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 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
627 const RecordDecl *RDecl = RType->getDecl();
628 if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
629 FillInEmptyInitForField(0, ILE->getInitializedFieldInUnion(),
630 Entity, ILE, RequiresSecondPass, FillWithNoInit);
631 else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
632 cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
633 for (auto *Field : RDecl->fields()) {
634 if (Field->hasInClassInitializer()) {
635 FillInEmptyInitForField(0, Field, Entity, ILE, RequiresSecondPass,
641 // The fields beyond ILE->getNumInits() are default initialized, so in
642 // order to leave them uninitialized, the ILE is expanded and the extra
643 // fields are then filled with NoInitExpr.
644 unsigned NumElems = numStructUnionElements(ILE->getType());
645 if (RDecl->hasFlexibleArrayMember())
647 if (ILE->getNumInits() < NumElems)
648 ILE->resizeInits(SemaRef.Context, NumElems);
652 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RDecl)) {
653 for (auto &Base : CXXRD->bases()) {
657 FillInEmptyInitForBase(Init, Base, Entity, ILE, RequiresSecondPass,
663 for (auto *Field : RDecl->fields()) {
664 if (Field->isUnnamedBitfield())
670 FillInEmptyInitForField(Init, Field, Entity, ILE, RequiresSecondPass,
677 // Only look at the first initialization of a union.
678 if (RDecl->isUnion())
686 QualType ElementType;
688 InitializedEntity ElementEntity = Entity;
689 unsigned NumInits = ILE->getNumInits();
690 unsigned NumElements = NumInits;
691 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) {
692 ElementType = AType->getElementType();
693 if (const auto *CAType = dyn_cast<ConstantArrayType>(AType))
694 NumElements = CAType->getSize().getZExtValue();
695 // For an array new with an unknown bound, ask for one additional element
696 // in order to populate the array filler.
697 if (Entity.isVariableLengthArrayNew())
699 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
701 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) {
702 ElementType = VType->getElementType();
703 NumElements = VType->getNumElements();
704 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
707 ElementType = ILE->getType();
709 for (unsigned Init = 0; Init != NumElements; ++Init) {
713 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement ||
714 ElementEntity.getKind() == InitializedEntity::EK_VectorElement)
715 ElementEntity.setElementIndex(Init);
717 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : nullptr);
718 if (!InitExpr && Init < NumInits && ILE->hasArrayFiller())
719 ILE->setInit(Init, ILE->getArrayFiller());
720 else if (!InitExpr && !ILE->hasArrayFiller()) {
721 Expr *Filler = nullptr;
724 Filler = new (SemaRef.Context) NoInitExpr(ElementType);
726 ExprResult ElementInit = PerformEmptyInit(SemaRef, ILE->getLocEnd(),
729 TreatUnavailableAsInvalid);
730 if (ElementInit.isInvalid()) {
735 Filler = ElementInit.getAs<Expr>();
740 } else if (Init < NumInits) {
741 // For arrays, just set the expression used for value-initialization
742 // of the "holes" in the array.
743 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement)
744 ILE->setArrayFiller(Filler);
746 ILE->setInit(Init, Filler);
748 // For arrays, just set the expression used for value-initialization
749 // of the rest of elements and exit.
750 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) {
751 ILE->setArrayFiller(Filler);
755 if (!isa<ImplicitValueInitExpr>(Filler) && !isa<NoInitExpr>(Filler)) {
756 // Empty initialization requires a constructor call, so
757 // extend the initializer list to include the constructor
758 // call and make a note that we'll need to take another pass
759 // through the initializer list.
760 ILE->updateInit(SemaRef.Context, Init, Filler);
761 RequiresSecondPass = true;
764 } else if (InitListExpr *InnerILE
765 = dyn_cast_or_null<InitListExpr>(InitExpr))
766 FillInEmptyInitializations(ElementEntity, InnerILE, RequiresSecondPass,
768 else if (DesignatedInitUpdateExpr *InnerDIUE
769 = dyn_cast_or_null<DesignatedInitUpdateExpr>(InitExpr))
770 FillInEmptyInitializations(ElementEntity, InnerDIUE->getUpdater(),
771 RequiresSecondPass, /*FillWithNoInit =*/ true);
775 InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity,
776 InitListExpr *IL, QualType &T,
778 bool TreatUnavailableAsInvalid)
779 : SemaRef(S), VerifyOnly(VerifyOnly),
780 TreatUnavailableAsInvalid(TreatUnavailableAsInvalid) {
781 // FIXME: Check that IL isn't already the semantic form of some other
782 // InitListExpr. If it is, we'd create a broken AST.
786 FullyStructuredList =
787 getStructuredSubobjectInit(IL, 0, T, nullptr, 0, IL->getSourceRange());
788 CheckExplicitInitList(Entity, IL, T, FullyStructuredList,
789 /*TopLevelObject=*/true);
791 if (!hadError && !VerifyOnly) {
792 bool RequiresSecondPass = false;
793 FillInEmptyInitializations(Entity, FullyStructuredList, RequiresSecondPass);
794 if (RequiresSecondPass && !hadError)
795 FillInEmptyInitializations(Entity, FullyStructuredList,
800 int InitListChecker::numArrayElements(QualType DeclType) {
801 // FIXME: use a proper constant
802 int maxElements = 0x7FFFFFFF;
803 if (const ConstantArrayType *CAT =
804 SemaRef.Context.getAsConstantArrayType(DeclType)) {
805 maxElements = static_cast<int>(CAT->getSize().getZExtValue());
810 int InitListChecker::numStructUnionElements(QualType DeclType) {
811 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
812 int InitializableMembers = 0;
813 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(structDecl))
814 InitializableMembers += CXXRD->getNumBases();
815 for (const auto *Field : structDecl->fields())
816 if (!Field->isUnnamedBitfield())
817 ++InitializableMembers;
819 if (structDecl->isUnion())
820 return std::min(InitializableMembers, 1);
821 return InitializableMembers - structDecl->hasFlexibleArrayMember();
824 /// Check whether the range of the initializer \p ParentIList from element
825 /// \p Index onwards can be used to initialize an object of type \p T. Update
826 /// \p Index to indicate how many elements of the list were consumed.
828 /// This also fills in \p StructuredList, from element \p StructuredIndex
829 /// onwards, with the fully-braced, desugared form of the initialization.
830 void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity,
831 InitListExpr *ParentIList,
832 QualType T, unsigned &Index,
833 InitListExpr *StructuredList,
834 unsigned &StructuredIndex) {
837 if (T->isArrayType())
838 maxElements = numArrayElements(T);
839 else if (T->isRecordType())
840 maxElements = numStructUnionElements(T);
841 else if (T->isVectorType())
842 maxElements = T->getAs<VectorType>()->getNumElements();
844 llvm_unreachable("CheckImplicitInitList(): Illegal type");
846 if (maxElements == 0) {
848 SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(),
849 diag::err_implicit_empty_initializer);
855 // Build a structured initializer list corresponding to this subobject.
856 InitListExpr *StructuredSubobjectInitList
857 = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList,
859 SourceRange(ParentIList->getInit(Index)->getLocStart(),
860 ParentIList->getSourceRange().getEnd()));
861 unsigned StructuredSubobjectInitIndex = 0;
863 // Check the element types and build the structural subobject.
864 unsigned StartIndex = Index;
865 CheckListElementTypes(Entity, ParentIList, T,
866 /*SubobjectIsDesignatorContext=*/false, Index,
867 StructuredSubobjectInitList,
868 StructuredSubobjectInitIndex);
871 StructuredSubobjectInitList->setType(T);
873 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1);
874 // Update the structured sub-object initializer so that it's ending
875 // range corresponds with the end of the last initializer it used.
876 if (EndIndex < ParentIList->getNumInits() &&
877 ParentIList->getInit(EndIndex)) {
878 SourceLocation EndLoc
879 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd();
880 StructuredSubobjectInitList->setRBraceLoc(EndLoc);
883 // Complain about missing braces.
884 if (T->isArrayType() || T->isRecordType()) {
885 SemaRef.Diag(StructuredSubobjectInitList->getLocStart(),
886 diag::warn_missing_braces)
887 << StructuredSubobjectInitList->getSourceRange()
888 << FixItHint::CreateInsertion(
889 StructuredSubobjectInitList->getLocStart(), "{")
890 << FixItHint::CreateInsertion(
891 SemaRef.getLocForEndOfToken(
892 StructuredSubobjectInitList->getLocEnd()),
898 /// Warn that \p Entity was of scalar type and was initialized by a
899 /// single-element braced initializer list.
900 static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
901 SourceRange Braces) {
902 // Don't warn during template instantiation. If the initialization was
903 // non-dependent, we warned during the initial parse; otherwise, the
904 // type might not be scalar in some uses of the template.
905 if (!S.ActiveTemplateInstantiations.empty())
910 switch (Entity.getKind()) {
911 case InitializedEntity::EK_VectorElement:
912 case InitializedEntity::EK_ComplexElement:
913 case InitializedEntity::EK_ArrayElement:
914 case InitializedEntity::EK_Parameter:
915 case InitializedEntity::EK_Parameter_CF_Audited:
916 case InitializedEntity::EK_Result:
917 // Extra braces here are suspicious.
918 DiagID = diag::warn_braces_around_scalar_init;
921 case InitializedEntity::EK_Member:
922 // Warn on aggregate initialization but not on ctor init list or
923 // default member initializer.
924 if (Entity.getParent())
925 DiagID = diag::warn_braces_around_scalar_init;
928 case InitializedEntity::EK_Variable:
929 case InitializedEntity::EK_LambdaCapture:
930 // No warning, might be direct-list-initialization.
931 // FIXME: Should we warn for copy-list-initialization in these cases?
934 case InitializedEntity::EK_New:
935 case InitializedEntity::EK_Temporary:
936 case InitializedEntity::EK_CompoundLiteralInit:
937 // No warning, braces are part of the syntax of the underlying construct.
940 case InitializedEntity::EK_RelatedResult:
941 // No warning, we already warned when initializing the result.
944 case InitializedEntity::EK_Exception:
945 case InitializedEntity::EK_Base:
946 case InitializedEntity::EK_Delegating:
947 case InitializedEntity::EK_BlockElement:
948 case InitializedEntity::EK_Binding:
949 llvm_unreachable("unexpected braced scalar init");
953 S.Diag(Braces.getBegin(), DiagID)
955 << FixItHint::CreateRemoval(Braces.getBegin())
956 << FixItHint::CreateRemoval(Braces.getEnd());
960 /// Check whether the initializer \p IList (that was written with explicit
961 /// braces) can be used to initialize an object of type \p T.
963 /// This also fills in \p StructuredList with the fully-braced, desugared
964 /// form of the initialization.
965 void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity,
966 InitListExpr *IList, QualType &T,
967 InitListExpr *StructuredList,
968 bool TopLevelObject) {
970 SyntacticToSemantic[IList] = StructuredList;
971 StructuredList->setSyntacticForm(IList);
974 unsigned Index = 0, StructuredIndex = 0;
975 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true,
976 Index, StructuredList, StructuredIndex, TopLevelObject);
979 if (!ExprTy->isArrayType())
980 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context);
981 IList->setType(ExprTy);
982 StructuredList->setType(ExprTy);
987 if (Index < IList->getNumInits()) {
988 // We have leftover initializers
990 if (SemaRef.getLangOpts().CPlusPlus ||
991 (SemaRef.getLangOpts().OpenCL &&
992 IList->getType()->isVectorType())) {
998 if (StructuredIndex == 1 &&
999 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) ==
1001 unsigned DK = diag::ext_excess_initializers_in_char_array_initializer;
1002 if (SemaRef.getLangOpts().CPlusPlus) {
1003 DK = diag::err_excess_initializers_in_char_array_initializer;
1007 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK)
1008 << IList->getInit(Index)->getSourceRange();
1009 } else if (!T->isIncompleteType()) {
1010 // Don't complain for incomplete types, since we'll get an error
1012 QualType CurrentObjectType = StructuredList->getType();
1014 CurrentObjectType->isArrayType()? 0 :
1015 CurrentObjectType->isVectorType()? 1 :
1016 CurrentObjectType->isScalarType()? 2 :
1017 CurrentObjectType->isUnionType()? 3 :
1020 unsigned DK = diag::ext_excess_initializers;
1021 if (SemaRef.getLangOpts().CPlusPlus) {
1022 DK = diag::err_excess_initializers;
1025 if (SemaRef.getLangOpts().OpenCL && initKind == 1) {
1026 DK = diag::err_excess_initializers;
1030 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK)
1031 << initKind << IList->getInit(Index)->getSourceRange();
1035 if (!VerifyOnly && T->isScalarType() &&
1036 IList->getNumInits() == 1 && !isa<InitListExpr>(IList->getInit(0)))
1037 warnBracedScalarInit(SemaRef, Entity, IList->getSourceRange());
1040 void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity,
1041 InitListExpr *IList,
1043 bool SubobjectIsDesignatorContext,
1045 InitListExpr *StructuredList,
1046 unsigned &StructuredIndex,
1047 bool TopLevelObject) {
1048 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) {
1049 // Explicitly braced initializer for complex type can be real+imaginary
1051 CheckComplexType(Entity, IList, DeclType, Index,
1052 StructuredList, StructuredIndex);
1053 } else if (DeclType->isScalarType()) {
1054 CheckScalarType(Entity, IList, DeclType, Index,
1055 StructuredList, StructuredIndex);
1056 } else if (DeclType->isVectorType()) {
1057 CheckVectorType(Entity, IList, DeclType, Index,
1058 StructuredList, StructuredIndex);
1059 } else if (DeclType->isRecordType()) {
1060 assert(DeclType->isAggregateType() &&
1061 "non-aggregate records should be handed in CheckSubElementType");
1062 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1064 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
1065 CXXRecordDecl::base_class_iterator());
1066 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1067 Bases = CXXRD->bases();
1068 CheckStructUnionTypes(Entity, IList, DeclType, Bases, RD->field_begin(),
1069 SubobjectIsDesignatorContext, Index, StructuredList,
1070 StructuredIndex, TopLevelObject);
1071 } else if (DeclType->isArrayType()) {
1073 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()),
1075 CheckArrayType(Entity, IList, DeclType, Zero,
1076 SubobjectIsDesignatorContext, Index,
1077 StructuredList, StructuredIndex);
1078 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) {
1079 // This type is invalid, issue a diagnostic.
1082 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type)
1085 } else if (DeclType->isReferenceType()) {
1086 CheckReferenceType(Entity, IList, DeclType, Index,
1087 StructuredList, StructuredIndex);
1088 } else if (DeclType->isObjCObjectType()) {
1090 SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class)
1095 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type)
1101 void InitListChecker::CheckSubElementType(const InitializedEntity &Entity,
1102 InitListExpr *IList,
1105 InitListExpr *StructuredList,
1106 unsigned &StructuredIndex) {
1107 Expr *expr = IList->getInit(Index);
1109 if (ElemType->isReferenceType())
1110 return CheckReferenceType(Entity, IList, ElemType, Index,
1111 StructuredList, StructuredIndex);
1113 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) {
1114 if (SubInitList->getNumInits() == 1 &&
1115 IsStringInit(SubInitList->getInit(0), ElemType, SemaRef.Context) ==
1117 expr = SubInitList->getInit(0);
1118 } else if (!SemaRef.getLangOpts().CPlusPlus) {
1119 InitListExpr *InnerStructuredList
1120 = getStructuredSubobjectInit(IList, Index, ElemType,
1121 StructuredList, StructuredIndex,
1122 SubInitList->getSourceRange(), true);
1123 CheckExplicitInitList(Entity, SubInitList, ElemType,
1124 InnerStructuredList);
1126 if (!hadError && !VerifyOnly) {
1127 bool RequiresSecondPass = false;
1128 FillInEmptyInitializations(Entity, InnerStructuredList,
1129 RequiresSecondPass);
1130 if (RequiresSecondPass && !hadError)
1131 FillInEmptyInitializations(Entity, InnerStructuredList,
1132 RequiresSecondPass);
1138 // C++ initialization is handled later.
1139 } else if (isa<ImplicitValueInitExpr>(expr)) {
1140 // This happens during template instantiation when we see an InitListExpr
1141 // that we've already checked once.
1142 assert(SemaRef.Context.hasSameType(expr->getType(), ElemType) &&
1143 "found implicit initialization for the wrong type");
1145 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1150 if (SemaRef.getLangOpts().CPlusPlus) {
1151 // C++ [dcl.init.aggr]p2:
1152 // Each member is copy-initialized from the corresponding
1153 // initializer-clause.
1155 // FIXME: Better EqualLoc?
1156 InitializationKind Kind =
1157 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation());
1158 InitializationSequence Seq(SemaRef, Entity, Kind, expr,
1159 /*TopLevelOfInitList*/ true);
1161 // C++14 [dcl.init.aggr]p13:
1162 // If the assignment-expression can initialize a member, the member is
1163 // initialized. Otherwise [...] brace elision is assumed
1165 // Brace elision is never performed if the element is not an
1166 // assignment-expression.
1167 if (Seq || isa<InitListExpr>(expr)) {
1170 Seq.Perform(SemaRef, Entity, Kind, expr);
1171 if (Result.isInvalid())
1174 UpdateStructuredListElement(StructuredList, StructuredIndex,
1175 Result.getAs<Expr>());
1182 // Fall through for subaggregate initialization
1183 } else if (ElemType->isScalarType() || ElemType->isAtomicType()) {
1184 // FIXME: Need to handle atomic aggregate types with implicit init lists.
1185 return CheckScalarType(Entity, IList, ElemType, Index,
1186 StructuredList, StructuredIndex);
1187 } else if (const ArrayType *arrayType =
1188 SemaRef.Context.getAsArrayType(ElemType)) {
1189 // arrayType can be incomplete if we're initializing a flexible
1190 // array member. There's nothing we can do with the completed
1191 // type here, though.
1193 if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) {
1195 CheckStringInit(expr, ElemType, arrayType, SemaRef);
1196 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1202 // Fall through for subaggregate initialization.
1205 assert((ElemType->isRecordType() || ElemType->isVectorType() ||
1206 ElemType->isClkEventT()) && "Unexpected type");
1210 // The initializer for a structure or union object that has
1211 // automatic storage duration shall be either an initializer
1212 // list as described below, or a single expression that has
1213 // compatible structure or union type. In the latter case, the
1214 // initial value of the object, including unnamed members, is
1215 // that of the expression.
1216 ExprResult ExprRes = expr;
1217 if (SemaRef.CheckSingleAssignmentConstraints(
1218 ElemType, ExprRes, !VerifyOnly) != Sema::Incompatible) {
1219 if (ExprRes.isInvalid())
1222 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.get());
1223 if (ExprRes.isInvalid())
1226 UpdateStructuredListElement(StructuredList, StructuredIndex,
1227 ExprRes.getAs<Expr>());
1232 // Fall through for subaggregate initialization
1235 // C++ [dcl.init.aggr]p12:
1237 // [...] Otherwise, if the member is itself a non-empty
1238 // subaggregate, brace elision is assumed and the initializer is
1239 // considered for the initialization of the first member of
1240 // the subaggregate.
1241 // OpenCL vector initializer is handled elsewhere.
1242 if ((!SemaRef.getLangOpts().OpenCL && ElemType->isVectorType()) ||
1243 ElemType->isAggregateType()) {
1244 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList,
1249 // We cannot initialize this element, so let
1250 // PerformCopyInitialization produce the appropriate diagnostic.
1251 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), expr,
1252 /*TopLevelOfInitList=*/true);
1260 void InitListChecker::CheckComplexType(const InitializedEntity &Entity,
1261 InitListExpr *IList, QualType DeclType,
1263 InitListExpr *StructuredList,
1264 unsigned &StructuredIndex) {
1265 assert(Index == 0 && "Index in explicit init list must be zero");
1267 // As an extension, clang supports complex initializers, which initialize
1268 // a complex number component-wise. When an explicit initializer list for
1269 // a complex number contains two two initializers, this extension kicks in:
1270 // it exepcts the initializer list to contain two elements convertible to
1271 // the element type of the complex type. The first element initializes
1272 // the real part, and the second element intitializes the imaginary part.
1274 if (IList->getNumInits() != 2)
1275 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1278 // This is an extension in C. (The builtin _Complex type does not exist
1279 // in the C++ standard.)
1280 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly)
1281 SemaRef.Diag(IList->getLocStart(), diag::ext_complex_component_init)
1282 << IList->getSourceRange();
1284 // Initialize the complex number.
1285 QualType elementType = DeclType->getAs<ComplexType>()->getElementType();
1286 InitializedEntity ElementEntity =
1287 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1289 for (unsigned i = 0; i < 2; ++i) {
1290 ElementEntity.setElementIndex(Index);
1291 CheckSubElementType(ElementEntity, IList, elementType, Index,
1292 StructuredList, StructuredIndex);
1296 void InitListChecker::CheckScalarType(const InitializedEntity &Entity,
1297 InitListExpr *IList, QualType DeclType,
1299 InitListExpr *StructuredList,
1300 unsigned &StructuredIndex) {
1301 if (Index >= IList->getNumInits()) {
1303 SemaRef.Diag(IList->getLocStart(),
1304 SemaRef.getLangOpts().CPlusPlus11 ?
1305 diag::warn_cxx98_compat_empty_scalar_initializer :
1306 diag::err_empty_scalar_initializer)
1307 << IList->getSourceRange();
1308 hadError = !SemaRef.getLangOpts().CPlusPlus11;
1314 Expr *expr = IList->getInit(Index);
1315 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) {
1316 // FIXME: This is invalid, and accepting it causes overload resolution
1317 // to pick the wrong overload in some corner cases.
1319 SemaRef.Diag(SubIList->getLocStart(),
1320 diag::ext_many_braces_around_scalar_init)
1321 << SubIList->getSourceRange();
1323 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList,
1326 } else if (isa<DesignatedInitExpr>(expr)) {
1328 SemaRef.Diag(expr->getLocStart(),
1329 diag::err_designator_for_scalar_init)
1330 << DeclType << expr->getSourceRange();
1338 if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
1345 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), expr,
1346 /*TopLevelOfInitList=*/true);
1348 Expr *ResultExpr = nullptr;
1350 if (Result.isInvalid())
1351 hadError = true; // types weren't compatible.
1353 ResultExpr = Result.getAs<Expr>();
1355 if (ResultExpr != expr) {
1356 // The type was promoted, update initializer list.
1357 IList->setInit(Index, ResultExpr);
1363 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1367 void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
1368 InitListExpr *IList, QualType DeclType,
1370 InitListExpr *StructuredList,
1371 unsigned &StructuredIndex) {
1372 if (Index >= IList->getNumInits()) {
1373 // FIXME: It would be wonderful if we could point at the actual member. In
1374 // general, it would be useful to pass location information down the stack,
1375 // so that we know the location (or decl) of the "current object" being
1378 SemaRef.Diag(IList->getLocStart(),
1379 diag::err_init_reference_member_uninitialized)
1381 << IList->getSourceRange();
1388 Expr *expr = IList->getInit(Index);
1389 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) {
1391 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list)
1392 << DeclType << IList->getSourceRange();
1400 if (!SemaRef.CanPerformCopyInitialization(Entity,expr))
1407 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), expr,
1408 /*TopLevelOfInitList=*/true);
1410 if (Result.isInvalid())
1413 expr = Result.getAs<Expr>();
1414 IList->setInit(Index, expr);
1419 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1423 void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
1424 InitListExpr *IList, QualType DeclType,
1426 InitListExpr *StructuredList,
1427 unsigned &StructuredIndex) {
1428 const VectorType *VT = DeclType->getAs<VectorType>();
1429 unsigned maxElements = VT->getNumElements();
1430 unsigned numEltsInit = 0;
1431 QualType elementType = VT->getElementType();
1433 if (Index >= IList->getNumInits()) {
1434 // Make sure the element type can be value-initialized.
1436 CheckEmptyInitializable(
1437 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1438 IList->getLocEnd());
1442 if (!SemaRef.getLangOpts().OpenCL) {
1443 // If the initializing element is a vector, try to copy-initialize
1444 // instead of breaking it apart (which is doomed to failure anyway).
1445 Expr *Init = IList->getInit(Index);
1446 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) {
1448 if (!SemaRef.CanPerformCopyInitialization(Entity, Init))
1455 SemaRef.PerformCopyInitialization(Entity, Init->getLocStart(), Init,
1456 /*TopLevelOfInitList=*/true);
1458 Expr *ResultExpr = nullptr;
1459 if (Result.isInvalid())
1460 hadError = true; // types weren't compatible.
1462 ResultExpr = Result.getAs<Expr>();
1464 if (ResultExpr != Init) {
1465 // The type was promoted, update initializer list.
1466 IList->setInit(Index, ResultExpr);
1472 UpdateStructuredListElement(StructuredList, StructuredIndex,
1478 InitializedEntity ElementEntity =
1479 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1481 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
1482 // Don't attempt to go past the end of the init list
1483 if (Index >= IList->getNumInits()) {
1485 CheckEmptyInitializable(ElementEntity, IList->getLocEnd());
1489 ElementEntity.setElementIndex(Index);
1490 CheckSubElementType(ElementEntity, IList, elementType, Index,
1491 StructuredList, StructuredIndex);
1497 bool isBigEndian = SemaRef.Context.getTargetInfo().isBigEndian();
1498 const VectorType *T = Entity.getType()->getAs<VectorType>();
1499 if (isBigEndian && (T->getVectorKind() == VectorType::NeonVector ||
1500 T->getVectorKind() == VectorType::NeonPolyVector)) {
1501 // The ability to use vector initializer lists is a GNU vector extension
1502 // and is unrelated to the NEON intrinsics in arm_neon.h. On little
1503 // endian machines it works fine, however on big endian machines it
1504 // exhibits surprising behaviour:
1506 // uint32x2_t x = {42, 64};
1507 // return vget_lane_u32(x, 0); // Will return 64.
1509 // Because of this, explicitly call out that it is non-portable.
1511 SemaRef.Diag(IList->getLocStart(),
1512 diag::warn_neon_vector_initializer_non_portable);
1514 const char *typeCode;
1515 unsigned typeSize = SemaRef.Context.getTypeSize(elementType);
1517 if (elementType->isFloatingType())
1519 else if (elementType->isSignedIntegerType())
1521 else if (elementType->isUnsignedIntegerType())
1524 llvm_unreachable("Invalid element type!");
1526 SemaRef.Diag(IList->getLocStart(),
1527 SemaRef.Context.getTypeSize(VT) > 64 ?
1528 diag::note_neon_vector_initializer_non_portable_q :
1529 diag::note_neon_vector_initializer_non_portable)
1530 << typeCode << typeSize;
1536 InitializedEntity ElementEntity =
1537 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1539 // OpenCL initializers allows vectors to be constructed from vectors.
1540 for (unsigned i = 0; i < maxElements; ++i) {
1541 // Don't attempt to go past the end of the init list
1542 if (Index >= IList->getNumInits())
1545 ElementEntity.setElementIndex(Index);
1547 QualType IType = IList->getInit(Index)->getType();
1548 if (!IType->isVectorType()) {
1549 CheckSubElementType(ElementEntity, IList, elementType, Index,
1550 StructuredList, StructuredIndex);
1554 const VectorType *IVT = IType->getAs<VectorType>();
1555 unsigned numIElts = IVT->getNumElements();
1557 if (IType->isExtVectorType())
1558 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts);
1560 VecType = SemaRef.Context.getVectorType(elementType, numIElts,
1561 IVT->getVectorKind());
1562 CheckSubElementType(ElementEntity, IList, VecType, Index,
1563 StructuredList, StructuredIndex);
1564 numEltsInit += numIElts;
1568 // OpenCL requires all elements to be initialized.
1569 if (numEltsInit != maxElements) {
1571 SemaRef.Diag(IList->getLocStart(),
1572 diag::err_vector_incorrect_num_initializers)
1573 << (numEltsInit < maxElements) << maxElements << numEltsInit;
1578 void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
1579 InitListExpr *IList, QualType &DeclType,
1580 llvm::APSInt elementIndex,
1581 bool SubobjectIsDesignatorContext,
1583 InitListExpr *StructuredList,
1584 unsigned &StructuredIndex) {
1585 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
1587 // Check for the special-case of initializing an array with a string.
1588 if (Index < IList->getNumInits()) {
1589 if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
1591 // We place the string literal directly into the resulting
1592 // initializer list. This is the only place where the structure
1593 // of the structured initializer list doesn't match exactly,
1594 // because doing so would involve allocating one character
1595 // constant for each string.
1597 CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef);
1598 UpdateStructuredListElement(StructuredList, StructuredIndex,
1599 IList->getInit(Index));
1600 StructuredList->resizeInits(SemaRef.Context, StructuredIndex);
1606 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) {
1607 // Check for VLAs; in standard C it would be possible to check this
1608 // earlier, but I don't know where clang accepts VLAs (gcc accepts
1609 // them in all sorts of strange places).
1611 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(),
1612 diag::err_variable_object_no_init)
1613 << VAT->getSizeExpr()->getSourceRange();
1620 // We might know the maximum number of elements in advance.
1621 llvm::APSInt maxElements(elementIndex.getBitWidth(),
1622 elementIndex.isUnsigned());
1623 bool maxElementsKnown = false;
1624 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) {
1625 maxElements = CAT->getSize();
1626 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth());
1627 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1628 maxElementsKnown = true;
1631 QualType elementType = arrayType->getElementType();
1632 while (Index < IList->getNumInits()) {
1633 Expr *Init = IList->getInit(Index);
1634 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1635 // If we're not the subobject that matches up with the '{' for
1636 // the designator, we shouldn't be handling the
1637 // designator. Return immediately.
1638 if (!SubobjectIsDesignatorContext)
1641 // Handle this designated initializer. elementIndex will be
1642 // updated to be the next array element we'll initialize.
1643 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1644 DeclType, nullptr, &elementIndex, Index,
1645 StructuredList, StructuredIndex, true,
1651 if (elementIndex.getBitWidth() > maxElements.getBitWidth())
1652 maxElements = maxElements.extend(elementIndex.getBitWidth());
1653 else if (elementIndex.getBitWidth() < maxElements.getBitWidth())
1654 elementIndex = elementIndex.extend(maxElements.getBitWidth());
1655 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1657 // If the array is of incomplete type, keep track of the number of
1658 // elements in the initializer.
1659 if (!maxElementsKnown && elementIndex > maxElements)
1660 maxElements = elementIndex;
1665 // If we know the maximum number of elements, and we've already
1666 // hit it, stop consuming elements in the initializer list.
1667 if (maxElementsKnown && elementIndex == maxElements)
1670 InitializedEntity ElementEntity =
1671 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex,
1673 // Check this element.
1674 CheckSubElementType(ElementEntity, IList, elementType, Index,
1675 StructuredList, StructuredIndex);
1678 // If the array is of incomplete type, keep track of the number of
1679 // elements in the initializer.
1680 if (!maxElementsKnown && elementIndex > maxElements)
1681 maxElements = elementIndex;
1683 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) {
1684 // If this is an incomplete array type, the actual type needs to
1685 // be calculated here.
