseOf: { 3212 // C++0x [meta.rel]p2 3213 // Base is a base class of Derived without regard to cv-qualifiers or 3214 // Base and Derived are not unions and name the same class type without 3215 // regard to cv-qualifiers. 3216 3217 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3218 if (!lhsRecord) return false; 3219 3220 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3221 if (!rhsRecord) return false; 3222 3223 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3224 == (lhsRecord == rhsRecord)); 3225 3226 if (lhsRecord == rhsRecord) 3227 return !lhsRecord->getDecl()->isUnion(); 3228 3229 // C++0x [meta.rel]p2: 3230 // If Base and Derived are class types and are different types 3231 // (ignoring possible cv-qualifiers) then Derived shall be a 3232 // complete type. 3233 if (Self.RequireCompleteType(KeyLoc, RhsT, 3234 diag::err_incomplete_type_used_in_type_trait_expr)) 3235 return false; 3236 3237 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3238 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3239 } 3240 case BTT_IsSame: 3241 return Self.Context.hasSameType(LhsT, RhsT); 3242 case BTT_TypeCompatible: 3243 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3244 RhsT.getUnqualifiedType()); 3245 case BTT_IsConvertible: 3246 case BTT_IsConvertibleTo: { 3247 // C++0x [meta.rel]p4: 3248 // Given the following function prototype: 3249 // 3250 // template <class T> 3251 // typename add_rvalue_reference<T>::type create(); 3252 // 3253 // the predicate condition for a template specialization 3254 // is_convertible<From, To> shall be satisfied if and only if 3255 // the return expression in the following code would be 3256 // well-formed, including any implicit conversions to the return 3257 // type of the function: 3258 // 3259 // To test() { 3260 // return create<From>(); 3261 // } 3262 // 3263 // Access checking is performed as if in a context unrelated to To and 3264 // From. Only the validity of the immediate context of the expression 3265 // of the return-statement (including conversions to the return type) 3266 // is considered. 3267 // 3268 // We model the initialization as a copy-initialization of a temporary 3269 // of the appropriate type, which for this expression is identical to the 3270 // return statement (since NRVO doesn't apply). 3271 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3272 LhsT = Self.Context.getRValueReferenceType(LhsT); 3273 3274 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3275 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3276 Expr::getValueKindForType(LhsT)); 3277 Expr *FromPtr = &From; 3278 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3279 SourceLocation())); 3280 3281 // Perform the initialization in an unevaluated context within a SFINAE 3282 // trap at translation unit scope. 3283 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3284 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3285 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3286 InitializationSequence Init(Self, To, Kind, &FromPtr, 1); 3287 if (Init.Failed()) 3288 return false; 3289 3290 ExprResult Result = Init.Perform(Self, To, Kind, MultiExprArg(&FromPtr, 1)); 3291 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3292 } 3293 } 3294 llvm_unreachable("Unknown type trait or not implemented"); 3295} 3296 3297ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3298 SourceLocation KWLoc, 3299 TypeSourceInfo *LhsTSInfo, 3300 TypeSourceInfo *RhsTSInfo, 3301 SourceLocation RParen) { 3302 QualType LhsT = LhsTSInfo->getType(); 3303 QualType RhsT = RhsTSInfo->getType(); 3304 3305 if (BTT == BTT_TypeCompatible) { 3306 if (getLangOptions().CPlusPlus) { 3307 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3308 << SourceRange(KWLoc, RParen); 3309 return ExprError(); 3310 } 3311 } 3312 3313 bool Value = false; 3314 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3315 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3316 3317 // Select trait result type. 3318 QualType ResultType; 3319 switch (BTT) { 3320 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3321 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3322 case BTT_IsSame: ResultType = Context.BoolTy; break; 3323 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3324 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3325 } 3326 3327 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3328 RhsTSInfo, Value, RParen, 3329 ResultType)); 3330} 3331 3332ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3333 SourceLocation KWLoc, 3334 ParsedType Ty, 3335 Expr* DimExpr, 3336 SourceLocation RParen) { 3337 TypeSourceInfo *TSInfo; 3338 QualType T = GetTypeFromParser(Ty, &TSInfo); 3339 if (!TSInfo) 3340 TSInfo = Context.getTrivialTypeSourceInfo(T); 3341 3342 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3343} 3344 3345static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3346 QualType T, Expr *DimExpr, 3347 SourceLocation KeyLoc) { 3348 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3349 3350 switch(ATT) { 3351 case ATT_ArrayRank: 3352 if (T->isArrayType()) { 3353 unsigned Dim = 0; 3354 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3355 ++Dim; 3356 T = AT->getElementType(); 3357 } 3358 return Dim; 3359 } 3360 return 0; 3361 3362 case ATT_ArrayExtent: { 3363 llvm::APSInt Value; 3364 uint64_t Dim; 3365 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3366 Self.PDiag(diag::err_dimension_expr_not_constant_integer), 3367 false).isInvalid()) 3368 return 0; 3369 if (Value.isSigned() && Value.isNegative()) { 3370 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer), 3371 DimExpr->getSourceRange(); 3372 return 0; 3373 } 3374 Dim = Value.getLimitedValue(); 3375 3376 if (T->isArrayType()) { 3377 unsigned D = 0; 3378 bool Matched = false; 3379 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3380 if (Dim == D) { 3381 Matched = true; 3382 break; 3383 } 3384 ++D; 3385 T = AT->getElementType(); 3386 } 3387 3388 if (Matched && T->isArrayType()) { 3389 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3390 return CAT->getSize().getLimitedValue(); 3391 } 3392 } 3393 return 0; 3394 } 3395 } 3396 llvm_unreachable("Unknown type trait or not implemented"); 3397} 3398 3399ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3400 SourceLocation KWLoc, 3401 TypeSourceInfo *TSInfo, 3402 Expr* DimExpr, 3403 SourceLocation RParen) { 3404 QualType T = TSInfo->getType(); 3405 3406 // FIXME: This should likely be tracked as an APInt to remove any host 3407 // assumptions about the width of size_t on the target. 3408 uint64_t Value = 0; 3409 if (!T->isDependentType()) 3410 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3411 3412 // While the specification for these traits from the Embarcadero C++ 3413 // compiler's documentation says the return type is 'unsigned int', Clang 3414 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3415 // compiler, there is no difference. On several other platforms this is an 3416 // important distinction. 3417 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3418 DimExpr, RParen, 3419 Context.getSizeType())); 3420} 3421 3422ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3423 SourceLocation KWLoc, 3424 Expr *Queried, 3425 SourceLocation RParen) { 3426 // If error parsing the expression, ignore. 3427 if (!Queried) 3428 return ExprError(); 3429 3430 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3431 3432 return move(Result); 3433} 3434 3435static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3436 switch (ET) { 3437 case ET_IsLValueExpr: return E->isLValue(); 3438 case ET_IsRValueExpr: return E->isRValue(); 3439 } 3440 llvm_unreachable("Expression trait not covered by switch"); 3441} 3442 3443ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3444 SourceLocation KWLoc, 3445 Expr *Queried, 3446 SourceLocation RParen) { 3447 if (Queried->isTypeDependent()) { 3448 // Delay type-checking for type-dependent expressions. 