SemaInit.cpp revision 5cf86ba6b5a724bf91cb52feade1158f1fbeb605
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->isStructureType() || T->isUnionType()) 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 { 628 // In C, all types are either scalars or aggregates, but 629 // additional handling is needed here for C++ (and possibly others?). 630 assert(0 && "Unsupported initializer type"); 631 } 632} 633 634void InitListChecker::CheckSubElementType(const InitializedEntity &Entity, 635 InitListExpr *IList, 636 QualType ElemType, 637 unsigned &Index, 638 InitListExpr *StructuredList, 639 unsigned &StructuredIndex) { 640 Expr *expr = IList->getInit(Index); 641 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 642 unsigned newIndex = 0; 643 unsigned newStructuredIndex = 0; 644 InitListExpr *newStructuredList 645 = getStructuredSubobjectInit(IList, Index, ElemType, 646 StructuredList, StructuredIndex, 647 SubInitList->getSourceRange()); 648 CheckExplicitInitList(Entity, SubInitList, ElemType, newIndex, 649 newStructuredList, newStructuredIndex); 650 ++StructuredIndex; 651 ++Index; 652 } else if (Expr *Str = IsStringInit(expr, ElemType, SemaRef.Context)) { 653 CheckStringInit(Str, ElemType, SemaRef); 654 UpdateStructuredListElement(StructuredList, StructuredIndex, Str); 655 ++Index; 656 } else if (ElemType->isScalarType()) { 657 CheckScalarType(Entity, IList, ElemType, Index, 658 StructuredList, StructuredIndex); 659 } else if (ElemType->isReferenceType()) { 660 CheckReferenceType(Entity, IList, ElemType, Index, 661 StructuredList, StructuredIndex); 662 } else { 663 if (SemaRef.getLangOptions().CPlusPlus) { 664 // C++ [dcl.init.aggr]p12: 665 // All implicit type conversions (clause 4) are considered when 666 // initializing the aggregate member with an ini- tializer from 667 // an initializer-list. If the initializer can initialize a 668 // member, the member is initialized. [...] 669 670 // FIXME: Better EqualLoc? 671 InitializationKind Kind = 672 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation()); 673 InitializationSequence Seq(SemaRef, Entity, Kind, &expr, 1); 674 675 if (Seq) { 676 Sema::OwningExprResult Result = 677 Seq.Perform(SemaRef, Entity, Kind, 678 Sema::MultiExprArg(SemaRef, (void **)&expr, 1)); 679 if (Result.isInvalid()) 680 hadError = true; 681 682 UpdateStructuredListElement(StructuredList, StructuredIndex, 683 Result.takeAs<Expr>()); 684 ++Index; 685 return; 686 } 687 688 // Fall through for subaggregate initialization 689 } else { 690 // C99 6.7.8p13: 691 // 692 // The initializer for a structure or union object that has 693 // automatic storage duration shall be either an initializer 694 // list as described below, or a single expression that has 695 // compatible structure or union type. In the latter case, the 696 // initial value of the object, including unnamed members, is 697 // that of the expression. 698 if ((ElemType->isRecordType() || ElemType->isVectorType()) && 699 SemaRef.Context.hasSameUnqualifiedType(expr->getType(), ElemType)) { 700 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 701 ++Index; 702 return; 703 } 704 705 // Fall through for subaggregate initialization 706 } 707 708 // C++ [dcl.init.aggr]p12: 709 // 710 // [...] Otherwise, if the member is itself a non-empty 711 // subaggregate, brace elision is assumed and the initializer is 712 // considered for the initialization of the first member of 713 // the subaggregate. 714 if (ElemType->isAggregateType() || ElemType->isVectorType()) { 715 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList, 716 StructuredIndex); 717 ++StructuredIndex; 718 } else { 719 // We cannot initialize this element, so let 720 // PerformCopyInitialization produce the appropriate diagnostic. 721 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), 722 SemaRef.Owned(expr)); 723 IList->setInit(Index, 0); 724 hadError = true; 725 ++Index; 726 ++StructuredIndex; 727 } 728 } 729} 730 731void InitListChecker::CheckScalarType(const InitializedEntity &Entity, 732 InitListExpr *IList, QualType DeclType, 733 unsigned &Index, 734 InitListExpr *StructuredList, 735 unsigned &StructuredIndex) { 736 if (Index < IList->getNumInits()) { 737 Expr *expr = IList->getInit(Index); 738 if (isa<InitListExpr>(expr)) { 739 SemaRef.Diag(IList->getLocStart(), 740 diag::err_many_braces_around_scalar_init) 741 << IList->getSourceRange(); 742 hadError = true; 743 ++Index; 744 ++StructuredIndex; 745 return; 746 } else if (isa<DesignatedInitExpr>(expr)) { 747 SemaRef.Diag(expr->getSourceRange().getBegin(), 748 diag::err_designator_for_scalar_init) 749 << DeclType << expr->getSourceRange(); 750 hadError = true; 751 ++Index; 752 ++StructuredIndex; 753 return; 754 } 755 756 Sema::OwningExprResult Result = 757 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 758 SemaRef.Owned(expr)); 759 760 Expr *ResultExpr = 0; 761 762 if (Result.isInvalid()) 763 hadError = true; // types weren't compatible. 764 else { 765 ResultExpr = Result.takeAs<Expr>(); 766 767 if (ResultExpr != expr) { 768 // The type was promoted, update initializer list. 769 IList->setInit(Index, ResultExpr); 770 } 771 } 772 if (hadError) 773 ++StructuredIndex; 774 else 775 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr); 776 ++Index; 777 } else { 778 SemaRef.Diag(IList->getLocStart(), diag::err_empty_scalar_initializer) 779 << IList->getSourceRange(); 780 hadError = true; 781 ++Index; 782 ++StructuredIndex; 783 return; 784 } 785} 786 787void InitListChecker::CheckReferenceType(const InitializedEntity &Entity, 788 InitListExpr *IList, QualType DeclType, 789 unsigned &Index, 790 InitListExpr *StructuredList, 791 unsigned &StructuredIndex) { 792 if (Index < IList->getNumInits()) { 793 Expr *expr = IList->getInit(Index); 794 if (isa<InitListExpr>(expr)) { 795 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) 796 << DeclType << IList->getSourceRange(); 797 hadError = true; 798 ++Index; 799 ++StructuredIndex; 800 return; 801 } 802 803 Sema::OwningExprResult Result = 804 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 805 SemaRef.Owned(expr)); 806 807 if (Result.isInvalid()) 808 hadError = true; 809 810 expr = Result.takeAs<Expr>(); 811 IList->setInit(Index, expr); 812 813 if (hadError) 814 ++StructuredIndex; 815 else 816 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 817 ++Index; 818 } else { 819 // FIXME: It would be wonderful if we could point at the actual member. In 820 // general, it would be useful to pass location information down the stack, 821 // so that we know the location (or decl) of the "current object" being 822 // initialized. 823 SemaRef.Diag(IList->getLocStart(), 824 diag::err_init_reference_member_uninitialized) 825 << DeclType 826 << IList->getSourceRange(); 827 hadError = true; 828 ++Index; 829 ++StructuredIndex; 830 return; 831 } 832} 833 834void InitListChecker::CheckVectorType(const InitializedEntity &Entity, 835 InitListExpr *IList, QualType DeclType, 836 unsigned &Index, 837 InitListExpr *StructuredList, 838 unsigned &StructuredIndex) { 839 if (Index < IList->getNumInits()) { 840 const VectorType *VT = DeclType->getAs<VectorType>(); 841 unsigned maxElements = VT->getNumElements(); 842 unsigned numEltsInit = 0; 843 QualType elementType = VT->getElementType(); 844 845 if (!SemaRef.getLangOptions().OpenCL) { 846 InitializedEntity ElementEntity = 847 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 848 849 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) { 850 // Don't attempt to go past the end of the init list 851 if (Index >= IList->getNumInits()) 852 break; 853 854 ElementEntity.setElementIndex(Index); 855 CheckSubElementType(ElementEntity, IList, elementType, Index, 856 StructuredList, StructuredIndex); 857 } 858 } else { 859 InitializedEntity ElementEntity = 860 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 861 862 // OpenCL initializers allows vectors to be constructed from vectors. 863 for (unsigned i = 0; i < maxElements; ++i) { 864 // Don't attempt to go past the end of the init list 865 if (Index >= IList->getNumInits()) 866 break; 867 868 ElementEntity.setElementIndex(Index); 869 870 QualType IType = IList->getInit(Index)->getType(); 871 if (!IType->isVectorType()) { 872 CheckSubElementType(ElementEntity, IList, elementType, Index, 873 StructuredList, StructuredIndex); 874 ++numEltsInit; 875 } else { 876 const VectorType *IVT = IType->getAs<VectorType>(); 877 unsigned numIElts = IVT->getNumElements(); 878 QualType VecType = SemaRef.Context.getExtVectorType(elementType, 879 numIElts); 880 CheckSubElementType(ElementEntity, IList, VecType, Index, 881 StructuredList, StructuredIndex); 882 numEltsInit += numIElts; 883 } 884 } 885 } 886 887 // OpenCL requires all elements to be initialized. 888 if (numEltsInit != maxElements) 889 if (SemaRef.getLangOptions().OpenCL) 890 SemaRef.Diag(IList->getSourceRange().getBegin(), 891 diag::err_vector_incorrect_num_initializers) 892 << (numEltsInit < maxElements) << maxElements << numEltsInit; 893 } 894} 895 896void InitListChecker::CheckArrayType(const InitializedEntity &Entity, 897 InitListExpr *IList, QualType &DeclType, 898 llvm::APSInt elementIndex, 899 bool SubobjectIsDesignatorContext, 900 unsigned &Index, 901 InitListExpr *StructuredList, 902 unsigned &StructuredIndex) { 903 // Check for the special-case of initializing an array with a string. 904 if (Index < IList->getNumInits()) { 905 if (Expr *Str = IsStringInit(IList->getInit(Index), DeclType, 906 SemaRef.Context)) { 907 CheckStringInit(Str, DeclType, SemaRef); 908 // We place the string literal directly into the resulting 909 // initializer list. This is the only place where the structure 910 // of the structured initializer list doesn't match exactly, 911 // because doing so would involve allocating one character 912 // constant for each string. 913 UpdateStructuredListElement(StructuredList, StructuredIndex, Str); 914 StructuredList->resizeInits(SemaRef.Context, StructuredIndex); 915 ++Index; 916 return; 917 } 918 } 919 if (const VariableArrayType *VAT = 920 SemaRef.Context.getAsVariableArrayType(DeclType)) { 921 // Check for VLAs; in standard C it would be possible to check this 922 // earlier, but I don't know where clang accepts VLAs (gcc accepts 923 // them in all sorts of strange places). 924 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(), 925 diag::err_variable_object_no_init) 926 << VAT->getSizeExpr()->getSourceRange(); 927 hadError = true; 928 ++Index; 929 ++StructuredIndex; 930 return; 931 } 932 933 // We might know the maximum number of elements in advance. 934 llvm::APSInt maxElements(elementIndex.getBitWidth(), 935 elementIndex.isUnsigned()); 936 bool maxElementsKnown = false; 937 if (const ConstantArrayType *CAT = 938 SemaRef.Context.getAsConstantArrayType(DeclType)) { 939 maxElements = CAT->getSize(); 940 elementIndex.extOrTrunc(maxElements.getBitWidth()); 941 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 942 maxElementsKnown = true; 943 } 944 945 QualType elementType = SemaRef.Context.getAsArrayType(DeclType) 946 ->getElementType(); 947 while (Index < IList->getNumInits()) { 948 Expr *Init = IList->getInit(Index); 949 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 950 // If we're not the subobject that matches up with the '{' for 951 // the designator, we shouldn't be handling the 952 // designator. Return immediately. 953 if (!SubobjectIsDesignatorContext) 954 return; 955 956 // Handle this designated initializer. elementIndex will be 957 // updated to be the next array element we'll initialize. 958 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 959 DeclType, 0, &elementIndex, Index, 960 StructuredList, StructuredIndex, true, 961 false)) { 962 hadError = true; 963 continue; 964 } 965 966 if (elementIndex.getBitWidth() > maxElements.getBitWidth()) 967 maxElements.extend(elementIndex.getBitWidth()); 968 else if (elementIndex.getBitWidth() < maxElements.getBitWidth()) 969 elementIndex.extend(maxElements.getBitWidth()); 970 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 971 972 // If the array is of incomplete type, keep track of the number of 973 // elements in the initializer. 974 if (!maxElementsKnown && elementIndex > maxElements) 975 maxElements = elementIndex; 976 977 continue; 978 } 979 980 // If we know the maximum number of elements, and we've already 981 // hit it, stop consuming elements in the initializer list. 982 if (maxElementsKnown && elementIndex == maxElements) 983 break; 984 985 InitializedEntity ElementEntity = 986 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex, 987 Entity); 988 // Check this element. 989 CheckSubElementType(ElementEntity, IList, elementType, Index, 990 StructuredList, StructuredIndex); 991 ++elementIndex; 992 993 // If the array is of incomplete type, keep track of the number of 994 // elements in the initializer. 995 if (!maxElementsKnown && elementIndex > maxElements) 996 maxElements = elementIndex; 997 } 998 if (!hadError && DeclType->isIncompleteArrayType()) { 999 // If this is an incomplete array type, the actual type needs to 1000 // be calculated here. 1001 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned()); 1002 if (maxElements == Zero) { 1003 // Sizing an array implicitly to zero is not allowed by ISO C, 1004 // but is supported by GNU. 1005 SemaRef.Diag(IList->getLocStart(), 1006 diag::ext_typecheck_zero_array_size); 1007 } 1008 1009 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements, 1010 ArrayType::Normal, 0); 1011 } 1012} 1013 1014void InitListChecker::CheckStructUnionTypes(const InitializedEntity &Entity, 1015 InitListExpr *IList, 1016 QualType DeclType, 1017 RecordDecl::field_iterator Field, 1018 bool SubobjectIsDesignatorContext, 1019 unsigned &Index, 1020 InitListExpr *StructuredList, 1021 unsigned &StructuredIndex, 1022 bool TopLevelObject) { 1023 RecordDecl* structDecl = DeclType->getAs<RecordType>()->getDecl(); 1024 1025 // If the record is invalid, some of it's members are invalid. To avoid 1026 // confusion, we forgo checking the intializer for the entire record. 1027 if (structDecl->isInvalidDecl()) { 1028 hadError = true; 1029 return; 1030 } 1031 1032 if (DeclType->isUnionType() && IList->getNumInits() == 0) { 1033 // Value-initialize the first named member of the union. 1034 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1035 for (RecordDecl::field_iterator FieldEnd = RD->field_end(); 1036 Field != FieldEnd; ++Field) { 1037 if (Field->getDeclName()) { 1038 StructuredList->setInitializedFieldInUnion(*Field); 1039 break; 1040 } 1041 } 1042 return; 1043 } 1044 1045 // If structDecl is a forward declaration, this loop won't do 1046 // anything except look at designated initializers; That's okay, 1047 // because an error should get printed out elsewhere. It might be 1048 // worthwhile to skip over the rest of the initializer, though. 1049 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1050 RecordDecl::field_iterator FieldEnd = RD->field_end(); 1051 bool InitializedSomething = false; 1052 bool CheckForMissingFields = true; 1053 while (Index < IList->getNumInits()) { 1054 Expr *Init = IList->getInit(Index); 1055 1056 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 1057 // If we're not the subobject that matches up with the '{' for 1058 // the designator, we shouldn't be handling the 1059 // designator. Return immediately. 1060 if (!SubobjectIsDesignatorContext) 1061 return; 1062 1063 // Handle this designated initializer. Field will be updated to 1064 // the next field that we'll be initializing. 1065 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 1066 DeclType, &Field, 0, Index, 1067 StructuredList, StructuredIndex, 1068 true, TopLevelObject)) 1069 hadError = true; 1070 1071 InitializedSomething = true; 1072 1073 // Disable check for missing fields when designators are used. 1074 // This matches gcc behaviour. 