1686 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned());
1687 if (maxElements == Zero) {
1688 // Sizing an array implicitly to zero is not allowed by ISO C,
1689 // but is supported by GNU.
1690 SemaRef.Diag(IList->getLocStart(),
1691 diag::ext_typecheck_zero_array_size);
1694 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements,
1695 ArrayType::Normal, 0);
1697 if (!hadError && VerifyOnly) {
1698 // If there are any members of the array that get value-initialized, check
1699 // that is possible. That happens if we know the bound and don't have
1700 // enough elements, or if we're performing an array new with an unknown
1702 // FIXME: This needs to detect holes left by designated initializers too.
1703 if ((maxElementsKnown && elementIndex < maxElements) ||
1704 Entity.isVariableLengthArrayNew())
1705 CheckEmptyInitializable(InitializedEntity::InitializeElement(
1706 SemaRef.Context, 0, Entity),
1707 IList->getLocEnd());
1711 bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
1714 bool TopLevelObject) {
1715 // Handle GNU flexible array initializers.
1716 unsigned FlexArrayDiag;
1717 if (isa<InitListExpr>(InitExpr) &&
1718 cast<InitListExpr>(InitExpr)->getNumInits() == 0) {
1719 // Empty flexible array init always allowed as an extension
1720 FlexArrayDiag = diag::ext_flexible_array_init;
1721 } else if (SemaRef.getLangOpts().CPlusPlus) {
1722 // Disallow flexible array init in C++; it is not required for gcc
1723 // compatibility, and it needs work to IRGen correctly in general.
1724 FlexArrayDiag = diag::err_flexible_array_init;
1725 } else if (!TopLevelObject) {
1726 // Disallow flexible array init on non-top-level object
1727 FlexArrayDiag = diag::err_flexible_array_init;
1728 } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
1729 // Disallow flexible array init on anything which is not a variable.
1730 FlexArrayDiag = diag::err_flexible_array_init;
1731 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) {
1732 // Disallow flexible array init on local variables.
1733 FlexArrayDiag = diag::err_flexible_array_init;
1735 // Allow other cases.
1736 FlexArrayDiag = diag::ext_flexible_array_init;
1740 SemaRef.Diag(InitExpr->getLocStart(),
1742 << InitExpr->getLocStart();
1743 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
1747 return FlexArrayDiag != diag::ext_flexible_array_init;
1750 void InitListChecker::CheckStructUnionTypes(
1751 const InitializedEntity &Entity, InitListExpr *IList, QualType DeclType,
1752 CXXRecordDecl::base_class_range Bases, RecordDecl::field_iterator Field,
1753 bool SubobjectIsDesignatorContext, unsigned &Index,
1754 InitListExpr *StructuredList, unsigned &StructuredIndex,
1755 bool TopLevelObject) {
1756 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl();
1758 // If the record is invalid, some of it's members are invalid. To avoid
1759 // confusion, we forgo checking the intializer for the entire record.
1760 if (structDecl->isInvalidDecl()) {
1761 // Assume it was supposed to consume a single initializer.
1767 if (DeclType->isUnionType() && IList->getNumInits() == 0) {
1768 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1770 // If there's a default initializer, use it.
1771 if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
1774 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
1775 Field != FieldEnd; ++Field) {
1776 if (Field->hasInClassInitializer()) {
1777 StructuredList->setInitializedFieldInUnion(*Field);
1778 // FIXME: Actually build a CXXDefaultInitExpr?
1784 // Value-initialize the first member of the union that isn't an unnamed
1786 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
1787 Field != FieldEnd; ++Field) {
1788 if (!Field->isUnnamedBitfield()) {
1790 CheckEmptyInitializable(
1791 InitializedEntity::InitializeMember(*Field, &Entity),
1792 IList->getLocEnd());
1794 StructuredList->setInitializedFieldInUnion(*Field);
1801 bool InitializedSomething = false;
1803 // If we have any base classes, they are initialized prior to the fields.
1804 for (auto &Base : Bases) {
1805 Expr *Init = Index < IList->getNumInits() ? IList->getInit(Index) : nullptr;
1806 SourceLocation InitLoc = Init ? Init->getLocStart() : IList->getLocEnd();
1808 // Designated inits always initialize fields, so if we see one, all
1809 // remaining base classes have no explicit initializer.
1810 if (Init && isa<DesignatedInitExpr>(Init))
1813 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
1814 SemaRef.Context, &Base, false, &Entity);
1816 CheckSubElementType(BaseEntity, IList, Base.getType(), Index,
1817 StructuredList, StructuredIndex);
1818 InitializedSomething = true;
1819 } else if (VerifyOnly) {
1820 CheckEmptyInitializable(BaseEntity, InitLoc);
1824 // If structDecl is a forward declaration, this loop won't do
1825 // anything except look at designated initializers; That's okay,
1826 // because an error should get printed out elsewhere. It might be
1827 // worthwhile to skip over the rest of the initializer, though.
1828 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl();
1829 RecordDecl::field_iterator FieldEnd = RD->field_end();
1830 bool CheckForMissingFields = true;
1831 while (Index < IList->getNumInits()) {
1832 Expr *Init = IList->getInit(Index);
1834 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1835 // If we're not the subobject that matches up with the '{' for
1836 // the designator, we shouldn't be handling the
1837 // designator. Return immediately.
1838 if (!SubobjectIsDesignatorContext)
1841 // Handle this designated initializer. Field will be updated to
1842 // the next field that we'll be initializing.
1843 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1844 DeclType, &Field, nullptr, Index,
1845 StructuredList, StructuredIndex,
1846 true, TopLevelObject))
1849 InitializedSomething = true;
1851 // Disable check for missing fields when designators are used.
1852 // This matches gcc behaviour.
1853 CheckForMissingFields = false;
1857 if (Field == FieldEnd) {
1858 // We've run out of fields. We're done.
1862 // We've already initialized a member of a union. We're done.
1863 if (InitializedSomething && DeclType->isUnionType())
1866 // If we've hit the flexible array member at the end, we're done.
1867 if (Field->getType()->isIncompleteArrayType())
1870 if (Field->isUnnamedBitfield()) {
1871 // Don't initialize unnamed bitfields, e.g. "int : 20;"
1876 // Make sure we can use this declaration.
1879 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
1881 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field,
1882 IList->getInit(Index)->getLocStart());
1890 InitializedEntity MemberEntity =
1891 InitializedEntity::InitializeMember(*Field, &Entity);
1892 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
1893 StructuredList, StructuredIndex);
1894 InitializedSomething = true;
1896 if (DeclType->isUnionType() && !VerifyOnly) {
1897 // Initialize the first field within the union.
1898 StructuredList->setInitializedFieldInUnion(*Field);
1904 // Emit warnings for missing struct field initializers.
1905 if (!VerifyOnly && InitializedSomething && CheckForMissingFields &&
1906 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() &&
1907 !DeclType->isUnionType()) {
1908 // It is possible we have one or more unnamed bitfields remaining.
1909 // Find first (if any) named field and emit warning.
1910 for (RecordDecl::field_iterator it = Field, end = RD->field_end();
1912 if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
1913 SemaRef.Diag(IList->getSourceRange().getEnd(),
1914 diag::warn_missing_field_initializers) << *it;
1920 // Check that any remaining fields can be value-initialized.
1921 if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() &&
1922 !Field->getType()->isIncompleteArrayType()) {
1923 // FIXME: Should check for holes left by designated initializers too.
1924 for (; Field != FieldEnd && !hadError; ++Field) {
1925 if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
1926 CheckEmptyInitializable(
1927 InitializedEntity::InitializeMember(*Field, &Entity),
1928 IList->getLocEnd());
1932 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() ||
1933 Index >= IList->getNumInits())
1936 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field,
1943 InitializedEntity MemberEntity =
1944 InitializedEntity::InitializeMember(*Field, &Entity);
1946 if (isa<InitListExpr>(IList->getInit(Index)))
1947 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
1948 StructuredList, StructuredIndex);
1950 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index,
1951 StructuredList, StructuredIndex);
1954 /// \brief Expand a field designator that refers to a member of an
1955 /// anonymous struct or union into a series of field designators that
1956 /// refers to the field within the appropriate subobject.
1958 static void ExpandAnonymousFieldDesignator(Sema &SemaRef,
1959 DesignatedInitExpr *DIE,
1961 IndirectFieldDecl *IndirectField) {
1962 typedef DesignatedInitExpr::Designator Designator;
1964 // Build the replacement designators.
1965 SmallVector<Designator, 4> Replacements;
1966 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(),
1967 PE = IndirectField->chain_end(); PI != PE; ++PI) {
1969 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
1970 DIE->getDesignator(DesigIdx)->getDotLoc(),
1971 DIE->getDesignator(DesigIdx)->getFieldLoc()));
1973 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
1974 SourceLocation(), SourceLocation()));
1975 assert(isa<FieldDecl>(*PI));
1976 Replacements.back().setField(cast<FieldDecl>(*PI));
1979 // Expand the current designator into the set of replacement
1980 // designators, so we have a full subobject path down to where the
1981 // member of the anonymous struct/union is actually stored.
1982 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0],
1983 &Replacements[0] + Replacements.size());
1986 static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef,
1987 DesignatedInitExpr *DIE) {
1988 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1;
1989 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs);
1990 for (unsigned I = 0; I < NumIndexExprs; ++I)
1991 IndexExprs[I] = DIE->getSubExpr(I + 1);
1992 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators(),
1994 DIE->getEqualOrColonLoc(),
1995 DIE->usesGNUSyntax(), DIE->getInit());
2000 // Callback to only accept typo corrections that are for field members of
2001 // the given struct or union.
2002 class FieldInitializerValidatorCCC : public CorrectionCandidateCallback {
2004 explicit FieldInitializerValidatorCCC(RecordDecl *RD)
2007 bool ValidateCandidate(const TypoCorrection &candidate) override {
2008 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>();
2009 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record);
2016 } // end anonymous namespace
2018 /// @brief Check the well-formedness of a C99 designated initializer.
2020 /// Determines whether the designated initializer @p DIE, which
2021 /// resides at the given @p Index within the initializer list @p
2022 /// IList, is well-formed for a current object of type @p DeclType
2023 /// (C99 6.7.8). The actual subobject that this designator refers to
2024 /// within the current subobject is returned in either
2025 /// @p NextField or @p NextElementIndex (whichever is appropriate).
2027 /// @param IList The initializer list in which this designated
2028 /// initializer occurs.
2030 /// @param DIE The designated initializer expression.
2032 /// @param DesigIdx The index of the current designator.
2034 /// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17),
2035 /// into which the designation in @p DIE should refer.
2037 /// @param NextField If non-NULL and the first designator in @p DIE is
2038 /// a field, this will be set to the field declaration corresponding
2039 /// to the field named by the designator.
2041 /// @param NextElementIndex If non-NULL and the first designator in @p
2042 /// DIE is an array designator or GNU array-range designator, this
2043 /// will be set to the last index initialized by this designator.
2045 /// @param Index Index into @p IList where the designated initializer
2048 /// @param StructuredList The initializer list expression that
2049 /// describes all of the subobject initializers in the order they'll
2050 /// actually be initialized.
2052 /// @returns true if there was an error, false otherwise.
2054 InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity,
2055 InitListExpr *IList,
2056 DesignatedInitExpr *DIE,
2058 QualType &CurrentObjectType,
2059 RecordDecl::field_iterator *NextField,
2060 llvm::APSInt *NextElementIndex,
2062 InitListExpr *StructuredList,
2063 unsigned &StructuredIndex,
2064 bool FinishSubobjectInit,
2065 bool TopLevelObject) {
2066 if (DesigIdx == DIE->size()) {
2067 // Check the actual initialization for the designated object type.
2068 bool prevHadError = hadError;
2070 // Temporarily remove the designator expression from the
2071 // initializer list that the child calls see, so that we don't try
2072 // to re-process the designator.
2073 unsigned OldIndex = Index;
2074 IList->setInit(OldIndex, DIE->getInit());
2076 CheckSubElementType(Entity, IList, CurrentObjectType, Index,
2077 StructuredList, StructuredIndex);
2079 // Restore the designated initializer expression in the syntactic
2080 // form of the initializer list.
2081 if (IList->getInit(OldIndex) != DIE->getInit())
2082 DIE->setInit(IList->getInit(OldIndex));
2083 IList->setInit(OldIndex, DIE);
2085 return hadError && !prevHadError;
2088 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx);
2089 bool IsFirstDesignator = (DesigIdx == 0);
2091 assert((IsFirstDesignator || StructuredList) &&
2092 "Need a non-designated initializer list to start from");
2094 // Determine the structural initializer list that corresponds to the
2095 // current subobject.
2096 if (IsFirstDesignator)
2097 StructuredList = SyntacticToSemantic.lookup(IList);
2099 Expr *ExistingInit = StructuredIndex < StructuredList->getNumInits() ?
2100 StructuredList->getInit(StructuredIndex) : nullptr;
2101 if (!ExistingInit && StructuredList->hasArrayFiller())
2102 ExistingInit = StructuredList->getArrayFiller();
2106 getStructuredSubobjectInit(IList, Index, CurrentObjectType,
2107 StructuredList, StructuredIndex,
2108 SourceRange(D->getLocStart(),
2110 else if (InitListExpr *Result = dyn_cast<InitListExpr>(ExistingInit))
2111 StructuredList = Result;
2113 if (DesignatedInitUpdateExpr *E =
2114 dyn_cast<DesignatedInitUpdateExpr>(ExistingInit))
2115 StructuredList = E->getUpdater();
2117 DesignatedInitUpdateExpr *DIUE =
2118 new (SemaRef.Context) DesignatedInitUpdateExpr(SemaRef.Context,
2119 D->getLocStart(), ExistingInit,
2121 StructuredList->updateInit(SemaRef.Context, StructuredIndex, DIUE);
2122 StructuredList = DIUE->getUpdater();
2125 // We need to check on source range validity because the previous
2126 // initializer does not have to be an explicit initializer. e.g.,
2128 // struct P { int a, b; };
2129 // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
2131 // There is an overwrite taking place because the first braced initializer
2132 // list "{ .a = 2 }" already provides value for .p.b (which is zero).
2133 if (ExistingInit->getSourceRange().isValid()) {
2134 // We are creating an initializer list that initializes the
2135 // subobjects of the current object, but there was already an
2136 // initialization that completely initialized the current
2137 // subobject, e.g., by a compound literal:
2139 // struct X { int a, b; };
2140 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2142 // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
2143 // designated initializer re-initializes the whole
2144 // subobject [0], overwriting previous initializers.
2145 SemaRef.Diag(D->getLocStart(),
2146 diag::warn_subobject_initializer_overrides)
2147 << SourceRange(D->getLocStart(), DIE->getLocEnd());
2149 SemaRef.Diag(ExistingInit->getLocStart(),
2150 diag::note_previous_initializer)
2151 << /*FIXME:has side effects=*/0
2152 << ExistingInit->getSourceRange();
2156 assert(StructuredList && "Expected a structured initializer list");
2159 if (D->isFieldDesignator()) {
2162 // If a designator has the form
2166 // then the current object (defined below) shall have
2167 // structure or union type and the identifier shall be the
2168 // name of a member of that type.
2169 const RecordType *RT = CurrentObjectType->getAs<RecordType>();
2171 SourceLocation Loc = D->getDotLoc();
2172 if (Loc.isInvalid())
2173 Loc = D->getFieldLoc();
2175 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr)
2176 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType;
2181 FieldDecl *KnownField = D->getField();
2183 IdentifierInfo *FieldName = D->getFieldName();
2184 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName);
2185 for (NamedDecl *ND : Lookup) {
2186 if (auto *FD = dyn_cast<FieldDecl>(ND)) {
2190 if (auto *IFD = dyn_cast<IndirectFieldDecl>(ND)) {
2191 // In verify mode, don't modify the original.
2193 DIE = CloneDesignatedInitExpr(SemaRef, DIE);
2194 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IFD);
2195 D = DIE->getDesignator(DesigIdx);
2196 KnownField = cast<FieldDecl>(*IFD->chain_begin());
2203 return true; // No typo correction when just trying this out.
2206 // Name lookup found something, but it wasn't a field.
2207 if (!Lookup.empty()) {
2208 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield)
2210 SemaRef.Diag(Lookup.front()->getLocation(),
2211 diag::note_field_designator_found);
2216 // Name lookup didn't find anything.
2217 // Determine whether this was a typo for another field name.
2218 if (TypoCorrection Corrected = SemaRef.CorrectTypo(
2219 DeclarationNameInfo(FieldName, D->getFieldLoc()),
2220 Sema::LookupMemberName, /*Scope=*/nullptr, /*SS=*/nullptr,
2221 llvm::make_unique<FieldInitializerValidatorCCC>(RT->getDecl()),
2222 Sema::CTK_ErrorRecovery, RT->getDecl())) {
2223 SemaRef.diagnoseTypo(
2225 SemaRef.PDiag(diag::err_field_designator_unknown_suggest)
2226 << FieldName << CurrentObjectType);
2227 KnownField = Corrected.getCorrectionDeclAs<FieldDecl>();
2230 // Typo correction didn't find anything.
2231 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown)
2232 << FieldName << CurrentObjectType;
2239 unsigned FieldIndex = 0;
2240 for (auto *FI : RT->getDecl()->fields()) {
2241 if (FI->isUnnamedBitfield())
2243 if (declaresSameEntity(KnownField, FI)) {
2250 RecordDecl::field_iterator Field =
2251 RecordDecl::field_iterator(DeclContext::decl_iterator(KnownField));
2253 // All of the fields of a union are located at the same place in
2254 // the initializer list.
2255 if (RT->getDecl()->isUnion()) {
2258 FieldDecl *CurrentField = StructuredList->getInitializedFieldInUnion();
2259 if (CurrentField && !declaresSameEntity(CurrentField, *Field)) {
2260 assert(StructuredList->getNumInits() == 1
2261 && "A union should never have more than one initializer!");
2263 // We're about to throw away an initializer, emit warning.
2264 SemaRef.Diag(D->getFieldLoc(),
2265 diag::warn_initializer_overrides)
2266 << D->getSourceRange();
2267 Expr *ExistingInit = StructuredList->getInit(0);
2268 SemaRef.Diag(ExistingInit->getLocStart(),
2269 diag::note_previous_initializer)
2270 << /*FIXME:has side effects=*/0
2271 << ExistingInit->getSourceRange();
2273 // remove existing initializer
2274 StructuredList->resizeInits(SemaRef.Context, 0);
2275 StructuredList->setInitializedFieldInUnion(nullptr);
2278 StructuredList->setInitializedFieldInUnion(*Field);
2282 // Make sure we can use this declaration.
2285 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
2287 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc());
2294 // Update the designator with the field declaration.
2295 D->setField(*Field);
2297 // Make sure that our non-designated initializer list has space
2298 // for a subobject corresponding to this field.
2299 if (FieldIndex >= StructuredList->getNumInits())
2300 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1);
2303 // This designator names a flexible array member.
2304 if (Field->getType()->isIncompleteArrayType()) {
2305 bool Invalid = false;
2306 if ((DesigIdx + 1) != DIE->size()) {
2307 // We can't designate an object within the flexible array
2308 // member (because GCC doesn't allow it).
2310 DesignatedInitExpr::Designator *NextD
2311 = DIE->getDesignator(DesigIdx + 1);
2312 SemaRef.Diag(NextD->getLocStart(),
2313 diag::err_designator_into_flexible_array_member)
2314 << SourceRange(NextD->getLocStart(),
2316 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2322 if (!hadError && !isa<InitListExpr>(DIE->getInit()) &&
2323 !isa<StringLiteral>(DIE->getInit())) {
2324 // The initializer is not an initializer list.
2326 SemaRef.Diag(DIE->getInit()->getLocStart(),
2327 diag::err_flexible_array_init_needs_braces)
2328 << DIE->getInit()->getSourceRange();
2329 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2335 // Check GNU flexible array initializer.
2336 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field,
2345 // Initialize the array.
2346 bool prevHadError = hadError;
2347 unsigned newStructuredIndex = FieldIndex;
2348 unsigned OldIndex = Index;
2349 IList->setInit(Index, DIE->getInit());
2351 InitializedEntity MemberEntity =
2352 InitializedEntity::InitializeMember(*Field, &Entity);
2353 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2354 StructuredList, newStructuredIndex);
2356 IList->setInit(OldIndex, DIE);
2357 if (hadError && !prevHadError) {
2362 StructuredIndex = FieldIndex;
2366 // Recurse to check later designated subobjects.
2367 QualType FieldType = Field->getType();
2368 unsigned newStructuredIndex = FieldIndex;
2370 InitializedEntity MemberEntity =
2371 InitializedEntity::InitializeMember(*Field, &Entity);
2372 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1,
2373 FieldType, nullptr, nullptr, Index,
2374 StructuredList, newStructuredIndex,
2375 FinishSubobjectInit, false))
2379 // Find the position of the next field to be initialized in this
2384 // If this the first designator, our caller will continue checking
2385 // the rest of this struct/class/union subobject.
2386 if (IsFirstDesignator) {
2389 StructuredIndex = FieldIndex;
2393 if (!FinishSubobjectInit)
2396 // We've already initialized something in the union; we're done.
2397 if (RT->getDecl()->isUnion())
2400 // Check the remaining fields within this class/struct/union subobject.
2401 bool prevHadError = hadError;
2404 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
2405 CXXRecordDecl::base_class_iterator());
2406 CheckStructUnionTypes(Entity, IList, CurrentObjectType, NoBases, Field,
2407 false, Index, StructuredList, FieldIndex);
2408 return hadError && !prevHadError;
2413 // If a designator has the form
2415 // [ constant-expression ]
2417 // then the current object (defined below) shall have array
2418 // type and the expression shall be an integer constant
2419 // expression. If the array is of unknown size, any
2420 // nonnegative value is valid.
2422 // Additionally, cope with the GNU extension that permits
2423 // designators of the form
2425 // [ constant-expression ... constant-expression ]
2426 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType);
2429 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array)
2430 << CurrentObjectType;
2435 Expr *IndexExpr = nullptr;
2436 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex;
2437 if (D->isArrayDesignator()) {
2438 IndexExpr = DIE->getArrayIndex(*D);
2439 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context);
2440 DesignatedEndIndex = DesignatedStartIndex;
2442 assert(D->isArrayRangeDesignator() && "Need array-range designator");
2444 DesignatedStartIndex =
2445 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context);
2446 DesignatedEndIndex =
2447 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context);
2448 IndexExpr = DIE->getArrayRangeEnd(*D);
2450 // Codegen can't handle evaluating array range designators that have side
2451 // effects, because we replicate the AST value for each initialized element.
2452 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple
2453 // elements with something that has a side effect, so codegen can emit an
2454 // "error unsupported" error instead of miscompiling the app.
2455 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&&
2456 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly)
2457 FullyStructuredList->sawArrayRangeDesignator();
2460 if (isa<ConstantArrayType>(AT)) {
2461 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false);
2462 DesignatedStartIndex
2463 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth());
2464 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned());
2466 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth());
2467 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned());
2468 if (DesignatedEndIndex >= MaxElements) {
2470 SemaRef.Diag(IndexExpr->getLocStart(),
2471 diag::err_array_designator_too_large)
2472 << DesignatedEndIndex.toString(10) << MaxElements.toString(10)
2473 << IndexExpr->getSourceRange();
2478 unsigned DesignatedIndexBitWidth =
2479 ConstantArrayType::getMaxSizeBits(SemaRef.Context);
2480 DesignatedStartIndex =
2481 DesignatedStartIndex.extOrTrunc(DesignatedIndexBitWidth);
2482 DesignatedEndIndex =
2483 DesignatedEndIndex.extOrTrunc(DesignatedIndexBitWidth);
2484 DesignatedStartIndex.setIsUnsigned(true);
2485 DesignatedEndIndex.setIsUnsigned(true);
2488 if (!VerifyOnly && StructuredList->isStringLiteralInit()) {
2489 // We're modifying a string literal init; we have to decompose the string
2490 // so we can modify the individual characters.
2491 ASTContext &Context = SemaRef.Context;
2492 Expr *SubExpr = StructuredList->getInit(0)->IgnoreParens();
2494 // Compute the character type
2495 QualType CharTy = AT->getElementType();
2497 // Compute the type of the integer literals.
2498 QualType PromotedCharTy = CharTy;
2499 if (CharTy->isPromotableIntegerType())
2500 PromotedCharTy = Context.getPromotedIntegerType(CharTy);
2501 unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy);
2503 if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) {
2504 // Get the length of the string.
2505 uint64_t StrLen = SL->getLength();
2506 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2507 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2508 StructuredList->resizeInits(Context, StrLen);
2510 // Build a literal for each character in the string, and put them into
2512 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2513 llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i));
2514 Expr *Init = new (Context) IntegerLiteral(
2515 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2516 if (CharTy != PromotedCharTy)
2517 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2518 Init, nullptr, VK_RValue);
2519 StructuredList->updateInit(Context, i, Init);
2522 ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr);
2524 Context.getObjCEncodingForType(E->getEncodedType(), Str);
2526 // Get the length of the string.
2527 uint64_t StrLen = Str.size();
2528 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2529 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2530 StructuredList->resizeInits(Context, StrLen);
2532 // Build a literal for each character in the string, and put them into
2534 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2535 llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]);
2536 Expr *Init = new (Context) IntegerLiteral(
2537 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2538 if (CharTy != PromotedCharTy)
2539 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2540 Init, nullptr, VK_RValue);
2541 StructuredList->updateInit(Context, i, Init);
2546 // Make sure that our non-designated initializer list has space
2547 // for a subobject corresponding to this array element.
2549 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits())
2550 StructuredList->resizeInits(SemaRef.Context,
2551 DesignatedEndIndex.getZExtValue() + 1);
2553 // Repeatedly perform subobject initializations in the range
2554 // [DesignatedStartIndex, DesignatedEndIndex].
2556 // Move to the next designator
2557 unsigned ElementIndex = DesignatedStartIndex.getZExtValue();
2558 unsigned OldIndex = Index;
2560 InitializedEntity ElementEntity =
2561 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
2563 while (DesignatedStartIndex <= DesignatedEndIndex) {
2564 // Recurse to check later designated subobjects.
2565 QualType ElementType = AT->getElementType();
2568 ElementEntity.setElementIndex(ElementIndex);
2569 if (CheckDesignatedInitializer(
2570 ElementEntity, IList, DIE, DesigIdx + 1, ElementType, nullptr,
2571 nullptr, Index, StructuredList, ElementIndex,
2572 FinishSubobjectInit && (DesignatedStartIndex == DesignatedEndIndex),
2576 // Move to the next index in the array that we'll be initializing.
2577 ++DesignatedStartIndex;
2578 ElementIndex = DesignatedStartIndex.getZExtValue();
2581 // If this the first designator, our caller will continue checking
2582 // the rest of this array subobject.
2583 if (IsFirstDesignator) {
2584 if (NextElementIndex)
2585 *NextElementIndex = DesignatedStartIndex;
2586 StructuredIndex = ElementIndex;
2590 if (!FinishSubobjectInit)
2593 // Check the remaining elements within this array subobject.
2594 bool prevHadError = hadError;
2595 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex,
2596 /*SubobjectIsDesignatorContext=*/false, Index,
2597 StructuredList, ElementIndex);
2598 return hadError && !prevHadError;
2601 // Get the structured initializer list for a subobject of type
2602 // @p CurrentObjectType.
2604 InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
2605 QualType CurrentObjectType,
2606 InitListExpr *StructuredList,
2607 unsigned StructuredIndex,
2608 SourceRange InitRange,
2609 bool IsFullyOverwritten) {
2611 return nullptr; // No structured list in verification-only mode.
2612 Expr *ExistingInit = nullptr;
2613 if (!StructuredList)
2614 ExistingInit = SyntacticToSemantic.lookup(IList);
2615 else if (StructuredIndex < StructuredList->getNumInits())
2616 ExistingInit = StructuredList->getInit(StructuredIndex);
2618 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit))
2619 // There might have already been initializers for subobjects of the current
2620 // object, but a subsequent initializer list will overwrite the entirety
2621 // of the current object. (See DR 253 and C99 6.7.8p21). e.g.,
2623 // struct P { char x[6]; };
2624 // struct P l = { .x[2] = 'x', .x = { [0] = 'f' } };
2626 // The first designated initializer is ignored, and l.x is just "f".
2627 if (!IsFullyOverwritten)
2631 // We are creating an initializer list that initializes the
2632 // subobjects of the current object, but there was already an
2633 // initialization that completely initialized the current
2634 // subobject, e.g., by a compound literal:
2636 // struct X { int a, b; };
2637 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2639 // Here, xs[0].a == 0 and xs[0].b == 3, since the second,
2640 // designated initializer re-initializes the whole
2641 // subobject [0], overwriting previous initializers.
2642 SemaRef.Diag(InitRange.getBegin(),
2643 diag::warn_subobject_initializer_overrides)
2645 SemaRef.Diag(ExistingInit->getLocStart(),
2646 diag::note_previous_initializer)
2647 << /*FIXME:has side effects=*/0
2648 << ExistingInit->getSourceRange();
2651 InitListExpr *Result
2652 = new (SemaRef.Context) InitListExpr(SemaRef.Context,
2653 InitRange.getBegin(), None,
2654 InitRange.getEnd());
2656 QualType ResultType = CurrentObjectType;
2657 if (!ResultType->isArrayType())
2658 ResultType = ResultType.getNonLValueExprType(SemaRef.Context);
2659 Result->setType(ResultType);
2661 // Pre-allocate storage for the structured initializer list.
2662 unsigned NumElements = 0;
2663 unsigned NumInits = 0;
2664 bool GotNumInits = false;
2665 if (!StructuredList) {
2666 NumInits = IList->getNumInits();
2668 } else if (Index < IList->getNumInits()) {
2669 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) {
2670 NumInits = SubList->getNumInits();
2675 if (const ArrayType *AType
2676 = SemaRef.Context.getAsArrayType(CurrentObjectType)) {
2677 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) {
2678 NumElements = CAType->getSize().getZExtValue();
2679 // Simple heuristic so that we don't allocate a very large
2680 // initializer with many empty entries at the end.
2681 if (GotNumInits && NumElements > NumInits)
2684 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>())
2685 NumElements = VType->getNumElements();
2686 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) {
2687 RecordDecl *RDecl = RType->getDecl();
2688 if (RDecl->isUnion())
2691 NumElements = std::distance(RDecl->field_begin(), RDecl->field_end());
2694 Result->reserveInits(SemaRef.Context, NumElements);
2696 // Link this new initializer list into the structured initializer
2699 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result);
2701 Result->setSyntacticForm(IList);
2702 SyntacticToSemantic[IList] = Result;
2708 /// Update the initializer at index @p StructuredIndex within the
2709 /// structured initializer list to the value @p expr.