3449 } else if (Queried->getType()->isPlaceholderType()) { 3450 ExprResult PE = CheckPlaceholderExpr(Queried); 3451 if (PE.isInvalid()) return ExprError(); 3452 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3453 } 3454 3455 bool Value = EvaluateExpressionTrait(ET, Queried); 3456 3457 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3458 RParen, Context.BoolTy)); 3459} 3460 3461QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3462 ExprValueKind &VK, 3463 SourceLocation Loc, 3464 bool isIndirect) { 3465 assert(!LHS.get()->getType()->isPlaceholderType() && 3466 !RHS.get()->getType()->isPlaceholderType() && 3467 "placeholders should have been weeded out by now"); 3468 3469 // The LHS undergoes lvalue conversions if this is ->*. 3470 if (isIndirect) { 3471 LHS = DefaultLvalueConversion(LHS.take()); 3472 if (LHS.isInvalid()) return QualType(); 3473 } 3474 3475 // The RHS always undergoes lvalue conversions. 3476 RHS = DefaultLvalueConversion(RHS.take()); 3477 if (RHS.isInvalid()) return QualType(); 3478 3479 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3480 // C++ 5.5p2 3481 // The binary operator .* [p3: ->*] binds its second operand, which shall 3482 // be of type "pointer to member of T" (where T is a completely-defined 3483 // class type) [...] 3484 QualType RHSType = RHS.get()->getType(); 3485 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3486 if (!MemPtr) { 3487 Diag(Loc, diag::err_bad_memptr_rhs) 3488 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3489 return QualType(); 3490 } 3491 3492 QualType Class(MemPtr->getClass(), 0); 3493 3494 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3495 // member pointer points must be completely-defined. However, there is no 3496 // reason for this semantic distinction, and the rule is not enforced by 3497 // other compilers. Therefore, we do not check this property, as it is 3498 // likely to be considered a defect. 3499 3500 // C++ 5.5p2 3501 // [...] to its first operand, which shall be of class T or of a class of 3502 // which T is an unambiguous and accessible base class. [p3: a pointer to 3503 // such a class] 3504 QualType LHSType = LHS.get()->getType(); 3505 if (isIndirect) { 3506 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3507 LHSType = Ptr->getPointeeType(); 3508 else { 3509 Diag(Loc, diag::err_bad_memptr_lhs) 3510 << OpSpelling << 1 << LHSType 3511 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3512 return QualType(); 3513 } 3514 } 3515 3516 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3517 // If we want to check the hierarchy, we need a complete type. 3518 if (RequireCompleteType(Loc, LHSType, PDiag(diag::err_bad_memptr_lhs) 3519 << OpSpelling << (int)isIndirect)) { 3520 return QualType(); 3521 } 3522 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3523 /*DetectVirtual=*/false); 3524 // FIXME: Would it be useful to print full ambiguity paths, or is that 3525 // overkill? 3526 if (!IsDerivedFrom(LHSType, Class, Paths) || 3527 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3528 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3529 << (int)isIndirect << LHS.get()->getType(); 3530 return QualType(); 3531 } 3532 // Cast LHS to type of use. 3533 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3534 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3535 3536 CXXCastPath BasePath; 3537 BuildBasePathArray(Paths, BasePath); 3538 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3539 &BasePath); 3540 } 3541 3542 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3543 // Diagnose use of pointer-to-member type which when used as 3544 // the functional cast in a pointer-to-member expression. 3545 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3546 return QualType(); 3547 } 3548 3549 // C++ 5.5p2 3550 // The result is an object or a function of the type specified by the 3551 // second operand. 3552 // The cv qualifiers are the union of those in the pointer and the left side, 3553 // in accordance with 5.5p5 and 5.2.5. 3554 QualType Result = MemPtr->getPointeeType(); 3555 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3556 3557 // C++0x [expr.mptr.oper]p6: 3558 // In a .* expression whose object expression is an rvalue, the program is 3559 // ill-formed if the second operand is a pointer to member function with 3560 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3561 // expression is an lvalue, the program is ill-formed if the second operand 3562 // is a pointer to member function with ref-qualifier &&. 3563 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3564 switch (Proto->getRefQualifier()) { 3565 case RQ_None: 3566 // Do nothing 3567 break; 3568 3569 case RQ_LValue: 3570 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3571 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3572 << RHSType << 1 << LHS.get()->getSourceRange(); 3573 break; 3574 3575 case RQ_RValue: 3576 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 3577 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3578 << RHSType << 0 << LHS.get()->getSourceRange(); 3579 break; 3580 } 3581 } 3582 3583 // C++ [expr.mptr.oper]p6: 3584 // The result of a .* expression whose second operand is a pointer 3585 // to a data member is of the same value category as its 3586 // first operand. The result of a .* expression whose second 3587 // operand is a pointer to a member function is a prvalue. The 3588 // result of an ->* expression is an lvalue if its second operand 3589 // is a pointer to data member and a prvalue otherwise. 3590 if (Result->isFunctionType()) { 3591 VK = VK_RValue; 3592 return Context.BoundMemberTy; 3593 } else if (isIndirect) { 3594 VK = VK_LValue; 3595 } else { 3596 VK = LHS.get()->getValueKind(); 3597 } 3598 3599 return Result; 3600} 3601 3602/// \brief Try to convert a type to another according to C++0x 5.16p3. 3603/// 3604/// This is part of the parameter validation for the ? operator. If either 3605/// value operand is a class type, the two operands are attempted to be 3606/// converted to each other. This function does the conversion in one direction. 3607/// It returns true if the program is ill-formed and has already been diagnosed 3608/// as such. 3609static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 3610 SourceLocation QuestionLoc, 3611 bool &HaveConversion, 3612 QualType &ToType) { 3613 HaveConversion = false; 3614 ToType = To->getType(); 3615 3616 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 3617 SourceLocation()); 3618 // C++0x 5.16p3 3619 // The process for determining whether an operand expression E1 of type T1 3620 // can be converted to match an operand expression E2 of type T2 is defined 3621 // as follows: 3622 // -- If E2 is an lvalue: 3623 bool ToIsLvalue = To->isLValue(); 3624 if (ToIsLvalue) { 3625 // E1 can be converted to match E2 if E1 can be implicitly converted to 3626 // type "lvalue reference to T2", subject to the constraint that in the 3627 // conversion the reference must bind directly to E1. 3628 QualType T = Self.Context.getLValueReferenceType(ToType); 3629 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3630 3631 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3632 if (InitSeq.isDirectReferenceBinding()) { 3633 ToType = T; 3634 HaveConversion = true; 3635 return false; 3636 } 3637 3638 if (InitSeq.isAmbiguous()) 3639 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3640 } 3641 3642 // -- If E2 is an rvalue, or if the conversion above cannot be done: 3643 // -- if E1 and E2 have class type, and the underlying class types are 3644 // the same or one is a base class of the other: 3645 QualType FTy = From->getType(); 3646 QualType TTy = To->getType(); 3647 const RecordType *FRec = FTy->getAs<RecordType>(); 3648 const RecordType *TRec = TTy->getAs<RecordType>(); 3649 bool FDerivedFromT = FRec && TRec && FRec != TRec && 3650 Self.IsDerivedFrom(FTy, TTy); 3651 if (FRec && TRec && 3652 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 3653 // E1 can be converted to match E2 if the class of T2 is the 3654 // same type as, or a base class of, the class of T1, and 3655 // [cv2 > cv1]. 