1075 CheckForMissingFields = false; 1076 continue; 1077 } 1078 1079 if (Field == FieldEnd) { 1080 // We've run out of fields. We're done. 1081 break; 1082 } 1083 1084 // We've already initialized a member of a union. We're done. 1085 if (InitializedSomething && DeclType->isUnionType()) 1086 break; 1087 1088 // If we've hit the flexible array member at the end, we're done. 1089 if (Field->getType()->isIncompleteArrayType()) 1090 break; 1091 1092 if (Field->isUnnamedBitfield()) { 1093 // Don't initialize unnamed bitfields, e.g. "int : 20;" 1094 ++Field; 1095 continue; 1096 } 1097 1098 InitializedEntity MemberEntity = 1099 InitializedEntity::InitializeMember(*Field, &Entity); 1100 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1101 StructuredList, StructuredIndex); 1102 InitializedSomething = true; 1103 1104 if (DeclType->isUnionType()) { 1105 // Initialize the first field within the union. 1106 StructuredList->setInitializedFieldInUnion(*Field); 1107 } 1108 1109 ++Field; 1110 } 1111 1112 // Emit warnings for missing struct field initializers. 1113 if (CheckForMissingFields && Field != FieldEnd && 1114 !Field->getType()->isIncompleteArrayType() && !DeclType->isUnionType()) { 1115 // It is possible we have one or more unnamed bitfields remaining. 1116 // Find first (if any) named field and emit warning. 1117 for (RecordDecl::field_iterator it = Field, end = RD->field_end(); 1118 it != end; ++it) { 1119 if (!it->isUnnamedBitfield()) { 1120 SemaRef.Diag(IList->getSourceRange().getEnd(), 1121 diag::warn_missing_field_initializers) << it->getName(); 1122 break; 1123 } 1124 } 1125 } 1126 1127 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() || 1128 Index >= IList->getNumInits()) 1129 return; 1130 1131 // Handle GNU flexible array initializers. 1132 if (!TopLevelObject && 1133 (!isa<InitListExpr>(IList->getInit(Index)) || 1134 cast<InitListExpr>(IList->getInit(Index))->getNumInits() > 0)) { 1135 SemaRef.Diag(IList->getInit(Index)->getSourceRange().getBegin(), 1136 diag::err_flexible_array_init_nonempty) 1137 << IList->getInit(Index)->getSourceRange().getBegin(); 1138 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1139 << *Field; 1140 hadError = true; 1141 ++Index; 1142 return; 1143 } else { 1144 SemaRef.Diag(IList->getInit(Index)->getSourceRange().getBegin(), 1145 diag::ext_flexible_array_init) 1146 << IList->getInit(Index)->getSourceRange().getBegin(); 1147 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1148 << *Field; 1149 } 1150 1151 InitializedEntity MemberEntity = 1152 InitializedEntity::InitializeMember(*Field, &Entity); 1153 1154 if (isa<InitListExpr>(IList->getInit(Index))) 1155 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1156 StructuredList, StructuredIndex); 1157 else 1158 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index, 1159 StructuredList, StructuredIndex); 1160} 1161 1162/// \brief Expand a field designator that refers to a member of an 1163/// anonymous struct or union into a series of field designators that 1164/// refers to the field within the appropriate subobject. 1165/// 1166/// Field/FieldIndex will be updated to point to the (new) 1167/// currently-designated field. 1168static void ExpandAnonymousFieldDesignator(Sema &SemaRef, 1169 DesignatedInitExpr *DIE, 1170 unsigned DesigIdx, 1171 FieldDecl *Field, 1172 RecordDecl::field_iterator &FieldIter, 1173 unsigned &FieldIndex) { 1174 typedef DesignatedInitExpr::Designator Designator; 1175 1176 // Build the path from the current object to the member of the 1177 // anonymous struct/union (backwards). 1178 llvm::SmallVector<FieldDecl *, 4> Path; 1179 SemaRef.BuildAnonymousStructUnionMemberPath(Field, Path); 1180 1181 // Build the replacement designators. 1182 llvm::SmallVector<Designator, 4> Replacements; 1183 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 1184 FI = Path.rbegin(), FIEnd = Path.rend(); 1185 FI != FIEnd; ++FI) { 1186 if (FI + 1 == FIEnd) 1187 Replacements.push_back(Designator((IdentifierInfo *)0, 1188 DIE->getDesignator(DesigIdx)->getDotLoc(), 1189 DIE->getDesignator(DesigIdx)->getFieldLoc())); 1190 else 1191 Replacements.push_back(Designator((IdentifierInfo *)0, SourceLocation(), 1192 SourceLocation())); 1193 Replacements.back().setField(*FI); 1194 } 1195 1196 // Expand the current designator into the set of replacement 1197 // designators, so we have a full subobject path down to where the 1198 // member of the anonymous struct/union is actually stored. 1199 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0], 1200 &Replacements[0] + Replacements.size()); 1201 1202 // Update FieldIter/FieldIndex; 1203 RecordDecl *Record = cast<RecordDecl>(Path.back()->getDeclContext()); 1204 FieldIter = Record->field_begin(); 1205 FieldIndex = 0; 1206 for (RecordDecl::field_iterator FEnd = Record->field_end(); 1207 FieldIter != FEnd; ++FieldIter) { 1208 if (FieldIter->isUnnamedBitfield()) 1209 continue; 1210 1211 if (*FieldIter == Path.back()) 1212 return; 1213 1214 ++FieldIndex; 1215 } 1216 1217 assert(false && "Unable to find anonymous struct/union field"); 1218} 1219 1220/// @brief Check the well-formedness of a C99 designated initializer. 1221/// 1222/// Determines whether the designated initializer @p DIE, which 1223/// resides at the given @p Index within the initializer list @p 1224/// IList, is well-formed for a current object of type @p DeclType 1225/// (C99 6.7.8). The actual subobject that this designator refers to 1226/// within the current subobject is returned in either 1227/// @p NextField or @p NextElementIndex (whichever is appropriate). 1228/// 1229/// @param IList The initializer list in which this designated 1230/// initializer occurs. 1231/// 1232/// @param DIE The designated initializer expression. 1233/// 1234/// @param DesigIdx The index of the current designator. 1235/// 1236/// @param DeclType The type of the "current object" (C99 6.7.8p17), 1237/// into which the designation in @p DIE should refer. 1238/// 1239/// @param NextField If non-NULL and the first designator in @p DIE is 1240/// a field, this will be set to the field declaration corresponding 1241/// to the field named by the designator. 1242/// 1243/// @param NextElementIndex If non-NULL and the first designator in @p 1244/// DIE is an array designator or GNU array-range designator, this 1245/// will be set to the last index initialized by this designator. 1246/// 1247/// @param Index Index into @p IList where the designated initializer 1248/// @p DIE occurs. 1249/// 1250/// @param StructuredList The initializer list expression that 1251/// describes all of the subobject initializers in the order they'll 1252/// actually be initialized. 1253/// 1254/// @returns true if there was an error, false otherwise. 1255bool 1256InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, 1257 InitListExpr *IList, 1258 DesignatedInitExpr *DIE, 1259 unsigned DesigIdx, 1260 QualType &CurrentObjectType, 1261 RecordDecl::field_iterator *NextField, 1262 llvm::APSInt *NextElementIndex, 1263 unsigned &Index, 1264 InitListExpr *StructuredList, 1265 unsigned &StructuredIndex, 1266 bool FinishSubobjectInit, 1267 bool TopLevelObject) { 1268 if (DesigIdx == DIE->size()) { 1269 // Check the actual initialization for the designated object type. 1270 bool prevHadError = hadError; 1271 1272 // Temporarily remove the designator expression from the 1273 // initializer list that the child calls see, so that we don't try 1274 // to re-process the designator. 1275 unsigned OldIndex = Index; 1276 IList->setInit(OldIndex, DIE->getInit()); 1277 1278 CheckSubElementType(Entity, IList, CurrentObjectType, Index, 1279 StructuredList, StructuredIndex); 1280 1281 // Restore the designated initializer expression in the syntactic 1282 // form of the initializer list. 1283 if (IList->getInit(OldIndex) != DIE->getInit()) 1284 DIE->setInit(IList->getInit(OldIndex)); 1285 IList->setInit(OldIndex, DIE); 1286 1287 return hadError && !prevHadError; 1288 } 1289 1290 bool IsFirstDesignator = (DesigIdx == 0); 1291 assert((IsFirstDesignator || StructuredList) && 1292 "Need a non-designated initializer list to start from"); 1293 1294 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx); 1295 // Determine the structural initializer list that corresponds to the 1296 // current subobject. 1297 StructuredList = IsFirstDesignator? SyntacticToSemantic[IList] 1298 : getStructuredSubobjectInit(IList, Index, CurrentObjectType, 1299 StructuredList, StructuredIndex, 1300 SourceRange(D->getStartLocation(), 1301 DIE->getSourceRange().getEnd())); 1302 assert(StructuredList && "Expected a structured initializer list"); 1303 1304 if (D->isFieldDesignator()) { 1305 // C99 6.7.8p7: 1306 // 1307 // If a designator has the form 1308 // 1309 // . identifier 1310 // 1311 // then the current object (defined below) shall have 1312 // structure or union type and the identifier shall be the 1313 // name of a member of that type. 1314 const RecordType *RT = CurrentObjectType->getAs<RecordType>(); 1315 if (!RT) { 1316 SourceLocation Loc = D->getDotLoc(); 1317 if (Loc.isInvalid()) 1318 Loc = D->getFieldLoc(); 1319 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr) 1320 << SemaRef.getLangOptions().CPlusPlus << CurrentObjectType; 1321 ++Index; 1322 return true; 1323 } 1324 1325 // Note: we perform a linear search of the fields here, despite 1326 // the fact that we have a faster lookup method, because we always 1327 // need to compute the field's index. 1328 FieldDecl *KnownField = D->getField(); 1329 IdentifierInfo *FieldName = D->getFieldName(); 1330 unsigned FieldIndex = 0; 1331 RecordDecl::field_iterator 1332 Field = RT->getDecl()->field_begin(), 1333 FieldEnd = RT->getDecl()->field_end(); 1334 for (; Field != FieldEnd; ++Field) { 1335 if (Field->isUnnamedBitfield()) 1336 continue; 1337 1338 if (KnownField == *Field || Field->getIdentifier() == FieldName) 1339 break; 1340 1341 ++FieldIndex; 1342 } 1343 1344 if (Field == FieldEnd) { 1345 // There was no normal field in the struct with the designated 1346 // name. Perform another lookup for this name, which may find 1347 // something that we can't designate (e.g., a member function), 1348 // may find nothing, or may find a member of an anonymous 1349 // struct/union. 1350 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName); 1351 FieldDecl *ReplacementField = 0; 1352 if (Lookup.first == Lookup.second) { 1353 // Name lookup didn't find anything. Determine whether this 1354 // was a typo for another field name. 1355 LookupResult R(SemaRef, FieldName, D->getFieldLoc(), 1356 Sema::LookupMemberName); 1357 if (SemaRef.CorrectTypo(R, /*Scope=*/0, /*SS=*/0, RT->getDecl(), false, 1358 Sema::CTC_NoKeywords) && 1359 (ReplacementField = R.getAsSingle<FieldDecl>()) && 1360 ReplacementField->getDeclContext()->getLookupContext() 1361 ->Equals(RT->getDecl())) { 1362 SemaRef.Diag(D->getFieldLoc(), 1363 diag::err_field_designator_unknown_suggest) 1364 << FieldName << CurrentObjectType << R.getLookupName() 1365 << FixItHint::CreateReplacement(D->getFieldLoc(), 1366 R.getLookupName().getAsString()); 1367 SemaRef.Diag(ReplacementField->getLocation(), 1368 diag::note_previous_decl) 1369 << ReplacementField->getDeclName(); 1370 } else { 1371 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown) 1372 << FieldName << CurrentObjectType; 1373 ++Index; 1374 return true; 1375 } 1376 } else if (!KnownField) { 1377 // Determine whether we found a field at all. 1378 ReplacementField = dyn_cast<FieldDecl>(*Lookup.first); 1379 } 1380 1381 if (!ReplacementField) { 1382 // Name lookup found something, but it wasn't a field. 1383 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield) 1384 << FieldName; 1385 SemaRef.Diag((*Lookup.first)->getLocation(), 1386 diag::note_field_designator_found); 1387 ++Index; 1388 return true; 1389 } 1390 1391 if (!KnownField && 1392 cast<RecordDecl>((ReplacementField)->getDeclContext()) 1393 ->isAnonymousStructOrUnion()) { 1394 // Handle an field designator that refers to a member of an 1395 // anonymous struct or union. 1396 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, 1397 ReplacementField, 1398 Field, FieldIndex); 1399 D = DIE->getDesignator(DesigIdx); 1400 } else if (!KnownField) { 1401 // The replacement field comes from typo correction; find it 1402 // in the list of fields. 1403 FieldIndex = 0; 1404 Field = RT->getDecl()->field_begin(); 1405 for (; Field != FieldEnd; ++Field) { 1406 if (Field->isUnnamedBitfield()) 1407 continue; 1408 1409 if (ReplacementField == *Field || 1410 Field->getIdentifier() == ReplacementField->getIdentifier()) 1411 break; 1412 1413 ++FieldIndex; 1414 } 1415 } 1416 } else if (!KnownField && 1417 cast<RecordDecl>((*Field)->getDeclContext()) 1418 ->isAnonymousStructOrUnion()) { 1419 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, *Field, 1420 Field, FieldIndex); 1421 D = DIE->getDesignator(DesigIdx); 1422 } 1423 1424 // All of the fields of a union are located at the same place in 1425 // the initializer list. 1426 if (RT->getDecl()->isUnion()) { 1427 FieldIndex = 0; 1428 StructuredList->setInitializedFieldInUnion(*Field); 1429 } 1430 1431 // Update the designator with the field declaration. 1432 D->setField(*Field); 1433 1434 // Make sure that our non-designated initializer list has space 1435 // for a subobject corresponding to this field. 1436 if (FieldIndex >= StructuredList->getNumInits()) 1437 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1); 1438 1439 // This designator names a flexible array member. 1440 if (Field->getType()->isIncompleteArrayType()) { 1441 bool Invalid = false; 1442 if ((DesigIdx + 1) != DIE->size()) { 1443 // We can't designate an object within the flexible array 1444 // member (because GCC doesn't allow it). 1445 DesignatedInitExpr::Designator *NextD 1446 = DIE->getDesignator(DesigIdx + 1); 1447 SemaRef.Diag(NextD->getStartLocation(), 1448 diag::err_designator_into_flexible_array_member) 1449 << SourceRange(NextD->getStartLocation(), 1450 DIE->getSourceRange().getEnd()); 1451 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1452 << *Field; 1453 Invalid = true; 1454 } 1455 1456 if (!hadError && !isa<InitListExpr>(DIE->getInit())) { 1457 // The initializer is not an initializer list. 1458 SemaRef.Diag(DIE->getInit()->getSourceRange().getBegin(), 1459 diag::err_flexible_array_init_needs_braces) 1460 << DIE->getInit()->getSourceRange(); 1461 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1462 << *Field; 1463 Invalid = true; 1464 } 1465 1466 // Handle GNU flexible array initializers. 1467 if (!Invalid && !TopLevelObject && 1468 cast<InitListExpr>(DIE->getInit())->getNumInits() > 0) { 1469 SemaRef.Diag(DIE->getSourceRange().getBegin(), 1470 diag::err_flexible_array_init_nonempty) 1471 << DIE->getSourceRange().getBegin(); 1472 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1473 << *Field; 1474 Invalid = true; 1475 } 1476 1477 if (Invalid) { 1478 ++Index; 1479 return true; 1480 } 1481 1482 // Initialize the array. 1483 bool prevHadError = hadError; 1484 unsigned newStructuredIndex = FieldIndex; 1485 unsigned OldIndex = Index; 1486 IList->setInit(Index, DIE->getInit()); 1487 1488 InitializedEntity MemberEntity = 1489 InitializedEntity::InitializeMember(*Field, &Entity); 1490 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1491 StructuredList, newStructuredIndex); 1492 1493 IList->setInit(OldIndex, DIE); 1494 if (hadError && !prevHadError) { 1495 ++Field; 1496 ++FieldIndex; 1497 if (NextField) 1498 *NextField = Field; 1499 StructuredIndex = FieldIndex; 1500 return true; 1501 } 1502 } else { 1503 // Recurse to check later designated subobjects. 1504 QualType FieldType = (*Field)->getType(); 1505 unsigned newStructuredIndex = FieldIndex; 1506 1507 InitializedEntity MemberEntity = 1508 InitializedEntity::InitializeMember(*Field, &Entity); 1509 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1, 1510 FieldType, 0, 0, Index, 1511 StructuredList, newStructuredIndex, 1512 true, false)) 1513 return true; 1514 } 1515 1516 // Find the position of the next field to be initialized in this 1517 // subobject. 1518 ++Field; 1519 ++FieldIndex; 1520 1521 // If this the first designator, our caller will continue checking 1522 // the rest of this struct/class/union subobject. 