2710 void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList,
2711 unsigned &StructuredIndex,
2713 // No structured initializer list to update
2714 if (!StructuredList)
2717 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context,
2718 StructuredIndex, expr)) {
2719 // This initializer overwrites a previous initializer. Warn.
2720 // We need to check on source range validity because the previous
2721 // initializer does not have to be an explicit initializer.
2722 // struct P { int a, b; };
2723 // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
2724 // There is an overwrite taking place because the first braced initializer
2725 // list "{ .a = 2 }' already provides value for .p.b (which is zero).
2726 if (PrevInit->getSourceRange().isValid()) {
2727 SemaRef.Diag(expr->getLocStart(),
2728 diag::warn_initializer_overrides)
2729 << expr->getSourceRange();
2731 SemaRef.Diag(PrevInit->getLocStart(),
2732 diag::note_previous_initializer)
2733 << /*FIXME:has side effects=*/0
2734 << PrevInit->getSourceRange();
2741 /// Check that the given Index expression is a valid array designator
2742 /// value. This is essentially just a wrapper around
2743 /// VerifyIntegerConstantExpression that also checks for negative values
2744 /// and produces a reasonable diagnostic if there is a
2745 /// failure. Returns the index expression, possibly with an implicit cast
2746 /// added, on success. If everything went okay, Value will receive the
2747 /// value of the constant expression.
2749 CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) {
2750 SourceLocation Loc = Index->getLocStart();
2752 // Make sure this is an integer constant expression.
2753 ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value);
2754 if (Result.isInvalid())
2757 if (Value.isSigned() && Value.isNegative())
2758 return S.Diag(Loc, diag::err_array_designator_negative)
2759 << Value.toString(10) << Index->getSourceRange();
2761 Value.setIsUnsigned(true);
2765 ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig,
2769 typedef DesignatedInitExpr::Designator ASTDesignator;
2771 bool Invalid = false;
2772 SmallVector<ASTDesignator, 32> Designators;
2773 SmallVector<Expr *, 32> InitExpressions;
2775 // Build designators and check array designator expressions.
2776 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) {
2777 const Designator &D = Desig.getDesignator(Idx);
2778 switch (D.getKind()) {
2779 case Designator::FieldDesignator:
2780 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(),
2784 case Designator::ArrayDesignator: {
2785 Expr *Index = static_cast<Expr *>(D.getArrayIndex());
2786 llvm::APSInt IndexValue;
2787 if (!Index->isTypeDependent() && !Index->isValueDependent())
2788 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).get();
2792 Designators.push_back(ASTDesignator(InitExpressions.size(),
2794 D.getRBracketLoc()));
2795 InitExpressions.push_back(Index);
2800 case Designator::ArrayRangeDesignator: {
2801 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart());
2802 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd());
2803 llvm::APSInt StartValue;
2804 llvm::APSInt EndValue;
2805 bool StartDependent = StartIndex->isTypeDependent() ||
2806 StartIndex->isValueDependent();
2807 bool EndDependent = EndIndex->isTypeDependent() ||
2808 EndIndex->isValueDependent();
2809 if (!StartDependent)
2811 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).get();
2813 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).get();
2815 if (!StartIndex || !EndIndex)
2818 // Make sure we're comparing values with the same bit width.
2819 if (StartDependent || EndDependent) {
2820 // Nothing to compute.
2821 } else if (StartValue.getBitWidth() > EndValue.getBitWidth())
2822 EndValue = EndValue.extend(StartValue.getBitWidth());
2823 else if (StartValue.getBitWidth() < EndValue.getBitWidth())
2824 StartValue = StartValue.extend(EndValue.getBitWidth());
2826 if (!StartDependent && !EndDependent && EndValue < StartValue) {
2827 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range)
2828 << StartValue.toString(10) << EndValue.toString(10)
2829 << StartIndex->getSourceRange() << EndIndex->getSourceRange();
2832 Designators.push_back(ASTDesignator(InitExpressions.size(),
2835 D.getRBracketLoc()));
2836 InitExpressions.push_back(StartIndex);
2837 InitExpressions.push_back(EndIndex);
2845 if (Invalid || Init.isInvalid())
2848 // Clear out the expressions within the designation.
2849 Desig.ClearExprs(*this);
2851 DesignatedInitExpr *DIE
2852 = DesignatedInitExpr::Create(Context,
2854 InitExpressions, Loc, GNUSyntax,
2855 Init.getAs<Expr>());
2857 if (!getLangOpts().C99)
2858 Diag(DIE->getLocStart(), diag::ext_designated_init)
2859 << DIE->getSourceRange();
2864 //===----------------------------------------------------------------------===//
2865 // Initialization entity
2866 //===----------------------------------------------------------------------===//
2868 InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index,
2869 const InitializedEntity &Parent)
2870 : Parent(&Parent), Index(Index)
2872 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) {
2873 Kind = EK_ArrayElement;
2874 Type = AT->getElementType();
2875 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) {
2876 Kind = EK_VectorElement;
2877 Type = VT->getElementType();
2879 const ComplexType *CT = Parent.getType()->getAs<ComplexType>();
2880 assert(CT && "Unexpected type");
2881 Kind = EK_ComplexElement;
2882 Type = CT->getElementType();
2887 InitializedEntity::InitializeBase(ASTContext &Context,
2888 const CXXBaseSpecifier *Base,
2889 bool IsInheritedVirtualBase,
2890 const InitializedEntity *Parent) {
2891 InitializedEntity Result;
2892 Result.Kind = EK_Base;
2893 Result.Parent = Parent;
2894 Result.Base = reinterpret_cast<uintptr_t>(Base);
2895 if (IsInheritedVirtualBase)
2896 Result.Base |= 0x01;
2898 Result.Type = Base->getType();
2902 DeclarationName InitializedEntity::getName() const {
2903 switch (getKind()) {
2905 case EK_Parameter_CF_Audited: {
2906 ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
2907 return (D ? D->getDeclName() : DeclarationName());
2913 return Variable.VariableOrMember->getDeclName();
2915 case EK_LambdaCapture:
2916 return DeclarationName(Capture.VarID);
2924 case EK_ArrayElement:
2925 case EK_VectorElement:
2926 case EK_ComplexElement:
2927 case EK_BlockElement:
2928 case EK_CompoundLiteralInit:
2929 case EK_RelatedResult:
2930 return DeclarationName();
2933 llvm_unreachable("Invalid EntityKind!");
2936 ValueDecl *InitializedEntity::getDecl() const {
2937 switch (getKind()) {
2941 return Variable.VariableOrMember;
2944 case EK_Parameter_CF_Audited:
2945 return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
2953 case EK_ArrayElement:
2954 case EK_VectorElement:
2955 case EK_ComplexElement:
2956 case EK_BlockElement:
2957 case EK_LambdaCapture:
2958 case EK_CompoundLiteralInit:
2959 case EK_RelatedResult:
2963 llvm_unreachable("Invalid EntityKind!");
2966 bool InitializedEntity::allowsNRVO() const {
2967 switch (getKind()) {
2970 return LocAndNRVO.NRVO;
2974 case EK_Parameter_CF_Audited:
2979 case EK_CompoundLiteralInit:
2982 case EK_ArrayElement:
2983 case EK_VectorElement:
2984 case EK_ComplexElement:
2985 case EK_BlockElement:
2986 case EK_LambdaCapture:
2987 case EK_RelatedResult:
2994 unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const {
2995 assert(getParent() != this);
2996 unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0;
2997 for (unsigned I = 0; I != Depth; ++I)
3000 switch (getKind()) {
3001 case EK_Variable: OS << "Variable"; break;
3002 case EK_Parameter: OS << "Parameter"; break;
3003 case EK_Parameter_CF_Audited: OS << "CF audited function Parameter";
3005 case EK_Result: OS << "Result"; break;
3006 case EK_Exception: OS << "Exception"; break;
3007 case EK_Member: OS << "Member"; break;
3008 case EK_Binding: OS << "Binding"; break;
3009 case EK_New: OS << "New"; break;
3010 case EK_Temporary: OS << "Temporary"; break;
3011 case EK_CompoundLiteralInit: OS << "CompoundLiteral";break;
3012 case EK_RelatedResult: OS << "RelatedResult"; break;
3013 case EK_Base: OS << "Base"; break;
3014 case EK_Delegating: OS << "Delegating"; break;
3015 case EK_ArrayElement: OS << "ArrayElement " << Index; break;
3016 case EK_VectorElement: OS << "VectorElement " << Index; break;
3017 case EK_ComplexElement: OS << "ComplexElement " << Index; break;
3018 case EK_BlockElement: OS << "Block"; break;
3019 case EK_LambdaCapture:
3020 OS << "LambdaCapture ";
3021 OS << DeclarationName(Capture.VarID);
3025 if (auto *D = getDecl()) {
3027 D->printQualifiedName(OS);
3030 OS << " '" << getType().getAsString() << "'\n";
3035 LLVM_DUMP_METHOD void InitializedEntity::dump() const {
3036 dumpImpl(llvm::errs());
3039 //===----------------------------------------------------------------------===//
3040 // Initialization sequence
3041 //===----------------------------------------------------------------------===//
3043 void InitializationSequence::Step::Destroy() {
3045 case SK_ResolveAddressOfOverloadedFunction:
3046 case SK_CastDerivedToBaseRValue:
3047 case SK_CastDerivedToBaseXValue:
3048 case SK_CastDerivedToBaseLValue:
3049 case SK_BindReference:
3050 case SK_BindReferenceToTemporary:
3052 case SK_ExtraneousCopyToTemporary:
3053 case SK_UserConversion:
3054 case SK_QualificationConversionRValue:
3055 case SK_QualificationConversionXValue:
3056 case SK_QualificationConversionLValue:
3057 case SK_AtomicConversion:
3058 case SK_LValueToRValue:
3059 case SK_ListInitialization:
3060 case SK_UnwrapInitList:
3061 case SK_RewrapInitList:
3062 case SK_ConstructorInitialization:
3063 case SK_ConstructorInitializationFromList:
3064 case SK_ZeroInitialization:
3065 case SK_CAssignment:
3067 case SK_ObjCObjectConversion:
3068 case SK_ArrayLoopIndex:
3069 case SK_ArrayLoopInit:
3071 case SK_GNUArrayInit:
3072 case SK_ParenthesizedArrayInit:
3073 case SK_PassByIndirectCopyRestore:
3074 case SK_PassByIndirectRestore:
3075 case SK_ProduceObjCObject:
3076 case SK_StdInitializerList:
3077 case SK_StdInitializerListConstructorCall:
3078 case SK_OCLSamplerInit:
3079 case SK_OCLZeroEvent:
3080 case SK_OCLZeroQueue:
3083 case SK_ConversionSequence:
3084 case SK_ConversionSequenceNoNarrowing:
3089 bool InitializationSequence::isDirectReferenceBinding() const {
3090 // There can be some lvalue adjustments after the SK_BindReference step.
3091 for (auto I = Steps.rbegin(); I != Steps.rend(); ++I) {
3092 if (I->Kind == SK_BindReference)
3094 if (I->Kind == SK_BindReferenceToTemporary)
3100 bool InitializationSequence::isAmbiguous() const {
3104 switch (getFailureKind()) {
3105 case FK_TooManyInitsForReference:
3106 case FK_ArrayNeedsInitList:
3107 case FK_ArrayNeedsInitListOrStringLiteral:
3108 case FK_ArrayNeedsInitListOrWideStringLiteral:
3109 case FK_NarrowStringIntoWideCharArray:
3110 case FK_WideStringIntoCharArray:
3111 case FK_IncompatWideStringIntoWideChar:
3112 case FK_AddressOfOverloadFailed: // FIXME: Could do better
3113 case FK_NonConstLValueReferenceBindingToTemporary:
3114 case FK_NonConstLValueReferenceBindingToBitfield:
3115 case FK_NonConstLValueReferenceBindingToVectorElement:
3116 case FK_NonConstLValueReferenceBindingToUnrelated:
3117 case FK_RValueReferenceBindingToLValue:
3118 case FK_ReferenceInitDropsQualifiers:
3119 case FK_ReferenceInitFailed:
3120 case FK_ConversionFailed:
3121 case FK_ConversionFromPropertyFailed:
3122 case FK_TooManyInitsForScalar:
3123 case FK_ReferenceBindingToInitList:
3124 case FK_InitListBadDestinationType:
3125 case FK_DefaultInitOfConst:
3127 case FK_ArrayTypeMismatch:
3128 case FK_NonConstantArrayInit:
3129 case FK_ListInitializationFailed:
3130 case FK_VariableLengthArrayHasInitializer:
3131 case FK_PlaceholderType:
3132 case FK_ExplicitConstructor:
3133 case FK_AddressOfUnaddressableFunction:
3136 case FK_ReferenceInitOverloadFailed:
3137 case FK_UserConversionOverloadFailed:
3138 case FK_ConstructorOverloadFailed:
3139 case FK_ListConstructorOverloadFailed:
3140 return FailedOverloadResult == OR_Ambiguous;
3143 llvm_unreachable("Invalid EntityKind!");
3146 bool InitializationSequence::isConstructorInitialization() const {
3147 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization;
3151 InitializationSequence
3152 ::AddAddressOverloadResolutionStep(FunctionDecl *Function,
3153 DeclAccessPair Found,
3154 bool HadMultipleCandidates) {
3156 S.Kind = SK_ResolveAddressOfOverloadedFunction;
3157 S.Type = Function->getType();
3158 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3159 S.Function.Function = Function;
3160 S.Function.FoundDecl = Found;
3164 void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType,
3168 case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break;
3169 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break;
3170 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break;
3176 void InitializationSequence::AddReferenceBindingStep(QualType T,
3177 bool BindingTemporary) {
3179 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference;
3184 void InitializationSequence::AddFinalCopy(QualType T) {
3186 S.Kind = SK_FinalCopy;
3191 void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) {
3193 S.Kind = SK_ExtraneousCopyToTemporary;
3199 InitializationSequence::AddUserConversionStep(FunctionDecl *Function,
3200 DeclAccessPair FoundDecl,
3202 bool HadMultipleCandidates) {
3204 S.Kind = SK_UserConversion;
3206 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3207 S.Function.Function = Function;
3208 S.Function.FoundDecl = FoundDecl;
3212 void InitializationSequence::AddQualificationConversionStep(QualType Ty,
3215 S.Kind = SK_QualificationConversionRValue; // work around a gcc warning
3218 S.Kind = SK_QualificationConversionRValue;
3221 S.Kind = SK_QualificationConversionXValue;
3224 S.Kind = SK_QualificationConversionLValue;
3231 void InitializationSequence::AddAtomicConversionStep(QualType Ty) {
3233 S.Kind = SK_AtomicConversion;
3238 void InitializationSequence::AddLValueToRValueStep(QualType Ty) {
3239 assert(!Ty.hasQualifiers() && "rvalues may not have qualifiers");
3242 S.Kind = SK_LValueToRValue;
3247 void InitializationSequence::AddConversionSequenceStep(
3248 const ImplicitConversionSequence &ICS, QualType T,
3249 bool TopLevelOfInitList) {
3251 S.Kind = TopLevelOfInitList ? SK_ConversionSequenceNoNarrowing
3252 : SK_ConversionSequence;
3254 S.ICS = new ImplicitConversionSequence(ICS);
3258 void InitializationSequence::AddListInitializationStep(QualType T) {
3260 S.Kind = SK_ListInitialization;
3265 void InitializationSequence::AddConstructorInitializationStep(
3266 DeclAccessPair FoundDecl, CXXConstructorDecl *Constructor, QualType T,
3267 bool HadMultipleCandidates, bool FromInitList, bool AsInitList) {
3269 S.Kind = FromInitList ? AsInitList ? SK_StdInitializerListConstructorCall
3270 : SK_ConstructorInitializationFromList
3271 : SK_ConstructorInitialization;
3273 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3274 S.Function.Function = Constructor;
3275 S.Function.FoundDecl = FoundDecl;
3279 void InitializationSequence::AddZeroInitializationStep(QualType T) {
3281 S.Kind = SK_ZeroInitialization;
3286 void InitializationSequence::AddCAssignmentStep(QualType T) {
3288 S.Kind = SK_CAssignment;
3293 void InitializationSequence::AddStringInitStep(QualType T) {
3295 S.Kind = SK_StringInit;
3300 void InitializationSequence::AddObjCObjectConversionStep(QualType T) {
3302 S.Kind = SK_ObjCObjectConversion;
3307 void InitializationSequence::AddArrayInitStep(QualType T, bool IsGNUExtension) {
3309 S.Kind = IsGNUExtension ? SK_GNUArrayInit : SK_ArrayInit;
3314 void InitializationSequence::AddArrayInitLoopStep(QualType T, QualType EltT) {
3316 S.Kind = SK_ArrayLoopIndex;
3318 Steps.insert(Steps.begin(), S);
3320 S.Kind = SK_ArrayLoopInit;
3325 void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) {
3327 S.Kind = SK_ParenthesizedArrayInit;
3332 void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type,
3335 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore
3336 : SK_PassByIndirectRestore);
3341 void InitializationSequence::AddProduceObjCObjectStep(QualType T) {
3343 S.Kind = SK_ProduceObjCObject;
3348 void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
3350 S.Kind = SK_StdInitializerList;
3355 void InitializationSequence::AddOCLSamplerInitStep(QualType T) {
3357 S.Kind = SK_OCLSamplerInit;
3362 void InitializationSequence::AddOCLZeroEventStep(QualType T) {
3364 S.Kind = SK_OCLZeroEvent;
3369 void InitializationSequence::AddOCLZeroQueueStep(QualType T) {
3371 S.Kind = SK_OCLZeroQueue;
3376 void InitializationSequence::RewrapReferenceInitList(QualType T,
3377 InitListExpr *Syntactic) {
3378 assert(Syntactic->getNumInits() == 1 &&
3379 "Can only rewrap trivial init lists.");
3381 S.Kind = SK_UnwrapInitList;
3382 S.Type = Syntactic->getInit(0)->getType();
3383 Steps.insert(Steps.begin(), S);
3385 S.Kind = SK_RewrapInitList;
3387 S.WrappingSyntacticList = Syntactic;
3391 void InitializationSequence::SetOverloadFailure(FailureKind Failure,
3392 OverloadingResult Result) {
3393 setSequenceKind(FailedSequence);
3394 this->Failure = Failure;
3395 this->FailedOverloadResult = Result;
3398 //===----------------------------------------------------------------------===//
3399 // Attempt initialization
3400 //===----------------------------------------------------------------------===//
3402 /// Tries to add a zero initializer. Returns true if that worked.
3404 maybeRecoverWithZeroInitialization(Sema &S, InitializationSequence &Sequence,
3405 const InitializedEntity &Entity) {
3406 if (Entity.getKind() != InitializedEntity::EK_Variable)
3409 VarDecl *VD = cast<VarDecl>(Entity.getDecl());
3410 if (VD->getInit() || VD->getLocEnd().isMacroID())
3413 QualType VariableTy = VD->getType().getCanonicalType();
3414 SourceLocation Loc = S.getLocForEndOfToken(VD->getLocEnd());
3415 std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
3416 if (!Init.empty()) {
3417 Sequence.AddZeroInitializationStep(Entity.getType());
3418 Sequence.SetZeroInitializationFixit(Init, Loc);
3424 static void MaybeProduceObjCObject(Sema &S,
3425 InitializationSequence &Sequence,
3426 const InitializedEntity &Entity) {
3427 if (!S.getLangOpts().ObjCAutoRefCount) return;
3429 /// When initializing a parameter, produce the value if it's marked
3430 /// __attribute__((ns_consumed)).
3431 if (Entity.isParameterKind()) {
3432 if (!Entity.isParameterConsumed())
3435 assert(Entity.getType()->isObjCRetainableType() &&
3436 "consuming an object of unretainable type?");
3437 Sequence.AddProduceObjCObjectStep(Entity.getType());
3439 /// When initializing a return value, if the return type is a
3440 /// retainable type, then returns need to immediately retain the
3441 /// object. If an autorelease is required, it will be done at the
3443 } else if (Entity.getKind() == InitializedEntity::EK_Result) {
3444 if (!Entity.getType()->isObjCRetainableType())
3447 Sequence.AddProduceObjCObjectStep(Entity.getType());
3451 static void TryListInitialization(Sema &S,
3452 const InitializedEntity &Entity,
3453 const InitializationKind &Kind,
3454 InitListExpr *InitList,
3455 InitializationSequence &Sequence,
3456 bool TreatUnavailableAsInvalid);
3458 /// \brief When initializing from init list via constructor, handle
3459 /// initialization of an object of type std::initializer_list<T>.
3461 /// \return true if we have handled initialization of an object of type
3462 /// std::initializer_list<T>, false otherwise.
3463 static bool TryInitializerListConstruction(Sema &S,
3466 InitializationSequence &Sequence,
3467 bool TreatUnavailableAsInvalid) {
3469 if (!S.isStdInitializerList(DestType, &E))
3472 if (!S.isCompleteType(List->getExprLoc(), E)) {
3473 Sequence.setIncompleteTypeFailure(E);
3477 // Try initializing a temporary array from the init list.
3478 QualType ArrayType = S.Context.getConstantArrayType(
3479 E.withConst(), llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
3480 List->getNumInits()),
3481 clang::ArrayType::Normal, 0);
3482 InitializedEntity HiddenArray =
3483 InitializedEntity::InitializeTemporary(ArrayType);
3484 InitializationKind Kind =
3485 InitializationKind::CreateDirectList(List->getExprLoc());
3486 TryListInitialization(S, HiddenArray, Kind, List, Sequence,
3487 TreatUnavailableAsInvalid);
3489 Sequence.AddStdInitializerListConstructionStep(DestType);
3493 /// Determine if the constructor has the signature of a copy or move
3494 /// constructor for the type T of the class in which it was found. That is,
3495 /// determine if its first parameter is of type T or reference to (possibly
3496 /// cv-qualified) T.
3497 static bool hasCopyOrMoveCtorParam(ASTContext &Ctx,
3498 const ConstructorInfo &Info) {
3499 if (Info.Constructor->getNumParams() == 0)
3503 Info.Constructor->getParamDecl(0)->getType().getNonReferenceType();
3505 Ctx.getRecordType(cast<CXXRecordDecl>(Info.FoundDecl->getDeclContext()));
3507 return Ctx.hasSameUnqualifiedType(ParmT, ClassT);
3510 static OverloadingResult
3511 ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc,
3513 OverloadCandidateSet &CandidateSet,
3514 DeclContext::lookup_result Ctors,
3515 OverloadCandidateSet::iterator &Best,
3516 bool CopyInitializing, bool AllowExplicit,
3517 bool OnlyListConstructors, bool IsListInit,
3518 bool SecondStepOfCopyInit = false) {
3519 CandidateSet.clear();
3521 for (NamedDecl *D : Ctors) {
3522 auto Info = getConstructorInfo(D);
3523 if (!Info.Constructor || Info.Constructor->isInvalidDecl())
3526 if (!AllowExplicit && Info.Constructor->isExplicit())
3529 if (OnlyListConstructors && !S.isInitListConstructor(Info.Constructor))
3532 // C++11 [over.best.ics]p4:
3533 // ... and the constructor or user-defined conversion function is a
3535 // - 13.3.1.3, when the argument is the temporary in the second step
3536 // of a class copy-initialization, or
3537 // - 13.3.1.4, 13.3.1.5, or 13.3.1.6 (in all cases), [not handled here]
3538 // - the second phase of 13.3.1.7 when the initializer list has exactly
3539 // one element that is itself an initializer list, and the target is
3540 // the first parameter of a constructor of class X, and the conversion
3541 // is to X or reference to (possibly cv-qualified X),
3542 // user-defined conversion sequences are not considered.
3543 bool SuppressUserConversions =
3544 SecondStepOfCopyInit ||
3545 (IsListInit && Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
3546 hasCopyOrMoveCtorParam(S.Context, Info));
3548 if (Info.ConstructorTmpl)
3549 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
3550 /*ExplicitArgs*/ nullptr, Args,
3551 CandidateSet, SuppressUserConversions);
3553 // C++ [over.match.copy]p1:
3554 // - When initializing a temporary to be bound to the first parameter
3555 // of a constructor [for type T] that takes a reference to possibly
3556 // cv-qualified T as its first argument, called with a single
3557 // argument in the context of direct-initialization, explicit
3558 // conversion functions are also considered.
3559 // FIXME: What if a constructor template instantiates to such a signature?
3560 bool AllowExplicitConv = AllowExplicit && !CopyInitializing &&
3562 hasCopyOrMoveCtorParam(S.Context, Info);
3563 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, Args,
3564 CandidateSet, SuppressUserConversions,
3565 /*PartialOverloading=*/false,
3566 /*AllowExplicit=*/AllowExplicitConv);
3570 // Perform overload resolution and return the result.
3571 return CandidateSet.BestViableFunction(S, DeclLoc, Best);
3574 /// \brief Attempt initialization by constructor (C++ [dcl.init]), which
3575 /// enumerates the constructors of the initialized entity and performs overload
3576 /// resolution to select the best.
3577 /// \param DestType The destination class type.
3578 /// \param DestArrayType The destination type, which is either DestType or
3579 /// a (possibly multidimensional) array of DestType.
3580 /// \param IsListInit Is this list-initialization?
3581 /// \param IsInitListCopy Is this non-list-initialization resulting from a
3582 /// list-initialization from {x} where x is the same
3583 /// type as the entity?
3584 static void TryConstructorInitialization(Sema &S,
3585 const InitializedEntity &Entity,
3586 const InitializationKind &Kind,
3587 MultiExprArg Args, QualType DestType,
3588 QualType DestArrayType,
3589 InitializationSequence &Sequence,
3590 bool IsListInit = false,
3591 bool IsInitListCopy = false) {
3592 assert(((!IsListInit && !IsInitListCopy) ||
3593 (Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&
3594 "IsListInit/IsInitListCopy must come with a single initializer list "
3597 (IsListInit || IsInitListCopy) ? cast<InitListExpr>(Args[0]) : nullptr;
3598 MultiExprArg UnwrappedArgs =
3599 ILE ? MultiExprArg(ILE->getInits(), ILE->getNumInits()) : Args;
3601 // The type we're constructing needs to be complete.
3602 if (!S.isCompleteType(Kind.getLocation(), DestType)) {
3603 Sequence.setIncompleteTypeFailure(DestType);
3607 // C++1z [dcl.init]p17:
3608 // - If the initializer expression is a prvalue and the cv-unqualified
3609 // version of the source type is the same class as the class of the
3610 // destination, the initializer expression is used to initialize the
3611 // destination object.
3612 // Per DR (no number yet), this does not apply when initializing a base
3613 // class or delegating to another constructor from a mem-initializer.
3614 if (S.getLangOpts().CPlusPlus1z &&
3615 Entity.getKind() != InitializedEntity::EK_Base &&
3616 Entity.getKind() != InitializedEntity::EK_Delegating &&
3617 UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isRValue() &&
3618 S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) {
3619 // Convert qualifications if necessary.
3620 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
3622 Sequence.RewrapReferenceInitList(DestType, ILE);
3626 const RecordType *DestRecordType = DestType->getAs<RecordType>();
3627 assert(DestRecordType && "Constructor initialization requires record type");
3628 CXXRecordDecl *DestRecordDecl
3629 = cast<CXXRecordDecl>(DestRecordType->getDecl());
3631 // Build the candidate set directly in the initialization sequence
3632 // structure, so that it will persist if we fail.
3633 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
3635 // Determine whether we are allowed to call explicit constructors or
3636 // explicit conversion operators.
3637 bool AllowExplicit = Kind.AllowExplicit() || IsListInit;
3638 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy;
3640 // - Otherwise, if T is a class type, constructors are considered. The
3641 // applicable constructors are enumerated, and the best one is chosen
3642 // through overload resolution.
3643 DeclContext::lookup_result Ctors = S.LookupConstructors(DestRecordDecl);
3645 OverloadingResult Result = OR_No_Viable_Function;
3646 OverloadCandidateSet::iterator Best;
3647 bool AsInitializerList = false;
3649 // C++11 [over.match.list]p1, per DR1467:
3650 // When objects of non-aggregate type T are list-initialized, such that
3651 // 8.5.4 [dcl.init.list] specifies that overload resolution is performed
3652 // according to the rules in this section, overload resolution selects
3653 // the constructor in two phases:
3655 // - Initially, the candidate functions are the initializer-list
3656 // constructors of the class T and the argument list consists of the
3657 // initializer list as a single argument.
3659 AsInitializerList = true;
3661 // If the initializer list has no elements and T has a default constructor,
3662 // the first phase is omitted.
3663 if (!(UnwrappedArgs.empty() && DestRecordDecl->hasDefaultConstructor()))
3664 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
3665 CandidateSet, Ctors, Best,
3666 CopyInitialization, AllowExplicit,
3667 /*OnlyListConstructor=*/true,
3671 // C++11 [over.match.list]p1:
3672 // - If no viable initializer-list constructor is found, overload resolution
3673 // is performed again, where the candidate functions are all the
3674 // constructors of the class T and the argument list consists of the
3675 // elements of the initializer list.
3676 if (Result == OR_No_Viable_Function) {
3677 AsInitializerList = false;
3678 Result = ResolveConstructorOverload(S, Kind.getLocation(), UnwrappedArgs,
3679 CandidateSet, Ctors, Best,
3680 CopyInitialization, AllowExplicit,
3681 /*OnlyListConstructors=*/false,
3685 Sequence.SetOverloadFailure(IsListInit ?
3686 InitializationSequence::FK_ListConstructorOverloadFailed :
3687 InitializationSequence::FK_ConstructorOverloadFailed,
3692 // C++11 [dcl.init]p6:
3693 // If a program calls for the default initialization of an object
3694 // of a const-qualified type T, T shall be a class type with a
3695 // user-provided default constructor.
3696 // C++ core issue 253 proposal:
3697 // If the implicit default constructor initializes all subobjects, no
3698 // initializer should be required.
3699 // The 253 proposal is for example needed to process libstdc++ headers in 5.x.
3700 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
3701 if (Kind.getKind() == InitializationKind::IK_Default &&
3702 Entity.getType().isConstQualified()) {
3703 if (!CtorDecl->getParent()->allowConstDefaultInit()) {
3704 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
3705 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
3710 // C++11 [over.match.list]p1:
3711 // In copy-list-initialization, if an explicit constructor is chosen, the
3712 // initializer is ill-formed.
3713 if (IsListInit && !Kind.AllowExplicit() && CtorDecl->isExplicit()) {
3714 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor);
3718 // Add the constructor initialization step. Any cv-qualification conversion is
3719 // subsumed by the initialization.
