1 //===--- SemaInit.cpp - Semantic Analysis for Initializers ----------------===// 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 initializers. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "clang/Sema/Designator.h" 15 #include "clang/Sema/Initialization.h" 16 #include "clang/Sema/Lookup.h" 17 #include "clang/Sema/SemaInternal.h" 18 #include "clang/Lex/Preprocessor.h" 19 #include "clang/AST/ASTContext.h" 20 #include "clang/AST/DeclObjC.h" 21 #include "clang/AST/ExprCXX.h" 22 #include "clang/AST/ExprObjC.h" 23 #include "clang/AST/TypeLoc.h" 24 #include "llvm/ADT/APInt.h" 25 #include "llvm/ADT/SmallString.h" 26 #include "llvm/Support/ErrorHandling.h" 27 #include "llvm/Support/raw_ostream.h" 28 #include <map> 29 using namespace clang; 30 31 //===----------------------------------------------------------------------===// 32 // Sema Initialization Checking 33 //===----------------------------------------------------------------------===// 34 35 static Expr *IsStringInit(Expr *Init, const ArrayType *AT, 36 ASTContext &Context) { 37 if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT)) 38 return 0; 39 40 // See if this is a string literal or @encode. 41 Init = Init->IgnoreParens(); 42 43 // Handle @encode, which is a narrow string. 44 if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType()) 45 return Init; 46 47 // Otherwise we can only handle string literals. 48 StringLiteral *SL = dyn_cast<StringLiteral>(Init); 49 if (SL == 0) return 0; 50 51 QualType ElemTy = Context.getCanonicalType(AT->getElementType()); 52 53 switch (SL->getKind()) { 54 case StringLiteral::Ascii: 55 case StringLiteral::UTF8: 56 // char array can be initialized with a narrow string. 57 // Only allow char x[] = "foo"; not char x[] = L"foo"; 58 return ElemTy->isCharType() ? Init : 0; 59 case StringLiteral::UTF16: 60 return ElemTy->isChar16Type() ? Init : 0; 61 case StringLiteral::UTF32: 62 return ElemTy->isChar32Type() ? Init : 0; 63 case StringLiteral::Wide: 64 // wchar_t array can be initialized with a wide string: C99 6.7.8p15 (with 65 // correction from DR343): "An array with element type compatible with a 66 // qualified or unqualified version of wchar_t may be initialized by a wide 67 // string literal, optionally enclosed in braces." 68 if (Context.typesAreCompatible(Context.getWCharType(), 69 ElemTy.getUnqualifiedType())) 70 return Init; 71 72 return 0; 73 } 74 75 llvm_unreachable("missed a StringLiteral kind?"); 76 } 77 78 static Expr *IsStringInit(Expr *init, QualType declType, ASTContext &Context) { 79 const ArrayType *arrayType = Context.getAsArrayType(declType); 80 if (!arrayType) return 0; 81 82 return IsStringInit(init, arrayType, Context); 83 } 84 85 static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT, 86 Sema &S) { 87 // Get the length of the string as parsed. 88 uint64_t StrLength = 89 cast<ConstantArrayType>(Str->getType())->getSize().getZExtValue(); 90 91 92 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 93 // C99 6.7.8p14. We have an array of character type with unknown size 94 // being initialized to a string literal. 95 llvm::APSInt ConstVal(32); 96 ConstVal = StrLength; 97 // Return a new array type (C99 6.7.8p22). 98 DeclT = S.Context.getConstantArrayType(IAT->getElementType(), 99 ConstVal, 100 ArrayType::Normal, 0); 101 return; 102 } 103 104 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 105 106 // We have an array of character type with known size. However, 107 // the size may be smaller or larger than the string we are initializing. 108 // FIXME: Avoid truncation for 64-bit length strings. 109 if (S.getLangOpts().CPlusPlus) { 110 if (StringLiteral *SL = dyn_cast<StringLiteral>(Str)) { 111 // For Pascal strings it's OK to strip off the terminating null character, 112 // so the example below is valid: 113 // 114 // unsigned char a[2] = "\pa"; 115 if (SL->isPascal()) 116 StrLength--; 117 } 118 119 // [dcl.init.string]p2 120 if (StrLength > CAT->getSize().getZExtValue()) 121 S.Diag(Str->getLocStart(), 122 diag::err_initializer_string_for_char_array_too_long) 123 << Str->getSourceRange(); 124 } else { 125 // C99 6.7.8p14. 126 if (StrLength-1 > CAT->getSize().getZExtValue()) 127 S.Diag(Str->getLocStart(), 128 diag::warn_initializer_string_for_char_array_too_long) 129 << Str->getSourceRange(); 130 } 131 132 // Set the type to the actual size that we are initializing. If we have 133 // something like: 134 // char x[1] = "foo"; 135 // then this will set the string literal's type to char[1]. 136 Str->setType(DeclT); 137 } 138 139 //===----------------------------------------------------------------------===// 140 // Semantic checking for initializer lists. 141 //===----------------------------------------------------------------------===// 142 143 /// @brief Semantic checking for initializer lists. 144 /// 145 /// The InitListChecker class contains a set of routines that each 146 /// handle the initialization of a certain kind of entity, e.g., 147 /// arrays, vectors, struct/union types, scalars, etc. The 148 /// InitListChecker itself performs a recursive walk of the subobject 149 /// structure of the type to be initialized, while stepping through 150 /// the initializer list one element at a time. The IList and Index 151 /// parameters to each of the Check* routines contain the active 152 /// (syntactic) initializer list and the index into that initializer 153 /// list that represents the current initializer. Each routine is 154 /// responsible for moving that Index forward as it consumes elements. 155 /// 156 /// Each Check* routine also has a StructuredList/StructuredIndex 157 /// arguments, which contains the current "structured" (semantic) 158 /// initializer list and the index into that initializer list where we 159 /// are copying initializers as we map them over to the semantic 160 /// list. Once we have completed our recursive walk of the subobject 161 /// structure, we will have constructed a full semantic initializer 162 /// list. 163 /// 164 /// C99 designators cause changes in the initializer list traversal, 165 /// because they make the initialization "jump" into a specific 166 /// subobject and then continue the initialization from that 167 /// point. CheckDesignatedInitializer() recursively steps into the 168 /// designated subobject and manages backing out the recursion to 169 /// initialize the subobjects after the one designated. 170 namespace { 171 class InitListChecker { 172 Sema &SemaRef; 173 bool hadError; 174 bool VerifyOnly; // no diagnostics, no structure building 175 bool AllowBraceElision; 176 llvm::DenseMap<InitListExpr *, InitListExpr *> SyntacticToSemantic; 177 InitListExpr *FullyStructuredList; 178 179 void CheckImplicitInitList(const InitializedEntity &Entity, 180 InitListExpr *ParentIList, QualType T, 181 unsigned &Index, InitListExpr *StructuredList, 182 unsigned &StructuredIndex); 183 void CheckExplicitInitList(const InitializedEntity &Entity, 184 InitListExpr *IList, QualType &T, 185 unsigned &Index, InitListExpr *StructuredList, 186 unsigned &StructuredIndex, 187 bool TopLevelObject = false); 188 void CheckListElementTypes(const InitializedEntity &Entity, 189 InitListExpr *IList, QualType &DeclType, 190 bool SubobjectIsDesignatorContext, 191 unsigned &Index, 192 InitListExpr *StructuredList, 193 unsigned &StructuredIndex, 194 bool TopLevelObject = false); 195 void CheckSubElementType(const InitializedEntity &Entity, 196 InitListExpr *IList, QualType ElemType, 197 unsigned &Index, 198 InitListExpr *StructuredList, 199 unsigned &StructuredIndex); 200 void CheckComplexType(const InitializedEntity &Entity, 201 InitListExpr *IList, QualType DeclType, 202 unsigned &Index, 203 InitListExpr *StructuredList, 204 unsigned &StructuredIndex); 205 void CheckScalarType(const InitializedEntity &Entity, 206 InitListExpr *IList, QualType DeclType, 207 unsigned &Index, 208 InitListExpr *StructuredList, 209 unsigned &StructuredIndex); 210 void CheckReferenceType(const InitializedEntity &Entity, 211 InitListExpr *IList, QualType DeclType, 212 unsigned &Index, 213 InitListExpr *StructuredList, 214 unsigned &StructuredIndex); 215 void CheckVectorType(const InitializedEntity &Entity, 216 InitListExpr *IList, QualType DeclType, unsigned &Index, 217 InitListExpr *StructuredList, 218 unsigned &StructuredIndex); 219 void CheckStructUnionTypes(const InitializedEntity &Entity, 220 InitListExpr *IList, QualType DeclType, 221 RecordDecl::field_iterator Field, 222 bool SubobjectIsDesignatorContext, unsigned &Index, 223 InitListExpr *StructuredList, 224 unsigned &StructuredIndex, 225 bool TopLevelObject = false); 226 void CheckArrayType(const InitializedEntity &Entity, 227 InitListExpr *IList, QualType &DeclType, 228 llvm::APSInt elementIndex, 229 bool SubobjectIsDesignatorContext, unsigned &Index, 230 InitListExpr *StructuredList, 231 unsigned &StructuredIndex); 232 bool CheckDesignatedInitializer(const InitializedEntity &Entity, 233 InitListExpr *IList, DesignatedInitExpr *DIE, 234 unsigned DesigIdx, 235 QualType &CurrentObjectType, 236 RecordDecl::field_iterator *NextField, 237 llvm::APSInt *NextElementIndex, 238 unsigned &Index, 239 InitListExpr *StructuredList, 240 unsigned &StructuredIndex, 241 bool FinishSubobjectInit, 242 bool TopLevelObject); 243 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 244 QualType CurrentObjectType, 245 InitListExpr *StructuredList, 246 unsigned StructuredIndex, 247 SourceRange InitRange); 248 void UpdateStructuredListElement(InitListExpr *StructuredList, 249 unsigned &StructuredIndex, 250 Expr *expr); 251 int numArrayElements(QualType DeclType); 252 int numStructUnionElements(QualType DeclType); 253 254 void FillInValueInitForField(unsigned Init, FieldDecl *Field, 255 const InitializedEntity &ParentEntity, 256 InitListExpr *ILE, bool &RequiresSecondPass); 257 void FillInValueInitializations(const InitializedEntity &Entity, 258 InitListExpr *ILE, bool &RequiresSecondPass); 259 bool CheckFlexibleArrayInit(const InitializedEntity &Entity, 260 Expr *InitExpr, FieldDecl *Field, 261 bool TopLevelObject); 262 void CheckValueInitializable(const InitializedEntity &Entity); 263 264 public: 265 InitListChecker(Sema &S, const InitializedEntity &Entity, 266 InitListExpr *IL, QualType &T, bool VerifyOnly, 267 bool AllowBraceElision); 268 bool HadError() { return hadError; } 269 270 // @brief Retrieves the fully-structured initializer list used for 271 // semantic analysis and code generation. 272 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; } 273 }; 274 } // end anonymous namespace 275 276 void InitListChecker::CheckValueInitializable(const InitializedEntity &Entity) { 277 assert(VerifyOnly && 278 "CheckValueInitializable is only inteded for verification mode."); 279 280 SourceLocation Loc; 281 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 282 true); 283 InitializationSequence InitSeq(SemaRef, Entity, Kind, 0, 0); 284 if (InitSeq.Failed()) 285 hadError = true; 286 } 287 288 void InitListChecker::FillInValueInitForField(unsigned Init, FieldDecl *Field, 289 const InitializedEntity &ParentEntity, 290 InitListExpr *ILE, 291 bool &RequiresSecondPass) { 292 SourceLocation Loc = ILE->getLocStart(); 293 unsigned NumInits = ILE->getNumInits(); 294 InitializedEntity MemberEntity 295 = InitializedEntity::InitializeMember(Field, &ParentEntity); 296 if (Init >= NumInits || !ILE->getInit(Init)) { 297 // FIXME: We probably don't need to handle references 298 // specially here, since value-initialization of references is 299 // handled in InitializationSequence. 300 if (Field->getType()->isReferenceType()) { 301 // C++ [dcl.init.aggr]p9: 302 // If an incomplete or empty initializer-list leaves a 303 // member of reference type uninitialized, the program is 304 // ill-formed. 305 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized) 306 << Field->getType() 307 << ILE->getSyntacticForm()->getSourceRange(); 308 SemaRef.Diag(Field->getLocation(), 309 diag::note_uninit_reference_member); 310 hadError = true; 311 return; 312 } 313 314 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 315 true); 316 InitializationSequence InitSeq(SemaRef, MemberEntity, Kind, 0, 0); 317 if (!InitSeq) { 318 InitSeq.Diagnose(SemaRef, MemberEntity, Kind, 0, 0); 319 hadError = true; 320 return; 321 } 322 323 ExprResult MemberInit 324 = InitSeq.Perform(SemaRef, MemberEntity, Kind, MultiExprArg()); 325 if (MemberInit.isInvalid()) { 326 hadError = true; 327 return; 328 } 329 330 if (hadError) { 331 // Do nothing 332 } else if (Init < NumInits) { 333 ILE->setInit(Init, MemberInit.takeAs<Expr>()); 334 } else if (InitSeq.isConstructorInitialization()) { 335 // Value-initialization requires a constructor call, so 336 // extend the initializer list to include the constructor 337 // call and make a note that we'll need to take another pass 338 // through the initializer list. 339 ILE->updateInit(SemaRef.Context, Init, MemberInit.takeAs<Expr>()); 340 RequiresSecondPass = true; 341 } 342 } else if (InitListExpr *InnerILE 343 = dyn_cast<InitListExpr>(ILE->getInit(Init))) 344 FillInValueInitializations(MemberEntity, InnerILE, 345 RequiresSecondPass); 346 } 347 348 /// Recursively replaces NULL values within the given initializer list 349 /// with expressions that perform value-initialization of the 350 /// appropriate type. 351 void 352 InitListChecker::FillInValueInitializations(const InitializedEntity &Entity, 353 InitListExpr *ILE, 354 bool &RequiresSecondPass) { 355 assert((ILE->getType() != SemaRef.Context.VoidTy) && 356 "Should not have void type"); 357 SourceLocation Loc = ILE->getLocStart(); 358 if (ILE->getSyntacticForm()) 359 Loc = ILE->getSyntacticForm()->getLocStart(); 360 361 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) { 362 if (RType->getDecl()->isUnion() && 363 ILE->getInitializedFieldInUnion()) 364 FillInValueInitForField(0, ILE->getInitializedFieldInUnion(), 365 Entity, ILE, RequiresSecondPass); 366 else { 367 unsigned Init = 0; 368 for (RecordDecl::field_iterator 369 Field = RType->getDecl()->field_begin(), 370 FieldEnd = RType->getDecl()->field_end(); 371 Field != FieldEnd; ++Field) { 372 if (Field->isUnnamedBitfield()) 373 continue; 374 375 if (hadError) 376 return; 377 378 FillInValueInitForField(Init, *Field, Entity, ILE, RequiresSecondPass); 379 if (hadError) 380 return; 381 382 ++Init; 383 384 // Only look at the first initialization of a union. 385 if (RType->getDecl()->isUnion()) 386 break; 387 } 388 } 389 390 return; 391 } 392 393 QualType ElementType; 394 395 InitializedEntity ElementEntity = Entity; 396 unsigned NumInits = ILE->getNumInits(); 397 unsigned NumElements = NumInits; 398 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) { 399 ElementType = AType->getElementType(); 400 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) 401 NumElements = CAType->getSize().getZExtValue(); 402 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, 403 0, Entity); 404 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) { 405 ElementType = VType->getElementType(); 406 NumElements = VType->getNumElements(); 407 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, 408 0, Entity); 409 } else 410 ElementType = ILE->getType(); 411 412 413 for (unsigned Init = 0; Init != NumElements; ++Init) { 414 if (hadError) 415 return; 416 417 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement || 418 ElementEntity.getKind() == InitializedEntity::EK_VectorElement) 419 ElementEntity.setElementIndex(Init); 420 421 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : 0); 422 if (!InitExpr && !ILE->hasArrayFiller()) { 423 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 424 true); 425 InitializationSequence InitSeq(SemaRef, ElementEntity, Kind, 0, 0); 426 if (!InitSeq) { 427 InitSeq.Diagnose(SemaRef, ElementEntity, Kind, 0, 0); 428 hadError = true; 429 return; 430 } 431 432 ExprResult ElementInit 433 = InitSeq.Perform(SemaRef, ElementEntity, Kind, MultiExprArg()); 434 if (ElementInit.isInvalid()) { 435 hadError = true; 436 return; 437 } 438 439 if (hadError) { 440 // Do nothing 441 } else if (Init < NumInits) { 442 // For arrays, just set the expression used for value-initialization 443 // of the "holes" in the array. 444 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) 445 ILE->setArrayFiller(ElementInit.takeAs<Expr>()); 446 else 447 ILE->setInit(Init, ElementInit.takeAs<Expr>()); 448 } else { 449 // For arrays, just set the expression used for value-initialization 450 // of the rest of elements and exit. 451 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) { 452 ILE->setArrayFiller(ElementInit.takeAs<Expr>()); 453 return; 454 } 455 456 if (InitSeq.isConstructorInitialization()) { 457 // Value-initialization requires a constructor call, so 458 // extend the initializer list to include the constructor 459 // call and make a note that we'll need to take another pass 460 // through the initializer list. 461 ILE->updateInit(SemaRef.Context, Init, ElementInit.takeAs<Expr>()); 462 RequiresSecondPass = true; 463 } 464 } 465 } else if (InitListExpr *InnerILE 466 = dyn_cast_or_null<InitListExpr>(InitExpr)) 467 FillInValueInitializations(ElementEntity, InnerILE, RequiresSecondPass); 468 } 469 } 470 471 472 InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity, 473 InitListExpr *IL, QualType &T, 474 bool VerifyOnly, bool AllowBraceElision) 475 : SemaRef(S), VerifyOnly(VerifyOnly), AllowBraceElision(AllowBraceElision) { 476 hadError = false; 477 478 unsigned newIndex = 0; 479 unsigned newStructuredIndex = 0; 480 FullyStructuredList 481 = getStructuredSubobjectInit(IL, newIndex, T, 0, 0, IL->getSourceRange()); 482 CheckExplicitInitList(Entity, IL, T, newIndex, 483 FullyStructuredList, newStructuredIndex, 484 /*TopLevelObject=*/true); 485 486 if (!hadError && !VerifyOnly) { 487 bool RequiresSecondPass = false; 488 FillInValueInitializations(Entity, FullyStructuredList, RequiresSecondPass); 489 if (RequiresSecondPass && !hadError) 490 FillInValueInitializations(Entity, FullyStructuredList, 491 RequiresSecondPass); 492 } 493 } 494 495 int InitListChecker::numArrayElements(QualType DeclType) { 496 // FIXME: use a proper constant 497 int maxElements = 0x7FFFFFFF; 498 if (const ConstantArrayType *CAT = 499 SemaRef.Context.getAsConstantArrayType(DeclType)) { 500 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 501 } 502 return maxElements; 503 } 504 505 int InitListChecker::numStructUnionElements(QualType DeclType) { 506 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl(); 507 int InitializableMembers = 0; 508 for (RecordDecl::field_iterator 509 Field = structDecl->field_begin(), 510 FieldEnd = structDecl->field_end(); 511 Field != FieldEnd; ++Field) { 512 if (!Field->isUnnamedBitfield()) 513 ++InitializableMembers; 514 } 515 if (structDecl->isUnion()) 516 return std::min(InitializableMembers, 1); 517 return InitializableMembers - structDecl->hasFlexibleArrayMember(); 518 } 519 520 void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity, 521 InitListExpr *ParentIList, 522 QualType T, unsigned &Index, 523 InitListExpr *StructuredList, 524 unsigned &StructuredIndex) { 525 int maxElements = 0; 526 527 if (T->isArrayType()) 528 maxElements = numArrayElements(T); 529 else if (T->isRecordType()) 530 maxElements = numStructUnionElements(T); 531 else if (T->isVectorType()) 532 maxElements = T->getAs<VectorType>()->getNumElements(); 533 else 534 llvm_unreachable("CheckImplicitInitList(): Illegal type"); 535 536 if (maxElements == 0) { 537 if (!VerifyOnly) 538 SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(), 539 diag::err_implicit_empty_initializer); 540 ++Index; 541 hadError = true; 542 return; 543 } 544 545 // Build a structured initializer list corresponding to this subobject. 546 InitListExpr *StructuredSubobjectInitList 547 = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList, 548 StructuredIndex, 549 SourceRange(ParentIList->getInit(Index)->getLocStart(), 550 ParentIList->getSourceRange().getEnd())); 551 unsigned StructuredSubobjectInitIndex = 0; 552 553 // Check the element types and build the structural subobject. 554 unsigned StartIndex = Index; 555 CheckListElementTypes(Entity, ParentIList, T, 556 /*SubobjectIsDesignatorContext=*/false, Index, 557 StructuredSubobjectInitList, 558 StructuredSubobjectInitIndex); 559 560 if (VerifyOnly) { 561 if (!AllowBraceElision && (T->isArrayType() || T->isRecordType())) 562 hadError = true; 563 } else { 564 StructuredSubobjectInitList->setType(T); 565 566 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1); 567 // Update the structured sub-object initializer so that it's ending 568 // range corresponds with the end of the last initializer it used. 569 if (EndIndex < ParentIList->getNumInits()) { 570 SourceLocation EndLoc 571 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd(); 572 StructuredSubobjectInitList->setRBraceLoc(EndLoc); 573 } 574 575 // Complain about missing braces. 576 if (T->isArrayType() || T->isRecordType()) { 577 SemaRef.Diag(StructuredSubobjectInitList->getLocStart(), 578 AllowBraceElision ? diag::warn_missing_braces : 579 diag::err_missing_braces) 580 << StructuredSubobjectInitList->getSourceRange() 581 << FixItHint::CreateInsertion( 582 StructuredSubobjectInitList->getLocStart(), "{") 583 << FixItHint::CreateInsertion( 584 SemaRef.PP.getLocForEndOfToken( 585 StructuredSubobjectInitList->getLocEnd()), 586 "}"); 587 if (!AllowBraceElision) 588 hadError = true; 589 } 590 } 591 } 592 593 void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity, 594 InitListExpr *IList, QualType &T, 595 unsigned &Index, 596 InitListExpr *StructuredList, 597 unsigned &StructuredIndex, 598 bool TopLevelObject) { 599 assert(IList->isExplicit() && "Illegal Implicit InitListExpr"); 600 if (!VerifyOnly) { 601 SyntacticToSemantic[IList] = StructuredList; 602 StructuredList->setSyntacticForm(IList); 603 } 604 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true, 605 Index, StructuredList, StructuredIndex, TopLevelObject); 606 if (!VerifyOnly) { 607 QualType ExprTy = T; 608 if (!ExprTy->isArrayType()) 609 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context); 610 IList->setType(ExprTy); 611 StructuredList->setType(ExprTy); 612 } 613 if (hadError) 614 return; 615 616 if (Index < IList->getNumInits()) { 617 // We have leftover initializers 618 if (VerifyOnly) { 619 if (SemaRef.getLangOpts().CPlusPlus || 620 (SemaRef.getLangOpts().OpenCL && 621 IList->getType()->isVectorType())) { 622 hadError = true; 623 } 624 return; 625 } 626 627 if (StructuredIndex == 1 && 628 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context)) { 629 unsigned DK = diag::warn_excess_initializers_in_char_array_initializer; 630 if (SemaRef.getLangOpts().CPlusPlus) { 631 DK = diag::err_excess_initializers_in_char_array_initializer; 632 hadError = true; 633 } 634 // Special-case 635 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) 636 << IList->getInit(Index)->getSourceRange(); 637 } else if (!T->isIncompleteType()) { 638 // Don't complain for incomplete types, since we'll get an error 639 // elsewhere 640 QualType CurrentObjectType = StructuredList->getType(); 641 int initKind = 642 CurrentObjectType->isArrayType()? 0 : 643 CurrentObjectType->isVectorType()? 1 : 644 CurrentObjectType->isScalarType()? 2 : 645 CurrentObjectType->isUnionType()? 3 : 646 4; 647 648 unsigned DK = diag::warn_excess_initializers; 649 if (SemaRef.getLangOpts().CPlusPlus) { 650 DK = diag::err_excess_initializers; 651 hadError = true; 652 } 653 if (SemaRef.getLangOpts().OpenCL && initKind == 1) { 654 DK = diag::err_excess_initializers; 655 hadError = true; 656 } 657 658 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) 659 << initKind << IList->getInit(Index)->getSourceRange(); 660 } 661 } 662 663 if (!VerifyOnly && T->isScalarType() && IList->getNumInits() == 1 && 664 !TopLevelObject) 665 SemaRef.Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init) 666 << IList->getSourceRange() 667 << FixItHint::CreateRemoval(IList->getLocStart()) 668 << FixItHint::CreateRemoval(IList->getLocEnd()); 669 } 670 671 void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity, 672 InitListExpr *IList, 673 QualType &DeclType, 674 bool SubobjectIsDesignatorContext, 675 unsigned &Index, 676 InitListExpr *StructuredList, 677 unsigned &StructuredIndex, 678 bool TopLevelObject) { 679 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) { 680 // Explicitly braced initializer for complex type can be real+imaginary 681 // parts. 682 CheckComplexType(Entity, IList, DeclType, Index, 683 StructuredList, StructuredIndex); 684 } else if (DeclType->isScalarType()) { 685 CheckScalarType(Entity, IList, DeclType, Index, 686 StructuredList, StructuredIndex); 687 } else if (DeclType->isVectorType()) { 688 CheckVectorType(Entity, IList, DeclType, Index, 689 StructuredList, StructuredIndex); 690 } else if (DeclType->isAggregateType()) { 691 if (DeclType->isRecordType()) { 692 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 693 CheckStructUnionTypes(Entity, IList, DeclType, RD->field_begin(), 694 SubobjectIsDesignatorContext, Index, 695 StructuredList, StructuredIndex, 696 TopLevelObject); 697 } else if (DeclType->isArrayType()) { 698 llvm::APSInt Zero( 699 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()), 700 false); 701 CheckArrayType(Entity, IList, DeclType, Zero, 702 SubobjectIsDesignatorContext, Index, 703 StructuredList, StructuredIndex); 704 } else 705 llvm_unreachable("Aggregate that isn't a structure or array?!"); 706 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) { 707 // This type is invalid, issue a diagnostic. 708 ++Index; 709 if (!VerifyOnly) 710 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) 711 << DeclType; 712 hadError = true; 713 } else if (DeclType->isRecordType()) { 714 // C++ [dcl.init]p14: 715 // [...] If the class is an aggregate (8.5.1), and the initializer 716 // is a brace-enclosed list, see 8.5.1. 717 // 718 // Note: 8.5.1 is handled below; here, we diagnose the case where 719 // we have an initializer list and a destination type that is not 720 // an aggregate. 721 // FIXME: In C++0x, this is yet another form of initialization. 722 if (!VerifyOnly) 723 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) 724 << DeclType << IList->getSourceRange(); 725 hadError = true; 726 } else if (DeclType->isReferenceType()) { 727 CheckReferenceType(Entity, IList, DeclType, Index, 728 StructuredList, StructuredIndex); 729 } else if (DeclType->isObjCObjectType()) { 730 if (!VerifyOnly) 731 SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class) 732 << DeclType; 733 hadError = true; 734 } else { 735 if (!VerifyOnly) 736 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) 737 << DeclType; 738 hadError = true; 739 } 740 } 741 742 void InitListChecker::CheckSubElementType(const InitializedEntity &Entity, 743 InitListExpr *IList, 744 QualType ElemType, 745 unsigned &Index, 746 InitListExpr *StructuredList, 747 unsigned &StructuredIndex) { 748 Expr *expr = IList->getInit(Index); 749 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 750 unsigned newIndex = 0; 751 unsigned newStructuredIndex = 0; 752 InitListExpr *newStructuredList 753 = getStructuredSubobjectInit(IList, Index, ElemType, 754 StructuredList, StructuredIndex, 755 SubInitList->getSourceRange()); 756 CheckExplicitInitList(Entity, SubInitList, ElemType, newIndex, 757 newStructuredList, newStructuredIndex); 758 ++StructuredIndex; 759 ++Index; 760 return; 761 } else if (ElemType->isScalarType()) { 762 return CheckScalarType(Entity, IList, ElemType, Index, 763 StructuredList, StructuredIndex); 764 } else if (ElemType->isReferenceType()) { 765 return CheckReferenceType(Entity, IList, ElemType, Index, 766 StructuredList, StructuredIndex); 767 } 768 769 if (const ArrayType *arrayType = SemaRef.Context.getAsArrayType(ElemType)) { 770 // arrayType can be incomplete if we're initializing a flexible 771 // array member. There's nothing we can do with the completed 772 // type here, though. 