1 //===--- SemaInit.cpp - Semantic Analysis for Initializers ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements semantic analysis for initializers.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Sema/Initialization.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/DeclObjC.h"
17 #include "clang/AST/ExprCXX.h"
18 #include "clang/AST/ExprObjC.h"
19 #include "clang/AST/TypeLoc.h"
20 #include "clang/Basic/TargetInfo.h"
21 #include "clang/Sema/Designator.h"
22 #include "clang/Sema/Lookup.h"
23 #include "clang/Sema/SemaInternal.h"
24 #include "llvm/ADT/APInt.h"
25 #include "llvm/ADT/SmallString.h"
26 #include "llvm/Support/ErrorHandling.h"
27 #include "llvm/Support/raw_ostream.h"
29 using namespace clang;
31 //===----------------------------------------------------------------------===//
32 // Sema Initialization Checking
33 //===----------------------------------------------------------------------===//
35 /// \brief Check whether T is compatible with a wide character type (wchar_t,
36 /// char16_t or char32_t).
37 static bool IsWideCharCompatible(QualType T, ASTContext &Context) {
38 if (Context.typesAreCompatible(Context.getWideCharType(), T))
40 if (Context.getLangOpts().CPlusPlus || Context.getLangOpts().C11) {
41 return Context.typesAreCompatible(Context.Char16Ty, T) ||
42 Context.typesAreCompatible(Context.Char32Ty, T);
47 enum StringInitFailureKind {
49 SIF_NarrowStringIntoWideChar,
50 SIF_WideStringIntoChar,
51 SIF_IncompatWideStringIntoWideChar,
55 /// \brief Check whether the array of type AT can be initialized by the Init
56 /// expression by means of string initialization. Returns SIF_None if so,
57 /// otherwise returns a StringInitFailureKind that describes why the
58 /// initialization would not work.
59 static StringInitFailureKind IsStringInit(Expr *Init, const ArrayType *AT,
60 ASTContext &Context) {
61 if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT))
64 // See if this is a string literal or @encode.
65 Init = Init->IgnoreParens();
67 // Handle @encode, which is a narrow string.
68 if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType())
71 // Otherwise we can only handle string literals.
72 StringLiteral *SL = dyn_cast<StringLiteral>(Init);
76 const QualType ElemTy =
77 Context.getCanonicalType(AT->getElementType()).getUnqualifiedType();
79 switch (SL->getKind()) {
80 case StringLiteral::Ascii:
81 case StringLiteral::UTF8:
82 // char array can be initialized with a narrow string.
83 // Only allow char x[] = "foo"; not char x[] = L"foo";
84 if (ElemTy->isCharType())
86 if (IsWideCharCompatible(ElemTy, Context))
87 return SIF_NarrowStringIntoWideChar;
89 // C99 6.7.8p15 (with correction from DR343), or C11 6.7.9p15:
90 // "An array with element type compatible with a qualified or unqualified
91 // version of wchar_t, char16_t, or char32_t may be initialized by a wide
92 // string literal with the corresponding encoding prefix (L, u, or U,
93 // respectively), optionally enclosed in braces.
94 case StringLiteral::UTF16:
95 if (Context.typesAreCompatible(Context.Char16Ty, ElemTy))
97 if (ElemTy->isCharType())
98 return SIF_WideStringIntoChar;
99 if (IsWideCharCompatible(ElemTy, Context))
100 return SIF_IncompatWideStringIntoWideChar;
102 case StringLiteral::UTF32:
103 if (Context.typesAreCompatible(Context.Char32Ty, ElemTy))
105 if (ElemTy->isCharType())
106 return SIF_WideStringIntoChar;
107 if (IsWideCharCompatible(ElemTy, Context))
108 return SIF_IncompatWideStringIntoWideChar;
110 case StringLiteral::Wide:
111 if (Context.typesAreCompatible(Context.getWideCharType(), ElemTy))
113 if (ElemTy->isCharType())
114 return SIF_WideStringIntoChar;
115 if (IsWideCharCompatible(ElemTy, Context))
116 return SIF_IncompatWideStringIntoWideChar;
120 llvm_unreachable("missed a StringLiteral kind?");
123 static StringInitFailureKind IsStringInit(Expr *init, QualType declType,
124 ASTContext &Context) {
125 const ArrayType *arrayType = Context.getAsArrayType(declType);
128 return IsStringInit(init, arrayType, Context);
131 /// Update the type of a string literal, including any surrounding parentheses,
132 /// to match the type of the object which it is initializing.
133 static void updateStringLiteralType(Expr *E, QualType Ty) {
136 if (isa<StringLiteral>(E) || isa<ObjCEncodeExpr>(E))
138 else if (ParenExpr *PE = dyn_cast<ParenExpr>(E))
139 E = PE->getSubExpr();
140 else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
141 E = UO->getSubExpr();
142 else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E))
143 E = GSE->getResultExpr();
145 llvm_unreachable("unexpected expr in string literal init");
149 static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT,
151 // Get the length of the string as parsed.
152 auto *ConstantArrayTy =
153 cast<ConstantArrayType>(Str->getType()->getAsArrayTypeUnsafe());
154 uint64_t StrLength = ConstantArrayTy->getSize().getZExtValue();
156 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
157 // C99 6.7.8p14. We have an array of character type with unknown size
158 // being initialized to a string literal.
159 llvm::APInt ConstVal(32, StrLength);
160 // Return a new array type (C99 6.7.8p22).
161 DeclT = S.Context.getConstantArrayType(IAT->getElementType(),
163 ArrayType::Normal, 0);
164 updateStringLiteralType(Str, DeclT);
168 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT);
170 // We have an array of character type with known size. However,
171 // the size may be smaller or larger than the string we are initializing.
172 // FIXME: Avoid truncation for 64-bit length strings.
173 if (S.getLangOpts().CPlusPlus) {
174 if (StringLiteral *SL = dyn_cast<StringLiteral>(Str->IgnoreParens())) {
175 // For Pascal strings it's OK to strip off the terminating null character,
176 // so the example below is valid:
178 // unsigned char a[2] = "\pa";
183 // [dcl.init.string]p2
184 if (StrLength > CAT->getSize().getZExtValue())
185 S.Diag(Str->getLocStart(),
186 diag::err_initializer_string_for_char_array_too_long)
187 << Str->getSourceRange();
190 if (StrLength-1 > CAT->getSize().getZExtValue())
191 S.Diag(Str->getLocStart(),
192 diag::ext_initializer_string_for_char_array_too_long)
193 << Str->getSourceRange();
196 // Set the type to the actual size that we are initializing. If we have
198 // char x[1] = "foo";
199 // then this will set the string literal's type to char[1].
200 updateStringLiteralType(Str, DeclT);
203 //===----------------------------------------------------------------------===//
204 // Semantic checking for initializer lists.
205 //===----------------------------------------------------------------------===//
207 /// @brief Semantic checking for initializer lists.
209 /// The InitListChecker class contains a set of routines that each
210 /// handle the initialization of a certain kind of entity, e.g.,
211 /// arrays, vectors, struct/union types, scalars, etc. The
212 /// InitListChecker itself performs a recursive walk of the subobject
213 /// structure of the type to be initialized, while stepping through
214 /// the initializer list one element at a time. The IList and Index
215 /// parameters to each of the Check* routines contain the active
216 /// (syntactic) initializer list and the index into that initializer
217 /// list that represents the current initializer. Each routine is
218 /// responsible for moving that Index forward as it consumes elements.
220 /// Each Check* routine also has a StructuredList/StructuredIndex
221 /// arguments, which contains the current "structured" (semantic)
222 /// initializer list and the index into that initializer list where we
223 /// are copying initializers as we map them over to the semantic
224 /// list. Once we have completed our recursive walk of the subobject
225 /// structure, we will have constructed a full semantic initializer
228 /// C99 designators cause changes in the initializer list traversal,
229 /// because they make the initialization "jump" into a specific
230 /// subobject and then continue the initialization from that
231 /// point. CheckDesignatedInitializer() recursively steps into the
232 /// designated subobject and manages backing out the recursion to
233 /// initialize the subobjects after the one designated.
235 class InitListChecker {
238 bool VerifyOnly; // no diagnostics, no structure building
239 llvm::DenseMap<InitListExpr *, InitListExpr *> SyntacticToSemantic;
240 InitListExpr *FullyStructuredList;
242 void CheckImplicitInitList(const InitializedEntity &Entity,
243 InitListExpr *ParentIList, QualType T,
244 unsigned &Index, InitListExpr *StructuredList,
245 unsigned &StructuredIndex);
246 void CheckExplicitInitList(const InitializedEntity &Entity,
247 InitListExpr *IList, QualType &T,
248 InitListExpr *StructuredList,
249 bool TopLevelObject = false);
250 void CheckListElementTypes(const InitializedEntity &Entity,
251 InitListExpr *IList, QualType &DeclType,
252 bool SubobjectIsDesignatorContext,
254 InitListExpr *StructuredList,
255 unsigned &StructuredIndex,
256 bool TopLevelObject = false);
257 void CheckSubElementType(const InitializedEntity &Entity,
258 InitListExpr *IList, QualType ElemType,
260 InitListExpr *StructuredList,
261 unsigned &StructuredIndex);
262 void CheckComplexType(const InitializedEntity &Entity,
263 InitListExpr *IList, QualType DeclType,
265 InitListExpr *StructuredList,
266 unsigned &StructuredIndex);
267 void CheckScalarType(const InitializedEntity &Entity,
268 InitListExpr *IList, QualType DeclType,
270 InitListExpr *StructuredList,
271 unsigned &StructuredIndex);
272 void CheckReferenceType(const InitializedEntity &Entity,
273 InitListExpr *IList, QualType DeclType,
275 InitListExpr *StructuredList,
276 unsigned &StructuredIndex);
277 void CheckVectorType(const InitializedEntity &Entity,
278 InitListExpr *IList, QualType DeclType, unsigned &Index,
279 InitListExpr *StructuredList,
280 unsigned &StructuredIndex);
281 void CheckStructUnionTypes(const InitializedEntity &Entity,
282 InitListExpr *IList, QualType DeclType,
283 RecordDecl::field_iterator Field,
284 bool SubobjectIsDesignatorContext, unsigned &Index,
285 InitListExpr *StructuredList,
286 unsigned &StructuredIndex,
287 bool TopLevelObject = false);
288 void CheckArrayType(const InitializedEntity &Entity,
289 InitListExpr *IList, QualType &DeclType,
290 llvm::APSInt elementIndex,
291 bool SubobjectIsDesignatorContext, unsigned &Index,
292 InitListExpr *StructuredList,
293 unsigned &StructuredIndex);
294 bool CheckDesignatedInitializer(const InitializedEntity &Entity,
295 InitListExpr *IList, DesignatedInitExpr *DIE,
297 QualType &CurrentObjectType,
298 RecordDecl::field_iterator *NextField,
299 llvm::APSInt *NextElementIndex,
301 InitListExpr *StructuredList,
302 unsigned &StructuredIndex,
303 bool FinishSubobjectInit,
304 bool TopLevelObject);
305 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
306 QualType CurrentObjectType,
307 InitListExpr *StructuredList,
308 unsigned StructuredIndex,
309 SourceRange InitRange);
310 void UpdateStructuredListElement(InitListExpr *StructuredList,
311 unsigned &StructuredIndex,
313 int numArrayElements(QualType DeclType);
314 int numStructUnionElements(QualType DeclType);
316 static ExprResult PerformEmptyInit(Sema &SemaRef,
318 const InitializedEntity &Entity,
320 void FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
321 const InitializedEntity &ParentEntity,
322 InitListExpr *ILE, bool &RequiresSecondPass);
323 void FillInEmptyInitializations(const InitializedEntity &Entity,
324 InitListExpr *ILE, bool &RequiresSecondPass);
325 bool CheckFlexibleArrayInit(const InitializedEntity &Entity,
326 Expr *InitExpr, FieldDecl *Field,
327 bool TopLevelObject);
328 void CheckEmptyInitializable(const InitializedEntity &Entity,
332 InitListChecker(Sema &S, const InitializedEntity &Entity,
333 InitListExpr *IL, QualType &T, bool VerifyOnly);
334 bool HadError() { return hadError; }
336 // @brief Retrieves the fully-structured initializer list used for
337 // semantic analysis and code generation.
338 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; }
340 } // end anonymous namespace
342 ExprResult InitListChecker::PerformEmptyInit(Sema &SemaRef,
344 const InitializedEntity &Entity,
346 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc,
348 MultiExprArg SubInit;
350 InitListExpr DummyInitList(SemaRef.Context, Loc, None, Loc);
352 // C++ [dcl.init.aggr]p7:
353 // If there are fewer initializer-clauses in the list than there are
354 // members in the aggregate, then each member not explicitly initialized
356 bool EmptyInitList = SemaRef.getLangOpts().CPlusPlus11 &&
357 Entity.getType()->getBaseElementTypeUnsafe()->isRecordType();
360 // shall be initialized [...] from an empty initializer list.
362 // We apply the resolution of this DR to C++11 but not C++98, since C++98
363 // does not have useful semantics for initialization from an init list.
364 // We treat this as copy-initialization, because aggregate initialization
365 // always performs copy-initialization on its elements.
367 // Only do this if we're initializing a class type, to avoid filling in
368 // the initializer list where possible.
369 InitExpr = VerifyOnly ? &DummyInitList : new (SemaRef.Context)
370 InitListExpr(SemaRef.Context, Loc, None, Loc);
371 InitExpr->setType(SemaRef.Context.VoidTy);
373 Kind = InitializationKind::CreateCopy(Loc, Loc);
376 // shall be value-initialized.
379 InitializationSequence InitSeq(SemaRef, Entity, Kind, SubInit);
380 // libstdc++4.6 marks the vector default constructor as explicit in
381 // _GLIBCXX_DEBUG mode, so recover using the C++03 logic in that case.
382 // stlport does so too. Look for std::__debug for libstdc++, and for
383 // std:: for stlport. This is effectively a compiler-side implementation of
385 if (!InitSeq && EmptyInitList && InitSeq.getFailureKind() ==
386 InitializationSequence::FK_ExplicitConstructor) {
387 OverloadCandidateSet::iterator Best;
388 OverloadingResult O =
389 InitSeq.getFailedCandidateSet()
390 .BestViableFunction(SemaRef, Kind.getLocation(), Best);
392 assert(O == OR_Success && "Inconsistent overload resolution");
393 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
394 CXXRecordDecl *R = CtorDecl->getParent();
396 if (CtorDecl->getMinRequiredArguments() == 0 &&
397 CtorDecl->isExplicit() && R->getDeclName() &&
398 SemaRef.SourceMgr.isInSystemHeader(CtorDecl->getLocation())) {
401 bool IsInStd = false;
402 for (NamespaceDecl *ND = dyn_cast<NamespaceDecl>(R->getDeclContext());
403 ND && !IsInStd; ND = dyn_cast<NamespaceDecl>(ND->getParent())) {
404 if (SemaRef.getStdNamespace()->InEnclosingNamespaceSetOf(ND))
408 if (IsInStd && llvm::StringSwitch<bool>(R->getName())
409 .Cases("basic_string", "deque", "forward_list", true)
410 .Cases("list", "map", "multimap", "multiset", true)
411 .Cases("priority_queue", "queue", "set", "stack", true)
412 .Cases("unordered_map", "unordered_set", "vector", true)
414 InitSeq.InitializeFrom(
416 InitializationKind::CreateValue(Loc, Loc, Loc, true),
417 MultiExprArg(), /*TopLevelOfInitList=*/false);
418 // Emit a warning for this. System header warnings aren't shown
419 // by default, but people working on system headers should see it.
421 SemaRef.Diag(CtorDecl->getLocation(),
422 diag::warn_invalid_initializer_from_system_header);
423 SemaRef.Diag(Entity.getDecl()->getLocation(),
424 diag::note_used_in_initialization_here);
431 InitSeq.Diagnose(SemaRef, Entity, Kind, SubInit);
432 if (Entity.getKind() == InitializedEntity::EK_Member)
433 SemaRef.Diag(Entity.getDecl()->getLocation(),
434 diag::note_in_omitted_aggregate_initializer)
435 << /*field*/1 << Entity.getDecl();
436 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement)
437 SemaRef.Diag(Loc, diag::note_in_omitted_aggregate_initializer)
438 << /*array element*/0 << Entity.getElementIndex();
443 return VerifyOnly ? ExprResult(static_cast<Expr *>(nullptr))
444 : InitSeq.Perform(SemaRef, Entity, Kind, SubInit);
447 void InitListChecker::CheckEmptyInitializable(const InitializedEntity &Entity,
448 SourceLocation Loc) {
450 "CheckEmptyInitializable is only inteded for verification mode.");
451 if (PerformEmptyInit(SemaRef, Loc, Entity, /*VerifyOnly*/true).isInvalid())
455 void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
456 const InitializedEntity &ParentEntity,
458 bool &RequiresSecondPass) {
459 SourceLocation Loc = ILE->getLocEnd();
460 unsigned NumInits = ILE->getNumInits();
461 InitializedEntity MemberEntity
462 = InitializedEntity::InitializeMember(Field, &ParentEntity);
463 if (Init >= NumInits || !ILE->getInit(Init)) {
464 // C++1y [dcl.init.aggr]p7:
465 // If there are fewer initializer-clauses in the list than there are
466 // members in the aggregate, then each member not explicitly initialized
467 // shall be initialized from its brace-or-equal-initializer [...]
468 if (Field->hasInClassInitializer()) {
469 ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
470 if (DIE.isInvalid()) {
475 ILE->setInit(Init, DIE.get());
477 ILE->updateInit(SemaRef.Context, Init, DIE.get());
478 RequiresSecondPass = true;
483 if (Field->getType()->isReferenceType()) {
484 // C++ [dcl.init.aggr]p9:
485 // If an incomplete or empty initializer-list leaves a
486 // member of reference type uninitialized, the program is
488 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized)
490 << ILE->getSyntacticForm()->getSourceRange();
491 SemaRef.Diag(Field->getLocation(),
492 diag::note_uninit_reference_member);
497 ExprResult MemberInit = PerformEmptyInit(SemaRef, Loc, MemberEntity,
498 /*VerifyOnly*/false);
499 if (MemberInit.isInvalid()) {
506 } else if (Init < NumInits) {
507 ILE->setInit(Init, MemberInit.getAs<Expr>());
508 } else if (!isa<ImplicitValueInitExpr>(MemberInit.get())) {
509 // Empty initialization requires a constructor call, so
510 // extend the initializer list to include the constructor
511 // call and make a note that we'll need to take another pass
512 // through the initializer list.
513 ILE->updateInit(SemaRef.Context, Init, MemberInit.getAs<Expr>());
514 RequiresSecondPass = true;
516 } else if (InitListExpr *InnerILE
517 = dyn_cast<InitListExpr>(ILE->getInit(Init)))
518 FillInEmptyInitializations(MemberEntity, InnerILE,
522 /// Recursively replaces NULL values within the given initializer list
523 /// with expressions that perform value-initialization of the
524 /// appropriate type.
526 InitListChecker::FillInEmptyInitializations(const InitializedEntity &Entity,
528 bool &RequiresSecondPass) {
529 assert((ILE->getType() != SemaRef.Context.VoidTy) &&
530 "Should not have void type");
532 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
533 const RecordDecl *RDecl = RType->getDecl();
534 if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
535 FillInEmptyInitForField(0, ILE->getInitializedFieldInUnion(),
536 Entity, ILE, RequiresSecondPass);
537 else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
538 cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
539 for (auto *Field : RDecl->fields()) {
540 if (Field->hasInClassInitializer()) {
541 FillInEmptyInitForField(0, Field, Entity, ILE, RequiresSecondPass);
547 for (auto *Field : RDecl->fields()) {
548 if (Field->isUnnamedBitfield())
554 FillInEmptyInitForField(Init, Field, Entity, ILE, RequiresSecondPass);
560 // Only look at the first initialization of a union.
561 if (RDecl->isUnion())
569 QualType ElementType;
571 InitializedEntity ElementEntity = Entity;
572 unsigned NumInits = ILE->getNumInits();
573 unsigned NumElements = NumInits;
574 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) {
575 ElementType = AType->getElementType();
576 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType))
577 NumElements = CAType->getSize().getZExtValue();
578 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
580 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) {
581 ElementType = VType->getElementType();
582 NumElements = VType->getNumElements();
583 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
586 ElementType = ILE->getType();
588 for (unsigned Init = 0; Init != NumElements; ++Init) {
592 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement ||
593 ElementEntity.getKind() == InitializedEntity::EK_VectorElement)
594 ElementEntity.setElementIndex(Init);
596 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : nullptr);
597 if (!InitExpr && !ILE->hasArrayFiller()) {
598 ExprResult ElementInit = PerformEmptyInit(SemaRef, ILE->getLocEnd(),
600 /*VerifyOnly*/false);
601 if (ElementInit.isInvalid()) {
608 } else if (Init < NumInits) {
609 // For arrays, just set the expression used for value-initialization
610 // of the "holes" in the array.
611 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement)
612 ILE->setArrayFiller(ElementInit.getAs<Expr>());
614 ILE->setInit(Init, ElementInit.getAs<Expr>());
616 // For arrays, just set the expression used for value-initialization
617 // of the rest of elements and exit.
618 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) {
619 ILE->setArrayFiller(ElementInit.getAs<Expr>());
623 if (!isa<ImplicitValueInitExpr>(ElementInit.get())) {
624 // Empty initialization requires a constructor call, so
625 // extend the initializer list to include the constructor
626 // call and make a note that we'll need to take another pass
627 // through the initializer list.
628 ILE->updateInit(SemaRef.Context, Init, ElementInit.getAs<Expr>());
629 RequiresSecondPass = true;
632 } else if (InitListExpr *InnerILE
633 = dyn_cast_or_null<InitListExpr>(InitExpr))
634 FillInEmptyInitializations(ElementEntity, InnerILE, RequiresSecondPass);
639 InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity,
640 InitListExpr *IL, QualType &T,
642 : SemaRef(S), VerifyOnly(VerifyOnly) {
643 // FIXME: Check that IL isn't already the semantic form of some other
644 // InitListExpr. If it is, we'd create a broken AST.
648 FullyStructuredList =
649 getStructuredSubobjectInit(IL, 0, T, nullptr, 0, IL->getSourceRange());
650 CheckExplicitInitList(Entity, IL, T, FullyStructuredList,
651 /*TopLevelObject=*/true);
653 if (!hadError && !VerifyOnly) {
654 bool RequiresSecondPass = false;
655 FillInEmptyInitializations(Entity, FullyStructuredList, RequiresSecondPass);
656 if (RequiresSecondPass && !hadError)
657 FillInEmptyInitializations(Entity, FullyStructuredList,
662 int InitListChecker::numArrayElements(QualType DeclType) {
663 // FIXME: use a proper constant
664 int maxElements = 0x7FFFFFFF;
665 if (const ConstantArrayType *CAT =
666 SemaRef.Context.getAsConstantArrayType(DeclType)) {
667 maxElements = static_cast<int>(CAT->getSize().getZExtValue());
672 int InitListChecker::numStructUnionElements(QualType DeclType) {
673 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
674 int InitializableMembers = 0;
675 for (const auto *Field : structDecl->fields())
676 if (!Field->isUnnamedBitfield())
677 ++InitializableMembers;
679 if (structDecl->isUnion())
680 return std::min(InitializableMembers, 1);
681 return InitializableMembers - structDecl->hasFlexibleArrayMember();
684 /// Check whether the range of the initializer \p ParentIList from element
685 /// \p Index onwards can be used to initialize an object of type \p T. Update
686 /// \p Index to indicate how many elements of the list were consumed.
688 /// This also fills in \p StructuredList, from element \p StructuredIndex
689 /// onwards, with the fully-braced, desugared form of the initialization.
690 void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity,
691 InitListExpr *ParentIList,
692 QualType T, unsigned &Index,
693 InitListExpr *StructuredList,
694 unsigned &StructuredIndex) {
697 if (T->isArrayType())
698 maxElements = numArrayElements(T);
699 else if (T->isRecordType())
700 maxElements = numStructUnionElements(T);
701 else if (T->isVectorType())
702 maxElements = T->getAs<VectorType>()->getNumElements();
704 llvm_unreachable("CheckImplicitInitList(): Illegal type");
706 if (maxElements == 0) {
708 SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(),
709 diag::err_implicit_empty_initializer);
715 // Build a structured initializer list corresponding to this subobject.
716 InitListExpr *StructuredSubobjectInitList
717 = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList,
719 SourceRange(ParentIList->getInit(Index)->getLocStart(),
720 ParentIList->getSourceRange().getEnd()));
721 unsigned StructuredSubobjectInitIndex = 0;
723 // Check the element types and build the structural subobject.
724 unsigned StartIndex = Index;
725 CheckListElementTypes(Entity, ParentIList, T,
726 /*SubobjectIsDesignatorContext=*/false, Index,
727 StructuredSubobjectInitList,
728 StructuredSubobjectInitIndex);
731 StructuredSubobjectInitList->setType(T);
733 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1);
734 // Update the structured sub-object initializer so that it's ending
735 // range corresponds with the end of the last initializer it used.
736 if (EndIndex < ParentIList->getNumInits()) {
737 SourceLocation EndLoc
738 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd();
739 StructuredSubobjectInitList->setRBraceLoc(EndLoc);
742 // Complain about missing braces.
743 if (T->isArrayType() || T->isRecordType()) {
744 SemaRef.Diag(StructuredSubobjectInitList->getLocStart(),
745 diag::warn_missing_braces)
746 << StructuredSubobjectInitList->getSourceRange()
747 << FixItHint::CreateInsertion(
748 StructuredSubobjectInitList->getLocStart(), "{")
749 << FixItHint::CreateInsertion(
750 SemaRef.getLocForEndOfToken(
751 StructuredSubobjectInitList->getLocEnd()),
757 /// Warn that \p Entity was of scalar type and was initialized by a
758 /// single-element braced initializer list.
759 static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
760 SourceRange Braces) {
761 // Don't warn during template instantiation. If the initialization was
762 // non-dependent, we warned during the initial parse; otherwise, the
763 // type might not be scalar in some uses of the template.
764 if (!S.ActiveTemplateInstantiations.empty())
769 switch (Entity.getKind()) {
770 case InitializedEntity::EK_VectorElement:
771 case InitializedEntity::EK_ComplexElement:
772 case InitializedEntity::EK_ArrayElement:
773 case InitializedEntity::EK_Parameter:
774 case InitializedEntity::EK_Parameter_CF_Audited:
775 case InitializedEntity::EK_Result:
776 // Extra braces here are suspicious.
777 DiagID = diag::warn_braces_around_scalar_init;
780 case InitializedEntity::EK_Member:
781 // Warn on aggregate initialization but not on ctor init list or
782 // default member initializer.
783 if (Entity.getParent())
784 DiagID = diag::warn_braces_around_scalar_init;
787 case InitializedEntity::EK_Variable:
788 case InitializedEntity::EK_LambdaCapture:
789 // No warning, might be direct-list-initialization.
790 // FIXME: Should we warn for copy-list-initialization in these cases?
793 case InitializedEntity::EK_New:
794 case InitializedEntity::EK_Temporary:
795 case InitializedEntity::EK_CompoundLiteralInit:
796 // No warning, braces are part of the syntax of the underlying construct.
799 case InitializedEntity::EK_RelatedResult:
800 // No warning, we already warned when initializing the result.
803 case InitializedEntity::EK_Exception:
804 case InitializedEntity::EK_Base:
805 case InitializedEntity::EK_Delegating:
806 case InitializedEntity::EK_BlockElement:
807 llvm_unreachable("unexpected braced scalar init");
811 S.Diag(Braces.getBegin(), DiagID)
813 << FixItHint::CreateRemoval(Braces.getBegin())
814 << FixItHint::CreateRemoval(Braces.getEnd());
819 /// Check whether the initializer \p IList (that was written with explicit
820 /// braces) can be used to initialize an object of type \p T.
822 /// This also fills in \p StructuredList with the fully-braced, desugared
823 /// form of the initialization.
824 void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity,
825 InitListExpr *IList, QualType &T,
826 InitListExpr *StructuredList,
827 bool TopLevelObject) {
829 SyntacticToSemantic[IList] = StructuredList;
830 StructuredList->setSyntacticForm(IList);
833 unsigned Index = 0, StructuredIndex = 0;
834 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true,
835 Index, StructuredList, StructuredIndex, TopLevelObject);
838 if (!ExprTy->isArrayType())
839 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context);
840 IList->setType(ExprTy);
841 StructuredList->setType(ExprTy);
846 if (Index < IList->getNumInits()) {
847 // We have leftover initializers
849 if (SemaRef.getLangOpts().CPlusPlus ||
850 (SemaRef.getLangOpts().OpenCL &&
851 IList->getType()->isVectorType())) {
857 if (StructuredIndex == 1 &&
858 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) ==
860 unsigned DK = diag::ext_excess_initializers_in_char_array_initializer;
861 if (SemaRef.getLangOpts().CPlusPlus) {
862 DK = diag::err_excess_initializers_in_char_array_initializer;
866 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK)
867 << IList->getInit(Index)->getSourceRange();
868 } else if (!T->isIncompleteType()) {
869 // Don't complain for incomplete types, since we'll get an error
871 QualType CurrentObjectType = StructuredList->getType();
873 CurrentObjectType->isArrayType()? 0 :
874 CurrentObjectType->isVectorType()? 1 :
875 CurrentObjectType->isScalarType()? 2 :
876 CurrentObjectType->isUnionType()? 3 :
879 unsigned DK = diag::ext_excess_initializers;
880 if (SemaRef.getLangOpts().CPlusPlus) {
881 DK = diag::err_excess_initializers;
884 if (SemaRef.getLangOpts().OpenCL && initKind == 1) {
885 DK = diag::err_excess_initializers;
889 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK)
890 << initKind << IList->getInit(Index)->getSourceRange();
894 if (!VerifyOnly && T->isScalarType() &&
895 IList->getNumInits() == 1 && !isa<InitListExpr>(IList->getInit(0)))
896 warnBracedScalarInit(SemaRef, Entity, IList->getSourceRange());
899 void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity,
902 bool SubobjectIsDesignatorContext,
904 InitListExpr *StructuredList,
905 unsigned &StructuredIndex,
906 bool TopLevelObject) {
907 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) {
908 // Explicitly braced initializer for complex type can be real+imaginary
910 CheckComplexType(Entity, IList, DeclType, Index,
911 StructuredList, StructuredIndex);
912 } else if (DeclType->isScalarType()) {
913 CheckScalarType(Entity, IList, DeclType, Index,
914 StructuredList, StructuredIndex);
915 } else if (DeclType->isVectorType()) {
916 CheckVectorType(Entity, IList, DeclType, Index,
917 StructuredList, StructuredIndex);
918 } else if (DeclType->isRecordType()) {
919 assert(DeclType->isAggregateType() &&
920 "non-aggregate records should be handed in CheckSubElementType");
921 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
922 CheckStructUnionTypes(Entity, IList, DeclType, RD->field_begin(),
923 SubobjectIsDesignatorContext, Index,
924 StructuredList, StructuredIndex,
926 } else if (DeclType->isArrayType()) {
928 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()),
930 CheckArrayType(Entity, IList, DeclType, Zero,
931 SubobjectIsDesignatorContext, Index,
932 StructuredList, StructuredIndex);
933 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) {
934 // This type is invalid, issue a diagnostic.
