SemaInit.cpp revision 14a9d2c47ae6f6686ff264f235ac43fdba856d6e
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. The main entry 11// point is Sema::CheckInitList(), but all of the work is performed 12// within the InitListChecker class. 13// 14// This file also implements Sema::CheckInitializerTypes. 15// 16//===----------------------------------------------------------------------===// 17 18#include "SemaInit.h" 19#include "Lookup.h" 20#include "Sema.h" 21#include "clang/Lex/Preprocessor.h" 22#include "clang/Parse/Designator.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/ExprObjC.h" 26#include "clang/AST/TypeLoc.h" 27#include "llvm/Support/ErrorHandling.h" 28#include <map> 29using namespace clang; 30 31//===----------------------------------------------------------------------===// 32// Sema Initialization Checking 33//===----------------------------------------------------------------------===// 34 35static Expr *IsStringInit(Expr *Init, QualType DeclType, ASTContext &Context) { 36 const ArrayType *AT = Context.getAsArrayType(DeclType); 37 if (!AT) return 0; 38 39 if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT)) 40 return 0; 41 42 // See if this is a string literal or @encode. 43 Init = Init->IgnoreParens(); 44 45 // Handle @encode, which is a narrow string. 46 if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType()) 47 return Init; 48 49 // Otherwise we can only handle string literals. 50 StringLiteral *SL = dyn_cast<StringLiteral>(Init); 51 if (SL == 0) return 0; 52 53 QualType ElemTy = Context.getCanonicalType(AT->getElementType()); 54 // char array can be initialized with a narrow string. 55 // Only allow char x[] = "foo"; not char x[] = L"foo"; 56 if (!SL->isWide()) 57 return ElemTy->isCharType() ? Init : 0; 58 59 // wchar_t array can be initialized with a wide string: C99 6.7.8p15 (with 60 // correction from DR343): "An array with element type compatible with a 61 // qualified or unqualified version of wchar_t may be initialized by a wide 62 // string literal, optionally enclosed in braces." 63 if (Context.typesAreCompatible(Context.getWCharType(), 64 ElemTy.getUnqualifiedType())) 65 return Init; 66 67 return 0; 68} 69 70static void CheckStringInit(Expr *Str, QualType &DeclT, Sema &S) { 71 // Get the length of the string as parsed. 72 uint64_t StrLength = 73 cast<ConstantArrayType>(Str->getType())->getSize().getZExtValue(); 74 75 76 const ArrayType *AT = S.Context.getAsArrayType(DeclT); 77 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 78 // C99 6.7.8p14. We have an array of character type with unknown size 79 // being initialized to a string literal. 80 llvm::APSInt ConstVal(32); 81 ConstVal = StrLength; 82 // Return a new array type (C99 6.7.8p22). 83 DeclT = S.Context.getConstantArrayType(IAT->getElementType(), 84 ConstVal, 85 ArrayType::Normal, 0); 86 return; 87 } 88 89 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 90 91 // C99 6.7.8p14. We have an array of character type with known size. However, 92 // the size may be smaller or larger than the string we are initializing. 93 // FIXME: Avoid truncation for 64-bit length strings. 94 if (StrLength-1 > CAT->getSize().getZExtValue()) 95 S.Diag(Str->getSourceRange().getBegin(), 96 diag::warn_initializer_string_for_char_array_too_long) 97 << Str->getSourceRange(); 98 99 // Set the type to the actual size that we are initializing. If we have 100 // something like: 101 // char x[1] = "foo"; 102 // then this will set the string literal's type to char[1]. 103 Str->setType(DeclT); 104} 105 106//===----------------------------------------------------------------------===// 107// Semantic checking for initializer lists. 108//===----------------------------------------------------------------------===// 109 110/// @brief Semantic checking for initializer lists. 111/// 112/// The InitListChecker class contains a set of routines that each 113/// handle the initialization of a certain kind of entity, e.g., 114/// arrays, vectors, struct/union types, scalars, etc. The 115/// InitListChecker itself performs a recursive walk of the subobject 116/// structure of the type to be initialized, while stepping through 117/// the initializer list one element at a time. The IList and Index 118/// parameters to each of the Check* routines contain the active 119/// (syntactic) initializer list and the index into that initializer 120/// list that represents the current initializer. Each routine is 121/// responsible for moving that Index forward as it consumes elements. 122/// 123/// Each Check* routine also has a StructuredList/StructuredIndex 124/// arguments, which contains the current the "structured" (semantic) 125/// initializer list and the index into that initializer list where we 126/// are copying initializers as we map them over to the semantic 127/// list. Once we have completed our recursive walk of the subobject 128/// structure, we will have constructed a full semantic initializer 129/// list. 130/// 131/// C99 designators cause changes in the initializer list traversal, 132/// because they make the initialization "jump" into a specific 133/// subobject and then continue the initialization from that 134/// point. CheckDesignatedInitializer() recursively steps into the 135/// designated subobject and manages backing out the recursion to 136/// initialize the subobjects after the one designated. 137namespace { 138class InitListChecker { 139 Sema &SemaRef; 140 bool hadError; 141 std::map<InitListExpr *, InitListExpr *> SyntacticToSemantic; 142 InitListExpr *FullyStructuredList; 143 144 void CheckImplicitInitList(const InitializedEntity &Entity, 145 InitListExpr *ParentIList, QualType T, 146 unsigned &Index, InitListExpr *StructuredList, 147 unsigned &StructuredIndex, 148 bool TopLevelObject = false); 149 void CheckExplicitInitList(const InitializedEntity &Entity, 150 InitListExpr *IList, QualType &T, 151 unsigned &Index, InitListExpr *StructuredList, 152 unsigned &StructuredIndex, 153 bool TopLevelObject = false); 154 void CheckListElementTypes(const InitializedEntity &Entity, 155 InitListExpr *IList, QualType &DeclType, 156 bool SubobjectIsDesignatorContext, 157 unsigned &Index, 158 InitListExpr *StructuredList, 159 unsigned &StructuredIndex, 160 bool TopLevelObject = false); 161 void CheckSubElementType(const InitializedEntity &Entity, 162 InitListExpr *IList, QualType ElemType, 163 unsigned &Index, 164 InitListExpr *StructuredList, 165 unsigned &StructuredIndex); 166 void CheckScalarType(const InitializedEntity &Entity, 167 InitListExpr *IList, QualType DeclType, 168 unsigned &Index, 169 InitListExpr *StructuredList, 170 unsigned &StructuredIndex); 171 void CheckReferenceType(const InitializedEntity &Entity, 172 InitListExpr *IList, QualType DeclType, 173 unsigned &Index, 174 InitListExpr *StructuredList, 175 unsigned &StructuredIndex); 176 void CheckVectorType(const InitializedEntity &Entity, 177 InitListExpr *IList, QualType DeclType, unsigned &Index, 178 InitListExpr *StructuredList, 179 unsigned &StructuredIndex); 180 void CheckStructUnionTypes(const InitializedEntity &Entity, 181 InitListExpr *IList, QualType DeclType, 182 RecordDecl::field_iterator Field, 183 bool SubobjectIsDesignatorContext, unsigned &Index, 184 InitListExpr *StructuredList, 185 unsigned &StructuredIndex, 186 bool TopLevelObject = false); 187 void CheckArrayType(const InitializedEntity &Entity, 188 InitListExpr *IList, QualType &DeclType, 189 llvm::APSInt elementIndex, 190 bool SubobjectIsDesignatorContext, unsigned &Index, 191 InitListExpr *StructuredList, 192 unsigned &StructuredIndex); 193 bool CheckDesignatedInitializer(const InitializedEntity &Entity, 194 InitListExpr *IList, DesignatedInitExpr *DIE, 195 unsigned DesigIdx, 196 QualType &CurrentObjectType, 197 RecordDecl::field_iterator *NextField, 198 llvm::APSInt *NextElementIndex, 199 unsigned &Index, 200 InitListExpr *StructuredList, 201 unsigned &StructuredIndex, 202 bool FinishSubobjectInit, 203 bool TopLevelObject); 204 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 205 QualType CurrentObjectType, 206 InitListExpr *StructuredList, 207 unsigned StructuredIndex, 208 SourceRange InitRange); 209 void UpdateStructuredListElement(InitListExpr *StructuredList, 210 unsigned &StructuredIndex, 211 Expr *expr); 212 int numArrayElements(QualType DeclType); 213 int numStructUnionElements(QualType DeclType); 214 215 void FillInValueInitForField(unsigned Init, FieldDecl *Field, 216 const InitializedEntity &ParentEntity, 217 InitListExpr *ILE, bool &RequiresSecondPass); 218 void FillInValueInitializations(const InitializedEntity &Entity, 219 InitListExpr *ILE, bool &RequiresSecondPass); 220public: 221 InitListChecker(Sema &S, const InitializedEntity &Entity, 222 InitListExpr *IL, QualType &T); 223 bool HadError() { return hadError; } 224 225 // @brief Retrieves the fully-structured initializer list used for 226 // semantic analysis and code generation. 227 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; } 228}; 229} // end anonymous namespace 230 231void InitListChecker::FillInValueInitForField(unsigned Init, FieldDecl *Field, 232 const InitializedEntity &ParentEntity, 233 InitListExpr *ILE, 234 bool &RequiresSecondPass) { 235 SourceLocation Loc = ILE->getSourceRange().getBegin(); 236 unsigned NumInits = ILE->getNumInits(); 237 InitializedEntity MemberEntity 238 = InitializedEntity::InitializeMember(Field, &ParentEntity); 239 if (Init >= NumInits || !ILE->getInit(Init)) { 240 // FIXME: We probably don't need to handle references 241 // specially here, since value-initialization of references is 242 // handled in InitializationSequence. 243 if (Field->getType()->isReferenceType()) { 244 // C++ [dcl.init.aggr]p9: 245 // If an incomplete or empty initializer-list leaves a 246 // member of reference type uninitialized, the program is 247 // ill-formed. 248 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized) 249 << Field->getType() 250 << ILE->getSyntacticForm()->getSourceRange(); 251 SemaRef.Diag(Field->getLocation(), 252 diag::note_uninit_reference_member); 253 hadError = true; 254 return; 255 } 256 257 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 258 true); 259 InitializationSequence InitSeq(SemaRef, MemberEntity, Kind, 0, 0); 260 if (!InitSeq) { 261 InitSeq.Diagnose(SemaRef, MemberEntity, Kind, 0, 0); 262 hadError = true; 263 return; 264 } 265 266 Sema::OwningExprResult MemberInit 267 = InitSeq.Perform(SemaRef, MemberEntity, Kind, 268 Sema::MultiExprArg(SemaRef, 0, 0)); 269 if (MemberInit.isInvalid()) { 270 hadError = true; 271 return; 272 } 273 274 if (hadError) { 275 // Do nothing 276 } else if (Init < NumInits) { 277 ILE->setInit(Init, MemberInit.takeAs<Expr>()); 278 } else if (InitSeq.getKind() 279 == InitializationSequence::ConstructorInitialization) { 280 // Value-initialization requires a constructor call, so 281 // extend the initializer list to include the constructor 282 // call and make a note that we'll need to take another pass 283 // through the initializer list. 284 ILE->updateInit(SemaRef.Context, Init, MemberInit.takeAs<Expr>()); 285 RequiresSecondPass = true; 286 } 287 } else if (InitListExpr *InnerILE 288 = dyn_cast<InitListExpr>(ILE->getInit(Init))) 289 FillInValueInitializations(MemberEntity, InnerILE, 290 RequiresSecondPass); 291} 292 293/// Recursively replaces NULL values within the given initializer list 294/// with expressions that perform value-initialization of the 295/// appropriate type. 296void 297InitListChecker::FillInValueInitializations(const InitializedEntity &Entity, 298 InitListExpr *ILE, 299 bool &RequiresSecondPass) { 300 assert((ILE->getType() != SemaRef.Context.VoidTy) && 301 "Should not have void type"); 302 SourceLocation Loc = ILE->getSourceRange().getBegin(); 303 if (ILE->getSyntacticForm()) 304 Loc = ILE->getSyntacticForm()->getSourceRange().getBegin(); 305 306 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) { 307 if (RType->getDecl()->isUnion() && 308 ILE->getInitializedFieldInUnion()) 309 FillInValueInitForField(0, ILE->getInitializedFieldInUnion(), 310 Entity, ILE, RequiresSecondPass); 311 else { 312 unsigned Init = 0; 313 for (RecordDecl::field_iterator 314 Field = RType->getDecl()->field_begin(), 315 FieldEnd = RType->getDecl()->field_end(); 316 Field != FieldEnd; ++Field) { 317 if (Field->isUnnamedBitfield()) 318 continue; 319 320 if (hadError) 321 return; 322 323 FillInValueInitForField(Init, *Field, Entity, ILE, RequiresSecondPass); 324 if (hadError) 325 return; 326 327 ++Init; 328 329 // Only look at the first initialization of a union. 330 if (RType->getDecl()->isUnion()) 331 break; 332 } 333 } 334 335 return; 336 } 337 338 QualType ElementType; 339 340 InitializedEntity ElementEntity = Entity; 341 unsigned NumInits = ILE->getNumInits(); 342 unsigned NumElements = NumInits; 343 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) { 344 ElementType = AType->getElementType(); 345 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) 346 NumElements = CAType->getSize().getZExtValue(); 347 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, 348 0, Entity); 349 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) { 350 ElementType = VType->getElementType(); 351 NumElements = VType->getNumElements(); 352 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, 353 0, Entity); 354 } else 355 ElementType = ILE->getType(); 356 357 358 for (unsigned Init = 0; Init != NumElements; ++Init) { 359 if (hadError) 360 return; 361 362 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement || 363 ElementEntity.getKind() == InitializedEntity::EK_VectorElement) 364 ElementEntity.setElementIndex(Init); 365 366 if (Init >= NumInits || !ILE->getInit(Init)) { 367 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 368 true); 369 InitializationSequence InitSeq(SemaRef, ElementEntity, Kind, 0, 0); 370 if (!InitSeq) { 371 InitSeq.Diagnose(SemaRef, ElementEntity, Kind, 0, 0); 372 hadError = true; 373 return; 374 } 375 376 Sema::OwningExprResult ElementInit 377 = InitSeq.Perform(SemaRef, ElementEntity, Kind, 378 Sema::MultiExprArg(SemaRef, 0, 0)); 379 if (ElementInit.isInvalid()) { 380 hadError = true; 381 return; 382 } 383 384 if (hadError) { 385 // Do nothing 386 } else if (Init < NumInits) { 387 ILE->setInit(Init, ElementInit.takeAs<Expr>()); 388 } else if (InitSeq.getKind() 389 == InitializationSequence::ConstructorInitialization) { 390 // Value-initialization requires a constructor call, so 391 // extend the initializer list to include the constructor 392 // call and make a note that we'll need to take another pass 393 // through the initializer list. 394 ILE->updateInit(SemaRef.Context, Init, ElementInit.takeAs<Expr>()); 395 RequiresSecondPass = true; 396 } 397 } else if (InitListExpr *InnerILE 398 = dyn_cast<InitListExpr>(ILE->getInit(Init))) 399 FillInValueInitializations(ElementEntity, InnerILE, RequiresSecondPass); 400 } 401} 402 403 404InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity, 405 InitListExpr *IL, QualType &T) 406 : SemaRef(S) { 407 hadError = false; 408 409 unsigned newIndex = 0; 410 unsigned newStructuredIndex = 0; 411 FullyStructuredList 412 = getStructuredSubobjectInit(IL, newIndex, T, 0, 0, IL->getSourceRange()); 413 CheckExplicitInitList(Entity, IL, T, newIndex, 414 FullyStructuredList, newStructuredIndex, 415 /*TopLevelObject=*/true); 416 417 if (!hadError) { 418 bool RequiresSecondPass = false; 419 FillInValueInitializations(Entity, FullyStructuredList, RequiresSecondPass); 420 if (RequiresSecondPass && !hadError) 421 FillInValueInitializations(Entity, FullyStructuredList, 422 RequiresSecondPass); 423 } 424} 425 426int InitListChecker::numArrayElements(QualType DeclType) { 427 // FIXME: use a proper constant 428 int maxElements = 0x7FFFFFFF; 429 if (const ConstantArrayType *CAT = 430 SemaRef.Context.getAsConstantArrayType(DeclType)) { 431 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 432 } 433 return maxElements; 434} 435 436int InitListChecker::numStructUnionElements(QualType DeclType) { 437 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl(); 438 int InitializableMembers = 0; 439 for (RecordDecl::field_iterator 440 Field = structDecl->field_begin(), 441 FieldEnd = structDecl->field_end(); 442 Field != FieldEnd; ++Field) { 443 if ((*Field)->getIdentifier() || !(*Field)->isBitField()) 444 ++InitializableMembers; 445 } 446 if (structDecl->isUnion()) 447 return std::min(InitializableMembers, 1); 448 return InitializableMembers - structDecl->hasFlexibleArrayMember(); 449} 450 451void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity, 452 InitListExpr *ParentIList, 453 QualType T, unsigned &Index, 454 InitListExpr *StructuredList, 455 unsigned &StructuredIndex, 456 bool TopLevelObject) { 457 int maxElements = 0; 458 459 if (T->isArrayType()) 460 maxElements = numArrayElements(T); 461 else if (T->isRecordType()) 462 maxElements = numStructUnionElements(T); 463 else if (T->isVectorType()) 464 maxElements = T->getAs<VectorType>()->getNumElements(); 465 else 466 assert(0 && "CheckImplicitInitList(): Illegal type"); 467 468 if (maxElements == 0) { 469 SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(), 470 diag::err_implicit_empty_initializer); 471 ++Index; 472 hadError = true; 473 return; 474 } 475 476 // Build a structured initializer list corresponding to this subobject. 477 InitListExpr *StructuredSubobjectInitList 478 = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList, 479 StructuredIndex, 480 SourceRange(ParentIList->getInit(Index)->getSourceRange().getBegin(), 481 ParentIList->getSourceRange().getEnd())); 482 unsigned StructuredSubobjectInitIndex = 0; 483 484 // Check the element types and build the structural subobject. 485 unsigned StartIndex = Index; 486 CheckListElementTypes(Entity, ParentIList, T, 487 /*SubobjectIsDesignatorContext=*/false, Index, 488 StructuredSubobjectInitList, 489 StructuredSubobjectInitIndex, 490 TopLevelObject); 491 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1); 492 StructuredSubobjectInitList->setType(T); 493 494 // Update the structured sub-object initializer so that it's ending 495 // range corresponds with the end of the last initializer it used. 496 if (EndIndex < ParentIList->getNumInits()) { 497 SourceLocation EndLoc 498 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd(); 499 StructuredSubobjectInitList->setRBraceLoc(EndLoc); 500 } 501 502 // Warn about missing braces. 503 if (T->isArrayType() || T->isRecordType()) { 504 SemaRef.Diag(StructuredSubobjectInitList->getLocStart(), 505 diag::warn_missing_braces) 506 << StructuredSubobjectInitList->getSourceRange() 507 << FixItHint::CreateInsertion(StructuredSubobjectInitList->getLocStart(), 508 "{") 509 << FixItHint::CreateInsertion(SemaRef.PP.getLocForEndOfToken( 510 StructuredSubobjectInitList->getLocEnd()), 511 "}"); 512 } 513} 514 515void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity, 516 InitListExpr *IList, QualType &T, 517 unsigned &Index, 518 InitListExpr *StructuredList, 519 unsigned &StructuredIndex, 520 bool TopLevelObject) { 521 assert(IList->isExplicit() && "Illegal Implicit InitListExpr"); 522 SyntacticToSemantic[IList] = StructuredList; 523 StructuredList->setSyntacticForm(IList); 524 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true, 525 Index, StructuredList, StructuredIndex, TopLevelObject); 526 IList->setType(T.getNonReferenceType()); 527 StructuredList->setType(T.getNonReferenceType()); 528 if (hadError) 529 return; 530 531 if (Index < IList->getNumInits()) { 532 // We have leftover initializers 533 if (StructuredIndex == 1 && 534 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context)) { 535 unsigned DK = diag::warn_excess_initializers_in_char_array_initializer; 536 if (SemaRef.getLangOptions().CPlusPlus) { 537 DK = diag::err_excess_initializers_in_char_array_initializer; 538 hadError = true; 539 } 540 // Special-case 541 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) 542 << IList->getInit(Index)->getSourceRange(); 543 } else if (!T->isIncompleteType()) { 544 // Don't complain for incomplete types, since we'll get an error 545 // elsewhere 546 QualType CurrentObjectType = StructuredList->getType(); 547 int initKind = 548 CurrentObjectType->isArrayType()? 