SemaExprCXX.cpp revision c60ccf5b4fb657ca40da3019c2bbe15dd8ab9732
1//===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for C++ expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/DeclSpec.h" 16#include "clang/Sema/Initialization.h" 17#include "clang/Sema/Lookup.h" 18#include "clang/Sema/ParsedTemplate.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "clang/Sema/Scope.h" 21#include "clang/Sema/TemplateDeduction.h" 22#include "clang/AST/ASTContext.h" 23#include "clang/AST/CharUnits.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/ExprCXX.h" 27#include "clang/AST/ExprObjC.h" 28#include "clang/AST/TypeLoc.h" 29#include "clang/Basic/PartialDiagnostic.h" 30#include "clang/Basic/TargetInfo.h" 31#include "clang/Lex/Preprocessor.h" 32#include "TypeLocBuilder.h" 33#include "llvm/ADT/APInt.h" 34#include "llvm/ADT/STLExtras.h" 35#include "llvm/Support/ErrorHandling.h" 36using namespace clang; 37using namespace sema; 38 39ParsedType Sema::getDestructorName(SourceLocation TildeLoc, 40 IdentifierInfo &II, 41 SourceLocation NameLoc, 42 Scope *S, CXXScopeSpec &SS, 43 ParsedType ObjectTypePtr, 44 bool EnteringContext) { 45 // Determine where to perform name lookup. 46 47 // FIXME: This area of the standard is very messy, and the current 48 // wording is rather unclear about which scopes we search for the 49 // destructor name; see core issues 399 and 555. Issue 399 in 50 // particular shows where the current description of destructor name 51 // lookup is completely out of line with existing practice, e.g., 52 // this appears to be ill-formed: 53 // 54 // namespace N { 55 // template <typename T> struct S { 56 // ~S(); 57 // }; 58 // } 59 // 60 // void f(N::S<int>* s) { 61 // s->N::S<int>::~S(); 62 // } 63 // 64 // See also PR6358 and PR6359. 65 // For this reason, we're currently only doing the C++03 version of this 66 // code; the C++0x version has to wait until we get a proper spec. 67 QualType SearchType; 68 DeclContext *LookupCtx = 0; 69 bool isDependent = false; 70 bool LookInScope = false; 71 72 // If we have an object type, it's because we are in a 73 // pseudo-destructor-expression or a member access expression, and 74 // we know what type we're looking for. 75 if (ObjectTypePtr) 76 SearchType = GetTypeFromParser(ObjectTypePtr); 77 78 if (SS.isSet()) { 79 NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 80 81 bool AlreadySearched = false; 82 bool LookAtPrefix = true; 83 // C++ [basic.lookup.qual]p6: 84 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier, 85 // the type-names are looked up as types in the scope designated by the 86 // nested-name-specifier. In a qualified-id of the form: 87 // 88 // ::[opt] nested-name-specifier ~ class-name 89 // 90 // where the nested-name-specifier designates a namespace scope, and in 91 // a qualified-id of the form: 92 // 93 // ::opt nested-name-specifier class-name :: ~ class-name 94 // 95 // the class-names are looked up as types in the scope designated by 96 // the nested-name-specifier. 97 // 98 // Here, we check the first case (completely) and determine whether the 99 // code below is permitted to look at the prefix of the 100 // nested-name-specifier. 101 DeclContext *DC = computeDeclContext(SS, EnteringContext); 102 if (DC && DC->isFileContext()) { 103 AlreadySearched = true; 104 LookupCtx = DC; 105 isDependent = false; 106 } else if (DC && isa<CXXRecordDecl>(DC)) 107 LookAtPrefix = false; 108 109 // The second case from the C++03 rules quoted further above. 110 NestedNameSpecifier *Prefix = 0; 111 if (AlreadySearched) { 112 // Nothing left to do. 113 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) { 114 CXXScopeSpec PrefixSS; 115 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data())); 116 LookupCtx = computeDeclContext(PrefixSS, EnteringContext); 117 isDependent = isDependentScopeSpecifier(PrefixSS); 118 } else if (ObjectTypePtr) { 119 LookupCtx = computeDeclContext(SearchType); 120 isDependent = SearchType->isDependentType(); 121 } else { 122 LookupCtx = computeDeclContext(SS, EnteringContext); 123 isDependent = LookupCtx && LookupCtx->isDependentContext(); 124 } 125 126 LookInScope = false; 127 } else if (ObjectTypePtr) { 128 // C++ [basic.lookup.classref]p3: 129 // If the unqualified-id is ~type-name, the type-name is looked up 130 // in the context of the entire postfix-expression. If the type T 131 // of the object expression is of a class type C, the type-name is 132 // also looked up in the scope of class C. At least one of the 133 // lookups shall find a name that refers to (possibly 134 // cv-qualified) T. 135 LookupCtx = computeDeclContext(SearchType); 136 isDependent = SearchType->isDependentType(); 137 assert((isDependent || !SearchType->isIncompleteType()) && 138 "Caller should have completed object type"); 139 140 LookInScope = true; 141 } else { 142 // Perform lookup into the current scope (only). 143 LookInScope = true; 144 } 145 146 TypeDecl *NonMatchingTypeDecl = 0; 147 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName); 148 for (unsigned Step = 0; Step != 2; ++Step) { 149 // Look for the name first in the computed lookup context (if we 150 // have one) and, if that fails to find a match, in the scope (if 151 // we're allowed to look there). 152 Found.clear(); 153 if (Step == 0 && LookupCtx) 154 LookupQualifiedName(Found, LookupCtx); 155 else if (Step == 1 && LookInScope && S) 156 LookupName(Found, S); 157 else 158 continue; 159 160 // FIXME: Should we be suppressing ambiguities here? 161 if (Found.isAmbiguous()) 162 return ParsedType(); 163 164 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) { 165 QualType T = Context.getTypeDeclType(Type); 166 167 if (SearchType.isNull() || SearchType->isDependentType() || 168 Context.hasSameUnqualifiedType(T, SearchType)) { 169 // We found our type! 170 171 return ParsedType::make(T); 172 } 173 174 if (!SearchType.isNull()) 175 NonMatchingTypeDecl = Type; 176 } 177 178 // If the name that we found is a class template name, and it is 179 // the same name as the template name in the last part of the 180 // nested-name-specifier (if present) or the object type, then 181 // this is the destructor for that class. 182 // FIXME: This is a workaround until we get real drafting for core 183 // issue 399, for which there isn't even an obvious direction. 184 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) { 185 QualType MemberOfType; 186 if (SS.isSet()) { 187 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) { 188 // Figure out the type of the context, if it has one. 189 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) 190 MemberOfType = Context.getTypeDeclType(Record); 191 } 192 } 193 if (MemberOfType.isNull()) 194 MemberOfType = SearchType; 195 196 if (MemberOfType.isNull()) 197 continue; 198 199 // We're referring into a class template specialization. If the 200 // class template we found is the same as the template being 201 // specialized, we found what we are looking for. 202 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) { 203 if (ClassTemplateSpecializationDecl *Spec 204 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) { 205 if (Spec->getSpecializedTemplate()->getCanonicalDecl() == 206 Template->getCanonicalDecl()) 207 return ParsedType::make(MemberOfType); 208 } 209 210 continue; 211 } 212 213 // We're referring to an unresolved class template 214 // specialization. Determine whether we class template we found 215 // is the same as the template being specialized or, if we don't 216 // know which template is being specialized, that it at least 217 // has the same name. 218 if (const TemplateSpecializationType *SpecType 219 = MemberOfType->getAs<TemplateSpecializationType>()) { 220 TemplateName SpecName = SpecType->getTemplateName(); 221 222 // The class template we found is the same template being 223 // specialized. 224 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) { 225 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl()) 226 return ParsedType::make(MemberOfType); 227 228 continue; 229 } 230 231 // The class template we found has the same name as the 232 // (dependent) template name being specialized. 233 if (DependentTemplateName *DepTemplate 234 = SpecName.getAsDependentTemplateName()) { 235 if (DepTemplate->isIdentifier() && 236 DepTemplate->getIdentifier() == Template->getIdentifier()) 237 return ParsedType::make(MemberOfType); 238 239 continue; 240 } 241 } 242 } 243 } 244 245 if (isDependent) { 246 // We didn't find our type, but that's okay: it's dependent 247 // anyway. 248 249 // FIXME: What if we have no nested-name-specifier? 250 QualType T = CheckTypenameType(ETK_None, SourceLocation(), 251 SS.getWithLocInContext(Context), 252 II, NameLoc); 253 return ParsedType::make(T); 254 } 255 256 if (NonMatchingTypeDecl) { 257 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl); 258 Diag(NameLoc, diag::err_destructor_expr_type_mismatch) 259 << T << SearchType; 260 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here) 261 << T; 262 } else if (ObjectTypePtr) 263 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type) 264 << &II; 265 else 266 Diag(NameLoc, diag::err_destructor_class_name); 267 268 return ParsedType(); 269} 270 271ParsedType Sema::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) { 272 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType) 273 return ParsedType(); 274 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype 275 && "only get destructor types from declspecs"); 276 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 277 QualType SearchType = GetTypeFromParser(ObjectType); 278 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) { 279 return ParsedType::make(T); 280 } 281 282 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch) 283 << T << SearchType; 284 return ParsedType(); 285} 286 287/// \brief Build a C++ typeid expression with a type operand. 288ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 289 SourceLocation TypeidLoc, 290 TypeSourceInfo *Operand, 291 SourceLocation RParenLoc) { 292 // C++ [expr.typeid]p4: 293 // The top-level cv-qualifiers of the lvalue expression or the type-id 294 // that is the operand of typeid are always ignored. 295 // If the type of the type-id is a class type or a reference to a class 296 // type, the class shall be completely-defined. 297 Qualifiers Quals; 298 QualType T 299 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(), 300 Quals); 301 if (T->getAs<RecordType>() && 302 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 303 return ExprError(); 304 305 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 306 Operand, 307 SourceRange(TypeidLoc, RParenLoc))); 308} 309 310/// \brief Build a C++ typeid expression with an expression operand. 311ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType, 312 SourceLocation TypeidLoc, 313 Expr *E, 314 SourceLocation RParenLoc) { 315 if (E && !E->isTypeDependent()) { 316 if (E->getType()->isPlaceholderType()) { 317 ExprResult result = CheckPlaceholderExpr(E); 318 if (result.isInvalid()) return ExprError(); 319 E = result.take(); 320 } 321 322 QualType T = E->getType(); 323 if (const RecordType *RecordT = T->getAs<RecordType>()) { 324 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl()); 325 // C++ [expr.typeid]p3: 326 // [...] If the type of the expression is a class type, the class 327 // shall be completely-defined. 328 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid)) 329 return ExprError(); 330 331 // C++ [expr.typeid]p3: 332 // When typeid is applied to an expression other than an glvalue of a 333 // polymorphic class type [...] [the] expression is an unevaluated 334 // operand. [...] 335 if (RecordD->isPolymorphic() && E->Classify(Context).isGLValue()) { 336 // The subexpression is potentially evaluated; switch the context 337 // and recheck the subexpression. 338 ExprResult Result = TranformToPotentiallyEvaluated(E); 339 if (Result.isInvalid()) return ExprError(); 340 E = Result.take(); 341 342 // We require a vtable to query the type at run time. 343 MarkVTableUsed(TypeidLoc, RecordD); 344 } 345 } 346 347 // C++ [expr.typeid]p4: 348 // [...] If the type of the type-id is a reference to a possibly 349 // cv-qualified type, the result of the typeid expression refers to a 350 // std::type_info object representing the cv-unqualified referenced 351 // type. 352 Qualifiers Quals; 353 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals); 354 if (!Context.hasSameType(T, UnqualT)) { 355 T = UnqualT; 356 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).take(); 357 } 358 } 359 360 return Owned(new (Context) CXXTypeidExpr(TypeInfoType.withConst(), 361 E, 362 SourceRange(TypeidLoc, RParenLoc))); 363} 364 365/// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression); 366ExprResult 367Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc, 368 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 369 // Find the std::type_info type. 370 if (!getStdNamespace()) 371 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 372 373 if (!CXXTypeInfoDecl) { 374 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info"); 375 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName); 376 LookupQualifiedName(R, getStdNamespace()); 377 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>(); 378 if (!CXXTypeInfoDecl) 379 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid)); 380 } 381 382 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl); 383 384 if (isType) { 385 // The operand is a type; handle it as such. 386 TypeSourceInfo *TInfo = 0; 387 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 388 &TInfo); 389 if (T.isNull()) 390 return ExprError(); 391 392 if (!TInfo) 393 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 394 395 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc); 396 } 397 398 // The operand is an expression. 399 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 400} 401 402/// Retrieve the UuidAttr associated with QT. 403static UuidAttr *GetUuidAttrOfType(QualType QT) { 404 // Optionally remove one level of pointer, reference or array indirection. 405 const Type *Ty = QT.getTypePtr();; 406 if (QT->isPointerType() || QT->isReferenceType()) 407 Ty = QT->getPointeeType().getTypePtr(); 408 else if (QT->isArrayType()) 409 Ty = cast<ArrayType>(QT)->getElementType().getTypePtr(); 410 411 // Loop all record redeclaration looking for an uuid attribute. 412 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl(); 413 for (CXXRecordDecl::redecl_iterator I = RD->redecls_begin(), 414 E = RD->redecls_end(); I != E; ++I) { 415 if (UuidAttr *Uuid = I->getAttr<UuidAttr>()) 416 return Uuid; 417 } 418 419 return 0; 420} 421 422/// \brief Build a Microsoft __uuidof expression with a type operand. 423ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 424 SourceLocation TypeidLoc, 425 TypeSourceInfo *Operand, 426 SourceLocation RParenLoc) { 427 if (!Operand->getType()->isDependentType()) { 428 if (!GetUuidAttrOfType(Operand->getType())) 429 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 430 } 431 432 // FIXME: add __uuidof semantic analysis for type operand. 433 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 434 Operand, 435 SourceRange(TypeidLoc, RParenLoc))); 436} 437 438/// \brief Build a Microsoft __uuidof expression with an expression operand. 439ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType, 440 SourceLocation TypeidLoc, 441 Expr *E, 442 SourceLocation RParenLoc) { 443 if (!E->getType()->isDependentType()) { 444 if (!GetUuidAttrOfType(E->getType()) && 445 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 446 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid)); 447 } 448 // FIXME: add __uuidof semantic analysis for type operand. 449 return Owned(new (Context) CXXUuidofExpr(TypeInfoType.withConst(), 450 E, 451 SourceRange(TypeidLoc, RParenLoc))); 452} 453 454/// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression); 455ExprResult 456Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc, 457 bool isType, void *TyOrExpr, SourceLocation RParenLoc) { 458 // If MSVCGuidDecl has not been cached, do the lookup. 459 if (!MSVCGuidDecl) { 460 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID"); 461 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName); 462 LookupQualifiedName(R, Context.getTranslationUnitDecl()); 463 MSVCGuidDecl = R.getAsSingle<RecordDecl>(); 464 if (!MSVCGuidDecl) 465 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof)); 466 } 467 468 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl); 469 470 if (isType) { 471 // The operand is a type; handle it as such. 472 TypeSourceInfo *TInfo = 0; 473 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr), 474 &TInfo); 475 if (T.isNull()) 476 return ExprError(); 477 478 if (!TInfo) 479 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc); 480 481 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc); 482 } 483 484 // The operand is an expression. 485 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc); 486} 487 488/// ActOnCXXBoolLiteral - Parse {true,false} literals. 489ExprResult 490Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 491 assert((Kind == tok::kw_true || Kind == tok::kw_false) && 492 "Unknown C++ Boolean value!"); 493 return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true, 494 Context.BoolTy, OpLoc)); 495} 496 497/// ActOnCXXNullPtrLiteral - Parse 'nullptr'. 498ExprResult 499Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) { 500 return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc)); 501} 502 503/// ActOnCXXThrow - Parse throw expressions. 504ExprResult 505Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) { 506 bool IsThrownVarInScope = false; 507 if (Ex) { 508 // C++0x [class.copymove]p31: 509 // When certain criteria are met, an implementation is allowed to omit the 510 // copy/move construction of a class object [...] 511 // 512 // - in a throw-expression, when the operand is the name of a 513 // non-volatile automatic object (other than a function or catch- 514 // clause parameter) whose scope does not extend beyond the end of the 515 // innermost enclosing try-block (if there is one), the copy/move 516 // operation from the operand to the exception object (15.1) can be 517 // omitted by constructing the automatic object directly into the 518 // exception object 519 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens())) 520 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 521 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) { 522 for( ; S; S = S->getParent()) { 523 if (S->isDeclScope(Var)) { 524 IsThrownVarInScope = true; 525 break; 526 } 527 528 if (S->getFlags() & 529 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope | 530 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope | 531 Scope::TryScope)) 532 break; 533 } 534 } 535 } 536 } 537 538 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope); 539} 540 541ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex, 542 bool IsThrownVarInScope) { 543 // Don't report an error if 'throw' is used in system headers. 544 if (!getLangOptions().CXXExceptions && 545 !getSourceManager().isInSystemHeader(OpLoc)) 546 Diag(OpLoc, diag::err_exceptions_disabled) << "throw"; 547 548 if (Ex && !Ex->isTypeDependent()) { 549 ExprResult ExRes = CheckCXXThrowOperand(OpLoc, Ex, IsThrownVarInScope); 550 if (ExRes.isInvalid()) 551 return ExprError(); 552 Ex = ExRes.take(); 553 } 554 555 return Owned(new (Context) CXXThrowExpr(Ex, Context.VoidTy, OpLoc, 556 IsThrownVarInScope)); 557} 558 559/// CheckCXXThrowOperand - Validate the operand of a throw. 560ExprResult Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *E, 561 bool IsThrownVarInScope) { 562 // C++ [except.throw]p3: 563 // A throw-expression initializes a temporary object, called the exception 564 // object, the type of which is determined by removing any top-level 565 // cv-qualifiers from the static type of the operand of throw and adjusting 566 // the type from "array of T" or "function returning T" to "pointer to T" 567 // or "pointer to function returning T", [...] 568 if (E->getType().hasQualifiers()) 569 E = ImpCastExprToType(E, E->getType().getUnqualifiedType(), CK_NoOp, 570 E->getValueKind()).take(); 571 572 ExprResult Res = DefaultFunctionArrayConversion(E); 573 if (Res.isInvalid()) 574 return ExprError(); 575 E = Res.take(); 576 577 // If the type of the exception would be an incomplete type or a pointer 578 // to an incomplete type other than (cv) void the program is ill-formed. 579 QualType Ty = E->getType(); 580 bool isPointer = false; 581 if (const PointerType* Ptr = Ty->getAs<PointerType>()) { 582 Ty = Ptr->getPointeeType(); 583 isPointer = true; 584 } 585 if (!isPointer || !Ty->isVoidType()) { 586 if (RequireCompleteType(ThrowLoc, Ty, 587 PDiag(isPointer ? diag::err_throw_incomplete_ptr 588 : diag::err_throw_incomplete) 589 << E->getSourceRange())) 590 return ExprError(); 591 592 if (RequireNonAbstractType(ThrowLoc, E->getType(), 593 PDiag(diag::err_throw_abstract_type) 594 << E->getSourceRange())) 595 return ExprError(); 596 } 597 598 // Initialize the exception result. This implicitly weeds out 599 // abstract types or types with inaccessible copy constructors. 600 601 // C++0x [class.copymove]p31: 602 // When certain criteria are met, an implementation is allowed to omit the 603 // copy/move construction of a class object [...] 604 // 605 // - in a throw-expression, when the operand is the name of a 606 // non-volatile automatic object (other than a function or catch-clause 607 // parameter) whose scope does not extend beyond the end of the 608 // innermost enclosing try-block (if there is one), the copy/move 609 // operation from the operand to the exception object (15.1) can be 610 // omitted by constructing the automatic object directly into the 611 // exception object 612 const VarDecl *NRVOVariable = 0; 613 if (IsThrownVarInScope) 614 NRVOVariable = getCopyElisionCandidate(QualType(), E, false); 615 616 InitializedEntity Entity = 617 InitializedEntity::InitializeException(ThrowLoc, E->getType(), 618 /*NRVO=*/NRVOVariable != 0); 619 Res = PerformMoveOrCopyInitialization(Entity, NRVOVariable, 620 QualType(), E, 621 IsThrownVarInScope); 622 if (Res.isInvalid()) 623 return ExprError(); 624 E = Res.take(); 625 626 // If the exception has class type, we need additional handling. 627 const RecordType *RecordTy = Ty->getAs<RecordType>(); 628 if (!RecordTy) 629 return Owned(E); 630 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl()); 631 632 // If we are throwing a polymorphic class type or pointer thereof, 633 // exception handling will make use of the vtable. 634 MarkVTableUsed(ThrowLoc, RD); 635 636 // If a pointer is thrown, the referenced object will not be destroyed. 637 if (isPointer) 638 return Owned(E); 639 640 // If the class has a destructor, we must be able to call it. 641 if (RD->hasIrrelevantDestructor()) 642 return Owned(E); 643 644 CXXDestructorDecl *Destructor 645 = const_cast<CXXDestructorDecl*>(LookupDestructor(RD)); 646 if (!Destructor) 647 return Owned(E); 648 649 MarkFunctionReferenced(E->getExprLoc(), Destructor); 650 CheckDestructorAccess(E->getExprLoc(), Destructor, 651 PDiag(diag::err_access_dtor_exception) << Ty); 652 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 653 return Owned(E); 654} 655 656QualType Sema::getCurrentThisType() { 657 DeclContext *DC = getFunctionLevelDeclContext(); 658 QualType ThisTy; 659 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) { 660 if (method && method->isInstance()) 661 ThisTy = method->getThisType(Context); 662 } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 663 // C++0x [expr.prim]p4: 664 // Otherwise, if a member-declarator declares a non-static data member 665 // of a class X, the expression this is a prvalue of type "pointer to X" 666 // within the optional brace-or-equal-initializer. 667 Scope *S = getScopeForContext(DC); 668 if (!S || S->getFlags() & Scope::ThisScope) 669 ThisTy = Context.getPointerType(Context.getRecordType(RD)); 670 } 671 672 return ThisTy; 673} 674 675void Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit) { 676 // We don't need to capture this in an unevaluated context. 