937 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type)
940 } else if (DeclType->isReferenceType()) {
941 CheckReferenceType(Entity, IList, DeclType, Index,
942 StructuredList, StructuredIndex);
943 } else if (DeclType->isObjCObjectType()) {
945 SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class)
950 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type)
956 void InitListChecker::CheckSubElementType(const InitializedEntity &Entity,
960 InitListExpr *StructuredList,
961 unsigned &StructuredIndex) {
962 Expr *expr = IList->getInit(Index);
964 if (ElemType->isReferenceType())
965 return CheckReferenceType(Entity, IList, ElemType, Index,
966 StructuredList, StructuredIndex);
968 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) {
969 if (!SemaRef.getLangOpts().CPlusPlus) {
970 InitListExpr *InnerStructuredList
971 = getStructuredSubobjectInit(IList, Index, ElemType,
972 StructuredList, StructuredIndex,
973 SubInitList->getSourceRange());
974 CheckExplicitInitList(Entity, SubInitList, ElemType,
975 InnerStructuredList);
980 // C++ initialization is handled later.
981 } else if (isa<ImplicitValueInitExpr>(expr)) {
982 // This happens during template instantiation when we see an InitListExpr
983 // that we've already checked once.
984 assert(SemaRef.Context.hasSameType(expr->getType(), ElemType) &&
985 "found implicit initialization for the wrong type");
987 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
992 if (SemaRef.getLangOpts().CPlusPlus) {
993 // C++ [dcl.init.aggr]p2:
994 // Each member is copy-initialized from the corresponding
995 // initializer-clause.
997 // FIXME: Better EqualLoc?
998 InitializationKind Kind =
999 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation());
1000 InitializationSequence Seq(SemaRef, Entity, Kind, expr,
1001 /*TopLevelOfInitList*/ true);
1003 // C++14 [dcl.init.aggr]p13:
1004 // If the assignment-expression can initialize a member, the member is
1005 // initialized. Otherwise [...] brace elision is assumed
1007 // Brace elision is never performed if the element is not an
1008 // assignment-expression.
1009 if (Seq || isa<InitListExpr>(expr)) {
1012 Seq.Perform(SemaRef, Entity, Kind, expr);
1013 if (Result.isInvalid())
1016 UpdateStructuredListElement(StructuredList, StructuredIndex,
1017 Result.getAs<Expr>());
1024 // Fall through for subaggregate initialization
1025 } else if (ElemType->isScalarType() || ElemType->isAtomicType()) {
1026 // FIXME: Need to handle atomic aggregate types with implicit init lists.
1027 return CheckScalarType(Entity, IList, ElemType, Index,
1028 StructuredList, StructuredIndex);
1029 } else if (const ArrayType *arrayType =
1030 SemaRef.Context.getAsArrayType(ElemType)) {
1031 // arrayType can be incomplete if we're initializing a flexible
1032 // array member. There's nothing we can do with the completed
1033 // type here, though.
1035 if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) {
1037 CheckStringInit(expr, ElemType, arrayType, SemaRef);
1038 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1044 // Fall through for subaggregate initialization.
1047 assert((ElemType->isRecordType() || ElemType->isVectorType()) &&
1052 // The initializer for a structure or union object that has
1053 // automatic storage duration shall be either an initializer
1054 // list as described below, or a single expression that has
1055 // compatible structure or union type. In the latter case, the
1056 // initial value of the object, including unnamed members, is
1057 // that of the expression.
1058 ExprResult ExprRes = expr;
1059 if (SemaRef.CheckSingleAssignmentConstraints(
1060 ElemType, ExprRes, !VerifyOnly) != Sema::Incompatible) {
1061 if (ExprRes.isInvalid())
1064 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.get());
1065 if (ExprRes.isInvalid())
1068 UpdateStructuredListElement(StructuredList, StructuredIndex,
1069 ExprRes.getAs<Expr>());
1074 // Fall through for subaggregate initialization
1077 // C++ [dcl.init.aggr]p12:
1079 // [...] Otherwise, if the member is itself a non-empty
1080 // subaggregate, brace elision is assumed and the initializer is
1081 // considered for the initialization of the first member of
1082 // the subaggregate.
1083 if (!SemaRef.getLangOpts().OpenCL &&
1084 (ElemType->isAggregateType() || ElemType->isVectorType())) {
1085 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList,
1090 // We cannot initialize this element, so let
1091 // PerformCopyInitialization produce the appropriate diagnostic.
1092 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), expr,
1093 /*TopLevelOfInitList=*/true);
1101 void InitListChecker::CheckComplexType(const InitializedEntity &Entity,
1102 InitListExpr *IList, QualType DeclType,
1104 InitListExpr *StructuredList,
1105 unsigned &StructuredIndex) {
1106 assert(Index == 0 && "Index in explicit init list must be zero");
1108 // As an extension, clang supports complex initializers, which initialize
1109 // a complex number component-wise. When an explicit initializer list for
1110 // a complex number contains two two initializers, this extension kicks in:
1111 // it exepcts the initializer list to contain two elements convertible to
1112 // the element type of the complex type. The first element initializes
1113 // the real part, and the second element intitializes the imaginary part.
1115 if (IList->getNumInits() != 2)
1116 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1119 // This is an extension in C. (The builtin _Complex type does not exist
1120 // in the C++ standard.)
1121 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly)
1122 SemaRef.Diag(IList->getLocStart(), diag::ext_complex_component_init)
1123 << IList->getSourceRange();
1125 // Initialize the complex number.
1126 QualType elementType = DeclType->getAs<ComplexType>()->getElementType();
1127 InitializedEntity ElementEntity =
1128 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1130 for (unsigned i = 0; i < 2; ++i) {
1131 ElementEntity.setElementIndex(Index);
1132 CheckSubElementType(ElementEntity, IList, elementType, Index,
1133 StructuredList, StructuredIndex);
1138 void InitListChecker::CheckScalarType(const InitializedEntity &Entity,
1139 InitListExpr *IList, QualType DeclType,
1141 InitListExpr *StructuredList,
1142 unsigned &StructuredIndex) {
1143 if (Index >= IList->getNumInits()) {
1145 SemaRef.Diag(IList->getLocStart(),
1146 SemaRef.getLangOpts().CPlusPlus11 ?
1147 diag::warn_cxx98_compat_empty_scalar_initializer :
1148 diag::err_empty_scalar_initializer)
1149 << IList->getSourceRange();
1150 hadError = !SemaRef.getLangOpts().CPlusPlus11;
1156 Expr *expr = IList->getInit(Index);
1157 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) {
1158 // FIXME: This is invalid, and accepting it causes overload resolution
1159 // to pick the wrong overload in some corner cases.
1161 SemaRef.Diag(SubIList->getLocStart(),
1162 diag::ext_many_braces_around_scalar_init)
1163 << SubIList->getSourceRange();
1165 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList,
1168 } else if (isa<DesignatedInitExpr>(expr)) {
1170 SemaRef.Diag(expr->getLocStart(),
1171 diag::err_designator_for_scalar_init)
1172 << DeclType << expr->getSourceRange();
1180 if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
1187 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), expr,
1188 /*TopLevelOfInitList=*/true);
1190 Expr *ResultExpr = nullptr;
1192 if (Result.isInvalid())
1193 hadError = true; // types weren't compatible.
1195 ResultExpr = Result.getAs<Expr>();
1197 if (ResultExpr != expr) {
1198 // The type was promoted, update initializer list.
1199 IList->setInit(Index, ResultExpr);
1205 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1209 void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
1210 InitListExpr *IList, QualType DeclType,
1212 InitListExpr *StructuredList,
1213 unsigned &StructuredIndex) {
1214 if (Index >= IList->getNumInits()) {
1215 // FIXME: It would be wonderful if we could point at the actual member. In
1216 // general, it would be useful to pass location information down the stack,
1217 // so that we know the location (or decl) of the "current object" being
1220 SemaRef.Diag(IList->getLocStart(),
1221 diag::err_init_reference_member_uninitialized)
1223 << IList->getSourceRange();
1230 Expr *expr = IList->getInit(Index);
1231 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) {
1233 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list)
1234 << DeclType << IList->getSourceRange();
1242 if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
1249 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), expr,
1250 /*TopLevelOfInitList=*/true);
1252 if (Result.isInvalid())
1255 expr = Result.getAs<Expr>();
1256 IList->setInit(Index, expr);
1261 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1265 void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
1266 InitListExpr *IList, QualType DeclType,
1268 InitListExpr *StructuredList,
1269 unsigned &StructuredIndex) {
1270 const VectorType *VT = DeclType->getAs<VectorType>();
1271 unsigned maxElements = VT->getNumElements();
1272 unsigned numEltsInit = 0;
1273 QualType elementType = VT->getElementType();
1275 if (Index >= IList->getNumInits()) {
1276 // Make sure the element type can be value-initialized.
1278 CheckEmptyInitializable(
1279 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1280 IList->getLocEnd());
1284 if (!SemaRef.getLangOpts().OpenCL) {
1285 // If the initializing element is a vector, try to copy-initialize
1286 // instead of breaking it apart (which is doomed to failure anyway).
1287 Expr *Init = IList->getInit(Index);
1288 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) {
1290 if (!SemaRef.CanPerformCopyInitialization(Entity, Init))
1297 SemaRef.PerformCopyInitialization(Entity, Init->getLocStart(), Init,
1298 /*TopLevelOfInitList=*/true);
1300 Expr *ResultExpr = nullptr;
1301 if (Result.isInvalid())
1302 hadError = true; // types weren't compatible.
1304 ResultExpr = Result.getAs<Expr>();
1306 if (ResultExpr != Init) {
1307 // The type was promoted, update initializer list.
1308 IList->setInit(Index, ResultExpr);
1314 UpdateStructuredListElement(StructuredList, StructuredIndex,
1320 InitializedEntity ElementEntity =
1321 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1323 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
1324 // Don't attempt to go past the end of the init list
1325 if (Index >= IList->getNumInits()) {
1327 CheckEmptyInitializable(ElementEntity, IList->getLocEnd());
1331 ElementEntity.setElementIndex(Index);
1332 CheckSubElementType(ElementEntity, IList, elementType, Index,
1333 StructuredList, StructuredIndex);
1339 bool isBigEndian = SemaRef.Context.getTargetInfo().isBigEndian();
1340 const VectorType *T = Entity.getType()->getAs<VectorType>();
1341 if (isBigEndian && (T->getVectorKind() == VectorType::NeonVector ||
1342 T->getVectorKind() == VectorType::NeonPolyVector)) {
1343 // The ability to use vector initializer lists is a GNU vector extension
1344 // and is unrelated to the NEON intrinsics in arm_neon.h. On little
1345 // endian machines it works fine, however on big endian machines it
1346 // exhibits surprising behaviour:
1348 // uint32x2_t x = {42, 64};
1349 // return vget_lane_u32(x, 0); // Will return 64.
1351 // Because of this, explicitly call out that it is non-portable.
1353 SemaRef.Diag(IList->getLocStart(),
1354 diag::warn_neon_vector_initializer_non_portable);
1356 const char *typeCode;
1357 unsigned typeSize = SemaRef.Context.getTypeSize(elementType);
1359 if (elementType->isFloatingType())
1361 else if (elementType->isSignedIntegerType())
1363 else if (elementType->isUnsignedIntegerType())
1366 llvm_unreachable("Invalid element type!");
1368 SemaRef.Diag(IList->getLocStart(),
1369 SemaRef.Context.getTypeSize(VT) > 64 ?
1370 diag::note_neon_vector_initializer_non_portable_q :
1371 diag::note_neon_vector_initializer_non_portable)
1372 << typeCode << typeSize;
1378 InitializedEntity ElementEntity =
1379 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1381 // OpenCL initializers allows vectors to be constructed from vectors.
1382 for (unsigned i = 0; i < maxElements; ++i) {
1383 // Don't attempt to go past the end of the init list
1384 if (Index >= IList->getNumInits())
1387 ElementEntity.setElementIndex(Index);
1389 QualType IType = IList->getInit(Index)->getType();
1390 if (!IType->isVectorType()) {
1391 CheckSubElementType(ElementEntity, IList, elementType, Index,
1392 StructuredList, StructuredIndex);
1396 const VectorType *IVT = IType->getAs<VectorType>();
1397 unsigned numIElts = IVT->getNumElements();
1399 if (IType->isExtVectorType())
1400 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts);
1402 VecType = SemaRef.Context.getVectorType(elementType, numIElts,
1403 IVT->getVectorKind());
1404 CheckSubElementType(ElementEntity, IList, VecType, Index,
1405 StructuredList, StructuredIndex);
1406 numEltsInit += numIElts;
1410 // OpenCL requires all elements to be initialized.
1411 if (numEltsInit != maxElements) {
1413 SemaRef.Diag(IList->getLocStart(),
1414 diag::err_vector_incorrect_num_initializers)
1415 << (numEltsInit < maxElements) << maxElements << numEltsInit;
1420 void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
1421 InitListExpr *IList, QualType &DeclType,
1422 llvm::APSInt elementIndex,
1423 bool SubobjectIsDesignatorContext,
1425 InitListExpr *StructuredList,
1426 unsigned &StructuredIndex) {
1427 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
1429 // Check for the special-case of initializing an array with a string.
1430 if (Index < IList->getNumInits()) {
1431 if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
1433 // We place the string literal directly into the resulting
1434 // initializer list. This is the only place where the structure
1435 // of the structured initializer list doesn't match exactly,
1436 // because doing so would involve allocating one character
1437 // constant for each string.
1439 CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef);
1440 UpdateStructuredListElement(StructuredList, StructuredIndex,
1441 IList->getInit(Index));
1442 StructuredList->resizeInits(SemaRef.Context, StructuredIndex);
1448 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) {
1449 // Check for VLAs; in standard C it would be possible to check this
1450 // earlier, but I don't know where clang accepts VLAs (gcc accepts
1451 // them in all sorts of strange places).
1453 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(),
1454 diag::err_variable_object_no_init)
1455 << VAT->getSizeExpr()->getSourceRange();
1462 // We might know the maximum number of elements in advance.
1463 llvm::APSInt maxElements(elementIndex.getBitWidth(),
1464 elementIndex.isUnsigned());
1465 bool maxElementsKnown = false;
1466 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) {
1467 maxElements = CAT->getSize();
1468 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth());
1469 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1470 maxElementsKnown = true;
1473 QualType elementType = arrayType->getElementType();
1474 while (Index < IList->getNumInits()) {
1475 Expr *Init = IList->getInit(Index);
1476 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1477 // If we're not the subobject that matches up with the '{' for
1478 // the designator, we shouldn't be handling the
1479 // designator. Return immediately.
1480 if (!SubobjectIsDesignatorContext)
1483 // Handle this designated initializer. elementIndex will be
1484 // updated to be the next array element we'll initialize.
1485 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1486 DeclType, nullptr, &elementIndex, Index,
1487 StructuredList, StructuredIndex, true,
1493 if (elementIndex.getBitWidth() > maxElements.getBitWidth())
1494 maxElements = maxElements.extend(elementIndex.getBitWidth());
1495 else if (elementIndex.getBitWidth() < maxElements.getBitWidth())
1496 elementIndex = elementIndex.extend(maxElements.getBitWidth());
1497 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1499 // If the array is of incomplete type, keep track of the number of
1500 // elements in the initializer.
1501 if (!maxElementsKnown && elementIndex > maxElements)
1502 maxElements = elementIndex;
1507 // If we know the maximum number of elements, and we've already
1508 // hit it, stop consuming elements in the initializer list.
1509 if (maxElementsKnown && elementIndex == maxElements)
1512 InitializedEntity ElementEntity =
1513 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex,
1515 // Check this element.
1516 CheckSubElementType(ElementEntity, IList, elementType, Index,
1517 StructuredList, StructuredIndex);
1520 // If the array is of incomplete type, keep track of the number of
1521 // elements in the initializer.
1522 if (!maxElementsKnown && elementIndex > maxElements)
1523 maxElements = elementIndex;
1525 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) {
1526 // If this is an incomplete array type, the actual type needs to
1527 // be calculated here.
1528 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned());
1529 if (maxElements == Zero) {
1530 // Sizing an array implicitly to zero is not allowed by ISO C,
1531 // but is supported by GNU.
1532 SemaRef.Diag(IList->getLocStart(),
1533 diag::ext_typecheck_zero_array_size);
1536 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements,
1537 ArrayType::Normal, 0);
1539 if (!hadError && VerifyOnly) {
1540 // Check if there are any members of the array that get value-initialized.
1541 // If so, check if doing that is possible.
1542 // FIXME: This needs to detect holes left by designated initializers too.
1543 if (maxElementsKnown && elementIndex < maxElements)
1544 CheckEmptyInitializable(InitializedEntity::InitializeElement(
1545 SemaRef.Context, 0, Entity),
1546 IList->getLocEnd());
1550 bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
1553 bool TopLevelObject) {
1554 // Handle GNU flexible array initializers.
1555 unsigned FlexArrayDiag;
1556 if (isa<InitListExpr>(InitExpr) &&
1557 cast<InitListExpr>(InitExpr)->getNumInits() == 0) {
1558 // Empty flexible array init always allowed as an extension
1559 FlexArrayDiag = diag::ext_flexible_array_init;
1560 } else if (SemaRef.getLangOpts().CPlusPlus) {
1561 // Disallow flexible array init in C++; it is not required for gcc
1562 // compatibility, and it needs work to IRGen correctly in general.
1563 FlexArrayDiag = diag::err_flexible_array_init;
1564 } else if (!TopLevelObject) {
1565 // Disallow flexible array init on non-top-level object
1566 FlexArrayDiag = diag::err_flexible_array_init;
1567 } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
1568 // Disallow flexible array init on anything which is not a variable.
1569 FlexArrayDiag = diag::err_flexible_array_init;
1570 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) {
1571 // Disallow flexible array init on local variables.
1572 FlexArrayDiag = diag::err_flexible_array_init;
1574 // Allow other cases.
1575 FlexArrayDiag = diag::ext_flexible_array_init;
1579 SemaRef.Diag(InitExpr->getLocStart(),
1581 << InitExpr->getLocStart();
1582 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
1586 return FlexArrayDiag != diag::ext_flexible_array_init;
1589 void InitListChecker::CheckStructUnionTypes(const InitializedEntity &Entity,
1590 InitListExpr *IList,
1592 RecordDecl::field_iterator Field,
1593 bool SubobjectIsDesignatorContext,
1595 InitListExpr *StructuredList,
1596 unsigned &StructuredIndex,
1597 bool TopLevelObject) {
1598 RecordDecl* structDecl = DeclType->getAs<RecordType>()->getDecl();
1600 // If the record is invalid, some of it's members are invalid. To avoid
1601 // confusion, we forgo checking the intializer for the entire record.
1602 if (structDecl->isInvalidDecl()) {
1603 // Assume it was supposed to consume a single initializer.
1609 if (DeclType->isUnionType() && IList->getNumInits() == 0) {
1610 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1612 // If there's a default initializer, use it.
1613 if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
1616 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
1617 Field != FieldEnd; ++Field) {
1618 if (Field->hasInClassInitializer()) {
1619 StructuredList->setInitializedFieldInUnion(*Field);
1620 // FIXME: Actually build a CXXDefaultInitExpr?
1626 // Value-initialize the first member of the union that isn't an unnamed
1628 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
1629 Field != FieldEnd; ++Field) {
1630 if (!Field->isUnnamedBitfield()) {
1632 CheckEmptyInitializable(
1633 InitializedEntity::InitializeMember(*Field, &Entity),
1634 IList->getLocEnd());
1636 StructuredList->setInitializedFieldInUnion(*Field);
1643 // If structDecl is a forward declaration, this loop won't do
1644 // anything except look at designated initializers; That's okay,
1645 // because an error should get printed out elsewhere. It might be
1646 // worthwhile to skip over the rest of the initializer, though.
1647 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1648 RecordDecl::field_iterator FieldEnd = RD->field_end();
1649 bool InitializedSomething = false;
1650 bool CheckForMissingFields = true;
1651 while (Index < IList->getNumInits()) {
1652 Expr *Init = IList->getInit(Index);
1654 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1655 // If we're not the subobject that matches up with the '{' for
1656 // the designator, we shouldn't be handling the
1657 // designator. Return immediately.
1658 if (!SubobjectIsDesignatorContext)
1661 // Handle this designated initializer. Field will be updated to
1662 // the next field that we'll be initializing.
1663 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1664 DeclType, &Field, nullptr, Index,
1665 StructuredList, StructuredIndex,
1666 true, TopLevelObject))
1669 InitializedSomething = true;
1671 // Disable check for missing fields when designators are used.
1672 // This matches gcc behaviour.
1673 CheckForMissingFields = false;
1677 if (Field == FieldEnd) {
1678 // We've run out of fields. We're done.
1682 // We've already initialized a member of a union. We're done.
1683 if (InitializedSomething && DeclType->isUnionType())
1686 // If we've hit the flexible array member at the end, we're done.
1687 if (Field->getType()->isIncompleteArrayType())
1690 if (Field->isUnnamedBitfield()) {
1691 // Don't initialize unnamed bitfields, e.g. "int : 20;"
1696 // Make sure we can use this declaration.
1699 InvalidUse = !SemaRef.CanUseDecl(*Field);
1701 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field,
1702 IList->getInit(Index)->getLocStart());
1710 InitializedEntity MemberEntity =
1711 InitializedEntity::InitializeMember(*Field, &Entity);
1712 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
1713 StructuredList, StructuredIndex);
1714 InitializedSomething = true;
1716 if (DeclType->isUnionType() && !VerifyOnly) {
1717 // Initialize the first field within the union.
1718 StructuredList->setInitializedFieldInUnion(*Field);
1724 // Emit warnings for missing struct field initializers.
1725 if (!VerifyOnly && InitializedSomething && CheckForMissingFields &&
1726 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() &&
1727 !DeclType->isUnionType()) {
1728 // It is possible we have one or more unnamed bitfields remaining.
1729 // Find first (if any) named field and emit warning.
1730 for (RecordDecl::field_iterator it = Field, end = RD->field_end();
1732 if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
1733 SemaRef.Diag(IList->getSourceRange().getEnd(),
1734 diag::warn_missing_field_initializers) << *it;
1740 // Check that any remaining fields can be value-initialized.
1741 if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() &&
1742 !Field->getType()->isIncompleteArrayType()) {
1743 // FIXME: Should check for holes left by designated initializers too.
1744 for (; Field != FieldEnd && !hadError; ++Field) {
1745 if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
1746 CheckEmptyInitializable(
1747 InitializedEntity::InitializeMember(*Field, &Entity),
1748 IList->getLocEnd());
1752 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() ||
1753 Index >= IList->getNumInits())
1756 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field,
1763 InitializedEntity MemberEntity =
1764 InitializedEntity::InitializeMember(*Field, &Entity);
1766 if (isa<InitListExpr>(IList->getInit(Index)))
1767 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
1768 StructuredList, StructuredIndex);
1770 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index,
1771 StructuredList, StructuredIndex);
1774 /// \brief Expand a field designator that refers to a member of an
1775 /// anonymous struct or union into a series of field designators that
1776 /// refers to the field within the appropriate subobject.
1778 static void ExpandAnonymousFieldDesignator(Sema &SemaRef,
1779 DesignatedInitExpr *DIE,
1781 IndirectFieldDecl *IndirectField) {
1782 typedef DesignatedInitExpr::Designator Designator;
1784 // Build the replacement designators.
1785 SmallVector<Designator, 4> Replacements;
1786 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(),
1787 PE = IndirectField->chain_end(); PI != PE; ++PI) {
1789 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
1790 DIE->getDesignator(DesigIdx)->getDotLoc(),
1791 DIE->getDesignator(DesigIdx)->getFieldLoc()));
1793 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
1794 SourceLocation(), SourceLocation()));
1795 assert(isa<FieldDecl>(*PI));
1796 Replacements.back().setField(cast<FieldDecl>(*PI));
1799 // Expand the current designator into the set of replacement
1800 // designators, so we have a full subobject path down to where the
1801 // member of the anonymous struct/union is actually stored.
1802 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0],
1803 &Replacements[0] + Replacements.size());
1806 static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef,
1807 DesignatedInitExpr *DIE) {
1808 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1;
1809 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs);
1810 for (unsigned I = 0; I < NumIndexExprs; ++I)
1811 IndexExprs[I] = DIE->getSubExpr(I + 1);
1812 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators_begin(),
1813 DIE->size(), IndexExprs,
1814 DIE->getEqualOrColonLoc(),
1815 DIE->usesGNUSyntax(), DIE->getInit());
1820 // Callback to only accept typo corrections that are for field members of
1821 // the given struct or union.
1822 class FieldInitializerValidatorCCC : public CorrectionCandidateCallback {
1824 explicit FieldInitializerValidatorCCC(RecordDecl *RD)
1827 bool ValidateCandidate(const TypoCorrection &candidate) override {
1828 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>();
1829 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record);
1838 /// @brief Check the well-formedness of a C99 designated initializer.
1840 /// Determines whether the designated initializer @p DIE, which
1841 /// resides at the given @p Index within the initializer list @p
1842 /// IList, is well-formed for a current object of type @p DeclType
1843 /// (C99 6.7.8). The actual subobject that this designator refers to
1844 /// within the current subobject is returned in either
1845 /// @p NextField or @p NextElementIndex (whichever is appropriate).
1847 /// @param IList The initializer list in which this designated
1848 /// initializer occurs.
1850 /// @param DIE The designated initializer expression.
1852 /// @param DesigIdx The index of the current designator.
1854 /// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17),
1855 /// into which the designation in @p DIE should refer.
1857 /// @param NextField If non-NULL and the first designator in @p DIE is
1858 /// a field, this will be set to the field declaration corresponding
1859 /// to the field named by the designator.
1861 /// @param NextElementIndex If non-NULL and the first designator in @p
1862 /// DIE is an array designator or GNU array-range designator, this
1863 /// will be set to the last index initialized by this designator.
1865 /// @param Index Index into @p IList where the designated initializer
1868 /// @param StructuredList The initializer list expression that
1869 /// describes all of the subobject initializers in the order they'll
1870 /// actually be initialized.
1872 /// @returns true if there was an error, false otherwise.
1874 InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity,
1875 InitListExpr *IList,
1876 DesignatedInitExpr *DIE,
1878 QualType &CurrentObjectType,
1879 RecordDecl::field_iterator *NextField,
1880 llvm::APSInt *NextElementIndex,
1882 InitListExpr *StructuredList,
1883 unsigned &StructuredIndex,
1884 bool FinishSubobjectInit,
1885 bool TopLevelObject) {
1886 if (DesigIdx == DIE->size()) {
1887 // Check the actual initialization for the designated object type.
1888 bool prevHadError = hadError;
1890 // Temporarily remove the designator expression from the
1891 // initializer list that the child calls see, so that we don't try
1892 // to re-process the designator.
1893 unsigned OldIndex = Index;
1894 IList->setInit(OldIndex, DIE->getInit());
1896 CheckSubElementType(Entity, IList, CurrentObjectType, Index,
1897 StructuredList, StructuredIndex);
1899 // Restore the designated initializer expression in the syntactic
1900 // form of the initializer list.
1901 if (IList->getInit(OldIndex) != DIE->getInit())
1902 DIE->setInit(IList->getInit(OldIndex));
1903 IList->setInit(OldIndex, DIE);
1905 return hadError && !prevHadError;
1908 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx);
1909 bool IsFirstDesignator = (DesigIdx == 0);
1911 assert((IsFirstDesignator || StructuredList) &&
1912 "Need a non-designated initializer list to start from");
1914 // Determine the structural initializer list that corresponds to the
1915 // current subobject.
1916 StructuredList = IsFirstDesignator? SyntacticToSemantic.lookup(IList)
1917 : getStructuredSubobjectInit(IList, Index, CurrentObjectType,
1918 StructuredList, StructuredIndex,
1919 SourceRange(D->getLocStart(),
1921 assert(StructuredList && "Expected a structured initializer list");
1924 if (D->isFieldDesignator()) {
1927 // If a designator has the form
1931 // then the current object (defined below) shall have
1932 // structure or union type and the identifier shall be the
1933 // name of a member of that type.
1934 const RecordType *RT = CurrentObjectType->getAs<RecordType>();
1936 SourceLocation Loc = D->getDotLoc();
1937 if (Loc.isInvalid())
1938 Loc = D->getFieldLoc();
1940 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr)
1941 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType;
1946 FieldDecl *KnownField = D->getField();
1948 IdentifierInfo *FieldName = D->getFieldName();
1949 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName);
1950 for (NamedDecl *ND : Lookup) {
1951 if (auto *FD = dyn_cast<FieldDecl>(ND)) {
1955 if (auto *IFD = dyn_cast<IndirectFieldDecl>(ND)) {
1956 // In verify mode, don't modify the original.
1958 DIE = CloneDesignatedInitExpr(SemaRef, DIE);
1959 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IFD);
1960 D = DIE->getDesignator(DesigIdx);
1961 KnownField = cast<FieldDecl>(*IFD->chain_begin());
1968 return true; // No typo correction when just trying this out.
1971 // Name lookup found something, but it wasn't a field.
