SemaExprCXX.cpp revision b9abd87283ac6e929b7e12a577663bc99e61d020
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 (!getLangOpts().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 = LookupDestructor(RD); 645 if (!Destructor) 646 return Owned(E); 647 648 MarkFunctionReferenced(E->getExprLoc(), Destructor); 649 CheckDestructorAccess(E->getExprLoc(), Destructor, 650 PDiag(diag::err_access_dtor_exception) << Ty); 651 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 652 return Owned(E); 653} 654 655QualType Sema::getCurrentThisType() { 656 DeclContext *DC = getFunctionLevelDeclContext(); 657 QualType ThisTy; 658 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) { 659 if (method && method->isInstance()) 660 ThisTy = method->getThisType(Context); 661 } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 662 // C++0x [expr.prim]p4: 663 // Otherwise, if a member-declarator declares a non-static data member 664 // of a class X, the expression this is a prvalue of type "pointer to X" 665 // within the optional brace-or-equal-initializer. 666 Scope *S = getScopeForContext(DC); 667 if (!S || S->getFlags() & Scope::ThisScope) 668 ThisTy = Context.getPointerType(Context.getRecordType(RD)); 669 } 670 671 return ThisTy; 672} 673 674void Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit) { 675 // We don't need to capture this in an unevaluated context. 676 if (ExprEvalContexts.back().Context == Unevaluated && !Explicit) 677 return; 678 679 // Otherwise, check that we can capture 'this'. 680 unsigned NumClosures = 0; 681 for (unsigned idx = FunctionScopes.size() - 1; idx != 0; idx--) { 682 if (CapturingScopeInfo *CSI = 683 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) { 684 if (CSI->CXXThisCaptureIndex != 0) { 685 // 'this' is already being captured; there isn't anything more to do. 686 break; 687 } 688 689 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref || 690 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval || 691 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block || 692 Explicit) { 693 // This closure can capture 'this'; continue looking upwards. 694 NumClosures++; 695 Explicit = false; 696 continue; 697 } 698 // This context can't implicitly capture 'this'; fail out. 699 Diag(Loc, diag::err_this_capture) << Explicit; 700 return; 701 } 702 break; 703 } 704 705 // Mark that we're implicitly capturing 'this' in all the scopes we skipped. 706 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated 707 // contexts. 708 for (unsigned idx = FunctionScopes.size() - 1; 709 NumClosures; --idx, --NumClosures) { 710 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]); 711 Expr *ThisExpr = 0; 712 QualType ThisTy = getCurrentThisType(); 713 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) { 714 // For lambda expressions, build a field and an initializing expression. 715 CXXRecordDecl *Lambda = LSI->Lambda; 716 FieldDecl *Field 717 = FieldDecl::Create(Context, Lambda, Loc, Loc, 0, ThisTy, 718 Context.getTrivialTypeSourceInfo(ThisTy, Loc), 719 0, false, false); 720 Field->setImplicit(true); 721 Field->setAccess(AS_private); 722 Lambda->addDecl(Field); 723 ThisExpr = new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/true); 724 } 725 bool isNested = NumClosures > 1; 726 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr); 727 } 728} 729 730ExprResult Sema::ActOnCXXThis(SourceLocation Loc) { 731 /// C++ 9.3.2: In the body of a non-static member function, the keyword this 732 /// is a non-lvalue expression whose value is the address of the object for 733 /// which the function is called. 734 735 QualType ThisTy = getCurrentThisType(); 736 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use); 737 738 CheckCXXThisCapture(Loc); 739 return Owned(new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false)); 740} 741 742ExprResult 743Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep, 744 SourceLocation LParenLoc, 745 MultiExprArg exprs, 746 SourceLocation RParenLoc) { 747 if (!TypeRep) 748 return ExprError(); 749 750 TypeSourceInfo *TInfo; 751 QualType Ty = GetTypeFromParser(TypeRep, &TInfo); 752 if (!TInfo) 753 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation()); 754 755 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc); 756} 757 758/// ActOnCXXTypeConstructExpr - Parse construction of a specified type. 759/// Can be interpreted either as function-style casting ("int(x)") 760/// or class type construction ("ClassType(x,y,z)") 761/// or creation of a value-initialized type ("int()"). 762ExprResult 763Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo, 764 SourceLocation LParenLoc, 765 MultiExprArg exprs, 766 SourceLocation RParenLoc) { 767 QualType Ty = TInfo->getType(); 768 unsigned NumExprs = exprs.size(); 769 Expr **Exprs = (Expr**)exprs.get(); 770 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc(); 771 772 if (Ty->isDependentType() || 773 CallExpr::hasAnyTypeDependentArguments( 774 llvm::makeArrayRef(Exprs, NumExprs))) { 775 exprs.release(); 776 777 return Owned(CXXUnresolvedConstructExpr::Create(Context, TInfo, 778 LParenLoc, 779 Exprs, NumExprs, 780 RParenLoc)); 781 } 782 783 bool ListInitialization = LParenLoc.isInvalid(); 784 assert((!ListInitialization || (NumExprs == 1 && isa<InitListExpr>(Exprs[0]))) 785 && "List initialization must have initializer list as expression."); 786 SourceRange FullRange = SourceRange(TyBeginLoc, 787 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc); 788 789 // C++ [expr.type.conv]p1: 790 // If the expression list is a single expression, the type conversion 791 // expression is equivalent (in definedness, and if defined in meaning) to the 792 // corresponding cast expression. 793 if (NumExprs == 1 && !ListInitialization) { 794 Expr *Arg = Exprs[0]; 795 exprs.release(); 796 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc); 797 } 798 799 QualType ElemTy = Ty; 800 if (Ty->isArrayType()) { 801 if (!ListInitialization) 802 return ExprError(Diag(TyBeginLoc, 803 diag::err_value_init_for_array_type) << FullRange); 804 ElemTy = Context.getBaseElementType(Ty); 805 } 806 807 if (!Ty->isVoidType() && 808 RequireCompleteType(TyBeginLoc, ElemTy, 809 PDiag(diag::err_invalid_incomplete_type_use) 810 << FullRange)) 811 return ExprError(); 812 813 if (RequireNonAbstractType(TyBeginLoc, Ty, 814 diag::err_allocation_of_abstract_type)) 815 return ExprError(); 816 817 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo); 818 InitializationKind Kind 819 = NumExprs ? ListInitialization 820 ? InitializationKind::CreateDirectList(TyBeginLoc) 821 : InitializationKind::CreateDirect(TyBeginLoc, 822 LParenLoc, RParenLoc) 823 : InitializationKind::CreateValue(TyBeginLoc, 824 LParenLoc, RParenLoc); 825 InitializationSequence InitSeq(*this, Entity, Kind, Exprs, NumExprs); 826 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, move(exprs)); 827 828 if (!Result.isInvalid() && ListInitialization && 829 isa<InitListExpr>(Result.get())) { 830 // If the list-initialization doesn't involve a constructor call, we'll get 831 // the initializer-list (with corrected type) back, but that's not what we 832 // want, since it will be treated as an initializer list in further 833 // processing. Explicitly insert a cast here. 834 InitListExpr *List = cast<InitListExpr>(Result.take()); 835 Result = Owned(CXXFunctionalCastExpr::Create(Context, List->getType(), 836 Expr::getValueKindForType(TInfo->getType()), 837 TInfo, TyBeginLoc, CK_NoOp, 838 List, /*Path=*/0, RParenLoc)); 839 } 840 841 // FIXME: Improve AST representation? 842 return move(Result); 843} 844 845/// doesUsualArrayDeleteWantSize - Answers whether the usual 846/// operator delete[] for the given type has a size_t parameter. 847static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc, 848 QualType allocType) { 849 const RecordType *record = 850 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>(); 851 if (!record) return false; 852 853 // Try to find an operator delete[] in class scope. 854 855 DeclarationName deleteName = 856 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete); 857 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName); 858 S.LookupQualifiedName(ops, record->getDecl()); 859 860 // We're just doing this for information. 861 ops.suppressDiagnostics(); 862 863 // Very likely: there's no operator delete[]. 864 if (ops.empty()) return false; 865 866 // If it's ambiguous, it should be illegal to call operator delete[] 867 // on this thing, so it doesn't matter if we allocate extra space or not. 868 if (ops.isAmbiguous()) return false; 869 870 LookupResult::Filter filter = ops.makeFilter(); 871 while (filter.hasNext()) { 872 NamedDecl *del = filter.next()->getUnderlyingDecl(); 873 874 // C++0x [basic.stc.dynamic.deallocation]p2: 875 // A template instance is never a usual deallocation function, 876 // regardless of its signature. 877 if (isa<FunctionTemplateDecl>(del)) { 878 filter.erase(); 879 continue; 880 } 881 882 // C++0x [basic.stc.dynamic.deallocation]p2: 883 // If class T does not declare [an operator delete[] with one 884 // parameter] but does declare a member deallocation function 885 // named operator delete[] with exactly two parameters, the 886 // second of which has type std::size_t, then this function 887 // is a usual deallocation function. 888 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) { 889 filter.erase(); 890 continue; 891 } 892 } 893 filter.done(); 894 895 if (!ops.isSingleResult()) return false; 896 897 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl()); 898 return (del->getNumParams() == 2); 899} 900 901/// \brief Parsed a C++ 'new' expression (C++ 5.3.4). 902 903/// E.g.: 904/// @code new (memory) int[size][4] @endcode 905/// or 906/// @code ::new Foo(23, "hello") @endcode 907/// 908/// \param StartLoc The first location of the expression. 909/// \param UseGlobal True if 'new' was prefixed with '::'. 910/// \param PlacementLParen Opening paren of the placement arguments. 911/// \param PlacementArgs Placement new arguments. 912/// \param PlacementRParen Closing paren of the placement arguments. 913/// \param TypeIdParens If the type is in parens, the source range. 914/// \param D The type to be allocated, as well as array dimensions. 915/// \param ConstructorLParen Opening paren of the constructor args, empty if 916/// initializer-list syntax is used. 917/// \param ConstructorArgs Constructor/initialization arguments. 918/// \param ConstructorRParen Closing paren of the constructor args. 919ExprResult 920Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal, 921 SourceLocation PlacementLParen, MultiExprArg PlacementArgs, 922 SourceLocation PlacementRParen, SourceRange TypeIdParens, 923 Declarator &D, Expr *Initializer) { 924 bool TypeContainsAuto = D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto; 925 926 Expr *ArraySize = 0; 927 // If the specified type is an array, unwrap it and save the expression. 928 if (D.getNumTypeObjects() > 0 && 929 D.getTypeObject(0).Kind == DeclaratorChunk::Array) { 930 DeclaratorChunk &Chunk = D.getTypeObject(0); 931 if (TypeContainsAuto) 932 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto) 933 << D.getSourceRange()); 934 if (Chunk.Arr.hasStatic) 935 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new) 936 << D.getSourceRange()); 937 if (!Chunk.Arr.NumElts) 938 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size) 939 << D.getSourceRange()); 940 941 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts); 942 D.DropFirstTypeObject(); 943 } 944 945 // Every dimension shall be of constant size. 946 if (ArraySize) { 947 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) { 948 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array) 949 break; 950 951 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr; 952 if (Expr *NumElts = (Expr *)Array.NumElts) { 953 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) { 954 Array.NumElts = VerifyIntegerConstantExpression(NumElts, 0, 955 PDiag(diag::err_new_array_nonconst)).take(); 956 if (!Array.NumElts) 957 return ExprError(); 958 } 959 } 960 } 961 } 962 963 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/0); 964 QualType AllocType = TInfo->getType(); 965 if (D.isInvalidType()) 966 return ExprError(); 967 968 SourceRange DirectInitRange; 969 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) 970 DirectInitRange = List->getSourceRange(); 971 972 return BuildCXXNew(StartLoc, UseGlobal, 973 PlacementLParen, 974 move(PlacementArgs), 975 PlacementRParen, 976 TypeIdParens, 977 AllocType, 978 TInfo, 979 ArraySize, 980 DirectInitRange, 981 Initializer, 982 TypeContainsAuto); 983} 984 985static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style, 986 Expr *Init) { 987 if (!Init) 988 return true; 989 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init)) 990 return PLE->getNumExprs() == 0; 991 if (isa<ImplicitValueInitExpr>(Init)) 992 return true; 993 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) 994 return !CCE->isListInitialization() && 995 CCE->getConstructor()->isDefaultConstructor(); 996 else if (Style == CXXNewExpr::ListInit) { 997 assert(isa<InitListExpr>(Init) && 998 "Shouldn't create list CXXConstructExprs for arrays."); 999 return true; 1000 } 1001 return false; 1002} 1003 1004ExprResult 1005Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal, 1006 SourceLocation PlacementLParen, 1007 MultiExprArg PlacementArgs, 1008 SourceLocation PlacementRParen, 1009 SourceRange TypeIdParens, 1010 QualType AllocType, 1011 TypeSourceInfo *AllocTypeInfo, 1012 Expr *ArraySize, 1013 SourceRange DirectInitRange, 1014 Expr *Initializer, 1015 bool TypeMayContainAuto) { 1016 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange(); 1017 1018 CXXNewExpr::InitializationStyle initStyle; 1019 if (DirectInitRange.isValid()) { 1020 assert(Initializer && "Have parens but no initializer."); 1021 initStyle = CXXNewExpr::CallInit; 1022 } else if (Initializer && isa<InitListExpr>(Initializer)) 1023 initStyle = CXXNewExpr::ListInit; 1024 else { 1025 // In template instantiation, the initializer could be a CXXDefaultArgExpr 1026 // unwrapped from a CXXConstructExpr that was implicitly built. There is no 1027 // particularly sane way we can handle this (especially since it can even 1028 // occur for array new), so we throw the initializer away and have it be 1029 // rebuilt. 1030 if (Initializer && isa<CXXDefaultArgExpr>(Initializer)) 1031 Initializer = 0; 1032 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) || 1033 isa<CXXConstructExpr>(Initializer)) && 1034 "Initializer expression that cannot have been implicitly created."); 1035 initStyle = CXXNewExpr::NoInit; 1036 } 1037 1038 Expr **Inits = &Initializer; 1039 unsigned NumInits = Initializer ? 1 : 0; 1040 if (initStyle == CXXNewExpr::CallInit) { 1041 if (ParenListExpr *List = dyn_cast<ParenListExpr>(Initializer)) { 1042 Inits = List->getExprs(); 1043 NumInits = List->getNumExprs(); 1044 } else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Initializer)){ 1045 if (!isa<CXXTemporaryObjectExpr>(CCE)) { 1046 // Can happen in template instantiation. Since this is just an implicit 1047 // construction, we just take it apart and rebuild it. 1048 Inits = CCE->getArgs(); 1049 NumInits = CCE->getNumArgs(); 1050 } 1051 } 1052 } 1053 1054 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 1055 if (TypeMayContainAuto && AllocType->getContainedAutoType()) { 1056 if (initStyle == CXXNewExpr::NoInit || NumInits == 0) 1057 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg) 1058 << AllocType << TypeRange); 1059 if (initStyle == CXXNewExpr::ListInit) 1060 return ExprError(Diag(Inits[0]->getLocStart(), 1061 diag::err_auto_new_requires_parens) 1062 << AllocType << TypeRange); 1063 if (NumInits > 1) { 1064 Expr *FirstBad = Inits[1]; 1065 return ExprError(Diag(FirstBad->getLocStart(), 1066 diag::err_auto_new_ctor_multiple_expressions) 1067 << AllocType << TypeRange); 1068 } 1069 Expr *Deduce = Inits[0]; 1070 TypeSourceInfo *DeducedType = 0; 1071 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == 1072 DAR_Failed) 1073 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure) 1074 << AllocType << Deduce->getType() 1075 << TypeRange << Deduce->getSourceRange()); 1076 if (!DeducedType) 1077 return ExprError(); 1078 1079 AllocTypeInfo = DeducedType; 1080 AllocType = AllocTypeInfo->getType(); 1081 } 1082 1083 // Per C++0x [expr.new]p5, the type being constructed may be a 1084 // typedef of an array type. 1085 if (!ArraySize) { 1086 if (const ConstantArrayType *Array 1087 = Context.getAsConstantArrayType(AllocType)) { 1088 ArraySize = IntegerLiteral::Create(Context, Array->getSize(), 1089 Context.getSizeType(), 1090 TypeRange.getEnd()); 1091 AllocType = Array->getElementType(); 1092 } 1093 } 1094 1095 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange)) 1096 return ExprError(); 1097 1098 if (initStyle == CXXNewExpr::ListInit && isStdInitializerList(AllocType, 0)) { 1099 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(), 1100 diag::warn_dangling_std_initializer_list) 1101 << /*at end of FE*/0 << Inits[0]->getSourceRange(); 1102 } 1103 1104 // In ARC, infer 'retaining' for the allocated 1105 if (getLangOpts().ObjCAutoRefCount && 1106 AllocType.getObjCLifetime() == Qualifiers::OCL_None && 1107 AllocType->isObjCLifetimeType()) { 1108 AllocType = Context.getLifetimeQualifiedType(AllocType, 1109 AllocType->getObjCARCImplicitLifetime()); 1110 } 1111 1112 QualType ResultType = Context.getPointerType(AllocType); 1113 1114 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have 1115 // integral or enumeration type with a non-negative value." 1116 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped 1117 // enumeration type, or a class type for which a single non-explicit 1118 // conversion function to integral or unscoped enumeration type exists. 1119 if (ArraySize && !ArraySize->isTypeDependent()) { 1120 ExprResult ConvertedSize = ConvertToIntegralOrEnumerationType( 1121 StartLoc, ArraySize, 1122 PDiag(diag::err_array_size_not_integral) << getLangOpts().CPlusPlus0x, 1123 PDiag(diag::err_array_size_incomplete_type) 1124 << ArraySize->getSourceRange(), 1125 PDiag(diag::err_array_size_explicit_conversion), 1126 PDiag(diag::note_array_size_conversion), 1127 PDiag(diag::err_array_size_ambiguous_conversion), 1128 PDiag(diag::note_array_size_conversion), 1129 PDiag(getLangOpts().CPlusPlus0x ? 1130 diag::warn_cxx98_compat_array_size_conversion : 1131 diag::ext_array_size_conversion), 1132 /*AllowScopedEnumerations*/ false); 1133 if (ConvertedSize.isInvalid()) 1134 return ExprError(); 1135 1136 ArraySize = ConvertedSize.take(); 1137 QualType SizeType = ArraySize->getType(); 1138 if (!SizeType->isIntegralOrUnscopedEnumerationType()) 1139 return ExprError(); 1140 1141 // C++98 [expr.new]p7: 1142 // The expression in a direct-new-declarator shall have integral type 1143 // with a non-negative value. 1144 // 1145 // Let's see if this is a constant < 0. If so, we reject it out of 1146 // hand. Otherwise, if it's not a constant, we must have an unparenthesized 1147 // array type. 1148 // 1149 // Note: such a construct has well-defined semantics in C++11: it throws 1150 // std::bad_array_new_length. 1151 if (!ArraySize->isValueDependent()) { 1152 llvm::APSInt Value; 1153 // We've already performed any required implicit conversion to integer or 1154 // unscoped enumeration type. 1155 if (ArraySize->isIntegerConstantExpr(Value, Context)) { 1156 if (Value < llvm::APSInt( 1157 llvm::APInt::getNullValue(Value.getBitWidth()), 1158 Value.isUnsigned())) { 1159 if (getLangOpts().CPlusPlus0x) 1160 Diag(ArraySize->getLocStart(), 1161 diag::warn_typecheck_negative_array_new_size) 1162 << ArraySize->getSourceRange(); 1163 else 1164 return ExprError(Diag(ArraySize->getLocStart(), 1165 diag::err_typecheck_negative_array_size) 1166 << ArraySize->getSourceRange()); 1167 } else if (!AllocType->isDependentType()) { 1168 unsigned ActiveSizeBits = 1169 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value); 1170 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 1171 if (getLangOpts().CPlusPlus0x) 1172 Diag(ArraySize->getLocStart(), 1173 diag::warn_array_new_too_large) 1174 << Value.toString(10) 1175 << ArraySize->getSourceRange(); 1176 else 1177 return ExprError(Diag(ArraySize->getLocStart(), 1178 diag::err_array_too_large) 1179 << Value.toString(10) 1180 << ArraySize->getSourceRange()); 1181 } 1182 } 1183 } else if (TypeIdParens.isValid()) { 1184 // Can't have dynamic array size when the type-id is in parentheses. 1185 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst) 1186 << ArraySize->getSourceRange() 1187 << FixItHint::CreateRemoval(TypeIdParens.getBegin()) 1188 << FixItHint::CreateRemoval(TypeIdParens.getEnd()); 1189 1190 TypeIdParens = SourceRange(); 1191 } 1192 } 1193 1194 // ARC: warn about ABI issues. 1195 if (getLangOpts().ObjCAutoRefCount) { 1196 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1197 if (BaseAllocType.hasStrongOrWeakObjCLifetime()) 1198 Diag(StartLoc, diag::warn_err_new_delete_object_array) 1199 << 0 << BaseAllocType; 1200 } 1201 1202 // Note that we do *not* convert the argument in any way. It can 1203 // be signed, larger than size_t, whatever. 1204 } 1205 1206 FunctionDecl *OperatorNew = 0; 1207 FunctionDecl *OperatorDelete = 0; 1208 Expr **PlaceArgs = (Expr**)PlacementArgs.get(); 1209 unsigned NumPlaceArgs = PlacementArgs.size(); 1210 1211 if (!AllocType->isDependentType() && 1212 !Expr::hasAnyTypeDependentArguments( 1213 llvm::makeArrayRef(PlaceArgs, NumPlaceArgs)) && 1214 FindAllocationFunctions(StartLoc, 1215 SourceRange(PlacementLParen, PlacementRParen), 1216 UseGlobal, AllocType, ArraySize, PlaceArgs, 1217 NumPlaceArgs, OperatorNew, OperatorDelete)) 1218 return ExprError(); 1219 1220 // If this is an array allocation, compute whether the usual array 1221 // deallocation function for the type has a size_t parameter. 