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/AST/ASTContext.h"
15 #include "clang/AST/DeclObjC.h"
16 #include "clang/AST/ExprCXX.h"
17 #include "clang/AST/ExprObjC.h"
18 #include "clang/AST/TypeLoc.h"
19 #include "clang/Basic/TargetInfo.h"
20 #include "clang/Sema/Designator.h"
21 #include "clang/Sema/Initialization.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 //===----------------------------------------------------------------------===//
209 /// @brief Semantic checking for initializer lists.
211 /// The InitListChecker class contains a set of routines that each
212 /// handle the initialization of a certain kind of entity, e.g.,
213 /// arrays, vectors, struct/union types, scalars, etc. The
214 /// InitListChecker itself performs a recursive walk of the subobject
215 /// structure of the type to be initialized, while stepping through
216 /// the initializer list one element at a time. The IList and Index
217 /// parameters to each of the Check* routines contain the active
218 /// (syntactic) initializer list and the index into that initializer
219 /// list that represents the current initializer. Each routine is
220 /// responsible for moving that Index forward as it consumes elements.
222 /// Each Check* routine also has a StructuredList/StructuredIndex
223 /// arguments, which contains the current "structured" (semantic)
224 /// initializer list and the index into that initializer list where we
225 /// are copying initializers as we map them over to the semantic
226 /// list. Once we have completed our recursive walk of the subobject
227 /// structure, we will have constructed a full semantic initializer
230 /// C99 designators cause changes in the initializer list traversal,
231 /// because they make the initialization "jump" into a specific
232 /// subobject and then continue the initialization from that
233 /// point. CheckDesignatedInitializer() recursively steps into the
234 /// designated subobject and manages backing out the recursion to
235 /// initialize the subobjects after the one designated.
236 class InitListChecker {
239 bool VerifyOnly; // no diagnostics, no structure building
240 bool TreatUnavailableAsInvalid; // Used only in VerifyOnly mode.
241 llvm::DenseMap<InitListExpr *, InitListExpr *> SyntacticToSemantic;
242 InitListExpr *FullyStructuredList;
244 void CheckImplicitInitList(const InitializedEntity &Entity,
245 InitListExpr *ParentIList, QualType T,
246 unsigned &Index, InitListExpr *StructuredList,
247 unsigned &StructuredIndex);
248 void CheckExplicitInitList(const InitializedEntity &Entity,
249 InitListExpr *IList, QualType &T,
250 InitListExpr *StructuredList,
251 bool TopLevelObject = false);
252 void CheckListElementTypes(const InitializedEntity &Entity,
253 InitListExpr *IList, QualType &DeclType,
254 bool SubobjectIsDesignatorContext,
256 InitListExpr *StructuredList,
257 unsigned &StructuredIndex,
258 bool TopLevelObject = false);
259 void CheckSubElementType(const InitializedEntity &Entity,
260 InitListExpr *IList, QualType ElemType,
262 InitListExpr *StructuredList,
263 unsigned &StructuredIndex);
264 void CheckComplexType(const InitializedEntity &Entity,
265 InitListExpr *IList, QualType DeclType,
267 InitListExpr *StructuredList,
268 unsigned &StructuredIndex);
269 void CheckScalarType(const InitializedEntity &Entity,
270 InitListExpr *IList, QualType DeclType,
272 InitListExpr *StructuredList,
273 unsigned &StructuredIndex);
274 void CheckReferenceType(const InitializedEntity &Entity,
275 InitListExpr *IList, QualType DeclType,
277 InitListExpr *StructuredList,
278 unsigned &StructuredIndex);
279 void CheckVectorType(const InitializedEntity &Entity,
280 InitListExpr *IList, QualType DeclType, unsigned &Index,
281 InitListExpr *StructuredList,
282 unsigned &StructuredIndex);
283 void CheckStructUnionTypes(const InitializedEntity &Entity,
284 InitListExpr *IList, QualType DeclType,
285 CXXRecordDecl::base_class_range Bases,
286 RecordDecl::field_iterator Field,
287 bool SubobjectIsDesignatorContext, unsigned &Index,
288 InitListExpr *StructuredList,
289 unsigned &StructuredIndex,
290 bool TopLevelObject = false);
291 void CheckArrayType(const InitializedEntity &Entity,
292 InitListExpr *IList, QualType &DeclType,
293 llvm::APSInt elementIndex,
294 bool SubobjectIsDesignatorContext, unsigned &Index,
295 InitListExpr *StructuredList,
296 unsigned &StructuredIndex);
297 bool CheckDesignatedInitializer(const InitializedEntity &Entity,
298 InitListExpr *IList, DesignatedInitExpr *DIE,
300 QualType &CurrentObjectType,
301 RecordDecl::field_iterator *NextField,
302 llvm::APSInt *NextElementIndex,
304 InitListExpr *StructuredList,
305 unsigned &StructuredIndex,
306 bool FinishSubobjectInit,
307 bool TopLevelObject);
308 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
309 QualType CurrentObjectType,
310 InitListExpr *StructuredList,
311 unsigned StructuredIndex,
312 SourceRange InitRange,
313 bool IsFullyOverwritten = false);
314 void UpdateStructuredListElement(InitListExpr *StructuredList,
315 unsigned &StructuredIndex,
317 int numArrayElements(QualType DeclType);
318 int numStructUnionElements(QualType DeclType);
320 static ExprResult PerformEmptyInit(Sema &SemaRef,
322 const InitializedEntity &Entity,
324 bool TreatUnavailableAsInvalid);
326 // Explanation on the "FillWithNoInit" mode:
328 // Assume we have the following definitions (Case#1):
329 // struct P { char x[6][6]; } xp = { .x[1] = "bar" };
330 // struct PP { struct P lp; } l = { .lp = xp, .lp.x[1][2] = 'f' };
332 // l.lp.x[1][0..1] should not be filled with implicit initializers because the
333 // "base" initializer "xp" will provide values for them; l.lp.x[1] will be "baf".
335 // But if we have (Case#2):
336 // struct PP l = { .lp = xp, .lp.x[1] = { [2] = 'f' } };
338 // l.lp.x[1][0..1] are implicitly initialized and do not use values from the
339 // "base" initializer; l.lp.x[1] will be "\0\0f\0\0\0".
341 // To distinguish Case#1 from Case#2, and also to avoid leaving many "holes"
342 // in the InitListExpr, the "holes" in Case#1 are filled not with empty
343 // initializers but with special "NoInitExpr" place holders, which tells the
344 // CodeGen not to generate any initializers for these parts.
345 void FillInEmptyInitForBase(unsigned Init, const CXXBaseSpecifier &Base,
346 const InitializedEntity &ParentEntity,
347 InitListExpr *ILE, bool &RequiresSecondPass,
348 bool FillWithNoInit);
349 void FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
350 const InitializedEntity &ParentEntity,
351 InitListExpr *ILE, bool &RequiresSecondPass,
352 bool FillWithNoInit = false);
353 void FillInEmptyInitializations(const InitializedEntity &Entity,
354 InitListExpr *ILE, bool &RequiresSecondPass,
355 bool FillWithNoInit = false);
356 bool CheckFlexibleArrayInit(const InitializedEntity &Entity,
357 Expr *InitExpr, FieldDecl *Field,
358 bool TopLevelObject);
359 void CheckEmptyInitializable(const InitializedEntity &Entity,
363 InitListChecker(Sema &S, const InitializedEntity &Entity,
364 InitListExpr *IL, QualType &T, bool VerifyOnly,
365 bool TreatUnavailableAsInvalid);
366 bool HadError() { return hadError; }
368 // @brief Retrieves the fully-structured initializer list used for
369 // semantic analysis and code generation.
370 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; }
373 } // end anonymous namespace
375 ExprResult InitListChecker::PerformEmptyInit(Sema &SemaRef,
377 const InitializedEntity &Entity,
379 bool TreatUnavailableAsInvalid) {
380 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc,
382 MultiExprArg SubInit;
384 InitListExpr DummyInitList(SemaRef.Context, Loc, None, Loc);
386 // C++ [dcl.init.aggr]p7:
387 // If there are fewer initializer-clauses in the list than there are
388 // members in the aggregate, then each member not explicitly initialized
390 bool EmptyInitList = SemaRef.getLangOpts().CPlusPlus11 &&
391 Entity.getType()->getBaseElementTypeUnsafe()->isRecordType();
394 // shall be initialized [...] from an empty initializer list.
396 // We apply the resolution of this DR to C++11 but not C++98, since C++98
397 // does not have useful semantics for initialization from an init list.
398 // We treat this as copy-initialization, because aggregate initialization
399 // always performs copy-initialization on its elements.
401 // Only do this if we're initializing a class type, to avoid filling in
402 // the initializer list where possible.
403 InitExpr = VerifyOnly ? &DummyInitList : new (SemaRef.Context)
404 InitListExpr(SemaRef.Context, Loc, None, Loc);
405 InitExpr->setType(SemaRef.Context.VoidTy);
407 Kind = InitializationKind::CreateCopy(Loc, Loc);
410 // shall be value-initialized.
413 InitializationSequence InitSeq(SemaRef, Entity, Kind, SubInit);
414 // libstdc++4.6 marks the vector default constructor as explicit in
415 // _GLIBCXX_DEBUG mode, so recover using the C++03 logic in that case.
416 // stlport does so too. Look for std::__debug for libstdc++, and for
417 // std:: for stlport. This is effectively a compiler-side implementation of
419 if (!InitSeq && EmptyInitList && InitSeq.getFailureKind() ==
420 InitializationSequence::FK_ExplicitConstructor) {
421 OverloadCandidateSet::iterator Best;
422 OverloadingResult O =
423 InitSeq.getFailedCandidateSet()
424 .BestViableFunction(SemaRef, Kind.getLocation(), Best);
426 assert(O == OR_Success && "Inconsistent overload resolution");
427 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
428 CXXRecordDecl *R = CtorDecl->getParent();
430 if (CtorDecl->getMinRequiredArguments() == 0 &&
431 CtorDecl->isExplicit() && R->getDeclName() &&
432 SemaRef.SourceMgr.isInSystemHeader(CtorDecl->getLocation())) {
433 bool IsInStd = false;
434 for (NamespaceDecl *ND = dyn_cast<NamespaceDecl>(R->getDeclContext());
435 ND && !IsInStd; ND = dyn_cast<NamespaceDecl>(ND->getParent())) {
436 if (SemaRef.getStdNamespace()->InEnclosingNamespaceSetOf(ND))
440 if (IsInStd && llvm::StringSwitch<bool>(R->getName())
441 .Cases("basic_string", "deque", "forward_list", true)
442 .Cases("list", "map", "multimap", "multiset", true)
443 .Cases("priority_queue", "queue", "set", "stack", true)
444 .Cases("unordered_map", "unordered_set", "vector", true)
446 InitSeq.InitializeFrom(
448 InitializationKind::CreateValue(Loc, Loc, Loc, true),
449 MultiExprArg(), /*TopLevelOfInitList=*/false,
450 TreatUnavailableAsInvalid);
451 // Emit a warning for this. System header warnings aren't shown
452 // by default, but people working on system headers should see it.
454 SemaRef.Diag(CtorDecl->getLocation(),
455 diag::warn_invalid_initializer_from_system_header);
456 if (Entity.getKind() == InitializedEntity::EK_Member)
457 SemaRef.Diag(Entity.getDecl()->getLocation(),
458 diag::note_used_in_initialization_here);
459 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement)
460 SemaRef.Diag(Loc, diag::note_used_in_initialization_here);
467 InitSeq.Diagnose(SemaRef, Entity, Kind, SubInit);
468 if (Entity.getKind() == InitializedEntity::EK_Member)
469 SemaRef.Diag(Entity.getDecl()->getLocation(),
470 diag::note_in_omitted_aggregate_initializer)
471 << /*field*/1 << Entity.getDecl();
472 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement) {
473 bool IsTrailingArrayNewMember =
474 Entity.getParent() &&
475 Entity.getParent()->isVariableLengthArrayNew();
476 SemaRef.Diag(Loc, diag::note_in_omitted_aggregate_initializer)
477 << (IsTrailingArrayNewMember ? 2 : /*array element*/0)
478 << Entity.getElementIndex();
484 return VerifyOnly ? ExprResult(static_cast<Expr *>(nullptr))
485 : InitSeq.Perform(SemaRef, Entity, Kind, SubInit);
488 void InitListChecker::CheckEmptyInitializable(const InitializedEntity &Entity,
489 SourceLocation Loc) {
491 "CheckEmptyInitializable is only inteded for verification mode.");
492 if (PerformEmptyInit(SemaRef, Loc, Entity, /*VerifyOnly*/true,
493 TreatUnavailableAsInvalid).isInvalid())
497 void InitListChecker::FillInEmptyInitForBase(
498 unsigned Init, const CXXBaseSpecifier &Base,
499 const InitializedEntity &ParentEntity, InitListExpr *ILE,
500 bool &RequiresSecondPass, bool FillWithNoInit) {
501 assert(Init < ILE->getNumInits() && "should have been expanded");
503 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
504 SemaRef.Context, &Base, false, &ParentEntity);
506 if (!ILE->getInit(Init)) {
507 ExprResult BaseInit =
508 FillWithNoInit ? new (SemaRef.Context) NoInitExpr(Base.getType())
509 : PerformEmptyInit(SemaRef, ILE->getLocEnd(), BaseEntity,
510 /*VerifyOnly*/ false,
511 TreatUnavailableAsInvalid);
512 if (BaseInit.isInvalid()) {
517 ILE->setInit(Init, BaseInit.getAs<Expr>());
518 } else if (InitListExpr *InnerILE =
519 dyn_cast<InitListExpr>(ILE->getInit(Init))) {
520 FillInEmptyInitializations(BaseEntity, InnerILE,
521 RequiresSecondPass, FillWithNoInit);
522 } else if (DesignatedInitUpdateExpr *InnerDIUE =
523 dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init))) {
524 FillInEmptyInitializations(BaseEntity, InnerDIUE->getUpdater(),
525 RequiresSecondPass, /*FillWithNoInit =*/true);
529 void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
530 const InitializedEntity &ParentEntity,
532 bool &RequiresSecondPass,
533 bool FillWithNoInit) {
534 SourceLocation Loc = ILE->getLocEnd();
535 unsigned NumInits = ILE->getNumInits();
536 InitializedEntity MemberEntity
537 = InitializedEntity::InitializeMember(Field, &ParentEntity);
539 if (const RecordType *RType = ILE->getType()->getAs<RecordType>())
540 if (!RType->getDecl()->isUnion())
541 assert(Init < NumInits && "This ILE should have been expanded");
543 if (Init >= NumInits || !ILE->getInit(Init)) {
544 if (FillWithNoInit) {
545 Expr *Filler = new (SemaRef.Context) NoInitExpr(Field->getType());
547 ILE->setInit(Init, Filler);
549 ILE->updateInit(SemaRef.Context, Init, Filler);
552 // C++1y [dcl.init.aggr]p7:
553 // If there are fewer initializer-clauses in the list than there are
554 // members in the aggregate, then each member not explicitly initialized
555 // shall be initialized from its brace-or-equal-initializer [...]
556 if (Field->hasInClassInitializer()) {
557 ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
558 if (DIE.isInvalid()) {
563 ILE->setInit(Init, DIE.get());
565 ILE->updateInit(SemaRef.Context, Init, DIE.get());
566 RequiresSecondPass = true;
571 if (Field->getType()->isReferenceType()) {
572 // C++ [dcl.init.aggr]p9:
573 // If an incomplete or empty initializer-list leaves a
574 // member of reference type uninitialized, the program is
576 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized)
578 << ILE->getSyntacticForm()->getSourceRange();
579 SemaRef.Diag(Field->getLocation(),
580 diag::note_uninit_reference_member);
585 ExprResult MemberInit = PerformEmptyInit(SemaRef, Loc, MemberEntity,
587 TreatUnavailableAsInvalid);
588 if (MemberInit.isInvalid()) {
595 } else if (Init < NumInits) {
596 ILE->setInit(Init, MemberInit.getAs<Expr>());
597 } else if (!isa<ImplicitValueInitExpr>(MemberInit.get())) {
598 // Empty initialization requires a constructor call, so
599 // extend the initializer list to include the constructor
600 // call and make a note that we'll need to take another pass
601 // through the initializer list.
602 ILE->updateInit(SemaRef.Context, Init, MemberInit.getAs<Expr>());
603 RequiresSecondPass = true;
605 } else if (InitListExpr *InnerILE
606 = dyn_cast<InitListExpr>(ILE->getInit(Init)))
607 FillInEmptyInitializations(MemberEntity, InnerILE,
608 RequiresSecondPass, FillWithNoInit);
609 else if (DesignatedInitUpdateExpr *InnerDIUE
610 = dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init)))
611 FillInEmptyInitializations(MemberEntity, InnerDIUE->getUpdater(),
612 RequiresSecondPass, /*FillWithNoInit =*/ true);
615 /// Recursively replaces NULL values within the given initializer list
616 /// with expressions that perform value-initialization of the
617 /// appropriate type.
619 InitListChecker::FillInEmptyInitializations(const InitializedEntity &Entity,
621 bool &RequiresSecondPass,
622 bool FillWithNoInit) {
623 assert((ILE->getType() != SemaRef.Context.VoidTy) &&
624 "Should not have void type");
626 // A transparent ILE is not performing aggregate initialization and should
628 if (ILE->isTransparent())
631 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
632 const RecordDecl *RDecl = RType->getDecl();
633 if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
634 FillInEmptyInitForField(0, ILE->getInitializedFieldInUnion(),
635 Entity, ILE, RequiresSecondPass, FillWithNoInit);
636 else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
637 cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
638 for (auto *Field : RDecl->fields()) {
639 if (Field->hasInClassInitializer()) {
640 FillInEmptyInitForField(0, Field, Entity, ILE, RequiresSecondPass,
646 // The fields beyond ILE->getNumInits() are default initialized, so in
647 // order to leave them uninitialized, the ILE is expanded and the extra
648 // fields are then filled with NoInitExpr.
649 unsigned NumElems = numStructUnionElements(ILE->getType());
650 if (RDecl->hasFlexibleArrayMember())
652 if (ILE->getNumInits() < NumElems)
653 ILE->resizeInits(SemaRef.Context, NumElems);
657 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RDecl)) {
658 for (auto &Base : CXXRD->bases()) {
662 FillInEmptyInitForBase(Init, Base, Entity, ILE, RequiresSecondPass,
668 for (auto *Field : RDecl->fields()) {
669 if (Field->isUnnamedBitfield())
675 FillInEmptyInitForField(Init, Field, Entity, ILE, RequiresSecondPass,
682 // Only look at the first initialization of a union.
683 if (RDecl->isUnion())
691 QualType ElementType;
693 InitializedEntity ElementEntity = Entity;
694 unsigned NumInits = ILE->getNumInits();
695 unsigned NumElements = NumInits;
696 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) {
697 ElementType = AType->getElementType();
698 if (const auto *CAType = dyn_cast<ConstantArrayType>(AType))
699 NumElements = CAType->getSize().getZExtValue();
700 // For an array new with an unknown bound, ask for one additional element
701 // in order to populate the array filler.
702 if (Entity.isVariableLengthArrayNew())
704 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
706 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) {
707 ElementType = VType->getElementType();
708 NumElements = VType->getNumElements();
709 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
712 ElementType = ILE->getType();
714 for (unsigned Init = 0; Init != NumElements; ++Init) {
718 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement ||
719 ElementEntity.getKind() == InitializedEntity::EK_VectorElement)
720 ElementEntity.setElementIndex(Init);
722 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : nullptr);
723 if (!InitExpr && Init < NumInits && ILE->hasArrayFiller())
724 ILE->setInit(Init, ILE->getArrayFiller());
725 else if (!InitExpr && !ILE->hasArrayFiller()) {
726 Expr *Filler = nullptr;
729 Filler = new (SemaRef.Context) NoInitExpr(ElementType);
731 ExprResult ElementInit = PerformEmptyInit(SemaRef, ILE->getLocEnd(),
734 TreatUnavailableAsInvalid);
735 if (ElementInit.isInvalid()) {
740 Filler = ElementInit.getAs<Expr>();
745 } else if (Init < NumInits) {
746 // For arrays, just set the expression used for value-initialization
747 // of the "holes" in the array.
748 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement)
749 ILE->setArrayFiller(Filler);
751 ILE->setInit(Init, Filler);
753 // For arrays, just set the expression used for value-initialization
754 // of the rest of elements and exit.
755 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) {
756 ILE->setArrayFiller(Filler);
760 if (!isa<ImplicitValueInitExpr>(Filler) && !isa<NoInitExpr>(Filler)) {
761 // Empty initialization requires a constructor call, so
762 // extend the initializer list to include the constructor
763 // call and make a note that we'll need to take another pass
764 // through the initializer list.
765 ILE->updateInit(SemaRef.Context, Init, Filler);
766 RequiresSecondPass = true;
769 } else if (InitListExpr *InnerILE
770 = dyn_cast_or_null<InitListExpr>(InitExpr))
771 FillInEmptyInitializations(ElementEntity, InnerILE, RequiresSecondPass,
773 else if (DesignatedInitUpdateExpr *InnerDIUE
774 = dyn_cast_or_null<DesignatedInitUpdateExpr>(InitExpr))
775 FillInEmptyInitializations(ElementEntity, InnerDIUE->getUpdater(),
776 RequiresSecondPass, /*FillWithNoInit =*/ true);
780 InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity,
781 InitListExpr *IL, QualType &T,
783 bool TreatUnavailableAsInvalid)
784 : SemaRef(S), VerifyOnly(VerifyOnly),
785 TreatUnavailableAsInvalid(TreatUnavailableAsInvalid) {
786 // FIXME: Check that IL isn't already the semantic form of some other
787 // InitListExpr. If it is, we'd create a broken AST.
791 FullyStructuredList =
792 getStructuredSubobjectInit(IL, 0, T, nullptr, 0, IL->getSourceRange());
793 CheckExplicitInitList(Entity, IL, T, FullyStructuredList,
794 /*TopLevelObject=*/true);
796 if (!hadError && !VerifyOnly) {
797 bool RequiresSecondPass = false;
798 FillInEmptyInitializations(Entity, FullyStructuredList, RequiresSecondPass);
799 if (RequiresSecondPass && !hadError)
800 FillInEmptyInitializations(Entity, FullyStructuredList,
805 int InitListChecker::numArrayElements(QualType DeclType) {
806 // FIXME: use a proper constant
807 int maxElements = 0x7FFFFFFF;
808 if (const ConstantArrayType *CAT =
809 SemaRef.Context.getAsConstantArrayType(DeclType)) {
810 maxElements = static_cast<int>(CAT->getSize().getZExtValue());
815 int InitListChecker::numStructUnionElements(QualType DeclType) {
816 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
817 int InitializableMembers = 0;
818 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(structDecl))
819 InitializableMembers += CXXRD->getNumBases();
820 for (const auto *Field : structDecl->fields())
821 if (!Field->isUnnamedBitfield())
822 ++InitializableMembers;
824 if (structDecl->isUnion())
825 return std::min(InitializableMembers, 1);
826 return InitializableMembers - structDecl->hasFlexibleArrayMember();
829 /// Check whether the range of the initializer \p ParentIList from element
830 /// \p Index onwards can be used to initialize an object of type \p T. Update
831 /// \p Index to indicate how many elements of the list were consumed.
833 /// This also fills in \p StructuredList, from element \p StructuredIndex
834 /// onwards, with the fully-braced, desugared form of the initialization.
835 void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity,
836 InitListExpr *ParentIList,
837 QualType T, unsigned &Index,
838 InitListExpr *StructuredList,
839 unsigned &StructuredIndex) {
842 if (T->isArrayType())
843 maxElements = numArrayElements(T);
844 else if (T->isRecordType())
845 maxElements = numStructUnionElements(T);
846 else if (T->isVectorType())
847 maxElements = T->getAs<VectorType>()->getNumElements();
849 llvm_unreachable("CheckImplicitInitList(): Illegal type");
851 if (maxElements == 0) {
853 SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(),
854 diag::err_implicit_empty_initializer);
860 // Build a structured initializer list corresponding to this subobject.
861 InitListExpr *StructuredSubobjectInitList
862 = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList,
864 SourceRange(ParentIList->getInit(Index)->getLocStart(),
865 ParentIList->getSourceRange().getEnd()));
866 unsigned StructuredSubobjectInitIndex = 0;
868 // Check the element types and build the structural subobject.
869 unsigned StartIndex = Index;
870 CheckListElementTypes(Entity, ParentIList, T,
871 /*SubobjectIsDesignatorContext=*/false, Index,
872 StructuredSubobjectInitList,
873 StructuredSubobjectInitIndex);
876 StructuredSubobjectInitList->setType(T);
878 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1);
879 // Update the structured sub-object initializer so that it's ending
880 // range corresponds with the end of the last initializer it used.
881 if (EndIndex < ParentIList->getNumInits() &&
882 ParentIList->getInit(EndIndex)) {
883 SourceLocation EndLoc
884 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd();
885 StructuredSubobjectInitList->setRBraceLoc(EndLoc);
888 // Complain about missing braces.
889 if (T->isArrayType() || T->isRecordType()) {
890 SemaRef.Diag(StructuredSubobjectInitList->getLocStart(),
891 diag::warn_missing_braces)
892 << StructuredSubobjectInitList->getSourceRange()
893 << FixItHint::CreateInsertion(
894 StructuredSubobjectInitList->getLocStart(), "{")
895 << FixItHint::CreateInsertion(
896 SemaRef.getLocForEndOfToken(
897 StructuredSubobjectInitList->getLocEnd()),
903 /// Warn that \p Entity was of scalar type and was initialized by a
904 /// single-element braced initializer list.
905 static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
906 SourceRange Braces) {
907 // Don't warn during template instantiation. If the initialization was
908 // non-dependent, we warned during the initial parse; otherwise, the
909 // type might not be scalar in some uses of the template.
910 if (S.inTemplateInstantiation())
915 switch (Entity.getKind()) {
916 case InitializedEntity::EK_VectorElement:
917 case InitializedEntity::EK_ComplexElement:
918 case InitializedEntity::EK_ArrayElement:
919 case InitializedEntity::EK_Parameter:
920 case InitializedEntity::EK_Parameter_CF_Audited:
921 case InitializedEntity::EK_Result:
922 // Extra braces here are suspicious.
923 DiagID = diag::warn_braces_around_scalar_init;
926 case InitializedEntity::EK_Member:
927 // Warn on aggregate initialization but not on ctor init list or
928 // default member initializer.
929 if (Entity.getParent())
930 DiagID = diag::warn_braces_around_scalar_init;
933 case InitializedEntity::EK_Variable:
934 case InitializedEntity::EK_LambdaCapture:
935 // No warning, might be direct-list-initialization.
936 // FIXME: Should we warn for copy-list-initialization in these cases?
939 case InitializedEntity::EK_New:
940 case InitializedEntity::EK_Temporary:
941 case InitializedEntity::EK_CompoundLiteralInit:
942 // No warning, braces are part of the syntax of the underlying construct.
945 case InitializedEntity::EK_RelatedResult:
946 // No warning, we already warned when initializing the result.
949 case InitializedEntity::EK_Exception:
950 case InitializedEntity::EK_Base:
951 case InitializedEntity::EK_Delegating:
952 case InitializedEntity::EK_BlockElement:
953 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
954 case InitializedEntity::EK_Binding:
955 llvm_unreachable("unexpected braced scalar init");
959 S.Diag(Braces.getBegin(), DiagID)
961 << FixItHint::CreateRemoval(Braces.getBegin())
962 << FixItHint::CreateRemoval(Braces.getEnd());
966 /// Check whether the initializer \p IList (that was written with explicit
967 /// braces) can be used to initialize an object of type \p T.
969 /// This also fills in \p StructuredList with the fully-braced, desugared
970 /// form of the initialization.
971 void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity,
972 InitListExpr *IList, QualType &T,
973 InitListExpr *StructuredList,
974 bool TopLevelObject) {
976 SyntacticToSemantic[IList] = StructuredList;
977 StructuredList->setSyntacticForm(IList);
980 unsigned Index = 0, StructuredIndex = 0;
981 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true,
982 Index, StructuredList, StructuredIndex, TopLevelObject);
985 if (!ExprTy->isArrayType())
986 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context);
987 IList->setType(ExprTy);
988 StructuredList->setType(ExprTy);
993 if (Index < IList->getNumInits()) {
994 // We have leftover initializers
996 if (SemaRef.getLangOpts().CPlusPlus ||
997 (SemaRef.getLangOpts().OpenCL &&
998 IList->getType()->isVectorType())) {
1004 if (StructuredIndex == 1 &&
1005 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) ==
1007 unsigned DK = diag::ext_excess_initializers_in_char_array_initializer;
1008 if (SemaRef.getLangOpts().CPlusPlus) {
1009 DK = diag::err_excess_initializers_in_char_array_initializer;
1013 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK)
1014 << IList->getInit(Index)->getSourceRange();
1015 } else if (!T->isIncompleteType()) {
1016 // Don't complain for incomplete types, since we'll get an error
1018 QualType CurrentObjectType = StructuredList->getType();
1020 CurrentObjectType->isArrayType()? 0 :
1021 CurrentObjectType->isVectorType()? 1 :
1022 CurrentObjectType->isScalarType()? 2 :
1023 CurrentObjectType->isUnionType()? 3 :
1026 unsigned DK = diag::ext_excess_initializers;
1027 if (SemaRef.getLangOpts().CPlusPlus) {
1028 DK = diag::err_excess_initializers;
1031 if (SemaRef.getLangOpts().OpenCL && initKind == 1) {
1032 DK = diag::err_excess_initializers;
1036 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK)
1037 << initKind << IList->getInit(Index)->getSourceRange();
1041 if (!VerifyOnly && T->isScalarType() &&
1042 IList->getNumInits() == 1 && !isa<InitListExpr>(IList->getInit(0)))
1043 warnBracedScalarInit(SemaRef, Entity, IList->getSourceRange());
1046 void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity,
1047 InitListExpr *IList,
1049 bool SubobjectIsDesignatorContext,
1051 InitListExpr *StructuredList,
1052 unsigned &StructuredIndex,
1053 bool TopLevelObject) {
1054 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) {
1055 // Explicitly braced initializer for complex type can be real+imaginary
1057 CheckComplexType(Entity, IList, DeclType, Index,
1058 StructuredList, StructuredIndex);
1059 } else if (DeclType->isScalarType()) {
1060 CheckScalarType(Entity, IList, DeclType, Index,
1061 StructuredList, StructuredIndex);
1062 } else if (DeclType->isVectorType()) {
1063 CheckVectorType(Entity, IList, DeclType, Index,
1064 StructuredList, StructuredIndex);
1065 } else if (DeclType->isRecordType()) {
1066 assert(DeclType->isAggregateType() &&
1067 "non-aggregate records should be handed in CheckSubElementType");
1068 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1070 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
1071 CXXRecordDecl::base_class_iterator());
1072 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1073 Bases = CXXRD->bases();
1074 CheckStructUnionTypes(Entity, IList, DeclType, Bases, RD->field_begin(),
1075 SubobjectIsDesignatorContext, Index, StructuredList,
1076 StructuredIndex, TopLevelObject);
1077 } else if (DeclType->isArrayType()) {
1079 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()),
1081 CheckArrayType(Entity, IList, DeclType, Zero,
1082 SubobjectIsDesignatorContext, Index,
1083 StructuredList, StructuredIndex);
1084 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) {
1085 // This type is invalid, issue a diagnostic.
1088 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type)
1091 } else if (DeclType->isReferenceType()) {
1092 CheckReferenceType(Entity, IList, DeclType, Index,
1093 StructuredList, StructuredIndex);
1094 } else if (DeclType->isObjCObjectType()) {
1096 SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class)
1101 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type)
1107 void InitListChecker::CheckSubElementType(const InitializedEntity &Entity,
1108 InitListExpr *IList,
1111 InitListExpr *StructuredList,
1112 unsigned &StructuredIndex) {
1113 Expr *expr = IList->getInit(Index);
1115 if (ElemType->isReferenceType())
1116 return CheckReferenceType(Entity, IList, ElemType, Index,
1117 StructuredList, StructuredIndex);
1119 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) {
1120 if (SubInitList->getNumInits() == 1 &&
1121 IsStringInit(SubInitList->getInit(0), ElemType, SemaRef.Context) ==
1123 expr = SubInitList->getInit(0);
1124 } else if (!SemaRef.getLangOpts().CPlusPlus) {
1125 InitListExpr *InnerStructuredList
1126 = getStructuredSubobjectInit(IList, Index, ElemType,
1127 StructuredList, StructuredIndex,
1128 SubInitList->getSourceRange(), true);
1129 CheckExplicitInitList(Entity, SubInitList, ElemType,
1130 InnerStructuredList);
1132 if (!hadError && !VerifyOnly) {
1133 bool RequiresSecondPass = false;
1134 FillInEmptyInitializations(Entity, InnerStructuredList,
1135 RequiresSecondPass);
1136 if (RequiresSecondPass && !hadError)
1137 FillInEmptyInitializations(Entity, InnerStructuredList,
1138 RequiresSecondPass);
1144 // C++ initialization is handled later.
1145 } else if (isa<ImplicitValueInitExpr>(expr)) {
1146 // This happens during template instantiation when we see an InitListExpr
1147 // that we've already checked once.
1148 assert(SemaRef.Context.hasSameType(expr->getType(), ElemType) &&
1149 "found implicit initialization for the wrong type");
1151 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1156 if (SemaRef.getLangOpts().CPlusPlus) {
1157 // C++ [dcl.init.aggr]p2:
1158 // Each member is copy-initialized from the corresponding
1159 // initializer-clause.
1161 // FIXME: Better EqualLoc?
1162 InitializationKind Kind =
1163 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation());
1164 InitializationSequence Seq(SemaRef, Entity, Kind, expr,
1165 /*TopLevelOfInitList*/ true);
1167 // C++14 [dcl.init.aggr]p13:
1168 // If the assignment-expression can initialize a member, the member is
1169 // initialized. Otherwise [...] brace elision is assumed
1171 // Brace elision is never performed if the element is not an
1172 // assignment-expression.
1173 if (Seq || isa<InitListExpr>(expr)) {
1176 Seq.Perform(SemaRef, Entity, Kind, expr);
1177 if (Result.isInvalid())
1180 UpdateStructuredListElement(StructuredList, StructuredIndex,
1181 Result.getAs<Expr>());
1188 // Fall through for subaggregate initialization
1189 } else if (ElemType->isScalarType() || ElemType->isAtomicType()) {
1190 // FIXME: Need to handle atomic aggregate types with implicit init lists.
