SemaExprCXX.cpp revision 6959acd4bb0979361365e675968173ede7183489
1//===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9/// 10/// \file 11/// \brief Implements semantic analysis for C++ expressions. 12/// 13//===----------------------------------------------------------------------===// 14 15#include "clang/Sema/SemaInternal.h" 16#include "TypeLocBuilder.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/CXXInheritance.h" 19#include "clang/AST/CharUnits.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/EvaluatedExprVisitor.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/ExprObjC.h" 24#include "clang/AST/TypeLoc.h" 25#include "clang/Basic/PartialDiagnostic.h" 26#include "clang/Basic/TargetInfo.h" 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Sema/DeclSpec.h" 29#include "clang/Sema/Initialization.h" 30#include "clang/Sema/Lookup.h" 31#include "clang/Sema/ParsedTemplate.h" 32#include "clang/Sema/Scope.h" 33#include "clang/Sema/ScopeInfo.h" 34#include "clang/Sema/TemplateDeduction.h" 35#include "llvm/ADT/APInt.h" 36#include "llvm/ADT/STLExtras.h" 37#include "llvm/Support/ErrorHandling.h" 38using namespace clang; 39using namespace sema; 40 41ParsedType Sema::getDestructorName(SourceLocation TildeLoc, 42 IdentifierInfo &II, 43 SourceLocation NameLoc, 44 Scope *S, CXXScopeSpec &SS, 45 ParsedType ObjectTypePtr, 46 bool EnteringContext) { 47 // Determine where to perform name lookup. 48 49 // FIXME: This area of the standard is very messy, and the current 50 // wording is rather unclear about which scopes we search for the 51 // destructor name; see core issues 399 and 555. Issue 399 in 52 // particular shows where the current description of destructor name 53 // lookup is completely out of line with existing practice, e.g., 54 // this appears to be ill-formed: 55 // 56 // namespace N { 57 // template <typename T> struct S { 58 // ~S(); 59 // }; 60 // } 61 // 62 // void f(N::S<int>* s) { 63 // s->N::S<int>::~S(); 64 // } 65 // 66 // See also PR6358 and PR6359. 67 // For this reason, we're currently only doing the C++03 version of this 68 // code; the C++0x version has to wait until we get a proper spec. 69 QualType SearchType; 70 DeclContext *LookupCtx = 0; 71 bool isDependent = false; 72 bool LookInScope = false; 73 74 // If we have an object type, it's because we are in a 75 // pseudo-destructor-expression or a member access expression, and 76 // we know what type we're looking for. 77 if (ObjectTypePtr) 78 SearchType = GetTypeFromParser(ObjectTypePtr); 79 80 if (SS.isSet()) { 81 NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 82 83 bool AlreadySearched = false; 84 bool LookAtPrefix = true; 85 // C++ [basic.lookup.qual]p6: 86 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier, 87 // the type-names are looked up as types in the scope designated by the 88 // nested-name-specifier. In a qualified-id of the form: 89 // 90 // ::[opt] nested-name-specifier ~ class-name 91 // 92 // where the nested-name-specifier designates a namespace scope, and in 93 // a qualified-id of the form: 94 // 95 // ::opt nested-name-specifier class-name :: ~ class-name 96 // 97 // the class-names are looked up as types in the scope designated by 98 // the nested-name-specifier. 99 // 100 // Here, we check the first case (completely) and determine whether the 101 // code below is permitted to look at the prefix of the 102 // nested-name-specifier. 103 DeclContext *DC = computeDeclContext(SS, EnteringContext); 104 if (DC && DC->isFileContext()) { 105 AlreadySearched = true; 106 LookupCtx = DC; 107 isDependent = false; 108 } else if (DC && isa<CXXRecordDecl>(DC)) 109 LookAtPrefix = false; 110 111 // The second case from the C++03 rules quoted further above. 112 NestedNameSpecifier *Prefix = 0; 113 if (AlreadySearched) { 114 // Nothing left to do. 115 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) { 116 CXXScopeSpec PrefixSS; 117 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data())); 118 LookupCtx = computeDeclContext(PrefixSS, EnteringContext); 119 isDependent = isDependentScopeSpecifier(PrefixSS); 120 } else if (ObjectTypePtr) { 121 LookupCtx = computeDeclContext(SearchType); 122 isDependent = SearchType->isDependentType(); 123 } else { 124 LookupCtx = computeDeclContext(SS, EnteringContext); 125 isDependent = LookupCtx && LookupCtx->isDependentContext(); 126 } 127 128 LookInScope = false; 129 } else if (ObjectTypePtr) { 130 // C++ [basic.lookup.classref]p3: 131 // If the unqualified-id is ~type-name, the type-name is looked up 132 // in the context of the entire postfix-expression. If the type T 133 // of the object expression is of a class type C, the type-name is 134 // also looked up in the scope of class C. At least one of the 135 // lookups shall find a name that refers to (possibly 136 // cv-qualified) T. 137 LookupCtx = computeDeclContext(SearchType); 138 isDependent = SearchType->isDependentType(); 139 assert((isDependent || !SearchType->isIncompleteType()) && 140 "Caller should have completed object type"); 141 142 LookInScope = true; 143 } else { 144 // Perform lookup into the current scope (only). 145 LookInScope = true; 146 } 147 148 TypeDecl *NonMatchingTypeDecl = 0; 149 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName); 150 for (unsigned Step = 0; Step != 2; ++Step) { 151 // Look for the name first in the computed lookup context (if we 152 // have one) and, if that fails to find a match, in the scope (if 153 // we're allowed to look there). 154 Found.clear(); 155 if (Step == 0 && LookupCtx) 156 LookupQualifiedName(Found, LookupCtx); 157 else if (Step == 1 && LookInScope && S) 158 LookupName(Found, S); 159 else 160 continue; 161 162 // FIXME: Should we be suppressing ambiguities here? 163 if (Found.isAmbiguous()) 164 return ParsedType(); 165 166 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) { 167 QualType T = Context.getTypeDeclType(Type); 168 169 if (SearchType.isNull() || SearchType->isDependentType() || 170 Context.hasSameUnqualifiedType(T, SearchType)) { 171 // We found our type! 172 173 return ParsedType::make(T); 174 } 175 176 if (!SearchType.isNull()) 177 NonMatchingTypeDecl = Type; 178 } 179 180 // If the name that we found is a class template name, and it is 181 // the same name as the template name in the last part of the 182 // nested-name-specifier (if present) or the object type, then 183 // this is the destructor for that class. 184 // FIXME: This is a workaround until we get real drafting for core 185 // issue 399, for which there isn't even an obvious direction. 186 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) { 187 QualType MemberOfType; 188 if (SS.isSet()) { 189 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) { 190 // Figure out the type of the context, if it has one. 191 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) 192 MemberOfType = Context.getTypeDeclType(Record); 193 } 194 } 195 if (MemberOfType.isNull()) 196 MemberOfType = SearchType; 197 198 if (MemberOfType.isNull()) 199 continue; 200 201 // We're referring into a class template specialization. If the 202 // class template we found is the same as the template being 203 // specialized, we found what we are looking for. 204 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) { 205 if (ClassTemplateSpecializationDecl *Spec 206 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) { 207 if (Spec->getSpecializedTemplate()->getCanonicalDecl() == 208 Template->getCanonicalDecl()) 209 return ParsedType::make(MemberOfType); 210 } 211 212 continue; 213 } 214 215 // We're referring to an unresolved class template 216 // specialization. Determine whether we class template we found 217 // is the same as the template being specialized or, if we don't 218 // know which template is being specialized, that it at least 219 // has the same name. 220 if (const TemplateSpecializationType *SpecType 221 = MemberOfType->getAs<TemplateSpecializationType>()) { 222 TemplateName SpecName = SpecType->getTemplateName(); 223 224 // The class template we found is the same template being 225 // specialized. 226 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) { 227 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl()) 228 return ParsedType::make(MemberOfType); 229 230 continue; 231 } 232 233 // The class template we found has the same name as the 234 // (dependent) template name being specialized. 235 if (DependentTemplateName *DepTemplate 236 = SpecName.getAsDependentTemplateName()) { 237 if (DepTemplate->isIdentifier() && 238 DepTemplate->getIdentifier() == Template->getIdentifier()) 239 return ParsedType::make(MemberOfType); 240 241 continue; 242 } 243 } 244 } 245 } 246 247 if (isDependent) { 248 // We didn't find our type, but that's okay: it's dependent 249 // anyway. 250 251 // FIXME: What if we have no nested-name-specifier? 252 QualType T = CheckTypenameType(ETK_None, SourceLocation(), 253 SS.getWithLocInContext(Context), 254 II, NameLoc); 255 return ParsedType::make(T); 256 } 257 258 if (NonMatchingTypeDecl) { 259 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl); 260 Diag(NameLoc, diag::err_destructor_expr_type_mismatch) 261 << T << SearchType; 262 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here) 263 << T; 264 } else if (ObjectTypePtr) 265 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type) 266 << &II; 267 else 268 Diag(NameLoc, diag::err_destructor_class_name); 269 270 return ParsedType(); 271} 272 273ParsedType Sema::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) { 274 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType) 275 return ParsedType(); 276 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype 277 && "only get destructor types from declspecs"); 278 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 279 QualType SearchType = GetTypeFromParser(ObjectType); 280 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) { 281 return ParsedType::make(T); 282 } 283 284 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch) 285 << T << SearchType; 286 return ParsedType(); 287} 288 289/// \brief Build a C++ typeid expression with a type operand. 290ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 291 SourceLocation TypeidLoc, 292 TypeSourceInfo *Operand, 293 SourceLocation RParenLoc) { 294 // C++ [expr.typeid]p4: 295 // The top-level cv-qualifiers of the lvalue expression or the type-id 296 // that is the operand of typeid are always ignored. 297 // If the type of the type-id is a class type or a reference to a class 298 // type, the class shall be completely-defined. 299 Qualifiers Quals; 300 QualType T 301 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(), 302 Quals); 303 if (T->getAs<RecordType>() && 304 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 305 return ExprError(); 306 307 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 308 Operand, 309 SourceRange(TypeidLoc, RParenLoc))); 310} 311 312/// \brief Build a C++ typeid expression with an expression operand. 313ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 314 SourceLocation TypeidLoc, 315 Expr *E, 316 SourceLocation RParenLoc) { 317 if (E && !E->isTypeDependent()) { 318 if (E->getType()->isPlaceholderType()) { 319 ExprResult result = CheckPlaceholderExpr(E); 320 if (result.isInvalid()) return ExprError(); 321 E = result.take(); 322 } 323 324 QualType T = E->getType(); 325 if (const RecordType *RecordT = T->getAs<RecordType>()) { 326 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl()); 327 // C++ [expr.typeid]p3: 328 // [...] If the type of the expression is a class type, the class 329 // shall be completely-defined. 330 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 331 return ExprError(); 332 333 // C++ [expr.typeid]p3: 334 // When typeid is applied to an expression other than an glvalue of a 335 // polymorphic class type [...] [the] expression is an unevaluated 336 // operand. [...] 337 if (RecordD->isPolymorphic() && E->isGLValue()) { 338 // The subexpression is potentially evaluated; switch the context 339 // and recheck the subexpression. 340 ExprResult Result = TransformToPotentiallyEvaluated(E); 341 if (Result.isInvalid()) return ExprError(); 342 E = Result.take(); 343 344 // We require a vtable to query the type at run time. 345 MarkVTableUsed(TypeidLoc, RecordD); 346 } 347 } 348 349 // C++ [expr.typeid]p4: 350 // [...] If the type of the type-id is a reference to a possibly 351 // cv-qualified type, the result of the typeid expression refers to a 352 // std::type_info object representing the cv-unqualified referenced 353 // type. 354 Qualifiers Quals; 355 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals); 356 if (!Context.hasSameType(T, UnqualT)) { 357 T = UnqualT; 358 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).take(); 359 } 360 } 361 362 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 363 E, 364 SourceRange(TypeidLoc, RParenLoc))); 365} 366 367/// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression); 368ExprResult 369Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc, 370 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 371 // Find the std::type_info type. 372 if (!getStdNamespace()) 373 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 374 375 if (!CXXTypeInfoDecl) { 376 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info"); 377 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName); 378 LookupQualifiedName(R, getStdNamespace()); 379 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 380 // Microsoft's typeinfo doesn't have type_info in std but in the global 381 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153. 382 if (!CXXTypeInfoDecl && LangOpts.MicrosoftMode) { 383 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 384 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 385 } 386 if (!CXXTypeInfoDecl) 387 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 388 } 389 390 if (!getLangOpts().RTTI) { 391 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti)); 392 } 393 394 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl); 395 396 if (isType) { 397 // The operand is a type; handle it as such. 398 TypeSourceInfo *TInfo = 0; 399 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 400 &TInfo); 401 if (T.isNull()) 402 return ExprError(); 403 404 if (!TInfo) 405 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 406 407 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc); 408 } 409 410 // The operand is an expression. 411 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 412} 413 414/// \brief Build a Microsoft __uuidof expression with a type operand. 415ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 416 SourceLocation TypeidLoc, 417 TypeSourceInfo *Operand, 418 SourceLocation RParenLoc) { 419 if (!Operand->getType()->isDependentType()) { 420 if (!CXXUuidofExpr::GetUuidAttrOfType(Operand->getType())) 421 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 422 } 423 424 // FIXME: add __uuidof semantic analysis for type operand. 425 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 426 Operand, 427 SourceRange(TypeidLoc, RParenLoc))); 428} 429 430/// \brief Build a Microsoft __uuidof expression with an expression operand. 431ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 432 SourceLocation TypeidLoc, 433 Expr *E, 434 SourceLocation RParenLoc) { 435 if (!E->getType()->isDependentType()) { 436 if (!CXXUuidofExpr::GetUuidAttrOfType(E->getType()) && 437 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 438 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 439 } 440 // FIXME: add __uuidof semantic analysis for type operand. 441 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 442 E, 443 SourceRange(TypeidLoc, RParenLoc))); 444} 445 446/// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression); 447ExprResult 448Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc, 449 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 450 // If MSVCGuidDecl has not been cached, do the lookup. 451 if (!MSVCGuidDecl) { 452 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID"); 453 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName); 454 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 455 MSVCGuidDecl = R.getAsSingle<RecordDecl>(); 456 if (!MSVCGuidDecl) 457 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof)); 458 } 459 460 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl); 461 462 if (isType) { 463 // The operand is a type; handle it as such. 464 TypeSourceInfo *TInfo = 0; 465 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 466 &TInfo); 467 if (T.isNull()) 468 return ExprError(); 469 470 if (!TInfo) 471 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 472 473 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc); 474 } 475 476 // The operand is an expression. 477 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 478} 479 480/// ActOnCXXBoolLiteral - Parse {true,false} literals. 481ExprResult 482Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 483 assert((Kind == tok::kw_true || Kind == tok::kw_false) && 484 "Unknown C++ Boolean value!"); 485 return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true, 486 Context.BoolTy, OpLoc)); 487} 488 489/// ActOnCXXNullPtrLiteral - Parse 'nullptr'. 490ExprResult 491Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) { 492 return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc)); 493} 494 495/// ActOnCXXThrow - Parse throw expressions. 496ExprResult 497Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) { 498 bool IsThrownVarInScope = false; 499 if (Ex) { 500 // C++0x [class.copymove]p31: 501 // When certain criteria are met, an implementation is allowed to omit the 502 // copy/move construction of a class object [...] 503 // 504 // - in a throw-expression, when the operand is the name of a 505 // non-volatile automatic object (other than a function or catch- 506 // clause parameter) whose scope does not extend beyond the end of the 507 // innermost enclosing try-block (if there is one), the copy/move 508 // operation from the operand to the exception object (15.1) can be 509 // omitted by constructing the automatic object directly into the 510 // exception object 511 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens())) 512 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 513 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) { 514 for( ; S; S = S->getParent()) { 515 if (S->isDeclScope(Var)) { 516 IsThrownVarInScope = true; 517 break; 518 } 519 520 if (S->getFlags() & 521 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope | 522 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope | 523 Scope::TryScope)) 524 break; 525 } 526 } 527 } 528 } 529 530 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope); 531} 532 533ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex, 534 bool IsThrownVarInScope) { 535 // Don't report an error if 'throw' is used in system headers. 536 if (!getLangOpts().CXXExceptions && 537 !getSourceManager().isInSystemHeader(OpLoc)) 538 Diag(OpLoc, diag::err_exceptions_disabled) << "throw"; 539 540 if (Ex && !Ex->isTypeDependent()) { 541 ExprResult ExRes = CheckCXXThrowOperand(OpLoc, Ex, IsThrownVarInScope); 542 if (ExRes.isInvalid()) 543 return ExprError(); 544 Ex = ExRes.take(); 545 } 546 547 return Owned(new (Context) CXXThrowExpr(Ex, Context.VoidTy, OpLoc, 548 IsThrownVarInScope)); 549} 550 551/// CheckCXXThrowOperand - Validate the operand of a throw. 552ExprResult Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *E, 553 bool IsThrownVarInScope) { 554 // C++ [except.throw]p3: 555 // A throw-expression initializes a temporary object, called the exception 556 // object, the type of which is determined by removing any top-level 557 // cv-qualifiers from the static type of the operand of throw and adjusting 558 // the type from "array of T" or "function returning T" to "pointer to T" 559 // or "pointer to function returning T", [...] 560 if (E->getType().hasQualifiers()) 561 E = ImpCastExprToType(E, E->getType().getUnqualifiedType(), CK_NoOp, 562 E->getValueKind()).take(); 563 564 ExprResult Res = DefaultFunctionArrayConversion(E); 565 if (Res.isInvalid()) 566 return ExprError(); 567 E = Res.take(); 568 569 // If the type of the exception would be an incomplete type or a pointer 570 // to an incomplete type other than (cv) void the program is ill-formed. 571 QualType Ty = E->getType(); 572 bool isPointer = false; 573 if (const PointerType* Ptr = Ty->getAs<PointerType>()) { 574 Ty = Ptr->getPointeeType(); 575 isPointer = true; 576 } 577 if (!isPointer || !Ty->isVoidType()) { 578 if (RequireCompleteType(ThrowLoc, Ty, 579 isPointer? diag::err_throw_incomplete_ptr 580 : diag::err_throw_incomplete, 581 E->getSourceRange())) 582 return ExprError(); 583 584 if (RequireNonAbstractType(ThrowLoc, E->getType(), 585 diag::err_throw_abstract_type, E)) 586 return ExprError(); 587 } 588 589 // Initialize the exception result. This implicitly weeds out 590 // abstract types or types with inaccessible copy constructors. 591 592 // C++0x [class.copymove]p31: 593 // When certain criteria are met, an implementation is allowed to omit the 594 // copy/move construction of a class object [...] 595 // 596 // - in a throw-expression, when the operand is the name of a 597 // non-volatile automatic object (other than a function or catch-clause 598 // parameter) whose scope does not extend beyond the end of the 599 // innermost enclosing try-block (if there is one), the copy/move 600 // operation from the operand to the exception object (15.1) can be 601 // omitted by constructing the automatic object directly into the 602 // exception object 603 const VarDecl *NRVOVariable = 0; 604 if (IsThrownVarInScope) 605 NRVOVariable = getCopyElisionCandidate(QualType(), E, false); 606 607 InitializedEntity Entity = 608 InitializedEntity::InitializeException(ThrowLoc, E->getType(), 609 /*NRVO=*/NRVOVariable != 0); 610 Res = PerformMoveOrCopyInitialization(Entity, NRVOVariable, 611 QualType(), E, 612 IsThrownVarInScope); 613 if (Res.isInvalid()) 614 return ExprError(); 615 E = Res.take(); 616 617 // If the exception has class type, we need additional handling. 618 const RecordType *RecordTy = Ty->getAs<RecordType>(); 619 if (!RecordTy) 620 return Owned(E); 621 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl()); 622 623 // If we are throwing a polymorphic class type or pointer thereof, 624 // exception handling will make use of the vtable. 625 MarkVTableUsed(ThrowLoc, RD); 626 627 // If a pointer is thrown, the referenced object will not be destroyed. 628 if (isPointer) 629 return Owned(E); 630 631 // If the class has a destructor, we must be able to call it. 632 if (RD->hasIrrelevantDestructor()) 633 return Owned(E); 634 635 CXXDestructorDecl *Destructor = LookupDestructor(RD); 636 if (!Destructor) 637 return Owned(E); 638 639 MarkFunctionReferenced(E->getExprLoc(), Destructor); 640 CheckDestructorAccess(E->getExprLoc(), Destructor, 641 PDiag(diag::err_access_dtor_exception) << Ty); 642 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 643 return Owned(E); 644} 645 646QualType Sema::getCurrentThisType() { 647 DeclContext *DC = getFunctionLevelDeclContext(); 648 QualType ThisTy = CXXThisTypeOverride; 649 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) { 650 if (method && method->isInstance()) 651 ThisTy = method->getThisType(Context); 652 } 653 654 return ThisTy; 655} 656 657Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S, 658 Decl *ContextDecl, 659 unsigned CXXThisTypeQuals, 660 bool Enabled) 661 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false) 662{ 663 if (!Enabled || !ContextDecl) 664 return; 665 666 CXXRecordDecl *Record = 0; 667 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl)) 668 Record = Template->getTemplatedDecl(); 669 else 670 Record = cast<CXXRecordDecl>(ContextDecl); 671 672 S.CXXThisTypeOverride 673 = S.Context.getPointerType( 674 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals)); 675 676 this->Enabled = true; 677} 678 679 680Sema::CXXThisScopeRAII::~CXXThisScopeRAII() { 681 if (Enabled) { 682 S.CXXThisTypeOverride = OldCXXThisTypeOverride; 683 } 684} 685 686void Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit) { 687 // We don't need to capture this in an unevaluated context. 688 if (ExprEvalContexts.back().Context == Unevaluated && !Explicit) 689 return; 690 691 // Otherwise, check that we can capture 'this'. 692 unsigned NumClosures = 0; 693 for (unsigned idx = FunctionScopes.size() - 1; idx != 0; idx--) { 694 if (CapturingScopeInfo *CSI = 695 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) { 696 if (CSI->CXXThisCaptureIndex != 0) { 697 // 'this' is already being captured; there isn't anything more to do. 698 break; 699 } 700 701 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref || 702 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval || 703 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block || 704 Explicit) { 705 // This closure can capture 'this'; continue looking upwards. 706 NumClosures++; 707 Explicit = false; 708 continue; 709 } 710 // This context can't implicitly capture 'this'; fail out. 711 Diag(Loc, diag::err_this_capture) << Explicit; 712 return; 713 } 714 break; 715 } 716 717 // Mark that we're implicitly capturing 'this' in all the scopes we skipped. 718 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated 719 // contexts. 