677 if (ExprEvalContexts.back().Context == Unevaluated && !Explicit) 678 return; 679 680 // Otherwise, check that we can capture 'this'. 681 unsigned NumClosures = 0; 682 for (unsigned idx = FunctionScopes.size() - 1; idx != 0; idx--) { 683 if (CapturingScopeInfo *CSI = 684 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) { 685 if (CSI->CXXThisCaptureIndex != 0) { 686 // 'this' is already being captured; there isn't anything more to do. 687 break; 688 } 689 690 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref || 691 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval || 692 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block || 693 Explicit) { 694 // This closure can capture 'this'; continue looking upwards. 695 NumClosures++; 696 Explicit = false; 697 continue; 698 } 699 // This context can't implicitly capture 'this'; fail out. 700 Diag(Loc, diag::err_this_capture) << Explicit; 701 return; 702 } 703 break; 704 } 705 706 // Mark that we're implicitly capturing 'this' in all the scopes we skipped. 707 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated 708 // contexts. 709 for (unsigned idx = FunctionScopes.size() - 1; 710 NumClosures; --idx, --NumClosures) { 711 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]); 712 Expr *ThisExpr = 0; 713 QualType ThisTy = getCurrentThisType(); 714 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) { 715 // For lambda expressions, build a field and an initializing expression. 716 CXXRecordDecl *Lambda = LSI->Lambda; 717 FieldDecl *Field 718 = FieldDecl::Create(Context, Lambda, Loc, Loc, 0, ThisTy, 719 Context.getTrivialTypeSourceInfo(ThisTy, Loc), 720 0, false, false); 721 Field->setImplicit(true); 722 Field->setAccess(AS_private); 723 Lambda->addDecl(Field); 724 ThisExpr = new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/true); 725 } 726 bool isNested = NumClosures > 1; 727 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr); 728 } 729} 730 731ExprResult Sema::ActOnCXXThis(SourceLocation Loc) { 732 /// C++ 9.3.2: In the body of a non-static member function, the keyword this 733 /// is a non-lvalue expression whose value is the address of the object for 734 /// which the function is called. 735 736 QualType ThisTy = getCurrentThisType(); 737 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use); 738 739 CheckCXXThisCapture(Loc); 740 return Owned(new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false)); 741} 742 743ExprResult 744Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep, 745 SourceLocation LParenLoc, 746 MultiExprArg exprs, 747 SourceLocation RParenLoc) { 748 if (!TypeRep) 749 return ExprError(); 750 751 TypeSourceInfo *TInfo; 752 QualType Ty = GetTypeFromParser(TypeRep, &TInfo); 753 if (!TInfo) 754 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation()); 755 756 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc); 757} 758 759/// ActOnCXXTypeConstructExpr - Parse construction of a specified type. 760/// Can be interpreted either as function-style casting ("int(x)") 761/// or class type construction ("ClassType(x,y,z)") 762/// or creation of a value-initialized type ("int()"). 763ExprResult 764Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, 765 SourceLocation LParenLoc, 766 MultiExprArg exprs, 767 SourceLocation RParenLoc) { 768 QualType Ty = TInfo->getType(); 769 unsigned NumExprs = exprs.size(); 770 Expr **Exprs = (Expr**)exprs.get(); 771 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); 772 773 if (Ty->isDependentType() || 774 CallExpr::hasAnyTypeDependentArguments( 775 llvm::makeArrayRef(Exprs, NumExprs))) { 776 exprs.release(); 777 778 return Owned(CXXUnresolvedConstructExpr::Create(Context, TInfo, 779 LParenLoc, 780 Exprs, NumExprs, 781 RParenLoc)); 782 } 783 784 bool ListInitialization = LParenLoc.isInvalid(); 785 assert((!ListInitialization || (NumExprs == 1 && isa<InitListExpr>(Exprs[0]))) 786 && "List initialization must have initializer list as expression."); 787 SourceRange FullRange = SourceRange(TyBeginLoc, 788 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc); 789 790 // C++ [expr.type.conv]p1: 791 // If the expression list is a single expression, the type conversion 792 // expression is equivalent (in definedness, and if defined in meaning) to the 793 // corresponding cast expression. 794 if (NumExprs == 1 && !ListInitialization) { 795 Expr *Arg = Exprs[0]; 796 exprs.release(); 797 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc); 798 } 799 800 QualType ElemTy = Ty; 801 if (Ty->isArrayType()) { 802 if (!ListInitialization) 803 return ExprError(Diag(TyBeginLoc, 804 diag::err_value_init_for_array_type) << FullRange); 805 ElemTy = Context.getBaseElementType(Ty); 806 } 807 808 if (!Ty->isVoidType() && 809 RequireCompleteType(TyBeginLoc, ElemTy, 810 PDiag(diag::err_invalid_incomplete_type_use) 811 << FullRange)) 812 return ExprError(); 813 814 if (RequireNonAbstractType(TyBeginLoc, Ty, 815 diag::err_allocation_of_abstract_type)) 816 return ExprError(); 817 818 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo); 819 InitializationKind Kind 820 = NumExprs ? ListInitialization 821 ? InitializationKind::CreateDirectList(TyBeginLoc) 822 : InitializationKind::CreateDirect(TyBeginLoc, 823 LParenLoc, RParenLoc) 824 : InitializationKind::CreateValue(TyBeginLoc, 825 LParenLoc, RParenLoc); 826 InitializationSequence InitSeq(*this, Entity, Kind, Exprs, NumExprs); 827 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, move(exprs)); 828 829 if (!Result.isInvalid() && ListInitialization && 830 isa<InitListExpr>(Result.get())) { 831 // If the list-initialization doesn't involve a constructor call, we'll get 832 // the initializer-list (with corrected type) back, but that's not what we 833 // want, since it will be treated as an initializer list in further 834 // processing. Explicitly insert a cast here. 835 InitListExpr *List = cast<InitListExpr>(Result.take()); 836 Result = Owned(CXXFunctionalCastExpr::Create(Context, List->getType(), 837 Expr::getValueKindForType(TInfo->getType()), 838 TInfo, TyBeginLoc, CK_NoOp, 839 List, /*Path=*/0, RParenLoc)); 840 } 841 842 // FIXME: Improve AST representation? 843 return move(Result); 844} 845 846/// doesUsualArrayDeleteWantSize - Answers whether the usual 847/// operator delete[] for the given type has a size_t parameter. 848static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc, 849 QualType allocType) { 850 const RecordType *record = 851 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>(); 852 if (!record) return false; 853 854 // Try to find an operator delete[] in class scope. 855 856 DeclarationName deleteName = 857 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete); 858 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName); 859 S.LookupQualifiedName(ops, record->getDecl()); 860 861 // We're just doing this for information. 862 ops.suppressDiagnostics(); 863 864 // Very likely: there's no operator delete[]. 865 if (ops.empty()) return false; 866 867 // If it's ambiguous, it should be illegal to call operator delete[] 868 // on this thing, so it doesn't matter if we allocate extra space or not. 869 if (ops.isAmbiguous()) return false; 870 871 LookupResult::Filter filter = ops.makeFilter(); 872 while (filter.hasNext()) { 873 NamedDecl *del = filter.next()->getUnderlyingDecl(); 874 875 // C++0x [basic.stc.dynamic.deallocation]p2: 876 // A template instance is never a usual deallocation function, 877 // regardless of its signature. 878 if (isa<FunctionTemplateDecl>(del)) { 879 filter.erase(); 880 continue; 881 } 882 883 // C++0x [basic.stc.dynamic.deallocation]p2: 884 // If class T does not declare [an operator delete[] with one 885 // parameter] but does declare a member deallocation function 886 // named operator delete[] with exactly two parameters, the 887 // second of which has type std::size_t, then this function 888 // is a usual deallocation function. 889 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) { 890 filter.erase(); 891 continue; 892 } 893 } 894 filter.done(); 895 896 if (!ops.isSingleResult()) return false; 897 898 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl()); 899 return (del->getNumParams() == 2); 900} 901 902/// \brief Parsed a C++ 'new' expression (C++ 5.3.4). 903 904/// E.g.: 905/// @code new (memory) int[size][4] @endcode 906/// or 907/// @code ::new Foo(23, "hello") @endcode 908/// 909/// \param StartLoc The first location of the expression. 910/// \param UseGlobal True if 'new' was prefixed with '::'. 911/// \param PlacementLParen Opening paren of the placement arguments. 912/// \param PlacementArgs Placement new arguments. 913/// \param PlacementRParen Closing paren of the placement arguments. 914/// \param TypeIdParens If the type is in parens, the source range. 915/// \param D The type to be allocated, as well as array dimensions. 916/// \param ConstructorLParen Opening paren of the constructor args, empty if 917/// initializer-list syntax is used. 918/// \param ConstructorArgs Constructor/initialization arguments. 919/// \param ConstructorRParen Closing paren of the constructor args. 920ExprResult 921Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal, 922 SourceLocation PlacementLParen, MultiExprArg PlacementArgs, 923 SourceLocation PlacementRParen, SourceRange TypeIdParens, 924 Declarator &D, Expr *Initializer) { 925 bool TypeContainsAuto = D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto; 926 927 Expr *ArraySize = 0; 928 // If the specified type is an array, unwrap it and save the expression. 929 if (D.getNumTypeObjects() > 0 && 930 D.getTypeObject(0).Kind == DeclaratorChunk::Array) { 931 DeclaratorChunk &Chunk = D.getTypeObject(0); 932 if (TypeContainsAuto) 933 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto) 934 << D.getSourceRange()); 935 if (Chunk.Arr.hasStatic) 936 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new) 937 << D.getSourceRange()); 938 if (!Chunk.Arr.NumElts) 939 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size) 940 << D.getSourceRange()); 941 942 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts); 943 D.DropFirstTypeObject(); 944 } 945 946 // Every dimension shall be of constant size. 947 if (ArraySize) { 948 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) { 949 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array) 950 break; 951 952 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr; 953 if (Expr *NumElts = (Expr *)Array.NumElts) { 954 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) { 955 Array.NumElts = VerifyIntegerConstantExpression(NumElts, 0, 956 PDiag(diag::err_new_array_nonconst)).take(); 957 if (!Array.NumElts) 958 return ExprError(); 959 } 960 } 961 } 962 } 963 964 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/0); 965 QualType AllocType = TInfo->getType(); 966 if (D.isInvalidType()) 967 return ExprError(); 968 969 SourceRange DirectInitRange; 970 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) 971 DirectInitRange = List->getSourceRange(); 972 973 return BuildCXXNew(StartLoc, UseGlobal, 974 PlacementLParen, 975 move(PlacementArgs), 976 PlacementRParen, 977 TypeIdParens, 978 AllocType, 979 TInfo, 980 ArraySize, 981 DirectInitRange, 982 Initializer, 983 TypeContainsAuto); 984} 985 986static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style, 987 Expr *Init) { 988 if (!Init) 989 return true; 990 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init)) 991 return PLE->getNumExprs() == 0; 992 if (isa<ImplicitValueInitExpr>(Init)) 993 return true; 994 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) 995 return !CCE->isListInitialization() && 996 CCE->getConstructor()->isDefaultConstructor(); 997 else if (Style == CXXNewExpr::ListInit) { 998 assert(isa<InitListExpr>(Init) && 999 "Shouldn't create list CXXConstructExprs for arrays."); 1000 return true; 1001 } 1002 return false; 1003} 1004 1005ExprResult 1006Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal, 1007 SourceLocation PlacementLParen, 1008 MultiExprArg PlacementArgs, 1009 SourceLocation PlacementRParen, 1010 SourceRange TypeIdParens, 1011 QualType AllocType, 1012 TypeSourceInfo *AllocTypeInfo, 1013 Expr *ArraySize, 1014 SourceRange DirectInitRange, 1015 Expr *Initializer, 1016 bool TypeMayContainAuto) { 1017 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange(); 1018 1019 CXXNewExpr::InitializationStyle initStyle; 1020 if (DirectInitRange.isValid()) { 1021 assert(Initializer && "Have parens but no initializer."); 1022 initStyle = CXXNewExpr::CallInit; 1023 } else if (Initializer && isa<InitListExpr>(Initializer)) 1024 initStyle = CXXNewExpr::ListInit; 1025 else { 1026 // In template instantiation, the initializer could be a CXXDefaultArgExpr 1027 // unwrapped from a CXXConstructExpr that was implicitly built. There is no 1028 // particularly sane way we can handle this (especially since it can even 1029 // occur for array new), so we throw the initializer away and have it be 1030 // rebuilt. 1031 if (Initializer && isa<CXXDefaultArgExpr>(Initializer)) 1032 Initializer = 0; 1033 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) || 1034 isa<CXXConstructExpr>(Initializer)) && 1035 "Initializer expression that cannot have been implicitly created."); 1036 initStyle = CXXNewExpr::NoInit; 1037 } 1038 1039 Expr **Inits = &Initializer; 1040 unsigned NumInits = Initializer ? 1 : 0; 1041 if (initStyle == CXXNewExpr::CallInit) { 1042 if (ParenListExpr *List = dyn_cast<ParenListExpr>(Initializer)) { 1043 Inits = List->getExprs(); 1044 NumInits = List->getNumExprs(); 1045 } else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Initializer)){ 1046 if (!isa<CXXTemporaryObjectExpr>(CCE)) { 1047 // Can happen in template instantiation. Since this is just an implicit 1048 // construction, we just take it apart and rebuild it. 1049 Inits = CCE->getArgs(); 1050 NumInits = CCE->getNumArgs(); 1051 } 1052 } 1053 } 1054 1055 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 1056 if (TypeMayContainAuto && AllocType->getContainedAutoType()) { 1057 if (initStyle == CXXNewExpr::NoInit || NumInits == 0) 1058 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg) 1059 << AllocType << TypeRange); 1060 if (initStyle == CXXNewExpr::ListInit) 1061 return ExprError(Diag(Inits[0]->getSourceRange().getBegin(), 1062 diag::err_auto_new_requires_parens) 1063 << AllocType << TypeRange); 1064 if (NumInits > 1) { 1065 Expr *FirstBad = Inits[1]; 1066 return ExprError(Diag(FirstBad->getSourceRange().getBegin(), 1067 diag::err_auto_new_ctor_multiple_expressions) 1068 << AllocType << TypeRange); 1069 } 1070 Expr *Deduce = Inits[0]; 1071 TypeSourceInfo *DeducedType = 0; 1072 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == 1073 DAR_Failed) 1074 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure) 1075 << AllocType << Deduce->getType() 1076 << TypeRange << Deduce->getSourceRange()); 1077 if (!DeducedType) 1078 return ExprError(); 1079 1080 AllocTypeInfo = DeducedType; 1081 AllocType = AllocTypeInfo->getType(); 1082 } 1083 1084 // Per C++0x [expr.new]p5, the type being constructed may be a 1085 // typedef of an array type. 1086 if (!ArraySize) { 1087 if (const ConstantArrayType *Array 1088 = Context.getAsConstantArrayType(AllocType)) { 1089 ArraySize = IntegerLiteral::Create(Context, Array->getSize(), 1090 Context.getSizeType(), 1091 TypeRange.getEnd()); 1092 AllocType = Array->getElementType(); 1093 } 1094 } 1095 1096 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange)) 1097 return ExprError(); 1098 1099 if (initStyle == CXXNewExpr::ListInit && isStdInitializerList(AllocType, 0)) { 1100 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(), 1101 diag::warn_dangling_std_initializer_list) 1102 << /*at end of FE*/0 << Inits[0]->getSourceRange(); 1103 } 1104 1105 // In ARC, infer 'retaining' for the allocated 1106 if (getLangOptions().ObjCAutoRefCount && 1107 AllocType.getObjCLifetime() == Qualifiers::OCL_None && 1108 AllocType->isObjCLifetimeType()) { 1109 AllocType = Context.getLifetimeQualifiedType(AllocType, 1110 AllocType->getObjCARCImplicitLifetime()); 1111 } 1112 1113 QualType ResultType = Context.getPointerType(AllocType); 1114 1115 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have 1116 // integral or enumeration type with a non-negative value." 1117 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped 1118 // enumeration type, or a class type for which a single non-explicit 1119 // conversion function to integral or unscoped enumeration type exists. 1120 if (ArraySize && !ArraySize->isTypeDependent()) { 1121 ExprResult ConvertedSize = ConvertToIntegralOrEnumerationType( 1122 StartLoc, ArraySize, 1123 PDiag(diag::err_array_size_not_integral) << getLangOptions().CPlusPlus0x, 1124 PDiag(diag::err_array_size_incomplete_type) 1125 << ArraySize->getSourceRange(), 1126 PDiag(diag::err_array_size_explicit_conversion), 1127 PDiag(diag::note_array_size_conversion), 1128 PDiag(diag::err_array_size_ambiguous_conversion), 1129 PDiag(diag::note_array_size_conversion), 1130 PDiag(getLangOptions().CPlusPlus0x ? 1131 diag::warn_cxx98_compat_array_size_conversion : 1132 diag::ext_array_size_conversion), 1133 /*AllowScopedEnumerations*/ false); 1134 if (ConvertedSize.isInvalid()) 1135 return ExprError(); 1136 1137 ArraySize = ConvertedSize.take(); 1138 QualType SizeType = ArraySize->getType(); 1139 if (!SizeType->isIntegralOrUnscopedEnumerationType()) 1140 return ExprError(); 1141 1142 // C++98 [expr.new]p7: 1143 // The expression in a direct-new-declarator shall have integral type 1144 // with a non-negative value. 1145 // 1146 // Let's see if this is a constant < 0. If so, we reject it out of 1147 // hand. Otherwise, if it's not a constant, we must have an unparenthesized 1148 // array type. 1149 // 1150 // Note: such a construct has well-defined semantics in C++11: it throws 1151 // std::bad_array_new_length. 1152 if (!ArraySize->isValueDependent()) { 1153 llvm::APSInt Value; 1154 // We've already performed any required implicit conversion to integer or 1155 // unscoped enumeration type. 1156 if (ArraySize->isIntegerConstantExpr(Value, Context)) { 1157 if (Value < llvm::APSInt( 1158 llvm::APInt::getNullValue(Value.getBitWidth()), 1159 Value.isUnsigned())) { 1160 if (getLangOptions().CPlusPlus0x) 1161 Diag(ArraySize->getSourceRange().getBegin(), 1162 diag::warn_typecheck_negative_array_new_size) 1163 << ArraySize->getSourceRange(); 1164 else 1165 return ExprError(Diag(ArraySize->getSourceRange().getBegin(), 1166 diag::err_typecheck_negative_array_size) 1167 << ArraySize->getSourceRange()); 1168 } else if (!AllocType->isDependentType()) { 1169 unsigned ActiveSizeBits = 1170 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value); 1171 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 1172 if (getLangOptions().CPlusPlus0x) 1173 Diag(ArraySize->getSourceRange().getBegin(), 1174 diag::warn_array_new_too_large) 1175 << Value.toString(10) 1176 << ArraySize->getSourceRange(); 1177 else 1178 return ExprError(Diag(ArraySize->getSourceRange().getBegin(), 1179 diag::err_array_too_large) 1180 << Value.toString(10) 1181 << ArraySize->getSourceRange()); 1182 } 1183 } 1184 } else if (TypeIdParens.isValid()) { 1185 // Can't have dynamic array size when the type-id is in parentheses. 1186 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst) 1187 << ArraySize->getSourceRange() 1188 << FixItHint::CreateRemoval(TypeIdParens.getBegin()) 1189 << FixItHint::CreateRemoval(TypeIdParens.getEnd()); 1190 1191 TypeIdParens = SourceRange(); 1192 } 1193 } 1194 1195 // ARC: warn about ABI issues. 1196 if (getLangOptions().ObjCAutoRefCount) { 1197 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1198 if (BaseAllocType.hasStrongOrWeakObjCLifetime()) 1199 Diag(StartLoc, diag::warn_err_new_delete_object_array) 1200 << 0 << BaseAllocType; 1201 } 1202 1203 // Note that we do *not* convert the argument in any way. It can 1204 // be signed, larger than size_t, whatever. 1205 } 1206 1207 FunctionDecl *OperatorNew = 0; 1208 FunctionDecl *OperatorDelete = 0; 1209 Expr **PlaceArgs = (Expr**)PlacementArgs.get(); 1210 unsigned NumPlaceArgs = PlacementArgs.size(); 1211 1212 if (!AllocType->isDependentType() && 1213 !Expr::hasAnyTypeDependentArguments( 1214 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs)) && 1215 FindAllocationFunctions(StartLoc, 1216 SourceRange(PlacementLParen, PlacementRParen), 1217 UseGlobal, AllocType, ArraySize, PlaceArgs, 1218 NumPlaceArgs, OperatorNew, OperatorDelete)) 1219 return ExprError(); 1220 1221 // If this is an array allocation, compute whether the usual array 1222 // deallocation function for the type has a size_t parameter. 1223 bool UsualArrayDeleteWantsSize = false; 1224 if (ArraySize && !AllocType->isDependentType()) 1225 UsualArrayDeleteWantsSize 1226 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType); 1227 1228 SmallVector<Expr *, 8> AllPlaceArgs; 1229 if (OperatorNew) { 1230 // Add default arguments, if any. 1231 const FunctionProtoType *Proto = 1232 OperatorNew->getType()->getAs<FunctionProtoType>(); 1233 VariadicCallType CallType = 1234 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 1235 1236 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, 1237 Proto, 1, PlaceArgs, NumPlaceArgs, 1238 AllPlaceArgs, CallType)) 1239 return ExprError(); 1240 1241 NumPlaceArgs = AllPlaceArgs.size(); 1242 if (NumPlaceArgs > 0) 1243 PlaceArgs = &AllPlaceArgs[0]; 1244 1245 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, 1246 PlaceArgs, NumPlaceArgs); 1247 1248 // FIXME: Missing call to CheckFunctionCall or equivalent 1249 } 1250 1251 // Warn if the type is over-aligned and is being allocated by global operator 1252 // new. 1253 if (NumPlaceArgs == 0 && OperatorNew && 1254 (OperatorNew->isImplicit() || 1255 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1256 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1257 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1258 if (Align > SuitableAlign) 1259 Diag(StartLoc, diag::warn_overaligned_type) 1260 << AllocType 1261 << unsigned(Align / Context.getCharWidth()) 1262 << unsigned(SuitableAlign / Context.getCharWidth()); 1263 } 1264 } 1265 1266 QualType InitType = AllocType; 1267 // Array 'new' can't have any initializers except empty parentheses. 1268 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1269 // dialect distinction. 1270 if (ResultType->isArrayType() || ArraySize) { 1271 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1272 SourceRange InitRange(Inits[0]->getLocStart(), 1273 Inits[NumInits - 1]->getLocEnd()); 1274 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1275 return ExprError(); 1276 } 1277 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1278 // We do the initialization typechecking against the array type 1279 // corresponding to the number of initializers + 1 (to also check 1280 // default-initialization). 1281 unsigned NumElements = ILE->getNumInits() + 1; 1282 InitType = Context.getConstantArrayType(AllocType, 1283 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1284 ArrayType::Normal, 0); 1285 } 1286 } 1287 1288 if (!AllocType->isDependentType() && 1289 !Expr::hasAnyTypeDependentArguments( 1290 llvm::makeArrayRef(Inits, NumInits))) { 1291 // C++11 [expr.new]p15: 1292 // A new-expression that creates an object of type T initializes that 1293 // object as follows: 1294 InitializationKind Kind 1295 // - If the new-initializer is omitted, the object is default- 1296 // initialized (8.5); if no initialization is performed, 1297 // the object has indeterminate value 1298 = initStyle == CXXNewExpr::NoInit 1299 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1300 // - Otherwise, the new-initializer is interpreted according to the 1301 // initialization rules of 8.5 for direct-initialization. 