1191 return CheckScalarType(Entity, IList, ElemType, Index,
1192 StructuredList, StructuredIndex);
1193 } else if (const ArrayType *arrayType =
1194 SemaRef.Context.getAsArrayType(ElemType)) {
1195 // arrayType can be incomplete if we're initializing a flexible
1196 // array member. There's nothing we can do with the completed
1197 // type here, though.
1199 if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) {
1201 CheckStringInit(expr, ElemType, arrayType, SemaRef);
1202 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1208 // Fall through for subaggregate initialization.
1211 assert((ElemType->isRecordType() || ElemType->isVectorType() ||
1212 ElemType->isOpenCLSpecificType()) && "Unexpected type");
1216 // The initializer for a structure or union object that has
1217 // automatic storage duration shall be either an initializer
1218 // list as described below, or a single expression that has
1219 // compatible structure or union type. In the latter case, the
1220 // initial value of the object, including unnamed members, is
1221 // that of the expression.
1222 ExprResult ExprRes = expr;
1223 if (SemaRef.CheckSingleAssignmentConstraints(
1224 ElemType, ExprRes, !VerifyOnly) != Sema::Incompatible) {
1225 if (ExprRes.isInvalid())
1228 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.get());
1229 if (ExprRes.isInvalid())
1232 UpdateStructuredListElement(StructuredList, StructuredIndex,
1233 ExprRes.getAs<Expr>());
1238 // Fall through for subaggregate initialization
1241 // C++ [dcl.init.aggr]p12:
1243 // [...] Otherwise, if the member is itself a non-empty
1244 // subaggregate, brace elision is assumed and the initializer is
1245 // considered for the initialization of the first member of
1246 // the subaggregate.
1247 // OpenCL vector initializer is handled elsewhere.
1248 if ((!SemaRef.getLangOpts().OpenCL && ElemType->isVectorType()) ||
1249 ElemType->isAggregateType()) {
1250 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList,
1255 // We cannot initialize this element, so let
1256 // PerformCopyInitialization produce the appropriate diagnostic.
1257 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), expr,
1258 /*TopLevelOfInitList=*/true);
1266 void InitListChecker::CheckComplexType(const InitializedEntity &Entity,
1267 InitListExpr *IList, QualType DeclType,
1269 InitListExpr *StructuredList,
1270 unsigned &StructuredIndex) {
1271 assert(Index == 0 && "Index in explicit init list must be zero");
1273 // As an extension, clang supports complex initializers, which initialize
1274 // a complex number component-wise. When an explicit initializer list for
1275 // a complex number contains two two initializers, this extension kicks in:
1276 // it exepcts the initializer list to contain two elements convertible to
1277 // the element type of the complex type. The first element initializes
1278 // the real part, and the second element intitializes the imaginary part.
1280 if (IList->getNumInits() != 2)
1281 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1284 // This is an extension in C. (The builtin _Complex type does not exist
1285 // in the C++ standard.)
1286 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly)
1287 SemaRef.Diag(IList->getLocStart(), diag::ext_complex_component_init)
1288 << IList->getSourceRange();
1290 // Initialize the complex number.
1291 QualType elementType = DeclType->getAs<ComplexType>()->getElementType();
1292 InitializedEntity ElementEntity =
1293 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1295 for (unsigned i = 0; i < 2; ++i) {
1296 ElementEntity.setElementIndex(Index);
1297 CheckSubElementType(ElementEntity, IList, elementType, Index,
1298 StructuredList, StructuredIndex);
1302 void InitListChecker::CheckScalarType(const InitializedEntity &Entity,
1303 InitListExpr *IList, QualType DeclType,
1305 InitListExpr *StructuredList,
1306 unsigned &StructuredIndex) {
1307 if (Index >= IList->getNumInits()) {
1309 SemaRef.Diag(IList->getLocStart(),
1310 SemaRef.getLangOpts().CPlusPlus11 ?
1311 diag::warn_cxx98_compat_empty_scalar_initializer :
1312 diag::err_empty_scalar_initializer)
1313 << IList->getSourceRange();
1314 hadError = !SemaRef.getLangOpts().CPlusPlus11;
1320 Expr *expr = IList->getInit(Index);
1321 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) {
1322 // FIXME: This is invalid, and accepting it causes overload resolution
1323 // to pick the wrong overload in some corner cases.
1325 SemaRef.Diag(SubIList->getLocStart(),
1326 diag::ext_many_braces_around_scalar_init)
1327 << SubIList->getSourceRange();
1329 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList,
1332 } else if (isa<DesignatedInitExpr>(expr)) {
1334 SemaRef.Diag(expr->getLocStart(),
1335 diag::err_designator_for_scalar_init)
1336 << DeclType << expr->getSourceRange();
1344 if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
1351 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), expr,
1352 /*TopLevelOfInitList=*/true);
1354 Expr *ResultExpr = nullptr;
1356 if (Result.isInvalid())
1357 hadError = true; // types weren't compatible.
1359 ResultExpr = Result.getAs<Expr>();
1361 if (ResultExpr != expr) {
1362 // The type was promoted, update initializer list.
1363 IList->setInit(Index, ResultExpr);
1369 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1373 void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
1374 InitListExpr *IList, QualType DeclType,
1376 InitListExpr *StructuredList,
1377 unsigned &StructuredIndex) {
1378 if (Index >= IList->getNumInits()) {
1379 // FIXME: It would be wonderful if we could point at the actual member. In
1380 // general, it would be useful to pass location information down the stack,
1381 // so that we know the location (or decl) of the "current object" being
1384 SemaRef.Diag(IList->getLocStart(),
1385 diag::err_init_reference_member_uninitialized)
1387 << IList->getSourceRange();
1394 Expr *expr = IList->getInit(Index);
1395 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) {
1397 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list)
1398 << DeclType << IList->getSourceRange();
1406 if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
1413 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), expr,
1414 /*TopLevelOfInitList=*/true);
1416 if (Result.isInvalid())
1419 expr = Result.getAs<Expr>();
1420 IList->setInit(Index, expr);
1425 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1429 void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
1430 InitListExpr *IList, QualType DeclType,
1432 InitListExpr *StructuredList,
1433 unsigned &StructuredIndex) {
1434 const VectorType *VT = DeclType->getAs<VectorType>();
1435 unsigned maxElements = VT->getNumElements();
1436 unsigned numEltsInit = 0;
1437 QualType elementType = VT->getElementType();
1439 if (Index >= IList->getNumInits()) {
1440 // Make sure the element type can be value-initialized.
1442 CheckEmptyInitializable(
1443 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1444 IList->getLocEnd());
1448 if (!SemaRef.getLangOpts().OpenCL) {
1449 // If the initializing element is a vector, try to copy-initialize
1450 // instead of breaking it apart (which is doomed to failure anyway).
1451 Expr *Init = IList->getInit(Index);
1452 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) {
1454 if (!SemaRef.CanPerformCopyInitialization(Entity, Init))
1461 SemaRef.PerformCopyInitialization(Entity, Init->getLocStart(), Init,
1462 /*TopLevelOfInitList=*/true);
1464 Expr *ResultExpr = nullptr;
1465 if (Result.isInvalid())
1466 hadError = true; // types weren't compatible.
1468 ResultExpr = Result.getAs<Expr>();
1470 if (ResultExpr != Init) {
1471 // The type was promoted, update initializer list.
1472 IList->setInit(Index, ResultExpr);
1478 UpdateStructuredListElement(StructuredList, StructuredIndex,
1484 InitializedEntity ElementEntity =
1485 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1487 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
1488 // Don't attempt to go past the end of the init list
1489 if (Index >= IList->getNumInits()) {
1491 CheckEmptyInitializable(ElementEntity, IList->getLocEnd());
1495 ElementEntity.setElementIndex(Index);
1496 CheckSubElementType(ElementEntity, IList, elementType, Index,
1497 StructuredList, StructuredIndex);
1503 bool isBigEndian = SemaRef.Context.getTargetInfo().isBigEndian();
1504 const VectorType *T = Entity.getType()->getAs<VectorType>();
1505 if (isBigEndian && (T->getVectorKind() == VectorType::NeonVector ||
1506 T->getVectorKind() == VectorType::NeonPolyVector)) {
1507 // The ability to use vector initializer lists is a GNU vector extension
1508 // and is unrelated to the NEON intrinsics in arm_neon.h. On little
1509 // endian machines it works fine, however on big endian machines it
1510 // exhibits surprising behaviour:
1512 // uint32x2_t x = {42, 64};
1513 // return vget_lane_u32(x, 0); // Will return 64.
1515 // Because of this, explicitly call out that it is non-portable.
1517 SemaRef.Diag(IList->getLocStart(),
1518 diag::warn_neon_vector_initializer_non_portable);
1520 const char *typeCode;
1521 unsigned typeSize = SemaRef.Context.getTypeSize(elementType);
1523 if (elementType->isFloatingType())
1525 else if (elementType->isSignedIntegerType())
1527 else if (elementType->isUnsignedIntegerType())
1530 llvm_unreachable("Invalid element type!");
1532 SemaRef.Diag(IList->getLocStart(),
1533 SemaRef.Context.getTypeSize(VT) > 64 ?
1534 diag::note_neon_vector_initializer_non_portable_q :
1535 diag::note_neon_vector_initializer_non_portable)
1536 << typeCode << typeSize;
1542 InitializedEntity ElementEntity =
1543 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1545 // OpenCL initializers allows vectors to be constructed from vectors.
1546 for (unsigned i = 0; i < maxElements; ++i) {
1547 // Don't attempt to go past the end of the init list
1548 if (Index >= IList->getNumInits())
1551 ElementEntity.setElementIndex(Index);
1553 QualType IType = IList->getInit(Index)->getType();
1554 if (!IType->isVectorType()) {
1555 CheckSubElementType(ElementEntity, IList, elementType, Index,
1556 StructuredList, StructuredIndex);
1560 const VectorType *IVT = IType->getAs<VectorType>();
1561 unsigned numIElts = IVT->getNumElements();
1563 if (IType->isExtVectorType())
1564 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts);
1566 VecType = SemaRef.Context.getVectorType(elementType, numIElts,
1567 IVT->getVectorKind());
1568 CheckSubElementType(ElementEntity, IList, VecType, Index,
1569 StructuredList, StructuredIndex);
1570 numEltsInit += numIElts;
1574 // OpenCL requires all elements to be initialized.
1575 if (numEltsInit != maxElements) {
1577 SemaRef.Diag(IList->getLocStart(),
1578 diag::err_vector_incorrect_num_initializers)
1579 << (numEltsInit < maxElements) << maxElements << numEltsInit;
1584 void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
1585 InitListExpr *IList, QualType &DeclType,
1586 llvm::APSInt elementIndex,
1587 bool SubobjectIsDesignatorContext,
1589 InitListExpr *StructuredList,
1590 unsigned &StructuredIndex) {
1591 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
1593 // Check for the special-case of initializing an array with a string.
1594 if (Index < IList->getNumInits()) {
1595 if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
1597 // We place the string literal directly into the resulting
1598 // initializer list. This is the only place where the structure
1599 // of the structured initializer list doesn't match exactly,
1600 // because doing so would involve allocating one character
1601 // constant for each string.
1603 CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef);
1604 UpdateStructuredListElement(StructuredList, StructuredIndex,
1605 IList->getInit(Index));
1606 StructuredList->resizeInits(SemaRef.Context, StructuredIndex);
1612 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) {
1613 // Check for VLAs; in standard C it would be possible to check this
1614 // earlier, but I don't know where clang accepts VLAs (gcc accepts
1615 // them in all sorts of strange places).
1617 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(),
1618 diag::err_variable_object_no_init)
1619 << VAT->getSizeExpr()->getSourceRange();
1626 // We might know the maximum number of elements in advance.
1627 llvm::APSInt maxElements(elementIndex.getBitWidth(),
1628 elementIndex.isUnsigned());
1629 bool maxElementsKnown = false;
1630 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) {
1631 maxElements = CAT->getSize();
1632 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth());
1633 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1634 maxElementsKnown = true;
1637 QualType elementType = arrayType->getElementType();
1638 while (Index < IList->getNumInits()) {
1639 Expr *Init = IList->getInit(Index);
1640 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1641 // If we're not the subobject that matches up with the '{' for
1642 // the designator, we shouldn't be handling the
1643 // designator. Return immediately.
1644 if (!SubobjectIsDesignatorContext)
1647 // Handle this designated initializer. elementIndex will be
1648 // updated to be the next array element we'll initialize.
1649 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1650 DeclType, nullptr, &elementIndex, Index,
1651 StructuredList, StructuredIndex, true,
1657 if (elementIndex.getBitWidth() > maxElements.getBitWidth())
1658 maxElements = maxElements.extend(elementIndex.getBitWidth());
1659 else if (elementIndex.getBitWidth() < maxElements.getBitWidth())
1660 elementIndex = elementIndex.extend(maxElements.getBitWidth());
1661 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1663 // If the array is of incomplete type, keep track of the number of
1664 // elements in the initializer.
1665 if (!maxElementsKnown && elementIndex > maxElements)
1666 maxElements = elementIndex;
1671 // If we know the maximum number of elements, and we've already
1672 // hit it, stop consuming elements in the initializer list.
1673 if (maxElementsKnown && elementIndex == maxElements)
1676 InitializedEntity ElementEntity =
1677 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex,
1679 // Check this element.
1680 CheckSubElementType(ElementEntity, IList, elementType, Index,
1681 StructuredList, StructuredIndex);
1684 // If the array is of incomplete type, keep track of the number of
1685 // elements in the initializer.
1686 if (!maxElementsKnown && elementIndex > maxElements)
1687 maxElements = elementIndex;
1689 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) {
1690 // If this is an incomplete array type, the actual type needs to
1691 // be calculated here.
1692 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned());
1693 if (maxElements == Zero && !Entity.isVariableLengthArrayNew()) {
1694 // Sizing an array implicitly to zero is not allowed by ISO C,
1695 // but is supported by GNU.
1696 SemaRef.Diag(IList->getLocStart(),
1697 diag::ext_typecheck_zero_array_size);
1700 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements,
1701 ArrayType::Normal, 0);
1703 if (!hadError && VerifyOnly) {
1704 // If there are any members of the array that get value-initialized, check
1705 // that is possible. That happens if we know the bound and don't have
1706 // enough elements, or if we're performing an array new with an unknown
1708 // FIXME: This needs to detect holes left by designated initializers too.
1709 if ((maxElementsKnown && elementIndex < maxElements) ||
1710 Entity.isVariableLengthArrayNew())
1711 CheckEmptyInitializable(InitializedEntity::InitializeElement(
1712 SemaRef.Context, 0, Entity),
1713 IList->getLocEnd());
1717 bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
1720 bool TopLevelObject) {
1721 // Handle GNU flexible array initializers.
1722 unsigned FlexArrayDiag;
1723 if (isa<InitListExpr>(InitExpr) &&
1724 cast<InitListExpr>(InitExpr)->getNumInits() == 0) {
1725 // Empty flexible array init always allowed as an extension
1726 FlexArrayDiag = diag::ext_flexible_array_init;
1727 } else if (SemaRef.getLangOpts().CPlusPlus) {
1728 // Disallow flexible array init in C++; it is not required for gcc
1729 // compatibility, and it needs work to IRGen correctly in general.
1730 FlexArrayDiag = diag::err_flexible_array_init;
1731 } else if (!TopLevelObject) {
1732 // Disallow flexible array init on non-top-level object
1733 FlexArrayDiag = diag::err_flexible_array_init;
1734 } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
1735 // Disallow flexible array init on anything which is not a variable.
1736 FlexArrayDiag = diag::err_flexible_array_init;
1737 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) {
1738 // Disallow flexible array init on local variables.
1739 FlexArrayDiag = diag::err_flexible_array_init;
1741 // Allow other cases.
1742 FlexArrayDiag = diag::ext_flexible_array_init;
1746 SemaRef.Diag(InitExpr->getLocStart(),
1748 << InitExpr->getLocStart();
1749 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
1753 return FlexArrayDiag != diag::ext_flexible_array_init;
1756 void InitListChecker::CheckStructUnionTypes(
1757 const InitializedEntity &Entity, InitListExpr *IList, QualType DeclType,
1758 CXXRecordDecl::base_class_range Bases, RecordDecl::field_iterator Field,
1759 bool SubobjectIsDesignatorContext, unsigned &Index,
1760 InitListExpr *StructuredList, unsigned &StructuredIndex,
1761 bool TopLevelObject) {
1762 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
1764 // If the record is invalid, some of it's members are invalid. To avoid
1765 // confusion, we forgo checking the intializer for the entire record.
1766 if (structDecl->isInvalidDecl()) {
1767 // Assume it was supposed to consume a single initializer.
1773 if (DeclType->isUnionType() && IList->getNumInits() == 0) {
1774 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1776 // If there's a default initializer, use it.
1777 if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
1780 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
1781 Field != FieldEnd; ++Field) {
1782 if (Field->hasInClassInitializer()) {
1783 StructuredList->setInitializedFieldInUnion(*Field);
1784 // FIXME: Actually build a CXXDefaultInitExpr?
1790 // Value-initialize the first member of the union that isn't an unnamed
1792 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
1793 Field != FieldEnd; ++Field) {
1794 if (!Field->isUnnamedBitfield()) {
1796 CheckEmptyInitializable(
1797 InitializedEntity::InitializeMember(*Field, &Entity),
1798 IList->getLocEnd());
1800 StructuredList->setInitializedFieldInUnion(*Field);
1807 bool InitializedSomething = false;
1809 // If we have any base classes, they are initialized prior to the fields.
1810 for (auto &Base : Bases) {
1811 Expr *Init = Index < IList->getNumInits() ? IList->getInit(Index) : nullptr;
1812 SourceLocation InitLoc = Init ? Init->getLocStart() : IList->getLocEnd();
1814 // Designated inits always initialize fields, so if we see one, all
1815 // remaining base classes have no explicit initializer.
1816 if (Init && isa<DesignatedInitExpr>(Init))
1819 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
1820 SemaRef.Context, &Base, false, &Entity);
1822 CheckSubElementType(BaseEntity, IList, Base.getType(), Index,
1823 StructuredList, StructuredIndex);
1824 InitializedSomething = true;
1825 } else if (VerifyOnly) {
1826 CheckEmptyInitializable(BaseEntity, InitLoc);
1830 // If structDecl is a forward declaration, this loop won't do
1831 // anything except look at designated initializers; That's okay,
1832 // because an error should get printed out elsewhere. It might be
1833 // worthwhile to skip over the rest of the initializer, though.
1834 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1835 RecordDecl::field_iterator FieldEnd = RD->field_end();
1836 bool CheckForMissingFields = true;
1837 while (Index < IList->getNumInits()) {
1838 Expr *Init = IList->getInit(Index);
1840 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1841 // If we're not the subobject that matches up with the '{' for
1842 // the designator, we shouldn't be handling the
1843 // designator. Return immediately.
1844 if (!SubobjectIsDesignatorContext)
1847 // Handle this designated initializer. Field will be updated to
1848 // the next field that we'll be initializing.
1849 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1850 DeclType, &Field, nullptr, Index,
1851 StructuredList, StructuredIndex,
1852 true, TopLevelObject))
1855 InitializedSomething = true;
1857 // Disable check for missing fields when designators are used.
1858 // This matches gcc behaviour.
1859 CheckForMissingFields = false;
1863 if (Field == FieldEnd) {
1864 // We've run out of fields. We're done.
1868 // We've already initialized a member of a union. We're done.
1869 if (InitializedSomething && DeclType->isUnionType())
1872 // If we've hit the flexible array member at the end, we're done.
1873 if (Field->getType()->isIncompleteArrayType())
1876 if (Field->isUnnamedBitfield()) {
1877 // Don't initialize unnamed bitfields, e.g. "int : 20;"
1882 // Make sure we can use this declaration.
1885 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
1887 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field,
1888 IList->getInit(Index)->getLocStart());
1896 InitializedEntity MemberEntity =
1897 InitializedEntity::InitializeMember(*Field, &Entity);
1898 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
1899 StructuredList, StructuredIndex);
1900 InitializedSomething = true;
1902 if (DeclType->isUnionType() && !VerifyOnly) {
1903 // Initialize the first field within the union.
1904 StructuredList->setInitializedFieldInUnion(*Field);
1910 // Emit warnings for missing struct field initializers.
1911 if (!VerifyOnly && InitializedSomething && CheckForMissingFields &&
1912 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() &&
1913 !DeclType->isUnionType()) {
1914 // It is possible we have one or more unnamed bitfields remaining.
1915 // Find first (if any) named field and emit warning.
1916 for (RecordDecl::field_iterator it = Field, end = RD->field_end();
1918 if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
1919 SemaRef.Diag(IList->getSourceRange().getEnd(),
1920 diag::warn_missing_field_initializers) << *it;
1926 // Check that any remaining fields can be value-initialized.
1927 if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() &&
1928 !Field->getType()->isIncompleteArrayType()) {
1929 // FIXME: Should check for holes left by designated initializers too.
1930 for (; Field != FieldEnd && !hadError; ++Field) {
1931 if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
1932 CheckEmptyInitializable(
1933 InitializedEntity::InitializeMember(*Field, &Entity),
1934 IList->getLocEnd());
1938 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() ||
1939 Index >= IList->getNumInits())
1942 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field,
1949 InitializedEntity MemberEntity =
1950 InitializedEntity::InitializeMember(*Field, &Entity);
1952 if (isa<InitListExpr>(IList->getInit(Index)))
1953 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
1954 StructuredList, StructuredIndex);
1956 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index,
1957 StructuredList, StructuredIndex);
1960 /// \brief Expand a field designator that refers to a member of an
1961 /// anonymous struct or union into a series of field designators that
1962 /// refers to the field within the appropriate subobject.
1964 static void ExpandAnonymousFieldDesignator(Sema &SemaRef,
1965 DesignatedInitExpr *DIE,
1967 IndirectFieldDecl *IndirectField) {
1968 typedef DesignatedInitExpr::Designator Designator;
1970 // Build the replacement designators.
1971 SmallVector<Designator, 4> Replacements;
1972 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(),
1973 PE = IndirectField->chain_end(); PI != PE; ++PI) {
1975 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
1976 DIE->getDesignator(DesigIdx)->getDotLoc(),
1977 DIE->getDesignator(DesigIdx)->getFieldLoc()));
1979 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
1980 SourceLocation(), SourceLocation()));
1981 assert(isa<FieldDecl>(*PI));
1982 Replacements.back().setField(cast<FieldDecl>(*PI));
1985 // Expand the current designator into the set of replacement
1986 // designators, so we have a full subobject path down to where the
1987 // member of the anonymous struct/union is actually stored.
1988 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0],
1989 &Replacements[0] + Replacements.size());
1992 static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef,
1993 DesignatedInitExpr *DIE) {
1994 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1;
1995 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs);
1996 for (unsigned I = 0; I < NumIndexExprs; ++I)
1997 IndexExprs[I] = DIE->getSubExpr(I + 1);
1998 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators(),
2000 DIE->getEqualOrColonLoc(),
2001 DIE->usesGNUSyntax(), DIE->getInit());
2006 // Callback to only accept typo corrections that are for field members of
2007 // the given struct or union.
2008 class FieldInitializerValidatorCCC : public CorrectionCandidateCallback {
2010 explicit FieldInitializerValidatorCCC(RecordDecl *RD)
2013 bool ValidateCandidate(const TypoCorrection &candidate) override {
2014 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>();
2015 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record);
2022 } // end anonymous namespace
2024 /// @brief Check the well-formedness of a C99 designated initializer.
2026 /// Determines whether the designated initializer @p DIE, which
2027 /// resides at the given @p Index within the initializer list @p
2028 /// IList, is well-formed for a current object of type @p DeclType
2029 /// (C99 6.7.8). The actual subobject that this designator refers to
2030 /// within the current subobject is returned in either
2031 /// @p NextField or @p NextElementIndex (whichever is appropriate).
2033 /// @param IList The initializer list in which this designated
2034 /// initializer occurs.
2036 /// @param DIE The designated initializer expression.
2038 /// @param DesigIdx The index of the current designator.
2040 /// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17),
2041 /// into which the designation in @p DIE should refer.
2043 /// @param NextField If non-NULL and the first designator in @p DIE is
2044 /// a field, this will be set to the field declaration corresponding
2045 /// to the field named by the designator.
2047 /// @param NextElementIndex If non-NULL and the first designator in @p
2048 /// DIE is an array designator or GNU array-range designator, this
2049 /// will be set to the last index initialized by this designator.
2051 /// @param Index Index into @p IList where the designated initializer
2054 /// @param StructuredList The initializer list expression that
2055 /// describes all of the subobject initializers in the order they'll
2056 /// actually be initialized.
2058 /// @returns true if there was an error, false otherwise.
2060 InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity,
2061 InitListExpr *IList,
2062 DesignatedInitExpr *DIE,
2064 QualType &CurrentObjectType,
2065 RecordDecl::field_iterator *NextField,
2066 llvm::APSInt *NextElementIndex,
2068 InitListExpr *StructuredList,
2069 unsigned &StructuredIndex,
2070 bool FinishSubobjectInit,
2071 bool TopLevelObject) {
2072 if (DesigIdx == DIE->size()) {
2073 // Check the actual initialization for the designated object type.
2074 bool prevHadError = hadError;
2076 // Temporarily remove the designator expression from the
2077 // initializer list that the child calls see, so that we don't try
2078 // to re-process the designator.
2079 unsigned OldIndex = Index;
2080 IList->setInit(OldIndex, DIE->getInit());
2082 CheckSubElementType(Entity, IList, CurrentObjectType, Index,
2083 StructuredList, StructuredIndex);
2085 // Restore the designated initializer expression in the syntactic
2086 // form of the initializer list.
2087 if (IList->getInit(OldIndex) != DIE->getInit())
2088 DIE->setInit(IList->getInit(OldIndex));
2089 IList->setInit(OldIndex, DIE);
2091 return hadError && !prevHadError;
2094 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx);
2095 bool IsFirstDesignator = (DesigIdx == 0);
2097 assert((IsFirstDesignator || StructuredList) &&
2098 "Need a non-designated initializer list to start from");
2100 // Determine the structural initializer list that corresponds to the
2101 // current subobject.
2102 if (IsFirstDesignator)
2103 StructuredList = SyntacticToSemantic.lookup(IList);
2105 Expr *ExistingInit = StructuredIndex < StructuredList->getNumInits() ?
2106 StructuredList->getInit(StructuredIndex) : nullptr;
2107 if (!ExistingInit && StructuredList->hasArrayFiller())
2108 ExistingInit = StructuredList->getArrayFiller();
2112 getStructuredSubobjectInit(IList, Index, CurrentObjectType,
2113 StructuredList, StructuredIndex,
2114 SourceRange(D->getLocStart(),
2116 else if (InitListExpr *Result = dyn_cast<InitListExpr>(ExistingInit))
2117 StructuredList = Result;
2119 if (DesignatedInitUpdateExpr *E =
2120 dyn_cast<DesignatedInitUpdateExpr>(ExistingInit))
2121 StructuredList = E->getUpdater();
2123 DesignatedInitUpdateExpr *DIUE =
2124 new (SemaRef.Context) DesignatedInitUpdateExpr(SemaRef.Context,
2125 D->getLocStart(), ExistingInit,
2127 StructuredList->updateInit(SemaRef.Context, StructuredIndex, DIUE);
2128 StructuredList = DIUE->getUpdater();
2131 // We need to check on source range validity because the previous
2132 // initializer does not have to be an explicit initializer. e.g.,
2134 // struct P { int a, b; };
2135 // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
2137 // There is an overwrite taking place because the first braced initializer
2138 // list "{ .a = 2 }" already provides value for .p.b (which is zero).
2139 if (ExistingInit->getSourceRange().isValid()) {
2140 // We are creating an initializer list that initializes the
2141 // subobjects of the current object, but there was already an
2142 // initialization that completely initialized the current
2143 // subobject, e.g., by a compound literal:
2145 // struct X { int a, b; };
2146 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2148 // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
2149 // designated initializer re-initializes the whole
2150 // subobject [0], overwriting previous initializers.
2151 SemaRef.Diag(D->getLocStart(),
2152 diag::warn_subobject_initializer_overrides)
2153 << SourceRange(D->getLocStart(), DIE->getLocEnd());
2155 SemaRef.Diag(ExistingInit->getLocStart(),
2156 diag::note_previous_initializer)
2157 << /*FIXME:has side effects=*/0
2158 << ExistingInit->getSourceRange();
2162 assert(StructuredList && "Expected a structured initializer list");
2165 if (D->isFieldDesignator()) {
2168 // If a designator has the form
2172 // then the current object (defined below) shall have
2173 // structure or union type and the identifier shall be the
2174 // name of a member of that type.
2175 const RecordType *RT = CurrentObjectType->getAs<RecordType>();
2177 SourceLocation Loc = D->getDotLoc();
2178 if (Loc.isInvalid())
2179 Loc = D->getFieldLoc();
2181 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr)
2182 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType;
2187 FieldDecl *KnownField = D->getField();
2189 IdentifierInfo *FieldName = D->getFieldName();
2190 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName);
2191 for (NamedDecl *ND : Lookup) {
2192 if (auto *FD = dyn_cast<FieldDecl>(ND)) {
2196 if (auto *IFD = dyn_cast<IndirectFieldDecl>(ND)) {
2197 // In verify mode, don't modify the original.
2199 DIE = CloneDesignatedInitExpr(SemaRef, DIE);
2200 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IFD);
2201 D = DIE->getDesignator(DesigIdx);
2202 KnownField = cast<FieldDecl>(*IFD->chain_begin());
2209 return true; // No typo correction when just trying this out.
2212 // Name lookup found something, but it wasn't a field.
2213 if (!Lookup.empty()) {
2214 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield)
2216 SemaRef.Diag(Lookup.front()->getLocation(),
2217 diag::note_field_designator_found);
2222 // Name lookup didn't find anything.
2223 // Determine whether this was a typo for another field name.
2224 if (TypoCorrection Corrected = SemaRef.CorrectTypo(
2225 DeclarationNameInfo(FieldName, D->getFieldLoc()),
2226 Sema::LookupMemberName, /*Scope=*/nullptr, /*SS=*/nullptr,
2227 llvm::make_unique<FieldInitializerValidatorCCC>(RT->getDecl()),
2228 Sema::CTK_ErrorRecovery, RT->getDecl())) {
2229 SemaRef.diagnoseTypo(
2231 SemaRef.PDiag(diag::err_field_designator_unknown_suggest)
2232 << FieldName << CurrentObjectType);
2233 KnownField = Corrected.getCorrectionDeclAs<FieldDecl>();
2236 // Typo correction didn't find anything.
2237 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown)
2238 << FieldName << CurrentObjectType;
2245 unsigned FieldIndex = 0;
2247 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
2248 FieldIndex = CXXRD->getNumBases();
2250 for (auto *FI : RT->getDecl()->fields()) {
2251 if (FI->isUnnamedBitfield())
2253 if (declaresSameEntity(KnownField, FI)) {
2260 RecordDecl::field_iterator Field =
2261 RecordDecl::field_iterator(DeclContext::decl_iterator(KnownField));
2263 // All of the fields of a union are located at the same place in
2264 // the initializer list.
2265 if (RT->getDecl()->isUnion()) {
2268 FieldDecl *CurrentField = StructuredList->getInitializedFieldInUnion();
2269 if (CurrentField && !declaresSameEntity(CurrentField, *Field)) {
2270 assert(StructuredList->getNumInits() == 1
2271 && "A union should never have more than one initializer!");
2273 Expr *ExistingInit = StructuredList->getInit(0);
2275 // We're about to throw away an initializer, emit warning.
2276 SemaRef.Diag(D->getFieldLoc(),
2277 diag::warn_initializer_overrides)
2278 << D->getSourceRange();
2279 SemaRef.Diag(ExistingInit->getLocStart(),
2280 diag::note_previous_initializer)
2281 << /*FIXME:has side effects=*/0
2282 << ExistingInit->getSourceRange();
2285 // remove existing initializer
2286 StructuredList->resizeInits(SemaRef.Context, 0);
2287 StructuredList->setInitializedFieldInUnion(nullptr);
2290 StructuredList->setInitializedFieldInUnion(*Field);
2294 // Make sure we can use this declaration.
2297 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
2299 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc());
2306 // Update the designator with the field declaration.
2307 D->setField(*Field);
2309 // Make sure that our non-designated initializer list has space
2310 // for a subobject corresponding to this field.
2311 if (FieldIndex >= StructuredList->getNumInits())
2312 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1);
2315 // This designator names a flexible array member.
2316 if (Field->getType()->isIncompleteArrayType()) {
2317 bool Invalid = false;
2318 if ((DesigIdx + 1) != DIE->size()) {
2319 // We can't designate an object within the flexible array
2320 // member (because GCC doesn't allow it).
2322 DesignatedInitExpr::Designator *NextD
2323 = DIE->getDesignator(DesigIdx + 1);
2324 SemaRef.Diag(NextD->getLocStart(),
2325 diag::err_designator_into_flexible_array_member)
2326 << SourceRange(NextD->getLocStart(),
2328 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2334 if (!hadError && !isa<InitListExpr>(DIE->getInit()) &&
2335 !isa<StringLiteral>(DIE->getInit())) {
2336 // The initializer is not an initializer list.
2338 SemaRef.Diag(DIE->getInit()->getLocStart(),
2339 diag::err_flexible_array_init_needs_braces)
2340 << DIE->getInit()->getSourceRange();
2341 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2347 // Check GNU flexible array initializer.
2348 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field,
2357 // Initialize the array.
2358 bool prevHadError = hadError;
2359 unsigned newStructuredIndex = FieldIndex;
2360 unsigned OldIndex = Index;
2361 IList->setInit(Index, DIE->getInit());
2363 InitializedEntity MemberEntity =
2364 InitializedEntity::InitializeMember(*Field, &Entity);
2365 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2366 StructuredList, newStructuredIndex);
2368 IList->setInit(OldIndex, DIE);
2369 if (hadError && !prevHadError) {
2374 StructuredIndex = FieldIndex;
2378 // Recurse to check later designated subobjects.
2379 QualType FieldType = Field->getType();
2380 unsigned newStructuredIndex = FieldIndex;
2382 InitializedEntity MemberEntity =
2383 InitializedEntity::InitializeMember(*Field, &Entity);
2384 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1,
2385 FieldType, nullptr, nullptr, Index,
2386 StructuredList, newStructuredIndex,
2387 FinishSubobjectInit, false))
2391 // Find the position of the next field to be initialized in this
2396 // If this the first designator, our caller will continue checking
2397 // the rest of this struct/class/union subobject.
2398 if (IsFirstDesignator) {
2401 StructuredIndex = FieldIndex;
2405 if (!FinishSubobjectInit)
2408 // We've already initialized something in the union; we're done.