720 for (unsigned idx = FunctionScopes.size() - 1; 721 NumClosures; --idx, --NumClosures) { 722 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]); 723 Expr *ThisExpr = 0; 724 QualType ThisTy = getCurrentThisType(); 725 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) { 726 // For lambda expressions, build a field and an initializing expression. 727 CXXRecordDecl *Lambda = LSI->Lambda; 728 FieldDecl *Field 729 = FieldDecl::Create(Context, Lambda, Loc, Loc, 0, ThisTy, 730 Context.getTrivialTypeSourceInfo(ThisTy, Loc), 731 0, false, ICIS_NoInit); 732 Field->setImplicit(true); 733 Field->setAccess(AS_private); 734 Lambda->addDecl(Field); 735 ThisExpr = new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/true); 736 } 737 bool isNested = NumClosures > 1; 738 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr); 739 } 740} 741 742ExprResult Sema::ActOnCXXThis(SourceLocation Loc) { 743 /// C++ 9.3.2: In the body of a non-static member function, the keyword this 744 /// is a non-lvalue expression whose value is the address of the object for 745 /// which the function is called. 746 747 QualType ThisTy = getCurrentThisType(); 748 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use); 749 750 CheckCXXThisCapture(Loc); 751 return Owned(new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false)); 752} 753 754bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) { 755 // If we're outside the body of a member function, then we'll have a specified 756 // type for 'this'. 757 if (CXXThisTypeOverride.isNull()) 758 return false; 759 760 // Determine whether we're looking into a class that's currently being 761 // defined. 762 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl(); 763 return Class && Class->isBeingDefined(); 764} 765 766ExprResult 767Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep, 768 SourceLocation LParenLoc, 769 MultiExprArg exprs, 770 SourceLocation RParenLoc) { 771 if (!TypeRep) 772 return ExprError(); 773 774 TypeSourceInfo *TInfo; 775 QualType Ty = GetTypeFromParser(TypeRep, &TInfo); 776 if (!TInfo) 777 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation()); 778 779 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc); 780} 781 782/// ActOnCXXTypeConstructExpr - Parse construction of a specified type. 783/// Can be interpreted either as function-style casting ("int(x)") 784/// or class type construction ("ClassType(x,y,z)") 785/// or creation of a value-initialized type ("int()"). 786ExprResult 787Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, 788 SourceLocation LParenLoc, 789 MultiExprArg exprs, 790 SourceLocation RParenLoc) { 791 QualType Ty = TInfo->getType(); 792 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); 793 794 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(exprs)) { 795 return Owned(CXXUnresolvedConstructExpr::Create(Context, TInfo, 796 LParenLoc, 797 exprs, 798 RParenLoc)); 799 } 800 801 unsigned NumExprs = exprs.size(); 802 Expr **Exprs = exprs.data(); 803 804 bool ListInitialization = LParenLoc.isInvalid(); 805 assert((!ListInitialization || (NumExprs == 1 && isa<InitListExpr>(Exprs[0]))) 806 && "List initialization must have initializer list as expression."); 807 SourceRange FullRange = SourceRange(TyBeginLoc, 808 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc); 809 810 // C++ [expr.type.conv]p1: 811 // If the expression list is a single expression, the type conversion 812 // expression is equivalent (in definedness, and if defined in meaning) to the 813 // corresponding cast expression. 814 if (NumExprs == 1 && !ListInitialization) { 815 Expr *Arg = Exprs[0]; 816 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc); 817 } 818 819 QualType ElemTy = Ty; 820 if (Ty->isArrayType()) { 821 if (!ListInitialization) 822 return ExprError(Diag(TyBeginLoc, 823 diag::err_value_init_for_array_type) << FullRange); 824 ElemTy = Context.getBaseElementType(Ty); 825 } 826 827 if (!Ty->isVoidType() && 828 RequireCompleteType(TyBeginLoc, ElemTy, 829 diag::err_invalid_incomplete_type_use, FullRange)) 830 return ExprError(); 831 832 if (RequireNonAbstractType(TyBeginLoc, Ty, 833 diag::err_allocation_of_abstract_type)) 834 return ExprError(); 835 836 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo); 837 InitializationKind Kind 838 = NumExprs ? ListInitialization 839 ? InitializationKind::CreateDirectList(TyBeginLoc) 840 : InitializationKind::CreateDirect(TyBeginLoc, 841 LParenLoc, RParenLoc) 842 : InitializationKind::CreateValue(TyBeginLoc, 843 LParenLoc, RParenLoc); 844 InitializationSequence InitSeq(*this, Entity, Kind, Exprs, NumExprs); 845 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, exprs); 846 847 if (!Result.isInvalid() && ListInitialization && 848 isa<InitListExpr>(Result.get())) { 849 // If the list-initialization doesn't involve a constructor call, we'll get 850 // the initializer-list (with corrected type) back, but that's not what we 851 // want, since it will be treated as an initializer list in further 852 // processing. Explicitly insert a cast here. 853 InitListExpr *List = cast<InitListExpr>(Result.take()); 854 Result = Owned(CXXFunctionalCastExpr::Create(Context, List->getType(), 855 Expr::getValueKindForType(TInfo->getType()), 856 TInfo, TyBeginLoc, CK_NoOp, 857 List, /*Path=*/0, RParenLoc)); 858 } 859 860 // FIXME: Improve AST representation? 861 return Result; 862} 863 864/// doesUsualArrayDeleteWantSize - Answers whether the usual 865/// operator delete[] for the given type has a size_t parameter. 866static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc, 867 QualType allocType) { 868 const RecordType *record = 869 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>(); 870 if (!record) return false; 871 872 // Try to find an operator delete[] in class scope. 873 874 DeclarationName deleteName = 875 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete); 876 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName); 877 S.LookupQualifiedName(ops, record->getDecl()); 878 879 // We're just doing this for information. 880 ops.suppressDiagnostics(); 881 882 // Very likely: there's no operator delete[]. 883 if (ops.empty()) return false; 884 885 // If it's ambiguous, it should be illegal to call operator delete[] 886 // on this thing, so it doesn't matter if we allocate extra space or not. 887 if (ops.isAmbiguous()) return false; 888 889 LookupResult::Filter filter = ops.makeFilter(); 890 while (filter.hasNext()) { 891 NamedDecl *del = filter.next()->getUnderlyingDecl(); 892 893 // C++0x [basic.stc.dynamic.deallocation]p2: 894 // A template instance is never a usual deallocation function, 895 // regardless of its signature. 896 if (isa<FunctionTemplateDecl>(del)) { 897 filter.erase(); 898 continue; 899 } 900 901 // C++0x [basic.stc.dynamic.deallocation]p2: 902 // If class T does not declare [an operator delete[] with one 903 // parameter] but does declare a member deallocation function 904 // named operator delete[] with exactly two parameters, the 905 // second of which has type std::size_t, then this function 906 // is a usual deallocation function. 907 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) { 908 filter.erase(); 909 continue; 910 } 911 } 912 filter.done(); 913 914 if (!ops.isSingleResult()) return false; 915 916 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl()); 917 return (del->getNumParams() == 2); 918} 919 920/// \brief Parsed a C++ 'new' expression (C++ 5.3.4). 921/// 922/// E.g.: 923/// @code new (memory) int[size][4] @endcode 924/// or 925/// @code ::new Foo(23, "hello") @endcode 926/// 927/// \param StartLoc The first location of the expression. 928/// \param UseGlobal True if 'new' was prefixed with '::'. 929/// \param PlacementLParen Opening paren of the placement arguments. 930/// \param PlacementArgs Placement new arguments. 931/// \param PlacementRParen Closing paren of the placement arguments. 932/// \param TypeIdParens If the type is in parens, the source range. 933/// \param D The type to be allocated, as well as array dimensions. 934/// \param Initializer The initializing expression or initializer-list, or null 935/// if there is none. 936ExprResult 937Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal, 938 SourceLocation PlacementLParen, MultiExprArg PlacementArgs, 939 SourceLocation PlacementRParen, SourceRange TypeIdParens, 940 Declarator &D, Expr *Initializer) { 941 bool TypeContainsAuto = D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto; 942 943 Expr *ArraySize = 0; 944 // If the specified type is an array, unwrap it and save the expression. 945 if (D.getNumTypeObjects() > 0 && 946 D.getTypeObject(0).Kind == DeclaratorChunk::Array) { 947 DeclaratorChunk &Chunk = D.getTypeObject(0); 948 if (TypeContainsAuto) 949 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto) 950 << D.getSourceRange()); 951 if (Chunk.Arr.hasStatic) 952 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new) 953 << D.getSourceRange()); 954 if (!Chunk.Arr.NumElts) 955 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size) 956 << D.getSourceRange()); 957 958 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts); 959 D.DropFirstTypeObject(); 960 } 961 962 // Every dimension shall be of constant size. 963 if (ArraySize) { 964 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) { 965 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array) 966 break; 967 968 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr; 969 if (Expr *NumElts = (Expr *)Array.NumElts) { 970 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) { 971 Array.NumElts 972 = VerifyIntegerConstantExpression(NumElts, 0, 973 diag::err_new_array_nonconst) 974 .take(); 975 if (!Array.NumElts) 976 return ExprError(); 977 } 978 } 979 } 980 } 981 982 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/0); 983 QualType AllocType = TInfo->getType(); 984 if (D.isInvalidType()) 985 return ExprError(); 986 987 SourceRange DirectInitRange; 988 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) 989 DirectInitRange = List->getSourceRange(); 990 991 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal, 992 PlacementLParen, 993 PlacementArgs, 994 PlacementRParen, 995 TypeIdParens, 996 AllocType, 997 TInfo, 998 ArraySize, 999 DirectInitRange, 1000 Initializer, 1001 TypeContainsAuto); 1002} 1003 1004static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style, 1005 Expr *Init) { 1006 if (!Init) 1007 return true; 1008 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init)) 1009 return PLE->getNumExprs() == 0; 1010 if (isa<ImplicitValueInitExpr>(Init)) 1011 return true; 1012 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) 1013 return !CCE->isListInitialization() && 1014 CCE->getConstructor()->isDefaultConstructor(); 1015 else if (Style == CXXNewExpr::ListInit) { 1016 assert(isa<InitListExpr>(Init) && 1017 "Shouldn't create list CXXConstructExprs for arrays."); 1018 return true; 1019 } 1020 return false; 1021} 1022 1023ExprResult 1024Sema::BuildCXXNew(SourceRange Range, bool UseGlobal, 1025 SourceLocation PlacementLParen, 1026 MultiExprArg PlacementArgs, 1027 SourceLocation PlacementRParen, 1028 SourceRange TypeIdParens, 1029 QualType AllocType, 1030 TypeSourceInfo *AllocTypeInfo, 1031 Expr *ArraySize, 1032 SourceRange DirectInitRange, 1033 Expr *Initializer, 1034 bool TypeMayContainAuto) { 1035 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange(); 1036 SourceLocation StartLoc = Range.getBegin(); 1037 1038 CXXNewExpr::InitializationStyle initStyle; 1039 if (DirectInitRange.isValid()) { 1040 assert(Initializer && "Have parens but no initializer."); 1041 initStyle = CXXNewExpr::CallInit; 1042 } else if (Initializer && isa<InitListExpr>(Initializer)) 1043 initStyle = CXXNewExpr::ListInit; 1044 else { 1045 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) || 1046 isa<CXXConstructExpr>(Initializer)) && 1047 "Initializer expression that cannot have been implicitly created."); 1048 initStyle = CXXNewExpr::NoInit; 1049 } 1050 1051 Expr **Inits = &Initializer; 1052 unsigned NumInits = Initializer ? 1 : 0; 1053 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) { 1054 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init"); 1055 Inits = List->getExprs(); 1056 NumInits = List->getNumExprs(); 1057 } 1058 1059 // Determine whether we've already built the initializer. 1060 bool HaveCompleteInit = false; 1061 if (Initializer && isa<CXXConstructExpr>(Initializer) && 1062 !isa<CXXTemporaryObjectExpr>(Initializer)) 1063 HaveCompleteInit = true; 1064 else if (Initializer && isa<ImplicitValueInitExpr>(Initializer)) 1065 HaveCompleteInit = true; 1066 1067 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 1068 AutoType *AT = 0; 1069 if (TypeMayContainAuto && 1070 (AT = AllocType->getContainedAutoType()) && !AT->isDeduced()) { 1071 if (initStyle == CXXNewExpr::NoInit || NumInits == 0) 1072 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg) 1073 << AllocType << TypeRange); 1074 if (initStyle == CXXNewExpr::ListInit) 1075 return ExprError(Diag(Inits[0]->getLocStart(), 1076 diag::err_auto_new_requires_parens) 1077 << AllocType << TypeRange); 1078 if (NumInits > 1) { 1079 Expr *FirstBad = Inits[1]; 1080 return ExprError(Diag(FirstBad->getLocStart(), 1081 diag::err_auto_new_ctor_multiple_expressions) 1082 << AllocType << TypeRange); 1083 } 1084 Expr *Deduce = Inits[0]; 1085 TypeSourceInfo *DeducedType = 0; 1086 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed) 1087 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure) 1088 << AllocType << Deduce->getType() 1089 << TypeRange << Deduce->getSourceRange()); 1090 if (!DeducedType) 1091 return ExprError(); 1092 1093 AllocTypeInfo = DeducedType; 1094 AllocType = AllocTypeInfo->getType(); 1095 } 1096 1097 // Per C++0x [expr.new]p5, the type being constructed may be a 1098 // typedef of an array type. 1099 if (!ArraySize) { 1100 if (const ConstantArrayType *Array 1101 = Context.getAsConstantArrayType(AllocType)) { 1102 ArraySize = IntegerLiteral::Create(Context, Array->getSize(), 1103 Context.getSizeType(), 1104 TypeRange.getEnd()); 1105 AllocType = Array->getElementType(); 1106 } 1107 } 1108 1109 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange)) 1110 return ExprError(); 1111 1112 if (initStyle == CXXNewExpr::ListInit && isStdInitializerList(AllocType, 0)) { 1113 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(), 1114 diag::warn_dangling_std_initializer_list) 1115 << /*at end of FE*/0 << Inits[0]->getSourceRange(); 1116 } 1117 1118 // In ARC, infer 'retaining' for the allocated 1119 if (getLangOpts().ObjCAutoRefCount && 1120 AllocType.getObjCLifetime() == Qualifiers::OCL_None && 1121 AllocType->isObjCLifetimeType()) { 1122 AllocType = Context.getLifetimeQualifiedType(AllocType, 1123 AllocType->getObjCARCImplicitLifetime()); 1124 } 1125 1126 QualType ResultType = Context.getPointerType(AllocType); 1127 1128 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have 1129 // integral or enumeration type with a non-negative value." 1130 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped 1131 // enumeration type, or a class type for which a single non-explicit 1132 // conversion function to integral or unscoped enumeration type exists. 1133 if (ArraySize && !ArraySize->isTypeDependent()) { 1134 class SizeConvertDiagnoser : public ICEConvertDiagnoser { 1135 Expr *ArraySize; 1136 1137 public: 1138 SizeConvertDiagnoser(Expr *ArraySize) 1139 : ICEConvertDiagnoser(false, false), ArraySize(ArraySize) { } 1140 1141 virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc, 1142 QualType T) { 1143 return S.Diag(Loc, diag::err_array_size_not_integral) 1144 << S.getLangOpts().CPlusPlus11 << T; 1145 } 1146 1147 virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc, 1148 QualType T) { 1149 return S.Diag(Loc, diag::err_array_size_incomplete_type) 1150 << T << ArraySize->getSourceRange(); 1151 } 1152 1153 virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, 1154 SourceLocation Loc, 1155 QualType T, 1156 QualType ConvTy) { 1157 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy; 1158 } 1159 1160 virtual DiagnosticBuilder noteExplicitConv(Sema &S, 1161 CXXConversionDecl *Conv, 1162 QualType ConvTy) { 1163 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion) 1164 << ConvTy->isEnumeralType() << ConvTy; 1165 } 1166 1167 virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc, 1168 QualType T) { 1169 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T; 1170 } 1171 1172 virtual DiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv, 1173 QualType ConvTy) { 1174 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion) 1175 << ConvTy->isEnumeralType() << ConvTy; 1176 } 1177 1178 virtual DiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc, 1179 QualType T, 1180 QualType ConvTy) { 1181 return S.Diag(Loc, 1182 S.getLangOpts().CPlusPlus11 1183 ? diag::warn_cxx98_compat_array_size_conversion 1184 : diag::ext_array_size_conversion) 1185 << T << ConvTy->isEnumeralType() << ConvTy; 1186 } 1187 } SizeDiagnoser(ArraySize); 1188 1189 ExprResult ConvertedSize 1190 = ConvertToIntegralOrEnumerationType(StartLoc, ArraySize, SizeDiagnoser, 1191 /*AllowScopedEnumerations*/ false); 1192 if (ConvertedSize.isInvalid()) 1193 return ExprError(); 1194 1195 ArraySize = ConvertedSize.take(); 1196 QualType SizeType = ArraySize->getType(); 1197 if (!SizeType->isIntegralOrUnscopedEnumerationType()) 1198 return ExprError(); 1199 1200 // C++98 [expr.new]p7: 1201 // The expression in a direct-new-declarator shall have integral type 1202 // with a non-negative value. 1203 // 1204 // Let's see if this is a constant < 0. If so, we reject it out of 1205 // hand. Otherwise, if it's not a constant, we must have an unparenthesized 1206 // array type. 1207 // 1208 // Note: such a construct has well-defined semantics in C++11: it throws 1209 // std::bad_array_new_length. 1210 if (!ArraySize->isValueDependent()) { 1211 llvm::APSInt Value; 1212 // We've already performed any required implicit conversion to integer or 1213 // unscoped enumeration type. 1214 if (ArraySize->isIntegerConstantExpr(Value, Context)) { 1215 if (Value < llvm::APSInt( 1216 llvm::APInt::getNullValue(Value.getBitWidth()), 1217 Value.isUnsigned())) { 1218 if (getLangOpts().CPlusPlus11) 1219 Diag(ArraySize->getLocStart(), 1220 diag::warn_typecheck_negative_array_new_size) 1221 << ArraySize->getSourceRange(); 1222 else 1223 return ExprError(Diag(ArraySize->getLocStart(), 1224 diag::err_typecheck_negative_array_size) 1225 << ArraySize->getSourceRange()); 1226 } else if (!AllocType->isDependentType()) { 1227 unsigned ActiveSizeBits = 1228 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value); 1229 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 1230 if (getLangOpts().CPlusPlus11) 1231 Diag(ArraySize->getLocStart(), 1232 diag::warn_array_new_too_large) 1233 << Value.toString(10) 1234 << ArraySize->getSourceRange(); 1235 else 1236 return ExprError(Diag(ArraySize->getLocStart(), 1237 diag::err_array_too_large) 1238 << Value.toString(10) 1239 << ArraySize->getSourceRange()); 1240 } 1241 } 1242 } else if (TypeIdParens.isValid()) { 1243 // Can't have dynamic array size when the type-id is in parentheses. 1244 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst) 1245 << ArraySize->getSourceRange() 1246 << FixItHint::CreateRemoval(TypeIdParens.getBegin()) 1247 << FixItHint::CreateRemoval(TypeIdParens.getEnd()); 1248 1249 TypeIdParens = SourceRange(); 1250 } 1251 } 1252 1253 // Note that we do *not* convert the argument in any way. It can 1254 // be signed, larger than size_t, whatever. 1255 } 1256 1257 FunctionDecl *OperatorNew = 0; 1258 FunctionDecl *OperatorDelete = 0; 1259 Expr **PlaceArgs = PlacementArgs.data(); 1260 unsigned NumPlaceArgs = PlacementArgs.size(); 1261 1262 if (!AllocType->isDependentType() && 1263 !Expr::hasAnyTypeDependentArguments( 1264 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs)) && 1265 FindAllocationFunctions(StartLoc, 1266 SourceRange(PlacementLParen, PlacementRParen), 1267 UseGlobal, AllocType, ArraySize, PlaceArgs, 1268 NumPlaceArgs, OperatorNew, OperatorDelete)) 1269 return ExprError(); 1270 1271 // If this is an array allocation, compute whether the usual array 1272 // deallocation function for the type has a size_t parameter. 1273 bool UsualArrayDeleteWantsSize = false; 1274 if (ArraySize && !AllocType->isDependentType()) 1275 UsualArrayDeleteWantsSize 1276 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType); 1277 1278 SmallVector<Expr *, 8> AllPlaceArgs; 1279 if (OperatorNew) { 1280 // Add default arguments, if any. 1281 const FunctionProtoType *Proto = 1282 OperatorNew->getType()->getAs<FunctionProtoType>(); 1283 VariadicCallType CallType = 1284 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 1285 1286 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, 1287 Proto, 1, PlaceArgs, NumPlaceArgs, 1288 AllPlaceArgs, CallType)) 1289 return ExprError(); 1290 1291 NumPlaceArgs = AllPlaceArgs.size(); 1292 if (NumPlaceArgs > 0) 1293 PlaceArgs = &AllPlaceArgs[0]; 1294 1295 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, 1296 PlaceArgs, NumPlaceArgs); 1297 1298 // FIXME: Missing call to CheckFunctionCall or equivalent 1299 } 1300 1301 // Warn if the type is over-aligned and is being allocated by global operator 1302 // new. 1303 if (NumPlaceArgs == 0 && OperatorNew && 1304 (OperatorNew->isImplicit() || 1305 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1306 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1307 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1308 if (Align > SuitableAlign) 1309 Diag(StartLoc, diag::warn_overaligned_type) 1310 << AllocType 1311 << unsigned(Align / Context.getCharWidth()) 1312 << unsigned(SuitableAlign / Context.getCharWidth()); 1313 } 1314 } 1315 1316 QualType InitType = AllocType; 1317 // Array 'new' can't have any initializers except empty parentheses. 1318 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1319 // dialect distinction. 1320 if (ResultType->isArrayType() || ArraySize) { 1321 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1322 SourceRange InitRange(Inits[0]->getLocStart(), 1323 Inits[NumInits - 1]->getLocEnd()); 1324 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1325 return ExprError(); 1326 } 1327 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1328 // We do the initialization typechecking against the array type 1329 // corresponding to the number of initializers + 1 (to also check 1330 // default-initialization). 1331 unsigned NumElements = ILE->getNumInits() + 1; 1332 InitType = Context.getConstantArrayType(AllocType, 1333 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1334 ArrayType::Normal, 0); 1335 } 1336 } 1337 1338 // If we can perform the initialization, and we've not already done so, 1339 // do it now. 1340 if (!AllocType->isDependentType() && 1341 !Expr::hasAnyTypeDependentArguments( 1342 llvm::makeArrayRef(Inits, NumInits)) && 1343 !HaveCompleteInit) { 1344 // C++11 [expr.new]p15: 1345 // A new-expression that creates an object of type T initializes that 1346 // object as follows: 1347 InitializationKind Kind 1348 // - If the new-initializer is omitted, the object is default- 1349 // initialized (8.5); if no initialization is performed, 1350 // the object has indeterminate value 1351 = initStyle == CXXNewExpr::NoInit 1352 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1353 // - Otherwise, the new-initializer is interpreted according to the 1354 // initialization rules of 8.5 for direct-initialization. 1355 : initStyle == CXXNewExpr::ListInit 1356 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1357 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1358 DirectInitRange.getBegin(), 1359 DirectInitRange.getEnd()); 1360 1361 InitializedEntity Entity 1362 = InitializedEntity::InitializeNew(StartLoc, InitType); 1363 InitializationSequence InitSeq(*this, Entity, Kind, Inits, NumInits); 1364 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1365 MultiExprArg(Inits, NumInits)); 1366 if (FullInit.isInvalid()) 1367 return ExprError(); 1368 1369 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1370 // we don't want the initialized object to be destructed. 1371 if (CXXBindTemporaryExpr *Binder = 1372 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1373 FullInit = Owned(Binder->getSubExpr()); 1374 1375 Initializer = FullInit.take(); 1376 } 1377 1378 // Mark the new and delete operators as referenced. 1379 if (OperatorNew) 1380 MarkFunctionReferenced(StartLoc, OperatorNew); 1381 if (OperatorDelete) 1382 MarkFunctionReferenced(StartLoc, OperatorDelete); 1383 1384 // C++0x [expr.new]p17: 1385 // If the new expression creates an array of objects of class type, 1386 // access and ambiguity control are done for the destructor. 1387 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1388 if (ArraySize && !BaseAllocType->isDependentType()) { 1389 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) { 1390 if (CXXDestructorDecl *dtor = LookupDestructor( 1391 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) { 1392 MarkFunctionReferenced(StartLoc, dtor); 1393 CheckDestructorAccess(StartLoc, dtor, 1394 PDiag(diag::err_access_dtor) 1395 << BaseAllocType); 1396 DiagnoseUseOfDecl(dtor, StartLoc); 1397 } 1398 } 1399 } 1400 1401 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1402 OperatorDelete, 1403 UsualArrayDeleteWantsSize, 1404 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs), 1405 TypeIdParens, 1406 ArraySize, initStyle, Initializer, 1407 ResultType, AllocTypeInfo, 1408 Range, DirectInitRange)); 1409} 1410 1411/// \brief Checks that a type is suitable as the allocated type 1412/// in a new-expression. 