1523 if (IsFirstDesignator) { 1524 if (NextField) 1525 *NextField = Field; 1526 StructuredIndex = FieldIndex; 1527 return false; 1528 } 1529 1530 if (!FinishSubobjectInit) 1531 return false; 1532 1533 // We've already initialized something in the union; we're done. 1534 if (RT->getDecl()->isUnion()) 1535 return hadError; 1536 1537 // Check the remaining fields within this class/struct/union subobject. 1538 bool prevHadError = hadError; 1539 1540 CheckStructUnionTypes(Entity, IList, CurrentObjectType, Field, false, Index, 1541 StructuredList, FieldIndex); 1542 return hadError && !prevHadError; 1543 } 1544 1545 // C99 6.7.8p6: 1546 // 1547 // If a designator has the form 1548 // 1549 // [ constant-expression ] 1550 // 1551 // then the current object (defined below) shall have array 1552 // type and the expression shall be an integer constant 1553 // expression. If the array is of unknown size, any 1554 // nonnegative value is valid. 1555 // 1556 // Additionally, cope with the GNU extension that permits 1557 // designators of the form 1558 // 1559 // [ constant-expression ... constant-expression ] 1560 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType); 1561 if (!AT) { 1562 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array) 1563 << CurrentObjectType; 1564 ++Index; 1565 return true; 1566 } 1567 1568 Expr *IndexExpr = 0; 1569 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex; 1570 if (D->isArrayDesignator()) { 1571 IndexExpr = DIE->getArrayIndex(*D); 1572 DesignatedStartIndex = IndexExpr->EvaluateAsInt(SemaRef.Context); 1573 DesignatedEndIndex = DesignatedStartIndex; 1574 } else { 1575 assert(D->isArrayRangeDesignator() && "Need array-range designator"); 1576 1577 1578 DesignatedStartIndex = 1579 DIE->getArrayRangeStart(*D)->EvaluateAsInt(SemaRef.Context); 1580 DesignatedEndIndex = 1581 DIE->getArrayRangeEnd(*D)->EvaluateAsInt(SemaRef.Context); 1582 IndexExpr = DIE->getArrayRangeEnd(*D); 1583 1584 if (DesignatedStartIndex.getZExtValue() !=DesignatedEndIndex.getZExtValue()) 1585 FullyStructuredList->sawArrayRangeDesignator(); 1586 } 1587 1588 if (isa<ConstantArrayType>(AT)) { 1589 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false); 1590 DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth()); 1591 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned()); 1592 DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth()); 1593 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned()); 1594 if (DesignatedEndIndex >= MaxElements) { 1595 SemaRef.Diag(IndexExpr->getSourceRange().getBegin(), 1596 diag::err_array_designator_too_large) 1597 << DesignatedEndIndex.toString(10) << MaxElements.toString(10) 1598 << IndexExpr->getSourceRange(); 1599 ++Index; 1600 return true; 1601 } 1602 } else { 1603 // Make sure the bit-widths and signedness match. 1604 if (DesignatedStartIndex.getBitWidth() > DesignatedEndIndex.getBitWidth()) 1605 DesignatedEndIndex.extend(DesignatedStartIndex.getBitWidth()); 1606 else if (DesignatedStartIndex.getBitWidth() < 1607 DesignatedEndIndex.getBitWidth()) 1608 DesignatedStartIndex.extend(DesignatedEndIndex.getBitWidth()); 1609 DesignatedStartIndex.setIsUnsigned(true); 1610 DesignatedEndIndex.setIsUnsigned(true); 1611 } 1612 1613 // Make sure that our non-designated initializer list has space 1614 // for a subobject corresponding to this array element. 1615 if (DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits()) 1616 StructuredList->resizeInits(SemaRef.Context, 1617 DesignatedEndIndex.getZExtValue() + 1); 1618 1619 // Repeatedly perform subobject initializations in the range 1620 // [DesignatedStartIndex, DesignatedEndIndex]. 1621 1622 // Move to the next designator 1623 unsigned ElementIndex = DesignatedStartIndex.getZExtValue(); 1624 unsigned OldIndex = Index; 1625 1626 InitializedEntity ElementEntity = 1627 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1628 1629 while (DesignatedStartIndex <= DesignatedEndIndex) { 1630 // Recurse to check later designated subobjects. 1631 QualType ElementType = AT->getElementType(); 1632 Index = OldIndex; 1633 1634 ElementEntity.setElementIndex(ElementIndex); 1635 if (CheckDesignatedInitializer(ElementEntity, IList, DIE, DesigIdx + 1, 1636 ElementType, 0, 0, Index, 1637 StructuredList, ElementIndex, 1638 (DesignatedStartIndex == DesignatedEndIndex), 1639 false)) 1640 return true; 1641 1642 // Move to the next index in the array that we'll be initializing. 1643 ++DesignatedStartIndex; 1644 ElementIndex = DesignatedStartIndex.getZExtValue(); 1645 } 1646 1647 // If this the first designator, our caller will continue checking 1648 // the rest of this array subobject. 1649 if (IsFirstDesignator) { 1650 if (NextElementIndex) 1651 *NextElementIndex = DesignatedStartIndex; 1652 StructuredIndex = ElementIndex; 1653 return false; 1654 } 1655 1656 if (!FinishSubobjectInit) 1657 return false; 1658 1659 // Check the remaining elements within this array subobject. 1660 bool prevHadError = hadError; 1661 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex, 1662 /*SubobjectIsDesignatorContext=*/false, Index, 1663 StructuredList, ElementIndex); 1664 return hadError && !prevHadError; 1665} 1666 1667// Get the structured initializer list for a subobject of type 1668// @p CurrentObjectType. 1669InitListExpr * 1670InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 1671 QualType CurrentObjectType, 1672 InitListExpr *StructuredList, 1673 unsigned StructuredIndex, 1674 SourceRange InitRange) { 1675 Expr *ExistingInit = 0; 1676 if (!StructuredList) 1677 ExistingInit = SyntacticToSemantic[IList]; 1678 else if (StructuredIndex < StructuredList->getNumInits()) 1679 ExistingInit = StructuredList->getInit(StructuredIndex); 1680 1681 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit)) 1682 return Result; 1683 1684 if (ExistingInit) { 1685 // We are creating an initializer list that initializes the 1686 // subobjects of the current object, but there was already an 1687 // initialization that completely initialized the current 1688 // subobject, e.g., by a compound literal: 1689 // 1690 // struct X { int a, b; }; 1691 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 }; 1692 // 1693 // Here, xs[0].a == 0 and xs[0].b == 3, since the second, 1694 // designated initializer re-initializes the whole 1695 // subobject [0], overwriting previous initializers. 1696 SemaRef.Diag(InitRange.getBegin(), 1697 diag::warn_subobject_initializer_overrides) 1698 << InitRange; 1699 SemaRef.Diag(ExistingInit->getSourceRange().getBegin(), 1700 diag::note_previous_initializer) 1701 << /*FIXME:has side effects=*/0 1702 << ExistingInit->getSourceRange(); 1703 } 1704 1705 InitListExpr *Result 1706 = new (SemaRef.Context) InitListExpr(SemaRef.Context, 1707 InitRange.getBegin(), 0, 0, 1708 InitRange.getEnd()); 1709 1710 Result->setType(CurrentObjectType.getNonReferenceType()); 1711 1712 // Pre-allocate storage for the structured initializer list. 1713 unsigned NumElements = 0; 1714 unsigned NumInits = 0; 1715 if (!StructuredList) 1716 NumInits = IList->getNumInits(); 1717 else if (Index < IList->getNumInits()) { 1718 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) 1719 NumInits = SubList->getNumInits(); 1720 } 1721 1722 if (const ArrayType *AType 1723 = SemaRef.Context.getAsArrayType(CurrentObjectType)) { 1724 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) { 1725 NumElements = CAType->getSize().getZExtValue(); 1726 // Simple heuristic so that we don't allocate a very large 1727 // initializer with many empty entries at the end. 1728 if (NumInits && NumElements > NumInits) 1729 NumElements = 0; 1730 } 1731 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>()) 1732 NumElements = VType->getNumElements(); 1733 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) { 1734 RecordDecl *RDecl = RType->getDecl(); 1735 if (RDecl->isUnion()) 1736 NumElements = 1; 1737 else 1738 NumElements = std::distance(RDecl->field_begin(), 1739 RDecl->field_end()); 1740 } 1741 1742 if (NumElements < NumInits) 1743 NumElements = IList->getNumInits(); 1744 1745 Result->reserveInits(SemaRef.Context, NumElements); 1746 1747 // Link this new initializer list into the structured initializer 1748 // lists. 1749 if (StructuredList) 1750 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result); 1751 else { 1752 Result->setSyntacticForm(IList); 1753 SyntacticToSemantic[IList] = Result; 1754 } 1755 1756 return Result; 1757} 1758 1759/// Update the initializer at index @p StructuredIndex within the 1760/// structured initializer list to the value @p expr. 1761void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList, 1762 unsigned &StructuredIndex, 1763 Expr *expr) { 1764 // No structured initializer list to update 1765 if (!StructuredList) 1766 return; 1767 1768 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context, 1769 StructuredIndex, expr)) { 1770 // This initializer overwrites a previous initializer. Warn. 1771 SemaRef.Diag(expr->getSourceRange().getBegin(), 1772 diag::warn_initializer_overrides) 1773 << expr->getSourceRange(); 1774 SemaRef.Diag(PrevInit->getSourceRange().getBegin(), 1775 diag::note_previous_initializer) 1776 << /*FIXME:has side effects=*/0 1777 << PrevInit->getSourceRange(); 1778 } 1779 1780 ++StructuredIndex; 1781} 1782 1783/// Check that the given Index expression is a valid array designator 1784/// value. This is essentailly just a wrapper around 1785/// VerifyIntegerConstantExpression that also checks for negative values 1786/// and produces a reasonable diagnostic if there is a 1787/// failure. Returns true if there was an error, false otherwise. If 1788/// everything went okay, Value will receive the value of the constant 1789/// expression. 1790static bool 1791CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) { 1792 SourceLocation Loc = Index->getSourceRange().getBegin(); 1793 1794 // Make sure this is an integer constant expression. 1795 if (S.VerifyIntegerConstantExpression(Index, &Value)) 1796 return true; 1797 1798 if (Value.isSigned() && Value.isNegative()) 1799 return S.Diag(Loc, diag::err_array_designator_negative) 1800 << Value.toString(10) << Index->getSourceRange(); 1801 1802 Value.setIsUnsigned(true); 1803 return false; 1804} 1805 1806Sema::OwningExprResult Sema::ActOnDesignatedInitializer(Designation &Desig, 1807 SourceLocation Loc, 1808 bool GNUSyntax, 1809 OwningExprResult Init) { 1810 typedef DesignatedInitExpr::Designator ASTDesignator; 1811 1812 bool Invalid = false; 1813 llvm::SmallVector<ASTDesignator, 32> Designators; 1814 llvm::SmallVector<Expr *, 32> InitExpressions; 1815 1816 // Build designators and check array designator expressions. 1817 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) { 1818 const Designator &D = Desig.getDesignator(Idx); 1819 switch (D.getKind()) { 1820 case Designator::FieldDesignator: 1821 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(), 1822 D.getFieldLoc())); 1823 break; 1824 1825 case Designator::ArrayDesignator: { 1826 Expr *Index = static_cast<Expr *>(D.getArrayIndex()); 1827 llvm::APSInt IndexValue; 1828 if (!Index->isTypeDependent() && 1829 !Index->isValueDependent() && 1830 CheckArrayDesignatorExpr(*this, Index, IndexValue)) 1831 Invalid = true; 1832 else { 1833 Designators.push_back(ASTDesignator(InitExpressions.size(), 1834 D.getLBracketLoc(), 1835 D.getRBracketLoc())); 1836 InitExpressions.push_back(Index); 1837 } 1838 break; 1839 } 1840 1841 case Designator::ArrayRangeDesignator: { 1842 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart()); 1843 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd()); 1844 llvm::APSInt StartValue; 1845 llvm::APSInt EndValue; 1846 bool StartDependent = StartIndex->isTypeDependent() || 1847 StartIndex->isValueDependent(); 1848 bool EndDependent = EndIndex->isTypeDependent() || 1849 EndIndex->isValueDependent(); 1850 if ((!StartDependent && 1851 CheckArrayDesignatorExpr(*this, StartIndex, StartValue)) || 1852 (!EndDependent && 1853 CheckArrayDesignatorExpr(*this, EndIndex, EndValue))) 1854 Invalid = true; 1855 else { 1856 // Make sure we're comparing values with the same bit width. 1857 if (StartDependent || EndDependent) { 1858 // Nothing to compute. 1859 } else if (StartValue.getBitWidth() > EndValue.getBitWidth()) 1860 EndValue.extend(StartValue.getBitWidth()); 1861 else if (StartValue.getBitWidth() < EndValue.getBitWidth()) 1862 StartValue.extend(EndValue.getBitWidth()); 1863 1864 if (!StartDependent && !EndDependent && EndValue < StartValue) { 1865 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range) 1866 << StartValue.toString(10) << EndValue.toString(10) 1867 << StartIndex->getSourceRange() << EndIndex->getSourceRange(); 1868 Invalid = true; 1869 } else { 1870 Designators.push_back(ASTDesignator(InitExpressions.size(), 1871 D.getLBracketLoc(), 1872 D.getEllipsisLoc(), 1873 D.getRBracketLoc())); 1874 InitExpressions.push_back(StartIndex); 1875 InitExpressions.push_back(EndIndex); 1876 } 1877 } 1878 break; 1879 } 1880 } 1881 } 1882 1883 if (Invalid || Init.isInvalid()) 1884 return ExprError(); 1885 1886 // Clear out the expressions within the designation. 1887 Desig.ClearExprs(*this); 1888 1889 DesignatedInitExpr *DIE 1890 = DesignatedInitExpr::Create(Context, 1891 Designators.data(), Designators.size(), 1892 InitExpressions.data(), InitExpressions.size(), 1893 Loc, GNUSyntax, Init.takeAs<Expr>()); 1894 return Owned(DIE); 1895} 1896 1897bool Sema::CheckInitList(const InitializedEntity &Entity, 1898 InitListExpr *&InitList, QualType &DeclType) { 1899 InitListChecker CheckInitList(*this, Entity, InitList, DeclType); 1900 if (!CheckInitList.HadError()) 1901 InitList = CheckInitList.getFullyStructuredList(); 1902 1903 return CheckInitList.HadError(); 1904} 1905 1906//===----------------------------------------------------------------------===// 1907// Initialization entity 1908//===----------------------------------------------------------------------===// 1909 1910InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index, 1911 const InitializedEntity &Parent) 1912 : Parent(&Parent), Index(Index) 1913{ 1914 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) { 1915 Kind = EK_ArrayElement; 1916 Type = AT->getElementType(); 1917 } else { 1918 Kind = EK_VectorElement; 1919 Type = Parent.getType()->getAs<VectorType>()->getElementType(); 1920 } 1921} 1922 1923InitializedEntity InitializedEntity::InitializeBase(ASTContext &Context, 1924 CXXBaseSpecifier *Base, 1925 bool IsInheritedVirtualBase) 1926{ 1927 InitializedEntity Result; 1928 Result.Kind = EK_Base; 1929 Result.Base = reinterpret_cast<uintptr_t>(Base); 1930 if (IsInheritedVirtualBase) 1931 Result.Base |= 0x01; 1932 1933 Result.Type = Base->getType(); 1934 return Result; 1935} 1936 1937DeclarationName InitializedEntity::getName() const { 1938 switch (getKind()) { 1939 case EK_Parameter: 1940 if (!VariableOrMember) 1941 return DeclarationName(); 1942 // Fall through 1943 1944 case EK_Variable: 1945 case EK_Member: 1946 return VariableOrMember->getDeclName(); 1947 1948 case EK_Result: 1949 case EK_Exception: 1950 case EK_New: 1951 case EK_Temporary: 1952 case EK_Base: 1953 case EK_ArrayElement: 1954 case EK_VectorElement: 1955 return DeclarationName(); 1956 } 1957 1958 // Silence GCC warning 1959 return DeclarationName(); 1960} 1961 1962DeclaratorDecl *InitializedEntity::getDecl() const { 1963 switch (getKind()) { 1964 case EK_Variable: 1965 case EK_Parameter: 1966 case EK_Member: 1967 return VariableOrMember; 1968 1969 case EK_Result: 1970 case EK_Exception: 1971 case EK_New: 1972 case EK_Temporary: 1973 case EK_Base: 1974 case EK_ArrayElement: 1975 case EK_VectorElement: 1976 return 0; 1977 } 1978 1979 // Silence GCC warning 1980 return 0; 1981} 1982 1983//===----------------------------------------------------------------------===// 1984// Initialization sequence 1985//===----------------------------------------------------------------------===// 1986 1987void InitializationSequence::Step::Destroy() { 1988 switch (Kind) { 1989 case SK_ResolveAddressOfOverloadedFunction: 1990 case SK_CastDerivedToBaseRValue: 1991 case SK_CastDerivedToBaseLValue: 1992 case SK_BindReference: 1993 case SK_BindReferenceToTemporary: 1994 case SK_ExtraneousCopyToTemporary: 1995 case SK_UserConversion: 1996 case