3656 if (FRec == TRec || FDerivedFromT) { 3657 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 3658 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3659 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3660 if (InitSeq) { 3661 HaveConversion = true; 3662 return false; 3663 } 3664 3665 if (InitSeq.isAmbiguous()) 3666 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3667 } 3668 } 3669 3670 return false; 3671 } 3672 3673 // -- Otherwise: E1 can be converted to match E2 if E1 can be 3674 // implicitly converted to the type that expression E2 would have 3675 // if E2 were converted to an rvalue (or the type it has, if E2 is 3676 // an rvalue). 3677 // 3678 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 3679 // to the array-to-pointer or function-to-pointer conversions. 3680 if (!TTy->getAs<TagType>()) 3681 TTy = TTy.getUnqualifiedType(); 3682 3683 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3684 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3685 HaveConversion = !InitSeq.Failed(); 3686 ToType = TTy; 3687 if (InitSeq.isAmbiguous()) 3688 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3689 3690 return false; 3691} 3692 3693/// \brief Try to find a common type for two according to C++0x 5.16p5. 3694/// 3695/// This is part of the parameter validation for the ? operator. If either 3696/// value operand is a class type, overload resolution is used to find a 3697/// conversion to a common type. 3698static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 3699 SourceLocation QuestionLoc) { 3700 Expr *Args[2] = { LHS.get(), RHS.get() }; 3701 OverloadCandidateSet CandidateSet(QuestionLoc); 3702 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 2, 3703 CandidateSet); 3704 3705 OverloadCandidateSet::iterator Best; 3706 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 3707 case OR_Success: { 3708 // We found a match. Perform the conversions on the arguments and move on. 3709 ExprResult LHSRes = 3710 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 3711 Best->Conversions[0], Sema::AA_Converting); 3712 if (LHSRes.isInvalid()) 3713 break; 3714 LHS = move(LHSRes); 3715 3716 ExprResult RHSRes = 3717 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 3718 Best->Conversions[1], Sema::AA_Converting); 3719 if (RHSRes.isInvalid()) 3720 break; 3721 RHS = move(RHSRes); 3722 if (Best->Function) 3723 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 3724 return false; 3725 } 3726 3727 case OR_No_Viable_Function: 3728 3729 // Emit a better diagnostic if one of the expressions is a null pointer 3730 // constant and the other is a pointer type. In this case, the user most 3731 // likely forgot to take the address of the other expression. 3732 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 3733 return true; 3734 3735 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3736 << LHS.get()->getType() << RHS.get()->getType() 3737 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3738 return true; 3739 3740 case OR_Ambiguous: 3741 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 3742 << LHS.get()->getType() << RHS.get()->getType() 3743 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3744 // FIXME: Print the possible common types by printing the return types of 3745 // the viable candidates. 3746 break; 3747 3748 case OR_Deleted: 3749 llvm_unreachable("Conditional operator has only built-in overloads"); 3750 } 3751 return true; 3752} 3753 3754/// \brief Perform an "extended" implicit conversion as returned by 3755/// TryClassUnification. 3756static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 3757 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3758 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 3759 SourceLocation()); 3760 Expr *Arg = E.take(); 3761 InitializationSequence InitSeq(Self, Entity, Kind, &Arg, 1); 3762 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, MultiExprArg(&Arg, 1)); 3763 if (Result.isInvalid()) 3764 return true; 3765 3766 E = Result; 3767 return false; 3768} 3769 3770/// \brief Check the operands of ?: under C++ semantics. 3771/// 3772/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 3773/// extension. In this case, LHS == Cond. (But they're not aliases.) 3774QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, ExprResult &RHS, 3775 ExprValueKind &VK, ExprObjectKind &OK, 3776 SourceLocation QuestionLoc) { 3777 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 3778 // interface pointers. 3779 3780 // C++0x 5.16p1 3781 // The first expression is contextually converted to bool. 3782 if (!Cond.get()->isTypeDependent()) { 3783 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 3784 if (CondRes.isInvalid()) 3785 return QualType(); 3786 Cond = move(CondRes); 3787 } 3788 3789 // Assume r-value. 3790 VK = VK_RValue; 3791 OK = OK_Ordinary; 3792 3793 // Either of the arguments dependent? 3794 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 3795 return Context.DependentTy; 3796 3797 // C++0x 5.16p2 3798 // If either the second or the third operand has type (cv) void, ... 3799 QualType LTy = LHS.get()->getType(); 3800 QualType RTy = RHS.get()->getType(); 3801 bool LVoid = LTy->isVoidType(); 3802 bool RVoid = RTy->isVoidType(); 3803 if (LVoid || RVoid) { 3804 // ... then the [l2r] conversions are performed on the second and third 3805 // operands ... 3806 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 3807 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 3808 if (LHS.isInvalid() || RHS.isInvalid()) 3809 return QualType(); 3810 LTy = LHS.get()->getType(); 3811 RTy = RHS.get()->getType(); 3812 3813 // ... and one of the following shall hold: 3814 // -- The second or the third operand (but not both) is a throw- 3815 // expression; the result is of the type of the other and is an rvalue. 3816 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 3817 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 3818 if (LThrow && !RThrow) 3819 return RTy; 3820 if (RThrow && !LThrow) 3821 return LTy; 3822 3823 // -- Both the second and third operands have type void; the result is of 3824 // type void and is an rvalue. 3825 if (LVoid && RVoid) 3826 return Context.VoidTy; 3827 3828 // Neither holds, error. 3829 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 3830 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 3831 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3832 return QualType(); 3833 } 3834 3835 // Neither is void. 3836 3837 // C++0x 5.16p3 3838 // Otherwise, if the second and third operand have different types, and 3839 // either has (cv) class type, and attempt is made to convert each of those 3840 // operands to the other. 3841 if (!Context.hasSameType(LTy, RTy) && 3842 (LTy->isRecordType() || RTy->isRecordType())) { 3843 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 3844 // These return true if a single direction is already ambiguous. 3845 QualType L2RType, R2LType; 3846 bool HaveL2R, HaveR2L; 3847 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 3848 return QualType(); 3849 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 3850 return QualType(); 3851 3852 // If both can be converted, [...] the program is ill-formed. 3853 if (HaveL2R && HaveR2L) { 3854 Diag(QuestionLoc, diag::err_conditional_ambiguous) 3855 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3856 return QualType(); 3857 } 3858 3859 // If exactly one conversion is possible, that conversion is applied to 3860 // the chosen operand and the converted operands are used in place of the 3861 // original operands for the remainder of this section. 3862 if (HaveL2R) { 3863 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 3864 return QualType(); 3865 LTy = LHS.get()->getType(); 3866 } else if (HaveR2L) { 3867 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 3868 return QualType(); 3869 RTy = RHS.get()->getType(); 3870 } 3871 } 3872 3873 // C++0x 5.16p4 3874 // If the second and third operands are glvalues of the same value 3875 // category and have the same type, the result is of that type and 3876 // value category and it is a bit-field if the second or the third 3877 // operand is a bit-field, or if both are bit-fields. 