1413bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1414 SourceRange R) { 1415 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1416 // abstract class type or array thereof. 1417 if (AllocType->isFunctionType()) 1418 return Diag(Loc, diag::err_bad_new_type) 1419 << AllocType << 0 << R; 1420 else if (AllocType->isReferenceType()) 1421 return Diag(Loc, diag::err_bad_new_type) 1422 << AllocType << 1 << R; 1423 else if (!AllocType->isDependentType() && 1424 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R)) 1425 return true; 1426 else if (RequireNonAbstractType(Loc, AllocType, 1427 diag::err_allocation_of_abstract_type)) 1428 return true; 1429 else if (AllocType->isVariablyModifiedType()) 1430 return Diag(Loc, diag::err_variably_modified_new_type) 1431 << AllocType; 1432 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1433 return Diag(Loc, diag::err_address_space_qualified_new) 1434 << AllocType.getUnqualifiedType() << AddressSpace; 1435 else if (getLangOpts().ObjCAutoRefCount) { 1436 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1437 QualType BaseAllocType = Context.getBaseElementType(AT); 1438 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1439 BaseAllocType->isObjCLifetimeType()) 1440 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1441 << BaseAllocType; 1442 } 1443 } 1444 1445 return false; 1446} 1447 1448/// \brief Determine whether the given function is a non-placement 1449/// deallocation function. 1450static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1451 if (FD->isInvalidDecl()) 1452 return false; 1453 1454 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1455 return Method->isUsualDeallocationFunction(); 1456 1457 return ((FD->getOverloadedOperator() == OO_Delete || 1458 FD->getOverloadedOperator() == OO_Array_Delete) && 1459 FD->getNumParams() == 1); 1460} 1461 1462/// FindAllocationFunctions - Finds the overloads of operator new and delete 1463/// that are appropriate for the allocation. 1464bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1465 bool UseGlobal, QualType AllocType, 1466 bool IsArray, Expr **PlaceArgs, 1467 unsigned NumPlaceArgs, 1468 FunctionDecl *&OperatorNew, 1469 FunctionDecl *&OperatorDelete) { 1470 // --- Choosing an allocation function --- 1471 // C++ 5.3.4p8 - 14 & 18 1472 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1473 // in the scope of the allocated class. 1474 // 2) If an array size is given, look for operator new[], else look for 1475 // operator new. 1476 // 3) The first argument is always size_t. Append the arguments from the 1477 // placement form. 1478 1479 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1480 // We don't care about the actual value of this argument. 1481 // FIXME: Should the Sema create the expression and embed it in the syntax 1482 // tree? Or should the consumer just recalculate the value? 1483 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1484 Context.getTargetInfo().getPointerWidth(0)), 1485 Context.getSizeType(), 1486 SourceLocation()); 1487 AllocArgs[0] = &Size; 1488 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1489 1490 // C++ [expr.new]p8: 1491 // If the allocated type is a non-array type, the allocation 1492 // function's name is operator new and the deallocation function's 1493 // name is operator delete. If the allocated type is an array 1494 // type, the allocation function's name is operator new[] and the 1495 // deallocation function's name is operator delete[]. 1496 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1497 IsArray ? OO_Array_New : OO_New); 1498 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1499 IsArray ? OO_Array_Delete : OO_Delete); 1500 1501 QualType AllocElemType = Context.getBaseElementType(AllocType); 1502 1503 if (AllocElemType->isRecordType() && !UseGlobal) { 1504 CXXRecordDecl *Record 1505 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1506 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1507 AllocArgs.size(), Record, /*AllowMissing=*/true, 1508 OperatorNew)) 1509 return true; 1510 } 1511 if (!OperatorNew) { 1512 // Didn't find a member overload. Look for a global one. 1513 DeclareGlobalNewDelete(); 1514 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1515 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1516 AllocArgs.size(), TUDecl, /*AllowMissing=*/false, 1517 OperatorNew)) 1518 return true; 1519 } 1520 1521 // We don't need an operator delete if we're running under 1522 // -fno-exceptions. 1523 if (!getLangOpts().Exceptions) { 1524 OperatorDelete = 0; 1525 return false; 1526 } 1527 1528 // FindAllocationOverload can change the passed in arguments, so we need to 1529 // copy them back. 1530 if (NumPlaceArgs > 0) 1531 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1532 1533 // C++ [expr.new]p19: 1534 // 1535 // If the new-expression begins with a unary :: operator, the 1536 // deallocation function's name is looked up in the global 1537 // scope. Otherwise, if the allocated type is a class type T or an 1538 // array thereof, the deallocation function's name is looked up in 1539 // the scope of T. If this lookup fails to find the name, or if 1540 // the allocated type is not a class type or array thereof, the 1541 // deallocation function's name is looked up in the global scope. 1542 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1543 if (AllocElemType->isRecordType() && !UseGlobal) { 1544 CXXRecordDecl *RD 1545 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1546 LookupQualifiedName(FoundDelete, RD); 1547 } 1548 if (FoundDelete.isAmbiguous()) 1549 return true; // FIXME: clean up expressions? 1550 1551 if (FoundDelete.empty()) { 1552 DeclareGlobalNewDelete(); 1553 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1554 } 1555 1556 FoundDelete.suppressDiagnostics(); 1557 1558 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1559 1560 // Whether we're looking for a placement operator delete is dictated 1561 // by whether we selected a placement operator new, not by whether 1562 // we had explicit placement arguments. This matters for things like 1563 // struct A { void *operator new(size_t, int = 0); ... }; 1564 // A *a = new A() 1565 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1566 1567 if (isPlacementNew) { 1568 // C++ [expr.new]p20: 1569 // A declaration of a placement deallocation function matches the 1570 // declaration of a placement allocation function if it has the 1571 // same number of parameters and, after parameter transformations 1572 // (8.3.5), all parameter types except the first are 1573 // identical. [...] 1574 // 1575 // To perform this comparison, we compute the function type that 1576 // the deallocation function should have, and use that type both 1577 // for template argument deduction and for comparison purposes. 1578 // 1579 // FIXME: this comparison should ignore CC and the like. 1580 QualType ExpectedFunctionType; 1581 { 1582 const FunctionProtoType *Proto 1583 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1584 1585 SmallVector<QualType, 4> ArgTypes; 1586 ArgTypes.push_back(Context.VoidPtrTy); 1587 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1588 ArgTypes.push_back(Proto->getArgType(I)); 1589 1590 FunctionProtoType::ExtProtoInfo EPI; 1591 EPI.Variadic = Proto->isVariadic(); 1592 1593 ExpectedFunctionType 1594 = Context.getFunctionType(Context.VoidTy, ArgTypes.data(), 1595 ArgTypes.size(), EPI); 1596 } 1597 1598 for (LookupResult::iterator D = FoundDelete.begin(), 1599 DEnd = FoundDelete.end(); 1600 D != DEnd; ++D) { 1601 FunctionDecl *Fn = 0; 1602 if (FunctionTemplateDecl *FnTmpl 1603 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1604 // Perform template argument deduction to try to match the 1605 // expected function type. 1606 TemplateDeductionInfo Info(StartLoc); 1607 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1608 continue; 1609 } else 1610 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1611 1612 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1613 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1614 } 1615 } else { 1616 // C++ [expr.new]p20: 1617 // [...] Any non-placement deallocation function matches a 1618 // non-placement allocation function. [...] 1619 for (LookupResult::iterator D = FoundDelete.begin(), 1620 DEnd = FoundDelete.end(); 1621 D != DEnd; ++D) { 1622 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1623 if (isNonPlacementDeallocationFunction(Fn)) 1624 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1625 } 1626 } 1627 1628 // C++ [expr.new]p20: 1629 // [...] If the lookup finds a single matching deallocation 1630 // function, that function will be called; otherwise, no 1631 // deallocation function will be called. 1632 if (Matches.size() == 1) { 1633 OperatorDelete = Matches[0].second; 1634 1635 // C++0x [expr.new]p20: 1636 // If the lookup finds the two-parameter form of a usual 1637 // deallocation function (3.7.4.2) and that function, considered 1638 // as a placement deallocation function, would have been 1639 // selected as a match for the allocation function, the program 1640 // is ill-formed. 1641 if (NumPlaceArgs && getLangOpts().CPlusPlus11 && 1642 isNonPlacementDeallocationFunction(OperatorDelete)) { 1643 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1644 << SourceRange(PlaceArgs[0]->getLocStart(), 1645 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1646 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1647 << DeleteName; 1648 } else { 1649 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1650 Matches[0].first); 1651 } 1652 } 1653 1654 return false; 1655} 1656 1657/// FindAllocationOverload - Find an fitting overload for the allocation 1658/// function in the specified scope. 1659bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1660 DeclarationName Name, Expr** Args, 1661 unsigned NumArgs, DeclContext *Ctx, 1662 bool AllowMissing, FunctionDecl *&Operator, 1663 bool Diagnose) { 1664 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1665 LookupQualifiedName(R, Ctx); 1666 if (R.empty()) { 1667 if (AllowMissing || !Diagnose) 1668 return false; 1669 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1670 << Name << Range; 1671 } 1672 1673 if (R.isAmbiguous()) 1674 return true; 1675 1676 R.suppressDiagnostics(); 1677 1678 OverloadCandidateSet Candidates(StartLoc); 1679 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1680 Alloc != AllocEnd; ++Alloc) { 1681 // Even member operator new/delete are implicitly treated as 1682 // static, so don't use AddMemberCandidate. 1683 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1684 1685 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1686 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1687 /*ExplicitTemplateArgs=*/0, 1688 llvm::makeArrayRef(Args, NumArgs), 1689 Candidates, 1690 /*SuppressUserConversions=*/false); 1691 continue; 1692 } 1693 1694 FunctionDecl *Fn = cast<FunctionDecl>(D); 1695 AddOverloadCandidate(Fn, Alloc.getPair(), 1696 llvm::makeArrayRef(Args, NumArgs), Candidates, 1697 /*SuppressUserConversions=*/false); 1698 } 1699 1700 // Do the resolution. 1701 OverloadCandidateSet::iterator Best; 1702 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1703 case OR_Success: { 1704 // Got one! 1705 FunctionDecl *FnDecl = Best->Function; 1706 MarkFunctionReferenced(StartLoc, FnDecl); 1707 // The first argument is size_t, and the first parameter must be size_t, 1708 // too. This is checked on declaration and can be assumed. (It can't be 1709 // asserted on, though, since invalid decls are left in there.) 1710 // Watch out for variadic allocator function. 1711 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1712 for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) { 1713 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1714 FnDecl->getParamDecl(i)); 1715 1716 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1717 return true; 1718 1719 ExprResult Result 1720 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1721 if (Result.isInvalid()) 1722 return true; 1723 1724 Args[i] = Result.takeAs<Expr>(); 1725 } 1726 1727 Operator = FnDecl; 1728 1729 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), 1730 Best->FoundDecl, Diagnose) == AR_inaccessible) 1731 return true; 1732 1733 return false; 1734 } 1735 1736 case OR_No_Viable_Function: 1737 if (Diagnose) { 1738 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1739 << Name << Range; 1740 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1741 llvm::makeArrayRef(Args, NumArgs)); 1742 } 1743 return true; 1744 1745 case OR_Ambiguous: 1746 if (Diagnose) { 1747 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1748 << Name << Range; 1749 Candidates.NoteCandidates(*this, OCD_ViableCandidates, 1750 llvm::makeArrayRef(Args, NumArgs)); 1751 } 1752 return true; 1753 1754 case OR_Deleted: { 1755 if (Diagnose) { 1756 Diag(StartLoc, diag::err_ovl_deleted_call) 1757 << Best->Function->isDeleted() 1758 << Name 1759 << getDeletedOrUnavailableSuffix(Best->Function) 1760 << Range; 1761 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1762 llvm::makeArrayRef(Args, NumArgs)); 1763 } 1764 return true; 1765 } 1766 } 1767 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1768} 1769 1770 1771/// DeclareGlobalNewDelete - Declare the global forms of operator new and 1772/// delete. These are: 1773/// @code 1774/// // C++03: 1775/// void* operator new(std::size_t) throw(std::bad_alloc); 1776/// void* operator new[](std::size_t) throw(std::bad_alloc); 1777/// void operator delete(void *) throw(); 1778/// void operator delete[](void *) throw(); 1779/// // C++0x: 1780/// void* operator new(std::size_t); 1781/// void* operator new[](std::size_t); 1782/// void operator delete(void *); 1783/// void operator delete[](void *); 1784/// @endcode 1785/// C++0x operator delete is implicitly noexcept. 1786/// Note that the placement and nothrow forms of new are *not* implicitly 1787/// declared. Their use requires including \<new\>. 1788void Sema::DeclareGlobalNewDelete() { 1789 if (GlobalNewDeleteDeclared) 1790 return; 1791 1792 // C++ [basic.std.dynamic]p2: 1793 // [...] The following allocation and deallocation functions (18.4) are 1794 // implicitly declared in global scope in each translation unit of a 1795 // program 1796 // 1797 // C++03: 1798 // void* operator new(std::size_t) throw(std::bad_alloc); 1799 // void* operator new[](std::size_t) throw(std::bad_alloc); 1800 // void operator delete(void*) throw(); 1801 // void operator delete[](void*) throw(); 1802 // C++0x: 1803 // void* operator new(std::size_t); 1804 // void* operator new[](std::size_t); 1805 // void operator delete(void*); 1806 // void operator delete[](void*); 1807 // 1808 // These implicit declarations introduce only the function names operator 1809 // new, operator new[], operator delete, operator delete[]. 1810 // 1811 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1812 // "std" or "bad_alloc" as necessary to form the exception specification. 1813 // However, we do not make these implicit declarations visible to name 1814 // lookup. 1815 // Note that the C++0x versions of operator delete are deallocation functions, 1816 // and thus are implicitly noexcept. 1817 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) { 1818 // The "std::bad_alloc" class has not yet been declared, so build it 1819 // implicitly. 1820 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1821 getOrCreateStdNamespace(), 1822 SourceLocation(), SourceLocation(), 1823 &PP.getIdentifierTable().get("bad_alloc"), 1824 0); 1825 getStdBadAlloc()->setImplicit(true); 1826 } 1827 1828 GlobalNewDeleteDeclared = true; 1829 1830 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1831 QualType SizeT = Context.getSizeType(); 1832 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew; 1833 1834 DeclareGlobalAllocationFunction( 1835 Context.DeclarationNames.getCXXOperatorName(OO_New), 1836 VoidPtr, SizeT, AssumeSaneOperatorNew); 1837 DeclareGlobalAllocationFunction( 1838 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1839 VoidPtr, SizeT, AssumeSaneOperatorNew); 1840 DeclareGlobalAllocationFunction( 1841 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1842 Context.VoidTy, VoidPtr); 1843 DeclareGlobalAllocationFunction( 1844 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1845 Context.VoidTy, VoidPtr); 1846} 1847 1848/// DeclareGlobalAllocationFunction - Declares a single implicit global 1849/// allocation function if it doesn't already exist. 1850void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1851 QualType Return, QualType Argument, 1852 bool AddMallocAttr) { 1853 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1854 1855 // Check if this function is already declared. 1856 { 1857 DeclContext::lookup_result R = GlobalCtx->lookup(Name); 1858 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end(); 1859 Alloc != AllocEnd; ++Alloc) { 1860 // Only look at non-template functions, as it is the predefined, 1861 // non-templated allocation function we are trying to declare here. 1862 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1863 QualType InitialParamType = 1864 Context.getCanonicalType( 1865 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1866 // FIXME: Do we need to check for default arguments here? 1867 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1868 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1869 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1870 return; 1871 } 1872 } 1873 } 1874 } 1875 1876 QualType BadAllocType; 1877 bool HasBadAllocExceptionSpec 1878 = (Name.getCXXOverloadedOperator() == OO_New || 1879 Name.getCXXOverloadedOperator() == OO_Array_New); 1880 if (HasBadAllocExceptionSpec && !getLangOpts().CPlusPlus11) { 1881 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1882 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1883 } 1884 1885 FunctionProtoType::ExtProtoInfo EPI; 1886 if (HasBadAllocExceptionSpec) { 1887 if (!getLangOpts().CPlusPlus11) { 1888 EPI.ExceptionSpecType = EST_Dynamic; 1889 EPI.NumExceptions = 1; 1890 EPI.Exceptions = &BadAllocType; 1891 } 1892 } else { 1893 EPI.ExceptionSpecType = getLangOpts().CPlusPlus11 ? 1894 EST_BasicNoexcept : EST_DynamicNone; 1895 } 1896 1897 QualType FnType = Context.getFunctionType(Return, &Argument, 1, EPI); 1898 FunctionDecl *Alloc = 1899 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1900 SourceLocation(), Name, 1901 FnType, /*TInfo=*/0, SC_None, 1902 SC_None, false, true); 1903 Alloc->setImplicit(); 1904 1905 if (AddMallocAttr) 1906 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1907 1908 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1909 SourceLocation(), 0, 1910 Argument, /*TInfo=*/0, 1911 SC_None, SC_None, 0); 1912 Alloc->setParams(Param); 1913 1914 // FIXME: Also add this declaration to the IdentifierResolver, but 1915 // make sure it is at the end of the chain to coincide with the 1916 // global scope. 1917 Context.getTranslationUnitDecl()->addDecl(Alloc); 1918} 1919 1920bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1921 DeclarationName Name, 1922 FunctionDecl* &Operator, bool Diagnose) { 1923 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1924 // Try to find operator delete/operator delete[] in class scope. 1925 LookupQualifiedName(Found, RD); 1926 1927 if (Found.isAmbiguous()) 1928 return true; 1929 1930 Found.suppressDiagnostics(); 1931 1932 SmallVector<DeclAccessPair,4> Matches; 1933 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1934 F != FEnd; ++F) { 1935 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1936 1937 // Ignore template operator delete members from the check for a usual 1938 // deallocation function. 1939 if (isa<FunctionTemplateDecl>(ND)) 1940 continue; 1941 1942 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1943 Matches.push_back(F.getPair()); 1944 } 1945 1946 // There's exactly one suitable operator; pick it. 1947 if (Matches.size() == 1) { 1948 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 1949 1950 if (Operator->isDeleted()) { 1951 if (Diagnose) { 1952 Diag(StartLoc, diag::err_deleted_function_use); 1953 NoteDeletedFunction(Operator); 1954 } 1955 return true; 1956 } 1957 1958 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 1959 Matches[0], Diagnose) == AR_inaccessible) 1960 return true; 1961 1962 return false; 1963 1964 // We found multiple suitable operators; complain about the ambiguity. 1965 } else if (!Matches.empty()) { 1966 if (Diagnose) { 1967 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 1968 << Name << RD; 1969 1970 for (SmallVectorImpl<DeclAccessPair>::iterator 1971 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 1972 Diag((*F)->getUnderlyingDecl()->getLocation(), 1973 diag::note_member_declared_here) << Name; 1974 } 1975 return true; 1976 } 1977 1978 // We did find operator delete/operator delete[] declarations, but 1979 // none of them were suitable. 1980 if (!Found.empty()) { 1981 if (Diagnose) { 1982 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 1983 << Name << RD; 1984 1985 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1986 F != FEnd; ++F) 1987 Diag((*F)->getUnderlyingDecl()->getLocation(), 1988 diag::note_member_declared_here) << Name; 1989 } 1990 return true; 1991 } 1992 1993 // Look for a global declaration. 1994 DeclareGlobalNewDelete(); 1995 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1996 1997 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 1998 Expr* DeallocArgs[1]; 1999 DeallocArgs[0] = &Null; 2000 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 2001 DeallocArgs, 1, TUDecl, !Diagnose, 2002 Operator, Diagnose)) 2003 return true; 2004 2005 assert(Operator && "Did not find a deallocation function!"); 2006 return false; 2007} 2008 2009/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 2010/// @code ::delete ptr; @endcode 2011/// or 2012/// @code delete [] ptr; @endcode 2013ExprResult 2014Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 2015 bool ArrayForm, Expr *ExE) { 2016 // C++ [expr.delete]p1: 2017 // The operand shall have a pointer type, or a class type having a single 2018 // conversion function to a pointer type. The result has type void. 2019 // 2020 // DR599 amends "pointer type" to "pointer to object type" in both cases. 2021 2022 ExprResult Ex = Owned(ExE); 2023 FunctionDecl *OperatorDelete = 0; 2024 bool ArrayFormAsWritten = ArrayForm; 2025 bool UsualArrayDeleteWantsSize = false; 2026 2027 if (!Ex.get()->isTypeDependent()) { 2028 // Perform lvalue-to-rvalue cast, if needed. 2029 Ex = DefaultLvalueConversion(Ex.take()); 2030 if (Ex.isInvalid()) 2031 return ExprError(); 2032 2033 QualType Type = Ex.get()->getType(); 2034 2035 if (const RecordType *Record = Type->getAs<RecordType>()) { 2036 if (RequireCompleteType(StartLoc, Type, 2037 diag::err_delete_incomplete_class_type)) 2038 return ExprError(); 2039 2040 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 2041 2042 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 2043 std::pair<CXXRecordDecl::conversion_iterator, 2044 CXXRecordDecl::conversion_iterator> 2045 Conversions = RD->getVisibleConversionFunctions(); 2046 for (CXXRecordDecl::conversion_iterator 2047 I = Conversions.first, E = Conversions.second; I != E; ++I) { 2048 NamedDecl *D = I.getDecl(); 2049 if (isa<UsingShadowDecl>(D)) 2050 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2051 2052 // Skip over templated conversion functions; they aren't considered. 2053 if (isa<FunctionTemplateDecl>(D)) 2054 continue; 2055 2056 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 2057 2058 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 2059 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 2060 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 2061 ObjectPtrConversions.push_back(Conv); 2062 } 2063 if (ObjectPtrConversions.size() == 1) { 2064 // We have a single conversion to a pointer-to-object type. Perform 2065 // that conversion. 2066 // TODO: don't redo the conversion calculation. 2067 ExprResult Res = 2068 PerformImplicitConversion(Ex.get(), 2069 ObjectPtrConversions.front()->getConversionType(), 2070 AA_Converting); 2071 if (Res.isUsable()) { 2072 Ex = Res; 2073 Type = Ex.get()->getType(); 2074 } 2075 } 2076 else if (ObjectPtrConversions.size() > 1) { 2077 Diag(StartLoc, diag::err_ambiguous_delete_operand) 2078 << Type << Ex.get()->getSourceRange(); 2079 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 2080 NoteOverloadCandidate(ObjectPtrConversions[i]); 2081 return ExprError(); 2082 } 2083 } 2084 2085 if (!Type->isPointerType()) 2086 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2087 << Type << Ex.get()->getSourceRange()); 2088 2089 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2090 QualType PointeeElem = Context.getBaseElementType(Pointee); 2091 2092 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2093 return Diag(Ex.get()->getLocStart(), 2094 diag::err_address_space_qualified_delete) 2095 << Pointee.getUnqualifiedType() << AddressSpace; 2096 2097 CXXRecordDecl *PointeeRD = 0; 2098 if (Pointee->isVoidType() && !isSFINAEContext()) { 2099 // The C++ standard bans deleting a pointer to a non-object type, which 2100 // effectively bans deletion of "void*". However, most compilers support 2101 // this, so we treat it as a warning unless we're in a SFINAE context. 