1302 : initStyle == CXXNewExpr::ListInit 1303 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1304 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1305 DirectInitRange.getBegin(), 1306 DirectInitRange.getEnd()); 1307 1308 InitializedEntity Entity 1309 = InitializedEntity::InitializeNew(StartLoc, InitType); 1310 InitializationSequence InitSeq(*this, Entity, Kind, Inits, NumInits); 1311 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1312 MultiExprArg(Inits, NumInits)); 1313 if (FullInit.isInvalid()) 1314 return ExprError(); 1315 1316 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1317 // we don't want the initialized object to be destructed. 1318 if (CXXBindTemporaryExpr *Binder = 1319 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1320 FullInit = Owned(Binder->getSubExpr()); 1321 1322 Initializer = FullInit.take(); 1323 } 1324 1325 // Mark the new and delete operators as referenced. 1326 if (OperatorNew) 1327 MarkFunctionReferenced(StartLoc, OperatorNew); 1328 if (OperatorDelete) 1329 MarkFunctionReferenced(StartLoc, OperatorDelete); 1330 1331 // C++0x [expr.new]p17: 1332 // If the new expression creates an array of objects of class type, 1333 // access and ambiguity control are done for the destructor. 1334 if (ArraySize && AllocType->isRecordType() && !AllocType->isDependentType()) { 1335 if (CXXDestructorDecl *dtor = LookupDestructor( 1336 cast<CXXRecordDecl>(AllocType->getAs<RecordType>()->getDecl()))) { 1337 MarkFunctionReferenced(StartLoc, dtor); 1338 CheckDestructorAccess(StartLoc, dtor, 1339 PDiag(diag::err_access_dtor) 1340 << Context.getBaseElementType(AllocType)); 1341 DiagnoseUseOfDecl(dtor, StartLoc); 1342 } 1343 } 1344 1345 PlacementArgs.release(); 1346 1347 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1348 OperatorDelete, 1349 UsualArrayDeleteWantsSize, 1350 PlaceArgs, NumPlaceArgs, TypeIdParens, 1351 ArraySize, initStyle, Initializer, 1352 ResultType, AllocTypeInfo, 1353 StartLoc, DirectInitRange)); 1354} 1355 1356/// \brief Checks that a type is suitable as the allocated type 1357/// in a new-expression. 1358bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1359 SourceRange R) { 1360 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1361 // abstract class type or array thereof. 1362 if (AllocType->isFunctionType()) 1363 return Diag(Loc, diag::err_bad_new_type) 1364 << AllocType << 0 << R; 1365 else if (AllocType->isReferenceType()) 1366 return Diag(Loc, diag::err_bad_new_type) 1367 << AllocType << 1 << R; 1368 else if (!AllocType->isDependentType() && 1369 RequireCompleteType(Loc, AllocType, 1370 PDiag(diag::err_new_incomplete_type) 1371 << R)) 1372 return true; 1373 else if (RequireNonAbstractType(Loc, AllocType, 1374 diag::err_allocation_of_abstract_type)) 1375 return true; 1376 else if (AllocType->isVariablyModifiedType()) 1377 return Diag(Loc, diag::err_variably_modified_new_type) 1378 << AllocType; 1379 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1380 return Diag(Loc, diag::err_address_space_qualified_new) 1381 << AllocType.getUnqualifiedType() << AddressSpace; 1382 else if (getLangOptions().ObjCAutoRefCount) { 1383 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1384 QualType BaseAllocType = Context.getBaseElementType(AT); 1385 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1386 BaseAllocType->isObjCLifetimeType()) 1387 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1388 << BaseAllocType; 1389 } 1390 } 1391 1392 return false; 1393} 1394 1395/// \brief Determine whether the given function is a non-placement 1396/// deallocation function. 1397static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1398 if (FD->isInvalidDecl()) 1399 return false; 1400 1401 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1402 return Method->isUsualDeallocationFunction(); 1403 1404 return ((FD->getOverloadedOperator() == OO_Delete || 1405 FD->getOverloadedOperator() == OO_Array_Delete) && 1406 FD->getNumParams() == 1); 1407} 1408 1409/// FindAllocationFunctions - Finds the overloads of operator new and delete 1410/// that are appropriate for the allocation. 1411bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1412 bool UseGlobal, QualType AllocType, 1413 bool IsArray, Expr **PlaceArgs, 1414 unsigned NumPlaceArgs, 1415 FunctionDecl *&OperatorNew, 1416 FunctionDecl *&OperatorDelete) { 1417 // --- Choosing an allocation function --- 1418 // C++ 5.3.4p8 - 14 & 18 1419 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1420 // in the scope of the allocated class. 1421 // 2) If an array size is given, look for operator new[], else look for 1422 // operator new. 1423 // 3) The first argument is always size_t. Append the arguments from the 1424 // placement form. 1425 1426 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1427 // We don't care about the actual value of this argument. 1428 // FIXME: Should the Sema create the expression and embed it in the syntax 1429 // tree? Or should the consumer just recalculate the value? 1430 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1431 Context.getTargetInfo().getPointerWidth(0)), 1432 Context.getSizeType(), 1433 SourceLocation()); 1434 AllocArgs[0] = &Size; 1435 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1436 1437 // C++ [expr.new]p8: 1438 // If the allocated type is a non-array type, the allocation 1439 // function's name is operator new and the deallocation function's 1440 // name is operator delete. If the allocated type is an array 1441 // type, the allocation function's name is operator new[] and the 1442 // deallocation function's name is operator delete[]. 1443 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1444 IsArray ? OO_Array_New : OO_New); 1445 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1446 IsArray ? OO_Array_Delete : OO_Delete); 1447 1448 QualType AllocElemType = Context.getBaseElementType(AllocType); 1449 1450 if (AllocElemType->isRecordType() && !UseGlobal) { 1451 CXXRecordDecl *Record 1452 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1453 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1454 AllocArgs.size(), Record, /*AllowMissing=*/true, 1455 OperatorNew)) 1456 return true; 1457 } 1458 if (!OperatorNew) { 1459 // Didn't find a member overload. Look for a global one. 1460 DeclareGlobalNewDelete(); 1461 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1462 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1463 AllocArgs.size(), TUDecl, /*AllowMissing=*/false, 1464 OperatorNew)) 1465 return true; 1466 } 1467 1468 // We don't need an operator delete if we're running under 1469 // -fno-exceptions. 1470 if (!getLangOptions().Exceptions) { 1471 OperatorDelete = 0; 1472 return false; 1473 } 1474 1475 // FindAllocationOverload can change the passed in arguments, so we need to 1476 // copy them back. 1477 if (NumPlaceArgs > 0) 1478 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1479 1480 // C++ [expr.new]p19: 1481 // 1482 // If the new-expression begins with a unary :: operator, the 1483 // deallocation function's name is looked up in the global 1484 // scope. Otherwise, if the allocated type is a class type T or an 1485 // array thereof, the deallocation function's name is looked up in 1486 // the scope of T. If this lookup fails to find the name, or if 1487 // the allocated type is not a class type or array thereof, the 1488 // deallocation function's name is looked up in the global scope. 1489 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1490 if (AllocElemType->isRecordType() && !UseGlobal) { 1491 CXXRecordDecl *RD 1492 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1493 LookupQualifiedName(FoundDelete, RD); 1494 } 1495 if (FoundDelete.isAmbiguous()) 1496 return true; // FIXME: clean up expressions? 1497 1498 if (FoundDelete.empty()) { 1499 DeclareGlobalNewDelete(); 1500 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1501 } 1502 1503 FoundDelete.suppressDiagnostics(); 1504 1505 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1506 1507 // Whether we're looking for a placement operator delete is dictated 1508 // by whether we selected a placement operator new, not by whether 1509 // we had explicit placement arguments. This matters for things like 1510 // struct A { void *operator new(size_t, int = 0); ... }; 1511 // A *a = new A() 1512 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1513 1514 if (isPlacementNew) { 1515 // C++ [expr.new]p20: 1516 // A declaration of a placement deallocation function matches the 1517 // declaration of a placement allocation function if it has the 1518 // same number of parameters and, after parameter transformations 1519 // (8.3.5), all parameter types except the first are 1520 // identical. [...] 1521 // 1522 // To perform this comparison, we compute the function type that 1523 // the deallocation function should have, and use that type both 1524 // for template argument deduction and for comparison purposes. 1525 // 1526 // FIXME: this comparison should ignore CC and the like. 1527 QualType ExpectedFunctionType; 1528 { 1529 const FunctionProtoType *Proto 1530 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1531 1532 SmallVector<QualType, 4> ArgTypes; 1533 ArgTypes.push_back(Context.VoidPtrTy); 1534 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1535 ArgTypes.push_back(Proto->getArgType(I)); 1536 1537 FunctionProtoType::ExtProtoInfo EPI; 1538 EPI.Variadic = Proto->isVariadic(); 1539 1540 ExpectedFunctionType 1541 = Context.getFunctionType(Context.VoidTy, ArgTypes.data(), 1542 ArgTypes.size(), EPI); 1543 } 1544 1545 for (LookupResult::iterator D = FoundDelete.begin(), 1546 DEnd = FoundDelete.end(); 1547 D != DEnd; ++D) { 1548 FunctionDecl *Fn = 0; 1549 if (FunctionTemplateDecl *FnTmpl 1550 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1551 // Perform template argument deduction to try to match the 1552 // expected function type. 1553 TemplateDeductionInfo Info(Context, StartLoc); 1554 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1555 continue; 1556 } else 1557 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1558 1559 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1560 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1561 } 1562 } else { 1563 // C++ [expr.new]p20: 1564 // [...] Any non-placement deallocation function matches a 1565 // non-placement allocation function. [...] 1566 for (LookupResult::iterator D = FoundDelete.begin(), 1567 DEnd = FoundDelete.end(); 1568 D != DEnd; ++D) { 1569 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1570 if (isNonPlacementDeallocationFunction(Fn)) 1571 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1572 } 1573 } 1574 1575 // C++ [expr.new]p20: 1576 // [...] If the lookup finds a single matching deallocation 1577 // function, that function will be called; otherwise, no 1578 // deallocation function will be called. 1579 if (Matches.size() == 1) { 1580 OperatorDelete = Matches[0].second; 1581 1582 // C++0x [expr.new]p20: 1583 // If the lookup finds the two-parameter form of a usual 1584 // deallocation function (3.7.4.2) and that function, considered 1585 // as a placement deallocation function, would have been 1586 // selected as a match for the allocation function, the program 1587 // is ill-formed. 1588 if (NumPlaceArgs && getLangOptions().CPlusPlus0x && 1589 isNonPlacementDeallocationFunction(OperatorDelete)) { 1590 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1591 << SourceRange(PlaceArgs[0]->getLocStart(), 1592 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1593 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1594 << DeleteName; 1595 } else { 1596 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1597 Matches[0].first); 1598 } 1599 } 1600 1601 return false; 1602} 1603 1604/// FindAllocationOverload - Find an fitting overload for the allocation 1605/// function in the specified scope. 1606bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1607 DeclarationName Name, Expr** Args, 1608 unsigned NumArgs, DeclContext *Ctx, 1609 bool AllowMissing, FunctionDecl *&Operator, 1610 bool Diagnose) { 1611 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1612 LookupQualifiedName(R, Ctx); 1613 if (R.empty()) { 1614 if (AllowMissing || !Diagnose) 1615 return false; 1616 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1617 << Name << Range; 1618 } 1619 1620 if (R.isAmbiguous()) 1621 return true; 1622 1623 R.suppressDiagnostics(); 1624 1625 OverloadCandidateSet Candidates(StartLoc); 1626 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1627 Alloc != AllocEnd; ++Alloc) { 1628 // Even member operator new/delete are implicitly treated as 1629 // static, so don't use AddMemberCandidate. 1630 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1631 1632 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1633 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1634 /*ExplicitTemplateArgs=*/0, 1635 llvm::makeArrayRef(Args, NumArgs), 1636 Candidates, 1637 /*SuppressUserConversions=*/false); 1638 continue; 1639 } 1640 1641 FunctionDecl *Fn = cast<FunctionDecl>(D); 1642 AddOverloadCandidate(Fn, Alloc.getPair(), 1643 llvm::makeArrayRef(Args, NumArgs), Candidates, 1644 /*SuppressUserConversions=*/false); 1645 } 1646 1647 // Do the resolution. 1648 OverloadCandidateSet::iterator Best; 1649 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1650 case OR_Success: { 1651 // Got one! 1652 FunctionDecl *FnDecl = Best->Function; 1653 MarkFunctionReferenced(StartLoc, FnDecl); 1654 // The first argument is size_t, and the first parameter must be size_t, 1655 // too. This is checked on declaration and can be assumed. (It can't be 1656 // asserted on, though, since invalid decls are left in there.) 1657 // Watch out for variadic allocator function. 1658 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1659 for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) { 1660 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1661 FnDecl->getParamDecl(i)); 1662 1663 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1664 return true; 1665 1666 ExprResult Result 1667 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1668 if (Result.isInvalid()) 1669 return true; 1670 1671 Args[i] = Result.takeAs<Expr>(); 1672 } 1673 1674 Operator = FnDecl; 1675 1676 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), 1677 Best->FoundDecl, Diagnose) == AR_inaccessible) 1678 return true; 1679 1680 return false; 1681 } 1682 1683 case OR_No_Viable_Function: 1684 if (Diagnose) { 1685 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1686 << Name << Range; 1687 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1688 llvm::makeArrayRef(Args, NumArgs)); 1689 } 1690 return true; 1691 1692 case OR_Ambiguous: 1693 if (Diagnose) { 1694 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1695 << Name << Range; 1696 Candidates.NoteCandidates(*this, OCD_ViableCandidates, 1697 llvm::makeArrayRef(Args, NumArgs)); 1698 } 1699 return true; 1700 1701 case OR_Deleted: { 1702 if (Diagnose) { 1703 Diag(StartLoc, diag::err_ovl_deleted_call) 1704 << Best->Function->isDeleted() 1705 << Name 1706 << getDeletedOrUnavailableSuffix(Best->Function) 1707 << Range; 1708 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1709 llvm::makeArrayRef(Args, NumArgs)); 1710 } 1711 return true; 1712 } 1713 } 1714 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1715} 1716 1717 1718/// DeclareGlobalNewDelete - Declare the global forms of operator new and 1719/// delete. These are: 1720/// @code 1721/// // C++03: 1722/// void* operator new(std::size_t) throw(std::bad_alloc); 1723/// void* operator new[](std::size_t) throw(std::bad_alloc); 1724/// void operator delete(void *) throw(); 1725/// void operator delete[](void *) throw(); 1726/// // C++0x: 1727/// void* operator new(std::size_t); 1728/// void* operator new[](std::size_t); 1729/// void operator delete(void *); 1730/// void operator delete[](void *); 1731/// @endcode 1732/// C++0x operator delete is implicitly noexcept. 1733/// Note that the placement and nothrow forms of new are *not* implicitly 1734/// declared. Their use requires including \<new\>. 1735void Sema::DeclareGlobalNewDelete() { 1736 if (GlobalNewDeleteDeclared) 1737 return; 1738 1739 // C++ [basic.std.dynamic]p2: 1740 // [...] The following allocation and deallocation functions (18.4) are 1741 // implicitly declared in global scope in each translation unit of a 1742 // program 1743 // 1744 // C++03: 1745 // void* operator new(std::size_t) throw(std::bad_alloc); 1746 // void* operator new[](std::size_t) throw(std::bad_alloc); 1747 // void operator delete(void*) throw(); 1748 // void operator delete[](void*) throw(); 1749 // C++0x: 1750 // void* operator new(std::size_t); 1751 // void* operator new[](std::size_t); 1752 // void operator delete(void*); 1753 // void operator delete[](void*); 1754 // 1755 // These implicit declarations introduce only the function names operator 1756 // new, operator new[], operator delete, operator delete[]. 1757 // 1758 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1759 // "std" or "bad_alloc" as necessary to form the exception specification. 1760 // However, we do not make these implicit declarations visible to name 1761 // lookup. 1762 // Note that the C++0x versions of operator delete are deallocation functions, 1763 // and thus are implicitly noexcept. 1764 if (!StdBadAlloc && !getLangOptions().CPlusPlus0x) { 1765 // The "std::bad_alloc" class has not yet been declared, so build it 1766 // implicitly. 1767 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1768 getOrCreateStdNamespace(), 1769 SourceLocation(), SourceLocation(), 1770 &PP.getIdentifierTable().get("bad_alloc"), 1771 0); 1772 getStdBadAlloc()->setImplicit(true); 1773 } 1774 1775 GlobalNewDeleteDeclared = true; 1776 1777 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1778 QualType SizeT = Context.getSizeType(); 1779 bool AssumeSaneOperatorNew = getLangOptions().AssumeSaneOperatorNew; 1780 1781 DeclareGlobalAllocationFunction( 1782 Context.DeclarationNames.getCXXOperatorName(OO_New), 1783 VoidPtr, SizeT, AssumeSaneOperatorNew); 1784 DeclareGlobalAllocationFunction( 1785 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1786 VoidPtr, SizeT, AssumeSaneOperatorNew); 1787 DeclareGlobalAllocationFunction( 1788 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1789 Context.VoidTy, VoidPtr); 1790 DeclareGlobalAllocationFunction( 1791 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1792 Context.VoidTy, VoidPtr); 1793} 1794 1795/// DeclareGlobalAllocationFunction - Declares a single implicit global 1796/// allocation function if it doesn't already exist. 1797void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1798 QualType Return, QualType Argument, 1799 bool AddMallocAttr) { 1800 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1801 1802 // Check if this function is already declared. 1803 { 1804 DeclContext::lookup_iterator Alloc, AllocEnd; 1805 for (llvm::tie(Alloc, AllocEnd) = GlobalCtx->lookup(Name); 1806 Alloc != AllocEnd; ++Alloc) { 1807 // Only look at non-template functions, as it is the predefined, 1808 // non-templated allocation function we are trying to declare here. 1809 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1810 QualType InitialParamType = 1811 Context.getCanonicalType( 1812 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1813 // FIXME: Do we need to check for default arguments here? 1814 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1815 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1816 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1817 return; 1818 } 1819 } 1820 } 1821 } 1822 1823 QualType BadAllocType; 1824 bool HasBadAllocExceptionSpec 1825 = (Name.getCXXOverloadedOperator() == OO_New || 1826 Name.getCXXOverloadedOperator() == OO_Array_New); 1827 if (HasBadAllocExceptionSpec && !getLangOptions().CPlusPlus0x) { 1828 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1829 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1830 } 1831 1832 FunctionProtoType::ExtProtoInfo EPI; 1833 if (HasBadAllocExceptionSpec) { 1834 if (!getLangOptions().CPlusPlus0x) { 1835 EPI.ExceptionSpecType = EST_Dynamic; 1836 EPI.NumExceptions = 1; 1837 EPI.Exceptions = &BadAllocType; 1838 } 1839 } else { 1840 EPI.ExceptionSpecType = getLangOptions().CPlusPlus0x ? 1841 EST_BasicNoexcept : EST_DynamicNone; 1842 } 1843 1844 QualType FnType = Context.getFunctionType(Return, &Argument, 1, EPI); 1845 FunctionDecl *Alloc = 1846 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1847 SourceLocation(), Name, 1848 FnType, /*TInfo=*/0, SC_None, 1849 SC_None, false, true); 1850 Alloc->setImplicit(); 1851 1852 if (AddMallocAttr) 1853 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1854 1855 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1856 SourceLocation(), 0, 1857 Argument, /*TInfo=*/0, 1858 SC_None, SC_None, 0); 1859 Alloc->setParams(Param); 1860 1861 // FIXME: Also add this declaration to the IdentifierResolver, but 1862 // make sure it is at the end of the chain to coincide with the 1863 // global scope. 1864 Context.getTranslationUnitDecl()->addDecl(Alloc); 1865} 1866 1867bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1868 DeclarationName Name, 1869 FunctionDecl* &Operator, bool Diagnose) { 1870 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1871 // Try to find operator delete/operator delete[] in class scope. 1872 LookupQualifiedName(Found, RD); 1873 1874 if (Found.isAmbiguous()) 1875 return true; 1876 1877 Found.suppressDiagnostics(); 1878 1879 SmallVector<DeclAccessPair,4> Matches; 1880 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1881 F != FEnd; ++F) { 1882 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1883 1884 // Ignore template operator delete members from the check for a usual 1885 // deallocation function. 1886 if (isa<FunctionTemplateDecl>(ND)) 1887 continue; 1888 1889 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1890 Matches.push_back(F.getPair()); 1891 } 1892 1893 // There's exactly one suitable operator; pick it. 1894 if (Matches.size() == 1) { 1895 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 1896 1897 if (Operator->isDeleted()) { 1898 if (Diagnose) { 1899 Diag(StartLoc, diag::err_deleted_function_use); 1900 Diag(Operator->getLocation(), diag::note_unavailable_here) 1901 << /*function*/ 1 << /*deleted*/ 1; 1902 } 1903 return true; 1904 } 1905 1906 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 1907 Matches[0], Diagnose) == AR_inaccessible) 1908 return true; 1909 1910 return false; 1911 1912 // We found multiple suitable operators; complain about the ambiguity. 1913 } else if (!Matches.empty()) { 1914 if (Diagnose) { 1915 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 1916 << Name << RD; 1917 1918 for (SmallVectorImpl<DeclAccessPair>::iterator 1919 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 1920 Diag((*F)->getUnderlyingDecl()->getLocation(), 1921 diag::note_member_declared_here) << Name; 1922 } 1923 return true; 1924 } 1925 1926 // We did find operator delete/operator delete[] declarations, but 1927 // none of them were suitable. 1928 if (!Found.empty()) { 1929 if (Diagnose) { 1930 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 1931 << Name << RD; 1932 1933 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1934 F != FEnd; ++F) 1935 Diag((*F)->getUnderlyingDecl()->getLocation(), 1936 diag::note_member_declared_here) << Name; 1937 } 1938 return true; 1939 } 1940 1941 // Look for a global declaration. 1942 DeclareGlobalNewDelete(); 1943 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1944 1945 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 1946 Expr* DeallocArgs[1]; 1947 DeallocArgs[0] = &Null; 1948 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 1949 DeallocArgs, 1, TUDecl, !Diagnose, 1950 Operator, Diagnose)) 1951 return true; 1952 1953 assert(Operator && "Did not find a deallocation function!"); 1954 return false; 1955} 1956 1957/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 1958/// @code ::delete ptr; @endcode 1959/// or 1960/// @code delete [] ptr; @endcode 1961ExprResult 1962Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 1963 bool ArrayForm, Expr *ExE) { 1964 // C++ [expr.delete]p1: 1965 // The operand shall have a pointer type, or a class type having a single 1966 // conversion function to a pointer type. The result has type void. 1967 // 1968 // DR599 amends "pointer type" to "pointer to object type" in both cases. 