3878 // We only extend this to bitfields, not to the crazy other kinds of 3879 // l-values. 3880 bool Same = Context.hasSameType(LTy, RTy); 3881 if (Same && 3882 LHS.get()->isGLValue() && 3883 LHS.get()->getValueKind() == RHS.get()->getValueKind() && 3884 LHS.get()->isOrdinaryOrBitFieldObject() && 3885 RHS.get()->isOrdinaryOrBitFieldObject()) { 3886 VK = LHS.get()->getValueKind(); 3887 if (LHS.get()->getObjectKind() == OK_BitField || 3888 RHS.get()->getObjectKind() == OK_BitField) 3889 OK = OK_BitField; 3890 return LTy; 3891 } 3892 3893 // C++0x 5.16p5 3894 // Otherwise, the result is an rvalue. If the second and third operands 3895 // do not have the same type, and either has (cv) class type, ... 3896 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 3897 // ... overload resolution is used to determine the conversions (if any) 3898 // to be applied to the operands. If the overload resolution fails, the 3899 // program is ill-formed. 3900 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 3901 return QualType(); 3902 } 3903 3904 // C++0x 5.16p6 3905 // LValue-to-rvalue, array-to-pointer, and function-to-pointer standard 3906 // conversions are performed on the second and third operands. 3907 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 3908 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 3909 if (LHS.isInvalid() || RHS.isInvalid()) 3910 return QualType(); 3911 LTy = LHS.get()->getType(); 3912 RTy = RHS.get()->getType(); 3913 3914 // After those conversions, one of the following shall hold: 3915 // -- The second and third operands have the same type; the result 3916 // is of that type. If the operands have class type, the result 3917 // is a prvalue temporary of the result type, which is 3918 // copy-initialized from either the second operand or the third 3919 // operand depending on the value of the first operand. 3920 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 3921 if (LTy->isRecordType()) { 3922 // The operands have class type. Make a temporary copy. 3923 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 3924 ExprResult LHSCopy = PerformCopyInitialization(Entity, 3925 SourceLocation(), 3926 LHS); 3927 if (LHSCopy.isInvalid()) 3928 return QualType(); 3929 3930 ExprResult RHSCopy = PerformCopyInitialization(Entity, 3931 SourceLocation(), 3932 RHS); 3933 if (RHSCopy.isInvalid()) 3934 return QualType(); 3935 3936 LHS = LHSCopy; 3937 RHS = RHSCopy; 3938 } 3939 3940 return LTy; 3941 } 3942 3943 // Extension: conditional operator involving vector types. 3944 if (LTy->isVectorType() || RTy->isVectorType()) 3945 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 3946 3947 // -- The second and third operands have arithmetic or enumeration type; 3948 // the usual arithmetic conversions are performed to bring them to a 3949 // common type, and the result is of that type. 3950 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 3951 UsualArithmeticConversions(LHS, RHS); 3952 if (LHS.isInvalid() || RHS.isInvalid()) 3953 return QualType(); 3954 return LHS.get()->getType(); 3955 } 3956 3957 // -- The second and third operands have pointer type, or one has pointer 3958 // type and the other is a null pointer constant; pointer conversions 3959 // and qualification conversions are performed to bring them to their 3960 // composite pointer type. The result is of the composite pointer type. 3961 // -- The second and third operands have pointer to member type, or one has 3962 // pointer to member type and the other is a null pointer constant; 3963 // pointer to member conversions and qualification conversions are 3964 // performed to bring them to a common type, whose cv-qualification 3965 // shall match the cv-qualification of either the second or the third 3966 // operand. The result is of the common type. 3967 bool NonStandardCompositeType = false; 3968 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 3969 isSFINAEContext()? 0 : &NonStandardCompositeType); 3970 if (!Composite.isNull()) { 3971 if (NonStandardCompositeType) 3972 Diag(QuestionLoc, 3973 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 3974 << LTy << RTy << Composite 3975 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3976 3977 return Composite; 3978 } 3979 3980 // Similarly, attempt to find composite type of two objective-c pointers. 3981 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 3982 if (!Composite.isNull()) 3983 return Composite; 3984 3985 // Check if we are using a null with a non-pointer type. 3986 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 3987 return QualType(); 3988 3989 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3990 << LHS.get()->getType() << RHS.get()->getType() 3991 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3992 return QualType(); 3993} 3994 3995/// \brief Find a merged pointer type and convert the two expressions to it. 3996/// 3997/// This finds the composite pointer type (or member pointer type) for @p E1 3998/// and @p E2 according to C++0x 5.9p2. It converts both expressions to this 3999/// type and returns it. 4000/// It does not emit diagnostics. 4001/// 4002/// \param Loc The location of the operator requiring these two expressions to 4003/// be converted to the composite pointer type. 4004/// 4005/// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4006/// a non-standard (but still sane) composite type to which both expressions 4007/// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4008/// will be set true. 4009QualType Sema::FindCompositePointerType(SourceLocation Loc, 4010 Expr *&E1, Expr *&E2, 4011 bool *NonStandardCompositeType) { 4012 if (NonStandardCompositeType) 4013 *NonStandardCompositeType = false; 4014 4015 assert(getLangOptions().CPlusPlus && "This function assumes C++"); 4016 QualType T1 = E1->getType(), T2 = E2->getType(); 4017 4018 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4019 !T2->isAnyPointerType() && !T2->isMemberPointerType()) 4020 return QualType(); 4021 4022 // C++0x 5.9p2 4023 // Pointer conversions and qualification conversions are performed on 4024 // pointer operands to bring them to their composite pointer type. If 4025 // one operand is a null pointer constant, the composite pointer type is 4026 // the type of the other operand. 4027 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4028 if (T2->isMemberPointerType()) 4029 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4030 else 4031 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4032 return T2; 4033 } 4034 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4035 if (T1->isMemberPointerType()) 4036 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4037 else 4038 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4039 return T1; 4040 } 4041 4042 // Now both have to be pointers or member pointers. 4043 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4044 (!T2->isPointerType() && !T2->isMemberPointerType())) 4045 return QualType(); 4046 4047 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4048 // the other has type "pointer to cv2 T" and the composite pointer type is 4049 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4050 // Otherwise, the composite pointer type is a pointer type similar to the 4051 // type of one of the operands, with a cv-qualification signature that is 4052 // the union of the cv-qualification signatures of the operand types. 4053 // In practice, the first part here is redundant; it's subsumed by the second. 4054 // What we do here is, we build the two possible composite types, and try the 4055 // conversions in both directions. If only one works, or if the two composite 4056 // types are the same, we have succeeded. 4057 // FIXME: extended qualifiers? 