1222 bool UsualArrayDeleteWantsSize = false; 1223 if (ArraySize && !AllocType->isDependentType()) 1224 UsualArrayDeleteWantsSize 1225 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType); 1226 1227 SmallVector<Expr *, 8> AllPlaceArgs; 1228 if (OperatorNew) { 1229 // Add default arguments, if any. 1230 const FunctionProtoType *Proto = 1231 OperatorNew->getType()->getAs<FunctionProtoType>(); 1232 VariadicCallType CallType = 1233 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 1234 1235 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, 1236 Proto, 1, PlaceArgs, NumPlaceArgs, 1237 AllPlaceArgs, CallType)) 1238 return ExprError(); 1239 1240 NumPlaceArgs = AllPlaceArgs.size(); 1241 if (NumPlaceArgs > 0) 1242 PlaceArgs = &AllPlaceArgs[0]; 1243 1244 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, 1245 PlaceArgs, NumPlaceArgs); 1246 1247 // FIXME: Missing call to CheckFunctionCall or equivalent 1248 } 1249 1250 // Warn if the type is over-aligned and is being allocated by global operator 1251 // new. 1252 if (NumPlaceArgs == 0 && OperatorNew && 1253 (OperatorNew->isImplicit() || 1254 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) { 1255 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){ 1256 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign(); 1257 if (Align > SuitableAlign) 1258 Diag(StartLoc, diag::warn_overaligned_type) 1259 << AllocType 1260 << unsigned(Align / Context.getCharWidth()) 1261 << unsigned(SuitableAlign / Context.getCharWidth()); 1262 } 1263 } 1264 1265 QualType InitType = AllocType; 1266 // Array 'new' can't have any initializers except empty parentheses. 1267 // Initializer lists are also allowed, in C++11. Rely on the parser for the 1268 // dialect distinction. 1269 if (ResultType->isArrayType() || ArraySize) { 1270 if (!isLegalArrayNewInitializer(initStyle, Initializer)) { 1271 SourceRange InitRange(Inits[0]->getLocStart(), 1272 Inits[NumInits - 1]->getLocEnd()); 1273 Diag(StartLoc, diag::err_new_array_init_args) << InitRange; 1274 return ExprError(); 1275 } 1276 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) { 1277 // We do the initialization typechecking against the array type 1278 // corresponding to the number of initializers + 1 (to also check 1279 // default-initialization). 1280 unsigned NumElements = ILE->getNumInits() + 1; 1281 InitType = Context.getConstantArrayType(AllocType, 1282 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements), 1283 ArrayType::Normal, 0); 1284 } 1285 } 1286 1287 if (!AllocType->isDependentType() && 1288 !Expr::hasAnyTypeDependentArguments( 1289 llvm::makeArrayRef(Inits, NumInits))) { 1290 // C++11 [expr.new]p15: 1291 // A new-expression that creates an object of type T initializes that 1292 // object as follows: 1293 InitializationKind Kind 1294 // - If the new-initializer is omitted, the object is default- 1295 // initialized (8.5); if no initialization is performed, 1296 // the object has indeterminate value 1297 = initStyle == CXXNewExpr::NoInit 1298 ? InitializationKind::CreateDefault(TypeRange.getBegin()) 1299 // - Otherwise, the new-initializer is interpreted according to the 1300 // initialization rules of 8.5 for direct-initialization. 1301 : initStyle == CXXNewExpr::ListInit 1302 ? InitializationKind::CreateDirectList(TypeRange.getBegin()) 1303 : InitializationKind::CreateDirect(TypeRange.getBegin(), 1304 DirectInitRange.getBegin(), 1305 DirectInitRange.getEnd()); 1306 1307 InitializedEntity Entity 1308 = InitializedEntity::InitializeNew(StartLoc, InitType); 1309 InitializationSequence InitSeq(*this, Entity, Kind, Inits, NumInits); 1310 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind, 1311 MultiExprArg(Inits, NumInits)); 1312 if (FullInit.isInvalid()) 1313 return ExprError(); 1314 1315 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because 1316 // we don't want the initialized object to be destructed. 1317 if (CXXBindTemporaryExpr *Binder = 1318 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get())) 1319 FullInit = Owned(Binder->getSubExpr()); 1320 1321 Initializer = FullInit.take(); 1322 } 1323 1324 // Mark the new and delete operators as referenced. 1325 if (OperatorNew) 1326 MarkFunctionReferenced(StartLoc, OperatorNew); 1327 if (OperatorDelete) 1328 MarkFunctionReferenced(StartLoc, OperatorDelete); 1329 1330 // C++0x [expr.new]p17: 1331 // If the new expression creates an array of objects of class type, 1332 // access and ambiguity control are done for the destructor. 1333 QualType BaseAllocType = Context.getBaseElementType(AllocType); 1334 if (ArraySize && !BaseAllocType->isDependentType()) { 1335 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) { 1336 if (CXXDestructorDecl *dtor = LookupDestructor( 1337 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) { 1338 MarkFunctionReferenced(StartLoc, dtor); 1339 CheckDestructorAccess(StartLoc, dtor, 1340 PDiag(diag::err_access_dtor) 1341 << BaseAllocType); 1342 DiagnoseUseOfDecl(dtor, StartLoc); 1343 } 1344 } 1345 } 1346 1347 PlacementArgs.release(); 1348 1349 return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew, 1350 OperatorDelete, 1351 UsualArrayDeleteWantsSize, 1352 PlaceArgs, NumPlaceArgs, TypeIdParens, 1353 ArraySize, initStyle, Initializer, 1354 ResultType, AllocTypeInfo, 1355 StartLoc, DirectInitRange)); 1356} 1357 1358/// \brief Checks that a type is suitable as the allocated type 1359/// in a new-expression. 1360bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, 1361 SourceRange R) { 1362 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an 1363 // abstract class type or array thereof. 1364 if (AllocType->isFunctionType()) 1365 return Diag(Loc, diag::err_bad_new_type) 1366 << AllocType << 0 << R; 1367 else if (AllocType->isReferenceType()) 1368 return Diag(Loc, diag::err_bad_new_type) 1369 << AllocType << 1 << R; 1370 else if (!AllocType->isDependentType() && 1371 RequireCompleteType(Loc, AllocType, 1372 PDiag(diag::err_new_incomplete_type) 1373 << R)) 1374 return true; 1375 else if (RequireNonAbstractType(Loc, AllocType, 1376 diag::err_allocation_of_abstract_type)) 1377 return true; 1378 else if (AllocType->isVariablyModifiedType()) 1379 return Diag(Loc, diag::err_variably_modified_new_type) 1380 << AllocType; 1381 else if (unsigned AddressSpace = AllocType.getAddressSpace()) 1382 return Diag(Loc, diag::err_address_space_qualified_new) 1383 << AllocType.getUnqualifiedType() << AddressSpace; 1384 else if (getLangOpts().ObjCAutoRefCount) { 1385 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) { 1386 QualType BaseAllocType = Context.getBaseElementType(AT); 1387 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None && 1388 BaseAllocType->isObjCLifetimeType()) 1389 return Diag(Loc, diag::err_arc_new_array_without_ownership) 1390 << BaseAllocType; 1391 } 1392 } 1393 1394 return false; 1395} 1396 1397/// \brief Determine whether the given function is a non-placement 1398/// deallocation function. 1399static bool isNonPlacementDeallocationFunction(FunctionDecl *FD) { 1400 if (FD->isInvalidDecl()) 1401 return false; 1402 1403 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 1404 return Method->isUsualDeallocationFunction(); 1405 1406 return ((FD->getOverloadedOperator() == OO_Delete || 1407 FD->getOverloadedOperator() == OO_Array_Delete) && 1408 FD->getNumParams() == 1); 1409} 1410 1411/// FindAllocationFunctions - Finds the overloads of operator new and delete 1412/// that are appropriate for the allocation. 1413bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range, 1414 bool UseGlobal, QualType AllocType, 1415 bool IsArray, Expr **PlaceArgs, 1416 unsigned NumPlaceArgs, 1417 FunctionDecl *&OperatorNew, 1418 FunctionDecl *&OperatorDelete) { 1419 // --- Choosing an allocation function --- 1420 // C++ 5.3.4p8 - 14 & 18 1421 // 1) If UseGlobal is true, only look in the global scope. Else, also look 1422 // in the scope of the allocated class. 1423 // 2) If an array size is given, look for operator new[], else look for 1424 // operator new. 1425 // 3) The first argument is always size_t. Append the arguments from the 1426 // placement form. 1427 1428 SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs); 1429 // We don't care about the actual value of this argument. 1430 // FIXME: Should the Sema create the expression and embed it in the syntax 1431 // tree? Or should the consumer just recalculate the value? 1432 IntegerLiteral Size(Context, llvm::APInt::getNullValue( 1433 Context.getTargetInfo().getPointerWidth(0)), 1434 Context.getSizeType(), 1435 SourceLocation()); 1436 AllocArgs[0] = &Size; 1437 std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1); 1438 1439 // C++ [expr.new]p8: 1440 // If the allocated type is a non-array type, the allocation 1441 // function's name is operator new and the deallocation function's 1442 // name is operator delete. If the allocated type is an array 1443 // type, the allocation function's name is operator new[] and the 1444 // deallocation function's name is operator delete[]. 1445 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName( 1446 IsArray ? OO_Array_New : OO_New); 1447 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 1448 IsArray ? OO_Array_Delete : OO_Delete); 1449 1450 QualType AllocElemType = Context.getBaseElementType(AllocType); 1451 1452 if (AllocElemType->isRecordType() && !UseGlobal) { 1453 CXXRecordDecl *Record 1454 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1455 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1456 AllocArgs.size(), Record, /*AllowMissing=*/true, 1457 OperatorNew)) 1458 return true; 1459 } 1460 if (!OperatorNew) { 1461 // Didn't find a member overload. Look for a global one. 1462 DeclareGlobalNewDelete(); 1463 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1464 if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0], 1465 AllocArgs.size(), TUDecl, /*AllowMissing=*/false, 1466 OperatorNew)) 1467 return true; 1468 } 1469 1470 // We don't need an operator delete if we're running under 1471 // -fno-exceptions. 1472 if (!getLangOpts().Exceptions) { 1473 OperatorDelete = 0; 1474 return false; 1475 } 1476 1477 // FindAllocationOverload can change the passed in arguments, so we need to 1478 // copy them back. 1479 if (NumPlaceArgs > 0) 1480 std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs); 1481 1482 // C++ [expr.new]p19: 1483 // 1484 // If the new-expression begins with a unary :: operator, the 1485 // deallocation function's name is looked up in the global 1486 // scope. Otherwise, if the allocated type is a class type T or an 1487 // array thereof, the deallocation function's name is looked up in 1488 // the scope of T. If this lookup fails to find the name, or if 1489 // the allocated type is not a class type or array thereof, the 1490 // deallocation function's name is looked up in the global scope. 1491 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName); 1492 if (AllocElemType->isRecordType() && !UseGlobal) { 1493 CXXRecordDecl *RD 1494 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl()); 1495 LookupQualifiedName(FoundDelete, RD); 1496 } 1497 if (FoundDelete.isAmbiguous()) 1498 return true; // FIXME: clean up expressions? 1499 1500 if (FoundDelete.empty()) { 1501 DeclareGlobalNewDelete(); 1502 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl()); 1503 } 1504 1505 FoundDelete.suppressDiagnostics(); 1506 1507 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches; 1508 1509 // Whether we're looking for a placement operator delete is dictated 1510 // by whether we selected a placement operator new, not by whether 1511 // we had explicit placement arguments. This matters for things like 1512 // struct A { void *operator new(size_t, int = 0); ... }; 1513 // A *a = new A() 1514 bool isPlacementNew = (NumPlaceArgs > 0 || OperatorNew->param_size() != 1); 1515 1516 if (isPlacementNew) { 1517 // C++ [expr.new]p20: 1518 // A declaration of a placement deallocation function matches the 1519 // declaration of a placement allocation function if it has the 1520 // same number of parameters and, after parameter transformations 1521 // (8.3.5), all parameter types except the first are 1522 // identical. [...] 1523 // 1524 // To perform this comparison, we compute the function type that 1525 // the deallocation function should have, and use that type both 1526 // for template argument deduction and for comparison purposes. 1527 // 1528 // FIXME: this comparison should ignore CC and the like. 1529 QualType ExpectedFunctionType; 1530 { 1531 const FunctionProtoType *Proto 1532 = OperatorNew->getType()->getAs<FunctionProtoType>(); 1533 1534 SmallVector<QualType, 4> ArgTypes; 1535 ArgTypes.push_back(Context.VoidPtrTy); 1536 for (unsigned I = 1, N = Proto->getNumArgs(); I < N; ++I) 1537 ArgTypes.push_back(Proto->getArgType(I)); 1538 1539 FunctionProtoType::ExtProtoInfo EPI; 1540 EPI.Variadic = Proto->isVariadic(); 1541 1542 ExpectedFunctionType 1543 = Context.getFunctionType(Context.VoidTy, ArgTypes.data(), 1544 ArgTypes.size(), EPI); 1545 } 1546 1547 for (LookupResult::iterator D = FoundDelete.begin(), 1548 DEnd = FoundDelete.end(); 1549 D != DEnd; ++D) { 1550 FunctionDecl *Fn = 0; 1551 if (FunctionTemplateDecl *FnTmpl 1552 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) { 1553 // Perform template argument deduction to try to match the 1554 // expected function type. 1555 TemplateDeductionInfo Info(Context, StartLoc); 1556 if (DeduceTemplateArguments(FnTmpl, 0, ExpectedFunctionType, Fn, Info)) 1557 continue; 1558 } else 1559 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl()); 1560 1561 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType)) 1562 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1563 } 1564 } else { 1565 // C++ [expr.new]p20: 1566 // [...] Any non-placement deallocation function matches a 1567 // non-placement allocation function. [...] 1568 for (LookupResult::iterator D = FoundDelete.begin(), 1569 DEnd = FoundDelete.end(); 1570 D != DEnd; ++D) { 1571 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl())) 1572 if (isNonPlacementDeallocationFunction(Fn)) 1573 Matches.push_back(std::make_pair(D.getPair(), Fn)); 1574 } 1575 } 1576 1577 // C++ [expr.new]p20: 1578 // [...] If the lookup finds a single matching deallocation 1579 // function, that function will be called; otherwise, no 1580 // deallocation function will be called. 1581 if (Matches.size() == 1) { 1582 OperatorDelete = Matches[0].second; 1583 1584 // C++0x [expr.new]p20: 1585 // If the lookup finds the two-parameter form of a usual 1586 // deallocation function (3.7.4.2) and that function, considered 1587 // as a placement deallocation function, would have been 1588 // selected as a match for the allocation function, the program 1589 // is ill-formed. 1590 if (NumPlaceArgs && getLangOpts().CPlusPlus0x && 1591 isNonPlacementDeallocationFunction(OperatorDelete)) { 1592 Diag(StartLoc, diag::err_placement_new_non_placement_delete) 1593 << SourceRange(PlaceArgs[0]->getLocStart(), 1594 PlaceArgs[NumPlaceArgs - 1]->getLocEnd()); 1595 Diag(OperatorDelete->getLocation(), diag::note_previous_decl) 1596 << DeleteName; 1597 } else { 1598 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(), 1599 Matches[0].first); 1600 } 1601 } 1602 1603 return false; 1604} 1605 1606/// FindAllocationOverload - Find an fitting overload for the allocation 1607/// function in the specified scope. 1608bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range, 1609 DeclarationName Name, Expr** Args, 1610 unsigned NumArgs, DeclContext *Ctx, 1611 bool AllowMissing, FunctionDecl *&Operator, 1612 bool Diagnose) { 1613 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName); 1614 LookupQualifiedName(R, Ctx); 1615 if (R.empty()) { 1616 if (AllowMissing || !Diagnose) 1617 return false; 1618 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1619 << Name << Range; 1620 } 1621 1622 if (R.isAmbiguous()) 1623 return true; 1624 1625 R.suppressDiagnostics(); 1626 1627 OverloadCandidateSet Candidates(StartLoc); 1628 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end(); 1629 Alloc != AllocEnd; ++Alloc) { 1630 // Even member operator new/delete are implicitly treated as 1631 // static, so don't use AddMemberCandidate. 1632 NamedDecl *D = (*Alloc)->getUnderlyingDecl(); 1633 1634 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) { 1635 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(), 1636 /*ExplicitTemplateArgs=*/0, 1637 llvm::makeArrayRef(Args, NumArgs), 1638 Candidates, 1639 /*SuppressUserConversions=*/false); 1640 continue; 1641 } 1642 1643 FunctionDecl *Fn = cast<FunctionDecl>(D); 1644 AddOverloadCandidate(Fn, Alloc.getPair(), 1645 llvm::makeArrayRef(Args, NumArgs), Candidates, 1646 /*SuppressUserConversions=*/false); 1647 } 1648 1649 // Do the resolution. 1650 OverloadCandidateSet::iterator Best; 1651 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) { 1652 case OR_Success: { 1653 // Got one! 1654 FunctionDecl *FnDecl = Best->Function; 1655 MarkFunctionReferenced(StartLoc, FnDecl); 1656 // The first argument is size_t, and the first parameter must be size_t, 1657 // too. This is checked on declaration and can be assumed. (It can't be 1658 // asserted on, though, since invalid decls are left in there.) 1659 // Watch out for variadic allocator function. 1660 unsigned NumArgsInFnDecl = FnDecl->getNumParams(); 1661 for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) { 1662 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, 1663 FnDecl->getParamDecl(i)); 1664 1665 if (!Diagnose && !CanPerformCopyInitialization(Entity, Owned(Args[i]))) 1666 return true; 1667 1668 ExprResult Result 1669 = PerformCopyInitialization(Entity, SourceLocation(), Owned(Args[i])); 1670 if (Result.isInvalid()) 1671 return true; 1672 1673 Args[i] = Result.takeAs<Expr>(); 1674 } 1675 1676 Operator = FnDecl; 1677 1678 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(), 1679 Best->FoundDecl, Diagnose) == AR_inaccessible) 1680 return true; 1681 1682 return false; 1683 } 1684 1685 case OR_No_Viable_Function: 1686 if (Diagnose) { 1687 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call) 1688 << Name << Range; 1689 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1690 llvm::makeArrayRef(Args, NumArgs)); 1691 } 1692 return true; 1693 1694 case OR_Ambiguous: 1695 if (Diagnose) { 1696 Diag(StartLoc, diag::err_ovl_ambiguous_call) 1697 << Name << Range; 1698 Candidates.NoteCandidates(*this, OCD_ViableCandidates, 1699 llvm::makeArrayRef(Args, NumArgs)); 1700 } 1701 return true; 1702 1703 case OR_Deleted: { 1704 if (Diagnose) { 1705 Diag(StartLoc, diag::err_ovl_deleted_call) 1706 << Best->Function->isDeleted() 1707 << Name 1708 << getDeletedOrUnavailableSuffix(Best->Function) 1709 << Range; 1710 Candidates.NoteCandidates(*this, OCD_AllCandidates, 1711 llvm::makeArrayRef(Args, NumArgs)); 1712 } 1713 return true; 1714 } 1715 } 1716 llvm_unreachable("Unreachable, bad result from BestViableFunction"); 1717} 1718 1719 1720/// DeclareGlobalNewDelete - Declare the global forms of operator new and 1721/// delete. These are: 1722/// @code 1723/// // C++03: 1724/// void* operator new(std::size_t) throw(std::bad_alloc); 1725/// void* operator new[](std::size_t) throw(std::bad_alloc); 1726/// void operator delete(void *) throw(); 1727/// void operator delete[](void *) throw(); 1728/// // C++0x: 1729/// void* operator new(std::size_t); 1730/// void* operator new[](std::size_t); 1731/// void operator delete(void *); 1732/// void operator delete[](void *); 1733/// @endcode 1734/// C++0x operator delete is implicitly noexcept. 1735/// Note that the placement and nothrow forms of new are *not* implicitly 1736/// declared. Their use requires including \<new\>. 1737void Sema::DeclareGlobalNewDelete() { 1738 if (GlobalNewDeleteDeclared) 1739 return; 1740 1741 // C++ [basic.std.dynamic]p2: 1742 // [...] The following allocation and deallocation functions (18.4) are 1743 // implicitly declared in global scope in each translation unit of a 1744 // program 1745 // 1746 // C++03: 1747 // void* operator new(std::size_t) throw(std::bad_alloc); 1748 // void* operator new[](std::size_t) throw(std::bad_alloc); 1749 // void operator delete(void*) throw(); 1750 // void operator delete[](void*) throw(); 1751 // C++0x: 1752 // void* operator new(std::size_t); 1753 // void* operator new[](std::size_t); 1754 // void operator delete(void*); 1755 // void operator delete[](void*); 1756 // 1757 // These implicit declarations introduce only the function names operator 1758 // new, operator new[], operator delete, operator delete[]. 1759 // 1760 // Here, we need to refer to std::bad_alloc, so we will implicitly declare 1761 // "std" or "bad_alloc" as necessary to form the exception specification. 1762 // However, we do not make these implicit declarations visible to name 1763 // lookup. 1764 // Note that the C++0x versions of operator delete are deallocation functions, 1765 // and thus are implicitly noexcept. 1766 if (!StdBadAlloc && !getLangOpts().CPlusPlus0x) { 1767 // The "std::bad_alloc" class has not yet been declared, so build it 1768 // implicitly. 