2102 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2103 << Type << Ex.get()->getSourceRange(); 2104 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2105 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2106 << Type << Ex.get()->getSourceRange()); 2107 } else if (!Pointee->isDependentType()) { 2108 if (!RequireCompleteType(StartLoc, Pointee, 2109 diag::warn_delete_incomplete, Ex.get())) { 2110 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2111 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2112 } 2113 } 2114 2115 // C++ [expr.delete]p2: 2116 // [Note: a pointer to a const type can be the operand of a 2117 // delete-expression; it is not necessary to cast away the constness 2118 // (5.2.11) of the pointer expression before it is used as the operand 2119 // of the delete-expression. ] 2120 2121 if (Pointee->isArrayType() && !ArrayForm) { 2122 Diag(StartLoc, diag::warn_delete_array_type) 2123 << Type << Ex.get()->getSourceRange() 2124 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2125 ArrayForm = true; 2126 } 2127 2128 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2129 ArrayForm ? OO_Array_Delete : OO_Delete); 2130 2131 if (PointeeRD) { 2132 if (!UseGlobal && 2133 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2134 OperatorDelete)) 2135 return ExprError(); 2136 2137 // If we're allocating an array of records, check whether the 2138 // usual operator delete[] has a size_t parameter. 2139 if (ArrayForm) { 2140 // If the user specifically asked to use the global allocator, 2141 // we'll need to do the lookup into the class. 2142 if (UseGlobal) 2143 UsualArrayDeleteWantsSize = 2144 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2145 2146 // Otherwise, the usual operator delete[] should be the 2147 // function we just found. 2148 else if (isa<CXXMethodDecl>(OperatorDelete)) 2149 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2150 } 2151 2152 if (!PointeeRD->hasIrrelevantDestructor()) 2153 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2154 MarkFunctionReferenced(StartLoc, 2155 const_cast<CXXDestructorDecl*>(Dtor)); 2156 DiagnoseUseOfDecl(Dtor, StartLoc); 2157 } 2158 2159 // C++ [expr.delete]p3: 2160 // In the first alternative (delete object), if the static type of the 2161 // object to be deleted is different from its dynamic type, the static 2162 // type shall be a base class of the dynamic type of the object to be 2163 // deleted and the static type shall have a virtual destructor or the 2164 // behavior is undefined. 2165 // 2166 // Note: a final class cannot be derived from, no issue there 2167 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2168 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2169 if (dtor && !dtor->isVirtual()) { 2170 if (PointeeRD->isAbstract()) { 2171 // If the class is abstract, we warn by default, because we're 2172 // sure the code has undefined behavior. 2173 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2174 << PointeeElem; 2175 } else if (!ArrayForm) { 2176 // Otherwise, if this is not an array delete, it's a bit suspect, 2177 // but not necessarily wrong. 2178 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2179 } 2180 } 2181 } 2182 2183 } 2184 2185 if (!OperatorDelete) { 2186 // Look for a global declaration. 2187 DeclareGlobalNewDelete(); 2188 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2189 Expr *Arg = Ex.get(); 2190 if (!Context.hasSameType(Arg->getType(), Context.VoidPtrTy)) 2191 Arg = ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2192 CK_BitCast, Arg, 0, VK_RValue); 2193 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2194 &Arg, 1, TUDecl, /*AllowMissing=*/false, 2195 OperatorDelete)) 2196 return ExprError(); 2197 } 2198 2199 MarkFunctionReferenced(StartLoc, OperatorDelete); 2200 2201 // Check access and ambiguity of operator delete and destructor. 2202 if (PointeeRD) { 2203 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2204 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2205 PDiag(diag::err_access_dtor) << PointeeElem); 2206 } 2207 } 2208 2209 } 2210 2211 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2212 ArrayFormAsWritten, 2213 UsualArrayDeleteWantsSize, 2214 OperatorDelete, Ex.take(), StartLoc)); 2215} 2216 2217/// \brief Check the use of the given variable as a C++ condition in an if, 2218/// while, do-while, or switch statement. 2219ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2220 SourceLocation StmtLoc, 2221 bool ConvertToBoolean) { 2222 QualType T = ConditionVar->getType(); 2223 2224 // C++ [stmt.select]p2: 2225 // The declarator shall not specify a function or an array. 2226 if (T->isFunctionType()) 2227 return ExprError(Diag(ConditionVar->getLocation(), 2228 diag::err_invalid_use_of_function_type) 2229 << ConditionVar->getSourceRange()); 2230 else if (T->isArrayType()) 2231 return ExprError(Diag(ConditionVar->getLocation(), 2232 diag::err_invalid_use_of_array_type) 2233 << ConditionVar->getSourceRange()); 2234 2235 ExprResult Condition = 2236 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2237 SourceLocation(), 2238 ConditionVar, 2239 /*enclosing*/ false, 2240 ConditionVar->getLocation(), 2241 ConditionVar->getType().getNonReferenceType(), 2242 VK_LValue)); 2243 2244 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2245 2246 if (ConvertToBoolean) { 2247 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2248 if (Condition.isInvalid()) 2249 return ExprError(); 2250 } 2251 2252 return Condition; 2253} 2254 2255/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2256ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2257 // C++ 6.4p4: 2258 // The value of a condition that is an initialized declaration in a statement 2259 // other than a switch statement is the value of the declared variable 2260 // implicitly converted to type bool. If that conversion is ill-formed, the 2261 // program is ill-formed. 2262 // The value of a condition that is an expression is the value of the 2263 // expression, implicitly converted to bool. 2264 // 2265 return PerformContextuallyConvertToBool(CondExpr); 2266} 2267 2268/// Helper function to determine whether this is the (deprecated) C++ 2269/// conversion from a string literal to a pointer to non-const char or 2270/// non-const wchar_t (for narrow and wide string literals, 2271/// respectively). 2272bool 2273Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2274 // Look inside the implicit cast, if it exists. 2275 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2276 From = Cast->getSubExpr(); 2277 2278 // A string literal (2.13.4) that is not a wide string literal can 2279 // be converted to an rvalue of type "pointer to char"; a wide 2280 // string literal can be converted to an rvalue of type "pointer 2281 // to wchar_t" (C++ 4.2p2). 2282 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2283 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2284 if (const BuiltinType *ToPointeeType 2285 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2286 // This conversion is considered only when there is an 2287 // explicit appropriate pointer target type (C++ 4.2p2). 2288 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2289 switch (StrLit->getKind()) { 2290 case StringLiteral::UTF8: 2291 case StringLiteral::UTF16: 2292 case StringLiteral::UTF32: 2293 // We don't allow UTF literals to be implicitly converted 2294 break; 2295 case StringLiteral::Ascii: 2296 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2297 ToPointeeType->getKind() == BuiltinType::Char_S); 2298 case StringLiteral::Wide: 2299 return ToPointeeType->isWideCharType(); 2300 } 2301 } 2302 } 2303 2304 return false; 2305} 2306 2307static ExprResult BuildCXXCastArgument(Sema &S, 2308 SourceLocation CastLoc, 2309 QualType Ty, 2310 CastKind Kind, 2311 CXXMethodDecl *Method, 2312 DeclAccessPair FoundDecl, 2313 bool HadMultipleCandidates, 2314 Expr *From) { 2315 switch (Kind) { 2316 default: llvm_unreachable("Unhandled cast kind!"); 2317 case CK_ConstructorConversion: { 2318 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2319 SmallVector<Expr*, 8> ConstructorArgs; 2320 2321 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs)) 2322 return ExprError(); 2323 2324 S.CheckConstructorAccess(CastLoc, Constructor, 2325 InitializedEntity::InitializeTemporary(Ty), 2326 Constructor->getAccess()); 2327 2328 ExprResult Result 2329 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2330 ConstructorArgs, HadMultipleCandidates, 2331 /*ListInit*/ false, /*ZeroInit*/ false, 2332 CXXConstructExpr::CK_Complete, SourceRange()); 2333 if (Result.isInvalid()) 2334 return ExprError(); 2335 2336 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2337 } 2338 2339 case CK_UserDefinedConversion: { 2340 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2341 2342 // Create an implicit call expr that calls it. 2343 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method); 2344 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv, 2345 HadMultipleCandidates); 2346 if (Result.isInvalid()) 2347 return ExprError(); 2348 // Record usage of conversion in an implicit cast. 2349 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2350 Result.get()->getType(), 2351 CK_UserDefinedConversion, 2352 Result.get(), 0, 2353 Result.get()->getValueKind())); 2354 2355 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2356 2357 return S.MaybeBindToTemporary(Result.get()); 2358 } 2359 } 2360} 2361 2362/// PerformImplicitConversion - Perform an implicit conversion of the 2363/// expression From to the type ToType using the pre-computed implicit 2364/// conversion sequence ICS. Returns the converted 2365/// expression. Action is the kind of conversion we're performing, 2366/// used in the error message. 2367ExprResult 2368Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2369 const ImplicitConversionSequence &ICS, 2370 AssignmentAction Action, 2371 CheckedConversionKind CCK) { 2372 switch (ICS.getKind()) { 2373 case ImplicitConversionSequence::StandardConversion: { 2374 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2375 Action, CCK); 2376 if (Res.isInvalid()) 2377 return ExprError(); 2378 From = Res.take(); 2379 break; 2380 } 2381 2382 case ImplicitConversionSequence::UserDefinedConversion: { 2383 2384 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2385 CastKind CastKind; 2386 QualType BeforeToType; 2387 assert(FD && "FIXME: aggregate initialization from init list"); 2388 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2389 CastKind = CK_UserDefinedConversion; 2390 2391 // If the user-defined conversion is specified by a conversion function, 2392 // the initial standard conversion sequence converts the source type to 2393 // the implicit object parameter of the conversion function. 2394 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2395 } else { 2396 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2397 CastKind = CK_ConstructorConversion; 2398 // Do no conversion if dealing with ... for the first conversion. 2399 if (!ICS.UserDefined.EllipsisConversion) { 2400 // If the user-defined conversion is specified by a constructor, the 2401 // initial standard conversion sequence converts the source type to the 2402 // type required by the argument of the constructor 2403 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2404 } 2405 } 2406 // Watch out for elipsis conversion. 2407 if (!ICS.UserDefined.EllipsisConversion) { 2408 ExprResult Res = 2409 PerformImplicitConversion(From, BeforeToType, 2410 ICS.UserDefined.Before, AA_Converting, 2411 CCK); 2412 if (Res.isInvalid()) 2413 return ExprError(); 2414 From = Res.take(); 2415 } 2416 2417 ExprResult CastArg 2418 = BuildCXXCastArgument(*this, 2419 From->getLocStart(), 2420 ToType.getNonReferenceType(), 2421 CastKind, cast<CXXMethodDecl>(FD), 2422 ICS.UserDefined.FoundConversionFunction, 2423 ICS.UserDefined.HadMultipleCandidates, 2424 From); 2425 2426 if (CastArg.isInvalid()) 2427 return ExprError(); 2428 2429 From = CastArg.take(); 2430 2431 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2432 AA_Converting, CCK); 2433 } 2434 2435 case ImplicitConversionSequence::AmbiguousConversion: 2436 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2437 PDiag(diag::err_typecheck_ambiguous_condition) 2438 << From->getSourceRange()); 2439 return ExprError(); 2440 2441 case ImplicitConversionSequence::EllipsisConversion: 2442 llvm_unreachable("Cannot perform an ellipsis conversion"); 2443 2444 case ImplicitConversionSequence::BadConversion: 2445 return ExprError(); 2446 } 2447 2448 // Everything went well. 2449 return Owned(From); 2450} 2451 2452/// PerformImplicitConversion - Perform an implicit conversion of the 2453/// expression From to the type ToType by following the standard 2454/// conversion sequence SCS. Returns the converted 2455/// expression. Flavor is the context in which we're performing this 2456/// conversion, for use in error messages. 2457ExprResult 2458Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2459 const StandardConversionSequence& SCS, 2460 AssignmentAction Action, 2461 CheckedConversionKind CCK) { 2462 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2463 2464 // Overall FIXME: we are recomputing too many types here and doing far too 2465 // much extra work. What this means is that we need to keep track of more 2466 // information that is computed when we try the implicit conversion initially, 2467 // so that we don't need to recompute anything here. 2468 QualType FromType = From->getType(); 2469 2470 if (SCS.CopyConstructor) { 2471 // FIXME: When can ToType be a reference type? 2472 assert(!ToType->isReferenceType()); 2473 if (SCS.Second == ICK_Derived_To_Base) { 2474 SmallVector<Expr*, 8> ConstructorArgs; 2475 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2476 From, /*FIXME:ConstructLoc*/SourceLocation(), 2477 ConstructorArgs)) 2478 return ExprError(); 2479 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2480 ToType, SCS.CopyConstructor, 2481 ConstructorArgs, 2482 /*HadMultipleCandidates*/ false, 2483 /*ListInit*/ false, /*ZeroInit*/ false, 2484 CXXConstructExpr::CK_Complete, 2485 SourceRange()); 2486 } 2487 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2488 ToType, SCS.CopyConstructor, 2489 From, /*HadMultipleCandidates*/ false, 2490 /*ListInit*/ false, /*ZeroInit*/ false, 2491 CXXConstructExpr::CK_Complete, 2492 SourceRange()); 2493 } 2494 2495 // Resolve overloaded function references. 2496 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2497 DeclAccessPair Found; 2498 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2499 true, Found); 2500 if (!Fn) 2501 return ExprError(); 2502 2503 if (DiagnoseUseOfDecl(Fn, From->getLocStart())) 2504 return ExprError(); 2505 2506 From = FixOverloadedFunctionReference(From, Found, Fn); 2507 FromType = From->getType(); 2508 } 2509 2510 // Perform the first implicit conversion. 2511 switch (SCS.First) { 2512 case ICK_Identity: 2513 // Nothing to do. 2514 break; 2515 2516 case ICK_Lvalue_To_Rvalue: { 2517 assert(From->getObjectKind() != OK_ObjCProperty); 2518 FromType = FromType.getUnqualifiedType(); 2519 ExprResult FromRes = DefaultLvalueConversion(From); 2520 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2521 From = FromRes.take(); 2522 break; 2523 } 2524 2525 case ICK_Array_To_Pointer: 2526 FromType = Context.getArrayDecayedType(FromType); 2527 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2528 VK_RValue, /*BasePath=*/0, CCK).take(); 2529 break; 2530 2531 case ICK_Function_To_Pointer: 2532 FromType = Context.getPointerType(FromType); 2533 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2534 VK_RValue, /*BasePath=*/0, CCK).take(); 2535 break; 2536 2537 default: 2538 llvm_unreachable("Improper first standard conversion"); 2539 } 2540 2541 // Perform the second implicit conversion 2542 switch (SCS.Second) { 2543 case ICK_Identity: 2544 // If both sides are functions (or pointers/references to them), there could 2545 // be incompatible exception declarations. 2546 if (CheckExceptionSpecCompatibility(From, ToType)) 2547 return ExprError(); 2548 // Nothing else to do. 2549 break; 2550 2551 case ICK_NoReturn_Adjustment: 2552 // If both sides are functions (or pointers/references to them), there could 2553 // be incompatible exception declarations. 2554 if (CheckExceptionSpecCompatibility(From, ToType)) 2555 return ExprError(); 2556 2557 From = ImpCastExprToType(From, ToType, CK_NoOp, 2558 VK_RValue, /*BasePath=*/0, CCK).take(); 2559 break; 2560 2561 case ICK_Integral_Promotion: 2562 case ICK_Integral_Conversion: 2563 if (ToType->isBooleanType()) { 2564 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() && 2565 SCS.Second == ICK_Integral_Promotion && 2566 "only enums with fixed underlying type can promote to bool"); 2567 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean, 2568 VK_RValue, /*BasePath=*/0, CCK).take(); 2569 } else { 2570 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2571 VK_RValue, /*BasePath=*/0, CCK).take(); 2572 } 2573 break; 2574 2575 case ICK_Floating_Promotion: 2576 case ICK_Floating_Conversion: 2577 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2578 VK_RValue, /*BasePath=*/0, CCK).take(); 2579 break; 2580 2581 case ICK_Complex_Promotion: 2582 case ICK_Complex_Conversion: { 2583 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2584 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2585 CastKind CK; 2586 if (FromEl->isRealFloatingType()) { 2587 if (ToEl->isRealFloatingType()) 2588 CK = CK_FloatingComplexCast; 2589 else 2590 CK = CK_FloatingComplexToIntegralComplex; 2591 } else if (ToEl->isRealFloatingType()) { 2592 CK = CK_IntegralComplexToFloatingComplex; 2593 } else { 2594 CK = CK_IntegralComplexCast; 2595 } 2596 From = ImpCastExprToType(From, ToType, CK, 2597 VK_RValue, /*BasePath=*/0, CCK).take(); 2598 break; 2599 } 2600 2601 case ICK_Floating_Integral: 2602 if (ToType->isRealFloatingType()) 2603 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2604 VK_RValue, /*BasePath=*/0, CCK).take(); 2605 else 2606 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2607 VK_RValue, /*BasePath=*/0, CCK).take(); 2608 break; 2609 2610 case ICK_Compatible_Conversion: 2611 From = ImpCastExprToType(From, ToType, CK_NoOp, 2612 VK_RValue, /*BasePath=*/0, CCK).take(); 2613 break; 2614 2615 case ICK_Writeback_Conversion: 2616 case ICK_Pointer_Conversion: { 2617 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2618 // Diagnose incompatible Objective-C conversions 2619 if (Action == AA_Initializing || Action == AA_Assigning) 2620 Diag(From->getLocStart(), 2621 diag::ext_typecheck_convert_incompatible_pointer) 2622 << ToType << From->getType() << Action 2623 << From->getSourceRange() << 0; 2624 else 2625 Diag(From->getLocStart(), 2626 diag::ext_typecheck_convert_incompatible_pointer) 2627 << From->getType() << ToType << Action 2628 << From->getSourceRange() << 0; 2629 2630 if (From->getType()->isObjCObjectPointerType() && 2631 ToType->isObjCObjectPointerType()) 2632 EmitRelatedResultTypeNote(From); 2633 } 2634 else if (getLangOpts().ObjCAutoRefCount && 2635 !CheckObjCARCUnavailableWeakConversion(ToType, 2636 From->getType())) { 2637 if (Action == AA_Initializing) 2638 Diag(From->getLocStart(), 2639 diag::err_arc_weak_unavailable_assign); 2640 else 2641 Diag(From->getLocStart(), 2642 diag::err_arc_convesion_of_weak_unavailable) 2643 << (Action == AA_Casting) << From->getType() << ToType 2644 << From->getSourceRange(); 2645 } 2646 2647 CastKind Kind = CK_Invalid; 2648 CXXCastPath BasePath; 2649 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2650 return ExprError(); 2651 2652 // Make sure we extend blocks if necessary. 2653 // FIXME: doing this here is really ugly. 2654 if (Kind == CK_BlockPointerToObjCPointerCast) { 2655 ExprResult E = From; 2656 (void) PrepareCastToObjCObjectPointer(E); 2657 From = E.take(); 2658 } 2659 2660 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2661 .take(); 2662 break; 2663 } 2664 2665 case ICK_Pointer_Member: { 2666 CastKind Kind = CK_Invalid; 2667 CXXCastPath BasePath; 2668 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2669 return ExprError(); 2670 if (CheckExceptionSpecCompatibility(From, ToType)) 2671 return ExprError(); 2672 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2673 .take(); 2674 break; 2675 } 2676 2677 case ICK_Boolean_Conversion: 2678 // Perform half-to-boolean conversion via float. 2679 if (From->getType()->isHalfType()) { 2680 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2681 FromType = Context.FloatTy; 2682 } 2683 2684 From = ImpCastExprToType(From, Context.BoolTy, 2685 ScalarTypeToBooleanCastKind(FromType), 2686 VK_RValue, /*BasePath=*/0, CCK).take(); 2687 break; 2688 2689 case ICK_Derived_To_Base: { 2690 CXXCastPath BasePath; 2691 if (CheckDerivedToBaseConversion(From->getType(), 2692 ToType.getNonReferenceType(), 2693 From->getLocStart(), 2694 From->getSourceRange(), 2695 &BasePath, 2696 CStyle)) 2697 return ExprError(); 2698 2699 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2700 CK_DerivedToBase, From->getValueKind(), 2701 &BasePath, CCK).take(); 2702 break; 2703 } 2704 2705 case ICK_Vector_Conversion: 2706 From = ImpCastExprToType(From, ToType, CK_BitCast, 2707 VK_RValue, /*BasePath=*/0, CCK).take(); 2708 break; 2709 2710 case ICK_Vector_Splat: 2711 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2712 VK_RValue, /*BasePath=*/0, CCK).take(); 2713 break; 2714 2715 case ICK_Complex_Real: 2716 // Case 1. x -> _Complex y 2717 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2718 QualType ElType = ToComplex->getElementType(); 2719 bool isFloatingComplex = ElType->isRealFloatingType(); 2720 2721 // x -> y 2722 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2723 // do nothing 2724 } else if (From->getType()->isRealFloatingType()) { 2725 From = ImpCastExprToType(From, ElType, 2726 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2727 } else { 2728 assert(From->getType()->isIntegerType()); 2729 From = ImpCastExprToType(From, ElType, 2730 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2731 } 2732 // y -> _Complex y 2733 From = ImpCastExprToType(From, ToType, 2734 isFloatingComplex ? CK_FloatingRealToComplex 2735 : CK_IntegralRealToComplex).take(); 2736 2737 // Case 2. _Complex x -> y 2738 } else { 2739 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2740 assert(FromComplex); 2741 2742 QualType ElType = FromComplex->getElementType(); 2743 bool isFloatingComplex = ElType->isRealFloatingType(); 2744 2745 // _Complex x -> x 2746 From = ImpCastExprToType(From, ElType, 2747 isFloatingComplex ? CK_FloatingComplexToReal 2748 : CK_IntegralComplexToReal, 2749 VK_RValue, /*BasePath=*/0, CCK).take(); 2750 2751 // x -> y 2752 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2753 // do nothing 2754 } else if (ToType->isRealFloatingType()) { 2755 From = ImpCastExprToType(From, ToType, 2756 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2757 VK_RValue, /*BasePath=*/0, CCK).take(); 2758 } else { 2759 assert(ToType->isIntegerType()); 2760 From = ImpCastExprToType(From, ToType, 2761 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2762 VK_RValue, /*BasePath=*/0, CCK).take(); 2763 } 2764 } 2765 break; 2766 2767 case ICK_Block_Pointer_Conversion: { 2768 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2769 VK_RValue, /*BasePath=*/0, CCK).take(); 2770 break; 2771 } 2772 2773 case ICK_TransparentUnionConversion: { 2774 ExprResult FromRes = Owned(From); 2775 Sema::AssignConvertType ConvTy = 2776 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2777 if (FromRes.isInvalid()) 2778 return ExprError(); 2779 From = FromRes.take(); 2780 assert ((ConvTy == Sema::Compatible) && 2781 "Improper transparent union conversion"); 2782 (void)ConvTy; 2783 break; 2784 } 2785 2786 case ICK_Zero_Event_Conversion: 2787 From = ImpCastExprToType(From, ToType, 2788 CK_ZeroToOCLEvent, 2789 From->getValueKind()).take(); 2790 break; 2791 2792 case ICK_Lvalue_To_Rvalue: 2793 case ICK_Array_To_Pointer: 2794 case ICK_Function_To_Pointer: 2795 case ICK_Qualification: 2796 case ICK_Num_Conversion_Kinds: 2797 llvm_unreachable("Improper second standard conversion"); 2798 } 2799 2800 switch (SCS.Third) { 2801 case ICK_Identity: 2802 // Nothing to do. 2803 break; 2804 2805 case ICK_Qualification: { 2806 // The qualification keeps the category of the inner expression, unless the 2807 // target type isn't a reference. 2808 ExprValueKind VK = ToType->isReferenceType() ? 2809 From->getValueKind() : VK_RValue; 2810 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2811 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2812 2813 if (SCS.DeprecatedStringLiteralToCharPtr && 2814 !getLangOpts().WritableStrings) 2815 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2816 << ToType.getNonReferenceType(); 2817 2818 break; 2819 } 2820 2821 default: 2822 llvm_unreachable("Improper third standard conversion"); 2823 } 2824 2825 // If this conversion sequence involved a scalar -> atomic conversion, perform 2826 // that conversion now. 2827 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) 2828 if (Context.hasSameType(ToAtomic->getValueType(), From->getType())) 2829 From = ImpCastExprToType(From, ToType, CK_NonAtomicToAtomic, VK_RValue, 0, 2830 CCK).take(); 2831 2832 return Owned(From); 2833} 2834 2835ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2836 SourceLocation KWLoc, 2837 ParsedType Ty, 2838 SourceLocation RParen) { 2839 TypeSourceInfo *TSInfo; 2840 QualType T = GetTypeFromParser(Ty, &TSInfo); 2841 2842 if (!TSInfo) 2843 TSInfo = Context.getTrivialTypeSourceInfo(T); 2844 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2845} 2846 2847/// \brief Check the completeness of a type in a unary type trait. 