4058 typedef SmallVector<unsigned, 4> QualifierVector; 4059 QualifierVector QualifierUnion; 4060 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4061 ContainingClassVector; 4062 ContainingClassVector MemberOfClass; 4063 QualType Composite1 = Context.getCanonicalType(T1), 4064 Composite2 = Context.getCanonicalType(T2); 4065 unsigned NeedConstBefore = 0; 4066 do { 4067 const PointerType *Ptr1, *Ptr2; 4068 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4069 (Ptr2 = Composite2->getAs<PointerType>())) { 4070 Composite1 = Ptr1->getPointeeType(); 4071 Composite2 = Ptr2->getPointeeType(); 4072 4073 // If we're allowed to create a non-standard composite type, keep track 4074 // of where we need to fill in additional 'const' qualifiers. 4075 if (NonStandardCompositeType && 4076 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4077 NeedConstBefore = QualifierUnion.size(); 4078 4079 QualifierUnion.push_back( 4080 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4081 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4082 continue; 4083 } 4084 4085 const MemberPointerType *MemPtr1, *MemPtr2; 4086 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4087 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4088 Composite1 = MemPtr1->getPointeeType(); 4089 Composite2 = MemPtr2->getPointeeType(); 4090 4091 // If we're allowed to create a non-standard composite type, keep track 4092 // of where we need to fill in additional 'const' qualifiers. 4093 if (NonStandardCompositeType && 4094 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4095 NeedConstBefore = QualifierUnion.size(); 4096 4097 QualifierUnion.push_back( 4098 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4099 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4100 MemPtr2->getClass())); 4101 continue; 4102 } 4103 4104 // FIXME: block pointer types? 4105 4106 // Cannot unwrap any more types. 4107 break; 4108 } while (true); 4109 4110 if (NeedConstBefore && NonStandardCompositeType) { 4111 // Extension: Add 'const' to qualifiers that come before the first qualifier 4112 // mismatch, so that our (non-standard!) composite type meets the 4113 // requirements of C++ [conv.qual]p4 bullet 3. 4114 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4115 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4116 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4117 *NonStandardCompositeType = true; 4118 } 4119 } 4120 } 4121 4122 // Rewrap the composites as pointers or member pointers with the union CVRs. 4123 ContainingClassVector::reverse_iterator MOC 4124 = MemberOfClass.rbegin(); 4125 for (QualifierVector::reverse_iterator 4126 I = QualifierUnion.rbegin(), 4127 E = QualifierUnion.rend(); 4128 I != E; (void)++I, ++MOC) { 4129 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4130 if (MOC->first && MOC->second) { 4131 // Rebuild member pointer type 4132 Composite1 = Context.getMemberPointerType( 4133 Context.getQualifiedType(Composite1, Quals), 4134 MOC->first); 4135 Composite2 = Context.getMemberPointerType( 4136 Context.getQualifiedType(Composite2, Quals), 4137 MOC->second); 4138 } else { 4139 // Rebuild pointer type 4140 Composite1 4141 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4142 Composite2 4143 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4144 } 4145 } 4146 4147 // Try to convert to the first composite pointer type. 4148 InitializedEntity Entity1 4149 = InitializedEntity::InitializeTemporary(Composite1); 4150 InitializationKind Kind 4151 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4152 InitializationSequence E1ToC1(*this, Entity1, Kind, &E1, 1); 4153 InitializationSequence E2ToC1(*this, Entity1, Kind, &E2, 1); 4154 4155 if (E1ToC1 && E2ToC1) { 4156 // Conversion to Composite1 is viable. 4157 if (!Context.hasSameType(Composite1, Composite2)) { 4158 // Composite2 is a different type from Composite1. Check whether 4159 // Composite2 is also viable. 4160 InitializedEntity Entity2 4161 = InitializedEntity::InitializeTemporary(Composite2); 4162 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4163 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4164 if (E1ToC2 && E2ToC2) { 4165 // Both Composite1 and Composite2 are viable and are different; 4166 // this is an ambiguity. 4167 return QualType(); 4168 } 4169 } 4170 4171 // Convert E1 to Composite1 4172 ExprResult E1Result 4173 = E1ToC1.Perform(*this, Entity1, Kind, MultiExprArg(*this,&E1,1)); 4174 if (E1Result.isInvalid()) 4175 return QualType(); 4176 E1 = E1Result.takeAs<Expr>(); 4177 4178 // Convert E2 to Composite1 4179 ExprResult E2Result 4180 = E2ToC1.Perform(*this, Entity1, Kind, MultiExprArg(*this,&E2,1)); 4181 if (E2Result.isInvalid()) 4182 return QualType(); 4183 E2 = E2Result.takeAs<Expr>(); 4184 4185 return Composite1; 4186 } 4187 4188 // Check whether Composite2 is viable. 4189 InitializedEntity Entity2 4190 = InitializedEntity::InitializeTemporary(Composite2); 4191 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4192 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4193 if (!E1ToC2 || !E2ToC2) 4194 return QualType(); 4195 4196 // Convert E1 to Composite2 4197 ExprResult E1Result 4198 = E1ToC2.Perform(*this, Entity2, Kind, MultiExprArg(*this, &E1, 1)); 4199 if (E1Result.isInvalid()) 4200 return QualType(); 4201 E1 = E1Result.takeAs<Expr>(); 4202 4203 // Convert E2 to Composite2 4204 ExprResult E2Result 4205 = E2ToC2.Perform(*this, Entity2, Kind, MultiExprArg(*this, &E2, 1)); 4206 if (E2Result.isInvalid()) 4207 return QualType(); 4208 E2 = E2Result.takeAs<Expr>(); 4209 4210 return Composite2; 4211} 4212 4213ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4214 if (!E) 4215 return ExprError(); 4216 4217 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4218 4219 // If the result is a glvalue, we shouldn't bind it. 4220 if (!E->isRValue()) 4221 return Owned(E); 4222 4223 // In ARC, calls that return a retainable type can return retained, 4224 // in which case we have to insert a consuming cast. 4225 if (getLangOptions().ObjCAutoRefCount && 4226 E->getType()->isObjCRetainableType()) { 4227 4228 bool ReturnsRetained; 4229 4230 // For actual calls, we compute this by examining the type of the 4231 // called value. 4232 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4233 Expr *Callee = Call->getCallee()->IgnoreParens(); 4234 QualType T = Callee->getType(); 4235 4236 if (T == Context.BoundMemberTy) { 4237 // Handle pointer-to-members. 4238 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4239 T = BinOp->getRHS()->getType(); 4240 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4241 T = Mem->getMemberDecl()->getType(); 4242 } 4243 4244 if (const PointerType *Ptr = T->getAs<PointerType>()) 4245 T = Ptr->getPointeeType(); 4246 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4247 T = Ptr->getPointeeType(); 4248 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4249 T = MemPtr->getPointeeType(); 4250 4251 const FunctionType *FTy = T->getAs<FunctionType>(); 4252 assert(FTy && "call to value not of function type?"); 4253 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4254 4255 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4256 // type always produce a +1 object. 4257 } else if (isa<StmtExpr>(E)) { 4258 ReturnsRetained = true; 4259 4260 // For message sends and property references, we try to find an 4261 // actual method. FIXME: we should infer retention by selector in 4262 // cases where we don't have an actual method. 4263 } else { 4264 ObjCMethodDecl *D = 0; 4265 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4266 D = Send->getMethodDecl(); 4267 } 4268 4269 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4270 4271 // Don't do reclaims on performSelector calls; despite their 4272 // return type, the invoked method doesn't necessarily actually 4273 // return an object. 4274 if (!ReturnsRetained && 4275 D && D->getMethodFamily() == OMF_performSelector) 4276 return Owned(E); 4277 } 4278 4279 // Don't reclaim an object of Class type. 4280 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4281 return Owned(E); 4282 4283 ExprNeedsCleanups = true; 4284 4285 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4286 : CK_ARCReclaimReturnedObject); 4287 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4288 VK_RValue)); 4289 } 4290 4291 if (!getLangOptions().CPlusPlus) 4292 return Owned(E); 4293 4294 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4295 // a fast path for the common case that the type is directly a RecordType. 