1969 1970 ExprResult Ex = Owned(ExE); 1971 FunctionDecl *OperatorDelete = 0; 1972 bool ArrayFormAsWritten = ArrayForm; 1973 bool UsualArrayDeleteWantsSize = false; 1974 1975 if (!Ex.get()->isTypeDependent()) { 1976 QualType Type = Ex.get()->getType(); 1977 1978 if (const RecordType *Record = Type->getAs<RecordType>()) { 1979 if (RequireCompleteType(StartLoc, Type, 1980 PDiag(diag::err_delete_incomplete_class_type))) 1981 return ExprError(); 1982 1983 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 1984 1985 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 1986 const UnresolvedSetImpl *Conversions = RD->getVisibleConversionFunctions(); 1987 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 1988 E = Conversions->end(); I != E; ++I) { 1989 NamedDecl *D = I.getDecl(); 1990 if (isa<UsingShadowDecl>(D)) 1991 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1992 1993 // Skip over templated conversion functions; they aren't considered. 1994 if (isa<FunctionTemplateDecl>(D)) 1995 continue; 1996 1997 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 1998 1999 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 2000 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 2001 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 2002 ObjectPtrConversions.push_back(Conv); 2003 } 2004 if (ObjectPtrConversions.size() == 1) { 2005 // We have a single conversion to a pointer-to-object type. Perform 2006 // that conversion. 2007 // TODO: don't redo the conversion calculation. 2008 ExprResult Res = 2009 PerformImplicitConversion(Ex.get(), 2010 ObjectPtrConversions.front()->getConversionType(), 2011 AA_Converting); 2012 if (Res.isUsable()) { 2013 Ex = move(Res); 2014 Type = Ex.get()->getType(); 2015 } 2016 } 2017 else if (ObjectPtrConversions.size() > 1) { 2018 Diag(StartLoc, diag::err_ambiguous_delete_operand) 2019 << Type << Ex.get()->getSourceRange(); 2020 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 2021 NoteOverloadCandidate(ObjectPtrConversions[i]); 2022 return ExprError(); 2023 } 2024 } 2025 2026 if (!Type->isPointerType()) 2027 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2028 << Type << Ex.get()->getSourceRange()); 2029 2030 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2031 QualType PointeeElem = Context.getBaseElementType(Pointee); 2032 2033 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2034 return Diag(Ex.get()->getLocStart(), 2035 diag::err_address_space_qualified_delete) 2036 << Pointee.getUnqualifiedType() << AddressSpace; 2037 2038 CXXRecordDecl *PointeeRD = 0; 2039 if (Pointee->isVoidType() && !isSFINAEContext()) { 2040 // The C++ standard bans deleting a pointer to a non-object type, which 2041 // effectively bans deletion of "void*". However, most compilers support 2042 // this, so we treat it as a warning unless we're in a SFINAE context. 2043 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2044 << Type << Ex.get()->getSourceRange(); 2045 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2046 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2047 << Type << Ex.get()->getSourceRange()); 2048 } else if (!Pointee->isDependentType()) { 2049 if (!RequireCompleteType(StartLoc, Pointee, 2050 PDiag(diag::warn_delete_incomplete) 2051 << Ex.get()->getSourceRange())) { 2052 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2053 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2054 } 2055 } 2056 2057 // Perform lvalue-to-rvalue cast, if needed. 2058 Ex = DefaultLvalueConversion(Ex.take()); 2059 2060 // C++ [expr.delete]p2: 2061 // [Note: a pointer to a const type can be the operand of a 2062 // delete-expression; it is not necessary to cast away the constness 2063 // (5.2.11) of the pointer expression before it is used as the operand 2064 // of the delete-expression. ] 2065 if (!Context.hasSameType(Ex.get()->getType(), Context.VoidPtrTy)) 2066 Ex = Owned(ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2067 CK_BitCast, Ex.take(), 0, VK_RValue)); 2068 2069 if (Pointee->isArrayType() && !ArrayForm) { 2070 Diag(StartLoc, diag::warn_delete_array_type) 2071 << Type << Ex.get()->getSourceRange() 2072 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2073 ArrayForm = true; 2074 } 2075 2076 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2077 ArrayForm ? OO_Array_Delete : OO_Delete); 2078 2079 if (PointeeRD) { 2080 if (!UseGlobal && 2081 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2082 OperatorDelete)) 2083 return ExprError(); 2084 2085 // If we're allocating an array of records, check whether the 2086 // usual operator delete[] has a size_t parameter. 2087 if (ArrayForm) { 2088 // If the user specifically asked to use the global allocator, 2089 // we'll need to do the lookup into the class. 2090 if (UseGlobal) 2091 UsualArrayDeleteWantsSize = 2092 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2093 2094 // Otherwise, the usual operator delete[] should be the 2095 // function we just found. 2096 else if (isa<CXXMethodDecl>(OperatorDelete)) 2097 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2098 } 2099 2100 if (!PointeeRD->hasIrrelevantDestructor()) 2101 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2102 MarkFunctionReferenced(StartLoc, 2103 const_cast<CXXDestructorDecl*>(Dtor)); 2104 DiagnoseUseOfDecl(Dtor, StartLoc); 2105 } 2106 2107 // C++ [expr.delete]p3: 2108 // In the first alternative (delete object), if the static type of the 2109 // object to be deleted is different from its dynamic type, the static 2110 // type shall be a base class of the dynamic type of the object to be 2111 // deleted and the static type shall have a virtual destructor or the 2112 // behavior is undefined. 2113 // 2114 // Note: a final class cannot be derived from, no issue there 2115 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2116 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2117 if (dtor && !dtor->isVirtual()) { 2118 if (PointeeRD->isAbstract()) { 2119 // If the class is abstract, we warn by default, because we're 2120 // sure the code has undefined behavior. 2121 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2122 << PointeeElem; 2123 } else if (!ArrayForm) { 2124 // Otherwise, if this is not an array delete, it's a bit suspect, 2125 // but not necessarily wrong. 2126 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2127 } 2128 } 2129 } 2130 2131 } else if (getLangOptions().ObjCAutoRefCount && 2132 PointeeElem->isObjCLifetimeType() && 2133 (PointeeElem.getObjCLifetime() == Qualifiers::OCL_Strong || 2134 PointeeElem.getObjCLifetime() == Qualifiers::OCL_Weak) && 2135 ArrayForm) { 2136 Diag(StartLoc, diag::warn_err_new_delete_object_array) 2137 << 1 << PointeeElem; 2138 } 2139 2140 if (!OperatorDelete) { 2141 // Look for a global declaration. 2142 DeclareGlobalNewDelete(); 2143 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2144 Expr *Arg = Ex.get(); 2145 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2146 &Arg, 1, TUDecl, /*AllowMissing=*/false, 2147 OperatorDelete)) 2148 return ExprError(); 2149 } 2150 2151 MarkFunctionReferenced(StartLoc, OperatorDelete); 2152 2153 // Check access and ambiguity of operator delete and destructor. 2154 if (PointeeRD) { 2155 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2156 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2157 PDiag(diag::err_access_dtor) << PointeeElem); 2158 } 2159 } 2160 2161 } 2162 2163 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2164 ArrayFormAsWritten, 2165 UsualArrayDeleteWantsSize, 2166 OperatorDelete, Ex.take(), StartLoc)); 2167} 2168 2169/// \brief Check the use of the given variable as a C++ condition in an if, 2170/// while, do-while, or switch statement. 2171ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2172 SourceLocation StmtLoc, 2173 bool ConvertToBoolean) { 2174 QualType T = ConditionVar->getType(); 2175 2176 // C++ [stmt.select]p2: 2177 // The declarator shall not specify a function or an array. 2178 if (T->isFunctionType()) 2179 return ExprError(Diag(ConditionVar->getLocation(), 2180 diag::err_invalid_use_of_function_type) 2181 << ConditionVar->getSourceRange()); 2182 else if (T->isArrayType()) 2183 return ExprError(Diag(ConditionVar->getLocation(), 2184 diag::err_invalid_use_of_array_type) 2185 << ConditionVar->getSourceRange()); 2186 2187 ExprResult Condition = 2188 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2189 SourceLocation(), 2190 ConditionVar, 2191 ConditionVar->getLocation(), 2192 ConditionVar->getType().getNonReferenceType(), 2193 VK_LValue)); 2194 2195 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2196 2197 if (ConvertToBoolean) { 2198 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2199 if (Condition.isInvalid()) 2200 return ExprError(); 2201 } 2202 2203 return move(Condition); 2204} 2205 2206/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2207ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2208 // C++ 6.4p4: 2209 // The value of a condition that is an initialized declaration in a statement 2210 // other than a switch statement is the value of the declared variable 2211 // implicitly converted to type bool. If that conversion is ill-formed, the 2212 // program is ill-formed. 2213 // The value of a condition that is an expression is the value of the 2214 // expression, implicitly converted to bool. 2215 // 2216 return PerformContextuallyConvertToBool(CondExpr); 2217} 2218 2219/// Helper function to determine whether this is the (deprecated) C++ 2220/// conversion from a string literal to a pointer to non-const char or 2221/// non-const wchar_t (for narrow and wide string literals, 2222/// respectively). 2223bool 2224Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2225 // Look inside the implicit cast, if it exists. 2226 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2227 From = Cast->getSubExpr(); 2228 2229 // A string literal (2.13.4) that is not a wide string literal can 2230 // be converted to an rvalue of type "pointer to char"; a wide 2231 // string literal can be converted to an rvalue of type "pointer 2232 // to wchar_t" (C++ 4.2p2). 2233 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2234 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2235 if (const BuiltinType *ToPointeeType 2236 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2237 // This conversion is considered only when there is an 2238 // explicit appropriate pointer target type (C++ 4.2p2). 2239 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2240 switch (StrLit->getKind()) { 2241 case StringLiteral::UTF8: 2242 case StringLiteral::UTF16: 2243 case StringLiteral::UTF32: 2244 // We don't allow UTF literals to be implicitly converted 2245 break; 2246 case StringLiteral::Ascii: 2247 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2248 ToPointeeType->getKind() == BuiltinType::Char_S); 2249 case StringLiteral::Wide: 2250 return ToPointeeType->isWideCharType(); 2251 } 2252 } 2253 } 2254 2255 return false; 2256} 2257 2258static ExprResult BuildCXXCastArgument(Sema &S, 2259 SourceLocation CastLoc, 2260 QualType Ty, 2261 CastKind Kind, 2262 CXXMethodDecl *Method, 2263 DeclAccessPair FoundDecl, 2264 bool HadMultipleCandidates, 2265 Expr *From) { 2266 switch (Kind) { 2267 default: llvm_unreachable("Unhandled cast kind!"); 2268 case CK_ConstructorConversion: { 2269 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2270 ASTOwningVector<Expr*> ConstructorArgs(S); 2271 2272 if (S.CompleteConstructorCall(Constructor, 2273 MultiExprArg(&From, 1), 2274 CastLoc, ConstructorArgs)) 2275 return ExprError(); 2276 2277 S.CheckConstructorAccess(CastLoc, Constructor, Constructor->getAccess(), 2278 S.PDiag(diag::err_access_ctor)); 2279 2280 ExprResult Result 2281 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2282 move_arg(ConstructorArgs), 2283 HadMultipleCandidates, /*ZeroInit*/ false, 2284 CXXConstructExpr::CK_Complete, SourceRange()); 2285 if (Result.isInvalid()) 2286 return ExprError(); 2287 2288 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2289 } 2290 2291 case CK_UserDefinedConversion: { 2292 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2293 2294 // Create an implicit call expr that calls it. 2295 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Method, 2296 HadMultipleCandidates); 2297 if (Result.isInvalid()) 2298 return ExprError(); 2299 // Record usage of conversion in an implicit cast. 2300 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2301 Result.get()->getType(), 2302 CK_UserDefinedConversion, 2303 Result.get(), 0, 2304 Result.get()->getValueKind())); 2305 2306 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2307 2308 return S.MaybeBindToTemporary(Result.get()); 2309 } 2310 } 2311} 2312 2313/// PerformImplicitConversion - Perform an implicit conversion of the 2314/// expression From to the type ToType using the pre-computed implicit 2315/// conversion sequence ICS. Returns the converted 2316/// expression. Action is the kind of conversion we're performing, 2317/// used in the error message. 2318ExprResult 2319Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2320 const ImplicitConversionSequence &ICS, 2321 AssignmentAction Action, 2322 CheckedConversionKind CCK) { 2323 switch (ICS.getKind()) { 2324 case ImplicitConversionSequence::StandardConversion: { 2325 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2326 Action, CCK); 2327 if (Res.isInvalid()) 2328 return ExprError(); 2329 From = Res.take(); 2330 break; 2331 } 2332 2333 case ImplicitConversionSequence::UserDefinedConversion: { 2334 2335 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2336 CastKind CastKind; 2337 QualType BeforeToType; 2338 assert(FD && "FIXME: aggregate initialization from init list"); 2339 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2340 CastKind = CK_UserDefinedConversion; 2341 2342 // If the user-defined conversion is specified by a conversion function, 2343 // the initial standard conversion sequence converts the source type to 2344 // the implicit object parameter of the conversion function. 2345 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2346 } else { 2347 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2348 CastKind = CK_ConstructorConversion; 2349 // Do no conversion if dealing with ... for the first conversion. 2350 if (!ICS.UserDefined.EllipsisConversion) { 2351 // If the user-defined conversion is specified by a constructor, the 2352 // initial standard conversion sequence converts the source type to the 2353 // type required by the argument of the constructor 2354 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2355 } 2356 } 2357 // Watch out for elipsis conversion. 2358 if (!ICS.UserDefined.EllipsisConversion) { 2359 ExprResult Res = 2360 PerformImplicitConversion(From, BeforeToType, 2361 ICS.UserDefined.Before, AA_Converting, 2362 CCK); 2363 if (Res.isInvalid()) 2364 return ExprError(); 2365 From = Res.take(); 2366 } 2367 2368 ExprResult CastArg 2369 = BuildCXXCastArgument(*this, 2370 From->getLocStart(), 2371 ToType.getNonReferenceType(), 2372 CastKind, cast<CXXMethodDecl>(FD), 2373 ICS.UserDefined.FoundConversionFunction, 2374 ICS.UserDefined.HadMultipleCandidates, 2375 From); 2376 2377 if (CastArg.isInvalid()) 2378 return ExprError(); 2379 2380 From = CastArg.take(); 2381 2382 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2383 AA_Converting, CCK); 2384 } 2385 2386 case ImplicitConversionSequence::AmbiguousConversion: 2387 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2388 PDiag(diag::err_typecheck_ambiguous_condition) 2389 << From->getSourceRange()); 2390 return ExprError(); 2391 2392 case ImplicitConversionSequence::EllipsisConversion: 2393 llvm_unreachable("Cannot perform an ellipsis conversion"); 2394 2395 case ImplicitConversionSequence::BadConversion: 2396 return ExprError(); 2397 } 2398 2399 // Everything went well. 2400 return Owned(From); 2401} 2402 2403/// PerformImplicitConversion - Perform an implicit conversion of the 2404/// expression From to the type ToType by following the standard 2405/// conversion sequence SCS. Returns the converted 2406/// expression. Flavor is the context in which we're performing this 2407/// conversion, for use in error messages. 2408ExprResult 2409Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2410 const StandardConversionSequence& SCS, 2411 AssignmentAction Action, 2412 CheckedConversionKind CCK) { 2413 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2414 2415 // Overall FIXME: we are recomputing too many types here and doing far too 2416 // much extra work. What this means is that we need to keep track of more 2417 // information that is computed when we try the implicit conversion initially, 2418 // so that we don't need to recompute anything here. 2419 QualType FromType = From->getType(); 2420 2421 if (SCS.CopyConstructor) { 2422 // FIXME: When can ToType be a reference type? 2423 assert(!ToType->isReferenceType()); 2424 if (SCS.Second == ICK_Derived_To_Base) { 2425 ASTOwningVector<Expr*> ConstructorArgs(*this); 2426 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2427 MultiExprArg(*this, &From, 1), 2428 /*FIXME:ConstructLoc*/SourceLocation(), 2429 ConstructorArgs)) 2430 return ExprError(); 2431 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2432 ToType, SCS.CopyConstructor, 2433 move_arg(ConstructorArgs), 2434 /*HadMultipleCandidates*/ false, 2435 /*ZeroInit*/ false, 2436 CXXConstructExpr::CK_Complete, 2437 SourceRange()); 2438 } 2439 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2440 ToType, SCS.CopyConstructor, 2441 MultiExprArg(*this, &From, 1), 2442 /*HadMultipleCandidates*/ false, 2443 /*ZeroInit*/ false, 2444 CXXConstructExpr::CK_Complete, 2445 SourceRange()); 2446 } 2447 2448 // Resolve overloaded function references. 2449 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2450 DeclAccessPair Found; 2451 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2452 true, Found); 2453 if (!Fn) 2454 return ExprError(); 2455 2456 if (DiagnoseUseOfDecl(Fn, From->getSourceRange().getBegin())) 2457 return ExprError(); 2458 2459 From = FixOverloadedFunctionReference(From, Found, Fn); 2460 FromType = From->getType(); 2461 } 2462 2463 // Perform the first implicit conversion. 2464 switch (SCS.First) { 2465 case ICK_Identity: 2466 // Nothing to do. 2467 break; 2468 2469 case ICK_Lvalue_To_Rvalue: { 2470 assert(From->getObjectKind() != OK_ObjCProperty); 2471 FromType = FromType.getUnqualifiedType(); 2472 ExprResult FromRes = DefaultLvalueConversion(From); 2473 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2474 From = FromRes.take(); 2475 break; 2476 } 2477 2478 case ICK_Array_To_Pointer: 2479 FromType = Context.getArrayDecayedType(FromType); 2480 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2481 VK_RValue, /*BasePath=*/0, CCK).take(); 2482 break; 2483 2484 case ICK_Function_To_Pointer: 2485 FromType = Context.getPointerType(FromType); 2486 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2487 VK_RValue, /*BasePath=*/0, CCK).take(); 2488 break; 2489 2490 default: 2491 llvm_unreachable("Improper first standard conversion"); 2492 } 2493 2494 // Perform the second implicit conversion 2495 switch (SCS.Second) { 2496 case ICK_Identity: 2497 // If both sides are functions (or pointers/references to them), there could 2498 // be incompatible exception declarations. 2499 if (CheckExceptionSpecCompatibility(From, ToType)) 2500 return ExprError(); 2501 // Nothing else to do. 2502 break; 2503 2504 case ICK_NoReturn_Adjustment: 2505 // If both sides are functions (or pointers/references to them), there could 2506 // be incompatible exception declarations. 2507 if (CheckExceptionSpecCompatibility(From, ToType)) 2508 return ExprError(); 2509 2510 From = ImpCastExprToType(From, ToType, CK_NoOp, 2511 VK_RValue, /*BasePath=*/0, CCK).take(); 2512 break; 2513 2514 case ICK_Integral_Promotion: 2515 case ICK_Integral_Conversion: 2516 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2517 VK_RValue, /*BasePath=*/0, CCK).take(); 2518 break; 2519 2520 case ICK_Floating_Promotion: 2521 case ICK_Floating_Conversion: 2522 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2523 VK_RValue, /*BasePath=*/0, CCK).take(); 2524 break; 2525 2526 case ICK_Complex_Promotion: 2527 case ICK_Complex_Conversion: { 2528 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2529 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2530 CastKind CK; 2531 if (FromEl->isRealFloatingType()) { 2532 if (ToEl->isRealFloatingType()) 2533 CK = CK_FloatingComplexCast; 2534 else 2535 CK = CK_FloatingComplexToIntegralComplex; 2536 } else if (ToEl->isRealFloatingType()) { 2537 CK = CK_IntegralComplexToFloatingComplex; 2538 } else { 2539 CK = CK_IntegralComplexCast; 2540 } 2541 From = ImpCastExprToType(From, ToType, CK, 2542 VK_RValue, /*BasePath=*/0, CCK).take(); 2543 break; 2544 } 2545 2546 case ICK_Floating_Integral: 2547 if (ToType->isRealFloatingType()) 2548 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2549 VK_RValue, /*BasePath=*/0, CCK).take(); 2550 else 2551 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2552 VK_RValue, /*BasePath=*/0, CCK).take(); 2553 break; 2554 2555 case ICK_Compatible_Conversion: 2556 From = ImpCastExprToType(From, ToType, CK_NoOp, 2557 VK_RValue, /*BasePath=*/0, CCK).take(); 2558 break; 2559 2560 case ICK_Writeback_Conversion: 2561 case ICK_Pointer_Conversion: { 2562 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2563 // Diagnose incompatible Objective-C conversions 2564 if (Action == AA_Initializing || Action == AA_Assigning) 2565 Diag(From->getSourceRange().getBegin(), 2566 diag::ext_typecheck_convert_incompatible_pointer) 2567 << ToType << From->getType() << Action 2568 << From->getSourceRange() << 0; 2569 else 2570 Diag(From->getSourceRange().getBegin(), 2571 diag::ext_typecheck_convert_incompatible_pointer) 2572 << From->getType() << ToType << Action 2573 << From->getSourceRange() << 0; 2574 2575 if (From->getType()->isObjCObjectPointerType() && 2576 ToType->isObjCObjectPointerType()) 2577 EmitRelatedResultTypeNote(From); 2578 } 2579 else if (getLangOptions().ObjCAutoRefCount && 2580 !CheckObjCARCUnavailableWeakConversion(ToType, 2581 From->getType())) { 2582 if (Action == AA_Initializing) 2583 Diag(From->getSourceRange().getBegin(), 2584 diag::err_arc_weak_unavailable_assign); 2585 else 2586 Diag(From->getSourceRange().getBegin(), 2587 diag::err_arc_convesion_of_weak_unavailable) 2588 << (Action == AA_Casting) << From->getType() << ToType 2589 << From->getSourceRange(); 2590 } 2591 2592 CastKind Kind = CK_Invalid; 2593 CXXCastPath BasePath; 2594 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2595 return ExprError(); 2596 2597 // Make sure we extend blocks if necessary. 2598 // FIXME: doing this here is really ugly. 2599 if (Kind == CK_BlockPointerToObjCPointerCast) { 2600 ExprResult E = From; 2601 (void) PrepareCastToObjCObjectPointer(E); 2602 From = E.take(); 2603 } 2604 2605 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2606 .take(); 2607 break; 2608 } 2609 2610 case ICK_Pointer_Member: { 2611 CastKind Kind = CK_Invalid; 2612 CXXCastPath BasePath; 2613 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2614 return ExprError(); 2615 if (CheckExceptionSpecCompatibility(From, ToType)) 2616 return ExprError(); 2617 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2618 .take(); 2619 break; 2620 } 2621 2622 case ICK_Boolean_Conversion: 2623 // Perform half-to-boolean conversion via float. 