SK_QualificationConversionRValue: 1997 case SK_QualificationConversionLValue: 1998 case SK_ListInitialization: 1999 case SK_ConstructorInitialization: 2000 case SK_ZeroInitialization: 2001 case SK_CAssignment: 2002 case SK_StringInit: 2003 break; 2004 2005 case SK_ConversionSequence: 2006 delete ICS; 2007 } 2008} 2009 2010bool InitializationSequence::isDirectReferenceBinding() const { 2011 return getKind() == ReferenceBinding && Steps.back().Kind == SK_BindReference; 2012} 2013 2014bool InitializationSequence::isAmbiguous() const { 2015 if (getKind() != FailedSequence) 2016 return false; 2017 2018 switch (getFailureKind()) { 2019 case FK_TooManyInitsForReference: 2020 case FK_ArrayNeedsInitList: 2021 case FK_ArrayNeedsInitListOrStringLiteral: 2022 case FK_AddressOfOverloadFailed: // FIXME: Could do better 2023 case FK_NonConstLValueReferenceBindingToTemporary: 2024 case FK_NonConstLValueReferenceBindingToUnrelated: 2025 case FK_RValueReferenceBindingToLValue: 2026 case FK_ReferenceInitDropsQualifiers: 2027 case FK_ReferenceInitFailed: 2028 case FK_ConversionFailed: 2029 case FK_TooManyInitsForScalar: 2030 case FK_ReferenceBindingToInitList: 2031 case FK_InitListBadDestinationType: 2032 case FK_DefaultInitOfConst: 2033 return false; 2034 2035 case FK_ReferenceInitOverloadFailed: 2036 case FK_UserConversionOverloadFailed: 2037 case FK_ConstructorOverloadFailed: 2038 return FailedOverloadResult == OR_Ambiguous; 2039 } 2040 2041 return false; 2042} 2043 2044bool InitializationSequence::isConstructorInitialization() const { 2045 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization; 2046} 2047 2048void InitializationSequence::AddAddressOverloadResolutionStep( 2049 FunctionDecl *Function, 2050 DeclAccessPair Found) { 2051 Step S; 2052 S.Kind = SK_ResolveAddressOfOverloadedFunction; 2053 S.Type = Function->getType(); 2054 S.Function.Function = Function; 2055 S.Function.FoundDecl = Found; 2056 Steps.push_back(S); 2057} 2058 2059void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType, 2060 bool IsLValue) { 2061 Step S; 2062 S.Kind = IsLValue? SK_CastDerivedToBaseLValue : SK_CastDerivedToBaseRValue; 2063 S.Type = BaseType; 2064 Steps.push_back(S); 2065} 2066 2067void InitializationSequence::AddReferenceBindingStep(QualType T, 2068 bool BindingTemporary) { 2069 Step S; 2070 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference; 2071 S.Type = T; 2072 Steps.push_back(S); 2073} 2074 2075void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) { 2076 Step S; 2077 S.Kind = SK_ExtraneousCopyToTemporary; 2078 S.Type = T; 2079 Steps.push_back(S); 2080} 2081 2082void InitializationSequence::AddUserConversionStep(FunctionDecl *Function, 2083 DeclAccessPair FoundDecl, 2084 QualType T) { 2085 Step S; 2086 S.Kind = SK_UserConversion; 2087 S.Type = T; 2088 S.Function.Function = Function; 2089 S.Function.FoundDecl = FoundDecl; 2090 Steps.push_back(S); 2091} 2092 2093void InitializationSequence::AddQualificationConversionStep(QualType Ty, 2094 bool IsLValue) { 2095 Step S; 2096 S.Kind = IsLValue? SK_QualificationConversionLValue 2097 : SK_QualificationConversionRValue; 2098 S.Type = Ty; 2099 Steps.push_back(S); 2100} 2101 2102void InitializationSequence::AddConversionSequenceStep( 2103 const ImplicitConversionSequence &ICS, 2104 QualType T) { 2105 Step S; 2106 S.Kind = SK_ConversionSequence; 2107 S.Type = T; 2108 S.ICS = new ImplicitConversionSequence(ICS); 2109 Steps.push_back(S); 2110} 2111 2112void InitializationSequence::AddListInitializationStep(QualType T) { 2113 Step S; 2114 S.Kind = SK_ListInitialization; 2115 S.Type = T; 2116 Steps.push_back(S); 2117} 2118 2119void 2120InitializationSequence::AddConstructorInitializationStep( 2121 CXXConstructorDecl *Constructor, 2122 AccessSpecifier Access, 2123 QualType T) { 2124 Step S; 2125 S.Kind = SK_ConstructorInitialization; 2126 S.Type = T; 2127 S.Function.Function = Constructor; 2128 S.Function.FoundDecl = DeclAccessPair::make(Constructor, Access); 2129 Steps.push_back(S); 2130} 2131 2132void InitializationSequence::AddZeroInitializationStep(QualType T) { 2133 Step S; 2134 S.Kind = SK_ZeroInitialization; 2135 S.Type = T; 2136 Steps.push_back(S); 2137} 2138 2139void InitializationSequence::AddCAssignmentStep(QualType T) { 2140 Step S; 2141 S.Kind = SK_CAssignment; 2142 S.Type = T; 2143 Steps.push_back(S); 2144} 2145 2146void InitializationSequence::AddStringInitStep(QualType T) { 2147 Step S; 2148 S.Kind = SK_StringInit; 2149 S.Type = T; 2150 Steps.push_back(S); 2151} 2152 2153void InitializationSequence::SetOverloadFailure(FailureKind Failure, 2154 OverloadingResult Result) { 2155 SequenceKind = FailedSequence; 2156 this->Failure = Failure; 2157 this->FailedOverloadResult = Result; 2158} 2159 2160//===----------------------------------------------------------------------===// 2161// Attempt initialization 2162//===----------------------------------------------------------------------===// 2163 2164/// \brief Attempt list initialization (C++0x [dcl.init.list]) 2165static void TryListInitialization(Sema &S, 2166 const InitializedEntity &Entity, 2167 const InitializationKind &Kind, 2168 InitListExpr *InitList, 2169 InitializationSequence &Sequence) { 2170 // FIXME: We only perform rudimentary checking of list 2171 // initializations at this point, then assume that any list 2172 // initialization of an array, aggregate, or scalar will be 2173 // well-formed. We we actually "perform" list initialization, we'll 2174 // do all of the necessary checking. C++0x initializer lists will 2175 // force us to perform more checking here. 2176 Sequence.setSequenceKind(InitializationSequence::ListInitialization); 2177 2178 QualType DestType = Entity.getType(); 2179 2180 // C++ [dcl.init]p13: 2181 // If T is a scalar type, then a declaration of the form 2182 // 2183 // T x = { a }; 2184 // 2185 // is equivalent to 2186 // 2187 // T x = a; 2188 if (DestType->isScalarType()) { 2189 if (InitList->getNumInits() > 1 && S.getLangOptions().CPlusPlus) { 2190 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar); 2191 return; 2192 } 2193 2194 // Assume scalar initialization from a single value works. 2195 } else if (DestType->isAggregateType()) { 2196 // Assume aggregate initialization works. 2197 } else if (DestType->isVectorType()) { 2198 // Assume vector initialization works. 2199 } else if (DestType->isReferenceType()) { 2200 // FIXME: C++0x defines behavior for this. 2201 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList); 2202 return; 2203 } else if (DestType->isRecordType()) { 2204 // FIXME: C++0x defines behavior for this 2205 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType); 2206 } 2207 2208 // Add a general "list initialization" step. 2209 Sequence.AddListInitializationStep(DestType); 2210} 2211 2212/// \brief Try a reference initialization that involves calling a conversion 2213/// function. 2214/// 2215/// FIXME: look intos DRs 656, 896 2216static OverloadingResult TryRefInitWithConversionFunction(Sema &S, 2217 const InitializedEntity &Entity, 2218 const InitializationKind &Kind, 2219 Expr *Initializer, 2220 bool AllowRValues, 2221 InitializationSequence &Sequence) { 2222 QualType DestType = Entity.getType(); 2223 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 2224 QualType T1 = cv1T1.getUnqualifiedType(); 2225 QualType cv2T2 = Initializer->getType(); 2226 QualType T2 = cv2T2.getUnqualifiedType(); 2227 2228 bool DerivedToBase; 2229 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(), 2230 T1, T2, DerivedToBase) && 2231 "Must have incompatible references when binding via conversion"); 2232 (void)DerivedToBase; 2233 2234 // Build the candidate set directly in the initialization sequence 2235 // structure, so that it will persist if we fail. 2236 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2237 CandidateSet.clear(); 2238 2239 // Determine whether we are allowed to call explicit constructors or 2240 // explicit conversion operators. 2241 bool AllowExplicit = Kind.getKind() == InitializationKind::IK_Direct; 2242 2243 const RecordType *T1RecordType = 0; 2244 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>())) { 2245 // The type we're converting to is a class type. Enumerate its constructors 2246 // to see if there is a suitable conversion. 2247 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl()); 2248 2249 DeclarationName ConstructorName 2250 = S.Context.DeclarationNames.getCXXConstructorName( 2251 S.Context.getCanonicalType(T1).getUnqualifiedType()); 2252 DeclContext::lookup_iterator Con, ConEnd; 2253 for (llvm::tie(Con, ConEnd) = T1RecordDecl->lookup(ConstructorName); 2254 Con != ConEnd; ++Con) { 2255 NamedDecl *D = *Con; 2256 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2257 2258 // Find the constructor (which may be a template). 2259 CXXConstructorDecl *Constructor = 0; 2260 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 2261 if (ConstructorTmpl) 2262 Constructor = cast<CXXConstructorDecl>( 2263 ConstructorTmpl->getTemplatedDecl()); 2264 else 2265 Constructor = cast<CXXConstructorDecl>(D); 2266 2267 if (!Constructor->isInvalidDecl() && 2268 Constructor->isConvertingConstructor(AllowExplicit)) { 2269 if (ConstructorTmpl) 2270 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2271 /*ExplicitArgs*/ 0, 2272 &Initializer, 1, CandidateSet); 2273 else 2274 S.AddOverloadCandidate(Constructor, FoundDecl, 2275 &Initializer, 1, CandidateSet); 2276 } 2277 } 2278 } 2279 2280 if (const RecordType *T2RecordType = T2->getAs<RecordType>()) { 2281 // The type we're converting from is a class type, enumerate its conversion 2282 // functions. 2283 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl()); 2284 2285 // Determine the type we are converting to. If we are allowed to 2286 // convert to an rvalue, take the type that the destination type 2287 // refers to. 2288 QualType ToType = AllowRValues? cv1T1 : DestType; 2289 2290 const UnresolvedSetImpl *Conversions 2291 = T2RecordDecl->getVisibleConversionFunctions(); 2292 for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), 2293 E = Conversions->end(); I != E; ++I) { 2294 NamedDecl *D = *I; 2295 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 2296 if (isa<UsingShadowDecl>(D)) 2297 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2298 2299 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 2300 CXXConversionDecl *Conv; 2301 if (ConvTemplate) 2302 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2303 else 2304 Conv = cast<CXXConversionDecl>(*I); 2305 2306 // If the conversion function doesn't return a reference type, 2307 // it can't be considered for this conversion unless we're allowed to 2308 // consider rvalues. 2309 // FIXME: Do we need to make sure that we only consider conversion 2310 // candidates with reference-compatible results? That might be needed to 2311 // break recursion. 2312 if ((AllowExplicit || !Conv->isExplicit()) && 2313 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){ 2314 if (ConvTemplate) 2315 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 2316 ActingDC, Initializer, 2317 ToType, CandidateSet); 2318 else 2319 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 2320 Initializer, ToType, CandidateSet); 2321 } 2322 } 2323 } 2324 2325 SourceLocation DeclLoc = Initializer->getLocStart(); 2326 2327 // Perform overload resolution. If it fails, return the failed result. 2328 OverloadCandidateSet::iterator Best; 2329 if (OverloadingResult Result 2330 = S.BestViableFunction(CandidateSet, DeclLoc, Best)) 2331 return Result; 2332 2333 FunctionDecl *Function = Best->Function; 2334 2335 // Compute the returned type of the conversion. 2336 if (isa<CXXConversionDecl>(Function)) 2337 T2 = Function->getResultType(); 2338 else 2339 T2 = cv1T1; 2340 2341 // Add the user-defined conversion step. 2342 Sequence.AddUserConversionStep(Function, Best->FoundDecl, 2343 T2.getNonReferenceType()); 2344 2345 // Determine whether we need to perform derived-to-base or 2346 // cv-qualification adjustments. 2347 bool NewDerivedToBase = false; 2348 Sema::ReferenceCompareResult NewRefRelationship 2349 = S.CompareReferenceRelationship(DeclLoc, T1, T2.getNonReferenceType(), 2350 NewDerivedToBase); 2351 if (NewRefRelationship == Sema::Ref_Incompatible) { 2352 // If the type we've converted to is not reference-related to the 2353 // type we're looking for, then there is another conversion step 2354 // we need to perform to produce a temporary of the right type 2355 // that we'll be binding to. 2356 ImplicitConversionSequence ICS; 2357 ICS.setStandard(); 2358 ICS.Standard = Best->FinalConversion; 2359 T2 = ICS.Standard.getToType(2); 2360 Sequence.AddConversionSequenceStep(ICS, T2); 2361 } else if (NewDerivedToBase) 2362 Sequence.AddDerivedToBaseCastStep( 2363 S.Context.getQualifiedType(T1, 2364 T2.getNonReferenceType().getQualifiers()), 2365 /*isLValue=*/true); 2366 2367 if (cv1T1.getQualifiers() != T2.getNonReferenceType().getQualifiers()) 2368 Sequence.AddQualificationConversionStep(cv1T1, T2->isReferenceType()); 2369 2370 Sequence.AddReferenceBindingStep(cv1T1, !T2->isReferenceType()); 2371 return OR_Success; 2372} 2373 2374/// \brief Attempt reference initialization (C++0x [dcl.init.list]) 2375static void TryReferenceInitialization(Sema &S, 2376 const InitializedEntity &Entity, 2377 const InitializationKind &Kind, 2378 Expr *Initializer, 2379 InitializationSequence &Sequence) { 2380 Sequence.setSequenceKind(InitializationSequence::ReferenceBinding); 2381 2382 QualType DestType = Entity.getType(); 2383 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 2384 Qualifiers T1Quals; 2385 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); 2386 QualType cv2T2 = Initializer->getType(); 2387 Qualifiers T2Quals; 2388 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); 2389 SourceLocation DeclLoc = Initializer->getLocStart(); 2390 2391 // If the initializer is the address of an overloaded function, try 2392 // to resolve the overloaded function. If all goes well, T2 is the 2393 // type of the resulting function. 2394 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 2395 DeclAccessPair Found; 2396 FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Initializer, 2397 T1, 2398 false, 2399 Found); 2400 if (!Fn) { 2401 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 2402 return; 2403 } 2404 2405 Sequence.AddAddressOverloadResolutionStep(Fn, Found); 2406 cv2T2 = Fn->getType(); 2407 T2 = cv2T2.getUnqualifiedType(); 2408 } 2409 2410 // Compute some basic properties of the types and the initializer. 2411 bool isLValueRef = DestType->isLValueReferenceType(); 2412 bool isRValueRef = !isLValueRef; 2413 bool DerivedToBase = false; 2414 Expr::isLvalueResult InitLvalue = Initializer->isLvalue(S.Context); 2415 Sema::ReferenceCompareResult RefRelationship 2416 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase); 2417 2418 // C++0x [dcl.init.ref]p5: 2419 // A reference to type "cv1 T1" is initialized by an expression of type 2420 // "cv2 T2" as follows: 2421 // 2422 // - If the reference is an lvalue reference and the initializer 2423 // expression 2424 OverloadingResult ConvOvlResult = OR_Success; 2425 if (isLValueRef) { 2426 if (InitLvalue == Expr::LV_Valid && 2427 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 2428 // - is an lvalue (but is not a bit-field), and "cv1 T1" is 2429 // reference-compatible with "cv2 T2," or 2430 // 2431 // Per C++ [over.best.ics]p2, we don't diagnose whether the lvalue is a 2432 // bit-field when we're determining whether the reference initialization 2433 // can occur. However, we do pay attention to whether it is a bit-field 2434 // to decide whether we're actually binding to a temporary created from 2435 // the bit-field. 