1769 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class, 1770 getOrCreateStdNamespace(), 1771 SourceLocation(), SourceLocation(), 1772 &PP.getIdentifierTable().get("bad_alloc"), 1773 0); 1774 getStdBadAlloc()->setImplicit(true); 1775 } 1776 1777 GlobalNewDeleteDeclared = true; 1778 1779 QualType VoidPtr = Context.getPointerType(Context.VoidTy); 1780 QualType SizeT = Context.getSizeType(); 1781 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew; 1782 1783 DeclareGlobalAllocationFunction( 1784 Context.DeclarationNames.getCXXOperatorName(OO_New), 1785 VoidPtr, SizeT, AssumeSaneOperatorNew); 1786 DeclareGlobalAllocationFunction( 1787 Context.DeclarationNames.getCXXOperatorName(OO_Array_New), 1788 VoidPtr, SizeT, AssumeSaneOperatorNew); 1789 DeclareGlobalAllocationFunction( 1790 Context.DeclarationNames.getCXXOperatorName(OO_Delete), 1791 Context.VoidTy, VoidPtr); 1792 DeclareGlobalAllocationFunction( 1793 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete), 1794 Context.VoidTy, VoidPtr); 1795} 1796 1797/// DeclareGlobalAllocationFunction - Declares a single implicit global 1798/// allocation function if it doesn't already exist. 1799void Sema::DeclareGlobalAllocationFunction(DeclarationName Name, 1800 QualType Return, QualType Argument, 1801 bool AddMallocAttr) { 1802 DeclContext *GlobalCtx = Context.getTranslationUnitDecl(); 1803 1804 // Check if this function is already declared. 1805 { 1806 DeclContext::lookup_iterator Alloc, AllocEnd; 1807 for (llvm::tie(Alloc, AllocEnd) = GlobalCtx->lookup(Name); 1808 Alloc != AllocEnd; ++Alloc) { 1809 // Only look at non-template functions, as it is the predefined, 1810 // non-templated allocation function we are trying to declare here. 1811 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) { 1812 QualType InitialParamType = 1813 Context.getCanonicalType( 1814 Func->getParamDecl(0)->getType().getUnqualifiedType()); 1815 // FIXME: Do we need to check for default arguments here? 1816 if (Func->getNumParams() == 1 && InitialParamType == Argument) { 1817 if(AddMallocAttr && !Func->hasAttr<MallocAttr>()) 1818 Func->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1819 return; 1820 } 1821 } 1822 } 1823 } 1824 1825 QualType BadAllocType; 1826 bool HasBadAllocExceptionSpec 1827 = (Name.getCXXOverloadedOperator() == OO_New || 1828 Name.getCXXOverloadedOperator() == OO_Array_New); 1829 if (HasBadAllocExceptionSpec && !getLangOpts().CPlusPlus0x) { 1830 assert(StdBadAlloc && "Must have std::bad_alloc declared"); 1831 BadAllocType = Context.getTypeDeclType(getStdBadAlloc()); 1832 } 1833 1834 FunctionProtoType::ExtProtoInfo EPI; 1835 if (HasBadAllocExceptionSpec) { 1836 if (!getLangOpts().CPlusPlus0x) { 1837 EPI.ExceptionSpecType = EST_Dynamic; 1838 EPI.NumExceptions = 1; 1839 EPI.Exceptions = &BadAllocType; 1840 } 1841 } else { 1842 EPI.ExceptionSpecType = getLangOpts().CPlusPlus0x ? 1843 EST_BasicNoexcept : EST_DynamicNone; 1844 } 1845 1846 QualType FnType = Context.getFunctionType(Return, &Argument, 1, EPI); 1847 FunctionDecl *Alloc = 1848 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), 1849 SourceLocation(), Name, 1850 FnType, /*TInfo=*/0, SC_None, 1851 SC_None, false, true); 1852 Alloc->setImplicit(); 1853 1854 if (AddMallocAttr) 1855 Alloc->addAttr(::new (Context) MallocAttr(SourceLocation(), Context)); 1856 1857 ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(), 1858 SourceLocation(), 0, 1859 Argument, /*TInfo=*/0, 1860 SC_None, SC_None, 0); 1861 Alloc->setParams(Param); 1862 1863 // FIXME: Also add this declaration to the IdentifierResolver, but 1864 // make sure it is at the end of the chain to coincide with the 1865 // global scope. 1866 Context.getTranslationUnitDecl()->addDecl(Alloc); 1867} 1868 1869bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD, 1870 DeclarationName Name, 1871 FunctionDecl* &Operator, bool Diagnose) { 1872 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName); 1873 // Try to find operator delete/operator delete[] in class scope. 1874 LookupQualifiedName(Found, RD); 1875 1876 if (Found.isAmbiguous()) 1877 return true; 1878 1879 Found.suppressDiagnostics(); 1880 1881 SmallVector<DeclAccessPair,4> Matches; 1882 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1883 F != FEnd; ++F) { 1884 NamedDecl *ND = (*F)->getUnderlyingDecl(); 1885 1886 // Ignore template operator delete members from the check for a usual 1887 // deallocation function. 1888 if (isa<FunctionTemplateDecl>(ND)) 1889 continue; 1890 1891 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction()) 1892 Matches.push_back(F.getPair()); 1893 } 1894 1895 // There's exactly one suitable operator; pick it. 1896 if (Matches.size() == 1) { 1897 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl()); 1898 1899 if (Operator->isDeleted()) { 1900 if (Diagnose) { 1901 Diag(StartLoc, diag::err_deleted_function_use); 1902 NoteDeletedFunction(Operator); 1903 } 1904 return true; 1905 } 1906 1907 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(), 1908 Matches[0], Diagnose) == AR_inaccessible) 1909 return true; 1910 1911 return false; 1912 1913 // We found multiple suitable operators; complain about the ambiguity. 1914 } else if (!Matches.empty()) { 1915 if (Diagnose) { 1916 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found) 1917 << Name << RD; 1918 1919 for (SmallVectorImpl<DeclAccessPair>::iterator 1920 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F) 1921 Diag((*F)->getUnderlyingDecl()->getLocation(), 1922 diag::note_member_declared_here) << Name; 1923 } 1924 return true; 1925 } 1926 1927 // We did find operator delete/operator delete[] declarations, but 1928 // none of them were suitable. 1929 if (!Found.empty()) { 1930 if (Diagnose) { 1931 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found) 1932 << Name << RD; 1933 1934 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end(); 1935 F != FEnd; ++F) 1936 Diag((*F)->getUnderlyingDecl()->getLocation(), 1937 diag::note_member_declared_here) << Name; 1938 } 1939 return true; 1940 } 1941 1942 // Look for a global declaration. 1943 DeclareGlobalNewDelete(); 1944 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 1945 1946 CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation()); 1947 Expr* DeallocArgs[1]; 1948 DeallocArgs[0] = &Null; 1949 if (FindAllocationOverload(StartLoc, SourceRange(), Name, 1950 DeallocArgs, 1, TUDecl, !Diagnose, 1951 Operator, Diagnose)) 1952 return true; 1953 1954 assert(Operator && "Did not find a deallocation function!"); 1955 return false; 1956} 1957 1958/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in: 1959/// @code ::delete ptr; @endcode 1960/// or 1961/// @code delete [] ptr; @endcode 1962ExprResult 1963Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal, 1964 bool ArrayForm, Expr *ExE) { 1965 // C++ [expr.delete]p1: 1966 // The operand shall have a pointer type, or a class type having a single 1967 // conversion function to a pointer type. The result has type void. 1968 // 1969 // DR599 amends "pointer type" to "pointer to object type" in both cases. 1970 1971 ExprResult Ex = Owned(ExE); 1972 FunctionDecl *OperatorDelete = 0; 1973 bool ArrayFormAsWritten = ArrayForm; 1974 bool UsualArrayDeleteWantsSize = false; 1975 1976 if (!Ex.get()->isTypeDependent()) { 1977 // Perform lvalue-to-rvalue cast, if needed. 1978 Ex = DefaultLvalueConversion(Ex.take()); 1979 1980 QualType Type = Ex.get()->getType(); 1981 1982 if (const RecordType *Record = Type->getAs<RecordType>()) { 1983 if (RequireCompleteType(StartLoc, Type, 1984 PDiag(diag::err_delete_incomplete_class_type))) 1985 return ExprError(); 1986 1987 SmallVector<CXXConversionDecl*, 4> ObjectPtrConversions; 1988 1989 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 1990 const UnresolvedSetImpl *Conversions = RD->getVisibleConversionFunctions(); 1991 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 1992 E = Conversions->end(); I != E; ++I) { 1993 NamedDecl *D = I.getDecl(); 1994 if (isa<UsingShadowDecl>(D)) 1995 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1996 1997 // Skip over templated conversion functions; they aren't considered. 1998 if (isa<FunctionTemplateDecl>(D)) 1999 continue; 2000 2001 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 2002 2003 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 2004 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 2005 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType()) 2006 ObjectPtrConversions.push_back(Conv); 2007 } 2008 if (ObjectPtrConversions.size() == 1) { 2009 // We have a single conversion to a pointer-to-object type. Perform 2010 // that conversion. 2011 // TODO: don't redo the conversion calculation. 2012 ExprResult Res = 2013 PerformImplicitConversion(Ex.get(), 2014 ObjectPtrConversions.front()->getConversionType(), 2015 AA_Converting); 2016 if (Res.isUsable()) { 2017 Ex = move(Res); 2018 Type = Ex.get()->getType(); 2019 } 2020 } 2021 else if (ObjectPtrConversions.size() > 1) { 2022 Diag(StartLoc, diag::err_ambiguous_delete_operand) 2023 << Type << Ex.get()->getSourceRange(); 2024 for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) 2025 NoteOverloadCandidate(ObjectPtrConversions[i]); 2026 return ExprError(); 2027 } 2028 } 2029 2030 if (!Type->isPointerType()) 2031 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2032 << Type << Ex.get()->getSourceRange()); 2033 2034 QualType Pointee = Type->getAs<PointerType>()->getPointeeType(); 2035 QualType PointeeElem = Context.getBaseElementType(Pointee); 2036 2037 if (unsigned AddressSpace = Pointee.getAddressSpace()) 2038 return Diag(Ex.get()->getLocStart(), 2039 diag::err_address_space_qualified_delete) 2040 << Pointee.getUnqualifiedType() << AddressSpace; 2041 2042 CXXRecordDecl *PointeeRD = 0; 2043 if (Pointee->isVoidType() && !isSFINAEContext()) { 2044 // The C++ standard bans deleting a pointer to a non-object type, which 2045 // effectively bans deletion of "void*". However, most compilers support 2046 // this, so we treat it as a warning unless we're in a SFINAE context. 2047 Diag(StartLoc, diag::ext_delete_void_ptr_operand) 2048 << Type << Ex.get()->getSourceRange(); 2049 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) { 2050 return ExprError(Diag(StartLoc, diag::err_delete_operand) 2051 << Type << Ex.get()->getSourceRange()); 2052 } else if (!Pointee->isDependentType()) { 2053 if (!RequireCompleteType(StartLoc, Pointee, 2054 PDiag(diag::warn_delete_incomplete) 2055 << Ex.get()->getSourceRange())) { 2056 if (const RecordType *RT = PointeeElem->getAs<RecordType>()) 2057 PointeeRD = cast<CXXRecordDecl>(RT->getDecl()); 2058 } 2059 } 2060 2061 // C++ [expr.delete]p2: 2062 // [Note: a pointer to a const type can be the operand of a 2063 // delete-expression; it is not necessary to cast away the constness 2064 // (5.2.11) of the pointer expression before it is used as the operand 2065 // of the delete-expression. ] 2066 if (!Context.hasSameType(Ex.get()->getType(), Context.VoidPtrTy)) 2067 Ex = Owned(ImplicitCastExpr::Create(Context, Context.VoidPtrTy, 2068 CK_BitCast, Ex.take(), 0, VK_RValue)); 2069 2070 if (Pointee->isArrayType() && !ArrayForm) { 2071 Diag(StartLoc, diag::warn_delete_array_type) 2072 << Type << Ex.get()->getSourceRange() 2073 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]"); 2074 ArrayForm = true; 2075 } 2076 2077 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName( 2078 ArrayForm ? OO_Array_Delete : OO_Delete); 2079 2080 if (PointeeRD) { 2081 if (!UseGlobal && 2082 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName, 2083 OperatorDelete)) 2084 return ExprError(); 2085 2086 // If we're allocating an array of records, check whether the 2087 // usual operator delete[] has a size_t parameter. 2088 if (ArrayForm) { 2089 // If the user specifically asked to use the global allocator, 2090 // we'll need to do the lookup into the class. 2091 if (UseGlobal) 2092 UsualArrayDeleteWantsSize = 2093 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem); 2094 2095 // Otherwise, the usual operator delete[] should be the 2096 // function we just found. 2097 else if (isa<CXXMethodDecl>(OperatorDelete)) 2098 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2); 2099 } 2100 2101 if (!PointeeRD->hasIrrelevantDestructor()) 2102 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2103 MarkFunctionReferenced(StartLoc, 2104 const_cast<CXXDestructorDecl*>(Dtor)); 2105 DiagnoseUseOfDecl(Dtor, StartLoc); 2106 } 2107 2108 // C++ [expr.delete]p3: 2109 // In the first alternative (delete object), if the static type of the 2110 // object to be deleted is different from its dynamic type, the static 2111 // type shall be a base class of the dynamic type of the object to be 2112 // deleted and the static type shall have a virtual destructor or the 2113 // behavior is undefined. 2114 // 2115 // Note: a final class cannot be derived from, no issue there 2116 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) { 2117 CXXDestructorDecl *dtor = PointeeRD->getDestructor(); 2118 if (dtor && !dtor->isVirtual()) { 2119 if (PointeeRD->isAbstract()) { 2120 // If the class is abstract, we warn by default, because we're 2121 // sure the code has undefined behavior. 2122 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor) 2123 << PointeeElem; 2124 } else if (!ArrayForm) { 2125 // Otherwise, if this is not an array delete, it's a bit suspect, 2126 // but not necessarily wrong. 2127 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem; 2128 } 2129 } 2130 } 2131 2132 } else if (getLangOpts().ObjCAutoRefCount && 2133 PointeeElem->isObjCLifetimeType() && 2134 (PointeeElem.getObjCLifetime() == Qualifiers::OCL_Strong || 2135 PointeeElem.getObjCLifetime() == Qualifiers::OCL_Weak) && 2136 ArrayForm) { 2137 Diag(StartLoc, diag::warn_err_new_delete_object_array) 2138 << 1 << PointeeElem; 2139 } 2140 2141 if (!OperatorDelete) { 2142 // Look for a global declaration. 2143 DeclareGlobalNewDelete(); 2144 DeclContext *TUDecl = Context.getTranslationUnitDecl(); 2145 Expr *Arg = Ex.get(); 2146 if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName, 2147 &Arg, 1, TUDecl, /*AllowMissing=*/false, 2148 OperatorDelete)) 2149 return ExprError(); 2150 } 2151 2152 MarkFunctionReferenced(StartLoc, OperatorDelete); 2153 2154 // Check access and ambiguity of operator delete and destructor. 2155 if (PointeeRD) { 2156 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) { 2157 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor, 2158 PDiag(diag::err_access_dtor) << PointeeElem); 2159 } 2160 } 2161 2162 } 2163 2164 return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm, 2165 ArrayFormAsWritten, 2166 UsualArrayDeleteWantsSize, 2167 OperatorDelete, Ex.take(), StartLoc)); 2168} 2169 2170/// \brief Check the use of the given variable as a C++ condition in an if, 2171/// while, do-while, or switch statement. 2172ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar, 2173 SourceLocation StmtLoc, 2174 bool ConvertToBoolean) { 2175 QualType T = ConditionVar->getType(); 2176 2177 // C++ [stmt.select]p2: 2178 // The declarator shall not specify a function or an array. 2179 if (T->isFunctionType()) 2180 return ExprError(Diag(ConditionVar->getLocation(), 2181 diag::err_invalid_use_of_function_type) 2182 << ConditionVar->getSourceRange()); 2183 else if (T->isArrayType()) 2184 return ExprError(Diag(ConditionVar->getLocation(), 2185 diag::err_invalid_use_of_array_type) 2186 << ConditionVar->getSourceRange()); 2187 2188 ExprResult Condition = 2189 Owned(DeclRefExpr::Create(Context, NestedNameSpecifierLoc(), 2190 SourceLocation(), 2191 ConditionVar, 2192 /*enclosing*/ false, 2193 ConditionVar->getLocation(), 2194 ConditionVar->getType().getNonReferenceType(), 2195 VK_LValue)); 2196 2197 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get())); 2198 2199 if (ConvertToBoolean) { 2200 Condition = CheckBooleanCondition(Condition.take(), StmtLoc); 2201 if (Condition.isInvalid()) 2202 return ExprError(); 2203 } 2204 2205 return move(Condition); 2206} 2207 2208/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid. 2209ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) { 2210 // C++ 6.4p4: 2211 // The value of a condition that is an initialized declaration in a statement 2212 // other than a switch statement is the value of the declared variable 2213 // implicitly converted to type bool. If that conversion is ill-formed, the 2214 // program is ill-formed. 2215 // The value of a condition that is an expression is the value of the 2216 // expression, implicitly converted to bool. 2217 // 2218 return PerformContextuallyConvertToBool(CondExpr); 2219} 2220 2221/// Helper function to determine whether this is the (deprecated) C++ 2222/// conversion from a string literal to a pointer to non-const char or 2223/// non-const wchar_t (for narrow and wide string literals, 2224/// respectively). 2225bool 2226Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) { 2227 // Look inside the implicit cast, if it exists. 2228 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From)) 2229 From = Cast->getSubExpr(); 2230 2231 // A string literal (2.13.4) that is not a wide string literal can 2232 // be converted to an rvalue of type "pointer to char"; a wide 2233 // string literal can be converted to an rvalue of type "pointer 2234 // to wchar_t" (C++ 4.2p2). 2235 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens())) 2236 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) 2237 if (const BuiltinType *ToPointeeType 2238 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) { 2239 // This conversion is considered only when there is an 2240 // explicit appropriate pointer target type (C++ 4.2p2). 2241 if (!ToPtrType->getPointeeType().hasQualifiers()) { 2242 switch (StrLit->getKind()) { 2243 case StringLiteral::UTF8: 2244 case StringLiteral::UTF16: 2245 case StringLiteral::UTF32: 2246 // We don't allow UTF literals to be implicitly converted 2247 break; 2248 case StringLiteral::Ascii: 2249 return (ToPointeeType->getKind() == BuiltinType::Char_U || 2250 ToPointeeType->getKind() == BuiltinType::Char_S); 2251 case StringLiteral::Wide: 2252 return ToPointeeType->isWideCharType(); 2253 } 2254 } 2255 } 2256 2257 return false; 2258} 2259 2260static ExprResult BuildCXXCastArgument(Sema &S, 2261 SourceLocation CastLoc, 2262 QualType Ty, 2263 CastKind Kind, 2264 CXXMethodDecl *Method, 2265 DeclAccessPair FoundDecl, 2266 bool HadMultipleCandidates, 2267 Expr *From) { 2268 switch (Kind) { 2269 default: llvm_unreachable("Unhandled cast kind!"); 2270 case CK_ConstructorConversion: { 2271 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method); 2272 ASTOwningVector<Expr*> ConstructorArgs(S); 2273 2274 if (S.CompleteConstructorCall(Constructor, 2275 MultiExprArg(&From, 1), 2276 CastLoc, ConstructorArgs)) 2277 return ExprError(); 2278 2279 S.CheckConstructorAccess(CastLoc, Constructor, 2280 InitializedEntity::InitializeTemporary(Ty), 2281 Constructor->getAccess()); 2282 2283 ExprResult Result 2284 = S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method), 2285 move_arg(ConstructorArgs), 2286 HadMultipleCandidates, /*ZeroInit*/ false, 2287 CXXConstructExpr::CK_Complete, SourceRange()); 2288 if (Result.isInvalid()) 2289 return ExprError(); 2290 2291 return S.MaybeBindToTemporary(Result.takeAs<Expr>()); 2292 } 2293 2294 case CK_UserDefinedConversion: { 2295 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!"); 2296 2297 // Create an implicit call expr that calls it. 2298 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method); 2299 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv, 2300 HadMultipleCandidates); 2301 if (Result.isInvalid()) 2302 return ExprError(); 2303 // Record usage of conversion in an implicit cast. 2304 Result = S.Owned(ImplicitCastExpr::Create(S.Context, 2305 Result.get()->getType(), 2306 CK_UserDefinedConversion, 2307 Result.get(), 0, 2308 Result.get()->getValueKind())); 2309 2310 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ 0, FoundDecl); 2311 2312 return S.MaybeBindToTemporary(Result.get()); 2313 } 2314 } 2315} 2316 2317/// PerformImplicitConversion - Perform an implicit conversion of the 2318/// expression From to the type ToType using the pre-computed implicit 2319/// conversion sequence ICS. Returns the converted 2320/// expression. Action is the kind of conversion we're performing, 2321/// used in the error message. 2322ExprResult 2323Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2324 const ImplicitConversionSequence &ICS, 2325 AssignmentAction Action, 2326 CheckedConversionKind CCK) { 2327 switch (ICS.getKind()) { 2328 case ImplicitConversionSequence::StandardConversion: { 2329 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard, 2330 Action, CCK); 2331 if (Res.isInvalid()) 2332 return ExprError(); 2333 From = Res.take(); 2334 break; 2335 } 2336 2337 case ImplicitConversionSequence::UserDefinedConversion: { 2338 2339 FunctionDecl *FD = ICS.UserDefined.ConversionFunction; 2340 CastKind CastKind; 2341 QualType BeforeToType; 2342 assert(FD && "FIXME: aggregate initialization from init list"); 2343 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) { 2344 CastKind = CK_UserDefinedConversion; 2345 2346 // If the user-defined conversion is specified by a conversion function, 2347 // the initial standard conversion sequence converts the source type to 2348 // the implicit object parameter of the conversion function. 2349 BeforeToType = Context.getTagDeclType(Conv->getParent()); 2350 } else { 2351 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD); 2352 CastKind = CK_ConstructorConversion; 2353 // Do no conversion if dealing with ... for the first conversion. 2354 if (!ICS.UserDefined.EllipsisConversion) { 2355 // If the user-defined conversion is specified by a constructor, the 2356 // initial standard conversion sequence converts the source type to the 2357 // type required by the argument of the constructor 2358 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType(); 2359 } 2360 } 2361 // Watch out for elipsis conversion. 