1972 if (!Lookup.empty()) {
1973 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield)
1975 SemaRef.Diag(Lookup.front()->getLocation(),
1976 diag::note_field_designator_found);
1981 // Name lookup didn't find anything.
1982 // Determine whether this was a typo for another field name.
1983 if (TypoCorrection Corrected = SemaRef.CorrectTypo(
1984 DeclarationNameInfo(FieldName, D->getFieldLoc()),
1985 Sema::LookupMemberName, /*Scope=*/nullptr, /*SS=*/nullptr,
1986 llvm::make_unique<FieldInitializerValidatorCCC>(RT->getDecl()),
1987 Sema::CTK_ErrorRecovery, RT->getDecl())) {
1988 SemaRef.diagnoseTypo(
1990 SemaRef.PDiag(diag::err_field_designator_unknown_suggest)
1991 << FieldName << CurrentObjectType);
1992 KnownField = Corrected.getCorrectionDeclAs<FieldDecl>();
1995 // Typo correction didn't find anything.
1996 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown)
1997 << FieldName << CurrentObjectType;
2004 unsigned FieldIndex = 0;
2005 for (auto *FI : RT->getDecl()->fields()) {
2006 if (FI->isUnnamedBitfield())
2008 if (KnownField == FI)
2013 RecordDecl::field_iterator Field =
2014 RecordDecl::field_iterator(DeclContext::decl_iterator(KnownField));
2016 // All of the fields of a union are located at the same place in
2017 // the initializer list.
2018 if (RT->getDecl()->isUnion()) {
2021 FieldDecl *CurrentField = StructuredList->getInitializedFieldInUnion();
2022 if (CurrentField && CurrentField != *Field) {
2023 assert(StructuredList->getNumInits() == 1
2024 && "A union should never have more than one initializer!");
2026 // we're about to throw away an initializer, emit warning
2027 SemaRef.Diag(D->getFieldLoc(),
2028 diag::warn_initializer_overrides)
2029 << D->getSourceRange();
2030 Expr *ExistingInit = StructuredList->getInit(0);
2031 SemaRef.Diag(ExistingInit->getLocStart(),
2032 diag::note_previous_initializer)
2033 << /*FIXME:has side effects=*/0
2034 << ExistingInit->getSourceRange();
2036 // remove existing initializer
2037 StructuredList->resizeInits(SemaRef.Context, 0);
2038 StructuredList->setInitializedFieldInUnion(nullptr);
2041 StructuredList->setInitializedFieldInUnion(*Field);
2045 // Make sure we can use this declaration.
2048 InvalidUse = !SemaRef.CanUseDecl(*Field);
2050 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc());
2057 // Update the designator with the field declaration.
2058 D->setField(*Field);
2060 // Make sure that our non-designated initializer list has space
2061 // for a subobject corresponding to this field.
2062 if (FieldIndex >= StructuredList->getNumInits())
2063 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1);
2066 // This designator names a flexible array member.
2067 if (Field->getType()->isIncompleteArrayType()) {
2068 bool Invalid = false;
2069 if ((DesigIdx + 1) != DIE->size()) {
2070 // We can't designate an object within the flexible array
2071 // member (because GCC doesn't allow it).
2073 DesignatedInitExpr::Designator *NextD
2074 = DIE->getDesignator(DesigIdx + 1);
2075 SemaRef.Diag(NextD->getLocStart(),
2076 diag::err_designator_into_flexible_array_member)
2077 << SourceRange(NextD->getLocStart(),
2079 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2085 if (!hadError && !isa<InitListExpr>(DIE->getInit()) &&
2086 !isa<StringLiteral>(DIE->getInit())) {
2087 // The initializer is not an initializer list.
2089 SemaRef.Diag(DIE->getInit()->getLocStart(),
2090 diag::err_flexible_array_init_needs_braces)
2091 << DIE->getInit()->getSourceRange();
2092 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2098 // Check GNU flexible array initializer.
2099 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field,
2108 // Initialize the array.
2109 bool prevHadError = hadError;
2110 unsigned newStructuredIndex = FieldIndex;
2111 unsigned OldIndex = Index;
2112 IList->setInit(Index, DIE->getInit());
2114 InitializedEntity MemberEntity =
2115 InitializedEntity::InitializeMember(*Field, &Entity);
2116 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2117 StructuredList, newStructuredIndex);
2119 IList->setInit(OldIndex, DIE);
2120 if (hadError && !prevHadError) {
2125 StructuredIndex = FieldIndex;
2129 // Recurse to check later designated subobjects.
2130 QualType FieldType = Field->getType();
2131 unsigned newStructuredIndex = FieldIndex;
2133 InitializedEntity MemberEntity =
2134 InitializedEntity::InitializeMember(*Field, &Entity);
2135 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1,
2136 FieldType, nullptr, nullptr, Index,
2137 StructuredList, newStructuredIndex,
2142 // Find the position of the next field to be initialized in this
2147 // If this the first designator, our caller will continue checking
2148 // the rest of this struct/class/union subobject.
2149 if (IsFirstDesignator) {
2152 StructuredIndex = FieldIndex;
2156 if (!FinishSubobjectInit)
2159 // We've already initialized something in the union; we're done.
2160 if (RT->getDecl()->isUnion())
2163 // Check the remaining fields within this class/struct/union subobject.
2164 bool prevHadError = hadError;
2166 CheckStructUnionTypes(Entity, IList, CurrentObjectType, Field, false, Index,
2167 StructuredList, FieldIndex);
2168 return hadError && !prevHadError;
2173 // If a designator has the form
2175 // [ constant-expression ]
2177 // then the current object (defined below) shall have array
2178 // type and the expression shall be an integer constant
2179 // expression. If the array is of unknown size, any
2180 // nonnegative value is valid.
2182 // Additionally, cope with the GNU extension that permits
2183 // designators of the form
2185 // [ constant-expression ... constant-expression ]
2186 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType);
2189 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array)
2190 << CurrentObjectType;
2195 Expr *IndexExpr = nullptr;
2196 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex;
2197 if (D->isArrayDesignator()) {
2198 IndexExpr = DIE->getArrayIndex(*D);
2199 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context);
2200 DesignatedEndIndex = DesignatedStartIndex;
2202 assert(D->isArrayRangeDesignator() && "Need array-range designator");
2204 DesignatedStartIndex =
2205 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context);
2206 DesignatedEndIndex =
2207 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context);
2208 IndexExpr = DIE->getArrayRangeEnd(*D);
2210 // Codegen can't handle evaluating array range designators that have side
2211 // effects, because we replicate the AST value for each initialized element.
2212 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple
2213 // elements with something that has a side effect, so codegen can emit an
2214 // "error unsupported" error instead of miscompiling the app.
2215 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&&
2216 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly)
2217 FullyStructuredList->sawArrayRangeDesignator();
2220 if (isa<ConstantArrayType>(AT)) {
2221 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false);
2222 DesignatedStartIndex
2223 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth());
2224 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned());
2226 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth());
2227 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned());
2228 if (DesignatedEndIndex >= MaxElements) {
2230 SemaRef.Diag(IndexExpr->getLocStart(),
2231 diag::err_array_designator_too_large)
2232 << DesignatedEndIndex.toString(10) << MaxElements.toString(10)
2233 << IndexExpr->getSourceRange();
2238 // Make sure the bit-widths and signedness match.
2239 if (DesignatedStartIndex.getBitWidth() > DesignatedEndIndex.getBitWidth())
2241 = DesignatedEndIndex.extend(DesignatedStartIndex.getBitWidth());
2242 else if (DesignatedStartIndex.getBitWidth() <
2243 DesignatedEndIndex.getBitWidth())
2244 DesignatedStartIndex
2245 = DesignatedStartIndex.extend(DesignatedEndIndex.getBitWidth());
2246 DesignatedStartIndex.setIsUnsigned(true);
2247 DesignatedEndIndex.setIsUnsigned(true);
2250 if (!VerifyOnly && StructuredList->isStringLiteralInit()) {
2251 // We're modifying a string literal init; we have to decompose the string
2252 // so we can modify the individual characters.
2253 ASTContext &Context = SemaRef.Context;
2254 Expr *SubExpr = StructuredList->getInit(0)->IgnoreParens();
2256 // Compute the character type
2257 QualType CharTy = AT->getElementType();
2259 // Compute the type of the integer literals.
2260 QualType PromotedCharTy = CharTy;
2261 if (CharTy->isPromotableIntegerType())
2262 PromotedCharTy = Context.getPromotedIntegerType(CharTy);
2263 unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy);
2265 if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) {
2266 // Get the length of the string.
2267 uint64_t StrLen = SL->getLength();
2268 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2269 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2270 StructuredList->resizeInits(Context, StrLen);
2272 // Build a literal for each character in the string, and put them into
2274 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2275 llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i));
2276 Expr *Init = new (Context) IntegerLiteral(
2277 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2278 if (CharTy != PromotedCharTy)
2279 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2280 Init, nullptr, VK_RValue);
2281 StructuredList->updateInit(Context, i, Init);
2284 ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr);
2286 Context.getObjCEncodingForType(E->getEncodedType(), Str);
2288 // Get the length of the string.
2289 uint64_t StrLen = Str.size();
2290 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2291 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2292 StructuredList->resizeInits(Context, StrLen);
2294 // Build a literal for each character in the string, and put them into
2296 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2297 llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]);
2298 Expr *Init = new (Context) IntegerLiteral(
2299 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2300 if (CharTy != PromotedCharTy)
2301 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2302 Init, nullptr, VK_RValue);
2303 StructuredList->updateInit(Context, i, Init);
2308 // Make sure that our non-designated initializer list has space
2309 // for a subobject corresponding to this array element.
2311 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits())
2312 StructuredList->resizeInits(SemaRef.Context,
2313 DesignatedEndIndex.getZExtValue() + 1);
2315 // Repeatedly perform subobject initializations in the range
2316 // [DesignatedStartIndex, DesignatedEndIndex].
2318 // Move to the next designator
2319 unsigned ElementIndex = DesignatedStartIndex.getZExtValue();
2320 unsigned OldIndex = Index;
2322 InitializedEntity ElementEntity =
2323 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
2325 while (DesignatedStartIndex <= DesignatedEndIndex) {
2326 // Recurse to check later designated subobjects.
2327 QualType ElementType = AT->getElementType();
2330 ElementEntity.setElementIndex(ElementIndex);
2331 if (CheckDesignatedInitializer(ElementEntity, IList, DIE, DesigIdx + 1,
2332 ElementType, nullptr, nullptr, Index,
2333 StructuredList, ElementIndex,
2334 (DesignatedStartIndex == DesignatedEndIndex),
2338 // Move to the next index in the array that we'll be initializing.
2339 ++DesignatedStartIndex;
2340 ElementIndex = DesignatedStartIndex.getZExtValue();
2343 // If this the first designator, our caller will continue checking
2344 // the rest of this array subobject.
2345 if (IsFirstDesignator) {
2346 if (NextElementIndex)
2347 *NextElementIndex = DesignatedStartIndex;
2348 StructuredIndex = ElementIndex;
2352 if (!FinishSubobjectInit)
2355 // Check the remaining elements within this array subobject.
2356 bool prevHadError = hadError;
2357 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex,
2358 /*SubobjectIsDesignatorContext=*/false, Index,
2359 StructuredList, ElementIndex);
2360 return hadError && !prevHadError;
2363 // Get the structured initializer list for a subobject of type
2364 // @p CurrentObjectType.
2366 InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
2367 QualType CurrentObjectType,
2368 InitListExpr *StructuredList,
2369 unsigned StructuredIndex,
2370 SourceRange InitRange) {
2372 return nullptr; // No structured list in verification-only mode.
2373 Expr *ExistingInit = nullptr;
2374 if (!StructuredList)
2375 ExistingInit = SyntacticToSemantic.lookup(IList);
2376 else if (StructuredIndex < StructuredList->getNumInits())
2377 ExistingInit = StructuredList->getInit(StructuredIndex);
2379 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit))
2383 // We are creating an initializer list that initializes the
2384 // subobjects of the current object, but there was already an
2385 // initialization that completely initialized the current
2386 // subobject, e.g., by a compound literal:
2388 // struct X { int a, b; };
2389 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2391 // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
2392 // designated initializer re-initializes the whole
2393 // subobject [0], overwriting previous initializers.
2394 SemaRef.Diag(InitRange.getBegin(),
2395 diag::warn_subobject_initializer_overrides)
2397 SemaRef.Diag(ExistingInit->getLocStart(),
2398 diag::note_previous_initializer)
2399 << /*FIXME:has side effects=*/0
2400 << ExistingInit->getSourceRange();
2403 InitListExpr *Result
2404 = new (SemaRef.Context) InitListExpr(SemaRef.Context,
2405 InitRange.getBegin(), None,
2406 InitRange.getEnd());
2408 QualType ResultType = CurrentObjectType;
2409 if (!ResultType->isArrayType())
2410 ResultType = ResultType.getNonLValueExprType(SemaRef.Context);
2411 Result->setType(ResultType);
2413 // Pre-allocate storage for the structured initializer list.
2414 unsigned NumElements = 0;
2415 unsigned NumInits = 0;
2416 bool GotNumInits = false;
2417 if (!StructuredList) {
2418 NumInits = IList->getNumInits();
2420 } else if (Index < IList->getNumInits()) {
2421 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) {
2422 NumInits = SubList->getNumInits();
2427 if (const ArrayType *AType
2428 = SemaRef.Context.getAsArrayType(CurrentObjectType)) {
2429 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) {
2430 NumElements = CAType->getSize().getZExtValue();
2431 // Simple heuristic so that we don't allocate a very large
2432 // initializer with many empty entries at the end.
2433 if (GotNumInits && NumElements > NumInits)
2436 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>())
2437 NumElements = VType->getNumElements();
2438 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) {
2439 RecordDecl *RDecl = RType->getDecl();
2440 if (RDecl->isUnion())
2443 NumElements = std::distance(RDecl->field_begin(), RDecl->field_end());
2446 Result->reserveInits(SemaRef.Context, NumElements);
2448 // Link this new initializer list into the structured initializer
2451 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result);
2453 Result->setSyntacticForm(IList);
2454 SyntacticToSemantic[IList] = Result;
2460 /// Update the initializer at index @p StructuredIndex within the
2461 /// structured initializer list to the value @p expr.
2462 void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList,
2463 unsigned &StructuredIndex,
2465 // No structured initializer list to update
2466 if (!StructuredList)
2469 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context,
2470 StructuredIndex, expr)) {
2471 // This initializer overwrites a previous initializer. Warn.
2472 SemaRef.Diag(expr->getLocStart(),
2473 diag::warn_initializer_overrides)
2474 << expr->getSourceRange();
2475 SemaRef.Diag(PrevInit->getLocStart(),
2476 diag::note_previous_initializer)
2477 << /*FIXME:has side effects=*/0
2478 << PrevInit->getSourceRange();
2484 /// Check that the given Index expression is a valid array designator
2485 /// value. This is essentially just a wrapper around
2486 /// VerifyIntegerConstantExpression that also checks for negative values
2487 /// and produces a reasonable diagnostic if there is a
2488 /// failure. Returns the index expression, possibly with an implicit cast
2489 /// added, on success. If everything went okay, Value will receive the
2490 /// value of the constant expression.
2492 CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) {
2493 SourceLocation Loc = Index->getLocStart();
2495 // Make sure this is an integer constant expression.
2496 ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value);
2497 if (Result.isInvalid())
2500 if (Value.isSigned() && Value.isNegative())
2501 return S.Diag(Loc, diag::err_array_designator_negative)
2502 << Value.toString(10) << Index->getSourceRange();
2504 Value.setIsUnsigned(true);
2508 ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig,
2512 typedef DesignatedInitExpr::Designator ASTDesignator;
2514 bool Invalid = false;
2515 SmallVector<ASTDesignator, 32> Designators;
2516 SmallVector<Expr *, 32> InitExpressions;
2518 // Build designators and check array designator expressions.
2519 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) {
2520 const Designator &D = Desig.getDesignator(Idx);
2521 switch (D.getKind()) {
2522 case Designator::FieldDesignator:
2523 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(),
2527 case Designator::ArrayDesignator: {
2528 Expr *Index = static_cast<Expr *>(D.getArrayIndex());
2529 llvm::APSInt IndexValue;
2530 if (!Index->isTypeDependent() && !Index->isValueDependent())
2531 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).get();
2535 Designators.push_back(ASTDesignator(InitExpressions.size(),
2537 D.getRBracketLoc()));
2538 InitExpressions.push_back(Index);
2543 case Designator::ArrayRangeDesignator: {
2544 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart());
2545 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd());
2546 llvm::APSInt StartValue;
2547 llvm::APSInt EndValue;
2548 bool StartDependent = StartIndex->isTypeDependent() ||
2549 StartIndex->isValueDependent();
2550 bool EndDependent = EndIndex->isTypeDependent() ||
2551 EndIndex->isValueDependent();
2552 if (!StartDependent)
2554 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).get();
2556 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).get();
2558 if (!StartIndex || !EndIndex)
2561 // Make sure we're comparing values with the same bit width.
2562 if (StartDependent || EndDependent) {
2563 // Nothing to compute.
2564 } else if (StartValue.getBitWidth() > EndValue.getBitWidth())
2565 EndValue = EndValue.extend(StartValue.getBitWidth());
2566 else if (StartValue.getBitWidth() < EndValue.getBitWidth())
2567 StartValue = StartValue.extend(EndValue.getBitWidth());
2569 if (!StartDependent && !EndDependent && EndValue < StartValue) {
2570 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range)
2571 << StartValue.toString(10) << EndValue.toString(10)
2572 << StartIndex->getSourceRange() << EndIndex->getSourceRange();
2575 Designators.push_back(ASTDesignator(InitExpressions.size(),
2578 D.getRBracketLoc()));
2579 InitExpressions.push_back(StartIndex);
2580 InitExpressions.push_back(EndIndex);
2588 if (Invalid || Init.isInvalid())
2591 // Clear out the expressions within the designation.
2592 Desig.ClearExprs(*this);
2594 DesignatedInitExpr *DIE
2595 = DesignatedInitExpr::Create(Context,
2596 Designators.data(), Designators.size(),
2597 InitExpressions, Loc, GNUSyntax,
2598 Init.getAs<Expr>());
2600 if (!getLangOpts().C99)
2601 Diag(DIE->getLocStart(), diag::ext_designated_init)
2602 << DIE->getSourceRange();
2607 //===----------------------------------------------------------------------===//
2608 // Initialization entity
2609 //===----------------------------------------------------------------------===//
2611 InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index,
2612 const InitializedEntity &Parent)
2613 : Parent(&Parent), Index(Index)
2615 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) {
2616 Kind = EK_ArrayElement;
2617 Type = AT->getElementType();
2618 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) {
2619 Kind = EK_VectorElement;
2620 Type = VT->getElementType();
2622 const ComplexType *CT = Parent.getType()->getAs<ComplexType>();
2623 assert(CT && "Unexpected type");
2624 Kind = EK_ComplexElement;
2625 Type = CT->getElementType();
2630 InitializedEntity::InitializeBase(ASTContext &Context,
2631 const CXXBaseSpecifier *Base,
2632 bool IsInheritedVirtualBase) {
2633 InitializedEntity Result;
2634 Result.Kind = EK_Base;
2635 Result.Parent = nullptr;
2636 Result.Base = reinterpret_cast<uintptr_t>(Base);
2637 if (IsInheritedVirtualBase)
2638 Result.Base |= 0x01;
2640 Result.Type = Base->getType();
2644 DeclarationName InitializedEntity::getName() const {
2645 switch (getKind()) {
2647 case EK_Parameter_CF_Audited: {
2648 ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
2649 return (D ? D->getDeclName() : DeclarationName());
2654 return VariableOrMember->getDeclName();
2656 case EK_LambdaCapture:
2657 return DeclarationName(Capture.VarID);
2665 case EK_ArrayElement:
2666 case EK_VectorElement:
2667 case EK_ComplexElement:
2668 case EK_BlockElement:
2669 case EK_CompoundLiteralInit:
2670 case EK_RelatedResult:
2671 return DeclarationName();
2674 llvm_unreachable("Invalid EntityKind!");
2677 DeclaratorDecl *InitializedEntity::getDecl() const {
2678 switch (getKind()) {
2681 return VariableOrMember;
2684 case EK_Parameter_CF_Audited:
2685 return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
2693 case EK_ArrayElement:
2694 case EK_VectorElement:
2695 case EK_ComplexElement:
2696 case EK_BlockElement:
2697 case EK_LambdaCapture:
2698 case EK_CompoundLiteralInit:
2699 case EK_RelatedResult:
2703 llvm_unreachable("Invalid EntityKind!");
2706 bool InitializedEntity::allowsNRVO() const {
2707 switch (getKind()) {
2710 return LocAndNRVO.NRVO;
2714 case EK_Parameter_CF_Audited:
2718 case EK_CompoundLiteralInit:
2721 case EK_ArrayElement:
2722 case EK_VectorElement:
2723 case EK_ComplexElement:
2724 case EK_BlockElement:
2725 case EK_LambdaCapture:
2726 case EK_RelatedResult:
2733 unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const {
2734 assert(getParent() != this);
2735 unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0;
2736 for (unsigned I = 0; I != Depth; ++I)
2739 switch (getKind()) {
2740 case EK_Variable: OS << "Variable"; break;
2741 case EK_Parameter: OS << "Parameter"; break;
2742 case EK_Parameter_CF_Audited: OS << "CF audited function Parameter";
2744 case EK_Result: OS << "Result"; break;
2745 case EK_Exception: OS << "Exception"; break;
2746 case EK_Member: OS << "Member"; break;
2747 case EK_New: OS << "New"; break;
2748 case EK_Temporary: OS << "Temporary"; break;
2749 case EK_CompoundLiteralInit: OS << "CompoundLiteral";break;
2750 case EK_RelatedResult: OS << "RelatedResult"; break;
2751 case EK_Base: OS << "Base"; break;
2752 case EK_Delegating: OS << "Delegating"; break;
2753 case EK_ArrayElement: OS << "ArrayElement " << Index; break;
2754 case EK_VectorElement: OS << "VectorElement " << Index; break;
2755 case EK_ComplexElement: OS << "ComplexElement " << Index; break;
2756 case EK_BlockElement: OS << "Block"; break;
2757 case EK_LambdaCapture:
2758 OS << "LambdaCapture ";
2759 OS << DeclarationName(Capture.VarID);
2763 if (Decl *D = getDecl()) {
2765 cast<NamedDecl>(D)->printQualifiedName(OS);
2768 OS << " '" << getType().getAsString() << "'\n";
2773 void InitializedEntity::dump() const {
2774 dumpImpl(llvm::errs());
2777 //===----------------------------------------------------------------------===//
2778 // Initialization sequence
2779 //===----------------------------------------------------------------------===//
2781 void InitializationSequence::Step::Destroy() {
2783 case SK_ResolveAddressOfOverloadedFunction:
2784 case SK_CastDerivedToBaseRValue:
2785 case SK_CastDerivedToBaseXValue:
2786 case SK_CastDerivedToBaseLValue:
2787 case SK_BindReference:
2788 case SK_BindReferenceToTemporary:
2789 case SK_ExtraneousCopyToTemporary:
2790 case SK_UserConversion:
2791 case SK_QualificationConversionRValue:
2792 case SK_QualificationConversionXValue:
2793 case SK_QualificationConversionLValue:
2794 case SK_AtomicConversion:
2795 case SK_LValueToRValue:
2796 case SK_ListInitialization:
2797 case SK_UnwrapInitList:
2798 case SK_RewrapInitList:
2799 case SK_ConstructorInitialization:
2800 case SK_ConstructorInitializationFromList:
2801 case SK_ZeroInitialization:
2802 case SK_CAssignment:
2804 case SK_ObjCObjectConversion:
2806 case SK_ParenthesizedArrayInit:
2807 case SK_PassByIndirectCopyRestore:
2808 case SK_PassByIndirectRestore:
2809 case SK_ProduceObjCObject:
2810 case SK_StdInitializerList:
2811 case SK_StdInitializerListConstructorCall:
2812 case SK_OCLSamplerInit:
2813 case SK_OCLZeroEvent:
2816 case SK_ConversionSequence:
2817 case SK_ConversionSequenceNoNarrowing:
2822 bool InitializationSequence::isDirectReferenceBinding() const {
2823 return !Steps.empty() && Steps.back().Kind == SK_BindReference;
2826 bool InitializationSequence::isAmbiguous() const {
2830 switch (getFailureKind()) {
2831 case FK_TooManyInitsForReference:
2832 case FK_ArrayNeedsInitList:
2833 case FK_ArrayNeedsInitListOrStringLiteral:
2834 case FK_ArrayNeedsInitListOrWideStringLiteral:
2835 case FK_NarrowStringIntoWideCharArray:
2836 case FK_WideStringIntoCharArray:
2837 case FK_IncompatWideStringIntoWideChar:
2838 case FK_AddressOfOverloadFailed: // FIXME: Could do better
2839 case FK_NonConstLValueReferenceBindingToTemporary:
2840 case FK_NonConstLValueReferenceBindingToUnrelated:
2841 case FK_RValueReferenceBindingToLValue:
2842 case FK_ReferenceInitDropsQualifiers:
2843 case FK_ReferenceInitFailed:
2844 case FK_ConversionFailed:
2845 case FK_ConversionFromPropertyFailed:
2846 case FK_TooManyInitsForScalar:
2847 case FK_ReferenceBindingToInitList:
2848 case FK_InitListBadDestinationType:
2849 case FK_DefaultInitOfConst:
2851 case FK_ArrayTypeMismatch:
2852 case FK_NonConstantArrayInit:
2853 case FK_ListInitializationFailed:
2854 case FK_VariableLengthArrayHasInitializer:
2855 case FK_PlaceholderType:
2856 case FK_ExplicitConstructor:
2859 case FK_ReferenceInitOverloadFailed:
2860 case FK_UserConversionOverloadFailed:
2861 case FK_ConstructorOverloadFailed:
2862 case FK_ListConstructorOverloadFailed:
2863 return FailedOverloadResult == OR_Ambiguous;
2866 llvm_unreachable("Invalid EntityKind!");
2869 bool InitializationSequence::isConstructorInitialization() const {
2870 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization;
2874 InitializationSequence
2875 ::AddAddressOverloadResolutionStep(FunctionDecl *Function,
2876 DeclAccessPair Found,
2877 bool HadMultipleCandidates) {
2879 S.Kind = SK_ResolveAddressOfOverloadedFunction;
2880 S.Type = Function->getType();
2881 S.Function.HadMultipleCandidates = HadMultipleCandidates;
2882 S.Function.Function = Function;
2883 S.Function.FoundDecl = Found;
2887 void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType,
2891 case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break;
2892 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break;
2893 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break;
2899 void InitializationSequence::AddReferenceBindingStep(QualType T,
2900 bool BindingTemporary) {
2902 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference;
2907 void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) {
2909 S.Kind = SK_ExtraneousCopyToTemporary;
2915 InitializationSequence::AddUserConversionStep(FunctionDecl *Function,
2916 DeclAccessPair FoundDecl,
2918 bool HadMultipleCandidates) {
2920 S.Kind = SK_UserConversion;
2922 S.Function.HadMultipleCandidates = HadMultipleCandidates;
2923 S.Function.Function = Function;
2924 S.Function.FoundDecl = FoundDecl;
2928 void InitializationSequence::AddQualificationConversionStep(QualType Ty,
2931 S.Kind = SK_QualificationConversionRValue; // work around a gcc warning
2934 S.Kind = SK_QualificationConversionRValue;
2937 S.Kind = SK_QualificationConversionXValue;
2940 S.Kind = SK_QualificationConversionLValue;
2947 void InitializationSequence::AddAtomicConversionStep(QualType Ty) {
2949 S.Kind = SK_AtomicConversion;
2954 void InitializationSequence::AddLValueToRValueStep(QualType Ty) {
2955 assert(!Ty.hasQualifiers() && "rvalues may not have qualifiers");
2958 S.Kind = SK_LValueToRValue;
2963 void InitializationSequence::AddConversionSequenceStep(
2964 const ImplicitConversionSequence &ICS, QualType T,
2965 bool TopLevelOfInitList) {
2967 S.Kind = TopLevelOfInitList ? SK_ConversionSequenceNoNarrowing
2968 : SK_ConversionSequence;
2970 S.ICS = new ImplicitConversionSequence(ICS);
2974 void InitializationSequence::AddListInitializationStep(QualType T) {
2976 S.Kind = SK_ListInitialization;
2982 InitializationSequence
2983 ::AddConstructorInitializationStep(CXXConstructorDecl *Constructor,
2984 AccessSpecifier Access,
2986 bool HadMultipleCandidates,
2987 bool FromInitList, bool AsInitList) {
2989 S.Kind = FromInitList ? AsInitList ? SK_StdInitializerListConstructorCall
2990 : SK_ConstructorInitializationFromList
2991 : SK_ConstructorInitialization;
2993 S.Function.HadMultipleCandidates = HadMultipleCandidates;
2994 S.Function.Function = Constructor;
2995 S.Function.FoundDecl = DeclAccessPair::make(Constructor, Access);
2999 void InitializationSequence::AddZeroInitializationStep(QualType T) {
3001 S.Kind = SK_ZeroInitialization;
3006 void InitializationSequence::AddCAssignmentStep(QualType T) {
3008 S.Kind = SK_CAssignment;
3013 void InitializationSequence::AddStringInitStep(QualType T) {
3015 S.Kind = SK_StringInit;
3020 void InitializationSequence::AddObjCObjectConversionStep(QualType T) {
3022 S.Kind = SK_ObjCObjectConversion;
3027 void InitializationSequence::AddArrayInitStep(QualType T) {
3029 S.Kind = SK_ArrayInit;
3034 void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) {
3036 S.Kind = SK_ParenthesizedArrayInit;
3041 void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type,
3044 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore
3045 : SK_PassByIndirectRestore);
3050 void InitializationSequence::AddProduceObjCObjectStep(QualType T) {
3052 S.Kind = SK_ProduceObjCObject;
3057 void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
3059 S.Kind = SK_StdInitializerList;
3064 void InitializationSequence::AddOCLSamplerInitStep(QualType T) {
3066 S.Kind = SK_OCLSamplerInit;
3071 void InitializationSequence::AddOCLZeroEventStep(QualType T) {
3073 S.Kind = SK_OCLZeroEvent;
3078 void InitializationSequence::RewrapReferenceInitList(QualType T,
3079 InitListExpr *Syntactic) {
3080 assert(Syntactic->getNumInits() == 1 &&
3081 "Can only rewrap trivial init lists.");
3083 S.Kind = SK_UnwrapInitList;
3084 S.Type = Syntactic->getInit(0)->getType();
3085 Steps.insert(Steps.begin(), S);
3087 S.Kind = SK_RewrapInitList;
3089 S.WrappingSyntacticList = Syntactic;
3093 void InitializationSequence::SetOverloadFailure(FailureKind Failure,
3094 OverloadingResult Result) {
3095 setSequenceKind(FailedSequence);
3096 this->Failure = Failure;
3097 this->FailedOverloadResult = Result;
3100 //===----------------------------------------------------------------------===//
3101 // Attempt initialization
3102 //===----------------------------------------------------------------------===//
3104 /// Tries to add a zero initializer. Returns true if that worked.