2436 if (DerivedToBase) 2437 Sequence.AddDerivedToBaseCastStep( 2438 S.Context.getQualifiedType(T1, T2Quals), 2439 /*isLValue=*/true); 2440 if (T1Quals != T2Quals) 2441 Sequence.AddQualificationConversionStep(cv1T1, /*IsLValue=*/true); 2442 bool BindingTemporary = T1Quals.hasConst() && !T1Quals.hasVolatile() && 2443 (Initializer->getBitField() || Initializer->refersToVectorElement()); 2444 Sequence.AddReferenceBindingStep(cv1T1, BindingTemporary); 2445 return; 2446 } 2447 2448 // - has a class type (i.e., T2 is a class type), where T1 is not 2449 // reference-related to T2, and can be implicitly converted to an 2450 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible 2451 // with "cv3 T3" (this conversion is selected by enumerating the 2452 // applicable conversion functions (13.3.1.6) and choosing the best 2453 // one through overload resolution (13.3)), 2454 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType()) { 2455 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, Kind, 2456 Initializer, 2457 /*AllowRValues=*/false, 2458 Sequence); 2459 if (ConvOvlResult == OR_Success) 2460 return; 2461 if (ConvOvlResult != OR_No_Viable_Function) { 2462 Sequence.SetOverloadFailure( 2463 InitializationSequence::FK_ReferenceInitOverloadFailed, 2464 ConvOvlResult); 2465 } 2466 } 2467 } 2468 2469 // - Otherwise, the reference shall be an lvalue reference to a 2470 // non-volatile const type (i.e., cv1 shall be const), or the reference 2471 // shall be an rvalue reference and the initializer expression shall 2472 // be an rvalue. 2473 if (!((isLValueRef && T1Quals.hasConst() && !T1Quals.hasVolatile()) || 2474 (isRValueRef && InitLvalue != Expr::LV_Valid))) { 2475 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 2476 Sequence.SetOverloadFailure( 2477 InitializationSequence::FK_ReferenceInitOverloadFailed, 2478 ConvOvlResult); 2479 else if (isLValueRef) 2480 Sequence.SetFailed(InitLvalue == Expr::LV_Valid 2481 ? (RefRelationship == Sema::Ref_Related 2482 ? InitializationSequence::FK_ReferenceInitDropsQualifiers 2483 : InitializationSequence::FK_NonConstLValueReferenceBindingToUnrelated) 2484 : InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); 2485 else 2486 Sequence.SetFailed( 2487 InitializationSequence::FK_RValueReferenceBindingToLValue); 2488 2489 return; 2490 } 2491 2492 // - If T1 and T2 are class types and 2493 if (T1->isRecordType() && T2->isRecordType()) { 2494 // - the initializer expression is an rvalue and "cv1 T1" is 2495 // reference-compatible with "cv2 T2", or 2496 if (InitLvalue != Expr::LV_Valid && 2497 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 2498 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the 2499 // compiler the freedom to perform a copy here or bind to the 2500 // object, while C++0x requires that we bind directly to the 2501 // object. Hence, we always bind to the object without making an 2502 // extra copy. However, in C++03 requires that we check for the 2503 // presence of a suitable copy constructor: 2504 // 2505 // The constructor that would be used to make the copy shall 2506 // be callable whether or not the copy is actually done. 2507 if (!S.getLangOptions().CPlusPlus0x) 2508 Sequence.AddExtraneousCopyToTemporary(cv2T2); 2509 2510 if (DerivedToBase) 2511 Sequence.AddDerivedToBaseCastStep( 2512 S.Context.getQualifiedType(T1, T2Quals), 2513 /*isLValue=*/false); 2514 if (T1Quals != T2Quals) 2515 Sequence.AddQualificationConversionStep(cv1T1, /*IsLValue=*/false); 2516 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 2517 return; 2518 } 2519 2520 // - T1 is not reference-related to T2 and the initializer expression 2521 // can be implicitly converted to an rvalue of type "cv3 T3" (this 2522 // conversion is selected by enumerating the applicable conversion 2523 // functions (13.3.1.6) and choosing the best one through overload 2524 // resolution (13.3)), 2525 if (RefRelationship == Sema::Ref_Incompatible) { 2526 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, 2527 Kind, Initializer, 2528 /*AllowRValues=*/true, 2529 Sequence); 2530 if (ConvOvlResult) 2531 Sequence.SetOverloadFailure( 2532 InitializationSequence::FK_ReferenceInitOverloadFailed, 2533 ConvOvlResult); 2534 2535 return; 2536 } 2537 2538 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 2539 return; 2540 } 2541 2542 // - If the initializer expression is an rvalue, with T2 an array type, 2543 // and "cv1 T1" is reference-compatible with "cv2 T2," the reference 2544 // is bound to the object represented by the rvalue (see 3.10). 2545 // FIXME: How can an array type be reference-compatible with anything? 2546 // Don't we mean the element types of T1 and T2? 2547 2548 // - Otherwise, a temporary of type “cv1 T1” is created and initialized 2549 // from the initializer expression using the rules for a non-reference 2550 // copy initialization (8.5). The reference is then bound to the 2551 // temporary. [...] 2552 // Determine whether we are allowed to call explicit constructors or 2553 // explicit conversion operators. 2554 bool AllowExplicit = (Kind.getKind() == InitializationKind::IK_Direct); 2555 ImplicitConversionSequence ICS 2556 = S.TryImplicitConversion(Initializer, cv1T1, 2557 /*SuppressUserConversions=*/false, AllowExplicit, 2558 /*FIXME:InOverloadResolution=*/false); 2559 2560 if (ICS.isBad()) { 2561 // FIXME: Use the conversion function set stored in ICS to turn 2562 // this into an overloading ambiguity diagnostic. However, we need 2563 // to keep that set as an OverloadCandidateSet rather than as some 2564 // other kind of set. 2565 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 2566 Sequence.SetOverloadFailure( 2567 InitializationSequence::FK_ReferenceInitOverloadFailed, 2568 ConvOvlResult); 2569 else 2570 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed); 2571 return; 2572 } 2573 2574 // [...] If T1 is reference-related to T2, cv1 must be the 2575 // same cv-qualification as, or greater cv-qualification 2576 // than, cv2; otherwise, the program is ill-formed. 2577 unsigned T1CVRQuals = T1Quals.getCVRQualifiers(); 2578 unsigned T2CVRQuals = T2Quals.getCVRQualifiers(); 2579 if (RefRelationship == Sema::Ref_Related && 2580 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) { 2581 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 2582 return; 2583 } 2584 2585 // Perform the actual conversion. 2586 Sequence.AddConversionSequenceStep(ICS, cv1T1); 2587 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 2588 return; 2589} 2590 2591/// \brief Attempt character array initialization from a string literal 2592/// (C++ [dcl.init.string], C99 6.7.8). 2593static void TryStringLiteralInitialization(Sema &S, 2594 const InitializedEntity &Entity, 2595 const InitializationKind &Kind, 2596 Expr *Initializer, 2597 InitializationSequence &Sequence) { 2598 Sequence.setSequenceKind(InitializationSequence::StringInit); 2599 Sequence.AddStringInitStep(Entity.getType()); 2600} 2601 2602/// \brief Attempt initialization by constructor (C++ [dcl.init]), which 2603/// enumerates the constructors of the initialized entity and performs overload 2604/// resolution to select the best. 2605static void TryConstructorInitialization(Sema &S, 2606 const InitializedEntity &Entity, 2607 const InitializationKind &Kind, 2608 Expr **Args, unsigned NumArgs, 2609 QualType DestType, 2610 InitializationSequence &Sequence) { 2611 Sequence.setSequenceKind(InitializationSequence::ConstructorInitialization); 2612 2613 // Build the candidate set directly in the initialization sequence 2614 // structure, so that it will persist if we fail. 2615 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2616 CandidateSet.clear(); 2617 2618 // Determine whether we are allowed to call explicit constructors or 2619 // explicit conversion operators. 2620 bool AllowExplicit = (Kind.getKind() == InitializationKind::IK_Direct || 2621 Kind.getKind() == InitializationKind::IK_Value || 2622 Kind.getKind() == InitializationKind::IK_Default); 2623 2624 // The type we're converting to is a class type. Enumerate its constructors 2625 // to see if one is suitable. 2626 const RecordType *DestRecordType = DestType->getAs<RecordType>(); 2627 assert(DestRecordType && "Constructor initialization requires record type"); 2628 CXXRecordDecl *DestRecordDecl 2629 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 2630 2631 DeclarationName ConstructorName 2632 = S.Context.DeclarationNames.getCXXConstructorName( 2633 S.Context.getCanonicalType(DestType).getUnqualifiedType()); 2634 DeclContext::lookup_iterator Con, ConEnd; 2635 for (llvm::tie(Con, ConEnd) = DestRecordDecl->lookup(ConstructorName); 2636 Con != ConEnd; ++Con) { 2637 NamedDecl *D = *Con; 2638 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2639 2640 // Find the constructor (which may be a template). 2641 CXXConstructorDecl *Constructor = 0; 2642 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 2643 if (ConstructorTmpl) 2644 Constructor = cast<CXXConstructorDecl>( 2645 ConstructorTmpl->getTemplatedDecl()); 2646 else 2647 Constructor = cast<CXXConstructorDecl>(D); 2648 2649 if (!Constructor->isInvalidDecl() && 2650 (AllowExplicit || !Constructor->isExplicit())) { 2651 if (ConstructorTmpl) 2652 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2653 /*ExplicitArgs*/ 0, 2654 Args, NumArgs, CandidateSet); 2655 else 2656 S.AddOverloadCandidate(Constructor, FoundDecl, 2657 Args, NumArgs, CandidateSet); 2658 } 2659 } 2660 2661 SourceLocation DeclLoc = Kind.getLocation(); 2662 2663 // Perform overload resolution. If it fails, return the failed result. 2664 OverloadCandidateSet::iterator Best; 2665 if (OverloadingResult Result 2666 = S.BestViableFunction(CandidateSet, DeclLoc, Best)) { 2667 Sequence.SetOverloadFailure( 2668 InitializationSequence::FK_ConstructorOverloadFailed, 2669 Result); 2670 return; 2671 } 2672 2673 // C++0x [dcl.init]p6: 2674 // If a program calls for the default initialization of an object 2675 // of a const-qualified type T, T shall be a class type with a 2676 // user-provided default constructor. 2677 if (Kind.getKind() == InitializationKind::IK_Default && 2678 Entity.getType().isConstQualified() && 2679 cast<CXXConstructorDecl>(Best->Function)->isImplicit()) { 2680 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 2681 return; 2682 } 2683 2684 // Add the constructor initialization step. Any cv-qualification conversion is 2685 // subsumed by the initialization. 2686 Sequence.AddConstructorInitializationStep( 2687 cast<CXXConstructorDecl>(Best->Function), 2688 Best->FoundDecl.getAccess(), 2689 DestType); 2690} 2691 2692/// \brief Attempt value initialization (C++ [dcl.init]p7). 2693static void TryValueInitialization(Sema &S, 2694 const InitializedEntity &Entity, 2695 const InitializationKind &Kind, 2696 InitializationSequence &Sequence) { 2697 // C++ [dcl.init]p5: 2698 // 2699 // To value-initialize an object of type T means: 2700 QualType T = Entity.getType(); 2701 2702 // -- if T is an array type, then each element is value-initialized; 2703 while (const ArrayType *AT = S.Context.getAsArrayType(T)) 2704 T = AT->getElementType(); 2705 2706 if (const RecordType *RT = T->getAs<RecordType>()) { 2707 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 2708 // -- if T is a class type (clause 9) with a user-declared 2709 // constructor (12.1), then the default constructor for T is 2710 // called (and the initialization is ill-formed if T has no 2711 // accessible default constructor); 2712 // 2713 // FIXME: we really want to refer to a single subobject of the array, 2714 // but Entity doesn't have a way to capture that (yet). 2715 if (ClassDecl->hasUserDeclaredConstructor()) 2716 return TryConstructorInitialization(S, Entity, Kind, 0, 0, T, Sequence); 2717 2718 // -- if T is a (possibly cv-qualified) non-union class type 2719 // without a user-provided constructor, then the object is 2720 // zero-initialized and, if T’s implicitly-declared default 2721 // constructor is non-trivial, that constructor is called. 2722 if ((ClassDecl->getTagKind() == TagDecl::TK_class || 2723 ClassDecl->getTagKind() == TagDecl::TK_struct) && 2724 !ClassDecl->hasTrivialConstructor()) { 2725 Sequence.AddZeroInitializationStep(Entity.getType()); 2726 return TryConstructorInitialization(S, Entity, Kind, 0, 0, T, Sequence); 2727 } 2728 } 2729 } 2730 2731 Sequence.AddZeroInitializationStep(Entity.getType()); 2732 Sequence.setSequenceKind(InitializationSequence::ZeroInitialization); 2733} 2734 2735/// \brief Attempt default initialization (C++ [dcl.init]p6). 2736static void TryDefaultInitialization(Sema &S, 2737 const InitializedEntity &Entity, 2738 const InitializationKind &Kind, 2739 InitializationSequence &Sequence) { 2740 assert(Kind.getKind() == InitializationKind::IK_Default); 2741 2742 // C++ [dcl.init]p6: 2743 // To default-initialize an object of type T means: 2744 // - if T is an array type, each element is default-initialized; 2745 QualType DestType = Entity.getType(); 2746 while (const ArrayType *Array = S.Context.getAsArrayType(DestType)) 2747 DestType = Array->getElementType(); 2748 2749 // - if T is a (possibly cv-qualified) class type (Clause 9), the default 2750 // constructor for T is called (and the initialization is ill-formed if 2751 // T has no accessible default constructor); 2752 if (DestType->isRecordType() && S.getLangOptions().CPlusPlus) { 2753 return TryConstructorInitialization(S, Entity, Kind, 0, 0, DestType, 2754 Sequence); 2755 } 2756 2757 // - otherwise, no initialization is performed. 2758 Sequence.setSequenceKind(InitializationSequence::NoInitialization); 2759 2760 // If a program calls for the default initialization of an object of 2761 // a const-qualified type T, T shall be a class type with a user-provided 2762 // default constructor. 2763 if (DestType.isConstQualified() && S.getLangOptions().CPlusPlus) 2764 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 2765} 2766 2767/// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]), 2768/// which enumerates all conversion functions and performs overload resolution 2769/// to select the best. 2770static void TryUserDefinedConversion(Sema &S, 2771 const InitializedEntity &Entity, 2772 const InitializationKind &Kind, 2773 Expr *Initializer, 2774 InitializationSequence &Sequence) { 2775 Sequence.setSequenceKind(InitializationSequence::UserDefinedConversion); 2776 2777 QualType DestType = Entity.getType(); 2778 assert(!DestType->isReferenceType() && "References are handled elsewhere"); 2779 QualType SourceType = Initializer->getType(); 2780 assert((DestType->isRecordType() || SourceType->isRecordType()) && 2781 "Must have a class type to perform a user-defined conversion"); 2782 2783 // Build the candidate set directly in the initialization sequence 2784 // structure, so that it will persist if we fail. 2785 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 2786 CandidateSet.clear(); 2787 2788 // Determine whether we are allowed to call explicit constructors or 2789 // explicit conversion operators. 2790 bool AllowExplicit = Kind.getKind() == InitializationKind::IK_Direct; 2791 2792 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) { 2793 // The type we're converting to is a class type. Enumerate its constructors 2794 // to see if there is a suitable conversion. 2795 CXXRecordDecl *DestRecordDecl 2796 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 2797 2798 DeclarationName ConstructorName 2799 = S.Context.DeclarationNames.getCXXConstructorName( 2800 S.Context.getCanonicalType(DestType).getUnqualifiedType()); 2801 DeclContext::lookup_iterator Con, ConEnd; 2802 for (llvm::tie(Con, ConEnd) = DestRecordDecl->lookup(ConstructorName); 2803 Con != ConEnd; ++Con) { 2804 NamedDecl *D = *Con; 2805 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2806 2807 // Find the constructor (which may be a template). 2808 CXXConstructorDecl *Constructor = 0; 2809 FunctionTemplateDecl *ConstructorTmpl 2810 = dyn_cast<FunctionTemplateDecl>(D); 2811 if (ConstructorTmpl) 2812 Constructor = cast<CXXConstructorDecl>( 2813 ConstructorTmpl->getTemplatedDecl()); 2814 else 2815 Constructor = cast<CXXConstructorDecl>(D); 2816 2817 if (!Constructor->isInvalidDecl() && 2818 Constructor->isConvertingConstructor(AllowExplicit)) { 2819 if (ConstructorTmpl) 2820 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2821 /*ExplicitArgs*/ 0, 2822 &Initializer, 1, CandidateSet); 2823 else 2824 S.AddOverloadCandidate(Constructor, FoundDecl, 2825 &Initializer, 1, CandidateSet); 2826 } 2827 } 2828 } 2829 2830 SourceLocation DeclLoc = Initializer->getLocStart(); 2831 2832 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) { 2833 // The type we're converting from is a class type, enumerate its conversion 2834 // functions. 