0 : 549 CurrentObjectType->isVectorType()? 1 : 550 CurrentObjectType->isScalarType()? 2 : 551 CurrentObjectType->isUnionType()? 3 : 552 4; 553 554 unsigned DK = diag::warn_excess_initializers; 555 if (SemaRef.getLangOptions().CPlusPlus) { 556 DK = diag::err_excess_initializers; 557 hadError = true; 558 } 559 if (SemaRef.getLangOptions().OpenCL && initKind == 1) { 560 DK = diag::err_excess_initializers; 561 hadError = true; 562 } 563 564 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) 565 << initKind << IList->getInit(Index)->getSourceRange(); 566 } 567 } 568 569 if (T->isScalarType() && !TopLevelObject) 570 SemaRef.Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init) 571 << IList->getSourceRange() 572 << FixItHint::CreateRemoval(IList->getLocStart()) 573 << FixItHint::CreateRemoval(IList->getLocEnd()); 574} 575 576void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity, 577 InitListExpr *IList, 578 QualType &DeclType, 579 bool SubobjectIsDesignatorContext, 580 unsigned &Index, 581 InitListExpr *StructuredList, 582 unsigned &StructuredIndex, 583 bool TopLevelObject) { 584 if (DeclType->isScalarType()) { 585 CheckScalarType(Entity, IList, DeclType, Index, 586 StructuredList, StructuredIndex); 587 } else if (DeclType->isVectorType()) { 588 CheckVectorType(Entity, IList, DeclType, Index, 589 StructuredList, StructuredIndex); 590 } else if (DeclType->isAggregateType()) { 591 if (DeclType->isRecordType()) { 592 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 593 CheckStructUnionTypes(Entity, IList, DeclType, RD->field_begin(), 594 SubobjectIsDesignatorContext, Index, 595 StructuredList, StructuredIndex, 596 TopLevelObject); 597 } else if (DeclType->isArrayType()) { 598 llvm::APSInt Zero( 599 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()), 600 false); 601 CheckArrayType(Entity, IList, DeclType, Zero, 602 SubobjectIsDesignatorContext, Index, 603 StructuredList, StructuredIndex); 604 } else 605 assert(0 && "Aggregate that isn't a structure or array?!"); 606 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) { 607 // This type is invalid, issue a diagnostic. 608 ++Index; 609 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) 610 << DeclType; 611 hadError = true; 612 } else if (DeclType->isRecordType()) { 613 // C++ [dcl.init]p14: 614 // [...] If the class is an aggregate (8.5.1), and the initializer 615 // is a brace-enclosed list, see 8.5.1. 616 // 617 // Note: 8.5.1 is handled below; here, we diagnose the case where 618 // we have an initializer list and a destination type that is not 619 // an aggregate. 620 // FIXME: In C++0x, this is yet another form of initialization. 621 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) 622 << DeclType << IList->getSourceRange(); 623 hadError = true; 624 } else if (DeclType->isReferenceType()) { 625 CheckReferenceType(Entity, IList, DeclType, Index, 626 StructuredList, StructuredIndex); 627 } else if (DeclType->isObjCObjectType()) { 628 SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class) 629 << DeclType; 630 hadError = true; 631 } else { 632 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) 633 << DeclType; 634 hadError = true; 635 } 636} 637 638void InitListChecker::CheckSubElementType(const InitializedEntity &Entity, 639 InitListExpr *IList, 640 QualType ElemType, 641 unsigned &Index, 642 InitListExpr *StructuredList, 643 unsigned &StructuredIndex) { 644 Expr *expr = IList->getInit(Index); 645 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 646 unsigned newIndex = 0; 647 unsigned newStructuredIndex = 0; 648 InitListExpr *newStructuredList 649 = getStructuredSubobjectInit(IList, Index, ElemType, 650 StructuredList, StructuredIndex, 651 SubInitList->getSourceRange()); 652 CheckExplicitInitList(Entity, SubInitList, ElemType, newIndex, 653 newStructuredList, newStructuredIndex); 654 ++StructuredIndex; 655 ++Index; 656 } else if (Expr *Str = IsStringInit(expr, ElemType, SemaRef.Context)) { 657 CheckStringInit(Str, ElemType, SemaRef); 658 UpdateStructuredListElement(StructuredList, StructuredIndex, Str); 659 ++Index; 660 } else if (ElemType->isScalarType()) { 661 CheckScalarType(Entity, IList, ElemType, Index, 662 StructuredList, StructuredIndex); 663 } else if (ElemType->isReferenceType()) { 664 CheckReferenceType(Entity, IList, ElemType, Index, 665 StructuredList, StructuredIndex); 666 } else { 667 if (SemaRef.getLangOptions().CPlusPlus) { 668 // C++ [dcl.init.aggr]p12: 669 // All implicit type conversions (clause 4) are considered when 670 // initializing the aggregate member with an ini- tializer from 671 // an initializer-list. If the initializer can initialize a 672 // member, the member is initialized. [...] 673 674 // FIXME: Better EqualLoc? 675 InitializationKind Kind = 676 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation()); 677 InitializationSequence Seq(SemaRef, Entity, Kind, &expr, 1); 678 679 if (Seq) { 680 Sema::OwningExprResult Result = 681 Seq.Perform(SemaRef, Entity, Kind, 682 Sema::MultiExprArg(SemaRef, (void **)&expr, 1)); 683 if (Result.isInvalid()) 684 hadError = true; 685 686 UpdateStructuredListElement(StructuredList, StructuredIndex, 687 Result.takeAs<Expr>()); 688 ++Index; 689 return; 690 } 691 692 // Fall through for subaggregate initialization 693 } else { 694 // C99 6.7.8p13: 695 // 696 // The initializer for a structure or union object that has 697 // automatic storage duration shall be either an initializer 698 // list as described below, or a single expression that has 699 // compatible structure or union type. In the latter case, the 700 // initial value of the object, including unnamed members, is 701 // that of the expression. 702 if ((ElemType->isRecordType() || ElemType->isVectorType()) && 703 SemaRef.Context.hasSameUnqualifiedType(expr->getType(), ElemType)) { 704 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 705 ++Index; 706 return; 707 } 708 709 // Fall through for subaggregate initialization 710 } 711 712 // C++ [dcl.init.aggr]p12: 713 // 714 // [...] Otherwise, if the member is itself a non-empty 715 // subaggregate, brace elision is assumed and the initializer is 716 // considered for the initialization of the first member of 717 // the subaggregate. 718 if (ElemType->isAggregateType() || ElemType->isVectorType()) { 719 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList, 720 StructuredIndex); 721 ++StructuredIndex; 722 } else { 723 // We cannot initialize this element, so let 724 // PerformCopyInitialization produce the appropriate diagnostic. 725 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), 726 SemaRef.Owned(expr)); 727 IList->setInit(Index, 0); 728 hadError = true; 729 ++Index; 730 ++StructuredIndex; 731 } 732 } 733} 734 735void InitListChecker::CheckScalarType(const InitializedEntity &Entity, 736 InitListExpr *IList, QualType DeclType, 737 unsigned &Index, 738 InitListExpr *StructuredList, 739 unsigned &StructuredIndex) { 740 if (Index < IList->getNumInits()) { 741 Expr *expr = IList->getInit(Index); 742 if (isa<InitListExpr>(expr)) { 743 SemaRef.Diag(IList->getLocStart(), 744 diag::err_many_braces_around_scalar_init) 745 << IList->getSourceRange(); 746 hadError = true; 747 ++Index; 748 ++StructuredIndex; 749 return; 750 } else if (isa<DesignatedInitExpr>(expr)) { 751 SemaRef.Diag(expr->getSourceRange().getBegin(), 752 diag::err_designator_for_scalar_init) 753 << DeclType << expr->getSourceRange(); 754 hadError = true; 755 ++Index; 756 ++StructuredIndex; 757 return; 758 } 759 760 Sema::OwningExprResult Result = 761 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 762 SemaRef.Owned(expr)); 763 764 Expr *ResultExpr = 0; 765 766 if (Result.isInvalid()) 767 hadError = true; // types weren't compatible. 768 else { 769 ResultExpr = Result.takeAs<Expr>(); 770 771 if (ResultExpr != expr) { 772 // The type was promoted, update initializer list. 773 IList->setInit(Index, ResultExpr); 774 } 775 } 776 if (hadError) 777 ++StructuredIndex; 778 else 779 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr); 780 ++Index; 781 } else { 782 SemaRef.Diag(IList->getLocStart(), diag::err_empty_scalar_initializer) 783 << IList->getSourceRange(); 784 hadError = true; 785 ++Index; 786 ++StructuredIndex; 787 return; 788 } 789} 790 791void InitListChecker::CheckReferenceType(const InitializedEntity &Entity, 792 InitListExpr *IList, QualType DeclType, 793 unsigned &Index, 794 InitListExpr *StructuredList, 795 unsigned &StructuredIndex) { 796 if (Index < IList->getNumInits()) { 797 Expr *expr = IList->getInit(Index); 798 if (isa<InitListExpr>(expr)) { 799 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) 800 << DeclType << IList->getSourceRange(); 801 hadError = true; 802 ++Index; 803 ++StructuredIndex; 804 return; 805 } 806 807 Sema::OwningExprResult Result = 808 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 809 SemaRef.Owned(expr)); 810 811 if (Result.isInvalid()) 812 hadError = true; 813 814 expr = Result.takeAs<Expr>(); 815 IList->setInit(Index, expr); 816 817 if (hadError) 818 ++StructuredIndex; 819 else 820 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 821 ++Index; 822 } else { 823 // FIXME: It would be wonderful if we could point at the actual member. In 824 // general, it would be useful to pass location information down the stack, 825 // so that we know the location (or decl) of the "current object" being 826 // initialized. 827 SemaRef.Diag(IList->getLocStart(), 828 diag::err_init_reference_member_uninitialized) 829 << DeclType 830 << IList->getSourceRange(); 831 hadError = true; 832 ++Index; 833 ++StructuredIndex; 834 return; 835 } 836} 837 838void InitListChecker::CheckVectorType(const InitializedEntity &Entity, 839 InitListExpr *IList, QualType DeclType, 840 unsigned &Index, 841 InitListExpr *StructuredList, 842 unsigned &StructuredIndex) { 843 if (Index < IList->getNumInits()) { 844 const VectorType *VT = DeclType->getAs<VectorType>(); 845 unsigned maxElements = VT->getNumElements(); 846 unsigned numEltsInit = 0; 847 QualType elementType = VT->getElementType(); 848 849 if (!SemaRef.getLangOptions().OpenCL) { 850 InitializedEntity ElementEntity = 851 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 852 853 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) { 854 // Don't attempt to go past the end of the init list 855 if (Index >= IList->getNumInits()) 856 break; 857 858 ElementEntity.setElementIndex(Index); 859 CheckSubElementType(ElementEntity, IList, elementType, Index, 860 StructuredList, StructuredIndex); 861 } 862 } else { 863 InitializedEntity ElementEntity = 864 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 865 866 // OpenCL initializers allows vectors to be constructed from vectors. 867 for (unsigned i = 0; i < maxElements; ++i) { 868 // Don't attempt to go past the end of the init list 869 if (Index >= IList->getNumInits()) 870 break; 871 872 ElementEntity.setElementIndex(Index); 873 874 QualType IType = IList->getInit(Index)->getType(); 875 if (!IType->isVectorType()) { 876 CheckSubElementType(ElementEntity, IList, elementType, Index, 877 StructuredList, StructuredIndex); 878 ++numEltsInit; 879 } else { 880 const VectorType *IVT = IType->getAs<VectorType>(); 881 unsigned numIElts = IVT->getNumElements(); 882 QualType VecType = SemaRef.Context.getExtVectorType(elementType, 883 numIElts); 884 CheckSubElementType(ElementEntity, IList, VecType, Index, 885 StructuredList, StructuredIndex); 886 numEltsInit += numIElts; 887 } 888 } 889 } 890 891 // OpenCL requires all elements to be initialized. 892 if (numEltsInit != maxElements) 893 if (SemaRef.getLangOptions().OpenCL) 894 SemaRef.Diag(IList->getSourceRange().getBegin(), 895 diag::err_vector_incorrect_num_initializers) 896 << (numEltsInit < maxElements) << maxElements << numEltsInit; 897 } 898} 899 900void InitListChecker::CheckArrayType(const InitializedEntity &Entity, 901 InitListExpr *IList, QualType &DeclType, 902 llvm::APSInt elementIndex, 903 bool SubobjectIsDesignatorContext, 904 unsigned &Index, 905 InitListExpr *StructuredList, 906 unsigned &StructuredIndex) { 907 // Check for the special-case of initializing an array with a string. 908 if (Index < IList->getNumInits()) { 909 if (Expr *Str = IsStringInit(IList->getInit(Index), DeclType, 910 SemaRef.Context)) { 911 CheckStringInit(Str, DeclType, SemaRef); 912 // We place the string literal directly into the resulting 913 // initializer list. This is the only place where the structure 914 // of the structured initializer list doesn't match exactly, 915 // because doing so would involve allocating one character 916 // constant for each string. 917 UpdateStructuredListElement(StructuredList, StructuredIndex, Str); 918 StructuredList->resizeInits(SemaRef.Context, StructuredIndex); 919 ++Index; 920 return; 921 } 922 } 923 if (const VariableArrayType *VAT = 924 SemaRef.Context.getAsVariableArrayType(DeclType)) { 925 // Check for VLAs; in standard C it would be possible to check this 926 // earlier, but I don't know where clang accepts VLAs (gcc accepts 927 // them in all sorts of strange places). 928 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(), 929 diag::err_variable_object_no_init) 930 << VAT->getSizeExpr()->getSourceRange(); 931 hadError = true; 932 ++Index; 933 ++StructuredIndex; 934 return; 935 } 936 937 // We might know the maximum number of elements in advance. 938 llvm::APSInt maxElements(elementIndex.getBitWidth(), 939 elementIndex.isUnsigned()); 940 bool maxElementsKnown = false; 941 if (const ConstantArrayType *CAT = 942 SemaRef.Context.getAsConstantArrayType(DeclType)) { 943 maxElements = CAT->getSize(); 944 elementIndex.extOrTrunc(maxElements.getBitWidth()); 945 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 946 maxElementsKnown = true; 947 } 948 949 QualType elementType = SemaRef.Context.getAsArrayType(DeclType) 950 ->getElementType(); 951 while (Index < IList->getNumInits()) { 952 Expr *Init = IList->getInit(Index); 953 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 954 // If we're not the subobject that matches up with the '{' for 955 // the designator, we shouldn't be handling the 956 // designator. Return immediately. 957 if (!SubobjectIsDesignatorContext) 958 return; 959 960 // Handle this designated initializer. elementIndex will be 961 // updated to be the next array element we'll initialize. 962 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 963 DeclType, 0, &elementIndex, Index, 964 StructuredList, StructuredIndex, true, 965 false)) { 966 hadError = true; 967 continue; 968 } 969 970 if (elementIndex.getBitWidth() > maxElements.getBitWidth()) 971 maxElements.extend(elementIndex.getBitWidth()); 972 else if (elementIndex.getBitWidth() < maxElements.getBitWidth()) 973 elementIndex.extend(maxElements.getBitWidth()); 974 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 975 976 // If the array is of incomplete type, keep track of the number of 977 // elements in the initializer. 978 if (!maxElementsKnown && elementIndex > maxElements) 979 maxElements = elementIndex; 980 981 continue; 982 } 983 984 // If we know the maximum number of elements, and we've already 985 // hit it, stop consuming elements in the initializer list. 986 if (maxElementsKnown && elementIndex == maxElements) 987 break; 988 989 InitializedEntity ElementEntity = 990 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex, 991 Entity); 992 // Check this element. 993 CheckSubElementType(ElementEntity, IList, elementType, Index, 994 StructuredList, StructuredIndex); 995 ++elementIndex; 996 997 // If the array is of incomplete type, keep track of the number of 998 // elements in the initializer. 999 if (!maxElementsKnown && elementIndex > maxElements) 1000 maxElements = elementIndex; 1001 } 1002 if (!hadError && DeclType->isIncompleteArrayType()) { 1003 // If this is an incomplete array type, the actual type needs to 1004 // be calculated here. 1005 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned()); 1006 if (maxElements == Zero) { 1007 // Sizing an array implicitly to zero is not allowed by ISO C, 1008 // but is supported by GNU. 1009 SemaRef.Diag(IList->getLocStart(), 1010 diag::ext_typecheck_zero_array_size); 1011 } 1012 1013 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements, 1014 ArrayType::Normal, 0); 1015 } 1016} 1017 1018void InitListChecker::CheckStructUnionTypes(const InitializedEntity &Entity, 1019 InitListExpr *IList, 1020 QualType DeclType, 1021 RecordDecl::field_iterator Field, 1022 bool SubobjectIsDesignatorContext, 1023 unsigned &Index, 1024 InitListExpr *StructuredList, 1025 unsigned &StructuredIndex, 1026 bool TopLevelObject) { 1027 RecordDecl* structDecl = DeclType->getAs<RecordType>()->getDecl(); 1028 1029 // If the record is invalid, some of it's members are invalid. To avoid 1030 // confusion, we forgo checking the intializer for the entire record. 1031 if (structDecl->isInvalidDecl()) { 1032 hadError = true; 1033 return; 1034 } 1035 1036 if (DeclType->isUnionType() && IList->getNumInits() == 0) { 1037 // Value-initialize the first named member of the union. 1038 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1039 for (RecordDecl::field_iterator FieldEnd = RD->field_end(); 1040 Field != FieldEnd; ++Field) { 1041 if (Field->getDeclName()) { 1042 StructuredList->setInitializedFieldInUnion(*Field); 1043 break; 1044 } 1045 } 1046 return; 1047 } 1048 1049 // If structDecl is a forward declaration, this loop won't do 1050 // anything except look at designated initializers; That's okay, 1051 // because an error should get printed out elsewhere. It might be 1052 // worthwhile to skip over the rest of the initializer, though. 1053 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1054 RecordDecl::field_iterator FieldEnd = RD->field_end(); 1055 bool InitializedSomething = false; 1056 bool CheckForMissingFields = true; 1057 while (Index < IList->getNumInits()) { 1058 Expr *Init = IList->getInit(Index); 1059 1060 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 1061 // If we're not the subobject that matches up with the '{' for 1062 // the designator, we shouldn't be handling the 1063 // designator. Return immediately. 1064 if (!SubobjectIsDesignatorContext) 1065 return; 1066 1067 // Handle this designated initializer. Field will be updated to 1068 // the next field that we'll be initializing. 1069 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 1070 DeclType, &Field, 0, Index, 1071 StructuredList, StructuredIndex, 1072 true, TopLevelObject)) 1073 hadError = true; 1074 1075 InitializedSomething = true; 1076 1077 // Disable check for missing fields when designators are used. 1078 // This matches gcc behaviour. 1079 CheckForMissingFields = false; 1080 continue; 1081 } 1082 1083 if (Field == FieldEnd) { 1084 // We've run out of fields. We're done. 1085 break; 1086 } 1087 1088 // We've already initialized a member of a union. We're done. 1089 if (InitializedSomething && DeclType->isUnionType()) 1090 break; 1091 1092 // If we've hit the flexible array member at the end, we're done. 1093 if (Field->getType()->isIncompleteArrayType()) 1094 break; 1095 1096 if (Field->isUnnamedBitfield()) { 1097 // Don't initialize unnamed bitfields, e.g. "int : 20;" 1098 ++Field; 1099 continue; 1100 } 1101 1102 InitializedEntity MemberEntity = 1103 InitializedEntity::InitializeMember(*Field, &Entity); 1104 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1105 StructuredList, StructuredIndex); 1106 InitializedSomething = true; 1107 1108 if (DeclType->isUnionType()) { 1109 // Initialize the first field within the union. 