3106 maybeRecoverWithZeroInitialization(Sema &S, InitializationSequence &Sequence,
3107 const InitializedEntity &Entity) {
3108 if (Entity.getKind() != InitializedEntity::EK_Variable)
3111 VarDecl *VD = cast<VarDecl>(Entity.getDecl());
3112 if (VD->getInit() || VD->getLocEnd().isMacroID())
3115 QualType VariableTy = VD->getType().getCanonicalType();
3116 SourceLocation Loc = S.getLocForEndOfToken(VD->getLocEnd());
3117 std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
3118 if (!Init.empty()) {
3119 Sequence.AddZeroInitializationStep(Entity.getType());
3120 Sequence.SetZeroInitializationFixit(Init, Loc);
3126 static void MaybeProduceObjCObject(Sema &S,
3127 InitializationSequence &Sequence,
3128 const InitializedEntity &Entity) {
3129 if (!S.getLangOpts().ObjCAutoRefCount) return;
3131 /// When initializing a parameter, produce the value if it's marked
3132 /// __attribute__((ns_consumed)).
3133 if (Entity.isParameterKind()) {
3134 if (!Entity.isParameterConsumed())
3137 assert(Entity.getType()->isObjCRetainableType() &&
3138 "consuming an object of unretainable type?");
3139 Sequence.AddProduceObjCObjectStep(Entity.getType());
3141 /// When initializing a return value, if the return type is a
3142 /// retainable type, then returns need to immediately retain the
3143 /// object. If an autorelease is required, it will be done at the
3145 } else if (Entity.getKind() == InitializedEntity::EK_Result) {
3146 if (!Entity.getType()->isObjCRetainableType())
3149 Sequence.AddProduceObjCObjectStep(Entity.getType());
3153 static void TryListInitialization(Sema &S,
3154 const InitializedEntity &Entity,
3155 const InitializationKind &Kind,
3156 InitListExpr *InitList,
3157 InitializationSequence &Sequence);
3159 /// \brief When initializing from init list via constructor, handle
3160 /// initialization of an object of type std::initializer_list<T>.
3162 /// \return true if we have handled initialization of an object of type
3163 /// std::initializer_list<T>, false otherwise.
3164 static bool TryInitializerListConstruction(Sema &S,
3167 InitializationSequence &Sequence) {
3169 if (!S.isStdInitializerList(DestType, &E))
3172 if (S.RequireCompleteType(List->getExprLoc(), E, 0)) {
3173 Sequence.setIncompleteTypeFailure(E);
3177 // Try initializing a temporary array from the init list.
3178 QualType ArrayType = S.Context.getConstantArrayType(
3179 E.withConst(), llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
3180 List->getNumInits()),
3181 clang::ArrayType::Normal, 0);
3182 InitializedEntity HiddenArray =
3183 InitializedEntity::InitializeTemporary(ArrayType);
3184 InitializationKind Kind =
3185 InitializationKind::CreateDirectList(List->getExprLoc());
3186 TryListInitialization(S, HiddenArray, Kind, List, Sequence);
3188 Sequence.AddStdInitializerListConstructionStep(DestType);
3192 static OverloadingResult
3193 ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc,
3195 OverloadCandidateSet &CandidateSet,
3196 DeclContext::lookup_result Ctors,
3197 OverloadCandidateSet::iterator &Best,
3198 bool CopyInitializing, bool AllowExplicit,
3199 bool OnlyListConstructors, bool IsListInit) {
3200 CandidateSet.clear();
3202 for (NamedDecl *D : Ctors) {
3203 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess());
3204 bool SuppressUserConversions = false;
3206 // Find the constructor (which may be a template).
3207 CXXConstructorDecl *Constructor = nullptr;
3208 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D);
3209 if (ConstructorTmpl)
3210 Constructor = cast<CXXConstructorDecl>(
3211 ConstructorTmpl->getTemplatedDecl());
3213 Constructor = cast<CXXConstructorDecl>(D);
3215 // C++11 [over.best.ics]p4:
3216 // ... and the constructor or user-defined conversion function is a
3218 // - 13.3.1.3, when the argument is the temporary in the second step
3219 // of a class copy-initialization, or
3220 // - 13.3.1.4, 13.3.1.5, or 13.3.1.6 (in all cases),
3221 // user-defined conversion sequences are not considered.
3222 // FIXME: This breaks backward compatibility, e.g. PR12117. As a
3223 // temporary fix, let's re-instate the third bullet above until
3224 // there is a resolution in the standard, i.e.,
3225 // - 13.3.1.7 when the initializer list has exactly one element that is
3226 // itself an initializer list and a conversion to some class X or
3227 // reference to (possibly cv-qualified) X is considered for the first
3228 // parameter of a constructor of X.
3229 if ((CopyInitializing ||
3230 (IsListInit && Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&
3231 Constructor->isCopyOrMoveConstructor())
3232 SuppressUserConversions = true;
3235 if (!Constructor->isInvalidDecl() &&
3236 (AllowExplicit || !Constructor->isExplicit()) &&
3237 (!OnlyListConstructors || S.isInitListConstructor(Constructor))) {
3238 if (ConstructorTmpl)
3239 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl,
3240 /*ExplicitArgs*/ nullptr, Args,
3241 CandidateSet, SuppressUserConversions);
3243 // C++ [over.match.copy]p1:
3244 // - When initializing a temporary to be bound to the first parameter
3245 // of a constructor that takes a reference to possibly cv-qualified
3246 // T as its first argument, called with a single argument in the
3247 // context of direct-initialization, explicit conversion functions
3248 // are also considered.
3249 bool AllowExplicitConv = AllowExplicit && !CopyInitializing &&
3251 Constructor->isCopyOrMoveConstructor();
3252 S.AddOverloadCandidate(Constructor, FoundDecl, Args, CandidateSet,
3253 SuppressUserConversions,
3254 /*PartialOverloading=*/false,
3255 /*AllowExplicit=*/AllowExplicitConv);
3260 // Perform overload resolution and return the result.
3261 return CandidateSet.BestViableFunction(S, DeclLoc, Best);
3264 /// \brief Attempt initialization by constructor (C++ [dcl.init]), which
3265 /// enumerates the constructors of the initialized entity and performs overload
3266 /// resolution to select the best.
3267 /// \param IsListInit Is this list-initialization?
3268 /// \param IsInitListCopy Is this non-list-initialization resulting from a
3269 /// list-initialization from {x} where x is the same
3270 /// type as the entity?
3271 static void TryConstructorInitialization(Sema &S,
3272 const InitializedEntity &Entity,
3273 const InitializationKind &Kind,
3274 MultiExprArg Args, QualType DestType,
3275 InitializationSequence &Sequence,
3276 bool IsListInit = false,
3277 bool IsInitListCopy = false) {
3278 assert((!IsListInit || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&
3279 "IsListInit must come with a single initializer list argument.");
3281 // The type we're constructing needs to be complete.
3282 if (S.RequireCompleteType(Kind.getLocation(), DestType, 0)) {
3283 Sequence.setIncompleteTypeFailure(DestType);
3287 const RecordType *DestRecordType = DestType->getAs<RecordType>();
3288 assert(DestRecordType && "Constructor initialization requires record type");
3289 CXXRecordDecl *DestRecordDecl
3290 = cast<CXXRecordDecl>(DestRecordType->getDecl());
3292 // Build the candidate set directly in the initialization sequence
3293 // structure, so that it will persist if we fail.
3294 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
3296 // Determine whether we are allowed to call explicit constructors or
3297 // explicit conversion operators.
3298 bool AllowExplicit = Kind.AllowExplicit() || IsListInit;
3299 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy;
3301 // - Otherwise, if T is a class type, constructors are considered. The
3302 // applicable constructors are enumerated, and the best one is chosen
3303 // through overload resolution.
3304 DeclContext::lookup_result Ctors = S.LookupConstructors(DestRecordDecl);
3306 OverloadingResult Result = OR_No_Viable_Function;
3307 OverloadCandidateSet::iterator Best;
3308 bool AsInitializerList = false;
3310 // C++11 [over.match.list]p1, per DR1467:
3311 // When objects of non-aggregate type T are list-initialized, such that
3312 // 8.5.4 [dcl.init.list] specifies that overload resolution is performed
3313 // according to the rules in this section, overload resolution selects
3314 // the constructor in two phases:
3316 // - Initially, the candidate functions are the initializer-list
3317 // constructors of the class T and the argument list consists of the
3318 // initializer list as a single argument.
3320 InitListExpr *ILE = cast<InitListExpr>(Args[0]);
3321 AsInitializerList = true;
3323 // If the initializer list has no elements and T has a default constructor,
3324 // the first phase is omitted.
3325 if (ILE->getNumInits() != 0 || !DestRecordDecl->hasDefaultConstructor())
3326 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
3327 CandidateSet, Ctors, Best,
3328 CopyInitialization, AllowExplicit,
3329 /*OnlyListConstructor=*/true,
3332 // Time to unwrap the init list.
3333 Args = MultiExprArg(ILE->getInits(), ILE->getNumInits());
3336 // C++11 [over.match.list]p1:
3337 // - If no viable initializer-list constructor is found, overload resolution
3338 // is performed again, where the candidate functions are all the
3339 // constructors of the class T and the argument list consists of the
3340 // elements of the initializer list.
3341 if (Result == OR_No_Viable_Function) {
3342 AsInitializerList = false;
3343 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
3344 CandidateSet, Ctors, Best,
3345 CopyInitialization, AllowExplicit,
3346 /*OnlyListConstructors=*/false,
3350 Sequence.SetOverloadFailure(IsListInit ?
3351 InitializationSequence::FK_ListConstructorOverloadFailed :
3352 InitializationSequence::FK_ConstructorOverloadFailed,
3357 // C++11 [dcl.init]p6:
3358 // If a program calls for the default initialization of an object
3359 // of a const-qualified type T, T shall be a class type with a
3360 // user-provided default constructor.
3361 if (Kind.getKind() == InitializationKind::IK_Default &&
3362 Entity.getType().isConstQualified() &&
3363 !cast<CXXConstructorDecl>(Best->Function)->isUserProvided()) {
3364 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
3365 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
3369 // C++11 [over.match.list]p1:
3370 // In copy-list-initialization, if an explicit constructor is chosen, the
3371 // initializer is ill-formed.
3372 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
3373 if (IsListInit && !Kind.AllowExplicit() && CtorDecl->isExplicit()) {
3374 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor);
3378 // Add the constructor initialization step. Any cv-qualification conversion is
3379 // subsumed by the initialization.
3380 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3381 Sequence.AddConstructorInitializationStep(
3382 CtorDecl, Best->FoundDecl.getAccess(), DestType, HadMultipleCandidates,
3383 IsListInit | IsInitListCopy, AsInitializerList);
3387 ResolveOverloadedFunctionForReferenceBinding(Sema &S,
3389 QualType &SourceType,
3390 QualType &UnqualifiedSourceType,
3391 QualType UnqualifiedTargetType,
3392 InitializationSequence &Sequence) {
3393 if (S.Context.getCanonicalType(UnqualifiedSourceType) ==
3394 S.Context.OverloadTy) {
3395 DeclAccessPair Found;
3396 bool HadMultipleCandidates = false;
3397 if (FunctionDecl *Fn
3398 = S.ResolveAddressOfOverloadedFunction(Initializer,
3399 UnqualifiedTargetType,
3401 &HadMultipleCandidates)) {
3402 Sequence.AddAddressOverloadResolutionStep(Fn, Found,
3403 HadMultipleCandidates);
3404 SourceType = Fn->getType();
3405 UnqualifiedSourceType = SourceType.getUnqualifiedType();
3406 } else if (!UnqualifiedTargetType->isRecordType()) {
3407 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
3414 static void TryReferenceInitializationCore(Sema &S,
3415 const InitializedEntity &Entity,
3416 const InitializationKind &Kind,
3418 QualType cv1T1, QualType T1,
3420 QualType cv2T2, QualType T2,
3422 InitializationSequence &Sequence);
3424 static void TryValueInitialization(Sema &S,
3425 const InitializedEntity &Entity,
3426 const InitializationKind &Kind,
3427 InitializationSequence &Sequence,
3428 InitListExpr *InitList = nullptr);
3430 /// \brief Attempt list initialization of a reference.
3431 static void TryReferenceListInitialization(Sema &S,
3432 const InitializedEntity &Entity,
3433 const InitializationKind &Kind,
3434 InitListExpr *InitList,
3435 InitializationSequence &Sequence) {
3436 // First, catch C++03 where this isn't possible.
3437 if (!S.getLangOpts().CPlusPlus11) {
3438 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
3441 // Can't reference initialize a compound literal.
3442 if (Entity.getKind() == InitializedEntity::EK_CompoundLiteralInit) {
3443 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
3447 QualType DestType = Entity.getType();
3448 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
3450 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
3452 // Reference initialization via an initializer list works thus:
3453 // If the initializer list consists of a single element that is
3454 // reference-related to the referenced type, bind directly to that element
3455 // (possibly creating temporaries).
3456 // Otherwise, initialize a temporary with the initializer list and
3458 if (InitList->getNumInits() == 1) {
3459 Expr *Initializer = InitList->getInit(0);
3460 QualType cv2T2 = Initializer->getType();
3462 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
3464 // If this fails, creating a temporary wouldn't work either.
3465 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
3469 SourceLocation DeclLoc = Initializer->getLocStart();
3470 bool dummy1, dummy2, dummy3;
3471 Sema::ReferenceCompareResult RefRelationship
3472 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1,
3474 if (RefRelationship >= Sema::Ref_Related) {
3475 // Try to bind the reference here.
3476 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
3477 T1Quals, cv2T2, T2, T2Quals, Sequence);
3479 Sequence.RewrapReferenceInitList(cv1T1, InitList);
3483 // Update the initializer if we've resolved an overloaded function.
3484 if (Sequence.step_begin() != Sequence.step_end())
3485 Sequence.RewrapReferenceInitList(cv1T1, InitList);
3488 // Not reference-related. Create a temporary and bind to that.
3489 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
3491 TryListInitialization(S, TempEntity, Kind, InitList, Sequence);
3493 if (DestType->isRValueReferenceType() ||
3494 (T1Quals.hasConst() && !T1Quals.hasVolatile()))
3495 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
3498 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
3502 /// \brief Attempt list initialization (C++0x [dcl.init.list])
3503 static void TryListInitialization(Sema &S,
3504 const InitializedEntity &Entity,
3505 const InitializationKind &Kind,
3506 InitListExpr *InitList,
3507 InitializationSequence &Sequence) {
3508 QualType DestType = Entity.getType();
3510 // C++ doesn't allow scalar initialization with more than one argument.
3511 // But C99 complex numbers are scalars and it makes sense there.
3512 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() &&
3513 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) {
3514 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar);
3517 if (DestType->isReferenceType()) {
3518 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence);
3522 if (DestType->isRecordType() &&
3523 S.RequireCompleteType(InitList->getLocStart(), DestType, 0)) {
3524 Sequence.setIncompleteTypeFailure(DestType);
3528 // C++11 [dcl.init.list]p3, per DR1467:
3529 // - If T is a class type and the initializer list has a single element of
3530 // type cv U, where U is T or a class derived from T, the object is
3531 // initialized from that element (by copy-initialization for
3532 // copy-list-initialization, or by direct-initialization for
3533 // direct-list-initialization).
3534 // - Otherwise, if T is a character array and the initializer list has a
3535 // single element that is an appropriately-typed string literal
3536 // (8.5.2 [dcl.init.string]), initialization is performed as described
3538 // - Otherwise, if T is an aggregate, [...] (continue below).
3539 if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1) {
3540 if (DestType->isRecordType()) {
3541 QualType InitType = InitList->getInit(0)->getType();
3542 if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
3543 S.IsDerivedFrom(InitType, DestType)) {
3544 Expr *InitAsExpr = InitList->getInit(0);
3545 TryConstructorInitialization(S, Entity, Kind, InitAsExpr, DestType,
3546 Sequence, /*InitListSyntax*/ false,
3547 /*IsInitListCopy*/ true);
3551 if (const ArrayType *DestAT = S.Context.getAsArrayType(DestType)) {
3552 Expr *SubInit[1] = {InitList->getInit(0)};
3553 if (!isa<VariableArrayType>(DestAT) &&
3554 IsStringInit(SubInit[0], DestAT, S.Context) == SIF_None) {
3555 InitializationKind SubKind =
3556 Kind.getKind() == InitializationKind::IK_DirectList
3557 ? InitializationKind::CreateDirect(Kind.getLocation(),
3558 InitList->getLBraceLoc(),
3559 InitList->getRBraceLoc())
3561 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
3562 /*TopLevelOfInitList*/ true);
3564 // TryStringLiteralInitialization() (in InitializeFrom()) will fail if
3565 // the element is not an appropriately-typed string literal, in which
3566 // case we should proceed as in C++11 (below).
3568 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
3575 // C++11 [dcl.init.list]p3:
3576 // - If T is an aggregate, aggregate initialization is performed.
3577 if (DestType->isRecordType() && !DestType->isAggregateType()) {
3578 if (S.getLangOpts().CPlusPlus11) {
3579 // - Otherwise, if the initializer list has no elements and T is a
3580 // class type with a default constructor, the object is
3581 // value-initialized.
3582 if (InitList->getNumInits() == 0) {
3583 CXXRecordDecl *RD = DestType->getAsCXXRecordDecl();
3584 if (RD->hasDefaultConstructor()) {
3585 TryValueInitialization(S, Entity, Kind, Sequence, InitList);
3590 // - Otherwise, if T is a specialization of std::initializer_list<E>,
3591 // an initializer_list object constructed [...]
3592 if (TryInitializerListConstruction(S, InitList, DestType, Sequence))
3595 // - Otherwise, if T is a class type, constructors are considered.
3596 Expr *InitListAsExpr = InitList;
3597 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
3598 Sequence, /*InitListSyntax*/ true);
3600 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType);
3604 if (S.getLangOpts().CPlusPlus && !DestType->isAggregateType() &&
3605 InitList->getNumInits() == 1 &&
3606 InitList->getInit(0)->getType()->isRecordType()) {
3607 // - Otherwise, if the initializer list has a single element of type E
3608 // [...references are handled above...], the object or reference is
3609 // initialized from that element (by copy-initialization for
3610 // copy-list-initialization, or by direct-initialization for
3611 // direct-list-initialization); if a narrowing conversion is required
3612 // to convert the element to T, the program is ill-formed.
3614 // Per core-24034, this is direct-initialization if we were performing
3615 // direct-list-initialization and copy-initialization otherwise.
3616 // We can't use InitListChecker for this, because it always performs
3617 // copy-initialization. This only matters if we might use an 'explicit'
3618 // conversion operator, so we only need to handle the cases where the source
3619 // is of record type.
3620 InitializationKind SubKind =
3621 Kind.getKind() == InitializationKind::IK_DirectList
3622 ? InitializationKind::CreateDirect(Kind.getLocation(),
3623 InitList->getLBraceLoc(),
3624 InitList->getRBraceLoc())
3626 Expr *SubInit[1] = { InitList->getInit(0) };
3627 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
3628 /*TopLevelOfInitList*/true);
3630 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
3634 InitListChecker CheckInitList(S, Entity, InitList,
3635 DestType, /*VerifyOnly=*/true);
3636 if (CheckInitList.HadError()) {
3637 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed);
3641 // Add the list initialization step with the built init list.
3642 Sequence.AddListInitializationStep(DestType);
3645 /// \brief Try a reference initialization that involves calling a conversion
3647 static OverloadingResult TryRefInitWithConversionFunction(Sema &S,
3648 const InitializedEntity &Entity,
3649 const InitializationKind &Kind,
3652 InitializationSequence &Sequence) {
3653 QualType DestType = Entity.getType();
3654 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
3655 QualType T1 = cv1T1.getUnqualifiedType();
3656 QualType cv2T2 = Initializer->getType();
3657 QualType T2 = cv2T2.getUnqualifiedType();
3660 bool ObjCConversion;
3661 bool ObjCLifetimeConversion;
3662 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(),
3663 T1, T2, DerivedToBase,
3665 ObjCLifetimeConversion) &&
3666 "Must have incompatible references when binding via conversion");
3667 (void)DerivedToBase;
3668 (void)ObjCConversion;
3669 (void)ObjCLifetimeConversion;
3671 // Build the candidate set directly in the initialization sequence
3672 // structure, so that it will persist if we fail.
3673 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
3674 CandidateSet.clear();
3676 // Determine whether we are allowed to call explicit constructors or
3677 // explicit conversion operators.
3678 bool AllowExplicit = Kind.AllowExplicit();
3679 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctionsInRefBinding();
3681 const RecordType *T1RecordType = nullptr;
3682 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) &&
3683 !S.RequireCompleteType(Kind.getLocation(), T1, 0)) {
3684 // The type we're converting to is a class type. Enumerate its constructors
3685 // to see if there is a suitable conversion.
3686 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl());
3688 for (NamedDecl *D : S.LookupConstructors(T1RecordDecl)) {
3689 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess());
3691 // Find the constructor (which may be a template).
3692 CXXConstructorDecl *Constructor = nullptr;
3693 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D);
3694 if (ConstructorTmpl)
3695 Constructor = cast<CXXConstructorDecl>(
3696 ConstructorTmpl->getTemplatedDecl());
3698 Constructor = cast<CXXConstructorDecl>(D);
3700 if (!Constructor->isInvalidDecl() &&
3701 Constructor->isConvertingConstructor(AllowExplicit)) {
3702 if (ConstructorTmpl)
3703 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl,
3704 /*ExplicitArgs*/ nullptr,
3705 Initializer, CandidateSet,
3706 /*SuppressUserConversions=*/true);
3708 S.AddOverloadCandidate(Constructor, FoundDecl,
3709 Initializer, CandidateSet,
3710 /*SuppressUserConversions=*/true);
3714 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl())
3715 return OR_No_Viable_Function;
3717 const RecordType *T2RecordType = nullptr;
3718 if ((T2RecordType = T2->getAs<RecordType>()) &&
3719 !S.RequireCompleteType(Kind.getLocation(), T2, 0)) {
3720 // The type we're converting from is a class type, enumerate its conversion
3722 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
3724 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
3725 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
3727 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
3728 if (isa<UsingShadowDecl>(D))
3729 D = cast<UsingShadowDecl>(D)->getTargetDecl();
3731 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
3732 CXXConversionDecl *Conv;
3734 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
3736 Conv = cast<CXXConversionDecl>(D);
3738 // If the conversion function doesn't return a reference type,
3739 // it can't be considered for this conversion unless we're allowed to
3740 // consider rvalues.
3741 // FIXME: Do we need to make sure that we only consider conversion
3742 // candidates with reference-compatible results? That might be needed to
3744 if ((AllowExplicitConvs || !Conv->isExplicit()) &&
3745 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){
3747 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(),
3748 ActingDC, Initializer,
3749 DestType, CandidateSet,
3750 /*AllowObjCConversionOnExplicit=*/
3753 S.AddConversionCandidate(Conv, I.getPair(), ActingDC,
3754 Initializer, DestType, CandidateSet,
3755 /*AllowObjCConversionOnExplicit=*/false);
3759 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl())
3760 return OR_No_Viable_Function;
3762 SourceLocation DeclLoc = Initializer->getLocStart();
3764 // Perform overload resolution. If it fails, return the failed result.
3765 OverloadCandidateSet::iterator Best;
3766 if (OverloadingResult Result
3767 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true))
3770 FunctionDecl *Function = Best->Function;
3771 // This is the overload that will be used for this initialization step if we
3772 // use this initialization. Mark it as referenced.
3773 Function->setReferenced();
3775 // Compute the returned type of the conversion.
3776 if (isa<CXXConversionDecl>(Function))
3777 T2 = Function->getReturnType();
3781 // Add the user-defined conversion step.
3782 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3783 Sequence.AddUserConversionStep(Function, Best->FoundDecl,
3784 T2.getNonLValueExprType(S.Context),
3785 HadMultipleCandidates);
3787 // Determine whether we need to perform derived-to-base or
3788 // cv-qualification adjustments.
3789 ExprValueKind VK = VK_RValue;
3790 if (T2->isLValueReferenceType())
3792 else if (const RValueReferenceType *RRef = T2->getAs<RValueReferenceType>())
3793 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue;
3795 bool NewDerivedToBase = false;
3796 bool NewObjCConversion = false;
3797 bool NewObjCLifetimeConversion = false;
3798 Sema::ReferenceCompareResult NewRefRelationship
3799 = S.CompareReferenceRelationship(DeclLoc, T1,
3800 T2.getNonLValueExprType(S.Context),
3801 NewDerivedToBase, NewObjCConversion,
3802 NewObjCLifetimeConversion);
3803 if (NewRefRelationship == Sema::Ref_Incompatible) {
3804 // If the type we've converted to is not reference-related to the
3805 // type we're looking for, then there is another conversion step
3806 // we need to perform to produce a temporary of the right type
3807 // that we'll be binding to.
3808 ImplicitConversionSequence ICS;
3810 ICS.Standard = Best->FinalConversion;
3811 T2 = ICS.Standard.getToType(2);
3812 Sequence.AddConversionSequenceStep(ICS, T2);
3813 } else if (NewDerivedToBase)
3814 Sequence.AddDerivedToBaseCastStep(
3815 S.Context.getQualifiedType(T1,
3816 T2.getNonReferenceType().getQualifiers()),
3818 else if (NewObjCConversion)
3819 Sequence.AddObjCObjectConversionStep(
3820 S.Context.getQualifiedType(T1,
3821 T2.getNonReferenceType().getQualifiers()));
3823 if (cv1T1.getQualifiers() != T2.getNonReferenceType().getQualifiers())
3824 Sequence.AddQualificationConversionStep(cv1T1, VK);
3826 Sequence.AddReferenceBindingStep(cv1T1, !T2->isReferenceType());
3830 static void CheckCXX98CompatAccessibleCopy(Sema &S,
3831 const InitializedEntity &Entity,
3834 /// \brief Attempt reference initialization (C++0x [dcl.init.ref])
3835 static void TryReferenceInitialization(Sema &S,
3836 const InitializedEntity &Entity,
3837 const InitializationKind &Kind,
3839 InitializationSequence &Sequence) {
3840 QualType DestType = Entity.getType();
3841 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
3843 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
3844 QualType cv2T2 = Initializer->getType();
3846 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
3848 // If the initializer is the address of an overloaded function, try
3849 // to resolve the overloaded function. If all goes well, T2 is the
3850 // type of the resulting function.
3851 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
3855 // Delegate everything else to a subfunction.
3856 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
3857 T1Quals, cv2T2, T2, T2Quals, Sequence);
3860 /// Converts the target of reference initialization so that it has the
3861 /// appropriate qualifiers and value kind.
3863 /// In this case, 'x' is an 'int' lvalue, but it needs to be 'const int'.
3866 /// const int &r = x;
3869 /// In this case the reference is binding to a bitfield lvalue, which isn't
3870 /// valid. Perform a load to create a lifetime-extended temporary instead.
3872 /// const int &r = someStruct.bitfield;
3874 static ExprValueKind
3875 convertQualifiersAndValueKindIfNecessary(Sema &S,
3876 InitializationSequence &Sequence,
3882 bool IsNonAddressableType = Initializer->refersToBitField() ||
3883 Initializer->refersToVectorElement();
3885 if (IsNonAddressableType) {
3886 // C++11 [dcl.init.ref]p5: [...] Otherwise, the reference shall be an
3887 // lvalue reference to a non-volatile const type, or the reference shall be
3888 // an rvalue reference.
3890 // If not, we can't make a temporary and bind to that. Give up and allow the
3891 // error to be diagnosed later.
3892 if (IsLValueRef && (!T1Quals.hasConst() || T1Quals.hasVolatile())) {
3893 assert(Initializer->isGLValue());
3894 return Initializer->getValueKind();
3897 // Force a load so we can materialize a temporary.
3898 Sequence.AddLValueToRValueStep(cv1T1.getUnqualifiedType());
3902 if (T1Quals != T2Quals) {
3903 Sequence.AddQualificationConversionStep(cv1T1,
3904 Initializer->getValueKind());
3907 return Initializer->getValueKind();
3911 /// \brief Reference initialization without resolving overloaded functions.
3912 static void TryReferenceInitializationCore(Sema &S,
3913 const InitializedEntity &Entity,
3914 const InitializationKind &Kind,
3916 QualType cv1T1, QualType T1,
3918 QualType cv2T2, QualType T2,
3920 InitializationSequence &Sequence) {
3921 QualType DestType = Entity.getType();
3922 SourceLocation DeclLoc = Initializer->getLocStart();
3923 // Compute some basic properties of the types and the initializer.
3924 bool isLValueRef = DestType->isLValueReferenceType();
3925 bool isRValueRef = !isLValueRef;
3926 bool DerivedToBase = false;
3927 bool ObjCConversion = false;
3928 bool ObjCLifetimeConversion = false;
3929 Expr::Classification InitCategory = Initializer->Classify(S.Context);
3930 Sema::ReferenceCompareResult RefRelationship
3931 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase,
3932 ObjCConversion, ObjCLifetimeConversion);
3934 // C++0x [dcl.init.ref]p5:
3935 // A reference to type "cv1 T1" is initialized by an expression of type
3936 // "cv2 T2" as follows:
3938 // - If the reference is an lvalue reference and the initializer
3940 // Note the analogous bullet points for rvalue refs to functions. Because
3941 // there are no function rvalues in C++, rvalue refs to functions are treated
3942 // like lvalue refs.