2835 2836 // We can only enumerate the conversion functions for a complete type; if 2837 // the type isn't complete, simply skip this step. 2838 if (!S.RequireCompleteType(DeclLoc, SourceType, 0)) { 2839 CXXRecordDecl *SourceRecordDecl 2840 = cast<CXXRecordDecl>(SourceRecordType->getDecl()); 2841 2842 const UnresolvedSetImpl *Conversions 2843 = SourceRecordDecl->getVisibleConversionFunctions(); 2844 for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), 2845 E = Conversions->end(); 2846 I != E; ++I) { 2847 NamedDecl *D = *I; 2848 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 2849 if (isa<UsingShadowDecl>(D)) 2850 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2851 2852 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 2853 CXXConversionDecl *Conv; 2854 if (ConvTemplate) 2855 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2856 else 2857 Conv = cast<CXXConversionDecl>(D); 2858 2859 if (AllowExplicit || !Conv->isExplicit()) { 2860 if (ConvTemplate) 2861 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 2862 ActingDC, Initializer, DestType, 2863 CandidateSet); 2864 else 2865 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 2866 Initializer, DestType, CandidateSet); 2867 } 2868 } 2869 } 2870 } 2871 2872 // Perform overload resolution. If it fails, return the failed result. 2873 OverloadCandidateSet::iterator Best; 2874 if (OverloadingResult Result 2875 = S.BestViableFunction(CandidateSet, DeclLoc, Best)) { 2876 Sequence.SetOverloadFailure( 2877 InitializationSequence::FK_UserConversionOverloadFailed, 2878 Result); 2879 return; 2880 } 2881 2882 FunctionDecl *Function = Best->Function; 2883 2884 if (isa<CXXConstructorDecl>(Function)) { 2885 // Add the user-defined conversion step. Any cv-qualification conversion is 2886 // subsumed by the initialization. 2887 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType); 2888 return; 2889 } 2890 2891 // Add the user-defined conversion step that calls the conversion function. 2892 QualType ConvType = Function->getResultType().getNonReferenceType(); 2893 if (ConvType->getAs<RecordType>()) { 2894 // If we're converting to a class type, there may be an copy if 2895 // the resulting temporary object (possible to create an object of 2896 // a base class type). That copy is not a separate conversion, so 2897 // we just make a note of the actual destination type (possibly a 2898 // base class of the type returned by the conversion function) and 2899 // let the user-defined conversion step handle the conversion. 2900 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType); 2901 return; 2902 } 2903 2904 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType); 2905 2906 // If the conversion following the call to the conversion function 2907 // is interesting, add it as a separate step. 2908 if (Best->FinalConversion.First || Best->FinalConversion.Second || 2909 Best->FinalConversion.Third) { 2910 ImplicitConversionSequence ICS; 2911 ICS.setStandard(); 2912 ICS.Standard = Best->FinalConversion; 2913 Sequence.AddConversionSequenceStep(ICS, DestType); 2914 } 2915} 2916 2917/// \brief Attempt an implicit conversion (C++ [conv]) converting from one 2918/// non-class type to another. 2919static void TryImplicitConversion(Sema &S, 2920 const InitializedEntity &Entity, 2921 const InitializationKind &Kind, 2922 Expr *Initializer, 2923 InitializationSequence &Sequence) { 2924 ImplicitConversionSequence ICS 2925 = S.TryImplicitConversion(Initializer, Entity.getType(), 2926 /*SuppressUserConversions=*/true, 2927 /*AllowExplicit=*/false, 2928 /*InOverloadResolution=*/false); 2929 2930 if (ICS.isBad()) { 2931 Sequence.SetFailed(InitializationSequence::FK_ConversionFailed); 2932 return; 2933 } 2934 2935 Sequence.AddConversionSequenceStep(ICS, Entity.getType()); 2936} 2937 2938InitializationSequence::InitializationSequence(Sema &S, 2939 const InitializedEntity &Entity, 2940 const InitializationKind &Kind, 2941 Expr **Args, 2942 unsigned NumArgs) 2943 : FailedCandidateSet(Kind.getLocation()) { 2944 ASTContext &Context = S.Context; 2945 2946 // C++0x [dcl.init]p16: 2947 // The semantics of initializers are as follows. The destination type is 2948 // the type of the object or reference being initialized and the source 2949 // type is the type of the initializer expression. The source type is not 2950 // defined when the initializer is a braced-init-list or when it is a 2951 // parenthesized list of expressions. 2952 QualType DestType = Entity.getType(); 2953 2954 if (DestType->isDependentType() || 2955 Expr::hasAnyTypeDependentArguments(Args, NumArgs)) { 2956 SequenceKind = DependentSequence; 2957 return; 2958 } 2959 2960 QualType SourceType; 2961 Expr *Initializer = 0; 2962 if (NumArgs == 1) { 2963 Initializer = Args[0]; 2964 if (!isa<InitListExpr>(Initializer)) 2965 SourceType = Initializer->getType(); 2966 } 2967 2968 // - If the initializer is a braced-init-list, the object is 2969 // list-initialized (8.5.4). 2970 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) { 2971 TryListInitialization(S, Entity, Kind, InitList, *this); 2972 return; 2973 } 2974 2975 // - If the destination type is a reference type, see 8.5.3. 2976 if (DestType->isReferenceType()) { 2977 // C++0x [dcl.init.ref]p1: 2978 // A variable declared to be a T& or T&&, that is, "reference to type T" 2979 // (8.3.2), shall be initialized by an object, or function, of type T or 2980 // by an object that can be converted into a T. 2981 // (Therefore, multiple arguments are not permitted.) 2982 if (NumArgs != 1) 2983 SetFailed(FK_TooManyInitsForReference); 2984 else 2985 TryReferenceInitialization(S, Entity, Kind, Args[0], *this); 2986 return; 2987 } 2988 2989 // - If the destination type is an array of characters, an array of 2990 // char16_t, an array of char32_t, or an array of wchar_t, and the 2991 // initializer is a string literal, see 8.5.2. 2992 if (Initializer && IsStringInit(Initializer, DestType, Context)) { 2993 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this); 2994 return; 2995 } 2996 2997 // - If the initializer is (), the object is value-initialized. 2998 if (Kind.getKind() == InitializationKind::IK_Value || 2999 (Kind.getKind() == InitializationKind::IK_Direct && NumArgs == 0)) { 3000 TryValueInitialization(S, Entity, Kind, *this); 3001 return; 3002 } 3003 3004 // Handle default initialization. 3005 if (Kind.getKind() == InitializationKind::IK_Default){ 3006 TryDefaultInitialization(S, Entity, Kind, *this); 3007 return; 3008 } 3009 3010 // - Otherwise, if the destination type is an array, the program is 3011 // ill-formed. 3012 if (const ArrayType *AT = Context.getAsArrayType(DestType)) { 3013 if (AT->getElementType()->isAnyCharacterType()) 3014 SetFailed(FK_ArrayNeedsInitListOrStringLiteral); 3015 else 3016 SetFailed(FK_ArrayNeedsInitList); 3017 3018 return; 3019 } 3020 3021 // Handle initialization in C 3022 if (!S.getLangOptions().CPlusPlus) { 3023 setSequenceKind(CAssignment); 3024 AddCAssignmentStep(DestType); 3025 return; 3026 } 3027 3028 // - If the destination type is a (possibly cv-qualified) class type: 3029 if (DestType->isRecordType()) { 3030 // - If the initialization is direct-initialization, or if it is 3031 // copy-initialization where the cv-unqualified version of the 3032 // source type is the same class as, or a derived class of, the 3033 // class of the destination, constructors are considered. [...] 3034 if (Kind.getKind() == InitializationKind::IK_Direct || 3035 (Kind.getKind() == InitializationKind::IK_Copy && 3036 (Context.hasSameUnqualifiedType(SourceType, DestType) || 3037 S.IsDerivedFrom(SourceType, DestType)))) 3038 TryConstructorInitialization(S, Entity, Kind, Args, NumArgs, 3039 Entity.getType(), *this); 3040 // - Otherwise (i.e., for the remaining copy-initialization cases), 3041 // user-defined conversion sequences that can convert from the source 3042 // type to the destination type or (when a conversion function is 3043 // used) to a derived class thereof are enumerated as described in 3044 // 13.3.1.4, and the best one is chosen through overload resolution 3045 // (13.3). 3046 else 3047 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 3048 return; 3049 } 3050 3051 if (NumArgs > 1) { 3052 SetFailed(FK_TooManyInitsForScalar); 3053 return; 3054 } 3055 assert(NumArgs == 1 && "Zero-argument case handled above"); 3056 3057 // - Otherwise, if the source type is a (possibly cv-qualified) class 3058 // type, conversion functions are considered. 3059 if (!SourceType.isNull() && SourceType->isRecordType()) { 3060 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 3061 return; 3062 } 3063 3064 // - Otherwise, the initial value of the object being initialized is the 3065 // (possibly converted) value of the initializer expression. Standard 3066 // conversions (Clause 4) will be used, if necessary, to convert the 3067 // initializer expression to the cv-unqualified version of the 3068 // destination type; no user-defined conversions are considered. 3069 setSequenceKind(StandardConversion); 3070 TryImplicitConversion(S, Entity, Kind, Initializer, *this); 3071} 3072 3073InitializationSequence::~InitializationSequence() { 3074 for (llvm::SmallVectorImpl<Step>::iterator Step = Steps.begin(), 3075 StepEnd = Steps.end(); 3076 Step != StepEnd; ++Step) 3077 Step->Destroy(); 3078} 3079 3080//===----------------------------------------------------------------------===// 3081// Perform initialization 3082//===----------------------------------------------------------------------===// 3083static Sema::AssignmentAction 3084getAssignmentAction(const InitializedEntity &Entity) { 3085 switch(Entity.getKind()) { 3086 case InitializedEntity::EK_Variable: 3087 case InitializedEntity::EK_New: 3088 return Sema::AA_Initializing; 3089 3090 case InitializedEntity::EK_Parameter: 3091 if (Entity.getDecl() && 3092 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext())) 3093 return Sema::AA_Sending; 3094 3095 return Sema::AA_Passing; 3096 3097 case InitializedEntity::EK_Result: 3098 return Sema::AA_Returning; 3099 3100 case InitializedEntity::EK_Exception: 3101 case InitializedEntity::EK_Base: 3102 llvm_unreachable("No assignment action for C++-specific initialization"); 3103 break; 3104 3105 case InitializedEntity::EK_Temporary: 3106 // FIXME: Can we tell apart casting vs. converting? 3107 return Sema::AA_Casting; 3108 3109 case InitializedEntity::EK_Member: 3110 case InitializedEntity::EK_ArrayElement: 3111 case InitializedEntity::EK_VectorElement: 3112 return Sema::AA_Initializing; 3113 } 3114 3115 return Sema::AA_Converting; 3116} 3117 3118static bool shouldBindAsTemporary(const InitializedEntity &Entity) { 3119 switch (Entity.getKind()) { 3120 case InitializedEntity::EK_ArrayElement: 3121 case InitializedEntity::EK_Member: 3122 case InitializedEntity::EK_Result: 3123 case InitializedEntity::EK_New: 3124 case InitializedEntity::EK_Variable: 3125 case InitializedEntity::EK_Base: 3126 case InitializedEntity::EK_VectorElement: 3127 case InitializedEntity::EK_Exception: 3128 return false; 3129 3130 case InitializedEntity::EK_Parameter: 3131 case InitializedEntity::EK_Temporary: 3132 return true; 3133 } 3134 3135 llvm_unreachable("missed an InitializedEntity kind?"); 3136} 3137 3138/// \brief Make a (potentially elidable) temporary copy of the object 3139/// provided by the given initializer by calling the appropriate copy 3140/// constructor. 3141/// 3142/// \param S The Sema object used for type-checking. 3143/// 3144/// \param T The type of the temporary object, which must either by 3145/// the type of the initializer expression or a superclass thereof. 3146/// 3147/// \param Enter The entity being initialized. 3148/// 3149/// \param CurInit The initializer expression. 3150/// 3151/// \param IsExtraneousCopy Whether this is an "extraneous" copy that 3152/// is permitted in C++03 (but not C++0x) when binding a reference to 3153/// an rvalue. 3154/// 3155/// \returns An expression that copies the initializer expression into 3156/// a temporary object, or an error expression if a copy could not be 3157/// created. 3158static Sema::OwningExprResult CopyObject(Sema &S, 3159 QualType T, 3160 const InitializedEntity &Entity, 3161 Sema::OwningExprResult CurInit, 3162 bool IsExtraneousCopy) { 3163 // Determine which class type we're copying to. 3164 Expr *CurInitExpr = (Expr *)CurInit.get(); 3165 CXXRecordDecl *Class = 0; 3166 if (const RecordType *Record = T->getAs<RecordType>()) 3167 Class = cast<CXXRecordDecl>(Record->getDecl()); 3168 if (!Class) 3169 return move(CurInit); 3170 3171 // C++0x [class.copy]p34: 3172 // When certain criteria are met, an implementation is allowed to 3173 // omit the copy/move construction of a class object, even if the 3174 // copy/move constructor and/or destructor for the object have 3175 // side effects. [...] 3176 // - when a temporary class object that has not been bound to a 3177 // reference (12.2) would be copied/moved to a class object 3178 // with the same cv-unqualified type, the copy/move operation 3179 // can be omitted by constructing the temporary object 3180 // directly into the target of the omitted copy/move 3181 // 3182 // Note that the other three bullets are handled elsewhere. Copy 3183 // elision for return statements and throw expressions are (FIXME: 3184 // not yet) handled as part of constructor initialization, while 3185 // copy elision for exception handlers is handled by the run-time. 3186 bool Elidable = CurInitExpr->isTemporaryObject() && 3187 S.Context.hasSameUnqualifiedType(T, CurInitExpr->getType()); 3188 SourceLocation Loc; 3189 switch (Entity.getKind()) { 3190 case InitializedEntity::EK_Result: 3191 Loc = Entity.getReturnLoc(); 3192 break; 3193 3194 case InitializedEntity::EK_Exception: 3195 Loc = Entity.getThrowLoc(); 3196 break; 3197 3198 case InitializedEntity::EK_Variable: 3199 Loc = Entity.getDecl()->getLocation(); 3200 break; 3201 3202 case InitializedEntity::EK_ArrayElement: 3203 case InitializedEntity::EK_Member: 3204 case InitializedEntity::EK_Parameter: 3205 case InitializedEntity::EK_Temporary: 3206 case InitializedEntity::EK_New: 3207 case InitializedEntity::EK_Base: 3208 case InitializedEntity::EK_VectorElement: 3209 Loc = CurInitExpr->getLocStart(); 3210 break; 3211 } 3212 3213 // Perform overload resolution using the class's copy constructors. 3214 DeclarationName ConstructorName 3215 = S.Context.DeclarationNames.getCXXConstructorName( 3216 S.Context.getCanonicalType(S.Context.getTypeDeclType(Class))); 3217 DeclContext::lookup_iterator Con, ConEnd; 3218 OverloadCandidateSet CandidateSet(Loc); 3219 for (llvm::tie(Con, ConEnd) = Class->lookup(ConstructorName); 3220 Con != ConEnd; ++Con) { 3221 // Only consider copy constructors. 3222 CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(*Con); 3223 if (!Constructor || Constructor->isInvalidDecl() || 3224 !Constructor->isCopyConstructor() || 3225 !Constructor->isConvertingConstructor(/*AllowExplicit=*/false)) 3226 continue; 3227 3228 DeclAccessPair FoundDecl 3229 = DeclAccessPair::make(Constructor, Constructor->getAccess()); 3230 S.AddOverloadCandidate(Constructor, FoundDecl, 3231 &CurInitExpr, 1, CandidateSet); 3232 } 3233 3234 OverloadCandidateSet::iterator Best; 3235 switch (S.BestViableFunction(CandidateSet, Loc, Best)) { 3236 case OR_Success: 3237 break; 3238 3239 case OR_No_Viable_Function: 3240 S.Diag(Loc, diag::err_temp_copy_no_viable) 3241 << (int)Entity.getKind() << CurInitExpr->getType() 3242 << CurInitExpr->getSourceRange(); 3243 S.PrintOverloadCandidates(CandidateSet, Sema::OCD_AllCandidates, 3244 &CurInitExpr, 1); 3245 return S.ExprError(); 3246 3247 case OR_Ambiguous: 3248 S.Diag(Loc, diag::err_temp_copy_ambiguous) 3249 << (int)Entity.getKind() << CurInitExpr->getType() 3250 << CurInitExpr->getSourceRange(); 3251 S.PrintOverloadCandidates(CandidateSet, Sema::OCD_ViableCandidates, 3252 &CurInitExpr, 1); 3253 return S.ExprError(); 3254 3255 case OR_Deleted: 3256 S.Diag(Loc, diag::err_temp_copy_deleted) 3257 << (int)Entity.getKind() << CurInitExpr->getType() 3258 << CurInitExpr->getSourceRange(); 3259 S.Diag(Best->Function->getLocation(), diag::note_unavailable_here) 3260 << Best->Function->isDeleted(); 3261 return S.ExprError(); 3262 } 3263 3264 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function); 3265 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(S); 3266 CurInit.release(); // Ownership transferred into MultiExprArg, below. 