4296 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4297 const RecordType *RT = 0; 4298 while (!RT) { 4299 switch (T->getTypeClass()) { 4300 case Type::Record: 4301 RT = cast<RecordType>(T); 4302 break; 4303 case Type::ConstantArray: 4304 case Type::IncompleteArray: 4305 case Type::VariableArray: 4306 case Type::DependentSizedArray: 4307 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4308 break; 4309 default: 4310 return Owned(E); 4311 } 4312 } 4313 4314 // That should be enough to guarantee that this type is complete. 4315 // If it has a trivial destructor, we can avoid the extra copy. 4316 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4317 if (RD->isInvalidDecl() || RD->hasTrivialDestructor()) 4318 return Owned(E); 4319 4320 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4321 4322 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4323 if (Destructor) { 4324 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4325 CheckDestructorAccess(E->getExprLoc(), Destructor, 4326 PDiag(diag::err_access_dtor_temp) 4327 << E->getType()); 4328 4329 // We need a cleanup, but we don't need to remember the temporary. 4330 ExprNeedsCleanups = true; 4331 } 4332 return Owned(CXXBindTemporaryExpr::Create(Context, Temp, E)); 4333} 4334 4335ExprResult 4336Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4337 if (SubExpr.isInvalid()) 4338 return ExprError(); 4339 4340 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4341} 4342 4343Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4344 assert(SubExpr && "sub expression can't be null!"); 4345 4346 CleanupVarDeclMarking(); 4347 4348 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4349 assert(ExprCleanupObjects.size() >= FirstCleanup); 4350 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4351 if (!ExprNeedsCleanups) 4352 return SubExpr; 4353 4354 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4355 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4356 ExprCleanupObjects.size() - FirstCleanup); 4357 4358 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4359 DiscardCleanupsInEvaluationContext(); 4360 4361 return E; 4362} 4363 4364Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4365 assert(SubStmt && "sub statement can't be null!"); 4366 4367 CleanupVarDeclMarking(); 4368 4369 if (!ExprNeedsCleanups) 4370 return SubStmt; 4371 4372 // FIXME: In order to attach the temporaries, wrap the statement into 4373 // a StmtExpr; currently this is only used for asm statements. 4374 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4375 // a new AsmStmtWithTemporaries. 4376 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, &SubStmt, 1, 4377 SourceLocation(), 4378 SourceLocation()); 4379 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4380 SourceLocation()); 4381 return MaybeCreateExprWithCleanups(E); 4382} 4383 4384ExprResult 4385Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4386 tok::TokenKind OpKind, ParsedType &ObjectType, 4387 bool &MayBePseudoDestructor) { 4388 // Since this might be a postfix expression, get rid of ParenListExprs. 4389 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4390 if (Result.isInvalid()) return ExprError(); 4391 Base = Result.get(); 4392 4393 Result = CheckPlaceholderExpr(Base); 4394 if (Result.isInvalid()) return ExprError(); 4395 Base = Result.take(); 4396 4397 QualType BaseType = Base->getType(); 4398 MayBePseudoDestructor = false; 4399 if (BaseType->isDependentType()) { 4400 // If we have a pointer to a dependent type and are using the -> operator, 4401 // the object type is the type that the pointer points to. We might still 4402 // have enough information about that type to do something useful. 4403 if (OpKind == tok::arrow) 4404 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 4405 BaseType = Ptr->getPointeeType(); 4406 4407 ObjectType = ParsedType::make(BaseType); 4408 MayBePseudoDestructor = true; 4409 return Owned(Base); 4410 } 4411 4412 // C++ [over.match.oper]p8: 4413 // [...] When operator->returns, the operator-> is applied to the value 4414 // returned, with the original second operand. 4415 if (OpKind == tok::arrow) { 4416 // The set of types we've considered so far. 4417 llvm::SmallPtrSet<CanQualType,8> CTypes; 4418 SmallVector<SourceLocation, 8> Locations; 4419 CTypes.insert(Context.getCanonicalType(BaseType)); 4420 4421 while (BaseType->isRecordType()) { 4422 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 4423 if (Result.isInvalid()) 4424 return ExprError(); 4425 Base = Result.get(); 4426 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 4427 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 4428 BaseType = Base->getType(); 4429 CanQualType CBaseType = Context.getCanonicalType(BaseType); 4430 if (!CTypes.insert(CBaseType)) { 4431 Diag(OpLoc, diag::err_operator_arrow_circular); 4432 for (unsigned i = 0; i < Locations.size(); i++) 4433 Diag(Locations[i], diag::note_declared_at); 4434 return ExprError(); 4435 } 4436 } 4437 4438 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 4439 BaseType = BaseType->getPointeeType(); 4440 } 4441 4442 // Objective-C properties allow "." access on Objective-C pointer types, 4443 // so adjust the base type to the object type itself. 4444 if (BaseType->isObjCObjectPointerType()) 4445 BaseType = BaseType->getPointeeType(); 4446 4447 // C++ [basic.lookup.classref]p2: 4448 // [...] If the type of the object expression is of pointer to scalar 4449 // type, the unqualified-id is looked up in the context of the complete 4450 // postfix-expression. 4451 // 4452 // This also indicates that we could be parsing a pseudo-destructor-name. 4453 // Note that Objective-C class and object types can be pseudo-destructor 4454 // expressions or normal member (ivar or property) access expressions. 4455 if (BaseType->isObjCObjectOrInterfaceType()) { 4456 MayBePseudoDestructor = true; 4457 } else if (!BaseType->isRecordType()) { 4458 ObjectType = ParsedType(); 4459 MayBePseudoDestructor = true; 4460 return Owned(Base); 4461 } 4462 4463 // The object type must be complete (or dependent). 4464 if (!BaseType->isDependentType() && 4465 RequireCompleteType(OpLoc, BaseType, 4466 PDiag(diag::err_incomplete_member_access))) 4467 return ExprError(); 4468 4469 // C++ [basic.lookup.classref]p2: 4470 // If the id-expression in a class member access (5.2.5) is an 4471 // unqualified-id, and the type of the object expression is of a class 4472 // type C (or of pointer to a class type C), the unqualified-id is looked 4473 // up in the scope of class C. [...] 4474 ObjectType = ParsedType::make(BaseType); 4475 return move(Base); 4476} 4477 4478ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 4479 Expr *MemExpr) { 4480 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 4481 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 4482 << isa<CXXPseudoDestructorExpr>(MemExpr) 4483 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 4484 4485 return ActOnCallExpr(/*Scope*/ 0, 4486 MemExpr, 4487 /*LPLoc*/ ExpectedLParenLoc, 4488 MultiExprArg(), 4489 /*RPLoc*/ ExpectedLParenLoc); 4490} 4491 4492static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 4493 tok::TokenKind& OpKind, SourceLocation OpLoc) { 4494 if (Base->hasPlaceholderType()) { 4495 ExprResult result = S.CheckPlaceholderExpr(Base); 4496 if (result.isInvalid()) return true; 4497 Base = result.take(); 4498 } 4499 ObjectType = Base->getType(); 4500 4501 // C++ [expr.pseudo]p2: 4502 // The left-hand side of the dot operator shall be of scalar type. The 4503 // left-hand side of the arrow operator shall be of pointer to scalar type. 4504 // This scalar type is the object type. 4505 // Note that this is rather different from the normal handling for the 4506 // arrow operator. 