3943 OverloadingResult ConvOvlResult = OR_Success;
3944 bool T1Function = T1->isFunctionType();
3945 if (isLValueRef || T1Function) {
3946 if (InitCategory.isLValue() &&
3947 (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification ||
3948 (Kind.isCStyleOrFunctionalCast() &&
3949 RefRelationship == Sema::Ref_Related))) {
3950 // - is an lvalue (but is not a bit-field), and "cv1 T1" is
3951 // reference-compatible with "cv2 T2," or
3953 // Per C++ [over.best.ics]p2, we don't diagnose whether the lvalue is a
3954 // bit-field when we're determining whether the reference initialization
3955 // can occur. However, we do pay attention to whether it is a bit-field
3956 // to decide whether we're actually binding to a temporary created from
3959 Sequence.AddDerivedToBaseCastStep(
3960 S.Context.getQualifiedType(T1, T2Quals),
3962 else if (ObjCConversion)
3963 Sequence.AddObjCObjectConversionStep(
3964 S.Context.getQualifiedType(T1, T2Quals));
3966 ExprValueKind ValueKind =
3967 convertQualifiersAndValueKindIfNecessary(S, Sequence, Initializer,
3968 cv1T1, T1Quals, T2Quals,
3970 Sequence.AddReferenceBindingStep(cv1T1, ValueKind == VK_RValue);
3974 // - has a class type (i.e., T2 is a class type), where T1 is not
3975 // reference-related to T2, and can be implicitly converted to an
3976 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible
3977 // with "cv3 T3" (this conversion is selected by enumerating the
3978 // applicable conversion functions (13.3.1.6) and choosing the best
3979 // one through overload resolution (13.3)),
3980 // If we have an rvalue ref to function type here, the rhs must be
3981 // an rvalue. DR1287 removed the "implicitly" here.
3982 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() &&
3983 (isLValueRef || InitCategory.isRValue())) {
3984 ConvOvlResult = TryRefInitWithConversionFunction(
3985 S, Entity, Kind, Initializer, /*AllowRValues*/isRValueRef, Sequence);
3986 if (ConvOvlResult == OR_Success)
3988 if (ConvOvlResult != OR_No_Viable_Function)
3989 Sequence.SetOverloadFailure(
3990 InitializationSequence::FK_ReferenceInitOverloadFailed,
3995 // - Otherwise, the reference shall be an lvalue reference to a
3996 // non-volatile const type (i.e., cv1 shall be const), or the reference
3997 // shall be an rvalue reference.
3998 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile())) {
3999 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4000 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4001 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4002 Sequence.SetOverloadFailure(
4003 InitializationSequence::FK_ReferenceInitOverloadFailed,
4006 Sequence.SetFailed(InitCategory.isLValue()
4007 ? (RefRelationship == Sema::Ref_Related
4008 ? InitializationSequence::FK_ReferenceInitDropsQualifiers
4009 : InitializationSequence::FK_NonConstLValueReferenceBindingToUnrelated)
4010 : InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
4015 // - If the initializer expression
4016 // - is an xvalue, class prvalue, array prvalue, or function lvalue and
4017 // "cv1 T1" is reference-compatible with "cv2 T2"
4018 // Note: functions are handled below.
4020 (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification ||
4021 (Kind.isCStyleOrFunctionalCast() &&
4022 RefRelationship == Sema::Ref_Related)) &&
4023 (InitCategory.isXValue() ||
4024 (InitCategory.isPRValue() && T2->isRecordType()) ||
4025 (InitCategory.isPRValue() && T2->isArrayType()))) {
4026 ExprValueKind ValueKind = InitCategory.isXValue()? VK_XValue : VK_RValue;
4027 if (InitCategory.isPRValue() && T2->isRecordType()) {
4028 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the
4029 // compiler the freedom to perform a copy here or bind to the
4030 // object, while C++0x requires that we bind directly to the
4031 // object. Hence, we always bind to the object without making an
4032 // extra copy. However, in C++03 requires that we check for the
4033 // presence of a suitable copy constructor:
4035 // The constructor that would be used to make the copy shall
4036 // be callable whether or not the copy is actually done.
4037 if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt)
4038 Sequence.AddExtraneousCopyToTemporary(cv2T2);
4039 else if (S.getLangOpts().CPlusPlus11)
4040 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer);
4044 Sequence.AddDerivedToBaseCastStep(S.Context.getQualifiedType(T1, T2Quals),
4046 else if (ObjCConversion)
4047 Sequence.AddObjCObjectConversionStep(
4048 S.Context.getQualifiedType(T1, T2Quals));
4050 ValueKind = convertQualifiersAndValueKindIfNecessary(S, Sequence,
4055 Sequence.AddReferenceBindingStep(cv1T1, ValueKind == VK_RValue);
4059 // - has a class type (i.e., T2 is a class type), where T1 is not
4060 // reference-related to T2, and can be implicitly converted to an
4061 // xvalue, class prvalue, or function lvalue of type "cv3 T3",
4062 // where "cv1 T1" is reference-compatible with "cv3 T3",
4064 // DR1287 removes the "implicitly" here.
4065 if (T2->isRecordType()) {
4066 if (RefRelationship == Sema::Ref_Incompatible) {
4067 ConvOvlResult = TryRefInitWithConversionFunction(
4068 S, Entity, Kind, Initializer, /*AllowRValues*/true, Sequence);
4070 Sequence.SetOverloadFailure(
4071 InitializationSequence::FK_ReferenceInitOverloadFailed,
4077 if ((RefRelationship == Sema::Ref_Compatible ||
4078 RefRelationship == Sema::Ref_Compatible_With_Added_Qualification) &&
4079 isRValueRef && InitCategory.isLValue()) {
4081 InitializationSequence::FK_RValueReferenceBindingToLValue);
4085 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
4089 // - Otherwise, a temporary of type "cv1 T1" is created and initialized
4090 // from the initializer expression using the rules for a non-reference
4091 // copy-initialization (8.5). The reference is then bound to the
4094 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
4096 // FIXME: Why do we use an implicit conversion here rather than trying
4097 // copy-initialization?
4098 ImplicitConversionSequence ICS
4099 = S.TryImplicitConversion(Initializer, TempEntity.getType(),
4100 /*SuppressUserConversions=*/false,
4101 /*AllowExplicit=*/false,
4102 /*FIXME:InOverloadResolution=*/false,
4103 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
4104 /*AllowObjCWritebackConversion=*/false);
4107 // FIXME: Use the conversion function set stored in ICS to turn
4108 // this into an overloading ambiguity diagnostic. However, we need
4109 // to keep that set as an OverloadCandidateSet rather than as some
4110 // other kind of set.
4111 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4112 Sequence.SetOverloadFailure(
4113 InitializationSequence::FK_ReferenceInitOverloadFailed,
4115 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4116 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4118 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed);
4121 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType());
4124 // [...] If T1 is reference-related to T2, cv1 must be the
4125 // same cv-qualification as, or greater cv-qualification
4126 // than, cv2; otherwise, the program is ill-formed.
4127 unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
4128 unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
4129 if (RefRelationship == Sema::Ref_Related &&
4130 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) {
4131 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
4135 // [...] If T1 is reference-related to T2 and the reference is an rvalue
4136 // reference, the initializer expression shall not be an lvalue.
4137 if (RefRelationship >= Sema::Ref_Related && !isLValueRef &&
4138 InitCategory.isLValue()) {
4140 InitializationSequence::FK_RValueReferenceBindingToLValue);
4144 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
4148 /// \brief Attempt character array initialization from a string literal
4149 /// (C++ [dcl.init.string], C99 6.7.8).
4150 static void TryStringLiteralInitialization(Sema &S,
4151 const InitializedEntity &Entity,
4152 const InitializationKind &Kind,
4154 InitializationSequence &Sequence) {
4155 Sequence.AddStringInitStep(Entity.getType());
4158 /// \brief Attempt value initialization (C++ [dcl.init]p7).
4159 static void TryValueInitialization(Sema &S,
4160 const InitializedEntity &Entity,
4161 const InitializationKind &Kind,
4162 InitializationSequence &Sequence,
4163 InitListExpr *InitList) {
4164 assert((!InitList || InitList->getNumInits() == 0) &&
4165 "Shouldn't use value-init for non-empty init lists");
4167 // C++98 [dcl.init]p5, C++11 [dcl.init]p7:
4169 // To value-initialize an object of type T means:
4170 QualType T = Entity.getType();
4172 // -- if T is an array type, then each element is value-initialized;
4173 T = S.Context.getBaseElementType(T);
4175 if (const RecordType *RT = T->getAs<RecordType>()) {
4176 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
4177 bool NeedZeroInitialization = true;
4178 if (!S.getLangOpts().CPlusPlus11) {
4180 // -- if T is a class type (clause 9) with a user-declared constructor
4181 // (12.1), then the default constructor for T is called (and the
4182 // initialization is ill-formed if T has no accessible default
4184 if (ClassDecl->hasUserDeclaredConstructor())
4185 NeedZeroInitialization = false;
4188 // -- if T is a class type (clause 9) with either no default constructor
4189 // (12.1 [class.ctor]) or a default constructor that is user-provided
4190 // or deleted, then the object is default-initialized;
4191 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl);
4192 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted())
4193 NeedZeroInitialization = false;
4196 // -- if T is a (possibly cv-qualified) non-union class type without a
4197 // user-provided or deleted default constructor, then the object is
4198 // zero-initialized and, if T has a non-trivial default constructor,
4199 // default-initialized;
4200 // The 'non-union' here was removed by DR1502. The 'non-trivial default
4201 // constructor' part was removed by DR1507.
4202 if (NeedZeroInitialization)
4203 Sequence.AddZeroInitializationStep(Entity.getType());
4206 // -- if T is a non-union class type without a user-declared constructor,
4207 // then every non-static data member and base class component of T is
4208 // value-initialized;
4209 // [...] A program that calls for [...] value-initialization of an
4210 // entity of reference type is ill-formed.
4212 // C++11 doesn't need this handling, because value-initialization does not
4213 // occur recursively there, and the implicit default constructor is
4214 // defined as deleted in the problematic cases.
4215 if (!S.getLangOpts().CPlusPlus11 &&
4216 ClassDecl->hasUninitializedReferenceMember()) {
4217 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference);
4221 // If this is list-value-initialization, pass the empty init list on when
4222 // building the constructor call. This affects the semantics of a few
4223 // things (such as whether an explicit default constructor can be called).
4224 Expr *InitListAsExpr = InitList;
4225 MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0);
4226 bool InitListSyntax = InitList;
4228 return TryConstructorInitialization(S, Entity, Kind, Args, T, Sequence,
4233 Sequence.AddZeroInitializationStep(Entity.getType());
4236 /// \brief Attempt default initialization (C++ [dcl.init]p6).
4237 static void TryDefaultInitialization(Sema &S,
4238 const InitializedEntity &Entity,
4239 const InitializationKind &Kind,
4240 InitializationSequence &Sequence) {
4241 assert(Kind.getKind() == InitializationKind::IK_Default);
4243 // C++ [dcl.init]p6:
4244 // To default-initialize an object of type T means:
4245 // - if T is an array type, each element is default-initialized;
4246 QualType DestType = S.Context.getBaseElementType(Entity.getType());
4248 // - if T is a (possibly cv-qualified) class type (Clause 9), the default
4249 // constructor for T is called (and the initialization is ill-formed if
4250 // T has no accessible default constructor);
4251 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) {
4252 TryConstructorInitialization(S, Entity, Kind, None, DestType, Sequence);
4256 // - otherwise, no initialization is performed.
4258 // If a program calls for the default initialization of an object of
4259 // a const-qualified type T, T shall be a class type with a user-provided
4260 // default constructor.
4261 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) {
4262 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
4263 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
4267 // If the destination type has a lifetime property, zero-initialize it.
4268 if (DestType.getQualifiers().hasObjCLifetime()) {
4269 Sequence.AddZeroInitializationStep(Entity.getType());
4274 /// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]),
4275 /// which enumerates all conversion functions and performs overload resolution
4276 /// to select the best.
4277 static void TryUserDefinedConversion(Sema &S,
4279 const InitializationKind &Kind,
4281 InitializationSequence &Sequence,
4282 bool TopLevelOfInitList) {
4283 assert(!DestType->isReferenceType() && "References are handled elsewhere");
4284 QualType SourceType = Initializer->getType();
4285 assert((DestType->isRecordType() || SourceType->isRecordType()) &&
4286 "Must have a class type to perform a user-defined conversion");
4288 // Build the candidate set directly in the initialization sequence
4289 // structure, so that it will persist if we fail.
4290 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4291 CandidateSet.clear();
4293 // Determine whether we are allowed to call explicit constructors or
4294 // explicit conversion operators.
4295 bool AllowExplicit = Kind.AllowExplicit();
4297 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) {
4298 // The type we're converting to is a class type. Enumerate its constructors
4299 // to see if there is a suitable conversion.
4300 CXXRecordDecl *DestRecordDecl
4301 = cast<CXXRecordDecl>(DestRecordType->getDecl());
4303 // Try to complete the type we're converting to.
4304 if (!S.RequireCompleteType(Kind.getLocation(), DestType, 0)) {
4305 DeclContext::lookup_result R = S.LookupConstructors(DestRecordDecl);
4306 // The container holding the constructors can under certain conditions
4307 // be changed while iterating. To be safe we copy the lookup results
4308 // to a new container.
4309 SmallVector<NamedDecl*, 8> CopyOfCon(R.begin(), R.end());
4310 for (SmallVectorImpl<NamedDecl *>::iterator
4311 Con = CopyOfCon.begin(), ConEnd = CopyOfCon.end();
4312 Con != ConEnd; ++Con) {
4313 NamedDecl *D = *Con;
4314 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess());
4316 // Find the constructor (which may be a template).
4317 CXXConstructorDecl *Constructor = nullptr;
4318 FunctionTemplateDecl *ConstructorTmpl
4319 = dyn_cast<FunctionTemplateDecl>(D);
4320 if (ConstructorTmpl)
4321 Constructor = cast<CXXConstructorDecl>(
4322 ConstructorTmpl->getTemplatedDecl());
4324 Constructor = cast<CXXConstructorDecl>(D);
4326 if (!Constructor->isInvalidDecl() &&
4327 Constructor->isConvertingConstructor(AllowExplicit)) {
4328 if (ConstructorTmpl)
4329 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl,
4330 /*ExplicitArgs*/ nullptr,
4331 Initializer, CandidateSet,
4332 /*SuppressUserConversions=*/true);
4334 S.AddOverloadCandidate(Constructor, FoundDecl,
4335 Initializer, CandidateSet,
4336 /*SuppressUserConversions=*/true);
4342 SourceLocation DeclLoc = Initializer->getLocStart();
4344 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) {
4345 // The type we're converting from is a class type, enumerate its conversion
4348 // We can only enumerate the conversion functions for a complete type; if
4349 // the type isn't complete, simply skip this step.
4350 if (!S.RequireCompleteType(DeclLoc, SourceType, 0)) {
4351 CXXRecordDecl *SourceRecordDecl
4352 = cast<CXXRecordDecl>(SourceRecordType->getDecl());
4354 const auto &Conversions =
4355 SourceRecordDecl->getVisibleConversionFunctions();
4356 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4358 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4359 if (isa<UsingShadowDecl>(D))
4360 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4362 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4363 CXXConversionDecl *Conv;
4365 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4367 Conv = cast<CXXConversionDecl>(D);
4369 if (AllowExplicit || !Conv->isExplicit()) {
4371 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(),
4372 ActingDC, Initializer, DestType,
4373 CandidateSet, AllowExplicit);
4375 S.AddConversionCandidate(Conv, I.getPair(), ActingDC,
4376 Initializer, DestType, CandidateSet,
4383 // Perform overload resolution. If it fails, return the failed result.
4384 OverloadCandidateSet::iterator Best;
4385 if (OverloadingResult Result
4386 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) {
4387 Sequence.SetOverloadFailure(
4388 InitializationSequence::FK_UserConversionOverloadFailed,
4393 FunctionDecl *Function = Best->Function;
4394 Function->setReferenced();
4395 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4397 if (isa<CXXConstructorDecl>(Function)) {
4398 // Add the user-defined conversion step. Any cv-qualification conversion is
4399 // subsumed by the initialization. Per DR5, the created temporary is of the
4400 // cv-unqualified type of the destination.
4401 Sequence.AddUserConversionStep(Function, Best->FoundDecl,
4402 DestType.getUnqualifiedType(),
4403 HadMultipleCandidates);
4407 // Add the user-defined conversion step that calls the conversion function.
4408 QualType ConvType = Function->getCallResultType();
4409 if (ConvType->getAs<RecordType>()) {
4410 // If we're converting to a class type, there may be an copy of
4411 // the resulting temporary object (possible to create an object of
4412 // a base class type). That copy is not a separate conversion, so
4413 // we just make a note of the actual destination type (possibly a
4414 // base class of the type returned by the conversion function) and
4415 // let the user-defined conversion step handle the conversion.
4416 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType,
4417 HadMultipleCandidates);
4421 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType,
4422 HadMultipleCandidates);
4424 // If the conversion following the call to the conversion function
4425 // is interesting, add it as a separate step.
4426 if (Best->FinalConversion.First || Best->FinalConversion.Second ||
4427 Best->FinalConversion.Third) {
4428 ImplicitConversionSequence ICS;
4430 ICS.Standard = Best->FinalConversion;
4431 Sequence.AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
4435 /// An egregious hack for compatibility with libstdc++-4.2: in <tr1/hashtable>,
4436 /// a function with a pointer return type contains a 'return false;' statement.
4437 /// In C++11, 'false' is not a null pointer, so this breaks the build of any
4438 /// code using that header.
4440 /// Work around this by treating 'return false;' as zero-initializing the result
4441 /// if it's used in a pointer-returning function in a system header.
4442 static bool isLibstdcxxPointerReturnFalseHack(Sema &S,
4443 const InitializedEntity &Entity,
4445 return S.getLangOpts().CPlusPlus11 &&
4446 Entity.getKind() == InitializedEntity::EK_Result &&
4447 Entity.getType()->isPointerType() &&
4448 isa<CXXBoolLiteralExpr>(Init) &&
4449 !cast<CXXBoolLiteralExpr>(Init)->getValue() &&
4450 S.getSourceManager().isInSystemHeader(Init->getExprLoc());
4453 /// The non-zero enum values here are indexes into diagnostic alternatives.
4454 enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar };
4456 /// Determines whether this expression is an acceptable ICR source.
4457 static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e,
4458 bool isAddressOf, bool &isWeakAccess) {
4460 e = e->IgnoreParens();
4462 // Skip address-of nodes.
4463 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
4464 if (op->getOpcode() == UO_AddrOf)
4465 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true,
4468 // Skip certain casts.
4469 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) {
4470 switch (ce->getCastKind()) {
4473 case CK_LValueBitCast:
4475 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess);
4477 case CK_ArrayToPointerDecay:
4478 return IIK_nonscalar;
4480 case CK_NullToPointer:
4487 // If we have a declaration reference, it had better be a local variable.
4488 } else if (isa<DeclRefExpr>(e)) {
4489 // set isWeakAccess to true, to mean that there will be an implicit
4490 // load which requires a cleanup.
4491 if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
4492 isWeakAccess = true;
4494 if (!isAddressOf) return IIK_nonlocal;
4496 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl());
4497 if (!var) return IIK_nonlocal;
4499 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal);
4501 // If we have a conditional operator, check both sides.
4502 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) {
4503 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf,
4507 return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess);
4509 // These are never scalar.
4510 } else if (isa<ArraySubscriptExpr>(e)) {
4511 return IIK_nonscalar;
4513 // Otherwise, it needs to be a null pointer constant.
4515 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull)
4516 ? IIK_okay : IIK_nonlocal);
4519 return IIK_nonlocal;
4522 /// Check whether the given expression is a valid operand for an
4523 /// indirect copy/restore.
4524 static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) {
4525 assert(src->isRValue());
4526 bool isWeakAccess = false;
4527 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess);
4528 // If isWeakAccess to true, there will be an implicit
4529 // load which requires a cleanup.
4530 if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess)
4531 S.ExprNeedsCleanups = true;
4533 if (iik == IIK_okay) return;
4535 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback)
4536 << ((unsigned) iik - 1) // shift index into diagnostic explanations
4537 << src->getSourceRange();
4540 /// \brief Determine whether we have compatible array types for the
4541 /// purposes of GNU by-copy array initialization.
4542 static bool hasCompatibleArrayTypes(ASTContext &Context, const ArrayType *Dest,
4543 const ArrayType *Source) {
4544 // If the source and destination array types are equivalent, we're
4546 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0)))
4549 // Make sure that the element types are the same.
4550 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType()))
4553 // The only mismatch we allow is when the destination is an
4554 // incomplete array type and the source is a constant array type.
4555 return Source->isConstantArrayType() && Dest->isIncompleteArrayType();
4558 static bool tryObjCWritebackConversion(Sema &S,
4559 InitializationSequence &Sequence,
4560 const InitializedEntity &Entity,
4561 Expr *Initializer) {
4562 bool ArrayDecay = false;
4563 QualType ArgType = Initializer->getType();
4564 QualType ArgPointee;
4565 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) {
4567 ArgPointee = ArgArrayType->getElementType();
4568 ArgType = S.Context.getPointerType(ArgPointee);
4571 // Handle write-back conversion.
4572 QualType ConvertedArgType;
4573 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(),
4577 // We should copy unless we're passing to an argument explicitly
4579 bool ShouldCopy = true;
4580 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
4581 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
4583 // Do we need an lvalue conversion?
4584 if (ArrayDecay || Initializer->isGLValue()) {
4585 ImplicitConversionSequence ICS;
4587 ICS.Standard.setAsIdentityConversion();
4589 QualType ResultType;
4591 ICS.Standard.First = ICK_Array_To_Pointer;
4592 ResultType = S.Context.getPointerType(ArgPointee);
4594 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
4595 ResultType = Initializer->getType().getNonLValueExprType(S.Context);
4598 Sequence.AddConversionSequenceStep(ICS, ResultType);
4601 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy);
4605 static bool TryOCLSamplerInitialization(Sema &S,
4606 InitializationSequence &Sequence,
4608 Expr *Initializer) {
4609 if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() ||
4610 !Initializer->isIntegerConstantExpr(S.getASTContext()))
4613 Sequence.AddOCLSamplerInitStep(DestType);
4618 // OpenCL 1.2 spec, s6.12.10
4620 // The event argument can also be used to associate the
4621 // async_work_group_copy with a previous async copy allowing
4622 // an event to be shared by multiple async copies; otherwise
4623 // event should be zero.
4625 static bool TryOCLZeroEventInitialization(Sema &S,
4626 InitializationSequence &Sequence,
4628 Expr *Initializer) {
4629 if (!S.getLangOpts().OpenCL || !DestType->isEventT() ||
4630 !Initializer->isIntegerConstantExpr(S.getASTContext()) ||
4631 (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0))
4634 Sequence.AddOCLZeroEventStep(DestType);
4638 InitializationSequence::InitializationSequence(Sema &S,
4639 const InitializedEntity &Entity,
4640 const InitializationKind &Kind,
4642 bool TopLevelOfInitList)
4643 : FailedCandidateSet(Kind.getLocation(), OverloadCandidateSet::CSK_Normal) {
4644 InitializeFrom(S, Entity, Kind, Args, TopLevelOfInitList);
4647 void InitializationSequence::InitializeFrom(Sema &S,
4648 const InitializedEntity &Entity,
4649 const InitializationKind &Kind,
4651 bool TopLevelOfInitList) {
4652 ASTContext &Context = S.Context;
4654 // Eliminate non-overload placeholder types in the arguments. We
4655 // need to do this before checking whether types are dependent
4656 // because lowering a pseudo-object expression might well give us
4657 // something of dependent type.
4658 for (unsigned I = 0, E = Args.size(); I != E; ++I)
4659 if (Args[I]->getType()->isNonOverloadPlaceholderType()) {
4660 // FIXME: should we be doing this here?
4661 ExprResult result = S.CheckPlaceholderExpr(Args[I]);
4662 if (result.isInvalid()) {
4663 SetFailed(FK_PlaceholderType);
4666 Args[I] = result.get();
4669 // C++0x [dcl.init]p16:
4670 // The semantics of initializers are as follows. The destination type is
4671 // the type of the object or reference being initialized and the source
4672 // type is the type of the initializer expression. The source type is not
4673 // defined when the initializer is a braced-init-list or when it is a
4674 // parenthesized list of expressions.
4675 QualType DestType = Entity.getType();
4677 if (DestType->isDependentType() ||
4678 Expr::hasAnyTypeDependentArguments(Args)) {
4679 SequenceKind = DependentSequence;
4683 // Almost everything is a normal sequence.
4684 setSequenceKind(NormalSequence);
4686 QualType SourceType;
4687 Expr *Initializer = nullptr;
4688 if (Args.size() == 1) {
4689 Initializer = Args[0];
4690 if (S.getLangOpts().ObjC1) {
4691 if (S.CheckObjCBridgeRelatedConversions(Initializer->getLocStart(),
4692 DestType, Initializer->getType(),
4694 S.ConversionToObjCStringLiteralCheck(DestType, Initializer))
4695 Args[0] = Initializer;
4697 if (!isa<InitListExpr>(Initializer))
4698 SourceType = Initializer->getType();
4701 // - If the initializer is a (non-parenthesized) braced-init-list, the
4702 // object is list-initialized (8.5.4).
4703 if (Kind.getKind() != InitializationKind::IK_Direct) {
4704 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) {
4705 TryListInitialization(S, Entity, Kind, InitList, *this);
4710 // - If the destination type is a reference type, see 8.5.3.
4711 if (DestType->isReferenceType()) {
4712 // C++0x [dcl.init.ref]p1:
4713 // A variable declared to be a T& or T&&, that is, "reference to type T"
4714 // (8.3.2), shall be initialized by an object, or function, of type T or
4715 // by an object that can be converted into a T.
4716 // (Therefore, multiple arguments are not permitted.)
4717 if (Args.size() != 1)
4718 SetFailed(FK_TooManyInitsForReference);
4720 TryReferenceInitialization(S, Entity, Kind, Args[0], *this);
4724 // - If the initializer is (), the object is value-initialized.
4725 if (Kind.getKind() == InitializationKind::IK_Value ||
4726 (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) {
4727 TryValueInitialization(S, Entity, Kind, *this);
4731 // Handle default initialization.
4732 if (Kind.getKind() == InitializationKind::IK_Default) {
4733 TryDefaultInitialization(S, Entity, Kind, *this);
4737 // - If the destination type is an array of characters, an array of
4738 // char16_t, an array of char32_t, or an array of wchar_t, and the
4739 // initializer is a string literal, see 8.5.2.
4740 // - Otherwise, if the destination type is an array, the program is
4742 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) {
4743 if (Initializer && isa<VariableArrayType>(DestAT)) {
4744 SetFailed(FK_VariableLengthArrayHasInitializer);
4749 switch (IsStringInit(Initializer, DestAT, Context)) {
4751 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this);
4753 case SIF_NarrowStringIntoWideChar:
4754 SetFailed(FK_NarrowStringIntoWideCharArray);
4756 case SIF_WideStringIntoChar:
4757 SetFailed(FK_WideStringIntoCharArray);
4759 case SIF_IncompatWideStringIntoWideChar:
4760 SetFailed(FK_IncompatWideStringIntoWideChar);
4767 // Note: as an GNU C extension, we allow initialization of an
4768 // array from a compound literal that creates an array of the same
4769 // type, so long as the initializer has no side effects.
4770 if (!S.getLangOpts().CPlusPlus && Initializer &&
4771 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) &&
4772 Initializer->getType()->isArrayType()) {
4773 const ArrayType *SourceAT
4774 = Context.getAsArrayType(Initializer->getType());
4775 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT))
4776 SetFailed(FK_ArrayTypeMismatch);
4777 else if (Initializer->HasSideEffects(S.Context))
4778 SetFailed(FK_NonConstantArrayInit);
4780 AddArrayInitStep(DestType);
4783 // Note: as a GNU C++ extension, we allow list-initialization of a
4784 // class member of array type from a parenthesized initializer list.
4785 else if (S.getLangOpts().CPlusPlus &&
4786 Entity.getKind() == InitializedEntity::EK_Member &&
4787 Initializer && isa<InitListExpr>(Initializer)) {
4788 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer),
4790 AddParenthesizedArrayInitStep(DestType);
4791 } else if (DestAT->getElementType()->isCharType())
4792 SetFailed(FK_ArrayNeedsInitListOrStringLiteral);
4793 else if (IsWideCharCompatible(DestAT->getElementType(), Context))
4794 SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral);
4796 SetFailed(FK_ArrayNeedsInitList);
4801 // Determine whether we should consider writeback conversions for
4803 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount &&
4804 Entity.isParameterKind();
4806 // We're at the end of the line for C: it's either a write-back conversion
4807 // or it's a C assignment. There's no need to check anything else.
4808 if (!S.getLangOpts().CPlusPlus) {
4809 // If allowed, check whether this is an Objective-C writeback conversion.
4810 if (allowObjCWritebackConversion &&
4811 tryObjCWritebackConversion(S, *this, Entity, Initializer)) {
4815 if (TryOCLSamplerInitialization(S, *this, DestType, Initializer))
4818 if (TryOCLZeroEventInitialization(S, *this, DestType, Initializer))
4821 // Handle initialization in C
4822 AddCAssignmentStep(DestType);
4823 MaybeProduceObjCObject(S, *this, Entity);
4827 assert(S.getLangOpts().CPlusPlus);
4829 // - If the destination type is a (possibly cv-qualified) class type:
4830 if (DestType->isRecordType()) {
4831 // - If the initialization is direct-initialization, or if it is
4832 // copy-initialization where the cv-unqualified version of the
4833 // source type is the same class as, or a derived class of, the
4834 // class of the destination, constructors are considered. [...]