1110 StructuredList->setInitializedFieldInUnion(*Field); 1111 } 1112 1113 ++Field; 1114 } 1115 1116 // Emit warnings for missing struct field initializers. 1117 if (InitializedSomething && CheckForMissingFields && Field != FieldEnd && 1118 !Field->getType()->isIncompleteArrayType() && !DeclType->isUnionType()) { 1119 // It is possible we have one or more unnamed bitfields remaining. 1120 // Find first (if any) named field and emit warning. 1121 for (RecordDecl::field_iterator it = Field, end = RD->field_end(); 1122 it != end; ++it) { 1123 if (!it->isUnnamedBitfield()) { 1124 SemaRef.Diag(IList->getSourceRange().getEnd(), 1125 diag::warn_missing_field_initializers) << it->getName(); 1126 break; 1127 } 1128 } 1129 } 1130 1131 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() || 1132 Index >= IList->getNumInits()) 1133 return; 1134 1135 // Handle GNU flexible array initializers. 1136 if (!TopLevelObject && 1137 (!isa<InitListExpr>(IList->getInit(Index)) || 1138 cast<InitListExpr>(IList->getInit(Index))->getNumInits() > 0)) { 1139 SemaRef.Diag(IList->getInit(Index)->getSourceRange().getBegin(), 1140 diag::err_flexible_array_init_nonempty) 1141 << IList->getInit(Index)->getSourceRange().getBegin(); 1142 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1143 << *Field; 1144 hadError = true; 1145 ++Index; 1146 return; 1147 } else { 1148 SemaRef.Diag(IList->getInit(Index)->getSourceRange().getBegin(), 1149 diag::ext_flexible_array_init) 1150 << IList->getInit(Index)->getSourceRange().getBegin(); 1151 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1152 << *Field; 1153 } 1154 1155 InitializedEntity MemberEntity = 1156 InitializedEntity::InitializeMember(*Field, &Entity); 1157 1158 if (isa<InitListExpr>(IList->getInit(Index))) 1159 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1160 StructuredList, StructuredIndex); 1161 else 1162 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index, 1163 StructuredList, StructuredIndex); 1164} 1165 1166/// \brief Expand a field designator that refers to a member of an 1167/// anonymous struct or union into a series of field designators that 1168/// refers to the field within the appropriate subobject. 1169/// 1170/// Field/FieldIndex will be updated to point to the (new) 1171/// currently-designated field. 1172static void ExpandAnonymousFieldDesignator(Sema &SemaRef, 1173 DesignatedInitExpr *DIE, 1174 unsigned DesigIdx, 1175 FieldDecl *Field, 1176 RecordDecl::field_iterator &FieldIter, 1177 unsigned &FieldIndex) { 1178 typedef DesignatedInitExpr::Designator Designator; 1179 1180 // Build the path from the current object to the member of the 1181 // anonymous struct/union (backwards). 1182 llvm::SmallVector<FieldDecl *, 4> Path; 1183 SemaRef.BuildAnonymousStructUnionMemberPath(Field, Path); 1184 1185 // Build the replacement designators. 1186 llvm::SmallVector<Designator, 4> Replacements; 1187 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 1188 FI = Path.rbegin(), FIEnd = Path.rend(); 1189 FI != FIEnd; ++FI) { 1190 if (FI + 1 == FIEnd) 1191 Replacements.push_back(Designator((IdentifierInfo *)0, 1192 DIE->getDesignator(DesigIdx)->getDotLoc(), 1193 DIE->getDesignator(DesigIdx)->getFieldLoc())); 1194 else 1195 Replacements.push_back(Designator((IdentifierInfo *)0, SourceLocation(), 1196 SourceLocation())); 1197 Replacements.back().setField(*FI); 1198 } 1199 1200 // Expand the current designator into the set of replacement 1201 // designators, so we have a full subobject path down to where the 1202 // member of the anonymous struct/union is actually stored. 1203 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0], 1204 &Replacements[0] + Replacements.size()); 1205 1206 // Update FieldIter/FieldIndex; 1207 RecordDecl *Record = cast<RecordDecl>(Path.back()->getDeclContext()); 1208 FieldIter = Record->field_begin(); 1209 FieldIndex = 0; 1210 for (RecordDecl::field_iterator FEnd = Record->field_end(); 1211 FieldIter != FEnd; ++FieldIter) { 1212 if (FieldIter->isUnnamedBitfield()) 1213 continue; 1214 1215 if (*FieldIter == Path.back()) 1216 return; 1217 1218 ++FieldIndex; 1219 } 1220 1221 assert(false && "Unable to find anonymous struct/union field"); 1222} 1223 1224/// @brief Check the well-formedness of a C99 designated initializer. 1225/// 1226/// Determines whether the designated initializer @p DIE, which 1227/// resides at the given @p Index within the initializer list @p 1228/// IList, is well-formed for a current object of type @p DeclType 1229/// (C99 6.7.8). The actual subobject that this designator refers to 1230/// within the current subobject is returned in either 1231/// @p NextField or @p NextElementIndex (whichever is appropriate). 1232/// 1233/// @param IList The initializer list in which this designated 1234/// initializer occurs. 1235/// 1236/// @param DIE The designated initializer expression. 1237/// 1238/// @param DesigIdx The index of the current designator. 1239/// 1240/// @param DeclType The type of the "current object" (C99 6.7.8p17), 1241/// into which the designation in @p DIE should refer. 1242/// 1243/// @param NextField If non-NULL and the first designator in @p DIE is 1244/// a field, this will be set to the field declaration corresponding 1245/// to the field named by the designator. 1246/// 1247/// @param NextElementIndex If non-NULL and the first designator in @p 1248/// DIE is an array designator or GNU array-range designator, this 1249/// will be set to the last index initialized by this designator. 1250/// 1251/// @param Index Index into @p IList where the designated initializer 1252/// @p DIE occurs. 1253/// 1254/// @param StructuredList The initializer list expression that 1255/// describes all of the subobject initializers in the order they'll 1256/// actually be initialized. 1257/// 1258/// @returns true if there was an error, false otherwise. 1259bool 1260InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, 1261 InitListExpr *IList, 1262 DesignatedInitExpr *DIE, 1263 unsigned DesigIdx, 1264 QualType &CurrentObjectType, 1265 RecordDecl::field_iterator *NextField, 1266 llvm::APSInt *NextElementIndex, 1267 unsigned &Index, 1268 InitListExpr *StructuredList, 1269 unsigned &StructuredIndex, 1270 bool FinishSubobjectInit, 1271 bool TopLevelObject) { 1272 if (DesigIdx == DIE->size()) { 1273 // Check the actual initialization for the designated object type. 1274 bool prevHadError = hadError; 1275 1276 // Temporarily remove the designator expression from the 1277 // initializer list that the child calls see, so that we don't try 1278 // to re-process the designator. 1279 unsigned OldIndex = Index; 1280 IList->setInit(OldIndex, DIE->getInit()); 1281 1282 CheckSubElementType(Entity, IList, CurrentObjectType, Index, 1283 StructuredList, StructuredIndex); 1284 1285 // Restore the designated initializer expression in the syntactic 1286 // form of the initializer list. 1287 if (IList->getInit(OldIndex) != DIE->getInit()) 1288 DIE->setInit(IList->getInit(OldIndex)); 1289 IList->setInit(OldIndex, DIE); 1290 1291 return hadError && !prevHadError; 1292 } 1293 1294 bool IsFirstDesignator = (DesigIdx == 0); 1295 assert((IsFirstDesignator || StructuredList) && 1296 "Need a non-designated initializer list to start from"); 1297 1298 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx); 1299 // Determine the structural initializer list that corresponds to the 1300 // current subobject. 1301 StructuredList = IsFirstDesignator? SyntacticToSemantic[IList] 1302 : getStructuredSubobjectInit(IList, Index, CurrentObjectType, 1303 StructuredList, StructuredIndex, 1304 SourceRange(D->getStartLocation(), 1305 DIE->getSourceRange().getEnd())); 1306 assert(StructuredList && "Expected a structured initializer list"); 1307 1308 if (D->isFieldDesignator()) { 1309 // C99 6.7.8p7: 1310 // 1311 // If a designator has the form 1312 // 1313 // . identifier 1314 // 1315 // then the current object (defined below) shall have 1316 // structure or union type and the identifier shall be the 1317 // name of a member of that type. 1318 const RecordType *RT = CurrentObjectType->getAs<RecordType>(); 1319 if (!RT) { 1320 SourceLocation Loc = D->getDotLoc(); 1321 if (Loc.isInvalid()) 1322 Loc = D->getFieldLoc(); 1323 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr) 1324 << SemaRef.getLangOptions().CPlusPlus << CurrentObjectType; 1325 ++Index; 1326 return true; 1327 } 1328 1329 // Note: we perform a linear search of the fields here, despite 1330 // the fact that we have a faster lookup method, because we always 1331 // need to compute the field's index. 1332 FieldDecl *KnownField = D->getField(); 1333 IdentifierInfo *FieldName = D->getFieldName(); 1334 unsigned FieldIndex = 0; 1335 RecordDecl::field_iterator 1336 Field = RT->getDecl()->field_begin(), 1337 FieldEnd = RT->getDecl()->field_end(); 1338 for (; Field != FieldEnd; ++Field) { 1339 if (Field->isUnnamedBitfield()) 1340 continue; 1341 1342 if (KnownField == *Field || Field->getIdentifier() == FieldName) 1343 break; 1344 1345 ++FieldIndex; 1346 } 1347 1348 if (Field == FieldEnd) { 1349 // There was no normal field in the struct with the designated 1350 // name. Perform another lookup for this name, which may find 1351 // something that we can't designate (e.g., a member function), 1352 // may find nothing, or may find a member of an anonymous 1353 // struct/union. 1354 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName); 1355 FieldDecl *ReplacementField = 0; 1356 if (Lookup.first == Lookup.second) { 1357 // Name lookup didn't find anything. Determine whether this 1358 // was a typo for another field name. 1359 LookupResult R(SemaRef, FieldName, D->getFieldLoc(), 1360 Sema::LookupMemberName); 1361 if (SemaRef.CorrectTypo(R, /*Scope=*/0, /*SS=*/0, RT->getDecl(), false, 1362 Sema::CTC_NoKeywords) && 1363 (ReplacementField = R.getAsSingle<FieldDecl>()) && 1364 ReplacementField->getDeclContext()->getLookupContext() 1365 ->Equals(RT->getDecl())) { 1366 SemaRef.Diag(D->getFieldLoc(), 1367 diag::err_field_designator_unknown_suggest) 1368 << FieldName << CurrentObjectType << R.getLookupName() 1369 << FixItHint::CreateReplacement(D->getFieldLoc(), 1370 R.getLookupName().getAsString()); 1371 SemaRef.Diag(ReplacementField->getLocation(), 1372 diag::note_previous_decl) 1373 << ReplacementField->getDeclName(); 1374 } else { 1375 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown) 1376 << FieldName << CurrentObjectType; 1377 ++Index; 1378 return true; 1379 } 1380 } else if (!KnownField) { 1381 // Determine whether we found a field at all. 1382 ReplacementField = dyn_cast<FieldDecl>(*Lookup.first); 1383 } 1384 1385 if (!ReplacementField) { 1386 // Name lookup found something, but it wasn't a field. 1387 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield) 1388 << FieldName; 1389 SemaRef.Diag((*Lookup.first)->getLocation(), 1390 diag::note_field_designator_found); 1391 ++Index; 1392 return true; 1393 } 1394 1395 if (!KnownField && 1396 cast<RecordDecl>((ReplacementField)->getDeclContext()) 1397 ->isAnonymousStructOrUnion()) { 1398 // Handle an field designator that refers to a member of an 1399 // anonymous struct or union. 1400 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, 1401 ReplacementField, 1402 Field, FieldIndex); 1403 D = DIE->getDesignator(DesigIdx); 1404 } else if (!KnownField) { 1405 // The replacement field comes from typo correction; find it 1406 // in the list of fields. 1407 FieldIndex = 0; 1408 Field = RT->getDecl()->field_begin(); 1409 for (; Field != FieldEnd; ++Field) { 1410 if (Field->isUnnamedBitfield()) 1411 continue; 1412 1413 if (ReplacementField == *Field || 1414 Field->getIdentifier() == ReplacementField->getIdentifier()) 1415 break; 1416 1417 ++FieldIndex; 1418 } 1419 } 1420 } else if (!KnownField && 1421 cast<RecordDecl>((*Field)->getDeclContext()) 1422 ->isAnonymousStructOrUnion()) { 1423 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, *Field, 1424 Field, FieldIndex); 1425 D = DIE->getDesignator(DesigIdx); 1426 } 1427 1428 // All of the fields of a union are located at the same place in 1429 // the initializer list. 1430 if (RT->getDecl()->isUnion()) { 1431 FieldIndex = 0; 1432 StructuredList->setInitializedFieldInUnion(*Field); 1433 } 1434 1435 // Update the designator with the field declaration. 1436 D->setField(*Field); 1437 1438 // Make sure that our non-designated initializer list has space 1439 // for a subobject corresponding to this field. 1440 if (FieldIndex >= StructuredList->getNumInits()) 1441 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1); 1442 1443 // This designator names a flexible array member. 1444 if (Field->getType()->isIncompleteArrayType()) { 1445 bool Invalid = false; 1446 if ((DesigIdx + 1) != DIE->size()) { 1447 // We can't designate an object within the flexible array 1448 // member (because GCC doesn't allow it). 1449 DesignatedInitExpr::Designator *NextD 1450 = DIE->getDesignator(DesigIdx + 1); 1451 SemaRef.Diag(NextD->getStartLocation(), 1452 diag::err_designator_into_flexible_array_member) 1453 << SourceRange(NextD->getStartLocation(), 1454 DIE->getSourceRange().getEnd()); 1455 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1456 << *Field; 1457 Invalid = true; 1458 } 1459 1460 if (!hadError && !isa<InitListExpr>(DIE->getInit())) { 1461 // The initializer is not an initializer list. 1462 SemaRef.Diag(DIE->getInit()->getSourceRange().getBegin(), 1463 diag::err_flexible_array_init_needs_braces) 1464 << DIE->getInit()->getSourceRange(); 1465 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1466 << *Field; 1467 Invalid = true; 1468 } 1469 1470 // Handle GNU flexible array initializers. 1471 if (!Invalid && !TopLevelObject && 1472 cast<InitListExpr>(DIE->getInit())->getNumInits() > 0) { 1473 SemaRef.Diag(DIE->getSourceRange().getBegin(), 1474 diag::err_flexible_array_init_nonempty) 1475 << DIE->getSourceRange().getBegin(); 1476 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1477 << *Field; 1478 Invalid = true; 1479 } 1480 1481 if (Invalid) { 1482 ++Index; 1483 return true; 1484 } 1485 1486 // Initialize the array. 1487 bool prevHadError = hadError; 1488 unsigned newStructuredIndex = FieldIndex; 1489 unsigned OldIndex = Index; 1490 IList->setInit(Index, DIE->getInit()); 1491 1492 InitializedEntity MemberEntity = 1493 InitializedEntity::InitializeMember(*Field, &Entity); 1494 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1495 StructuredList, newStructuredIndex); 1496 1497 IList->setInit(OldIndex, DIE); 1498 if (hadError && !prevHadError) { 1499 ++Field; 1500 ++FieldIndex; 1501 if (NextField) 1502 *NextField = Field; 1503 StructuredIndex = FieldIndex; 1504 return true; 1505 } 1506 } else { 1507 // Recurse to check later designated subobjects. 1508 QualType FieldType = (*Field)->getType(); 1509 unsigned newStructuredIndex = FieldIndex; 1510 1511 InitializedEntity MemberEntity = 1512 InitializedEntity::InitializeMember(*Field, &Entity); 1513 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1, 1514 FieldType, 0, 0, Index, 1515 StructuredList, newStructuredIndex, 1516 true, false)) 1517 return true; 1518 } 1519 1520 // Find the position of the next field to be initialized in this 1521 // subobject. 1522 ++Field; 1523 ++FieldIndex; 1524 1525 // If this the first designator, our caller will continue checking 1526 // the rest of this struct/class/union subobject. 1527 if (IsFirstDesignator) { 1528 if (NextField) 1529 *NextField = Field; 1530 StructuredIndex = FieldIndex; 1531 return false; 1532 } 1533 1534 if (!FinishSubobjectInit) 1535 return false; 1536 1537 // We've already initialized something in the union; we're done. 1538 if (RT->getDecl()->isUnion()) 1539 return hadError; 1540 1541 // Check the remaining fields within this class/struct/union subobject. 1542 bool prevHadError = hadError; 1543 1544 CheckStructUnionTypes(Entity, IList, CurrentObjectType, Field, false, Index, 1545 StructuredList, FieldIndex); 1546 return hadError && !prevHadError; 1547 } 1548 1549 // C99 6.7.8p6: 1550 // 1551 // If a designator has the form 1552 // 1553 // [ constant-expression ] 1554 // 1555 // then the current object (defined below) shall have array 1556 // type and the expression shall be an integer constant 1557 // expression. If the array is of unknown size, any 1558 // nonnegative value is valid. 1559 // 1560 // Additionally, cope with the GNU extension that permits 1561 // designators of the form 1562 // 1563 // [ constant-expression ... constant-expression ] 1564 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType); 1565 if (!AT) { 1566 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array) 1567 << CurrentObjectType; 1568 ++Index; 1569 return true; 1570 } 1571 1572 Expr *IndexExpr = 0; 1573 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex; 1574 if (D->isArrayDesignator()) { 1575 IndexExpr = DIE->getArrayIndex(*D); 1576 DesignatedStartIndex = IndexExpr->EvaluateAsInt(SemaRef.Context); 1577 DesignatedEndIndex = DesignatedStartIndex; 1578 } else { 1579 assert(D->isArrayRangeDesignator() && "Need array-range designator"); 1580 1581 1582 DesignatedStartIndex = 1583 DIE->getArrayRangeStart(*D)->EvaluateAsInt(SemaRef.Context); 1584 DesignatedEndIndex = 1585 DIE->getArrayRangeEnd(*D)->EvaluateAsInt(SemaRef.Context); 1586 IndexExpr = DIE->getArrayRangeEnd(*D); 1587 1588 if (DesignatedStartIndex.getZExtValue() !=DesignatedEndIndex.getZExtValue()) 1589 FullyStructuredList->sawArrayRangeDesignator(); 1590 } 1591 1592 if (isa<ConstantArrayType>(AT)) { 1593 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false); 1594 DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth()); 1595 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned()); 1596 DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth()); 1597 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned()); 1598 if (DesignatedEndIndex >= MaxElements) { 1599 SemaRef.Diag(IndexExpr->getSourceRange().getBegin(), 1600 diag::err_array_designator_too_large) 1601 << DesignatedEndIndex.toString(10) << MaxElements.toString(10) 1602 << IndexExpr->getSourceRange(); 1603 ++Index; 1604 return true; 1605 } 1606 } else { 1607 // Make sure the bit-widths and signedness match. 1608 if (DesignatedStartIndex.getBitWidth() > DesignatedEndIndex.getBitWidth()) 1609 DesignatedEndIndex.extend(DesignatedStartIndex.getBitWidth()); 1610 else if (DesignatedStartIndex.getBitWidth() < 1611 DesignatedEndIndex.getBitWidth()) 1612 DesignatedStartIndex.extend(DesignatedEndIndex.getBitWidth()); 1613 DesignatedStartIndex.setIsUnsigned(true); 1614 DesignatedEndIndex.setIsUnsigned(true); 1615 } 1616 1617 // Make sure that our non-designated initializer list has space 1618 // for a subobject corresponding to this array element. 1619 if (DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits()) 1620 StructuredList->resizeInits(SemaRef.Context, 1621 DesignatedEndIndex.getZExtValue() + 1); 1622 1623 // Repeatedly perform subobject initializations in the range 1624 // [DesignatedStartIndex, DesignatedEndIndex]. 1625 1626 // Move to the next designator 1627 unsigned ElementIndex = DesignatedStartIndex.getZExtValue(); 1628 unsigned OldIndex = Index; 1629 1630 InitializedEntity ElementEntity = 1631 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1632 1633 while (DesignatedStartIndex <= DesignatedEndIndex) { 1634 // Recurse to check later designated subobjects. 