4507 if (OpKind == tok::arrow) { 4508 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 4509 ObjectType = Ptr->getPointeeType(); 4510 } else if (!Base->isTypeDependent()) { 4511 // The user wrote "p->" when she probably meant "p."; fix it. 4512 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 4513 << ObjectType << true 4514 << FixItHint::CreateReplacement(OpLoc, "."); 4515 if (S.isSFINAEContext()) 4516 return true; 4517 4518 OpKind = tok::period; 4519 } 4520 } 4521 4522 return false; 4523} 4524 4525ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 4526 SourceLocation OpLoc, 4527 tok::TokenKind OpKind, 4528 const CXXScopeSpec &SS, 4529 TypeSourceInfo *ScopeTypeInfo, 4530 SourceLocation CCLoc, 4531 SourceLocation TildeLoc, 4532 PseudoDestructorTypeStorage Destructed, 4533 bool HasTrailingLParen) { 4534 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 4535 4536 QualType ObjectType; 4537 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4538 return ExprError(); 4539 4540 if (!ObjectType->isDependentType() && !ObjectType->isScalarType()) { 4541 if (getLangOptions().MicrosoftMode && ObjectType->isVoidType()) 4542 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 4543 else 4544 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 4545 << ObjectType << Base->getSourceRange(); 4546 return ExprError(); 4547 } 4548 4549 // C++ [expr.pseudo]p2: 4550 // [...] The cv-unqualified versions of the object type and of the type 4551 // designated by the pseudo-destructor-name shall be the same type. 4552 if (DestructedTypeInfo) { 4553 QualType DestructedType = DestructedTypeInfo->getType(); 4554 SourceLocation DestructedTypeStart 4555 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 4556 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 4557 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 4558 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 4559 << ObjectType << DestructedType << Base->getSourceRange() 4560 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 4561 4562 // Recover by setting the destructed type to the object type. 4563 DestructedType = ObjectType; 4564 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 4565 DestructedTypeStart); 4566 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 4567 } else if (DestructedType.getObjCLifetime() != 4568 ObjectType.getObjCLifetime()) { 4569 4570 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 4571 // Okay: just pretend that the user provided the correctly-qualified 4572 // type. 4573 } else { 4574 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 4575 << ObjectType << DestructedType << Base->getSourceRange() 4576 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 4577 } 4578 4579 // Recover by setting the destructed type to the object type. 4580 DestructedType = ObjectType; 4581 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 4582 DestructedTypeStart); 4583 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 4584 } 4585 } 4586 } 4587 4588 // C++ [expr.pseudo]p2: 4589 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 4590 // form 4591 // 4592 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 4593 // 4594 // shall designate the same scalar type. 4595 if (ScopeTypeInfo) { 4596 QualType ScopeType = ScopeTypeInfo->getType(); 4597 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 4598 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 4599 4600 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 4601 diag::err_pseudo_dtor_type_mismatch) 4602 << ObjectType << ScopeType << Base->getSourceRange() 4603 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 4604 4605 ScopeType = QualType(); 4606 ScopeTypeInfo = 0; 4607 } 4608 } 4609 4610 Expr *Result 4611 = new (Context) CXXPseudoDestructorExpr(Context, Base, 4612 OpKind == tok::arrow, OpLoc, 4613 SS.getWithLocInContext(Context), 4614 ScopeTypeInfo, 4615 CCLoc, 4616 TildeLoc, 4617 Destructed); 4618 4619 if (HasTrailingLParen) 4620 return Owned(Result); 4621 4622 return DiagnoseDtorReference(Destructed.getLocation(), Result); 4623} 4624 4625ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 4626 SourceLocation OpLoc, 4627 tok::TokenKind OpKind, 4628 CXXScopeSpec &SS, 4629 UnqualifiedId &FirstTypeName, 4630 SourceLocation CCLoc, 4631 SourceLocation TildeLoc, 4632 UnqualifiedId &SecondTypeName, 4633 bool HasTrailingLParen) { 4634 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4635 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 4636 "Invalid first type name in pseudo-destructor"); 4637 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4638 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 4639 "Invalid second type name in pseudo-destructor"); 4640 4641 QualType ObjectType; 4642 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4643 return ExprError(); 4644 4645 // Compute the object type that we should use for name lookup purposes. Only 4646 // record types and dependent types matter. 4647 ParsedType ObjectTypePtrForLookup; 4648 if (!SS.isSet()) { 4649 if (ObjectType->isRecordType()) 4650 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 4651 else if (ObjectType->isDependentType()) 4652 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 4653 } 4654 4655 // Convert the name of the type being destructed (following the ~) into a 4656 // type (with source-location information). 4657 QualType DestructedType; 4658 TypeSourceInfo *DestructedTypeInfo = 0; 4659 PseudoDestructorTypeStorage Destructed; 4660 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 4661 ParsedType T = getTypeName(*SecondTypeName.Identifier, 4662 SecondTypeName.StartLocation, 4663 S, &SS, true, false, ObjectTypePtrForLookup); 4664 if (!T && 4665 ((SS.isSet() && !computeDeclContext(SS, false)) || 4666 (!SS.isSet() && ObjectType->isDependentType()))) { 4667 // The name of the type being destroyed is a dependent name, and we 4668 // couldn't find anything useful in scope. Just store the identifier and 4669 // it's location, and we'll perform (qualified) name lookup again at 4670 // template instantiation time. 4671 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 4672 SecondTypeName.StartLocation); 4673 } else if (!T) { 4674 Diag(SecondTypeName.StartLocation, 4675 diag::err_pseudo_dtor_destructor_non_type) 4676 << SecondTypeName.Identifier << ObjectType; 4677 if (isSFINAEContext()) 4678 return ExprError(); 4679 4680 // Recover by assuming we had the right type all along. 4681 DestructedType = ObjectType; 4682 } else 4683 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 4684 } else { 4685 // Resolve the template-id to a type. 4686 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 4687 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4688 TemplateId->getTemplateArgs(), 4689 TemplateId->NumArgs); 4690 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 4691 TemplateId->TemplateKWLoc, 4692 TemplateId->Template, 4693 TemplateId->TemplateNameLoc, 4694 TemplateId->LAngleLoc, 4695 TemplateArgsPtr, 4696 TemplateId->RAngleLoc); 4697 if (T.isInvalid() || !T.get()) { 4698 // Recover by assuming we had the right type all along. 4699 DestructedType = ObjectType; 4700 } else 4701 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 4702 } 4703 4704 // If we've performed some kind of recovery, (re-)build the type source 4705 // information. 4706 if (!DestructedType.isNull()) { 4707 if (!DestructedTypeInfo) 4708 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 4709 SecondTypeName.StartLocation); 4710 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 4711 } 4712 4713 // Convert the name of the scope type (the type prior to '::') into a type. 4714 TypeSourceInfo *ScopeTypeInfo = 0; 4715 QualType ScopeType; 4716 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4717 FirstTypeName.Identifier) { 4718 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 4719 ParsedType T = getTypeName(*FirstTypeName.Identifier, 4720 FirstTypeName.StartLocation, 4721 S, &SS, true, false, ObjectTypePtrForLookup); 4722 if (!T) { 4723 Diag(FirstTypeName.StartLocation, 4724 diag::err_pseudo_dtor_destructor_non_type) 4725 << FirstTypeName.Identifier << ObjectType; 4726 4727 if (isSFINAEContext()) 4728 return ExprError(); 4729 4730 // Just drop this type. It's unnecessary anyway. 