773 774 if (Expr *Str = IsStringInit(expr, arrayType, SemaRef.Context)) { 775 if (!VerifyOnly) { 776 CheckStringInit(Str, ElemType, arrayType, SemaRef); 777 UpdateStructuredListElement(StructuredList, StructuredIndex, Str); 778 } 779 ++Index; 780 return; 781 } 782 783 // Fall through for subaggregate initialization. 784 785 } else if (SemaRef.getLangOpts().CPlusPlus) { 786 // C++ [dcl.init.aggr]p12: 787 // All implicit type conversions (clause 4) are considered when 788 // initializing the aggregate member with an initializer from 789 // an initializer-list. If the initializer can initialize a 790 // member, the member is initialized. [...] 791 792 // FIXME: Better EqualLoc? 793 InitializationKind Kind = 794 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation()); 795 InitializationSequence Seq(SemaRef, Entity, Kind, &expr, 1); 796 797 if (Seq) { 798 if (!VerifyOnly) { 799 ExprResult Result = 800 Seq.Perform(SemaRef, Entity, Kind, MultiExprArg(&expr, 1)); 801 if (Result.isInvalid()) 802 hadError = true; 803 804 UpdateStructuredListElement(StructuredList, StructuredIndex, 805 Result.takeAs<Expr>()); 806 } 807 ++Index; 808 return; 809 } 810 811 // Fall through for subaggregate initialization 812 } else { 813 // C99 6.7.8p13: 814 // 815 // The initializer for a structure or union object that has 816 // automatic storage duration shall be either an initializer 817 // list as described below, or a single expression that has 818 // compatible structure or union type. In the latter case, the 819 // initial value of the object, including unnamed members, is 820 // that of the expression. 821 ExprResult ExprRes = SemaRef.Owned(expr); 822 if ((ElemType->isRecordType() || ElemType->isVectorType()) && 823 SemaRef.CheckSingleAssignmentConstraints(ElemType, ExprRes, 824 !VerifyOnly) 825 == Sema::Compatible) { 826 if (ExprRes.isInvalid()) 827 hadError = true; 828 else { 829 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.take()); 830 if (ExprRes.isInvalid()) 831 hadError = true; 832 } 833 UpdateStructuredListElement(StructuredList, StructuredIndex, 834 ExprRes.takeAs<Expr>()); 835 ++Index; 836 return; 837 } 838 ExprRes.release(); 839 // Fall through for subaggregate initialization 840 } 841 842 // C++ [dcl.init.aggr]p12: 843 // 844 // [...] Otherwise, if the member is itself a non-empty 845 // subaggregate, brace elision is assumed and the initializer is 846 // considered for the initialization of the first member of 847 // the subaggregate. 848 if (!SemaRef.getLangOpts().OpenCL && 849 (ElemType->isAggregateType() || ElemType->isVectorType())) { 850 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList, 851 StructuredIndex); 852 ++StructuredIndex; 853 } else { 854 if (!VerifyOnly) { 855 // We cannot initialize this element, so let 856 // PerformCopyInitialization produce the appropriate diagnostic. 857 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), 858 SemaRef.Owned(expr), 859 /*TopLevelOfInitList=*/true); 860 } 861 hadError = true; 862 ++Index; 863 ++StructuredIndex; 864 } 865 } 866 867 void InitListChecker::CheckComplexType(const InitializedEntity &Entity, 868 InitListExpr *IList, QualType DeclType, 869 unsigned &Index, 870 InitListExpr *StructuredList, 871 unsigned &StructuredIndex) { 872 assert(Index == 0 && "Index in explicit init list must be zero"); 873 874 // As an extension, clang supports complex initializers, which initialize 875 // a complex number component-wise. When an explicit initializer list for 876 // a complex number contains two two initializers, this extension kicks in: 877 // it exepcts the initializer list to contain two elements convertible to 878 // the element type of the complex type. The first element initializes 879 // the real part, and the second element intitializes the imaginary part. 880 881 if (IList->getNumInits() != 2) 882 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList, 883 StructuredIndex); 884 885 // This is an extension in C. (The builtin _Complex type does not exist 886 // in the C++ standard.) 887 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly) 888 SemaRef.Diag(IList->getLocStart(), diag::ext_complex_component_init) 889 << IList->getSourceRange(); 890 891 // Initialize the complex number. 892 QualType elementType = DeclType->getAs<ComplexType>()->getElementType(); 893 InitializedEntity ElementEntity = 894 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 895 896 for (unsigned i = 0; i < 2; ++i) { 897 ElementEntity.setElementIndex(Index); 898 CheckSubElementType(ElementEntity, IList, elementType, Index, 899 StructuredList, StructuredIndex); 900 } 901 } 902 903 904 void InitListChecker::CheckScalarType(const InitializedEntity &Entity, 905 InitListExpr *IList, QualType DeclType, 906 unsigned &Index, 907 InitListExpr *StructuredList, 908 unsigned &StructuredIndex) { 909 if (Index >= IList->getNumInits()) { 910 if (!VerifyOnly) 911 SemaRef.Diag(IList->getLocStart(), 912 SemaRef.getLangOpts().CPlusPlus0x ? 913 diag::warn_cxx98_compat_empty_scalar_initializer : 914 diag::err_empty_scalar_initializer) 915 << IList->getSourceRange(); 916 hadError = !SemaRef.getLangOpts().CPlusPlus0x; 917 ++Index; 918 ++StructuredIndex; 919 return; 920 } 921 922 Expr *expr = IList->getInit(Index); 923 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) { 924 if (!VerifyOnly) 925 SemaRef.Diag(SubIList->getLocStart(), 926 diag::warn_many_braces_around_scalar_init) 927 << SubIList->getSourceRange(); 928 929 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList, 930 StructuredIndex); 931 return; 932 } else if (isa<DesignatedInitExpr>(expr)) { 933 if (!VerifyOnly) 934 SemaRef.Diag(expr->getLocStart(), 935 diag::err_designator_for_scalar_init) 936 << DeclType << expr->getSourceRange(); 937 hadError = true; 938 ++Index; 939 ++StructuredIndex; 940 return; 941 } 942 943 if (VerifyOnly) { 944 if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(expr))) 945 hadError = true; 946 ++Index; 947 return; 948 } 949 950 ExprResult Result = 951 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 952 SemaRef.Owned(expr), 953 /*TopLevelOfInitList=*/true); 954 955 Expr *ResultExpr = 0; 956 957 if (Result.isInvalid()) 958 hadError = true; // types weren't compatible. 959 else { 960 ResultExpr = Result.takeAs<Expr>(); 961 962 if (ResultExpr != expr) { 963 // The type was promoted, update initializer list. 964 IList->setInit(Index, ResultExpr); 965 } 966 } 967 if (hadError) 968 ++StructuredIndex; 969 else 970 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr); 971 ++Index; 972 } 973 974 void InitListChecker::CheckReferenceType(const InitializedEntity &Entity, 975 InitListExpr *IList, QualType DeclType, 976 unsigned &Index, 977 InitListExpr *StructuredList, 978 unsigned &StructuredIndex) { 979 if (Index >= IList->getNumInits()) { 980 // FIXME: It would be wonderful if we could point at the actual member. In 981 // general, it would be useful to pass location information down the stack, 982 // so that we know the location (or decl) of the "current object" being 983 // initialized. 984 if (!VerifyOnly) 985 SemaRef.Diag(IList->getLocStart(), 986 diag::err_init_reference_member_uninitialized) 987 << DeclType 988 << IList->getSourceRange(); 989 hadError = true; 990 ++Index; 991 ++StructuredIndex; 992 return; 993 } 994 995 Expr *expr = IList->getInit(Index); 996 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus0x) { 997 if (!VerifyOnly) 998 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) 999 << DeclType << IList->getSourceRange(); 1000 hadError = true; 1001 ++Index; 1002 ++StructuredIndex; 1003 return; 1004 } 1005 1006 if (VerifyOnly) { 1007 if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(expr))) 1008 hadError = true; 1009 ++Index; 1010 return; 1011 } 1012 1013 ExprResult Result = 1014 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 1015 SemaRef.Owned(expr), 1016 /*TopLevelOfInitList=*/true); 1017 1018 if (Result.isInvalid()) 1019 hadError = true; 1020 1021 expr = Result.takeAs<Expr>(); 1022 IList->setInit(Index, expr); 1023 1024 if (hadError) 1025 ++StructuredIndex; 1026 else 1027 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 1028 ++Index; 1029 } 1030 1031 void InitListChecker::CheckVectorType(const InitializedEntity &Entity, 1032 InitListExpr *IList, QualType DeclType, 1033 unsigned &Index, 1034 InitListExpr *StructuredList, 1035 unsigned &StructuredIndex) { 1036 const VectorType *VT = DeclType->getAs<VectorType>(); 1037 unsigned maxElements = VT->getNumElements(); 1038 unsigned numEltsInit = 0; 1039 QualType elementType = VT->getElementType(); 1040 1041 if (Index >= IList->getNumInits()) { 1042 // Make sure the element type can be value-initialized. 1043 if (VerifyOnly) 1044 CheckValueInitializable( 1045 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity)); 1046 return; 1047 } 1048 1049 if (!SemaRef.getLangOpts().OpenCL) { 1050 // If the initializing element is a vector, try to copy-initialize 1051 // instead of breaking it apart (which is doomed to failure anyway). 1052 Expr *Init = IList->getInit(Index); 1053 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) { 1054 if (VerifyOnly) { 1055 if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(Init))) 1056 hadError = true; 1057 ++Index; 1058 return; 1059 } 1060 1061 ExprResult Result = 1062 SemaRef.PerformCopyInitialization(Entity, Init->getLocStart(), 1063 SemaRef.Owned(Init), 1064 /*TopLevelOfInitList=*/true); 1065 1066 Expr *ResultExpr = 0; 1067 if (Result.isInvalid()) 1068 hadError = true; // types weren't compatible. 1069 else { 1070 ResultExpr = Result.takeAs<Expr>(); 1071 1072 if (ResultExpr != Init) { 1073 // The type was promoted, update initializer list. 1074 IList->setInit(Index, ResultExpr); 1075 } 1076 } 1077 if (hadError) 1078 ++StructuredIndex; 1079 else 1080 UpdateStructuredListElement(StructuredList, StructuredIndex, 1081 ResultExpr); 1082 ++Index; 1083 return; 1084 } 1085 1086 InitializedEntity ElementEntity = 1087 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1088 1089 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) { 1090 // Don't attempt to go past the end of the init list 1091 if (Index >= IList->getNumInits()) { 1092 if (VerifyOnly) 1093 CheckValueInitializable(ElementEntity); 1094 break; 1095 } 1096 1097 ElementEntity.setElementIndex(Index); 1098 CheckSubElementType(ElementEntity, IList, elementType, Index, 1099 StructuredList, StructuredIndex); 1100 } 1101 return; 1102 } 1103 1104 InitializedEntity ElementEntity = 1105 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1106 1107 // OpenCL initializers allows vectors to be constructed from vectors. 1108 for (unsigned i = 0; i < maxElements; ++i) { 1109 // Don't attempt to go past the end of the init list 1110 if (Index >= IList->getNumInits()) 1111 break; 1112 1113 ElementEntity.setElementIndex(Index); 1114 1115 QualType IType = IList->getInit(Index)->getType(); 1116 if (!IType->isVectorType()) { 1117 CheckSubElementType(ElementEntity, IList, elementType, Index, 1118 StructuredList, StructuredIndex); 1119 ++numEltsInit; 1120 } else { 1121 QualType VecType; 1122 const VectorType *IVT = IType->getAs<VectorType>(); 1123 unsigned numIElts = IVT->getNumElements(); 1124 1125 if (IType->isExtVectorType()) 1126 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts); 1127 else 1128 VecType = SemaRef.Context.getVectorType(elementType, numIElts, 1129 IVT->getVectorKind()); 1130 CheckSubElementType(ElementEntity, IList, VecType, Index, 1131 StructuredList, StructuredIndex); 1132 numEltsInit += numIElts; 1133 } 1134 } 1135 1136 // OpenCL requires all elements to be initialized. 1137 if (numEltsInit != maxElements) { 1138 if (!VerifyOnly) 1139 SemaRef.Diag(IList->getLocStart(), 1140 diag::err_vector_incorrect_num_initializers) 1141 << (numEltsInit < maxElements) << maxElements << numEltsInit; 1142 hadError = true; 1143 } 1144 } 1145 1146 void InitListChecker::CheckArrayType(const InitializedEntity &Entity, 1147 InitListExpr *IList, QualType &DeclType, 1148 llvm::APSInt elementIndex, 1149 bool SubobjectIsDesignatorContext, 1150 unsigned &Index, 1151 InitListExpr *StructuredList, 1152 unsigned &StructuredIndex) { 1153 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType); 1154 1155 // Check for the special-case of initializing an array with a string. 1156 if (Index < IList->getNumInits()) { 1157 if (Expr *Str = IsStringInit(IList->getInit(Index), arrayType, 1158 SemaRef.Context)) { 1159 // We place the string literal directly into the resulting 1160 // initializer list. This is the only place where the structure 1161 // of the structured initializer list doesn't match exactly, 1162 // because doing so would involve allocating one character 1163 // constant for each string. 1164 if (!VerifyOnly) { 1165 CheckStringInit(Str, DeclType, arrayType, SemaRef); 1166 UpdateStructuredListElement(StructuredList, StructuredIndex, Str); 1167 StructuredList->resizeInits(SemaRef.Context, StructuredIndex); 1168 } 1169 ++Index; 1170 return; 1171 } 1172 } 1173 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) { 1174 // Check for VLAs; in standard C it would be possible to check this 1175 // earlier, but I don't know where clang accepts VLAs (gcc accepts 1176 // them in all sorts of strange places). 1177 if (!VerifyOnly) 1178 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(), 1179 diag::err_variable_object_no_init) 1180 << VAT->getSizeExpr()->getSourceRange(); 1181 hadError = true; 1182 ++Index; 1183 ++StructuredIndex; 1184 return; 1185 } 1186 1187 // We might know the maximum number of elements in advance. 1188 llvm::APSInt maxElements(elementIndex.getBitWidth(), 1189 elementIndex.isUnsigned()); 1190 bool maxElementsKnown = false; 1191 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) { 1192 maxElements = CAT->getSize(); 1193 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth()); 1194 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 1195 maxElementsKnown = true; 1196 } 1197 1198 QualType elementType = arrayType->getElementType(); 1199 while (Index < IList->getNumInits()) { 1200 Expr *Init = IList->getInit(Index); 1201 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 1202 // If we're not the subobject that matches up with the '{' for 1203 // the designator, we shouldn't be handling the 1204 // designator. Return immediately. 1205 if (!SubobjectIsDesignatorContext) 1206 return; 1207 1208 // Handle this designated initializer. elementIndex will be 1209 // updated to be the next array element we'll initialize. 1210 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 1211 DeclType, 0, &elementIndex, Index, 1212 StructuredList, StructuredIndex, true, 1213 false)) { 1214 hadError = true; 1215 continue; 1216 } 1217 1218 if (elementIndex.getBitWidth() > maxElements.getBitWidth()) 1219 maxElements = maxElements.extend(elementIndex.getBitWidth()); 1220 else if (elementIndex.getBitWidth() < maxElements.getBitWidth()) 1221 elementIndex = elementIndex.extend(maxElements.getBitWidth()); 1222 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 1223 1224 // If the array is of incomplete type, keep track of the number of 1225 // elements in the initializer. 1226 if (!maxElementsKnown && elementIndex > maxElements) 1227 maxElements = elementIndex; 1228 1229 continue; 1230 } 1231 1232 // If we know the maximum number of elements, and we've already 1233 // hit it, stop consuming elements in the initializer list. 1234 if (maxElementsKnown && elementIndex == maxElements) 1235 break; 1236 1237 InitializedEntity ElementEntity = 1238 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex, 1239 Entity); 1240 // Check this element. 1241 CheckSubElementType(ElementEntity, IList, elementType, Index, 1242 StructuredList, StructuredIndex); 1243 ++elementIndex; 1244 1245 // If the array is of incomplete type, keep track of the number of 1246 // elements in the initializer. 1247 if (!maxElementsKnown && elementIndex > maxElements) 1248 maxElements = elementIndex; 1249 } 1250 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) { 1251 // If this is an incomplete array type, the actual type needs to 1252 // be calculated here. 1253 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned()); 1254 if (maxElements == Zero) { 1255 // Sizing an array implicitly to zero is not allowed by ISO C, 1256 // but is supported by GNU. 1257 SemaRef.Diag(IList->getLocStart(), 1258 diag::ext_typecheck_zero_array_size); 1259 } 1260 1261 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements, 1262 ArrayType::Normal, 0); 1263 } 1264 if (!hadError && VerifyOnly) { 1265 // Check if there are any members of the array that get value-initialized. 1266 // If so, check if doing that is possible. 1267 // FIXME: This needs to detect holes left by designated initializers too. 1268 if (maxElementsKnown && elementIndex < maxElements) 1269 CheckValueInitializable(InitializedEntity::InitializeElement( 1270 SemaRef.Context, 0, Entity)); 1271 } 1272 } 1273 1274 bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity, 1275 Expr *InitExpr, 1276 FieldDecl *Field, 1277 bool TopLevelObject) { 1278 // Handle GNU flexible array initializers. 1279 unsigned FlexArrayDiag; 1280 if (isa<InitListExpr>(InitExpr) && 1281 cast<InitListExpr>(InitExpr)->getNumInits() == 0) { 1282 // Empty flexible array init always allowed as an extension 1283 FlexArrayDiag = diag::ext_flexible_array_init; 1284 } else if (SemaRef.getLangOpts().CPlusPlus) { 1285 // Disallow flexible array init in C++; it is not required for gcc 1286 // compatibility, and it needs work to IRGen correctly in general. 1287 FlexArrayDiag = diag::err_flexible_array_init; 1288 } else if (!TopLevelObject) { 1289 // Disallow flexible array init on non-top-level object 1290 FlexArrayDiag = diag::err_flexible_array_init; 1291 } else if (Entity.getKind() != InitializedEntity::EK_Variable) { 1292 // Disallow flexible array init on anything which is not a variable. 1293 FlexArrayDiag = diag::err_flexible_array_init; 1294 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) { 1295 // Disallow flexible array init on local variables. 1296 FlexArrayDiag = diag::err_flexible_array_init; 1297 } else { 1298 // Allow other cases. 1299 FlexArrayDiag = diag::ext_flexible_array_init; 1300 } 1301 1302 if (!VerifyOnly) { 1303 SemaRef.Diag(InitExpr->getLocStart(), 1304 FlexArrayDiag) 1305 << InitExpr->getLocStart(); 1306 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1307 << Field; 1308 } 1309 1310 return FlexArrayDiag != diag::ext_flexible_array_init; 1311 } 1312 1313 void InitListChecker::CheckStructUnionTypes(const InitializedEntity &Entity, 1314 InitListExpr *IList, 1315 QualType DeclType, 1316 RecordDecl::field_iterator Field, 1317 bool SubobjectIsDesignatorContext, 1318 unsigned &Index, 1319 InitListExpr *StructuredList, 1320 unsigned &StructuredIndex, 1321 bool TopLevelObject) { 1322 RecordDecl* structDecl = DeclType->getAs<RecordType>()->getDecl(); 1323 1324 // If the record is invalid, some of it's members are invalid. To avoid 1325 // confusion, we forgo checking the intializer for the entire record. 1326 if (structDecl->isInvalidDecl()) { 1327 hadError = true; 1328 return; 1329 } 1330 1331 if (DeclType->isUnionType() && IList->getNumInits() == 0) { 1332 // Value-initialize the first named member of the union. 1333 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1334 for (RecordDecl::field_iterator FieldEnd = RD->field_end(); 1335 Field != FieldEnd; ++Field) { 1336 if (Field->getDeclName()) { 1337 if (VerifyOnly) 1338 CheckValueInitializable( 1339 InitializedEntity::InitializeMember(*Field, &Entity)); 1340 else 1341 StructuredList->setInitializedFieldInUnion(*Field); 1342 break; 1343 } 1344 } 1345 return; 1346 } 1347 1348 // If structDecl is a forward declaration, this loop won't do 1349 // anything except look at designated initializers; That's okay, 1350 // because an error should get printed out elsewhere. It might be 1351 // worthwhile to skip over the rest of the initializer, though. 1352 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1353 RecordDecl::field_iterator FieldEnd = RD->field_end(); 1354 bool InitializedSomething = false; 1355 bool CheckForMissingFields = true; 1356 while (Index < IList->getNumInits()) { 1357 Expr *Init = IList->getInit(Index); 1358 1359 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 1360 // If we're not the subobject that matches up with the '{' for 1361 // the designator, we shouldn't be handling the 1362 // designator. Return immediately. 1363 if (!SubobjectIsDesignatorContext) 1364 return; 1365 1366 // Handle this designated initializer. Field will be updated to 1367 // the next field that we'll be initializing. 1368 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 1369 DeclType, &Field, 0, Index, 1370 StructuredList, StructuredIndex, 1371 true, TopLevelObject)) 1372 hadError = true; 1373 1374 InitializedSomething = true; 1375 1376 // Disable check for missing fields when designators are used. 1377 // This matches gcc behaviour. 1378 CheckForMissingFields = false; 1379 continue; 1380 } 1381 1382 if (Field == FieldEnd) { 1383 // We've run out of fields. We're done. 1384 break; 1385 } 1386 1387 // We've already initialized a member of a union. We're done. 1388 if (InitializedSomething && DeclType->isUnionType()) 1389 break; 1390 1391 // If we've hit the flexible array member at the end, we're done. 1392 if (Field->getType()->isIncompleteArrayType()) 1393 break; 1394 1395 if (Field->isUnnamedBitfield()) { 1396 // Don't initialize unnamed bitfields, e.g. "int : 20;" 1397 ++Field; 1398 continue; 1399 } 1400 1401 // Make sure we can use this declaration. 1402 bool InvalidUse; 1403 if (VerifyOnly) 1404 InvalidUse = !SemaRef.CanUseDecl(*Field); 1405 else 1406 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, 1407 IList->getInit(Index)->getLocStart()); 1408 if (InvalidUse) { 1409 ++Index; 1410 ++Field; 1411 hadError = true; 1412 continue; 1413 } 1414 1415 InitializedEntity MemberEntity = 1416 InitializedEntity::InitializeMember(*Field, &Entity); 1417 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1418 StructuredList, StructuredIndex); 1419 InitializedSomething = true; 1420 1421 if (DeclType->isUnionType() && !VerifyOnly) { 1422 // Initialize the first field within the union. 1423 StructuredList->setInitializedFieldInUnion(*Field); 1424 } 1425 1426 ++Field; 1427 } 1428 1429 // Emit warnings for missing struct field initializers. 1430 if (!VerifyOnly && InitializedSomething && CheckForMissingFields && 1431 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() && 1432 !DeclType->isUnionType()) { 1433 // It is possible we have one or more unnamed bitfields remaining. 1434 // Find first (if any) named field and emit warning. 1435 for (RecordDecl::field_iterator it = Field, end = RD->field_end(); 1436 it != end; ++it) { 1437 if (!it->isUnnamedBitfield()) { 1438 SemaRef.Diag(IList->getSourceRange().getEnd(), 1439 diag::warn_missing_field_initializers) << it->getName(); 1440 break; 1441 } 1442 } 1443 } 1444 1445 // Check that any remaining fields can be value-initialized. 1446 if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() && 1447 !Field->getType()->isIncompleteArrayType()) { 1448 // FIXME: Should check for holes left by designated initializers too. 1449 for (; Field != FieldEnd && !hadError; ++Field) { 1450 if (!Field->isUnnamedBitfield()) 1451 CheckValueInitializable( 1452 InitializedEntity::InitializeMember(*Field, &Entity)); 1453 } 1454 } 1455 1456 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() || 1457 Index >= IList->getNumInits()) 1458 return; 1459 1460 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field, 1461 TopLevelObject)) { 1462 hadError = true; 1463 ++Index; 1464 return; 1465 } 1466 1467 InitializedEntity MemberEntity = 1468 InitializedEntity::InitializeMember(*Field, &Entity); 1469 1470 if (isa<InitListExpr>(IList->getInit(Index))) 1471 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1472 StructuredList, StructuredIndex); 1473 else 1474 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index, 1475 StructuredList, StructuredIndex); 1476 } 1477 1478 /// \brief Expand a field designator that refers to a member of an 1479 /// anonymous struct or union into a series of field designators that 1480 /// refers to the field within the appropriate subobject. 1481 /// 1482 static void ExpandAnonymousFieldDesignator(Sema &SemaRef, 1483 DesignatedInitExpr *DIE, 1484 unsigned DesigIdx, 1485 IndirectFieldDecl *IndirectField) { 1486 typedef DesignatedInitExpr::Designator Designator; 1487 1488 // Build the replacement designators. 1489 SmallVector<Designator, 4> Replacements; 1490 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(), 1491 PE = IndirectField->chain_end(); PI != PE; ++PI) { 1492 if (PI + 1 == PE) 1493 Replacements.push_back(Designator((IdentifierInfo *)0, 1494 DIE->getDesignator(DesigIdx)->getDotLoc(), 1495 DIE->getDesignator(DesigIdx)->getFieldLoc())); 1496 else 1497 Replacements.push_back(Designator((IdentifierInfo *)0, SourceLocation(), 1498 SourceLocation())); 1499 assert(isa<FieldDecl>(*PI)); 1500 Replacements.back().setField(cast<FieldDecl>(*PI)); 1501 } 1502 1503 // Expand the current designator into the set of replacement 1504 // designators, so we have a full subobject path down to where the 1505 // member of the anonymous struct/union is actually stored. 1506 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0], 1507 &Replacements[0] + Replacements.size()); 1508 } 1509 1510 /// \brief Given an implicit anonymous field, search the IndirectField that 1511 /// corresponds to FieldName. 1512 static IndirectFieldDecl *FindIndirectFieldDesignator(FieldDecl *AnonField, 1513 IdentifierInfo *FieldName) { 1514 assert(AnonField->isAnonymousStructOrUnion()); 1515 Decl *NextDecl = AnonField->getNextDeclInContext(); 1516 while (IndirectFieldDecl *IF = 1517 dyn_cast_or_null<IndirectFieldDecl>(NextDecl)) { 1518 if (FieldName && FieldName == IF->getAnonField()->getIdentifier()) 1519 return IF; 1520 NextDecl = NextDecl->getNextDeclInContext(); 1521 } 1522 return 0; 1523 } 1524 1525 static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef, 1526 DesignatedInitExpr *DIE) { 1527 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1; 1528 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs); 1529 for (unsigned I = 0; I < NumIndexExprs; ++I) 1530 IndexExprs[I] = DIE->getSubExpr(I + 1); 1531 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators_begin(), 1532 DIE->size(), IndexExprs.data(), 1533 NumIndexExprs, DIE->getEqualOrColonLoc(), 1534 DIE->usesGNUSyntax(), DIE->getInit()); 1535 } 1536 1537 namespace { 1538 1539 // Callback to only accept typo corrections that are for field members of 1540 // the given struct or union. 1541 class FieldInitializerValidatorCCC : public CorrectionCandidateCallback { 1542 public: 1543 explicit FieldInitializerValidatorCCC(RecordDecl *RD) 1544 : Record(RD) {} 1545 1546 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 1547 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>(); 1548 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record); 1549 } 1550 1551 private: 1552 RecordDecl *Record; 1553 }; 1554 1555 } 1556 1557 /// @brief Check the well-formedness of a C99 designated initializer. 1558 /// 1559 /// Determines whether the designated initializer @p DIE, which 1560 /// resides at the given @p Index within the initializer list @p 1561 /// IList, is well-formed for a current object of type @p DeclType 1562 /// (C99 6.7.8). The actual subobject that this designator refers to 1563 /// within the current subobject is returned in either 1564 /// @p NextField or @p NextElementIndex (whichever is appropriate). 