1635 QualType ElementType = AT->getElementType(); 1636 Index = OldIndex; 1637 1638 ElementEntity.setElementIndex(ElementIndex); 1639 if (CheckDesignatedInitializer(ElementEntity, IList, DIE, DesigIdx + 1, 1640 ElementType, 0, 0, Index, 1641 StructuredList, ElementIndex, 1642 (DesignatedStartIndex == DesignatedEndIndex), 1643 false)) 1644 return true; 1645 1646 // Move to the next index in the array that we'll be initializing. 1647 ++DesignatedStartIndex; 1648 ElementIndex = DesignatedStartIndex.getZExtValue(); 1649 } 1650 1651 // If this the first designator, our caller will continue checking 1652 // the rest of this array subobject. 1653 if (IsFirstDesignator) { 1654 if (NextElementIndex) 1655 *NextElementIndex = DesignatedStartIndex; 1656 StructuredIndex = ElementIndex; 1657 return false; 1658 } 1659 1660 if (!FinishSubobjectInit) 1661 return false; 1662 1663 // Check the remaining elements within this array subobject. 1664 bool prevHadError = hadError; 1665 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex, 1666 /*SubobjectIsDesignatorContext=*/false, Index, 1667 StructuredList, ElementIndex); 1668 return hadError && !prevHadError; 1669} 1670 1671// Get the structured initializer list for a subobject of type 1672// @p CurrentObjectType. 1673InitListExpr * 1674InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 1675 QualType CurrentObjectType, 1676 InitListExpr *StructuredList, 1677 unsigned StructuredIndex, 1678 SourceRange InitRange) { 1679 Expr *ExistingInit = 0; 1680 if (!StructuredList) 1681 ExistingInit = SyntacticToSemantic[IList]; 1682 else if (StructuredIndex < StructuredList->getNumInits()) 1683 ExistingInit = StructuredList->getInit(StructuredIndex); 1684 1685 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit)) 1686 return Result; 1687 1688 if (ExistingInit) { 1689 // We are creating an initializer list that initializes the 1690 // subobjects of the current object, but there was already an 1691 // initialization that completely initialized the current 1692 // subobject, e.g., by a compound literal: 1693 // 1694 // struct X { int a, b; }; 1695 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 }; 1696 // 1697 // Here, xs[0].a == 0 and xs[0].b == 3, since the second, 1698 // designated initializer re-initializes the whole 1699 // subobject [0], overwriting previous initializers. 1700 SemaRef.Diag(InitRange.getBegin(), 1701 diag::warn_subobject_initializer_overrides) 1702 << InitRange; 1703 SemaRef.Diag(ExistingInit->getSourceRange().getBegin(), 1704 diag::note_previous_initializer) 1705 << /*FIXME:has side effects=*/0 1706 << ExistingInit->getSourceRange(); 1707 } 1708 1709 InitListExpr *Result 1710 = new (SemaRef.Context) InitListExpr(SemaRef.Context, 1711 InitRange.getBegin(), 0, 0, 1712 InitRange.getEnd()); 1713 1714 Result->setType(CurrentObjectType.getNonReferenceType()); 1715 1716 // Pre-allocate storage for the structured initializer list. 1717 unsigned NumElements = 0; 1718 unsigned NumInits = 0; 1719 if (!StructuredList) 1720 NumInits = IList->getNumInits(); 1721 else if (Index < IList->getNumInits()) { 1722 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) 1723 NumInits = SubList->getNumInits(); 1724 } 1725 1726 if (const ArrayType *AType 1727 = SemaRef.Context.getAsArrayType(CurrentObjectType)) { 1728 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) { 1729 NumElements = CAType->getSize().getZExtValue(); 1730 // Simple heuristic so that we don't allocate a very large 1731 // initializer with many empty entries at the end. 1732 if (NumInits && NumElements > NumInits) 1733 NumElements = 0; 1734 } 1735 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>()) 1736 NumElements = VType->getNumElements(); 1737 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) { 1738 RecordDecl *RDecl = RType->getDecl(); 1739 if (RDecl->isUnion()) 1740 NumElements = 1; 1741 else 1742 NumElements = std::distance(RDecl->field_begin(), 1743 RDecl->field_end()); 1744 } 1745 1746 if (NumElements < NumInits) 1747 NumElements = IList->getNumInits(); 1748 1749 Result->reserveInits(SemaRef.Context, NumElements); 1750 1751 // Link this new initializer list into the structured initializer 1752 // lists. 1753 if (StructuredList) 1754 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result); 1755 else { 1756 Result->setSyntacticForm(IList); 1757 SyntacticToSemantic[IList] = Result; 1758 } 1759 1760 return Result; 1761} 1762 1763/// Update the initializer at index @p StructuredIndex within the 1764/// structured initializer list to the value @p expr. 1765void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList, 1766 unsigned &StructuredIndex, 1767 Expr *expr) { 1768 // No structured initializer list to update 1769 if (!StructuredList) 1770 return; 1771 1772 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context, 1773 StructuredIndex, expr)) { 1774 // This initializer overwrites a previous initializer. Warn. 1775 SemaRef.Diag(expr->getSourceRange().getBegin(), 1776 diag::warn_initializer_overrides) 1777 << expr->getSourceRange(); 1778 SemaRef.Diag(PrevInit->getSourceRange().getBegin(), 1779 diag::note_previous_initializer) 1780 << /*FIXME:has side effects=*/0 1781 << PrevInit->getSourceRange(); 1782 } 1783 1784 ++StructuredIndex; 1785} 1786 1787/// Check that the given Index expression is a valid array designator 1788/// value. This is essentailly just a wrapper around 1789/// VerifyIntegerConstantExpression that also checks for negative values 1790/// and produces a reasonable diagnostic if there is a 1791/// failure. Returns true if there was an error, false otherwise. If 1792/// everything went okay, Value will receive the value of the constant 1793/// expression. 1794static bool 1795CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) { 1796 SourceLocation Loc = Index->getSourceRange().getBegin(); 1797 1798 // Make sure this is an integer constant expression. 1799 if (S.VerifyIntegerConstantExpression(Index, &Value)) 1800 return true; 1801 1802 if (Value.isSigned() && Value.isNegative()) 1803 return S.Diag(Loc, diag::err_array_designator_negative) 1804 << Value.toString(10) << Index->getSourceRange(); 1805 1806 Value.setIsUnsigned(true); 1807 return false; 1808} 1809 1810Sema::OwningExprResult Sema::ActOnDesignatedInitializer(Designation &Desig, 1811 SourceLocation Loc, 1812 bool GNUSyntax, 1813 OwningExprResult Init) { 1814 typedef DesignatedInitExpr::Designator ASTDesignator; 1815 1816 bool Invalid = false; 1817 llvm::SmallVector<ASTDesignator, 32> Designators; 1818 llvm::SmallVector<Expr *, 32> InitExpressions; 1819 1820 // Build designators and check array designator expressions. 1821 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) { 1822 const Designator &D = Desig.getDesignator(Idx); 1823 switch (D.getKind()) { 1824 case Designator::FieldDesignator: 1825 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(), 1826 D.getFieldLoc())); 1827 break; 1828 1829 case Designator::ArrayDesignator: { 1830 Expr *Index = static_cast<Expr *>(D.getArrayIndex()); 1831 llvm::APSInt IndexValue; 1832 if (!Index->isTypeDependent() && 1833 !Index->isValueDependent() && 1834 CheckArrayDesignatorExpr(*this, Index, IndexValue)) 1835 Invalid = true; 1836 else { 1837 Designators.push_back(ASTDesignator(InitExpressions.size(), 1838 D.getLBracketLoc(), 1839 D.getRBracketLoc())); 1840 InitExpressions.push_back(Index); 1841 } 1842 break; 1843 } 1844 1845 case Designator::ArrayRangeDesignator: { 1846 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart()); 1847 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd()); 1848 llvm::APSInt StartValue; 1849 llvm::APSInt EndValue; 1850 bool StartDependent = StartIndex->isTypeDependent() || 1851 StartIndex->isValueDependent(); 1852 bool EndDependent = EndIndex->isTypeDependent() || 1853 EndIndex->isValueDependent(); 1854 if ((!StartDependent && 1855 CheckArrayDesignatorExpr(*this, StartIndex, StartValue)) || 1856 (!EndDependent && 1857 CheckArrayDesignatorExpr(*this, EndIndex, EndValue))) 1858 Invalid = true; 1859 else { 1860 // Make sure we're comparing values with the same bit width. 1861 if (StartDependent || EndDependent) { 1862 // Nothing to compute. 1863 } else if (StartValue.getBitWidth() > EndValue.getBitWidth()) 1864 EndValue.extend(StartValue.getBitWidth()); 1865 else if (StartValue.getBitWidth() < EndValue.getBitWidth()) 1866 StartValue.extend(EndValue.getBitWidth()); 1867 1868 if (!StartDependent && !EndDependent && EndValue < StartValue) { 1869 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range) 1870 << StartValue.toString(10) << EndValue.toString(10) 1871 << StartIndex->getSourceRange() << EndIndex->getSourceRange(); 1872 Invalid = true; 1873 } else { 1874 Designators.push_back(ASTDesignator(InitExpressions.size(), 1875 D.getLBracketLoc(), 1876 D.getEllipsisLoc(), 1877 D.getRBracketLoc())); 1878 InitExpressions.push_back(StartIndex); 1879 InitExpressions.push_back(EndIndex); 1880 } 1881 } 1882 break; 1883 } 1884 } 1885 } 1886 1887 if (Invalid || Init.isInvalid()) 1888 return ExprError(); 1889 1890 // Clear out the expressions within the designation. 1891 Desig.ClearExprs(*this); 1892 1893 DesignatedInitExpr *DIE 1894 = DesignatedInitExpr::Create(Context, 1895 Designators.data(), Designators.size(), 1896 InitExpressions.data(), InitExpressions.size(), 1897 Loc, GNUSyntax, Init.takeAs<Expr>()); 1898 return Owned(DIE); 1899} 1900 1901bool Sema::CheckInitList(const InitializedEntity &Entity, 1902 InitListExpr *&InitList, QualType &DeclType) { 1903 InitListChecker CheckInitList(*this, Entity, InitList, DeclType); 1904 if (!CheckInitList.HadError()) 1905 InitList = CheckInitList.getFullyStructuredList(); 1906 1907 return CheckInitList.HadError(); 1908} 1909 1910//===----------------------------------------------------------------------===// 1911// Initialization entity 1912//===----------------------------------------------------------------------===// 1913 1914InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index, 1915 const InitializedEntity &Parent) 1916 : Parent(&Parent), Index(Index) 1917{ 1918 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) { 1919 Kind = EK_ArrayElement; 1920 Type = AT->getElementType(); 1921 } else { 1922 Kind = EK_VectorElement; 1923 Type = Parent.getType()->getAs<VectorType>()->getElementType(); 1924 } 1925} 1926 1927InitializedEntity InitializedEntity::InitializeBase(ASTContext &Context, 1928 CXXBaseSpecifier *Base, 1929 bool IsInheritedVirtualBase) 1930{ 1931 InitializedEntity Result; 1932 Result.Kind = EK_Base; 1933 Result.Base = reinterpret_cast<uintptr_t>(Base); 1934 if (IsInheritedVirtualBase) 1935 Result.Base |= 0x01; 1936 1937 Result.Type = Base->getType(); 1938 return Result; 1939} 1940 1941DeclarationName InitializedEntity::getName() const { 1942 switch (getKind()) { 1943 case EK_Parameter: 1944 if (!VariableOrMember) 1945 return DeclarationName(); 1946 // Fall through 1947 1948 case EK_Variable: 1949 case EK_Member: 1950 return VariableOrMember->getDeclName(); 1951 1952 case EK_Result: 1953 case EK_Exception: 1954 case EK_New: 1955 case EK_Temporary: 1956 case EK_Base: 1957 case EK_ArrayElement: 1958 case EK_VectorElement: 1959 case EK_BlockElement: 1960 return DeclarationName(); 1961 } 1962 1963 // Silence GCC warning 1964 return DeclarationName(); 1965} 1966 1967DeclaratorDecl *InitializedEntity::getDecl() const { 1968 switch (getKind()) { 1969 case EK_Variable: 1970 case EK_Parameter: 1971 case EK_Member: 1972 return VariableOrMember; 1973 1974 case EK_Result: 1975 case EK_Exception: 1976 case EK_New: 1977 case EK_Temporary: 1978 case EK_Base: 1979 case EK_ArrayElement: 1980 case EK_VectorElement: 1981 case EK_BlockElement: 1982 return 0; 1983 } 1984 1985 // Silence GCC warning 1986 return 0; 1987} 1988 1989bool InitializedEntity::allowsNRVO() const { 1990 switch (getKind()) { 1991 case EK_Result: 1992 case EK_Exception: 1993 return LocAndNRVO.NRVO; 1994 1995 case EK_Variable: 1996 case EK_Parameter: 1997 case EK_Member: 1998 case EK_New: 1999 case EK_Temporary: 2000 case EK_Base: 2001 case EK_ArrayElement: 2002 case EK_VectorElement: 2003 case EK_BlockElement: 2004 break; 2005 } 2006 2007 return false; 2008} 2009 2010//===----------------------------------------------------------------------===// 2011// Initialization sequence 2012//===----------------------------------------------------------------------===// 2013 2014void InitializationSequence::Step::Destroy() { 2015 switch (Kind) { 2016 case SK_ResolveAddressOfOverloadedFunction: 2017 case SK_CastDerivedToBaseRValue: 2018 case SK_CastDerivedToBaseLValue: 2019 case SK_BindReference: 2020 case SK_BindReferenceToTemporary: 2021 case SK_ExtraneousCopyToTemporary: 2022 case SK_UserConversion: 2023 case SK_QualificationConversionRValue: 2024 case SK_QualificationConversionLValue: 2025 case SK_ListInitialization: 2026 case SK_ConstructorInitialization: 2027 case SK_ZeroInitialization: 2028 case SK_CAssignment: 2029 case SK_StringInit: 2030 break; 2031 2032 case SK_ConversionSequence: 2033 delete ICS; 2034 } 2035} 2036 2037bool InitializationSequence::isDirectReferenceBinding() const { 2038 return getKind() == ReferenceBinding && Steps.back().Kind == SK_BindReference; 2039} 2040 2041bool InitializationSequence::isAmbiguous() const { 2042 if (getKind() != FailedSequence) 2043 return false; 2044 2045 switch (getFailureKind()) { 2046 case FK_TooManyInitsForReference: 2047 case FK_ArrayNeedsInitList: 2048 case FK_ArrayNeedsInitListOrStringLiteral: 2049 case FK_AddressOfOverloadFailed: // FIXME: Could do better 2050 case FK_NonConstLValueReferenceBindingToTemporary: 2051 case FK_NonConstLValueReferenceBindingToUnrelated: 2052 case FK_RValueReferenceBindingToLValue: 2053 case FK_ReferenceInitDropsQualifiers: 2054 case FK_ReferenceInitFailed: 2055 case FK_ConversionFailed: 2056 case FK_TooManyInitsForScalar: 2057 case FK_ReferenceBindingToInitList: 2058 case FK_InitListBadDestinationType: 2059 case FK_DefaultInitOfConst: 2060 case FK_Incomplete: 2061 return false; 2062 2063 case FK_ReferenceInitOverloadFailed: 2064 case FK_UserConversionOverloadFailed: 2065 case FK_ConstructorOverloadFailed: 2066 return FailedOverloadResult == OR_Ambiguous; 2067 } 2068 2069 return false; 2070} 2071 2072bool InitializationSequence::isConstructorInitialization() const { 2073 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization; 2074} 2075 2076void InitializationSequence::AddAddressOverloadResolutionStep( 2077 FunctionDecl *Function, 2078 DeclAccessPair Found) { 2079 Step S; 2080 S.Kind = SK_ResolveAddressOfOverloadedFunction; 2081 S.Type = Function->getType(); 2082 S.Function.Function = Function; 2083 S.Function.FoundDecl = Found; 2084 Steps.push_back(S); 2085} 2086 2087void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType, 2088 bool IsLValue) { 2089 Step S; 2090 S.Kind = IsLValue? SK_CastDerivedToBaseLValue : SK_CastDerivedToBaseRValue; 2091 S.Type = BaseType; 2092 Steps.push_back(S); 2093} 2094 2095void InitializationSequence::AddReferenceBindingStep(QualType T, 2096 bool BindingTemporary) { 2097 Step S; 2098 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference; 2099 S.Type = T; 2100 Steps.push_back(S); 2101} 2102 2103void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) { 2104 Step S; 2105 S.Kind = SK_ExtraneousCopyToTemporary; 2106 S.Type = T; 2107 Steps.push_back(S); 2108} 2109 2110void InitializationSequence::AddUserConversionStep(FunctionDecl *Function, 2111 DeclAccessPair FoundDecl, 2112 QualType T) { 2113 Step S; 2114 S.Kind = SK_UserConversion; 2115 S.Type = T; 2116 S.Function.Function = Function; 2117 S.Function.FoundDecl = FoundDecl; 2118 Steps.push_back(S); 2119} 2120 2121void InitializationSequence::AddQualificationConversionStep(QualType Ty, 2122 bool IsLValue) { 2123 Step S; 2124 S.Kind = IsLValue? SK_QualificationConversionLValue 2125 : SK_QualificationConversionRValue; 2126 S.Type = Ty; 2127 Steps.push_back(S); 2128} 2129 2130void InitializationSequence::AddConversionSequenceStep( 2131 const ImplicitConversionSequence &ICS, 2132 QualType T) { 2133 Step S; 2134 S.Kind = SK_ConversionSequence; 2135 S.Type = T; 2136 S.ICS = new ImplicitConversionSequence(ICS); 2137 Steps.push_back(S); 2138} 2139 2140void InitializationSequence::AddListInitializationStep(QualType T) { 2141 Step S; 2142 S.Kind = SK_ListInitialization; 2143 S.Type = T; 2144 Steps.push_back(S); 2145} 2146 2147void 2148InitializationSequence::AddConstructorInitializationStep( 2149 CXXConstructorDecl *Constructor, 2150 AccessSpecifier Access, 2151 QualType T) { 2152 Step S; 2153 S.Kind = SK_ConstructorInitialization; 2154 S.Type = T; 2155 S.Function.Function = Constructor; 2156 S.Function.FoundDecl = DeclAccessPair::make(Constructor, Access); 2157 Steps.push_back(S); 2158} 2159 2160void InitializationSequence::AddZeroInitializationStep(QualType T) { 2161 Step S; 2162 S.Kind = SK_ZeroInitialization; 2163 S.Type = T; 2164 Steps.push_back(S); 2165} 2166 2167void InitializationSequence::AddCAssignmentStep(QualType T) { 2168 Step S; 2169 S.Kind = SK_CAssignment; 2170 S.Type = T; 2171 Steps.push_back(S); 2172} 2173 2174void InitializationSequence::AddStringInitStep(QualType T) { 2175 Step S; 2176 S.Kind = SK_StringInit; 2177 S.Type = T; 2178 Steps.push_back(S); 2179} 2180 2181void InitializationSequence::SetOverloadFailure(FailureKind Failure, 2182 OverloadingResult Result) { 2183 SequenceKind = FailedSequence; 2184 this->Failure = Failure; 2185 this->FailedOverloadResult = Result; 2186} 2187 2188//===----------------------------------------------------------------------===// 2189// Attempt initialization 2190//===----------------------------------------------------------------------===// 2191 2192/// \brief Attempt list initialization (C++0x [dcl.init.list]) 2193static void TryListInitialization(Sema &S, 2194 const InitializedEntity &Entity, 2195 const InitializationKind &Kind, 2196 InitListExpr *InitList, 2197 InitializationSequence &Sequence) { 2198 // FIXME: We only perform rudimentary checking of list 2199 // initializations at this point, then assume that any list 2200 // initialization of an array, aggregate, or scalar will be 2201 // well-formed. When we actually "perform" list initialization, we'll 2202 // do all of the necessary checking. C++0x initializer lists will 2203 // force us to perform more checking here. 2204 Sequence.setSequenceKind(InitializationSequence::ListInitialization); 2205 2206 QualType DestType = Entity.getType(); 2207 2208 // C++ [dcl.init]p13: 2209 // If T is a scalar type, then a declaration of the form 2210 // 2211 // T x = { a }; 2212 // 2213 // is equivalent to 2214 // 2215 // T x = a; 2216 if (DestType->isScalarType()) { 2217 if (InitList->getNumInits() > 1 && S.getLangOptions().CPlusPlus) { 2218 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar); 2219 return; 2220 } 2221 2222 // Assume scalar initialization from a single value works. 2223 } else if (DestType->isAggregateType()) { 2224 // Assume aggregate initialization works. 2225 } else if (DestType->isVectorType()) { 2226 // Assume vector initialization works. 2227 } else if (DestType->isReferenceType()) { 2228 // FIXME: C++0x defines behavior for this. 2229 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList); 2230 return; 2231 } else if (DestType->isRecordType()) { 2232 // FIXME: C++0x defines behavior for this 2233 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType); 2234 } 2235 2236 // Add a general "list initialization" step. 2237 Sequence.AddListInitializationStep(DestType); 2238} 2239 2240/// \brief Try a reference initialization that involves calling a conversion 2241/// function. 