2409 if (RT->getDecl()->isUnion())
2412 // Check the remaining fields within this class/struct/union subobject.
2413 bool prevHadError = hadError;
2416 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
2417 CXXRecordDecl::base_class_iterator());
2418 CheckStructUnionTypes(Entity, IList, CurrentObjectType, NoBases, Field,
2419 false, Index, StructuredList, FieldIndex);
2420 return hadError && !prevHadError;
2425 // If a designator has the form
2427 // [ constant-expression ]
2429 // then the current object (defined below) shall have array
2430 // type and the expression shall be an integer constant
2431 // expression. If the array is of unknown size, any
2432 // nonnegative value is valid.
2434 // Additionally, cope with the GNU extension that permits
2435 // designators of the form
2437 // [ constant-expression ... constant-expression ]
2438 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType);
2441 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array)
2442 << CurrentObjectType;
2447 Expr *IndexExpr = nullptr;
2448 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex;
2449 if (D->isArrayDesignator()) {
2450 IndexExpr = DIE->getArrayIndex(*D);
2451 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context);
2452 DesignatedEndIndex = DesignatedStartIndex;
2454 assert(D->isArrayRangeDesignator() && "Need array-range designator");
2456 DesignatedStartIndex =
2457 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context);
2458 DesignatedEndIndex =
2459 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context);
2460 IndexExpr = DIE->getArrayRangeEnd(*D);
2462 // Codegen can't handle evaluating array range designators that have side
2463 // effects, because we replicate the AST value for each initialized element.
2464 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple
2465 // elements with something that has a side effect, so codegen can emit an
2466 // "error unsupported" error instead of miscompiling the app.
2467 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&&
2468 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly)
2469 FullyStructuredList->sawArrayRangeDesignator();
2472 if (isa<ConstantArrayType>(AT)) {
2473 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false);
2474 DesignatedStartIndex
2475 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth());
2476 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned());
2478 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth());
2479 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned());
2480 if (DesignatedEndIndex >= MaxElements) {
2482 SemaRef.Diag(IndexExpr->getLocStart(),
2483 diag::err_array_designator_too_large)
2484 << DesignatedEndIndex.toString(10) << MaxElements.toString(10)
2485 << IndexExpr->getSourceRange();
2490 unsigned DesignatedIndexBitWidth =
2491 ConstantArrayType::getMaxSizeBits(SemaRef.Context);
2492 DesignatedStartIndex =
2493 DesignatedStartIndex.extOrTrunc(DesignatedIndexBitWidth);
2494 DesignatedEndIndex =
2495 DesignatedEndIndex.extOrTrunc(DesignatedIndexBitWidth);
2496 DesignatedStartIndex.setIsUnsigned(true);
2497 DesignatedEndIndex.setIsUnsigned(true);
2500 if (!VerifyOnly && StructuredList->isStringLiteralInit()) {
2501 // We're modifying a string literal init; we have to decompose the string
2502 // so we can modify the individual characters.
2503 ASTContext &Context = SemaRef.Context;
2504 Expr *SubExpr = StructuredList->getInit(0)->IgnoreParens();
2506 // Compute the character type
2507 QualType CharTy = AT->getElementType();
2509 // Compute the type of the integer literals.
2510 QualType PromotedCharTy = CharTy;
2511 if (CharTy->isPromotableIntegerType())
2512 PromotedCharTy = Context.getPromotedIntegerType(CharTy);
2513 unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy);
2515 if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) {
2516 // Get the length of the string.
2517 uint64_t StrLen = SL->getLength();
2518 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2519 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2520 StructuredList->resizeInits(Context, StrLen);
2522 // Build a literal for each character in the string, and put them into
2524 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2525 llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i));
2526 Expr *Init = new (Context) IntegerLiteral(
2527 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2528 if (CharTy != PromotedCharTy)
2529 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2530 Init, nullptr, VK_RValue);
2531 StructuredList->updateInit(Context, i, Init);
2534 ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr);
2536 Context.getObjCEncodingForType(E->getEncodedType(), Str);
2538 // Get the length of the string.
2539 uint64_t StrLen = Str.size();
2540 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2541 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2542 StructuredList->resizeInits(Context, StrLen);
2544 // Build a literal for each character in the string, and put them into
2546 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2547 llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]);
2548 Expr *Init = new (Context) IntegerLiteral(
2549 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2550 if (CharTy != PromotedCharTy)
2551 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2552 Init, nullptr, VK_RValue);
2553 StructuredList->updateInit(Context, i, Init);
2558 // Make sure that our non-designated initializer list has space
2559 // for a subobject corresponding to this array element.
2561 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits())
2562 StructuredList->resizeInits(SemaRef.Context,
2563 DesignatedEndIndex.getZExtValue() + 1);
2565 // Repeatedly perform subobject initializations in the range
2566 // [DesignatedStartIndex, DesignatedEndIndex].
2568 // Move to the next designator
2569 unsigned ElementIndex = DesignatedStartIndex.getZExtValue();
2570 unsigned OldIndex = Index;
2572 InitializedEntity ElementEntity =
2573 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
2575 while (DesignatedStartIndex <= DesignatedEndIndex) {
2576 // Recurse to check later designated subobjects.
2577 QualType ElementType = AT->getElementType();
2580 ElementEntity.setElementIndex(ElementIndex);
2581 if (CheckDesignatedInitializer(
2582 ElementEntity, IList, DIE, DesigIdx + 1, ElementType, nullptr,
2583 nullptr, Index, StructuredList, ElementIndex,
2584 FinishSubobjectInit && (DesignatedStartIndex == DesignatedEndIndex),
2588 // Move to the next index in the array that we'll be initializing.
2589 ++DesignatedStartIndex;
2590 ElementIndex = DesignatedStartIndex.getZExtValue();
2593 // If this the first designator, our caller will continue checking
2594 // the rest of this array subobject.
2595 if (IsFirstDesignator) {
2596 if (NextElementIndex)
2597 *NextElementIndex = DesignatedStartIndex;
2598 StructuredIndex = ElementIndex;
2602 if (!FinishSubobjectInit)
2605 // Check the remaining elements within this array subobject.
2606 bool prevHadError = hadError;
2607 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex,
2608 /*SubobjectIsDesignatorContext=*/false, Index,
2609 StructuredList, ElementIndex);
2610 return hadError && !prevHadError;
2613 // Get the structured initializer list for a subobject of type
2614 // @p CurrentObjectType.
2616 InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
2617 QualType CurrentObjectType,
2618 InitListExpr *StructuredList,
2619 unsigned StructuredIndex,
2620 SourceRange InitRange,
2621 bool IsFullyOverwritten) {
2623 return nullptr; // No structured list in verification-only mode.
2624 Expr *ExistingInit = nullptr;
2625 if (!StructuredList)
2626 ExistingInit = SyntacticToSemantic.lookup(IList);
2627 else if (StructuredIndex < StructuredList->getNumInits())
2628 ExistingInit = StructuredList->getInit(StructuredIndex);
2630 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit))
2631 // There might have already been initializers for subobjects of the current
2632 // object, but a subsequent initializer list will overwrite the entirety
2633 // of the current object. (See DR 253 and C99 6.7.8p21). e.g.,
2635 // struct P { char x[6]; };
2636 // struct P l = { .x[2] = 'x', .x = { [0] = 'f' } };
2638 // The first designated initializer is ignored, and l.x is just "f".
2639 if (!IsFullyOverwritten)
2643 // We are creating an initializer list that initializes the
2644 // subobjects of the current object, but there was already an
2645 // initialization that completely initialized the current
2646 // subobject, e.g., by a compound literal:
2648 // struct X { int a, b; };
2649 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2651 // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
2652 // designated initializer re-initializes the whole
2653 // subobject [0], overwriting previous initializers.
2654 SemaRef.Diag(InitRange.getBegin(),
2655 diag::warn_subobject_initializer_overrides)
2657 SemaRef.Diag(ExistingInit->getLocStart(),
2658 diag::note_previous_initializer)
2659 << /*FIXME:has side effects=*/0
2660 << ExistingInit->getSourceRange();
2663 InitListExpr *Result
2664 = new (SemaRef.Context) InitListExpr(SemaRef.Context,
2665 InitRange.getBegin(), None,
2666 InitRange.getEnd());
2668 QualType ResultType = CurrentObjectType;
2669 if (!ResultType->isArrayType())
2670 ResultType = ResultType.getNonLValueExprType(SemaRef.Context);
2671 Result->setType(ResultType);
2673 // Pre-allocate storage for the structured initializer list.
2674 unsigned NumElements = 0;
2675 unsigned NumInits = 0;
2676 bool GotNumInits = false;
2677 if (!StructuredList) {
2678 NumInits = IList->getNumInits();
2680 } else if (Index < IList->getNumInits()) {
2681 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) {
2682 NumInits = SubList->getNumInits();
2687 if (const ArrayType *AType
2688 = SemaRef.Context.getAsArrayType(CurrentObjectType)) {
2689 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) {
2690 NumElements = CAType->getSize().getZExtValue();
2691 // Simple heuristic so that we don't allocate a very large
2692 // initializer with many empty entries at the end.
2693 if (GotNumInits && NumElements > NumInits)
2696 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>())
2697 NumElements = VType->getNumElements();
2698 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) {
2699 RecordDecl *RDecl = RType->getDecl();
2700 if (RDecl->isUnion())
2703 NumElements = std::distance(RDecl->field_begin(), RDecl->field_end());
2706 Result->reserveInits(SemaRef.Context, NumElements);
2708 // Link this new initializer list into the structured initializer
2711 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result);
2713 Result->setSyntacticForm(IList);
2714 SyntacticToSemantic[IList] = Result;
2720 /// Update the initializer at index @p StructuredIndex within the
2721 /// structured initializer list to the value @p expr.
2722 void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList,
2723 unsigned &StructuredIndex,
2725 // No structured initializer list to update
2726 if (!StructuredList)
2729 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context,
2730 StructuredIndex, expr)) {
2731 // This initializer overwrites a previous initializer. Warn.
2732 // We need to check on source range validity because the previous
2733 // initializer does not have to be an explicit initializer.
2734 // struct P { int a, b; };
2735 // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
2736 // There is an overwrite taking place because the first braced initializer
2737 // list "{ .a = 2 }' already provides value for .p.b (which is zero).
2738 if (PrevInit->getSourceRange().isValid()) {
2739 SemaRef.Diag(expr->getLocStart(),
2740 diag::warn_initializer_overrides)
2741 << expr->getSourceRange();
2743 SemaRef.Diag(PrevInit->getLocStart(),
2744 diag::note_previous_initializer)
2745 << /*FIXME:has side effects=*/0
2746 << PrevInit->getSourceRange();
2753 /// Check that the given Index expression is a valid array designator
2754 /// value. This is essentially just a wrapper around
2755 /// VerifyIntegerConstantExpression that also checks for negative values
2756 /// and produces a reasonable diagnostic if there is a
2757 /// failure. Returns the index expression, possibly with an implicit cast
2758 /// added, on success. If everything went okay, Value will receive the
2759 /// value of the constant expression.
2761 CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) {
2762 SourceLocation Loc = Index->getLocStart();
2764 // Make sure this is an integer constant expression.
2765 ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value);
2766 if (Result.isInvalid())
2769 if (Value.isSigned() && Value.isNegative())
2770 return S.Diag(Loc, diag::err_array_designator_negative)
2771 << Value.toString(10) << Index->getSourceRange();
2773 Value.setIsUnsigned(true);
2777 ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig,
2781 typedef DesignatedInitExpr::Designator ASTDesignator;
2783 bool Invalid = false;
2784 SmallVector<ASTDesignator, 32> Designators;
2785 SmallVector<Expr *, 32> InitExpressions;
2787 // Build designators and check array designator expressions.
2788 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) {
2789 const Designator &D = Desig.getDesignator(Idx);
2790 switch (D.getKind()) {
2791 case Designator::FieldDesignator:
2792 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(),
2796 case Designator::ArrayDesignator: {
2797 Expr *Index = static_cast<Expr *>(D.getArrayIndex());
2798 llvm::APSInt IndexValue;
2799 if (!Index->isTypeDependent() && !Index->isValueDependent())
2800 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).get();
2804 Designators.push_back(ASTDesignator(InitExpressions.size(),
2806 D.getRBracketLoc()));
2807 InitExpressions.push_back(Index);
2812 case Designator::ArrayRangeDesignator: {
2813 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart());
2814 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd());
2815 llvm::APSInt StartValue;
2816 llvm::APSInt EndValue;
2817 bool StartDependent = StartIndex->isTypeDependent() ||
2818 StartIndex->isValueDependent();
2819 bool EndDependent = EndIndex->isTypeDependent() ||
2820 EndIndex->isValueDependent();
2821 if (!StartDependent)
2823 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).get();
2825 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).get();
2827 if (!StartIndex || !EndIndex)
2830 // Make sure we're comparing values with the same bit width.
2831 if (StartDependent || EndDependent) {
2832 // Nothing to compute.
2833 } else if (StartValue.getBitWidth() > EndValue.getBitWidth())
2834 EndValue = EndValue.extend(StartValue.getBitWidth());
2835 else if (StartValue.getBitWidth() < EndValue.getBitWidth())
2836 StartValue = StartValue.extend(EndValue.getBitWidth());
2838 if (!StartDependent && !EndDependent && EndValue < StartValue) {
2839 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range)
2840 << StartValue.toString(10) << EndValue.toString(10)
2841 << StartIndex->getSourceRange() << EndIndex->getSourceRange();
2844 Designators.push_back(ASTDesignator(InitExpressions.size(),
2847 D.getRBracketLoc()));
2848 InitExpressions.push_back(StartIndex);
2849 InitExpressions.push_back(EndIndex);
2857 if (Invalid || Init.isInvalid())
2860 // Clear out the expressions within the designation.
2861 Desig.ClearExprs(*this);
2863 DesignatedInitExpr *DIE
2864 = DesignatedInitExpr::Create(Context,
2866 InitExpressions, Loc, GNUSyntax,
2867 Init.getAs<Expr>());
2869 if (!getLangOpts().C99)
2870 Diag(DIE->getLocStart(), diag::ext_designated_init)
2871 << DIE->getSourceRange();
2876 //===----------------------------------------------------------------------===//
2877 // Initialization entity
2878 //===----------------------------------------------------------------------===//
2880 InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index,
2881 const InitializedEntity &Parent)
2882 : Parent(&Parent), Index(Index)
2884 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) {
2885 Kind = EK_ArrayElement;
2886 Type = AT->getElementType();
2887 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) {
2888 Kind = EK_VectorElement;
2889 Type = VT->getElementType();
2891 const ComplexType *CT = Parent.getType()->getAs<ComplexType>();
2892 assert(CT && "Unexpected type");
2893 Kind = EK_ComplexElement;
2894 Type = CT->getElementType();
2899 InitializedEntity::InitializeBase(ASTContext &Context,
2900 const CXXBaseSpecifier *Base,
2901 bool IsInheritedVirtualBase,
2902 const InitializedEntity *Parent) {
2903 InitializedEntity Result;
2904 Result.Kind = EK_Base;
2905 Result.Parent = Parent;
2906 Result.Base = reinterpret_cast<uintptr_t>(Base);
2907 if (IsInheritedVirtualBase)
2908 Result.Base |= 0x01;
2910 Result.Type = Base->getType();
2914 DeclarationName InitializedEntity::getName() const {
2915 switch (getKind()) {
2917 case EK_Parameter_CF_Audited: {
2918 ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
2919 return (D ? D->getDeclName() : DeclarationName());
2925 return Variable.VariableOrMember->getDeclName();
2927 case EK_LambdaCapture:
2928 return DeclarationName(Capture.VarID);
2936 case EK_ArrayElement:
2937 case EK_VectorElement:
2938 case EK_ComplexElement:
2939 case EK_BlockElement:
2940 case EK_LambdaToBlockConversionBlockElement:
2941 case EK_CompoundLiteralInit:
2942 case EK_RelatedResult:
2943 return DeclarationName();
2946 llvm_unreachable("Invalid EntityKind!");
2949 ValueDecl *InitializedEntity::getDecl() const {
2950 switch (getKind()) {
2954 return Variable.VariableOrMember;
2957 case EK_Parameter_CF_Audited:
2958 return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
2966 case EK_ArrayElement:
2967 case EK_VectorElement:
2968 case EK_ComplexElement:
2969 case EK_BlockElement:
2970 case EK_LambdaToBlockConversionBlockElement:
2971 case EK_LambdaCapture:
2972 case EK_CompoundLiteralInit:
2973 case EK_RelatedResult:
2977 llvm_unreachable("Invalid EntityKind!");
2980 bool InitializedEntity::allowsNRVO() const {
2981 switch (getKind()) {
2984 return LocAndNRVO.NRVO;
2988 case EK_Parameter_CF_Audited:
2993 case EK_CompoundLiteralInit:
2996 case EK_ArrayElement:
2997 case EK_VectorElement:
2998 case EK_ComplexElement:
2999 case EK_BlockElement:
3000 case EK_LambdaToBlockConversionBlockElement:
3001 case EK_LambdaCapture:
3002 case EK_RelatedResult:
3009 unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const {
3010 assert(getParent() != this);
3011 unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0;
3012 for (unsigned I = 0; I != Depth; ++I)
3015 switch (getKind()) {
3016 case EK_Variable: OS << "Variable"; break;
3017 case EK_Parameter: OS << "Parameter"; break;
3018 case EK_Parameter_CF_Audited: OS << "CF audited function Parameter";
3020 case EK_Result: OS << "Result"; break;
3021 case EK_Exception: OS << "Exception"; break;
3022 case EK_Member: OS << "Member"; break;
3023 case EK_Binding: OS << "Binding"; break;
3024 case EK_New: OS << "New"; break;
3025 case EK_Temporary: OS << "Temporary"; break;
3026 case EK_CompoundLiteralInit: OS << "CompoundLiteral";break;
3027 case EK_RelatedResult: OS << "RelatedResult"; break;
3028 case EK_Base: OS << "Base"; break;
3029 case EK_Delegating: OS << "Delegating"; break;
3030 case EK_ArrayElement: OS << "ArrayElement " << Index; break;
3031 case EK_VectorElement: OS << "VectorElement " << Index; break;
3032 case EK_ComplexElement: OS << "ComplexElement " << Index; break;
3033 case EK_BlockElement: OS << "Block"; break;
3034 case EK_LambdaToBlockConversionBlockElement:
3035 OS << "Block (lambda)";
3037 case EK_LambdaCapture:
3038 OS << "LambdaCapture ";
3039 OS << DeclarationName(Capture.VarID);
3043 if (auto *D = getDecl()) {
3045 D->printQualifiedName(OS);
3048 OS << " '" << getType().getAsString() << "'\n";
3053 LLVM_DUMP_METHOD void InitializedEntity::dump() const {
3054 dumpImpl(llvm::errs());
3057 //===----------------------------------------------------------------------===//
3058 // Initialization sequence
3059 //===----------------------------------------------------------------------===//
3061 void InitializationSequence::Step::Destroy() {
3063 case SK_ResolveAddressOfOverloadedFunction:
3064 case SK_CastDerivedToBaseRValue:
3065 case SK_CastDerivedToBaseXValue:
3066 case SK_CastDerivedToBaseLValue:
3067 case SK_BindReference:
3068 case SK_BindReferenceToTemporary:
3070 case SK_ExtraneousCopyToTemporary:
3071 case SK_UserConversion:
3072 case SK_QualificationConversionRValue:
3073 case SK_QualificationConversionXValue:
3074 case SK_QualificationConversionLValue:
3075 case SK_AtomicConversion:
3076 case SK_LValueToRValue:
3077 case SK_ListInitialization:
3078 case SK_UnwrapInitList:
3079 case SK_RewrapInitList:
3080 case SK_ConstructorInitialization:
3081 case SK_ConstructorInitializationFromList:
3082 case SK_ZeroInitialization:
3083 case SK_CAssignment:
3085 case SK_ObjCObjectConversion:
3086 case SK_ArrayLoopIndex:
3087 case SK_ArrayLoopInit:
3089 case SK_GNUArrayInit:
3090 case SK_ParenthesizedArrayInit:
3091 case SK_PassByIndirectCopyRestore:
3092 case SK_PassByIndirectRestore:
3093 case SK_ProduceObjCObject:
3094 case SK_StdInitializerList:
3095 case SK_StdInitializerListConstructorCall:
3096 case SK_OCLSamplerInit:
3097 case SK_OCLZeroEvent:
3098 case SK_OCLZeroQueue:
3101 case SK_ConversionSequence:
3102 case SK_ConversionSequenceNoNarrowing:
3107 bool InitializationSequence::isDirectReferenceBinding() const {
3108 // There can be some lvalue adjustments after the SK_BindReference step.
3109 for (auto I = Steps.rbegin(); I != Steps.rend(); ++I) {
3110 if (I->Kind == SK_BindReference)
3112 if (I->Kind == SK_BindReferenceToTemporary)
3118 bool InitializationSequence::isAmbiguous() const {
3122 switch (getFailureKind()) {
3123 case FK_TooManyInitsForReference:
3124 case FK_ParenthesizedListInitForReference:
3125 case FK_ArrayNeedsInitList:
3126 case FK_ArrayNeedsInitListOrStringLiteral:
3127 case FK_ArrayNeedsInitListOrWideStringLiteral:
3128 case FK_NarrowStringIntoWideCharArray:
3129 case FK_WideStringIntoCharArray:
3130 case FK_IncompatWideStringIntoWideChar:
3131 case FK_AddressOfOverloadFailed: // FIXME: Could do better
3132 case FK_NonConstLValueReferenceBindingToTemporary:
3133 case FK_NonConstLValueReferenceBindingToBitfield:
3134 case FK_NonConstLValueReferenceBindingToVectorElement:
3135 case FK_NonConstLValueReferenceBindingToUnrelated:
3136 case FK_RValueReferenceBindingToLValue:
3137 case FK_ReferenceInitDropsQualifiers:
3138 case FK_ReferenceInitFailed:
3139 case FK_ConversionFailed:
3140 case FK_ConversionFromPropertyFailed:
3141 case FK_TooManyInitsForScalar:
3142 case FK_ParenthesizedListInitForScalar:
3143 case FK_ReferenceBindingToInitList:
3144 case FK_InitListBadDestinationType:
3145 case FK_DefaultInitOfConst:
3147 case FK_ArrayTypeMismatch:
3148 case FK_NonConstantArrayInit:
3149 case FK_ListInitializationFailed:
3150 case FK_VariableLengthArrayHasInitializer:
3151 case FK_PlaceholderType:
3152 case FK_ExplicitConstructor:
3153 case FK_AddressOfUnaddressableFunction:
3156 case FK_ReferenceInitOverloadFailed:
3157 case FK_UserConversionOverloadFailed:
3158 case FK_ConstructorOverloadFailed:
3159 case FK_ListConstructorOverloadFailed:
3160 return FailedOverloadResult == OR_Ambiguous;
3163 llvm_unreachable("Invalid EntityKind!");
3166 bool InitializationSequence::isConstructorInitialization() const {
3167 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization;
3171 InitializationSequence
3172 ::AddAddressOverloadResolutionStep(FunctionDecl *Function,
3173 DeclAccessPair Found,
3174 bool HadMultipleCandidates) {
3176 S.Kind = SK_ResolveAddressOfOverloadedFunction;
3177 S.Type = Function->getType();
3178 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3179 S.Function.Function = Function;
3180 S.Function.FoundDecl = Found;
3184 void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType,
3188 case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break;
3189 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break;
3190 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break;
3196 void InitializationSequence::AddReferenceBindingStep(QualType T,
3197 bool BindingTemporary) {
3199 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference;
3204 void InitializationSequence::AddFinalCopy(QualType T) {
3206 S.Kind = SK_FinalCopy;
3211 void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) {
3213 S.Kind = SK_ExtraneousCopyToTemporary;
3219 InitializationSequence::AddUserConversionStep(FunctionDecl *Function,
3220 DeclAccessPair FoundDecl,
3222 bool HadMultipleCandidates) {
3224 S.Kind = SK_UserConversion;
3226 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3227 S.Function.Function = Function;
3228 S.Function.FoundDecl = FoundDecl;
3232 void InitializationSequence::AddQualificationConversionStep(QualType Ty,
3235 S.Kind = SK_QualificationConversionRValue; // work around a gcc warning
3238 S.Kind = SK_QualificationConversionRValue;
3241 S.Kind = SK_QualificationConversionXValue;
3244 S.Kind = SK_QualificationConversionLValue;
3251 void InitializationSequence::AddAtomicConversionStep(QualType Ty) {
3253 S.Kind = SK_AtomicConversion;
3258 void InitializationSequence::AddLValueToRValueStep(QualType Ty) {
3259 assert(!Ty.hasQualifiers() && "rvalues may not have qualifiers");
3262 S.Kind = SK_LValueToRValue;
3267 void InitializationSequence::AddConversionSequenceStep(
3268 const ImplicitConversionSequence &ICS, QualType T,
3269 bool TopLevelOfInitList) {
3271 S.Kind = TopLevelOfInitList ? SK_ConversionSequenceNoNarrowing
3272 : SK_ConversionSequence;
3274 S.ICS = new ImplicitConversionSequence(ICS);
3278 void InitializationSequence::AddListInitializationStep(QualType T) {
3280 S.Kind = SK_ListInitialization;
3285 void InitializationSequence::AddConstructorInitializationStep(
3286 DeclAccessPair FoundDecl, CXXConstructorDecl *Constructor, QualType T,
3287 bool HadMultipleCandidates, bool FromInitList, bool AsInitList) {
3289 S.Kind = FromInitList ? AsInitList ? SK_StdInitializerListConstructorCall
3290 : SK_ConstructorInitializationFromList
3291 : SK_ConstructorInitialization;
3293 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3294 S.Function.Function = Constructor;
3295 S.Function.FoundDecl = FoundDecl;
3299 void InitializationSequence::AddZeroInitializationStep(QualType T) {
3301 S.Kind = SK_ZeroInitialization;
3306 void InitializationSequence::AddCAssignmentStep(QualType T) {
3308 S.Kind = SK_CAssignment;
3313 void InitializationSequence::AddStringInitStep(QualType T) {
3315 S.Kind = SK_StringInit;
3320 void InitializationSequence::AddObjCObjectConversionStep(QualType T) {
3322 S.Kind = SK_ObjCObjectConversion;
3327 void InitializationSequence::AddArrayInitStep(QualType T, bool IsGNUExtension) {
3329 S.Kind = IsGNUExtension ? SK_GNUArrayInit : SK_ArrayInit;
3334 void InitializationSequence::AddArrayInitLoopStep(QualType T, QualType EltT) {
3336 S.Kind = SK_ArrayLoopIndex;
3338 Steps.insert(Steps.begin(), S);
3340 S.Kind = SK_ArrayLoopInit;
3345 void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) {
3347 S.Kind = SK_ParenthesizedArrayInit;
3352 void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type,
3355 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore
3356 : SK_PassByIndirectRestore);
3361 void InitializationSequence::AddProduceObjCObjectStep(QualType T) {
3363 S.Kind = SK_ProduceObjCObject;
3368 void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
3370 S.Kind = SK_StdInitializerList;
3375 void InitializationSequence::AddOCLSamplerInitStep(QualType T) {
3377 S.Kind = SK_OCLSamplerInit;
3382 void InitializationSequence::AddOCLZeroEventStep(QualType T) {
3384 S.Kind = SK_OCLZeroEvent;
3389 void InitializationSequence::AddOCLZeroQueueStep(QualType T) {
3391 S.Kind = SK_OCLZeroQueue;
3396 void InitializationSequence::RewrapReferenceInitList(QualType T,
3397 InitListExpr *Syntactic) {
3398 assert(Syntactic->getNumInits() == 1 &&
3399 "Can only rewrap trivial init lists.");
3401 S.Kind = SK_UnwrapInitList;
3402 S.Type = Syntactic->getInit(0)->getType();
3403 Steps.insert(Steps.begin(), S);
3405 S.Kind = SK_RewrapInitList;
3407 S.WrappingSyntacticList = Syntactic;
3411 void InitializationSequence::SetOverloadFailure(FailureKind Failure,
3412 OverloadingResult Result) {
3413 setSequenceKind(FailedSequence);
3414 this->Failure = Failure;
3415 this->FailedOverloadResult = Result;
3418 //===----------------------------------------------------------------------===//
3419 // Attempt initialization
3420 //===----------------------------------------------------------------------===//
3422 /// Tries to add a zero initializer. Returns true if that worked.
3424 maybeRecoverWithZeroInitialization(Sema &S, InitializationSequence &Sequence,
3425 const InitializedEntity &Entity) {
3426 if (Entity.getKind() != InitializedEntity::EK_Variable)
3429 VarDecl *VD = cast<VarDecl>(Entity.getDecl());
3430 if (VD->getInit() || VD->getLocEnd().isMacroID())
3433 QualType VariableTy = VD->getType().getCanonicalType();
3434 SourceLocation Loc = S.getLocForEndOfToken(VD->getLocEnd());
3435 std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
3436 if (!Init.empty()) {
3437 Sequence.AddZeroInitializationStep(Entity.getType());
3438 Sequence.SetZeroInitializationFixit(Init, Loc);
3444 static void MaybeProduceObjCObject(Sema &S,
3445 InitializationSequence &Sequence,
3446 const InitializedEntity &Entity) {
3447 if (!S.getLangOpts().ObjCAutoRefCount) return;
3449 /// When initializing a parameter, produce the value if it's marked
3450 /// __attribute__((ns_consumed)).
3451 if (Entity.isParameterKind()) {
3452 if (!Entity.isParameterConsumed())
3455 assert(Entity.getType()->isObjCRetainableType() &&
3456 "consuming an object of unretainable type?");
3457 Sequence.AddProduceObjCObjectStep(Entity.getType());
3459 /// When initializing a return value, if the return type is a
3460 /// retainable type, then returns need to immediately retain the
3461 /// object. If an autorelease is required, it will be done at the
3463 } else if (Entity.getKind() == InitializedEntity::EK_Result) {
3464 if (!Entity.getType()->isObjCRetainableType())
3467 Sequence.AddProduceObjCObjectStep(Entity.getType());
3471 static void TryListInitialization(Sema &S,
3472 const InitializedEntity &Entity,
3473 const InitializationKind &Kind,
3474 InitListExpr *InitList,
3475 InitializationSequence &Sequence,
3476 bool TreatUnavailableAsInvalid);
3478 /// \brief When initializing from init list via constructor, handle
3479 /// initialization of an object of type std::initializer_list<T>.
3481 /// \return true if we have handled initialization of an object of type
3482 /// std::initializer_list<T>, false otherwise.
3483 static bool TryInitializerListConstruction(Sema &S,
3486 InitializationSequence &Sequence,
3487 bool TreatUnavailableAsInvalid) {
3489 if (!S.isStdInitializerList(DestType, &E))
3492 if (!S.isCompleteType(List->getExprLoc(), E)) {
3493 Sequence.setIncompleteTypeFailure(E);
3497 // Try initializing a temporary array from the init list.
3498 QualType ArrayType = S.Context.getConstantArrayType(
3499 E.withConst(), llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
3500 List->getNumInits()),
3501 clang::ArrayType::Normal, 0);
3502 InitializedEntity HiddenArray =
3503 InitializedEntity::InitializeTemporary(ArrayType);
3504 InitializationKind Kind =
3505 InitializationKind::CreateDirectList(List->getExprLoc());
3506 TryListInitialization(S, HiddenArray, Kind, List, Sequence,
3507 TreatUnavailableAsInvalid);
3509 Sequence.AddStdInitializerListConstructionStep(DestType);
3513 /// Determine if the constructor has the signature of a copy or move
3514 /// constructor for the type T of the class in which it was found. That is,
3515 /// determine if its first parameter is of type T or reference to (possibly
3516 /// cv-qualified) T.
3517 static bool hasCopyOrMoveCtorParam(ASTContext &Ctx,
3518 const ConstructorInfo &Info) {
3519 if (Info.Constructor->getNumParams() == 0)
3523 Info.Constructor->getParamDecl(0)->getType().getNonReferenceType();
3525 Ctx.getRecordType(cast<CXXRecordDecl>(Info.FoundDecl->getDeclContext()));
3527 return Ctx.hasSameUnqualifiedType(ParmT, ClassT);
3530 static OverloadingResult
3531 ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc,
3533 OverloadCandidateSet &CandidateSet,
3534 DeclContext::lookup_result Ctors,
3535 OverloadCandidateSet::iterator &Best,
3536 bool CopyInitializing, bool AllowExplicit,
3537 bool OnlyListConstructors, bool IsListInit,
3538 bool SecondStepOfCopyInit = false) {
3539 CandidateSet.clear();
3541 for (NamedDecl *D : Ctors) {
3542 auto Info = getConstructorInfo(D);
3543 if (!Info.Constructor || Info.Constructor->isInvalidDecl())
3546 if (!AllowExplicit && Info.Constructor->isExplicit())
3549 if (OnlyListConstructors && !S.isInitListConstructor(Info.Constructor))
3552 // C++11 [over.best.ics]p4:
3553 // ... and the constructor or user-defined conversion function is a
3555 // - 13.3.1.3, when the argument is the temporary in the second step
3556 // of a class copy-initialization, or
3557 // - 13.3.1.4, 13.3.1.5, or 13.3.1.6 (in all cases), [not handled here]
3558 // - the second phase of 13.3.1.7 when the initializer list has exactly
3559 // one element that is itself an initializer list, and the target is
3560 // the first parameter of a constructor of class X, and the conversion
3561 // is to X or reference to (possibly cv-qualified X),
3562 // user-defined conversion sequences are not considered.
3563 bool SuppressUserConversions =
3564 SecondStepOfCopyInit ||
3565 (IsListInit && Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
3566 hasCopyOrMoveCtorParam(S.Context, Info));
3568 if (Info.ConstructorTmpl)
3569 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
3570 /*ExplicitArgs*/ nullptr, Args,
3571 CandidateSet, SuppressUserConversions);
3573 // C++ [over.match.copy]p1:
3574 // - When initializing a temporary to be bound to the first parameter
3575 // of a constructor [for type T] that takes a reference to possibly
3576 // cv-qualified T as its first argument, called with a single
3577 // argument in the context of direct-initialization, explicit
3578 // conversion functions are also considered.
3579 // FIXME: What if a constructor template instantiates to such a signature?
3580 bool AllowExplicitConv = AllowExplicit && !CopyInitializing &&
3582 hasCopyOrMoveCtorParam(S.Context, Info);
3583 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, Args,
3584 CandidateSet, SuppressUserConversions,
3585 /*PartialOverloading=*/false,
3586 /*AllowExplicit=*/AllowExplicitConv);
3590 // Perform overload resolution and return the result.