3720 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3721 Sequence.AddConstructorInitializationStep(
3722 Best->FoundDecl, CtorDecl, DestArrayType, HadMultipleCandidates,
3723 IsListInit | IsInitListCopy, AsInitializerList);
3727 ResolveOverloadedFunctionForReferenceBinding(Sema &S,
3729 QualType &SourceType,
3730 QualType &UnqualifiedSourceType,
3731 QualType UnqualifiedTargetType,
3732 InitializationSequence &Sequence) {
3733 if (S.Context.getCanonicalType(UnqualifiedSourceType) ==
3734 S.Context.OverloadTy) {
3735 DeclAccessPair Found;
3736 bool HadMultipleCandidates = false;
3737 if (FunctionDecl *Fn
3738 = S.ResolveAddressOfOverloadedFunction(Initializer,
3739 UnqualifiedTargetType,
3741 &HadMultipleCandidates)) {
3742 Sequence.AddAddressOverloadResolutionStep(Fn, Found,
3743 HadMultipleCandidates);
3744 SourceType = Fn->getType();
3745 UnqualifiedSourceType = SourceType.getUnqualifiedType();
3746 } else if (!UnqualifiedTargetType->isRecordType()) {
3747 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
3754 static void TryReferenceInitializationCore(Sema &S,
3755 const InitializedEntity &Entity,
3756 const InitializationKind &Kind,
3758 QualType cv1T1, QualType T1,
3760 QualType cv2T2, QualType T2,
3762 InitializationSequence &Sequence);
3764 static void TryValueInitialization(Sema &S,
3765 const InitializedEntity &Entity,
3766 const InitializationKind &Kind,
3767 InitializationSequence &Sequence,
3768 InitListExpr *InitList = nullptr);
3770 /// \brief Attempt list initialization of a reference.
3771 static void TryReferenceListInitialization(Sema &S,
3772 const InitializedEntity &Entity,
3773 const InitializationKind &Kind,
3774 InitListExpr *InitList,
3775 InitializationSequence &Sequence,
3776 bool TreatUnavailableAsInvalid) {
3777 // First, catch C++03 where this isn't possible.
3778 if (!S.getLangOpts().CPlusPlus11) {
3779 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
3782 // Can't reference initialize a compound literal.
3783 if (Entity.getKind() == InitializedEntity::EK_CompoundLiteralInit) {
3784 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
3788 QualType DestType = Entity.getType();
3789 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
3791 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
3793 // Reference initialization via an initializer list works thus:
3794 // If the initializer list consists of a single element that is
3795 // reference-related to the referenced type, bind directly to that element
3796 // (possibly creating temporaries).
3797 // Otherwise, initialize a temporary with the initializer list and
3799 if (InitList->getNumInits() == 1) {
3800 Expr *Initializer = InitList->getInit(0);
3801 QualType cv2T2 = Initializer->getType();
3803 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
3805 // If this fails, creating a temporary wouldn't work either.
3806 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
3810 SourceLocation DeclLoc = Initializer->getLocStart();
3811 bool dummy1, dummy2, dummy3;
3812 Sema::ReferenceCompareResult RefRelationship
3813 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1,
3815 if (RefRelationship >= Sema::Ref_Related) {
3816 // Try to bind the reference here.
3817 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
3818 T1Quals, cv2T2, T2, T2Quals, Sequence);
3820 Sequence.RewrapReferenceInitList(cv1T1, InitList);
3824 // Update the initializer if we've resolved an overloaded function.
3825 if (Sequence.step_begin() != Sequence.step_end())
3826 Sequence.RewrapReferenceInitList(cv1T1, InitList);
3829 // Not reference-related. Create a temporary and bind to that.
3830 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
3832 TryListInitialization(S, TempEntity, Kind, InitList, Sequence,
3833 TreatUnavailableAsInvalid);
3835 if (DestType->isRValueReferenceType() ||
3836 (T1Quals.hasConst() && !T1Quals.hasVolatile()))
3837 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
3840 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
3844 /// \brief Attempt list initialization (C++0x [dcl.init.list])
3845 static void TryListInitialization(Sema &S,
3846 const InitializedEntity &Entity,
3847 const InitializationKind &Kind,
3848 InitListExpr *InitList,
3849 InitializationSequence &Sequence,
3850 bool TreatUnavailableAsInvalid) {
3851 QualType DestType = Entity.getType();
3853 // C++ doesn't allow scalar initialization with more than one argument.
3854 // But C99 complex numbers are scalars and it makes sense there.
3855 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() &&
3856 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) {
3857 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar);
3860 if (DestType->isReferenceType()) {
3861 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence,
3862 TreatUnavailableAsInvalid);
3866 if (DestType->isRecordType() &&
3867 !S.isCompleteType(InitList->getLocStart(), DestType)) {
3868 Sequence.setIncompleteTypeFailure(DestType);
3872 // C++11 [dcl.init.list]p3, per DR1467:
3873 // - If T is a class type and the initializer list has a single element of
3874 // type cv U, where U is T or a class derived from T, the object is
3875 // initialized from that element (by copy-initialization for
3876 // copy-list-initialization, or by direct-initialization for
3877 // direct-list-initialization).
3878 // - Otherwise, if T is a character array and the initializer list has a
3879 // single element that is an appropriately-typed string literal
3880 // (8.5.2 [dcl.init.string]), initialization is performed as described
3882 // - Otherwise, if T is an aggregate, [...] (continue below).
3883 if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1) {
3884 if (DestType->isRecordType()) {
3885 QualType InitType = InitList->getInit(0)->getType();
3886 if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
3887 S.IsDerivedFrom(InitList->getLocStart(), InitType, DestType)) {
3888 Expr *InitListAsExpr = InitList;
3889 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
3891 /*InitListSyntax*/false,
3892 /*IsInitListCopy*/true);
3896 if (const ArrayType *DestAT = S.Context.getAsArrayType(DestType)) {
3897 Expr *SubInit[1] = {InitList->getInit(0)};
3898 if (!isa<VariableArrayType>(DestAT) &&
3899 IsStringInit(SubInit[0], DestAT, S.Context) == SIF_None) {
3900 InitializationKind SubKind =
3901 Kind.getKind() == InitializationKind::IK_DirectList
3902 ? InitializationKind::CreateDirect(Kind.getLocation(),
3903 InitList->getLBraceLoc(),
3904 InitList->getRBraceLoc())
3906 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
3907 /*TopLevelOfInitList*/ true,
3908 TreatUnavailableAsInvalid);
3910 // TryStringLiteralInitialization() (in InitializeFrom()) will fail if
3911 // the element is not an appropriately-typed string literal, in which
3912 // case we should proceed as in C++11 (below).
3914 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
3921 // C++11 [dcl.init.list]p3:
3922 // - If T is an aggregate, aggregate initialization is performed.
3923 if ((DestType->isRecordType() && !DestType->isAggregateType()) ||
3924 (S.getLangOpts().CPlusPlus11 &&
3925 S.isStdInitializerList(DestType, nullptr))) {
3926 if (S.getLangOpts().CPlusPlus11) {
3927 // - Otherwise, if the initializer list has no elements and T is a
3928 // class type with a default constructor, the object is
3929 // value-initialized.
3930 if (InitList->getNumInits() == 0) {
3931 CXXRecordDecl *RD = DestType->getAsCXXRecordDecl();
3932 if (RD->hasDefaultConstructor()) {
3933 TryValueInitialization(S, Entity, Kind, Sequence, InitList);
3938 // - Otherwise, if T is a specialization of std::initializer_list<E>,
3939 // an initializer_list object constructed [...]
3940 if (TryInitializerListConstruction(S, InitList, DestType, Sequence,
3941 TreatUnavailableAsInvalid))
3944 // - Otherwise, if T is a class type, constructors are considered.
3945 Expr *InitListAsExpr = InitList;
3946 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
3947 DestType, Sequence, /*InitListSyntax*/true);
3949 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType);
3953 if (S.getLangOpts().CPlusPlus && !DestType->isAggregateType() &&
3954 InitList->getNumInits() == 1) {
3955 Expr *E = InitList->getInit(0);
3957 // - Otherwise, if T is an enumeration with a fixed underlying type,
3958 // the initializer-list has a single element v, and the initialization
3959 // is direct-list-initialization, the object is initialized with the
3960 // value T(v); if a narrowing conversion is required to convert v to
3961 // the underlying type of T, the program is ill-formed.
3962 auto *ET = DestType->getAs<EnumType>();
3963 if (S.getLangOpts().CPlusPlus1z &&
3964 Kind.getKind() == InitializationKind::IK_DirectList &&
3965 ET && ET->getDecl()->isFixed() &&
3966 !S.Context.hasSameUnqualifiedType(E->getType(), DestType) &&
3967 (E->getType()->isIntegralOrEnumerationType() ||
3968 E->getType()->isFloatingType())) {
3969 // There are two ways that T(v) can work when T is an enumeration type.
3970 // If there is either an implicit conversion sequence from v to T or
3971 // a conversion function that can convert from v to T, then we use that.
3972 // Otherwise, if v is of integral, enumeration, or floating-point type,
3973 // it is converted to the enumeration type via its underlying type.
3974 // There is no overlap possible between these two cases (except when the
3975 // source value is already of the destination type), and the first
3976 // case is handled by the general case for single-element lists below.
3977 ImplicitConversionSequence ICS;
3979 ICS.Standard.setAsIdentityConversion();
3980 // If E is of a floating-point type, then the conversion is ill-formed
3981 // due to narrowing, but go through the motions in order to produce the
3982 // right diagnostic.
3983 ICS.Standard.Second = E->getType()->isFloatingType()
3984 ? ICK_Floating_Integral
3985 : ICK_Integral_Conversion;
3986 ICS.Standard.setFromType(E->getType());
3987 ICS.Standard.setToType(0, E->getType());
3988 ICS.Standard.setToType(1, DestType);
3989 ICS.Standard.setToType(2, DestType);
3990 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2),
3991 /*TopLevelOfInitList*/true);
3992 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
3996 // - Otherwise, if the initializer list has a single element of type E
3997 // [...references are handled above...], the object or reference is
3998 // initialized from that element (by copy-initialization for
3999 // copy-list-initialization, or by direct-initialization for
4000 // direct-list-initialization); if a narrowing conversion is required
4001 // to convert the element to T, the program is ill-formed.
4003 // Per core-24034, this is direct-initialization if we were performing
4004 // direct-list-initialization and copy-initialization otherwise.
4005 // We can't use InitListChecker for this, because it always performs
4006 // copy-initialization. This only matters if we might use an 'explicit'
4007 // conversion operator, so we only need to handle the cases where the source
4008 // is of record type.
4009 if (InitList->getInit(0)->getType()->isRecordType()) {
4010 InitializationKind SubKind =
4011 Kind.getKind() == InitializationKind::IK_DirectList
4012 ? InitializationKind::CreateDirect(Kind.getLocation(),
4013 InitList->getLBraceLoc(),
4014 InitList->getRBraceLoc())
4016 Expr *SubInit[1] = { InitList->getInit(0) };
4017 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
4018 /*TopLevelOfInitList*/true,
4019 TreatUnavailableAsInvalid);
4021 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4026 InitListChecker CheckInitList(S, Entity, InitList,
4027 DestType, /*VerifyOnly=*/true, TreatUnavailableAsInvalid);
4028 if (CheckInitList.HadError()) {
4029 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed);
4033 // Add the list initialization step with the built init list.
4034 Sequence.AddListInitializationStep(DestType);
4037 /// \brief Try a reference initialization that involves calling a conversion
4039 static OverloadingResult TryRefInitWithConversionFunction(
4040 Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
4041 Expr *Initializer, bool AllowRValues, bool IsLValueRef,
4042 InitializationSequence &Sequence) {
4043 QualType DestType = Entity.getType();
4044 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
4045 QualType T1 = cv1T1.getUnqualifiedType();
4046 QualType cv2T2 = Initializer->getType();
4047 QualType T2 = cv2T2.getUnqualifiedType();
4050 bool ObjCConversion;
4051 bool ObjCLifetimeConversion;
4052 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(),
4053 T1, T2, DerivedToBase,
4055 ObjCLifetimeConversion) &&
4056 "Must have incompatible references when binding via conversion");
4057 (void)DerivedToBase;
4058 (void)ObjCConversion;
4059 (void)ObjCLifetimeConversion;
4061 // Build the candidate set directly in the initialization sequence
4062 // structure, so that it will persist if we fail.
4063 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4064 CandidateSet.clear();
4066 // Determine whether we are allowed to call explicit constructors or
4067 // explicit conversion operators.
4068 bool AllowExplicit = Kind.AllowExplicit();
4069 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctionsInRefBinding();
4071 const RecordType *T1RecordType = nullptr;
4072 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) &&
4073 S.isCompleteType(Kind.getLocation(), T1)) {
4074 // The type we're converting to is a class type. Enumerate its constructors
4075 // to see if there is a suitable conversion.
4076 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl());
4078 for (NamedDecl *D : S.LookupConstructors(T1RecordDecl)) {
4079 auto Info = getConstructorInfo(D);
4080 if (!Info.Constructor)
4083 if (!Info.Constructor->isInvalidDecl() &&
4084 Info.Constructor->isConvertingConstructor(AllowExplicit)) {
4085 if (Info.ConstructorTmpl)
4086 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
4087 /*ExplicitArgs*/ nullptr,
4088 Initializer, CandidateSet,
4089 /*SuppressUserConversions=*/true);
4091 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
4092 Initializer, CandidateSet,
4093 /*SuppressUserConversions=*/true);
4097 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl())
4098 return OR_No_Viable_Function;
4100 const RecordType *T2RecordType = nullptr;
4101 if ((T2RecordType = T2->getAs<RecordType>()) &&
4102 S.isCompleteType(Kind.getLocation(), T2)) {
4103 // The type we're converting from is a class type, enumerate its conversion
4105 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
4107 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
4108 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4110 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4111 if (isa<UsingShadowDecl>(D))
4112 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4114 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4115 CXXConversionDecl *Conv;
4117 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4119 Conv = cast<CXXConversionDecl>(D);
4121 // If the conversion function doesn't return a reference type,
4122 // it can't be considered for this conversion unless we're allowed to
4123 // consider rvalues.
4124 // FIXME: Do we need to make sure that we only consider conversion
4125 // candidates with reference-compatible results? That might be needed to
4127 if ((AllowExplicitConvs || !Conv->isExplicit()) &&
4128 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){
4130 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(),
4131 ActingDC, Initializer,
4132 DestType, CandidateSet,
4133 /*AllowObjCConversionOnExplicit=*/
4136 S.AddConversionCandidate(Conv, I.getPair(), ActingDC,
4137 Initializer, DestType, CandidateSet,
4138 /*AllowObjCConversionOnExplicit=*/false);
4142 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl())
4143 return OR_No_Viable_Function;
4145 SourceLocation DeclLoc = Initializer->getLocStart();
4147 // Perform overload resolution. If it fails, return the failed result.
4148 OverloadCandidateSet::iterator Best;
4149 if (OverloadingResult Result
4150 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true))
4153 FunctionDecl *Function = Best->Function;
4154 // This is the overload that will be used for this initialization step if we
4155 // use this initialization. Mark it as referenced.
4156 Function->setReferenced();
4158 // Compute the returned type and value kind of the conversion.
4160 if (isa<CXXConversionDecl>(Function))
4161 cv3T3 = Function->getReturnType();
4165 ExprValueKind VK = VK_RValue;
4166 if (cv3T3->isLValueReferenceType())
4168 else if (const auto *RRef = cv3T3->getAs<RValueReferenceType>())
4169 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue;
4170 cv3T3 = cv3T3.getNonLValueExprType(S.Context);
4172 // Add the user-defined conversion step.
4173 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4174 Sequence.AddUserConversionStep(Function, Best->FoundDecl, cv3T3,
4175 HadMultipleCandidates);
4177 // Determine whether we'll need to perform derived-to-base adjustments or
4178 // other conversions.
4179 bool NewDerivedToBase = false;
4180 bool NewObjCConversion = false;
4181 bool NewObjCLifetimeConversion = false;
4182 Sema::ReferenceCompareResult NewRefRelationship
4183 = S.CompareReferenceRelationship(DeclLoc, T1, cv3T3,
4184 NewDerivedToBase, NewObjCConversion,
4185 NewObjCLifetimeConversion);
4187 // Add the final conversion sequence, if necessary.
4188 if (NewRefRelationship == Sema::Ref_Incompatible) {
4189 assert(!isa<CXXConstructorDecl>(Function) &&
4190 "should not have conversion after constructor");
4192 ImplicitConversionSequence ICS;
4194 ICS.Standard = Best->FinalConversion;
4195 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2));
4197 // Every implicit conversion results in a prvalue, except for a glvalue
4198 // derived-to-base conversion, which we handle below.
4199 cv3T3 = ICS.Standard.getToType(2);
4203 // If the converted initializer is a prvalue, its type T4 is adjusted to
4204 // type "cv1 T4" and the temporary materialization conversion is applied.
4206 // We adjust the cv-qualifications to match the reference regardless of
4207 // whether we have a prvalue so that the AST records the change. In this
4208 // case, T4 is "cv3 T3".
4209 QualType cv1T4 = S.Context.getQualifiedType(cv3T3, cv1T1.getQualifiers());
4210 if (cv1T4.getQualifiers() != cv3T3.getQualifiers())
4211 Sequence.AddQualificationConversionStep(cv1T4, VK);
4212 Sequence.AddReferenceBindingStep(cv1T4, VK == VK_RValue);
4213 VK = IsLValueRef ? VK_LValue : VK_XValue;
4215 if (NewDerivedToBase)
4216 Sequence.AddDerivedToBaseCastStep(cv1T1, VK);
4217 else if (NewObjCConversion)
4218 Sequence.AddObjCObjectConversionStep(cv1T1);
4223 static void CheckCXX98CompatAccessibleCopy(Sema &S,
4224 const InitializedEntity &Entity,
4227 /// \brief Attempt reference initialization (C++0x [dcl.init.ref])
4228 static void TryReferenceInitialization(Sema &S,
4229 const InitializedEntity &Entity,
4230 const InitializationKind &Kind,
4232 InitializationSequence &Sequence) {
4233 QualType DestType = Entity.getType();
4234 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType();
4236 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
4237 QualType cv2T2 = Initializer->getType();
4239 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
4241 // If the initializer is the address of an overloaded function, try
4242 // to resolve the overloaded function. If all goes well, T2 is the
4243 // type of the resulting function.
4244 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
4248 // Delegate everything else to a subfunction.
4249 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
4250 T1Quals, cv2T2, T2, T2Quals, Sequence);
4253 /// Determine whether an expression is a non-referenceable glvalue (one to
4254 /// which a reference can never bind). Attemting to bind a reference to
4255 /// such a glvalue will always create a temporary.
4256 static bool isNonReferenceableGLValue(Expr *E) {
4257 return E->refersToBitField() || E->refersToVectorElement();
4260 /// \brief Reference initialization without resolving overloaded functions.
4261 static void TryReferenceInitializationCore(Sema &S,
4262 const InitializedEntity &Entity,
4263 const InitializationKind &Kind,
4265 QualType cv1T1, QualType T1,
4267 QualType cv2T2, QualType T2,
4269 InitializationSequence &Sequence) {
4270 QualType DestType = Entity.getType();
4271 SourceLocation DeclLoc = Initializer->getLocStart();
4272 // Compute some basic properties of the types and the initializer.
4273 bool isLValueRef = DestType->isLValueReferenceType();
4274 bool isRValueRef = !isLValueRef;
4275 bool DerivedToBase = false;
4276 bool ObjCConversion = false;
4277 bool ObjCLifetimeConversion = false;
4278 Expr::Classification InitCategory = Initializer->Classify(S.Context);
4279 Sema::ReferenceCompareResult RefRelationship
4280 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase,
4281 ObjCConversion, ObjCLifetimeConversion);
4283 // C++0x [dcl.init.ref]p5:
4284 // A reference to type "cv1 T1" is initialized by an expression of type
4285 // "cv2 T2" as follows:
4287 // - If the reference is an lvalue reference and the initializer
4289 // Note the analogous bullet points for rvalue refs to functions. Because
4290 // there are no function rvalues in C++, rvalue refs to functions are treated
4291 // like lvalue refs.
4292 OverloadingResult ConvOvlResult = OR_Success;
4293 bool T1Function = T1->isFunctionType();
4294 if (isLValueRef || T1Function) {
4295 if (InitCategory.isLValue() && !isNonReferenceableGLValue(Initializer) &&
4296 (RefRelationship == Sema::Ref_Compatible ||
4297 (Kind.isCStyleOrFunctionalCast() &&
4298 RefRelationship == Sema::Ref_Related))) {
4299 // - is an lvalue (but is not a bit-field), and "cv1 T1" is
4300 // reference-compatible with "cv2 T2," or
4301 if (T1Quals != T2Quals)
4302 // Convert to cv1 T2. This should only add qualifiers unless this is a
4303 // c-style cast. The removal of qualifiers in that case notionally
4304 // happens after the reference binding, but that doesn't matter.
4305 Sequence.AddQualificationConversionStep(
4306 S.Context.getQualifiedType(T2, T1Quals),
4307 Initializer->getValueKind());
4309 Sequence.AddDerivedToBaseCastStep(cv1T1, VK_LValue);
4310 else if (ObjCConversion)
4311 Sequence.AddObjCObjectConversionStep(cv1T1);
4313 // We only create a temporary here when binding a reference to a
4314 // bit-field or vector element. Those cases are't supposed to be
4315 // handled by this bullet, but the outcome is the same either way.
4316 Sequence.AddReferenceBindingStep(cv1T1, false);
4320 // - has a class type (i.e., T2 is a class type), where T1 is not
4321 // reference-related to T2, and can be implicitly converted to an
4322 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible
4323 // with "cv3 T3" (this conversion is selected by enumerating the
4324 // applicable conversion functions (13.3.1.6) and choosing the best
4325 // one through overload resolution (13.3)),
4326 // If we have an rvalue ref to function type here, the rhs must be
4327 // an rvalue. DR1287 removed the "implicitly" here.
4328 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() &&
4329 (isLValueRef || InitCategory.isRValue())) {
4330 ConvOvlResult = TryRefInitWithConversionFunction(
4331 S, Entity, Kind, Initializer, /*AllowRValues*/ isRValueRef,
4332 /*IsLValueRef*/ isLValueRef, Sequence);
4333 if (ConvOvlResult == OR_Success)
4335 if (ConvOvlResult != OR_No_Viable_Function)
4336 Sequence.SetOverloadFailure(
4337 InitializationSequence::FK_ReferenceInitOverloadFailed,
4342 // - Otherwise, the reference shall be an lvalue reference to a
4343 // non-volatile const type (i.e., cv1 shall be const), or the reference
4344 // shall be an rvalue reference.
4345 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile())) {
4346 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4347 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4348 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4349 Sequence.SetOverloadFailure(
4350 InitializationSequence::FK_ReferenceInitOverloadFailed,
4352 else if (!InitCategory.isLValue())
4354 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
4356 InitializationSequence::FailureKind FK;
4357 switch (RefRelationship) {
4358 case Sema::Ref_Compatible:
4359 if (Initializer->refersToBitField())
4360 FK = InitializationSequence::
4361 FK_NonConstLValueReferenceBindingToBitfield;
4362 else if (Initializer->refersToVectorElement())
4363 FK = InitializationSequence::
4364 FK_NonConstLValueReferenceBindingToVectorElement;
4366 llvm_unreachable("unexpected kind of compatible initializer");
4368 case Sema::Ref_Related:
4369 FK = InitializationSequence::FK_ReferenceInitDropsQualifiers;
4371 case Sema::Ref_Incompatible:
4372 FK = InitializationSequence::
4373 FK_NonConstLValueReferenceBindingToUnrelated;
4376 Sequence.SetFailed(FK);
4381 // - If the initializer expression
4383 // [<=14] xvalue (but not a bit-field), class prvalue, array prvalue, or
4384 // [1z] rvalue (but not a bit-field) or
4385 // function lvalue and "cv1 T1" is reference-compatible with "cv2 T2"
4387 // Note: functions are handled above and below rather than here...
4389 (RefRelationship == Sema::Ref_Compatible ||
4390 (Kind.isCStyleOrFunctionalCast() &&
4391 RefRelationship == Sema::Ref_Related)) &&
4392 ((InitCategory.isXValue() && !isNonReferenceableGLValue(Initializer)) ||
4393 (InitCategory.isPRValue() &&
4394 (S.getLangOpts().CPlusPlus1z || T2->isRecordType() ||
4395 T2->isArrayType())))) {
4396 ExprValueKind ValueKind = InitCategory.isXValue() ? VK_XValue : VK_RValue;
4397 if (InitCategory.isPRValue() && T2->isRecordType()) {
4398 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the
4399 // compiler the freedom to perform a copy here or bind to the
4400 // object, while C++0x requires that we bind directly to the
4401 // object. Hence, we always bind to the object without making an
4402 // extra copy. However, in C++03 requires that we check for the
4403 // presence of a suitable copy constructor:
4405 // The constructor that would be used to make the copy shall
4406 // be callable whether or not the copy is actually done.
4407 if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt)
4408 Sequence.AddExtraneousCopyToTemporary(cv2T2);
4409 else if (S.getLangOpts().CPlusPlus11)
4410 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer);
4413 // C++1z [dcl.init.ref]/5.2.1.2:
4414 // If the converted initializer is a prvalue, its type T4 is adjusted
4415 // to type "cv1 T4" and the temporary materialization conversion is
4417 QualType cv1T4 = S.Context.getQualifiedType(cv2T2, T1Quals);
4418 if (T1Quals != T2Quals)
4419 Sequence.AddQualificationConversionStep(cv1T4, ValueKind);
4420 Sequence.AddReferenceBindingStep(cv1T4, ValueKind == VK_RValue);
4421 ValueKind = isLValueRef ? VK_LValue : VK_XValue;
4423 // In any case, the reference is bound to the resulting glvalue (or to
4424 // an appropriate base class subobject).
4426 Sequence.AddDerivedToBaseCastStep(cv1T1, ValueKind);
4427 else if (ObjCConversion)
4428 Sequence.AddObjCObjectConversionStep(cv1T1);
4432 // - has a class type (i.e., T2 is a class type), where T1 is not
4433 // reference-related to T2, and can be implicitly converted to an
4434 // xvalue, class prvalue, or function lvalue of type "cv3 T3",
4435 // where "cv1 T1" is reference-compatible with "cv3 T3",
4437 // DR1287 removes the "implicitly" here.
4438 if (T2->isRecordType()) {
4439 if (RefRelationship == Sema::Ref_Incompatible) {
4440 ConvOvlResult = TryRefInitWithConversionFunction(
4441 S, Entity, Kind, Initializer, /*AllowRValues*/ true,
4442 /*IsLValueRef*/ isLValueRef, Sequence);
4444 Sequence.SetOverloadFailure(
4445 InitializationSequence::FK_ReferenceInitOverloadFailed,
4451 if (RefRelationship == Sema::Ref_Compatible &&
4452 isRValueRef && InitCategory.isLValue()) {
4454 InitializationSequence::FK_RValueReferenceBindingToLValue);
4458 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
4462 // - Otherwise, a temporary of type "cv1 T1" is created and initialized
4463 // from the initializer expression using the rules for a non-reference
4464 // copy-initialization (8.5). The reference is then bound to the
4467 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1);
4469 // FIXME: Why do we use an implicit conversion here rather than trying
4470 // copy-initialization?
4471 ImplicitConversionSequence ICS
4472 = S.TryImplicitConversion(Initializer, TempEntity.getType(),
4473 /*SuppressUserConversions=*/false,
4474 /*AllowExplicit=*/false,
4475 /*FIXME:InOverloadResolution=*/false,
4476 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
4477 /*AllowObjCWritebackConversion=*/false);
4480 // FIXME: Use the conversion function set stored in ICS to turn
4481 // this into an overloading ambiguity diagnostic. However, we need
4482 // to keep that set as an OverloadCandidateSet rather than as some
4483 // other kind of set.
4484 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4485 Sequence.SetOverloadFailure(
4486 InitializationSequence::FK_ReferenceInitOverloadFailed,
4488 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4489 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4491 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed);
4494 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType());
4497 // [...] If T1 is reference-related to T2, cv1 must be the
4498 // same cv-qualification as, or greater cv-qualification
4499 // than, cv2; otherwise, the program is ill-formed.
4500 unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
4501 unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
4502 if (RefRelationship == Sema::Ref_Related &&
4503 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) {
4504 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
4508 // [...] If T1 is reference-related to T2 and the reference is an rvalue
4509 // reference, the initializer expression shall not be an lvalue.
4510 if (RefRelationship >= Sema::Ref_Related && !isLValueRef &&
4511 InitCategory.isLValue()) {
4513 InitializationSequence::FK_RValueReferenceBindingToLValue);
4517 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true);
4520 /// \brief Attempt character array initialization from a string literal
4521 /// (C++ [dcl.init.string], C99 6.7.8).
4522 static void TryStringLiteralInitialization(Sema &S,
4523 const InitializedEntity &Entity,
4524 const InitializationKind &Kind,
4526 InitializationSequence &Sequence) {
4527 Sequence.AddStringInitStep(Entity.getType());
4530 /// \brief Attempt value initialization (C++ [dcl.init]p7).
4531 static void TryValueInitialization(Sema &S,
4532 const InitializedEntity &Entity,
4533 const InitializationKind &Kind,
4534 InitializationSequence &Sequence,
4535 InitListExpr *InitList) {
4536 assert((!InitList || InitList->getNumInits() == 0) &&
4537 "Shouldn't use value-init for non-empty init lists");
4539 // C++98 [dcl.init]p5, C++11 [dcl.init]p7:
4541 // To value-initialize an object of type T means:
4542 QualType T = Entity.getType();
4544 // -- if T is an array type, then each element is value-initialized;
4545 T = S.Context.getBaseElementType(T);
4547 if (const RecordType *RT = T->getAs<RecordType>()) {
4548 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
4549 bool NeedZeroInitialization = true;
4551 // -- if T is a class type (clause 9) with a user-declared constructor
4552 // (12.1), then the default constructor for T is called (and the
4553 // initialization is ill-formed if T has no accessible default
4556 // -- if T is a class type (clause 9) with either no default constructor
4557 // (12.1 [class.ctor]) or a default constructor that is user-provided
4558 // or deleted, then the object is default-initialized;
4560 // Note that the C++11 rule is the same as the C++98 rule if there are no
4561 // defaulted or deleted constructors, so we just use it unconditionally.
4562 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl);
4563 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted())
4564 NeedZeroInitialization = false;
4566 // -- if T is a (possibly cv-qualified) non-union class type without a
4567 // user-provided or deleted default constructor, then the object is
4568 // zero-initialized and, if T has a non-trivial default constructor,
4569 // default-initialized;
4570 // The 'non-union' here was removed by DR1502. The 'non-trivial default
4571 // constructor' part was removed by DR1507.
4572 if (NeedZeroInitialization)
4573 Sequence.AddZeroInitializationStep(Entity.getType());
4576 // -- if T is a non-union class type without a user-declared constructor,
4577 // then every non-static data member and base class component of T is
4578 // value-initialized;
4579 // [...] A program that calls for [...] value-initialization of an
4580 // entity of reference type is ill-formed.
4582 // C++11 doesn't need this handling, because value-initialization does not
4583 // occur recursively there, and the implicit default constructor is
4584 // defined as deleted in the problematic cases.