3267 3268 S.CheckConstructorAccess(Loc, Constructor, Entity, 3269 Best->FoundDecl.getAccess()); 3270 3271 if (IsExtraneousCopy) { 3272 // If this is a totally extraneous copy for C++03 reference 3273 // binding purposes, just return the original initialization 3274 // expression. We don't generate an (elided) copy operation here 3275 // because doing so would require us to pass down a flag to avoid 3276 // infinite recursion, where each step adds another extraneous, 3277 // elidable copy. 3278 3279 // Instantiate the default arguments of any extra parameters in 3280 // the selected copy constructor, as if we were going to create a 3281 // proper call to the copy constructor. 3282 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) { 3283 ParmVarDecl *Parm = Constructor->getParamDecl(I); 3284 if (S.RequireCompleteType(Loc, Parm->getType(), 3285 S.PDiag(diag::err_call_incomplete_argument))) 3286 break; 3287 3288 // Build the default argument expression; we don't actually care 3289 // if this succeeds or not, because this routine will complain 3290 // if there was a problem. 3291 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm); 3292 } 3293 3294 return S.Owned(CurInitExpr); 3295 } 3296 3297 // Determine the arguments required to actually perform the 3298 // constructor call (we might have derived-to-base conversions, or 3299 // the copy constructor may have default arguments). 3300 if (S.CompleteConstructorCall(Constructor, 3301 Sema::MultiExprArg(S, 3302 (void **)&CurInitExpr, 3303 1), 3304 Loc, ConstructorArgs)) 3305 return S.ExprError(); 3306 3307 return S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable, 3308 move_arg(ConstructorArgs)); 3309} 3310 3311void InitializationSequence::PrintInitLocationNote(Sema &S, 3312 const InitializedEntity &Entity) { 3313 if (Entity.getKind() == InitializedEntity::EK_Parameter && Entity.getDecl()) { 3314 if (Entity.getDecl()->getLocation().isInvalid()) 3315 return; 3316 3317 if (Entity.getDecl()->getDeclName()) 3318 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here) 3319 << Entity.getDecl()->getDeclName(); 3320 else 3321 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here); 3322 } 3323} 3324 3325Action::OwningExprResult 3326InitializationSequence::Perform(Sema &S, 3327 const InitializedEntity &Entity, 3328 const InitializationKind &Kind, 3329 Action::MultiExprArg Args, 3330 QualType *ResultType) { 3331 if (SequenceKind == FailedSequence) { 3332 unsigned NumArgs = Args.size(); 3333 Diagnose(S, Entity, Kind, (Expr **)Args.release(), NumArgs); 3334 return S.ExprError(); 3335 } 3336 3337 if (SequenceKind == DependentSequence) { 3338 // If the declaration is a non-dependent, incomplete array type 3339 // that has an initializer, then its type will be completed once 3340 // the initializer is instantiated. 3341 if (ResultType && !Entity.getType()->isDependentType() && 3342 Args.size() == 1) { 3343 QualType DeclType = Entity.getType(); 3344 if (const IncompleteArrayType *ArrayT 3345 = S.Context.getAsIncompleteArrayType(DeclType)) { 3346 // FIXME: We don't currently have the ability to accurately 3347 // compute the length of an initializer list without 3348 // performing full type-checking of the initializer list 3349 // (since we have to determine where braces are implicitly 3350 // introduced and such). So, we fall back to making the array 3351 // type a dependently-sized array type with no specified 3352 // bound. 3353 if (isa<InitListExpr>((Expr *)Args.get()[0])) { 3354 SourceRange Brackets; 3355 3356 // Scavange the location of the brackets from the entity, if we can. 3357 if (DeclaratorDecl *DD = Entity.getDecl()) { 3358 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) { 3359 TypeLoc TL = TInfo->getTypeLoc(); 3360 if (IncompleteArrayTypeLoc *ArrayLoc 3361 = dyn_cast<IncompleteArrayTypeLoc>(&TL)) 3362 Brackets = ArrayLoc->getBracketsRange(); 3363 } 3364 } 3365 3366 *ResultType 3367 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(), 3368 /*NumElts=*/0, 3369 ArrayT->getSizeModifier(), 3370 ArrayT->getIndexTypeCVRQualifiers(), 3371 Brackets); 3372 } 3373 3374 } 3375 } 3376 3377 if (Kind.getKind() == InitializationKind::IK_Copy || Kind.isExplicitCast()) 3378 return Sema::OwningExprResult(S, Args.release()[0]); 3379 3380 if (Args.size() == 0) 3381 return S.Owned((Expr *)0); 3382 3383 unsigned NumArgs = Args.size(); 3384 return S.Owned(new (S.Context) ParenListExpr(S.Context, 3385 SourceLocation(), 3386 (Expr **)Args.release(), 3387 NumArgs, 3388 SourceLocation())); 3389 } 3390 3391 if (SequenceKind == NoInitialization) 3392 return S.Owned((Expr *)0); 3393 3394 QualType DestType = Entity.getType().getNonReferenceType(); 3395 // FIXME: Ugly hack around the fact that Entity.getType() is not 3396 // the same as Entity.getDecl()->getType() in cases involving type merging, 3397 // and we want latter when it makes sense. 3398 if (ResultType) 3399 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() : 3400 Entity.getType(); 3401 3402 Sema::OwningExprResult CurInit = S.Owned((Expr *)0); 3403 3404 assert(!Steps.empty() && "Cannot have an empty initialization sequence"); 3405 3406 // For initialization steps that start with a single initializer, 3407 // grab the only argument out the Args and place it into the "current" 3408 // initializer. 3409 switch (Steps.front().Kind) { 3410 case SK_ResolveAddressOfOverloadedFunction: 3411 case SK_CastDerivedToBaseRValue: 3412 case SK_CastDerivedToBaseLValue: 3413 case SK_BindReference: 3414 case SK_BindReferenceToTemporary: 3415 case SK_ExtraneousCopyToTemporary: 3416 case SK_UserConversion: 3417 case SK_QualificationConversionLValue: 3418 case SK_QualificationConversionRValue: 3419 case SK_ConversionSequence: 3420 case SK_ListInitialization: 3421 case SK_CAssignment: 3422 case SK_StringInit: 3423 assert(Args.size() == 1); 3424 CurInit = Sema::OwningExprResult(S, ((Expr **)(Args.get()))[0]->Retain()); 3425 if (CurInit.isInvalid()) 3426 return S.ExprError(); 3427 break; 3428 3429 case SK_ConstructorInitialization: 3430 case SK_ZeroInitialization: 3431 break; 3432 } 3433 3434 // Walk through the computed steps for the initialization sequence, 3435 // performing the specified conversions along the way. 3436 bool ConstructorInitRequiresZeroInit = false; 3437 for (step_iterator Step = step_begin(), StepEnd = step_end(); 3438 Step != StepEnd; ++Step) { 3439 if (CurInit.isInvalid()) 3440 return S.ExprError(); 3441 3442 Expr *CurInitExpr = (Expr *)CurInit.get(); 3443 QualType SourceType = CurInitExpr? CurInitExpr->getType() : QualType(); 3444 3445 switch (Step->Kind) { 3446 case SK_ResolveAddressOfOverloadedFunction: 3447 // Overload resolution determined which function invoke; update the 3448 // initializer to reflect that choice. 3449 S.CheckAddressOfMemberAccess(CurInitExpr, Step->Function.FoundDecl); 3450 CurInit = S.FixOverloadedFunctionReference(move(CurInit), 3451 Step->Function.FoundDecl, 3452 Step->Function.Function); 3453 break; 3454 3455 case SK_CastDerivedToBaseRValue: 3456 case SK_CastDerivedToBaseLValue: { 3457 // We have a derived-to-base cast that produces either an rvalue or an 3458 // lvalue. Perform that cast. 3459 3460 CXXBaseSpecifierArray BasePath; 3461 3462 // Casts to inaccessible base classes are allowed with C-style casts. 3463 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); 3464 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type, 3465 CurInitExpr->getLocStart(), 3466 CurInitExpr->getSourceRange(), 3467 &BasePath, IgnoreBaseAccess)) 3468 return S.ExprError(); 3469 3470 CurInit = S.Owned(new (S.Context) ImplicitCastExpr(Step->Type, 3471 CastExpr::CK_DerivedToBase, 3472 (Expr*)CurInit.release(), 3473 BasePath, 3474 Step->Kind == SK_CastDerivedToBaseLValue)); 3475 break; 3476 } 3477 3478 case SK_BindReference: 3479 if (FieldDecl *BitField = CurInitExpr->getBitField()) { 3480 // References cannot bind to bit fields (C++ [dcl.init.ref]p5). 3481 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield) 3482 << Entity.getType().isVolatileQualified() 3483 << BitField->getDeclName() 3484 << CurInitExpr->getSourceRange(); 3485 S.Diag(BitField->getLocation(), diag::note_bitfield_decl); 3486 return S.ExprError(); 3487 } 3488 3489 if (CurInitExpr->refersToVectorElement()) { 3490 // References cannot bind to vector elements. 3491 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element) 3492 << Entity.getType().isVolatileQualified() 3493 << CurInitExpr->getSourceRange(); 3494 PrintInitLocationNote(S, Entity); 3495 return S.ExprError(); 3496 } 3497 3498 // Reference binding does not have any corresponding ASTs. 3499 3500 // Check exception specifications 3501 if (S.CheckExceptionSpecCompatibility(CurInitExpr, DestType)) 3502 return S.ExprError(); 3503 3504 break; 3505 3506 case SK_BindReferenceToTemporary: 3507 // Reference binding does not have any corresponding ASTs. 3508 3509 // Check exception specifications 3510 if (S.CheckExceptionSpecCompatibility(CurInitExpr, DestType)) 3511 return S.ExprError(); 3512 3513 break; 3514 3515 case SK_ExtraneousCopyToTemporary: 3516 CurInit = CopyObject(S, Step->Type, Entity, move(CurInit), 3517 /*IsExtraneousCopy=*/true); 3518 break; 3519 3520 case SK_UserConversion: { 3521 // We have a user-defined conversion that invokes either a constructor 3522 // or a conversion function. 3523 CastExpr::CastKind CastKind = CastExpr::CK_Unknown; 3524 bool IsCopy = false; 3525 FunctionDecl *Fn = Step->Function.Function; 3526 DeclAccessPair FoundFn = Step->Function.FoundDecl; 3527 bool IsLvalue = false; 3528 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) { 3529 // Build a call to the selected constructor. 3530 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(S); 3531 SourceLocation Loc = CurInitExpr->getLocStart(); 3532 CurInit.release(); // Ownership transferred into MultiExprArg, below. 3533 3534 // Determine the arguments required to actually perform the constructor 3535 // call. 3536 if (S.CompleteConstructorCall(Constructor, 3537 Sema::MultiExprArg(S, 3538 (void **)&CurInitExpr, 3539 1), 3540 Loc, ConstructorArgs)) 3541 return S.ExprError(); 3542 3543 // Build the an expression that constructs a temporary. 3544 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor, 3545 move_arg(ConstructorArgs)); 3546 if (CurInit.isInvalid()) 3547 return S.ExprError(); 3548 3549 S.CheckConstructorAccess(Kind.getLocation(), Constructor, Entity, 3550 FoundFn.getAccess()); 3551 3552 CastKind = CastExpr::CK_ConstructorConversion; 3553 QualType Class = S.Context.getTypeDeclType(Constructor->getParent()); 3554 if (S.Context.hasSameUnqualifiedType(SourceType, Class) || 3555 S.IsDerivedFrom(SourceType, Class)) 3556 IsCopy = true; 3557 } else { 3558 // Build a call to the conversion function. 3559 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn); 3560 IsLvalue = Conversion->getResultType()->isLValueReferenceType(); 3561 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInitExpr, 0, 3562 FoundFn); 3563 3564 // FIXME: Should we move this initialization into a separate 3565 // derived-to-base conversion? I believe the answer is "no", because 3566 // we don't want to turn off access control here for c-style casts. 3567 if (S.PerformObjectArgumentInitialization(CurInitExpr, /*Qualifier=*/0, 3568 FoundFn, Conversion)) 3569 return S.ExprError(); 3570 3571 // Do a little dance to make sure that CurInit has the proper 3572 // pointer. 3573 CurInit.release(); 3574 3575 // Build the actual call to the conversion function. 3576 CurInit = S.Owned(S.BuildCXXMemberCallExpr(CurInitExpr, FoundFn, 3577 Conversion)); 3578 if (CurInit.isInvalid() || !CurInit.get()) 3579 return S.ExprError(); 3580 3581 CastKind = CastExpr::CK_UserDefinedConversion; 3582 } 3583 3584 bool RequiresCopy = !IsCopy && 3585 getKind() != InitializationSequence::ReferenceBinding; 3586 if (RequiresCopy || shouldBindAsTemporary(Entity)) 3587 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 3588 3589 CurInitExpr = CurInit.takeAs<Expr>(); 3590 CurInit = S.Owned(new (S.Context) ImplicitCastExpr(CurInitExpr->getType(), 3591 CastKind, 3592 CurInitExpr, 3593 CXXBaseSpecifierArray(), 3594 IsLvalue)); 3595 3596 if (RequiresCopy) 3597 CurInit = CopyObject(S, Entity.getType().getNonReferenceType(), Entity, 3598 move(CurInit), /*IsExtraneousCopy=*/false); 3599 break; 3600 } 3601 3602 case SK_QualificationConversionLValue: 3603 case SK_QualificationConversionRValue: 3604 // Perform a qualification conversion; these can never go wrong. 3605 S.ImpCastExprToType(CurInitExpr, Step->Type, 3606 CastExpr::CK_NoOp, 3607 Step->Kind == SK_QualificationConversionLValue); 3608 CurInit.release(); 3609 CurInit = S.Owned(CurInitExpr); 3610 break; 3611 3612 case SK_ConversionSequence: { 3613 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); 3614 3615 if (S.PerformImplicitConversion(CurInitExpr, Step->Type, *Step->ICS, 3616 Sema::AA_Converting, IgnoreBaseAccess)) 3617 return S.ExprError(); 3618 3619 CurInit.release(); 3620 CurInit = S.Owned(CurInitExpr); 3621 break; 3622 } 3623 3624 case SK_ListInitialization: { 3625 InitListExpr *InitList = cast<InitListExpr>(CurInitExpr); 3626 QualType Ty = Step->Type; 3627 if (S.CheckInitList(Entity, InitList, ResultType? *ResultType : Ty)) 3628 return S.ExprError(); 3629 3630 CurInit.release(); 3631 CurInit = S.Owned(InitList); 3632 break; 3633 } 3634 3635 case SK_ConstructorInitialization: { 3636 unsigned NumArgs = Args.size(); 3637 CXXConstructorDecl *Constructor 3638 = cast<CXXConstructorDecl>(Step->Function.Function); 3639 3640 // Build a call to the selected constructor. 3641 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(S); 3642 SourceLocation Loc = Kind.getLocation(); 3643 3644 // Determine the arguments required to actually perform the constructor 3645 // call. 3646 if (S.CompleteConstructorCall(Constructor, move(Args), 3647 Loc, ConstructorArgs)) 3648 return S.ExprError(); 3649 3650 // Build the expression that constructs a temporary. 3651 if (Entity.getKind() == InitializedEntity::EK_Temporary && 3652 NumArgs != 1 && // FIXME: Hack to work around cast weirdness 3653 (Kind.getKind() == InitializationKind::IK_Direct || 3654 Kind.getKind() == InitializationKind::IK_Value)) { 3655 // An explicitly-constructed temporary, e.g., X(1, 2). 3656 unsigned NumExprs = ConstructorArgs.size(); 3657 Expr **Exprs = (Expr **)ConstructorArgs.take(); 3658 S.MarkDeclarationReferenced(Kind.getLocation(), Constructor); 3659 CurInit = S.Owned(new (S.Context) CXXTemporaryObjectExpr(S.Context, 3660 Constructor, 3661 Entity.getType(), 3662 Kind.getLocation(), 3663 Exprs, 3664 NumExprs, 3665 Kind.getParenRange().getEnd())); 3666 } else 3667 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 3668 Constructor, 3669 move_arg(ConstructorArgs), 3670 ConstructorInitRequiresZeroInit, 3671 Entity.getKind() == InitializedEntity::EK_Base); 3672 if (CurInit.isInvalid()) 3673 return S.ExprError(); 3674 3675 // Only check access if all of that succeeded. 3676 S.CheckConstructorAccess(Loc, Constructor, Entity, 3677 Step->Function.FoundDecl.getAccess()); 3678 3679 if (shouldBindAsTemporary(Entity)) 3680 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 3681 3682 break; 3683 } 3684 3685 case SK_ZeroInitialization: { 3686 step_iterator NextStep = Step; 3687 ++NextStep; 3688 if (NextStep != StepEnd && 3689 NextStep->Kind == SK_ConstructorInitialization) { 3690 // The need for zero-initialization is recorded directly into 3691 // the call to the object's constructor within the next step. 3692 ConstructorInitRequiresZeroInit = true; 3693 } else if (Kind.getKind() == InitializationKind::IK_Value && 3694 S.getLangOptions().CPlusPlus && 3695 !Kind.isImplicitValueInit()) { 3696 CurInit = S.Owned(new (S.Context) CXXZeroInitValueExpr(Step->Type, 3697 Kind.getRange().getBegin(), 3698 Kind.getRange().getEnd())); 3699 } else { 3700 CurInit = S.Owned(new (S.Context) ImplicitValueInitExpr(Step->Type)); 3701 } 3702 break; 3703 } 3704 3705 case SK_CAssignment: { 3706 QualType SourceType = CurInitExpr->getType(); 3707 Sema::AssignConvertType ConvTy = 3708 S.CheckSingleAssignmentConstraints(Step->Type, CurInitExpr); 3709 3710 // If this is a call, allow conversion to a transparent union. 