1565 /// 1566 /// @param IList The initializer list in which this designated 1567 /// initializer occurs. 1568 /// 1569 /// @param DIE The designated initializer expression. 1570 /// 1571 /// @param DesigIdx The index of the current designator. 1572 /// 1573 /// @param DeclType The type of the "current object" (C99 6.7.8p17), 1574 /// into which the designation in @p DIE should refer. 1575 /// 1576 /// @param NextField If non-NULL and the first designator in @p DIE is 1577 /// a field, this will be set to the field declaration corresponding 1578 /// to the field named by the designator. 1579 /// 1580 /// @param NextElementIndex If non-NULL and the first designator in @p 1581 /// DIE is an array designator or GNU array-range designator, this 1582 /// will be set to the last index initialized by this designator. 1583 /// 1584 /// @param Index Index into @p IList where the designated initializer 1585 /// @p DIE occurs. 1586 /// 1587 /// @param StructuredList The initializer list expression that 1588 /// describes all of the subobject initializers in the order they'll 1589 /// actually be initialized. 1590 /// 1591 /// @returns true if there was an error, false otherwise. 1592 bool 1593 InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, 1594 InitListExpr *IList, 1595 DesignatedInitExpr *DIE, 1596 unsigned DesigIdx, 1597 QualType &CurrentObjectType, 1598 RecordDecl::field_iterator *NextField, 1599 llvm::APSInt *NextElementIndex, 1600 unsigned &Index, 1601 InitListExpr *StructuredList, 1602 unsigned &StructuredIndex, 1603 bool FinishSubobjectInit, 1604 bool TopLevelObject) { 1605 if (DesigIdx == DIE->size()) { 1606 // Check the actual initialization for the designated object type. 1607 bool prevHadError = hadError; 1608 1609 // Temporarily remove the designator expression from the 1610 // initializer list that the child calls see, so that we don't try 1611 // to re-process the designator. 1612 unsigned OldIndex = Index; 1613 IList->setInit(OldIndex, DIE->getInit()); 1614 1615 CheckSubElementType(Entity, IList, CurrentObjectType, Index, 1616 StructuredList, StructuredIndex); 1617 1618 // Restore the designated initializer expression in the syntactic 1619 // form of the initializer list. 1620 if (IList->getInit(OldIndex) != DIE->getInit()) 1621 DIE->setInit(IList->getInit(OldIndex)); 1622 IList->setInit(OldIndex, DIE); 1623 1624 return hadError && !prevHadError; 1625 } 1626 1627 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx); 1628 bool IsFirstDesignator = (DesigIdx == 0); 1629 if (!VerifyOnly) { 1630 assert((IsFirstDesignator || StructuredList) && 1631 "Need a non-designated initializer list to start from"); 1632 1633 // Determine the structural initializer list that corresponds to the 1634 // current subobject. 1635 StructuredList = IsFirstDesignator? SyntacticToSemantic.lookup(IList) 1636 : getStructuredSubobjectInit(IList, Index, CurrentObjectType, 1637 StructuredList, StructuredIndex, 1638 SourceRange(D->getStartLocation(), 1639 DIE->getSourceRange().getEnd())); 1640 assert(StructuredList && "Expected a structured initializer list"); 1641 } 1642 1643 if (D->isFieldDesignator()) { 1644 // C99 6.7.8p7: 1645 // 1646 // If a designator has the form 1647 // 1648 // . identifier 1649 // 1650 // then the current object (defined below) shall have 1651 // structure or union type and the identifier shall be the 1652 // name of a member of that type. 1653 const RecordType *RT = CurrentObjectType->getAs<RecordType>(); 1654 if (!RT) { 1655 SourceLocation Loc = D->getDotLoc(); 1656 if (Loc.isInvalid()) 1657 Loc = D->getFieldLoc(); 1658 if (!VerifyOnly) 1659 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr) 1660 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType; 1661 ++Index; 1662 return true; 1663 } 1664 1665 // Note: we perform a linear search of the fields here, despite 1666 // the fact that we have a faster lookup method, because we always 1667 // need to compute the field's index. 1668 FieldDecl *KnownField = D->getField(); 1669 IdentifierInfo *FieldName = D->getFieldName(); 1670 unsigned FieldIndex = 0; 1671 RecordDecl::field_iterator 1672 Field = RT->getDecl()->field_begin(), 1673 FieldEnd = RT->getDecl()->field_end(); 1674 for (; Field != FieldEnd; ++Field) { 1675 if (Field->isUnnamedBitfield()) 1676 continue; 1677 1678 // If we find a field representing an anonymous field, look in the 1679 // IndirectFieldDecl that follow for the designated initializer. 1680 if (!KnownField && Field->isAnonymousStructOrUnion()) { 1681 if (IndirectFieldDecl *IF = 1682 FindIndirectFieldDesignator(*Field, FieldName)) { 1683 // In verify mode, don't modify the original. 1684 if (VerifyOnly) 1685 DIE = CloneDesignatedInitExpr(SemaRef, DIE); 1686 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IF); 1687 D = DIE->getDesignator(DesigIdx); 1688 break; 1689 } 1690 } 1691 if (KnownField && KnownField == *Field) 1692 break; 1693 if (FieldName && FieldName == Field->getIdentifier()) 1694 break; 1695 1696 ++FieldIndex; 1697 } 1698 1699 if (Field == FieldEnd) { 1700 if (VerifyOnly) { 1701 ++Index; 1702 return true; // No typo correction when just trying this out. 1703 } 1704 1705 // There was no normal field in the struct with the designated 1706 // name. Perform another lookup for this name, which may find 1707 // something that we can't designate (e.g., a member function), 1708 // may find nothing, or may find a member of an anonymous 1709 // struct/union. 1710 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName); 1711 FieldDecl *ReplacementField = 0; 1712 if (Lookup.first == Lookup.second) { 1713 // Name lookup didn't find anything. Determine whether this 1714 // was a typo for another field name. 1715 FieldInitializerValidatorCCC Validator(RT->getDecl()); 1716 TypoCorrection Corrected = SemaRef.CorrectTypo( 1717 DeclarationNameInfo(FieldName, D->getFieldLoc()), 1718 Sema::LookupMemberName, /*Scope=*/0, /*SS=*/0, Validator, 1719 RT->getDecl()); 1720 if (Corrected) { 1721 std::string CorrectedStr( 1722 Corrected.getAsString(SemaRef.getLangOpts())); 1723 std::string CorrectedQuotedStr( 1724 Corrected.getQuoted(SemaRef.getLangOpts())); 1725 ReplacementField = Corrected.getCorrectionDeclAs<FieldDecl>(); 1726 SemaRef.Diag(D->getFieldLoc(), 1727 diag::err_field_designator_unknown_suggest) 1728 << FieldName << CurrentObjectType << CorrectedQuotedStr 1729 << FixItHint::CreateReplacement(D->getFieldLoc(), CorrectedStr); 1730 SemaRef.Diag(ReplacementField->getLocation(), 1731 diag::note_previous_decl) << CorrectedQuotedStr; 1732 hadError = true; 1733 } else { 1734 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown) 1735 << FieldName << CurrentObjectType; 1736 ++Index; 1737 return true; 1738 } 1739 } 1740 1741 if (!ReplacementField) { 1742 // Name lookup found something, but it wasn't a field. 1743 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield) 1744 << FieldName; 1745 SemaRef.Diag((*Lookup.first)->getLocation(), 1746 diag::note_field_designator_found); 1747 ++Index; 1748 return true; 1749 } 1750 1751 if (!KnownField) { 1752 // The replacement field comes from typo correction; find it 1753 // in the list of fields. 1754 FieldIndex = 0; 1755 Field = RT->getDecl()->field_begin(); 1756 for (; Field != FieldEnd; ++Field) { 1757 if (Field->isUnnamedBitfield()) 1758 continue; 1759 1760 if (ReplacementField == *Field || 1761 Field->getIdentifier() == ReplacementField->getIdentifier()) 1762 break; 1763 1764 ++FieldIndex; 1765 } 1766 } 1767 } 1768 1769 // All of the fields of a union are located at the same place in 1770 // the initializer list. 1771 if (RT->getDecl()->isUnion()) { 1772 FieldIndex = 0; 1773 if (!VerifyOnly) 1774 StructuredList->setInitializedFieldInUnion(*Field); 1775 } 1776 1777 // Make sure we can use this declaration. 1778 bool InvalidUse; 1779 if (VerifyOnly) 1780 InvalidUse = !SemaRef.CanUseDecl(*Field); 1781 else 1782 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc()); 1783 if (InvalidUse) { 1784 ++Index; 1785 return true; 1786 } 1787 1788 if (!VerifyOnly) { 1789 // Update the designator with the field declaration. 1790 D->setField(*Field); 1791 1792 // Make sure that our non-designated initializer list has space 1793 // for a subobject corresponding to this field. 1794 if (FieldIndex >= StructuredList->getNumInits()) 1795 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1); 1796 } 1797 1798 // This designator names a flexible array member. 1799 if (Field->getType()->isIncompleteArrayType()) { 1800 bool Invalid = false; 1801 if ((DesigIdx + 1) != DIE->size()) { 1802 // We can't designate an object within the flexible array 1803 // member (because GCC doesn't allow it). 1804 if (!VerifyOnly) { 1805 DesignatedInitExpr::Designator *NextD 1806 = DIE->getDesignator(DesigIdx + 1); 1807 SemaRef.Diag(NextD->getStartLocation(), 1808 diag::err_designator_into_flexible_array_member) 1809 << SourceRange(NextD->getStartLocation(), 1810 DIE->getSourceRange().getEnd()); 1811 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1812 << *Field; 1813 } 1814 Invalid = true; 1815 } 1816 1817 if (!hadError && !isa<InitListExpr>(DIE->getInit()) && 1818 !isa<StringLiteral>(DIE->getInit())) { 1819 // The initializer is not an initializer list. 1820 if (!VerifyOnly) { 1821 SemaRef.Diag(DIE->getInit()->getLocStart(), 1822 diag::err_flexible_array_init_needs_braces) 1823 << DIE->getInit()->getSourceRange(); 1824 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1825 << *Field; 1826 } 1827 Invalid = true; 1828 } 1829 1830 // Check GNU flexible array initializer. 1831 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field, 1832 TopLevelObject)) 1833 Invalid = true; 1834 1835 if (Invalid) { 1836 ++Index; 1837 return true; 1838 } 1839 1840 // Initialize the array. 1841 bool prevHadError = hadError; 1842 unsigned newStructuredIndex = FieldIndex; 1843 unsigned OldIndex = Index; 1844 IList->setInit(Index, DIE->getInit()); 1845 1846 InitializedEntity MemberEntity = 1847 InitializedEntity::InitializeMember(*Field, &Entity); 1848 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1849 StructuredList, newStructuredIndex); 1850 1851 IList->setInit(OldIndex, DIE); 1852 if (hadError && !prevHadError) { 1853 ++Field; 1854 ++FieldIndex; 1855 if (NextField) 1856 *NextField = Field; 1857 StructuredIndex = FieldIndex; 1858 return true; 1859 } 1860 } else { 1861 // Recurse to check later designated subobjects. 1862 QualType FieldType = (*Field)->getType(); 1863 unsigned newStructuredIndex = FieldIndex; 1864 1865 InitializedEntity MemberEntity = 1866 InitializedEntity::InitializeMember(*Field, &Entity); 1867 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1, 1868 FieldType, 0, 0, Index, 1869 StructuredList, newStructuredIndex, 1870 true, false)) 1871 return true; 1872 } 1873 1874 // Find the position of the next field to be initialized in this 1875 // subobject. 1876 ++Field; 1877 ++FieldIndex; 1878 1879 // If this the first designator, our caller will continue checking 1880 // the rest of this struct/class/union subobject. 1881 if (IsFirstDesignator) { 1882 if (NextField) 1883 *NextField = Field; 1884 StructuredIndex = FieldIndex; 1885 return false; 1886 } 1887 1888 if (!FinishSubobjectInit) 1889 return false; 1890 1891 // We've already initialized something in the union; we're done. 1892 if (RT->getDecl()->isUnion()) 1893 return hadError; 1894 1895 // Check the remaining fields within this class/struct/union subobject. 1896 bool prevHadError = hadError; 1897 1898 CheckStructUnionTypes(Entity, IList, CurrentObjectType, Field, false, Index, 1899 StructuredList, FieldIndex); 1900 return hadError && !prevHadError; 1901 } 1902 1903 // C99 6.7.8p6: 1904 // 1905 // If a designator has the form 1906 // 1907 // [ constant-expression ] 1908 // 1909 // then the current object (defined below) shall have array 1910 // type and the expression shall be an integer constant 1911 // expression. If the array is of unknown size, any 1912 // nonnegative value is valid. 1913 // 1914 // Additionally, cope with the GNU extension that permits 1915 // designators of the form 1916 // 1917 // [ constant-expression ... constant-expression ] 1918 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType); 1919 if (!AT) { 1920 if (!VerifyOnly) 1921 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array) 1922 << CurrentObjectType; 1923 ++Index; 1924 return true; 1925 } 1926 1927 Expr *IndexExpr = 0; 1928 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex; 1929 if (D->isArrayDesignator()) { 1930 IndexExpr = DIE->getArrayIndex(*D); 1931 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context); 1932 DesignatedEndIndex = DesignatedStartIndex; 1933 } else { 1934 assert(D->isArrayRangeDesignator() && "Need array-range designator"); 1935 1936 DesignatedStartIndex = 1937 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context); 1938 DesignatedEndIndex = 1939 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context); 1940 IndexExpr = DIE->getArrayRangeEnd(*D); 1941 1942 // Codegen can't handle evaluating array range designators that have side 1943 // effects, because we replicate the AST value for each initialized element. 1944 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple 1945 // elements with something that has a side effect, so codegen can emit an 1946 // "error unsupported" error instead of miscompiling the app. 1947 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&& 1948 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly) 1949 FullyStructuredList->sawArrayRangeDesignator(); 1950 } 1951 1952 if (isa<ConstantArrayType>(AT)) { 1953 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false); 1954 DesignatedStartIndex 1955 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth()); 1956 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned()); 1957 DesignatedEndIndex 1958 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth()); 1959 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned()); 1960 if (DesignatedEndIndex >= MaxElements) { 1961 if (!VerifyOnly) 1962 SemaRef.Diag(IndexExpr->getLocStart(), 1963 diag::err_array_designator_too_large) 1964 << DesignatedEndIndex.toString(10) << MaxElements.toString(10) 1965 << IndexExpr->getSourceRange(); 1966 ++Index; 1967 return true; 1968 } 1969 } else { 1970 // Make sure the bit-widths and signedness match. 1971 if (DesignatedStartIndex.getBitWidth() > DesignatedEndIndex.getBitWidth()) 1972 DesignatedEndIndex 1973 = DesignatedEndIndex.extend(DesignatedStartIndex.getBitWidth()); 1974 else if (DesignatedStartIndex.getBitWidth() < 1975 DesignatedEndIndex.getBitWidth()) 1976 DesignatedStartIndex 1977 = DesignatedStartIndex.extend(DesignatedEndIndex.getBitWidth()); 1978 DesignatedStartIndex.setIsUnsigned(true); 1979 DesignatedEndIndex.setIsUnsigned(true); 1980 } 1981 1982 // Make sure that our non-designated initializer list has space 1983 // for a subobject corresponding to this array element. 1984 if (!VerifyOnly && 1985 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits()) 1986 StructuredList->resizeInits(SemaRef.Context, 1987 DesignatedEndIndex.getZExtValue() + 1); 1988 1989 // Repeatedly perform subobject initializations in the range 1990 // [DesignatedStartIndex, DesignatedEndIndex]. 1991 1992 // Move to the next designator 1993 unsigned ElementIndex = DesignatedStartIndex.getZExtValue(); 1994 unsigned OldIndex = Index; 1995 1996 InitializedEntity ElementEntity = 1997 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1998 1999 while (DesignatedStartIndex <= DesignatedEndIndex) { 2000 // Recurse to check later designated subobjects. 2001 QualType ElementType = AT->getElementType(); 2002 Index = OldIndex; 2003 2004 ElementEntity.setElementIndex(ElementIndex); 2005 if (CheckDesignatedInitializer(ElementEntity, IList, DIE, DesigIdx + 1, 2006 ElementType, 0, 0, Index, 2007 StructuredList, ElementIndex, 2008 (DesignatedStartIndex == DesignatedEndIndex), 2009 false)) 2010 return true; 2011 2012 // Move to the next index in the array that we'll be initializing. 2013 ++DesignatedStartIndex; 2014 ElementIndex = DesignatedStartIndex.getZExtValue(); 2015 } 2016 2017 // If this the first designator, our caller will continue checking 2018 // the rest of this array subobject. 2019 if (IsFirstDesignator) { 2020 if (NextElementIndex) 2021 *NextElementIndex = DesignatedStartIndex; 2022 StructuredIndex = ElementIndex; 2023 return false; 2024 } 2025 2026 if (!FinishSubobjectInit) 2027 return false; 2028 2029 // Check the remaining elements within this array subobject. 2030 bool prevHadError = hadError; 2031 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex, 2032 /*SubobjectIsDesignatorContext=*/false, Index, 2033 StructuredList, ElementIndex); 2034 return hadError && !prevHadError; 2035 } 2036 2037 // Get the structured initializer list for a subobject of type 2038 // @p CurrentObjectType. 2039 InitListExpr * 2040 InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 2041 QualType CurrentObjectType, 2042 InitListExpr *StructuredList, 2043 unsigned StructuredIndex, 2044 SourceRange InitRange) { 2045 if (VerifyOnly) 2046 return 0; // No structured list in verification-only mode. 2047 Expr *ExistingInit = 0; 2048 if (!StructuredList) 2049 ExistingInit = SyntacticToSemantic.lookup(IList); 2050 else if (StructuredIndex < StructuredList->getNumInits()) 2051 ExistingInit = StructuredList->getInit(StructuredIndex); 2052 2053 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit)) 2054 return Result; 2055 2056 if (ExistingInit) { 2057 // We are creating an initializer list that initializes the 2058 // subobjects of the current object, but there was already an 2059 // initialization that completely initialized the current 2060 // subobject, e.g., by a compound literal: 2061 // 2062 // struct X { int a, b; }; 2063 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 }; 2064 // 2065 // Here, xs[0].a == 0 and xs[0].b == 3, since the second, 2066 // designated initializer re-initializes the whole 2067 // subobject [0], overwriting previous initializers. 2068 SemaRef.Diag(InitRange.getBegin(), 2069 diag::warn_subobject_initializer_overrides) 2070 << InitRange; 2071 SemaRef.Diag(ExistingInit->getLocStart(), 2072 diag::note_previous_initializer) 2073 << /*FIXME:has side effects=*/0 2074 << ExistingInit->getSourceRange(); 2075 } 2076 2077 InitListExpr *Result 2078 = new (SemaRef.Context) InitListExpr(SemaRef.Context, 2079 InitRange.getBegin(), 0, 0, 2080 InitRange.getEnd()); 2081 2082 QualType ResultType = CurrentObjectType; 2083 if (!ResultType->isArrayType()) 2084 ResultType = ResultType.getNonLValueExprType(SemaRef.Context); 2085 Result->setType(ResultType); 2086 2087 // Pre-allocate storage for the structured initializer list. 2088 unsigned NumElements = 0; 2089 unsigned NumInits = 0; 2090 bool GotNumInits = false; 2091 if (!StructuredList) { 2092 NumInits = IList->getNumInits(); 2093 GotNumInits = true; 2094 } else if (Index < IList->getNumInits()) { 2095 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) { 2096 NumInits = SubList->getNumInits(); 2097 GotNumInits = true; 2098 } 2099 } 2100 2101 if (const ArrayType *AType 2102 = SemaRef.Context.getAsArrayType(CurrentObjectType)) { 2103 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) { 2104 NumElements = CAType->getSize().getZExtValue(); 2105 // Simple heuristic so that we don't allocate a very large 2106 // initializer with many empty entries at the end. 2107 if (GotNumInits && NumElements > NumInits) 2108 NumElements = 0; 2109 } 2110 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>()) 2111 NumElements = VType->getNumElements(); 2112 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) { 2113 RecordDecl *RDecl = RType->getDecl(); 2114 if (RDecl->isUnion()) 2115 NumElements = 1; 2116 else 2117 NumElements = std::distance(RDecl->field_begin(), 2118 RDecl->field_end()); 2119 } 2120 2121 Result->reserveInits(SemaRef.Context, NumElements); 2122 2123 // Link this new initializer list into the structured initializer 2124 // lists. 2125 if (StructuredList) 2126 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result); 2127 else { 2128 Result->setSyntacticForm(IList); 2129 SyntacticToSemantic[IList] = Result; 2130 } 2131 2132 return Result; 2133 } 2134 2135 /// Update the initializer at index @p StructuredIndex within the 2136 /// structured initializer list to the value @p expr. 2137 void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList, 2138 unsigned &StructuredIndex, 2139 Expr *expr) { 2140 // No structured initializer list to update 2141 if (!StructuredList) 2142 return; 2143 2144 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context, 2145 StructuredIndex, expr)) { 2146 // This initializer overwrites a previous initializer. Warn. 2147 SemaRef.Diag(expr->getLocStart(), 2148 diag::warn_initializer_overrides) 2149 << expr->getSourceRange(); 2150 SemaRef.Diag(PrevInit->getLocStart(), 2151 diag::note_previous_initializer) 2152 << /*FIXME:has side effects=*/0 2153 << PrevInit->getSourceRange(); 2154 } 2155 2156 ++StructuredIndex; 2157 } 2158 2159 /// Check that the given Index expression is a valid array designator 2160 /// value. This is essentially just a wrapper around 2161 /// VerifyIntegerConstantExpression that also checks for negative values 2162 /// and produces a reasonable diagnostic if there is a 2163 /// failure. Returns the index expression, possibly with an implicit cast 2164 /// added, on success. If everything went okay, Value will receive the 2165 /// value of the constant expression. 2166 static ExprResult 2167 CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) { 2168 SourceLocation Loc = Index->getLocStart(); 2169 2170 // Make sure this is an integer constant expression. 2171 ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value); 2172 if (Result.isInvalid()) 2173 return Result; 2174 2175 if (Value.isSigned() && Value.isNegative()) 2176 return S.Diag(Loc, diag::err_array_designator_negative) 2177 << Value.toString(10) << Index->getSourceRange(); 2178 2179 Value.setIsUnsigned(true); 2180 return Result; 2181 } 2182 2183 ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig, 2184 SourceLocation Loc, 2185 bool GNUSyntax, 2186 ExprResult Init) { 2187 typedef DesignatedInitExpr::Designator ASTDesignator; 2188 2189 bool Invalid = false; 2190 SmallVector<ASTDesignator, 32> Designators; 2191 SmallVector<Expr *, 32> InitExpressions; 2192 2193 // Build designators and check array designator expressions. 2194 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) { 2195 const Designator &D = Desig.getDesignator(Idx); 2196 switch (D.getKind()) { 2197 case Designator::FieldDesignator: 2198 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(), 2199 D.getFieldLoc())); 2200 break; 2201 2202 case Designator::ArrayDesignator: { 2203 Expr *Index = static_cast<Expr *>(D.getArrayIndex()); 2204 llvm::APSInt IndexValue; 2205 if (!Index->isTypeDependent() && !Index->isValueDependent()) 2206 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).take(); 2207 if (!Index) 2208 Invalid = true; 2209 else { 2210 Designators.push_back(ASTDesignator(InitExpressions.size(), 2211 D.getLBracketLoc(), 2212 D.getRBracketLoc())); 2213 InitExpressions.push_back(Index); 2214 } 2215 break; 2216 } 2217 2218 case Designator::ArrayRangeDesignator: { 2219 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart()); 2220 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd()); 2221 llvm::APSInt StartValue; 2222 llvm::APSInt EndValue; 2223 bool StartDependent = StartIndex->isTypeDependent() || 2224 StartIndex->isValueDependent(); 2225 bool EndDependent = EndIndex->isTypeDependent() || 2226 EndIndex->isValueDependent(); 2227 if (!StartDependent) 2228 StartIndex = 2229 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).take(); 2230 if (!EndDependent) 2231 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).take(); 2232 2233 if (!StartIndex || !EndIndex) 2234 Invalid = true; 2235 else { 2236 // Make sure we're comparing values with the same bit width. 2237 if (StartDependent || EndDependent) { 2238 // Nothing to compute. 2239 } else if (StartValue.getBitWidth() > EndValue.getBitWidth()) 2240 EndValue = EndValue.extend(StartValue.getBitWidth()); 2241 else if (StartValue.getBitWidth() < EndValue.getBitWidth()) 2242 StartValue = StartValue.extend(EndValue.getBitWidth()); 2243 2244 if (!StartDependent && !EndDependent && EndValue < StartValue) { 2245 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range) 2246 << StartValue.toString(10) << EndValue.toString(10) 2247 << StartIndex->getSourceRange() << EndIndex->getSourceRange(); 2248 Invalid = true; 2249 } else { 2250 Designators.push_back(ASTDesignator(InitExpressions.size(), 2251 D.getLBracketLoc(), 2252 D.getEllipsisLoc(), 2253 D.getRBracketLoc())); 2254 InitExpressions.push_back(StartIndex); 2255 InitExpressions.push_back(EndIndex); 2256 } 2257 } 2258 break; 2259 } 2260 } 2261 } 2262 2263 if (Invalid || Init.isInvalid()) 2264 return ExprError(); 2265 2266 // Clear out the expressions within the designation. 