4585 if (!S.getLangOpts().CPlusPlus11 &&
4586 ClassDecl->hasUninitializedReferenceMember()) {
4587 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference);
4591 // If this is list-value-initialization, pass the empty init list on when
4592 // building the constructor call. This affects the semantics of a few
4593 // things (such as whether an explicit default constructor can be called).
4594 Expr *InitListAsExpr = InitList;
4595 MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0);
4596 bool InitListSyntax = InitList;
4598 // FIXME: Instead of creating a CXXConstructExpr of array type here,
4599 // wrap a class-typed CXXConstructExpr in an ArrayInitLoopExpr.
4600 return TryConstructorInitialization(
4601 S, Entity, Kind, Args, T, Entity.getType(), Sequence, InitListSyntax);
4605 Sequence.AddZeroInitializationStep(Entity.getType());
4608 /// \brief Attempt default initialization (C++ [dcl.init]p6).
4609 static void TryDefaultInitialization(Sema &S,
4610 const InitializedEntity &Entity,
4611 const InitializationKind &Kind,
4612 InitializationSequence &Sequence) {
4613 assert(Kind.getKind() == InitializationKind::IK_Default);
4615 // C++ [dcl.init]p6:
4616 // To default-initialize an object of type T means:
4617 // - if T is an array type, each element is default-initialized;
4618 QualType DestType = S.Context.getBaseElementType(Entity.getType());
4620 // - if T is a (possibly cv-qualified) class type (Clause 9), the default
4621 // constructor for T is called (and the initialization is ill-formed if
4622 // T has no accessible default constructor);
4623 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) {
4624 TryConstructorInitialization(S, Entity, Kind, None, DestType,
4625 Entity.getType(), Sequence);
4629 // - otherwise, no initialization is performed.
4631 // If a program calls for the default initialization of an object of
4632 // a const-qualified type T, T shall be a class type with a user-provided
4633 // default constructor.
4634 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) {
4635 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
4636 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
4640 // If the destination type has a lifetime property, zero-initialize it.
4641 if (DestType.getQualifiers().hasObjCLifetime()) {
4642 Sequence.AddZeroInitializationStep(Entity.getType());
4647 /// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]),
4648 /// which enumerates all conversion functions and performs overload resolution
4649 /// to select the best.
4650 static void TryUserDefinedConversion(Sema &S,
4652 const InitializationKind &Kind,
4654 InitializationSequence &Sequence,
4655 bool TopLevelOfInitList) {
4656 assert(!DestType->isReferenceType() && "References are handled elsewhere");
4657 QualType SourceType = Initializer->getType();
4658 assert((DestType->isRecordType() || SourceType->isRecordType()) &&
4659 "Must have a class type to perform a user-defined conversion");
4661 // Build the candidate set directly in the initialization sequence
4662 // structure, so that it will persist if we fail.
4663 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4664 CandidateSet.clear();
4666 // Determine whether we are allowed to call explicit constructors or
4667 // explicit conversion operators.
4668 bool AllowExplicit = Kind.AllowExplicit();
4670 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) {
4671 // The type we're converting to is a class type. Enumerate its constructors
4672 // to see if there is a suitable conversion.
4673 CXXRecordDecl *DestRecordDecl
4674 = cast<CXXRecordDecl>(DestRecordType->getDecl());
4676 // Try to complete the type we're converting to.
4677 if (S.isCompleteType(Kind.getLocation(), DestType)) {
4678 DeclContext::lookup_result R = S.LookupConstructors(DestRecordDecl);
4679 // The container holding the constructors can under certain conditions
4680 // be changed while iterating. To be safe we copy the lookup results
4681 // to a new container.
4682 SmallVector<NamedDecl*, 8> CopyOfCon(R.begin(), R.end());
4683 for (SmallVectorImpl<NamedDecl *>::iterator
4684 Con = CopyOfCon.begin(), ConEnd = CopyOfCon.end();
4685 Con != ConEnd; ++Con) {
4686 NamedDecl *D = *Con;
4687 auto Info = getConstructorInfo(D);
4688 if (!Info.Constructor)
4691 if (!Info.Constructor->isInvalidDecl() &&
4692 Info.Constructor->isConvertingConstructor(AllowExplicit)) {
4693 if (Info.ConstructorTmpl)
4694 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
4695 /*ExplicitArgs*/ nullptr,
4696 Initializer, CandidateSet,
4697 /*SuppressUserConversions=*/true);
4699 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
4700 Initializer, CandidateSet,
4701 /*SuppressUserConversions=*/true);
4707 SourceLocation DeclLoc = Initializer->getLocStart();
4709 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) {
4710 // The type we're converting from is a class type, enumerate its conversion
4713 // We can only enumerate the conversion functions for a complete type; if
4714 // the type isn't complete, simply skip this step.
4715 if (S.isCompleteType(DeclLoc, SourceType)) {
4716 CXXRecordDecl *SourceRecordDecl
4717 = cast<CXXRecordDecl>(SourceRecordType->getDecl());
4719 const auto &Conversions =
4720 SourceRecordDecl->getVisibleConversionFunctions();
4721 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4723 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4724 if (isa<UsingShadowDecl>(D))
4725 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4727 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4728 CXXConversionDecl *Conv;
4730 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4732 Conv = cast<CXXConversionDecl>(D);
4734 if (AllowExplicit || !Conv->isExplicit()) {
4736 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(),
4737 ActingDC, Initializer, DestType,
4738 CandidateSet, AllowExplicit);
4740 S.AddConversionCandidate(Conv, I.getPair(), ActingDC,
4741 Initializer, DestType, CandidateSet,
4748 // Perform overload resolution. If it fails, return the failed result.
4749 OverloadCandidateSet::iterator Best;
4750 if (OverloadingResult Result
4751 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) {
4752 Sequence.SetOverloadFailure(
4753 InitializationSequence::FK_UserConversionOverloadFailed,
4758 FunctionDecl *Function = Best->Function;
4759 Function->setReferenced();
4760 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4762 if (isa<CXXConstructorDecl>(Function)) {
4763 // Add the user-defined conversion step. Any cv-qualification conversion is
4764 // subsumed by the initialization. Per DR5, the created temporary is of the
4765 // cv-unqualified type of the destination.
4766 Sequence.AddUserConversionStep(Function, Best->FoundDecl,
4767 DestType.getUnqualifiedType(),
4768 HadMultipleCandidates);
4770 // C++14 and before:
4771 // - if the function is a constructor, the call initializes a temporary
4772 // of the cv-unqualified version of the destination type. The [...]
4773 // temporary [...] is then used to direct-initialize, according to the
4774 // rules above, the object that is the destination of the
4775 // copy-initialization.
4776 // Note that this just performs a simple object copy from the temporary.
4779 // - if the function is a constructor, the call is a prvalue of the
4780 // cv-unqualified version of the destination type whose return object
4781 // is initialized by the constructor. The call is used to
4782 // direct-initialize, according to the rules above, the object that
4783 // is the destination of the copy-initialization.
4784 // Therefore we need to do nothing further.
4786 // FIXME: Mark this copy as extraneous.
4787 if (!S.getLangOpts().CPlusPlus1z)
4788 Sequence.AddFinalCopy(DestType);
4789 else if (DestType.hasQualifiers())
4790 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
4794 // Add the user-defined conversion step that calls the conversion function.
4795 QualType ConvType = Function->getCallResultType();
4796 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType,
4797 HadMultipleCandidates);
4799 if (ConvType->getAs<RecordType>()) {
4800 // The call is used to direct-initialize [...] the object that is the
4801 // destination of the copy-initialization.
4803 // In C++1z, this does not call a constructor if we enter /17.6.1:
4804 // - If the initializer expression is a prvalue and the cv-unqualified
4805 // version of the source type is the same as the class of the
4806 // destination [... do not make an extra copy]
4808 // FIXME: Mark this copy as extraneous.
4809 if (!S.getLangOpts().CPlusPlus1z ||
4810 Function->getReturnType()->isReferenceType() ||
4811 !S.Context.hasSameUnqualifiedType(ConvType, DestType))
4812 Sequence.AddFinalCopy(DestType);
4813 else if (!S.Context.hasSameType(ConvType, DestType))
4814 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
4818 // If the conversion following the call to the conversion function
4819 // is interesting, add it as a separate step.
4820 if (Best->FinalConversion.First || Best->FinalConversion.Second ||
4821 Best->FinalConversion.Third) {
4822 ImplicitConversionSequence ICS;
4824 ICS.Standard = Best->FinalConversion;
4825 Sequence.AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
4829 /// An egregious hack for compatibility with libstdc++-4.2: in <tr1/hashtable>,
4830 /// a function with a pointer return type contains a 'return false;' statement.
4831 /// In C++11, 'false' is not a null pointer, so this breaks the build of any
4832 /// code using that header.
4834 /// Work around this by treating 'return false;' as zero-initializing the result
4835 /// if it's used in a pointer-returning function in a system header.
4836 static bool isLibstdcxxPointerReturnFalseHack(Sema &S,
4837 const InitializedEntity &Entity,
4839 return S.getLangOpts().CPlusPlus11 &&
4840 Entity.getKind() == InitializedEntity::EK_Result &&
4841 Entity.getType()->isPointerType() &&
4842 isa<CXXBoolLiteralExpr>(Init) &&
4843 !cast<CXXBoolLiteralExpr>(Init)->getValue() &&
4844 S.getSourceManager().isInSystemHeader(Init->getExprLoc());
4847 /// The non-zero enum values here are indexes into diagnostic alternatives.
4848 enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar };
4850 /// Determines whether this expression is an acceptable ICR source.
4851 static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e,
4852 bool isAddressOf, bool &isWeakAccess) {
4854 e = e->IgnoreParens();
4856 // Skip address-of nodes.
4857 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
4858 if (op->getOpcode() == UO_AddrOf)
4859 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true,
4862 // Skip certain casts.
4863 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) {
4864 switch (ce->getCastKind()) {
4867 case CK_LValueBitCast:
4869 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess);
4871 case CK_ArrayToPointerDecay:
4872 return IIK_nonscalar;
4874 case CK_NullToPointer:
4881 // If we have a declaration reference, it had better be a local variable.
4882 } else if (isa<DeclRefExpr>(e)) {
4883 // set isWeakAccess to true, to mean that there will be an implicit
4884 // load which requires a cleanup.
4885 if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
4886 isWeakAccess = true;
4888 if (!isAddressOf) return IIK_nonlocal;
4890 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl());
4891 if (!var) return IIK_nonlocal;
4893 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal);
4895 // If we have a conditional operator, check both sides.
4896 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) {
4897 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf,
4901 return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess);
4903 // These are never scalar.
4904 } else if (isa<ArraySubscriptExpr>(e)) {
4905 return IIK_nonscalar;
4907 // Otherwise, it needs to be a null pointer constant.
4909 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull)
4910 ? IIK_okay : IIK_nonlocal);
4913 return IIK_nonlocal;
4916 /// Check whether the given expression is a valid operand for an
4917 /// indirect copy/restore.
4918 static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) {
4919 assert(src->isRValue());
4920 bool isWeakAccess = false;
4921 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess);
4922 // If isWeakAccess to true, there will be an implicit
4923 // load which requires a cleanup.
4924 if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess)
4925 S.Cleanup.setExprNeedsCleanups(true);
4927 if (iik == IIK_okay) return;
4929 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback)
4930 << ((unsigned) iik - 1) // shift index into diagnostic explanations
4931 << src->getSourceRange();
4934 /// \brief Determine whether we have compatible array types for the
4935 /// purposes of GNU by-copy array initialization.
4936 static bool hasCompatibleArrayTypes(ASTContext &Context, const ArrayType *Dest,
4937 const ArrayType *Source) {
4938 // If the source and destination array types are equivalent, we're
4940 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0)))
4943 // Make sure that the element types are the same.
4944 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType()))
4947 // The only mismatch we allow is when the destination is an
4948 // incomplete array type and the source is a constant array type.
4949 return Source->isConstantArrayType() && Dest->isIncompleteArrayType();
4952 static bool tryObjCWritebackConversion(Sema &S,
4953 InitializationSequence &Sequence,
4954 const InitializedEntity &Entity,
4955 Expr *Initializer) {
4956 bool ArrayDecay = false;
4957 QualType ArgType = Initializer->getType();
4958 QualType ArgPointee;
4959 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) {
4961 ArgPointee = ArgArrayType->getElementType();
4962 ArgType = S.Context.getPointerType(ArgPointee);
4965 // Handle write-back conversion.
4966 QualType ConvertedArgType;
4967 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(),
4971 // We should copy unless we're passing to an argument explicitly
4973 bool ShouldCopy = true;
4974 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
4975 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
4977 // Do we need an lvalue conversion?
4978 if (ArrayDecay || Initializer->isGLValue()) {
4979 ImplicitConversionSequence ICS;
4981 ICS.Standard.setAsIdentityConversion();
4983 QualType ResultType;
4985 ICS.Standard.First = ICK_Array_To_Pointer;
4986 ResultType = S.Context.getPointerType(ArgPointee);
4988 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
4989 ResultType = Initializer->getType().getNonLValueExprType(S.Context);
4992 Sequence.AddConversionSequenceStep(ICS, ResultType);
4995 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy);
4999 static bool TryOCLSamplerInitialization(Sema &S,
5000 InitializationSequence &Sequence,
5002 Expr *Initializer) {
5003 if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() ||
5004 (!Initializer->isIntegerConstantExpr(S.Context) &&
5005 !Initializer->getType()->isSamplerT()))
5008 Sequence.AddOCLSamplerInitStep(DestType);
5013 // OpenCL 1.2 spec, s6.12.10
5015 // The event argument can also be used to associate the
5016 // async_work_group_copy with a previous async copy allowing
5017 // an event to be shared by multiple async copies; otherwise
5018 // event should be zero.
5020 static bool TryOCLZeroEventInitialization(Sema &S,
5021 InitializationSequence &Sequence,
5023 Expr *Initializer) {
5024 if (!S.getLangOpts().OpenCL || !DestType->isEventT() ||
5025 !Initializer->isIntegerConstantExpr(S.getASTContext()) ||
5026 (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0))
5029 Sequence.AddOCLZeroEventStep(DestType);
5033 static bool TryOCLZeroQueueInitialization(Sema &S,
5034 InitializationSequence &Sequence,
5036 Expr *Initializer) {
5037 if (!S.getLangOpts().OpenCL || S.getLangOpts().OpenCLVersion < 200 ||
5038 !DestType->isQueueT() ||
5039 !Initializer->isIntegerConstantExpr(S.getASTContext()) ||
5040 (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0))
5043 Sequence.AddOCLZeroQueueStep(DestType);
5047 InitializationSequence::InitializationSequence(Sema &S,
5048 const InitializedEntity &Entity,
5049 const InitializationKind &Kind,
5051 bool TopLevelOfInitList,
5052 bool TreatUnavailableAsInvalid)
5053 : FailedCandidateSet(Kind.getLocation(), OverloadCandidateSet::CSK_Normal) {
5054 InitializeFrom(S, Entity, Kind, Args, TopLevelOfInitList,
5055 TreatUnavailableAsInvalid);
5058 /// Tries to get a FunctionDecl out of `E`. If it succeeds and we can take the
5059 /// address of that function, this returns true. Otherwise, it returns false.
5060 static bool isExprAnUnaddressableFunction(Sema &S, const Expr *E) {
5061 auto *DRE = dyn_cast<DeclRefExpr>(E);
5062 if (!DRE || !isa<FunctionDecl>(DRE->getDecl()))
5065 return !S.checkAddressOfFunctionIsAvailable(
5066 cast<FunctionDecl>(DRE->getDecl()));
5069 /// Determine whether we can perform an elementwise array copy for this kind
5071 static bool canPerformArrayCopy(const InitializedEntity &Entity) {
5072 switch (Entity.getKind()) {
5073 case InitializedEntity::EK_LambdaCapture:
5074 // C++ [expr.prim.lambda]p24:
5075 // For array members, the array elements are direct-initialized in
5076 // increasing subscript order.
5079 case InitializedEntity::EK_Variable:
5080 // C++ [dcl.decomp]p1:
5081 // [...] each element is copy-initialized or direct-initialized from the
5082 // corresponding element of the assignment-expression [...]
5083 return isa<DecompositionDecl>(Entity.getDecl());
5085 case InitializedEntity::EK_Member:
5086 // C++ [class.copy.ctor]p14:
5087 // - if the member is an array, each element is direct-initialized with
5088 // the corresponding subobject of x
5089 return Entity.isImplicitMemberInitializer();
5091 case InitializedEntity::EK_ArrayElement:
5092 // All the above cases are intended to apply recursively, even though none
5093 // of them actually say that.
5094 if (auto *E = Entity.getParent())
5095 return canPerformArrayCopy(*E);
5105 void InitializationSequence::InitializeFrom(Sema &S,
5106 const InitializedEntity &Entity,
5107 const InitializationKind &Kind,
5109 bool TopLevelOfInitList,
5110 bool TreatUnavailableAsInvalid) {
5111 ASTContext &Context = S.Context;
5113 // Eliminate non-overload placeholder types in the arguments. We
5114 // need to do this before checking whether types are dependent
5115 // because lowering a pseudo-object expression might well give us
5116 // something of dependent type.
5117 for (unsigned I = 0, E = Args.size(); I != E; ++I)
5118 if (Args[I]->getType()->isNonOverloadPlaceholderType()) {
5119 // FIXME: should we be doing this here?
5120 ExprResult result = S.CheckPlaceholderExpr(Args[I]);
5121 if (result.isInvalid()) {
5122 SetFailed(FK_PlaceholderType);
5125 Args[I] = result.get();
5128 // C++0x [dcl.init]p16:
5129 // The semantics of initializers are as follows. The destination type is
5130 // the type of the object or reference being initialized and the source
5131 // type is the type of the initializer expression. The source type is not
5132 // defined when the initializer is a braced-init-list or when it is a
5133 // parenthesized list of expressions.
5134 QualType DestType = Entity.getType();
5136 if (DestType->isDependentType() ||
5137 Expr::hasAnyTypeDependentArguments(Args)) {
5138 SequenceKind = DependentSequence;
5142 // Almost everything is a normal sequence.
5143 setSequenceKind(NormalSequence);
5145 QualType SourceType;
5146 Expr *Initializer = nullptr;
5147 if (Args.size() == 1) {
5148 Initializer = Args[0];
5149 if (S.getLangOpts().ObjC1) {
5150 if (S.CheckObjCBridgeRelatedConversions(Initializer->getLocStart(),
5151 DestType, Initializer->getType(),
5153 S.ConversionToObjCStringLiteralCheck(DestType, Initializer))
5154 Args[0] = Initializer;
5156 if (!isa<InitListExpr>(Initializer))
5157 SourceType = Initializer->getType();
5160 // - If the initializer is a (non-parenthesized) braced-init-list, the
5161 // object is list-initialized (8.5.4).
5162 if (Kind.getKind() != InitializationKind::IK_Direct) {
5163 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) {
5164 TryListInitialization(S, Entity, Kind, InitList, *this,
5165 TreatUnavailableAsInvalid);
5170 // - If the destination type is a reference type, see 8.5.3.
5171 if (DestType->isReferenceType()) {
5172 // C++0x [dcl.init.ref]p1:
5173 // A variable declared to be a T& or T&&, that is, "reference to type T"
5174 // (8.3.2), shall be initialized by an object, or function, of type T or
5175 // by an object that can be converted into a T.
5176 // (Therefore, multiple arguments are not permitted.)
5177 if (Args.size() != 1)
5178 SetFailed(FK_TooManyInitsForReference);
5180 TryReferenceInitialization(S, Entity, Kind, Args[0], *this);
5184 // - If the initializer is (), the object is value-initialized.
5185 if (Kind.getKind() == InitializationKind::IK_Value ||
5186 (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) {
5187 TryValueInitialization(S, Entity, Kind, *this);
5191 // Handle default initialization.
5192 if (Kind.getKind() == InitializationKind::IK_Default) {
5193 TryDefaultInitialization(S, Entity, Kind, *this);
5197 // - If the destination type is an array of characters, an array of
5198 // char16_t, an array of char32_t, or an array of wchar_t, and the
5199 // initializer is a string literal, see 8.5.2.
5200 // - Otherwise, if the destination type is an array, the program is
5202 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) {
5203 if (Initializer && isa<VariableArrayType>(DestAT)) {
5204 SetFailed(FK_VariableLengthArrayHasInitializer);
5209 switch (IsStringInit(Initializer, DestAT, Context)) {
5211 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this);
5213 case SIF_NarrowStringIntoWideChar:
5214 SetFailed(FK_NarrowStringIntoWideCharArray);
5216 case SIF_WideStringIntoChar:
5217 SetFailed(FK_WideStringIntoCharArray);
5219 case SIF_IncompatWideStringIntoWideChar:
5220 SetFailed(FK_IncompatWideStringIntoWideChar);
5227 // Some kinds of initialization permit an array to be initialized from
5228 // another array of the same type, and perform elementwise initialization.
5229 if (Initializer && isa<ConstantArrayType>(DestAT) &&
5230 S.Context.hasSameUnqualifiedType(Initializer->getType(),
5231 Entity.getType()) &&
5232 canPerformArrayCopy(Entity)) {
5233 // If source is a prvalue, use it directly.
5234 if (Initializer->getValueKind() == VK_RValue) {
5235 AddArrayInitStep(DestType, /*IsGNUExtension*/false);
5239 // Emit element-at-a-time copy loop.
5240 InitializedEntity Element =
5241 InitializedEntity::InitializeElement(S.Context, 0, Entity);
5243 Context.getAsArrayType(Initializer->getType())->getElementType();
5244 OpaqueValueExpr OVE(Initializer->getExprLoc(), InitEltT,
5245 Initializer->getValueKind(),
5246 Initializer->getObjectKind());
5247 Expr *OVEAsExpr = &OVE;
5248 InitializeFrom(S, Element, Kind, OVEAsExpr, TopLevelOfInitList,
5249 TreatUnavailableAsInvalid);
5251 AddArrayInitLoopStep(Entity.getType(), InitEltT);
5255 // Note: as an GNU C extension, we allow initialization of an
5256 // array from a compound literal that creates an array of the same
5257 // type, so long as the initializer has no side effects.
5258 if (!S.getLangOpts().CPlusPlus && Initializer &&
5259 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) &&
5260 Initializer->getType()->isArrayType()) {
5261 const ArrayType *SourceAT
5262 = Context.getAsArrayType(Initializer->getType());
5263 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT))
5264 SetFailed(FK_ArrayTypeMismatch);
5265 else if (Initializer->HasSideEffects(S.Context))
5266 SetFailed(FK_NonConstantArrayInit);
5268 AddArrayInitStep(DestType, /*IsGNUExtension*/true);
5271 // Note: as a GNU C++ extension, we allow list-initialization of a
5272 // class member of array type from a parenthesized initializer list.
5273 else if (S.getLangOpts().CPlusPlus &&
5274 Entity.getKind() == InitializedEntity::EK_Member &&
5275 Initializer && isa<InitListExpr>(Initializer)) {
5276 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer),
5277 *this, TreatUnavailableAsInvalid);
5278 AddParenthesizedArrayInitStep(DestType);
5279 } else if (DestAT->getElementType()->isCharType())
5280 SetFailed(FK_ArrayNeedsInitListOrStringLiteral);
5281 else if (IsWideCharCompatible(DestAT->getElementType(), Context))
5282 SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral);
5284 SetFailed(FK_ArrayNeedsInitList);
5289 // Determine whether we should consider writeback conversions for
5291 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount &&
5292 Entity.isParameterKind();
5294 // We're at the end of the line for C: it's either a write-back conversion
5295 // or it's a C assignment. There's no need to check anything else.
5296 if (!S.getLangOpts().CPlusPlus) {
5297 // If allowed, check whether this is an Objective-C writeback conversion.
5298 if (allowObjCWritebackConversion &&
5299 tryObjCWritebackConversion(S, *this, Entity, Initializer)) {
5303 if (TryOCLSamplerInitialization(S, *this, DestType, Initializer))
5306 if (TryOCLZeroEventInitialization(S, *this, DestType, Initializer))
5309 if (TryOCLZeroQueueInitialization(S, *this, DestType, Initializer))
5312 // Handle initialization in C
5313 AddCAssignmentStep(DestType);
5314 MaybeProduceObjCObject(S, *this, Entity);
5318 assert(S.getLangOpts().CPlusPlus);
5320 // - If the destination type is a (possibly cv-qualified) class type:
5321 if (DestType->isRecordType()) {
5322 // - If the initialization is direct-initialization, or if it is
5323 // copy-initialization where the cv-unqualified version of the
5324 // source type is the same class as, or a derived class of, the
5325 // class of the destination, constructors are considered. [...]
5326 if (Kind.getKind() == InitializationKind::IK_Direct ||
5327 (Kind.getKind() == InitializationKind::IK_Copy &&
5328 (Context.hasSameUnqualifiedType(SourceType, DestType) ||
5329 S.IsDerivedFrom(Initializer->getLocStart(), SourceType, DestType))))
5330 TryConstructorInitialization(S, Entity, Kind, Args,
5331 DestType, DestType, *this);
5332 // - Otherwise (i.e., for the remaining copy-initialization cases),
5333 // user-defined conversion sequences that can convert from the source
5334 // type to the destination type or (when a conversion function is
5335 // used) to a derived class thereof are enumerated as described in
5336 // 13.3.1.4, and the best one is chosen through overload resolution
5339 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5340 TopLevelOfInitList);
5344 if (Args.size() > 1) {
5345 SetFailed(FK_TooManyInitsForScalar);
5348 assert(Args.size() == 1 && "Zero-argument case handled above");
5350 // - Otherwise, if the source type is a (possibly cv-qualified) class
5351 // type, conversion functions are considered.
5352 if (!SourceType.isNull() && SourceType->isRecordType()) {
5353 // For a conversion to _Atomic(T) from either T or a class type derived
5354 // from T, initialize the T object then convert to _Atomic type.
5355 bool NeedAtomicConversion = false;
5356 if (const AtomicType *Atomic = DestType->getAs<AtomicType>()) {
5357 if (Context.hasSameUnqualifiedType(SourceType, Atomic->getValueType()) ||
5358 S.IsDerivedFrom(Initializer->getLocStart(), SourceType,
5359 Atomic->getValueType())) {
5360 DestType = Atomic->getValueType();
5361 NeedAtomicConversion = true;
5365 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5366 TopLevelOfInitList);
5367 MaybeProduceObjCObject(S, *this, Entity);
5368 if (!Failed() && NeedAtomicConversion)
5369 AddAtomicConversionStep(Entity.getType());
5373 // - Otherwise, the initial value of the object being initialized is the
5374 // (possibly converted) value of the initializer expression. Standard
5375 // conversions (Clause 4) will be used, if necessary, to convert the
5376 // initializer expression to the cv-unqualified version of the
5377 // destination type; no user-defined conversions are considered.
5379 ImplicitConversionSequence ICS
5380 = S.TryImplicitConversion(Initializer, DestType,
5381 /*SuppressUserConversions*/true,
5382 /*AllowExplicitConversions*/ false,
5383 /*InOverloadResolution*/ false,
5384 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
5385 allowObjCWritebackConversion);
5387 if (ICS.isStandard() &&
5388 ICS.Standard.Second == ICK_Writeback_Conversion) {
5389 // Objective-C ARC writeback conversion.
5391 // We should copy unless we're passing to an argument explicitly
5393 bool ShouldCopy = true;
5394 if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
5395 ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
5397 // If there was an lvalue adjustment, add it as a separate conversion.
5398 if (ICS.Standard.First == ICK_Array_To_Pointer ||
5399 ICS.Standard.First == ICK_Lvalue_To_Rvalue) {
5400 ImplicitConversionSequence LvalueICS;
5401 LvalueICS.setStandard();
5402 LvalueICS.Standard.setAsIdentityConversion();
5403 LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0));
5404 LvalueICS.Standard.First = ICS.Standard.First;
5405 AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0));
5408 AddPassByIndirectCopyRestoreStep(DestType, ShouldCopy);
5409 } else if (ICS.isBad()) {
5411 if (isLibstdcxxPointerReturnFalseHack(S, Entity, Initializer)) {
5412 AddZeroInitializationStep(Entity.getType());
5413 } else if (Initializer->getType() == Context.OverloadTy &&
5414 !S.ResolveAddressOfOverloadedFunction(Initializer, DestType,
5416 SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
5417 else if (Initializer->getType()->isFunctionType() &&
5418 isExprAnUnaddressableFunction(S, Initializer))
5419 SetFailed(InitializationSequence::FK_AddressOfUnaddressableFunction);
5421 SetFailed(InitializationSequence::FK_ConversionFailed);
5423 AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
5425 MaybeProduceObjCObject(S, *this, Entity);
5429 InitializationSequence::~InitializationSequence() {
5430 for (auto &S : Steps)
5434 //===----------------------------------------------------------------------===//
5435 // Perform initialization
5436 //===----------------------------------------------------------------------===//
5437 static Sema::AssignmentAction
5438 getAssignmentAction(const InitializedEntity &Entity, bool Diagnose = false) {
5439 switch(Entity.getKind()) {
5440 case InitializedEntity::EK_Variable:
5441 case InitializedEntity::EK_New:
5442 case InitializedEntity::EK_Exception:
5443 case InitializedEntity::EK_Base:
5444 case InitializedEntity::EK_Delegating:
5445 return Sema::AA_Initializing;
5447 case InitializedEntity::EK_Parameter:
5448 if (Entity.getDecl() &&
5449 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
5450 return Sema::AA_Sending;
5452 return Sema::AA_Passing;
5454 case InitializedEntity::EK_Parameter_CF_Audited:
5455 if (Entity.getDecl() &&
5456 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext()))
5457 return Sema::AA_Sending;
5459 return !Diagnose ? Sema::AA_Passing : Sema::AA_Passing_CFAudited;
5461 case InitializedEntity::EK_Result:
5462 return Sema::AA_Returning;
5464 case InitializedEntity::EK_Temporary:
5465 case InitializedEntity::EK_RelatedResult:
5466 // FIXME: Can we tell apart casting vs. converting?
5467 return Sema::AA_Casting;
5469 case InitializedEntity::EK_Member:
5470 case InitializedEntity::EK_Binding:
5471 case InitializedEntity::EK_ArrayElement:
5472 case InitializedEntity::EK_VectorElement:
5473 case InitializedEntity::EK_ComplexElement:
5474 case InitializedEntity::EK_BlockElement:
5475 case InitializedEntity::EK_LambdaCapture:
5476 case InitializedEntity::EK_CompoundLiteralInit:
5477 return Sema::AA_Initializing;
5480 llvm_unreachable("Invalid EntityKind!");
5483 /// \brief Whether we should bind a created object as a temporary when
5484 /// initializing the given entity.