3711 if (ConvTy != Sema::Compatible && 3712 Entity.getKind() == InitializedEntity::EK_Parameter && 3713 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExpr) 3714 == Sema::Compatible) 3715 ConvTy = Sema::Compatible; 3716 3717 bool Complained; 3718 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(), 3719 Step->Type, SourceType, 3720 CurInitExpr, 3721 getAssignmentAction(Entity), 3722 &Complained)) { 3723 PrintInitLocationNote(S, Entity); 3724 return S.ExprError(); 3725 } else if (Complained) 3726 PrintInitLocationNote(S, Entity); 3727 3728 CurInit.release(); 3729 CurInit = S.Owned(CurInitExpr); 3730 break; 3731 } 3732 3733 case SK_StringInit: { 3734 QualType Ty = Step->Type; 3735 CheckStringInit(CurInitExpr, ResultType ? *ResultType : Ty, S); 3736 break; 3737 } 3738 } 3739 } 3740 3741 return move(CurInit); 3742} 3743 3744//===----------------------------------------------------------------------===// 3745// Diagnose initialization failures 3746//===----------------------------------------------------------------------===// 3747bool InitializationSequence::Diagnose(Sema &S, 3748 const InitializedEntity &Entity, 3749 const InitializationKind &Kind, 3750 Expr **Args, unsigned NumArgs) { 3751 if (SequenceKind != FailedSequence) 3752 return false; 3753 3754 QualType DestType = Entity.getType(); 3755 switch (Failure) { 3756 case FK_TooManyInitsForReference: 3757 // FIXME: Customize for the initialized entity? 3758 if (NumArgs == 0) 3759 S.Diag(Kind.getLocation(), diag::err_reference_without_init) 3760 << DestType.getNonReferenceType(); 3761 else // FIXME: diagnostic below could be better! 3762 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits) 3763 << SourceRange(Args[0]->getLocStart(), Args[NumArgs - 1]->getLocEnd()); 3764 break; 3765 3766 case FK_ArrayNeedsInitList: 3767 case FK_ArrayNeedsInitListOrStringLiteral: 3768 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) 3769 << (Failure == FK_ArrayNeedsInitListOrStringLiteral); 3770 break; 3771 3772 case FK_AddressOfOverloadFailed: { 3773 DeclAccessPair Found; 3774 S.ResolveAddressOfOverloadedFunction(Args[0], 3775 DestType.getNonReferenceType(), 3776 true, 3777 Found); 3778 break; 3779 } 3780 3781 case FK_ReferenceInitOverloadFailed: 3782 case FK_UserConversionOverloadFailed: 3783 switch (FailedOverloadResult) { 3784 case OR_Ambiguous: 3785 if (Failure == FK_UserConversionOverloadFailed) 3786 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition) 3787 << Args[0]->getType() << DestType 3788 << Args[0]->getSourceRange(); 3789 else 3790 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous) 3791 << DestType << Args[0]->getType() 3792 << Args[0]->getSourceRange(); 3793 3794 S.PrintOverloadCandidates(FailedCandidateSet, Sema::OCD_ViableCandidates, 3795 Args, NumArgs); 3796 break; 3797 3798 case OR_No_Viable_Function: 3799 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition) 3800 << Args[0]->getType() << DestType.getNonReferenceType() 3801 << Args[0]->getSourceRange(); 3802 S.PrintOverloadCandidates(FailedCandidateSet, Sema::OCD_AllCandidates, 3803 Args, NumArgs); 3804 break; 3805 3806 case OR_Deleted: { 3807 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function) 3808 << Args[0]->getType() << DestType.getNonReferenceType() 3809 << Args[0]->getSourceRange(); 3810 OverloadCandidateSet::iterator Best; 3811 OverloadingResult Ovl = S.BestViableFunction(FailedCandidateSet, 3812 Kind.getLocation(), 3813 Best); 3814 if (Ovl == OR_Deleted) { 3815 S.Diag(Best->Function->getLocation(), diag::note_unavailable_here) 3816 << Best->Function->isDeleted(); 3817 } else { 3818 llvm_unreachable("Inconsistent overload resolution?"); 3819 } 3820 break; 3821 } 3822 3823 case OR_Success: 3824 llvm_unreachable("Conversion did not fail!"); 3825 break; 3826 } 3827 break; 3828 3829 case FK_NonConstLValueReferenceBindingToTemporary: 3830 case FK_NonConstLValueReferenceBindingToUnrelated: 3831 S.Diag(Kind.getLocation(), 3832 Failure == FK_NonConstLValueReferenceBindingToTemporary 3833 ? diag::err_lvalue_reference_bind_to_temporary 3834 : diag::err_lvalue_reference_bind_to_unrelated) 3835 << DestType.getNonReferenceType().isVolatileQualified() 3836 << DestType.getNonReferenceType() 3837 << Args[0]->getType() 3838 << Args[0]->getSourceRange(); 3839 break; 3840 3841 case FK_RValueReferenceBindingToLValue: 3842 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref) 3843 << Args[0]->getSourceRange(); 3844 break; 3845 3846 case FK_ReferenceInitDropsQualifiers: 3847 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals) 3848 << DestType.getNonReferenceType() 3849 << Args[0]->getType() 3850 << Args[0]->getSourceRange(); 3851 break; 3852 3853 case FK_ReferenceInitFailed: 3854 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed) 3855 << DestType.getNonReferenceType() 3856 << (Args[0]->isLvalue(S.Context) == Expr::LV_Valid) 3857 << Args[0]->getType() 3858 << Args[0]->getSourceRange(); 3859 break; 3860 3861 case FK_ConversionFailed: 3862 S.Diag(Kind.getLocation(), diag::err_init_conversion_failed) 3863 << (int)Entity.getKind() 3864 << DestType 3865 << (Args[0]->isLvalue(S.Context) == Expr::LV_Valid) 3866 << Args[0]->getType() 3867 << Args[0]->getSourceRange(); 3868 break; 3869 3870 case FK_TooManyInitsForScalar: { 3871 SourceRange R; 3872 3873 if (InitListExpr *InitList = dyn_cast<InitListExpr>(Args[0])) 3874 R = SourceRange(InitList->getInit(1)->getLocStart(), 3875 InitList->getLocEnd()); 3876 else 3877 R = SourceRange(Args[0]->getLocStart(), Args[NumArgs - 1]->getLocEnd()); 3878 3879 S.Diag(Kind.getLocation(), diag::err_excess_initializers) 3880 << /*scalar=*/2 << R; 3881 break; 3882 } 3883 3884 case FK_ReferenceBindingToInitList: 3885 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list) 3886 << DestType.getNonReferenceType() << Args[0]->getSourceRange(); 3887 break; 3888 3889 case FK_InitListBadDestinationType: 3890 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type) 3891 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange(); 3892 break; 3893 3894 case FK_ConstructorOverloadFailed: { 3895 SourceRange ArgsRange; 3896 if (NumArgs) 3897 ArgsRange = SourceRange(Args[0]->getLocStart(), 3898 Args[NumArgs - 1]->getLocEnd()); 3899 3900 // FIXME: Using "DestType" for the entity we're printing is probably 3901 // bad. 3902 switch (FailedOverloadResult) { 3903 case OR_Ambiguous: 3904 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init) 3905 << DestType << ArgsRange; 3906 S.PrintOverloadCandidates(FailedCandidateSet, 3907 Sema::OCD_ViableCandidates, Args, NumArgs); 3908 break; 3909 3910 case OR_No_Viable_Function: 3911 if (Kind.getKind() == InitializationKind::IK_Default && 3912 (Entity.getKind() == InitializedEntity::EK_Base || 3913 Entity.getKind() == InitializedEntity::EK_Member) && 3914 isa<CXXConstructorDecl>(S.CurContext)) { 3915 // This is implicit default initialization of a member or 3916 // base within a constructor. If no viable function was 3917 // found, notify the user that she needs to explicitly 3918 // initialize this base/member. 3919 CXXConstructorDecl *Constructor 3920 = cast<CXXConstructorDecl>(S.CurContext); 3921 if (Entity.getKind() == InitializedEntity::EK_Base) { 3922 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 3923 << Constructor->isImplicit() 3924 << S.Context.getTypeDeclType(Constructor->getParent()) 3925 << /*base=*/0 3926 << Entity.getType(); 3927 3928 RecordDecl *BaseDecl 3929 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>() 3930 ->getDecl(); 3931 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl) 3932 << S.Context.getTagDeclType(BaseDecl); 3933 } else { 3934 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 3935 << Constructor->isImplicit() 3936 << S.Context.getTypeDeclType(Constructor->getParent()) 3937 << /*member=*/1 3938 << Entity.getName(); 3939 S.Diag(Entity.getDecl()->getLocation(), diag::note_field_decl); 3940 3941 if (const RecordType *Record 3942 = Entity.getType()->getAs<RecordType>()) 3943 S.Diag(Record->getDecl()->getLocation(), 3944 diag::note_previous_decl) 3945 << S.Context.getTagDeclType(Record->getDecl()); 3946 } 3947 break; 3948 } 3949 3950 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init) 3951 << DestType << ArgsRange; 3952 S.PrintOverloadCandidates(FailedCandidateSet, Sema::OCD_AllCandidates, 3953 Args, NumArgs); 3954 break; 3955 3956 case OR_Deleted: { 3957 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) 3958 << true << DestType << ArgsRange; 3959 OverloadCandidateSet::iterator Best; 3960 OverloadingResult Ovl = S.BestViableFunction(FailedCandidateSet, 3961 Kind.getLocation(), 3962 Best); 3963 if (Ovl == OR_Deleted) { 3964 S.Diag(Best->Function->getLocation(), diag::note_unavailable_here) 3965 << Best->Function->isDeleted(); 3966 } else { 3967 llvm_unreachable("Inconsistent overload resolution?"); 3968 } 3969 break; 3970 } 3971 3972 case OR_Success: 3973 llvm_unreachable("Conversion did not fail!"); 3974 break; 3975 } 3976 break; 3977 } 3978 3979 case FK_DefaultInitOfConst: 3980 if (Entity.getKind() == InitializedEntity::EK_Member && 3981 isa<CXXConstructorDecl>(S.CurContext)) { 3982 // This is implicit default-initialization of a const member in 3983 // a constructor. Complain that it needs to be explicitly 3984 // initialized. 3985 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext); 3986 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor) 3987 << Constructor->isImplicit() 3988 << S.Context.getTypeDeclType(Constructor->getParent()) 3989 << /*const=*/1 3990 << Entity.getName(); 3991 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl) 3992 << Entity.getName(); 3993 } else { 3994 S.Diag(Kind.getLocation(), diag::err_default_init_const) 3995 << DestType << (bool)DestType->getAs<RecordType>(); 3996 } 3997 break; 3998 } 3999 4000 PrintInitLocationNote(S, Entity); 4001 return true; 4002} 4003 4004void InitializationSequence::dump(llvm::raw_ostream &OS) const { 4005 switch (SequenceKind) { 4006 case FailedSequence: { 4007 OS << "Failed sequence: "; 4008 switch (Failure) { 4009 case FK_TooManyInitsForReference: 4010 OS << "too many initializers for reference"; 4011 break; 4012 4013 case FK_ArrayNeedsInitList: 4014 OS << "array requires initializer list"; 4015 break; 4016 4017 case FK_ArrayNeedsInitListOrStringLiteral: 4018 OS << "array requires initializer list or string literal"; 4019 break; 4020 4021 case FK_AddressOfOverloadFailed: 4022 OS << "address of overloaded function failed"; 4023 break; 4024 4025 case FK_ReferenceInitOverloadFailed: 4026 OS << "overload resolution for reference initialization failed"; 4027 break; 4028 4029 case FK_NonConstLValueReferenceBindingToTemporary: 4030 OS << "non-const lvalue reference bound to temporary"; 4031 break; 4032 4033 case FK_NonConstLValueReferenceBindingToUnrelated: 4034 OS << "non-const lvalue reference bound to unrelated type"; 4035 break; 4036 4037 case FK_RValueReferenceBindingToLValue: 4038 OS << "rvalue reference bound to an lvalue"; 4039 break; 4040 4041 case FK_ReferenceInitDropsQualifiers: 4042 OS << "reference initialization drops qualifiers"; 4043 break; 4044 4045 case FK_ReferenceInitFailed: 4046 OS << "reference initialization failed"; 4047 break; 4048 4049 case FK_ConversionFailed: 4050 OS << "conversion failed"; 4051 break; 4052 4053 case FK_TooManyInitsForScalar: 4054 OS << "too many initializers for scalar"; 4055 break; 4056 4057 case FK_ReferenceBindingToInitList: 4058 OS << "referencing binding to initializer list"; 4059 break; 4060 4061 case FK_InitListBadDestinationType: 4062 OS << "initializer list for non-aggregate, non-scalar type"; 4063 break; 4064 4065 case FK_UserConversionOverloadFailed: 4066 OS << "overloading failed for user-defined conversion"; 4067 break; 4068 4069 case FK_ConstructorOverloadFailed: 4070 OS << "constructor overloading failed"; 4071 break; 4072 4073 case FK_DefaultInitOfConst: 4074 OS << "default initialization of a const variable"; 4075 break; 4076 } 4077 OS << '\n'; 4078 return; 4079 } 4080 4081 case DependentSequence: 4082 OS << "Dependent sequence: "; 4083 return; 4084 4085 case UserDefinedConversion: 4086 OS << "User-defined conversion sequence: "; 4087 break; 4088 4089 case ConstructorInitialization: 4090 OS << "Constructor initialization sequence: "; 4091 break; 4092 4093 case ReferenceBinding: 4094 OS << "Reference binding: "; 4095 break; 4096 4097 case ListInitialization: 4098 OS << "List initialization: "; 4099 break; 4100 4101 case ZeroInitialization: 4102 OS << "Zero initialization\n"; 4103 return; 4104 4105 case NoInitialization: 4106 OS << "No initialization\n"; 4107 return; 4108 4109 case StandardConversion: 4110 OS << "Standard conversion: "; 4111 break; 4112 4113 case CAssignment: 4114 OS << "C assignment: "; 4115 break; 4116 4117 case StringInit: 4118 OS << "String initialization: "; 4119 break; 4120 } 4121 4122 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) { 4123 if (S != step_begin()) { 4124 OS << " -> "; 4125 } 4126 4127 switch (S->Kind) { 4128 case SK_ResolveAddressOfOverloadedFunction: 4129 OS << "resolve address of overloaded function"; 4130 break; 4131 4132 case SK_CastDerivedToBaseRValue: 4133 OS << "derived-to-base case (rvalue" << S->Type.getAsString() << ")"; 4134 break; 4135 4136 case SK_CastDerivedToBaseLValue: 4137 OS << "derived-to-base case (lvalue" << S->Type.getAsString() << ")"; 4138 break; 4139 4140 case SK_BindReference: 4141 OS << "bind reference to lvalue"; 4142 break; 4143 4144 case SK_BindReferenceToTemporary: 4145 OS << "bind reference to a temporary"; 4146 break; 4147 4148 case SK_ExtraneousCopyToTemporary: 4149 OS << "extraneous C++03 copy to temporary"; 4150 break; 4151 4152 case SK_UserConversion: 4153 OS << "user-defined conversion via " << S->Function.Function; 4154 break; 4155 4156 case SK_QualificationConversionRValue: 4157 OS << "qualification conversion (rvalue)"; 4158 4159 case SK_QualificationConversionLValue: 4160 OS << "qualification conversion (lvalue)"; 4161 break; 4162 4163 case SK_ConversionSequence: 4164 OS << "implicit conversion sequence ("; 4165 S->ICS->DebugPrint(); // FIXME: use OS 4166 OS << ")"; 4167 break; 4168 4169 case SK_ListInitialization: 4170 OS << "list initialization"; 4171 break; 4172 4173 case SK_ConstructorInitialization: 4174 OS << "constructor initialization"; 4175 break; 4176 4177 case SK_ZeroInitialization: 4178 OS << "zero initialization"; 4179 break; 4180 4181 case SK_CAssignment: 4182 OS << "C assignment"; 4183 break; 4184 4185 case SK_StringInit: 4186 OS << "string initialization"; 4187 break; 4188 } 4189 } 4190} 4191 4192void InitializationSequence::dump() const { 4193 dump(llvm::errs()); 4194} 4195 4196//===----------------------------------------------------------------------===// 4197// Initialization helper functions 4198//===----------------------------------------------------------------------===// 4199Sema::OwningExprResult 4200Sema::PerformCopyInitialization(const InitializedEntity &Entity, 4201 SourceLocation EqualLoc, 4202 OwningExprResult Init) { 4203 if (Init.isInvalid()) 4204 return ExprError(); 4205 4206 Expr *InitE = (Expr *)Init.get(); 4207 assert(InitE && "No initialization expression?"); 4208 4209 if (EqualLoc.isInvalid()) 4210 EqualLoc = InitE->getLocStart(); 4211 4212 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(), 4213 EqualLoc); 4214 InitializationSequence Seq(*this, Entity, Kind, &InitE, 1); 4215 Init.release(); 4216 return Seq.Perform(*this, Entity, Kind, 4217 MultiExprArg(*this, (void**)&InitE, 1)); 4218} 4219