2267 Desig.ClearExprs(*this); 2268 2269 DesignatedInitExpr *DIE 2270 = DesignatedInitExpr::Create(Context, 2271 Designators.data(), Designators.size(), 2272 InitExpressions.data(), InitExpressions.size(), 2273 Loc, GNUSyntax, Init.takeAs<Expr>()); 2274 2275 if (!getLangOpts().C99) 2276 Diag(DIE->getLocStart(), diag::ext_designated_init) 2277 << DIE->getSourceRange(); 2278 2279 return Owned(DIE); 2280 } 2281 2282 //===----------------------------------------------------------------------===// 2283 // Initialization entity 2284 //===----------------------------------------------------------------------===// 2285 2286 InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index, 2287 const InitializedEntity &Parent) 2288 : Parent(&Parent), Index(Index) 2289 { 2290 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) { 2291 Kind = EK_ArrayElement; 2292 Type = AT->getElementType(); 2293 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) { 2294 Kind = EK_VectorElement; 2295 Type = VT->getElementType(); 2296 } else { 2297 const ComplexType *CT = Parent.getType()->getAs<ComplexType>(); 2298 assert(CT && "Unexpected type"); 2299 Kind = EK_ComplexElement; 2300 Type = CT->getElementType(); 2301 } 2302 } 2303 2304 InitializedEntity InitializedEntity::InitializeBase(ASTContext &Context, 2305 CXXBaseSpecifier *Base, 2306 bool IsInheritedVirtualBase) 2307 { 2308 InitializedEntity Result; 2309 Result.Kind = EK_Base; 2310 Result.Base = reinterpret_cast<uintptr_t>(Base); 2311 if (IsInheritedVirtualBase) 2312 Result.Base |= 0x01; 2313 2314 Result.Type = Base->getType(); 2315 return Result; 2316 } 2317 2318 DeclarationName InitializedEntity::getName() const { 2319 switch (getKind()) { 2320 case EK_Parameter: { 2321 ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1); 2322 return (D ? D->getDeclName() : DeclarationName()); 2323 } 2324 2325 case EK_Variable: 2326 case EK_Member: 2327 return VariableOrMember->getDeclName(); 2328 2329 case EK_LambdaCapture: 2330 return Capture.Var->getDeclName(); 2331 2332 case EK_Result: 2333 case EK_Exception: 2334 case EK_New: 2335 case EK_Temporary: 2336 case EK_Base: 2337 case EK_Delegating: 2338 case EK_ArrayElement: 2339 case EK_VectorElement: 2340 case EK_ComplexElement: 2341 case EK_BlockElement: 2342 return DeclarationName(); 2343 } 2344 2345 llvm_unreachable("Invalid EntityKind!"); 2346 } 2347 2348 DeclaratorDecl *InitializedEntity::getDecl() const { 2349 switch (getKind()) { 2350 case EK_Variable: 2351 case EK_Member: 2352 return VariableOrMember; 2353 2354 case EK_Parameter: 2355 return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1); 2356 2357 case EK_Result: 2358 case EK_Exception: 2359 case EK_New: 2360 case EK_Temporary: 2361 case EK_Base: 2362 case EK_Delegating: 2363 case EK_ArrayElement: 2364 case EK_VectorElement: 2365 case EK_ComplexElement: 2366 case EK_BlockElement: 2367 case EK_LambdaCapture: 2368 return 0; 2369 } 2370 2371 llvm_unreachable("Invalid EntityKind!"); 2372 } 2373 2374 bool InitializedEntity::allowsNRVO() const { 2375 switch (getKind()) { 2376 case EK_Result: 2377 case EK_Exception: 2378 return LocAndNRVO.NRVO; 2379 2380 case EK_Variable: 2381 case EK_Parameter: 2382 case EK_Member: 2383 case EK_New: 2384 case EK_Temporary: 2385 case EK_Base: 2386 case EK_Delegating: 2387 case EK_ArrayElement: 2388 case EK_VectorElement: 2389 case EK_ComplexElement: 2390 case EK_BlockElement: 2391 case EK_LambdaCapture: 2392 break; 2393 } 2394 2395 return false; 2396 } 2397 2398 //===----------------------------------------------------------------------===// 2399 // Initialization sequence 2400 //===----------------------------------------------------------------------===// 2401 2402 void InitializationSequence::Step::Destroy() { 2403 switch (Kind) { 2404 case SK_ResolveAddressOfOverloadedFunction: 2405 case SK_CastDerivedToBaseRValue: 2406 case SK_CastDerivedToBaseXValue: 2407 case SK_CastDerivedToBaseLValue: 2408 case SK_BindReference: 2409 case SK_BindReferenceToTemporary: 2410 case SK_ExtraneousCopyToTemporary: 2411 case SK_UserConversion: 2412 case SK_QualificationConversionRValue: 2413 case SK_QualificationConversionXValue: 2414 case SK_QualificationConversionLValue: 2415 case SK_ListInitialization: 2416 case SK_ListConstructorCall: 2417 case SK_UnwrapInitList: 2418 case SK_RewrapInitList: 2419 case SK_ConstructorInitialization: 2420 case SK_ZeroInitialization: 2421 case SK_CAssignment: 2422 case SK_StringInit: 2423 case SK_ObjCObjectConversion: 2424 case SK_ArrayInit: 2425 case SK_ParenthesizedArrayInit: 2426 case SK_PassByIndirectCopyRestore: 2427 case SK_PassByIndirectRestore: 2428 case SK_ProduceObjCObject: 2429 case SK_StdInitializerList: 2430 break; 2431 2432 case SK_ConversionSequence: 2433 delete ICS; 2434 } 2435 } 2436 2437 bool InitializationSequence::isDirectReferenceBinding() const { 2438 return !Steps.empty() && Steps.back().Kind == SK_BindReference; 2439 } 2440 2441 bool InitializationSequence::isAmbiguous() const { 2442 if (!Failed()) 2443 return false; 2444 2445 switch (getFailureKind()) { 2446 case FK_TooManyInitsForReference: 2447 case FK_ArrayNeedsInitList: 2448 case FK_ArrayNeedsInitListOrStringLiteral: 2449 case FK_AddressOfOverloadFailed: // FIXME: Could do better 2450 case FK_NonConstLValueReferenceBindingToTemporary: 2451 case FK_NonConstLValueReferenceBindingToUnrelated: 2452 case FK_RValueReferenceBindingToLValue: 2453 case FK_ReferenceInitDropsQualifiers: 2454 case FK_ReferenceInitFailed: 2455 case FK_ConversionFailed: 2456 case FK_ConversionFromPropertyFailed: 2457 case FK_TooManyInitsForScalar: 2458 case FK_ReferenceBindingToInitList: 2459 case FK_InitListBadDestinationType: 2460 case FK_DefaultInitOfConst: 2461 case FK_Incomplete: 2462 case FK_ArrayTypeMismatch: 2463 case FK_NonConstantArrayInit: 2464 case FK_ListInitializationFailed: 2465 case FK_VariableLengthArrayHasInitializer: 2466 case FK_PlaceholderType: 2467 case FK_InitListElementCopyFailure: 2468 case FK_ExplicitConstructor: 2469 return false; 2470 2471 case FK_ReferenceInitOverloadFailed: 2472 case FK_UserConversionOverloadFailed: 2473 case FK_ConstructorOverloadFailed: 2474 case FK_ListConstructorOverloadFailed: 2475 return FailedOverloadResult == OR_Ambiguous; 2476 } 2477 2478 llvm_unreachable("Invalid EntityKind!"); 2479 } 2480 2481 bool InitializationSequence::isConstructorInitialization() const { 2482 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization; 2483 } 2484 2485 void 2486 InitializationSequence 2487 ::AddAddressOverloadResolutionStep(FunctionDecl *Function, 2488 DeclAccessPair Found, 2489 bool HadMultipleCandidates) { 2490 Step S; 2491 S.Kind = SK_ResolveAddressOfOverloadedFunction; 2492 S.Type = Function->getType(); 2493 S.Function.HadMultipleCandidates = HadMultipleCandidates; 2494 S.Function.Function = Function; 2495 S.Function.FoundDecl = Found; 2496 Steps.push_back(S); 2497 } 2498 2499 void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType, 2500 ExprValueKind VK) { 2501 Step S; 2502 switch (VK) { 2503 case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break; 2504 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break; 2505 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break; 2506 } 2507 S.Type = BaseType; 2508 Steps.push_back(S); 2509 } 2510 2511 void InitializationSequence::AddReferenceBindingStep(QualType T, 2512 bool BindingTemporary) { 2513 Step S; 2514 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference; 2515 S.Type = T; 2516 Steps.push_back(S); 2517 } 2518 2519 void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) { 2520 Step S; 2521 S.Kind = SK_ExtraneousCopyToTemporary; 2522 S.Type = T; 2523 Steps.push_back(S); 2524 } 2525 2526 void 2527 InitializationSequence::AddUserConversionStep(FunctionDecl *Function, 2528 DeclAccessPair FoundDecl, 2529 QualType T, 2530 bool HadMultipleCandidates) { 2531 Step S; 2532 S.Kind = SK_UserConversion; 2533 S.Type = T; 2534 S.Function.HadMultipleCandidates = HadMultipleCandidates; 2535 S.Function.Function = Function; 2536 S.Function.FoundDecl = FoundDecl; 2537 Steps.push_back(S); 2538 } 2539 2540 void InitializationSequence::AddQualificationConversionStep(QualType Ty, 2541 ExprValueKind VK) { 2542 Step S; 2543 S.Kind = SK_QualificationConversionRValue; // work around a gcc warning 2544 switch (VK) { 2545 case VK_RValue: 2546 S.Kind = SK_QualificationConversionRValue; 2547 break; 2548 case VK_XValue: 2549 S.Kind = SK_QualificationConversionXValue; 2550 break; 2551 case VK_LValue: 2552 S.Kind = SK_QualificationConversionLValue; 2553 break; 2554 } 2555 S.Type = Ty; 2556 Steps.push_back(S); 2557 } 2558 2559 void InitializationSequence::AddConversionSequenceStep( 2560 const ImplicitConversionSequence &ICS, 2561 QualType T) { 2562 Step S; 2563 S.Kind = SK_ConversionSequence; 2564 S.Type = T; 2565 S.ICS = new ImplicitConversionSequence(ICS); 2566 Steps.push_back(S); 2567 } 2568 2569 void InitializationSequence::AddListInitializationStep(QualType T) { 2570 Step S; 2571 S.Kind = SK_ListInitialization; 2572 S.Type = T; 2573 Steps.push_back(S); 2574 } 2575 2576 void 2577 InitializationSequence 2578 ::AddConstructorInitializationStep(CXXConstructorDecl *Constructor, 2579 AccessSpecifier Access, 2580 QualType T, 2581 bool HadMultipleCandidates, 2582 bool FromInitList, bool AsInitList) { 2583 Step S; 2584 S.Kind = FromInitList && !AsInitList ? SK_ListConstructorCall 2585 : SK_ConstructorInitialization; 2586 S.Type = T; 2587 S.Function.HadMultipleCandidates = HadMultipleCandidates; 2588 S.Function.Function = Constructor; 2589 S.Function.FoundDecl = DeclAccessPair::make(Constructor, Access); 2590 Steps.push_back(S); 2591 } 2592 2593 void InitializationSequence::AddZeroInitializationStep(QualType T) { 2594 Step S; 2595 S.Kind = SK_ZeroInitialization; 2596 S.Type = T; 2597 Steps.push_back(S); 2598 } 2599 2600 void InitializationSequence::AddCAssignmentStep(QualType T) { 2601 Step S; 2602 S.Kind = SK_CAssignment; 2603 S.Type = T; 2604 Steps.push_back(S); 2605 } 2606 2607 void InitializationSequence::AddStringInitStep(QualType T) { 2608 Step S; 2609 S.Kind = SK_StringInit; 2610 S.Type = T; 2611 Steps.push_back(S); 2612 } 2613 2614 void InitializationSequence::AddObjCObjectConversionStep(QualType T) { 2615 Step S; 2616 S.Kind = SK_ObjCObjectConversion; 2617 S.Type = T; 2618 Steps.push_back(S); 2619 } 2620 2621 void InitializationSequence::AddArrayInitStep(QualType T) { 2622 Step S; 2623 S.Kind = SK_ArrayInit; 2624 S.Type = T; 2625 Steps.push_back(S); 2626 } 2627 2628 void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) { 2629 Step S; 2630 S.Kind = SK_ParenthesizedArrayInit; 2631 S.Type = T; 2632 Steps.push_back(S); 2633 } 2634 2635 void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type, 2636 bool shouldCopy) { 2637 Step s; 2638 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore 2639 : SK_PassByIndirectRestore); 2640 s.Type = type; 2641 Steps.push_back(s); 2642 } 2643 2644 void InitializationSequence::AddProduceObjCObjectStep(QualType T) { 2645 Step S; 2646 S.Kind = SK_ProduceObjCObject; 2647 S.Type = T; 2648 Steps.push_back(S); 2649 } 2650 2651 void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) { 2652 Step S; 2653 S.Kind = SK_StdInitializerList; 2654 S.Type = T; 2655 Steps.push_back(S); 2656 } 2657 2658 void InitializationSequence::RewrapReferenceInitList(QualType T, 2659 InitListExpr *Syntactic) { 2660 assert(Syntactic->getNumInits() == 1 && 2661 "Can only rewrap trivial init lists."); 2662 Step S; 2663 S.Kind = SK_UnwrapInitList; 2664 S.Type = Syntactic->getInit(0)->getType(); 2665 Steps.insert(Steps.begin(), S); 2666 2667 S.Kind = SK_RewrapInitList; 2668 S.Type = T; 2669 S.WrappingSyntacticList = Syntactic; 2670 Steps.push_back(S); 2671 } 2672 2673 void InitializationSequence::SetOverloadFailure(FailureKind Failure, 2674 OverloadingResult Result) { 2675 setSequenceKind(FailedSequence); 2676 this->Failure = Failure; 2677 this->FailedOverloadResult = Result; 2678 } 2679 2680 //===----------------------------------------------------------------------===// 2681 // Attempt initialization 2682 //===----------------------------------------------------------------------===// 2683 2684 static void MaybeProduceObjCObject(Sema &S, 2685 InitializationSequence &Sequence, 2686 const InitializedEntity &Entity) { 2687 if (!S.getLangOpts().ObjCAutoRefCount) return; 2688 2689 /// When initializing a parameter, produce the value if it's marked 2690 /// __attribute__((ns_consumed)). 2691 if (Entity.getKind() == InitializedEntity::EK_Parameter) { 2692 if (!Entity.isParameterConsumed()) 2693 return; 2694 2695 assert(Entity.getType()->isObjCRetainableType() && 2696 "consuming an object of unretainable type?"); 2697 Sequence.AddProduceObjCObjectStep(Entity.getType()); 2698 2699 /// When initializing a return value, if the return type is a 2700 /// retainable type, then returns need to immediately retain the 2701 /// object. If an autorelease is required, it will be done at the 2702 /// last instant. 2703 } else if (Entity.getKind() == InitializedEntity::EK_Result) { 2704 if (!Entity.getType()->isObjCRetainableType()) 2705 return; 2706 2707 Sequence.AddProduceObjCObjectStep(Entity.getType()); 2708 } 2709 } 2710 2711 /// \brief When initializing from init list via constructor, deal with the 2712 /// empty init list and std::initializer_list special cases. 2713 /// 2714 /// \return True if this was a special case, false otherwise. 2715 static bool TryListConstructionSpecialCases(Sema &S, 2716 InitListExpr *List, 2717 CXXRecordDecl *DestRecordDecl, 2718 QualType DestType, 2719 InitializationSequence &Sequence) { 2720 // C++11 [dcl.init.list]p3: 2721 // List-initialization of an object or reference of type T is defined as 2722 // follows: 2723 // - If T is an aggregate, aggregate initialization is performed. 2724 if (DestType->isAggregateType()) 2725 return false; 2726 2727 // - Otherwise, if the initializer list has no elements and T is a class 2728 // type with a default constructor, the object is value-initialized. 2729 if (List->getNumInits() == 0) { 2730 if (CXXConstructorDecl *DefaultConstructor = 2731 S.LookupDefaultConstructor(DestRecordDecl)) { 2732 if (DefaultConstructor->isDeleted() || 2733 S.isFunctionConsideredUnavailable(DefaultConstructor)) { 2734 // Fake an overload resolution failure. 2735 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2736 DeclAccessPair FoundDecl = DeclAccessPair::make(DefaultConstructor, 2737 DefaultConstructor->getAccess()); 2738 if (FunctionTemplateDecl *ConstructorTmpl = 2739 dyn_cast<FunctionTemplateDecl>(DefaultConstructor)) 2740 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2741 /*ExplicitArgs*/ 0, 2742 ArrayRef<Expr*>(), CandidateSet, 2743 /*SuppressUserConversions*/ false); 2744 else 2745 S.AddOverloadCandidate(DefaultConstructor, FoundDecl, 2746 ArrayRef<Expr*>(), CandidateSet, 2747 /*SuppressUserConversions*/ false); 2748 Sequence.SetOverloadFailure( 2749 InitializationSequence::FK_ListConstructorOverloadFailed, 2750 OR_Deleted); 2751 } else 2752 Sequence.AddConstructorInitializationStep(DefaultConstructor, 2753 DefaultConstructor->getAccess(), 2754 DestType, 2755 /*MultipleCandidates=*/false, 2756 /*FromInitList=*/true, 2757 /*AsInitList=*/false); 2758 return true; 2759 } 2760 } 2761 2762 // - Otherwise, if T is a specialization of std::initializer_list, [...] 2763 QualType E; 2764 if (S.isStdInitializerList(DestType, &E)) { 2765 // Check that each individual element can be copy-constructed. But since we 2766 // have no place to store further information, we'll recalculate everything 2767 // later. 2768 InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( 2769 S.Context.getConstantArrayType(E, 2770 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), 2771 List->getNumInits()), 2772 ArrayType::Normal, 0)); 2773 InitializedEntity Element = InitializedEntity::InitializeElement(S.Context, 2774 0, HiddenArray); 2775 for (unsigned i = 0, n = List->getNumInits(); i < n; ++i) { 2776 Element.setElementIndex(i); 2777 if (!S.CanPerformCopyInitialization(Element, List->getInit(i))) { 2778 Sequence.SetFailed( 2779 InitializationSequence::FK_InitListElementCopyFailure); 2780 return true; 2781 } 2782 } 2783 Sequence.AddStdInitializerListConstructionStep(DestType); 2784 return true; 2785 } 2786 2787 // Not a special case. 2788 return false; 2789 } 2790 2791 static OverloadingResult 2792 ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc, 2793 Expr **Args, unsigned NumArgs, 2794 OverloadCandidateSet &CandidateSet, 2795 DeclContext::lookup_iterator Con, 2796 DeclContext::lookup_iterator ConEnd, 2797 OverloadCandidateSet::iterator &Best, 2798 bool CopyInitializing, bool AllowExplicit, 2799 bool OnlyListConstructors, bool InitListSyntax) { 2800 CandidateSet.clear(); 2801 2802 for (; Con != ConEnd; ++Con) { 2803 NamedDecl *D = *Con; 2804 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2805 bool SuppressUserConversions = false; 2806 2807 // Find the constructor (which may be a template). 2808 CXXConstructorDecl *Constructor = 0; 2809 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 2810 if (ConstructorTmpl) 2811 Constructor = cast<CXXConstructorDecl>( 2812 ConstructorTmpl->getTemplatedDecl()); 2813 else { 2814 Constructor = cast<CXXConstructorDecl>(D); 2815 2816 // If we're performing copy initialization using a copy constructor, we 2817 // suppress user-defined conversions on the arguments. We do the same for 2818 // move constructors. 2819 if ((CopyInitializing || (InitListSyntax && NumArgs == 1)) && 2820 Constructor->isCopyOrMoveConstructor()) 2821 SuppressUserConversions = true; 2822 } 2823 2824 if (!Constructor->isInvalidDecl() && 2825 (AllowExplicit || !Constructor->isExplicit()) && 2826 (!OnlyListConstructors || S.isInitListConstructor(Constructor))) { 2827 if (ConstructorTmpl) 2828 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2829 /*ExplicitArgs*/ 0, 2830 llvm::makeArrayRef(Args, NumArgs), 2831 CandidateSet, SuppressUserConversions); 2832 else { 2833 // C++ [over.match.copy]p1: 2834 // - When initializing a temporary to be bound to the first parameter 2835 // of a constructor that takes a reference to possibly cv-qualified 2836 // T as its first argument, called with a single argument in the 2837 // context of direct-initialization, explicit conversion functions 2838 // are also considered. 2839 bool AllowExplicitConv = AllowExplicit && !CopyInitializing && 2840 NumArgs == 1 && 2841 Constructor->isCopyOrMoveConstructor(); 2842 S.AddOverloadCandidate(Constructor, FoundDecl, 2843 llvm::makeArrayRef(Args, NumArgs), CandidateSet, 2844 SuppressUserConversions, 2845 /*PartialOverloading=*/false, 2846 /*AllowExplicit=*/AllowExplicitConv); 2847 } 2848 } 2849 } 2850 2851 // Perform overload resolution and return the result. 2852 return CandidateSet.BestViableFunction(S, DeclLoc, Best); 2853 } 2854 2855 /// \brief Attempt initialization by constructor (C++ [dcl.init]), which 2856 /// enumerates the constructors of the initialized entity and performs overload 2857 /// resolution to select the best. 2858 /// If InitListSyntax is true, this is list-initialization of a non-aggregate 2859 /// class type. 2860 static void TryConstructorInitialization(Sema &S, 2861 const InitializedEntity &Entity, 2862 const InitializationKind &Kind, 2863 Expr **Args, unsigned NumArgs, 2864 QualType DestType, 2865 InitializationSequence &Sequence, 2866 bool InitListSyntax = false) { 2867 assert((!InitListSyntax || (NumArgs == 1 && isa<InitListExpr>(Args[0]))) && 2868 "InitListSyntax must come with a single initializer list argument."); 2869 2870 // Check constructor arguments for self reference. 2871 if (DeclaratorDecl *DD = Entity.getDecl()) 2872 // Parameters arguments are occassionially constructed with itself, 2873 // for instance, in recursive functions. Skip them. 2874 if (!isa<ParmVarDecl>(DD)) 2875 for (unsigned i = 0; i < NumArgs; ++i) 2876 S.CheckSelfReference(DD, Args[i]); 2877 2878 // The type we're constructing needs to be complete. 2879 if (S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { 2880 Sequence.setIncompleteTypeFailure(DestType); 2881 return; 2882 } 2883 2884 const RecordType *DestRecordType = DestType->getAs<RecordType>(); 2885 assert(DestRecordType && "Constructor initialization requires record type"); 2886 CXXRecordDecl *DestRecordDecl 2887 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 2888 2889 if (InitListSyntax && 2890 TryListConstructionSpecialCases(S, cast<InitListExpr>(Args[0]), 2891 DestRecordDecl, DestType, Sequence)) 2892 return; 2893 2894 // Build the candidate set directly in the initialization sequence 2895 // structure, so that it will persist if we fail. 2896 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2897 2898 // Determine whether we are allowed to call explicit constructors or 2899 // explicit conversion operators. 2900 bool AllowExplicit = Kind.AllowExplicit() || InitListSyntax; 2901 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy; 2902 2903 // - Otherwise, if T is a class type, constructors are considered. The 2904 // applicable constructors are enumerated, and the best one is chosen 2905 // through overload resolution. 2906 DeclContext::lookup_iterator ConStart, ConEnd; 2907 llvm::tie(ConStart, ConEnd) = S.LookupConstructors(DestRecordDecl); 2908 2909 OverloadingResult Result = OR_No_Viable_Function; 2910 OverloadCandidateSet::iterator Best; 2911 bool AsInitializerList = false; 2912 2913 // C++11 [over.match.list]p1: 2914 // When objects of non-aggregate type T are list-initialized, overload 2915 // resolution selects the constructor in two phases: 2916 // - Initially, the candidate functions are the initializer-list 2917 // constructors of the class T and the argument list consists of the 2918 // initializer list as a single argument. 2919 if (InitListSyntax) { 2920 AsInitializerList = true; 2921 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args, NumArgs, 2922 CandidateSet, ConStart, ConEnd, Best, 2923 CopyInitialization, AllowExplicit, 2924 /*OnlyListConstructor=*/true, 2925 InitListSyntax); 2926 2927 // Time to unwrap the init list. 2928 InitListExpr *ILE = cast<InitListExpr>(Args[0]); 2929 Args = ILE->getInits(); 2930 NumArgs = ILE->getNumInits(); 2931 } 2932 2933 // C++11 [over.match.list]p1: 2934 // - If no viable initializer-list constructor is found, overload resolution 2935 // is performed again, where the candidate functions are all the 2936 // constructors of the class T nad the argument list consists of the 2937 // elements of the initializer list. 2938 if (Result == OR_No_Viable_Function) { 2939 AsInitializerList = false; 2940 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args, NumArgs, 2941 CandidateSet, ConStart, ConEnd, Best, 2942 CopyInitialization, AllowExplicit, 2943 /*OnlyListConstructors=*/false, 2944 InitListSyntax); 2945 } 2946 if (Result) { 2947 Sequence.SetOverloadFailure(InitListSyntax ? 2948 InitializationSequence::FK_ListConstructorOverloadFailed : 2949 InitializationSequence::FK_ConstructorOverloadFailed, 2950 Result); 2951 return; 2952 } 2953 2954 // C++0x [dcl.init]p6: 2955 // If a program calls for the default initialization of an object 2956 // of a const-qualified type T, T shall be a class type with a 2957 // user-provided default constructor. 2958 if (Kind.getKind() == InitializationKind::IK_Default && 2959 Entity.getType().isConstQualified() && 2960 cast<CXXConstructorDecl>(Best->Function)->isImplicit()) { 2961 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 2962 return; 2963 } 2964 2965 // C++11 [over.match.list]p1: 2966 // In copy-list-initialization, if an explicit constructor is chosen, the 2967 // initializer is ill-formed. 2968 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function); 2969 if (InitListSyntax && !Kind.AllowExplicit() && CtorDecl->isExplicit()) { 2970 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor); 2971 return; 2972 } 2973 2974 // Add the constructor initialization step. Any cv-qualification conversion is 2975 // subsumed by the initialization. 2976 bool HadMultipleCandidates = (CandidateSet.size() > 1); 2977 Sequence.AddConstructorInitializationStep(CtorDecl, 2978 Best->FoundDecl.getAccess(), 2979 DestType, HadMultipleCandidates, 2980 InitListSyntax, AsInitializerList); 2981 } 2982 2983 static bool 2984 ResolveOverloadedFunctionForReferenceBinding(Sema &S, 2985 Expr *Initializer, 2986 QualType &SourceType, 2987 QualType &UnqualifiedSourceType, 2988 QualType UnqualifiedTargetType, 2989 InitializationSequence &Sequence) { 2990 if (S.Context.getCanonicalType(UnqualifiedSourceType) == 2991 S.Context.OverloadTy) { 2992 DeclAccessPair Found; 2993 bool HadMultipleCandidates = false; 2994 if (FunctionDecl *Fn 2995 = S.ResolveAddressOfOverloadedFunction(Initializer, 2996 UnqualifiedTargetType, 2997 false, Found, 2998 &HadMultipleCandidates)) { 2999 Sequence.AddAddressOverloadResolutionStep(Fn, Found, 3000 HadMultipleCandidates); 3001 SourceType = Fn->getType(); 3002 UnqualifiedSourceType = SourceType.getUnqualifiedType(); 3003 } else if (!UnqualifiedTargetType->isRecordType()) { 3004 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 3005 return true; 3006 } 3007 } 3008 return false; 3009 } 3010 3011 static void TryReferenceInitializationCore(Sema &S, 3012 const InitializedEntity &Entity, 3013 const InitializationKind &Kind, 3014 Expr *Initializer, 3015 QualType cv1T1, QualType T1, 3016 Qualifiers T1Quals, 3017 QualType cv2T2, QualType T2, 3018 Qualifiers T2Quals, 3019 InitializationSequence &Sequence); 3020 3021 static void TryListInitialization(Sema &S, 3022 const InitializedEntity &Entity, 3023 const InitializationKind &Kind, 3024 InitListExpr *InitList, 3025 InitializationSequence &Sequence); 3026 3027 /// \brief Attempt list initialization of a reference. 3028 static void TryReferenceListInitialization(Sema &S, 3029 const InitializedEntity &Entity, 3030 const InitializationKind &Kind, 3031 InitListExpr *InitList, 3032 InitializationSequence &Sequence) 3033 { 3034 // First, catch C++03 where this isn't possible. 3035 if (!S.getLangOpts().CPlusPlus0x) { 3036 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList); 3037 return; 3038 } 3039 3040 QualType DestType = Entity.getType(); 3041 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 3042 Qualifiers T1Quals; 3043 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); 3044 3045 // Reference initialization via an initializer list works thus: 3046 // If the initializer list consists of a single element that is 3047 // reference-related to the referenced type, bind directly to that element 3048 // (possibly creating temporaries). 3049 // Otherwise, initialize a temporary with the initializer list and 3050 // bind to that. 3051 if (InitList->getNumInits() == 1) { 3052 Expr *Initializer = InitList->getInit(0); 3053 QualType cv2T2 = Initializer->getType(); 3054 Qualifiers T2Quals; 3055 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); 3056 3057 // If this fails, creating a temporary wouldn't work either. 3058 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2, 3059 T1, Sequence)) 3060 return; 3061 3062 SourceLocation DeclLoc = Initializer->getLocStart(); 3063 bool dummy1, dummy2, dummy3; 3064 Sema::ReferenceCompareResult RefRelationship 3065 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1, 3066 dummy2, dummy3); 3067 if (RefRelationship >= Sema::Ref_Related) { 3068 // Try to bind the reference here. 3069 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1, 3070 T1Quals, cv2T2, T2, T2Quals, Sequence); 3071 if (Sequence) 3072 Sequence.RewrapReferenceInitList(cv1T1, InitList); 3073 return; 3074 } 3075 } 3076 3077 // Not reference-related. Create a temporary and bind to that. 3078 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); 3079 3080 TryListInitialization(S, TempEntity, Kind, InitList, Sequence); 3081 if (Sequence) { 3082 if (DestType->isRValueReferenceType() || 3083 (T1Quals.hasConst() && !T1Quals.hasVolatile())) 3084 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 3085 else 3086 Sequence.SetFailed( 3087 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); 3088 } 3089 } 3090 3091 /// \brief Attempt list initialization (C++0x [dcl.init.list]) 3092 static void TryListInitialization(Sema &S, 3093 const InitializedEntity &Entity, 3094 const InitializationKind &Kind, 3095 InitListExpr *InitList, 3096 InitializationSequence &Sequence) { 3097 QualType DestType = Entity.getType(); 3098 3099 // C++ doesn't allow scalar initialization with more than one argument. 3100 // But C99 complex numbers are scalars and it makes sense there. 3101 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() && 3102 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) { 3103 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar); 3104 return; 3105 } 3106 if (DestType->isReferenceType()) { 3107 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence); 3108 return; 3109 } 3110 if (DestType->isRecordType()) { 3111 if (S.RequireCompleteType(InitList->getLocStart(), DestType, S.PDiag())) { 3112 Sequence.setIncompleteTypeFailure(DestType); 3113 return; 3114 } 3115 3116 if (!DestType->isAggregateType()) { 3117 if (S.getLangOpts().CPlusPlus0x) { 3118 Expr *Arg = InitList; 3119 // A direct-initializer is not list-syntax, i.e. there's no special 3120 // treatment of "A a({1, 2});". 3121 TryConstructorInitialization(S, Entity, Kind, &Arg, 1, DestType, 3122 Sequence, 3123 Kind.getKind() != InitializationKind::IK_Direct); 3124 } else 3125 Sequence.SetFailed( 3126 InitializationSequence::FK_InitListBadDestinationType); 3127 return; 3128 } 3129 } 3130 3131 InitListChecker CheckInitList(S, Entity, InitList, 3132 DestType, /*VerifyOnly=*/true, 3133 Kind.getKind() != InitializationKind::IK_DirectList || 3134 !S.getLangOpts().CPlusPlus0x); 3135 if (CheckInitList.HadError()) { 3136 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed); 3137 return; 3138 } 3139 3140 // Add the list initialization step with the built init list. 3141 Sequence.AddListInitializationStep(DestType); 3142 } 3143 3144 /// \brief Try a reference initialization that involves calling a conversion 3145 /// function. 