2362 if (!ICS.UserDefined.EllipsisConversion) { 2363 ExprResult Res = 2364 PerformImplicitConversion(From, BeforeToType, 2365 ICS.UserDefined.Before, AA_Converting, 2366 CCK); 2367 if (Res.isInvalid()) 2368 return ExprError(); 2369 From = Res.take(); 2370 } 2371 2372 ExprResult CastArg 2373 = BuildCXXCastArgument(*this, 2374 From->getLocStart(), 2375 ToType.getNonReferenceType(), 2376 CastKind, cast<CXXMethodDecl>(FD), 2377 ICS.UserDefined.FoundConversionFunction, 2378 ICS.UserDefined.HadMultipleCandidates, 2379 From); 2380 2381 if (CastArg.isInvalid()) 2382 return ExprError(); 2383 2384 From = CastArg.take(); 2385 2386 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After, 2387 AA_Converting, CCK); 2388 } 2389 2390 case ImplicitConversionSequence::AmbiguousConversion: 2391 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(), 2392 PDiag(diag::err_typecheck_ambiguous_condition) 2393 << From->getSourceRange()); 2394 return ExprError(); 2395 2396 case ImplicitConversionSequence::EllipsisConversion: 2397 llvm_unreachable("Cannot perform an ellipsis conversion"); 2398 2399 case ImplicitConversionSequence::BadConversion: 2400 return ExprError(); 2401 } 2402 2403 // Everything went well. 2404 return Owned(From); 2405} 2406 2407/// PerformImplicitConversion - Perform an implicit conversion of the 2408/// expression From to the type ToType by following the standard 2409/// conversion sequence SCS. Returns the converted 2410/// expression. Flavor is the context in which we're performing this 2411/// conversion, for use in error messages. 2412ExprResult 2413Sema::PerformImplicitConversion(Expr *From, QualType ToType, 2414 const StandardConversionSequence& SCS, 2415 AssignmentAction Action, 2416 CheckedConversionKind CCK) { 2417 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast); 2418 2419 // Overall FIXME: we are recomputing too many types here and doing far too 2420 // much extra work. What this means is that we need to keep track of more 2421 // information that is computed when we try the implicit conversion initially, 2422 // so that we don't need to recompute anything here. 2423 QualType FromType = From->getType(); 2424 2425 if (SCS.CopyConstructor) { 2426 // FIXME: When can ToType be a reference type? 2427 assert(!ToType->isReferenceType()); 2428 if (SCS.Second == ICK_Derived_To_Base) { 2429 ASTOwningVector<Expr*> ConstructorArgs(*this); 2430 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor), 2431 MultiExprArg(*this, &From, 1), 2432 /*FIXME:ConstructLoc*/SourceLocation(), 2433 ConstructorArgs)) 2434 return ExprError(); 2435 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2436 ToType, SCS.CopyConstructor, 2437 move_arg(ConstructorArgs), 2438 /*HadMultipleCandidates*/ false, 2439 /*ZeroInit*/ false, 2440 CXXConstructExpr::CK_Complete, 2441 SourceRange()); 2442 } 2443 return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(), 2444 ToType, SCS.CopyConstructor, 2445 MultiExprArg(*this, &From, 1), 2446 /*HadMultipleCandidates*/ false, 2447 /*ZeroInit*/ false, 2448 CXXConstructExpr::CK_Complete, 2449 SourceRange()); 2450 } 2451 2452 // Resolve overloaded function references. 2453 if (Context.hasSameType(FromType, Context.OverloadTy)) { 2454 DeclAccessPair Found; 2455 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, 2456 true, Found); 2457 if (!Fn) 2458 return ExprError(); 2459 2460 if (DiagnoseUseOfDecl(Fn, From->getLocStart())) 2461 return ExprError(); 2462 2463 From = FixOverloadedFunctionReference(From, Found, Fn); 2464 FromType = From->getType(); 2465 } 2466 2467 // Perform the first implicit conversion. 2468 switch (SCS.First) { 2469 case ICK_Identity: 2470 // Nothing to do. 2471 break; 2472 2473 case ICK_Lvalue_To_Rvalue: { 2474 assert(From->getObjectKind() != OK_ObjCProperty); 2475 FromType = FromType.getUnqualifiedType(); 2476 ExprResult FromRes = DefaultLvalueConversion(From); 2477 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!"); 2478 From = FromRes.take(); 2479 break; 2480 } 2481 2482 case ICK_Array_To_Pointer: 2483 FromType = Context.getArrayDecayedType(FromType); 2484 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, 2485 VK_RValue, /*BasePath=*/0, CCK).take(); 2486 break; 2487 2488 case ICK_Function_To_Pointer: 2489 FromType = Context.getPointerType(FromType); 2490 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay, 2491 VK_RValue, /*BasePath=*/0, CCK).take(); 2492 break; 2493 2494 default: 2495 llvm_unreachable("Improper first standard conversion"); 2496 } 2497 2498 // Perform the second implicit conversion 2499 switch (SCS.Second) { 2500 case ICK_Identity: 2501 // If both sides are functions (or pointers/references to them), there could 2502 // be incompatible exception declarations. 2503 if (CheckExceptionSpecCompatibility(From, ToType)) 2504 return ExprError(); 2505 // Nothing else to do. 2506 break; 2507 2508 case ICK_NoReturn_Adjustment: 2509 // If both sides are functions (or pointers/references to them), there could 2510 // be incompatible exception declarations. 2511 if (CheckExceptionSpecCompatibility(From, ToType)) 2512 return ExprError(); 2513 2514 From = ImpCastExprToType(From, ToType, CK_NoOp, 2515 VK_RValue, /*BasePath=*/0, CCK).take(); 2516 break; 2517 2518 case ICK_Integral_Promotion: 2519 case ICK_Integral_Conversion: 2520 From = ImpCastExprToType(From, ToType, CK_IntegralCast, 2521 VK_RValue, /*BasePath=*/0, CCK).take(); 2522 break; 2523 2524 case ICK_Floating_Promotion: 2525 case ICK_Floating_Conversion: 2526 From = ImpCastExprToType(From, ToType, CK_FloatingCast, 2527 VK_RValue, /*BasePath=*/0, CCK).take(); 2528 break; 2529 2530 case ICK_Complex_Promotion: 2531 case ICK_Complex_Conversion: { 2532 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType(); 2533 QualType ToEl = ToType->getAs<ComplexType>()->getElementType(); 2534 CastKind CK; 2535 if (FromEl->isRealFloatingType()) { 2536 if (ToEl->isRealFloatingType()) 2537 CK = CK_FloatingComplexCast; 2538 else 2539 CK = CK_FloatingComplexToIntegralComplex; 2540 } else if (ToEl->isRealFloatingType()) { 2541 CK = CK_IntegralComplexToFloatingComplex; 2542 } else { 2543 CK = CK_IntegralComplexCast; 2544 } 2545 From = ImpCastExprToType(From, ToType, CK, 2546 VK_RValue, /*BasePath=*/0, CCK).take(); 2547 break; 2548 } 2549 2550 case ICK_Floating_Integral: 2551 if (ToType->isRealFloatingType()) 2552 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, 2553 VK_RValue, /*BasePath=*/0, CCK).take(); 2554 else 2555 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, 2556 VK_RValue, /*BasePath=*/0, CCK).take(); 2557 break; 2558 2559 case ICK_Compatible_Conversion: 2560 From = ImpCastExprToType(From, ToType, CK_NoOp, 2561 VK_RValue, /*BasePath=*/0, CCK).take(); 2562 break; 2563 2564 case ICK_Writeback_Conversion: 2565 case ICK_Pointer_Conversion: { 2566 if (SCS.IncompatibleObjC && Action != AA_Casting) { 2567 // Diagnose incompatible Objective-C conversions 2568 if (Action == AA_Initializing || Action == AA_Assigning) 2569 Diag(From->getLocStart(), 2570 diag::ext_typecheck_convert_incompatible_pointer) 2571 << ToType << From->getType() << Action 2572 << From->getSourceRange() << 0; 2573 else 2574 Diag(From->getLocStart(), 2575 diag::ext_typecheck_convert_incompatible_pointer) 2576 << From->getType() << ToType << Action 2577 << From->getSourceRange() << 0; 2578 2579 if (From->getType()->isObjCObjectPointerType() && 2580 ToType->isObjCObjectPointerType()) 2581 EmitRelatedResultTypeNote(From); 2582 } 2583 else if (getLangOpts().ObjCAutoRefCount && 2584 !CheckObjCARCUnavailableWeakConversion(ToType, 2585 From->getType())) { 2586 if (Action == AA_Initializing) 2587 Diag(From->getLocStart(), 2588 diag::err_arc_weak_unavailable_assign); 2589 else 2590 Diag(From->getLocStart(), 2591 diag::err_arc_convesion_of_weak_unavailable) 2592 << (Action == AA_Casting) << From->getType() << ToType 2593 << From->getSourceRange(); 2594 } 2595 2596 CastKind Kind = CK_Invalid; 2597 CXXCastPath BasePath; 2598 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2599 return ExprError(); 2600 2601 // Make sure we extend blocks if necessary. 2602 // FIXME: doing this here is really ugly. 2603 if (Kind == CK_BlockPointerToObjCPointerCast) { 2604 ExprResult E = From; 2605 (void) PrepareCastToObjCObjectPointer(E); 2606 From = E.take(); 2607 } 2608 2609 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2610 .take(); 2611 break; 2612 } 2613 2614 case ICK_Pointer_Member: { 2615 CastKind Kind = CK_Invalid; 2616 CXXCastPath BasePath; 2617 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle)) 2618 return ExprError(); 2619 if (CheckExceptionSpecCompatibility(From, ToType)) 2620 return ExprError(); 2621 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK) 2622 .take(); 2623 break; 2624 } 2625 2626 case ICK_Boolean_Conversion: 2627 // Perform half-to-boolean conversion via float. 2628 if (From->getType()->isHalfType()) { 2629 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).take(); 2630 FromType = Context.FloatTy; 2631 } 2632 2633 From = ImpCastExprToType(From, Context.BoolTy, 2634 ScalarTypeToBooleanCastKind(FromType), 2635 VK_RValue, /*BasePath=*/0, CCK).take(); 2636 break; 2637 2638 case ICK_Derived_To_Base: { 2639 CXXCastPath BasePath; 2640 if (CheckDerivedToBaseConversion(From->getType(), 2641 ToType.getNonReferenceType(), 2642 From->getLocStart(), 2643 From->getSourceRange(), 2644 &BasePath, 2645 CStyle)) 2646 return ExprError(); 2647 2648 From = ImpCastExprToType(From, ToType.getNonReferenceType(), 2649 CK_DerivedToBase, From->getValueKind(), 2650 &BasePath, CCK).take(); 2651 break; 2652 } 2653 2654 case ICK_Vector_Conversion: 2655 From = ImpCastExprToType(From, ToType, CK_BitCast, 2656 VK_RValue, /*BasePath=*/0, CCK).take(); 2657 break; 2658 2659 case ICK_Vector_Splat: 2660 From = ImpCastExprToType(From, ToType, CK_VectorSplat, 2661 VK_RValue, /*BasePath=*/0, CCK).take(); 2662 break; 2663 2664 case ICK_Complex_Real: 2665 // Case 1. x -> _Complex y 2666 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) { 2667 QualType ElType = ToComplex->getElementType(); 2668 bool isFloatingComplex = ElType->isRealFloatingType(); 2669 2670 // x -> y 2671 if (Context.hasSameUnqualifiedType(ElType, From->getType())) { 2672 // do nothing 2673 } else if (From->getType()->isRealFloatingType()) { 2674 From = ImpCastExprToType(From, ElType, 2675 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).take(); 2676 } else { 2677 assert(From->getType()->isIntegerType()); 2678 From = ImpCastExprToType(From, ElType, 2679 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).take(); 2680 } 2681 // y -> _Complex y 2682 From = ImpCastExprToType(From, ToType, 2683 isFloatingComplex ? CK_FloatingRealToComplex 2684 : CK_IntegralRealToComplex).take(); 2685 2686 // Case 2. _Complex x -> y 2687 } else { 2688 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>(); 2689 assert(FromComplex); 2690 2691 QualType ElType = FromComplex->getElementType(); 2692 bool isFloatingComplex = ElType->isRealFloatingType(); 2693 2694 // _Complex x -> x 2695 From = ImpCastExprToType(From, ElType, 2696 isFloatingComplex ? CK_FloatingComplexToReal 2697 : CK_IntegralComplexToReal, 2698 VK_RValue, /*BasePath=*/0, CCK).take(); 2699 2700 // x -> y 2701 if (Context.hasSameUnqualifiedType(ElType, ToType)) { 2702 // do nothing 2703 } else if (ToType->isRealFloatingType()) { 2704 From = ImpCastExprToType(From, ToType, 2705 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating, 2706 VK_RValue, /*BasePath=*/0, CCK).take(); 2707 } else { 2708 assert(ToType->isIntegerType()); 2709 From = ImpCastExprToType(From, ToType, 2710 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast, 2711 VK_RValue, /*BasePath=*/0, CCK).take(); 2712 } 2713 } 2714 break; 2715 2716 case ICK_Block_Pointer_Conversion: { 2717 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast, 2718 VK_RValue, /*BasePath=*/0, CCK).take(); 2719 break; 2720 } 2721 2722 case ICK_TransparentUnionConversion: { 2723 ExprResult FromRes = Owned(From); 2724 Sema::AssignConvertType ConvTy = 2725 CheckTransparentUnionArgumentConstraints(ToType, FromRes); 2726 if (FromRes.isInvalid()) 2727 return ExprError(); 2728 From = FromRes.take(); 2729 assert ((ConvTy == Sema::Compatible) && 2730 "Improper transparent union conversion"); 2731 (void)ConvTy; 2732 break; 2733 } 2734 2735 case ICK_Lvalue_To_Rvalue: 2736 case ICK_Array_To_Pointer: 2737 case ICK_Function_To_Pointer: 2738 case ICK_Qualification: 2739 case ICK_Num_Conversion_Kinds: 2740 llvm_unreachable("Improper second standard conversion"); 2741 } 2742 2743 switch (SCS.Third) { 2744 case ICK_Identity: 2745 // Nothing to do. 2746 break; 2747 2748 case ICK_Qualification: { 2749 // The qualification keeps the category of the inner expression, unless the 2750 // target type isn't a reference. 2751 ExprValueKind VK = ToType->isReferenceType() ? 2752 From->getValueKind() : VK_RValue; 2753 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), 2754 CK_NoOp, VK, /*BasePath=*/0, CCK).take(); 2755 2756 if (SCS.DeprecatedStringLiteralToCharPtr && 2757 !getLangOpts().WritableStrings) 2758 Diag(From->getLocStart(), diag::warn_deprecated_string_literal_conversion) 2759 << ToType.getNonReferenceType(); 2760 2761 break; 2762 } 2763 2764 default: 2765 llvm_unreachable("Improper third standard conversion"); 2766 } 2767 2768 return Owned(From); 2769} 2770 2771ExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait UTT, 2772 SourceLocation KWLoc, 2773 ParsedType Ty, 2774 SourceLocation RParen) { 2775 TypeSourceInfo *TSInfo; 2776 QualType T = GetTypeFromParser(Ty, &TSInfo); 2777 2778 if (!TSInfo) 2779 TSInfo = Context.getTrivialTypeSourceInfo(T); 2780 return BuildUnaryTypeTrait(UTT, KWLoc, TSInfo, RParen); 2781} 2782 2783/// \brief Check the completeness of a type in a unary type trait. 2784/// 2785/// If the particular type trait requires a complete type, tries to complete 2786/// it. If completing the type fails, a diagnostic is emitted and false 2787/// returned. If completing the type succeeds or no completion was required, 2788/// returns true. 2789static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, 2790 UnaryTypeTrait UTT, 2791 SourceLocation Loc, 2792 QualType ArgTy) { 2793 // C++0x [meta.unary.prop]p3: 2794 // For all of the class templates X declared in this Clause, instantiating 2795 // that template with a template argument that is a class template 2796 // specialization may result in the implicit instantiation of the template 2797 // argument if and only if the semantics of X require that the argument 2798 // must be a complete type. 2799 // We apply this rule to all the type trait expressions used to implement 2800 // these class templates. We also try to follow any GCC documented behavior 2801 // in these expressions to ensure portability of standard libraries. 2802 switch (UTT) { 2803 // is_complete_type somewhat obviously cannot require a complete type. 2804 case UTT_IsCompleteType: 2805 // Fall-through 2806 2807 // These traits are modeled on the type predicates in C++0x 2808 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as 2809 // requiring a complete type, as whether or not they return true cannot be 2810 // impacted by the completeness of the type. 2811 case UTT_IsVoid: 2812 case UTT_IsIntegral: 2813 case UTT_IsFloatingPoint: 2814 case UTT_IsArray: 2815 case UTT_IsPointer: 2816 case UTT_IsLvalueReference: 2817 case UTT_IsRvalueReference: 2818 case UTT_IsMemberFunctionPointer: 2819 case UTT_IsMemberObjectPointer: 2820 case UTT_IsEnum: 2821 case UTT_IsUnion: 2822 case UTT_IsClass: 2823 case UTT_IsFunction: 2824 case UTT_IsReference: 2825 case UTT_IsArithmetic: 2826 case UTT_IsFundamental: 2827 case UTT_IsObject: 2828 case UTT_IsScalar: 2829 case UTT_IsCompound: 2830 case UTT_IsMemberPointer: 2831 // Fall-through 2832 2833 // These traits are modeled on type predicates in C++0x [meta.unary.prop] 2834 // which requires some of its traits to have the complete type. However, 2835 // the completeness of the type cannot impact these traits' semantics, and 2836 // so they don't require it. This matches the comments on these traits in 2837 // Table 49. 2838 case UTT_IsConst: 2839 case UTT_IsVolatile: 2840 case UTT_IsSigned: 2841 case UTT_IsUnsigned: 2842 return true; 2843 2844 // C++0x [meta.unary.prop] Table 49 requires the following traits to be 2845 // applied to a complete type. 2846 case UTT_IsTrivial: 2847 case UTT_IsTriviallyCopyable: 2848 case UTT_IsStandardLayout: 2849 case UTT_IsPOD: 2850 case UTT_IsLiteral: 2851 case UTT_IsEmpty: 2852 case UTT_IsPolymorphic: 2853 case UTT_IsAbstract: 2854 // Fall-through 2855 2856 // These traits require a complete type. 2857 case UTT_IsFinal: 2858 2859 // These trait expressions are designed to help implement predicates in 2860 // [meta.unary.prop] despite not being named the same. They are specified 2861 // by both GCC and the Embarcadero C++ compiler, and require the complete 2862 // type due to the overarching C++0x type predicates being implemented 2863 // requiring the complete type. 2864 case UTT_HasNothrowAssign: 2865 case UTT_HasNothrowConstructor: 2866 case UTT_HasNothrowCopy: 2867 case UTT_HasTrivialAssign: 2868 case UTT_HasTrivialDefaultConstructor: 2869 case UTT_HasTrivialCopy: 2870 case UTT_HasTrivialDestructor: 2871 case UTT_HasVirtualDestructor: 2872 // Arrays of unknown bound are expressly allowed. 2873 QualType ElTy = ArgTy; 2874 if (ArgTy->isIncompleteArrayType()) 2875 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType(); 2876 2877 // The void type is expressly allowed. 2878 if (ElTy->isVoidType()) 2879 return true; 2880 2881 return !S.RequireCompleteType( 2882 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr); 2883 } 2884 llvm_unreachable("Type trait not handled by switch"); 2885} 2886 2887static bool EvaluateUnaryTypeTrait(Sema &Self, UnaryTypeTrait UTT, 2888 SourceLocation KeyLoc, QualType T) { 2889 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 2890 2891 ASTContext &C = Self.Context; 2892 switch(UTT) { 2893 // Type trait expressions corresponding to the primary type category 2894 // predicates in C++0x [meta.unary.cat]. 2895 case UTT_IsVoid: 2896 return T->isVoidType(); 2897 case UTT_IsIntegral: 2898 return T->isIntegralType(C); 2899 case UTT_IsFloatingPoint: 2900 return T->isFloatingType(); 2901 case UTT_IsArray: 2902 return T->isArrayType(); 2903 case UTT_IsPointer: 2904 return T->isPointerType(); 2905 case UTT_IsLvalueReference: 2906 return T->isLValueReferenceType(); 2907 case UTT_IsRvalueReference: 2908 return T->isRValueReferenceType(); 2909 case UTT_IsMemberFunctionPointer: 2910 return T->isMemberFunctionPointerType(); 2911 case UTT_IsMemberObjectPointer: 2912 return T->isMemberDataPointerType(); 2913 case UTT_IsEnum: 2914 return T->isEnumeralType(); 2915 case UTT_IsUnion: 2916 return T->isUnionType(); 2917 case UTT_IsClass: 2918 return T->isClassType() || T->isStructureType(); 2919 case UTT_IsFunction: 2920 return T->isFunctionType(); 2921 2922 // Type trait expressions which correspond to the convenient composition 2923 // predicates in C++0x [meta.unary.comp]. 2924 case UTT_IsReference: 2925 return T->isReferenceType(); 2926 case UTT_IsArithmetic: 2927 return T->isArithmeticType() && !T->isEnumeralType(); 2928 case UTT_IsFundamental: 2929 return T->isFundamentalType(); 2930 case UTT_IsObject: 2931 return T->isObjectType(); 2932 case UTT_IsScalar: 2933 // Note: semantic analysis depends on Objective-C lifetime types to be 2934 // considered scalar types. However, such types do not actually behave 2935 // like scalar types at run time (since they may require retain/release 2936 // operations), so we report them as non-scalar. 2937 if (T->isObjCLifetimeType()) { 2938 switch (T.getObjCLifetime()) { 2939 case Qualifiers::OCL_None: 2940 case Qualifiers::OCL_ExplicitNone: 2941 return true; 2942 2943 case Qualifiers::OCL_Strong: 2944 case Qualifiers::OCL_Weak: 2945 case Qualifiers::OCL_Autoreleasing: 2946 return false; 2947 } 2948 } 2949 2950 return T->isScalarType(); 2951 case UTT_IsCompound: 2952 return T->isCompoundType(); 2953 case UTT_IsMemberPointer: 2954 return T->isMemberPointerType(); 2955 2956 // Type trait expressions which correspond to the type property predicates 2957 // in C++0x [meta.unary.prop]. 2958 case UTT_IsConst: 2959 return T.isConstQualified(); 2960 case UTT_IsVolatile: 2961 return T.isVolatileQualified(); 2962 case UTT_IsTrivial: 2963 return T.isTrivialType(Self.Context); 2964 case UTT_IsTriviallyCopyable: 2965 return T.isTriviallyCopyableType(Self.Context); 2966 case UTT_IsStandardLayout: 2967 return T->isStandardLayoutType(); 2968 case UTT_IsPOD: 2969 return T.isPODType(Self.Context); 2970 case UTT_IsLiteral: 2971 return T->isLiteralType(); 2972 case UTT_IsEmpty: 2973 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2974 return !RD->isUnion() && RD->isEmpty(); 2975 return false; 2976 case UTT_IsPolymorphic: 2977 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2978 return RD->isPolymorphic(); 2979 return false; 2980 case UTT_IsAbstract: 2981 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2982 return RD->isAbstract(); 2983 return false; 2984 case UTT_IsFinal: 2985 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) 2986 return RD->hasAttr<FinalAttr>(); 2987 return false; 2988 case UTT_IsSigned: 2989 return T->isSignedIntegerType(); 2990 case UTT_IsUnsigned: 2991 return T->isUnsignedIntegerType(); 2992 2993 // Type trait expressions which query classes regarding their construction, 2994 // destruction, and copying. Rather than being based directly on the 2995 // related type predicates in the standard, they are specified by both 2996 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those 2997 // specifications. 