3591 return CandidateSet.BestViableFunction(S, DeclLoc, Best);
3594 /// \brief Attempt initialization by constructor (C++ [dcl.init]), which
3595 /// enumerates the constructors of the initialized entity and performs overload
3596 /// resolution to select the best.
3597 /// \param DestType The destination class type.
3598 /// \param DestArrayType The destination type, which is either DestType or
3599 /// a (possibly multidimensional) array of DestType.
3600 /// \param IsListInit Is this list-initialization?
3601 /// \param IsInitListCopy Is this non-list-initialization resulting from a
3602 /// list-initialization from {x} where x is the same
3603 /// type as the entity?
3604 static void TryConstructorInitialization(Sema &S,
3605 const InitializedEntity &Entity,
3606 const InitializationKind &Kind,
3607 MultiExprArg Args, QualType DestType,
3608 QualType DestArrayType,
3609 InitializationSequence &Sequence,
3610 bool IsListInit = false,
3611 bool IsInitListCopy = false) {
3612 assert(((!IsListInit && !IsInitListCopy) ||
3613 (Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&
3614 "IsListInit/IsInitListCopy must come with a single initializer list "
3617 (IsListInit || IsInitListCopy) ? cast<InitListExpr>(Args[0]) : nullptr;
3618 MultiExprArg UnwrappedArgs =
3619 ILE ? MultiExprArg(ILE->getInits(), ILE->getNumInits()) : Args;
3621 // The type we're constructing needs to be complete.
3622 if (!S.isCompleteType(Kind.getLocation(), DestType)) {
3623 Sequence.setIncompleteTypeFailure(DestType);
3627 // C++1z [dcl.init]p17:
3628 // - If the initializer expression is a prvalue and the cv-unqualified
3629 // version of the source type is the same class as the class of the
3630 // destination, the initializer expression is used to initialize the
3631 // destination object.
3632 // Per DR (no number yet), this does not apply when initializing a base
3633 // class or delegating to another constructor from a mem-initializer.
3634 // ObjC++: Lambda captured by the block in the lambda to block conversion
3635 // should avoid copy elision.
3636 if (S.getLangOpts().CPlusPlus1z &&
3637 Entity.getKind() != InitializedEntity::EK_Base &&
3638 Entity.getKind() != InitializedEntity::EK_Delegating &&
3640 InitializedEntity::EK_LambdaToBlockConversionBlockElement &&
3641 UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isRValue() &&
3642 S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) {
3643 // Convert qualifications if necessary.
3644 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
3646 Sequence.RewrapReferenceInitList(DestType, ILE);
3650 const RecordType *DestRecordType = DestType->getAs<RecordType>();
3651 assert(DestRecordType && "Constructor initialization requires record type");
3652 CXXRecordDecl *DestRecordDecl
3653 = cast<CXXRecordDecl>(DestRecordType->getDecl());
3655 // Build the candidate set directly in the initialization sequence
3656 // structure, so that it will persist if we fail.
3657 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
3659 // Determine whether we are allowed to call explicit constructors or
3660 // explicit conversion operators.
3661 bool AllowExplicit = Kind.AllowExplicit() || IsListInit;
3662 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy;
3664 // - Otherwise, if T is a class type, constructors are considered. The
3665 // applicable constructors are enumerated, and the best one is chosen
3666 // through overload resolution.
3667 DeclContext::lookup_result Ctors = S.LookupConstructors(DestRecordDecl);
3669 OverloadingResult Result = OR_No_Viable_Function;
3670 OverloadCandidateSet::iterator Best;
3671 bool AsInitializerList = false;
3673 // C++11 [over.match.list]p1, per DR1467:
3674 // When objects of non-aggregate type T are list-initialized, such that
3675 // 8.5.4 [dcl.init.list] specifies that overload resolution is performed
3676 // according to the rules in this section, overload resolution selects
3677 // the constructor in two phases:
3679 // - Initially, the candidate functions are the initializer-list
3680 // constructors of the class T and the argument list consists of the
3681 // initializer list as a single argument.
3683 AsInitializerList = true;
3685 // If the initializer list has no elements and T has a default constructor,
3686 // the first phase is omitted.
3687 if (!(UnwrappedArgs.empty() && DestRecordDecl->hasDefaultConstructor()))
3688 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
3689 CandidateSet, Ctors, Best,
3690 CopyInitialization, AllowExplicit,
3691 /*OnlyListConstructor=*/true,
3695 // C++11 [over.match.list]p1:
3696 // - If no viable initializer-list constructor is found, overload resolution
3697 // is performed again, where the candidate functions are all the
3698 // constructors of the class T and the argument list consists of the
3699 // elements of the initializer list.
3700 if (Result == OR_No_Viable_Function) {
3701 AsInitializerList = false;
3702 Result = ResolveConstructorOverload(S, Kind.getLocation(), UnwrappedArgs,
3703 CandidateSet, Ctors, Best,
3704 CopyInitialization, AllowExplicit,
3705 /*OnlyListConstructors=*/false,
3709 Sequence.SetOverloadFailure(IsListInit ?
3710 InitializationSequence::FK_ListConstructorOverloadFailed :
3711 InitializationSequence::FK_ConstructorOverloadFailed,
3716 // C++11 [dcl.init]p6:
3717 // If a program calls for the default initialization of an object
3718 // of a const-qualified type T, T shall be a class type with a
3719 // user-provided default constructor.
3720 // C++ core issue 253 proposal:
3721 // If the implicit default constructor initializes all subobjects, no
3722 // initializer should be required.
3723 // The 253 proposal is for example needed to process libstdc++ headers in 5.x.
3724 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
3725 if (Kind.getKind() == InitializationKind::IK_Default &&
3726 Entity.getType().isConstQualified()) {
3727 if (!CtorDecl->getParent()->allowConstDefaultInit()) {
3728 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
3729 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
3734 // C++11 [over.match.list]p1:
3735 // In copy-list-initialization, if an explicit constructor is chosen, the
3736 // initializer is ill-formed.
3737 if (IsListInit && !Kind.AllowExplicit() && CtorDecl->isExplicit()) {
3738 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor);
3742 // Add the constructor initialization step. Any cv-qualification conversion is
3743 // subsumed by the initialization.
3744 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3745 Sequence.AddConstructorInitializationStep(
3746 Best->FoundDecl, CtorDecl, DestArrayType, HadMultipleCandidates,
3747 IsListInit | IsInitListCopy, AsInitializerList);
3751 ResolveOverloadedFunctionForReferenceBinding(Sema &S,
3753 QualType &SourceType,
3754 QualType &UnqualifiedSourceType,
3755 QualType UnqualifiedTargetType,
3756 InitializationSequence &Sequence) {
3757 if (S.Context.getCanonicalType(UnqualifiedSourceType) ==
3758 S.Context.OverloadTy) {
3759 DeclAccessPair Found;
3760 bool HadMultipleCandidates = false;
3761 if (FunctionDecl *Fn
3762 = S.ResolveAddressOfOverloadedFunction(Initializer,
3763 UnqualifiedTargetType,
3765 &HadMultipleCandidates)) {
3766 Sequence.AddAddressOverloadResolutionStep(Fn, Found,
3767 HadMultipleCandidates);
3768 SourceType = Fn->getType();
3769 UnqualifiedSourceType = SourceType.getUnqualifiedType();
3770 } else if (!UnqualifiedTargetType->isRecordType()) {
3771 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
3778 static void TryReferenceInitializationCore(Sema &S,
3779 const InitializedEntity &Entity,
3780 const InitializationKind &Kind,
3782 QualType cv1T1, QualType T1,
3784 QualType cv2T2, QualType T2,
3786 InitializationSequence &Sequence);
3788 static void TryValueInitialization(Sema &S,
3789 const InitializedEntity &Entity,
3790 const InitializationKind &Kind,
3791 InitializationSequence &Sequence,
3792 InitListExpr *InitList = nullptr);
3794 /// \brief Attempt list initialization of a reference.
3795 static void TryReferenceListInitialization(Sema &S,
3796 const InitializedEntity &Entity,
3797 const InitializationKind &Kind,
3798 InitListExpr *InitList,
3799 InitializationSequence &Sequence,
3800 bool TreatUnavailableAsInvalid) {
3801 // First, catch C++03 where this isn't possible.
3802 if (!S.getLangOpts().CPlusPlus11) {
3803 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
3806 // Can't reference initialize a compound literal.
3807 if (Entity.getKind() == InitializedEntity::EK_CompoundLiteralInit) {
3808 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
3812 QualType DestType = Entity.getType();
3813 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
3815 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
3817 // Reference initialization via an initializer list works thus:
3818 // If the initializer list consists of a single element that is
3819 // reference-related to the referenced type, bind directly to that element
3820 // (possibly creating temporaries).
3821 // Otherwise, initialize a temporary with the initializer list and
3823 if (InitList->getNumInits() == 1) {
3824 Expr *Initializer = InitList->getInit(0);
3825 QualType cv2T2 = Initializer->getType();
3827 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
3829 // If this fails, creating a temporary wouldn't work either.
3830 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
3834 SourceLocation DeclLoc = Initializer->getLocStart();
3835 bool dummy1, dummy2, dummy3;
3836 Sema::ReferenceCompareResult RefRelationship
3837 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1,
3839 if (RefRelationship >= Sema::Ref_Related) {
3840 // Try to bind the reference here.
3841 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
3842 T1Quals, cv2T2, T2, T2Quals, Sequence);
3844 Sequence.RewrapReferenceInitList(cv1T1, InitList);
3848 // Update the initializer if we've resolved an overloaded function.
3849 if (Sequence.step_begin() != Sequence.step_end())
3850 Sequence.RewrapReferenceInitList(cv1T1, InitList);
3853 // Not reference-related. Create a temporary and bind to that.
3854 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
3856 TryListInitialization(S, TempEntity, Kind, InitList, Sequence,
3857 TreatUnavailableAsInvalid);
3859 if (DestType->isRValueReferenceType() ||
3860 (T1Quals.hasConst() && !T1Quals.hasVolatile()))
3861 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
3864 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
3868 /// \brief Attempt list initialization (C++0x [dcl.init.list])
3869 static void TryListInitialization(Sema &S,
3870 const InitializedEntity &Entity,
3871 const InitializationKind &Kind,
3872 InitListExpr *InitList,
3873 InitializationSequence &Sequence,
3874 bool TreatUnavailableAsInvalid) {
3875 QualType DestType = Entity.getType();
3877 // C++ doesn't allow scalar initialization with more than one argument.
3878 // But C99 complex numbers are scalars and it makes sense there.
3879 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() &&
3880 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) {
3881 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar);
3884 if (DestType->isReferenceType()) {
3885 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence,
3886 TreatUnavailableAsInvalid);
3890 if (DestType->isRecordType() &&
3891 !S.isCompleteType(InitList->getLocStart(), DestType)) {
3892 Sequence.setIncompleteTypeFailure(DestType);
3896 // C++11 [dcl.init.list]p3, per DR1467:
3897 // - If T is a class type and the initializer list has a single element of
3898 // type cv U, where U is T or a class derived from T, the object is
3899 // initialized from that element (by copy-initialization for
3900 // copy-list-initialization, or by direct-initialization for
3901 // direct-list-initialization).
3902 // - Otherwise, if T is a character array and the initializer list has a
3903 // single element that is an appropriately-typed string literal
3904 // (8.5.2 [dcl.init.string]), initialization is performed as described
3906 // - Otherwise, if T is an aggregate, [...] (continue below).
3907 if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1) {
3908 if (DestType->isRecordType()) {
3909 QualType InitType = InitList->getInit(0)->getType();
3910 if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
3911 S.IsDerivedFrom(InitList->getLocStart(), InitType, DestType)) {
3912 Expr *InitListAsExpr = InitList;
3913 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
3915 /*InitListSyntax*/false,
3916 /*IsInitListCopy*/true);
3920 if (const ArrayType *DestAT = S.Context.getAsArrayType(DestType)) {
3921 Expr *SubInit[1] = {InitList->getInit(0)};
3922 if (!isa<VariableArrayType>(DestAT) &&
3923 IsStringInit(SubInit[0], DestAT, S.Context) == SIF_None) {
3924 InitializationKind SubKind =
3925 Kind.getKind() == InitializationKind::IK_DirectList
3926 ? InitializationKind::CreateDirect(Kind.getLocation(),
3927 InitList->getLBraceLoc(),
3928 InitList->getRBraceLoc())
3930 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
3931 /*TopLevelOfInitList*/ true,
3932 TreatUnavailableAsInvalid);
3934 // TryStringLiteralInitialization() (in InitializeFrom()) will fail if
3935 // the element is not an appropriately-typed string literal, in which
3936 // case we should proceed as in C++11 (below).
3938 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
3945 // C++11 [dcl.init.list]p3:
3946 // - If T is an aggregate, aggregate initialization is performed.
3947 if ((DestType->isRecordType() && !DestType->isAggregateType()) ||
3948 (S.getLangOpts().CPlusPlus11 &&
3949 S.isStdInitializerList(DestType, nullptr))) {
3950 if (S.getLangOpts().CPlusPlus11) {
3951 // - Otherwise, if the initializer list has no elements and T is a
3952 // class type with a default constructor, the object is
3953 // value-initialized.
3954 if (InitList->getNumInits() == 0) {
3955 CXXRecordDecl *RD = DestType->getAsCXXRecordDecl();
3956 if (RD->hasDefaultConstructor()) {
3957 TryValueInitialization(S, Entity, Kind, Sequence, InitList);
3962 // - Otherwise, if T is a specialization of std::initializer_list<E>,
3963 // an initializer_list object constructed [...]
3964 if (TryInitializerListConstruction(S, InitList, DestType, Sequence,
3965 TreatUnavailableAsInvalid))
3968 // - Otherwise, if T is a class type, constructors are considered.
3969 Expr *InitListAsExpr = InitList;
3970 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
3971 DestType, Sequence, /*InitListSyntax*/true);
3973 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType);
3977 if (S.getLangOpts().CPlusPlus && !DestType->isAggregateType() &&
3978 InitList->getNumInits() == 1) {
3979 Expr *E = InitList->getInit(0);
3981 // - Otherwise, if T is an enumeration with a fixed underlying type,
3982 // the initializer-list has a single element v, and the initialization
3983 // is direct-list-initialization, the object is initialized with the
3984 // value T(v); if a narrowing conversion is required to convert v to
3985 // the underlying type of T, the program is ill-formed.
3986 auto *ET = DestType->getAs<EnumType>();
3987 if (S.getLangOpts().CPlusPlus1z &&
3988 Kind.getKind() == InitializationKind::IK_DirectList &&
3989 ET && ET->getDecl()->isFixed() &&
3990 !S.Context.hasSameUnqualifiedType(E->getType(), DestType) &&
3991 (E->getType()->isIntegralOrEnumerationType() ||
3992 E->getType()->isFloatingType())) {
3993 // There are two ways that T(v) can work when T is an enumeration type.
3994 // If there is either an implicit conversion sequence from v to T or
3995 // a conversion function that can convert from v to T, then we use that.
3996 // Otherwise, if v is of integral, enumeration, or floating-point type,
3997 // it is converted to the enumeration type via its underlying type.
3998 // There is no overlap possible between these two cases (except when the
3999 // source value is already of the destination type), and the first
4000 // case is handled by the general case for single-element lists below.
4001 ImplicitConversionSequence ICS;
4003 ICS.Standard.setAsIdentityConversion();
4005 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
4006 // If E is of a floating-point type, then the conversion is ill-formed
4007 // due to narrowing, but go through the motions in order to produce the
4008 // right diagnostic.
4009 ICS.Standard.Second = E->getType()->isFloatingType()
4010 ? ICK_Floating_Integral
4011 : ICK_Integral_Conversion;
4012 ICS.Standard.setFromType(E->getType());
4013 ICS.Standard.setToType(0, E->getType());
4014 ICS.Standard.setToType(1, DestType);
4015 ICS.Standard.setToType(2, DestType);
4016 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2),
4017 /*TopLevelOfInitList*/true);
4018 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4022 // - Otherwise, if the initializer list has a single element of type E
4023 // [...references are handled above...], the object or reference is
4024 // initialized from that element (by copy-initialization for
4025 // copy-list-initialization, or by direct-initialization for
4026 // direct-list-initialization); if a narrowing conversion is required
4027 // to convert the element to T, the program is ill-formed.
4029 // Per core-24034, this is direct-initialization if we were performing
4030 // direct-list-initialization and copy-initialization otherwise.
4031 // We can't use InitListChecker for this, because it always performs
4032 // copy-initialization. This only matters if we might use an 'explicit'
4033 // conversion operator, so we only need to handle the cases where the source
4034 // is of record type.
4035 if (InitList->getInit(0)->getType()->isRecordType()) {
4036 InitializationKind SubKind =
4037 Kind.getKind() == InitializationKind::IK_DirectList
4038 ? InitializationKind::CreateDirect(Kind.getLocation(),
4039 InitList->getLBraceLoc(),
4040 InitList->getRBraceLoc())
4042 Expr *SubInit[1] = { InitList->getInit(0) };
4043 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
4044 /*TopLevelOfInitList*/true,
4045 TreatUnavailableAsInvalid);
4047 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4052 InitListChecker CheckInitList(S, Entity, InitList,
4053 DestType, /*VerifyOnly=*/true, TreatUnavailableAsInvalid);
4054 if (CheckInitList.HadError()) {
4055 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed);
4059 // Add the list initialization step with the built init list.
4060 Sequence.AddListInitializationStep(DestType);
4063 /// \brief Try a reference initialization that involves calling a conversion
4065 static OverloadingResult TryRefInitWithConversionFunction(
4066 Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
4067 Expr *Initializer, bool AllowRValues, bool IsLValueRef,
4068 InitializationSequence &Sequence) {
4069 QualType DestType = Entity.getType();
4070 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
4071 QualType T1 = cv1T1.getUnqualifiedType();
4072 QualType cv2T2 = Initializer->getType();
4073 QualType T2 = cv2T2.getUnqualifiedType();
4076 bool ObjCConversion;
4077 bool ObjCLifetimeConversion;
4078 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(),
4079 T1, T2, DerivedToBase,
4081 ObjCLifetimeConversion) &&
4082 "Must have incompatible references when binding via conversion");
4083 (void)DerivedToBase;
4084 (void)ObjCConversion;
4085 (void)ObjCLifetimeConversion;
4087 // Build the candidate set directly in the initialization sequence
4088 // structure, so that it will persist if we fail.
4089 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4090 CandidateSet.clear();
4092 // Determine whether we are allowed to call explicit constructors or
4093 // explicit conversion operators.
4094 bool AllowExplicit = Kind.AllowExplicit();
4095 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctionsInRefBinding();
4097 const RecordType *T1RecordType = nullptr;
4098 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) &&
4099 S.isCompleteType(Kind.getLocation(), T1)) {
4100 // The type we're converting to is a class type. Enumerate its constructors
4101 // to see if there is a suitable conversion.
4102 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl());
4104 for (NamedDecl *D : S.LookupConstructors(T1RecordDecl)) {
4105 auto Info = getConstructorInfo(D);
4106 if (!Info.Constructor)
4109 if (!Info.Constructor->isInvalidDecl() &&
4110 Info.Constructor->isConvertingConstructor(AllowExplicit)) {
4111 if (Info.ConstructorTmpl)
4112 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
4113 /*ExplicitArgs*/ nullptr,
4114 Initializer, CandidateSet,
4115 /*SuppressUserConversions=*/true);
4117 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
4118 Initializer, CandidateSet,
4119 /*SuppressUserConversions=*/true);
4123 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl())
4124 return OR_No_Viable_Function;
4126 const RecordType *T2RecordType = nullptr;
4127 if ((T2RecordType = T2->getAs<RecordType>()) &&
4128 S.isCompleteType(Kind.getLocation(), T2)) {
4129 // The type we're converting from is a class type, enumerate its conversion
4131 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
4133 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
4134 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4136 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4137 if (isa<UsingShadowDecl>(D))
4138 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4140 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4141 CXXConversionDecl *Conv;
4143 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4145 Conv = cast<CXXConversionDecl>(D);
4147 // If the conversion function doesn't return a reference type,
4148 // it can't be considered for this conversion unless we're allowed to
4149 // consider rvalues.
4150 // FIXME: Do we need to make sure that we only consider conversion
4151 // candidates with reference-compatible results? That might be needed to
4153 if ((AllowExplicitConvs || !Conv->isExplicit()) &&
4154 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){
4156 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(),
4157 ActingDC, Initializer,
4158 DestType, CandidateSet,
4159 /*AllowObjCConversionOnExplicit=*/
4162 S.AddConversionCandidate(Conv, I.getPair(), ActingDC,
4163 Initializer, DestType, CandidateSet,
4164 /*AllowObjCConversionOnExplicit=*/false);
4168 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl())
4169 return OR_No_Viable_Function;
4171 SourceLocation DeclLoc = Initializer->getLocStart();
4173 // Perform overload resolution. If it fails, return the failed result.
4174 OverloadCandidateSet::iterator Best;
4175 if (OverloadingResult Result
4176 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true))
4179 FunctionDecl *Function = Best->Function;
4180 // This is the overload that will be used for this initialization step if we
4181 // use this initialization. Mark it as referenced.
4182 Function->setReferenced();
4184 // Compute the returned type and value kind of the conversion.
4186 if (isa<CXXConversionDecl>(Function))
4187 cv3T3 = Function->getReturnType();
4191 ExprValueKind VK = VK_RValue;
4192 if (cv3T3->isLValueReferenceType())
4194 else if (const auto *RRef = cv3T3->getAs<RValueReferenceType>())
4195 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue;
4196 cv3T3 = cv3T3.getNonLValueExprType(S.Context);
4198 // Add the user-defined conversion step.
4199 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4200 Sequence.AddUserConversionStep(Function, Best->FoundDecl, cv3T3,
4201 HadMultipleCandidates);
4203 // Determine whether we'll need to perform derived-to-base adjustments or
4204 // other conversions.
4205 bool NewDerivedToBase = false;
4206 bool NewObjCConversion = false;
4207 bool NewObjCLifetimeConversion = false;
4208 Sema::ReferenceCompareResult NewRefRelationship
4209 = S.CompareReferenceRelationship(DeclLoc, T1, cv3T3,
4210 NewDerivedToBase, NewObjCConversion,
4211 NewObjCLifetimeConversion);
4213 // Add the final conversion sequence, if necessary.
4214 if (NewRefRelationship == Sema::Ref_Incompatible) {
4215 assert(!isa<CXXConstructorDecl>(Function) &&
4216 "should not have conversion after constructor");
4218 ImplicitConversionSequence ICS;
4220 ICS.Standard = Best->FinalConversion;
4221 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2));
4223 // Every implicit conversion results in a prvalue, except for a glvalue
4224 // derived-to-base conversion, which we handle below.
4225 cv3T3 = ICS.Standard.getToType(2);
4229 // If the converted initializer is a prvalue, its type T4 is adjusted to
4230 // type "cv1 T4" and the temporary materialization conversion is applied.
4232 // We adjust the cv-qualifications to match the reference regardless of
4233 // whether we have a prvalue so that the AST records the change. In this
4234 // case, T4 is "cv3 T3".
4235 QualType cv1T4 = S.Context.getQualifiedType(cv3T3, cv1T1.getQualifiers());
4236 if (cv1T4.getQualifiers() != cv3T3.getQualifiers())
4237 Sequence.AddQualificationConversionStep(cv1T4, VK);
4238 Sequence.AddReferenceBindingStep(cv1T4, VK == VK_RValue);
4239 VK = IsLValueRef ? VK_LValue : VK_XValue;
4241 if (NewDerivedToBase)
4242 Sequence.AddDerivedToBaseCastStep(cv1T1, VK);
4243 else if (NewObjCConversion)
4244 Sequence.AddObjCObjectConversionStep(cv1T1);
4249 static void CheckCXX98CompatAccessibleCopy(Sema &S,
4250 const InitializedEntity &Entity,
4253 /// \brief Attempt reference initialization (C++0x [dcl.init.ref])
4254 static void TryReferenceInitialization(Sema &S,
4255 const InitializedEntity &Entity,
4256 const InitializationKind &Kind,
4258 InitializationSequence &Sequence) {
4259 QualType DestType = Entity.getType();
4260 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
4262 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
4263 QualType cv2T2 = Initializer->getType();
4265 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
4267 // If the initializer is the address of an overloaded function, try
4268 // to resolve the overloaded function. If all goes well, T2 is the
4269 // type of the resulting function.
4270 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
4274 // Delegate everything else to a subfunction.
4275 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
4276 T1Quals, cv2T2, T2, T2Quals, Sequence);
4279 /// Determine whether an expression is a non-referenceable glvalue (one to
4280 /// which a reference can never bind). Attemting to bind a reference to
4281 /// such a glvalue will always create a temporary.
4282 static bool isNonReferenceableGLValue(Expr *E) {
4283 return E->refersToBitField() || E->refersToVectorElement();
4286 /// \brief Reference initialization without resolving overloaded functions.
4287 static void TryReferenceInitializationCore(Sema &S,
4288 const InitializedEntity &Entity,
4289 const InitializationKind &Kind,
4291 QualType cv1T1, QualType T1,
4293 QualType cv2T2, QualType T2,
4295 InitializationSequence &Sequence) {
4296 QualType DestType = Entity.getType();
4297 SourceLocation DeclLoc = Initializer->getLocStart();
4298 // Compute some basic properties of the types and the initializer.
4299 bool isLValueRef = DestType->isLValueReferenceType();
4300 bool isRValueRef = !isLValueRef;
4301 bool DerivedToBase = false;
4302 bool ObjCConversion = false;
4303 bool ObjCLifetimeConversion = false;
4304 Expr::Classification InitCategory = Initializer->Classify(S.Context);
4305 Sema::ReferenceCompareResult RefRelationship
4306 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase,
4307 ObjCConversion, ObjCLifetimeConversion);
4309 // C++0x [dcl.init.ref]p5:
4310 // A reference to type "cv1 T1" is initialized by an expression of type
4311 // "cv2 T2" as follows:
4313 // - If the reference is an lvalue reference and the initializer
4315 // Note the analogous bullet points for rvalue refs to functions. Because
4316 // there are no function rvalues in C++, rvalue refs to functions are treated
4317 // like lvalue refs.
4318 OverloadingResult ConvOvlResult = OR_Success;
4319 bool T1Function = T1->isFunctionType();
4320 if (isLValueRef || T1Function) {
4321 if (InitCategory.isLValue() && !isNonReferenceableGLValue(Initializer) &&
4322 (RefRelationship == Sema::Ref_Compatible ||
4323 (Kind.isCStyleOrFunctionalCast() &&
4324 RefRelationship == Sema::Ref_Related))) {
4325 // - is an lvalue (but is not a bit-field), and "cv1 T1" is
4326 // reference-compatible with "cv2 T2," or
4327 if (T1Quals != T2Quals)
4328 // Convert to cv1 T2. This should only add qualifiers unless this is a
4329 // c-style cast. The removal of qualifiers in that case notionally
4330 // happens after the reference binding, but that doesn't matter.
4331 Sequence.AddQualificationConversionStep(
4332 S.Context.getQualifiedType(T2, T1Quals),
4333 Initializer->getValueKind());
4335 Sequence.AddDerivedToBaseCastStep(cv1T1, VK_LValue);
4336 else if (ObjCConversion)
4337 Sequence.AddObjCObjectConversionStep(cv1T1);
4339 // We only create a temporary here when binding a reference to a
4340 // bit-field or vector element. Those cases are't supposed to be
4341 // handled by this bullet, but the outcome is the same either way.
4342 Sequence.AddReferenceBindingStep(cv1T1, false);
4346 // - has a class type (i.e., T2 is a class type), where T1 is not
4347 // reference-related to T2, and can be implicitly converted to an
4348 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible
4349 // with "cv3 T3" (this conversion is selected by enumerating the
4350 // applicable conversion functions (13.3.1.6) and choosing the best
4351 // one through overload resolution (13.3)),
4352 // If we have an rvalue ref to function type here, the rhs must be
4353 // an rvalue. DR1287 removed the "implicitly" here.
4354 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() &&
4355 (isLValueRef || InitCategory.isRValue())) {
4356 ConvOvlResult = TryRefInitWithConversionFunction(
4357 S, Entity, Kind, Initializer, /*AllowRValues*/ isRValueRef,
4358 /*IsLValueRef*/ isLValueRef, Sequence);
4359 if (ConvOvlResult == OR_Success)
4361 if (ConvOvlResult != OR_No_Viable_Function)
4362 Sequence.SetOverloadFailure(
4363 InitializationSequence::FK_ReferenceInitOverloadFailed,
4368 // - Otherwise, the reference shall be an lvalue reference to a
4369 // non-volatile const type (i.e., cv1 shall be const), or the reference
4370 // shall be an rvalue reference.
4371 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile())) {
4372 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4373 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4374 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4375 Sequence.SetOverloadFailure(
4376 InitializationSequence::FK_ReferenceInitOverloadFailed,
4378 else if (!InitCategory.isLValue())
4380 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
4382 InitializationSequence::FailureKind FK;
4383 switch (RefRelationship) {
4384 case Sema::Ref_Compatible:
4385 if (Initializer->refersToBitField())
4386 FK = InitializationSequence::
4387 FK_NonConstLValueReferenceBindingToBitfield;
4388 else if (Initializer->refersToVectorElement())
4389 FK = InitializationSequence::
4390 FK_NonConstLValueReferenceBindingToVectorElement;
4392 llvm_unreachable("unexpected kind of compatible initializer");
4394 case Sema::Ref_Related:
4395 FK = InitializationSequence::FK_ReferenceInitDropsQualifiers;
4397 case Sema::Ref_Incompatible:
4398 FK = InitializationSequence::
4399 FK_NonConstLValueReferenceBindingToUnrelated;
4402 Sequence.SetFailed(FK);
4407 // - If the initializer expression
4409 // [<=14] xvalue (but not a bit-field), class prvalue, array prvalue, or
4410 // [1z] rvalue (but not a bit-field) or
4411 // function lvalue and "cv1 T1" is reference-compatible with "cv2 T2"
4413 // Note: functions are handled above and below rather than here...
4415 (RefRelationship == Sema::Ref_Compatible ||
4416 (Kind.isCStyleOrFunctionalCast() &&
4417 RefRelationship == Sema::Ref_Related)) &&
4418 ((InitCategory.isXValue() && !isNonReferenceableGLValue(Initializer)) ||
4419 (InitCategory.isPRValue() &&
4420 (S.getLangOpts().CPlusPlus1z || T2->isRecordType() ||
4421 T2->isArrayType())))) {
4422 ExprValueKind ValueKind = InitCategory.isXValue() ? VK_XValue : VK_RValue;
4423 if (InitCategory.isPRValue() && T2->isRecordType()) {
4424 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the
4425 // compiler the freedom to perform a copy here or bind to the
4426 // object, while C++0x requires that we bind directly to the
4427 // object. Hence, we always bind to the object without making an
4428 // extra copy. However, in C++03 requires that we check for the
4429 // presence of a suitable copy constructor:
4431 // The constructor that would be used to make the copy shall
4432 // be callable whether or not the copy is actually done.
4433 if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt)
4434 Sequence.AddExtraneousCopyToTemporary(cv2T2);
4435 else if (S.getLangOpts().CPlusPlus11)
4436 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer);
4439 // C++1z [dcl.init.ref]/5.2.1.2:
4440 // If the converted initializer is a prvalue, its type T4 is adjusted
4441 // to type "cv1 T4" and the temporary materialization conversion is
4443 QualType cv1T4 = S.Context.getQualifiedType(cv2T2, T1Quals);
4444 if (T1Quals != T2Quals)
4445 Sequence.AddQualificationConversionStep(cv1T4, ValueKind);
4446 Sequence.AddReferenceBindingStep(cv1T4, ValueKind == VK_RValue);
4447 ValueKind = isLValueRef ? VK_LValue : VK_XValue;
4449 // In any case, the reference is bound to the resulting glvalue (or to
4450 // an appropriate base class subobject).
4452 Sequence.AddDerivedToBaseCastStep(cv1T1, ValueKind);
4453 else if (ObjCConversion)
4454 Sequence.AddObjCObjectConversionStep(cv1T1);
4458 // - has a class type (i.e., T2 is a class type), where T1 is not
4459 // reference-related to T2, and can be implicitly converted to an
4460 // xvalue, class prvalue, or function lvalue of type "cv3 T3",
4461 // where "cv1 T1" is reference-compatible with "cv3 T3",
4463 // DR1287 removes the "implicitly" here.
4464 if (T2->isRecordType()) {
4465 if (RefRelationship == Sema::Ref_Incompatible) {
4466 ConvOvlResult = TryRefInitWithConversionFunction(
4467 S, Entity, Kind, Initializer, /*AllowRValues*/ true,
4468 /*IsLValueRef*/ isLValueRef, Sequence);
4470 Sequence.SetOverloadFailure(
4471 InitializationSequence::FK_ReferenceInitOverloadFailed,
4477 if (RefRelationship == Sema::Ref_Compatible &&
4478 isRValueRef && InitCategory.isLValue()) {
4480 InitializationSequence::FK_RValueReferenceBindingToLValue);
4484 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
4488 // - Otherwise, a temporary of type "cv1 T1" is created and initialized
4489 // from the initializer expression using the rules for a non-reference
4490 // copy-initialization (8.5). The reference is then bound to the
4493 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
4495 // FIXME: Why do we use an implicit conversion here rather than trying
4496 // copy-initialization?
4497 ImplicitConversionSequence ICS
4498 = S.TryImplicitConversion(Initializer, TempEntity.getType(),
4499 /*SuppressUserConversions=*/false,
4500 /*AllowExplicit=*/false,
4501 /*FIXME:InOverloadResolution=*/false,
4502 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
4503 /*AllowObjCWritebackConversion=*/false);
4506 // FIXME: Use the conversion function set stored in ICS to turn
4507 // this into an overloading ambiguity diagnostic. However, we need
4508 // to keep that set as an OverloadCandidateSet rather than as some
4509 // other kind of set.
4510 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4511 Sequence.SetOverloadFailure(
4512 InitializationSequence::FK_ReferenceInitOverloadFailed,
4514 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4515 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4517 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed);
4520 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType());
4523 // [...] If T1 is reference-related to T2, cv1 must be the
4524 // same cv-qualification as, or greater cv-qualification
4525 // than, cv2; otherwise, the program is ill-formed.
4526 unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
4527 unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
4528 if (RefRelationship == Sema::Ref_Related &&
4529 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) {
4530 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
4534 // [...] If T1 is reference-related to T2 and the reference is an rvalue
4535 // reference, the initializer expression shall not be an lvalue.