3146 static OverloadingResult TryRefInitWithConversionFunction(Sema &S, 3147 const InitializedEntity &Entity, 3148 const InitializationKind &Kind, 3149 Expr *Initializer, 3150 bool AllowRValues, 3151 InitializationSequence &Sequence) { 3152 QualType DestType = Entity.getType(); 3153 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 3154 QualType T1 = cv1T1.getUnqualifiedType(); 3155 QualType cv2T2 = Initializer->getType(); 3156 QualType T2 = cv2T2.getUnqualifiedType(); 3157 3158 bool DerivedToBase; 3159 bool ObjCConversion; 3160 bool ObjCLifetimeConversion; 3161 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(), 3162 T1, T2, DerivedToBase, 3163 ObjCConversion, 3164 ObjCLifetimeConversion) && 3165 "Must have incompatible references when binding via conversion"); 3166 (void)DerivedToBase; 3167 (void)ObjCConversion; 3168 (void)ObjCLifetimeConversion; 3169 3170 // Build the candidate set directly in the initialization sequence 3171 // structure, so that it will persist if we fail. 3172 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 3173 CandidateSet.clear(); 3174 3175 // Determine whether we are allowed to call explicit constructors or 3176 // explicit conversion operators. 3177 bool AllowExplicit = Kind.AllowExplicit(); 3178 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctions(); 3179 3180 const RecordType *T1RecordType = 0; 3181 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) && 3182 !S.RequireCompleteType(Kind.getLocation(), T1, 0)) { 3183 // The type we're converting to is a class type. Enumerate its constructors 3184 // to see if there is a suitable conversion. 3185 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl()); 3186 3187 DeclContext::lookup_iterator Con, ConEnd; 3188 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(T1RecordDecl); 3189 Con != ConEnd; ++Con) { 3190 NamedDecl *D = *Con; 3191 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 3192 3193 // Find the constructor (which may be a template). 3194 CXXConstructorDecl *Constructor = 0; 3195 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 3196 if (ConstructorTmpl) 3197 Constructor = cast<CXXConstructorDecl>( 3198 ConstructorTmpl->getTemplatedDecl()); 3199 else 3200 Constructor = cast<CXXConstructorDecl>(D); 3201 3202 if (!Constructor->isInvalidDecl() && 3203 Constructor->isConvertingConstructor(AllowExplicit)) { 3204 if (ConstructorTmpl) 3205 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 3206 /*ExplicitArgs*/ 0, 3207 Initializer, CandidateSet, 3208 /*SuppressUserConversions=*/true); 3209 else 3210 S.AddOverloadCandidate(Constructor, FoundDecl, 3211 Initializer, CandidateSet, 3212 /*SuppressUserConversions=*/true); 3213 } 3214 } 3215 } 3216 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl()) 3217 return OR_No_Viable_Function; 3218 3219 const RecordType *T2RecordType = 0; 3220 if ((T2RecordType = T2->getAs<RecordType>()) && 3221 !S.RequireCompleteType(Kind.getLocation(), T2, 0)) { 3222 // The type we're converting from is a class type, enumerate its conversion 3223 // functions. 3224 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl()); 3225 3226 const UnresolvedSetImpl *Conversions 3227 = T2RecordDecl->getVisibleConversionFunctions(); 3228 for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), 3229 E = Conversions->end(); I != E; ++I) { 3230 NamedDecl *D = *I; 3231 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3232 if (isa<UsingShadowDecl>(D)) 3233 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3234 3235 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 3236 CXXConversionDecl *Conv; 3237 if (ConvTemplate) 3238 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3239 else 3240 Conv = cast<CXXConversionDecl>(D); 3241 3242 // If the conversion function doesn't return a reference type, 3243 // it can't be considered for this conversion unless we're allowed to 3244 // consider rvalues. 3245 // FIXME: Do we need to make sure that we only consider conversion 3246 // candidates with reference-compatible results? That might be needed to 3247 // break recursion. 3248 if ((AllowExplicitConvs || !Conv->isExplicit()) && 3249 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){ 3250 if (ConvTemplate) 3251 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 3252 ActingDC, Initializer, 3253 DestType, CandidateSet); 3254 else 3255 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 3256 Initializer, DestType, CandidateSet); 3257 } 3258 } 3259 } 3260 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl()) 3261 return OR_No_Viable_Function; 3262 3263 SourceLocation DeclLoc = Initializer->getLocStart(); 3264 3265 // Perform overload resolution. If it fails, return the failed result. 3266 OverloadCandidateSet::iterator Best; 3267 if (OverloadingResult Result 3268 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) 3269 return Result; 3270 3271 FunctionDecl *Function = Best->Function; 3272 3273 // This is the overload that will actually be used for the initialization, so 3274 // mark it as used. 3275 S.MarkFunctionReferenced(DeclLoc, Function); 3276 3277 // Compute the returned type of the conversion. 3278 if (isa<CXXConversionDecl>(Function)) 3279 T2 = Function->getResultType(); 3280 else 3281 T2 = cv1T1; 3282 3283 // Add the user-defined conversion step. 3284 bool HadMultipleCandidates = (CandidateSet.size() > 1); 3285 Sequence.AddUserConversionStep(Function, Best->FoundDecl, 3286 T2.getNonLValueExprType(S.Context), 3287 HadMultipleCandidates); 3288 3289 // Determine whether we need to perform derived-to-base or 3290 // cv-qualification adjustments. 3291 ExprValueKind VK = VK_RValue; 3292 if (T2->isLValueReferenceType()) 3293 VK = VK_LValue; 3294 else if (const RValueReferenceType *RRef = T2->getAs<RValueReferenceType>()) 3295 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue; 3296 3297 bool NewDerivedToBase = false; 3298 bool NewObjCConversion = false; 3299 bool NewObjCLifetimeConversion = false; 3300 Sema::ReferenceCompareResult NewRefRelationship 3301 = S.CompareReferenceRelationship(DeclLoc, T1, 3302 T2.getNonLValueExprType(S.Context), 3303 NewDerivedToBase, NewObjCConversion, 3304 NewObjCLifetimeConversion); 3305 if (NewRefRelationship == Sema::Ref_Incompatible) { 3306 // If the type we've converted to is not reference-related to the 3307 // type we're looking for, then there is another conversion step 3308 // we need to perform to produce a temporary of the right type 3309 // that we'll be binding to. 3310 ImplicitConversionSequence ICS; 3311 ICS.setStandard(); 3312 ICS.Standard = Best->FinalConversion; 3313 T2 = ICS.Standard.getToType(2); 3314 Sequence.AddConversionSequenceStep(ICS, T2); 3315 } else if (NewDerivedToBase) 3316 Sequence.AddDerivedToBaseCastStep( 3317 S.Context.getQualifiedType(T1, 3318 T2.getNonReferenceType().getQualifiers()), 3319 VK); 3320 else if (NewObjCConversion) 3321 Sequence.AddObjCObjectConversionStep( 3322 S.Context.getQualifiedType(T1, 3323 T2.getNonReferenceType().getQualifiers())); 3324 3325 if (cv1T1.getQualifiers() != T2.getNonReferenceType().getQualifiers()) 3326 Sequence.AddQualificationConversionStep(cv1T1, VK); 3327 3328 Sequence.AddReferenceBindingStep(cv1T1, !T2->isReferenceType()); 3329 return OR_Success; 3330 } 3331 3332 static void CheckCXX98CompatAccessibleCopy(Sema &S, 3333 const InitializedEntity &Entity, 3334 Expr *CurInitExpr); 3335 3336 /// \brief Attempt reference initialization (C++0x [dcl.init.ref]) 3337 static void TryReferenceInitialization(Sema &S, 3338 const InitializedEntity &Entity, 3339 const InitializationKind &Kind, 3340 Expr *Initializer, 3341 InitializationSequence &Sequence) { 3342 QualType DestType = Entity.getType(); 3343 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 3344 Qualifiers T1Quals; 3345 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); 3346 QualType cv2T2 = Initializer->getType(); 3347 Qualifiers T2Quals; 3348 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); 3349 3350 // If the initializer is the address of an overloaded function, try 3351 // to resolve the overloaded function. If all goes well, T2 is the 3352 // type of the resulting function. 3353 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2, 3354 T1, Sequence)) 3355 return; 3356 3357 // Delegate everything else to a subfunction. 3358 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1, 3359 T1Quals, cv2T2, T2, T2Quals, Sequence); 3360 } 3361 3362 /// \brief Reference initialization without resolving overloaded functions. 3363 static void TryReferenceInitializationCore(Sema &S, 3364 const InitializedEntity &Entity, 3365 const InitializationKind &Kind, 3366 Expr *Initializer, 3367 QualType cv1T1, QualType T1, 3368 Qualifiers T1Quals, 3369 QualType cv2T2, QualType T2, 3370 Qualifiers T2Quals, 3371 InitializationSequence &Sequence) { 3372 QualType DestType = Entity.getType(); 3373 SourceLocation DeclLoc = Initializer->getLocStart(); 3374 // Compute some basic properties of the types and the initializer. 3375 bool isLValueRef = DestType->isLValueReferenceType(); 3376 bool isRValueRef = !isLValueRef; 3377 bool DerivedToBase = false; 3378 bool ObjCConversion = false; 3379 bool ObjCLifetimeConversion = false; 3380 Expr::Classification InitCategory = Initializer->Classify(S.Context); 3381 Sema::ReferenceCompareResult RefRelationship 3382 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase, 3383 ObjCConversion, ObjCLifetimeConversion); 3384 3385 // C++0x [dcl.init.ref]p5: 3386 // A reference to type "cv1 T1" is initialized by an expression of type 3387 // "cv2 T2" as follows: 3388 // 3389 // - If the reference is an lvalue reference and the initializer 3390 // expression 3391 // Note the analogous bullet points for rvlaue refs to functions. Because 3392 // there are no function rvalues in C++, rvalue refs to functions are treated 3393 // like lvalue refs. 3394 OverloadingResult ConvOvlResult = OR_Success; 3395 bool T1Function = T1->isFunctionType(); 3396 if (isLValueRef || T1Function) { 3397 if (InitCategory.isLValue() && 3398 (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification || 3399 (Kind.isCStyleOrFunctionalCast() && 3400 RefRelationship == Sema::Ref_Related))) { 3401 // - is an lvalue (but is not a bit-field), and "cv1 T1" is 3402 // reference-compatible with "cv2 T2," or 3403 // 3404 // Per C++ [over.best.ics]p2, we don't diagnose whether the lvalue is a 3405 // bit-field when we're determining whether the reference initialization 3406 // can occur. However, we do pay attention to whether it is a bit-field 3407 // to decide whether we're actually binding to a temporary created from 3408 // the bit-field. 3409 if (DerivedToBase) 3410 Sequence.AddDerivedToBaseCastStep( 3411 S.Context.getQualifiedType(T1, T2Quals), 3412 VK_LValue); 3413 else if (ObjCConversion) 3414 Sequence.AddObjCObjectConversionStep( 3415 S.Context.getQualifiedType(T1, T2Quals)); 3416 3417 if (T1Quals != T2Quals) 3418 Sequence.AddQualificationConversionStep(cv1T1, VK_LValue); 3419 bool BindingTemporary = T1Quals.hasConst() && !T1Quals.hasVolatile() && 3420 (Initializer->getBitField() || Initializer->refersToVectorElement()); 3421 Sequence.AddReferenceBindingStep(cv1T1, BindingTemporary); 3422 return; 3423 } 3424 3425 // - has a class type (i.e., T2 is a class type), where T1 is not 3426 // reference-related to T2, and can be implicitly converted to an 3427 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible 3428 // with "cv3 T3" (this conversion is selected by enumerating the 3429 // applicable conversion functions (13.3.1.6) and choosing the best 3430 // one through overload resolution (13.3)), 3431 // If we have an rvalue ref to function type here, the rhs must be 3432 // an rvalue. 3433 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() && 3434 (isLValueRef || InitCategory.isRValue())) { 3435 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, Kind, 3436 Initializer, 3437 /*AllowRValues=*/isRValueRef, 3438 Sequence); 3439 if (ConvOvlResult == OR_Success) 3440 return; 3441 if (ConvOvlResult != OR_No_Viable_Function) { 3442 Sequence.SetOverloadFailure( 3443 InitializationSequence::FK_ReferenceInitOverloadFailed, 3444 ConvOvlResult); 3445 } 3446 } 3447 } 3448 3449 // - Otherwise, the reference shall be an lvalue reference to a 3450 // non-volatile const type (i.e., cv1 shall be const), or the reference 3451 // shall be an rvalue reference. 3452 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile())) { 3453 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) 3454 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 3455 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 3456 Sequence.SetOverloadFailure( 3457 InitializationSequence::FK_ReferenceInitOverloadFailed, 3458 ConvOvlResult); 3459 else 3460 Sequence.SetFailed(InitCategory.isLValue() 3461 ? (RefRelationship == Sema::Ref_Related 3462 ? InitializationSequence::FK_ReferenceInitDropsQualifiers 3463 : InitializationSequence::FK_NonConstLValueReferenceBindingToUnrelated) 3464 : InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); 3465 3466 return; 3467 } 3468 3469 // - If the initializer expression 3470 // - is an xvalue, class prvalue, array prvalue, or function lvalue and 3471 // "cv1 T1" is reference-compatible with "cv2 T2" 3472 // Note: functions are handled below. 3473 if (!T1Function && 3474 (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification || 3475 (Kind.isCStyleOrFunctionalCast() && 3476 RefRelationship == Sema::Ref_Related)) && 3477 (InitCategory.isXValue() || 3478 (InitCategory.isPRValue() && T2->isRecordType()) || 3479 (InitCategory.isPRValue() && T2->isArrayType()))) { 3480 ExprValueKind ValueKind = InitCategory.isXValue()? VK_XValue : VK_RValue; 3481 if (InitCategory.isPRValue() && T2->isRecordType()) { 3482 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the 3483 // compiler the freedom to perform a copy here or bind to the 3484 // object, while C++0x requires that we bind directly to the 3485 // object. Hence, we always bind to the object without making an 3486 // extra copy. However, in C++03 requires that we check for the 3487 // presence of a suitable copy constructor: 3488 // 3489 // The constructor that would be used to make the copy shall 3490 // be callable whether or not the copy is actually done. 3491 if (!S.getLangOpts().CPlusPlus0x && !S.getLangOpts().MicrosoftExt) 3492 Sequence.AddExtraneousCopyToTemporary(cv2T2); 3493 else if (S.getLangOpts().CPlusPlus0x) 3494 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer); 3495 } 3496 3497 if (DerivedToBase) 3498 Sequence.AddDerivedToBaseCastStep(S.Context.getQualifiedType(T1, T2Quals), 3499 ValueKind); 3500 else if (ObjCConversion) 3501 Sequence.AddObjCObjectConversionStep( 3502 S.Context.getQualifiedType(T1, T2Quals)); 3503 3504 if (T1Quals != T2Quals) 3505 Sequence.AddQualificationConversionStep(cv1T1, ValueKind); 3506 Sequence.AddReferenceBindingStep(cv1T1, 3507 /*bindingTemporary=*/InitCategory.isPRValue()); 3508 return; 3509 } 3510 3511 // - has a class type (i.e., T2 is a class type), where T1 is not 3512 // reference-related to T2, and can be implicitly converted to an 3513 // xvalue, class prvalue, or function lvalue of type "cv3 T3", 3514 // where "cv1 T1" is reference-compatible with "cv3 T3", 3515 if (T2->isRecordType()) { 3516 if (RefRelationship == Sema::Ref_Incompatible) { 3517 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, 3518 Kind, Initializer, 3519 /*AllowRValues=*/true, 3520 Sequence); 3521 if (ConvOvlResult) 3522 Sequence.SetOverloadFailure( 3523 InitializationSequence::FK_ReferenceInitOverloadFailed, 3524 ConvOvlResult); 3525 3526 return; 3527 } 3528 3529 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 3530 return; 3531 } 3532 3533 // - Otherwise, a temporary of type "cv1 T1" is created and initialized 3534 // from the initializer expression using the rules for a non-reference 3535 // copy initialization (8.5). The reference is then bound to the 3536 // temporary. [...] 3537 3538 // Determine whether we are allowed to call explicit constructors or 3539 // explicit conversion operators. 3540 bool AllowExplicit = Kind.AllowExplicit(); 3541 3542 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); 3543 3544 ImplicitConversionSequence ICS 3545 = S.TryImplicitConversion(Initializer, TempEntity.getType(), 3546 /*SuppressUserConversions*/ false, 3547 AllowExplicit, 3548 /*FIXME:InOverloadResolution=*/false, 3549 /*CStyle=*/Kind.isCStyleOrFunctionalCast(), 3550 /*AllowObjCWritebackConversion=*/false); 3551 3552 if (ICS.isBad()) { 3553 // FIXME: Use the conversion function set stored in ICS to turn 3554 // this into an overloading ambiguity diagnostic. However, we need 3555 // to keep that set as an OverloadCandidateSet rather than as some 3556 // other kind of set. 3557 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 3558 Sequence.SetOverloadFailure( 3559 InitializationSequence::FK_ReferenceInitOverloadFailed, 3560 ConvOvlResult); 3561 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) 3562 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 3563 else 3564 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed); 3565 return; 3566 } else { 3567 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType()); 3568 } 3569 3570 // [...] If T1 is reference-related to T2, cv1 must be the 3571 // same cv-qualification as, or greater cv-qualification 3572 // than, cv2; otherwise, the program is ill-formed. 3573 unsigned T1CVRQuals = T1Quals.getCVRQualifiers(); 3574 unsigned T2CVRQuals = T2Quals.getCVRQualifiers(); 3575 if (RefRelationship == Sema::Ref_Related && 3576 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) { 3577 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 3578 return; 3579 } 3580 3581 // [...] If T1 is reference-related to T2 and the reference is an rvalue 3582 // reference, the initializer expression shall not be an lvalue. 3583 if (RefRelationship >= Sema::Ref_Related && !isLValueRef && 3584 InitCategory.isLValue()) { 3585 Sequence.SetFailed( 3586 InitializationSequence::FK_RValueReferenceBindingToLValue); 3587 return; 3588 } 3589 3590 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 3591 return; 3592 } 3593 3594 /// \brief Attempt character array initialization from a string literal 3595 /// (C++ [dcl.init.string], C99 6.7.8). 3596 static void TryStringLiteralInitialization(Sema &S, 3597 const InitializedEntity &Entity, 3598 const InitializationKind &Kind, 3599 Expr *Initializer, 3600 InitializationSequence &Sequence) { 3601 Sequence.AddStringInitStep(Entity.getType()); 3602 } 3603 3604 /// \brief Attempt value initialization (C++ [dcl.init]p7). 3605 static void TryValueInitialization(Sema &S, 3606 const InitializedEntity &Entity, 3607 const InitializationKind &Kind, 3608 InitializationSequence &Sequence) { 3609 // C++98 [dcl.init]p5, C++11 [dcl.init]p7: 3610 // 3611 // To value-initialize an object of type T means: 3612 QualType T = Entity.getType(); 3613 3614 // -- if T is an array type, then each element is value-initialized; 3615 T = S.Context.getBaseElementType(T); 3616 3617 if (const RecordType *RT = T->getAs<RecordType>()) { 3618 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 3619 // C++98: 3620 // -- if T is a class type (clause 9) with a user-declared 3621 // constructor (12.1), then the default constructor for T is 3622 // called (and the initialization is ill-formed if T has no 3623 // accessible default constructor); 3624 if (!S.getLangOpts().CPlusPlus0x) { 3625 if (ClassDecl->hasUserDeclaredConstructor()) 3626 // FIXME: we really want to refer to a single subobject of the array, 3627 // but Entity doesn't have a way to capture that (yet). 3628 return TryConstructorInitialization(S, Entity, Kind, 0, 0, 3629 T, Sequence); 3630 } else { 3631 // C++11: 3632 // -- if T is a class type (clause 9) with either no default constructor 3633 // (12.1 [class.ctor]) or a default constructor that is user-provided 3634 // or deleted, then the object is default-initialized; 3635 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl); 3636 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted()) 3637 return TryConstructorInitialization(S, Entity, Kind, 0, 0, 3638 T, Sequence); 3639 } 3640 3641 // -- if T is a (possibly cv-qualified) non-union class type without a 3642 // user-provided or deleted default constructor, then the object is 3643 // zero-initialized and, if T has a non-trivial default constructor, 3644 // default-initialized; 3645 if ((ClassDecl->getTagKind() == TTK_Class || 3646 ClassDecl->getTagKind() == TTK_Struct)) { 3647 Sequence.AddZeroInitializationStep(Entity.getType()); 3648 return TryConstructorInitialization(S, Entity, Kind, 0, 0, T, Sequence); 3649 } 3650 } 3651 } 3652 3653 Sequence.AddZeroInitializationStep(Entity.getType()); 3654 } 3655 3656 /// \brief Attempt default initialization (C++ [dcl.init]p6). 3657 static void TryDefaultInitialization(Sema &S, 3658 const InitializedEntity &Entity, 3659 const InitializationKind &Kind, 3660 InitializationSequence &Sequence) { 3661 assert(Kind.getKind() == InitializationKind::IK_Default); 3662 3663 // C++ [dcl.init]p6: 3664 // To default-initialize an object of type T means: 3665 // - if T is an array type, each element is default-initialized; 3666 QualType DestType = S.Context.getBaseElementType(Entity.getType()); 3667 3668 // - if T is a (possibly cv-qualified) class type (Clause 9), the default 3669 // constructor for T is called (and the initialization is ill-formed if 3670 // T has no accessible default constructor); 3671 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) { 3672 TryConstructorInitialization(S, Entity, Kind, 0, 0, DestType, Sequence); 3673 return; 3674 } 3675 3676 // - otherwise, no initialization is performed. 3677 3678 // If a program calls for the default initialization of an object of 3679 // a const-qualified type T, T shall be a class type with a user-provided 3680 // default constructor. 3681 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) { 3682 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 3683 return; 3684 } 3685 3686 // If the destination type has a lifetime property, zero-initialize it. 3687 if (DestType.getQualifiers().hasObjCLifetime()) { 3688 Sequence.AddZeroInitializationStep(Entity.getType()); 3689 return; 3690 } 3691 } 3692 3693 /// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]), 3694 /// which enumerates all conversion functions and performs overload resolution 3695 /// to select the best. 3696 static void TryUserDefinedConversion(Sema &S, 3697 const InitializedEntity &Entity, 3698 const InitializationKind &Kind, 3699 Expr *Initializer, 3700 InitializationSequence &Sequence) { 3701 QualType DestType = Entity.getType(); 3702 assert(!DestType->isReferenceType() && "References are handled elsewhere"); 3703 QualType SourceType = Initializer->getType(); 3704 assert((DestType->isRecordType() || SourceType->isRecordType()) && 3705 "Must have a class type to perform a user-defined conversion"); 3706 3707 // Build the candidate set directly in the initialization sequence 3708 // structure, so that it will persist if we fail. 3709 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 3710 CandidateSet.clear(); 3711 3712 // Determine whether we are allowed to call explicit constructors or 3713 // explicit conversion operators. 3714 bool AllowExplicit = Kind.AllowExplicit(); 3715 3716 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) { 3717 // The type we're converting to is a class type. Enumerate its constructors 3718 // to see if there is a suitable conversion. 3719 CXXRecordDecl *DestRecordDecl 3720 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 3721 3722 // Try to complete the type we're converting to. 3723 if (!S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { 3724 DeclContext::lookup_iterator Con, ConEnd; 3725 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(DestRecordDecl); 3726 Con != ConEnd; ++Con) { 3727 NamedDecl *D = *Con; 3728 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 3729 3730 // Find the constructor (which may be a template). 3731 CXXConstructorDecl *Constructor = 0; 3732 FunctionTemplateDecl *ConstructorTmpl 3733 = dyn_cast<FunctionTemplateDecl>(D); 3734 if (ConstructorTmpl) 3735 Constructor = cast<CXXConstructorDecl>( 3736 ConstructorTmpl->getTemplatedDecl()); 3737 else 3738 Constructor = cast<CXXConstructorDecl>(D); 3739 3740 if (!Constructor->isInvalidDecl() && 3741 Constructor->isConvertingConstructor(AllowExplicit)) { 3742 if (ConstructorTmpl) 3743 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 3744 /*ExplicitArgs*/ 0, 3745 Initializer, CandidateSet, 3746 /*SuppressUserConversions=*/true); 3747 else 3748 S.AddOverloadCandidate(Constructor, FoundDecl, 3749 Initializer, CandidateSet, 3750 /*SuppressUserConversions=*/true); 3751 } 3752 } 3753 } 3754 } 3755 3756 SourceLocation DeclLoc = Initializer->getLocStart(); 3757 3758 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) { 3759 // The type we're converting from is a class type, enumerate its conversion 3760 // functions. 3761 3762 // We can only enumerate the conversion functions for a complete type; if 3763 // the type isn't complete, simply skip this step. 3764 if (!S.RequireCompleteType(DeclLoc, SourceType, 0)) { 3765 CXXRecordDecl *SourceRecordDecl 3766 = cast<CXXRecordDecl>(SourceRecordType->getDecl()); 3767 3768 const UnresolvedSetImpl *Conversions 3769 = SourceRecordDecl->getVisibleConversionFunctions(); 3770 for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), 3771 E = Conversions->end(); 3772 I != E; ++I) { 3773 NamedDecl *D = *I; 3774 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3775 if (isa<UsingShadowDecl>(D)) 3776 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3777 3778 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 3779 CXXConversionDecl *Conv; 3780 if (ConvTemplate) 3781 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3782 else 3783 Conv = cast<CXXConversionDecl>(D); 3784 3785 if (AllowExplicit || !Conv->isExplicit()) { 3786 if (ConvTemplate) 3787 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 3788 ActingDC, Initializer, DestType, 3789 CandidateSet); 3790 else 3791 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 3792 Initializer, DestType, CandidateSet); 3793 } 3794 } 3795 } 3796 } 3797 3798 // Perform overload resolution. If it fails, return the failed result. 3799 OverloadCandidateSet::iterator Best; 3800 if (OverloadingResult Result 3801 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3802 Sequence.SetOverloadFailure( 3803 InitializationSequence::FK_UserConversionOverloadFailed, 3804 Result); 3805 return; 3806 } 3807 3808 FunctionDecl *Function = Best->Function; 3809 S.MarkFunctionReferenced(DeclLoc, Function); 3810 bool HadMultipleCandidates = (CandidateSet.size() > 1); 3811 3812 if (isa<CXXConstructorDecl>(Function)) { 3813 // Add the user-defined conversion step. Any cv-qualification conversion is 3814 // subsumed by the initialization. Per DR5, the created temporary is of the 3815 // cv-unqualified type of the destination. 3816 Sequence.AddUserConversionStep(Function, Best->FoundDecl, 3817 DestType.getUnqualifiedType(), 3818 HadMultipleCandidates); 3819 return; 3820 } 3821 3822 // Add the user-defined conversion step that calls the conversion function. 3823 QualType ConvType = Function->getCallResultType(); 3824 if (ConvType->getAs<RecordType>()) { 3825 // If we're converting to a class type, there may be an copy of 3826 // the resulting temporary object (possible to create an object of 3827 // a base class type). That copy is not a separate conversion, so 3828 // we just make a note of the actual destination type (possibly a 3829 // base class of the type returned by the conversion function) and 3830 // let the user-defined conversion step handle the conversion. 3831 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType, 3832 HadMultipleCandidates); 3833 return; 3834 } 3835 3836 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType, 3837 HadMultipleCandidates); 3838 3839 // If the conversion following the call to the conversion function 3840 // is interesting, add it as a separate step. 3841 if (Best->FinalConversion.First || Best->FinalConversion.Second || 3842 Best->FinalConversion.Third) { 3843 ImplicitConversionSequence ICS; 3844 ICS.setStandard(); 3845 ICS.Standard = Best->FinalConversion; 3846 Sequence.AddConversionSequenceStep(ICS, DestType); 3847 } 3848 } 3849 3850 /// The non-zero enum values here are indexes into diagnostic alternatives. 