5485 static bool shouldBindAsTemporary(const InitializedEntity &Entity) {
5486 switch (Entity.getKind()) {
5487 case InitializedEntity::EK_ArrayElement:
5488 case InitializedEntity::EK_Member:
5489 case InitializedEntity::EK_Result:
5490 case InitializedEntity::EK_New:
5491 case InitializedEntity::EK_Variable:
5492 case InitializedEntity::EK_Base:
5493 case InitializedEntity::EK_Delegating:
5494 case InitializedEntity::EK_VectorElement:
5495 case InitializedEntity::EK_ComplexElement:
5496 case InitializedEntity::EK_Exception:
5497 case InitializedEntity::EK_BlockElement:
5498 case InitializedEntity::EK_LambdaCapture:
5499 case InitializedEntity::EK_CompoundLiteralInit:
5502 case InitializedEntity::EK_Parameter:
5503 case InitializedEntity::EK_Parameter_CF_Audited:
5504 case InitializedEntity::EK_Temporary:
5505 case InitializedEntity::EK_RelatedResult:
5506 case InitializedEntity::EK_Binding:
5510 llvm_unreachable("missed an InitializedEntity kind?");
5513 /// \brief Whether the given entity, when initialized with an object
5514 /// created for that initialization, requires destruction.
5515 static bool shouldDestroyEntity(const InitializedEntity &Entity) {
5516 switch (Entity.getKind()) {
5517 case InitializedEntity::EK_Result:
5518 case InitializedEntity::EK_New:
5519 case InitializedEntity::EK_Base:
5520 case InitializedEntity::EK_Delegating:
5521 case InitializedEntity::EK_VectorElement:
5522 case InitializedEntity::EK_ComplexElement:
5523 case InitializedEntity::EK_BlockElement:
5524 case InitializedEntity::EK_LambdaCapture:
5527 case InitializedEntity::EK_Member:
5528 case InitializedEntity::EK_Binding:
5529 case InitializedEntity::EK_Variable:
5530 case InitializedEntity::EK_Parameter:
5531 case InitializedEntity::EK_Parameter_CF_Audited:
5532 case InitializedEntity::EK_Temporary:
5533 case InitializedEntity::EK_ArrayElement:
5534 case InitializedEntity::EK_Exception:
5535 case InitializedEntity::EK_CompoundLiteralInit:
5536 case InitializedEntity::EK_RelatedResult:
5540 llvm_unreachable("missed an InitializedEntity kind?");
5543 /// \brief Get the location at which initialization diagnostics should appear.
5544 static SourceLocation getInitializationLoc(const InitializedEntity &Entity,
5545 Expr *Initializer) {
5546 switch (Entity.getKind()) {
5547 case InitializedEntity::EK_Result:
5548 return Entity.getReturnLoc();
5550 case InitializedEntity::EK_Exception:
5551 return Entity.getThrowLoc();
5553 case InitializedEntity::EK_Variable:
5554 case InitializedEntity::EK_Binding:
5555 return Entity.getDecl()->getLocation();
5557 case InitializedEntity::EK_LambdaCapture:
5558 return Entity.getCaptureLoc();
5560 case InitializedEntity::EK_ArrayElement:
5561 case InitializedEntity::EK_Member:
5562 case InitializedEntity::EK_Parameter:
5563 case InitializedEntity::EK_Parameter_CF_Audited:
5564 case InitializedEntity::EK_Temporary:
5565 case InitializedEntity::EK_New:
5566 case InitializedEntity::EK_Base:
5567 case InitializedEntity::EK_Delegating:
5568 case InitializedEntity::EK_VectorElement:
5569 case InitializedEntity::EK_ComplexElement:
5570 case InitializedEntity::EK_BlockElement:
5571 case InitializedEntity::EK_CompoundLiteralInit:
5572 case InitializedEntity::EK_RelatedResult:
5573 return Initializer->getLocStart();
5575 llvm_unreachable("missed an InitializedEntity kind?");
5578 /// \brief Make a (potentially elidable) temporary copy of the object
5579 /// provided by the given initializer by calling the appropriate copy
5582 /// \param S The Sema object used for type-checking.
5584 /// \param T The type of the temporary object, which must either be
5585 /// the type of the initializer expression or a superclass thereof.
5587 /// \param Entity The entity being initialized.
5589 /// \param CurInit The initializer expression.
5591 /// \param IsExtraneousCopy Whether this is an "extraneous" copy that
5592 /// is permitted in C++03 (but not C++0x) when binding a reference to
5595 /// \returns An expression that copies the initializer expression into
5596 /// a temporary object, or an error expression if a copy could not be
5598 static ExprResult CopyObject(Sema &S,
5600 const InitializedEntity &Entity,
5602 bool IsExtraneousCopy) {
5603 if (CurInit.isInvalid())
5605 // Determine which class type we're copying to.
5606 Expr *CurInitExpr = (Expr *)CurInit.get();
5607 CXXRecordDecl *Class = nullptr;
5608 if (const RecordType *Record = T->getAs<RecordType>())
5609 Class = cast<CXXRecordDecl>(Record->getDecl());
5613 SourceLocation Loc = getInitializationLoc(Entity, CurInit.get());
5615 // Make sure that the type we are copying is complete.
5616 if (S.RequireCompleteType(Loc, T, diag::err_temp_copy_incomplete))
5619 // Perform overload resolution using the class's constructors. Per
5620 // C++11 [dcl.init]p16, second bullet for class types, this initialization
5621 // is direct-initialization.
5622 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5623 DeclContext::lookup_result Ctors = S.LookupConstructors(Class);
5625 OverloadCandidateSet::iterator Best;
5626 switch (ResolveConstructorOverload(
5627 S, Loc, CurInitExpr, CandidateSet, Ctors, Best,
5628 /*CopyInitializing=*/false, /*AllowExplicit=*/true,
5629 /*OnlyListConstructors=*/false, /*IsListInit=*/false,
5630 /*SecondStepOfCopyInit=*/true)) {
5634 case OR_No_Viable_Function:
5635 S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext()
5636 ? diag::ext_rvalue_to_reference_temp_copy_no_viable
5637 : diag::err_temp_copy_no_viable)
5638 << (int)Entity.getKind() << CurInitExpr->getType()
5639 << CurInitExpr->getSourceRange();
5640 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr);
5641 if (!IsExtraneousCopy || S.isSFINAEContext())
5646 S.Diag(Loc, diag::err_temp_copy_ambiguous)
5647 << (int)Entity.getKind() << CurInitExpr->getType()
5648 << CurInitExpr->getSourceRange();
5649 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr);
5653 S.Diag(Loc, diag::err_temp_copy_deleted)
5654 << (int)Entity.getKind() << CurInitExpr->getType()
5655 << CurInitExpr->getSourceRange();
5656 S.NoteDeletedFunction(Best->Function);
5660 bool HadMultipleCandidates = CandidateSet.size() > 1;
5662 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function);
5663 SmallVector<Expr*, 8> ConstructorArgs;
5664 CurInit.get(); // Ownership transferred into MultiExprArg, below.
5666 S.CheckConstructorAccess(Loc, Constructor, Best->FoundDecl, Entity,
5669 if (IsExtraneousCopy) {
5670 // If this is a totally extraneous copy for C++03 reference
5671 // binding purposes, just return the original initialization
5672 // expression. We don't generate an (elided) copy operation here
5673 // because doing so would require us to pass down a flag to avoid
5674 // infinite recursion, where each step adds another extraneous,
5677 // Instantiate the default arguments of any extra parameters in
5678 // the selected copy constructor, as if we were going to create a
5679 // proper call to the copy constructor.
5680 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) {
5681 ParmVarDecl *Parm = Constructor->getParamDecl(I);
5682 if (S.RequireCompleteType(Loc, Parm->getType(),
5683 diag::err_call_incomplete_argument))
5686 // Build the default argument expression; we don't actually care
5687 // if this succeeds or not, because this routine will complain
5688 // if there was a problem.
5689 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm);
5695 // Determine the arguments required to actually perform the
5696 // constructor call (we might have derived-to-base conversions, or
5697 // the copy constructor may have default arguments).
5698 if (S.CompleteConstructorCall(Constructor, CurInitExpr, Loc, ConstructorArgs))
5701 // C++0x [class.copy]p32:
5702 // When certain criteria are met, an implementation is allowed to
5703 // omit the copy/move construction of a class object, even if the
5704 // copy/move constructor and/or destructor for the object have
5705 // side effects. [...]
5706 // - when a temporary class object that has not been bound to a
5707 // reference (12.2) would be copied/moved to a class object
5708 // with the same cv-unqualified type, the copy/move operation
5709 // can be omitted by constructing the temporary object
5710 // directly into the target of the omitted copy/move
5712 // Note that the other three bullets are handled elsewhere. Copy
5713 // elision for return statements and throw expressions are handled as part
5714 // of constructor initialization, while copy elision for exception handlers
5715 // is handled by the run-time.
5717 // FIXME: If the function parameter is not the same type as the temporary, we
5718 // should still be able to elide the copy, but we don't have a way to
5719 // represent in the AST how much should be elided in this case.
5721 CurInitExpr->isTemporaryObject(S.Context, Class) &&
5722 S.Context.hasSameUnqualifiedType(
5723 Best->Function->getParamDecl(0)->getType().getNonReferenceType(),
5724 CurInitExpr->getType());
5726 // Actually perform the constructor call.
5727 CurInit = S.BuildCXXConstructExpr(Loc, T, Best->FoundDecl, Constructor,
5730 HadMultipleCandidates,
5732 /*StdInitListInit*/ false,
5734 CXXConstructExpr::CK_Complete,
5737 // If we're supposed to bind temporaries, do so.
5738 if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity))
5739 CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
5743 /// \brief Check whether elidable copy construction for binding a reference to
5744 /// a temporary would have succeeded if we were building in C++98 mode, for
5746 static void CheckCXX98CompatAccessibleCopy(Sema &S,
5747 const InitializedEntity &Entity,
5748 Expr *CurInitExpr) {
5749 assert(S.getLangOpts().CPlusPlus11);
5751 const RecordType *Record = CurInitExpr->getType()->getAs<RecordType>();
5755 SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr);
5756 if (S.Diags.isIgnored(diag::warn_cxx98_compat_temp_copy, Loc))
5759 // Find constructors which would have been considered.
5760 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5761 DeclContext::lookup_result Ctors =
5762 S.LookupConstructors(cast<CXXRecordDecl>(Record->getDecl()));
5764 // Perform overload resolution.
5765 OverloadCandidateSet::iterator Best;
5766 OverloadingResult OR = ResolveConstructorOverload(
5767 S, Loc, CurInitExpr, CandidateSet, Ctors, Best,
5768 /*CopyInitializing=*/false, /*AllowExplicit=*/true,
5769 /*OnlyListConstructors=*/false, /*IsListInit=*/false,
5770 /*SecondStepOfCopyInit=*/true);
5772 PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy)
5773 << OR << (int)Entity.getKind() << CurInitExpr->getType()
5774 << CurInitExpr->getSourceRange();
5778 S.CheckConstructorAccess(Loc, cast<CXXConstructorDecl>(Best->Function),
5779 Best->FoundDecl, Entity, Diag);
5780 // FIXME: Check default arguments as far as that's possible.
5783 case OR_No_Viable_Function:
5785 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr);
5790 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr);
5795 S.NoteDeletedFunction(Best->Function);
5800 void InitializationSequence::PrintInitLocationNote(Sema &S,
5801 const InitializedEntity &Entity) {
5802 if (Entity.isParameterKind() && Entity.getDecl()) {
5803 if (Entity.getDecl()->getLocation().isInvalid())
5806 if (Entity.getDecl()->getDeclName())
5807 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here)
5808 << Entity.getDecl()->getDeclName();
5810 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here);
5812 else if (Entity.getKind() == InitializedEntity::EK_RelatedResult &&
5813 Entity.getMethodDecl())
5814 S.Diag(Entity.getMethodDecl()->getLocation(),
5815 diag::note_method_return_type_change)
5816 << Entity.getMethodDecl()->getDeclName();
5819 /// Returns true if the parameters describe a constructor initialization of
5820 /// an explicit temporary object, e.g. "Point(x, y)".
5821 static bool isExplicitTemporary(const InitializedEntity &Entity,
5822 const InitializationKind &Kind,
5824 switch (Entity.getKind()) {
5825 case InitializedEntity::EK_Temporary:
5826 case InitializedEntity::EK_CompoundLiteralInit:
5827 case InitializedEntity::EK_RelatedResult:
5833 switch (Kind.getKind()) {
5834 case InitializationKind::IK_DirectList:
5836 // FIXME: Hack to work around cast weirdness.
5837 case InitializationKind::IK_Direct:
5838 case InitializationKind::IK_Value:
5839 return NumArgs != 1;
5846 PerformConstructorInitialization(Sema &S,
5847 const InitializedEntity &Entity,
5848 const InitializationKind &Kind,
5850 const InitializationSequence::Step& Step,
5851 bool &ConstructorInitRequiresZeroInit,
5852 bool IsListInitialization,
5853 bool IsStdInitListInitialization,
5854 SourceLocation LBraceLoc,
5855 SourceLocation RBraceLoc) {
5856 unsigned NumArgs = Args.size();
5857 CXXConstructorDecl *Constructor
5858 = cast<CXXConstructorDecl>(Step.Function.Function);
5859 bool HadMultipleCandidates = Step.Function.HadMultipleCandidates;
5861 // Build a call to the selected constructor.
5862 SmallVector<Expr*, 8> ConstructorArgs;
5863 SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid())
5864 ? Kind.getEqualLoc()
5865 : Kind.getLocation();
5867 if (Kind.getKind() == InitializationKind::IK_Default) {
5868 // Force even a trivial, implicit default constructor to be
5869 // semantically checked. We do this explicitly because we don't build
5870 // the definition for completely trivial constructors.
5871 assert(Constructor->getParent() && "No parent class for constructor.");
5872 if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
5873 Constructor->isTrivial() && !Constructor->isUsed(false))
5874 S.DefineImplicitDefaultConstructor(Loc, Constructor);
5877 ExprResult CurInit((Expr *)nullptr);
5879 // C++ [over.match.copy]p1:
5880 // - When initializing a temporary to be bound to the first parameter
5881 // of a constructor that takes a reference to possibly cv-qualified
5882 // T as its first argument, called with a single argument in the
5883 // context of direct-initialization, explicit conversion functions
5884 // are also considered.
5885 bool AllowExplicitConv =
5886 Kind.AllowExplicit() && !Kind.isCopyInit() && Args.size() == 1 &&
5887 hasCopyOrMoveCtorParam(S.Context,
5888 getConstructorInfo(Step.Function.FoundDecl));
5890 // Determine the arguments required to actually perform the constructor
5892 if (S.CompleteConstructorCall(Constructor, Args,
5893 Loc, ConstructorArgs,
5895 IsListInitialization))
5899 if (isExplicitTemporary(Entity, Kind, NumArgs)) {
5900 // An explicitly-constructed temporary, e.g., X(1, 2).
5901 if (S.DiagnoseUseOfDecl(Constructor, Loc))
5904 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
5906 TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc);
5907 SourceRange ParenOrBraceRange =
5908 (Kind.getKind() == InitializationKind::IK_DirectList)
5909 ? SourceRange(LBraceLoc, RBraceLoc)
5910 : Kind.getParenRange();
5912 if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(
5913 Step.Function.FoundDecl.getDecl())) {
5914 Constructor = S.findInheritingConstructor(Loc, Constructor, Shadow);
5915 if (S.DiagnoseUseOfDecl(Constructor, Loc))
5918 S.MarkFunctionReferenced(Loc, Constructor);
5920 CurInit = new (S.Context) CXXTemporaryObjectExpr(
5921 S.Context, Constructor, TSInfo,
5922 ConstructorArgs, ParenOrBraceRange, HadMultipleCandidates,
5923 IsListInitialization, IsStdInitListInitialization,
5924 ConstructorInitRequiresZeroInit);
5926 CXXConstructExpr::ConstructionKind ConstructKind =
5927 CXXConstructExpr::CK_Complete;
5929 if (Entity.getKind() == InitializedEntity::EK_Base) {
5930 ConstructKind = Entity.getBaseSpecifier()->isVirtual() ?
5931 CXXConstructExpr::CK_VirtualBase :
5932 CXXConstructExpr::CK_NonVirtualBase;
5933 } else if (Entity.getKind() == InitializedEntity::EK_Delegating) {
5934 ConstructKind = CXXConstructExpr::CK_Delegating;
5937 // Only get the parenthesis or brace range if it is a list initialization or
5938 // direct construction.
5939 SourceRange ParenOrBraceRange;
5940 if (IsListInitialization)
5941 ParenOrBraceRange = SourceRange(LBraceLoc, RBraceLoc);
5942 else if (Kind.getKind() == InitializationKind::IK_Direct)
5943 ParenOrBraceRange = Kind.getParenRange();
5945 // If the entity allows NRVO, mark the construction as elidable
5947 if (Entity.allowsNRVO())
5948 CurInit = S.BuildCXXConstructExpr(Loc, Step.Type,
5949 Step.Function.FoundDecl,
5950 Constructor, /*Elidable=*/true,
5952 HadMultipleCandidates,
5953 IsListInitialization,
5954 IsStdInitListInitialization,
5955 ConstructorInitRequiresZeroInit,
5959 CurInit = S.BuildCXXConstructExpr(Loc, Step.Type,
5960 Step.Function.FoundDecl,
5963 HadMultipleCandidates,
5964 IsListInitialization,
5965 IsStdInitListInitialization,
5966 ConstructorInitRequiresZeroInit,
5970 if (CurInit.isInvalid())
5973 // Only check access if all of that succeeded.
5974 S.CheckConstructorAccess(Loc, Constructor, Step.Function.FoundDecl, Entity);
5975 if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc))
5978 if (shouldBindAsTemporary(Entity))
5979 CurInit = S.MaybeBindToTemporary(CurInit.get());
5984 /// Determine whether the specified InitializedEntity definitely has a lifetime
5985 /// longer than the current full-expression. Conservatively returns false if
5988 InitializedEntityOutlivesFullExpression(const InitializedEntity &Entity) {
5989 const InitializedEntity *Top = &Entity;
5990 while (Top->getParent())
5991 Top = Top->getParent();
5993 switch (Top->getKind()) {
5994 case InitializedEntity::EK_Variable:
5995 case InitializedEntity::EK_Result:
5996 case InitializedEntity::EK_Exception:
5997 case InitializedEntity::EK_Member:
5998 case InitializedEntity::EK_Binding:
5999 case InitializedEntity::EK_New:
6000 case InitializedEntity::EK_Base:
6001 case InitializedEntity::EK_Delegating:
6004 case InitializedEntity::EK_ArrayElement:
6005 case InitializedEntity::EK_VectorElement:
6006 case InitializedEntity::EK_BlockElement:
6007 case InitializedEntity::EK_ComplexElement:
6008 // Could not determine what the full initialization is. Assume it might not
6009 // outlive the full-expression.
6012 case InitializedEntity::EK_Parameter:
6013 case InitializedEntity::EK_Parameter_CF_Audited:
6014 case InitializedEntity::EK_Temporary:
6015 case InitializedEntity::EK_LambdaCapture:
6016 case InitializedEntity::EK_CompoundLiteralInit:
6017 case InitializedEntity::EK_RelatedResult:
6018 // The entity being initialized might not outlive the full-expression.
6022 llvm_unreachable("unknown entity kind");
6025 /// Determine the declaration which an initialized entity ultimately refers to,
6026 /// for the purpose of lifetime-extending a temporary bound to a reference in
6027 /// the initialization of \p Entity.
6028 static const InitializedEntity *getEntityForTemporaryLifetimeExtension(
6029 const InitializedEntity *Entity,
6030 const InitializedEntity *FallbackDecl = nullptr) {
6031 // C++11 [class.temporary]p5:
6032 switch (Entity->getKind()) {
6033 case InitializedEntity::EK_Variable:
6034 // The temporary [...] persists for the lifetime of the reference
6037 case InitializedEntity::EK_Member:
6038 // For subobjects, we look at the complete object.
6039 if (Entity->getParent())
6040 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
6044 // -- A temporary bound to a reference member in a constructor's
6045 // ctor-initializer persists until the constructor exits.
6048 case InitializedEntity::EK_Binding:
6049 // Per [dcl.decomp]p3, the binding is treated as a variable of reference
6053 case InitializedEntity::EK_Parameter:
6054 case InitializedEntity::EK_Parameter_CF_Audited:
6055 // -- A temporary bound to a reference parameter in a function call
6056 // persists until the completion of the full-expression containing
6058 case InitializedEntity::EK_Result:
6059 // -- The lifetime of a temporary bound to the returned value in a
6060 // function return statement is not extended; the temporary is
6061 // destroyed at the end of the full-expression in the return statement.
6062 case InitializedEntity::EK_New:
6063 // -- A temporary bound to a reference in a new-initializer persists
6064 // until the completion of the full-expression containing the
6068 case InitializedEntity::EK_Temporary:
6069 case InitializedEntity::EK_CompoundLiteralInit:
6070 case InitializedEntity::EK_RelatedResult:
6071 // We don't yet know the storage duration of the surrounding temporary.
6072 // Assume it's got full-expression duration for now, it will patch up our
6073 // storage duration if that's not correct.
6076 case InitializedEntity::EK_ArrayElement:
6077 // For subobjects, we look at the complete object.
6078 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
6081 case InitializedEntity::EK_Base:
6082 // For subobjects, we look at the complete object.
6083 if (Entity->getParent())
6084 return getEntityForTemporaryLifetimeExtension(Entity->getParent(),
6087 case InitializedEntity::EK_Delegating:
6088 // We can reach this case for aggregate initialization in a constructor:
6089 // struct A { int &&r; };
6090 // struct B : A { B() : A{0} {} };
6091 // In this case, use the innermost field decl as the context.
6092 return FallbackDecl;
6094 case InitializedEntity::EK_BlockElement:
6095 case InitializedEntity::EK_LambdaCapture:
6096 case InitializedEntity::EK_Exception:
6097 case InitializedEntity::EK_VectorElement:
6098 case InitializedEntity::EK_ComplexElement:
6101 llvm_unreachable("unknown entity kind");
6104 static void performLifetimeExtension(Expr *Init,
6105 const InitializedEntity *ExtendingEntity);
6107 /// Update a glvalue expression that is used as the initializer of a reference
6108 /// to note that its lifetime is extended.
6109 /// \return \c true if any temporary had its lifetime extended.
6111 performReferenceExtension(Expr *Init,
6112 const InitializedEntity *ExtendingEntity) {
6113 // Walk past any constructs which we can lifetime-extend across.
6118 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
6119 if (ILE->getNumInits() == 1 && ILE->isGLValue()) {
6120 // This is just redundant braces around an initializer. Step over it.
6121 Init = ILE->getInit(0);
6125 // Step over any subobject adjustments; we may have a materialized
6126 // temporary inside them.
6127 Init = const_cast<Expr *>(Init->skipRValueSubobjectAdjustments());
6129 // Per current approach for DR1376, look through casts to reference type
6130 // when performing lifetime extension.
6131 if (CastExpr *CE = dyn_cast<CastExpr>(Init))
6132 if (CE->getSubExpr()->isGLValue())
6133 Init = CE->getSubExpr();
6135 // Per the current approach for DR1299, look through array element access
6136 // when performing lifetime extension.
6137 if (auto *ASE = dyn_cast<ArraySubscriptExpr>(Init))
6138 Init = ASE->getBase();
6139 } while (Init != Old);
6141 if (MaterializeTemporaryExpr *ME = dyn_cast<MaterializeTemporaryExpr>(Init)) {
6142 // Update the storage duration of the materialized temporary.
6143 // FIXME: Rebuild the expression instead of mutating it.
6144 ME->setExtendingDecl(ExtendingEntity->getDecl(),
6145 ExtendingEntity->allocateManglingNumber());
6146 performLifetimeExtension(ME->GetTemporaryExpr(), ExtendingEntity);
6153 /// Update a prvalue expression that is going to be materialized as a
6154 /// lifetime-extended temporary.
6155 static void performLifetimeExtension(Expr *Init,
6156 const InitializedEntity *ExtendingEntity) {
6157 // Dig out the expression which constructs the extended temporary.
6158 Init = const_cast<Expr *>(Init->skipRValueSubobjectAdjustments());
6160 if (CXXBindTemporaryExpr *BTE = dyn_cast<CXXBindTemporaryExpr>(Init))
6161 Init = BTE->getSubExpr();
6163 if (CXXStdInitializerListExpr *ILE =
6164 dyn_cast<CXXStdInitializerListExpr>(Init)) {
6165 performReferenceExtension(ILE->getSubExpr(), ExtendingEntity);
6169 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
6170 if (ILE->getType()->isArrayType()) {
6171 for (unsigned I = 0, N = ILE->getNumInits(); I != N; ++I)
6172 performLifetimeExtension(ILE->getInit(I), ExtendingEntity);
6176 if (CXXRecordDecl *RD = ILE->getType()->getAsCXXRecordDecl()) {
6177 assert(RD->isAggregate() && "aggregate init on non-aggregate");
6179 // If we lifetime-extend a braced initializer which is initializing an
6180 // aggregate, and that aggregate contains reference members which are
6181 // bound to temporaries, those temporaries are also lifetime-extended.
6182 if (RD->isUnion() && ILE->getInitializedFieldInUnion() &&
6183 ILE->getInitializedFieldInUnion()->getType()->isReferenceType())
6184 performReferenceExtension(ILE->getInit(0), ExtendingEntity);
6187 for (const auto *I : RD->fields()) {
6188 if (Index >= ILE->getNumInits())
6190 if (I->isUnnamedBitfield())
6192 Expr *SubInit = ILE->getInit(Index);
6193 if (I->getType()->isReferenceType())
6194 performReferenceExtension(SubInit, ExtendingEntity);
6195 else if (isa<InitListExpr>(SubInit) ||
6196 isa<CXXStdInitializerListExpr>(SubInit))
6197 // This may be either aggregate-initialization of a member or
6198 // initialization of a std::initializer_list object. Either way,
6199 // we should recursively lifetime-extend that initializer.
6200 performLifetimeExtension(SubInit, ExtendingEntity);
6208 static void warnOnLifetimeExtension(Sema &S, const InitializedEntity &Entity,
6209 const Expr *Init, bool IsInitializerList,
6210 const ValueDecl *ExtendingDecl) {
6211 // Warn if a field lifetime-extends a temporary.
6212 if (isa<FieldDecl>(ExtendingDecl)) {
6213 if (IsInitializerList) {
6214 S.Diag(Init->getExprLoc(), diag::warn_dangling_std_initializer_list)
6215 << /*at end of constructor*/true;
6219 bool IsSubobjectMember = false;
6220 for (const InitializedEntity *Ent = Entity.getParent(); Ent;
6221 Ent = Ent->getParent()) {
6222 if (Ent->getKind() != InitializedEntity::EK_Base) {
6223 IsSubobjectMember = true;
6227 S.Diag(Init->getExprLoc(),
6228 diag::warn_bind_ref_member_to_temporary)
6229 << ExtendingDecl << Init->getSourceRange()
6230 << IsSubobjectMember << IsInitializerList;
6231 if (IsSubobjectMember)
6232 S.Diag(ExtendingDecl->getLocation(),
6233 diag::note_ref_subobject_of_member_declared_here);
6235 S.Diag(ExtendingDecl->getLocation(),
6236 diag::note_ref_or_ptr_member_declared_here)
6237 << /*is pointer*/false;
6241 static void DiagnoseNarrowingInInitList(Sema &S,
6242 const ImplicitConversionSequence &ICS,
6243 QualType PreNarrowingType,
6244 QualType EntityType,
6245 const Expr *PostInit);
6247 /// Provide warnings when std::move is used on construction.
6248 static void CheckMoveOnConstruction(Sema &S, const Expr *InitExpr,
6249 bool IsReturnStmt) {
6253 if (!S.ActiveTemplateInstantiations.empty())
6256 QualType DestType = InitExpr->getType();
6257 if (!DestType->isRecordType())
6260 unsigned DiagID = 0;
6262 const CXXConstructExpr *CCE =
6263 dyn_cast<CXXConstructExpr>(InitExpr->IgnoreParens());
6264 if (!CCE || CCE->getNumArgs() != 1)
6267 if (!CCE->getConstructor()->isCopyOrMoveConstructor())
6270 InitExpr = CCE->getArg(0)->IgnoreImpCasts();
6273 // Find the std::move call and get the argument.
6274 const CallExpr *CE = dyn_cast<CallExpr>(InitExpr->IgnoreParens());
6275 if (!CE || CE->getNumArgs() != 1)
6278 const FunctionDecl *MoveFunction = CE->getDirectCallee();
6279 if (!MoveFunction || !MoveFunction->isInStdNamespace() ||
6280 !MoveFunction->getIdentifier() ||
6281 !MoveFunction->getIdentifier()->isStr("move"))
6284 const Expr *Arg = CE->getArg(0)->IgnoreImplicit();
6287 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Arg->IgnoreParenImpCasts());
6288 if (!DRE || DRE->refersToEnclosingVariableOrCapture())
6291 const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl());
6292 if (!VD || !VD->hasLocalStorage())
6295 QualType SourceType = VD->getType();
6296 if (!SourceType->isRecordType())
6299 if (!S.Context.hasSameUnqualifiedType(DestType, SourceType)) {
6303 // If we're returning a function parameter, copy elision
6305 if (isa<ParmVarDecl>(VD))
6306 DiagID = diag::warn_redundant_move_on_return;
6308 DiagID = diag::warn_pessimizing_move_on_return;
6310 DiagID = diag::warn_pessimizing_move_on_initialization;
6311 const Expr *ArgStripped = Arg->IgnoreImplicit()->IgnoreParens();
6312 if (!ArgStripped->isRValue() || !ArgStripped->getType()->isRecordType())
6316 S.Diag(CE->getLocStart(), DiagID);
6318 // Get all the locations for a fix-it. Don't emit the fix-it if any location
6319 // is within a macro.
6320 SourceLocation CallBegin = CE->getCallee()->getLocStart();
6321 if (CallBegin.isMacroID())
6323 SourceLocation RParen = CE->getRParenLoc();
6324 if (RParen.isMacroID())
6326 SourceLocation LParen;
6327 SourceLocation ArgLoc = Arg->getLocStart();
6329 // Special testing for the argument location. Since the fix-it needs the
6330 // location right before the argument, the argument location can be in a
6331 // macro only if it is at the beginning of the macro.
6332 while (ArgLoc.isMacroID() &&
6333 S.getSourceManager().isAtStartOfImmediateMacroExpansion(ArgLoc)) {
6334 ArgLoc = S.getSourceManager().getImmediateExpansionRange(ArgLoc).first;
6337 if (LParen.isMacroID())
6340 LParen = ArgLoc.getLocWithOffset(-1);
6342 S.Diag(CE->getLocStart(), diag::note_remove_move)
6343 << FixItHint::CreateRemoval(SourceRange(CallBegin, LParen))
6344 << FixItHint::CreateRemoval(SourceRange(RParen, RParen));
6347 static void CheckForNullPointerDereference(Sema &S, const Expr *E) {
6348 // Check to see if we are dereferencing a null pointer. If so, this is
6349 // undefined behavior, so warn about it. This only handles the pattern
6350 // "*null", which is a very syntactic check.