2998 // 2999 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html 3000 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3001 case UTT_HasTrivialDefaultConstructor: 3002 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3003 // If __is_pod (type) is true then the trait is true, else if type is 3004 // a cv class or union type (or array thereof) with a trivial default 3005 // constructor ([class.ctor]) then the trait is true, else it is false. 3006 if (T.isPODType(Self.Context)) 3007 return true; 3008 if (const RecordType *RT = 3009 C.getBaseElementType(T)->getAs<RecordType>()) 3010 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDefaultConstructor(); 3011 return false; 3012 case UTT_HasTrivialCopy: 3013 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3014 // If __is_pod (type) is true or type is a reference type then 3015 // the trait is true, else if type is a cv class or union type 3016 // with a trivial copy constructor ([class.copy]) then the trait 3017 // is true, else it is false. 3018 if (T.isPODType(Self.Context) || T->isReferenceType()) 3019 return true; 3020 if (const RecordType *RT = T->getAs<RecordType>()) 3021 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyConstructor(); 3022 return false; 3023 case UTT_HasTrivialAssign: 3024 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3025 // If type is const qualified or is a reference type then the 3026 // trait is false. Otherwise if __is_pod (type) is true then the 3027 // trait is true, else if type is a cv class or union type with 3028 // a trivial copy assignment ([class.copy]) then the trait is 3029 // true, else it is false. 3030 // Note: the const and reference restrictions are interesting, 3031 // given that const and reference members don't prevent a class 3032 // from having a trivial copy assignment operator (but do cause 3033 // errors if the copy assignment operator is actually used, q.v. 3034 // [class.copy]p12). 3035 3036 if (C.getBaseElementType(T).isConstQualified()) 3037 return false; 3038 if (T.isPODType(Self.Context)) 3039 return true; 3040 if (const RecordType *RT = T->getAs<RecordType>()) 3041 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyAssignment(); 3042 return false; 3043 case UTT_HasTrivialDestructor: 3044 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3045 // If __is_pod (type) is true or type is a reference type 3046 // then the trait is true, else if type is a cv class or union 3047 // type (or array thereof) with a trivial destructor 3048 // ([class.dtor]) then the trait is true, else it is 3049 // false. 3050 if (T.isPODType(Self.Context) || T->isReferenceType()) 3051 return true; 3052 3053 // Objective-C++ ARC: autorelease types don't require destruction. 3054 if (T->isObjCLifetimeType() && 3055 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) 3056 return true; 3057 3058 if (const RecordType *RT = 3059 C.getBaseElementType(T)->getAs<RecordType>()) 3060 return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDestructor(); 3061 return false; 3062 // TODO: Propagate nothrowness for implicitly declared special members. 3063 case UTT_HasNothrowAssign: 3064 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3065 // If type is const qualified or is a reference type then the 3066 // trait is false. Otherwise if __has_trivial_assign (type) 3067 // is true then the trait is true, else if type is a cv class 3068 // or union type with copy assignment operators that are known 3069 // not to throw an exception then the trait is true, else it is 3070 // false. 3071 if (C.getBaseElementType(T).isConstQualified()) 3072 return false; 3073 if (T->isReferenceType()) 3074 return false; 3075 if (T.isPODType(Self.Context) || T->isObjCLifetimeType()) 3076 return true; 3077 if (const RecordType *RT = T->getAs<RecordType>()) { 3078 CXXRecordDecl* RD = cast<CXXRecordDecl>(RT->getDecl()); 3079 if (RD->hasTrivialCopyAssignment()) 3080 return true; 3081 3082 bool FoundAssign = false; 3083 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(OO_Equal); 3084 LookupResult Res(Self, DeclarationNameInfo(Name, KeyLoc), 3085 Sema::LookupOrdinaryName); 3086 if (Self.LookupQualifiedName(Res, RD)) { 3087 Res.suppressDiagnostics(); 3088 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end(); 3089 Op != OpEnd; ++Op) { 3090 if (isa<FunctionTemplateDecl>(*Op)) 3091 continue; 3092 3093 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op); 3094 if (Operator->isCopyAssignmentOperator()) { 3095 FoundAssign = true; 3096 const FunctionProtoType *CPT 3097 = Operator->getType()->getAs<FunctionProtoType>(); 3098 if (CPT->getExceptionSpecType() == EST_Delayed) 3099 return false; 3100 if (!CPT->isNothrow(Self.Context)) 3101 return false; 3102 } 3103 } 3104 } 3105 3106 return FoundAssign; 3107 } 3108 return false; 3109 case UTT_HasNothrowCopy: 3110 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3111 // If __has_trivial_copy (type) is true then the trait is true, else 3112 // if type is a cv class or union type with copy constructors that are 3113 // known not to throw an exception then the trait is true, else it is 3114 // false. 3115 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType()) 3116 return true; 3117 if (const RecordType *RT = T->getAs<RecordType>()) { 3118 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3119 if (RD->hasTrivialCopyConstructor()) 3120 return true; 3121 3122 bool FoundConstructor = false; 3123 unsigned FoundTQs; 3124 DeclContext::lookup_const_iterator Con, ConEnd; 3125 for (llvm::tie(Con, ConEnd) = Self.LookupConstructors(RD); 3126 Con != ConEnd; ++Con) { 3127 // A template constructor is never a copy constructor. 3128 // FIXME: However, it may actually be selected at the actual overload 3129 // resolution point. 3130 if (isa<FunctionTemplateDecl>(*Con)) 3131 continue; 3132 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3133 if (Constructor->isCopyConstructor(FoundTQs)) { 3134 FoundConstructor = true; 3135 const FunctionProtoType *CPT 3136 = Constructor->getType()->getAs<FunctionProtoType>(); 3137 if (CPT->getExceptionSpecType() == EST_Delayed) 3138 return false; 3139 // FIXME: check whether evaluating default arguments can throw. 3140 // For now, we'll be conservative and assume that they can throw. 3141 if (!CPT->isNothrow(Self.Context) || CPT->getNumArgs() > 1) 3142 return false; 3143 } 3144 } 3145 3146 return FoundConstructor; 3147 } 3148 return false; 3149 case UTT_HasNothrowConstructor: 3150 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3151 // If __has_trivial_constructor (type) is true then the trait is 3152 // true, else if type is a cv class or union type (or array 3153 // thereof) with a default constructor that is known not to 3154 // throw an exception then the trait is true, else it is false. 3155 if (T.isPODType(C) || T->isObjCLifetimeType()) 3156 return true; 3157 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>()) { 3158 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 3159 if (RD->hasTrivialDefaultConstructor()) 3160 return true; 3161 3162 DeclContext::lookup_const_iterator Con, ConEnd; 3163 for (llvm::tie(Con, ConEnd) = Self.LookupConstructors(RD); 3164 Con != ConEnd; ++Con) { 3165 // FIXME: In C++0x, a constructor template can be a default constructor. 3166 if (isa<FunctionTemplateDecl>(*Con)) 3167 continue; 3168 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 3169 if (Constructor->isDefaultConstructor()) { 3170 const FunctionProtoType *CPT 3171 = Constructor->getType()->getAs<FunctionProtoType>(); 3172 if (CPT->getExceptionSpecType() == EST_Delayed) 3173 return false; 3174 // TODO: check whether evaluating default arguments can throw. 3175 // For now, we'll be conservative and assume that they can throw. 3176 return CPT->isNothrow(Self.Context) && CPT->getNumArgs() == 0; 3177 } 3178 } 3179 } 3180 return false; 3181 case UTT_HasVirtualDestructor: 3182 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html: 3183 // If type is a class type with a virtual destructor ([class.dtor]) 3184 // then the trait is true, else it is false. 3185 if (const RecordType *Record = T->getAs<RecordType>()) { 3186 CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl()); 3187 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD)) 3188 return Destructor->isVirtual(); 3189 } 3190 return false; 3191 3192 // These type trait expressions are modeled on the specifications for the 3193 // Embarcadero C++0x type trait functions: 3194 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index 3195 case UTT_IsCompleteType: 3196 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_): 3197 // Returns True if and only if T is a complete type at the point of the 3198 // function call. 3199 return !T->isIncompleteType(); 3200 } 3201 llvm_unreachable("Type trait not covered by switch"); 3202} 3203 3204ExprResult Sema::BuildUnaryTypeTrait(UnaryTypeTrait UTT, 3205 SourceLocation KWLoc, 3206 TypeSourceInfo *TSInfo, 3207 SourceLocation RParen) { 3208 QualType T = TSInfo->getType(); 3209 if (!CheckUnaryTypeTraitTypeCompleteness(*this, UTT, KWLoc, T)) 3210 return ExprError(); 3211 3212 bool Value = false; 3213 if (!T->isDependentType()) 3214 Value = EvaluateUnaryTypeTrait(*this, UTT, KWLoc, T); 3215 3216 return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, UTT, TSInfo, Value, 3217 RParen, Context.BoolTy)); 3218} 3219 3220ExprResult Sema::ActOnBinaryTypeTrait(BinaryTypeTrait BTT, 3221 SourceLocation KWLoc, 3222 ParsedType LhsTy, 3223 ParsedType RhsTy, 3224 SourceLocation RParen) { 3225 TypeSourceInfo *LhsTSInfo; 3226 QualType LhsT = GetTypeFromParser(LhsTy, &LhsTSInfo); 3227 if (!LhsTSInfo) 3228 LhsTSInfo = Context.getTrivialTypeSourceInfo(LhsT); 3229 3230 TypeSourceInfo *RhsTSInfo; 3231 QualType RhsT = GetTypeFromParser(RhsTy, &RhsTSInfo); 3232 if (!RhsTSInfo) 3233 RhsTSInfo = Context.getTrivialTypeSourceInfo(RhsT); 3234 3235 return BuildBinaryTypeTrait(BTT, KWLoc, LhsTSInfo, RhsTSInfo, RParen); 3236} 3237 3238static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc, 3239 ArrayRef<TypeSourceInfo *> Args, 3240 SourceLocation RParenLoc) { 3241 switch (Kind) { 3242 case clang::TT_IsTriviallyConstructible: { 3243 // C++11 [meta.unary.prop]: 3244 // is_trivially_constructible is defined as: 3245 // 3246 // is_constructible<T, Args...>::value is true and the variable 3247 // definition for is_constructible, as defined below, is known to call no 3248 // operation that is not trivial. 3249 // 3250 // The predicate condition for a template specialization 3251 // is_constructible<T, Args...> shall be satisfied if and only if the 3252 // following variable definition would be well-formed for some invented 3253 // variable t: 3254 // 3255 // T t(create<Args>()...); 3256 if (Args.empty()) { 3257 S.Diag(KWLoc, diag::err_type_trait_arity) 3258 << 1 << 1 << 1 << (int)Args.size(); 3259 return false; 3260 } 3261 3262 bool SawVoid = false; 3263 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3264 if (Args[I]->getType()->isVoidType()) { 3265 SawVoid = true; 3266 continue; 3267 } 3268 3269 if (!Args[I]->getType()->isIncompleteType() && 3270 S.RequireCompleteType(KWLoc, Args[I]->getType(), 3271 diag::err_incomplete_type_used_in_type_trait_expr)) 3272 return false; 3273 } 3274 3275 // If any argument was 'void', of course it won't type-check. 3276 if (SawVoid) 3277 return false; 3278 3279 llvm::SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs; 3280 llvm::SmallVector<Expr *, 2> ArgExprs; 3281 ArgExprs.reserve(Args.size() - 1); 3282 for (unsigned I = 1, N = Args.size(); I != N; ++I) { 3283 QualType T = Args[I]->getType(); 3284 if (T->isObjectType() || T->isFunctionType()) 3285 T = S.Context.getRValueReferenceType(T); 3286 OpaqueArgExprs.push_back( 3287 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(), 3288 T.getNonLValueExprType(S.Context), 3289 Expr::getValueKindForType(T))); 3290 ArgExprs.push_back(&OpaqueArgExprs.back()); 3291 } 3292 3293 // Perform the initialization in an unevaluated context within a SFINAE 3294 // trap at translation unit scope. 3295 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated); 3296 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true); 3297 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); 3298 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0])); 3299 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc, 3300 RParenLoc)); 3301 InitializationSequence Init(S, To, InitKind, 3302 ArgExprs.begin(), ArgExprs.size()); 3303 if (Init.Failed()) 3304 return false; 3305 3306 ExprResult Result = Init.Perform(S, To, InitKind, 3307 MultiExprArg(ArgExprs.data(), 3308 ArgExprs.size())); 3309 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3310 return false; 3311 3312 // The initialization succeeded; not make sure there are no non-trivial 3313 // calls. 3314 return !Result.get()->hasNonTrivialCall(S.Context); 3315 } 3316 } 3317 3318 return false; 3319} 3320 3321ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3322 ArrayRef<TypeSourceInfo *> Args, 3323 SourceLocation RParenLoc) { 3324 bool Dependent = false; 3325 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3326 if (Args[I]->getType()->isDependentType()) { 3327 Dependent = true; 3328 break; 3329 } 3330 } 3331 3332 bool Value = false; 3333 if (!Dependent) 3334 Value = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc); 3335 3336 return TypeTraitExpr::Create(Context, Context.BoolTy, KWLoc, Kind, 3337 Args, RParenLoc, Value); 3338} 3339 3340ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 3341 ArrayRef<ParsedType> Args, 3342 SourceLocation RParenLoc) { 3343 llvm::SmallVector<TypeSourceInfo *, 4> ConvertedArgs; 3344 ConvertedArgs.reserve(Args.size()); 3345 3346 for (unsigned I = 0, N = Args.size(); I != N; ++I) { 3347 TypeSourceInfo *TInfo; 3348 QualType T = GetTypeFromParser(Args[I], &TInfo); 3349 if (!TInfo) 3350 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc); 3351 3352 ConvertedArgs.push_back(TInfo); 3353 } 3354 3355 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc); 3356} 3357 3358static bool EvaluateBinaryTypeTrait(Sema &Self, BinaryTypeTrait BTT, 3359 QualType LhsT, QualType RhsT, 3360 SourceLocation KeyLoc) { 3361 assert(!LhsT->isDependentType() && !RhsT->isDependentType() && 3362 "Cannot evaluate traits of dependent types"); 3363 3364 switch(BTT) { 3365 case BTT_IsBaseOf: { 3366 // C++0x [meta.rel]p2 3367 // Base is a base class of Derived without regard to cv-qualifiers or 3368 // Base and Derived are not unions and name the same class type without 3369 // regard to cv-qualifiers. 3370 3371 const RecordType *lhsRecord = LhsT->getAs<RecordType>(); 3372 if (!lhsRecord) return false; 3373 3374 const RecordType *rhsRecord = RhsT->getAs<RecordType>(); 3375 if (!rhsRecord) return false; 3376 3377 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT) 3378 == (lhsRecord == rhsRecord)); 3379 3380 if (lhsRecord == rhsRecord) 3381 return !lhsRecord->getDecl()->isUnion(); 3382 3383 // C++0x [meta.rel]p2: 3384 // If Base and Derived are class types and are different types 3385 // (ignoring possible cv-qualifiers) then Derived shall be a 3386 // complete type. 3387 if (Self.RequireCompleteType(KeyLoc, RhsT, 3388 diag::err_incomplete_type_used_in_type_trait_expr)) 3389 return false; 3390 3391 return cast<CXXRecordDecl>(rhsRecord->getDecl()) 3392 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl())); 3393 } 3394 case BTT_IsSame: 3395 return Self.Context.hasSameType(LhsT, RhsT); 3396 case BTT_TypeCompatible: 3397 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(), 3398 RhsT.getUnqualifiedType()); 3399 case BTT_IsConvertible: 3400 case BTT_IsConvertibleTo: { 3401 // C++0x [meta.rel]p4: 3402 // Given the following function prototype: 3403 // 3404 // template <class T> 3405 // typename add_rvalue_reference<T>::type create(); 3406 // 3407 // the predicate condition for a template specialization 3408 // is_convertible<From, To> shall be satisfied if and only if 3409 // the return expression in the following code would be 3410 // well-formed, including any implicit conversions to the return 3411 // type of the function: 3412 // 3413 // To test() { 3414 // return create<From>(); 3415 // } 3416 // 3417 // Access checking is performed as if in a context unrelated to To and 3418 // From. Only the validity of the immediate context of the expression 3419 // of the return-statement (including conversions to the return type) 3420 // is considered. 3421 // 3422 // We model the initialization as a copy-initialization of a temporary 3423 // of the appropriate type, which for this expression is identical to the 3424 // return statement (since NRVO doesn't apply). 3425 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3426 LhsT = Self.Context.getRValueReferenceType(LhsT); 3427 3428 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT)); 3429 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3430 Expr::getValueKindForType(LhsT)); 3431 Expr *FromPtr = &From; 3432 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc, 3433 SourceLocation())); 3434 3435 // Perform the initialization in an unevaluated context within a SFINAE 3436 // trap at translation unit scope. 3437 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3438 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3439 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3440 InitializationSequence Init(Self, To, Kind, &FromPtr, 1); 3441 if (Init.Failed()) 3442 return false; 3443 3444 ExprResult Result = Init.Perform(Self, To, Kind, MultiExprArg(&FromPtr, 1)); 3445 return !Result.isInvalid() && !SFINAE.hasErrorOccurred(); 3446 } 3447 3448 case BTT_IsTriviallyAssignable: { 3449 // C++11 [meta.unary.prop]p3: 3450 // is_trivially_assignable is defined as: 3451 // is_assignable<T, U>::value is true and the assignment, as defined by 3452 // is_assignable, is known to call no operation that is not trivial 3453 // 3454 // is_assignable is defined as: 3455 // The expression declval<T>() = declval<U>() is well-formed when 3456 // treated as an unevaluated operand (Clause 5). 3457 // 3458 // For both, T and U shall be complete types, (possibly cv-qualified) 3459 // void, or arrays of unknown bound. 3460 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() && 3461 Self.RequireCompleteType(KeyLoc, LhsT, 3462 diag::err_incomplete_type_used_in_type_trait_expr)) 3463 return false; 3464 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() && 3465 Self.RequireCompleteType(KeyLoc, RhsT, 3466 diag::err_incomplete_type_used_in_type_trait_expr)) 3467 return false; 3468 3469 // cv void is never assignable. 3470 if (LhsT->isVoidType() || RhsT->isVoidType()) 3471 return false; 3472 3473 // Build expressions that emulate the effect of declval<T>() and 3474 // declval<U>(). 3475 if (LhsT->isObjectType() || LhsT->isFunctionType()) 3476 LhsT = Self.Context.getRValueReferenceType(LhsT); 3477 if (RhsT->isObjectType() || RhsT->isFunctionType()) 3478 RhsT = Self.Context.getRValueReferenceType(RhsT); 3479 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context), 3480 Expr::getValueKindForType(LhsT)); 3481 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context), 3482 Expr::getValueKindForType(RhsT)); 3483 3484 // Attempt the assignment in an unevaluated context within a SFINAE 3485 // trap at translation unit scope. 3486 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated); 3487 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true); 3488 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl()); 3489 ExprResult Result = Self.BuildBinOp(/*S=*/0, KeyLoc, BO_Assign, &Lhs, &Rhs); 3490 if (Result.isInvalid() || SFINAE.hasErrorOccurred()) 3491 return false; 3492 3493 return !Result.get()->hasNonTrivialCall(Self.Context); 3494 } 3495 } 3496 llvm_unreachable("Unknown type trait or not implemented"); 3497} 3498 3499ExprResult Sema::BuildBinaryTypeTrait(BinaryTypeTrait BTT, 3500 SourceLocation KWLoc, 3501 TypeSourceInfo *LhsTSInfo, 3502 TypeSourceInfo *RhsTSInfo, 3503 SourceLocation RParen) { 3504 QualType LhsT = LhsTSInfo->getType(); 3505 QualType RhsT = RhsTSInfo->getType(); 3506 3507 if (BTT == BTT_TypeCompatible) { 3508 if (getLangOpts().CPlusPlus) { 3509 Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus) 3510 << SourceRange(KWLoc, RParen); 3511 return ExprError(); 3512 } 3513 } 3514 3515 bool Value = false; 3516 if (!LhsT->isDependentType() && !RhsT->isDependentType()) 3517 Value = EvaluateBinaryTypeTrait(*this, BTT, LhsT, RhsT, KWLoc); 3518 3519 // Select trait result type. 3520 QualType ResultType; 3521 switch (BTT) { 3522 case BTT_IsBaseOf: ResultType = Context.BoolTy; break; 3523 case BTT_IsConvertible: ResultType = Context.BoolTy; break; 3524 case BTT_IsSame: ResultType = Context.BoolTy; break; 3525 case BTT_TypeCompatible: ResultType = Context.IntTy; break; 3526 case BTT_IsConvertibleTo: ResultType = Context.BoolTy; break; 3527 case BTT_IsTriviallyAssignable: ResultType = Context.BoolTy; 3528 } 3529 3530 return Owned(new (Context) BinaryTypeTraitExpr(KWLoc, BTT, LhsTSInfo, 3531 RhsTSInfo, Value, RParen, 3532 ResultType)); 3533} 3534 3535ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT, 3536 SourceLocation KWLoc, 3537 ParsedType Ty, 3538 Expr* DimExpr, 3539 SourceLocation RParen) { 3540 TypeSourceInfo *TSInfo; 3541 QualType T = GetTypeFromParser(Ty, &TSInfo); 3542 if (!TSInfo) 3543 TSInfo = Context.getTrivialTypeSourceInfo(T); 3544 3545 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen); 3546} 3547 3548static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT, 3549 QualType T, Expr *DimExpr, 3550 SourceLocation KeyLoc) { 3551 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type"); 3552 3553 switch(ATT) { 3554 case ATT_ArrayRank: 3555 if (T->isArrayType()) { 3556 unsigned Dim = 0; 3557 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3558 ++Dim; 3559 T = AT->getElementType(); 3560 } 3561 return Dim; 3562 } 3563 return 0; 3564 3565 case ATT_ArrayExtent: { 3566 llvm::APSInt Value; 3567 uint64_t Dim; 3568 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value, 3569 Self.PDiag(diag::err_dimension_expr_not_constant_integer), 3570 false).isInvalid()) 3571 return 0; 3572 if (Value.isSigned() && Value.isNegative()) { 3573 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer) 3574 << DimExpr->getSourceRange(); 3575 return 0; 3576 } 3577 Dim = Value.getLimitedValue(); 3578 3579 if (T->isArrayType()) { 3580 unsigned D = 0; 3581 bool Matched = false; 3582 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) { 3583 if (Dim == D) { 3584 Matched = true; 3585 break; 3586 } 3587 ++D; 3588 T = AT->getElementType(); 3589 } 3590 3591 if (Matched && T->isArrayType()) { 3592 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T)) 3593 return CAT->getSize().getLimitedValue(); 3594 } 3595 } 3596 return 0; 3597 } 3598 } 3599 llvm_unreachable("Unknown type trait or not implemented"); 3600} 3601 3602ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT, 3603 SourceLocation KWLoc, 3604 TypeSourceInfo *TSInfo, 3605 Expr* DimExpr, 3606 SourceLocation RParen) { 3607 QualType T = TSInfo->getType(); 3608 3609 // FIXME: This should likely be tracked as an APInt to remove any host 3610 // assumptions about the width of size_t on the target. 