3851 enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar }; 3852 3853 /// Determines whether this expression is an acceptable ICR source. 3854 static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e, 3855 bool isAddressOf) { 3856 // Skip parens. 3857 e = e->IgnoreParens(); 3858 3859 // Skip address-of nodes. 3860 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) { 3861 if (op->getOpcode() == UO_AddrOf) 3862 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true); 3863 3864 // Skip certain casts. 3865 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) { 3866 switch (ce->getCastKind()) { 3867 case CK_Dependent: 3868 case CK_BitCast: 3869 case CK_LValueBitCast: 3870 case CK_NoOp: 3871 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf); 3872 3873 case CK_ArrayToPointerDecay: 3874 return IIK_nonscalar; 3875 3876 case CK_NullToPointer: 3877 return IIK_okay; 3878 3879 default: 3880 break; 3881 } 3882 3883 // If we have a declaration reference, it had better be a local variable. 3884 } else if (isa<DeclRefExpr>(e)) { 3885 if (!isAddressOf) return IIK_nonlocal; 3886 3887 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl()); 3888 if (!var) return IIK_nonlocal; 3889 3890 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal); 3891 3892 // If we have a conditional operator, check both sides. 3893 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) { 3894 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf)) 3895 return iik; 3896 3897 return isInvalidICRSource(C, cond->getRHS(), isAddressOf); 3898 3899 // These are never scalar. 3900 } else if (isa<ArraySubscriptExpr>(e)) { 3901 return IIK_nonscalar; 3902 3903 // Otherwise, it needs to be a null pointer constant. 3904 } else { 3905 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull) 3906 ? IIK_okay : IIK_nonlocal); 3907 } 3908 3909 return IIK_nonlocal; 3910 } 3911 3912 /// Check whether the given expression is a valid operand for an 3913 /// indirect copy/restore. 3914 static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) { 3915 assert(src->isRValue()); 3916 3917 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false); 3918 if (iik == IIK_okay) return; 3919 3920 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback) 3921 << ((unsigned) iik - 1) // shift index into diagnostic explanations 3922 << src->getSourceRange(); 3923 } 3924 3925 /// \brief Determine whether we have compatible array types for the 3926 /// purposes of GNU by-copy array initialization. 3927 static bool hasCompatibleArrayTypes(ASTContext &Context, 3928 const ArrayType *Dest, 3929 const ArrayType *Source) { 3930 // If the source and destination array types are equivalent, we're 3931 // done. 3932 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0))) 3933 return true; 3934 3935 // Make sure that the element types are the same. 3936 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType())) 3937 return false; 3938 3939 // The only mismatch we allow is when the destination is an 3940 // incomplete array type and the source is a constant array type. 3941 return Source->isConstantArrayType() && Dest->isIncompleteArrayType(); 3942 } 3943 3944 static bool tryObjCWritebackConversion(Sema &S, 3945 InitializationSequence &Sequence, 3946 const InitializedEntity &Entity, 3947 Expr *Initializer) { 3948 bool ArrayDecay = false; 3949 QualType ArgType = Initializer->getType(); 3950 QualType ArgPointee; 3951 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) { 3952 ArrayDecay = true; 3953 ArgPointee = ArgArrayType->getElementType(); 3954 ArgType = S.Context.getPointerType(ArgPointee); 3955 } 3956 3957 // Handle write-back conversion. 3958 QualType ConvertedArgType; 3959 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(), 3960 ConvertedArgType)) 3961 return false; 3962 3963 // We should copy unless we're passing to an argument explicitly 3964 // marked 'out'. 3965 bool ShouldCopy = true; 3966 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl())) 3967 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out); 3968 3969 // Do we need an lvalue conversion? 3970 if (ArrayDecay || Initializer->isGLValue()) { 3971 ImplicitConversionSequence ICS; 3972 ICS.setStandard(); 3973 ICS.Standard.setAsIdentityConversion(); 3974 3975 QualType ResultType; 3976 if (ArrayDecay) { 3977 ICS.Standard.First = ICK_Array_To_Pointer; 3978 ResultType = S.Context.getPointerType(ArgPointee); 3979 } else { 3980 ICS.Standard.First = ICK_Lvalue_To_Rvalue; 3981 ResultType = Initializer->getType().getNonLValueExprType(S.Context); 3982 } 3983 3984 Sequence.AddConversionSequenceStep(ICS, ResultType); 3985 } 3986 3987 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy); 3988 return true; 3989 } 3990 3991 InitializationSequence::InitializationSequence(Sema &S, 3992 const InitializedEntity &Entity, 3993 const InitializationKind &Kind, 3994 Expr **Args, 3995 unsigned NumArgs) 3996 : FailedCandidateSet(Kind.getLocation()) { 3997 ASTContext &Context = S.Context; 3998 3999 // C++0x [dcl.init]p16: 4000 // The semantics of initializers are as follows. The destination type is 4001 // the type of the object or reference being initialized and the source 4002 // type is the type of the initializer expression. The source type is not 4003 // defined when the initializer is a braced-init-list or when it is a 4004 // parenthesized list of expressions. 4005 QualType DestType = Entity.getType(); 4006 4007 if (DestType->isDependentType() || 4008 Expr::hasAnyTypeDependentArguments(llvm::makeArrayRef(Args, NumArgs))) { 4009 SequenceKind = DependentSequence; 4010 return; 4011 } 4012 4013 // Almost everything is a normal sequence. 4014 setSequenceKind(NormalSequence); 4015 4016 for (unsigned I = 0; I != NumArgs; ++I) 4017 if (Args[I]->getType()->isNonOverloadPlaceholderType()) { 4018 // FIXME: should we be doing this here? 4019 ExprResult result = S.CheckPlaceholderExpr(Args[I]); 4020 if (result.isInvalid()) { 4021 SetFailed(FK_PlaceholderType); 4022 return; 4023 } 4024 Args[I] = result.take(); 4025 } 4026 4027 4028 QualType SourceType; 4029 Expr *Initializer = 0; 4030 if (NumArgs == 1) { 4031 Initializer = Args[0]; 4032 if (!isa<InitListExpr>(Initializer)) 4033 SourceType = Initializer->getType(); 4034 } 4035 4036 // - If the initializer is a (non-parenthesized) braced-init-list, the 4037 // object is list-initialized (8.5.4). 4038 if (Kind.getKind() != InitializationKind::IK_Direct) { 4039 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) { 4040 TryListInitialization(S, Entity, Kind, InitList, *this); 4041 return; 4042 } 4043 } 4044 4045 // - If the destination type is a reference type, see 8.5.3. 4046 if (DestType->isReferenceType()) { 4047 // C++0x [dcl.init.ref]p1: 4048 // A variable declared to be a T& or T&&, that is, "reference to type T" 4049 // (8.3.2), shall be initialized by an object, or function, of type T or 4050 // by an object that can be converted into a T. 4051 // (Therefore, multiple arguments are not permitted.) 4052 if (NumArgs != 1) 4053 SetFailed(FK_TooManyInitsForReference); 4054 else 4055 TryReferenceInitialization(S, Entity, Kind, Args[0], *this); 4056 return; 4057 } 4058 4059 // - If the initializer is (), the object is value-initialized. 4060 if (Kind.getKind() == InitializationKind::IK_Value || 4061 (Kind.getKind() == InitializationKind::IK_Direct && NumArgs == 0)) { 4062 TryValueInitialization(S, Entity, Kind, *this); 4063 return; 4064 } 4065 4066 // Handle default initialization. 4067 if (Kind.getKind() == InitializationKind::IK_Default) { 4068 TryDefaultInitialization(S, Entity, Kind, *this); 4069 return; 4070 } 4071 4072 // - If the destination type is an array of characters, an array of 4073 // char16_t, an array of char32_t, or an array of wchar_t, and the 4074 // initializer is a string literal, see 8.5.2. 4075 // - Otherwise, if the destination type is an array, the program is 4076 // ill-formed. 4077 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) { 4078 if (Initializer && isa<VariableArrayType>(DestAT)) { 4079 SetFailed(FK_VariableLengthArrayHasInitializer); 4080 return; 4081 } 4082 4083 if (Initializer && IsStringInit(Initializer, DestAT, Context)) { 4084 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this); 4085 return; 4086 } 4087 4088 // Note: as an GNU C extension, we allow initialization of an 4089 // array from a compound literal that creates an array of the same 4090 // type, so long as the initializer has no side effects. 4091 if (!S.getLangOpts().CPlusPlus && Initializer && 4092 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) && 4093 Initializer->getType()->isArrayType()) { 4094 const ArrayType *SourceAT 4095 = Context.getAsArrayType(Initializer->getType()); 4096 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT)) 4097 SetFailed(FK_ArrayTypeMismatch); 4098 else if (Initializer->HasSideEffects(S.Context)) 4099 SetFailed(FK_NonConstantArrayInit); 4100 else { 4101 AddArrayInitStep(DestType); 4102 } 4103 } 4104 // Note: as a GNU C++ extension, we allow initialization of a 4105 // class member from a parenthesized initializer list. 4106 else if (S.getLangOpts().CPlusPlus && 4107 Entity.getKind() == InitializedEntity::EK_Member && 4108 Initializer && isa<InitListExpr>(Initializer)) { 4109 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer), 4110 *this); 4111 AddParenthesizedArrayInitStep(DestType); 4112 } else if (DestAT->getElementType()->isAnyCharacterType()) 4113 SetFailed(FK_ArrayNeedsInitListOrStringLiteral); 4114 else 4115 SetFailed(FK_ArrayNeedsInitList); 4116 4117 return; 4118 } 4119 4120 // Determine whether we should consider writeback conversions for 4121 // Objective-C ARC. 4122 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount && 4123 Entity.getKind() == InitializedEntity::EK_Parameter; 4124 4125 // We're at the end of the line for C: it's either a write-back conversion 4126 // or it's a C assignment. There's no need to check anything else. 4127 if (!S.getLangOpts().CPlusPlus) { 4128 // If allowed, check whether this is an Objective-C writeback conversion. 4129 if (allowObjCWritebackConversion && 4130 tryObjCWritebackConversion(S, *this, Entity, Initializer)) { 4131 return; 4132 } 4133 4134 // Handle initialization in C 4135 AddCAssignmentStep(DestType); 4136 MaybeProduceObjCObject(S, *this, Entity); 4137 return; 4138 } 4139 4140 assert(S.getLangOpts().CPlusPlus); 4141 4142 // - If the destination type is a (possibly cv-qualified) class type: 4143 if (DestType->isRecordType()) { 4144 // - If the initialization is direct-initialization, or if it is 4145 // copy-initialization where the cv-unqualified version of the 4146 // source type is the same class as, or a derived class of, the 4147 // class of the destination, constructors are considered. [...] 4148 if (Kind.getKind() == InitializationKind::IK_Direct || 4149 (Kind.getKind() == InitializationKind::IK_Copy && 4150 (Context.hasSameUnqualifiedType(SourceType, DestType) || 4151 S.IsDerivedFrom(SourceType, DestType)))) 4152 TryConstructorInitialization(S, Entity, Kind, Args, NumArgs, 4153 Entity.getType(), *this); 4154 // - Otherwise (i.e., for the remaining copy-initialization cases), 4155 // user-defined conversion sequences that can convert from the source 4156 // type to the destination type or (when a conversion function is 4157 // used) to a derived class thereof are enumerated as described in 4158 // 13.3.1.4, and the best one is chosen through overload resolution 4159 // (13.3). 4160 else 4161 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 4162 return; 4163 } 4164 4165 if (NumArgs > 1) { 4166 SetFailed(FK_TooManyInitsForScalar); 4167 return; 4168 } 4169 assert(NumArgs == 1 && "Zero-argument case handled above"); 4170 4171 // - Otherwise, if the source type is a (possibly cv-qualified) class 4172 // type, conversion functions are considered. 4173 if (!SourceType.isNull() && SourceType->isRecordType()) { 4174 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 4175 MaybeProduceObjCObject(S, *this, Entity); 4176 return; 4177 } 4178 4179 // - Otherwise, the initial value of the object being initialized is the 4180 // (possibly converted) value of the initializer expression. Standard 4181 // conversions (Clause 4) will be used, if necessary, to convert the 4182 // initializer expression to the cv-unqualified version of the 4183 // destination type; no user-defined conversions are considered. 4184 4185 ImplicitConversionSequence ICS 4186 = S.TryImplicitConversion(Initializer, Entity.getType(), 4187 /*SuppressUserConversions*/true, 4188 /*AllowExplicitConversions*/ false, 4189 /*InOverloadResolution*/ false, 4190 /*CStyle=*/Kind.isCStyleOrFunctionalCast(), 4191 allowObjCWritebackConversion); 4192 4193 if (ICS.isStandard() && 4194 ICS.Standard.Second == ICK_Writeback_Conversion) { 4195 // Objective-C ARC writeback conversion. 4196 4197 // We should copy unless we're passing to an argument explicitly 4198 // marked 'out'. 4199 bool ShouldCopy = true; 4200 if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl())) 4201 ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out); 4202 4203 // If there was an lvalue adjustment, add it as a separate conversion. 4204 if (ICS.Standard.First == ICK_Array_To_Pointer || 4205 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4206 ImplicitConversionSequence LvalueICS; 4207 LvalueICS.setStandard(); 4208 LvalueICS.Standard.setAsIdentityConversion(); 4209 LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0)); 4210 LvalueICS.Standard.First = ICS.Standard.First; 4211 AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0)); 4212 } 4213 4214 AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy); 4215 } else if (ICS.isBad()) { 4216 DeclAccessPair dap; 4217 if (Initializer->getType() == Context.OverloadTy && 4218 !S.ResolveAddressOfOverloadedFunction(Initializer 4219 , DestType, false, dap)) 4220 SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 4221 else 4222 SetFailed(InitializationSequence::FK_ConversionFailed); 4223 } else { 4224 AddConversionSequenceStep(ICS, Entity.getType()); 4225 4226 MaybeProduceObjCObject(S, *this, Entity); 4227 } 4228 } 4229 4230 InitializationSequence::~InitializationSequence() { 4231 for (SmallVectorImpl<Step>::iterator Step = Steps.begin(), 4232 StepEnd = Steps.end(); 4233 Step != StepEnd; ++Step) 4234 Step->Destroy(); 4235 } 4236 4237 //===----------------------------------------------------------------------===// 4238 // Perform initialization 4239 //===----------------------------------------------------------------------===// 4240 static Sema::AssignmentAction 4241 getAssignmentAction(const InitializedEntity &Entity) { 4242 switch(Entity.getKind()) { 4243 case InitializedEntity::EK_Variable: 4244 case InitializedEntity::EK_New: 4245 case InitializedEntity::EK_Exception: 4246 case InitializedEntity::EK_Base: 4247 case InitializedEntity::EK_Delegating: 4248 return Sema::AA_Initializing; 4249 4250 case InitializedEntity::EK_Parameter: 4251 if (Entity.getDecl() && 4252 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext())) 4253 return Sema::AA_Sending; 4254 4255 return Sema::AA_Passing; 4256 4257 case InitializedEntity::EK_Result: 4258 return Sema::AA_Returning; 4259 4260 case InitializedEntity::EK_Temporary: 4261 // FIXME: Can we tell apart casting vs. converting? 4262 return Sema::AA_Casting; 4263 4264 case InitializedEntity::EK_Member: 4265 case InitializedEntity::EK_ArrayElement: 4266 case InitializedEntity::EK_VectorElement: 4267 case InitializedEntity::EK_ComplexElement: 4268 case InitializedEntity::EK_BlockElement: 4269 case InitializedEntity::EK_LambdaCapture: 4270 return Sema::AA_Initializing; 4271 } 4272 4273 llvm_unreachable("Invalid EntityKind!"); 4274 } 4275 4276 /// \brief Whether we should binding a created object as a temporary when 4277 /// initializing the given entity. 4278 static bool shouldBindAsTemporary(const InitializedEntity &Entity) { 4279 switch (Entity.getKind()) { 4280 case InitializedEntity::EK_ArrayElement: 4281 case InitializedEntity::EK_Member: 4282 case InitializedEntity::EK_Result: 4283 case InitializedEntity::EK_New: 4284 case InitializedEntity::EK_Variable: 4285 case InitializedEntity::EK_Base: 4286 case InitializedEntity::EK_Delegating: 4287 case InitializedEntity::EK_VectorElement: 4288 case InitializedEntity::EK_ComplexElement: 4289 case InitializedEntity::EK_Exception: 4290 case InitializedEntity::EK_BlockElement: 4291 case InitializedEntity::EK_LambdaCapture: 4292 return false; 4293 4294 case InitializedEntity::EK_Parameter: 4295 case InitializedEntity::EK_Temporary: 4296 return true; 4297 } 4298 4299 llvm_unreachable("missed an InitializedEntity kind?"); 4300 } 4301 4302 /// \brief Whether the given entity, when initialized with an object 4303 /// created for that initialization, requires destruction. 4304 static bool shouldDestroyTemporary(const InitializedEntity &Entity) { 4305 switch (Entity.getKind()) { 4306 case InitializedEntity::EK_Member: 4307 case InitializedEntity::EK_Result: 4308 case InitializedEntity::EK_New: 4309 case InitializedEntity::EK_Base: 4310 case InitializedEntity::EK_Delegating: 4311 case InitializedEntity::EK_VectorElement: 4312 case InitializedEntity::EK_ComplexElement: 4313 case InitializedEntity::EK_BlockElement: 4314 case InitializedEntity::EK_LambdaCapture: 4315 return false; 4316 4317 case InitializedEntity::EK_Variable: 4318 case InitializedEntity::EK_Parameter: 4319 case InitializedEntity::EK_Temporary: 4320 case InitializedEntity::EK_ArrayElement: 4321 case InitializedEntity::EK_Exception: 4322 return true; 4323 } 4324 4325 llvm_unreachable("missed an InitializedEntity kind?"); 4326 } 4327 4328 /// \brief Look for copy and move constructors and constructor templates, for 4329 /// copying an object via direct-initialization (per C++11 [dcl.init]p16). 4330 static void LookupCopyAndMoveConstructors(Sema &S, 4331 OverloadCandidateSet &CandidateSet, 4332 CXXRecordDecl *Class, 4333 Expr *CurInitExpr) { 4334 DeclContext::lookup_iterator Con, ConEnd; 4335 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(Class); 4336 Con != ConEnd; ++Con) { 4337 CXXConstructorDecl *Constructor = 0; 4338 4339 if ((Constructor = dyn_cast<CXXConstructorDecl>(*Con))) { 4340 // Handle copy/moveconstructors, only. 4341 if (!Constructor || Constructor->isInvalidDecl() || 4342 !Constructor->isCopyOrMoveConstructor() || 4343 !Constructor->isConvertingConstructor(/*AllowExplicit=*/true)) 4344 continue; 4345 4346 DeclAccessPair FoundDecl 4347 = DeclAccessPair::make(Constructor, Constructor->getAccess()); 4348 S.AddOverloadCandidate(Constructor, FoundDecl, 4349 CurInitExpr, CandidateSet); 4350 continue; 4351 } 4352 4353 // Handle constructor templates. 4354 FunctionTemplateDecl *ConstructorTmpl = cast<FunctionTemplateDecl>(*Con); 4355 if (ConstructorTmpl->isInvalidDecl()) 4356 continue; 4357 4358 Constructor = cast<CXXConstructorDecl>( 4359 ConstructorTmpl->getTemplatedDecl()); 4360 if (!Constructor->isConvertingConstructor(/*AllowExplicit=*/true)) 4361 continue; 4362 4363 // FIXME: Do we need to limit this to copy-constructor-like 4364 // candidates? 4365 DeclAccessPair FoundDecl 4366 = DeclAccessPair::make(ConstructorTmpl, ConstructorTmpl->getAccess()); 4367 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 0, 4368 CurInitExpr, CandidateSet, true); 4369 } 4370 } 4371 4372 /// \brief Get the location at which initialization diagnostics should appear. 4373 static SourceLocation getInitializationLoc(const InitializedEntity &Entity, 4374 Expr *Initializer) { 4375 switch (Entity.getKind()) { 4376 case InitializedEntity::EK_Result: 4377 return Entity.getReturnLoc(); 4378 4379 case InitializedEntity::EK_Exception: 4380 return Entity.getThrowLoc(); 4381 4382 case InitializedEntity::EK_Variable: 4383 return Entity.getDecl()->getLocation(); 4384 4385 case InitializedEntity::EK_LambdaCapture: 4386 return Entity.getCaptureLoc(); 4387 4388 case InitializedEntity::EK_ArrayElement: 4389 case InitializedEntity::EK_Member: 4390 case InitializedEntity::EK_Parameter: 4391 case InitializedEntity::EK_Temporary: 4392 case InitializedEntity::EK_New: 4393 case InitializedEntity::EK_Base: 4394 case InitializedEntity::EK_Delegating: 4395 case InitializedEntity::EK_VectorElement: 4396 case InitializedEntity::EK_ComplexElement: 4397 case InitializedEntity::EK_BlockElement: 4398 return Initializer->getLocStart(); 4399 } 4400 llvm_unreachable("missed an InitializedEntity kind?"); 4401 } 4402 4403 /// \brief Make a (potentially elidable) temporary copy of the object 4404 /// provided by the given initializer by calling the appropriate copy 4405 /// constructor. 4406 /// 4407 /// \param S The Sema object used for type-checking. 4408 /// 4409 /// \param T The type of the temporary object, which must either be 4410 /// the type of the initializer expression or a superclass thereof. 4411 /// 4412 /// \param Enter The entity being initialized. 4413 /// 4414 /// \param CurInit The initializer expression. 4415 /// 4416 /// \param IsExtraneousCopy Whether this is an "extraneous" copy that 4417 /// is permitted in C++03 (but not C++0x) when binding a reference to 4418 /// an rvalue. 4419 /// 4420 /// \returns An expression that copies the initializer expression into 4421 /// a temporary object, or an error expression if a copy could not be 4422 /// created. 4423 static ExprResult CopyObject(Sema &S, 4424 QualType T, 4425 const InitializedEntity &Entity, 4426 ExprResult CurInit, 4427 bool IsExtraneousCopy) { 4428 // Determine which class type we're copying to. 4429 Expr *CurInitExpr = (Expr *)CurInit.get(); 4430 CXXRecordDecl *Class = 0; 4431 if (const RecordType *Record = T->getAs<RecordType>()) 4432 Class = cast<CXXRecordDecl>(Record->getDecl()); 4433 if (!Class) 4434 return move(CurInit); 4435 4436 // C++0x [class.copy]p32: 4437 // When certain criteria are met, an implementation is allowed to 4438 // omit the copy/move construction of a class object, even if the 4439 // copy/move constructor and/or destructor for the object have 4440 // side effects. [...] 4441 // - when a temporary class object that has not been bound to a 4442 // reference (12.2) would be copied/moved to a class object 4443 // with the same cv-unqualified type, the copy/move operation 4444 // can be omitted by constructing the temporary object 4445 // directly into the target of the omitted copy/move 4446 // 4447 // Note that the other three bullets are handled elsewhere. Copy 4448 // elision for return statements and throw expressions are handled as part 4449 // of constructor initialization, while copy elision for exception handlers 4450 // is handled by the run-time. 4451 bool Elidable = CurInitExpr->isTemporaryObject(S.Context, Class); 4452 SourceLocation Loc = getInitializationLoc(Entity, CurInit.get()); 4453 4454 // Make sure that the type we are copying is complete. 4455 if (S.RequireCompleteType(Loc, T, S.PDiag(diag::err_temp_copy_incomplete))) 4456 return move(CurInit); 4457 4458 // Perform overload resolution using the class's copy/move constructors. 4459 // Only consider constructors and constructor templates. Per 4460 // C++0x [dcl.init]p16, second bullet to class types, this initialization 4461 // is direct-initialization. 4462 OverloadCandidateSet CandidateSet(Loc); 4463 LookupCopyAndMoveConstructors(S, CandidateSet, Class, CurInitExpr); 4464 4465 bool HadMultipleCandidates = (CandidateSet.size() > 1); 4466 4467 OverloadCandidateSet::iterator Best; 4468 switch (CandidateSet.BestViableFunction(S, Loc, Best)) { 4469 case OR_Success: 4470 break; 4471 4472 case OR_No_Viable_Function: 4473 S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext() 4474 ? diag::ext_rvalue_to_reference_temp_copy_no_viable 4475 : diag::err_temp_copy_no_viable) 4476 << (int)Entity.getKind() << CurInitExpr->getType() 4477 << CurInitExpr->getSourceRange(); 4478 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr); 4479 if (!IsExtraneousCopy || S.isSFINAEContext()) 4480 return ExprError(); 4481 return move(CurInit); 4482 4483 case OR_Ambiguous: 4484 S.Diag(Loc, diag::err_temp_copy_ambiguous) 4485 << (int)Entity.getKind() << CurInitExpr->getType() 4486 << CurInitExpr->getSourceRange(); 4487 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr); 4488 return ExprError(); 4489 4490 case OR_Deleted: 4491 S.Diag(Loc, diag::err_temp_copy_deleted) 4492 << (int)Entity.getKind() << CurInitExpr->getType() 4493 << CurInitExpr->getSourceRange(); 4494 S.NoteDeletedFunction(Best->Function); 4495 return ExprError(); 4496 } 4497 4498 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function); 4499 ASTOwningVector<Expr*> ConstructorArgs(S); 4500 CurInit.release(); // Ownership transferred into MultiExprArg, below. 4501 4502 S.CheckConstructorAccess(Loc, Constructor, Entity, 4503 Best->FoundDecl.getAccess(), IsExtraneousCopy); 4504 4505 if (IsExtraneousCopy) { 4506 // If this is a totally extraneous copy for C++03 reference 4507 // binding purposes, just return the original initialization 4508 // expression. We don't generate an (elided) copy operation here 4509 // because doing so would require us to pass down a flag to avoid 4510 // infinite recursion, where each step adds another extraneous, 4511 // elidable copy. 4512 4513 // Instantiate the default arguments of any extra parameters in 4514 // the selected copy constructor, as if we were going to create a 4515 // proper call to the copy constructor. 4516 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) { 4517 ParmVarDecl *Parm = Constructor->getParamDecl(I); 4518 if (S.RequireCompleteType(Loc, Parm->getType(), 4519 S.PDiag(diag::err_call_incomplete_argument))) 4520 break; 4521 4522 // Build the default argument expression; we don't actually care 4523 // if this succeeds or not, because this routine will complain 4524 // if there was a problem. 4525 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm); 4526 } 4527 4528 return S.Owned(CurInitExpr); 4529 } 4530 4531 S.MarkFunctionReferenced(Loc, Constructor); 4532 4533 // Determine the arguments required to actually perform the 4534 // constructor call (we might have derived-to-base conversions, or 4535 // the copy constructor may have default arguments). 4536 if (S.CompleteConstructorCall(Constructor, MultiExprArg(&CurInitExpr, 1), 4537 Loc, ConstructorArgs)) 4538 return ExprError(); 4539 4540 // Actually perform the constructor call. 4541 CurInit = S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable, 4542 move_arg(ConstructorArgs), 4543 HadMultipleCandidates, 4544 /*ZeroInit*/ false, 4545 CXXConstructExpr::CK_Complete, 4546 SourceRange()); 4547 4548 // If we're supposed to bind temporaries, do so. 4549 if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity)) 4550 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 4551 return move(CurInit); 4552 } 4553 4554 /// \brief Check whether elidable copy construction for binding a reference to 4555 /// a temporary would have succeeded if we were building in C++98 mode, for 4556 /// -Wc++98-compat. 4557 static void CheckCXX98CompatAccessibleCopy(Sema &S, 4558 const InitializedEntity &Entity, 4559 Expr *CurInitExpr) { 4560 assert(S.getLangOpts().CPlusPlus0x); 4561 4562 const RecordType *Record = CurInitExpr->getType()->getAs<RecordType>(); 4563 if (!Record) 4564 return; 4565 4566 SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr); 4567 if (S.Diags.getDiagnosticLevel(diag::warn_cxx98_compat_temp_copy, Loc) 4568 == DiagnosticsEngine::Ignored) 4569 return; 4570 4571 // Find constructors which would have been considered. 4572 OverloadCandidateSet CandidateSet(Loc); 4573 LookupCopyAndMoveConstructors( 4574 S, CandidateSet, cast<CXXRecordDecl>(Record->getDecl()), CurInitExpr); 4575 4576 // Perform overload resolution. 