4835 if (Kind.getKind() == InitializationKind::IK_Direct ||
4836 (Kind.getKind() == InitializationKind::IK_Copy &&
4837 (Context.hasSameUnqualifiedType(SourceType, DestType) ||
4838 S.IsDerivedFrom(SourceType, DestType))))
4839 TryConstructorInitialization(S, Entity, Kind, Args,
4841 // - Otherwise (i.e., for the remaining copy-initialization cases),
4842 // user-defined conversion sequences that can convert from the source
4843 // type to the destination type or (when a conversion function is
4844 // used) to a derived class thereof are enumerated as described in
4845 // 13.3.1.4, and the best one is chosen through overload resolution
4848 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
4849 TopLevelOfInitList);
4853 if (Args.size() > 1) {
4854 SetFailed(FK_TooManyInitsForScalar);
4857 assert(Args.size() == 1 && "Zero-argument case handled above");
4859 // - Otherwise, if the source type is a (possibly cv-qualified) class
4860 // type, conversion functions are considered.
4861 if (!SourceType.isNull() && SourceType->isRecordType()) {
4862 // For a conversion to _Atomic(T) from either T or a class type derived
4863 // from T, initialize the T object then convert to _Atomic type.
4864 bool NeedAtomicConversion = false;
4865 if (const AtomicType *Atomic = DestType->getAs<AtomicType>()) {
4866 if (Context.hasSameUnqualifiedType(SourceType, Atomic->getValueType()) ||
4867 S.IsDerivedFrom(SourceType, Atomic->getValueType())) {
4868 DestType = Atomic->getValueType();
4869 NeedAtomicConversion = true;
4873 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
4874 TopLevelOfInitList);
4875 MaybeProduceObjCObject(S, *this, Entity);
4876 if (!Failed() && NeedAtomicConversion)
4877 AddAtomicConversionStep(Entity.getType());
4881 // - Otherwise, the initial value of the object being initialized is the
4882 // (possibly converted) value of the initializer expression. Standard
4883 // conversions (Clause 4) will be used, if necessary, to convert the
4884 // initializer expression to the cv-unqualified version of the
4885 // destination type; no user-defined conversions are considered.
4887 ImplicitConversionSequence ICS
4888 = S.TryImplicitConversion(Initializer, DestType,
4889 /*SuppressUserConversions*/true,
4890 /*AllowExplicitConversions*/ false,
4891 /*InOverloadResolution*/ false,
4892 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
4893 allowObjCWritebackConversion);
4895 if (ICS.isStandard() &&
4896 ICS.Standard.Second == ICK_Writeback_Conversion) {
4897 // Objective-C ARC writeback conversion.
4899 // We should copy unless we're passing to an argument explicitly
4901 bool ShouldCopy = true;
4902 if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
4903 ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
4905 // If there was an lvalue adjustment, add it as a separate conversion.
4906 if (ICS.Standard.First == ICK_Array_To_Pointer ||
4907 ICS.Standard.First == ICK_Lvalue_To_Rvalue) {
4908 ImplicitConversionSequence LvalueICS;
4909 LvalueICS.setStandard();
4910 LvalueICS.Standard.setAsIdentityConversion();
4911 LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0));
4912 LvalueICS.Standard.First = ICS.Standard.First;
4913 AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0));
4916 AddPassByIndirectCopyRestoreStep(DestType, ShouldCopy);
4917 } else if (ICS.isBad()) {
4919 if (isLibstdcxxPointerReturnFalseHack(S, Entity, Initializer)) {
4920 AddZeroInitializationStep(Entity.getType());
4921 } else if (Initializer->getType() == Context.OverloadTy &&
4922 !S.ResolveAddressOfOverloadedFunction(Initializer, DestType,
4924 SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4926 SetFailed(InitializationSequence::FK_ConversionFailed);
4928 AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
4930 MaybeProduceObjCObject(S, *this, Entity);
4934 InitializationSequence::~InitializationSequence() {
4935 for (SmallVectorImpl<Step>::iterator Step = Steps.begin(),
4936 StepEnd = Steps.end();
4937 Step != StepEnd; ++Step)
4941 //===----------------------------------------------------------------------===//
4942 // Perform initialization
4943 //===----------------------------------------------------------------------===//
4944 static Sema::AssignmentAction
4945 getAssignmentAction(const InitializedEntity &Entity, bool Diagnose = false) {
4946 switch(Entity.getKind()) {
4947 case InitializedEntity::EK_Variable:
4948 case InitializedEntity::EK_New:
4949 case InitializedEntity::EK_Exception:
4950 case InitializedEntity::EK_Base:
4951 case InitializedEntity::EK_Delegating:
4952 return Sema::AA_Initializing;
4954 case InitializedEntity::EK_Parameter:
4955 if (Entity.getDecl() &&
4956 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
4957 return Sema::AA_Sending;
4959 return Sema::AA_Passing;
4961 case InitializedEntity::EK_Parameter_CF_Audited:
4962 if (Entity.getDecl() &&
4963 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
4964 return Sema::AA_Sending;
4966 return !Diagnose ? Sema::AA_Passing : Sema::AA_Passing_CFAudited;
4968 case InitializedEntity::EK_Result:
4969 return Sema::AA_Returning;
4971 case InitializedEntity::EK_Temporary:
4972 case InitializedEntity::EK_RelatedResult:
4973 // FIXME: Can we tell apart casting vs. converting?
4974 return Sema::AA_Casting;
4976 case InitializedEntity::EK_Member:
4977 case InitializedEntity::EK_ArrayElement:
4978 case InitializedEntity::EK_VectorElement:
4979 case InitializedEntity::EK_ComplexElement:
4980 case InitializedEntity::EK_BlockElement:
4981 case InitializedEntity::EK_LambdaCapture:
4982 case InitializedEntity::EK_CompoundLiteralInit:
4983 return Sema::AA_Initializing;
4986 llvm_unreachable("Invalid EntityKind!");
4989 /// \brief Whether we should bind a created object as a temporary when
4990 /// initializing the given entity.
4991 static bool shouldBindAsTemporary(const InitializedEntity &Entity) {
4992 switch (Entity.getKind()) {
4993 case InitializedEntity::EK_ArrayElement:
4994 case InitializedEntity::EK_Member:
4995 case InitializedEntity::EK_Result:
4996 case InitializedEntity::EK_New:
4997 case InitializedEntity::EK_Variable:
4998 case InitializedEntity::EK_Base:
4999 case InitializedEntity::EK_Delegating:
5000 case InitializedEntity::EK_VectorElement:
5001 case InitializedEntity::EK_ComplexElement:
5002 case InitializedEntity::EK_Exception:
5003 case InitializedEntity::EK_BlockElement:
5004 case InitializedEntity::EK_LambdaCapture:
5005 case InitializedEntity::EK_CompoundLiteralInit:
5008 case InitializedEntity::EK_Parameter:
5009 case InitializedEntity::EK_Parameter_CF_Audited:
5010 case InitializedEntity::EK_Temporary:
5011 case InitializedEntity::EK_RelatedResult:
5015 llvm_unreachable("missed an InitializedEntity kind?");
5018 /// \brief Whether the given entity, when initialized with an object
5019 /// created for that initialization, requires destruction.
5020 static bool shouldDestroyTemporary(const InitializedEntity &Entity) {
5021 switch (Entity.getKind()) {
5022 case InitializedEntity::EK_Result:
5023 case InitializedEntity::EK_New:
5024 case InitializedEntity::EK_Base:
5025 case InitializedEntity::EK_Delegating:
5026 case InitializedEntity::EK_VectorElement:
5027 case InitializedEntity::EK_ComplexElement:
5028 case InitializedEntity::EK_BlockElement:
5029 case InitializedEntity::EK_LambdaCapture:
5032 case InitializedEntity::EK_Member:
5033 case InitializedEntity::EK_Variable:
5034 case InitializedEntity::EK_Parameter:
5035 case InitializedEntity::EK_Parameter_CF_Audited:
5036 case InitializedEntity::EK_Temporary:
5037 case InitializedEntity::EK_ArrayElement:
5038 case InitializedEntity::EK_Exception:
5039 case InitializedEntity::EK_CompoundLiteralInit:
5040 case InitializedEntity::EK_RelatedResult:
5044 llvm_unreachable("missed an InitializedEntity kind?");
5047 /// \brief Look for copy and move constructors and constructor templates, for
5048 /// copying an object via direct-initialization (per C++11 [dcl.init]p16).
5049 static void LookupCopyAndMoveConstructors(Sema &S,
5050 OverloadCandidateSet &CandidateSet,
5051 CXXRecordDecl *Class,
5052 Expr *CurInitExpr) {
5053 DeclContext::lookup_result R = S.LookupConstructors(Class);
5054 // The container holding the constructors can under certain conditions
5055 // be changed while iterating (e.g. because of deserialization).
5056 // To be safe we copy the lookup results to a new container.
5057 SmallVector<NamedDecl*, 16> Ctors(R.begin(), R.end());
5058 for (SmallVectorImpl<NamedDecl *>::iterator
5059 CI = Ctors.begin(), CE = Ctors.end(); CI != CE; ++CI) {
5061 CXXConstructorDecl *Constructor = nullptr;
5063 if ((Constructor = dyn_cast<CXXConstructorDecl>(D))) {
5064 // Handle copy/moveconstructors, only.
5065 if (!Constructor || Constructor->isInvalidDecl() ||
5066 !Constructor->isCopyOrMoveConstructor() ||
5067 !Constructor->isConvertingConstructor(/*AllowExplicit=*/true))
5070 DeclAccessPair FoundDecl
5071 = DeclAccessPair::make(Constructor, Constructor->getAccess());
5072 S.AddOverloadCandidate(Constructor, FoundDecl,
5073 CurInitExpr, CandidateSet);
5077 // Handle constructor templates.
5078 FunctionTemplateDecl *ConstructorTmpl = cast<FunctionTemplateDecl>(D);
5079 if (ConstructorTmpl->isInvalidDecl())
5082 Constructor = cast<CXXConstructorDecl>(
5083 ConstructorTmpl->getTemplatedDecl());
5084 if (!Constructor->isConvertingConstructor(/*AllowExplicit=*/true))
5087 // FIXME: Do we need to limit this to copy-constructor-like
5089 DeclAccessPair FoundDecl
5090 = DeclAccessPair::make(ConstructorTmpl, ConstructorTmpl->getAccess());
5091 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, nullptr,
5092 CurInitExpr, CandidateSet, true);
5096 /// \brief Get the location at which initialization diagnostics should appear.
5097 static SourceLocation getInitializationLoc(const InitializedEntity &Entity,
5098 Expr *Initializer) {
5099 switch (Entity.getKind()) {
5100 case InitializedEntity::EK_Result:
5101 return Entity.getReturnLoc();
5103 case InitializedEntity::EK_Exception:
5104 return Entity.getThrowLoc();
5106 case InitializedEntity::EK_Variable:
5107 return Entity.getDecl()->getLocation();
5109 case InitializedEntity::EK_LambdaCapture:
5110 return Entity.getCaptureLoc();
5112 case InitializedEntity::EK_ArrayElement:
5113 case InitializedEntity::EK_Member:
5114 case InitializedEntity::EK_Parameter:
5115 case InitializedEntity::EK_Parameter_CF_Audited:
5116 case InitializedEntity::EK_Temporary:
5117 case InitializedEntity::EK_New:
5118 case InitializedEntity::EK_Base:
5119 case InitializedEntity::EK_Delegating:
5120 case InitializedEntity::EK_VectorElement:
5121 case InitializedEntity::EK_ComplexElement:
5122 case InitializedEntity::EK_BlockElement:
5123 case InitializedEntity::EK_CompoundLiteralInit:
5124 case InitializedEntity::EK_RelatedResult:
5125 return Initializer->getLocStart();
5127 llvm_unreachable("missed an InitializedEntity kind?");
5130 /// \brief Make a (potentially elidable) temporary copy of the object
5131 /// provided by the given initializer by calling the appropriate copy
5134 /// \param S The Sema object used for type-checking.
5136 /// \param T The type of the temporary object, which must either be
5137 /// the type of the initializer expression or a superclass thereof.
5139 /// \param Entity The entity being initialized.
5141 /// \param CurInit The initializer expression.
5143 /// \param IsExtraneousCopy Whether this is an "extraneous" copy that
5144 /// is permitted in C++03 (but not C++0x) when binding a reference to
5147 /// \returns An expression that copies the initializer expression into
5148 /// a temporary object, or an error expression if a copy could not be
5150 static ExprResult CopyObject(Sema &S,
5152 const InitializedEntity &Entity,
5154 bool IsExtraneousCopy) {
5155 if (CurInit.isInvalid())
5157 // Determine which class type we're copying to.
5158 Expr *CurInitExpr = (Expr *)CurInit.get();
5159 CXXRecordDecl *Class = nullptr;
5160 if (const RecordType *Record = T->getAs<RecordType>())
5161 Class = cast<CXXRecordDecl>(Record->getDecl());
5165 // C++0x [class.copy]p32:
5166 // When certain criteria are met, an implementation is allowed to
5167 // omit the copy/move construction of a class object, even if the
5168 // copy/move constructor and/or destructor for the object have
5169 // side effects. [...]
5170 // - when a temporary class object that has not been bound to a
5171 // reference (12.2) would be copied/moved to a class object
5172 // with the same cv-unqualified type, the copy/move operation
5173 // can be omitted by constructing the temporary object
5174 // directly into the target of the omitted copy/move
5176 // Note that the other three bullets are handled elsewhere. Copy
5177 // elision for return statements and throw expressions are handled as part
5178 // of constructor initialization, while copy elision for exception handlers
5179 // is handled by the run-time.
5180 bool Elidable = CurInitExpr->isTemporaryObject(S.Context, Class);
5181 SourceLocation Loc = getInitializationLoc(Entity, CurInit.get());
5183 // Make sure that the type we are copying is complete.
5184 if (S.RequireCompleteType(Loc, T, diag::err_temp_copy_incomplete))
5187 // Perform overload resolution using the class's copy/move constructors.
5188 // Only consider constructors and constructor templates. Per
5189 // C++0x [dcl.init]p16, second bullet to class types, this initialization
5190 // is direct-initialization.
5191 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5192 LookupCopyAndMoveConstructors(S, CandidateSet, Class, CurInitExpr);
5194 bool HadMultipleCandidates = (CandidateSet.size() > 1);
5196 OverloadCandidateSet::iterator Best;
5197 switch (CandidateSet.BestViableFunction(S, Loc, Best)) {
5201 case OR_No_Viable_Function:
5202 S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext()
5203 ? diag::ext_rvalue_to_reference_temp_copy_no_viable
5204 : diag::err_temp_copy_no_viable)
5205 << (int)Entity.getKind() << CurInitExpr->getType()
5206 << CurInitExpr->getSourceRange();
5207 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr);
5208 if (!IsExtraneousCopy || S.isSFINAEContext())
5213 S.Diag(Loc, diag::err_temp_copy_ambiguous)
5214 << (int)Entity.getKind() << CurInitExpr->getType()
5215 << CurInitExpr->getSourceRange();
5216 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr);
5220 S.Diag(Loc, diag::err_temp_copy_deleted)
5221 << (int)Entity.getKind() << CurInitExpr->getType()
5222 << CurInitExpr->getSourceRange();
5223 S.NoteDeletedFunction(Best->Function);
5227 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function);
5228 SmallVector<Expr*, 8> ConstructorArgs;
5229 CurInit.get(); // Ownership transferred into MultiExprArg, below.
5231 S.CheckConstructorAccess(Loc, Constructor, Entity,
5232 Best->FoundDecl.getAccess(), IsExtraneousCopy);
5234 if (IsExtraneousCopy) {
5235 // If this is a totally extraneous copy for C++03 reference
5236 // binding purposes, just return the original initialization
5237 // expression. We don't generate an (elided) copy operation here
5238 // because doing so would require us to pass down a flag to avoid
5239 // infinite recursion, where each step adds another extraneous,
5242 // Instantiate the default arguments of any extra parameters in
5243 // the selected copy constructor, as if we were going to create a
5244 // proper call to the copy constructor.
5245 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) {
5246 ParmVarDecl *Parm = Constructor->getParamDecl(I);
5247 if (S.RequireCompleteType(Loc, Parm->getType(),
5248 diag::err_call_incomplete_argument))
5251 // Build the default argument expression; we don't actually care
5252 // if this succeeds or not, because this routine will complain
5253 // if there was a problem.
5254 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm);
5260 // Determine the arguments required to actually perform the
5261 // constructor call (we might have derived-to-base conversions, or
5262 // the copy constructor may have default arguments).
5263 if (S.CompleteConstructorCall(Constructor, CurInitExpr, Loc, ConstructorArgs))
5266 // Actually perform the constructor call.
5267 CurInit = S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable,
5269 HadMultipleCandidates,
5271 /*StdInitListInit*/ false,
5273 CXXConstructExpr::CK_Complete,
5276 // If we're supposed to bind temporaries, do so.
5277 if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity))
5278 CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
5282 /// \brief Check whether elidable copy construction for binding a reference to
5283 /// a temporary would have succeeded if we were building in C++98 mode, for
5285 static void CheckCXX98CompatAccessibleCopy(Sema &S,
5286 const InitializedEntity &Entity,
5287 Expr *CurInitExpr) {
5288 assert(S.getLangOpts().CPlusPlus11);
5290 const RecordType *Record = CurInitExpr->getType()->getAs<RecordType>();
5294 SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr);
5295 if (S.Diags.isIgnored(diag::warn_cxx98_compat_temp_copy, Loc))
5298 // Find constructors which would have been considered.
5299 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5300 LookupCopyAndMoveConstructors(
5301 S, CandidateSet, cast<CXXRecordDecl>(Record->getDecl()), CurInitExpr);
5303 // Perform overload resolution.
5304 OverloadCandidateSet::iterator Best;
5305 OverloadingResult OR = CandidateSet.BestViableFunction(S, Loc, Best);
5307 PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy)
5308 << OR << (int)Entity.getKind() << CurInitExpr->getType()
5309 << CurInitExpr->getSourceRange();
5313 S.CheckConstructorAccess(Loc, cast<CXXConstructorDecl>(Best->Function),
5314 Entity, Best->FoundDecl.getAccess(), Diag);
5315 // FIXME: Check default arguments as far as that's possible.
5318 case OR_No_Viable_Function:
5320 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr);
5325 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr);
5330 S.NoteDeletedFunction(Best->Function);
5335 void InitializationSequence::PrintInitLocationNote(Sema &S,
5336 const InitializedEntity &Entity) {
5337 if (Entity.isParameterKind() && Entity.getDecl()) {
5338 if (Entity.getDecl()->getLocation().isInvalid())
5341 if (Entity.getDecl()->getDeclName())
5342 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here)
5343 << Entity.getDecl()->getDeclName();
5345 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here);
5347 else if (Entity.getKind() == InitializedEntity::EK_RelatedResult &&
5348 Entity.getMethodDecl())
5349 S.Diag(Entity.getMethodDecl()->getLocation(),
5350 diag::note_method_return_type_change)
5351 << Entity.getMethodDecl()->getDeclName();
5354 static bool isReferenceBinding(const InitializationSequence::Step &s) {
5355 return s.Kind == InitializationSequence::SK_BindReference ||
5356 s.Kind == InitializationSequence::SK_BindReferenceToTemporary;
5359 /// Returns true if the parameters describe a constructor initialization of
5360 /// an explicit temporary object, e.g. "Point(x, y)".
5361 static bool isExplicitTemporary(const InitializedEntity &Entity,
5362 const InitializationKind &Kind,
5364 switch (Entity.getKind()) {
5365 case InitializedEntity::EK_Temporary:
5366 case InitializedEntity::EK_CompoundLiteralInit:
5367 case InitializedEntity::EK_RelatedResult:
5373 switch (Kind.getKind()) {
5374 case InitializationKind::IK_DirectList:
5376 // FIXME: Hack to work around cast weirdness.
5377 case InitializationKind::IK_Direct:
5378 case InitializationKind::IK_Value:
5379 return NumArgs != 1;
5386 PerformConstructorInitialization(Sema &S,
5387 const InitializedEntity &Entity,
5388 const InitializationKind &Kind,
5390 const InitializationSequence::Step& Step,
5391 bool &ConstructorInitRequiresZeroInit,
5392 bool IsListInitialization,
5393 bool IsStdInitListInitialization,
5394 SourceLocation LBraceLoc,
5395 SourceLocation RBraceLoc) {
5396 unsigned NumArgs = Args.size();
5397 CXXConstructorDecl *Constructor
5398 = cast<CXXConstructorDecl>(Step.Function.Function);
5399 bool HadMultipleCandidates = Step.Function.HadMultipleCandidates;
5401 // Build a call to the selected constructor.
5402 SmallVector<Expr*, 8> ConstructorArgs;
5403 SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid())
5404 ? Kind.getEqualLoc()
5405 : Kind.getLocation();
5407 if (Kind.getKind() == InitializationKind::IK_Default) {
5408 // Force even a trivial, implicit default constructor to be
5409 // semantically checked. We do this explicitly because we don't build
5410 // the definition for completely trivial constructors.
5411 assert(Constructor->getParent() && "No parent class for constructor.");
5412 if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
5413 Constructor->isTrivial() && !Constructor->isUsed(false))
5414 S.DefineImplicitDefaultConstructor(Loc, Constructor);
5417 ExprResult CurInit((Expr *)nullptr);
5419 // C++ [over.match.copy]p1:
5420 // - When initializing a temporary to be bound to the first parameter
5421 // of a constructor that takes a reference to possibly cv-qualified
5422 // T as its first argument, called with a single argument in the
5423 // context of direct-initialization, explicit conversion functions
5424 // are also considered.
5425 bool AllowExplicitConv = Kind.AllowExplicit() && !Kind.isCopyInit() &&
5427 Constructor->isCopyOrMoveConstructor();
5429 // Determine the arguments required to actually perform the constructor
5431 if (S.CompleteConstructorCall(Constructor, Args,
5432 Loc, ConstructorArgs,
5434 IsListInitialization))
5438 if (isExplicitTemporary(Entity, Kind, NumArgs)) {
5439 // An explicitly-constructed temporary, e.g., X(1, 2).
5440 S.MarkFunctionReferenced(Loc, Constructor);
5441 if (S.DiagnoseUseOfDecl(Constructor, Loc))
5444 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
5446 TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc);
5447 SourceRange ParenOrBraceRange =
5448 (Kind.getKind() == InitializationKind::IK_DirectList)
5449 ? SourceRange(LBraceLoc, RBraceLoc)
5450 : Kind.getParenRange();
5452 CurInit = new (S.Context) CXXTemporaryObjectExpr(
5453 S.Context, Constructor, TSInfo, ConstructorArgs, ParenOrBraceRange,
5454 HadMultipleCandidates, IsListInitialization,
5455 IsStdInitListInitialization, ConstructorInitRequiresZeroInit);
5457 CXXConstructExpr::ConstructionKind ConstructKind =
5458 CXXConstructExpr::CK_Complete;
5460 if (Entity.getKind() == InitializedEntity::EK_Base) {
5461 ConstructKind = Entity.getBaseSpecifier()->isVirtual() ?
5462 CXXConstructExpr::CK_VirtualBase :
5463 CXXConstructExpr::CK_NonVirtualBase;
5464 } else if (Entity.getKind() == InitializedEntity::EK_Delegating) {
5465 ConstructKind = CXXConstructExpr::CK_Delegating;
5468 // Only get the parenthesis or brace range if it is a list initialization or
5469 // direct construction.
5470 SourceRange ParenOrBraceRange;
5471 if (IsListInitialization)
5472 ParenOrBraceRange = SourceRange(LBraceLoc, RBraceLoc);
5473 else if (Kind.getKind() == InitializationKind::IK_Direct)
5474 ParenOrBraceRange = Kind.getParenRange();
5476 // If the entity allows NRVO, mark the construction as elidable
5478 if (Entity.allowsNRVO())
5479 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(),
5480 Constructor, /*Elidable=*/true,
5482 HadMultipleCandidates,
5483 IsListInitialization,
5484 IsStdInitListInitialization,
5485 ConstructorInitRequiresZeroInit,
5489 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(),
5492 HadMultipleCandidates,
5493 IsListInitialization,
5494 IsStdInitListInitialization,
5495 ConstructorInitRequiresZeroInit,
5499 if (CurInit.isInvalid())
5502 // Only check access if all of that succeeded.
5503 S.CheckConstructorAccess(Loc, Constructor, Entity,
5504 Step.Function.FoundDecl.getAccess());
5505 if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc))
5508 if (shouldBindAsTemporary(Entity))
5509 CurInit = S.MaybeBindToTemporary(CurInit.get());
5514 /// Determine whether the specified InitializedEntity definitely has a lifetime
5515 /// longer than the current full-expression. Conservatively returns false if
5518 InitializedEntityOutlivesFullExpression(const InitializedEntity &Entity) {
5519 const InitializedEntity *Top = &Entity;
5520 while (Top->getParent())
5521 Top = Top->getParent();
5523 switch (Top->getKind()) {
5524 case InitializedEntity::EK_Variable:
5525 case InitializedEntity::EK_Result:
5526 case InitializedEntity::EK_Exception:
5527 case InitializedEntity::EK_Member:
5528 case InitializedEntity::EK_New:
5529 case InitializedEntity::EK_Base:
5530 case InitializedEntity::EK_Delegating:
5533 case InitializedEntity::EK_ArrayElement:
5534 case InitializedEntity::EK_VectorElement:
5535 case InitializedEntity::EK_BlockElement:
5536 case InitializedEntity::EK_ComplexElement:
5537 // Could not determine what the full initialization is. Assume it might not
5538 // outlive the full-expression.
5541 case InitializedEntity::EK_Parameter:
5542 case InitializedEntity::EK_Parameter_CF_Audited:
5543 case InitializedEntity::EK_Temporary:
5544 case InitializedEntity::EK_LambdaCapture:
5545 case InitializedEntity::EK_CompoundLiteralInit:
5546 case InitializedEntity::EK_RelatedResult:
5547 // The entity being initialized might not outlive the full-expression.
5551 llvm_unreachable("unknown entity kind");
5554 /// Determine the declaration which an initialized entity ultimately refers to,
5555 /// for the purpose of lifetime-extending a temporary bound to a reference in
5556 /// the initialization of \p Entity.
5557 static const InitializedEntity *getEntityForTemporaryLifetimeExtension(
5558 const InitializedEntity *Entity,
5559 const InitializedEntity *FallbackDecl = nullptr) {
5560 // C++11 [class.temporary]p5:
5561 switch (Entity->getKind()) {
5562 case InitializedEntity::EK_Variable:
5563 // The temporary [...] persists for the lifetime of the reference
5566 case InitializedEntity::EK_Member:
5567 // For subobjects, we look at the complete object.
5568 if (Entity->getParent())
5569 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
5573 // -- A temporary bound to a reference member in a constructor's
5574 // ctor-initializer persists until the constructor exits.
5577 case InitializedEntity::EK_Parameter:
5578 case InitializedEntity::EK_Parameter_CF_Audited:
5579 // -- A temporary bound to a reference parameter in a function call
5580 // persists until the completion of the full-expression containing
5582 case InitializedEntity::EK_Result:
5583 // -- The lifetime of a temporary bound to the returned value in a
5584 // function return statement is not extended; the temporary is
5585 // destroyed at the end of the full-expression in the return statement.
5586 case InitializedEntity::EK_New:
5587 // -- A temporary bound to a reference in a new-initializer persists
5588 // until the completion of the full-expression containing the
5592 case InitializedEntity::EK_Temporary:
5593 case InitializedEntity::EK_CompoundLiteralInit:
5594 case InitializedEntity::EK_RelatedResult:
5595 // We don't yet know the storage duration of the surrounding temporary.
5596 // Assume it's got full-expression duration for now, it will patch up our
5597 // storage duration if that's not correct.
5600 case InitializedEntity::EK_ArrayElement:
5601 // For subobjects, we look at the complete object.
5602 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
5605 case InitializedEntity::EK_Base:
5606 case InitializedEntity::EK_Delegating:
5607 // We can reach this case for aggregate initialization in a constructor:
5608 // struct A { int &&r; };
5609 // struct B : A { B() : A{0} {} };
5610 // In this case, use the innermost field decl as the context.
5611 return FallbackDecl;
5613 case InitializedEntity::EK_BlockElement:
5614 case InitializedEntity::EK_LambdaCapture:
5615 case InitializedEntity::EK_Exception:
5616 case InitializedEntity::EK_VectorElement:
5617 case InitializedEntity::EK_ComplexElement:
5620 llvm_unreachable("unknown entity kind");
5623 static void performLifetimeExtension(Expr *Init,
5624 const InitializedEntity *ExtendingEntity);
5626 /// Update a glvalue expression that is used as the initializer of a reference
5627 /// to note that its lifetime is extended.
5628 /// \return \c true if any temporary had its lifetime extended.
5630 performReferenceExtension(Expr *Init,
5631 const InitializedEntity *ExtendingEntity) {
5632 // Walk past any constructs which we can lifetime-extend across.
5637 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
5638 if (ILE->getNumInits() == 1 && ILE->isGLValue()) {
5639 // This is just redundant braces around an initializer. Step over it.
5640 Init = ILE->getInit(0);
5644 // Step over any subobject adjustments; we may have a materialized
5645 // temporary inside them.
5646 SmallVector<const Expr *, 2> CommaLHSs;
5647 SmallVector<SubobjectAdjustment, 2> Adjustments;
5648 Init = const_cast<Expr *>(
5649 Init->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments));
5651 // Per current approach for DR1376, look through casts to reference type
5652 // when performing lifetime extension.
5653 if (CastExpr *CE = dyn_cast<CastExpr>(Init))
5654 if (CE->getSubExpr()->isGLValue())
5655 Init = CE->getSubExpr();
5657 // FIXME: Per DR1213, subscripting on an array temporary produces an xvalue.
5658 // It's unclear if binding a reference to that xvalue extends the array
5660 } while (Init != Old);
5662 if (MaterializeTemporaryExpr *ME = dyn_cast<MaterializeTemporaryExpr>(Init)) {
5663 // Update the storage duration of the materialized temporary.
5664 // FIXME: Rebuild the expression instead of mutating it.
5665 ME->setExtendingDecl(ExtendingEntity->getDecl(),
5666 ExtendingEntity->allocateManglingNumber());
5667 performLifetimeExtension(ME->GetTemporaryExpr(), ExtendingEntity);
5674 /// Update a prvalue expression that is going to be materialized as a
5675 /// lifetime-extended temporary.