3611 uint64_t Value = 0; 3612 if (!T->isDependentType()) 3613 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc); 3614 3615 // While the specification for these traits from the Embarcadero C++ 3616 // compiler's documentation says the return type is 'unsigned int', Clang 3617 // returns 'size_t'. On Windows, the primary platform for the Embarcadero 3618 // compiler, there is no difference. On several other platforms this is an 3619 // important distinction. 3620 return Owned(new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, 3621 DimExpr, RParen, 3622 Context.getSizeType())); 3623} 3624 3625ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET, 3626 SourceLocation KWLoc, 3627 Expr *Queried, 3628 SourceLocation RParen) { 3629 // If error parsing the expression, ignore. 3630 if (!Queried) 3631 return ExprError(); 3632 3633 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen); 3634 3635 return move(Result); 3636} 3637 3638static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) { 3639 switch (ET) { 3640 case ET_IsLValueExpr: return E->isLValue(); 3641 case ET_IsRValueExpr: return E->isRValue(); 3642 } 3643 llvm_unreachable("Expression trait not covered by switch"); 3644} 3645 3646ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET, 3647 SourceLocation KWLoc, 3648 Expr *Queried, 3649 SourceLocation RParen) { 3650 if (Queried->isTypeDependent()) { 3651 // Delay type-checking for type-dependent expressions. 3652 } else if (Queried->getType()->isPlaceholderType()) { 3653 ExprResult PE = CheckPlaceholderExpr(Queried); 3654 if (PE.isInvalid()) return ExprError(); 3655 return BuildExpressionTrait(ET, KWLoc, PE.take(), RParen); 3656 } 3657 3658 bool Value = EvaluateExpressionTrait(ET, Queried); 3659 3660 return Owned(new (Context) ExpressionTraitExpr(KWLoc, ET, Queried, Value, 3661 RParen, Context.BoolTy)); 3662} 3663 3664QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS, 3665 ExprValueKind &VK, 3666 SourceLocation Loc, 3667 bool isIndirect) { 3668 assert(!LHS.get()->getType()->isPlaceholderType() && 3669 !RHS.get()->getType()->isPlaceholderType() && 3670 "placeholders should have been weeded out by now"); 3671 3672 // The LHS undergoes lvalue conversions if this is ->*. 3673 if (isIndirect) { 3674 LHS = DefaultLvalueConversion(LHS.take()); 3675 if (LHS.isInvalid()) return QualType(); 3676 } 3677 3678 // The RHS always undergoes lvalue conversions. 3679 RHS = DefaultLvalueConversion(RHS.take()); 3680 if (RHS.isInvalid()) return QualType(); 3681 3682 const char *OpSpelling = isIndirect ? "->*" : ".*"; 3683 // C++ 5.5p2 3684 // The binary operator .* [p3: ->*] binds its second operand, which shall 3685 // be of type "pointer to member of T" (where T is a completely-defined 3686 // class type) [...] 3687 QualType RHSType = RHS.get()->getType(); 3688 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>(); 3689 if (!MemPtr) { 3690 Diag(Loc, diag::err_bad_memptr_rhs) 3691 << OpSpelling << RHSType << RHS.get()->getSourceRange(); 3692 return QualType(); 3693 } 3694 3695 QualType Class(MemPtr->getClass(), 0); 3696 3697 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the 3698 // member pointer points must be completely-defined. However, there is no 3699 // reason for this semantic distinction, and the rule is not enforced by 3700 // other compilers. Therefore, we do not check this property, as it is 3701 // likely to be considered a defect. 3702 3703 // C++ 5.5p2 3704 // [...] to its first operand, which shall be of class T or of a class of 3705 // which T is an unambiguous and accessible base class. [p3: a pointer to 3706 // such a class] 3707 QualType LHSType = LHS.get()->getType(); 3708 if (isIndirect) { 3709 if (const PointerType *Ptr = LHSType->getAs<PointerType>()) 3710 LHSType = Ptr->getPointeeType(); 3711 else { 3712 Diag(Loc, diag::err_bad_memptr_lhs) 3713 << OpSpelling << 1 << LHSType 3714 << FixItHint::CreateReplacement(SourceRange(Loc), ".*"); 3715 return QualType(); 3716 } 3717 } 3718 3719 if (!Context.hasSameUnqualifiedType(Class, LHSType)) { 3720 // If we want to check the hierarchy, we need a complete type. 3721 if (RequireCompleteType(Loc, LHSType, PDiag(diag::err_bad_memptr_lhs) 3722 << OpSpelling << (int)isIndirect)) { 3723 return QualType(); 3724 } 3725 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 3726 /*DetectVirtual=*/false); 3727 // FIXME: Would it be useful to print full ambiguity paths, or is that 3728 // overkill? 3729 if (!IsDerivedFrom(LHSType, Class, Paths) || 3730 Paths.isAmbiguous(Context.getCanonicalType(Class))) { 3731 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling 3732 << (int)isIndirect << LHS.get()->getType(); 3733 return QualType(); 3734 } 3735 // Cast LHS to type of use. 3736 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class; 3737 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind(); 3738 3739 CXXCastPath BasePath; 3740 BuildBasePathArray(Paths, BasePath); 3741 LHS = ImpCastExprToType(LHS.take(), UseType, CK_DerivedToBase, VK, 3742 &BasePath); 3743 } 3744 3745 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) { 3746 // Diagnose use of pointer-to-member type which when used as 3747 // the functional cast in a pointer-to-member expression. 3748 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect; 3749 return QualType(); 3750 } 3751 3752 // C++ 5.5p2 3753 // The result is an object or a function of the type specified by the 3754 // second operand. 3755 // The cv qualifiers are the union of those in the pointer and the left side, 3756 // in accordance with 5.5p5 and 5.2.5. 3757 QualType Result = MemPtr->getPointeeType(); 3758 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers()); 3759 3760 // C++0x [expr.mptr.oper]p6: 3761 // In a .* expression whose object expression is an rvalue, the program is 3762 // ill-formed if the second operand is a pointer to member function with 3763 // ref-qualifier &. In a ->* expression or in a .* expression whose object 3764 // expression is an lvalue, the program is ill-formed if the second operand 3765 // is a pointer to member function with ref-qualifier &&. 3766 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) { 3767 switch (Proto->getRefQualifier()) { 3768 case RQ_None: 3769 // Do nothing 3770 break; 3771 3772 case RQ_LValue: 3773 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) 3774 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3775 << RHSType << 1 << LHS.get()->getSourceRange(); 3776 break; 3777 3778 case RQ_RValue: 3779 if (isIndirect || !LHS.get()->Classify(Context).isRValue()) 3780 Diag(Loc, diag::err_pointer_to_member_oper_value_classify) 3781 << RHSType << 0 << LHS.get()->getSourceRange(); 3782 break; 3783 } 3784 } 3785 3786 // C++ [expr.mptr.oper]p6: 3787 // The result of a .* expression whose second operand is a pointer 3788 // to a data member is of the same value category as its 3789 // first operand. The result of a .* expression whose second 3790 // operand is a pointer to a member function is a prvalue. The 3791 // result of an ->* expression is an lvalue if its second operand 3792 // is a pointer to data member and a prvalue otherwise. 3793 if (Result->isFunctionType()) { 3794 VK = VK_RValue; 3795 return Context.BoundMemberTy; 3796 } else if (isIndirect) { 3797 VK = VK_LValue; 3798 } else { 3799 VK = LHS.get()->getValueKind(); 3800 } 3801 3802 return Result; 3803} 3804 3805/// \brief Try to convert a type to another according to C++0x 5.16p3. 3806/// 3807/// This is part of the parameter validation for the ? operator. If either 3808/// value operand is a class type, the two operands are attempted to be 3809/// converted to each other. This function does the conversion in one direction. 3810/// It returns true if the program is ill-formed and has already been diagnosed 3811/// as such. 3812static bool TryClassUnification(Sema &Self, Expr *From, Expr *To, 3813 SourceLocation QuestionLoc, 3814 bool &HaveConversion, 3815 QualType &ToType) { 3816 HaveConversion = false; 3817 ToType = To->getType(); 3818 3819 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(), 3820 SourceLocation()); 3821 // C++0x 5.16p3 3822 // The process for determining whether an operand expression E1 of type T1 3823 // can be converted to match an operand expression E2 of type T2 is defined 3824 // as follows: 3825 // -- If E2 is an lvalue: 3826 bool ToIsLvalue = To->isLValue(); 3827 if (ToIsLvalue) { 3828 // E1 can be converted to match E2 if E1 can be implicitly converted to 3829 // type "lvalue reference to T2", subject to the constraint that in the 3830 // conversion the reference must bind directly to E1. 3831 QualType T = Self.Context.getLValueReferenceType(ToType); 3832 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3833 3834 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3835 if (InitSeq.isDirectReferenceBinding()) { 3836 ToType = T; 3837 HaveConversion = true; 3838 return false; 3839 } 3840 3841 if (InitSeq.isAmbiguous()) 3842 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3843 } 3844 3845 // -- If E2 is an rvalue, or if the conversion above cannot be done: 3846 // -- if E1 and E2 have class type, and the underlying class types are 3847 // the same or one is a base class of the other: 3848 QualType FTy = From->getType(); 3849 QualType TTy = To->getType(); 3850 const RecordType *FRec = FTy->getAs<RecordType>(); 3851 const RecordType *TRec = TTy->getAs<RecordType>(); 3852 bool FDerivedFromT = FRec && TRec && FRec != TRec && 3853 Self.IsDerivedFrom(FTy, TTy); 3854 if (FRec && TRec && 3855 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) { 3856 // E1 can be converted to match E2 if the class of T2 is the 3857 // same type as, or a base class of, the class of T1, and 3858 // [cv2 > cv1]. 3859 if (FRec == TRec || FDerivedFromT) { 3860 if (TTy.isAtLeastAsQualifiedAs(FTy)) { 3861 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3862 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3863 if (InitSeq) { 3864 HaveConversion = true; 3865 return false; 3866 } 3867 3868 if (InitSeq.isAmbiguous()) 3869 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3870 } 3871 } 3872 3873 return false; 3874 } 3875 3876 // -- Otherwise: E1 can be converted to match E2 if E1 can be 3877 // implicitly converted to the type that expression E2 would have 3878 // if E2 were converted to an rvalue (or the type it has, if E2 is 3879 // an rvalue). 3880 // 3881 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not 3882 // to the array-to-pointer or function-to-pointer conversions. 3883 if (!TTy->getAs<TagType>()) 3884 TTy = TTy.getUnqualifiedType(); 3885 3886 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy); 3887 InitializationSequence InitSeq(Self, Entity, Kind, &From, 1); 3888 HaveConversion = !InitSeq.Failed(); 3889 ToType = TTy; 3890 if (InitSeq.isAmbiguous()) 3891 return InitSeq.Diagnose(Self, Entity, Kind, &From, 1); 3892 3893 return false; 3894} 3895 3896/// \brief Try to find a common type for two according to C++0x 5.16p5. 3897/// 3898/// This is part of the parameter validation for the ? operator. If either 3899/// value operand is a class type, overload resolution is used to find a 3900/// conversion to a common type. 3901static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS, 3902 SourceLocation QuestionLoc) { 3903 Expr *Args[2] = { LHS.get(), RHS.get() }; 3904 OverloadCandidateSet CandidateSet(QuestionLoc); 3905 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args, 2, 3906 CandidateSet); 3907 3908 OverloadCandidateSet::iterator Best; 3909 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) { 3910 case OR_Success: { 3911 // We found a match. Perform the conversions on the arguments and move on. 3912 ExprResult LHSRes = 3913 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0], 3914 Best->Conversions[0], Sema::AA_Converting); 3915 if (LHSRes.isInvalid()) 3916 break; 3917 LHS = move(LHSRes); 3918 3919 ExprResult RHSRes = 3920 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1], 3921 Best->Conversions[1], Sema::AA_Converting); 3922 if (RHSRes.isInvalid()) 3923 break; 3924 RHS = move(RHSRes); 3925 if (Best->Function) 3926 Self.MarkFunctionReferenced(QuestionLoc, Best->Function); 3927 return false; 3928 } 3929 3930 case OR_No_Viable_Function: 3931 3932 // Emit a better diagnostic if one of the expressions is a null pointer 3933 // constant and the other is a pointer type. In this case, the user most 3934 // likely forgot to take the address of the other expression. 3935 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 3936 return true; 3937 3938 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3939 << LHS.get()->getType() << RHS.get()->getType() 3940 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3941 return true; 3942 3943 case OR_Ambiguous: 3944 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl) 3945 << LHS.get()->getType() << RHS.get()->getType() 3946 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 3947 // FIXME: Print the possible common types by printing the return types of 3948 // the viable candidates. 3949 break; 3950 3951 case OR_Deleted: 3952 llvm_unreachable("Conditional operator has only built-in overloads"); 3953 } 3954 return true; 3955} 3956 3957/// \brief Perform an "extended" implicit conversion as returned by 3958/// TryClassUnification. 3959static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) { 3960 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T); 3961 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(), 3962 SourceLocation()); 3963 Expr *Arg = E.take(); 3964 InitializationSequence InitSeq(Self, Entity, Kind, &Arg, 1); 3965 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, MultiExprArg(&Arg, 1)); 3966 if (Result.isInvalid()) 3967 return true; 3968 3969 E = Result; 3970 return false; 3971} 3972 3973/// \brief Check the operands of ?: under C++ semantics. 3974/// 3975/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y 3976/// extension. In this case, LHS == Cond. (But they're not aliases.) 3977QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, ExprResult &RHS, 3978 ExprValueKind &VK, ExprObjectKind &OK, 3979 SourceLocation QuestionLoc) { 3980 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++ 3981 // interface pointers. 3982 3983 // C++0x 5.16p1 3984 // The first expression is contextually converted to bool. 3985 if (!Cond.get()->isTypeDependent()) { 3986 ExprResult CondRes = CheckCXXBooleanCondition(Cond.take()); 3987 if (CondRes.isInvalid()) 3988 return QualType(); 3989 Cond = move(CondRes); 3990 } 3991 3992 // Assume r-value. 3993 VK = VK_RValue; 3994 OK = OK_Ordinary; 3995 3996 // Either of the arguments dependent? 3997 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent()) 3998 return Context.DependentTy; 3999 4000 // C++0x 5.16p2 4001 // If either the second or the third operand has type (cv) void, ... 4002 QualType LTy = LHS.get()->getType(); 4003 QualType RTy = RHS.get()->getType(); 4004 bool LVoid = LTy->isVoidType(); 4005 bool RVoid = RTy->isVoidType(); 4006 if (LVoid || RVoid) { 4007 // ... then the [l2r] conversions are performed on the second and third 4008 // operands ... 4009 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4010 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4011 if (LHS.isInvalid() || RHS.isInvalid()) 4012 return QualType(); 4013 LTy = LHS.get()->getType(); 4014 RTy = RHS.get()->getType(); 4015 4016 // ... and one of the following shall hold: 4017 // -- The second or the third operand (but not both) is a throw- 4018 // expression; the result is of the type of the other and is an rvalue. 4019 bool LThrow = isa<CXXThrowExpr>(LHS.get()); 4020 bool RThrow = isa<CXXThrowExpr>(RHS.get()); 4021 if (LThrow && !RThrow) 4022 return RTy; 4023 if (RThrow && !LThrow) 4024 return LTy; 4025 4026 // -- Both the second and third operands have type void; the result is of 4027 // type void and is an rvalue. 4028 if (LVoid && RVoid) 4029 return Context.VoidTy; 4030 4031 // Neither holds, error. 4032 Diag(QuestionLoc, diag::err_conditional_void_nonvoid) 4033 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1) 4034 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4035 return QualType(); 4036 } 4037 4038 // Neither is void. 4039 4040 // C++0x 5.16p3 4041 // Otherwise, if the second and third operand have different types, and 4042 // either has (cv) class type, and attempt is made to convert each of those 4043 // operands to the other. 4044 if (!Context.hasSameType(LTy, RTy) && 4045 (LTy->isRecordType() || RTy->isRecordType())) { 4046 ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft; 4047 // These return true if a single direction is already ambiguous. 4048 QualType L2RType, R2LType; 4049 bool HaveL2R, HaveR2L; 4050 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType)) 4051 return QualType(); 4052 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType)) 4053 return QualType(); 4054 4055 // If both can be converted, [...] the program is ill-formed. 4056 if (HaveL2R && HaveR2L) { 4057 Diag(QuestionLoc, diag::err_conditional_ambiguous) 4058 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4059 return QualType(); 4060 } 4061 4062 // If exactly one conversion is possible, that conversion is applied to 4063 // the chosen operand and the converted operands are used in place of the 4064 // original operands for the remainder of this section. 4065 if (HaveL2R) { 4066 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid()) 4067 return QualType(); 4068 LTy = LHS.get()->getType(); 4069 } else if (HaveR2L) { 4070 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid()) 4071 return QualType(); 4072 RTy = RHS.get()->getType(); 4073 } 4074 } 4075 4076 // C++0x 5.16p4 4077 // If the second and third operands are glvalues of the same value 4078 // category and have the same type, the result is of that type and 4079 // value category and it is a bit-field if the second or the third 4080 // operand is a bit-field, or if both are bit-fields. 4081 // We only extend this to bitfields, not to the crazy other kinds of 4082 // l-values. 4083 bool Same = Context.hasSameType(LTy, RTy); 4084 if (Same && 4085 LHS.get()->isGLValue() && 4086 LHS.get()->getValueKind() == RHS.get()->getValueKind() && 4087 LHS.get()->isOrdinaryOrBitFieldObject() && 4088 RHS.get()->isOrdinaryOrBitFieldObject()) { 4089 VK = LHS.get()->getValueKind(); 4090 if (LHS.get()->getObjectKind() == OK_BitField || 4091 RHS.get()->getObjectKind() == OK_BitField) 4092 OK = OK_BitField; 4093 return LTy; 4094 } 4095 4096 // C++0x 5.16p5 4097 // Otherwise, the result is an rvalue. If the second and third operands 4098 // do not have the same type, and either has (cv) class type, ... 4099 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) { 4100 // ... overload resolution is used to determine the conversions (if any) 4101 // to be applied to the operands. If the overload resolution fails, the 4102 // program is ill-formed. 4103 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc)) 4104 return QualType(); 4105 } 4106 4107 // C++0x 5.16p6 4108 // LValue-to-rvalue, array-to-pointer, and function-to-pointer standard 4109 // conversions are performed on the second and third operands. 4110 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 4111 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 4112 if (LHS.isInvalid() || RHS.isInvalid()) 4113 return QualType(); 4114 LTy = LHS.get()->getType(); 4115 RTy = RHS.get()->getType(); 4116 4117 // After those conversions, one of the following shall hold: 4118 // -- The second and third operands have the same type; the result 4119 // is of that type. If the operands have class type, the result 4120 // is a prvalue temporary of the result type, which is 4121 // copy-initialized from either the second operand or the third 4122 // operand depending on the value of the first operand. 4123 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) { 4124 if (LTy->isRecordType()) { 4125 // The operands have class type. Make a temporary copy. 4126 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy); 4127 ExprResult LHSCopy = PerformCopyInitialization(Entity, 4128 SourceLocation(), 4129 LHS); 4130 if (LHSCopy.isInvalid()) 4131 return QualType(); 4132 4133 ExprResult RHSCopy = PerformCopyInitialization(Entity, 4134 SourceLocation(), 4135 RHS); 4136 if (RHSCopy.isInvalid()) 4137 return QualType(); 4138 4139 LHS = LHSCopy; 4140 RHS = RHSCopy; 4141 } 4142 4143 return LTy; 4144 } 4145 4146 // Extension: conditional operator involving vector types. 