4536 if (RefRelationship >= Sema::Ref_Related && !isLValueRef &&
4537 InitCategory.isLValue()) {
4539 InitializationSequence::FK_RValueReferenceBindingToLValue);
4543 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
4546 /// \brief Attempt character array initialization from a string literal
4547 /// (C++ [dcl.init.string], C99 6.7.8).
4548 static void TryStringLiteralInitialization(Sema &S,
4549 const InitializedEntity &Entity,
4550 const InitializationKind &Kind,
4552 InitializationSequence &Sequence) {
4553 Sequence.AddStringInitStep(Entity.getType());
4556 /// \brief Attempt value initialization (C++ [dcl.init]p7).
4557 static void TryValueInitialization(Sema &S,
4558 const InitializedEntity &Entity,
4559 const InitializationKind &Kind,
4560 InitializationSequence &Sequence,
4561 InitListExpr *InitList) {
4562 assert((!InitList || InitList->getNumInits() == 0) &&
4563 "Shouldn't use value-init for non-empty init lists");
4565 // C++98 [dcl.init]p5, C++11 [dcl.init]p7:
4567 // To value-initialize an object of type T means:
4568 QualType T = Entity.getType();
4570 // -- if T is an array type, then each element is value-initialized;
4571 T = S.Context.getBaseElementType(T);
4573 if (const RecordType *RT = T->getAs<RecordType>()) {
4574 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
4575 bool NeedZeroInitialization = true;
4577 // -- if T is a class type (clause 9) with a user-declared constructor
4578 // (12.1), then the default constructor for T is called (and the
4579 // initialization is ill-formed if T has no accessible default
4582 // -- if T is a class type (clause 9) with either no default constructor
4583 // (12.1 [class.ctor]) or a default constructor that is user-provided
4584 // or deleted, then the object is default-initialized;
4586 // Note that the C++11 rule is the same as the C++98 rule if there are no
4587 // defaulted or deleted constructors, so we just use it unconditionally.
4588 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl);
4589 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted())
4590 NeedZeroInitialization = false;
4592 // -- if T is a (possibly cv-qualified) non-union class type without a
4593 // user-provided or deleted default constructor, then the object is
4594 // zero-initialized and, if T has a non-trivial default constructor,
4595 // default-initialized;
4596 // The 'non-union' here was removed by DR1502. The 'non-trivial default
4597 // constructor' part was removed by DR1507.
4598 if (NeedZeroInitialization)
4599 Sequence.AddZeroInitializationStep(Entity.getType());
4602 // -- if T is a non-union class type without a user-declared constructor,
4603 // then every non-static data member and base class component of T is
4604 // value-initialized;
4605 // [...] A program that calls for [...] value-initialization of an
4606 // entity of reference type is ill-formed.
4608 // C++11 doesn't need this handling, because value-initialization does not
4609 // occur recursively there, and the implicit default constructor is
4610 // defined as deleted in the problematic cases.
4611 if (!S.getLangOpts().CPlusPlus11 &&
4612 ClassDecl->hasUninitializedReferenceMember()) {
4613 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference);
4617 // If this is list-value-initialization, pass the empty init list on when
4618 // building the constructor call. This affects the semantics of a few
4619 // things (such as whether an explicit default constructor can be called).
4620 Expr *InitListAsExpr = InitList;
4621 MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0);
4622 bool InitListSyntax = InitList;
4624 // FIXME: Instead of creating a CXXConstructExpr of array type here,
4625 // wrap a class-typed CXXConstructExpr in an ArrayInitLoopExpr.
4626 return TryConstructorInitialization(
4627 S, Entity, Kind, Args, T, Entity.getType(), Sequence, InitListSyntax);
4631 Sequence.AddZeroInitializationStep(Entity.getType());
4634 /// \brief Attempt default initialization (C++ [dcl.init]p6).
4635 static void TryDefaultInitialization(Sema &S,
4636 const InitializedEntity &Entity,
4637 const InitializationKind &Kind,
4638 InitializationSequence &Sequence) {
4639 assert(Kind.getKind() == InitializationKind::IK_Default);
4641 // C++ [dcl.init]p6:
4642 // To default-initialize an object of type T means:
4643 // - if T is an array type, each element is default-initialized;
4644 QualType DestType = S.Context.getBaseElementType(Entity.getType());
4646 // - if T is a (possibly cv-qualified) class type (Clause 9), the default
4647 // constructor for T is called (and the initialization is ill-formed if
4648 // T has no accessible default constructor);
4649 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) {
4650 TryConstructorInitialization(S, Entity, Kind, None, DestType,
4651 Entity.getType(), Sequence);
4655 // - otherwise, no initialization is performed.
4657 // If a program calls for the default initialization of an object of
4658 // a const-qualified type T, T shall be a class type with a user-provided
4659 // default constructor.
4660 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) {
4661 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
4662 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
4666 // If the destination type has a lifetime property, zero-initialize it.
4667 if (DestType.getQualifiers().hasObjCLifetime()) {
4668 Sequence.AddZeroInitializationStep(Entity.getType());
4673 /// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]),
4674 /// which enumerates all conversion functions and performs overload resolution
4675 /// to select the best.
4676 static void TryUserDefinedConversion(Sema &S,
4678 const InitializationKind &Kind,
4680 InitializationSequence &Sequence,
4681 bool TopLevelOfInitList) {
4682 assert(!DestType->isReferenceType() && "References are handled elsewhere");
4683 QualType SourceType = Initializer->getType();
4684 assert((DestType->isRecordType() || SourceType->isRecordType()) &&
4685 "Must have a class type to perform a user-defined conversion");
4687 // Build the candidate set directly in the initialization sequence
4688 // structure, so that it will persist if we fail.
4689 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4690 CandidateSet.clear();
4692 // Determine whether we are allowed to call explicit constructors or
4693 // explicit conversion operators.
4694 bool AllowExplicit = Kind.AllowExplicit();
4696 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) {
4697 // The type we're converting to is a class type. Enumerate its constructors
4698 // to see if there is a suitable conversion.
4699 CXXRecordDecl *DestRecordDecl
4700 = cast<CXXRecordDecl>(DestRecordType->getDecl());
4702 // Try to complete the type we're converting to.
4703 if (S.isCompleteType(Kind.getLocation(), DestType)) {
4704 for (NamedDecl *D : S.LookupConstructors(DestRecordDecl)) {
4705 auto Info = getConstructorInfo(D);
4706 if (!Info.Constructor)
4709 if (!Info.Constructor->isInvalidDecl() &&
4710 Info.Constructor->isConvertingConstructor(AllowExplicit)) {
4711 if (Info.ConstructorTmpl)
4712 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
4713 /*ExplicitArgs*/ nullptr,
4714 Initializer, CandidateSet,
4715 /*SuppressUserConversions=*/true);
4717 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
4718 Initializer, CandidateSet,
4719 /*SuppressUserConversions=*/true);
4725 SourceLocation DeclLoc = Initializer->getLocStart();
4727 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) {
4728 // The type we're converting from is a class type, enumerate its conversion
4731 // We can only enumerate the conversion functions for a complete type; if
4732 // the type isn't complete, simply skip this step.
4733 if (S.isCompleteType(DeclLoc, SourceType)) {
4734 CXXRecordDecl *SourceRecordDecl
4735 = cast<CXXRecordDecl>(SourceRecordType->getDecl());
4737 const auto &Conversions =
4738 SourceRecordDecl->getVisibleConversionFunctions();
4739 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4741 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4742 if (isa<UsingShadowDecl>(D))
4743 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4745 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4746 CXXConversionDecl *Conv;
4748 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4750 Conv = cast<CXXConversionDecl>(D);
4752 if (AllowExplicit || !Conv->isExplicit()) {
4754 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(),
4755 ActingDC, Initializer, DestType,
4756 CandidateSet, AllowExplicit);
4758 S.AddConversionCandidate(Conv, I.getPair(), ActingDC,
4759 Initializer, DestType, CandidateSet,
4766 // Perform overload resolution. If it fails, return the failed result.
4767 OverloadCandidateSet::iterator Best;
4768 if (OverloadingResult Result
4769 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) {
4770 Sequence.SetOverloadFailure(
4771 InitializationSequence::FK_UserConversionOverloadFailed,
4776 FunctionDecl *Function = Best->Function;
4777 Function->setReferenced();
4778 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4780 if (isa<CXXConstructorDecl>(Function)) {
4781 // Add the user-defined conversion step. Any cv-qualification conversion is
4782 // subsumed by the initialization. Per DR5, the created temporary is of the
4783 // cv-unqualified type of the destination.
4784 Sequence.AddUserConversionStep(Function, Best->FoundDecl,
4785 DestType.getUnqualifiedType(),
4786 HadMultipleCandidates);
4788 // C++14 and before:
4789 // - if the function is a constructor, the call initializes a temporary
4790 // of the cv-unqualified version of the destination type. The [...]
4791 // temporary [...] is then used to direct-initialize, according to the
4792 // rules above, the object that is the destination of the
4793 // copy-initialization.
4794 // Note that this just performs a simple object copy from the temporary.
4797 // - if the function is a constructor, the call is a prvalue of the
4798 // cv-unqualified version of the destination type whose return object
4799 // is initialized by the constructor. The call is used to
4800 // direct-initialize, according to the rules above, the object that
4801 // is the destination of the copy-initialization.
4802 // Therefore we need to do nothing further.
4804 // FIXME: Mark this copy as extraneous.
4805 if (!S.getLangOpts().CPlusPlus1z)
4806 Sequence.AddFinalCopy(DestType);
4807 else if (DestType.hasQualifiers())
4808 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
4812 // Add the user-defined conversion step that calls the conversion function.
4813 QualType ConvType = Function->getCallResultType();
4814 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType,
4815 HadMultipleCandidates);
4817 if (ConvType->getAs<RecordType>()) {
4818 // The call is used to direct-initialize [...] the object that is the
4819 // destination of the copy-initialization.
4821 // In C++1z, this does not call a constructor if we enter /17.6.1:
4822 // - If the initializer expression is a prvalue and the cv-unqualified
4823 // version of the source type is the same as the class of the
4824 // destination [... do not make an extra copy]
4826 // FIXME: Mark this copy as extraneous.
4827 if (!S.getLangOpts().CPlusPlus1z ||
4828 Function->getReturnType()->isReferenceType() ||
4829 !S.Context.hasSameUnqualifiedType(ConvType, DestType))
4830 Sequence.AddFinalCopy(DestType);
4831 else if (!S.Context.hasSameType(ConvType, DestType))
4832 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
4836 // If the conversion following the call to the conversion function
4837 // is interesting, add it as a separate step.
4838 if (Best->FinalConversion.First || Best->FinalConversion.Second ||
4839 Best->FinalConversion.Third) {
4840 ImplicitConversionSequence ICS;
4842 ICS.Standard = Best->FinalConversion;
4843 Sequence.AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
4847 /// An egregious hack for compatibility with libstdc++-4.2: in <tr1/hashtable>,
4848 /// a function with a pointer return type contains a 'return false;' statement.
4849 /// In C++11, 'false' is not a null pointer, so this breaks the build of any
4850 /// code using that header.
4852 /// Work around this by treating 'return false;' as zero-initializing the result
4853 /// if it's used in a pointer-returning function in a system header.
4854 static bool isLibstdcxxPointerReturnFalseHack(Sema &S,
4855 const InitializedEntity &Entity,
4857 return S.getLangOpts().CPlusPlus11 &&
4858 Entity.getKind() == InitializedEntity::EK_Result &&
4859 Entity.getType()->isPointerType() &&
4860 isa<CXXBoolLiteralExpr>(Init) &&
4861 !cast<CXXBoolLiteralExpr>(Init)->getValue() &&
4862 S.getSourceManager().isInSystemHeader(Init->getExprLoc());
4865 /// The non-zero enum values here are indexes into diagnostic alternatives.
4866 enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar };
4868 /// Determines whether this expression is an acceptable ICR source.
4869 static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e,
4870 bool isAddressOf, bool &isWeakAccess) {
4872 e = e->IgnoreParens();
4874 // Skip address-of nodes.
4875 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
4876 if (op->getOpcode() == UO_AddrOf)
4877 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true,
4880 // Skip certain casts.
4881 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) {
4882 switch (ce->getCastKind()) {
4885 case CK_LValueBitCast:
4887 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess);
4889 case CK_ArrayToPointerDecay:
4890 return IIK_nonscalar;
4892 case CK_NullToPointer:
4899 // If we have a declaration reference, it had better be a local variable.
4900 } else if (isa<DeclRefExpr>(e)) {
4901 // set isWeakAccess to true, to mean that there will be an implicit
4902 // load which requires a cleanup.
4903 if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
4904 isWeakAccess = true;
4906 if (!isAddressOf) return IIK_nonlocal;
4908 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl());
4909 if (!var) return IIK_nonlocal;
4911 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal);
4913 // If we have a conditional operator, check both sides.
4914 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) {
4915 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf,
4919 return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess);
4921 // These are never scalar.
4922 } else if (isa<ArraySubscriptExpr>(e)) {
4923 return IIK_nonscalar;
4925 // Otherwise, it needs to be a null pointer constant.
4927 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull)
4928 ? IIK_okay : IIK_nonlocal);
4931 return IIK_nonlocal;
4934 /// Check whether the given expression is a valid operand for an
4935 /// indirect copy/restore.
4936 static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) {
4937 assert(src->isRValue());
4938 bool isWeakAccess = false;
4939 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess);
4940 // If isWeakAccess to true, there will be an implicit
4941 // load which requires a cleanup.
4942 if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess)
4943 S.Cleanup.setExprNeedsCleanups(true);
4945 if (iik == IIK_okay) return;
4947 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback)
4948 << ((unsigned) iik - 1) // shift index into diagnostic explanations
4949 << src->getSourceRange();
4952 /// \brief Determine whether we have compatible array types for the
4953 /// purposes of GNU by-copy array initialization.
4954 static bool hasCompatibleArrayTypes(ASTContext &Context, const ArrayType *Dest,
4955 const ArrayType *Source) {
4956 // If the source and destination array types are equivalent, we're
4958 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0)))
4961 // Make sure that the element types are the same.
4962 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType()))
4965 // The only mismatch we allow is when the destination is an
4966 // incomplete array type and the source is a constant array type.
4967 return Source->isConstantArrayType() && Dest->isIncompleteArrayType();
4970 static bool tryObjCWritebackConversion(Sema &S,
4971 InitializationSequence &Sequence,
4972 const InitializedEntity &Entity,
4973 Expr *Initializer) {
4974 bool ArrayDecay = false;
4975 QualType ArgType = Initializer->getType();
4976 QualType ArgPointee;
4977 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) {
4979 ArgPointee = ArgArrayType->getElementType();
4980 ArgType = S.Context.getPointerType(ArgPointee);
4983 // Handle write-back conversion.
4984 QualType ConvertedArgType;
4985 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(),
4989 // We should copy unless we're passing to an argument explicitly
4991 bool ShouldCopy = true;
4992 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
4993 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
4995 // Do we need an lvalue conversion?
4996 if (ArrayDecay || Initializer->isGLValue()) {
4997 ImplicitConversionSequence ICS;
4999 ICS.Standard.setAsIdentityConversion();
5001 QualType ResultType;
5003 ICS.Standard.First = ICK_Array_To_Pointer;
5004 ResultType = S.Context.getPointerType(ArgPointee);
5006 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
5007 ResultType = Initializer->getType().getNonLValueExprType(S.Context);
5010 Sequence.AddConversionSequenceStep(ICS, ResultType);
5013 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy);
5017 static bool TryOCLSamplerInitialization(Sema &S,
5018 InitializationSequence &Sequence,
5020 Expr *Initializer) {
5021 if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() ||
5022 (!Initializer->isIntegerConstantExpr(S.Context) &&
5023 !Initializer->getType()->isSamplerT()))
5026 Sequence.AddOCLSamplerInitStep(DestType);
5031 // OpenCL 1.2 spec, s6.12.10
5033 // The event argument can also be used to associate the
5034 // async_work_group_copy with a previous async copy allowing
5035 // an event to be shared by multiple async copies; otherwise
5036 // event should be zero.
5038 static bool TryOCLZeroEventInitialization(Sema &S,
5039 InitializationSequence &Sequence,
5041 Expr *Initializer) {
5042 if (!S.getLangOpts().OpenCL || !DestType->isEventT() ||
5043 !Initializer->isIntegerConstantExpr(S.getASTContext()) ||
5044 (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0))
5047 Sequence.AddOCLZeroEventStep(DestType);
5051 static bool TryOCLZeroQueueInitialization(Sema &S,
5052 InitializationSequence &Sequence,
5054 Expr *Initializer) {
5055 if (!S.getLangOpts().OpenCL || S.getLangOpts().OpenCLVersion < 200 ||
5056 !DestType->isQueueT() ||
5057 !Initializer->isIntegerConstantExpr(S.getASTContext()) ||
5058 (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0))
5061 Sequence.AddOCLZeroQueueStep(DestType);
5065 InitializationSequence::InitializationSequence(Sema &S,
5066 const InitializedEntity &Entity,
5067 const InitializationKind &Kind,
5069 bool TopLevelOfInitList,
5070 bool TreatUnavailableAsInvalid)
5071 : FailedCandidateSet(Kind.getLocation(), OverloadCandidateSet::CSK_Normal) {
5072 InitializeFrom(S, Entity, Kind, Args, TopLevelOfInitList,
5073 TreatUnavailableAsInvalid);
5076 /// Tries to get a FunctionDecl out of `E`. If it succeeds and we can take the
5077 /// address of that function, this returns true. Otherwise, it returns false.
5078 static bool isExprAnUnaddressableFunction(Sema &S, const Expr *E) {
5079 auto *DRE = dyn_cast<DeclRefExpr>(E);
5080 if (!DRE || !isa<FunctionDecl>(DRE->getDecl()))
5083 return !S.checkAddressOfFunctionIsAvailable(
5084 cast<FunctionDecl>(DRE->getDecl()));
5087 /// Determine whether we can perform an elementwise array copy for this kind
5089 static bool canPerformArrayCopy(const InitializedEntity &Entity) {
5090 switch (Entity.getKind()) {
5091 case InitializedEntity::EK_LambdaCapture:
5092 // C++ [expr.prim.lambda]p24:
5093 // For array members, the array elements are direct-initialized in
5094 // increasing subscript order.
5097 case InitializedEntity::EK_Variable:
5098 // C++ [dcl.decomp]p1:
5099 // [...] each element is copy-initialized or direct-initialized from the
5100 // corresponding element of the assignment-expression [...]
5101 return isa<DecompositionDecl>(Entity.getDecl());
5103 case InitializedEntity::EK_Member:
5104 // C++ [class.copy.ctor]p14:
5105 // - if the member is an array, each element is direct-initialized with
5106 // the corresponding subobject of x
5107 return Entity.isImplicitMemberInitializer();
5109 case InitializedEntity::EK_ArrayElement:
5110 // All the above cases are intended to apply recursively, even though none
5111 // of them actually say that.
5112 if (auto *E = Entity.getParent())
5113 return canPerformArrayCopy(*E);
5123 void InitializationSequence::InitializeFrom(Sema &S,
5124 const InitializedEntity &Entity,
5125 const InitializationKind &Kind,
5127 bool TopLevelOfInitList,
5128 bool TreatUnavailableAsInvalid) {
5129 ASTContext &Context = S.Context;
5131 // Eliminate non-overload placeholder types in the arguments. We
5132 // need to do this before checking whether types are dependent
5133 // because lowering a pseudo-object expression might well give us
5134 // something of dependent type.
5135 for (unsigned I = 0, E = Args.size(); I != E; ++I)
5136 if (Args[I]->getType()->isNonOverloadPlaceholderType()) {
5137 // FIXME: should we be doing this here?
5138 ExprResult result = S.CheckPlaceholderExpr(Args[I]);
5139 if (result.isInvalid()) {
5140 SetFailed(FK_PlaceholderType);
5143 Args[I] = result.get();
5146 // C++0x [dcl.init]p16:
5147 // The semantics of initializers are as follows. The destination type is
5148 // the type of the object or reference being initialized and the source
5149 // type is the type of the initializer expression. The source type is not
5150 // defined when the initializer is a braced-init-list or when it is a
5151 // parenthesized list of expressions.
5152 QualType DestType = Entity.getType();
5154 if (DestType->isDependentType() ||
5155 Expr::hasAnyTypeDependentArguments(Args)) {
5156 SequenceKind = DependentSequence;
5160 // Almost everything is a normal sequence.
5161 setSequenceKind(NormalSequence);
5163 QualType SourceType;
5164 Expr *Initializer = nullptr;
5165 if (Args.size() == 1) {
5166 Initializer = Args[0];
5167 if (S.getLangOpts().ObjC1) {
5168 if (S.CheckObjCBridgeRelatedConversions(Initializer->getLocStart(),
5169 DestType, Initializer->getType(),
5171 S.ConversionToObjCStringLiteralCheck(DestType, Initializer))
5172 Args[0] = Initializer;
5174 if (!isa<InitListExpr>(Initializer))
5175 SourceType = Initializer->getType();
5178 // - If the initializer is a (non-parenthesized) braced-init-list, the
5179 // object is list-initialized (8.5.4).
5180 if (Kind.getKind() != InitializationKind::IK_Direct) {
5181 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) {
5182 TryListInitialization(S, Entity, Kind, InitList, *this,
5183 TreatUnavailableAsInvalid);
5188 // - If the destination type is a reference type, see 8.5.3.
5189 if (DestType->isReferenceType()) {
5190 // C++0x [dcl.init.ref]p1:
5191 // A variable declared to be a T& or T&&, that is, "reference to type T"
5192 // (8.3.2), shall be initialized by an object, or function, of type T or
5193 // by an object that can be converted into a T.
5194 // (Therefore, multiple arguments are not permitted.)
5195 if (Args.size() != 1)
5196 SetFailed(FK_TooManyInitsForReference);
5197 // C++17 [dcl.init.ref]p5:
5198 // A reference [...] is initialized by an expression [...] as follows:
5199 // If the initializer is not an expression, presumably we should reject,
5200 // but the standard fails to actually say so.
5201 else if (isa<InitListExpr>(Args[0]))
5202 SetFailed(FK_ParenthesizedListInitForReference);
5204 TryReferenceInitialization(S, Entity, Kind, Args[0], *this);
5208 // - If the initializer is (), the object is value-initialized.
5209 if (Kind.getKind() == InitializationKind::IK_Value ||
5210 (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) {
5211 TryValueInitialization(S, Entity, Kind, *this);
5215 // Handle default initialization.
5216 if (Kind.getKind() == InitializationKind::IK_Default) {
5217 TryDefaultInitialization(S, Entity, Kind, *this);
5221 // - If the destination type is an array of characters, an array of
5222 // char16_t, an array of char32_t, or an array of wchar_t, and the
5223 // initializer is a string literal, see 8.5.2.
5224 // - Otherwise, if the destination type is an array, the program is
5226 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) {
5227 if (Initializer && isa<VariableArrayType>(DestAT)) {
5228 SetFailed(FK_VariableLengthArrayHasInitializer);
5233 switch (IsStringInit(Initializer, DestAT, Context)) {
5235 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this);
5237 case SIF_NarrowStringIntoWideChar:
5238 SetFailed(FK_NarrowStringIntoWideCharArray);
5240 case SIF_WideStringIntoChar:
5241 SetFailed(FK_WideStringIntoCharArray);
5243 case SIF_IncompatWideStringIntoWideChar:
5244 SetFailed(FK_IncompatWideStringIntoWideChar);
5251 // Some kinds of initialization permit an array to be initialized from
5252 // another array of the same type, and perform elementwise initialization.
5253 if (Initializer && isa<ConstantArrayType>(DestAT) &&
5254 S.Context.hasSameUnqualifiedType(Initializer->getType(),
5255 Entity.getType()) &&
5256 canPerformArrayCopy(Entity)) {
5257 // If source is a prvalue, use it directly.
5258 if (Initializer->getValueKind() == VK_RValue) {
5259 AddArrayInitStep(DestType, /*IsGNUExtension*/false);
5263 // Emit element-at-a-time copy loop.
5264 InitializedEntity Element =
5265 InitializedEntity::InitializeElement(S.Context, 0, Entity);
5267 Context.getAsArrayType(Initializer->getType())->getElementType();
5268 OpaqueValueExpr OVE(Initializer->getExprLoc(), InitEltT,
5269 Initializer->getValueKind(),
5270 Initializer->getObjectKind());
5271 Expr *OVEAsExpr = &OVE;
5272 InitializeFrom(S, Element, Kind, OVEAsExpr, TopLevelOfInitList,
5273 TreatUnavailableAsInvalid);
5275 AddArrayInitLoopStep(Entity.getType(), InitEltT);
5279 // Note: as an GNU C extension, we allow initialization of an
5280 // array from a compound literal that creates an array of the same
5281 // type, so long as the initializer has no side effects.
5282 if (!S.getLangOpts().CPlusPlus && Initializer &&
5283 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) &&
5284 Initializer->getType()->isArrayType()) {
5285 const ArrayType *SourceAT
5286 = Context.getAsArrayType(Initializer->getType());
5287 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT))
5288 SetFailed(FK_ArrayTypeMismatch);
5289 else if (Initializer->HasSideEffects(S.Context))
5290 SetFailed(FK_NonConstantArrayInit);
5292 AddArrayInitStep(DestType, /*IsGNUExtension*/true);
5295 // Note: as a GNU C++ extension, we allow list-initialization of a
5296 // class member of array type from a parenthesized initializer list.
5297 else if (S.getLangOpts().CPlusPlus &&
5298 Entity.getKind() == InitializedEntity::EK_Member &&
5299 Initializer && isa<InitListExpr>(Initializer)) {
5300 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer),
5301 *this, TreatUnavailableAsInvalid);
5302 AddParenthesizedArrayInitStep(DestType);
5303 } else if (DestAT->getElementType()->isCharType())
5304 SetFailed(FK_ArrayNeedsInitListOrStringLiteral);
5305 else if (IsWideCharCompatible(DestAT->getElementType(), Context))
5306 SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral);
5308 SetFailed(FK_ArrayNeedsInitList);
5313 // Determine whether we should consider writeback conversions for
5315 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount &&
5316 Entity.isParameterKind();
5318 // We're at the end of the line for C: it's either a write-back conversion
5319 // or it's a C assignment. There's no need to check anything else.
5320 if (!S.getLangOpts().CPlusPlus) {
5321 // If allowed, check whether this is an Objective-C writeback conversion.
5322 if (allowObjCWritebackConversion &&
5323 tryObjCWritebackConversion(S, *this, Entity, Initializer)) {
5327 if (TryOCLSamplerInitialization(S, *this, DestType, Initializer))
5330 if (TryOCLZeroEventInitialization(S, *this, DestType, Initializer))
5333 if (TryOCLZeroQueueInitialization(S, *this, DestType, Initializer))
5336 // Handle initialization in C
5337 AddCAssignmentStep(DestType);
5338 MaybeProduceObjCObject(S, *this, Entity);
5342 assert(S.getLangOpts().CPlusPlus);
5344 // - If the destination type is a (possibly cv-qualified) class type:
5345 if (DestType->isRecordType()) {
5346 // - If the initialization is direct-initialization, or if it is
5347 // copy-initialization where the cv-unqualified version of the
5348 // source type is the same class as, or a derived class of, the
5349 // class of the destination, constructors are considered. [...]
5350 if (Kind.getKind() == InitializationKind::IK_Direct ||
5351 (Kind.getKind() == InitializationKind::IK_Copy &&
5352 (Context.hasSameUnqualifiedType(SourceType, DestType) ||
5353 S.IsDerivedFrom(Initializer->getLocStart(), SourceType, DestType))))
5354 TryConstructorInitialization(S, Entity, Kind, Args,
5355 DestType, DestType, *this);
5356 // - Otherwise (i.e., for the remaining copy-initialization cases),
5357 // user-defined conversion sequences that can convert from the source
5358 // type to the destination type or (when a conversion function is
5359 // used) to a derived class thereof are enumerated as described in
5360 // 13.3.1.4, and the best one is chosen through overload resolution
5363 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5364 TopLevelOfInitList);
5368 assert(Args.size() >= 1 && "Zero-argument case handled above");
5370 // The remaining cases all need a source type.
5371 if (Args.size() > 1) {
5372 SetFailed(FK_TooManyInitsForScalar);
5374 } else if (isa<InitListExpr>(Args[0])) {
5375 SetFailed(FK_ParenthesizedListInitForScalar);
5379 // - Otherwise, if the source type is a (possibly cv-qualified) class
5380 // type, conversion functions are considered.
5381 if (!SourceType.isNull() && SourceType->isRecordType()) {
5382 // For a conversion to _Atomic(T) from either T or a class type derived
5383 // from T, initialize the T object then convert to _Atomic type.
5384 bool NeedAtomicConversion = false;
5385 if (const AtomicType *Atomic = DestType->getAs<AtomicType>()) {
5386 if (Context.hasSameUnqualifiedType(SourceType, Atomic->getValueType()) ||
5387 S.IsDerivedFrom(Initializer->getLocStart(), SourceType,
5388 Atomic->getValueType())) {
5389 DestType = Atomic->getValueType();
5390 NeedAtomicConversion = true;
5394 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5395 TopLevelOfInitList);
5396 MaybeProduceObjCObject(S, *this, Entity);
5397 if (!Failed() && NeedAtomicConversion)
5398 AddAtomicConversionStep(Entity.getType());
5402 // - Otherwise, the initial value of the object being initialized is the
5403 // (possibly converted) value of the initializer expression. Standard
5404 // conversions (Clause 4) will be used, if necessary, to convert the
5405 // initializer expression to the cv-unqualified version of the
5406 // destination type; no user-defined conversions are considered.
5408 ImplicitConversionSequence ICS
5409 = S.TryImplicitConversion(Initializer, DestType,
5410 /*SuppressUserConversions*/true,
5411 /*AllowExplicitConversions*/ false,
5412 /*InOverloadResolution*/ false,
5413 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
5414 allowObjCWritebackConversion);
5416 if (ICS.isStandard() &&
5417 ICS.Standard.Second == ICK_Writeback_Conversion) {
5418 // Objective-C ARC writeback conversion.
5420 // We should copy unless we're passing to an argument explicitly
5422 bool ShouldCopy = true;
5423 if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
5424 ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
5426 // If there was an lvalue adjustment, add it as a separate conversion.
5427 if (ICS.Standard.First == ICK_Array_To_Pointer ||
5428 ICS.Standard.First == ICK_Lvalue_To_Rvalue) {
5429 ImplicitConversionSequence LvalueICS;
5430 LvalueICS.setStandard();
5431 LvalueICS.Standard.setAsIdentityConversion();
5432 LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0));
5433 LvalueICS.Standard.First = ICS.Standard.First;
5434 AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0));
5437 AddPassByIndirectCopyRestoreStep(DestType, ShouldCopy);
5438 } else if (ICS.isBad()) {
5440 if (isLibstdcxxPointerReturnFalseHack(S, Entity, Initializer)) {
5441 AddZeroInitializationStep(Entity.getType());
5442 } else if (Initializer->getType() == Context.OverloadTy &&
5443 !S.ResolveAddressOfOverloadedFunction(Initializer, DestType,
5445 SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
5446 else if (Initializer->getType()->isFunctionType() &&
5447 isExprAnUnaddressableFunction(S, Initializer))
5448 SetFailed(InitializationSequence::FK_AddressOfUnaddressableFunction);
5450 SetFailed(InitializationSequence::FK_ConversionFailed);
5452 AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
5454 MaybeProduceObjCObject(S, *this, Entity);
5458 InitializationSequence::~InitializationSequence() {
5459 for (auto &S : Steps)
5463 //===----------------------------------------------------------------------===//
5464 // Perform initialization
5465 //===----------------------------------------------------------------------===//
5466 static Sema::AssignmentAction
5467 getAssignmentAction(const InitializedEntity &Entity, bool Diagnose = false) {
5468 switch(Entity.getKind()) {
5469 case InitializedEntity::EK_Variable:
5470 case InitializedEntity::EK_New:
5471 case InitializedEntity::EK_Exception:
5472 case InitializedEntity::EK_Base:
5473 case InitializedEntity::EK_Delegating:
5474 return Sema::AA_Initializing;
5476 case InitializedEntity::EK_Parameter:
5477 if (Entity.getDecl() &&
5478 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
5479 return Sema::AA_Sending;
5481 return Sema::AA_Passing;
5483 case InitializedEntity::EK_Parameter_CF_Audited:
5484 if (Entity.getDecl() &&
5485 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
5486 return Sema::AA_Sending;
5488 return !Diagnose ? Sema::AA_Passing : Sema::AA_Passing_CFAudited;
5490 case InitializedEntity::EK_Result:
5491 return Sema::AA_Returning;
5493 case InitializedEntity::EK_Temporary:
5494 case InitializedEntity::EK_RelatedResult:
5495 // FIXME: Can we tell apart casting vs. converting?
5496 return Sema::AA_Casting;
5498 case InitializedEntity::EK_Member:
5499 case InitializedEntity::EK_Binding:
5500 case InitializedEntity::EK_ArrayElement:
5501 case InitializedEntity::EK_VectorElement:
5502 case InitializedEntity::EK_ComplexElement:
5503 case InitializedEntity::EK_BlockElement:
5504 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
5505 case InitializedEntity::EK_LambdaCapture:
5506 case InitializedEntity::EK_CompoundLiteralInit:
5507 return Sema::AA_Initializing;
5510 llvm_unreachable("Invalid EntityKind!");
5513 /// \brief Whether we should bind a created object as a temporary when
5514 /// initializing the given entity.
5515 static bool shouldBindAsTemporary(const InitializedEntity &Entity) {
5516 switch (Entity.getKind()) {
5517 case InitializedEntity::EK_ArrayElement:
5518 case InitializedEntity::EK_Member:
5519 case InitializedEntity::EK_Result:
5520 case InitializedEntity::EK_New:
5521 case InitializedEntity::EK_Variable:
5522 case InitializedEntity::EK_Base:
5523 case InitializedEntity::EK_Delegating:
5524 case InitializedEntity::EK_VectorElement:
5525 case InitializedEntity::EK_ComplexElement:
5526 case InitializedEntity::EK_Exception:
5527 case InitializedEntity::EK_BlockElement:
5528 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
5529 case InitializedEntity::EK_LambdaCapture:
5530 case InitializedEntity::EK_CompoundLiteralInit:
5533 case InitializedEntity::EK_Parameter:
5534 case InitializedEntity::EK_Parameter_CF_Audited:
5535 case InitializedEntity::EK_Temporary:
5536 case InitializedEntity::EK_RelatedResult:
5537 case InitializedEntity::EK_Binding:
5541 llvm_unreachable("missed an InitializedEntity kind?");
5544 /// \brief Whether the given entity, when initialized with an object
5545 /// created for that initialization, requires destruction.