2624 if (From->getType()->isHalfType()) { 2625 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2626 FromType = Context.FloatTy; 2627 } 2628 2629 From = ImpCastExprToType(From, Context.BoolTy, 2630 ScalarTypeToBooleanCastKind(FromType), 2631 VK_RValue, /*BasePath=*/0, CCK).take(); 2632 break; 2633 2634 case ICK_Derived_To_Base: { 2635 CXXCastPath BasePath; 2636 if (CheckDerivedToBaseConversion(From->getType(), 2637 ToType.getNonReferenceType(), 2638 From->getLocStart(), 2639 From->getSourceRange(), 2640 &BasePath, 2641 CStyle)) 2642 return ExprError(); 2643 2644 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2645 CK_DerivedToBase, From->getValueKind(), 2646 &BasePath, CCK).take(); 2647 break; 2648 } 2649 2650 case ICK_Vector_Conversion: 2651 From = ImpCastExprToType(From, ToType, CK_BitCast, 2652 VK_RValue, /*BasePath=*/0, CCK).take(); 2653 break; 2654 2655 case ICK_Vector_Splat: 2656 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2657 VK_RValue, /*BasePath=*/0, CCK).take(); 2658 break; 2659 2660 case ICK_Complex_Real: 2661 // Case 1. x -> _Complex y 2662 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2663 QualType ElType = ToComplex->getElementType(); 2664 bool isFloatingComplex = ElType->isRealFloatingType(); 2665 2666 // x -> y 2667 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2668 // do nothing 2669 } else if (From->getType()->isRealFloatingType()) { 2670 From = ImpCastExprToType(From, ElType, 2671 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2672 } else { 2673 assert(From->getType()->isIntegerType()); 2674 From = ImpCastExprToType(From, ElType, 2675 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2676 } 2677 // y -> _Complex y 2678 From = ImpCastExprToType(From, ToType, 2679 isFloatingComplex ? CK_FloatingRealToComplex 2680 : CK_IntegralRealToComplex).take(); 2681 2682 // Case 2. _Complex x -> y 2683 } else { 2684 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2685 assert(FromComplex); 2686 2687 QualType ElType = FromComplex->getElementType(); 2688 bool isFloatingComplex = ElType->isRealFloatingType(); 2689 2690 // _Complex x -> x 2691 From = ImpCastExprToType(From, ElType, 2692 isFloatingComplex ? CK_FloatingComplexToReal 2693 : CK_IntegralComplexToReal, 2694 VK_RValue, /*BasePath=*/0, CCK).take(); 2695 2696 // x -> y 2697 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2698 // do nothing 2699 } else if (ToType->isRealFloatingType()) { 2700 From = ImpCastExprToType(From, ToType, 2701 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2702 VK_RValue, /*BasePath=*/0, CCK).take(); 2703 } else { 2704 assert(ToType->isIntegerType()); 2705 From = ImpCastExprToType(From, ToType, 2706 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2707 VK_RValue, /*BasePath=*/0, CCK).take(); 2708 } 2709 } 2710 break; 2711 2712 case ICK_Block_Pointer_Conversion: { 2713 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2714 VK_RValue, /*BasePath=*/0, CCK).take(); 2715 break; 2716 } 2717 2718 case ICK_TransparentUnionConversion: { 2719 ExprResult FromRes = Owned(From); 2720 Sema::AssignConvertType ConvTy = 2721 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2722 if (FromRes.isInvalid()) 2723 return ExprError(); 2724 From = FromRes.take(); 2725 assert ((ConvTy == Sema::Compatible) && 2726 "Improper transparent union conversion"); 2727 (void)ConvTy; 2728 break; 2729 } 2730 2731 case ICK_Lvalue_To_Rvalue: 2732 case ICK_Array_To_Pointer: 2733 case ICK_Function_To_Pointer: 2734 case ICK_Qualification: 2735 case ICK_Num_Conversion_Kinds: 2736 llvm_unreachable("Improper second standard conversion"); 2737 } 2738 2739 switch (SCS.Third) { 2740 case ICK_Identity: 2741 // Nothing to do. 2742 break; 2743 2744 case ICK_Qualification: { 2745 // The qualification keeps the category of the inner expression, unless the 2746 // target type isn't a reference. 2747 ExprValueKind VK = ToType->isReferenceType() ? 2748 From->getValueKind() : VK_RValue; 2749 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2750 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2751 2752 if (SCS.DeprecatedStringLiteralToCharPtr && 2753 !getLangOptions().WritableStrings) 2754 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2755 << ToType.getNonReferenceType(); 2756 2757 break; 2758 } 2759 2760 default: 2761 llvm_unreachable("Improper third standard conversion"); 2762 } 2763 2764 return Owned(From); 2765} 2766 2767ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2768 SourceLocation KWLoc, 2769 ParsedType Ty, 2770 SourceLocation RParen) { 2771 TypeSourceInfo *TSInfo; 2772 QualType T = GetTypeFromParser(Ty, &TSInfo); 2773 2774 if (!TSInfo) 2775 TSInfo = Context.getTrivialTypeSourceInfo(T); 2776 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2777} 2778 2779/// \brief Check the completeness of a type in a unary type trait. 2780/// 2781/// If the particular type trait requires a complete type, tries to complete 2782/// it. If completing the type fails, a diagnostic is emitted and false 2783/// returned. If completing the type succeeds or no completion was required, 2784/// returns true. 2785static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2786 UnaryTypeTrait UTT, 2787 SourceLocation Loc, 2788 QualType ArgTy) { 2789 // C++0x [meta.unary.prop]p3: 2790 // For all of the class templates X declared in this Clause, instantiating 2791 // that template with a template argument that is a class template 2792 // specialization may result in the implicit instantiation of the template 2793 // argument if and only if the semantics of X require that the argument 2794 // must be a complete type. 2795 // We apply this rule to all the type trait expressions used to implement 2796 // these class templates. We also try to follow any GCC documented behavior 2797 // in these expressions to ensure portability of standard libraries. 2798 switch (UTT) { 2799 // is_complete_type somewhat obviously cannot require a complete type. 2800 case UTT_IsCompleteType: 2801 // Fall-through 2802 2803 // These traits are modeled on the type predicates in C++0x 2804 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2805 // requiring a complete type, as whether or not they return true cannot be 2806 // impacted by the completeness of the type. 2807 case UTT_IsVoid: 2808 case UTT_IsIntegral: 2809 case UTT_IsFloatingPoint: 2810 case UTT_IsArray: 2811 case UTT_IsPointer: 2812 case UTT_IsLvalueReference: 2813 case UTT_IsRvalueReference: 2814 case UTT_IsMemberFunctionPointer: 2815 case UTT_IsMemberObjectPointer: 2816 case UTT_IsEnum: 2817 case UTT_IsUnion: 2818 case UTT_IsClass: 2819 case UTT_IsFunction: 2820 case UTT_IsReference: 2821 case UTT_IsArithmetic: 2822 case UTT_IsFundamental: 2823 case UTT_IsObject: 2824 case UTT_IsScalar: 2825 case UTT_IsCompound: 2826 case UTT_IsMemberPointer: 2827 // Fall-through 2828 2829 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2830 // which requires some of its traits to have the complete type. However, 2831 // the completeness of the type cannot impact these traits' semantics, and 2832 // so they don't require it. This matches the comments on these traits in 2833 // Table 49. 2834 case UTT_IsConst: 2835 case UTT_IsVolatile: 2836 case UTT_IsSigned: 2837 case UTT_IsUnsigned: 2838 return true; 2839 2840 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2841 // applied to a complete type. 2842 case UTT_IsTrivial: 2843 case UTT_IsTriviallyCopyable: 2844 case UTT_IsStandardLayout: 2845 case UTT_IsPOD: 2846 case UTT_IsLiteral: 2847 case UTT_IsEmpty: 2848 case UTT_IsPolymorphic: 2849 case UTT_IsAbstract: 2850 // Fall-through 2851 2852 // These traits require a complete type. 2853 case UTT_IsFinal: 2854 2855 // These trait expressions are designed to help implement predicates in 2856 // [meta.unary.prop] despite not being named the same. They are specified 2857 // by both GCC and the Embarcadero C++ compiler, and require the complete 2858 // type due to the overarching C++0x type predicates being implemented 2859 // requiring the complete type. 2860 case UTT_HasNothrowAssign: 2861 case UTT_HasNothrowConstructor: 2862 case UTT_HasNothrowCopy: 2863 case UTT_HasTrivialAssign: 2864 case UTT_HasTrivialDefaultConstructor: 2865 case UTT_HasTrivialCopy: 2866 case UTT_HasTrivialDestructor: 2867 case UTT_HasVirtualDestructor: 2868 // Arrays of unknown bound are expressly allowed. 2869 QualType ElTy = ArgTy; 2870 if (ArgTy->isIncompleteArrayType()) 2871 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 2872 2873 // The void type is expressly allowed. 2874 if (ElTy->isVoidType()) 2875 return true; 2876 2877 return !S.RequireCompleteType( 2878 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 2879 } 2880 llvm_unreachable("Type trait not handled by switch"); 2881} 2882 2883static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 2884 SourceLocation KeyLoc, QualType T) { 2885 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 2886 2887 ASTContext &C = Self.Context; 2888 switch(UTT) { 2889 // Type trait expressions corresponding to the primary type category 2890 // predicates in C++0x [meta.unary.cat]. 2891 case UTT_IsVoid: 2892 return T->isVoidType(); 2893 case UTT_IsIntegral: 2894 return T->isIntegralType(C); 2895 case UTT_IsFloatingPoint: 2896 return T->isFloatingType(); 2897 case UTT_IsArray: 2898 return T->isArrayType(); 2899 case UTT_IsPointer: 2900 return T->isPointerType(); 2901 case UTT_IsLvalueReference: 2902 return T->isLValueReferenceType(); 2903 case UTT_IsRvalueReference: 2904 return T->isRValueReferenceType(); 2905 case UTT_IsMemberFunctionPointer: 2906 return T->isMemberFunctionPointerType(); 2907 case UTT_IsMemberObjectPointer: 2908 return T->isMemberDataPointerType(); 2909 case UTT_IsEnum: 2910 return T->isEnumeralType(); 2911 case UTT_IsUnion: 2912 return T->isUnionType(); 2913 case UTT_IsClass: 2914 return T->isClassType() || T->isStructureType(); 2915 case UTT_IsFunction: 2916 return T->isFunctionType(); 2917 2918 // Type trait expressions which correspond to the convenient composition 2919 // predicates in C++0x [meta.unary.comp]. 2920 case UTT_IsReference: 2921 return T->isReferenceType(); 2922 case UTT_IsArithmetic: 2923 return T->isArithmeticType() && !T->isEnumeralType(); 2924 case UTT_IsFundamental: 2925 return T->isFundamentalType(); 2926 case UTT_IsObject: 2927 return T->isObjectType(); 2928 case UTT_IsScalar: 2929 // Note: semantic analysis depends on Objective-C lifetime types to be 2930 // considered scalar types. However, such types do not actually behave 2931 // like scalar types at run time (since they may require retain/release 2932 // operations), so we report them as non-scalar. 2933 if (T->isObjCLifetimeType()) { 2934 switch (T.getObjCLifetime()) { 2935 case Qualifiers::OCL_None: 2936 case Qualifiers::OCL_ExplicitNone: 2937 return true; 2938 2939 case Qualifiers::OCL_Strong: 2940 case Qualifiers::OCL_Weak: 2941 case Qualifiers::OCL_Autoreleasing: 2942 return false; 2943 } 2944 } 2945 2946 return T->isScalarType(); 2947 case UTT_IsCompound: 2948 return T->isCompoundType(); 2949 case UTT_IsMemberPointer: 2950 return T->isMemberPointerType(); 2951 2952 // Type trait expressions which correspond to the type property predicates 2953 // in C++0x [meta.unary.prop]. 2954 case UTT_IsConst: 2955 return T.isConstQualified(); 2956 case UTT_IsVolatile: 2957 return T.isVolatileQualified(); 2958 case UTT_IsTrivial: 2959 return T.isTrivialType(Self.Context); 2960 case UTT_IsTriviallyCopyable: 2961 return T.isTriviallyCopyableType(Self.Context); 2962 case UTT_IsStandardLayout: 2963 return T->isStandardLayoutType(); 2964 case UTT_IsPOD: 2965 return T.isPODType(Self.Context); 2966 case UTT_IsLiteral: 2967 return T->isLiteralType(); 2968 case UTT_IsEmpty: 2969 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2970 return !RD->isUnion() && RD->isEmpty(); 2971 return false; 2972 case UTT_IsPolymorphic: 2973 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2974 return RD->isPolymorphic(); 2975 return false; 2976 case UTT_IsAbstract: 2977 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2978 return RD->isAbstract(); 2979 return false; 2980 case UTT_IsFinal: 2981 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2982 return RD->hasAttr<FinalAttr>(); 2983 return false; 2984 case UTT_IsSigned: 2985 return T->isSignedIntegerType(); 2986 case UTT_IsUnsigned: 2987 return T->isUnsignedIntegerType(); 2988 2989 // Type trait expressions which query classes regarding their construction, 2990 // destruction, and copying. Rather than being based directly on the 2991 // related type predicates in the standard, they are specified by both 2992 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 2993 // specifications. 2994 // 2995 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 2996 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 2997 case UTT_HasTrivialDefaultConstructor: 2998 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 2999 // If __is_pod (type) is true then the trait is true, else if type is 3000 // a cv class or union type (or array thereof) with a trivial default 3001 // constructor ([class.ctor]) then the trait is true, else it is false. 3002 if (T.isPODType(Self.Context)) 3003 return true; 3004 if (const RecordType *RT = 3005 C.getBaseElementType(T)->getAs<RecordType>()) 3006 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDefaultConstructor(); 3007 return false; 3008 case UTT_HasTrivialCopy: 3009 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3010 // If __is_pod (type) is true or type is a reference type then 3011 // the trait is true, else if type is a cv class or union type 3012 // with a trivial copy constructor ([class.copy]) then the trait 3013 // is true, else it is false. 3014 if (T.isPODType(Self.Context) || T->isReferenceType()) 3015 return true; 3016 if (const RecordType *RT = T->getAs<RecordType>()) 3017 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyConstructor(); 3018 return false; 3019 case UTT_HasTrivialAssign: 3020 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3021 // If type is const qualified or is a reference type then the 3022 // trait is false. Otherwise if __is_pod (type) is true then the 3023 // trait is true, else if type is a cv class or union type with 3024 // a trivial copy assignment ([class.copy]) then the trait is 3025 // true, else it is false. 3026 // Note: the const and reference restrictions are interesting, 3027 // given that const and reference members don't prevent a class 3028 // from having a trivial copy assignment operator (but do cause 3029 // errors if the copy assignment operator is actually used, q.v. 3030 // [class.copy]p12). 3031 3032 if (C.getBaseElementType(T).isConstQualified()) 3033 return false; 3034 if (T.isPODType(Self.Context)) 3035 return true; 3036 if (const RecordType *RT = T->getAs<RecordType>()) 3037 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyAssignment(); 3038 return false; 3039 case UTT_HasTrivialDestructor: 3040 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3041 // If __is_pod (type) is true or type is a reference type 3042 // then the trait is true, else if type is a cv class or union 3043 // type (or array thereof) with a trivial destructor 3044 // ([class.dtor]) then the trait is true, else it is 3045 // false. 3046 if (T.isPODType(Self.Context) || T->isReferenceType()) 3047 return true; 3048 3049 // Objective-C++ ARC: autorelease types don't require destruction. 3050 if (T->isObjCLifetimeType() && 3051 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3052 return true; 3053 3054 if (const RecordType *RT = 3055 C.getBaseElementType(T)->getAs<RecordType>()) 3056 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDestructor(); 3057 return false; 3058 // TODO: Propagate nothrowness for implicitly declared special members. 3059 case UTT_HasNothrowAssign: 3060 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3061 // If type is const qualified or is a reference type then the 3062 // trait is false. Otherwise if __has_trivial_assign (type) 3063 // is true then the trait is true, else if type is a cv class 3064 // or union type with copy assignment operators that are known 3065 // not to throw an exception then the trait is true, else it is 3066 // false. 3067 if (C.getBaseElementType(T).isConstQualified()) 3068 return false; 3069 if (T->isReferenceType()) 3070 return false; 3071 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3072 return true; 3073 if (const RecordType *RT = T->getAs<RecordType>()) { 3074 CXXRecordDecl* RD = cast<CXXRecordDecl>(RT->getDecl()); 3075 if (RD->hasTrivialCopyAssignment()) 3076 return true; 3077 3078 bool FoundAssign = false; 3079 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(OO_Equal); 3080 LookupResult Res(Self, DeclarationNameInfo(Name, KeyLoc), 3081 Sema::LookupOrdinaryName); 3082 if (Self.LookupQualifiedName(Res, RD)) { 3083 Res.suppressDiagnostics(); 3084 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3085 Op != OpEnd; ++Op) { 3086 if (isa<FunctionTemplateDecl>(*Op)) 3087 continue; 3088 3089 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3090 if (Operator->isCopyAssignmentOperator()) { 3091 FoundAssign = true; 3092 const FunctionProtoType *CPT 3093 = Operator->getType()->getAs<FunctionProtoType>(); 3094 if (CPT->getExceptionSpecType() == EST_Delayed) 3095 return false; 3096 if (!CPT->isNothrow(Self.Context)) 3097 return false; 3098 } 3099 } 3100 } 3101 3102 return FoundAssign; 3103 } 3104 return false; 3105 case UTT_HasNothrowCopy: 3106 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3107 // If __has_trivial_copy (type) is true then the trait is true, else 3108 // if type is a cv class or union type with copy constructors that are 3109 // known not to throw an exception then the trait is true, else it is 3110 // false. 3111 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3112 return true; 3113 if (const RecordType *RT = T->getAs<RecordType>()) { 3114 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3115 if (RD->hasTrivialCopyConstructor()) 3116 return true; 3117 3118 bool FoundConstructor = false; 3119 unsigned FoundTQs; 3120 DeclContext::lookup_const_iterator Con, ConEnd; 3121 for (llvm::tie(Con, ConEnd) = Self.LookupConstructors(RD); 3122 Con != ConEnd; ++Con) { 3123 // A template constructor is never a copy constructor. 3124 // FIXME: However, it may actually be selected at the actual overload 3125 // resolution point. 3126 if (isa<FunctionTemplateDecl>(*Con)) 3127 continue; 3128 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3129 if (Constructor->isCopyConstructor(FoundTQs)) { 3130 FoundConstructor = true; 3131 const FunctionProtoType *CPT 3132 = Constructor->getType()->getAs<FunctionProtoType>(); 3133 if (CPT->getExceptionSpecType() == EST_Delayed) 3134 return false; 3135 // FIXME: check whether evaluating default arguments can throw. 3136 // For now, we'll be conservative and assume that they can throw. 3137 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3138 return false; 3139 } 3140 } 3141 3142 return FoundConstructor; 3143 } 3144 return false; 3145 case UTT_HasNothrowConstructor: 3146 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3147 // If __has_trivial_constructor (type) is true then the trait is 3148 // true, else if type is a cv class or union type (or array 3149 // thereof) with a default constructor that is known not to 3150 // throw an exception then the trait is true, else it is false. 3151 if (T.isPODType(C) || T->isObjCLifetimeType()) 3152 return true; 3153 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) { 3154 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3155 if (RD->hasTrivialDefaultConstructor()) 3156 return true; 3157 3158 DeclContext::lookup_const_iterator Con, ConEnd; 3159 for (llvm::tie(Con, ConEnd) = Self.LookupConstructors(RD); 3160 Con != ConEnd; ++Con) { 3161 // FIXME: In C++0x, a constructor template can be a default constructor. 3162 if (isa<FunctionTemplateDecl>(*Con)) 3163 continue; 3164 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3165 if (Constructor->isDefaultConstructor()) { 3166 const FunctionProtoType *CPT 3167 = Constructor->getType()->getAs<FunctionProtoType>(); 3168 if (CPT->getExceptionSpecType() == EST_Delayed) 3169 return false; 3170 // TODO: check whether evaluating default arguments can throw. 3171 // For now, we'll be conservative and assume that they can throw. 3172 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3173 } 3174 } 3175 } 3176 return false; 3177 case UTT_HasVirtualDestructor: 3178 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3179 // If type is a class type with a virtual destructor ([class.dtor]) 3180 // then the trait is true, else it is false. 3181 if (const RecordType *Record = T->getAs<RecordType>()) { 3182 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 3183 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3184 return Destructor->isVirtual(); 3185 } 3186 return false; 3187 3188 // These type trait expressions are modeled on the specifications for the 3189 // Embarcadero C++0x type trait functions: 3190 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3191 case UTT_IsCompleteType: 3192 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3193 // Returns True if and only if T is a complete type at the point of the 3194 // function call. 3195 return !T->isIncompleteType(); 3196 } 3197 llvm_unreachable("Type trait not covered by switch"); 3198} 3199 3200ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3201 SourceLocation KWLoc, 3202 TypeSourceInfo *TSInfo, 3203 SourceLocation RParen) { 3204 QualType T = TSInfo->getType(); 3205 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3206 return ExprError(); 3207 3208 bool Value = false; 3209 if (!T->isDependentType()) 3210 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3211 3212 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3213 RParen, Context.BoolTy)); 3214} 3215 3216ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3217 SourceLocation KWLoc, 3218 ParsedType LhsTy, 3219 ParsedType RhsTy, 3220 SourceLocation RParen) { 3221 TypeSourceInfo *LhsTSInfo; 3222 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3223 if (!LhsTSInfo) 3224 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3225 3226 TypeSourceInfo *RhsTSInfo; 3227 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3228 if (!RhsTSInfo) 3229 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3230 3231 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3232} 3233 3234static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc, 3235 ArrayRef<TypeSourceInfo *> Args, 3236 SourceLocation RParenLoc) { 3237 switch (Kind) { 3238 case clang::TT_IsTriviallyConstructible: { 3239 // C++11 [meta.unary.prop]: 3240 // is_trivially_constructible is defined as: 3241 // 3242 // is_constructible<T, Args...>::value is true and the variable 3243 // definition for is_constructible, as defined below, is known to call no 3244 // operation that is not trivial. 3245 // 3246 // The predicate condition for a template specialization 3247 // is_constructible<T, Args...> shall be satisfied if and only if the 3248 // following variable definition would be well-formed for some invented 3249 // variable t: 3250 // 3251 // T t(create<Args>()...); 3252 if (Args.empty()) { 3253 S.Diag(KWLoc, diag::err_type_trait_arity) 3254 << 1 << 1 << 1 << (int)Args.size(); 3255 return false; 3256 } 3257 3258 bool SawVoid = false; 3259 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3260 if (Args[I]->getType()->isVoidType()) { 3261 SawVoid = true; 3262 continue; 3263 } 3264 3265 if (!Args[I]->getType()->isIncompleteType() && 3266 S.RequireCompleteType(KWLoc, Args[I]->getType(), 3267 diag::err_incomplete_type_used_in_type_trait_expr)) 3268 return false; 3269 } 3270 3271 // If any argument was 'void', of course it won't type-check. 3272 if (SawVoid) 3273 return false; 3274 3275 llvm::SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs; 3276 llvm::SmallVector<Expr *, 2> ArgExprs; 3277 ArgExprs.reserve(Args.size() - 1); 3278 for (unsigned I = 1, N = Args.size(); I != N; ++I) { 3279 QualType T = Args[I]->getType(); 3280 if (T->isObjectType() || T->isFunctionType()) 3281 T = S.Context.getRValueReferenceType(T); 3282 OpaqueArgExprs.push_back( 3283 OpaqueValueExpr(Args[I]->getTypeLoc().getSourceRange().getBegin(), 3284 T.getNonLValueExprType(S.Context), 3285 Expr::getValueKindForType(T))); 3286 ArgExprs.push_back(&OpaqueArgExprs.back()); 3287 } 3288 3289 // Perform the initialization in an unevaluated context within a SFINAE 3290 // trap at translation unit scope. 