2242/// 2243/// FIXME: look intos DRs 656, 896 2244static OverloadingResult TryRefInitWithConversionFunction(Sema &S, 2245 const InitializedEntity &Entity, 2246 const InitializationKind &Kind, 2247 Expr *Initializer, 2248 bool AllowRValues, 2249 InitializationSequence &Sequence) { 2250 QualType DestType = Entity.getType(); 2251 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 2252 QualType T1 = cv1T1.getUnqualifiedType(); 2253 QualType cv2T2 = Initializer->getType(); 2254 QualType T2 = cv2T2.getUnqualifiedType(); 2255 2256 bool DerivedToBase; 2257 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(), 2258 T1, T2, DerivedToBase) && 2259 "Must have incompatible references when binding via conversion"); 2260 (void)DerivedToBase; 2261 2262 // Build the candidate set directly in the initialization sequence 2263 // structure, so that it will persist if we fail. 2264 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2265 CandidateSet.clear(); 2266 2267 // Determine whether we are allowed to call explicit constructors or 2268 // explicit conversion operators. 2269 bool AllowExplicit = Kind.getKind() == InitializationKind::IK_Direct; 2270 2271 const RecordType *T1RecordType = 0; 2272 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) && 2273 !S.RequireCompleteType(Kind.getLocation(), T1, 0)) { 2274 // The type we're converting to is a class type. Enumerate its constructors 2275 // to see if there is a suitable conversion. 2276 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl()); 2277 DeclarationName ConstructorName 2278 = S.Context.DeclarationNames.getCXXConstructorName( 2279 S.Context.getCanonicalType(T1).getUnqualifiedType()); 2280 DeclContext::lookup_iterator Con, ConEnd; 2281 for (llvm::tie(Con, ConEnd) = T1RecordDecl->lookup(ConstructorName); 2282 Con != ConEnd; ++Con) { 2283 NamedDecl *D = *Con; 2284 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2285 2286 // Find the constructor (which may be a template). 2287 CXXConstructorDecl *Constructor = 0; 2288 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 2289 if (ConstructorTmpl) 2290 Constructor = cast<CXXConstructorDecl>( 2291 ConstructorTmpl->getTemplatedDecl()); 2292 else 2293 Constructor = cast<CXXConstructorDecl>(D); 2294 2295 if (!Constructor->isInvalidDecl() && 2296 Constructor->isConvertingConstructor(AllowExplicit)) { 2297 if (ConstructorTmpl) 2298 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2299 /*ExplicitArgs*/ 0, 2300 &Initializer, 1, CandidateSet); 2301 else 2302 S.AddOverloadCandidate(Constructor, FoundDecl, 2303 &Initializer, 1, CandidateSet); 2304 } 2305 } 2306 } 2307 2308 const RecordType *T2RecordType = 0; 2309 if ((T2RecordType = T2->getAs<RecordType>()) && 2310 !S.RequireCompleteType(Kind.getLocation(), T2, 0)) { 2311 // The type we're converting from is a class type, enumerate its conversion 2312 // functions. 2313 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl()); 2314 2315 // Determine the type we are converting to. If we are allowed to 2316 // convert to an rvalue, take the type that the destination type 2317 // refers to. 2318 QualType ToType = AllowRValues? cv1T1 : DestType; 2319 2320 const UnresolvedSetImpl *Conversions 2321 = T2RecordDecl->getVisibleConversionFunctions(); 2322 for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), 2323 E = Conversions->end(); I != E; ++I) { 2324 NamedDecl *D = *I; 2325 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 2326 if (isa<UsingShadowDecl>(D)) 2327 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2328 2329 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 2330 CXXConversionDecl *Conv; 2331 if (ConvTemplate) 2332 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2333 else 2334 Conv = cast<CXXConversionDecl>(*I); 2335 2336 // If the conversion function doesn't return a reference type, 2337 // it can't be considered for this conversion unless we're allowed to 2338 // consider rvalues. 2339 // FIXME: Do we need to make sure that we only consider conversion 2340 // candidates with reference-compatible results? That might be needed to 2341 // break recursion. 2342 if ((AllowExplicit || !Conv->isExplicit()) && 2343 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){ 2344 if (ConvTemplate) 2345 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 2346 ActingDC, Initializer, 2347 ToType, CandidateSet); 2348 else 2349 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 2350 Initializer, ToType, CandidateSet); 2351 } 2352 } 2353 } 2354 2355 SourceLocation DeclLoc = Initializer->getLocStart(); 2356 2357 // Perform overload resolution. If it fails, return the failed result. 2358 OverloadCandidateSet::iterator Best; 2359 if (OverloadingResult Result 2360 = S.BestViableFunction(CandidateSet, DeclLoc, Best)) 2361 return Result; 2362 2363 FunctionDecl *Function = Best->Function; 2364 2365 // Compute the returned type of the conversion. 2366 if (isa<CXXConversionDecl>(Function)) 2367 T2 = Function->getResultType(); 2368 else 2369 T2 = cv1T1; 2370 2371 // Add the user-defined conversion step. 2372 Sequence.AddUserConversionStep(Function, Best->FoundDecl, 2373 T2.getNonReferenceType()); 2374 2375 // Determine whether we need to perform derived-to-base or 2376 // cv-qualification adjustments. 2377 bool NewDerivedToBase = false; 2378 Sema::ReferenceCompareResult NewRefRelationship 2379 = S.CompareReferenceRelationship(DeclLoc, T1, T2.getNonReferenceType(), 2380 NewDerivedToBase); 2381 if (NewRefRelationship == Sema::Ref_Incompatible) { 2382 // If the type we've converted to is not reference-related to the 2383 // type we're looking for, then there is another conversion step 2384 // we need to perform to produce a temporary of the right type 2385 // that we'll be binding to. 2386 ImplicitConversionSequence ICS; 2387 ICS.setStandard(); 2388 ICS.Standard = Best->FinalConversion; 2389 T2 = ICS.Standard.getToType(2); 2390 Sequence.AddConversionSequenceStep(ICS, T2); 2391 } else if (NewDerivedToBase) 2392 Sequence.AddDerivedToBaseCastStep( 2393 S.Context.getQualifiedType(T1, 2394 T2.getNonReferenceType().getQualifiers()), 2395 /*isLValue=*/true); 2396 2397 if (cv1T1.getQualifiers() != T2.getNonReferenceType().getQualifiers()) 2398 Sequence.AddQualificationConversionStep(cv1T1, T2->isReferenceType()); 2399 2400 Sequence.AddReferenceBindingStep(cv1T1, !T2->isReferenceType()); 2401 return OR_Success; 2402} 2403 2404/// \brief Attempt reference initialization (C++0x [dcl.init.list]) 2405static void TryReferenceInitialization(Sema &S, 2406 const InitializedEntity &Entity, 2407 const InitializationKind &Kind, 2408 Expr *Initializer, 2409 InitializationSequence &Sequence) { 2410 Sequence.setSequenceKind(InitializationSequence::ReferenceBinding); 2411 2412 QualType DestType = Entity.getType(); 2413 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 2414 Qualifiers T1Quals; 2415 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); 2416 QualType cv2T2 = Initializer->getType(); 2417 Qualifiers T2Quals; 2418 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); 2419 SourceLocation DeclLoc = Initializer->getLocStart(); 2420 2421 // If the initializer is the address of an overloaded function, try 2422 // to resolve the overloaded function. If all goes well, T2 is the 2423 // type of the resulting function. 2424 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 2425 DeclAccessPair Found; 2426 FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Initializer, 2427 T1, 2428 false, 2429 Found); 2430 if (!Fn) { 2431 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 2432 return; 2433 } 2434 2435 Sequence.AddAddressOverloadResolutionStep(Fn, Found); 2436 cv2T2 = Fn->getType(); 2437 T2 = cv2T2.getUnqualifiedType(); 2438 } 2439 2440 // Compute some basic properties of the types and the initializer. 2441 bool isLValueRef = DestType->isLValueReferenceType(); 2442 bool isRValueRef = !isLValueRef; 2443 bool DerivedToBase = false; 2444 Expr::isLvalueResult InitLvalue = Initializer->isLvalue(S.Context); 2445 Sema::ReferenceCompareResult RefRelationship 2446 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase); 2447 2448 // C++0x [dcl.init.ref]p5: 2449 // A reference to type "cv1 T1" is initialized by an expression of type 2450 // "cv2 T2" as follows: 2451 // 2452 // - If the reference is an lvalue reference and the initializer 2453 // expression 2454 OverloadingResult ConvOvlResult = OR_Success; 2455 if (isLValueRef) { 2456 if (InitLvalue == Expr::LV_Valid && 2457 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 2458 // - is an lvalue (but is not a bit-field), and "cv1 T1" is 2459 // reference-compatible with "cv2 T2," or 2460 // 2461 // Per C++ [over.best.ics]p2, we don't diagnose whether the lvalue is a 2462 // bit-field when we're determining whether the reference initialization 2463 // can occur. However, we do pay attention to whether it is a bit-field 2464 // to decide whether we're actually binding to a temporary created from 2465 // the bit-field. 2466 if (DerivedToBase) 2467 Sequence.AddDerivedToBaseCastStep( 2468 S.Context.getQualifiedType(T1, T2Quals), 2469 /*isLValue=*/true); 2470 if (T1Quals != T2Quals) 2471 Sequence.AddQualificationConversionStep(cv1T1, /*IsLValue=*/true); 2472 bool BindingTemporary = T1Quals.hasConst() && !T1Quals.hasVolatile() && 2473 (Initializer->getBitField() || Initializer->refersToVectorElement()); 2474 Sequence.AddReferenceBindingStep(cv1T1, BindingTemporary); 2475 return; 2476 } 2477 2478 // - has a class type (i.e., T2 is a class type), where T1 is not 2479 // reference-related to T2, and can be implicitly converted to an 2480 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible 2481 // with "cv3 T3" (this conversion is selected by enumerating the 2482 // applicable conversion functions (13.3.1.6) and choosing the best 2483 // one through overload resolution (13.3)), 2484 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType()) { 2485 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, Kind, 2486 Initializer, 2487 /*AllowRValues=*/false, 2488 Sequence); 2489 if (ConvOvlResult == OR_Success) 2490 return; 2491 if (ConvOvlResult != OR_No_Viable_Function) { 2492 Sequence.SetOverloadFailure( 2493 InitializationSequence::FK_ReferenceInitOverloadFailed, 2494 ConvOvlResult); 2495 } 2496 } 2497 } 2498 2499 // - Otherwise, the reference shall be an lvalue reference to a 2500 // non-volatile const type (i.e., cv1 shall be const), or the reference 2501 // shall be an rvalue reference and the initializer expression shall 2502 // be an rvalue. 2503 if (!((isLValueRef && T1Quals.hasConst() && !T1Quals.hasVolatile()) || 2504 (isRValueRef && InitLvalue != Expr::LV_Valid))) { 2505 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 2506 Sequence.SetOverloadFailure( 2507 InitializationSequence::FK_ReferenceInitOverloadFailed, 2508 ConvOvlResult); 2509 else if (isLValueRef) 2510 Sequence.SetFailed(InitLvalue == Expr::LV_Valid 2511 ? (RefRelationship == Sema::Ref_Related 2512 ? InitializationSequence::FK_ReferenceInitDropsQualifiers 2513 : InitializationSequence::FK_NonConstLValueReferenceBindingToUnrelated) 2514 : InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); 2515 else 2516 Sequence.SetFailed( 2517 InitializationSequence::FK_RValueReferenceBindingToLValue); 2518 2519 return; 2520 } 2521 2522 // - If T1 and T2 are class types and 2523 if (T1->isRecordType() && T2->isRecordType()) { 2524 // - the initializer expression is an rvalue and "cv1 T1" is 2525 // reference-compatible with "cv2 T2", or 2526 if (InitLvalue != Expr::LV_Valid && 2527 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 2528 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the 2529 // compiler the freedom to perform a copy here or bind to the 2530 // object, while C++0x requires that we bind directly to the 2531 // object. Hence, we always bind to the object without making an 2532 // extra copy. However, in C++03 requires that we check for the 2533 // presence of a suitable copy constructor: 2534 // 2535 // The constructor that would be used to make the copy shall 2536 // be callable whether or not the copy is actually done. 2537 if (!S.getLangOptions().CPlusPlus0x) 2538 Sequence.AddExtraneousCopyToTemporary(cv2T2); 2539 2540 if (DerivedToBase) 2541 Sequence.AddDerivedToBaseCastStep( 2542 S.Context.getQualifiedType(T1, T2Quals), 2543 /*isLValue=*/false); 2544 if (T1Quals != T2Quals) 2545 Sequence.AddQualificationConversionStep(cv1T1, /*IsLValue=*/false); 2546 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 2547 return; 2548 } 2549 2550 // - T1 is not reference-related to T2 and the initializer expression 2551 // can be implicitly converted to an rvalue of type "cv3 T3" (this 2552 // conversion is selected by enumerating the applicable conversion 2553 // functions (13.3.1.6) and choosing the best one through overload 2554 // resolution (13.3)), 2555 if (RefRelationship == Sema::Ref_Incompatible) { 2556 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, 2557 Kind, Initializer, 2558 /*AllowRValues=*/true, 2559 Sequence); 2560 if (ConvOvlResult) 2561 Sequence.SetOverloadFailure( 2562 InitializationSequence::FK_ReferenceInitOverloadFailed, 2563 ConvOvlResult); 2564 2565 return; 2566 } 2567 2568 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 2569 return; 2570 } 2571 2572 // - If the initializer expression is an rvalue, with T2 an array type, 2573 // and "cv1 T1" is reference-compatible with "cv2 T2," the reference 2574 // is bound to the object represented by the rvalue (see 3.10). 2575 // FIXME: How can an array type be reference-compatible with anything? 2576 // Don't we mean the element types of T1 and T2? 2577 2578 // - Otherwise, a temporary of type “cv1 T1” is created and initialized 2579 // from the initializer expression using the rules for a non-reference 2580 // copy initialization (8.5). The reference is then bound to the 2581 // temporary. [...] 2582 2583 // Determine whether we are allowed to call explicit constructors or 2584 // explicit conversion operators. 2585 bool AllowExplicit = (Kind.getKind() == InitializationKind::IK_Direct); 2586 2587 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); 2588 2589 if (S.TryImplicitConversion(Sequence, TempEntity, Initializer, 2590 /*SuppressUserConversions*/ false, 2591 AllowExplicit, 2592 /*FIXME:InOverloadResolution=*/false)) { 2593 // FIXME: Use the conversion function set stored in ICS to turn 2594 // this into an overloading ambiguity diagnostic. However, we need 2595 // to keep that set as an OverloadCandidateSet rather than as some 2596 // other kind of set. 2597 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 2598 Sequence.SetOverloadFailure( 2599 InitializationSequence::FK_ReferenceInitOverloadFailed, 2600 ConvOvlResult); 2601 else 2602 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed); 2603 return; 2604 } 2605 2606 // [...] If T1 is reference-related to T2, cv1 must be the 2607 // same cv-qualification as, or greater cv-qualification 2608 // than, cv2; otherwise, the program is ill-formed. 2609 unsigned T1CVRQuals = T1Quals.getCVRQualifiers(); 2610 unsigned T2CVRQuals = T2Quals.getCVRQualifiers(); 2611 if (RefRelationship == Sema::Ref_Related && 2612 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) { 2613 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 2614 return; 2615 } 2616 2617 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 2618 return; 2619} 2620 2621/// \brief Attempt character array initialization from a string literal 2622/// (C++ [dcl.init.string], C99 6.7.8). 2623static void TryStringLiteralInitialization(Sema &S, 2624 const InitializedEntity &Entity, 2625 const InitializationKind &Kind, 2626 Expr *Initializer, 2627 InitializationSequence &Sequence) { 2628 Sequence.setSequenceKind(InitializationSequence::StringInit); 2629 Sequence.AddStringInitStep(Entity.getType()); 2630} 2631 2632/// \brief Attempt initialization by constructor (C++ [dcl.init]), which 2633/// enumerates the constructors of the initialized entity and performs overload 2634/// resolution to select the best. 2635static void TryConstructorInitialization(Sema &S, 2636 const InitializedEntity &Entity, 2637 const InitializationKind &Kind, 2638 Expr **Args, unsigned NumArgs, 2639 QualType DestType, 2640 InitializationSequence &Sequence) { 2641 Sequence.setSequenceKind(InitializationSequence::ConstructorInitialization); 2642 2643 // Build the candidate set directly in the initialization sequence 2644 // structure, so that it will persist if we fail. 2645 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2646 CandidateSet.clear(); 2647 2648 // Determine whether we are allowed to call explicit constructors or 2649 // explicit conversion operators. 2650 bool AllowExplicit = (Kind.getKind() == InitializationKind::IK_Direct || 2651 Kind.getKind() == InitializationKind::IK_Value || 2652 Kind.getKind() == InitializationKind::IK_Default); 2653 2654 // The type we're constructing needs to be complete. 2655 if (S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { 2656 Sequence.SetFailed(InitializationSequence::FK_Incomplete); 2657 return; 2658 } 2659 2660 // The type we're converting to is a class type. Enumerate its constructors 2661 // to see if one is suitable. 2662 const RecordType *DestRecordType = DestType->getAs<RecordType>(); 2663 assert(DestRecordType && "Constructor initialization requires record type"); 2664 CXXRecordDecl *DestRecordDecl 2665 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 2666 2667 DeclarationName ConstructorName 2668 = S.Context.DeclarationNames.getCXXConstructorName( 2669 S.Context.getCanonicalType(DestType).getUnqualifiedType()); 2670 DeclContext::lookup_iterator Con, ConEnd; 2671 for (llvm::tie(Con, ConEnd) = DestRecordDecl->lookup(ConstructorName); 2672 Con != ConEnd; ++Con) { 2673 NamedDecl *D = *Con; 2674 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2675 bool SuppressUserConversions = false; 2676 2677 // Find the constructor (which may be a template). 2678 CXXConstructorDecl *Constructor = 0; 2679 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 2680 if (ConstructorTmpl) 2681 Constructor = cast<CXXConstructorDecl>( 2682 ConstructorTmpl->getTemplatedDecl()); 2683 else { 2684 Constructor = cast<CXXConstructorDecl>(D); 2685 2686 // If we're performing copy initialization using a copy constructor, we 2687 // suppress user-defined conversions on the arguments. 2688 // FIXME: Move constructors? 2689 if (Kind.getKind() == InitializationKind::IK_Copy && 2690 Constructor->isCopyConstructor()) 2691 SuppressUserConversions = true; 2692 } 2693 2694 if (!Constructor->isInvalidDecl() && 2695 (AllowExplicit || !Constructor->isExplicit())) { 2696 if (ConstructorTmpl) 2697 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2698 /*ExplicitArgs*/ 0, 2699 Args, NumArgs, CandidateSet, 2700 SuppressUserConversions); 2701 else 2702 S.AddOverloadCandidate(Constructor, FoundDecl, 2703 Args, NumArgs, CandidateSet, 2704 SuppressUserConversions); 2705 } 2706 } 2707 2708 SourceLocation DeclLoc = Kind.getLocation(); 2709 2710 // Perform overload resolution. If it fails, return the failed result. 2711 OverloadCandidateSet::iterator Best; 2712 if (OverloadingResult Result 2713 = S.BestViableFunction(CandidateSet, DeclLoc, Best)) { 2714 Sequence.SetOverloadFailure( 2715 InitializationSequence::FK_ConstructorOverloadFailed, 2716 Result); 2717 return; 2718 } 2719 2720 // C++0x [dcl.init]p6: 2721 // If a program calls for the default initialization of an object 2722 // of a const-qualified type T, T shall be a class type with a 2723 // user-provided default constructor. 