4577 OverloadCandidateSet::iterator Best; 4578 OverloadingResult OR = CandidateSet.BestViableFunction(S, Loc, Best); 4579 4580 PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy) 4581 << OR << (int)Entity.getKind() << CurInitExpr->getType() 4582 << CurInitExpr->getSourceRange(); 4583 4584 switch (OR) { 4585 case OR_Success: 4586 S.CheckConstructorAccess(Loc, cast<CXXConstructorDecl>(Best->Function), 4587 Entity, Best->FoundDecl.getAccess(), Diag); 4588 // FIXME: Check default arguments as far as that's possible. 4589 break; 4590 4591 case OR_No_Viable_Function: 4592 S.Diag(Loc, Diag); 4593 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr); 4594 break; 4595 4596 case OR_Ambiguous: 4597 S.Diag(Loc, Diag); 4598 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr); 4599 break; 4600 4601 case OR_Deleted: 4602 S.Diag(Loc, Diag); 4603 S.NoteDeletedFunction(Best->Function); 4604 break; 4605 } 4606 } 4607 4608 void InitializationSequence::PrintInitLocationNote(Sema &S, 4609 const InitializedEntity &Entity) { 4610 if (Entity.getKind() == InitializedEntity::EK_Parameter && Entity.getDecl()) { 4611 if (Entity.getDecl()->getLocation().isInvalid()) 4612 return; 4613 4614 if (Entity.getDecl()->getDeclName()) 4615 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here) 4616 << Entity.getDecl()->getDeclName(); 4617 else 4618 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here); 4619 } 4620 } 4621 4622 static bool isReferenceBinding(const InitializationSequence::Step &s) { 4623 return s.Kind == InitializationSequence::SK_BindReference || 4624 s.Kind == InitializationSequence::SK_BindReferenceToTemporary; 4625 } 4626 4627 static ExprResult 4628 PerformConstructorInitialization(Sema &S, 4629 const InitializedEntity &Entity, 4630 const InitializationKind &Kind, 4631 MultiExprArg Args, 4632 const InitializationSequence::Step& Step, 4633 bool &ConstructorInitRequiresZeroInit) { 4634 unsigned NumArgs = Args.size(); 4635 CXXConstructorDecl *Constructor 4636 = cast<CXXConstructorDecl>(Step.Function.Function); 4637 bool HadMultipleCandidates = Step.Function.HadMultipleCandidates; 4638 4639 // Build a call to the selected constructor. 4640 ASTOwningVector<Expr*> ConstructorArgs(S); 4641 SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid()) 4642 ? Kind.getEqualLoc() 4643 : Kind.getLocation(); 4644 4645 if (Kind.getKind() == InitializationKind::IK_Default) { 4646 // Force even a trivial, implicit default constructor to be 4647 // semantically checked. We do this explicitly because we don't build 4648 // the definition for completely trivial constructors. 4649 assert(Constructor->getParent() && "No parent class for constructor."); 4650 if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() && 4651 Constructor->isTrivial() && !Constructor->isUsed(false)) 4652 S.DefineImplicitDefaultConstructor(Loc, Constructor); 4653 } 4654 4655 ExprResult CurInit = S.Owned((Expr *)0); 4656 4657 // C++ [over.match.copy]p1: 4658 // - When initializing a temporary to be bound to the first parameter 4659 // of a constructor that takes a reference to possibly cv-qualified 4660 // T as its first argument, called with a single argument in the 4661 // context of direct-initialization, explicit conversion functions 4662 // are also considered. 4663 bool AllowExplicitConv = Kind.AllowExplicit() && !Kind.isCopyInit() && 4664 Args.size() == 1 && 4665 Constructor->isCopyOrMoveConstructor(); 4666 4667 // Determine the arguments required to actually perform the constructor 4668 // call. 4669 if (S.CompleteConstructorCall(Constructor, move(Args), 4670 Loc, ConstructorArgs, 4671 AllowExplicitConv)) 4672 return ExprError(); 4673 4674 4675 if (Entity.getKind() == InitializedEntity::EK_Temporary && 4676 (Kind.getKind() == InitializationKind::IK_DirectList || 4677 (NumArgs != 1 && // FIXME: Hack to work around cast weirdness 4678 (Kind.getKind() == InitializationKind::IK_Direct || 4679 Kind.getKind() == InitializationKind::IK_Value)))) { 4680 // An explicitly-constructed temporary, e.g., X(1, 2). 4681 unsigned NumExprs = ConstructorArgs.size(); 4682 Expr **Exprs = (Expr **)ConstructorArgs.take(); 4683 S.MarkFunctionReferenced(Loc, Constructor); 4684 S.DiagnoseUseOfDecl(Constructor, Loc); 4685 4686 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo(); 4687 if (!TSInfo) 4688 TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc); 4689 SourceRange ParenRange; 4690 if (Kind.getKind() != InitializationKind::IK_DirectList) 4691 ParenRange = Kind.getParenRange(); 4692 4693 CurInit = S.Owned(new (S.Context) CXXTemporaryObjectExpr(S.Context, 4694 Constructor, 4695 TSInfo, 4696 Exprs, 4697 NumExprs, 4698 ParenRange, 4699 HadMultipleCandidates, 4700 ConstructorInitRequiresZeroInit)); 4701 } else { 4702 CXXConstructExpr::ConstructionKind ConstructKind = 4703 CXXConstructExpr::CK_Complete; 4704 4705 if (Entity.getKind() == InitializedEntity::EK_Base) { 4706 ConstructKind = Entity.getBaseSpecifier()->isVirtual() ? 4707 CXXConstructExpr::CK_VirtualBase : 4708 CXXConstructExpr::CK_NonVirtualBase; 4709 } else if (Entity.getKind() == InitializedEntity::EK_Delegating) { 4710 ConstructKind = CXXConstructExpr::CK_Delegating; 4711 } 4712 4713 // Only get the parenthesis range if it is a direct construction. 4714 SourceRange parenRange = 4715 Kind.getKind() == InitializationKind::IK_Direct ? 4716 Kind.getParenRange() : SourceRange(); 4717 4718 // If the entity allows NRVO, mark the construction as elidable 4719 // unconditionally. 4720 if (Entity.allowsNRVO()) 4721 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 4722 Constructor, /*Elidable=*/true, 4723 move_arg(ConstructorArgs), 4724 HadMultipleCandidates, 4725 ConstructorInitRequiresZeroInit, 4726 ConstructKind, 4727 parenRange); 4728 else 4729 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 4730 Constructor, 4731 move_arg(ConstructorArgs), 4732 HadMultipleCandidates, 4733 ConstructorInitRequiresZeroInit, 4734 ConstructKind, 4735 parenRange); 4736 } 4737 if (CurInit.isInvalid()) 4738 return ExprError(); 4739 4740 // Only check access if all of that succeeded. 4741 S.CheckConstructorAccess(Loc, Constructor, Entity, 4742 Step.Function.FoundDecl.getAccess()); 4743 S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc); 4744 4745 if (shouldBindAsTemporary(Entity)) 4746 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 4747 4748 return move(CurInit); 4749 } 4750 4751 ExprResult 4752 InitializationSequence::Perform(Sema &S, 4753 const InitializedEntity &Entity, 4754 const InitializationKind &Kind, 4755 MultiExprArg Args, 4756 QualType *ResultType) { 4757 if (Failed()) { 4758 unsigned NumArgs = Args.size(); 4759 Diagnose(S, Entity, Kind, (Expr **)Args.release(), NumArgs); 4760 return ExprError(); 4761 } 4762 4763 if (getKind() == DependentSequence) { 4764 // If the declaration is a non-dependent, incomplete array type 4765 // that has an initializer, then its type will be completed once 4766 // the initializer is instantiated. 4767 if (ResultType && !Entity.getType()->isDependentType() && 4768 Args.size() == 1) { 4769 QualType DeclType = Entity.getType(); 4770 if (const IncompleteArrayType *ArrayT 4771 = S.Context.getAsIncompleteArrayType(DeclType)) { 4772 // FIXME: We don't currently have the ability to accurately 4773 // compute the length of an initializer list without 4774 // performing full type-checking of the initializer list 4775 // (since we have to determine where braces are implicitly 4776 // introduced and such). So, we fall back to making the array 4777 // type a dependently-sized array type with no specified 4778 // bound. 4779 if (isa<InitListExpr>((Expr *)Args.get()[0])) { 4780 SourceRange Brackets; 4781 4782 // Scavange the location of the brackets from the entity, if we can. 4783 if (DeclaratorDecl *DD = Entity.getDecl()) { 4784 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) { 4785 TypeLoc TL = TInfo->getTypeLoc(); 4786 if (IncompleteArrayTypeLoc *ArrayLoc 4787 = dyn_cast<IncompleteArrayTypeLoc>(&TL)) 4788 Brackets = ArrayLoc->getBracketsRange(); 4789 } 4790 } 4791 4792 *ResultType 4793 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(), 4794 /*NumElts=*/0, 4795 ArrayT->getSizeModifier(), 4796 ArrayT->getIndexTypeCVRQualifiers(), 4797 Brackets); 4798 } 4799 4800 } 4801 } 4802 if (Kind.getKind() == InitializationKind::IK_Direct && 4803 !Kind.isExplicitCast()) { 4804 // Rebuild the ParenListExpr. 4805 SourceRange ParenRange = Kind.getParenRange(); 4806 return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(), 4807 move(Args)); 4808 } 4809 assert(Kind.getKind() == InitializationKind::IK_Copy || 4810 Kind.isExplicitCast() || 4811 Kind.getKind() == InitializationKind::IK_DirectList); 4812 return ExprResult(Args.release()[0]); 4813 } 4814 4815 // No steps means no initialization. 4816 if (Steps.empty()) 4817 return S.Owned((Expr *)0); 4818 4819 QualType DestType = Entity.getType().getNonReferenceType(); 4820 // FIXME: Ugly hack around the fact that Entity.getType() is not 4821 // the same as Entity.getDecl()->getType() in cases involving type merging, 4822 // and we want latter when it makes sense. 4823 if (ResultType) 4824 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() : 4825 Entity.getType(); 4826 4827 ExprResult CurInit = S.Owned((Expr *)0); 4828 4829 // For initialization steps that start with a single initializer, 4830 // grab the only argument out the Args and place it into the "current" 4831 // initializer. 4832 switch (Steps.front().Kind) { 4833 case SK_ResolveAddressOfOverloadedFunction: 4834 case SK_CastDerivedToBaseRValue: 4835 case SK_CastDerivedToBaseXValue: 4836 case SK_CastDerivedToBaseLValue: 4837 case SK_BindReference: 4838 case SK_BindReferenceToTemporary: 4839 case SK_ExtraneousCopyToTemporary: 4840 case SK_UserConversion: 4841 case SK_QualificationConversionLValue: 4842 case SK_QualificationConversionXValue: 4843 case SK_QualificationConversionRValue: 4844 case SK_ConversionSequence: 4845 case SK_ListConstructorCall: 4846 case SK_ListInitialization: 4847 case SK_UnwrapInitList: 4848 case SK_RewrapInitList: 4849 case SK_CAssignment: 4850 case SK_StringInit: 4851 case SK_ObjCObjectConversion: 4852 case SK_ArrayInit: 4853 case SK_ParenthesizedArrayInit: 4854 case SK_PassByIndirectCopyRestore: 4855 case SK_PassByIndirectRestore: 4856 case SK_ProduceObjCObject: 4857 case SK_StdInitializerList: { 4858 assert(Args.size() == 1); 4859 CurInit = Args.get()[0]; 4860 if (!CurInit.get()) return ExprError(); 4861 break; 4862 } 4863 4864 case SK_ConstructorInitialization: 4865 case SK_ZeroInitialization: 4866 break; 4867 } 4868 4869 // Walk through the computed steps for the initialization sequence, 4870 // performing the specified conversions along the way. 4871 bool ConstructorInitRequiresZeroInit = false; 4872 for (step_iterator Step = step_begin(), StepEnd = step_end(); 4873 Step != StepEnd; ++Step) { 4874 if (CurInit.isInvalid()) 4875 return ExprError(); 4876 4877 QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType(); 4878 4879 switch (Step->Kind) { 4880 case SK_ResolveAddressOfOverloadedFunction: 4881 // Overload resolution determined which function invoke; update the 4882 // initializer to reflect that choice. 4883 S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl); 4884 S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()); 4885 CurInit = S.FixOverloadedFunctionReference(move(CurInit), 4886 Step->Function.FoundDecl, 4887 Step->Function.Function); 4888 break; 4889 4890 case SK_CastDerivedToBaseRValue: 4891 case SK_CastDerivedToBaseXValue: 4892 case SK_CastDerivedToBaseLValue: { 4893 // We have a derived-to-base cast that produces either an rvalue or an 4894 // lvalue. Perform that cast. 4895 4896 CXXCastPath BasePath; 4897 4898 // Casts to inaccessible base classes are allowed with C-style casts. 4899 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); 4900 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type, 4901 CurInit.get()->getLocStart(), 4902 CurInit.get()->getSourceRange(), 4903 &BasePath, IgnoreBaseAccess)) 4904 return ExprError(); 4905 4906 if (S.BasePathInvolvesVirtualBase(BasePath)) { 4907 QualType T = SourceType; 4908 if (const PointerType *Pointer = T->getAs<PointerType>()) 4909 T = Pointer->getPointeeType(); 4910 if (const RecordType *RecordTy = T->getAs<RecordType>()) 4911 S.MarkVTableUsed(CurInit.get()->getLocStart(), 4912 cast<CXXRecordDecl>(RecordTy->getDecl())); 4913 } 4914 4915 ExprValueKind VK = 4916 Step->Kind == SK_CastDerivedToBaseLValue ? 4917 VK_LValue : 4918 (Step->Kind == SK_CastDerivedToBaseXValue ? 4919 VK_XValue : 4920 VK_RValue); 4921 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, 4922 Step->Type, 4923 CK_DerivedToBase, 4924 CurInit.get(), 4925 &BasePath, VK)); 4926 break; 4927 } 4928 4929 case SK_BindReference: 4930 if (FieldDecl *BitField = CurInit.get()->getBitField()) { 4931 // References cannot bind to bit fields (C++ [dcl.init.ref]p5). 4932 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield) 4933 << Entity.getType().isVolatileQualified() 4934 << BitField->getDeclName() 4935 << CurInit.get()->getSourceRange(); 4936 S.Diag(BitField->getLocation(), diag::note_bitfield_decl); 4937 return ExprError(); 4938 } 4939 4940 if (CurInit.get()->refersToVectorElement()) { 4941 // References cannot bind to vector elements. 4942 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element) 4943 << Entity.getType().isVolatileQualified() 4944 << CurInit.get()->getSourceRange(); 4945 PrintInitLocationNote(S, Entity); 4946 return ExprError(); 4947 } 4948 4949 // Reference binding does not have any corresponding ASTs. 4950 4951 // Check exception specifications 4952 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType)) 4953 return ExprError(); 4954 4955 break; 4956 4957 case SK_BindReferenceToTemporary: 4958 // Check exception specifications 4959 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType)) 4960 return ExprError(); 4961 4962 // Materialize the temporary into memory. 4963 CurInit = new (S.Context) MaterializeTemporaryExpr( 4964 Entity.getType().getNonReferenceType(), 4965 CurInit.get(), 4966 Entity.getType()->isLValueReferenceType()); 4967 4968 // If we're binding to an Objective-C object that has lifetime, we 4969 // need cleanups. 4970 if (S.getLangOpts().ObjCAutoRefCount && 4971 CurInit.get()->getType()->isObjCLifetimeType()) 4972 S.ExprNeedsCleanups = true; 4973 4974 break; 4975 4976 case SK_ExtraneousCopyToTemporary: 4977 CurInit = CopyObject(S, Step->Type, Entity, move(CurInit), 4978 /*IsExtraneousCopy=*/true); 4979 break; 4980 4981 case SK_UserConversion: { 4982 // We have a user-defined conversion that invokes either a constructor 4983 // or a conversion function. 4984 CastKind CastKind; 4985 bool IsCopy = false; 4986 FunctionDecl *Fn = Step->Function.Function; 4987 DeclAccessPair FoundFn = Step->Function.FoundDecl; 4988 bool HadMultipleCandidates = Step->Function.HadMultipleCandidates; 4989 bool CreatedObject = false; 4990 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) { 4991 // Build a call to the selected constructor. 4992 ASTOwningVector<Expr*> ConstructorArgs(S); 4993 SourceLocation Loc = CurInit.get()->getLocStart(); 4994 CurInit.release(); // Ownership transferred into MultiExprArg, below. 4995 4996 // Determine the arguments required to actually perform the constructor 4997 // call. 4998 Expr *Arg = CurInit.get(); 4999 if (S.CompleteConstructorCall(Constructor, 5000 MultiExprArg(&Arg, 1), 5001 Loc, ConstructorArgs)) 5002 return ExprError(); 5003 5004 // Build an expression that constructs a temporary. 5005 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor, 5006 move_arg(ConstructorArgs), 5007 HadMultipleCandidates, 5008 /*ZeroInit*/ false, 5009 CXXConstructExpr::CK_Complete, 5010 SourceRange()); 5011 if (CurInit.isInvalid()) 5012 return ExprError(); 5013 5014 S.CheckConstructorAccess(Kind.getLocation(), Constructor, Entity, 5015 FoundFn.getAccess()); 5016 S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()); 5017 5018 CastKind = CK_ConstructorConversion; 5019 QualType Class = S.Context.getTypeDeclType(Constructor->getParent()); 5020 if (S.Context.hasSameUnqualifiedType(SourceType, Class) || 5021 S.IsDerivedFrom(SourceType, Class)) 5022 IsCopy = true; 5023 5024 CreatedObject = true; 5025 } else { 5026 // Build a call to the conversion function. 5027 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn); 5028 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), 0, 5029 FoundFn); 5030 S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()); 5031 5032 // FIXME: Should we move this initialization into a separate 5033 // derived-to-base conversion? I believe the answer is "no", because 5034 // we don't want to turn off access control here for c-style casts. 5035 ExprResult CurInitExprRes = 5036 S.PerformObjectArgumentInitialization(CurInit.take(), /*Qualifier=*/0, 5037 FoundFn, Conversion); 5038 if(CurInitExprRes.isInvalid()) 5039 return ExprError(); 5040 CurInit = move(CurInitExprRes); 5041 5042 // Build the actual call to the conversion function. 5043 CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion, 5044 HadMultipleCandidates); 5045 if (CurInit.isInvalid() || !CurInit.get()) 5046 return ExprError(); 5047 5048 CastKind = CK_UserDefinedConversion; 5049 5050 CreatedObject = Conversion->getResultType()->isRecordType(); 5051 } 5052 5053 bool RequiresCopy = !IsCopy && !isReferenceBinding(Steps.back()); 5054 bool MaybeBindToTemp = RequiresCopy || shouldBindAsTemporary(Entity); 5055 5056 if (!MaybeBindToTemp && CreatedObject && shouldDestroyTemporary(Entity)) { 5057 QualType T = CurInit.get()->getType(); 5058 if (const RecordType *Record = T->getAs<RecordType>()) { 5059 CXXDestructorDecl *Destructor 5060 = S.LookupDestructor(cast<CXXRecordDecl>(Record->getDecl())); 5061 S.CheckDestructorAccess(CurInit.get()->getLocStart(), Destructor, 5062 S.PDiag(diag::err_access_dtor_temp) << T); 5063 S.MarkFunctionReferenced(CurInit.get()->getLocStart(), Destructor); 5064 S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getLocStart()); 5065 } 5066 } 5067 5068 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, 5069 CurInit.get()->getType(), 5070 CastKind, CurInit.get(), 0, 5071 CurInit.get()->getValueKind())); 5072 if (MaybeBindToTemp) 5073 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 5074 if (RequiresCopy) 5075 CurInit = CopyObject(S, Entity.getType().getNonReferenceType(), Entity, 5076 move(CurInit), /*IsExtraneousCopy=*/false); 5077 break; 5078 } 5079 5080 case SK_QualificationConversionLValue: 5081 case SK_QualificationConversionXValue: 5082 case SK_QualificationConversionRValue: { 5083 // Perform a qualification conversion; these can never go wrong. 5084 ExprValueKind VK = 5085 Step->Kind == SK_QualificationConversionLValue ? 5086 VK_LValue : 5087 (Step->Kind == SK_QualificationConversionXValue ? 5088 VK_XValue : 5089 VK_RValue); 5090 CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, CK_NoOp, VK); 5091 break; 5092 } 5093 5094 case SK_ConversionSequence: { 5095 Sema::CheckedConversionKind CCK 5096 = Kind.isCStyleCast()? Sema::CCK_CStyleCast 5097 : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast 5098 : Kind.isExplicitCast()? Sema::CCK_OtherCast 5099 : Sema::CCK_ImplicitConversion; 5100 ExprResult CurInitExprRes = 5101 S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS, 5102 getAssignmentAction(Entity), CCK); 5103 if (CurInitExprRes.isInvalid()) 5104 return ExprError(); 5105 CurInit = move(CurInitExprRes); 5106 break; 5107 } 5108 5109 case SK_ListInitialization: { 5110 InitListExpr *InitList = cast<InitListExpr>(CurInit.get()); 5111 // Hack: We must pass *ResultType if available in order to set the type 5112 // of arrays, e.g. in 'int ar[] = {1, 2, 3};'. 5113 // But in 'const X &x = {1, 2, 3};' we're supposed to initialize a 5114 // temporary, not a reference, so we should pass Ty. 5115 // Worst case: 'const int (&arref)[] = {1, 2, 3};'. 5116 // Since this step is never used for a reference directly, we explicitly 5117 // unwrap references here and rewrap them afterwards. 5118 // We also need to create a InitializeTemporary entity for this. 5119 QualType Ty = ResultType ? ResultType->getNonReferenceType() : Step->Type; 5120 bool IsTemporary = Entity.getType()->isReferenceType(); 5121 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty); 5122 InitListChecker PerformInitList(S, IsTemporary ? TempEntity : Entity, 5123 InitList, Ty, /*VerifyOnly=*/false, 5124 Kind.getKind() != InitializationKind::IK_DirectList || 5125 !S.getLangOpts().CPlusPlus0x); 5126 if (PerformInitList.HadError()) 5127 return ExprError(); 5128 5129 if (ResultType) { 5130 if ((*ResultType)->isRValueReferenceType()) 5131 Ty = S.Context.getRValueReferenceType(Ty); 5132 else if ((*ResultType)->isLValueReferenceType()) 5133 Ty = S.Context.getLValueReferenceType(Ty, 5134 (*ResultType)->getAs<LValueReferenceType>()->isSpelledAsLValue()); 5135 *ResultType = Ty; 5136 } 5137 5138 InitListExpr *StructuredInitList = 5139 PerformInitList.getFullyStructuredList(); 5140 CurInit.release(); 5141 CurInit = S.Owned(StructuredInitList); 5142 break; 5143 } 5144 5145 case SK_ListConstructorCall: { 5146 // When an initializer list is passed for a parameter of type "reference 5147 // to object", we don't get an EK_Temporary entity, but instead an 5148 // EK_Parameter entity with reference type. 5149 // FIXME: This is a hack. What we really should do is create a user 5150 // conversion step for this case, but this makes it considerably more 5151 // complicated. For now, this will do. 5152 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary( 5153 Entity.getType().getNonReferenceType()); 5154 bool UseTemporary = Entity.getType()->isReferenceType(); 5155 InitListExpr *InitList = cast<InitListExpr>(CurInit.get()); 5156 MultiExprArg Arg(InitList->getInits(), InitList->getNumInits()); 5157 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity : 5158 Entity, 5159 Kind, move(Arg), *Step, 5160 ConstructorInitRequiresZeroInit); 5161 break; 5162 } 5163 5164 case SK_UnwrapInitList: 5165 CurInit = S.Owned(cast<InitListExpr>(CurInit.take())->getInit(0)); 5166 break; 5167 5168 case SK_RewrapInitList: { 5169 Expr *E = CurInit.take(); 5170 InitListExpr *Syntactic = Step->WrappingSyntacticList; 5171 InitListExpr *ILE = new (S.Context) InitListExpr(S.Context, 5172 Syntactic->getLBraceLoc(), &E, 1, Syntactic->getRBraceLoc()); 5173 ILE->setSyntacticForm(Syntactic); 5174 ILE->setType(E->getType()); 5175 ILE->setValueKind(E->getValueKind()); 5176 CurInit = S.Owned(ILE); 5177 break; 5178 } 5179 5180 case SK_ConstructorInitialization: { 5181 // When an initializer list is passed for a parameter of type "reference 5182 // to object", we don't get an EK_Temporary entity, but instead an 5183 // EK_Parameter entity with reference type. 5184 // FIXME: This is a hack. What we really should do is create a user 5185 // conversion step for this case, but this makes it considerably more 5186 // complicated. For now, this will do. 5187 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary( 5188 Entity.getType().getNonReferenceType()); 5189 bool UseTemporary = Entity.getType()->isReferenceType(); 5190 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity 5191 : Entity, 5192 Kind, move(Args), *Step, 5193 ConstructorInitRequiresZeroInit); 5194 break; 5195 } 5196 5197 case SK_ZeroInitialization: { 5198 step_iterator NextStep = Step; 5199 ++NextStep; 5200 if (NextStep != StepEnd && 5201 NextStep->Kind == SK_ConstructorInitialization) { 5202 // The need for zero-initialization is recorded directly into 5203 // the call to the object's constructor within the next step. 5204 ConstructorInitRequiresZeroInit = true; 5205 } else if (Kind.getKind() == InitializationKind::IK_Value && 5206 S.getLangOpts().CPlusPlus && 5207 !Kind.isImplicitValueInit()) { 5208 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo(); 5209 if (!TSInfo) 5210 TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type, 5211 Kind.getRange().getBegin()); 5212 5213 CurInit = S.Owned(new (S.Context) CXXScalarValueInitExpr( 5214 TSInfo->getType().getNonLValueExprType(S.Context), 5215 TSInfo, 5216 Kind.getRange().getEnd())); 5217 } else { 5218 CurInit = S.Owned(new (S.Context) ImplicitValueInitExpr(Step->Type)); 5219 } 5220 break; 5221 } 5222 5223 case SK_CAssignment: { 5224 QualType SourceType = CurInit.get()->getType(); 5225 ExprResult Result = move(CurInit); 5226 Sema::AssignConvertType ConvTy = 5227 S.CheckSingleAssignmentConstraints(Step->Type, Result); 5228 if (Result.isInvalid()) 5229 return ExprError(); 5230 CurInit = move(Result); 5231 5232 // If this is a call, allow conversion to a transparent union. 5233 ExprResult CurInitExprRes = move(CurInit); 5234 if (ConvTy != Sema::Compatible && 5235 Entity.getKind() == InitializedEntity::EK_Parameter && 5236 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes) 5237 == Sema::Compatible) 5238 ConvTy = Sema::Compatible; 5239 if (CurInitExprRes.isInvalid()) 5240 return ExprError(); 5241 CurInit = move(CurInitExprRes); 5242 5243 bool Complained; 5244 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(), 5245 Step->Type, SourceType, 5246 CurInit.get(), 5247 getAssignmentAction(Entity), 5248 &Complained)) { 5249 PrintInitLocationNote(S, Entity); 5250 return ExprError(); 5251 } else if (Complained) 5252 PrintInitLocationNote(S, Entity); 5253 break; 5254 } 5255 5256 case SK_StringInit: { 5257 QualType Ty = Step->Type; 5258 CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty, 5259 S.Context.getAsArrayType(Ty), S); 5260 break; 5261 } 5262 5263 case SK_ObjCObjectConversion: 5264 CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, 5265 CK_ObjCObjectLValueCast, 5266 CurInit.get()->getValueKind()); 5267 break; 5268 5269 case SK_ArrayInit: 5270 // Okay: we checked everything before creating this step. Note that 5271 // this is a GNU extension. 5272 S.Diag(Kind.getLocation(), diag::ext_array_init_copy) 5273 << Step->Type << CurInit.get()->getType() 5274 << CurInit.get()->getSourceRange(); 5275 5276 // If the destination type is an incomplete array type, update the 5277 // type accordingly. 5278 if (ResultType) { 5279 if (const IncompleteArrayType *IncompleteDest 5280 = S.Context.getAsIncompleteArrayType(Step->Type)) { 5281 if (const ConstantArrayType *ConstantSource 5282 = S.Context.getAsConstantArrayType(CurInit.get()->getType())) { 5283 *ResultType = S.Context.getConstantArrayType( 5284 IncompleteDest->getElementType(), 5285 ConstantSource->getSize(), 5286 ArrayType::Normal, 0); 5287 } 5288 } 5289 } 5290 break; 5291 5292 case SK_ParenthesizedArrayInit: 5293 // Okay: we checked everything before creating this step. Note that 5294 // this is a GNU extension. 