5546 static bool shouldDestroyEntity(const InitializedEntity &Entity) {
5547 switch (Entity.getKind()) {
5548 case InitializedEntity::EK_Result:
5549 case InitializedEntity::EK_New:
5550 case InitializedEntity::EK_Base:
5551 case InitializedEntity::EK_Delegating:
5552 case InitializedEntity::EK_VectorElement:
5553 case InitializedEntity::EK_ComplexElement:
5554 case InitializedEntity::EK_BlockElement:
5555 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
5556 case InitializedEntity::EK_LambdaCapture:
5559 case InitializedEntity::EK_Member:
5560 case InitializedEntity::EK_Binding:
5561 case InitializedEntity::EK_Variable:
5562 case InitializedEntity::EK_Parameter:
5563 case InitializedEntity::EK_Parameter_CF_Audited:
5564 case InitializedEntity::EK_Temporary:
5565 case InitializedEntity::EK_ArrayElement:
5566 case InitializedEntity::EK_Exception:
5567 case InitializedEntity::EK_CompoundLiteralInit:
5568 case InitializedEntity::EK_RelatedResult:
5572 llvm_unreachable("missed an InitializedEntity kind?");
5575 /// \brief Get the location at which initialization diagnostics should appear.
5576 static SourceLocation getInitializationLoc(const InitializedEntity &Entity,
5577 Expr *Initializer) {
5578 switch (Entity.getKind()) {
5579 case InitializedEntity::EK_Result:
5580 return Entity.getReturnLoc();
5582 case InitializedEntity::EK_Exception:
5583 return Entity.getThrowLoc();
5585 case InitializedEntity::EK_Variable:
5586 case InitializedEntity::EK_Binding:
5587 return Entity.getDecl()->getLocation();
5589 case InitializedEntity::EK_LambdaCapture:
5590 return Entity.getCaptureLoc();
5592 case InitializedEntity::EK_ArrayElement:
5593 case InitializedEntity::EK_Member:
5594 case InitializedEntity::EK_Parameter:
5595 case InitializedEntity::EK_Parameter_CF_Audited:
5596 case InitializedEntity::EK_Temporary:
5597 case InitializedEntity::EK_New:
5598 case InitializedEntity::EK_Base:
5599 case InitializedEntity::EK_Delegating:
5600 case InitializedEntity::EK_VectorElement:
5601 case InitializedEntity::EK_ComplexElement:
5602 case InitializedEntity::EK_BlockElement:
5603 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
5604 case InitializedEntity::EK_CompoundLiteralInit:
5605 case InitializedEntity::EK_RelatedResult:
5606 return Initializer->getLocStart();
5608 llvm_unreachable("missed an InitializedEntity kind?");
5611 /// \brief Make a (potentially elidable) temporary copy of the object
5612 /// provided by the given initializer by calling the appropriate copy
5615 /// \param S The Sema object used for type-checking.
5617 /// \param T The type of the temporary object, which must either be
5618 /// the type of the initializer expression or a superclass thereof.
5620 /// \param Entity The entity being initialized.
5622 /// \param CurInit The initializer expression.
5624 /// \param IsExtraneousCopy Whether this is an "extraneous" copy that
5625 /// is permitted in C++03 (but not C++0x) when binding a reference to
5628 /// \returns An expression that copies the initializer expression into
5629 /// a temporary object, or an error expression if a copy could not be
5631 static ExprResult CopyObject(Sema &S,
5633 const InitializedEntity &Entity,
5635 bool IsExtraneousCopy) {
5636 if (CurInit.isInvalid())
5638 // Determine which class type we're copying to.
5639 Expr *CurInitExpr = (Expr *)CurInit.get();
5640 CXXRecordDecl *Class = nullptr;
5641 if (const RecordType *Record = T->getAs<RecordType>())
5642 Class = cast<CXXRecordDecl>(Record->getDecl());
5646 SourceLocation Loc = getInitializationLoc(Entity, CurInit.get());
5648 // Make sure that the type we are copying is complete.
5649 if (S.RequireCompleteType(Loc, T, diag::err_temp_copy_incomplete))
5652 // Perform overload resolution using the class's constructors. Per
5653 // C++11 [dcl.init]p16, second bullet for class types, this initialization
5654 // is direct-initialization.
5655 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5656 DeclContext::lookup_result Ctors = S.LookupConstructors(Class);
5658 OverloadCandidateSet::iterator Best;
5659 switch (ResolveConstructorOverload(
5660 S, Loc, CurInitExpr, CandidateSet, Ctors, Best,
5661 /*CopyInitializing=*/false, /*AllowExplicit=*/true,
5662 /*OnlyListConstructors=*/false, /*IsListInit=*/false,
5663 /*SecondStepOfCopyInit=*/true)) {
5667 case OR_No_Viable_Function:
5668 S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext()
5669 ? diag::ext_rvalue_to_reference_temp_copy_no_viable
5670 : diag::err_temp_copy_no_viable)
5671 << (int)Entity.getKind() << CurInitExpr->getType()
5672 << CurInitExpr->getSourceRange();
5673 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr);
5674 if (!IsExtraneousCopy || S.isSFINAEContext())
5679 S.Diag(Loc, diag::err_temp_copy_ambiguous)
5680 << (int)Entity.getKind() << CurInitExpr->getType()
5681 << CurInitExpr->getSourceRange();
5682 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr);
5686 S.Diag(Loc, diag::err_temp_copy_deleted)
5687 << (int)Entity.getKind() << CurInitExpr->getType()
5688 << CurInitExpr->getSourceRange();
5689 S.NoteDeletedFunction(Best->Function);
5693 bool HadMultipleCandidates = CandidateSet.size() > 1;
5695 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function);
5696 SmallVector<Expr*, 8> ConstructorArgs;
5697 CurInit.get(); // Ownership transferred into MultiExprArg, below.
5699 S.CheckConstructorAccess(Loc, Constructor, Best->FoundDecl, Entity,
5702 if (IsExtraneousCopy) {
5703 // If this is a totally extraneous copy for C++03 reference
5704 // binding purposes, just return the original initialization
5705 // expression. We don't generate an (elided) copy operation here
5706 // because doing so would require us to pass down a flag to avoid
5707 // infinite recursion, where each step adds another extraneous,
5710 // Instantiate the default arguments of any extra parameters in
5711 // the selected copy constructor, as if we were going to create a
5712 // proper call to the copy constructor.
5713 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) {
5714 ParmVarDecl *Parm = Constructor->getParamDecl(I);
5715 if (S.RequireCompleteType(Loc, Parm->getType(),
5716 diag::err_call_incomplete_argument))
5719 // Build the default argument expression; we don't actually care
5720 // if this succeeds or not, because this routine will complain
5721 // if there was a problem.
5722 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm);
5728 // Determine the arguments required to actually perform the
5729 // constructor call (we might have derived-to-base conversions, or
5730 // the copy constructor may have default arguments).
5731 if (S.CompleteConstructorCall(Constructor, CurInitExpr, Loc, ConstructorArgs))
5734 // C++0x [class.copy]p32:
5735 // When certain criteria are met, an implementation is allowed to
5736 // omit the copy/move construction of a class object, even if the
5737 // copy/move constructor and/or destructor for the object have
5738 // side effects. [...]
5739 // - when a temporary class object that has not been bound to a
5740 // reference (12.2) would be copied/moved to a class object
5741 // with the same cv-unqualified type, the copy/move operation
5742 // can be omitted by constructing the temporary object
5743 // directly into the target of the omitted copy/move
5745 // Note that the other three bullets are handled elsewhere. Copy
5746 // elision for return statements and throw expressions are handled as part
5747 // of constructor initialization, while copy elision for exception handlers
5748 // is handled by the run-time.
5750 // FIXME: If the function parameter is not the same type as the temporary, we
5751 // should still be able to elide the copy, but we don't have a way to
5752 // represent in the AST how much should be elided in this case.
5754 CurInitExpr->isTemporaryObject(S.Context, Class) &&
5755 S.Context.hasSameUnqualifiedType(
5756 Best->Function->getParamDecl(0)->getType().getNonReferenceType(),
5757 CurInitExpr->getType());
5759 // Actually perform the constructor call.
5760 CurInit = S.BuildCXXConstructExpr(Loc, T, Best->FoundDecl, Constructor,
5763 HadMultipleCandidates,
5765 /*StdInitListInit*/ false,
5767 CXXConstructExpr::CK_Complete,
5770 // If we're supposed to bind temporaries, do so.
5771 if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity))
5772 CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
5776 /// \brief Check whether elidable copy construction for binding a reference to
5777 /// a temporary would have succeeded if we were building in C++98 mode, for
5779 static void CheckCXX98CompatAccessibleCopy(Sema &S,
5780 const InitializedEntity &Entity,
5781 Expr *CurInitExpr) {
5782 assert(S.getLangOpts().CPlusPlus11);
5784 const RecordType *Record = CurInitExpr->getType()->getAs<RecordType>();
5788 SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr);
5789 if (S.Diags.isIgnored(diag::warn_cxx98_compat_temp_copy, Loc))
5792 // Find constructors which would have been considered.
5793 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5794 DeclContext::lookup_result Ctors =
5795 S.LookupConstructors(cast<CXXRecordDecl>(Record->getDecl()));
5797 // Perform overload resolution.
5798 OverloadCandidateSet::iterator Best;
5799 OverloadingResult OR = ResolveConstructorOverload(
5800 S, Loc, CurInitExpr, CandidateSet, Ctors, Best,
5801 /*CopyInitializing=*/false, /*AllowExplicit=*/true,
5802 /*OnlyListConstructors=*/false, /*IsListInit=*/false,
5803 /*SecondStepOfCopyInit=*/true);
5805 PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy)
5806 << OR << (int)Entity.getKind() << CurInitExpr->getType()
5807 << CurInitExpr->getSourceRange();
5811 S.CheckConstructorAccess(Loc, cast<CXXConstructorDecl>(Best->Function),
5812 Best->FoundDecl, Entity, Diag);
5813 // FIXME: Check default arguments as far as that's possible.
5816 case OR_No_Viable_Function:
5818 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr);
5823 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr);
5828 S.NoteDeletedFunction(Best->Function);
5833 void InitializationSequence::PrintInitLocationNote(Sema &S,
5834 const InitializedEntity &Entity) {
5835 if (Entity.isParameterKind() && Entity.getDecl()) {
5836 if (Entity.getDecl()->getLocation().isInvalid())
5839 if (Entity.getDecl()->getDeclName())
5840 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here)
5841 << Entity.getDecl()->getDeclName();
5843 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here);
5845 else if (Entity.getKind() == InitializedEntity::EK_RelatedResult &&
5846 Entity.getMethodDecl())
5847 S.Diag(Entity.getMethodDecl()->getLocation(),
5848 diag::note_method_return_type_change)
5849 << Entity.getMethodDecl()->getDeclName();
5852 /// Returns true if the parameters describe a constructor initialization of
5853 /// an explicit temporary object, e.g. "Point(x, y)".
5854 static bool isExplicitTemporary(const InitializedEntity &Entity,
5855 const InitializationKind &Kind,
5857 switch (Entity.getKind()) {
5858 case InitializedEntity::EK_Temporary:
5859 case InitializedEntity::EK_CompoundLiteralInit:
5860 case InitializedEntity::EK_RelatedResult:
5866 switch (Kind.getKind()) {
5867 case InitializationKind::IK_DirectList:
5869 // FIXME: Hack to work around cast weirdness.
5870 case InitializationKind::IK_Direct:
5871 case InitializationKind::IK_Value:
5872 return NumArgs != 1;
5879 PerformConstructorInitialization(Sema &S,
5880 const InitializedEntity &Entity,
5881 const InitializationKind &Kind,
5883 const InitializationSequence::Step& Step,
5884 bool &ConstructorInitRequiresZeroInit,
5885 bool IsListInitialization,
5886 bool IsStdInitListInitialization,
5887 SourceLocation LBraceLoc,
5888 SourceLocation RBraceLoc) {
5889 unsigned NumArgs = Args.size();
5890 CXXConstructorDecl *Constructor
5891 = cast<CXXConstructorDecl>(Step.Function.Function);
5892 bool HadMultipleCandidates = Step.Function.HadMultipleCandidates;
5894 // Build a call to the selected constructor.
5895 SmallVector<Expr*, 8> ConstructorArgs;
5896 SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid())
5897 ? Kind.getEqualLoc()
5898 : Kind.getLocation();
5900 if (Kind.getKind() == InitializationKind::IK_Default) {
5901 // Force even a trivial, implicit default constructor to be
5902 // semantically checked. We do this explicitly because we don't build
5903 // the definition for completely trivial constructors.
5904 assert(Constructor->getParent() && "No parent class for constructor.");
5905 if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
5906 Constructor->isTrivial() && !Constructor->isUsed(false))
5907 S.DefineImplicitDefaultConstructor(Loc, Constructor);
5910 ExprResult CurInit((Expr *)nullptr);
5912 // C++ [over.match.copy]p1:
5913 // - When initializing a temporary to be bound to the first parameter
5914 // of a constructor that takes a reference to possibly cv-qualified
5915 // T as its first argument, called with a single argument in the
5916 // context of direct-initialization, explicit conversion functions
5917 // are also considered.
5918 bool AllowExplicitConv =
5919 Kind.AllowExplicit() && !Kind.isCopyInit() && Args.size() == 1 &&
5920 hasCopyOrMoveCtorParam(S.Context,
5921 getConstructorInfo(Step.Function.FoundDecl));
5923 // Determine the arguments required to actually perform the constructor
5925 if (S.CompleteConstructorCall(Constructor, Args,
5926 Loc, ConstructorArgs,
5928 IsListInitialization))
5932 if (isExplicitTemporary(Entity, Kind, NumArgs)) {
5933 // An explicitly-constructed temporary, e.g., X(1, 2).
5934 if (S.DiagnoseUseOfDecl(Constructor, Loc))
5937 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
5939 TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc);
5940 SourceRange ParenOrBraceRange =
5941 (Kind.getKind() == InitializationKind::IK_DirectList)
5942 ? SourceRange(LBraceLoc, RBraceLoc)
5943 : Kind.getParenRange();
5945 if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(
5946 Step.Function.FoundDecl.getDecl())) {
5947 Constructor = S.findInheritingConstructor(Loc, Constructor, Shadow);
5948 if (S.DiagnoseUseOfDecl(Constructor, Loc))
5951 S.MarkFunctionReferenced(Loc, Constructor);
5953 CurInit = new (S.Context) CXXTemporaryObjectExpr(
5954 S.Context, Constructor,
5955 Entity.getType().getNonLValueExprType(S.Context), TSInfo,
5956 ConstructorArgs, ParenOrBraceRange, HadMultipleCandidates,
5957 IsListInitialization, IsStdInitListInitialization,
5958 ConstructorInitRequiresZeroInit);
5960 CXXConstructExpr::ConstructionKind ConstructKind =
5961 CXXConstructExpr::CK_Complete;
5963 if (Entity.getKind() == InitializedEntity::EK_Base) {
5964 ConstructKind = Entity.getBaseSpecifier()->isVirtual() ?
5965 CXXConstructExpr::CK_VirtualBase :
5966 CXXConstructExpr::CK_NonVirtualBase;
5967 } else if (Entity.getKind() == InitializedEntity::EK_Delegating) {
5968 ConstructKind = CXXConstructExpr::CK_Delegating;
5971 // Only get the parenthesis or brace range if it is a list initialization or
5972 // direct construction.
5973 SourceRange ParenOrBraceRange;
5974 if (IsListInitialization)
5975 ParenOrBraceRange = SourceRange(LBraceLoc, RBraceLoc);
5976 else if (Kind.getKind() == InitializationKind::IK_Direct)
5977 ParenOrBraceRange = Kind.getParenRange();
5979 // If the entity allows NRVO, mark the construction as elidable
5981 if (Entity.allowsNRVO())
5982 CurInit = S.BuildCXXConstructExpr(Loc, Step.Type,
5983 Step.Function.FoundDecl,
5984 Constructor, /*Elidable=*/true,
5986 HadMultipleCandidates,
5987 IsListInitialization,
5988 IsStdInitListInitialization,
5989 ConstructorInitRequiresZeroInit,
5993 CurInit = S.BuildCXXConstructExpr(Loc, Step.Type,
5994 Step.Function.FoundDecl,
5997 HadMultipleCandidates,
5998 IsListInitialization,
5999 IsStdInitListInitialization,
6000 ConstructorInitRequiresZeroInit,
6004 if (CurInit.isInvalid())
6007 // Only check access if all of that succeeded.
6008 S.CheckConstructorAccess(Loc, Constructor, Step.Function.FoundDecl, Entity);
6009 if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc))
6012 if (shouldBindAsTemporary(Entity))
6013 CurInit = S.MaybeBindToTemporary(CurInit.get());
6018 /// Determine whether the specified InitializedEntity definitely has a lifetime
6019 /// longer than the current full-expression. Conservatively returns false if
6022 InitializedEntityOutlivesFullExpression(const InitializedEntity &Entity) {
6023 const InitializedEntity *Top = &Entity;
6024 while (Top->getParent())
6025 Top = Top->getParent();
6027 switch (Top->getKind()) {
6028 case InitializedEntity::EK_Variable:
6029 case InitializedEntity::EK_Result:
6030 case InitializedEntity::EK_Exception:
6031 case InitializedEntity::EK_Member:
6032 case InitializedEntity::EK_Binding:
6033 case InitializedEntity::EK_New:
6034 case InitializedEntity::EK_Base:
6035 case InitializedEntity::EK_Delegating:
6038 case InitializedEntity::EK_ArrayElement:
6039 case InitializedEntity::EK_VectorElement:
6040 case InitializedEntity::EK_BlockElement:
6041 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
6042 case InitializedEntity::EK_ComplexElement:
6043 // Could not determine what the full initialization is. Assume it might not
6044 // outlive the full-expression.
6047 case InitializedEntity::EK_Parameter:
6048 case InitializedEntity::EK_Parameter_CF_Audited:
6049 case InitializedEntity::EK_Temporary:
6050 case InitializedEntity::EK_LambdaCapture:
6051 case InitializedEntity::EK_CompoundLiteralInit:
6052 case InitializedEntity::EK_RelatedResult:
6053 // The entity being initialized might not outlive the full-expression.
6057 llvm_unreachable("unknown entity kind");
6060 /// Determine the declaration which an initialized entity ultimately refers to,
6061 /// for the purpose of lifetime-extending a temporary bound to a reference in
6062 /// the initialization of \p Entity.
6063 static const InitializedEntity *getEntityForTemporaryLifetimeExtension(
6064 const InitializedEntity *Entity,
6065 const InitializedEntity *FallbackDecl = nullptr) {
6066 // C++11 [class.temporary]p5:
6067 switch (Entity->getKind()) {
6068 case InitializedEntity::EK_Variable:
6069 // The temporary [...] persists for the lifetime of the reference
6072 case InitializedEntity::EK_Member:
6073 // For subobjects, we look at the complete object.
6074 if (Entity->getParent())
6075 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
6079 // -- A temporary bound to a reference member in a constructor's
6080 // ctor-initializer persists until the constructor exits.
6083 case InitializedEntity::EK_Binding:
6084 // Per [dcl.decomp]p3, the binding is treated as a variable of reference
6088 case InitializedEntity::EK_Parameter:
6089 case InitializedEntity::EK_Parameter_CF_Audited:
6090 // -- A temporary bound to a reference parameter in a function call
6091 // persists until the completion of the full-expression containing
6093 case InitializedEntity::EK_Result:
6094 // -- The lifetime of a temporary bound to the returned value in a
6095 // function return statement is not extended; the temporary is
6096 // destroyed at the end of the full-expression in the return statement.
6097 case InitializedEntity::EK_New:
6098 // -- A temporary bound to a reference in a new-initializer persists
6099 // until the completion of the full-expression containing the
6103 case InitializedEntity::EK_Temporary:
6104 case InitializedEntity::EK_CompoundLiteralInit:
6105 case InitializedEntity::EK_RelatedResult:
6106 // We don't yet know the storage duration of the surrounding temporary.
6107 // Assume it's got full-expression duration for now, it will patch up our
6108 // storage duration if that's not correct.
6111 case InitializedEntity::EK_ArrayElement:
6112 // For subobjects, we look at the complete object.
6113 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
6116 case InitializedEntity::EK_Base:
6117 // For subobjects, we look at the complete object.
6118 if (Entity->getParent())
6119 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
6122 case InitializedEntity::EK_Delegating:
6123 // We can reach this case for aggregate initialization in a constructor:
6124 // struct A { int &&r; };
6125 // struct B : A { B() : A{0} {} };
6126 // In this case, use the innermost field decl as the context.
6127 return FallbackDecl;
6129 case InitializedEntity::EK_BlockElement:
6130 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
6131 case InitializedEntity::EK_LambdaCapture:
6132 case InitializedEntity::EK_Exception:
6133 case InitializedEntity::EK_VectorElement:
6134 case InitializedEntity::EK_ComplexElement:
6137 llvm_unreachable("unknown entity kind");
6140 static void performLifetimeExtension(Expr *Init,
6141 const InitializedEntity *ExtendingEntity);
6143 /// Update a glvalue expression that is used as the initializer of a reference
6144 /// to note that its lifetime is extended.
6145 /// \return \c true if any temporary had its lifetime extended.
6147 performReferenceExtension(Expr *Init,
6148 const InitializedEntity *ExtendingEntity) {
6149 // Walk past any constructs which we can lifetime-extend across.
6154 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
6155 if (ILE->getNumInits() == 1 && ILE->isGLValue()) {
6156 // This is just redundant braces around an initializer. Step over it.
6157 Init = ILE->getInit(0);
6161 // Step over any subobject adjustments; we may have a materialized
6162 // temporary inside them.
6163 Init = const_cast<Expr *>(Init->skipRValueSubobjectAdjustments());
6165 // Per current approach for DR1376, look through casts to reference type
6166 // when performing lifetime extension.
6167 if (CastExpr *CE = dyn_cast<CastExpr>(Init))
6168 if (CE->getSubExpr()->isGLValue())
6169 Init = CE->getSubExpr();
6171 // Per the current approach for DR1299, look through array element access
6172 // when performing lifetime extension.
6173 if (auto *ASE = dyn_cast<ArraySubscriptExpr>(Init))
6174 Init = ASE->getBase();
6175 } while (Init != Old);
6177 if (MaterializeTemporaryExpr *ME = dyn_cast<MaterializeTemporaryExpr>(Init)) {
6178 // Update the storage duration of the materialized temporary.
6179 // FIXME: Rebuild the expression instead of mutating it.
6180 ME->setExtendingDecl(ExtendingEntity->getDecl(),
6181 ExtendingEntity->allocateManglingNumber());
6182 performLifetimeExtension(ME->GetTemporaryExpr(), ExtendingEntity);
6189 /// Update a prvalue expression that is going to be materialized as a
6190 /// lifetime-extended temporary.
6191 static void performLifetimeExtension(Expr *Init,
6192 const InitializedEntity *ExtendingEntity) {
6193 // Dig out the expression which constructs the extended temporary.
6194 Init = const_cast<Expr *>(Init->skipRValueSubobjectAdjustments());
6196 if (CXXBindTemporaryExpr *BTE = dyn_cast<CXXBindTemporaryExpr>(Init))
6197 Init = BTE->getSubExpr();
6199 if (CXXStdInitializerListExpr *ILE =
6200 dyn_cast<CXXStdInitializerListExpr>(Init)) {
6201 performReferenceExtension(ILE->getSubExpr(), ExtendingEntity);
6205 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
6206 if (ILE->getType()->isArrayType()) {
6207 for (unsigned I = 0, N = ILE->getNumInits(); I != N; ++I)
6208 performLifetimeExtension(ILE->getInit(I), ExtendingEntity);
6212 if (CXXRecordDecl *RD = ILE->getType()->getAsCXXRecordDecl()) {
6213 assert(RD->isAggregate() && "aggregate init on non-aggregate");
6215 // If we lifetime-extend a braced initializer which is initializing an
6216 // aggregate, and that aggregate contains reference members which are
6217 // bound to temporaries, those temporaries are also lifetime-extended.
6218 if (RD->isUnion() && ILE->getInitializedFieldInUnion() &&
6219 ILE->getInitializedFieldInUnion()->getType()->isReferenceType())
6220 performReferenceExtension(ILE->getInit(0), ExtendingEntity);
6223 for (const auto *I : RD->fields()) {
6224 if (Index >= ILE->getNumInits())
6226 if (I->isUnnamedBitfield())
6228 Expr *SubInit = ILE->getInit(Index);
6229 if (I->getType()->isReferenceType())
6230 performReferenceExtension(SubInit, ExtendingEntity);
6231 else if (isa<InitListExpr>(SubInit) ||
6232 isa<CXXStdInitializerListExpr>(SubInit))
6233 // This may be either aggregate-initialization of a member or
6234 // initialization of a std::initializer_list object. Either way,
6235 // we should recursively lifetime-extend that initializer.
6236 performLifetimeExtension(SubInit, ExtendingEntity);
6244 static void warnOnLifetimeExtension(Sema &S, const InitializedEntity &Entity,
6245 const Expr *Init, bool IsInitializerList,
6246 const ValueDecl *ExtendingDecl) {
6247 // Warn if a field lifetime-extends a temporary.
6248 if (isa<FieldDecl>(ExtendingDecl)) {
6249 if (IsInitializerList) {
6250 S.Diag(Init->getExprLoc(), diag::warn_dangling_std_initializer_list)
6251 << /*at end of constructor*/true;
6255 bool IsSubobjectMember = false;
6256 for (const InitializedEntity *Ent = Entity.getParent(); Ent;
6257 Ent = Ent->getParent()) {
6258 if (Ent->getKind() != InitializedEntity::EK_Base) {
6259 IsSubobjectMember = true;
6263 S.Diag(Init->getExprLoc(),
6264 diag::warn_bind_ref_member_to_temporary)
6265 << ExtendingDecl << Init->getSourceRange()
6266 << IsSubobjectMember << IsInitializerList;
6267 if (IsSubobjectMember)
6268 S.Diag(ExtendingDecl->getLocation(),
6269 diag::note_ref_subobject_of_member_declared_here);
6271 S.Diag(ExtendingDecl->getLocation(),
6272 diag::note_ref_or_ptr_member_declared_here)
6273 << /*is pointer*/false;
6277 static void DiagnoseNarrowingInInitList(Sema &S,
6278 const ImplicitConversionSequence &ICS,
6279 QualType PreNarrowingType,
6280 QualType EntityType,
6281 const Expr *PostInit);
6283 /// Provide warnings when std::move is used on construction.
6284 static void CheckMoveOnConstruction(Sema &S, const Expr *InitExpr,
6285 bool IsReturnStmt) {
6289 if (S.inTemplateInstantiation())
6292 QualType DestType = InitExpr->getType();
6293 if (!DestType->isRecordType())
6296 unsigned DiagID = 0;
6298 const CXXConstructExpr *CCE =
6299 dyn_cast<CXXConstructExpr>(InitExpr->IgnoreParens());
6300 if (!CCE || CCE->getNumArgs() != 1)
6303 if (!CCE->getConstructor()->isCopyOrMoveConstructor())
6306 InitExpr = CCE->getArg(0)->IgnoreImpCasts();
6309 // Find the std::move call and get the argument.
6310 const CallExpr *CE = dyn_cast<CallExpr>(InitExpr->IgnoreParens());
6311 if (!CE || CE->getNumArgs() != 1)
6314 const FunctionDecl *MoveFunction = CE->getDirectCallee();
6315 if (!MoveFunction || !MoveFunction->isInStdNamespace() ||
6316 !MoveFunction->getIdentifier() ||
6317 !MoveFunction->getIdentifier()->isStr("move"))
6320 const Expr *Arg = CE->getArg(0)->IgnoreImplicit();
6323 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg->IgnoreParenImpCasts());
6324 if (!DRE || DRE->refersToEnclosingVariableOrCapture())
6327 const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl());
6328 if (!VD || !VD->hasLocalStorage())
6331 QualType SourceType = VD->getType();
6332 if (!SourceType->isRecordType())
6335 if (!S.Context.hasSameUnqualifiedType(DestType, SourceType)) {
6339 // If we're returning a function parameter, copy elision
6341 if (isa<ParmVarDecl>(VD))
6342 DiagID = diag::warn_redundant_move_on_return;
6344 DiagID = diag::warn_pessimizing_move_on_return;
6346 DiagID = diag::warn_pessimizing_move_on_initialization;
6347 const Expr *ArgStripped = Arg->IgnoreImplicit()->IgnoreParens();
6348 if (!ArgStripped->isRValue() || !ArgStripped->getType()->isRecordType())
6352 S.Diag(CE->getLocStart(), DiagID);
6354 // Get all the locations for a fix-it. Don't emit the fix-it if any location
6355 // is within a macro.
6356 SourceLocation CallBegin = CE->getCallee()->getLocStart();
6357 if (CallBegin.isMacroID())
6359 SourceLocation RParen = CE->getRParenLoc();
6360 if (RParen.isMacroID())
6362 SourceLocation LParen;
6363 SourceLocation ArgLoc = Arg->getLocStart();
6365 // Special testing for the argument location. Since the fix-it needs the
6366 // location right before the argument, the argument location can be in a
6367 // macro only if it is at the beginning of the macro.
6368 while (ArgLoc.isMacroID() &&
6369 S.getSourceManager().isAtStartOfImmediateMacroExpansion(ArgLoc)) {
6370 ArgLoc = S.getSourceManager().getImmediateExpansionRange(ArgLoc).first;
6373 if (LParen.isMacroID())
6376 LParen = ArgLoc.getLocWithOffset(-1);
6378 S.Diag(CE->getLocStart(), diag::note_remove_move)
6379 << FixItHint::CreateRemoval(SourceRange(CallBegin, LParen))
6380 << FixItHint::CreateRemoval(SourceRange(RParen, RParen));
6383 static void CheckForNullPointerDereference(Sema &S, const Expr *E) {
6384 // Check to see if we are dereferencing a null pointer. If so, this is
6385 // undefined behavior, so warn about it. This only handles the pattern
6386 // "*null", which is a very syntactic check.
6387 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts()))
6388 if (UO->getOpcode() == UO_Deref &&
6389 UO->getSubExpr()->IgnoreParenCasts()->
6390 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull)) {
6391 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
6392 S.PDiag(diag::warn_binding_null_to_reference)
6393 << UO->getSubExpr()->getSourceRange());
6397 MaterializeTemporaryExpr *
6398 Sema::CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary,
6399 bool BoundToLvalueReference) {
6400 auto MTE = new (Context)
6401 MaterializeTemporaryExpr(T, Temporary, BoundToLvalueReference);
6403 // Order an ExprWithCleanups for lifetime marks.
6405 // TODO: It'll be good to have a single place to check the access of the
6406 // destructor and generate ExprWithCleanups for various uses. Currently these
6407 // are done in both CreateMaterializeTemporaryExpr and MaybeBindToTemporary,
6408 // but there may be a chance to merge them.
6409 Cleanup.setExprNeedsCleanups(false);
6413 ExprResult Sema::TemporaryMaterializationConversion(Expr *E) {
6414 // In C++98, we don't want to implicitly create an xvalue.
6415 // FIXME: This means that AST consumers need to deal with "prvalues" that
6416 // denote materialized temporaries. Maybe we should add another ValueKind
6417 // for "xvalue pretending to be a prvalue" for C++98 support.
6418 if (!E->isRValue() || !getLangOpts().CPlusPlus11)
6421 // C++1z [conv.rval]/1: T shall be a complete type.
6422 // FIXME: Does this ever matter (can we form a prvalue of incomplete type)?
6423 // If so, we should check for a non-abstract class type here too.
6424 QualType T = E->getType();
6425 if (RequireCompleteType(E->getExprLoc(), T, diag::err_incomplete_type))
6428 return CreateMaterializeTemporaryExpr(E->getType(), E, false);
6432 InitializationSequence::Perform(Sema &S,
6433 const InitializedEntity &Entity,
6434 const InitializationKind &Kind,
6436 QualType *ResultType) {
6438 Diagnose(S, Entity, Kind, Args);
6441 if (!ZeroInitializationFixit.empty()) {
6442 unsigned DiagID = diag::err_default_init_const;
6443 if (Decl *D = Entity.getDecl())
6444 if (S.getLangOpts().MSVCCompat && D->hasAttr<SelectAnyAttr>())
6445 DiagID = diag::ext_default_init_const;
6447 // The initialization would have succeeded with this fixit. Since the fixit
6448 // is on the error, we need to build a valid AST in this case, so this isn't
6449 // handled in the Failed() branch above.
6450 QualType DestType = Entity.getType();
6451 S.Diag(Kind.getLocation(), DiagID)
6452 << DestType << (bool)DestType->getAs<RecordType>()
6453 << FixItHint::CreateInsertion(ZeroInitializationFixitLoc,
6454 ZeroInitializationFixit);
6457 if (getKind() == DependentSequence) {
6458 // If the declaration is a non-dependent, incomplete array type
6459 // that has an initializer, then its type will be completed once
6460 // the initializer is instantiated.
6461 if (ResultType && !Entity.getType()->isDependentType() &&
6463 QualType DeclType = Entity.getType();
6464 if (const IncompleteArrayType *ArrayT
6465 = S.Context.getAsIncompleteArrayType(DeclType)) {
6466 // FIXME: We don't currently have the ability to accurately
6467 // compute the length of an initializer list without
6468 // performing full type-checking of the initializer list
6469 // (since we have to determine where braces are implicitly
6470 // introduced and such). So, we fall back to making the array
6471 // type a dependently-sized array type with no specified
6473 if (isa<InitListExpr>((Expr *)Args[0])) {
6474 SourceRange Brackets;
6476 // Scavange the location of the brackets from the entity, if we can.
6477 if (auto *DD = dyn_cast_or_null<DeclaratorDecl>(Entity.getDecl())) {
6478 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) {
6479 TypeLoc TL = TInfo->getTypeLoc();
6480 if (IncompleteArrayTypeLoc ArrayLoc =
6481 TL.getAs<IncompleteArrayTypeLoc>())
6482 Brackets = ArrayLoc.getBracketsRange();
6487 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(),
6488 /*NumElts=*/nullptr,
6489 ArrayT->getSizeModifier(),
6490 ArrayT->getIndexTypeCVRQualifiers(),
6496 if (Kind.getKind() == InitializationKind::IK_Direct &&
6497 !Kind.isExplicitCast()) {
6498 // Rebuild the ParenListExpr.
6499 SourceRange ParenRange = Kind.getParenRange();
6500 return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(),
6503 assert(Kind.getKind() == InitializationKind::IK_Copy ||
6504 Kind.isExplicitCast() ||
6505 Kind.getKind() == InitializationKind::IK_DirectList);
6506 return ExprResult(Args[0]);
6509 // No steps means no initialization.