2848/// 2849/// If the particular type trait requires a complete type, tries to complete 2850/// it. If completing the type fails, a diagnostic is emitted and false 2851/// returned. If completing the type succeeds or no completion was required, 2852/// returns true. 2853static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2854 UnaryTypeTrait UTT, 2855 SourceLocation Loc, 2856 QualType ArgTy) { 2857 // C++0x [meta.unary.prop]p3: 2858 // For all of the class templates X declared in this Clause, instantiating 2859 // that template with a template argument that is a class template 2860 // specialization may result in the implicit instantiation of the template 2861 // argument if and only if the semantics of X require that the argument 2862 // must be a complete type. 2863 // We apply this rule to all the type trait expressions used to implement 2864 // these class templates. We also try to follow any GCC documented behavior 2865 // in these expressions to ensure portability of standard libraries. 2866 switch (UTT) { 2867 // is_complete_type somewhat obviously cannot require a complete type. 2868 case UTT_IsCompleteType: 2869 // Fall-through 2870 2871 // These traits are modeled on the type predicates in C++0x 2872 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2873 // requiring a complete type, as whether or not they return true cannot be 2874 // impacted by the completeness of the type. 2875 case UTT_IsVoid: 2876 case UTT_IsIntegral: 2877 case UTT_IsFloatingPoint: 2878 case UTT_IsArray: 2879 case UTT_IsPointer: 2880 case UTT_IsLvalueReference: 2881 case UTT_IsRvalueReference: 2882 case UTT_IsMemberFunctionPointer: 2883 case UTT_IsMemberObjectPointer: 2884 case UTT_IsEnum: 2885 case UTT_IsUnion: 2886 case UTT_IsClass: 2887 case UTT_IsFunction: 2888 case UTT_IsReference: 2889 case UTT_IsArithmetic: 2890 case UTT_IsFundamental: 2891 case UTT_IsObject: 2892 case UTT_IsScalar: 2893 case UTT_IsCompound: 2894 case UTT_IsMemberPointer: 2895 // Fall-through 2896 2897 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2898 // which requires some of its traits to have the complete type. However, 2899 // the completeness of the type cannot impact these traits' semantics, and 2900 // so they don't require it. This matches the comments on these traits in 2901 // Table 49. 2902 case UTT_IsConst: 2903 case UTT_IsVolatile: 2904 case UTT_IsSigned: 2905 case UTT_IsUnsigned: 2906 return true; 2907 2908 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2909 // applied to a complete type. 2910 case UTT_IsTrivial: 2911 case UTT_IsTriviallyCopyable: 2912 case UTT_IsStandardLayout: 2913 case UTT_IsPOD: 2914 case UTT_IsLiteral: 2915 case UTT_IsEmpty: 2916 case UTT_IsPolymorphic: 2917 case UTT_IsAbstract: 2918 case UTT_IsInterfaceClass: 2919 // Fall-through 2920 2921 // These traits require a complete type. 2922 case UTT_IsFinal: 2923 2924 // These trait expressions are designed to help implement predicates in 2925 // [meta.unary.prop] despite not being named the same. They are specified 2926 // by both GCC and the Embarcadero C++ compiler, and require the complete 2927 // type due to the overarching C++0x type predicates being implemented 2928 // requiring the complete type. 2929 case UTT_HasNothrowAssign: 2930 case UTT_HasNothrowConstructor: 2931 case UTT_HasNothrowCopy: 2932 case UTT_HasTrivialAssign: 2933 case UTT_HasTrivialDefaultConstructor: 2934 case UTT_HasTrivialCopy: 2935 case UTT_HasTrivialDestructor: 2936 case UTT_HasVirtualDestructor: 2937 // Arrays of unknown bound are expressly allowed. 2938 QualType ElTy = ArgTy; 2939 if (ArgTy->isIncompleteArrayType()) 2940 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 2941 2942 // The void type is expressly allowed. 2943 if (ElTy->isVoidType()) 2944 return true; 2945 2946 return !S.RequireCompleteType( 2947 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 2948 } 2949 llvm_unreachable("Type trait not handled by switch"); 2950} 2951 2952static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 2953 SourceLocation KeyLoc, QualType T) { 2954 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 2955 2956 ASTContext &C = Self.Context; 2957 switch(UTT) { 2958 // Type trait expressions corresponding to the primary type category 2959 // predicates in C++0x [meta.unary.cat]. 2960 case UTT_IsVoid: 2961 return T->isVoidType(); 2962 case UTT_IsIntegral: 2963 return T->isIntegralType(C); 2964 case UTT_IsFloatingPoint: 2965 return T->isFloatingType(); 2966 case UTT_IsArray: 2967 return T->isArrayType(); 2968 case UTT_IsPointer: 2969 return T->isPointerType(); 2970 case UTT_IsLvalueReference: 2971 return T->isLValueReferenceType(); 2972 case UTT_IsRvalueReference: 2973 return T->isRValueReferenceType(); 2974 case UTT_IsMemberFunctionPointer: 2975 return T->isMemberFunctionPointerType(); 2976 case UTT_IsMemberObjectPointer: 2977 return T->isMemberDataPointerType(); 2978 case UTT_IsEnum: 2979 return T->isEnumeralType(); 2980 case UTT_IsUnion: 2981 return T->isUnionType(); 2982 case UTT_IsClass: 2983 return T->isClassType() || T->isStructureType() || T->isInterfaceType(); 2984 case UTT_IsFunction: 2985 return T->isFunctionType(); 2986 2987 // Type trait expressions which correspond to the convenient composition 2988 // predicates in C++0x [meta.unary.comp]. 2989 case UTT_IsReference: 2990 return T->isReferenceType(); 2991 case UTT_IsArithmetic: 2992 return T->isArithmeticType() && !T->isEnumeralType(); 2993 case UTT_IsFundamental: 2994 return T->isFundamentalType(); 2995 case UTT_IsObject: 2996 return T->isObjectType(); 2997 case UTT_IsScalar: 2998 // Note: semantic analysis depends on Objective-C lifetime types to be 2999 // considered scalar types. However, such types do not actually behave 3000 // like scalar types at run time (since they may require retain/release 3001 // operations), so we report them as non-scalar. 3002 if (T->isObjCLifetimeType()) { 3003 switch (T.getObjCLifetime()) { 3004 case Qualifiers::OCL_None: 3005 case Qualifiers::OCL_ExplicitNone: 3006 return true; 3007 3008 case Qualifiers::OCL_Strong: 3009 case Qualifiers::OCL_Weak: 3010 case Qualifiers::OCL_Autoreleasing: 3011 return false; 3012 } 3013 } 3014 3015 return T->isScalarType(); 3016 case UTT_IsCompound: 3017 return T->isCompoundType(); 3018 case UTT_IsMemberPointer: 3019 return T->isMemberPointerType(); 3020 3021 // Type trait expressions which correspond to the type property predicates 3022 // in C++0x [meta.unary.prop]. 3023 case UTT_IsConst: 3024 return T.isConstQualified(); 3025 case UTT_IsVolatile: 3026 return T.isVolatileQualified(); 3027 case UTT_IsTrivial: 3028 return T.isTrivialType(Self.Context); 3029 case UTT_IsTriviallyCopyable: 3030 return T.isTriviallyCopyableType(Self.Context); 3031 case UTT_IsStandardLayout: 3032 return T->isStandardLayoutType(); 3033 case UTT_IsPOD: 3034 return T.isPODType(Self.Context); 3035 case UTT_IsLiteral: 3036 return T->isLiteralType(); 3037 case UTT_IsEmpty: 3038 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3039 return !RD->isUnion() && RD->isEmpty(); 3040 return false; 3041 case UTT_IsPolymorphic: 3042 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3043 return RD->isPolymorphic(); 3044 return false; 3045 case UTT_IsAbstract: 3046 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3047 return RD->isAbstract(); 3048 return false; 3049 case UTT_IsInterfaceClass: 3050 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3051 return RD->isInterface(); 3052 return false; 3053 case UTT_IsFinal: 3054 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3055 return RD->hasAttr<FinalAttr>(); 3056 return false; 3057 case UTT_IsSigned: 3058 return T->isSignedIntegerType(); 3059 case UTT_IsUnsigned: 3060 return T->isUnsignedIntegerType(); 3061 3062 // Type trait expressions which query classes regarding their construction, 3063 // destruction, and copying. Rather than being based directly on the 3064 // related type predicates in the standard, they are specified by both 3065 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 3066 // specifications. 3067 // 3068 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 3069 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3070 // 3071 // Note that these builtins do not behave as documented in g++: if a class 3072 // has both a trivial and a non-trivial special member of a particular kind, 3073 // they return false! For now, we emulate this behavior. 3074 // FIXME: This appears to be a g++ bug: more complex cases reveal that it 3075 // does not correctly compute triviality in the presence of multiple special 3076 // members of the same kind. Revisit this once the g++ bug is fixed. 3077 case UTT_HasTrivialDefaultConstructor: 3078 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3079 // If __is_pod (type) is true then the trait is true, else if type is 3080 // a cv class or union type (or array thereof) with a trivial default 3081 // constructor ([class.ctor]) then the trait is true, else it is false. 3082 if (T.isPODType(Self.Context)) 3083 return true; 3084 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3085 return RD->hasTrivialDefaultConstructor() && 3086 !RD->hasNonTrivialDefaultConstructor(); 3087 return false; 3088 case UTT_HasTrivialCopy: 3089 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3090 // If __is_pod (type) is true or type is a reference type then 3091 // the trait is true, else if type is a cv class or union type 3092 // with a trivial copy constructor ([class.copy]) then the trait 3093 // is true, else it is false. 3094 if (T.isPODType(Self.Context) || T->isReferenceType()) 3095 return true; 3096 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3097 return RD->hasTrivialCopyConstructor() && 3098 !RD->hasNonTrivialCopyConstructor(); 3099 return false; 3100 case UTT_HasTrivialAssign: 3101 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3102 // If type is const qualified or is a reference type then the 3103 // trait is false. Otherwise if __is_pod (type) is true then the 3104 // trait is true, else if type is a cv class or union type with 3105 // a trivial copy assignment ([class.copy]) then the trait is 3106 // true, else it is false. 3107 // Note: the const and reference restrictions are interesting, 3108 // given that const and reference members don't prevent a class 3109 // from having a trivial copy assignment operator (but do cause 3110 // errors if the copy assignment operator is actually used, q.v. 3111 // [class.copy]p12). 3112 3113 if (T.isConstQualified()) 3114 return false; 3115 if (T.isPODType(Self.Context)) 3116 return true; 3117 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3118 return RD->hasTrivialCopyAssignment() && 3119 !RD->hasNonTrivialCopyAssignment(); 3120 return false; 3121 case UTT_HasTrivialDestructor: 3122 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3123 // If __is_pod (type) is true or type is a reference type 3124 // then the trait is true, else if type is a cv class or union 3125 // type (or array thereof) with a trivial destructor 3126 // ([class.dtor]) then the trait is true, else it is 3127 // false. 3128 if (T.isPODType(Self.Context) || T->isReferenceType()) 3129 return true; 3130 3131 // Objective-C++ ARC: autorelease types don't require destruction. 3132 if (T->isObjCLifetimeType() && 3133 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3134 return true; 3135 3136 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) 3137 return RD->hasTrivialDestructor(); 3138 return false; 3139 // TODO: Propagate nothrowness for implicitly declared special members. 3140 case UTT_HasNothrowAssign: 3141 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3142 // If type is const qualified or is a reference type then the 3143 // trait is false. Otherwise if __has_trivial_assign (type) 3144 // is true then the trait is true, else if type is a cv class 3145 // or union type with copy assignment operators that are known 3146 // not to throw an exception then the trait is true, else it is 3147 // false. 3148 if (C.getBaseElementType(T).isConstQualified()) 3149 return false; 3150 if (T->isReferenceType()) 3151 return false; 3152 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3153 return true; 3154 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) { 3155 if (RD->hasTrivialCopyAssignment() && !RD->hasNonTrivialCopyAssignment()) 3156 return true; 3157 3158 bool FoundAssign = false; 3159 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(OO_Equal); 3160 LookupResult Res(Self, DeclarationNameInfo(Name, KeyLoc), 3161 Sema::LookupOrdinaryName); 3162 if (Self.LookupQualifiedName(Res, RD)) { 3163 Res.suppressDiagnostics(); 3164 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3165 Op != OpEnd; ++Op) { 3166 if (isa<FunctionTemplateDecl>(*Op)) 3167 continue; 3168 3169 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3170 if (Operator->isCopyAssignmentOperator()) { 3171 FoundAssign = true; 3172 const FunctionProtoType *CPT 3173 = Operator->getType()->getAs<FunctionProtoType>(); 3174 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3175 if (!CPT) 3176 return false; 3177 if (!CPT->isNothrow(Self.Context)) 3178 return false; 3179 } 3180 } 3181 } 3182 3183 return FoundAssign; 3184 } 3185 return false; 3186 case UTT_HasNothrowCopy: 3187 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3188 // If __has_trivial_copy (type) is true then the trait is true, else 3189 // if type is a cv class or union type with copy constructors that are 3190 // known not to throw an exception then the trait is true, else it is 3191 // false. 3192 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3193 return true; 3194 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) { 3195 if (RD->hasTrivialCopyConstructor() && 3196 !RD->hasNonTrivialCopyConstructor()) 3197 return true; 3198 3199 bool FoundConstructor = false; 3200 unsigned FoundTQs; 3201 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3202 for (DeclContext::lookup_const_iterator Con = R.begin(), 3203 ConEnd = R.end(); Con != ConEnd; ++Con) { 3204 // A template constructor is never a copy constructor. 3205 // FIXME: However, it may actually be selected at the actual overload 3206 // resolution point. 3207 if (isa<FunctionTemplateDecl>(*Con)) 3208 continue; 3209 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3210 if (Constructor->isCopyConstructor(FoundTQs)) { 3211 FoundConstructor = true; 3212 const FunctionProtoType *CPT 3213 = Constructor->getType()->getAs<FunctionProtoType>(); 3214 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3215 if (!CPT) 3216 return false; 3217 // FIXME: check whether evaluating default arguments can throw. 3218 // For now, we'll be conservative and assume that they can throw. 3219 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3220 return false; 3221 } 3222 } 3223 3224 return FoundConstructor; 3225 } 3226 return false; 3227 case UTT_HasNothrowConstructor: 3228 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3229 // If __has_trivial_constructor (type) is true then the trait is 3230 // true, else if type is a cv class or union type (or array 3231 // thereof) with a default constructor that is known not to 3232 // throw an exception then the trait is true, else it is false. 3233 if (T.isPODType(C) || T->isObjCLifetimeType()) 3234 return true; 3235 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) { 3236 if (RD->hasTrivialDefaultConstructor() && 3237 !RD->hasNonTrivialDefaultConstructor()) 3238 return true; 3239 3240 DeclContext::lookup_const_result R = Self.LookupConstructors(RD); 3241 for (DeclContext::lookup_const_iterator Con = R.begin(), 3242 ConEnd = R.end(); Con != ConEnd; ++Con) { 3243 // FIXME: In C++0x, a constructor template can be a default constructor. 3244 if (isa<FunctionTemplateDecl>(*Con)) 3245 continue; 3246 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3247 if (Constructor->isDefaultConstructor()) { 3248 const FunctionProtoType *CPT 3249 = Constructor->getType()->getAs<FunctionProtoType>(); 3250 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT); 3251 if (!CPT) 3252 return false; 3253 // TODO: check whether evaluating default arguments can throw. 3254 // For now, we'll be conservative and assume that they can throw. 3255 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3256 } 3257 } 3258 } 3259 return false; 3260 case UTT_HasVirtualDestructor: 3261 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3262 // If type is a class type with a virtual destructor ([class.dtor]) 3263 // then the trait is true, else it is false. 3264 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 3265 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3266 return Destructor->isVirtual(); 3267 return false; 3268 3269 // These type trait expressions are modeled on the specifications for the 3270 // Embarcadero C++0x type trait functions: 3271 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3272 case UTT_IsCompleteType: 3273 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3274 // Returns True if and only if T is a complete type at the point of the 3275 // function call. 3276 return !T->isIncompleteType(); 3277 } 3278 llvm_unreachable("Type trait not covered by switch"); 3279} 3280 3281ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3282 SourceLocation KWLoc, 3283 TypeSourceInfo *TSInfo, 3284 SourceLocation RParen) { 3285 QualType T = TSInfo->getType(); 3286 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3287 return ExprError(); 3288 3289 bool Value = false; 3290 if (!T->isDependentType()) 3291 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3292 3293 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3294 RParen, Context.BoolTy)); 3295} 3296 3297ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3298 SourceLocation KWLoc, 3299 ParsedType LhsTy, 3300 ParsedType RhsTy, 3301 SourceLocation RParen) { 3302 TypeSourceInfo *LhsTSInfo; 3303 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3304 if (!LhsTSInfo) 3305 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3306 3307 TypeSourceInfo *RhsTSInfo; 3308 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3309 if (!RhsTSInfo) 3310 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3311 3312 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3313} 3314 3315/// \brief Determine whether T has a non-trivial Objective-C lifetime in 3316/// ARC mode. 3317static bool hasNontrivialObjCLifetime(QualType T) { 3318 switch (T.getObjCLifetime()) { 3319 case Qualifiers::OCL_ExplicitNone: 3320 return false; 3321 3322 case Qualifiers::OCL_Strong: 3323 case Qualifiers::OCL_Weak: 3324 case Qualifiers::OCL_Autoreleasing: 3325 return true; 3326 3327 case Qualifiers::OCL_None: 3328 return T->isObjCLifetimeType(); 3329 } 3330 3331 llvm_unreachable("Unknown ObjC lifetime qualifier"); 3332} 3333 3334static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc, 3335 ArrayRef<TypeSourceInfo *> Args, 3336 SourceLocation RParenLoc) { 3337 switch (Kind) { 3338 case clang::TT_IsTriviallyConstructible: { 3339 // C++11 [meta.unary.prop]: 3340 // is_trivially_constructible is defined as: 3341 // 3342 // is_constructible<T, Args...>::value is true and the variable 3343 // definition for is_constructible, as defined below, is known to call no 3344 // operation that is not trivial. 3345 // 3346 // The predicate condition for a template specialization 3347 // is_constructible<T, Args...> shall be satisfied if and only if the 3348 // following variable definition would be well-formed for some invented 3349 // variable t: 3350 // 3351 // T t(create<Args>()...); 3352 if (Args.empty()) { 3353 S.Diag(KWLoc, diag::err_type_trait_arity) 3354 << 1 << 1 << 1 << (int)Args.size(); 3355 return false; 3356 } 3357 3358 bool SawVoid = false; 3359 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3360 if (Args[I]->getType()->isVoidType()) { 3361 SawVoid = true; 3362 continue; 3363 } 3364 3365 if (!Args[I]->getType()->isIncompleteType() && 3366 S.RequireCompleteType(KWLoc, Args[I]->getType(), 3367 diag::err_incomplete_type_used_in_type_trait_expr)) 3368 return false; 3369 } 3370 3371 // If any argument was 'void', of course it won't type-check. 3372 if (SawVoid) 3373 return false; 3374 3375 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs; 3376 SmallVector<Expr *, 2> ArgExprs; 3377 ArgExprs.reserve(Args.size() - 1); 3378 for (unsigned I = 1, N = Args.size(); I != N; ++I) { 3379 QualType T = Args[I]->getType(); 3380 if (T->isObjectType() || T->isFunctionType()) 3381 T = S.Context.getRValueReferenceType(T); 3382 OpaqueArgExprs.push_back( 3383 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(), 3384 T.getNonLValueExprType(S.Context), 3385 Expr::getValueKindForType(T))); 3386 ArgExprs.push_back(&OpaqueArgExprs.back()); 3387 } 3388 3389 // Perform the initialization in an unevaluated context within a SFINAE 3390 // trap at translation unit scope. 3391 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated); 3392 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true); 3393 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); 3394 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0])); 3395 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc, 3396 RParenLoc)); 3397 InitializationSequence Init(S, To, InitKind, 3398 ArgExprs.begin(), ArgExprs.size()); 3399 if (Init.Failed()) 3400 return false; 3401 3402 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs); 3403 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3404 return false; 3405 3406 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3407 // lifetime, this is a non-trivial construction. 3408 if (S.getLangOpts().ObjCAutoRefCount && 3409 hasNontrivialObjCLifetime(Args[0]->getType().getNonReferenceType())) 3410 return false; 3411 3412 // The initialization succeeded; now make sure there are no non-trivial 3413 // calls. 3414 return !Result.get()->hasNonTrivialCall(S.Context); 3415 } 3416 } 3417 3418 return false; 3419} 3420 3421ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3422 ArrayRef<TypeSourceInfo *> Args, 3423 SourceLocation RParenLoc) { 3424 bool Dependent = false; 3425 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3426 if (Args[I]->getType()->isDependentType()) { 3427 Dependent = true; 3428 break; 3429 } 3430 } 3431 3432 bool Value = false; 3433 if (!Dependent) 3434 Value = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc); 3435 3436 return TypeTraitExpr::Create(Context, Context.BoolTy, KWLoc, Kind, 3437 Args, RParenLoc, Value); 3438} 3439 3440ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3441 ArrayRef<ParsedType> Args, 3442 SourceLocation RParenLoc) { 3443 SmallVector<TypeSourceInfo *, 4> ConvertedArgs; 3444 ConvertedArgs.reserve(Args.size()); 3445 3446 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3447 TypeSourceInfo *TInfo; 3448 QualType T = GetTypeFromParser(Args[I], &TInfo); 3449 if (!TInfo) 3450 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc); 3451 3452 ConvertedArgs.push_back(TInfo); 3453 } 3454 3455 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc); 3456} 3457 3458static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3459 QualType LhsT, QualType RhsT, 3460 SourceLocation KeyLoc) { 3461 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3462 "Cannot evaluate traits of dependent types"); 3463 3464 switch(BTT) { 3465 case BTT_IsBaseOf: { 3466 // C++0x [meta.rel]p2 3467 // Base is a base class of Derived without regard to cv-qualifiers or 3468 // Base and Derived are not unions and name the same class type without 3469 // regard to cv-qualifiers. 3470 3471 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3472 if (!lhsRecord) return false; 3473 3474 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3475 if (!rhsRecord) return false; 3476 3477 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3478 == (lhsRecord == rhsRecord)); 3479 3480 if (lhsRecord == rhsRecord) 3481 return !lhsRecord->getDecl()->isUnion(); 3482 3483 // C++0x [meta.rel]p2: 3484 // If Base and Derived are class types and are different types 3485 // (ignoring possible cv-qualifiers) then Derived shall be a 3486 // complete type. 3487 if (Self.RequireCompleteType(KeyLoc, RhsT, 3488 diag::err_incomplete_type_used_in_type_trait_expr)) 3489 return false; 3490 3491 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3492 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3493 } 3494 case BTT_IsSame: 3495 return Self.Context.hasSameType(LhsT, RhsT); 3496 case BTT_TypeCompatible: 3497 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3498 RhsT.getUnqualifiedType()); 3499 case BTT_IsConvertible: 3500 case BTT_IsConvertibleTo: { 3501 // C++0x [meta.rel]p4: 3502 // Given the following function prototype: 3503 // 3504 // template <class T> 3505 // typename add_rvalue_reference<T>::type create(); 3506 // 3507 // the predicate condition for a template specialization 3508 // is_convertible<From, To> shall be satisfied if and only if 3509 // the return expression in the following code would be 3510 // well-formed, including any implicit conversions to the return 3511 // type of the function: 3512 // 3513 // To test() { 3514 // return create<From>(); 3515 // } 3516 // 3517 // Access checking is performed as if in a context unrelated to To and 3518 // From. Only the validity of the immediate context of the expression 3519 // of the return-statement (including conversions to the return type) 3520 // is considered. 