5295 S.Diag(Kind.getLocation(), diag::ext_array_init_parens) 5296 << CurInit.get()->getSourceRange(); 5297 break; 5298 5299 case SK_PassByIndirectCopyRestore: 5300 case SK_PassByIndirectRestore: 5301 checkIndirectCopyRestoreSource(S, CurInit.get()); 5302 CurInit = S.Owned(new (S.Context) 5303 ObjCIndirectCopyRestoreExpr(CurInit.take(), Step->Type, 5304 Step->Kind == SK_PassByIndirectCopyRestore)); 5305 break; 5306 5307 case SK_ProduceObjCObject: 5308 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, Step->Type, 5309 CK_ARCProduceObject, 5310 CurInit.take(), 0, VK_RValue)); 5311 break; 5312 5313 case SK_StdInitializerList: { 5314 QualType Dest = Step->Type; 5315 QualType E; 5316 bool Success = S.isStdInitializerList(Dest, &E); 5317 (void)Success; 5318 assert(Success && "Destination type changed?"); 5319 5320 // If the element type has a destructor, check it. 5321 if (CXXRecordDecl *RD = E->getAsCXXRecordDecl()) { 5322 if (!RD->hasIrrelevantDestructor()) { 5323 if (CXXDestructorDecl *Destructor = S.LookupDestructor(RD)) { 5324 S.MarkFunctionReferenced(Kind.getLocation(), Destructor); 5325 S.CheckDestructorAccess(Kind.getLocation(), Destructor, 5326 S.PDiag(diag::err_access_dtor_temp) << E); 5327 S.DiagnoseUseOfDecl(Destructor, Kind.getLocation()); 5328 } 5329 } 5330 } 5331 5332 InitListExpr *ILE = cast<InitListExpr>(CurInit.take()); 5333 unsigned NumInits = ILE->getNumInits(); 5334 SmallVector<Expr*, 16> Converted(NumInits); 5335 InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( 5336 S.Context.getConstantArrayType(E, 5337 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), 5338 NumInits), 5339 ArrayType::Normal, 0)); 5340 InitializedEntity Element =InitializedEntity::InitializeElement(S.Context, 5341 0, HiddenArray); 5342 for (unsigned i = 0; i < NumInits; ++i) { 5343 Element.setElementIndex(i); 5344 ExprResult Init = S.Owned(ILE->getInit(i)); 5345 ExprResult Res = S.PerformCopyInitialization(Element, 5346 Init.get()->getExprLoc(), 5347 Init); 5348 assert(!Res.isInvalid() && "Result changed since try phase."); 5349 Converted[i] = Res.take(); 5350 } 5351 InitListExpr *Semantic = new (S.Context) 5352 InitListExpr(S.Context, ILE->getLBraceLoc(), 5353 Converted.data(), NumInits, ILE->getRBraceLoc()); 5354 Semantic->setSyntacticForm(ILE); 5355 Semantic->setType(Dest); 5356 Semantic->setInitializesStdInitializerList(); 5357 CurInit = S.Owned(Semantic); 5358 break; 5359 } 5360 } 5361 } 5362 5363 // Diagnose non-fatal problems with the completed initialization. 5364 if (Entity.getKind() == InitializedEntity::EK_Member && 5365 cast<FieldDecl>(Entity.getDecl())->isBitField()) 5366 S.CheckBitFieldInitialization(Kind.getLocation(), 5367 cast<FieldDecl>(Entity.getDecl()), 5368 CurInit.get()); 5369 5370 return move(CurInit); 5371 } 5372 5373 //===----------------------------------------------------------------------===// 5374 // Diagnose initialization failures 5375 //===----------------------------------------------------------------------===// 5376 bool InitializationSequence::Diagnose(Sema &S, 5377 const InitializedEntity &Entity, 5378 const InitializationKind &Kind, 5379 Expr **Args, unsigned NumArgs) { 5380 if (!Failed()) 5381 return false; 5382 5383 QualType DestType = Entity.getType(); 5384 switch (Failure) { 5385 case FK_TooManyInitsForReference: 5386 // FIXME: Customize for the initialized entity? 5387 if (NumArgs == 0) 5388 S.Diag(Kind.getLocation(), diag::err_reference_without_init) 5389 << DestType.getNonReferenceType(); 5390 else // FIXME: diagnostic below could be better! 5391 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits) 5392 << SourceRange(Args[0]->getLocStart(), Args[NumArgs - 1]->getLocEnd()); 5393 break; 5394 5395 case FK_ArrayNeedsInitList: 5396 case FK_ArrayNeedsInitListOrStringLiteral: 5397 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) 5398 << (Failure == FK_ArrayNeedsInitListOrStringLiteral); 5399 break; 5400 5401 case FK_ArrayTypeMismatch: 5402 case FK_NonConstantArrayInit: 5403 S.Diag(Kind.getLocation(), 5404 (Failure == FK_ArrayTypeMismatch 5405 ? diag::err_array_init_different_type 5406 : diag::err_array_init_non_constant_array)) 5407 << DestType.getNonReferenceType() 5408 << Args[0]->getType() 5409 << Args[0]->getSourceRange(); 5410 break; 5411 5412 case FK_VariableLengthArrayHasInitializer: 5413 S.Diag(Kind.getLocation(), diag::err_variable_object_no_init) 5414 << Args[0]->getSourceRange(); 5415 break; 5416 5417 case FK_AddressOfOverloadFailed: { 5418 DeclAccessPair Found; 5419 S.ResolveAddressOfOverloadedFunction(Args[0], 5420 DestType.getNonReferenceType(), 5421 true, 5422 Found); 5423 break; 5424 } 5425 5426 case FK_ReferenceInitOverloadFailed: 5427 case FK_UserConversionOverloadFailed: 5428 switch (FailedOverloadResult) { 5429 case OR_Ambiguous: 5430 if (Failure == FK_UserConversionOverloadFailed) 5431 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition) 5432 << Args[0]->getType() << DestType 5433 << Args[0]->getSourceRange(); 5434 else 5435 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous) 5436 << DestType << Args[0]->getType() 5437 << Args[0]->getSourceRange(); 5438 5439 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, 5440 llvm::makeArrayRef(Args, NumArgs)); 5441 break; 5442 5443 case OR_No_Viable_Function: 5444 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition) 5445 << Args[0]->getType() << DestType.getNonReferenceType() 5446 << Args[0]->getSourceRange(); 5447 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, 5448 llvm::makeArrayRef(Args, NumArgs)); 5449 break; 5450 5451 case OR_Deleted: { 5452 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function) 5453 << Args[0]->getType() << DestType.getNonReferenceType() 5454 << Args[0]->getSourceRange(); 5455 OverloadCandidateSet::iterator Best; 5456 OverloadingResult Ovl 5457 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best, 5458 true); 5459 if (Ovl == OR_Deleted) { 5460 S.NoteDeletedFunction(Best->Function); 5461 } else { 5462 llvm_unreachable("Inconsistent overload resolution?"); 5463 } 5464 break; 5465 } 5466 5467 case OR_Success: 5468 llvm_unreachable("Conversion did not fail!"); 5469 } 5470 break; 5471 5472 case FK_NonConstLValueReferenceBindingToTemporary: 5473 if (isa<InitListExpr>(Args[0])) { 5474 S.Diag(Kind.getLocation(), 5475 diag::err_lvalue_reference_bind_to_initlist) 5476 << DestType.getNonReferenceType().isVolatileQualified() 5477 << DestType.getNonReferenceType() 5478 << Args[0]->getSourceRange(); 5479 break; 5480 } 5481 // Intentional fallthrough 5482 5483 case FK_NonConstLValueReferenceBindingToUnrelated: 5484 S.Diag(Kind.getLocation(), 5485 Failure == FK_NonConstLValueReferenceBindingToTemporary 5486 ? diag::err_lvalue_reference_bind_to_temporary 5487 : diag::err_lvalue_reference_bind_to_unrelated) 5488 << DestType.getNonReferenceType().isVolatileQualified() 5489 << DestType.getNonReferenceType() 5490 << Args[0]->getType() 5491 << Args[0]->getSourceRange(); 5492 break; 5493 5494 case FK_RValueReferenceBindingToLValue: 5495 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref) 5496 << DestType.getNonReferenceType() << Args[0]->getType() 5497 << Args[0]->getSourceRange(); 5498 break; 5499 5500 case FK_ReferenceInitDropsQualifiers: 5501 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals) 5502 << DestType.getNonReferenceType() 5503 << Args[0]->getType() 5504 << Args[0]->getSourceRange(); 5505 break; 5506 5507 case FK_ReferenceInitFailed: 5508 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed) 5509 << DestType.getNonReferenceType() 5510 << Args[0]->isLValue() 5511 << Args[0]->getType() 5512 << Args[0]->getSourceRange(); 5513 if (DestType.getNonReferenceType()->isObjCObjectPointerType() && 5514 Args[0]->getType()->isObjCObjectPointerType()) 5515 S.EmitRelatedResultTypeNote(Args[0]); 5516 break; 5517 5518 case FK_ConversionFailed: { 5519 QualType FromType = Args[0]->getType(); 5520 PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed) 5521 << (int)Entity.getKind() 5522 << DestType 5523 << Args[0]->isLValue() 5524 << FromType 5525 << Args[0]->getSourceRange(); 5526 S.HandleFunctionTypeMismatch(PDiag, FromType, DestType); 5527 S.Diag(Kind.getLocation(), PDiag); 5528 if (DestType.getNonReferenceType()->isObjCObjectPointerType() && 5529 Args[0]->getType()->isObjCObjectPointerType()) 5530 S.EmitRelatedResultTypeNote(Args[0]); 5531 break; 5532 } 5533 5534 case FK_ConversionFromPropertyFailed: 5535 // No-op. This error has already been reported. 5536 break; 5537 5538 case FK_TooManyInitsForScalar: { 5539 SourceRange R; 5540 5541 if (InitListExpr *InitList = dyn_cast<InitListExpr>(Args[0])) 5542 R = SourceRange(InitList->getInit(0)->getLocEnd(), 5543 InitList->getLocEnd()); 5544 else 5545 R = SourceRange(Args[0]->getLocEnd(), Args[NumArgs - 1]->getLocEnd()); 5546 5547 R.setBegin(S.PP.getLocForEndOfToken(R.getBegin())); 5548 if (Kind.isCStyleOrFunctionalCast()) 5549 S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg) 5550 << R; 5551 else 5552 S.Diag(Kind.getLocation(), diag::err_excess_initializers) 5553 << /*scalar=*/2 << R; 5554 break; 5555 } 5556 5557 case FK_ReferenceBindingToInitList: 5558 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list) 5559 << DestType.getNonReferenceType() << Args[0]->getSourceRange(); 5560 break; 5561 5562 case FK_InitListBadDestinationType: 5563 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type) 5564 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange(); 5565 break; 5566 5567 case FK_ListConstructorOverloadFailed: 5568 case FK_ConstructorOverloadFailed: { 5569 SourceRange ArgsRange; 5570 if (NumArgs) 5571 ArgsRange = SourceRange(Args[0]->getLocStart(), 5572 Args[NumArgs - 1]->getLocEnd()); 5573 5574 if (Failure == FK_ListConstructorOverloadFailed) { 5575 assert(NumArgs == 1 && "List construction from other than 1 argument."); 5576 InitListExpr *InitList = cast<InitListExpr>(Args[0]); 5577 Args = InitList->getInits(); 5578 NumArgs = InitList->getNumInits(); 5579 } 5580 5581 // FIXME: Using "DestType" for the entity we're printing is probably 5582 // bad. 5583 switch (FailedOverloadResult) { 5584 case OR_Ambiguous: 5585 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init) 5586 << DestType << ArgsRange; 5587 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, 5588 llvm::makeArrayRef(Args, NumArgs)); 5589 break; 5590 5591 case OR_No_Viable_Function: 5592 if (Kind.getKind() == InitializationKind::IK_Default && 5593 (Entity.getKind() == InitializedEntity::EK_Base || 5594 Entity.getKind() == InitializedEntity::EK_Member) && 5595 isa<CXXConstructorDecl>(S.CurContext)) { 5596 // This is implicit default initialization of a member or 5597 // base within a constructor. If no viable function was 5598 // found, notify the user that she needs to explicitly 5599 // initialize this base/member. 5600 CXXConstructorDecl *Constructor 5601 = cast<CXXConstructorDecl>(S.CurContext); 5602 if (Entity.getKind() == InitializedEntity::EK_Base) { 5603 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 5604 << Constructor->isImplicit() 5605 << S.Context.getTypeDeclType(Constructor->getParent()) 5606 << /*base=*/0 5607 << Entity.getType(); 5608 5609 RecordDecl *BaseDecl 5610 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>() 5611 ->getDecl(); 5612 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl) 5613 << S.Context.getTagDeclType(BaseDecl); 5614 } else { 5615 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 5616 << Constructor->isImplicit() 5617 << S.Context.getTypeDeclType(Constructor->getParent()) 5618 << /*member=*/1 5619 << Entity.getName(); 5620 S.Diag(Entity.getDecl()->getLocation(), diag::note_field_decl); 5621 5622 if (const RecordType *Record 5623 = Entity.getType()->getAs<RecordType>()) 5624 S.Diag(Record->getDecl()->getLocation(), 5625 diag::note_previous_decl) 5626 << S.Context.getTagDeclType(Record->getDecl()); 5627 } 5628 break; 5629 } 5630 5631 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init) 5632 << DestType << ArgsRange; 5633 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, 5634 llvm::makeArrayRef(Args, NumArgs)); 5635 break; 5636 5637 case OR_Deleted: { 5638 OverloadCandidateSet::iterator Best; 5639 OverloadingResult Ovl 5640 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best); 5641 if (Ovl != OR_Deleted) { 5642 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) 5643 << true << DestType << ArgsRange; 5644 llvm_unreachable("Inconsistent overload resolution?"); 5645 break; 5646 } 5647 5648 // If this is a defaulted or implicitly-declared function, then 5649 // it was implicitly deleted. Make it clear that the deletion was 5650 // implicit. 5651 if (S.isImplicitlyDeleted(Best->Function)) 5652 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init) 5653 << S.getSpecialMember(cast<CXXMethodDecl>(Best->Function)) 5654 << DestType << ArgsRange; 5655 else 5656 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) 5657 << true << DestType << ArgsRange; 5658 5659 S.NoteDeletedFunction(Best->Function); 5660 break; 5661 } 5662 5663 case OR_Success: 5664 llvm_unreachable("Conversion did not fail!"); 5665 } 5666 } 5667 break; 5668 5669 case FK_DefaultInitOfConst: 5670 if (Entity.getKind() == InitializedEntity::EK_Member && 5671 isa<CXXConstructorDecl>(S.CurContext)) { 5672 // This is implicit default-initialization of a const member in 5673 // a constructor. Complain that it needs to be explicitly 5674 // initialized. 5675 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext); 5676 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor) 5677 << Constructor->isImplicit() 5678 << S.Context.getTypeDeclType(Constructor->getParent()) 5679 << /*const=*/1 5680 << Entity.getName(); 5681 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl) 5682 << Entity.getName(); 5683 } else { 5684 S.Diag(Kind.getLocation(), diag::err_default_init_const) 5685 << DestType << (bool)DestType->getAs<RecordType>(); 5686 } 5687 break; 5688 5689 case FK_Incomplete: 5690 S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType, 5691 diag::err_init_incomplete_type); 5692 break; 5693 5694 case FK_ListInitializationFailed: { 5695 // Run the init list checker again to emit diagnostics. 5696 InitListExpr* InitList = cast<InitListExpr>(Args[0]); 5697 QualType DestType = Entity.getType(); 5698 InitListChecker DiagnoseInitList(S, Entity, InitList, 5699 DestType, /*VerifyOnly=*/false, 5700 Kind.getKind() != InitializationKind::IK_DirectList || 5701 !S.getLangOpts().CPlusPlus0x); 5702 assert(DiagnoseInitList.HadError() && 5703 "Inconsistent init list check result."); 5704 break; 5705 } 5706 5707 case FK_PlaceholderType: { 5708 // FIXME: Already diagnosed! 5709 break; 5710 } 5711 5712 case FK_InitListElementCopyFailure: { 5713 // Try to perform all copies again. 5714 InitListExpr* InitList = cast<InitListExpr>(Args[0]); 5715 unsigned NumInits = InitList->getNumInits(); 5716 QualType DestType = Entity.getType(); 5717 QualType E; 5718 bool Success = S.isStdInitializerList(DestType, &E); 5719 (void)Success; 5720 assert(Success && "Where did the std::initializer_list go?"); 5721 InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( 5722 S.Context.getConstantArrayType(E, 5723 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), 5724 NumInits), 5725 ArrayType::Normal, 0)); 5726 InitializedEntity Element = InitializedEntity::InitializeElement(S.Context, 5727 0, HiddenArray); 5728 // Show at most 3 errors. Otherwise, you'd get a lot of errors for errors 5729 // where the init list type is wrong, e.g. 5730 // std::initializer_list<void*> list = { 1, 2, 3, 4, 5, 6, 7, 8 }; 5731 // FIXME: Emit a note if we hit the limit? 5732 int ErrorCount = 0; 5733 for (unsigned i = 0; i < NumInits && ErrorCount < 3; ++i) { 5734 Element.setElementIndex(i); 5735 ExprResult Init = S.Owned(InitList->getInit(i)); 5736 if (S.PerformCopyInitialization(Element, Init.get()->getExprLoc(), Init) 5737 .isInvalid()) 5738 ++ErrorCount; 5739 } 5740 break; 5741 } 5742 5743 case FK_ExplicitConstructor: { 5744 S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor) 5745 << Args[0]->getSourceRange(); 5746 OverloadCandidateSet::iterator Best; 5747 OverloadingResult Ovl 5748 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best); 5749 (void)Ovl; 5750 assert(Ovl == OR_Success && "Inconsistent overload resolution"); 5751 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function); 5752 S.Diag(CtorDecl->getLocation(), diag::note_constructor_declared_here); 5753 break; 5754 } 5755 } 5756 5757 PrintInitLocationNote(S, Entity); 5758 return true; 5759 } 5760 5761 void InitializationSequence::dump(raw_ostream &OS) const { 5762 switch (SequenceKind) { 5763 case FailedSequence: { 5764 OS << "Failed sequence: "; 5765 switch (Failure) { 5766 case FK_TooManyInitsForReference: 5767 OS << "too many initializers for reference"; 5768 break; 5769 5770 case FK_ArrayNeedsInitList: 5771 OS << "array requires initializer list"; 5772 break; 5773 5774 case FK_ArrayNeedsInitListOrStringLiteral: 5775 OS << "array requires initializer list or string literal"; 5776 break; 5777 5778 case FK_ArrayTypeMismatch: 5779 OS << "array type mismatch"; 5780 break; 5781 5782 case FK_NonConstantArrayInit: 5783 OS << "non-constant array initializer"; 5784 break; 5785 5786 case FK_AddressOfOverloadFailed: 5787 OS << "address of overloaded function failed"; 5788 break; 5789 5790 case FK_ReferenceInitOverloadFailed: 5791 OS << "overload resolution for reference initialization failed"; 5792 break; 5793 5794 case FK_NonConstLValueReferenceBindingToTemporary: 5795 OS << "non-const lvalue reference bound to temporary"; 5796 break; 5797 5798 case FK_NonConstLValueReferenceBindingToUnrelated: 5799 OS << "non-const lvalue reference bound to unrelated type"; 5800 break; 5801 5802 case FK_RValueReferenceBindingToLValue: 5803 OS << "rvalue reference bound to an lvalue"; 5804 break; 5805 5806 case FK_ReferenceInitDropsQualifiers: 5807 OS << "reference initialization drops qualifiers"; 5808 break; 5809 5810 case FK_ReferenceInitFailed: 5811 OS << "reference initialization failed"; 5812 break; 5813 5814 case FK_ConversionFailed: 5815 OS << "conversion failed"; 5816 break; 5817 5818 case FK_ConversionFromPropertyFailed: 5819 OS << "conversion from property failed"; 5820 break; 5821 5822 case FK_TooManyInitsForScalar: 5823 OS << "too many initializers for scalar"; 5824 break; 5825 5826 case FK_ReferenceBindingToInitList: 5827 OS << "referencing binding to initializer list"; 5828 break; 5829 5830 case FK_InitListBadDestinationType: 5831 OS << "initializer list for non-aggregate, non-scalar type"; 5832 break; 5833 5834 case FK_UserConversionOverloadFailed: 5835 OS << "overloading failed for user-defined conversion"; 5836 break; 5837 5838 case FK_ConstructorOverloadFailed: 5839 OS << "constructor overloading failed"; 5840 break; 5841 5842 case FK_DefaultInitOfConst: 5843 OS << "default initialization of a const variable"; 5844 break; 5845 5846 case FK_Incomplete: 5847 OS << "initialization of incomplete type"; 5848 break; 5849 5850 case FK_ListInitializationFailed: 5851 OS << "list initialization checker failure"; 5852 break; 5853 5854 case FK_VariableLengthArrayHasInitializer: 5855 OS << "variable length array has an initializer"; 5856 break; 5857 5858 case FK_PlaceholderType: 5859 OS << "initializer expression isn't contextually valid"; 5860 break; 5861 5862 case FK_ListConstructorOverloadFailed: 5863 OS << "list constructor overloading failed"; 5864 break; 5865 5866 case FK_InitListElementCopyFailure: 5867 OS << "copy construction of initializer list element failed"; 5868 break; 5869 5870 case FK_ExplicitConstructor: 5871 OS << "list copy initialization chose explicit constructor"; 5872 break; 5873 } 5874 OS << '\n'; 5875 return; 5876 } 5877 5878 case DependentSequence: 5879 OS << "Dependent sequence\n"; 5880 return; 5881 5882 case NormalSequence: 5883 OS << "Normal sequence: "; 5884 break; 5885 } 5886 5887 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) { 5888 if (S != step_begin()) { 5889 OS << " -> "; 5890 } 5891 5892 switch (S->Kind) { 5893 case SK_ResolveAddressOfOverloadedFunction: 5894 OS << "resolve address of overloaded function"; 5895 break; 5896 5897 case SK_CastDerivedToBaseRValue: 5898 OS << "derived-to-base case (rvalue" << S->Type.getAsString() << ")"; 5899 break; 5900 5901 case SK_CastDerivedToBaseXValue: 5902 OS << "derived-to-base case (xvalue" << S->Type.getAsString() << ")"; 5903 break; 5904 5905 case SK_CastDerivedToBaseLValue: 5906 OS << "derived-to-base case (lvalue" << S->Type.getAsString() << ")"; 5907 break; 5908 5909 case SK_BindReference: 5910 OS << "bind reference to lvalue"; 5911 break; 5912 5913 case SK_BindReferenceToTemporary: 5914 OS << "bind reference to a temporary"; 5915 break; 5916 5917 case SK_ExtraneousCopyToTemporary: 5918 OS << "extraneous C++03 copy to temporary"; 5919 break; 5920 5921 case SK_UserConversion: 5922 OS << "user-defined conversion via " << *S->Function.Function; 5923 break; 5924 5925 case SK_QualificationConversionRValue: 5926 OS << "qualification conversion (rvalue)"; 5927 break; 5928 5929 case SK_QualificationConversionXValue: 5930 OS << "qualification conversion (xvalue)"; 5931 break; 5932 5933 case SK_QualificationConversionLValue: 5934 OS << "qualification conversion (lvalue)"; 5935 break; 5936 5937 case SK_ConversionSequence: 5938 OS << "implicit conversion sequence ("; 5939 S->ICS->DebugPrint(); // FIXME: use OS 5940 OS << ")"; 5941 break; 5942 5943 case SK_ListInitialization: 5944 OS << "list aggregate initialization"; 5945 break; 5946 5947 case SK_ListConstructorCall: 5948 OS << "list initialization via constructor"; 5949 break; 5950 5951 case SK_UnwrapInitList: 5952 OS << "unwrap reference initializer list"; 5953 break; 5954 5955 case SK_RewrapInitList: 5956 OS << "rewrap reference initializer list"; 5957 break; 5958 5959 case SK_ConstructorInitialization: 5960 OS << "constructor initialization"; 5961 break; 5962 5963 case SK_ZeroInitialization: 5964 OS << "zero initialization"; 5965 break; 5966 5967 case SK_CAssignment: 5968 OS << "C assignment"; 5969 break; 5970 5971 case SK_StringInit: 5972 OS << "string initialization"; 5973 break; 5974 5975 case SK_ObjCObjectConversion: 5976 OS << "Objective-C object conversion"; 5977 break; 5978 5979 case SK_ArrayInit: 5980 OS << "array initialization"; 5981 break; 5982 5983 case SK_ParenthesizedArrayInit: 5984 OS << "parenthesized array initialization"; 5985 break; 5986 5987 case SK_PassByIndirectCopyRestore: 5988 OS << "pass by indirect copy and restore"; 5989 break; 5990 5991 case SK_PassByIndirectRestore: 5992 OS << "pass by indirect restore"; 5993 break; 5994 5995 case SK_ProduceObjCObject: 5996 OS << "Objective-C object retension"; 5997 break; 5998 5999 case SK_StdInitializerList: 6000 OS << "std::initializer_list from initializer list"; 6001 break; 6002 } 6003 } 6004 } 6005 6006 void InitializationSequence::dump() const { 6007 dump(llvm::errs()); 6008 } 6009 6010 static void DiagnoseNarrowingInInitList(Sema &S, InitializationSequence &Seq, 6011 QualType EntityType, 6012 const Expr *PreInit, 6013 const Expr *PostInit) { 6014 if (Seq.step_begin() == Seq.step_end() || PreInit->isValueDependent()) 6015 return; 6016 6017 // A narrowing conversion can only appear as the final implicit conversion in 6018 // an initialization sequence. 6019 const InitializationSequence::Step &LastStep = Seq.step_end()[-1]; 6020 if (LastStep.Kind != InitializationSequence::SK_ConversionSequence) 6021 return; 6022 6023 const ImplicitConversionSequence &ICS = *LastStep.ICS; 6024 const StandardConversionSequence *SCS = 0; 6025 switch (ICS.getKind()) { 6026 case ImplicitConversionSequence::StandardConversion: 6027 SCS = &ICS.Standard; 6028 break; 6029 case ImplicitConversionSequence::UserDefinedConversion: 6030 SCS = &ICS.UserDefined.After; 6031 break; 6032 case ImplicitConversionSequence::AmbiguousConversion: 6033 case ImplicitConversionSequence::EllipsisConversion: 6034 case ImplicitConversionSequence::BadConversion: 6035 return; 6036 } 6037 6038 // Determine the type prior to the narrowing conversion. If a conversion 6039 // operator was used, this may be different from both the type of the entity 6040 // and of the pre-initialization expression. 6041 QualType PreNarrowingType = PreInit->getType(); 6042 if (Seq.step_begin() + 1 != Seq.step_end()) 6043 PreNarrowingType = Seq.step_end()[-2].Type; 6044 6045 // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion. 6046 APValue ConstantValue; 6047 QualType ConstantType; 6048 switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue, 6049 ConstantType)) { 6050 case NK_Not_Narrowing: 6051 // No narrowing occurred. 6052 return; 6053 6054 case NK_Type_Narrowing: 6055 // This was a floating-to-integer conversion, which is always considered a 6056 // narrowing conversion even if the value is a constant and can be 6057 // represented exactly as an integer. 6058 S.Diag(PostInit->getLocStart(), 6059 S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus0x? 6060 diag::warn_init_list_type_narrowing 6061 : S.isSFINAEContext()? 6062 diag::err_init_list_type_narrowing_sfinae 6063 : diag::err_init_list_type_narrowing) 6064 << PostInit->getSourceRange() 6065 << PreNarrowingType.getLocalUnqualifiedType() 6066 << EntityType.getLocalUnqualifiedType(); 6067 break; 6068 6069 case NK_Constant_Narrowing: 6070 // A constant value was narrowed. 6071 S.Diag(PostInit->getLocStart(), 6072 S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus0x? 6073 diag::warn_init_list_constant_narrowing 6074 : S.isSFINAEContext()? 6075 diag::err_init_list_constant_narrowing_sfinae 6076 : diag::err_init_list_constant_narrowing) 6077 << PostInit->getSourceRange() 6078 << ConstantValue.getAsString(S.getASTContext(), ConstantType) 6079 << EntityType.getLocalUnqualifiedType(); 6080 break; 6081 6082 case NK_Variable_Narrowing: 6083 // A variable's value may have been narrowed. 6084 S.Diag(PostInit->getLocStart(), 6085 S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus0x? 6086 diag::warn_init_list_variable_narrowing 6087 : S.isSFINAEContext()? 6088 diag::err_init_list_variable_narrowing_sfinae 6089 : diag::err_init_list_variable_narrowing) 6090 << PostInit->getSourceRange() 6091 << PreNarrowingType.getLocalUnqualifiedType() 6092 << EntityType.getLocalUnqualifiedType(); 6093 break; 6094 } 6095 6096 SmallString<128> StaticCast; 6097 llvm::raw_svector_ostream OS(StaticCast); 6098 OS << "static_cast<"; 6099 if (const TypedefType *TT = EntityType->getAs<TypedefType>()) { 6100 // It's important to use the typedef's name if there is one so that the 6101 // fixit doesn't break code using types like int64_t. 6102 // 6103 // FIXME: This will break if the typedef requires qualification. But 6104 // getQualifiedNameAsString() includes non-machine-parsable components. 6105 OS << *TT->getDecl(); 6106 } else if (const BuiltinType *BT = EntityType->getAs<BuiltinType>()) 6107 OS << BT->getName(S.getLangOpts()); 6108 else { 6109 // Oops, we didn't find the actual type of the variable. Don't emit a fixit 6110 // with a broken cast. 6111 return; 6112 } 6113 OS << ">("; 6114 S.Diag(PostInit->getLocStart(), diag::note_init_list_narrowing_override) 6115 << PostInit->getSourceRange() 6116 << FixItHint::CreateInsertion(PostInit->getLocStart(), OS.str()) 6117 << FixItHint::CreateInsertion( 6118 S.getPreprocessor().getLocForEndOfToken(PostInit->getLocEnd()), ")"); 6119 } 6120 6121 //===----------------------------------------------------------------------===// 6122 // Initialization helper functions 6123 //===----------------------------------------------------------------------===// 6124 bool 6125 Sema::CanPerformCopyInitialization(const InitializedEntity &Entity, 6126 ExprResult Init) { 6127 if (Init.isInvalid()) 6128 return false; 6129 6130 Expr *InitE = Init.get(); 6131 assert(InitE && "No initialization expression"); 6132 6133 InitializationKind Kind = InitializationKind::CreateCopy(SourceLocation(), 6134 SourceLocation()); 6135 InitializationSequence Seq(*this, Entity, Kind, &InitE, 1); 6136 return !Seq.Failed(); 6137 } 6138 6139 ExprResult 6140 Sema::PerformCopyInitialization(const InitializedEntity &Entity, 6141 SourceLocation EqualLoc, 6142 ExprResult Init, 6143 bool TopLevelOfInitList, 6144 bool AllowExplicit) { 6145 if (Init.isInvalid()) 6146 return ExprError(); 6147 6148 Expr *InitE = Init.get(); 6149 assert(InitE && "No initialization expression?"); 6150 6151 if (EqualLoc.isInvalid()) 6152 EqualLoc = InitE->getLocStart(); 6153 6154 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(), 6155 EqualLoc, 6156 AllowExplicit); 6157 InitializationSequence Seq(*this, Entity, Kind, &InitE, 1); 6158 Init.release(); 6159 6160 ExprResult Result = Seq.Perform(*this, Entity, Kind, MultiExprArg(&InitE, 1)); 6161 6162 if (!Result.isInvalid() && TopLevelOfInitList) 6163 DiagnoseNarrowingInInitList(*this, Seq, Entity.getType(), 6164 InitE, Result.get()); 6165 6166 return Result; 6167 } 6168