4147 if (LTy->isVectorType() || RTy->isVectorType()) 4148 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4149 4150 // -- The second and third operands have arithmetic or enumeration type; 4151 // the usual arithmetic conversions are performed to bring them to a 4152 // common type, and the result is of that type. 4153 if (LTy->isArithmeticType() && RTy->isArithmeticType()) { 4154 UsualArithmeticConversions(LHS, RHS); 4155 if (LHS.isInvalid() || RHS.isInvalid()) 4156 return QualType(); 4157 return LHS.get()->getType(); 4158 } 4159 4160 // -- The second and third operands have pointer type, or one has pointer 4161 // type and the other is a null pointer constant; pointer conversions 4162 // and qualification conversions are performed to bring them to their 4163 // composite pointer type. The result is of the composite pointer type. 4164 // -- The second and third operands have pointer to member type, or one has 4165 // pointer to member type and the other is a null pointer constant; 4166 // pointer to member conversions and qualification conversions are 4167 // performed to bring them to a common type, whose cv-qualification 4168 // shall match the cv-qualification of either the second or the third 4169 // operand. The result is of the common type. 4170 bool NonStandardCompositeType = false; 4171 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS, 4172 isSFINAEContext()? 0 : &NonStandardCompositeType); 4173 if (!Composite.isNull()) { 4174 if (NonStandardCompositeType) 4175 Diag(QuestionLoc, 4176 diag::ext_typecheck_cond_incompatible_operands_nonstandard) 4177 << LTy << RTy << Composite 4178 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4179 4180 return Composite; 4181 } 4182 4183 // Similarly, attempt to find composite type of two objective-c pointers. 4184 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc); 4185 if (!Composite.isNull()) 4186 return Composite; 4187 4188 // Check if we are using a null with a non-pointer type. 4189 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4190 return QualType(); 4191 4192 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4193 << LHS.get()->getType() << RHS.get()->getType() 4194 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4195 return QualType(); 4196} 4197 4198/// \brief Find a merged pointer type and convert the two expressions to it. 4199/// 4200/// This finds the composite pointer type (or member pointer type) for @p E1 4201/// and @p E2 according to C++0x 5.9p2. It converts both expressions to this 4202/// type and returns it. 4203/// It does not emit diagnostics. 4204/// 4205/// \param Loc The location of the operator requiring these two expressions to 4206/// be converted to the composite pointer type. 4207/// 4208/// If \p NonStandardCompositeType is non-NULL, then we are permitted to find 4209/// a non-standard (but still sane) composite type to which both expressions 4210/// can be converted. When such a type is chosen, \c *NonStandardCompositeType 4211/// will be set true. 4212QualType Sema::FindCompositePointerType(SourceLocation Loc, 4213 Expr *&E1, Expr *&E2, 4214 bool *NonStandardCompositeType) { 4215 if (NonStandardCompositeType) 4216 *NonStandardCompositeType = false; 4217 4218 assert(getLangOpts().CPlusPlus && "This function assumes C++"); 4219 QualType T1 = E1->getType(), T2 = E2->getType(); 4220 4221 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() && 4222 !T2->isAnyPointerType() && !T2->isMemberPointerType()) 4223 return QualType(); 4224 4225 // C++0x 5.9p2 4226 // Pointer conversions and qualification conversions are performed on 4227 // pointer operands to bring them to their composite pointer type. If 4228 // one operand is a null pointer constant, the composite pointer type is 4229 // the type of the other operand. 4230 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4231 if (T2->isMemberPointerType()) 4232 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).take(); 4233 else 4234 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).take(); 4235 return T2; 4236 } 4237 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4238 if (T1->isMemberPointerType()) 4239 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).take(); 4240 else 4241 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).take(); 4242 return T1; 4243 } 4244 4245 // Now both have to be pointers or member pointers. 4246 if ((!T1->isPointerType() && !T1->isMemberPointerType()) || 4247 (!T2->isPointerType() && !T2->isMemberPointerType())) 4248 return QualType(); 4249 4250 // Otherwise, of one of the operands has type "pointer to cv1 void," then 4251 // the other has type "pointer to cv2 T" and the composite pointer type is 4252 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2. 4253 // Otherwise, the composite pointer type is a pointer type similar to the 4254 // type of one of the operands, with a cv-qualification signature that is 4255 // the union of the cv-qualification signatures of the operand types. 4256 // In practice, the first part here is redundant; it's subsumed by the second. 4257 // What we do here is, we build the two possible composite types, and try the 4258 // conversions in both directions. If only one works, or if the two composite 4259 // types are the same, we have succeeded. 4260 // FIXME: extended qualifiers? 4261 typedef SmallVector<unsigned, 4> QualifierVector; 4262 QualifierVector QualifierUnion; 4263 typedef SmallVector<std::pair<const Type *, const Type *>, 4> 4264 ContainingClassVector; 4265 ContainingClassVector MemberOfClass; 4266 QualType Composite1 = Context.getCanonicalType(T1), 4267 Composite2 = Context.getCanonicalType(T2); 4268 unsigned NeedConstBefore = 0; 4269 do { 4270 const PointerType *Ptr1, *Ptr2; 4271 if ((Ptr1 = Composite1->getAs<PointerType>()) && 4272 (Ptr2 = Composite2->getAs<PointerType>())) { 4273 Composite1 = Ptr1->getPointeeType(); 4274 Composite2 = Ptr2->getPointeeType(); 4275 4276 // If we're allowed to create a non-standard composite type, keep track 4277 // of where we need to fill in additional 'const' qualifiers. 4278 if (NonStandardCompositeType && 4279 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4280 NeedConstBefore = QualifierUnion.size(); 4281 4282 QualifierUnion.push_back( 4283 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4284 MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0)); 4285 continue; 4286 } 4287 4288 const MemberPointerType *MemPtr1, *MemPtr2; 4289 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) && 4290 (MemPtr2 = Composite2->getAs<MemberPointerType>())) { 4291 Composite1 = MemPtr1->getPointeeType(); 4292 Composite2 = MemPtr2->getPointeeType(); 4293 4294 // If we're allowed to create a non-standard composite type, keep track 4295 // of where we need to fill in additional 'const' qualifiers. 4296 if (NonStandardCompositeType && 4297 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers()) 4298 NeedConstBefore = QualifierUnion.size(); 4299 4300 QualifierUnion.push_back( 4301 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers()); 4302 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(), 4303 MemPtr2->getClass())); 4304 continue; 4305 } 4306 4307 // FIXME: block pointer types? 4308 4309 // Cannot unwrap any more types. 4310 break; 4311 } while (true); 4312 4313 if (NeedConstBefore && NonStandardCompositeType) { 4314 // Extension: Add 'const' to qualifiers that come before the first qualifier 4315 // mismatch, so that our (non-standard!) composite type meets the 4316 // requirements of C++ [conv.qual]p4 bullet 3. 4317 for (unsigned I = 0; I != NeedConstBefore; ++I) { 4318 if ((QualifierUnion[I] & Qualifiers::Const) == 0) { 4319 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const; 4320 *NonStandardCompositeType = true; 4321 } 4322 } 4323 } 4324 4325 // Rewrap the composites as pointers or member pointers with the union CVRs. 4326 ContainingClassVector::reverse_iterator MOC 4327 = MemberOfClass.rbegin(); 4328 for (QualifierVector::reverse_iterator 4329 I = QualifierUnion.rbegin(), 4330 E = QualifierUnion.rend(); 4331 I != E; (void)++I, ++MOC) { 4332 Qualifiers Quals = Qualifiers::fromCVRMask(*I); 4333 if (MOC->first && MOC->second) { 4334 // Rebuild member pointer type 4335 Composite1 = Context.getMemberPointerType( 4336 Context.getQualifiedType(Composite1, Quals), 4337 MOC->first); 4338 Composite2 = Context.getMemberPointerType( 4339 Context.getQualifiedType(Composite2, Quals), 4340 MOC->second); 4341 } else { 4342 // Rebuild pointer type 4343 Composite1 4344 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals)); 4345 Composite2 4346 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals)); 4347 } 4348 } 4349 4350 // Try to convert to the first composite pointer type. 4351 InitializedEntity Entity1 4352 = InitializedEntity::InitializeTemporary(Composite1); 4353 InitializationKind Kind 4354 = InitializationKind::CreateCopy(Loc, SourceLocation()); 4355 InitializationSequence E1ToC1(*this, Entity1, Kind, &E1, 1); 4356 InitializationSequence E2ToC1(*this, Entity1, Kind, &E2, 1); 4357 4358 if (E1ToC1 && E2ToC1) { 4359 // Conversion to Composite1 is viable. 4360 if (!Context.hasSameType(Composite1, Composite2)) { 4361 // Composite2 is a different type from Composite1. Check whether 4362 // Composite2 is also viable. 4363 InitializedEntity Entity2 4364 = InitializedEntity::InitializeTemporary(Composite2); 4365 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4366 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4367 if (E1ToC2 && E2ToC2) { 4368 // Both Composite1 and Composite2 are viable and are different; 4369 // this is an ambiguity. 4370 return QualType(); 4371 } 4372 } 4373 4374 // Convert E1 to Composite1 4375 ExprResult E1Result 4376 = E1ToC1.Perform(*this, Entity1, Kind, MultiExprArg(*this,&E1,1)); 4377 if (E1Result.isInvalid()) 4378 return QualType(); 4379 E1 = E1Result.takeAs<Expr>(); 4380 4381 // Convert E2 to Composite1 4382 ExprResult E2Result 4383 = E2ToC1.Perform(*this, Entity1, Kind, MultiExprArg(*this,&E2,1)); 4384 if (E2Result.isInvalid()) 4385 return QualType(); 4386 E2 = E2Result.takeAs<Expr>(); 4387 4388 return Composite1; 4389 } 4390 4391 // Check whether Composite2 is viable. 4392 InitializedEntity Entity2 4393 = InitializedEntity::InitializeTemporary(Composite2); 4394 InitializationSequence E1ToC2(*this, Entity2, Kind, &E1, 1); 4395 InitializationSequence E2ToC2(*this, Entity2, Kind, &E2, 1); 4396 if (!E1ToC2 || !E2ToC2) 4397 return QualType(); 4398 4399 // Convert E1 to Composite2 4400 ExprResult E1Result 4401 = E1ToC2.Perform(*this, Entity2, Kind, MultiExprArg(*this, &E1, 1)); 4402 if (E1Result.isInvalid()) 4403 return QualType(); 4404 E1 = E1Result.takeAs<Expr>(); 4405 4406 // Convert E2 to Composite2 4407 ExprResult E2Result 4408 = E2ToC2.Perform(*this, Entity2, Kind, MultiExprArg(*this, &E2, 1)); 4409 if (E2Result.isInvalid()) 4410 return QualType(); 4411 E2 = E2Result.takeAs<Expr>(); 4412 4413 return Composite2; 4414} 4415 4416ExprResult Sema::MaybeBindToTemporary(Expr *E) { 4417 if (!E) 4418 return ExprError(); 4419 4420 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?"); 4421 4422 // If the result is a glvalue, we shouldn't bind it. 4423 if (!E->isRValue()) 4424 return Owned(E); 4425 4426 // In ARC, calls that return a retainable type can return retained, 4427 // in which case we have to insert a consuming cast. 4428 if (getLangOpts().ObjCAutoRefCount && 4429 E->getType()->isObjCRetainableType()) { 4430 4431 bool ReturnsRetained; 4432 4433 // For actual calls, we compute this by examining the type of the 4434 // called value. 4435 if (CallExpr *Call = dyn_cast<CallExpr>(E)) { 4436 Expr *Callee = Call->getCallee()->IgnoreParens(); 4437 QualType T = Callee->getType(); 4438 4439 if (T == Context.BoundMemberTy) { 4440 // Handle pointer-to-members. 4441 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee)) 4442 T = BinOp->getRHS()->getType(); 4443 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee)) 4444 T = Mem->getMemberDecl()->getType(); 4445 } 4446 4447 if (const PointerType *Ptr = T->getAs<PointerType>()) 4448 T = Ptr->getPointeeType(); 4449 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>()) 4450 T = Ptr->getPointeeType(); 4451 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>()) 4452 T = MemPtr->getPointeeType(); 4453 4454 const FunctionType *FTy = T->getAs<FunctionType>(); 4455 assert(FTy && "call to value not of function type?"); 4456 ReturnsRetained = FTy->getExtInfo().getProducesResult(); 4457 4458 // ActOnStmtExpr arranges things so that StmtExprs of retainable 4459 // type always produce a +1 object. 4460 } else if (isa<StmtExpr>(E)) { 4461 ReturnsRetained = true; 4462 4463 // We hit this case with the lambda conversion-to-block optimization; 4464 // we don't want any extra casts here. 4465 } else if (isa<CastExpr>(E) && 4466 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) { 4467 return Owned(E); 4468 4469 // For message sends and property references, we try to find an 4470 // actual method. FIXME: we should infer retention by selector in 4471 // cases where we don't have an actual method. 4472 } else { 4473 ObjCMethodDecl *D = 0; 4474 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) { 4475 D = Send->getMethodDecl(); 4476 } else if (ObjCNumericLiteral *NumLit = dyn_cast<ObjCNumericLiteral>(E)) { 4477 D = NumLit->getObjCNumericLiteralMethod(); 4478 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) { 4479 D = ArrayLit->getArrayWithObjectsMethod(); 4480 } else if (ObjCDictionaryLiteral *DictLit 4481 = dyn_cast<ObjCDictionaryLiteral>(E)) { 4482 D = DictLit->getDictWithObjectsMethod(); 4483 } 4484 4485 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>()); 4486 4487 // Don't do reclaims on performSelector calls; despite their 4488 // return type, the invoked method doesn't necessarily actually 4489 // return an object. 4490 if (!ReturnsRetained && 4491 D && D->getMethodFamily() == OMF_performSelector) 4492 return Owned(E); 4493 } 4494 4495 // Don't reclaim an object of Class type. 4496 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType()) 4497 return Owned(E); 4498 4499 ExprNeedsCleanups = true; 4500 4501 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject 4502 : CK_ARCReclaimReturnedObject); 4503 return Owned(ImplicitCastExpr::Create(Context, E->getType(), ck, E, 0, 4504 VK_RValue)); 4505 } 4506 4507 if (!getLangOpts().CPlusPlus) 4508 return Owned(E); 4509 4510 // Search for the base element type (cf. ASTContext::getBaseElementType) with 4511 // a fast path for the common case that the type is directly a RecordType. 4512 const Type *T = Context.getCanonicalType(E->getType().getTypePtr()); 4513 const RecordType *RT = 0; 4514 while (!RT) { 4515 switch (T->getTypeClass()) { 4516 case Type::Record: 4517 RT = cast<RecordType>(T); 4518 break; 4519 case Type::ConstantArray: 4520 case Type::IncompleteArray: 4521 case Type::VariableArray: 4522 case Type::DependentSizedArray: 4523 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 4524 break; 4525 default: 4526 return Owned(E); 4527 } 4528 } 4529 4530 // That should be enough to guarantee that this type is complete, if we're 4531 // not processing a decltype expression. 4532 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 4533 if (RD->isInvalidDecl() || RD->isDependentContext()) 4534 return Owned(E); 4535 4536 bool IsDecltype = ExprEvalContexts.back().IsDecltype; 4537 CXXDestructorDecl *Destructor = IsDecltype ? 0 : LookupDestructor(RD); 4538 4539 if (Destructor) { 4540 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4541 CheckDestructorAccess(E->getExprLoc(), Destructor, 4542 PDiag(diag::err_access_dtor_temp) 4543 << E->getType()); 4544 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 4545 4546 // If destructor is trivial, we can avoid the extra copy. 4547 if (Destructor->isTrivial()) 4548 return Owned(E); 4549 4550 // We need a cleanup, but we don't need to remember the temporary. 4551 ExprNeedsCleanups = true; 4552 } 4553 4554 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor); 4555 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E); 4556 4557 if (IsDecltype) 4558 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind); 4559 4560 return Owned(Bind); 4561} 4562 4563ExprResult 4564Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) { 4565 if (SubExpr.isInvalid()) 4566 return ExprError(); 4567 4568 return Owned(MaybeCreateExprWithCleanups(SubExpr.take())); 4569} 4570 4571Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) { 4572 assert(SubExpr && "sub expression can't be null!"); 4573 4574 CleanupVarDeclMarking(); 4575 4576 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects; 4577 assert(ExprCleanupObjects.size() >= FirstCleanup); 4578 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup); 4579 if (!ExprNeedsCleanups) 4580 return SubExpr; 4581 4582 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups 4583 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup, 4584 ExprCleanupObjects.size() - FirstCleanup); 4585 4586 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups); 4587 DiscardCleanupsInEvaluationContext(); 4588 4589 return E; 4590} 4591 4592Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) { 4593 assert(SubStmt && "sub statement can't be null!"); 4594 4595 CleanupVarDeclMarking(); 4596 4597 if (!ExprNeedsCleanups) 4598 return SubStmt; 4599 4600 // FIXME: In order to attach the temporaries, wrap the statement into 4601 // a StmtExpr; currently this is only used for asm statements. 4602 // This is hacky, either create a new CXXStmtWithTemporaries statement or 4603 // a new AsmStmtWithTemporaries. 4604 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, &SubStmt, 1, 4605 SourceLocation(), 4606 SourceLocation()); 4607 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), 4608 SourceLocation()); 4609 return MaybeCreateExprWithCleanups(E); 4610} 4611 4612/// Process the expression contained within a decltype. For such expressions, 4613/// certain semantic checks on temporaries are delayed until this point, and 4614/// are omitted for the 'topmost' call in the decltype expression. If the 4615/// topmost call bound a temporary, strip that temporary off the expression. 4616ExprResult Sema::ActOnDecltypeExpression(Expr *E) { 4617 ExpressionEvaluationContextRecord &Rec = ExprEvalContexts.back(); 4618 assert(Rec.IsDecltype && "not in a decltype expression"); 4619 4620 // C++11 [expr.call]p11: 4621 // If a function call is a prvalue of object type, 4622 // -- if the function call is either 4623 // -- the operand of a decltype-specifier, or 4624 // -- the right operand of a comma operator that is the operand of a 4625 // decltype-specifier, 4626 // a temporary object is not introduced for the prvalue. 4627 4628 // Recursively rebuild ParenExprs and comma expressions to strip out the 4629 // outermost CXXBindTemporaryExpr, if any. 4630 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 4631 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr()); 4632 if (SubExpr.isInvalid()) 4633 return ExprError(); 4634 if (SubExpr.get() == PE->getSubExpr()) 4635 return Owned(E); 4636 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.take()); 4637 } 4638 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 4639 if (BO->getOpcode() == BO_Comma) { 4640 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS()); 4641 if (RHS.isInvalid()) 4642 return ExprError(); 4643 if (RHS.get() == BO->getRHS()) 4644 return Owned(E); 4645 return Owned(new (Context) BinaryOperator(BO->getLHS(), RHS.take(), 4646 BO_Comma, BO->getType(), 4647 BO->getValueKind(), 4648 BO->getObjectKind(), 4649 BO->getOperatorLoc())); 4650 } 4651 } 4652 4653 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E); 4654 if (TopBind) 4655 E = TopBind->getSubExpr(); 4656 4657 // Disable the special decltype handling now. 4658 Rec.IsDecltype = false; 4659 4660 // Perform the semantic checks we delayed until this point. 4661 CallExpr *TopCall = dyn_cast<CallExpr>(E); 4662 for (unsigned I = 0, N = Rec.DelayedDecltypeCalls.size(); I != N; ++I) { 4663 CallExpr *Call = Rec.DelayedDecltypeCalls[I]; 4664 if (Call == TopCall) 4665 continue; 4666 4667 if (CheckCallReturnType(Call->getCallReturnType(), 4668 Call->getLocStart(), 4669 Call, Call->getDirectCallee())) 4670 return ExprError(); 4671 } 4672 4673 // Now all relevant types are complete, check the destructors are accessible 4674 // and non-deleted, and annotate them on the temporaries. 4675 for (unsigned I = 0, N = Rec.DelayedDecltypeBinds.size(); I != N; ++I) { 4676 CXXBindTemporaryExpr *Bind = Rec.DelayedDecltypeBinds[I]; 4677 if (Bind == TopBind) 4678 continue; 4679 4680 CXXTemporary *Temp = Bind->getTemporary(); 4681 4682 CXXRecordDecl *RD = 4683 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 4684 CXXDestructorDecl *Destructor = LookupDestructor(RD); 4685 Temp->setDestructor(Destructor); 4686 4687 MarkFunctionReferenced(E->getExprLoc(), Destructor); 4688 CheckDestructorAccess(E->getExprLoc(), Destructor, 4689 PDiag(diag::err_access_dtor_temp) 4690 << E->getType()); 4691 DiagnoseUseOfDecl(Destructor, E->getExprLoc()); 4692 4693 // We need a cleanup, but we don't need to remember the temporary. 4694 ExprNeedsCleanups = true; 4695 } 4696 4697 // Possibly strip off the top CXXBindTemporaryExpr. 4698 return Owned(E); 4699} 4700 4701ExprResult 4702Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc, 4703 tok::TokenKind OpKind, ParsedType &ObjectType, 4704 bool &MayBePseudoDestructor) { 4705 // Since this might be a postfix expression, get rid of ParenListExprs. 