3291 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated); 3292 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true); 3293 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); 3294 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0])); 3295 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc, 3296 RParenLoc)); 3297 InitializationSequence Init(S, To, InitKind, 3298 ArgExprs.begin(), ArgExprs.size()); 3299 if (Init.Failed()) 3300 return false; 3301 3302 ExprResult Result = Init.Perform(S, To, InitKind, 3303 MultiExprArg(ArgExprs.data(), 3304 ArgExprs.size())); 3305 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3306 return false; 3307 3308 // The initialization succeeded; not make sure there are no non-trivial 3309 // calls. 3310 return !Result.get()->hasNonTrivialCall(S.Context); 3311 } 3312 } 3313 3314 return false; 3315} 3316 3317ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3318 ArrayRef<TypeSourceInfo *> Args, 3319 SourceLocation RParenLoc) { 3320 bool Dependent = false; 3321 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3322 if (Args[I]->getType()->isDependentType()) { 3323 Dependent = true; 3324 break; 3325 } 3326 } 3327 3328 bool Value = false; 3329 if (!Dependent) 3330 Value = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc); 3331 3332 return TypeTraitExpr::Create(Context, Context.BoolTy, KWLoc, Kind, 3333 Args, RParenLoc, Value); 3334} 3335 3336ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3337 ArrayRef<ParsedType> Args, 3338 SourceLocation RParenLoc) { 3339 llvm::SmallVector<TypeSourceInfo *, 4> ConvertedArgs; 3340 ConvertedArgs.reserve(Args.size()); 3341 3342 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3343 TypeSourceInfo *TInfo; 3344 QualType T = GetTypeFromParser(Args[I], &TInfo); 3345 if (!TInfo) 3346 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc); 3347 3348 ConvertedArgs.push_back(TInfo); 3349 } 3350 3351 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc); 3352} 3353 3354static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3355 QualType LhsT, QualType RhsT, 3356 SourceLocation KeyLoc) { 3357 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3358 "Cannot evaluate traits of dependent types"); 3359 3360 switch(BTT) { 3361 case BTT_IsBaseOf: { 3362 // C++0x [meta.rel]p2 3363 // Base is a base class of Derived without regard to cv-qualifiers or 3364 // Base and Derived are not unions and name the same class type without 3365 // regard to cv-qualifiers. 3366 3367 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3368 if (!lhsRecord) return false; 3369 3370 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3371 if (!rhsRecord) return false; 3372 3373 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3374 == (lhsRecord == rhsRecord)); 3375 3376 if (lhsRecord == rhsRecord) 3377 return !lhsRecord->getDecl()->isUnion(); 3378 3379 // C++0x [meta.rel]p2: 3380 // If Base and Derived are class types and are different types 3381 // (ignoring possible cv-qualifiers) then Derived shall be a 3382 // complete type. 3383 if (Self.RequireCompleteType(KeyLoc, RhsT, 3384 diag::err_incomplete_type_used_in_type_trait_expr)) 3385 return false; 3386 3387 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3388 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3389 } 3390 case BTT_IsSame: 3391 return Self.Context.hasSameType(LhsT, RhsT); 3392 case BTT_TypeCompatible: 3393 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3394 RhsT.getUnqualifiedType()); 3395 case BTT_IsConvertible: 3396 case BTT_IsConvertibleTo: { 3397 // C++0x [meta.rel]p4: 3398 // Given the following function prototype: 3399 // 3400 // template <class T> 3401 // typename add_rvalue_reference<T>::type create(); 3402 // 3403 // the predicate condition for a template specialization 3404 // is_convertible<From, To> shall be satisfied if and only if 3405 // the return expression in the following code would be 3406 // well-formed, including any implicit conversions to the return 3407 // type of the function: 3408 // 3409 // To test() { 3410 // return create<From>(); 3411 // } 3412 // 3413 // Access checking is performed as if in a context unrelated to To and 3414 // From. Only the validity of the immediate context of the expression 3415 // of the return-statement (including conversions to the return type) 3416 // is considered. 3417 // 3418 // We model the initialization as a copy-initialization of a temporary 3419 // of the appropriate type, which for this expression is identical to the 3420 // return statement (since NRVO doesn't apply). 3421 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3422 LhsT = Self.Context.getRValueReferenceType(LhsT); 3423 3424 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3425 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3426 Expr::getValueKindForType(LhsT)); 3427 Expr *FromPtr = &From; 3428 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3429 SourceLocation())); 3430 3431 // Perform the initialization in an unevaluated context within a SFINAE 3432 // trap at translation unit scope. 3433 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3434 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3435 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3436 InitializationSequence Init(Self, To, Kind, &FromPtr, 1); 3437 if (Init.Failed()) 3438 return false; 3439 3440 ExprResult Result = Init.Perform(Self, To, Kind, MultiExprArg(&FromPtr, 1)); 3441 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3442 } 3443 3444 case BTT_IsTriviallyAssignable: { 3445 // C++11 [meta.unary.prop]p3: 3446 // is_trivially_assignable is defined as: 3447 // is_assignable<T, U>::value is true and the assignment, as defined by 3448 // is_assignable, is known to call no operation that is not trivial 3449 // 3450 // is_assignable is defined as: 3451 // The expression declval<T>() = declval<U>() is well-formed when 3452 // treated as an unevaluated operand (Clause 5). 3453 // 3454 // For both, T and U shall be complete types, (possibly cv-qualified) 3455 // void, or arrays of unknown bound. 3456 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() && 3457 Self.RequireCompleteType(KeyLoc, LhsT, 3458 diag::err_incomplete_type_used_in_type_trait_expr)) 3459 return false; 3460 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() && 3461 Self.RequireCompleteType(KeyLoc, RhsT, 3462 diag::err_incomplete_type_used_in_type_trait_expr)) 3463 return false; 3464 3465 // cv void is never assignable. 3466 if (LhsT->isVoidType() || RhsT->isVoidType()) 3467 return false; 3468 3469 // Build expressions that emulate the effect of declval<T>() and 3470 // declval<U>(). 3471 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3472 LhsT = Self.Context.getRValueReferenceType(LhsT); 3473 if (RhsT->isObjectType() || RhsT->isFunctionType()) 3474 RhsT = Self.Context.getRValueReferenceType(RhsT); 3475 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3476 Expr::getValueKindForType(LhsT)); 3477 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context), 3478 Expr::getValueKindForType(RhsT)); 3479 3480 // Attempt the assignment in an unevaluated context within a SFINAE 3481 // trap at translation unit scope. 3482 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3483 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3484 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3485 ExprResult Result = Self.BuildBinOp(/*S=*/0, KeyLoc, BO_Assign, &Lhs, &Rhs); 3486 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3487 return false; 3488 3489 return !Result.get()->hasNonTrivialCall(Self.Context); 3490 } 3491 } 3492 llvm_unreachable("Unknown type trait or not implemented"); 3493} 3494 3495ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3496 SourceLocation KWLoc, 3497 TypeSourceInfo *LhsTSInfo, 3498 TypeSourceInfo *RhsTSInfo, 3499 SourceLocation RParen) { 3500 QualType LhsT = LhsTSInfo->getType(); 3501 QualType RhsT = RhsTSInfo->getType(); 3502 3503 if (BTT == BTT_TypeCompatible) { 3504 if (getLangOptions().CPlusPlus) { 3505 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3506 << SourceRange(KWLoc, RParen); 3507 return ExprError(); 3508 } 3509 } 3510 3511 bool Value = false; 3512 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3513 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3514 3515 // Select trait result type. 3516 QualType ResultType; 3517 switch (BTT) { 3518 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3519 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3520 case BTT_IsSame: ResultType = Context.BoolTy; break; 3521 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3522 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3523 case BTT_IsTriviallyAssignable: ResultType = Context.BoolTy; 3524 } 3525 3526 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3527 RhsTSInfo, Value, RParen, 3528 ResultType)); 3529} 3530 3531ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3532 SourceLocation KWLoc, 3533 ParsedType Ty, 3534 Expr* DimExpr, 3535 SourceLocation RParen) { 3536 TypeSourceInfo *TSInfo; 3537 QualType T = GetTypeFromParser(Ty, &TSInfo); 3538 if (!TSInfo) 3539 TSInfo = Context.getTrivialTypeSourceInfo(T); 3540 3541 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3542} 3543 3544static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3545 QualType T, Expr *DimExpr, 3546 SourceLocation KeyLoc) { 3547 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3548 3549 switch(ATT) { 3550 case ATT_ArrayRank: 3551 if (T->isArrayType()) { 3552 unsigned Dim = 0; 3553 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3554 ++Dim; 3555 T = AT->getElementType(); 3556 } 3557 return Dim; 3558 } 3559 return 0; 3560 3561 case ATT_ArrayExtent: { 3562 llvm::APSInt Value; 3563 uint64_t Dim; 3564 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3565 Self.PDiag(diag::err_dimension_expr_not_constant_integer), 3566 false).isInvalid()) 3567 return 0; 3568 if (Value.isSigned() && Value.isNegative()) { 3569 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer), 3570 DimExpr->getSourceRange(); 3571 return 0; 3572 } 3573 Dim = Value.getLimitedValue(); 3574 3575 if (T->isArrayType()) { 3576 unsigned D = 0; 3577 bool Matched = false; 3578 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3579 if (Dim == D) { 3580 Matched = true; 3581 break; 3582 } 3583 ++D; 3584 T = AT->getElementType(); 3585 } 3586 3587 if (Matched && T->isArrayType()) { 3588 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3589 return CAT->getSize().getLimitedValue(); 3590 } 3591 } 3592 return 0; 3593 } 3594 } 3595 llvm_unreachable("Unknown type trait or not implemented"); 3596} 3597 3598ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3599 SourceLocation KWLoc, 3600 TypeSourceInfo *TSInfo, 3601 Expr* DimExpr, 3602 SourceLocation RParen) { 3603 QualType T = TSInfo->getType(); 3604 3605 // FIXME: This should likely be tracked as an APInt to remove any host 3606 // assumptions about the width of size_t on the target. 3607 uint64_t Value = 0; 3608 if (!T->isDependentType()) 3609 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3610 3611 // While the specification for these traits from the Embarcadero C++ 3612 // compiler's documentation says the return type is 'unsigned int', Clang 3613 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3614 // compiler, there is no difference. On several other platforms this is an 3615 // important distinction. 3616 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3617 DimExpr, RParen, 3618 Context.getSizeType())); 3619} 3620 3621ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3622 SourceLocation KWLoc, 3623 Expr *Queried, 3624 SourceLocation RParen) { 3625 // If error parsing the expression, ignore. 3626 if (!Queried) 3627 return ExprError(); 3628 3629 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3630 3631 return move(Result); 3632} 3633 3634static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3635 switch (ET) { 3636 case ET_IsLValueExpr: return E->isLValue(); 3637 case ET_IsRValueExpr: return E->isRValue(); 3638 } 3639 llvm_unreachable("Expression trait not covered by switch"); 3640} 3641 3642ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3643 SourceLocation KWLoc, 3644 Expr *Queried, 3645 SourceLocation RParen) { 3646 if (Queried->isTypeDependent()) { 3647 // Delay type-checking for type-dependent expressions. 3648 } else if (Queried->getType()->isPlaceholderType()) { 3649 ExprResult PE = CheckPlaceholderExpr(Queried); 3650 if (PE.isInvalid()) return ExprError(); 3651 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3652 } 3653 3654 bool Value = EvaluateExpressionTrait(ET, Queried); 3655 3656 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3657 RParen, Context.BoolTy)); 3658} 3659 3660QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3661 ExprValueKind &VK, 3662 SourceLocation Loc, 3663 bool isIndirect) { 3664 assert(!LHS.get()->getType()->isPlaceholderType() && 3665 !RHS.get()->getType()->isPlaceholderType() && 3666 "placeholders should have been weeded out by now"); 3667 3668 // The LHS undergoes lvalue conversions if this is ->*. 3669 if (isIndirect) { 3670 LHS = DefaultLvalueConversion(LHS.take()); 3671 if (LHS.isInvalid()) return QualType(); 3672 } 3673 3674 // The RHS always undergoes lvalue conversions. 3675 RHS = DefaultLvalueConversion(RHS.take()); 3676 if (RHS.isInvalid()) return QualType(); 3677 3678 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3679 // C++ 5.5p2 3680 // The binary operator .* [p3: ->*] binds its second operand, which shall 3681 // be of type "pointer to member of T" (where T is a completely-defined 3682 // class type) [...] 3683 QualType RHSType = RHS.get()->getType(); 3684 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3685 if (!MemPtr) { 3686 Diag(Loc, diag::err_bad_memptr_rhs) 3687 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3688 return QualType(); 3689 } 3690 3691 QualType Class(MemPtr->getClass(), 0); 3692 3693 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3694 // member pointer points must be completely-defined. However, there is no 3695 // reason for this semantic distinction, and the rule is not enforced by 3696 // other compilers. Therefore, we do not check this property, as it is 3697 // likely to be considered a defect. 3698 3699 // C++ 5.5p2 3700 // [...] to its first operand, which shall be of class T or of a class of 3701 // which T is an unambiguous and accessible base class. [p3: a pointer to 3702 // such a class] 3703 QualType LHSType = LHS.get()->getType(); 3704 if (isIndirect) { 3705 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3706 LHSType = Ptr->getPointeeType(); 3707 else { 3708 Diag(Loc, diag::err_bad_memptr_lhs) 3709 << OpSpelling << 1 << LHSType 3710 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3711 return QualType(); 3712 } 3713 } 3714 3715 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3716 // If we want to check the hierarchy, we need a complete type. 3717 if (RequireCompleteType(Loc, LHSType, PDiag(diag::err_bad_memptr_lhs) 3718 << OpSpelling << (int)isIndirect)) { 3719 return QualType(); 3720 } 3721 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3722 /*DetectVirtual=*/false); 3723 // FIXME: Would it be useful to print full ambiguity paths, or is that 3724 // overkill? 3725 if (!IsDerivedFrom(LHSType, Class, Paths) || 3726 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3727 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3728 << (int)isIndirect << LHS.get()->getType(); 3729 return QualType(); 3730 } 3731 // Cast LHS to type of use. 3732 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3733 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3734 3735 CXXCastPath BasePath; 3736 BuildBasePathArray(Paths, BasePath); 3737 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3738 &BasePath); 3739 } 3740 3741 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3742 // Diagnose use of pointer-to-member type which when used as 3743 // the functional cast in a pointer-to-member expression. 3744 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3745 return QualType(); 3746 } 3747 3748 // C++ 5.5p2 3749 // The result is an object or a function of the type specified by the 3750 // second operand. 3751 // The cv qualifiers are the union of those in the pointer and the left side, 3752 // in accordance with 5.5p5 and 5.2.5. 3753 QualType Result = MemPtr->getPointeeType(); 3754 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3755 3756 // C++0x [expr.mptr.oper]p6: 3757 // In a .* expression whose object expression is an rvalue, the program is 3758 // ill-formed if the second operand is a pointer to member function with 3759 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3760 // expression is an lvalue, the program is ill-formed if the second operand 3761 // is a pointer to member function with ref-qualifier &&. 3762 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3763 switch (Proto->getRefQualifier()) { 3764 case RQ_None: 3765 // Do nothing 3766 break; 3767 3768 case RQ_LValue: 3769 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3770 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3771 << RHSType << 1 << LHS.get()->getSourceRange(); 3772 break; 3773 3774 case RQ_RValue: 3775 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 3776 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3777 << RHSType << 0 << LHS.get()->getSourceRange(); 3778 break; 3779 } 3780 } 3781 3782 // C++ [expr.mptr.oper]p6: 3783 // The result of a .* expression whose second operand is a pointer 3784 // to a data member is of the same value category as its 3785 // first operand. The result of a .* expression whose second 3786 // operand is a pointer to a member function is a prvalue. The 3787 // result of an ->* expression is an lvalue if its second operand 3788 // is a pointer to data member and a prvalue otherwise. 3789 if (Result->isFunctionType()) { 3790 VK = VK_RValue; 3791 return Context.BoundMemberTy; 3792 } else if (isIndirect) { 3793 VK = VK_LValue; 3794 } else { 3795 VK = LHS.get()->getValueKind(); 3796 } 3797 3798 return Result; 3799} 3800 3801/// \brief Try to convert a type to another according to C++0x 5.16p3. 3802/// 3803/// This is part of the parameter validation for the ? operator. If either 3804/// value operand is a class type, the two operands are attempted to be 3805/// converted to each other. This function does the conversion in one direction. 3806/// It returns true if the program is ill-formed and has already been diagnosed 3807/// as such. 3808static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 3809 SourceLocation QuestionLoc, 3810 bool &HaveConversion, 3811 QualType &ToType) { 3812 HaveConversion = false; 3813 ToType = To->getType(); 3814 3815 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 3816 SourceLocation()); 3817 // C++0x 5.16p3 3818 // The process for determining whether an operand expression E1 of type T1 3819 // can be converted to match an operand expression E2 of type T2 is defined 3820 // as follows: 3821 // -- If E2 is an lvalue: 3822 bool ToIsLvalue = To->isLValue(); 3823 if (ToIsLvalue) { 3824 // E1 can be converted to match E2 if E1 can be implicitly converted to 3825 // type "lvalue reference to T2", subject to the constraint that in the 3826 // conversion the reference must bind directly to E1. 3827 QualType T = Self.Context.getLValueReferenceType(ToType); 3828 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3829 3830 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3831 if (InitSeq.isDirectReferenceBinding()) { 3832 ToType = T; 3833 HaveConversion = true; 3834 return false; 3835 } 3836 3837 if (InitSeq.isAmbiguous()) 3838 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3839 } 3840 3841 // -- If E2 is an rvalue, or if the conversion above cannot be done: 3842 // -- if E1 and E2 have class type, and the underlying class types are 3843 // the same or one is a base class of the other: 3844 QualType FTy = From->getType(); 3845 QualType TTy = To->getType(); 3846 const RecordType *FRec = FTy->getAs<RecordType>(); 3847 const RecordType *TRec = TTy->getAs<RecordType>(); 3848 bool FDerivedFromT = FRec && TRec && FRec != TRec && 3849 Self.IsDerivedFrom(FTy, TTy); 3850 if (FRec && TRec && 3851 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 3852 // E1 can be converted to match E2 if the class of T2 is the 3853 // same type as, or a base class of, the class of T1, and 3854 // [cv2 > cv1]. 3855 if (FRec == TRec || FDerivedFromT) { 3856 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 3857 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3858 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3859 if (InitSeq) { 3860 HaveConversion = true; 3861 return false; 3862 } 3863 3864 if (InitSeq.isAmbiguous()) 3865 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3866 } 3867 } 3868 3869 return false; 3870 } 3871 3872 // -- Otherwise: E1 can be converted to match E2 if E1 can be 3873 // implicitly converted to the type that expression E2 would have 3874 // if E2 were converted to an rvalue (or the type it has, if E2 is 3875 // an rvalue). 3876 // 3877 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 3878 // to the array-to-pointer or function-to-pointer conversions. 3879 if (!TTy->getAs<TagType>()) 3880 TTy = TTy.getUnqualifiedType(); 3881 3882 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3883 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3884 HaveConversion = !InitSeq.Failed(); 3885 ToType = TTy; 3886 if (InitSeq.isAmbiguous()) 3887 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3888 3889 return false; 3890} 3891 3892/// \brief Try to find a common type for two according to C++0x 5.16p5. 3893/// 3894/// This is part of the parameter validation for the ? operator. If either 3895/// value operand is a class type, overload resolution is used to find a 3896/// conversion to a common type. 3897static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 3898 SourceLocation QuestionLoc) { 3899 Expr *Args[2] = { LHS.get(), RHS.get() }; 3900 OverloadCandidateSet CandidateSet(QuestionLoc); 3901 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 2, 3902 CandidateSet); 3903 3904 OverloadCandidateSet::iterator Best; 3905 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 3906 case OR_Success: { 3907 // We found a match. Perform the conversions on the arguments and move on. 3908 ExprResult LHSRes = 3909 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 3910 Best->Conversions[0], Sema::AA_Converting); 3911 if (LHSRes.isInvalid()) 3912 break; 3913 LHS = move(LHSRes); 3914 3915 ExprResult RHSRes = 3916 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 3917 Best->Conversions[1], Sema::AA_Converting); 3918 if (RHSRes.isInvalid()) 3919 break; 3920 RHS = move(RHSRes); 3921 if (Best->Function) 3922 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 3923 return false; 3924 } 3925 3926 case OR_No_Viable_Function: 3927 3928 // Emit a better diagnostic if one of the expressions is a null pointer 3929 // constant and the other is a pointer type. In this case, the user most 3930 // likely forgot to take the address of the other expression. 3931 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 3932 return true; 3933 3934 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3935 << LHS.get()->getType() << RHS.get()->getType() 3936 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3937 return true; 3938 3939 case OR_Ambiguous: 3940 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 3941 << LHS.get()->getType() << RHS.get()->getType() 3942 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3943 // FIXME: Print the possible common types by printing the return types of 3944 // the viable candidates. 3945 break; 3946 3947 case OR_Deleted: 3948 llvm_unreachable("Conditional operator has only built-in overloads"); 3949 } 3950 return true; 3951} 3952 3953/// \brief Perform an "extended" implicit conversion as returned by 3954/// TryClassUnification. 