6511 return ExprResult((Expr *)nullptr);
6513 if (S.getLangOpts().CPlusPlus11 && Entity.getType()->isReferenceType() &&
6514 Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
6515 !Entity.isParameterKind()) {
6516 // Produce a C++98 compatibility warning if we are initializing a reference
6517 // from an initializer list. For parameters, we produce a better warning
6519 Expr *Init = Args[0];
6520 S.Diag(Init->getLocStart(), diag::warn_cxx98_compat_reference_list_init)
6521 << Init->getSourceRange();
6524 // OpenCL v2.0 s6.13.11.1. atomic variables can be initialized in global scope
6525 QualType ETy = Entity.getType();
6526 Qualifiers TyQualifiers = ETy.getQualifiers();
6527 bool HasGlobalAS = TyQualifiers.hasAddressSpace() &&
6528 TyQualifiers.getAddressSpace() == LangAS::opencl_global;
6530 if (S.getLangOpts().OpenCLVersion >= 200 &&
6531 ETy->isAtomicType() && !HasGlobalAS &&
6532 Entity.getKind() == InitializedEntity::EK_Variable && Args.size() > 0) {
6533 S.Diag(Args[0]->getLocStart(), diag::err_opencl_atomic_init) << 1 <<
6534 SourceRange(Entity.getDecl()->getLocStart(), Args[0]->getLocEnd());
6538 // Diagnose cases where we initialize a pointer to an array temporary, and the
6539 // pointer obviously outlives the temporary.
6540 if (Args.size() == 1 && Args[0]->getType()->isArrayType() &&
6541 Entity.getType()->isPointerType() &&
6542 InitializedEntityOutlivesFullExpression(Entity)) {
6543 const Expr *Init = Args[0]->skipRValueSubobjectAdjustments();
6544 if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Init))
6545 Init = MTE->GetTemporaryExpr();
6546 Expr::LValueClassification Kind = Init->ClassifyLValue(S.Context);
6547 if (Kind == Expr::LV_ClassTemporary || Kind == Expr::LV_ArrayTemporary)
6548 S.Diag(Init->getLocStart(), diag::warn_temporary_array_to_pointer_decay)
6549 << Init->getSourceRange();
6552 QualType DestType = Entity.getType().getNonReferenceType();
6553 // FIXME: Ugly hack around the fact that Entity.getType() is not
6554 // the same as Entity.getDecl()->getType() in cases involving type merging,
6555 // and we want latter when it makes sense.
6557 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() :
6560 ExprResult CurInit((Expr *)nullptr);
6561 SmallVector<Expr*, 4> ArrayLoopCommonExprs;
6563 // For initialization steps that start with a single initializer,
6564 // grab the only argument out the Args and place it into the "current"
6566 switch (Steps.front().Kind) {
6567 case SK_ResolveAddressOfOverloadedFunction:
6568 case SK_CastDerivedToBaseRValue:
6569 case SK_CastDerivedToBaseXValue:
6570 case SK_CastDerivedToBaseLValue:
6571 case SK_BindReference:
6572 case SK_BindReferenceToTemporary:
6574 case SK_ExtraneousCopyToTemporary:
6575 case SK_UserConversion:
6576 case SK_QualificationConversionLValue:
6577 case SK_QualificationConversionXValue:
6578 case SK_QualificationConversionRValue:
6579 case SK_AtomicConversion:
6580 case SK_LValueToRValue:
6581 case SK_ConversionSequence:
6582 case SK_ConversionSequenceNoNarrowing:
6583 case SK_ListInitialization:
6584 case SK_UnwrapInitList:
6585 case SK_RewrapInitList:
6586 case SK_CAssignment:
6588 case SK_ObjCObjectConversion:
6589 case SK_ArrayLoopIndex:
6590 case SK_ArrayLoopInit:
6592 case SK_GNUArrayInit:
6593 case SK_ParenthesizedArrayInit:
6594 case SK_PassByIndirectCopyRestore:
6595 case SK_PassByIndirectRestore:
6596 case SK_ProduceObjCObject:
6597 case SK_StdInitializerList:
6598 case SK_OCLSamplerInit:
6599 case SK_OCLZeroEvent:
6600 case SK_OCLZeroQueue: {
6601 assert(Args.size() == 1);
6603 if (!CurInit.get()) return ExprError();
6607 case SK_ConstructorInitialization:
6608 case SK_ConstructorInitializationFromList:
6609 case SK_StdInitializerListConstructorCall:
6610 case SK_ZeroInitialization:
6614 // Promote from an unevaluated context to an unevaluated list context in
6615 // C++11 list-initialization; we need to instantiate entities usable in
6616 // constant expressions here in order to perform narrowing checks =(
6617 EnterExpressionEvaluationContext Evaluated(
6618 S, EnterExpressionEvaluationContext::InitList,
6619 CurInit.get() && isa<InitListExpr>(CurInit.get()));
6621 // C++ [class.abstract]p2:
6622 // no objects of an abstract class can be created except as subobjects
6623 // of a class derived from it
6624 auto checkAbstractType = [&](QualType T) -> bool {
6625 if (Entity.getKind() == InitializedEntity::EK_Base ||
6626 Entity.getKind() == InitializedEntity::EK_Delegating)
6628 return S.RequireNonAbstractType(Kind.getLocation(), T,
6629 diag::err_allocation_of_abstract_type);
6632 // Walk through the computed steps for the initialization sequence,
6633 // performing the specified conversions along the way.
6634 bool ConstructorInitRequiresZeroInit = false;
6635 for (step_iterator Step = step_begin(), StepEnd = step_end();
6636 Step != StepEnd; ++Step) {
6637 if (CurInit.isInvalid())
6640 QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType();
6642 switch (Step->Kind) {
6643 case SK_ResolveAddressOfOverloadedFunction:
6644 // Overload resolution determined which function invoke; update the
6645 // initializer to reflect that choice.
6646 S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl);
6647 if (S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()))
6649 CurInit = S.FixOverloadedFunctionReference(CurInit,
6650 Step->Function.FoundDecl,
6651 Step->Function.Function);
6654 case SK_CastDerivedToBaseRValue:
6655 case SK_CastDerivedToBaseXValue:
6656 case SK_CastDerivedToBaseLValue: {
6657 // We have a derived-to-base cast that produces either an rvalue or an
6658 // lvalue. Perform that cast.
6660 CXXCastPath BasePath;
6662 // Casts to inaccessible base classes are allowed with C-style casts.
6663 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast();
6664 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type,
6665 CurInit.get()->getLocStart(),
6666 CurInit.get()->getSourceRange(),
6667 &BasePath, IgnoreBaseAccess))
6671 Step->Kind == SK_CastDerivedToBaseLValue ?
6673 (Step->Kind == SK_CastDerivedToBaseXValue ?
6677 ImplicitCastExpr::Create(S.Context, Step->Type, CK_DerivedToBase,
6678 CurInit.get(), &BasePath, VK);
6682 case SK_BindReference:
6683 // Reference binding does not have any corresponding ASTs.
6685 // Check exception specifications
6686 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
6689 // We don't check for e.g. function pointers here, since address
6690 // availability checks should only occur when the function first decays
6691 // into a pointer or reference.
6692 if (CurInit.get()->getType()->isFunctionProtoType()) {
6693 if (auto *DRE = dyn_cast<DeclRefExpr>(CurInit.get()->IgnoreParens())) {
6694 if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
6695 if (!S.checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
6696 DRE->getLocStart()))
6702 // Even though we didn't materialize a temporary, the binding may still
6703 // extend the lifetime of a temporary. This happens if we bind a reference
6704 // to the result of a cast to reference type.
6705 if (const InitializedEntity *ExtendingEntity =
6706 getEntityForTemporaryLifetimeExtension(&Entity))
6707 if (performReferenceExtension(CurInit.get(), ExtendingEntity))
6708 warnOnLifetimeExtension(S, Entity, CurInit.get(),
6709 /*IsInitializerList=*/false,
6710 ExtendingEntity->getDecl());
6712 CheckForNullPointerDereference(S, CurInit.get());
6715 case SK_BindReferenceToTemporary: {
6716 // Make sure the "temporary" is actually an rvalue.
6717 assert(CurInit.get()->isRValue() && "not a temporary");
6719 // Check exception specifications
6720 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
6723 // Materialize the temporary into memory.
6724 MaterializeTemporaryExpr *MTE = S.CreateMaterializeTemporaryExpr(
6725 Step->Type, CurInit.get(), Entity.getType()->isLValueReferenceType());
6727 // Maybe lifetime-extend the temporary's subobjects to match the
6728 // entity's lifetime.
6729 if (const InitializedEntity *ExtendingEntity =
6730 getEntityForTemporaryLifetimeExtension(&Entity))
6731 if (performReferenceExtension(MTE, ExtendingEntity))
6732 warnOnLifetimeExtension(S, Entity, CurInit.get(),
6733 /*IsInitializerList=*/false,
6734 ExtendingEntity->getDecl());
6736 // If we're extending this temporary to automatic storage duration -- we
6737 // need to register its cleanup during the full-expression's cleanups.
6738 if (MTE->getStorageDuration() == SD_Automatic &&
6739 MTE->getType().isDestructedType())
6740 S.Cleanup.setExprNeedsCleanups(true);
6747 if (checkAbstractType(Step->Type))
6750 // If the overall initialization is initializing a temporary, we already
6751 // bound our argument if it was necessary to do so. If not (if we're
6752 // ultimately initializing a non-temporary), our argument needs to be
6753 // bound since it's initializing a function parameter.
6754 // FIXME: This is a mess. Rationalize temporary destruction.
6755 if (!shouldBindAsTemporary(Entity))
6756 CurInit = S.MaybeBindToTemporary(CurInit.get());
6757 CurInit = CopyObject(S, Step->Type, Entity, CurInit,
6758 /*IsExtraneousCopy=*/false);
6761 case SK_ExtraneousCopyToTemporary:
6762 CurInit = CopyObject(S, Step->Type, Entity, CurInit,
6763 /*IsExtraneousCopy=*/true);
6766 case SK_UserConversion: {
6767 // We have a user-defined conversion that invokes either a constructor
6768 // or a conversion function.
6770 FunctionDecl *Fn = Step->Function.Function;
6771 DeclAccessPair FoundFn = Step->Function.FoundDecl;
6772 bool HadMultipleCandidates = Step->Function.HadMultipleCandidates;
6773 bool CreatedObject = false;
6774 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) {
6775 // Build a call to the selected constructor.
6776 SmallVector<Expr*, 8> ConstructorArgs;
6777 SourceLocation Loc = CurInit.get()->getLocStart();
6779 // Determine the arguments required to actually perform the constructor
6781 Expr *Arg = CurInit.get();
6782 if (S.CompleteConstructorCall(Constructor,
6783 MultiExprArg(&Arg, 1),
6784 Loc, ConstructorArgs))
6787 // Build an expression that constructs a temporary.
6788 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type,
6789 FoundFn, Constructor,
6791 HadMultipleCandidates,
6793 /*StdInitListInit*/ false,
6795 CXXConstructExpr::CK_Complete,
6797 if (CurInit.isInvalid())
6800 S.CheckConstructorAccess(Kind.getLocation(), Constructor, FoundFn,
6802 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
6805 CastKind = CK_ConstructorConversion;
6806 CreatedObject = true;
6808 // Build a call to the conversion function.
6809 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn);
6810 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), nullptr,
6812 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
6815 // FIXME: Should we move this initialization into a separate
6816 // derived-to-base conversion? I believe the answer is "no", because
6817 // we don't want to turn off access control here for c-style casts.
6818 CurInit = S.PerformObjectArgumentInitialization(CurInit.get(),
6819 /*Qualifier=*/nullptr,
6820 FoundFn, Conversion);
6821 if (CurInit.isInvalid())
6824 // Build the actual call to the conversion function.
6825 CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion,
6826 HadMultipleCandidates);
6827 if (CurInit.isInvalid())
6830 CastKind = CK_UserDefinedConversion;
6831 CreatedObject = Conversion->getReturnType()->isRecordType();
6834 if (CreatedObject && checkAbstractType(CurInit.get()->getType()))
6837 CurInit = ImplicitCastExpr::Create(S.Context, CurInit.get()->getType(),
6838 CastKind, CurInit.get(), nullptr,
6839 CurInit.get()->getValueKind());
6841 if (shouldBindAsTemporary(Entity))
6842 // The overall entity is temporary, so this expression should be
6843 // destroyed at the end of its full-expression.
6844 CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
6845 else if (CreatedObject && shouldDestroyEntity(Entity)) {
6846 // The object outlasts the full-expression, but we need to prepare for
6847 // a destructor being run on it.
6848 // FIXME: It makes no sense to do this here. This should happen
6849 // regardless of how we initialized the entity.
6850 QualType T = CurInit.get()->getType();
6851 if (const RecordType *Record = T->getAs<RecordType>()) {
6852 CXXDestructorDecl *Destructor
6853 = S.LookupDestructor(cast<CXXRecordDecl>(Record->getDecl()));
6854 S.CheckDestructorAccess(CurInit.get()->getLocStart(), Destructor,
6855 S.PDiag(diag::err_access_dtor_temp) << T);
6856 S.MarkFunctionReferenced(CurInit.get()->getLocStart(), Destructor);
6857 if (S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getLocStart()))
6864 case SK_QualificationConversionLValue:
6865 case SK_QualificationConversionXValue:
6866 case SK_QualificationConversionRValue: {
6867 // Perform a qualification conversion; these can never go wrong.
6869 Step->Kind == SK_QualificationConversionLValue ?
6871 (Step->Kind == SK_QualificationConversionXValue ?
6874 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type, CK_NoOp, VK);
6878 case SK_AtomicConversion: {
6879 assert(CurInit.get()->isRValue() && "cannot convert glvalue to atomic");
6880 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
6881 CK_NonAtomicToAtomic, VK_RValue);
6885 case SK_LValueToRValue: {
6886 assert(CurInit.get()->isGLValue() && "cannot load from a prvalue");
6887 CurInit = ImplicitCastExpr::Create(S.Context, Step->Type,
6888 CK_LValueToRValue, CurInit.get(),
6889 /*BasePath=*/nullptr, VK_RValue);
6893 case SK_ConversionSequence:
6894 case SK_ConversionSequenceNoNarrowing: {
6895 Sema::CheckedConversionKind CCK
6896 = Kind.isCStyleCast()? Sema::CCK_CStyleCast
6897 : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast
6898 : Kind.isExplicitCast()? Sema::CCK_OtherCast
6899 : Sema::CCK_ImplicitConversion;
6900 ExprResult CurInitExprRes =
6901 S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS,
6902 getAssignmentAction(Entity), CCK);
6903 if (CurInitExprRes.isInvalid())
6906 S.DiscardMisalignedMemberAddress(Step->Type.getTypePtr(), CurInit.get());
6908 CurInit = CurInitExprRes;
6910 if (Step->Kind == SK_ConversionSequenceNoNarrowing &&
6911 S.getLangOpts().CPlusPlus)
6912 DiagnoseNarrowingInInitList(S, *Step->ICS, SourceType, Entity.getType(),
6918 case SK_ListInitialization: {
6919 if (checkAbstractType(Step->Type))
6922 InitListExpr *InitList = cast<InitListExpr>(CurInit.get());
6923 // If we're not initializing the top-level entity, we need to create an
6924 // InitializeTemporary entity for our target type.
6925 QualType Ty = Step->Type;
6926 bool IsTemporary = !S.Context.hasSameType(Entity.getType(), Ty);
6927 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty);
6928 InitializedEntity InitEntity = IsTemporary ? TempEntity : Entity;
6929 InitListChecker PerformInitList(S, InitEntity,
6930 InitList, Ty, /*VerifyOnly=*/false,
6931 /*TreatUnavailableAsInvalid=*/false);
6932 if (PerformInitList.HadError())
6935 // Hack: We must update *ResultType if available in order to set the
6936 // bounds of arrays, e.g. in 'int ar[] = {1, 2, 3};'.
6937 // Worst case: 'const int (&arref)[] = {1, 2, 3};'.
6939 ResultType->getNonReferenceType()->isIncompleteArrayType()) {
6940 if ((*ResultType)->isRValueReferenceType())
6941 Ty = S.Context.getRValueReferenceType(Ty);
6942 else if ((*ResultType)->isLValueReferenceType())
6943 Ty = S.Context.getLValueReferenceType(Ty,
6944 (*ResultType)->getAs<LValueReferenceType>()->isSpelledAsLValue());
6948 InitListExpr *StructuredInitList =
6949 PerformInitList.getFullyStructuredList();
6951 CurInit = shouldBindAsTemporary(InitEntity)
6952 ? S.MaybeBindToTemporary(StructuredInitList)
6953 : StructuredInitList;
6957 case SK_ConstructorInitializationFromList: {
6958 if (checkAbstractType(Step->Type))
6961 // When an initializer list is passed for a parameter of type "reference
6962 // to object", we don't get an EK_Temporary entity, but instead an
6963 // EK_Parameter entity with reference type.
6964 // FIXME: This is a hack. What we really should do is create a user
6965 // conversion step for this case, but this makes it considerably more
6966 // complicated. For now, this will do.
6967 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
6968 Entity.getType().getNonReferenceType());
6969 bool UseTemporary = Entity.getType()->isReferenceType();
6970 assert(Args.size() == 1 && "expected a single argument for list init");
6971 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
6972 S.Diag(InitList->getExprLoc(), diag::warn_cxx98_compat_ctor_list_init)
6973 << InitList->getSourceRange();
6974 MultiExprArg Arg(InitList->getInits(), InitList->getNumInits());
6975 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity :
6978 ConstructorInitRequiresZeroInit,
6979 /*IsListInitialization*/true,
6980 /*IsStdInitListInit*/false,
6981 InitList->getLBraceLoc(),
6982 InitList->getRBraceLoc());
6986 case SK_UnwrapInitList:
6987 CurInit = cast<InitListExpr>(CurInit.get())->getInit(0);
6990 case SK_RewrapInitList: {
6991 Expr *E = CurInit.get();
6992 InitListExpr *Syntactic = Step->WrappingSyntacticList;
6993 InitListExpr *ILE = new (S.Context) InitListExpr(S.Context,
6994 Syntactic->getLBraceLoc(), E, Syntactic->getRBraceLoc());
6995 ILE->setSyntacticForm(Syntactic);
6996 ILE->setType(E->getType());
6997 ILE->setValueKind(E->getValueKind());
7002 case SK_ConstructorInitialization:
7003 case SK_StdInitializerListConstructorCall: {
7004 if (checkAbstractType(Step->Type))
7007 // When an initializer list is passed for a parameter of type "reference
7008 // to object", we don't get an EK_Temporary entity, but instead an
7009 // EK_Parameter entity with reference type.
7010 // FIXME: This is a hack. What we really should do is create a user
7011 // conversion step for this case, but this makes it considerably more
7012 // complicated. For now, this will do.
7013 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
7014 Entity.getType().getNonReferenceType());
7015 bool UseTemporary = Entity.getType()->isReferenceType();
7016 bool IsStdInitListInit =
7017 Step->Kind == SK_StdInitializerListConstructorCall;
7018 Expr *Source = CurInit.get();
7019 CurInit = PerformConstructorInitialization(
7020 S, UseTemporary ? TempEntity : Entity, Kind,
7021 Source ? MultiExprArg(Source) : Args, *Step,
7022 ConstructorInitRequiresZeroInit,
7023 /*IsListInitialization*/ IsStdInitListInit,
7024 /*IsStdInitListInitialization*/ IsStdInitListInit,
7025 /*LBraceLoc*/ SourceLocation(),
7026 /*RBraceLoc*/ SourceLocation());
7030 case SK_ZeroInitialization: {
7031 step_iterator NextStep = Step;
7033 if (NextStep != StepEnd &&
7034 (NextStep->Kind == SK_ConstructorInitialization ||
7035 NextStep->Kind == SK_ConstructorInitializationFromList)) {
7036 // The need for zero-initialization is recorded directly into
7037 // the call to the object's constructor within the next step.
7038 ConstructorInitRequiresZeroInit = true;
7039 } else if (Kind.getKind() == InitializationKind::IK_Value &&
7040 S.getLangOpts().CPlusPlus &&
7041 !Kind.isImplicitValueInit()) {
7042 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
7044 TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type,
7045 Kind.getRange().getBegin());
7047 CurInit = new (S.Context) CXXScalarValueInitExpr(
7048 Entity.getType().getNonLValueExprType(S.Context), TSInfo,
7049 Kind.getRange().getEnd());
7051 CurInit = new (S.Context) ImplicitValueInitExpr(Step->Type);
7056 case SK_CAssignment: {
7057 QualType SourceType = CurInit.get()->getType();
7058 // Save off the initial CurInit in case we need to emit a diagnostic
7059 ExprResult InitialCurInit = CurInit;
7060 ExprResult Result = CurInit;
7061 Sema::AssignConvertType ConvTy =
7062 S.CheckSingleAssignmentConstraints(Step->Type, Result, true,
7063 Entity.getKind() == InitializedEntity::EK_Parameter_CF_Audited);
7064 if (Result.isInvalid())
7068 // If this is a call, allow conversion to a transparent union.
7069 ExprResult CurInitExprRes = CurInit;
7070 if (ConvTy != Sema::Compatible &&
7071 Entity.isParameterKind() &&
7072 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes)
7073 == Sema::Compatible)
7074 ConvTy = Sema::Compatible;
7075 if (CurInitExprRes.isInvalid())
7077 CurInit = CurInitExprRes;
7080 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(),
7081 Step->Type, SourceType,
7082 InitialCurInit.get(),
7083 getAssignmentAction(Entity, true),
7085 PrintInitLocationNote(S, Entity);
7087 } else if (Complained)
7088 PrintInitLocationNote(S, Entity);
7092 case SK_StringInit: {
7093 QualType Ty = Step->Type;
7094 CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty,
7095 S.Context.getAsArrayType(Ty), S);
7099 case SK_ObjCObjectConversion:
7100 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
7101 CK_ObjCObjectLValueCast,
7102 CurInit.get()->getValueKind());
7105 case SK_ArrayLoopIndex: {
7106 Expr *Cur = CurInit.get();
7107 Expr *BaseExpr = new (S.Context)
7108 OpaqueValueExpr(Cur->getExprLoc(), Cur->getType(),
7109 Cur->getValueKind(), Cur->getObjectKind(), Cur);
7111 new (S.Context) ArrayInitIndexExpr(S.Context.getSizeType());
7112 CurInit = S.CreateBuiltinArraySubscriptExpr(
7113 BaseExpr, Kind.getLocation(), IndexExpr, Kind.getLocation());
7114 ArrayLoopCommonExprs.push_back(BaseExpr);
7118 case SK_ArrayLoopInit: {
7119 assert(!ArrayLoopCommonExprs.empty() &&
7120 "mismatched SK_ArrayLoopIndex and SK_ArrayLoopInit");
7121 Expr *Common = ArrayLoopCommonExprs.pop_back_val();
7122 CurInit = new (S.Context) ArrayInitLoopExpr(Step->Type, Common,
7127 case SK_GNUArrayInit:
7128 // Okay: we checked everything before creating this step. Note that
7129 // this is a GNU extension.
7130 S.Diag(Kind.getLocation(), diag::ext_array_init_copy)
7131 << Step->Type << CurInit.get()->getType()
7132 << CurInit.get()->getSourceRange();
7135 // If the destination type is an incomplete array type, update the
7136 // type accordingly.
7138 if (const IncompleteArrayType *IncompleteDest
7139 = S.Context.getAsIncompleteArrayType(Step->Type)) {
7140 if (const ConstantArrayType *ConstantSource
7141 = S.Context.getAsConstantArrayType(CurInit.get()->getType())) {
7142 *ResultType = S.Context.getConstantArrayType(
7143 IncompleteDest->getElementType(),
7144 ConstantSource->getSize(),
7145 ArrayType::Normal, 0);
7151 case SK_ParenthesizedArrayInit:
7152 // Okay: we checked everything before creating this step. Note that
7153 // this is a GNU extension.
7154 S.Diag(Kind.getLocation(), diag::ext_array_init_parens)
7155 << CurInit.get()->getSourceRange();
7158 case SK_PassByIndirectCopyRestore:
7159 case SK_PassByIndirectRestore:
7160 checkIndirectCopyRestoreSource(S, CurInit.get());
7161 CurInit = new (S.Context) ObjCIndirectCopyRestoreExpr(
7162 CurInit.get(), Step->Type,
7163 Step->Kind == SK_PassByIndirectCopyRestore);
7166 case SK_ProduceObjCObject:
7168 ImplicitCastExpr::Create(S.Context, Step->Type, CK_ARCProduceObject,
7169 CurInit.get(), nullptr, VK_RValue);
7172 case SK_StdInitializerList: {
7173 S.Diag(CurInit.get()->getExprLoc(),
7174 diag::warn_cxx98_compat_initializer_list_init)
7175 << CurInit.get()->getSourceRange();
7177 // Materialize the temporary into memory.
7178 MaterializeTemporaryExpr *MTE = S.CreateMaterializeTemporaryExpr(
7179 CurInit.get()->getType(), CurInit.get(),
7180 /*BoundToLvalueReference=*/false);
7182 // Maybe lifetime-extend the array temporary's subobjects to match the
7183 // entity's lifetime.
7184 if (const InitializedEntity *ExtendingEntity =
7185 getEntityForTemporaryLifetimeExtension(&Entity))
7186 if (performReferenceExtension(MTE, ExtendingEntity))
7187 warnOnLifetimeExtension(S, Entity, CurInit.get(),
7188 /*IsInitializerList=*/true,
7189 ExtendingEntity->getDecl());
7191 // Wrap it in a construction of a std::initializer_list<T>.
7192 CurInit = new (S.Context) CXXStdInitializerListExpr(Step->Type, MTE);
7194 // Bind the result, in case the library has given initializer_list a
7195 // non-trivial destructor.
7196 if (shouldBindAsTemporary(Entity))
7197 CurInit = S.MaybeBindToTemporary(CurInit.get());
7201 case SK_OCLSamplerInit: {
7202 // Sampler initialzation have 5 cases:
7203 // 1. function argument passing
7204 // 1a. argument is a file-scope variable
7205 // 1b. argument is a function-scope variable
7206 // 1c. argument is one of caller function's parameters
7207 // 2. variable initialization
7208 // 2a. initializing a file-scope variable
7209 // 2b. initializing a function-scope variable
7211 // For file-scope variables, since they cannot be initialized by function
7212 // call of __translate_sampler_initializer in LLVM IR, their references
7213 // need to be replaced by a cast from their literal initializers to
7214 // sampler type. Since sampler variables can only be used in function
7215 // calls as arguments, we only need to replace them when handling the
7216 // argument passing.
7217 assert(Step->Type->isSamplerT() &&
7218 "Sampler initialization on non-sampler type.");
7219 Expr *Init = CurInit.get();
7220 QualType SourceType = Init->getType();
7222 if (Entity.isParameterKind()) {
7223 if (!SourceType->isSamplerT() && !SourceType->isIntegerType()) {
7224 S.Diag(Kind.getLocation(), diag::err_sampler_argument_required)
7227 } else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Init)) {
7228 auto Var = cast<VarDecl>(DRE->getDecl());
7230 // No cast from integer to sampler is needed.
7231 if (!Var->hasGlobalStorage()) {
7232 CurInit = ImplicitCastExpr::Create(S.Context, Step->Type,
7233 CK_LValueToRValue, Init,
7234 /*BasePath=*/nullptr, VK_RValue);
7238 // For function call with a file-scope sampler variable as argument,
7239 // get the integer literal.
7240 // Do not diagnose if the file-scope variable does not have initializer
7241 // since this has already been diagnosed when parsing the variable
7243 if (!Var->getInit() || !isa<ImplicitCastExpr>(Var->getInit()))
7245 Init = cast<ImplicitCastExpr>(const_cast<Expr*>(
7246 Var->getInit()))->getSubExpr();
7247 SourceType = Init->getType();
7251 // Check initializer is 32 bit integer constant.
7252 // If the initializer is taken from global variable, do not diagnose since
7253 // this has already been done when parsing the variable declaration.
7254 if (!Init->isConstantInitializer(S.Context, false))
7257 if (!SourceType->isIntegerType() ||
7258 32 != S.Context.getIntWidth(SourceType)) {
7259 S.Diag(Kind.getLocation(), diag::err_sampler_initializer_not_integer)
7264 llvm::APSInt Result;
7265 Init->EvaluateAsInt(Result, S.Context);
7266 const uint64_t SamplerValue = Result.getLimitedValue();
7267 // 32-bit value of sampler's initializer is interpreted as
7268 // bit-field with the following structure:
7269 // |unspecified|Filter|Addressing Mode| Normalized Coords|
7270 // |31 6|5 4|3 1| 0|
7271 // This structure corresponds to enum values of sampler properties
7272 // defined in SPIR spec v1.2 and also opencl-c.h
7273 unsigned AddressingMode = (0x0E & SamplerValue) >> 1;
7274 unsigned FilterMode = (0x30 & SamplerValue) >> 4;
7275 if (FilterMode != 1 && FilterMode != 2)
7276 S.Diag(Kind.getLocation(),
7277 diag::warn_sampler_initializer_invalid_bits)
7279 if (AddressingMode > 4)
7280 S.Diag(Kind.getLocation(),
7281 diag::warn_sampler_initializer_invalid_bits)
7282 << "Addressing Mode";
7285 // Cases 1a, 2a and 2b
7286 // Insert cast from integer to sampler.
7287 CurInit = S.ImpCastExprToType(Init, S.Context.OCLSamplerTy,
7288 CK_IntToOCLSampler);
7291 case SK_OCLZeroEvent: {
7292 assert(Step->Type->isEventT() &&
7293 "Event initialization on non-event type.");
7295 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
7297 CurInit.get()->getValueKind());
7300 case SK_OCLZeroQueue: {
7301 assert(Step->Type->isQueueT() &&
7302 "Event initialization on non queue type.");
7304 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
7306 CurInit.get()->getValueKind());
7312 // Diagnose non-fatal problems with the completed initialization.
7313 if (Entity.getKind() == InitializedEntity::EK_Member &&
7314 cast<FieldDecl>(Entity.getDecl())->isBitField())
7315 S.CheckBitFieldInitialization(Kind.getLocation(),
7316 cast<FieldDecl>(Entity.getDecl()),
7319 // Check for std::move on construction.
7320 if (const Expr *E = CurInit.get()) {
7321 CheckMoveOnConstruction(S, E,
7322 Entity.getKind() == InitializedEntity::EK_Result);
7328 /// Somewhere within T there is an uninitialized reference subobject.
7329 /// Dig it out and diagnose it.
7330 static bool DiagnoseUninitializedReference(Sema &S, SourceLocation Loc,
7332 if (T->isReferenceType()) {
7333 S.Diag(Loc, diag::err_reference_without_init)
7334 << T.getNonReferenceType();
7338 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
7339 if (!RD || !RD->hasUninitializedReferenceMember())
7342 for (const auto *FI : RD->fields()) {
7343 if (FI->isUnnamedBitfield())
7346 if (DiagnoseUninitializedReference(S, FI->getLocation(), FI->getType())) {
7347 S.Diag(Loc, diag::note_value_initialization_here) << RD;
7352 for (const auto &BI : RD->bases()) {
7353 if (DiagnoseUninitializedReference(S, BI.getLocStart(), BI.getType())) {
7354 S.Diag(Loc, diag::note_value_initialization_here) << RD;
7363 //===----------------------------------------------------------------------===//
7364 // Diagnose initialization failures
7365 //===----------------------------------------------------------------------===//
7367 /// Emit notes associated with an initialization that failed due to a
7368 /// "simple" conversion failure.
7369 static void emitBadConversionNotes(Sema &S, const InitializedEntity &entity,
7371 QualType destType = entity.getType();
7372 if (destType.getNonReferenceType()->isObjCObjectPointerType() &&
7373 op->getType()->isObjCObjectPointerType()) {
7375 // Emit a possible note about the conversion failing because the
7376 // operand is a message send with a related result type.
7377 S.EmitRelatedResultTypeNote(op);
7379 // Emit a possible note about a return failing because we're
7380 // expecting a related result type.
7381 if (entity.getKind() == InitializedEntity::EK_Result)
7382 S.EmitRelatedResultTypeNoteForReturn(destType);
7386 static void diagnoseListInit(Sema &S, const InitializedEntity &Entity,
7387 InitListExpr *InitList) {
7388 QualType DestType = Entity.getType();
7391 if (S.getLangOpts().CPlusPlus11 && S.isStdInitializerList(DestType, &E)) {
7392 QualType ArrayType = S.Context.getConstantArrayType(
7394 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
7395 InitList->getNumInits()),
7396 clang::ArrayType::Normal, 0);
7397 InitializedEntity HiddenArray =
7398 InitializedEntity::InitializeTemporary(ArrayType);
7399 return diagnoseListInit(S, HiddenArray, InitList);
7402 if (DestType->isReferenceType()) {
7403 // A list-initialization failure for a reference means that we tried to
7404 // create a temporary of the inner type (per [dcl.init.list]p3.6) and the
7405 // inner initialization failed.
7406 QualType T = DestType->getAs<ReferenceType>()->getPointeeType();
7407 diagnoseListInit(S, InitializedEntity::InitializeTemporary(T), InitList);
7408 SourceLocation Loc = InitList->getLocStart();
7409 if (auto *D = Entity.getDecl())
7410 Loc = D->getLocation();
7411 S.Diag(Loc, diag::note_in_reference_temporary_list_initializer) << T;
7415 InitListChecker DiagnoseInitList(S, Entity, InitList, DestType,
7416 /*VerifyOnly=*/false,
7417 /*TreatUnavailableAsInvalid=*/false);
7418 assert(DiagnoseInitList.HadError() &&
7419 "Inconsistent init list check result.");
7422 bool InitializationSequence::Diagnose(Sema &S,
7423 const InitializedEntity &Entity,
7424 const InitializationKind &Kind,
7425 ArrayRef<Expr *> Args) {
7429 QualType DestType = Entity.getType();
7431 case FK_TooManyInitsForReference:
7432 // FIXME: Customize for the initialized entity?
7434 // Dig out the reference subobject which is uninitialized and diagnose it.
7435 // If this is value-initialization, this could be nested some way within
7437 assert(Kind.getKind() == InitializationKind::IK_Value ||
7438 DestType->isReferenceType());
7440 DiagnoseUninitializedReference(S, Kind.getLocation(), DestType);
7441 assert(Diagnosed && "couldn't find uninitialized reference to diagnose");
7443 } else // FIXME: diagnostic below could be better!