4706 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4707 if (Result.isInvalid()) return ExprError(); 4708 Base = Result.get(); 4709 4710 Result = CheckPlaceholderExpr(Base); 4711 if (Result.isInvalid()) return ExprError(); 4712 Base = Result.take(); 4713 4714 QualType BaseType = Base->getType(); 4715 MayBePseudoDestructor = false; 4716 if (BaseType->isDependentType()) { 4717 // If we have a pointer to a dependent type and are using the -> operator, 4718 // the object type is the type that the pointer points to. We might still 4719 // have enough information about that type to do something useful. 4720 if (OpKind == tok::arrow) 4721 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 4722 BaseType = Ptr->getPointeeType(); 4723 4724 ObjectType = ParsedType::make(BaseType); 4725 MayBePseudoDestructor = true; 4726 return Owned(Base); 4727 } 4728 4729 // C++ [over.match.oper]p8: 4730 // [...] When operator->returns, the operator-> is applied to the value 4731 // returned, with the original second operand. 4732 if (OpKind == tok::arrow) { 4733 // The set of types we've considered so far. 4734 llvm::SmallPtrSet<CanQualType,8> CTypes; 4735 SmallVector<SourceLocation, 8> Locations; 4736 CTypes.insert(Context.getCanonicalType(BaseType)); 4737 4738 while (BaseType->isRecordType()) { 4739 Result = BuildOverloadedArrowExpr(S, Base, OpLoc); 4740 if (Result.isInvalid()) 4741 return ExprError(); 4742 Base = Result.get(); 4743 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base)) 4744 Locations.push_back(OpCall->getDirectCallee()->getLocation()); 4745 BaseType = Base->getType(); 4746 CanQualType CBaseType = Context.getCanonicalType(BaseType); 4747 if (!CTypes.insert(CBaseType)) { 4748 Diag(OpLoc, diag::err_operator_arrow_circular); 4749 for (unsigned i = 0; i < Locations.size(); i++) 4750 Diag(Locations[i], diag::note_declared_at); 4751 return ExprError(); 4752 } 4753 } 4754 4755 if (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()) 4756 BaseType = BaseType->getPointeeType(); 4757 } 4758 4759 // Objective-C properties allow "." access on Objective-C pointer types, 4760 // so adjust the base type to the object type itself. 4761 if (BaseType->isObjCObjectPointerType()) 4762 BaseType = BaseType->getPointeeType(); 4763 4764 // C++ [basic.lookup.classref]p2: 4765 // [...] If the type of the object expression is of pointer to scalar 4766 // type, the unqualified-id is looked up in the context of the complete 4767 // postfix-expression. 4768 // 4769 // This also indicates that we could be parsing a pseudo-destructor-name. 4770 // Note that Objective-C class and object types can be pseudo-destructor 4771 // expressions or normal member (ivar or property) access expressions. 4772 if (BaseType->isObjCObjectOrInterfaceType()) { 4773 MayBePseudoDestructor = true; 4774 } else if (!BaseType->isRecordType()) { 4775 ObjectType = ParsedType(); 4776 MayBePseudoDestructor = true; 4777 return Owned(Base); 4778 } 4779 4780 // The object type must be complete (or dependent). 4781 if (!BaseType->isDependentType() && 4782 RequireCompleteType(OpLoc, BaseType, 4783 PDiag(diag::err_incomplete_member_access))) 4784 return ExprError(); 4785 4786 // C++ [basic.lookup.classref]p2: 4787 // If the id-expression in a class member access (5.2.5) is an 4788 // unqualified-id, and the type of the object expression is of a class 4789 // type C (or of pointer to a class type C), the unqualified-id is looked 4790 // up in the scope of class C. [...] 4791 ObjectType = ParsedType::make(BaseType); 4792 return move(Base); 4793} 4794 4795ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc, 4796 Expr *MemExpr) { 4797 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc); 4798 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call) 4799 << isa<CXXPseudoDestructorExpr>(MemExpr) 4800 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()"); 4801 4802 return ActOnCallExpr(/*Scope*/ 0, 4803 MemExpr, 4804 /*LPLoc*/ ExpectedLParenLoc, 4805 MultiExprArg(), 4806 /*RPLoc*/ ExpectedLParenLoc); 4807} 4808 4809static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base, 4810 tok::TokenKind& OpKind, SourceLocation OpLoc) { 4811 if (Base->hasPlaceholderType()) { 4812 ExprResult result = S.CheckPlaceholderExpr(Base); 4813 if (result.isInvalid()) return true; 4814 Base = result.take(); 4815 } 4816 ObjectType = Base->getType(); 4817 4818 // C++ [expr.pseudo]p2: 4819 // The left-hand side of the dot operator shall be of scalar type. The 4820 // left-hand side of the arrow operator shall be of pointer to scalar type. 4821 // This scalar type is the object type. 4822 // Note that this is rather different from the normal handling for the 4823 // arrow operator. 4824 if (OpKind == tok::arrow) { 4825 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) { 4826 ObjectType = Ptr->getPointeeType(); 4827 } else if (!Base->isTypeDependent()) { 4828 // The user wrote "p->" when she probably meant "p."; fix it. 4829 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 4830 << ObjectType << true 4831 << FixItHint::CreateReplacement(OpLoc, "."); 4832 if (S.isSFINAEContext()) 4833 return true; 4834 4835 OpKind = tok::period; 4836 } 4837 } 4838 4839 return false; 4840} 4841 4842ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base, 4843 SourceLocation OpLoc, 4844 tok::TokenKind OpKind, 4845 const CXXScopeSpec &SS, 4846 TypeSourceInfo *ScopeTypeInfo, 4847 SourceLocation CCLoc, 4848 SourceLocation TildeLoc, 4849 PseudoDestructorTypeStorage Destructed, 4850 bool HasTrailingLParen) { 4851 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo(); 4852 4853 QualType ObjectType; 4854 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4855 return ExprError(); 4856 4857 if (!ObjectType->isDependentType() && !ObjectType->isScalarType()) { 4858 if (getLangOpts().MicrosoftMode && ObjectType->isVoidType()) 4859 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange(); 4860 else 4861 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 4862 << ObjectType << Base->getSourceRange(); 4863 return ExprError(); 4864 } 4865 4866 // C++ [expr.pseudo]p2: 4867 // [...] The cv-unqualified versions of the object type and of the type 4868 // designated by the pseudo-destructor-name shall be the same type. 4869 if (DestructedTypeInfo) { 4870 QualType DestructedType = DestructedTypeInfo->getType(); 4871 SourceLocation DestructedTypeStart 4872 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(); 4873 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) { 4874 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) { 4875 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch) 4876 << ObjectType << DestructedType << Base->getSourceRange() 4877 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 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 } else if (DestructedType.getObjCLifetime() != 4885 ObjectType.getObjCLifetime()) { 4886 4887 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) { 4888 // Okay: just pretend that the user provided the correctly-qualified 4889 // type. 4890 } else { 4891 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals) 4892 << ObjectType << DestructedType << Base->getSourceRange() 4893 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange(); 4894 } 4895 4896 // Recover by setting the destructed type to the object type. 4897 DestructedType = ObjectType; 4898 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType, 4899 DestructedTypeStart); 4900 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 4901 } 4902 } 4903 } 4904 4905 // C++ [expr.pseudo]p2: 4906 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the 4907 // form 4908 // 4909 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name 4910 // 4911 // shall designate the same scalar type. 4912 if (ScopeTypeInfo) { 4913 QualType ScopeType = ScopeTypeInfo->getType(); 4914 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() && 4915 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) { 4916 4917 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(), 4918 diag::err_pseudo_dtor_type_mismatch) 4919 << ObjectType << ScopeType << Base->getSourceRange() 4920 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange(); 4921 4922 ScopeType = QualType(); 4923 ScopeTypeInfo = 0; 4924 } 4925 } 4926 4927 Expr *Result 4928 = new (Context) CXXPseudoDestructorExpr(Context, Base, 4929 OpKind == tok::arrow, OpLoc, 4930 SS.getWithLocInContext(Context), 4931 ScopeTypeInfo, 4932 CCLoc, 4933 TildeLoc, 4934 Destructed); 4935 4936 if (HasTrailingLParen) 4937 return Owned(Result); 4938 4939 return DiagnoseDtorReference(Destructed.getLocation(), Result); 4940} 4941 4942ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 4943 SourceLocation OpLoc, 4944 tok::TokenKind OpKind, 4945 CXXScopeSpec &SS, 4946 UnqualifiedId &FirstTypeName, 4947 SourceLocation CCLoc, 4948 SourceLocation TildeLoc, 4949 UnqualifiedId &SecondTypeName, 4950 bool HasTrailingLParen) { 4951 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4952 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) && 4953 "Invalid first type name in pseudo-destructor"); 4954 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId || 4955 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) && 4956 "Invalid second type name in pseudo-destructor"); 4957 4958 QualType ObjectType; 4959 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 4960 return ExprError(); 4961 4962 // Compute the object type that we should use for name lookup purposes. Only 4963 // record types and dependent types matter. 4964 ParsedType ObjectTypePtrForLookup; 4965 if (!SS.isSet()) { 4966 if (ObjectType->isRecordType()) 4967 ObjectTypePtrForLookup = ParsedType::make(ObjectType); 4968 else if (ObjectType->isDependentType()) 4969 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy); 4970 } 4971 4972 // Convert the name of the type being destructed (following the ~) into a 4973 // type (with source-location information). 4974 QualType DestructedType; 4975 TypeSourceInfo *DestructedTypeInfo = 0; 4976 PseudoDestructorTypeStorage Destructed; 4977 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) { 4978 ParsedType T = getTypeName(*SecondTypeName.Identifier, 4979 SecondTypeName.StartLocation, 4980 S, &SS, true, false, ObjectTypePtrForLookup); 4981 if (!T && 4982 ((SS.isSet() && !computeDeclContext(SS, false)) || 4983 (!SS.isSet() && ObjectType->isDependentType()))) { 4984 // The name of the type being destroyed is a dependent name, and we 4985 // couldn't find anything useful in scope. Just store the identifier and 4986 // it's location, and we'll perform (qualified) name lookup again at 4987 // template instantiation time. 4988 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier, 4989 SecondTypeName.StartLocation); 4990 } else if (!T) { 4991 Diag(SecondTypeName.StartLocation, 4992 diag::err_pseudo_dtor_destructor_non_type) 4993 << SecondTypeName.Identifier << ObjectType; 4994 if (isSFINAEContext()) 4995 return ExprError(); 4996 4997 // Recover by assuming we had the right type all along. 4998 DestructedType = ObjectType; 4999 } else 5000 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo); 5001 } else { 5002 // Resolve the template-id to a type. 5003 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId; 5004 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5005 TemplateId->getTemplateArgs(), 5006 TemplateId->NumArgs); 5007 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5008 TemplateId->TemplateKWLoc, 5009 TemplateId->Template, 5010 TemplateId->TemplateNameLoc, 5011 TemplateId->LAngleLoc, 5012 TemplateArgsPtr, 5013 TemplateId->RAngleLoc); 5014 if (T.isInvalid() || !T.get()) { 5015 // Recover by assuming we had the right type all along. 5016 DestructedType = ObjectType; 5017 } else 5018 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo); 5019 } 5020 5021 // If we've performed some kind of recovery, (re-)build the type source 5022 // information. 5023 if (!DestructedType.isNull()) { 5024 if (!DestructedTypeInfo) 5025 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType, 5026 SecondTypeName.StartLocation); 5027 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo); 5028 } 5029 5030 // Convert the name of the scope type (the type prior to '::') into a type. 5031 TypeSourceInfo *ScopeTypeInfo = 0; 5032 QualType ScopeType; 5033 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId || 5034 FirstTypeName.Identifier) { 5035 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) { 5036 ParsedType T = getTypeName(*FirstTypeName.Identifier, 5037 FirstTypeName.StartLocation, 5038 S, &SS, true, false, ObjectTypePtrForLookup); 5039 if (!T) { 5040 Diag(FirstTypeName.StartLocation, 5041 diag::err_pseudo_dtor_destructor_non_type) 5042 << FirstTypeName.Identifier << ObjectType; 5043 5044 if (isSFINAEContext()) 5045 return ExprError(); 5046 5047 // Just drop this type. It's unnecessary anyway. 5048 ScopeType = QualType(); 5049 } else 5050 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo); 5051 } else { 5052 // Resolve the template-id to a type. 5053 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId; 5054 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5055 TemplateId->getTemplateArgs(), 5056 TemplateId->NumArgs); 5057 TypeResult T = ActOnTemplateIdType(TemplateId->SS, 5058 TemplateId->TemplateKWLoc, 5059 TemplateId->Template, 5060 TemplateId->TemplateNameLoc, 5061 TemplateId->LAngleLoc, 5062 TemplateArgsPtr, 5063 TemplateId->RAngleLoc); 5064 if (T.isInvalid() || !T.get()) { 5065 // Recover by dropping this type. 5066 ScopeType = QualType(); 5067 } else 5068 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo); 5069 } 5070 } 5071 5072 if (!ScopeType.isNull() && !ScopeTypeInfo) 5073 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType, 5074 FirstTypeName.StartLocation); 5075 5076 5077 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS, 5078 ScopeTypeInfo, CCLoc, TildeLoc, 5079 Destructed, HasTrailingLParen); 5080} 5081 5082ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base, 5083 SourceLocation OpLoc, 5084 tok::TokenKind OpKind, 5085 SourceLocation TildeLoc, 5086 const DeclSpec& DS, 5087 bool HasTrailingLParen) { 5088 QualType ObjectType; 5089 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc)) 5090 return ExprError(); 5091 5092 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 5093 5094 TypeLocBuilder TLB; 5095 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 5096 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 5097 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T); 5098 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo); 5099 5100 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(), 5101 0, SourceLocation(), TildeLoc, 5102 Destructed, HasTrailingLParen); 5103} 5104 5105ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl, 5106 CXXConversionDecl *Method, 5107 bool HadMultipleCandidates) { 5108 if (Method->getParent()->isLambda() && 5109 Method->getConversionType()->isBlockPointerType()) { 5110 // This is a lambda coversion to block pointer; check if the argument 5111 // is a LambdaExpr. 5112 Expr *SubE = E; 5113 CastExpr *CE = dyn_cast<CastExpr>(SubE); 5114 if (CE && CE->getCastKind() == CK_NoOp) 5115 SubE = CE->getSubExpr(); 5116 SubE = SubE->IgnoreParens(); 5117 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE)) 5118 SubE = BE->getSubExpr(); 5119 if (isa<LambdaExpr>(SubE)) { 5120 // For the conversion to block pointer on a lambda expression, we 5121 // construct a special BlockLiteral instead; this doesn't really make 5122 // a difference in ARC, but outside of ARC the resulting block literal 5123 // follows the normal lifetime rules for block literals instead of being 5124 // autoreleased. 5125 DiagnosticErrorTrap Trap(Diags); 5126 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(), 5127 E->getExprLoc(), 5128 Method, E); 5129 if (Exp.isInvalid()) 5130 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv); 5131 return Exp; 5132 } 5133 } 5134 5135 5136 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0, 5137 FoundDecl, Method); 5138 if (Exp.isInvalid()) 5139 return true; 5140 5141 MemberExpr *ME = 5142 new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method, 5143 SourceLocation(), Context.BoundMemberTy, 5144 VK_RValue, OK_Ordinary); 5145 if (HadMultipleCandidates) 5146 ME->setHadMultipleCandidates(true); 5147 5148 QualType ResultType = Method->getResultType(); 5149 ExprValueKind VK = Expr::getValueKindForType(ResultType); 5150 ResultType = ResultType.getNonLValueExprType(Context); 5151 5152 MarkFunctionReferenced(Exp.get()->getLocStart(), Method); 5153 CXXMemberCallExpr *CE = 5154 new (Context) CXXMemberCallExpr(Context, ME, 0, 0, ResultType, VK, 5155 Exp.get()->getLocEnd()); 5156 return CE; 5157} 5158 5159ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand, 5160 SourceLocation RParen) { 5161 return Owned(new (Context) CXXNoexceptExpr(Context.BoolTy, Operand, 5162 Operand->CanThrow(Context), 5163 KeyLoc, RParen)); 5164} 5165 5166ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation, 5167 Expr *Operand, SourceLocation RParen) { 5168 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen); 5169} 5170 5171/// Perform the conversions required for an expression used in a 5172/// context that ignores the result. 5173ExprResult Sema::IgnoredValueConversions(Expr *E) { 5174 if (E->hasPlaceholderType()) { 5175 ExprResult result = CheckPlaceholderExpr(E); 5176 if (result.isInvalid()) return Owned(E); 5177 E = result.take(); 5178 } 5179 5180 // C99 6.3.2.1: 5181 // [Except in specific positions,] an lvalue that does not have 5182 // array type is converted to the value stored in the 5183 // designated object (and is no longer an lvalue). 5184 if (E->isRValue()) { 5185 // In C, function designators (i.e. expressions of function type) 5186 // are r-values, but we still want to do function-to-pointer decay 5187 // on them. This is both technically correct and convenient for 5188 // some clients. 5189 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType()) 5190 return DefaultFunctionArrayConversion(E); 5191 5192 return Owned(E); 5193 } 5194 5195 // Otherwise, this rule does not apply in C++, at least not for the moment. 5196 if (getLangOpts().CPlusPlus) return Owned(E); 5197 5198 // GCC seems to also exclude expressions of incomplete enum type. 5199 if (const EnumType *T = E->getType()->getAs<EnumType>()) { 5200 if (!T->getDecl()->isComplete()) { 5201 // FIXME: stupid workaround for a codegen bug! 5202 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).take(); 5203 return Owned(E); 5204 } 5205 } 5206 5207 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 5208 if (Res.isInvalid()) 5209 return Owned(E); 5210 E = Res.take(); 5211 5212 if (!E->getType()->isVoidType()) 5213 RequireCompleteType(E->getExprLoc(), E->getType(), 5214 diag::err_incomplete_type); 5215 return Owned(E); 5216} 5217 5218ExprResult Sema::ActOnFinishFullExpr(Expr *FE) { 5219 ExprResult FullExpr = Owned(FE); 5220 5221 if (!FullExpr.get()) 5222 return ExprError(); 5223 5224 if (DiagnoseUnexpandedParameterPack(FullExpr.get())) 5225 return ExprError(); 5226 5227 // Top-level message sends default to 'id' when we're in a debugger. 5228 if (getLangOpts().DebuggerCastResultToId && 5229 FullExpr.get()->getType() == Context.UnknownAnyTy && 5230 isa<ObjCMessageExpr>(FullExpr.get())) { 5231 FullExpr = forceUnknownAnyToType(FullExpr.take(), Context.getObjCIdType()); 5232 if (FullExpr.isInvalid()) 5233 return ExprError(); 5234 } 5235 5236 FullExpr = CheckPlaceholderExpr(FullExpr.take()); 5237 if (FullExpr.isInvalid()) 5238 return ExprError(); 5239 5240 FullExpr = IgnoredValueConversions(FullExpr.take()); 5241 if (FullExpr.isInvalid()) 5242 return ExprError(); 5243 5244 CheckImplicitConversions(FullExpr.get(), FullExpr.get()->getExprLoc()); 5245 return MaybeCreateExprWithCleanups(FullExpr); 5246} 5247 5248StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) { 5249 if (!FullStmt) return StmtError(); 5250 5251 return MaybeCreateStmtWithCleanups(FullStmt); 5252} 5253 5254Sema::IfExistsResult 5255Sema::CheckMicrosoftIfExistsSymbol(Scope *S, 5256 CXXScopeSpec &SS, 5257 const DeclarationNameInfo &TargetNameInfo) { 5258 DeclarationName TargetName = TargetNameInfo.getName(); 5259 if (!TargetName) 5260 return IER_DoesNotExist; 5261 5262 // If the name itself is dependent, then the result is dependent. 5263 if (TargetName.isDependentName()) 5264 return IER_Dependent; 5265 5266 // Do the redeclaration lookup in the current scope. 5267 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName, 5268 Sema::NotForRedeclaration); 5269 LookupParsedName(R, S, &SS); 5270 R.suppressDiagnostics(); 5271 5272 switch (R.getResultKind()) { 5273 case LookupResult::Found: 5274 case LookupResult::FoundOverloaded: 5275 case LookupResult::FoundUnresolvedValue: 5276 case LookupResult::Ambiguous: 5277 return IER_Exists; 5278 5279 case LookupResult::NotFound: 5280 return IER_DoesNotExist; 5281 5282 case LookupResult::NotFoundInCurrentInstantiation: 5283 return IER_Dependent; 5284 } 5285 5286 llvm_unreachable("Invalid LookupResult Kind!"); 5287} 5288 5289Sema::IfExistsResult 5290Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc, 5291 bool IsIfExists, CXXScopeSpec &SS, 5292 UnqualifiedId &Name) { 5293 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name); 5294 5295 // Check for unexpanded parameter packs. 5296 SmallVector<UnexpandedParameterPack, 4> Unexpanded; 5297 collectUnexpandedParameterPacks(SS, Unexpanded); 5298 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded); 5299 if (!Unexpanded.empty()) { 5300 DiagnoseUnexpandedParameterPacks(KeywordLoc, 5301 IsIfExists? UPPC_IfExists 5302 : UPPC_IfNotExists, 5303 Unexpanded); 5304 return IER_Error; 5305 } 5306 5307 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo); 5308} 5309