2724 if (Kind.getKind() == InitializationKind::IK_Default && 2725 Entity.getType().isConstQualified() && 2726 cast<CXXConstructorDecl>(Best->Function)->isImplicit()) { 2727 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 2728 return; 2729 } 2730 2731 // Add the constructor initialization step. Any cv-qualification conversion is 2732 // subsumed by the initialization. 2733 Sequence.AddConstructorInitializationStep( 2734 cast<CXXConstructorDecl>(Best->Function), 2735 Best->FoundDecl.getAccess(), 2736 DestType); 2737} 2738 2739/// \brief Attempt value initialization (C++ [dcl.init]p7). 2740static void TryValueInitialization(Sema &S, 2741 const InitializedEntity &Entity, 2742 const InitializationKind &Kind, 2743 InitializationSequence &Sequence) { 2744 // C++ [dcl.init]p5: 2745 // 2746 // To value-initialize an object of type T means: 2747 QualType T = Entity.getType(); 2748 2749 // -- if T is an array type, then each element is value-initialized; 2750 while (const ArrayType *AT = S.Context.getAsArrayType(T)) 2751 T = AT->getElementType(); 2752 2753 if (const RecordType *RT = T->getAs<RecordType>()) { 2754 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 2755 // -- if T is a class type (clause 9) with a user-declared 2756 // constructor (12.1), then the default constructor for T is 2757 // called (and the initialization is ill-formed if T has no 2758 // accessible default constructor); 2759 // 2760 // FIXME: we really want to refer to a single subobject of the array, 2761 // but Entity doesn't have a way to capture that (yet). 2762 if (ClassDecl->hasUserDeclaredConstructor()) 2763 return TryConstructorInitialization(S, Entity, Kind, 0, 0, T, Sequence); 2764 2765 // -- if T is a (possibly cv-qualified) non-union class type 2766 // without a user-provided constructor, then the object is 2767 // zero-initialized and, if T’s implicitly-declared default 2768 // constructor is non-trivial, that constructor is called. 2769 if ((ClassDecl->getTagKind() == TTK_Class || 2770 ClassDecl->getTagKind() == TTK_Struct) && 2771 !ClassDecl->hasTrivialConstructor()) { 2772 Sequence.AddZeroInitializationStep(Entity.getType()); 2773 return TryConstructorInitialization(S, Entity, Kind, 0, 0, T, Sequence); 2774 } 2775 } 2776 } 2777 2778 Sequence.AddZeroInitializationStep(Entity.getType()); 2779 Sequence.setSequenceKind(InitializationSequence::ZeroInitialization); 2780} 2781 2782/// \brief Attempt default initialization (C++ [dcl.init]p6). 2783static void TryDefaultInitialization(Sema &S, 2784 const InitializedEntity &Entity, 2785 const InitializationKind &Kind, 2786 InitializationSequence &Sequence) { 2787 assert(Kind.getKind() == InitializationKind::IK_Default); 2788 2789 // C++ [dcl.init]p6: 2790 // To default-initialize an object of type T means: 2791 // - if T is an array type, each element is default-initialized; 2792 QualType DestType = Entity.getType(); 2793 while (const ArrayType *Array = S.Context.getAsArrayType(DestType)) 2794 DestType = Array->getElementType(); 2795 2796 // - if T is a (possibly cv-qualified) class type (Clause 9), the default 2797 // constructor for T is called (and the initialization is ill-formed if 2798 // T has no accessible default constructor); 2799 if (DestType->isRecordType() && S.getLangOptions().CPlusPlus) { 2800 return TryConstructorInitialization(S, Entity, Kind, 0, 0, DestType, 2801 Sequence); 2802 } 2803 2804 // - otherwise, no initialization is performed. 2805 Sequence.setSequenceKind(InitializationSequence::NoInitialization); 2806 2807 // If a program calls for the default initialization of an object of 2808 // a const-qualified type T, T shall be a class type with a user-provided 2809 // default constructor. 2810 if (DestType.isConstQualified() && S.getLangOptions().CPlusPlus) 2811 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 2812} 2813 2814/// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]), 2815/// which enumerates all conversion functions and performs overload resolution 2816/// to select the best. 2817static void TryUserDefinedConversion(Sema &S, 2818 const InitializedEntity &Entity, 2819 const InitializationKind &Kind, 2820 Expr *Initializer, 2821 InitializationSequence &Sequence) { 2822 Sequence.setSequenceKind(InitializationSequence::UserDefinedConversion); 2823 2824 QualType DestType = Entity.getType(); 2825 assert(!DestType->isReferenceType() && "References are handled elsewhere"); 2826 QualType SourceType = Initializer->getType(); 2827 assert((DestType->isRecordType() || SourceType->isRecordType()) && 2828 "Must have a class type to perform a user-defined conversion"); 2829 2830 // Build the candidate set directly in the initialization sequence 2831 // structure, so that it will persist if we fail. 2832 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2833 CandidateSet.clear(); 2834 2835 // Determine whether we are allowed to call explicit constructors or 2836 // explicit conversion operators. 2837 bool AllowExplicit = Kind.getKind() == InitializationKind::IK_Direct; 2838 2839 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) { 2840 // The type we're converting to is a class type. Enumerate its constructors 2841 // to see if there is a suitable conversion. 2842 CXXRecordDecl *DestRecordDecl 2843 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 2844 2845 // Try to complete the type we're converting to. 2846 if (!S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { 2847 DeclarationName ConstructorName 2848 = S.Context.DeclarationNames.getCXXConstructorName( 2849 S.Context.getCanonicalType(DestType).getUnqualifiedType()); 2850 DeclContext::lookup_iterator Con, ConEnd; 2851 for (llvm::tie(Con, ConEnd) = DestRecordDecl->lookup(ConstructorName); 2852 Con != ConEnd; ++Con) { 2853 NamedDecl *D = *Con; 2854 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2855 bool SuppressUserConversions = false; 2856 2857 // Find the constructor (which may be a template). 2858 CXXConstructorDecl *Constructor = 0; 2859 FunctionTemplateDecl *ConstructorTmpl 2860 = dyn_cast<FunctionTemplateDecl>(D); 2861 if (ConstructorTmpl) 2862 Constructor = cast<CXXConstructorDecl>( 2863 ConstructorTmpl->getTemplatedDecl()); 2864 else { 2865 Constructor = cast<CXXConstructorDecl>(D); 2866 2867 // If we're performing copy initialization using a copy constructor, 2868 // we suppress user-defined conversions on the arguments. 2869 // FIXME: Move constructors? 2870 if (Kind.getKind() == InitializationKind::IK_Copy && 2871 Constructor->isCopyConstructor()) 2872 SuppressUserConversions = true; 2873 2874 } 2875 2876 if (!Constructor->isInvalidDecl() && 2877 Constructor->isConvertingConstructor(AllowExplicit)) { 2878 if (ConstructorTmpl) 2879 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2880 /*ExplicitArgs*/ 0, 2881 &Initializer, 1, CandidateSet, 2882 SuppressUserConversions); 2883 else 2884 S.AddOverloadCandidate(Constructor, FoundDecl, 2885 &Initializer, 1, CandidateSet, 2886 SuppressUserConversions); 2887 } 2888 } 2889 } 2890 } 2891 2892 SourceLocation DeclLoc = Initializer->getLocStart(); 2893 2894 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) { 2895 // The type we're converting from is a class type, enumerate its conversion 2896 // functions. 2897 2898 // We can only enumerate the conversion functions for a complete type; if 2899 // the type isn't complete, simply skip this step. 2900 if (!S.RequireCompleteType(DeclLoc, SourceType, 0)) { 2901 CXXRecordDecl *SourceRecordDecl 2902 = cast<CXXRecordDecl>(SourceRecordType->getDecl()); 2903 2904 const UnresolvedSetImpl *Conversions 2905 = SourceRecordDecl->getVisibleConversionFunctions(); 2906 for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), 2907 E = Conversions->end(); 2908 I != E; ++I) { 2909 NamedDecl *D = *I; 2910 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 2911 if (isa<UsingShadowDecl>(D)) 2912 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2913 2914 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 2915 CXXConversionDecl *Conv; 2916 if (ConvTemplate) 2917 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2918 else 2919 Conv = cast<CXXConversionDecl>(D); 2920 2921 if (AllowExplicit || !Conv->isExplicit()) { 2922 if (ConvTemplate) 2923 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 2924 ActingDC, Initializer, DestType, 2925 CandidateSet); 2926 else 2927 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 2928 Initializer, DestType, CandidateSet); 2929 } 2930 } 2931 } 2932 } 2933 2934 // Perform overload resolution. If it fails, return the failed result. 2935 OverloadCandidateSet::iterator Best; 2936 if (OverloadingResult Result 2937 = S.BestViableFunction(CandidateSet, DeclLoc, Best)) { 2938 Sequence.SetOverloadFailure( 2939 InitializationSequence::FK_UserConversionOverloadFailed, 2940 Result); 2941 return; 2942 } 2943 2944 FunctionDecl *Function = Best->Function; 2945 2946 if (isa<CXXConstructorDecl>(Function)) { 2947 // Add the user-defined conversion step. Any cv-qualification conversion is 2948 // subsumed by the initialization. 2949 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType); 2950 return; 2951 } 2952 2953 // Add the user-defined conversion step that calls the conversion function. 2954 QualType ConvType = Function->getResultType().getNonReferenceType(); 2955 if (ConvType->getAs<RecordType>()) { 2956 // If we're converting to a class type, there may be an copy if 2957 // the resulting temporary object (possible to create an object of 2958 // a base class type). That copy is not a separate conversion, so 2959 // we just make a note of the actual destination type (possibly a 2960 // base class of the type returned by the conversion function) and 2961 // let the user-defined conversion step handle the conversion. 2962 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType); 2963 return; 2964 } 2965 2966 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType); 2967 2968 // If the conversion following the call to the conversion function 2969 // is interesting, add it as a separate step. 2970 if (Best->FinalConversion.First || Best->FinalConversion.Second || 2971 Best->FinalConversion.Third) { 2972 ImplicitConversionSequence ICS; 2973 ICS.setStandard(); 2974 ICS.Standard = Best->FinalConversion; 2975 Sequence.AddConversionSequenceStep(ICS, DestType); 2976 } 2977} 2978 2979bool Sema::TryImplicitConversion(InitializationSequence &Sequence, 2980 const InitializedEntity &Entity, 2981 Expr *Initializer, 2982 bool SuppressUserConversions, 2983 bool AllowExplicitConversions, 2984 bool InOverloadResolution) { 2985 ImplicitConversionSequence ICS 2986 = TryImplicitConversion(Initializer, Entity.getType(), 2987 SuppressUserConversions, 2988 AllowExplicitConversions, 2989 InOverloadResolution); 2990 if (ICS.isBad()) return true; 2991 2992 // Perform the actual conversion. 2993 Sequence.AddConversionSequenceStep(ICS, Entity.getType()); 2994 return false; 2995} 2996 2997InitializationSequence::InitializationSequence(Sema &S, 2998 const InitializedEntity &Entity, 2999 const InitializationKind &Kind, 3000 Expr **Args, 3001 unsigned NumArgs) 3002 : FailedCandidateSet(Kind.getLocation()) { 3003 ASTContext &Context = S.Context; 3004 3005 // C++0x [dcl.init]p16: 3006 // The semantics of initializers are as follows. The destination type is 3007 // the type of the object or reference being initialized and the source 3008 // type is the type of the initializer expression. The source type is not 3009 // defined when the initializer is a braced-init-list or when it is a 3010 // parenthesized list of expressions. 3011 QualType DestType = Entity.getType(); 3012 3013 if (DestType->isDependentType() || 3014 Expr::hasAnyTypeDependentArguments(Args, NumArgs)) { 3015 SequenceKind = DependentSequence; 3016 return; 3017 } 3018 3019 QualType SourceType; 3020 Expr *Initializer = 0; 3021 if (NumArgs == 1) { 3022 Initializer = Args[0]; 3023 if (!isa<InitListExpr>(Initializer)) 3024 SourceType = Initializer->getType(); 3025 } 3026 3027 // - If the initializer is a braced-init-list, the object is 3028 // list-initialized (8.5.4). 3029 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) { 3030 TryListInitialization(S, Entity, Kind, InitList, *this); 3031 return; 3032 } 3033 3034 // - If the destination type is a reference type, see 8.5.3. 3035 if (DestType->isReferenceType()) { 3036 // C++0x [dcl.init.ref]p1: 3037 // A variable declared to be a T& or T&&, that is, "reference to type T" 3038 // (8.3.2), shall be initialized by an object, or function, of type T or 3039 // by an object that can be converted into a T. 3040 // (Therefore, multiple arguments are not permitted.) 3041 if (NumArgs != 1) 3042 SetFailed(FK_TooManyInitsForReference); 3043 else 3044 TryReferenceInitialization(S, Entity, Kind, Args[0], *this); 3045 return; 3046 } 3047 3048 // - If the destination type is an array of characters, an array of 3049 // char16_t, an array of char32_t, or an array of wchar_t, and the 3050 // initializer is a string literal, see 8.5.2. 3051 if (Initializer && IsStringInit(Initializer, DestType, Context)) { 3052 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this); 3053 return; 3054 } 3055 3056 // - If the initializer is (), the object is value-initialized. 3057 if (Kind.getKind() == InitializationKind::IK_Value || 3058 (Kind.getKind() == InitializationKind::IK_Direct && NumArgs == 0)) { 3059 TryValueInitialization(S, Entity, Kind, *this); 3060 return; 3061 } 3062 3063 // Handle default initialization. 3064 if (Kind.getKind() == InitializationKind::IK_Default){ 3065 TryDefaultInitialization(S, Entity, Kind, *this); 3066 return; 3067 } 3068 3069 // - Otherwise, if the destination type is an array, the program is 3070 // ill-formed. 3071 if (const ArrayType *AT = Context.getAsArrayType(DestType)) { 3072 if (AT->getElementType()->isAnyCharacterType()) 3073 SetFailed(FK_ArrayNeedsInitListOrStringLiteral); 3074 else 3075 SetFailed(FK_ArrayNeedsInitList); 3076 3077 return; 3078 } 3079 3080 // Handle initialization in C 3081 if (!S.getLangOptions().CPlusPlus) { 3082 setSequenceKind(CAssignment); 3083 AddCAssignmentStep(DestType); 3084 return; 3085 } 3086 3087 // - If the destination type is a (possibly cv-qualified) class type: 3088 if (DestType->isRecordType()) { 3089 // - If the initialization is direct-initialization, or if it is 3090 // copy-initialization where the cv-unqualified version of the 3091 // source type is the same class as, or a derived class of, the 3092 // class of the destination, constructors are considered. [...] 3093 if (Kind.getKind() == InitializationKind::IK_Direct || 3094 (Kind.getKind() == InitializationKind::IK_Copy && 3095 (Context.hasSameUnqualifiedType(SourceType, DestType) || 3096 S.IsDerivedFrom(SourceType, DestType)))) 3097 TryConstructorInitialization(S, Entity, Kind, Args, NumArgs, 3098 Entity.getType(), *this); 3099 // - Otherwise (i.e., for the remaining copy-initialization cases), 3100 // user-defined conversion sequences that can convert from the source 3101 // type to the destination type or (when a conversion function is 3102 // used) to a derived class thereof are enumerated as described in 3103 // 13.3.1.4, and the best one is chosen through overload resolution 3104 // (13.3). 3105 else 3106 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 3107 return; 3108 } 3109 3110 if (NumArgs > 1) { 3111 SetFailed(FK_TooManyInitsForScalar); 3112 return; 3113 } 3114 assert(NumArgs == 1 && "Zero-argument case handled above"); 3115 3116 // - Otherwise, if the source type is a (possibly cv-qualified) class 3117 // type, conversion functions are considered. 3118 if (!SourceType.isNull() && SourceType->isRecordType()) { 3119 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 3120 return; 3121 } 3122 3123 // - Otherwise, the initial value of the object being initialized is the 3124 // (possibly converted) value of the initializer expression. Standard 3125 // conversions (Clause 4) will be used, if necessary, to convert the 3126 // initializer expression to the cv-unqualified version of the 3127 // destination type; no user-defined conversions are considered. 3128 if (S.TryImplicitConversion(*this, Entity, Initializer, 3129 /*SuppressUserConversions*/ true, 3130 /*AllowExplicitConversions*/ false, 3131 /*InOverloadResolution*/ false)) 3132 SetFailed(InitializationSequence::FK_ConversionFailed); 3133 else 3134 setSequenceKind(StandardConversion); 3135} 3136 3137InitializationSequence::~InitializationSequence() { 3138 for (llvm::SmallVectorImpl<Step>::iterator Step = Steps.begin(), 3139 StepEnd = Steps.end(); 3140 Step != StepEnd; ++Step) 3141 Step->Destroy(); 3142} 3143 3144//===----------------------------------------------------------------------===// 3145// Perform initialization 3146//===----------------------------------------------------------------------===// 3147static Sema::AssignmentAction 3148getAssignmentAction(const InitializedEntity &Entity) { 3149 switch(Entity.getKind()) { 3150 case InitializedEntity::EK_Variable: 3151 case InitializedEntity::EK_New: 3152 return Sema::AA_Initializing; 3153 3154 case InitializedEntity::EK_Parameter: 3155 if (Entity.getDecl() && 3156 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext())) 3157 return Sema::AA_Sending; 3158 3159 return Sema::AA_Passing; 3160 3161 case InitializedEntity::EK_Result: 3162 return Sema::AA_Returning; 3163 3164 case InitializedEntity::EK_Exception: 3165 case InitializedEntity::EK_Base: 3166 llvm_unreachable("No assignment action for C++-specific initialization"); 3167 break; 3168 3169 case InitializedEntity::EK_Temporary: 3170 // FIXME: Can we tell apart casting vs. converting? 3171 return Sema::AA_Casting; 3172 3173 case InitializedEntity::EK_Member: 3174 case InitializedEntity::EK_ArrayElement: 3175 case InitializedEntity::EK_VectorElement: 3176 case InitializedEntity::EK_BlockElement: 3177 return Sema::AA_Initializing; 3178 } 3179 3180 return Sema::AA_Converting; 3181} 3182 3183/// \brief Whether we should binding a created object as a temporary when 3184/// initializing the given entity. 3185static bool shouldBindAsTemporary(const InitializedEntity &Entity) { 3186 switch (Entity.getKind()) { 3187 case InitializedEntity::EK_ArrayElement: 3188 case InitializedEntity::EK_Member: 3189 case InitializedEntity::EK_Result: 3190 case InitializedEntity::EK_New: 3191 case InitializedEntity::EK_Variable: 3192 case InitializedEntity::EK_Base: 3193 case InitializedEntity::EK_VectorElement: 3194 case InitializedEntity::EK_Exception: 3195 case InitializedEntity::EK_BlockElement: 3196 return false; 3197 3198 case InitializedEntity::EK_Parameter: 3199 case InitializedEntity::EK_Temporary: 3200 return true; 3201 } 3202 3203 llvm_unreachable("missed an InitializedEntity kind?"); 3204} 3205 3206/// \brief Whether the given entity, when initialized with an object 3207/// created for that initialization, requires destruction. 3208static bool shouldDestroyTemporary(const InitializedEntity &Entity) { 3209 switch (Entity.getKind()) { 3210 case InitializedEntity::EK_Member: 3211 case InitializedEntity::EK_Result: 3212 case InitializedEntity::EK_New: 3213 case InitializedEntity::EK_Base: 3214 case InitializedEntity::EK_VectorElement: 3215 case InitializedEntity::EK_BlockElement: 3216 return false; 3217 3218 case InitializedEntity::EK_Variable: 3219 case InitializedEntity::EK_Parameter: 3220 case InitializedEntity::EK_Temporary: 3221 case InitializedEntity::EK_ArrayElement: 3222 case InitializedEntity::EK_Exception: 3223 return true; 3224 } 3225 3226 llvm_unreachable("missed an InitializedEntity kind?"); 3227} 3228 3229/// \brief Make a (potentially elidable) temporary copy of the object 3230/// provided by the given initializer by calling the appropriate copy 3231/// constructor. 3232/// 3233/// \param S The Sema object used for type-checking. 