3521 // 3522 // We model the initialization as a copy-initialization of a temporary 3523 // of the appropriate type, which for this expression is identical to the 3524 // return statement (since NRVO doesn't apply). 3525 3526 // Functions aren't allowed to return function or array types. 3527 if (RhsT->isFunctionType() || RhsT->isArrayType()) 3528 return false; 3529 3530 // A return statement in a void function must have void type. 3531 if (RhsT->isVoidType()) 3532 return LhsT->isVoidType(); 3533 3534 // A function definition requires a complete, non-abstract return type. 3535 if (Self.RequireCompleteType(KeyLoc, RhsT, 0) || 3536 Self.RequireNonAbstractType(KeyLoc, RhsT, 0)) 3537 return false; 3538 3539 // Compute the result of add_rvalue_reference. 3540 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3541 LhsT = Self.Context.getRValueReferenceType(LhsT); 3542 3543 // Build a fake source and destination for initialization. 3544 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3545 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3546 Expr::getValueKindForType(LhsT)); 3547 Expr *FromPtr = &From; 3548 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3549 SourceLocation())); 3550 3551 // Perform the initialization in an unevaluated context within a SFINAE 3552 // trap at translation unit scope. 3553 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3554 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3555 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3556 InitializationSequence Init(Self, To, Kind, &FromPtr, 1); 3557 if (Init.Failed()) 3558 return false; 3559 3560 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr); 3561 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3562 } 3563 3564 case BTT_IsTriviallyAssignable: { 3565 // C++11 [meta.unary.prop]p3: 3566 // is_trivially_assignable is defined as: 3567 // is_assignable<T, U>::value is true and the assignment, as defined by 3568 // is_assignable, is known to call no operation that is not trivial 3569 // 3570 // is_assignable is defined as: 3571 // The expression declval<T>() = declval<U>() is well-formed when 3572 // treated as an unevaluated operand (Clause 5). 3573 // 3574 // For both, T and U shall be complete types, (possibly cv-qualified) 3575 // void, or arrays of unknown bound. 3576 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() && 3577 Self.RequireCompleteType(KeyLoc, LhsT, 3578 diag::err_incomplete_type_used_in_type_trait_expr)) 3579 return false; 3580 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() && 3581 Self.RequireCompleteType(KeyLoc, RhsT, 3582 diag::err_incomplete_type_used_in_type_trait_expr)) 3583 return false; 3584 3585 // cv void is never assignable. 3586 if (LhsT->isVoidType() || RhsT->isVoidType()) 3587 return false; 3588 3589 // Build expressions that emulate the effect of declval<T>() and 3590 // declval<U>(). 3591 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3592 LhsT = Self.Context.getRValueReferenceType(LhsT); 3593 if (RhsT->isObjectType() || RhsT->isFunctionType()) 3594 RhsT = Self.Context.getRValueReferenceType(RhsT); 3595 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3596 Expr::getValueKindForType(LhsT)); 3597 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context), 3598 Expr::getValueKindForType(RhsT)); 3599 3600 // Attempt the assignment in an unevaluated context within a SFINAE 3601 // trap at translation unit scope. 3602 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3603 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3604 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3605 ExprResult Result = Self.BuildBinOp(/*S=*/0, KeyLoc, BO_Assign, &Lhs, &Rhs); 3606 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3607 return false; 3608 3609 // Under Objective-C ARC, if the destination has non-trivial Objective-C 3610 // lifetime, this is a non-trivial assignment. 3611 if (Self.getLangOpts().ObjCAutoRefCount && 3612 hasNontrivialObjCLifetime(LhsT.getNonReferenceType())) 3613 return false; 3614 3615 return !Result.get()->hasNonTrivialCall(Self.Context); 3616 } 3617 } 3618 llvm_unreachable("Unknown type trait or not implemented"); 3619} 3620 3621ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3622 SourceLocation KWLoc, 3623 TypeSourceInfo *LhsTSInfo, 3624 TypeSourceInfo *RhsTSInfo, 3625 SourceLocation RParen) { 3626 QualType LhsT = LhsTSInfo->getType(); 3627 QualType RhsT = RhsTSInfo->getType(); 3628 3629 if (BTT == BTT_TypeCompatible) { 3630 if (getLangOpts().CPlusPlus) { 3631 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3632 << SourceRange(KWLoc, RParen); 3633 return ExprError(); 3634 } 3635 } 3636 3637 bool Value = false; 3638 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3639 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3640 3641 // Select trait result type. 3642 QualType ResultType; 3643 switch (BTT) { 3644 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3645 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3646 case BTT_IsSame: ResultType = Context.BoolTy; break; 3647 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3648 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3649 case BTT_IsTriviallyAssignable: ResultType = Context.BoolTy; 3650 } 3651 3652 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3653 RhsTSInfo, Value, RParen, 3654 ResultType)); 3655} 3656 3657ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3658 SourceLocation KWLoc, 3659 ParsedType Ty, 3660 Expr* DimExpr, 3661 SourceLocation RParen) { 3662 TypeSourceInfo *TSInfo; 3663 QualType T = GetTypeFromParser(Ty, &TSInfo); 3664 if (!TSInfo) 3665 TSInfo = Context.getTrivialTypeSourceInfo(T); 3666 3667 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3668} 3669 3670static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3671 QualType T, Expr *DimExpr, 3672 SourceLocation KeyLoc) { 3673 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3674 3675 switch(ATT) { 3676 case ATT_ArrayRank: 3677 if (T->isArrayType()) { 3678 unsigned Dim = 0; 3679 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3680 ++Dim; 3681 T = AT->getElementType(); 3682 } 3683 return Dim; 3684 } 3685 return 0; 3686 3687 case ATT_ArrayExtent: { 3688 llvm::APSInt Value; 3689 uint64_t Dim; 3690 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3691 diag::err_dimension_expr_not_constant_integer, 3692 false).isInvalid()) 3693 return 0; 3694 if (Value.isSigned() && Value.isNegative()) { 3695 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer) 3696 << DimExpr->getSourceRange(); 3697 return 0; 3698 } 3699 Dim = Value.getLimitedValue(); 3700 3701 if (T->isArrayType()) { 3702 unsigned D = 0; 3703 bool Matched = false; 3704 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3705 if (Dim == D) { 3706 Matched = true; 3707 break; 3708 } 3709 ++D; 3710 T = AT->getElementType(); 3711 } 3712 3713 if (Matched && T->isArrayType()) { 3714 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3715 return CAT->getSize().getLimitedValue(); 3716 } 3717 } 3718 return 0; 3719 } 3720 } 3721 llvm_unreachable("Unknown type trait or not implemented"); 3722} 3723 3724ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3725 SourceLocation KWLoc, 3726 TypeSourceInfo *TSInfo, 3727 Expr* DimExpr, 3728 SourceLocation RParen) { 3729 QualType T = TSInfo->getType(); 3730 3731 // FIXME: This should likely be tracked as an APInt to remove any host 3732 // assumptions about the width of size_t on the target. 3733 uint64_t Value = 0; 3734 if (!T->isDependentType()) 3735 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3736 3737 // While the specification for these traits from the Embarcadero C++ 3738 // compiler's documentation says the return type is 'unsigned int', Clang 3739 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3740 // compiler, there is no difference. On several other platforms this is an 3741 // important distinction. 3742 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3743 DimExpr, RParen, 3744 Context.getSizeType())); 3745} 3746 3747ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3748 SourceLocation KWLoc, 3749 Expr *Queried, 3750 SourceLocation RParen) { 3751 // If error parsing the expression, ignore. 3752 if (!Queried) 3753 return ExprError(); 3754 3755 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3756 3757 return Result; 3758} 3759 3760static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3761 switch (ET) { 3762 case ET_IsLValueExpr: return E->isLValue(); 3763 case ET_IsRValueExpr: return E->isRValue(); 3764 } 3765 llvm_unreachable("Expression trait not covered by switch"); 3766} 3767 3768ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3769 SourceLocation KWLoc, 3770 Expr *Queried, 3771 SourceLocation RParen) { 3772 if (Queried->isTypeDependent()) { 3773 // Delay type-checking for type-dependent expressions. 3774 } else if (Queried->getType()->isPlaceholderType()) { 3775 ExprResult PE = CheckPlaceholderExpr(Queried); 3776 if (PE.isInvalid()) return ExprError(); 3777 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3778 } 3779 3780 bool Value = EvaluateExpressionTrait(ET, Queried); 3781 3782 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3783 RParen, Context.BoolTy)); 3784} 3785 3786QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3787 ExprValueKind &VK, 3788 SourceLocation Loc, 3789 bool isIndirect) { 3790 assert(!LHS.get()->getType()->isPlaceholderType() && 3791 !RHS.get()->getType()->isPlaceholderType() && 3792 "placeholders should have been weeded out by now"); 3793 3794 // The LHS undergoes lvalue conversions if this is ->*. 3795 if (isIndirect) { 3796 LHS = DefaultLvalueConversion(LHS.take()); 3797 if (LHS.isInvalid()) return QualType(); 3798 } 3799 3800 // The RHS always undergoes lvalue conversions. 3801 RHS = DefaultLvalueConversion(RHS.take()); 3802 if (RHS.isInvalid()) return QualType(); 3803 3804 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3805 // C++ 5.5p2 3806 // The binary operator .* [p3: ->*] binds its second operand, which shall 3807 // be of type "pointer to member of T" (where T is a completely-defined 3808 // class type) [...] 3809 QualType RHSType = RHS.get()->getType(); 3810 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3811 if (!MemPtr) { 3812 Diag(Loc, diag::err_bad_memptr_rhs) 3813 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3814 return QualType(); 3815 } 3816 3817 QualType Class(MemPtr->getClass(), 0); 3818 3819 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3820 // member pointer points must be completely-defined. However, there is no 3821 // reason for this semantic distinction, and the rule is not enforced by 3822 // other compilers. Therefore, we do not check this property, as it is 3823 // likely to be considered a defect. 3824 3825 // C++ 5.5p2 3826 // [...] to its first operand, which shall be of class T or of a class of 3827 // which T is an unambiguous and accessible base class. [p3: a pointer to 3828 // such a class] 3829 QualType LHSType = LHS.get()->getType(); 3830 if (isIndirect) { 3831 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3832 LHSType = Ptr->getPointeeType(); 3833 else { 3834 Diag(Loc, diag::err_bad_memptr_lhs) 3835 << OpSpelling << 1 << LHSType 3836 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3837 return QualType(); 3838 } 3839 } 3840 3841 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3842 // If we want to check the hierarchy, we need a complete type. 3843 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs, 3844 OpSpelling, (int)isIndirect)) { 3845 return QualType(); 3846 } 3847 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3848 /*DetectVirtual=*/false); 3849 // FIXME: Would it be useful to print full ambiguity paths, or is that 3850 // overkill? 3851 if (!IsDerivedFrom(LHSType, Class, Paths) || 3852 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3853 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3854 << (int)isIndirect << LHS.get()->getType(); 3855 return QualType(); 3856 } 3857 // Cast LHS to type of use. 3858 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3859 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3860 3861 CXXCastPath BasePath; 3862 BuildBasePathArray(Paths, BasePath); 3863 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3864 &BasePath); 3865 } 3866 3867 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3868 // Diagnose use of pointer-to-member type which when used as 3869 // the functional cast in a pointer-to-member expression. 3870 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3871 return QualType(); 3872 } 3873 3874 // C++ 5.5p2 3875 // The result is an object or a function of the type specified by the 3876 // second operand. 3877 // The cv qualifiers are the union of those in the pointer and the left side, 3878 // in accordance with 5.5p5 and 5.2.5. 3879 QualType Result = MemPtr->getPointeeType(); 3880 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3881 3882 // C++0x [expr.mptr.oper]p6: 3883 // In a .* expression whose object expression is an rvalue, the program is 3884 // ill-formed if the second operand is a pointer to member function with 3885 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3886 // expression is an lvalue, the program is ill-formed if the second operand 3887 // is a pointer to member function with ref-qualifier &&. 3888 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3889 switch (Proto->getRefQualifier()) { 3890 case RQ_None: 3891 // Do nothing 3892 break; 3893 3894 case RQ_LValue: 3895 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3896 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3897 << RHSType << 1 << LHS.get()->getSourceRange(); 3898 break; 3899 3900 case RQ_RValue: 3901 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 3902 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3903 << RHSType << 0 << LHS.get()->getSourceRange(); 3904 break; 3905 } 3906 } 3907 3908 // C++ [expr.mptr.oper]p6: 3909 // The result of a .* expression whose second operand is a pointer 3910 // to a data member is of the same value category as its 3911 // first operand. The result of a .* expression whose second 3912 // operand is a pointer to a member function is a prvalue. The 3913 // result of an ->* expression is an lvalue if its second operand 3914 // is a pointer to data member and a prvalue otherwise. 3915 if (Result->isFunctionType()) { 3916 VK = VK_RValue; 3917 return Context.BoundMemberTy; 3918 } else if (isIndirect) { 3919 VK = VK_LValue; 3920 } else { 3921 VK = LHS.get()->getValueKind(); 3922 } 3923 3924 return Result; 3925} 3926 3927/// \brief Try to convert a type to another according to C++0x 5.16p3. 3928/// 3929/// This is part of the parameter validation for the ? operator. If either 3930/// value operand is a class type, the two operands are attempted to be 3931/// converted to each other. This function does the conversion in one direction. 3932/// It returns true if the program is ill-formed and has already been diagnosed 3933/// as such. 3934static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 3935 SourceLocation QuestionLoc, 3936 bool &HaveConversion, 3937 QualType &ToType) { 3938 HaveConversion = false; 3939 ToType = To->getType(); 3940 3941 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 3942 SourceLocation()); 3943 // C++0x 5.16p3 3944 // The process for determining whether an operand expression E1 of type T1 3945 // can be converted to match an operand expression E2 of type T2 is defined 3946 // as follows: 3947 // -- If E2 is an lvalue: 3948 bool ToIsLvalue = To->isLValue(); 3949 if (ToIsLvalue) { 3950 // E1 can be converted to match E2 if E1 can be implicitly converted to 3951 // type "lvalue reference to T2", subject to the constraint that in the 3952 // conversion the reference must bind directly to E1. 3953 QualType T = Self.Context.getLValueReferenceType(ToType); 3954 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3955 3956 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3957 if (InitSeq.isDirectReferenceBinding()) { 3958 ToType = T; 3959 HaveConversion = true; 3960 return false; 3961 } 3962 3963 if (InitSeq.isAmbiguous()) 3964 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3965 } 3966 3967 // -- If E2 is an rvalue, or if the conversion above cannot be done: 3968 // -- if E1 and E2 have class type, and the underlying class types are 3969 // the same or one is a base class of the other: 3970 QualType FTy = From->getType(); 3971 QualType TTy = To->getType(); 3972 const RecordType *FRec = FTy->getAs<RecordType>(); 3973 const RecordType *TRec = TTy->getAs<RecordType>(); 3974 bool FDerivedFromT = FRec && TRec && FRec != TRec && 3975 Self.IsDerivedFrom(FTy, TTy); 3976 if (FRec && TRec && 3977 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 3978 // E1 can be converted to match E2 if the class of T2 is the 3979 // same type as, or a base class of, the class of T1, and 3980 // [cv2 > cv1]. 3981 if (FRec == TRec || FDerivedFromT) { 3982 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 3983 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3984 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3985 if (InitSeq) { 3986 HaveConversion = true; 3987 return false; 3988 } 3989 3990 if (InitSeq.isAmbiguous()) 3991 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3992 } 3993 } 3994 3995 return false; 3996 } 3997 3998 // -- Otherwise: E1 can be converted to match E2 if E1 can be 3999 // implicitly converted to the type that expression E2 would have 4000 // if E2 were converted to an rvalue (or the type it has, if E2 is 4001 // an rvalue). 4002 // 4003 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 4004 // to the array-to-pointer or function-to-pointer conversions. 4005 if (!TTy->getAs<TagType>()) 4006 TTy = TTy.getUnqualifiedType(); 4007 4008 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 4009 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 4010 HaveConversion = !InitSeq.Failed(); 4011 ToType = TTy; 4012 if (InitSeq.isAmbiguous()) 4013 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 4014 4015 return false; 4016} 4017 4018/// \brief Try to find a common type for two according to C++0x 5.16p5. 4019/// 4020/// This is part of the parameter validation for the ? operator. If either 4021/// value operand is a class type, overload resolution is used to find a 4022/// conversion to a common type. 4023static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 4024 SourceLocation QuestionLoc) { 4025 Expr *Args[2] = { LHS.get(), RHS.get() }; 4026 OverloadCandidateSet CandidateSet(QuestionLoc); 4027 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 2, 4028 CandidateSet); 4029 4030 OverloadCandidateSet::iterator Best; 4031 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 4032 case OR_Success: { 4033 // We found a match. Perform the conversions on the arguments and move on. 4034 ExprResult LHSRes = 4035 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 4036 Best->Conversions[0], Sema::AA_Converting); 4037 if (LHSRes.isInvalid()) 4038 break; 4039 LHS = LHSRes; 4040 4041 ExprResult RHSRes = 4042 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 4043 Best->Conversions[1], Sema::AA_Converting); 4044 if (RHSRes.isInvalid()) 4045 break; 4046 RHS = RHSRes; 4047 if (Best->Function) 4048 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 4049 return false; 4050 } 4051 4052 case OR_No_Viable_Function: 4053 4054 // Emit a better diagnostic if one of the expressions is a null pointer 4055 // constant and the other is a pointer type. In this case, the user most 4056 // likely forgot to take the address of the other expression. 4057 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4058 return true; 4059 4060 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4061 << LHS.get()->getType() << RHS.get()->getType() 4062 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4063 return true; 4064 4065 case OR_Ambiguous: 4066 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 4067 << LHS.get()->getType() << RHS.get()->getType() 4068 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4069 // FIXME: Print the possible common types by printing the return types of 4070 // the viable candidates. 4071 break; 4072 4073 case OR_Deleted: 4074 llvm_unreachable("Conditional operator has only built-in overloads"); 4075 } 4076 return true; 4077} 4078 4079/// \brief Perform an "extended" implicit conversion as returned by 4080/// TryClassUnification. 4081static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 4082 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 4083 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 4084 SourceLocation()); 4085 Expr *Arg = E.take(); 4086 InitializationSequence InitSeq(Self, Entity, Kind, &Arg, 1); 4087 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg); 4088 if (Result.isInvalid()) 4089 return true; 4090 4091 E = Result; 4092 return false; 4093} 4094 4095/// \brief Check the operands of ?: under C++ semantics. 4096/// 4097/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 4098/// extension. In this case, LHS == Cond. (But they're not aliases.) 4099QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 4100 ExprResult &RHS, ExprValueKind &VK, 4101 ExprObjectKind &OK, 4102 SourceLocation QuestionLoc) { 4103 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 4104 // interface pointers. 4105 4106 // C++11 [expr.cond]p1 4107 // The first expression is contextually converted to bool. 4108 if (!Cond.get()->isTypeDependent()) { 4109 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 4110 if (CondRes.isInvalid()) 4111 return QualType(); 4112 Cond = CondRes; 4113 } 4114 4115 // Assume r-value. 4116 VK = VK_RValue; 4117 OK = OK_Ordinary; 4118 4119 // Either of the arguments dependent? 4120 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 4121 return Context.DependentTy; 4122 4123 // C++11 [expr.cond]p2 4124 // If either the second or the third operand has type (cv) void, ... 4125 QualType LTy = LHS.get()->getType(); 4126 QualType RTy = RHS.get()->getType(); 4127 bool LVoid = LTy->isVoidType(); 4128 bool RVoid = RTy->isVoidType(); 4129 if (LVoid || RVoid) { 4130 // ... then the [l2r] conversions are performed on the second and third 4131 // operands ... 4132 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4133 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4134 if (LHS.isInvalid() || RHS.isInvalid()) 4135 return QualType(); 4136 4137 // Finish off the lvalue-to-rvalue conversion by copy-initializing a 4138 // temporary if necessary. DefaultFunctionArrayLvalueConversion doesn't 4139 // do this part for us. 4140 ExprResult &NonVoid = LVoid ? RHS : LHS; 4141 if (NonVoid.get()->getType()->isRecordType() && 4142 NonVoid.get()->isGLValue()) { 4143 if (RequireNonAbstractType(QuestionLoc, NonVoid.get()->getType(), 4144 diag::err_allocation_of_abstract_type)) 4145 return QualType(); 4146 InitializedEntity Entity = 4147 InitializedEntity::InitializeTemporary(NonVoid.get()->getType()); 4148 NonVoid = PerformCopyInitialization(Entity, SourceLocation(), NonVoid); 4149 if (NonVoid.isInvalid()) 4150 return QualType(); 4151 } 4152 4153 LTy = LHS.get()->getType(); 4154 RTy = RHS.get()->getType(); 4155 4156 // ... and one of the following shall hold: 4157 // -- The second or the third operand (but not both) is a throw- 4158 // expression; the result is of the type of the other and is a prvalue. 4159 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 4160 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 4161 if (LThrow && !RThrow) 4162 return RTy; 4163 if (RThrow && !LThrow) 4164 return LTy; 4165 4166 // -- Both the second and third operands have type void; the result is of 4167 // type void and is a prvalue. 4168 if (LVoid && RVoid) 4169 return Context.VoidTy; 4170 4171 // Neither holds, error. 4172 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 4173 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 4174 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4175 return QualType(); 4176 } 4177 4178 // Neither is void. 4179 4180 // C++11 [expr.cond]p3 4181 // Otherwise, if the second and third operand have different types, and 4182 // either has (cv) class type [...] an attempt is made to convert each of 4183 // those operands to the type of the other. 4184 if (!Context.hasSameType(LTy, RTy) && 4185 (LTy->isRecordType() || RTy->isRecordType())) { 4186 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 4187 // These return true if a single direction is already ambiguous. 4188 QualType L2RType, R2LType; 4189 bool HaveL2R, HaveR2L; 4190 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 4191 return QualType(); 4192 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 4193 return QualType(); 4194 4195 // If both can be converted, [...] the program is ill-formed. 