7444 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits)
7445 << SourceRange(Args.front()->getLocStart(), Args.back()->getLocEnd());
7447 case FK_ParenthesizedListInitForReference:
7448 S.Diag(Kind.getLocation(), diag::err_list_init_in_parens)
7449 << 1 << Entity.getType() << Args[0]->getSourceRange();
7452 case FK_ArrayNeedsInitList:
7453 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 0;
7455 case FK_ArrayNeedsInitListOrStringLiteral:
7456 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 1;
7458 case FK_ArrayNeedsInitListOrWideStringLiteral:
7459 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 2;
7461 case FK_NarrowStringIntoWideCharArray:
7462 S.Diag(Kind.getLocation(), diag::err_array_init_narrow_string_into_wchar);
7464 case FK_WideStringIntoCharArray:
7465 S.Diag(Kind.getLocation(), diag::err_array_init_wide_string_into_char);
7467 case FK_IncompatWideStringIntoWideChar:
7468 S.Diag(Kind.getLocation(),
7469 diag::err_array_init_incompat_wide_string_into_wchar);
7471 case FK_ArrayTypeMismatch:
7472 case FK_NonConstantArrayInit:
7473 S.Diag(Kind.getLocation(),
7474 (Failure == FK_ArrayTypeMismatch
7475 ? diag::err_array_init_different_type
7476 : diag::err_array_init_non_constant_array))
7477 << DestType.getNonReferenceType()
7478 << Args[0]->getType()
7479 << Args[0]->getSourceRange();
7482 case FK_VariableLengthArrayHasInitializer:
7483 S.Diag(Kind.getLocation(), diag::err_variable_object_no_init)
7484 << Args[0]->getSourceRange();
7487 case FK_AddressOfOverloadFailed: {
7488 DeclAccessPair Found;
7489 S.ResolveAddressOfOverloadedFunction(Args[0],
7490 DestType.getNonReferenceType(),
7496 case FK_AddressOfUnaddressableFunction: {
7497 auto *FD = cast<FunctionDecl>(cast<DeclRefExpr>(Args[0])->getDecl());
7498 S.checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
7499 Args[0]->getLocStart());
7503 case FK_ReferenceInitOverloadFailed:
7504 case FK_UserConversionOverloadFailed:
7505 switch (FailedOverloadResult) {
7507 if (Failure == FK_UserConversionOverloadFailed)
7508 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition)
7509 << Args[0]->getType() << DestType
7510 << Args[0]->getSourceRange();
7512 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous)
7513 << DestType << Args[0]->getType()
7514 << Args[0]->getSourceRange();
7516 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args);
7519 case OR_No_Viable_Function:
7520 if (!S.RequireCompleteType(Kind.getLocation(),
7521 DestType.getNonReferenceType(),
7522 diag::err_typecheck_nonviable_condition_incomplete,
7523 Args[0]->getType(), Args[0]->getSourceRange()))
7524 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition)
7525 << (Entity.getKind() == InitializedEntity::EK_Result)
7526 << Args[0]->getType() << Args[0]->getSourceRange()
7527 << DestType.getNonReferenceType();
7529 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args);
7533 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function)
7534 << Args[0]->getType() << DestType.getNonReferenceType()
7535 << Args[0]->getSourceRange();
7536 OverloadCandidateSet::iterator Best;
7537 OverloadingResult Ovl
7538 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best,
7540 if (Ovl == OR_Deleted) {
7541 S.NoteDeletedFunction(Best->Function);
7543 llvm_unreachable("Inconsistent overload resolution?");
7549 llvm_unreachable("Conversion did not fail!");
7553 case FK_NonConstLValueReferenceBindingToTemporary:
7554 if (isa<InitListExpr>(Args[0])) {
7555 S.Diag(Kind.getLocation(),
7556 diag::err_lvalue_reference_bind_to_initlist)
7557 << DestType.getNonReferenceType().isVolatileQualified()
7558 << DestType.getNonReferenceType()
7559 << Args[0]->getSourceRange();
7562 // Intentional fallthrough
7564 case FK_NonConstLValueReferenceBindingToUnrelated:
7565 S.Diag(Kind.getLocation(),
7566 Failure == FK_NonConstLValueReferenceBindingToTemporary
7567 ? diag::err_lvalue_reference_bind_to_temporary
7568 : diag::err_lvalue_reference_bind_to_unrelated)
7569 << DestType.getNonReferenceType().isVolatileQualified()
7570 << DestType.getNonReferenceType()
7571 << Args[0]->getType()
7572 << Args[0]->getSourceRange();
7575 case FK_NonConstLValueReferenceBindingToBitfield: {
7576 // We don't necessarily have an unambiguous source bit-field.
7577 FieldDecl *BitField = Args[0]->getSourceBitField();
7578 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield)
7579 << DestType.isVolatileQualified()
7580 << (BitField ? BitField->getDeclName() : DeclarationName())
7581 << (BitField != nullptr)
7582 << Args[0]->getSourceRange();
7584 S.Diag(BitField->getLocation(), diag::note_bitfield_decl);
7588 case FK_NonConstLValueReferenceBindingToVectorElement:
7589 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element)
7590 << DestType.isVolatileQualified()
7591 << Args[0]->getSourceRange();
7594 case FK_RValueReferenceBindingToLValue:
7595 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref)
7596 << DestType.getNonReferenceType() << Args[0]->getType()
7597 << Args[0]->getSourceRange();
7600 case FK_ReferenceInitDropsQualifiers: {
7601 QualType SourceType = Args[0]->getType();
7602 QualType NonRefType = DestType.getNonReferenceType();
7603 Qualifiers DroppedQualifiers =
7604 SourceType.getQualifiers() - NonRefType.getQualifiers();
7606 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals)
7609 << DroppedQualifiers.getCVRQualifiers()
7610 << Args[0]->getSourceRange();
7614 case FK_ReferenceInitFailed:
7615 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed)
7616 << DestType.getNonReferenceType()
7617 << Args[0]->isLValue()
7618 << Args[0]->getType()
7619 << Args[0]->getSourceRange();
7620 emitBadConversionNotes(S, Entity, Args[0]);
7623 case FK_ConversionFailed: {
7624 QualType FromType = Args[0]->getType();
7625 PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed)
7626 << (int)Entity.getKind()
7628 << Args[0]->isLValue()
7630 << Args[0]->getSourceRange();
7631 S.HandleFunctionTypeMismatch(PDiag, FromType, DestType);
7632 S.Diag(Kind.getLocation(), PDiag);
7633 emitBadConversionNotes(S, Entity, Args[0]);
7637 case FK_ConversionFromPropertyFailed:
7638 // No-op. This error has already been reported.
7641 case FK_TooManyInitsForScalar: {
7644 auto *InitList = dyn_cast<InitListExpr>(Args[0]);
7645 if (InitList && InitList->getNumInits() >= 1) {
7646 R = SourceRange(InitList->getInit(0)->getLocEnd(), InitList->getLocEnd());
7648 assert(Args.size() > 1 && "Expected multiple initializers!");
7649 R = SourceRange(Args.front()->getLocEnd(), Args.back()->getLocEnd());
7652 R.setBegin(S.getLocForEndOfToken(R.getBegin()));
7653 if (Kind.isCStyleOrFunctionalCast())
7654 S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg)
7657 S.Diag(Kind.getLocation(), diag::err_excess_initializers)
7658 << /*scalar=*/2 << R;
7662 case FK_ParenthesizedListInitForScalar:
7663 S.Diag(Kind.getLocation(), diag::err_list_init_in_parens)
7664 << 0 << Entity.getType() << Args[0]->getSourceRange();
7667 case FK_ReferenceBindingToInitList:
7668 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list)
7669 << DestType.getNonReferenceType() << Args[0]->getSourceRange();
7672 case FK_InitListBadDestinationType:
7673 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type)
7674 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange();
7677 case FK_ListConstructorOverloadFailed:
7678 case FK_ConstructorOverloadFailed: {
7679 SourceRange ArgsRange;
7681 ArgsRange = SourceRange(Args.front()->getLocStart(),
7682 Args.back()->getLocEnd());
7684 if (Failure == FK_ListConstructorOverloadFailed) {
7685 assert(Args.size() == 1 &&
7686 "List construction from other than 1 argument.");
7687 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
7688 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
7691 // FIXME: Using "DestType" for the entity we're printing is probably
7693 switch (FailedOverloadResult) {
7695 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init)
7696 << DestType << ArgsRange;
7697 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args);
7700 case OR_No_Viable_Function:
7701 if (Kind.getKind() == InitializationKind::IK_Default &&
7702 (Entity.getKind() == InitializedEntity::EK_Base ||
7703 Entity.getKind() == InitializedEntity::EK_Member) &&
7704 isa<CXXConstructorDecl>(S.CurContext)) {
7705 // This is implicit default initialization of a member or
7706 // base within a constructor. If no viable function was
7707 // found, notify the user that they need to explicitly
7708 // initialize this base/member.
7709 CXXConstructorDecl *Constructor
7710 = cast<CXXConstructorDecl>(S.CurContext);
7711 const CXXRecordDecl *InheritedFrom = nullptr;
7712 if (auto Inherited = Constructor->getInheritedConstructor())
7713 InheritedFrom = Inherited.getShadowDecl()->getNominatedBaseClass();
7714 if (Entity.getKind() == InitializedEntity::EK_Base) {
7715 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
7716 << (InheritedFrom ? 2 : Constructor->isImplicit() ? 1 : 0)
7717 << S.Context.getTypeDeclType(Constructor->getParent())
7722 RecordDecl *BaseDecl
7723 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>()
7725 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl)
7726 << S.Context.getTagDeclType(BaseDecl);
7728 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
7729 << (InheritedFrom ? 2 : Constructor->isImplicit() ? 1 : 0)
7730 << S.Context.getTypeDeclType(Constructor->getParent())
7734 S.Diag(Entity.getDecl()->getLocation(),
7735 diag::note_member_declared_at);
7737 if (const RecordType *Record
7738 = Entity.getType()->getAs<RecordType>())
7739 S.Diag(Record->getDecl()->getLocation(),
7740 diag::note_previous_decl)
7741 << S.Context.getTagDeclType(Record->getDecl());
7746 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init)
7747 << DestType << ArgsRange;
7748 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args);
7752 OverloadCandidateSet::iterator Best;
7753 OverloadingResult Ovl
7754 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
7755 if (Ovl != OR_Deleted) {
7756 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
7757 << true << DestType << ArgsRange;
7758 llvm_unreachable("Inconsistent overload resolution?");
7762 // If this is a defaulted or implicitly-declared function, then
7763 // it was implicitly deleted. Make it clear that the deletion was
7765 if (S.isImplicitlyDeleted(Best->Function))
7766 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init)
7767 << S.getSpecialMember(cast<CXXMethodDecl>(Best->Function))
7768 << DestType << ArgsRange;
7770 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
7771 << true << DestType << ArgsRange;
7773 S.NoteDeletedFunction(Best->Function);
7778 llvm_unreachable("Conversion did not fail!");
7783 case FK_DefaultInitOfConst:
7784 if (Entity.getKind() == InitializedEntity::EK_Member &&
7785 isa<CXXConstructorDecl>(S.CurContext)) {
7786 // This is implicit default-initialization of a const member in
7787 // a constructor. Complain that it needs to be explicitly
7789 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext);
7790 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor)
7791 << (Constructor->getInheritedConstructor() ? 2 :
7792 Constructor->isImplicit() ? 1 : 0)
7793 << S.Context.getTypeDeclType(Constructor->getParent())
7795 << Entity.getName();
7796 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl)
7797 << Entity.getName();
7799 S.Diag(Kind.getLocation(), diag::err_default_init_const)
7800 << DestType << (bool)DestType->getAs<RecordType>();
7805 S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType,
7806 diag::err_init_incomplete_type);
7809 case FK_ListInitializationFailed: {
7810 // Run the init list checker again to emit diagnostics.
7811 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
7812 diagnoseListInit(S, Entity, InitList);
7816 case FK_PlaceholderType: {
7817 // FIXME: Already diagnosed!
7821 case FK_ExplicitConstructor: {
7822 S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor)
7823 << Args[0]->getSourceRange();
7824 OverloadCandidateSet::iterator Best;
7825 OverloadingResult Ovl
7826 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
7828 assert(Ovl == OR_Success && "Inconsistent overload resolution");
7829 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
7830 S.Diag(CtorDecl->getLocation(),
7831 diag::note_explicit_ctor_deduction_guide_here) << false;
7836 PrintInitLocationNote(S, Entity);
7840 void InitializationSequence::dump(raw_ostream &OS) const {
7841 switch (SequenceKind) {
7842 case FailedSequence: {
7843 OS << "Failed sequence: ";
7845 case FK_TooManyInitsForReference:
7846 OS << "too many initializers for reference";
7849 case FK_ParenthesizedListInitForReference:
7850 OS << "parenthesized list init for reference";
7853 case FK_ArrayNeedsInitList:
7854 OS << "array requires initializer list";
7857 case FK_AddressOfUnaddressableFunction:
7858 OS << "address of unaddressable function was taken";
7861 case FK_ArrayNeedsInitListOrStringLiteral:
7862 OS << "array requires initializer list or string literal";
7865 case FK_ArrayNeedsInitListOrWideStringLiteral:
7866 OS << "array requires initializer list or wide string literal";
7869 case FK_NarrowStringIntoWideCharArray:
7870 OS << "narrow string into wide char array";
7873 case FK_WideStringIntoCharArray:
7874 OS << "wide string into char array";
7877 case FK_IncompatWideStringIntoWideChar:
7878 OS << "incompatible wide string into wide char array";
7881 case FK_ArrayTypeMismatch:
7882 OS << "array type mismatch";
7885 case FK_NonConstantArrayInit:
7886 OS << "non-constant array initializer";
7889 case FK_AddressOfOverloadFailed:
7890 OS << "address of overloaded function failed";
7893 case FK_ReferenceInitOverloadFailed:
7894 OS << "overload resolution for reference initialization failed";
7897 case FK_NonConstLValueReferenceBindingToTemporary:
7898 OS << "non-const lvalue reference bound to temporary";
7901 case FK_NonConstLValueReferenceBindingToBitfield:
7902 OS << "non-const lvalue reference bound to bit-field";
7905 case FK_NonConstLValueReferenceBindingToVectorElement:
7906 OS << "non-const lvalue reference bound to vector element";
7909 case FK_NonConstLValueReferenceBindingToUnrelated:
7910 OS << "non-const lvalue reference bound to unrelated type";
7913 case FK_RValueReferenceBindingToLValue:
7914 OS << "rvalue reference bound to an lvalue";
7917 case FK_ReferenceInitDropsQualifiers:
7918 OS << "reference initialization drops qualifiers";
7921 case FK_ReferenceInitFailed:
7922 OS << "reference initialization failed";
7925 case FK_ConversionFailed:
7926 OS << "conversion failed";
7929 case FK_ConversionFromPropertyFailed:
7930 OS << "conversion from property failed";
7933 case FK_TooManyInitsForScalar:
7934 OS << "too many initializers for scalar";
7937 case FK_ParenthesizedListInitForScalar:
7938 OS << "parenthesized list init for reference";
7941 case FK_ReferenceBindingToInitList:
7942 OS << "referencing binding to initializer list";
7945 case FK_InitListBadDestinationType:
7946 OS << "initializer list for non-aggregate, non-scalar type";
7949 case FK_UserConversionOverloadFailed:
7950 OS << "overloading failed for user-defined conversion";
7953 case FK_ConstructorOverloadFailed:
7954 OS << "constructor overloading failed";
7957 case FK_DefaultInitOfConst:
7958 OS << "default initialization of a const variable";
7962 OS << "initialization of incomplete type";
7965 case FK_ListInitializationFailed:
7966 OS << "list initialization checker failure";
7969 case FK_VariableLengthArrayHasInitializer:
7970 OS << "variable length array has an initializer";
7973 case FK_PlaceholderType:
7974 OS << "initializer expression isn't contextually valid";
7977 case FK_ListConstructorOverloadFailed:
7978 OS << "list constructor overloading failed";
7981 case FK_ExplicitConstructor:
7982 OS << "list copy initialization chose explicit constructor";
7989 case DependentSequence:
7990 OS << "Dependent sequence\n";
7993 case NormalSequence:
7994 OS << "Normal sequence: ";
7998 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) {
7999 if (S != step_begin()) {
8004 case SK_ResolveAddressOfOverloadedFunction:
8005 OS << "resolve address of overloaded function";
8008 case SK_CastDerivedToBaseRValue:
8009 OS << "derived-to-base (rvalue)";
8012 case SK_CastDerivedToBaseXValue:
8013 OS << "derived-to-base (xvalue)";
8016 case SK_CastDerivedToBaseLValue:
8017 OS << "derived-to-base (lvalue)";
8020 case SK_BindReference:
8021 OS << "bind reference to lvalue";
8024 case SK_BindReferenceToTemporary:
8025 OS << "bind reference to a temporary";
8029 OS << "final copy in class direct-initialization";
8032 case SK_ExtraneousCopyToTemporary:
8033 OS << "extraneous C++03 copy to temporary";
8036 case SK_UserConversion:
8037 OS << "user-defined conversion via " << *S->Function.Function;
8040 case SK_QualificationConversionRValue:
8041 OS << "qualification conversion (rvalue)";
8044 case SK_QualificationConversionXValue:
8045 OS << "qualification conversion (xvalue)";
8048 case SK_QualificationConversionLValue:
8049 OS << "qualification conversion (lvalue)";
8052 case SK_AtomicConversion:
8053 OS << "non-atomic-to-atomic conversion";
8056 case SK_LValueToRValue:
8057 OS << "load (lvalue to rvalue)";
8060 case SK_ConversionSequence:
8061 OS << "implicit conversion sequence (";
8062 S->ICS->dump(); // FIXME: use OS
8066 case SK_ConversionSequenceNoNarrowing:
8067 OS << "implicit conversion sequence with narrowing prohibited (";
8068 S->ICS->dump(); // FIXME: use OS
8072 case SK_ListInitialization:
8073 OS << "list aggregate initialization";
8076 case SK_UnwrapInitList:
8077 OS << "unwrap reference initializer list";
8080 case SK_RewrapInitList:
8081 OS << "rewrap reference initializer list";
8084 case SK_ConstructorInitialization:
8085 OS << "constructor initialization";
8088 case SK_ConstructorInitializationFromList:
8089 OS << "list initialization via constructor";
8092 case SK_ZeroInitialization:
8093 OS << "zero initialization";
8096 case SK_CAssignment:
8097 OS << "C assignment";
8101 OS << "string initialization";
8104 case SK_ObjCObjectConversion:
8105 OS << "Objective-C object conversion";
8108 case SK_ArrayLoopIndex:
8109 OS << "indexing for array initialization loop";
8112 case SK_ArrayLoopInit:
8113 OS << "array initialization loop";
8117 OS << "array initialization";
8120 case SK_GNUArrayInit:
8121 OS << "array initialization (GNU extension)";
8124 case SK_ParenthesizedArrayInit:
8125 OS << "parenthesized array initialization";
8128 case SK_PassByIndirectCopyRestore:
8129 OS << "pass by indirect copy and restore";
8132 case SK_PassByIndirectRestore:
8133 OS << "pass by indirect restore";
8136 case SK_ProduceObjCObject:
8137 OS << "Objective-C object retension";
8140 case SK_StdInitializerList:
8141 OS << "std::initializer_list from initializer list";
8144 case SK_StdInitializerListConstructorCall:
8145 OS << "list initialization from std::initializer_list";
8148 case SK_OCLSamplerInit:
8149 OS << "OpenCL sampler_t from integer constant";
8152 case SK_OCLZeroEvent:
8153 OS << "OpenCL event_t from zero";
8156 case SK_OCLZeroQueue:
8157 OS << "OpenCL queue_t from zero";
8161 OS << " [" << S->Type.getAsString() << ']';
8167 void InitializationSequence::dump() const {
8171 static void DiagnoseNarrowingInInitList(Sema &S,
8172 const ImplicitConversionSequence &ICS,
8173 QualType PreNarrowingType,
8174 QualType EntityType,
8175 const Expr *PostInit) {
8176 const StandardConversionSequence *SCS = nullptr;
8177 switch (ICS.getKind()) {
8178 case ImplicitConversionSequence::StandardConversion:
8179 SCS = &ICS.Standard;
8181 case ImplicitConversionSequence::UserDefinedConversion:
8182 SCS = &ICS.UserDefined.After;
8184 case ImplicitConversionSequence::AmbiguousConversion:
8185 case ImplicitConversionSequence::EllipsisConversion:
8186 case ImplicitConversionSequence::BadConversion:
8190 // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion.
8191 APValue ConstantValue;
8192 QualType ConstantType;
8193 switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue,
8195 case NK_Not_Narrowing:
8196 case NK_Dependent_Narrowing:
8197 // No narrowing occurred.
8200 case NK_Type_Narrowing:
8201 // This was a floating-to-integer conversion, which is always considered a
8202 // narrowing conversion even if the value is a constant and can be
8203 // represented exactly as an integer.
8204 S.Diag(PostInit->getLocStart(),
8205 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
8206 ? diag::warn_init_list_type_narrowing
8207 : diag::ext_init_list_type_narrowing)
8208 << PostInit->getSourceRange()
8209 << PreNarrowingType.getLocalUnqualifiedType()
8210 << EntityType.getLocalUnqualifiedType();
8213 case NK_Constant_Narrowing:
8214 // A constant value was narrowed.
8215 S.Diag(PostInit->getLocStart(),
8216 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
8217 ? diag::warn_init_list_constant_narrowing
8218 : diag::ext_init_list_constant_narrowing)
8219 << PostInit->getSourceRange()
8220 << ConstantValue.getAsString(S.getASTContext(), ConstantType)
8221 << EntityType.getLocalUnqualifiedType();
8224 case NK_Variable_Narrowing:
8225 // A variable's value may have been narrowed.
8226 S.Diag(PostInit->getLocStart(),
8227 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
8228 ? diag::warn_init_list_variable_narrowing
8229 : diag::ext_init_list_variable_narrowing)
8230 << PostInit->getSourceRange()
8231 << PreNarrowingType.getLocalUnqualifiedType()
8232 << EntityType.getLocalUnqualifiedType();
8236 SmallString<128> StaticCast;
8237 llvm::raw_svector_ostream OS(StaticCast);
8238 OS << "static_cast<";
8239 if (const TypedefType *TT = EntityType->getAs<TypedefType>()) {
8240 // It's important to use the typedef's name if there is one so that the
8241 // fixit doesn't break code using types like int64_t.
8243 // FIXME: This will break if the typedef requires qualification. But
8244 // getQualifiedNameAsString() includes non-machine-parsable components.
8245 OS << *TT->getDecl();
8246 } else if (const BuiltinType *BT = EntityType->getAs<BuiltinType>())
8247 OS << BT->getName(S.getLangOpts());
8249 // Oops, we didn't find the actual type of the variable. Don't emit a fixit
8250 // with a broken cast.
8254 S.Diag(PostInit->getLocStart(), diag::note_init_list_narrowing_silence)
8255 << PostInit->getSourceRange()
8256 << FixItHint::CreateInsertion(PostInit->getLocStart(), OS.str())
8257 << FixItHint::CreateInsertion(
8258 S.getLocForEndOfToken(PostInit->getLocEnd()), ")");
8261 //===----------------------------------------------------------------------===//
8262 // Initialization helper functions
8263 //===----------------------------------------------------------------------===//
8265 Sema::CanPerformCopyInitialization(const InitializedEntity &Entity,
8267 if (Init.isInvalid())
8270 Expr *InitE = Init.get();
8271 assert(InitE && "No initialization expression");
8273 InitializationKind Kind
8274 = InitializationKind::CreateCopy(InitE->getLocStart(), SourceLocation());
8275 InitializationSequence Seq(*this, Entity, Kind, InitE);
8276 return !Seq.Failed();
8280 Sema::PerformCopyInitialization(const InitializedEntity &Entity,
8281 SourceLocation EqualLoc,
8283 bool TopLevelOfInitList,
8284 bool AllowExplicit) {
8285 if (Init.isInvalid())
8288 Expr *InitE = Init.get();
8289 assert(InitE && "No initialization expression?");
8291 if (EqualLoc.isInvalid())
8292 EqualLoc = InitE->getLocStart();
8294 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(),
8297 InitializationSequence Seq(*this, Entity, Kind, InitE, TopLevelOfInitList);
8299 // Prevent infinite recursion when performing parameter copy-initialization.
8300 const bool ShouldTrackCopy =
8301 Entity.isParameterKind() && Seq.isConstructorInitialization();
8302 if (ShouldTrackCopy) {
8303 if (llvm::find(CurrentParameterCopyTypes, Entity.getType()) !=
8304 CurrentParameterCopyTypes.end()) {
8305 Seq.SetOverloadFailure(
8306 InitializationSequence::FK_ConstructorOverloadFailed,
8307 OR_No_Viable_Function);
8309 // Try to give a meaningful diagnostic note for the problematic
8311 const auto LastStep = Seq.step_end() - 1;
8312 assert(LastStep->Kind ==
8313 InitializationSequence::SK_ConstructorInitialization);
8314 const FunctionDecl *Function = LastStep->Function.Function;
8316 llvm::find_if(Seq.getFailedCandidateSet(),
8317 [Function](const OverloadCandidate &Candidate) -> bool {
8318 return Candidate.Viable &&
8319 Candidate.Function == Function &&
8320 Candidate.Conversions.size() > 0;
8322 if (Candidate != Seq.getFailedCandidateSet().end() &&
8323 Function->getNumParams() > 0) {
8324 Candidate->Viable = false;
8325 Candidate->FailureKind = ovl_fail_bad_conversion;
8326 Candidate->Conversions[0].setBad(BadConversionSequence::no_conversion,
8328 Function->getParamDecl(0)->getType());
8331 CurrentParameterCopyTypes.push_back(Entity.getType());
8334 ExprResult Result = Seq.Perform(*this, Entity, Kind, InitE);
8336 if (ShouldTrackCopy)
8337 CurrentParameterCopyTypes.pop_back();
8342 QualType Sema::DeduceTemplateSpecializationFromInitializer(
8343 TypeSourceInfo *TSInfo, const InitializedEntity &Entity,
8344 const InitializationKind &Kind, MultiExprArg Inits) {
8345 auto *DeducedTST = dyn_cast<DeducedTemplateSpecializationType>(
8346 TSInfo->getType()->getContainedDeducedType());
8347 assert(DeducedTST && "not a deduced template specialization type");
8349 // We can only perform deduction for class templates.
8350 auto TemplateName = DeducedTST->getTemplateName();
8352 dyn_cast_or_null<ClassTemplateDecl>(TemplateName.getAsTemplateDecl());
8354 Diag(Kind.getLocation(),
8355 diag::err_deduced_non_class_template_specialization_type)
8356 << (int)getTemplateNameKindForDiagnostics(TemplateName) << TemplateName;
8357 if (auto *TD = TemplateName.getAsTemplateDecl())
8358 Diag(TD->getLocation(), diag::note_template_decl_here);
8362 // Can't deduce from dependent arguments.
8363 if (Expr::hasAnyTypeDependentArguments(Inits))
8364 return Context.DependentTy;
8366 // FIXME: Perform "exact type" matching first, per CWG discussion?
8367 // Or implement this via an implied 'T(T) -> T' deduction guide?
8369 // FIXME: Do we need/want a std::initializer_list<T> special case?
8371 // Look up deduction guides, including those synthesized from constructors.
8373 // C++1z [over.match.class.deduct]p1:
8374 // A set of functions and function templates is formed comprising:
8375 // - For each constructor of the class template designated by the
8376 // template-name, a function template [...]
8377 // - For each deduction-guide, a function or function template [...]
8378 DeclarationNameInfo NameInfo(
8379 Context.DeclarationNames.getCXXDeductionGuideName(Template),
8380 TSInfo->getTypeLoc().getEndLoc());
8381 LookupResult Guides(*this, NameInfo, LookupOrdinaryName);
8382 LookupQualifiedName(Guides, Template->getDeclContext());
8384 // FIXME: Do not diagnose inaccessible deduction guides. The standard isn't
8385 // clear on this, but they're not found by name so access does not apply.
8386 Guides.suppressDiagnostics();
8388 // Figure out if this is list-initialization.
8389 InitListExpr *ListInit =
8390 (Inits.size() == 1 && Kind.getKind() != InitializationKind::IK_Direct)
8391 ? dyn_cast<InitListExpr>(Inits[0])
8394 // C++1z [over.match.class.deduct]p1:
8395 // Initialization and overload resolution are performed as described in
8396 // [dcl.init] and [over.match.ctor], [over.match.copy], or [over.match.list]
8397 // (as appropriate for the type of initialization performed) for an object
8398 // of a hypothetical class type, where the selected functions and function
8399 // templates are considered to be the constructors of that class type
8401 // Since we know we're initializing a class type of a type unrelated to that
8402 // of the initializer, this reduces to something fairly reasonable.
8403 OverloadCandidateSet Candidates(Kind.getLocation(),
8404 OverloadCandidateSet::CSK_Normal);
8405 OverloadCandidateSet::iterator Best;
8406 auto tryToResolveOverload =
8407 [&](bool OnlyListConstructors) -> OverloadingResult {
8409 for (auto I = Guides.begin(), E = Guides.end(); I != E; ++I) {
8410 NamedDecl *D = (*I)->getUnderlyingDecl();
8411 if (D->isInvalidDecl())
8414 auto *TD = dyn_cast<FunctionTemplateDecl>(D);
8415 auto *GD = dyn_cast_or_null<CXXDeductionGuideDecl>(
8416 TD ? TD->getTemplatedDecl() : dyn_cast<FunctionDecl>(D));
8420 // C++ [over.match.ctor]p1: (non-list copy-initialization from non-class)
8421 // For copy-initialization, the candidate functions are all the
8422 // converting constructors (12.3.1) of that class.
8423 // C++ [over.match.copy]p1: (non-list copy-initialization from class)
8424 // The converting constructors of T are candidate functions.
8425 if (Kind.isCopyInit() && !ListInit) {
8426 // Only consider converting constructors.
8427 if (GD->isExplicit())
8430 // When looking for a converting constructor, deduction guides that
8431 // could never be called with one argument are not interesting to
8433 if (GD->getMinRequiredArguments() > 1 ||
8434 (GD->getNumParams() == 0 && !GD->isVariadic()))
8438 // C++ [over.match.list]p1.1: (first phase list initialization)
8439 // Initially, the candidate functions are the initializer-list
8440 // constructors of the class T
8441 if (OnlyListConstructors && !isInitListConstructor(GD))
8444 // C++ [over.match.list]p1.2: (second phase list initialization)
8445 // the candidate functions are all the constructors of the class T
8446 // C++ [over.match.ctor]p1: (all other cases)
8447 // the candidate functions are all the constructors of the class of
8448 // the object being initialized
8450 // C++ [over.best.ics]p4:
8451 // When [...] the constructor [...] is a candidate by
8452 // - [over.match.copy] (in all cases)
8453 // FIXME: The "second phase of [over.match.list] case can also
8454 // theoretically happen here, but it's not clear whether we can
8455 // ever have a parameter of the right type.
8456 bool SuppressUserConversions = Kind.isCopyInit();
8459 AddTemplateOverloadCandidate(TD, I.getPair(), /*ExplicitArgs*/ nullptr,
8461 SuppressUserConversions);
8463 AddOverloadCandidate(GD, I.getPair(), Inits, Candidates,
8464 SuppressUserConversions);
8466 return Candidates.BestViableFunction(*this, Kind.getLocation(), Best);
8469 OverloadingResult Result = OR_No_Viable_Function;
8471 // C++11 [over.match.list]p1, per DR1467: for list-initialization, first
8472 // try initializer-list constructors.
8474 bool TryListConstructors = true;
8476 // Try list constructors unless the list is empty and the class has one or
8477 // more default constructors, in which case those constructors win.
8478 if (!ListInit->getNumInits()) {
8479 for (NamedDecl *D : Guides) {
8480 auto *FD = dyn_cast<FunctionDecl>(D->getUnderlyingDecl());
8481 if (FD && FD->getMinRequiredArguments() == 0) {
8482 TryListConstructors = false;
8488 if (TryListConstructors)
8489 Result = tryToResolveOverload(/*OnlyListConstructor*/true);
8490 // Then unwrap the initializer list and try again considering all
8492 Inits = MultiExprArg(ListInit->getInits(), ListInit->getNumInits());
8495 // If list-initialization fails, or if we're doing any other kind of
8496 // initialization, we (eventually) consider constructors.
8497 if (Result == OR_No_Viable_Function)
8498 Result = tryToResolveOverload(/*OnlyListConstructor*/false);
8502 Diag(Kind.getLocation(), diag::err_deduced_class_template_ctor_ambiguous)
8504 // FIXME: For list-initialization candidates, it'd usually be better to
8505 // list why they were not viable when given the initializer list itself as
8507 Candidates.NoteCandidates(*this, OCD_ViableCandidates, Inits);
8510 case OR_No_Viable_Function: {
8511 CXXRecordDecl *Primary =
8512 cast<ClassTemplateDecl>(Template)->getTemplatedDecl();
8514 isCompleteType(Kind.getLocation(), Context.getTypeDeclType(Primary));
8515 Diag(Kind.getLocation(),
8516 Complete ? diag::err_deduced_class_template_ctor_no_viable
8517 : diag::err_deduced_class_template_incomplete)
8518 << TemplateName << !Guides.empty();
8519 Candidates.NoteCandidates(*this, OCD_AllCandidates, Inits);
8524 Diag(Kind.getLocation(), diag::err_deduced_class_template_deleted)
8526 NoteDeletedFunction(Best->Function);
8531 // C++ [over.match.list]p1:
8532 // In copy-list-initialization, if an explicit constructor is chosen, the
8533 // initialization is ill-formed.
8534 if (Kind.isCopyInit() && ListInit &&
8535 cast<CXXDeductionGuideDecl>(Best->Function)->isExplicit()) {
8536 bool IsDeductionGuide = !Best->Function->isImplicit();
8537 Diag(Kind.getLocation(), diag::err_deduced_class_template_explicit)
8538 << TemplateName << IsDeductionGuide;
8539 Diag(Best->Function->getLocation(),
8540 diag::note_explicit_ctor_deduction_guide_here)
8541 << IsDeductionGuide;
8545 // Make sure we didn't select an unusable deduction guide, and mark it
8547 DiagnoseUseOfDecl(Best->Function, Kind.getLocation());
8548 MarkFunctionReferenced(Kind.getLocation(), Best->Function);
8552 // C++ [dcl.type.class.deduct]p1:
8553 // The placeholder is replaced by the return type of the function selected
8554 // by overload resolution for class template deduction.
8555 return SubstAutoType(TSInfo->getType(), Best->Function->getReturnType());