3955static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 3956 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3957 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 3958 SourceLocation()); 3959 Expr *Arg = E.take(); 3960 InitializationSequence InitSeq(Self, Entity, Kind, &Arg, 1); 3961 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, MultiExprArg(&Arg, 1)); 3962 if (Result.isInvalid()) 3963 return true; 3964 3965 E = Result; 3966 return false; 3967} 3968 3969/// \brief Check the operands of ?: under C++ semantics. 3970/// 3971/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 3972/// extension. In this case, LHS == Cond. (But they're not aliases.) 3973QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, ExprResult &RHS, 3974 ExprValueKind &VK, ExprObjectKind &OK, 3975 SourceLocation QuestionLoc) { 3976 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 3977 // interface pointers. 3978 3979 // C++0x 5.16p1 3980 // The first expression is contextually converted to bool. 3981 if (!Cond.get()->isTypeDependent()) { 3982 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 3983 if (CondRes.isInvalid()) 3984 return QualType(); 3985 Cond = move(CondRes); 3986 } 3987 3988 // Assume r-value. 3989 VK = VK_RValue; 3990 OK = OK_Ordinary; 3991 3992 // Either of the arguments dependent? 3993 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 3994 return Context.DependentTy; 3995 3996 // C++0x 5.16p2 3997 // If either the second or the third operand has type (cv) void, ... 3998 QualType LTy = LHS.get()->getType(); 3999 QualType RTy = RHS.get()->getType(); 4000 bool LVoid = LTy->isVoidType(); 4001 bool RVoid = RTy->isVoidType(); 4002 if (LVoid || RVoid) { 4003 // ... then the [l2r] conversions are performed on the second and third 4004 // operands ... 4005 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4006 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4007 if (LHS.isInvalid() || RHS.isInvalid()) 4008 return QualType(); 4009 LTy = LHS.get()->getType(); 4010 RTy = RHS.get()->getType(); 4011 4012 // ... and one of the following shall hold: 4013 // -- The second or the third operand (but not both) is a throw- 4014 // expression; the result is of the type of the other and is an rvalue. 4015 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 4016 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 4017 if (LThrow && !RThrow) 4018 return RTy; 4019 if (RThrow && !LThrow) 4020 return LTy; 4021 4022 // -- Both the second and third operands have type void; the result is of 4023 // type void and is an rvalue. 4024 if (LVoid && RVoid) 4025 return Context.VoidTy; 4026 4027 // Neither holds, error. 4028 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 4029 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 4030 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4031 return QualType(); 4032 } 4033 4034 // Neither is void. 4035 4036 // C++0x 5.16p3 4037 // Otherwise, if the second and third operand have different types, and 4038 // either has (cv) class type, and attempt is made to convert each of those 4039 // operands to the other. 4040 if (!Context.hasSameType(LTy, RTy) && 4041 (LTy->isRecordType() || RTy->isRecordType())) { 4042 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 4043 // These return true if a single direction is already ambiguous. 4044 QualType L2RType, R2LType; 4045 bool HaveL2R, HaveR2L; 4046 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 4047 return QualType(); 4048 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 4049 return QualType(); 4050 4051 // If both can be converted, [...] the program is ill-formed. 4052 if (HaveL2R && HaveR2L) { 4053 Diag(QuestionLoc, diag::err_conditional_ambiguous) 4054 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4055 return QualType(); 4056 } 4057 4058 // If exactly one conversion is possible, that conversion is applied to 4059 // the chosen operand and the converted operands are used in place of the 4060 // original operands for the remainder of this section. 4061 if (HaveL2R) { 4062 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 4063 return QualType(); 4064 LTy = LHS.get()->getType(); 4065 } else if (HaveR2L) { 4066 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 4067 return QualType(); 4068 RTy = RHS.get()->getType(); 4069 } 4070 } 4071 4072 // C++0x 5.16p4 4073 // If the second and third operands are glvalues of the same value 4074 // category and have the same type, the result is of that type and 4075 // value category and it is a bit-field if the second or the third 4076 // operand is a bit-field, or if both are bit-fields. 4077 // We only extend this to bitfields, not to the crazy other kinds of 4078 // l-values. 4079 bool Same = Context.hasSameType(LTy, RTy); 4080 if (Same && 4081 LHS.get()->isGLValue() && 4082 LHS.get()->getValueKind() == RHS.get()->getValueKind() && 4083 LHS.get()->isOrdinaryOrBitFieldObject() && 4084 RHS.get()->isOrdinaryOrBitFieldObject()) { 4085 VK = LHS.get()->getValueKind(); 4086 if (LHS.get()->getObjectKind() == OK_BitField || 4087 RHS.get()->getObjectKind() == OK_BitField) 4088 OK = OK_BitField; 4089 return LTy; 4090 } 4091 4092 // C++0x 5.16p5 4093 // Otherwise, the result is an rvalue. If the second and third operands 4094 // do not have the same type, and either has (cv) class type, ... 4095 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 4096 // ... overload resolution is used to determine the conversions (if any) 4097 // to be applied to the operands. If the overload resolution fails, the 4098 // program is ill-formed. 4099 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 4100 return QualType(); 4101 } 4102 4103 // C++0x 5.16p6 4104 // LValue-to-rvalue, array-to-pointer, and function-to-pointer standard 4105 // conversions are performed on the second and third operands. 4106 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4107 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4108 if (LHS.isInvalid() || RHS.isInvalid()) 4109 return QualType(); 4110 LTy = LHS.get()->getType(); 4111 RTy = RHS.get()->getType(); 4112 4113 // After those conversions, one of the following shall hold: 4114 // -- The second and third operands have the same type; the result 4115 // is of that type. If the operands have class type, the result 4116 // is a prvalue temporary of the result type, which is 4117 // copy-initialized from either the second operand or the third 4118 // operand depending on the value of the first operand. 4119 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 4120 if (LTy->isRecordType()) { 4121 // The operands have class type. Make a temporary copy. 4122 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 4123 ExprResult LHSCopy = PerformCopyInitialization(Entity, 4124 SourceLocation(), 4125 LHS); 4126 if (LHSCopy.isInvalid()) 4127 return QualType(); 4128 4129 ExprResult RHSCopy = PerformCopyInitialization(Entity, 4130 SourceLocation(), 4131 RHS); 4132 if (RHSCopy.isInvalid()) 4133 return QualType(); 4134 4135 LHS = LHSCopy; 4136 RHS = RHSCopy; 4137 } 4138 4139 return LTy; 4140 } 4141 4142 // Extension: conditional operator involving vector types. 4143 if (LTy->isVectorType() || RTy->isVectorType()) 4144 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4145 4146 // -- The second and third operands have arithmetic or enumeration type; 4147 // the usual arithmetic conversions are performed to bring them to a 4148 // common type, and the result is of that type. 4149 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 4150 UsualArithmeticConversions(LHS, RHS); 4151 if (LHS.isInvalid() || RHS.isInvalid()) 4152 return QualType(); 4153 return LHS.get()->getType(); 4154 } 4155 4156 // -- The second and third operands have pointer type, or one has pointer 4157 // type and the other is a null pointer constant; pointer conversions 4158 // and qualification conversions are performed to bring them to their 4159 // composite pointer type. The result is of the composite pointer type. 4160 // -- The second and third operands have pointer to member type, or one has 4161 // pointer to member type and the other is a null pointer constant; 4162 // pointer to member conversions and qualification conversions are 4163 // performed to bring them to a common type, whose cv-qualification 4164 // shall match the cv-qualification of either the second or the third 4165 // operand. The result is of the common type. 4166 bool NonStandardCompositeType = false; 4167 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 4168 isSFINAEContext()? 0 : &NonStandardCompositeType); 4169 if (!Composite.isNull()) { 4170 if (NonStandardCompositeType) 4171 Diag(QuestionLoc, 4172 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 4173 << LTy << RTy << Composite 4174 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4175 4176 return Composite; 4177 } 4178 4179 // Similarly, attempt to find composite type of two objective-c pointers. 4180 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 4181 if (!Composite.isNull()) 4182 return Composite; 4183 4184 // Check if we are using a null with a non-pointer type. 4185 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4186 return QualType(); 4187 4188 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4189 << LHS.get()->getType() << RHS.get()->getType() 4190 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4191 return QualType(); 4192} 4193 4194/// \brief Find a merged pointer type and convert the two expressions to it. 4195/// 4196/// This finds the composite pointer type (or member pointer type) for @p E1 4197/// and @p E2 according to C++0x 5.9p2. It converts both expressions to this 4198/// type and returns it. 4199/// It does not emit diagnostics. 4200/// 4201/// \param Loc The location of the operator requiring these two expressions to 4202/// be converted to the composite pointer type. 4203/// 4204/// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4205/// a non-standard (but still sane) composite type to which both expressions 4206/// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4207/// will be set true. 4208QualType Sema::FindCompositePointerType(SourceLocation Loc, 4209 Expr *&E1, Expr *&E2, 4210 bool *NonStandardCompositeType) { 4211 if (NonStandardCompositeType) 4212 *NonStandardCompositeType = false; 4213 4214 assert(getLangOptions().CPlusPlus && "This function assumes C++"); 4215 QualType T1 = E1->getType(), T2 = E2->getType(); 4216 4217 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4218 !T2->isAnyPointerType() && !T2->isMemberPointerType()) 4219 return QualType(); 4220 4221 // C++0x 5.9p2 4222 // Pointer conversions and qualification conversions are performed on 4223 // pointer operands to bring them to their composite pointer type. If 4224 // one operand is a null pointer constant, the composite pointer type is 4225 // the type of the other operand. 4226 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4227 if (T2->isMemberPointerType()) 4228 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4229 else 4230 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4231 return T2; 4232 } 4233 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4234 if (T1->isMemberPointerType()) 4235 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4236 else 4237 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4238 return T1; 4239 } 4240 4241 // Now both have to be pointers or member pointers. 4242 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4243 (!T2->isPointerType() && !T2->isMemberPointerType())) 4244 return QualType(); 4245 4246 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4247 // the other has type "pointer to cv2 T" and the composite pointer type is 4248 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4249 // Otherwise, the composite pointer type is a pointer type similar to the 4250 // type of one of the operands, with a cv-qualification signature that is 4251 // the union of the cv-qualification signatures of the operand types. 4252 // In practice, the first part here is redundant; it's subsumed by the second. 4253 // What we do here is, we build the two possible composite types, and try the 4254 // conversions in both directions. If only one works, or if the two composite 4255 // types are the same, we have succeeded. 4256 // FIXME: extended qualifiers? 4257 typedef SmallVector<unsigned, 4> QualifierVector; 4258 QualifierVector QualifierUnion; 4259 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4260 ContainingClassVector; 4261 ContainingClassVector MemberOfClass; 4262 QualType Composite1 = Context.getCanonicalType(T1), 4263 Composite2 = Context.getCanonicalType(T2); 4264 unsigned NeedConstBefore = 0; 4265 do { 4266 const PointerType *Ptr1, *Ptr2; 4267 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4268 (Ptr2 = Composite2->getAs<PointerType>())) { 4269 Composite1 = Ptr1->getPointeeType(); 4270 Composite2 = Ptr2->getPointeeType(); 4271 4272 // If we're allowed to create a non-standard composite type, keep track 4273 // of where we need to fill in additional 'const' qualifiers. 4274 if (NonStandardCompositeType && 4275 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4276 NeedConstBefore = QualifierUnion.size(); 4277 4278 QualifierUnion.push_back( 4279 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4280 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4281 continue; 4282 } 4283 4284 const MemberPointerType *MemPtr1, *MemPtr2; 4285 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4286 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4287 Composite1 = MemPtr1->getPointeeType(); 4288 Composite2 = MemPtr2->getPointeeType(); 4289 4290 // If we're allowed to create a non-standard composite type, keep track 4291 // of where we need to fill in additional 'const' qualifiers. 4292 if (NonStandardCompositeType && 4293 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4294 NeedConstBefore = QualifierUnion.size(); 4295 4296 QualifierUnion.push_back( 4297 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4298 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4299 MemPtr2->getClass())); 4300 continue; 4301 } 4302 4303 // FIXME: block pointer types? 4304 4305 // Cannot unwrap any more types. 4306 break; 4307 } while (true); 4308 4309 if (NeedConstBefore && NonStandardCompositeType) { 4310 // Extension: Add 'const' to qualifiers that come before the first qualifier 4311 // mismatch, so that our (non-standard!) composite type meets the 4312 // requirements of C++ [conv.qual]p4 bullet 3. 4313 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4314 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4315 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4316 *NonStandardCompositeType = true; 4317 } 4318 } 4319 } 4320 4321 // Rewrap the composites as pointers or member pointers with the union CVRs. 4322 ContainingClassVector::reverse_iterator MOC 4323 = MemberOfClass.rbegin(); 4324 for (QualifierVector::reverse_iterator 4325 I = QualifierUnion.rbegin(), 4326 E = QualifierUnion.rend(); 4327 I != E; (void)++I, ++MOC) { 4328 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4329 if (MOC->first && MOC->second) { 4330 // Rebuild member pointer type 4331 Composite1 = Context.getMemberPointerType( 4332 Context.getQualifiedType(Composite1, Quals), 4333 MOC->first); 4334 Composite2 = Context.getMemberPointerType( 4335 Context.getQualifiedType(Composite2, Quals), 4336 MOC->second); 4337 } else { 4338 // Rebuild pointer type 4339 Composite1 4340 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4341 Composite2 4342 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4343 } 4344 } 4345 4346 // Try to convert to the first composite pointer type. 4347 InitializedEntity Entity1 4348 = InitializedEntity::InitializeTemporary(Composite1); 4349 InitializationKind Kind 4350 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4351 InitializationSequence E1ToC1(*this, Entity1, Kind, &E1, 1); 4352 InitializationSequence E2ToC1(*this, Entity1, Kind, &E2, 1); 4353 4354 if (E1ToC1 && E2ToC1) { 4355 // Conversion to Composite1 is viable. 4356 if (!Context.hasSameType(Composite1, Composite2)) { 4357 // Composite2 is a different type from Composite1. Check whether 4358 // Composite2 is also viable. 4359 InitializedEntity Entity2 4360 = InitializedEntity::InitializeTemporary(Composite2); 4361 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4362 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4363 if (E1ToC2 && E2ToC2) { 4364 // Both Composite1 and Composite2 are viable and are different; 4365 // this is an ambiguity. 4366 return QualType(); 4367 } 4368 } 4369 4370 // Convert E1 to Composite1 4371 ExprResult E1Result 4372 = E1ToC1.Perform(*this, Entity1, Kind, MultiExprArg(*this,&E1,1)); 4373 if (E1Result.isInvalid()) 4374 return QualType(); 4375 E1 = E1Result.takeAs<Expr>(); 4376 4377 // Convert E2 to Composite1 4378 ExprResult E2Result 4379 = E2ToC1.Perform(*this, Entity1, Kind, MultiExprArg(*this,&E2,1)); 4380 if (E2Result.isInvalid()) 4381 return QualType(); 4382 E2 = E2Result.takeAs<Expr>(); 4383 4384 return Composite1; 4385 } 4386 4387 // Check whether Composite2 is viable. 4388 InitializedEntity Entity2 4389 = InitializedEntity::InitializeTemporary(Composite2); 4390 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4391 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4392 if (!E1ToC2 || !E2ToC2) 4393 return QualType(); 4394 4395 // Convert E1 to Composite2 4396 ExprResult E1Result 4397 = E1ToC2.Perform(*this, Entity2, Kind, MultiExprArg(*this, &E1, 1)); 4398 if (E1Result.isInvalid()) 4399 return QualType(); 4400 E1 = E1Result.takeAs<Expr>(); 4401 4402 // Convert E2 to Composite2 4403 ExprResult E2Result 4404 = E2ToC2.Perform(*this, Entity2, Kind, MultiExprArg(*this, &E2, 1)); 4405 if (E2Result.isInvalid()) 4406 return QualType(); 4407 E2 = E2Result.takeAs<Expr>(); 4408 4409 return Composite2; 4410} 4411 4412ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4413 if (!E) 4414 return ExprError(); 4415 4416 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4417 4418 // If the result is a glvalue, we shouldn't bind it. 4419 if (!E->isRValue()) 4420 return Owned(E); 4421 4422 // In ARC, calls that return a retainable type can return retained, 4423 // in which case we have to insert a consuming cast. 4424 if (getLangOptions().ObjCAutoRefCount && 4425 E->getType()->isObjCRetainableType()) { 4426 4427 bool ReturnsRetained; 4428 4429 // For actual calls, we compute this by examining the type of the 4430 // called value. 4431 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4432 Expr *Callee = Call->getCallee()->IgnoreParens(); 4433 QualType T = Callee->getType(); 4434 4435 if (T == Context.BoundMemberTy) { 4436 // Handle pointer-to-members. 4437 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4438 T = BinOp->getRHS()->getType(); 4439 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4440 T = Mem->getMemberDecl()->getType(); 4441 } 4442 4443 if (const PointerType *Ptr = T->getAs<PointerType>()) 4444 T = Ptr->getPointeeType(); 4445 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4446 T = Ptr->getPointeeType(); 4447 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4448 T = MemPtr->getPointeeType(); 4449 4450 const FunctionType *FTy = T->getAs<FunctionType>(); 4451 assert(FTy && "call to value not of function type?"); 4452 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4453 4454 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4455 // type always produce a +1 object. 4456 } else if (isa<StmtExpr>(E)) { 4457 ReturnsRetained = true; 4458 4459 // For message sends and property references, we try to find an 4460 // actual method. FIXME: we should infer retention by selector in 4461 // cases where we don't have an actual method. 4462 } else { 4463 ObjCMethodDecl *D = 0; 4464 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4465 D = Send->getMethodDecl(); 4466 } 4467 4468 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4469 4470 // Don't do reclaims on performSelector calls; despite their 4471 // return type, the invoked method doesn't necessarily actually 4472 // return an object. 4473 if (!ReturnsRetained && 4474 D && D->getMethodFamily() == OMF_performSelector) 4475 return Owned(E); 4476 } 4477 4478 // Don't reclaim an object of Class type. 4479 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4480 return Owned(E); 4481 4482 ExprNeedsCleanups = true; 4483 4484 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4485 : CK_ARCReclaimReturnedObject); 4486 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4487 VK_RValue)); 4488 } 4489 4490 if (!getLangOptions().CPlusPlus) 4491 return Owned(E); 4492 4493 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4494 // a fast path for the common case that the type is directly a RecordType. 4495 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4496 const RecordType *RT = 0; 4497 while (!RT) { 4498 switch (T->getTypeClass()) { 4499 case Type::Record: 4500 RT = cast<RecordType>(T); 4501 break; 4502 case Type::ConstantArray: 4503 case Type::IncompleteArray: 4504 case Type::VariableArray: 4505 case Type::DependentSizedArray: 4506 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4507 break; 4508 default: 4509 return Owned(E); 4510 } 4511 } 4512 4513 // That should be enough to guarantee that this type is complete, if we're 4514 // not processing a decltype expression. 4515 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4516 if (RD->isInvalidDecl() || RD->isDependentContext()) 4517 return Owned(E); 4518 4519 bool IsDecltype = ExprEvalContexts.back().IsDecltype; 4520 CXXDestructorDecl *Destructor = IsDecltype ? 0 : LookupDestructor(RD); 4521 4522 if (Destructor) { 4523 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4524 CheckDestructorAccess(E->getExprLoc(), Destructor, 4525 PDiag(diag::err_access_dtor_temp) 4526 << E->getType()); 4527 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 4528 4529 // If destructor is trivial, we can avoid the extra copy. 4530 if (Destructor->isTrivial()) 4531 return Owned(E); 4532 4533 // We need a cleanup, but we don't need to remember the temporary. 4534 ExprNeedsCleanups = true; 4535 } 4536 4537 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4538 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E); 4539 4540 if (IsDecltype) 4541 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind); 4542 4543 return Owned(Bind); 4544} 4545 4546ExprResult 4547Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4548 if (SubExpr.isInvalid()) 4549 return ExprError(); 4550 4551 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4552} 4553 4554Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4555 assert(SubExpr && "sub expression can't be null!"); 4556 4557 CleanupVarDeclMarking(); 4558 4559 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4560 assert(ExprCleanupObjects.size() >= FirstCleanup); 4561 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4562 if (!ExprNeedsCleanups) 4563 return SubExpr; 4564 4565 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4566 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4567 ExprCleanupObjects.size() - FirstCleanup); 4568 4569 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4570 DiscardCleanupsInEvaluationContext(); 4571 4572 return E; 4573} 4574 4575Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4576 assert(SubStmt && "sub statement can't be null!"); 4577 4578 CleanupVarDeclMarking(); 4579 4580 if (!ExprNeedsCleanups) 4581 return SubStmt; 4582 4583 // FIXME: In order to attach the temporaries, wrap the statement into 4584 // a StmtExpr; currently this is only used for asm statements. 4585 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4586 // a new AsmStmtWithTemporaries. 4587 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, &SubStmt, 1, 4588 SourceLocation(), 4589 SourceLocation()); 4590 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4591 SourceLocation()); 4592 return MaybeCreateExprWithCleanups(E); 4593} 4594 4595/// Process the expression contained within a decltype. For such expressions, 4596/// certain semantic checks on temporaries are delayed until this point, and 4597/// are omitted for the 'topmost' call in the decltype expression. If the 4598/// topmost call bound a temporary, strip that temporary off the expression. 