4196 if (HaveL2R && HaveR2L) { 4197 Diag(QuestionLoc, diag::err_conditional_ambiguous) 4198 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4199 return QualType(); 4200 } 4201 4202 // If exactly one conversion is possible, that conversion is applied to 4203 // the chosen operand and the converted operands are used in place of the 4204 // original operands for the remainder of this section. 4205 if (HaveL2R) { 4206 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 4207 return QualType(); 4208 LTy = LHS.get()->getType(); 4209 } else if (HaveR2L) { 4210 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 4211 return QualType(); 4212 RTy = RHS.get()->getType(); 4213 } 4214 } 4215 4216 // C++11 [expr.cond]p3 4217 // if both are glvalues of the same value category and the same type except 4218 // for cv-qualification, an attempt is made to convert each of those 4219 // operands to the type of the other. 4220 ExprValueKind LVK = LHS.get()->getValueKind(); 4221 ExprValueKind RVK = RHS.get()->getValueKind(); 4222 if (!Context.hasSameType(LTy, RTy) && 4223 Context.hasSameUnqualifiedType(LTy, RTy) && 4224 LVK == RVK && LVK != VK_RValue) { 4225 // Since the unqualified types are reference-related and we require the 4226 // result to be as if a reference bound directly, the only conversion 4227 // we can perform is to add cv-qualifiers. 4228 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers()); 4229 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers()); 4230 if (RCVR.isStrictSupersetOf(LCVR)) { 4231 LHS = ImpCastExprToType(LHS.take(), RTy, CK_NoOp, LVK); 4232 LTy = LHS.get()->getType(); 4233 } 4234 else if (LCVR.isStrictSupersetOf(RCVR)) { 4235 RHS = ImpCastExprToType(RHS.take(), LTy, CK_NoOp, RVK); 4236 RTy = RHS.get()->getType(); 4237 } 4238 } 4239 4240 // C++11 [expr.cond]p4 4241 // If the second and third operands are glvalues of the same value 4242 // category and have the same type, the result is of that type and 4243 // value category and it is a bit-field if the second or the third 4244 // operand is a bit-field, or if both are bit-fields. 4245 // We only extend this to bitfields, not to the crazy other kinds of 4246 // l-values. 4247 bool Same = Context.hasSameType(LTy, RTy); 4248 if (Same && LVK == RVK && LVK != VK_RValue && 4249 LHS.get()->isOrdinaryOrBitFieldObject() && 4250 RHS.get()->isOrdinaryOrBitFieldObject()) { 4251 VK = LHS.get()->getValueKind(); 4252 if (LHS.get()->getObjectKind() == OK_BitField || 4253 RHS.get()->getObjectKind() == OK_BitField) 4254 OK = OK_BitField; 4255 return LTy; 4256 } 4257 4258 // C++11 [expr.cond]p5 4259 // Otherwise, the result is a prvalue. If the second and third operands 4260 // do not have the same type, and either has (cv) class type, ... 4261 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 4262 // ... overload resolution is used to determine the conversions (if any) 4263 // to be applied to the operands. If the overload resolution fails, the 4264 // program is ill-formed. 4265 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 4266 return QualType(); 4267 } 4268 4269 // C++11 [expr.cond]p6 4270 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard 4271 // conversions are performed on the second and third operands. 4272 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4273 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4274 if (LHS.isInvalid() || RHS.isInvalid()) 4275 return QualType(); 4276 LTy = LHS.get()->getType(); 4277 RTy = RHS.get()->getType(); 4278 4279 // After those conversions, one of the following shall hold: 4280 // -- The second and third operands have the same type; the result 4281 // is of that type. If the operands have class type, the result 4282 // is a prvalue temporary of the result type, which is 4283 // copy-initialized from either the second operand or the third 4284 // operand depending on the value of the first operand. 4285 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 4286 if (LTy->isRecordType()) { 4287 // The operands have class type. Make a temporary copy. 4288 if (RequireNonAbstractType(QuestionLoc, LTy, 4289 diag::err_allocation_of_abstract_type)) 4290 return QualType(); 4291 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 4292 4293 ExprResult LHSCopy = PerformCopyInitialization(Entity, 4294 SourceLocation(), 4295 LHS); 4296 if (LHSCopy.isInvalid()) 4297 return QualType(); 4298 4299 ExprResult RHSCopy = PerformCopyInitialization(Entity, 4300 SourceLocation(), 4301 RHS); 4302 if (RHSCopy.isInvalid()) 4303 return QualType(); 4304 4305 LHS = LHSCopy; 4306 RHS = RHSCopy; 4307 } 4308 4309 return LTy; 4310 } 4311 4312 // Extension: conditional operator involving vector types. 4313 if (LTy->isVectorType() || RTy->isVectorType()) 4314 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4315 4316 // -- The second and third operands have arithmetic or enumeration type; 4317 // the usual arithmetic conversions are performed to bring them to a 4318 // common type, and the result is of that type. 4319 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 4320 UsualArithmeticConversions(LHS, RHS); 4321 if (LHS.isInvalid() || RHS.isInvalid()) 4322 return QualType(); 4323 return LHS.get()->getType(); 4324 } 4325 4326 // -- The second and third operands have pointer type, or one has pointer 4327 // type and the other is a null pointer constant, or both are null 4328 // pointer constants, at least one of which is non-integral; pointer 4329 // conversions and qualification conversions are performed to bring them 4330 // to their composite pointer type. The result is of the composite 4331 // pointer type. 4332 // -- The second and third operands have pointer to member type, or one has 4333 // pointer to member type and the other is a null pointer constant; 4334 // pointer to member conversions and qualification conversions are 4335 // performed to bring them to a common type, whose cv-qualification 4336 // shall match the cv-qualification of either the second or the third 4337 // operand. The result is of the common type. 4338 bool NonStandardCompositeType = false; 4339 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 4340 isSFINAEContext()? 0 : &NonStandardCompositeType); 4341 if (!Composite.isNull()) { 4342 if (NonStandardCompositeType) 4343 Diag(QuestionLoc, 4344 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 4345 << LTy << RTy << Composite 4346 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4347 4348 return Composite; 4349 } 4350 4351 // Similarly, attempt to find composite type of two objective-c pointers. 4352 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 4353 if (!Composite.isNull()) 4354 return Composite; 4355 4356 // Check if we are using a null with a non-pointer type. 4357 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4358 return QualType(); 4359 4360 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4361 << LHS.get()->getType() << RHS.get()->getType() 4362 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4363 return QualType(); 4364} 4365 4366/// \brief Find a merged pointer type and convert the two expressions to it. 4367/// 4368/// This finds the composite pointer type (or member pointer type) for @p E1 4369/// and @p E2 according to C++11 5.9p2. It converts both expressions to this 4370/// type and returns it. 4371/// It does not emit diagnostics. 4372/// 4373/// \param Loc The location of the operator requiring these two expressions to 4374/// be converted to the composite pointer type. 4375/// 4376/// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4377/// a non-standard (but still sane) composite type to which both expressions 4378/// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4379/// will be set true. 4380QualType Sema::FindCompositePointerType(SourceLocation Loc, 4381 Expr *&E1, Expr *&E2, 4382 bool *NonStandardCompositeType) { 4383 if (NonStandardCompositeType) 4384 *NonStandardCompositeType = false; 4385 4386 assert(getLangOpts().CPlusPlus && "This function assumes C++"); 4387 QualType T1 = E1->getType(), T2 = E2->getType(); 4388 4389 // C++11 5.9p2 4390 // Pointer conversions and qualification conversions are performed on 4391 // pointer operands to bring them to their composite pointer type. If 4392 // one operand is a null pointer constant, the composite pointer type is 4393 // std::nullptr_t if the other operand is also a null pointer constant or, 4394 // if the other operand is a pointer, the type of the other operand. 4395 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4396 !T2->isAnyPointerType() && !T2->isMemberPointerType()) { 4397 if (T1->isNullPtrType() && 4398 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4399 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4400 return T1; 4401 } 4402 if (T2->isNullPtrType() && 4403 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4404 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4405 return T2; 4406 } 4407 return QualType(); 4408 } 4409 4410 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4411 if (T2->isMemberPointerType()) 4412 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4413 else 4414 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4415 return T2; 4416 } 4417 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4418 if (T1->isMemberPointerType()) 4419 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4420 else 4421 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4422 return T1; 4423 } 4424 4425 // Now both have to be pointers or member pointers. 4426 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4427 (!T2->isPointerType() && !T2->isMemberPointerType())) 4428 return QualType(); 4429 4430 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4431 // the other has type "pointer to cv2 T" and the composite pointer type is 4432 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4433 // Otherwise, the composite pointer type is a pointer type similar to the 4434 // type of one of the operands, with a cv-qualification signature that is 4435 // the union of the cv-qualification signatures of the operand types. 4436 // In practice, the first part here is redundant; it's subsumed by the second. 4437 // What we do here is, we build the two possible composite types, and try the 4438 // conversions in both directions. If only one works, or if the two composite 4439 // types are the same, we have succeeded. 4440 // FIXME: extended qualifiers? 4441 typedef SmallVector<unsigned, 4> QualifierVector; 4442 QualifierVector QualifierUnion; 4443 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4444 ContainingClassVector; 4445 ContainingClassVector MemberOfClass; 4446 QualType Composite1 = Context.getCanonicalType(T1), 4447 Composite2 = Context.getCanonicalType(T2); 4448 unsigned NeedConstBefore = 0; 4449 do { 4450 const PointerType *Ptr1, *Ptr2; 4451 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4452 (Ptr2 = Composite2->getAs<PointerType>())) { 4453 Composite1 = Ptr1->getPointeeType(); 4454 Composite2 = Ptr2->getPointeeType(); 4455 4456 // If we're allowed to create a non-standard composite type, keep track 4457 // of where we need to fill in additional 'const' qualifiers. 4458 if (NonStandardCompositeType && 4459 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4460 NeedConstBefore = QualifierUnion.size(); 4461 4462 QualifierUnion.push_back( 4463 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4464 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4465 continue; 4466 } 4467 4468 const MemberPointerType *MemPtr1, *MemPtr2; 4469 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4470 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4471 Composite1 = MemPtr1->getPointeeType(); 4472 Composite2 = MemPtr2->getPointeeType(); 4473 4474 // If we're allowed to create a non-standard composite type, keep track 4475 // of where we need to fill in additional 'const' qualifiers. 4476 if (NonStandardCompositeType && 4477 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4478 NeedConstBefore = QualifierUnion.size(); 4479 4480 QualifierUnion.push_back( 4481 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4482 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4483 MemPtr2->getClass())); 4484 continue; 4485 } 4486 4487 // FIXME: block pointer types? 4488 4489 // Cannot unwrap any more types. 4490 break; 4491 } while (true); 4492 4493 if (NeedConstBefore && NonStandardCompositeType) { 4494 // Extension: Add 'const' to qualifiers that come before the first qualifier 4495 // mismatch, so that our (non-standard!) composite type meets the 4496 // requirements of C++ [conv.qual]p4 bullet 3. 4497 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4498 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4499 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4500 *NonStandardCompositeType = true; 4501 } 4502 } 4503 } 4504 4505 // Rewrap the composites as pointers or member pointers with the union CVRs. 4506 ContainingClassVector::reverse_iterator MOC 4507 = MemberOfClass.rbegin(); 4508 for (QualifierVector::reverse_iterator 4509 I = QualifierUnion.rbegin(), 4510 E = QualifierUnion.rend(); 4511 I != E; (void)++I, ++MOC) { 4512 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4513 if (MOC->first && MOC->second) { 4514 // Rebuild member pointer type 4515 Composite1 = Context.getMemberPointerType( 4516 Context.getQualifiedType(Composite1, Quals), 4517 MOC->first); 4518 Composite2 = Context.getMemberPointerType( 4519 Context.getQualifiedType(Composite2, Quals), 4520 MOC->second); 4521 } else { 4522 // Rebuild pointer type 4523 Composite1 4524 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4525 Composite2 4526 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4527 } 4528 } 4529 4530 // Try to convert to the first composite pointer type. 4531 InitializedEntity Entity1 4532 = InitializedEntity::InitializeTemporary(Composite1); 4533 InitializationKind Kind 4534 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4535 InitializationSequence E1ToC1(*this, Entity1, Kind, &E1, 1); 4536 InitializationSequence E2ToC1(*this, Entity1, Kind, &E2, 1); 4537 4538 if (E1ToC1 && E2ToC1) { 4539 // Conversion to Composite1 is viable. 4540 if (!Context.hasSameType(Composite1, Composite2)) { 4541 // Composite2 is a different type from Composite1. Check whether 4542 // Composite2 is also viable. 4543 InitializedEntity Entity2 4544 = InitializedEntity::InitializeTemporary(Composite2); 4545 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4546 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4547 if (E1ToC2 && E2ToC2) { 4548 // Both Composite1 and Composite2 are viable and are different; 4549 // this is an ambiguity. 4550 return QualType(); 4551 } 4552 } 4553 4554 // Convert E1 to Composite1 4555 ExprResult E1Result 4556 = E1ToC1.Perform(*this, Entity1, Kind, E1); 4557 if (E1Result.isInvalid()) 4558 return QualType(); 4559 E1 = E1Result.takeAs<Expr>(); 4560 4561 // Convert E2 to Composite1 4562 ExprResult E2Result 4563 = E2ToC1.Perform(*this, Entity1, Kind, E2); 4564 if (E2Result.isInvalid()) 4565 return QualType(); 4566 E2 = E2Result.takeAs<Expr>(); 4567 4568 return Composite1; 4569 } 4570 4571 // Check whether Composite2 is viable. 4572 InitializedEntity Entity2 4573 = InitializedEntity::InitializeTemporary(Composite2); 4574 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4575 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4576 if (!E1ToC2 || !E2ToC2) 4577 return QualType(); 4578 4579 // Convert E1 to Composite2 4580 ExprResult E1Result 4581 = E1ToC2.Perform(*this, Entity2, Kind, E1); 4582 if (E1Result.isInvalid()) 4583 return QualType(); 4584 E1 = E1Result.takeAs<Expr>(); 4585 4586 // Convert E2 to Composite2 4587 ExprResult E2Result 4588 = E2ToC2.Perform(*this, Entity2, Kind, E2); 4589 if (E2Result.isInvalid()) 4590 return QualType(); 4591 E2 = E2Result.takeAs<Expr>(); 4592 4593 return Composite2; 4594} 4595 4596ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4597 if (!E) 4598 return ExprError(); 4599 4600 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4601 4602 // If the result is a glvalue, we shouldn't bind it. 4603 if (!E->isRValue()) 4604 return Owned(E); 4605 4606 // In ARC, calls that return a retainable type can return retained, 4607 // in which case we have to insert a consuming cast. 4608 if (getLangOpts().ObjCAutoRefCount && 4609 E->getType()->isObjCRetainableType()) { 4610 4611 bool ReturnsRetained; 4612 4613 // For actual calls, we compute this by examining the type of the 4614 // called value. 4615 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4616 Expr *Callee = Call->getCallee()->IgnoreParens(); 4617 QualType T = Callee->getType(); 4618 4619 if (T == Context.BoundMemberTy) { 4620 // Handle pointer-to-members. 4621 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4622 T = BinOp->getRHS()->getType(); 4623 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4624 T = Mem->getMemberDecl()->getType(); 4625 } 4626 4627 if (const PointerType *Ptr = T->getAs<PointerType>()) 4628 T = Ptr->getPointeeType(); 4629 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4630 T = Ptr->getPointeeType(); 4631 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4632 T = MemPtr->getPointeeType(); 4633 4634 const FunctionType *FTy = T->getAs<FunctionType>(); 4635 assert(FTy && "call to value not of function type?"); 4636 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4637 4638 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4639 // type always produce a +1 object. 4640 } else if (isa<StmtExpr>(E)) { 4641 ReturnsRetained = true; 4642 4643 // We hit this case with the lambda conversion-to-block optimization; 4644 // we don't want any extra casts here. 4645 } else if (isa<CastExpr>(E) && 4646 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) { 4647 return Owned(E); 4648 4649 // For message sends and property references, we try to find an 4650 // actual method. FIXME: we should infer retention by selector in 4651 // cases where we don't have an actual method. 4652 } else { 4653 ObjCMethodDecl *D = 0; 4654 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4655 D = Send->getMethodDecl(); 4656 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) { 4657 D = BoxedExpr->getBoxingMethod(); 4658 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) { 4659 D = ArrayLit->getArrayWithObjectsMethod(); 4660 } else if (ObjCDictionaryLiteral *DictLit 4661 = dyn_cast<ObjCDictionaryLiteral>(E)) { 4662 D = DictLit->getDictWithObjectsMethod(); 4663 } 4664 4665 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4666 4667 // Don't do reclaims on performSelector calls; despite their 4668 // return type, the invoked method doesn't necessarily actually 4669 // return an object. 4670 if (!ReturnsRetained && 4671 D && D->getMethodFamily() == OMF_performSelector) 4672 return Owned(E); 4673 } 4674 4675 // Don't reclaim an object of Class type. 4676 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4677 return Owned(E); 4678 4679 ExprNeedsCleanups = true; 4680 4681 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4682 : CK_ARCReclaimReturnedObject); 4683 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4684 VK_RValue)); 4685 } 4686 4687 if (!getLangOpts().CPlusPlus) 4688 return Owned(E); 4689 4690 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4691 // a fast path for the common case that the type is directly a RecordType. 4692 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4693 const RecordType *RT = 0; 4694 while (!RT) { 4695 switch (T->getTypeClass()) { 4696 case Type::Record: 4697 RT = cast<RecordType>(T); 4698 break; 4699 case Type::ConstantArray: 4700 case Type::IncompleteArray: 4701 case Type::VariableArray: 4702 case Type::DependentSizedArray: 4703 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4704 break; 4705 default: 4706 return Owned(E); 4707 } 4708 } 4709 4710 // That should be enough to guarantee that this type is complete, if we're 4711 // not processing a decltype expression. 4712 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4713 if (RD->isInvalidDecl() || RD->isDependentContext()) 4714 return Owned(E); 4715 4716 bool IsDecltype = ExprEvalContexts.back().IsDecltype; 4717 CXXDestructorDecl *Destructor = IsDecltype ? 0 : LookupDestructor(RD); 4718 4719 if (Destructor) { 4720 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4721 CheckDestructorAccess(E->getExprLoc(), Destructor, 4722 PDiag(diag::err_access_dtor_temp) 4723 << E->getType()); 4724 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 4725 4726 // If destructor is trivial, we can avoid the extra copy. 4727 if (Destructor->isTrivial()) 4728 return Owned(E); 4729 4730 // We need a cleanup, but we don't need to remember the temporary. 4731 ExprNeedsCleanups = true; 4732 } 4733 4734 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4735 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E); 4736 4737 if (IsDecltype) 4738 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind); 4739 4740 return Owned(Bind); 4741} 4742 4743ExprResult 4744Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4745 if (SubExpr.isInvalid()) 4746 return ExprError(); 4747 4748 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4749} 4750 4751Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4752 assert(SubExpr && "sub expression can't be null!"); 4753 4754 CleanupVarDeclMarking(); 4755 4756 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4757 assert(ExprCleanupObjects.size() >= FirstCleanup); 4758 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4759 if (!ExprNeedsCleanups) 4760 return SubExpr; 4761 4762 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4763 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4764 ExprCleanupObjects.size() - FirstCleanup); 4765 4766 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4767 DiscardCleanupsInEvaluationContext(); 4768 4769 return E; 4770} 4771 4772Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4773 assert(SubStmt && "sub statement can't be null!"); 4774 4775 CleanupVarDeclMarking(); 4776 4777 if (!ExprNeedsCleanups) 4778 return SubStmt; 4779 4780 // FIXME: In order to attach the temporaries, wrap the statement into 4781 // a StmtExpr; currently this is only used for asm statements. 4782 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4783 // a new AsmStmtWithTemporaries. 4784 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt, 4785 SourceLocation(), 4786 SourceLocation()); 4787 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4788 SourceLocation()); 4789 return MaybeCreateExprWithCleanups(E); 4790} 4791 4792/// Process the expression contained within a decltype. For such expressions, 4793/// certain semantic checks on temporaries are delayed until this point, and 4794/// are omitted for the 'topmost' call in the decltype expression. If the 4795/// topmost call bound a temporary, strip that temporary off the expression. 4796ExprResult Sema::ActOnDecltypeExpression(Expr *E) { 4797 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression"); 4798 4799 // C++11 [expr.call]p11: 4800 // If a function call is a prvalue of object type, 4801 // -- if the function call is either 4802 // -- the operand of a decltype-specifier, or 4803 // -- the right operand of a comma operator that is the operand of a 4804 // decltype-specifier, 4805 // a temporary object is not introduced for the prvalue. 4806 4807 // Recursively rebuild ParenExprs and comma expressions to strip out the 4808 // outermost CXXBindTemporaryExpr, if any. 4809 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 4810 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr()); 4811 if (SubExpr.isInvalid()) 4812 return ExprError(); 4813 if (SubExpr.get() == PE->getSubExpr()) 4814 return Owned(E); 4815 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.take()); 4816 } 4817 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 4818 if (BO->getOpcode() == BO_Comma) { 4819 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS()); 4820 if (RHS.isInvalid()) 4821 return ExprError(); 4822 if (RHS.get() == BO->getRHS()) 4823 return Owned(E); 4824 return Owned(new (Context) BinaryOperator(BO->getLHS(), RHS.take(), 4825 BO_Comma, BO->getType(), 4826 BO->getValueKind(), 4827 BO->getObjectKind(), 4828 BO->getOperatorLoc(), 4829 BO->isFPContractable())); 4830 } 4831 } 4832 4833 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E); 4834 if (TopBind) 4835 E = TopBind->getSubExpr(); 4836 4837 // Disable the special decltype handling now. 4838 ExprEvalContexts.back().IsDecltype = false; 4839 4840 // In MS mode, don't perform any extra checking of call return types within a 4841 // decltype expression. 4842 if (getLangOpts().MicrosoftMode) 4843 return Owned(E); 4844 4845 // Perform the semantic checks we delayed until this point. 4846 CallExpr *TopCall = dyn_cast<CallExpr>(E); 4847 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size(); 4848 I != N; ++I) { 4849 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I]; 4850 if (Call == TopCall) 4851 continue; 4852 4853 if (CheckCallReturnType(Call->getCallReturnType(), 4854 Call->getLocStart(), 4855 Call, Call->getDirectCallee())) 4856 return ExprError(); 4857 } 4858 4859 // Now all relevant types are complete, check the destructors are accessible 4860 // and non-deleted, and annotate them on the temporaries. 