5676 static void performLifetimeExtension(Expr *Init,
5677 const InitializedEntity *ExtendingEntity) {
5678 // Dig out the expression which constructs the extended temporary.
5679 SmallVector<const Expr *, 2> CommaLHSs;
5680 SmallVector<SubobjectAdjustment, 2> Adjustments;
5681 Init = const_cast<Expr *>(
5682 Init->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments));
5684 if (CXXBindTemporaryExpr *BTE = dyn_cast<CXXBindTemporaryExpr>(Init))
5685 Init = BTE->getSubExpr();
5687 if (CXXStdInitializerListExpr *ILE =
5688 dyn_cast<CXXStdInitializerListExpr>(Init)) {
5689 performReferenceExtension(ILE->getSubExpr(), ExtendingEntity);
5693 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
5694 if (ILE->getType()->isArrayType()) {
5695 for (unsigned I = 0, N = ILE->getNumInits(); I != N; ++I)
5696 performLifetimeExtension(ILE->getInit(I), ExtendingEntity);
5700 if (CXXRecordDecl *RD = ILE->getType()->getAsCXXRecordDecl()) {
5701 assert(RD->isAggregate() && "aggregate init on non-aggregate");
5703 // If we lifetime-extend a braced initializer which is initializing an
5704 // aggregate, and that aggregate contains reference members which are
5705 // bound to temporaries, those temporaries are also lifetime-extended.
5706 if (RD->isUnion() && ILE->getInitializedFieldInUnion() &&
5707 ILE->getInitializedFieldInUnion()->getType()->isReferenceType())
5708 performReferenceExtension(ILE->getInit(0), ExtendingEntity);
5711 for (const auto *I : RD->fields()) {
5712 if (Index >= ILE->getNumInits())
5714 if (I->isUnnamedBitfield())
5716 Expr *SubInit = ILE->getInit(Index);
5717 if (I->getType()->isReferenceType())
5718 performReferenceExtension(SubInit, ExtendingEntity);
5719 else if (isa<InitListExpr>(SubInit) ||
5720 isa<CXXStdInitializerListExpr>(SubInit))
5721 // This may be either aggregate-initialization of a member or
5722 // initialization of a std::initializer_list object. Either way,
5723 // we should recursively lifetime-extend that initializer.
5724 performLifetimeExtension(SubInit, ExtendingEntity);
5732 static void warnOnLifetimeExtension(Sema &S, const InitializedEntity &Entity,
5733 const Expr *Init, bool IsInitializerList,
5734 const ValueDecl *ExtendingDecl) {
5735 // Warn if a field lifetime-extends a temporary.
5736 if (isa<FieldDecl>(ExtendingDecl)) {
5737 if (IsInitializerList) {
5738 S.Diag(Init->getExprLoc(), diag::warn_dangling_std_initializer_list)
5739 << /*at end of constructor*/true;
5743 bool IsSubobjectMember = false;
5744 for (const InitializedEntity *Ent = Entity.getParent(); Ent;
5745 Ent = Ent->getParent()) {
5746 if (Ent->getKind() != InitializedEntity::EK_Base) {
5747 IsSubobjectMember = true;
5751 S.Diag(Init->getExprLoc(),
5752 diag::warn_bind_ref_member_to_temporary)
5753 << ExtendingDecl << Init->getSourceRange()
5754 << IsSubobjectMember << IsInitializerList;
5755 if (IsSubobjectMember)
5756 S.Diag(ExtendingDecl->getLocation(),
5757 diag::note_ref_subobject_of_member_declared_here);
5759 S.Diag(ExtendingDecl->getLocation(),
5760 diag::note_ref_or_ptr_member_declared_here)
5761 << /*is pointer*/false;
5765 static void DiagnoseNarrowingInInitList(Sema &S,
5766 const ImplicitConversionSequence &ICS,
5767 QualType PreNarrowingType,
5768 QualType EntityType,
5769 const Expr *PostInit);
5771 /// Provide warnings when std::move is used on construction.
5772 static void CheckMoveOnConstruction(Sema &S, const Expr *InitExpr,
5773 bool IsReturnStmt) {
5777 QualType DestType = InitExpr->getType();
5778 if (!DestType->isRecordType())
5781 unsigned DiagID = 0;
5783 const CXXConstructExpr *CCE =
5784 dyn_cast<CXXConstructExpr>(InitExpr->IgnoreParens());
5785 if (!CCE || CCE->getNumArgs() != 1)
5788 if (!CCE->getConstructor()->isCopyOrMoveConstructor())
5791 InitExpr = CCE->getArg(0)->IgnoreImpCasts();
5793 // Remove implicit temporary and constructor nodes.
5794 if (const MaterializeTemporaryExpr *MTE =
5795 dyn_cast<MaterializeTemporaryExpr>(InitExpr)) {
5796 InitExpr = MTE->GetTemporaryExpr()->IgnoreImpCasts();
5797 while (const CXXConstructExpr *CCE =
5798 dyn_cast<CXXConstructExpr>(InitExpr)) {
5799 if (isa<CXXTemporaryObjectExpr>(CCE))
5801 if (CCE->getNumArgs() == 0)
5803 if (CCE->getNumArgs() > 1 && !isa<CXXDefaultArgExpr>(CCE->getArg(1)))
5805 InitExpr = CCE->getArg(0);
5807 InitExpr = InitExpr->IgnoreImpCasts();
5808 DiagID = diag::warn_redundant_move_on_return;
5812 // Find the std::move call and get the argument.
5813 const CallExpr *CE = dyn_cast<CallExpr>(InitExpr->IgnoreParens());
5814 if (!CE || CE->getNumArgs() != 1)
5817 const FunctionDecl *MoveFunction = CE->getDirectCallee();
5818 if (!MoveFunction || !MoveFunction->isInStdNamespace() ||
5819 !MoveFunction->getIdentifier() ||
5820 !MoveFunction->getIdentifier()->isStr("move"))
5823 const Expr *Arg = CE->getArg(0)->IgnoreImplicit();
5826 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg->IgnoreParenImpCasts());
5827 if (!DRE || DRE->refersToEnclosingVariableOrCapture())
5830 const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl());
5831 if (!VD || !VD->hasLocalStorage())
5834 if (!VD->getType()->isRecordType())
5838 DiagID = S.Context.hasSameUnqualifiedType(DestType, VD->getType())
5839 ? diag::warn_pessimizing_move_on_return
5840 : diag::warn_redundant_move_on_return;
5843 DiagID = diag::warn_pessimizing_move_on_initialization;
5844 const Expr *ArgStripped = Arg->IgnoreImplicit()->IgnoreParens();
5845 if (!ArgStripped->isRValue() || !ArgStripped->getType()->isRecordType())
5849 S.Diag(CE->getLocStart(), DiagID);
5851 // Get all the locations for a fix-it. Don't emit the fix-it if any location
5852 // is within a macro.
5853 SourceLocation CallBegin = CE->getCallee()->getLocStart();
5854 if (CallBegin.isMacroID())
5856 SourceLocation RParen = CE->getRParenLoc();
5857 if (RParen.isMacroID())
5859 SourceLocation LParen;
5860 SourceLocation ArgLoc = Arg->getLocStart();
5862 // Special testing for the argument location. Since the fix-it needs the
5863 // location right before the argument, the argument location can be in a
5864 // macro only if it is at the beginning of the macro.
5865 while (ArgLoc.isMacroID() &&
5866 S.getSourceManager().isAtStartOfImmediateMacroExpansion(ArgLoc)) {
5867 ArgLoc = S.getSourceManager().getImmediateExpansionRange(ArgLoc).first;
5870 if (LParen.isMacroID())
5873 LParen = ArgLoc.getLocWithOffset(-1);
5875 S.Diag(CE->getLocStart(), diag::note_remove_move)
5876 << FixItHint::CreateRemoval(SourceRange(CallBegin, LParen))
5877 << FixItHint::CreateRemoval(SourceRange(RParen, RParen));
5881 InitializationSequence::Perform(Sema &S,
5882 const InitializedEntity &Entity,
5883 const InitializationKind &Kind,
5885 QualType *ResultType) {
5887 Diagnose(S, Entity, Kind, Args);
5890 if (!ZeroInitializationFixit.empty()) {
5891 unsigned DiagID = diag::err_default_init_const;
5892 if (Decl *D = Entity.getDecl())
5893 if (S.getLangOpts().MSVCCompat && D->hasAttr<SelectAnyAttr>())
5894 DiagID = diag::ext_default_init_const;
5896 // The initialization would have succeeded with this fixit. Since the fixit
5897 // is on the error, we need to build a valid AST in this case, so this isn't
5898 // handled in the Failed() branch above.
5899 QualType DestType = Entity.getType();
5900 S.Diag(Kind.getLocation(), DiagID)
5901 << DestType << (bool)DestType->getAs<RecordType>()
5902 << FixItHint::CreateInsertion(ZeroInitializationFixitLoc,
5903 ZeroInitializationFixit);
5906 if (getKind() == DependentSequence) {
5907 // If the declaration is a non-dependent, incomplete array type
5908 // that has an initializer, then its type will be completed once
5909 // the initializer is instantiated.
5910 if (ResultType && !Entity.getType()->isDependentType() &&
5912 QualType DeclType = Entity.getType();
5913 if (const IncompleteArrayType *ArrayT
5914 = S.Context.getAsIncompleteArrayType(DeclType)) {
5915 // FIXME: We don't currently have the ability to accurately
5916 // compute the length of an initializer list without
5917 // performing full type-checking of the initializer list
5918 // (since we have to determine where braces are implicitly
5919 // introduced and such). So, we fall back to making the array
5920 // type a dependently-sized array type with no specified
5922 if (isa<InitListExpr>((Expr *)Args[0])) {
5923 SourceRange Brackets;
5925 // Scavange the location of the brackets from the entity, if we can.
5926 if (DeclaratorDecl *DD = Entity.getDecl()) {
5927 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) {
5928 TypeLoc TL = TInfo->getTypeLoc();
5929 if (IncompleteArrayTypeLoc ArrayLoc =
5930 TL.getAs<IncompleteArrayTypeLoc>())
5931 Brackets = ArrayLoc.getBracketsRange();
5936 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(),
5937 /*NumElts=*/nullptr,
5938 ArrayT->getSizeModifier(),
5939 ArrayT->getIndexTypeCVRQualifiers(),
5945 if (Kind.getKind() == InitializationKind::IK_Direct &&
5946 !Kind.isExplicitCast()) {
5947 // Rebuild the ParenListExpr.
5948 SourceRange ParenRange = Kind.getParenRange();
5949 return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(),
5952 assert(Kind.getKind() == InitializationKind::IK_Copy ||
5953 Kind.isExplicitCast() ||
5954 Kind.getKind() == InitializationKind::IK_DirectList);
5955 return ExprResult(Args[0]);
5958 // No steps means no initialization.
5960 return ExprResult((Expr *)nullptr);
5962 if (S.getLangOpts().CPlusPlus11 && Entity.getType()->isReferenceType() &&
5963 Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
5964 !Entity.isParameterKind()) {
5965 // Produce a C++98 compatibility warning if we are initializing a reference
5966 // from an initializer list. For parameters, we produce a better warning
5968 Expr *Init = Args[0];
5969 S.Diag(Init->getLocStart(), diag::warn_cxx98_compat_reference_list_init)
5970 << Init->getSourceRange();
5973 // Diagnose cases where we initialize a pointer to an array temporary, and the
5974 // pointer obviously outlives the temporary.
5975 if (Args.size() == 1 && Args[0]->getType()->isArrayType() &&
5976 Entity.getType()->isPointerType() &&
5977 InitializedEntityOutlivesFullExpression(Entity)) {
5978 Expr *Init = Args[0];
5979 Expr::LValueClassification Kind = Init->ClassifyLValue(S.Context);
5980 if (Kind == Expr::LV_ClassTemporary || Kind == Expr::LV_ArrayTemporary)
5981 S.Diag(Init->getLocStart(), diag::warn_temporary_array_to_pointer_decay)
5982 << Init->getSourceRange();
5985 QualType DestType = Entity.getType().getNonReferenceType();
5986 // FIXME: Ugly hack around the fact that Entity.getType() is not
5987 // the same as Entity.getDecl()->getType() in cases involving type merging,
5988 // and we want latter when it makes sense.
5990 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() :
5993 ExprResult CurInit((Expr *)nullptr);
5995 // For initialization steps that start with a single initializer,
5996 // grab the only argument out the Args and place it into the "current"
5998 switch (Steps.front().Kind) {
5999 case SK_ResolveAddressOfOverloadedFunction:
6000 case SK_CastDerivedToBaseRValue:
6001 case SK_CastDerivedToBaseXValue:
6002 case SK_CastDerivedToBaseLValue:
6003 case SK_BindReference:
6004 case SK_BindReferenceToTemporary:
6005 case SK_ExtraneousCopyToTemporary:
6006 case SK_UserConversion:
6007 case SK_QualificationConversionLValue:
6008 case SK_QualificationConversionXValue:
6009 case SK_QualificationConversionRValue:
6010 case SK_AtomicConversion:
6011 case SK_LValueToRValue:
6012 case SK_ConversionSequence:
6013 case SK_ConversionSequenceNoNarrowing:
6014 case SK_ListInitialization:
6015 case SK_UnwrapInitList:
6016 case SK_RewrapInitList:
6017 case SK_CAssignment:
6019 case SK_ObjCObjectConversion:
6021 case SK_ParenthesizedArrayInit:
6022 case SK_PassByIndirectCopyRestore:
6023 case SK_PassByIndirectRestore:
6024 case SK_ProduceObjCObject:
6025 case SK_StdInitializerList:
6026 case SK_OCLSamplerInit:
6027 case SK_OCLZeroEvent: {
6028 assert(Args.size() == 1);
6030 if (!CurInit.get()) return ExprError();
6034 case SK_ConstructorInitialization:
6035 case SK_ConstructorInitializationFromList:
6036 case SK_StdInitializerListConstructorCall:
6037 case SK_ZeroInitialization:
6041 // Walk through the computed steps for the initialization sequence,
6042 // performing the specified conversions along the way.
6043 bool ConstructorInitRequiresZeroInit = false;
6044 for (step_iterator Step = step_begin(), StepEnd = step_end();
6045 Step != StepEnd; ++Step) {
6046 if (CurInit.isInvalid())
6049 QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType();
6051 switch (Step->Kind) {
6052 case SK_ResolveAddressOfOverloadedFunction:
6053 // Overload resolution determined which function invoke; update the
6054 // initializer to reflect that choice.
6055 S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl);
6056 if (S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()))
6058 CurInit = S.FixOverloadedFunctionReference(CurInit,
6059 Step->Function.FoundDecl,
6060 Step->Function.Function);
6063 case SK_CastDerivedToBaseRValue:
6064 case SK_CastDerivedToBaseXValue:
6065 case SK_CastDerivedToBaseLValue: {
6066 // We have a derived-to-base cast that produces either an rvalue or an
6067 // lvalue. Perform that cast.
6069 CXXCastPath BasePath;
6071 // Casts to inaccessible base classes are allowed with C-style casts.
6072 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast();
6073 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type,
6074 CurInit.get()->getLocStart(),
6075 CurInit.get()->getSourceRange(),
6076 &BasePath, IgnoreBaseAccess))
6080 Step->Kind == SK_CastDerivedToBaseLValue ?
6082 (Step->Kind == SK_CastDerivedToBaseXValue ?
6086 ImplicitCastExpr::Create(S.Context, Step->Type, CK_DerivedToBase,
6087 CurInit.get(), &BasePath, VK);
6091 case SK_BindReference:
6092 // References cannot bind to bit-fields (C++ [dcl.init.ref]p5).
6093 if (CurInit.get()->refersToBitField()) {
6094 // We don't necessarily have an unambiguous source bit-field.
6095 FieldDecl *BitField = CurInit.get()->getSourceBitField();
6096 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield)
6097 << Entity.getType().isVolatileQualified()
6098 << (BitField ? BitField->getDeclName() : DeclarationName())
6099 << (BitField != nullptr)
6100 << CurInit.get()->getSourceRange();
6102 S.Diag(BitField->getLocation(), diag::note_bitfield_decl);
6107 if (CurInit.get()->refersToVectorElement()) {
6108 // References cannot bind to vector elements.
6109 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element)
6110 << Entity.getType().isVolatileQualified()
6111 << CurInit.get()->getSourceRange();
6112 PrintInitLocationNote(S, Entity);
6116 // Reference binding does not have any corresponding ASTs.
6118 // Check exception specifications
6119 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
6122 // Even though we didn't materialize a temporary, the binding may still
6123 // extend the lifetime of a temporary. This happens if we bind a reference
6124 // to the result of a cast to reference type.
6125 if (const InitializedEntity *ExtendingEntity =
6126 getEntityForTemporaryLifetimeExtension(&Entity))
6127 if (performReferenceExtension(CurInit.get(), ExtendingEntity))
6128 warnOnLifetimeExtension(S, Entity, CurInit.get(),
6129 /*IsInitializerList=*/false,
6130 ExtendingEntity->getDecl());
6134 case SK_BindReferenceToTemporary: {
6135 // Make sure the "temporary" is actually an rvalue.
6136 assert(CurInit.get()->isRValue() && "not a temporary");
6138 // Check exception specifications
6139 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
6142 // Materialize the temporary into memory.
6143 MaterializeTemporaryExpr *MTE = new (S.Context) MaterializeTemporaryExpr(
6144 Entity.getType().getNonReferenceType(), CurInit.get(),
6145 Entity.getType()->isLValueReferenceType());
6147 // Maybe lifetime-extend the temporary's subobjects to match the
6148 // entity's lifetime.
6149 if (const InitializedEntity *ExtendingEntity =
6150 getEntityForTemporaryLifetimeExtension(&Entity))
6151 if (performReferenceExtension(MTE, ExtendingEntity))
6152 warnOnLifetimeExtension(S, Entity, CurInit.get(), /*IsInitializerList=*/false,
6153 ExtendingEntity->getDecl());
6155 // If we're binding to an Objective-C object that has lifetime, we
6156 // need cleanups. Likewise if we're extending this temporary to automatic
6157 // storage duration -- we need to register its cleanup during the
6158 // full-expression's cleanups.
6159 if ((S.getLangOpts().ObjCAutoRefCount &&
6160 MTE->getType()->isObjCLifetimeType()) ||
6161 (MTE->getStorageDuration() == SD_Automatic &&
6162 MTE->getType().isDestructedType()))
6163 S.ExprNeedsCleanups = true;
6169 case SK_ExtraneousCopyToTemporary:
6170 CurInit = CopyObject(S, Step->Type, Entity, CurInit,
6171 /*IsExtraneousCopy=*/true);
6174 case SK_UserConversion: {
6175 // We have a user-defined conversion that invokes either a constructor
6176 // or a conversion function.
6178 bool IsCopy = false;
6179 FunctionDecl *Fn = Step->Function.Function;
6180 DeclAccessPair FoundFn = Step->Function.FoundDecl;
6181 bool HadMultipleCandidates = Step->Function.HadMultipleCandidates;
6182 bool CreatedObject = false;
6183 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) {
6184 // Build a call to the selected constructor.
6185 SmallVector<Expr*, 8> ConstructorArgs;
6186 SourceLocation Loc = CurInit.get()->getLocStart();
6187 CurInit.get(); // Ownership transferred into MultiExprArg, below.
6189 // Determine the arguments required to actually perform the constructor
6191 Expr *Arg = CurInit.get();
6192 if (S.CompleteConstructorCall(Constructor,
6193 MultiExprArg(&Arg, 1),
6194 Loc, ConstructorArgs))
6197 // Build an expression that constructs a temporary.
6198 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor,
6200 HadMultipleCandidates,
6202 /*StdInitListInit*/ false,
6204 CXXConstructExpr::CK_Complete,
6206 if (CurInit.isInvalid())
6209 S.CheckConstructorAccess(Kind.getLocation(), Constructor, Entity,
6210 FoundFn.getAccess());
6211 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
6214 CastKind = CK_ConstructorConversion;
6215 QualType Class = S.Context.getTypeDeclType(Constructor->getParent());
6216 if (S.Context.hasSameUnqualifiedType(SourceType, Class) ||
6217 S.IsDerivedFrom(SourceType, Class))
6220 CreatedObject = true;
6222 // Build a call to the conversion function.
6223 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn);
6224 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), nullptr,
6226 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
6229 // FIXME: Should we move this initialization into a separate
6230 // derived-to-base conversion? I believe the answer is "no", because
6231 // we don't want to turn off access control here for c-style casts.
6232 ExprResult CurInitExprRes =
6233 S.PerformObjectArgumentInitialization(CurInit.get(),
6234 /*Qualifier=*/nullptr,
6235 FoundFn, Conversion);
6236 if(CurInitExprRes.isInvalid())
6238 CurInit = CurInitExprRes;
6240 // Build the actual call to the conversion function.
6241 CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion,
6242 HadMultipleCandidates);
6243 if (CurInit.isInvalid() || !CurInit.get())
6246 CastKind = CK_UserDefinedConversion;
6248 CreatedObject = Conversion->getReturnType()->isRecordType();
6251 bool RequiresCopy = !IsCopy && !isReferenceBinding(Steps.back());
6252 bool MaybeBindToTemp = RequiresCopy || shouldBindAsTemporary(Entity);
6254 if (!MaybeBindToTemp && CreatedObject && shouldDestroyTemporary(Entity)) {
6255 QualType T = CurInit.get()->getType();
6256 if (const RecordType *Record = T->getAs<RecordType>()) {
6257 CXXDestructorDecl *Destructor
6258 = S.LookupDestructor(cast<CXXRecordDecl>(Record->getDecl()));
6259 S.CheckDestructorAccess(CurInit.get()->getLocStart(), Destructor,
6260 S.PDiag(diag::err_access_dtor_temp) << T);
6261 S.MarkFunctionReferenced(CurInit.get()->getLocStart(), Destructor);
6262 if (S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getLocStart()))
6267 CurInit = ImplicitCastExpr::Create(S.Context, CurInit.get()->getType(),
6268 CastKind, CurInit.get(), nullptr,
6269 CurInit.get()->getValueKind());
6270 if (MaybeBindToTemp)
6271 CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
6273 CurInit = CopyObject(S, Entity.getType().getNonReferenceType(), Entity,
6274 CurInit, /*IsExtraneousCopy=*/false);
6278 case SK_QualificationConversionLValue:
6279 case SK_QualificationConversionXValue:
6280 case SK_QualificationConversionRValue: {
6281 // Perform a qualification conversion; these can never go wrong.
6283 Step->Kind == SK_QualificationConversionLValue ?
6285 (Step->Kind == SK_QualificationConversionXValue ?
6288 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type, CK_NoOp, VK);
6292 case SK_AtomicConversion: {
6293 assert(CurInit.get()->isRValue() && "cannot convert glvalue to atomic");
6294 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
6295 CK_NonAtomicToAtomic, VK_RValue);
6299 case SK_LValueToRValue: {
6300 assert(CurInit.get()->isGLValue() && "cannot load from a prvalue");
6301 CurInit = ImplicitCastExpr::Create(S.Context, Step->Type,
6302 CK_LValueToRValue, CurInit.get(),
6303 /*BasePath=*/nullptr, VK_RValue);
6307 case SK_ConversionSequence:
6308 case SK_ConversionSequenceNoNarrowing: {
6309 Sema::CheckedConversionKind CCK
6310 = Kind.isCStyleCast()? Sema::CCK_CStyleCast
6311 : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast
6312 : Kind.isExplicitCast()? Sema::CCK_OtherCast
6313 : Sema::CCK_ImplicitConversion;
6314 ExprResult CurInitExprRes =
6315 S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS,
6316 getAssignmentAction(Entity), CCK);
6317 if (CurInitExprRes.isInvalid())
6319 CurInit = CurInitExprRes;
6321 if (Step->Kind == SK_ConversionSequenceNoNarrowing &&
6322 S.getLangOpts().CPlusPlus && !CurInit.get()->isValueDependent())
6323 DiagnoseNarrowingInInitList(S, *Step->ICS, SourceType, Entity.getType(),
6328 case SK_ListInitialization: {
6329 InitListExpr *InitList = cast<InitListExpr>(CurInit.get());
6330 // If we're not initializing the top-level entity, we need to create an
6331 // InitializeTemporary entity for our target type.
6332 QualType Ty = Step->Type;
6333 bool IsTemporary = !S.Context.hasSameType(Entity.getType(), Ty);
6334 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty);
6335 InitializedEntity InitEntity = IsTemporary ? TempEntity : Entity;
6336 InitListChecker PerformInitList(S, InitEntity,
6337 InitList, Ty, /*VerifyOnly=*/false);
6338 if (PerformInitList.HadError())
6341 // Hack: We must update *ResultType if available in order to set the
6342 // bounds of arrays, e.g. in 'int ar[] = {1, 2, 3};'.
6343 // Worst case: 'const int (&arref)[] = {1, 2, 3};'.
6345 ResultType->getNonReferenceType()->isIncompleteArrayType()) {
6346 if ((*ResultType)->isRValueReferenceType())
6347 Ty = S.Context.getRValueReferenceType(Ty);
6348 else if ((*ResultType)->isLValueReferenceType())
6349 Ty = S.Context.getLValueReferenceType(Ty,
6350 (*ResultType)->getAs<LValueReferenceType>()->isSpelledAsLValue());
6354 InitListExpr *StructuredInitList =
6355 PerformInitList.getFullyStructuredList();
6357 CurInit = shouldBindAsTemporary(InitEntity)
6358 ? S.MaybeBindToTemporary(StructuredInitList)
6359 : StructuredInitList;
6363 case SK_ConstructorInitializationFromList: {
6364 // When an initializer list is passed for a parameter of type "reference
6365 // to object", we don't get an EK_Temporary entity, but instead an
6366 // EK_Parameter entity with reference type.
6367 // FIXME: This is a hack. What we really should do is create a user
6368 // conversion step for this case, but this makes it considerably more
6369 // complicated. For now, this will do.
6370 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
6371 Entity.getType().getNonReferenceType());
6372 bool UseTemporary = Entity.getType()->isReferenceType();
6373 assert(Args.size() == 1 && "expected a single argument for list init");
6374 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
6375 S.Diag(InitList->getExprLoc(), diag::warn_cxx98_compat_ctor_list_init)
6376 << InitList->getSourceRange();
6377 MultiExprArg Arg(InitList->getInits(), InitList->getNumInits());
6378 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity :
6381 ConstructorInitRequiresZeroInit,
6382 /*IsListInitialization*/true,
6383 /*IsStdInitListInit*/false,
6384 InitList->getLBraceLoc(),
6385 InitList->getRBraceLoc());
6389 case SK_UnwrapInitList:
6390 CurInit = cast<InitListExpr>(CurInit.get())->getInit(0);
6393 case SK_RewrapInitList: {
6394 Expr *E = CurInit.get();
6395 InitListExpr *Syntactic = Step->WrappingSyntacticList;
6396 InitListExpr *ILE = new (S.Context) InitListExpr(S.Context,
6397 Syntactic->getLBraceLoc(), E, Syntactic->getRBraceLoc());
6398 ILE->setSyntacticForm(Syntactic);
6399 ILE->setType(E->getType());
6400 ILE->setValueKind(E->getValueKind());
6405 case SK_ConstructorInitialization:
6406 case SK_StdInitializerListConstructorCall: {
6407 // When an initializer list is passed for a parameter of type "reference
6408 // to object", we don't get an EK_Temporary entity, but instead an
6409 // EK_Parameter entity with reference type.
6410 // FIXME: This is a hack. What we really should do is create a user
6411 // conversion step for this case, but this makes it considerably more
6412 // complicated. For now, this will do.
6413 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
6414 Entity.getType().getNonReferenceType());
6415 bool UseTemporary = Entity.getType()->isReferenceType();
6416 bool IsStdInitListInit =
6417 Step->Kind == SK_StdInitializerListConstructorCall;
6418 CurInit = PerformConstructorInitialization(
6419 S, UseTemporary ? TempEntity : Entity, Kind, Args, *Step,
6420 ConstructorInitRequiresZeroInit,
6421 /*IsListInitialization*/IsStdInitListInit,
6422 /*IsStdInitListInitialization*/IsStdInitListInit,
6423 /*LBraceLoc*/SourceLocation(),
6424 /*RBraceLoc*/SourceLocation());
6428 case SK_ZeroInitialization: {
6429 step_iterator NextStep = Step;
6431 if (NextStep != StepEnd &&
6432 (NextStep->Kind == SK_ConstructorInitialization ||
6433 NextStep->Kind == SK_ConstructorInitializationFromList)) {
6434 // The need for zero-initialization is recorded directly into
6435 // the call to the object's constructor within the next step.
6436 ConstructorInitRequiresZeroInit = true;
6437 } else if (Kind.getKind() == InitializationKind::IK_Value &&
6438 S.getLangOpts().CPlusPlus &&
6439 !Kind.isImplicitValueInit()) {
6440 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
6442 TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type,
6443 Kind.getRange().getBegin());
6445 CurInit = new (S.Context) CXXScalarValueInitExpr(
6446 TSInfo->getType().getNonLValueExprType(S.Context), TSInfo,
6447 Kind.getRange().getEnd());
6449 CurInit = new (S.Context) ImplicitValueInitExpr(Step->Type);
6454 case SK_CAssignment: {
6455 QualType SourceType = CurInit.get()->getType();
6456 ExprResult Result = CurInit;
6457 Sema::AssignConvertType ConvTy =
6458 S.CheckSingleAssignmentConstraints(Step->Type, Result, true,
6459 Entity.getKind() == InitializedEntity::EK_Parameter_CF_Audited);
6460 if (Result.isInvalid())
6464 // If this is a call, allow conversion to a transparent union.
6465 ExprResult CurInitExprRes = CurInit;
6466 if (ConvTy != Sema::Compatible &&
6467 Entity.isParameterKind() &&
6468 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes)
6469 == Sema::Compatible)
6470 ConvTy = Sema::Compatible;
6471 if (CurInitExprRes.isInvalid())
6473 CurInit = CurInitExprRes;
6476 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(),
6477 Step->Type, SourceType,
6479 getAssignmentAction(Entity, true),
6481 PrintInitLocationNote(S, Entity);
6483 } else if (Complained)
6484 PrintInitLocationNote(S, Entity);
6488 case SK_StringInit: {
6489 QualType Ty = Step->Type;
6490 CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty,
6491 S.Context.getAsArrayType(Ty), S);
6495 case SK_ObjCObjectConversion:
6496 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
6497 CK_ObjCObjectLValueCast,
6498 CurInit.get()->getValueKind());
6502 // Okay: we checked everything before creating this step. Note that
6503 // this is a GNU extension.