6351 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts()))
6352 if (UO->getOpcode() == UO_Deref &&
6353 UO->getSubExpr()->IgnoreParenCasts()->
6354 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull)) {
6355 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
6356 S.PDiag(diag::warn_binding_null_to_reference)
6357 << UO->getSubExpr()->getSourceRange());
6361 MaterializeTemporaryExpr *
6362 Sema::CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary,
6363 bool BoundToLvalueReference) {
6364 auto MTE = new (Context)
6365 MaterializeTemporaryExpr(T, Temporary, BoundToLvalueReference);
6367 // Order an ExprWithCleanups for lifetime marks.
6369 // TODO: It'll be good to have a single place to check the access of the
6370 // destructor and generate ExprWithCleanups for various uses. Currently these
6371 // are done in both CreateMaterializeTemporaryExpr and MaybeBindToTemporary,
6372 // but there may be a chance to merge them.
6373 Cleanup.setExprNeedsCleanups(false);
6377 ExprResult Sema::TemporaryMaterializationConversion(Expr *E) {
6378 // In C++98, we don't want to implicitly create an xvalue.
6379 // FIXME: This means that AST consumers need to deal with "prvalues" that
6380 // denote materialized temporaries. Maybe we should add another ValueKind
6381 // for "xvalue pretending to be a prvalue" for C++98 support.
6382 if (!E->isRValue() || !getLangOpts().CPlusPlus11)
6385 // C++1z [conv.rval]/1: T shall be a complete type.
6386 // FIXME: Does this ever matter (can we form a prvalue of incomplete type)?
6387 // If so, we should check for a non-abstract class type here too.
6388 QualType T = E->getType();
6389 if (RequireCompleteType(E->getExprLoc(), T, diag::err_incomplete_type))
6392 return CreateMaterializeTemporaryExpr(E->getType(), E, false);
6396 InitializationSequence::Perform(Sema &S,
6397 const InitializedEntity &Entity,
6398 const InitializationKind &Kind,
6400 QualType *ResultType) {
6402 Diagnose(S, Entity, Kind, Args);
6405 if (!ZeroInitializationFixit.empty()) {
6406 unsigned DiagID = diag::err_default_init_const;
6407 if (Decl *D = Entity.getDecl())
6408 if (S.getLangOpts().MSVCCompat && D->hasAttr<SelectAnyAttr>())
6409 DiagID = diag::ext_default_init_const;
6411 // The initialization would have succeeded with this fixit. Since the fixit
6412 // is on the error, we need to build a valid AST in this case, so this isn't
6413 // handled in the Failed() branch above.
6414 QualType DestType = Entity.getType();
6415 S.Diag(Kind.getLocation(), DiagID)
6416 << DestType << (bool)DestType->getAs<RecordType>()
6417 << FixItHint::CreateInsertion(ZeroInitializationFixitLoc,
6418 ZeroInitializationFixit);
6421 if (getKind() == DependentSequence) {
6422 // If the declaration is a non-dependent, incomplete array type
6423 // that has an initializer, then its type will be completed once
6424 // the initializer is instantiated.
6425 if (ResultType && !Entity.getType()->isDependentType() &&
6427 QualType DeclType = Entity.getType();
6428 if (const IncompleteArrayType *ArrayT
6429 = S.Context.getAsIncompleteArrayType(DeclType)) {
6430 // FIXME: We don't currently have the ability to accurately
6431 // compute the length of an initializer list without
6432 // performing full type-checking of the initializer list
6433 // (since we have to determine where braces are implicitly
6434 // introduced and such). So, we fall back to making the array
6435 // type a dependently-sized array type with no specified
6437 if (isa<InitListExpr>((Expr *)Args[0])) {
6438 SourceRange Brackets;
6440 // Scavange the location of the brackets from the entity, if we can.
6441 if (auto *DD = dyn_cast_or_null<DeclaratorDecl>(Entity.getDecl())) {
6442 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) {
6443 TypeLoc TL = TInfo->getTypeLoc();
6444 if (IncompleteArrayTypeLoc ArrayLoc =
6445 TL.getAs<IncompleteArrayTypeLoc>())
6446 Brackets = ArrayLoc.getBracketsRange();
6451 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(),
6452 /*NumElts=*/nullptr,
6453 ArrayT->getSizeModifier(),
6454 ArrayT->getIndexTypeCVRQualifiers(),
6460 if (Kind.getKind() == InitializationKind::IK_Direct &&
6461 !Kind.isExplicitCast()) {
6462 // Rebuild the ParenListExpr.
6463 SourceRange ParenRange = Kind.getParenRange();
6464 return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(),
6467 assert(Kind.getKind() == InitializationKind::IK_Copy ||
6468 Kind.isExplicitCast() ||
6469 Kind.getKind() == InitializationKind::IK_DirectList);
6470 return ExprResult(Args[0]);
6473 // No steps means no initialization.
6475 return ExprResult((Expr *)nullptr);
6477 if (S.getLangOpts().CPlusPlus11 && Entity.getType()->isReferenceType() &&
6478 Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
6479 !Entity.isParameterKind()) {
6480 // Produce a C++98 compatibility warning if we are initializing a reference
6481 // from an initializer list. For parameters, we produce a better warning
6483 Expr *Init = Args[0];
6484 S.Diag(Init->getLocStart(), diag::warn_cxx98_compat_reference_list_init)
6485 << Init->getSourceRange();
6488 // Diagnose cases where we initialize a pointer to an array temporary, and the
6489 // pointer obviously outlives the temporary.
6490 if (Args.size() == 1 && Args[0]->getType()->isArrayType() &&
6491 Entity.getType()->isPointerType() &&
6492 InitializedEntityOutlivesFullExpression(Entity)) {
6493 const Expr *Init = Args[0]->skipRValueSubobjectAdjustments();
6494 if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Init))
6495 Init = MTE->GetTemporaryExpr();
6496 Expr::LValueClassification Kind = Init->ClassifyLValue(S.Context);
6497 if (Kind == Expr::LV_ClassTemporary || Kind == Expr::LV_ArrayTemporary)
6498 S.Diag(Init->getLocStart(), diag::warn_temporary_array_to_pointer_decay)
6499 << Init->getSourceRange();
6502 QualType DestType = Entity.getType().getNonReferenceType();
6503 // FIXME: Ugly hack around the fact that Entity.getType() is not
6504 // the same as Entity.getDecl()->getType() in cases involving type merging,
6505 // and we want latter when it makes sense.
6507 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() :
6510 ExprResult CurInit((Expr *)nullptr);
6511 SmallVector<Expr*, 4> ArrayLoopCommonExprs;
6513 // For initialization steps that start with a single initializer,
6514 // grab the only argument out the Args and place it into the "current"
6516 switch (Steps.front().Kind) {
6517 case SK_ResolveAddressOfOverloadedFunction:
6518 case SK_CastDerivedToBaseRValue:
6519 case SK_CastDerivedToBaseXValue:
6520 case SK_CastDerivedToBaseLValue:
6521 case SK_BindReference:
6522 case SK_BindReferenceToTemporary:
6524 case SK_ExtraneousCopyToTemporary:
6525 case SK_UserConversion:
6526 case SK_QualificationConversionLValue:
6527 case SK_QualificationConversionXValue:
6528 case SK_QualificationConversionRValue:
6529 case SK_AtomicConversion:
6530 case SK_LValueToRValue:
6531 case SK_ConversionSequence:
6532 case SK_ConversionSequenceNoNarrowing:
6533 case SK_ListInitialization:
6534 case SK_UnwrapInitList:
6535 case SK_RewrapInitList:
6536 case SK_CAssignment:
6538 case SK_ObjCObjectConversion:
6539 case SK_ArrayLoopIndex:
6540 case SK_ArrayLoopInit:
6542 case SK_GNUArrayInit:
6543 case SK_ParenthesizedArrayInit:
6544 case SK_PassByIndirectCopyRestore:
6545 case SK_PassByIndirectRestore:
6546 case SK_ProduceObjCObject:
6547 case SK_StdInitializerList:
6548 case SK_OCLSamplerInit:
6549 case SK_OCLZeroEvent:
6550 case SK_OCLZeroQueue: {
6551 assert(Args.size() == 1);
6553 if (!CurInit.get()) return ExprError();
6557 case SK_ConstructorInitialization:
6558 case SK_ConstructorInitializationFromList:
6559 case SK_StdInitializerListConstructorCall:
6560 case SK_ZeroInitialization:
6564 // C++ [class.abstract]p2:
6565 // no objects of an abstract class can be created except as subobjects
6566 // of a class derived from it
6567 auto checkAbstractType = [&](QualType T) -> bool {
6568 if (Entity.getKind() == InitializedEntity::EK_Base ||
6569 Entity.getKind() == InitializedEntity::EK_Delegating)
6571 return S.RequireNonAbstractType(Kind.getLocation(), T,
6572 diag::err_allocation_of_abstract_type);
6575 // Walk through the computed steps for the initialization sequence,
6576 // performing the specified conversions along the way.
6577 bool ConstructorInitRequiresZeroInit = false;
6578 for (step_iterator Step = step_begin(), StepEnd = step_end();
6579 Step != StepEnd; ++Step) {
6580 if (CurInit.isInvalid())
6583 QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType();
6585 switch (Step->Kind) {
6586 case SK_ResolveAddressOfOverloadedFunction:
6587 // Overload resolution determined which function invoke; update the
6588 // initializer to reflect that choice.
6589 S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl);
6590 if (S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()))
6592 CurInit = S.FixOverloadedFunctionReference(CurInit,
6593 Step->Function.FoundDecl,
6594 Step->Function.Function);
6597 case SK_CastDerivedToBaseRValue:
6598 case SK_CastDerivedToBaseXValue:
6599 case SK_CastDerivedToBaseLValue: {
6600 // We have a derived-to-base cast that produces either an rvalue or an
6601 // lvalue. Perform that cast.
6603 CXXCastPath BasePath;
6605 // Casts to inaccessible base classes are allowed with C-style casts.
6606 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast();
6607 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type,
6608 CurInit.get()->getLocStart(),
6609 CurInit.get()->getSourceRange(),
6610 &BasePath, IgnoreBaseAccess))
6614 Step->Kind == SK_CastDerivedToBaseLValue ?
6616 (Step->Kind == SK_CastDerivedToBaseXValue ?
6620 ImplicitCastExpr::Create(S.Context, Step->Type, CK_DerivedToBase,
6621 CurInit.get(), &BasePath, VK);
6625 case SK_BindReference:
6626 // Reference binding does not have any corresponding ASTs.
6628 // Check exception specifications
6629 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
6632 // Even though we didn't materialize a temporary, the binding may still
6633 // extend the lifetime of a temporary. This happens if we bind a reference
6634 // to the result of a cast to reference type.
6635 if (const InitializedEntity *ExtendingEntity =
6636 getEntityForTemporaryLifetimeExtension(&Entity))
6637 if (performReferenceExtension(CurInit.get(), ExtendingEntity))
6638 warnOnLifetimeExtension(S, Entity, CurInit.get(),
6639 /*IsInitializerList=*/false,
6640 ExtendingEntity->getDecl());
6642 CheckForNullPointerDereference(S, CurInit.get());
6645 case SK_BindReferenceToTemporary: {
6646 // Make sure the "temporary" is actually an rvalue.
6647 assert(CurInit.get()->isRValue() && "not a temporary");
6649 // Check exception specifications
6650 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType))
6653 // Materialize the temporary into memory.
6654 MaterializeTemporaryExpr *MTE = S.CreateMaterializeTemporaryExpr(
6655 Step->Type, CurInit.get(), Entity.getType()->isLValueReferenceType());
6657 // Maybe lifetime-extend the temporary's subobjects to match the
6658 // entity's lifetime.
6659 if (const InitializedEntity *ExtendingEntity =
6660 getEntityForTemporaryLifetimeExtension(&Entity))
6661 if (performReferenceExtension(MTE, ExtendingEntity))
6662 warnOnLifetimeExtension(S, Entity, CurInit.get(),
6663 /*IsInitializerList=*/false,
6664 ExtendingEntity->getDecl());
6666 // If we're binding to an Objective-C object that has lifetime, we
6667 // need cleanups. Likewise if we're extending this temporary to automatic
6668 // storage duration -- we need to register its cleanup during the
6669 // full-expression's cleanups.
6670 if ((S.getLangOpts().ObjCAutoRefCount &&
6671 MTE->getType()->isObjCLifetimeType()) ||
6672 (MTE->getStorageDuration() == SD_Automatic &&
6673 MTE->getType().isDestructedType()))
6674 S.Cleanup.setExprNeedsCleanups(true);
6681 if (checkAbstractType(Step->Type))
6684 // If the overall initialization is initializing a temporary, we already
6685 // bound our argument if it was necessary to do so. If not (if we're
6686 // ultimately initializing a non-temporary), our argument needs to be
6687 // bound since it's initializing a function parameter.
6688 // FIXME: This is a mess. Rationalize temporary destruction.
6689 if (!shouldBindAsTemporary(Entity))
6690 CurInit = S.MaybeBindToTemporary(CurInit.get());
6691 CurInit = CopyObject(S, Step->Type, Entity, CurInit,
6692 /*IsExtraneousCopy=*/false);
6695 case SK_ExtraneousCopyToTemporary:
6696 CurInit = CopyObject(S, Step->Type, Entity, CurInit,
6697 /*IsExtraneousCopy=*/true);
6700 case SK_UserConversion: {
6701 // We have a user-defined conversion that invokes either a constructor
6702 // or a conversion function.
6704 FunctionDecl *Fn = Step->Function.Function;
6705 DeclAccessPair FoundFn = Step->Function.FoundDecl;
6706 bool HadMultipleCandidates = Step->Function.HadMultipleCandidates;
6707 bool CreatedObject = false;
6708 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) {
6709 // Build a call to the selected constructor.
6710 SmallVector<Expr*, 8> ConstructorArgs;
6711 SourceLocation Loc = CurInit.get()->getLocStart();
6713 // Determine the arguments required to actually perform the constructor
6715 Expr *Arg = CurInit.get();
6716 if (S.CompleteConstructorCall(Constructor,
6717 MultiExprArg(&Arg, 1),
6718 Loc, ConstructorArgs))
6721 // Build an expression that constructs a temporary.
6722 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type,
6723 FoundFn, Constructor,
6725 HadMultipleCandidates,
6727 /*StdInitListInit*/ false,
6729 CXXConstructExpr::CK_Complete,
6731 if (CurInit.isInvalid())
6734 S.CheckConstructorAccess(Kind.getLocation(), Constructor, FoundFn,
6736 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
6739 CastKind = CK_ConstructorConversion;
6740 CreatedObject = true;
6742 // Build a call to the conversion function.
6743 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn);
6744 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), nullptr,
6746 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()))
6749 // FIXME: Should we move this initialization into a separate
6750 // derived-to-base conversion? I believe the answer is "no", because
6751 // we don't want to turn off access control here for c-style casts.
6752 CurInit = S.PerformObjectArgumentInitialization(CurInit.get(),
6753 /*Qualifier=*/nullptr,
6754 FoundFn, Conversion);
6755 if (CurInit.isInvalid())
6758 // Build the actual call to the conversion function.
6759 CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion,
6760 HadMultipleCandidates);
6761 if (CurInit.isInvalid())
6764 CastKind = CK_UserDefinedConversion;
6765 CreatedObject = Conversion->getReturnType()->isRecordType();
6768 if (CreatedObject && checkAbstractType(CurInit.get()->getType()))
6771 CurInit = ImplicitCastExpr::Create(S.Context, CurInit.get()->getType(),
6772 CastKind, CurInit.get(), nullptr,
6773 CurInit.get()->getValueKind());
6775 if (shouldBindAsTemporary(Entity))
6776 // The overall entity is temporary, so this expression should be
6777 // destroyed at the end of its full-expression.
6778 CurInit = S.MaybeBindToTemporary(CurInit.getAs<Expr>());
6779 else if (CreatedObject && shouldDestroyEntity(Entity)) {
6780 // The object outlasts the full-expression, but we need to prepare for
6781 // a destructor being run on it.
6782 // FIXME: It makes no sense to do this here. This should happen
6783 // regardless of how we initialized the entity.
6784 QualType T = CurInit.get()->getType();
6785 if (const RecordType *Record = T->getAs<RecordType>()) {
6786 CXXDestructorDecl *Destructor
6787 = S.LookupDestructor(cast<CXXRecordDecl>(Record->getDecl()));
6788 S.CheckDestructorAccess(CurInit.get()->getLocStart(), Destructor,
6789 S.PDiag(diag::err_access_dtor_temp) << T);
6790 S.MarkFunctionReferenced(CurInit.get()->getLocStart(), Destructor);
6791 if (S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getLocStart()))
6798 case SK_QualificationConversionLValue:
6799 case SK_QualificationConversionXValue:
6800 case SK_QualificationConversionRValue: {
6801 // Perform a qualification conversion; these can never go wrong.
6803 Step->Kind == SK_QualificationConversionLValue ?
6805 (Step->Kind == SK_QualificationConversionXValue ?
6808 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type, CK_NoOp, VK);
6812 case SK_AtomicConversion: {
6813 assert(CurInit.get()->isRValue() && "cannot convert glvalue to atomic");
6814 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
6815 CK_NonAtomicToAtomic, VK_RValue);
6819 case SK_LValueToRValue: {
6820 assert(CurInit.get()->isGLValue() && "cannot load from a prvalue");
6821 CurInit = ImplicitCastExpr::Create(S.Context, Step->Type,
6822 CK_LValueToRValue, CurInit.get(),
6823 /*BasePath=*/nullptr, VK_RValue);
6827 case SK_ConversionSequence:
6828 case SK_ConversionSequenceNoNarrowing: {
6829 Sema::CheckedConversionKind CCK
6830 = Kind.isCStyleCast()? Sema::CCK_CStyleCast
6831 : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast
6832 : Kind.isExplicitCast()? Sema::CCK_OtherCast
6833 : Sema::CCK_ImplicitConversion;
6834 ExprResult CurInitExprRes =
6835 S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS,
6836 getAssignmentAction(Entity), CCK);
6837 if (CurInitExprRes.isInvalid())
6840 S.DiscardMisalignedMemberAddress(Step->Type.getTypePtr(), CurInit.get());
6842 CurInit = CurInitExprRes;
6844 if (Step->Kind == SK_ConversionSequenceNoNarrowing &&
6845 S.getLangOpts().CPlusPlus)
6846 DiagnoseNarrowingInInitList(S, *Step->ICS, SourceType, Entity.getType(),
6852 case SK_ListInitialization: {
6853 if (checkAbstractType(Step->Type))
6856 InitListExpr *InitList = cast<InitListExpr>(CurInit.get());
6857 // If we're not initializing the top-level entity, we need to create an
6858 // InitializeTemporary entity for our target type.
6859 QualType Ty = Step->Type;
6860 bool IsTemporary = !S.Context.hasSameType(Entity.getType(), Ty);
6861 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty);
6862 InitializedEntity InitEntity = IsTemporary ? TempEntity : Entity;
6863 InitListChecker PerformInitList(S, InitEntity,
6864 InitList, Ty, /*VerifyOnly=*/false,
6865 /*TreatUnavailableAsInvalid=*/false);
6866 if (PerformInitList.HadError())
6869 // Hack: We must update *ResultType if available in order to set the
6870 // bounds of arrays, e.g. in 'int ar[] = {1, 2, 3};'.
6871 // Worst case: 'const int (&arref)[] = {1, 2, 3};'.
6873 ResultType->getNonReferenceType()->isIncompleteArrayType()) {
6874 if ((*ResultType)->isRValueReferenceType())
6875 Ty = S.Context.getRValueReferenceType(Ty);
6876 else if ((*ResultType)->isLValueReferenceType())
6877 Ty = S.Context.getLValueReferenceType(Ty,
6878 (*ResultType)->getAs<LValueReferenceType>()->isSpelledAsLValue());
6882 InitListExpr *StructuredInitList =
6883 PerformInitList.getFullyStructuredList();
6885 CurInit = shouldBindAsTemporary(InitEntity)
6886 ? S.MaybeBindToTemporary(StructuredInitList)
6887 : StructuredInitList;
6891 case SK_ConstructorInitializationFromList: {
6892 if (checkAbstractType(Step->Type))
6895 // When an initializer list is passed for a parameter of type "reference
6896 // to object", we don't get an EK_Temporary entity, but instead an
6897 // EK_Parameter entity with reference type.
6898 // FIXME: This is a hack. What we really should do is create a user
6899 // conversion step for this case, but this makes it considerably more
6900 // complicated. For now, this will do.
6901 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
6902 Entity.getType().getNonReferenceType());
6903 bool UseTemporary = Entity.getType()->isReferenceType();
6904 assert(Args.size() == 1 && "expected a single argument for list init");
6905 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
6906 S.Diag(InitList->getExprLoc(), diag::warn_cxx98_compat_ctor_list_init)
6907 << InitList->getSourceRange();
6908 MultiExprArg Arg(InitList->getInits(), InitList->getNumInits());
6909 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity :
6912 ConstructorInitRequiresZeroInit,
6913 /*IsListInitialization*/true,
6914 /*IsStdInitListInit*/false,
6915 InitList->getLBraceLoc(),
6916 InitList->getRBraceLoc());
6920 case SK_UnwrapInitList:
6921 CurInit = cast<InitListExpr>(CurInit.get())->getInit(0);
6924 case SK_RewrapInitList: {
6925 Expr *E = CurInit.get();
6926 InitListExpr *Syntactic = Step->WrappingSyntacticList;
6927 InitListExpr *ILE = new (S.Context) InitListExpr(S.Context,
6928 Syntactic->getLBraceLoc(), E, Syntactic->getRBraceLoc());
6929 ILE->setSyntacticForm(Syntactic);
6930 ILE->setType(E->getType());
6931 ILE->setValueKind(E->getValueKind());
6936 case SK_ConstructorInitialization:
6937 case SK_StdInitializerListConstructorCall: {
6938 if (checkAbstractType(Step->Type))
6941 // When an initializer list is passed for a parameter of type "reference
6942 // to object", we don't get an EK_Temporary entity, but instead an
6943 // EK_Parameter entity with reference type.
6944 // FIXME: This is a hack. What we really should do is create a user
6945 // conversion step for this case, but this makes it considerably more
6946 // complicated. For now, this will do.
6947 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(
6948 Entity.getType().getNonReferenceType());
6949 bool UseTemporary = Entity.getType()->isReferenceType();
6950 bool IsStdInitListInit =
6951 Step->Kind == SK_StdInitializerListConstructorCall;
6952 Expr *Source = CurInit.get();
6953 CurInit = PerformConstructorInitialization(
6954 S, UseTemporary ? TempEntity : Entity, Kind,
6955 Source ? MultiExprArg(Source) : Args, *Step,
6956 ConstructorInitRequiresZeroInit,
6957 /*IsListInitialization*/ IsStdInitListInit,
6958 /*IsStdInitListInitialization*/ IsStdInitListInit,
6959 /*LBraceLoc*/ SourceLocation(),
6960 /*RBraceLoc*/ SourceLocation());
6964 case SK_ZeroInitialization: {
6965 step_iterator NextStep = Step;
6967 if (NextStep != StepEnd &&
6968 (NextStep->Kind == SK_ConstructorInitialization ||
6969 NextStep->Kind == SK_ConstructorInitializationFromList)) {
6970 // The need for zero-initialization is recorded directly into
6971 // the call to the object's constructor within the next step.
6972 ConstructorInitRequiresZeroInit = true;
6973 } else if (Kind.getKind() == InitializationKind::IK_Value &&
6974 S.getLangOpts().CPlusPlus &&
6975 !Kind.isImplicitValueInit()) {
6976 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
6978 TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type,
6979 Kind.getRange().getBegin());
6981 CurInit = new (S.Context) CXXScalarValueInitExpr(
6982 TSInfo->getType().getNonLValueExprType(S.Context), TSInfo,
6983 Kind.getRange().getEnd());
6985 CurInit = new (S.Context) ImplicitValueInitExpr(Step->Type);
6990 case SK_CAssignment: {
6991 QualType SourceType = CurInit.get()->getType();
6992 // Save off the initial CurInit in case we need to emit a diagnostic
6993 ExprResult InitialCurInit = CurInit;
6994 ExprResult Result = CurInit;
6995 Sema::AssignConvertType ConvTy =
6996 S.CheckSingleAssignmentConstraints(Step->Type, Result, true,
6997 Entity.getKind() == InitializedEntity::EK_Parameter_CF_Audited);
6998 if (Result.isInvalid())
7002 // If this is a call, allow conversion to a transparent union.
7003 ExprResult CurInitExprRes = CurInit;
7004 if (ConvTy != Sema::Compatible &&
7005 Entity.isParameterKind() &&
7006 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes)
7007 == Sema::Compatible)
7008 ConvTy = Sema::Compatible;
7009 if (CurInitExprRes.isInvalid())
7011 CurInit = CurInitExprRes;
7014 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(),
7015 Step->Type, SourceType,
7016 InitialCurInit.get(),
7017 getAssignmentAction(Entity, true),
7019 PrintInitLocationNote(S, Entity);
7021 } else if (Complained)
7022 PrintInitLocationNote(S, Entity);
7026 case SK_StringInit: {
7027 QualType Ty = Step->Type;
7028 CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty,
7029 S.Context.getAsArrayType(Ty), S);
7033 case SK_ObjCObjectConversion:
7034 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
7035 CK_ObjCObjectLValueCast,
7036 CurInit.get()->getValueKind());
7039 case SK_ArrayLoopIndex: {
7040 Expr *Cur = CurInit.get();
7041 Expr *BaseExpr = new (S.Context)
7042 OpaqueValueExpr(Cur->getExprLoc(), Cur->getType(),
7043 Cur->getValueKind(), Cur->getObjectKind(), Cur);
7045 new (S.Context) ArrayInitIndexExpr(S.Context.getSizeType());
7046 CurInit = S.CreateBuiltinArraySubscriptExpr(
7047 BaseExpr, Kind.getLocation(), IndexExpr, Kind.getLocation());
7048 ArrayLoopCommonExprs.push_back(BaseExpr);
7052 case SK_ArrayLoopInit: {
7053 assert(!ArrayLoopCommonExprs.empty() &&
7054 "mismatched SK_ArrayLoopIndex and SK_ArrayLoopInit");
7055 Expr *Common = ArrayLoopCommonExprs.pop_back_val();
7056 CurInit = new (S.Context) ArrayInitLoopExpr(Step->Type, Common,
7061 case SK_GNUArrayInit:
7062 // Okay: we checked everything before creating this step. Note that
7063 // this is a GNU extension.
7064 S.Diag(Kind.getLocation(), diag::ext_array_init_copy)
7065 << Step->Type << CurInit.get()->getType()
7066 << CurInit.get()->getSourceRange();
7069 // If the destination type is an incomplete array type, update the
7070 // type accordingly.
7072 if (const IncompleteArrayType *IncompleteDest
7073 = S.Context.getAsIncompleteArrayType(Step->Type)) {
7074 if (const ConstantArrayType *ConstantSource
7075 = S.Context.getAsConstantArrayType(CurInit.get()->getType())) {
7076 *ResultType = S.Context.getConstantArrayType(
7077 IncompleteDest->getElementType(),
7078 ConstantSource->getSize(),
7079 ArrayType::Normal, 0);
7085 case SK_ParenthesizedArrayInit:
7086 // Okay: we checked everything before creating this step. Note that
7087 // this is a GNU extension.
7088 S.Diag(Kind.getLocation(), diag::ext_array_init_parens)
7089 << CurInit.get()->getSourceRange();
7092 case SK_PassByIndirectCopyRestore:
7093 case SK_PassByIndirectRestore:
7094 checkIndirectCopyRestoreSource(S, CurInit.get());
7095 CurInit = new (S.Context) ObjCIndirectCopyRestoreExpr(
7096 CurInit.get(), Step->Type,
7097 Step->Kind == SK_PassByIndirectCopyRestore);
7100 case SK_ProduceObjCObject:
7102 ImplicitCastExpr::Create(S.Context, Step->Type, CK_ARCProduceObject,
7103 CurInit.get(), nullptr, VK_RValue);
7106 case SK_StdInitializerList: {
7107 S.Diag(CurInit.get()->getExprLoc(),
7108 diag::warn_cxx98_compat_initializer_list_init)
7109 << CurInit.get()->getSourceRange();
7111 // Materialize the temporary into memory.
7112 MaterializeTemporaryExpr *MTE = S.CreateMaterializeTemporaryExpr(
7113 CurInit.get()->getType(), CurInit.get(),
7114 /*BoundToLvalueReference=*/false);
7116 // Maybe lifetime-extend the array temporary's subobjects to match the
7117 // entity's lifetime.
7118 if (const InitializedEntity *ExtendingEntity =
7119 getEntityForTemporaryLifetimeExtension(&Entity))
7120 if (performReferenceExtension(MTE, ExtendingEntity))
7121 warnOnLifetimeExtension(S, Entity, CurInit.get(),
7122 /*IsInitializerList=*/true,
7123 ExtendingEntity->getDecl());
7125 // Wrap it in a construction of a std::initializer_list<T>.
7126 CurInit = new (S.Context) CXXStdInitializerListExpr(Step->Type, MTE);
7128 // Bind the result, in case the library has given initializer_list a
7129 // non-trivial destructor.
7130 if (shouldBindAsTemporary(Entity))
7131 CurInit = S.MaybeBindToTemporary(CurInit.get());
7135 case SK_OCLSamplerInit: {
7136 // Sampler initialzation have 5 cases:
7137 // 1. function argument passing
7138 // 1a. argument is a file-scope variable
7139 // 1b. argument is a function-scope variable
7140 // 1c. argument is one of caller function's parameters
7141 // 2. variable initialization
7142 // 2a. initializing a file-scope variable
7143 // 2b. initializing a function-scope variable
7145 // For file-scope variables, since they cannot be initialized by function
7146 // call of __translate_sampler_initializer in LLVM IR, their references
7147 // need to be replaced by a cast from their literal initializers to
7148 // sampler type. Since sampler variables can only be used in function
7149 // calls as arguments, we only need to replace them when handling the
7150 // argument passing.
7151 assert(Step->Type->isSamplerT() &&
7152 "Sampler initialization on non-sampler type.");
7153 Expr *Init = CurInit.get();
7154 QualType SourceType = Init->getType();
7156 if (Entity.isParameterKind()) {
7157 if (!SourceType->isSamplerT()) {
7158 S.Diag(Kind.getLocation(), diag::err_sampler_argument_required)
7161 } else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Init)) {
7162 auto Var = cast<VarDecl>(DRE->getDecl());
7164 // No cast from integer to sampler is needed.
7165 if (!Var->hasGlobalStorage()) {
7166 CurInit = ImplicitCastExpr::Create(S.Context, Step->Type,
7167 CK_LValueToRValue, Init,
7168 /*BasePath=*/nullptr, VK_RValue);
7172 // For function call with a file-scope sampler variable as argument,
7173 // get the integer literal.