3234/// 3235/// \param T The type of the temporary object, which must either by 3236/// the type of the initializer expression or a superclass thereof. 3237/// 3238/// \param Enter The entity being initialized. 3239/// 3240/// \param CurInit The initializer expression. 3241/// 3242/// \param IsExtraneousCopy Whether this is an "extraneous" copy that 3243/// is permitted in C++03 (but not C++0x) when binding a reference to 3244/// an rvalue. 3245/// 3246/// \returns An expression that copies the initializer expression into 3247/// a temporary object, or an error expression if a copy could not be 3248/// created. 3249static Sema::OwningExprResult CopyObject(Sema &S, 3250 QualType T, 3251 const InitializedEntity &Entity, 3252 Sema::OwningExprResult CurInit, 3253 bool IsExtraneousCopy) { 3254 // Determine which class type we're copying to. 3255 Expr *CurInitExpr = (Expr *)CurInit.get(); 3256 CXXRecordDecl *Class = 0; 3257 if (const RecordType *Record = T->getAs<RecordType>()) 3258 Class = cast<CXXRecordDecl>(Record->getDecl()); 3259 if (!Class) 3260 return move(CurInit); 3261 3262 // C++0x [class.copy]p34: 3263 // When certain criteria are met, an implementation is allowed to 3264 // omit the copy/move construction of a class object, even if the 3265 // copy/move constructor and/or destructor for the object have 3266 // side effects. [...] 3267 // - when a temporary class object that has not been bound to a 3268 // reference (12.2) would be copied/moved to a class object 3269 // with the same cv-unqualified type, the copy/move operation 3270 // can be omitted by constructing the temporary object 3271 // directly into the target of the omitted copy/move 3272 // 3273 // Note that the other three bullets are handled elsewhere. Copy 3274 // elision for return statements and throw expressions are handled as part 3275 // of constructor initialization, while copy elision for exception handlers 3276 // is handled by the run-time. 3277 bool Elidable = CurInitExpr->isTemporaryObject() && 3278 S.Context.hasSameUnqualifiedType(T, CurInitExpr->getType()); 3279 SourceLocation Loc; 3280 switch (Entity.getKind()) { 3281 case InitializedEntity::EK_Result: 3282 Loc = Entity.getReturnLoc(); 3283 break; 3284 3285 case InitializedEntity::EK_Exception: 3286 Loc = Entity.getThrowLoc(); 3287 break; 3288 3289 case InitializedEntity::EK_Variable: 3290 Loc = Entity.getDecl()->getLocation(); 3291 break; 3292 3293 case InitializedEntity::EK_ArrayElement: 3294 case InitializedEntity::EK_Member: 3295 case InitializedEntity::EK_Parameter: 3296 case InitializedEntity::EK_Temporary: 3297 case InitializedEntity::EK_New: 3298 case InitializedEntity::EK_Base: 3299 case InitializedEntity::EK_VectorElement: 3300 case InitializedEntity::EK_BlockElement: 3301 Loc = CurInitExpr->getLocStart(); 3302 break; 3303 } 3304 3305 // Make sure that the type we are copying is complete. 3306 if (S.RequireCompleteType(Loc, T, S.PDiag(diag::err_temp_copy_incomplete))) 3307 return move(CurInit); 3308 3309 // Perform overload resolution using the class's copy constructors. 3310 DeclarationName ConstructorName 3311 = S.Context.DeclarationNames.getCXXConstructorName( 3312 S.Context.getCanonicalType(S.Context.getTypeDeclType(Class))); 3313 DeclContext::lookup_iterator Con, ConEnd; 3314 OverloadCandidateSet CandidateSet(Loc); 3315 for (llvm::tie(Con, ConEnd) = Class->lookup(ConstructorName); 3316 Con != ConEnd; ++Con) { 3317 // Only consider copy constructors. 3318 CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(*Con); 3319 if (!Constructor || Constructor->isInvalidDecl() || 3320 !Constructor->isCopyConstructor() || 3321 !Constructor->isConvertingConstructor(/*AllowExplicit=*/false)) 3322 continue; 3323 3324 DeclAccessPair FoundDecl 3325 = DeclAccessPair::make(Constructor, Constructor->getAccess()); 3326 S.AddOverloadCandidate(Constructor, FoundDecl, 3327 &CurInitExpr, 1, CandidateSet); 3328 } 3329 3330 OverloadCandidateSet::iterator Best; 3331 switch (S.BestViableFunction(CandidateSet, Loc, Best)) { 3332 case OR_Success: 3333 break; 3334 3335 case OR_No_Viable_Function: 3336 S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext() 3337 ? diag::ext_rvalue_to_reference_temp_copy_no_viable 3338 : diag::err_temp_copy_no_viable) 3339 << (int)Entity.getKind() << CurInitExpr->getType() 3340 << CurInitExpr->getSourceRange(); 3341 S.PrintOverloadCandidates(CandidateSet, Sema::OCD_AllCandidates, 3342 &CurInitExpr, 1); 3343 if (!IsExtraneousCopy || S.isSFINAEContext()) 3344 return S.ExprError(); 3345 return move(CurInit); 3346 3347 case OR_Ambiguous: 3348 S.Diag(Loc, diag::err_temp_copy_ambiguous) 3349 << (int)Entity.getKind() << CurInitExpr->getType() 3350 << CurInitExpr->getSourceRange(); 3351 S.PrintOverloadCandidates(CandidateSet, Sema::OCD_ViableCandidates, 3352 &CurInitExpr, 1); 3353 return S.ExprError(); 3354 3355 case OR_Deleted: 3356 S.Diag(Loc, diag::err_temp_copy_deleted) 3357 << (int)Entity.getKind() << CurInitExpr->getType() 3358 << CurInitExpr->getSourceRange(); 3359 S.Diag(Best->Function->getLocation(), diag::note_unavailable_here) 3360 << Best->Function->isDeleted(); 3361 return S.ExprError(); 3362 } 3363 3364 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function); 3365 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(S); 3366 CurInit.release(); // Ownership transferred into MultiExprArg, below. 3367 3368 S.CheckConstructorAccess(Loc, Constructor, Entity, 3369 Best->FoundDecl.getAccess(), IsExtraneousCopy); 3370 3371 if (IsExtraneousCopy) { 3372 // If this is a totally extraneous copy for C++03 reference 3373 // binding purposes, just return the original initialization 3374 // expression. We don't generate an (elided) copy operation here 3375 // because doing so would require us to pass down a flag to avoid 3376 // infinite recursion, where each step adds another extraneous, 3377 // elidable copy. 3378 3379 // Instantiate the default arguments of any extra parameters in 3380 // the selected copy constructor, as if we were going to create a 3381 // proper call to the copy constructor. 3382 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) { 3383 ParmVarDecl *Parm = Constructor->getParamDecl(I); 3384 if (S.RequireCompleteType(Loc, Parm->getType(), 3385 S.PDiag(diag::err_call_incomplete_argument))) 3386 break; 3387 3388 // Build the default argument expression; we don't actually care 3389 // if this succeeds or not, because this routine will complain 3390 // if there was a problem. 3391 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm); 3392 } 3393 3394 return S.Owned(CurInitExpr); 3395 } 3396 3397 // Determine the arguments required to actually perform the 3398 // constructor call (we might have derived-to-base conversions, or 3399 // the copy constructor may have default arguments). 3400 if (S.CompleteConstructorCall(Constructor, 3401 Sema::MultiExprArg(S, 3402 (void **)&CurInitExpr, 3403 1), 3404 Loc, ConstructorArgs)) 3405 return S.ExprError(); 3406 3407 // Actually perform the constructor call. 3408 CurInit = S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable, 3409 move_arg(ConstructorArgs)); 3410 3411 // If we're supposed to bind temporaries, do so. 3412 if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity)) 3413 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 3414 return move(CurInit); 3415} 3416 3417void InitializationSequence::PrintInitLocationNote(Sema &S, 3418 const InitializedEntity &Entity) { 3419 if (Entity.getKind() == InitializedEntity::EK_Parameter && Entity.getDecl()) { 3420 if (Entity.getDecl()->getLocation().isInvalid()) 3421 return; 3422 3423 if (Entity.getDecl()->getDeclName()) 3424 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here) 3425 << Entity.getDecl()->getDeclName(); 3426 else 3427 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here); 3428 } 3429} 3430 3431Action::OwningExprResult 3432InitializationSequence::Perform(Sema &S, 3433 const InitializedEntity &Entity, 3434 const InitializationKind &Kind, 3435 Action::MultiExprArg Args, 3436 QualType *ResultType) { 3437 if (SequenceKind == FailedSequence) { 3438 unsigned NumArgs = Args.size(); 3439 Diagnose(S, Entity, Kind, (Expr **)Args.release(), NumArgs); 3440 return S.ExprError(); 3441 } 3442 3443 if (SequenceKind == DependentSequence) { 3444 // If the declaration is a non-dependent, incomplete array type 3445 // that has an initializer, then its type will be completed once 3446 // the initializer is instantiated. 3447 if (ResultType && !Entity.getType()->isDependentType() && 3448 Args.size() == 1) { 3449 QualType DeclType = Entity.getType(); 3450 if (const IncompleteArrayType *ArrayT 3451 = S.Context.getAsIncompleteArrayType(DeclType)) { 3452 // FIXME: We don't currently have the ability to accurately 3453 // compute the length of an initializer list without 3454 // performing full type-checking of the initializer list 3455 // (since we have to determine where braces are implicitly 3456 // introduced and such). So, we fall back to making the array 3457 // type a dependently-sized array type with no specified 3458 // bound. 3459 if (isa<InitListExpr>((Expr *)Args.get()[0])) { 3460 SourceRange Brackets; 3461 3462 // Scavange the location of the brackets from the entity, if we can. 3463 if (DeclaratorDecl *DD = Entity.getDecl()) { 3464 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) { 3465 TypeLoc TL = TInfo->getTypeLoc(); 3466 if (IncompleteArrayTypeLoc *ArrayLoc 3467 = dyn_cast<IncompleteArrayTypeLoc>(&TL)) 3468 Brackets = ArrayLoc->getBracketsRange(); 3469 } 3470 } 3471 3472 *ResultType 3473 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(), 3474 /*NumElts=*/0, 3475 ArrayT->getSizeModifier(), 3476 ArrayT->getIndexTypeCVRQualifiers(), 3477 Brackets); 3478 } 3479 3480 } 3481 } 3482 3483 if (Kind.getKind() == InitializationKind::IK_Copy || Kind.isExplicitCast()) 3484 return Sema::OwningExprResult(S, Args.release()[0]); 3485 3486 if (Args.size() == 0) 3487 return S.Owned((Expr *)0); 3488 3489 unsigned NumArgs = Args.size(); 3490 return S.Owned(new (S.Context) ParenListExpr(S.Context, 3491 SourceLocation(), 3492 (Expr **)Args.release(), 3493 NumArgs, 3494 SourceLocation())); 3495 } 3496 3497 if (SequenceKind == NoInitialization) 3498 return S.Owned((Expr *)0); 3499 3500 QualType DestType = Entity.getType().getNonReferenceType(); 3501 // FIXME: Ugly hack around the fact that Entity.getType() is not 3502 // the same as Entity.getDecl()->getType() in cases involving type merging, 3503 // and we want latter when it makes sense. 3504 if (ResultType) 3505 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() : 3506 Entity.getType(); 3507 3508 Sema::OwningExprResult CurInit = S.Owned((Expr *)0); 3509 3510 assert(!Steps.empty() && "Cannot have an empty initialization sequence"); 3511 3512 // For initialization steps that start with a single initializer, 3513 // grab the only argument out the Args and place it into the "current" 3514 // initializer. 3515 switch (Steps.front().Kind) { 3516 case SK_ResolveAddressOfOverloadedFunction: 3517 case SK_CastDerivedToBaseRValue: 3518 case SK_CastDerivedToBaseLValue: 3519 case SK_BindReference: 3520 case SK_BindReferenceToTemporary: 3521 case SK_ExtraneousCopyToTemporary: 3522 case SK_UserConversion: 3523 case SK_QualificationConversionLValue: 3524 case SK_QualificationConversionRValue: 3525 case SK_ConversionSequence: 3526 case SK_ListInitialization: 3527 case SK_CAssignment: 3528 case SK_StringInit: 3529 assert(Args.size() == 1); 3530 CurInit = Sema::OwningExprResult(S, ((Expr **)(Args.get()))[0]->Retain()); 3531 if (CurInit.isInvalid()) 3532 return S.ExprError(); 3533 break; 3534 3535 case SK_ConstructorInitialization: 3536 case SK_ZeroInitialization: 3537 break; 3538 } 3539 3540 // Walk through the computed steps for the initialization sequence, 3541 // performing the specified conversions along the way. 3542 bool ConstructorInitRequiresZeroInit = false; 3543 for (step_iterator Step = step_begin(), StepEnd = step_end(); 3544 Step != StepEnd; ++Step) { 3545 if (CurInit.isInvalid()) 3546 return S.ExprError(); 3547 3548 Expr *CurInitExpr = (Expr *)CurInit.get(); 3549 QualType SourceType = CurInitExpr? CurInitExpr->getType() : QualType(); 3550 3551 switch (Step->Kind) { 3552 case SK_ResolveAddressOfOverloadedFunction: 3553 // Overload resolution determined which function invoke; update the 3554 // initializer to reflect that choice. 3555 S.CheckAddressOfMemberAccess(CurInitExpr, Step->Function.FoundDecl); 3556 S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()); 3557 CurInit = S.FixOverloadedFunctionReference(move(CurInit), 3558 Step->Function.FoundDecl, 3559 Step->Function.Function); 3560 break; 3561 3562 case SK_CastDerivedToBaseRValue: 3563 case SK_CastDerivedToBaseLValue: { 3564 // We have a derived-to-base cast that produces either an rvalue or an 3565 // lvalue. Perform that cast. 3566 3567 CXXBaseSpecifierArray BasePath; 3568 3569 // Casts to inaccessible base classes are allowed with C-style casts. 3570 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); 3571 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type, 3572 CurInitExpr->getLocStart(), 3573 CurInitExpr->getSourceRange(), 3574 &BasePath, IgnoreBaseAccess)) 3575 return S.ExprError(); 3576 3577 if (S.BasePathInvolvesVirtualBase(BasePath)) { 3578 QualType T = SourceType; 3579 if (const PointerType *Pointer = T->getAs<PointerType>()) 3580 T = Pointer->getPointeeType(); 3581 if (const RecordType *RecordTy = T->getAs<RecordType>()) 3582 S.MarkVTableUsed(CurInitExpr->getLocStart(), 3583 cast<CXXRecordDecl>(RecordTy->getDecl())); 3584 } 3585 3586 CurInit = S.Owned(new (S.Context) ImplicitCastExpr(Step->Type, 3587 CastExpr::CK_DerivedToBase, 3588 (Expr*)CurInit.release(), 3589 BasePath, 3590 Step->Kind == SK_CastDerivedToBaseLValue)); 3591 break; 3592 } 3593 3594 case SK_BindReference: 3595 if (FieldDecl *BitField = CurInitExpr->getBitField()) { 3596 // References cannot bind to bit fields (C++ [dcl.init.ref]p5). 3597 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield) 3598 << Entity.getType().isVolatileQualified() 3599 << BitField->getDeclName() 3600 << CurInitExpr->getSourceRange(); 3601 S.Diag(BitField->getLocation(), diag::note_bitfield_decl); 3602 return S.ExprError(); 3603 } 3604 3605 if (CurInitExpr->refersToVectorElement()) { 3606 // References cannot bind to vector elements. 3607 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element) 3608 << Entity.getType().isVolatileQualified() 3609 << CurInitExpr->getSourceRange(); 3610 PrintInitLocationNote(S, Entity); 3611 return S.ExprError(); 3612 } 3613 3614 // Reference binding does not have any corresponding ASTs. 3615 3616 // Check exception specifications 3617 if (S.CheckExceptionSpecCompatibility(CurInitExpr, DestType)) 3618 return S.ExprError(); 3619 3620 break; 3621 3622 case SK_BindReferenceToTemporary: 3623 // Reference binding does not have any corresponding ASTs. 3624 3625 // Check exception specifications 3626 if (S.CheckExceptionSpecCompatibility(CurInitExpr, DestType)) 3627 return S.ExprError(); 3628 3629 break; 3630 3631 case SK_ExtraneousCopyToTemporary: 3632 CurInit = CopyObject(S, Step->Type, Entity, move(CurInit), 3633 /*IsExtraneousCopy=*/true); 3634 break; 3635 3636 case SK_UserConversion: { 3637 // We have a user-defined conversion that invokes either a constructor 3638 // or a conversion function. 3639 CastExpr::CastKind CastKind = CastExpr::CK_Unknown; 3640 bool IsCopy = false; 3641 FunctionDecl *Fn = Step->Function.Function; 3642 DeclAccessPair FoundFn = Step->Function.FoundDecl; 3643 bool CreatedObject = false; 3644 bool IsLvalue = false; 3645 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) { 3646 // Build a call to the selected constructor. 3647 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(S); 3648 SourceLocation Loc = CurInitExpr->getLocStart(); 3649 CurInit.release(); // Ownership transferred into MultiExprArg, below. 3650 3651 // Determine the arguments required to actually perform the constructor 3652 // call. 3653 if (S.CompleteConstructorCall(Constructor, 3654 Sema::MultiExprArg(S, 3655 (void **)&CurInitExpr, 3656 1), 3657 Loc, ConstructorArgs)) 3658 return S.ExprError(); 3659 3660 // Build the an expression that constructs a temporary. 3661 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor, 3662 move_arg(ConstructorArgs)); 3663 if (CurInit.isInvalid()) 3664 return S.ExprError(); 3665 3666 S.CheckConstructorAccess(Kind.getLocation(), Constructor, Entity, 3667 FoundFn.getAccess()); 3668 S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()); 3669 3670 CastKind = CastExpr::CK_ConstructorConversion; 3671 QualType Class = S.Context.getTypeDeclType(Constructor->getParent()); 3672 if (S.Context.hasSameUnqualifiedType(SourceType, Class) || 3673 S.IsDerivedFrom(SourceType, Class)) 3674 IsCopy = true; 3675 3676 CreatedObject = true; 3677 } else { 3678 // Build a call to the conversion function. 3679 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn); 3680 IsLvalue = Conversion->getResultType()->isLValueReferenceType(); 3681 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInitExpr, 0, 3682 FoundFn); 3683 S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()); 3684 3685 // FIXME: Should we move this initialization into a separate 3686 // derived-to-base conversion? I believe the answer is "no", because 3687 // we don't want to turn off access control here for c-style casts. 3688 if (S.PerformObjectArgumentInitialization(CurInitExpr, /*Qualifier=*/0, 3689 FoundFn, Conversion)) 3690 return S.ExprError(); 3691 3692 // Do a little dance to make sure that CurInit has the proper 3693 // pointer. 3694 CurInit.release(); 3695 3696 // Build the actual call to the conversion function. 3697 CurInit = S.Owned(S.BuildCXXMemberCallExpr(CurInitExpr, FoundFn, 3698 Conversion)); 3699 if (CurInit.isInvalid() || !CurInit.get()) 3700 return S.ExprError(); 3701 3702 CastKind = CastExpr::CK_UserDefinedConversion; 3703 3704 CreatedObject = Conversion->getResultType()->isRecordType(); 3705 } 3706 3707 bool RequiresCopy = !IsCopy && 3708 getKind() != InitializationSequence::ReferenceBinding; 3709 if (RequiresCopy || shouldBindAsTemporary(Entity)) 3710 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 3711 else if (CreatedObject && shouldDestroyTemporary(Entity)) { 3712 CurInitExpr = static_cast<Expr *>(CurInit.get()); 3713 QualType T = CurInitExpr->getType(); 3714 if (const RecordType *Record = T->getAs<RecordType>()) { 3715 CXXDestructorDecl *Destructor 3716 = cast<CXXRecordDecl>(Record->getDecl())->getDestructor(S.Context); 3717 S.CheckDestructorAccess(CurInitExpr->getLocStart(), Destructor, 3718 S.PDiag(diag::err_access_dtor_temp) << T); 3719 S.MarkDeclarationReferenced(CurInitExpr->getLocStart(), Destructor); 3720 } 3721 } 3722 3723 CurInitExpr = CurInit.takeAs<Expr>(); 3724 CurInit = S.Owned(new (S.Context) ImplicitCastExpr(CurInitExpr->getType(), 3725 CastKind, 3726 CurInitExpr, 3727 CXXBaseSpecifierArray(), 3728 IsLvalue)); 3729 3730 if (RequiresCopy) 3731 CurInit = CopyObject(S, Entity.getType().getNonReferenceType(), Entity, 3732 move(CurInit), /*IsExtraneousCopy=*/false); 3733 3734 break; 3735 } 3736 3737 case SK_QualificationConversionLValue: 3738 case SK_QualificationConversionRValue: 3739 // Perform a qualification conversion; these can never go wrong. 