6504 S.Diag(Kind.getLocation(), diag::ext_array_init_copy)
6505 << Step->Type << CurInit.get()->getType()
6506 << CurInit.get()->getSourceRange();
6508 // If the destination type is an incomplete array type, update the
6509 // type accordingly.
6511 if (const IncompleteArrayType *IncompleteDest
6512 = S.Context.getAsIncompleteArrayType(Step->Type)) {
6513 if (const ConstantArrayType *ConstantSource
6514 = S.Context.getAsConstantArrayType(CurInit.get()->getType())) {
6515 *ResultType = S.Context.getConstantArrayType(
6516 IncompleteDest->getElementType(),
6517 ConstantSource->getSize(),
6518 ArrayType::Normal, 0);
6524 case SK_ParenthesizedArrayInit:
6525 // Okay: we checked everything before creating this step. Note that
6526 // this is a GNU extension.
6527 S.Diag(Kind.getLocation(), diag::ext_array_init_parens)
6528 << CurInit.get()->getSourceRange();
6531 case SK_PassByIndirectCopyRestore:
6532 case SK_PassByIndirectRestore:
6533 checkIndirectCopyRestoreSource(S, CurInit.get());
6534 CurInit = new (S.Context) ObjCIndirectCopyRestoreExpr(
6535 CurInit.get(), Step->Type,
6536 Step->Kind == SK_PassByIndirectCopyRestore);
6539 case SK_ProduceObjCObject:
6541 ImplicitCastExpr::Create(S.Context, Step->Type, CK_ARCProduceObject,
6542 CurInit.get(), nullptr, VK_RValue);
6545 case SK_StdInitializerList: {
6546 S.Diag(CurInit.get()->getExprLoc(),
6547 diag::warn_cxx98_compat_initializer_list_init)
6548 << CurInit.get()->getSourceRange();
6550 // Materialize the temporary into memory.
6551 MaterializeTemporaryExpr *MTE = new (S.Context)
6552 MaterializeTemporaryExpr(CurInit.get()->getType(), CurInit.get(),
6553 /*BoundToLvalueReference=*/false);
6555 // Maybe lifetime-extend the array temporary's subobjects to match the
6556 // entity's lifetime.
6557 if (const InitializedEntity *ExtendingEntity =
6558 getEntityForTemporaryLifetimeExtension(&Entity))
6559 if (performReferenceExtension(MTE, ExtendingEntity))
6560 warnOnLifetimeExtension(S, Entity, CurInit.get(),
6561 /*IsInitializerList=*/true,
6562 ExtendingEntity->getDecl());
6564 // Wrap it in a construction of a std::initializer_list<T>.
6565 CurInit = new (S.Context) CXXStdInitializerListExpr(Step->Type, MTE);
6567 // Bind the result, in case the library has given initializer_list a
6568 // non-trivial destructor.
6569 if (shouldBindAsTemporary(Entity))
6570 CurInit = S.MaybeBindToTemporary(CurInit.get());
6574 case SK_OCLSamplerInit: {
6575 assert(Step->Type->isSamplerT() &&
6576 "Sampler initialization on non-sampler type.");
6578 QualType SourceType = CurInit.get()->getType();
6580 if (Entity.isParameterKind()) {
6581 if (!SourceType->isSamplerT())
6582 S.Diag(Kind.getLocation(), diag::err_sampler_argument_required)
6584 } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
6585 llvm_unreachable("Invalid EntityKind!");
6590 case SK_OCLZeroEvent: {
6591 assert(Step->Type->isEventT() &&
6592 "Event initialization on non-event type.");
6594 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
6596 CurInit.get()->getValueKind());
6602 // Diagnose non-fatal problems with the completed initialization.
6603 if (Entity.getKind() == InitializedEntity::EK_Member &&
6604 cast<FieldDecl>(Entity.getDecl())->isBitField())
6605 S.CheckBitFieldInitialization(Kind.getLocation(),
6606 cast<FieldDecl>(Entity.getDecl()),
6609 // Check for std::move on construction.
6610 if (const Expr *E = CurInit.get()) {
6611 CheckMoveOnConstruction(S, E,
6612 Entity.getKind() == InitializedEntity::EK_Result);
6618 /// Somewhere within T there is an uninitialized reference subobject.
6619 /// Dig it out and diagnose it.
6620 static bool DiagnoseUninitializedReference(Sema &S, SourceLocation Loc,
6622 if (T->isReferenceType()) {
6623 S.Diag(Loc, diag::err_reference_without_init)
6624 << T.getNonReferenceType();
6628 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
6629 if (!RD || !RD->hasUninitializedReferenceMember())
6632 for (const auto *FI : RD->fields()) {
6633 if (FI->isUnnamedBitfield())
6636 if (DiagnoseUninitializedReference(S, FI->getLocation(), FI->getType())) {
6637 S.Diag(Loc, diag::note_value_initialization_here) << RD;
6642 for (const auto &BI : RD->bases()) {
6643 if (DiagnoseUninitializedReference(S, BI.getLocStart(), BI.getType())) {
6644 S.Diag(Loc, diag::note_value_initialization_here) << RD;
6653 //===----------------------------------------------------------------------===//
6654 // Diagnose initialization failures
6655 //===----------------------------------------------------------------------===//
6657 /// Emit notes associated with an initialization that failed due to a
6658 /// "simple" conversion failure.
6659 static void emitBadConversionNotes(Sema &S, const InitializedEntity &entity,
6661 QualType destType = entity.getType();
6662 if (destType.getNonReferenceType()->isObjCObjectPointerType() &&
6663 op->getType()->isObjCObjectPointerType()) {
6665 // Emit a possible note about the conversion failing because the
6666 // operand is a message send with a related result type.
6667 S.EmitRelatedResultTypeNote(op);
6669 // Emit a possible note about a return failing because we're
6670 // expecting a related result type.
6671 if (entity.getKind() == InitializedEntity::EK_Result)
6672 S.EmitRelatedResultTypeNoteForReturn(destType);
6676 static void diagnoseListInit(Sema &S, const InitializedEntity &Entity,
6677 InitListExpr *InitList) {
6678 QualType DestType = Entity.getType();
6681 if (S.getLangOpts().CPlusPlus11 && S.isStdInitializerList(DestType, &E)) {
6682 QualType ArrayType = S.Context.getConstantArrayType(
6684 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
6685 InitList->getNumInits()),
6686 clang::ArrayType::Normal, 0);
6687 InitializedEntity HiddenArray =
6688 InitializedEntity::InitializeTemporary(ArrayType);
6689 return diagnoseListInit(S, HiddenArray, InitList);
6692 if (DestType->isReferenceType()) {
6693 // A list-initialization failure for a reference means that we tried to
6694 // create a temporary of the inner type (per [dcl.init.list]p3.6) and the
6695 // inner initialization failed.
6696 QualType T = DestType->getAs<ReferenceType>()->getPointeeType();
6697 diagnoseListInit(S, InitializedEntity::InitializeTemporary(T), InitList);
6698 SourceLocation Loc = InitList->getLocStart();
6699 if (auto *D = Entity.getDecl())
6700 Loc = D->getLocation();
6701 S.Diag(Loc, diag::note_in_reference_temporary_list_initializer) << T;
6705 InitListChecker DiagnoseInitList(S, Entity, InitList, DestType,
6706 /*VerifyOnly=*/false);
6707 assert(DiagnoseInitList.HadError() &&
6708 "Inconsistent init list check result.");
6711 bool InitializationSequence::Diagnose(Sema &S,
6712 const InitializedEntity &Entity,
6713 const InitializationKind &Kind,
6714 ArrayRef<Expr *> Args) {
6718 QualType DestType = Entity.getType();
6720 case FK_TooManyInitsForReference:
6721 // FIXME: Customize for the initialized entity?
6723 // Dig out the reference subobject which is uninitialized and diagnose it.
6724 // If this is value-initialization, this could be nested some way within
6726 assert(Kind.getKind() == InitializationKind::IK_Value ||
6727 DestType->isReferenceType());
6729 DiagnoseUninitializedReference(S, Kind.getLocation(), DestType);
6730 assert(Diagnosed && "couldn't find uninitialized reference to diagnose");
6732 } else // FIXME: diagnostic below could be better!
6733 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits)
6734 << SourceRange(Args.front()->getLocStart(), Args.back()->getLocEnd());
6737 case FK_ArrayNeedsInitList:
6738 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 0;
6740 case FK_ArrayNeedsInitListOrStringLiteral:
6741 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 1;
6743 case FK_ArrayNeedsInitListOrWideStringLiteral:
6744 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 2;
6746 case FK_NarrowStringIntoWideCharArray:
6747 S.Diag(Kind.getLocation(), diag::err_array_init_narrow_string_into_wchar);
6749 case FK_WideStringIntoCharArray:
6750 S.Diag(Kind.getLocation(), diag::err_array_init_wide_string_into_char);
6752 case FK_IncompatWideStringIntoWideChar:
6753 S.Diag(Kind.getLocation(),
6754 diag::err_array_init_incompat_wide_string_into_wchar);
6756 case FK_ArrayTypeMismatch:
6757 case FK_NonConstantArrayInit:
6758 S.Diag(Kind.getLocation(),
6759 (Failure == FK_ArrayTypeMismatch
6760 ? diag::err_array_init_different_type
6761 : diag::err_array_init_non_constant_array))
6762 << DestType.getNonReferenceType()
6763 << Args[0]->getType()
6764 << Args[0]->getSourceRange();
6767 case FK_VariableLengthArrayHasInitializer:
6768 S.Diag(Kind.getLocation(), diag::err_variable_object_no_init)
6769 << Args[0]->getSourceRange();
6772 case FK_AddressOfOverloadFailed: {
6773 DeclAccessPair Found;
6774 S.ResolveAddressOfOverloadedFunction(Args[0],
6775 DestType.getNonReferenceType(),
6781 case FK_ReferenceInitOverloadFailed:
6782 case FK_UserConversionOverloadFailed:
6783 switch (FailedOverloadResult) {
6785 if (Failure == FK_UserConversionOverloadFailed)
6786 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition)
6787 << Args[0]->getType() << DestType
6788 << Args[0]->getSourceRange();
6790 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous)
6791 << DestType << Args[0]->getType()
6792 << Args[0]->getSourceRange();
6794 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args);
6797 case OR_No_Viable_Function:
6798 if (!S.RequireCompleteType(Kind.getLocation(),
6799 DestType.getNonReferenceType(),
6800 diag::err_typecheck_nonviable_condition_incomplete,
6801 Args[0]->getType(), Args[0]->getSourceRange()))
6802 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition)
6803 << Args[0]->getType() << Args[0]->getSourceRange()
6804 << DestType.getNonReferenceType();
6806 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args);
6810 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function)
6811 << Args[0]->getType() << DestType.getNonReferenceType()
6812 << Args[0]->getSourceRange();
6813 OverloadCandidateSet::iterator Best;
6814 OverloadingResult Ovl
6815 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best,
6817 if (Ovl == OR_Deleted) {
6818 S.NoteDeletedFunction(Best->Function);
6820 llvm_unreachable("Inconsistent overload resolution?");
6826 llvm_unreachable("Conversion did not fail!");
6830 case FK_NonConstLValueReferenceBindingToTemporary:
6831 if (isa<InitListExpr>(Args[0])) {
6832 S.Diag(Kind.getLocation(),
6833 diag::err_lvalue_reference_bind_to_initlist)
6834 << DestType.getNonReferenceType().isVolatileQualified()
6835 << DestType.getNonReferenceType()
6836 << Args[0]->getSourceRange();
6839 // Intentional fallthrough
6841 case FK_NonConstLValueReferenceBindingToUnrelated:
6842 S.Diag(Kind.getLocation(),
6843 Failure == FK_NonConstLValueReferenceBindingToTemporary
6844 ? diag::err_lvalue_reference_bind_to_temporary
6845 : diag::err_lvalue_reference_bind_to_unrelated)
6846 << DestType.getNonReferenceType().isVolatileQualified()
6847 << DestType.getNonReferenceType()
6848 << Args[0]->getType()
6849 << Args[0]->getSourceRange();
6852 case FK_RValueReferenceBindingToLValue:
6853 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref)
6854 << DestType.getNonReferenceType() << Args[0]->getType()
6855 << Args[0]->getSourceRange();
6858 case FK_ReferenceInitDropsQualifiers: {
6859 QualType SourceType = Args[0]->getType();
6860 QualType NonRefType = DestType.getNonReferenceType();
6861 Qualifiers DroppedQualifiers =
6862 SourceType.getQualifiers() - NonRefType.getQualifiers();
6864 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals)
6867 << DroppedQualifiers.getCVRQualifiers()
6868 << Args[0]->getSourceRange();
6872 case FK_ReferenceInitFailed:
6873 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed)
6874 << DestType.getNonReferenceType()
6875 << Args[0]->isLValue()
6876 << Args[0]->getType()
6877 << Args[0]->getSourceRange();
6878 emitBadConversionNotes(S, Entity, Args[0]);
6881 case FK_ConversionFailed: {
6882 QualType FromType = Args[0]->getType();
6883 PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed)
6884 << (int)Entity.getKind()
6886 << Args[0]->isLValue()
6888 << Args[0]->getSourceRange();
6889 S.HandleFunctionTypeMismatch(PDiag, FromType, DestType);
6890 S.Diag(Kind.getLocation(), PDiag);
6891 emitBadConversionNotes(S, Entity, Args[0]);
6895 case FK_ConversionFromPropertyFailed:
6896 // No-op. This error has already been reported.
6899 case FK_TooManyInitsForScalar: {
6902 auto *InitList = dyn_cast<InitListExpr>(Args[0]);
6903 if (InitList && InitList->getNumInits() == 1)
6904 R = SourceRange(InitList->getInit(0)->getLocEnd(), InitList->getLocEnd());
6906 R = SourceRange(Args.front()->getLocEnd(), Args.back()->getLocEnd());
6908 R.setBegin(S.getLocForEndOfToken(R.getBegin()));
6909 if (Kind.isCStyleOrFunctionalCast())
6910 S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg)
6913 S.Diag(Kind.getLocation(), diag::err_excess_initializers)
6914 << /*scalar=*/2 << R;
6918 case FK_ReferenceBindingToInitList:
6919 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list)
6920 << DestType.getNonReferenceType() << Args[0]->getSourceRange();
6923 case FK_InitListBadDestinationType:
6924 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type)
6925 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange();
6928 case FK_ListConstructorOverloadFailed:
6929 case FK_ConstructorOverloadFailed: {
6930 SourceRange ArgsRange;
6932 ArgsRange = SourceRange(Args.front()->getLocStart(),
6933 Args.back()->getLocEnd());
6935 if (Failure == FK_ListConstructorOverloadFailed) {
6936 assert(Args.size() == 1 &&
6937 "List construction from other than 1 argument.");
6938 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
6939 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
6942 // FIXME: Using "DestType" for the entity we're printing is probably
6944 switch (FailedOverloadResult) {
6946 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init)
6947 << DestType << ArgsRange;
6948 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args);
6951 case OR_No_Viable_Function:
6952 if (Kind.getKind() == InitializationKind::IK_Default &&
6953 (Entity.getKind() == InitializedEntity::EK_Base ||
6954 Entity.getKind() == InitializedEntity::EK_Member) &&
6955 isa<CXXConstructorDecl>(S.CurContext)) {
6956 // This is implicit default initialization of a member or
6957 // base within a constructor. If no viable function was
6958 // found, notify the user that she needs to explicitly
6959 // initialize this base/member.
6960 CXXConstructorDecl *Constructor
6961 = cast<CXXConstructorDecl>(S.CurContext);
6962 if (Entity.getKind() == InitializedEntity::EK_Base) {
6963 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
6964 << (Constructor->getInheritedConstructor() ? 2 :
6965 Constructor->isImplicit() ? 1 : 0)
6966 << S.Context.getTypeDeclType(Constructor->getParent())
6968 << Entity.getType();
6970 RecordDecl *BaseDecl
6971 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>()
6973 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl)
6974 << S.Context.getTagDeclType(BaseDecl);
6976 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
6977 << (Constructor->getInheritedConstructor() ? 2 :
6978 Constructor->isImplicit() ? 1 : 0)
6979 << S.Context.getTypeDeclType(Constructor->getParent())
6981 << Entity.getName();
6982 S.Diag(Entity.getDecl()->getLocation(),
6983 diag::note_member_declared_at);
6985 if (const RecordType *Record
6986 = Entity.getType()->getAs<RecordType>())
6987 S.Diag(Record->getDecl()->getLocation(),
6988 diag::note_previous_decl)
6989 << S.Context.getTagDeclType(Record->getDecl());
6994 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init)
6995 << DestType << ArgsRange;
6996 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args);
7000 OverloadCandidateSet::iterator Best;
7001 OverloadingResult Ovl
7002 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
7003 if (Ovl != OR_Deleted) {
7004 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
7005 << true << DestType << ArgsRange;
7006 llvm_unreachable("Inconsistent overload resolution?");
7010 // If this is a defaulted or implicitly-declared function, then
7011 // it was implicitly deleted. Make it clear that the deletion was
7013 if (S.isImplicitlyDeleted(Best->Function))
7014 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init)
7015 << S.getSpecialMember(cast<CXXMethodDecl>(Best->Function))
7016 << DestType << ArgsRange;
7018 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
7019 << true << DestType << ArgsRange;
7021 S.NoteDeletedFunction(Best->Function);
7026 llvm_unreachable("Conversion did not fail!");
7031 case FK_DefaultInitOfConst:
7032 if (Entity.getKind() == InitializedEntity::EK_Member &&
7033 isa<CXXConstructorDecl>(S.CurContext)) {
7034 // This is implicit default-initialization of a const member in
7035 // a constructor. Complain that it needs to be explicitly
7037 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext);
7038 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor)
7039 << (Constructor->getInheritedConstructor() ? 2 :
7040 Constructor->isImplicit() ? 1 : 0)
7041 << S.Context.getTypeDeclType(Constructor->getParent())
7043 << Entity.getName();
7044 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl)
7045 << Entity.getName();
7047 S.Diag(Kind.getLocation(), diag::err_default_init_const)
7048 << DestType << (bool)DestType->getAs<RecordType>();
7053 S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType,
7054 diag::err_init_incomplete_type);
7057 case FK_ListInitializationFailed: {
7058 // Run the init list checker again to emit diagnostics.
7059 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
7060 diagnoseListInit(S, Entity, InitList);
7064 case FK_PlaceholderType: {
7065 // FIXME: Already diagnosed!
7069 case FK_ExplicitConstructor: {
7070 S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor)
7071 << Args[0]->getSourceRange();
7072 OverloadCandidateSet::iterator Best;
7073 OverloadingResult Ovl
7074 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
7076 assert(Ovl == OR_Success && "Inconsistent overload resolution");
7077 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
7078 S.Diag(CtorDecl->getLocation(), diag::note_constructor_declared_here);
7083 PrintInitLocationNote(S, Entity);
7087 void InitializationSequence::dump(raw_ostream &OS) const {
7088 switch (SequenceKind) {
7089 case FailedSequence: {
7090 OS << "Failed sequence: ";
7092 case FK_TooManyInitsForReference:
7093 OS << "too many initializers for reference";
7096 case FK_ArrayNeedsInitList:
7097 OS << "array requires initializer list";
7100 case FK_ArrayNeedsInitListOrStringLiteral:
7101 OS << "array requires initializer list or string literal";
7104 case FK_ArrayNeedsInitListOrWideStringLiteral:
7105 OS << "array requires initializer list or wide string literal";
7108 case FK_NarrowStringIntoWideCharArray:
7109 OS << "narrow string into wide char array";
7112 case FK_WideStringIntoCharArray:
7113 OS << "wide string into char array";
7116 case FK_IncompatWideStringIntoWideChar:
7117 OS << "incompatible wide string into wide char array";
7120 case FK_ArrayTypeMismatch:
7121 OS << "array type mismatch";
7124 case FK_NonConstantArrayInit:
7125 OS << "non-constant array initializer";
7128 case FK_AddressOfOverloadFailed:
7129 OS << "address of overloaded function failed";
7132 case FK_ReferenceInitOverloadFailed:
7133 OS << "overload resolution for reference initialization failed";
7136 case FK_NonConstLValueReferenceBindingToTemporary:
7137 OS << "non-const lvalue reference bound to temporary";
7140 case FK_NonConstLValueReferenceBindingToUnrelated:
7141 OS << "non-const lvalue reference bound to unrelated type";
7144 case FK_RValueReferenceBindingToLValue:
7145 OS << "rvalue reference bound to an lvalue";
7148 case FK_ReferenceInitDropsQualifiers:
7149 OS << "reference initialization drops qualifiers";
7152 case FK_ReferenceInitFailed:
7153 OS << "reference initialization failed";
7156 case FK_ConversionFailed:
7157 OS << "conversion failed";
7160 case FK_ConversionFromPropertyFailed:
7161 OS << "conversion from property failed";
7164 case FK_TooManyInitsForScalar:
7165 OS << "too many initializers for scalar";
7168 case FK_ReferenceBindingToInitList:
7169 OS << "referencing binding to initializer list";
7172 case FK_InitListBadDestinationType:
7173 OS << "initializer list for non-aggregate, non-scalar type";
7176 case FK_UserConversionOverloadFailed:
7177 OS << "overloading failed for user-defined conversion";
7180 case FK_ConstructorOverloadFailed:
7181 OS << "constructor overloading failed";
7184 case FK_DefaultInitOfConst:
7185 OS << "default initialization of a const variable";
7189 OS << "initialization of incomplete type";
7192 case FK_ListInitializationFailed:
7193 OS << "list initialization checker failure";
7196 case FK_VariableLengthArrayHasInitializer:
7197 OS << "variable length array has an initializer";
7200 case FK_PlaceholderType:
7201 OS << "initializer expression isn't contextually valid";
7204 case FK_ListConstructorOverloadFailed:
7205 OS << "list constructor overloading failed";
7208 case FK_ExplicitConstructor:
7209 OS << "list copy initialization chose explicit constructor";
7216 case DependentSequence:
7217 OS << "Dependent sequence\n";
7220 case NormalSequence:
7221 OS << "Normal sequence: ";
7225 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) {
7226 if (S != step_begin()) {
7231 case SK_ResolveAddressOfOverloadedFunction:
7232 OS << "resolve address of overloaded function";
7235 case SK_CastDerivedToBaseRValue:
7236 OS << "derived-to-base case (rvalue" << S->Type.getAsString() << ")";
7239 case SK_CastDerivedToBaseXValue:
7240 OS << "derived-to-base case (xvalue" << S->Type.getAsString() << ")";
7243 case SK_CastDerivedToBaseLValue:
7244 OS << "derived-to-base case (lvalue" << S->Type.getAsString() << ")";
7247 case SK_BindReference:
7248 OS << "bind reference to lvalue";
7251 case SK_BindReferenceToTemporary:
7252 OS << "bind reference to a temporary";
7255 case SK_ExtraneousCopyToTemporary:
7256 OS << "extraneous C++03 copy to temporary";
7259 case SK_UserConversion:
7260 OS << "user-defined conversion via " << *S->Function.Function;
7263 case SK_QualificationConversionRValue:
7264 OS << "qualification conversion (rvalue)";
7267 case SK_QualificationConversionXValue:
7268 OS << "qualification conversion (xvalue)";
7271 case SK_QualificationConversionLValue:
7272 OS << "qualification conversion (lvalue)";
7275 case SK_AtomicConversion:
7276 OS << "non-atomic-to-atomic conversion";
7279 case SK_LValueToRValue:
7280 OS << "load (lvalue to rvalue)";
7283 case SK_ConversionSequence:
7284 OS << "implicit conversion sequence (";
7285 S->ICS->dump(); // FIXME: use OS
7289 case SK_ConversionSequenceNoNarrowing:
7290 OS << "implicit conversion sequence with narrowing prohibited (";
7291 S->ICS->dump(); // FIXME: use OS
7295 case SK_ListInitialization:
7296 OS << "list aggregate initialization";
7299 case SK_UnwrapInitList:
7300 OS << "unwrap reference initializer list";
7303 case SK_RewrapInitList:
7304 OS << "rewrap reference initializer list";
7307 case SK_ConstructorInitialization:
7308 OS << "constructor initialization";
7311 case SK_ConstructorInitializationFromList:
7312 OS << "list initialization via constructor";
7315 case SK_ZeroInitialization:
7316 OS << "zero initialization";
7319 case SK_CAssignment:
7320 OS << "C assignment";
7324 OS << "string initialization";
7327 case SK_ObjCObjectConversion:
7328 OS << "Objective-C object conversion";
7332 OS << "array initialization";
7335 case SK_ParenthesizedArrayInit:
7336 OS << "parenthesized array initialization";
7339 case SK_PassByIndirectCopyRestore:
7340 OS << "pass by indirect copy and restore";
7343 case SK_PassByIndirectRestore:
7344 OS << "pass by indirect restore";
7347 case SK_ProduceObjCObject:
7348 OS << "Objective-C object retension";
7351 case SK_StdInitializerList:
7352 OS << "std::initializer_list from initializer list";
7355 case SK_StdInitializerListConstructorCall:
7356 OS << "list initialization from std::initializer_list";
7359 case SK_OCLSamplerInit:
7360 OS << "OpenCL sampler_t from integer constant";
7363 case SK_OCLZeroEvent:
7364 OS << "OpenCL event_t from zero";
7368 OS << " [" << S->Type.getAsString() << ']';
7374 void InitializationSequence::dump() const {
7378 static void DiagnoseNarrowingInInitList(Sema &S,
7379 const ImplicitConversionSequence &ICS,
7380 QualType PreNarrowingType,
7381 QualType EntityType,
7382 const Expr *PostInit) {
7383 const StandardConversionSequence *SCS = nullptr;
7384 switch (ICS.getKind()) {
7385 case ImplicitConversionSequence::StandardConversion:
7386 SCS = &ICS.Standard;
7388 case ImplicitConversionSequence::UserDefinedConversion:
7389 SCS = &ICS.UserDefined.After;
7391 case ImplicitConversionSequence::AmbiguousConversion:
7392 case ImplicitConversionSequence::EllipsisConversion:
7393 case ImplicitConversionSequence::BadConversion:
7397 // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion.
7398 APValue ConstantValue;
7399 QualType ConstantType;
7400 switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue,
7402 case NK_Not_Narrowing:
7403 // No narrowing occurred.
7406 case NK_Type_Narrowing:
7407 // This was a floating-to-integer conversion, which is always considered a
7408 // narrowing conversion even if the value is a constant and can be
7409 // represented exactly as an integer.
7410 S.Diag(PostInit->getLocStart(),
7411 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
7412 ? diag::warn_init_list_type_narrowing
7413 : diag::ext_init_list_type_narrowing)
7414 << PostInit->getSourceRange()
7415 << PreNarrowingType.getLocalUnqualifiedType()
7416 << EntityType.getLocalUnqualifiedType();
7419 case NK_Constant_Narrowing:
7420 // A constant value was narrowed.
7421 S.Diag(PostInit->getLocStart(),
7422 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
7423 ? diag::warn_init_list_constant_narrowing
7424 : diag::ext_init_list_constant_narrowing)
7425 << PostInit->getSourceRange()
7426 << ConstantValue.getAsString(S.getASTContext(), ConstantType)
7427 << EntityType.getLocalUnqualifiedType();
7430 case NK_Variable_Narrowing:
7431 // A variable's value may have been narrowed.
7432 S.Diag(PostInit->getLocStart(),
7433 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
7434 ? diag::warn_init_list_variable_narrowing
7435 : diag::ext_init_list_variable_narrowing)
7436 << PostInit->getSourceRange()
7437 << PreNarrowingType.getLocalUnqualifiedType()
7438 << EntityType.getLocalUnqualifiedType();
7442 SmallString<128> StaticCast;
7443 llvm::raw_svector_ostream OS(StaticCast);
7444 OS << "static_cast<";
7445 if (const TypedefType *TT = EntityType->getAs<TypedefType>()) {
7446 // It's important to use the typedef's name if there is one so that the
7447 // fixit doesn't break code using types like int64_t.
7449 // FIXME: This will break if the typedef requires qualification. But
7450 // getQualifiedNameAsString() includes non-machine-parsable components.
7451 OS << *TT->getDecl();
7452 } else if (const BuiltinType *BT = EntityType->getAs<BuiltinType>())
7453 OS << BT->getName(S.getLangOpts());
7455 // Oops, we didn't find the actual type of the variable. Don't emit a fixit
7456 // with a broken cast.
7460 S.Diag(PostInit->getLocStart(), diag::note_init_list_narrowing_silence)
7461 << PostInit->getSourceRange()
7462 << FixItHint::CreateInsertion(PostInit->getLocStart(), OS.str())
7463 << FixItHint::CreateInsertion(
7464 S.getLocForEndOfToken(PostInit->getLocEnd()), ")");
7467 //===----------------------------------------------------------------------===//
7468 // Initialization helper functions
7469 //===----------------------------------------------------------------------===//
7471 Sema::CanPerformCopyInitialization(const InitializedEntity &Entity,
7473 if (Init.isInvalid())
7476 Expr *InitE = Init.get();
7477 assert(InitE && "No initialization expression");
7479 InitializationKind Kind
7480 = InitializationKind::CreateCopy(InitE->getLocStart(), SourceLocation());
7481 InitializationSequence Seq(*this, Entity, Kind, InitE);
7482 return !Seq.Failed();
7486 Sema::PerformCopyInitialization(const InitializedEntity &Entity,
7487 SourceLocation EqualLoc,
7489 bool TopLevelOfInitList,
7490 bool AllowExplicit) {
7491 if (Init.isInvalid())
7494 Expr *InitE = Init.get();
7495 assert(InitE && "No initialization expression?");
7497 if (EqualLoc.isInvalid())
7498 EqualLoc = InitE->getLocStart();
7500 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(),
7503 InitializationSequence Seq(*this, Entity, Kind, InitE, TopLevelOfInitList);
7505 ExprResult Result = Seq.Perform(*this, Entity, Kind, InitE);