4861 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size(); 4862 I != N; ++I) { 4863 CXXBindTemporaryExpr *Bind = 4864 ExprEvalContexts.back().DelayedDecltypeBinds[I]; 4865 if (Bind == TopBind) 4866 continue; 4867 4868 CXXTemporary *Temp = Bind->getTemporary(); 4869 4870 CXXRecordDecl *RD = 4871 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 4872 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4873 Temp->setDestructor(Destructor); 4874 4875 MarkFunctionReferenced(Bind->getExprLoc(), Destructor); 4876 CheckDestructorAccess(Bind->getExprLoc(), Destructor, 4877 PDiag(diag::err_access_dtor_temp) 4878 << Bind->getType()); 4879 DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()); 4880 4881 // We need a cleanup, but we don't need to remember the temporary. 4882 ExprNeedsCleanups = true; 4883 } 4884 4885 // Possibly strip off the top CXXBindTemporaryExpr. 4886 return Owned(E); 4887} 4888 4889ExprResult 4890Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4891 tok::TokenKind OpKind, ParsedType &ObjectType, 4892 bool &MayBePseudoDestructor) { 4893 // Since this might be a postfix expression, get rid of ParenListExprs. 4894 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4895 if (Result.isInvalid()) return ExprError(); 4896 Base = Result.get(); 4897 4898 Result = CheckPlaceholderExpr(Base); 4899 if (Result.isInvalid()) return ExprError(); 4900 Base = Result.take(); 4901 4902 QualType BaseType = Base->getType(); 4903 MayBePseudoDestructor = false; 4904 if (BaseType->isDependentType()) { 4905 // If we have a pointer to a dependent type and are using the -> operator, 4906 // the object type is the type that the pointer points to. We might still 4907 // have enough information about that type to do something useful. 4908 if (OpKind == tok::arrow) 4909 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 4910 BaseType = Ptr->getPointeeType(); 4911 4912 ObjectType = ParsedType::make(BaseType); 4913 MayBePseudoDestructor = true; 4914 return Owned(Base); 4915 } 4916 4917 // C++ [over.match.oper]p8: 4918 // [...] When operator->returns, the operator-> is applied to the value 4919 // returned, with the original second operand. 4920 if (OpKind == tok::arrow) { 4921 // The set of types we've considered so far. 4922 llvm::SmallPtrSet<CanQualType,8> CTypes; 4923 SmallVector<SourceLocation, 8> Locations; 4924 CTypes.insert(Context.getCanonicalType(BaseType)); 4925 4926 while (BaseType->isRecordType()) { 4927 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 4928 if (Result.isInvalid()) 4929 return ExprError(); 4930 Base = Result.get(); 4931 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 4932 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 4933 BaseType = Base->getType(); 4934 CanQualType CBaseType = Context.getCanonicalType(BaseType); 4935 if (!CTypes.insert(CBaseType)) { 4936 Diag(OpLoc, diag::err_operator_arrow_circular); 4937 for (unsigned i = 0; i < Locations.size(); i++) 4938 Diag(Locations[i], diag::note_declared_at); 4939 return ExprError(); 4940 } 4941 } 4942 4943 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 4944 BaseType = BaseType->getPointeeType(); 4945 } 4946 4947 // Objective-C properties allow "." access on Objective-C pointer types, 4948 // so adjust the base type to the object type itself. 4949 if (BaseType->isObjCObjectPointerType()) 4950 BaseType = BaseType->getPointeeType(); 4951 4952 // C++ [basic.lookup.classref]p2: 4953 // [...] If the type of the object expression is of pointer to scalar 4954 // type, the unqualified-id is looked up in the context of the complete 4955 // postfix-expression. 4956 // 4957 // This also indicates that we could be parsing a pseudo-destructor-name. 4958 // Note that Objective-C class and object types can be pseudo-destructor 4959 // expressions or normal member (ivar or property) access expressions. 4960 if (BaseType->isObjCObjectOrInterfaceType()) { 4961 MayBePseudoDestructor = true; 4962 } else if (!BaseType->isRecordType()) { 4963 ObjectType = ParsedType(); 4964 MayBePseudoDestructor = true; 4965 return Owned(Base); 4966 } 4967 4968 // The object type must be complete (or dependent), or 4969 // C++11 [expr.prim.general]p3: 4970 // Unlike the object expression in other contexts, *this is not required to 4971 // be of complete type for purposes of class member access (5.2.5) outside 4972 // the member function body. 4973 if (!BaseType->isDependentType() && 4974 !isThisOutsideMemberFunctionBody(BaseType) && 4975 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access)) 4976 return ExprError(); 4977 4978 // C++ [basic.lookup.classref]p2: 4979 // If the id-expression in a class member access (5.2.5) is an 4980 // unqualified-id, and the type of the object expression is of a class 4981 // type C (or of pointer to a class type C), the unqualified-id is looked 4982 // up in the scope of class C. [...] 4983 ObjectType = ParsedType::make(BaseType); 4984 return Base; 4985} 4986 4987ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 4988 Expr *MemExpr) { 4989 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 4990 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 4991 << isa<CXXPseudoDestructorExpr>(MemExpr) 4992 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 4993 4994 return ActOnCallExpr(/*Scope*/ 0, 4995 MemExpr, 4996 /*LPLoc*/ ExpectedLParenLoc, 4997 MultiExprArg(), 4998 /*RPLoc*/ ExpectedLParenLoc); 4999} 5000 5001static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 5002 tok::TokenKind& OpKind, SourceLocation OpLoc) { 5003 if (Base->hasPlaceholderType()) { 5004 ExprResult result = S.CheckPlaceholderExpr(Base); 5005 if (result.isInvalid()) return true; 5006 Base = result.take(); 5007 } 5008 ObjectType = Base->getType(); 5009 5010 // C++ [expr.pseudo]p2: 5011 // The left-hand side of the dot operator shall be of scalar type. The 5012 // left-hand side of the arrow operator shall be of pointer to scalar type. 5013 // This scalar type is the object type. 5014 // Note that this is rather different from the normal handling for the 5015 // arrow operator. 5016 if (OpKind == tok::arrow) { 5017 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 5018 ObjectType = Ptr->getPointeeType(); 5019 } else if (!Base->isTypeDependent()) { 5020 // The user wrote "p->" when she probably meant "p."; fix it. 5021 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 5022 << ObjectType << true 5023 << FixItHint::CreateReplacement(OpLoc, "."); 5024 if (S.isSFINAEContext()) 5025 return true; 5026 5027 OpKind = tok::period; 5028 } 5029 } 5030 5031 return false; 5032} 5033 5034ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 5035 SourceLocation OpLoc, 5036 tok::TokenKind OpKind, 5037 const CXXScopeSpec &SS, 5038 TypeSourceInfo *ScopeTypeInfo, 5039 SourceLocation CCLoc, 5040 SourceLocation TildeLoc, 5041 PseudoDestructorTypeStorage Destructed, 5042 bool HasTrailingLParen) { 5043 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 5044 5045 QualType ObjectType; 5046 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5047 return ExprError(); 5048 5049 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() && 5050 !ObjectType->isVectorType()) { 5051 if (getLangOpts().MicrosoftMode && ObjectType->isVoidType()) 5052 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 5053 else 5054 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 5055 << ObjectType << Base->getSourceRange(); 5056 return ExprError(); 5057 } 5058 5059 // C++ [expr.pseudo]p2: 5060 // [...] The cv-unqualified versions of the object type and of the type 5061 // designated by the pseudo-destructor-name shall be the same type. 5062 if (DestructedTypeInfo) { 5063 QualType DestructedType = DestructedTypeInfo->getType(); 5064 SourceLocation DestructedTypeStart 5065 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 5066 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 5067 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 5068 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 5069 << ObjectType << DestructedType << Base->getSourceRange() 5070 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5071 5072 // Recover by setting the destructed type to the object type. 5073 DestructedType = ObjectType; 5074 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5075 DestructedTypeStart); 5076 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5077 } else if (DestructedType.getObjCLifetime() != 5078 ObjectType.getObjCLifetime()) { 5079 5080 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 5081 // Okay: just pretend that the user provided the correctly-qualified 5082 // type. 5083 } else { 5084 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 5085 << ObjectType << DestructedType << Base->getSourceRange() 5086 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 5087 } 5088 5089 // Recover by setting the destructed type to the object type. 5090 DestructedType = ObjectType; 5091 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 5092 DestructedTypeStart); 5093 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5094 } 5095 } 5096 } 5097 5098 // C++ [expr.pseudo]p2: 5099 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 5100 // form 5101 // 5102 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 5103 // 5104 // shall designate the same scalar type. 5105 if (ScopeTypeInfo) { 5106 QualType ScopeType = ScopeTypeInfo->getType(); 5107 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 5108 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 5109 5110 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 5111 diag::err_pseudo_dtor_type_mismatch) 5112 << ObjectType << ScopeType << Base->getSourceRange() 5113 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 5114 5115 ScopeType = QualType(); 5116 ScopeTypeInfo = 0; 5117 } 5118 } 5119 5120 Expr *Result 5121 = new (Context) CXXPseudoDestructorExpr(Context, Base, 5122 OpKind == tok::arrow, OpLoc, 5123 SS.getWithLocInContext(Context), 5124 ScopeTypeInfo, 5125 CCLoc, 5126 TildeLoc, 5127 Destructed); 5128 5129 if (HasTrailingLParen) 5130 return Owned(Result); 5131 5132 return DiagnoseDtorReference(Destructed.getLocation(), Result); 5133} 5134 5135ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5136 SourceLocation OpLoc, 5137 tok::TokenKind OpKind, 5138 CXXScopeSpec &SS, 5139 UnqualifiedId &FirstTypeName, 5140 SourceLocation CCLoc, 5141 SourceLocation TildeLoc, 5142 UnqualifiedId &SecondTypeName, 5143 bool HasTrailingLParen) { 5144 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5145 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5146 "Invalid first type name in pseudo-destructor"); 5147 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5148 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 5149 "Invalid second type name in pseudo-destructor"); 5150 5151 QualType ObjectType; 5152 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5153 return ExprError(); 5154 5155 // Compute the object type that we should use for name lookup purposes. Only 5156 // record types and dependent types matter. 5157 ParsedType ObjectTypePtrForLookup; 5158 if (!SS.isSet()) { 5159 if (ObjectType->isRecordType()) 5160 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 5161 else if (ObjectType->isDependentType()) 5162 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 5163 } 5164 5165 // Convert the name of the type being destructed (following the ~) into a 5166 // type (with source-location information). 5167 QualType DestructedType; 5168 TypeSourceInfo *DestructedTypeInfo = 0; 5169 PseudoDestructorTypeStorage Destructed; 5170 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5171 ParsedType T = getTypeName(*SecondTypeName.Identifier, 5172 SecondTypeName.StartLocation, 5173 S, &SS, true, false, ObjectTypePtrForLookup); 5174 if (!T && 5175 ((SS.isSet() && !computeDeclContext(SS, false)) || 5176 (!SS.isSet() && ObjectType->isDependentType()))) { 5177 // The name of the type being destroyed is a dependent name, and we 5178 // couldn't find anything useful in scope. Just store the identifier and 5179 // it's location, and we'll perform (qualified) name lookup again at 5180 // template instantiation time. 5181 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 5182 SecondTypeName.StartLocation); 5183 } else if (!T) { 5184 Diag(SecondTypeName.StartLocation, 5185 diag::err_pseudo_dtor_destructor_non_type) 5186 << SecondTypeName.Identifier << ObjectType; 5187 if (isSFINAEContext()) 5188 return ExprError(); 5189 5190 // Recover by assuming we had the right type all along. 5191 DestructedType = ObjectType; 5192 } else 5193 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 5194 } else { 5195 // Resolve the template-id to a type. 5196 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 5197 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5198 TemplateId->NumArgs); 5199 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5200 TemplateId->TemplateKWLoc, 5201 TemplateId->Template, 5202 TemplateId->TemplateNameLoc, 5203 TemplateId->LAngleLoc, 5204 TemplateArgsPtr, 5205 TemplateId->RAngleLoc); 5206 if (T.isInvalid() || !T.get()) { 5207 // Recover by assuming we had the right type all along. 5208 DestructedType = ObjectType; 5209 } else 5210 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 5211 } 5212 5213 // If we've performed some kind of recovery, (re-)build the type source 5214 // information. 5215 if (!DestructedType.isNull()) { 5216 if (!DestructedTypeInfo) 5217 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 5218 SecondTypeName.StartLocation); 5219 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5220 } 5221 5222 // Convert the name of the scope type (the type prior to '::') into a type. 5223 TypeSourceInfo *ScopeTypeInfo = 0; 5224 QualType ScopeType; 5225 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5226 FirstTypeName.Identifier) { 5227 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5228 ParsedType T = getTypeName(*FirstTypeName.Identifier, 5229 FirstTypeName.StartLocation, 5230 S, &SS, true, false, ObjectTypePtrForLookup); 5231 if (!T) { 5232 Diag(FirstTypeName.StartLocation, 5233 diag::err_pseudo_dtor_destructor_non_type) 5234 << FirstTypeName.Identifier << ObjectType; 5235 5236 if (isSFINAEContext()) 5237 return ExprError(); 5238 5239 // Just drop this type. It's unnecessary anyway. 5240 ScopeType = QualType(); 5241 } else 5242 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 5243 } else { 5244 // Resolve the template-id to a type. 5245 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 5246 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 5247 TemplateId->NumArgs); 5248 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5249 TemplateId->TemplateKWLoc, 5250 TemplateId->Template, 5251 TemplateId->TemplateNameLoc, 5252 TemplateId->LAngleLoc, 5253 TemplateArgsPtr, 5254 TemplateId->RAngleLoc); 5255 if (T.isInvalid() || !T.get()) { 5256 // Recover by dropping this type. 5257 ScopeType = QualType(); 5258 } else 5259 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 5260 } 5261 } 5262 5263 if (!ScopeType.isNull() && !ScopeTypeInfo) 5264 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 5265 FirstTypeName.StartLocation); 5266 5267 5268 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 5269 ScopeTypeInfo, CCLoc, TildeLoc, 5270 Destructed, HasTrailingLParen); 5271} 5272 5273ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5274 SourceLocation OpLoc, 5275 tok::TokenKind OpKind, 5276 SourceLocation TildeLoc, 5277 const DeclSpec& DS, 5278 bool HasTrailingLParen) { 5279 QualType ObjectType; 5280 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5281 return ExprError(); 5282 5283 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 5284 5285 TypeLocBuilder TLB; 5286 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 5287 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 5288 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 5289 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 5290 5291 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 5292 0, SourceLocation(), TildeLoc, 5293 Destructed, HasTrailingLParen); 5294} 5295 5296ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 5297 CXXConversionDecl *Method, 5298 bool HadMultipleCandidates) { 5299 if (Method->getParent()->isLambda() && 5300 Method->getConversionType()->isBlockPointerType()) { 5301 // This is a lambda coversion to block pointer; check if the argument 5302 // is a LambdaExpr. 5303 Expr *SubE = E; 5304 CastExpr *CE = dyn_cast<CastExpr>(SubE); 5305 if (CE && CE->getCastKind() == CK_NoOp) 5306 SubE = CE->getSubExpr(); 5307 SubE = SubE->IgnoreParens(); 5308 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE)) 5309 SubE = BE->getSubExpr(); 5310 if (isa<LambdaExpr>(SubE)) { 5311 // For the conversion to block pointer on a lambda expression, we 5312 // construct a special BlockLiteral instead; this doesn't really make 5313 // a difference in ARC, but outside of ARC the resulting block literal 5314 // follows the normal lifetime rules for block literals instead of being 5315 // autoreleased. 5316 DiagnosticErrorTrap Trap(Diags); 5317 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(), 5318 E->getExprLoc(), 5319 Method, E); 5320 if (Exp.isInvalid()) 5321 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv); 5322 return Exp; 5323 } 5324 } 5325 5326 5327 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 5328 FoundDecl, Method); 5329 if (Exp.isInvalid()) 5330 return true; 5331 5332 MemberExpr *ME = 5333 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 5334 SourceLocation(), Context.BoundMemberTy, 5335 VK_RValue, OK_Ordinary); 5336 if (HadMultipleCandidates) 5337 ME->setHadMultipleCandidates(true); 5338 5339 QualType ResultType = Method->getResultType(); 5340 ExprValueKind VK = Expr::getValueKindForType(ResultType); 5341 ResultType = ResultType.getNonLValueExprType(Context); 5342 5343 MarkFunctionReferenced(Exp.get()->getLocStart(), Method); 5344 CXXMemberCallExpr *CE = 5345 new (Context) CXXMemberCallExpr(Context, ME, MultiExprArg(), ResultType, VK, 5346 Exp.get()->getLocEnd()); 5347 return CE; 5348} 5349 5350ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 5351 SourceLocation RParen) { 5352 CanThrowResult CanThrow = canThrow(Operand); 5353 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 5354 CanThrow, KeyLoc, RParen)); 5355} 5356 5357ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 5358 Expr *Operand, SourceLocation RParen) { 5359 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 5360} 5361 5362static bool IsSpecialDiscardedValue(Expr *E) { 5363 // In C++11, discarded-value expressions of a certain form are special, 5364 // according to [expr]p10: 5365 // The lvalue-to-rvalue conversion (4.1) is applied only if the 5366 // expression is an lvalue of volatile-qualified type and it has 5367 // one of the following forms: 5368 E = E->IgnoreParens(); 5369 5370 // - id-expression (5.1.1), 5371 if (isa<DeclRefExpr>(E)) 5372 return true; 5373 5374 // - subscripting (5.2.1), 5375 if (isa<ArraySubscriptExpr>(E)) 5376 return true; 5377 5378 // - class member access (5.2.5), 5379 if (isa<MemberExpr>(E)) 5380 return true; 5381 5382 // - indirection (5.3.1), 5383 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) 5384 if (UO->getOpcode() == UO_Deref) 5385 return true; 5386 5387 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 5388 // - pointer-to-member operation (5.5), 5389 if (BO->isPtrMemOp()) 5390 return true; 5391 5392 // - comma expression (5.18) where the right operand is one of the above. 5393 if (BO->getOpcode() == BO_Comma) 5394 return IsSpecialDiscardedValue(BO->getRHS()); 5395 } 5396 5397 // - conditional expression (5.16) where both the second and the third 5398 // operands are one of the above, or 5399 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) 5400 return IsSpecialDiscardedValue(CO->getTrueExpr()) && 5401 IsSpecialDiscardedValue(CO->getFalseExpr()); 5402 // The related edge case of "*x ?: *x". 5403 if (BinaryConditionalOperator *BCO = 5404 dyn_cast<BinaryConditionalOperator>(E)) { 5405 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr())) 5406 return IsSpecialDiscardedValue(OVE->getSourceExpr()) && 5407 IsSpecialDiscardedValue(BCO->getFalseExpr()); 5408 } 5409 5410 // Objective-C++ extensions to the rule. 5411 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E)) 5412 return true; 5413 5414 return false; 5415} 5416 5417/// Perform the conversions required for an expression used in a 5418/// context that ignores the result. 5419ExprResult Sema::IgnoredValueConversions(Expr *E) { 5420 if (E->hasPlaceholderType()) { 5421 ExprResult result = CheckPlaceholderExpr(E); 5422 if (result.isInvalid()) return Owned(E); 5423 E = result.take(); 5424 } 5425 5426 // C99 6.3.2.1: 5427 // [Except in specific positions,] an lvalue that does not have 5428 // array type is converted to the value stored in the 5429 // designated object (and is no longer an lvalue). 5430 if (E->isRValue()) { 5431 // In C, function designators (i.e. expressions of function type) 5432 // are r-values, but we still want to do function-to-pointer decay 5433 // on them. This is both technically correct and convenient for 5434 // some clients. 5435 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType()) 5436 return DefaultFunctionArrayConversion(E); 5437 5438 return Owned(E); 5439 } 5440 5441 if (getLangOpts().CPlusPlus) { 5442 // The C++11 standard defines the notion of a discarded-value expression; 5443 // normally, we don't need to do anything to handle it, but if it is a 5444 // volatile lvalue with a special form, we perform an lvalue-to-rvalue 5445 // conversion. 5446 if (getLangOpts().CPlusPlus11 && E->isGLValue() && 5447 E->getType().isVolatileQualified() && 5448 IsSpecialDiscardedValue(E)) { 5449 ExprResult Res = DefaultLvalueConversion(E); 5450 if (Res.isInvalid()) 5451 return Owned(E); 5452 E = Res.take(); 5453 } 5454 return Owned(E); 5455 } 5456 5457 // GCC seems to also exclude expressions of incomplete enum type. 5458 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 5459 if (!T->getDecl()->isComplete()) { 5460 // FIXME: stupid workaround for a codegen bug! 5461 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 5462 return Owned(E); 5463 } 5464 } 5465 5466 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 5467 if (Res.isInvalid()) 5468 return Owned(E); 5469 E = Res.take(); 5470 5471 if (!E->getType()->isVoidType()) 5472 RequireCompleteType(E->getExprLoc(), E->getType(), 5473 diag::err_incomplete_type); 5474 return Owned(E); 5475} 5476 5477ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC, 5478 bool DiscardedValue, 5479 bool IsConstexpr) { 5480 ExprResult FullExpr = Owned(FE); 5481 5482 if (!FullExpr.get()) 5483 return ExprError(); 5484 5485 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 5486 return ExprError(); 5487 5488 // Top-level message sends default to 'id' when we're in a debugger. 5489 if (DiscardedValue && getLangOpts().DebuggerCastResultToId && 5490 FullExpr.get()->getType() == Context.UnknownAnyTy && 5491 isa<ObjCMessageExpr>(FullExpr.get())) { 5492 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 5493 if (FullExpr.isInvalid()) 5494 return ExprError(); 5495 } 5496 5497 if (DiscardedValue) { 5498 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 5499 if (FullExpr.isInvalid()) 5500 return ExprError(); 5501 5502 FullExpr = IgnoredValueConversions(FullExpr.take()); 5503 if (FullExpr.isInvalid()) 5504 return ExprError(); 5505 } 5506 5507 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr); 5508 return MaybeCreateExprWithCleanups(FullExpr); 5509} 5510 5511StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 5512 if (!FullStmt) return StmtError(); 5513 5514 return MaybeCreateStmtWithCleanups(FullStmt); 5515} 5516 5517Sema::IfExistsResult 5518Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 5519 CXXScopeSpec &SS, 5520 const DeclarationNameInfo &TargetNameInfo) { 5521 DeclarationName TargetName = TargetNameInfo.getName(); 5522 if (!TargetName) 5523 return IER_DoesNotExist; 5524 5525 // If the name itself is dependent, then the result is dependent. 5526 if (TargetName.isDependentName()) 5527 return IER_Dependent; 5528 5529 // Do the redeclaration lookup in the current scope. 5530 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 5531 Sema::NotForRedeclaration); 5532 LookupParsedName(R, S, &SS); 5533 R.suppressDiagnostics(); 5534 5535 switch (R.getResultKind()) { 5536 case LookupResult::Found: 5537 case LookupResult::FoundOverloaded: 5538 case LookupResult::FoundUnresolvedValue: 5539 case LookupResult::Ambiguous: 5540 return IER_Exists; 5541 5542 case LookupResult::NotFound: 5543 return IER_DoesNotExist; 5544 5545 case LookupResult::NotFoundInCurrentInstantiation: 5546 return IER_Dependent; 5547 } 5548 5549 llvm_unreachable("Invalid LookupResult Kind!"); 5550} 5551 5552Sema::IfExistsResult 5553Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 5554 bool IsIfExists, CXXScopeSpec &SS, 5555 UnqualifiedId &Name) { 5556 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 5557 5558 // Check for unexpanded parameter packs. 5559 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 5560 collectUnexpandedParameterPacks(SS, Unexpanded); 5561 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 5562 if (!Unexpanded.empty()) { 5563 DiagnoseUnexpandedParameterPacks(KeywordLoc, 5564 IsIfExists? UPPC_IfExists 5565 : UPPC_IfNotExists, 5566 Unexpanded); 5567 return IER_Error; 5568 } 5569 5570 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 5571} 5572