3740 S.ImpCastExprToType(CurInitExpr, Step->Type, 3741 CastExpr::CK_NoOp, 3742 Step->Kind == SK_QualificationConversionLValue); 3743 CurInit.release(); 3744 CurInit = S.Owned(CurInitExpr); 3745 break; 3746 3747 case SK_ConversionSequence: { 3748 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); 3749 3750 if (S.PerformImplicitConversion(CurInitExpr, Step->Type, *Step->ICS, 3751 Sema::AA_Converting, IgnoreBaseAccess)) 3752 return S.ExprError(); 3753 3754 CurInit.release(); 3755 CurInit = S.Owned(CurInitExpr); 3756 break; 3757 } 3758 3759 case SK_ListInitialization: { 3760 InitListExpr *InitList = cast<InitListExpr>(CurInitExpr); 3761 QualType Ty = Step->Type; 3762 if (S.CheckInitList(Entity, InitList, ResultType? *ResultType : Ty)) 3763 return S.ExprError(); 3764 3765 CurInit.release(); 3766 CurInit = S.Owned(InitList); 3767 break; 3768 } 3769 3770 case SK_ConstructorInitialization: { 3771 unsigned NumArgs = Args.size(); 3772 CXXConstructorDecl *Constructor 3773 = cast<CXXConstructorDecl>(Step->Function.Function); 3774 3775 // Build a call to the selected constructor. 3776 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(S); 3777 SourceLocation Loc = Kind.getLocation(); 3778 3779 // Determine the arguments required to actually perform the constructor 3780 // call. 3781 if (S.CompleteConstructorCall(Constructor, move(Args), 3782 Loc, ConstructorArgs)) 3783 return S.ExprError(); 3784 3785 // Build the expression that constructs a temporary. 3786 if (Entity.getKind() == InitializedEntity::EK_Temporary && 3787 NumArgs != 1 && // FIXME: Hack to work around cast weirdness 3788 (Kind.getKind() == InitializationKind::IK_Direct || 3789 Kind.getKind() == InitializationKind::IK_Value)) { 3790 // An explicitly-constructed temporary, e.g., X(1, 2). 3791 unsigned NumExprs = ConstructorArgs.size(); 3792 Expr **Exprs = (Expr **)ConstructorArgs.take(); 3793 S.MarkDeclarationReferenced(Kind.getLocation(), Constructor); 3794 CurInit = S.Owned(new (S.Context) CXXTemporaryObjectExpr(S.Context, 3795 Constructor, 3796 Entity.getType(), 3797 Kind.getLocation(), 3798 Exprs, 3799 NumExprs, 3800 Kind.getParenRange().getEnd(), 3801 ConstructorInitRequiresZeroInit)); 3802 } else { 3803 CXXConstructExpr::ConstructionKind ConstructKind = 3804 CXXConstructExpr::CK_Complete; 3805 3806 if (Entity.getKind() == InitializedEntity::EK_Base) { 3807 ConstructKind = Entity.getBaseSpecifier()->isVirtual() ? 3808 CXXConstructExpr::CK_VirtualBase : 3809 CXXConstructExpr::CK_NonVirtualBase; 3810 } 3811 3812 // If the entity allows NRVO, mark the construction as elidable 3813 // unconditionally. 3814 if (Entity.allowsNRVO()) 3815 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 3816 Constructor, /*Elidable=*/true, 3817 move_arg(ConstructorArgs), 3818 ConstructorInitRequiresZeroInit, 3819 ConstructKind); 3820 else 3821 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 3822 Constructor, 3823 move_arg(ConstructorArgs), 3824 ConstructorInitRequiresZeroInit, 3825 ConstructKind); 3826 } 3827 if (CurInit.isInvalid()) 3828 return S.ExprError(); 3829 3830 // Only check access if all of that succeeded. 3831 S.CheckConstructorAccess(Loc, Constructor, Entity, 3832 Step->Function.FoundDecl.getAccess()); 3833 S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Loc); 3834 3835 if (shouldBindAsTemporary(Entity)) 3836 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 3837 3838 break; 3839 } 3840 3841 case SK_ZeroInitialization: { 3842 step_iterator NextStep = Step; 3843 ++NextStep; 3844 if (NextStep != StepEnd && 3845 NextStep->Kind == SK_ConstructorInitialization) { 3846 // The need for zero-initialization is recorded directly into 3847 // the call to the object's constructor within the next step. 3848 ConstructorInitRequiresZeroInit = true; 3849 } else if (Kind.getKind() == InitializationKind::IK_Value && 3850 S.getLangOptions().CPlusPlus && 3851 !Kind.isImplicitValueInit()) { 3852 CurInit = S.Owned(new (S.Context) CXXZeroInitValueExpr(Step->Type, 3853 Kind.getRange().getBegin(), 3854 Kind.getRange().getEnd())); 3855 } else { 3856 CurInit = S.Owned(new (S.Context) ImplicitValueInitExpr(Step->Type)); 3857 } 3858 break; 3859 } 3860 3861 case SK_CAssignment: { 3862 QualType SourceType = CurInitExpr->getType(); 3863 Sema::AssignConvertType ConvTy = 3864 S.CheckSingleAssignmentConstraints(Step->Type, CurInitExpr); 3865 3866 // If this is a call, allow conversion to a transparent union. 3867 if (ConvTy != Sema::Compatible && 3868 Entity.getKind() == InitializedEntity::EK_Parameter && 3869 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExpr) 3870 == Sema::Compatible) 3871 ConvTy = Sema::Compatible; 3872 3873 bool Complained; 3874 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(), 3875 Step->Type, SourceType, 3876 CurInitExpr, 3877 getAssignmentAction(Entity), 3878 &Complained)) { 3879 PrintInitLocationNote(S, Entity); 3880 return S.ExprError(); 3881 } else if (Complained) 3882 PrintInitLocationNote(S, Entity); 3883 3884 CurInit.release(); 3885 CurInit = S.Owned(CurInitExpr); 3886 break; 3887 } 3888 3889 case SK_StringInit: { 3890 QualType Ty = Step->Type; 3891 CheckStringInit(CurInitExpr, ResultType ? *ResultType : Ty, S); 3892 break; 3893 } 3894 } 3895 } 3896 3897 return move(CurInit); 3898} 3899 3900//===----------------------------------------------------------------------===// 3901// Diagnose initialization failures 3902//===----------------------------------------------------------------------===// 3903bool InitializationSequence::Diagnose(Sema &S, 3904 const InitializedEntity &Entity, 3905 const InitializationKind &Kind, 3906 Expr **Args, unsigned NumArgs) { 3907 if (SequenceKind != FailedSequence) 3908 return false; 3909 3910 QualType DestType = Entity.getType(); 3911 switch (Failure) { 3912 case FK_TooManyInitsForReference: 3913 // FIXME: Customize for the initialized entity? 3914 if (NumArgs == 0) 3915 S.Diag(Kind.getLocation(), diag::err_reference_without_init) 3916 << DestType.getNonReferenceType(); 3917 else // FIXME: diagnostic below could be better! 3918 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits) 3919 << SourceRange(Args[0]->getLocStart(), Args[NumArgs - 1]->getLocEnd()); 3920 break; 3921 3922 case FK_ArrayNeedsInitList: 3923 case FK_ArrayNeedsInitListOrStringLiteral: 3924 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) 3925 << (Failure == FK_ArrayNeedsInitListOrStringLiteral); 3926 break; 3927 3928 case FK_AddressOfOverloadFailed: { 3929 DeclAccessPair Found; 3930 S.ResolveAddressOfOverloadedFunction(Args[0], 3931 DestType.getNonReferenceType(), 3932 true, 3933 Found); 3934 break; 3935 } 3936 3937 case FK_ReferenceInitOverloadFailed: 3938 case FK_UserConversionOverloadFailed: 3939 switch (FailedOverloadResult) { 3940 case OR_Ambiguous: 3941 if (Failure == FK_UserConversionOverloadFailed) 3942 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition) 3943 << Args[0]->getType() << DestType 3944 << Args[0]->getSourceRange(); 3945 else 3946 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous) 3947 << DestType << Args[0]->getType() 3948 << Args[0]->getSourceRange(); 3949 3950 S.PrintOverloadCandidates(FailedCandidateSet, Sema::OCD_ViableCandidates, 3951 Args, NumArgs); 3952 break; 3953 3954 case OR_No_Viable_Function: 3955 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition) 3956 << Args[0]->getType() << DestType.getNonReferenceType() 3957 << Args[0]->getSourceRange(); 3958 S.PrintOverloadCandidates(FailedCandidateSet, Sema::OCD_AllCandidates, 3959 Args, NumArgs); 3960 break; 3961 3962 case OR_Deleted: { 3963 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function) 3964 << Args[0]->getType() << DestType.getNonReferenceType() 3965 << Args[0]->getSourceRange(); 3966 OverloadCandidateSet::iterator Best; 3967 OverloadingResult Ovl = S.BestViableFunction(FailedCandidateSet, 3968 Kind.getLocation(), 3969 Best); 3970 if (Ovl == OR_Deleted) { 3971 S.Diag(Best->Function->getLocation(), diag::note_unavailable_here) 3972 << Best->Function->isDeleted(); 3973 } else { 3974 llvm_unreachable("Inconsistent overload resolution?"); 3975 } 3976 break; 3977 } 3978 3979 case OR_Success: 3980 llvm_unreachable("Conversion did not fail!"); 3981 break; 3982 } 3983 break; 3984 3985 case FK_NonConstLValueReferenceBindingToTemporary: 3986 case FK_NonConstLValueReferenceBindingToUnrelated: 3987 S.Diag(Kind.getLocation(), 3988 Failure == FK_NonConstLValueReferenceBindingToTemporary 3989 ? diag::err_lvalue_reference_bind_to_temporary 3990 : diag::err_lvalue_reference_bind_to_unrelated) 3991 << DestType.getNonReferenceType().isVolatileQualified() 3992 << DestType.getNonReferenceType() 3993 << Args[0]->getType() 3994 << Args[0]->getSourceRange(); 3995 break; 3996 3997 case FK_RValueReferenceBindingToLValue: 3998 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref) 3999 << Args[0]->getSourceRange(); 4000 break; 4001 4002 case FK_ReferenceInitDropsQualifiers: 4003 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals) 4004 << DestType.getNonReferenceType() 4005 << Args[0]->getType() 4006 << Args[0]->getSourceRange(); 4007 break; 4008 4009 case FK_ReferenceInitFailed: 4010 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed) 4011 << DestType.getNonReferenceType() 4012 << (Args[0]->isLvalue(S.Context) == Expr::LV_Valid) 4013 << Args[0]->getType() 4014 << Args[0]->getSourceRange(); 4015 break; 4016 4017 case FK_ConversionFailed: 4018 S.Diag(Kind.getLocation(), diag::err_init_conversion_failed) 4019 << (int)Entity.getKind() 4020 << DestType 4021 << (Args[0]->isLvalue(S.Context) == Expr::LV_Valid) 4022 << Args[0]->getType() 4023 << Args[0]->getSourceRange(); 4024 break; 4025 4026 case FK_TooManyInitsForScalar: { 4027 SourceRange R; 4028 4029 if (InitListExpr *InitList = dyn_cast<InitListExpr>(Args[0])) 4030 R = SourceRange(InitList->getInit(1)->getLocStart(), 4031 InitList->getLocEnd()); 4032 else 4033 R = SourceRange(Args[0]->getLocStart(), Args[NumArgs - 1]->getLocEnd()); 4034 4035 S.Diag(Kind.getLocation(), diag::err_excess_initializers) 4036 << /*scalar=*/2 << R; 4037 break; 4038 } 4039 4040 case FK_ReferenceBindingToInitList: 4041 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list) 4042 << DestType.getNonReferenceType() << Args[0]->getSourceRange(); 4043 break; 4044 4045 case FK_InitListBadDestinationType: 4046 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type) 4047 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange(); 4048 break; 4049 4050 case FK_ConstructorOverloadFailed: { 4051 SourceRange ArgsRange; 4052 if (NumArgs) 4053 ArgsRange = SourceRange(Args[0]->getLocStart(), 4054 Args[NumArgs - 1]->getLocEnd()); 4055 4056 // FIXME: Using "DestType" for the entity we're printing is probably 4057 // bad. 4058 switch (FailedOverloadResult) { 4059 case OR_Ambiguous: 4060 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init) 4061 << DestType << ArgsRange; 4062 S.PrintOverloadCandidates(FailedCandidateSet, 4063 Sema::OCD_ViableCandidates, Args, NumArgs); 4064 break; 4065 4066 case OR_No_Viable_Function: 4067 if (Kind.getKind() == InitializationKind::IK_Default && 4068 (Entity.getKind() == InitializedEntity::EK_Base || 4069 Entity.getKind() == InitializedEntity::EK_Member) && 4070 isa<CXXConstructorDecl>(S.CurContext)) { 4071 // This is implicit default initialization of a member or 4072 // base within a constructor. If no viable function was 4073 // found, notify the user that she needs to explicitly 4074 // initialize this base/member. 4075 CXXConstructorDecl *Constructor 4076 = cast<CXXConstructorDecl>(S.CurContext); 4077 if (Entity.getKind() == InitializedEntity::EK_Base) { 4078 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 4079 << Constructor->isImplicit() 4080 << S.Context.getTypeDeclType(Constructor->getParent()) 4081 << /*base=*/0 4082 << Entity.getType(); 4083 4084 RecordDecl *BaseDecl 4085 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>() 4086 ->getDecl(); 4087 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl) 4088 << S.Context.getTagDeclType(BaseDecl); 4089 } else { 4090 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 4091 << Constructor->isImplicit() 4092 << S.Context.getTypeDeclType(Constructor->getParent()) 4093 << /*member=*/1 4094 << Entity.getName(); 4095 S.Diag(Entity.getDecl()->getLocation(), diag::note_field_decl); 4096 4097 if (const RecordType *Record 4098 = Entity.getType()->getAs<RecordType>()) 4099 S.Diag(Record->getDecl()->getLocation(), 4100 diag::note_previous_decl) 4101 << S.Context.getTagDeclType(Record->getDecl()); 4102 } 4103 break; 4104 } 4105 4106 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init) 4107 << DestType << ArgsRange; 4108 S.PrintOverloadCandidates(FailedCandidateSet, Sema::OCD_AllCandidates, 4109 Args, NumArgs); 4110 break; 4111 4112 case OR_Deleted: { 4113 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) 4114 << true << DestType << ArgsRange; 4115 OverloadCandidateSet::iterator Best; 4116 OverloadingResult Ovl = S.BestViableFunction(FailedCandidateSet, 4117 Kind.getLocation(), 4118 Best); 4119 if (Ovl == OR_Deleted) { 4120 S.Diag(Best->Function->getLocation(), diag::note_unavailable_here) 4121 << Best->Function->isDeleted(); 4122 } else { 4123 llvm_unreachable("Inconsistent overload resolution?"); 4124 } 4125 break; 4126 } 4127 4128 case OR_Success: 4129 llvm_unreachable("Conversion did not fail!"); 4130 break; 4131 } 4132 break; 4133 } 4134 4135 case FK_DefaultInitOfConst: 4136 if (Entity.getKind() == InitializedEntity::EK_Member && 4137 isa<CXXConstructorDecl>(S.CurContext)) { 4138 // This is implicit default-initialization of a const member in 4139 // a constructor. Complain that it needs to be explicitly 4140 // initialized. 4141 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext); 4142 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor) 4143 << Constructor->isImplicit() 4144 << S.Context.getTypeDeclType(Constructor->getParent()) 4145 << /*const=*/1 4146 << Entity.getName(); 4147 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl) 4148 << Entity.getName(); 4149 } else { 4150 S.Diag(Kind.getLocation(), diag::err_default_init_const) 4151 << DestType << (bool)DestType->getAs<RecordType>(); 4152 } 4153 break; 4154 4155 case FK_Incomplete: 4156 S.RequireCompleteType(Kind.getLocation(), DestType, 4157 diag::err_init_incomplete_type); 4158 break; 4159 } 4160 4161 PrintInitLocationNote(S, Entity); 4162 return true; 4163} 4164 4165void InitializationSequence::dump(llvm::raw_ostream &OS) const { 4166 switch (SequenceKind) { 4167 case FailedSequence: { 4168 OS << "Failed sequence: "; 4169 switch (Failure) { 4170 case FK_TooManyInitsForReference: 4171 OS << "too many initializers for reference"; 4172 break; 4173 4174 case FK_ArrayNeedsInitList: 4175 OS << "array requires initializer list"; 4176 break; 4177 4178 case FK_ArrayNeedsInitListOrStringLiteral: 4179 OS << "array requires initializer list or string literal"; 4180 break; 4181 4182 case FK_AddressOfOverloadFailed: 4183 OS << "address of overloaded function failed"; 4184 break; 4185 4186 case FK_ReferenceInitOverloadFailed: 4187 OS << "overload resolution for reference initialization failed"; 4188 break; 4189 4190 case FK_NonConstLValueReferenceBindingToTemporary: 4191 OS << "non-const lvalue reference bound to temporary"; 4192 break; 4193 4194 case FK_NonConstLValueReferenceBindingToUnrelated: 4195 OS << "non-const lvalue reference bound to unrelated type"; 4196 break; 4197 4198 case FK_RValueReferenceBindingToLValue: 4199 OS << "rvalue reference bound to an lvalue"; 4200 break; 4201 4202 case FK_ReferenceInitDropsQualifiers: 4203 OS << "reference initialization drops qualifiers"; 4204 break; 4205 4206 case FK_ReferenceInitFailed: 4207 OS << "reference initialization failed"; 4208 break; 4209 4210 case FK_ConversionFailed: 4211 OS << "conversion failed"; 4212 break; 4213 4214 case FK_TooManyInitsForScalar: 4215 OS << "too many initializers for scalar"; 4216 break; 4217 4218 case FK_ReferenceBindingToInitList: 4219 OS << "referencing binding to initializer list"; 4220 break; 4221 4222 case FK_InitListBadDestinationType: 4223 OS << "initializer list for non-aggregate, non-scalar type"; 4224 break; 4225 4226 case FK_UserConversionOverloadFailed: 4227 OS << "overloading failed for user-defined conversion"; 4228 break; 4229 4230 case FK_ConstructorOverloadFailed: 4231 OS << "constructor overloading failed"; 4232 break; 4233 4234 case FK_DefaultInitOfConst: 4235 OS << "default initialization of a const variable"; 4236 break; 4237 4238 case FK_Incomplete: 4239 OS << "initialization of incomplete type"; 4240 break; 4241 } 4242 OS << '\n'; 4243 return; 4244 } 4245 4246 case DependentSequence: 4247 OS << "Dependent sequence: "; 4248 return; 4249 4250 case UserDefinedConversion: 4251 OS << "User-defined conversion sequence: "; 4252 break; 4253 4254 case ConstructorInitialization: 4255 OS << "Constructor initialization sequence: "; 4256 break; 4257 4258 case ReferenceBinding: 4259 OS << "Reference binding: "; 4260 break; 4261 4262 case ListInitialization: 4263 OS << "List initialization: "; 4264 break; 4265 4266 case ZeroInitialization: 4267 OS << "Zero initialization\n"; 4268 return; 4269 4270 case NoInitialization: 4271 OS << "No initialization\n"; 4272 return; 4273 4274 case StandardConversion: 4275 OS << "Standard conversion: "; 4276 break; 4277 4278 case CAssignment: 4279 OS << "C assignment: "; 4280 break; 4281 4282 case StringInit: 4283 OS << "String initialization: "; 4284 break; 4285 } 4286 4287 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) { 4288 if (S != step_begin()) { 4289 OS << " -> "; 4290 } 4291 4292 switch (S->Kind) { 4293 case SK_ResolveAddressOfOverloadedFunction: 4294 OS << "resolve address of overloaded function"; 4295 break; 4296 4297 case SK_CastDerivedToBaseRValue: 4298 OS << "derived-to-base case (rvalue" << S->Type.getAsString() << ")"; 4299 break; 4300 4301 case SK_CastDerivedToBaseLValue: 4302 OS << "derived-to-base case (lvalue" << S->Type.getAsString() << ")"; 4303 break; 4304 4305 case SK_BindReference: 4306 OS << "bind reference to lvalue"; 4307 break; 4308 4309 case SK_BindReferenceToTemporary: 4310 OS << "bind reference to a temporary"; 4311 break; 4312 4313 case SK_ExtraneousCopyToTemporary: 4314 OS << "extraneous C++03 copy to temporary"; 4315 break; 4316 4317 case SK_UserConversion: 4318 OS << "user-defined conversion via " << S->Function.Function; 4319 break; 4320 4321 case SK_QualificationConversionRValue: 4322 OS << "qualification conversion (rvalue)"; 4323 4324 case SK_QualificationConversionLValue: 4325 OS << "qualification conversion (lvalue)"; 4326 break; 4327 4328 case SK_ConversionSequence: 4329 OS << "implicit conversion sequence ("; 4330 S->ICS->DebugPrint(); // FIXME: use OS 4331 OS << ")"; 4332 break; 4333 4334 case SK_ListInitialization: 4335 OS << "list initialization"; 4336 break; 4337 4338 case SK_ConstructorInitialization: 4339 OS << "constructor initialization"; 4340 break; 4341 4342 case SK_ZeroInitialization: 4343 OS << "zero initialization"; 4344 break; 4345 4346 case SK_CAssignment: 4347 OS << "C assignment"; 4348 break; 4349 4350 case SK_StringInit: 4351 OS << "string initialization"; 4352 break; 4353 } 4354 } 4355} 4356 4357void InitializationSequence::dump() const { 4358 dump(llvm::errs()); 4359} 4360 4361//===----------------------------------------------------------------------===// 4362// Initialization helper functions 4363//===----------------------------------------------------------------------===// 4364Sema::OwningExprResult 4365Sema::PerformCopyInitialization(const InitializedEntity &Entity, 4366 SourceLocation EqualLoc, 4367 OwningExprResult Init) { 4368 if (Init.isInvalid()) 4369 return ExprError(); 4370 4371 Expr *InitE = (Expr *)Init.get(); 4372 assert(InitE && "No initialization expression?"); 4373 4374 if (EqualLoc.isInvalid()) 4375 EqualLoc = InitE->getLocStart(); 4376 4377 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(), 4378 EqualLoc); 4379 InitializationSequence Seq(*this, Entity, Kind, &InitE, 1); 4380 Init.release(); 4381 return Seq.Perform(*this, Entity, Kind, 4382 MultiExprArg(*this, (void**)&InitE, 1)); 4383} 4384