7174 // Do not diagnose if the file-scope variable does not have initializer
7175 // since this has already been diagnosed when parsing the variable
7177 if (!Var->getInit() || !isa<ImplicitCastExpr>(Var->getInit()))
7179 Init = cast<ImplicitCastExpr>(const_cast<Expr*>(
7180 Var->getInit()))->getSubExpr();
7181 SourceType = Init->getType();
7185 // Check initializer is 32 bit integer constant.
7186 // If the initializer is taken from global variable, do not diagnose since
7187 // this has already been done when parsing the variable declaration.
7188 if (!Init->isConstantInitializer(S.Context, false))
7191 if (!SourceType->isIntegerType() ||
7192 32 != S.Context.getIntWidth(SourceType)) {
7193 S.Diag(Kind.getLocation(), diag::err_sampler_initializer_not_integer)
7198 llvm::APSInt Result;
7199 Init->EvaluateAsInt(Result, S.Context);
7200 const uint64_t SamplerValue = Result.getLimitedValue();
7201 // 32-bit value of sampler's initializer is interpreted as
7202 // bit-field with the following structure:
7203 // |unspecified|Filter|Addressing Mode| Normalized Coords|
7204 // |31 6|5 4|3 1| 0|
7205 // This structure corresponds to enum values of sampler properties
7206 // defined in SPIR spec v1.2 and also opencl-c.h
7207 unsigned AddressingMode = (0x0E & SamplerValue) >> 1;
7208 unsigned FilterMode = (0x30 & SamplerValue) >> 4;
7209 if (FilterMode != 1 && FilterMode != 2)
7210 S.Diag(Kind.getLocation(),
7211 diag::warn_sampler_initializer_invalid_bits)
7213 if (AddressingMode > 4)
7214 S.Diag(Kind.getLocation(),
7215 diag::warn_sampler_initializer_invalid_bits)
7216 << "Addressing Mode";
7219 // Cases 1a, 2a and 2b
7220 // Insert cast from integer to sampler.
7221 CurInit = S.ImpCastExprToType(Init, S.Context.OCLSamplerTy,
7222 CK_IntToOCLSampler);
7225 case SK_OCLZeroEvent: {
7226 assert(Step->Type->isEventT() &&
7227 "Event initialization on non-event type.");
7229 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
7231 CurInit.get()->getValueKind());
7234 case SK_OCLZeroQueue: {
7235 assert(Step->Type->isQueueT() &&
7236 "Event initialization on non queue type.");
7238 CurInit = S.ImpCastExprToType(CurInit.get(), Step->Type,
7240 CurInit.get()->getValueKind());
7246 // Diagnose non-fatal problems with the completed initialization.
7247 if (Entity.getKind() == InitializedEntity::EK_Member &&
7248 cast<FieldDecl>(Entity.getDecl())->isBitField())
7249 S.CheckBitFieldInitialization(Kind.getLocation(),
7250 cast<FieldDecl>(Entity.getDecl()),
7253 // Check for std::move on construction.
7254 if (const Expr *E = CurInit.get()) {
7255 CheckMoveOnConstruction(S, E,
7256 Entity.getKind() == InitializedEntity::EK_Result);
7262 /// Somewhere within T there is an uninitialized reference subobject.
7263 /// Dig it out and diagnose it.
7264 static bool DiagnoseUninitializedReference(Sema &S, SourceLocation Loc,
7266 if (T->isReferenceType()) {
7267 S.Diag(Loc, diag::err_reference_without_init)
7268 << T.getNonReferenceType();
7272 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
7273 if (!RD || !RD->hasUninitializedReferenceMember())
7276 for (const auto *FI : RD->fields()) {
7277 if (FI->isUnnamedBitfield())
7280 if (DiagnoseUninitializedReference(S, FI->getLocation(), FI->getType())) {
7281 S.Diag(Loc, diag::note_value_initialization_here) << RD;
7286 for (const auto &BI : RD->bases()) {
7287 if (DiagnoseUninitializedReference(S, BI.getLocStart(), BI.getType())) {
7288 S.Diag(Loc, diag::note_value_initialization_here) << RD;
7297 //===----------------------------------------------------------------------===//
7298 // Diagnose initialization failures
7299 //===----------------------------------------------------------------------===//
7301 /// Emit notes associated with an initialization that failed due to a
7302 /// "simple" conversion failure.
7303 static void emitBadConversionNotes(Sema &S, const InitializedEntity &entity,
7305 QualType destType = entity.getType();
7306 if (destType.getNonReferenceType()->isObjCObjectPointerType() &&
7307 op->getType()->isObjCObjectPointerType()) {
7309 // Emit a possible note about the conversion failing because the
7310 // operand is a message send with a related result type.
7311 S.EmitRelatedResultTypeNote(op);
7313 // Emit a possible note about a return failing because we're
7314 // expecting a related result type.
7315 if (entity.getKind() == InitializedEntity::EK_Result)
7316 S.EmitRelatedResultTypeNoteForReturn(destType);
7320 static void diagnoseListInit(Sema &S, const InitializedEntity &Entity,
7321 InitListExpr *InitList) {
7322 QualType DestType = Entity.getType();
7325 if (S.getLangOpts().CPlusPlus11 && S.isStdInitializerList(DestType, &E)) {
7326 QualType ArrayType = S.Context.getConstantArrayType(
7328 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
7329 InitList->getNumInits()),
7330 clang::ArrayType::Normal, 0);
7331 InitializedEntity HiddenArray =
7332 InitializedEntity::InitializeTemporary(ArrayType);
7333 return diagnoseListInit(S, HiddenArray, InitList);
7336 if (DestType->isReferenceType()) {
7337 // A list-initialization failure for a reference means that we tried to
7338 // create a temporary of the inner type (per [dcl.init.list]p3.6) and the
7339 // inner initialization failed.
7340 QualType T = DestType->getAs<ReferenceType>()->getPointeeType();
7341 diagnoseListInit(S, InitializedEntity::InitializeTemporary(T), InitList);
7342 SourceLocation Loc = InitList->getLocStart();
7343 if (auto *D = Entity.getDecl())
7344 Loc = D->getLocation();
7345 S.Diag(Loc, diag::note_in_reference_temporary_list_initializer) << T;
7349 InitListChecker DiagnoseInitList(S, Entity, InitList, DestType,
7350 /*VerifyOnly=*/false,
7351 /*TreatUnavailableAsInvalid=*/false);
7352 assert(DiagnoseInitList.HadError() &&
7353 "Inconsistent init list check result.");
7356 bool InitializationSequence::Diagnose(Sema &S,
7357 const InitializedEntity &Entity,
7358 const InitializationKind &Kind,
7359 ArrayRef<Expr *> Args) {
7363 QualType DestType = Entity.getType();
7365 case FK_TooManyInitsForReference:
7366 // FIXME: Customize for the initialized entity?
7368 // Dig out the reference subobject which is uninitialized and diagnose it.
7369 // If this is value-initialization, this could be nested some way within
7371 assert(Kind.getKind() == InitializationKind::IK_Value ||
7372 DestType->isReferenceType());
7374 DiagnoseUninitializedReference(S, Kind.getLocation(), DestType);
7375 assert(Diagnosed && "couldn't find uninitialized reference to diagnose");
7377 } else // FIXME: diagnostic below could be better!
7378 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits)
7379 << SourceRange(Args.front()->getLocStart(), Args.back()->getLocEnd());
7382 case FK_ArrayNeedsInitList:
7383 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 0;
7385 case FK_ArrayNeedsInitListOrStringLiteral:
7386 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 1;
7388 case FK_ArrayNeedsInitListOrWideStringLiteral:
7389 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 2;
7391 case FK_NarrowStringIntoWideCharArray:
7392 S.Diag(Kind.getLocation(), diag::err_array_init_narrow_string_into_wchar);
7394 case FK_WideStringIntoCharArray:
7395 S.Diag(Kind.getLocation(), diag::err_array_init_wide_string_into_char);
7397 case FK_IncompatWideStringIntoWideChar:
7398 S.Diag(Kind.getLocation(),
7399 diag::err_array_init_incompat_wide_string_into_wchar);
7401 case FK_ArrayTypeMismatch:
7402 case FK_NonConstantArrayInit:
7403 S.Diag(Kind.getLocation(),
7404 (Failure == FK_ArrayTypeMismatch
7405 ? diag::err_array_init_different_type
7406 : diag::err_array_init_non_constant_array))
7407 << DestType.getNonReferenceType()
7408 << Args[0]->getType()
7409 << Args[0]->getSourceRange();
7412 case FK_VariableLengthArrayHasInitializer:
7413 S.Diag(Kind.getLocation(), diag::err_variable_object_no_init)
7414 << Args[0]->getSourceRange();
7417 case FK_AddressOfOverloadFailed: {
7418 DeclAccessPair Found;
7419 S.ResolveAddressOfOverloadedFunction(Args[0],
7420 DestType.getNonReferenceType(),
7426 case FK_AddressOfUnaddressableFunction: {
7427 auto *FD = cast<FunctionDecl>(cast<DeclRefExpr>(Args[0])->getDecl());
7428 S.checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
7429 Args[0]->getLocStart());
7433 case FK_ReferenceInitOverloadFailed:
7434 case FK_UserConversionOverloadFailed:
7435 switch (FailedOverloadResult) {
7437 if (Failure == FK_UserConversionOverloadFailed)
7438 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition)
7439 << Args[0]->getType() << DestType
7440 << Args[0]->getSourceRange();
7442 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous)
7443 << DestType << Args[0]->getType()
7444 << Args[0]->getSourceRange();
7446 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args);
7449 case OR_No_Viable_Function:
7450 if (!S.RequireCompleteType(Kind.getLocation(),
7451 DestType.getNonReferenceType(),
7452 diag::err_typecheck_nonviable_condition_incomplete,
7453 Args[0]->getType(), Args[0]->getSourceRange()))
7454 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition)
7455 << (Entity.getKind() == InitializedEntity::EK_Result)
7456 << Args[0]->getType() << Args[0]->getSourceRange()
7457 << DestType.getNonReferenceType();
7459 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args);
7463 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function)
7464 << Args[0]->getType() << DestType.getNonReferenceType()
7465 << Args[0]->getSourceRange();
7466 OverloadCandidateSet::iterator Best;
7467 OverloadingResult Ovl
7468 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best,
7470 if (Ovl == OR_Deleted) {
7471 S.NoteDeletedFunction(Best->Function);
7473 llvm_unreachable("Inconsistent overload resolution?");
7479 llvm_unreachable("Conversion did not fail!");
7483 case FK_NonConstLValueReferenceBindingToTemporary:
7484 if (isa<InitListExpr>(Args[0])) {
7485 S.Diag(Kind.getLocation(),
7486 diag::err_lvalue_reference_bind_to_initlist)
7487 << DestType.getNonReferenceType().isVolatileQualified()
7488 << DestType.getNonReferenceType()
7489 << Args[0]->getSourceRange();
7492 // Intentional fallthrough
7494 case FK_NonConstLValueReferenceBindingToUnrelated:
7495 S.Diag(Kind.getLocation(),
7496 Failure == FK_NonConstLValueReferenceBindingToTemporary
7497 ? diag::err_lvalue_reference_bind_to_temporary
7498 : diag::err_lvalue_reference_bind_to_unrelated)
7499 << DestType.getNonReferenceType().isVolatileQualified()
7500 << DestType.getNonReferenceType()
7501 << Args[0]->getType()
7502 << Args[0]->getSourceRange();
7505 case FK_NonConstLValueReferenceBindingToBitfield: {
7506 // We don't necessarily have an unambiguous source bit-field.
7507 FieldDecl *BitField = Args[0]->getSourceBitField();
7508 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield)
7509 << DestType.isVolatileQualified()
7510 << (BitField ? BitField->getDeclName() : DeclarationName())
7511 << (BitField != nullptr)
7512 << Args[0]->getSourceRange();
7514 S.Diag(BitField->getLocation(), diag::note_bitfield_decl);
7518 case FK_NonConstLValueReferenceBindingToVectorElement:
7519 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element)
7520 << DestType.isVolatileQualified()
7521 << Args[0]->getSourceRange();
7524 case FK_RValueReferenceBindingToLValue:
7525 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref)
7526 << DestType.getNonReferenceType() << Args[0]->getType()
7527 << Args[0]->getSourceRange();
7530 case FK_ReferenceInitDropsQualifiers: {
7531 QualType SourceType = Args[0]->getType();
7532 QualType NonRefType = DestType.getNonReferenceType();
7533 Qualifiers DroppedQualifiers =
7534 SourceType.getQualifiers() - NonRefType.getQualifiers();
7536 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals)
7539 << DroppedQualifiers.getCVRQualifiers()
7540 << Args[0]->getSourceRange();
7544 case FK_ReferenceInitFailed:
7545 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed)
7546 << DestType.getNonReferenceType()
7547 << Args[0]->isLValue()
7548 << Args[0]->getType()
7549 << Args[0]->getSourceRange();
7550 emitBadConversionNotes(S, Entity, Args[0]);
7553 case FK_ConversionFailed: {
7554 QualType FromType = Args[0]->getType();
7555 PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed)
7556 << (int)Entity.getKind()
7558 << Args[0]->isLValue()
7560 << Args[0]->getSourceRange();
7561 S.HandleFunctionTypeMismatch(PDiag, FromType, DestType);
7562 S.Diag(Kind.getLocation(), PDiag);
7563 emitBadConversionNotes(S, Entity, Args[0]);
7567 case FK_ConversionFromPropertyFailed:
7568 // No-op. This error has already been reported.
7571 case FK_TooManyInitsForScalar: {
7574 auto *InitList = dyn_cast<InitListExpr>(Args[0]);
7575 if (InitList && InitList->getNumInits() >= 1) {
7576 R = SourceRange(InitList->getInit(0)->getLocEnd(), InitList->getLocEnd());
7578 assert(Args.size() > 1 && "Expected multiple initializers!");
7579 R = SourceRange(Args.front()->getLocEnd(), Args.back()->getLocEnd());
7582 R.setBegin(S.getLocForEndOfToken(R.getBegin()));
7583 if (Kind.isCStyleOrFunctionalCast())
7584 S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg)
7587 S.Diag(Kind.getLocation(), diag::err_excess_initializers)
7588 << /*scalar=*/2 << R;
7592 case FK_ReferenceBindingToInitList:
7593 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list)
7594 << DestType.getNonReferenceType() << Args[0]->getSourceRange();
7597 case FK_InitListBadDestinationType:
7598 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type)
7599 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange();
7602 case FK_ListConstructorOverloadFailed:
7603 case FK_ConstructorOverloadFailed: {
7604 SourceRange ArgsRange;
7606 ArgsRange = SourceRange(Args.front()->getLocStart(),
7607 Args.back()->getLocEnd());
7609 if (Failure == FK_ListConstructorOverloadFailed) {
7610 assert(Args.size() == 1 &&
7611 "List construction from other than 1 argument.");
7612 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
7613 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
7616 // FIXME: Using "DestType" for the entity we're printing is probably
7618 switch (FailedOverloadResult) {
7620 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init)
7621 << DestType << ArgsRange;
7622 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args);
7625 case OR_No_Viable_Function:
7626 if (Kind.getKind() == InitializationKind::IK_Default &&
7627 (Entity.getKind() == InitializedEntity::EK_Base ||
7628 Entity.getKind() == InitializedEntity::EK_Member) &&
7629 isa<CXXConstructorDecl>(S.CurContext)) {
7630 // This is implicit default initialization of a member or
7631 // base within a constructor. If no viable function was
7632 // found, notify the user that they need to explicitly
7633 // initialize this base/member.
7634 CXXConstructorDecl *Constructor
7635 = cast<CXXConstructorDecl>(S.CurContext);
7636 const CXXRecordDecl *InheritedFrom = nullptr;
7637 if (auto Inherited = Constructor->getInheritedConstructor())
7638 InheritedFrom = Inherited.getShadowDecl()->getNominatedBaseClass();
7639 if (Entity.getKind() == InitializedEntity::EK_Base) {
7640 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
7641 << (InheritedFrom ? 2 : Constructor->isImplicit() ? 1 : 0)
7642 << S.Context.getTypeDeclType(Constructor->getParent())
7647 RecordDecl *BaseDecl
7648 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>()
7650 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl)
7651 << S.Context.getTagDeclType(BaseDecl);
7653 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor)
7654 << (InheritedFrom ? 2 : Constructor->isImplicit() ? 1 : 0)
7655 << S.Context.getTypeDeclType(Constructor->getParent())
7659 S.Diag(Entity.getDecl()->getLocation(),
7660 diag::note_member_declared_at);
7662 if (const RecordType *Record
7663 = Entity.getType()->getAs<RecordType>())
7664 S.Diag(Record->getDecl()->getLocation(),
7665 diag::note_previous_decl)
7666 << S.Context.getTagDeclType(Record->getDecl());
7671 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init)
7672 << DestType << ArgsRange;
7673 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args);
7677 OverloadCandidateSet::iterator Best;
7678 OverloadingResult Ovl
7679 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
7680 if (Ovl != OR_Deleted) {
7681 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
7682 << true << DestType << ArgsRange;
7683 llvm_unreachable("Inconsistent overload resolution?");
7687 // If this is a defaulted or implicitly-declared function, then
7688 // it was implicitly deleted. Make it clear that the deletion was
7690 if (S.isImplicitlyDeleted(Best->Function))
7691 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init)
7692 << S.getSpecialMember(cast<CXXMethodDecl>(Best->Function))
7693 << DestType << ArgsRange;
7695 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init)
7696 << true << DestType << ArgsRange;
7698 S.NoteDeletedFunction(Best->Function);
7703 llvm_unreachable("Conversion did not fail!");
7708 case FK_DefaultInitOfConst:
7709 if (Entity.getKind() == InitializedEntity::EK_Member &&
7710 isa<CXXConstructorDecl>(S.CurContext)) {
7711 // This is implicit default-initialization of a const member in
7712 // a constructor. Complain that it needs to be explicitly
7714 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext);
7715 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor)
7716 << (Constructor->getInheritedConstructor() ? 2 :
7717 Constructor->isImplicit() ? 1 : 0)
7718 << S.Context.getTypeDeclType(Constructor->getParent())
7720 << Entity.getName();
7721 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl)
7722 << Entity.getName();
7724 S.Diag(Kind.getLocation(), diag::err_default_init_const)
7725 << DestType << (bool)DestType->getAs<RecordType>();
7730 S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType,
7731 diag::err_init_incomplete_type);
7734 case FK_ListInitializationFailed: {
7735 // Run the init list checker again to emit diagnostics.
7736 InitListExpr *InitList = cast<InitListExpr>(Args[0]);
7737 diagnoseListInit(S, Entity, InitList);
7741 case FK_PlaceholderType: {
7742 // FIXME: Already diagnosed!
7746 case FK_ExplicitConstructor: {
7747 S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor)
7748 << Args[0]->getSourceRange();
7749 OverloadCandidateSet::iterator Best;
7750 OverloadingResult Ovl
7751 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best);
7753 assert(Ovl == OR_Success && "Inconsistent overload resolution");
7754 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
7755 S.Diag(CtorDecl->getLocation(), diag::note_constructor_declared_here);
7760 PrintInitLocationNote(S, Entity);
7764 void InitializationSequence::dump(raw_ostream &OS) const {
7765 switch (SequenceKind) {
7766 case FailedSequence: {
7767 OS << "Failed sequence: ";
7769 case FK_TooManyInitsForReference:
7770 OS << "too many initializers for reference";
7773 case FK_ArrayNeedsInitList:
7774 OS << "array requires initializer list";
7777 case FK_AddressOfUnaddressableFunction:
7778 OS << "address of unaddressable function was taken";
7781 case FK_ArrayNeedsInitListOrStringLiteral:
7782 OS << "array requires initializer list or string literal";
7785 case FK_ArrayNeedsInitListOrWideStringLiteral:
7786 OS << "array requires initializer list or wide string literal";
7789 case FK_NarrowStringIntoWideCharArray:
7790 OS << "narrow string into wide char array";
7793 case FK_WideStringIntoCharArray:
7794 OS << "wide string into char array";
7797 case FK_IncompatWideStringIntoWideChar:
7798 OS << "incompatible wide string into wide char array";
7801 case FK_ArrayTypeMismatch:
7802 OS << "array type mismatch";
7805 case FK_NonConstantArrayInit:
7806 OS << "non-constant array initializer";
7809 case FK_AddressOfOverloadFailed:
7810 OS << "address of overloaded function failed";
7813 case FK_ReferenceInitOverloadFailed:
7814 OS << "overload resolution for reference initialization failed";
7817 case FK_NonConstLValueReferenceBindingToTemporary:
7818 OS << "non-const lvalue reference bound to temporary";
7821 case FK_NonConstLValueReferenceBindingToBitfield:
7822 OS << "non-const lvalue reference bound to bit-field";
7825 case FK_NonConstLValueReferenceBindingToVectorElement:
7826 OS << "non-const lvalue reference bound to vector element";
7829 case FK_NonConstLValueReferenceBindingToUnrelated:
7830 OS << "non-const lvalue reference bound to unrelated type";
7833 case FK_RValueReferenceBindingToLValue:
7834 OS << "rvalue reference bound to an lvalue";
7837 case FK_ReferenceInitDropsQualifiers:
7838 OS << "reference initialization drops qualifiers";
7841 case FK_ReferenceInitFailed:
7842 OS << "reference initialization failed";
7845 case FK_ConversionFailed:
7846 OS << "conversion failed";
7849 case FK_ConversionFromPropertyFailed:
7850 OS << "conversion from property failed";
7853 case FK_TooManyInitsForScalar:
7854 OS << "too many initializers for scalar";
7857 case FK_ReferenceBindingToInitList:
7858 OS << "referencing binding to initializer list";
7861 case FK_InitListBadDestinationType:
7862 OS << "initializer list for non-aggregate, non-scalar type";
7865 case FK_UserConversionOverloadFailed:
7866 OS << "overloading failed for user-defined conversion";
7869 case FK_ConstructorOverloadFailed:
7870 OS << "constructor overloading failed";
7873 case FK_DefaultInitOfConst:
7874 OS << "default initialization of a const variable";
7878 OS << "initialization of incomplete type";
7881 case FK_ListInitializationFailed:
7882 OS << "list initialization checker failure";
7885 case FK_VariableLengthArrayHasInitializer:
7886 OS << "variable length array has an initializer";
7889 case FK_PlaceholderType:
7890 OS << "initializer expression isn't contextually valid";
7893 case FK_ListConstructorOverloadFailed:
7894 OS << "list constructor overloading failed";
7897 case FK_ExplicitConstructor:
7898 OS << "list copy initialization chose explicit constructor";
7905 case DependentSequence:
7906 OS << "Dependent sequence\n";
7909 case NormalSequence:
7910 OS << "Normal sequence: ";
7914 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) {
7915 if (S != step_begin()) {
7920 case SK_ResolveAddressOfOverloadedFunction:
7921 OS << "resolve address of overloaded function";
7924 case SK_CastDerivedToBaseRValue:
7925 OS << "derived-to-base (rvalue)";
7928 case SK_CastDerivedToBaseXValue:
7929 OS << "derived-to-base (xvalue)";
7932 case SK_CastDerivedToBaseLValue:
7933 OS << "derived-to-base (lvalue)";
7936 case SK_BindReference:
7937 OS << "bind reference to lvalue";
7940 case SK_BindReferenceToTemporary:
7941 OS << "bind reference to a temporary";
7945 OS << "final copy in class direct-initialization";
7948 case SK_ExtraneousCopyToTemporary:
7949 OS << "extraneous C++03 copy to temporary";
7952 case SK_UserConversion:
7953 OS << "user-defined conversion via " << *S->Function.Function;
7956 case SK_QualificationConversionRValue:
7957 OS << "qualification conversion (rvalue)";
7960 case SK_QualificationConversionXValue:
7961 OS << "qualification conversion (xvalue)";
7964 case SK_QualificationConversionLValue:
7965 OS << "qualification conversion (lvalue)";
7968 case SK_AtomicConversion:
7969 OS << "non-atomic-to-atomic conversion";
7972 case SK_LValueToRValue:
7973 OS << "load (lvalue to rvalue)";
7976 case SK_ConversionSequence:
7977 OS << "implicit conversion sequence (";
7978 S->ICS->dump(); // FIXME: use OS
7982 case SK_ConversionSequenceNoNarrowing:
7983 OS << "implicit conversion sequence with narrowing prohibited (";
7984 S->ICS->dump(); // FIXME: use OS
7988 case SK_ListInitialization:
7989 OS << "list aggregate initialization";
7992 case SK_UnwrapInitList:
7993 OS << "unwrap reference initializer list";
7996 case SK_RewrapInitList:
7997 OS << "rewrap reference initializer list";
8000 case SK_ConstructorInitialization:
8001 OS << "constructor initialization";
8004 case SK_ConstructorInitializationFromList:
8005 OS << "list initialization via constructor";
8008 case SK_ZeroInitialization:
8009 OS << "zero initialization";
8012 case SK_CAssignment:
8013 OS << "C assignment";
8017 OS << "string initialization";
8020 case SK_ObjCObjectConversion:
8021 OS << "Objective-C object conversion";
8024 case SK_ArrayLoopIndex:
8025 OS << "indexing for array initialization loop";
8028 case SK_ArrayLoopInit:
8029 OS << "array initialization loop";
8033 OS << "array initialization";
8036 case SK_GNUArrayInit:
8037 OS << "array initialization (GNU extension)";
8040 case SK_ParenthesizedArrayInit:
8041 OS << "parenthesized array initialization";
8044 case SK_PassByIndirectCopyRestore:
8045 OS << "pass by indirect copy and restore";
8048 case SK_PassByIndirectRestore:
8049 OS << "pass by indirect restore";
8052 case SK_ProduceObjCObject:
8053 OS << "Objective-C object retension";
8056 case SK_StdInitializerList:
8057 OS << "std::initializer_list from initializer list";
8060 case SK_StdInitializerListConstructorCall:
8061 OS << "list initialization from std::initializer_list";
8064 case SK_OCLSamplerInit:
8065 OS << "OpenCL sampler_t from integer constant";
8068 case SK_OCLZeroEvent:
8069 OS << "OpenCL event_t from zero";
8072 case SK_OCLZeroQueue:
8073 OS << "OpenCL queue_t from zero";
8077 OS << " [" << S->Type.getAsString() << ']';
8083 void InitializationSequence::dump() const {
8087 static void DiagnoseNarrowingInInitList(Sema &S,
8088 const ImplicitConversionSequence &ICS,
8089 QualType PreNarrowingType,
8090 QualType EntityType,
8091 const Expr *PostInit) {
8092 const StandardConversionSequence *SCS = nullptr;
8093 switch (ICS.getKind()) {
8094 case ImplicitConversionSequence::StandardConversion:
8095 SCS = &ICS.Standard;
8097 case ImplicitConversionSequence::UserDefinedConversion:
8098 SCS = &ICS.UserDefined.After;
8100 case ImplicitConversionSequence::AmbiguousConversion:
8101 case ImplicitConversionSequence::EllipsisConversion:
8102 case ImplicitConversionSequence::BadConversion:
8106 // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion.
8107 APValue ConstantValue;
8108 QualType ConstantType;
8109 switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue,
8111 case NK_Not_Narrowing:
8112 case NK_Dependent_Narrowing:
8113 // No narrowing occurred.
8116 case NK_Type_Narrowing:
8117 // This was a floating-to-integer conversion, which is always considered a
8118 // narrowing conversion even if the value is a constant and can be
8119 // represented exactly as an integer.
8120 S.Diag(PostInit->getLocStart(),
8121 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
8122 ? diag::warn_init_list_type_narrowing
8123 : diag::ext_init_list_type_narrowing)
8124 << PostInit->getSourceRange()
8125 << PreNarrowingType.getLocalUnqualifiedType()
8126 << EntityType.getLocalUnqualifiedType();
8129 case NK_Constant_Narrowing:
8130 // A constant value was narrowed.
8131 S.Diag(PostInit->getLocStart(),
8132 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
8133 ? diag::warn_init_list_constant_narrowing
8134 : diag::ext_init_list_constant_narrowing)
8135 << PostInit->getSourceRange()
8136 << ConstantValue.getAsString(S.getASTContext(), ConstantType)
8137 << EntityType.getLocalUnqualifiedType();
8140 case NK_Variable_Narrowing:
8141 // A variable's value may have been narrowed.
8142 S.Diag(PostInit->getLocStart(),
8143 (S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11)
8144 ? diag::warn_init_list_variable_narrowing
8145 : diag::ext_init_list_variable_narrowing)
8146 << PostInit->getSourceRange()
8147 << PreNarrowingType.getLocalUnqualifiedType()
8148 << EntityType.getLocalUnqualifiedType();
8152 SmallString<128> StaticCast;
8153 llvm::raw_svector_ostream OS(StaticCast);
8154 OS << "static_cast<";
8155 if (const TypedefType *TT = EntityType->getAs<TypedefType>()) {
8156 // It's important to use the typedef's name if there is one so that the
8157 // fixit doesn't break code using types like int64_t.
8159 // FIXME: This will break if the typedef requires qualification. But
8160 // getQualifiedNameAsString() includes non-machine-parsable components.
8161 OS << *TT->getDecl();
8162 } else if (const BuiltinType *BT = EntityType->getAs<BuiltinType>())
8163 OS << BT->getName(S.getLangOpts());
8165 // Oops, we didn't find the actual type of the variable. Don't emit a fixit
8166 // with a broken cast.
8170 S.Diag(PostInit->getLocStart(), diag::note_init_list_narrowing_silence)
8171 << PostInit->getSourceRange()
8172 << FixItHint::CreateInsertion(PostInit->getLocStart(), OS.str())
8173 << FixItHint::CreateInsertion(
8174 S.getLocForEndOfToken(PostInit->getLocEnd()), ")");
8177 //===----------------------------------------------------------------------===//
8178 // Initialization helper functions
8179 //===----------------------------------------------------------------------===//
8181 Sema::CanPerformCopyInitialization(const InitializedEntity &Entity,
8183 if (Init.isInvalid())
8186 Expr *InitE = Init.get();
8187 assert(InitE && "No initialization expression");
8189 InitializationKind Kind
8190 = InitializationKind::CreateCopy(InitE->getLocStart(), SourceLocation());
8191 InitializationSequence Seq(*this, Entity, Kind, InitE);
8192 return !Seq.Failed();
8196 Sema::PerformCopyInitialization(const InitializedEntity &Entity,
8197 SourceLocation EqualLoc,
8199 bool TopLevelOfInitList,
8200 bool AllowExplicit) {
8201 if (Init.isInvalid())
8204 Expr *InitE = Init.get();
8205 assert(InitE && "No initialization expression?");
8207 if (EqualLoc.isInvalid())
8208 EqualLoc = InitE->getLocStart();
8210 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(),
8213 InitializationSequence Seq(*this, Entity, Kind, InitE, TopLevelOfInitList);
8215 ExprResult Result = Seq.Perform(*this, Entity, Kind, InitE);