4599ExprResult Sema::ActOnDecltypeExpression(Expr *E) { 4600 ExpressionEvaluationContextRecord &Rec = ExprEvalContexts.back(); 4601 assert(Rec.IsDecltype && "not in a decltype expression"); 4602 4603 // C++11 [expr.call]p11: 4604 // If a function call is a prvalue of object type, 4605 // -- if the function call is either 4606 // -- the operand of a decltype-specifier, or 4607 // -- the right operand of a comma operator that is the operand of a 4608 // decltype-specifier, 4609 // a temporary object is not introduced for the prvalue. 4610 4611 // Recursively rebuild ParenExprs and comma expressions to strip out the 4612 // outermost CXXBindTemporaryExpr, if any. 4613 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 4614 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr()); 4615 if (SubExpr.isInvalid()) 4616 return ExprError(); 4617 if (SubExpr.get() == PE->getSubExpr()) 4618 return Owned(E); 4619 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.take()); 4620 } 4621 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 4622 if (BO->getOpcode() == BO_Comma) { 4623 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS()); 4624 if (RHS.isInvalid()) 4625 return ExprError(); 4626 if (RHS.get() == BO->getRHS()) 4627 return Owned(E); 4628 return Owned(new (Context) BinaryOperator(BO->getLHS(), RHS.take(), 4629 BO_Comma, BO->getType(), 4630 BO->getValueKind(), 4631 BO->getObjectKind(), 4632 BO->getOperatorLoc())); 4633 } 4634 } 4635 4636 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E); 4637 if (TopBind) 4638 E = TopBind->getSubExpr(); 4639 4640 // Disable the special decltype handling now. 4641 Rec.IsDecltype = false; 4642 4643 // Perform the semantic checks we delayed until this point. 4644 CallExpr *TopCall = dyn_cast<CallExpr>(E); 4645 for (unsigned I = 0, N = Rec.DelayedDecltypeCalls.size(); I != N; ++I) { 4646 CallExpr *Call = Rec.DelayedDecltypeCalls[I]; 4647 if (Call == TopCall) 4648 continue; 4649 4650 if (CheckCallReturnType(Call->getCallReturnType(), 4651 Call->getSourceRange().getBegin(), 4652 Call, Call->getDirectCallee())) 4653 return ExprError(); 4654 } 4655 4656 // Now all relevant types are complete, check the destructors are accessible 4657 // and non-deleted, and annotate them on the temporaries. 4658 for (unsigned I = 0, N = Rec.DelayedDecltypeBinds.size(); I != N; ++I) { 4659 CXXBindTemporaryExpr *Bind = Rec.DelayedDecltypeBinds[I]; 4660 if (Bind == TopBind) 4661 continue; 4662 4663 CXXTemporary *Temp = Bind->getTemporary(); 4664 4665 CXXRecordDecl *RD = 4666 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 4667 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4668 Temp->setDestructor(Destructor); 4669 4670 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4671 CheckDestructorAccess(E->getExprLoc(), Destructor, 4672 PDiag(diag::err_access_dtor_temp) 4673 << E->getType()); 4674 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 4675 4676 // We need a cleanup, but we don't need to remember the temporary. 4677 ExprNeedsCleanups = true; 4678 } 4679 4680 // Possibly strip off the top CXXBindTemporaryExpr. 4681 return Owned(E); 4682} 4683 4684ExprResult 4685Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4686 tok::TokenKind OpKind, ParsedType &ObjectType, 4687 bool &MayBePseudoDestructor) { 4688 // Since this might be a postfix expression, get rid of ParenListExprs. 4689 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4690 if (Result.isInvalid()) return ExprError(); 4691 Base = Result.get(); 4692 4693 Result = CheckPlaceholderExpr(Base); 4694 if (Result.isInvalid()) return ExprError(); 4695 Base = Result.take(); 4696 4697 QualType BaseType = Base->getType(); 4698 MayBePseudoDestructor = false; 4699 if (BaseType->isDependentType()) { 4700 // If we have a pointer to a dependent type and are using the -> operator, 4701 // the object type is the type that the pointer points to. We might still 4702 // have enough information about that type to do something useful. 4703 if (OpKind == tok::arrow) 4704 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 4705 BaseType = Ptr->getPointeeType(); 4706 4707 ObjectType = ParsedType::make(BaseType); 4708 MayBePseudoDestructor = true; 4709 return Owned(Base); 4710 } 4711 4712 // C++ [over.match.oper]p8: 4713 // [...] When operator->returns, the operator-> is applied to the value 4714 // returned, with the original second operand. 4715 if (OpKind == tok::arrow) { 4716 // The set of types we've considered so far. 4717 llvm::SmallPtrSet<CanQualType,8> CTypes; 4718 SmallVector<SourceLocation, 8> Locations; 4719 CTypes.insert(Context.getCanonicalType(BaseType)); 4720 4721 while (BaseType->isRecordType()) { 4722 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 4723 if (Result.isInvalid()) 4724 return ExprError(); 4725 Base = Result.get(); 4726 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 4727 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 4728 BaseType = Base->getType(); 4729 CanQualType CBaseType = Context.getCanonicalType(BaseType); 4730 if (!CTypes.insert(CBaseType)) { 4731 Diag(OpLoc, diag::err_operator_arrow_circular); 4732 for (unsigned i = 0; i < Locations.size(); i++) 4733 Diag(Locations[i], diag::note_declared_at); 4734 return ExprError(); 4735 } 4736 } 4737 4738 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 4739 BaseType = BaseType->getPointeeType(); 4740 } 4741 4742 // Objective-C properties allow "." access on Objective-C pointer types, 4743 // so adjust the base type to the object type itself. 4744 if (BaseType->isObjCObjectPointerType()) 4745 BaseType = BaseType->getPointeeType(); 4746 4747 // C++ [basic.lookup.classref]p2: 4748 // [...] If the type of the object expression is of pointer to scalar 4749 // type, the unqualified-id is looked up in the context of the complete 4750 // postfix-expression. 4751 // 4752 // This also indicates that we could be parsing a pseudo-destructor-name. 4753 // Note that Objective-C class and object types can be pseudo-destructor 4754 // expressions or normal member (ivar or property) access expressions. 4755 if (BaseType->isObjCObjectOrInterfaceType()) { 4756 MayBePseudoDestructor = true; 4757 } else if (!BaseType->isRecordType()) { 4758 ObjectType = ParsedType(); 4759 MayBePseudoDestructor = true; 4760 return Owned(Base); 4761 } 4762 4763 // The object type must be complete (or dependent). 4764 if (!BaseType->isDependentType() && 4765 RequireCompleteType(OpLoc, BaseType, 4766 PDiag(diag::err_incomplete_member_access))) 4767 return ExprError(); 4768 4769 // C++ [basic.lookup.classref]p2: 4770 // If the id-expression in a class member access (5.2.5) is an 4771 // unqualified-id, and the type of the object expression is of a class 4772 // type C (or of pointer to a class type C), the unqualified-id is looked 4773 // up in the scope of class C. [...] 4774 ObjectType = ParsedType::make(BaseType); 4775 return move(Base); 4776} 4777 4778ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 4779 Expr *MemExpr) { 4780 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 4781 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 4782 << isa<CXXPseudoDestructorExpr>(MemExpr) 4783 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 4784 4785 return ActOnCallExpr(/*Scope*/ 0, 4786 MemExpr, 4787 /*LPLoc*/ ExpectedLParenLoc, 4788 MultiExprArg(), 4789 /*RPLoc*/ ExpectedLParenLoc); 4790} 4791 4792static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 4793 tok::TokenKind& OpKind, SourceLocation OpLoc) { 4794 if (Base->hasPlaceholderType()) { 4795 ExprResult result = S.CheckPlaceholderExpr(Base); 4796 if (result.isInvalid()) return true; 4797 Base = result.take(); 4798 } 4799 ObjectType = Base->getType(); 4800 4801 // C++ [expr.pseudo]p2: 4802 // The left-hand side of the dot operator shall be of scalar type. The 4803 // left-hand side of the arrow operator shall be of pointer to scalar type. 4804 // This scalar type is the object type. 4805 // Note that this is rather different from the normal handling for the 4806 // arrow operator. 4807 if (OpKind == tok::arrow) { 4808 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 4809 ObjectType = Ptr->getPointeeType(); 4810 } else if (!Base->isTypeDependent()) { 4811 // The user wrote "p->" when she probably meant "p."; fix it. 4812 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 4813 << ObjectType << true 4814 << FixItHint::CreateReplacement(OpLoc, "."); 4815 if (S.isSFINAEContext()) 4816 return true; 4817 4818 OpKind = tok::period; 4819 } 4820 } 4821 4822 return false; 4823} 4824 4825ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 4826 SourceLocation OpLoc, 4827 tok::TokenKind OpKind, 4828 const CXXScopeSpec &SS, 4829 TypeSourceInfo *ScopeTypeInfo, 4830 SourceLocation CCLoc, 4831 SourceLocation TildeLoc, 4832 PseudoDestructorTypeStorage Destructed, 4833 bool HasTrailingLParen) { 4834 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 4835 4836 QualType ObjectType; 4837 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4838 return ExprError(); 4839 4840 if (!ObjectType->isDependentType() && !ObjectType->isScalarType()) { 4841 if (getLangOptions().MicrosoftMode && ObjectType->isVoidType()) 4842 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 4843 else 4844 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 4845 << ObjectType << Base->getSourceRange(); 4846 return ExprError(); 4847 } 4848 4849 // C++ [expr.pseudo]p2: 4850 // [...] The cv-unqualified versions of the object type and of the type 4851 // designated by the pseudo-destructor-name shall be the same type. 4852 if (DestructedTypeInfo) { 4853 QualType DestructedType = DestructedTypeInfo->getType(); 4854 SourceLocation DestructedTypeStart 4855 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 4856 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 4857 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 4858 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 4859 << ObjectType << DestructedType << Base->getSourceRange() 4860 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 4861 4862 // Recover by setting the destructed type to the object type. 4863 DestructedType = ObjectType; 4864 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 4865 DestructedTypeStart); 4866 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 4867 } else if (DestructedType.getObjCLifetime() != 4868 ObjectType.getObjCLifetime()) { 4869 4870 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 4871 // Okay: just pretend that the user provided the correctly-qualified 4872 // type. 4873 } else { 4874 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 4875 << ObjectType << DestructedType << Base->getSourceRange() 4876 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 4877 } 4878 4879 // Recover by setting the destructed type to the object type. 4880 DestructedType = ObjectType; 4881 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 4882 DestructedTypeStart); 4883 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 4884 } 4885 } 4886 } 4887 4888 // C++ [expr.pseudo]p2: 4889 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 4890 // form 4891 // 4892 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 4893 // 4894 // shall designate the same scalar type. 4895 if (ScopeTypeInfo) { 4896 QualType ScopeType = ScopeTypeInfo->getType(); 4897 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 4898 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 4899 4900 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 4901 diag::err_pseudo_dtor_type_mismatch) 4902 << ObjectType << ScopeType << Base->getSourceRange() 4903 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 4904 4905 ScopeType = QualType(); 4906 ScopeTypeInfo = 0; 4907 } 4908 } 4909 4910 Expr *Result 4911 = new (Context) CXXPseudoDestructorExpr(Context, Base, 4912 OpKind == tok::arrow, OpLoc, 4913 SS.getWithLocInContext(Context), 4914 ScopeTypeInfo, 4915 CCLoc, 4916 TildeLoc, 4917 Destructed); 4918 4919 if (HasTrailingLParen) 4920 return Owned(Result); 4921 4922 return DiagnoseDtorReference(Destructed.getLocation(), Result); 4923} 4924 4925ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 4926 SourceLocation OpLoc, 4927 tok::TokenKind OpKind, 4928 CXXScopeSpec &SS, 4929 UnqualifiedId &FirstTypeName, 4930 SourceLocation CCLoc, 4931 SourceLocation TildeLoc, 4932 UnqualifiedId &SecondTypeName, 4933 bool HasTrailingLParen) { 4934 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4935 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 4936 "Invalid first type name in pseudo-destructor"); 4937 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4938 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 4939 "Invalid second type name in pseudo-destructor"); 4940 4941 QualType ObjectType; 4942 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4943 return ExprError(); 4944 4945 // Compute the object type that we should use for name lookup purposes. Only 4946 // record types and dependent types matter. 4947 ParsedType ObjectTypePtrForLookup; 4948 if (!SS.isSet()) { 4949 if (ObjectType->isRecordType()) 4950 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 4951 else if (ObjectType->isDependentType()) 4952 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 4953 } 4954 4955 // Convert the name of the type being destructed (following the ~) into a 4956 // type (with source-location information). 4957 QualType DestructedType; 4958 TypeSourceInfo *DestructedTypeInfo = 0; 4959 PseudoDestructorTypeStorage Destructed; 4960 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 4961 ParsedType T = getTypeName(*SecondTypeName.Identifier, 4962 SecondTypeName.StartLocation, 4963 S, &SS, true, false, ObjectTypePtrForLookup); 4964 if (!T && 4965 ((SS.isSet() && !computeDeclContext(SS, false)) || 4966 (!SS.isSet() && ObjectType->isDependentType()))) { 4967 // The name of the type being destroyed is a dependent name, and we 4968 // couldn't find anything useful in scope. Just store the identifier and 4969 // it's location, and we'll perform (qualified) name lookup again at 4970 // template instantiation time. 4971 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 4972 SecondTypeName.StartLocation); 4973 } else if (!T) { 4974 Diag(SecondTypeName.StartLocation, 4975 diag::err_pseudo_dtor_destructor_non_type) 4976 << SecondTypeName.Identifier << ObjectType; 4977 if (isSFINAEContext()) 4978 return ExprError(); 4979 4980 // Recover by assuming we had the right type all along. 4981 DestructedType = ObjectType; 4982 } else 4983 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 4984 } else { 4985 // Resolve the template-id to a type. 4986 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 4987 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4988 TemplateId->getTemplateArgs(), 4989 TemplateId->NumArgs); 4990 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 4991 TemplateId->TemplateKWLoc, 4992 TemplateId->Template, 4993 TemplateId->TemplateNameLoc, 4994 TemplateId->LAngleLoc, 4995 TemplateArgsPtr, 4996 TemplateId->RAngleLoc); 4997 if (T.isInvalid() || !T.get()) { 4998 // Recover by assuming we had the right type all along. 4999 DestructedType = ObjectType; 5000 } else 5001 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 5002 } 5003 5004 // If we've performed some kind of recovery, (re-)build the type source 5005 // information. 5006 if (!DestructedType.isNull()) { 5007 if (!DestructedTypeInfo) 5008 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 5009 SecondTypeName.StartLocation); 5010 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5011 } 5012 5013 // Convert the name of the scope type (the type prior to '::') into a type. 5014 TypeSourceInfo *ScopeTypeInfo = 0; 5015 QualType ScopeType; 5016 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5017 FirstTypeName.Identifier) { 5018 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5019 ParsedType T = getTypeName(*FirstTypeName.Identifier, 5020 FirstTypeName.StartLocation, 5021 S, &SS, true, false, ObjectTypePtrForLookup); 5022 if (!T) { 5023 Diag(FirstTypeName.StartLocation, 5024 diag::err_pseudo_dtor_destructor_non_type) 5025 << FirstTypeName.Identifier << ObjectType; 5026 5027 if (isSFINAEContext()) 5028 return ExprError(); 5029 5030 // Just drop this type. It's unnecessary anyway. 5031 ScopeType = QualType(); 5032 } else 5033 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 5034 } else { 5035 // Resolve the template-id to a type. 5036 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 5037 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5038 TemplateId->getTemplateArgs(), 5039 TemplateId->NumArgs); 5040 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5041 TemplateId->TemplateKWLoc, 5042 TemplateId->Template, 5043 TemplateId->TemplateNameLoc, 5044 TemplateId->LAngleLoc, 5045 TemplateArgsPtr, 5046 TemplateId->RAngleLoc); 5047 if (T.isInvalid() || !T.get()) { 5048 // Recover by dropping this type. 5049 ScopeType = QualType(); 5050 } else 5051 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 5052 } 5053 } 5054 5055 if (!ScopeType.isNull() && !ScopeTypeInfo) 5056 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 5057 FirstTypeName.StartLocation); 5058 5059 5060 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 5061 ScopeTypeInfo, CCLoc, TildeLoc, 5062 Destructed, HasTrailingLParen); 5063} 5064 5065ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5066 SourceLocation OpLoc, 5067 tok::TokenKind OpKind, 5068 SourceLocation TildeLoc, 5069 const DeclSpec& DS, 5070 bool HasTrailingLParen) { 5071 QualType ObjectType; 5072 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5073 return ExprError(); 5074 5075 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 5076 5077 TypeLocBuilder TLB; 5078 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 5079 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 5080 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 5081 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 5082 5083 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 5084 0, SourceLocation(), TildeLoc, 5085 Destructed, HasTrailingLParen); 5086} 5087 5088ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 5089 CXXMethodDecl *Method, 5090 bool HadMultipleCandidates) { 5091 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 5092 FoundDecl, Method); 5093 if (Exp.isInvalid()) 5094 return true; 5095 5096 MemberExpr *ME = 5097 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 5098 SourceLocation(), Context.BoundMemberTy, 5099 VK_RValue, OK_Ordinary); 5100 if (HadMultipleCandidates) 5101 ME->setHadMultipleCandidates(true); 5102 5103 QualType ResultType = Method->getResultType(); 5104 ExprValueKind VK = Expr::getValueKindForType(ResultType); 5105 ResultType = ResultType.getNonLValueExprType(Context); 5106 5107 MarkFunctionReferenced(Exp.get()->getLocStart(), Method); 5108 CXXMemberCallExpr *CE = 5109 new (Context) CXXMemberCallExpr(Context, ME, 0, 0, ResultType, VK, 5110 Exp.get()->getLocEnd()); 5111 return CE; 5112} 5113 5114ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 5115 SourceLocation RParen) { 5116 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 5117 Operand->CanThrow(Context), 5118 KeyLoc, RParen)); 5119} 5120 5121ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 5122 Expr *Operand, SourceLocation RParen) { 5123 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 5124} 5125 5126/// Perform the conversions required for an expression used in a 5127/// context that ignores the result. 5128ExprResult Sema::IgnoredValueConversions(Expr *E) { 5129 if (E->hasPlaceholderType()) { 5130 ExprResult result = CheckPlaceholderExpr(E); 5131 if (result.isInvalid()) return Owned(E); 5132 E = result.take(); 5133 } 5134 5135 // C99 6.3.2.1: 5136 // [Except in specific positions,] an lvalue that does not have 5137 // array type is converted to the value stored in the 5138 // designated object (and is no longer an lvalue). 5139 if (E->isRValue()) { 5140 // In C, function designators (i.e. expressions of function type) 5141 // are r-values, but we still want to do function-to-pointer decay 5142 // on them. This is both technically correct and convenient for 5143 // some clients. 5144 if (!getLangOptions().CPlusPlus && E->getType()->isFunctionType()) 5145 return DefaultFunctionArrayConversion(E); 5146 5147 return Owned(E); 5148 } 5149 5150 // Otherwise, this rule does not apply in C++, at least not for the moment. 5151 if (getLangOptions().CPlusPlus) return Owned(E); 5152 5153 // GCC seems to also exclude expressions of incomplete enum type. 5154 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 5155 if (!T->getDecl()->isComplete()) { 5156 // FIXME: stupid workaround for a codegen bug! 5157 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 5158 return Owned(E); 5159 } 5160 } 5161 5162 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 5163 if (Res.isInvalid()) 5164 return Owned(E); 5165 E = Res.take(); 5166 5167 if (!E->getType()->isVoidType()) 5168 RequireCompleteType(E->getExprLoc(), E->getType(), 5169 diag::err_incomplete_type); 5170 return Owned(E); 5171} 5172 5173ExprResult Sema::ActOnFinishFullExpr(Expr *FE) { 5174 ExprResult FullExpr = Owned(FE); 5175 5176 if (!FullExpr.get()) 5177 return ExprError(); 5178 5179 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 5180 return ExprError(); 5181 5182 // Top-level message sends default to 'id' when we're in a debugger. 5183 if (getLangOptions().DebuggerCastResultToId && 5184 FullExpr.get()->getType() == Context.UnknownAnyTy && 5185 isa<ObjCMessageExpr>(FullExpr.get())) { 5186 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 5187 if (FullExpr.isInvalid()) 5188 return ExprError(); 5189 } 5190 5191 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 5192 if (FullExpr.isInvalid()) 5193 return ExprError(); 5194 5195 FullExpr = IgnoredValueConversions(FullExpr.take()); 5196 if (FullExpr.isInvalid()) 5197 return ExprError(); 5198 5199 CheckImplicitConversions(FullExpr.get(), FullExpr.get()->getExprLoc()); 5200 return MaybeCreateExprWithCleanups(FullExpr); 5201} 5202 5203StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 5204 if (!FullStmt) return StmtError(); 5205 5206 return MaybeCreateStmtWithCleanups(FullStmt); 5207} 5208 5209Sema::IfExistsResult 5210Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 5211 CXXScopeSpec &SS, 5212 const DeclarationNameInfo &TargetNameInfo) { 5213 DeclarationName TargetName = TargetNameInfo.getName(); 5214 if (!TargetName) 5215 return IER_DoesNotExist; 5216 5217 // If the name itself is dependent, then the result is dependent. 5218 if (TargetName.isDependentName()) 5219 return IER_Dependent; 5220 5221 // Do the redeclaration lookup in the current scope. 5222 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 5223 Sema::NotForRedeclaration); 5224 LookupParsedName(R, S, &SS); 5225 R.suppressDiagnostics(); 5226 5227 switch (R.getResultKind()) { 5228 case LookupResult::Found: 5229 case LookupResult::FoundOverloaded: 5230 case LookupResult::FoundUnresolvedValue: 5231 case LookupResult::Ambiguous: 5232 return IER_Exists; 5233 5234 case LookupResult::NotFound: 5235 return IER_DoesNotExist; 5236 5237 case LookupResult::NotFoundInCurrentInstantiation: 5238 return IER_Dependent; 5239 } 5240 5241 llvm_unreachable("Invalid LookupResult Kind!"); 5242} 5243 5244Sema::IfExistsResult 5245Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 5246 bool IsIfExists, CXXScopeSpec &SS, 5247 UnqualifiedId &Name) { 5248 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 5249 5250 // Check for unexpanded parameter packs. 5251 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 5252 collectUnexpandedParameterPacks(SS, Unexpanded); 5253 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 5254 if (!Unexpanded.empty()) { 5255 DiagnoseUnexpandedParameterPacks(KeywordLoc, 5256 IsIfExists? UPPC_IfExists 5257 : UPPC_IfNotExists, 5258 Unexpanded); 5259 return IER_Error; 5260 } 5261 5262 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 5263} 5264