4731 ScopeType = QualType(); 4732 } else 4733 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 4734 } else { 4735 // Resolve the template-id to a type. 4736 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 4737 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4738 TemplateId->getTemplateArgs(), 4739 TemplateId->NumArgs); 4740 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 4741 TemplateId->TemplateKWLoc, 4742 TemplateId->Template, 4743 TemplateId->TemplateNameLoc, 4744 TemplateId->LAngleLoc, 4745 TemplateArgsPtr, 4746 TemplateId->RAngleLoc); 4747 if (T.isInvalid() || !T.get()) { 4748 // Recover by dropping this type. 4749 ScopeType = QualType(); 4750 } else 4751 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 4752 } 4753 } 4754 4755 if (!ScopeType.isNull() && !ScopeTypeInfo) 4756 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 4757 FirstTypeName.StartLocation); 4758 4759 4760 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 4761 ScopeTypeInfo, CCLoc, TildeLoc, 4762 Destructed, HasTrailingLParen); 4763} 4764 4765ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 4766 SourceLocation OpLoc, 4767 tok::TokenKind OpKind, 4768 SourceLocation TildeLoc, 4769 const DeclSpec& DS, 4770 bool HasTrailingLParen) { 4771 QualType ObjectType; 4772 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4773 return ExprError(); 4774 4775 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 4776 4777 TypeLocBuilder TLB; 4778 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 4779 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 4780 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 4781 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 4782 4783 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 4784 0, SourceLocation(), TildeLoc, 4785 Destructed, HasTrailingLParen); 4786} 4787 4788ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 4789 CXXMethodDecl *Method, 4790 bool HadMultipleCandidates) { 4791 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 4792 FoundDecl, Method); 4793 if (Exp.isInvalid()) 4794 return true; 4795 4796 MemberExpr *ME = 4797 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 4798 SourceLocation(), Context.BoundMemberTy, 4799 VK_RValue, OK_Ordinary); 4800 if (HadMultipleCandidates) 4801 ME->setHadMultipleCandidates(true); 4802 4803 QualType ResultType = Method->getResultType(); 4804 ExprValueKind VK = Expr::getValueKindForType(ResultType); 4805 ResultType = ResultType.getNonLValueExprType(Context); 4806 4807 MarkFunctionReferenced(Exp.get()->getLocStart(), Method); 4808 CXXMemberCallExpr *CE = 4809 new (Context) CXXMemberCallExpr(Context, ME, 0, 0, ResultType, VK, 4810 Exp.get()->getLocEnd()); 4811 return CE; 4812} 4813 4814ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 4815 SourceLocation RParen) { 4816 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 4817 Operand->CanThrow(Context), 4818 KeyLoc, RParen)); 4819} 4820 4821ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 4822 Expr *Operand, SourceLocation RParen) { 4823 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 4824} 4825 4826/// Perform the conversions required for an expression used in a 4827/// context that ignores the result. 4828ExprResult Sema::IgnoredValueConversions(Expr *E) { 4829 if (E->hasPlaceholderType()) { 4830 ExprResult result = CheckPlaceholderExpr(E); 4831 if (result.isInvalid()) return Owned(E); 4832 E = result.take(); 4833 } 4834 4835 // C99 6.3.2.1: 4836 // [Except in specific positions,] an lvalue that does not have 4837 // array type is converted to the value stored in the 4838 // designated object (and is no longer an lvalue). 4839 if (E->isRValue()) { 4840 // In C, function designators (i.e. expressions of function type) 4841 // are r-values, but we still want to do function-to-pointer decay 4842 // on them. This is both technically correct and convenient for 4843 // some clients. 4844 if (!getLangOptions().CPlusPlus && E->getType()->isFunctionType()) 4845 return DefaultFunctionArrayConversion(E); 4846 4847 return Owned(E); 4848 } 4849 4850 // Otherwise, this rule does not apply in C++, at least not for the moment. 4851 if (getLangOptions().CPlusPlus) return Owned(E); 4852 4853 // GCC seems to also exclude expressions of incomplete enum type. 4854 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 4855 if (!T->getDecl()->isComplete()) { 4856 // FIXME: stupid workaround for a codegen bug! 4857 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 4858 return Owned(E); 4859 } 4860 } 4861 4862 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 4863 if (Res.isInvalid()) 4864 return Owned(E); 4865 E = Res.take(); 4866 4867 if (!E->getType()->isVoidType()) 4868 RequireCompleteType(E->getExprLoc(), E->getType(), 4869 diag::err_incomplete_type); 4870 return Owned(E); 4871} 4872 4873ExprResult Sema::ActOnFinishFullExpr(Expr *FE) { 4874 ExprResult FullExpr = Owned(FE); 4875 4876 if (!FullExpr.get()) 4877 return ExprError(); 4878 4879 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 4880 return ExprError(); 4881 4882 // Top-level message sends default to 'id' when we're in a debugger. 4883 if (getLangOptions().DebuggerCastResultToId && 4884 FullExpr.get()->getType() == Context.UnknownAnyTy && 4885 isa<ObjCMessageExpr>(FullExpr.get())) { 4886 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 4887 if (FullExpr.isInvalid()) 4888 return ExprError(); 4889 } 4890 4891 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 4892 if (FullExpr.isInvalid()) 4893 return ExprError(); 4894 4895 FullExpr = IgnoredValueConversions(FullExpr.take()); 4896 if (FullExpr.isInvalid()) 4897 return ExprError(); 4898 4899 CheckImplicitConversions(FullExpr.get(), FullExpr.get()->getExprLoc()); 4900 return MaybeCreateExprWithCleanups(FullExpr); 4901} 4902 4903StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 4904 if (!FullStmt) return StmtError(); 4905 4906 return MaybeCreateStmtWithCleanups(FullStmt); 4907} 4908 4909Sema::IfExistsResult 4910Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 4911 CXXScopeSpec &SS, 4912 const DeclarationNameInfo &TargetNameInfo) { 4913 DeclarationName TargetName = TargetNameInfo.getName(); 4914 if (!TargetName) 4915 return IER_DoesNotExist; 4916 4917 // If the name itself is dependent, then the result is dependent. 4918 if (TargetName.isDependentName()) 4919 return IER_Dependent; 4920 4921 // Do the redeclaration lookup in the current scope. 4922 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 4923 Sema::NotForRedeclaration); 4924 LookupParsedName(R, S, &SS); 4925 R.suppressDiagnostics(); 4926 4927 switch (R.getResultKind()) { 4928 case LookupResult::Found: 4929 case LookupResult::FoundOverloaded: 4930 case LookupResult::FoundUnresolvedValue: 4931 case LookupResult::Ambiguous: 4932 return IER_Exists; 4933 4934 case LookupResult::NotFound: 4935 return IER_DoesNotExist; 4936 4937 case LookupResult::NotFoundInCurrentInstantiation: 4938 return IER_Dependent; 4939 } 4940 4941 llvm_unreachable("Invalid LookupResult Kind!"); 4942} 4943 4944Sema::IfExistsResult 4945Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 4946 bool IsIfExists, CXXScopeSpec &SS, 4947 UnqualifiedId &Name) { 4948 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 4949 4950 // Check for unexpanded parameter packs. 4951 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 4952 collectUnexpandedParameterPacks(SS, Unexpanded); 4953 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 4954 if (!Unexpanded.empty()) { 4955 DiagnoseUnexpandedParameterPacks(KeywordLoc, 4956 IsIfExists? UPPC_IfExists 4957 : UPPC_IfNotExists, 4958 Unexpanded); 4959 return IER_Error; 4960 } 4961 4962 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 4963} 4964